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At least 19 recordsLinked to original sources
PubMed1979

Daily changes in the curved crown-rump length of individual sheep fetuses during the last 60 days of pregnancy and effects of different levels of maternal nutrition.

A method is described by which daily changes in the curved crown-rump length (CRL) of individual sheep fetuses were observed during the last 50 to 60 days of pregnancy. The mean discrepancy between the derived value for CRL and the CRL measured directly in eight fetuses aged between 100 and 135 days and in 12 lambs born at 143 to 150 days was 1.5 +/- 0.2 per cent (mean +/- s.e.). In adequately nourished ewes between 100 and 115 days of gestation growth rate showed a between-fetus range of 4.2 to 7.5 mm.day-1 (n=16), remained constant within each fetus until about 132 days and then decreased by about 27 per cent (n=4). Decreases in growth rate of about 30 to 44 per cent occurred within three days of the introduction of maternal undernutrition at 115 or 120 days of gestation (n=6) and in two other fetuses maternal undernutrition effected an almost complete cessation of growth. The relationship between fetal CRL and weight is described and some physiological implications of the results are discussed.

Animals↗
PubMed1979

Histological development of the equine fetal adrenal gland.

The horse fetal adrenal gland was shown to begin to increase in weight from about the end of the 4th month of pregnancy when the fetus has a crown-rump length of about 20 cm. Growth then proceeds steadily to term but, in contrast to the adult horse, the medulla remains thicker than the cortex throughout fetal life. The cortex also becomes established around 20 cm crown-rump length and at the same time the glomerular and fascicular zones become distinguishable. In contrast the reticular zone is not differentiated until around 50 cm crown-rump length. In the fetal adrenal cortex, the fascicular zone is less prominent than in the adult horse although counts of cell nuclei in the cortical region indicate hypertrophy of the fascicular cells during the last third of gestation.

Adrenal Cortex↗
PubMed1978

Double outlet right ventricle in a human embryo.

A human embryo of 14 mm crown-rump length is described to exemplify the anomaly of double outlet right ventricle with subaortic defect. The configuration of endocardial swellings in the outflow portion of the heart are compatible with the general architecture of full-grown examples of the anomaly. This configuration differs considerably from normal embryonic anatomy, but is still supported by the architecture of the myoepicardial mantle. It is concluded that endocardial swellings play a secondary role in the determination of fullgrown cardiac anatomy.

Embryo, Mammalian↗
PubMed1979

The value of diagnostic ultrasound as a screening test for intrauterine growth retardation: comparison of nine parameters.

In an attempt to devise a screening method for the detection of unsuspected IUGR, a battery of ultrasonic measurements of the fetus were performed in a series of 255 patients at approximately 32, 34, and 36 weeks. The results obtained from the 16 growth-retarded and the 239 normally grown babies were evaluated. While no single measurement was found to discriminate the two groups, a simple combination of crown-rump length times area of trunk allowed us to identify an at-risk group comprising 11 per cent of the population. The false positive and false negative results were acceptable at levels of 10 and 6 per cent, approximately. It is considered that these results would justify a larger and prospectively randomized controlled trial to assess the benefits and drawbacks of applying these measurements in a screening schedule.

False Negative Reactions↗
PubMed1978

Gray scale ultrasound for the investigation of early pregnancy.

73 early gestations (6-14 wk) were investigated with gray scale ultrasound. 7 of them ended in spontaneous first-trimester abortion, and in all of these the findings were characteristic for spontaneous interruption of pregnancy. The remaining 66 continued to term. Regression analysis was performed with respect to the diameter of the gestation sac, the fetal crown-rump length, and the placental surface and thickness. The method is considered appropriate for the diagnosis of early abortion and the study of placental morphology and morphometry. On the basis of the results obtained with gray scale techniques, various concepts derived from B-scan observations (e.g. implantation locus and early twin observation) will have to be corrected.

Abortion, Spontaneous↗
PubMed1979

Effect of the chronic administration of nitrous oxide 0.5% to gravid rats.

Twenty-four gravid Wistar rats (12 experimental and 12 control) were studied. From day 1 to day 19 of gestation the experimental group was exposed day and night to nitrous oxide 0.5%, while the control group was exposed to air. On day 19 the rats were killed and a detailed examination of the uterus, ovaries and fetuses was undertaken. The fetuses were fixed, cleared and stained with alizarin red, examined for skeletal anomalies and their crown-rump lengths measured. There was a significant decrease in litter size of the dams exposed to nitrous oxide as compared with control (P less than 0.001). Fetal resorption occurred in 10 of the 12 exposed dams. Skeletal anomalies were observed in 9% of the fetuses in the experimental group and there was an overall reduction in their size. None of the above changes were observed in the control.

Abnormalities, Drug-Induced↗
PubMed1979

The effects of maternal ethanol consumption in the rat on the development of their offspring.

The effects of ethanol on the physical development and maturation of the CNS in the offspring of lactating rats were investigated. Dams were fed: 1) regular stock diet (control), 2) liquid diet containing 35% of the calories as ethanol (ETOH) or 3) liquid diet with maltose-dextrin substituted for the calories supplied by ethanol (isoenergetic = IE). Diets were administered from the 14th day of gestation until 3 weeks post-partum (pre- and post-natal exposure) or from birth until 3 weeks post-partum (post-natal exposure). Body weight, crown-rump length and tail length, as well as brain weight were followed longitudinally in the pups. The growth in the pups of dams fed ETOH diet and those fed IE diet were significantly less than that observed in the pups of control dams. Furthermore, pups of dams fed the ETOH diet showed retardation in growth indices and brain weight at various ages when compared to pups of equivalent age from dams fed the IE diet. Therefore, administration of ethanol to pregnant or lactating dams impaired the physical growth, including central nervous systems (CNS), of their offspring more than those changes caused by nitritional deprivation.

Animals↗
PubMed1978

Histochemical and radiologic studies of the human fetal mandibular condyle.

Histochemical investigations on the mandibular condyle were performed on 72 human embryos and fetuses of crown-rump lengths (CRL) ranging from 26 to 186 mm, representing skeletal maturity indices expressed in CNO values (CNO = composite number of ossified bones in the hand and foot) ranging from 0-0 to 19-12. The development of the mandibular condyle is described according to morphology and to histochemical reactions for glycosaminoglucuronglycans, collagen, glycogen, alkaline and acid phosphatase, and nonspecific AS esterase. The development is described for (1) the bony component of the mandibular condyle, (2) the condylar cartilage, and (3) the fibrous cover of the mandibular condyle. For each tissue component, maturation steps are set up and included in the total evaluation of the condylar maturity stages. The developmental sequence set up on the basis of the morphologic and histochemical findings was followed by all condyles investigated. From this it may be presumed that the developmental sequence in human mandibular condylar components is constant during the former half of the prenatal period. The material available did not justify a description of skeletal development in the mandibular condyle as a function of fetal size, CRL, or skeletal maturity in the hand and foot.

Alkaline Phosphatase↗
PubMed1977

Pineal serotonin metabolism in non-innervated perinatal glands before and after intraocular maturation: supersensitivity of adrenoceptors that have never been innervated.

Transplantations were made of fetal pineal glands (crown-rump length, CRL, 19-30 mm) or pineal glands from adult male rats to the anterior chamber of the eye of the rat. Studies were performed with regard to the importance of the age of the donor animal (and thereby the degree of maturation and innervation of the gland to be transplanted) for the possible development of denervation supersensitivity. The transplants were cultured in a medium containing 14C-serotonin. Increased production of 14C-N-acetylserotonin (NAcS) was used as the main criterion for beta-adrenergic stimulation. 4 experimental groups were obtained by transplanting fetal or adult pineals to intact or sympathetically denervated eyes. In all 4 groups beta1-stimulation (KWD 2033 10(-6) M) increased 14C-NAcS formation. The response to beta-stimulation was significantly higher in denervated fetal pineal transplants than in innervated fetal transplants and thus demonstrating beta-receptor supersensitivity. It was concluded that a) the ability to respond to beta-adrenoreceptor stimulation with increased 14C-NAcS formation develops between the 18th and 20th day of gestation, b) transplants derived from fetal as well as from adult rats can respond to beta-adrenergic stimulation, c) this sensitivity also develops in oculo in transplants that at the time of transplantation lacked the capacity to increase their 14C-NAcS formation in response to treatment with beta-agonist, d) denervation supersensitivity occurs in fetal transplants that became mature in sympathetically denervated eyes.

Animals↗
PubMed1978

Embryotoxic effects of polybrominated biphenyls (PBB) in rats.

Pregnant Sprague Dawley rats were given 0, 0.25, 0.5, 1, 5, and 10 mg of a commercial polybrominated biphenyl, FireMaster BP-6 (PBB), in olive oil by gavage each day from days 7 through 15 of pregnancy. Laboratory chow and water were given ad libitum. Treatment with PBB had no significant effect on body weight gain, food and water consumption, and urine production. The mothers were killed on day 20, and the only significant effect observed was an increased liver weight of those given 1, 5, and 10 mg PBB. Spleen, kidney, ovarian, gravid uterine, and perirenal fat pad weights were similar to those of control mothers. PBB had no significant effect on number of live/dead fetuses, crown-rump length or fetal weight. No grossly malformed fetuses were observed in PBB-treated mothers. The effects of PBB transfer from mothers to nursing pups was studied by reciprocal exchange of pups between control mothers and mothers treated with 10 mg PBB. When the pups were 21 days old, they were weaned and fed control chow. The following four combinations of prenatal-postnatal exposure were studied: control-control (C:C); control-PBB (C:PBB); PBB-control (PBB:C); and PBB-PBB. Although the birth weights of pups from PBB-treated mothers were similar to those of the controls, body weights of 60-day-old males exposed prenatally and postnatally (PBB:C, C:PBB, and PBB:PBB) were less (p less than 0.05) than those of the controls (C:C). The weights of the perirenal fat pads of male and female pups exposed to PBB were less (p less than 0.05) than the control. Liver weights, on a body weight basis, were higher in male and female pups exposed to PBB. Vaginal openings were delayed; the percentages of 36-day-old pups with open vaginas were 50 (C:C), 38 (PBB:C), 28 (C:PBB), and 30 (PBB:PBB).

Animals↗
PubMed1979

The growth and development of the squirrel monkey (Saimiri Sciureus).

Squirrel monkeys of 2 subspecies, Bolivian and Colombian, were removed from their mothers on the day of birth and nursery reared for up to 2 years of age. Infants were tested weekly for 12 weeks, then monthly for 1 year, and at 2 years of age. Tests included morphology (body weight, crown-rump length, and head measurements), behavior (reflexes, activity, reaction to the surrogate), and physiology (heart rate, respiratory rate, temperature and optokinetic nystagmus). Data show some likenesses and some differences between the 2 subspecies.

Animals↗
PubMed1978

Histological development of stapes footplate in human embryos.

Normal development of the human stapes footplate was investigated in serial sections by light microscopy. Materials were obtained from 35 Japanese embryos from the 6th to 32nd week of embryonal age. Eighteen embryos up to 16 weeks of age (3.5mm to 105mm in crown-rump length) were examined, focusing particularly on the lamina stapedialis of the otic capsule. The present study showed that primordial formation of the lamina stapedialis appeared in 16mm embryo and that the lamina was completely formed and fused to the base of the annular stapes in a 35mm embryo. In a 50mm embryo, the adult form of stapes was found with a rim and annular ligament. The results, therefore, seemed to essentially agree with the theory of dual origin and development of the footplate proposed by Cauldwell and Anson, and teratogenic agents might affect any stage of the process producing anomalies, including congenital footplate fixation, congenital absence of the oval window and calcification of the annular ligament.

Ear Ossicles↗
PubMed1978

Peptidergic (VIP) innervation of the esophagus.

Nerves displaying vasoactive intestinal polypeptide (VIP) immunoreactivity were demonstrated in the esophagus of rats, cats, and pigs. Furthermore, electron microscopy revealed the presence of nerve terminals displaying the features of peptidergic nerves. VIP nerves were abundant within the smooth muscle layer of the lower esophagus of cat and pig. Immunoreactive nerve fibers and nerve cell bodies were found in the plexuses of the esophageal wall. In pig fetuses VIP immunoreactive nerve cell bodies were observed already at crown-rump length of 4 cm. VIP nerves were also observed in human fetal esophagus. For recording of the motor effects of VIP, segments were taken from cat esophagus close to the esophagogastric junction. VIP induced a dose-dependent relaxation upon contraction by carbamylcholine.

Animals↗
PubMed1979

Changes in axonal numbers in developing human trochlear nerve.

Complete axonal counts have been made in the intracranial parts of trochlear nerves from human fetuses of 9.2, 10 and 24 cm crown-rump length. A count was also made in the intraorbital part of the nerve from the 10 cm specimen. Schwann cell nuclei were also counted in typical cross sections, but do not necessarily reflect very accurately the schwann cell contents of the nerves. Axonal numbers conform to the propositions (1) that they do not all grow out at once, (2) do not all survive and (3) that degeneration may occur before or after myelination has begun. It seems inevitable that some loss of Schwann cells occurs in relation to the degeneration of myelinated axons, but there is no evidence for or against such a loss in relation to the degeneration of unmyelinated axons. Overall, however, Schwann cell numbers tend to increase as the number of myelinated axons increases.

Axons↗
PubMed1979

Muscular development of the bladder neck in the human fetus.

We conducted a histologic study of the muscular development of the bladder neck in human fetuses of 5 to 23 cm crown-rump length (CRL) and in neonates in special reference to the middle circular layer of the posterior wall of the bladder neck (posterior circular muscle of the bladder neck) and the deep trigonal muscle. Our attempt was to determine the anatomic relationship between and the origins of the two musculatures. The posterior circular muscle had begun to differentiate in the fetus of 8.3 cm CRL in which the trigonal musculature was indistinguishable. Differentiation of the deep trigonal musculature was evident in the fetus of 17 cm CRL; a complete growth in which the muscle was connected to the posterior circular muscle of the bladder neck was evident only in the largest fetus (23 cm CRL). We conclude that the deep trigonal muscle and the posterior circular muscle of the bladder neck are of different origins.

Gestational Age↗
PubMed1976

Milk protein quantity and quality in low-birthweight infants: I. Metabolic responses and effects on growth.

The optimal quantity and quality of protein for low-birthweight infants is undefined. In this study, 106 well, appropriate-for-gestational age, low-birthweight infants weighing 2,100 gm or less were grouped in three gestational age categories: T1 = 28 to 30 weeks; T2 = 31 to 33 weeks; T3 = 34 to 36 weeks. Each group was assigned randomly to either banked human milk (BM) or to one of four isocaloric formulas varying in quantity and quality of protein but not in mineral content or in fat content: formula 1 = 1.5 gm of protein per 100 ml, 60 parts bovine whey proteins to 40 parts bovine caseins; formula 2 = 3.0 gm of protein per 100 ml, 60:40; formula 3 = 1.5 gm of protein per 100 ml, 18:82; formula 4 = 3.0 gm of protein per 100 ml, 18:82. Caloric intake was 117 kcal/150 ml/kg/day for the formulas. Human milk was fed at 170 ml/kg/day in order to attain a caloric intake approximately equal to that of the formulas. No significant differences were found in the rate of growth in crown-rump length, in femoral length, in head circumference, or in rate of gain in weight from time of regaining birthweight to time of discharge at 2,400 gm. Blood urea nitrogen, urine osmolarity, total serum protein, serum albumin, and serum globulin varied directly with the quantity of protein in the diet: F2, F4 greater than F1, F3 greater than BM. Blood ammonia concentration varied with both quantity and quality of protein in the diet: F2, F3, F4 greater than F1, BM. Metabolic acidosis was more frequent, more severe, and more prolonged in the infants fed the casein-predominant formulas (F3,F4) than in those fed the whey protein-predominant formulas (F1, F2).

Ammonia↗
PubMed1978

Electron microscopy of the early embryonic development of the human corneal epithelium.

The eyes of a human embryo in the 6th week, 11 mm crown-rump (C.R.) length, and of a human embryo in the 7th week, 19 mm C.R. length, were examined. In the embryo of 11 mm C.R. length, the lens vesicle had just detached from the surface ectoderm, the presumptive corneal epithelium. The acellular primary corneal stroma appeared between the lens vesicle and the overlying ectoderm. The fine structure of the ectodermal cells, of their basal lamina, and of the primary stroma is described. In the embryo of 19 mm C.R. length, mesenchymal cells had moved from the periphery into the space between the ectoderm and the lens. There were remarkable changes in the structure of the corneal epithelial cells, in their basal lamina, and in the underlying substances of the primary stroma.

Cornea↗