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1.
Nature ; 605(7909): 325-331, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35418683

RESUMO

Cellular reprogramming can manipulate the identity of cells to generate the desired cell types1-3. The use of cell intrinsic components, including oocyte cytoplasm and transcription factors, can enforce somatic cell reprogramming to pluripotent stem cells4-7. By contrast, chemical stimulation by exposure to small molecules offers an alternative approach that can manipulate cell fate in a simple and highly controllable manner8-10. However, human somatic cells are refractory to chemical stimulation owing to their stable epigenome2,11,12 and reduced plasticity13,14; it is therefore challenging to induce human pluripotent stem cells by chemical reprogramming. Here we demonstrate, by creating an intermediate plastic state, the chemical reprogramming of human somatic cells to human chemically induced pluripotent stem cells that exhibit key features of embryonic stem cells. The whole chemical reprogramming trajectory analysis delineated the induction of the intermediate plastic state at the early stage, during which chemical-induced dedifferentiation occurred, and this process was similar to the dedifferentiation process that occurs in axolotl limb regeneration. Moreover, we identified the JNK pathway as a major barrier to chemical reprogramming, the inhibition of which was indispensable for inducing cell plasticity and a regeneration-like program by suppressing pro-inflammatory pathways. Our chemical approach provides a platform for the generation and application of human pluripotent stem cells in biomedicine. This study lays foundations for developing regenerative therapeutic strategies that use well-defined chemicals to change cell fates in humans.


Assuntos
Diferenciação Celular , Reprogramação Celular , Células-Tronco Pluripotentes Induzidas , Linhagem da Célula , Humanos , Células-Tronco Pluripotentes Induzidas/citologia
2.
Development ; 151(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38602507

RESUMO

CFAP58 is a testis-enriched gene that plays an important role in the sperm flagellogenesis of humans and mice. However, the effect of CFAP58 on bull semen quality and the underlying molecular mechanisms involved in spermatogenesis remain unknown. Here, we identified two single-nucleotide polymorphisms (rs110610797, A>G and rs133760846, G>T) and one indel (g.-1811_ g.-1810 ins147bp) in the promoter of CFAP58 that were significantly associated with semen quality of bulls, including sperm deformity rate and ejaculate volume. Moreover, by generating gene knockout mice, we found for the first time that the loss of Cfap58 not only causes severe defects in the sperm tail, but also affects the manchette structure, resulting in abnormal sperm head shaping. Cfap58 deficiency causes an increase in spermatozoa apoptosis. Further experiments confirmed that CFAP58 interacts with IFT88 and CCDC42. Moreover, it may be a transported cargo protein that plays a role in stabilizing other cargo proteins, such as CCDC42, in the intra-manchette transport/intra-flagellar transport pathway. Collectively, our findings reveal that CFAP58 is required for spermatogenesis and provide genetic markers for evaluating semen quality in cattle.


Assuntos
Análise do Sêmen , Sêmen , Humanos , Bovinos , Masculino , Animais , Camundongos , Cabeça do Espermatozoide , Espermatozoides , Camundongos Knockout
3.
Small ; 20(29): e2310825, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38342581

RESUMO

Bifunctional electrocatalysts with excellent activity and durability are highly desirable for alkaline overall water splitting, yet remain a significant challenge. In this contribution, palm-like Mo5N6/Ni3S2 heterojunction arrays anchored in conductive Ni foam (denoted as Mo5N6-Ni3S2 HNPs/NF) are developed. Benefiting from the optimized electronic structure configuration, hierarchical branched structure and abundant heterogeneous interfaces, the as-synthesized Mo5N6-Ni3S2 HNPs/NF electrode exhibits remarkably stable bifunctional electrocatalytic activity in 1 m KOH solution. It only requires ultralow overpotentials of 59 and 190 mV to deliver a current density of 10 mA cm-2 for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in 1 m KOH solution, respectively. Importantly, the overall water splitting electrolyzer assembled by Mo5N6-Ni3S2 HNPs/NF exhibits an exceptionally low cell voltage (1.48 V@10 mA cm-2) and outstanding durability, surpassing most of the reported Ni-based bifunctional materials. Density functional theory (DFT) further confirms the heterostructure can optimize the Gibbs free energies of H and O-containing intermediates (OH, O, OOH) during HER and OER processes, thereby accelerating the catalytic kinetics of electrochemical water splitting. The findings provide a new design strategy toward low-cost and excellent catalysts for overall water splitting.

4.
Cardiovasc Diabetol ; 23(1): 222, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926737

RESUMO

BACKGROUND: Previous studies have shown that an elevated triglyceride-glucose (TyG) index was associated with all-cause mortality in both general adult individuals and critically ill adult patients. However, the relationship between the TyG index and clinical prognosis in pediatric patients admitted to the intensive care unit (ICU) remains unknown. We aimed to investigate the association of the TyG index with in-hospital all-cause mortality in critically ill pediatric patients. METHODS: A total of 5706 patients in the Pediatric Intensive Care database were enrolled in this study. The primary outcome was 30-day in-hospital all-cause mortality, and secondary outcome was 30-day in-ICU all-cause mortality. The restricted cubic spline (RCS) curves and two-piecewise multivariate Cox hazard regression models were performed to explore the relationship between the TyG index and outcomes. RESULTS: The median age of the study population was 20.5 [interquartile range (IQR): 4.8, 63.0] months, and 3269 (57.3%) of the patients were male. The mean TyG index level was 8.6 ± 0.7. A total of 244 (4.3%) patients died within 30 days of hospitalization during a median follow-up of 11 [7, 18] days, and 236 (4.1%) patients died in ICU within 30 days of hospitalization during a median follow-up of 6 [3, 11] days. The RCS curves indicated a U-shape association between the TyG index and 30-day in-hospital and in-ICU all-cause mortality (both P values for non-linear < 0.001). The risk of 30-day in-hospital all-cause mortality was negatively correlated with the TyG index until it bottoms out at 8.6 (adjusted hazard ratio [HR], 0.72, 95% confidence interval [CI] 0.55-0.93). However, when the TyG index was higher than 8.6, the risk of primary outcome increased significantly (adjusted HR, 1.51, 95% CI 1.16-1.96]). For 30-day in-ICU all-cause mortality, we also found a similar relationship (TyG < 8.6: adjusted HR, 0.75, 95% CI 0.57-0.98; TyG ≥ 8.6: adjusted HR, 1.42, 95% CI 1.08-1.85). Those results were consistent in subgroups and various sensitivity analysis. CONCLUSIONS: Our study showed that the association between the TyG index and 30-day in-hospital and in-ICU all-cause mortality was nonlinear U-shaped, with a cutoff point at the TyG index of 8.6 in critically ill pediatric patients. Our findings suggest that the TyG index may be a novel and important factor for the short-term clinical prognosis in pediatric patients.


Assuntos
Biomarcadores , Glicemia , Causas de Morte , Estado Terminal , Bases de Dados Factuais , Mortalidade Hospitalar , Unidades de Terapia Intensiva Pediátrica , Triglicerídeos , Humanos , Masculino , Estado Terminal/mortalidade , Feminino , Estudos Retrospectivos , Glicemia/metabolismo , Triglicerídeos/sangue , Fatores de Risco , Lactente , Pré-Escolar , Fatores de Tempo , Medição de Risco , Biomarcadores/sangue , Prognóstico , Fatores Etários , Criança , Valor Preditivo dos Testes , Mortalidade da Criança
5.
CMAJ ; 196(27): E931-E939, 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39134317

RESUMO

BACKGROUND: Hepatitis B virus (HBV) infection is a common cause of liver-related morbidity and mortality. Evidence suggests that angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) decrease liver fibrosis, an intermediate step between liver injury and hepatocellular carcinoma (HCC). Our aim was to investigate the association between the use of ACEIs and ARBs on incident HCC and liver-related mortality among patients with HBV infection. METHODS: We conducted a population-based study on a new-user cohort of patients seen at 24 hospitals across China. We included adult patients with HBV infection who started ACEIs or ARBs (ACEIs/ARBs), or calcium channel blockers or thiazide diuretics (CCBs/THZs) from January 2012 to December 2022. The primary outcome was incident HCC; secondary outcomes were liver-related mortality and new-onset cirrhosis. We used propensity score matching and Cox proportional hazards regression to estimate the hazard ratio (HR) and 95% confidence intervals (CIs) of study outcomes. RESULTS: Among 32 692 eligible patients (median age 58 [interquartile range (IQR) 48-68] yr, and 18 804 male [57.5%]), we matched 9946 pairs of patients starting ACEIs/ARBs or CCBs/THZs. During a mean follow-up of 2.3 years, the incidence rate of HCC per 1000 person-years was 4.11 and 5.94 among patients who started ACEIs/ARBs and CCBs/THZs, respectively, in the matched cohort. Use of ACEIs/ARBs was associated with lower risks of incident HCC (HR 0.66, 95% CI 0.50-0.86), liver-related mortality (HR 0.77, 95% CI 0.64-0.93), and new-onset cirrhosis (HR 0.81, 95% CI 0.70-0.94). INTERPRETATION: In this cohort of patients with HBV infection, new users of ACEIs/ARBs had a lower risk of incident HCC, liver-related mortality, and new-onset cirrhosis than new users of CCBs/THZs.


Assuntos
Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/epidemiologia , Masculino , Neoplasias Hepáticas/epidemiologia , Feminino , Pessoa de Meia-Idade , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Idoso , Antagonistas de Receptores de Angiotensina/uso terapêutico , Antagonistas de Receptores de Angiotensina/efeitos adversos , China/epidemiologia , Hepatite B/complicações , Cirrose Hepática , Incidência , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Pontuação de Propensão , Modelos de Riscos Proporcionais , Fatores de Risco , Sistema Renina-Angiotensina/efeitos dos fármacos
6.
BMC Cardiovasc Disord ; 24(1): 262, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769510

RESUMO

BACKGROUND: Optical coherence tomography (OCT) guidance in percutaneous coronary intervention (PCI) has been shown to improve procedural outcomes. However, evidence supporting its superiority over angiography-guided PCI in terms of clinical outcomes is still emerging and limited. This study aimed to compare the efficacy and safety of OCT-guided PCI versus angiography-guided PCI in patients with coronary artery disease (CAD). METHODS: A systematic search of electronic databases was conducted to identify randomized control trials (RCTs) comparing the clinical outcomes of OCT-guided and angiography-guided PCI in patients with CAD. Clinical endpoints including all-cause mortality, myocardial infarction (MI), target lesion revascularization (TLR), stent thrombosis and major adverse cardiac events (MACE) were assessed. RESULTS: Eleven RCTs, comprising 2,699 patients in the OCT-guided group and 2,968 patients in the angiography-guided group met inclusion criteria. OCT-guided PCI was associated with significantly lower rates of cardiovascular death(RR 0.56; 95%CI: 0.32-0.98; p = 0.04; I2 = 0%), stent thrombosis(RR 0.56; 95%CI: 0.33-0.95; p = 0.03; I2 = 0%), and MACE (RR 0.79; 95%CI: 0.66-0.95; p = 0.01; I2 = 5%). The incidence of all-cause death (RR 0.71; 95%CI: 0.49-1.02; p = 0.06; I2 = 0%), myocardial infarction (RR 0.86; 95%CI: 0.67-1.10; p = 0.22; I2 = 0%) and TLR (RR 0.98; 95%CI: 0.73-1.33; p = 0.91; I2 = 0%) was non-significantly lower in the OCT-guided group. CONCLUSIONS: Among patients undergoing PCI, OCT-guided PCI was associated with lower incidences of cardiovascular death, stent thrombosis and MACE compared to angiography-guided PCI. TRIAL REGISTRATION: PROSPERO registration number: CRD42023484342.


Assuntos
Angiografia Coronária , Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Valor Preditivo dos Testes , Ensaios Clínicos Controlados Aleatórios como Assunto , Tomografia de Coerência Óptica , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/instrumentação , Intervenção Coronária Percutânea/mortalidade , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Doença da Artéria Coronariana/terapia , Resultado do Tratamento , Fatores de Risco , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Vasos Coronários/diagnóstico por imagem , Trombose Coronária/diagnóstico por imagem , Trombose Coronária/etiologia
7.
J Am Soc Nephrol ; 34(7): 1253-1263, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36977125

RESUMO

SIGNIFICANCE STATEMENT: Serum creatinine is not a sensitive biomarker for neonatal AKI because it is confounded by maternal creatinine level, gestational age, and neonatal muscle mass. In this multicenter cohort study of 52,333 hospitalized Chinese neonates, the authors proposed serum cystatin C-related criteria (CyNA) for neonatal AKI. They found that cystatin C (Cys-C) is a robust and sensitive biomarker for identifying AKI in neonates who are at an elevated risk of in-hospital mortality and that CyNA detects 6.5 times as many cases as the modified Kidney Disease Improving Global Outcomes creatinine criteria. They also show that AKI can be detected using a single test of Cys-C. These findings suggest that CyNA shows promise as a powerful and easily applicable tool for detecting AKI in neonates. BACKGROUND: Serum creatinine is not a sensitive biomarker for AKI in neonates. A better biomarker-based criterion for neonatal AKI is needed. METHODS: In this large multicenter cohort study, we estimated the upper normal limit (UNL) and reference change value (RCV) of serum cystatin C (Cys-C) in neonates and proposed cystatin C-based criteria (CyNA) for detecting neonatal AKI using these values as the cutoffs. We assessed the association of CyNA-detected AKI with the risk of in-hospital death and compared CyNA performance versus performance of modified Kidney Disease Improving Global Outcomes (KDIGO) creatinine criteria. RESULTS: In this study of 52,333 hospitalized neonates in China, Cys-C level did not vary with gestational age and birth weight and remained relatively stable during the neonatal period. CyNA criteria define AKI by a serum Cys-C of ≥2.2 mg/L (UNL) or an increase in Cys-C of ≥25% (RCV) during the neonatal period. Among 45,839 neonates with measurements of both Cys-C and creatinine, 4513 (9.8%) had AKI detected by CyNA only, 373 (0.8%) by KDIGO only, and 381 (0.8%) by both criteria. Compared with neonates without AKI by both criteria, neonates with AKI detected by CyNA alone had an increased risk of in-hospital mortality (hazard ratio [HR], 2.86; 95% confidence interval [95% CI], 2.02 to 4.04). Neonates with AKI detected by both criteria had an even higher risk of in-hospital mortality (HR, 4.86; 95% CI, 2.84 to 8.29). CONCLUSIONS: Serum Cys-C is a robust and sensitive biomarker for detecting neonatal AKI. Compared with modified KDIGO creatinine criteria, CyNA is 6.5 times more sensitive in identifying neonates at elevated risk of in-hospital mortality.


Assuntos
Injúria Renal Aguda , Cistatina C , Recém-Nascido , Humanos , Estudos de Coortes , Creatinina , Estudos Prospectivos , Mortalidade Hospitalar , Biomarcadores
8.
Angew Chem Int Ed Engl ; 63(22): e202403365, 2024 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-38454191

RESUMO

Meroterpenoids of the ochraceopones family featuring a linear tetracyclic scaffold exhibit exceptional antiviral and anti-inflammatory activities. The biosynthetic pathway and chemical logic to generate this linear tetracycle, however, remain unknown. In this study, we identified and characterized all biosynthetic enzymes to afford ochraceopones and elucidated the complete biosynthetic pathway. We demonstrated that the linear tetracyclic scaffold of ochraceopones was derived from an angular tetracyclic precursor. A multifunctional cytochrome P450 OchH was validated to catalyze the free-radical-initiated carbon-carbon bond cleavage of the angular tetracycle. Then, a new carbon-carbon bond was verified to be constructed using a new aldolase OchL, which catalyzes an intramolecular aldol reaction to form the linear tetracycle. This carbon-carbon bond fragmentation and aldol reaction cascade features an unprecedented strategy for converting a common angular tetracycle to a distinctive linear tetracyclic scaffold in meroterpenoid biosynthesis.


Assuntos
Carbono , Sistema Enzimático do Citocromo P-450 , Carbono/química , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/química , Estrutura Molecular , Terpenos/química , Terpenos/metabolismo , Aldeídos/química , Aldeídos/metabolismo , Biocatálise
9.
Am J Kidney Dis ; 81(4): 416-424.e1, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36252881

RESUMO

RATIONALE & OBJECTIVE: Challenges in achieving valid risk prediction and stratification impede treatment decisions and clinical research design for patients with glomerular diseases. This study evaluated whether chronic histologic changes, when complementing other clinical data, improved the prediction of disease outcomes across a diverse group of glomerular diseases. STUDY DESIGN: Multicenter retrospective cohort study. SETTING & PARTICIPANTS: 4,982 patients with biopsy-proven glomerular disease who underwent native biopsy at 8 tertiary care hospitals across China in 2004-2020. NEW PREDICTORS & ESTABLISHED PREDICTORS: Chronicity scores depicted as 4 categories of histological chronic change, as well as baseline clinical and demographic variables. OUTCOME: Progression of glomerular disease defined as a composite of kidney failure or a ≥40% decrease in estimated glomerular filtration rate from the measurement at the time of biopsy. ANALYTICAL APPROACH: Multivariable Cox proportional hazard models. The performance of predictive models was evaluated by C statistic, time-dependent area under the receiver operating characteristic curve (AUROC), net reclassification index, integrated discrimination index, and calibration plots. RESULTS: The derivation and validation cohorts included 3,488 and 1,494 patients, respectively. During a median of 31 months of follow-up, a total of 444 (8.9%) patients had disease progression in the 2 cohorts. For prediction of the 2-year risk of disease progression, the AUROC of the model combining chronicity score and the Kidney Failure Risk Equation (KFRE) in the validation cohort was 0.76 (95% CI, 0.65-0.87); in comparison with the KFRE model (AUROC, 0.68 [95% CI, 0.56-0.79]), the combined model was significantly better (P = 0.04). The combined model also had a better fit, with a lower Akaike information criterion and a significant improvement in reclassification as assessed by the integrated discrimination improvements and net reclassification improvements. Similar improvements in predictive performance were observed in subgroup and sensitivity analyses. LIMITATIONS: Selection bias, relatively short follow-up, lack of external validation. CONCLUSIONS: Adding histologic chronicity scores to the KFRE model improved the prediction of kidney disease progression at the time of kidney biopsy in patients with glomerular diseases. PLAIN-LANGUAGE SUMMARY: Risk prediction and stratification remain big challenges for treatment decisions and clinical research design for patients with glomerular diseases. The extent of chronic changes is an important component of kidney biopsy evaluations in glomerular disease. In this large multicenter cohort including 4,982 Chinese adults undergoing native kidney biopsy, we evaluated whether histologic chronicity scores, when added to clinical data, could improve the prediction of disease prognosis for a diverse set of glomerular diseases. We observed that adding histologic chronicity scores to the kidney failure risk equation improved the prediction of kidney disease progression at the time of kidney biopsy in patients with glomerular diseases.


Assuntos
Nefropatias , Insuficiência Renal Crônica , Insuficiência Renal , Adulto , Humanos , Estudos de Coortes , Estudos Retrospectivos , Progressão da Doença , Rim/patologia , Nefropatias/patologia , Insuficiência Renal/patologia , Taxa de Filtração Glomerular , Biópsia , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/patologia
10.
Cardiovasc Diabetol ; 22(1): 58, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36927705

RESUMO

BACKGROUND: Previous studies showed that the triglyceride-glucose (TyG) index was a better predictor of adverse cardiovascular events than triglycerides or fasting blood glucose alone. However, few studies have focused on new-onset hypertension. We aimed to explore the association of TyG index with new-onset hypertension in Chinese adults. METHODS: A total of 4,600 participants who underwent at least 2 rounds of visits from 2009 to 2015 in the China Health and Nutrition Survey were enrolled in this study. Our outcome of interest was new-onset hypertension. Multivariate Cox hazard regression models and restricted cubic spline were performed to explore the relationship between TyG index and new-onset hypertension. RESULTS: The mean (standard deviation, SD) age of the study population was 48.1 (13.6) years, and 2058 (44.7%) of the participants were men. The mean (SD) TyG index level was 8.6 (0.7). A total of 1,211 (26.3%) participants developed new-onset hypertension during a median (interquartile range) follow-up duration of 6.0 (2.0-6.1) years. The incidences of new-onset hypertension were 18.1%, 25.3%, 28.5%, and 33.4% by quartiles of TyG index [from quartile 1 (Q1) to Q4], respectively. The Cox model showed that high levels of TyG index were significantly associated with increased risk of new-onset hypertension (adjusted hazard ratio [aHR]: 1.29, 95% confidence interval [CI] 1.07-1.55, Q2; aHR, 1.24, 95% CI 1.03-1.49, Q3; aHR, 1.50, 95% CI 1.22-1.84, Q4) compared with Q1. Consistently, as a continuous variable, for every 1.0 increase in TyG index, there was a 17% increase in the risk of new-onset hypertension (aHR, 1.17; 95% CI 1.04-1.31). The associations were consistent in various subgroups and sensitivity analysis. The dose-response curve indicated a positive, linear association between TyG index and the risk of new-onset hypertension. CONCLUSIONS: High TyG index was significantly associated with an increased risk of new-onset hypertension among Chinese adults. Our findings suggest that maintaining a relatively low level of TyG index might be effective in the primary prevention of hypertension.


Assuntos
Hipertensão , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Feminino , Estudos de Coortes , Hipertensão/diagnóstico , Hipertensão/epidemiologia , China/epidemiologia , Glucose , Triglicerídeos , Glicemia , Fatores de Risco , Biomarcadores
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