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81.
生态系统服务供需平衡是保障生态安全的基础,将生态系统服务供需作用流动机制融入生态安全格局构建对保障区域生态安全和提升人类生态福祉具有重要意义。基于景观生态学原理,提出耦合生态系统服务供需的生态安全格局构建逻辑方法,以苏南地区为研究区构建了景观生态安全格局和社会生态安全格局。研究结果表明:(1)耦合生态系统服务供需的生态安全格局应以维系区域生态安全和保障区域人类生态福祉为构建目标。其中,生态安全以生态系统服务与生态风险为核心关注对象,人类生态福祉的实现依赖于人类主动获取与生态系统服务流;(2)苏南地区生态系统服务供需间存在错配格局,在此基础上分别识别生态源地与需求源地4247.46km2、1882.16km2,生态廊道与供需廊道1614.02km、1915.82km,生态夹点29处、生态障碍点23处、生态供需节点20处;(3)形成"三区四带两组团"的社会-景观生态安全格局优化布局方案,并在此基础上提出针对性保护修复策略,推动经济-生态空间协同发展。研究可为丰富区域生态安全格局构建理论和方法、推动国土空间优化与管控提供参考借鉴。 相似文献
82.
为深入了解不同大小脉红螺(Rapana venosa)的碳、氮稳定同位素特征,探究其在典型海湾和海岛水域生态系统所处营养位置,于2022年春季和夏季在胶州湾和长岛近海通过拖网和潜水采集160个脉红螺样本,详细分析了不同体长、体重脉红螺的δ13C和δ15N变化,并计算各研究区域的脉红螺核心生态位宽度及相关参数。结果显示,脉红螺δ13C值范围在-22.12‰--16.63‰,四组数据均值为-19.74‰--17.42‰,δ15N值范围在8.77‰-13.48‰,均值为9.64‰-12.81‰,各组数据营养级均值在2.63-3.57;胶州湾春季脉红螺δ13C值与体长、体重呈显著负相关,夏季呈显著正相关,长岛近海区域无明显变化,表明不同季节和不同区域的食物多样性水平存在差异, 胶州湾脉红螺δ13C、δ15N的变化更为突出;两个研究区域δ15N值和营养级与体长、体重呈显著正相关,主要由于脉红螺摄食偏好性差异,较大的脉红螺倾向于摄食高营养级生物,造成营养级较高。此外,胶州湾脉红螺营养级高于长岛近海,表明其15N来源更为广泛。营养生态位总面积、δ15N差值、δ13C差值、校正后标准椭圆面积等评价指标,揭示了不同区域、不同季节的脉红螺稳定同位素营养生态位的显著差异,反映了区域地理位置与食物来源对脉红螺δ13C和δ15N的影响。上述研究结果为近海生态系统食物网的构建提供了重要数据,并为区域生物资源的管理和生态系统修复工作提供了科学支撑。 相似文献
83.
Ashwani Kumar Galina Aglyamova Yun
Young Yim Aaron O Bailey Haley
M Lynch Reid
T Powell Nghi
D Nguyen Zachary Rosenthal Wen-Ning Zhao Yi Li Jianping Chen Shanghua Fan Hubert Lee William
K Russell Clifford Stephan Alfred
J Robison Stephen
J Haggarty Eric
J Nestler Jia Zhou Mischa Machius Gabby Rudenko 《Nucleic acids research》2022,50(16):9548
84.
Wei Lv Wei Jiang Hongmei Luo Qian Tong Xiaoyu Niu Xiao Liu Yang Miao Jingnan Wang Yiwen Guo Jianan Li Xizhen Zhan Yunqing Hou Yaxin Peng Jian Wang Shuhong Zhao Zaiyan Xu Bo Zuo 《Nucleic acids research》2022,50(18):10733
Long noncoding RNAs (lncRNAs) play important roles in the spatial and temporal regulation of muscle development and regeneration. Nevertheless, the determination of their biological functions and mechanisms underlying muscle regeneration remains challenging. Here, we identified a lncRNA named lncMREF (lncRNA muscle regeneration enhancement factor) as a conserved positive regulator of muscle regeneration among mice, pigs and humans. Functional studies demonstrated that lncMREF, which is mainly expressed in differentiated muscle satellite cells, promotes myogenic differentiation and muscle regeneration. Mechanistically, lncMREF interacts with Smarca5 to promote chromatin accessibility when muscle satellite cells are activated and start to differentiate, thereby facilitating genomic binding of p300/CBP/H3K27ac to upregulate the expression of myogenic regulators, such as MyoD and cell differentiation. Our results unravel a novel temporal-specific epigenetic regulation during muscle regeneration and reveal that lncMREF/Smarca5-mediated epigenetic programming is responsible for muscle cell differentiation, which provides new insights into the regulatory mechanism of muscle regeneration. 相似文献
85.
Bo Li YuZhen Ge WeiWei Yan Bin Gong Kun Cao Rui Zhao Chao Li YeWei Zhang YiHeng Jiang Shi Zuo 《Cell proliferation》2022,55(9)
As a member of the deoxyribonuclease 1 family, DNASE1L3 plays a significant role both inside and outside the cell. However, the role of DNASE1L3 in hepatocellular carcinoma (HCC) and its molecular basis remains to be further investigated. In this study, we report that DNASE1L3 is downregulated in clinical HCC samples and evaluate the relationship between its expression and HCC clinical features. In vivo and in vitro experiments showed that DNASE1L3 negatively regulates the proliferation, invasion and metastasis of HCC cells. Mechanistic studies showed that DNASE1L3 recruits components of the cytoplasmic β‐catenin destruction complex (GSK‐3β and Axin), promotes the ubiquitination degradation of β‐catenin, and inhibits its nuclear transfer, thus, decreasing c‐Myc, P21 and P27 level. Ultimately, cell cycle and EMT signals are restrained. In general, this study provides new insight into the mechanism for HCC and suggests that DNASE1L3 can become a considerable target for HCC.Decreased expression of DNASE1L3 is associated with poor prognosis in patients with HCC DNASE1L3 inhibits the proliferation and cell cycle of HCC cells in vitro and promotes the invasion and metastasis of HCC cells DNASE1L3 inhibits the tumorigenicity and metastasis of HCC cells in vivo DNASE1L3 interacts with β‐catenin and promotes its binding to the β‐catenin destroying complex DNASE1L3 interacts with P21 and stabilizes P21 by mediating the deubiquitin activity 相似文献
86.
BackgroundPlanarian has attracted increasing attentions in the regeneration field for its usefulness as an important biological model organism attributing to its strong regeneration ability. Both the complexity of multiple regulatory networks and their coordinate functions contribute to the maintenance of normal cellular homeostasis and the process of regeneration in planarian. The polarity, size, location and number of regeneration tissues are regulated by diverse mechanisms. In this review we summarize the recent advances about the importance genetic and molecular mechanisms for regeneration control on various tissues in planarian.MethodsA comprehensive literature search of original articles published in recent years was performed in regards to the molecular mechanism of each cell types during the planarian regeneration, including neoblast, nerve system, eye spot, excretory system and epidermal.ResultsAvailable molecular mechanisms gave us an overview of regeneration process in every tissue. The sense of injuries and initiation of regeneration is regulated by diverse genes like follistatin and ERK signaling. The Neoblasts differentiate into tissue progenitors under the regulation of genes such as egfr‐3. The regeneration polarity is controlled by Wnt pathway, BMP pathway and bioelectric signals. The neoblast within the blastema differentiate into desired cell types and regenerate the missing tissues. Those tissue specific genes regulate the tissue progenitor cells to differentiate into desired cell types to complete the regeneration process.ConclusionAll tissue types in planarian participate in the regeneration process regulated by distinct molecular factors and cellular signaling pathways. The neoblasts play vital roles in tissue regeneration and morphology maintenance. These studies provide new insights into the molecular mechanisms for regulating planarian regeneration. Genetic and molecular mechanisms for regeneration control on various tissues in planarian. 相似文献
87.
88.
Wei Zhao Lan Yao Min Zhuang Yuan-Long Lin Xiao-Hong Chen Li Wang Bo Song Ya-Shuang Zhao Yun Xiao Feng-Min Zhang Fu-Xiang Wang Hong Ling 《PLoS neglected tropical diseases》2022,16(9)
BackgroundHuman immunodeficiency virus (HIV) and enteric parasite co-infection not only aggravates the clinical symptoms of parasites but also accelerates acquired immunodeficiency syndrome (AIDS) progression. However, co-infection research on men who have sex with men (MSM), the predominant high-risk population of HIV/AIDS in China, is still limited. In this study, we investigated the epidemiology of enteric parasites, risk factors, and associations with clinical significance in an MSM HIV/AIDS population in Heilongjiang Province, northeast China.MethodsWe recruited 308 MSMs HIV/AIDS patients and 199 HIV-negative individuals in two designated AIDS hospitals in Heilongjiang between April 2016 and July 2017. Fresh stool samples were collected. DNA extraction, molecular identification, and genotyping of Cryptosporidium species, Entamoeba histolytica, Cyclospora cayetanensis, Enterocytozoon bieneusi, and Blastocystis hominis were performed. Fourteen diarrhea-related pathogens were examined to exclude the influence of other bacterial pathogens on diarrhea incidence.Results31.5% of MSM HIV/AIDS participants were infected with at least one parasite species, a significantly higher proportion than that found in the HIV-negative individuals (2.5%). E. bieneusi presented the highest prevalence, followed by B. hominis, E. histolytica, Cryptosporidium spp., and C. cayetanensis. Warm seasons were the risk factor for parasitic infections in this population [odds ratio (OR) = 2.6, 95% CI: 1.47–4.57]. In addition, these individuals showed a higher proportion (35.8%) of present diarrhea (PD) compared with men who have sex with women (MSW) with HIV/AIDS (16.7%). The infection proportions of both Cryptosporidium spp. and E. histolytica were significantly higher in the PD. E. bieneusi infection was more prevalent in the historic diarrhea (HD) group. CD4+ T cell counts in the MSM patients with the above three parasites were significantly lower. New species and genotypes were found, and MSM patients had a wider range of species or genotypes.ConclusionsEnteric parasitic infection was prevalent in the MSM HIV/AIDS population, especially in patients with present diarrhea during warm seasons. E. histolytica and B. hominis should also be considered high-risk parasites for opportunistic infections in AIDS patients in addition to Cryptosporidium spp. 相似文献
89.
Yingxin Ma Guobin Mao Weishan Yang Guoqiang Wu Guoqiang Li Xiaoying Li Xin Lin Junnan Lu Shijun Zhao Wei Zhao Junbiao Dai Xian-En Zhang 《中国科学:生命科学英文版》2022,65(9):1894-1897
<正>Dear Editor,Severe acute respiratory syndrome coronavirus 2(SARSCoV-2) was identified as the pathogen causing the coronavirus disease(COVID-19), which sometimes resulted in fatal pneumonia(Hu et al., 2021). SARS-CoV-2 is a biosafety level 3(BSL-3) pathogen, and the requirement for high containment conditions is a bottleneck for basic research on viral biology. 相似文献
90.