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11.
Early detection of bladder cancer is particularly important since it dramatically affects the survival rates. However, neither urinary cytology nor tumor markers that are currently used are sensitive enough for the early detection of bladder cancer or recurrent disease. The ras genes are frequently mutated in cancer. In this study, we investigated the diagnostic potential of ras mutation analysis in urinary sediments of patients with bladder cancer using a single-strand conformation polymorphism analysis and polymerase chain reaction. Mutation in codon 12 of the H-ras gene was observed in 39% of the patients. Our results indicate that this approach may significantly improve diagnostic sensitivity in detecting bladder tumors.  相似文献   
12.
We earlier reported that overexpression of glia maturation factor (GMF) in cultured astrocytes enhances the production of brain-derived neurotrophic factor (BDNF). The current study was conducted to find out whether BDNF production is impaired in animals devoid of GMF. To this end GMF-knockout (KO) mice were subjected to exercise and the neurotrophin mRNAs were determined by real-time RT-PCR. Compared to wild-type (WT) mice, there is a decrease in exercise-induced BDNF in the KO mice. The observation was correlated with the finding that, in WT mice, exercise increases GMF expression. The results are consistent with the hypothesis that GMF is necessary for exercise-induction of BDNF, and that GMF may promote neuroprotection through BDNF production.  相似文献   
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Petroleum pollution is a major concern in Antarctica due to the persistent nature of its hydrocarbon components coupled with the region’s extreme environmental conditions, which means that bioremediation approaches are largely inapplicable at present. The current study assessed the ability of the psychrotolerant phenol-degrader, Rhodococcus sp. strain AQ5-07, to assimilate diesel fuel as the sole carbon source. Factors expected to influence the efficiency of diesel degradation, including the initial hydrocarbon concentration, nitrogen source concentration and type, temperature, pH and salinity were studied. Strain AQ5-07 displayed optimal cell growth and biodegradation activity at 1% v/v initial diesel concentration, 1 g/L NH4Cl concentration, pH 7 and 1% NaCl during one-factor-at-a-time (OFAT) analyses. Strain AQ5-07 was psychrotolerant based on its optimum growth temperature being near 20 °C. In conventionally optimised media, strain AQ5-07 showed total petroleum hydrocarbons (TPH) mineralisation of 75.83%. However, the optimised condition for TPH mineralisation predicted through statistical response surface methodology (RSM) enhanced the reduction to 90.39% within a 2 days incubation. Our preliminary data support strain AQ5-07 being a potential candidate for real-field soil bioremediation by specifically adopting sludge-phase bioreactor system in chronically cold environments such as Antarctica. The study also confirmed the utility of RSM in medium optimisation.

  相似文献   
15.
Genus Rusa, belonging to the deer family Cervidae is native to the Indo-Malaya Archipelago (IMA). However, detailed information on the Rusa genus in the IMA is limited. This review provides comprehensive information on the Rusa genus in the IMA including, threats and conservation efforts. There are four species of deer in Rusa genus, which is Sambar deer (Rusa unicolor), Javan deer (Rusa timorensis), Visayan spotted deer (Rusa alfredi) and Philippine deer (Rusa marianna). Despite their wide distribution in the South Asian and Southeast Asian regions, they are under serious threats. Some conservation efforts that are being done to protect and conserve them among others are; (1) facilities protection, (2) habitat enrichment programme, (3) Ex-situ conservation, (4) legislations, and (5) captive breeding. Conservation through genetics is also an important step in conserving these species. Recommendations for conservation of the genus are also discussed; 1. maintenance of ecosystem. 2. more effective monitoring system on the existing protected area. 3. ex-situ conservation, and 4. habitat monitoring.  相似文献   
16.

Aims

The aim of this study was to characterize Streptococcus agalactiae strains that were isolated from fishes in Malaysia using random amplified polymorphic DNA (RAPD) and repetitive extragenic palindromic PCR (REP‐PCR) techniques.

Methods and Results

A total of 181 strains of Strep. agalactiae isolated from red hybrid tilapia (Oreochromis sp.) and golden pompano (Trachinotus blochii) were characterized using RAPD and REP‐PCR techniques. Both the fingerprinting techniques generated reproducible band patterns, differing in the number and molecular mass amplicons. The RAPD technique displayed greater discriminatory power by its production of more complex binding pattern and divided all the strains into 13 groups, compared to 9 by REP‐PCR technique. Both techniques showed the availability to differentiate the genetic profiles of the strains according to their geographical location of origin. Three strains of Strep. agalactiae that were recovered from golden pompano showed a genetic dissimilarity from the strains isolated from red hybrid tilapia, while the strain of ATCC 27956 that recovered from bovine displayed a unique profile for both methods.

Conclusions

Both techniques possess excellent discriminative capabilities and can be used as a rapid means of comparing Strep. agalactiae strains for future epidemiological investigation.

Significance and Impact of the Study

Framework as the guideline in traceability of this disease and in the search for potential local vaccine candidates for streptococcosis in this country.  相似文献   
17.
After determination of sorption isotherms of grape seeds using gravimetric method, five models with temperature effect were used to fit water sorption isotherms of grape seeds to investigate temperature effect on sorption isotherms and its thermodynamic characteristics. Halsey model had minimum mean relative percentage error (M e ) and all other models used were good in fitting experimental data (with M e of less than 10 %). Differential parameters such as net isosteric heat, isosteric heat, differential entropy and integral function such as equilibrium heat, net equilibrium heat, integral entropy and surface potential have been calculated. The net isosteric heat, isosteric heat and differential entropy decreased with moisture content. The net equilibrium enthalpy, equilibrium enthalpy and integral entropy decreased with moisture content. The surface potential at four temperatures (35, 45, 55 and 65 °C) was estimated, and low temperature effect was reported.  相似文献   
18.
Intranasally administered influenza vaccines could be more effective than injected vaccines, because intranasal vaccination can induce virus-specific immunoglobulin A (IgA) antibodies in the upper respiratory tract, which is the initial site of infection. In this study, immune responses elicited by an intranasal inactivated vaccine of influenza A(H5N1) virus were evaluated in healthy individuals naive for influenza A(H5N1) virus. Three doses of intranasal inactivated whole-virion H5 influenza vaccine induced strong neutralizing nasal IgA and serum IgG antibodies. In addition, a mucoadhesive excipient, carboxy vinyl polymer, had a notable impact on the induction of nasal IgA antibody responses but not on serum IgG antibody responses. The nasal hemagglutinin (HA)-specific IgA antibody responses clearly correlated with mucosal neutralizing antibody responses, indicating that measurement of nasal HA-specific IgA titers could be used as a surrogate for the mucosal antibody response. Furthermore, increased numbers of plasma cells and vaccine antigen-specific Th cells in the peripheral blood were observed after vaccination, suggesting that peripheral blood biomarkers may also be used to evaluate the intranasal vaccine-induced immune response. However, peripheral blood immune cell responses correlated with neutralizing antibody titers in serum samples but not in nasal wash samples. Thus, analysis of the peripheral blood immune response could be a surrogate for the systemic immune response to intranasal vaccination but not for the mucosal immune response. The current study suggests the clinical potential of intranasal inactivated vaccines against influenza A(H5N1) viruses and highlights the need to develop novel means to evaluate intranasal vaccine-induced mucosal immune responses.  相似文献   
19.
We previously demonstrated that glia maturation factor (GMF), a brain specific protein, isolated, sequenced and cloned in our laboratory, induce expression of proinflammatory cytokines and chemokines in the central nervous system. We also reported that the up-regulation of GMF in astrocytes leads to the destruction of neurons suggesting a novel pathway of GMF-mediated cytotoxicity of brain cells, and implicated its involvement in the pathogenesis of inflammatory neurodegenerative diseases. In the present study, we examined the expressions of GMF in triple-transgenic Alzheimer’s disease (3xTg-AD) mice. Our results show a 13-fold up-regulation of GMF and 8–12-fold up-regulation of proinflammatory cytokines tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), IL-1β, interferon gamma (IFN-γ), and chemokine (C–C motif) ligand 2 (CCL2) and C–X–C motif chemokine 10 (CXCL10/IP-10) mRNA as determined by quantitative real-time RT-PCR in the brain of 3xTg-AD mice as compared to non-transgenic (Non-Tg) mice. In conclusion, the increase in GMF and cytokine/chemokine expression was correlated with reactive glial fibrillary acidic protein positive astrocytes and ionized calcium binding adaptor molecule 1 (Iba-1)-positive microglia in 3xTg-AD mice.  相似文献   
20.
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