RESUMO
BACKGROUND: Probiotics promote a healthy balance of gut bacteria and have many beneficial effects on human digestive physiology. Although, few side effects of probiotics have been reported. This study aimed to assess the safety of five probiotic candidate Lactobacillus strains isolated from healthy individuals by examining mutagenicity, genotoxicity, and oral toxic effects. METHODS: Five selected candidate probiotic (SCPs) strains were evaluated for genotoxicity (Ames test with Salmonella typhimurium), in vitro mammalian chromosome aberration test and an in vivo mouse micronucleus assay on peripheral blood of mice. To evaluate the oral dose toxicity, BALB/c mice models were treated repeatedly (2000, 1000, and 500 mg/kg body weight /day) for 28-days. RESULTS: The Ames test performed for two S. typhimurium strains TA 98 and TA100 (both in the absence and in the presence of S-9 metabolic activation system) did not show an increase in reverse mutation because of exposure to the SCPs in any of the doses (5.0, 2.5, 1.25, 0.625, and 0.3125 mg/plate). There was no genotoxicity in the SCPs treatment in the vitro chromosome aberration assay with Chinese hamster ovary cells (CHO-K1). In addition, none of the tested strains increased the frequency of micronucleated reticulocytes in reticulocytes, the SCPs with the studied doses caused no substantial variation in the experimental groups compared to the negative control group (p > 0.05). SCPs were not acutely toxic when administered to male and female BALB/c mice by single gavage at (2000, 1000, and 500 mg/kg b.w/day) with no mortality or clinical signs, change in body weight or macroscopic abnormalities were observed in this dose range. CONCLUSION: As a result, SCPs did not induce mutagenic potential in vitro with bacterial reverse mutation, clastogenicity, and in vivo tests in the ranges of concentrations evaluated in our study.
Assuntos
Mutagênicos , Probióticos , Animais , Peso Corporal , Células CHO , Aberrações Cromossômicas , Cricetinae , Cricetulus , Feminino , Humanos , Lactobacillus , Masculino , Camundongos , Testes de Mutagenicidade , Mutagênicos/toxicidadeRESUMO
A variety of bacteriocins originate from lactic acid bacteria, which have recently been modified by scientists. Many strains of lactic acid bacteria related to food groups could produce bacteriocins or antibacterial proteins highly effective against foodborne pathogens such as Staphylococcus aureus, Pseudomonas fluorescens, P. aeruginosa, Salmonella typhi, Shigella flexneri, Listeria monocytogenes, Escherichia coli O157:H7, and Clostridium botulinum. A wide range of bacteria belonging primarily to the genera Bifidobacterium and Lactobacillus have been characterized with different health-promoting attributes. Extensive studies and in-depth understanding of these antimicrobials mechanisms of action could enable scientists to determine their production in specific probiotic lactic acid bacteria, as they are potentially crucial for the final preservation of functional foods or for medicinal applications. In this review study, the structure, classification, mode of operation, safety, and antibacterial properties of bacteriocins as well as their effect on foodborne pathogens and antibiotic-resistant bacteria were extensively studied.
Assuntos
Antibacterianos , Bactérias , Bacteriocinas , Animais , Bactérias/efeitos dos fármacos , Bactérias/patogenicidade , Doenças Transmitidas por Alimentos/microbiologia , Microbioma Gastrointestinal , Humanos , Lactobacillales/metabolismo , CamundongosRESUMO
AIMS AND BACKGROUND: Lactobacillus spp. are an important element in breast milk. This component has a beneficial effect on the composition of the intestinal microflora and the intestinal immune system. The aim of this study was to isolate and identify Lactobacillus strains in breast milk and evaluate some of their probiotic properties, such as presence of bacteriocin genes, adhesion to HT-29 cell line, competition with enteropathogens in cell culture, and effect on serum level of lipids and digestive enzymes, and mice model of inflammatory bowel disease (IBD). MATERIALS AND METHODS: A total of 323 lactic acid bacteria (LAB) were isolated from breast milk samples of healthy mothers with the age ranges from 21 to 45 years old. These isolates were subjected to phenotypic and molecular experiments. The frequency of bacteriocin genes was determined by polymerase chain reaction (PCR). Adhesion of Lactobacillus isolates to HT-29 cells was measured based on the number of attached bacterial cells in 20 fields of the light microscopy. Competition test was done by colony count and real-time PCR procedures. Five strongly adhesive Lactobacillus strains were selected and administered orally to the treatment groups. After 8 days, the serum level of digestive enzymes and improvement in induced IBD, and after 14 days, the serum level of lipids (triglycerides, total cholesterol, HDL, and LDL) in treated mice were surveyed compared to the control groups. RESULTS: Based on the phenotypic and molecular experiments, L. casei, L. plantarum, L. rhamnosus, and L. acidophilus strains were isolated and identified in the breast milk samples. The highest frequency of bacteriocin genes belonged to Plantaricin B (100%), followed by Plantaricin D (84.7%), Plantaricin G (84.7%), and Plantaricin EF (54.3%). Also, 71.8% of the isolates were strongly adhesive, 21.8% were non-adhesive, and 6.4% were adhesive. Lactobacillus strains had a significant effect on the displacement of enteropathogens. The in vitro cholesterol-removing ability of L. casei (L1), L. casei (L2), L. casei (L3), L. plantarum (L4), and L. rhamnosus (L5) was 3.5, 31.5, 21.3, 18.7, and 27.3%, respectively. The serum level of total cholesterol in the L. plantarum (L4) group as well as LDL in the L. casei (L3) (p = .0108) and L. rhamnosus (L5) (p = .0206) groups decreased significantly compared to the control group. The serum level of lipase increased in all the treatment groups compared to the control group, which was significant in the L. plantarum (L4) group (p = .0390). Disease activity index (DAI) scores were improved significantly in L. casei (L3) group compared to the IBD control group (p < .0001). CONCLUSION: It could be concluded that lactobacilli strains isolated from the breast milk samples had good probiotic properties, such as presence of bacteriocin genes, attaching to enterocyte-like HT-29 cells, competing with intestinal pathogens, lowering cholesterol, and improving IBD. Thus, after further studies, they could be considered as probiotic strains.
Assuntos
Bacteriocinas , Doenças Inflamatórias Intestinais , Lactobacillus , Leite Humano/microbiologia , Probióticos , Adulto , Animais , Bacteriocinas/genética , Feminino , Humanos , Doenças Inflamatórias Intestinais/terapia , Camundongos , Pessoa de Meia-Idade , Mães , Adulto JovemRESUMO
The frequency of Listeria monocytogenes isolates collected from a total of 1150 samples including food (n = 300), livestock (n = 50), and human clinical (n = 800) was evaluated during 2008-2016. Antimicrobial resistance patterns, virulence factors, and molecular characteristics of these isolates were analyzed using disk diffusion method, sequencing, serotyping, and pulsed-field gel electrophoresis (PFGE). The analysis of 44 L. monocytogenes isolates showed that 72.7% (32 of 44) of all the isolates belonged to Serotype 1/2c, and 15.9% (7 of 44) belonged to Serotype 3c. All 44 isolates were resistant to one or more antimicrobial agents with the most frequent resistance to penicillin (75%) and tetracycline (47.7%). Of the 44 L. monocytogenes strains, 100, 69.2, and 62.5% of livestock, human, and food strains were resistant to penicillin, respectively. Using pulsed-field gel electrophoresis (PFGE) technique, the isolates' genetic diversity was determined, and 28 PFGE patterns with 8 common (CT) and 20 single types (ST) were identified. This study highlights the high prevalence of Serotype 1/2c in clinical and livestock samples, while different serotypes were observed in food samples. The presence of rare serotypes such as 4c, belonging to the Lineage III, as well as 4e and 1/2c which are infrequent in Iran indicates that paying attention to uncommon serotypes, especially 1/2c, during the listeriosis outbreaks is necessary.
Assuntos
Microbiologia de Alimentos , Listeria monocytogenes , Listeriose , Virulência , Animais , Técnicas de Tipagem Bacteriana , Farmacorresistência Bacteriana/genética , Eletroforese em Gel de Campo Pulsado , Humanos , Irã (Geográfico)/epidemiologia , Listeria monocytogenes/classificação , Listeria monocytogenes/genética , Listeria monocytogenes/patogenicidade , Listeriose/epidemiologia , Listeriose/veterinária , Gado/microbiologia , Tipagem Molecular , SorotipagemRESUMO
BACKGROUND: Probiotics have been associated with many beneficial effects in human digestive physiology. The aim of this study was to evaluate the effect of improved formulation of chitosan-alginate microcapsules of Bifidobacterium strains on serum triglycerides, cholesterol, HDL, and LDL in mice. METHODS: Five approved probiotic strains of Bifidobacterium were tested for anti-proliferative effect and interleukin-8 induction on HT-29 cell lines. Bifidobacterium strains plus five approved Lactobacillus were encapsulated in chitosan-alginate microcapsules and tested for its survival in simulated gastrointestinal conditions. These microcapsules were administered to 4 groups of mice (including 1. Bif (Bifidobacterium strains), 2. Lac (Lactobacillus strains), 3. Bif-Lac (Bifidobacterium plus Lactobacillus strains) and 4. Control) for 8 days. At eighth day, the blood of mice were taken and serum levels of triglycerides, cholesterol, HDL, and LDL of them were determined. RESULTS: All of the Bifidobacterium strains significantly (P < 0.001) reduced secretion of IL-8 in HT-29 cells as well as maximum antiproliferative effects (P < 0.001). In addition, all microcapsules showed impressive survival rate in bile (>%94.1) and gastrointestinal (>%78.28) conditions (P < 0.05). Only Bif-Lac group displayed significantly lower serum cholesterol and LDL levels than control group (P < 0.05). Besides, all groups indicate statistically significant weight loss of mice during the 8 days in comparison with the control group (P < 0.05). CONCLUSION: The results of this study showed that the microencapsulated probiotics with alginate and chitosan had an effective mean of delivery of viable bacterial cells and non-pharmacological interventions use to reduce serum cholesterol and LDL levels in in-vivo condition.
Assuntos
Quitosana , Probióticos , Alginatos , Animais , Bifidobacterium , Cápsulas , Colesterol , CamundongosRESUMO
Probiotics could be considered as attractive candidates for preventing tumor growth through maintaining homeostasis. The aim of this study was to evaluate the inhibitory effect of a cocktail of five Lactobacillus species on human colorectal carcinoma cell line HT-29. The anti-proliferative and apoptotic effects of Lactobacilli cocktail were evaluated using MTT and flow cytometry tests, respectively. Quantitative real-time polymerase chain reaction (qPCR) was used to analyze the expression of several genes in the Notch (notch, hes1, msi1, and numb) and Wnt/ß-catenin (CTNNB1 and CCND1) pathways, following the treatment of HT-29â¯cells with Lactobacilli cocktail. The treatment by Lactobacilli cocktail induced a significant anti-proliferative effect and late stage apoptosis among the cancer cells (pâ¯<â¯0.05). Compared to the untreated cells, Lactobacilli cocktail induced the down-regulation of notch, hes1, and msi1 genes and up-regulation of numb gene in the Notch pathway as well as the down-regulation of CTNNB1 and CCND1 genes in the Wnt/ß-catenin pathway in a time-dependent manner (pâ¯<â¯0.05). CONCLUSION: Lactobacilli cocktail was shown to have beneficial anti-tumor effects on HT-29â¯cells by modulating the Notch and Wnt/ß-catenin pathways; therefore, the use of Lactobacilli probiotics as nutritional supplements may prevent the incidence of colon cancer.
Assuntos
Lactobacillus/metabolismo , Transdução de Sinais , Via de Sinalização Wnt , Apoptose , Proliferação de Células , Ciclina D1/genética , Ciclina D1/metabolismo , Regulação Bacteriana da Expressão Gênica , Células HT29 , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição HES-1/genética , Fatores de Transcrição HES-1/metabolismo , beta Catenina/genética , beta Catenina/metabolismoRESUMO
Probiotic bacteria are known to exert a wide range of anticancer activities on their animal hosts. In the present study, the anticancer effect of a cocktail of several potential probiotic Lactobacillus species (potential probiotic L.C) was investigated in vitro and in vivo. MTT and Flow cytometry tests results showed that administration of live potential probiotic L.C significantly decreased the HT-29 and CT-26 cells proliferation and induced late apoptotis in a time-dependent manner. In addition, quantitative real-time polymerase chain reaction (qPCR) results showed that exposure of potential probiotic L.C to both HT-29 and CT-26 cells during the incubation times resulted in the upregulation (apc and CSNK1ε for HT-29, CSNK1ε and gsk3ß for CT-26) and downregulation (CTNNB1, CCND1, pygo2, axin2 and id2) of the Wnt/ß- catenin pathway-related genes in a time-dependent manner. The significance of in vitro anticancer effect of potential probiotic L.C was further confirmed in an experimental tumor model. Data from the murine model of colorectal cancer (CRC) induced by Azoxymethane (AOM) and Dextran Sulfate Sodium (DSS) showed significantly alleviated inflammation and tumor development in AOM/DSS/L.C-injected mice compared to the AOM/DSS-injected mice. Tumor growth inhibition was accompanied by potential probiotic L.C-driven upregulation and downregulation of the Wnt/ß-catenin pathway-related genes, similar to the in vitro results. These results showed that potential probiotic L.C inhibited the tumor growth, and that its anticancer activity was at least partially mediated through suppressing the Wnt/ß-catenin pathway. Overall, the present study suggested that this probiotic could be used clinically as a supplement for CRC prevention and treatment.
Assuntos
Neoplasias Colorretais/terapia , Lactobacillus , Probióticos/uso terapêutico , Via de Sinalização Wnt , Animais , Apoptose , Azoximetano , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/microbiologia , Progressão da Doença , Feminino , Citometria de Fluxo , Microbioma Gastrointestinal , Células HT29 , Humanos , Inflamação , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase em Tempo Real , beta Catenina/metabolismoRESUMO
Inflammatory bowel disease (IBD) comprises two major illnesses: Crohn's disease (CD) and ulcerative colitis (UC). Dextran sulfate sodium (DSS) mouse colitis model has been used in understanding the mechanism of IBD. This study was conducted to examine selected Lactobacillus spp. as potential IBD treatment in the DSS-induced animal model. Balb/c mice were used and colitis was induced by adding 5% dextran sodium sulfate into the drinking water for 8 days. Colon length, disease activity index (DAI) and histological analysis were measured as markers of inflammation in DSS colitis mice. The majority of the Lactobacillus species significantly prevented the shortening of the colon length compared with the DSS group. The DAI scores of mice were significantly reduced following usage of four Lactobacillus strains included: Lactobacillus plantarum 03 and 06, Lactobacillus brevis 02 and Lactobacillus rhamnosus 01. The histological analysis exhibited that oral administration of Lactobacillus strains had therapeutic effects on mice colitis. L. plantarum and L. brevis showed better therapeutic effect against DSS-induced acute colitis mice. The probiotic activities of these three isolates indicated that the probiotic effects were strain specific and none of these useful bacteria could exhibit all of the valued probiotic properties simultaneously.
Assuntos
Colite/tratamento farmacológico , Lacticaseibacillus rhamnosus/metabolismo , Lactobacillus plantarum/metabolismo , Levilactobacillus brevis/metabolismo , Probióticos/uso terapêutico , Animais , Colite/induzido quimicamente , Colite/microbiologia , Colo/microbiologia , Colo/patologia , Sulfato de Dextrana , Modelos Animais de Doenças , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Levilactobacillus brevis/crescimento & desenvolvimento , Lactobacillus plantarum/crescimento & desenvolvimento , Lacticaseibacillus rhamnosus/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos BALB CRESUMO
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RESUMO
BACKGROUND: Infections caused by bacteria are a foremost cause of morbidity and mortality in the world. The common strategy of treating bacterial infections is by local or systemic administration of antimicrobial agents. Currently, the increasing antibiotic resistance is a serious and global problem. Since the most important agent for infection is bacteria attaching to host cells, hence, new techniques and attractive approaches that interfere with the ability of the bacteria to adhere to tissues of the host or detach them from the tissues at the early stages of infection are good therapeutic strategies. METHODS: All available national and international databanks were searched using the search keywords. Here, we review various approaches to anti-adhesion therapy, including use of receptor and adhesion analogs, dietary constituents, sublethal concentrations of antibiotics, and adhesion-based vaccines. RESULTS: Altogether, the findings suggest that interference with bacterial adhesion serves as a new means to fight infectious diseases. CONCLUSION: Anti-adhesion-based therapies can be effective in prevention and treatment of bacterial infections, but further work is needed to elucidate underlying mechanisms.
Assuntos
Aderência Bacteriana/fisiologia , Infecções Bacterianas/prevenção & controle , Anti-Infecciosos/uso terapêutico , Vacinas Bacterianas/uso terapêutico , Relação Dose-Resposta a Droga , HumanosRESUMO
BACKGROUND: Clostridioides difficile is a major cause of nosocomial infectious diarrhea in hospitalized patients throughout the world. METHODS: A multiplex real-time PCR assay was developed and evaluated in comparison with toxigenic culture (TC) (as gold standard method) for direct detection of toxigenic C. difficile in fecal specimens. The multiplex real-time PCR assay simultaneously detected glutamate dehydrogenase (gluD), toxin A (tcdA), toxin B (tcdB), and binary toxin (cdtB) genes in stool samples. RESULTS: The results of multiplex real-time PCR were compared to those of the TC method in 250 patients suspected of C. difficile infection. The prevalence of positive TC was 13.6%. Forty-two stool samples (16.8%) were determined to be gluD+ using multiplex real-time PCR. These included 35 (83.3%) toxigenic (32 tcdA+, tcdB+ and three tcdB+) and 7 (20.0%) were cdtB+. The multiplex real-time PCR assay had a sensitivity of 91.45%, specificity of 99.54%, and positive and negative predictive values of 97% and 98.6%, respectively, compared to the TC method for diagnosis of C. difficile. The analytical sensitivity of the multiplex real-time PCR assay was estimated to be 102 CFU/g of stools and 0.0200 pg of genomic DNA from culture. The analytical specificity was determined to be 100% by using enteric and non-C. difficile standard bacterial strains. CONCLUSIONS: The molecular method developed in the study was rapid, sensitive, and specific for detection of toxigenic C. difficile. It is applicable to be performed in clinical laboratories and correlated well with the results obtained by TC.
Assuntos
Clostridioides difficile/isolamento & purificação , Diarreia/microbiologia , Fezes/química , Reação em Cadeia da Polimerase em Tempo Real/métodos , Idoso , Idoso de 80 Anos ou mais , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Técnicas de Laboratório Clínico , Diarreia/diagnóstico , Enterocolite Pseudomembranosa/diagnóstico , Enterotoxinas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex , Curva ROC , Sensibilidade e EspecificidadeRESUMO
In healthcare settings, contamination of environment with toxigenic and hypervirulent Clostridioides difficile strains is a serious concern. Here, we assessed whether patients with C. difficile have a role to play in the dissemination of C. difficile in our settings or other sources are implicated in its circulation. A total of 700 fecal specimens and 1435 environmental samples from surfaces, equipment and air of rooms occupied by patients suspected of C. difficile infection were taken from 4 tertiary hospitals in Tehran, Iran between April 2016 and August 2017. Antibiotic susceptibility testing and detection of resistance genes were performed for the environmental isolates. The clinical and environmental isolates of C. difficile were subjected to Pulsed Field Gel Electrophoresis (PFGE) analysis. Forty three (6.14%) and 2 (0.13%) isolates of C. difficile were recovered from the clinical and environmental samples, respectively. In the clinical settings, 2 patients were suspected of recurrent C. difficile infection. Thirty distinct pulsotypes were found among the C. difficile isolates including 28 singletons and 2 common types. One of the two environmental isolates was isolated from floor in the Medical ward, of pulsotype/ribotype/toxinotype PT10/New ribotype/toxinotype V, harbored cdtA/B and tcdC-A, and resistant to ciprofloxacin. The other one was isolated from air of a room in ICU, assigned to PT11/RT001/toxinotype 0, belonged to tcdC-sc3 genotypes and resistant to metronidazole. The environmental isolates did not generate amplicons in PCR assays targeting vanA and nim genes. This study provided evidence for dissemination of genetically diverse strains of C. difficile in hospitalized patients, presence of C. difficile in hospital air, existence of binary toxin positive/antibiotic-resistant isolate on the floor and intra-hospital dissemination of this pathogen.
Assuntos
Clostridioides difficile/classificação , Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/microbiologia , Eletroforese em Gel de Campo Pulsado , Microbiologia Ambiental , Variação Genética , Tipagem Molecular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Clostridioides difficile/efeitos dos fármacos , Clostridioides difficile/genética , Farmacorresistência Bacteriana , Fezes/microbiologia , Feminino , Genótipo , Humanos , Irã (Geográfico) , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Centros de Atenção Terciária , Adulto JovemRESUMO
The purpose of the present study was to isolate Lactobacillus bacteria from mother's milk and to assess their probiotic potential. Sixty breast milk samples were collected from the volunteered mothers aged from 19 to 35 and from rural areas of Lorestan and Markazi Provinces, Iran. At first, 970 bacill-shaped bacterial colonies were isolated from these samples and stored in proper condition. Two hundred isolates were randomly selected and investigated for their ability to tolerate acidic condition and to tolerate bile salt as well. Only 33 isolates could withstand the exposure to low pH and bile salt. The isolates were identified using PCR primer specific to Lactobacillus and it was demonstrated that eighteen of thirty-three isolates were belonged to the Lactobacillus. Among the isolates, 16 and 2 of them were Lactobacillus reuteri and L. gasseri, respectively. In addition, the antibiotic resistance of the isolates was determined using disc diffusion method and all of the isolates were shown to be sensitive to eight out of the twelve investigated antibiotics. Moreover, the antagonistic effect of the isolates was inspected on ten indicator pathogens. Interestingly, all of the pathogenic bacteria were inhibited by Lactobacillus isolates. In addition, to partially understand the nature of inhibition mechanism, well diffusion deployed for two randomly-selected indicator bacteria and the resulting halos of three isolates were statistically significant compared to other lactobacillus (pâ¯<â¯0.05). Subsequently, bacteriocin genes (plnS, Laf, gasA) were identified by PCR among the isolates. The results showed that only 2 isolates possessed the gasA gene which were in accordance with well diffusion test. Consequently, eighteen Lactobacillus isolated from breast milk samples which all of them were able to tolerate low pH and bile salt. Similarly, all of the Lactobacillus isolates were proved to inhibit the growth of pathogen strains and two of them possess a bacteriocin-related gene.
Assuntos
Bacteriocinas/biossíntese , Bacteriocinas/genética , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Lactobacillus/metabolismo , Leite Humano/microbiologia , Adulto , Antibacterianos/farmacologia , Antibiose , Bactérias/patogenicidade , Proteínas de Bactérias/genética , Ácidos e Sais Biliares , DNA Bacteriano , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana , Feminino , Genes Bacterianos/genética , Humanos , Concentração de Íons de Hidrogênio , Irã (Geográfico) , Lactobacillus/efeitos dos fármacos , Tipagem Molecular , Mães , Probióticos , Adulto JovemRESUMO
OBJECTIVES: To elucidate the association between asymptomatic infections caused by Mycoplasma genitalium and male infertility, and evaluate the role of antibiotic therapy in treatment of this failure. METHODS: A total of 165 infertile males having abnormal semen parameters (study group) and 165 healthy fertile men (control group) were included. Semen samples were taken from all participants and after analyzing for semen parameters, undergone real-time PCR, microbial culture, and reactive oxygen species (ROS), as well as total antioxidant capacity (TAC) assays. Infected individuals of study group were treated with antibiotic. One month after the treatment completion, second semen samples were taken and subjected to all the tests mentioned. The data were analyzed using SPSS statistical software, version 22.0. RESULTS: The frequency of M. genitalium was significantly higher in the infertile men compared with the fertile ones (9.7% vs. 1.2%; p = 0.001). Mean cycle threshold (C t) value was lower in infected infertile than infected fertile men (p < 0.001). All semen parameters, except volume, pH, and viscosity, were improved (p < 0.05), most of which reached their normal range; leukocytes in seminal fluid decreased (p = 0.02), the level of TAC was elevated (p = 0.002), and ROS level as well as ROS/TAC ratio reduced after antibiotic treatment (p = 0.03). Wives of seven infected infertile men (43.8%) became pregnant 4 months after the treatment completion. CONCLUSIONS: Asymptomatic infection caused by M. genitalium is correlated with male infertility and antibiotic therapy can improve the semen quality and be used to treat male infertility.
Assuntos
Antibacterianos/administração & dosagem , Infertilidade Masculina/epidemiologia , Infecções por Mycoplasma/epidemiologia , Mycoplasma genitalium/isolamento & purificação , Sêmen/fisiologia , Adulto , Antioxidantes/metabolismo , Humanos , Infertilidade Masculina/tratamento farmacológico , Infertilidade Masculina/microbiologia , Infertilidade Masculina/fisiopatologia , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Infecções por Mycoplasma/tratamento farmacológico , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/fisiopatologia , Espécies Reativas de Oxigênio/metabolismo , Análise do Sêmen , Adulto JovemRESUMO
It is known that type 2 diabetes (T2D) in humans could be linked to the composition of gut microbiota. The aim of this study was to evaluate three faecal bacterial species, including Bacteroides fragilis, Bifidobacterium longum and Faecalibacterium prausnitzii in patients with T2D. This case control study included 18 patients with T2D and 18 matched persons without diabetes. The concentrations of B. fragilis, B. longum and F. prausnitzii were determined by quantitative Real-Time PCR. Quantitative PCR analysis revealed that the gut bacterial composition in patients with T2D was partially different from that in the healthy individuals. Faecalibacterium prausnitzii was significantly lower in patients with T2D (P-value = 0.038). Bacteroides fragilis was under-represented in the microbiota of the group with diabetes, but its difference between two groups was not significant (P-value = 0.38). No difference was observed for B. longum community between the both groups (P-value = 0.99). Characterization of specific species of intestinal microbiota shows some compositional changes in patients with T2D. The results may be valuable for developing strategies to control type 2 diabetes by modifying the intestinal microbiota. Long-term studies with emphasis on other bacterial groups are suggested to clarify the association of T2D with gut microbiota.
Assuntos
Bacteroides fragilis/isolamento & purificação , Bifidobacterium longum/isolamento & purificação , Diabetes Mellitus Tipo 2/microbiologia , Faecalibacterium prausnitzii/isolamento & purificação , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Carga Bacteriana , Estudos de Casos e Controles , Fezes/microbiologia , Humanos , Irã (Geográfico) , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Antibacterial activity of Bifidobacterium species has been considered as an important probiotic property for development of human gut immunity. This study was conducted to assess the genotypes and antibacterial activities of the native Bifidobacterium isolates obtained from the human's breast milk and the feces of their paired infants. Fifty-six samples from twenty-eight mothers' milk and paired infants feces were collected and cultured. Suspicious colonies were picked up and confirmed by phenotypic and molecular identifications. Randomly amplified polymorphic DNA (RAPD-PCR) and antibacterial activity were carried out. Amongst 56 samples, 41 different Bifidobacterium species including 12 B. breve, 14 B. longum, and 15 B. bifidum were isolated. Out of which, 12 isolates including B. longum (6), B. breve (4) and B. bifidum (2) were shared between six mother-infant pairs. Only three strains of B. longum showed 100% similarity in their RAPD-PCR. No significant difference was observed in the antibacterial activity of the Bifidobacterium isolates, with the same or different RAPD-PCR profile, against the enteric bacteria. Overall, 29% of the Bifidobacteria species isolated from the mothers milk and their paired infants feces were shared. All species of Bifidobacteria showed the universal role of antipathogens activities irrespective of the host and the isolation site.
Assuntos
Antibacterianos/farmacologia , Bifidobacterium/classificação , Bifidobacterium/genética , Bifidobacterium/isolamento & purificação , Fezes/microbiologia , Genótipo , Leite Humano/microbiologia , Bactérias/efeitos dos fármacos , Aleitamento Materno , DNA Bacteriano/genética , Feminino , Humanos , Lactente , Recém-Nascido , Irã (Geográfico) , Mães , Fenótipo , Probióticos , Técnica de Amplificação ao Acaso de DNA Polimórfico , Fatores de TempoRESUMO
Enterococci have a widespread attendance in the circumference and belongs to the enteric commensal microbiota. Most of them produce the antimicrobial compounds and have an inhibition effect on pathogenic microorganisms. The objective of this study was to characterize the enterococcal strains isolated from human normal flora and assess their antibacterial activity. Enterococcal isolates were obtained from the feces of eighteen healthy humans. All enterococcal species were identified by biochemical and species-specific polymerase chain reaction (PCR). These isolates were investigated further to examine their ability to inhibit growth of Salmonella typhi, Shigella flexneri and Escherichia coli by well diffusion assay. Furthermore, antibiotic susceptibility test was performed and genetic relatedness of all isolates was evaluated by Pulse Field Gel Electrophoresis (PFGE). In all, 432 isolates were obtained from fecal samples. All of the isolates identified as Enterococcus faecium by biochemical and molecular (PCR) methods. Using repetitive element palindromic (REP)-PCR method 54 patterns have been obtained and were selected for further evaluation. The results indicated that 66%, 38% and 24% of our isolates had antimicrobial effect against S. typhi, S flexneri and enteroaggregative Escherichia coli (EAEC), respectively. On the other hand, there was no significant inhibition effect against enteropathogenic E. coli (EPEC) and enterotoxigenic E. coli (ETEC). All isolates were sensitive to vancomycin, teicoplanin, linezolid, ampicillin, chloramphenicol and gentamicin. On the other hand, the resistance rates for erythromycin, tetracycline and ciprofloxacin were 20%, 22%, and 1.8% respectively. In addition, the analysis of PFGE showed forty patterns with eight (40.7%) common types (CT) and thirty two (59.2%) single types (ST). Among eight common types, only one common type (CT5) had similar antimicrobial effect. These results suggested that enterococcal isolates obtained from human normal flora have potential antibacterial effect against S. typhi, S. flexneri and E. coli.
Assuntos
Antibiose , Enterococcus faecium/isolamento & purificação , Enterococcus faecium/fisiologia , Escherichia coli/crescimento & desenvolvimento , Microbioma Gastrointestinal , Salmonella typhi/crescimento & desenvolvimento , Shigella flexneri/crescimento & desenvolvimento , Técnicas de Tipagem Bacteriana , Eletroforese em Gel de Campo Pulsado , Enterococcus faecium/classificação , Enterococcus faecium/genética , Fezes/microbiologia , Humanos , Tipagem Molecular , Reação em Cadeia da PolimeraseRESUMO
To assess the molecular characterization of disseminated vancomycin-resistant enterococci (VRE) in the intensive care units, 546 enterococci isolates were collected from different clinical samples in a prospective observational study. The results showed that a total number of 33 isolates (6 %) were resistant to vancomycin. Most of the VRE isolates 11 (34 %) were isolated from intensive care units (ICUs). 18 (55 %) VRE isolates were obtained from urinary tract infections. The results from pulsed-field gel electrophoresis showed five common types (CT) and 13 single types (ST) among the VRE isolates. The analysis showed two and one major CTs and ST among the ICUs isolates, respectively. Tn1546 transposon was analyzed using ClaI-digested long PCR (L-PCR) RFLP followed by sequencing. The results showed the presence of two different lineages of transposon among the two clonal groups. Lineage 1 with the arrangement of Tn1546 prototype in the first clonal group and the second lineage with 13 kb harboring two insertion sequences, IS1216 V and IS1542. DNA hybridization showed that vanA gene in all VRE isolates, with an exception of one isolate, was present in the same location on the genome. Overall, the results suggest that a few VRE clonal types were disseminated in ICUs in hospitals in Iran which were able to transfer their vanA with high conjugation frequency.
Assuntos
Enterococcus faecium/classificação , Enterococcus faecium/genética , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Resistência a Vancomicina , Análise por Conglomerados , Elementos de DNA Transponíveis , Eletroforese em Gel de Campo Pulsado , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/isolamento & purificação , Genótipo , Humanos , Unidades de Terapia Intensiva , Irã (Geográfico)/epidemiologia , Epidemiologia Molecular , Tipagem Molecular , Análise de Sequência de DNA , Infecções Urinárias/epidemiologia , Infecções Urinárias/microbiologiaRESUMO
Background: The use of probiotics is emerging as an innovative approach to managing oral health issues and mediating the immune system. The current study assessed the in vitro impacts of non-orally isolated probiotics on periodontitis and tooth decay pathogens. Methods: Briefly, the persistence of probiotics in exposure to oral cavity enzymes, hydrogen peroxide, and saliva samples was examined. It was also investigated the biofilm formation and aggregation ability of probiotics, the adherence of probiotics in human gingival fibroblast cell (HGFC) lines and molar teeth samples, and the potential of probiotics to co-aggregate with oral pathogens. Additionally, the current study evaluated the effects of live probiotics on virulence gene expression, biofilm production of main oral pathogens, and changes in inflammation markers. Results: The probiotics remained alive when exposed to enzymes in the oral cavity, hydrogen peroxide, and saliva at baseline, 1, 3, and 5 h after incubation at 37°C (p-value <0.05). Probiotics demonstrated to produce biofilm and aggregation, as well as adherence to HGFCs and maxillary molars (p-value >0.05). They showed significant co-aggregation with oral pathogens, which were recorded as 65.57% for B. bifidum 1001 with S. mutans, 50.06% for B. bifidum 1005 with P. gingivalis, 35.6% for L. plantarum 156 with F. nucleatum, and 18.7% for B. longum 1044 with A. actinomycetemcomitans after 8 h of incubation. A balance between pro-inflammatory and anti-inflammatory cytokines, along with inhibition of biofilm formation and changes in virulence gene transcripts, were observed. However, most of these changes were not statistically significant (p-value >0.05). Conclusion: This study demonstrated the direct link between adhesiveness, aggregation, and biofilm formation with probiotic antibacterial activity. In addition to the careful selection of suitable probiotic strains, the concentration and origin of probiotic isolates should be considered.
RESUMO
Acinetobacter baumannii strains belonging to global clone 2 (GC2) contain resistance islands (AbGRIs), which are composed of genes conferring resistance to older and newer antibiotics. Here, to locate these genes in AbGRIs, the GC2 strains from Tehran, Iran were examined. Among the 170 A. baumannii, 90 isolates were identified as GC2. Of the genes that confer resistance to older antibiotics, tetA(B), tetR(B) (tetracyclines), strA, and strB (aminoglycosides) were located in AbGRI1 of 65 GC2 isolates (72.2%). Of the other aminoglycosides, the aphA1b was located in AbGRI2-12b (63.6%), AbGRI2-12a (21.2%), or AbGRI2-1 (15.1%). The aacC1 and aadA1 genes were co-located within AbGRI2-1 (5.5%). The armA was located in AbGRI3-4 (77.7%) and AbGRI3ABI221 (22.2%). Of sulfonamides, the sul1 was located within AbGRI2-1 (5.5%). Of beta-lactams, the blaTEM was located in AbGRI2-12b (42%), AbGRI2-12a (14%), AbGRI2-1 (10%), or AbGRI2ABI257 (34%). The oxa23 gene conferring resistance to newer antibiotics (carbapenems) was located in AbaR4 (81.1%); of them, the AbaR4 was located within AbGRI1 in 45.2% of the isolates. This study showed that the GC2 isolates, which contained at least one AbGRI, disseminate in the hospital. Hence, it is likely that the AbGRIs play a significant role in conferring resistance to older and newer antibiotics in GC2 isolates from Iran. IMPORTANCE The majority of Acinetobacter baumannii isolates that are resistant to multiple antibiotics belong to one of the two major global clones, namely global clone 1 (GC1) and global clone 2 (GC2). The resistance islands, which contain variable assortments of transposons, integrons, and specific resistance genes, have been characterized in the genome of these GCs. In GC2 A. baumannii, the chromosomally located A. baumannii genomic resistance islands (AbGRIs) carry the genes conferring resistance to older and newer antibiotics. In this context, we tested whether GC2 isolates collected from a referral hospital carry the AbGRIs containing these genes. This study provided evidence for the circulation of the GC2 A. baumannii strains harboring AbGRI resistance islands between different wards of a referral hospital.