Search PubMed⌕ Search

Biomedical subjects

V Agarwal

Publications and source records attributed to V Agarwal.

At least 55 records · Page 3Linked to original sources

Role of IgM & IgA rheumatoid factors in complement activation in patients with juvenile rheumatoid arthritis.

We studied the relationship between the degree of complement activation in juvenile rheumatoid arthritis (JRA) with the levels of circulating IgM and IgA rheumatoid factors (RF). Forty children with JRA and 25 matched controls were included in the study. Levels of C3d (a degradation product of complement component C3), circulating immune complexes (CICs), IgM RF and IgA RF were measured by ELISA. Levels of C3d, CICs, IgM RF and IgA RF were elevated in patients with JRA as compared to controls. Levels of C3d had a linear relationship with levels of CICs (P < 0.05) but not with levels of circulating IgM RF and IgA RF. Thus, complement activation occurs in children with JRA and is associated with raised levels of CICs but not with levels of circulating IgM and IgA RF. Circulating IgM and IgA RF have little, if any, role in complement activation observed in patients with JRA.

Adolescent↗

Langerhans cell histiocytosis.

Langerhans cell histiocytosis (LCH) is a rare disorder affecting predominantly children and manifesting as bone pains, bony swellings and lytic lesions. Involvement of vertebrae as presenting manifestation is unusual. Here we have presented three cases of LCH, two of multifocal eosinophilic granuloma (MEG) and one of Hand Schuller Christian disease (HSC). One of the patients with MEG; had vertebral involvement as the presenting manifestation.

Adult↗

Effect of esophageal and gastric distention on bronchial hyper-responsiveness in patients with bronchial asthma.

OBJECTIVE: Over-eating is said to aggravate asthma though the mechanism is still unclear. We tried to study the mechanism by causing distention in oesophagus and stomach. METHODS: Fifteen patients with nocturnal asthma were studied in a random cross-over design. The esophagus and stomach of the subjects were distended with a balloon. The effect of the distention on the airways was measured by taking forced expiratory volume one second (FEV1), forced vital capacity (FVC) and bronchial hyper-responsiveness (BHR). RESULTS: Distention of stomach caused significant reduction in FEV1 on FEV1/FVC ratio but similar distention of esophagus did not. Histamine PD20 was decreased by 0.43 (SEM 0.28) doubling dose with gastric distention. However, with oesophageal distention no significant change was observed in PD20. CONCLUSION: It can be concluded that gastric distention leads to broncho-constriction as measured by FEV1, FEV1/FVC ratio along with increase in BHR probably by inducing airway inflammation. Therefore asthmatic patients should be advised to avoid large meals.

Adolescent↗

Absolute bioavailability of moxifloxacin.

Moxifloxacin (BAY 12-8039) is an investigational 8-methoxy-fluoroquinolone with broad-spectrum gram-positive and gram-negative activity. To determine the absolute bioavailability of moxifloxacin, this open-label, randomized, crossover study compared the pharmacokinetic characteristics of a single 100-mg dose administered either orally or intravenously as a 60-minute infusion in 10 healthy male volunteers (mean age [+/- SD], 29.3+/-7.1 years; mean weight [+/- SD], 77.7+/-8.7 kg). Geometric mean values for oral/IV moxifloxacin were as follows: peak serum concentration, 1.15/1.34 mg/L, and area under the concentration-time curve over 48 hours, 9.86/10.89 mg x h/L. The geometric mean absolute bioavailability of oral moxifloxacin was 91.8%. Mean renal clearance was approximately 2.3 L/h after administration of both the single oral and IV formulations, which suggests lack of active tubular secretion of moxifloxacin. Both the oral and IV formulations were well tolerated, with 5 reported possible or probable drug-related adverse events; they included headache, nausea, and localized urticaria. In summary, a single oral dose of moxifloxacin was extensively absorbed in healthy young men. Further studies are necessary in actual patients to confirm the viability of IV to oral conversion at the same dose of moxifloxacin.

Administration, Oral↗

Cataplasm-based controlled drug delivery: development and optimization of a novel formulation.

The objective of the present study was to study the formulation variables involved in the development of a novel plasterlike preparation (cataplasm) and to optimize important formulation variables with an aim to maximize the in vitro release of the drug with minimum lag time. Cataplasm was prepared by dispersing a model drug (ibuprofen), humectant (glycerol), adhesive (Indopol H100), polymer (Carbopol C934P) with other formulation ingredients in a beaker with an open-blade impeller. The paste was cast on a nonocclusive backing membrane and dried overnight. The diffusion of the model drug was studied across a cellulosic membrane using Franz's diffusion cells. The amounts of three formulation variables, carbopol (X1), glycerol (X2), and indopol (X3) were studied at three levels, and a face-centered cubic design was used to maximize the flux. An optimization procedure for maximum flux and minimum lag time predicted a flux of 97.22 mcg/cm2/hr at X1 (2% w/w), X2 (11.75% w/w), and X3 (6%, w/w). An experimental patch prepared with the above concentrations yielded a flux of 90.7 mcg/cm2/hr.

Acrylic Resins↗

Design, development, and biopharmaceutical properties of buccoadhesive compacts of pentazocine.

Buccoadhesive compacts (BCs) of pentazocine (PZ) were prepared by the direct compression method using polymers like carbopol 974P (CP 974P) and hydroxypropyl methylcellulose (HPMC K4M) in ratios of 1:0 (batch B1), 1:1 (B2), 1:2 (B3), 1:4 (B4), and 0:1 (B5). The compacts were evaluated for thickness uniformity, weight variation, drug content uniformity, and swelling index. Swelling was increased with an increase in HPMC K4M content in the compacts. An in vitro assembly was developed to measure and compare the bioadhesive strength of compacts. The maximum bioadhesive strength was observed in compacts formulated with a combination of CP 974P and HPMC K4M. The compacts were evaluated in vitro for 24 hr in pH 6.6 phosphate buffer using a standardized dissolution apparatus. The data were evaluated by a simple power equation (Mt/M infinity = Ktn); it was observed that all the compacts followed non-Fickian release kinetics. Some of the buccoadhesive compacts were evaluated in vivo in rabbits. The compacts gave controlled blood level profiles with a twofold to threefold increase in area-under-the-curve (AUC) values in comparison to oral administration of aqueous drug solution.

Adhesives↗

Molecular characterization of an Indian isolate of Japanese encephalitis virus that shows an extended lag phase during growth.

The biological properties of an Indian isolate (GP78) of Japanese encephalitis virus (JEV) were characterized in tissue-cultured cells and mice and these were compared with the JaOArS982 strain from Japan. The GP78 strain had a markedly extended lag phase during its growth in porcine stable kidney (PS) cells. There were no obvious defects in the penetration of GP78 into PS cells. However, viral RNA and protein synthesis were significantly delayed in GP78-infected PS cells. Fusion-from-within assays carried out in C6/36 cells indicated that GP78 was less fusogenic than the JaOArS982 strain of JEV. Moreover, maximum fusion in GP78-infected cells occurred at pH 5.5, whereas JaOArS982-infected cells showed maximum fusion at pH 6.0. These results suggested that there may be a lesion in the virus-cell fusion process. The GP78 strain also showed delayed growth in brains of 1-week-old BALB/c mice. Although JEV GP78 was as virulent as the JaOArS982 strain in these mice, the appearance of clinical symptoms of JEV infection was delayed by a day in mice infected with the GP78 strain and these animals showed an increased average survival time. Comparison of the nucleotide sequences of the GP78 and the JaOArS982 strains of JEV identified a number of amino acid substitutions in structural proteins. Of these, a Thr --> Met substitution at residue 76 of the envelope protein is predicted to be causally associated with the altered biology of the GP78 strain during growth.

Amino Acid Sequence↗

Pharmacokinetics of a once-daily oral dose of moxifloxacin (Bay 12-8039), a new enantiomerically pure 8-methoxy quinolone.

The pharmacokinetics, safety, and tolerability of oral moxifloxacin, a new 8-methoxy quinolone, were assessed in a randomized, double-blind, placebo-controlled study in which healthy male and female volunteers received either 400 mg of moxifloxacin once daily (n = 10) or a placebo once daily (n = 5) for 10 days. Plasma moxifloxacin concentrations on days 1 and 10 were measured by high-performance liquid chromatography and fluorometric detection. Standard pharmacokinetic parameters were estimated by noncompartmental methods. Natural logarithmic estimates for each pharmacokinetic variable of each subject were analyzed by a two-way analysis of variance. Hematology, blood chemistry, vital signs, and adverse events were monitored, and electrocardiograms (ECG) were performed. Plasma moxifloxacin concentrations of predicted therapeutic relevance were achieved in this study. For day 1, the mean maximum concentration of drug in serum (C(max)) and the area under the concentration-time curve from 0 to 24 h (AUC(0-24)) were 3. 4 mg/liter and 30.2 mg. h/liter, respectively. Corresponding means on day 10 were 4.5 mg/liter and 48 mg. h/liter, respectively. On day 10, the mean elimination half-life was approximately 12 h. Plasma moxifloxacin concentrations exceeded the MIC for Streptococcus pneumoniae throughout the 24-h dosing period. The day 1 and day 10 mean AUC/MIC ratios were 121 and 192, respectively, and the mean C(max)/MIC ratios were 13 and 18, respectively. Moxifloxacin was well tolerated; no clinically relevant changes in the standard laboratory tests, vital signs, or ECG were observed. Pharmacokinetic parameters demonstrated linearity, and estimates of pharmacokinetic/pharmacodynamic ratios (AUC/MIC and C(max)/MIC) indicate that the regimen of 400-mg once daily should be effective for treating a variety of infections. Moxifloxacin was found to be safe and well tolerated in healthy volunteers when it was given as a single daily 400-mg dose for 10 days.

Adolescent↗

Recent trends in drug delivery systems: intranasal drug delivery.

Nasal route of drug delivery is commonly known for treatment of local ailments like-cold, cough, rhinitis etc. Recently, efforts have been made to deliver various drugs, specially peptides and proteins, through nasal route for systemic use; utilizing the principles and concepts of rate controlled drug delivery and various polymers and absorption promoters. Considering the large number of problems associated with oral, parenteral, rectal and other routes of drug administration and gradual increase in interest of pharmaceutical scientists towards exploring the possibilities of intranasal delivery of various drugs, this article aims at giving an insight into nasal cavity, consideration of factors affecting and strategies to improve drug absorption through nasal route, pharmaceutical dosage forms and delivery systems with examples of some peptides for intra nasal delivery, its advantages and limitations.

Administration, Intranasal↗

Intracranial Hodgkin's disease in two patients with familial Hodgkin's disease.

Intracranial Hodgkin's disease is very rare and is often a terminal event. The case of a 33-year-old man who relapsed in the anterior pituitary gland without other evidence of disease 6 months after extended field radiation therapy for Stage IIA Hodgkin's disease is presented. He remains well with no evidence of disease five years after surgery and chemotherapy for intracranial relapse. The case of a 16-year-old boy with a dural relapse of Hodgkin's disease associated with positive cerebrospinal fluid cytology is also presented. These two patients are members of different families each with multiple cases of Hodgkin's disease. Central nervous system involvement with Hodgkin's disease may be more frequent in familial Hodgkin's disease in which immune deficiency is common.

Adolescent↗

Spectrofluorometric estimation of aspirin and dipyridamole in pure admixtures and in dosage forms.

Aspirin and dipyridamole in pure admixtures and in dosage forms have been estimated by spectrofluorometry. Aspirin (2-12 mcg ml-1) was estimated in 1% v/v glacial acetic acid in chloroform using 246 and 345 nm for excitation and emission respectively. Dipyridamole (2-12 mcg ml-1) has been estimated in chloroform using 420 nm for excitation and 475 nm for emission. The non-interference of the excipients as well as the drugs in the estimation of each other, as evidenced by the results, indicate that this method may be used for the routine estimation of aspirin and dipyridamole in tablet preparations.

Aspirin↗

Examination stress: changes in serum cholesterol, triglycerides and total lipids.

Serum cholesterol, triglycerides and total lipids were estimated in twelve students exposed to varying degree of examination stress. Serum cholesterol and triglycerides exhibited a rise proportional to degree of examination stress whereas total lipids exhibited an initial rise followed by a fall. Values of all these parameters attained control level when the stress was over. The rise in serum cholesterol and triglycerides seems to be due to stress induced changes in hormonal levels and peripheral lipolysis respectively.

Adult↗

Extended spectrum beta-lactamase mediated resistance to third generation cephalosporins in Klebsiella pneumoniae in Nagpur, central India.

Out of 66 clinical isolates of Klebsiella pneumoniae, 17 showed resistance or decreased susceptibility to third generation cephalosporins (17 to cefotaxime, 16 to ceftriaxone, and 9 to ceftazidime) while the remaining 49 were sensitive by the disc diffusion method. The minimum inhibitory concentrations (MICs) of the third generation cephalosporins (3GC) for the strains ranged from 2-128 micrograms/ml by agar dilution method. Their sensitive phenotypes had zone diameters smaller (mean difference 3. 1 mm for ceftriaxone, and 6.5 mm for ceftazidime), and MICs > 10 fold higher than the corresponding values in the fully sensitive isolates. Resistance to cefotaxime was transferred to recipient Escherichia coli K12 strain in 15 isolates. All the resistant isolates were sensitive to imipenem but were variably sensitive to aminoglycosides, and quinolones. In all 17 resistant isolates extended spectrum beta-lactamase (ES beta L) was detected. The sensitivity testing systems may fail to recognise the potential ES beta L mediated resistance to 3GC. Hence ES beta L detection should be routinely undertaken.

Cephalosporin Resistance↗

Endocrine disorders associated with inappropriately high aromatase expression.

Aromatase P450 (P450arom) is responsible for conversion of C19 steroids to estrogens in a number of human tissues, such as the placenta, gonads, adipose tissue, skin and the brain. Aromatase expression in human tissues is regulated by use of alternative promoters in the placenta (promoter I.1), adipose tissue (promoters I.4, I.3 and II) and gonads (promoter II). Aromatase expression is absent in the disease-free adult liver, adrenal and uterine tissues. Excessive or inappropriate aromatase expression in adipose fibroblasts and endometriosis-derived stromal cells, as well as in testicular, hepatic, adrenal and uterine tumors, is associated with abnormally high circulating estrogen levels and/or with increased local estrogen concentrations in these tissues. Whether systemically delivered or locally produced, elevated estrogen levels will in turn promote the growth of hormone-responsive tissues. We recently studied aromatase expression in testicular tumor and adipose tissue samples from prepubertal boys with gynecomastia, in hepatocellular cancer and adrenocortical tumor samples from adult men with gynecomastia, in breast adipose tissue samples proximal to breast tumors, and in endometrial cancer, leiomyoma and endometriosis tissues. Excessive aromatase activity and P450arom transcript levels were found in these tissue samples or in cultured cells derived from these tissues. In these neoplastic or non-neoplastic tissues or cells, the regulation of aromatase expression was studied in terms of alternative promoter use, both in vivo and in response to various hormonal stimuli. Our results were suggestive of a common metabolic abnormality associated with activation of a cyclic AMP-dependent signalling pathway that gives rise to transcriptional transactivation of aromatase expression via promoters I.3 and II in all of the above tissues. This article describes the common pathophysiological and molecular features of excessive aromatase expression in these disease states.

Adolescent↗