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1.
Microb Cell Fact ; 22(1): 256, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087304

RESUMO

BACKGROUND: Gamma-aminobutyric acid (GABA) is a non-protein amino acid with neuroinhibitory, antidiabetic, and antihypertensive properties and is used as a drug for treating anxiety and depression. Some strains of lactobacilli are known to produce GABA and strengthen the gut barrier function which play an important role in ameliorating the effects caused by the pathogen on the gut barrier. The probiotic bacteria are also known to modulate the human fecal microbiota, however, the role of GABA-producing strains on the gut epithelium permeability and gut microbiota is not known. RESULTS: In this study, we report the production of high levels of GABA by potential probiotic bacterium Limosilactobacillus fermentum L18 for the first time. The kinetics of the production of GABA by L18 showed that the maximum production of GABA in the culture supernatant (CS) occurred at 24 h, whereas in fermented milk it took 48 h of fermentation. The effect of L18 on the restoration of lipopolysaccharide (LPS)-disrupted intestinal cell membrane permeability in Caco-2 monolayers showed that it significantly restored the transepithelial electrical resistance (TEER) values, by significantly increasing the levels of junction proteins, occludin and E-cadherin in L18 and LPS-treated Caco-2 cells as compared to only LPS-treated cells. The effect of GABA-secreting L18 on the metataxonome of human stool samples from healthy individuals was investigated by a batch fermentor that mimics the conditions of the human colon. Although, no differences were observed in the α and ß diversities of the L18-treated and untreated samples at 24 h, the relative abundances of bacterial families Lactobacillaceae and Bifidobacteriaceae increased in the L18-treated group, but both decreased in the untreated groups. On the other hand, the relative abundance of Enterobacteriaceae decreased in the L18 samples but it increased in the untreated samples. CONCLUSION: These results indicate that Li. fermentum L18 is a promising GABA-secreting strain that strengthens the gut epithelial barrier by increasing junction protein concentrations and positively modulating the gut microbiota. It has the potential to be used as a psychobiotic or for the production of functional foods for the management of anxiety-related illnesses.


Assuntos
Microbioma Gastrointestinal , Limosilactobacillus fermentum , Probióticos , Humanos , Células CACO-2 , Lipopolissacarídeos , Função da Barreira Intestinal , Bactérias/metabolismo , Probióticos/uso terapêutico
2.
Indian J Public Health ; 67(4): 530-532, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38934812

RESUMO

SUMMARY: LAMP assay is widely used for detecting pathogens. We observed that the conventional and gradient polymerase chain reaction (PCR) could not detect the extracted Escherichia coli DNA; real-time PCR was able to detect up to a certain limit (10-8 bacterial dilution). At the same time, the LAMP assay could detect the bacteria at a much lower concentration (10-14 dilution). The results of the LAMP assay were evaluated using agarose gel electrophoresis and DNA binding dye (PicoGreen), but only gel electrophoresis gave reliable results. Therefore, we propose using electrophoresis-based amplicon detection to overcome the limitations of dye-based detection. We believe that this amplicon detection will go a long way in the screening of potable drinking water.


Assuntos
Escherichia coli , Técnicas de Amplificação de Ácido Nucleico , Microbiologia da Água , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Humanos , Eletroforese em Gel de Ágar/métodos , DNA Bacteriano/análise , Técnicas de Diagnóstico Molecular/métodos , Água Potável/microbiologia
3.
Indian J Public Health ; 66(4): 487-489, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37039178

RESUMO

Hygiene hypothesis and sanitization are two important pivots of modern civilization. The drinking water should be free from urine and stool contamination. Coliform test is popular for understanding feces contamination. However, understanding urine contamination in drinking water is a difficult task. On the other hand, urine contamination can cause disease like leptospirosis. It occurs mainly in animals and infects humans through contaminated water, food, and soil and causes serious consequences. Rat urine is the most common source of such disease outbreaks. Further, sophisticated laboratories with high-end technologies may not be present at the site of disease outbreaks. In this context, we have proposed a spectrofluorimetric approach to screen urine contamination in water. The screening method can sense up to 156 nl/ml of rat urine.


Assuntos
Água Potável , Leptospirose , Vigilância em Saúde Pública , Poluição da Água , Animais , Humanos , Ratos , Água Potável/análise , Índia/epidemiologia , Leptospirose/epidemiologia , Espectrometria de Fluorescência , Urina , Poluição da Água/efeitos adversos , Poluição da Água/análise , Vigilância em Saúde Pública/métodos
4.
BMC Microbiol ; 21(1): 39, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33541292

RESUMO

BACKGROUND: Increase in the number of infections caused by Gram-negative bacteria in neutropenic cancer patients has prompted the search for novel therapeutic agents having dual anticancer and antimicrobial properties. Bacteriocins are cationic proteins of prokaryotic origin that have emerged as one of the most promising alternative antimicrobial agents with applications as food preservatives and therapeutic agents. Apart from their antimicrobial activities, bacteriocins are also being explored for their anticancer potential. RESULTS: In this study, a broad-spectrum, cell membrane-permeabilizing enterocin with a molecular weight of 65 kDa was purified and characterized from the culture supernatant of vaginal Enterococcus faecium 12a. Enterocin 12a inhibited multidrug-resistant strains of various Gram-negative pathogens such as Salmonella enterica, Shigella flexneri, Vibrio cholerae, Escherichia coli and Gram-positive, Listeria monocytogenes, but had no activities against different strains of gut lactobacilli. The mass spectrometric analysis showed that the enterocin 12a shared partial homology with 4Fe-4S domain-containing redox protein of E. faecalis R712. Further, enterocin 12a selectively inhibited the proliferation of various human cancer cell lines in a dose-dependent manner but not that of normal human peripheral blood mononuclear cells. Enterocin 12a-treated cancer cells showed apoptosis-like morphological changes. CONCLUSION: Enterocin 12a is a novel bacteriocin that has anticancer properties against human cell lines and negligible activity towards non-malignant cells. Therefore, it should be further evaluated for its anticancer potential in animal models.


Assuntos
Antibacterianos/farmacologia , Anticarcinógenos/farmacologia , Proliferação de Células/efeitos dos fármacos , Enterococcus faecium/química , Apoptose/efeitos dos fármacos , Hidrocarbonetos Aromáticos com Pontes/química , Hidrocarbonetos Aromáticos com Pontes/isolamento & purificação , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular/efeitos dos fármacos , Enterococcus faecium/metabolismo , Feminino , Humanos , Testes de Sensibilidade Microbiana , Vagina/microbiologia
5.
Biotechnol Appl Biochem ; 68(6): 1307-1312, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33059386

RESUMO

Tuberculosis, a global threat, is a highly infectious disease intensified by the emergence of drug-resistant strains. In tuberculosis disease spectrum, a typical situation is a dormant or latent phase where a person exposed to Mycobacterium tuberculosis has the reservoir of the disease that may or may not result in an active state. Existence of the dormant state is retarding the eradication of tuberculosis. Transcription of several genes helps M. tuberculosis to survive in nonreplicative mode. DosR transcription factor is the hallmark for this genesis. Diabetes mellitus is a predisposition factor leading to the development of tuberculosis and latent tuberculosis. High plasma insulin concentrations in the prediabetic state can increase the tuberculosis bacterium. On the other hand, antidiabetic drug metformin is known to reduce active tuberculosis disease when provided in combination with antitubercular therapy. However, the effect of the same on latent tuberculosis is still unknown. In the present work using tools of computational biology, we have tried to find the consequence of adding metformin in combination with rifampicin, a well-known antitubercular drug, on molecular mechanisms of latent tuberculosis. We have investigated whether metformin and rifampicin interact with DosR machinery or not. Our results indicate that if metformin-bound DosR-DNA complex binds with rifampicin, it will result in the conversion of active tuberculosis to latent tuberculosis.


Assuntos
Antituberculosos/farmacologia , Tuberculose Latente/tratamento farmacológico , Metformina/farmacologia , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Rifampina/farmacologia , Antituberculosos/química , Humanos , Tuberculose Latente/microbiologia , Metformina/química , Testes de Sensibilidade Microbiana , Rifampina/química
6.
Indian J Clin Biochem ; 36(1): 124-125, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33505137

RESUMO

Synergism in action of tucatinib and trastumab is reported in breast cancer management. However, its molecular basis is yet to be determined. In this context we attempted to provide an explanation at the molecular level by performing in silico experimentation and coupling its result with already available published observations. Our study will provide basis for planning further experimental study for unravelling the truth.

9.
J Gastrointestin Liver Dis ; 33(2): 245-253, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38944852

RESUMO

BACKGROUND AND AIMS: Colonoscopy has a vital role in the diagnosis of inflammatory bowel disease (IBD), as well as in the estimation of disease severity, monitoring response to therapy, and surveillance for neoplasia. We performed a systematic review of randomised trials of various bowel preparations for colonoscopy in IBD. METHODS: We searched various electronic databases (PubMed, Embase, and CENTRAL) for studies reporting about the use of various strategies to improve colonoscopy preparation in IBD. We included only randomized clinical trials (RCTs). A network meta-analysis was done using a frequentist approach to compare the effectiveness of various bowel preparations. The risk of bias was assessed using Cochrane risk of bias tool 2.0. Other outcome parameters like compliance, tolerance, acceptance, and adverse effects were assessed qualitatively. RESULTS: Seven RCTs reporting about 960 patients were included. On comparison with 4 liter (L) of poliethylen glycol (PEG), oral sulfate solution (OR=1.1, 95%CI: 0.65-1.86); PEG2L/Ascorbate (OR=0.98, 95%CI: 0.65-1.48); PEG1L (OR=1, 95%CI: 0.55-1.81); PEG2L plus bisacodyl (OR=1.08, 95%CI: 0.71-1.65); PEG4L plus simethicone (OR=1, 95%CI: 0.67-1.50); PEG/ sodium picosulfate and magnesium citrate (SPMC) 1.5L (OR=0.99, 95%CI: 0.55-1.78); SPMC 2L (OR=1.09, 95%CI: 0.61-1.97) had similar effectiveness. Three RCTs reported compliance, five RCTs reported tolerance, two studies reported patient acceptance and five RCTs reported data on the willingness of patients to repeat the procedure in the future. Low-volume preparations had better compliance, tolerance, acceptance, and willingness to repeat. No difference in additional outcomes like change in disease activity after colonoscopy, procedure-related outcomes after colonoscopy like cecal intubation rate, and change in electrolyte levels were found. CONCLUSION: Various bowel preparations had similar effectiveness in respect to colonoscopy preparation in IBD patients. Low-volume preparations have better compliance, tolerance, and acceptance. The systematic review was limited by a small number of included RCTs.


Assuntos
Catárticos , Colonoscopia , Doenças Inflamatórias Intestinais , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Colonoscopia/métodos , Catárticos/administração & dosagem , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/tratamento farmacológico
10.
Curr Res Microb Sci ; 6: 100220, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38303967

RESUMO

Aspergillus species encompass a variety of infections, ranging from invasive aspergillosis to allergic conditions, contingent upon the immune status of the host. In this spectrum, Aspergillus terreus stands out due to its emergence as a notable pathogen and its intrinsic resistance to amphotericin-B. The significance of Aspergillus-associated infections has witnessed a marked increase in the past few decades, particularly with the increasing number of immunocompromised individuals. The exploration of epidemiology, morphological transitions, immunopathology, and novel treatment approaches such as new antifungal drugs (PC945, olorofim) and combinational therapy using antifungal drugs and phytochemicals (Phytochemicals: quercetin, shikonin, artemisinin), also using immunotherapies to modulate immune response has resulted in better outcomes. Furthermore, in the context COVID-19 era and its aftermath, fungal infections have emerged as a substantial challenge for both immunocompromised and immunocompetent individuals. This is attributed to the use of immune-suppressing therapies during COVID-19 infections and the increase in transplant cases. Consequently, this review aims to provide an updated overview encompassing the epidemiology, germination events, immunopathology, and novel drug treatment strategies against Aspergillus terreus-associated infections.

11.
Am J Physiol Cell Physiol ; 305(5): C512-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23739181

RESUMO

Nonsteroidal anti-inflammatory drugs (NSAIDs; 1) are widely recommended for several acute and chronic conditions. For example, both indomethacin and aspirin are taken for pain relief. Aspirin is also used for prevention of myocardial infarction, and indomethacin can be administered orally or as a suppository for patients with rheumatoid disease and other chronic inflammatory states. However, use of NSAIDs can cause damage to the mucosal barrier surrounding the gastrointestinal (GI) tract, increasing the risk of ulcer formation. While microencapsulation of NSAIDs has been shown to reduce upper GI injury, sustained release in the lower GI tract and colon may cause epithelial erosion due to increased acidification. The use of suppositories has also been linked to rectal and lower GI bleeding. In this study, we investigated the role of NSAIDs aspirin and indomethacin on Na⁺/H⁺ exchanger (NHE) activity in rat colonic crypts. By comparing average rates of pH recovery between control and NSAID perfusion runs, we were able to determine that both aspirin and indomethacin increase hydrogen extrusion into the colonic lumen. Through treatment with 5-ethylisopropyl amiloride (EIPA), amiloride, and zoniporide dihydrochloride, we further demonstrated that indomethacin specifically enhances proton excretion through regulation of apical NHE-3 and NHE-2 and to a lesser extent on basolateral NHE-1 and NHE-4. Our results suggest that clinical exposure to NSAIDs may affect colonic tissue at the site of selected NHE isoforms, resulting in modulation of transport and barrier function.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Colo/efeitos dos fármacos , Indometacina/farmacologia , Trocadores de Sódio-Hidrogênio/metabolismo , Amilorida/análogos & derivados , Amilorida/farmacologia , Animais , Colo/metabolismo , Bloqueadores do Canal de Sódio Epitelial/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Guanidinas/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Transporte de Íons/efeitos dos fármacos , Masculino , Pirazóis/farmacologia , Ratos , Ratos Sprague-Dawley , Trocador 3 de Sódio-Hidrogênio , Trocadores de Sódio-Hidrogênio/agonistas , Trocadores de Sódio-Hidrogênio/genética
12.
Clin Chim Acta ; 551: 117584, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37805177

RESUMO

Population and food requirements are increasing daily throughout the world. To fulfil these requirements application of pesticides is also increasing. Organophosphorous (OP) and Organocarbamate (OC) compounds are widely used pesticides. These pesticides are used for suicidal purposes too. Both inhibit Acetylcholinesterase (AChE) and cholinergic symptoms are mainly used for the diagnosis of pesticide poisoning. Although the symptoms of the intoxication of OP and OC are similar, recent research has described different targets for OP and OC pesticides. Researchers believe the distinction of OP/OC poisoning will be beneficial for the management of pesticide exposure. OP compounds produce adducts with several proteins. There is a new generation of OP compounds like glyphosate that do not inhibit AChE. Therefore, it's high time to develop biomarkers that can distinguish OP poisoning from OC poisoning.


Assuntos
Acetilcolinesterase , Praguicidas , Humanos , Acetilcolinesterase/metabolismo , Praguicidas/toxicidade , Carbamatos/toxicidade
13.
Trop Doct ; 51(2): 244-246, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33241735

RESUMO

Glyphosate is a commonly used non-selective herbicide in agriculture and aquafarms. Gastrointestinal, respiratory and cardiovascular symptoms are predominant manifestations of glyphosate poisoning. Cardiac dysfunction should be kept as a possibility in patients presenting with shock, and the treatment is mainly supportive. We present such a case.


Assuntos
Glicina/análogos & derivados , Bloqueio Cardíaco/etiologia , Herbicidas/intoxicação , Choque Cardiogênico/etiologia , Tensoativos/intoxicação , Adulto , Glicina/intoxicação , Bloqueio Cardíaco/diagnóstico , Bloqueio Cardíaco/fisiopatologia , Bloqueio Cardíaco/terapia , Humanos , Masculino , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/fisiopatologia , Choque Cardiogênico/terapia , Glifosato
14.
In Silico Pharmacol ; 8(1): 5, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33214986

RESUMO

Hypertension is a public health concern. Low dose thiazide diuretics are known to effectively control blood pressure compared to that of other classes of antihypertensive drugs. In this context, we have performed an in-silico study and found that the two Sulphonamide Diuretics Hydrochlorothiazide and Indapamide bound the NADPH binding region of bacterial Dihydrofolate Reductase. Therefore, akin to Sulphonamide Antibiotics, Sulphonamide Diuretics may have antibiotic activity and thereby have the potential to modulate the gut microbiome in a way beneficial to vascular health. The in-silico experiment results were analyzed in the context of the relevant literature. We postulate that Sulphonamide Diuretics exert their antihypertensive role by modulating the gut microbiome, specifically by increasing butyrate-producing taxa in the gut. We recommend extending such work as it is plausible that Indapamide and other Sulphonamide Diuretics may be beneficial for both diabetes and hypertension.

15.
Indian J Tuberc ; 67(2): 253-256, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32553320

RESUMO

Tuberculosis is a health concern worldwide. The anti-tubercular drugs (particularly rifampicin) used for its management offers side effects like acute kidney injury. Creatinine, which is recognised as an important biomarker for the renal function, is commonly estimated with Jaffe's reaction (alkaline picrate reaction). However, interference of Jaffe's reaction with non-creatinine chromogens has been reported. In this context, we have checked the possibility of interference by Rifampicin and Isoniazid at therapeutic concentration with the Jaffe's reaction. Through in-silico study, we have studied the reaction prediction of picric acid with other chemicals/reactant (i.e. Rifampicin, Isoniazid and non-creatinine chromogens) in terms of confidence value. It is observed that the confidence value of reaction prediction between picric acid and INH and Rifampicin is much more than the same of pyruvic acid (non-creatinine chromogen). Further, we have checked the absorbance value of Jaffe's reaction mixture in aqueous media in the presence of both the drugs at 520nm. It is observed that the absorbance of alkaline picric acid increases with an increase in drug concentration. However, the increasing trend of absorbance is much more in the case of rifampicin compared to INH. It appears from our result rifampicin, and isoniazid has the potential to behave as non-creatinine chromogen and can give false positive creatinine results in Jaffe's reaction. Thus, it can cause misdiagnosis in patients consuming these drugs. We recommend study in the biological matrix for further validation of the result.


Assuntos
Antituberculosos/efeitos adversos , Compostos Cromogênicos/efeitos adversos , Creatinina/metabolismo , Reações Falso-Positivas , Isoniazida/efeitos adversos , Testes de Função Renal , Rifampina/efeitos adversos , Análise Espectral , Humanos , Indicadores e Reagentes , Picratos
16.
Clin Cancer Res ; 26(1): 193-205, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31615938

RESUMO

PURPOSE: Most World Health Organization (WHO) grade I meningiomas carry a favorable prognosis. Some become clinically aggressive with recurrence, invasion, and resistance to conventional therapies (grade 1.5; recurrent/progressive WHO grade I tumors requiring further treatment within 10 years). We aimed to identify biomarker signatures in grade 1.5 meningiomas where histopathology and genetic evaluation has fallen short. EXPERIMENTAL DESIGN: Mass spectrometry (MS)-based phosphoproteomics and peptide chip array kinomics were used to compare grade I and 1.5 tumors. Ingenuity Pathway Analysis (IPA) identified alterations in signaling pathways with validation by Western blot analysis. The selected biomarker was evaluated in an independent cohort of 140 samples (79/140 genotyped for meningioma mutations) by tissue microarray and correlated with clinical variables. RESULTS: The MS-based phosphoproteomics revealed differential Ser/Thr phosphorylation in 32 phosphopeptides. The kinomic profiling by peptide chip array identified 10 phosphopeptides, including a 360% increase in phosphorylation of RB1, in the 1.5 group. IPA of the combined datasets and Western blot validation revealed regulation of AKT and cell-cycle checkpoint cascades. RB1 hyperphosphorylation at the S780 site distinguished grade 1.5 meningiomas in an independent cohort of 140 samples and was associated with decreased progression/recurrence-free survival. Mutations in NF2, TRAF7, SMO, KLF4, and AKT1 E17K did not predict RB1 S780 staining or progression in grade 1.5 meningiomas. CONCLUSIONS: RB1 S780 staining distinguishes grade 1.5 meningiomas, independent of histology, subtype, WHO grade, or genotype. This promising biomarker for risk stratification of histologically bland WHO grade I meningiomas provides insight into the pathways of oncogenesis driving these outlying clinically aggressive tumors.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Meníngeas/patologia , Meningioma/patologia , Recidiva Local de Neoplasia/patologia , Fosfoproteínas/metabolismo , Proteínas Quinases/metabolismo , Proteínas de Ligação a Retinoblastoma/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Progressão da Doença , Seguimentos , Humanos , Fator 4 Semelhante a Kruppel , Espectrometria de Massas/métodos , Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo , Gradação de Tumores , Recidiva Local de Neoplasia/metabolismo , Prognóstico , Proteoma/análise , Proteoma/metabolismo , Fatores de Risco , Transdução de Sinais , Análise Serial de Tecidos/métodos
18.
Artigo em Inglês | MEDLINE | ID: mdl-29740541

RESUMO

Diarrheal disease caused by Vibrio cholerae is endemic in developing countries including India and is associated with high rate of mortality especially in children. V. cholerae is known to form biofilms on the gut epithelium, and the biofilms once formed are resistant to the action of antibiotics. Therefore agents that prevent the biofilm formation and disperse the preformed biofilms are associated with therapeutic benefits. The use of antibiotics for the treatment of cholera is associated with side effects such as gut dysbiosis due to depletion of gut microflora, and the increasing problem of antibiotic resistance. Thus search for safe alternative therapeutic agents is warranted. Herein, we screened the lactobacilli spp. isolated from the fecal samples of healthy children for their abilities to prevent biofilm formation and to disperse the preformed biofilms of V. cholerae and V. parahaemolyticus by using an in vitro assay. The results showed that the culture supernatant (CS) of all the seven isolates of Lactobacillus spp. used in the study inhibited the biofilm formation of V. cholerae by more than 90%. Neutralization of pH of CS completely abrogated their antimicrobial activities against V. cholera, but had negligible effects on their biofilm inhibitory potential. Further, CS of all the lactobacilli isolates caused the dispersion of preformed V. cholerae biofilms in the range 62-85%; however, pH neutralization of CS reduced the biofilm dispersal potential of the 4 out of 7 isolates by 19-57%. Furthermore, the studies showed that CS of none of the lactobacilii isolates had antimicrobial activity against V. parahaemolyticus, but 5 out of 7 isolates inhibited the formation of its biofilm in the range 62-82%. However, none of the CS dispersed the preformed biofilms of V. parahaemolyticus. The ability of CS to inhibit the adherence of Vibrio spp. to the epithelial cell line was also determined. Thus, we conclude that the biofilm dispersive action of CS of lactobacilli is strain-specific and pH-dependent. As Vibrio is known to form biofilms in the intestinal niche having physiological pH in the range 6-7, the probiotic strains that have dispersive action at high pH may have better therapeutic potential.


Assuntos
Biofilmes/crescimento & desenvolvimento , Cólera/prevenção & controle , Cólera/terapia , Lactobacillus/metabolismo , Probióticos/uso terapêutico , Vibrio cholerae/crescimento & desenvolvimento , Vibrio parahaemolyticus/crescimento & desenvolvimento , Adolescente , Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Linhagem Celular , Criança , Pré-Escolar , Cólera/microbiologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Humanos , Lactobacillus/classificação , Lactobacillus/isolamento & purificação
19.
Front Microbiol ; 9: 948, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867856

RESUMO

Cancer is the second leading cause of death worldwide and its incidence is expected to grow by almost 70% in the coming 2 decades. Recent microbiome studies in cancer mice models have shown that certain commensal bacteria play protective roles against cancer. Thus, the use of commensal microflora having anticancer activities for the treatment of cancer appears to be an attractive alternative therapeutic strategy. Lactic acid bacteria (LAB) form an integral component of commensal microflora in healthy individuals. As the vaginal ecosystem is enriched in LAB genera, we screened the vaginal LAB microflora of healthy women for their anti-proliferative abilities against various human cancer cell lines. The secreted metabolites of three enterococcal strains, Enterococcus hirae 20c, Enterococcus faecium 12a and L12b, out of 92 LAB isolates selectively inhibited the in vitro proliferation of various human cancer cell lines in a dose-dependent manner but had no activity against normal human peripheral blood monocytes. Further, proteinase K-treatment of the cell-free supernatant (CS) of all the three enterococci abrogated their anti-proliferative abilities, thereby showing the proteinaceous nature of the secreted metabolites in the CS. The microscopic examination of the cell lines showed that CS-treatment induced apoptosis-like morphological changes in the cancer cells. Further, the probiotic characters of the strains were studied, which showed that all the three strains had broad spectrum antimicrobial activities against various Gram-positive and Gram-negative pathogens, including Mycobacterium smegmatis. All the strains tolerated the gastric acidity and bile juice treatments, and had strong adhesive abilities to the colonic epithelial cell line HCT-15. Furthermore, none of the strains had any known secreted virulence factors or harbored virulence genes. This preliminary study highlights an important functional role of the commensal probiotic enterococcal strains E. hirae and E. faecium for the first time by demonstrating their anticancer properties that should be further tested in the in vivo mammalian models.

20.
Mater Sci Eng C Mater Biol Appl ; 83: 177-186, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29208277

RESUMO

A diopside based bioactive system with a nominal composition of xCuO-(45.55-x)CaO-29.44 SiO2-10.28P2O5-14.73 MgO (x=0,1,3 and 5mol%) has been prepared by sol gel technique in the laboratory. X-ray Diffraction, Fourier Transform Infra-Red and Raman Spectroscopy, Field Emission Scanning Electron Microscopy along with Energy Dispersive X-ray Analysis and pH studies have been undertaken on the prepared samples before and after dipping the samples in simulated body fluid. It has been observed that hydroxyapatite layer starts to form with in 24h during immersion in simulated body fluid. Degradation studies have also been employed to check the degradation behavior in Tris-HCl. Dynamic light scattering studies show that particles are mostly agglomerated and have an average size of 356nm. Zeta potential studies have been undertaken to check the surface charge and it has been estimated that samples carry negative charge when dipped in simulated body fluid. Negative surface charge may contribute to attachment and proliferation of osteoblasts. Samples have also shown the antimicrobial properties against the Vibro cholerae and Escherichia coli pathogens. To check the non-toxic nature of the samples, cell cytotoxic and cell culture studies have been undertaken using the MG-63 cell lines. Samples have shown good response with good percentage viability of the cells in the culture media and hence, provides friendly environment to the growth of cells. The particle size, bioactivity, negative values of zeta potential, antimicrobial properties and good cell viability indicate the potential of the synthesized compositions as possible candidates for bone repair applications.


Assuntos
Cobre/química , Compostos de Fósforo/química , Animais , Materiais Biocompatíveis/química , Linhagem Celular , Sobrevivência Celular , Durapatita/química , Humanos
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