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61.
AIM: Formulation of an inexpensive cane molasses medium for improved cell-bound phytase production by Pichia anomala. METHODS AND RESULTS: Cell-bound phytase production by Pichia anomala was compared in synthetic glucose-beef extract and cane molasses media. The yeast was cultivated in 250 ml flasks containing 50 ml of the medium, inoculated with a 12 h-old inoculum (3 x 10(6) CFU ml(-1)) and incubated at 25 degrees C for 24 h at 250 rev min(-1). Different cultural parameters were optimized in cane molasses medium in batch fermentation. The cell-bound phytase content increased significantly in cane molasses medium (176 U g(-1) dry biomass) when compared with the synthetic medium (100 U g(-1) dry biomass). In fed-batch fermentation, a marked increase in biomass (20 g l(-1)) and the phytase yield (3000 U l(-1)) were recorded in cane molasses medium. The cost of production in cane molasses medium was pound 0.006 per 1000 U, which is much lower when compared with that in synthetic medium (pound 0.25 per 1000 U). CONCLUSIONS: An overall 86.6% enhancement in phytase yield was attained in optimized cane molasses medium using fed-batch fermentation when compared with that in synthetic medium. Furthermore, the production in cane molasses medium is cost-effective. SIGNIFICANCE AND IMPACT OF THE STUDY: Phytase yield was improved in cane molasses when compared with the synthetic medium, and the cost of production was also significantly reduced. This enzyme can find application in the animal feed industry for improving the nutritional status of feed and combating environmental pollution.  相似文献   
62.
Summary An alkalophilicBacillus sp. NG-27, which produced a thermostable xylanase was isolated from soil. The xylanase was active in the temperature range of 40–90°C with a temperature optimum at 70°C. It had a half life of 75 min at 70°C.  相似文献   
63.
Histamine and relatively selective H1- and H2-receptor agonists caused a concentration-dependent increase in the fractional outflow of radioactivity from the rat isolated vas deferens preloaded with labelled noradrenaline. The evoked fractional outflow of radioactivity was not preferentially associated with either H1- or H2-selective agonists, nor was it related to the known potencies of the agonists within each group. The evoked fractional outflow caused by all compounds studied was independent of the extracellular Ca2+ concentration. The study cautions against ascribing all the effects of histamine analogs to their respective histamine receptor stimulation.  相似文献   
64.
The performance of biomaterials designed for bone repair depends, in part, on the ability of the material to support the adhesion and survival of mesenchymal stem cells (MSCs). In this study, a nanofibrous bone-mimicking scaffold was electrospun from a mixture of polycaprolactone (PCL), collagen I, and hydroxyapatite (HA) nanoparticles with a dry weight ratio of 50/30/20 respectively (PCL/col/HA). The cytocompatibility of this tri-component scaffold was compared with three other scaffold formulations: 100% PCL (PCL), 100% collagen I (col), and a bi-component scaffold containing 80% PCL/20% HA (PCL/HA). Scanning electron microscopy, fluorescent live cell imaging, and MTS assays showed that MSCs adhered to the PCL, PCL/HA and PCL/col/HA scaffolds, however more rapid cell spreading and significantly greater cell proliferation was observed for MSCs on the tri-component bone-mimetic scaffolds. In contrast, the col scaffolds did not support cell spreading or survival, possibly due to the low tensile modulus of this material. PCL/col/HA scaffolds adsorbed a substantially greater quantity of the adhesive proteins, fibronectin and vitronectin, than PCL or PCL/HA following in vitro exposure to serum, or placement into rat tibiae, which may have contributed to the favorable cell responses to the tri-component substrates. In addition, cells seeded onto PCL/col/HA scaffolds showed markedly increased levels of phosphorylated FAK, a marker of integrin activation and a signaling molecule known to be important for directing cell survival and osteoblastic differentiation. Collectively these results suggest that electrospun bone-mimetic matrices serve as promising degradable substrates for bone regenerative applications.  相似文献   
65.
There has been a rapid increase in the amount of mutational data due to, amongst other things, an increase in single nucleotide polymorphism (SNP) data and the use of site-directed mutagenesis as a tool to help dissect out functional properties of proteins. Many manually curated databases have been developed to index point mutations but they are not sustainable with the ever-increasing volume of scientific literature. There have been considerable efforts in the automatic extraction of mutation specific information from raw text involving use of various text-mining approaches. However, one of the key problems is to link these mutations with its associated protein and to present this data in such a way that researchers can immediately contextualize it within a structurally related family of proteins. To aid this process, we have developed an application called MutationMapper. Point mutations are extracted from abstracts and are validated against protein sequences in Uniprot as far as possible. Our methodology differs in a fundamental way from the usual text-mining approach. Rather than start with abstracts, we start with protein sequences, which facilitates greatly the process of validating a potential point mutation identified in an abstract. The results are displayed as mutations mapped on to the protein sequence or a multiple sequence alignment. The latter enables one to readily pick up mutations performed at equivalent positions in related proteins. We demonstrate the use of MutationMapper against several examples including a single sequence and multiple sequence alignments. The application is available as a web-service at http://mutationmapper.bioch.ox.ac.uk.  相似文献   
66.
Two Mycobacterium avium subsp. paratuberculosis (MAP) antigens (native—S 5, ‘Bison type’ and commercial antigens ‘Bovine’), were compared for screening of kids against paratuberculosis infection. Using MAP (S 5) antigen (‘Bison type’) in plate ELISA, 47 serum samples driven from farmer's herds of Jakhrana, Sirohi, and Marwari breeds in their home tract in Rajasthan state were screened. Of the 47 kids randomly sampled, 8.5% were found sero-positive by plate ELISA test. Breed-wise sero-prevalence was 10.5%, 7.6%, and nil in the Jakhrana, Sirohi, and Marwari male kids, respectively. Whereas, none of the serum sample was found positive using commercial MAP ‘Bovine’ antigen. Sero-prevalence of paratuberculosis has been found to be low in young kids (2 months old) belonging to the farmer's herds of Jakhrana and Marwari in their home tracts.  相似文献   
67.

Background

Previous studies have found that up to 60% of children with neurologic conditions have tried complementary and alternative medicine (CAM).

Objective

To assess the use of CAM among patients presenting to neurology clinics at two academic centers in Canada.

Methods

A survey instrument was developed to inquire about use of CAM products and therapies, including reasons for use, perceived helpfulness, and concurrent use with conventional medicine, and administered to patients or their parents/guardians at the Stollery Children''s Hospital in Edmonton and the Children''s Hospital of Eastern Ontario (CHEO) in Ottawa.

Results

Overall CAM use at the Stollery was 78%, compared to 48% at CHEO. The most common CAM products used were multi-vitamins (84%), vitamin C (37%), homeopathic remedies (24%), and fish oil/omega 3 s (22%). The most common CAM practices used were massage (47%), chiropractic (37%), faith healing (18%), aromatherapy (16%), homeopathy (16%), and relaxation (16%). Many patients used CAM products at the same time as conventional medicine but just over half (57%) discussed this concurrent use with their physician.

Conclusion

CAM use is common in pediatric neurology patients and most respondents felt that it was helpful, with few or no harms associated. However, this use is often undisclosed, increasing possibility of interactions with conventional drugs. We urge clinicians to inquire about CAM use during routine history taking at every patient visit. Parents would clearly like more information about CAM from their specialty clinics; such information would be easier to share if more primary data were available about the safety and effectiveness of commonly used therapies.  相似文献   
68.
The three currently recognised Photorhabdus species are bioluminescent bacteria that are pathogenic to insects. P. luminescens and P. temperata form a symbiotic relationship with nematodes that infect insects. P. asymbiotica, on the other hand, has only been isolated from human clinical specimens from the USA and Australia. The bacterium has been associated with locally invasive soft tissue and disseminated bacteraemic infections. An invertebrate vector for P. asymbiotica has not yet been identified.  相似文献   
69.
Streptococcus pyogenes causes pharyngitis in school age children, which if left untreated causes acute rheumatic fever (ARF) that later progress toward rheumatic heart disease (RHD). The pathogenesis of this disease and its progression as post infectious squeal is not well understood. In this study, percentages of CD4(+) and CD8(+) T-cells were compared among patients of ARF, RHD and Chronic RHD using flow cytometer. The production of Th1/Th2 cytokines from serum and endothelial cells of damaged and normal heart valves was also analyzed using flow cytometer. Results showed an inverse proportion of CD4(+) and CD8(+) T-cell numbers in ARF and RHD patients. Cytokine assay demonstrated a switch-over from Th1 to Th2 type, as the disease progressed. We observed significantly high IL-6 in ARF patients and high TNF-α in early RHD patients which allowed us to construct a hypothesis, that, during initial infection phase, lot of antibodies are produced (via IL-6) and TNF-α has a role in disease progression and tissue damage during RHD phase.  相似文献   
70.
A 36-kDa antigen of axenically grown pathogenic Entamoeba histolytica (HM1-IMSS) was eluted from the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)-resolved crude amoebic extract antigens. The immunoreactivity of this partially purified 36-kDa antigen with monoclonal antibody (MoAb) 3D(10) altered significantly (P<0.01) after heat and trypsin treatment but remained unaltered after treatment with sodium metaperiodate (P0.5), thereby indicating the protein nature of the epitope recognized by MoAb 3D(10). The epitope was found to be localized on the surface as well as in the cytoplasm of the E. histolytica trophozoites with the majority of it in the cytoplasm. In addition, this epitope was also found to be present on the cyst form of the parasite. The 36-kDa molecule was recognized by the sera from 29 (85%) of the 34 patients with amoebic liver abscess and five (83%) of the six patients with amoebic colitis. No serum samples from asymptomatic cyst passers, from patients with non-amoebic hepatic or intestinal disorders and apparently healthy subjects had antibodies that reacted with this 36-kDa molecule. The immune responses in man to this 36-kDa amoebic molecule indicate a potential specific role for this molecule in invasive amoebiasis.  相似文献   
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