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51.
The results of using enzyme immunoassay and latex preparations for the diagnosis of rotavirus gastroenteritis are presented. High effectiveness of the enzyme immunoassay system developed in the USSR with latex diagnostic agents, such as Rotalex (Orion Diagnostica, Finland), Slidex Rota Kit (BioMérieux, France), The Wellcome Rotavirus Latex Kit (Wellcome Foundation Ltd., Great Britain), 48-63% and 21-41% respectively, has been noted. The results of the comparison of the system developed in the USSR with Wellcozyme Rotavirus, an enzyme immunoassay system manufactured by Wellcome Foundation Ltd. (Great Britain), are practically comparable. The results of the block test and the confirmation test used for control indicate that the Soviet preparation is specific. Materials on the practical evaluation of the assay system at health institutions are presented. Good prospects for the use of this system in the diagnosis of rotavirus gastroenteritis, as well as in the realization of epidemiological surveillance on this infection, are substantiated.  相似文献   
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Contact hypersensitivity (CHS) is a T cell response to hapten skin challenge of sensitized individuals proposed to be mediated by hapten-primed CD8 cytolytic T cells. Effector CD8 T cell recruitment into hapten challenge sites to elicit CHS requires prior CXCL1- and CXCL2-mediated neutrophil infiltration into the site. We investigated whether neutrophil activities directing hapten-primed CD8 T cell skin infiltration in response to 2,4-dinitro-1-fluorobenzene (DNFB) required Fas ligand (FasL) and perforin expression. Although DNFB sensitization of gld/perforin(-/-) mice induced hapten-specific CD8 T cells producing IFN-γ and IL-17, these T cells did not infiltrate the DNFB challenge site to elicit CHS but did infiltrate the challenge site and elicit CHS when transferred to hapten-challenged naive wild-type recipients. Hapten-primed wild-type CD8 T cells, however, did not elicit CHS when transferred to naive gld/perforin(-/-) recipients. Wild-type bone marrow neutrophils expressed FasL and perforin, and when transferred to sensitized gld/perforin(-/-) mice, they restored hapten-primed CD8 T cell infiltration into the challenge site and CHS. The FasL/perforin-mediated activity of wild-type neutrophils induced the expression of T cell chemoattractants, CCL1, CCL2, and CCL5, within the hapten-challenged skin. These results indicate FasL/perforin-independent functions of hapten-primed CD8 T cells in CHS and identify new functions for neutrophils in regulating effector CD8 T cell recruitment and immune responses in the skin.  相似文献   
55.
Data on the study of the epidemiology of rotavirus infection in Leningrad   总被引:1,自引:0,他引:1  
The results obtained in the study of rotavirus infection in Leningrad in 1984-1987 are presented. Enzyme immunoassay techniques were used for the examination of 4,715 children aged 0-14 years and 1,162 adults with diagnosed acute enteral infection of unknown etiology, as well as the control group of 556 of healthy children aged 0-6 years and 77 healthy adults. The rotavirus antigen was detected in 1.210 sick children (25.7%) and 133 sick adults (11.4%), as well as in 6 healthy children (1.1%), but not detected in healthy adults. The following epidemiological regularities of rotavirus infection were established: the highest sick rate among children aged 0-2 years and a low level of rotavirus carriership among healthy persons; the seasonal character of rotavirus infection, its outbreaks occurring in winter and the epidemic periods varying in their character and duration in different years; the prevailing role of rotaviruses in the development of winter rises of acute enteral infection of unknown etiology in the city among children aged 0-2 years. The problem of the respiratory syndrome in rotavirus diarrhea is discussed. The rotavirus antigen was detected in 39 out of 144 children (27%) with diagnosed acute respiratory virus diseases and in 4 out of 99 nasopharyngeal washings (4%) from diarrhea patients. Adenoviruses were shown to play an insignificant role in the etiology of diarrhea (10% of cases).  相似文献   
56.
In cell suspension of Desulfovibrio desulfuricans B-1388, oxidation of CO as the only energy source is associated with reduction of SO42-. After a 2-h incubation of cells in 8% CO, 81% of the gas is converted. Oxidation of 1 mole CO results in formation of 0.23 mole H2S. Intracellular ATP content increases from 2.5 (control) to 8.3 nmoles/mg (during CO conversion). Dinitrophenol inhibits sulfate reduction and CO oxidation. CO dehydrogenase was detected in cytoplasmic and membrane cell fractions (59 and 34%, respectively).  相似文献   
57.
Equilibrium maintenance during standing in humans was investigated with a 3-joint (ankle, knee and hip) sagittal model of body movement. The experimental paradigm consisted of sudden perturbations of humans in quiet stance by backward displacements of the support platform. Data analysis was performed using eigenvectors of motion equation. The results supported three conclusions. First, independent feedback control of movements along eigenvectors (eigenmovements) can adequately describe human postural responses to stance perturbations. This conclusion is consistent with previous observations (Alexandrov et al., 2001b) that these same eigenmovements are also independently controlled in a feed-forward manner during voluntary upper-trunk bending. Second, independent feedback control of each eigenmovement is sufficient to provide its stability. Third, the feedback loop in each eigenmovement can be modeled as a linear visco-elastic spring with delay. Visco-elastic parameters and time-delay values result from the combined contribution of passive visco-elastic mechanisms and sensory systems of different modalities  相似文献   
58.
The role of tumor-produced chemokines in the growth of malignancies remains poorly understood. We retrieved an in vivo growing MCA205 fibrosarcoma and isolated tumor cell clones that produce both CXCL9/monokine induced by IFN-gamma (Mig) and CXCL10/IFN-gamma-inducible protein 10 following stimulation with IFN-gamma and clones that produce IFN-gamma-inducible protein 10 but not Mig. The Mig-deficient variants grew more aggressively as cutaneous tumors in wild-type mice than the Mig-producing tumor cells. The growth of Mig-expressing, but not Mig-deficient, tumor cells was suppressed by NK and T cell activity. Transduction of Mig-negative variants to generate constitutive tumor cell production of Mig resulted in T cell-dependent rejection of the tumors and in induction of protective tumor-specific CD8(+) T cell responses to Mig-deficient tumors. The results indicate a critical role for tumor-derived Mig in T cell-mediated responses to cutaneous fibrosarcomas and suggest the loss of Mig expression as a mechanism used by tumor cells to evade these responses.  相似文献   
59.
Ovarian cancer ascites is a native medium for cancer cells that allows investigation of their secretome in a natural environment. This medium is of interest as a promising source of potential biomarkers, and also as a medium for cell–cell communication. The aim of this study was to elucidate specific features of the malignant ascites metabolome and proteome. In order to omit components of the systemic response to ascites formation, we compared malignant ascites with cirrhosis ascites. Metabolome analysis revealed 41 components that differed significantly between malignant and cirrhosis ascites. Most of the identified cancer-specific metabolites are known to be important signaling molecules. Proteomic analysis identified 2096 and 1855 proteins in the ovarian cancer and cirrhosis ascites, respectively; 424 proteins were specific for the malignant ascites. Functional analysis of the proteome demonstrated that the major differences between cirrhosis and malignant ascites were observed for the cluster of spliceosomal proteins. Additionally, we demonstrate that several splicing RNAs were exclusively detected in malignant ascites, where they probably existed within protein complexes. This result was confirmed in vitro using an ovarian cancer cell line. Identification of spliceosomal proteins and RNAs in an extracellular medium is of particular interest; the finding suggests that they might play a role in the communication between cancer cells. In addition, malignant ascites contains a high number of exosomes that are known to play an important role in signal transduction. Thus our study reveals the specific features of malignant ascites that are associated with its function as a medium of intercellular communication.Ovarian cancer is the sixth most frequently occurring cancer among the gynecological cancers and accounts for about 5% of all new female cancer cases according to the 2012 data (World Health Organization International Agency for Research on Cancer www.globocan.iarc.fr). Epithelial ovarian cancer registered in 90% of ovarian cancer cases. The rate of mortality from ovarian cancer holds first place among the other gynecological cancers, largely because of the asymptomatic progression of the disease, especially at its early stages, and a lack of adequate screening tests, which leads to late detection, typically only after the cancer has spread to adjacent structures. In such a case, the five-year survival rate is only 25% to 40%, whereas it can be as high as 90% if the cancer is diagnosed early. Unfortunately, ovarian cancer is diagnosed early in less than 20% of the total number of cases (International Agency for Research on Cancer). The main methods for primary diagnostics include transvaginal ultrasound and blood biomarker analyses such as with cancer antigen 125 (CA125),1 epididymis protein-4 (HE4), and the OVA1 multiparametric (CA125, β2-microglobulin, transferrin, and apolipoprotein A1) tests. The OVA1 test is mainly applied to evaluate the malignancy of a tumor-like pelvic mass, and the other two markers are used to monitor disease progress and estimate treatment efficacy, as they are not highly specific for ovarian cancer and thus produce a high percentage of false-positive results (1). Therefore, the search for specific and sensitive markers for the early diagnosis of ovarian cancer is an urgent problem, although the development of new, efficient methods for treatment of the disease at late stages also remains of critical importance.One of the symptoms associated with late-stage ovarian cancer is excessive fluid accumulation in the abdominal cavity, known as ascites. Mechanisms of malignant ascites formation involve lymph obstruction, activation of mesothelial cells as a result of the metastatic process, and increased vessel permeability due to the secretion of growth factors (2, 3). Therefore, malignant ascites is enriched by tumor cells and soluble growth factors that may be associated with the processes of invasion and metastasis. Thus, ascites provides a native medium for cancer cells and creates an opportunity to investigate the ovarian cancer cell secretome in its natural environment (as distinct from cancer cell cultures in vitro) (2).Omics studies enable us to understand physiological information at different levels (47). Considering the highly diverse features of information obtained from each omics platform, one could expect that combinations of different omics should provide highly comprehensive views on special features of the cancer cell secretome. Studies of ascites with the use of omics technologies could not only help us understand the peculiarities of the vital activity of cancer cells in the organism, but also elaborate new therapeutic methods. However, until now, proteomic studies of ovarian cancer ascites have been exceptionally directed at the search for potential biomarkers of this cancer (3, 810). Investigation of ascites is also interesting beyond the protein level. In particular, small molecules—metabolites—are known to be involved in intercellular communication. However, in metabolome studies, to our knowledge, metabolites from ovarian cancer ascites have not been explored at all; only metabolomic analysis of urine and serum has been described in the literature for this type of cancer (1113).It is important to note that ascites accumulation can be caused by various pathologies—for example, liver cirrhosis (81% of all cases), heart diseases (2%), tuberculosis (3%), and 10% of all cases associated with malignancy (10%). The most common cancer associated with ascites is ovarian cancer, accounting for 38% of malignant ascites occurring in females (2). In this study, we compared ascites of different etiologies, formed in the course of ovarian cancer and portal alcoholic cirrhosis. Thus, we not only extended our knowledge of the protein composition and filled in gaps regarding the metabolome, but also elucidated specific features of malignant ascites composition.  相似文献   
60.
We used Bayesian statistics to investigate the demographic history of the walleye pollock in the sea of Okhotks based on polymorphisms of sequences of the Nd2 and Cytb mitochondrial genes. We determined the average age for the Most Recent Common Ancestor (MRCA) as 44.1 ± 2 and 52.6 ± 1.3 thousand years, respectively, for Nd2 and Cytb. These findings suggest that demographic expansion of the Okhotsk Sea pollock began 10–12 thousand years ago, which coincides with the period of global changes in the sea level during the Late Pleistocene-Early Holocene eras.  相似文献   
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