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91.
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Prostate cancer is a major cause of cancer-related death in males. Wnt/β-catenin signaling plays a critical role in the pathogenesis of this disease by regulating angiogenesis, drug resistance, cell proliferation, and apoptosis. Suppression of Wnt canonical or noncanonical signaling pathways via Wnt biological or pharmacological antagonists is a potentially novel therapeutic approach for patients with prostate cancer. This review summarizes the role of Wnt signaling inhibitors in the pathogenesis of prostate cancer for a better understanding and hence a better management of this disease.  相似文献   
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Much research has been conducted about different types of fermentation at high temperature, but only a few of them have studied cell viability changes during high-temperature fermentation. In this study, Acetobacter senegalensis, a thermo-tolerant strain, was used for gluconic acid production at 38 °C. The influences of different carbon sources and physicochemical conditions on cell viability and the resuscitation of viable but nonculturable (VBNC) cells formed during fermentation were studied. Based on the obtained results, A. senegalensis could oxidize 95 g l− 1 glucose to gluconate at 38 °C (pH 5.5, yield 83%). However, despite the availability of carbon and nitrogen sources, the specific rates of glucose consumption (qs) and gluconate production (qp) reduced progressively. Interestingly, gradual qs and qp reduction coincided with gradual decrease in cellular dehydrogenase activity, cell envelope integrity, and cell culturability as well as with the formation of VBNC cells. Entry of cells into VBNC state during stationary phase partly stemmed from high fermentation temperature and long-term oxidation of glucose, because just about 48% of VBNC cells formed during stationary phase were resuscitated by supplementing the culture medium with an alternative favorite carbon source (low concentration of ethanol) and/or reducing incubation temperature to 30 °C. This indicates that ethanol, as a favorable carbon source, supports the repair of stressed cells. Since formation of VBNC cells is often inevitable during high-temperature fermentation, using an alternative carbon source together with changing physicochemical conditions may enable the resuscitation of VBNC cells and their use for several production cycles.

  相似文献   
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Abstract

In thyroid cells, a PI-agonist, via G1 like protein, enhanced a TSH-induced I?-efflux by intensifying a TSH-dependent inositol polyphosphate production followed by a Ca2+ mobilization, but diminished a TSH-dependent DNA synthesis by attenuating a TSH-dependent cAMP accumulation.  相似文献   
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Tumor necrosis factor a (TNFa) is an inflammatory cytokine that plays a crucial role in the immune response and the progression of cervical lesions. There is a growing body of data evaluating the value of a genetic variant in the TNFa gene with the risk of developing cervical cancer. The aim of this study was to explore the association of a variant, TNF-308 G>A, residing in the TNFa gene with cervical cancer. A total of 91 women with cervical cancer and 161 women as the control group were recruited. DNA was extracted, and Taqman®-probes-based assay was used for genotyping. Our results showed that the minor allele frequency was 0.3 in total population, and the frequency of minor allele A was more in the case group compared with the control. The regression models in different genetic models also revealed that the allele A is a potential risk factor for the development of cervical cancer. In particular, in the dominant model, patients with AG and AA genotypes had a higher risk of developing cervical cancer with odds ratio (OR) of 2.75 (95% confidence interval [CI]: 1.57-4.83, <0.001) and OR of 7.27 (95%CI: 2.5-20.8, <0.001), compared with the GG genotype. Moreover, a similar outcome was obtained for smear test results. Our study demonstrated that TNF-308 G>A located on TNF-a was associated with the risk of cervical cancer, supporting further studies in a larger population and multicenter setting to show the value of emerging markers as risk stratification biomarkers in cervical cancer.  相似文献   
98.
Despite great advances in the field of vaccination, there are still needs for novel and effective vaccines because still no effective vaccines have been produced for some diseases such as malaria, acquired immune deficiency syndrome (AIDS), and tuberculosis. Furthermore, many of the existing vaccines have disadvantages such as failure to stimulate completely the immune system, in vivo instability, high toxicity, the need for cold chain, and multiple administrations. Nanotechnology has been raised as a powerful tool for solving these problems in this regard. Generally, nanovaccines are a new generation of vaccines using nanoparticles (NPs) as carriers and/or adjuvants. Due to the similar scale (size) between the NPs and pathogens, the immune system can be stimulated well, resulting in triggered cellular and humoral immunity responses. Other benefits of the nanovaccines include their better stability in blood flow to increase the shelf life in blood, enhanced immune system stimulation, no need for booster doses, no need to maintain the cold chain, and ability to create active targeting. In addition, nanovaccines have raised the hope to treat diseases such as rheumatoid arthritis, AIDS, malaria, and chronic autoimmune, and so forth.  相似文献   
99.
Electromagnetic fields (EMFs) are reported to interfere with chemical reactions involving free radical production. Coenzyme Q10 (CoQ10) is a strong antioxidant with some neuroprotective activities. The purpose of this study was to examine and compare the neuroprotective effects of EMF and CoQ10 in a mouse model of hippocampal injury. Hippocampal injury was induced in mature female mice (25–30 g), using an intraperitoneal injection of trimethyltin hydroxide (TMT; 2.5 mg/kg). The experimental groups were exposed to EMF at a frequency of 50 Hz and intensity of 5.9 mT for 7 hr daily over 1 week or treated with CoQ10 (10 mg/kg) for 2 weeks following TMT injection. A Morris water maze apparatus was used to assess learning and spatial memory. Nissl staining and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) tests were also performed for the histopathological analysis of the hippocampus. Antiapoptotic genes were studied, using the Western blot technique. The water maze test showed memory improvement following treatment with CoQ10 and coadministration of CoQ10 + EMF. The Nissl staining and TUNEL tests indicated a decline in necrotic and apoptotic cell count following treatment with CoQ10 and coadministration of CoQ10 + EMF. The Western blot study indicated the upregulation of antiapoptotic genes in treatment with CoQ10, as well as coadministration. Also, treatment with EMF had no significant effects on reducing damage induced by TMT in the hippocampus. According to the results, EMF had no significant neuroprotective effects in comparison with CoQ10 on hippocampal injury in mice. Nevertheless, coadministration of EMF and CoQ10 could improve the neuroprotective effects of CoQ10.  相似文献   
100.
The effect of Neotyphodium endophytes on growth parameters and zinc (Zn) tolerance and uptake was studied in two grass species of Festuca arundinacea and Lolium perenne. Plants were grown under different Zn concentrations (control, 200, 400, 800, and 1800 mg kg?1) in potted soil for 5 months. The results showed that the number of plant tillers was 85 and 51% greater in endophyte infected Festuca (FaEI) and Lolium (LpEI), respectively, compared to their endophyte free (EF) plants. Roots and shoots dry weights in infected Festuca were 87 and 9% greater than non-infected counterparts but in opposite, EF Lolium had 47 and 8% greater root and shoot dry weights than LpEI. Endophyte infected Festuca and Lolium improved chlorophyll fluorescence as Fv/Fm at high concentrations of Zn, showing their better chlorophyll functions and significant reduction of Zn stress in endophyte infected plants. Shoots of endophyte infectedFestuca had 82% greater concentration of Zn than EF Festuca when grown in soil containing 1800 mg kg?1 Zn. Festuca and Lolium may tolerate high Zn concentration in soil without reduction in shoot and root growth. Endophyte infection in Festuca may help the grass accumulate and transport more Zn in aboveground parts under Zn-stress, thereby aiding phytoremediation of contaminated soils.  相似文献   
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