PubMed Health⌕ Search

Biomedical subjects

R B Patel

Publications and source records attributed to R B Patel.

At least 19 recordsLinked to original sources

Airway function and markers of airway inflammation in patients with treated hypothyroidism.

BACKGROUND: There is increasing evidence of an association between organ specific autoimmune diseases, particularly autoimmune thyroid disease and respiratory morbidity. A study was undertaken to determine whether patients with autoimmune thyroid disease have objective evidence of airway inflammation and dysfunction. METHODS: Twenty six non-smoking women with treated hypothyroidism and 19 non-smoking controls completed a symptom questionnaire and underwent full lung function tests, capsaicin cough reflex sensitivity measurement, methacholine challenge test, and sputum induction over two visits. RESULTS: Symptoms of cough (p = 0.01), dyspnoea (p = 0.01), sputum production (p = 0.004), and wheeze (p = 0.04) were reported more commonly in patients than controls. Patients with hypothyroidism had heightened cough reflex sensitivity compared with controls (geometric mean concentration of capsaicin causing five coughs: 40 v 108 mmol/l; mean difference 1.4 doubling doses; 95% confidence interval of difference 0.4 to 2.5; p = 0.008) and a significantly higher proportion of patients had airway hyperresponsiveness (methacholine provocative concentration (PC(20)) <8 mg/ml: 38% v 0%; p = 0.016). Patients with hypothyroidism also had a significantly higher induced sputum total neutrophil cell count (p = 0.01), total lymphocyte count (p = 0.02), and sputum supernatant interleukin-8 concentrations (p = 0.048). CONCLUSION: Patients with treated hypothyroidism report more respiratory symptoms and have objective evidence of airway dysfunction and inflammation.

Biomarkers↗

Chronic tonsillar enlargement and cough: preliminary evidence of a novel and treatable cause of chronic cough.

Tonsillar enlargement is sometimes seen in patients with otherwise unexplained chronic cough although its significance is unclear. In this study, the authors set out to test the hypothesis that cough symptoms and cough reflex sensitivity will improve after tonsillectomy in patients with otherwise unexplained chronic cough and enlarged tonsils. Eight consecutive patients with unexplained chronic cough and enlarged tonsils were recruited from 236 patients seen in a cough clinic between 2000 and 2001. Six patients with enlarged tonsils and no cough who were undergoing tonsillectomy for other reasons were recruited as a control group. All patients rated cough severity on a cough visual analogue score (0-100 mm) and had capsaicin cough reflex sensitivity measurement twice before and again 3 months after tonsillectomy. Patients with a chronic cough had heightened cough reflex sensitivity compared with the control group at baseline. There was a significant improvement in mean cough visual analogue score 3 months after tonsillectomy in patients with chronic cough (mean difference 30 mm; 95% confidence interval of difference 8-51 mm). The geometric mean concentration of capsaicin required to cause five coughs increased from 4 to 207 micromol L(-1) after tonsillectomy in patients with chronic cough (mean difference from baseline 5.6 doubling concentrations; 95% confidence interval of difference 3.1-8.2). There was no change in cough reflex sensitivity in control patients after tonsillectomy. These preliminary findings suggest for the first time a possible role for tonsillectomy in patients with enlarged tonsils in whom other causes of cough have been ruled out.

Administration, Inhalation↗

Spontaneous cerebrospinal fluid leakage and middle ear encephalocele in seven patients.

Isolated cases of spontaneous cerebrospinal fluid (CSF) leakage with and without middle ear encephalocele have been reported. These leaks are usually accompanied by episodes of recurrent meningitis, hearing loss, or chronic headache. In this article, we report seven new cases of spontaneous CSF leakage. Six of these patients had conductive hearing loss and serous otitis media, and three had recurrent meningitis. Prior to a definitive diagnosis, six patients had received myringotomy tubes, which produced profuse clear otorrhea. Three patients had positive beta-2 transferrin assays. Computed tomography and magnetic resonance imaging confirmed a defect in the temporal bone tegmen. A combined transmastoid and middle fossa surgical approach with a three-layer closure was used to repair the tegmen defect. All patients had a lumbar drain placed prior to surgery. In addition to describing the seven new cases, we review the history of CSF leakage and discuss diagnostic methods, surgical findings, and our recommendations for management.

Adult↗

Leuprolide acetate in the management of cesarean scar endometriosis.

BACKGROUND: Progestin or estrogen-progestin combination therapy has not proven useful in the treatment of endometriosis of the abdominal scar after cesarean delivery. We report our experience in managing this condition with a gonadotropin agonist. CASE: A 22-year-old black woman with a history of two previous cesareans developed endometriosis of the abdominal scar. The extent of the lesion was estimated by computed tomographic (CT) scan, and a 6-month preoperative course of leuprolide acetate was administered. The patient exhibited prompt symptomatic response to the gonadotropin agonist, but the physical examination and CT scan findings were unchanged. Pathologic examination after surgical removal of the lesion confirmed the clinical diagnosis. CONCLUSION: Leuprolide acetate administered to a patient with cesarean scar endometriosis was associated with an improvement in symptoms, but there was no change in lesion size.

Adult↗

Pharmacokinetics of gentamicin in rabbits pretreated with nonsteroidal anti-inflammatory drugs: an interaction study.

Interaction between nonsteroidal anti-inflammatory drugs (NSAIDs) and other drugs occurs relatively frequently because of the wide use of NSAIDs. Such interactions with drugs of narrow therapeutic index used in serious disease states may lead to toxicity. Gentamicin toxicity is based on its concentration in serum, and any alteration in pharmacokinetic parameters may lead to gentamicin accumulation in the body and subsequently to severe nephrotoxicity and ototoxicity. To test this hypothesis, the effect of pretreatment with NSAIDs on gentamicin pharmacokinetics was examined in rabbit. Gentamicin sulfate (5 mg/kg) was administered to rabbits pretreated with aspirin (300 mg/kg), ketorolac tromethamine (3 mg/kg), ibuprofen (20 mg/kg), and piroxicam (2 mg/kg) twice a day for 1 week. The pretreatment with NSAIDs had significant effects on the body clearance and maximum concentration. Aspirin, piroxicam and ketorolac tromethamine pretreatment had significant effects on the area under the curve of gentamicin versus time. Aspirin and ketorolac tromethamine pretreatment had significant effects on the half-life of gentamicin. Aspirin had a significant effect on the volume of distribution of gentamicin. These results suggest that pretreatment with NSAIDs alters the pharmacokinetics of gentamicin and leads to accumulation inside the body, which could result in toxicity.

Animals↗

Leuprolide acetate depot for the treatment of uterine leiomyomas. Changes in bone density, uterine volume and uterine vascular resistive index.

This study measured the changes in uterine volume, uterine vascular resistive index and lumbar vertebral bone density before and after a six-month course of leuprolide acetate depot in women with uterine leiomyomas. All nine patients studied were black. The high baseline bone density of black women may provide a greater scope for the use of gonadotropin agonists as compared to women in the general population. A significant reduction in uterine volume was achieved in the patients with leuprolide therapy. Uterine vascular resistive indices were not altered consistently following leuprolide therapy in women with leiomyomas.

Adult↗

Significance of MRI changes after surgery of the skull base.

Magnetic resonance (MR) imaging is commonly used in the followup of patients who have undergone surgical removal of tumors from the cranial base to assess the possibility of tumor recurrence, persistence, or surgical complications. Interpretations of this study must be cautious because postoperative enhanced signals are encountered frequently. Although technological improvements continue to enhance the usefulness of MR images for followup, problems remain in differentiating between fibrotic, reconstructive changes, and tumor recurrence. In this study, the hospital records and MR findings of 215 patients who had undergone skull base surgery were reviewed. The study was prompted by negative operative exploration in three patients in whom postoperative MR images strongly suggested tumor recurrence. One-year follow-up images were available in 174 patients. Of these, 94% showed signal enhancement on the 1-year follow-up study. Progressive changes were observed in 14% of patients. The correlation of preoperative MR findings and surgery, with regard to dural involvement, vascular involvement, cranial nerve infiltration, and extent of intracranial infiltration, was analyzed in 28 patients. Methods to facilitate the detection of tumor recurrence using MR images are reviewed.

Adult↗

Acute urinary retention due to a free-standing broad ligament leiomyoma.

A 38-year-old woman who had used oral contraceptives continuously since age 22 presented with acute urinary retention. Physical examination revealed a bladder outlet obstruction due to a large paravaginal/broad ligament mass. Magnetic resonance imaging (MRI) demonstrated that the mass was separate from the uterus which was confirmed at surgery when an isolated free-standing leiomyoma was removed.

Adult↗

Detection and determination of free and plasma protein-bound astemizole by thin-layer chromatography: a useful technique for bioavailability studies.

A thin-layer chromatographic (TLC) procedure has been developed for the determination of astemizole in plasma as the free and as protein-bound substance. The detection and quantification were performed without using internal standards. In earlier described methods for the estimation of astemizole by high-performance liquid chromatography and radioimmunoassay, only free levels in plasma were quantified, at 3.3% of the total astemizole, with the remaining 96.7% bound to plasma protein and tissue. Our method employs proteolysis of plasma proteins by incubating plasma for 2 h in pepsin. After proteolysis the astemizole is extracted, and a known amount of the extract is spotted on precoated silica gel F 254 plates. Astemizole was quantified using a Shimadzu CS-930 dual-wavelength TLC scanner. The method provides a direct estimate of total astemizole present in the plasma.

Animals↗

Preparation and evaluation of 99mTc-t-butylisonitrile (99mTc-TBI) for myocardial imaging: a kit for hospital radiopharmacy.

A previous method was modified to obtain [99mTc(TBI)6]+ by reacting Zn(TBI)2Br2 directly with 99mTcO4- in the presence of Sn2+ ions. [Cu(TBI)4]Cl was next used as a source of TBI. On reaction with 99mTcO4- and Sn2+ ions for 3 min at 100 degrees C, [99mTc(TBI)6]+ product of radiochemical purity greater than 90% and yield greater than 70% was obtained. Data of biodistribution in rats (2-2.5% in heart) and biokinetics in rabbits were satisfactory. The kit formulation was found to be stable and also safe for administration.

Animals↗

Leuprolide acetate in the management of ureteral obstruction caused by endometriosis.

Endometriotic ureteral obstruction is a serious event commonly diagnosed late and therefore associated with a major risk of hydronephrotic renal atrophy. The standard therapy is surgical. However, medical treatment has been reported using danazol, progestins, and estrogen-progestin combinations, although solid documentation of the effect of hormonal therapy against ureteral endometriosis is lacking. Gonadotropin-releasing hormone (GnRH) agonist treatment of endometriosis has yielded good results but has not been adequately reported in patients with ureteric involvement. We report three patients treated with a GnRH agonist, leuprolide acetate, for 6-9 months as a preoperative course. One patient had bilateral and two had unilateral obstruction. The preoperative course relieved the obstruction in the patient with bilateral disease and in one with unilateral changes. The failure occurred in a patient with intrinsic ureteric endometriosis. This early experience suggests a place for GnRH agonist therapy for patients with ureteric obstruction due to endometriosis, probably, but not necessarily, in conjunction with a planned surgical procedure. If medical therapy is attempted, close surveillance of renal function is mandatory.

Adult↗

Visualization of suppressed thyroid tissue by technetium-99m-tertiary butyl isonitrile: an alternative to post-TSH stimulation scanning.

The autonomously functioning thyroid nodule (AFTN) is a discrete, nodular structure which operates independently of pituitary control and without relation to the remaining thyroid tissue. Presently, for the visualization of a suppressed thyroid lobe, a patient has to undergo the thyrotropin (TSH) stimulation test, which has several disadvantages. In this study we have used tertiary butyl isonitrile (99mTc-TBI), well known as a myocardial imaging agent, for visualization of the suppressed lobe. Thirteen of fourteen patients studied demonstrated a contralateral lobe on a 99mTc-TBI scan which was not visualized with a 99mTc0(4) or 131I scan. Although it is not possible to demonstrate the autonomous nature of the hyperfunctioning thyroid nodule using 99mTc-TBI, we conclude that it is feasible to use this agent to visualize the lobe without the TSH test.

Adult↗

Synthesis and pharmacological study of antihyperlipaemic activity of 2-substituted thieno(2,3-d)pyrimidin-4(3H)-ones.

A series of 2-substituted thieno(2,3-d)pyrimidin-4-(3H) ones (1-15) was prepared by the reaction of thiophene ortho-aminoester (IV) with a variety of nitriles (V) under acidic conditions, and screened for antihyperlipaemic activity in various animal models. While most of these compounds were found active, 2-chloromethyl-5,6,7,8-tetrahydrobenzo(b)thieno(2,3-d) pyrimidin-4(3H)-one (5) was found to be the most active of all. The serum triglyceride lowering activity exhibited by 5 was found comparable to that of clofibrate and riboflavin tetrabutyrate. Compound 5 was also found to be safe as indicated by acute and chronic toxicity studies in mice and rats.

Animals↗

Clinical evaluation of 99mTc(V)-dimercapto succinic acid (DMSA) for imaging medullary carcinoma of thyroid and its metastasis.

99mTc(V)-DMSA kits developed by the Radiopharmaceutical Division, Bhabha Atomic Research Centre, have been evaluated for potential use in scanning medullary carcinoma of the thyroid and its metastases. There were 15 patients with proved medullary carcinoma and 6 patients with other differentiated thyroid carcinoma. Amongst the 15 patients with medullary carcinoma, 12 (80%) showed positive localisation either in the primary or one or more metastatic sites. None of the six patients with carcinoma other than medullary showed increased concentration of 99mTc(V)-DMSA. Of the 37 known metastatic sites in 15 patients with medullary carcinoma, 24 showed concentration of 99mTc(V)-DMSA (64.9%). In addition, 99mTc(V)-DMSA concentration was seen in 14 sites where no evidence of metastasis was revealed. The incidence of 99mTc(V)-DMSA concentration in soft tissue and bone metastasis was similar.

Adult↗