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Background: Malignant tumors of the trachea are rare. A multimodality treatment approach is often necessary. Outcomes of radical non-surgical approaches are sparse. Radiation combined with sequential or concurrent chemotherapy is an important treatment option. Materials and Methods: We present an analysis of outcomes using modern radiotherapy and chemotherapy for tracheal tumors. Results: Radiation dose escalation using modern techniques is of benefit for these tumors. The results with chemotherapy are encouraging. Conclusions: Radiation plays a distinct role and should be a part of treatment for these tumors. The role of chemotherapy needs to be studied further.
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Quimiorradioterapia/métodos , Quimiorradioterapia/tendências , Humanos , Quimiorradioterapia/estatística & dados numéricos , Neoplasias da Traqueia/tratamento farmacológico , Neoplasias da Traqueia/radioterapiaRESUMO
Background: Different species of frogs had been used by many researchers for evaluation of analgesic drugs e.g., Rana pipiens and African claw frog. In our study, we used Rana tigrina, which was never used for evaluation of analgesic activity of drugs. So by doing this project, we judged usefulness of R. tigrina to evaluate analgesic drugs. Methods: Animals used were R. tigrina of either sex weighing 100-150 g. Glass flask with porous platform was used for observation of frog. All groups were treated with 4% NaCl solution S.C. on abdomen). Characteristic parameter i.e., number of eye blinkings (this parameter was observed during the pilot study after 4% NaCl S.C. injection on lower third of frogs abdominal wall) were observed before and after drug administration. Each observation was for 5 mins. Centrally and periphrally acting drugs effect was tested on the number of blinks and buccal oscillations. Results: Centrally acting drug inhibit rise in number of eye blinkings and buccal oscillation significantly. Piroxicam diclofenac sodium and ketoprofen decreased rise in number of blinks; but, it was not significant as compared with control. Conclusion: This animal may be used alternative to existing methods of evaluating analgesics in Indian setup.
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Background: Barringtonia racemosa (B. racemosa) is used medicinally in treatment of diarrhoea, asthma, coughs, jaundice. It is also used as an analgesic and antipyretic. This plant has also significant anti-tumor activity. However, systematic evaluation of its immunomodulatory effects has not been reported. In present study the hydroalcoholic extract of fruits of B. racemosa has been evaluated for its immunomodulatory properties in animal models. Methods: Extract of Fruits of B. racemosa was prepared from fruit powder and methanol by macerations and filtration. Healthy albino Wistar rats of either sex having 110-160 g body weight were used for this study. 1. Delayed type hypersensitivity reaction (DTH) using Sheep red blood cells (SRBCs): After immunization with SRBC effect of cyclophosphamide and hydroalcoholic extract of B. racemosa was seen on paw volume changes in rats challenged with SRBC by using digital Plethysmometer. 2. Humoral antibody response to SRBC: Animas were immunized with SRBC and treated with cyclophosphamide and hydroalcoholic extract of B. racemosa. Serum of these animals was observed for haemagglutination titer. Results: Fruits extract at the dose of 5 mg/kg i.p. showed significant decrease in DTH response as compared to that of control group animals. However, the effect of extract was less potent as compared to that of cyclophosphamide treated group. In haemagglutination titer assay, antibody titer in case naïve control, SRBC treated, cyclophosphamide treated and extract treated groups was 1:1, 1:32, 1:8 and 1:16 respectively. Conclusions: The hydroalcoholic extract of this fruits was found to inhibit SRBCs induced DTH in rats. Similarly, SRBCs induced antibody titer was also reduced.
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BACKGROUND: In upper abdominal malignancies (UAM), due to the presence of multiple inhomogeneous tissues, a wedge-based conformal treatment planning results in high-dose regions inside the target volume. AIM: This study was designed to explore the feasibility of using a field-in-field (FIF) technique in different UAM and its efficacy in reducing the high-dose regions. MATERIALS AND METHODS: Twelve patients of UAM (which included malignancies of the gastroesophageal junction, stomach, gall bladder, and pancreas) were selected for this study. Computed tomography (CT) scans were performed and three-dimensional conformal wedge plans were generated for all the cases. The same plan was copied with the wedges removed and a FIF plan was generated. The two plans were compared for mean, maximum, and median doses; dose received by 2% (D2) and 98% (D98) of the target volume; volume receiving> 107% (V > 107%) and < 95% (V Statistical Analysis: Statistical analysis was performed with SPSS, version 10.0. RESULTS: For all the cases, the FIF technique was better than wedge-based planning in terms of maximum dose, D2, V > 107%, and CI; there was a statistically significant reduction in monitor units. With regard to doses to critical structures, there was marginal dose reduction for the kidneys and spinal cord with FIF as compared to wedge-based planning. CONCLUSION: The FIF technique can be employed for UAM in place of wedge-based conformal treatment plans.
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Neoplasias Abdominais/radioterapia , Relação Dose-Resposta à Radiação , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/instrumentação , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional , Tomografia Computadorizada por Raios XRESUMO
AIM: The aim of our study was to compare the two standard treatment approaches in muscle invasive carcinoma of urinary bladder--radical cystectomy and chemo radiation. MATERIALS AND METHODS: Transitional cell carcinoma (TCC) of bladder of stages, T2 to T4, N0/N1/N2 and M0 were included in the study. Patients were allotted to two arms of the study. Arm A consisted of radical cystectomy. Adjuvant CMV chemotherapy was given for T3/T4 or Node positive disease only. Arm B received 2 cycles of neoadjuvant CMV chemo therapy followed by concurrent chemo radiation. RESULTS: Forty-four patients were recruited into the study. Thirty patients in the surgical arm and 13 patients in the chemo radiation arm. The actuarial two-year survival rate in surgical arm is 56% while in chemo radiation arm it is 54%. There was no statistically significant difference in disease-free survival also between the two groups. CONCLUSION: Chemo radiation yielded equivalent survival results with radical cystectomy. So it is worth giving preference to chemo radiation that will give a better quality of life for the patient.
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Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/radioterapia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Musculares/radioterapia , Invasividade Neoplásica , Resultado do Tratamento , Neoplasias da Bexiga Urinária/patologiaRESUMO
PURPOSE: This study was mainly framed to study the difference in tumor volumes as seen on computed tomography (CT) and magnetic resonance (MR) and their significance in planning. MATERIALS AND METHODS: Twenty-five patients with brain tumor of different diagnoses who underwent stereotactic radiotherapy were included in this study. CT and MR imaging was done for all the patients with 2.5 mm slice thickness. The CT tumor volume and MR tumor volume were measured and compared with each other. The center of mass (CM) of the tumor volume delineated on CT and MR were computed and the shift between the two CMs was determined. RESULTS: The mean and median volume of the tumor as measured from MR scans was 19.67 cc +/- 13.73 and 16.13 cc (range: 3.25 cc-50.37 cc). Similarly, the mean and median volume of the tumor as measured from CT scans was 15.05 cc +/- 10.13 and 11.63 cc (range: 3.0 cc-36.25 cc) respectively. The mean and median CM shift between CT and MR was 5.47 mm and 5.21 mm respectively. CONCLUSION: The study demonstrates that MR is an indispensable imaging modality in radiotherapy for planning brain tumors.
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Neoplasias Encefálicas/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Radiocirurgia , Tomografia Computadorizada por Raios XRESUMO
Cranoifacial microsomia is an unique clinical presentation of '1st and 2nd arch syndrome' with asymmetrical craniofacial development alongwith conductive hearing loss. A series of 11 patients (4 males, 7 females) is presented which include two patients of 'Goldenhar's variant' with epibulbar dermoids. Two patients had no response on pure tone audiometry (blank audiograms) and underwent CT scan of temporal bone which revealed 'Michel's aplasia' (complete labyrinthine agenesis), rarely reported in the literature.
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BACKGROUND & OBJECTIVES: Poor bioavailability of rifampicin (R) in combination with other anti-tuberculosis drugs such as isoniazid (H), pyrazinamide (Z), and ethambutol (E) is a subject of much concern for the last few decades. This could be due to an interaction between R and other drugs. An investigation was therefore undertaken to examine the bioavailability of R in the presence of H, Z and E or a combination of the three drugs. METHODS: The study included eight healthy volunteers, each being investigated on four occasions at weekly intervals once with R alone and with three of the four combinations on the three remaining occasions. A partially balanced incomplete block design was employed and the allocation of R or the drug combinations was random. Plasma concentrations of R at intervals up to 12 h were determined by microbiological assay using Staphylococcus aureus as the test organism. The proportion (%) dose of R as R plus desacetyl R (DR) in urine excreted over the periods 0-8 and 8-12 h was also determined. Bioavailability was expressed as an index (BI) of area under time concentration curve (AUC) calculated from the plasma concentrations or proportion of dose of R excreted as R plus DR in urine with the combinations to that with R alone. RESULTS: The bioavailability indices based on AUC were 0.96 with RE, 0.76 with RH, 1.08 with RZ and 0.65 with REHZ. The indices based on urine estimations (0-8 h) were similar, the values being 0.94, 0.84, 0.94 and 0.75, respectively. A second investigation revealed that the decrease of bioavailability of R with H was not due to the excipients present in H tablets. INTERPRETATION & CONCLUSION: Isoniazid alone or in combination with E and Z reduces the bioavailability of R. Urinary excretion data offer a simple and non invasive method for the assessment of bioavailability of R.
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Adolescente , Adulto , Antibióticos Antituberculose/farmacocinética , Área Sob a Curva , Peso Corporal , Etambutol/farmacologia , Humanos , Isoniazida/farmacologia , Masculino , Pessoa de Meia-Idade , Pirazinamida/farmacologia , Rifampina/farmacocinética , Staphylococcus aureus/metabolismo , Fatores de TempoRESUMO
Tuberculosis (TB) continues to be a major health problem in India. There has been no perceptible change in the epidemiology of TB since the National Sample Survey 1956-57. Detection of cases has been low over the years since the inception of National TB control programme in 1962 due to passive case finding and high drop out rates among sputum positive patients. Shortening the course of chemotherapy with regimens containing bactericidal and sterilising drugs helped in improving the treatment adherence of patients and cutting down the chain of transmission substantially. Further it is advisable to implement properly the directly observed short course treatment (DOTS) as per WHO guidelines to prevent the development of multidrug resistant TB (MDRTB). Proper management of RNTCP and prevention of MDRTB are all the more important in areas where there is high prevalence of HIV/AIDS co-infected with TB. New vaccine development is also a priority area for research. There is an urgent need for health systems research built into the ongoing programme with proper managerial inputs.
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Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Antituberculosos/efeitos adversos , Países em Desenvolvimento , Quimioterapia Combinada , Previsões , Humanos , Índia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Pulmonar/prevenção & controleRESUMO
A total of 446 lymph node biopsy specimens showing histological evidence of tuberculosis were classified into four groups based on the organization of the granuloma, the type and numbers of participating cells and the nature of necrosis. These were, hyperplastic (22.4%)--a well-formed epithelioid cell granuloma with very little necrosis, reactive (54.3%)--a well-formed granuloma consisting of epithelioid cells, macrophages, lymphocytes and plasma cells with fine, eosinophilic caseation necrosis, hyporeactive (17.7%)--a poorly organized granuloma with macrophages, immature epithelioid cells, lymphocytes and plasma cells and coarse, predominantly basophilic caseation necrosis and nonreactive (3.6%)--unorganized granuloma with macrophages, lymphocytes, plasma cells and polymorphs with non caseating necrosis. Though the number of bacilli in the sections differed in each group, there were no differences in culture positivity, Mantoux reaction or the clinical features. It is likely that the spectrum of histological responses seen in tuberculous lymphadenitis is the end result of different pathogenic mechanisms underlying the disease.
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Adolescente , Adulto , Idoso , Biópsia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Linfonodos/microbiologia , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis , Tuberculose dos Linfonodos/microbiologiaRESUMO
To understand whether the presence of cold reactive lymphocytotoxic antibodies (LCA) (reactive at 15 degrees C) in the system has any effect on immunity to tuberculosis lymphocytotoxic antibodies to adherent cells (enriched-B cells) and non-adherent cells were studied in active-TB (n = 42) and inactive-TB (cured) patients (n = 49) and healthy controls (n = 32). The plasma samples of inactive-TB patients showed higher percentage of positivity for lymphocytotoxic antibodies (36.7%) than the active-TB patients (21.4%) and control subjects (18.8%). No significant difference on antibody and lymphocyte response against Mycobacterium tuberculosis culture filtrate antigens was observed between LCA positive and LCA negative active-TB patients and normal healthy controls. Further, determination of HLA-DR phenotype of the patients and control subjects showed that individuals positive for lymphocytotoxic antibodies were more among HLA-DR2 positive and DR7 positive active-TB patients and control subjects than non-DR2 and non-DR7 subjects. The present study suggests that the cold reactive lymphocytotoxic antibodies may be against B-lymphocytes and persistent for a longer time. HLA-DR2 and -DR7 may be associated with the occurrence of LCA activity. Further, the presence of LCA has no immunoregulatory role on immunity to tuberculosis.
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Adulto , Soro Antilinfocitário/sangue , Feminino , Antígenos HLA-DR/análise , Humanos , Masculino , Pessoa de Meia-Idade , Tuberculose Pulmonar/imunologiaRESUMO
Association of HLA-DR2 genes/gene products has been shown with pulmonary tuberculosis (PTB) patients in India. In the present study, the influence of HLA-DR2 and non-DR2 genes/gene products on immunity to tuberculosis has been studied. Plasma samples of -DR2 positive patients (active and inactive TB) showed a higher antibody titre to Mycobacterium tuberculosis culture filtrate antigens than non-DR2 (-DR2 negative) patients. Immunoblot analysis revealed a trend towards an increased percentage of DR2 positive patients recognizing 38, 32/34 and 30/31 kDa antigens of M. tuberculosis than DR2 negative patients. A low spontaneous lymphoproliferative response (without antigen stimulation) was seen in HLA-DR2 positive active TB patients than HLA-DR2 negative patients. However, the antigen stimulated lymphocyte response was higher in the -DR2 positive patients (active and inactive TB) when compared to non-DR2 patients. Further, an inversional correlation between antibody titre and spontaneous as well as antigen induced lymphocyte response (measured by 3H thymidine uptake and expressed as counts per minute) was seen in HLA-DR2 positive active PTB patients than non-DR2 patients. The present study suggests that HLA-DR2 genes/gene products may be associated with a regulatory role in the mechanism of disease susceptibility to tuberculosis. The genes while augmenting the humoral immune response, they suppress the spontaneous and antigen induced lymphocyte response in -DR2 positive patients with active disease.
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Adulto , Formação de Anticorpos/genética , Antígenos de Bactérias/imunologia , Células Cultivadas , Feminino , Antígeno HLA-DR2/genética , Humanos , Linfócitos/imunologia , Masculino , Infecções por Mycobacterium não Tuberculosas/genética , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/genéticaRESUMO
HLA-A, -B, -DR and -DQ antigen profile was studied in pulmonary tuberculosis patients (n = 209) and their spouses (family contacts; n = 50) and healthy volunteers (n = 72). An increased frequency of HLA-A-10, B7, B15, DR2 and DQ1 was seen in the pulmonary-TB (PTB) patients when compared to the total control subjects (n = 122). However, a significant increase was seen only with HLA-DR2 (P < 0.001; Pc < 0.01; Relative Risk 2.3) and -DQ1 (P < 0.005; Pc < 0.015; Relative Risk 2.8). Among the spouses and the corresponding patients, a similar increase of HLA-DR2 was seen. A decreased frequency of HLA-A19, B8, B17, B35, DR5 and DR6 were seen in PTB as compared to control groups. The present study suggested that HLA-DR2 and DQ1 genes/gene products may be associated with the susceptibility to tuberculosis either alone or in combination with other HLA or non-HLA genes.
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Adulto , Feminino , Antígenos HLA/análise , Antígenos HLA-DQ/análise , Antígeno HLA-DR2/análise , Humanos , Masculino , Cônjuges , Tuberculose Pulmonar/imunologiaRESUMO
Twenty three clinical isolates M. tuberculosis and the reference strain, M. tuberculosis H37Rv were tested for their susceptibility to trifluoperazine (TFP) by the standard broth dilution method and the bioluminescence assay. The results showed that in 15 of the 23 isolates, the minimal inhibitory concentration (MIC) was identical in both the methods and in the remaining 8 isolates the difference in the MIC values between the methods, was less than two fold and was not significant. The findings suggest that the measurement of adenosine triphosphate (ATP) by bioluminescence assay can be employed as an alternative method for the rapid screening of clinical isolates for their susceptibility to anti-mycobacterial agents.
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Trifosfato de Adenosina/metabolismo , Medições Luminescentes , Testes de Sensibilidade Microbiana/métodos , Mycobacterium tuberculosis/efeitos dos fármacos , Trifluoperazina/farmacologiaRESUMO
Intraspecies differentiation was studied on 68 M. tuberculosis strains obtained from 6 states of India by restriction fragment length polymorphism (RFLP) using a direct repeat probe (DR probe) hybridised with Alu I digest of DNA. Most strains showed polymorphism based patterns that comprised between 2 to 7 bands and were grouped into 26 RFLP types. Of the 11 strains tested from Amritsar, 8 were RFLP type 5; the remaining 3 were of type 11 and were exclusively confined to this region. The strains from other regions were more heterogeneous. We confirm that DR-associated RFLP can be an excellent tool for the differentiation of M. tuberculosis strains. Depending on their geographical origin, these strains can be differentiated to a large extent by DR fingerprinting.
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Impressões Digitais de DNA , DNA Bacteriano/análise , Mycobacterium tuberculosis/genética , Polimorfismo de Fragmento de Restrição , Sequências Repetitivas de Ácido NucleicoRESUMO
A total of 139 guineapigs were used to study the immune response and its modulation induced by Mycobacterium avium complex (MAC) and M. fortuitum complex strains obtained from different sources in the south Indian BCG trial area. The guineapigs were divided into groups and some were directly sensitised/immunised with different MAC strains. M. fortuitum complex strain or BCG and others were sensitised with MAC or M. fortuitum complex and then immunised with BCG. The resulting delayed type hypersensitivity (DTH) response in the different groups of guineapigs was studied by skin tests using PPD-RT23 and PPD-B, and protective response was studied by challenging the guineapigs with a south Indian low virulent strain of M. tuberculosis and enumerating the bacilli in spleen at different points of time. The 3 strains of MAC induced similar low levels of DTH to PPD-RT23 but much higher and varying levels of DTH to PPD-B. MAC strains from soil and sputum induced different levels of immune modulation during subsequent immunisation with BCG on the DTH response to PPD-RT23 and PPD-B. At 2 wk after challenge, 23.8, 81 and 90.5 per cent protection was induced by the standard strain, soil isolate and sputum isolate of MAC, respectively, while 33.3 per cent protection was induced by the M. fortuitum complex strain compared to the protection induced by BCG alone. Prior exposure to MAC or M. fortuitum complex did not have any modulatory effect on the protective immunity due to BCG at this time point. However, at 6 wk after challenge, while the guineapigs immunised with BCG were protected, modulation of the protective response resulting from BCG was observed in the guineapigs sensitised with MAC and M. fortuitum from soil.
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Animais , Vacina BCG/administração & dosagem , Cobaias , Humanos , Hipersensibilidade Tardia , Índia , Micobactérias não Tuberculosas/imunologia , Infecções por Mycobacterium não Tuberculosas/imunologia , Complexo Mycobacterium avium/imunologia , Infecção por Mycobacterium avium-intracellulare/imunologia , Testes Cutâneos , VacinaçãoRESUMO
Epidemiological picture of tuberculosis in India is complex with wide variation in the annual risk of infection and prevalence of disease. The concentration of the disease among younger age groups makes tuberculosis a major socio-economic burden in India. The disability adjusted life years (DALYS) is estimated to be around 63 and 46 lakhs of years of life lost in men and women respectively. The burden is likely to increase with HIV epidemic with an increase of cases with dual infection, increase in morbidity and mortality due to tuberculosis. Management of drug resistant tuberculosis is a major hurdle in tuberculosis control and is a major step in cutting the chain of transmission to those with HIV infection, AIDS and immunodeficiency. Development of new therapeutic modalities to address this problem are also urgently required. Poor patient compliance has been the reason for failure of many control programmes. Operational research studies conducted by the TRC have resulted in elucidation of socio-behavioural aspects of patients which need further investigation for remedial measures. Studies to improve drug delivery and to measure the impact of health education and mass media on compliance are areas which need to be concentrated. Newer techniques such as DNA fingerprinting need to employed to improve knowledge of the patterns of transmission in communities. The impact of HIV infection on tuberculosis and the role of chemoprophylaxis in HIV infected individuals in high risk populations, children in close contact with newly diagnosed patients and HIV infected individuals need to be urgently explored. Improved methods for diagnosis of Mycobacterium tuberculosis infection must await considerable advance in the understanding of basic immunology, mycobacterial antigenic structure and host-parasitic interaction.
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Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Índia/epidemiologia , Lactente , Recém-Nascido , Masculino , Pesquisa , Tuberculose/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológicoRESUMO
Gastric lavage (GL) was collected for culture of tubercle bacilli from children too young to expectorate sputum. The selective Kirchner's liquid medium (SKLM), routinely used as one of the media for culture of all extrapulmonary specimens, was found to often get contaminated when cultured with GL. We have shown that vancomycin at a concentration of 10 mg/l successfully reduced the contamination from about 60 to 20 per cent, and enhanced the isolation rate of tubercle bacilli from 3 to 6 per cent. Decontamination of the liquid culture before subculture on solid medium also helped to reduce the contamination rate. Vancomycin was found to be an effective selective drug for use in the Kirchner's liquid medium for culture of tubercle bacilli.
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Técnicas Bacteriológicas , Pré-Escolar , Meios de Cultura , Lavagem Gástrica , Humanos , Micobactérias não Tuberculosas/efeitos dos fármacos , Vancomicina/farmacologiaRESUMO
A total of 125 sputum specimens, collected in the field, were homogenised, aliquoted in sterile universal containers and randomly allocated to the cetylpyridinium chloride - sodium chloride (CPC-NaCl) method and sodium hydroxide (NaOH) method for culture of tubercle bacilli. After storage for 8 days at ambient temperature in the field laboratory at Thiruvallur, the aliquots were transported to the main laboratory at Madras where they were processed for culture by the respective methods. The yield of positive cultures in the CPC-NaCl (31/125) method was only marginally better than that in the NaOH method (27/125) (95% CI being-3.4 to 9.8%), while the contamination of cultures was significantly less in the CPC-NaCl method (3/125) than in the NaOH method (12/125) (95% CI being 2.2 to 12.2%). As the CPC-NaCl method has advantages over the NaOH method in reducing contamination, in augmenting the yield of positive cultures and also in its simplicity, it can be applied in field studies.
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Técnicas Bacteriológicas , Cetilpiridínio , Humanos , Micobactérias não Tuberculosas/isolamento & purificação , Cloreto de Sódio , Hidróxido de Sódio , Manejo de Espécimes/métodos , Escarro/microbiologiaRESUMO
A direct sensitivity test for rifampicin has been standardised for early detection of resistance for the mycobacterium tuberculosis smear positive sputum samples. Indirect sensitivity tests set up from primary cultures of the same samples served as controls. The direct test showed 95 per cent agreement with the standard indirect test and as such 74 per cent and 90 per cent of the resistant strains were detected by the fourth week and fifth week, respectively, with an overall gain of 4-5 wks time. Resistance could be detected earlier for multibacillary specimens. This direct sensitivity test on Lowenstein Jensen (LJ) medium offers a feasible alternative for laboratories which lack facilities to perform drug susceptibility tests by the rapid but sophisticated and costly BACTEC method. The method is simple to perform, economic, reliable and amenable to confirmation by the indirect test, if needed.