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1.
The radioprotective effect of bael (Aegle marmelos, AME) extract was studied in Swiss albino mice against radiation-induced changes in the peripheral blood, spleen colony forming units, and intestinal mucosa. The mice were treated with 250 mg/kg body weight of AME orally once daily for five consecutive days before exposure to an acute dose of 7 Gy of gamma radiation after the last administration. The peripheral blood was collected and evaluated for red blood cell (RBC), hemoglobin, total leukocyte count (TLC), and lymphocyte count on days one and seven postirradiation. The nucleated bone marrow cells were isolated and tested for colony-forming units (CFUs) in spleen at days one and seven. AME protected mice against the radiation-induced decline in hemoglobin, total leukocyte, and lymphocytes counts and the clonogenicity of hemopoietic progenitor cells assessed by the exogenous spleen colony-forming assay. Irradiation of mice caused a significant decline in the villus height and crypt number with an increase in goblet and dead cells in the small intestine, where the maximum changes were observed on day one postirradiation, indicating a severe damage, and signs of recovery at day seven postirradiation. Treatment of mice with AME before irradiation elevated the peripheral cell count as well as villus height and the crypt number accompanied by a decline in goblet and dead cells when compared with the irradiation control. The recovery and regeneration were faster in AME pretreated animals than the irradiation alone. AME pretreatment significantly decreased lipid peroxidation accompanied by a significant elevation in the GSH concentration in the mouse intestine. The data clearly indicate that the AME significantly reduced the deleterious effect of radiation in the intestine and bone marrow of mouse and could be a useful agent in reducing the side effects of therapeutic radiation.  相似文献   

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The radioprotective effect of a hydroalcoholic extract of Aegle marmelos (AME) was evaluated in cultured human peripheral blood lymphocytes (HPBLs) by the micronucleus assay. The optimum protective dose of the extract was selected by treating HPBLs with 1.25, 2.5, 5, 6.25, 10, 20, 40, 60, 80 and 100 microg/ml AME before exposure to 3 Gy gamma-radiation and then evaluating the micronucleus frequency in cytokinesis blocked HPBLs. Treatment of HPBLs with different doses of AME reduced the frequency of radiation-induced micronuclei significantly, with the greatest reduction in micronucleus induction being observed for 5 microg/ml AME. Therefore, this dose of AME was considered as the optimum dose for radioprotection and further studies were carried out treating the HPBLs with 5 microg/ml AME before exposure to different doses (0, 0.5, 1, 2, 3 and 4 Gy) of gamma-radiation. The irradiation of HPBLs with different doses of gamma-radiation caused a dose-dependent increase in the frequency of lymphocytes bearing one, two and multiple micronuclei, while treatment of HPBLs with 5 microg/ml AME significantly reduced the frequency of lymphocytes bearing one, two and multiple micronuclei when compared with the irradiated control. The dose-response relationship for both groups was linear. To understand the mechanism of action of AME separate experiments were conducted to evaluate the free radical scavenging of OH, O2(-), DPPH, ABTS(+) and NO in vitro. AME was found to inhibit free radicals in a dose-dependent manner up to a dose of 200 microg/ml for the majority of radicals and plateaued thereafter. Our study demonstrates that AME at 5 microg/ml protected HPBLs against radiation-induced DNA damage and genomic instability and its radioprotective activity may be by scavenging of radiation-induced free radicals and increased oxidant status.  相似文献   

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This study assessed the chemopreventive potential of the Aegle marmelos plant on mouse skin tumorigenesis initiated by 7,12-dimethylbenz(a)anthracene (DMBA) and promoted by croton oil. A significant reduction in tumor incidence, tumor burden, tumor multiplicity, and the cumulative number of papillomas, along with a significant increase in the average latent period, was recorded in mice treated orally with A. marmelos extract (AME) at peri - and post-initiation phases (i.e., 7 days before DMBA application and continued until the end of the experiment) of papillomagenesis as compared with the carcinogen-treated controls. Furthermore, a significant increase in catalase activity, reduced glutathione and total proteins, and a depleted level of lipid peroxidation were observed in liver and skin of AME-treated animals as compared with the carcinogen-treated controls. Thus, the oral administration of AME, at a dose of 50 mg/kg body wt per day per animal, was found to be significantly effective in reducing skin tumors against chemical carcinogenesis in mice.  相似文献   

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This study describes the radioprotective ability of a hydrolysate prepared using an enzyme-acid hydrolysis method from the green mussel Perna viridis in terms of its ability to prevent radiation-induced damage in plasmid DNA, cell death, reactive oxygen species (ROS) formation, and DNA damage in mice lymphocytes. The mussel hydrolysate (MH) present during irradiation showed significant protection from gamma-radiation-induced strand breaks in plasmid DNA as evaluated by gel electrophoresis. Viability studies by trypan blue dye exclusion and MTT assay showed that preincubation of mice splenic lymphocytes with MH protected them from gamma-radiation-mediated killing. Moreover, the presence of MH during irradiation of isolated mice lymphocytes significantly decreased the DNA damage, as measured by comet assay. Measurement of intracellular ROS by dichlorofluorescein fluorescence revealed that the presence of MH effectively reduced the ROS generated in lymphocytes by both chemical method and gamma-irradiation. Prevention of DNA damage both in plasmid and lymphocytes and cell death in lymphocytes appears correlated with reduction of oxidatively generated free radicals. It is concluded that protection against radiation-induced cell death and DNA damage by MH was attributable to reduction of reactive free radical species generated by gamma-radiation.  相似文献   

5.
H Bazin  B Platteau 《Immunology》1976,30(5):679-684
Reaginic antibody synthesis following parenteral and/or oral administration of ovalbumin and Bordetella pertussis organisms as adjuvant has been evaluated in LOU/M/Wsl inbred rats. These rats are able to produce high reaginic antibody serum levels after intraperitoneal injection of this antigen. Primary oral administration of ovalbumin doses between 10 and 100 mg with Bordetella pertussis organisms given as adjuvant by the intraperitoneal or the oral route led to characteristic reagnic responses. Secondary reaginic responses were obtained by oral administration of ovalbumin without any adjuvant in animals sensitized by the oral or the intraperitoneal route. A hundred micrograms of ovalbumin was enough to induce reaginic responses but more constant and higher reaginic levels were obtained with a 50 mg dose in the experimental model employed.  相似文献   

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In vivo administration of bacterial lipopolysaccharide to mice induced DNA fragmentation in the thymus. Fragmented DNA was confirmed by agarose gel electrophoresis and laser flow cytometry. DNA fragmentation was predominantly detected in the thymus of young mice, while it was undetectable in the spleen, bone marrow, and lymph nodes. DNA fragmentation in the thymus was roughly dependent on the dose of lipopolysaccharide injected and reached the peak about 18 h after the injection. The addition of lipopolysaccharide to in vitro cultures of thymocytes did not cause DNA fragmentation, suggesting that lipopolysaccharide was unable to induce apoptosis of thymocytes directly. The injection of lipopolysaccharide induced no significant DNA fragmentation in adrenalectomized mice. The injection of anti-tumor necrosis factor alpha antibody together with lipopolysaccharide partially inhibited the appearance of DNA fragmentation in the thymus. On the basis of the fact that DNA fragmentation is one of the characteristics typical in apoptotic cell death, it was suggested that lipopolysaccharide could induce apoptosis in the mouse thymus in vivo. This apoptosis in the thymus might be mediated mainly by the adrenal hormones, but it is likely that tumor necrosis factor alpha might also participate in it.  相似文献   

8.
初步研究了青葙子和野生紫苏子的化学成分和营养价值。分析结果表明青葙子和野生紫苏子中氨基酸种类比较齐全,必需氨基酸含量较高,分别达42.85%和32.60%。两种种子均含有丰富的脂肪油,其脂肪油的主要成分为:棕榈酸、硬脂酸、油酸、亚油酸、亚麻酸等,不饱和脂肪酸的含量分别为79.276%和91.020%。两种子亦含有种类较齐全的矿质元素。其种子和种子油具有较高的营养价值,值得进一步开发利用。  相似文献   

9.
Cysteine proteinase activities were examined in lesion amastigotes as well as in stationary-phase promastigotes ofLeishmania (L.) mexicana andLeishmania (L.) amazonensis isolates. Enzyme detection in gelatin gels revealed that amastigotes of threeL. (L.) mexicana isolates (M379, IOC-0561, and IP) shared similar proteinases, including the multiple low-molecular-weight (25–35 kDa) cysteine proteinases. High cysteine proteinase activity was also observed inL. (L.) amazonensis amastigotes, but the banding profile was different in two of the isolates examined. Promastigotes displayed fewer low-molecular-weight proteinase bands, and these were much less intense as compared with those of lesion amastigotes. Independently of theLeishmania isolates and developmental stages examined, incubation of the parasites for 2 h with 0.2 M radioiodinatedN-benzyloxycarbonyl-tyrosyl-alanyl diazomethane (Z-Tyr[125I]-AlaCHN2) markedly and selectively labeled bands comigrating with the 28- and 31-kDa cysteine proteinases. Under reducing conditions, labeling was associated with four similar polypeptides (29–34 kDa), which were also detected when incubation with Z-Tyr[125I]-AlaCHN2 was carried out after cell lysis. Labeling was completely abolished if lysates were first incubated with 20 M E-64 and then exposed to the125I-tagged inhibitor, thus confirming the specificity of the compound toward cysteine proteinases.  相似文献   

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Summary Light and transmission electron microscopy of the strobila of a large old Ligula intestinalis plerocercoid has revealed microcrystals with a morphology similar to that of microapatite crystals from vertebrates. Analysis of the microcrystals with EMMA-4 showed them to contain calcium and phosphorus. The tissue in the immediate vicinity of the microcrystals shows signs of necrosis while further away it is histologically normal.Some equipment used in this investigation was provided by the Royal Society and the Wellcome Trust.  相似文献   

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This is the first demonstration of a role for type II collagen in pristane-induced arthritis. Pretreatment with soluble type II collagen either lowers or raises the subsequent incidence and severity of pristane-induced arthritis. These effects are dependent upon both the dose and route of administration of the soluble type II collagen. Increasing doses of orally administered type II collagen lowered both the incidence and severity of pristane-induced arthritis. Conversely, increasing doses of intraperitoneally administered type II collagen increased both the incidence and severity of arthritis. This exacerbation of pristane-induced arthritis was accompanied by elevated B- and T-cell responses to type II collagen. These findings highlight the importance of the site at which antigen is encountered in influencing subsequent immune responses and extend the observations of the use of orally administered antigens to ameliorate experimental autoimmunity.  相似文献   

15.
A gene encoding the full-size botulinum neurotoxin serotype C was reconstructed in vector pQE-30 and expressed at high levels in Escherichia coli. Three amino acid mutations (H229-->G, E230-->T, and H233-->N) were generated in the zinc-binding motif, resulting in complete detoxification of the modified recombinant holotoxin. The PCR-amplified wild-type light chain of botulinum neurotoxin serotype C was also expressed in E. coli and used as a control in all experiments. Modified recombinant holotoxin and light chain contained a histidine affinity tag at the amino terminus, which was used for detection and purification. Recombinant proteins were purified on nickel affinity resin and analyzed by Western blotting with the anti-histidine tag and anti-neurotoxin C antibodies. The results indicated that the 150-kDa molecule of modified recombinant holotoxin and the 50-kDa recombinant light chain were synthesized without degradation; however, E. coli did not provide for efficient nicking of modified recombinant toxin. Modified recombinant holotoxin was not toxic to mice, had no effect on nerve-evoked muscle twitch in vitro, and was not able to cleave syntaxin in crude synaptosome preparations. The recombinant light chain was also nontoxic in vivo, had no effect on evoked muscle twitch, but was able to cleave syntaxin. Modified recombinant neurotoxin and light chain were administered to animals either orally or subcutaneously. Both oral administration and subcutaneous administration of modified recombinant neurotoxin evoked high levels of serum antibodies and protective immunity. Oral administration of recombinant light chain evoked no systemic response, whereas subcutaneous administration evoked antibody production and immunity.  相似文献   

16.
BACKGROUND: Date fruit and pollen antigens share a number of cross-reactive epitopes. Date pollen has been shown to cross-react with antigens from Artemisia, cultivated rye (Secale cereale), Timothy grass (Phleum pratense), Sydney golden wattle (Acacia longifolia) and Bermuda grass (Cynodon dactylon) pollen. The present study was carried out to examine any cross-reactivities between date palm polypeptides and antigens of some common foods and vegetables that have been implicated in the oral allergy syndrome (OAS). Because most of such cross-reactivities in other allergens are attributable to the presence of carbohydrate chains and profilin, their role was also investigated. METHODS: Fresh extracts of 20 common fruits and vegetables were prepared. Putative date profilins were isolated by affinity chromatography using a poly L-proline column. Date fruit extracts were digested by various endoglycosidases and the immunoglobulin (Ig)E binding of the postdigest products was assessed in immunoblots. Rabbit antisera to whole date fruit extracts, Timothy grass profilin and putative date profilins, as well as human sera from date sensitive individuals were used in immunoblotting, ELISA and in inhibition experiments. RESULTS: IgG, ELISA and immunoblot results with the different rabbit antisera and date-sensitive atopic sera showed several antigenic cross-reactivities and similar cross-reactivities were seen with birch, date and timothy grass profilins. IgE, ELISA and immunoblot experiments with pooled date sensitive human sera showed a range of cross-reactivities with some food extracts. A number of the IgE cross-reactivities could be inhibited after preabsorption of pooled sera with date extracts. Sixty-six percent of individual date hypersensitive human sera bound IgE in putative date fruit profilin and their pooled sera bound IgE in birch pollen profilin. IgE-binding of the endoglycosidase digested date fruit extracts to atopic serum pool was restricted to only a very low molecular weight band of 6.5-8 kDa. CONCLUSION: These results indicate that date palm polypeptides share cross-reactive IgG and IgE epitopes with a number of foods implicated in the oral allergy syndrome, bind to birch and Timothy grass profilins and bind IgE through glycosyl residues. The clinical relevance of these cross-reactivities needs to be further elucidated.  相似文献   

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Zusammenfassung Es wird das klinische und pathologisch-anatomische Bild einer schweren Sarcoptesräude bei Flachlandtapiren (Tapirus terrestris) beschrieben. Der Erreger wird auf Grund seiner morphologischen und biologischen Eigenschaften einer neuen Art, Sarcoptes tapiri zugeordnet.
Sarcoptic mange (Sarcoptes tapiri nov. spec.) of tapirs (Tapirus terrestris L.)
Summary The clinical and patho-anatomical type of a severe sarcoptic manage of tapirs (Tapirus terrestris) is being described. The sarcoptic mite is classified as a new species, Sarcoptes tapiri, owing to its morphological and biological qualities.
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The carbonic anhydrase inhibitors, acetazolamide and MK-0927, were given by oral route to male Sprague-Dawley rats at 200 mg/kg/day and 25 mg/kg/day, respectively, for up to 4 weeks. Sequential necropsies were performed and urinary bladders were examined by light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Similar urinary bladder changes were seen with both compounds. SEM evidenced slight multifocal urothelial changes consisting of cell swelling, dissociation, degeneration, and exfoliation after 3 and 5 days of treatment. After 2 and 4 weeks of treatment, elevated or leafy microridges on the luminal cell surfaces were seen together with foci of swollen cells. After a 2-month-recovery-period, the urothelial surfaces were normal. LM and TEM showed multifocal vacuolation of the urothelium associated with inflammation of the underlying lamina propria after 3 and 5 days of treatment. Cellular hypertrophy and hyperplasia of the transitional epithelium was seen after a 5-day treatment, persisted without increasing severity after 2 and 4 weeks of treatment, and totally regressed after the recovery period. It was concluded that, in the rat urinary bladder, oral administration of acetazolamide and MK-0927 induced early degeneration and inflammation followed by epithelial regeneration, resulting in a reversible hyperplasia of the transitional epithelium.  相似文献   

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