Observation of narrow fluorescence from doubly driven four-level atoms at room temperature

Unusually narrow fluorescence peaks are seen from Rubidium-85 atoms under the action of two driving laser fields that are in a three dimensional molasses configuration. One of the lasers is held at a fixed detuning from the "cooling" transition, while the other is scanned across the "repumping" transitions. The fluorescence peaks are split into symmetric pairs, with the seperation within a pair increasing with the detuning of the cooling laser. For large detunings additional small peaks are seen. A simple model is proposed to explain these experimental observations.Comment: 8 pages, 4 figures, needs epl.cl

Protocol for quantum-logical operations in an optical lattice using nonresonant absorption of photon pairs

Two nonidentical atoms may be entangled by inducing simultaneous cooperative absorption of a photon pair from a light field that is nonresonant to either atom in isolation. The atoms may be of two different elements, of different isotopes of the same element, or of a single isotope undergoing different transitions. Utilizing this cooperative process, we propose a protocol for a conditional operation with neutral atoms in an optical lattice. Current practical capabilities permit execution of the scheme

Simple spectrofluorimetric and microbiological assay methods for the estimation of ofloxacin in biological fluids

Objective: To evolve simple methods for the assay of ofloxacin in biological fluids. Methods: Simple methods for the estimation of ofloxacin in plasma, saliva and urine employing microbiological assay using plate diffusion technique and by fluorimetric method based on the measurement of native fluorescence emitted by ofloxacin, have been described. Results: The recovery of ofloxacin from all the three biologial fluids was 93-98% and the sensitivity was 0.5 μg/ml on all 5 different occasions by both the methods. Anti-TB drugs viz., rifampicin, ethambutol, isoniazid and pyrazinamide and also anti-leprosy drugs viz., dapsone and clofazimine at concentrations of 10 and 20 μg/ml did not interfere with the estimation of ofloxacin by either method. Ofloxacin is stable in biological fluids for a period of at least 8 days at -20°C. Conclusion: Both the methods described are simple, involve very few steps and do not need either costly chemicals or sophisticated equipments

Surveillance of drug-resistant tuberculosis in the state of Gujarat, India

BACKGROUND: Limited information about the prevalence of drug-resistant tuberculosis (TB) has been reported from India, the country with the world’s highest burden of TB. We conducted a representative state-wide survey in the state of Gujarat (2005 population: 56 million). METHODS: Mycobacterium tuberculosis isolates from a representative sample of new and previously treated smear-positive pulmonary TB (PTB) cases were subjected to drug susceptibility testing (DST) against fi rst-line drugs at a World Health Organization supranational reference laboratory. Isolates found to have at least both isoniazid (INH) and rifampicin (RMP) resistance (i.e., multidrugresistant TB [MDR-TB]) were subjected to second-line DST. RESULTS: Of 1571 isolates from new patients, 1236 (78.7%) were susceptible to all fi rst-line drugs, 173 (11%) had any INH resistance and MDR-TB was found in 37 (2.4%, 95%CI 1.6–3.1). Of 1047 isolates from previously treated patients, 564 (54%) were susceptible to all fi rst-line drugs, 387 (37%) had any INH resistance and MDR-TB was found in 182 (17.4%, 95%CI 15.0–19.7%). Among 216 MDR-TB isolates, 52 (24%) were ofl oxacin (OFX) resistant; seven cases of extensively drug-resistant TB (XDR-TB) were found, all of whom were previously treated cases. CONCLUSION: MDR-TB prevalence remains low among new TB patients in Gujarat, but is more common among previously treated patients. Among MDR-TB isolates, the alarmingly high prevalence of OFX resistance may threaten the success of the expanding efforts to treat and control MDR-TB

Evaluation of an Intermittent Six-month Regimen in New Pulmonary Tuberculosis Patients with Diabetes Mellitus

Background: The treatment of tuberculosis (TB) with category I regimen of the Revised National Tuberculosis Control Programme (RNTCP) for patients with diabetes mellitus (DM) needs evaluation. Objective: To assess the cure and relapse rates in 3 years, among the new smear-positive TB patients with Type-2 DM (DMTB) treated with CAT-I regimen (2E3H3R3Z3/4R3H3) of RNTCP. Methodology: TB suspects attending the diabetology units and the TB research centre (TRC) Chennai, were investigated. Eligible DMTB cases were enrolled. Baseline estimation of cardiac, renal, liver function tests and glycosylated-HBA1c were undertaken. All patients received 2E3H3R3Z3/4R3H3 under supervision at TRC. Clinical and sputum (smear and culture) examinations and monitoring of diabetic status were undertaken every month up to 24 months, then once in 3 months up to 36 months. Results: Of 100 patients admitted, 7 were excluded for various reasons from analysis. Of 93 patients, 87 (94%) had a favourable response at the end of treatment. Pre and post treatment mean glycosylated-HBA1c were 9.7% and 8.4 %.(>7% poor control). During follow-up period, 6 died and one lost to follow-up. Of the remaining, four relapsed. Conclusion: Category-I regimen, recommended for all the new smear-positive patients in the Indian TB programme, is effective in the treatment of DMTB patients, despite poor control of diabetes

Patoanatomski i imunohistokemijski nalaz neizdiferenciranog karcinoma sitaste kosti u domaće svinje - prikaz slučaja.

An undifferentiated ethmoid carcinoma with uncommon initial stage invasion into the brain parenchyma in an indigenous pig is reported. A nodular, fleshy tumor mass, located in the posterior part of the nasal sinus adjacent to the cribriform plate and pressing on the brain, was noticed on post mortem. Rarifaction of the cribriform plate was evident. The histological picture showed sheets of cells with nuclear atypia, anaplasia and hyperchromatic nuclei infiltrating into the brain parenchyma. Upon detailed examination, the neoplasm revealed a mixture of spindle, squamous and round tumor cells. The case was diagnosed as ethmoid carcinoma of undifferentiated type, as the epithelial origin of the neoplasm was proved by immunohistochemical positivity against an anti-pancytokeratin antibody.Opisan je karcinom sitaste kosti u domaće svinje s rijetko viđenim početnim stupnjem širenja na parenhim mozga. Čvorasta, mesnata tumorska masa bila je smještena na stražnjoj strani nosnog sinusa tik uz sitastu ploču i pritiskala je na mozak. Uočena je prorijeđenost sitaste ploče. Histološki je ustanovljena infiltracija moždanog parenhima sa stanicama s atipičnim, hiperkromatskim jezgrama i anaplazijom. Detaljnom pretragom dokazano je da se novotvorina sastojala od mješavine vretenastih, ljuskavih i kuglastih tumorskih stanica. Tumor je bio dijagnosticiran kao karcinom sitaste kosti neizdiferenciranog tipa s obzirom na to da je njegovo epitelno podrijetlo bilo dokazano imunohistokemijskim postupkom upotrebom antipancitokeratinskog protutijela

Sensitivity & specificity of combination testing algorithms for HIV in a tuberculosis clinic

Introduction: Co-management of tuberculosis (TB) and HIV is complicated by pharmacologic drug interactions between rifampicin (RMP) and certain classes of antiretroviral agents. The NNRTIs Nevirapine (NVP) or Efavirenz (EFV), used to HIV infection, are known to induce the CYP 450 enzyme system. Thus when RMP is co-administered along with NVP or EFV, the bioavailability of RMP could be lowered leading to drug resistance and treatment failure. Objectives: To study the steady state pharmacokinetics of RMP in HIV and HIV-TB patients receiving antiretroviral regimens containing NVP or EFV respectively. Methods: The study population comprised of HIV and HIV-TB patients undergoing antiretroviral treatment with NVP and EFV containing regimens respectively. These patients were also receiving concomitant RMP. Rifampicin was estimated by HPLC in blood collected at different time points after drug administration. The pharmacokinetic variables of RMP were calculated using WinNonlin software. Results & Conclusions: Co-administration of NVP or EFV did not alter the pharmacokinetics of RMP in HIV and HIV-TB patients, suggesting that the dose of RMP need not be altered during antiretroviral treatment with NVP or EFV

Sputum conversion at the end of intensive phase of Category-1 regimen in the treatment of pulmonary tuberculosis patients with diabetes mellitus or HIV infection: An analysis of risk factors

Background & objectives: New smear-positive pulmonary tuberculosis (PTB) patients in the Revised National Tuberculosis Control Programme (RNTCP) are treated with a 6-month short-course chemotherapy (SCC) regimen irrespective of co-morbid conditions. We undertook this retrospective analysis to compare sputum conversion rates (smear, culture) at the end of intensive phase (IP) of Category-1 regimen among patients admitted to concurrent controlled clinical trials: pulmonary tuberculosis alone (PTB) or with type 2 diabetes mellitus (DM-TB) or HIV infection (HIV-TB), and to identify the risk factors influencing sputum conversion. Methods: In this retrospective analysis sputum conversion rates at the end of intensive phase (IP) in three concurrent studies undertaken among PTB, DM-TB and HIV-TB patients, during 1998 – 2002 at the Tuberculosis Research Centre (TRC), Chennai, were compared. Sputum smears were examined by fluorescent microscopy. HIV infected patients did not receive anti-retroviral treatment (ART). Patients with DM were treated with oral hypoglycaemic drugs or insulin (sc). Results: The study population included 98, 92 and 88 patients in the PTB, DM-TB and HIV-TB studies. At the end of IP the smear conversion (58, 61, and 62%) and culture conversion (86, 88 and 92%) rates were similar in the three groups respectively. The variables associated with lack of sputum smear or culture conversion were age >45 yr, higher pre-treatment smear and culture grading, and extent of the radiographic involvement. Interpretation & conclusions: Our findings confirm that the current policy of the control programme to treat all pulmonary TB patients with or with out co-morbid conditions with Category-I regimen appears to be appropriate

Management of Multi Drug Resistance Tuberculosis in the Field: Tuberculosis Research Centre Experience

Setting: Multi-drug TB resistant (resistant to isoniazid and rifampicin) patients identified from a rural and urban area. Objective: To study the feasibility of managing MDR TB patients under field conditions where DOTS programme has been implemented Methods: MDR TB Patients identified among patients treated under DOTS in the rural area and from cases referred by the NGO when MDR TB was suspected form the study population. Culture and drug susceptibility testing were done at Tuberculosis Research Centre (TRC). Treatment regimen was decided on individual basis. After a period of initial hospitalization, treatment was continued in the respective peripheral health facility or with the NGO after identifying a DOT provider in the field. Patients attended TRC at monthly intervals for clinical, sociological and bacteriological evaluations. Drugs for the month were pre-packed and handed over to the respective center. Results: A total of 66 MDR TB patients (46 from the rural and 20 from the NGO) started on treatment form the study population and among them 20 (30%) were resistant to one or more second line drugs (Eto, Ofx, Km) including a case of “XDR TB”. Less than half the patients stayed in the hospital for more than 10 days. The treatment was provided partially under supervision. Providing injection was identified to be a major problem. Response to treatment could be correctly predicted based on the 6-month smear results in 40 of 42 regular patients. Successful treatment outcome was observed only in 37% of cases with a high default of 24%. Adverse reactions necessitating modification of treatment was required only for three patients. Implications Despite having reliable DST and drug logistics, the main challenge was to maintain patients on such prolonged treatment by identifying a provider closer to the patient who can also give injection, have social skills and manage of minor adverse reactions