Niche characteristics of rodents by diverse disturbance in Alashan desert, Inner Mongolia, China

Four diverse disturbance types, namely, farmland, rotationally grazed grassland, overgrazed grassland and forbidden grazing grassland, were identified in the Alashan desert region of Inner Mongolia. Rodents were sampled in April, July and October in 2002 and 2003 using the trap-day method. Their spatial and temporal niches among the four disturbance types were assessed using the Shannon-Wiener niche breadth index and the Pianka niche overlap index. The Shannon-Wiener niche breadth index was the highest for Allactaga sibirica and Meriones meridianus (0.925 and 0.908, respectively), intermediate for Cricetulus eversmanni, Phodopus roborovskii and Citellus dauricus (0.789, 0.782 and 0.711, respectively), and lowest for Cardiocranius paradoxus (0.003). The Pianka niche overlap indices of six-paired species were the highest and varied from 0.900 to 1.000, suggesting their spatial niche overlapped almost completely. Conversely, the spatial niche overlap index for Meriones unguiculatus, Cardiocranius paradoxus, and Salpingotus kozlovi was zero, thus indicating a complete absence of competition among them. In addition, the temporal niche breadth and overlap indices varied greatly in relation to disturbance types and season. The level of temporal niche overlap in spring and autumn was low while in summer it was high. For all disturbance types and for each season, the temporal niche overlap index of Meriones meridianus and Cricetulus barabansis was always highest but for Meriones unguiculatus and Salpingotus kozlovi always lowest. __________ Translated from Acta Ecologica Sinica, 2005, 25(10): 2,637–2,643 [译自: 生态学报]     

韭菜化感物质草莓酸对香蕉枯萎病菌的影响

香蕉枯萎病主要由尖孢镰刀菌 4 号生理小种(Fusarium oxysporum f. sp. cubense,Foc4)引起的一种土传病害,严重威胁香蕉产业的可持续发展。为寻求一种经济有效且环保的防治措施,以韭菜化感物质的衍生物草莓酸(strawberry acid,SA)为材料,通过平板和盆栽实验,研究了SA对Foc4的菌丝生长、香蕉枯萎病病情指数、土壤微生物数量、土壤酶活性的影响。结果表明:(1)随着SA浓度的增加,Foc4的菌落生长直径显著减小,第5天时菌落直径在SA浓度为300、450 μL·L^-1时比150 μL·L^-1分别减小了49.15%、70.89%; 液体培养条件下SA浓度为600 μL·L^-1时Foc4的分生孢子数量显著低于对照处理(相差 470 多倍); pH为5时SA对Foc4的抑制效果显著比pH为7和9时好。(2)随实验处理时间的延长,添加 SA后香蕉幼苗的病情指数显著低于对照。(3)土壤细菌、真菌数量和微生物总量在SA为600 μL·L^-1时均为最高; Foc4数量随SA浓度升高而降低,在1 200 μL·L^-1时显著降低。(4)各土壤酶在浓度(300～600 μL·L^-1)SA处理时活性较高; 1 200 μL·L^-1时显著降低,过氧化氢酶和多酚氧化酶较对照分别降低了41.88%、54.82%。(5)相关性分析得出,土壤微生物总量与细菌、真菌数量极显著正相关; 土壤真菌与放线菌显著负相关; 土壤细菌、真菌和放线菌数量均与蔗糖酶、多酚氧化酶显著正相关; 蔗糖酶与脲酶、过氧化氢酶与多酚氧化酶均显著正相关。综上认为,添加SA浓度为600 μL·L^-1能较好地抑制Foc4的菌丝生长且能提高其抑制率,病情指数明显降低,有利于改善香蕉的生长环境。该研究结果为有效利用SA防治香蕉枯萎病提供了科学依据。     

Circulating exosomal CPNE3 as a diagnostic and prognostic biomarker for colorectal cancer

Exosomal proteins are emerging as relevant diagnostic and prognostic biomarkers for cancer. This study was aimed at illustrating the clinical significance of exosomal Copine III (CPNE3) purified from the plasma of colorectal cancer (CRC) patients. The CPNE3 expression levels in CRC tissues were analyzed by real-time PCR, western blot, and immunohistochemistry. Plasma exosomes were isolated to examine the CPNE3 level using ELISA. Pearson’s correlation analysis was performed to investigate the CPNE3 levels between CRC tissues and matched plasma samples. Receiver operating characteristic curve analysis was developed to measure the diagnostic performance of exosomal CPNE3. The Kaplan–Meier method and Cox's proportional hazards model were utilized to determine statistical differences in survival times. CPNE3 showed increased expressions in the CRC tissues. A moderately significant correlation was found between CPNE3 expression in CRC tissues by immunohistochemistry and matched serum exosomal CPNE3 expression by ELISA (r = 0.645,(r = 0.645, p < 0.001). < 0.001). Exosomal CPNE3 yielded a sensitivity of 67.5% and a specificity of 84.4% in CRC at the cutoff value of 0.143 pg per 1ug1 ug exosome. Combined data from carcinoembryonic antigen and exosomal CPNE3 achieved 84.8% sensitivity and 81.2% specificity as a diagnostic tool. CRC patients with lower exosomal CPNE3 levels had substantially better disease-free survival (hazard ratio [HR], 2.9; 95% confidence interval [CI]: 1.3–6.4; p = 0.009) = 0.009) and overall survival (HR, 3.4; 95% CI: 1.2–9.9; p = 0.026) = 0.026) compared with those with higher exosomal CPNE3 levels. Exosomal CPNE3 show potential implications in CRC diagnosis and prognosis.     

Scutellarin exerts protective effects against atherosclerosis in rats by regulating the Hippo–FOXO3A and PI3K/AKT signaling pathways

Atherosclerosis (AS), a progressive disorder, is one of the tough challenges in the clinic. Scutellarin, an extract from Herba Erigerontis, is found to have oxygen-free radicals scavenging effects and antioxidant effects. In this study, we aimed to investigate the anti-AS effects of scutellarin is related to controlling the Hippo–FOXO3A and PI3K/AKT signal pathway. To establish an AS model, the rats in the scutellarin and model groups were intraperitoneally injected with vitamin D ₃ and then fed a high-fat diet for 12 weeks. In addition, in vitro angiotensin II-induced apoptosis of human aortic endothelial cells (HAECs) were used to establish models. Scutellarin significantly reduced blood lipid levels and increased antioxidase levels in both models. Additionally, scutellarin inhibited reactive oxygen species generation and apoptosis in HAECs. The impaired vascular barrier function was restored by using scutellarin in AS rats and in HAECs cells characterized by inhibiting mammalian sterile-20-like kinases 1 (Mst1) phosphorylation, Yes-associated protein (YAP) phosphorylation, forkhead box O3A (FOXO3A) phosphorylation at serine 207, nuclear translocation of FOXO3A, and upregulating protein expression of AKT and FOXO3A phosphorylation at serine 253. Scutellarin significantly reduced Bcl-2 interacting mediator of cell death (Bim), caspase-3, APO-1, CD95 (Fas), and Bax: Bcl-2-associated X (Bax) levels and activated Bcl-2: B-cell lymphoma-2 (Bcl-2). Scutellarin also significantly inhibited the expression of Mst1, YAP, FOXO3A at the messenger RNA level. When Mst1 was overexpressed or phosphoinositide 3-kinases suppressed, the effects of scutellarin were significantly blocked. In conclusion, the results of the present study suggest that scutellarin exerts protective effects against AS by inhibiting endothelial cell injury and apoptosis by regulating the Hippo–FOXO3A and PI3K/AKT signal pathways.     

Pravastatin sodium attenuated TREM-1-mediated inflammation in human peripheral blood mononuclear cells

Pravastatin sodium on triggering receptor expressed on myeloid cell-1 (TREM-1)-mediated inflammation in human peripheral blood mononuclear cells (PBMCs) has been poorly investigated. In this study, we isolated PBMCs from the peripheral blood samples of patients with chronic obstructive pulmonary disease, treated the cells with pravastatin sodium, and determined a concentration at which more than 90% cells could survive. Then we treated cells with 10?ng/ml of lipopolysaccharide, added with 10, 50, 100?μM of pravastatin sodium combined with or without LR-12, a known TREM-1 inhibitor. The expression of TREM-1 was determined by quantitative RT-PCR. The levels of TREM-1, IL-6, and TNF-α in cell culture supernatant were measured with ELISA. Simultaneously, NF-κB signaling pathway-related protein p-p65 and p-IκBα were detected by Western blot assay. Results demonstrated that pravastatin sodium significantly mitigated lipopolysaccharide-stimulated TREM-1 over-expression at mRNA and protein levels dose-dependently. Elevated IL-6 and TNF-α levels changed synchronously. LR-12 inhibited the TREM-1 over-expression and inflammatory factor production but did not show extra synergistic effect to pravastatin. Lipopolysaccharide induced phospho-p65 and -IκBα over-expression was weakened significantly when cells were treated with pravastatin sodium. In conclusion, pravastatin could inhibit TREM-1-medieted inflammation and NF-κB signaling pathway was involved.     

Role of caveolin-1 in epidermal stem cells during burn wound healing in rats

Local transplantation of stem cells has therapeutic effects on skin damage but cannot provide satisfactory wound healing. Studies on the mechanisms underlying the therapeutic effects of stem cells on skin wound healing will be needed. Hence, in the present study, we explored the role of Caveolin-1 in epidermal stem cells (EpiSCs) in the modulation of wound healing. We first isolated EpiSCs from mouse skin tissues and established stable EpiSCs with overexpression of Caveolin-1 using a lentiviral construct. We then evaluated the epidermal growth factor (EGF)-induced cell proliferation ability using cell counting Kit-8 (CCK-8) assay and assessed EpiSC pluripotency by examining Nanog mRNA levels in EpiSCs. Furthermore, we treated mice with skin burn injury using EpiSCs with overexpression of Caveolin-1. Histological examinations were conducted to evaluate re-epithelialization, wound scores, cell proliferation and capillary density in wounds. We found that overexpression of Caveolin-1 in EpiSCs promoted EGF-induced cell proliferation ability and increased wound closure in a mouse model of skin burn injury. Histological evaluation demonstrated that overexpression of Caveolin-1 in EpiSCs promoted re-epithelialization in wounds, enhanced cellularity, and increased vasculature, as well as increased wound scores. Taken together, our results suggested that Caveolin-1 expression in the EpiSCs play a critical role in the regulation of EpiSC proliferation ability and alteration of EpiSC proliferation ability may be an effective approach in promoting EpiSC-based therapy in skin wound healing.     

Erbin plays a critical role in human umbilical vein endothelial cell migration and tubular structure formation via the Smad1/5 pathway

Angiogenesis is an important process in atherosclerosis. ErbB2 was proved to have an important role in vascular development, but it is still unclear whether Erbin expresses in vessels as well as its location and function in the vessels. In the current study, we investigated the location and function of Erbin in human umbilical veins. The human umbilical veins were prepared, and immunofluorescent analysis was performed to determine the expression of Erbin. Human umbilical vein endothelial cells (HUVECs) were cultured and the lentivirus (LV) containing Erbin RNAi was also prepared. After transfection with the lentivirus, CCK-8 assay and Annexin V-PI assay were used for cell proliferation and apoptosis, respectively. Cell migration was studied using the scratch wound healing assay and the transwell assay. The capillary-like tube formation assay was performed to illustrate the effect of Erbin on HUVEC tube formation. Expression of signaling pathway molecules was assessed with Western blot. The immunofluorescent analysis suggested that Erbin expressed in human umbilical veins and the majority of the Erbin is strongly colocalized in endothelial cells. Although knockdown of Erbin did not affect HUVEC proliferation and apoptosis, it significantly suppressed HUVEC migration and tubular structure formation. Erbin knockdown showed no effect on the ERK1/2 and Smad2/3 signaling pathways but significantly promoted Smad1/5 phosphorylation and nuclear translocation. Ablation of the Smad1/5 pathway decreased the effects of Erbin on endothelial cells. Erbin is mainly localized in endothelial cells in human umbilical veins and plays a critical role in endothelial cell migration and tubular formation via the Smad1/5 pathway.     

FAM83H-AS1 is associated with clinical progression and modulates cell proliferation,migration, and invasion in bladder cancer

FAM83H-AS1, also known as oncogenic long noncoding RNA (lncRNA)-3, is a novel lncRNA that has been suggested to be dysregulated in a variety of human cancers. However, the expression status and function of FAM83H-AS1 in bladder cancer are still unknown. The object of our study is to explore the clinical value of FAM83H-AS1 in patients with bladder cancer and the biological function of FAM83H-AS1 in bladder cancer cells. In our results, the expression of FAM83H-AS1 was obviously elevated in bladder cancer tissue samples and bladder cancer cell lines compared with adjacent normal tissue samples and normal bladder epithelial cell lines, respectively. In addition, high expression of FAM83H-AS1 was associated with advanced clinical stage and the presence of muscularis invasion and served as an independent poor prognostic factor for overall survival in patients with bladder cancer. The loss-of-function study showed that silencing FAM83H-AS1 expression suppressed cell proliferation, migration, and invasion and induced cycle arrest at G0/G1 phase. In conclusion, FAM83H-AS1 is involved in the progression of bladder cancer and serves as a prognostic biomarker and potential therapeutic target for patients with bladder cancer.     

人机共融的主动型下肢假肢分层控制策略探讨

为研究当前主动型下肢假肢控制问题的解决策略,提出了主动型下肢假肢设计和分类的通用控制框架,包括3个分层结构:上层控制器、中层控制器、底层控制器。其中,上层控制器感知运动意图;中层控制器将运动意图转换为预期的装置状态,用于底层控制器的跟踪参考;底层控制器通过反馈控制或者前馈控制计算出预期装置状态与当前装置状态的误差,驱动假肢执行这些命令,形成控制闭环。结果表明,该通用控制框架可完整阐释主动型下肢假肢的人—机—环境共融关系,明确了分层控制策略的层级任务,为未来主动型下肢假肢的发展提供了理论指导。