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Damira Avgustinovich Anna Kovner Elena Kashina Natalia Shatskaya Galina Vishnivetskaya Natalia Bondar Maria Lvova 《International journal for parasitology》2021,51(5):353-363
Parasitic food-borne diseases and chronic social stress are frequent attributes of day-to-day human life. Therefore, our aim was to model the combined action of chronic Opisthorchis felineus infection and repeated social defeat stress in C57BL/6 mice. Histological examination of the liver revealed inflammation sites, pronounced periductal fibrosis, and cholangiofibrosis together with proliferation of bile ducts and hepatocyte dystrophy in the infected mice, especially in the stress-exposed ones. Simultaneously with liver pathology, we detected significant structural changes in the cerebral cortex. Immunohistochemical analysis of the hippocampus indicated the highest increase in numerical density of Iba 1-, IL-6-, iNOS-, and Arg1-positive cells in mice simultaneously subjected to the two adverse factors. The number of GFAP-positive cells rose during repeated social defeat stress, most strongly in the mice subjected to both infection and stress. Real-time PCR analysis showed that the expression of genes Aif1 and Il6 differed among the analysed brain regions (hippocampus, hypothalamus, and frontal cortex) and depended on the adverse factors applied. In addition, among the brain regions, there was no consistent increase or decrease in these parameters when the two adverse treatments were combined: (i) in the hippocampus, there was upregulation of Aif1 and no change in Il6 expression; (ii) in the hypothalamus, expression levels of Aif1 and Il6 were not different from controls; and (iii) in the frontal cortex, Aif1 expression did not change while Il6 expression increased. It can be concluded that a combination of two long-lasting adverse factors, O. felineus infection and repeated social defeat stress, worsens not only the hepatic but also brain state, as evidenced behaviorally by disturbances of the startle response in mice. 相似文献
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The tropane alkaloid (TA) scopolamine is suggested to protect Brugmansia suaveolens (Solanaceae) against herbivorous insects. To test this prediction in a natural environment, scopolamine was induced by methyl jasmonate (MJ) in potted plants which were left 10?days in the field. MJ-treated plants increased their scopolamine concentration in leaves and herbivory decreased. These findings suggest a cause?Ceffect relationship. However, experiments in laboratory showed that scopolamine affect differently the performance of the specialist larvae of the ithomiine butterfly Placidina euryanassa (C. Felder & R. Felder) and the generalist fall armyworm Spodoptera frugiperda (J. E. Smith): the specialist that sequester this TA from B. suaveolens leaves was not negatively affected, but the generalist was. Therefore, scopolamine probably acts only against insects that are not adapted to TAs. Other compounds that are MJ elicited may also play a role in plant resistance against herbivory by generalist and specialist insects, and deserve future investigations. 相似文献
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MN Kaggwa N Straubinger-Gansberger M Schagerl 《African Journal of Aquatic Science》2018,43(2):123-129
Nine small artificial dams located in different climatic regions of Kenya were studied. The local communities use the stored water for various purposes, such as irrigation, domestic use, watering of livestock and cage fish farming. Such intense use is commonly accompanied by eutrophication, including fast growth of cyanobacteria, which at times produce cyanotoxins threatening human and animal life. We studied the pelagic community, analysed abiotic variables and identified microcystins by means of high performance liquid chromatography and ELISA kits at monthly intervals over a period of one year. Mass spectrometry (MALDI-TOF MS) was used to identify structural variants of microcystins by their protonated masses (M + H). Three dams contained microcystins, with the highly toxic Microcystin-LR being identified as the most prominent substance. Cell content of the toxin varied from 7.2 to 686.7 fg cell?1. Basic limnological variables that indicate the probability of toxin presence were also recorded. Non-parametric Mann–Whitney U-test revealed significant differences in soluble reactive phosphorous, nitrate-N, water depth, total hardness and post-Nauplii stages sampled between toxin-producing and non-toxin-producing dams. Although most of the samples did not contain high amounts of cyanobacteria, the cyanotoxin-problem was evident, suggesting the need for regular cyanotoxin monitoring programs. 相似文献
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Thirty five females and 15 males of New Zealand White mature rabbits about 6 months of age, were assigned to 1–5 dietary treatments (7 does+3 bucks for each): uncontaminated control diet, naturally aflatoxin contaminated diet without or with 1,2 and 3% bentonite. Rabbit fed with the aflatoxin-diet had a decreased (P<0.01 or 0.05) physical semen characteristics of bucks and a reproductive performance traits of does. The values of conception rate (%), gestation length (days), litter size (n) and litter weights (g) at birth and viability (%) of litters of doe rabbits, fed with the aflatoxin-diet, recorded, respectively: 64.5; 31.0; 4.4; 275.0 and 57.1 versus 85.6; 30.3; 7.9; 508.0; and 100 for those fed with the uncontaminated diet. Addition of bentonite to the aflatoxin contaminated diet improved in general the physical semen characteristics of buck and reproductive performance traits of doe rabbits. The results of the study demonstrate that adding 1% of Egyptian raw bentonite to the naturally aflatoxin contaminated rabbit diets can provide an effective, cheap and safe practical technique for preventing the aflatoxicosis in mature rabbits. 相似文献
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Fibroblasts obtained from biopsied material and lymphocytes from patients with homocystinuria were studied for repair activity using the criterion of repair of DNA breaks induced by 4-nitroquinoline 1-oxide and gamma-irradiation and criteria of reactivation and induced mutagenesis of vaccinia virus. Lymphocytes showed defective DNA repair for all these criteria. In fibroblast cultures, the inhibition of cell-repair activity for the gamma-type was retained. The number of spontaneous and gamma-induced virus mutations increased as passaging of fibroblasts proceeded. 相似文献
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The properties of alpha-ketoglutarate dehydrogenase with non-interacting active sites were investigated. The substrate and coenzyme saturation curves are found to be hyperbolic, which is consistent with the absence of cooperativity between the active sites of the enzyme. The peculiarities of KGD of this form, determining its functional properties, were revealed. Thus, 6 cysteine residues of the enzyme possess different properties in comparison with the form of the enzyme with interacting active sites. 3 Sulfhydryl groups of the "non-cooperative" enzyme form were rapidly oxidized in the process of the enzyme isolation and storage; thereafter they could not be reduced by dithiols. Three other cysteine residues are probably involved in the formation of disulfide bonds. Two of them are supposed to form intramolecular disulfide, whereas the third one is thought to be modified by some low molecular weight disulfide. The reduction of these sulfhydryl groups by dithiols is shown to be accompanied by the appearance of the kinetic cooperativity with respect to the substrate. It is suggested that the thiol/disulfide exchange in vivo can regulate a reversible conversion of the "non-cooperative" KGD form into one with interacting sites. 相似文献
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Masanori?Nakaem-nakae@cc.kochi-u.ac.jp; KS fishssk@cc.kochi-u.ac.jp" title="MN m-nakae@cc.kochi-u.ac.jp; KS fishssk@cc.kochi-u.ac.jp" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author Kunio?Sasaki 《Ichthyological Research》2004,51(4):327-336
Homologies of the adductor mandibulae muscles in eight families of Tetraodontiformes were hypothesized from the branching patterns of ramus mandibularis trigeminus. Insertions of the muscles to the upper or lower jaw were weak indicators of homology, migrations of the sites occurring frequently in A1, A2, A2, and A3. In monacanthids, tetraodontids, and diodontids, A1 tended to be split into numerous subsections, whereas in aracanids and ostraciids, A3 was highly developed, comprising three or four subsections. In tetraodontids, A2 was found to be a composite of A1 subsection and A2. The methods of and limits to applying nerve branching patterns to muscle homology are discussed. A new naming system that reflects both muscle homologies and insertions is proposed. 相似文献