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M Natrajan

Publications and source records attributed to M Natrajan.

18 recordsLinked to original sources
PubMed2005

Diagnostic value of in situ Polymerase Chain Reaction in leprosy.

OBJECTIVE: This prospective study was carried out to assess the diagnostic value of in situ Polymerase Chain Reaction in leprosy, particularly in enhancing the histopathological diagnosis. METHOD: Clinical examination of 20 patients (< 16 yr) was done and skin smear for AFB was prepared. Biopsy of lesion site was taken for histopathological examination and in situ PCR testing. RESULTS: The histopathological examination confirmed the clinical diagnosis in 45% cases only; non-specific histopathology was reported in the remaining 55% cases. In situ PCR showed a positivity of 57.1% in early/localized form of leprosy (IIBT) and 61.5% in (BB/BL) group. When compared to histopathology examination, a significant enhancement of 15% in diagnosis was seen. With in situ PCR, the diagnosis could be confirmed in 4/11 (36.3%) cases with non-specific histopathological features, (which is common in early disease) in addition to confirmation of 8/9 (88.8%) histopathologically-confirmed tissue sections. Histopathology and in situ PCR, combined together, confirmed the diagnosis in 13/20 cases (65% of total cases). CONCLUSION: Thus, in situ PCR is an important diagnostic tool especially in early and doubtful cases of leprosy.

Adolescent↗
PubMed2005

Persister studies in leprosy patients after multi-drug treatment.

Cutaneous biopsies were collected from leprosy patients who attended the out-patient department of the Institute for treatment at different intervals, i.e., 12 months, 18 months, 24 months, 36 months, and more after beginning the multi-drug treatment therapy (M.D.T.). The patients belonged to the two drug regimens; (i) standard multibacillary (MB) M.D.T. after 12, 24, and 36 months; or (ii) standard M.D.T. + Minocycline 100 mg once a month (supervised) + Ofloxacin 400 mg once a month supervised for 12 months Biopsies were processed for mouse footpad inoculation and for estimating ATP levels by bioluminescence assay as per established methods. Viable bacilli were observed in 23.5% up to 1 year, 7.1% at 2 years, and in 3.84% at 3 years of M.D.T. by MFP and 29.4%, 10.7%, and 3.84% by ATP assay in the M.D.T. group at the same time period, respectively, but not in M.D.T. + Minocycline + Ofloxacin group after one year. The overall percentage of persisters was 5.55% by MFP and 7.14% by ATP assay up to 3 years of treatment.

Adenosine Triphosphate↗
PubMed1999

Detection of viable organisms in leprosy patients treated with multidrug therapy.

Cutaneous biopsies were collected from multibacillary leprosy patients who attended the out-patient department of Jalma Institute for treatment at different time intervals, i.e. 6 months, 12 months, 18 months, 24 months, 30 months, 36 months and 42 months after starting multidrug therapy (MDT) when they were still skin smear positive. Biopsies were processed for inoculation into mouse foot pad (MFP) and estimation of bacillary ATP levels by bioluminescent assay (ATP assay) by earlier established procedures. Viable bacilli were detectable after 1 year (25% cases by MFP and 31% cases by ATP assay), 2 years (8% cases by MFP and 12% cases by ATP assay) and 3 years (4% cases by both MFP and ATP assays). Overall, the percentage of the persisters was 10% by MFP and 13% by ATP assay. It would be important to carry out surveillance studies in larger number of BL/LL cases to know the trends and also the resultant relapses.

Adult↗
PubMed1999

Histology and immuno-histology of lesions clinically suspicious of leprosy.

Forty-six patients presenting with lesions clinically suspicious of leprosy were selected among patients attending the outpatient department (OPD) of our Institute. The lesions were biopsied deeply for histological analysis. The cases chosen commonly belonged to the 20-35 years age group, were predominantly males, with rare cases of leprosy within the family (2/46, 4.35%). The clinical presentation in most of the cases was that of a solitary lesion, (44/46, 95.65%) located in one of the extremities (40/46, 86.95%). A positive Mitsuda reaction could be elicited in 40% of the cases. Routine histopathologic analysis using defined criteriae, has established the diagnosis of leprosy in 16/46 (34.78%) cases with positivity for acid-fast bacilli in 4 cases. The remaining cases (25/46, 54.35%) exhibited a non-specific histopathology with a perivascular/periadnexal mononuclear cell infiltrate, few (5/46, 10.86%) exhibited minimal or no histopathological features. The sections with nonspecific or minimal pathology when immunostained for the presence of mycobacterial antigen exhibited positivity in 11/30 (36.6%) cases. Presuming the features observed to be consequent to the presence of antigens nearby, the diagnosis of leprosy was significantly enhanced compared to the diagnosis achieved with routine histopathology alone.

Adolescent↗
PubMed1999

Effect of treatment on PCR positivity in multibacillary leprosy patients treated with conventional and newer drugs ofloxacin and minocycline.

In order to develop objective criteria to monitor trends of therapeutic responses positivity of PCR signals and ATP assay methods has been compared in multibacillary (MB) leprosy patients. Biopsies from lesions of 95 BL/LL patients before and after one year of treatment with a new drug regimen comprising of conventional and newer drugs ofloxacin and minocycline have been studied. These biopsies were processed for bacillary ATP assay and PCR positivity for a 36 kDa gene target by earlier published methods. In the untreated patients bacillary ATP levels were detectable in all specimens and ranged from 0.02 to more than 36 pg/millions organisms. After one year of treatment ATP levels were not detectable in any of the 57 biopsies specimens available for analysis. However, PCR signals were detectable in 3 out of 57 biopsies. In two specimens signals were very weak detectable only by hybridization. It may be concluded that DNA based PCR assay may be useful in monitoring the trends of therapeutic responses in MB patients under treatment.

Adenosine Triphosphate↗
PubMed1997

Microdensitometric scanning procedure for quantitative assessment of hybridization of rRNA targeting probes in leprosy.

In order to develop an objective criteria of grading of positivity of hybridization signals of gene probes targeting rRNA, a microdensitometric scanning procedure was standardised. Ribosomal RNA was extracted from the bacilli harvested from biopsies of leprosy cases across the spectrum and blotted on nitro-cellulose membranes. M. leprae specific rRNA targeting oligonucleotide probes were end-labelled and hybridization was done by the technique standardised and published earlier. The autoradiographs were developed and microdensitometric scanning was done by altering different parameters. Positivity was graded in 5 grades and compared with visual positivity. Microdensitometric scanning procedure and 5 grade system appear to be useful and reproducible. Signals in paucibacillary specimens were in 2+ to 3+ grading range whereas those in multibacillary specimens varied in grades from 2+ to 5+. This approach appears to have potential usefulness for assessing the bacillary load (possibly viable) in the clinical specimens from leprosy cases.

Autoradiography↗
PubMed1996

Understanding anatomical terms.

Words are our masters and words are our slaves, all depending on how we use them. The whole of medical science owes its origin to Greco-Roman culture and is replete with terms whose high sound is not necessarily accompanied by sound meaning. This is even more the case in the initial, pre-clinical years. Anatomical terminology seems bewildering to the initiate; and maybe that is a reason why love of anatomy as a subject does not always spill over through later years. Employing certain classifications of the origin of the anatomical terms, we have prepared an anthology that we hope will ease the student's task and also heighten the student's appreciation of the new terms. This centers on revealing the Kiplingian "how, why, when, where, what, and who" of a given term. This presentation should empower students to independently formulate a wide network of correlations once they understand a particular term. The article thus hopes to stimulate students' analytic and synthetic faculties as well. A small effort can reap large rewards in terms of enjoyment of the study of anatomy and the related subjects of histology, embryology, and genetics. It is helpful to teachers and students alike. This exercise in semantics and etymology does not demand of the student or his teacher any background in linguistics, grammar, Greek, Latin, Sanskrit, anatomy, or medicine.

Anatomy↗
PubMed1996

Detection of M. leprae by gene amplification; combined ethidium-bromide staining and probe hybridization.

Biopsy and skin-scraping specimens from 130 leprosy cases across the disease spectrum (56 TT/BT/I, 73 BB/BL/LL, and 1 neuritic case) and 50 healthy contacts were studied to assess the application of gene amplification. The nucleic acids from these clinical specimens were extracted by an integrated freeze-thawing--optimized lysozyme-/proteinase-k treatment-purification and fractionation procedure. The nucleic acids from cultured organisms were isolated by the stepwise procedure earlier standardized at this laboratory. Gene amplification for a 360-bp fragment of the 18-kDa protein gene was carried out using primer and the procedure described by its developers, and a 360-bp fragment on Southern blot was taken as the yardstick of positivity. The polymerase chain reaction product was analyzed by electrophoresis, ethidium-bromide (EB) staining, and blot (B) hybridization. Overall sensitivity ranged from 71% in specimens with undetectable acid-fast organisms to 100% in specimens with demonstrable acid-fast bacilli. A positivity of 73% in TT/BT/I specimens and 93% in BB/BL/LL specimens was observed. Four combinations were discerned: EB+, B+ (71%); EB-suspicious, B+ (14%); EB-, B+ (3%) and EB-, B- (12%). By combining the blot hybridization with EB staining, the sensitivity could be significantly improved as compared to EB staining alone. The test was found to be absolutely specific by the absence of any false positivity in control specimens as well as with purified DNAs from mycobacterial as well as non-mycobacterial organisms, grown from these specimens. It is recommended that for optimum sensitivity and specificity both EB staining and blot hybridization should be done.

Biopsy↗
PubMed1995

Treatment of bacilliferous BL/LL cases with combined chemotherapy and immunotherapy.

Thirty-six, untreated borderline lepromatous/lepromatous (BL/LL) leprosy patients with an initial bacterial index (BI) of 4+ to 6+ were serially allocated to three treatment groups. Group I patients received a slightly modified WHO regimen (rifampin once a month, clofazimine and dapsone daily) and BCG intradermally (i.d.) (0.1 mg/per dose). Group II patients were administered the same MDT and Mycobacterium w (2 x 10(8)) killed bacilli/dose i.d., and Group III received the same MDT with 0.1 ml of distilled water i.d. Vaccination was repeated every 6 months. Biopsies were taken from the local site of vaccination and from a distant site, i.e., the back. The progress was monitored periodically by clinical, histopathological and bacterial (BI, mouse foot pad, ATP) parameters. Twenty-five patients had completed a follow up of more than 2 years. These included: 7 in Group I, 10 in Group II, and 8 in Group III. One patient of the MDT + BCG group who was progressing well dropped out after 28 months. In cases on combined chemotherapy and immunotherapy, no viable bacilli were demonstrable by mouse foot pad and ATP measurement after 6 months (at 12 months or afterward). However, in come of the control cases on MDT alone, viable bacilli could be detected even up to 18 months (by mouse foot pad) and 2 years (by ATP estimation). With 36 months of treatment, the mean BI decreased from 4.64+ to 1.66+ in the group on MDT alone (controls), 4.9+ to 0.08+ in the MDT + BCG group, and 4.75+ to 0 in the MDT+Mycobacterium w group. Compared with the MDT and MDT + BCG groups, the fall in the BI was significantly more in the MDT + Mycobacterium w group at 12, 18, and 24 months. While all of the cases in the Mycobacterium w groups became smear negative by 36 months, it took 42 months for all of the BCG group to achieve negativity. Immunotherapy appears to have a significant effect on the killing and clearance of bacilli and should be considered as an adjunct to chemotherapy, especially in bacilliferous lepromatous cases.

Adenosine Triphosphate↗
PubMed1995

Response of leprosy patients with single lesions to MDT.

This study reports the clinical profile and therapeutic response of seventy-two mono-lesions leprosy cases. These 72 cases were among 578 paucibacillary (PB) cases classified according to WHO (1982) and were followed-up on multidrug therapy (MDT). Of these 72 mono-lesion cases, 46 (64%) were tuberculoid (TT) cases, 24 (33%) were Indeterminate (Ind) cases and 2 (3%) were of borderline tuberculoid (BT) types. While 37.5% of these cases presented as macular patches, the remaining 62.5% had raised erythematous lesions. In majority of cases (94%), the lesions were present on the exposed parts like legs and feet, arms and hands, face, whereas only 6% presented on covered areas of trunk and buttocks. These cases were treated with dapsone 100 mg daily for 12 months and rifampicin 600 mg once a month for 6 months. After 6 months of MDT, lesions in 81% of the patients regressed clinically and by one year of therapy 96% of cases had regressed. Treatment was stopped in all cases by one year of therapy. There were no relapse or late reaction in the 5 years of post treatment follow-up. The response of mono-lesion PB cases was better than the multi-lesions PB cases at 6 months and during the post treatment follow-up period.

Adolescent↗
PubMed1995

Enhancement in the histological diagnosis of indeterminate leprosy by demonstration of mycobacterial antigens.

In a clinico-pathological study of Indeterminate leprosy, fifty-six cases were chosen based on specified clinical criteria. Their clinical features were noted, the smears for acid fast bacilli (AFB) were prepared from lesions, lepromin inoculation and biopsies were performed from the lesional edges. They were subsequently treated with a modified extended WHO regimen for paucibacillary leprosy. On routine hematoxylin eosin (HE) and Fite-Faraco staining of paraffin embedded sections, histopathological confirmation of Indeterminate leprosy was observed in only 17/56 (31%) of the clinically diagnosed cases whereas the remaining were labelled as non-specific pathology. Histometric analysis of all HE stained sections did not show any characteristic finding which could be considered as characteristic and discriminatory for Indeterminate leprosy. Immunoperoxidase staining for demonstration of mycobacterial antigen by direct staining procedure using conjugated rabbit anti-BCG and indirect three step procedure using primary rabbit anti-BCG and avidin biotin complex, was next performed on the sections exhibiting non-specific pathology. With the direct immunoperoxidase method, antigen was demonstrable in (11/35) 31% of the cases. The more sensitive indirect method could demonstrate the presence of antigen in (21/35) 60% of the cases. This study thus shows that demonstration of mycobacterial antigen by simple and inexpensive immunoperoxidase techniques enhances the histopathologic diagnosis of Indeterminate leprosy.

Adolescent↗
PubMed1990

The nature of bones and joints: a new perspective.

In human ontogeny recapitulating phylogeny, bones arrive late on the scene--long after neurogenesis, musculogenesis, organogenesis and so on are over--as islands of ossification in an ocean of collagen. This study confirms this developmental sequence by demonstrating, in cadavers, the rather independent nature of bone, to which nothing--muscle, tendon, ligament or articular cartilage--is attached. Bone is like the air in a tubeless tyre; it gives rigidity and shape to the tyre, and in return takes the shape of the tyre. The tibia, for example, is the bony tissue that is contained in tyre-like casing made of peritibial soft tissues whose inner limit is the periosteum, which continues proximally and distally as capsules of knee/ankle joint, and to which only are the articular cartilages of the knee and ankle attached, being clearly free from the bones. This study also exposes the truer nature of a joint wherein the articular cartilage assumes anatomic and physiologic significance hitherto unthought of.

Bone and Bones↗
PubMed1989

Immunotherapy of treated BL/LL cases with BCG: histopathological, immunohistological and bacteriological assessments.

The persistence of dead as well as viable bacteria is an important therapeutic problem in multibacillary leprosy. In highly bacillated patients, viable bacteria are detectable in 10-15% of cases after 2 years of treatment and none of these cases became smear negative by 2 years of recommended multidrug therapy (MTD). Immunotherapy trials using BCG (0.1 mg) by intradermal route have been undertaken in cases who had MDT for 2 years and who had viable bacilli by ATP photometry and/or FDA-EB staining. Biopsies and smears were taken from local as well as distant sites at 0.4 weeks and 6 months after BCG vaccination. Biopsies were processed for ATP counts, FDA-EB staining, histopathology and immunohistology for cell types at 0.4 weeks. There was transient effect on BI, ATP counts, FDA-EB staining at local as well as distant sites in some cases. Histopathology and immunohistological findings suggest that there is tendency to form epithelioid cell granuloma at local site in all cases and at distal sites in some. There was infiltration of subepidermal zone in one case, 4 weeks after vaccination. BCG may be of use as potential immunotherapeutic agent but its usefulness needs to be investigated in depth preferably in the beginning or early phases of chemotherapy and with also repeated inoculations.

BCG Vaccine↗
PubMed1989

Relapses in paucibacillary patients after treatment with three short-term regimens containing rifampin.

Three multidrug regimens all containing rifampin and dapsone have been tried for the treatment of 278 cases of paucibacillary leprosy. Regimen I was the one recommended by the WHO Study Group. Regimen II was the same as Regimen I with depsone alone continued for a further 6 months. Regimen III was the same as Regimen II but rifampin was given daily for the first 7 days. The patients were comparable with regard to disease classification, lepromin status, bacteriological status, and number of lesions. As reported earlier, the disease inactivity rates by 1 year of treatment were much greater with Regimens II and III than with Regimen I (94% and 97% vs 76%). Early reaction was seen in 6% of those in Regimen III and in none in Regimens I and II. Late reaction was observed in 9% of those in Regimen I and none in Regimens II and III. During 3 1/2 years of follow up, 13% of the cases in Regimen I, 1% in Regimen II, and 2% in Regimen III relapsed. Since the patients in the three regimens were otherwise comparable, it is concluded that the high inactivity rate, low relapse rate (1%-2%), and no early or late reaction as observed in Regimen II patients were because of adequate treatment.

Adult↗
PubMedDate not supplied

Assessment of viability by normal mouse foot-pad and bacillary ATP bioluminescence assay in multibacillary cases treated with an MDT regimen using conventional as well as newer drugs like minocycline and ofloxacin.

The therapeutic effect of a drug regimen of conventional drugs as well as newer drugs like ofloxacin and minocycline in smear-positive multibacillary (MB) leprosy cases was assessed by mouse foot-pad and ATP bioluminiscence methods. Biopsies were taken before starting treatment and after one year of treatment. They were processed for viability assessment by normal mouse foot-pad inoculation and bacillary ATP assay techniques. The test regimen was quite effective in its anti-bacterial effect as it was found to result in loss of bacillary viability in all the cases, as assessed by both methods.

Adenosine Triphosphate↗
PubMedDate not supplied

Patients presenting with defined areas of sensory loss--a preliminary study.

Thirty patients presenting with circumscribed areas of clearly demonstrable hypoesthesia were chosen from amongst those attending this Institute. Their history and clinical features were recorded, lepromin test was done for reading at four weeks, and peripheral part of the hypoesthetic area was biopsied for histopathology and immunostaining. The subjects were predominantly adult males with the symptomatic sites limited to the extremities. On routine histopathological examination of the symptomatic sites, the diagnosis of leprosy, using defined criteria, could be made in six cases (20%). Immunostaining of the remaining sections showing either no pathology or a nonspecific pathology revealed the presence of mycobacterial antigen in five of the 24 cases (20.83%). Overall, leprosy could be diagnosed in 11 of the 30 cases studied (36.66%). This study shows that leprosy may be an important cause of circumscribed areas of sensory deficit.

Adolescent↗