PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Fetal Development”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 307 records · Page 17Linked to original sources
PubMed2002

Behavioral perinatology: biobehavioral processes in human fetal development.

Behavioral perinatology is as an interdisciplinary area of research that involves conceptualization of theoretical models and conduct of empirical studies of the dynamic time-, place-, and context-dependent interplay between biological and behavioral processes in fetal, neonatal, and infant life using an epigenetic framework of development. The biobehavioral processes of particular interest to our research group relate to the effects of maternal pre- and perinatal stress and maternal-placental-fetal stress physiology. We propose that behavioral perinatology research may have important implications for a better understanding of the processes that underlie or contribute to the risk of three sets of outcomes: prematurity, adverse neurodevelopment, and chronic degenerative diseases in adulthood. Based on our understanding of the ontogeny of human fetal development and the physiology of pregnancy and fetal development, we have articulated a neurobiological model of pre- and perinatal stress. Our model proposes that chronic maternal stress may exert a significant influence on fetal developmental outcomes. Maternal stress may act via one or more of three major physiological pathways: neuroendocrine, immune/inflammatory, and vascular. We further suggest that placental corticotropin-releasing hormone (CRH) may play a central role in coordinating the effects of endocrine, immune/inflammatory, and vascular processes on fetal developmental outcomes. Finally, we hypothesize that the effects of maternal stress are modulated by the nature, duration, and timing of occurrence of stress during gestation. In this paper, we elaborate on the conceptual and empirical basis for this model, highlight some relevant issues and questions, and make recommendations for future research in this area.

Behavior↗
PubMed1986

The effects of Love Canal soil extracts on maternal health and fetal development in rats.

The effects of a solvent extract of the surface soil of the Love Canal chemical dump site, Niagara Falls, New York, and of a natural extract, or leachate, which is drained from the canal for treatment, on the maternal health and fetal development were determined in rats. The solvent extract, which was contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (2, 3,7,8-TCDD) at 170 ppb and numerous other chlorinated organic compounds with the primary identified components being the isomers of benzenehexachloride (BHC), was dissolved in corn oil and administered by gavage to pregnant rats at 0,25,75, or 150 mg crude extract/kg/day on Days 6-15 of gestation. A 67% mortality was observed at the highest dose. The rats were sacrificed on Day 20. Dose-related increases in relative liver weight accompanied by hepatocyte hypertrophy were observed at all dose levels. Fetal birthweight was decreased at 75 and 150 mg extract/kg/day. No major treatment-related soft tissue or skeletal malformations, except for delayed ossification, were observed. Based on literature values for BHC, all of the observed toxicity could be accounted for by the BHC contaminants of the extract. The crude organic phase of the leachate was administered to pregnant rats at 0,10,100, or 250 mg/kg/day as described above. Maternal weight gain decreased at 100 and 250 mg/kg/day, accompanied by 5 and 14% maternal mortality, and 1 and 3 dead fetuses, respectively. Early resorptions and the percentage of dead implants increased whereas fetal birthweights were decreased at 250 mg/kg/day. No major treatment-related soft tissue or skeletal malformations, except for delayed ossification, were observed. The primary components of the complex leachate by mass were tetrachloroethanes; however, 2,3,7,8-TCDD, which was present at 3 ppm, probably accounted for all the observed toxicity.

Abnormalities, Drug-Induced↗
PubMed1983

Fetal development: effects of decompression sickness and treatment.

Pregnant hamsters were exposed to 7.1 ATA (200 fsw) of compressed air breathing for 40 min. Comparisons were made between three groups of pregnant hamsters: (a) those that developed decompression sickness (DCS); (b) those that did not; and (c) a control (non-divided) group. As reported previously, maternal DCS if untreated resulted in frequent and severe teratogenic effects. Furthermore, fetuses from those females who apparently did not develop DCS were significantly smaller at term than fetuses from the control animals. However, fetuses from females that were treated for DCS did not differ from controls. This suggests that 40-min, 200-fsw dives per se are detrimental to fetal development in hamsters.

Animals↗
PubMed2002

Expression of CD21 and CD23 during human fetal development.

Neonates produce lower levels of IgE compared with adults. Diminished IL-4 production and impaired up-regulation of CD40L by neonatal T cells could explain this, however other regulators of IgE production, such as CD21 and CD23, could contribute to reduced circulating IgE levels during fetal development. Heparinized blood samples were collected from adults and from the umbilical cord at premature and term births. Whole blood flow cytometry was used to assess the percentage of T (CD3(+)) and B (CD19(+)) lymphocytes expressing CD21 and/or CD23 at 26-29 (n = 3), 30-33 (n = 7), 34-37 (n = 5), and >37 (n = 11) wk of gestation, as well as in adults (n = 15). Plasma-soluble CD21 was also measured. At term, the percentage of CD21(+) and CD23(+) B cells was comparable to the adult, however, the percentage of cells positive for each of these surface antigens was decreased significantly before term. The percentage of T cells expressing CD21 from all gestations was significantly higher than the adult and the percentage positive decreased with increasing gestational age. Conversely, soluble CD21 levels increased with increasing gestation to be comparable to the adult by term. Thus, it is unlikely that altered expression of CD21 and CD23 on B cells contributes to the low level of IgE in the neonatal circulation unless functional differences occur or a lack of processing to the soluble form is important in regulating IgE production. However the abundance of CD21-positive T cells could alter the T- and B-cell interaction necessary for IgE switching by B cells and, thereby, especially with impaired IL-4 production, limit IgE production.

Antigens, CD19↗
PubMed1981

[Effect of ethanol on ovulation, reproduction and fetal development in the rat].

Single doses of ethanol (0.5 and 4 g/kg) were injected at 18 h of the diestrus, 9 h of the proestrus and 18 h of the estrus phase (first day of pregnancy). The ovarian cycle number of ovules and ovarian follicles, insemination, number of embryos, fetal development and the observed malformation were evaluated. Alcohol (4 g/kg) at 18 h of the diestrus, increased the receptive estrus phase and the number of mature follicles in the ovary, while it decreased the number of ovulations, pregnancies and embryos in rats. It was found that alcohol (4 g/kg) at preovulatory periods, increased the percentage of dead and malformed fetuses, and decreased the length of the higher limbs. Furthermore, the same doses of alcohol administered at the first day of pregnancy, produced a decrease in weight, size and length of the legs. Results showed that single doses of alcohol injected in preovulatory periods and first day of pregnancy, had a teratogenic action. Furthermore, alcohol inhibited ovulation and stimulated animal receptibility when administered at 18 h of diestrus.

Abnormalities, Drug-Induced↗
PubMed1977

Quantitative histochemistry of the spinal motor neurone nucleus during human fetal development.

A quantitative histochemical study of the developing anterior horn cell nucleus was undertaken. The DNA, the arginine and lysine-rich histones as well as the acidic nuclear proteins of the spinal motor neurone nucleus were estimated during normal fetal development by means of scanning microdensitometry. The arginine-rich histones and the acidic nuclear proteins were found to be increased at the 12-14 week period, a finding which suggests that this period is critical in the differentiation of the spinal motor neurone.

Arginine↗
PubMed1992

Ultrasound studies of the effects of certain poisonous plants on uterine function and fetal development in livestock.

Ingestion of locoweed (Astragalus spp. and Oxytropis spp.) by pregnant livestock may result in fetal malformations, delayed placentation, reduced placental and uterine vascular development, hydrops amnii, hydrops allantois, abnormal cotyledonary development, interruption of fetal fluid balance, and abortion. Ultrasonography of pregnant sheep fed locoweed demonstrated that abortion was first preceded by changes in fetal heart rate and strength of contraction and structural changes of the cotyledons, followed by increased accumulation of fetal fluid within the placental membranes and death of the fetus. During pregnancy the toxic agent in locoweed (swainsonine) apparently passes through the placental barrier to the fetus and during lactation through the milk to the neonate. Poison-hemlock (Conium maculatum), wild tree tobacco (Nicotiana glauca), and lunara lupine (Lupinus formosus) all contain piperidine alkaloids and induce fetal malformations, including multiple congenital contractures and cleft palate in livestock. Ultrasonography studies of pregnant sheep and goats gavaged with these plants during 30 to 60 d of gestation suggests that the primary cause of multiple congenital contractures and cleft palate is the degree and the duration of the alkaloid-induced fetal immobilization.

Animals↗
PubMed1987

[Effects of overall food restriction on embryo-fetal development in the rat].

The effects of different levels of food restriction on the fetal-embryo development have been tested in rats (Sprague Dawley) weighing 250 g. Experimental groups received 100 (control), 75, 50 or 25% of mean daily consumed food containing 17% of proteins, either from the coupling (Day 1) or from the nestling (Day 6) and till the sacrifice (Day 21). The weight of the mothers and the fetus is diminished in function of the degree and the duration of the food restriction. The study of the maternal growth shows an adaptation to the food restriction as well as the pregnancy anabolism. The last one is not observed in the females presenting an early embryonic mortality. The nestling is not affected in any of the groups and the embryonic mortality is only observed at the highest restricted level in 1/10 female restricted from Day 6 on and in 5/10 of the rats restricted from Day 1 on. In these last ones, the emaciation between Day 1 and Day 21 after hysterectomy is 37% and the growth of the surviving fetuses is only 40% of the controls. Embryonic mortality most often precocious (before the 10th Day) shows a phenomenon of "all or none" and touches the entire litter of the females concerned; the others maintain a normal pregnancy. The fetal growth seems privileged as compared with the maternal growth. These restrictions have neither influenced the sex ratio, nor induced any specific teratogenic effect: the delayed ossification seems to be expressed precociously on the 5th sternebra.

Animal Nutritional Physiological Phenomena↗
PubMed1984

Expression of cellular oncogenes during embryonic and fetal development of the mouse.

Cellular oncogenes are conserved with great fidelity across a broad span of evolution. This avid conservation suggests possible roles in critical physiologic functions. Little, however, is known about their activity in normal cellular processes. In this study, we examined the expression pattern of eight cellular oncogenes during embryonic and fetal development of the mouse. Five of these genes (c-myc, c-erb, c-Ha-ras, c-src, and c-sis) were expressed at appreciable levels, and four were modulated in a consistent manner during the course of prenatal development.

Age Factors↗
PubMed1999

Intrauterine infusion of bacterial lipopolysaccharide (LPS) prior to mating has no adverse effect on fertility, fetal survival and fetal development.

Lipopolysaccharide (LPS, endotoxin) is a component of the cell wall of gram-negative bacteria and a potent inducer of severe inflammatory reactions. In mice, systemically administered LPS induces fetal resorption and increases fetal mortality. However, effects of intrauterine LPS on fertility, fetal survival and development have not been reported. In the present study, pigs were used to determine the effect of intrauterine infused LPS on fertility, fetal survival and development. Prior to mating, gilts received intrauterine infusion of either a single dose of saline or increasing doses of LPS in saline using an insemination catheter. On day 30 of pregnancy, gilts were hysterectomized and litter size, fetal length, number of corpora lutea (CL), ovarian and placental weights, and allantoic and amniotic fluid volumes were recorded. Blood progesterone levels from days 10-30 of pregnancy were also determined. Results indicated that intrauterine infusion of LPS had no adverse effects on blood progesterone levels, fertility, fetal survival or fetal development. Intrauterine injection of LPS did cause an increase in fetal weight and amniotic fluid volume (P < 0.05). These results suggest that sperm, oocytes and gametes are tolerant of local LPS challenge and, to some extent, this mechanism protects gametes and conceptuses from maternal response to mating introduced bacteria and their potential endotoxins.

Amniotic Fluid↗
PubMed2002

An oral (gavage) control embryo-fetal development study in the Wistar Hannover rat.

Many of the studies conducted to examine the developmental and reproductive toxicity potential of candidate pharmaceuticals use the Sprague-Dawley rat as the animal model. This is due in part to the large database for this outbred rat available for comparison of litter data, and the low incidence of fetal malformations and variations. The following study was conducted to generate information on potential embryo-fetal developmental defects and litter data in another outbred stock of rat, the Wistar Hannover. One hundred fifty pregnant female Wistar Hannover rats (Tac:Glx:WIfBR) were dosed orally once per day with distilled water from Gestation Days (GD) 6 through 17 covering the time from implantation to closure of the hard palate (GD0 = day of insemination). Caesarean sections were performed on Day 20 of gestation. All fetuses were examined for external, visceral and skeletal malformations and variations. Macroscopic and histomorphologic examinations were also completed for the F0 females at termination. The percent pregnant (88%) and litter size (average 10.6) were found to be lower than that commonly reported for the Sprague-Dawley rat (Crl:CD (SD)BR; 95.4% and 14.6, respectively). Pre-implantation loss (14.1%), post-implantation loss (7.4%) and percent resorptions (7.2%) occurred at a higher incidence than typically seen in the Sprague-Dawley rat (5.9, 5.6 and 5.1%, respectively). The average fetal body weights for both the female and male rats were lower than those typically seen in the Sprague-Dawley rat. External, visceral and skeletal examination of the F1 fetuses revealed numerous malformations and variations which also occurred at higher incidences than those reported for the Sprague-Dawley rat. Routine macroscopic and histomorphologic examination showed there were no changes that would be interpreted to have impaired mating performance, fertility or gestation. Thus, this study provides information on the reproductive effects and the background incidence of embryo-fetal development defects that could be used for comparison to those identified when using this outbred rat for developmental and reproductive toxicity studies, as well as for comparison to the more commonly used rat stock, the Sprague-Dawley rat. For the parameters evaluated, the Wistar Hannover rat had greater variability and an increased incidence of spontaneous malformations as compared to the Crl:CD (SD)BR Sprague-Dawley rat. These findings should be considered if this stock of rat is selected in the conduct of developmental and reproductive toxicity studies.

Administration, Oral↗
PubMed1984

The effect of very prolonged membrane rupture on fetal development.

This retrospective study examined the effects of very prolonged membrane rupture of more than 1 week on the development of pulmonary hypoplasia and positional deformities in the infants of 100 consecutive women. A control group of infants who were matched for gestational age at delivery, sex, and time of delivery was identified. The results indicate that there was a statistically significant difference (p less than 0.001) in the occurrence of pulmonary hypoplasia and positional deformities. The greatest impact of prolonged membrane rupture on fetal development was seen in the patients in whom membrane rupture occurred prior to 26 weeks' gestation and the duration of rupture was more than 5 weeks.

Bone and Bones↗
PubMed1975

Fetuin, an inhibitor of lymphocyte transformation. The interaction of fetuin with phytomitogens and a possible role for fetuin in fetal development.

Fetuin, the bovine alpha-fetoprotein, contains glycopeptide sequences similar to those found on red cells. As a result, it is capable of strong physical interaction with the phytohemagglutinin isomitogens (H-PHAP) which possess two or more R (red cell binding) subunits as part of their tetrameric structures. Fetuin shows little or no interaction with L-PHAP, a phytohemagglutinin made up of four L subunits which also lack red cell affinity. Despite these differences fetuin is able to inhibit both H- and L-PHAP-induced lymphocyte transformation and is also capable of inhibiting the mitogenic effects of pokeweed mitogen, concanavalin A, antithymocyte antiserum, and the one-way mixed lymphocyte culture. In the case of L-PHAP, the inhibitory effect of fetuin is proportional to the intensity of the mitogenic stimulus. The inhibitory effects of fetuin upon lymphocyte transformation may result from perturbation or "blindfolding" of the cell membrane in a manner analogous to other immunosuppressive serum alpha-globulins. Alpha-Fetoproteins may play an immunoregulatory role during fetal development.

Alpha-Globulins↗
PubMed1990

[Echographic dynamic control of the urinary system and fetal development in pregnant women with acute pyelonephritis].

Ultrasonography in 52 pregnant women with acute pyelonephritis has been found to be a useful marker of efficacy of aggressive care. Reversal of inflammation in acute pyelonephritis without an associated disease reduced the kidney size and restored urine flow by the end of the 7-9th day of therapy. In pyelonephritis coexisting with nephrolithiasis, reversal of inflammation did not completely restore urine flow until a stone in the urinary tract was passed or surgically removed. The clinical patterns of pyelonephritis were elucidated in congenital renal malformations. The urine flow was completely restored and kidney sizes were maximally contracted postpartum. With an early therapy, the fetal development was appropriate for gestational age. Frequently relapsing pyelonephritis concomitant with toxemia or severe congenital renal disease led to intrauterine growth retardation.

Acute Disease↗