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151.
Plant Ecology - Due to its contribution to plant drought tolerance, arbuscular mycorrhizae (AM) may play an important role in the revegetation of degraded pastures in semi-arid and arid regions....  相似文献   
152.
Nowadays, alpha‐2‐macroglobulin (A2M) gene has allocated escalating interest among several genes involved in the pathogenesis of avascular necrosis of the femoral head (ANFH). This molecule could interact with several osteogenic‐related proteins. It was reported that adrenocorticotropic hormone (ACTH) affects bones through its receptor located on osteoblasts, suggesting it as a potential target in ANFH treatment. In this study, the effect of ACTH on A2M expression was investigated in osteoblasts as well as during the differentiation of human mesenchymal stem cells (MSCs) into osteoblasts. In this study, MSCs derived from bone marrow were isolated and purified using Ficoll gradient and several passaging. MSCs were characterized by induction with osteogenic and adipogenic medium followed by Oil Red O, Alizarin Red and alkaline phosphatase staining. Besides, MSCs were exposed to various concentrations of ACTH to evaluate the cell variability by MTT assay. MSCs and differentiated osteoblasts were treated with 10?8 molar ACTH for 16 and 26 days, respectively. Then, the total RNA was extracted and A2M expression was quantified by real‐time qPCR. The protein expression levels of osteoblast markers including alkaline phosphatase (ALPL) and bone gamma‐carboxyglutamate protein (BGLAP) were also measured. The results showed that A2M expression in cells treated with ACTH was up‐regulated significantly compared to the control group. Similarly, the expression of osteoblast gene markers including ALPL and BGLAP was significantly increased. ACTH, as an osteoblastic differentiation enhancer, up‐regulates A2M, which promotes osteoblastic differentiation probably through TGF‐β induction.  相似文献   
153.

Background

Soy and red clover isoflavones are controversial due to purported estrogenic activity and possible effects on breast cancer. We conducted a systematic review of soy and red clover for efficacy in improving menopausal symptoms in women with breast cancer, and for potential impact on risk of breast cancer incidence or recurrence.

Methods

We searched MEDLINE, Embase, the Cochrane Library, and AMED from inception to March 2013 for human interventional or observational data pertaining to the safety and efficacy of soy and red clover isoflavones in patients with or at risk of breast cancer.

Results

Of 4179 records, we included a total of 131 articles: 40 RCTs, 11 uncontrolled trials, and 80 observational studies. Five RCTs reported on the efficacy of soy for hot flashes, showing no significant reductions in hot flashes compared to placebo. There is lack of evidence showing harm from use of soy with respect to risk of breast cancer or recurrence, based on long term observational data. Soy intake consistent with that of a traditional Japanese diet (2-3 servings daily, containing 25-50mg isoflavones) may be protective against breast cancer and recurrence. Human trials show that soy does not increase circulating estradiol or affect estrogen-responsive target tissues. Prospective data of soy use in women taking tamoxifen does not indicate increased risk of recurrence. Evidence on red clover is limited, however existing studies suggest that it may not possess breast cancer-promoting effects.

Conclusion

Soy consumption may be associated with reduced risk of breast cancer incidence, recurrence, and mortality. Soy does not have estrogenic effects in humans. Soy intake consistent with a traditional Japanese diet appears safe for breast cancer survivors. While there is no clear evidence of harm, better evidence confirming safety is required before use of high dose (≥100mg) isoflavones can be recommended for breast cancer patients.  相似文献   
154.
Because the question "is AMP-activated protein kinase (AMPK) alpha(2)-isoform a friend or a foe in the protection of the myocardium against ischemia-reperfusion injury?" is still in debate, we studied the functional consequence of its deletion on the contractility, the energetics, and the respiration of the isolated perfused heart and characterized the response to low-flow ischemia and reperfusion with glucose and pyruvate as substrates. alpha(2)-AMPK deletion did not affect basal contractility, respiration, and high-energy phosphate contents but induced a twofold reduction in glycogen content and a threefold reduction in glucose uptake. Low-flow ischemia increased AMPK phosphorylation and stimulated glucose uptake and phosphorylation in both alpha(2)-knockout (alpha(2)-KO) and wild-type (WT) groups. The high sensitivity of alpha(2)-KO to the development of ischemic contracture was attributed to the constitutive impairment in glucose transport and glycogen content and not to a perturbation of the energy transfer by creatine kinase (CK). The functional coupling of MM-CK to myofibrillar ATPase and the CK fluxes were indeed similar in alpha(2)-KO and WT. Low-flow ischemia impaired CK flux by 50% in both strains, showing that alpha(2)-AMPK does not control CK activity. Despite the higher sensitivity to contracture, the postischemic contractility recovered to similar levels in both alpha(2)-KO and WT in the absence of fatty acids. In their presence, alpha(2)-AMPK deletion also accelerated the contracture but delayed postischemic contractile recovery. In conclusion, alpha(2)-AMPK is required for a normal glucose uptake and glycogen content, which protects the heart from the development of the ischemic contracture, but not for contractile recovery in the absence of fatty acids.  相似文献   
155.
Russian Journal of Bioorganic Chemistry - This work describes facile routes towards the synthesis of some novel thiophene derivatives. Thus, condensation of thiophene-2-carboxaldehyde with...  相似文献   
156.
Although remarkable results have been attained by adoptively transferring T cells expressing fully murine and/or humanized anti-CD19 chimeric antigen receptors (CARs) to treat B cell malignancies, evidence of human anti-mouse immune responses against CARs provides a rationale for the development of less immunogenic CARs. By developing a fully human CAR (huCAR), these human anti-mouse immune responses are likely eliminated. This, perhaps, not only increases the persistence of anti-CD19 CAR T cells—thereby reducing the risk of tumor relapse—but also facilitates administration of multiple, temporally separated doses of CAR T cells to the same recipient. To these ends, we have designed and constructed a second-generation fully human anti-CD19 CAR (or huCAR19) containing a fully human single-chain variable fragment (ScFv) fused with a CD8a hinge, a 4-1BB transmembrane domain and intracellular T cell signaling domains of 4-1BB and CD3z. T cells expressing this CAR specifically recognized and lysed CD19+ target cells produced cytokines and proliferated in vitro. Moreover, cell volume data revealed that our huCAR construct cannot induce antigen-independent tonic signaling in the absence of cognate antigen. Considering our results, our anti-CD19 huCAR may overcome issues of transgene immunogenicity that plague trials utilizing CARs containing mouse-derived ScFvs. These results suggest that this huCAR19 be safely and effectively applied for adaptive T cell immunotherapy in clinical practice.  相似文献   
157.
158.
Journal of Plant Growth Regulation - The aim of this study was to investigate metabolite changes, antioxidant capacity and the anatomic features of two cotton seed genotypes (Latif and Golestan)...  相似文献   
159.
160.

The present work reports the As, Cr, Cu, Pb, Zn, and Fe concentrations of drinking water samples in Neyshabur Plain, Iran. This study aimed also to ascertain the potential consumers’ health risk of heavy metal intake. Heavy metal concentrations were analyzed by inductively coupled plasma optical emission spectrometry. The highest and lowest average values in the analyzed water samples were observed for Fe (9.78 ± 5.61 μg/L) and As (1.30 ± 2.99 μg/L), respectively. These values were well below the limits recommended by the World Health Organization and the Iranian national standard. Heavy metal pollution index and heavy metal evaluation index were used to evaluate drinking water quality. The risk index was calculated by chronic daily intake and hazard quotient according to the United States Environmental Protection Agency approach. Heavy metal pollution index in all the samples was less than 100, indicating that it is a low-level heavy metal. The total risk of all heavy metals in the urban environment varied from 40.164 × 10−7 to 174.8 × 10−7. In this research, the maximum average of risk belonged to lead and copper with the respective values of 60.10 × 10−7and 33.99 × 10−7 from the selected wells. However, considering the toxic effect of some elements, including Pb and As, in the chronic exposure of consumers, we suggest a continuous evaluation and monitoring of drinking water resources.

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