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Probiotics and Antimicrobial Proteins - Nowadays, cancer remains a major cause of death affecting millions of people. Currently, the antimicrobial peptides (AMPs) as potent anticancer therapeutic...  相似文献   
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In present study, the capabilities of multiple linear regression (MLR) and adaptive neuro-fuzzy inference system (ANFIS) in developing pedotransfer functions (PTFs) for estimating geometric mean diameter (GMD) and mean weight diameter (MWD), from routine soil properties and combination of routine soil properties and fractal dimension of aggregates were evaluated. For this reason 101 samples were collected form the Northwest of Iran and some their properties such as soil texture, pH, cation exchange capacity (CEC), and organic matter (OM), fractal dimension of aggregates between number-diameter (Dn), mass-diameter (Dmt), and bulk density-diameter (Dmy) were determined and used as an input variables for determining of mean weight diameter (MWD) and geometric mean diameter (GMD) by MLR and ANFIS PTFs. Results showed that the application of fractal dimension of aggregates as a predictor in two methods improved the accuracy of PTFs. As well as, results showed that ANFIS have greater potential for determination of the relationships between soil aggregate stability indices and other soil properties in compared with MLR. Therefore using of adaptive neuro-fuzzy inference system (ANFIS) in developing pedotransfer functions is recommended.  相似文献   
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Background

Recent attention has focused on understanding the role of the brain-renin-angiotensin-system (RAS) in stroke and neurodegenerative diseases. Direct evidence of a role for the brain-RAS in Parkinson's disease (PD) comes from studies demonstrating the neuroprotective effect of RAS inhibitors in several neurotoxin based PD models. In this study, we show that an antagonist of the angiotensin II (Ang II) type 1 (AT1) receptor, losartan, protects dopaminergic (DA) neurons against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxicity both in primary ventral mesencephalic (VM) cultures as well as in the substantia nigra pars compacta (SNpc) of C57BL/6 mice (Fig. 1).

Results

In the presence of exogenous Ang II, losartan reduced MPP+ (5 μM) induced DA neuronal loss by 72% in vitro. Mice challenged with MPTP showed a 62% reduction in the number of DA neurons in the SNpc and a 71% decrease in tyrosine hydroxylase (TH) immunostaining of the striatum, whereas daily treatment with losartan lessened MPTP-induced loss of DA neurons to 25% and reduced the decrease in striatal TH+ immunostaining to 34% of control.

Conclusion

Our study demonstrates that the brain-RAS plays an important neuroprotective role in the MPTP model of PD and points to AT1 receptor as a potential novel target for neuroprotection.  相似文献   
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The most important cause of developing hereditary breast cancer is germline mutations occurring in breast cancer (BCs) susceptibility genes, for example, BRCA1, BRCA2, TP53, CHEK2, PTEN, ATM, and PPM1D. Many BC susceptibility genes can be grouped into two classes, high- and low-penetrance genes, each of which interact with multiple genes and environmental factors. However, the penetrance of genes can also be represented by a spectrum, which ranges between high and low. Two of the most common susceptibility genes are BRCA1 and BRCA2, which perform vital cellular functions for repair of homologous DNA. Loss of heterozygosity accompanied by hereditary mutations in BRCA1 or BRCA2 increases chromosomal instability and the likelihood of cancer, as well as playing a key role in stimulating malignant transformation. With regard to pathological features, familial breast cancers caused by BRCA1 mutations usually differ from those caused by BRCA2 mutations and nonfamilial BCs. It is essential to acquire an understanding of these pathological features along with the genetic history of the patient to offer an individualized treatment. Germline mutations in BRCA1 and BRCA2 genes are the main genetic and inherited factors for breast and ovarian cancer. In fact, these mutations are very important in developing early onset and increasing the risk of familial breast and ovarian cancer and responsible for 90% of hereditary BC cases. Therefore, according to the conducted studies, screening of BRCA1 and BRCA2 genes is recommended as an important marker for early detection of all patients with breast or ovarian cancer risk with family history of the disease. In this review, we summarize the role of hereditary genes, mainly BRCA1 and BRCA2, in BC.  相似文献   
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Plant Cell, Tissue and Organ Culture (PCTOC) - Ziziphora persica (Lamiaceae) has been used as infusions and decoctions in traditional medicine for various purposes such as sedative, carminative,...  相似文献   
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Exhausted T cells and regulatory T (Treg) cells have been recently proposed to be new risk factors for recurrent miscarriage (RM). Intravenous immunoglobulin G (IVIG) treatment reported to modulate various immune cells. In this study, the effects of IVIG on the frequency and function of exhausted T cells, exhausted Tregs, and Treg cells, as well as pregnancy outcome in women with unexplained RM (URM), were investigated. Ninety-four pregnant women with RM were enrolled. At the time of positive pregnancy, blood samples were drawn. Forty-four patients with URM were included as IVIG receiving treated group and received 400 mg/kg of IVIG and the rest fifty patients were considered as a control group and received no IVIG administration. IVIG was given intravenously every 4 weeks during 32 weeks of gestation. Blood samples of patients were collected after the latest administration. Exhausted T cells, exhausted Tregs, and Treg cells were evaluated pre- and posttreatment in both groups. IVIG induced a significant decrease in the frequency of exhausted Tregs population and function as well as a significant increase in Treg cells population, however, IVIG failed to affect population and the function of exhausted T cells. Pregnancy outcome was successful in IVIG treated women (86.3%) and were significantly different (P = 0.0006) in compared with the untreated URM subjects (42%). Therefore, employing of IVIG increases Treg cells and diminishes exhausted Tregs responses in RM patients with cellular immune anomalies throughout the pregnancy. Immunemodulatory effects of IVIG are probably associated with successful pregnancy outcome.  相似文献   
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Ionizing radiation plays a central role in several medical and industrial purposes. In spite of the beneficial effects of ionizing radiation, there are some concerns related to accidental exposure that could pose a threat to the lives of exposed people. This issue is also very critical for triage of injured people in a possible terror event or nuclear disaster. The most common side effects of ionizing radiation are experienced in cancer patients who had undergone radiotherapy. For complete eradication of tumors, there is a need for high doses of ionizing radiation. However, these high doses lead to severe toxicities in adjacent organs. Management of normal tissue toxicity may be achieved via modulation of radiation responses in both normal and malignant cells. It has been suggested that treatment of patients with some adjuvant agents may be useful for amelioration of radiation toxicity or sensitization of tumor cells. However, there are always some concerns for possible severe toxicities and protection of tumor cells, which in turn affect radiotherapy outcomes. Selenium is a trace element in the body that has shown potent antioxidant and radioprotective effects for many years. Selenium can potently stimulate antioxidant defense of cells, especially via upregulation of glutathione (GSH) level and glutathione peroxidase activity. Some studies in recent years have shown that selenium is able to mitigate radiation toxicity when administered after exposure. These studies suggest that selenium may be a useful radiomitigator for an accidental radiation event. Molecular and cellular studies have revealed that selenium protects different normal cells against radiation, while it may sensitize tumor cells. These differential effects of selenium have also been revealed in some clinical studies. In the present study, we aimed to review the radiomitigative and radioprotective effects of selenium on normal cells/tissues, as well as its radiosensitive effect on cancer cells.  相似文献   
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