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Heat shock proteins (HSP) act as immunological target structures either by themselves because of an unusual expression pattern, or they are carrier proteins for immunogenic peptides. A three-allele polymorphism of HSP70-1 promoter region was analysed in random patients with pulmonary tuberculosis (PTB), or with tuberculoid (TT) leprosy and healthy controls from North India. HSP70-1A and HSP70-1C occurred more frequently (> 60%) while HSP70-1B occurred infrequently in this population. Only HSP70-1A allele was significantly increased in TT leprosy as compared to healthy controls (91.8% Vs 71.1%, Pc < 0.03, RR = 4.58). Although a strong association of HLA-DR15 was observed with both of these patient groups in earlier studies, no correlation was found between HSP70-1 promoter alleles with any of the HLA allotypes. Amongst six possible genotype combinations of HSP70-1 promoter allele, only four (A/A, A/B, A/C, C/C) were encountered in Asian Indians. A significant increase of HSP70-1 A/C genotype was observed among DR15 negative PTB patients as compared to DR15 negative controls (87.5% Vs 35.7%, X2 = 8.6, Pc < 0.02) giving highest relative risk of 12.6. These findings suggest that HSP70-1 genes may play a secondary role to HLA-DR in governing susceptibility to mycobacterial infectious diseases. 相似文献
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Species differences in the occurrence of copper-metallothionein in the particulate fractions of the liver of copper-loaded animals. 总被引:1,自引:1,他引:0 下载免费PDF全文
Large amounts of Cu-metallothionein were obtained by 2-mercaptoethanol and sodium dodecyl sulphate extractions of the particulate fractions of the liver of pigs given high-Cu2+ diets or rats injected with Cu2+. Three isoproteins were purified from pig liver and characterized on the basis of their physicochemical properties, metal content and amino acid composition. No such pool of Cu-metallothionein was present in the liver of Cu2+-loaded sheep or of rats given Cu2+-supplemented diets. 相似文献
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Widespread use of metals in industrial activities has enhanced the occupational exposure to toxic metals as well as the health risks of metal hazards to humans. Elemental analysis in human tissues is the most common application of biological monitoring for screening, diagnosis and assessment of such exposures and risk. Among various biopsy materials, blood, hair, nail, teeth and body fluids may be used as bioindicators for this purpose. The present paper deals with the determination of Pb, Cr, Ni, Mn, Fe, Cu and Zn elemental concentration in workers exposed to these metals at workplace by atomic absorption spectrophotometry, with adequate quality control measures using hair as biopsy material. The study group includes the male workers such as welders, foundry man, fitter, hammer man, machine man, cupola man etc., besides office workers of locomotive workshop in Ajmer and surrounding areas exposed to different metals. Age and sex matched controls of persons working in the same area of work in offices etc. and not exposed to metal pollution were selected for valid comparison. It is proposed to validate the use of hair as a biological marker for assessing metal body burden of workers. In our study significant correlations have been found between skin disease and Cr, Mn, Fe, Cu; chest pain and Pb; hypertension and Cu, Mn; mental stress and Mn, Ni, Cu, Zn; liver problem and Ni; indigestion and Cr; Ni, diabetes and Cr, Mn, Ni; tuberculosis and Zn; breathing trouble and Cr, Mn, Fe, Ni, Zn. The advantages of choosing hair as a biopsy material are also given. 相似文献
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T. N. Khoshoo R. C. Mehra K. Bose 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1969,39(3):133-140
Summary
Ruellia tweediana and R. tuberosa are large flowered chasmogamous diploids (n=17) with normal meiosis and fertility. F
1 hybrids, successful in only one direction (R. tweediana x R. tuberosa), are vegetatively vigorous and possess 17 often heteromorphic bivalents with high degree of segregational irregularities. It is exclusively cleistogamous and completely pollen and seed sterile. Like F
1, the artificial amphidiploid (n=34) is also cleistogamous but shows preferential chromosome pairing with complete restoration of fertility. The parental chromosomes are sufficiently differentiated and cleistogamy is either genie or due to gene-cytoplasm interaction but sterility is entirely chromosomal. All floral parts excepting calyx are highly deformed. Such a deformity is associated with sterility in the F
1 but with fertility in the amphidiploid. This is perhaps the first case of origin by hybridization of a true breeding and fully fertile cleistogamous taxon from two chasmogamous species. It also shows the extent and nature of change in breeding system brought about by hybridization and/or polyploidy.The chromosome numbers in the six, out of 16, obligate cleistogamous taxa (Table 4) show that they are high polyploids. Perhaps their origin has been in the same manner as in the present case.
Zusammenfassung Ruellia tweediana und R. tuberosa sind großblütige, chasmogame Diploide (n=17) mit normaler Meiosis und Fertilität. Die F 1-Hybriden, die nur in einer Richtung gelingen (R. tweediana x R. tuberosa), sind vegetativ kräftig und besitzen häufig 17 heteromorphe Bivalente mit einem hohen Anteil an Spaltungsunregelmäßigkeiten. Die Hybride ist ausschließlich kleistogam und vollkommen pollen- und samensteril. Wie die F 1 ist auch die künstlich hergestellte Amphidiploide (n=34) kleistogam und zeigt eine präferentielle Chromosomenpaarung mit völliger Wiederherstellung der Fertilität. Die elterlichen Chromosomen sind genügend differenziert. Die Kleistogamie ist entweder genisch bedingt oder auf eine Gen-Cytoplasma-Interaktion zurückzuführen, die Sterilität ist ausschließlich durch die Chromosomen verursacht. Alle Teile der Blüte mit Ausnahme der Calyx sind stark deformiert. Bei der F 1 ist diese Deformation mit Sterilität verbunden, die amphidiploide Form ist jedoch fertil. Das ist vielleicht der erste Fall eines aus der Kreuzung zweier chasmogamer Spezies hervorgegangenen reinerbigen und voll fertilen kleistogamen Taxons. Es läßt sich auch der Umfang und die Art der durch Hybridisierung und durch Polyploidie verursachten Änderung des Zuchtsystems erkennen. Die Chromosomenzahl bei 6 von 16 obligaten kleistogamen Taxa (Tab. 4) zeigt, daß sie hochpolyploid sind. Vielleicht sind sie auf eine gleiche Weise wie im vorliegenden Falle entstanden.相似文献
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Dr AR Holmes RD Cannon HF Jenkinson 《Journal of industrial microbiology & biotechnology》1995,15(3):208-213
The yeastCandida albicans coaggregates with a variety of streptococcal species, an interaction that may promote oral colonization by yeast cells.C. albicans andCandida tropicalis are the yeasts most frequently isolated from the human oral cavity and our data demonstrate that both these species bind toStreptococcus gordonii NCTC 7869 while two otherCandida species (Candida krusei andCandida kefyr) do not. Adherence ofC. albicans was greatest when the yeast had been grown at 30° C to mid-exponential growth phase. For 21 strains ofC. albicans there was a positive correlation between the ability to adhere toS. gordonii and adherence to experimental salivary pellicle. Whole saliva either stimulated or slightly inhibited adherence ofC. albicans toS. gordonii depending on the streptococcal growth conditions. The results suggest that the major salivary adhesins and coaggregation adhesins ofC. albicans are co-expressed. 相似文献
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AbstractBacteria from two areas in Wales have been extracted and partially identified. The areas are a copper impregnated bog in the Coed-Y-Brenin Forest with low pH and high carbon and copper content, and the Morfa Harlech salt marshes which have neutral pH and lower copper and carbon. Bacillus spp. was the predominant bacterium in both soils, but there was increased diversity of bacteria in the salt marsh soils. Bacteria from the Cu-rich, Coed-Y-Brenin soils showed higher growth densities in nutrient agar plates containing 10, 30 and 100 μg cm?3 Cu than bacteria from the salt marsh soils, indicating that bacteria from the Coed-Y-Brenin soils could tolerate higher copper concentrations. Pseudomonas spp. from both study areas grew better in media with added Cu at low levels. The possibility is discussed that the bacteria play a part in the bioavailability of Cu particularly in the copper-rich Coed-Y-Brenin area. 相似文献