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721.
Remobilization of stored carbohydrates in the stem of wheat plants is an important contributor to grain filling under drought stress (DS) conditions. A massive screening on Iranian wheat cultivars was performed based on stem dry weight changes under well-watered and DS conditions. Two cultivars, Shole and Crossed Falat Hamun (CFH), with different fructan accumulation and remobilization behavior were selected for further studies. Water-soluble carbohydrates (WSCs) and fructan metabolizing enzymes were studied both in the stem penultimate and in sucrose (Suc) treated, excised leaves. Under drought, CFH produced higher grain yields than Shole (412 vs 220 g m(-2)). Also, grain yield loss under drought was more limited in CFH than in Shole (17 vs 54%). Under drought, CFH accumulated more graminan-type fructo-oligosaccharides than Shole. After anthesis, fructan 6-exohydrolase (6-FEH; EC 3.2.1.154) activities increased more prominently than fructan 1-exohydrolase (EC 3.2.1.153) activities during carbon remobilization. Interestingly, CFH showed higher 6-FEH activities in the penultimate than Shole. The field experiment results suggest that the combined higher remobilization efficiency and high 6-FEH activities in stems of wheat could contribute to grain yield under terminal drought. Similar to the penultimate, fructan metabolism differed strongly in Suc-treated detached leaves of selected cultivars. This suggests that variation in the stem fructan among wheat cultivars grown in the field could be traced by leaf blade induction experiments.  相似文献   
722.
ML-IAP [melanoma IAP (inhibitor of apoptosis)] is an anti-apoptotic protein that is expressed highly in melanomas where it contributes to resistance to apoptotic stimuli. The anti-apoptotic activity and elevated expression of IAP family proteins in many human cancers makes IAP proteins attractive targets for inhibition by cancer therapeutics. Small-molecule IAP antagonists that bind with high affinities to select BIR (baculovirus IAP repeat) domains have been shown to stimulate auto-ubiquitination and rapid proteasomal degradation of c-IAP1 (cellular IAP1) and c-IAP2 (cellular IAP2). In the present paper, we report ML-IAP proteasomal degradation in response to bivalent, but not monovalent, IAP antagonists. This degradation required ML-IAP ubiquitin ligase activity and was independent of c-IAP1 or c-IAP2. Although ML-IAP is best characterized in melanoma cells, we show that ML-IAP expression in normal mammalian tissues is restricted largely to the eye, being most abundant in ciliary body epithelium and retinal pigment epithelium. Surprisingly, given this pattern of expression, gene-targeted mice lacking ML-IAP exhibited normal intraocular pressure as well as normal retinal structure and function. The results of the present study indicate that ML-IAP is dispensable for both normal mouse development and ocular homoeostasis.  相似文献   
723.
The purpose of this study was to investigate the effect of clomiphene citrate and human chorionic gonadotropin (HCG) on the structural changes, as well as the evaluation of the expression of cation channel sperm‐associated protein 1 (CatSper1), cation channel sperm‐associated protein 2 (CatSper2), luteinizing hormone/choriogonadotropin receptor (LHCGR), and steroidogenic factor 1 (SF1) genes in testicular tissue of rats. All rats divided into five groups as follows; G1 as the control group that received normal saline, G2 received olive oil, G3 received 100 IU/kg HCG, G4 received 5 mg/kg clomiphene citrate, and G5 received 5 mg/kg clomiphene citrate and 100 IU/kg HCG. At the end of the experiment period, Day 56, blood samples were taken and the serum was isolated. Then, histomorphometric analysis, hormonal assess, and real‐time polymerase chain reaction to measure the expression of CatSper1, CatSper2, LHCGR, and SF1 genes were performed. The results showed that the concentrations of testosterone, follicle‐stimulating hormone, and luteinizing hormone were decreased in the G4 group, whereas these parameters were increased in the G3 group. A comparison of the sperm quality indicated a significant reduction in the quality of sperm cells in the G4 group compared with other groups. The quality of sperm was significantly enhanced in the G3 and G5 groups in comparison with the G1 group. Also, our findings demonstrated that the expression of CatSper1, CatSper2, LHCGR, and SF1 genes were significantly elevated in the G3 group when compared with other experimental groups. According to the obtained results, it seems that clomiphene citrate reduces the process of spermatogenesis and the detrimental impacts of this compound would be neutralized by the administration of HCG.  相似文献   
724.
Molecular Biology Reports - The coronary artery disease (CAD) is a chronic inflammatory disease caused by atherosclerosis, in which arteries become clogged due to plaque formation, fat...  相似文献   
725.

Metastatic breast cancer remains a serious health concern and numerous investigations recommended medicinal plants as a complementary therapy. Crocin is one of the known anticancer bio-component. Recently, the inhibitory effect of metformin has been studied on the various aspects of cancer. However, no study reported their combination effects on metastatic breast cancer. In the present study, we have assessed their anti-metastatic effects on in vitro and in vivo breast cancer models. Using MTT assay, scratch, and adhesion tests, we have evaluated the cytotoxic, anti-invasive and anti-adhesion effects of crocin and metformin on 4T1 cell line, respectively. Their protective effects and MMP9 as well as VEGF protein expression levels (Western blotting) investigated in the 4T1 murine breast cancer model. Our results showed that both crocin and metformin reduced cell viability, delayed scratch healing and inhibited the cell adhesion, in vitro. While crocin alone restored the mice’s weight reduction, crocin, metformin, and their combination significantly reduced the tumor volume size and enhanced animal survival rate in murine breast cancer model, responses that were associated with VEGF and MMP9 down-regulation. These findings suggest that a combination of crocin and metformin could serve as a novel therapeutic approach to enhance the effectiveness of metastatic breast cancer therapy.

  相似文献   
726.
Mycopathologia - Trichophyton benhamiae is a zoophilic dermatophyte mainly transmitted to humans from guinea pigs. This zoophilic species can also cause dermatophytosis as reported by human contact...  相似文献   
727.
Plant Molecular Biology Reporter - The Arabidopsis RRTF1 promoter is transiently activated by salt stress over 6 hours, before it quickly reverts to pre-stress levels, even if the salt...  相似文献   
728.
Plant Cell, Tissue and Organ Culture (PCTOC) - In this study, various concentrations of oryzalin (0, 5, 10, 50, and 100 mg l?1), trifluralin (0, 5, 10, 50, and...  相似文献   
729.
In Vitro Cellular & Developmental Biology - Plant - Global demands for an in vitro culture of cannabis have never been more sought after as countries shift their paradigm towards legalization....  相似文献   
730.
Plasmonics - Graphene is a single-atom thin layer with sp2 hybridized and two-dimensional (2D) honeycomb structure of carbon. Because of its exclusive properties including high conductivity, high...  相似文献   
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