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1.
J Am Chem Soc ; 146(2): 1356-1363, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38170904

RESUMO

Here, we present the second generation of our bicyclic peptide library (NTB), featuring a stereodiversified structure and a simplified construction strategy. We utilized a tandem ring-opening metathesis and ring-closing metathesis reaction (ROM-RCM) to cyclize the linear peptide library in a single step, representing the first reported instance of this reaction being applied to the preparation of macrocyclic peptides. Moreover, the resulting bicyclic peptide can be easily linearized for MS/MS sequencing with a one-step deallylation process. We employed this library to screen against the E363-R378 epitope of MYC and identified several MYC-targeting bicyclic peptides. Subsequent in vitro cell studies demonstrated that one candidate, NT-B2R, effectively suppressed MYC transcription activities and cell proliferation.


Assuntos
Biblioteca de Peptídeos , Espectrometria de Massas em Tandem , Peptídeos/farmacologia , Peptídeos/química
2.
Arch Virol ; 169(2): 30, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38233704

RESUMO

We analyzed the clinical characteristics of outpatients with influenza-B-associated pneumonia during the 2021-2022 influenza season and analyzed the molecular epidemiology and evolution of influenza B virus. The presence of influenza B virus was confirmed by reverse transcription polymerase chain reaction (RT-PCR). Electronic medical records were used to collect and analyze data of outpatients. The HA and NA genes were phylogenetically analyzed using ClustalW 2.10 and MEGA 11.0. Out of 1569 outpatients who tested positive for influenza B virus, 11.7% (184/1569) developed pneumonia, and of these, 19.0% (35/184) had underlying diseases. Fever, cough, and sore throat were the most common symptoms. Among the complications, acute respiratory distress syndrome (ARDS), acute kidney injury (AKI), and shock accounted for 2.7% (5/184), 4.9% (9/184), and 1.6% (3/184), respectively. Of the outpatients, 2.7% (5/184) were admitted to the hospital, and 0.5% (1/184) of them died. All of the strains from Beijing were identified as belonging to the B/Victoria lineage. The HA and NA gene sequences of 41 influenza B viruses showed high similarity to each other, and all of them belonged to clade 1A.3. Compared with the vaccine strain B/Washington/02/2019, all of the isolates contained N150K, G181E, and S194D mutations. S194D, E195K, and K200R mutations were detected in the 190 helix of the receptor binding region of HA. Co-mutations of H122Q, A127T, P144L, N150K, G181E, S194D, and K200R in HA and D53N, N59S, and G233E in NA were detected in 78.0% (32/41) of the isolates, and 56.3% (18/32) of these were from outpatients with influenza-B-associated pneumonia. Influenza outpatients with underlying diseases were more likely to develop pneumonia. No significant differences were observed in clinical symptoms or laboratory results between outpatients with and without pneumonia, so testing for influenza virus seems to be a good choice. The observed amino acid variations suggest that current vaccines might not provide effective protection.


Assuntos
Influenza Humana , Humanos , Influenza Humana/epidemiologia , Vírus da Influenza B , Pequim , Estações do Ano , Pacientes Ambulatoriais , Evolução Molecular , Filogenia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética
3.
Virol J ; 20(1): 101, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37237356

RESUMO

BACKGROUND: Influenza A viruses have undergone rapid evolution with virulent; however, complete and comprehensive data on gene evolution and amino acid variation of HA and NA in immunosuppressed patients was few. In this study, we analysed molecular epidemiology and evolution of influenza A viruses in immunosuppressed population, and immunocompetent population were used as controls. METHODS: Full sequences of HA and NA of A(H1N1)pdm09 and A(H3N2) were acquired through reverse transcription-polymerase chain reaction (RT-PCR). HA and NA genes were sequenced using the Sanger method and phylogenetically analysed using ClustalW 2.10 and MEGA software version 11.0. RESULTS: During the 2018-2020 influenza seasons, 54 immunosuppressed and 46 immunocompetent inpatients screened positive for influenza A viruses by using the quantitative real-time PCR (qRT-PCR) were enrolled. 27 immunosuppressed and 23 immunocompetent nasal swab or bronchoalveolar lavage fluid samples were randomly selected and sequenced using the Sanger method. A(H1N1)pdm09 were detected in 15 samples and the remaining 35 samples were A(H3N2) positive. By analyzing the HA and NA gene sequences of these virus strains, we found that all A(H1N1)pdm09 viruses shared high similarities to each other and the HA and NA genes of these viruses exclusively belonged to subclade 6B.1A.1. Some NA genes of A(H3N2) viruses were not in the same clade as those of A/Singapore/INFIMH-16-0019/2016 and A/Kansas/14/2017, which may have led to A(H3N2) being the dominant strain in the 2019-2020 influenza season. Both A(H1N1)pdm09 and A(H3N2) viruses showed similar evolutionary lineages patterns of HA and NA between immunosuppressed and immunocompetent patients. Compared with the vaccine strains, there were no statistically significant of HA and NA genes and amino acid sequences of influenza A viruses in immunosuppressed and immunocompetent patients. However, the oseltamivir resistance substitution of NA-H275Y and R292K have been observed in immunosuppressed patients. CONCLUSIONS: A(H1N1)pdm09 and A(H3N2) viruses showed similar evolutionary lineages patterns of HA and NA between immunosuppressed and immunocompetent patients. Both immunocompetent and immunosuppressed patients have some key substitutions, which should be of note monitored, especially those with potential to affect the viral antigen.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A , Influenza Humana , Humanos , Vírus da Influenza A/genética , Influenza Humana/epidemiologia , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/genética , Filogenia , Estações do Ano , Pacientes Internados , Pequim , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Neuraminidase/genética
4.
BMC Pregnancy Childbirth ; 23(1): 76, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36709255

RESUMO

BACKGROUND: This systematic review aims to explore the prevalence of the impact of the COVID-19, MERS, and SARS pandemics on the mental health of pregnant women. METHODS: All COVID-19, SARS and MERS studies that evaluated the mental health of pregnant women with/without gynaecological conditions that were reported in English between December 2000 - July 2021 were included. The search criteria were developed based upon the research question using PubMed, Science Direct, Ovid PsycINFO and EMBASE databases. A wide search criterion was used to ensure the inclusion of all pregnant women with existing gynaecological conditions. The Newcastle-Ottawa-Scale was used to assess the risk of bias for all included studies. Random effects model with restricted maximum-likelihood estimation method was applied for the meta-analysis and I-square statistic was used to evaluate heterogeneity across studies. The pooled prevalence rates of symptoms of anxiety, depression, PTSD, stress, and sleep disorders with 95% confidence interval (CI) were computed. RESULTS: This systematic review identified 217 studies which included 638,889 pregnant women or women who had just given birth. There were no studies reporting the mental health impact due to MERS and SARS. Results showed that women who were pregnant or had just given birth displayed various symptoms of poor mental health including those relating to depression (24.9%), anxiety (32.8%), stress (29.44%), Post Traumatic Stress Disorder (PTSD) (27.93%), and sleep disorders (24.38%) during the COVID-19 pandemic. DISCUSSION: It is important to note that studies included in this review used a range of outcome measures which does not allow for direct comparisons between findings. Most studies reported self-reported measure of symptoms without clinical diagnoses so conclusions can be made for symptom prevalence rather than of mental illness. The importance of managing mental health during pregnancy and after-delivery improves the quality of life and wellbeing of mothers hence developing an evidence-based approached as part of pandemic preparedness would improve mental health during challenging times. OTHER: The work presented in this manuscript was not funded by any specific grants. A study protocol was developed and published in PROSPERO (CRD42021235356) to explore several key objectives.


Assuntos
COVID-19 , Transtornos do Sono-Vigília , Feminino , Gravidez , Humanos , Saúde Mental , Pandemias , COVID-19/epidemiologia , Prevalência , Qualidade de Vida , Parto , Ansiedade/epidemiologia , Transtornos do Sono-Vigília/epidemiologia , Depressão/epidemiologia
5.
Zhongguo Zhong Yao Za Zhi ; 48(24): 6702-6710, 2023 Dec.
Artigo em Zh | MEDLINE | ID: mdl-38212030

RESUMO

This study aims to explore the influence of Polygonati Rhizoma on the pyroptosis in the rat model of diabetic macroangiopathy via the NOD-like receptor thermal protein domain associated protein 3(NLRP3)/cysteinyl aspartate specific proteinase-1(caspase-1)/gasdermin D(GSDMD) pathway. The rat model of diabetes was established by intraperitoneal injection of streptozotocin(STZ) combined with a high-fat, high-sugar diet. The blood glucose meter, fully automated biochemical analyzer, hematoxylin-eosin(HE) staining, enzyme-linked immunosorbent assay, immunofluorescence, immunohistochemistry, and Western blot were employed to measure blood glucose levels, lipid levels, vascular thickness, inflammatory cytokine levels, and expression levels of pyroptosis-related proteins. The mechanism of pharmacological interventions against the injury in the context of diabetes was thus explored. The results demonstrated the successful establishment of the model of diabetes. Compared with the control group, the model group showed elevated levels of fasting blood glucose, total cholesterol(TC), triglycerides(TG) and low-density lipoprotein cholesterol(LDL-c), lowered level of high-density lipoprotein cholesterol(HDL-c), thickened vascular intima, and elevated serum and aorta levels of tumor necrosis factor-α(TNF-α), interleukin-1ß(IL-1ß) and interleukin-18(IL-18). Moreover, the model group showed increased NLRP3 inflammasomes and up-regulated levels of caspase-1 and GSDMD in aortic vascular cells. Polygonati Rhizoma intervention reduced blood glucose and lipid levels, inhibited vascular thickening, lowered the levels of TNF-α, IL-1ß, IL-18 in the serum and aorta, attenuated NLRP3 inflammasome expression, and down-regulated the expression levels of caspase-1 and GSDMD, compared with the model group. In summary, Polygonati Rhizoma can slow down the progression of diabetic macroangiopathy by inhibiting pyroptosis and alleviating local vascular inflammation.


Assuntos
Complicações do Diabetes , Diabetes Mellitus , Doenças Vasculares , Animais , Ratos , Caspase 1/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Interleucina-18 , Glicemia , Piroptose , Fator de Necrose Tumoral alfa , Inflamassomos , Colesterol , Lipídeos
6.
J Am Chem Soc ; 144(44): 20288-20297, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36301712

RESUMO

Delivering cargo molecules across the plasma membrane is critical for biomedical research, and the need to develop molecularly well-defined tags that enable cargo transportation is ever-increasing. We report here a hydrophilic endocytosis-promoting peptide (EPP6) rich in hydroxyl groups with no positive charge. EPP6 can transport a wide array of small-molecule cargos into a diverse panel of animal cells. Mechanistic studies revealed that it entered the cells through a caveolin- and dynamin-dependent endocytosis pathway, mediated by the surface receptor fibrinogen C domain-containing protein 1. After endocytosis, EPP6 trafficked through early and late endosomes within 30 min. Over time, EPP6 partitioned among cytosol, lysosomes, and some long-lived compartments. It also demonstrated prominent transcytosis abilities in both in vitro and in vivo models. Our study proves that positive charge is not an indispensable feature for hydrophilic cell-penetrating peptides and provides a new category of molecularly well-defined delivery tags for biomedical applications.


Assuntos
Peptídeos Penetradores de Células , Endocitose , Animais , Endossomos/metabolismo , Peptídeos Penetradores de Células/metabolismo , Lisossomos/metabolismo , Interações Hidrofóbicas e Hidrofílicas
7.
Virol J ; 19(1): 11, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-35033116

RESUMO

BACKGROUND: Compared with immunocompetent patients, immunosuppressed patients have higher morbidity and mortality, a longer duration of viral shedding, more frequent complications, and more antiviral resistance during influenza infections. However, few data on this population in China have been reported. We analysed the clinical characteristics, effects of antiviral therapy, and risk factors for admission to the intensive care unit (ICU) and death in this population after influenza infections and explored the influenza vaccination situation for this population. METHODS: We analysed 111 immunosuppressed inpatients who were infected with influenza virus during the 2015-2020 influenza seasons. Medical data were collected through the electronic medical record system and analysed. Univariate analysis and multivariate logistics analysis were used to identify risk factors. RESULTS: The most common cause of immunosuppression was malignancies being treated with chemotherapy (64.0%, 71/111), followed by haematopoietic stem cell transplantation (HSCT) (23.4%, 26/111). The most common presenting symptoms were fever and cough. Dyspnoea, gastrointestinal symptoms and altered mental status were more common in HSCT patients than in patients with immunosuppression due to other causes. Approximately 14.4% (16/111) of patients were admitted to the ICU, and 9.9% (11/111) of patients died. Combined and double doses of neuraminidase inhibitors did not significantly reduce the risk of admission to the ICU or death. Risk factors for admission to the ICU were dyspnoea, coinfection with other pathogens and no antiviral treatment within 48 h. The presence of dyspnoea and altered mental status were independently associated with death. Only 2.7% (3/111) of patients less than 12 months old had received a seasonal influenza vaccine. CONCLUSION: Fever and other classic symptoms of influenza may be absent in immunosuppressed recipients, especially in HSCT patients. Conducting influenza virus detection at the first presentation seems to be a good choice for early diagnosis. Clinicians should pay extra attention to immunosuppressed patients with dyspnoea, altered mental status, coinfection with other pathogens and no antiviral treatment within 48 h because these patients have a high risk of severe illness. Inactivated influenza vaccines are recommended for immunosuppressed patients.


Assuntos
Vacinas contra Influenza , Influenza Humana , Antivirais/uso terapêutico , Pequim , Humanos , Influenza Humana/tratamento farmacológico , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Pacientes Internados , Fatores de Risco , Estações do Ano
8.
Arch Virol ; 166(1): 179-189, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33145635

RESUMO

We investigated and analysed the molecular evolution of hemagglutinin (HA) and neuraminidase (NA) of influenza A(H1N1)pdm09 virus during the 2017-2018 and 2018-2019 influenza seasons in Beijing, China. We collected and extracted RNA from influenza A(H1N1)pdm09 strains from Peking University People's Hospital and analyzed their HA and NA genes by RT-PCR and sequencing. Phylogenetic analysis of HA and NA sequences was used to compare the amino acid sequences of 51 strains with those of reference strains. All strains belonged to subclade 6B.1, with S162N and I216T substitutions (H1 numbering). Our strains differed from strain A/Michigan/45/2015, with the substitutions S91R, S181T and I312V in the HA antigenic epitope. An E189G mutation was detected in the 190 helix of the receptor binding region of HA. A new potential glycosylation site, 179 (NQT), which was not detected before the 2015 influenza season, was identified. Two strains were mutated at I223, the NA inhibitor resistance site. During 2012-2019, amino acids of HA and NA mutated over time. Co-occurrence mutations N146D, S200P, S202I and A273T in HA appeared along with Q51K, F74S and D416N in NA in six strains during two influenza seasons. Our work reveals the molecular changes and phylogenetic characteristics of influenza A(H1N1)pdm09 virus and suggests that a vaccine probably provides suboptimal protection. The biological characteristics of the new glycosylation and drug-resistance sites detected in this work need to be studied further. The co-occurrence of mutations in HA and NA might affect the characteristics of the virus and need to be given more attention.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/virologia , Neuraminidase/genética , Substituição de Aminoácidos/genética , Antígenos Virais/genética , Pequim , Evolução Molecular , Variação Genética/genética , Humanos , Filogenia , Estações do Ano , Análise de Sequência de DNA/métodos
9.
Virol J ; 17(1): 182, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33213486

RESUMO

BACKGROUND: Influenza A(H1N1)pdm09 viruses have undergone rapid evolution, and in recent years the complementary and antagonistic effects of HA and NA have gathered more attentions; however, the effects of co-occurring mutations in HA and NA on the patients' clinical characteristics are still poorly understood. In this study, we analyzed molecular epidemiology and evolution of A(H1N1) pdm09, explored co-occurring mutations of HA and NA, and investigated effect of co-occurring mutations on patients' clinical features. METHODS: A(H1N1)pdm09 was confirmed by reverse transcription-polymerase chain reaction. HA and NA genes were sequenced and phylogenetically analyzed. Clinical characteristics of the co-occurring mutations were analyzed statistically. RESULTS: By analyzing the HA and NA gene sequences of 33 A(H1N1)pdm09 viruses during the 2015-2017 influenza season, we found that all the viruses shared high similarities to each other and the HA genes of these viruses exclusively belonged to subclade 6B.1A. Several unreported substitutions in HA and NA proteins were observed, furthermore, co-occurring mutations of HA-V169T, A278S, E508G, D518E and NA-V67I were detected in 30.3% (10/33) A(H1N1)pdm09 virus strains when comparing with vaccine strains A/California/07/2009 and A/Michigan/45/2015 (H1N1). Sore throat was significantly associated with co-occurring mutations in HA and NA of A(H1N1)pdm09 (χ2, P < 0.05). CONCLUSIONS: Co-occurring mutations in HA and NA were detected in A(H1N1)pdm09 isolated during 2015-2017 in Beijing. Symptomatically, sore throat was associated with co-occurring mutations in HA and NA of A(H1N1)pdm09. Therefore, studying the effect and mechanism of co-occurring mutations in HA and NA on patients' clinical features is of note needed.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/epidemiologia , Mutação , Neuraminidase/genética , Filogenia , Adolescente , Adulto , Idoso , Substituição de Aminoácidos , Pequim/epidemiologia , Epidemias/estatística & dados numéricos , Evolução Molecular , Feminino , Variação Genética , Humanos , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , RNA Viral/genética , Análise de Sequência de DNA , Adulto Jovem
10.
J Am Acad Dermatol ; 83(3): 824-831, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31404571

RESUMO

BACKGROUND: Graft-versus-host disease (GVHD) has various cutaneous manifestations. Little is known about the mechanisms of cutaneous GVHD with different clinical features. OBJECTIVE: To characterize the immunologic features and skin barrier functions of cutaneous GVHD. METHODS: The study included 19 patients with atopic dermatitis (AD)-like GVHD, 8 with lichen planus (LP)-like GVHD, 24 with AD, and 15 healthy controls. The subpopulation of T cells in peripheral blood and skin lesions was measured by flow cytometry and immunofluorescence, respectively. Filaggrin expression in skin lesions was measured by Western blot and immunohistochemistry. Transepidermal water loss was also measured using Tewameter TM 300 (Courage & Khazaka Electronic GmbH, Köln, Germany). RESULTS: The number of peripheral blood eosinophils in AD-like GVHD was significantly higher than that in LP-like GVHD. Type 2 helper T cells in peripheral blood and skin lesions were increased in AD-like GVHD and LP-like GVHD. Regulatory T cells in peripheral blood and skin lesions were increased in AD-like GVHD. Filaggrin expression and transepidermal water loss were increased in skin lesions of AD-like GVHD and LP-like GVHD. LIMITATIONS: The number of patients is limited. CONCLUSION: Although AD-like GVHD and LP-like GVHD both had elevated type 2 helper T cells and impaired skin barrier, increased eosinophils and regulatory T cells were found only in AD-like GVHD.


Assuntos
Dermatite Atópica/diagnóstico , Eosinófilos , Doença Enxerto-Hospedeiro/diagnóstico , Líquen Plano/diagnóstico , Linfócitos T Reguladores , Adolescente , Adulto , Estudos de Casos e Controles , Dermatite Atópica/sangue , Dermatite Atópica/imunologia , Dermatite Atópica/patologia , Diagnóstico Diferencial , Feminino , Proteínas Filagrinas , Doença Enxerto-Hospedeiro/sangue , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Voluntários Saudáveis , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Contagem de Leucócitos , Líquen Plano/sangue , Líquen Plano/imunologia , Líquen Plano/patologia , Masculino , Pele/citologia , Pele/imunologia , Pele/patologia , Transplante Homólogo/efeitos adversos , Perda Insensível de Água/imunologia , Adulto Jovem
11.
Apoptosis ; 24(1-2): 135-144, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30426280

RESUMO

We have previously identified that PPPDE1 is a deubiquitinase (DUB) belonging to a cysteine isopeptidase family. Here we sought to explore the biological significance of PPPDE1 in hepatocellular carcinoma and its underlying molecular mechanism. In the present study, we found that amplification and overexpression of PPPDE1 were associated with poor prognosis in hepatocellular carcinoma (HCC). We also demonstrated that knocking down of PPPDE1 could significantly block the clonal growth and tumorigenicity of human HCC cells, which revealed a critical role for PPPDE1 in HCC development. Furthermore, we proved that PPPDE1 is a key modulator of p53 protein level and its down stream apoptosis pathway. Taken together, these results suggested that PPPDE1 is a putative HCC driver gene and extensive studies should be conducted in the future to investigate the role of PPPDE1 in HCC and other tumors.


Assuntos
Apoptose/genética , Carbono-Nitrogênio Liases/fisiologia , Carcinoma Hepatocelular/patologia , Proliferação de Células/genética , Neoplasias Hepáticas/patologia , Proteína Supressora de Tumor p53/genética , Animais , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Estudos de Coortes , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Cell Immunol ; 337: 33-41, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30770094

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is characterized by altered intestinal microbiota and intestinal immune disorder. Here we investigated the role of mesenteric lymph node (MLN) CD4+ T lymphocytes in NAFLD. In high fat diet (HFD)-fed mice, the percentage ratios of Th1 to Th2 cells and Th17 to Treg cells were imbalanced in MLNs. Co-culture assays showed MLN CD4+ T lymphocytes from HFD-fed mice tended to migrate to the liver and promoted hepatic inflammation. Adoptive transfer of MLN CD4+ T lymphocytes from NAFLD mice to HFD-fed mice resulted in higher transaminase, worse hepatic inflammation and lipid accumulation. Antibiotics and probiotics were administrated to regulate intestinal microbiota, and the restoration of MLN Th1/Th2 and Th17/Treg cells in alleviated NAFLD were found. In summary, MLNs CD4+ T subtype cells may involve in NAFLD, and the restoration of MLN CD4+ T subtype cells ratio by regulating intestinal bacteria could be the new strategies.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Mesentério/imunologia , Hepatopatia Gordurosa não Alcoólica/imunologia , Animais , Movimento Celular/imunologia , Citocinas , Dieta Hiperlipídica , Inflamação/patologia , Fígado/imunologia , Linfonodos/imunologia , Contagem de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doenças Peritoneais/imunologia , Linfócitos T Auxiliares-Indutores/imunologia
13.
Am J Physiol Gastrointest Liver Physiol ; 315(5): G659-G670, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29902065

RESUMO

Visceral adipose tissue (VAT) is related to nonalcoholic fatty liver disease (NAFLD). However, the role of mesenteric adipose tissue (MAT), part of the VAT, in NAFLD is unclear. In the present study, we monitored the liver and four depots of the VAT in high-fat diet (HFD)-feeding mice at multiple time points (4, 8, and 12 wk). The MAT had become inflamed by the eighth week of HFD feeding, earlier than other depots of VAT. Furthermore, MAT removal after 8 wk of HFD resulted in more severe steatosis and more foci of inflammation infiltration, as well as higher NAFLD activity scores. Consistent with these findings, the mRNA expression of proinflammatory cytokines and lipid anabolism genes was increased in the livers of inflamed MAT-removal mice. MAT removal also injured the intestinal barrier and promoted intestinal inflammation. The bacterial load translocated to the liver and circulating levels of lipopolysaccharide were also evaluated in inflamed MAT-removal mice. In a coculture experiment involving adipocytes and intestinal epithelial cells, mRNA expression of zonula occludens-1 (ZO-1), and occludin in CT-26 cells was upregulated and permeability of monolayer Caco-2 cells was elevated under stimulation from adipocytes or inflamed adipocytes. Taken together, these results demonstrated that MAT removal damaged the intestinal barrier and aggravated NAFLD and that MAT inflammation may be a compensatory response to protect the liver by maintaining the intestinal barrier. NEW & NOTEWORTHY The mesenteric adipose tissue (MAT) lies between the gut and liver and plays a critical role in hepatic metabolic diseases. In the present study, we found that the MAT was prone to inflammation in high-fat diet-fed mice. Removal of the inflamed MAT resulted in more hepatic inflammation, lipid accumulation, and decreased glucose tolerance. Furthermore, we showed that the MAT contributed to intestinal barrier integrity, thus clarifying why MAT removal aggravated nonalcoholic fatty liver disease.


Assuntos
Adipócitos/metabolismo , Mucosa Intestinal/metabolismo , Gordura Intra-Abdominal/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Células 3T3 , Animais , Células CACO-2 , Células Cultivadas , Citocinas/metabolismo , Dieta Hiperlipídica , Humanos , Inflamação/metabolismo , Gordura Intra-Abdominal/citologia , Metabolismo dos Lipídeos , Masculino , Mesentério , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Ocludina/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo
14.
Hepatobiliary Pancreat Dis Int ; 17(3): 233-240, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29625837

RESUMO

BACKGROUND: Higher hepatitis B surface antigen (HBsAg) facilitates hepatitis C virus (HCV) clearance in patients with hepatitis B virus (HBV)/HCV co-infection. We investigated the effect of exogenous HBsAg on the inhibition of HCV replication mediated by natural killer (NK) cells. METHODS: After isolated from peripheral blood of 42 chronic hepatitis B (CHB) patients and 16 healthy individuals, NK cells were co-cultured with HCV-infected Huh7 cells, respectively, with or without HBsAg. Three days later, the co-cultured supernatants were collected and HCV RNA levels were measured by real-time quantitative PCR. NKG2D, NKp46 and NKG2A expression levels were measured by flow cytometry. NKG2D on NK cells from CHB responsive subgroup was blocked and HCV RNA levels were examined again. RESULTS: HCV RNA levels in the co-cultured system were significantly reduced by NK cells isolated from healthy donors (P < 0.01) but not from CHB patients. However, HCV RNA levels in CHB cultures were significantly decreased following HBsAg addition (P < 0.05), whereas no such effect was seen in control cultures. No significant difference was observed in basic NKG2D expression between the CHB patients and healthy donors. On NK cells from CHB patients, the expression of NKG2D was increased significantly by HBsAg stimulation (P < 0.01), and higher than that from healthy controls (P < 0.05). HCV RNA levels were increased significantly after the blockage of NKG2D on NK cells from responsive CHB patients in the co-cultured system (P < 0.05). CONCLUSION: Exogenous HBsAg stimulated NKG2D expression on NK cells from CHB patients which inhibit HCV replication, suggesting that HBsAg may facilitate the clearance of HCV in patients with HBV/HCV co-infection.


Assuntos
Coinfecção , Hepacivirus/metabolismo , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B/metabolismo , Hepatite B Crônica/metabolismo , Hepatite C/metabolismo , Células Matadoras Naturais/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/imunologia , Replicação Viral , Adulto , Estudos de Casos e Controles , Linhagem Celular Tumoral , Técnicas de Cocultura , Feminino , Hepacivirus/genética , Hepacivirus/imunologia , Hepacivirus/patogenicidade , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Hepatite C/imunologia , Hepatite C/virologia , Interações Hospedeiro-Patógeno , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/virologia , Masculino , Pessoa de Meia-Idade , Subfamília C de Receptores Semelhantes a Lectina de Células NK/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptor 1 Desencadeador da Citotoxicidade Natural/metabolismo , RNA Viral/biossíntese , RNA Viral/genética , Transdução de Sinais , Carga Viral , Adulto Jovem
15.
Biochem Biophys Res Commun ; 488(2): 291-296, 2017 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-28483520

RESUMO

Ubiquitinlation of proteins is prevalent and important in both normal and pathological cellular processes. Deubiquitinating enzymes (DUBs) can remove the ubiquitin tags on substrate proteins and dynamically regulate the ubiquitination process. The PPPDE family proteins were predicted to be a novel class of deubiquitinating peptidase, but this has not yet been experimentally proved. Here we validated the deubiquitinating activity of PPPDE1 and revealed its isopeptidase activity against ubiquitin conjugated through Lys 48 and Lys 63. We also identified ribosomal protein S7, RPS7, as a substrate protein of PPPDE1. Moreover, PPPDE1 could mediate the ubiquitin chain editing of RPS7, deubiquitinating Lys 48-linked ubiquitination, and finally stabilize RPS7 proteins. Taken together, we report that PPPDE1 is a novel deubiquitinase that belongs to a cysteine isopeptidase family.


Assuntos
Carbono-Nitrogênio Liases/classificação , Carbono-Nitrogênio Liases/metabolismo , Linhagem Celular Tumoral , Humanos
16.
Yao Xue Xue Bao ; 52(2): 222-8, 2017 Feb.
Artigo em Zh | MEDLINE | ID: mdl-29979503

RESUMO

Abelmoschus manihot (L.) Medic., a folk herbal medicine in China, is a flowering plant belonging to Abelmoschus L. genus and Malvaceae family, which has been reported with an antidepressant activity. The study was designed to isolate flavonoids from Abelmoschus manihot corolla and explore the action mechanism of antidepressant activities. The flavonoids were isolated and purified by D101 macroporous resin column, polyamide column and Sephadex LH-20 sequentially and identified as myricetin-3-O-ß-D-glucoside (1), gossypetin-8-O-ß-D-glucuronide (2, G-8-G), gossypetin-3'-O-ß-D-glucoside (3), quercetin-3'-glucoside (4, Q-3-G), isoquercitrin (5, IQT), hyperoside (6, HY), myricetin (7), quercetin (8, QT). Compounds 2, 4, 5, 6 and 8 (15, 30 and 60 mg·kg−1) were orally administered to mice and the reaction was observed in tail suspension test (TST) and forced swimming test (FST). Western blot analysis was used in determination of the protein expressions of brain-derived neurotrophic factor (BDNF), tyrosine receptor kinase B (TrkB) and phosphorylation eukaryotic elongation factor 2 (p-eEF2). The results revealed that only Q-3-G and G-8-G (15, 30, 60 mg ·kg−1) significantly reduced the immobility time in FST and TST. Furthermore, Q-3-G and G-8-G remarkably increased the expression of BDNF and TrkB, and decreased the expression of p-eEF2. These results suggest that Q-3-G and G-8-G had an obvious antidepressant activity via up-regulation of BDNF expression. The new observation will provide a new direction in the development of antidepressant in the treatment of major depressive disorder (MDD).


Assuntos
Abelmoschus/química , Antidepressivos/farmacologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Flavonoides/farmacologia , Hipocampo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , China , Transtorno Depressivo Maior , Medicamentos de Ervas Chinesas/farmacologia , Etanol , Elevação dos Membros Posteriores , Hipocampo/metabolismo , Camundongos , Quercetina/análogos & derivados , Natação , Regulação para Cima
17.
J Med Virol ; 88(2): 224-33, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26185038

RESUMO

To study the epidemiology and evolution of norovirus (NoV) in immunocompromised patients in a tertiary hospital in China. Stool specimens were collected from 131 hospitalized patients presenting with diarrhea from July 1, 2012, to June 30, 2013, and were tested for NoV using RT-PCR. RT-PCR was performed to amplify the complete capsid genome for a series of samples from chronic diarrhea patients, and nucleotide and amino acid changes were analyzed. There were nine NoV-positive patients among 124 immunocompromised patients (7.3%); all nine were infected with GII.4 Sydney_2012 strain. In three chronic diarrhea patients, the GII.4 Sydney_2012 strains accumulated 19, 18, and eight nucleotide mutations within 110, 113, and 22 days, respectively, most were non-synonymous. The greatest number of stable amino acid mutations was 10 in patient 2; eight stable mutations (including three in antigenic sites) occurred while the patient was asymptomatic and shedding the virus. GII.4 Sydney_2012 strain tends to undergo stable mutations during the asymptomatic shedding phase and may generate new variants in chronic diarrhea patients.


Assuntos
Infecções por Caliciviridae/epidemiologia , Diarreia/epidemiologia , Evolução Molecular , Genótipo , Hospedeiro Imunocomprometido , Norovirus/classificação , Norovirus/genética , Adolescente , Idoso , Substituição de Aminoácidos , Pequim/epidemiologia , Infecções por Caliciviridae/virologia , Proteínas do Capsídeo/genética , Diarreia/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Mutação de Sentido Incorreto , Norovirus/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Centros de Atenção Terciária , Eliminação de Partículas Virais , Adulto Jovem
18.
J Gastroenterol Hepatol ; 31(3): 676-84, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26430807

RESUMO

BACKGROUND AND AIM: Most studies focus on gut-derived factors like microbiota and its products and how they contribute to non-alcoholic fatty liver disease (NAFLD) progression. This study investigated whether the gut-derived lymphocytes could migrate to the liver and induce liver injury in NAFLD. METHODS: A high-fat diet induced an NAFLD mouse model, and lymphocytes were labeled with 1,1-dioctadecyl-3,3,3,3 tetramethylindotricarbocyanine iodide and carboxy-fluorescein succinimidyl ester, respectively, and intravenously injected to mice to monitor lymphocyte migration. RESULTS: Adoptive transfer model results indicated that compared with lymphocytes from the spleen, bone marrow and thymus of NAFLD donor mice, mesenteric lymph nodes (MLN) cells from NAFLD donor mice predominately accumulated in the livers of NAFLD recipient mice. The frequencies of central memory CD4(+) T and CD8(+) T cells in livers of NAFLD mice were significantly increased; however, the activated T cells were not significantly altered. After adoptively transferred MLN cells, the frequencies of the activated CD4(+) T and CD8(+) T cells increased in livers of NAFLD recipient mice. By contrast, the frequencies of central memory and naïve CD4(+) T and CD8(+) T cells decreased. MLN cells also induced liver injury in NAFLD recipient mice, as reflected by elevated serum alanine aminotransferase and glutamic oxaloacetic transaminase serums. Moreover, the chemotaxis assay showed that CCL5 mediated the MLN cell migration to the liver. Also, blocking the CCL5 inhibited MLN cell migration to the liver in vitro. CONCLUSIONS: Gut-derived lymphocytes from NAFLD mice could migrate to the liver and induce liver injury and hepatic CD4(+) T and CD8(+) T cells activation. The migration was associated with the upregulation of CCL5 in the liver.


Assuntos
Fígado/citologia , Fígado/patologia , Linfócitos/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Animais , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Movimento Celular , Quimiocina CCL5/fisiologia , Modelos Animais de Doenças , Ativação Linfocitária , Masculino , Camundongos Endogâmicos C57BL , Regulação para Cima
19.
Hepatobiliary Pancreat Dis Int ; 15(1): 55-64, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26818544

RESUMO

BACKGROUND: Chronic hepatitis C virus (HCV) infection causes the skewing and activation of B cell subsets, but the characteristics of IgG+ B cells in patients with chronic hepatitis C (CHC) infection have not been thoroughly elucidated. CD4+CXCR5+ follicular helper T (Tfh) cells, via interleukin (IL)-21 secretion, activate B cells. However, the role of CD4+CXCR5+ T cells in the activation of IgG+ B cells in CHC patients is not clear. METHODS: The frequency of IgG+ B cells, including CD27-IgG+ B and CD27+IgG+ B cells, the expression of the activation markers (CD86 and CD95) in IgG+ B cells, and the percentage of circulating CD4+CXCR5+ T cells were detected by flow cytometry in CHC patients (n=70) and healthy controls (n=25). The concentrations of serum IL-21 were analyzed using ELISA. The role of CD4+CXCR5+ T cells in the activation of IgG+ B cells was investigated using a co-culture system. RESULTS: A significantly lower proportion of CD27+IgG+ B cells with increased expression of CD86 and CD95 was observed in CHC patients. The expression of CD95 was negatively correlated with the percentage of CD27+IgG+ B cells, and it contributed to CD27+IgG+ B cell apoptosis. Circulating CD4+CXCR5+ T cells and serum IL-21 were significantly increased in CHC patients. Moreover, circulating CD4+CXCR5+ T cells from CHC patients induced higher expressions of CD86 and CD95 in CD27+IgG+ B cells in a co-culture system; the blockade of the IL-21 decreased the expression levels of CD86 and CD95 in CD27+IgG+ B cells. CONCLUSIONS: HCV infection increased the frequency of CD4+CXCR5+ T cells and decreased the frequency of CD27+IgG+ B cells. CD4+CXCR5+ T cells activated CD27+IgG+ B cells via the secretion of IL-21.


Assuntos
Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Comunicação Celular , Hepatite C Crônica/imunologia , Imunoglobulina G/imunologia , Interleucinas/imunologia , Ativação Linfocitária , Receptores CXCR5/imunologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Adulto , Apoptose , Linfócitos B/metabolismo , Antígeno B7-2/sangue , Antígeno B7-2/imunologia , Biomarcadores/sangue , Relação CD4-CD8 , Linfócitos T CD4-Positivos/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Técnicas de Cocultura , Feminino , Citometria de Fluxo , Hepatite C Crônica/sangue , Hepatite C Crônica/diagnóstico , Humanos , Imunoglobulina G/sangue , Interleucinas/sangue , Masculino , Pessoa de Meia-Idade , Fenótipo , Receptores CXCR5/sangue , Transdução de Sinais , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/sangue , Receptor fas/sangue , Receptor fas/imunologia
20.
Virol J ; 12: 100, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26129991

RESUMO

BACKGROUND: Mixed cryoglobulinemia (MC) in hepatitis C virus (HCV) infection is associated with abnormal immune responses mediated by T cells and B cells, while the relationships of different subsets of CD4 + T helper (Th) cells, B cells and associated cytokines with type III asymptomatic MC in HCV infection are poorly understood. METHODS: Fifty-four chronic hepatitis C (CHC) patients and 23 healthy controls (HCs) were enrolled in the study. Serum cryoglobulins were detected by cryoprecipitation. The types of cryoglobulin were determined by western blot. The phenotypes and frequencies of Th cell and B cell subsets were detected by flow cytometric analysis. The cytokines IFN-γ, IL-4, IL-17, IL-21, IL-22, and TGF-ß were measured by enzyme-linked immunosorbent assay. RESULTS: Twenty-six CHC patients were detected with type III asymptomatic MC. The frequencies of Th2, Th17, follicular helper T (Tfh cells), Th22, and tissue-like B cells were significantly higher in CHC patients compared to HCs, while these cell subsets were not significantly different between CHC patients and HCV-related MC patients. The frequencies of Th1 and activated memory B cells increased in HCV-related MC patients compared to HCs, although the difference between the two cell subsets in CHC patients and HCs was not significant. The frequency of regulatory T cells (Treg cells) was higher in CHC patients than in HCV-related MC patients and HCs. Higher expressions of serum IFN-γ, IL-17, IL-21, and IL-22 were observed in CHC patients than in HCs, but the differences were not significantly different in CHC patients and HCV-related MC patients. The frequency of Th1 cells was associated with activated memory B cells in HCV-related MC patients, and the frequency of Th1 cells and activated memory B cells was closely related to HCV RNA in HCV-related MC patients. CONCLUSIONS: The increased frequencies of Th17 cells, Tfh cells, Th22 cells, Treg cells, cytokines IL-17, IL-21, IL-22, and tissue-like B cells, were related to HCV infection but not type III asymptomatic MC. Higher frequencies of Th1 cells and activated memory B cells were associated with type III asymptomatic MC in HCV infection.


Assuntos
Linfócitos B/imunologia , Crioglobulinemia/etiologia , Hepatite C/complicações , Hepatite C/patologia , Células Th1/imunologia , Adulto , Idoso , Western Blotting , Crioglobulinas/análise , Citocinas/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade
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