Search PubMed⌕ Search

Biomedical subjects

M Srinivasan

Publications and source records attributed to M Srinivasan.

At least 163 records · Page 9Linked to original sources
PubMedDate not supplied

Persistently elevated AFP and AChE in amniotic fluid from a normal fetus following demise of its twin.

Intrauterine fetal demise (IUFD) in one of twins at 12 weeks of gestation was accompanied by markedly elevated maternal serum alpha-fetoprotein (AFP) at 17 and 18 weeks. Amniotic fluid AFP from the healthy surviving twin's sac at 18.5 and 23 weeks was also greatly increased along with a positive acetylcholinesterase (AChE) band. Persistently elevated AFP and positive AChE so long after fetal demise--6.5 and 11 weeks post IUFD--has not, to our knowledge, been previously described. In similar cases, high level ultrasound and careful placental examination at birth should be utilized to search for fetal abnormalities or multiple pregnancy with IUFD.

Acetylcholinesterase↗
PubMedDate not supplied

Mycotic keratitis: susceptibility to antiseptic agents.

Oculomycosis is a severe problem in most developing countries. Specific antifungal agents are often unavailable, and are expensive. The use of antiseptic agents was therefore explored. Fungal isolates from patients in India and Ghana were tested against chlorhexidine, povidone iodine, propamidine, and polyhexamethylenebiguanide, and compared with econazole by placing the drugs in wells made in Sabouraud's agar plates seeded with the test organism. Fungal sensitivity testing is a contentious area but this method is simple and cheap. Chlorhexidine showed a good dose related response, povidone iodine showed a good response at all concentrations and econazole was the most effective in vitro. A small pilot study was conducted in India to assess clinical efficacy for fungal corneal ulcers. Both chlorhexidine and econazole proved effective but povidone iodine was ineffective. We suggest that chlorhexidine may be a useful first line agent for fungal keratitis when other antifungals are not available.

Anti-Infective Agents, Local↗
PubMedDate not supplied

A study of the spectrum of Acanthamoeba keratitis: a three-year study at a tertiary eye care referral center in South India.

PURPOSE: To determine the epidemiological and clinical characteristics of Acanthamoeba keratitis and also to determine the sensitivity and specificity of smears in the detection of Acanthamoeba. MATERIALS AND METHODS: A retrospective review of all culture-positive cases of Acanthamoeba keratitis seen between October 1999 and August 2002 was performed. Corneal scrapes were subjected to culture and microscopy using standard protocols. RESULTS: Out of 3183 consecutive patients with clinically diagnosed corneal ulcers evaluated, 33 (1.04%) were found to be due to Acanthamoeba. Twenty-four out of 33 (72.72%) were less than 51 years of age (P<0.001). All patients were from rural areas (P<0.001) and 26 (78.79%) of them were agricultural workers (P=0.031). All 33 had history of corneal injury (P<0.001) and 28 (84.85%) patients had injury with mud (P<0.001). All 33 (100%) patients had previous medical treatment (P=0.009) and 10 (30.3%) had used traditional eye medicines (P=0.183). A clinical pattern of ring infiltrate was characteristic in 15 (45.45%) patients. The diameter of the corneal ulcer was more than 6 mm in 27 (81.82%) eyes (P<0.001). Twenty-six (78.79%) patients had visual acuity of perception of light on initial presentation (P<0.001) and 24 (72.73%) had the same as their final visual outcome. The sensitivity of 10% potassium hydroxide (KOH) preparation was found to be higher (P<0.001) in the detection of Acanthamoeba cysts. CONCLUSION: The incidence of Acanthamoeba keratitis amongst the corneal ulcer patients was 1% in this setting and it was mainly due to corneal injury by mud. The KOH preparation is a sensitive diagnostic tool for the detection of Acanthamoeba. Delayed diagnosis or misdiagnosis and inappropriate antimicrobial therapy results in poor visual outcome.

Acanthamoeba Keratitis↗
PubMedDate not supplied

Recognition of cyclooxygenase-2 (COX-2) active site by NSAIDs: a computer modelling study.

The energetics and models of COX-2 complexed with nonsteroidal anti-inflammatory drugs (NSAIDs) having different degrees of selectivity for two isoforms of COX (COX-2 and COX-1) have been studied using computer modelling approach. The models are obtained for complexes of NS398 (NS), a selective COX-2 inhibitor; indoprofen (Ind), a non-selective inhibitor; di-tert-butylbenzofurans (DHDMBFs) with substituents at the 5th position: CONH(CH2)2OMe (BF1), CONH-c-Pr (BF2), 3-methylene-gamma-butyrolactonyl (BF3) and oxicams namely, meloxicam (Mel), piroxicam (Pir) and tenoxicam (Ten). These were optimized using molecular mechanics (MM) and molecular dynamics (MD) techniques. The binding energies and structures were compared with pharmacological parameters and available results with COX-1. In case of NS a larger difference in the binding energies between COX-2 and COX-1 was noticed as compared to that of Ind. It also had stronger interaction with His90 and Tyr355 which is considered important for COX-2 selectivity. There was a difference in the compactness at the channel entrance between COX-2 selective and non-selective ligands. Models with DHDMBFs and oxicams showed a similar correlation. The results were used to design a peptide inhibitor, Tyr-Arg-Cys-Ala-delta Phe-Cys (Pept) which could fit better in the COX-2 cavity. As per our MD simulation results this peptide inhibitor showed both higher activity and COX-2 selectivity.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMedDate not supplied

Expulsive choroidal haemorrhage.

Expulsive choroidal haemorrhage is a dramatic and serious complication of cataract surgery that occurred in five patients out of ten thousand consecutive cataract surgeries performed by the author during the year 1989 and 1990. Report about this dreaded complication after cataract surgery are scanty and as far as I can remember I have not seen any report in Indian ophthalmic literature recently. Since cataract surgery forms the major part of intra ocular surgeries performed in our country, I thought it would be appropriate to report about this rare complication which may occur to all of us. Out of five cases 3 were males and 2 were females in the age group ranging between 45-72 years. Two eyes regained vision up to 6/12 after intra operative expulsive haemorrhage. All the eyes were salvaged by doing anterior sclerotomy. Diabetes, hypertension, glaucoma and myopia are the commonest predisposing factors.

Aged↗
PubMedDate not supplied

Assessment of severity of aortic stenosis by continuous wave Doppler echocardiography.

Fifty consecutive patients with aortic stenosis were evaluated by continuous wave Doppler echocardiography for assessment of the transaortic gradient. The Doppler derived gradients were compared with the gradients measured at cardiac catheterisation. Excellent correlation was found between the Doppler and catheterisation findings for the maximum instantaneous gradient (r = 0.92) and the mean systolic gradient (r = 0.84). The maximum, midsystolic and late systolic Doppler gradients also showed a good correlation with the peak to peak catheter gradient. The maximum Doppler velocity however, showed overestimation of the peak to peak gradient in the presence of mild aortic stenosis (predictive accuracy 86%). The midsystolic Doppler velocity showed the highest predictive accuracy (94%) for the detection of severe aortic stenosis. No case of severe aortic stenosis was missed by Doppler using either the maximum or midsystolic Doppler velocity. These findings indicate that continuous wave Doppler ultrasound provides a reliable estimate of the gradient in patients with aortic stenosis.

Adolescent↗