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191.
192.
Organolead halide perovskite materials have demonstrated great potential in the solar cells field owing to their excellent optoelectronic properties. However, the instability issue of the perovskites impedes the translation of their attractive features for the solar fuel production such as photoelectrochemical H2 production from water splitting. Herein, CH3NH3PbI3 a photocathode with a sandwich‐like structure is fabricated with a general and scalable approach toward addressing this issue. The photocathode exhibits an onset potential at 0.95 V versus reversible hydrogen electrode (RHE) and a photocurrent density of ?18 mA cm?2 at 0 V versus RHE with an impressive ideal ratiometric power‐saved efficiency of 7.63%. More impressively, the photocathode retains good stability under 12 h continuous illumination in water at wide pH range. This performance is much superior to that of the best perovskite‐based photoelectrode ever reported.  相似文献   
193.
Vγ9Vδ2 T cells are a minor subset of lymphocytes in the peripheral blood that has been extensively investigated for their tolerability, safety and anticancer efficacy. A hindrance to the broad application of these cells for adoptive cellular immunotherapy has been attaining clinically appropriate numbers of Vγ9Vδ2 T cells. Furthermore, Vγ9Vδ2 T cells exist at low frequencies among cancer patients. We, therefore, sought to conceive an economical method that allows for a quick and robust large-scale expansion of Vγ9Vδ2 T cells. A two-step protocol was developed, in which peripheral blood mononuclear cells (PBMCs) from healthy donors or cancer patients were activated with Zometa and interleukin (IL)-2, followed by co-culturing with gamma-irradiated, CD64-, CD86- and CD137L-expressing K562 artificial antigen-presenting cells (aAPCs) in the presence of the anti-CD3 antibody OKT3. We optimized the co-culture ratio of K562 aAPCs to immune cells, and migrated this method to a G-Rex cell growth platform to derive clinically relevant cell numbers in a Good Manufacturing Practice (GMP)-compliant manner. We further include a depletion step to selectively remove αβ T lymphocytes. The method exhibited high expansion folds and a specific enrichment of Vγ9Vδ2 T cells. Expanded Vγ9Vδ2 T cells displayed an effector memory phenotype with a concomitant down-regulated expression of inhibitory immune checkpoint receptors. Finally, we ascertained the cytotoxic activity of these expanded cells by using nonmodified and chimeric antigen receptor (CAR)–engrafted Vγ9Vδ2 T cells against a panel of solid tumor cells. Overall, we report an efficient approach to generate highly functional Vγ9Vδ2 T cells in massive numbers suitable for clinical application in an allogeneic setting.  相似文献   
194.
Human glandular kallikrein (KLK2) is a highly prostate-specific serine protease, which is mainly excreted into the seminal fluid, but part of which is also secreted into circulation from prostatic tumors. Since the expression level of KLK2 is elevated in aggressive tumors and it has been suggested to mediate the metastasis of prostate cancer, inhibition of the proteolytic activity of KLK2 is of potential therapeutic value. We have previously identified several KLK2-specific linear peptides by phage display technology. Two of its synthetic analogs, A R R P A P A P G (KLK2a) and G A A R F K V W W A A G (KLK2b), show specific inhibition of KLK2 but their sensitivity to proteolysis in vivo may restrict their potential use as therapeutic agents. In order to improve the stability of the linear peptides for in vivo use, we have prepared cyclic analogs and compared their biological activity and their structural stability. A series of cyclic variants with cysteine bridges were synthesized. Cyclization inactivated one peptide (KLK2a) and its derivatives, while the other peptide (KLK2b) and its derivatives remained active. Furthermore, backbone cyclization of KLK2b improved significantly the resistance against proteolysis by trypsin and human plasma. Nuclear magnetic resonance studies showed that cyclization of the KLK2b peptides does not make the structures more rigid. In conclusion, we have shown that backbone cyclization of KLK2 inhibitory peptides can be used to increase stability without losing biological activity. This should render the peptides more useful for in vivo applications, such as tumor imaging and prostate cancer targeting.  相似文献   
195.
Length–weight (TL vs WWT) and chelae length–width (ChL vs ChW) relationships were described for juveniles, males and females, and for form I and form II males of Procambarus acutus acutus. The length–weight relationships for juveniles, form I, form II males, and females could be described as: WWT = 5 × 10−3 TL3.09, WWT = 6 × 10−3 TL3.61, WWT = 6 × 10−9 TL3.26, and WWT = 6 × 10−4 TL3.5, respectively. In all forms, growth was allometric (P < 0.05). The ancova test indicated that slopes and intercepts of the length–weight regressions were significantly different between sex and sexual stages. The regressions for chelae length–width relationships for form I and form II males, and females were: ChW = −0.81 + 0.27CL, ChW = −0.33 + 0.25CL, and ChW = −0.82 + 0.32CL, respectively. Although the slope and intercepts of regressions for ChL and ChW were similar for those of form I and form II males, the slopes and intercepts of regressions of females were significantly different from form I and form II males. No statistical difference was observed in mean ChL between form II males and females (P > 0.05), but a significant difference was detected in mean ChL between form I and form II males (P < 0.05) and form I and females (P < 0.05). Form I males had longer ChL than form II males and females. The same trend was observed in mean ChW for form I and form II males, but a significant difference was detected between form II males and females (P < 0.05). In addition, results indicated that chelae lengths and widths increased allometrically with total length (TL) for both sex and sexual stages.  相似文献   
196.
Receptor-like cytoplasmic kinases (RLCKs) belong to a large subgroup of kinases that play pivotal roles in plant development and in protecting plants from various stresses. Here, we report the isolation and characterization of rice OsRLCK102, from the OsRLCK VII subgroup. Silencing of OsRLCK102 compromised receptor kinase XA21-mediated resistance to Xanthomonas oryzae pv. oryzae (Xoo) but did not affect plant basal resistance to Xoo or Magnaporthe oryzae (M. oryzae). Plants with silenced OsRLCK102 exhibit architecture alterations, including reduced plant height, enlarged angle of the lamina joint, decreased rates of seed setting and enhanced sensitivity to hormone brassinolide (BR). Collectively, our study reveals that OsRLCK102 positively regulates XA21-mediated immunity and negatively regulates rice development through BR signaling in rice.  相似文献   
197.
Receptor‐like cytoplasmic kinases (RLCKs) represent a large family of proteins in plants. However, few RLCKs have been well characterized. Here, we report the functional characterization of four rice RLCKs – OsRLCK57, OsRLCK107, OsRLCK118 and OsRLCK176 from subfamily VII. These OsRLCKs interact with the rice brassinosteroid receptor, OsBRI1 in yeast cell, but not the XA21 immune receptor. Transgenic lines silenced for each of these genes have enlarged leaf angles and are hypersensitive to brassinolide treatment compared to wild type rice. Transgenic plants silenced for OsRLCK57 had significantly fewer tillers and reduced panicle secondary branching, and lines silenced for OsRLCK107 and OsRLCK118 produce fewer seeds. Silencing of these genes decreased Xa21 gene expression and compromised XA21‐mediated immunity to Xanthomonas oryzae pv. oryzae. Our study demonstrates that these OsRLCKs negatively regulate BR signalling, while positively regulating immune responses by contributing to the expression of the immune receptor XA21.  相似文献   
198.
Fifteen isolates of the biotrophic oomycete Peronospora parasitica (downy mildew) were obtained from a population of Arabidopsis thaliana plants that established naturally in a garden the previous year. They exhibited phenotypic variation in a set of 12 Arabidopsis accessions that suggested that the parasite population consisted of at least six pathotypes. One isolate, Maks9, elicited an interaction phenotype of flecking necrosis and no sporulation (FN) in the Arabidopsis accession Nd-1, and more extensive pitting necrosis with no sporulation (PN) in the accession Ws-2. RPP13 was designated as the locus for a single dominant resistance gene associated with the resistance in Nd-1 and mapped to an interval of approximately 60 kb on a bacterial artificial chromosome (BAC) contig on the lower arm of chromosome 3. This locus is approximately 6 cM telomeric to RPP1, which was previously described as the locus for the PN interaction with five Peronospora isolates, including resistance to Maks9 in Ws-2. New Peronospora isolates were obtained from four other geographically distinct populations of P. parasitica. Four isolates were characterized that elicited an FN phenotype in Nd-1 and mapped resistance to the RPP13 locus. This suggests that the RPP13 locus contains either a single gene capable of multiple isolate recognition or a group of tightly linked genes. Further analysis suggests that the RPP11 gene in the accession Rld-0 may be allelic to RPP13 but results in a different recognition capability.  相似文献   
199.
200.
目的:研究雨生红球藻对长时间、大强度运动导致的大鼠运动性心肌损伤的保护作用。方法:以大强度耐力训练大鼠为模型,将65只42 d龄雄性SPF级Wistar大鼠随机分为5组:安静组(C组)、运动对照组(M组)、运动+雨生红球藻低剂量组(HM I组)、运动+雨生红球藻中剂量组(HM Ⅱ组)、运动+雨生红球藻高剂量组(HM Ⅲ组),每组12只(剔除不符合实验要求的大鼠5只)。雨生红球藻组剂量分别为0.067,0.133,0.4 g/kg,体积为5 ml/kg,每天灌胃(ig)1次,其他组ig等量生理盐水。游泳训练42 d后,测定血清谷丙转氨酶(ALT)等心肌损伤标志物含量、心肌超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量,血清、心肌内皮素(ET)及降钙素基因相关肽(CGRP)含量等相关生化指标。结果:血清ALT、乳酸脱氢酶(LDH)、肌酸激酶(CK)、a-羟丁酸脱氢酶(a-HBDH)、心肌MDA、血清与心肌ET含量,M组较C组显著升高(P<0.05或P<0.01)。心肌SOD活性、血清与心肌CGRP含量,M组较C组显著降低(P<0.05)。血清ALT (P<0.01)、LDH (P<0.01)、CK (P<0.05或P<0.01)含量,HM各组较M组均有所降低,组间无差异,且随剂量增加而递减。血清a-HBDH、ET、心肌ET含量,HM各组较M组均有所降低(P<0.05或P<0.01),且组间随剂量增加而递减;HM Ⅲ组较HM I组显著降低(P<0.05)。心肌MDA含量,HM各组较M组均显著降低(P<0.05或P<0.01),且组间随剂量增加而递减;HM Ⅱ、HM Ⅲ低于HM I组(P<0.01)。心肌SOD活性,HM各组较M组均有所升高(P<0.05或P<0.01),且组间随剂量增加而递增;HM Ⅱ、HM Ⅲ高于HM I组(P<0.01)。血清与心肌CGRP含量,HM各组较M组显著升高(P<0.05或P<0.01),且各组组间随剂量增加而递增;HM Ⅲ组较HM I组显著升高(P<0.05)。结论:不同剂量雨生红球藻可有效地清除机体长时间、大强度运动产生的过量自由基;提高机体免疫力,增强血管cNOS活性,保证ET和CGRP浓度的相对平衡,从而阻止心肌脂质过氧化作用和心肌损伤。其中以高剂量组效果为最好。  相似文献   
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