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V Sharma

Publications and source records attributed to V Sharma.

At least 73 records · Page 4Linked to original sources
PubMed2000

Self-report quality of life measure for people with schizophrenia: the SQLS.

BACKGROUND: Quality of life is the subject of growing interest and investigation. AIMS: To develop and validate a short, self-report quality of life questionnaire (the Schizophrenia Quality of Life Scale, SQLS). METHOD: People with schizophrenia in Liverpool were recruited via the NHS. Items, generated from in-depth interviews, were developed into an 80-item self-report questionnaire. Data were factor analysed, and a shorter form measure was tested for reliability and validity. This measure was administered together with other self-report measures--SF-36, GHQ-12 and HADS--to assess validity. RESULTS: Data were analysed to produce a final 30-item questionnaire, comprising three scales ('psychosocial', 'motivation and energy', and 'symptoms and side-effects') addressing different SQLS dimensions. Internal consistency reliability of the scale was found to be satisfactory. There was a high level of association with relevant SF-36, GHQ-12 and HADS scores. CONCLUSIONS: The SQLS was completed within 5-10 minutes. It possesses internal reliability and construct validity, and promises to be a useful tool for the evaluation of new treatment regimes for people with schizophrenia.

Adolescent↗
PubMed2000

Factors influencing infant visits to emergency departments.

OBJECTIVES: To follow the 1995 birth cohort of infants, born in the State of Missouri, through their first birthday to: 1) examine their rates of visits to emergency departments (EDs), 2) identify predictors of any ED visit, 3) examine rates of nonurgent ED visits, and 4) identify predictors of nonurgent visits. METHODS: This was a retrospective population cohort study. Using deterministic linkage procedures, 2 databases at the Missouri Department of Health (DOH; (the patient abstract database and the birth registry database) were linked by DOH personnel. International Classification of Diseases, Ninth Revision-Clinical Modification codes for ED visits were classified as emergent, urgent, or nonurgent by 2 researchers. Eight newborn characteristics were chosen for analysis. Negative binomial regression was used to examine the rates and predictors of both total and nonurgent ED visits. RESULTS: There were 935 total ED visits and 153 nonurgent ED visits per 1000 infant years. The average number of visits was.94, with 59% of infants having no visits, 21% having 1 ED visit, and 20% having 2 or more visits. Factors associated with increases in both total and nonurgent ED visits were Medicaid, self-pay, black race, rural region, presence of birth defects, and a nursery stay of >2 days. Significant interactions were found between Medicaid and race and Medicaid and rural regions on rates of ED use and nonurgent use. The highest rate of ED use, 1.8 per person year, was seen in white, rural infants on Medicaid, and the lowest rate (.4 per person year) was seen in urban white infants not on Medicaid. The highest rates of nonurgent use,.3 per person year, were among urban and rural Medicaid infants of both races and among black infants on commercial insurance. The lowest nonurgent rate,.04 per person year, was seen in white urban infants on commercial insurance. CONCLUSION: Infants in the State of Missouri have high rates of ED visits. Nonurgent visits are only a small portion of ED visits and cannot explain large variations in ED usage. Increased ED use by Medicaid patients may reflect continuing difficulties in accessing primary care.

Age Factors↗
PubMed2000

A comparative double-blind, randomised trial of a new second generation LMWH (bemiparin) and UFH in the prevention of post-operative venous thromboembolism. The Bemiparin Assessment group.

A randomised, prospective, double-blind trial was performed, to compare the safety and efficacy of a new low-molecular-weight heparin (LMWH) Bemiparin and standard unfractionated heparin (UFH), for the prophylaxis of postoperative venous thromboembolism. 300 patients scheduled to undergo elective hip arthroplasty were included. The principal outcome measures were the incidence of thromboembolic events and bleeding complications. 149 patients received 3,500 anti-Xa IU of bemiparin plus a placebo injection daily and 149 patients received 5,000 IU of UFH twice a day. The two groups were similar with respect to factors likely to affect the risk of developing post-operative venous thromboembolism (VTE) and risk of bleeding events. During the post-operative period, 34 patients developed VTE complications; 9 (7.2%) in the bemiparin group and 25 (18.7%) in the UFH group. VTE in the two groups was statistically significant (OR of 2.96; 95% CI 1.32-6.62 and p = 0.01). There were no significant differences in the frequency of bleeding complications: major bleeding requiring discontinuation of prophylaxis, (OR 1.21; 95% CI 0.36-4.05; p = 1.00), the measured median operative blood loss (p = 0.77) or the median postoperative drain loss (p = 0.97), and the number of patients who developed wound haematoma (OR 0.87; 95% CI 0.31-2.46; p = 1.00). A comparison of coagulation parameters on the preoperative day with post-operative day 2 +/- 1, day 6 +/- 1 and day of discharge showed a significantly higher AT concentration, anti-factor Xa activity and TFPI levels in the bemiparin group when compared with UFH. This study demonstrates that bemiparin, in a single daily subcutaneous dose of 3,500 anti-Xa IU in high risk patients undergoing hip arthroplasty is more effective than UFH administered twice daily at a dose of 5,000 IU in the prevention of postoperative VTE. Both agents are equally safe.

Aged↗
PubMed2000

IL-12 and IL-2 potentiate the in vitro tumor-specific activity of peripheral blood cells from cervical cancer patients.

We have carried out a detailed analysis of the cellular immune functions of cervical cancer patients in comparison with healthy controls. It has been observed that the freshly isolated peripheral blood mononuclear cells (PBMC) exhibit natural cytotoxicity (NC) against a number of targets including tumor cells, mainly delivered by NK cells, which are non-adoptive and MHC unrestricted. Upon stimulation with cytokines like IL-2, IL-7, IL-12, IL-15 and interferons, PBMC acquire lymphokine activated killer (LAK) activity which enables them to lyse a wide range of targets including fresh tumor cells and virally infected cells. We compared the effect of IL-2 and IL-12 on enhancement of NC of PBMC from cervical cancer patients. IL-12 stimulated cultures (CD3+, CD56+) exhibited significant levels of tumoricidal activity. IL-2 stimulated lytic activity sustained even after 10 days while that of IL-12 stimulated cells declined after 6 days. Activation of PBMC was marked by increase in the expression of activation marker CD45RO and adhesion molecules LFA-1alpha, ICAM-1 and CD44. Addition of IL-12 to IL-2 stimulated cultures further enhanced the degree of lytic activity. Our data, thus, provide an evidence that PBMC from cervical cancer patients can be stimulated in response to cytokines and local or systemic treatment with low doses of cytokines may help to yield a better immune response against virus infected tumor cells in cervical cancer.

Adult↗
PubMed2000

A cross-sectional survey of the clinical and psychological features of low back pain and consequent work handicap: use of the Quebec Task Force classification.

A hospital-based cross-sectional study examined 657 consecutive referrals with low back pain over two years to a district rheumatology service serving a population of about 250,000 people. Five hundred and thirty-eight had mechanical/degenerative low back pain. The mean age was 48.6 (range 18-80 SD 15.3) years; 64% were women. Patients with radiating pain or neurological deficit (Quebec Task Force classification) were significantly more disabled (Roland disability score p < 0.001) and depressed (Modified Zung score p < 0.05) than those without radiating pain. Women were more impaired (p = 0.02) than men but had similar disabilities (mean Roland score 11.7, range 0-24 SD 6.5). Fifty-three per cent of patients were receiving benefits and were significantly more likely to have musculoskeletal comorbidities than those in work (p < 0.025). It is concluded that the Quebec Task Force classification of low back pain impairment is a helpful descriptor and related to both physical and psychological disability and handicap in employment.

Adolescent↗
PubMed1999

Changes in electroporation thresholds of lipid membranes by surfactants and peptides.

This article reviews recent work from our laboratory that explores how chemical additives may alter the threshold of electroporation of synthetic lipid bilayers. The addition of the nonionic block copolymeric surfactant, poloxamer 188 (P188), at a concentration of 1 mM increased the electroporation thresholds of planar lipid bilayer membranes made of azolectin. For a 10-microsecond rectangular pulse, P188-treated membranes were found to have a statistically higher threshold voltage, longer latency time to rupture, and lower postpulse conductance. Addition of the nonionic surfactant, octaethyleneglycol-mono-n-dodecyl-ether (C12E8), decreased the electroporation threshold of bilayer membranes made of 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) by 10-40% for 10-microsecond- to 10-s-duration pulses, in a concentration-dependent manner over concentrations ranging from 0.1 to 10 mM. Postpulse membrane conductance also increased. The opposite effects of the two surfactants on electroporation thresholds may result from their very different structures, which would encourage different modes of surfactant-lipid interactions. To examine protein-lipid interactions and their effects on the electroporation threshold, the effects of a channel-forming polypeptide, gramicidin D (gD), was studied on membrane conductance and electroporation threshold. Electroporation thresholds for 15-ms pulses were unaffected by addition of gramicidin to POPC at a peptide:lipid concentration estimated to be 1:10,000, but increased significantly at ratios of 1:500 and 1:15, while membrane conductance increased monotonically with peptide concentration. A micropipette aspiration technique was applied to giant unilamellar POPC vesicles to measure changes in the membrane physical properties. When gD was added to give an estimated peptide:lipid ratio of 1:15, the membrane area expansivity modulus increased, indicating that the increase in electroporation threshold is correlated with a change in membrane stiffness. Thus, these findings demonstrate that surfactants or peptides can mediate the electroporation threshold of lipid bilayers.

1,2-Dipalmitoylphosphatidylcholine↗
PubMed1999

Diagnostic and prognostic potential of antibodies against O-acetylated sialic acids in canine visceral leishmaniasis.

Employing bovine submaxillary mucin (BSM) as the coating agent, an enzyme-linked immunosorbent assay (BSM-ELISA) was developed to detect antibodies directed against O-acetylated sialic acids (O-AcSA) in canine visceral leishmaniasis (CVL). Serum samples were collected from 50 dogs previously screened by a parasite-ELISA to detect anti-leishmanial antibodies and designated as seropositive (n = 30) and seronegative (n = 20). The BSM-ELISA detected anti-O-AcSA antibodies in 29 out of 30 seropositive dogs and was negative in 15 out of 20 seronegative dogs; the sensitivity and specificity of the assay being 96.6% and 75%, respectively. Seven dogs from an endemic area in central Israel were longitudinally monitored for 15 months clinically, serologically and cultured for parasite. The levels of antibodies directed against O-AcSA increased with the appearance of clinical symptoms and/or seropositivity, disappeared when the disease was self-limiting as also with chemotherapeutic response and reappeared with relapse. The BSM-ELISA, therefore, represents a valuable tool for assessment of disease progression.

Acetylation↗
PubMed1999

Prognostic role of p53 protein expression in epidermoid carcinoma of the anal canal.

PURPOSE: To assess the prognostic significance of p53 protein expression in patients with primary epidermoid carcinoma of the anal canal managed by radiation therapy (XRT), 5-fluorouracil (5-FU), and mitomycin C (MMC). METHODS AND MATERIALS: From January 1991 to December 1993, 58 consecutive patients with primary epidermoid carcinoma of the anal canal were treated in a prospectively designed protocol of XRT (24 Gy/12--3(1/2) wk split--28 Gy/14) and concurrent 5-FU (1000 mg/m2/day 1-4) and MMC (10 mg/m2 day 1) of each cycle of XRT. Paraffin-embedded tumor samples were unavailable in 9 patients, leaving 49 patients in the study. Expression of p53 protein was studied using immunohistochemistry and quantified as percent tumor nuclei showing positive staining. Actuarial survival and disease-free survival (DFS) rates were estimated by the Kaplan-Meier method, and compared using the log-rank test. A Cox proportional hazard model was used for the multivariable analysis. RESULTS: There were 6 T1, 26 T2, 7 T3, and 10 T4 lesions. Primary tumor sizes ranged from 1-15 cm with a median of 4 cm. There were 6 patients with nodal metastases. Median follow-up was 4.5 years. Positive nuclear immunostaining for p53 was observed in 40 of 49 patients. The median percent positive staining was 5%, with 13, 9, and 18 patients showing staining in <5%, 5 to <10%, and 10-50% of tumor nuclei respectively. There was no correlation of percent p53 staining with gender, age, tumor stage, size, or histology. Local, regional, and distant failures were observed in 12, 2, and 2 patients respectively. The 5-yr survival and DFS were 84% and 64% respectively. In univariate analysis, the only prognostic variable for survival was gender. For DFS, advanced T category and large tumor size were predictive of poor DFS. In multivariate analysis, poor DFS was associated with high T category (p = 0.0008), basaloid histology (p = 0.001), male gender (p = 0.002), and increasing percent of p53 protein expression (p = 0.01). CONCLUSIONS: It is concluded that expression for p53 protein is present in a high percentage of patients with epidermoid carcinoma of the anal canal. For patients managed with combined XRT, 5-FU, and MMC, percent p53 protein expression is of prognostic value for DFS independent of other clinical factors such as T category, gender, and histology.

Adult↗
PubMed1999

Human T-cell lymphotrophic virus type-I tax gene induces secretion of human macrophage inflammatory protein-1alpha.

Human T-cell lymphotropic virus I (HTLV-I) encodes for a 40-kDa protein, Tax, which is important for the immortalization of T cells. Tax has been shown to transactivate several cellular genes. In this study, we show that MIP-1alpha is selectively expressed and secreted in the tax transfected Jurkat cell line upon mitogen stimulation. Expression of MIP-1alpha-R mRNA in these cells suggests an autocrine role for this chemokine in HTLV-I infected T-cells. Induced MIP-1alpha expression and secretion in PMA/PHA stimulated tax transfected cells correlate with the noninduction of MNP-1 transcription factor, which is intimately involved in downmodulating the MIP-1alpha gene.

Autocrine Communication↗
PubMed1999

Unexpected divergence of enzyme function and sequence: "N-acylamino acid racemase" is o-succinylbenzoate synthase.

A protein identified as "N-acylamino acid racemase" from Amycolaptosis sp. is an inefficient enzyme (kcat/Km = 3.7 x 10(2) M-1 s-1). Its sequence is 43% identical to that of an unidentified protein encoded by the Bacillus subtilis genome. Both proteins efficiently catalyze the o-succinylbenzoate synthase reaction in menaquinone biosynthesis (kcat/Km = 2.5 x 10(5) and 7.5 x 10(5) M-1 s-1, respectively), suggesting that this is their "correct" metabolic function. Their membership in the mechanistically diverse enolase superfamily provides an explanation for the catalytic promiscuity of the protein from Amycolaptosis. The adventitious promiscuity may provide an example of a protein poised for evolution of a new enzymatic function in the enolase superfamily. This study demonstrates that the correct assignment of function to new proteins in functional and structural genomics may require an understanding of the metabolism of the organism.

Actinobacteria↗
PubMed1999

Importance of the carboxyl terminus in the folding and function of alpha-hemolysin of Staphylococcus aureus.

The physical state of two model mutants of alpha-hemolysin (alphaHL), alphaHL(1-289), a carboxyl-terminal deletion mutant (CDM), and alphaHL(1-331), a carboxyl-terminal extension mutant (CEM), were examined in detail to identify the role of the carboxyl terminus in the folding and function of native alphaHL. Denatured alphaHL can be refolded efficiently with nearly total recovery of its activity upon restoration of nondenaturing conditions. Various biophysical and biochemical studies on the three proteins have revealed the importance of an intact carboxyl terminus in the folding of alphaHL. The CDM exhibits a marked increase in susceptibility to proteases as compared with alphaHL. alphaHL and CEM exhibit similar fluorescence emission maxima, and that of the CDM is red-shifted by 9 nm, which indicates a greater solvent exposure of the tryptophan residues of the CDM. In addition, the CDM binds 8-anilino-1-naphthalene sulfonic acid (ANS) and increases its fluorescence intensity significantly unlike alphaHL and CEM, which show marginal binding. The circular dichroism studies point that the CDM possesses significant secondary structure, but its tertiary structure is greatly diminished as compared with alphaHL. These data show that the CDM has several of the features that characterize a molten globule state. Experiments with freshly translated mutants, using coupled in vitro transcription and translation, have further supported our observations that deletion at the carboxyl terminus leads to major structural perturbations in the water-soluble form of alphaHL. The studies demonstrate a critical role of the carboxyl terminus of alphaHL in attaining the native folded state.

Bacterial Toxins↗
PubMed1999

The quality of swallowing for patients with operable esophageal carcinoma: a randomized trial comparing surgery with radiotherapy.

BACKGROUND: Surgery is considered the standard treatment for operable esophageal carcinoma, although there is no compelling evidence that surgery can achieve better results than radiotherapy. There has previously been no direct randomized comparison of these two modalities with survival or disease specific outcome end points. METHODS: Ninety-nine patients with operable squamous cell carcinoma of the esophagus were randomly allocated to surgery or radiotherapy after stratification for tumor length (< or = or >5 cm). Those randomized to surgery underwent transthoracic esophagectomy with limited lymphadenectomy, whereas those in the radiotherapy arm received 50 gray in 28 fractions followed by a 15-gray boost to the primary tumor. Disease specific outcome was assessed for 4 subgroups: 1) disease specific symptoms, 2) physical symptoms, 3) ability to work, and 4) social/family interaction and global perception of disease specific outcome. The questionnaire was given prior to treatment and posttreatment at 3-month intervals for 1 year. Death was a secondary end point. RESULTS: There was an overall improvement in the quality of swallowing in both treatment arms after treatment and with the passage of time. The swallowing status was better in the surgery arm than in the radiotherapy arm at 6 months after treatment (P = 0.03, Fisher's exact test). Logistic regression analysis showed randomization arm (P = 0.035), time since treatment (P = 0.003), and pretreatment swallowing status to be significant determinants of posttreatment swallowing status. Surgery was twice as likely to result in improvement in swallowing than radiotherapy after correction for time and pretreatment swallowing status. Overall survival was better in the surgery arm than in the radiotherapy arm (P = 0.002, log rank test) (OR = 2.74 with 95% confidence intervals 1.51-4.98; P < 0.009, Cox proportional hazards model). CONCLUSIONS: Both surgery and radiotherapy can improve the quality of swallowing significantly for patients with operable esophageal carcinoma. Surgery is marginally superior to radiotherapy in improving the quality of swallowing. In this trial, survival in the surgery arm was significantly better than in the radiotherapy arm, although the small number of patients is a limitation.

Carcinoma, Squamous Cell↗
PubMed1999

Position jitter and undersampling in pattern perception.

The present paper addresses whether topographical jitter or undersampling might limit pattern perception in foveal, peripheral and strabismic amblyopic vision. In the first experiment, we measured contrast thresholds for detecting and identifying the orientation (up, down, left, right) of E-like patterns comprised of Gabor samples. We found that detection and identification thresholds were both degraded in peripheral and amblyopic vision; however, the orientation identification/detection threshold ratio was approximately the same in foveal, peripheral and amblyopic vision. This result is somewhat surprising, because we anticipated that a high degree of uncalibrated topographical jitter in peripheral and amblyopic vision would have affected orientation identification to a greater extent than detection. In the second experiment, we investigated the tolerance of human and model observers to perturbation of the positions of the samples defining the pattern when its contrast was suprathreshold, by measuring a 'jitter threshold' (the amount of jitter required to reduce performance from near perfect to 62.5% correct). The results and modeling of our jitter experiments suggest that pattern identification is highly robust to positional jitter. The positional tolerance of foveal, peripheral and amblyopic vision is equal to about half the separation of the features and the close similarity between the three visual systems argues against extreme topographical jitter. The effects of jitter on human performance are consistent with the predictions of a 'template' model. In the third experiment we determined what fraction of the 17 Gabor samples are needed to reliably identify the orientation of the E-patterns by measuring a 'sample threshold' (the proportion of samples required for 62.5% correct performance). In foveal vision, human observers are highly efficient requiring only about half the samples for reliable pattern identification. Relative to an ideal observer model, humans perform this task with 85% efficiency. In contrast, in both peripheral vision and strabismic amblyopia more samples are required. The increased number of features required in peripheral vision and strabismic amblyopia suggests that in these visual systems, the stimulus is underrepresented at the stage of feature integration.

Adult↗
PubMed1999

Sparse-sampling of gratings in the visual cortex of strabismic amblyopes.

Strabismic amblyopes show losses in positional acuity that cannot be explained by their resolution or contrast sensitivities. One hypothesis for these losses is a reduction in the density of cortical neurons that are driven by the amblyopic eye (cortical undersampling). The question this study addressed was whether the foveal representation of the amblyopic eye is undersampled in the cortex of strabismic amblyopes. In order to assess spatial sampling psychophysically, we recorded the perceived orientation of a stationary grating as a function of grating orientation and frequency in three strabismic amblyopes. To ensure high retinal contrast, the grating was imaged on the fovea of each observer using a laser interferometer. We found that the strabismic amblyopes misperceived the orientation of the grating at spatial frequencies that are a factor of two to six lower than the sampling frequency of the foveal cones. Since the retina and LGN in strabismic amblyopes are presumably normal, this result suggests sparse cortical sampling in the foveal representation of the amblyopic eye. Undersampling by cortical neurons may contribute to the spatial distortions present in strabismic amblyopic eyes.

Amblyopia↗
PubMed1999

Seasonality of manic depressive illness in Canada.

OBJECTIVE: The objective of the study was to determine if a seasonal pattern existed for hospital admissions of manic depressive illness to a Ontario provincial psychiatric hospital. METHOD: Admission records were reviewed for the 75 year period of the study. In the analysis factors including: mood state on admission, gender and the influence of psychotropic medications were considered. RESULTS: For mania and depression there was no statistically significant seasonal pattern of admissions. For mixed state admissions peaked in the summer. CONCLUSIONS: The results of this study contradict the seasonal pattern traditionally reported in the literature. The limitations of this study, which include changes in diagnostic criteria over time and admission date not identical to onset of affective episode, need to be acknowledged.

Adult↗
PubMed1999

Retrospective controlled study of inpatient ECT: does it prevent suicide?

BACKGROUND: This study examined the use of ECT among inpatients who committed suicide at a provincial psychiatric hospital. METHODS: A total of 45 psychiatric in-patients who committed suicide at a provincial psychiatric hospital were compared with a gender, age and admission diagnosis matched group of 45 hospitalized patients to examine the use of electroconvulsive therapy during the last 3 months of hospitalization. RESULTS: No difference in the utilization of ECT was found in the two groups. LIMITATIONS: Retrospective design and small sample size. CONCLUSIONS: We failed to demonstrate that ECT had prevented suicide in hospitalized patients. Future prospective studies with large sample size are needed to further examine this question.

Adult↗