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S Sharma

Publications and source records attributed to S Sharma.

At least 361 records · Page 20Linked to original sources

Arteriovenous adventitial sheathotomy for the treatment of macular edema associated with branch retinal vein occlusion.

PURPOSE: To report arteriovenous adventitial sheathotomy for treatment of macular edema associated with branch retinal vein occlusion. METHODS: Case reports with review. Five eyes of five patients with best-corrected visual acuity of less than 20/200 secondary to branch retinal vein occlusion had pars plana vitrectomy and arteriovenous adventitial sheathotomy and were followed postoperatively for a mean of 6.5 years (range, 5 to 7 years). RESULTS: In four of five eyes, the best-corrected visual acuity improved to 20/30 to 20/70. In the remaining eye, visual acuity remained at finger counting secondary to macular ischemia. CONCLUSION: Arteriovenous adventitial sheathotomy may be beneficial for select patients with poor vision secondary to branch retinal vein occlusion.

Aged↗

Difference between ophthalmologists' and patients' perceptions of quality of life associated with age-related macular degeneration.

BACKGROUND: There may be a wide disparity between the perceptions of patients and those of their treating physicians concerning the quality of life associated with a given state of health. Because of this potential for difference of opinion, we performed a study to evaluate patients' and ophthalmologists' perceptions of quality of life, as measured by utility analysis, associated with visual loss secondary to age-related macular degeneration (AMD). METHODS: Cross-sectional study. Utilities were assessed, by means of both the time trade-off method and the standard gamble method, for various degrees of theoretical visual loss secondary to AMD for ophthalmologists-in-training and graduate ophthalmologists. These were compared to utilities for a known population of patients with actual visual loss due to AMD. A utility of 1.0 is associated with perfect health, whereas a utility of 0.0 is associated with death. RESULTS: With both the time trade-off and standard gamble methods, the patients had lower mean utilities than did the ophthalmologists for the same degrees of visual loss secondary to AMD. The ophthalmologists were significantly less willing than the patients to trade years of remaining life for perfect vision with the time tradeoff method (p < or = 0.01), and with the standard gamble method they were less willing than the patients to take the risk of dying in return for perfect vision. Given the scenario of counting fingers or worse vision in both eyes, the ophthalmologists were willing to trade 3.3 of every 10 years of remaining life for perfect vision in both eyes, whereas the patients with actual vision of counting fingers or worse in both eyes were willing to trade 6.0 of every 10 years of remaining life for this result. INTERPRETATION: When presented with the scenario of visual loss secondary to AMD, ophthalmologists substantially underestimated its effect on patients' quality of life.

Adult↗

Converting visual acuity to utilities.

BACKGROUND: Utility theory can be used to quantify dysfunction associated with various diseases and thus can represent a "hard" measure of quality of life. By determining utility values, one can compare the quality of life of patients with ocular disease to that of patients with non-ophthalmic problems. We performed a study to determine whether utility values from patients with ocular disease are associated with clinical variables, including visual acuity in the better-seeing eye, and to develop a mathematical method for converting visual acuity to utility value, if there is an association between the two. METHODS: Cross-sectional study. A total of 239 patients from a tertiary care retinal practice with various ocular conditions, including macular degeneration, cataract, glaucoma and diabetic retinopathy, were interviewed under standardized conditions to determine their utility values by the time trade-off technique. Visual acuity, duration of visual loss and number of concomitant conditions were also determined. Multiple linear regression was performed to determine which variables were associated with utility values. RESULTS: The mean acuity in the better-seeing eye was 0.479 (near 20/40 vision). The mean utility value was 0.72. Accordingly, the average patient in our series was willing to trade 2.8 of every 10 remaining years of life to obtain perfect vision in both eyes. Utility value was significantly associated with visual acuity in the better-seeing eye (F = 69.1, p < 0.001). Other variables were not significantly associated with utility value. The association with duration of visual loss approached statistical significance (p = 0.075). Utility values (U) for patients with ocular disease can be derived from the following formula: U = (0.374)(visual acuity in better-seeing eye) + 0.514. INTERPRETATION: Utility values from patients with ocular disease were strongly associated with visual acuity and could be estimated mathematically.

Aged↗

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Journal Article↗

Biotransformation of lantadenes, the pentacyclic triterpenoid hepatotoxins of lantana plant, in guinea pig.

Oral administration of lantana (Lantana camara var. aculeata) leaf powder to guinea pigs at a dose of 6 g/ kg body weight elicited cholestasis. The animals were euthanized 48 h after dosing. Liver homogenates, bile, gall bladder, blood, urine, contents of gastrointestinal tract (GIT) and faeces were analysed for the principal hepatotoxin in lantana leaves viz. lantadene A (LA), its congeners and biotransformation products, using high performance liquid chromatographic technique. Lantadenes could not be detected in liver, bile, gall bladder, blood and urine samples. LA and lantadene B (LB), their derivatives reduced lantadene A (RLA), reduced lantadene B (RLB) and two unidentified metabolites could be detected in the contents of lower GIT and faeces. In vitro incubation of lantana leaf powder with guinea pig caecal contents under anaerobic conditions elicited biotransformation of LA and LB to RLA and RLB, respectively. On the other hand, incubation of lantana leaf powder with cattle rumen liquor under anaerobic conditions did not elicit biotransformation of lantadenes.

Anaerobiosis↗

Incremental cost effectiveness of laser photocoagulation for subfoveal choroidal neovascularization.

OBJECTIVE: To perform a patient preference-based, incremental cost-effectiveness analysis for laser treatment of subfoveal choroidal neovascularization. DESIGN: Computer-based econometric modeling. METHODS: The cost effectiveness of laser photocoagulation therapy was compared with the natural course of subfoveal choroidal neovascularization. The model applied long-term visual data from previous clinical trials, utility analysis (which reflects patient perceptions of quality of life associated with a health state), decision analysis with Markov modeling, and the economic principles of present value analysis with discounting to account for the time value of money. DATABASE: Data from patients eligible for treatment of subfoveal choroidal neovascularization obtained by researchers in the Macular Photocoagulation Study were used for the analysis. INTERVENTION: Modeled laser therapy for subfoveal choroidal neovasacularization in patients with age-related macular degeneration. MAIN OUTCOME MEASURE: Cost per quality-adjusted life-year ($/QALY gained) associated with laser therapy. RESULTS: Laser photocoagulation therapy for subfoveal choroidal neovascularization, as compared with no treatment, resulted in a mean gain of 0.257 QALYs per treated patient. Using a yearly discount rate of 3% to account for the time value of money and inflation, the resultant $/QALY gained was $5629. Sensitivity analysis used in the cost-effectiveness analysis resulted in a $/QALY gained of $4974 with no gained discount rate and $11,633 with a yearly discount rate of 10%. CONCLUSIONS: The incremental expense of laser therapy for the treatment of subfoveal choroidal neovascularization appears to be highly cost effective. The result, which takes into account patient preference-based utility data, compares quite favorably with other interventional therapies across different medical specialties.

Aged↗

Visual outcomes following the use of intravitreal steroids in the treatment of postoperative endophthalmitis.

OBJECTIVE: To compare visual outcomes between cases of acute postoperative endophthalmitis that did or did not receive intravitreal steroids. DESIGN: Retrospective nonrandomized comparative trial. PARTICIPANTS: Fifty-seven patients with postoperative endophthalmitis. INTERVENTION: Thirty-one patients with postoperative endophthalmitis resulting from cataract extraction received both intravitreal antibiotics and steroids, whereas the remaining 26 received only intravitreal antibiotics. MAIN OUTCOME MEASURES: Improvement in visual acuity. RESULTS: Multivariate logistic regression was used to analyze the variables that potentially influence a three-line visual acuity improvement. The mean baseline visual acuities of both groups were comparable. The use of intravitreal steroids reduced the probability of developing a three-line improvement in visual acuity (odds ratio [OR] = 0.287; 95% confidence interval [CI] [0.072-0.852]). On the basis of logistic regression analysis using our multivariate model, gender, baseline visual acuity, and pars plana vitrectomy were not significantly associated with visual outcome differences between the two groups. CONCLUSIONS: Patients who received intravitreal steroids had a significantly reduced likelihood of obtaining a three-line improvement in visual acuity. At a minimum our study provides no support for their use and, therefore, steroids may not be efficacious for acute endophthalmitis related to cataract extraction.

Acute Disease↗

Levels of lantadenes, bioactive pentacyclic triterpenoids, in young and mature leaves of Lantana camara var. aculeata.

Levels of the lantadene pentacyclic triterpenes were quantified in young and mature leaf samples of Lantana camara var. aculeata, by HPLC. The amount of different lantadenes (mg/100 g dry wt.) in young and mature leaf samples, respectively, was: lantadene A, 491.5 +/- 6.3, 805.9 +/- 52.8; lantadene B, 347.0 +/- 3.0, 522.3 +/- 37.1; lantadene C, 191.3 +/- 10.3, 424.8 +/- 39.1; lantadene D, 49.7 +/- 5.3, 177.4 +/- 19.0; reduced lantadene A, 19.1 +/- 2.3, 28.7 +/- 4.5; reduced lantadene B, 13.0 +/- 1.3, 18.6 +/- 1.2; and 22 beta-hydroxyoleanonic acid, 82.5 +/- 11.4, 167.7 +/- 30.1.

Chromatography, High Pressure Liquid↗

Utility of metabolic exercise testing in distinguishing hypertrophic cardiomyopathy from physiologic left ventricular hypertrophy in athletes.

OBJECTIVES: This study evaluated the role of metabolic (cardiopulmonary gas exchange) exercise testing in differentiating physiologic LVH in athletes from HCM. BACKGROUND: Regular intensive training may cause mild increases in left ventricular wall thickness (LVWT). Although the degree of left ventricular hypertrophy (LVH) is typically less than that seen in hypertrophic cardiomyopathy (HCM), genetic studies have shown that a substantial minority of patients with HCM have an LVWT in the same range. The differentiation of physiologic and pathologic LVH in this "gray zone" can be problematic using echocardiography and electrocardiography alone. METHODS: Eight athletic men with genetically proven HCM and mild LVH (13.9 +/- 1.1 mm) and eight elite male athletes matched for age, size and LVWT (13.4 +/- 0.9 mm) underwent symptom limited metabolic exercise stress testing. Peak oxygen consumption (pVO2), anaerobic threshold, oxygen pulse and respiratory exchange ratios were measured in both groups and compared with those observed in 12 elite and 12 recreational age- and size-matched athletes without LVH. RESULTS: Elite athletes with LVH had significantly greater pVO2 (66.2 +/- 4.1 ml/kg/min vs. 34.3 +/- 4.1 ml/kg/min; p < 0.0001), anaerobic threshold (61.6 +/- 1.8% of the predicted maximum VO2 vs. 41.4 +/- 4.9% of the predicted maximum VO2; p < 0.001) and oxygen pulse (27.1 +/- 3.2 ml/beat vs. 14.3 +/- 1.8 ml/beat; p < 0.0001) than individuals with HCM. A pVO2 >50 ml/kg/min or >20% above the predicted maximum VO2 differentiated athlete's heart from HCM. CONCLUSIONS: Metabolic exercise testing facilitates the differentiation between physiologic LVH and HCM in individuals in the "gray zone."

Adolescent↗

Sudden death in hypertrophic cardiomyopathy: identification of high risk patients.

OBJECTIVES: We sought to identify patients with hypertrophic cardiomyopathy (HCM) at high risk of sudden death (SD). BACKGROUND: Relatively low mortality rates in HCM make conventional analysis of multiple clinical risk markers for SD problematic. This study used a referral center registry to investigate a smaller number of generally accepted noninvasive risk markers. METHODS: We studied 368 patients (14 to 65 years old, 239 males) with HCM. There were five variables: nonsustained ventricular tachycardia (NSVT), syncope, exercise blood pressure response (BPR), family history of sudden death (FHSD) and left ventricular wall thickness (LVWT). RESULTS: During follow-up (3.6+/-2.5 years [range 2 days to 9.6 years]), 36 patients (9.8%) died, 22 of them suddenly. Two patients received heart transplants. The six-year SD-free survival rate was 91% (95% confidence interval [CI] 87% to 95%). In the Cox model, there was a significant pairwise interaction between FHSD and syncope (p = 0.01), and these were subsequently considered together. The multivariate SD risk ratios (with 95% CIs) were 1.8 for BPR (0.7 to 4.4) (p = 0.22); 5.3 for FHSD and syncope (1.9 to 14.9) (p = 0.002); 1.9 for NSVT (0.7 to 5.0) (p = 0.18) and 2.9 for LVWT (1.1 to 7.1) (p = 0.03). Patients with no risk factors (n = 203) had an estimated six-year SD-free survival rate of 95% (95% CI 91% to 99%). The corresponding six-year estimates (with 95% CIs) for one (n = 122), two (n = 36) and three (n = 7) risk factors were 93% (87% to 99%), 82% (67% to 96%) and 36% (0% to 75%), respectively. Patients with two or more risk factors had a lower six-year SD survival rate (95% CI) compared with patients with one or no risk factors (72% [56% to 88%] vs. 94% [91% to 98%]) (p = 0.0001). CONCLUSIONS: This study demonstrates that patients with multiple risk factors have a substantially increased risk of SD sufficient to warrant consideration for prophylactic therapy.

Adult↗

Fungal keratitis after laser in situ keratomileusis.

A 22-year-old woman presented with pain, redness, watering, and decrease in vision in her left eye 15 days after laser in situ keratomileusis for myopia. Slitlamp examination showed a central full-thickness infiltrate with hyphate edges. Microscopic examination of corneal scrapings from the edge and underneath the flap showed fungal filaments, and the growth on culture media was identified as Scedosporium apiospermum.

Adult↗

The effects of early rearing environment on the development of GABAA and central benzodiazepine receptor levels and novelty-induced fearfulness in the rat.

We compared the effects of handling or maternal separation from the day following birth until postnatal day 14 on behavioral responses to novelty and on GABAA and central benzodiazepine (CBZ) receptor levels in the rat. As adults, handled animals showed reduced startle responsivity, increased exploration in a novel open field, and decreased novelty-induced suppression of feeding relative to the handled (H) and/or maternal separation (MS) groups. As compared with handled animals, both nonhandled (NH) and MS animals displayed: (1) reduced GABAA receptor levels in the locus coeruleus (LC) and the n. tractus solitarius (NTS); (2) reduced CBZ receptor sites in the central and lateral n. of the amygdala, the frontal cortex, and in the LC and NTS; and (3) reduced levels of the mRNA for the gamma 2 subunit of the GABAA receptor complex, which confers high affinity BZ binding, in the amygdaloid nuclei as well as in the LC and NTS. Both the amygdala and the ascending noradrenergic systems have been considered as critical sites for the anxiolytic effects of benzodiazepines. These data suggest that early life events influence the development of the GABAA receptor system, thus altering the expression of fearfulness in adulthood.

Acoustic Stimulation↗

Randomized controlled trial of doxycycline prophylaxis against leptospirosis in an endemic area.

Leptospirosis occurs as seasonal outbreaks, lasting for about 3 weeks during October-November in North Andaman. A randomized controlled trial was undertaken to assess the efficacy of doxycycline prophylaxis in the prevention of infection and clinical disease due to leptospires during the outbreak period. A sample population of 782 persons, randomized into two groups was given doxycycline 200 mg/week and a placebo. The microscopic agglutination test was done on blood samples collected on day zero, after 6 weeks and after 12 weeks. Infection rates and attack rates of clinical illness were calculated in the two groups based on the serological results. Statistically there was no difference in the infection rates among the two groups. However, a statistically significant difference was observed in the clinical disease attack rates (3.11 vs. 6.82%) between study group and control group. The results of the study indicate that doxycycline prophylaxis does not prevent leptospiral infection in an endemic area, but has a significant protective effect in reducing the morbidity and mortality during outbreaks.

Adolescent↗

Posttranslational regulation of IRF-4 activity by the immunophilin FKBP52.

Interferon regulatory factor-4 (IRF-4) plays an important role in immunoregulatory gene expression in B and T lymphocytes and is also highly expressed in human T cell leukemia virus type 1 infected cells. In this study, we characterize a novel interaction between IRF-4 and the FK506-binding protein 52 (FKBP52), a 59 kDa member of the immunophilin family with peptidyl-prolyl isomerase activity (PPIase). IRF-4-FKBP52 association inhibited IRF4-PU.1 binding to the immunoglobulin light chain enhancer E(lambda2-4) as well as IRF-4-PU.1 transactivation, effects that were dependent on functional PPIase activity. FKBP52 association also resulted in a structural modification of IRF-4, detectable by immunoblot analysis and by IRF-4 partial proteolysis. These results demonstrate a novel posttranslational mechanism of transcriptional control, mediated through the interaction of an immunophilin with a transcriptional regulator.

Amino Acid Sequence↗

One step purification of peanut phospholipase D by precipitation with alginate.

A simple titrimetric assay with soybean lecithin has been used for screening phospholipase D activity from some plant sources, viz. peanut, wheat germ, cabbage and carrot. The enzyme from peanut has been purified by binding to alginate which is a water soluble polymer. The purification consisted of co-precipitation of enzyme with alginate upon addition of 0.06 M Ca++. The enzyme was eluted from the polymer using 0.2 M sodium chloride. The activity recovery was 61% with 34 fold purification.

Alginates↗