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1.
Microb Pathog ; 117: 43-48, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29432909

RESUMEN

Helicobacter Pylori (H. pylori) is a gram-negative bacteria infecting numerous people all over the world. It has been established that H. pylori play an important role in pathogenesis of gastritis, peptic ulcer and gastric cancer. Pathogenic features of this bacterium are mainly attributes to the existence of pathogenic islands (PAI) genes. The most known genes in these islands are cytotoxin-associated gene A (CagA) and vacuolating cytotoxin gene (VacA). Most studies demonstrated various frequency of CagA and VacA in patient with peptic ulcer or gastritis in different countries. This variation in CagA and VacA frequency may be due to the capability of this bacterium to be genetically versatile and can alter the expression of these genes with geographic diversity. Although H. pylori infection is not usually associated with any clinical symptoms, but sometimes leads to inflammation in gastrointestinal system and resulted in peptic ulcer and gastric cancer. In this regard, this review will illustrate the importance of Helicobacter pylori in pathogenesis of gastrointestinal disorders with focusing on CagA and VacA virulence factors.


Asunto(s)
Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Helicobacter pylori/genética , Helicobacter pylori/patogenicidad , Factores de Virulencia/genética , Antígenos Bacterianos/metabolismo , Proteínas Bacterianas/metabolismo , Bases de Datos Factuales , Gastritis/microbiología , Frecuencia de los Genes , Islas Genómicas/genética , Infecciones por Helicobacter/epidemiología , Infecciones por Helicobacter/inmunología , Infecciones por Helicobacter/microbiología , Interacciones Huésped-Patógeno/inmunología , Humanos , Úlcera Péptica/microbiología , Dominios y Motivos de Interacción de Proteínas , Neoplasias Gástricas/microbiología , Virulencia/genética
2.
Microb Pathog ; 113: 416-420, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29155011

RESUMEN

BACKGROUND: The cytotoxic effects on epithelial cells of the human are not observed in other strains of Klebsiella spp and are only observed in K. oxytoca strains. MTT assay was used to evaluate cytotoxic activity. In this study, colorimetric method was used to evaluate the cytotoxic effect of cytotoxin-producing isolates on Hep-2 cell line and determines the percentage of surviving cells. MATERIALS AND METHODS: In this study, we collected a total of 75 K. oxytoca strains isolate and we detected the production of toxins and their cytotoxic effects on HEp-2 cells. Colorimetric method such as MTT assay was used to evaluate the cytotoxic effect of cytotoxin-producing isolates on Hep-2 cell line and determines the percentage of surviving cells. RESULTS: Nine isolates had cytotoxic effects on HEp-2 cells. The results of MTT assay showed that the isolated strains were different from the control stain in terms of toxinogenicity and cytotoxic effects on HEp-2 cells at the studied dilutions (1:3, 1:6, 1:12, 1:24, 1:48, and 1:96). CONCLUSIONS: In the current study, Percentage of Hep-2 surviving cells exposed to 1:3, 1:6, 1:12, 1:24, 1:48, and 1:96 supernatant dilutions of cytotoxin-producing Klebsiella oxytoca isolates was different.


Asunto(s)
Línea Celular Tumoral/efectos de los fármacos , Citotoxinas/aislamiento & purificación , Citotoxinas/toxicidad , Klebsiella oxytoca/metabolismo , Sangre/microbiología , Supervivencia Celular/efectos de los fármacos , Heces/microbiología , Formazáns , Humanos , Irán , Infecciones por Klebsiella/microbiología , Klebsiella oxytoca/aislamiento & purificación , Esputo/microbiología , Sales de Tetrazolio , Orina/microbiología , Heridas y Lesiones/microbiología
3.
Microb Pathog ; 113: 1-4, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28970173

RESUMEN

BACKGROUND: Klebsiella oxytoca is an opportunistic pathogen which damages intestinal epithelium through producing cytotoxin tilivalline. This toxin plays a role in the pathogenesis of bacteria and is the main virulence factor which leads to antibiotic-associated hemorrhagic colitis progress. MATERIALS AND METHODS: In this study, we collected a total of 75 K. oxytoca strains isolated from the stool, urine, blood, wounds, and sputum and evaluated them in terms of the production of toxins; we detected their cytotoxic effects on HEp-2 cells. RESULTS: Of all the isolates, five K. oxytoca strains isolated from the stool cultures, two strains isolated from the blood cultures, one strains isolated from the wound cultures, and one strains isolated from the urine cultures had cytotoxic effects on HEp-2 cells. The strains isolated from sputum cultures had no cytotoxic effects on HEp-2 cells. CONCLUSIONS: In the current study, the majority of strains isolated from the stool of the patients included cytopathic effects on HEp-2 cells.


Asunto(s)
Benzodiazepinonas/metabolismo , Citotoxinas/metabolismo , Klebsiella oxytoca/aislamiento & purificación , Klebsiella oxytoca/patogenicidad , Línea Celular , Enterocolitis Seudomembranosa/microbiología , Heces/microbiología , Humanos , Infecciones por Klebsiella/diagnóstico , Infecciones por Klebsiella/microbiología , Klebsiella oxytoca/clasificación , Factores de Virulencia
4.
Microb Pathog ; 67-68: 48-54, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24583154

RESUMEN

We previously developed virus like particles of rotavirus (RV) with VP2, VP6, and VP7 proteins (VLP2/6/7) using stable High-five cell line. To evaluate the immunogenicity of our construct, we assessed the humoral and cytokine responses induced by VLP2/6/7 in BALB/c mice immunized intra-peritoneally and intra-rectally. Enzyme-linked immunosorbent assay (ELISA) and Relative quantitative (RQ) Real-time PCR were used to evaluate the antibody (IgG and IgA) levels in serum and mRNA levels of IL-6, IL-10 and IFN-γ in spleen cells, respectively. Our results showed that VLP2/6/7 is capable of intra-peritoneal (I.P.) and intra-rectal (I.R.) induction of serum IgG and IgA responses. IgA was detected in fecal samples of immunization groups by I.P. and I.R. routes. Interestingly, I.R. route induced higher IgA titer compared with I.P. route which was statistically significant. Moreover, mRNA levels of IL-6 and IFN-γ were significantly elevated in mice immunized intra-peritoneally with VLP2/6/7 compared to control group. As such, the mean change was 7.4 (P < 0.05) and 14.8 (P < 0.001) for IFN-γ and IL-6, respectively. Likewise, the same pattern was found when mice were immunized intra-rectally. Although elevated, the difference in the mean change for IL-10 was not statistically significant when compared to control group. Our findings indicated that VLPs constructed via a stable insect cell line are able to induce both humoral and cellular responses, a similar pattern as observed after immunization with live RVs.


Asunto(s)
Antígenos Virales/inmunología , Proteínas de la Cápside/inmunología , Infecciones por Rotavirus/inmunología , Rotavirus/inmunología , Vacunas Virales/inmunología , Administración Rectal , Animales , Anticuerpos Antivirales/inmunología , Antígenos Virales/administración & dosificación , Antígenos Virales/genética , Proteínas de la Cápside/administración & dosificación , Proteínas de la Cápside/genética , Femenino , Inmunización , Infusiones Parenterales , Interleucina-10/genética , Interleucina-10/inmunología , Interleucina-6/genética , Interleucina-6/inmunología , Ratones , Ratones Endogámicos BALB C , Rotavirus/genética , Infecciones por Rotavirus/genética , Infecciones por Rotavirus/virología , Vacunas Virales/administración & dosificación , Vacunas Virales/genética
5.
Bioeng Transl Med ; 7(1): e10254, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35111951

RESUMEN

Bacterial wound infection is one of the most common nosocomial infections. The unnecessary employment of antibiotics led to raising the growth of antibiotic-resistant bacteria. Accordingly, alternative armaments capable of accelerating wound healing along with bactericidal effects are urgently needed. Considering this, we fabricated chitosan (CS)/polyethylene oxide (PEO) nanofibers armed with antibacterial silver and zinc oxide nanoparticles. The nanocomposites exhibited a high antioxidant effect and antibacterial activity against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Besides, based on the results of the cell viability assays, the optimum concentration of ZnONPs and AgNPs in the nanofibrous mats is 0.2% w/v and 0.08% w/v respectively and had no cytotoxicity on fibroblast cells. The scaffold also showed good blood compatibility according to the effects of coagulation time. As well as significant fibroblast migration and proliferation on the wound margin, according to wound-healing assay. All in all, the developed biocompatible, antioxidant, and antibacterial Ag-ZnO NPs incorporated CS/PEO nanofibrous mats showed their potential as an effective wound dressing.

6.
J Cardiothorac Surg ; 17(1): 185, 2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-35986339

RESUMEN

Infective endocarditis (IE) is a severe disease that is still associated with high mortality despite recent advances in diagnosis and treatment. HACEK organisms (Haemophilus spp., Aggregatibacter actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae) are gram-negative bacteria that are part of the normal flora of the mouth and upper respiratory tract in humans. These organisms cause a wide range of infections, of which IE is one of the most notable. In order to control and prevent endocarditis caused by HACEK, measures such as oral hygiene and the use of prophylactic drugs should be used for people at risk, including people with underlying heart disease and people with artificial valves. This review is a summary of the main aspects of IE focusing on HACEK organisms.


Asunto(s)
Endocarditis Bacteriana , Endocarditis , Cardiopatías , Eikenella corrodens , Endocarditis/diagnóstico , Endocarditis/terapia , Endocarditis Bacteriana/microbiología , Haemophilus , Humanos
7.
FEMS Microbiol Lett ; 368(19)2021 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-34718541

RESUMEN

Drug resistance of methicillin-resistant Staphylococcus aureus, extended-spectrum beta-lactamases-producing Escherichia coli and Klebsiella pneumoniae and multidrug-resistant Acinetobacter baumannii are also cited as one of the most important causes of community and hospital acquired infections. Phage therapy can be used as a therapeutic method for the treatment of infections caused by these bacteria. The aim of this study was to isolate bacteriophages from municipal wastewater and assess their effects against drug resistant bacterial strains. The single agar layer technique was used to investigate the bacteriolytic effect of bacteriophages. Then, the double agar layer technique was used to observe phage plaques and the transmission electron microscopy was used to study the morphology of the bacteriophages. Transparent plaque formation in a double agar layer test of methicillin-resistant S. aureus and extended-spectrum beta-lactamases-producing E. coli and K. pneumoniae indicated the lysis of bacterial cells by isolated bacteriophages. No bacteriophage against A. baumannii was isolated from municipal wastewater. The morphology of these bacteriophages was also identified by electron microscopy. The results of this study showed that bacteriophages act specifically and due to the increasing level of antibiotic resistance, phage therapy as a new treatment can open a new horizon for the treatment of multidrug resistant bacteria.


Asunto(s)
Bacterias , Bacteriófagos , Acinetobacter baumannii/virología , Antibacterianos/farmacología , Bacterias/virología , Bacteriófagos/aislamiento & purificación , Bacteriófagos/fisiología , Escherichia coli/virología , Klebsiella pneumoniae/virología , Staphylococcus aureus Resistente a Meticilina/virología , Pruebas de Sensibilidad Microbiana , Aguas Residuales/microbiología
8.
AMB Express ; 11(1): 147, 2021 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-34731345

RESUMEN

The purpose of this study was to determine the mutations associated with clarithromycin resistance in Helicobacter pylori strains isolated from biopsy samples that were collected from the endoscopic ward of Shahrekord Hajar teaching Hospital and also to study the frequency of virulence factor and their correlation and pathological findings with clarithromycin resistance during the years 2019-2020. In this cross-sectional descriptive study, 152 patients with Helicobacter pylori infection were considered, and then, two common A2142G and A2143G mutations in the 23SrRNA gene associated with resistance were analyzed by Real-time PCR (Taq man). The presence of vacA, iceA1, iceA2, cagA, babA2, and oipA virulence genes was investigated by PCR and electrophoresis in 8% polyacrylamide gel. Then, data were analyzed using the relevant statistical tests. In this study, the frequency of Helicobacter pylori was 76% and the frequency of mutant isolates was 57.2%. The frequencies of A2142G and A2143G point mutations were 42.1% and 28.3%. There was a significant correlation among oipA, vacA, and iceA1 virulence factors, type of disease, chronic inflammatory score, and glandular atrophy with the antibiotic resistance to clarithromycin. There was no significant correlation between the age and sex of the patients with antibiotic resistance. According to the results of this study, it seems that the use of clarithromycin to combat this bacterium should be limited.

9.
Environ Sci Pollut Res Int ; 28(32): 43792-43802, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33837940

RESUMEN

The novel SARS-CoV-2 outbreak was declared as pandemic by the World Health Organization (WHO) on March 11, 2020. Understanding the airborne route of SARS-CoV-2 transmission is essential for infection prevention and control. In this study, a total of 107 indoor air samples (45 SARS-CoV-2, 62 bacteria, and fungi) were collected from different wards of the Hajar Hospital in Shahrekord, Iran. Simultaneously, bacterial and fungal samples were also collected from the ambient air of hospital yard. Overall, 6 positive air samples were detected in the infectious 1 and infectious 2 wards, intensive care unit (ICU), computed tomography (CT) scan, respiratory patients' clinic, and personal protective equipment (PPE) room. Also, airborne bacteria and fungi were simultaneously detected in the various wards of the hospital with concentrations ranging from 14 to 106 CFU m-3 and 18 to 141 CFU m-3, respectively. The highest mean concentrations of bacteria and fungi were observed in respiratory patients' clinics and ICU wards, respectively. Significant correlation (p < 0.05) was found between airborne bacterial concentration and the presence of SARS-CoV-2, while no significant correlation was found between fungi concentration and the virus presence. This study provided an additional evidence about the presence of SARS-CoV-2 in the indoor air of a hospital that admitted COVID-19 patients. Moreover, it was revealed that the monitoring of microbial quality of indoor air in such hospitals is very important, especially during the COVID-19 pandemic, for controlling the nosocomial infections.


Asunto(s)
Contaminación del Aire Interior , COVID-19 , Microbiología del Aire , Bacterias , Hongos , Hospitales , Humanos , Irán , Pandemias , SARS-CoV-2
10.
Curr Microbiol ; 61(6): 520-4, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20405128

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) is a nosocomial pathogen. Our main objective was to compare oxacillin disk test, oxacillin E-test, and oxacillin agar screen for detection of methicillin resistance in S. aureus, using real-time PCR for mecA as the "gold standard" comparison assay. 196 S. aureus isolates were identified out of 284 Staphylococcus isolates. These isolates were screened for MRSA with several methods: disk diffusion, agar screen (6.0 µg/ml), oxacillin E-test, and real-time PCR for detection of mecA gene. Of the 196 S. aureus isolates tested, 96 isolates (49%) were mecA-positive and 100 isolates (51%) mecA-negative. All methods tested had a statistically significant agreement with real-time PCR. E-test was 100% sensitive and specific for mecA presence. The sensitivity and specificity of oxacillin agar screen method were 98 and 99%, respectively and sensitivity and specificity of oxacillin disk diffusion method were 95 and 93%, respectively. In the present study, oxacillin E-test is proposed as the best phenotypic method. For economic reasons, the oxacillin agar screen method (6.0 µg/ml), which is suitable for the detection of MRSA, is recommended due to its accuracy and low cost.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Proteínas Bacterianas/genética , Humanos , Staphylococcus aureus Resistente a Meticilina/genética , Pruebas de Sensibilidad Microbiana , Proteínas de Unión a las Penicilinas , Sensibilidad y Especificidad , Infecciones Estafilocócicas/microbiología
11.
Heliyon ; 6(9): e04971, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33005792

RESUMEN

This study was conducted to identify patterns of cagA EPIYA motifs in H. pylori strains isolated from patients with gastrointestinal diseases in Hospitals of Shahrekord, and investigate the association between these biomarkers and clinical outcomes of gastrointestinal diseases due to H. pylori. In this study, 253 patients with gastrointestinal diseases were studied within 1395-1396. Histopathological investigations and urease test showed that 207 isolates were H. pylori-positive. Then, screening using a molecular technique, PCR, confirmed that 159 isolates had cagA. Finally, the pattern and prevalence of the motifs were determined by PCR and identified a number of motifs were sequenced. Results of this study showed that the pattern of motifs was as follows: ABC (140 isolates) (93/7%), ABCC (6 isolates) (3/77%), ABCCC (4 isolates) (2/5%), AB (7 isolates) (4/4%), AC (1 isolate) (0/6%), and BC (1 isolate) (0/6%). Sequencing results showed the presence of changed EPIYA motif in some isolates. CM motif sequence was also seen in all isolates. In this study, no significant association was seen between the prevalence rate of different patterns and clinical symptoms (p = 0.71). There is a slight association between the presence of ABC motifs and the type of digestive disorder (p = 0.056). Results indicated that ABC was the most frequently seen pattern however, in such that positive cases of ABC motifs were more common in gastritis. All isolates had kinase phosphorylation region, and the observed pattern in this region was a generally western type (ABC).

12.
J Biomed Mater Res B Appl Biomater ; 108(8): 3084-3098, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32459395

RESUMEN

Dual-pump electrospinning of antibacterial N-decyl-N, N-dimethyl-1-decanaminium-chloride (DDAC)-loaded polycaprolactone (PCL) nanofibers, and chitosan (CS)/polyethylene-oxide (PEO)-based wound dressings with hydrophilic and hydrophobic properties to eliminate and absorb pathogenic bacteria from wound surface besides antibacterial action and to support wound healing and accelerate its process. Physicochemical properties of the prepared nanofibrous mat as well as antibacterial, cytotoxicity, and cell compatibility were studied. The full-thickness excisional wound healing properties up to 3 weeks using hematoxylin and eosin and Masson-trichrome staining were investigated. Addition of DDAC to CS/PEO-PCL mats decreased the diameter of the nanofibers, which is a crucial property for wound healing as large surface area per volume ratio of nanofibers, in addition to proper cell adhesion, increases loading of DDAC in mats and leads to increased cell viability and eliminating Gram-positive bacteria at in vitro studies. In vivo studies showed DDAC-loaded CS/PEO-PCL mats increased epithelialization and angiogenesis and decreased the inflammation according to histological results. We demonstrated that hydrophobic PCL/DDAC mats, besides antibacterial properties of DDAC, absorbed and eliminated the hydrophobic pathological microorganisms, whereas the hydrophilic nanofibers consisted of CS/PEO, increased the cell adhesion and proliferation due to positive charge of CS. Finally, we were able to increase the wound healing quality by using multifunctional wound dressing. CS/PEO-PCL containing 8 wt % of DDAC nanofibrous mats is promising as a wound dressing for wound management due to the favorable interactions between the pathogenic bacteria and PCL/CS-based wound dressing.


Asunto(s)
Vendajes , Quitosano , Poliésteres , Cicatrización de Heridas/efectos de los fármacos , Animales , Antibacterianos/farmacología , Adhesión Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular , Células Cultivadas , Epitelio/efectos de los fármacos , Epitelio/crecimiento & desarrollo , Bacterias Grampositivas/efectos de los fármacos , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Ratones , Ratones Endogámicos BALB C , Nanofibras , Neovascularización Fisiológica/efectos de los fármacos , Porosidad , Heridas y Lesiones/tratamiento farmacológico , Heridas y Lesiones/microbiología , Heridas y Lesiones/terapia
13.
BMC Res Notes ; 12(1): 597, 2019 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-31533853

RESUMEN

OBJECTIVE: Acinetobacter baumanii is a pathogenic bacterium that is the cause of many nosocomial infections. This study aimed to determine metallo-ß-lactamases (MBL) produced by the A. baumanii isolates obtained from clinical samples in Shahrekord, southwest Iran. RESULTS: A total of 100 A. baumanii were isolated from 250 clinical samples between June 2013 and June 2014. Then, the isolates were identified by biochemical tests, and MBL screening was conducted by the phenotypic tests modified Hodge, EDTA-disk synergy (EDS), combined disk (CD) and AmpC disc after antibiotic sensitivity test. Using PCR technique the bla genes were detected. Eighty-five (85%) isolates were resistant to meropenem and imipenem. Phenotypic tests showed that out of the 100 isolates, 46, 59, 50, 65 and 65 isolates were positive: AmpC disk, CD, EDS, Modified Hodge and E-test MBL respectively. Gene detection by PCR showed that 23 isolates carried the VIM-1 gene and only three isolates carried the IMP-1 gene. The prevalence of metallo-ß-lactamases isolates containing A. baumanii is increasing. Furthermore, the coexistence of various carbapenemases is dominantly act as a major problem. Continuous monitoring of the infections related to these bacteria should be considered to plan an alternative and new therapeutic strategies.


Asunto(s)
Acinetobacter baumannii/enzimología , Proteínas Bacterianas/metabolismo , Metaloproteínas/metabolismo , beta-Lactamasas/metabolismo , Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/genética , Acinetobacter baumannii/fisiología , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/farmacología , Infección Hospitalaria/microbiología , Farmacorresistencia Bacteriana Múltiple , Genotipo , Imipenem/farmacología , Irán , Meropenem/farmacología , Metaloproteínas/genética , Metaloproteínas/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Fenotipo , beta-Lactamasas/genética , beta-Lactamasas/aislamiento & purificación , beta-Lactamasas/farmacología
14.
Microbiol Res ; 218: 49-57, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30454658

RESUMEN

Helicobacter pylori (H. pylori) is a bacterial pathogen that resides in more than half of the human population and has co-evolved with humans for more than 58,000 years. This bacterium is orally transmitted during childhood and is a key cause of chronic gastritis, peptic ulcers and two malignant cancers including MALT (mucosa-associated lymphoid tissue) lymphoma and adenocarcinoma. Despite the strong innate and adaptive immune responses, H. pylori has a long-term survival in the gastric mucosa. In addition to the virulence factors, survival of H. pylori is strongly influenced by the ability of bacteria to escape, disrupt and manipulate the host immune system. This bacterium can escape from recognition by innate immune receptors via altering its surface molecules. Moreover, H. pylori subverts adaptive immune response by modulation of effector T cell. In this review, we discuss the immune-pathogenicity of H. pylori by focusing on its ability to manipulate the innate and acquired immune responses to increase its survival in the gastric mucosa, leading up to gastrointestinal disorders. We also highlight the mechanisms that resulted to the persistence of H. pylori in gastric mucosa.


Asunto(s)
Mucosa Gástrica/microbiología , Helicobacter pylori/inmunología , Interacciones Huésped-Patógeno/inmunología , Evasión Inmune/inmunología , Inmunidad Adaptativa/inmunología , Enfermedades Gastrointestinales/microbiología , Helicobacter pylori/patogenicidad , Humanos , Inmunidad Innata/inmunología , Factores de Virulencia
15.
Int Immunopharmacol ; 66: 242-250, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30500621

RESUMEN

Experiencing psychosocial adversities in early life such as maternal separation (MS) increases the risk of psychiatric disorders. Immune-inflammatory responses have imperative roles in the pathophysiology of psychiatric disorders. MS relatively changes the composition of intestinal microbiota leading to an overactivation of the hypothalamic-pituitary-adrenal (HPA) axis, and subsequently increases the corticosterone level. In this study, we aimed to evaluate the role of corticosterone in behavioral changes and microbiota modifications in a mouse model of MS afflicted neuroinflammatory response in the hippocampus. For this purpose, 180 min of MS stress was applied to mice at postnatal day (PND) 2-14 followed by behavioral tests including forced swimming test (FST), splash test, open field test (OFT) and elevated plus maze (EPM) at PND 50-52. For evaluating the role of corticosterone, mice were subjected to adrenalectomy. Using real-time RT-PCR, the expression of inflammatory genes was determined in the hippocampus and colon tissues. We found that MS provoked depressive- and anxiety-like behaviors in adult male mice. In addition, MS was able to active a neuroimmune response in the hippocampus, motivate inflammation and histopathologic changes in the colon tissue and modify the composition of gut microbiota as well. Interestingly, our findings showed that adrenalectomy (decline in the corticosterone level), could modulate the above-mentioned negative effects of MS. In conclusion, our results demonstrated that overactivation of HPA axis and the subsequent increased level of corticosterone could act, possibly, as the deleterious effects of MS on behavior, microbiota composition changes and activation of neuroimmune response.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/metabolismo , Corticosterona/metabolismo , Microbioma Gastrointestinal/fisiología , Hipocampo/fisiología , Inflamación/metabolismo , Estrés Fisiológico/fisiología , Animales , Animales Recién Nacidos , Trastorno por Déficit de Atención con Hiperactividad/psicología , Conducta Animal , Modelos Animales de Enfermedad , Femenino , Masculino , Privación Materna , Ratones , Ratones Endogámicos , Neuroinmunomodulación , Sistema Hipófiso-Suprarrenal , Problema de Conducta
16.
Mol Immunol ; 104: 128-138, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30448609

RESUMEN

Leptospirosis is known as a zoonotic disease of global importance originated from infection with the spirochete bacterium Leptospira. Although several leptospirosis vaccines have been tested, the vaccination is relatively unsuccessful in clinical application despite decades of research. Therefore, this study was conducted to construct a novel multi-epitope based vaccine against leptospirosis by using Hap1, LigA, LAg42, SphH and HSP58 antigens. T cell and IFN gamma epitopes were predicted from these antigens. In addition, to induce strong CD4+ helper T lymphocytes (HTLs) responses, Pan HLA DR-binding epitope (PADRE) and helper epitopes selected from Tetanus toxin fragment C (TTFrC) were applied. Moreover, for boosting immune response, Heparin-Binding Hemagglutinin (HBHA), a novel TLR4 agonist was added to the construct as an adjuvant. Finally, selected epitopes were linked together using EAAAK, GPGPG, AAY and HEYGAEALERAG linkers. Based on the predicted epitopes, a multi-epitope vaccine was construct with 490 amino acids. Physico-chemical properties, secondary and tertiary structures, stability, intrinsic protein disorder, solubility, and allergenicity of this vaccine construct were assessed by applying immunoinformatics analyses. A soluble, and non-allergic protein with a molecular weight of 53.476 kDa was obtained. Further analyses validated the stability of the chimeric protein and the predicted epitopes in the chimeric vaccine indicated strong potential to induce B-cell and T-cell mediated immune response. Therefore, immunoinformatics analysis showed that the modeled multi-epitope vaccine can properly stimulate the both T and B cells immune responses and could potentially be used for prophylactic or therapeutic usages.


Asunto(s)
Antígenos Bacterianos/inmunología , Vacunas Bacterianas/inmunología , Biología Computacional , Mapeo Epitopo , Epítopos de Linfocito T/inmunología , Leptospira/inmunología , Leptospirosis/inmunología , Antígenos Bacterianos/genética , Linfocitos B/inmunología , Vacunas Bacterianas/genética , Epítopos de Linfocito T/genética , Humanos , Inmunidad Celular , Leptospira/genética , Leptospirosis/genética , Leptospirosis/prevención & control , Dominios Proteicos , Linfocitos T/inmunología , Receptor Toll-Like 4/agonistas , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/inmunología
17.
Osong Public Health Res Perspect ; 7(5): 301-306, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27812488

RESUMEN

OBJECTIVES: Production of carbapenemase, especially Klebsiella pneumoniae carbapenemases (KPC), is one of the antibiotic resistance mechanisms of Enterobacteriaceae such as Klebsiella oxytoca. This study aimed to investigate and identify KPC-producing K. oxytoca isolates using molecular and phenotypic methods. METHODS: A total of 75 isolates of K. oxytoca were isolated from various clinical samples, and were verified as K. oxytoca after performing standard microbiological tests and using a polymerase chain reaction (PCR) method. An antibiotic susceptibility test was performed using a disc diffusion method according to the Clinical and Laboratory Standards Institute guidelines. CHROMagar KPC chromogenic culture media was used to examine and confirm the production of the carbapenemase enzyme in K. oxytoca isolates; in addition, PCR was used to evaluate the presence of blaKPC gene in K. oxytoca strains. RESULTS: Of a total of 75 K. oxytoca isolates, one multidrug resistant strain was isolated from the urine of a hospitalized woman. This strain was examined to assess its ability to produce carbapenemase enzyme; it produced a colony with a blue metallic color on the CHROMagar KPC chromogenic culture media. In addition, the blaKPC gene was confirmed by PCR. After sequencing, it was confirmed and deposited in GenBank. CONCLUSION: To date, many cases of KPC-producing Enterobacteriaceae, in particular K. pneumoniae, have been reported in different countries; there are also some reports on the identification of KPC-producing K. oxytoca. Therefore, to prevent the outbreak of nosocomial infections, the early detection, control, and prevention of the spread of these strains are of great importance.

18.
Jundishapur J Microbiol ; 9(1): e28291, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27099685

RESUMEN

BACKGROUND: A diversity of virulence factors work together to create the pathogenicity of Staphylococcus aureus. These factors include cell surface components that promote adherence to surfaces as well as exoproteins such as Panton-Valentine leukocidin (PVL), encoded by the luk-PV genes, that invade or bypass the immune system and are toxic to the host, thereby enhancing the severity of infections caused by methicillin-resistant Staphylococcus aureus (MRSA). OBJECTIVES: The aim of this study was to determine the frequency of PVL-positive MRSA strains by real-time PCR and their antibiotic susceptibility patterns by phenotypic test. MATERIALS AND METHODS: In total, 284 Staphylococcus isolates, identified by phenotypic methods from clinical samples of Shahrekord University Hospitals, Shahrekord, Iran, were tested for nuc, mecA, and PVL genes by TaqMan real-time PCR. The antibiotic susceptibility patterns of PVL-containing MRSA strains were determined via the disk diffusion method. RESULTS: In total, 196 isolates (69%) were nuc positive (i.e., S. aureus); of those isolates, 96 (49%) were mecA positive (MRSA). Eighteen (18.8%) of the 96 MRSA positive and 3 (3%) of the 100 methicillin-susceptible Staphylococcus aureus (MSSA) strains were PVL positive. PVL-positive MRSA strains were mostly recovered from tracheal specimens. Eight PVL-positive MRSA strains were resistant to all the tested antibiotics except vancomycin. A significant correlation (P = 0.001) was found between the mecA positivity and the presence of luk-PV genes. CONCLUSIONS: Community acquired (CA)-MRSA is becoming a public health concern in many parts of the world, including Asian countries. The variable prevalence of luk-PV-positive MRSA isolates in different regions and their rather high frequency in pneumonia necessitate the application of rapid diagnostic methods such as real-time PCR to improve treatment effectiveness.

19.
Pediatr Infect Dis J ; 33(2): 218-20, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23989109

RESUMEN

Viruses are prominent causative agents of acute gastroenteritis in children <5 years of age per year. In the present review, all viral gastroenteritis studies in Iran were assessed, and the mean prevalences of rotaviruses, noroviruses, enteric adenoviruses, sapoviruses and astroviruses associated with acute gastroenteritis were 39.9%, 6%, 5.7%, 4.2% and 2.7%, respectively. In 2 studies, human bocavirus and human parechovirus were detected in 21.8% and 23.7% of children with acute gastroenteritis, respectively.


Asunto(s)
Gastroenteritis/epidemiología , Gastroenteritis/virología , Virosis/epidemiología , Virosis/virología , Preescolar , Humanos , Lactante , Irán/epidemiología , Prevalencia
20.
Adv Biomed Res ; 2: 57, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24223372

RESUMEN

BACKGROUND: One of the most common causes of vaginitis is candidiasis. The aim of this study is to compare the effect of honey and miconazole against Candida albicans, in vitro. MATERIALS AND METHODS: The different W/V concentrations of honey were prepared at 20, 40, 60, 80, and 95% and different dilutions of miconazole were prepared in 0.05, 5, and 50 µg/ml. A microdilution of 100/000 cells per ml of a two-day old culture of Candida albicans was prepared in normal saline, after culturing the strain of PTCC 5027 in RPMI 1640 medium. Ten microliters of this dilution was added to 1 ml of the RPMI 1640 medium containing different concentrations of honey and to 1 ml of the RPMI 1640 medium containing different dilutions of miconazole. The cultures were incubated at 35°C for 12, 24, and 48 hours. RESULTS: The growth rate of Candida albicans was determined in the cultures. The results indicated that the honey prevented the growth of C. albicans greatly only at an 80% concentration, whereas, miconazole inhibited it completely. CONCLUSIONS: As Candida albicans is a normal vaginal flora, the inhibitory effect of honey without the fungicide effect is a very good trend in the treatment of vaginal candidiasis.

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