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BACKGROUND: The key role of thrombospondin 1 (THBS1) in the pathogenesis of acute-on-chronic liver failure (ACLF) is unclear. Here, we present a transcriptome approach to evaluate THBS1 as a potential biomarker in ACLF disease pathogenesis. METHODS: Biobanked peripheral blood mononuclear cells (PBMCs) from 330 subjects with hepatitis B virus (HBV)-related etiologies, including HBV-ACLF, liver cirrhosis (LC), and chronic hepatitis B (CHB), and normal controls (NC) randomly selected from the Chinese Group on the Study of Severe Hepatitis B (COSSH) prospective multicenter cohort underwent transcriptome analyses (ACLF = 20; LC = 10; CHB = 10; NC = 15); the findings were externally validated in participants from COSSH cohort, an ACLF rat model and hepatocyte-specific THBS1 knockout mice. RESULTS: THBS1 was the top significantly differentially expressed gene in the PBMC transcriptome, with the most significant upregulation in ACLF, and quantitative polymerase chain reaction (ACLF = 110; LC = 60; CHB = 60; NC = 45) was used to verify that THBS1 expression corresponded to ACLF disease severity outcome, including inflammation and hepatocellular apoptosis. THBS1 showed good predictive ability for ACLF short-term mortality, with an area under the receiver operating characteristic curve (AUROC) of 0.8438 and 0.7778 at 28 and 90 days, respectively. Enzyme-linked immunosorbent assay validation of the plasma THBS1 using an expanded COSSH cohort subjects (ACLF = 198; LC = 50; CHB = 50; NC = 50) showed significant correlation between THBS1 with ALT and γ-GT (P = 0.01), and offered a similarly good prognostication predictive ability (AUROC = 0.7445 and 0.7175) at 28 and 90 days, respectively. ACLF patients with high-risk short-term mortality were identified based on plasma THBS1 optimal cut-off value (< 28 µg/ml). External validation in ACLF rat serum and livers confirmed the functional association between THBS1, the immune response and hepatocellular apoptosis. Hepatocyte-specific THBS1 knockout improved mouse survival, significantly repressed major inflammatory cytokines, enhanced the expression of several anti-inflammatory mediators and impeded hepatocellular apoptosis. CONCLUSIONS: THBS1 might be an ACLF disease development-related biomarker, promoting inflammatory responses and hepatocellular apoptosis, that could provide clinicians with a new molecular target for improving diagnostic and therapeutic strategies.
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Insuficiência Hepática Crônica Agudizada , Trombospondina 1 , Animais , Humanos , Camundongos , Ratos , Biomarcadores , Vírus da Hepatite B , Inflamação , Leucócitos Mononucleares , Cirrose Hepática , Estudos Prospectivos , Trombospondina 1/genéticaRESUMO
BACKGROUND: Hepatitis B-related acute-on-chronic liver failure (HBV-ACLF) has a high short-term mortality. This study aimed to determine the diagnostic and prognostic role of MER tyrosine kinase (MERTK) in HBV-ACLF patients. METHODS: Transcriptomics analysis evaluated MERTK expression and function during disease progression. The diagnostic and prognostic significance of MERTK for HBV-ACLF patients were verified by ELISA, the area under the receiver operating characteristic curve (AUROC) analysis, and immunohistochemistry (IHC) of liver tissues. RESULTS: MERTK mRNA was highly expressed in the HBV-ACLF compared to the liver cirrhosis (LC), chronic hepatitis B (CHB) and normal controls (NC) groups. Elevated MERTK mRNA predicted poor prognosis for HBV-ACLF at 28/90 days (AUROCs=0.814/0.731). Functional analysis showed MERTK was significantly associated with TLR and inflammatory signaling, and several key biological processes. External validation with 285 plasma subjects confirmed the high diagnostic accuracy of plasma MERTK for HBV-ACLF (AUROC=0.859) and potential prognostic value for 28/90-day mortality rates (AUROC=0.673 and 0.644, respectively). Risk stratification analysis indicated higher mortality risk for patients with plasma MERTK level above the cut-off value. Moreover, IHC staining showed increasing MERTK expression from NC, CHB and LC to HBV-ACLF patients. CONCLUSIONS: MERTK shows promise as a candidate biomarker for early diagnosis and prognosis of HBV-ACLF.
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Background: Liver transplantation (LT) is an effective therapy for acute-on-chronic liver failure (ACLF) but is limited by organ shortages. We aimed to identify an appropriate score for predicting the survival benefit of LT in HBV-related ACLF patients. Methods: Hospitalized patients with acute deterioration of HBV-related chronic liver disease (n = 4577) from the Chinese Group on the Study of Severe Hepatitis B (COSSH) open cohort were enrolled to evaluate the performance of five commonly used scores for predicting the prognosis and transplant survival benefit. The survival benefit rate was calculated to reflect the extended rate of the expected lifetime with vs. without LT. Findings: In total, 368 HBV-ACLF patients received LT. They showed significantly higher 1-year survival than those on the waitlist in both the entire HBV-ACLF cohort (77.2%/52.3%, p < 0.001) and the propensity score matching cohort (77.2%/27.6%, p < 0.001). The area under the receiver operating characteristic curve (AUROC) showed that the COSSH-ACLF II score performed best (AUROC 0.849) at identifying the 1-year risk of death on the waitlist and best (AUROC 0.864) at predicting 1-year outcome post-LT (COSSH-ACLFs/CLIF-C ACLFs/MELDs/MELD-Nas: AUROC 0.835/0.825/0.796/0.781; all p < 0.05). The C-indexes confirmed the high predictive value of COSSH-ACLF IIs. Survival benefit rate analyses showed that patients with COSSH-ACLF IIs 7-10 had a higher 1-year survival benefit rate from LT (39.2%-64.3%) than those with score <7 or >10. These results were prospectively validated. Interpretation: COSSH-ACLF IIs identified the risk of death on the waitlist and accurately predicted post-LT mortality and survival benefit for HBV-ACLF. Patients with COSSH-ACLF IIs 7-10 derived a higher net survival benefit from LT. Funding: This study was supported by the National Natural Science Foundation of China (No. 81830073, No. 81771196) and the National Special Support Program for High-Level Personnel Recruitment (Ten-thousand Talents Program).
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Early diagnosis and prediction of hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is important to reduce mortality. This study aimed to assess the diagnostic and predictive value of serum ferritin (SF) in HBV-ACLF patients. Clinical data from 1905 hospitalized patients with acute deterioration of HBV-related chronic liver diseases were analyzed to explore the association between SF and ACLF. A co-expression network based on transcriptomics data for 20 HBV-ACLF patients was constructed to investigate biological processes related to ferritin. Of 1270 patients in the derivation group, 440 and 830 were diagnosed with and without ACLF, respectively, based on Chinese Group on the Study of Severe Hepatitis B-ACLF criteria. SF levels showed high diagnostic accuracy (area under the receiver operating characteristic [AUROC]: 0.820) for ACLF at admission. In patients with ACLF, SF was associated with liver and coagulation failure. In patients without ACLF, SF predicted risk for 28-day progression to ACLF (AUROC: 0.808). A validation group of 635 patients confirmed the above results. Moreover, SF was significantly associated with the immune response based on transcriptomics analysis. SF is a potential diagnostic and predictive marker for HBV-ACLF and might play a crucial role in immune disorders in HBV-ACLF.
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Insuficiência Hepática Crônica Agudizada , Hepatite B Crônica , Hepatite B , Humanos , Vírus da Hepatite B/genética , Hepatite B Crônica/complicações , Hepatite B Crônica/diagnóstico , Insuficiência Hepática Crônica Agudizada/diagnóstico , Prognóstico , Hepatite B/complicaçõesRESUMO
BACKGROUND & AIMS: Acute-on-chronic liver failure (ACLF) is a life-threatening syndrome with rapid progression. This study aimed to develop and validate a prognostic score to predict the onset of ACLF in hepatitis B virus (HBV) etiology. METHODS: The prospective clinical data of 1373 patients with acute deterioration of HBV-related chronic liver disease were used to identify clinical characteristics and develop a prognostic score for the onset of ACLF. RESULTS: Of the patients assessed using the Chinese Group on the Study of Severe Hepatitis B (COSSH)-ACLF criteria, 903 patients with non-ACLF at admission (1 received transplantation at 5 days) were stratified: 71 with progression to ACLF and 831 without progression to ACLF at 7 days. Four predictors (total bilirubin, international normalized ratio, alanine aminotransferase, and ferritin) were associated significantly with ACLF onset at 7 days. The COSSH-onset-ACLF score was constituted as follows: (0.101 × ln [alanine aminotransferase] + 0.819 × ln [total bilirubin] + 2.820 × ln [international normalized ratio] + 0.016 × ln [ferritin]). The C-indexes of the new score for 7-/14-/28-day onset (0.928/0.925/0.913) were significantly higher than those of 5 other scores (Chronic Liver Failure Consortium ACLF development score/Model for End-stage Liver Disease score/Model for End-stage Liver Disease sodium score/COSSH-ACLF score/Chronic liver failure Consortium ACLF score; all P < .001). The improvement in predictive errors, time-dependent receiver operating characteristic, probability density function evaluation, and calibration curves of the new score showed the highest predictive value for ACLF onset at 7/14/28 days. Risk stratification of the new score showed 2 strata with high and low risk (≥6.3/<6.3) of ACLF onset. The external validation group further confirmed the earlier results. CONCLUSIONS: A new prognostic score based on 4 predictors can accurately predict the 7-/14-/28-day onset of ACLF in patients with acute deterioration of HBV-related chronic liver disease and might be used to guide clinical management.
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Insuficiência Hepática Crônica Agudizada , Doença Hepática Terminal , Hepatite B Crônica , Hepatite B , Humanos , Vírus da Hepatite B , Doença Hepática Terminal/complicações , Hepatite B Crônica/complicações , Insuficiência Hepática Crônica Agudizada/complicações , Estudos Prospectivos , Alanina Transaminase , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença , Hepatite B/complicações , Bilirrubina , Curva ROCRESUMO
The aim of this study was to explore whether citizens' scientific interest and self-understanding relate to their learning enjoyment and self-efficacy in science. The sample participants consisted of 1,657 Taiwanese citizens ranging from 18 to 70 years of age. All participants were asked to complete the 2018 "Taiwan Citizens Science and Technology Literacy Survey" to assess their scientific interest, scientific self-understanding, science learning enjoyment, and scientific self-efficacy. Multiple regression models were used to analyze the data. The important findings included: (1) scientific interest was the most important predictor of science learning enjoyment, while scientific self-understanding was the most important predictor of scientific self-efficacy; and (2) the effects of scientific interest on self-understanding and the effect of science learning enjoyment on scientific self-efficacy each were significantly moderated by respondents' age, with stronger relationships observed in younger citizens than older citizens. This study provides insight into Taiwanese citizens' scientific learning enjoyment and self-efficacy and also informs potential governmental policies and/or societal practices that could be considered to promote scientific literacy.
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OBJECTIVE: Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) pathophysiology remains unclear. This study aims to characterise the molecular basis of HBV-ACLF using transcriptomics. METHODS: Four hundred subjects with HBV-ACLF, acute-on-chronic hepatic dysfunction (ACHD), liver cirrhosis (LC) or chronic hepatitis B (CHB) and normal controls (NC) from a prospective multicentre cohort were studied, and 65 subjects (ACLF, 20; ACHD, 10; LC, 10; CHB, 10; NC, 15) among them underwent mRNA sequencing using peripheral blood mononuclear cells (PBMCs). RESULTS: The functional synergy analysis focusing on seven bioprocesses related to the PBMC response and the top 500 differentially expressed genes (DEGs) showed that viral processes were associated with all disease stages. Immune dysregulation, as the most prominent change and disorder triggered by HBV exacerbation, drove CHB or LC to ACHD and ACLF. Metabolic disruption was significant in ACHD and severe in ACLF. The analysis of 62 overlapping DEGs further linked the HBV-based immune-metabolism disorder to ACLF progression. The signatures of interferon-related, neutrophil-related and monocyte-related pathways related to the innate immune response were significantly upregulated. Signatures linked to the adaptive immune response were downregulated. Disruptions of lipid and fatty acid metabolism were observed during ACLF development. External validation of four DEGs underlying the aforementioned molecular mechanism in patients and experimental rats confirmed their specificity and potential as biomarkers for HBV-ACLF pathogenesis. CONCLUSIONS: This study highlights immune-metabolism disorder triggered by HBV exacerbation as a potential mechanism of HBV-ACLF and may indicate a novel diagnostic and treatment target to reduce HBV-ACLF-related mortality.
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Insuficiência Hepática Crônica Agudizada/patologia , Hepatite B Crônica/complicações , Leucócitos Mononucleares/imunologia , Insuficiência Hepática Crônica Agudizada/virologia , Imunidade Adaptativa , Adulto , Animais , Estudos de Casos e Controles , DNA Viral/sangue , Feminino , Vírus da Hepatite B , Humanos , Imunidade Inata , Masculino , Metaboloma , Pessoa de Meia-Idade , Estudos Prospectivos , Ratos , TranscriptomaRESUMO
Acute-on-chronic liver failure (ACLF) is clinical syndrome with high mortality rate. This study aimed to perform detailed transcriptomic analysis in liver cirrhosis-based ACLF rats to elucidate ACLF pathogenesis. ACLF was induced by combined porcine serum with D-galactosamine and lipopolysaccharide. Gene expression profile of liver tissues from ACLF rats was generated by transcriptome sequencing to reveal the molecular mechanism. ACLF rats successfully developed with typical characteristics. Total of 2,354/3,576 differentially expressed genes were identified when ACLF was compared to liver cirrhosis and normal control, separately. The functional synergy analysis revealed prominent immune dysregulation at ACLF stage, whereas metabolic disruption was significantly down-regulated. Relative proportions of innate immune-related cells showed significant elevation of monocytes and macrophages, whereas adaptive immune-related cells were reduced. The seven differentially expressed genes underlying the ACLF molecular mechanisms were externally validated, among them THBS1, IL-10, and NR4A3 expressions were confirmed in rats, patient transcriptomics, and liver biopsies, verifying their potential value in the ACLF pathogenesis. This study indicates immune-metabolism disorder in ACLF rats, which may provide clinicians new targets for improving intervention strategies.
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Insuficiência Hepática Crônica Agudizada/etiologia , Insuficiência Hepática Crônica Agudizada/metabolismo , Suscetibilidade a Doenças , Metabolismo Energético , Imunidade , Insuficiência Hepática Crônica Agudizada/patologia , Animais , Biomarcadores , Microambiente Celular/genética , Microambiente Celular/imunologia , Modelos Animais de Doenças , Suscetibilidade a Doenças/imunologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Ratos , TranscriptomaRESUMO
BACKGROUND & AIMS: Early determination of the prognosis of patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is important to guide clinical management and decrease mortality. The aim of this study was to develop a new simplified prognostic score to accurately predict outcomes in patients with HBV-ACLF. METHODS: Prospective clinical data from 2,409 hospitalized patients with acute deterioration of HBV-related chronic liver disease were used to develop a new prognostic score that was validated in an external group. RESULTS: A total of 954 enrolled patients with HBV-ACLF were diagnosed based on the Chinese Group on the Study of Severe Hepatitis B-ACLF (COSSH-ACLF) criteria. Six predictive factors were significantly related to 28-day mortality and constituted a new prognostic score (=1.649×ln(international normalized ratio)+0.457×hepatic encephalopathy score+0.425×ln(neutrophil)+0.396×ln(total bilirubin)+0.576×ln(serum urea)+0.033×age). The C-indices of the new score for 28-/90-day mortality (0.826/0.809) were significantly higher than those of 4 other scores (COSSH-ACLF, 0.793/0.784; CLIF-C ACLF, 0.792/0.770; MELD, 0.731/0.727; MELD-Na, 0.730/0.726; all p <0.05). The prediction error rates of the new score for 28-day mortality were significantly lower than those of the 4 other scores: COSSH-ACLF (15.9%), CLIF-C ACLF (16.3%), MELD (35.3%) and MELD-Na (35.6%). The probability density function evaluation and risk stratification of the new score also showed the highest predictive values for mortality. These results were then validated in an external cohort. CONCLUSION: A new prognostic score based on 6 predictors, without an assessment of organ failure, can accurately predict short-term mortality in patients with HBV-ACLF and might be used to guide clinical management. LAY SUMMARY: Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a complex syndrome that is associated with a high short-term mortality rate. We developed a simplified prognostic score for patients suffering from this condition based on a prospective multicentre cohort. This new score had better predictive ability than 4 other commonly used scores.
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Hepatite B/classificação , Hepatite B/diagnóstico , Projetos de Pesquisa/normas , Insuficiência Hepática Crônica Agudizada/epidemiologia , Insuficiência Hepática Crônica Agudizada/etiologia , Adulto , Estudos de Coortes , Feminino , Hepatite B/complicações , Vírus da Hepatite B/metabolismo , Vírus da Hepatite B/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Curva ROC , Projetos de Pesquisa/estatística & dados numéricos , Estudos Retrospectivos , Estatísticas não ParamétricasRESUMO
Ulcerative colitis (UC) is a chronic and relapsing inflammatory bowel disorder in the colon and rectum leading to low life-quality and high societal costs. Ursolic acid (UA) is a natural product with pharmacological and biological activities. The studies are aimed at investigating the protective and treatment effects of UA against the dextran sulfate sodium- (DSS-) induced UC mouse model and its underlying mechanism. UA was orally administered at different time points before and after the DSS-induced model. Mice body weight, colon length, and histological analysis were used to evaluate colon tissue damage and therapeutic evaluation. Intestinal transcriptome and microbe 16 s sequencing was used to analyze the mechanisms of UA in the prevention and treatment of UC. The early prevention effect of UA could effectively delay mouse weight loss and colon length shorten. UA alleviated UC inflammation and lowered serum and colon IL-6 levels. Three classical inflammatory pathways: MAPKs, IL-6/STAT3, and PI3K were downregulated by UA treatment. The proportion of macrophages and neutrophils in inflammatory cell infiltration was reduced in UA treatment groups. UA could significantly reduce the richness of intestinal flora to avoid the inflammatory response due to the destruction of the intestinal epithelial barrier. The function of UA against UC was through reducing intestinal flora abundance and regulating inflammatory and fatty acid metabolism signaling pathways to affect immune cell infiltration and cytokine expression.
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Colite Ulcerativa/prevenção & controle , Microbioma Gastrointestinal/efeitos dos fármacos , Triterpenos/administração & dosagem , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/imunologia , Colite Ulcerativa/microbiologia , Colo/efeitos dos fármacos , Colo/imunologia , Colo/microbiologia , Colo/patologia , Citocinas/metabolismo , Sulfato de Dextrana/administração & dosagem , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Microbioma Gastrointestinal/imunologia , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Masculino , Camundongos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Ácido UrsólicoRESUMO
AIM: The artificial liver support system (ALSS) is recognized as a bridge to liver transplantation in hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) patients. However, patient survival remains unknown. We aim to assess the effects of ALSS on survival in HBV-ACLF patients. METHODS: The clinical data of HBV-ACLF patients receiving standard medical treatment (SMT) plus ALSS (ALSS group, n = 507) or only SMT (SMT group, n = 417) were collected for survival assessment. The main end-points were cumulative survival rates at days 21, 28, and 90. Four different rigorous analyses were carried out to reduce bias and confounding. RESULTS: In the entire cohort, the cumulative survival rates at days 21, 28, and 90 were significantly higher in patients who underwent ALSS treatment (73.3% vs. 59.6%, 69.2% vs. 56.6%, 56.5% vs. 49.1%, respectively, P < 0.01) than in those who underwent SMT only. In the 276-pair case-control matched cohort, a significantly higher survival rate was also observed in the ALSS group than in the SMT group on days 21, 28, and 90 (72.5% vs. 60.3%, 68.3% vs. 57.4%, 55.9% vs. 48.5%, respectively, P < 0.05), especially in patients with ACLF-1 and -2. By a multivariable-adjusted analysis, ALSS treatment was associated with a significantly lower risk of mortality, especially for ACLF-2 at days 21, 28, and 90. These findings were also confirmed through propensity score matching and inverse probability treatment weighting analysis. CONCLUSIONS: ALSS treatment can improve short-term survival and is associated with a significantly lower risk of short-term mortality in patients with HBV-ACLF, especially ACLF-2.
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Background: Human bone marrow mesenchymal stem cell-derived hepatocyte-like cells (hBMSC-HLCs) are a promising alternative for primary human hepatocytes (HHs) for treating liver disease. However, the molecular characteristics of HLCs remain unclear. Here, we aimed to clarify the transcriptome characteristics of hBMSC-HLCs for future clinical application. Materials and Methods: hBMSCs were isolated from the bone marrow of healthy volunteers and differentiated into hepatocytes. mRNA sequencing was used in the transcriptome profiling of hBMSC-HLCs, with hBMSCs and HHs as controls. Results: hBMSC-HLCs exhibited a polygonal morphology, glycogen accumulation and albumin expression. A total of 630 upregulated and 1082 downregulated genes were observed in hBMSC-HLCs and HHs compared with undifferentiated hBMSCs. The upregulated genes were mainly involved in hepatic metabolism and inflammatory and immune responses. The downregulated genes were mainly associated with stem cell characteristics (multipotent differentiation, cell cycle regulation, etc.). Confirmatory qRT-PCR of 9 upregulated and 9 downregulated genes with log2 fold changes > 5 showed similar results. In vivo transdifferentiation of hBMSCs in pigs with fulminant hepatic failure confirmed the similarly upregulated expression of 5 hepatogenic genes (TDO2, HP, SERPINA3, LBP and SAA1), showing a 150-fold change in liver tissues at 7 days after hBMSC transplantation. These 5 genes mainly contributed to liver metabolism and inflammation. Conclusion: hBMSC-HLCs possess a hepatic transcriptome profile and express hepatic-specific genes in vitro and in vivo, which might be useful for future clinical applications. The five upregulated genes identified herein could be potential biomarkers for the characterization of hBMSC-HLCs.
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Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Perfilação da Expressão Gênica/métodos , Hepatócitos/citologia , Hepatócitos/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Biomarcadores/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Humanos , RNA Mensageiro/metabolismoRESUMO
A novel and regioselective umpolung synthesis of spirooxindoles has been developed by cooperative NHC-Lewis acid-mediated formal [3 + 2] annulations of alkynyl aldehydes with isatins. In most cases, the reactions proceeded via a(3)-d(3) umpolung of alkynyl aldehydes resulting in spirooxindole butenolides. In a few cases, spirooxindole furan-3(2H)-ones were formed as the major products via an a(1)-d(1) umpolung process by controlling the reaction temperature. These newly formed spirooxindoles could provide promising candidates for chemical biology and drug lead discovery.
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Ácidos Heterocíclicos/química , Aldeídos/química , Alcinos/química , Química Orgânica/métodos , Isatina/química , Ácidos de Lewis/química , Metano/análogos & derivados , Catálise , Cristalografia por Raios X , Metano/química , EstereoisomerismoRESUMO
A new and stereoselective synthetic approach to spirooxindole 4H-pran-2-one derivatives with three contiguous stereogenic centers has been developed via an NHC-catalyzed three-component domino reaction of alkynyl aldehydes with oxindoles. The reaction proceeds smoothly in good yields with good to high diastereoselectivities. These novel heterocyclic spirooxindoles may provide promising candidates for drug discovery. Additionally, a possible mechanism for the entire reaction sequence is proposed.
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Aldeídos/química , Compostos Heterocíclicos/química , Indóis/química , Metano/análogos & derivados , Catálise , Hidrogenação , Metano/química , Estrutura Molecular , Oxindóis , Compostos de Espiro/química , EstereoisomerismoRESUMO
The transplantation of hepatic progenitor cells (HPCs) is a promising alternate approach to liver transplantation for patients with end-stage liver disease. Here, we report a novel technique for HPCs isolation from normal adult rat livers (no preexposure to chemicals and no injury). HPCs were isolated from normal adult rat livers using a novel four-step collagenase perfusion method followed by density gradient centrifugation. The phenotypic properties of HPCs were characterized by morphological observation, reverse-transcription polymerase chain reaction (RT-PCR), and immunocytochemistry. The results showed that HPCs formed loose colonies and possessed a round or oval shape at culture day 3. These cells proliferated slowly and exhibited progenitor-like characteristics during the 30-day culture period. RT-PCR analysis indicated that the cultured cells were positive for several HPC-specific genes, such as albumin (ALB), alpha-fetoprotein (AFP), cytokeratin 18 (CK18), cytokeratin 19 (CK19), CD45, hepatocyte nuclear factor 1-alpha (HNF-1α), hepatocyte nuclear factor 4-alpha (HNF-4α), and Thy-1. Immunocytochemical staining showed that these cells were consistently positive for ALB, AFP, CK18, CK19, Thy-1, and OV-6. HPCs can be isolated from normal adult rat livers using a simple and effective technique involving four-step collagenase perfusion, further confirming their potential as a strong candidate for hepatocyte therapy.
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Técnicas de Cultura de Células/métodos , Hepatócitos/citologia , Fígado/patologia , Células-Tronco/citologia , Animais , Biotinilação , Proliferação de Células , Terapia Baseada em Transplante de Células e Tecidos/métodos , Centrifugação com Gradiente de Concentração/métodos , Imuno-Histoquímica/métodos , Masculino , Fenótipo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodosRESUMO
Acute and chronic hepatic failure is a devastating illness of varied causes with considerable mortality. Human augmenter of liver regeneration (hALR) is a hepatotrophic protein and the unique cytokine which can specially stimulate hepatic origin cells to grow regardless of genus. It has been proven that ALR can promote regeneration and avoid all kinds of injury in rat and canine models. In this study, the recombinant protein hALR was expressed successfully with recombinant prokaryotic expression vector pET28a(+) in Escherichia coli BL21 (DE3). We constructed the recombinant expression vector pET28a(+)/hALR with a full-length cDNA encoding hALR protein from normal human liver tissue by one-step reverse transcription-polymerase chain reaction and his-tag recognition sequence encoding polyhistidine (6 x His). Under IPTG (isopropyl-beta-d-thiogalactopyranoside) induction for 2 h at 37 degrees C, recombinant protein hALR was expressed. The expression of recombinant polyhistidine-tagged hALR was increased under low temperature and was confirmed that the temperature of 23 degrees C was the most suitable IPTG induction condition. Under low temperature induction of IPTG, recombinant protein can be expressed as a soluble protein. Recombinant protein hALR was also purified with His Bind Kits and characterized with SDS-PAGE and Western blotting. The results showed that recombinant hALR could be expressed as a soluble protein under low temperature induction of IPTG. The successful expression of ALR in E. coli makes it possible to further study its biological function and purified recombinant hALR could be developed into a new anti-hepatic damage product.