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1.
J Clin Lab Anal ; 34(11): e23494, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32696587

RESUMO

BACKGROUND: The distributions of methicillin-susceptible Staphylococcus aureus (MSSA) are divers geographically with different genetic backgrounds. Data related to molecular characteristics of MSSA compare to methicillin-resistant Staphylococcus aureus (MRSA) is sparse. METHODS: In this cross-sectional study, antimicrobial susceptibility testing, virulence genes analysis, biofilm formation, accessory gene regulator (agr) typing, and multilocus sequence typing (MLST) characterized on 75 MSSA isolates. RESULTS: Multidrug-resistance MSSA was found to be 84%. Forty-eight (64%) isolates were toxinogenic with 34 and 14 isolates carrying pvl and tst representing 45.3% and 18.7%. The most common SE genes were sed (20%), sec (16%), and sea (16%). Fifty-five (73.3%) isolates were confirmed as biofilm producer with a markedly high prevalence of fnbA (93.3%), fnbB (86.7%), icaA (65.3%), icaD (53.3%), can (24%), ebp (10.7%), and bap (1.3%). A total of 3 agr types (I, 73.3%; III, 16%; II, 10.7%) and 4 clonal complexes (CCs) and sequence types (STs), namely CC8/ST293 (45.3%), CC/ST22 (28%), CC/ST30 (16%), and CC/ST5 (10.7%) were detected in this study. All the high and low-level mupirocin resistance strains belonged to ST239 and ST22 strains, respectively. All the fusidic acid-resistant isolates carried fusC and belonged to ST30. CONCLUSIONS: These findings indicated that ST239 with strong biofilm production ability is the most common type in MSSA strains isolated from patients. It seems that the antimicrobial resistance profiles, toxin, and biofilm formation were closely associated with specific STs. Further studies are required to identify and control of these clonal lineages in our area.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Infecções Estafilocócicas , Staphylococcus aureus , Biofilmes , Estudos Transversais , Humanos , Irã (Geográfico) , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidade , Fatores de Virulência/genética
2.
PLoS Negl Trop Dis ; 14(1): e0007843, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31929528

RESUMO

BACKGROUND: Neglected parasitic diseases (NTDs) like cutaneous leishmaniasis (CL) have caused high mortality and morbidity rate in developing countries. This disease is considered as one of the six major tropical diseases, and has a great importance in HIV infected individuals as an opportunistic infection in those areas that both infections are endemic. This study evaluated the therapeutic effects of the Urtica dioica L (U. dioica) aqueous extract as an anti-leishmanial herbal drug in-vitro and in-vivo, and in addition to that, evaluated two vital immune system cytokines including gamma interferon (IFN-γ) and interleukin-4 (IL-4) plus nitric oxide (NO) and arginase activity against Leishmania major (L. major) infected mice. METHODOLOGY/PRINCIPAL FINDINGS: In-vitro anti-leishmanial activity of U. dioica aqueous extract was determined using MTT method and also Parasite Rescue Transformation Assay. Also, the footpad lesion size and parasite load in BALB/c mice infected with L. major were quantified for in-vivo assessment. Furthermore, for evaluating the immune responses, the levels of IFN-γ, IL-4, NO and arginase were measured in the BALB/c mice. These results indicated that U. dioica extract significantly reduced the L. major promastigotes viability. According to the in-vitro cytotoxicity assay of the extract on Leishmania parasites (CC50) and infected macrophages (EC50), the extract had no toxicity to the macrophages, however it efficiently killed the L. major amastigotes. In addition, the lesion size, parasite load, IL-4, and ARG were decreased in the treated infected mice, however IFN-γ and NO were significantly increased. CONCLUSIONS/SIGNIFICANCE: This study established satisfactory results in Leishmania parasite clearing both in-vivo and in-vitro. Therefore, U. dioica extract can be considered as an effective and harmless herbal compound for killing the parasite without toxicity to the host macrophages. Furthermore, it also can treat the CL by switching the mouse immune response towards a cell-mediated response (Th1); hence, it may be identified as a perfect therapeutic herbal drug for CL treatment.


Assuntos
Leishmania major/efeitos dos fármacos , Extratos Vegetais/farmacologia , Urtica dioica/química , Animais , Antiprotozoários/farmacologia , Arginase/metabolismo , Linhagem Celular , Interferon gama/metabolismo , Interleucina-4/metabolismo , Leishmaniose Cutânea/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/metabolismo , Carga Parasitária , Extratos Vegetais/toxicidade , Urtica dioica/toxicidade
3.
J Cell Physiol ; 234(2): 1208-1218, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30132888

RESUMO

There is information regarding the rates of gastric cancer (GC) in different populations and the important role of Helicobacter pylori in GC development; however, no comprehensive study has yet been performed to investigate the prevalence of GC in H. pylori-infected patients. PubMed, Embase, and Cochrane Library through January 1, 2000 were searched without language restrictions. Quality of included studies was assessed with a critical appraisal checklist recommended by the Joanna Briggs Institute. All of the analyses were conducted using Comprehensive Meta-Analysis Software Version 2.0 and Stata 14.0. Forty-four studies from 17 countries were included. The pooled frequency of GC was 17.4% (95% confidence interval: 16.4-18.5) in H. pylori-infected population. The frequency of GC among H. pylori-infected population varied markedly across countries. The highest rate of GC was observed in H. pylori-infected individuals from Asian countries. The frequency of GC was relatively high in H. pylori-infected population in the world. However, the eradication of H. pylori might be a promising strategy for GC prevention, especially in high-risk populations such as Asian countries.


Assuntos
Saúde Global , Infecções por Helicobacter/epidemiologia , Helicobacter pylori/patogenicidade , Neoplasias Gástricas/epidemiologia , Adulto , Idoso , Feminino , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Helicobacter pylori/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/prevenção & controle
4.
Infez Med ; 26(4): 329-335, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30555136

RESUMO

Wide distrubution of multidrug-resistant Acinetobacter baumannii strains has become a foremost concern in hospital environments. Treatment of infections caused by multidrug resistant strains has conventionally involved the use of ß-lactams such as carbapenems. In this study, we report the distribution of carbapenemase genes in A. baumannii isolated from hospitalized patients. The study was conducted on 110 non-repetitive A. baumannii isolates collected from hospitalized patients, over a nine-month period. Clinical isolates were examined by conventional susceptibility testing, using the disk-diffusion method and multiplex polymerase chain reaction to detect acquired carbapenemase genes. All of the isolates were completely resistant to TOB, SXT, IPM, MEM, CTX, CRO, FEP, CAZ, CIP, PTZ, PIP and were susceptible to colistin, but moderately susceptible TET (2.72%), AK (4.54%) and GEN (3.63%). The prevalence of bla-OXA-51like, bla-OXA-23like, bla-OXA-24like, bla-OXA-58like, blaSIM and blaSPM genes was 100%, 96.36%, 35.45%, 7.27%, 7.27% and 3.63%, respectively. bla-GIM and bla-VIM genes were not detected among the strains. Our results suggest that OXA-type carbapenemase genes plus class B ß-lactamases contribute to carbapenem resistance in the collected isolates. Therefore, quick identification of these resistant genes using molecular approaches is critical in limiting the spread of infections caused by A. baumannii. Drug administration correction of the physicians, based on antibiotic susceptibility testing and more knowledge on the nosocomial infection control policies as essential need.


Assuntos
Acinetobacter baumannii/genética , Proteínas de Bactérias/genética , beta-Lactamases/genética , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/enzimologia , Proteínas de Bactérias/classificação , Estudos Transversais , DNA Bacteriano/análise , Humanos , Testes de Sensibilidade Microbiana , beta-Lactamases/classificação
5.
Rep Biochem Mol Biol ; 7(1): 38-44, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30324116

RESUMO

Background: Pseudomonas aeruginosa, an opportunistic pathogen, is a common cause of healthcare-associated infections in immunocompromised individuals. The rapid emergence of multidrug-resistant strains has made P. aeruginosa infections progressively difficult to treat. In this study we evaluated the effect of a chimeric protein containing a P. aeruginosa PilQ fragment and the PilA disulfide loop (PilA-DSL) on the humoral immune response in BALB/c mice. Methods: A chimeric gene encoding an immunogenic region of PilQ and the PilA-DSL was synthesized. Following bacterial expression and purification, the protein was administered to mice and the humoral immune response analyzed. The resulting antibodies were analyzed using an opsonophagocytic killing assay. Results: The anti-recombinant protein antibody titer was significantly greater in immunized mice than in controls. In addition, antibody titers were significantly increased after booster immunizations, and the immunizations induced opsonophagocytosis of P. aeruginosa PAO1. Conclusion: These results suggest that an anti-adhesion-based vaccination may be effective in preventing P. aeruginosa infections. Further studies are needed to evaluate the abilities of such bivalent proteins to induce strong immune responses.

6.
Avicenna J Med Biotechnol ; 10(1): 34-40, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29296265

RESUMO

Background: Type 4 pili (T4P) is an important virulence factor of Pseudomonas aeruginosa (P. aeruginosa). T4P pass the outer membrane through a large oligomeric channel made of a single PilQ protein that is most highly conserved at their C-termini. To develop a functional vaccine that can be used in clinical application, the secretin domain of the PilQ (PilQ380-706) was produced as a recombinant protein. Methods: A 981 bp fragment of C-terminal of the pilQ secretin (pilQ1138-2118) from was designed into the prokaryotic expression vector pET28a. The presence of the pilQ1138-2118 gene in the recombinant construct (pET28a/pilQ) was assessed by double digestion and PCR. After transformation, expression of the recombinant PilQ was induced by addition of IPTG. The expressed recombinant protein was purified by a modified method using a HisTrap affinity column and finally confirmed by SDS-PAGE. The functional activities of the produced PilQ380-706 confirmed by Western blot analysis and twitching inhibition assay. Results: The PCR and enzymatic digestion results showed the presence of the pilQ1138-2118 gene in the construct. The protein electrophoresis showed that the molecular weight of the recombinant PilQ380-706 is approximately 37 kDa. The Western blot analysis confirmed the specificity of specific IgG against the PilQ380-706 protein. The PilQ380-706 protein showed high biological activity in all of these standard assays. Conclusion: Since, the PilQ380-706 protein plays an important role in the biogenesis of pili; and thus, the primary establishment of P. aeruginosa; it seems that it can be used as a candidate vaccine or an adjuvant in the future studies.

7.
PLoS One ; 12(8): e0183607, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28854219

RESUMO

INTRODUCTION: Emergence of vancomycin-intermediate Staphylococcus aureus (VISA) and vancomycin-resistant S. aureus (VRSA) strains has led to great concern in global public health in both developing and developed countries. This study investigated distribution and molecular characterization of VRSA strains in Tehran's hospitals using a combination of molecular typing methods. MATERIALS AND METHODS: A total of 1789 S. aureus isolates obtained between 2014 and 2017 and were characterized using antibiogram, SCCmec typing, spa typing, and multilocus-sequence typing. Resistance to vancomycin was determined by E-test method. After confirmation of the isolated VRSA strain, genetic analysis was performed by evaluating vanA and vanB genes presence.The presence of resistance (ermA, ermB, ermC, mupA, msrA, msrB, tetM, ant (4΄)-Ia, aac (6΄)-Ie/aph (2˝), aph (3΄)-IIIa) and toxin (etb, eta, pvl, tst) encoding genes was investigated by the polymerase chain reaction (PCR) technique. RESULTS: Of all S. aureus tested isolates, four isolates were confirmed as VRSA isolates and two isolates confirmed as VISA isolates. ST5- SCCmec II/t002 and ST239-SCCmec III/t037 strains had MIC values of 512µg/ml, ST239-SCCmec III/t037 and ST8-SCCmecIV/t008 strains had MIC values of 64µg/ml and ST22-SCCmec IV/t790 and ST239-SCCmec III/t030 strains had MIC values ≥ 8 µg/ml. pvl-encoding gene was confirmed in ST8-SCCmecIV/t008 and ST22-SCCmec IV/t790 strains. The isolates differed in the carriage of resistance and toxin encoding genes. CONCLUSIONS: The study revealed the existence of VRSA strains in capital of Iran, Tehran. To our knowledge, this is the first report of ST239-SCCmec III/t037 as VRSA strain. These findings support the need for future surveillance studies on VRSA strains to keep the emergence and transmission of these isolates to a minimum.


Assuntos
Infecção Hospitalar/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Resistência a Vancomicina/genética , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Técnicas de Tipagem Bacteriana/métodos , Carbono-Oxigênio Ligases/genética , Infecção Hospitalar/epidemiologia , Exotoxinas/genética , Genes Bacterianos/genética , Hospitais , Humanos , Irã (Geográfico)/epidemiologia , Leucocidinas/genética , Testes de Sensibilidade Microbiana/métodos , Proteínas Nucleares/genética , Proteínas de Ligação às Penicilinas/genética , Reação em Cadeia da Polimerase , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/fisiologia
8.
Acta Microbiol Immunol Hung ; 64(2): 143-150, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27981851

RESUMO

Acinetobacter baumannii is a major opportunistic pathogen in healthcare settings worldwide. In Iran, there are only few reports on the prevalence of aminoglycoside resistance genes among A. baumannii isolates. The aim of this study was to investigate the existence of aminoglycoside-modifying enzyme (AME) genes from A. baumannii strains collected at a university teaching hospital in Iran. One hundred A. baumannii strains were collected between 2014 and 2015 from hospitalized patients at Loghman Hakim Hospital, Tehran, Iran. Antimicrobial susceptibility was determined by disk diffusion method according to the Clinical and Laboratory Standards Institute recommendations. The DNA was extracted using a kit obtained from Bioneer Co. (Korea) and was used as a template for polymerase chain reaction. The most active antimicrobial agent against these strains was colistin. The rate of extended-spectrum cephalosporin resistance was 97%. The aadA1, aadB, aac(6')-Ib, and aac(3)-IIa genes were found in 85%, 77%, 72%, and 68% of A. baumannii isolates, respectively. This study showed a high prevalence rate of AME genes in A. baumannii. This prevalence rate has explained that further aminoglycoside resistance genes may have role in the resistance of clinical isolates of A. baumannii. Therefore, control and treatment of serious infections caused by this opportunistic pathogen should be given more consideration.


Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/enzimologia , Acinetobacter baumannii/isolamento & purificação , Aminoglicosídeos/metabolismo , Antibacterianos/metabolismo , Proteínas de Bactérias/genética , Acinetobacter baumannii/genética , Acinetobacter baumannii/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Criança , Pré-Escolar , Feminino , Humanos , Irã (Geográfico) , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Adulto Jovem
9.
Ther Adv Infect Dis ; 3(5): 133-138, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28149517

RESUMO

INTRODUCTION: Ethambutol (EMB) is an anti-mycobacterial agent that is most commonly used in combination with other anti-tuberculosis (TB) drugs in the treatment of TB. Studies have shown that primary resistance rates of Mycobacterium tuberculosis to EMB vary widely, that is, from 1% to as high as 14%. In this study, we aimed to determine the exact prevalence of primary EMB resistance among pulmonary TB cases. METHODS: Several databases, including Medline, Embase, and Iranian databases, were searched from March 2000 to January 2016 to identify studies addressing EMB-resistant TB in Iran. Comprehensive meta-analysis (V2.2, Biostat) software was used to analyze the data. RESULTS: Of the 112 records identified from the databases, 10 studies fulfilled the eligibility criteria. The pooled prevalence of primary EMB-resistant TB was estimated at 4.2% [95% confidence interval (CI) 1.8-9.0]. No evidence of publication bias was observed among the included studies (p = 0.4 for Begg rank correlation analysis; p = 0.2 for Egger weighted regression analysis). CONCLUSION: Results of systematic review and meta-analyses indicated that effective strategies to minimize the acquired drug resistance, to improve the drug susceptibility testing (DST) capability, and to control the transmission of resistance should be attached importance for control of TB in Iran.

10.
Rep Biochem Mol Biol ; 4(1): 50-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26989750

RESUMO

BACKGROUND: Neisseria meningitidis, a life-threatening human pathogen with the potential to cause large epidemics, can be isolated from the nasopharynx of 5-15% of adults. The aim of the current study was to evaluate biophysical and biochemical properties and immunological aspects of chimeric acyl-carrier protein-macrophage infectivity potentiator protein-type IV pilus biogenesis protein antigen (ACP-MIP-PilQ) from N. meningitidis serogroup B strain. METHODS: Biochemical properties and multiple alignments were predicted by appropriate web servers. Secondary molecular structures were predicted based on Chou and Fasman, Garnier-Osguthorpe-Robson, and Neural Network methods. Tertiary modeling elucidated conformational properties of the chimeric protein. Proteasome cleavage and transporter associated with antigen processing (TAP) binding sites, and T- and B-cell antigenic epitopes, were predicted using bioinformatic web servers. RESULTS: Based on our in silico and immunoinformatics analyses, the ACP-MIP-PilQ protein (AMP) can induce high-level cross-strain bactericidal activity. In addition, several immune proteasomal cleavage sites were detected. The 22 epitopes associated with MHC class I and class II (DR) alleles were confirmed in the AMP. Thirty linear B-cell epitopes as antigenic regions were predicted from the full-length protein. CONCLUSION: All predicted properties of the AMP indicate it could be a good candidate for further immunological in vitro and in vivo studies.

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