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1.
Mol Ther ; 32(5): 1479-1496, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429926

RESUMO

Intense inflammatory response impairs bone marrow mesenchymal stem cell (BMSC)-mediated bone regeneration, with transforming growth factor (TGF)-ß1 being the most highly expressed cytokine. However, how to find effective and safe means to improve bone formation impaired by excessive TGF-ß1 remains unclear. In this study, we found that the expression of orphan nuclear receptor Nr4a1, an endogenous repressor of TGF-ß1, was suppressed directly by TGF-ß1-induced Smad3 and indirectly by Hdac4, respectively. Importantly, Nr4a1 overexpression promoted BMSC osteogenesis and reversed TGF-ß1-mediated osteogenic inhibition and pro-fibrotic effects. Transcriptomic and histologic analyses confirmed that upregulation of Nr4a1 increased the transcription of Wnt family member 4 (Wnt4) and activated Wnt pathway. Mechanistically, Nr4a1 bound to the promoter of Wnt4 and regulated its expression, thereby enhancing the osteogenic capacity of BMSCs. Moreover, treatment with Nr4a1 gene therapy or Nr4a1 agonist Csn-B could promote ectopic bone formation, defect repair, and fracture healing. Finally, we demonstrated the correlation of NR4A1 with osteogenesis and the activation of the WNT4/ß-catenin pathway in human BMSCs and fracture samples. Taken together, these findings uncover the critical role of Nr4a1 in bone formation and alleviation of inflammation-induced bone regeneration disorders, and suggest that Nr4a1 has the potential to be a therapeutic target for accelerating bone healing.


Assuntos
Regeneração Óssea , Inflamação , Células-Tronco Mesenquimais , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Osteogênese , Proteína Wnt4 , Células-Tronco Mesenquimais/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Osteogênese/genética , Regeneração Óssea/genética , Animais , Camundongos , Proteína Wnt4/metabolismo , Proteína Wnt4/genética , Humanos , Inflamação/genética , Inflamação/metabolismo , Regulação da Expressão Gênica , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/genética , Via de Sinalização Wnt , Masculino , Transcrição Gênica , Histona Desacetilases/metabolismo , Histona Desacetilases/genética , Modelos Animais de Doenças
2.
Stem Cells ; 41(9): 862-876, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37317792

RESUMO

Numerous intrinsic factors regulate mesenchymal progenitor commitment to a specific cell fate, such as osteogenic or adipogenic lineages. Identification and modulation of novel intrinsic regulatory factors represent an opportunity to harness the regenerative potential of mesenchymal progenitors. In the present study, the transcription factor (TF) ZIC1 was identified to be differentially expressed among adipose compared with skeletal-derived mesenchymal progenitor cells. We observed that ZIC1 overexpression in human mesenchymal progenitors promotes osteogenesis and prevents adipogenesis. ZIC1 knockdown demonstrated the converse effects on cell differentiation. ZIC1 misexpression was associated with altered Hedgehog signaling, and the Hedgehog antagonist cyclopamine reversed the osteo/adipogenic differentiation alterations associated with ZIC1 overexpression. Finally, human mesenchymal progenitor cells with or without ZIC1 overexpression were implanted in an ossicle assay in NOD-SCID gamma mice. ZIC1 overexpression led to significantly increased ossicle formation in comparison to the control, as assessed by radiographic and histologic measures. Together, these data suggest that ZIC1 represents a TF at the center of osteo/adipogenic cell fate determinations-findings that have relevance in the fields of stem cell biology and therapeutic regenerative medicine.


Assuntos
Adipogenia , Células-Tronco Mesenquimais , Animais , Camundongos , Humanos , Adipogenia/genética , Proteínas Hedgehog , Osteogênese/fisiologia , Camundongos Endogâmicos NOD , Camundongos SCID , Diferenciação Celular , Fatores de Transcrição/genética
3.
BMC Cancer ; 24(1): 116, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38262966

RESUMO

BACKGROUND: Pancreatic adenocarcinoma (PDAC) ranks as the fourth leading cause for cancer-related deaths worldwide. N6-methyladenosine (m6A) and long non-coding RNAs (lncRNAs) are closely related with poor prognosis and immunotherapeutic effect in PDAC. The aim of this study is to construct and validate a m6A-related lncRNAs signature and assess immunotherapeutic drug sensitivity in PDAC. METHODS: RNA-seq data for 178 cases of PDAC patients and 167 cases of normal pancreatic tissue were obtained from TCGA and GTEx databases, respectively. A set of 21 m6A-related genes were downloaded based on the previous report. Co-expression network was conducted to identify m6A-related lncRNAs in PDAC. Cox analyses and least absolute shrinkage and selection operator (Lasso) regression model were used to construct a risk prognosis model. The relationship between signature genes and immune function was explored by single-sample GSEA (ssGSEA). The tumor immune dysfunction and exclusion (TIDE) score and tumor mutation burden (TMB) were utilized to evaluate the response to immunotherapy. Furthermore, the expression levels of 4 m6A-related lncRNAs on PDAC cell lines were measured by the quantitative real-time PCR (qPCR). The drug sensitivity between the high- and low-risk groups was validated using PDAC cell lines by Cell-Counting Kit 8 (CCK8). RESULTS: The risk prognosis model was successfully constructed based on 4 m6A-related lncRNAs, and PDAC patients were divided into the high- and low-risk groups. The overall survival (OS) of the high-risk groups was more unfavorable compared with the low-risk groups. Receiver operating characteristic (ROC) curves demonstrated that the risk prognosis model reasonably predicted the 2-, 3- and 5-year OS of PDAC patients. qPCR analysis confirmed the decreased expression levels of 4 m6A-related lncRNAs in PDAC cells compared to the normal pancreatic cells. Furthermore, CCK8 assay revealed that Phenformin exhibited higher sensitivity in the high-risk groups, while Pyrimethamine exhibited higher sensitivity in the low-risk groups. CONCLUSION: The prognosis of patients with PDAC were well predicted in the risk prognosis model based on m6A-related lncRNAs, and selected immunotherapy drugs have potential values for the treatment of pancreatic cancer.


Assuntos
Adenina/análogos & derivados , Adenocarcinoma , Neoplasias Pancreáticas , RNA Longo não Codificante , Humanos , Pâncreas
4.
Analyst ; 149(10): 2925-2931, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38587246

RESUMO

Sensitive detection of microRNA (miRNA), one of the most promising biomarkers, plays crucial roles in cancer diagnosis. However, the low expression level of miRNA makes it extremely urgent to develop ultrasensitive and highly selective strategies for quantification of miRNA. Herein, a DNA machine is rationally constructed for amplified detection and imaging of low-abundance miRNA in living cells based on the toehold-mediated strand displacement reaction (TMSDR). The isothermal and enzyme-free DNA machine with low background leakage is fabricated by integrating two DNA circuits into a cascade system, in which the output of one circuit serves as the input of the other one. Once the DNA machine is transfected into breast cancer cells, the overexpressed miRNA-203 initiates the first-layer circuit through TMSDR, leading to the concentration variation of fuel strands, which further influences the assembly of hairpin DNA in the second-layer circuit and the occurrence of fluorescence resonance energy transfer (FRET) for fluorescence imaging. Benefiting from the cascade of the two-layer amplification reaction, the proposed DNA machine acquires a detection limit down to 4 fM for quantification of miR-203 and a 10 000-fold improvement in amplification efficiency over the single circuit. Therefore, the two-layer circuit cascade-based DNA machine provides an effective platform for amplified analysis of low-abundance miRNA with high sensitivity, which holds great promise in biomedical and clinical research.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Limite de Detecção , MicroRNAs , MicroRNAs/análise , Humanos , Transferência Ressonante de Energia de Fluorescência/métodos , Técnicas Biossensoriais/métodos , DNA/química , Técnicas de Amplificação de Ácido Nucleico/métodos , Células MCF-7 , Imagem Óptica/métodos , Linhagem Celular Tumoral , Hibridização de Ácido Nucleico
5.
Lipids Health Dis ; 23(1): 42, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38331880

RESUMO

BACKGROUND: Lewy body dementia (LBD) ranks second among prevalent neurodegenerative dementias. Previous studies have revealed associations of serum lipid measures with several neurodegenerative diseases. Nevertheless, the potential connection between serum lipids and LBD remains undetermined. In this study, Mendelian randomization (MR) analyses were carried out to assess the causal relationships of several serum lipid measures with the risk of developing LBD. METHODS: Genome-wide association study (GWAS) data for serum lipids and LBD in European descent individuals were acquired from publicly available genetic summary data. A series of filtering procedures were conducted to identify the genetic variant candidates that are related to serum lipids, including high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG). The causal effects were primarily determined through inverse-variance weighting (IVW)-based analyses. RESULTS: Neither TG (odds ratio [OR] = 1.149; 95% confidence interval [CI], 0.887-1.489; P = 0.293) nor HDL-C (OR = 0.864; 95% CI, 0.718-1.041; P = 0.124) had causal effects on LBD. However, a causal relationship was identified between LDL-C and LBD (OR = 1.343; 95% CI, 1.094-1.649; P = 0.005), which remained significant (OR = 1.237; 95% CI, 1.015-1.508; P = 0.035) following adjustment for HDL-C and TG in multivariable MR. CONCLUSIONS: Elevated serum LDL-C increases the risk of LBD, while HDL-C and TG have no significant causal effects on LBD.


Assuntos
Doença por Corpos de Lewy , Análise da Randomização Mendeliana , Humanos , LDL-Colesterol , Fatores de Risco , Estudo de Associação Genômica Ampla , Doença por Corpos de Lewy/genética , Polimorfismo de Nucleotídeo Único/genética , Triglicerídeos , HDL-Colesterol
6.
Proc Natl Acad Sci U S A ; 118(14)2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33785600

RESUMO

The contraction of heart cells is controlled by the intermolecular signaling between L-type Ca2+ channels (LCCs) and ryanodine receptors (RyRs), and the nanodistance between them depends on the interaction between junctophilin-2 (JPH2) in the sarcoplasmic reticulum (SR) and caveolin-3 (CAV3) in the transversal tubule (TT). In heart failure, decreased expression of JPH2 compromises LCC-RyR communication leading to deficient blood-pumping power. In the present study, we found that JPH2 and CAV3 transcription was concurrently regulated by serum response factor (SRF) and myocardin. In cardiomyocytes from torpid ground squirrels, compared with those from euthermic counterparts, myocardin expression was up-regulated, which boosted both JPH2 and CAV3 expression. Transmission electron microscopic imaging showed that the physical coupling between TTs and SRs was tightened during hibernation and after myocardin overexpression. Confocal Ca2+ imaging under the whole-cell patch clamp condition revealed that these changes enhanced the efficiency of LCC-RyR intermolecular signaling and fully compensated the adaptive down-regulation of LCCs, maintaining the power of heart contraction while avoiding the risk of calcium overload during hibernation. Our finding not only revealed an essential molecular mechanism underlying the survival of hibernating mammals, but also demonstrated a "reverse model of heart failure" at the molecular level, suggesting a strategy for treating heart diseases.


Assuntos
Sinalização do Cálcio , Hibernação , Miócitos Cardíacos/metabolismo , Animais , Caveolinas/genética , Caveolinas/metabolismo , Células Cultivadas , Acoplamento Excitação-Contração , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Nucleares/sangue , Proteínas Nucleares/metabolismo , Sciuridae , Transativadores/sangue , Transativadores/metabolismo
7.
BMC Med Educ ; 24(1): 73, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243255

RESUMO

OBJECTIVE: The purpose of this study was to investigate the effectiveness of implementation of video feedback combined with peer role-playing (PRP) teaching method in medical undergraduates adopting problem-based learning (PBL) teaching mode. METHODS: The undergraduates of five-year clinical medicine who get enrollment of Wuhan local University from 2016 and 2018 were selected to be the research objects. The same grade level is randomly divided into several groups to carry out PBL, with 6-10 students in each group. Following the principle of voluntary participation, 34 students were enrolled in the study group and 33 students in the control group finally. The research regards group as the unit, and study report in group should be carried out to fulfill the research. In the study group, the students were asked to perform PRP report, and the report videos were used for feedback. At the same time, the control group reported by PPT, and the feedback was carried out according to the PPT. At the end of the study, the "Competency Improvement Satisfaction Questionnaire (CISQ)" was distributed to investigate students' satisfaction with this teaching method to improve their ability, Arizona Clinical Interview Score (ACIR) was administered in Chinese by a trained teacher unrelated using PRP method to assess students' clinical inquiry ability and communication skills, and theory test was performed to assess mastery of theoretical knowledge. RESULTS: The results show that the study group is superior to the control group in improving the interest of learning and the ability of independent learning, interpersonal communication and active problem solving. Although it is in terms of the confidence in becoming a real doctor and the ability of teamwork, language expression, clinical thinking cultivated, active knowledge acquired and understood that study group are better than the control group, the difference was not statistically significant. ACIR shows that the study group is significantly better than the control group in organization, timeline planning, and transition statements, openly questioning, smooth progress, and avoiding repetition, summarizing, understandable language, documentation and total score. There is no significant difference in eye contact and no interruption. The differences between the two groups are not statistically significant in terms of responsing to concerns, positive feedback, and additional questions. The theoretical test scores of the study group are significantly higher than those of the control group. CONCLUSION: Video feedback combined with peer role-playing teaching method implemented in medical undergraduates adopting PBL teaching mode is effective, it could stimulate interest in learning actively, improve interpersonal communication ability, improve learning efficiency and clinical knowledge and skills, and improve the confidence of becoming a real doctor. It is worthy of further research and promotion.


Assuntos
Estudantes de Medicina , Humanos , Retroalimentação , Aprendizagem , Grupo Associado , Aprendizagem Baseada em Problemas/métodos , Ensino
8.
Inflammopharmacology ; 32(1): 335-354, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38097885

RESUMO

BACKGROUND: The clinical efficacy and safety of intravenous immunoglobulin (IVIg) treatment for COVID-19 remain controversial. This study aimed to map the current status and gaps of available evidence, and conduct a meta-analysis to further investigate the benefit of IVIg in COVID-19 patients. METHODS: Electronic databases were searched for systematic reviews/meta-analyses (SR/MAs), primary studies with control groups, reporting on the use of IVIg in patients with COVID-19. A random-effects meta-analysis with subgroup analyses regarding study design and patient disease severity was performed. Our outcomes of interest determined by the evidence mapping, were mortality, length of hospitalization (days), length of intensive care unit (ICU) stay (days), number of patients requiring mechanical ventilation, and adverse events. RESULTS: We included 34 studies (12 SR/MAs, 8 prospective and 14 retrospective studies). A total of 5571 hospitalized patients were involved in 22 primary studies. Random-effects meta-analyses of very low to moderate evidence showed that there was little or no difference between IVIg and standard care or placebo in reducing mortality (relative risk [RR] 0.91; 95% CI 0.78-1.06; risk difference [RD] 3.3% fewer), length of hospital (mean difference [MD] 0.37; 95% CI - 2.56, 3.31) and ICU (MD 0.36; 95% CI - 0.81, 1.53) stays, mechanical ventilation use (RR 0.92; 95% CI 0.68-1.24; RD 2.8% fewer), and adverse events (RR 0.98; 95% CI 0.84-1.14; RD 0.5% fewer) of patients with COVID-19. Sensitivity analysis using a fixed-effects model indicated that IVIg may reduce mortality (RR 0.76; 95% CI 0.60-0.97), and increase length of hospital stay (MD 0.68; 95% CI 0.09-1.28). CONCLUSION: Very low to moderate certainty of evidence indicated IVIg may not improve the clinical outcomes of hospitalized patients with COVID-19. Given the discrepancy between the random- and fixed-effects model results, further large-scale and well-designed RCTs are warranted.


Assuntos
COVID-19 , Imunoglobulinas Intravenosas , Humanos , Imunoglobulinas Intravenosas/efeitos adversos , Estudos Prospectivos , Estudos Retrospectivos , Revisões Sistemáticas como Assunto
9.
Saudi Pharm J ; 32(7): 102124, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38933713

RESUMO

Natural products (NPs) play an irreplaceable role in the intervention of various diseases and have been considered a critical source of drug development. Many new pharmacodynamic compounds with potential clinical applications have recently been derived from NPs. These compounds range from small molecules to polysaccharides, polypeptides, proteins, self-assembled nanoparticles, and extracellular vesicles. This review summarizes various active substances found in NPs. The investigation of active substances in NPs can potentiate new drug development and promote the in-depth comprehension of the mechanism of action of NPs that can be beneficial in the prevention and treatment of human diseases.

10.
Metab Eng ; 75: 192-204, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36572334

RESUMO

Genome-scale target identification promises to guide microbial cell factory engineering for higher-titer production of biomolecules such as recombinant proteins (r-protein), but challenges remain due to the need not only for comprehensive genotypic perturbation but also in conjunction with high-throughput phenotypic screening strategies. Here, we developed a CRISPRi-microfluidics screening platform to systematically identify crucial gene targets that can be engineered to enhance r-protein secretion in Corynebacterium glutamicum. We created a CRISPR interference (CRISPRi) library containing 46,549 single-guide RNAs, where we aimed to unbiasedly target all genes for repression. Meanwhile, we developed a highly efficient droplet-based microfluidics system integrating the FlAsH-tetracysteine assay that enables screening of millions of strains to identify potential knockdowns conducive to nanobody VHH secretion. Among our highest-ranking candidates are a slew of previously unknown targets involved in transmembrane transport, amino-acid metabolism and redox regulation. Guided by these findings, we eventually constructed a hyperproducer for multiple proteins via combinatorial engineering of redox-response transcription factors. As the near-universal applicability of CRISPRi technology and the FlAsH-based screening platform, this procedure might be expanded to include a varied variety of microbial species and recombinant proteins.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Microfluídica , Proteínas Recombinantes/genética , Sistemas CRISPR-Cas/genética
11.
Biotechnol Bioeng ; 120(3): 778-792, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36477904

RESUMO

Solid plates have been used for microbial monoclonal isolation, cultivation, and colony picking since 1881. However, the process is labor- and resource-intensive for high-throughput requirements. Currently, several instruments have been integrated for automated and high-throughput picking, but complicated and expensive. To address these issues, we report a novel integrated platform, the single-cell microliter-droplet screening system (MISS Cell), for automated, high-throughput microbial monoclonal colony cultivation and picking. We verified the monoclonality of droplet cultures in the MISS Cell and characterized culture performance. Compared with solid plates, the MISS Cell generated a larger number of monoclonal colonies with higher initial growth rates using fewer resources. Finally, we established a workflow for automated high-throughput screening of Corynebacterium glutamicum using the MISS Cell and identified high glutamate-producing strains. The MISS Cell can serve as a universal platform to efficiently produce monoclonal colonies in high-throughput applications, overcoming the limitations of solid plates to promote rapid development in biotechnology.


Assuntos
Biotecnologia , Corynebacterium glutamicum , Ensaios de Triagem em Larga Escala
12.
World J Urol ; 41(6): 1563-1571, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37099197

RESUMO

PURPOSE: Few data are available regarding the nephrotoxicity of immune checkpoint inhibitor (ICI) combination therapy in advanced renal cell carcinoma (RCC). This study aimed to investigate the nephrotoxicity of ICI-based combination therapy versus standard of care sunitinib in patients with advanced RCC. METHODS: We searched Embase/PubMed/Cochrane Library for relevant randomized controlled trials (RCTs). Treatment-related nephrotoxicities including increase of creatinine and proteinuria were analyzed by Review Manager 5.4 software. RESULTS: Seven RCTs involving 5239 patients were included. The analysis showed that ICI combination therapy had similar risks of any grade (RR = 1.03, 95% CI: 0.77-1.37, P = 0.87) and grade 3-5 (RR = 1.48, 95% CI: 0.19-11.66, P = 0.71) increased creatinine compared with sunitinib monotherapy. However, ICI combination therapy was associated with significantly higher risks of any grade (RR = 2.33, 95% CI: 1.54-3.51, P < 0.0001) and grade 3-5 proteinuria (RR = 2.25, 95% CI: 1.21-4.17, P = 0.01). CONCLUSIONS: This meta-analysis suggests that ICI combination therapy shows more nephrotoxicity of proteinuria than sunitinib in advanced RCC, which deserves a high attention in the clinic.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Sunitinibe/efeitos adversos , Inibidores de Checkpoint Imunológico/efeitos adversos , Creatinina , Neoplasias Renais/patologia
13.
Nucleic Acids Res ; 49(3): 1263-1277, 2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-33503261

RESUMO

As an effective programmable DNA targeting tool, CRISPR-Cas9 system has been adopted in varieties of biotechnological applications. However, the off-target effects, derived from the tolerance towards guide-target mismatches, are regarded as the major problems in engineering CRISPR systems. To understand this, we constructed two sgRNA libraries carrying saturated single- and double-nucleotide mismatches in living bacteria cells, and profiled the comprehensive landscape of in vivo binding affinity of dCas9 toward DNA target guided by each individual sgRNA with particular mismatches. We observed a synergistic effect in seed, where combinatorial double mutations caused more severe activity loss compared with the two corresponding single mutations. Moreover, we found that a particular mismatch type, dDrG (D = A, T, G), only showed moderate impairment on binding. To quantitatively understand the causal relationship between mismatch and binding behaviour of dCas9, we further established a biophysical model, and found that the thermodynamic properties of base-pairing coupled with strand invasion process, to a large extent, can account for the observed mismatch-activity landscape. Finally, we repurposed this model, together with a convolutional neural network constructed based on the same mechanism, as a predictive tool to guide the rational design of sgRNA in bacterial CRISPR interference.


Assuntos
Proteína 9 Associada à CRISPR/metabolismo , RNA/metabolismo , Pareamento Incorreto de Bases , Sistemas CRISPR-Cas , DNA/metabolismo , Escherichia coli/genética , Modelos Genéticos , Ligação Proteica , RNA/química , Termodinâmica
14.
J Hum Nutr Diet ; 36(4): 1496-1506, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36321401

RESUMO

BACKGROUND: The association of selenium and cadmium with heart failure and mortality has not been thoroughly explored. METHODS: We analysed data from the National Health and Nutrition Examination Survey (NHANES) database over 12 years (1999-2000, 2003-2004 and 2011-2018), which includes blood selenium and cadmium. Multivariable logistic regression and Cox proportional hazards regression were used. RESULTS: In total, 15,689 participants were enrolled. The multivariate analysis showed that low blood selenium (odds ratio [OR] = 0.952, p < 0.001) and high blood cadmium (OR = 1.345, p < 0.001) were independent risk factors of heart failure. During 96802 person-year follow-up, 1697 deaths occurred. The multivariable adjusted hazard ratio (HR) for all-cause mortality was 0.82 (95% confidence interval [CI] = 0.71-0.95) for middle selenium levels and 0.76 (95% CI = 0.65-0.88) for high selenium levels compared to low selenium levels. Taking the low cadmium levels as reference, the multivariable adjusted HR for all-cause mortality among high cadmium levels was 1.68 (95% CI = 1.44-1.96). Furthermore, the association between selenium, cadmium and cardiovascular mortality was similar to that of all-cause mortality. A subgroup analysis of the study population showed that in individuals with heart failure, although selenium levels were not associated with risk of all-cause mortality, high selenium levels were associated with a lower risk of cardiovascular mortality (HR = 0.33, p = 0.0032). CONCLUSIONS: Low blood selenium and high blood cadmium were independent risk factors of heart failure. Blood selenium was inversely associated with all-cause mortality and cardiovascular mortality, whereas blood cadmium was positively associated with them. Furthermore, blood selenium was associated with a lower risk of cardiovascular mortality in individuals with heart failure.


Assuntos
Doenças Cardiovasculares , Insuficiência Cardíaca , Selênio , Humanos , Cádmio , Inquéritos Nutricionais , Fatores de Risco
15.
Euro Surveill ; 28(41)2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37824247

RESUMO

BackgroundTwo human cases of avian influenza A (H3N8) virus infection were reported in China in 2022.AimTo characterise H3N8 viruses circulating in China in September 2021-May 2022.MethodsWe sampled poultry and poultry-related environments in 25 Chinese provinces. After isolating H3N8 viruses, whole genome sequences were obtained for molecular and phylogenetic analyses. The specificity of H3N8 viruses towards human or avian receptors was assessed in vitro. Their ability to replicate in chicken and mice, and to transmit between guinea pigs was also investigated.ResultsIn total, 98 H3N8 avian influenza virus isolates were retrieved from 38,639 samples; genetic analysis of 31 representative isolates revealed 17 genotypes. Viruses belonging to 10 of these genotypes had six internal genes originating from influenza A (H9N2) viruses. These reassorted viruses could be found in live poultry markets and comprised the strains responsible for the two human infections. A subset of nine H3N8 viruses (including six reassorted) that replicated efficiently in mice bound to both avian-type and human-type receptors in vitro. Three reassorted viruses were shed by chickens for up to 9 days, replicating efficiently in their upper respiratory tract. Five reassorted viruses tested on guinea pigs were transmissible among these by respiratory droplets.ConclusionAvian H3N8 viruses with H9N2 virus internal genes, causing two human infections, occurred in live poultry markets in China. The low pathogenicity of H3N8 viruses in poultry allows their continuous circulation with potential for reassortment. Careful monitoring of spill-over infections in humans is important to strengthen early-warning systems and maintain influenza pandemic preparedness.


Assuntos
Vírus da Influenza A Subtipo H3N8 , Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Influenza Humana , Doenças das Aves Domésticas , Animais , Humanos , Camundongos , Cobaias , Influenza Humana/epidemiologia , Aves Domésticas , Influenza Aviária/epidemiologia , Vírus da Influenza A Subtipo H9N2/genética , Filogenia , Galinhas , China/epidemiologia , Doenças das Aves Domésticas/epidemiologia
16.
J Environ Manage ; 345: 118763, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37683385

RESUMO

Decentralized wastewater treatment warrants considerable development in numerous countries and regions. Owing to the unique characteristics of high ammonia nitrogen concentrations and low carbon/nitrogen ratio, nitrogen removal is a key challenge in treating expressway service area sewage. In this study, an anoxic/oxic-moving bed biofilm reactor (A/O-MBBR) and a traditional A/O bioreactor were continuously operated for 115 days and their outcomes were compared to investigate the enhancement effect of carriers on the total nitrogen removal (TN) for expressway service area sewage. Results revealed that A/O-MBBR required lower dissolved oxygen, exhibited higher tolerance toward harsh conditions, and demonstrated better shock load resistance than traditional A/O bioreactor. The TN removal load of A/O-MBBR reached 181.5 g‧N/(m3‧d), which was 15.24% higher than that of the A/O bioreactor. Furthermore, under load shock resistance, the TN removal load of A/O-MBBR still reached 327.0 g‧N/(m3‧d), with a TN removal efficiency of above 80%. Moreover, kinetics demonstrated that the denitrification rate of the A/O-MBBR was 121.9% higher than that of the A/O bioreactor, with the anoxic tank biofilm contributing 60.9% of the total denitrification rate. Community analysis results revealed that the genera OLB8, uncultured_f_Saprospiraceae and OLB12 were the dominant in biofilm loaded on carriers, and OLB8 was the key for enhanced denitrification. FAPROTAX and PICRUSt2 analyses confirmed that more bacteria associated with nitrogen metabolism were enriched by the A/O-MBBR carriers through full denitrification metabolic pathway and dissimilatory nitrate reduction pathway. This study offers a perspective into the development of cost-effective and high-efficiency treatment solutions for expressway service area sewage.


Assuntos
Biofilmes , Reatores Biológicos , Desnitrificação , Esgotos , Nitrogênio
17.
J Environ Manage ; 348: 119237, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37832290

RESUMO

Sulfide produced from sewers is considered one of the dominant threats to public health and sewer lifespan due to its toxicity and corrosiveness. In this study, we developed an environmentally friendly strategy for gaseous sulfide control by enriching indigenous sulfur-oxidizing bacteria (SOB) from sewer sediment. Ceramics acted as bio-carriers for immobilizing SOB for practical use in a lab-scale sewer reactor. 16 S rRNA gene sequences revealed that the SOB consortium was successfully enriched, with Thiobacillus, Pseudomonas, and Alcaligenes occupying a dominant abundance of 64.7% in the microbial community. Metabolic pathway analysis in different acclimatization stages indicates that microorganisms could convert thiosulfate and sulfide into elemental sulfur after enrichment and immobilization. A continuous experiment in lab-scale sewer reactors confirmed an efficient result for sulfide removal with hydrogen sulfide reduction of 43.9% and 85.1% under high-sulfur load and low-sulfur load conditions, respectively. This study shed light on the promising application for sewer sulfide control by biological sulfur oxidation strategy.


Assuntos
Sulfeto de Hidrogênio , Esgotos , Sulfetos/metabolismo , Bactérias/metabolismo , Enxofre , Oxirredução
18.
Nat Chem Biol ; 16(4): 440-449, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31873224

RESUMO

Indole signaling is an important cross-species communication pathway in the mammalian gut. In bacteria, upon induction by tryptophan, the molecular sensor (tnaC) controls indole biosynthesis by precisely coordinating dynamics of the corresponding macromolecular machineries during its transcription and translation. Our understanding of this regulatory program is still limited owing to its rapid dynamic nature. To address this shortcoming, we adopted a massively parallel profiling method to quantify the responses of 1,450 synthetic tnaC variants in the presence of three concentrations of tryptophan in living bacterial cells. The resultant dataset enabled us to comprehensively probe the key intermediate states of macromolecular machineries during the transcription and translation of tnaC. We also used modeling to provide a systems-level understanding of how these critical states collectively shape the output of this regulatory program quantitatively. A similar methodology will likely apply to other poorly understood dynamics-dependent cis-regulatory elements.


Assuntos
Proteínas de Escherichia coli/metabolismo , Indóis/metabolismo , Proteínas de Bactérias/metabolismo , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/fisiologia , Biossíntese de Proteínas/efeitos dos fármacos , Sinais Direcionadores de Proteínas , Ribossomos/metabolismo , Transdução de Sinais/fisiologia , Transcrição Gênica/efeitos dos fármacos , Triptofano/metabolismo
19.
BMC Gastroenterol ; 22(1): 521, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36526962

RESUMO

OBJECTIVES: Dysglycemia promotes the occurrence of fatty liver disease (FLD). However, the process is unclear. This study aimed to analyze the median time-to-onset, cumulative prevalence and influencing factors for the occurrence of FLD in people undergoing routine screening and evaluation. METHODS: Data from Karamay Central Hospital (September 2008-April 2017) were analyzed. Survival analysis was performed to calculate the median time and cumulative prevalence of FLD associated with normal and elevated fasting blood glucose (FBG) levels. Cox proportional hazards model was used to determine risk factors. RESULTS: A total of 31,154 participants were included in the two cohorts of this study, including 15,763 men. The mean age was 41.1 ± 12.2 years. There were 2230 patients (1725 male) in the elevated FBG group, the median age was 53 years (range 21-85 years), the median time-to-onset of FLD was 5.2 years. The incidence of FLD was 121/1000 person-years, and the 1-, 3-, 5-, and 7-year prevalence rates were 4%, 30%, 49%, and 64%, respectively. The normal FBG group included 28,924 participants (14,038 male), the median age was 40 years (range 17-87 years), and the corresponding values were as follows: 8.3 years, 66/1000 person-years, and 3%, 16%, 28%, and 41%, respectively. The Cox proportional hazards analysis revealed that age, blood pressure, FBG, body mass index and triglycerides were independent influencing factors for FLD in individuals (P < 0.05). CONCLUSIONS: Elevated FBG levels increase the risk of FLD and should be treated promptly.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Masculino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adolescente , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Índice de Massa Corporal , Fatores de Risco , Jejum , Glucose , Glicemia
20.
Biotechnol Appl Biochem ; 69(4): 1535-1544, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34269481

RESUMO

To tune the efficiency of oxidized cofactor recycling between alcohol dehydrogenase (ADH) and NADH oxidase (NOX) for the production of aromatic chiral alcohols, we designed and constructed four novel bifunctional fusion proteins composed of thermostable ADH and NOX from Thermococcus kodakarensis KOD1. ADH was linked to the N- or C-terminus of NOX with a typical rigid linker (EAAAK)3 and a flexible linker (GGGGS)3 , respectively. Compared with the parental enzymes, the NOX moieties in the four fusion proteins exhibited higher specific activities (141%-282%), while the ADH moieties exhibited varying levels of specific activity (69%-167%). All fusion proteins showed decreased affinities toward the cofactors, with increased Km values toward NADH (159%-406%) and NAD+ (202%-372%). In the enantioselective oxidation of (RS)-1-phenylethanol coupled with cofactor regeneration, the four fusion proteins displayed different positive and negative effects on the recycling efficiency of the oxidized cofactor. The two fusion proteins composed of NOX at the N-terminus exhibited higher total turnover numbers than the corresponding mixtures of individual enzymes with equal activities, particularly at low cofactor concentrations. These findings suggest high cofactor recycling efficiencies of the fusion proteins with appropriate design and their potential application in the biosynthesis of chiral alcohols.


Assuntos
Álcool Desidrogenase , NADH NADPH Oxirredutases , Álcool Desidrogenase/genética , Álcool Desidrogenase/metabolismo , Álcoois/metabolismo , Complexos Multienzimáticos , NAD/metabolismo , NADH NADPH Oxirredutases/genética , NADH NADPH Oxirredutases/metabolismo , Regeneração
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