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INTRODUCTION: Infections caused by Stenotrophomonas maltophilia are clinically important due to its intrinsic resistance to a broad range of antibiotics. Therefore, selecting the most appropriate antibiotic to treat S. maltophilia infection is a major challenge. AIM: The current meta-analysis aimed to investigate the global prevalence of antibiotic resistance among S. maltophilia isolates to the develop more effective therapeutic strategies. METHOD: A systematic literature search was performed using the appropriate search syntax after searching Pubmed, Embase, Web of Science and Scopus databases (May 2023). Statistical analysis was performed using Pooled and the random effects model in R and the metafor package. A total of 11,438 articles were retrieved. After a thorough evaluation, 289 studies were finally eligible for inclusion in this systematic review and meta-analysis. RESULT: Present analysis indicated that the highest incidences of resistance were associated with doripenem (97%), cefoxitin (96%), imipenem and cefuroxime (95%), ampicillin (94%), ceftriaxone (92%), aztreonam (91%) and meropenem (90%) which resistance to Carbapenems is intrinsic. The lowest resistance rates were documented for minocycline (3%), cefiderocol (4%). The global resistance rate to TMP-SMX remained constant in two periods before and after 2010 (14.4% vs. 14.6%). A significant increase in resistance to tigecycline and ceftolozane/tazobactam was observed before and after 2010. CONCLUSIONS: Minocycline and cefiderocol can be considered the preferred treatment options due to low resistance rates, although regional differences in resistance rates to other antibiotics should be considered. The low global prevalence of resistance to TMP-SMX as a first-line treatment for S. maltophilia suggests that it remains an effective treatment option.
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Antibacterianos , Farmacorresistencia Bacteriana , Infecciones por Bacterias Gramnegativas , Stenotrophomonas maltophilia , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/epidemiología , Pruebas de Sensibilidad Microbiana , Stenotrophomonas maltophilia/efectos de los fármacos , Stenotrophomonas maltophilia/aislamiento & purificaciónRESUMEN
BACKGROUND: Colorectal cancer is one of the widespread and lethal types of malignancies. Recently, antineoplastic attributes of probiotics have attracted lots of attention. Here, we investigated anti-proliferative potential of the non-pathogenic strains Lactobacillus plantarum ATCC 14,917 and Lactobacillus rhamnosus ATCC 7469 on human colorectal adenocarcinoma-originated Caco-2 cells. METHODS AND RESULTS: Caco-2 and HUVEC control cells were treated with ethyl acetate extracts of the two Lactobacillus strains to assess cell viability by MTT assay. Annexin/PI staining flow cytometry, and caspase-3, -8 and - 9 activity assays were performed to determine the type of cell death induced in extract-treated cells. Expression levels of apoptosis-related genes were evaluated by RT-PCR. Extracts from both L. plantarum and L. rhamnosus specifically targeted the Caco-2 cells and not HUVEC controls, and significantly affected the viability of the colon cancer cell line in a time- and dose-dependent manner. This effect was shown to occur through activation of the intrinsic apoptosis pathway, as indicated by the increased caspase-3 and - 9 activities. While there are limited and conflicting data about the mechanisms underlying the specific antineoplastic attributes of Lactobacillus strains, we clarified the overall induced mechanism. The Lactobacillus extracts specifically down-regulated the expression of the anti-apoptotic bcl-2 and bcl-xl, and simultaneously up-regulated the pro-apoptotic bak, bad, and bax genes in treated Caco-2 cells. CONCLUSIONS: Ethyl acetate extracts of L. plantarum and L. rhamnosus strains could be considered as targeted anti-cancer treatments specifically inducing the intrinsic apoptosis pathway in colorectal tumor cells.
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Antineoplásicos , Neoplasias del Colon , Neoplasias Colorrectales , Lacticaseibacillus rhamnosus , Lactobacillus plantarum , Probióticos , Humanos , Células CACO-2 , Caspasa 3/genética , Caspasa 3/metabolismo , Neoplasias del Colon/tratamiento farmacológico , Lactobacillus , Apoptosis , Antineoplásicos/farmacología , Probióticos/farmacologíaRESUMEN
INTRODUCTION: Coronavirus disease 2019 (COVID-19) and acquired immune deficiency syndrome (AIDS) are two viral diseases for which there are currently no definitive treatments. Nowadays, because of the health system's focus on the COVID-19 epidemic, the control of human immunodeficiency virus (HIV) has received less attention. In this review, we will discuss the characteristics of COVID-19 in HIV-positive patients. MATERIAL AND METHODS: Using the PRISMA guideline, the databases of Scopus, PubMed, and Web of Science were searched systematically from January 1, 2019 to February 24, 2021. The following keywords were used: "Human Immunodeficiency Virus," "acquired immune deficiency syndrome," "HIV," "AIDS," "COVID-19," "severe acute respiratory syndrome coronavirus 2," "novel coronavirus," "SARS-CoV-2," "nCoV disease," "SARS2," and "2019-nCoV disease." RESULTS: Twenty-one percent of studies were conducted in the USA (n = 13), 16% in China (n = 10), and 13% in Italy (n = 8), respectively. The majority of the patients were men (74.3%). Tenofovir disoproxil fumarate was used in 47.4% of patients, emtricitabine in 58.4%, and lamivudine in 34.8% to treat HIV. Symptoms of HIV patients with COVID-19 included coughing (81.3%), fever (62.8%), and dyspnea (60%). Hydroxychloroquine (39.34%) and azithromycin (36.58%) were the common treatment options for COVID-19. The total death rate in HIV-positive patients with COVID-19 was about 9%. CONCLUSION: In the current systematic review, we demonstrated that HIV-positive patients co-infected with COVID-19 have high comorbidity of hypertension and diabetes mellitus. HIV/COVID-19 co-infection might have negatively influenced the HIV treatment and diagnosis, which indicates the need to regularly screen HIV patients in the COVID-19 pandemic.
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Síndrome de Inmunodeficiencia Adquirida , COVID-19 , Infecciones por VIH , COVID-19/complicaciones , COVID-19/epidemiología , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Masculino , Pandemias , SARS-CoV-2RESUMEN
INTRODUCTION: Empyema is one of the important causes of pediatric hospital admissions. AIM: In this study, we had investigated the frequency rates of S aureus, S pneumoniae, H influenzae, and P aeruginosa using PCR and bacterial culture among children suffering from empyema in Ahvaz city, Iran. METHODS: This was a descriptive study conducted on the patients hospitalized in ICUs of two teaching Hospitals of Ahvaz, Iran, between March and September 2018 on 105 pleural fluid (PF) samples of the children less than 16 years of age with the diagnosis of empyema thoracis. These specimens were inoculated on the bacterial culture media and identified using biochemical characteristics. Then, the existence of the four pathogens mentioned above was evaluated using PCR method. RESULT: In this study, these bacteria agents were identified in 81 (77.14%) and 30 (28.57%) cases using the PCR assay and bacterial culture, respectively. Moreover, the PCR assay identified the infectious agents in 51 (68%) of PFs where the culture method failed. S pneumoniae (63 cases) was recognized as the most common pathogen, followed by P aeruginosa(19 cases), S aureus(15 cases), and H influenzae (9 cases) using the bacterial culture and PCR. Co-infections were detected in 21 samples (20%) using PCR and one sample using the bacterial culture (P aeruginosa and S pneumoniae). CONCLUSION: In this study, we found the higher frequencies of these microorganisms using PCR than culture. In addition, we showed that PCR was a sensitive and accurate method that unaffected by antibiotic therapy and could detect well co-infections.
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Empiema Pleural/microbiología , Infecciones por Haemophilus/microbiología , Infecciones Neumocócicas/microbiología , Infecciones por Pseudomonas/microbiología , Infecciones Estafilocócicas/microbiología , Adolescente , Técnicas Bacteriológicas , Niño , Preescolar , Coinfección/epidemiología , Coinfección/microbiología , Empiema Pleural/tratamiento farmacológico , Empiema Pleural/epidemiología , Femenino , Infecciones por Haemophilus/tratamiento farmacológico , Infecciones por Haemophilus/epidemiología , Haemophilus influenzae/genética , Humanos , Lactante , Irán/epidemiología , Masculino , Infecciones Neumocócicas/tratamiento farmacológico , Infecciones Neumocócicas/epidemiología , Reacción en Cadena de la Polimerasa , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/epidemiología , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/patogenicidad , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/genética , Streptococcus pneumoniae/genéticaRESUMEN
The emergence of 16S rRNA methylase genes encoded on plasmids confers high-level aminoglycoside resistance (HLAR). This study aimed to investigate the prevalence of 16S rRNA methylases among Enterobacter cloacae strains isolated from an Ahvaz teaching hospital, Iran. A total of 68 E. cloacae clinical strains were collected between November 2017 and September 2018. The MICs of aminoglycosides were assessed using the agar dilution method. The presence of 16S rRNA methylase genes, including armA, rmtA to rmtH, and nmpA was evaluated by PCR. The transferability of 16S rRNA methylase-harboring plasmids was evaluated by conjugation assay. The genetic diversity of all isolates was evaluated by ERIC-PCR. The armA and rmtB genes were the only 16S rRNA methylase genes detected in this study (29 out of 68 isolates; 42.64%). The transferability by conjugation was observed in 23 rmtB or/and armA positive donors. HLAR phenotype was in 33 of 68 strains. Ten clonal types were obtained by ERIC-PCR and significant associations (p < 0.05) were between the clone types and aminoglycoside susceptibility, as well as with profile of the 16S rRNA methylase genes. In conclusion, both horizontal transfer and clonal spread are responsible for dissemination of the rmtB and armA genes among E. cloacae strains.
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Aminoglicósidos/farmacología , Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Enterobacter cloacae/efectos de los fármacos , Enterobacter cloacae/aislamiento & purificación , Infecciones por Enterobacteriaceae/microbiología , ARNt Metiltransferasas/análisis , Conjugación Genética , Enterobacter cloacae/clasificación , Enterobacter cloacae/genética , Infecciones por Enterobacteriaceae/epidemiología , Variación Genética , Genotipo , Técnicas de Genotipaje , Hospitales de Enseñanza , Humanos , Irán/epidemiología , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Plásmidos/análisis , Reacción en Cadena de la Polimerasa , Prevalencia , ARNt Metiltransferasas/genéticaRESUMEN
Aminoglycosides are widely recommended for treatment of Acinetobacter baumannii infections in combination with ß-lactams or quinolones. This cross-sectional study was aimed to investigate the coexistence of aminoglycoside modifying enzyme (AME) genes among A. baumannii isolates from clinical samples in Ahvaz, Iran. A total of 85 clinical A. baumannii isolates typed by ERIC-PCR were investigated for the presence of AME genes, including ant(3â³)-Ia, aac(6')-Ib, aac(3')-Ia, ant(2â³)-Ia, and aph(3')-VIa by PCR. The resistance rates to aminoglycoside agents were evaluated by disk diffusion. In this study, 84 out of 85 A. baumannii isolates were resistant to at least one of the aminoglycosides and harbored at least one AME gene. The most common gene encoding AMEs was aph (3')VIa, followed by aac(3')-Ia, ant(3â³)-Ia, ant (2â³)-Ia, and aac(6')-Ib. The aminoglycoside-resistant genotypes were completely matched to resistant phenotypes to each one of the aminoglycoside agents. There was a clear association between AME gene types and the phenotype of resistance to aminoglycosides with their ERIC-PCR types. Our findings highlight the coexistence of AME genes and clonal dissemination of multiresistant A. baumannii in hospital setting.
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Acinetobacter baumannii/enzimología , Acinetobacter baumannii/genética , Aminoglicósidos/farmacología , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana/genética , Acinetobacter baumannii/efectos de los fármacos , Aminoglicósidos/metabolismo , Estudios Transversales , Genotipo , Humanos , Irán , Pruebas de Sensibilidad Microbiana , Fenotipo , ARN Ribosómico 16S/genéticaRESUMEN
INTRODUCTION: The development of colistin resistance in Acinetobacter baumannii during treatment has been identified in certain patients, often leading to prolonged or recurrent infections. As colistin, is the last line of therapy for A. baumannii infections that are resistant to almost all other antibiotics, colistin-resistant A. baumannii strains currently represent a significant public health threat, particularly in healthcare settings where there is significant selective pressure. AIM: The aim of this study was to comprehensively determine the prevalence of colistin resistance in A. baumannii from clinical samples. Regional differences in these rates were also investigated using subgroup analyses. METHOD: The comprehensive search was conducted using "Acinetobacter baumannii", "Colistin resistant" and all relevant keywords. A systematic literature search was performed after searching in PubMed, Embase, Web of Science, and Scopus databases up to April 25, 2023. Statistical analysis was performed using Stata software version 17 and sources of heterogeneity were evaluated using I2. The potential for publication bias was explored using Egger's tests. A total of 30,307 articles were retrieved. After a thorough evaluation, 734 studies were finally eligible for inclusion in the present systematic review and meta-analysis. RESULT: According to the results, the prevalence of resistance to colistin among A. baumannii isolates was 4% (95% CI 3-5%), which has increased significantly from 2% before 2011 to 5% after 2012. South America had the highest resistance rate to this antibiotic. The broth microdilution method had the highest level of resistance, while the agar dilution showed the lowest level. CONCLUSIONS: This meta-analysis found a low prevalence of colistin resistance among A. baumannii isolates responsible for infections worldwide from 2000 to 2023. However, there is a high prevalence of colistin-resistant isolates in certain countries. This implies an urgent public health threat, as colistin is one of the last antibiotics available for the treatment of infections caused by XDR strains of A. baumannii.
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Infecciones por Acinetobacter , Acinetobacter baumannii , Antibacterianos , Colistina , Farmacorresistencia Bacteriana , Acinetobacter baumannii/efectos de los fármacos , Colistina/farmacología , Humanos , Infecciones por Acinetobacter/epidemiología , Infecciones por Acinetobacter/microbiología , Antibacterianos/farmacología , Prevalencia , Pruebas de Sensibilidad MicrobianaRESUMEN
Ebolavirus (EBOV) is a virulent pathogen that causes Ebola virus disease (EVD), which is a life-threatening human condition with a fatality rate of up to 90%. Since the first outbreak in Africa in 1976, several outbreaks and epidemics of EBOV have occurred across the globe. While EVD is recognized as a serious threat to human health and outbreaks occur almost every year, the treatment options for the disease are limited. In designing therapeutic strategies against EBOV infection, viral structural proteins, such as glycoprotein (GP), could be an excellent target for neutralizing the virus. According to the latest research, GP-specific antibodies are the most efficient post-exposure treatments for EVD. Ansuvimab-zykl, i.e., mAb114 (Ebanga™), is a recent FDA-approved human immunoglobulin monoclonal antibody targeting EBOV GP. This review provides a brief overview of the pharmacological effects and safety profile of ansuvimab in clinical trials and provides insights into the precise mechanism of this new drug for treating EVD.
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Background: The oral cavity can act as an extra gastric reservoir for H. pylori, and the presence of the bacteria in the oral cavity is associated with a higher risk of dental caries development. This study aimed to determine the genotype and evaluate the association between the presence of H. pylori in dental plaque and gastric biopsy specimens in dyspeptic patients in Ahvaz, Southwest Iran. Methods: In this study, 106 patients with recruited dyspeptic complaints were selected, and from each patient, two gastric antral biopsy specimens and two dental plagues were examined. The presence of H. pylori was identified by the rapid urease test (RUT) and the amplification of ureAB and 16S rRNA genes. Also, to verify a hypothetical mouth-to-stomach infection route, the enzymatic digestions of three genes of cagA, vacA, and ureAB in H. pylori strains isolated from dental plaques and stomach samples were compared for each same case. Results: H. pylori was found in the stomach of 52.8% (56/106) and the dental plaques of 17.9% (19/106) of the studied cases. On the other hand, H. pylori was recognized in the stomach of all 19 cases with oral colonization. Following a combination of restriction fragment lengths 21 polymorphism (RFLP) patterns of these three known genes on stomach and dental plague samples, 14 and 11 unique patterns were seen, respectively. However, for all H. pylori-positive cases (19), the comparison of RLFP patterns of these genes in dental plaque and gastric biopsy specimens was different for the same case. Conclusions: In this study, it seems that there is no significant association between the presence of H. pylori in dental plaque and the stomach of the same case.
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Background and Aims: The present study aimed to review probiotics' clinical efficacy in preventing infectious diseases among hospitalized patients in ICU and non-ICU wards. Methods: A search of Medline, EMBASE, The Cochrane Library, Science Direct, Open Grey, and Google Scholar was conducted for eligible publications from 2002 to 2020 following the requirements outlined in the PRISMA guideline. The search strategy was based on the combination of the following terms: "probiotics," "prebiotics," "synbiotics," and "cross-infection." The logical operators "AND" (or the equivalent operator for the databases) and "OR" (e.g., probiotics OR prebiotics OR synbiotics) were used. Results: The results indicated that the probiotic consumption caused a significant reduction in antibiotic-associated diarrhea (AAD) and Clostridioides difficile infection (CDI) in 2/8 randomized clinical trials (RCTs) investigating AAD/CDI. Also, 5/12 clinical trials highlighted the considerable effects of probiotics on the reduction or prevention of ventilator associated pneumoniae (VAP), so the mean prevalence of VAP was lower in the probiotic group than in the placebo group. The total rate of nosocomial infections among preterm infants was nonsignificantly higher in the probiotic group compared to the control group. Conclusion: This systematic review shows that the administration of probiotics has moderate preventive or mitigating effects on the occurrence of VAP in ICU patients, CDI, AAD, and nosocomial infections among children. Consequently, applying antibiotics along with the proper probiotic species can be advantageous.
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INTRODUCTION: Periodontal diseases and dental caries are the two most common dental diseases caused by the dental plaque. OBJECTIVE: The aim of the present study was to review the clinical efficacy of probiotics for oral health in randomized controlled trials. METHODS: An electronic search was conducted in December 2021 in Embase, Medline, The Cochrane Library, ProQuest, and Google Scholar using the following keywords: "mouthwash" and "probiotics". The titles and abstracts of 3,775 articles were screened and 24 publications that fulfilled the inclusion criteria were included. RESULTS: A total of 24 clinical trials were reviewed, including 1612 participants receiving either probiotics or mouth treatments. The results of this review indicated that individuals receiving probiotic products have a significant reduction (65% reduction; p < 0.05) in the count of Streptococcus mutants in their mouths. It was also found that probiotic products were more effective or equal in effect compared to chlorhexidine in reducing oral pathogens, gingival index, and plaque index scores. On the other hand, the consumption of xylitol mouthwash was shown to cause an improvement in salivary parameters. Considering their safety and effectiveness, the use of probiotic products, such as kefir and mouthwashes, has been recommended against cariogenic bacteria and periodontal diseases. CONCLUSION: Probiotics are considered a safe alternative to conventional therapies, such as chlorhexidine and fluoride. Co-administration of chlorhexidine, fluoride, and probiotics seems to be a perfect package.
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Caries Dental , Enfermedades Periodontales , Probióticos , Humanos , Clorhexidina/uso terapéutico , Salud Bucal , Fluoruros , Caries Dental/prevención & control , Caries Dental/tratamiento farmacológico , Antisépticos Bucales/uso terapéutico , Probióticos/uso terapéutico , Enfermedades Periodontales/tratamiento farmacológico , Resultado del TratamientoRESUMEN
INTRODUCTION: Brucellosis is considered as one of the main zoonotic infections and a major public health concern worldwide. The aim of the present study was to evaluate various strategies for controlling brucellosis with an especial emphasis on efficacy of vaccination. AREAS COVERED: International databanks (Web of Science, PubMed, Embase) were searched for potentially relevant studies published from 1 January 2011 to 25 March 2021 using the following keywords: 'Brucella,' 'Brucella abortus,' 'Brucella melitensis,' 'Brucella canis,' 'Brucella suis,' 'brucellosis,' 'Bang disease,' 'undulant fever,' 'Malta fever,' 'vaccination,' 'vaccine,' and 'immunization.' The literature search was restricted to original articles published in English. EXPERT OPINION: Various methods are employed to prevent and control brucellosis, such as removing sick animals by slaughtering, separating sick animals from the herd, and vaccination. Preventing, controlling, and eradicating brucellosis requires a lot of financial support, perseverance, and time. In order to conduct a detailed study, it is recommended that more studies be conducted in developing countries and different parts of the world.
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Brucella melitensis , Brucelosis , Animales , Brucella abortus , Brucelosis/prevención & control , Humanos , Vacunación , Zoonosis/epidemiología , Zoonosis/prevención & controlRESUMEN
Brucellosis is a bacterial zoonosis caused by Brucella spp. which can lead to heavy economic losses and severe human diseases. Thus, controlling brucellosis is very important. Due to humans easily gaining brucellosis from animals, animal brucellosis control programs can help the eradication of human brucellosis. There are two popular vaccines against animal brucellosis. Live attenuated Brucella abortus strain 19 (S19 vaccine) is the first effective and most extensively used vaccine for the prevention of brucellosis in cattle. Live attenuated Brucella melitensis strain Rev.1 (Rev.1 vaccine) is the most effective vaccine against caprine and ovine brucellosis. Although these two vaccines provide good immunity for animals against brucellosis, the expense of persistent serological responses is one of the main problems of both vaccines. The advantages and limitations of Brucella vaccines, especially new vaccine candidates, have been less studied. In addition, there is an urgent need for new strategies to control and eradicate this disease. Therefore, this narrative review aims to present an updated overview of the available different types of brucellosis vaccines.
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OBJECTIVE: Helicobacter pylori is one of the most common causes of gastric infections in humans. It is estimated that approximately 50% of people around the world are infected with this bacterium. This study aimed to determine the antibiotic resistance pattern, as well as the frequency of cagA and vacA genes in H. pylori isolates obtained from patients in the clinical centers in Tabriz city, Iran. RESULTS: The culture method detected 100 (45.25%) H. pylori isolates from 221 biopsy samples during 3 years. The results showed that 63% and 81% of the isolates were positive for cagA and vacA genes, respectively. The highest resistance of isolates was seen against metronidazole (79%) and amoxicillin (36%), respectively. Also, the isolates showed the least resistance to tetracycline (8%).
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Helicobacter pylori , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Farmacorresistencia Microbiana , Genotipo , Helicobacter pylori/genética , Humanos , Irán/epidemiologíaRESUMEN
Background: Sub-minimal inhibitory concentrations of antibiotics have been indicated to affect the biofilm formation in pathogens of nosocomial infections. This study aimed to investigate the effects of meropenem and tigecycline at their sub-minimum inhibitory concentrations (MICs) on the biofilm formation capacity of Acinetobacter baumannii (A. baumannii), as well as the expression levels of genes involved in biofilm formation, quorum sensing, pili assembly and efflux pumps. Materials and methods: In this study, four non-clonal strains (AB10, AB13, AB32 and AB55), which were different from the aspects of antibiotic susceptibility and biofilm formation from each other were selected for the evaluation of antimicrobial susceptibility, biofilm inducibility at sub-MICs of meropenem and tigecycline and the gene expression levels (the abaI, abaR, bap, pgaA, csuE, bfmS, bfmR, ompA, adeB, adeJ and adeG genes). Result: A significant increase in the MICs of all antibiotics was demonstrated in the biofilm cells in each four strains. The biofilm formation was significantly decreased in all the representative strains exposed to tigecycline. However, the biofilm inducibility at sub-MICs of meropenem was dependent on strain genotype. In concordance with these results, Pearson correlation analysis indicated a positive significant correlation between the biofilm formation capacity and the mRNA levels of genes encoding efflux pumps except adeJ, the genes involved in biofilm formation, pili assembly and quorum sensing following exposure to meropenem and tigecycline at their sub-MICs. Conclusion: These results revealed valuable data into the correlation between the gene transcription levels and biofilm formation, as well as quorum sensing and their regulation at sub-MICs of meropenem and tigecycline.
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Background: SPATE (serine protease autotransporters of enterobacteriaceae) genes are considered as a group of the main virulence factors of Shigella species This study aimed to investigate for the first time the distribution of SPATE genes among Shigella spp. isolated from children with diarrhea infection in Ahvaz, Iran. Methodology: In this study, a total of 74 Shigella isolates were collected between August 2016 and June 2017 from feces of children with diarrhea and identified by biochemical and molecular methods for Shigella species. The frequency distribution of the SPATE genes, including pic, pet, sat, sigA and sepA, was evaluated using PCR. The genetic relationship of all isolates was evaluated by enterobacterial repetitive intergenic consensus-PCR. Results: The most common species of Shigella was S. flexneri, followed by S. sonnei and S. boydii. In total, 95.94% of Shigella isolates had at least one of the SPATE genes. The presence of pic, pet, sat, sigA and sepA genes was confirmed among 35.13%, 27%, 47.29%, 58.1% and 39.18% of Shigella isolates, respectively. Of these SPATE genes, the sat and sigA genes were recognized as the most common autotransporters among S. flexneri and S. sonnei isolates, respectively. Also, either S. flexneri or S. sonnei isolates belonging to a same clone type had similar SPATE genes profile. Conclusion: Our results revealed that the high distribution of SPATE genes among Shigella isolates in our region. Hence, this study highlights a need for epidemiological programs to monitor the distribution of SPATE genes locally for prevention from further dissemination of the Shigella isolates harboring them.
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Background: Metallo-ß-Lactamases (MBL) are usually encoded on the gene cassettes harboring integrons and disseminated easily among Acinetobacter baumannii isolates. This study was aimed to investigate the association of the genes encoding MBL with the presence of class 1 and 2 integrons among multidrug-resistant (MDR) A.baumannii isolates. Methodology: A total of 85 non-duplicated A.baumannii isolates were collected and evaluated for the amplification of blaOXA-51. The presence of genes encoding MBLs, including blaIMP, blaVIM, blaSIM, blaSPM, blaGIM, blaDIM and blaNDM , as well as intI 1 and intI 2 was evaluated by PCR. Also, the production of MBLs was screened phenotypically by the combination of EDTA and meropenem. Results: In this study, 77 out of 85 isolates were MDR. Also, 34 isolates had only intI 1, 10 had only intI 2 and 15 had both intI 1 and intI 2. The phenotypic detection of MBLs was found in 30 isolates, among which blaVIM was as the most common the gene encoding MBL followed by blaIMP, blaSPM and blaSIM . The gene cassettes analysis revealed that class 1 integron is often responsible for transferring the genes harboring MBLs. Conclusion: The production of MBLs among A. baumannii strains is one of the main mechanisms of resistance to carbapenems. Therefore, the development of inexpensive screening methods for the phenotypic detection of MBLs in clinical laboratories settings is essential. Also, our data revealed that the class 1 integron is often responsible for the dissemination of the MBL genes among A. baumannii isolates.
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Background: Staphylococcus epidermidis has emerged as the pathogen from neonatal septicemia. Antibiotic resistance and the capability of biofilm formation make these infections much harder to treat. Hence, the aim of this study was to investigate the association between biofilm formation, structure and antibiotic resistance in S. epidermidis isolated from neonatal septicemia. Methods: Overall, 65 S. epidermidis isolates were recovered from blood cultures of neonatal septicemia. Antibiotic resistance pattern and the biofilm production were determined using phenotypic methods. The presence of ica operon, the bhp, the aap genes and SCCmec types were screened using PCR. Results: Most S.epidermidis isolates were resistant to erythromycin, while all isolates were sensitive to linezolid and vancomycin. Fifty-three percent of S.epidermidis isolates were resistant to methicillin. SCCmec types II was found commonly among methicillin-resistant S. epidermidis (MRSE) strains. The biofilm formation was observed in 65% of S.epidermidis isolates and the majority have polysaccharide matrix. icaA and icaD genes were found in 40% and 19% of isolates. Twenty-three isolates (62%) produced dissolvable polysaccharide intercellular adhesion (PIA)-dependent biofilms in SM after growth in TSB with NaCl and 14 (37%) isolates produced dissolvable protein-dependent biofilms in PK after growth in TSB with glucose. Three isolates (62%) produced dissolvable polysaccharide intercellular adhesion. Conclusion: Our data indicate the high rates of antibiotic resistance and the capability of biofilm formation among S. epidermidis isolates. Hence, the transmission of these strains can cause an increased risk of serious nosocomial infections.
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BACKGROUND: The ability of biofilm formation is an effective way for Acinetobacter baumannii survival from stressed conditions. This present study was aimed to evaluate the association between biofilm formation, structure, the expression levels of genes related to biofilm formation and biofilm-specific resistance of A. baumannii strains isolated from burn infections in Ahvaz, Iran. METHODS: In this study, we assessed the antibiotic susceptibilities, ERIC-PCR typing, capacity of biofilm formation and biofilm structure of 64 A. baumannii isolates collected from burn infections. The distribution and the expression levels of genes involved in the biofilm formation including bap, ompA, abaI, pgaA and csuE were assessed by PCR and real-time PCR, respectively. RESULTS: We classified A. baumannii isolates in 14 clonal types of ERIC-PCR. Most A. baumannii isolates were resistant to all antibiotics tested except to tigecycline and colistin and had the biofilm formation capability but with different capacities. There was a significant inverse relationship between resistance to antibiotic agents and biofilm formation. The biofilm matrix of 50 strains consisted of polysaccharides together with DNA or proteins. The genes involved in the biofilm formation were detected in both biofilm-forming and non-biofilm forming; however, the expression levels of these genes were higher in biofilm producers compared with non-producers. CONCLUSION: The biofilm cells exhibited dramatically decreased susceptibility to antibiotic agents; hence, they have great significance for public health. Therefore, the determination of antibiotic susceptibilities in biofilm and planktonic mode, molecular typing, and capacity of biofilm formation in clinical setting is essential.
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BACKGROUND: Chlamydia trachomatis (C. trachomatis) is the main cause of bacterial sexually transmitted infections. In women, this infection can lead to tubal infertility. OBJECTIVE: In this study we investigated C. trachomatis among infertile and fertile women with both polymerase chain reaction (PCR) and ELISA methods in Ahvaz, Iran. MATERIALS AND METHODS: This case-control study was conducted at the Infertility Clinic of University Jahad, Ahvaz, Iran from January to August 2017. A total of 225 vaginal swabs and blood samples (100 infertile and 125 fertile women) were collected. Detection of C. trachomatis DNA was performed from vaginal swabs by amplification of MOMP gene. Also, anti C. trachomatis immunoglobulin M (IgM) and immunoglobulin G antibodies in the serum samples were recognized by enzyme-linked immunosorbent assay (ELISA). RESULTS: Results showed that, 6 (6%) infertile and 2 (1.6%) fertile women were positive for IgM (p=0.21). Also, PCR was positive for C. trachomatis infection in 5 infertile (5%) and 2 fertile women (1.6%) (p=0.35). We did not find any seropositive immunoglobulin G in both groups. CONCLUSION: In this study, no significant difference was found between fertile and infertile groups for C. trachomatis infection. Also, the correlation between IgM and PCR results revealed a relatively strong agreement and seems both PCR and IgM assays are appropriate for the accurate diagnosis of C. trachomatis infections.