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1.
Nat Commun ; 10(1): 5492, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792210

RESUMO

Gemcitabine is the first-line treatment for locally advanced and metastatic gallbladder cancer (GBC), but poor gemcitabine response is universal. Here, we utilize a genome-wide CRISPR screen to identify that loss of ELP5 reduces the gemcitabine-induced apoptosis in GBC cells in a P53-dependent manner through the Elongator complex and other uridine 34 (U34) tRNA-modifying enzymes. Mechanistically, loss of ELP5 impairs the integrity and stability of the Elongator complex to abrogate wobble U34 tRNA modification, and directly impedes the wobble U34 modification-dependent translation of hnRNPQ mRNA, a validated P53 internal ribosomal entry site (IRES) trans-acting factor. Downregulated hnRNPQ is unable to drive P53 IRES-dependent translation, but rescuing a U34 modification-independent hnRNPQ mutant could restore P53 translation and gemcitabine sensitivity in ELP5-depleted GBC cells. GBC patients with lower ELP5, hnRNPQ, or P53 expression have poor survival outcomes after gemcitabine chemotherapy. These results indicate that the Elongator/hnRNPQ/P53 axis controls gemcitabine sensitivity in GBC cells.

2.
Biomed Res Int ; 2019: 8146937, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31871943

RESUMO

Background and Aims: Traditional Chinese medicine (TCM) has been widely applied in chronic hepatitis B (CHB) supplementary treatment in China. Kidney yang deficiency syndrome (KYDS), one of the most common TCM syndromes of CHB, is more likely to progress to liver cirrhosis or hepatocellular carcinoma than other syndromes. Polymorphisms in the human leucocyte antigen- (HLA-) DQB1 and -DRB1 genes were reported to be associated with hepatitis B virus infection outcomes. Here, we investigated whether HLA-DQB1 and HLA-DRB1 are associated with the classification of CHB TCM syndromes. Methods: We genotyped HLA-DQB1 and HLA-DRB1 alleles in a total of 105 subjects, including 74 CHB patients (28 KYDS and 46 non-KYDS) and 31 healthy individuals from Sichuan Province of Southwest China, by polymerase chain reaction sequence-based typing (PCR-SBT). Moreover, a meta-analysis was carried out for further verification. Results: The proportion of patients with high HBV DNA load (≥2000 IU/ml) in the KYDS group is higher than that in the non-KYDS group (60.70% [17/28] vs. 28.30% [13/46]); P=0.01). The frequencies of HLA-DQB1∗02:01 (P=0.04) and HLA-DRB1∗03:01 (P=0.04) in the KYDS group were significantly increased compared to the non-KYDS group. The gene test and meta-analysis showed that HLA-DRB1∗08:03 confers susceptibility to CHB (odds ratio = 1.57). Conclusion: We found an association between HLA-DRB1/DQB1 polymorphisms and KYDS of CHB. Moreover, KYDS patients of CHB are characteristic with high HBV DNA loads. These findings help to reveal the biological mechanism of KYDS in high risk of CHB progression and suggest a potential prognostic value for disease outcome evaluation.

4.
BMC Infect Dis ; 19(1): 961, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711425

RESUMO

BACKGROUND: Clostridioides difficile is considered the main pathogen responsible for hospital-acquired infections. This prospective study determined the prevalence, molecular epidemiological characteristics, and risk factors for C. difficile infection (CDI) and C. difficile colonization (CDC) among patients in the intensive care unit (ICU) of a large-scale tertiary hospital in China, with the aim of providing strategies for efficient CDI and CDC prevention and control. METHODS: Stool samples were collected and anaerobically cultured for C. difficile detection. The identified isolates were examined for toxin genes and subjected to multilocus sequence typing. Patients were classified into CDI, CDC, and control groups, and their medical records were analyzed to determine the risk factors for CDI and CDC. RESULTS: Of the 800 patients included in the study, 33 (4.12%) and 25 (3.12%) were identified to have CDI and CDC, respectively. Associations with CDI were found for fever (OR = 13.993), metabolic disorder (OR = 7.972), and treatment with fluoroquinolone (OR = 42.696) or combined antibiotics (OR = 2.856). CDC patients were characterized by prolonged hospital stay (OR = 1.137), increased number of comorbidities (OR = 36.509), respiratory diseases (OR = 0.043), and treatment with vancomycin (OR = 18.168). Notably, treatment with metronidazole was found to be a protective factor in both groups (CDI: OR = 0.042; CDC: OR = 0.013). Eighteen sequence types (STs) were identified. In the CDI group, the isolated strains were predominantly toxin A and toxin B positive (A + B+) and the epidemic clone was genotype ST2. In the CDC group, the dominant strains were A + B+ and the epidemic clone was ST81. CONCLUSIONS: The prevalences of CDC and CDI in our ICU were relatively high, suggesting the importance of routine screening for acquisition of C. difficile. Future prevention and treatment strategies for CDC and CDI should consider hospital stay, enteral nutrition, underlying comorbidities, and use of combined antibiotics. Moreover, metronidazole may be a protective factor for both CDI and CDC, and could be used empirically.

5.
Clin Immunol ; 209: 108267, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31639448

RESUMO

Treg is essential to limit the extend and duration of the immune response, but its stability is still under debate. Here we demonstrate that IL-17-producing Treg cells (Th17-like cells) increased in peripheral blood of patients with Systemic Lupus Erythematosus (SLE). Notably, the Th17-like cells from patient with active SLE were characterized with some phenotype and function of Th17 cells. Upon stimulation, Helios-Foxp3 + CD4+ T cells decrease Foxp3 expression but increase expression of IL-17 and RORγt. Damage associated molecule pattern and inflammatory cytokines are important for induction of IL-17 expression in Treg cells. The Th17-like cells from patients with active SLE lose suppressive function and have robust response to stimulation of autoantigens. We also observed that the level of Th17-like cells in peripheral blood is closely associated with the clinical index of SLE. These findings suggest that instability of Treg plays a critical role in pathogenesis of autoimmune diseases.

6.
Dev Comp Immunol ; 93: 18-27, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30571995

RESUMO

Candida albicans is one of the most common fungal pathogens of humans. Currently, there are limitations in the evaluation of C. albicans infection in existing animal models, especially in terms of understanding the influence of specific infectious stages of the fungal pathogen on the host. We show that C. albicans infects, grows and invades tissues in the planarian flatworm Schmidtea mediterranea, and that the planarian responds to infection by activating components of the host innate immune system to clear and repair host tissues. We study different stages of C. albicans infection and demonstrate that planarian stem cells increase division in response to fungal infection, a process that is likely evolutionarily conserved in metazoans. Our results implicate MORN2 and TAK1/p38 signaling pathways as possible mediators of the host innate immune response to fungal infection. We propose the use of planarians as a model system to investigate host-pathogen interactions during fungal infections.


Assuntos
Candida albicans/imunologia , Candidíase/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata/imunologia , Planárias/imunologia , Animais , Candida albicans/crescimento & desenvolvimento , Candidíase/microbiologia , Modelos Animais de Doenças , Proteínas Nucleares/metabolismo , Membro 2 do Grupo C da Subfamília 2 de Receptores Nucleares/metabolismo , Planárias/microbiologia , Células-Tronco/citologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
7.
BMC Infect Dis ; 18(1): 207, 2018 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-29724187

RESUMO

BACKGROUND: Intestinal colonization by pathogenic bacteria is a risk factor for infection, and contributes to environmental contamination and disease dissemination. Alteration of gut microbiota also plays a pivotal role in the development of disease. Although Clostridium difficile and Staphylococcus aureus are well-recognized pathogens causing nosocomial and community infections, the intestinal colonization was not fully investigated. Herein, we explored their overall carriage rates in healthy adults from the community, and characterized the gut microbiomes of C. difficile and S. aureus carriers. METHODS: Fecal samples were collected from 1709 healthy volunteers from communities in Shanghai, China, and tested for the presence of C. difficile, methicillin-sensitive S. aureus (MSSA), and methicillin-resistant S. aureus (MRSA) using culture-based techniques. To explore differences in the gut microbiome, 16S rRNA gene sequencing was conducted using samples from non-carriers (CH), C. difficile carriers (CCD), MRSA carriers (CM), and MSSA carriers (CS). RESULTS: Overall, we detected 12 C. difficile and 60 S. aureus isolates, accounting for 0.70% and 3.51% of total isolates, respectively. Eight isolates were determined to be MRSA, accounting for 13.3% of the S. aureus population. Sequencing data revealed that the microbial diversity and richness were similar among the four groups. However, at the phylum level, carriage of C. difficile or MRSA was associated with a paucity of Bacteroidetes and an overabundance of Proteobacteria compared with non-carriers. At the genus level, the prevalence of the genera Bacteroides, Prevotella, Faecalibacterium, and Roseburia was decreased in C. difficile-positive samples compared with the controls, while the proportion of Clostridium cluster XIVa species was increased. MRSA carriers exhibited a higher proportion of the genera Parasutterella and Klebsiella, but a decreased prevalence of Bacteroides. Compared with MSSA carriers, Klebsiella was the only genus found to be significantly enriched in MRSA carriers. CONCLUSIONS: In healthy adults, colonization by C. difficile or S. aureus did not significantly affect gut microbiota diversity. However, the alteration of the gut microbiota composition in C. difficile carriers could indicate a predisposition to further infection. Our study provides essential data on the prevalence and effects of C. difficile and S. aureus colonization on gut microbiota composition in healthy adults.


Assuntos
Clostridium difficile/patogenicidade , Microbioma Gastrointestinal , Staphylococcus aureus/patogenicidade , Adolescente , Adulto , Idoso , Bacteroides/genética , Biodiversidade , China , Clostridium difficile/genética , Clostridium difficile/isolamento & purificação , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/genética , Humanos , Intestinos/microbiologia , Masculino , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética , Staphylococcus aureus/genética
8.
FEMS Yeast Res ; 18(4)2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29648590

RESUMO

The transcriptional regulator Pdr1 plays a positive role in regulating azole drug resistance in Candida glabrata. Previous studies have shown the importance of the carboxyl (C)-terminal sequence of Pdr1 in fulfilling its function, as this region mediates interactions between Pdr1 and the co-activator Gal11A and is crucial for activation of Pdr1 targets. However, mechanisms of how Pdr1 is regulated, especially implication of its C-terminus in the regulatory activity, remain uncharacterized. In this study, we unexpectedly observed that the C-terminal modification of Pdr1 in an azole-resistant clinical isolate harboring a single GOF mutation, resulted in adverse effects such as decreased expression levels of Pdr1, downregulation of Pdr1 targets and azole hypersensitivity. Importantly, the C-terminal 3 × FLAG tagging significantly decreased the binding of Pdr1 to the pleiotropic drug response elements in its own promoter, promoted an irregular cellular mislocalization and thereby disrupted the transcriptional autoregulation of this master regulator. Unexpectedly, the aberrant cytoplasmic localization caused a non-functional interaction with Gal11A, a co-activator involved in drug resistance. Based on these findings, we proposed that C-terminal sequence of Pdr1 is vital for its stability and functionality, and targeting regulation of this region may represent a promising future strategy for combating C. glabrata infection and drug resistance.


Assuntos
Azóis/farmacologia , Candida glabrata/efeitos dos fármacos , Candida glabrata/genética , Farmacorresistência Fúngica , Regulação Fúngica da Expressão Gênica , Homeostase , Fatores de Transcrição/metabolismo , Análise Mutacional de DNA , Perfilação da Expressão Gênica , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Fatores de Transcrição/genética
9.
Sci Rep ; 8(1): 4187, 2018 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-29520099

RESUMO

Given the challenges in exploring lifelong therapy with little side effect for human immunodeficiency virus infection and acquired immune deficiency syndrome (HIV/AIDS) cases, there is increasing interest in developing traditional Chinese medicine (TCM) treatments based on specific TCM syndrome. However, there are few objective and biological evidences for classification and diagnosis of HIV/AIDS TCM syndromes to date. In this study, iTRAQ-2DLC-MS/MS coupled with bioinformatics were firstly employed for comparative proteomic profiling of top popular TCM syndromes of HIV/AIDS: accumulation of heat-toxicity (AHT) and Yang deficiency of spleen and kidney (YDSK). It was found that for the two TCM syndromes, the identified differential expressed proteins (DEPs) as well as their biological function distributions and participation in signaling pathways were significantly different, providing biological evidence for the classification of HIV/AIDS TCM syndromes. Furthermore, the TCM syndrome-specific DEPs were confirmed as biomarkers based on western blot analyses, including FN1, GPX3, KRT10 for AHT and RBP4, ApoE, KNG1 for YDSK. These biomarkers also biologically linked with the specific TCM syndrome closely. Thus the clinical and biological basis for differentiation and diagnosis of HIV/AIDs TCM syndromes were provided for the first time, providing more opportunities for stable exertion and better application of TCM efficacy and superiority in HIV/AIDS treatment.


Assuntos
Síndrome de Imunodeficiência Adquirida/sangue , Medicina Tradicional Chinesa/métodos , Proteômica , Espectrometria de Massas em Tandem , Síndrome de Imunodeficiência Adquirida/diagnóstico , Síndrome de Imunodeficiência Adquirida/terapia , Adulto , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Mycoses ; 61(7): 430-440, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29464833

RESUMO

Recently, Candida glabrata has emerged as a health-threatening pathogen and the rising resistance to antifungal agent in C. glabrata often leads to clinical treatment failure. To investigate the evolution of drug resistance and adherence ability in four paired clinical isolates collected before and after antifungal treatment. Sequence analysis, gene disruption, drug-susceptibility, adhesion tests and real-time quantitative PCR were performed. The azole-susceptible strains acquired azole resistance after antifungal therapy. Four gain-of-function (GOF) mutations in CgPDR1 were revealed by sequence analysis, namely G1099D, G346D, L344S and P927S, the last being reported for the first time. CDR1, CDR2 and SNQ2 efflux pump gene expression levels were elevated in strains harbouring GOF mutations in CgPDR1, resulting in decreased azole susceptibility. CgPDR1 alleles with distinct GOF mutations displayed different expression profiles for the drug-related genes. CgPDR1GOF mutations led to increased efflux pumps expression levels in a strain background independent way. Hyperactive Pdr1G1099D and Pdr1P927S displayed strain background-dependent increased adherence to host cells via upregulation of EPA1 transcription. Interestingly, the drug transporter gene expression levels did not always correspond with that of the adhesin EPA1 gene. GOF mutations in CgPDR1 conferred drug resistance and increased adherence in the clinical strains, possibly endowing C. glabrata with increased viability and pathogenicity.


Assuntos
Azóis/farmacologia , Candida glabrata/genética , Candida glabrata/fisiologia , Adesão Celular , Farmacorresistência Fúngica Múltipla/genética , Mutação com Ganho de Função , Azóis/uso terapêutico , Candida glabrata/efeitos dos fármacos , Candida glabrata/patogenicidade , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Proteínas de Ligação a DNA/genética , Proteínas Fúngicas/genética , Humanos , Lectinas/genética , Proteínas de Membrana Transportadoras/genética
11.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 31(12): 1500-1505, 2017 12 15.
Artigo em Chinês | MEDLINE | ID: mdl-29806395

RESUMO

Objective: To observe the effect of bone marrow mesenchymal stem cells (BMSCs) conditioned medium on microglia (MGs) and its secretion of arginase 1 (Arg1). Methods: The BMSCs separated through differential adhesion method from the femur and tibia marrow of 4-week-old Sprague Dawley (SD) rats were cultured and identified by Vimentin immunofluorescence staining; whereas MGs separated through trypsin digestion method from the brain of 3-day-old SD rats were cultured and identified by Iba1 immunofluorescence staining. The primary MGs were cultured with DMEM/F12 medium containing BMSCs conditioned medium (experimental group) and with single DMEM/F12 medium (control group), respectively. After 48 hours of culture, the morphology of MGs was observed by inverted phase contrast microscope, the activated state of MGs was detected by using Iba1 immunofluorescence staining, and Arg1 expression of MGs was assessed by Iba1-Arg1 double-labelling immunofluorescence staining and Western blot method. Results: Inverted phase contrast microscope observation showed that BMSCs entered logarithmic growth phase at 14 days after culture, and more than 98% cells were positive to Vimentin immunofluorescence staining; whereas MGs entered logarithmic growth phase at 21 days after culture, and around 80% cells were positive to Iba1 immunofluorescence staining. Inverted phase contrast microscope observation displayed that in the experimental group, MGs were activated with increased size of soma, shortened process, and amoeba change. Immunofluorescence staining displayed that the Iba1 positive cells number in the experimental group was significantly higher than that in the control group ( t=0.007, P=0.000); double-labelling immunofluorescence staining revealed that the Iba1-Arg1 positive cells number in the experimental group was significantly higher than that in the control group ( t=0.007, P=0.000); and Western blot results elucidated that the relative expression of Arg1 protein in the experimental group was significantly higher than that in the control group ( t=0.001, P=0.000). Conclusion: BMSCs conditioned medium can activate MGs and induce MGs to express Arg1.


Assuntos
Arginase/metabolismo , Células-Tronco Mesenquimais , Microglia , Animais , Células da Medula Óssea , Diferenciação Celular , Células Cultivadas , Meios de Cultivo Condicionados , Ratos , Ratos Sprague-Dawley
12.
Cell Immunol ; 311: 36-45, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27743606

RESUMO

Similar to programmed death-1 (PD-1), B and T lymphocyte attenuator (BTLA) is a co-inhibitory molecule of the CD28 family. PD-1 is involved in T cell exhaustion during chronic viral infection. However, the role of BTLA in virus-specific T cells is poorly defined. Here we investigated the expression and function of BTLA in T cells from patients with chronic hepatitis B virus (HBV) infection. The phenotype of peripheral and intrahepatic HBV-specific T cells from 43 patients with chronic HBV infection was assessed by flow cytometry. Functional evaluation was analyzed by T cell expansion and cytokine secretion after different treatments. In chronic HBV patients, a subset of inefficient interferon-γ producing antigen-specific CD8+ T cells recruited to the liver expressed high BTLA levels. The BTLA+ HBV-specific CD8+ T cell suppressive function was antigen-specific, at least in the induction phase, because they were only activated by a pool of HBV peptides but not with a pool of unrelated peptides. Suppression of T cell responses was restored by a BTLA signaling blockade and neutralizing IL-10, indicating that BTLA signaling-mediated IL-10 secretion plays a key role in suppression. This study provides important evidence that there is a subset of liver infiltrated virus-specific CD8+BTLA+ regulatory T cells in patients with chronic HBV infection. This subset of cells plays a pivotal role in controlling hepatic effector CD8+ T cell responses through BTLA signaling mediated regulatory factor IL-10 production.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Fígado/patologia , Receptores Imunológicos/metabolismo , Adulto , Linfócitos T CD8-Positivos/virologia , Proliferação de Células , Células Cultivadas , Citocinas/metabolismo , Feminino , Humanos , Imunossupressão , Interleucina-10/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Receptores Imunológicos/genética , Transdução de Sinais , Adulto Jovem
13.
Diagn Microbiol Infect Dis ; 86(4): 428-433, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27681363

RESUMO

OBJECTIVES: To characterize extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli isolates from the community, determine their antibiotic sensitivity profiles and quinolone resistance mechanisms, and identify any horizontal transfer of ESBL genes. METHODS: One thousand seven hundred thirty-two stool samples were collected from healthy individuals in 6 communities and 2 physical examination centers in Shanghai, China. ESBL-producing E. coli was screened and confirmed by confirmatory test and E. coli-identifying agars. PCR was used to amplify ESBL-encoding genes blaCTX-M, blaTEM, blaSHV genes, and quinolone resistance-relating genes gyrA, gryB, parC, parE, qnrS, aac (6')-Ib-cr, oqxA, and oqxB, followed by sequencing. Antimicrobial susceptibility tests and conjugation assays were also performed. RESULTS: Overall, 528 isolates were identified as ESBL-producing E. coli, and all were positive for blaCTX-M. CTX-M-14 was found most frequently (48.9%). S83L±D87N in gyrA and S80I in parC were the most common topoisomerase mutations. Plasmid-mediated quinolone resistance (PMQR) determinants were also detected, including qnrS1 (11.7%), qnrS2 (3.7%), aac (6')-Ib-cr(12.8%), oqxA(8.5%), and oqxB(11.0%). The rate of multidrug resistance was very high (92.2%). ESBL genes transferred successfully in 39.4% isolates. CONCLUSIONS: There is a high prevalence of fecal carriage of ESBL-producing E. coli in the community in Shanghai, with high-level quinolone resistance and CTX-M-14 being the predominant CTX-M enzyme.


Assuntos
Antibacterianos/farmacologia , Portador Sadio/epidemiologia , Infecções Comunitárias Adquiridas/epidemiologia , Farmacorresistência Bacteriana , Infecções por Escherichia coli/epidemiologia , Escherichia coli/efeitos dos fármacos , Quinolonas/farmacologia , beta-Lactamases/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Portador Sadio/microbiologia , China/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Escherichia coli/enzimologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Feminino , Transferência Genética Horizontal , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Plasmídeos/análise , Reação em Cadeia da Polimerase , Prevalência , Análise de Sequência de DNA , Adulto Jovem
14.
Microbiol Res ; 192: 65-72, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27664724

RESUMO

Recently, the proportion of Candida tropicalis in clinical isolates has significantly increased. Some C. tropicalis strains colonize the skin or mucosal surfaces as commensals; others trigger invasive infection. To date, the pathogenicity of C. tropicalis has not been thoroughly researched. This study reports several virulence factors, including biofilm and hyphae formation, proteinase, phospholipase, lipase and hemolytic activity, in 52 clinical isolates of C. tropicalis collected from five hospitals in four provinces of China. Some C. tropicalis tended to produce more hyphae than others in the same circumstance. Six C. tropicalis strains with different morphologies were injected into mice via the tail vein, and the survival proportions and fungal burdens of the strains were evaluated. Hyphal production by C. tropicalis was associated with stronger virulence. RNA sequencing revealed that C. tropicalis with more hyphae up-regulated several genes involved in morphological differentiation and oxidative response, including IF2, Atx1, and Sod2. It appears that hyphal formation plays a vital role in the pathogenicity of C. tropicalis, and interacts with the oxidative stress response to strengthen the organism's virulence.


Assuntos
Candida tropicalis/fisiologia , Perfilação da Expressão Gênica , Hifas/genética , Transcriptoma , Animais , Biofilmes , Candida tropicalis/patogenicidade , Candidíase/microbiologia , Análise por Conglomerados , Biologia Computacional/métodos , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Camundongos , Reprodutibilidade dos Testes , Virulência/genética , Fatores de Virulência/genética
15.
Biosci Biotechnol Biochem ; 80(12): 2334-2337, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27554967

RESUMO

Alzheimer's disease (AD) is the most common cause of dementia. Its pathology often accompanies inflammatory action, and astrocytes play important roles in such procedure. Rela(p65) is one of significant message factors in NF-κB pathway which has been reported high expression in astrocyte treated by Aß. HupA, an alkaloid isolated from Chinese herb Huperzia serrata, has been widely used to treat AD and observations reflected that it improves memory and cognitive capacity of AD patients. To reveal its molecular mechanisms on p65, we cultured astrocytes, built Aß-induced AD model, treated astrocytes with HupA at different concentrations, assayed cell viability with MTT, and detected p65 expression by immunohistochemistry and PCR. Our results revealed that treatment with 10 µM Aß1-42 for 24 h induced a significant increase of NF-κB in astrocytes; HupA significantly down-regulated p65 expression induced by Aß in astrocytes. This study infers that HupA can regulate NF-κB pathway to treat AD.


Assuntos
Alcaloides/farmacologia , Peptídeos beta-Amiloides/farmacologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Fragmentos de Peptídeos/farmacologia , Sesquiterpenos/farmacologia , Fator de Transcrição RelA/metabolismo , Animais , Camundongos
16.
Mycopathologia ; 181(11-12): 833-838, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27538831

RESUMO

Azole resistance of Candida tropicalis has, in recent years, become a serious issue in hospitals; however, there is limited knowledge of the mechanisms underlying this resistance. We have previously demonstrated that ERG11 plays a vital role in azole resistance in C. tropicalis. Here, we describe the expression and sequence variation of UPC2, which encodes a transcription factor of ERG11. Quantitative real-time RT-PCR showed that 31 azole-resistant C. tropicalis strains significantly overexpressed UPC2. Those isolates resistant to all three azole antifungals upregulated UPC2 expression to a greater degree than those resistant to only fluconazole or itraconazole. The UPC2 promoter contains mutations -118T-G and -155G-A in azole-resistant strains of C. tropicalis. Meanwhile, the mutation G392E was also detected twice in UPC2 gene in azole-resistant C. tropicalis and was demonstrated to mediate azole antifungal susceptibility by using Saccharomyces cerevisiae as an expression host, particularly for fluconazole and itraconazole.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Candida tropicalis/efeitos dos fármacos , Candida tropicalis/genética , Farmacorresistência Fúngica , Regulação Fúngica da Expressão Gênica , Transativadores/análise , Perfilação da Expressão Gênica , Mutação de Sentido Incorreto , Mutação Puntual , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase em Tempo Real , Transativadores/genética
17.
Mycopathologia ; 181(7-8): 475-84, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26886444

RESUMO

Both statistical and molecular biological methods were used to evaluate the association between Candida colonization of different body sites and invasive candidiasis (IC) and analyse the potential infection sources of IC. Candida surveillance cultures from the urine, sputum, rectum and skin were performed on patients admitted to an emergency intensive care units (EICU) of a tertiary care hospital in Shanghai, China, from February 2014 to January 2015. Specimens were collected once a week at admission and thereafter. The patients' clinical data were collected, and Candida isolates were genotyped using polymorphic microsatellite markers. A total of 111 patients were enrolled. Patients with positive urine (23.3 vs. 2.5 %, p = 0.001) and rectal swab (13.6 vs. 0 %, p = 0.010) cultures were more likely to develop IC. However, the risk for IC was not significantly different among patients with and without respiratory (10.0 vs. 5.8 %, p = 0.503) and skin (33.3 vs. 6.5 %, p = 0.056) colonization. Gene microevolution frequently occurred at rectal swab and urine sites, and IC with possible source of infection was caused by rectal isolates (2/7), urine isolates (4/7) and sputum isolate (1/7).The colonization of gut and urinary tract maybe more relevant indicators of IC, which should be taken into consideration when selecting practical body sites for Candida surveillance cultures.


Assuntos
Candida/isolamento & purificação , Candidíase Invasiva/epidemiologia , Portador Sadio/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Candida/classificação , Candida/genética , Candidíase Invasiva/microbiologia , Portador Sadio/microbiologia , China/epidemiologia , Serviço Hospitalar de Emergência , Feminino , Genótipo , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Reto/microbiologia , Sistema Respiratório/microbiologia , Medição de Risco , Pele/microbiologia , Centros de Atenção Terciária , Urina/microbiologia
18.
Anaerobe ; 34: 1-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25817005

RESUMO

Clostridium difficile is well recognized as the common pathogen of nosocomial diarrhea, meanwhile, asymptomatic colonization with C. difficile in part of the population has also drawn public attention. Although gut microbiota is known to play an important role in the pathogenesis of C. difficile infection (CDI), whether there is any alteration of gut microbial composition in asymptomatic C. difficile carriers hasn't been clearly described. The purpose of this study was to explore the differences in gut microbiome among CDI patients, asymptomatic C. difficile carriers and healthy individuals. We performed fecal microbiota analysis on the samples of eight CDI patients, eight asymptomatic C. difficile carriers and nine healthy subjects using 16S rRNA gene pyrosequencing. CDI patients and asymptomatic carriers showed reduced microbial richness and diversity compared with healthy subjects, accompanied with a paucity of phylum Bacteroidetes and Firmicutes as well as an overabundance of Proteobacteria. Some normally commensal bacteria, especially butyrate producers, were significantly depleted in CDI patients and asymptomatic carriers. Furthermore, the differences observed in microbial community structure between CDI patients and asymptomatic carriers suggested that the gut microbiota may be a potential factor of disease state for CDI. Our study demonstrates the characterization and diversity of gut microbiota in CDI and asymptomatic C. difficile colonization, which will provide new ideas for surveillance of the disease state and development of microbiota-targeted agents for CDI prevention and treatment.


Assuntos
Portador Sadio/microbiologia , Infecções por Clostridium/microbiologia , Clostridium difficile/crescimento & desenvolvimento , Microbioma Gastrointestinal , Microbiota , Adulto , Idoso , Idoso de 80 Anos ou mais , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Fezes/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
19.
Mycopathologia ; 179(5-6): 407-14, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25720562

RESUMO

In this study, fungemia cases from four tertiary hospitals located in Shanghai and Anhui province in China from March 2012 to December 2013 were enrolled to investigate clinical features, species distribution, antifungal susceptibility and strain relatedness. During the study period, 137 non-duplicate cases and their corresponding isolates were collected. Six different genera of fungi were identified, of which Candida spp. were the most common (126/137, 91.97 %), with C. albicans predominating (48/137, 35.03 %). The non-Candida fungi rate reached 8.03 % (11/137), and Pichia spp. was the most common (5/137, 3.65 %). Compared with C. albicans, non-C. albicans fungi-associated fungemia was more likely in younger (p = 0.004) and male patients (χ (2) = 6.2618, p = 0.0123) and patients from ICUs (χ (2) = 6.3783, p = 0.0116). Overall, the susceptible/WT rates of common Candida spp. to fluconazole, itraconazole, voriconazole, flucytosine, amphotericin B and caspofungin were 74.63, 92.31, 93.16, 96.58, 100 and 95.69 %, respectively. C. tropicalis and C. guilliermondii had a low susceptibility to fluconazole: 79.95 and 77.78 %, respectively. No isolates were resistant/WT to caspofungin, but C. parapsilosis and C. guilliermondii had high MIC90 values; 1 and 2 mg/L, respectively. In terms of genotyping, MLST was taken for C. glabrata and C. tropicalis, while microsatellite marker analysis was used for C. albicans and C. parapsilosis. C. glabrata was predominantly clone ST7, accounting for 75 %, while the other isolates showed genetic diversity. Considering the increased proportion of non-C. albicans fungi and the presence of endemic clones of C. glabrata, it is essential to undertake additional surveillance of fungemia.


Assuntos
Fungemia/epidemiologia , Fungemia/microbiologia , Fungos/classificação , Fungos/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Antifúngicos/farmacologia , China/epidemiologia , Análise por Conglomerados , Feminino , Fungos/efeitos dos fármacos , Fungos/genética , Genótipo , Humanos , Masculino , Testes de Sensibilidade Microbiana , Repetições de Microssatélites , Pessoa de Meia-Idade , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Técnicas de Tipagem Micológica , Estudos Retrospectivos , Centros de Atenção Terciária
20.
Chin Med J (Engl) ; 127(9): 1601-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24791861

RESUMO

BACKGROUND: Over the last decade, Clostridium difficile infection (CDI) has emerged as a significant nosocomial infection, yet little has been reported from China. This study aimed to characterize the clinical and microbiological features of CDI from a hospital in Shanghai. METHODS: Patients with CDI seen between December 2010 and March 2013 were included in this study, of which clinical data were retrospectively collected. The microbiological features of corresponding isolates were analyzed including genotype by multi-locus sequence typing (MLST), antimicrobial susceptibility, toxin production, sporulation capacity, biofilm formation, and motility. RESULTS: Ninety-four cases of CDI were included during this study period, 12 of whom were severe cases. By reviewing the clinical data, all patients were treated empirically with proton pump inhibitor or antibiotics or both, and they were distributed widely across various wards, most frequently to the digestive ward (28/94, 29.79%). Comparing the severe with mild cases, no significant differences were found in the basic epidemiological data or the microbiological features. Among the 94 isolates, 31 were toxin A-negative toxin B-positive all genotyped as ST37. They generated fewer toxins and spores, as well as similar amounts of biofilm and motility percentages, but exhibited highest drug resistance to cephalosporins, quinolones, macrolide-lincosamide and streptogramin (MLSB), and tetracycline. CONCLUSIONS: No specific clinical genotype or microbiological features were found in severe cases; antimicrobial resistance could be the primary reason for epidemic strains leading to the dissemination and persistence of CDI.


Assuntos
Clostridium difficile/genética , Clostridium difficile/isolamento & purificação , Tipagem de Sequências Multilocus/métodos , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Cefalosporinas/farmacologia , China , Clostridium difficile/efeitos dos fármacos , Genótipo , Quinolonas/farmacologia , Atenção Terciária à Saúde/estatística & dados numéricos , Tetraciclina/farmacologia
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