33 research outputs found

    The combination of polymorphisms within interferon-γ receptor 1 and receptor 2 associated with the risk of systemic lupus erythematosus

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    AbstractGenetic factors seem to play a significant role in susceptibility to systemic lupus erythematosus (SLE). We previously described the amino acid polymorphism (Val14Met) within the IFN-γ receptor 1 (IFN-γR1), and that the frequency of the Met14 allele in SLE patients was significantly higher than that of the healthy control population [Tanaka et al. (1999) Immunogenetics 49, 266–271]. We also found an amino acid polymorphism (Gln64Arg) within IFN-γ receptor 2 (IFN-γR2). Since the IFN-γ receptor is a complex consisting of IFN-γR1 and IFN-γR2, we searched for the particular combination of two kinds of amino acid polymorphisms found within the IFN-γ receptor which plays a prominent role in susceptibility to SLE. The greatest risk of the development of SLE was detected in the individuals who had the combination of IFNGR1 Met14/Val14 genotype and IFNGR2 Gln64/Gln64 genotype

    Adhesion Is Prerequisite, But Alone Insufficient, to Elicit Stem Cell Pluripotency

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    Primitive mammalian neural stem cells (NSCs), arising during the earliest stages of embryogenesis, possess pluripotency in embryo chimera assays in contrast to definitive NSCs found in the adult. We hypothesized that adhesive differences determine the association of stem cells with embryonic cells in chimera assays and hence their ability to contribute to later tissues. We show that primitive NSCs and definitive NSCs possess adhesive differences, resulting from differential cadherin expression, that lead to a double dissociation in outcomes after introduction into the early- versus midgestation embryo. Primitive NSCs are able to sort with the cells of the inner cell mass and thus contribute to early embryogenesis, in contrast to definitive NSCs, which cannot. Conversely, primitive NSCs sort away from cells of the embryonic day 9.5 telencephalon and are unable to contribute to neural tissues at midembryogenesis, in contrast to definitive NSCs, which can. Overcoming these adhesive differences by E-cadherin overexpression allows some definitive NSCs to integrate into the inner cell mass but is insufficient to allow them to contribute to later development. These adhesive differences suggest an evolving compartmentalization in multipotent NSCs during development and serve to illustrate the importance of cell–cell association for revealing cellular contribution

    Relationship between bovine endometrial thickness and plasma progesterone and estradiol concentrations in natural and induced estrus

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    The objective of this study was to investigate cyclical changes in endometrial thickness in relation to progesterone (P-4) and estradiol-17 beta (E-2) concentrations during natural and induced estrus in 15 cows. In the prostaglandin (PG) F-2 alpha induced estrus group, ultrasonography (USG) at 6-h intervals was used to determine endometrial thickness 48-24 h before the PGF(2 alpha), treatment until 24 h after ovulation (ovulation = Day 0). In the natural estrus group, USG was performed every 48 h from Day 3 to Days 15-18 after the first ovulation, and then every 6 h until 24 h after ovulation. Endometrial thickness was standardized using Day 13 as a reference day. Blood was collected during every USG examination and plasma P-4 and E-2 concentrations were determined. Endometrial thickness of the induced estrus group (n = 11) was greater than that of the natural estrus group (n = 9) between 60 and 12 h before ovulation (P < 0.05). In the natural estrus group, prior to an increase in endometrial thickness, a decrease in P-4 and an increase in E-2 were detected. In the induced estrus group, based on the time of ovulation, an increase in endometrial thickness was detected at the same time of a decrease in P-4 before an increase in E-2. These results suggest that decreases in P-4 concentrations may be a cue to changes in endometrial thickness, while increases in E-2 concentrations appear to sustain and/or enhance these changes

    Relationship between bovine endometrial thickness and plasma progesterone and estradiol concentrations in natural and induced estrus

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    The objective of this study was to investigate cyclical changes in endometrial thickness in relation to progesterone (P_4) and estradiol-17β (E_2) concentrations during natural and induced estrus in 15 cows. In the prostaglandin (PG) |-induced estrus group, ultrasonography (USG) at 6-h intervals was used to determine endometrial thickness 48–24 h before the PGF_ treatment until 24 h after ovulation (ovulation = Day 0). In the natural estrus group, USG was performed every 48 h from Day 3 to Days 15–18 after the first ovulation, and then every 6 h until 24 h after ovulation. Endometrial thickness was standardized using Day 13 as a reference day. Blood was collected during every USG examination and plasma P_4 and E_2 concentrations were determined. Endometrial thickness of the induced estrus group (n = 11) was greater than that of the natural estrus group (n = 9) between 60 and 12 h before ovulation (P < 0.05). In the natural estrus group, prior to an increase in endometrial thickness, a decrease in P_4 and an increase in E_2 were detected. In the induced estrus group, based on the time of ovulation, an increase in endometrial thickness was detected at the same time of a decrease in P_4 before an increase in E_2. These results suggest that decreases in P_4 concentrations may be a cue to changes in endometrial thickness, while increases in E_2 concentrations appear to sustain and/or enhance these changes

    Dynamic cerebral autoregulation after confinement in an isolated environment for 14 days

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    Abstract Background To develop human space exploration, it is necessary to study the effects of an isolated and confined environment, as well as a microgravity environment, on cerebral circulation. However, no studies on cerebral circulation in an isolated and confined environment have been reported. Therefore, we investigated the effects of a 14-day period of confinement in an isolated environment on dynamic cerebral autoregulation. Methods We participated in an isolation and confinement experiment conducted by the Japan Aerospace Exploration Agency in 2016. Eight healthy males were isolated and confined in a facility for 14 days. Data were collected on the days immediately before and after confinement. Arterial blood pressure waveforms were obtained using a finger blood pressure monitor, and cerebral blood flow velocity waveforms in the middle cerebral artery were obtained using transcranial Doppler ultrasonography for 6 min during quiet rest in a supine position. Dynamic cerebral autoregulation was evaluated by transfer function analysis between spontaneous variability of beat-to-beat mean arterial blood pressure and mean cerebral blood flow velocity. Results Transfer function gain in the low- and high-frequency ranges increased significantly (0.54 ± 0.07 to 0.69 ± 0.09 cm/s/mmHg and 0.80 ± 0.05 to 0.92 ± 0.09 cm/s/mmHg, respectively) after the confinement. Conclusion The increases observed in transfer function gain may be interpreted as indicating less suppressive capability against transmission from arterial blood pressure oscillation to cerebral blood flow velocity fluctuation. These results suggest that confinement in an isolated environment for 14 days may impair dynamic cerebral autoregulation. Trial registration UMIN000020703, Registered 2016/01/22
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