RESUMO
The spectrin-based membrane skeleton is a ubiquitous membrane-associated two-dimensional cytoskeleton underneath the lipid membrane of metazoan cells. Mutations of skeleton proteins impair the mechanical strength and functions of the membrane, leading to several different types of human diseases. Here, we report the cryo-EM structures of the native spectrin-actin junctional complex (from porcine erythrocytes), which is a specialized short F-actin acting as the central organizational unit of the membrane skeleton. While an α-/ß-adducin hetero-tetramer binds to the barbed end of F-actin as a flexible cap, tropomodulin and SH3BGRL2 together create an absolute cap at the pointed end. The junctional complex is strengthened by ring-like structures of dematin in the middle actin layers and by patterned periodic interactions with tropomyosin over its entire length. This work serves as a structural framework for understanding the assembly and dynamics of membrane skeleton and offers insights into mechanisms of various ubiquitous F-actin-binding factors in other F-actin systems.
Assuntos
Citoesqueleto , Eritrócitos , Animais , Humanos , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Citoesqueleto/metabolismo , Eritrócitos/citologia , Eritrócitos/metabolismo , Espectrina/análise , Espectrina/metabolismo , SuínosRESUMO
A series of studies have confirmed the relationship between circular RNAs (circRNAs) and metabolic diseases. Hsa_circ_0006260 has been reported to be lowly expressed in the placenta of gestational diabetes mellitus (GDM) patients, but the underlying mechanism and its biological functions remain obscure. Placental tissues were collected from 37 pregnant women with normal glucose tolerance (NGT) and 37 pregnant women with GDM. Expression changes of hsa_circ_0006260 in placentas and high glucose (HG)-stimulated HTR-8/SVneo cells were detected using real-time quantitative polymerase chain reaction. Cell viability and migration were determined by cell counting and transwell assays, respectively. Measurement of cytokines was done by enzyme-linked immunosorbent assay. Cell apoptosis was estimated by flow cytometry assay. The molecular mechanisms were identified using dual-luciferase reporter and RNA-binding protein immunoprecipitation assays. Hsa_circ_0006260 expression was remarkably lowered in GDM patient-derived placentas and HG-stimulated HTR-8/SVneo cells. Functionally, hsa_circ_0006260 overexpression weakened HG-mediated repression of HTR-8/SVneo cell viability and migration, as well as promotion of HTR-8/SVneo cell inflammatory response and apoptosis. Mechanistically, hsa_circ_0006260 functioned as a miR-770-5p decoy to mediate fibronectin type III domains containing protein 5 (FNDC5) expression. Ectopic expression of miR-770-5p weakened hsa_circ_0006260 overexpression-mediated repression of HG-induced HTR-8/SVneo cell dysfunction. Also, FNDC5 knockdown lessened miR-770-5p overexpression-mediated promotion of HG-induced HTR-8/SVneo cell dysfunction. Our findings manifested a novel mechanism by which hsa_circ_0006260 could lower HG-induced HTR-8/SVneo cell dysfunction by upregulating FNDC5 via binding to miR-770-5p, which shed new light on circRNA mediated GDM pathogenesis.
RESUMO
Fenvalerate (FEN), a pyrethroid insecticide used worldwide, has been shown to produce a potentially adverse effect on male reproduction. However the mechanisms are not completely understood. Thus this study aimed to (1) determine whether cellular apoptosis was involved in FEN-induced testicular damage in rats, and (2) identify the potential mechanism involved in FEN-induced apoptosis in testes. Data demonstrated that FEN markedly decreased serum testosterone levels, increased the inner diameter of seminiferous tubules, decreased the layers of spermatogenic cells, disturbed spermatogenesis and increased the number of apoptotic cells. Further, bioinformatic analysis of gene microarray in rat testis tissue showed that FEN significantly altered the expressions of genes (Krt8, Mal, Cd24, Lcn2, Phlda1, Arg2) related to apoptotic related processes. The expression pattern of these 6 genes was upregulated in FEN-treated rat testicular tissue. qRT-PCR analysis demonstrated that Phlda1, a well-documented pro-apoptotic factor, was significantly elevated by FEN. The expression of PHLDA1 testicular protein was also elevated following FEN exposure. In conclusion, our results suggest that FEN exposure induced deleterious effects on rat testes associated with Phlda1-mediated apoptosis which may act as a molecular mechanism underlying FEN induced rat testicular damage.
Assuntos
Proteínas Reguladoras de Apoptose/genética , Apoptose/efeitos dos fármacos , Inibidores Enzimáticos/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Nitrilas/toxicidade , Piretrinas/toxicidade , Testículo/efeitos dos fármacos , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Testículo/metabolismoRESUMO
PURPOSE: Through the study of economic, traffic and population data related to road traffic accidents from 2004 to 2016, this paper analyzed the impact of various factors on road traffic casualties in China, and provided theoretical basis and suggestions for the road traffic safety management in China. METHODS: Based on three aspects (economy, road, population) with five factors (gross domestic product (GDP), traffic investment, new vehicle ownership, new road mileage and newly increased population), this paper collected the relevant data of road traffic accidents in 31 provinces and cities in China, from 2004 to 2016. A panel model was established to carry out empirical analysis. RESULTS: All factors have a significant impact on the number of road traffic accident casualties. When other factors remain unchanged, the number of road traffic casualties decreased by an average of 0.19 for every 100 million CNY increased in GDP. For every 100 million CNY increased in traffic investment, the number of road traffic casualties is reduced by an average of 13.93, indicating that economic development can improve road traffic safety to a certain extent. On the contrary, the growth in road mileage, new motor vehicles and population has increased the number of road traffic casualties. For every 10, 000 km of new road mileage, the number of traffic accident casualties has increased by 284.04. For every 10,000 newborns, the number of road traffic casualties increased by 7.33; as the number of new motor vehicles increases by 10,000, the number of road traffic casualties increased by an average of 21.77. CONCLUSION: The increase of GDP and traffic investment can significantly reduce the number of road traffic casualties in China, which shows that economic development is essential to improve road traffic safety. The numbers of new road mileage, newly increased population and the new motor vehicles are positively correlated with the number of traffic accident casualties in traffic accidents, which reflects the existing problems in road design, distribution of road resources, and traffic management in China. Therefore, it is necessary to improve the economic and road related aspects to improve road traffic safety.
Assuntos
Acidentes de Trânsito/prevenção & controle , Acidentes de Trânsito/estatística & dados numéricos , Economia , Veículos Automotores/estatística & dados numéricos , População , Gestão da Segurança , China/epidemiologia , Planejamento Ambiental , HumanosRESUMO
PURPOSE: By studying the economic data related to road traffic accidents in recent 10 years, this paper explores the impact of various economic factors on the number of casualties in traffic accidents in China, and puts forward related prevention and management measures. METHODS: Based on five economic factors including the number of new health institutions, health investment, transportation investment and disposable income per capita, this paper collects the data of traffic accidents in 31 provinces and municipalities of China from 2004 to 2016 and estimates the parameters using fixed effect model. RESULTS: The number of health institutions, health investment, transportation investment and disposable income per capita are negatively correlated with the number of traffic accident casualties; the number of new health institutions is positively correlated with the number of traffic accident casualties; health investment and transportation investment have a great impact on the number of road traffic accident casualties. CONCLUSION: Economic development has a positive impact on improving traffic conditions, but the increase in the number of new health institutions does not reduce the number of casualties in accidents. The irrational layout of health institutions and imperfect road traffic management mechanism should be taken into account.
Assuntos
Acidentes de Trânsito/mortalidade , Acidentes de Trânsito/prevenção & controle , Economia , Instalações de Saúde/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Acidentes de Trânsito/estatística & dados numéricos , China/epidemiologia , Saúde/economia , Humanos , Renda , Fatores de Tempo , Meios de Transporte/economiaRESUMO
In order to determine the scientificalness of traditionally processed Whitmania pigra, water extraction method and bionic extraction method were used respectively to extract the anticoagulating active components in W. pigra hanging dry products, talcum powder fried products and wine immersing-baked products. Activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT), and antithrombin activity were selected as the activity indexes to evaluate the anticoagulant activities of different processed W. pigra. Then the contents of protein in different processed W. pigra were measured by Coomassie brilliant blue method to preliminarily explain the reason of anticoagulant activity changes. When water extraction method was used, the results of APTT, PT, TT and antithrombin activity showed that the anticoagulant activities of W. pigra were decreased both in talcum powder fried products and wine immersing-baked products, and the activity order was as follows: hanging dried products> wine immersing-baked products>talcum powder fried products. This order was same as the protein content order. While when bionic extraction was used, APTT was shortened in talcum powder fried products, but all the other results indicated the anticoagulant activities of W. pigra processed products were increased, and the activity order was as follows: wine immersing-baked products>talcum powder fried products>hanging dry products. As compared with water extraction, the bionic extraction was more similar to the absorption process of W. pigra in human digestive system after oral administration and was more scientific. Therefore, the traditional processing method can not only modify the taste and smell, but also enhance the anticoagulant activity of W. pigra.
Assuntos
Anticoagulantes/farmacologia , Sanguessugas/química , Animais , Antitrombinas/farmacologia , Biônica , Humanos , Tempo de Tromboplastina Parcial , Tempo de Protrombina , Tempo de Trombina , ÁguaRESUMO
BACKGROUND: Postmastectomy radiotherapy (PMRT), as an important regional treatment, improves the survival rate of patients with T3N0M0 breast cancers. However, the therapeutic effect of PMRT on T3N0M0 patients in different age groups is unclear. METHODS: Using Surveillance, Epidemiology, and End Results database, we identified 4840 T3N0M0 patients between 2000 and 2015. The primary and secondary outcomes were overall survival (OS) and breast cancer-specific survival (BCSS). Survival outcomes were compared using Kaplan-Meier survival test, COX regression analysis, propensity score matching and forest plot, which present the relationship between age and PMRT. RESULTS: Survival analysis demonstrated that for young patients (aged 18-45 and 46-55), there was no significant difference in OS between with and without PMRT. However, for patients older than 65 years, PMRT could significantly improve survival time (P < 0.001). Multivariate Cox analysis of OS showed older patients with PMRT had a lower hazard ratio (HR) than those without PMRT (aged 56-65: HR = 0.67, P = 0.014; aged >65: HR = 0.60, P < 0.001), and little benefit for young patients. The consistent results were also observed in 1:1 matched cohort. Subgroup analysis revealed the survival HRs of with versus without PMRT for patients older than 65 years were significant in most subgroups. CONCLUSION: The effect of PMRT in T3N0M0 patients is related to the age. PMRT is associated with improved survival in older patients with T3N0M0 breast cancer, especially those older than 65 years. While the benefit of PMRT is limited in T3N0M0 patients of young age. The observation suggests the importance of age for T3N0M0 patients when individualized treatment is made.