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101.
《Endocrine practice》2021,27(12):1225-1231
ObjectiveBone health in older individuals with HIV infection has not been well studied. This study aimed to compare bone mineral density (BMD), trabecular bone score (TBS), and bone markers between HIV-infected men and age- and body mass index (BMI)-matched HIV-uninfected men aged ≥60 years. We investigated the associations of risk factors related to fracture with BMD, TBS, and bone markers in HIV-infected men.MethodsThis cross-sectional study included 45 HIV-infected men receiving antiretroviral therapy and 42 HIV-uninfected men. Medical history, BMD and TBS measurements, and laboratory tests related to bone health were assessed in all the participants. HIV-related factors known to be associated with bone loss were assessed in the HIV-infected men.ResultsThe mean BMD, TBS, and osteopenia or osteoporosis prevalence were similar among the cases and controls. The HIV-infected men had significantly higher mean N-terminal propeptide of type 1 procollagen and C-terminal cross-linking telopeptide of type I collagen levels. Stepwise multiple linear regression analysis demonstrated that low BMI (lumbar spine, P = .015; femoral neck, P = .018; and total hip, P = .005), high C-terminal cross-linking telopeptide of type I collagen concentration (total hip, P = .042; and TBS, P = .010), and low vitamin D supplementation (TBS, P = .035) were independently associated with low BMD and TBS.ConclusionIn older HIV-infected men with a low fracture risk, the mean BMD and TBS were similar to those of the age- and BMI-matched controls. The mean bone marker levels were higher in the HIV group. Traditional risk factors for fracture, including low BMI, high C-terminal cross-linking telopeptide of type I collagen level, and low vitamin D supplementation, were significant predictors of low BMD and TBS.  相似文献   
102.
According Global Cancer Statistics 2020 GLOBOCAN estimates female breast cancer was found as the most commonly diagnosed cancer, with an estimated 2.3 million new cases (11.7%), and the fourth leading cause (6.9%) of cancer death among women worldwide. Identification of new diagnostic marker sharply characterize the tumor feature is intensive need. The present work was performed to investigate the involvement of the INF-γ + 874 T/A gene polymorphism in different breast cancer prognostic factors. Polymorphism detection analysis was performed on 163 subjects from breast cancer patients, 79 with inflamed cells of breast patients and 144 controls. The gene polymorphism was detected using the amplification refractory mutation system- polymerase chain reaction method (ARMS-PCR). The distribution of INF-γ T + 874A gene polymorphism shows strong significant association between INF-γ + 874 T/A genotypes TT in BC patients (ORTT: 6.41 [95% CI = 2.72–15.1] P < 0.0001) as well as strong significant association regarding T allele (ORT: 1.99 [95% CI = 1.43–2.76] P < 0.0001) when compared to the healthy control. In ICB group the strong association was noted with INF-γ + 874 T/A genotypes AT genotype (ORAT: 2.28 [95% CI = 1.22–4.29] P = 0.007). From the different histological BC hormonal markers the human epidermal growth factor receptor 2 (HER2) was showing significant association in INF-γ + 874 T/A genotypes TT (P = 0.03) and recessive model (TT versus AA + AT P = 0.03). Concerning different BC prognostic models, the poor prognostic one of luminal B, (ER+ve PR+ve Her2+ve) show significant association in the host INF-γ + 874 T/A genotype (TT, P = 0.03) and recessive model (TT versus AA + AT P = 0.02) when compared to the good prognostic hormonal status luminal A model, (ER+ve PR+ve Her2-ve). It seems that this is the first study that interested in correlate the INF-γ + 874 T/A gene polymorphisms in Egyptian BC patients. T allele, TT genotype and recessive model of the INF-γ + 874 T/A gene variants were documented as risk factors for BC pathogenesis. It may be used as practical biomarker to guide the BC carcinogenesis and risk process.  相似文献   
103.
Importin β1 (KPNB1) is a nucleocytoplasmic transport factor with critical roles in both cytoplasmic and nucleocytoplasmic transport, hence there is keen interest in the characterization of its subcellular interactomes. We found limited efficiency of BioID in the detection of importin complex cargos and therefore generated a highly specific and sensitive anti-KPNB1 monoclonal antibody to enable biotinylation by antibody recognition analysis of importin β1 interactomes. The monoclonal antibody recognizes an epitope comprising residues 301-320 of human KPBN1 and strikingly is highly specific for cytoplasmic KPNB1 in diverse applications, with little reaction with KPNB1 in the nucleus. Biotinylation by antibody recognition with this novel antibody revealed numerous new interactors of importin β1, expanding the KPNB1 interactome to cytoplasmic and signaling complexes that highlight potential new functions for the importins complex beyond nucleocytoplasmic transport. Data are available via ProteomeXchange with identifier PXD032728.  相似文献   
104.
Plant-derived carbon (C) inputs via foliar litter, root litter and root exudates are key drivers of soil organic C stocks. However, the responses of these three input pathways to climate warming have rarely been studied in alpine shrublands. By employing a 3-year warming experiment (increased by 1.3 °C), we investigated the effects of warming on the relative C contributions from foliar litter, root litter and root exudates from Sibiraea angustata, a dominant shrub species in an alpine shrubland on the eastern Qinghai-Tibetan Plateau. The soil organic C inputs from foliar litter, root litter and root exudates were 77.45, 90.58 and 26.94 g C m−2, respectively. Warming only slightly increased the soil organic C inputs from foliar litter and root litter by 8.04 and 11.13 g C m−2, but significantly increased the root exudate C input by 15.40 g C m−2. Warming significantly increased the relative C contributions of root exudates to total C inputs by 4.6% but slightly decreased those of foliar litter and root litter by 2.5% and 2.1%, respectively. Our results highlight that climate warming may stimulate plant-derived C inputs into soils mainly through root exudates rather than litter in alpine shrublands on the Qinghai-Tibetan Plateau.  相似文献   
105.
Male moths locate conspecific females by pheromone‐induced upwind flight maintained by detecting a visual flow, termed optomotor anemotaxis. Their behavioural pattern is characterized by an upwind surge in response to a pheromone stimulus and crosswind casting after odour loss, which is considered to be reset and restarted on receipt of another pheromone pulse. However, pheromone‐stimulated males of the potato tuberworm moth Phthorimaea operculella exhibit a series of short and straight intermittent flights, or hops, when moving upwind. It is unclear whether they navigate by employing the same behavioural pattern and wind detection mechanism as that used by flying moths. To analyze odour‐modulated anemotaxis in male potato tuberworm moths, a flat wind tunnel is constructed to give regular odour stimuli to an insect regardless of its location. Moths are subjected to pheromone pulses of different frequencies to test whether they show a behavioural pattern that is reset and restarted by a pheromone pulse. Moths on the ground are also subjected to crosswind shear to examine their detection of wind direction. Path analyses reveal that males surge upwind when they receive a pheromone pulse and exhibit casting by successive hops when they lose odour. This behavioural pattern appears to be similar to that of flying moths. When the direction of the airflow is switched orthogonally, males adjust their course angle accordingly when they are on the ground. It is suggested that, instead of optomotor anemotaxis, this ‘aim‐then‐shoot’ system aids the detection of wind direction, possibly by mechanosensory means.  相似文献   
106.
Heterotrimeric G protein is involved in plant growth and development, while the role of rice (Oryza sativa) G protein γ subunit qPE9-1 in response to low-phosphorus (LP) conditions remains unclear. The gene expression of qPE9-1 was significantly induced in rice roots under LP conditions. Rice varieties carrying the qPE9-1 allele showed a stronger primary root response to LP than the varieties carrying the qpe9-1 allele (mutant of the qPE9-1 allele). Transgenic rice plants with the qPE9-1 allele had longer primary roots and higher P concentrations than those with the qpe9-1 allele under LP conditions. The plasma membrane (PM) H+-ATPase was important for the qPE9-1-mediated response to LP. Furthermore, OsGF14b, a 14-3-3 protein that acts as a key component in activating PM H+-ATPase for root elongation, is also involved in the qPE9-1 mediation. Moreover, the overexpression of OsGF14b in WYJ8 (carrying the qpe9-1 allele) partially increased primary root length under LP conditions. Experiments using R18 peptide (a 14-3-3 protein inhibitor) showed that qPE9-1 is important for primary root elongation and H+ efflux under LP conditions by involving the 14-3-3 protein. In addition, rhizosheath weight, total P content, and the rhizosheath soil Olsen-P concentration of qPE9-1 lines were higher than those of qpe9-1 lines under soil drying and LP conditions. These results suggest that the G protein γ subunit qPE9-1 in rice plants modulates root elongation for phosphorus uptake by involving the 14-3-3 protein OsGF14b and PM H+-ATPase, which is required for rice P use.  相似文献   
107.
Comparative two-dimensional electrophoresis showed six proteins, which were significantly produced in the root of salt-tolerant barley. These proteins were identified as stress/defense-related proteins that do not scavenge reactive oxygen species directly, suggesting that salt-tolerant barley develops not only an antioxidative system, but also physical and biochemical changes to cope with salt stress.  相似文献   
108.
白雪  赵成章  康满萍 《生态学报》2021,41(5):1878-1884
根系构型影响根系空间分布和营养吸收效率,反映了植物适应环境胁迫的生存策略。采用标准化主轴估计(Standardized major axis estimation,SMA)的方法,分析了甘肃金塔北海子国家湿地公园3年生和6年生多枝柽柳(Tamarix ramosissima)根系分叉数与分支角度的异速生长关系。结果表明:随着林龄的增长,湿地群落盖度、高度逐渐增加,多枝柽柳种群的盖度、密度、高度和地上生物量以及根系深度、分叉数、比根长、比表面积、各级根系直径随之增加,根系分支角度和根冠比逐渐减小;多枝柽柳根系分叉数与分支角度回归方程的标准主轴斜率逐渐增大(P<0.05),随着林龄的增长,多枝柽柳根系分叉数的增加速度逐渐大于根系分支角度的生长速度,二者在林龄间呈现出差异化的异速生长关系。随着林龄的增长,多枝柽柳根系构型模式由"扩散型"转变为"紧缩型",体现了种群应对生境胁迫和竞争的生态适应机制。  相似文献   
109.
微生物残体是稳定土壤碳库的重要来源,对退化生境碳的固持和积累具有重要意义。植物根系分泌物作为植物-土壤-微生物"交流"的媒介,是调控土壤微生物残体迁移转化的关键。因此,以极度退化草地土壤为对象,以氨基糖为标志物,模拟研究了不同氮浓度(低氮-LN:0.1 gN/kg;高氮-HN:0.2 gN/kg)和多样性(3种化合物、9种化合物)根系分泌物输入对土壤微生物残体的影响。结果表明:(1)根系分泌物输入可显著增加高寒退化草地土壤微生物残体含量,且主要由真菌残体贡献。其中高氮和低多样性处理增加最明显,微生物残体和真菌残体分别增加了101.14%,125.16%,而低氮和高多样性处理微生物残体和真菌残体仅增加了35.79%,33.51%。(2)根系分泌物的输入可增加土壤β-葡萄糖苷酶、土壤磷酸酶和过氧化物酶活性,促进微生物的生长,而降低β-N-乙酰氨基葡萄糖苷酶活性,减少微生物残体的分解。(3)回归分析结果显示,土壤微生物残体与土壤环境的C/N呈显著负相关,与微生物生物量C/N呈显著正相关。上述结果表明,在未来退化草地恢复中,可充分利用模拟根系分泌物输入的土壤固碳策略,即通过提高土壤氮的有效性,促进微生物的生长,加快代谢周转,进一步提高微生物残体含量。  相似文献   
110.
Triphala is a famous triherbal drug, comprising three herb fruits, including Terminalia chebula (Haritaki), Terminalia bellirica (Bibhitaki), and Phyllanthus emblica (Amalaki). It is enriched with vitamin C, polyphenols, flavonoids, sterols, saponins, etc., and is well-documented for its potent antioxidant, anticancer, chemoprotective, antimicrobial, and anti-inflammatory effects. This research was conducted to evaluate the synergistic antioxidative and cytotoxic potential of mixtures of the individual constituents of Triphala at their nonequivalent ratios along with the chemical characterization of individual constituents of Triphala to identify and quantify individual compounds. The antioxidative potential was measured using total antioxidant capacity (TAC), DPPH free radical scavenging assay, and total phenolic content (TPC) tests. The cytotoxic potential was assessed on brain cancer cells (N4X4) using MTT assay, and phytochemical characterization was performed by GS-MS analysis. Nonequivalent ratios of Triphala constituents exhibited significantly higher synergistic antioxidant and cytotoxic potential than the equivalent ratios of them. Moreover, the nonequivalent ratio where the quantity of Amalaki was doubled than the other two constituents showed the highest synergistic antioxidant and cytotoxic effect. GC-MS analysis of individual constituents of Triphala identified and quantified the presence of a wide array of compounds, and fatty acid, fatty acid ester, triterpene, and aminoglycoside remained the predominant class of compounds. Thus, it can be inferred that the observed bioactivities can be attributed to the phytocompounds characterized and extracts at the nonequivalent ratio of Triphala constituents where Amalaki is doubled can be more effective in treating oxidative degenerative diseases and glioblastoma.  相似文献   
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