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1.
Clin Lab ; 70(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38747908

RESUMO

BACKGROUND: miR-34a has been implicated in many autoimmune diseases and gastrointestinal diseases. However, the expression of miR-34 in ulcerative colitis (UC) patients were not fully studied. This study was performed to in-vestigate the association of blood and intestinal tissue miR-34a expression of patients with disease severity in UC patients. METHODS: Our study enrolled 82 patients with UC and 80 age- and gender- matched healthy individuals. Blood miR-34a expressions were detected using reverse transcription-polymerase chain reaction (RT-PCR). Local intestinal miR-34a, STAT3 mRNA and IL-23 mRNA expressions were also detected in the lesioned area and adjacent non-affected intestinal tissue in patients. Disease severity of UC was assessed by Mayo score. The diagnostic value of both blood and local miR-34a expression for UC patients was assessed by receiver operating characteristic (ROC) curve. RESULTS: Blood miR-34a was increased in UC patients in contrast with healthy individuals with statistical significance. In UC patients, local intestinal miR-34a expressions were markedly upregulated compared to adjacent non-affected intestinal tissue. Local intestinal miR-34a expressions were positively correlated with STAT3 mRNA and IL-23 mNRA. Both blood and local miR-34a expressions were significantly and positively related to Mayo scores. ROC curve analysis indicated that both blood and local miR-34a expressions may act as decent marker for Mayo grade. CONCLUSIONS: Blood and intestinal tissue miR-34a expressions are correlated with disease severity in UC patients. Both blood and intestinal tissue miR-34a expressions may serve as potential diagnostic and prognostic makers for UC. Therapeutic methods targeting miR-34a may act as potential ways for UC treatment.


Assuntos
Colite Ulcerativa , Mucosa Intestinal , MicroRNAs , Fator de Transcrição STAT3 , Índice de Gravidade de Doença , Feminino , Humanos , Masculino , Biomarcadores/sangue , Estudos de Casos e Controles , Colite Ulcerativa/genética , Colite Ulcerativa/sangue , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/metabolismo , Interleucina-23/sangue , Interleucina-23/genética , Mucosa Intestinal/metabolismo , MicroRNAs/sangue , MicroRNAs/genética , RNA Mensageiro/genética , RNA Mensageiro/sangue , RNA Mensageiro/metabolismo , Curva ROC , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
2.
Int J Mol Sci ; 25(18)2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39337578

RESUMO

The de novo synthesis of cytidine 5'-triphosphate (CTP) is catalyzed by the enzyme CTP synthase (CTPS), which is known to form cytoophidia across all three domains of life. In this study, we use the budding yeast Saccharomyces cerevisiae and the fission yeast Schizosaccharomyces pombe as model organisms to compare cytoophidium assembly under external environmental and intracellular CTPS alterations. We observe that under low and high temperature conditions, cytoophidia in fission yeast gradually disassemble, while cytoophidia in budding yeast remain unaffected. The effect of pH changes on cytoophidia maintenance in the two yeast species is different. When cultured in the yeast-saturated cultured medium, cytoophidia in fission yeast disassemble, while cytoophidia in budding yeast gradually form. Overexpression of CTPS results in the presence and maintenance of cytoophidia in both yeast species from the log phase to the stationary phase. In summary, our results demonstrate differential cytoophidium assembly between Saccharomyces cerevisiae and Schizosaccharomyces pombe, the two most studied yeast species.


Assuntos
Carbono-Nitrogênio Ligases , Saccharomyces cerevisiae , Schizosaccharomyces , Schizosaccharomyces/metabolismo , Schizosaccharomyces/genética , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Carbono-Nitrogênio Ligases/metabolismo , Carbono-Nitrogênio Ligases/genética , Citidina Trifosfato/metabolismo , Concentração de Íons de Hidrogênio , Temperatura , Proteínas de Schizosaccharomyces pombe/metabolismo , Proteínas de Schizosaccharomyces pombe/genética
3.
Int J Mol Sci ; 25(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38203781

RESUMO

Cytidine triphosphate synthase (CTPS) forms cytoophidia in all three domains of life. Here we focus on the function of cytoophidia in cell proliferation using Schizosaccharomyces pombe as a model system. We find that converting His359 of CTPS into Ala359 leads to cytoophidium disassembly. By reducing the level of CTPS protein or specific mutation, the loss of cytoophidia prolongs the G2 phase and expands cell size. In addition, the loss-filament mutant of CTPS leads to a decrease in the expression of genes related to G2/M transition and cell growth, including histone chaperone slm9. The overexpression of slm9 alleviates the G2 phase elongation and cell size enlargement induced by CTPS loss-filament mutants. Overall, our results connect cytoophidia with cell cycle and cell size control in Schizosaccharomyces pombe.


Assuntos
Schizosaccharomyces , Schizosaccharomyces/genética , Ciclo Celular/genética , Divisão Celular , Proliferação de Células , Fase G2
4.
Int J Mol Sci ; 23(19)2022 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-36233000

RESUMO

CTP synthase (CTPS) can form filamentous structures termed cytoophidia in cells in all three domains of life. In order to study the mesoscale structure of cytoophidia, we perform fluorescence recovery after photobleaching (FRAP) and stimulated emission depletion (STED) microscopy in human cells. By using an EGFP dimeric tag as a tool to explore the physical properties of cytoophidia, we find that cytoophidia are dynamic and reticular. The reticular structure of CTPS cytoophidia may provide space for other components, such as IMPDH. In addition, we observe CTPS granules with tentacles.


Assuntos
Carbono-Nitrogênio Ligases , Citidina Trifosfato , Citidina Trifosfato/metabolismo , Humanos , Silanos
5.
Yeast ; 38(4): 276-289, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33294993

RESUMO

CTP synthase (CTPS) cytoophidia have been found in many species over domains of life in the past 10 years, implying the evolutionary conservation of these structures. However, there are differences in cytoophidia between species. The difference in CTPS cytoophidium properties between budding yeast (Saccharomyces cerevisiae) and fission yeast (Schizosaccharomyces pombe) inspires this research. We study the effects of culture environment on cytoophidia in S. cerevisiae by switching to the optimal medium for S. pombe. S. cerevisiae CTPS cytoophidium fragmentation and pseudohyphae formation are observed after treatment with S. pombe medium YES instead of S. cerevisiae medium YPD. By modifying the level of each ingredient of the media, we find that hypoosmolality impedes cytoophidium integrity during nitrogen starvation. Our study demonstrates the relationship between cytoophidium integrity and environmental stress, supporting the role of cytoophidia in stress resistance.


Assuntos
Carbono-Nitrogênio Ligases/metabolismo , Meios de Cultura/química , Nitrogênio/metabolismo , Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/metabolismo , Carbono-Nitrogênio Ligases/genética , Meios de Cultura/farmacologia , Concentração Osmolar , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Schizosaccharomyces/efeitos dos fármacos , Schizosaccharomyces/enzimologia , Schizosaccharomyces/genética , Estresse Fisiológico/efeitos dos fármacos
6.
J Adv Nurs ; 77(1): 266-274, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33074555

RESUMO

AIMS: To assess the prevalence and associated factors of psychological distress among patients with chronic hepatitis B receiving oral antiviral therapy and explore the association between psychological distress and self-management behaviours among this population. DESIGN: A cross-sectional study. METHODS: A convenience sample of 188 patients with chronic hepatitis B receiving oral antiviral therapy was recruited from March-October 2018 to complete a self-report questionnaire including the Chinese version of Depression Anxiety Stress Scale-21 and Chronic Hepatitis B Self-Management Scale. Logistic regression analysis and hierarchical multiple regression analysis were used to determine the factors associated with psychological distress and the association between psychological distress and self-management behaviours respectively. RESULTS: The prevalence of depression, anxiety, and stress symptoms were 33.0%, 38.3% and 17.6% respectively. Depression was associated with older age, female gender, lower education level and longer treatment duration; anxiety was associated with female gender and longer treatment duration; and stress was associated with age of 31-40 years, female gender and unmarried status. There were significant associations between depression and anxiety symptoms and self-management behaviours. CONCLUSION: Psychological distress was prevalent among patients with chronic hepatitis B receiving oral antiviral therapy and had a negative impact on self-management. Interventions targeting depression and anxiety symptoms may be beneficial to improve self-management behaviours for this population. IMPACT: This study explored the factors associated with psychological distress in patients with chronic hepatitis B receiving oral antiviral therapy. The findings showed psychological distress was more common in patients who were with older age, female, less educated, unmarried and receiving longer duration of treatment and psychological distress was significantly associated with self-management behaviours. Nurses and other healthcare providers should provide interventions to reduce the risk of psychological distress and improve self-management behaviours for this population.


Assuntos
Hepatite B Crônica , Angústia Psicológica , Autogestão , Adulto , Idoso , Antivirais/uso terapêutico , Ansiedade/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Feminino , Hepatite B Crônica/tratamento farmacológico , Humanos , Estresse Psicológico , Inquéritos e Questionários
7.
J Res Med Sci ; 21: 4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27904550

RESUMO

BACKGROUND: To investigate the relation between serum leptin levels and cerebral infarction (CI) by meta-analysis. MATERIALS AND METHODS: Scientific literature databases were searched for studies published in Chinese and English. After retrieving relevant articles through database searches and screening using predefined selection criteria, high-quality studies related to our research topic were selected for inclusion in this meta-analysis. All statistical analyses were conducted using Comprehensive Meta-Analysis 2.0 (CMA 2.0, Biostat Inc., Englewood, New Jersey, USA). RESULTS: The study results revealed that serum leptin levels were significantly higher in CI patients as compared to normal controls. The outcomes of subgroup analysis by ethnicity suggested that the serum leptin levels in CI patients were significantly higher than normal controls in both Asian and Caucasian populations. Further, subgroup analysis based on the detection method indicated that the serum leptin levels in CI patients were significantly higher compared with normal controls when measured by radioimmunoassay (RIA) but enzyme-linked immunosorbent assay (ELISA)-based measurements did not show such statistically significant differences. CONCLUSION: Our meta-analysis results suggest that serum leptin levels in CI patients may be closely correlated with CI risks.

8.
Cell Biosci ; 13(1): 100, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37248548

RESUMO

BACKGROUND: PRPP synthase (PRPS) transfers the pyrophosphate groups from ATP to ribose-5-phosphate to produce 5-phosphate ribose-1-pyrophosphate (PRPP), a key intermediate in the biosynthesis of several metabolites including nucleotides, dinucleotides and some amino acids. There are three PRPS isoforms encoded in human genome. While human PRPS1 (hPRPS1) and human PRPS2 (hPRPS2) are expressed in most tissues, human PRPS3 (hPRPS3) is exclusively expressed in testis. Although hPRPS1 and hPRPS2 share 95% sequence identity, hPRPS2 has been shown to be less sensitive to allosteric inhibition and specifically upregulated in certain cancers in the translational level. Recent studies demonstrate that PRPS can form a subcellular compartment termed the cytoophidium in multiple organisms across prokaryotes and eukaryotes. Forming filaments and cytoophidia is considered as a distinctive mechanism involving the polymerization of the protein. Previously we solved the filament structures of Escherichia coli PRPS (ecPRPS) using cryo-electron microscopy (cryo-EM) 1. RESULTS: Order to investigate the function and molecular mechanism of hPRPS2 polymerization, here we solve the polymer structure of hPRPS2 at 3.08 Å resolution. hPRPS2 hexamers stack into polymers in the conditions with the allosteric/competitive inhibitor ADP. The binding modes of ADP at the canonical allosteric site and at the catalytic active site are clearly determined. A point mutation disrupting the inter-hexamer interaction prevents hPRPS2 polymerization and results in significantly reduced catalytic activity. CONCLUSION: Findings suggest that the regulation of hPRPS2 polymer is distinct from ecPRPS polymer and provide new insights to the regulation of hPRPS2 with structural basis.

9.
Polymers (Basel) ; 14(8)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35458317

RESUMO

In this study, hydromagnesite, a rare natural hydrated alkaline magnesium carbonate, was used to synthesize magnesium hydroxide (MH) as a flame retardant for ethylene-vinyl acetate (EVA) to enhance its fire resistance and smoke suppression. Various concentrations of sodium hydroxide (NaOH) were used to alter the morphology and the flame-retardant efficiency of synthesized MH. EVA/MH composites were prepared through melt blending, and the influence of NaOH on the flame retardancy and mechanical properties was investigated by means of the limiting oxygen index (LOI), cone calorimeter test (CCT) and tensile test. The flame retardancy results demonstrated that composites exhibited remarkably improved flame retardant properties after introducing MH, reflected by an increase in the LOI value from 20% for neat EVA to roughly 38%. Additionally, the peak of heat release rate (pHRR), the total heat release (THR) and the peak of the smoke production rate for EVA3 were decreased by 37.6%, 20.7% and 44.4% compared with neat EVA, respectively. In the meantime, increasing char residues were also observed. The incorporation of different MH concentrations had a limited effect on the mechanical properties of the EVA/MH composites.

10.
Int J Nurs Stud ; 116: 103382, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31402047

RESUMO

BACKGROUND: Chronic hepatitis B is a serious and chronic health problem, requiring self-management to control the disease and related complications. OBJECTIVES: To develop a structural model to identify how social support, self-efficacy and disease knowledge contribute to their self-management behaviors in adults with chronic hepatitis B. DESIGN: A cross-sectional study. SETTINGS: Hepatology units in two hospitals in Chongqing, China. PARTICIPANTS: A total of 306 patients with chronic hepatitis B were recruited. METHODS: Data were collected using Social Support Rating Scale, Self-Efficacy for Managing Chronic Disease, Hepatitis B Knowledge Questionnaire and Chronic Hepatitis B Self-Management Scale. Structural equation model was applied to analyze the data. RESULTS: The final model showed good model fit. Social support directly influenced self-management behaviors (ß = 0.19, p < 0.01), and indirectly influenced self-management behaviors (ß = 0.20, p < 0.01) through self-efficacy. Self-efficacy directly influenced self-management behaviors (ß = 0.37, p < 0.05). Disease knowledge indirectly influenced self-management behaviors (ß = 0.12, p < 0.05) through self-efficacy. CONCLUSIONS: Our findings indicated that social support, self-efficacy and disease knowledge directly or indirectly affected self-management behaviors in adults with chronic hepatitis B. This provides a theoretical basis for developing self-management interventions for patients with chronic hepatitis B, which may lead to health improvements in this population.


Assuntos
Hepatite B Crônica , Autogestão , Adulto , China , Estudos Transversais , Hepatite B Crônica/terapia , Humanos , Autoeficácia , Apoio Social
11.
Emerg Microbes Infect ; 10(1): 1751-1759, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34396940

RESUMO

The effectiveness of inactivated SARS-CoV-2 vaccines against the Delta variant, which has been associated with greater transmissibility and virulence, remains unclear. We conducted a test-negative case-control study to explore the vaccine effectiveness (VE) in real-world settings. We recruited participants aged 18-59 years who consisted of SARS-CoV-2 test-positive cases (n = 74) and test-negative controls (n = 292) during the outbreak of the Delta variant in May 2021 in Guangzhou city, China. Vaccination status was compared to estimate The VE of SARS-CoV-2 inactivated vaccines. A single dose of inactivated SARS-CoV-2 vaccine yielded the VE of only 13.8%. After adjusting for age and sex, the overall VE for two-dose vaccination was 59.0% (95% confidence interval: 16.0% to 81.6%) against coronavirus disease 2019 (COVID-19) and 70.2% (95% confidence interval: 29.6-89.3%) against moderate COVID-19 and 100% against severe COVID-19 which might be overestimated due to the small sample size. The VE of two-dose vaccination against COVID-19 reached 72.5% among participants aged 40-59 years, and was higher in females than in males against COVID-19 and moderate diseases. While single dose vaccination was not sufficiently protective, the two-dose dosing scheme of the inactivated vaccines was effective against the Delta variant infection in real-world settings, with the estimated efficacy exceeding the World Health Organization minimal threshold of 50%.


Assuntos
Vacinas contra COVID-19/normas , COVID-19/prevenção & controle , SARS-CoV-2/genética , Adolescente , Adulto , Distribuição por Idade , COVID-19/classificação , Vacinas contra COVID-19/administração & dosagem , Estudos de Casos e Controles , China , Surtos de Doenças , Feminino , Variação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/normas , Adulto Jovem
12.
Int J Ophthalmol ; 12(7): 1116-1121, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31341801

RESUMO

AIM: To study the effect of an innovative micro-dissection procedure by radiofrequency ablation (MRA) in removing eyelid nevus. METHODS: Fifty-six consecutive outpatients with eyelid nevus were treated with MRA using a monopolar device. The effect of MRA was determined after following-up for 6mo to 5y. RESULTS: Fifty-two cases (52 eyes, 92.9%) were cured once, and 4 cases (4 eyes, 7.1%) received second treatment for small residual. All cases healed well after surgery, with no pigmentation, no scars, no loss of eyelashes, no deformation of eyelid margin. There was no visual impairment after healing. CONCLUSION: MRA of eyelid nevus using the XL-RFA device is highly efficient without significant complications.

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