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V Agarwal

Publications and source records attributed to V Agarwal.

At least 19 recordsLinked to original sources
PubMed2004

Photon BLOCH oscillations in porous silicon optical superlattices.

We report the first observation of oscillations of the electromagnetic field in an optical superlattice based on porous silicon. These oscillations are an optical equivalent of well-known electronic Bloch oscillations in crystals. Elementary cells of our structure are composed by microcavities whose coupling gives rise to the extended collective modes forming optical minigaps and minibands. By varying thicknesses of the cavities along the structure axis, we have created an effective electric field for photons. A very high quality factor of the confined optical state of the Wannier-Stark ladder may allow lasing in porous silicon-based superlattices.

Journal Article↗
PubMed2003

Autoimmune hemolytic anemia associated with benign ovarian cyst: a case report and review of literature.

A 28-years-old female presented with severe autoimmune hemolytic anemia (AIHA), warm antibody mediated, and right side tubo-ovarian (TO) mass. There was sub-optimal response to immunosuppressive therapy (IST). Eight months later she underwent ovarian cystectomy which resulted in complete remission of AIHA without the need for IST. Pathological examination of the TO mass revealed benign ovarian cyst. Our case highlights the need to search for ovarian cyst/mass in females presenting with AIHA. Since immunosuppressive therapy is usually ineffectual in AIHA associated with ovarian cyst, it may be appropriate to contemplate surgery before embarking on IST in such cases.

Adult↗
PubMed2003

A simple HPLC method for the simultaneous analysis of insulin and ovomucoid.

An analytical HPLC method is reported for the simultaneous determination of insulin and its enzyme inhibitor, chicken ovomucoid. Verapamil was used as an internal standard. The elution was achieved using a gradient technique (10-15% B for 4 min, 15-35% B from 5th to 11th min and 35-10% B from 12th to 22nd min). The mobile phase used was 0.05% v/v trifluoroacetic acid (TFA) in water and 0.05% v/v TFA in acetonitrile with a flow rate of 1.2 ml/min. The analytes were detected at 210 nm after resolution using a reversed phase C-18 column. Insulin, ovomucoid and verapamil (IS) were eluted at 11.9, 14.2, and 18 min, respectively, free from any interfering endogenous peaks during a run time of 22 min. Linear relationships were observed between the detector response and the concentrations of the analytes (0.05-1 I.U/ml for insulin (r2 = 0.9975) and 5-100 microg/ml for the chicken ovomucoid (r2 = 0.9993)). The assay was found to be highly selective and sensitive due to the absence of any interfering peaks. The lower C.V and % error values of the assay indicates that the assay could accurately and precisely quantitate both insulin and ovomucoid in the examined concentration range. This method can be used for the simultaneous quantitation of insulin and chicken ovomucoid.

Animals↗
PubMed2002

The effect of hemodialysis on the transport of sodium in erythrocytes from chronic renal failure patients maintained on hemodialysis.

Studies were undertaken to evaluate the modulatory effect of maintenance hemodialysis on ouabain sensitive (OS) and ouabain insensitive (OIS) 22Na(+) uptake in erythrocytes (E) of 8 chronic renal failure patients of both sexes. Following the receipt of informed consent, the blood samples were obtained just before and after Dialysis. The % 22Na(+) uptake of the total 22Na(+) present in the assay media was determined in the purified E just before and after Dialysis. The assay medium was composed of 100 mM NaCl, 5 mM KCl, 10 mM trisbase, 10 mM MOPS, 10 mM D-glucose and 60 mM sucrose, pH 7.4 with and without ouabain. Five different concentrations of E, ranging from 0.75 to 2.00 x 10(9)/mL were used for this study. We observed a linear relationship between the 22Na(+) uptake and E concentrations in both of the assay systems (OS and OIS). The mean total 22Na(+) uptake per 6.5 x 10(9) E/mL in OS and OIS before and after hemodialysis were 3.28 +/- 0.4 (OS) and 3.26 +/- 0.42 (OIS), and 3.42 +/- 0.54 (OS) and 3.42 +/- 0.68 (OIS) respectively. The relative % differences between pre- and post-Dialysis were 4 and 5%, which were statistically not significant. From this study, we conclude that hemodialysis does not affect E membrane properties influencing 22Na(+) transport.

Aged↗
PubMed2002

Thrombocytopenia as the presenting manifestation of sarcoidosis.

Sarcoidosis is a chronic granulomatous disorder characterized by multisystem involvement, however, symptomatic thrombocytopenia as a presenting manifestation is rare. Here we are reporting a case of sarcoidosis presenting with splenomegaly and severe immune thrombocytopenia as a presenting manifestation.

Adrenal Cortex Hormones↗
PubMed2002

Does cyclophosphamide benefit relapsing thrombotic thrombocytopenic purpura?

Thrombotic thrombocytopenic purpura (TTP) is a rare disease. A high index of suspicion is required for early diagnosis and treatment. It can present in acute as well as chronic forms. Cyclophosphamide has been reported to be beneficial in relapsing TTP. Herein a case of acute TTP evolving into relapsing phase of the disease is presented. Cyclophosphamide in our case achieved partial remission without the need for plasma exchange therapy. The rationale of cyclophosphamide in management of relapsing TTP is discussed.

Adult↗
PubMed2001

Polymethyacrylate based microparticulates of insulin for oral delivery: preparation and in vitro dissolution stability in the presence of enzyme inhibitors.

The purpose of this investigation was to (a) evaluate the coprecipitation technique for preparing microparticulates of insulin, (b) study the effect of variables such as addition of salts in the precipitating medium and ratio of polymeric solution to volume of precipitating medium on the dissolution and encapsulation efficiency of insulin microparticulates, and (c) evaluate the in-vitro enzymatic dissolution stability of insulin microparticulates in the presence of chicken ovomucoid (CkOVM) and duck ovomucoid (DkOVM) as inhibitors. Insulin dissolved in 0.01 N HCl was mixed with alcohol USP to get a final concentration of 32% v/v. Eudragit L100, a representative polymethyacrylate polymer, was then dissolved in this solution which was transferred to a beaker containing cold water with homogenization to obtain microparticulates. Dissolution studies were carried out in pH 6.8 phosphate buffer using a 100-ml conversion kit in a standard dissolution assembly. Dissolution stability of microparticulates was evaluated in the presence of 0.5 microM trypsin and 0.l microM chymotrypsin at various ratios of CkOVM and DkOVM. The results indicated that insulin microparticulates could be prepared using the coprecipitation technique with high encapsulation efficiency by proper selection of experimental conditions and amount of polymer. Presence of salts in the precipitating medium decreased the dissolution of insulin from the microparticulates. As the ratio of precipitating medium with respect to the polymeric solution was increased, the encapsulation efficiency increased. In dissolution stability experiments, insulin was not detected in the presence of enzymes alone. When CkOVM and DkOVM were incorporated, the stability of insulin increased significantly in a concentration dependent fashion.

Administration, Oral↗
PubMed2001

Neurocysticercosis presenting as psychiatric illness.

Neurocysticercosis is a common neuroparasitosis. Presentation with psychiatric symptoms is uncommon in neurocysticercosis. The present paper describes a patient who presented with mutism, neglect of personal care and incontinence in a psychiatric setting and investigations revealed diagnosis of neurocysticercosis. The case report highlights the possible misdiagnoses of a case of neurocysticercosis as psychiatric illness and mutism as an uncommon presentation of neurocysticercosis.

Adolescent↗
PubMed2001

Splenic tuberculosis presenting as hypersplenism.

A 9-year-old girl with a 5-6-month history of abdominal distension and fever was found to have massive splenomegaly with features of hypersplenism. Apart from a strongly positive Mantoux test, all investigations for massive splenomegaly proved negative. Splenectomy was carried out and histopathological examination of the spleen revealed granulomatous lesions suggestive of tuberculosis. The child improved after splenectomy and anti-tuberculous therapy and is doing well on follow-up. Splenic tuberculosis should be considered as an unusual cause of massive splenomegaly and hypersplenism.

Child↗
PubMed2001

Bacterial vaginosis in early pregnancy and adverse pregnancy outcome.

OBJECTIVE: To assess the prevalence of bacterial vaginosis (BV) in asymptomatic pregnant women and its association with preterm birth (PTB) and premature rupture of membranes (PROM). METHODS: In a cohort study 1,006 pregnant women between 16-28 weeks' gestation were screened for BV (Nugent's criteria) and for lower genital tract infection. Women were followed to confirm pregnancy outcome. Data were analyzed using STATA software. Univariate and multivariate methods were used to investigate the association between bacterial vaginosis and adverse pregnancy outcome. RESULTS: Prevalence of BV was 11.53%. Baseline characteristics were similar for both groups, 6.8% women were lost to follow-up. Incidence of PTB was higher in BV positive women compared to BV negative women (p = 0.001). On multiple logistic regression (MLR), BV was associated with an increased risk of PTB (p = 0.001) and PROM (p = 0.001), other correlates being previous PTB (p = 0.003) and the presence of enteropharyangeal organisms in vagina (p = 0.03). BV accounted for 82.53% of the attributable risk for PTB. CONCLUSION: Presence of BV in early pregnancy is associated with an increased risk of PTB and PROM. Multicentric interventional study is recommended.

Adult↗
PubMed2001

Help seeking behaviour of psychiatric patients before seeking care at a mental hospital.

BACKGROUND: A wide range of professionals including psychiatrists, psychologists, general physicians, faith-healers and religious healers cater to the needs of mentally ill patients. Psychiatric facilities are available at general hospitals, office based practice and mental hospitals. Psychiatrists are preferred the least due to stigma. The present work reports on treatment options used by a group of psychiatric patients before visiting a mental hospital. AIM: To study the help seeking behaviour of patients visiting a mental hospital. METHOD: Patients attending psychiatric outpatient service at a mental hospital were asked specifically about various treatment facilities utilized by them before coming to the hospital and the reasons thereof. RESULTS: A wide range of services was used by the subjects varying from professional care to faith healers. Trust, easy availability and accessibility, recommendations by the significant others and belief in supernatural causation of illness were the important reasons for choosing a particular facility. Thus sociocultural factors appeared to influence the help seeking behaviour. CONCLUSION: A substantial number of patients suffering from severe mental disorders seek non-professional care. There is a need of studies in community to assess the help seeking behaviour of psychiatric patients and factors associated with it.

Adolescent↗
PubMed2001

Pharmacokinetics, safety, and tolerability of BAY 12-9566 and nonsteroidal anti-inflammatory agents (naproxen, ibuprofen) during coadministration in patients with osteoarthritis.

The pharmacokinetic interactions between BAY 12-9566 and two nonsteroidal anti-inflammatory drugs (NSAIDs), naproxen and ibuprofen, were investigated in osteoarthritis (OA) patients. The study comprised six groups: two NSAID groups with three levels of treatment (BAY 12-9566 400 mg, BAY 12-9566 100 mg, and placebo). Plasma pharmacokinetic parameters (AUC(0-tau), Cmax, and tmax) were determined for each treatment group following 5 days of NSAID administration, 14 days of BAY 12-9566 administration, and 14 days of concurrent NSAID and BAY 12-9566 administration. For most conditions, the total plasma drug concentrations of both NSAID and BAY 12-9566 were diminished by coadministration; total plasma BAY 12-9566 was not affected by ibuprofen treatment. Importantly, the free drug concentrations were largely unaffected by coadministration. Most side effects were mild or moderate in intensity, and all events, with the exception of headache, were reported in both NSAID groups and in both placebo and BAY 12-9566 groups.

Adult↗
PubMed2001

Transport studies of insulin across rat jejunum in the presence of chicken and duck ovomucoids.

Our aim was to evaluate the transport of insulin across rat jejunum in the presence of ovomucoids and to assess the effect of ovomucoids on intestinal tissue by studying the permeation of a lipophilic and a hydrophilic marker. Rat jejunal segments were mounted in a side-by-side diffusion chamber filled with Krebs bicarbonate buffer, bubbled with 95% O2/5% CO2 at a fixed flow rate and maintained at 37 degrees C. The permeation of insulin, a lipophilic marker ([7- 3H] testosterone) and a hydrophilic marker (D-[1- 14C] mannitol) was evaluated in the presence of 0.5-1.5 microM duck ovomucoid (DkOVM) or chicken ovomucoid (CkOVM). For stability and permeation of insulin in the presence of alpha-chymotrypsin, an enzyme-to-inhibitor ratio of 1:1 and 1:2 was used. In the absence of alpha-chymotrypsin, the permeability coefficient (Papp) of insulin at pH 7.4 was 0.922+/- 0.168 x 10(-7) cm s(-1), which decreased with increasing concentrations of DkOVM or CkOVM. Conversely, the permeation of the hydrophilic and lipophilic marker increased with increasing concentrations of CkOVM and DkOVM. In stability studies, the percentage of drug remaining was found to be 2-fold higher at the 1:2 ratio than with the 1:1 ratio of enzyme to inhibitor. This was in agreement with the 2-fold increase in flux values of insulin in the presence of alpha-chymotrypsin and DkOVM at the 1:2 ratio of enzyme to inhibitor. The decrease in permeation of insulin in ovomucoids was unexpected. Marker transport studies indicated that ovomucoids have the potential to modulate transcellular and paracellular permeability. The flux enhancement of insulin in the presence of alpha-chymotrypsin and DkOVM is encouraging. The use of ovomucoids offers potential to enhance oral delivery of insulin and warrants further investigation.

Animals↗
PubMed2001

Double-blind, placebo-controlled trial of clonidine in hyperactive children with mental retardation.

A 12-week, double-blind, randomized, placebo-controlled trial of oral clonidine in three fixed doses (4, 6, and 8 mcg/kg/day) using a crossover design was conducted with 10 children who had hyperkinetic disorder (mean age 7.6 years +/-.54). All had comorbid mental retardation. Both parents' ratings on the Parent Symptom Questionnaire and clinicians' ratings on the Hillside Behaviour Rating Scale showed a marked dose-related response to clonidine in hyperactivity, impulsivity, and inattention. Drowsiness was a common side effect of clonidine. It wore off by the 2nd to 4th week in most cases. Thus, clonidine is a safe and effective medication in young hyperkinetic children with comorbid mental retardation.

Adolescent↗
PubMed2001

Effect of food on the pharmacokinetics of a single oral dose of moxifloxacin 400mg in healthy male volunteers.

OBJECTIVE: To investigate the effects of concomitant food intake on the pharmacokinetics of a single oral dose of moxifloxacin 400mg. DESIGN: This was a randomised 2-way nonblinded crossover study in healthy volunteers. PARTICIPANTS: 18 young, healthy, male volunteers were enrolled in the study, of whom 16 were considered evaluable for the pharmacokinetic analysis. METHODS: Moxifloxacin was given under 2 conditions separated by a 1-week washout period: fasted and fed (immediately after a standardised high fat breakfast). Concentrations of moxifloxacin in serum were determined by a validated high performance liquid chromatography procedure with fluorescence detection. OUTCOME MEASURES: Pharmacokinetic parameters such as maximum concentration (Cmax), time to reach Cmax (tmax), area under the concentration-time curve from zero to 48 hours (AUC48h), AUC from zero extrapolated to infinity (AUCinfinity) and elimination half-life (t1/2z) were estimated using noncompartmental methods. The natural logarithms of AUC and Cmax were analysed using analysis of variance. Bioequivalence of the 2 treatments was determined at the 5% significance level with the two 1-sided tests procedure and limits of 80% and 125% for AUC and 70 to 143% for Cmax. RESULTS: The mean serum concentration versus time profiles were similar between the 2 treatments. The geometric mean AUCinfinity values under fed and fasted conditions were almost identical, 37.7 versus 38.5 mg/L x h, respectively [90% confidence interval (CI) of the ratio of fed versus fasted based on geometric least-square means was 0.95, 1.00]. Geometric mean Cmax values were slightly reduced by food, 2.5 versus 2.8 mg/L, respectively (90% CI of fed versus fasted based on geometric least-square means was 0.78, 0.98). The absorption of moxifloxacin seems to be mildly delayed because of the effect of food; the median tmax values were 1.0 and 2.5 hours for fasted and fed conditions, respectively. The single oral dose of moxifloxacin 400mg was well tolerated when taken with and without food.

Administration, Oral↗