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81.
An organic solvent-tolerant bacterium designated as 146 capable of producing an organic solvent-stable alkaline protease was isolated from contaminated soil of a wood factory. The strain was a Gram-positive, spore-forming, nitrate-positive, rod-shaped organism capable of hydrolysing gelatine, starch, skim milk and identified asBacillus cereus. Activity of the protease was drastically increased in the presence of 1–decanol, isooctane, n-dodecane and n-tetradecane, but reduced in the presence of ethyl acetate, benzene, toluene, 1-heptanol, ethylbenzene and hexane. The bacterium was shown to require lactose as a carbon source and peptone as a nitrogen source. The optimum fermentation condition for the production of alkaline protease was in the presence of beef and yeast extract. Optimum pH was determined to be at 10.0 at incubation temperature of 37 °C for 48 h. Results from the studies suggest that 146 is a new strain of Bacillus cereus capable of producing organic solvent-tolerant alkaline protease with potential use in industries.  相似文献   
82.
83.
This article asserts that the most important physical feature distinguishing man from all other creatures, one which allowed for and contributed to the development of the thumb and the brain, which facilitated and encouraged the development of his imagination, his ability to think abstractly and even to doubt, and made it possible for him to master all other life forms and advance so far in containing and even conquering some forces of nature is his well-developed posterior; superior to that of all other living creatures: while sitting comfortably for long periods freed his hands and vision, it also allowed him to imagine and ponder what was over the horizon.  相似文献   
84.
The distribution of microorganisms in 10 samples of salted dried fish and the effects of irradiation of them were studied. The total aerobic bacteria in commercial dried fish were determined to be from 2 × 104 to 3 × 106 per gram. Mold counts were 1 × 102 to 7 × 103 per gram with a lower amount of yeasts. In spoiled dried fish, total aerobic bacteria were determined to be 4× 106 or 1 × 107 per gram with a few yeasts. Coliforms were not isolated on MacConkey agar plates from any of the samples. The predominant bacteria occurring in spoiled dried fish were Pediococcus halophilus, Vibrio costicola and Planococcus sp. More than 50% of the molds consisted of the Aspergillus niger group, whereas lower amounts of the A. flavus, A. fumigatus and A. ochraceus groups, Penicillium chrysogenum series, etc. were also isolated from many samples of dried fish. All kinds of putrefactive microorganisms were radiation sensitive, and a dose of ca. 500 krad appears to be sufficient for extension of the shelf-life of dried fish from 2 to 4 times.  相似文献   
85.
Tarap Hill Reserve, the largest upland reserve of Bangladesh, is situated along the Indo-Burma Biodiversity Hotspot. It encompasses the last remaining patches of natural vegetation in the Northeastern Tarap Mountain System and harbors 87 % of the nationally declared red-listed vascular plant species. Despite requiring high conservation priority, this is one of the least studied reserves in the tropics. In this study, we collected vegetation and soil (eight variables) data from 68 sample plots. We identified the tree communities by cluster analysis and verified them using the multi-response permutation procedure and detrended correspondence analysis. Species richness, diversity, and compositional similarity between the communities were also estimated. In total, 116 tree species representing 69 genera were recorded within the four identified tree community types. Finally, canonical correspondence analysis with associated Monte Carlo permutation tests (499 permutations) was performed to explore the patterns of variation in tree species distribution explained by the soil variables. Soil phosphorus, organic matter content, and pH were most closely correlated with tree compositional variation. Thus, conservation strategies that take into account variations in these influential soil factors may aid in the conservation of trees in the reserve.  相似文献   
86.
Coral sands off Réunion Island and Rodrigues (Mascarene archipelago, Western Indian Ocean) support diverse diatom communities, particularly rich in Monoraphidineae. Recent surveys of reef environments (June 2005 and June 2007) permitted the recognition of several taxa belonging to the diatom genus Cocconeis, among which are two new, relatively small taxa, epipsammic on coral sand. Cocconeis coronata Riaux-Gobin et Romero sp. nov. is similar to C. scutellum but has its own distinctive features. In external view, the concave raphe valve possesses uniseriate striae and a subsident hyaline marginal rim, while the strongly convex sternum valve has a submarginal, generally continuous crest, a hexagonal pattern of areolation, short, rounded spines that are often regularly arranged around valve face areolae, a complex areola hymen and small marginal chambers. Some morphometric differences were noted between the populations of C. coronata at Réunion and Rodrigues. Cocconeis margaritata Riaux-Gobin et Al-Handal, sp. nov. is smaller, possesses a sternum valve like that of C. placentula and C. neothumensis, but has denser striation and small pearl-like concretions around the areola aperture on the sternum valve. Several other taxa that resemble, or may be varieties of, C. margaritata require further study before being formally described. Cocconeis margaritata and C. coronata are small and relatively rare, so their study requires scanning electron microscopy.  相似文献   
87.
Interferons are important proteins for the immune system because of their antiviral, anti‐proliferating and immunomodulatory activities. Therapeutic value of these proteins against certain types of tumors caused interest and investigations aimed to obtain highly purified interferons. Molecular imprinting is an efficient method for purification with high selectivity, specificity and good reproducibility. In this study, we utilized advantages of molecular imprinting technique for the purification of interferon from human gingival fibroblast culture. For this purpose, interferon α‐2b imprinted poly(hydroxyethyl methacrylate) cryogel (hIFN‐α‐MIP) was prepared. Optimum adsorption conditions were determined, and maximum adsorption capacity of hIFN‐α‐MIP cryogel was found as 254.8 × 104 IU/g from aqueous solution. All interferon measurements are expressed as International Unit (IU), which is a unit measurement used to quantify biologically active substances like interferon based on their biological activity or effect. Selectivity experiments were performed using competitive proteins and repeated adsorption–desorption studies showed that the adsorption capacity maintained almost at a constant value after ten cycles. For the purification of interferon from human gingival fibroblast culture, fast protein liquid chromatography was used and the specific activity of the purified interferon α‐2b on HeLa cell line was found between the values 3.45 × 108 IU/mg and 3.75 × 108 IU/mg. The results are promising, and the molecular imprinting technique is effective for the purification of interferon α‐2b. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
88.
Maize dwarf mosaic disease is one of the most important viral diseases of maize (Zea mays L.) throughout the world. It is caused by several virus species in the family Potyviridae, genus Potyvirus, including Maize dwarf mosaic virus (MDMV), Sugarcane mosaic virus (SCMV), Johnsongrass mosaic virus (JGMV) and Sorghum mosaic virus (SrMV). Resistance to another member of the family Potyviridae, Wheat streak mosaic virus (WSMV), is conferred by three alleles (Wsm1, Wsm2, Wsm3) in the maize inbred line Pa405, and these or closely linked genes were previously shown to confer resistance to the potyviruses MDMV and SCMV. In this study, we assessed whether Wsm alleles are linked to resistance to JGMV and SrMV. Near isogenic lines (NILs) carrying one or two of the Wsm alleles introgressed into the susceptible line Oh28 and F1 progeny from NIL × Oh28 were tested for their response to JGMV and SrMV. Our results indicate that Wsm1 provides resistance to both JGMV and SrMV in a dose-dependent manner. Wsm2 and Wsm3 each provide limited resistance, and combining Wsm alleles enhances that resistance.  相似文献   
89.
Sets of tetrasubstituted thiophene esters 4a-4g, 5a-5f and 6a-6e were synthesized by reaction of 1-(α-Carbomethoxy-β-aminothiocrotonoyl)-aryl/aroyl amines (3) with 3-(bromoacetyl)coumarin, 1,4-dibromodiacetyl and chloroacetone respectively. The compound 3 were synthesized by nucleophilic addition of aryl/aroylisothiocyanate and enamine (2). The synthesized targeted compounds (4a-4g, 5a-5f and 6a-6e) were evaluated for their in vivo anti-inflammatory activity in carrageenin-induced rat hind paw oedema model at three graded doses employed at 10, 20 and 40 mg/kg body weight using mefanamic acid, ibuprofen and in vivo analgesic activity in acetic acid induced writhing response model at 10 mg/kg dose using ibuprofen as standard drug. The compounds 4a-4f, 5c, 5f, 6c and 6e were evaluated for their in vitro antioxidant nitric oxide radical scavenging assay at the concentrations of 5, 10, 15, 20, 25, 30 and 35 μg/mL using ascorbic acid as standard drug. Among all the targeted compounds 4c showed maximum anti-inflammatory activity of 71% protection at 10 mg/kg and 77% protection at 20 mg/kg to inflamed paw and analgesic activity of 56% inhibition and also maximum in vitro nitric oxide radical scavenging activity having IC50 value 31.59 μg/mL.  相似文献   
90.

Background

Shigellosis continues to be a public health challenge for developing countries, including Bangladesh. The aim of the study is to demonstrate recent changes in Shigella sero-groups and their geographical diversity.

Methods

Data were extracted from data archive of four diarrheal disease surveillance systems. A 2% sub sample from urban Dhaka Hospital (2008–2011; n = 10,650), and 10% from urban Mirpur Treatment Centre (2009–2011; n = 3,585), were enrolled systematically; whereas, all patients coming from the Health and Demographic Surveillance System area in rural Matlab (2008–2011; n = 6,399) and rural Mirzapur (2010–2011; n = 2,812) were included irrespective of age, sex, and disease severity. A fresh stool specimen was collected for identification of Shigella spp. Of them, 315 (3%) were positive for Shigella in Dhaka, 490 (8%) from Matlab, 109 (3%) from Mirpur and 369 (13%) from Mirzapur and considered as analyzable sample size.

Results

Among all Shigella isolates regardless of age, significant decreases in percentage of S. flexneri over time was observed in Mirpur (55→29%; p value of χ2-for trend = 0.019) and Mirzapur (59→47%; p = 0.025). A non-significant decrease was also seen in Dhaka (58→48%), while in Matlab there was a non-significant increase (73→81%). Similar patterns were observed among under-5 children at all sites. Emergence of S. sonnei was found in Dhaka (8→25%; p<0.001) and Mirpur (10→33%; p = 0.015), whereas it decreased in Mirzapur (32→23%; p = 0.056). The emergence of S. boydii was seen in all ages in Mirzapur [(3→28%; p<0.001); (3→27%; p<0.001)]. On the other hand, we saw non-significant percent reductions in S. boydii in Dhaka [overall (25→16%); under-5 (16→9%)]. Decreasing rates of Shigella dysenteriae were observed in Matlab, Mirpur and Mirzapur; whereas, in Dhaka it remained unchanged.

Conclusion and Significance

Emergence of S. sonnei and S. boydii as important infectious diarrhea etiologies and variations in geographical diversity underscore the need for monitoring, with possible implications for vaccine development.  相似文献   
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