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Specific lipid and protein changes characterized term preeclampsia (PRE) and gestational diabetes mellitus (GDM) and novel visualization tools were created to aid in the process.
The impact of the exposure to ionizing radiation in the offspring and next generation has been investigated in the last decades and currently is the subject of study of the ICRP Task Group 121. Studying the effects of radiation exposure in pre-conceptional and post-conceptional phases can be a challenge since potential effects to the fetus vary depending on the stage of fetal development. Epidemiology and radiobiology studies are the two sources of information one can use to correlate the radiation dose to the human body and tissues and the resulting effects. For a proper evaluation of the outcomes of such studies, and a correct appraisal of the exposure/dose-effect relationship, (i) reliable dosimetry, (ii) accurate reporting, and (iii) reproducibility of results are required. Although variables related to dose, including for instance source of radiation, geometry of irradiation, dose rate etc., are usually known, especially in radiobiology studies, often important details of the irradiation are not reported. In conclusion, based on standards developed by the National Cancer Institute (NCI), the National Institute of Allergy and Infectious Disease (NIAID) and the National Institute of Standards and Technology (NIST), a review of the scientific studies used by the UNSCEAR to estimate the risk of hereditary effects, and by the ICRP in its current recommendations, was conducted to evaluate the way dosimetry was reported. Dosimetry and the related uncertainties were not adequately described in the vast majority of those studies. This does not necessarily mean that they do not provide relevant information, however it prevents from a thorough verification and reproduction of their findings. In order to guarantee the reliability and robustness of the process of revision of the estimates of risk and detriment it is therefore considered mandatory to include a careful check of the new relevant literature with regard to the criteria on the completeness and reproducibility of the dosimetric information.
Inhalation and ingestion dose coefficients for the embryo and fetus from intakes of radionuclides by the mother are provided in the International Commission on Radiological Protection (ICRP) Publication 88 for intake of each of 74 radionuclides. To address the many other possible radionuclides to which workers may be exposed, effective dose coefficients were developed for the embryo/fetus for all additional radionuclides addressed in ICRP Publication 107 with half-life of 10 min or more. The general approach was to use the estimated dose to the mother’s uterus during pregnancy as a scalable proxy for the dose to the embryo/fetus. The set of scaling factors used in the study was derived from analyses of the relationships of the dose to the mother’s uterus and the effective dose to the embryo/fetus for the ~400 cases (considering two intake modes and multiple forms of many of the radionuclides) addressed in Publication 88.
Background Brucellosis remains a significant health and economic challenge for livestock and humans globally. Despite its public health implications, the factors driving the endemic persistence ofBrucellaat the human-livestock interface in Tanzania remain poorly elucidated. This study aimed to identify the seroprevalence ofBrucellainfection in livestock and humans within a ranching system and determine associated risk factors for disease endemicity. Methods A cross-sectional sero-epidemiological study was conducted in 2023 in Tanzania’s Karagwe District, involving 725 livestock (cattle, goats, sheep) from 10 herds and 112 humans from associated camps. Seroprevalence was assessed using competitive ELISA while epidemiological data were collected via questionnaires. Generalized Linear Models and Contrast Analysis were used to identify risk factors for infection. Results Overall seroprevalence was 34% in livestock and 41% in humans. Goats exhibited the highest prevalence (69.2%), while cattle had the lowest (22.6%). Mixed-species herds (Odds Ratio, OR = 2.96, CI [1.90–4.60]) and small ruminants-only herds (OR = 6.54, CI [3.65–11.72]) showed a significantly higher risk of seropositivity compared to cattle-only herds. Older cattle (OR = 5.23, CI [2.70–10.10]) and lactating females (OR = 2.87, CI [1.78–4.63]) represented significant risks for brucellosis in livestock. In humans, close contact with animals (OR = 7.20, CI [1.97–36.31]) and handling animals during parturition or aborted fetuses (OR = 2.37, CI [1.01–5.58]) were significant risk factors. Notably, no spatial association was found in seroprevalence between herds and nearby human communities. Conclusion The lack of spatial correlation between livestock and human seroprevalence suggests complex transmission dynamics, potentially involving endemic circulation in livestock and human infections from multiple sources of exposure to livestock. This study highlights the need for comprehensive zoonotic risk education and targeted intervention strategies. Further research is crucial to elucidate transmission pathways and improveBrucellainfection control. This includes developing robust methods for identifying infective species and implementing effective strategies to mitigateBrucellainfection in endemic regions.
Zika virus (ZIKV) infections have been associated with an increased incidence of severe microcephaly and other neurodevelopmental disorders in newborn babies. Passive immunization with anti-ZIKV neutralizing antibodies has the potential to become a feasible treatment or prophylaxis option during pregnancy. Prior to clinical use, such antibodies should be assessed for their ability to block ZIKV passage to the fetus. We used human placental and mammalian cell monolayers that express FcRn and laboratory preparations of anti-ZIKV antibodies as a model system to investigate the disposition of ZIKV/antibody immune complexes (ICs) at the maternal-fetal interface. We further characterized solution properties of the ICs to evaluate whether these are related to in vitro effects. We found that both ZIKV and ZIKV envelope glycoprotein can enter and passage through epithelial cells, especially those that overexpress FcRn. In the presence of ZIKV antibodies, Zika virus entry was bimodal, with reduced entry at the lowest (0.3–3 ng/mL) and highest (µg/mL) antibody concentrations. Intermediate concentrations attenuated inhibition or enhanced viral entry. With respect to anti-ZIKV antibodies, we found that their degradation was accelerated when presented as ICs containing increased amounts of ZIKV immunogen. Of the two monoclonal antibodies tested, the preparation with higher aggregation also exhibited higher degradation. Our studies confirm that intact Zika virus and its envelope immunogen have the potential to enter and be transferred across placental and other epithelial cells that express FcRn. Presence of anti-ZIKV IgG antibodies can either block or enhance cellular entry, with the antibody concentration playing a complex role in this process. Physicochemical properties of IgG antibodies can influence their degradation in vitro.
Respiratory changes and oxygen consumption effects during pregnancy on intrauterine development of rabbit fetus
Prenatal and postnatal growth of rats conceived and reared at different G-intensities from 1.0G (earth gravity) to a maximum of 2.03G were compared. Prenatal growth was not generally impaired but the lung/body mass ratio of 22-day old fetuses at 2.03G was decreased significantly compared to 1.06 controls. Survival of neonatal rats was substantially reduced at 1.71G and 2.03G. Postnatal growth was decreased at the higher G-intensities and showed smaller or no effects at the lower G-intensities. Comparisons of organ/body mass ratios of hyper-G and 1.0G rats at 9 wks of age showed relatively few differences at the lower G-intensities. Postnatal growth of mice at 2.03G was suppressed during the neonatal period but recovered later so that after 9 wks the body mass of females reached and of males approached controls. Results of this preliminary study clearly show the influence of body mass in scaling the effects of hyper-G on the growth and development of and between different animal species.
Alpha-fetoprotein (AFP), a single-chain polypeptide which is synthesized by the liver and yolk sac of the human fetus, provided a model ligand for assessing the effects of microgravity on ligand binding to surface-immobilized model receptor molecules. Monoclonal antibodies, used as receptors for AFP, were immobilized by covalent attachment to latex microparticles. Zero gravity environment was obtained by parabolic flight aboard NASA 930, a modified KC-135 aircraft. Buring the onset of an episode of zero gravity, ligand and receptor were mixed. Timed incubation (20 s) was terminated by centrifugation, the supernatant removed, and microparticies were assessed for bound AFP by immunochemical methods. The extent of binding was not influenced by microgravity, when compared with 1-G controls, which suggests that aberrant cellular activities observed in microgravity are not the simple expression of altered macromolecular interactions.
An ambulatory, passive sensor for use in a fetal monitoring system is discussed. The invention is comprised of a piezoelectric polymer film, combined with a metallic mounting plate fastened to a belt, and electrically connected to a signal processing unit by means of a shielded cable. The purpose of the sensor is to receive pressure pulses emitted by a fetus inside an expectant mother. Additionally, the monitor will filter out pressure pulses arising from other sources, such as the maternal heart.
The hypothesis that the stage of development of rats may affect the availability of various forms of selenium for the activity of glutathione peroxidase (GSHPx) in the rat was experimentally investigated. One experiment evaluated the availability of selenium as selenite or selenomethionine for GSPHx activity during three developmental states in rats: fetus and 7-day old and 14-day old nursing pups. In all tissues studied, GSHPx activity was highest in the 14-day-old pups whose dams were in the selenomethionine group. Rat pups given intraperitoneal selenite had higher liver and kidney GSHPx activity than pups given the same amount of selenium as intraperitoneal selenomethionine. In a second experiment, all dams were fed the same basal diet and pups were weaned to diets containing one of two levels of selenium and one of three forms of selenium (selenite, selenomethionine, or selenocystine). The results also supported the hypothesis these dietary forms of selenium are differentially available for GSHPx activity.
The objective of this feasibility study was to investigate the environmental/treatment stresses in the proposed PARE.04 experiments in a ground based study to determine if these stresses were of sufficient magnitude to compromise the planned shuttle experiments. Eighty pregnant Sprague-Dawley rats were received on day 2 (day l equals day of vaginal plug) of gestation (G2) and on G7 60 were laparotomized to determine the condition of pregnancy and allow assignment to test groups. The five test groups (N equals 10 each group) were as follows: Group 1, nominal flight; Group 2, laparotomy control; Group 3, hysterectomy control; Group 4, vivarium control; Group 5, caesarean delivery. On G17, groups 1, 2, and 5 were subjected to unilateral hysterectomy to obtain fetuses for evaluation. There was no difference in fetal crown-rump length, fetal weight, or placental weight in any of the test groups subjected to unilateral hysterectomy at G17. Animals were allowed to go to term and animals in each group delivered between the morning of G22 and the afternoon of G23. Rats assigned to Group 5 began delivering vaginally prior to the designated time for caesarean section, thus only 2 animals in this group were delivered by caesarean section. After delivery, a blood sample was taken from the dam, and they were euthanized and the thymus and adrenal glands weighed. Pups from experimental dams were tattooed for identification, the anogenital distance of male pups was photographed for later measurement, and all pups placed with foster dams and litter sizes were standardized to 10. On day 7, all pups were euthanized, and pup adrenal glands and thymus weighed. Laparotomy at G7 with or without unilateral hysterectomy at G17, had no effect on pregnancy maintenance or vaginal delivery. There was no difference in maternal adrenal or thymus weights or plasma levels of catecholamines, estradiol, progesterone, or corticosterone. Likewise, there was no difference in the anogenital distance (index of fetal stress) of neonatal male pups, between any of the experimental groups. From days 0-7, weight gain from dams in all experimental groups was similar. Lastly, there was no difference in weights of thymus and adrenal glands in pups euthanized at day 7. Collectively, these data indicate that treatment stresses inherent in the proposed PARE.04 experimental design should not compromise the planned shuttle experiments.
Of all the many potential and real microenvironmental influences, only gravity would appear to have remained relatively constant and ubiquitous for developing organisms. Histo- and organogenesis as well as differential growth of the embryo and fetus may have evolved with a constant environmental factor of gravity. Chick embryos of 2-day and 9-day stages of incubation were flown in an incubator on the Space Shuttle during a 9-day mission. Significant differences in embryo response to this microgravity environment were observed. This paper offers an analysis and suggests mechanisms which may contribute to these results.
The overall goal of this project was to investigate the effects of prolonged weightlessness on the development of the skin in the fetal and newborn rat. Specifically, we used the NASA microgravitational rat model to test the following hypotheses: (1) Exposure of the pregnant rat to microscopy during late gestation will diminish the transport of calcium across the placenta from the mother to the fetus leading to decreases in total epidermal and dermal calcium content; (2) Microgravity will lead to slowing of body growth and diminish the rate of formation of the outermost layer of the epidermis and the stratum corneum; and (3) Microgravity will lead to formation of a stratum corneum with decreased DC electrical resistance and increased permeability to tritiated water.
Rats were shipped to Kennedy Space Center (KSC), Florida, on day 2 of gestation [(G2) (day 1 = morning on which spermatozoa are present in the vagina)] and laparotomized on G7 to determine the number of implantation sites in each uterine horn. On G8, ten pregnant rats meeting flight criteria (at least five implantation sites each horn) were placed into NASA flight cages (animal enclosure modules, AEMS, five rats per cage), loaded onto the mid-deck of the space shuttle Atlantis, and on G9 (November 3, 1994) they were launched into orbit. On gestation day 20, (November 14, 1994) the shuttle returned to Edwards Air Force Base, California and the flight animals were recovered from the shuttle and subjected to unilateral hysterectomy to provide fetal material from one horn to investigators identified by NASA to study selected fetal parameters. After unilateral hysterectomy, the animals were allowed to recover and deliver vaginally. There were three groups (n = 10 each group) of control animals housed at KSC in the study. A synchronous control group, delayed 24 hours with reference to the flight group, received the same surgeries and was housed five rats per AEM and exposed to all flight conditions (identical temperatures, lighting and humidity) except microgravity. Vivarium control group I did not receive any surgery and was housed in the vivarium in clear polycarbonate cages. Vivarium control group 2 received only a unilateral hysterectomy on day 20 of gestation but otherwise was housed like the vivarium control group 1. Control groups were allowed to complete their pregnancy and deliver fetuses from the remaining horn (Synchronous control and vivarium control group 2) or horns (Vivarium control group 1). After surgery, the dams were euthanized and tissues recovered, and the neonates were assigned to foster dams.
This study has been completed, and the following is an update of the results as published. Pregnant rats were flown on the Space Shuttle in the NIH.R I mission for 11 days, and pregnant control rats were maintained in animal enclosure modules in a ground-based chamber under conditions approximating those in flight. Additional controls were in standard housing. The effects of the flight on immunological parameters (including blastogenesis, interferon-gamma production, response to colony stimulating factor and total immunoglobulin levels) of dams, fetuses, and pups was determined.
Head-out water immersion (HOI) has been employed as a remedial treatment for various ills and ailments for many millennia, and total body immersion even longer as protective encapsulation for the mammalian fetus. Two discrete differences between stimuli induced by true microgravity (10(exp -4) g) and HOI are readily apparent. External water pressure on the skin and accompanying negative pressure breathing cause blood to shift headward. Secondly, the gravitational force is ever present during immersion and microgravity, but its effect is essentially neutralized during Earth orbital flight. Thus, the physiological responses to immersion should not be expected to match those during microgravity. Immersion has been used mainly to study and understand kidney function and associated cardiovascular responses for control of body fluid volume and osmotic content, with some application to and simulation of microgravity responses. There is a plethora of data from human HOI studies, but relatively few controlled data from microgravity studies. In general, it appears that physiological responses occur more quickly with water immersion than in microgravity, but this may be due to less rigorous control (voluntary and involuntary) of the preflight state of crew members. The central venous pressure-vasopressin (Gauer-Henry) reflex control for fluid balance may not be of prime importance in microgravity. Gross functions such as reduced body weight and water, level of hypovolemia, decreased isokinetic strength, and lower nitrogen balance found during immersion are qualitatively similar in microgravity, but the mechanisms controlling these and other functions are, for the most part, unclear. Only acquisition of data from well-controlled microgravity experiments will resolve this discrepancy.
The goal of this investigation is to further our understanding of the dynamics of secreting neutron stars and black holes in the hope of using these systems as probes of the physics of strong gravitational fetus. The main focus of this work has been a multi-year program of simultaneous millisecond X-ray timing and spectral observations carried out with the Rossi X-Ray Timing Explorer (RXTE) to perform the X-ray timing and one of the satellites Asca, BeppoSAX, or Chandra to perform X-ray spectral measurements. With the advent of Chandra, we have extended our work to incLude extragalactic X-ray binaries. We conducted a comprehensive study of the X-ray and radio behavior of the Black Hole Candidate (BHC) X-ray transient XTE J1550-564 using RXTE, Chandra, and the Australian Telescope Compact Array (ATCA). We showed that strong radio emission is associated with major X-ray outbursts involving an X-ray state transition, while a compact radio jet is seen in the low/hard X-ray state found in the outburst decay. Interesting, the total energy required to produce the compact jet may be a substantial fraction of the total accretion energy of the system in that state. We also performed a detailed study of the spectral and timing properties of the decay. In joint RXTE/BeppoSAX observations of the neutron-star X-ray binary Cyg X-2, we discovered a correlation between the timing properties (the frequency of the horizontal branch oscillations) and the properties of a soft, thermal component of the X-ray spectrum. d e showed that more det<iiled measurements of this source may lead to constraints on models of the accretion flow and the emission of X- ray from accreting neutron stars. We have completed analysis of RXTE observations of the X-ray transient SAX J1750.8-2900 made after detection of X-ray bursts from the source with the BeppoSAX Wide-Field Camera. We discovered millisecond oscillations in both the persistent emission and in the X-ray bursts.
During parturition, rats exhibit characteristic behavioral expressions of labor. Lordosis contractions, consisting of an elongation of the dams body, are observed beginning several hours prior to neonate births, whereas vertical contractions, repeated rapid lifts of the abdomen, occur immediately preceding the birth of each neonate. We analyzed underlying changes in intrauterine pressure (IUP) using a telemetric sensor that we modified for use in freely-moving rats. This technique enabled us to correlate behavioral expressions of labor contractions with IUP. A small telemetric blood pressure sensor was fitted within a fluid-filled balloon, similar in size to a full term rat fetus. On Gestational day 19 of the rats' 22-day pregnancy, a unit was surgically implanted within the uterus. The dams were simultaneously videotaped, enabling us to directly correlate IUP signals with behavioral expressions of labor contractions. Earlier phases of labor, consisting predominantly of lordosis contractions were characterized by lower pressures relative to later phases during which higher pressures and vertical contractions were frequently observed.