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1.
PLoS Genet ; 18(4): e1010137, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35421082

RESUMO

Viral infections can alter host transcriptomes by manipulating host splicing machinery. Despite intensive transcriptomic studies on SARS-CoV-2, a systematic analysis of alternative splicing (AS) in severe COVID-19 patients remains largely elusive. Here we integrated proteomic and transcriptomic sequencing data to study AS changes in COVID-19 patients. We discovered that RNA splicing is among the major down-regulated proteomic signatures in COVID-19 patients. The transcriptome analysis showed that SARS-CoV-2 infection induces widespread dysregulation of transcript usage and expression, affecting blood coagulation, neutrophil activation, and cytokine production. Notably, CD74 and LRRFIP1 had increased skipping of an exon in COVID-19 patients that disrupts a functional domain, which correlated with reduced antiviral immunity. Furthermore, the dysregulation of transcripts was strongly correlated with clinical severity of COVID-19, and splice-variants may contribute to unexpected therapeutic activity. In summary, our data highlight that a better understanding of the AS landscape may aid in COVID-19 diagnosis and therapy.


Assuntos
COVID-19 , Processamento Alternativo/genética , COVID-19/genética , Teste para COVID-19 , Humanos , Proteômica , SARS-CoV-2/genética , Transcriptoma
2.
BMC Public Health ; 24(1): 1470, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822308

RESUMO

BACKGROUND: Associations between perceived and actual risk of HIV infection and HIV prevention services uptake are inconclusive. This study aimed to evaluate the discrepancy between the perceived and actual HIV risk, and quantify the associations between perceived and actual risk of HIV infection and three HIV prevention services utilization among men who have sex with men (MSM) in Shandong province, China. METHODS: A cross-sectional study was conducted in Shandong province in June 2021. Participants were eligible if they were born biologically male, aged 18 years or older, had negative or unknown HIV status, and had sex with men in the past year. Participants were recruited online. The discrepancy between their perceived and actual risk of HIV infection was evaluated by calculating the Kappa value. Bayesian model averaging was used to assess the associations between perceived and actual risk of HIV infection and HIV prevention services uptake. RESULTS: A total of 1136 MSM were recruited, most of them were 30 years old or younger (59.9%), single (79.5%), with at least college education level (74.7%). Most participants (97.4%) perceived that they had low risk of HIV infection, and 14.1% were assessed with high actual risk. The discrepancy between their perceived and actual risk of HIV infection was evaluated with a Kappa value of 0.076 (P < 0.001). HIV testing uptake had a weak association with perceived high HIV prevalence among social networks (aOR = 1.156, post probability = 0.547). The perceived high HIV prevalence among national MSM was positive related to willingness to use PrEP (aOR = 1.903, post probability = 0.943) and PEP (aOR = 1.737, post probability = 0.829). Perceived personal risk (aOR = 4.486, post probability = 0.994) and perceived HIV prevalence among social networks (aOR = 1.280, post probability = 0.572) were related to history of using PrEP. Perceived personal risk (aOR = 3.144, post probability = 0.952), actual risk (aOR = 1.890, post probability = 0.950), and perceived risk among social networks (aOR = 1.502, post probability = 0.786) were related to history of using PEP. CONCLUSIONS: There is discordance between perceived and actual personal risk of HIV infection among MSM in China. HIV risk assessment and education on HIV prevalence among MSM should be strengthened to assist high-risk populations aware their risk accurately and hence access HIV prevention services proactively.


Assuntos
Infecções por HIV , Homossexualidade Masculina , Humanos , Masculino , Estudos Transversais , China/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/epidemiologia , Adulto , Homossexualidade Masculina/estatística & dados numéricos , Homossexualidade Masculina/psicologia , Adulto Jovem , Conhecimentos, Atitudes e Prática em Saúde , Adolescente , Pessoa de Meia-Idade , Medição de Risco , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Inquéritos e Questionários
3.
Blood ; 138(5): 401-416, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-33895821

RESUMO

Circulating platelets interact with leukocytes to modulate host immune and thrombotic responses. In sepsis, platelet-leukocyte interactions are increased and have been associated with adverse clinical events, including increased platelet-T-cell interactions. Sepsis is associated with reduced CD8+ T-cell numbers and functional responses, but whether platelets regulate CD8+ T-cell responses during sepsis remains unknown. In our current study, we systemically evaluated platelet antigen internalization and presentation through major histocompatibility complex class I (MHC-I) and their effects on antigen-specific CD8+ T cells in sepsis in vivo and ex vivo. We discovered that both human and murine platelets internalize and proteolyze exogenous antigens, generating peptides that are loaded onto MHC-I. The expression of platelet MHC-I, but not platelet MHC-II, is significantly increased in human and murine platelets during sepsis and in human megakaryocytes stimulated with agonists generated systemically during sepsis (eg, interferon-γ and lipopolysaccharide). Upregulation of platelet MHC-I during sepsis increases antigen cross-presentation and interactions with CD8+ T cells in an antigen-specific manner. Using a platelet lineage-specific MHC-I-deficient mouse strain (B2Mf/f-Pf4Cre), we demonstrate that platelet MHC-I regulates antigen-specific CD8+ T-cell proliferation in vitro, as well as the number and functional responses of CD8+ T cells in vivo, during sepsis. Loss of platelet MHC-I reduces sepsis-associated mortality in mice in an antigen-specific setting. These data identify a new mechanism by which platelets, through MHC-I, process and cross-present antigens, engage antigen-specific CD8+ T cells, and regulate CD8+ T-cell numbers, functional responses, and outcomes during sepsis.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Tolerância Imunológica , Sepse/imunologia , Adulto , Animais , Proliferação de Células , Feminino , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Masculino , Camundongos , Camundongos Knockout , Estudos Prospectivos , Sepse/genética
4.
AIDS Behav ; 27(7): 2205-2215, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36525148

RESUMO

Disclosure of HIV status offers potential benefits to individuals and is also good for public health. Limited studies have been conducted to gain insight into the current situation and associated factors of HIV disclosure among HIV-positive Chinese men who have sex with men (MSM) in the era of "treat all." We carried out a cross-sectional study among MSM receiving antiretroviral therapy from October 2020 to January 2021 at a hospital in Jinan, China. We used univariate and multivariable logistic regression to examine the factors associated with general disclosure and disclosure to family, friends, and sexual partners. Of the 585 participants recruited, 62.2% reported HIV disclosure, among which 25.3% had disclosed their status to family members, 25.3% had disclosed it to friends, and 28.4% had disclosed it to partners. The findings suggest that HIV disclosure is more likely to occur among individuals who are younger, married/cohabiting, and who self-identify as homosexual/bisexual. Participants with higher education levels or personal monthly incomes are less likely to disclose their HIV status. Furthermore, related factors of disclosure vary across the types of disclosure targets. Given the positive outcomes of disclosure, interventions and implementation research to facilitate it are urgently needed for MSM.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Masculino , Humanos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Revelação , Estudos Transversais , Comportamento Sexual , Parceiros Sexuais , China/epidemiologia
5.
Nucleic Acids Res ; 49(4): 1935-1950, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33544864

RESUMO

Long noncoding RNAs (lncRNAs) play a wide range of roles in the epigenetic regulation of crucial biological processes, but the functions of lncRNAs in cortical development are poorly understood. Using human embryonic stem cell (hESC)-based 2D neural differentiation approach and 3D cerebral organoid system, we identified that the lncRNA PAUPAR, which is adjacent to PAX6, plays essential roles in cortical differentiation by interacting with PAX6 to regulate the expression of a large number of neural genes. Mechanistic studies showed that PAUPAR confers PAX6 proper binding sites on the target neural genes by directly binding the genomic regions of these genes. Moreover, PAX6 recruits the histone methyltransferase NSD1 through its C-terminal PST enrichment domain, then regulate H3K36 methylation and the expression of target genes. Collectively, our data reveal that the PAUPAR/PAX6/NSD1 complex plays a critical role in the epigenetic regulation of hESC cortical differentiation and highlight the importance of PAUPAR as an intrinsic regulator of cortical differentiation.


Assuntos
Córtex Cerebral/metabolismo , Células-Tronco Embrionárias/metabolismo , Regulação da Expressão Gênica , Fator de Transcrição PAX6/metabolismo , RNA Longo não Codificante/metabolismo , Sítios de Ligação , Diferenciação Celular/genética , Células Cultivadas , Células-Tronco Embrionárias/citologia , Deleção de Genes , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Humanos , Metilação , Organoides , RNA Longo não Codificante/genética
6.
Small ; 18(19): e2201510, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35388969

RESUMO

The immoderate use of pesticides in the modern agricultural industry has led to the pollution of water resources and ultimately threatens the human body. Herein, two metal-organic frameworks (MOFs), namely {[Zn(tpt)2 ·2H2 O]}n (Zn1) and {[Zn2 (tpt)2 (bdc)]}n (Zn2), (Htpt = 5-[4(1H-1,2,4-triazol-1-yl)]phenyl-2H-tetrazole), respectively, are constructed as smart materials for visual and on-site detection of pesticides and their removal from water. The exposed nitrogen-rich sites and high chemical stability make Zn2 a self-assembly core to further fabricate MOF-on-MOF-sodium alginate (ZIF-8-on-Zn2@SA) composite by wrapping ZIF-8 on the outside surface. Inheriting the excellent fluorescent emission of Zn2, the rod-like ZIF-8-on-Zn2@SA module exhibits naked-eye detection of thiophanate-methyl (TM) in real fruits and vegetables with a broad linear range (10-100 × 10-6  m), a low limit of detection (LOD = 0.14 × 10-6  m), and satisfactory recoveries (98.30-102.70%). In addition, carbendazim (CBZ), the metabolite of TM after usage in crops, can be efficiently removed from water by the ZIF-8-on-Zn2@SA (qmax  = 161.8 mg g-1 ) with a high correlation coefficient (R2  > 0.99). Therefore, the portable ZIF-8-on-Zn2@SA sensing platform presents a promising candidate for monitoring and removal of pesticides, especially suitable for regions with serious pesticide environmental pollution.


Assuntos
Estruturas Metalorgânicas , Praguicidas , Alginatos , Humanos , Hidrogéis , Praguicidas/análise , Água
7.
EMBO Rep ; 21(11): e50283, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33016573

RESUMO

A microdeletion within human chromosome 5q14.3 has been associated with the occurrence of neurodevelopmental disorders, such as autism and intellectual disability, and MEF2C haploinsufficiency was identified as main cause. Here, we report that a brain-enriched long non-coding RNA, NDIME, is located near the MEF2C locus and is required for normal neural differentiation of mouse embryonic stem cells (mESCs). NDIME interacts with EZH2, the major component of polycomb repressive complex 2 (PRC2), and blocks EZH2-mediated trimethylation of histone H3 lysine 27 (H3K27me3) at the Mef2c promoter, promoting MEF2C transcription. Moreover, the expression levels of both NDIME and MEF2C were strongly downregulated in the hippocampus of a mouse model of autism, and the adeno-associated virus (AAV)-mediated expression of NDIME in the hippocampus of these mice significantly increased MEF2C expression and ameliorated autism-like behaviors. The results of this study reveal an epigenetic mechanism by which NDIME regulates MEF2C transcription and neural differentiation and suggest potential effects and therapeutic approaches of the NDIME/MEF2C axis in autism.


Assuntos
Transtorno Autístico , Animais , Transtorno Autístico/genética , Diferenciação Celular , Células-Tronco Embrionárias/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Fatores de Transcrição MEF2/genética , Camundongos , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/metabolismo , Regiões Promotoras Genéticas
8.
BMC Infect Dis ; 22(1): 937, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36514071

RESUMO

BACKGROUND: Research on the relationship between disclosure of HIV status to male sexual partners (HIV disclosure) and quality of life (QOL) revealed complex and even contradictory results. The impact of HIV disclosure on various domains of QOL and the mediation effect between them are unclear. The purposes of this study were to explore the impact of HIV disclosure on QOL among men who have sex with men (MSM), and whether HIV treatment self-efficacy mediated these relationships. METHODS: The data came from a baseline survey on the design of a randomized control trial conducted in Shandong, China. A total of 579 MSM patients were included. SPSS 24.0 was used to conduct independent samples t test, one-way analysis of variance and nonparametric tests and the PROCESS macro was used to conduct mediation analysis. RESULTS: Among 579 participants, 16.06% disclosed their HIV infection status to their male sexual partners. The effect of HIV disclosure on QOL was mediated by treatment self-efficacy. Self-efficacy played partial mediating role in social relationships, meaning that HIV disclosure had both direct and indirect effects on this factor. In the overall QOL and domains of physical, psychological, independence, and environment, HIV disclosure had an indirect effect only through self-efficacy and no significant effect on the spirituality domain. CONCLUSIONS: The results emphasize the importance of HIV disclosure and self-efficacy on the QOL of MSM patients and suggest that health care providers should assist MSM patients in deciding whether to disclose their HIV status during daily medical services.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Humanos , Masculino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/psicologia , Homossexualidade Masculina , Revelação , Qualidade de Vida , Autoeficácia , Parceiros Sexuais , Comportamento Sexual/psicologia
9.
AIDS Res Ther ; 19(1): 55, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36424621

RESUMO

BACKGROUND: Consistent and complete adherence is considered an essential requirement for patients on antiretroviral therapy (ART). This study aimed to evaluate the impact of ART duration on ART adherence, identify the trend of complete adherence, and compare the factors associated with ART adherence between short-term and long-term ART group among men who have sex with men (MSM) living with HIV in Jinan of China. METHODS: MSM living with HIV aged 18 or above and currently on ART were recruited from October to December 2020 using convenience sampling. Univariate and multivariable logistic regressions were used to evaluate the impact of ART duration on adherence and compare factors associated with ART adherence between subgroups. The Mann-Kendall test was used to identify the trend of complete adherence. RESULTS: A total of 585 participants were included in analysis, consisting of 352 on short-term ART (ART initiation ≤ 3 years) and 233 on long-term ART (ART initiation > 3 years). Significant difference of complete ART adherence between short-term and long-term ART group was detected (79.8% vs. 69.1%, P = 0.003). Multivariable analysis showed that men with longer ART duration were less likely to report complete ART adherence (AOR = 0.88, 95% CI 0.81-0.95). A descending trend of complete adherence was identified (Z = 1.787, P = 0.037). Alcohol use and lack of medication reminders were barriers to complete adherence for both of the subgroups. CONCLUSIONS: Sustained efforts to encourage maintaining adherence for a lifetime are necessary, especially for those on long-term ART. Future interventions should be tailored to subgroups with different ART duration and individuals with specific characteristics.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Masculino , Humanos , Infecções por HIV/tratamento farmacológico , Homossexualidade Masculina , Antirretrovirais/uso terapêutico , China/epidemiologia
10.
Am J Physiol Heart Circ Physiol ; 320(5): H1959-H1974, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33769916

RESUMO

In this study, we investigated whether human umbilical cord mesenchymal stem cell (hUCMSC) fibrin patches loaded with nerve growth factor (NGF) poly(lactic-co-glycolic acid) (PLGA) nanoparticles could enhance the therapeutic potency of hUCMSCs for myocardial infarction (MI). In vitro, NGF significantly improved the proliferation of hUCMSCs and mitigated cytotoxicity and apoptosis under hypoxic injury. NGF also promoted the paracrine effects of hUCMSCs on angiogenesis and cardiomyocyte protection. The tyrosine kinase A (TrkA) and phosphoinositide 3-kinase (PI3K)-serine/threonine protein kinase (Akt) signaling pathways in hUCMSCs were involved in the NGF-induced protection. NGF PLGA nanoparticles continued to release NGF for at least 1 mo and also exerted a protective effect on hUCMSCs, the same with free NGF. In vivo, we treated MI mice with nothing (MI group), a cell-free fibrin patch with blank PLGA nanoparticles (MI + OP group), a cell-free fibrin patch with NGF nanoparticles (MI + NGF group), and hUCMSC fibrin patches with blank PLGA nanoparticles (MI + MSC group) or NGF PLGA nanoparticles (MSC + NGF group). Among these groups, the MSC + NGF group exhibited the best cardiac contractile function, the smallest infarct size, and the thickest ventricular wall. The application of NGF PLGA nanoparticles significantly improved the retention of transplanted hUCMSCs and enhanced their ability to reduce myocardial apoptosis and promote angiogenesis in the mouse heart after MI. These findings demonstrate the promising therapeutic potential of hUCMSC fibrin cardiac patches loaded with NGF PLGA nanoparticles.NEW & NOTEWORTHY NGF PLGA nanoparticles can exert a protective effect on hUCMSCs and promote the paracrine effects of hUCMSCs on angiogenesis and cardiomyocyte protection through TrkA-PI3K/Akt signaling pathway, the same with free NGF. The application of NGF PLGA nanoparticles in the hUCMSC fibrin cardiac patches can significantly improve the retention of transplanted hUCMSCs and enhance their ability to reduce myocardial apoptosis and promote angiogenesis in the mouse heart after MI.


Assuntos
Proliferação de Células/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanopartículas/administração & dosagem , Fator de Crescimento Neural/administração & dosagem , Remodelamento Atrial/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor trkA/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Analyst ; 146(20): 6132-6138, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34490859

RESUMO

In this research, we propose a novel microlens surface-enhanced Raman spectroscopy (SERS) substrate @ Au film detection system, which is shown to have excellent attributes. This scheme involves the construction of a PDMS plano-convex microlens SERS-active substrate in combination with an Au film. Due to the optical convergence from the microlens, the synergistic enhancement effects due to the Au film, and the "Au film-molecules-AgNPs" sandwich structure, an outstanding SERS performance is achieved. Multiple tests using a portable Raman spectrometer show that the optical convergence due to the microlens and the coupling effects contribute around 1.85× and 26.18× enhancement of the Raman signal, respectively. Even for objective lenses with different numerical apertures, simulations show that the microlens SERS substrate can further enhance the signal collection efficiency; this indicates that the detection scheme is universally applicable. Moreover, the microlens SERS substrate @ Au film system shows excellent time stability, and its Raman enhancement performance remains consistently above 98% of the original signal, even one week later. Our proposed system is simple to prepare, is low cost and has many potential practical applications, which include the detection of biochemical samples.


Assuntos
Ouro , Nanopartículas Metálicas , Análise Espectral Raman
12.
Nucleic Acids Res ; 46(8): 3906-3920, 2018 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-29529255

RESUMO

Previous studies have revealed the critical roles of N6-methyladenosine (m6A) modification of mRNA in embryonic stem cells (ESCs), but the biological function of m6A in large intergenic noncoding RNA (lincRNA) is unknown. Here, we showed that the internal m6A modification of linc1281 mediates a competing endogenous RNA (ceRNA) model to regulate mouse ESC (mESC) differentiation. We demonstrated that loss of linc1281 compromises mESC differentiation and that m6A is highly enriched within linc1281 transcripts. Linc1281 with RRACU m6A sequence motifs, but not an m6A-deficient mutant, restored the phenotype in linc1281-depleted mESCs. Mechanistic analyses revealed that linc1281 ensures mESC identity by sequestering pluripotency-related let-7 family microRNAs (miRNAs), and this RNA-RNA interaction is m6A dependent. Collectively, these findings elucidated the functional roles of linc1281 and its m6A modification in mESCs and identified a novel RNA regulatory mechanism, providing a basis for further exploration of broad RNA epigenetic regulatory patterns.


Assuntos
Adenosina/análogos & derivados , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Adenosina/química , Adenosina/metabolismo , Animais , Sequência de Bases , Diferenciação Celular/genética , Células Cultivadas , Epigênese Genética , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Modelos Biológicos , Processamento Pós-Transcricional do RNA , RNA Longo não Codificante/química , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
13.
Nucleic Acids Res ; 43(11): 5409-22, 2015 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-25934799

RESUMO

The maturation of induced pluripotent stem cells (iPS) is one of the limiting steps of somatic cell reprogramming, but the underlying mechanism is largely unknown. Here, we reported that knockdown of histone deacetylase 2 (HDAC2) specifically promoted the maturation of iPS cells. Further studies showed that HDAC2 knockdown significantly increased histone acetylation, facilitated TET1 binding and DNA demethylation at the promoters of iPS cell maturation-related genes during the transition of pre-iPS cells to a fully reprogrammed state. We also found that HDAC2 competed with TET1 in the binding of the RbAp46 protein at the promoters of maturation genes and knockdown of TET1 markedly prevented the activation of these genes. Collectively, our data not only demonstrated a novel intrinsic mechanism that the HDAC2-TET1 switch critically regulates iPS cell maturation, but also revealed an underlying mechanism of the interplay between histone acetylation and DNA demethylation in gene regulation.


Assuntos
Reprogramação Celular , Cromatina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Histona Desacetilase 2/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Ativação Transcricional , Acetilação , Animais , Células Cultivadas , DNA/metabolismo , Histona Desacetilase 2/antagonistas & inibidores , Histona Desacetilase 2/genética , Histonas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Camundongos Transgênicos
14.
J Biol Chem ; 290(50): 30193-203, 2015 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-26487723

RESUMO

The transcription of human telomerase gene hTERT is regulated by transcription factors (TFs), including Sp1 family proteins, and its chromatin environment. To understand its regulation in a relevant chromatin context, we employed bacterial artificial chromosome reporters containing 160 kb of human genomic sequence containing the hTERT gene. Upon chromosomal integration, the bacterial artificial chromosomes recapitulated endogenous hTERT expression, contrary to transient reporters. Sp1/Sp3 expression did not correlate with hTERT promoter activity, and these TFs bound to the hTERT promoters in both telomerase-positive and telomerase-negative cells. Mutation of the proximal GC-box resulted in a dramatic decrease of hTERT promoter activity, and mutations of all five GC-boxes eliminated its transcriptional activity. Neither mutations of GC-boxes nor knockdown of endogenous Sp1 impacted promoter binding by other TFs, including E-box-binding proteins, and histone acetylation and trimethylation of histone H3K9 at the hTERT promoter in telomerase-positive and -negative cells. The result indicated that promoter binding by Sp1/Sp3 was essential, but not a limiting step, for hTERT transcription. hTERT transcription required a permissive chromatin environment. Importantly, our data also revealed different functions of GC-boxes and E-boxes in hTERT regulation; although GC-boxes were essential for promoter activity, factors bound to the E-boxes functioned to de-repress hTERT promoter.


Assuntos
Cromatina/metabolismo , Regiões Promotoras Genéticas , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição Sp3/metabolismo , Telomerase/genética , Transcrição Gênica , Linhagem Celular , Humanos , Ligação Proteica
15.
J Biol Chem ; 290(18): 11282-92, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25814666

RESUMO

Human BUB3 is a key mitotic checkpoint factor that recognizes centromeric components and recruits other mitotic checkpoint molecules to the unattached kinetochore. The key amino acid residues responsible for its localization are not yet defined. In this study, we identified a motif from Lys(216) to Lys(222) in BUB3 as its nuclear localization signal. A BUB3 mutant with deletion of this motif (Del216-222) was found to localize to both the cytoplasm and the nucleus, distinct from the exclusively nuclear distribution of wild-type BUB3. Further analysis revealed that residues Glu(213), Lys(216), Lys(217), Lys(218), Tyr(219), and Phe(221), but not Lys(222), contribute to nuclear localization. Interestingly, the nuclear localization signal was also critical for the kinetochore localization of BUB3. The deletion mutant Del216-222 and a subtle mutant with four residue changes in this region (E213Q/K216E/K217E/K218E (QE)) did not localize to the kinetochore efficiently or mediate mitotic checkpoint arrest. Protein interaction data suggested that the QE mutant was able to interact with BUB1, MAD2, and BubR1 but that its association with the centromeric components CENP-A and KNL1 was impaired. A motif from Leu(61) to Leu(65) in CENP-A was found to be involved in the association of BUB3 and CENP-A in cells; however, further assays suggested that CENP-A does not physically interact with BUB3 and does not affect BUB3 localization. Our findings help to dissect the mechanisms of BUB3 in mitotic checkpoint signaling.


Assuntos
Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Lisina , Pontos de Checagem da Fase M do Ciclo Celular , Sinais de Localização Nuclear , Transporte Ativo do Núcleo Celular , Motivos de Aminoácidos , Sequência de Aminoácidos , Autoantígenos/metabolismo , Proteínas de Ciclo Celular/genética , Proteína Centromérica A , Proteínas Cromossômicas não Histona/metabolismo , Células HEK293 , Células HeLa , Humanos , Cinetocoros/metabolismo , Dados de Sequência Molecular , Mutação , Proteínas de Ligação a Poli-ADP-Ribose , Transdução de Sinais
16.
Stem Cells ; 33(3): 661-73, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25335925

RESUMO

Leukemia inhibitory factor/Stat3 signaling is critical for maintaining the self-renewal and differentiation potential of mouse embryonic stem cells (mESCs). However, the upstream effectors of this pathway have not been clearly defined. Here, we show that periodic tryptophan protein 1 (Pwp1), a WD-40 repeat-containing protein associated with histone H4 modification, is required for the exit of mESCs from the pluripotent state into all lineages. Knockdown (KD) of Pwp1 does not affect mESC proliferation, self-renewal, or apoptosis. However, KD of Pwp1 impairs the differentiation potential of mESCs both in vitro and in vivo. PWP1 chromatin immunoprecipitation-seq results revealed that the PWP1-occupied regions were marked with significant levels of H4K20me3. Moreover, Pwp1 binds to sites in the upstream region of Stat3. KD of Pwp1 decreases the level of H4K20me3 in the upstream region of Stat3 gene and upregulates the expression of Stat3. Furthermore, Pwp1 KD mESCs recover their differentiation potential through suppressing the expression of Stat3 or inhibiting the tyrosine phosphorylation of STAT3. Together, our results suggest that Pwp1 plays important roles in the differentiation potential of mESCs.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Células-Tronco Embrionárias/metabolismo , Proteínas Nucleares/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Células-Tronco Embrionárias/citologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Células HEK293 , Humanos , Camundongos , Proteínas Nucleares/genética , Transdução de Sinais
17.
Neural Netw ; 171: 145-158, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38091759

RESUMO

A nonconvex distributed optimization problem involving nonconvex objective functions and inequality constraints within an undirected multi-agent network is considered. Each agent communicates with its neighbors while only obtaining its individual local information (i.e. its constraint and objective function information). To overcome the challenge caused by the nonconvexity of the objective function, a collective neurodynamic penalty approach in the framework of particle swarm optimization is proposed. The state solution convergence of every neurodynamic penalty approach is directed towards the critical point ensemble of the nonconvex distributed optimization problem. Furthermore, employing their individual neurodynamic models, each neural network conducts accurate local searches within constraints. Through the utilization of both locally best-known solution information and globally best-known solution information, along with the incremental enhancement of solution quality through iterations, the globally optimal solution for a nonconvex distributed optimization problem can be found. Simulations and an application are presented to demonstrate the effectiveness and feasibility.


Assuntos
Algoritmos , Redes Neurais de Computação , Simulação por Computador
18.
Heliyon ; 10(10): e30968, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38826705

RESUMO

Background: Efficiently increasing the production of clinical-grade mesenchymal stem cells (MSCs) is crucial for clinical applications. Challenges with the current planar culture methods include scalability issues, labour intensity, concerns related to cell senescence, and heterogeneous responses. This study aimed to establish a large-scale production system for MSC generation. In addition, a comparative analysis of the biological differences between MSCs cultured under various conditions was conducted. Methods and materials: We developed a GMP-grade three-dimensional hypoxic large-scale production (TDHLSP) system for MSCs using self-fabricated glass microcarriers and a multifunctional bioreactor. Different parameters, including cell viability, cell diameter, immunophenotype, morphology, karyotype, and tumourigenicity were assessed in MSCs cultured using different methods. Single-cell RNA sequencing (scRNA-seq) revealed pathways and genes associated with the enhanced functionality of MSCs cultured in three dimensions under hypoxic conditions (3D_Hypo MSCs). Moreover, CD142 knockdown in 3D_Hypo MSCs confirmed its in vitro functions. Results: Inoculating 2 × 108 MSCs into a 2.6 L bioreactor in the TDHLSP system resulted in a final scale of 4.6 × 109 3D_Hypo MSCs by day 10. The 3D_Hypo MSCs retained characteristics of the 2D MSCs, demonstrating their genomic stability and non-tumourigenicity. Interestingly, the subpopulations of 3D_Hypo MSCs exhibited a more uniform distribution and a closer relationship than those of 2D MSCs. The heterogeneity of MSCs was strongly correlated with 'cell cycle' and 'stroma/mesenchyme', with 3D_Hypo MSCs expressing higher levels of activated stroma genes. Compared to 2D MSCs, 3D_Hypo MSCs demonstrated enhanced capabilities in blood vessel formation, TGF-ß1 secretion, and inhibition of BV2 proliferation, with maintenance of Senescence-Associated ß-Galactosidase (SA-ß-gal) negativity. However, the enhanced functions of 3D_Hypo MSCs decreased upon the downregulation of CD142 expression. Conclusion: The TDHLSP system led to a high overall production of MSCs and promoted uniform distribution of MSC clusters. This cultivation method also enhanced key cellular properties, such as angiogenesis, immunosuppression, and anti-aging. These functionally improved and uniform MSC subpopulations provide a solid basis for the clinical application of stem cell therapies.

19.
Stem Cell Res Ther ; 15(1): 122, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38679727

RESUMO

BACKGROUND: Mesenchymal stem cells (MSCs) hold a great promise for cell-based therapy in the field of regenerative medicine. In this study, we aimed to evaluate the safety and efficacy of intravenous infusion of human umbilical cord-derived MSCs (HUC-MSCs) in patients with aging frailty. METHODS: In this randomized, double-blind, placebo-controlled trial, participants diagnosed with aging frailty were randomly assigned to receive intravenous administrations of HUC-MSCs or placebo. All of serious adverse events and AEs were monitored to evaluate the safety of treatment during the 6-month follow-up. The primary efficacy endpoint was alteration of physical component scores (PCS) of SF-36 qualities of life at 6 months. The secondary outcomes including physical performance tests and pro-inflammatory cytokines, were also observed and compared at each follow-up visits. All evaluations were performed at 1 week, 1, 2, 3 and 6 months following the first intravenous infusion of HUC-MSCs. RESULTS: In the MSCs group, significant improvements in PCS of SF-36 were observed from first post-treatment visit and sustained throughout the follow-up period, with greater changes compared to the placebo group (p = 0.042). EQ-VAS scores of MSCs group improved significantly at 2 month (p = 0.023) and continued until the end of the 6-month visit (p = 0.002) in comparison to the placebo group. The timed up and go (TUG) physical performance test revealed significant group difference and showed continual enhancements over 6 months (p < 0.05). MSC transplantation improved the function of 4-m walking test (4MWT) compared with the placebo group with a decrease of 2.05 s at 6 months of follow-up (p = 0.21). The measurement of grip strength revealed group difference with MSCs group demonstrating better performance, particularly at 6 months (p = 0.002). Inflammatory cytokines (TNF-α, IL-17) exhibited declines in MSCs group at 6 months compared to the placebo group (p = 0.034 and 0.033, respectively). There was no difference of incidence of AEs between the two groups. CONCLUSION: Intravenous transplantation of HUC-MSCs is a safe and effective therapeutic approach on aging frailty. The positive outcomes observed in improving quality of life, physical performance, and reducing chronic inflammation, suggest that HUC-MSC therapy may be a promising potential treatment option for aging frailty. TRIAL REGISTRATION: Clinicaltrial.gov; NCT04314011; https://clinicaltrials.gov/ct2/show/NCT04314011 .


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Qualidade de Vida , Cordão Umbilical , Humanos , Feminino , Masculino , Método Duplo-Cego , Transplante de Células-Tronco Mesenquimais/métodos , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Idoso , Células-Tronco Mesenquimais/citologia , Cordão Umbilical/citologia , Fragilidade/terapia , Pessoa de Meia-Idade , Envelhecimento/fisiologia , Idoso de 80 Anos ou mais , Resultado do Tratamento
20.
Digit Health ; 10: 20552076241257447, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38840657

RESUMO

Objective: This study aimed to compare the effectiveness of instant versus text messaging intervention (TMI) on antiretroviral therapy (ART) adherence among men who have sex with men (MSM) living with HIV. Methods: This study was conducted in an infectious disease hospital of Jinan, China from October 2020 to June 2021, using non-randomized concurrent controlled design to compare the effectiveness of instant messaging intervention (IMI) versus TMI. The intervention strategies (health messaging, medication reminder, and peer education) and contents were consistent between the two groups, and the difference was service delivery method and type of information. The primary outcome was the proportion of achieving optimal ART adherence, defined as never missing any doses and delayed any doses more than 1 hour. Results: A total of 217 participants (including 72 in TMI group and 145 in IMI group) were included in the study. The proportion of achieving optimal adherence was higher in IMI group than TMI group at the first follow-up (90.2% versus 77.6%, p = 0.021) and second follow-up (86.5% versus 76.6%, p = 0.083). The effect of IMI versus TMI on improving ART adherence was found not to be statistically significant (risk ratio (RR) = 1.93, 95% confidence interval (CI): 0.95-3.94) in complete-case analysis. However, when excluding participants who did not adhere to the interventions, a significant improvement was observed (RR = 2.77, 95%CI: 1.21-6.38). More participants in IMI group expressed highly rated satisfaction to the intervention services than those in TMI group (67.3% versus 50.0%). Conclusions: The IMI demonstrated superior efficacy over TMI in improving ART adherence and satisfaction with intervention services. It is suggested that future digital health interventions targeting ART adherence should prioritize instant messaging with multimedia information in areas with Internet access. Trial registration: The study was registered at the Chinese Clinical Trial Register (ChiCTR), with number [ChiCTR2000041282].

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