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1.
Mycobacterium avium subsp. paratuberculosis is an important pathogen that causes Johne's disease in animals and has been implicated in Crohn's disease in man yet few data exist on its physiological adaptation in either the host or the environment. In this study, the proteomic responses of the two distinct strains of M. a. paratuberculosis, cattle (C) and sheep (S), to hypoxia and starvation were studied in vitro. Nutrient starvation inhibited growth of both strains and was lethal for S strain after 12 weeks. Hypoxia induced a state of very low metabolic activity but rapid resuscitation occurred upon restoration of an aerobic atmosphere, consistent with the dormancy response of other mycobacteria. A total of 55 protein spots differentially expressed in response to starvation and/or hypoxic stress in one or both strains were identified from 2D gels and classified based on biological function. Antioxidant enzymes, oxidoreducatse enzymes and proteins involved in amino acid metabolism, fatty acid metabolism, ATP and purine biosynthesis, proteolysis, cell wall synthesis, protein synthesis, signal recognition and hypothetical proteins with putative functions including dormancy response regulators and universal stress proteins were identified. These proteins are potential screening targets for future diagnosis, prevention and control of M. a. paratuberculosis infection and their identification will assist understanding the pathogenesis of diseases caused by this organism.  相似文献   
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ABSTRACT

The study aimed to evaluate the effects of carrot concentrated protein (CCP) as additive on the functional and textural properties of surimi from striped catfish (Pangasianodon hypophthalmus) during six months of frozen storage (?20°C). The CCP (82.22% crude protein) was used as an additive either a lone or with a synthetic cryoprotectant (sucrose-sorbitol-sodium tri-polyphosphate). Control was made with synthetic cryoprotectant only. Molecular weight of CCP was found to be 36 kDa. After six months, the results revealed that up to 50% of synthetic cryoprotectants could be replaced by CCP during frozen storage of surimi. Biochemical parameters such as protein solubility, Ca2+ATPase activity, and gel strength decreased significantly (p < .05) during storage. Treatment T-3 (CCP 0.5% + 50% of synthetic cryoprotectant) maintained quality of protein significantly superior (p < .05) in respect to denaturation and other functional and sensory attributes compared to all the treatments. The microstructure images of surimi confirmed that addition of CCP modified the ice crystal growth during frozen storage. This study suggests that CCP can be a potential additive to protect protein from denaturation along with partial replacement of chemical cryoprotectants.  相似文献   
3.
Malignant catarrhal fever (MCF) is a fatal herpesvirus infection of domestic and wild ruminants, with a short and dramatic clinical course characterized primarily by high fever, severe depression, swollen lymph nodes, salivation, diarrhea, dermatitis, neurological disorders, and ocular lesions often leading to blindness. In the present study, fatal clinical cases of sheep associated malignant catarrhal fever (SA-MCF) were identified in cattle in the state of Karnataka. These cases were initially presented with symptoms of diarrhea, respiratory distress, conjunctivitis, and nasal discharges. Laboratory diagnosis confirmed the detection of ovine herpesvirus-2 (OvHV-2) genome in the peripheral blood samples of two ailing animals. The blood samples collected subsequently from sheep of the neighboring areas also showed presence of OvHV-2 genome indicating a nidus of infection in the region. The positive test results were further confirmed by nucleotide sequencing of the OIE approved portion of tegument gene as well as complete ORF8 region of the OvHV-2 genome. Phylogenetic analysis based on the sequence of the latter region indicated close genetic relationship with other OvHV-2 reported elsewhere in the world.  相似文献   
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The present study was undertaken with the objective of studying use and contribution of information sources in the purchase of agri-inputs by Indian farmers. The importance of an information source was measured in terms of its relevance as perceived by the farmers during the buying process. The study revealed that farmers preferred noncommercial, personal sources of information and the number of information sources used by them depended on the perceived importance of the product, the various options (brands) available to them, and credibility of the information sources. The personal characteristics of farmers did not have a significant influence on the number of information sources used by the farmers.  相似文献   
7.
The value of environmental regulation through command and control measures has been questioned because of inflexibility and high cost. Voluntary environmental initiatives have been proposed as an alternative approach to save costs, overcome problems of inadequate enforcement and monitoring and to take advantage of the environmental leadership of transnational corporations (TNCs). Amongst voluntary environmental initiatives certified environmental management system standards have so far had most impact in Singapore and the rest of Southeast Asia. This paper investigates the environmental policy statements of 52 ISO14001 certified organisations in Singapore and shows that the environmental commitments being made are no substitute for traditional environmental regulations.  相似文献   
8.
The Western Himalayan region of India possesses rich genetic diversity of rice (Oryza sativa L.). Rice landraces having withstood the rigors of biotic and abiotic stresses, suit to the local conditions of farms and reflect socio-cultural preferences can still be found in crop fields located distantly in rural and tribal areas. This region is known for growing World fame basmati in the foot hills and many varieties of red rices grown at higher elevations, known for cold tolerance and medicinal properties. Genetic resources of rice were collected for about 8 years (1999–2006) and 1069 germplasm accessions including 154 named landraces were collected. Prominent landraces such as Begumi, Ramjwain, Thapachini, Naurang, Hansraj, Tilakchandan, Lalsati, Jhini, Mushakbudji, Jattoo, Barpasso, Qadirbeigh, Safedbrez, Shahie known for their special quality attributes were collected. The change in land use, cropping patterns and aggressive introduction of modern varieties in the region has resulted in the loss of a large number of landraces especially from irrigated lands. The present paper looks at the status of rice genetic resources, genetic variability, genetic erosion and future strategies to conserve rice germplasm on farm and to maximize its use in rice breeding.  相似文献   
9.
Grain legumes, the important constituents of sustainability‐based cropping systems and energy‐limited vegetarian diets have long been the subject of scientific research. Tremendous technological strides were made in the so‐called orphan crops, in terms of both varietal improvement and generation of basic information. Despite recalcitrancy and high genotype dependency, in vitro culture techniques such as organogenesis, in vitro mutagenesis, embryo rescue and in vitro gene transfer have been deployed for improvement of several grain legumes and these played an important role in introgression of desirable genes from related and distant species and creation of additional genetic variability. Stable and reproducible regeneration protocols resulted in the development of genetically modified chickpea, pigeon pea, cowpea, mungbean, etc., while embryo rescue was deployed successfully for recovery of interspecific recombinants, a few of them exploited for the development of commercial cultivars. Nevertheless, doubled haploidy witnessed limited success and protoplast regeneration and in vitro mutagenesis remained of academic interest. The present review focuses on the progress, achievements, constraints and perspectives of using in vitro technology in grain legume improvement.  相似文献   
10.
NB7 silk fiber (Bombyx mori) was irradiated with the maximum dose range of 100 kGy using 8 MeV electron beam at room temperature. Irradiation effect in these fibers is quantified in terms of the changes in microstructural parameters employing X-ray diffraction line profile analysis technique. For this purpose we have used three asymmetric distribution functions for column lengths in a crystal. The decreasing trend of crystallite size values (〈N〉 as well as D s ) and crystallinity with increasing dosage of radiation clearly indicates the degradation of fiber. Of the several factors responsible for such a behavior, we presume that the chain scission of polymer network is a significant one over others and it is well pronounced here, leading to low molecular weight of the samples. This degradation is attributed to many changes in tensile properties of the polymer. Comparison of SEM photographs also confirms the X-ray results.  相似文献   
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