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121.
Ekaterina A. Litvinova Elena P. Goncharova Alla M. Zaydman Marina A. Zenkova Mikhail P. Moshkin 《PloS one》2010,5(3)
Background
The scent from receptive female mice functions as a signal, which stimulates male mice to search for potential mating partners. This searching behavior is coupled with infection risk due to sniffing both scent marks as well as nasal and anogenital areas of females, which harbor bacteria and viruses. Consideration of host evolution under unavoidable parasitic pressures, including helminthes, bacteria, viruses, etc., predicts adaptations that help protect hosts against the parasites associated with mating.Methods and Findings
We propose that the perception of female signals by BALB/c male mice leads to adaptive redistribution of the immune defense directed to protection against respiratory infection risks. Our results demonstrate migration of macrophages and neutrophils to the upper airways upon exposure to female odor stimuli, which results in an increased resistance of the males to experimental influenza virus infection. This moderate leukocyte intervention had no negative effect on the aerobic performance in male mice.Conclusions
Our data provide the first demonstration of the adaptive immunological response to female odor stimuli through induction of nonspecific immune responses in the upper respiratory tract. 相似文献122.
ETIENNE KORNOBIS SNÆBJÖRN PÁLSSON BJARNI K. KRISTJÁNSSON JÖRUNDUR SVAVARSSON 《Molecular ecology》2010,19(12):2516-2530
Two endemic groundwater arthropod crustacean species, Crangonyx islandicus and Crymostygius thingvallensis, were recently discovered on the mid‐Atlantic volcanic island of Iceland. The extent of morphological differences from closest relatives, endemism, along with the geographic isolation of Iceland and its complete coverage by glaciers 21 000 years ago, suggests that these two species have survived glaciation periods in sub‐glacial refugia. Here we provide strong support for this hypothesis by an analysis of mitochondrial genetic variation within Crangonyx islandicus. Our results show that the species is divided into several distinct monophyletic groups that are found along the volcanic zone in Iceland, which have been separated by 0.5 to around 5 million years. The genetic divergence between groups reflects geographic distances between sampling sites, indicating that divergence occurred after the colonization of Iceland. The genetic patterns, as well as the dependency of genetic variation on distances from the tectonic plate boundary and altitude, points to recent expansion from several refugia within Iceland. This presents the first genetic evidence of multicellular organisms as complex as crustacean amphipods which have survived glaciations beneath an ice sheet. This survival may be explained by geothermal heat linked to volcanic activities, which may have maintained favourable habitats in fissures along the tectonic plate boundary in Iceland during glaciations. 相似文献
123.
Murat Arslan Fatih Korkmaz Seyda Tacer-Tanas Telat Yanik Mustafa Erat Aliaksandr Slukvin Roza Goncharova 《Zeitschrift fur angewandte Ichthyologie》2021,37(6):942-949
We aimed to investigate the influence of dietary vitamin E and diludine on growth and lipid peroxidation (malondialdehyde; MDA) in rainbow trout. Fish (1.5 g) were fed different dietary levels of vitamin E (0, 50 and 100 mg/kg) and diludine (0, 0.5 and 1 g/kg) for 10 weeks. Growth performance and feed conversion ratio (FCR) were significantly affected by dietary vitamin E (p < .05) but not diludine. Fish fed 50 mg/kg dietary vitamin E with no diludine had significantly better growth and lower FCR than those fed vitamin E free diets. Liver vitamin E content was significantly influenced by dietary vitamin E and diludine (p < .05). The highest hepatic vitamin E was in fish fed the highest dietary vitamin E and diludine levels. Hepatic MDA level was significantly affected by dietary vitamin E and diludine (p < .05), decreasing with the increase in both dietary vitamin E and diludine. According to our results, diludine had no significant effect on growth; however, decreased hepatic lipid peroxidation independent of vitamin E. Our results reveal that 50 mg/kg vitamin E content is suitable for optimal growth and FCR in rainbow trout juveniles. However, dose dependent effects of dietary diludine remain uncertain and need further researches. 相似文献
124.
Olga A. Filatova Briana H. Witteveen Anton A. Goncharov Alexei V. Tiunov Maria I. Goncharova Alexander M. Burdin Erich Hoyt 《Marine Mammal Science》2013,29(3):E253-E265
Humpback whales feed on a variety of prey, but significant differences likely occur between regional feeding grounds. In this study, the diets of humpback whales were analyzed by comparing stable isotope ratios in animal tissues at three humpback whale feeding grounds in the Russian Far East: Karaginsky Gulf, Anadyr Gulf, and the Commander Islands. Anadyr Gulf is a neritic zone far from a shelf break, Karaginsky Gulf is a neritic zone close to a shelf break, and the Commander Islands represent an open oceanic ecosystem where whales feed off the shelf break. Samples from the Commander Islands had the lowest mean δ13C and δ15N values (mean ± SE: δ13C = ?18.7 ± 0.1, δ15N = 10.4 ± 0.1) compared to the samples from Karaginsky Gulf (δ13C = ?17.2 ± 0.1, δ15N = 12.7 ± 0.2) and Anadyr Gulf (δ13C= ?17.8 ± 0.1, δ15N = 14.0 ± 0.4). The samples from Anadyr Gulf had the highest δ15N values, while the samples from Karaginsky Gulf had the highest δ13C values. Both δ13C and δ15N values differed significantly among all three areas. Our data support the hypothesis that humpback whales tend to feed on fish in neritic areas and on plankton in deep oceanic waters. 相似文献
125.
Determination of the secretory activity of the stomach and ultrasound scanning of human gastroduodenal organs and vessels
in experiments with −12° and −15° head-down tilting (HDT) hypokinesia were performed. As a result of short-term (12–24 h)
HDT hypokinesia with the minimized hypokinesia factor, parenchymatous organs enlarged, and the walls of hollow organs thickened.
Enhanced blood filling of abdominal veins was accompanied by elevated pepsinogen levels in blood and urine and increased gastric
contents in fasting subjects. The increased tonicity of the pylorus and the delayed evacuation of stomach contents indicated
the activation of hydrochloric acid secretion. Simultaneously, the bile and pancreatic juice were secreted more profusely,
and the intestinal contents in the duodenum increased. It has been shown that the modeled enhancement of blood filling of
abdominal veins stimulates gastric secretion on an empty stomach, which is accompanied by activation of secretion in the liver
and pancreas. 相似文献
126.
The isolation of the native hexokinase isozyme II possessing a high adsorptive capacity is described. This property underlies the adsorption mechanism responsible for the control of the hexokinase activity in the cell and is realized only under conditions of the structural integrity of the enzyme. The latter is due, primarily, to the functional state of the specific adsorption domain which provides the specific interaction of hexokinase isozyme II with biological membranes. The criteria of nativity of skeletal muscle hexokinase were elaborated. A procedure for obtaining highly purified native hexokinase isozyme II from rat skeletal muscle was developed. 相似文献
127.
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129.
Two types of organogenic carbonate buildups (bryalgal and algal-microbialite) occurring for approximately 11 Ma from the Middle
through to the Late Miocene in the Euxine-Caspian Basin are considered. Four main stages in the formation of these structures
are established: Chokrakian-Karaganian, Early-Middle Sarmatian, Maeotian, and a specific Late Sarmatian one. Each of the first
three stages began with bryalgal bioherms that, during the growing basins’ isolation, transformed into algal-microbialite
buildups. Only bryalgal buildups are found in the Late Sarmatian Basin. 相似文献
130.