After Childbirth Ebook

Getting Back Into Shape After The Pregnancy

Getting Back Into Shape After The Pregnancy

Once your pregnancy is over and done with, your baby is happily in your arms, and youre headed back home from the hospital, youll begin to realize that things have only just begun. Over the next few days, weeks, and months, youre going to increasingly notice that your entire life has changed in more ways than you could ever imagine.

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Pregnancy Without Pounds

This proven program will get you through your pregnancy in better shape than most other women in as little as 27 minutes a day and with minimal effort. It contains all the information that I believe will Help you to look and feel like I did barefoot and beautiful! Inside you will learn Exactly how to avoid unwanted pounds, overcome your food cravings, care for your skin, dress to kill and look like one Hot Mama. Ive also put together Fifty simple, yet extremely effective pregnancy-friendly exercises and stretches to keep you and your body looking and feeling Great (includes 3 different fitness programs depending on Your fitness level)!

Pregnancy Without Pounds Summary


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Contents: Ebook
Author: Michelle Moss
Price: $39.95

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Highly Recommended

I've really worked on the chapters in this ebook and can only say that if you put in the time you will never revert back to your old methods.

All the modules inside this ebook are very detailed and explanatory, there is nothing as comprehensive as this guide.

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Intrarenal Angiotensin Ii Receptors

The AT2 receptor is highly expressed in human and rodent kidney mesenchyme during fetal life and decreases dramatically after birth (115). AT2 receptors have been localized to the glomerular epithelial cells, proximal tubules, collecting ducts, and parts of the renal vasculature of the adult rat (106,112). Although the role of AT2 receptors in regulating renal function remains uncertain, it has been suggested that AT2 activation counteracts AT1 receptor effects by stimulating the formation of bradykinin and nitric oxide leading to increases in interstitial fluid concentration of cyclic guanosine monophosphate (cGMP) (116-118). AT2 receptor activation appears to influence proximal tubule sodium reabsorption either by a cell membrane receptor-mediated mechanism or via an interstitial nitric oxide-cGMP pathway (119). Ang II infusion into AT2 knockout mice leads to exaggerated hypertension and reductions in renal function, probably because of the decreased renal interstitial fluid levels...

Induction of Immune Tolerance in Neonatal Mice

Inject the neonates daily on d 1-5 after birth with 0.05 mL 0.5 mg mL of crossreacting antigen into the neck scruff. (The neonatal immune systems are maturing at this time and because the cross-reacting antigen is present they will adopt these proteins as self and lose the ability to mount an immune response to them.)

Economic Growth and Modernization

The average weight gain after pregnancy is less than 1 kg although the range is wide. In many developing countries, consecutive pregnancies with short spacing often result in weight loss rather than weight gain. Menopausal women are particularly prone to rapid weight gain. This is primarily due to reductions in activity although loss of the menstrual cycle also affects food intake and reduces metabolic rate slightly.

Metabolic myopathies

The infantile form (Pompe's disease) presents a few months after birth with diffuse muscle weakness, severe hypotonia, and cardiomyopathy with congestive heart failure. Death caused by cardiorespiratory failure occurs within 2 years. The adult or late-onset form is caused by a partial deficiency of acid maltase activity. The late-onset form presents in childhood or adult life with gradually progressive limb-girdle weakness. The pelvic girdle muscles are more involved than the shoulder muscles. Clinical heart or liver involvement has not been seen. Respiratory muscle involvement, seen in 25 to 50 of cases, leads to chronic respiratory insufficiency. The late-onset form may be mistaken for polymyositis, limb-girdle dystrophy, or spinal muscular atrophy.

Networks are Formed by Genotype and Environment

Different groups of neurons are incorporated into different networks of functional activities in the brain known as neuronal systems. If parts of these systems or their connections are lost (as in the case of degeneration or trauma) or are not properly working (as the result of toxins or the transient overexposure to neuro-active compounds), the functional capacity of the system is affected. The neuronal cell acquisition of the human nervous system takes place both before and after birth, and continues in young children up to approximately three years of age. Neuronal networks are formed throughout this period too but continue to be formed up to approximately 18 years of age, i.e. until after puberty, when the nervous system is said to be fully matured. Brain development is an orchestrated process whereby the birth of neurons during fetal life is genetically defined, but the differentiation, maturation and organisation of neurons depends on the appearance of other groups of neurons...

Prepubertal Proliferation of Sertoli Cells

In humans and macaques, the ontogeny of Sertoli cell proliferation is different from that in rodents (54-60). Cortes et al. (56), using autopsy material from boys and men who had died in traumatic accidents, described two phases of Sertoli cell proliferation, one immediately after birth and one later at puberty. Each of these periods in higher primates is associated with elevated levels of gonadotropins (61). In the rhesus monkey, the number of Sertoli cells per testis was increased fivefold from infancy to the juvenile phase of development, with a further sixfold increase from the juvenile to the adult phase. These increments in Sertoli cell number occurred during infancy and the puber-tal period concomitant with the elevated gonadotropin levels that are characteristic of these developmental phases (57). Moreover, GnRH administration to juvenile rhesus macaques that are naturally hypogonadotropic resulted in precocious LH and FSH secretion that, in turn, stimulated a premature...

Compositional Changes in the Developing Brain

At birth, cerebral hemispheric white matter contains very little myelin and the white matter composition of neonates is very different from the composition of mature myelinated white matter. There is an important overall decrease in water content of the brain after birth and the change in water content is larger for white matter than for gray matter. The water content of neonatal gray matter is about 89 and of neonatal unmyelinated white matter about 87 , whereas the water content of adult gray matter is estimated to be 82 and of adult myelinated white matter 72 . The lipid composition of cerebral white mat

Age Structures and Sex Ratios

Since most animals are unisexual, an important demographic characteristic of a population is its sex ratio, defined as the ratio of males to females. While the ratio for birds and mammals tends to be 1 1 at conception (the fertilization of an egg), it tends to be weighted toward males at birth, because female embryos are slightly less viable. After birth, the sex ratio for mammals tends to favor females, because young males suffer higher mortality. The posthatching ratio in birds tends to remain skewed toward males, because females devote considerable energy to producing young and suffer higher mortality. As a result, male birds must compete with one another for the opportunity to mate with the scarcer females.

Abnormalities of sensation

Carpal tunnel syndrome is produced by compression of the median nerve at the wrist. As the nerve passes through the unyielding carpal tunnel, it is at risk for compression by the transverse carpal ligament. In most patients, no specific etiology can be determined, but thickening and proliferation of the peritendinous synovium is seen. This condition is very common in RA, in diabetes, during or after pregnancy, and after wrist fracture. It is also seen in postmenopausal women and in patients with the myxedema of thyroid disease.

Benign Familial Neonatal Epilepsy

When my niece was born, she stopped breathing during her first day of life and suffered from recurrent brief seizures until she was 3 months old, after which they ceased. This pattern is typical of benign familial neonatal convulsions (BFNC), a disorder associated with neonatal convulsions that usually present within the first 3 days after birth and show spontaneous remission by the third month of life. Paroxysmal fetal convulsions during the last two months of pregnancy have also been reported. Neurocognitive development is usually normal, but there is an increased risk of subsequent epilepsy in 10-15 of individuals in later life. In most families the gene responsible for BFNC maps to chromosome 20q13.3 and is inherited in an autosomal dominant manner. A second locus for BFNC has also been identified, which lies on chromosome 8q24.

Cardiac Growth And Hypertrophy

Physiologic hypertrophy includes cardiogenesis during embryonic development, postnatal cardiac growth, a modest additional increase in heart size that evolves during senescence, and the increase in heart size that occurs in response to athletic conditioning. The earliest stage of cardiac growth in utero depends on a genetically determined developmental program, since it can occur in the absence of contractile activity. Subsequently, mechanical forces become increasingly important in the development of the normal cardiac phenotype. Throughout the embryonic period and for a few weeks after birth, cardiac growth occurs as a consequence of hyperplasia and hypertrophy of myocytes (see Chap. 9). Classically, adult myocytes have been described as terminally differentiated-that is, incapable of reentering the cell cycle. This issue is currently undergoing reexamination. It is critical to make a distinction between DNA synthesis and cell division. In the adult cardiomyocyte, DNA synthesis may...

Screening for abnormal phenotypes can make use of protein expression

After birth, however, the situation changes. The baby begins to consume protein-rich food (milk) and to break down some of its own proteins. Phenylalanine enters the baby's blood, and without the mother's phenylalanine hydroxylase to break it down, accumulates there. After a few days, the phenylalanine level in the baby's blood may be ten times higher than normal. Within days, the developing brain is damaged, and untreated children with PKU become severely mentally retarded. A heel-stick blood sample is taken a few days after birth.

Fat Intake And Adiposity In Children

One mediating factor (and possibly a mechanism) in the development of adult obesity from childhood involves the so-called 'adiposity rebound' (AR). This is the name given to the second augmentation of BMI after birth, and there is an inverse relationship between adult BMI and the age of AR. In a longitudinal study of Czech children, followed from 1 month of age to adulthood, the heaviest adults had an AR around 5 years and the leanest at 7.6

The Transition From Fetal to Neonatal Life Involves a Complex Sequence of Cardiovascular Events

During all the processes just described, the open foramen ovale must be sealed to prevent blood flow from the left to right atrium. Left atrial pressure increases from the returning blood from the lungs and exceeds right atrial pressure. This pressure difference passively pushes the tissue flap on the left side of the foramen ovale against the open atrial septum. In time, the tissues of the atrial septum fuse,- however, an anatomic passage that is probably only passively sealed can be documented in some adults. The ductus venosus in the liver is open for several days after birth but gradually closes and is obliterated within 2 to 3 months.

Chronic Granulomatous Disease

This is a very rare disease affecting mostly males, although it is not strictly X-linked. Several genes are probably involved. It shows up soon after birth, when bacterial and fungus infections become increasingly common in these infants. Fevers, rashes, swollen lymph nodes, and even boils (bacterial abscesses) are common. The problem in this case is not in the production of antibodies, but in the ability of phagocytes to destroy antibody-tagged microbes after they have been engulfed. The failure to resolve the infection, however, causes continuous influx of macrophages to the infection site, and these soon form large, palpable masses called granulomas, which can begin to interfere with the function of nearby normal tissues. These children are also commonly anemic. Draining of abscesses, where necessary, and intensive treatment with antibiotics are required to resolve many infections that in most children would be relatively trivial. In some infants, a bone marrow transplant can...

Coming Truly Naked Into The World Scid

Keeping these children alive is a daunting task, for which only the best hospitals are equipped. Even then most do not survive. Too often they are brought to the hospital with advanced micro-bial infections that simply cannot be controlled in time to prevent death. Once SCID became generally recognized and management of it made a standard part of a pediatrician's training, it was realized that many of these infants developed fatal complications from immunizations with highly (but often not completely) attenuated vaccines shortly after birth. How many of these infants died from vaccinations prior to this realization is unknown. Fortunately, SCID is a rather rare condition. Only about 40 SCID kids are born each year in the United States. The best known case of a SCID kid was a young boy named David, who became known to millions of Americans and others around the world as the Bubble Boy. David was born in 1971. Because a previous male child born to his parents had proved to have SCID and...

Congenital thymic aplasia Di George syndrome

In contrast to many other immunodeficiency diseases, which become apparent after the loss of maternal antibodies, Di George syndrome is associated with symptoms that appear immediately after birth owing to defective T cell function. Affected babies have a range of abnormal clinical features (Table 5.14) and at birth will be lymphopenic (i.e. will have severely decreased numbers of lymphocytes) with very few circulating T cells. In addition, lymphocytes fail to proliferate in response to stimulation with mitogens (e.g. phytohaemagglutinin - PHA) or allogeneic cells. Thus,

Severe combined immunodeficiency disease SCID

Due to the T cell abnormality, shortly after birth affected babies may develop disseminated yeast infections (usually caused by Monilia spp.), severe pneumonia (caused by Pneumocystis carinii) and recurrent infections caused by other opportunistic pathogens (organisms which, in healthy individuals, are normally prevented from causing disease by the immune system). Since these infections usually affect the skin and the pulmonary and gastrointestinal tracts, their prevalence in patients with SCID suggests that the defect also affects the immune mechanisms normally involved in surface and mucosal immunity. Since both the cell-mediated and humoral systems are affected, patients may die as a result of infection with common viruses such as varicella, herpes and cytomegalovirus. In addition, affected children often have chronic diarrhoea and malabsorption of nutrients from the gut, resulting in a failure to thrive.

Pattern And Variability Of Pregnancyrelated Weight Gains

Overall, robust longitudinal studies suggest that women experience average long-term weight gains of up to 3 kg in association with pregnancy. However, the pattern of weight change after pregnancy is not well documented and varies considerably between women. For the majority of women, pregnancy does not trigger obesity and most women can expect to regain their pre-pregnant weight within a year or so after the birth of their child (50,63,65). However, average weight gains mask the fact that around 10-15 of women remain at least 5 kg heavier after pregnancy than they were before conception (49,50,54,65). In a contemporary study of 243 first time mothers (50), no significant increase in mean maternal body weight was observed following pregnancy, yet the 10 of women with the highest pregnancy-related weight gains were nearly 9 kg (8.95 kg) heavier at least 1 year after delivery (Figure 20.4). Long-term weight changes following pregnancy have been shown to range from a weight loss of 13.6...

Risk Factors For Maternal Obesity

Since most women return (or get close) to their pre-pregnant weight after pregnancy (50), the compelling question is not whether women return to their pre-pregnant weight, but rather which women fail to return to their pre-pregnant weight and why Several studies have revealed a variety of important risk factors that explain why some women experience persistent weight gains following pregnancy, while others remain unaffected. Broadly speaking, these risk factors can be split into four main groups Excessive gestational weight gain is by far the most important risk factor associated with the period of pregnancy (50,61,71,72). This is of particular concern today as weight gain recommendations for pregnancy have recently increased (6). Following a review of the scientific literature published in the 1970s and 1980s, the US Institute of Medicine proposed new guidelines for maternal weight gain based on pre-pregnant body mass index (see Table 20.3). There is however, concern that these...

Magnetic Resonance Imaging Of Temporal Lobe Epilepsy

As we have discussed when reviewing the pathology of TLE with HS above, HS must be thought of as damage to the formed hippocampus (156). Pathologically it consists of loss of normal tissue (neuron loss and macroscopic atrophy) and gliosis and reorganization. In other words, it is a scar that appears to have occurred after the hippocampus was formed. Whether the event that caused this damage occurred in utero (making HS a 'developmental lesion') or after birth (an 'acquired lesion') is largely a semantic rather than an etio-logic argument. A similar pattern of 'damage' can be induced in a range of animal models and human disease from a variety of stimuli that can be considered to be neurotoxic.

Diseases Causing Intestinal Failure

In pediatric patients, most frequent causes of short-bowel syndrome are malrotation, volvulus, necrotizing enterocolitis, jejunoileal artresias, gas-troschisis, and omphalocele among other congenital disorders. Transplant candidacy has to be considered in the context of alternatives to transplantation including the potential for rehabilitation or successful lifelong parenteral nutrition. In a large series, about 20 of adult patients with less than 100 cm of residual intestine could be weaned from TPN. In children, less than 30 cm of jejunoileum, lack of entero-colonic continuity, and lack of feeding tolerance early after birth correlate to failure of weaning from parenteral nutrition 14 .

Specific Transporters in the Small Intestine Take Up Amino Acids and Peptides

In adults, a negligible amount of protein is absorbed as undigested protein. In some individuals, however, intact or partially digested proteins are absorbed, resulting in ana-phylactic or hypersensitivity reactions. The pulmonary and cardiovascular systems are the major organs involved in anaphylactic reactions. For the first few weeks after birth, the newborn's small intestine absorbs considerable amounts of intact proteins. This is possible because of low prote-olytic activity in the stomach, low pancreatic secretion of peptidases, and poor development of intracellular protein degradation by lysosomal proteases.

Pregnancy Shares Many Cardiovascular Characteristics With the Trained State

Regular exercise may reduce the risk of spontaneous abortion of a chromosomally normal fetus. Continued exercise throughout pregnancy characteristically results in normal-term infants after relatively brief labor. These infants are usually normal in length and lean body mass but reduced in fat. The risk of large infant size for gestational age, increased in diabetic mothers, is reduced by maternal exercise through improved glucose tolerance. The incidence of umbilical cord entanglement, abnormal fetal heart rate during labor, stained amniotic fluid, and low fetal responsiveness scores may all be reduced in women who are active throughout pregnancy. Further, when examined 5 days after birth, newborns of exercising women perform better in their ability to orient to environmental stimuli and their ability to quiet themselves after sound and light stimuli than weight-matched children of nonexercising mothers.

Physical Characteristics of Rabbits Hares and Pikas

Lagomorphs can yield two or more litters during each breeding season, with two or three litters common among hares and pikas and three to six among rabbits. Litter size ranges between two and eight. Young rabbits are altricial and are cared for in a nest. Hares are born in the open and are precocial, able to run soon after birth.

How the O2O3 Mixture Works

The nucleus pulposus can set off an immune-mediated inflammatory process. The proteoglycan component of the nucleus is largely isolated from the immune system after birth. Herniation of a fragment of the nucleus pulposus may trigger an autoimmune reaction and generate an inflammatory process whose cellular component is mainly supported by macrophages. A non-immune-mediated mechanism of inflammation may be created by the nucleus, which reacts with surrounding histiocytes, fibroblasts, and chondrocytes to produce cytokines (interleukin 1a, interleukin-6, and tumor necrosis factor a) with an increase in phospholipase A2 leading to the release of prostaglandin E2, leukotrienes, and thromboxanes. In small amounts, prostaglandins enhance sensitivity of the nerve roots and other pain-producing substances like bradykinin. Experimental studies have shown that an oxygen-ozone gas mixture at the concentrations used for intradiscal treatment has the same effect as steroids on inhibiting cytokine...

Natural History Of

With a TEL-AML1 -driven preleukemic clone than ever become diagnosed with leukemia. This is currently being assessed by molecular screening of unselected cord blood samples. Second, something else is required after birth for cALL to develop. As with other medical studies on twins (e.g., autoimmune disease), the suspicion then falls on environmental exposures that, in this case, might provoke or promote evolution of the fetal preleukemic clones.

Some Perspectives on Intersubjectivity

Colwyn Trevarthen (1989), a biologist turned infant researcher, believes that in the human infant an intersubjective relationship, a reciprocal responsitivity, is established shortly after birth. The mother acts particularly quiet and soft if the baby is sleeping, calming if the baby acts distressed, friendly and inviting if the baby is attentive. This reciprocity of feeling is communicated through eye contact, speech, and touch. Trevarthen describes this as protoconversation. He compared this mother-infant interaction to a musical duet. There is no doubt that the infant senses the mother's intentionality.

Inulin Type Fructans and Infant Formulas

There is substantial evidence that the oligosaccharides secretion in mother's milk is a complex, variable, and dynamic process.23 Not only does the amount of oli-gosaccharides in human milk change during lactation, but the composition of their mixture also varies among different samples, being influenced by many factors. The highest amount of oligosaccharides (i.e., 20 l) is reached on day four after birth,21,22 but at days 30 and 120 of lactation, that content falls by 20 and 40 respectively, and is compensated by an increase in lactose content.21,23 Based on these considerations, and as cow's milk is very poor in oligosaccharides, it has been hypothesized that supplementing infant formulas with oligosac-charides could improve the nutritional value of formulas and help mimic some of the effects of mother's milk, especially the bifidogenic effect. Although breast-fed and formula-fed infants have similar gastrointestinal flora on day three or four after birth when it is dominated by...

Female meiosis in mammals

Female meiosis is dramatically different from that in the male. Not only is there only one gamete produced per meiotic division but meiosis occurs in two relatively brief and separate phases in females, with the phases in some species separated by many years. The first phase is during early fetal development when the primordial germ cells divide mitoti-cally to produce 30,000-75,000 oogonia. All oogonia then proceed into meiosis, reaching the diplotene stage of the first meiotic division shortly after the time of birth. In female mice, this occurs at day 5 after birth (Silver, 1995). The oogonia then become arrested at this dictyate stage, acquiring a coating of follicle cells to comprise a follicle. With the onset of puberty, hormones stimulate individual follicles or groups of follicles to mature and complete meiosis during each oestrus cycle. The first meiotic division and first polar body formation is completed prior to ovulation. The second meiotic division then stalls at...

Disease Associated With Ip3 Receptors

A deletion in the IP3R1 gene, displays epileptic-like activity (Street et al., 1997), and a less severe, but similar, ataxic phenotype is observed in the mutant mice staggerer, nervous, and Purkinje-cell degeneration, which express very low levels of IP3R1. In addition, mice in which the IP3R1 gene has been disrupted (knocked out) either die in utero or exhibit ataxia and epileptic seizures at about 9 days after birth and die before weaning (Matsumoto et al., 1996). Thus IP3R1 is essential for normal brain function.

Molecular Regulation Of Limb Development

Phocomelia Babies

Congenital hip dislocation consists of underdevelopment of the acetabulum and head of the femur. It is rather common and occurs mostly in females. Although dislocation usually occurs after birth, the abnormality of the bones develops prenatally. Since many babies with congenital hip dislocation are breech deliveries, it has been thought that breech posture may interfere with development of the hip joint. It is frequently associated with laxity of the joint capsule.

Round Ligament Of The Liver

Round Ligament Liver

The lesser omentum and falciform ligament form from the ventral meso-gastrium, which itself is derived from mesoderm of the septum transversum. When liver cords grow into the septum, it thins to form (a) the peritoneum of the liver, (b) the falciform ligament, extending from the liver to the ventral body wall, and (c) the lesser omentum, extending from the stomach and upper duodenum to the liver (Figs. 13.14 and 13.15). The free margin of the falciform ligament contains the umbilical vein (Fig. 13.10A), which is obliterated after birth to form the round ligament of the liver (ligamentum teres hepatis). The free margin of the lesser omentum connecting the duodenum and liver (hep-atoduodenal ligament) contains the bile duct, portal vein, and hepatic artery (portal triad). This free margin also forms the roof of the epiploic foramen of

Immunological Tolerance

One of the earliest insights into these questions was made by Ray Owen in 1945. Owen was studying an interesting type of twin in cattle called a freemartin. Freemartins are genetically distinct ( fraternal ) twins.1 Normally, fraternal twins each have their own placenta, isolating them from each other while in utero. But freemartin fraternal twins share a common placenta. The fact that they are connected by blood during fetal life means that as embryos they share everything that moves around in the bloodstream. The cells of the blood mix freely prior to birth, and after birth each twin has a mixture of two genetically different types of blood. Even the stem cells from which all blood cells derive mix between the twins. As a result, this state of mixed blood types persists for life. But freemartin twins are completely tolerant of each other's blood, no matter how genetically disparate they are, for life. They can also exchange other cells and tissues with relative impunity. This led to...

Because Snapdragons Possess The Pigment Anthocyanin They Have Reddish Purple Petals. Two Pure Anthocyaninless

When rabbits with the Pelger anomaly were mated to each other, Nachtsheim found 223 normal progeny, 439 showing the Pelger anomaly, and 39 extremely abnormal progeny. These very abnormal progeny not only had defective white blood cells, but also showed severe deformities of the skeletal system almost all of them died soon after birth. In genetic terms, what do you suppose these extremely defective rabbits represented Why do you suppose there were only 39 of them

Clinical Aspects of PPHN

As described above, autopsy studies of fatal PPHN demonstrate severe hypertensive structural remodeling even in newborns who die shortly after birth, suggesting that many cases of severe disease are associated with chronic intrauterine stress (Fig. 3B). However, the exact intrauterine events that alter pulmonary vascular reactivity and structure are poorly understood. Epidemiologic studies have demonstrated strong associations between PPHN and maternal smoking and ingestion of cold remedies that include aspirin or other non-steroidal anti-inflammatory products (83). Since these agents can induce partial constriction of the DA ), it is possible that pulmonary hypertension due to DA narrowing contributes to PPHN (see below). Other perinatal stresses, including placenta previa and abruption, and asymmetric growth restriction, are associated with PPHN however, most neonates who are exposed to these prenatal stresses do not develop PPHN. Circulating levels of L-arginine, the substrate for...

Descent Of The Testes

Fascia The Peritoneal Cavity

A. During the second month. B. In the middle of the third month. Peritoneum lining the coelomic cavity evaginates into the scrotal swelling, where it forms the vaginal process (tunica vaginalis). C. In the seventh month. D. Shortly after birth. E. Scanning electron micrograph of a mouse embryo showing the primitive gonad (C), mesonephric duct (arrowheads), and gubernaculum (arrows). Figure 14.40 Descent of the testis. A. During the second month. B. In the middle of the third month. Peritoneum lining the coelomic cavity evaginates into the scrotal swelling, where it forms the vaginal process (tunica vaginalis). C. In the seventh month. D. Shortly after birth. E. Scanning electron micrograph of a mouse embryo showing the primitive gonad (C), mesonephric duct (arrowheads), and gubernaculum (arrows). The connection between the abdominal cavity and the processus vaginalis in the scrotal sac normally closes in the first year after birth (Fig. 14.40D). If...

Regulation of Gap Junction Channels

The degree of coupling between participating cells is highly plastic. Long-term regulation, such as that which occurs during development, is achieved by changes in the level of connexin expression. For example, Cx26, but not Cx32, is expressed in embryonic brain, whereas after birth there is reciprocal upregulation of Cx32 and downregulation of Cx26 (Dermietzel et al., 1989). Short-term regulators of gap junction coupling influence channel gating. They include second messengers such as cyclic AMP, which opens gap junction channels and so enhances coupling, and ions such as Ca2+ or H+, which rapidly close gap junctions and decrease coupling. Variations in the membrane potential of coupled cells, or in the phosphorylation state of the cell, also influence gap junction gating. Different connexins vary in their sensitivity to these short-term regulators.

Endocrine Aspects Of Testicular Descent

Fsh Testosterone

The hypothalamic-pituitary-testicular axis differentiates by midgestation. Testosterone, gonadotropins, and Mullerian-inhibiting hormone are present in the fetal circulation, and each could play a crucial role in testicular descent. During the first few months after birth, the hypothalamic-pituitary-testicular axis is active, with near-adult circulating levels of testosterone that peak between 1 to 3 mo of age. Thereafter, concentrations diminish gradually to low childhood levels by 6 mo of age (64). This neonatal testosterone rise is likely to be related to imprinting maleness and may be critical for normal differentiation of germ cells, as well as the spontaneous descent of undescended testes that occurs during the first 6 mo of life in males born with maldescent. These observations and the testosterone secretion pattern are also consistent with the finding that testes that fail to descend within the first 6 mo of life are unlikely to descend spontaneously thereafter.

Macerating Action Amniotic Fluid

During the first 3 months of development, the epidermis is invaded by cells arising from the neural crest. These cells synthesize melanin pigment, which can be transferred to other cells of the epidermis by way of dendritic processes. After birth, these melanocytes cause pigmentation of the skin (Fig. 18.1 D).

Regulators That Control Genes Of The Vertebrate Immune Systems

Lymphoid Development And Ikaros

In fetal life, especially, mouse T- and B-cells arise from precursors that may also give rise to macrophages, although not to other blood cell types (67,68). Many fetal T-cell precursors can still give rise to mixed T myeloid clones even though they cannot give rise to B-cells, and the reverse is true for B-cell precursors (69). There are numerous cases of cell lines that appear to be immortalized B macrophage precursors, and recently a naturally occurring cell population in the bone marrow that expresses many B-lineage properties has been shown to be able to generate macrophages or dendritic cells, which play key sentinel roles in the innate immune system (70,71). Mouse and human T-cell precursors after birth similarly retain the ability to differentiate into dendritic cells until they start undergoing antigen receptor gene rearrangement (72-75). Yet another fate as an innate immune system effector is available to T-cell precursors as well that of becoming a natural killer (NK) cell....

Globoid Cell Leukodystrophy Krabbe Disease

Krabbe Disease Symptoms

To date, early-onset GLD has invariably proved fatal. The problem with early-onset forms of GLD is that neuropathological changes are already present in the second trimester of pregnancy and that any form of treatment is applied to an already damaged nervous system. Hematopoietic stem cell transplantation to infantile patients who are already clinically symptomatic has not resulted in beneficial effects. Reports on hematopoietic stem cell transplantation very soon after birth, before the onset of any clinical symptoms, are appearing, and the results are promising but must be confirmed in larger studies. Hematopoietic stem cell transplantation is now performed in increasing numbers of patients with later onset forms. Stabilization and improvement of clinical symptoms and MRI abnormalities have been reported. Early treatment, while the intellect is still intact and the motor disabilities are only mild, is essential.

Primary Sex Organtestis

(2) Covering the glans ( head ) of the penis is a fold of skin called the prepuce. In many cultures, the prepuce is removed shortly after birth in the procedure called circumcision. At the base of the glans, there are glands that secrete a lipid-like material called smegma. Thus, there is a need for continual cleanliness.

And Laboratory Investigations

ISSD is a rare disorder, presenting in the neonatal period with coarse facial features, hepatospleno-megaly, and often ascites or hydrops. Cardiomegaly and heart failure may also be present. The patients usually display generalized hypotonia. The subsequent clinical course is invariably characterized by failure to thrive and grossly delayed development. Most patients have hypopigmented skin and fair hair. Albinoid fundi and optic atrophy may be present. Mild hypertrophy of the tongue and gums may be seen. A nephrotic syndrome may complicate the course of the disease. Spastic tetraparesis develops with increased muscle tone and hyperactive tendon reflexes. Seizures may occur. There are recurrent respiratory tract infections. Hypothyroidism has been reported infrequently. The age at death varies from soon after birth to 5 years of age.

Ang Iimediated Signaling Pathways

Ip3 And Dag Pathway

The second major isoform of the Ang II receptor, AT2, has been cloned in a variety of species, including human (53), rat (54), and mouse (38). AT2 is also a seven-transmembrane glycoprotein, encoded by a 363-amino-acid protein with a molecular mass of 41 kDa, and shares only 34 sequence identity with ATj (55). The AT2 receptor gene is localized as a single copy on the X chromosome. Unlike ATp there is no evidence for subtypes of AT2. AT2 is normally expressed at high levels in developing fetal tissues, and decreases rapidly after birth (56). In the adult, AT2 expression is detectable in the pancreas, heart, kidney, adrenals, myometrium, ovary, brain and vasculature. AT2 is re-expressed in adults after vascular and cardiac injury and during wound healing and renal obstruction (57-60). Thus, AT2 receptors appear to be involved in the control of cell proliferation, cell differentiation and development, angiogenesis, wound healing, tissue regeneration, and even apoptosis, namely,...

Pulmonary Circulation and Ventilation Perfusion Ratios

Tery to the aorta through the ductus arteriosus (described in chapter 13). After birth, the foramen ovale and ductus arteriosus close, and the vascular resistance of the pulmonary circulation falls sharply. This fall in vascular resistance at birth is due to (1) opening of the vessels as a result of the subatmospheric in-trapulmonary pressure and physical stretching of the lungs during inspiration and (2) dilation of the pulmonary arterioles in response to increased alveolar Po2.

The Life Cycle of Baleen Whales

Whales Life Cycle

Young whales are weaned between one and two years after birth, the age at which most of them leave their mothers. A whale is an adult, capable of reproduction, by six to ten years of age. The life spans of whales vary with maximum species size. The smaller species can live for thirty to forty years. The largest species can live for as long as eighty years. As with all other wild animals, not all whales in fact, relatively few of them survive to the ripe old ages noted.

Ann Munier MS RD and Frances Rohr MS RD

Inborn errors of metabolism are inherited disorders caused by a defect in enzymes required to metabolize protein, carbohydrate. or fat. The inheritance of most metabolic disorders is autosomal recessive and the incidence uncommon. Many of the disorders result in severe clinical manifestations that often appear soon after birth. Rapid diagnosis and treatment are essential to prevent neurologic damage, mental retardation, and possible death. Because these disorders are rare and require careful monitoring of metabolic stability, individuals afflicted with them are best served by clinics specializing in inherited metabolic disorders. Referral centers are listed in Appendix C.

Neonatal Leydig Cells

Just after birth, the number of Leydig cells again increases to a peak at 2 to 3 mo of age, contributing to a second surge in plasma testosterone levels. At this stage, Leydig cells contain abundant SER membranes and mitochondria, as well as varying amounts of lipid droplets (4,24-27). In the neonatal testis, fetal Leydig cells persist through at least 3 mo after birth. Postnatal increase in the number of these cells most likely results from recruitment of interstitial precursor cells. After this increase, neonatal Leydig cell numbers regress rapidly to a nadir by the end of the first year. The neonatal period is relatively brief, extending only through the first year of life (28,29). Fig. 3. Human Leydig cell development. FLC, fetal Leydig cells NLC, neonatal Leydig cells ILC, immature Leydig cells ALC, adult Leydig cells, P, fibroblastic precursors of Leydig cells. The cross-hatched circles indicate degeneration of FLC, NLC, and ALC. The far left-hand column of the compartments...

Genetically Engineered Animals

The simplest method of making a transgenic animal is inject a fertilized mouse oocyte with DNA encoding the gene of interest and an appropriate promotor. The oocyte is then implanted into a pseudopregnant mouse and, with luck, some of the offspring will express the transgene. The first generation mice will be heterozygotes, but homozygous mice can be obtained by selective breeding. One problem with this method is that it is rather inefficient, since only 10-30 of offspring are likely to carry the transgene and these cannot be identified until after birth. Another is that the foreign DNA integrates randomly into the genome, which may have undesirable consequences. For example, if the transgene inserts into the coding region of another gene it may disrupt its function, which complicates interpretation of the function of the transgene. Whether or not the transgene expresses also depends on its position in the chromosome.

Compare Unexposed Disease Rates to External Populations

In selected areas of the country, congenital malformations are comprehensively tabulated and data on prevalence at birth are published. Information from vital records, including birth records (birth weight, duration of gestation) and death data used to generate cause-specific mortality, constitutes a national registry for the United States and provides a readily available benchmark for studying health events that can be identified in such records. Yet the ascertainment methods even for these relatively well-defined conditions can differ markedly between a given research protocol and the vital records protocol. For example, identification of congenital malformations depends strongly on whether medically indicated abortions are included or excluded as well as the frequency of such abortions, how systematically newborn infants are examined, how far into life ascertainment is continued (many malformations only become manifest some time after birth), etc. Cumulatively, those differences...

Inhibition of cADPRdependent Dilation by Hypoxia

Regulation by cADPR ofCa2+release from an SR compartment proximal to the plasma membrane may, however, have wider implications. For example, a P02 window for cADPR accumulation by hypoxia may also underpin 02-induced pulmonary artery dilation after birth, which has been shown to be mediated, at least in part, by opening of BKCa channels and smooth muscle hyperpolarization (49). In addition, the relatively low level of the enzyme activities for cADPR synthesis and metabolism in systemic artery smooth muscle, may point to a role for cADPR-dependent recruitment of BK channels in hypoxia-induced systemic artery dilation. If this is the case, however, the Po2-dependence of cADPR accumulation, the spatial organization of the Ca2+ mobilizing pathways, and the ability of systemic artery smooth muscle to retain peripheral SR Ca2+ stores under hypoxia may also be determining factors.

Hemolytic Disease of the Newborn Is Caused by Type II Reactions

Effect Rhogam Maternal Antibodies

If hemolytic disease caused by Rh incompatibility is detected during pregnancy, the treatment depends on the severity of the reaction. For a severe reaction, the fetus can be given an intrauterine blood-exchange transfusion to replace fetal Rh+ red blood cells with Rh- cells. These transfusions are given every 10-21 days until delivery. In less severe cases, a blood-exchange transfusion is not given until after birth, primarily to remove bilirubin the infant is also exposed to low levels of UV light to break down the bilirubin and prevent cerebral damage. The mother can also be treated during the pregnancy by plasmapheresis. In this procedure, a cellseparation machine is used to separate the mother's blood into two fractions, cells and plasma. The plasma containing the anti-Rh antibody is discarded, and the cells are reinfused into the mother in an albumin or fresh-plasma solution.

Electrical Activity of the Heart and the Electrocardiogram

Blood Flow Pattern The Human Heart

The lungs of a fetus are collapsed, and blood is routed away from the pulmonary circulation by an opening in the interatrial septum called the foramen ovale (fig. 13.15) and by a connection between the pulmonary trunk and aorta called the ductus arteriosus (fig. 13.16). These shunts normally close after birth, but when they remain open (are patent), murmurs can result. Since blood usually goes from left to right through these shunts, the left ventricle still pumps blood that is high in oxygen. When other defects are present that increase the pressure in the right pump (as in the tetralogy of Fallot), however, a significant amount of oxygen-depleted blood from the right side of the heart may enter the left side. The mixture of oxygen-poor blood from the right side with oxygen-rich blood in the left side of the heart lowers the oxygen concentration of the blood ejected into the systemic circulation. Since blood low in oxygen imparts a bluish tinge to the skin, the baby may be born...

Substantial Amounts of Calcium and Phosphate Enter and Leave Bone Each

Bone Growth Osteoid Mineralized Bone

The epiphyseal plate is a region of growing bone of particular interest because it is here that the elongation and growth of bones occurs after birth. Histologically, the epi-physeal plate shows considerable differences between its leading and trailing edges. The leading edge consists primarily of chondrocytes, which are actively engaged in the synthesis of cartilage of the epiphyseal plate. These cells gradually become engulfed in their own cartilage and are replaced by new cells on the cartilage surface, allowing the process to continue. The cartilage gradually becomes calcified, and the embedded chondrocytes die. The calcified cartilage begins to erode, and osteoblasts migrate into the area. Osteoblasts secrete osteoid, which eventually becomes mineralized, and new mature bone is formed. In the epiphyseal plate, therefore, the continuing processes of cartilage synthesis, calcification, erosion, and osteoblast invasion result in a zone of active bone formation that moves away from...

Secular Trends in Pubertal Development

Prepuberty Puberty Gnrh

Luteinizing hormone (LH) and follicle-stimulating hormone secretion rise during the first month after birth, probably because the negative feedback effect of placental estrogens are withdrawn (see Figs. 1 and 2). LH is secreted in pulses during this postnatal period (6). By the age of 6 to 12 mo, the GnRH pulse generator becomes quiescent, and gonadotropin levels decrease. However, LH pulses can be detected throughout childhood, with highly sensitive immunofluorometric methods (7,8).

Common abnormalities

Aortic Diastolic Murmur

Continuous murmurs are rare in adults. The commonest cause is a patent arterial duct which connects the upper descending aorta and pulmonary artery, and normally closes just after birth. The murmur is best heard at the upper left sternal edge, radiating to the left scapula. Its continuous character has been described as machinery-like (Fig. 3.34).

Cardiac Malformations Cx43

Arteries is impeded and the mice die shortly after birth from a failure to oxygenate the blood (Reaume et al., 1995). The phenotype of the Cx43 knockout mouse resembles a human disorder known as familial visceroatrial hetero-taxia (VAH), which is characterised by multiple malformations, including gross cardiac malformation. This raises the question of whether VAH is caused by mutations in Cx43. There is currently controversy on this issue. Mutations in Cx43 have been identified in some patients with familial VAH (Britz-Cunningham et al., 1995). However, a number of subsequent studies of other patients with familial defects of cardiac laterality have failed to find associated Cx43 mutations (Splitt et al., 1995). One possible explanation for these disparate findings is that visceroatrial heterotaxia shows significant genetic heterogeneity and that Cx43 mutations are not a major cause of the disorder.

Aberrant Adaptive Immunity in Lupus

Vertebrates acquire adaptive immunity after birth, which is a response to specific antigens that involves B and T cells of the immune system and frequently leads to a state of immune memory (Iwasaki and Medzhitov 2004). The adaptive immune system produces antibodies and T cells that are highly specific for a particular pathogen (or antigen). The relative specificity of SLE sera to a selected subset of nuclear antigens (as opposed to reacting to the whole universe of antigens) suggests that lupus genes must be impacting adaptive immunity at some level. Our recent genetic dissection studies have indicated that Sle1z may be one such locus gene (Figure. 1).

GH Regulates Growth During Childhood and Remains Important Throughout Life

Dehydration Negative Feedback

As its name implies, growth hormone (GH) promotes the growth of the human body. It does not appear to stimulate fetal growth, nor is it an important growth factor during the first few months after birth. Thereafter, it is essential for the normal rate of body growth during childhood and adolescence.

Ongenital and Perinatal Viral Infections

Cytomegalic Inclusion Disease

In contrast to these congenital (prenatal) infections, several other viruses may infect the fetus during or shortly after birth (Table 36-11). Such perinatal (alias neonatal, natal, or intrapartum) infections may be acquired during passage of the baby through an infected birth canal (herpes simplex, cytomegalovirus) or by contamination with feces (coxsackie B, echovirus 11). Disseminated neonatal herpes, disseminated varicella-zoster, and myocarditis of the newborn (Fig. 23-5) are all overwhelming generalized infections with high case-fatality rates these are usually primary maternal infections, and because

Circulatory Changes At Birth

To summarize, the following changes occur in the vascular system after birth (Fig. 11.48) Closure of the umbilical arteries, accomplished by contraction of the smooth musculature in their walls, is probably caused by thermal and mechanical stimuli and a change in oxygen tension. Functionally the arteries close a few minutes after birth, although the actual obliteration of the lumen by fibrous proliferation may take 2 to 3 months. Distal parts of the umbilical arteries form the medial umbilical ligaments, and the proximal portions remain open as the superior vesical arteries (Fig. 11.48). Closure of the umbilical vein and ductus venosus occurs shortly after that of the umbilical arteries. Hence blood from the placenta may enter the newborn for some time after birth. After obliteration, the umbilical vein forms the ligamentum teres hepatis in the lower margin of the falciform ligament. The ductus venosus, which courses from the ligamentum teres to the inferior vena cava, is also...

Preening More than Good Looks

Which is the selfless delivery of service from one animal to another. Whenever one observes a parent grooming its young, the conclusion is that the motive behind the act is to tend to the health of the infant or young, which promotes the proliferation of the species. Nearly all mammals and many species of birds display this behavior. With marsupial births, the young of the Virginia opossum are in a semiembryonic state. The mother licks the embryon at birth so that the membrane encasing it will break. She then licks a trail from the birth canal to the pouch so that the neonate, using its developed olfactory senses, can find its way to the pouch without further aid by the mother. In altricial and semialtricial placental mammals, the young are usually born naked or with little fur. Most of these animal types, such as cats, dogs, mice, shrew, rats, and hamsters, lick the newborn to remove the birth membrane, break the umbilical cord, and eat the placenta after birth. They lick the newborn...

Role in pathophysiology of hypertension and cardiovascular disorders

ANP affects blood pressure directly through its natriuretic, diuretic, and vasodilatory actions (187). It also affects blood pressure indirectly, for example, by inhibiting the RAAS, which is known to cause hypertension and cardiovascular diseases, if excessively stimulated (266). Genetic defects that reduce the activity or influence the ANP-NPRA system greatly contribute to the development of hypertension. The mechanistic role of ANP-NPRA system in counteracting the pathophysiology of hypertension is not well understood. Although the expression of ANP and BNP is markedly increased in patients with hypertrophic or failing heart, it is unclear if the NP system is activated to play a protective role by reducing the detrimental effects of high blood pressure caused by sodium retention and fluid volume, inhibiting the RAAS, or it is simply a consequence of the hypertrophic changes occurring in heart. Recent studies indicated that intrarenal renin in newborn Npr1 homozygous null mutant...

The Onset of Puberty Depends on Maturation of the Hypothalamic GnRH Pulse Generator

After birth, the newborn is deprived of maternal and pla-cental steroids. The reduction in steroidal negative feedback stimulates gonadotropin secretion, which stimulates the gonads, resulting in transient increases in serum testosterone in male infants and estradiol in females. FSH levels in females are usually higher than those in males. At approximately 3 months of age, the levels of both gonadotropins and gonadal steroids are in the low-normal adult range. Circulating gonadotropins decline to low levels by 6 to 7 months in males and 1 to 2 years in females and remain suppressed until the onset of puberty.

Parainfluenza Viruses

Several types of experimental parainfluenza type 3 vaccines have shown some degree of protection in rodent or primate models. However, formidable problems militate against parainfluenza vaccines achieving wide acceptability. First, the immunity that follows natural infection with parainfluenza viruses is poor, and it is unrealistic to expect any vaccine to do more than limit the challenge virus to the upper respiratory tract. Second, in order to protect infants during the first months of life when parainfluenza 3 can be a threat, any vaccine would need to be administered shortly after birth, when immune responses are weakest and maternal antibodies are present. Third, in light of

How Would You Test The Dna Of The Older Brother To Determine Whether He Is A Carrier For Cystic Fibrosis

In the past, it was common for people with phenylketonuria (PKU) who were placed on a low-phenylalanine diet after birth to be allowed to return to a normal diet during their teenage years. Although the levels of phenylalanine in their blood were high, their brains were thought to be beyond the stage of being harmed. If a woman with PKU becomes pregnant, however, a problem arises. Typically, the fetus is heterozygous but is unable at early stages of development to metabolize the high levels of phenylalanine that arrive from the mother's blood. Why is the fetus heterozygous What do you think would happen to the fetus during this maternal PKU situation What would be your advice to a woman with PKU who wants to have a child

Distribution of at2 receptors

In fetal tissues, the AT2 receptor is highly expressed and indeed predominates over the expression of ATi receptors (7,20,21). However, shortly after birth, AT2 receptor expression diminishes rapidly leaving the AT1 receptor predominant in adult life. Although the AT2 receptor is a low-copy receptor with barely detectable levels of mRNA in most tissues during adulthood, the AT2 receptor protein is easily detectable by Western blot in heart, blood vessels, and kidney in adults. In this respect, AT2 receptor expression resembles that of the dopamine Di receptor with very low mRNA but readily detectable protein (22). Although there is a relatively low level of AT2 receptor expression in adult tissues, the AT2 receptor predominates at certain tissue sites, including uterus, ovary, adrenal zona glomerulosa and medulla, and in distinct areas of the brain (7,23,24). The distribution of AT2 receptors in the cardiovascular and renal systems is briefly reviewed as follows.

Prolactin Regulates the Synthesis of Milk

Lactation is the final phase of the process of human reproduction. During pregnancy, alveolar cells of the mammary glands develop the capacity to synthesize milk in response to stimulation by a variety of steroid and pep-tide hormones. Milk synthesis by these cells begins shortly after childbirth. To continue to synthesize milk, these cells must be stimulated periodically by prolactin (PRL), and this is thought to be the main physiological function of PRL in the human female. What role, if any, PRL has in the human male is unclear. It is known to have some supportive effect on the action of androgenic hormones on the male reproductive tract, but whether this is an important physiological function of PRL is not established.

Sertoli Cells Have Multiple Functions

During the fetal period, Sertoli cells and gonocytes form the seminiferous tubules as Sertoli cells undergo numerous rounds of cell divisions. Shortly after birth, Sertoli cells cease proliferating, and throughout life, the number of sperm produced is directly related to the number of Sertoli cells. At puberty, the capacity of Sertoli cells to bind FSH

Box 2 Risk factors associated with poor antiHBs response to hepatitis B vaccine

Perinatal immunoprophylaxis with hepatitis B vaccine is now routinely given to newborn infants, with an additional early dose of HBIG for those who are born to HBV-infected mothers. The use of HBIG alone does not provide long-term protection against the infection 16 . The vaccine series should be initiated within the first 12 hours after birth for neonates born to HBsAg-positive mothers but may be administered by a relatively flexible schedule to those born to HBsAg-negative women 67 . With immunization, more than 95 of babies develop anti-HBs titer 10 mlU mL 68,69 . Vaccinated infants of HBsAg-positive mothers should then be tested for HBV status at 12 months of age. Without immunization, 90 would be chronically infected due to vertical transmission of HBV 7 . As for adult vaccinees, hepatitis B vaccine affords long-term protection for most infants when initiated soon after birth 16,70 , Even if children lose detectable anti-HBs later on in life, which occurs in up to half of...

Congenital Hypogonadotropic Hypogonadism Caused by Genetic Defects of the Gonadotropin Subunit Genes Mutation in the

A single case report from this institution described a male who had an inactivating mutation of the LH-P subunit (99). The proband presented at the age of 17, with delayed puberty. He was from a family with several infertile male members. T levels were reduced in association with elevated LH and FSH levels. Testicular biopsy revealed spermatogenic arrest and absent Leydig cells. Long-term hCG therapy induced testicular growth and spermatogenesis. The mutant hormone had normal immunoreactivity but no biologic activity. These findings, together with the occurrence of infertility in three maternal uncles, suggested a genetic defect in the LH structure. A homozygous mutation of the LH-P subunit, A to G missense mutation, was found in codon 54, causing a Glu to Arg substitution. The proband's mother, sister, and uncles were heterozygous for the mutation. Coexpression of the mutated LH-P gene with the normal a-subunit gene in CHO cells resulted in the formation of immunoreactive LH a p...

Animal Growth and Development

An organism's growth occurs because of the increasing number of cells that form as well as because of the increasing size of individual cells. For example, a mouse increases from a single cell, the zygote, to about three billion cells during the period from fertilization to birth. Embryology is the study of the growth and development of an organism occurring before birth. Growth and development, however, continue after birth and throughout adulthood. Growth ceases only at death, when the life of the individual organism is ended. The bone marrow of human adults initiates the formation and development of millions of red blood cells every minute of life. About one gram of old skin cells is lost and replaced by new cells each day.

The Fetal Endocrine System Gradually Matures

The protective intrauterine environment postpones the initiation of some physiological functions that are essential for life after birth. For example, the fetal lungs and kidneys do not act as organs of gas exchange and excretion because their functions are carried out by the placenta. Constant isothermal surroundings alleviate the need to expend calories to maintain body temperature. The gastrointestinal tract does not carry out digestive activities, and fetal bones and muscles do not support weight or locomotion. Being exposed to low levels of external stimuli and environmental insults, the fetal nervous and immune systems develop slowly. Homeostasis in the fetus is regulated by hormones. The fetal endocrine system plays a vital role in fetal growth and development. The fetal adrenal glands are unique in both structure and function. At month 4 of gestation, they are larger than the kidneys, as a result of the development of a fetal zone that constitutes 75 to 80 of the whole gland....

Genetic Influences on the Cloning Process

When ES cells derived from several mouse strains were used as nuclear donors, inbred 129, C57 B6 and a variety of F1 ES cell lines all gave rise to newborn clones (Wakayama et al. 1999 Rideout et al. 2000 Eggan et al. 2001). However, clones from the inbred ES cell lines died shortly after birth due to respiratory failure (Wakayama et al. 1999 Rideout et al. 2000 Eggan et al. 2001). In contrast, most clones derived from five different F1 ES cell lines survived to adulthood (F1 here refers to ES cell lines derived from embryos produced by intercrossing parents with different inbred genetic backgrounds (Rideout et al. 2000 Eggan et al. 2001)).

Epidemiologic assessment

Because of the difficulties in obtaining the samples, the need for multiple samples and the increasing reliance on FHR patterns, there has been a progressive diminution in the use of this technique 46 . Assessment of umbilical cordpH andblood gases immediately after birth is widely used to assess the acid-base balance of the fetus in utero just before delivery. To properly interpret fetal scalp and umbilical cord blood gases, there must be an understanding of numerous technical pitfalls that can compromise interpretation of both the timing and severity of fetal hypoxia. These may include (a) internal inconsistency in the analysis of a blood gas sample (b) blood gas samples (labeled 'artery' and 'vein') may actually derive from the same vessel, or the reporting of the results may be reversed or (c) the samples may be contaminated with an air bubble(s). On occasion, only a single sample or only a single pH may be available. Unless both an umbilical venous and an umbilical arterial...

Congenital Heart Disease

Structural abnormalities of the heart or intrathoracic great vessels seem to affect 8 to 10 of every 1000 infants born alive in the United States. If bicuspid aortic valves and mitral valve prolapse manifested later in life are included, the rate may well exceed 1 percent of live births. About 1 newborn per 1000 live births has a cardiac birth defect that cannot be managed medically or surgically. Most infants who previously would have died now survive to adult life because of improved treatment, but 5 to 6 of these infants per 1000 live births require frequent medical or surgical attention shortly after birth or later in childhood. In 1997, deaths in infancy from congenital cardiovascular disease occurred at the rate of 0.5 per 1000 live births, about one-half the rate that occurred in 1980.8 The 1-year fatality rate among the estimated 32,000 new cases at birth each year was about 6.5 percent in 1997. About 25 percent of infants with congenital heart disease have a malformation...

The Placental Vasculature Permits Efficient Exchanges of O2 and CO2

Special fetal adaptations are required for gas exchange, particularly oxygen, because of the limitations of passive exchange across the placenta. The PO2 of maternal arterial blood is about 80 to 100 mm Hg and about 20 to 25 mm Hg in the incoming blood in the umbilical artery. This difference in oxygen tension provides a large driving force for exchange the result is an increase in the fetal blood PO2 to 30 to 35 mm Hg in the umbilical vein. Fortunately, fetal hemoglobin carries more oxygen at a low PO2 than adult hemoglobin carries at a PO2 2 to 3 times higher. In addition, the concentration of hemoglobin in fetal blood is about 20 higher than in adult blood. The net result is that the fetus has sufficient oxygen to support its metabolism and growth but does so at low oxygen tensions, using the unique properties of fetal hemoglobin. After birth, when much more efficient oxygen exchange occurs in the lung, the newborn gradually replaces the red cells containing fetal hemoglobin with...

Aetiology and Risk Factors

The effect of pregnancy on the behaviour of intraabdominal DTs has been investigated in retrospective studies. Some authors have shown a tendency for DTs to develop soon after pregnancy 30, 33, 34 , but others find that DTs present later, are smaller and significantly less aggressive in females who have been pregnant than in females who have not 35 . These authors suggest that hormones of pregnancy such as progesterone or prolactin, could have a beneficial effect and suggest that this type of hormonal treatment should be attempted. In their opinion, further prospective studies are needed to determine the consequences of pregnancy on DTs and the risk for a pregnant female of developing a DT, in order to advise women with a family history of DT against pregnancy 35 .

Cognitive Development

All children seem to have the potential to learn any language and, for some time after birth, generate all the sounds necessary to do so. The sequence of language development is basically the same for all languages, with environmental variables determining which language will be learned. Comprehension of language usually precedes language production. A typical pattern of language production includes cooing, followed by babbling, then one-word utterances, short telegraphic speech patterns, longer phrases, longer sentences, and finally, by about age 4, speech patterning that is very similar to that of adults. Many psychologists view language acquisition as the primary basis for thinking and memory.

Mechanisms of Pulmonary Vasodilation at Birth

Mechanisms, such as a compensatory vasodilator mechanisms (e.g., upregulation of other NOS isoforms or dilator prostaglandins) or less constrictor tone. Interestingly, these animals are more sensitive to the development of pulmonary hypertension at relatively mild decreases in Pa02 and have higher neonatal mortality when exposed to hypoxia after birth (unpublished observations). We speculate that isolated eNOS deficiency alone may not be sufficient for the failure of postnatal adaptation, but that decreased ability to produce NO in the setting of a perinatal stress (e.g., hypoxia, inflammation, hypertension, or upregulation of vasoconstrictors) may cause PPHN.

Animal Models

The original scurfy (sf) mutation, a fatal X-linked condition, has occurred spontaneously in a partially inbred strain of mice (Russell et al. 1959). Shortly after birth, affected male mice present with a scaly skin rash and severe runting secondary to chronic diarrhea and malabsorption. Characteristically, the mice exhibited lymphadenopathy, splenomegaly, massive lymphocytic infiltrates of the skin, liver, and lungs and developed hemolytic anemia associated with a positive Coombs test, suggesting that the sf mutation causes a generalized autoimmune-like syndrome. The gene responsible for the sf mutation was identified and designated as Foxp3 (Brunkow et al. 2001) consisting of a two-base-pair insertion in exon 8, resulting in a frame shift that leads to a truncated protein product lacking the carboxy-terminal fork-head domain. This sf mouse model was instrumental in the discovery of Treg cells (Fontenot et al. 2003). Using Foxp3-negative gene-targeted mice and a GFP-Foxp3...

Specific injuries

Brachial plexus injuries (obstetric palsies) are seen in 0.8 per 1000 live births following traction on the arm or head, and comprise around 40 of all birth injuries. There may be an associated fracture of the clavicle in 10-15 of cases. The diagnosis is either obvious after birth with a flail limb, or made by a high index of suspicion following a difficult delivery. Shoulder X-rays should be obtained to exclude a fracture. Three types of palsy are recognized

Birth in Cattle

A front presentation calf is born in the diver position, with its front legs stretched out and its head between them. The legs protrude about a foot, and then the head comes out, nose first. The head is soon followed by the shoulders, and then the rest of the calf slides out. Usually, afterbirth (the placenta) comes out as well. However, it may take several hours after calving for this to happen. Within a few hours after birth, the calf is ready to nurse and grow.

Physiologic Anemia

After birth the oxygen saturation is 95 , EPO is undetectable, and red cell production by day 7 is 10 of the level in utero. As a result of this, the hemoglobin level falls to a nadir at 8-12 weeks (physiologic anemia). At this point oxygen delivery is impaired, erythropoietin stimulated, and red cell production increased.

Passive Immunity

There is abundant evidence for the efficacy of antibody in preventing infection. For example, artificial passive immunization (injection of antibodies) temporarily protects against hepatitis A or B, rabies, measles, varicella, and several other viral infections (see Chapter 13). Furthermore, natural passive immunization protects the newborn for the first few months of life against most of the infections that the mother has experienced. In humans this occurs in two ways (1) maternal antibodies of the IgG class cross the placenta and protect the fetus and the newborn infant during pregnancy and for several months after birth (2) antibodies of the fgA class are secreted in the mother's milk at a concentration of 1.5 grams per liter (and considerably higher in the early colostrum), conferring protection against enteric infections as long as breast-feeding continues. If the infant encounters viruses when maternal immunity is waning, the virus replicates to only a limited extent, causing no...


It is likely that such testes are normal, and the delayed descent represents a continuum of a normal process that may extend beyond 40 wk after conception. In addition, there is a greater likelihood of descent in the 3 mo after birth if the maldescent is bilateral, suggesting a delay of the usual process, and if the scrotum is large and well developed at birth, suggesting greater stimulation by testosterone (11).

Milk Production

Although true milk is not produced during pregnancy, a precursor to milk, colostrum, can be produced in small amounts by the mammary glands of most species. Colostrum is a sticky, yellowish, transparent liquid. Colostrum secretion continues in the first few days after birth of the


Tional needs of the growing offspring. The most extreme example of the ability of the mammary gland to change the composition of milk is seen in the kangaroo. In this animal, the newborn attaches to a teat in the mother's pouch shortly after birth and remains there for a month or more. A mother kangaroo may nurse offspring of different ages from separate teats, and each teat supplies a milk with the appropriate nutritional composition for that young.


During late fetal life, the tympanic cavity expands dorsally by vacuolization of surrounding tissue to form the tympanic antrum. After birth, epithelium of the tympanic cavity invades bone of the developing mastoid process, and epithelium-lined air sacs are formed (pneumatization). Later, most of the mas-toid air sacs come in contact with the antrum and tympanic cavity. Expansion of inflammations of the middle ear into the antrum and mastoid air cells is a common complication of middle ear infections.

Why Autoimmunity

A close pursuit of this very question has led to some intriguing insights into how the immune system is put together. For example, it has been observed that the immune system, both in terms of T cells and of B cells, seems to be directed, right around the time of birth, largely against self. If we examine the antibodies in the blood of human infants just after birth, we find that a rather high percentage of them are directed at self antigens. This condition disappears a short time after birth, but it is as if, just prior to that instant when the immune system was taking that last look around to define self at birth, it was actually using self antigens to prime itself, to get itself up and going.


The hair follicle is the sac-like housing of the hair shaft. The germinative part of the hair shaft is the hair matrix (see p. 39, Fig. 2.15). Melanocytes migrate into the matrix and the melanins that they produce are responsible for the different colours of hair. Each follicle passes, independently of its neighbours, through regular cycles of growth (anagen) and resting shedding (lelogen). (he duration of these stages varying in different regions of the body. The anagen phase of scalp hair may last for up to 5 years, accounting for its length. This phase is shorter and the telogen phase longer in eyebrow and sexually determined hair. Moulting does not normally occur in humans unless the hair cycles in neighbouring follicles become synchronised, as sometimes occurs after childbirth and various pyrexic illnesses (telogen effluvium).

Fetal Circulation

Diagram Fetal Circulation

Necessitated by the high resistance of the pulmonary circulation, the fetal circulatory system has a connection between the pulmonary artery and the aorta, called the ductus arteriosus, that shunts blood from the outflow of the right heart directly into the systemic arteries. After birth, the ductus gradually closes. The ventricular chambers of the developing fetal heart are nearly equal in size. It is only after birth that the load on the left ventricle increases, necessitating additional growth of the left ventricular wall to accommodate an increased demand. To equalize the output of the two hearts, there is a small opening in the interatrial septum, called the foramen ovale. On the left side of the septum there is a small flap of tissue that allows flow from the right atrium to the left but prevents the reverse from occurring. In the fetus, this flap is open, but at birth it closes for reasons that will become clear below. Thus, immediately after birth, when the left and right...

DiGeorge Syndrome

Abnormal fetal development of the third and fourth pharyngeal pouches causes defective development of the thymus, thyroid, and parathyroids. Because of the inhibition of thymic maturation, there are low numbers of T cells in peripheral blood. Most such children die shortly after birth, death being caused by cardiac abnormalities. Abnormal parathyroid development is reflected in altered serum calcium and serum electrolyte levels. Ramifications of the altered calcium levels include muscular twitching and tetany (Webster, 1985).

Meerkat Facts

Mating generally occurs between October and April, and females give birth to two to five young after a gestational period of about seventy-seven days. Mothers give birth in a specific chamber in the burrow and young are born blind, but their eyes open in twelve to fourteen days. Meerkat young begin eating solid food at about three or four weeks of age but typically nurse for eight to twelve weeks. In meerkat society, there are many individuals who babysit young while the mothers forage for food. Meerkat young are sexually mature about one year after birth.

Mammary Glands

Mammary Line

The first indication of mammary glands is found in the form of a bandlike thickening of the epidermis, the mammary line or mammary ridge. In a 7-week embryo, this line extends on each side of the body from the base of the fore-limb to the region of the hindlimb (Fig. 18.4C). Although the major part of the mammary line disappears shortly after it forms, a small portion in the thoracic region persists and penetrates the underlying mesenchyme (Fig. 18.4A). Here it forms 16 to 24 sprouts, which in turn give rise to small, solid buds. By the end of prenatal life, the epithelial sprouts are canalized and form the lactiferous ducts, and the buds form small ducts and alveoli of the gland. Initially, the lactiferous ducts open into a small epithelial pit (Fig. 18.4B). Shortly after birth, this pit is transformed into the nipple by proliferation of the underlying mesenchyme.


Mastoid Fontanelles

Figure 8.4 Skull of a newborn, seen from above (A) and the right side (B). Note the anterior and posterior fontanelles and sutures. The posterior fontanelle closes about 3 months after birth the anterior fontanelle, about the middle of the second year. Many of the sutures disappear during adult life. Figure 8.4 Skull of a newborn, seen from above (A) and the right side (B). Note the anterior and posterior fontanelles and sutures. The posterior fontanelle closes about 3 months after birth the anterior fontanelle, about the middle of the second year. Many of the sutures disappear during adult life. At birth the flat bones of the skull are separated from each other by narrow seams of connective tissue, the sutures, which are also derived from two sources neural crest cells (sagittal suture) and paraxial mesoderm (coronal suture). At points where more than two bones meet, sutures are wide and are called fontanelles (Fig. 8.4). The most prominent of these is the anterior fontanelle, which...

Clinical Correlates

Chromosome Syndrome

The main abnormalities of trisomy 13 are mental retardation, holo-prosencephaly, congenital heart defects, deafness, cleft lip and palate, and eye defects, such as microphthalmia, anophthalmia, and coloboma (Fig. 1.10). The incidence of this abnormality is approximately 1 in 20,000 live births, and over 90 of the infants die in the first month after birth.

Pathogenesis of PPHN

Pphn Pathophysiology

Several experimental models have been studied to explore the pathogenesis and pathophysiology of PPHN (21, 54). Such models have included exposure to acute or chronic hypoxia after birth, chronic hypoxia in utero, placement of meconium into the airways ofneonatal animals, sepsis and others. Although each model demonstrates interesting physiologic changes that may be especially relevant to particular clinical settings, most studies examine only brief changes in the pulmonary circulation, and mechanisms underlying altered lung vascular structure and function ofPPHN remain poorly understood. Clinical observations that neonates with severe PPHN who die during the first days after birth already have pathologic signs of chronic pulmonary vascular disease suggest that intrauterine events may play an important role in this syndrome. Adverse intrauterine stimuli during late gestation, such as abnormal hemodynamics, changes in substrate or hormone delivery to the lung, hypoxia, inflammation or...

GM1 Gangliosidosis

Gm1 Gangliosidosis Type

Type 1 infantile GM1 gangliosidosis presents at or soon after birth, signs being poor sucking and feeding. The child is hypotonic and hypoactive and soon develops facial and peripheral edema. At times neonatal ascites and hydrocele are seen, and sometimes generalized edema. There are characteristic coarse facial features similar to those found in mu-copolysaccharidoses. Facial abnormalities include frontal bossing,wide and depressed nasal bridge,long philtrum, and large low-set ears. The gums and tongue may appear hypertrophied. The cornea is clear. Hepatomegaly is present, and the spleen is often also enlarged. The dysmorphic features and he-patosplenomegaly gave this disease its other name pseudo-Hurler disease. The skin is usually thick and rough. Exceptional cases of angiokeratoma corporis diffusum have been described. Failure to thrive and severe psychomotor retardation are early signs of the disease. Bilateral, cherry-red spots are found on the maculae in about half the...