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Biomedical subjects

S Saxena

Publications and source records attributed to S Saxena.

At least 91 records · Page 5Linked to original sources
PubMed1999

Selecting national items for the WHOQOL: conceptual and psychometric considerations.

The WHOQOL is a new measure designed to assess quality of life cross-culturally in health and health care. An international core of 276 items covering 29 facets of quality of life organised into 6 domains has been established conceptually and then assessed in psychometric terms. The method also allowed for the inclusion of extra national items to enable the concept of quality of life to be complete for each language and culture and to achieve conceptual equivalence between different language versions in participating centres. The present study investigates the properties of these national items using data obtained from 3740 participants world-wide, who completed the instrument in 10 of 16 original WHOQOL centres. Five statistical criteria were applied to 144 national items to examine their performance in competition with internationally agreed core items from the same facet, using data obtained from within that centre. Multi-dimensional scaling and cluster analysis was used to examine the structural relationship of national items within their own facet and directed their inclusion. Forty (29%) national items were selected and detailed examples demonstrate the selection methods used. They show how entirely new facets as well as individual items can be assessed for appending to the core WHOQOL-100. They also enable ambiguity to be resolved where there may be doubt about whether proposed items constitute part of an existing facet or justify a new one. Where national items are similar in more than one centre, a mechanism is provided whereby these items can be re-evaluated as candidates for inclusion in any future revision of the international core. Lastly, a case is identified that may provide justification for the establishment of national facets.

Adolescent↗
PubMed1999

Localized orbitofrontal and subcortical metabolic changes and predictors of response to paroxetine treatment in obsessive-compulsive disorder.

Previous positron emission tomography (PET) studies of patients with obsessive-compulsive disorder (OCD) have found elevated glucose metabolic rates in the orbitofrontal cortex (OFC) and caudate nuclei that normalize with response to treatment. Furthermore, OCD symptom provocation differentially activates specific subregions of the OFC, which have distinct patterns of connectivity and serve different functions. Therefore, we sought to determine the role of specific subregions of the OFC and associated subcortical structures in mediating OCD symptoms, by determining how glucose metabolism in these structures changed with paroxetine treatment of OCD patients. We also sought to determine whether pretreatment OFC metabolism would predict response to paroxetine, as it has for other OCD treatments. Twenty subjects with OCD received [18F]-fluorodeoxyglucose (FDG)-PET scans before and after 8 to 12 weeks of treatment with paroxetine, 40 mg/day. In patients who responded to paroxetine, glucose metabolism decreased significantly in right anterolateral OFC and right caudate nucleus. Lower pretreatment metabolism in both left and right OFC predicted greater improvement in OCD severity with treatment. These results add to evidence indicating that orbitofrontal-subcortical circuit function mediates the symptomatic expression of OCD. Specific subregions of the OFC may be differentially involved in the pathophysiology of OCD and/or its response to pharmacotherapy.

Cerebral Cortex↗
PubMed1999

Temporal assessment of quality of life of head and neck cancer patients receiving radical radiotherapy.

The study was undertaken to evaluate physical, psychological and functional aspects in quality of life (QoL) assessment prospectively in biopsy-proven head and neck cancer patients receiving radical radiotherapy. Fifty male patients were assessed using Karnofsky's Performance Status (KPS), Beck's Depression Inventory (BDI) and the Functional Living Index-Cancer (FLIC). Patient questionnaires were completed before radiotherapy, during 3-4 weeks of radiotherapy and 3 months after radiotherapy. Before the start of radiotherapy, KPS was 91 +/- 10.26, FLIC was 129.98 +/- 33.41 and BDI was 7.10 +/- 4.57. This indicated good performance and functional status with lower depression. In weeks 3-4 of radiotherapy, KPS (71.00 +/- 20.12) and FLIC (81.34 +/- 45.23) decreased, while BDI (16.56 +/- 9.01) increased, indicating impairment in QoL. Three months after radiotherapy, KPS (78.37 +/- 23.0), FLIC (119.51 +/- 43.62) and BDI (9.02 +/- 7.81) improved but were not restored to pre-treatment levels. When patients were scheduled for radical radiotherapy, maximum deterioration in QoL was seen in weeks 3-4. This is the time when maximum supportive care and psychologic counselling is required.

Activities of Daily Living↗
PubMed1999

Bone histology in patients with nephrotic syndrome and normal renal function.

BACKGROUND: The prevalence of metabolic bone disease in patients with nephrotic syndrome (NS) at normal level of renal function remains uncertain. METHODS: To address this issue, we studied 30 patients (20 men and 10 women, mean age 27.3 +/- 11.7 years) with NS who had normal renal function (mean creatinine clearance 103 +/- 4 ml/min). We evaluated their serum calcium, phosphorus, alkaline phosphatase, immunoreactive parathyroid hormone (iPTH), vitamin D metabolites, urinary calcium, and skeletal survey. The extent of bone mineralization was analyzed by histomorphometric analysis of iliac crest bone biopsy specimens in all patients. The findings on bone histology were correlated with biochemical parameters. RESULTS: The mean duration of NS was 35.5 +/- 26.9 months, with a protein excretion of 7.3 +/- 3.2 g/24 hr and a serum albumin of 2.2 +/- 0.8 g/dl. Total serum calcium was 7.8 +/- 0.8 mg/dl, whereas ionized calcium was 5.7 +/- 0.7 mg/dl, phosphorus 3.2 +/- 1.2 mg/dl, and alkaline phosphatase 149 +/- 48.6 U/liter. Serum iPTH levels were normal in all except two patients. The mean serum 25-hydroxyvitamin D [25(OH)D] level was 3.9 +/- 1.2 ng/ml (normal 15 to 30 ng/ml), whereas 1,25-dihydroxyvitamin D was 24 +/- 4.7 pg/ml (normal 16 to 65). There was an inverse correlation between serum levels of 25(OH)D and the magnitude of proteinuria (r = -0.42, P < 0.05). The mean 24-hour urinary calcium excretion was 82 +/- 21 mg/day. The skeletal survey was normal in all patients. Bone histology was normal in 33.3% of the patients, whereas 56.7% had isolated osteomalacia (OSM), and 10% had an increased bone resorption in association with defective mineralization. The severity of OSM measured by mineralization lag time correlated linearly with the duration (r = 0.94, P < 0.0001) and the amount (r = 0.97, P < 0.0001) of proteinuria. All patients with NS for more than three years had histological changes. Patients with OSM had lower 25(OH)D and serum albumin as compared with those with normal histology (P < 0.005). Bone mineralization had no significant correlation with serum iPTH, divalent ions, or vitamin D levels. CONCLUSIONS: OSM is a frequent finding in adult patients with NS, even at a normal level of renal function. Its severity correlates with the amount and duration of proteinuria.

Adolescent↗
PubMed1999

Interferon enhances the activity of the anticancer ribonuclease, onconase.

Interferons (IFN) are biologic agents involved in the antiviral response and the inhibition of tumor growth. Biochemical pathways of IFN action include the double-stranded RNA-activated oligoadenylate synthetase, RNase L, and double-stranded RNA-dependent protein kinase (PKR). Extracellular ribonucleases, especially onconase, also display antiviral and antitumor properties and involve degradation of RNA. We find that IFN increases the anticancer activity of onconase. These two agents work synergistically, and the effect is seen at the level of translation probably because of the degradation of tRNA.

Animals↗
PubMed1999

Pneumoencephalus and convulsions after ventriculoscopy: a potentially catastrophic complication.

A nine-year-old boy with hydrocephalus underwent ventriculoscopy under general anesthesia. After introduction of ventriculoscope the patient had sudden bradycardia, hypotension, and shrinkage of ipsilateral cerebral hemisphere. The ventriculostomy was abandoned. At the end of anesthesia and endotracheal extubation, the patient developed generalized convulsions. Reexploration of wound did not reveal anything significant; however, postoperative CT scan of head showed massive pneumoencephalus. The patients received elective ventilation of lungs for 24 hours and made complete recovery. The authors describe the reasons for these complications and further management.

Bradycardia↗
PubMed1999

Isolation of Desulfovibrio intestinalis sp. nov. from the hindgut' of the lower termite Mastotermes darwiniensis.

A Gram-negative, anaerobic sulfate-reducing bacterium was isolated from hindgut contents of the lower termite Mastotermes darwiniensis Froggatt (strain KMS2). Strain KMS2 is motile by a single polar flagellum. The isolate possesses desulfoviridin and catalase activity. The G+C content of its DNA is in the range of 54.5-55.5 mol% (strain KMS2). It respires hydrogen and different low molecular weight organic compounds in the presence of sulfate, thiosulfate, and sulfite, and also oxygen. The isolated strain ferments pyruvate. Fastest growth with a doubling time of 12.5 h was obtained at 37 degrees C and not at 28 degrees C, the temperature at which the termites were grown. The isolate showed a 16S rDNA sequence homology of 95.9% to Desulfovibrio desulfuricans ATCC 27774 and a DNA-DNA homology of 44.6% to D. desulfuricans Essex 6 (type strain). Based on its biochemical properties and 16S rDNA sequence, the isolate was assigned to a new species named Desulfovibrio intestinalis.

Animals↗
PubMed1999

Cellular immune response to retinal S-antigen and interphotoreceptor retinoid-binding protein fragments in Eales' disease patients.

The role of retinal antigens in Eales' disease was studied in 24 patients and an equal number of healthy controls. Lymphocyte proliferative responses were tested in vitro against native S-antigen, its uveitopathogenic peptides (peptide M and peptide G), yeast histone H3 peptide and uveitopathogenic fragment of interphotoreceptor retinoid-binding protein (IRBP; R16) to establish their role in the pathogenesis of Eales' disease. Out of 24 Eales' disease patients, 6 showed significant proliferative response against S-antigen, its uveitogenic fragments or IRBP. None among the controls showed any response to any retinal antigen used in this study. There was no statistically significant difference in the response to purified protein derivative between patients and controls. These results suggest that retinal antigens may play a role in the etiopathogenesis of Eales' disease. An extraneous agent that could result in exposure of normally sequestered uveitopathogenic antigens of the immune system, leading to an exuberant immune response in the eye may initiate the disease.

Adolescent↗
PubMed1999

Memory self-appraisal in middle-aged and older adults with the apolipoprotein E-4 allele.

OBJECTIVE: Because subjective memory complaints may indicate subtle functional brain abnormalities, the authors studied the influence of the major genetic risk for Alzheimer's disease, the apolipoprotein E-4 (APOE-4) allele, on self-reports of memory performance in middle-aged and older adults. METHOD: Subjective and objective assessments of memory performance were compared in relation to the presence or absence of the APOE-4 allele in 39 cognitively intact persons with mild memory complaints. RESULTS: Subjects with the APOE-4 allele had lower scores on objective verbal memory and on the subjective memory measure for retrospective functioning. Among the subjects in the age range where APOE-4 has its greatest influence on the risk of Alzheimer's disease (55-74 years), the APOE-4 group had lower scores on the subjective memory measure for frequency of forgetting. Moreover, the standardized difference in retrospective functioning scores between the two genetic risk groups increased when the mid-age-range group was examined rather than the whole study group. CONCLUSIONS: The APOE-4 allele is associated with increased subjective memory impairment in middle-aged and older adults. Longitudinal studies of age-related memory loss should include genetic risk and subjective memory measures as potential predictors of decline.

Adult↗
PubMed1999

Quality-of-life changes among patients with obsessive-compulsive disorder in a partial hospitalization program.

Thirty treatment-resistant patients with a primary DSA-IV diagnosis of obsessive-compulsive disorder were assessed at admission to and discharge from a partial hospitalization program to determine whether improvement in symptoms of the disorder was associated with improvements in patients' quality of life. Symptom severity was measured using the Yale-Brown Obsessive Compulsive Scale (YBOCS). Quality of life was measured using Lehman's Quality of Life (QOL) scale, which includes several objective and subjective indexes. YBOCS scores significantly improved with treatment, as did scores on the majority of the QOL subjective indexes and on the objective social, health, and activity indexes. No significant association between changes in YBOCS scores and QOL scores was found.

Adult↗
PubMed1999

Assessing blood administering practices.

The risk that a red blood cell unit will be associated with an ABO-incompatible transfusion is currently slightly greater than the aggregate risk of acquiring human immunodeficiency virus, human T-cell lymphotropic virus, hepatitis B virus, or hepatitis C virus by transfusion. Since the most common cause for ABO-incompatible transfusion is the failure of transfusionists to properly identify a patient or a blood component before a transfusion, transfusion services are encouraged to evaluate and monitor the processes of dispensing and administering blood. In addition, a proposal of the Health Care Financing Administration of the Department of Health and Human Services would require hospitals to use a data-driven quality assessment and performance improvement program that evaluates the dispensing and administering of blood and that ensures that each blood product and each intended recipient is positively identified before transfusion. The Los Angeles County+University of Southern California Medical Center assesses the blood dispensing and administering process as proposed by the Health Care Financing Administration. During the fourth quarter of 1997, 85 blood transfusions were assessed for compliance with the Los Angeles County+University of Southern California Medical Center policies and procedures: 55 transfusion episodes had no variance from institutional protocol and 30 had one or more variances. Of the transfusions with at least one variance, 16 had one or more variances involving the identification of the patient, the component, or the paperwork. The remaining 14 transfusions had one or more variances involving other criteria (nonidentification items). The most frequent variance was the failure to document vital signs during the first 15 minutes after a transfusion was started or after 50 mL of a component had been transfused. No variances in patient or blood component identification were noted in nursing units whose staff routinely performed self-assessment of blood administering practices. Based on these findings, a corrective action plan was implemented. Follow-up assessments (n = 63) were conducted after 3 months (during the second quarter of 1998). The compliance with the pretransfusion identification protocol improved from 81% to 95%. The most common reason for noncompliance continued to be a lack of checking vital signs. This report demonstrates the value of using a data-driven program that assesses blood administering practices.

Blood Transfusion↗
PubMed1999

Ventilatory functions in stone quarry workers of Rajasthan.

Ninety two stone quarry workers from nearby villages of Jodhpur town were, assessed for their lung functions which included measurement of Forced vital capacity (FVC), Forced expiratory volume in Ist second (FEV1), and Peak expiratory flow rate (PEFR). A detailed questionnaire was administered to all the workers, who were divided into group I (cutting the stone) and group II (loading and unloading the stone) depending on the nature of their Job. The presenting complaints included cough with sputum (55%), chest pain (79%), bodyache (31%) and 21% gave the history as suffering from tuberculosis. Comparison of the lung function results between two groups indicated a significant decrement of FEV1 and PEFR in group II as compared to group I workers. The observed lung functions were also found to be lower on comparison with the normative data from Rajasthan. However, no difference in observed lung function results of smokers and nonsmokers were obtained. Thus the reported lower values of lung functions independent of smoking habits, may be due to occupational stone dust exposure.

Adult↗
PubMed1998

FDG-PET predictors of response to behavioral therapy and pharmacotherapy in obsessive compulsive disorder.

In subjects with obsessive-compulsive disorder (OCD), lower pre-treatment metabolism in the right orbitofrontal cortex (OFC) and anterior cingulate gyrus (AC) has been associated with a better response to clomipramine. We sought to determine pre-treatment metabolic predictors of response to behavioral therapy (BT) vs. pharmacotherapy in subjects with OCD. To do this, [18F]fluorodeoxyglucose positron emission tomography scans of the brain were obtained in subjects with OCD before treatment with either BT or fluoxetine. A Step-Wise Variable Selection was applied to normalized pre-treatment glucose metabolic rates in the OFC, AC, and caudate by treatment response (change in Yale-Brown Obsessive-Compulsive Scale) in the larger BT group. Left OFC metabolism (normalized to the ipsilateral hemisphere) alone was selected as predicting treatment response in the BT-treated group (F = 6.07, d.f. = 1,17, P = 0.025). Correlations between normalized left OFC metabolism and treatment response revealed that higher normalized metabolism in this region was associated with greater improvement in the BT-treated group (tau = 0.35, P = 0.04), but worse outcome (tau = -0.57, P = 0.03) in the fluoxetine-treated group. These results suggest that subjects with differing patterns of metabolism preferentially respond to BT vs. medication.

Adult↗
PubMed1998

Solid state 2H-NMR studies of segmental dynamics in polymer blends.

Recent two-dimensional (2D) 2H-NMR studies on nearly ideal mixtures are reviewed. The use of selective deuterium labeling allows the unambiguous observation of the individual segmental dynamics of each component in the blend. 2D exchange spectra provide both the mean motional rates and the motional distributions, which was necessary to discriminate among the disparate explanations of blend behavior. The components exhibit very different mean mobilities and broad mobility distributions near the glass transition. The broad macroscopic glass transition in the blends is attributed to both these two kinds of dynamic heterogeneities. The individual mean motional rates are used to define distinct glass transition temperatures, T(g,i) for each species, i. The separation between the T(g,i),s of the two species increases with the content of the high-T(g) component. The widths of their individual motional distributions also increase with the content of the high-T(g) component. These two effects combine to produce the increase in both the anomalously broad glass transition and the thermorheological complexity of these blends with fraction of the high-T(g) component.

Deuterium↗
PubMed1998

Reverse transcription-polymerase chain reaction (RT-PCR) for direct detection of cucumber mosaic virus (CMV) in gladiolus.

A diagnostic method based on Reverse Transcription-Polymerase Chain Reaction (RT-PCR) was performed for detection of CMV genome directly in crude extracts of both healthy and infected gladiolus tissue using primers from the conserved sequences of CMV RNA-3. RT-PCR resulted in the amplification of 540 bp long fragment of CMV coat protein gene (CMV-CP), as expected in most of the plant parts of infected gladiolus samples. Positive signals in Southern hybridization of amplified fragments with cloned CMV-CP cDNA probe also confirmed the presence of CMV genome in gladiolus.

Animals↗
PubMed1998

Nucleotide sequence and intergeminiviral homologies of the DNA-A of papaya leaf curl geminivirus from India.

Coat protein gene, rep protein gene and intergenic region of the genome of a whitefly transmitted geminivirus (WTG) causing severe leaf curl in papaya plants were PCR amplified, cloned and sequenced. Comparison of the amino acid sequence of the putative coat protein product of papaya leaf curl virus (PLCV) with some other mono and bipartite WTGs revealed a maximum of 89.8% homology with Indian cassava mosaic virus. The genomic organization of PLCV-India is similar to other WTGs with bipartite genomes. Comparison of the coat protein N-terminal 70 amino acid sequence (and other biological features) of PLCV with other geminiviruses shows that PLCV is a distinct geminivirus from India and is related to WTGs from the old world.

Amino Acid Sequence↗
PubMed1998

Toxicity and therapeutic efficacy of amphotericin B delivered through cholesterol hemisuccinate vesicles in the treatment of experimental murine aspergillosis.

We have studied the toxicity and therapeutic efficacy of amphotericin B in cholesterol hemisuccinate vesicles (ABCV) in the treatment of invasive aspergillosis in Balb/c mice. The toxicity of amphotericin B was significantly reduced when delivered through cholesterol hemisuccinate vesicles as compared to deoxycholate suspension (AmB(DOC)) as evidenced by reduced nephrotoxicity in Balb/c mice, lower in-vitro toxicity to erythrocytes and higher maximum tolerated dose. The latter increased from 2 mg/kg wt for AmB(DOC) to 17 mg/kg wt for ABCV. The vesicles had a mean diameter of 252 nm. In order to evaluate the therapeutic efficacy of ABCV, Aspergillus fumigatus-infected mice were treated with ABCV 2, 4, 8 or 12 mg/kg or AmB(DOC) 1 mg/kg wt. The antifungal activity was highly dependent on the dosage of ABCV on the basis of survival of treated mice and cfu in lung, liver, spleen and kidney. This study found that ABCV had dose-dependent antifungal activity and therapeutic efficacy in the treatment of invasive aspergillosis in Balb/c mice.

Amphotericin B↗