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1.
Org Lett ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995695

RESUMO

A metal-free cascade of α-acyloxylation/carboxamidation of I(III)/S(VI)-ylides, carboxylic acids, and isonitriles via a Passerini-like multicomponent reaction is reported. Unexpectedly, [3 + 1+1] cyclization involving I(III)/S(VI)-ylides and two molecules of ethyl isocyanoacetate was observed. The strategy allows for the synthesis of unsymmetrical α,α-disubstituted ketones and functionalized pyrroles with up to 99% yield and wide substrate compatibility. Notably, the procedure has been extended to the late-stage modification of drugs and natural products, offering an elegant complement to the classic Passerini reaction.

2.
Org Lett ; 26(27): 5811-5816, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38940397

RESUMO

A practical strategy for the construction of diverse phosphonyl and thiofunctionalized sulfoxonium ylides via controllable monofunctionalization of hybrid I(III)/S(VI) ylides is presented. This process allows efficient P-H insertion of I(III)/S(VI) ylides under Cu catalysis, enabling the synthesis of phosphonyl sulfoxonium ylides, whereas reaction with sulfur-containing reagents including AgSCF3, KSC(S)OR, and KSCN under mild conditions resulted in α-trifluoromethylthiolation, dithiocarbanation, and thiocyanation of sulfoxonium ylides accordingly. Of note, wide substrate compatibility (108 examples), excellent efficiency (up to 99% yield), gram-scale experiments, and various product derivatizations highlight the synthetic utility of this protocol.

3.
Chin J Integr Med ; 30(2): 143-151, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37046128

RESUMO

OBJECTIVE: To evaluate if berberine can act on vitamin D receptors (VDR) and thereby regulate the expression of tight junction proteins (TJPs) in irritable bowel syndrame-diarrhea-predominant (IBS-D) rats. METHODS: The newborn rats were induced into IBS-D rat model via neonatal maternal separation combined with acetic acid chemical stimulation. After modeling, the model was evaluated and rats were divided into the control group and berberine treatment groups (0.85, 1.7 and 3.4 mg/kg, once a day for 2 weeks). The distal colon was obtained and colonic epithelial cells (CECs) were isolated and cultured after IBS-D model evaluation. The vitamin D receptor response element (VDRE) reporter gene was determined in the CECs of IBS-D rats to analyze the effect of berberine on the VDRE promoter. VDR overexpression or silencing technology was used to analyze whether VDR plays a role in promoting intestinal barrier repair, and to determine which region of VDR plays a role in berberine-regulated intestinal TJPs. RESULTS: The IBS-D rat model was successfully constructed and the symptoms were improved by berberine in a dose-dependent manner (P<0.05). The activity of VDRE promoter was also effectively promoted by berberine (P<0.05). Berberine increased the expression of TJPs in IBS-D CECs (P<0.05). VDR expression was significantly increased after transfection of different domains of VDR when compared to normal control and basic plasmid groups (all P<0.05). RT-qPCR and Western blot results showed that compared with the blank group, expressions of occludin and zonula occludens-1 were significantly higher in VDR containing groups (all P<0.05). Berberine plus pCMV-Myc-VDR-N group exerted the highest expression levels of occludin and zonula occludens-1 (P<0.05). CONCLUSION: Berberine enhances intestinal mucosal barrier function of IBS-D rats by promoting VDR activity, and the main site of action is the N-terminal region of VDR.


Assuntos
Berberina , Síndrome do Intestino Irritável , Ratos , Animais , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Berberina/farmacologia , Berberina/uso terapêutico , Função da Barreira Intestinal , Ocludina/genética , Ocludina/metabolismo , Privação Materna , Diarreia , Mucosa Intestinal
4.
Org Lett ; 25(28): 5179-5184, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37415264

RESUMO

Rh (III)-catalyzed dienylation and cyclopropylation of 1,2,3-benzotriazinones with alkylidenecyclopropanes (ACPs) has been achieved. Different from the previous reports of 1,2,3-benzotriazinones, the triazinone ring remained intact in this C-H bond functionlization reaction. Also, the denitrogenative cyclopropylation could also be realized by changing the reaction temperature. This protocol is featured with high E selectivity, wide substrate scope, and divergent structures of products.

5.
Org Lett ; 25(23): 4286-4291, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37265108

RESUMO

Two categories of tetrasubstituted phenols were prepared via the cycloaddition reaction of vinyl sulfoxonnium ylides with cyclopropenones in a switchable manner. Copper carbenoid was proposed as the active intermediate in the process of 2,3,4,5-tetrasubstituted phenols formation, while 2,3,5,6-tetrasubstituted phenols were generated via the direct [3 + 3] annulation of vinyl sulfoxonnium ylides with cyclopropenones under metal-free conditions. Further synthetic applications were also demonstrated.


Assuntos
Cobre , Metais , Catálise , Reação de Cicloadição
6.
J Viral Hepat ; 29(5): 317-329, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35253969

RESUMO

The study aimed to investigate the prevalence and risk factors associated with occult hepatitis B virus (HBV) infection (OBI) in the global population. We searched PubMed, Embase, CINAHL, Cochrane and Web of Science from database inception through 27 Dec, 2018. Studies reporting HBV-DNA serological data in previously undiagnosed hepatitis B patients were included. The data were further categorized according to the presence of risk factors. After an initial screening of 2,325 records, we finally included 98 articles about the prevalence of OBI from 34 countries and regions. The OBI prevalence was 0.82% (95% CI:0.69-0.96) in the general population, 16.26% (95% CI:10.97-22.34) in HIV patients, 13.99% (95% CI:8.33-20.79) in patients with other liver diseases, 4.25% (95% CI:1.64-7.87) in haemodialysis patients and 5.14% (95% CI:2.26-9.01) patients with other risk factors. In conclusion, OBI prevalence varies significantly across different populations and nations, which deserve attention from the public health authorities. Our results generate further epidemiological data to identify the population with OBI, which has important clinical implications in finding these high-risk populations to design preventive and management strategies.


Assuntos
Infecções por HIV , Hepatite B Crônica , Hepatite B , DNA Viral , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B , Hepatite B Crônica/epidemiologia , Humanos , Prevalência
7.
J Viral Hepat ; 28(7): 1057-1067, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33877742

RESUMO

Hepatitis delta virus (HDV) is an obligate satellite of hepatitis B virus (HBV). HIV/HDV co-infection is associated with a high rate of hepatic decompensation events and death. We aimed to characterize the epidemiology of HDV infection in HIV/HBV co-infected individuals. We systematically searched PubMed, Embase, Cochrane Library, Web of Science, CINAHL and Scopus for studies published from 1 Jan 2002 to 7 May 2018 measuring prevalence of HDV among the HIV population. Pooled seroprevalence was calculated with the DerSimonian-Laird random-effects model. Our search returned 4624 records, 38 of which met the inclusion and exclusion criteria. These studies included data for 63 cohorts from 18 countries and regions. The overall HDV seroprevalence of HIV-infected individuals was 1.03% (95% CI 0.43-1.85) in 2002-2018 globally. Moreover, the estimated pooled HDV seroprevalence among the general population was 1.07% (95% CI 0.65-1.59) in 2002-2018, which was not significantly different from the HDV seroprevalence of individuals living with HIV (p = 0.951). The overall HDV seroprevalence of the HBsAg positive population was 12.15% (95% CI 10.22-14.20), p = 0.434 when compared with the corresponding data of HIV/HBV co-infected individuals. This meta-analysis suggested that there was no difference between the HDV seroprevalence in HIV-infected individuals and the general population.


Assuntos
Coinfecção , Infecções por HIV , Hepatite B , Hepatite D , Coinfecção/epidemiologia , HIV , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Hepatite B/complicações , Hepatite B/epidemiologia , Vírus da Hepatite B , Hepatite D/complicações , Hepatite D/epidemiologia , Vírus Delta da Hepatite , Humanos , Prevalência , Estudos Soroepidemiológicos
8.
Orphanet J Rare Dis ; 15(1): 71, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-32164748

RESUMO

BACKGROUND: Hemophagocytic Lymphohistiocytosis (HLH) is a rare clinical syndrome with high mortality rate. The diagnosis of HLH draws on a constellation of clinical and laboratory abnormalities including extremely high serum ferritin levels. However, no biomarker has been firmly established as a clinically useful prognostic tool in HLH patients. We aimed to perform a retrospective analysis of two independent cohorts to explore the prognostic value of discharge serum ferritin for newly diagnosed adult HLH patients who recently started treatment. The prognostic value of serum ferritin levels at discharge (will be called as post-treatment ferritin level) was initially evaluated in a "test cohort" of 161 previously untreated consecutive adult HLH patients. It was then validated in a second cohort of 68 consecutive previously untreated patients (validation cohort). RESULTS: Multivariate analysis revealed that significantly high post-treatment serum ferritin levels (>1050 µg/L) were associated with a higher risk of death and poor overall survival in the test cohort (hazard ratio (HR): 3.176, 95% confidence interval (CI) 1.468-6.869, P = 0.003), and the validation cohort (HR: 13.412, 95%CI 1.716-104.816, P = 0.013). At 6-month follow-up period in the test cohort, patients with a > 81% decrease in the serum ferritin level had a significantly higher probability of survival when compared with the patients with ≥14% increase in the serum ferritin level (94% vs. 31%, P < 0.001). Similar findings were observed on the analysis of the decrease in the serum ferritin level in the validation cohort. CONCLUSIONS: These results suggest that the serum ferritin level can be used as an independent prognostic marker in the adult HLH patients.


Assuntos
Linfo-Histiocitose Hemofagocítica , Adulto , Biomarcadores , Ferritinas , Humanos , Prognóstico , Estudos Retrospectivos
11.
Gut ; 68(3): 512-521, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30228220

RESUMO

OBJECTIVE: Hepatitis D virus (HDV) is a defective virus that completes its life cycle only with hepatitis B virus (HBV). The HBV with HDV super-infection has been considered as one of the most severe forms of the chronic viral hepatitis. However, there is a scarcity of data on the global burden of HDV infection. DESIGN: We searched PubMed, Embase, Cochrane Library and China Knowledge Resource Integrated databases from 1 January 1977 to 31 December 2016. We included studies with a minimum sample size of 50 patients. Our study analysed data from a total of 40 million individuals to estimate the prevalence of HDV by using Der-Simonian Laird random-effects model. The data were further categorised according to risk factors. RESULTS: From a total of 2717 initially identified studies, only 182 articles from 61 countries and regions met the final inclusion criteria. The overall prevalence of HDV was 0.98% (95% CI 0.61 to 1.42). In HBsAg-positive population, HDV pooled prevalence was 14.57% (95% CI 12.93 to 16.27): Seroprevalence was 10.58% (95% CI 9.14 to 12.11) in mixed population without risk factors of intravenous drug use (IVDU) and high-risk sexual behaviour (HRSB). It was 37.57% (95% CI 29.30 to 46.20) in the IVDU population and 17.01% (95% CI 10.69 to 24.34) in HRSB population. CONCLUSION: We found that approximately 10.58% HBsAg carriers (without IVDU and HRSB) were coinfected with HDV, which is twofold of what has been estimated before. We also noted a substantially higher HDV prevalence in the IVDU and HRSB population. Our study highlights the need for increased focus on the routine HDV screening and rigorous implementation of HBV vaccine programme.


Assuntos
Saúde Global/estatística & dados numéricos , Hepatite D/epidemiologia , Coinfecção/epidemiologia , Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/epidemiologia , Hepatite D/transmissão , Humanos , Prevalência , Fatores de Risco , Assunção de Riscos , Comportamento Sexual , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/epidemiologia
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