trans-4,4'-Dihydroxystilbene (DHS) protects PC12 cells from oxidative damage but induces reactive oxygen species-mediated apoptosis in SHSY-5Y cell line.

Polyphenols can exert both, antioxidant and pro-oxidant properties, depending on cell types as well as their concentrations. Hence, it was of interest to examine if the naturally occurring resveratrol analog, trans-4,4'-dihydroxystilbene (DHS) also exert both these activities in a biphasic or cell-specific manner. In this study, we established the cytoprotective action of DHS against hydrogen peroxide (H2O2)-induced apoptotic death of the PC12 cells. DHS reduced mitochondrial membrane permeabilization and deactivated reactive oxygen species (ROS)-mediated caspase-3 activation in the H2O2-treated PC12 cells. However, it induced apoptosis in the human neuroblastoma SHSY-5Y cell line by destabilizing mitochondrial membrane, augmenting ROS and activating caspapse-3. DHS showed better activity than resveratrol in both the chosen models.

Epidemiological trends of leprosy elimination in CLTRI rural field operation area, Tamil Nadu, India.

The analysis of computerized data of patients in our Rural Field Operation Area (Kunrathur Taluk, Kancheepuram District, Tamil Nadu) from the start of MDT in 1986 has shown a decrease of leprosy prevalence from 275/10000 in 1986 to 0.7/10000 in 2005. Leprosy has been eliminated as a public health problem after 19 years of MDT implementation. Although the control programme was started in 1962, MDT implementation began only in 1986. The new case-detection rate has declined significantly from 27.3 in 1987 to 2.4/10000 in 2005 (y = -1.6x + 2325.1, p = < 0.05). The age-specific cumulative detection rates calculated showed highest case-detection at 10-14 years for total, 10-14 years for PB, 50-54 for MB, and 10-14 for both males and females. MB percentage was more among new cases in the last three years as compared to the initial three years, and this difference was found to be statistically significant, but there was no significant difference between the first three and the last three-year periods in child, male and disability rates (grade +/-2) among new cases. Thus, the declining trend in NCDR has not reflected any change in sex and age-groups of new cases. This analysis strengthens the hypothesis of sub-clinical cases possibly transmitting the disease and MB cases accruing after long incubation period.

A study on trend of relapse in leprosy and factors influencing relapse.

A retrospective analysis of data pertaining to the rural field operation area of the Central Leprosy Teaching and Research Institute, Chengalpattu, Tamil Nadu, was carried out to determine the magnitude of relapse after MDT and its significance with other variables. The study included 3248 leprosy patients who have successfully completed treatment during 1987-2003, of whom 2892 were PB and 356 MB cases. A total of 58 cases of relapse was reported which gives a crude cumulative relapse rate of 1.78% for the 16-year period of follow-up and the rates for PB and MB were 1.9% and 0.84% respectively. With respect to PB cases, 68% of relapses were reported in the first 3 years of RFT. The person-year relapse rate was highly significant with regard to the number of skin lesions (p<0.0002) and nerve involvement (p<0.0002). The person-year relapse rate did not differ significantly between PB and MB leprosy, male and female, and child and adult cases. RFT year cohort relapse rate reveals that the introduction of MB-MDT regimen for PB leprosy had resulted in the reduction of relapses among PB cases after 1998. The relapse rate with reference to the time gap after RFT reveals that relapse declines with passage of time after RFT. The risk of relapse was very low in both PB and MB leprosy which fact emphasizes that proper counselling about signs and symptoms of relapse during RFT is adequate to combat the problem. A majority of relapses occurred in the first three years after RFT. The number of skin lesions and involvement of nerves were the main risk factors for relapse.

Leprosy situation in endemic states of India and prospects of elimination of the disease.

In India there is a dramatic fall in the prevalence rate (PR) of leprosy, but the new case-detection rate (NCDR) has not been reduced concomitantly. It is the operational efficiency of the National Leprosy Eradication Programme (NLEP) that has led to a significant reduction in the NCDR in Andhra Pradesh and Tamil Nadu. The ratio of PR to NCDR has been declining in these two states and it reveals that elimination could be reached even with the high NCDR level of 3 to 4 per 10000 population, particularly if single skin lesion (SSL) cases are discharged through single dose treatment of rifampicin, ofloxacin and minocycline (ROM). On the other hand, the significant number of cases detected in Bihar and Orissa during modified leprosy elimination campaigns (MLECs) reveals that there are lacunae in operational activities in new case-detection resulting in a large number of undetected cases in the community. Only one-third of the cases are reporting voluntarily. Awareness of leprosy is not adequate to motivate the patients to report voluntarily and complete their treatment, thus underscoring the need for relying on active case-detection so that transmission can be broken and elimination of leprosy achieved. In addition, the influence of socio-economic factors on continued occurrence of leprosy cannot be ruled out. The establishment of a sentinel surveillance system along with a computerized simplified information system to gain in-depth knowledge on the functioning of the NLEP will ensure operational efficiency. In view of this situation, the NLEP should adopt a more realistic approach towards reaching the elimination goal.

Data utilization and analytical skills among NLEP managers. National Leprosy Elimination Programme.

Mid-level managers of the National Leprosy Elimination Programme, India were assessed regarding their ability to turn routine data received from primary units into tools for management, analysis and decision making. Sixty-two managers (25 District leprosy officers, 37 Medical officers) were administered a questionnaire containing 20 questions on calculations of rates, ratios, proportions, percentages as well as construction and interpretation of graphs. It was found that 11% of the study subjects scored very poor, 48% scored poor, 35% scored good and only 5% of the managers scored very good. Among the district leprosy officers, 8%, 40%, 48% and 4% were rated as performing very poor, poor, good and very good, respectively. Among the medical officers, the corresponding figures were 14%, 54%, 27% and 5%.

Multiple drug resistant non typhoidal Salmonella spp associated with acute diarrheal disease.

Rectal swabs/stool specimens from 115 children (0-5 years) suffering with acute diarrhea were screened for non typhoidal salmonella species. 7 (6%) patients were found to be positive for non typhoidal salmonella. 4 (3.47%) were positive for S. paratyphi B and 3 (2.6%) were positive for S. typhimurium. Multidrug resistance was seen in 57 percent of the strains. All strains were sensitive to Ciprofloxacin. All strains were resistant to Ampicillin followed by Ciprofloxacin. All strains were resistant to Ampicillin followed by Gentamycin (43%), Kanamycin (43%), Tetracycline (43%), Streptomycin (28.5%) and Chloramphenicol (28.5%).

Prospects for elimination of leprosy in India by 2000 AD.

Data regarding the trends of new-case detection rates of leprosy for India as a whole, for the State of Andhra Pradesh, and for Srikakulam district in Andhra Pradesh were generated and projected up to 2000 AD. The prevalence rate by 2000 AD was worked out based on these new -case detection rates. The projections show that at the current slowly declining trend of new-case detection, with 20% MB cases among the newly detected cases and the current mean duration of treatment, the elimination goal of leprosy by 2000 AD, could possibly be achieved at Srikakulam district level only, where the MDT project has been under implementation for over ten years, but not at the State or country levels. The achievement of elimination goal should be possible in other geographic units also if the duration of disease could be shortened to one month or less, for both paucibacillary and multibacillary types of leprosy.

Deformity incidence in leprosy patients treated with multidrug therapy.

The records of 2,285 (2,007 paucibacillary (PB) and 278 multibacillary (MB)) cases of leprosy which were declared as released from treatment (RFT) after multidrug therapy (MDT) and under surveillance as per the National Leprosy Eradication Programme (NLEP) guidelines in the rural field practice area of Central Leprosy Teaching & Research Institute (CLTRI), Chengalpattu, between September 1986 and September 1993 were analyzed for collecting data on the incidence of deformity. Of the 2,285 cases 2,053 (1,947 PB and 106 MB) did not have deformity at the commencement of treatment. Three MB cases and one PB case out of the 2,053 developed deformity (all grade II) during the course of treatment. No patient developed deformity during surveillance. Thus the deformity incidence in the population of patients was 0.681 per 1000 person-years of observation. Age, sex, type of disease, prior dapsone monotherapy and nerve involvement at the commencement of treatment appear to influence the deformity incidence. The risk of development of deformity in patients treated with MDT appear to be very low and analysis of larger data sets is suggested to corroborate the above findings as the information would be useful for planning prevention and management of deformity services.

Mycobacterium leprae soluble antigen (Rees) skin test responses in an endemic population in India.

The response to intradermal administration of Rees soluble skin test antigen was studied in 12,142 randomly selected individuals living in a highly endemic area in South India. Taking a cut-off point of 12 mm induration as the criterion for 'positivity', 73% of PB cases, 45% of MB cases and 63% of noncase population (67% in contacts and 63% in non-contacts) were found to be positive. Age-specific positivity rates were higher in males than in females and in adults than in children. The difference in age-adjusted positivity rates between cases, contacts an noncontacts in the female population was found to be significant. However, the differences in reaction response are not sufficient to identify the sub-populations of cases, contacts and noncontacts and as such this antigen is not likely to be useful in epidemiological studies of infection and evolution of clinical disease in high endemic populations.

Time lag between case registration and commencement of treatment in a leprosy control unit.

Analysis of client-based data as a part of computerised management information system in a Government leprosy control unit in Tamil Nadu reveals that there was delay in initiating treatment of leprosy patients. The mean and standard deviation of the period of delay for cases registered before, within 6 months and after 6 months of start of MDT in the Unit were 6.80 +/- 6.40, 1.97 +/- 3.60 and 0.90 +/- 2.21 months respectively. Further, the delay was longer in PB, female and child cases. Giving priority to therapy for backlog cases and an effective monitoring system with specific indicator for time lag in starting treatment is indicated.

Plasminogen activator: Isolation and purification from lymphosarcoma of ascites bearing mice.

Plasminogen activator secreted by lymphosarcoma (ascites) of mice was purified up to 163-fold by ammonium sulphate fractionation at 35% saturation and chromatography on p-aminobenzamidine-Sepharose 4B. The purified activator contained specific activity of 9980 IU/mg. The plasminogen activator displayed homogeneity by polyacrylamide slab gel electrophoresis and high performance liquid chromatography. The activator consisted of a single polypeptide chain with an apparent molecular weight of 66,000 daltons as determined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis under reducing conditions as well as gel filtration on Sephadex G-100. Distinct differences between this activator and urokinase were discernible in respect of specific activities, fibrin affinity and immunochemical properties. The lymphosarcoma activator appears to be of tissue-type origin since it showed gross similarity to standard tissue plasminogen activator in terms of modes of binding to fibrin and immunological attributes.

A computerized information system for evaluation of NLEP through monthly progress reports.

A computerized system for monitoring district-wise operational performance and epidemiological progress using existing regular and special monthly reports of the National Leprosy Eradication Programme (NLEP) is presented. The same system, with some minor modifications could be used for programme assessment at the Leprosy Control Unit level also. The advantage of the system is the speed with which it can generate output in the form of comparative tables and graphs for different regions for use by programme managers for making overall assessments in time and for sending feedback reports to workers at various levels, for self-assessment and for taking timely corrective action. The system presented provides immediate and easy access to the stored and/or processed information (indicators etc.,) at any time. The system has been pilot-tested using monthly reports from eighteen districts of Tamil Nadu.

Interaction of proteins with detergents: Binding of cationic detergents with lysozyme.

Binding studies of cationic detergents such as cetyl trimethylammonium bromide, Cetylpyridinium bromide and dodecyl trimethylammonium bromide with lysozyme were carried out by equilibrium dialysis, ultraviolet difference and circular dichroism techniques at 25 C. Binding isotherms at pH 5·0, 7·0 and 9·0 show cooperative binding at all concentrations of detergents and the number of available binding sites in lysozyme increases with pH. Gibbs free energy of binding calculated on the basis of Wymans’ binding potential concept increases with pH indicating increased binding strength at higher pH. The ultraviolet difference spectra of the detergent complexes with lysozyme at pH 7·0 and 9·0 in the region of 250-300 nm indicate the involvement of aromatic amino acid residues as probable binding sites and also the carboxylate groups since the binding is cooperative. The circular dichroism spectra also indicate the involvement of aromatic amino acid residues in the binding of these detergents. This is substantiated by the decrease in the intensity of the aromatic positive bands in the near ultraviolet region. The increase in the magnitude of [θ ]222 nm values in the far ultraviolet region with the increase in the concentration of the detergent in the complex indicates conformational changes resulting in an increase of α-helical content producing a more ordered structure of lysozyme. These binding studies show that at pH 7·0 and 9·0, hydrophobic interactions play a major role, while at pH 5·0 only electrostatic interactions play prominent role in the binding of these detergents.

Interaction of lysozyme with antibiotics –binding of penicillins to lysozyme.

Binding of lysozyme with the antibiotics such as penicillin-G, penicillin-V and methicillin at different concentrations and pH was studied by equilibrium dialysis. Co-operative binding isotherms were observed at pH 5.0,7.0 and 9.0 with all the penicillins and the binding ratios decreased slightly with the increase of pH. The Gibbs free energy change calculated on the basis of Wyman's binding potential concept decreased slightly with the increase of pH indicating slight decrease in the binding strength at higher pH in the case of all penicillins. The ultra-violet difference spectra of lysozyme-penicillin complexes showed a less intense peak in the region of 284-300 nm at pH 5.0. Only penicillin-G complex had a peak at pH 7.0 at these wavelengths with less intensity compared to that at pH 5.0. However, none of the penicillins showed discrete peaks in this region at pH 9.0. The appearance of peaks in the difference spectra of all these complexes at pH 5.0 and with only penicllin-G complex at pH 7.0 in the aromatic region indicated hydrophobic interactions with tryptophan residues as the binding sites. In addition, the ionic interactions with lysine residues in lysozyme were also occurring. The conformational changes induced by the binding of penicillins to lysozyme monitored by circular dichroism showed a slight decrease in the aromatic bands in the 320- 250 nm region. However, in the 250-200 nm region, [θ]222nm values obtained at various concentrations of penicillins in the complex indicated an increased α- helical content generating a more ordered structure. These results led to the conclusion that both the hydrophobic and electrostatic interactions prevail in the binding of penicillins to lysozyme.