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R Srinivasan

Publications and source records attributed to R Srinivasan.

At least 19 recordsLinked to original sources
PubMed2006

Post-traumatic fungal endophthalmitis--a prospective study.

PURPOSE: To study the incidence, clinical presentation, and the response of anti-fungals in cases of fungal endophthalmitis following open globe injury. METHODS: This is a prospective study of eight cases of post-traumatic fungal endophthalmitis among 110 patients who presented to us with open globe injury between August 2003 and January 2005. Patients with panophthalmitis were eviscerated and rest received intravitreal amphotericin B. Pars plana vitrectomy along with intravitreal miconazole was given in patients with inadequate response to intravitreal amphotericin. RESULTS: Two patients had panophthalmitis at the time of presentation and were eviscerated. Six different organisms were isolated from the culture of intraocular specimen of eight patients. The yield of vitreous aspirate was 87.5% and that of aqueous aspirate was 66.6%. Aspergillus sp. and Fusarium sp. were isolated in 62.5% of cases. Minimum inhibitory concentration of amphotericin B and miconazole was less than 3 microg/ml for all organisms except for Paecilomyces lilacinus and Fusarium solani, respectively. In total, 37.5% of patient had final visual acuity of 20/400 or better. CONCLUSIONS: Fungal endophthalmitis is a relatively rare complication of open globe injury. The final visual outcome after fungal endophthalmitis is dismal. Aspergillus fumigatus was found to be the most virulent organism. All organisms were found to be sensitive to amphotericin B, except P. lilacinus, which was sensitive to miconazole. Repeated intravitreal injection may be required to control the infection. The virulence of the organism and the site of injury are the main determinants of final visual outcome.

Adolescent↗
PubMed2006

Pathology of supraclavicular lymphadenopathy in Chandigarh, north India: an audit of 200 cases diagnosed by needle aspiration.

OBJECTIVE: Fine needle aspiration cytology (FNAC) of lymph nodes can be used routinely as a first-line diagnostic test. The majority of studies reveal a malignant cause for palpable supraclavicular lymph nodes. The present audit further emphasizes the use of FNAC as a first-line investigation for the evaluation of enlarged supraclavicular lymph nodes. METHODS: A total of 200 cases of palpable supraclavicular lymph node(s) were included in the present study. RESULTS: Left supraclavicular lymph nodes were found to be more commonly involved (59.5% cases). Sixty-four per cent cases showed metastatic deposits and 13.5% cases were diagnosed as tuberculosis. Ten per cent cases showed reactive lymphoid hyperplasia; 0.5% (one) case showed only necrosis and on autopsy, a microscopic focus of choriocarcinoma was found in the testis. In 7.5% cases, diagnostic material could not be aspirated despite repeated attempts. Common metastatic tumours were from lung (22% cases), breast (16.4% cases), cervix (11% cases) and oesophagus (8.6% cases). In 13.3% cases the primary site was unknown and the diagnosis of malignancy first came from FNAC. CONCLUSION: The present study further highlights the importance of FNAC as a first-line diagnostic modality in the evaluation of supraclavicular lymphadenopathy. A full history, radiological findings and immunochemistry in difficult cases can help to arrive at a definitive diagnosis.

Adolescent↗
PubMed2006

Fine needle aspiration of epididymal nodules in Chandigarh, north India: an audit of 228 cases.

BACKGROUND: Epididymal nodules are not infrequently encountered in surgical practice. These are generally small and slippery and fine needle aspiration cytology (FNAC) is not easy. But as it is rapid and less traumatic than a biopsy, this is a favoured technique in the assessment of epididymal nodules. PATIENTS AND METHODS: In the present study, all the cases of epididymal nodules aspirated from January 1998 to August 2004 were retrieved from the cytology files of the Department of Cytology, Post Graduate Institute of Medical Education and Research, Chandigarh, India. RESULTS: A total of 228 cases were retrieved and divided as follows: tuberculous epididymitis 70 (30.7%), non-specific inflammation 10 (4.4%), microfilaria 2 (0.9%), hydrocele 26 (11.4%), spermatocele 42 (18.4%), spermatic granulomas 12 (5.3%), adenomatoid tumour 3 (1.3%), leiomyosarcoma 1 (0.4%) and lipoma 1 (0.4%). Thirty-six (15.8%) cases were labelled as benign aspirate not otherwise specified. FNAC material was inadequate for opinion in 22 (9.65%) cases and three (1.3%) cases revealed evidence of a haematoma. CONCLUSIONS: FNAC was useful in the diagnosis of 90.3% of cases, thereby avoiding surgical biopsy and other investigations. Therefore, FNAC has an important role in the differential diagnosis of epididymal nodules as it can detect malignancy and benign conditions such as tuberculosis and acute and chronic epididymo-orchitis.

Biopsy, Fine-Needle↗
PubMed2006

The apolipoprotein E epsilon4 allele selectively increases the risk of frontotemporal lobar degeneration in males.

OBJECTIVE: To determine whether polymorphic variations in the apolipoprotein E gene (APOE) are associated with increased risk of frontotemporal lobar degeneration (FTLD) when mutation in tau gene is absent. METHODS: The APOE gene was genotyped by polymerase chain reaction from DNA routinely extracted from blood or brain tissues. The APOE epsilon4 allele frequency in 198 patients with FTLD not associated with mutations in tau gene was compared with that of a control group of 756 normal individuals drawn from the same geographical region. Analyses were done according to clinical subtype or sex. RESULTS: The APOE epsilon4 allele frequency (19.4%) was increased (p = 0.01) in FTLD v the whole control group (14.1%), while the APOE epsilon2 allele frequency in FTLD (6.5%) was slightly lower than in controls (8.0%) (NS). The APOE epsilon4 allele frequency in men with FTLD (22.3%) was greater (p = 0.002) than in male controls (12.3%); the frequency in women (16.3%) was similar to that in female controls (14.8%) (NS). The APOE epsilon2 allele frequency in men with FTLD was 4.9% while in male controls it was 9.5% (p = 0.06), but there was no difference in women (7.5% v 7.9%, NS). Neither the APOE epsilon2 nor APOE epsilon4 allele frequency varied significantly between any of the clinical subtypes. CONCLUSIONS: In FTLD not associated with mutations in tau gene, possession of APOE epsilon4 allele in men roughly doubles the chances of developing disease, whereas this has no impact upon disease risk in women.

Adult↗
PubMed2006

Muscoid fly populations in tsunami-devastated villages of southern India.

Several coastal villages of southern India were affected by the 26 December 2004 tsunami, and 10,749 people were killed. Investigation carried out in the affected villages during fourth, fifth, and sixth weeks posttsunami showed that the fly density was in the range of 12-91.8 flies per sweep net. In total, 3,259 flies belonging to eight species, namely, Musca domestica L., Musca vicina Macquart, Musca sorbens Wiedemann, Calliphora erythrocephala Robineau-Desvody, Sarcophaga ruficornis F., Chrysomyia sp. Robineau-Desvody, Chlorops sp., and Fannia sp. Robineau-Desvody, were recorded. M. domestica was the predominant species constituting 78.2% of the total flies collected. Density of flies was the highest in temporary shelters constructed for the victims, followed by centralized kitchens and devastated human settlements. Lack of waste control at centralized kitchens nearer to the shelters might be the reason for the high fly density in relief shelters. Under these circumstances, outbreak of fly-borne diseases is likely to be aggravated. Therefore, it is suggested that the ongoing space spraying be supplemented with effective waste control measures to reduce the high density of flies.

Animals↗
PubMed2006

Ultra low volume aerosol application of deltacide (deltamethrin 0.5% w/v, S-bioallethrin 0.71% w/v & piperonyl butoxide 8.9% w/v) against mosquitoes.

BACKGROUND & OBJECTIVE: Insecticide in the form of space spray as an ultra low volume (ULV) aerosol are used during epidemics of vector borne diseases. Deltacide, a formulation comprising of three chemicals viz., deltamethrin 0.5 per cent w/v, S-bio-allethrin 0.71 per cent w/v and piperonyl butoxide 8.9 per cent w/v is suitable for ULV application. As this combination is found to be effective in preventing resistance development tackling the population, which had already developed resistance and cause immediate mortality, its synergistic effect was tested in Peet Grady chamber, against three species of mosquitoes, viz., Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus. METHODS: Blood fed females were exposed to ULV application of deltacide in a Peet Grady chamber at four dosages viz., 0.005, 0.01, 0.02 and 0.04 ml/m2 and examined for knockdown activity at 10 min interval for 60 min. Thereafter, the mosquitoes were removed from the chamber and maintained in another room having controlled temperature (28+/-2 degrees C) and humidity (60-75%) and observed for recovery, if any, and the per cent knockdown was calculated. Mortality rate after 24 h of holding period was also determined from moribund and dead adults. RESULTS: Pairwise comparison showed that the effect of deltacide spray varied significantly (P<0.001) among the three species tested. The effectiveness was significantly higher in Ae. aegypti, when compared with that of Cx. quiquefasciatus (P<0.001) and An. stephensi (P<0.05). However, there was no significant difference in the efficacy of deltacide between Cx. quiquefasciatus and An. stephensi. All species of mosquitoes became inactive i.e., knocked down completely within 60 min of exposure at all the dosages tested and mortality observed was 100 per cent after 24 h of exposure. INTERPRETATION & CONCLUSION: Deltacide when tested in the form of ULV cold aerosol, the dosage 0.01 ml/m2 was effective against both Ae. aegypti, and An. stephensi, and 0.02 ml/m2 against Cx. quiquefasciatus, causing 100 per cent mortality. The efficacy of ULV application of deltacide against vector mosquitoes needs to be assessed under field conditions.

Aerosols↗
PubMed2005

Ethnic differences in selective neonatal BCG immunisation: white British children miss out.

BACKGROUND: Tuberculosis (TB) is a re-emerging problem, especially in the larger cities of Western Europe. Selective neonatal BCG vaccination is recommended for infants at risk of TB in the UK. Neonatal BCG is safe and effective, with an overall protective value of 75%. This study aimed to assess BCG rates among at risk infants in Cardiff and the Vale of Glamorgan, South Wales in the year 2003. METHODS: A cohort of infants at risk for TB was identified from demographic data stored on a computerised maternity activity database. A manual search of immunisation records determined overall rates and the rates for infants belonging to various ethnic groups. RESULTS: Of 5308 infants born in 2003, 514 (9.6%) were at risk of TB; 423 (82.2%) of these infants were referred postnatally for BCG vaccination and 391 received it. Twenty six of the 41 at risk white British infants missed having a BCG vaccination compared with 47 of 288 Asian infants and seven of 39 black African babies. The rate of BCG vaccination among white British infants was 36.5% compared with 83.6% for Asian infants from the Indian subcontinent (chi(2) = 7.25, p<0.01) and 82% for black African infants (chi(2) = 4.48, p<0.05). CONCLUSIONS: The overall BCG rate among at risk infants in Cardiff was 76% during the study period. The vaccination rate was poor among white British infants compared with other ethnic groups. Enhanced awareness of health professionals to recognise the need for vaccinating certain white children at risk of TB is essential to improve BCG coverage in an increasingly multiethnic population.

Africa↗
PubMed2005

How long does it take for tuberculosis to cause secondary amyloidosis?

It is often believed that secondary amyloidosis occurs months to years after the onset of the predisposing cause. We describe two cases that, to the best of our knowledge, are the earliest described cases of amyloidosis occurring after the diagnosis of active tuberculosis.

Journal Article↗
PubMed2005

Accelerated penalized weighted least-squares and maximum likelihood algorithms for reconstructing transmission images from PET transmission data.

We present penalized weighted least-squares (PWLS) and penalized maximum-likelihood (PML) methods for reconstructing transmission images from positron emission tomography transmission data. First, we view the problem of minimizing the weighted least-squares (WLS) and maximum likelihood objective functions as a sequence of nonnegative least-squares minimization problems. This viewpoint follows from using certain quadratic functions as surrogate functions for the WLS and maximum likelihood objective functions. Second, we construct surrogate functions for a class of penalty functions that yield closed form expressions for the iterates of the PWLS and PML algorithms. Due to the slow convergence of the PWLS and PML algorithms, accelerated versions of them are developed that are theoretically guaranteed to monotonically decrease their respective objective functions. In experiments using real phantom data, the PML images produced the most accurate attenuation correction factors. On the other hand, the PWLS images produced images with the highest levels of contrast for low-count data.

Algorithms↗
PubMed2005

Persistence of recipient plasma cells and anti-donor isohaemagglutinins in patients with delayed donor erythropoiesis after major ABO incompatible non-myeloablative haematopoietic cell transplantation.

Delayed donor erythropoiesis and pure red-cell aplasia (PRCA) complicate major-ABO mismatched non-myeloablative allogeneic stem-cell transplantation. To characterize these events, we analysed red-cell serology and chimaerism in lymphohaematopoietic lineages, including plasma cells and B cells, in 12 consecutive major-ABO incompatible transplants following cyclophosphamide/fludarabine-based conditioning. Donor erythropoiesis was delayed to more than 100 days in nine (75%) patients including six (50%) who developed PRCA. During PRCA, all patients had persistent anti-donor isohaemagglutinins and recipient plasma cells (5-42%), while myeloid and T cells were completely donor in origin. In contrast, B-cell chimaerism was frequently full-donor when significant anti-donor isohaemagglutinins persisted. Four patients with early mixed haematopoietic chimaerism and the prolonged presence of anti-donor isohaemagglutinins and recipient plasma cells developed delayed-onset (>100 days post-transplant) red cell transfusion dependence and PRCA after myeloid chimaerism converted from mixed to full donor. These findings confirm that donor-erythropoiesis is impacted by temporal disparities in donor immune-mediated eradication of recipient lymphohaematopoietic cells during major-ABO incompatibility and suggest that plasma cells are relatively resistant to graft-versus-host haematopoietic effects.

Adult↗
PubMed2005

Nephrotic syndrome: an under-recognised immune-mediated complication of non-myeloablative allogeneic haematopoietic cell transplantation.

Nephrotic syndrome (NS) is an extremely rare complication of myeloablative allogeneic haematopoietic cell transplantation (HCT) that usually occurs in association with chronic graft-versus-host disease (C-GVHD). We observed an unexpectedly high incidence of NS in a cohort of 163 consecutive patients undergoing non-myeloablative HCT from a related human leucocyte antigen-compatible donor. Seven patients developed NS at a median 318 d post-transplant (range 119-1203 d; cumulative incidence 6.1%). The median age at onset of NS was 46 years (range 33-59 years); three of the seven patients had no evidence of C-GVHD while four had accompanying limited C-GVHD. At diagnosis, median proteinuria was 16.5 g/24 h (range 3-24 g/24 h). Renal biopsy was performed in four cases and revealed membranous nephropathy. NS was not always associated with other symptoms of C-GVHD, and in contrast to previous reports, usually did not improve with the re-initiation of aggressive immunosuppression, resulting in progressive renal failure necessitating dialysis in three of seven cases. Membranous nephropathy resulting in NS is a previously unrecognised and clinically significant complication of non-myeloablative HCT.

Adolescent↗