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Since the twenty first century, the outbreaks of global infectious diseases have caused several public health emergencies of international concern, imposing an enormous impact on population health, the economy, and social development. The COVID-19 pandemic has once again exposed deficiencies in existing global health systems, emergency management, and disease surveillance, and highlighted the importance of developing effective evaluation tools. This article outlines current challenges emerging from infectious disease control from the perspective of global health, elucidated through influenza, malaria, tuberculosis, and neglected tropical diseases. The discordance among government actors and absent data sharing platforms or tools has led to unfulfilled targets in health system resilience and a capacity gap in infectious disease response. The current situation calls for urgent action to tackle these threats of global infectious diseases with joined forces through more in-depth international cooperation and breaking governance barriers from the purview of global health. Overall, a systematic redesign should be considered to enhance the resilience of health systems, which warrants a great need to sustain capacity-building efforts in emergency preparedness and response and raises an emerging concern of data integration in the concept of One Health that aims to address shared health threats at the human-animal-environment interface.
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COVID-19 , Enfermedades Transmisibles , Animales , Humanos , Pandemias , Programas de Gobierno , Brotes de Enfermedades , Enfermedades DesatendidasRESUMEN
Negative temperature coefficient (NTC) thermistors feature higher sensitivities and faster response speeds and thereby have particular applications in many fields. However, current NTC thermistors are mostly based on inorganic ceramic materials, which show obvious drawbacks in material synthesis, property modulation, and flexible film fabrication. Herein, we report, for the first time, the promising application of an inorganic-organic hybrid NTC thermistor. A new lead-free hybrid iodo bismuthate [1,1',1â³-(benzene-1,3,5-triyl)tris(3-methyl-1H-imidazol-3-ium)]Bi2I9 [denoted as (Me3TMP)Bi2I9] was synthesized by a "double-free" strategy. (Me3TMP)Bi2I9 features a lead-free binuclear bismuth iodine anion charge compensated by a "classic hydrogen-bond-free" cation. (Me3TMP)Bi2I9 exhibits remarkable stability in water and UV light irradiation and shows the largest temperature sensitivity coefficient among all reported NTC materials. Theoretical calculation and detailed structural analysis disclose that the seriously distorted (BiI6) octahedra are responsible for the intriguing NTC effect for (Me3TMP)Bi2I9.
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Time-resolved fluorescence anisotropy (FA) uses the fluorophore depolarization rate to report on rotational diffusion, conformation changes, and intermolecular interactions in solution. Although FA is a rapid, sensitive, and nondestructive tool for biomolecular interaction studies, the short (â¼ns) fluorescence lifetime of typical dyes largely prevents the application of FA on larger macromolecular species and complexes. By using triplet shelving and recovery of optical excitation, we introduce optically activated delayed fluorescence anisotropy (OADFA) measurements using sequential two-photon excitation, effectively stretching fluorescence anisotropy measurement times from the nanosecond scale to hundreds of microseconds. We demonstrate this scheme for measuring slow depolarization processes of large macromolecular complexes, derive a quantitative rate model, and perform Monte Carlo simulations to describe the depolarization process of OADFA at the molecular level. This setup has great potential to enable future biomacromolecular and colloidal studies.
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BACKGROUND: The detection rate of methylated Septin9 (mSEPT9) in colorectal cancer (CRC) is varied greatly across the studies. This study aimed to evaluate the diagnostic ability of mSEPT9 in CRC, and compare the diagnostic efficacy with fecal immunochemical test (FIT). METHODS: 326 subjects from four centers were prospectively recruited, including 179 CRC and 147 non-CRC subjects. The plasma was collected for mSEPT9 and CEA, AFP, CA125, CA153 and CA199 test, and fecal samples for FIT tests. Sensitivity, specificity and area under the curve (AUC) of receiver operating characteristic curve were calculated to evaluate the diagnostic value of each biomarker. RESULTS: The positive rate in mSEPT9 and FIT, and the level of CEA, CA125 and CA199 were significantly higher in CRC compared with non-CRC subjects. The mSEPT9 positive rate was not associated with TNM stage and tumor stage. The sensitivity, specificity and AUC of mSEPT9 in diagnostic CRC were 0.77, 0.88 and 0.82, respectively, while the value in FIT was 0.88, 0.80 and 0.83, respectively. mSEPT9 and FIT have higher AUC value than that of CEA, CA125 and CA199. Combination of both mSEPT9 and FIT positive increased sensitivity and AUC to 0.98 and 0.83, respectively, but the specificity was declined. mSEPT9 has a slightly low sensitivity in diagnosis of colon cancer (0.87) compared with rectal cancer (0.93). CONCLUSION: mSEPT9 demonstrated moderate diagnostic value in CRC detection, which was similar to the FIT but superior to the CEA, CA125 and CA199. Combination of mSEPT9 and FIT further improved diagnostic sensitivity in CRC. TRIAL REGISTRATION: ChiCTR2000038319.
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Neoplasias Colorrectales , Septinas , Biomarcadores de Tumor , Antígeno Carcinoembrionario , China , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/patología , Detección Precoz del Cáncer , Humanos , Septinas/genética , Septinas/metabolismoRESUMEN
Social hierarchy is associated with various phenotypes. Although memory is known to be important for hierarchy formation, the difference in memory abilities between dominant and subordinate individuals remains unclear. In this study, we examined memory performance in mice with different social ranks and found better memory abilities in dominant mice, along with greater long-term potentiation and higher memory-related gene expression in the hippocampus. Daily injection of memory-improving drugs could also enhance dominance. To validate this correlation across species, through inventory, behavioral and event-related potential studies, we identified better memory abilities in preschool children with higher social dominance. Better memory potentially helped children process dominance facial cues and learn social strategies to acquire higher positions. Our study shows a remarkable similarity between humans and mice in the association between memory and social hierarchy and provides valuable insight into social interactions in young animals, with potential implications for preschool education.
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Jerarquia Social , Predominio Social , Animales , Preescolar , Hipocampo , Humanos , Memoria , RatonesRESUMEN
BACKGROUND: Shanghai, as a pilot city of China to achieve the goal of eliminating hepatitis C, its strategy of allocating medical resources is a pressing problem to be solved. This study aims to infer the time-spatial clustering patterns of HCV-infected cases, and grasp the dynamic genotype distribution of HCV, thereby inform elimination strategies of HCV with efficacy and efficiency. METHODS: Reported HCV cases including their demographic information in Shanghai city from 2005 to 2018 were released from the National Infectious Disease Reporting Information System, population data at community scale, geographical layers of hospitals, communities and districts were gathered from former research. Blood samples of HCV-infected individuals were collected during 2014-2018 from 24 sentinel hospitals, HCV-antibody test, qualitative nucleic acid test and NS5B/5'UTR gene amplification were performed accordingly to determine the genotypes of the specimen. Furthermore, global and local spatial self-correlation analysis of both acute and chronic HCV infections were conducted at community scale year by year, then time-spatial clusters of acute and chronic HCV infections and HCV genotype distribution of specimen collected from sentinel hospitals by districts were mapped by using Arcmap10.1. RESULTS: A total of 2631 acute HCV cases and 15,063 chronic HCV cases were reported in Shanghai from 2005 to 2018, with a peak in 2010 and 2017, respectively. The mean age of chronic HCV patients was 49.70 ± 14.55 years, 3.34 ± 0.32 years older than the acute (t = 10.55, P-value < 0.01). The spatial distribution of acute HCV infection formed one primary cluster (Relative Risk = 2.71), and the chronic formed one primary cluster and three secondary clusters with Relative Risk ranged from 1.94 to 14.42, meanwhile, an overlap of 34 communities between acute and chronic HCV clusters were found with time period spans varied from 6 to 12 years. Genotype 1 (N = 257, 49.71%) was the most prevalent HCV genotype in Shanghai, genotype 3 infections have increased in recent years. Baoshan district presented cluster of acute HCV and the highest proportion of genotype 2, Pudong new area was the cluster of chronic HCV and occupied the highest proportion of genotype 3. CONCLUSIONS: Despite the low prevalence of HCV infection, it is still needed to push forward the elimination process in Shanghai, as there is a certain amount of HCV infected people waiting to be treated. The time-spatial clustering patterns and the dynamic of HCV genotype distribution together indicated a changing constitution of different transmission routes of HCV infection, thus, a focused strategy may be needed for high-risk population related to genotype 3 infection like drug users, in addition to an enforcement of the existing measures of preventing the iatrogenic and hematogenic transmission of HCV.
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Hepatitis C Crónica , Hepatitis C , Adulto , China/epidemiología , Genotipo , Hepacivirus/genética , Hepatitis C/epidemiología , Anticuerpos contra la Hepatitis C , Humanos , Persona de Mediana Edad , PrevalenciaRESUMEN
Social hierarchy plays important roles in maintaining social structures. Despite similarity in concept, frameworks of human hierarchy have seldom been investigated in parallel with other animals. Moreover, the importance of subordination in hierarchical formation has been largely underestimated in previous research. Here we established, compared, and investigated hierarchy in children and weanling mice. Temperament assessments suggested that children who are less persistent, low emotional intensity, and withdrew easily were more likely to be subordinate in competitive scenarios independent of task characteristics and interaction experiences. The tube test further showed that conflicts between mice were not resolved by winner approach but by loser withdrawal, which was mainly determined by intrinsic subordinate status regardless of opponents. Our study presents evolutionary conserved hierarchical relationships in young and a critical role of the intrinsic subordinate characteristics in hierarchical determination. These findings provide a new perspective on social interactions with potential implications for preschool education.
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The genus Diaporthe and its anamorph Phomopsis are distributed worldwide in many ecosystems. They are regarded as potential sources for producing diverse bioactive metabolites. Most species are attributed to plant pathogens, non-pathogenic endophytes, or saprobes in terrestrial host plants. They colonize in the early parasitic tissue of plants, provide a variety of nutrients in the cycle of parasitism and saprophytism, and participate in the basic metabolic process of plants. In the past ten years, many studies have been focused on the discovery of new species and biological secondary metabolites from this genus. In this review, we summarize a total of 335 bioactive secondary metabolites isolated from 26 known species and various unidentified species of Diaporthe and Phomopsis during 2010-2019. Overall, there are 106 bioactive compounds derived from Diaporthe and 246 from Phomopsis, while 17 compounds are found in both of them. They are classified into polyketides, terpenoids, steroids, macrolides, ten-membered lactones, alkaloids, flavonoids, and fatty acids. Polyketides constitute the main chemical population, accounting for 64%. Meanwhile, their bioactivities mainly involve cytotoxic, antifungal, antibacterial, antiviral, antioxidant, anti-inflammatory, anti-algae, phytotoxic, and enzyme inhibitory activities. Diaporthe and Phomopsis exhibit their potent talents in the discovery of small molecules for drug candidates.
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Apoptotic chromatin condensation inducer in the nucleus (also referred as Acin1) was first characterized as an RNA-binding protein involved in apoptosis. In later reports, Acin1 was identified as an auxiliary component of the exon junction complex (EJC) which is assembled throughout pre-messenger RNA splicing. In this study, results of whole-transcriptome analyses revealed reduced expressions and reprogrammed splicing profiles of Acin1 transcripts throughout development of brown adipose tissues (BATs) that execute non-shivering thermogenesis in small rodents and infants by consuming lipids. Depletion of endogenous Acin1 isoforms led to activation of brown adipogenic signatures in mouse C3H10T1/2 fibroblasts. Nevertheless, overexpressions of the Acin1-L or Acin1-S isoform exerted discriminative influences on brown adipogenesis and reprogramming of the expression of serine/arginine-rich splicing factor 3 (SRSF3) through an alternative splicing-coupled nonsense-mediated decay mechanism in a sequence-specific manner. Moreover, the Acin1-SRSF3 axis constitutes a regulatory pathway that participates in the brown adipocyte-related splicing network. Taken together, the interplay between accessory EJC components and splicing regulators constitutes an emerging mechanism for differentially manipulating the activity of brown adipogenesis via alternative splicing network.
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Adipogénesis/genética , Tejido Adiposo Pardo/metabolismo , Empalme Alternativo , Regulación de la Expresión Génica , Proteínas Nucleares/genética , Transcripción Genética , Animales , Mapeo Cromosómico , Biología Computacional/métodos , Perfilación de la Expresión Génica , Ratones , Modelos Biológicos , Anotación de Secuencia Molecular , Isoformas de Proteínas/genética , Activación TranscripcionalRESUMEN
(1) Background: Along with an increasing risk caused by migrant workers returning to the urban areas for the resumption of work and production and growing epidemiological evidence of possible transmission during the incubation period, a study of Coronavirus Disease 2019 (COVID-19) is warranted among key populations to determine the serum antibody against the SARS-CoV-2 and the carrying status of SARS-CoV-2 to identify potential asymptomatic infection and to explore the risk factors. (2) Method: This is a cross-sectional seroepidemiologic study. Three categories of targeted populations (close contacts, migrant workers who return to urban areas for work, and school children) will be included in this study as they are important for case identification in communities. A multi-stage sampling method will be employed to acquire an adequate sample size. Assessments that include questionnaires and blood, nasopharyngeal specimens, and feces collection will be performed via home-visit survey. (3) Ethics and Dissemination: The study was approved by the Institute Review Board of School of Public Health, Fudan University (IRB#2020-04-0818). Before data collection, written informed consent will be obtained from all participants. The manuscripts from this work will be submitted for publication in quality peer-reviewed journals and presented at national or international conferences.
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COVID-19/epidemiología , Estudios Seroepidemiológicos , Migrantes , COVID-19/sangre , Prueba Serológica para COVID-19 , Niño , China/epidemiología , Estudios Transversales , Humanos , Proyectos de Investigación , Tamaño de la MuestraRESUMEN
Internationally, vaccine pricing is relatively opaque, although many low- or lower-middle-income countries belong to international consortiums that jointly procure vaccines. China procures vaccines domestically, and vaccines that require payment from the public ("category 2 vaccines"), have undergone several regulatory changes over the past 15 years. This study aims to describe the vaccine procurement method changes in China since 2005 and to analyze how the procurement method impacted vaccine price. This review of vaccine procurement reforms found that a shift to provincial-level Group Purchasing Organizations after 2016 was accompanied by an increase in most prices. There was more variability in vaccine prices across provinces for vaccines with only one supplier, and these vaccines have a higher price than what is found in United Nations Children's Fund (UNICEF)-supported countries. China's current procurement system for non-mandatory vaccines leaves these vaccines costing several-fold more than in other countries, and in particular those supported by Gavi, the Vaccine Alliance. Exploring a variety of methods to reduce vaccine purchase prices will not only directly benefit the general population, but also the government, as they aim to implement more programs to benefit public health in a cost-effective manner.
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BACKGROUND: A hepatitis E (HepE) vaccine was developed and released in China in 2011. Uptake is currently very limited. The aims of this study were to characterize what public health professionals thought about promoting the HepE vaccine in Shanghai, China, and to develop realistic goals for the HepE vaccine based on this information. METHODS: Public health professionals from Shanghai and other jurisdictions of China were contacted to participate in in-depth qualitative interviews between October 2017 and August 2018. Participants were asked about their perception of the HepE vaccine roll-out. Codes were initially based on the structure of the questionnaire. Subsequently, similar ideas were further developed into themes based on what was present in the transcript data. RESULTS: Thirty-five individuals participated. Major topics of discussion included (1) clarifying the roles and responsibilities of private and public institutions in promoting and marketing the HepE vaccine, (2) identifying what methods of promotion were most efficient, and, (3) endeavoring to formulate a reasonable and realistic goal, if any, for HepE prevention and control in China. Participants emphasized that public sector sources can be trusted sources of information (although the private vaccination company can also be useful in disseminating information) and social media such as WeChat can be good ways to disseminate articles (although netizens may be worried about the spread of fake news). Vaccine promotion is restrained given limited levels of knowledge in the government, hospitals, and public health vaccination centers. CONCLUSION: Successful promotion and use of this vaccine in China, even in limited settings (for instance, certain workplaces, or certain groups) could provide additional information on long-term safety and could promote its adoption in other regions of the world where HepE has high morbidity among pregnant women and other populations.
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Personal de Salud , Promoción de la Salud , Hepatitis E/prevención & control , Vacunas contra Hepatitis Viral/uso terapéutico , China , Hospitales , Humanos , Programas de Inmunización , Difusión de la Información , Sector Privado , Sector Público , Medios de Comunicación Sociales , Encuestas y CuestionariosRESUMEN
Eukaryotes have evolved a specific strategy to package DNA. The nucleosome is a 147-base-pair DNA segment wrapped around histone core proteins that plays important roles regulating DNA-dependent biosynthesis and gene expression. Chromatin remodeling complexes (RSC, Remodel the Structure of Chromatin) hydrolyze ATP to perturb DNA-histone contacts, leading to nucleosome sliding and ejection. Here, we utilized tethered particle motion (TPM) experiments to investigate the mechanism of RSC-mediated nucleosome remodeling in detail. We observed ATP-dependent RSC-mediated DNA looping and nucleosome ejection along individual mononucleosomes and dinucleosomes. We found that nucleosome assembly protein 1 (Nap1) enhanced RSC-mediated nucleosome ejection in a two-step disassembly manner from dinucleosomes but not from mononucleosomes. Based on this work, we provide an entire reaction scheme for the RSC-mediated nucleosome remodeling process that includes DNA looping, nucleosome ejection, the influence of adjacent nucleosomes, and the coordinated action between Nap1 and RSC.
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Ensamble y Desensamble de Cromatina , Proteínas de Unión al ADN/metabolismo , Eucariontes/genética , Proteína 1 de Ensamblaje de Nucleosomas/metabolismo , Nucleosomas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/metabolismo , Adenosina Trifosfato/metabolismo , ADN/metabolismo , Histonas/metabolismoRESUMEN
Low- and middle-income countries receive limited guidance from external entities about how to introduce vaccines. This is especially true for the Hepatitis E (HepE) vaccine, which is currently only commercially available in China. The aims of this qualitative study are to identify which attributes of the HepE disease and vaccine are considered important, and to compare desired promotion methods between different stakeholders. Stakeholders included experts (Centers for Disease Control and Prevention staff, health care providers, and researchers), and nonexperts included members of high-risk populations, HepE cases, and vaccinees. Participants' thoughts were coded and broadly summarized. We contacted 63 persons-35 experts and 28 nonexperts. Safety and effectiveness (but not price) of the vaccine, along with severity of disease and transmission route of infection, were all listed as important attributes. Emphasizing the importance of sharing stories from cases, relying on personal experiences, staying away from statistical explanations, and using the government as a source of promotion were other points repeatedly raised by the participants. Qualitative interviews with experts and nonexperts has revealed that focusing on attributes of disease severity and susceptibility to infection, as well as vaccine safety and effectiveness within stories of cases, are preferred ways to promote the vaccine.
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Tamoxifen resistance is a serious problem in the endocrine therapy of breast cancer. Long non-coding RNAs play important roles in tumor development. In this study, we revealed the involvement of lncRNA uc.57 and its downstream gene BCL11A in TAM resistance. Tamoxifen-resistant MCF-7R cells showed lower expression of uc.57 and higher expression of BCL11A mRNA and protein than the parental MCF-7 cells. Moreover, levels of uc.57 mRNA were lower and BCL11A mRNA were higher in breast cancer tissues than in precancerous breast tissues. Shikonin treatment reduced tamoxifen resistance in MCF-7R cells both in vitro and in vivo, targeting uc.57/BCL11A. Fluorescence in situ hybridization and RNA immunoprecipitation analyses showed that uc.57 binds to BCL11A. Uc.57 overexpression downregulated BCL11A and reduced tamoxifen resistance in MCF-7R cells both in vitro and in vivo. BCL11A knockdown also reduced tamoxifen resistance by inhibiting PI3K/AKT and MAPK signaling pathways. It thus appears shikonin reduces tamoxifen resistance of MCF-7R breast cancer cells by inducing uc.57, which downregulates BCL11A to inhibit PI3K/AKT and MAPK signaling pathways.
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Long non-coding RNAs (lncRNAs) are transcripts longer than 200 bp with no protein-coding capacity. Transcribed ultraconserved regions (T-UCRs) are a type of lncRNA and are conserved among human, chick, dog, mouse and rat genomes. These sequences are involved in cancer biology and tumourigenesis. Nevertheless, the clinical significance and biological mechanism of T-UCRs in breast cancer remain largely unknown. The expression of uc.38, a T-UCR, was down-regulated in both breast cancer tissues and breast cancer cell lines. However, uc.38 was expressed at significantly lower levels in larger tumours and tumours of more advanced stages. Based on the results of in vitro and in vivo experiments, up-regulation of uc.38 expression inhibited cell proliferation and induced cell apoptosis. Thus, uc.38 suppressed breast cancer. Additional experiments revealed that uc.38 negatively regulated the expression of the pre-B-cell leukaemia homeobox 1 (PBX1) protein and subsequently affected the expression of Bcl-2 family members, ultimately inducing breast cancer cell apoptosis. Describing the uc.38/PBX1 axis has improved our understanding of the molecular mechanisms involved in breast cancer apoptosis and has suggested that this axis is a potential therapeutic target for breast cancer.
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Alternative splicing (AS) is a pivotal mechanism for the expansion of gene diversity, which determines the cellular fate or specification. However, the effect of AS networks on brown adipogenesis has not been comprehensively investigated. In this study, we identified the discriminative splicing profiles of RNA-binding motif protein 4a-knockout (RBM4a-/-) brown adipocytes (BAs) and compared them with those of their wild-type counterparts through deep RNA-sequencing. Among these candidates, RBM4a ablation enhanced the relative level of exon 4-excluded neuro-oncological ventral antigen 1 (Nova1-4) transcripts, which were predominantly generated in embryonic BAs. By contrast, most of the Nova1 transcripts were exon 4-included (Nova1+4) in mature BAs. The Nova1 isoforms exhibited differential effects on repressing the development of BAs. Moreover, overexpression of Nova1 proteins reduced the serine/arginine splicing factor 6 (SRSF6) level by enhancing the generation of intron 2-included (SRSF6+intron 2) transcripts, which are a putative candidate of the AS-coupled nonsense-mediated decay mechanism. Furthermore, we observed the positive effect of SRSF6 on BA development. These results highlight the hierarchical role of RBM4a in an AS cascade that manipulates brown adipogenesis.
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Adipocitos/metabolismo , Tejido Adiposo Pardo/citología , Empalme Alternativo , Fosfoproteínas/genética , Proteínas de Unión al ARN/genética , Factores de Empalme Serina-Arginina/genética , Animales , Línea Celular , Masculino , Ratones , Ratones Noqueados , Antígeno Ventral Neuro-OncológicoRESUMEN
RNA-binding motif protein 4a (RBM4a) reportedly reprograms splicing profiles of the insulin receptor (IR) and myocyte enhancer factor 2C (MEF2C) genes, facilitating the differentiation of brown adipocytes. Using an RNA-sequencing analysis, we first compared the gene expressing profiles between wild-type and RBM4a(-/-) brown adipocytes. The ablation of RBM4a led to increases in the PTBP1, PTBP2 (nPTB), and Nova1 proteins, whereas elevated RBM4a reduced the expression of PTBP1 and PTBP2 proteins in brown adipocytes through an alternative splicing-coupled nonsense-mediated decay mechanism. Subsequently, RBM4a indirectly shortened the half-life of the Nova1 transcript which was comparatively stable in the presence of PTBP2. RBM4a diminished the influence of PTBP2 in adipogenic development by reprogramming the splicing profiles of the FGFR2 and PKM genes. These results constitute a mechanistic understanding of the RBM4a-modulated splicing cascade during the brown adipogenesis.
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Adipocitos Marrones/metabolismo , Adipogénesis/fisiología , Diferenciación Celular/fisiología , Empalme del ARN/fisiología , Proteínas de Unión al ARN/metabolismo , Adipocitos Marrones/citología , Animales , Ribonucleoproteínas Nucleares Heterogéneas/biosíntesis , Ribonucleoproteínas Nucleares Heterogéneas/genética , Ratones , Ratones Noqueados , Proteínas del Tejido Nervioso/biosíntesis , Proteínas del Tejido Nervioso/genética , Antígeno Ventral Neuro-Oncológico , Proteína de Unión al Tracto de Polipirimidina/biosíntesis , Proteína de Unión al Tracto de Polipirimidina/genética , Proteínas de Unión al ARN/biosíntesis , Proteínas de Unión al ARN/genéticaRESUMEN
A huge amount of information is stored in genomic DNA and this stored information resides inside the nucleus with the aid of chromosomal condensation factors. It has been reported that the repeat nucleosome core particle (NCP) consists of 147-bp of DNA and two copies of H2A, H2B, H3 and H4. Regulation of chromosomal structure is important to many processes inside the cell. In vivo, a group of histone chaperones facilitate and regulate nucleosome assembly. How NCPs are constructed with the aid of histone chaperones remains unclear. In this study, the histone chaperone-mediated nucleosome assembly process was investigated using single-molecule tethered particle motion (TPM) experiments. It was found that Asf1 is able to exert more influence than Nap1 and poly glutamate acid (PGA) on the nucleosome formation process, which highlights Asf1's specific role in tetrasome formation. Thermodynamic parameters supported a model whereby energetically favored nucleosomal complexes compete with non-nucleosomal complexes. In addition, our kinetic findings propose the model that histone chaperones mediate nucleosome assembly along a path that leads to enthalpy-favored products with free histones as reaction substrates.
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Proteínas de Ciclo Celular/metabolismo , Chaperonas Moleculares/metabolismo , Proteína 1 de Ensamblaje de Nucleosomas/metabolismo , Nucleosomas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Ciclo Celular/química , Chaperonas Moleculares/química , Proteína 1 de Ensamblaje de Nucleosomas/química , Nucleosomas/química , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/químicaRESUMEN
BACKGROUND: In China, caregivers of chronic viral hepatitis patients experience considerable burdens, stress and disruption of their own well-being and social activities. Measurement of the effect on caregivers is an under-researched area. The Family Burden Interview Schedule (FBIS) was primarily devised for the caregivers of schizophrenia patients, and the adverse effect of the disease was similar to the effect of chronic viral hepatitis on family caregivers. In this study, we prospectively evaluated the psychometric properties of FBIS in the field of chronic viral hepatitis and used it to determine the factors affecting the caregiver burden on the family members of chronic viral hepatitis patients in Shanghai, China. METHODS: A representative sample of patients (n = 1478) and caregivers (n = 1478) was randomly obtained through a multi-stage cluster sampling in Shanghai, China. Reliability and validity tests were used to verify the psychometric properties of the instrument. The two-level random intercept model was applied to determine the factors of the caregiver burden between the household and the community level. RESULTS: Cronbach's alpha coefficient was 0.90 for the overall instrument with statistical significance. Factor analysis suggested a three-factor model for the FBIS and confirmed that the adjusted unidimensional model and the second-order multidimensional model had better fit statistics. The average score of the caregiver burden in Shanghai was 12.62 ± 10.74, and financial burden constituted the major effect. The two-level random intercept model demonstrated that the risk factors were hospitalisation (ß 1.69, 95%CI 0.48 to 2.90), elevated serum alanine aminotransferase levels (ß 1.05, 95%CI 0.15 to 1.95), HCV infection (ß 4.49, 95%CI 1.22 to 7.77), and acceptance of the hepatitis B vaccine (ß 2.20, 95%CI 0.56 to 3.85), whereas the protective factors were no consumption of alcohol (ß -2.69, 95%CI -5.19 to -0.19), average monthly costs for patients less than or equal to 100 US dollars (ß -2.96, 95%CI -5.83 to -0.09), and good health status of family caregivers (ß -9.91, 95%CI -12.76 to -7.05). CONCLUSIONS: FBIS can accurately measure the caregiver burden for chronic hepatitis. Targeting interventions toward the conditions associated with the caregiver burden is of great importance.