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1.
Bleomycin produces pulmonary fibrosis in mice when given as a single intratracheal instillation or as multiple subcutaneous injections. Both models are associated with a significant deposition of collagen in the lungs but differ in the location of the initial lesions. Intratracheal instillation of bleomycin directs lesions to peribronchial or peribronchiolar sites, whereas subcutaneous injection produces lesions in subpleural and perivascular locations. It was therefore of interest to analyse the bronchoalveolar lavage (BAL) fluid for differences in the cellular composition, especially of intraepithelial T lymphocytes characterised by the expression of the integrin E7.Intracheal instillation of bleomycin induced a 5 to 6 times higher number of neutrophils and lymphocytes in BAL fluid than the subcutaneous model. Furthermore, intratracheal instillation of bleomycin induced the infiltration of eosinophilic neutrophils, a peculiar subtype of neutrophils often found in rodents, which were not found in BAL after subcutaneous injection of bleomycin. In both models of bleomycin injection, however, CD4+, CD8+, NK, and T lymphocytes were detected with dominance of the CD4+ T cell population. Analysis of the expression of the integrin E7 revealed similar numbers of E7+ cells in the CD4+ and T cell populations in both models but significantly lower numbers of E7+ T cells were found in the BAL fluid within the CD8+ T cell population after subcutaneous injection of bleomycin compared to intratracheal instillation.These results show that a difference in route of bleomycin administration not only causes changes in the localisation of the lesions but that this variation may be reflected in alterations within the BAL leucocyte population especially within the intraepithelial T lymphocytes.  相似文献   

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Experiments on Wistar rats showed that acute poisoning with chemicals in a dose of 0.75 LD50 (dimethyl dichlorovinyl phosphate, sarin, VX substance, sulfur yperite, lewisite, tetraethyl lead, dichloroethane) inhibiting platelet acetylcholine esterase, -naphthyl-AS-acetate esterase, and -naphthyl-butyrate esterase suppressed T cell-mediated immune reactions.  相似文献   

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We studied the content and expression of mRNA for estrogen receptors receptors- and - in breast tumors before and after 3-month neoadjuvant hormone therapy with antiestrogen tamoxifen and/or aromatase inhibitors. Expression of estrogen receptors- and - was most often detected in ER+PR+ tumors and most significantly decreased in these neoplasms after exemestane therapy. Immunocytochemical and radioligand assays showed that tamoxifen and anastrozole have little effect on the number of estrogen receptors- The number of progesterone receptors in tumors decreased by the end of anastrozole therapy. Estrogen receptors- were immunocytochemically revealed in 50% primary breast tumors. Anastrozole slightly decreased, while tamoxifen increased the incidence of these receptors. Interruption of signaling through estrogen receptors and suppression of estrogen biosynthesis had different effects on the receptor status of neoplasms and distribution of estrogen receptors- and -.Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 138, No. 11, pp. 559–562, November, 2004  相似文献   

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An investigation of the cerebral circulation by the thermoelectric method showed that stimulation of the cervical sympathetic nerve leads to considerable changes in the blood supply to the brain. The changes in blood flow are biphasic in character: An initial small increase is followed by a decrease below the original level. Pharmacological analysis with and adrenoblockers showed that the constrictor response of the cerebral vessels is due to excitation of-adrenergic structures and the dilator response to excitation of-adrenergic structures. A possible mechanism of these changes is postulated.Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh.Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 1, pp. 9–12, January, 1976.  相似文献   

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Institute of Medical Genetics, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR, N. P. Bochkov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 6, pp. 735–737, June, 1989.  相似文献   

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The peroxisome proliferator-activated receptor- (PPAR), first identified in 1990 as a member of the nuclear receptor superfamily, has a central role in the regulation of numerous target genes encoding proteins that modulate fatty acid transport and catabolism. PPAR is the molecular target for the widely prescribed lipid-lowering fibrate drugs and the diverse class of chemicals collectively referred to as peroxisome proliferators. The lipid-lowering function of PPAR occurs across a number of mammalian species, thus demonstrating the essential role of this nuclear receptor in lipid homeostasis. In contrast, prolonged administration of PPAR agonists causes hepatocarcinogenesis, specifically in rats and mice, indicating that PPAR also mediates this effect. There is no strong evidence that the low-affinity fibrate ligands are associated with cancer in humans, but it still remains a possibility that chronic activation with high-affinity ligands could be carcinogenic in humans. It is now established that the species difference between rodents and humans in response to peroxisome proliferators is due in part to PPAR. The cascade of molecular events leading to liver cancer in rodents involves hepatocyte proliferation and oxidative stress, but the PPAR target genes that mediate this response are unknown. This review focuses on the current understanding of the role of PPAR in hepatocarcinogenesis and identifies future research directions that should be taken to delineate the mechanisms underlying PPAR agonist-induced hepatocarcinogenesis.  相似文献   

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Summary Neuronal activity was recorded in the medial geniculate body (MGB) of nitrous oxide anaesthetized, paralysed cats in response to click trains. For most cells responding to these stimuli the spike discharges are precisely time locked to individual clicks within the train. The present study has revealed that, apart from the normal locker response being characterized by a monotonic decrease in the entrainment as the frequency of the clicks within the train increases, there is a small population of lockers which show a non-monotonic response to increasing click frequency. 41% of these non-monotonic cells were not at all entrained by the lowest click rates and had time-locked responses for very restricted frequency ranges. These particular non-monotonic lockers were more commonly-found in the posterior part of the pars lateralis and in the suprageniculate nucleus. These cells might be involved in the temporal coding of natural sounds such as animal vocalizations and the cat's purr.Supported by the Swiss National Science Foundation, grant no. 3.509.79  相似文献   

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Laboratory of the Molecular Basis of Pathogenesis of Infectious Diseases, Central Research Institute of Epidemiology, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. I. Pokrovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 105, No. 3, pp. 313–315, March, 1988.  相似文献   

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Cyclic 3,5-AMP (10–6M) activates respiration of the liver mitochondria in all metabolic states and neither changes nor increases the rate of phosphorylation during oxidation of saturating concentrations of isocitrate and succinate. For the effect to be manifested, preincubation of the mitochondria or liver homogenate with cyclic AMP is necessary. The fifth fraction of serum albumin and EDTA do not abolish the effect. Noradrenalin (NA) increases mitochondrial respiration only on incubation with the homogenate. Effects of NA and cyclic AMP do not undergo summation, and the effect of the former is probably mediated by cyclic AMP. The results do not confirm the decisive role of uncoupling of respiration and phosphorylation or accumulation of the oxidation substrate, but instead they suggest activation of mitochondrial enzymes.Department of Biochemistry and Central Research Laboratory, Krasnoyarsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR S. S. Debov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 3, pp. 291–294, March, 1978.  相似文献   

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The effect of class I H-2 antigen expression on the metastatic properties of BL6 melanoma cells was investigated. The BL6-8 clone isolated from the highly metastatic BL6 melanoma did not express H-2K b gene. Following transfection with the H-2Kb gene, BL6-8 cells displayed a low metastatic potential in the immunocompetent as well as immunosuppressed (X-irradiated) or triple-immunodeficient mice with impaired T, B and natural killer (NK) cells function. The expression of H-2Kb gene and the low metastatic ability of transfected BL6 melanoma cells were associated with appearance of cell membrane soybean agglutinin (SBA) and Griffonia simplicifolia 1B4 (GS1B4) lectin-binding carbohydrataes. These alterations in cell surface carbohydrates were found to be a result of reduction in sialylation of SBA binding sites and upregulation of the 1.3 galactosyltransferase (1.3GT) gene. To assess the importance of H-2Kb-induced alterations in cell surface carbohydrates for metastasis formation, BL6-8 melanoma cells were transfected with H-2Kb gene without neor gene cotransfection and selected for adherence to SBA-lectin-conjugated agarose beads. The transfected clones that expressed SBA and GS1B4 lectin-binding carbohydrates were low metastatic. Further analysis of these clones showed that presence of SBA and GS1B4 lectin-binding carbohydrates rather than expression of H-2Kb molecules per se might be responsible for low metastatic potentials of H-2Kb-transfected cells in the immunocompromized mice. Studies of the possible mechanisms responsible for low metastatic ability of H-2Kb-transfected melanoma cells revealed that these cells displayed a reduced ability to adhere to murine pulmonary endothelial cells as well as to laminin and collagen IV. We hypothesized that the observed nonimmunological effects of H-2Kb gene in BL6 melanoma cells is a result of an interaction between the H-2Kb gene and B16 melanoma-specific ecotropic retrovirus. It results in inhibition of this retrovirus production with consecutive alteration in the expression of cellular genes controlling cell surface glycosylation and adhesion properties essential for the metastatic phenotype of BL6 melanoma.  相似文献   

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Summary Immunohistochemical identification of l-antitrypsin (l-AT) and l-antichymotrypsin (l-ACh) in pleomorphic adenomas of salivary glands is reported in order to compare their distribution profiles with those of lysozyme and lactoferrin, already described elsewhere.Normal salivary glands indicated positive l-AT staining in ductal segments and had no l-ACh in any glandular cell. Pleomorphic adenomas displayed moderate positivity to l-AT staining in duct-like, tubular and glandular epithelia which was particularly intense in luminal cells. The limited number of tumour cells which showed duct-like structures with a single cellular layer arrangement, displayed the highest staining to l-ACh. Strongly l-AT positive tumour cells located on the inner side of luminal cavities were also markedly positive to l-ACh. Spindle shaped tumour cells existed outside tubular and ductal structures and were negative to l-AT and l-ACh.Distribution of l-AT in salivary glands was similar to that of lysozyme as is usual in ductal segments or their transformed cells, and occurrence of l-ACh localization rather resembled that of lactoferrin, with occurrence in acinar compartments and changed epithelia within acini.The biological role of a specific immunohistochemical distribution of l-AT and l-ACh in pleomorphic adenomas may be associated with a self regulating mechanism which inhibits degradation by tissue proteinases.  相似文献   

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To determine the relative presence of TCR+ and TCR+ T cells in synovial tissue from patients with various types of inflammatory synovitis and in tissues from patients with a number of chronic T cell-mediated conditions, we stained frozen tissue sections with monoclonal antibodies in indirect immunofluorescence assays. In tissues obtained from patients with chronic T cell-mediated granulomatous conditions (Wegener's granulomatosis, lymphomatoid granulomatosis, granuloma annulare, Langerhan's cells granulomatosis, pigmented villonodular synovitis, Takayasu's arteritis, and talc granulomatosis), the T cells present were predominantly TCR+, without an increased presence of TCR+ cells. In contrast, 6 of 14 (43%) synovia from patients with rheumatoid arthritis (RA) showed increased TCR+ T cells (3–10 cells/hpf). The RA synovia with increased TCR+ cells present had an increased tissue inflammation score compared to RA synovia with few TCR+ cells [18.6±5.8 versus 11.6±4.2 (mean±SE),P<0.05]. In contrast, synovia from patients with osteoarthritis, systemic lupus erythematosus, and trauma did not show an increased presence of TCR+ T cells. Thus, in cellular inflammatory infiltrates the presence of increased TCR cells is not a component of noninfectious granulomatous inflammation but is found in approximately 40% of RA synovia with high levels of inflammation.  相似文献   

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Summary The application of -bungarotoxin onto the chorio-allantoic membrane of chick embryos between the 11th and 18th day of incubation leads to alterations of retinal development. The most significant qualitative change is the appearance of retinal rosettes formed by receptor cells. These rosettes are infoldings of the receptor cell layer. Quantitatively, an enlargement in volume of the receptor and outer nuclear layer can be found together with a simultaneous decrease of the other retinal layers. The toxin seems to suspend the naturally occurring nerve cell death in the receptor cell population.In honour of the 90th birthday of Prof. Dr.Dr. h.c. hermann Voss  相似文献   

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Experiments on rats showed that the level of serotonin activity influences the formation of the shock lung syndrome. In hypoactivity tachyhypopnea is observed and the lung shows a pathomorphological picture characterized by numerous atelectases; in hyperactivity there is a corresponding tachyhyperpnea and a very small number of atelectases.Kazan' Research Institute of Traumatology and Orthopedics. (Presented by Academician of the Academy of Medical Sciences of the USSR P. N. Veselkin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 10, pp. 1181–1183, October, 1976.  相似文献   

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