Foliar Spraying of 6-Benzylaminopurine Promotes Growth and Flavonoid Accumulation in Mulberry (Morus alba L.)

Journal of Plant Growth Regulation - Mulberry (Morus alba L.) leaf, a “source of both medicine and food”, contains antioxidant ingredients such as flavonoids, alkaloids and polyphenols....     

Synthesis and characterization of a photoresponsive doxorubicin/combretastatin A4 hybrid prodrug

To explore the application of photoremovable protecting groups (PPGs) in the field of combination chemotherapy, we designed and synthesized a photoresponsive hybrid prodrug 4 that bearing both doxorubicin (DOX) and combretastatin A4 (CA4). Light triggered drug release investigation found that DOX release was mainly accomplished by 405?nm light while CA4 release was mainly triggered by 365?nm light, i.e., prodrug 4 exhibited a quasi-sequential release behavior when a sequential light irradiation strategy was applied. Cell viability evaluation confirmed the increased cytotoxicity of prodrug 4 compared with individual drugs towards MDA-MB-231cells, indicating that a synergistic effect was achieved.     

Behavioural,physiological and molecular changes in alloparental caregivers may be responsible for selection response for female reproductive investment in honey bees

Reproductive investment is a central life history variable that influences all aspects of life. Hormones coordinate reproduction in multicellular organisms, but the mechanisms controlling the collective reproductive investment of social insects are largely unexplored. One important aspect of honey bee (Apis mellifera) reproductive investment consists of raising female‐destined larvae into new queens by alloparental care of nurse bees in form of royal jelly provisioning. Artificial selection for commercial royal jelly production over 40 years has increased this reproductive investment by an order of magnitude. In a cross‐fostering experiment, we establish that this shift in social phenotype is caused by nurse bees. We find no evidence for changes in larval signalling. Instead, the antennae of the nurse bees of the selected stock are more responsive to brood pheromones than control bees. Correspondingly, the selected royal jelly bee nurses are more attracted to brood pheromones than unselected control nurses. Comparative proteomics of the antennae from the selected and unselected stocks indicate putative molecular mechanisms, primarily changes in chemosensation and energy metabolism. We report expression differences of several candidate genes that correlate with the differences in reproductive investment. The functional relevance of these genes is supported by demonstrating that the corresponding proteins can competitively bind one previously described and one newly discovered brood pheromone. Thus, we suggest several chemosensory genes, most prominently OBP16 and CSP4, as candidate mechanisms controlling queen rearing, a key reproductive investment, in honey bees. These findings reveal novel aspects of pheromonal communication in honey bees and explain how sensory changes affect communication and lead to a drastic shift in colony‐level resource allocation to sexual reproduction. Thus, pheromonal and hormonal communication may play similar roles for reproductive investment in superorganisms and multicellular organisms, respectively.     

Resveratrol protects against isoproterenol induced myocardial infarction in rats through VEGF-B/AMPK/eNOS/NO signalling pathway

According to our previous results, resveratrol (RSV, 3, 5, 4-trihydroxystilbene), a naturally polyphenolic phytoalexin, could attenuate myocardial ischemia/reperfusion injury through up-regulation of vascular endothelial growth factor B (VEGF-B) in isolated rat heart or H9c2 cells. However, the molecular mechanism remains unclear. In this study, we investigated the protective effect of RSV on myocardial infarction (MI) in rats and further explored the underlying signal pathway after VEGF-B. Rats received RSV or normal saline by intragastric administration for 7 consecutive days and followed by subcutaneously isoproterenol (ISO) or normal saline injections for another 2 days. We found that RSV pretreatment prevented the unfavourable changes in HW/BW, HW/TL, infarct size, and cell apoptosis in ISO-treated rats. Moreover, superoxide and malondialdehyde (MDA) production were significantly reduced and superoxide dismutase (SOD) was increased by RSV in ISO-treated rats. Furthermore, it showed that RSV pretreatment increased VEGF-B, p-eNOS and p-AMPK expression, and NO production in ISO-treated rats. Using Neonatal Rat Ventricular Myocytes (NRVM), we found that VEGF-B siRNA could abolish the cardio-protective effect of RSV. The enhanced ratios of eNOS phosphorylation to eNOS expression induced by RSV were markedly reversed by VEGF-B siRNA in NRVM also. Meantime, we found that the effect of VEGF-B knock-down on eNOS activation was rescued by AMPK activator AICAR. L-NAME, a NOS inhibitor, could inhibit RSV enhanced eNOS phosphorylation but had no effect on VEGF-B expression in NRVM or in rats. Collectively, our results indicate that RSV exerts cardio-protection from ISO-induced myocardial infarction through VEGF-B/AMPK/eNOS/NO signalling pathway.     

Integrated Bioinformatics Analysis of DNA Methylation Biomarkers in Thyroid Cancer Based on TCGA Database

Biochemical Genetics - Previous studies have reported a cluster of aberrant promoter methylation changes associated with silencing of tumor suppressor genes in thyroid cancer (TC), but these...     

A phylo-functional core of gut microbiota in healthy young Chinese cohorts across lifestyles,geography and ethnicities

Structural profiling of healthy human gut microbiota across heterogeneous populations is necessary for benchmarking and characterizing the potential ecosystem services provided by particular gut symbionts for maintaining the health of their hosts. Here we performed a large structural survey of fecal microbiota in 314 healthy young adults, covering 20 rural and urban cohorts from 7 ethnic groups living in 9 provinces throughout China. Canonical analysis of unweighted UniFrac principal coordinates clustered the subjects mainly by their ethnicities/geography and less so by lifestyles. Nine predominant genera, all of which are known to contain short-chain fatty acid producers, co-occurred in all individuals and collectively represented nearly half of the total sequences. Interestingly, species-level compositional profiles within these nine genera still discriminated the subjects according to their ethnicities/geography and lifestyles. Therefore, a phylogenetically diverse core of gut microbiota at the genus level may be commonly shared by distinctive healthy populations as functionally indispensable ecosystem service providers for the hosts.     

The Shelterin TIN2 Subunit Mediates Recruitment of Telomerase to Telomeres

Dyskeratosis Congenita (DC) is a heritable multi-system disorder caused by abnormally short telomeres. Clinically diagnosed by the mucocutaneous symptoms, DC patients are at high risk for bone marrow failure, pulmonary fibrosis, and multiple types of cancers. We have recapitulated the most common DC-causing mutation in the shelterin component TIN2 by introducing a TIN2-R282H mutation into cultured telomerase-positive human cells via a knock-in approach. The resulting heterozygous TIN2-R282H mutation does not perturb occupancy of other shelterin components on telomeres, result in activation of telomeric DNA damage signaling or exhibit other characteristics indicative of a telomere deprotection defect. Using a novel assay that monitors the frequency and extension rate of telomerase activity at individual telomeres, we show instead that telomerase elongates telomeres at a reduced frequency in TIN2-R282H heterozygous cells; this recruitment defect is further corroborated by examining the effect of this mutation on telomerase-telomere co-localization. These observations suggest a direct role for TIN2 in mediating telomere length through telomerase, separable from its role in telomere protection.     

NF-κB介导非对称性二甲基精氨酸上调大鼠主动脉诱导型一氧化氮合酶的表达

目的探讨非对称性二甲基精氨酸(ADMA)上调大鼠主动脉诱导型一氧化氮合酶(iNOS)的表达是否是通过激活NF-κB实现的。方法 Wistar大鼠50只随机分为四组:①对照组(n=10):标准饲料喂养。②H组(n=12):高脂饲料喂养。③A+H组(n=14):予ADMA[0.2mg/kgd]灌胃,高脂饲料喂养。④P+A+H组(n=14):予吡咯烷二硫代氨基甲酸盐(pyrrolidine dithiocarbamate,PDTC)[40mg/kgd]腹腔注射、ADMA[0.2mg/kgd]灌胃、高脂饲料喂养。对照组、H组予等体积的生理盐水灌胃及腹腔注射、A+H组给予等体积的生理盐水腹腔注射。18周后麻醉大鼠、取主动脉。以实时荧光定量PCR和Westen blotting分别检测iNOS mRNA和蛋白表达,以电泳迁移率变动分析(EMSA)和增强化学发光法(ECL)检测NF-κB活性。结果①A+H组iNOS mRNA和蛋白表达量较对照组和H组增加(P<0.05),P+A+H组较A+H组iNOSmRNA和蛋白表达量降低(P<0.05)。②A+H组NF-κB活性较对照组和H组显著升高(P<0.05),P+A+H组NF-κB活性较A+H组明显降低(P<0.05)③相关分析:NF-κB活性与iNOS mRNA和蛋白表达量呈正相关(相关系数r分别为0.854、0.876,P<0.05)。结论 ADMA可能通过激活NF-κB途径上调iNOS表达,从而促进动脉粥样硬化的发生发展。