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1.
复方溴氯海因消毒剂性能的试验观察   总被引:1,自引:1,他引:1  
目的 研究复方溴氯海因消毒剂的性能。 方法 在实验室我们分别进行悬液定量杀灭试验、稳定性试验、毒性试验。 结果 复方溴氯海因消毒剂为含溴氯海因的片剂 ,含有效氯 471g/kg ,以含复方溴氯海因消毒剂 1:2 0 0 0(g/ml)的稀释液对大肠杆菌、金黄色葡萄球菌分别作用 5、10min的杀灭对数值各次均大于 5 .0 0。含复方溴氯海因消毒剂 1:2 0 0 (g/ml)的稀释液对白色念珠菌作用 10min的杀灭对数值各次均大于 4.0 0。现场试验表明 ,消毒效果好。该片剂置 3 7℃温箱 90d后 ,其有效氯含量下降率 1.74%。毒性试验显示 ,急性经口毒性试验表明该片剂属实际无毒 ;无刺激性 ;微核试验结果为阴性 ;2 0 0mg/kg·bw为最大未观察到有害作用剂量 ,10 0 0mg/kg·bw为最小观察到有害作用剂量。 结论 复方溴氯海因消毒剂属于一类杀菌广谱、高效、无毒、稳定性好的消毒剂。  相似文献   
2.
Ten South African Commiphora (Burseraceae) species were investigated to validate their use in traditional healing rites. The leaf and stem extracts of each species were analysed for the anti-oxidant (ABTS and DPPH assays), antimicrobial (MIC and death kinetic assays), anti-inflammatory (5-LOX assay), anticancer (SRB assay) properties, as well as the cytotoxic effects (tetrazolium-based assay). The best anti-oxidant activity (ABTS assay) was observed for the stem extracts of Commiphora tenuipetiolata IC(50)=5.10 microg/ml), Commiphora neglecta (IC(50)=7.28 microg/ml) and Commiphora mollis (IC(50)=8.82 microg/ml). Extracts generally exhibited poor anti-oxidant activity in the DPPH assay, with the exception of Commiphora schimperi (stem), Commiphora neglecta (stem), Commiphora tenuipetiolata (stem and leaf), and Commiphora edulis (stem), with IC(50) values ranging between 7.31 and 10.81 microg/ml. The stem extracts exhibited moderate to good 5-LOX inhibitory activity with Commiphora pyracanthoides (stem) displaying the greatest inhibitory effect (IC(50)=27.86+/-4.45 microg/ml). For the antimicrobial (MIC) assay, a greater selectivity was exhibited by the extracts against the Gram-positive bacteria (0.01-8.00 mg/ml) and the yeasts (0.25-8.00 mg/ml) than against the Gram-negative bacteria (1.00-8.00 mg/ml). Using death kinetic studies (time-kill studies), the rate at which Commiphora marlothii (stem) kills Staphylococcus aureus over a 24h period was determined. Mostly, a concentration-dependent antibacterial activity was observed beginning after ca. 30 min. All concentrations exhibited antibacterial activity, with complete bactericidal effect achieved by the 24(th) hour. The most active Commiphora species against the HT-29 cells (SRB anticancer assay) were Commiphora glandulosa (leaf and stem) and Commiphora marlothii (leaf). The MCF-7 cells (SRB anticancer assay) exhibited the highest sensitivity to indigenous Commiphora species, with Commiphora edulis (leaf and stem), Commiphora glandulosa (leaf and stem), Commiphora marlothii (leaf), Commiphora pyracanthoides (leaf and stem), Commiphora schimperi (stem), and Commiphora viminea (stem) all possessing a percentage inhibition greater than 80% at 100 microg/ml. Commiphora glandulosa (leaf and stem) and Commiphora pyracanthoides (leaf and stem) were the two most active species against the SF-268 cells (SRB anticancer assay), with IC(50) values ranging between 68.55+/-2.01 and 71.45+/-1.24 microg/ml. The majority of the Commiphora extracts were largely non-cytotoxic against Graham human kidney epithelial cells when investigated in the MTT assay.  相似文献   
3.
Microbial detoxification of deoxynivalenol (DON) represents a new approach to treating DON-contaminated grains. A bacterium Devosia mutans 17-2-E-8 was capable of completely transforming DON into a major product 3-epi-DON and a minor product 3-keto-DON. Evaluation of toxicities of these DON-transformation products is an important part of hazard characterization prior to commercialization of the biotransformation application. Cytotoxicities of the products were demonstrated by two assays: a MTT bioassay assessing cell viability and a BrdU assay assessing DNA synthesis. Compared with DON, the IC50 values of 3-epi-DON and 3-keto-DON were respectively 357 and 3.03 times higher in the MTT bioassay, and were respectively 1181 and 4.54 times higher in the BrdU bioassay. Toxicological effects of 14-day oral exposure of the B6C3F1 mouse to DON and 3-epi-DON were also investigated. Overall, there were no differences between the control (free of toxin) and the 25 mg/kg bw/day or 100 mg/kg bw/day 3-epi-DON treatments in body and organ weights, hematology and organ histopathology. However, in mice exposed to DON (2 mg/kg bw/day), white blood cell numbers and serum immunoglobulin levels were altered relative to controls, and lesions were observed in adrenals, thymus, stomach, spleen and colon. Taken together, in vitro and in vivo studies indicate that 3-epi-DON is substantially less toxic than DON.  相似文献   
4.
Helin T  Haahtela S  Haahtela T 《Allergy》2002,57(3):243-246
BACKGROUND: Oral probiotic bacteriotherapy with Lactobacillus rhamnosus has given promising results in small children with food allergy. We studied the effects of similar therapy in teenagers and young adults, who were allergic to birch pollen and apple food and had intermittent symptoms of atopic allergy and/or mild asthma. METHODS: We conducted a double-blind, placebo-controlled study, in which respiratory and eye symptoms and use of medications in two groups were compared. Open oral challenge tests with a slice of apple were performed trice: before, during and after the birch-pollen season. There were 18 patients in each group. They used Lactobacillus rhamnosus for 5.5 months; 2.5 months before the pollen season, 1 month during the season (May), and 2 months after. RESULTS: The results were negative. The treatment did not alleviate the symptoms of the patients or reduce their use of medication during the birch-pollen season or the subsequent 2 months. The treatment did not significantly affect the symptoms caused by apple in the oral challenge tests. CONCLUSIONS: We found no indication of a beneficial treatment effect in our patients. As the number of patients was relatively small, conclusions should be drawn with caution.  相似文献   
5.
Presence of Propionibacterium acnes in blood components   总被引:2,自引:0,他引:2  
Kunishima S  Inoue C  Kamiya T  Ozawa K 《Transfusion》2001,41(9):1126-1129
BACKGROUND: Sterility testing, as part of the QC of blood components at the Japanese Red Cross Aichi Blood Center between April 1998 and March 2000, showed that 10 of 5568 tested blood components (0.18%), all of which were RBC concentrates, were contaminated with bacteria. Nine isolates were Propionibacterium acnes and one was Staphylococcus capitis. STUDY DESIGN AND METHODS: To investigate the molecular relatedness of eight available P. acnes isolates, 16S rRNA gene analysis and random amplified polymorphic DNA (RAPD) analysis were performed. RESULTS: DNA sequencing analysis of the 16S rRNA gene showed that five isolates were identified as distinct strains and that three had identical sequences. RAPD analysis in the latter three isolates showed that two exhibited indistinguishable banding patterns that differed from that of the third isolate. CONCLUSION: P. acnes was the most frequent contaminant of blood components, and six of eight isolates were molecularly unrelated. Further studies are necessary to investigate the precise mechanisms of contamination.  相似文献   
6.
We evaluated whether KIOM-79, a mixture of extracts obtained from Puerariae lobata, Magnolia officinalis, Glycyrrhiza uralensis and Euphorbia pekinensis, could inhibit vascular endothelial growth factor (VEGF) expression in human retinal pigment epithelial (RPE) cells cultured under high glucose (HG, 25mM) or S100b (a specific ligand of the receptor for advance glycation end products (RAGE), 5microg/ml). In this study, the effect of KIOM-79 on HG or S100b-induced VEGF expression was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, RT-PCR, ELISA, and Western blot on human RPE cells. The MTT assay (p<0.01) revealed that KIOM-79 (up to 1mg/ml) had no effect on cell growth. HG or S100b induced an increase in expression of VEGF at both mRNA and protein levels (p<0.05; p<0.01 versus control). The increase in VEGF expression by HG or S100b was dose- and time-dependently prevented by KIOM-79 (p<0.05 versus 25mM glucose; p<0.01 versus S100b). Also, KIOM-79 inhibited protein kinase C (PKC)-alpha/beta(alpha) and p38 mitogen-activated protein kinase (MAPK) activation. Our results demonstrate that KIOM-79 can inhibit VEGF expression via inhibition of the MAPK and PKC pathway.  相似文献   
7.

Background

This study explores the potential diagnostic utility of soluble Human Leukocyte Antigen (sHLA) molecules differentially released by lung adenocarcinoma and benign lung lesions.

Methods

Conditioned media from the NSCLC cell lines H358 and H1703 were immunoblotted for soluble isoforms of major histocompatibility complex (MHC) class I (ABC) and II (DRB1, DMB, and DQ) antigens. Sera from 25 patients with benign and 25 patients with malignant lesions were similarly evaluated to appraise the potential diagnostic value.

Results

Higher concentrations of soluble HLA class I molecules were observed in conditioned medium for the highly-invasive H1703 cell line, relative to the more indolent H358 cells. Evaluation of these markers against a cohort of 50 cases demonstrated that patients with malignant lesions possess higher levels of HLA class I and II molecules relative to those with benign lesions (p?<?0.05), with exception to the primary isoform, DQA1, which was suppressed in malignancies. An analysis of biomarker performance via ROC analysis revealed promising performance (AUC?>?0.75) for DMB and the 26?kDa isoform of DQ in distinguishing lesion pathology.

Conclusions

Soluble HLA molecules may have diagnostic value for early-stage NSCLC. Validation studies are currently underway using sera from a lung cancer screening cohort.  相似文献   
8.
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9.
BACKGROUND & AIMS : LL-37/human cationic antimicrobial peptide 18 (hCAP18) is a human cathelicidin with broad-spectrum antimicrobial, lipopolysaccharide binding, and chemotactic activities. This study examined the role of LL-37/hCAP18 in gastric innate immune defense by characterizing its constitutive and regulated expression by human gastric mucosa and its bactericidal activity against the gastric pathogen Helicobacter pylori. METHODS : LL-37/hCAP18 messenger RNA expression in normal and H. pylori -infected gastric mucosa and gastric epithelial cells was determined by in situ hybridization, real-time polymerase chain reaction, immunostaining, and immunoblot analysis. Bactericidal activity was measured by using a colony-forming unit assay. RESULTS : LL-37/hCAP18 messenger RNA and protein were expressed in a distinct distribution by surface epithelial cells as well as chief and parietal cells in the fundic glands of normal gastric mucosa. LL-37/hCAP18 was significantly increased in the epithelium and gastric secretions of H. pylori -infected patients, but not in individuals with non-H. pylori -induced gastric inflammation. Infection of cultured gastric epithelial cells with a wild-type but not an isogenic Delta cagE mutant strain of H. pylori increased LL-37/hCAP18 expression, indicating that H. pylori -induced regulation of LL-37/hCAP18 production required an intact type IV secretion system. LL-37, the C-terminal peptide of LL-37/hCAP18, alone or in synergy with human beta-defensin 1, was bactericidal for several H. pylori strains. CONCLUSIONS : These data indicate that H. pylori up-regulates production of LL-37/hCAP18 by gastric epithelium and suggest this cathelicidin contributes to determining the balance between host mucosal defense and H. pylori survival mechanisms that govern chronic infection with this gastric pathogen.  相似文献   
10.
本文研究了产青霉素酰化酶的大肠杆菌ATCC11105在PE620000-DextranT70两水相系统中的动力学行为,并与在磷酸盐缓冲液中的动力学行为进行了对照。产青霉素酰化酶的菌体在两水相体系中的K_m值为4.35mmol/L,最适pH值为8.0,最适温度为55℃,最稳定pH值为6.0~7.0,最稳定温度为30℃;在磷酸盐缓冲液中K_m值为7.20mmol/L,最适pH值为8.0,最适温度为65℃,最稳定pH值为8.0,最稳定温度为35℃。  相似文献   
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