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311.
Our previous research has indicated local expression of ADAMDEC-1, a family of disintegrin and metalloproteinase, was confirmed in the mouse placentas and enhancement was found in the sites for spontaneous abortion. Present study was aimed to identify biological effects of ADAMDEC-1 in pregnancy process. Syngeneic pairs of C57BL/6J mice and heterogenic mating pairs of CBA/J and DBA/2 mice were used. Pregnant mice were treated with recombinant ADAMDEC-1 protein. Vasculogenesis effects was evaluated using the Matrigel plugs including vascular endothelial growth factor singularity or combination with ADAMDEC-1. ADAMDEC-1 single effects were evaluated by tubal formation and proliferation assays using HuEht-1 endothelial cells. Expression of ADAMDEC-1 was not exactly corresponded with the time periods for miscarriage initiation. ADAMDEC-1 was distributed in normal placentas and fetuses, especially at extraembryonic ectoderm, decidua cells, uterine natural killer (uNK) cells in decidua, trophoblasts in labyrinthine zone, and hematopoietic cells in umbilical blood and fetal liver. ADAMDEC-1 treatment did not affect reproductive performances, while it elevated uNK cell recruitment in placenta and enlarged lumen sizes of the intraplacental vessels. In vitro analysis also indicated ADAMDEC-1 promoting effect on tubal formation and cell length of HuEht-1. qPCR analysis showed that ADAMDEC-1 modified placental gene expression especially for linkage of actin filament rearrangement. Our findings suggested that ADAMDEC-1 is correlated on cell shape, stability, and movement via modification of actin cytoskeleton. ADMADEC-1 suspected to regulate cellular activity of endothelial cells, trophoblasts, and uNK cells and may support normal developing of mouse placentas.  相似文献   
312.
Nasal papules and oral ulcers were observed in calves that were group-housed at a dairy farm. The calves were diagnosed with bovine papular stomatitis (BPS) due to parapoxvirus (PPV) infection based on virologic examinations using polymerase chain reaction to detect PPV. To prevent the spread of BPS, we isolated the affected calves, made procedural changes so that the affected herd was managed after the healthy herd, disinfected the bedding with slaked lime, disinfected the stalls and fences with invert soap, and changed the animals’ feed to soft grass which does not damage the oral cavity. As a result, we succeeded in control the infection quickly.  相似文献   
313.
ABSTRACT

The stability of black soil carbon in the deep layers of Japanese volcanic ash soil (i.e., buried A horizons) is often explained by its unique chemical (molecular structure) and physical (associated with short-range-order minerals) recalcitrance. However, the stability of black soil C in buried A horizons may be changed by labile C supply for soil microbes. Here, we hypothesized that the mineralization of black soil C in buried A horizons of Japanese volcanic ash soil could be easily accelerated by a supply of labile C (i.e., a priming effect; PE). To test our hypothesis, we investigated the direction and magnitude of the PE with a buried A horizon in Japan using 13C-labeled glucose (2.188 atom %) in a short-term (21 days) incubation study. We also investigated the effect of mineral nitrogen (N), which could contribute to microbial activity in this incubation study. We found that a positive PE occurred by glucose supply with (182%) or without (181%) mineral N input over the 21-day incubation, and its values were very similar to the PE ratios previously reported in other deep soils. The estimated mean residence time (MRT) of black soil C considering PE was clearly accelerated by glucose supply, regardless of mineral N input, compared with the initial soil MRT. These results strongly support our hypothesis that the mineralization rate of black soil C in buried A horizons is easily accelerated by a labile C supply, and it also demonstrates important implications for the effects of global warming on buried A horizons (e.g., increased root exudation, fine root biomass supply, and N deposition) in Japanese volcanic ash soils.  相似文献   
314.
In order to confirm the pathogenicity ofCistella japonica, inoculation experiments were conducted onto several coniferous trees. Resinous lesions similar to those of the resinous stem canker developed by the inoculation withCi. japonica only onChamaecyparis obtusa. Chamaecyparis trees were heavily affected when inoculated with the fungus in November, but slightly in May and August. Resin flows occurred when inocula ofCi. japonica were put into the holes made on stem barks and on pruning scars. Isolates ofCi. japonica varied greatly in the pathogenicity. On the lesions caused by the fungus, resinous and necrotic areas expanded in fusiform or oblong shape, and resin cysts were formed in inner barks. Beneath some necrotic inner barks, sapwood was suppressed in growth for the damages in cambial cells and stained.Ci. japonica was reisolated from the inoculated lesion tissues, though isolation frequency of the fungus became lower in some lesions two or more years after the inoculation. The results of these inoculations proved thatCi. japonica was the causal agent of the resinous stem canker ofCh. obtusa.  相似文献   
315.
Recent discovery of a phase transition from perovskite to post-perovskite suggests that the physical properties of Earth's lowermost mantle, called the D' layer, may be different from those of the overlying mantle. We report that the electrical conductivity of (Mg0.9Fe0.1)SiO3 post-perovskite is >10(2) siemens per meter and does not vary greatly with temperature at the conditions of the D' layer. A post-perovskite layer above the core-mantle boundary would, by electromagnetic coupling, enhance the exchange of angular momentum between the fluid core and the solid mantle, which can explain the observed changes in the length of a day on decadal time scales. Heterogeneity in the conductivity of the lowermost mantle is likely to depend on changes in chemistry of the boundary region, not fluctuations in temperature.  相似文献   
316.
Some vertebral anomalies in cultured fish arise from unusual environmental conditions during embryogenesis. We investigated the individual and combined teratogenic effects of short‐term hypercapnia and hypoxia on embryos of red sea bream (RSB), Pagrus major. Ten‐somite stage embryos were exposed to hypercapnia (60 and 120 mg/L dissolved carbon dioxide: DCD) and hypoxia (0%, 10%, 25%, 50%, and 75% dissolved oxygen: DO) independently and concomitantly for seven different periods (0, 30, 60, 90, 120, 150 and 180 min) to examine somitic disturbances at hatching, which are prodromal symptoms of centrum defects. Another experiment examined vertebral anomalies in juveniles raised from eggs exposed to hypercapnia (120 mg/L DCD) and hypoxia (10% DO) independently and concomitantly. Short‐time exposures (30–180 min) to hypercapnia (60 and 120 mg/L) and hypoxia (10% DO or less) independently and additively caused larval somitic disturbances and juvenile centrum defects. The results indicate that short‐term hypercapnia and hypoxia generally have the same teratogenic effect on embryos, although there were some differences in the locations of the somitic disturbances and centrum defects, with additive teratogenicity when the conditions were combined. These results suggest the necessity of maintaining appropriate DCD and DO concentrations during egg incubation and transport and during reproduction in recirculating aquaculture.  相似文献   
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