Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
1.
Indian J Med Res ; 145(1): 97-101, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28574021

RESUMO

BACKGROUND & OBJECTIVES: Although polymicrobial infections involving both aerobic and anaerobic bacteria are very common in diabetic foot ulcers, in many centres of developing countries, anaerobes are rarely isolated due to technical difficulties. This can be overcome by using a new simple, innovative technique of a combination of candle combustion and use of acidified copper-coated steel wool, as reported here. METHODS: In-house developed method was used in a prospective clinico-microbiological study for anaerobes from randomly selected 43 patients with diabetic foot ulcers along with conventional method of anaerobic culture in GasPak system and aerobic culture by standard laboratory procedures. For primary isolation of anaerobes, Brucella blood agar supplemented with hemin (5 µg/ml) and menadione (1 µg/ml) was used. Antibiotic sensitivity tests were performed by the standard disc diffusion method for aerobes and E-test method for anaerobes. RESULTS: All the 43 samples were culture positive, of which aerobic Gram-negative bacteria (GNB) predominated, followed by Staphylococcus aureus, Enterococcus and diphtheroids. Anaerobes isolated from 21 samples were Peptostreptococcus, Bacteroides, Porphyromonas, Veillonella spp. and Clostridium perfringens by both GasPak and in-house developed and modified candle jar techniques. Imipenem and metronidazole were most sensitive while clindamycin, penicillin and cefoxitin were least sensitive drugs for anaerobes. Aerobic GNB were found to be multidrug resistant, especially to penicillin and cephalosporins. The most sensitive drug was piperacillin-tazobactam. INTERPRETATION & CONCLUSIONS: For isolation of anaerobes from clinical specimens such as diabetic foot ulcers, modified candle jar technique was found to be as reliable as GasPak system. This modified technique needs to be tested for many other clinical materials which are not yet evaluated.


Assuntos
Bactérias Anaeróbias/isolamento & purificação , Coinfecção/tratamento farmacológico , Coinfecção/microbiologia , Pé Diabético/microbiologia , Bactérias Anaeróbias/classificação , Bactérias Anaeróbias/efeitos dos fármacos , Bactérias Anaeróbias/patogenicidade , Cefalosporinas/uso terapêutico , Coinfecção/diagnóstico , Coinfecção/patologia , Pé Diabético/tratamento farmacológico , Pé Diabético/patologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistência a Múltiplos Medicamentos/genética , Humanos , Testes de Sensibilidade Microbiana , Penicilinas/uso terapêutico , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/patogenicidade
2.
Prep Biochem Biotechnol ; 46(1): 1-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25285655

RESUMO

Actinobacteria are promising source of a wide range of important enzymes, some of which are produced in industrial scale, with others yet to be harnessed. L-Asparaginase is used as an antineoplastic agent. The present work deals with the production and optimization of L-asparaginase from Actinomycetales bacterium BkSoiiA using submerged fermentation in M9 medium. Production optimization resulted in a modified M9 medium with yeast extract and fructose as carbon and nitrogen sources, respectively, at pH 8.0, incubated for 120 hr at 30 ± 2 °C. The crude enzyme was purified to near homogeneity by ammonium sulfate precipitation following dialysis, ion-exchange column chromatography, and finally gel filtration. The sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) revealed an apparent molecular weight of 57 kD. The enzyme was purified 95.06-fold and showed a final specific activity of 204.37 U/mg with 3.49% yield. The purified enzyme showed maximum activity at a pH 10.0 and was stable at pH 7.0 to 9.0. The enzyme was activated by Mn(2+) and strongly inhibited by Ba(2+). All these preliminary characterization suggests that the L-asparaginase from the source may be a tool useful to pharmaceutical industries after further research.


Assuntos
Actinomycetales/enzimologia , Asparaginase/isolamento & purificação , Asparaginase/metabolismo , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Temperatura
3.
Biochim Biophys Acta ; 1844(7): 1219-30, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24721562

RESUMO

Bacterial asparaginases (EC 3.5.1.1) have attracted considerable attention because enzymes of this group are used in the therapy of certain forms of leukemia. Class II asparaginase from Escherichia coli (EcA), a homotetramer with a mass of 138 kDa, is especially effective in cancer therapy. However, the therapeutic potential of EcA is impaired by the limited stability of the enzyme in vivo and by the induction of antibodies in the patients. In an attempt to modify the properties of EcA, several variants with amino acid replacements at subunit interfaces were constructed and characterized. Chemical and thermal denaturation analysis monitored by activity, fluorescence, circular dichroism, and differential scanning calorimetry showed that certain variants with exchanges that weaken dimer-dimer interactions exhibited complex denaturation profiles with active dimeric and/or inactive monomeric intermediates appearing at low denaturant concentrations. By contrast, other EcA variants showed considerably enhanced activity and stability as compared to the wild-type enzyme. Thus, even small changes at a subunit interface may markedly affect EcA stability without impairing its catalytic properties. Variants of this type may have a potential for use in the asparaginase therapy of leukemia.


Assuntos
Asparaginase/química , Asparaginase/metabolismo , Escherichia coli/enzimologia , Mutação/genética , Asparaginase/genética , Varredura Diferencial de Calorimetria , Dicroísmo Circular , Estabilidade Enzimática , Escherichia coli/genética , Cinética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Conformação Proteica , Desnaturação Proteica
4.
Arch Virol ; 160(11): 2749-61, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26280524

RESUMO

Chikungunya virus (CHIKV) has reemerged recently as an important pathogen, causing several large epidemics worldwide. This necessitates the development of better reagents to understand its biology and to establish effective and safe control measures. The present study describes the development and characterization of polyclonal antibodies (pAbs) against synthetic peptides of CHIKV non-structural proteins (nsPs; nsP1, nsP3 and nsP4). The reactivity of these pAbs was demonstrated by ELISA and Western blot. Additionally, in vitro infection studies in a mammalian system confirmed that these pAbs are highly sensitive and specific for CHIKV nsPs, as these proteins were detected very early during viral replication. Homology analysis of the selected epitope sequences revealed that they are conserved among all of the CHIKV strains of different genotypes, while comparison with other alphavirus sequences showed that none of them are 100% identical to the epitope sequences (except Onyong-nyong and Igbo Ora viruses, which show 100% identity to the nsP4 epitope). Interestingly, two different forms of CHIKV nsP1 and three different forms of nsP3 were detected in Western blot analysis during infection; however, further experimental investigations are required to confirm their identity. Also, the use of these antibodies demonstrated faster and enhanced expression profiles of all CHIKV nsPs in 2006 Indian outbreak strains when compared to the CHIKV prototype strain, suggesting the epidemic potential of the 2006 isolate. Accordingly, it can be suggested that the pAbs reported in this study can be used as sensitive and specific tools for experimental investigations of CHIKV replication and infection.


Assuntos
Anticorpos Antivirais/análise , Febre de Chikungunya/virologia , Vírus Chikungunya/isolamento & purificação , Proteínas não Estruturais Virais/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/imunologia , Western Blotting , Vírus Chikungunya/genética , Vírus Chikungunya/imunologia , Vírus Chikungunya/fisiologia , Ensaio de Imunoadsorção Enzimática , Epitopos/genética , Epitopos/imunologia , Dados de Sequência Molecular , Coelhos , Alinhamento de Sequência , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética , Replicação Viral
5.
J Biol Inorg Chem ; 19(8): 1377-84, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25338205

RESUMO

This work investigated a simple and versatile modification to a solid substrate to develop antibody recognition using nanoparticles. The new immobilized metal ion affinity adsorbent containing nanoparticles and hydrophilic resins is proposed here to improve the binding of antigen on its surface. The light-scattering properties of submicroscopic metal particles ranging from 100 to 120 nm in diameter were confirmed by scanning electron microscopy. We found that synthesized nanoparticles have an inherent enzyme mimetic activity similar to that found in natural peroxidases. The synthesized nanoparticles were coated with Salmonella typhi and Salmonella paratyphi antigens and were allowed to react with Salmonella-infected serum. Positive reactions were detected visually with the naked eye. The color changes of substrate (TMB) were observed even in 1:800 dilutions. This report helps in developing a specific immunoassay using nano-conjugated antigen for the rapid detection of S. typhi and S. paratyphi antibodies in infected serum.


Assuntos
Nanocompostos , Prata , Febre Tifoide/diagnóstico , Reações Antígeno-Anticorpo , Antígenos de Bactérias/imunologia , Humanos , Salmonella paratyphi A/imunologia , Salmonella typhi/imunologia , Prata/imunologia , Febre Tifoide/sangue , Febre Tifoide/imunologia
6.
Cell Biol Int ; 38(10): 1118-31, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24804954

RESUMO

Iron-based compounds possess the capability of inducing cell death due to their reactivity with oxidant molecules, but their specificity towards cancer cells and the mechanism of action are hitherto less investigated. A Fe(salen)Cl derivative has been synthesized that remains active in monomer form. The efficacy of this compound as an anti-tumor agent has been investigated in mouse and human leukemia cell lines. Fe(salen)Cl induces cell death specifically in tumor cells and not in primary cells. Mouse and human T-cell leukemia cell lines, EL4 and Jurkat cells are found to be susceptible to Fe(salen)Cl and undergo apoptosis, but normal mouse spleen cells and human peripheral blood mononuclear cells (PBMC) remain largely unaffected by Fe(salen)Cl. Fe(salen)Cl treated tumor cells show significantly higher expression level of cytochrome c that might have triggered the cascade of reactions leading to apoptosis in cancer cells. A significant loss of mitochondrial membrane potential upon Fe(salen)Cl treatment suggests that Fe(salen)Cl induces apoptosis by disrupting mitochondrial membrane potential and homeostasis, leading to cytotoxity. We also established that apoptosis in the Fe(salen)Cl-treated tumor cells is mediated through caspase-dependent pathway. This is the first report demonstrating that Fe(salen)Cl can specifically target the tumor cells, leaving the primary cells least affected, indicating an excellent potential for this compound to emerge as a next-generation anti-tumor drug.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Cloretos/química , Cloretos/farmacologia , Etilenodiaminas/química , Compostos Férricos/química , Compostos Férricos/farmacologia , Clorometilcetonas de Aminoácidos/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Fator Apoptótico 1 Ativador de Proteases/metabolismo , Linhagem Celular , Cloretos/síntese química , Citocromos c/metabolismo , Regulação para Baixo/efeitos dos fármacos , Etilenodiaminas/síntese química , Etilenodiaminas/farmacologia , Compostos Férricos/síntese química , Humanos , Células Jurkat , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Regulação para Cima/efeitos dos fármacos , Proteína de Morte Celular Associada a bcl/metabolismo
7.
Indian J Med Microbiol ; 43: 90-95, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36272878

RESUMO

PURPOSE: Adrenal histoplasmosis (AH) is an uncommon form of disseminated histoplasmosis caused by the dimorphic fungus Histoplasma capsulatum. Though, India is considered to be a non-endemic area for histoplasmosis, a high rise of AH cases is reported currently from various parts of India. Our study aimed to evaluate the current perspective of adrenal histoplasmosis in India by reviewing its clinical course, differential diagnosis, treatment, and mortality of our eleven confirmed cases of AH along with the review of authentic reported AH cases from India. MATERIAL &METHOD: Clinical materials were taken from radiologically suspected all 15 cases either with unilateral or bilateral adrenal enlargement, referred between 2018 and 2020 for microbiological investigations. Fungal stain and fungal culture along with other tests for possible differential diagnosis with AH were conducted. RESULT: Out of fifteen incidentaloma detected by radio-imaging, eleven cases of AH had been diagnosed in our hospital with yield of Rhodotorula spp. in one mimicking case. Nine of them were male (82%) and all were HIV nonreactive, which corroborates with the literature review. All of them had nonspecific clinical presentation of chronic abdominal pain, fever, weight loss, and anorexia. Four developed primary adrenal insufficiency, which are similar to the literature review (41%). On treatment with itraconazole and/or amphotericin B, all patients survived except one lost in follow-up. CONCLUSION: Male preponderance and non-compromised immune status are two special characteristics of most AH though reasons are ill understood. So, mycological investigations are to be done for every such case.


Assuntos
Histoplasmose , Humanos , Masculino , Feminino , Histoplasmose/diagnóstico , Histoplasmose/tratamento farmacológico , Histoplasmose/epidemiologia , Estudos Prospectivos , Centros de Atenção Terciária , Anfotericina B/uso terapêutico , Índia/epidemiologia , Antifúngicos/uso terapêutico
8.
J Exp Med ; 203(2): 349-58, 2006 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-16446379

RESUMO

Wild-type (WT) NOD.H-2h4 mice develop spontaneous autoimmune thyroiditis (SAT) when given 0.05% NaI in their drinking water, whereas B cell-deficient NOD.H-2h4 mice are SAT resistant. To test the hypothesis that resistance of B cell-deficient mice to SAT was due to the activity of regulatory CD4+CD25+ T (T reg) cells activated if autoantigen was initially presented on non-B cells, CD25+ T reg cells were transiently depleted in vivo using anti-CD25. B cell-deficient NOD.H-2h4 mice given three weekly injections of anti-CD25 developed SAT 8 wk after NaI water. Thyroid lesions were similar to those in WT mice except there were no B cells in thyroid infiltrates. WT and B cell-deficient mice had similar numbers of CD4+CD25+Foxp3+ cells. Mice with transgenic nitrophenyl-specific B cells unable to secrete immunoglobulin were also resistant to SAT, and transient depletion of T reg cells resulted in severe SAT with both T and B cells in thyroid infiltrates. T reg cells that inhibit SAT were eliminated by day 3 thymectomy, indicating they belong to the subset of naturally occurring T reg cells. However, T reg cell depletion did not increase SAT severity in WT mice, suggesting that T reg cells may be nonfunctional when effector T cells are activated; i.e., by autoantigen-presenting B cells.


Assuntos
Linfócitos B/patologia , Linfopenia/genética , Linfopenia/imunologia , Linfócitos T Reguladores/imunologia , Tireoidite Autoimune/imunologia , Tireoidite Autoimune/prevenção & controle , Animais , Anticorpos Monoclonais/administração & dosagem , Linfócitos B/imunologia , Linfócitos B/metabolismo , Células Cultivadas , Feminino , Fatores de Transcrição Forkhead/metabolismo , Imunoglobulinas/deficiência , Contagem de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Receptores de Interleucina-2/biossíntese , Receptores de Interleucina-2/imunologia , Linfócitos T Reguladores/metabolismo , Tireoidite Autoimune/genética
9.
Cureus ; 14(11): e31728, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36569693

RESUMO

Background Dermatophytosis is a public health concern in tropical countries. In India, a scalable number of dermatophytosis cases from multiple states are reported. In the eastern part of India, very few studies were published assessing the clinicomycological profiles of patients. Hence, we conducted this study to ascertain the clinicomycological profile of patients suffering from dermatophytosis with special reference to associated socio-environmental factors. Materials and methods This cross-sectional observational study was conducted in a tertiary care hospital situated in Bihar state of India from January 2021 to December 2021. We included a total of 330 patients of all age groups who were clinically diagnosed with superficial mycosis from the Department of Dermatology and sent for investigations to the Department of Microbiology. The collected specimens from the lesions were prepared with wet potassium hydroxide and examined under the microscope. Then, the specimens were inoculated and incubated at 25°C for up to four weeks. Fungal isolates were identified by gross appearance and microscopy if growth was observed. Results Among the 330 patients, 186 (56.4%) were males and 144 (43.6%) were females. The majority of the patients (54.5%) were from the low socioeconomic group and living in overcrowded places. Direct microscopy was positive in 198 (60%) patients, and culture was positive in 68 (20.61%) patients. The majority of the patients who were found positive in direct microscopy were from the age group of 21-30 years (39.9%), followed by 1-10 years (25.25%). A total of 92 (46.4%) cases were of tinea capitis, followed by 68 (34.3%) patients of tinea corporis. Trichophyton was the predominant fungus isolated, and Trichophyton mentagrophytes was the most common species (52.6%). Conclusion Tinea capitis was the most common provisionally diagnosed dermatophytosis in our tertiary care hospital in Bihar, an Indian state in its eastern zone. Low socioeconomic status and poor personal hygiene were the factors associated with the high prevalence of dermatophyte infections in this region of India. A detailed analysis of all these epidemiological factors is needed to limit the prevalence of dermatophytosis in tropical regions.

10.
Sci Rep ; 11(1): 11610, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078983

RESUMO

Following access into the cell, colloidal silver nanoparticles exhibit generalized cytotoxic properties, thus appear as omnipotent microbicidal, but not suitable for systemic use unless are free of toxic effects on host cells. The AgNP-Serum-18 when prepared from silver nitrate, using dextrose as reducing and group-matched homologous serum as a stabilizing agent, selective endocytosis, and oxidative stress-dependent bio-functional damages to the host are mostly eliminated. For their bio-mimicking outer coat, there is the least possibility of internalization into host cells or liberation of excess oxidants in circulation following interaction with erythrocytes or vascular endothelial cells. The presence of infection-specific antibodies in the serum can make such nano-conjugates more selective. A potent antimicrobial action and a wide margin of safety for mammalian cells in comparison with very similar PVA-capped silver nanoparticles have been demonstrated by the in-vitro challenge of such nanoparticles on different microbes, human liver cell-line, and in-vivo study on mice model. This may open up wide-range therapeutic prospects of colloidal nanoparticles.


Assuntos
Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Nitrato de Prata/farmacologia , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Antibacterianos/síntese química , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Coloides , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Nanopartículas Metálicas/ultraestrutura , Camundongos , Testes de Sensibilidade Microbiana , Especificidade de Órgãos , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
11.
Chem Commun (Camb) ; 57(39): 4851-4854, 2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-33870381

RESUMO

An oxo(corrolato)chromium(v) complex selectively kills leukemia cells. However, this complex did not induce cell death in primary non-cancer cells. It has been observed that oxo(corrolato)chromium(v) complex induced cell death is associated with DNA damage. Interestingly, the DNA in primary cells largely remained unaffected. DNA isolated from normal and cancerous cell lines also follows similar trends. A chemical reductant, DTT, was used to probe the mechanism of DNA damage. However, it does not show any additive effect on DNA damage.


Assuntos
Antineoplásicos/farmacologia , Cromo/farmacologia , Complexos de Coordenação/farmacologia , DNA de Neoplasias/efeitos dos fármacos , Porfirinas/farmacologia , Animais , Antineoplásicos/química , Morte Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromo/química , Complexos de Coordenação/química , Dano ao DNA , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Estrutura Molecular , Porfirinas/química
12.
PLoS One ; 14(3): e0214192, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30917172

RESUMO

Adherence of the microorganism to submerged solid surfaces leads to biofilm formation. Biofilm formation modifies the surfaces in favor of bacteria facilitating the survival of the bacteria under different stressed conditions. On the other hand, the formation of biofilm has a direct adverse economic impact in various industries and more importantly in medical practices. This adherence is the reason for the failure of many indwelling medical devices. Surface biofilm adhesion is the key to biofilm growth and stability. Hence this adhesion needs to be substantially lowered to inhibit biofilm stability. Both chemical and physical properties of the surface influence biofilm formation and modulating these properties can control this formation. In this study, we have investigated the effect of Hydrofluoric acid (HF), at a specific concentration as an etchant, on the surface morphology of substrates and the growth of biofilms of Pseudomonas aeruginosa. and Staphylococcus aureus. We find that the bacterial counts on the etched surfaces undergo a periodic increase and decrease. This, on one hand, shows the close correlation between the biofilm growth and the particular roughness scale, and on the other hand, explains the existing contradictory results regarding the effects of etching on substrate roughness and biofilm growth. We propose a simple model of a sequence of hole formation, hole expansion and etching away of the hole walls to form a new, comparatively smooth surface, coupled with the preferential accumulation of bacteria at the hole edges, to explain these periodicities.


Assuntos
Biofilmes/crescimento & desenvolvimento , Vidro/química , Ácido Fluorídrico/química , Pseudomonas aeruginosa/fisiologia , Staphylococcus aureus/fisiologia , Propriedades de Superfície
13.
Indian J Otolaryngol Head Neck Surg ; 71(Suppl 3): 1821-1826, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31763253

RESUMO

Conidiobolomycosis is a rare mycotic disease caused by Conidiobolus coronatus. Very few cases have been reported in English literature. Often it is clinically misdiagnosed as soft tissue tumour. A prospective case study was done from 2006 to 2015 in a tertiary care hospital of West Bengal, India. The objectives of our study were to describe the epidemiological and clinical features and treatment of Conidiobolomycosis to prevent disfigurement. Patients clinically suspected to be suffering from Conidiobolomycosis were subjected to biopsy followed by histopathological and mycological examinations. Then they were treated with oral saturated solution of potassium iodide along with other drugs. Total six cases were histopathologically proved to be suffering from Conidiobolomycosis. Fungus was isolated and identified in one case. Complete resolution was seen in five patients. Conidiobolomycosis should be brought into mind as differential diagnosis of subcutaneous swelling in the rhinofacial region.

14.
Sci Rep ; 8(1): 7118, 2018 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-29740052

RESUMO

Naive T cells are known to express the modest level of TLR4 while it is known to go down during TCR activation. However, information towards the requirement of TLR4 signaling during TCR or mitogenic activation of naive wild-type T cells remains scanty. Here we have investigated the endogenous functional expression of TLR4 in naive mice T cells during TCR and mitogenic stimulation in presence of VIPER peptide (VP), an established inhibitor of TLR4 signaling. As expected we found that TLR4 expression goes down during TCR and mitogenic activation. Interestingly, we observed that VP treatment restores TLR4 expression on those activated T cells. Moreover, VP was found to regulate such activation of naive T cell as evident by reduction of CD25, CD69 expression, effector cytokines (IL-2, IFN-γ, TNF) production, T cell proliferation and down-regulation of T cell activation-dependent Fas (CD95), FasL (CD95L) expression. Together, our current observation highlights a possible requirement of TLR4 responses in T cells, which might have possible implication towards the pathogenic acute phase activation of naive T cells.


Assuntos
Proliferação de Células/genética , Linfócitos T/efeitos dos fármacos , Receptor 4 Toll-Like/genética , Proteínas Virais/farmacologia , Animais , Antígenos CD/genética , Antígenos de Diferenciação de Linfócitos T/genética , Proliferação de Células/efeitos dos fármacos , Citocinas/efeitos dos fármacos , Citocinas/genética , Proteína Ligante Fas/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Subunidade alfa de Receptor de Interleucina-2/genética , Lectinas Tipo C/genética , Camundongos , Transdução de Sinais/efeitos dos fármacos , Linfócitos T/metabolismo , Receptor 4 Toll-Like/antagonistas & inibidores , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/efeitos dos fármacos , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética , Proteínas Virais/química
15.
J Lab Physicians ; 9(2): 125-131, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28367029

RESUMO

INTRODUCTION: Treatment refractory chronic recurrent infections mean those chronic infections which recur by same causal agents with similar drug responsiveness after apparent relief following full course of recommended antimicrobial management. MATERIALS AND METHODS: Fifty different samples were collected from patients with chronic surgical site infections, laparoscopic port site infections, anal fistula, mesh hernioplasty, chronic dacryocystitis, chronic osteomyelitis, and chronic burn wounds. Samples were processed for culture, identification, antibiotic sensitivity testing using standard microbiological techniques. Biofilm (BF) forming capacity for aerobic organisms were tested by tissue culture plate method. Those for anaerobes and atypical mycobacteria were studied by a novel method using atomic force microscopy (AFM). In vivo BF colonization in lacrimal mucosae of chronic dacryocystitis, patients were studied from histopathological sections by Gram staining, H and E, and fluorescent in situ hybridization (FISH). RESULTS: Out of fifty different samples, sixty-three isolates were obtained in pure culture as follows: Staphylococcus aureus (25.39%), Escherichia coli (14.28%), Klebsiella pneumonia (14.28%), Mycobacterium abscessus (12.69%), Citrobacter spp. (9.52%), Bacteroides fragilis (6.3%), Pseudomonas aeruginosa (4.7%), Proteus spp. (4.7%), Staphylococcus epidermidis (3.1%), Enterobacter spp. (1.5%), Morganella morganii (1.5%), and Peptostreptococcus spp. (1.5%). Among the isolates, 74% were found to be BF producers in the following frequency: P. aeruginosa 100%, S. epidermidis 100%, B. fragilis 100%, Klebsiella spp. 88.88%, S. aureus 81.25%, M. abscessus 75%, Citrobacter spp. 83.33%, Proteus spp. 66.66%, E. coli spp. 33.33%, and Enterobacter spp. 0%. CONCLUSION: AFM has been proven to be a useful method for detection of in vitro grown BF including those for anaerobes and atypical Mycobacteria. In vivo BF detection becomes possible by FISH. S. aureus was the most common isolate. Among the aerobic isolates, P. aeruginosa and S. epidermidis were found to be the most common BF producers. Atypical mycobacteria were also found to be BF producers. Diagnosis of BF s in chronic infections significantly changes the management strategy as these infections can no longer be dealt simply with antibiotics alone but require mechanical removal of the foci along with antibiotic coverage for complete cure.

16.
Indian J Tuberc ; 64(3): 178-182, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28709485

RESUMO

INTRODUCTION: Rapidly growing non-tuberculous mycobacteria (NTM) are hazardous cause of post-operative soft tissue infection leading to nosocomial outbreaks following various surgical procedures, especially laparoscopic surgeries using heat sensitive, non-autoclavable surgical instruments. METHODOLOGY: Surgery department of our hospital noticed increase in rate of post-laparoscopic abdominal port site infection (PSI) and informed the Microbiology Department. A prospective investigational study of defined cases with the aim of source tracing and formulation of infection control measures was initiated. Pus or wound scrapings were collected and processed for aerobic, anaerobic bacteria and Mycobacterium, both by staining and culture. Environmental samples were collected from laparoscopic instruments, and different parts of operation theatre (OT). Mycobacterial isolates were speciated by line probe assay. All the cases were treated with clarithromycin and ofloxacin±amikacin. RESULTS: Among 15 cases of PSI, 11 patients had undergone laparoscopic cholecystectomy, 3 had laparoscopic mesh hernioplasty and one had laparoscopic orchidopexy. Of the 13 pus/discharge specimens examined, 11 revealed growth of NTM. All the isolates were identified as Mycobacterium abscessus by line probe assay. Scraping of biofilm from the disinfectant tray also produced growth of the same organism. Plastic trays used for disinfectants were replaced with metal trays and instructed to do mechanical scrubbing before autoclaving at regular interval. No similar PSI cases were notified after those measures were taken, till date. CONCLUSIONS: This study has shown the need of culture and identification of pathogens causing persistent post surgical wound infections and illuminated importance of rapid source tracing in resource constraint situation which could control outbreak.


Assuntos
Biofilmes/crescimento & desenvolvimento , Infecção Hospitalar/microbiologia , Laparoscopia/efeitos adversos , Infecções por Mycobacterium não Tuberculosas/microbiologia , Mycobacterium abscessus/isolamento & purificação , Infecção da Ferida Cirúrgica/microbiologia , Infecção Hospitalar/prevenção & controle , Contaminação de Equipamentos/prevenção & controle , Humanos , Controle de Infecções/métodos , Laparoscopia/instrumentação , Infecções por Mycobacterium não Tuberculosas/prevenção & controle , Estudos Prospectivos , Infecção da Ferida Cirúrgica/prevenção & controle
17.
Int J Mycobacteriol ; 6(1): 34-37, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28317802

RESUMO

BACKGROUND: Port-site infection (PSI) is a prevailing, chronic, nagging, treatment refractory complication of laparoscopic surgery (LS). It neutralizes the advantages of minimally invasive surgery and increases morbidity, treatment cost of patient, leading to loss of confidence on operating surgeon. PSIs are preventable with appropriate preoperative, intraoperative, and postoperative measures. Atypical mycobacterium is most commonly associated with nonhealing postlaparoscopic wound infections, causing outbreaks or sporadic cases worldwide. PURPOSE: We retrospectively studied the occurrence of nontuberculous mycobacterium (NTM) from PSIs following LS that did not respond to antibiotics used for pyogenic infections and having sterile routine aerobic cultures and their antimicrobial susceptibility pattern to guide proper management. METHODS: The study was done in a tertiary care hospital of Eastern India over a 1-year period which included PSI cases with delayed onset not responding to antibiotics, following different types of LS. Pus/discharge from 32 patients was collected and examined for isolation and identification of the causative agents. Gram stain and Ziehl-Neelsen staining methods were used for direct examination. Culture media included blood agar, Robertson's cooked meat broth, MacConkey agar, and Lowenstein-Jensen medium. Isolates from the cases were identified using biochemical tests or molecular methods and studied the antimicrobial susceptibility pattern by the standard microbiologic procedures. RESULTS: Mycobacterium abscessus (13) and Mycobacterium fortuitum (2) were isolated from 15 serosanguinous drainage obtained from 32 cases by routine microbiological techniques. All isolates analyzed for antimicrobial susceptibility pattern were highly sensitive to clarithromycin (93.3%), amikacin (93.3%), and imipenem (80%) but were variable to ciprofloxacin, ofloxacin, and linezolid. CONCLUSIONS: Our present study shows frequent association of NTM with laparoscopic port-site nonhealing chronic infection or wound dehiscence. Although direct microscopy can give us a clue to diagnosis, culture isolation is required for speciation and antimicrobial susceptibility testing, which helps formulate therapeutic regimen.


Assuntos
Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/crescimento & desenvolvimento , Micobactérias não Tuberculosas/isolamento & purificação , Infecção da Ferida Cirúrgica/microbiologia , Adolescente , Adulto , Idoso , Antibacterianos/farmacologia , Criança , Ciprofloxacina/farmacologia , Feminino , Humanos , Imipenem/farmacologia , Índia/epidemiologia , Laparoscopia/efeitos adversos , Linezolida/farmacologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Mycobacterium abscessus/efeitos dos fármacos , Mycobacterium abscessus/crescimento & desenvolvimento , Mycobacterium abscessus/isolamento & purificação , Mycobacterium fortuitum/efeitos dos fármacos , Mycobacterium fortuitum/crescimento & desenvolvimento , Mycobacterium fortuitum/isolamento & purificação , Micobactérias não Tuberculosas/efeitos dos fármacos , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/epidemiologia , Centros de Atenção Terciária , Adulto Jovem
18.
J Neuroimmunol ; 176(1-2): 187-97, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16730380

RESUMO

Intravenous immunoglobulin (IVIG) administration has been beneficially used in the treatment of several autoimmune disorders including myasthenia gravis (MG), although its mechanism of action is still not clear. To study the optimal conditions of IVIG treatment and delineate its mechanism of action we established a suitable model in rat experimental autoimmune MG (EAMG). We show that IVIG has a suppressive effect on the clinical symptoms of ongoing EAMG that is associated with decreased AChR-specific cellular and humoral immune reactivity. Costimulatory factors and cytokine profile analyses suggest that IVIG immunomodulation in EAMG involves suppression of B and Th1-type T cell responses with no generation of T-regulatory cells. Our data contribute to the understanding of the immunological mechanisms underlying IVIG treatment in MG and in other autoimmune disorders.


Assuntos
Imunoglobulinas Intravenosas/uso terapêutico , Miastenia Gravis Autoimune Experimental/prevenção & controle , Animais , Feminino , Imunoglobulina G/sangue , Imunoglobulina G/classificação , Interleucina-10/fisiologia , Interleucina-4/fisiologia , Ativação Linfocitária , Miastenia Gravis Autoimune Experimental/imunologia , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos Lew , Receptores Colinérgicos/imunologia , Receptores de Interleucina-2/genética , Fator de Crescimento Transformador beta/genética
19.
J Clin Diagn Res ; 10(6): DD06-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27504288

RESUMO

Morganella morganii is a member of Enterobacteriaceae family, whose natural habitat is the human gastrointestinal tract. It rarely causes infection alone and is generally encountered in immunosuppressed patients. Osteoarticular pathologies are not commonly observed with Morganella morganii and infections by it have high mortality rate. Biofilm colonization is a causative factor behind the chronicity and/or refractoriness of certain infections. Biofilms colonize on inert medical devices, prosthesis, fibrosed tissues, sinus tracts as well as dead bones as in case of chronic osteomyelitis. Morganella morganii is not a common pathogen to produce biofilm. In this case report, we present a 56-year-old male patient with chronic osteomyelitis of right proximal tibia caused by biofilm producing strain of Morganella morganii, following trauma.

20.
Indian J Dermatol ; 61(5): 580, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27688460

RESUMO

We report two cases of chronic progressive disseminated histoplasmosis with unusual and rare clinical picture in a patient with no underlying risk factor. One 50-year-old male, presented with hoarseness of voice, chronic cough, with a history of nonresponding anti-tubercular therapy, revealed mucocutaneous lesions on examination. Fungating vocal cord lesions were visualized on bronchoscopy, raised suspicion of carcinoma. The second case, a 22-year-old female, referred to hospital with suspected vasculitis, with complaints of "off and on" fever with decreased oral intake, arthralgia, who later developed generalized nodular skin eruptions. On investigation, human immunodeficiency virus test was found to be negative in both the cases. Histopathological findings of skin biopsy, adrenal and bone marrow aspirates raised suspicion, whereas fungal cultures confirmed Histoplasma infection. Although diagnosis was delayed, but both of them were successfully treated with amphotericin B.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA