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91.
Ilhan Kaya Nazife Yigit Mehlika Benli 《African journal of traditional, complementary, and alternative medicines》2008,5(4):363-369
The antimicrobial activities of chloroform, acetone and two different concentrations of methanol extracts of Ocimum basilicum L. were studied. These extracts were tested in vitro against 10 bacteria and 4 yeasts strains by the disc diffusion method. The results indicated that the methanol extracts of O. basilucum exhibited the antimicrobial activity against tested microorganisms. While the chloroform and acetone extracts had no effect, the methanol extracts showed inhibition zones against strains of Pseudomonas aeruginosa, Shigella sp., Listeria monocytogenes, Staphylococcus aureus and two different strains of Escherichia coli. The cells of microorganisms, which were treated and untreated with plant extracts, were observed by using the scanning electron microscope. It was observed that the treated cells were damaged. 相似文献
92.
Piette V Bousquet C Kvedariene V Dhivert-Donnadieu H Crampette L Senac JP Bousquet J Demoly P 《Allergy》2004,59(8):863-868
BACKGROUND: Involvement of paranasal sinuses has been suggested in allergic rhinitis but not clearly demonstrated. AIMS: To investigate the relationship between intermittent allergic rhinitis and computerized tomography (CT). METHODS: Twenty patients with intermittent rhinitis and sensitized to cypress pollens underwent unilateral nasal provocation tests (NPTs) using increasing concentrations of cypress pollens out of the pollen season. Sinus CT-scans were carried out just before a NPT and 24 h later. Nasal lavage was carried out just before a NPT, 30 min after a positive challenge and again 24 h later. Leucotriene C4/D4, intracellular adhesion molecule-1 and eosinophil cationic protein were measured in nasal secretions. RESULTS: Thirteen patients (65%) showed an alteration in their CT-scans after allergen challenge. Ten of them showed sinus changes controlateral to their allergenic provocation. Radiological changes mainly affected the osteomeatal complex and the ethmoid sinuses. Pre-existing abnormalities (13 of 20 cases) mainly concerned the maxillary sinuses. There was no correlation between CT-scan abnormalities and levels of mediators released in nasal secretions. CONCLUSIONS: We have shown that nasal allergen challenge can produce radiological changes in the paranasal sinuses. This mainly concerned the ethmoid sinuses. 相似文献
93.
Sensitivity to tomato and peanut allergens in children monosensitized to grass pollen 总被引:3,自引:2,他引:3
Possible associations between allergy to grass pollen and positive skin tests to food allergens were studied in 102 children monosensitized (as to inhalant allergens) to grass pollen, and in 117 children monosensitized (as to inhalant allergens) to Dermatophagoides. Thirty-two foods were tested by an epicutaneous method. Positive skin tests to food allergens were more frequent in children with allergy to grass pollen (59.8%) than in children with allergy to Dermatophagoides (9.4%). A considerably high frequency of positive reactions to tomato (39.2%), peanut (22,5%), green pea (13.7%), and wheat (11.7%) was observed in children with allergy to grass pollen. Positive skin tests to peanut closely correlated with positive RAST results and nasal provocation tests, whereas in children with skin test positivity to tomato a close correlation with nasal provocation tests but a 45% correlation with a positive RAST result were observed. RAST inhibition experiments were carried out, and the results may suggest the presence of cross-reacting IgE to grass pollen, tomato, and peanut antigens. Clinical implications of these findings are discussed in the light of histories of food hypersensitivity, urticaria-angioedema, and atopic dermatitis in children with allergy to grass pollen. 相似文献
94.
Fluorescencein situ hybridization (FISH) was used to determine the breakpoint of the translocation chromosome in two bread wheat (Triticum aestivum) germplasm lines withThinopyrum intermedium chromatin carrying resistance to either wheat streak mosaic virus (WSMV) or barley yellow dwarf virus (BYDV). In addition, genome-specific random amplified polymorphic DNA (RAPD) markers were used to ascertain the genomic sources of theTh. intermedium chromosomes carrying the WSMV or BYDV resistance. CI17766, a WSMV-resistant wheat germplasm line derived from induced homoeologous pairing by using theph1b mutant, had a translocation chromosome composed of the complete 4AL and about 45% of proximal 4AS from wheat, and the entire 4ES ofTh. intermedium. The BYDV-resistant translocation line, TC14, derived from tissue culture, had a very short distal segment of 7StL fromTh. intermedium terminally attached to 56% of the proximal 7DL. These observations indicate that translocations in these wheat germplasm lines did not involve centromeric breaks and fusion but were a result of homoeologous chromosome recombination.accepted for publication by J. S. (Pat) Heslop-Harrison 相似文献
95.
Immunologic events in pigeon breeders'' disease 总被引:8,自引:0,他引:8
Vernon L. Moore Ph.D. Jordan N. Fink M.D. Joseph J. Barboriak Sc.D. Louis L. Ruff M.D. Donald P. Schlueter M.D. 《The Journal of allergy and clinical immunology》1974,53(6):319-328
The immunologic and physiologic status of a group of symptomatic and asymptomatic pigeon breeders was studied in an attempt to define the immunologic events occurring in pigeon breeders' disease. Antibody activity to antigen(s) present in pigeon dropping extract (PDE) and pigeon serum (PS) was detected in the serum of both symptomatic and asymptomatic breeders. Antibody activity, however, tended to be greater in the symptomatic pigeon breeders. When subjects were challenged with PS via aerosol, serum complement activity became depressed only in asymptomatic patients. Cellular hypersensitivity to antigens present in PDE was detected in vitro in peripheral lymphocyte populations of 4 of 5 symptomatic breeders and in none of the asymptomatic breeders; cellular hypersensitivity to antigens in PS was not demonstrated in any of the individuals tested. These findings indicate that cell-mediated hypersensitivity, as well as humoral immunologic processes, may be involved in the pathogenesis of the hypersensitivity pneumonitis found in pigeon breeders. 相似文献
96.
目的: 探讨缺氧预适应小鼠脑匀浆提取液(HP extract)对PC12细胞缺氧耐受性的影响。方法: 复制小鼠急性重复缺氧模型,制备HP extract。在培养PC12细胞中加入HP extract使其终浓度分别为0.2、0.8、3.2、6.4、12.8 g/L(HP组)。以同浓度正常小鼠脑匀浆提取液(N extract)作为对照组(N组)。缺氧(2%O2) 培养24、48、72 h后, 采用四唑盐(MTT)比色法检测各组细胞活力 (A570值)并检测缺氧24、48、72 h乳酸脱氢酶(LDH)透出率、缺氧24 h早期凋亡率(Annexin V-FITC/PI双染流式细胞仪检测)、缺氧72 h晚期凋亡率(Hoechst33258染色荧光显微镜检测)。结果: HP extract浓度低于6.4 g/L(包括6.4 g/L), 缺氧培养24 h时, HP组A570值显著高于同浓度N组, 其 LDH透出率显著低于同浓度N组。随缺氧时间延长, 高浓度HP extract逐渐失去细胞保护作用。至72 h时浓度高于6.4 g/L(包括6.4 g/L)HP extract有促细胞凋亡作用, 此时HP组A570值显著低于同浓度N组, 其LDH透出率和晚期凋亡率均显著高于同浓度N组。结论: 缺氧预适应小鼠脑匀浆提取液对PC12细胞缺氧耐受性的影响呈浓度依赖性和时间依赖性。 相似文献
97.
98.
Isolation and partial characterization of the tegumental outer membrane of schistosomula of Schistosoma mansoni 总被引:1,自引:0,他引:1
F Levi-Schaffer R Tarrab-Hazdai M D Schryer R Arnon M Smolarsky 《Molecular and biochemical parasitology》1984,13(3):283-300
Separation of the external membranes from freshly converted mechanical schistosomula of Schistosoma mansoni was achieved by osmotic shock under hypertonic conditions, followed by mechanical shearing and ultracentrifugation. Prior to treatment, the schistosomula were surface labeled by introduction of N-DNP-epsilon-aminocaproylphosphatidylethanolamine molecules into their lipid bilayer followed by anti-DNP antibodies and stained with either 125I-protein-A or ferritin labeled secondary anti-DNP antibodies. This label provided a membrane marker by which the purity of the preparation could be assessed at each stage. Fluorescence staining with FITC-conjugated secondary antibodies prior to treatment revealed that the homogeneously stained membrane of the intact schistosomula became swollen and ruptured after the osmotic shock. The isolated membrane pellet was intensely fluorescent. Electron microscopical examination revealed mostly vesicles, some of them with organized multilayer assembly. The vesicles were ferritin labeled, indicating that they originated from the outer surface membrane of the schistosomula. A 100 fold enrichment in the alkaline phosphatase activity and about 300 fold enrichment in acetylcholinesterase activity in the membrane preparations, as compared to the intact schistosomula, was found. The isolated tegument was analyzed by SDS-polyacrylamide gel electrophoresis. The pattern obtained showed three major bands, of molecular weights 69 000, 45 000 and 12 000 alongside with a large number of minor bands. Immunoprecipitation of the isolated 125I-labeled membrane antigens with antisera from chronically infected mice revealed these three major bands together with three other bands of molecular weight 38 000, 23 000 and 16 000. 相似文献
99.
The laminar distribution of cortical connections with the tecto- and cortico-recipient zones in the cat's lateral posterior nucleus 总被引:2,自引:0,他引:2
The anterograde and retrograde transport of wheat germ agglutinin congugated to horseradish peroxidase was used to examine the laminar organization of cortical connections with the two visual zones that comprise the cat's lateral posterior nucleus. Microelectrophoretic deposits of the tracer into the principal tecto-recipient zone in the medial division of the lateral posterior nucleus revealed reciprocal connections with the following cortical fields: areas 19 and 21a, the medial and lateral banks of the middle suprasylvian sulcus, and the dorsal and ventral banks of the lateral suprasylvian sulcus, which correspond to the dorsal lateral suprasylvian and ventral lateral suprasylvian visual areas of Palmer et al. [(1978) Brain Res. 177, 237-256] and an area in the fundus of the posterior suprasylvian sulcus. In each of these cortical areas two distinct populations of cells were labeled, small pyramidal neurons in layer VI and large pyramidal cells in layer V. Overlying these backfilled cells were two bands of anterograde label, a narrow strip in layer I and a wide band centered in layer IV. Deposits of wheat germ agglutinin conjugated to horseradish peroxidase confined to the striate-recipient zone in the lateral portion of the lateral posterior nucleus resulted in cortical label in areas 17, 18, 19, 20a and b, 21a, the medial and lateral banks of the middle suprasylvian sulcus, the posterior suprasylvian sulcus and in the fundus of the splenial sulcus. In all cortical areas other than 17 and 18, the laminar distribution of label was the same as that found after deposits of the tracer into the medial division of the lateral posterior nucleus. In contrast, areas 17 and 18 contained backfilled cells that were confined to layer V and anterograde label that was restricted to layer I. These findings indicate that the cortical areas that receive a direct projection from the A laminae of the dorsal lateral geniculate nucleus maintain a distinct laminar organization of reciprocal connections with the extrageniculate visual thalamus. Conversely, all other visual areas of the cortex share a common pattern of reciprocal connections with both the tecto- and striate-recipient zones of the lateral posterior nucleus. 相似文献
100.
Objective: To investigate whether cockroach allergen extract can stimulate Protease-activated receptor 2 (PAR-2) expressed in mouse lung fibroblast.Materials: We established an immortalized lung fibroblast cell line, DM5, from PAR-2 deficient mice. By stable transfection with either an empty vector (DM5/EV) or an expression vector encoding mouse PAR-2 cDNA (DM5/Par2), a pair of lung fibroblast cell lines with or without functional PAR-2 expression were prepared.Treatment: The cells were exposed to cockroach allergen extract {up to 800 protein nitrogen unit (PNU)/ml}, trypsin (up to 100 nM), SLIGRL agonist peptide (up to 500 M), and trans-cinnamoyl-LIGRO agonist peptide (up to 400 M).Methods: The cells were loaded with Fluo-3 calcium indicator and mobilization of intracellular calcium with the stimuli was monitored by a fluorometric plate reader. Extracellular signal-regulated kinase (ERK) phosphorylation was examined by Western blot analysis using an anti-phospho ERK antibody.Results: The cockroach extract induced intracellular calcium transients in a concentration dependent manner in DM5/Par2 but not in DM5/EV. The activity was abolished when the cockroach extract was heat denatured or pre-incubated with PMSF (phenylmethanesulfonyl fluoride) prior to the assay. Concomitantly, ERK phosphorylation was seen in DM5/Par2 with the cockroach extract but not with a heat-denatured extract. The responses were sensitive to an inositol-1,4,5 triphosphate antagonist (2-APB) indicating that calcium was mobilized from intracellular store.Conclusions: Cockroach allergen extract can activate PAR-2 and thereby stimulate mouse lung fibroblasts likely through protease(s). The present study proposes a potential mechanism for cockroach antigens, similar to house dust mite antigens, in the etiology of respiratory diseases.Received 29 February 2004; returned for revision 12 April 2004; accepted by M. Katori 22 April 2004 相似文献