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1.
Proc Natl Acad Sci U S A ; 120(11): e2219170120, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36888657

RESUMO

The enrichment of histone H3 variant CENP-A is the epigenetic mark of centromere and initiates the assembly of the kinetochore at centromere. The kinetochore is a multi-subunit complex that ensures accurate attachment of microtubule centromere and faithful segregation of sister chromatids during mitosis. As a subunit of kinetochore, CENP-I localization at centromere also depends on CENP-A. However, whether and how CENP-I regulates CENP-A deposition and centromere identity remains unclear. Here, we identified that CENP-I directly interacts with the centromeric DNA and preferentially recognizes AT-rich elements of DNA via a consecutive DNA-binding surface formed by conserved charged residues at the end of N-terminal HEAT repeats. The DNA binding-deficient mutants of CENP-I retained the interaction with CENP-H/K and CENP-M, but significantly diminished the centromeric localization of CENP-I and chromosome alignment in mitosis. Moreover, the DNA binding of CENP-I is required for the centromeric loading of newly synthesized CENP-A. CENP-I stabilizes CENP-A nucleosomes upon binding to nucleosomal DNA instead of histones. These findings unveiled the molecular mechanism of how CENP-I promotes and stabilizes CENP-A deposition and would be insightful for understanding the dynamic interplay of centromere and kinetochore during cell cycle.


Assuntos
Centrômero , Proteínas Cromossômicas não Histona , Proteína Centromérica A/genética , Proteína Centromérica A/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Centrômero/genética , Centrômero/metabolismo , Histonas/genética , Histonas/metabolismo , Nucleossomos/genética , DNA/genética , Mitose , Autoantígenos/metabolismo
2.
Artigo em Inglês | MEDLINE | ID: mdl-38551445

RESUMO

Objective: To explore the effect of humanistic pain management based on active pain assessment and the visual analog scale in postpartum women after cesarean delivery. Methods: We selected 100 postpartum women who underwent cesarean delivery in Xuzhou Maternity and Child Health Care Hospital from April to December 2021 and divided the postpartum women into a management group and a conventional group, with 50 cases in each group. The conventional group was given routine pain management, while the management group was given humanistic pain management based on active pain assessment and visual analog scale score. The quality of pain management, sleep quality, unhealthy emotion, maternal comfort, breastfeeding rates, and patient compliance in the 2 groups were compared. Results: The most severe degree of pain, the least degree of pain, the frequency of moderate and severe pain, and the influence of pain on sleep were lower in the management group than in the conventional group. The Pittsburgh Sleep Quality Index score was lower and the Self-Rating Anxiety Scale and the Self-Rating Depression Scale scores were higher in the management group than in the conventional group. In addition, the comfort scores for the second day and the third day after delivery were higher in the management group than in the conventional group. The breastfeeding rate and patient compliance were higher in the management group than in the conventional group. Conclusion: Humanistic pain management based on active pain assessment and the visual analog scale can improve the quality of maternal pain management, the quality of sleep, and maternal comfort, ameliorate maternal adverse emotions, and promote breastfeeding and patient compliance.

3.
BMC Public Health ; 19(1): 780, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31474224

RESUMO

BACKGROUND: With the changes in environmental, medical technique, population structure and national health projects, human mortality rates have undergone great changes all over the world. According to "World Health Statistics 2016: Monitoring Health for the SDGs (Sustainable Development Goals)", we can draw a globally vision about life expectancy and cause of death; also, significant inequality still persists within and among countries. This study was designed to research into the trend of mortality pattern in China, evaluate the disparities of age-specific and disease-specific mortality rates between male and female, and provides a scientific basis for further prevention strategies and policies design. METHODS: Data from the Chinese Disease Surveillance Points system were used to calculate crude and age-adjusted death rates, annual percent changes (APC) for men and women during 2004 to 2016. Age-standardized mortality rates (ASMR) were performed through the direct method with the World Health Organization's World Standard Population. APC, according to log linear model, was adopted to describe the mortality rate trend. The χ2 test was used to compare differences between age-specific and cause-specific mortality rates of men and women. Data analysis and figures were completed by R software. RESULTS: The mortality rates of men and women have decreased significantly (P < 0.05) during 2004-2016, and the APC were1.98 and 2.45%, respectively. In 2016, the crude mortality rate (CMR) and ASMR in all causes of death were 658.50 and 490.28 per 100,000 per year, respectively. The 5 leading causes of death were malignant neoplasm, cerebrovascular disease, heart disease, COPD, and accidental injury. The mortality rates of men were higher than that of women in all age groups. CONCLUSIONS: There are severe health gaps and disparities between male and female, and the chronic non-communicable diseases continue to be a serious health threat to Chinese residents.


Assuntos
Disparidades nos Níveis de Saúde , Mortalidade/tendências , Adolescente , Adulto , Distribuição por Idade , Idoso , Causas de Morte/tendências , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Distribuição por Sexo , Adulto Jovem
4.
Zhongguo Yi Liao Qi Xie Za Zhi ; 43(6): 418-421, 2019 Nov 30.
Artigo em Zh | MEDLINE | ID: mdl-31854526

RESUMO

This paper designs and implements a low power portable bowel sound monitor, which adopts bone conduction transducer to collect bowel sound continuously for long time and transmit to phone by Bluetooth. Then the phone application can record, play and analyse the bowel sound digital data in real time. This paper also designs an experiment to collect bowel sound from healthy people and patients with intestinal obstruction. It is verified by clinicians that this monitor can accurately record and preserve the bowel sound of the detected people, and is not disturbed by the external environment.


Assuntos
Monitorização Fisiológica , Humanos , Obstrução Intestinal
5.
EMBO J ; 33(13): 1454-73, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24825347

RESUMO

Much of the mechanism by which Wnt signaling drives proliferation during oncogenesis is attributed to its regulation of the cell cycle. Here, we show how Wnt/ß-catenin signaling directs another hallmark of tumorigenesis, namely Warburg metabolism. Using biochemical assays and fluorescence lifetime imaging microscopy (FLIM) to probe metabolism in vitro and in living tumors, we observe that interference with Wnt signaling in colon cancer cells reduces glycolytic metabolism and results in small, poorly perfused tumors. We identify pyruvate dehydrogenase kinase 1 (PDK1) as an important direct target within a larger gene program for metabolism. PDK1 inhibits pyruvate flux to mitochondrial respiration and a rescue of its expression in Wnt-inhibited cancer cells rescues glycolysis as well as vessel growth in the tumor microenvironment. Thus, we identify an important mechanism by which Wnt-driven Warburg metabolism directs the use of glucose for cancer cell proliferation and links it to vessel delivery of oxygen and nutrients.


Assuntos
Neoplasias do Colo/metabolismo , Glucose/metabolismo , Glicólise , Neovascularização Patológica/metabolismo , Microambiente Tumoral , Via de Sinalização Wnt , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Glucose/genética , Humanos , Camundongos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Consumo de Oxigênio/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil
6.
Mol Syst Biol ; 13(2): 912, 2017 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-28183841

RESUMO

Cell-intrinsic metabolic reprogramming is a hallmark of cancer that provides anabolic support to cell proliferation. How reprogramming influences tumor heterogeneity or drug sensitivities is not well understood. Here, we report a self-organizing spatial pattern of glycolysis in xenograft colon tumors where pyruvate dehydrogenase kinase (PDK1), a negative regulator of oxidative phosphorylation, is highly active in clusters of cells arranged in a spotted array. To understand this pattern, we developed a reaction-diffusion model that incorporates Wnt signaling, a pathway known to upregulate PDK1 and Warburg metabolism. Partial interference with Wnt alters the size and intensity of the spotted pattern in tumors and in the model. The model predicts that Wnt inhibition should trigger an increase in proteins that enhance the range of Wnt ligand diffusion. Not only was this prediction validated in xenograft tumors but similar patterns also emerge in radiochemotherapy-treated colorectal cancer. The model also predicts that inhibitors that target glycolysis or Wnt signaling in combination should synergize and be more effective than each treatment individually. We validated this prediction in 3D colon tumor spheroids.


Assuntos
Neoplasias do Colo/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Regulação para Cima , Via de Sinalização Wnt , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Glicólise , Humanos , Camundongos , Modelos Teóricos , Transplante de Neoplasias , Piruvato Desidrogenase Quinase de Transferência de Acetil
7.
Mol Cell ; 39(1): 133-44, 2010 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-20603081

RESUMO

MicroRNAs (miRNAs) are a class of noncoding RNAs that regulate target gene expression at the posttranscriptional level. Here, we report that secreted miRNAs can serve as signaling molecules mediating intercellular communication. In human blood cells and cultured THP-1 cells, miR-150 was selectively packaged into microvesicles (MVs) and actively secreted. THP-1-derived MVs can enter and deliver miR-150 into human HMEC-1 cells, and elevated exogenous miR-150 effectively reduced c-Myb expression and enhanced cell migration in HMEC-1 cells. In vivo studies confirmed that intravenous injection of THP-1 MVs significantly increased the level of miR-150 in mouse blood vessels. MVs isolated from the plasma of patients with atherosclerosis contained higher levels of miR-150, and they more effectively promoted HMEC-1 cell migration than MVs from healthy donors. These results demonstrate that cells can secrete miRNAs and deliver them into recipient cells where the exogenous miRNAs can regulate target gene expression and recipient cell function.


Assuntos
Movimento Celular , Células Endoteliais/citologia , MicroRNAs/metabolismo , Monócitos/metabolismo , Animais , Aterosclerose/sangue , Aterosclerose/patologia , Células Sanguíneas/citologia , Células Sanguíneas/efeitos dos fármacos , Células Sanguíneas/metabolismo , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/sangue , MicroRNAs/farmacologia , Monócitos/citologia , Monócitos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myb/metabolismo , Vesículas Secretórias/efeitos dos fármacos , Vesículas Secretórias/metabolismo , Vesículas Secretórias/ultraestrutura
8.
Biochem Biophys Res Commun ; 493(1): 814-820, 2017 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-28842256

RESUMO

Genomic DNA of eukaryotic cells is hierarchically packaged into chromatin by histones. The dynamic organization of chromatin fibers plays a critical role in the regulation of gene transcription and other DNA-associated biological processes. Recently, numerous approaches have been developed to map the chromatin organization by characterizing chromatin accessibilities in genome-wide. However, reliable methods to quantitatively map chromatin accessibility are not well-established, especially not on a genome-wide scale. Here, we developed a modified MNase-seq for mouse embryonic fibroblasts, wherein chromatin was partially digested at multiple digestion times using micrococcal nuclease (MNase), allowing quantitative analysis of local yet genome-wide chromatin compaction. Our results provide strong evidence that the chromatin accessibility at promoter regions are positively correlated with gene activity. In conclusion, our assay is an ideal tool for the quantitative study of gene regulation in the perspective of chromatin accessibility.


Assuntos
Montagem e Desmontagem da Cromatina/genética , Cromatina/genética , Mapeamento Cromossômico/métodos , Segregação de Cromossomos/genética , Fibroblastos/fisiologia , Regiões Promotoras Genéticas/genética , Animais , Sítios de Ligação , Células Cultivadas , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Camundongos , Análise de Sequência de DNA/métodos
9.
J Cell Sci ; 127(Pt 9): 2017-28, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24554431

RESUMO

The Snail family of zinc-finger transcription factors are evolutionarily conserved proteins that control processes requiring cell movement. Specifically, they regulate epithelial-to-mesenchymal transitions (EMT) where an epithelial cell severs intercellular junctions, degrades basement membrane and becomes a migratory, mesenchymal-like cell. Interestingly, Slug expression has been observed in angiogenic endothelial cells (EC) in vivo, suggesting that angiogenic sprouting may share common attributes with EMT. Here, we demonstrate that sprouting EC in vitro express both Slug and Snail, and that siRNA-mediated knockdown of either inhibits sprouting and migration in multiple in vitro angiogenesis assays. We find that expression of MT1-MMP, but not of VE-Cadherin, is regulated by Slug and that loss of sprouting as a consequence of reduced Slug expression can be reversed by lentiviral-mediated re-expression of MT1-MMP. Activity of MMP2 and MMP9 are also affected by Slug expression, likely through MT1-MMP. Importantly, we find enhanced expression of Slug in EC in human colorectal cancer samples compared with normal colon tissue, suggesting a role for Slug in pathological angiogenesis. In summary, these data implicate Slug as an important regulator of sprouting angiogenesis, particularly in pathological settings.


Assuntos
Fatores de Transcrição/metabolismo , Células Cultivadas , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/fisiologia , Imunofluorescência , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Imuno-Histoquímica , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 14 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Metilcelulose/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Transcrição da Família Snail
10.
Front Public Health ; 11: 1106299, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37361146

RESUMO

Background: This study aimed to examine the associations between workload and satisfaction with working conditions and mental health (i.e., anxiety disorder, depression, and somatization) of healthcare workers collecting test samples during the local outbreaks of COVID-19, and explore satisfaction with working conditions as a moderator of these relationships. Methods: A total of 1,349 participants were obtained via an online survey in Zhengzhou, Henan Province, China. Multivariate regression was used to assess the associations between workload and satisfaction with working conditions and anxiety disorder, depression, and somatization. The simple slope analysis and Johnson-Neyman technique were used to assess the effect value and change trend of the moderator. Results: The prevalence of anxiety disorder, depression, and somatization were 8.6, 6.9, and 19.2% of healthcare workers collecting test samples, respectively. High levels of workload were associated with an increased risk of an anxiety disorder (OR = 1.81, 95%CI = 1.17-2.78), depression (OR = 1.92, 95%CI = 1.19-3.10), and somatization (OR = 1.90, 95%CI = 1.40-2.57), while high satisfaction of working conditions was associated with a reduction in the risk of these outcomes, and ORs (95%CI) were 0.35 (0.20-0.64), 0.27 (0.13-0.56), and 0.32 (0.21-0.48), respectively. The findings also indicated that a weaker association between workload and anxiety disorder, as well as depression and somatization, has been reported in those with a high level of satisfaction with working conditions. Conclusion: Workload significantly increased the risk of healthcare workers suffering from psychological problems, while satisfaction with working conditions alleviated these negative effects, and effective resource support was crucial for healthcare workers.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Saúde Mental , Carga de Trabalho , Condições de Trabalho , Depressão/epidemiologia , Pessoal de Saúde , Satisfação Pessoal
11.
Sci Adv ; 9(15): eadf4490, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-37058568

RESUMO

Liver steatosis is an increasing health issue with few therapeutic options, partly because of a paucity of experimental models. In humanized liver rodent models, abnormal lipid accumulation in transplanted human hepatocytes occurs spontaneously. Here, we demonstrate that this abnormality is associated with compromised interleukin-6 (IL-6)-glycoprotein 130 (GP130) signaling in human hepatocytes because of incompatibility between host rodent IL-6 and human IL-6 receptor (IL-6R) on donor hepatocytes. Restoration of hepatic IL-6-GP130 signaling, through ectopic expression of rodent IL-6R, constitutive activation of GP130 in human hepatocytes, or humanization of an Il6 allele in recipient mice, substantially reduced hepatosteatosis. Notably, providing human Kupffer cells via hematopoietic stem cell engraftment in humanized liver mice also corrected the abnormality. Our observations suggest an important role of IL-6-GP130 pathway in regulating lipid accumulation in hepatocytes and not only provide a method to improve humanized liver models but also suggest therapeutic potential for manipulating GP130 signaling in human liver steatosis.


Assuntos
Fígado Gorduroso , Interleucina-6 , Humanos , Camundongos , Animais , Interleucina-6/metabolismo , Receptor gp130 de Citocina/metabolismo , Gotículas Lipídicas/metabolismo , Hepatócitos/metabolismo , Glicoproteínas , Lipídeos
12.
J Biol Chem ; 286(11): 9468-76, 2011 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-21199864

RESUMO

microRNAs (miRNAs) are generally thought to negatively regulate the expression of their target genes by mRNA degradation or by translation repression. Here we show an efficient way to identify miRNA target genes by screening alterations in global mRNA levels following changes in miRNA levels. In this study, we used mRNA microarrays to measure global mRNA expression in three cell lines with increased or decreased levels of miR-16 and performed bioinformatics analysis based on multiple target prediction algorithms. For further investigation among the predicted miR-16 target genes, we selected genes that show an expression pattern opposite to that of miR-16. One of the candidate target genes that may interact with miR-16, ADP-ribosylation factor-like protein 2 (ARL2), was further investigated. First, ARL2 was deduced to be an ideal miR-16 target by computational predictions. Second, ARL2 mRNA and protein levels were significantly abolished by treatment with miR-16 precursors, whereas a miR-16 inhibitor increased ARL2 mRNA and protein levels. Third, a luciferase reporter assay confirmed that miR-16 directly recognizes the 3'-untranslated region (3'-UTR) of ARL2. Finally, we showed that miR-16 could regulate proliferation and induce a significant G0/G1 cell cycle arrest, which was due at least in part, to the down-regulation of ARL2. In summary, the present study suggests that integrating global mRNA profiling and bioinformatics tools may provide the basis for further investigation of the potential targets of a given miRNA. These results also illustrate a novel function of miR-16 targeting ARL2 in modulating proliferation and cell cycle progression.


Assuntos
Regiões 3' não Traduzidas/fisiologia , Ciclo Celular/fisiologia , Proteínas de Ligação ao GTP/biossíntese , Regulação Enzimológica da Expressão Gênica/fisiologia , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Biologia Computacional , Proteínas de Ligação ao GTP/genética , Perfilação da Expressão Gênica , Humanos , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos
13.
J Multivar Anal ; 1902022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35370319

RESUMO

In this paper, we study statistical inference in functional quantile regression for scalar response and a functional covariate. Specifically, we consider a functional linear quantile regression model where the effect of the covariate on the quantile of the response is modeled through the inner product between the functional covariate and an unknown smooth regression parameter function that varies with the level of quantile. The objective is to test that the regression parameter is constant across several quantile levels of interest. The parameter function is estimated by combining ideas from functional principal component analysis and quantile regression. An adjusted Wald testing procedure is proposed for this hypothesis of interest, and its chi-square asymptotic null distribution is derived. The testing procedure is investigated numerically in simulations involving sparse and noisy functional covariates and in a capital bike share data application. The proposed approach is easy to implement and the R code is published online at https://github.com/xylimeng/fQR-testing.

14.
Sci China Life Sci ; 65(9): 1881-1889, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35391626

RESUMO

Centromere identity is defined by nucleosomes containing CENP-A, a histone H3 variant. The deposition of CENP-A at centromeres is tightly regulated in a cell-cycle-dependent manner. We previously reported that the spatiotemporal control of centromeric CENP-A incorporation is mediated by the phosphorylation of CENP-A Ser68. However, a recent report argued that Ser68 phosphoregulation is dispensable for accurate CENP-A loading. Here, we report that the substitution of Ser68 of endogenous CENP-A with either Gln68 or Glu68 severely impairs CENP-A deposition and cell viability. We also find that mice harboring the corresponding mutations are lethal. Together, these results indicate that the dynamic phosphorylation of Ser68 ensures cell-cycle-dependent CENP-A deposition and cell viability.


Assuntos
Centrômero , Nucleossomos , Animais , Autoantígenos/metabolismo , Ciclo Celular , Centrômero/genética , Centrômero/metabolismo , Proteína Centromérica A/genética , Proteína Centromérica A/metabolismo , Histonas/genética , Histonas/metabolismo , Camundongos
15.
Stem Cell Res Ther ; 13(1): 435, 2022 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-36056394

RESUMO

BACKGROUND: Skin ageing caused by long-term ultraviolet (UV) irradiation is a complex biological process that involves multiple signalling pathways. Stem cell-conditioned media is believed to have anti-ageing effects on the skin. The purpose of this study was to explore the biological effects of UVB irradiation and anti-photoaging effects of human umbilical cord mesenchymal stem cell-conditioned medium (hUC-MSC-CM) on HaCaT cells using multi-omics analysis with a novel cellular photoaging model. METHODS: A cellular model of photoaging was constructed by irradiating serum-starved HaCaT cells with 20 mJ/cm2 UVB. Transcriptomics and proteomics analyses were used to explore the biological effects of UVB irradiation on photoaged HaCaT cells. Changes in cell proliferation, apoptosis, and migration, the cell cycle, and expression of senescence genes and proteins were measured to assess the protective effects of hUC-MSC-CM in the cellular photoaging model. RESULTS: The results of the multi-omics analysis revealed that UVB irradiation affected various biological functions of cells, including cell proliferation and the cell cycle, and induced a senescence-associated secretory phenotype. hUC-MSC-CM treatment reduced cell apoptosis, inhibited G1 phase arrest in the cell cycle, reduced the production of reactive oxygen species, and promoted cell motility. The qRT-PCR results indicated that MYC, IL-8, FGF-1, and EREG were key genes involved in the anti-photoaging effects of hUC-MSC-CM. The western blotting results demonstrated that C-FOS, C-JUN, TGFß, p53, FGF-1, and cyclin A2 were key proteins involved in the anti-photoaging effects of hUC-MSC-CM. CONCLUSION: Serum-starved HaCaT cells irradiated with 20 mJ/cm2 UVB were used to generate an innovative cellular photoaging model, and hUC-MSC-CM demonstrates potential as an anti-photoaging treatment for skin.


Assuntos
Células-Tronco Mesenquimais , Envelhecimento da Pele , Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , Fator 1 de Crescimento de Fibroblastos/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismo , Cordão Umbilical
16.
Sci Rep ; 12(1): 14079, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35982097

RESUMO

Humanized liver rodent models, in which the host liver parenchyma is repopulated by human hepatocytes, have been increasingly used for drug development and disease research. Unlike the leading humanized liver mouse model in which Fumarylacetoacetate Hydrolase (Fah), Recombination Activating Gene (Rag)-2 and Interleukin-2 Receptor Gamma (Il2rg) genes were inactivated simultaneously, generation of similar recipient rats has been challenging. Here, using Velocigene and 1-cell-embryo-targeting technologies, we generated a rat model deficient in Fah, Rag1/2 and Il2rg genes, similar to humanized liver mice. These rats were efficiently engrafted with Fah-expressing hepatocytes from rat, mouse and human. Humanized liver rats expressed human albumin and complement proteins in serum and showed a normal liver zonation pattern. Further, approaches were developed for gene delivery through viral transduction of human hepatocytes either in vivo, or in vitro prior to engraftment, providing a novel platform to study liver disease and hepatocyte-targeted therapies.


Assuntos
Hepatócitos , Hepatopatias , Animais , Modelos Animais de Doenças , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Hepatopatias/metabolismo , Camundongos , Ratos
17.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 42(3): 405-8, 2011 May.
Artigo em Zh | MEDLINE | ID: mdl-21827009

RESUMO

OBJECTIVE: To investigate the demographic characteristics of HIV-positive women of fertility age in Henan province and their knowledge and behavior in relation to AIDS. METHODS: A questionnaire survey was administered to 686 HIV-positive women of fertility age through face to face interview. The demographic characteristics of the respondents and their association with AIDS-related knowledge and behavior were analysed. RESULTS: Over 90% of respondents had good knowledge about AIDS. Statistically significant differences existed in the knowledge of AIDS and the use of condom among those with different age, education and income (P < 0.05). Age (OR < 1) and annual income (OR > 1) were identified as risk factors of failing to use condoms in regression analysis. CONCLUSION: Interventions need to be strengthened for HIV-positive women of fertility age, in particular for those who are young and have high incomes.


Assuntos
Síndrome da Imunodeficiência Adquirida , Preservativos , Soropositividade para HIV , Conhecimentos, Atitudes e Prática em Saúde , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Adolescente , Adulto , China , Feminino , Humanos , Inquéritos e Questionários , Adulto Jovem
18.
Cell Rep ; 37(6): 109987, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34758320

RESUMO

CENP-A (centromeric protein A), a histone H3 variant, specifies centromere identity and is essential to centromere maintenance. Little is known about how protein levels of CENP-A are controlled in mammalian cells. Here, we report that the phosphorylation of CENP-A Ser68 primes the ubiquitin-proteasome-mediated proteolysis of CENP-A during mitotic phase in human cultured cells. We identify two major polyubiquitination sites that are responsible for this phosphorylation-dependent degradation. Substituting the two residues, Lys49 and Lys124, with arginines abrogates proper CENP-A degradation and results in CENP-A mislocalization to non-centromeric regions. Furthermore, we find that DCAF11 (DDB1 and CUL4 associated factor 11/WDR23) is the E3 ligase that specifically mediates the observed polyubiquitination. Deletion of DCAF11 hampers CENP-A degradation and causes its mislocalization. We conclude that the Ser68 phosphorylation plays an important role in regulating cellular CENP-A homeostasis via DCAF11-mediated degradation to prevent ectopic localization of CENP-A during the cell cycle.


Assuntos
Ciclo Celular , Proteína Centromérica A/metabolismo , Proteínas Culina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Serina/metabolismo , Complexos Ubiquitina-Proteína Ligase/metabolismo , Ubiquitinação , Animais , Centrômero , Proteína Centromérica A/química , Proteína Centromérica A/genética , Cromatina/genética , Cromatina/metabolismo , Proteínas Culina/genética , Proteínas de Ligação a DNA/genética , Feminino , Histonas/genética , Histonas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nucleossomos , Fosforilação , Proteólise , Serina/química , Serina/genética , Ubiquitina/metabolismo , Complexos Ubiquitina-Proteína Ligase/genética
19.
Cell Rep ; 32(4): 107953, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32726618

RESUMO

Chromatin dynamics play a critical role in cell fate determination and maintenance by regulating the expression of genes essential for development and differentiation. In mouse embryonic stem cells (mESCs), maintenance of pluripotency coincides with a poised chromatin state containing active and repressive histone modifications. However, the structural features of poised chromatin are largely uncharacterized. By adopting mild time-course MNase-seq with computational analysis, the low-compact chromatin in mESCs is featured in two groups: one in more open regions, corresponding to an active state, and the other enriched with bivalent histone modifications, considered the poised state. A parameter called the chromatin opening potential index (COPI) is also devised to quantify the transcription potential based on the dynamic changes of MNase-seq signals at promoter regions. Use of COPI provides effective prediction of gene activation potential and, more importantly, reveals a few developmental factors essential for mouse neural progenitor cell (NPC) differentiation.


Assuntos
Cromatina/genética , Regulação da Expressão Gênica/genética , Células-Tronco Neurais/metabolismo , Animais , Diferenciação Celular/genética , Linhagem Celular , Linhagem da Célula/genética , Epigênese Genética/genética , Expressão Gênica/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Código das Histonas/genética , Histonas/metabolismo , Camundongos , Células-Tronco Embrionárias Murinas/metabolismo , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica/genética
20.
Oncotarget ; 10(40): 4004-4017, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31258845

RESUMO

Ethylmalonic Encephalopathy Protein 1 (ETHE1) is a sulfur dioxygenase that regulates cellular H2S levels. We previously demonstrated a significant increase of ETHE1 expression in "single-hit" colon epithelial cells from crypts of patients with Familial Adenomatous Polyposis (FAP). Here, we report elevated levels of ETHE1 expression and increased mitochondrial density occurring in-situ in phenotypically normal FAP colorectal mucosa. We also found that constitutive expression of ETHE1 increased aerobic glycolysis ("Warburg effect"), oxidative phosphorylation, and mitochondrial biogenesis in colorectal cancer (CRC) cell lines, thereby depleting H2S which relieved the inhibition of phosphodiesterase (PDE), and increased adenosine monophosphate (AMP) levels. This led to activation of the energy sensing AMP-activated protein kinase (AMPKp), Sirtuin1 (SIRT1) and peroxisome proliferator-activated receptor γ coactivator 1α (PGC1α), a master regulator of mitochondrial biogenesis. By contrast, shRNA silencing of ETHE1 reduced PDE activity, AMPKp/SIRT1/PGC1α levels and mitochondrial biogenesis. Constitutive expression of ETHE1 accelerated both CRC cell xenograft and orthotopic patient derived xenograft CRC cell growth in vivo. Overall, our data nominate elevated ETHE1 expression levels as a novel biomarker and potential therapeutic target for the prevention of CRC tumorigenesis.

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