Gestation Period (gestation + period)

Distribution by Scientific Domains
Distribution within Life Sciences


Selected Abstracts


Combined repeated dose and reproductive/developmental toxicity screening test of the nitrophenolic herbicide dinoseb, 2- sec -butyl-4,6-dinitrophenol, in rats

ENVIRONMENTAL TOXICOLOGY, Issue 2 2008
Mariko Matsumoto
Abstract In a combined repeated dose toxicity study with reproduction/developmental toxicity screening test, Crj:CD(SD)IGS rats were dosed with dinoseb, 2- sec -butyl-4,6-dinitrophenol, by gavage at 0 (vehicle), 0.78, 2.33, or 7.0 mg/kg bw/day. Six males per group were dosed for a total of 42 days beginning 14 days before mating. Twelve females per group were dosed for a total of 44,48 days beginning 14 days before mating to day 6 of lactation throughout the mating and gestation period. Recovery groups of six males per group and nonpregnant six females per group were dosed for 42 days followed by a 14-day recovery period. No deaths were observed in males of any dose group or in females of the recovery groups. At 7.0 mg/kg bw/day, eight females died and two animals were moribund during late pregnancy, and a significant decrease in body weight gain was found in both sexes. Hematocrit was significantly higher at 0.78 mg/kg bw/day and above in the main group males at the end of administration period. Reduction in extramedullary hematopoiesis in the spleen was significant at 2.33 mg/kg bw/day in the main group females. Sperm analysis revealed a decrease in sperm motility and an increase in the rates of abnormal sperm, abnormal tail, and abnormal head at 7.0 mg/kg bw/day. A number of dams delivered their pups and of dams with live pups at delivery was significantly lowered in the 7.0 mg/kg bw/day group. Based on these findings, the LOAEL for males and NOAEL for females were 0.78 mg/kg bw/day, and the NOAEL for reproductive/developmental toxicity was considered to be 2.33 mg/kg bw/day. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2008. [source]


Dietary exposure of mink (Mustela vison) to fish from the Housatonic River, Berkshire County, Massachusetts, USA: Effects on reproduction, kit growth, and survival

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2006
Steven J. Bursian
Abstract We evaluated the effects of feeding farm-raised mink (Mustela vison) diets containing polychlorinated biphenyl (PCB)-contaminated fish from the Housatonic River (HR; Berkshire County, MA, USA) on adult reproductive performance and kit growth and survival. Diets contained 0.22,3.54% HR fish, providing 0.34,3.7 ,g total PCBs (TPCB)/g feed wet wt (3.5,68.5 pg toxic equivalence [TEQ]/g). Female mink were fed diets before breeding through weaning of kits. Twelve kits from each treatment were maintained on their respective diets for an additional 180 d. Dietary PCBs had no effect on the number of offspring produced, gestation period, or other measures of adult reproductive performance. Mink kits exposed to 3.7 ,g TPCB/g feed (68.5 pg TEQ/g) in utero and during lactation had reduced survivability between three and six weeks of age. The lethal concentrations to 10 and 20% of the population (LC10 and LC20, respectively) were estimated to be 0.231 and 0.984 ,g TPCB/g feed, respectively. Because inclusion of PCB-contaminated fish that composed approximately 1% of the diet would reduce mink kit survival by 20% or more, it is likely that consumption of up to 30-fold that quantity of HR fish, as could be expected for wild mink, would have an adverse effect on wild mink populations. [source]


Evolution of a novel function: nutritive milk in the viviparous cockroach, Diploptera punctata

EVOLUTION AND DEVELOPMENT, Issue 2 2004
Anna Williford
Summary Cockroach species show different degrees of maternal contribution to the developing offspring. In this study, we identify a multigene family that encodes water-soluble proteins that are a major component of nutritive "Milk" in the cockroach, Diploptera punctata. This gene family is associated with the evolution of a new trait, viviparity, in which the offspring receive nutrition during the gestation period. Twenty-five distinct Milk complementary DNAs were cloned and partially characterized. These complementary DNAs encode 22 distinct Milk peptides, each of length 171 amino acids, including a 16-amino acid signal peptide sequence. Southern blot analysis confirms the presence of multiple copies of Milk genes in D. punctata. Northern analysis indicates tissue- and stage-specific Milk gene expression. Examination of the deduced amino acid sequences identifies the presence of structurally conserved regions diagnostic of the lipocalin protein family. The shared exon/intron structure of one of the Milk loci with lipocalin genes further supports a close evolutionary relationship between these sequences. [source]


Embryo growth rates in birds and mammals

FUNCTIONAL ECOLOGY, Issue 3 2010
Robert E. Ricklefs
Summary 1.,Embryo mass growth curves of 36 species of bird and 18 species of mammal were fitted by sigmoidal Gompertz functions, in which k (days,1) describes the rate at which the embryo approaches an asymptotic mass A (g). 2.,The parameters of the Gompertz function were uncorrelated with parameters of power functions fitted to the same growth data, indicating that the two models describe different aspects of growth. 3.,Asymptotes of the Gompertz functions for embryonic growth averaged 2·5 times neonate size, but were well below adult mass. Thus, the pre- and postnatal phases of growth are distinct and have different target sizes. 4.,Embryo growth rate (k) decreases as the ,1/4 power of neonate size; values for mammals were 63% of those of birds, on average. 5.,Embryo growth rate can be predicted solely by the length of the incubation or gestation period, regardless of the size of the neonate, with the same relationship for birds and mammals. 6.,Postnatal growth rate (kG) scales linearly with embryonic growth rate (k), but is nearly five- times more rapid, on average, in birds than in mammals. kG and k have similar magnitude in birds, but kG is relatively much slower than k in mammals. 7.,Rate of actuarial senescence , (year,1), measured by the increase in mortality rate with age, is positively related to the rate of embryo growth in both birds and mammals, but is higher in the latter. Moreover, rate of ageing in birds is uniquely related to embryo growth while that in mammals is uniquely related to postnatal growth rate. Thus, development and ageing appear to be differently connected in birds and mammals, although the basis for these relationships is not known. [source]


Do placental species abort offspring?

FUNCTIONAL ECOLOGY, Issue 2 2008
DeAngelis model, Testing an assumption of the Trexler
Summary 1We investigate how resource level affects reproduction in matrotrophic (Poeciliopsis prolifica) and lecithotrophic (P. monacha) fishes. 2One of our goals was to test an assumption of the Trexler,DeAngelis model for the evolution of matrotrophy, which was that matrotrophic species can adjust litter size by aborting offspring in low food conditions. Our more general goal was to elucidate other differences between the reproductive modes. 3Both species have superfetation and c. 30-day development time. Females of each species were assigned to high or low food availability for 30 days, or one gestation period. Any young born during that time interval would have initiated development before the initiation of the experiment. If embryos are aborted, then this would be seen as a reduction in brood size in the low food treatment relative to the high food treatment within this period. 4Our results suggest P. monacha responds to low food by sacrificing reproduction to maintain lipids, while P. prolifica maintains reproduction at the expense of lipids. Neither species showed a significant reduction in offspring number over the course of the experiment, suggesting that these species do not abort offspring in low food conditions. [source]


Three-dimensional sonographic evaluation of the fetal lumbar spinal canal

JOURNAL OF ANATOMY, Issue 5 2002
Thomas Wallny
Abstract In a prospective cross-sectional ultrasound study the size of the fetal lumbar spinal canal was evaluated to determine reference values for the lumbar part of the vertebral canal. One hundred and sixty-seven pregnant women undergoing routine obstetric ultrasound were studied between 16 and 41 weeks of gestation. Exclusion criteria consisted of structural fetal anomalies or growth restriction. Area and volume of the vertebral canal at L1, L3 and L5 were calculated by three-dimensional (3D) ultrasound. Length of the lumbar spine was also determined. The size of the spinal canal and spinal length correlated well with gestational age. No gestational-age-dependent differences in area and volume measurements between upper and lower lumbar spine were found. The results provide an in vivo assessment of the spinal canal by 3D ultrasound over the entire gestation period. [source]


Influence of different phosphorus levels and phytase supplementation in gestation diets on sow performance

JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 7-8 2007
K. Lyberg
Summary A total of 104 sows of different parities were studied. They were fed four diets with different phosphorus (P) levels during gestation for two reproductive cycles, while the same diet was fed during lactation. The aim was to decrease the total P level in the diet during gestation and to evaluate the effect on sow performance. The gestation treatments were low P (LP,; 3.7 g P/kg feed), low P with phytase (LP+, Ronozyme® P; 765 FTU/kg feed), medium P (MP; 4.5 g P/kg feed) and high P (HP; 6.0 g P/kg feed). Daily feed allowances were 2.6 kg during gestation and 9.2 kg during lactation. Number of born piglets and piglet mortality were higher (p < 0.05) in the LP treatments than in the MP and HP treatments. No difference (p > 0.05) in the numbers of live-born piglets, piglet birthweights, sow weights or piglet weight gains was found between the treatments. Phosphorus level in sow milk was the highest (p < 0.05) in the MP treatment, while no effects (p > 0.05) of treatment were found on milk Ca levels, P and Ca levels in serum of sows and piglets, nor on the analysed mineral, fat and protein contents of piglets. The estimated average requirement of P for the entire gestation period was 4.4,4.5 g/day. In conclusion, a reduction of dietary total P content during gestation did not result in negative effects on sow or piglet performance. This suggests that it should be possible to lower the dietary P content for gestating sows, compared with earlier recommendations, and thereby reduce the environmental P pollution. [source]


Neurobehavioral toxicity study of dibutyl phthalate on rats following in utero and lactational exposure

JOURNAL OF APPLIED TOXICOLOGY, Issue 7 2009
Yuanfeng Li
Abstract To investigate the neurobehavioral effects of dibutyl phthalate (DBP), an important endocrine disruptor known for reproductive toxicity, on rodent offspring following in utero and lactational exposure, pregnant Wistar rats were treated with DBP (0, 0.037, 0.111, 0.333 and 1% in the diet) from gestation day (GD) 6 to postnatal day (PND) 28, and selected developmental and neurobehavioral parameters of the offspring were measured. There were no significant effects of DBP on body weight gain of the dams during GD 6,20 or on the pups' ages of pinna detachment, incisor eruption or eye opening. Exposure to 1% DBP prolonged gestation period, decreased body weight in both male and female pups, depressed surface righting (PND 7) in male pups, shortened forepaw grip time (PND 10), enhanced spatial learning and reference memory (PND 35) in male pups. Exposure to 0.037% DBP also shortened forepaw grip time (PND 10), but inhibited spatial learning and reference memory in male pups. Sex × treatment effects were found in forepaw grip time (PND 10), spatial learning and reference memory, and the male pups appeared to be more susceptible than the females. However, all levels of DBP exposure did not significantly alter surface righting (PND 4), air righting (PND 16), negative geotaxis (PND 4 or 7), cliff avoidance (PND 7) or open field behavior (PND 28) in either sex. Overall, the dose level of DBP in the present study produced a few adverse effects on the neurobehavioral parameters, and it may alter cognitive abilities of the male rodent. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Therapeutic Strategies for Xenograft Rejection

JOURNAL OF CARDIAC SURGERY, Issue 5 2001
Ph.D., Shu S. Lin M.D.
ABSTRACT The increasing demand for transplantable organs over the past several decades has stimulated the idea of using animal organs in lieu of cadaveric organs in clinical transplantation. Pigs are now considered to be the most suitable source of organs for transplantation because of their abundant availability, their appropriate size, their relatively short gestation period, and the recent development in the technology to genetically manipulate them. In the past few years, some of the seemingly complex immunologic responses in pig-to-primate transplantation have been elucidated. This progress has allowed us to focus our efforts on devising specific therapeutic strategies to overcome or prevent some of the responses that contribute to rejection of the xenograft. In this article, we review the various approaches that might allow clinical xenotransplantation to come to fruition. [source]


Anticipation of Radiation Dose to the Conceptus from Occupational Exposure of Pregnant Staff During Fluoroscopically Guided Electrophysiological Procedures

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2005
JOHN DAMILAKIS Ph.D.
Introduction: A female employee working in the electrophysiology suite has the right to know potential radiation hazards to the unborn child before she is pregnant or before she decides to formally declare her pregnancy. Moreover, the employer of a declared pregnant worker must evaluate the work situation and ensure that the conceptus dose is kept below the maximum permissible level during the remaining gestation period. The aim of this study was to develop a method for conceptus dose anticipation and determination of maximum workload allowed for the pregnant employee who participates in fluoroscopically guided electrophysiological procedures. Methods and Results: A C-arm fluoroscopy system, an anthropomorphic phantom, and a radiation meter were used to obtain scattered air kerma dose rates separately for each of the three fluoroscopic projections typically used in the electrophysiology suite. Air kerma to conceptus dose conversion factors for all trimesters of gestation were calculated using Monte Carlo simulation. A formula is presented for the anticipation of the conceptus dose from occupational exposure of pregnant staff during fluoroscopically guided electrophysiological procedures. Normalized data are provided for conceptus dose estimation from occupational exposure of pregnant staff working in any electrophysiology laboratory. A methodology for estimation of maximum workload allowed for each month of the remaining gestation period of a worker who declared her pregnancy is proposed, which ensures that the regulatory dose limits are not exceeded. Conclusion: Data presented may be used for the implementation of a radiation protection program designed for pregnant staff working in an electrophysiological suite. [source]


Quantitative analysis of messenger RNA expression of matrix metalloproteinases (MMP-2 and MMP-9), tissue inhibitor-2 of matrix metalloproteinases (TIMP-2), and steroidogenic enzymes in bovine placentomes during gestation and postpartum

MOLECULAR REPRODUCTION & DEVELOPMENT, Issue 7 2007
M. Takagi
Abstract The relationship between the mRNA expression of proteolytic and steroidogenic enzymes in bovine placentomes was examined. Caruncle and cotyledon tissues were collected every 6 hr after spontaneous parturition until the fetal membranes were released. Based on the time of fetal membrane release after parturition, the specimens were classified as follows: (1) the early group, in which the fetal membranes were released within 6 hr after parturition; and (2) the late group, in which the fetal membranes were released 6,12 hr after parturition. The placentomes from a slaughterhouse were additionally collected as samples for the examination of enzymes during the gestation period. The mRNA expression of steroidogenic enzymes in the cotyledon was observed to be higher than that in caruncle tissues; however, the mRNA expression patterns of P450scc and StAR tended to be similar in both placental tissues. On the other hand, although the expression levels of TIMP-2 mRNA in both caruncle and cotyledon tissues were similar, during gestation and postpartum the expression levels of MMP-2 and MMP-9 mRNA were approximately 10 times higher in caruncle than in cotyledon tissue. Marked contrasting changes in mRNA expression patterns between pre- and postpartum periods were observed for MMP-2 and MMP-9 in caruncle tissues and for MMP-9 and TIMP-2 in cotyledon tissues. The present study provides the first evidence that MMP-2, MMP-9, and TIMP-2 mRNAs are expressed in bovine placentomes during the gestational and postpartum periods and suggests that these enzymes, in conjunction with steriodogenic enzymes, mediate fetal membrane detachment after parturition. Mol. Reprod. Dev. 74: 801,807, 2007. © 2006 Wiley-Liss, Inc. [source]


The politics of action on AIDS: a case study of Uganda

PUBLIC ADMINISTRATION & DEVELOPMENT, Issue 1 2004
James Putzel
This article examines the political dimensions of Uganda's progress in bringing a generalised HIV/AIDS epidemic under control. The article documents the history of the political processes involved in Uganda's battle against HIV/AIDS and analyses the complexities of presidential action and the relation between action at the level of the state and that taken within societal organisations. By the mid-1980s, Uganda was experiencing a full-blown epidemic, the virulence of which was connected with social dislocation and insecurity related to economic crisis and war. Political authorities faced the same challenge as other regimes experiencing the onslaught of AIDS in Africa. The epidemiological characteristics of HIV and AIDS,transmission through heterosexual activities, with a long gestation period, affecting people in the prime of their productive life,meant that action required wide-reaching changes in sexual behaviour, and the educational activities to achieve this, as well as relatively complex systems to monitor the virus and control medical practices (blood supplies, injection practices, mitigating drug delivery). The centralist character of the Museveni regime was crucial not only to mobilising state organisations and foreign aid resources, but also to ensuring significant involvement from non-state associations and religious authorities. The Ugandan experience demonstrates that there is a tension between the requirements for systematic action that a strong public authority can deliver and the need to disseminate information requiring a degree of democratic openness. The President was able to forge a coalition behind an HIV/AIDS campaign in part because the virus largely ignored the privileges of wealth and political power. With the development of antiretroviral therapy and the access that the wealthy can gain to these drugs, this basis for the broadest possible coalition to fight HIV/AIDS may be weakened in the future. Copyright © 2004 John Wiley & Sons, Ltd. [source]


Genital swellings in silvered langurs: what do they indicate?

AMERICAN JOURNAL OF PRIMATOLOGY, Issue 5 2007
Nichole Shelmidine
Abstract The occurrence of genital swellings was examined in adult female silvered langurs (Trachypithecus cristatus). In contrast to the exaggerated swellings found in cercopithecines and apes, genital swellings in silvered langurs are confined to the vulva and the surrounding perineum, but they may nevertheless convey information similar to that of exaggerated swellings (i.e., correlate with the receptive period and fertility). If so, genital swellings would be expected to occur most frequently in cycling females, and sexual behavior and male interest should most frequently involve females with swellings. Swellings during gestation, if they occur at all, should be most pronounced at the beginning. Swelling sizes (in three size categories) in nine adult females were examined throughout different reproductive states (cycling, pregnant, and lactating), and in relation to proceptivity, receptivity, and attractivity. Data were collected from November 2002 through March 2004 (on 500 of the 502 calendar days) at the Wildlife Conservation Society's Bronx Zoo. Female sexual behavior (proceptivity and receptivity) and male inspection (attractivity) were recorded each day for 6,hr by video camera (2,948,hr total) and analyzed as present or absent for each female day. Swellings were assessed directly (not from videotapes). In contrast to the predictions, swellings occurred significantly less frequently in cycling females (compared to pregnant females) and no regular, cyclic pattern could be detected. Some females conceived without a swelling. Female attractivity was independent of swellings but coincided with proceptive behavior. Swellings occurred most frequently in pregnant females, especially toward the end of the gestation period. Therefore, genital swellings in silvered langurs are not similar to exaggerated swellings or the smaller genital swellings that have been described for some other primates. It is currently not clear what they signal to conspecifics. Male behavior needs to be studied in more detail, and the hormonal basis for these swellings should be explored. Am. J. Primatol. 69:519,532, 2007. © 2006 Wiley-Liss, Inc. [source]


Effects of Growth Hormone on Female Reproductive Organs

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2001
G. G. Kaiser
During the last decade many experiments have been performed to study the effects of growth hormone (GH, somatotropin) on reproductive functions. Most of the studies found only slight or no effects of GH treatment, both on the oestrous cycle and on gonadotropin, progesterone, or oestrogen serum levels. In GH-treated animals, elevated levels of insulin-like growth factor I and GH in the serum could be correlated with an increased number of small (<5 mm in diameter) ovarian follicles, possibly as a consequence of a reduction of apoptosis and follicular atresia. There is still controversy over the effects of GH on in vivo and in vitro embryo production and on the gestation period. Recent studies produced some evidence that GH-receptor is expressed in ovarian tissue, implying a direct role for GH in the ovary. [source]


Government Enterprises & Industrial Relations in Late Qing China

AUSTRALIAN JOURNAL OF POLITICS AND HISTORY, Issue 1 2001
David Pong
This study examines the development of labour organisation and industrial action among workers in government enterprises in the late Qing (1860-1912). Because these were the largest industrial enterprises using the most advanced machinery, one expects that the workers in them would play the leading role in labour organisation. Further, during the centuries-long gestation period, the period of embryonic capitalism, workers in traditional enterprises had already developed a tradition of industrial action. Yet this tradition of protest did not appear to have contributed much to labour activism in the modern government works. Quite the contrary, it was in private industries, whether Chinese- or foreign-owned, that we find a higher level of labour organisation and activism. This is an unexpected discovery, for which an explanation is attempted. [source]


Transcutaneous ultrasound over the right flank to diagnose mid- to late-pregnancy in the dairy cow

AUSTRALIAN VETERINARY JOURNAL, Issue 8 2009
JC Hunnam
Objective To investigate the practical application and image quality of transcutaneous ultrasonography across the right flank for the diagnosis of mid- to late-gestation in cattle. Procedure Dairy cows of known pregnancy status were used to establish criteria for the identification of mid- to late-stage pregnancy by transcutaneous ultrasonography. Factors involved in the practical application of transcutaneous ultrasound for routine use in pregnancy diagnosis in dairy cattle were also examined. Results Transcutaneous ultrasound, using a 3.5-MHz sector transducer applied over the caudodorsal right flank fold, allowed rapid and detailed visualisation of bovine pregnancy (i.e. fetus, fetal fluids, placentomes and/or fetal membranes) and could be used to establish criteria for the diagnosis of pregnancy. The commonly available cattle holding facilities of the herringbone dairy, rotary herringbone dairy, AI race or crush, and walk-through dairy all allow safe access to the right flank of a dairy or beef cow. However, transcutaneous scanning over the right flank is difficult in modern rotary turnstile dairies. Conclusion A 3.5-MHz sector transducer applied over the caudodorsal right flank fold allows detailed visualisation of the bovine fetus in most types of cattle-holding facilities. Further investigation of the sensitivity and specificity of this technique over the entire gestation period and its possible use in ageing of the bovine fetus is merited. [source]


Female-biased natal and breeding dispersal in an alpine lizard, Niveoscincus microlepidotus

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2003
MATS OLSSON
We measured two aspects of dispersal in the alpine Australian scincid lizard, Niveoscincus micolepidotus: (1) natal dispersal, i.e. shift in home range over the lizard's first year of life, and (2) breeding dispersal, i.e. shifts of home ranges between breeding attempts as adults. On average, displacements were surprisingly small. Female neonates dispersed about twice as far as did males in the same cohort (means of 12 m vs. 6 m). A female's natal dispersal distance was not correlated with her body size or our estimate of physiological performance (sprint speed). However, larger, faster-running male neonates dispersed further than did smaller, slower males. As was the case for neonates, adult females moved significantly further between breeding seasons than did adult males (14.2 m vs. 9.6 m). Because of a female's long gestation period (more than 1 year), two groups of females occur simultaneously in the population, non-ovulated (i.e. with yolking folicles) and pregnant females (i.e. approaching parturition). Females that were not yet ovulated showed a markedly stronger dispersal in response to high reproductive effort (i.e. clutch size in relation to body condition) than did pregnant females. In adult males, body size was negatively correlated with dispersal distance, suggesting that although males have overlapping territories, they exhibit an increasing level of site tenacity with age and/or size. Thus, selection for the relatively more pronounced site tenacity in adult males may have resulted in the more marked philopatric behaviour compared to females also as neonates. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society, 2003, 79, 277,283. [source]


The Application of Magnetic Cell Sorter (MACS) to Detect Fetal Cells in Maternal Peripheral Blood

JOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 3 2001
Dr. Akimune Fukushima
Abstract Objectives: The aim of the present study was to investigate the effectiveness of sorting fetal nucleated red blood cells (FNRBC) from maternal peripheral blood, particularly during early gestation periods, by a combination of specific gravity centrifugation and magnetic cell sorter (MACS). Methods: Without prior knowledge of the gender of the fetus, we determined gender by analyzing a Y-chromosome specific sequence by nested-PCR, using 10 ml of the peripheral blood of healthy primigravida women at different stages of gestation (first trimester: n = 17, second trimester: n = 13, and third trimester: n = 19). The results of this prenatal sex determination were compared to the sex of newborns. Results: The specificity, sensitivity, positive predictive value (PPV) and negative predictive value (NPV) of the present method during the first trimester were 100, 81.8, 100, and 75%, respectively; during the second trimester, 80, 50, 80, and 50%, respectively; and during the third trimester, 25, 63.6, 53.8, and 33.3%, respectively. Conclusion: The results show that this prenatal sex determination method has a highly accurate diagnostic rate during the first trimester, suggesting that it could be developed as a practical, non-invasive prenatal diagnostic technique for use during early gestation periods. [source]


REVIEW ARTICLE: Immunological Paradigms and the Pathogenesis of Ovine Chlamydial Abortion

AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 4 2010
Gary Entrican
Citation Entrican G, Wattegedera S, Wheelhouse N, Allan A, Rocchi M. Immunological paradigms and the pathogenesis of ovine chlamydial abortion. Am J Reprod Immunol 2010 Successful mammalian pregnancy involves complex immunological interactions between the mother and foetus that are not yet fully understood. A number of immunological paradigms have been established to explain the failure of the maternal immune system to reject the semi-allogeneic foetus, mainly based on studies in mice and humans. However, as placental structure, gestation periods and number of concepti per pregnancy can vary greatly between mammals, it is not always clear how applicable these immunological paradigms are to reproduction in other species. Here, we discuss the predictions of three important immunological paradigms in relation to the pathogenesis of ovine enzootic abortion (OEA), a common cause of infectious abortion in sheep and other ruminants. OEA is caused by the intracellular Gram-negative bacterium Chlamydophila abortus that exhibits a tropism for placental trophoblast. The paradigms of particular relevance to the pathogenesis of OEA are as follows: (i) intracellular bacterial infections are controlled by TH1-type CD4+ve T cells; (ii) indoleamine 2,3-dioxygenase is expressed in the placenta to prevent immunological rejection of the semi-allogeneic foetus; and (iii) pregnancy is a maternal TH2-type phenomenon. We discuss the relevance and validity of these paradigms for chlamydial abortion and reproductive immunology in sheep. [source]


Fetal heart rate monitoring from maternal body surface potentials using independent component analysis

ANIMAL SCIENCE JOURNAL, Issue 5 2004
Wenxi CHEN
ABSTRACT The fetal heart rate is indispensable for monitoring the health of unborn cattle fetuses. To monitor the fetal heart rate, a method employing independent component analysis (ICA) to extract the fetal electrocardiogram (fECG) from potentials measured on the maternal body surface and composed of a mixture of the maternal ECG (mECG), fECG, baseline drift and noise is described. A mixing of the raw data was simplified using a linear time-invariant model. To separate the fECG from the mECG, baseline drift, and noise, an ICA strategy was applied, using a hyperbolic tangent as the contrast function and treating mutual information with the minimization principle to find the optimum demixing matrix to derive the fECG from the measured signals. After the feasibility of this method was shown on simulated signals obtained by randomly mixing pure fECG, pure mECG, low frequency sinusoidal drift and noise, real signals from three cloned pregnant Holstein cows with 157, 177 and 224-day gestation periods were used to verify the separation method. The results show that the fECG, mECG, low-frequency sinusoidal drift and noise can be clearly segregated in simulations, and that the fECG, mECG, baseline drift and noise can be successfully derived from real signals. The ICA approach has great potential in effectively detecting the fECG from maternal body surface potentials. [source]


Original Article: Prenatal family support, postnatal family support and postpartum depression

AUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 4 2010
Ri-Hua XIE
Background:, Inadequate social support is an important determinant of postpartum depression (PPD). Social support for pregnant women consists of supports from various sources and can be measured at different gestation periods. Differentiating the effects of social support from different sources and measured at different gestation periods may have important implications in the prevention of PPD. In the family centred Chinese culture, family support is likely to be one of the most important components in social support. Aims:, The aim of this study was to assess the association of prenatal family support and postnatal family support with PPD. Methods:, A prospective cohort study was conducted between February and September 2007 in Hunan, China. Family support was measured with social support rating scale at 30,32 weeks of gestation (prenatal support) and again at 2 weeks of postpartum visit (postnatal support). PPD was defined as Edinburgh Postnatal Depression Scale (EPDS) score ,13. Results:, A total of 534 pregnant women were included, and among them, 103 (19.3%) scored 13 or more on the EPDS. PPD was 19.4% in the lowest tertile versus 18.4% in the highest quartile (adjusted odds ratio: 1.04, 95% confidence interval 0.60, 1.80) for prenatal support from all family members, and PPD was 39.8% in the lowest tertile versus 9.6% in the highest tertile (adjusted odds ratio: 4.4, 95% confidence interval 2.3, 8.4) for postnatal support from all family members. Among family members, support from husband had the largest impact on the risk of developing PPD. Conclusions:, Lack of postnatal family support, especially the support from husband, is an important risk factor of PPD. [source]