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To clarify the roles of granulated metrial gland (GMG) cells for successful pregnancy in rats, GMG cells in beige rats (genotype: DA-bg/bg), whose NK cells show lysosomal dysfunction because of abnormalities in cytoplasmic granules, were examined in mid- and late-pregnancy by light and electron microscopies. The GMG cells of beige rats were significantly less in number than those of the two controls (genotypes: DA-bg/+ and DA-+/+) in mid- and late-pregnancy, and this accompanied a low reproductive performance in the beige rats. The size of intracellular granules in the GMG cells of the beige rats was larger than for the two controls on each corresponding day of pregnancy. These results suggest that the activity of rat GMG cells and peripheral NK cells might be influenced by the beige gene, which is involved in reproductive performance.  相似文献   
2.
This study characterised muscle fibres in trunk, forelimb and hindlimb muscles of three bat species: little Japanese horseshoe (Rhinolophus cornutus), greater horseshoe (Rhinolophus ferrumequinum) and Egyptian fruit (Rousettus aegyptiacus). Twenty-seven muscles from trunk, forelimb and hindlimb were dissected, weighed and analysed by immunohistochemistry and sodium didecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and determined their cross-sectional areas (CSA). Results showed that Type IIa and Type IIa/x made the highest proportion of total muscle mass. Moderate proportion was formed by Type IIb. Type I and IIx appeared at very low levels in all bats. Type IIb was the only fibre type detected in patagial muscles in wing membrane of greater horseshoe while other fibre types were not observed. Type I muscle fibres were very few and appeared infrequently in fifteen muscles of Egyptian fruit and in only one muscle in each, greater horseshoe and little Japanese horseshoe. Type IIx was also detected in three muscles in greater horseshoe and only one muscle in Egyptian fruit but none in little Japanese horseshoe. The highest average CSA μm2 was detected in Type IIb and values were 734.2μm2 for LHB; 1537.9μm2 for GHB and 1,720.9μm2 for EFB. Lowest and undetermined values were observed for Type I and IIx. These data demonstrate that Type IIa, IIa/x and IIb form significant proportion of adult bat muscle mass and Type IIb is the largest fibre type. The distribution pattern is suggestive of specialised functions of the fibres in relation to orientation and speed of bats during flight.  相似文献   
3.
ABSTRACT:   In this paper, the authors report the detection of alanine racemase activity in the marine diatom Thalassiosira sp. Since the Thalassiosira sp. was cultured under germ-free conditions, it appeared that D-alanine was not derived from bacteria but was produced through catalysis by algal alanine racemase. The rate of conversion of L-alanine to D-alanine was approximately the same as that for the reverse reaction, and the enzyme catalyzed the equilibration of the D- and L-forms. The crude enzyme preparation obtained from the cells at the stationary phase of the growth cycle had an optimal pH of approximately 9.5. The Lineweaver–Burk analysis showed that the K m for D- and L-alanine was 16.5 mM and 29.4 mM, respectively. It appears that the enzyme is highly specific for D- or L-alanine because it does not catalyze the racemization of other amino acids. In addition, after gel filtration, the enzyme did not require exogenous pyridoxal 5'-phosphate (PLP) for its activity, however, the effects of several chemicals suggest that the enzyme may be PLP-dependent. The enzyme is more similar to that found in invertebrates when compared with that found in bacteria. This is the first report on the occurrence of alanine racemase activity in the microalga Thalassiosira sp.  相似文献   
4.
Grapiprant is an analgesic and anti‐inflammatory drug in the piprant class that was approved in March 2016 by FDA's Center for Veterinary Medicine for the control of pain and inflammation associated with osteoarthritis (OA) in dogs. Grapiprant functions as a selective antagonist of the EP4 receptor, one of the four prostaglandin E2 (PGE2) receptor subtypes. The EP4 receptor mediates PGE2‐elicited nociception, and grapiprant has been shown to decrease pain in several rat inflammatory pain models. It was also effective in reducing pain associated with OA in humans, providing evidence for its mechanism of action in these species. The estimated canine efficacy dose of between 1.3 and 1.7 mg/kg, p.o. with a methylcellulose suspension, once a day, was predicted based on calculations from comparative affinity of grapiprant to the dog, rat, and human EP4 receptors, serum protein binding, effective doses defined in rat models of pain and inflammation, and human clinical studies. The results of this study guided the doses to be tested in the pilot study and demonstrated the usefulness of the efficacy dose prediction method. The approved commercial tablet dose of grapiprant is 2 mg/kg once a day for the control of pain and inflammation associated with OA in dogs.  相似文献   
5.
ABSTRACT:   The described analytical method for histamine determination in fish and seafood consists of sample extraction, adsorption onto a paper disc, application of the paper disc onto electrophoresis paper, electrophoresis for only 10 min, drying, and color developing by Pauly's reagent. Histamine can be satisfactorily detected and completely separated from histidine, carnosine and other Pauly reagent-positive compounds. This method does not require expensive instrumentation and any tedious pretreatment to eliminate potential interference by other imidazole compounds, such as histidine or carnosine. This method can be used to detect histamine in multiple fish and seafood samples simultaneously that contain as little as 15 p.p.m. histamine (1.5 mg/100 g).  相似文献   
6.
In 1995 and 1996 thirteen Siberian cranes (Grus leucogeranus) were fitted with satellite transmitters on the breeding grounds in northeastern Siberia. Eleven of these 13 birds were successfully satellite tracked, and five of these 11 provided complete migratory information from their breeding grounds in Yakutia, Siberia, to their wintering area at Poyang Lake, in China. Several stopover sites were identified, the most important being in Qiqihar-Baicheng (China), Shuangtaizi River delta (China), and Yellow River delta (China). Birds rested more frequently in Russia than in China, suggesting availability of suitable wetland habitat in Russia and absence of adequate, suitable wetland habitat in China. Wintering habitat in China also faces numerous threats. Habitats utilized by Siberian cranes are also important to other threatened wetland birds that have been satellite-tracked recently. If Siberian crane habitat needs fail to be addressed, this critically endangered species will be further endangered.  相似文献   
7.
ABSTRACT:   High levels of free d -alanine were found in the muscle of a marine gastropod Cellana grata that inhabited the intertidal zone, and alanine racemase activity was detected in the muscle. The authors purified alanine racemase from the muscle of C. grata to characterize its enzymological properties. The molecular mass of the enzyme was estimated to be 40.5 kDa by sodium dodecylsulfate-polyacrylamide gel electrophoresis and 41.4 kDa by gel filtration, suggesting that the enzyme was monomeric in nature. Kinetic experiments, performed using the purified enzyme, revealed that the Lineweaver-Burk plot for d -alanine as a substrate resulted in a K m value of 20.4 mM, and the value for l -alanine was 43.0 mM. Of the several types of amino acids tested, alanine was found to be the specific substrate for the enzyme. In the measurement of alanine racemase activity, exogenous pyridoxal 5'-phosphate (PLP) was not required for the enzyme activity; however, aminooxyacetic acid, hydroxylamine and phenylhydrazine, which inhibit PLP-dependent enzymes, strongly inhibited the enzyme activity. These results suggest that the enzyme is PLP-dependent. This is the first report on the purification and some properties of alanine racemase in a marine gastropod.  相似文献   
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