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A K Patel

Publications and source records attributed to A K Patel.

At least 19 recordsLinked to original sources
PubMed2006

Botulinum toxin injection therapy in the management of lower urinary tract dysfunction.

We have great pleasure in introducing this supplement containing a collection of articles reviewing the contemporary clinical management of functional disorders of the lower urinary tract (LUT) with particular emphasis on the potential role of botulinum toxin injection therapy. Detrusor sphincter dyssynergia (DSD), detrusor overactivity (DO), painful bladder syndrome (PBS) and LUT symptoms consequent on bladder outflow obstruction (LUTS/BPH) have all been treated by the injection of botulinum toxin. This treatment can be administered as a minimally invasive, outpatient procedure which on the initial trials for DO (particularly of neurogenic aetiology) shows a remarkable efficacy with effects lasting up to a year after a single treatment with few significant side effects. Success has been reported with the management of detrusor sphincter dyssynergia and preliminary series report positive outcomes in the management of PBS and LUTS/BPH. However, most of the studies to date include small numbers and have a recruitment bias with few randomised controlled trials having been reported. The answers to some of the key questions are addressed with reference to our contemporary knowledge. It is clear that considerable work both clinical and basic science still needs to be performed to answer the many remaining questions with regard to this treatment modality but undoubtedly it will be a major future treatment option in those with intractable symptoms or those unable to tolerate medications. Currently, all botulinum toxin use for urological conditions is off-label and unlicensed, therefore caution should be exercised until future large randomised studies are reported.

Botulinum Toxins, Type A↗
PubMed2006

The emerging role of intravesical botulinum toxin therapy in idiopathic detrusor overactivity.

Recently there has been considerable original research into the use of the botulinum neurotoxins in idiopathic detrusor overactivity (DO). This common condition underlies the overactive bladder syndrome in a significant proportion of cases and was previously known as idiopathic detrusor instability. Failure of initial pharmacotherapy in this condition leaves few effective conservative/medical treatment options. Early reports of botulinum toxin (BoNT) therapy have been extremely promising, and the therapy appears to bridge the gap in such patients, before resorting to invasive surgical procedures. Approximately 30 studies have been reported often with widely differing techniques and some clinicians are beginning to administer BoNT for this unlicensed indication. This has led to the urgent need to critically review all available evidence to assess efficacy, safety and technique. In addition to performing a systematic Medline review, all abstracts presented to urological, urogynaecological and incontinence meetings that reported BoNT usage in idiopathic DO were analysed. Remarkable efficacy has been demonstrated in the vast majority of reported series and the treatment has also been used safely in paediatric and elderly populations. Side effects in all populations appear to be minimal and short lived. However, all the series are small and there remains a considerable number of fundamental questions to be answered. Hopefully large-scale robust randomised controlled trials will provide the necessary answers to facilitate the widespread adoption of this technique. Until then caution must be exercised in this unlicensed indication.

Aged↗
PubMed2006

API consensus guidelines for use of antiretroviral therapy in adults (API-ART guidelines). Endorsed by the AIDS Society of India.

With rational use of antiretroviral therapy (ART), human immunodeficiency virus (HIV) infection has been transformed into a chronic manageable illness like diabetes and hypertension. These guidelines provide information on state of art, evidence based approach for use of ART in Indian context. When to initiate ART? Antiretroviral therapy is indicated for all symptomatic HIV infected persons regardless of CD4 counts and plasma viral load (PVL) levels. In asymptomatic patients, ART should be offered when the CD4 counts < 200/mm3 and should be considered in patients with CD4 counts between 200-250/mm3. Therapy is not recommended for patients with CD4 count more than 350/ mm3. Involvement of patient in all treatment decisions and assessing readiness is critical before initiating ART. What to start with? A non-nucleoside reverse transcriptase inhibitor (NNRTI) based regimen is recommended for antiretroviral naïve patients. The choice between nevirapine and efavirenz is based on differences in adverse events profiles; cost and availability of convenient fixed dose combinations and need for concomitant use of rifampicin. A backbone of 2-nucleoside reverse transcriptase inhibitors (NRTIs) is combined with the NNRTI. Various combinations and ART strategies not to be used in clinical practice has been enlisted. How to follow up? Recommendations have been made for baseline evaluation and monitoring of patients on ART. These include guidelines on laboratory and clinical evaluation. A plasma viral load at 6 months after initiation of first-line ART is strongly recommended. Yearly estimation of lipid profile has been recommended. How to identify and manage ART failure? The guidelines recognize the issue of identifying ART failure late if only CD4 counts are used for monitoring. In the absence of resistance testing various second-line regimens have been enlisted. A boosted protease inhibitor based regimen is recommended in this situation to be combined with 2-NRTIs. Special situations Recommendations have been made for use of ART in HIV-TB, HIV-HBV, and HIV-HCV co-infected patients. In patients with active TB and a CD4 count < 200/mm3, initiation of ART is recommended as soon as the anti-TB treatment is tolerated. Efavirenz is the only ARV drug, which can be safely used with rifampicin. In pregnancy use of single dose nevirapine for reducing risk of mother to child transmission of HIV is not recommended, because of the risk of development of resistance. For post-exposure prophylaxis taking ART treatment history of the source patient is crucial in designing an effective regimen.

Acquired Immunodeficiency Syndrome↗
PubMed2004

Lactic acidosis in HIV-I infected patients receiving antiretroviral therapy.

Highly active antiretroviral therapy (HAART) has resulted in dramatic declines in morbidity and mortality in HIV-I infected patients in the developed world. However, with the availability of generic antiretroviral treatments (ART) in India, a large number of patients now receive ART. Increase in experience with ART has led to the detection of drug-related toxicities. We report herein potentially fatal side effects associated with the use of nucleoside analogues in HIV treatment--hyperlactatemia and lactic acidosis/hepatic steatosis.

Acidosis, Lactic↗
PubMed2001

Compatibility of the thioamide functional group with beta-sheet secondary structure: incorporation of a thioamide linkage into a beta-hairpin peptide.

[structure: see text]. We report the incorporation of a thioamide linkage between the i + 2 and i + 3 residues of the type II' beta-turn of a peptide known to fold into a beta-hairpin conformation. Two-dimensional NMR spectroscopy and circular dichroism spectroscopy indicate that the thioxo peptide adopts a hairpin conformation similar to that of the oxo peptide and that the hairpin conformation persists at elevated temperatures. The results show that a thioamide linkage is compatible with beta-sheet secondary structure.

Circular Dichroism↗
PubMed2001

Autoamputation of the tongue.

Autoamputation is an uncommon phenomenon that has been reported for the fingers, toes, appendix, ovary, spleen, etc. Autoamputation of the tongue has never been reported. An elderly man with carcinoma of lateral pharyngeal wall and tonsil presented with an autoamputated tongue that was attached to the oral cavity with a thin band. The patient required detachment of the tongue and tracheostomy followed by radiotherapy for the primary tumour.

Aged↗
PubMed1998

Fungal purulent constrictive pericarditis in a heart transplant patient.

Purulent pericarditis caused by Candida species is rare and is associated with very high mortality. Immunosuppressed transplant patients are particularly susceptible to fungal infections. We report a case of Candida purulent constrictive pericarditis in an immunocompromised heart transplant patient who was treated successfully with antifungal agents, surgical drainage, and pericardiectomy.

Amphotericin B↗
PubMed1998

Radiation therapy in pseudotumour haemarthrosis.

Total or partial deficiency of factor VIII and IX in the coagulation cascade leads to haemophilia. Haemophilia affecting weight-bearing joints gives a 'pseudotumour' or haemarthrosis-like condition. Surgery and cryoprecipitate infusions have been the treatment for this condition. Radiocolloids and radiation therapy have been used with some benefit. One case of ankle pseudotumour which was treated by low-dose external beam radiation is presented here.

Adolescent↗
PubMed1996

Magnetic resonance imaging: an accurate method to evaluate arteriovenous malformations after stereotactic radiosurgery.

To determine the accuracy of magnetic resonance (MR) imaging in comparison to cerebral angiography after radiosurgery for an arteriovenous malformation (AVM), the authors reviewed the records of patients who underwent radiosurgery at the University of Pittsburgh Medical Center before 1992. All patients in the analysis had AVMs in which the flow-void signal was visible on preradiosurgical MR imaging. One hundred sixty-four postradiosurgical angiograms were obtained in 140 patients at a median of 2 months after postradiosurgical MR imaging (median 24 months after radiosurgery). Magnetic resonance imaging correctly predicted patency in 64 of 80 patients in whom patent AVMs were seen on follow-up angiography (sensitivity 80%) and angiographic obliteration in 84 of 84 patients (specificity 100%). Overall, 84 of 100 AVMs in which evidence of obliteration was seen on MR images displayed angiographic obliteration (negative predictive value, 84%). Ten of the 16 patients with false-negative MR images underwent follow-up angiography: in seven the lesions progressed to complete angiographic obliteration without further treatment. Exclusion of these seven patients from the false-negative MR imaging group increases the predictive value of a negative postradiosurgical MR image from 84% to 91%. No AVM hemorrhage was observed in clinical follow up of 135 patients after evidence of obliteration on MR imaging (median follow-up interval 35 months; range 2-96 months; total follow up 382 patient-years). Magnetic resonance imaging proved to be an accurate, noninvasive method for evaluating the patency of AVMs that were identifiable on MR imaging after stereotactic radiosurgery. This imaging modality is less expensive, more acceptable to patients, and does not have the potential for neurological complications that may be associated with cerebral angiography. The risk associated with follow-up cerebral angiography may no longer justify its role in the assessment of radiosurgical results in the treatment of AVMs.

Humans↗
PubMed1996

Transthoracic and transesophageal echocardiographic evaluation of the aortic root and subvalvular structures in ankylosing spondylitis.

OBJECTIVE: During the preclinical phase of cardiac involvement in ankylosing spondylitis (AS), examination, electrocardiography, and transthoracic echocardiography (TTE) may lack the sensitivity to detect cardiac abnormalities. Since transesophageal echocardiography (TEE) allows a closer view of the aortic root and subvalvular structures we investigated whether preclinical abnormalities of the aortic root and subvalvular structures could be detected. METHODS: Clinical and echocardiographic (TTE and TEE) evaluation of 29 male patients with AS and 13 age matched controls. RESULTS: No patient with AS had a high degree heart block. Aortic root dimensions were comparable between the study groups, but the anterior aortic wall was thinner in patients with AS than controls, 0.25 and 0.41 cm, respectively (p = 0.016). The posterior aortic wall was thicker and subjectively more echogenic than the anterior wall in 17/29 patients with AS compared to 4/13 controls. Aortic valve insufficiency was detected with TEE in 10/29 patients with AS. In 8/9 patients with AS studied with TEE, the subaortic structures were thickened and/or of increased echogenicity. This abnormal echo extended into the membranous septum. CONCLUSION: Abnormal subvalvular echoes consistent with fibrosis of the aortic root and membranous interventricular septum were detected with TEE but not TTE. The use of TEE may allow earlier diagnosis of cardiac involvement in AS.

Adult↗
PubMed1995

An improved assay for antibody dependent cellular cytotoxicity based on time resolved fluorometry.

A new and faster assay for antibody dependent cellular cytotoxicity based on release of europium from target cells is described. This has a number of important advantages over the traditional assays based on release of chromium-51 (51Cr). The new method involves labelling of Wein 133 target cells (B cell non-Hodgkin's lymphoma cells) which express the antigen, CDw52, with the chelate europium diethylenetriaminopentaacetic acid (EuDTPA) according to the method of Blomberg et al. (1986). Labelled cells are sensitised (coated) with the anti-lymphocytic monoclonal antibody, Campath-1H. Human peripheral blood mononuclear cells are added to mediate lysis of EuDTPA labelled Wein 133 cells by ADCC. Release of EuDTPA from lysed cells is determined by mixing supernatants with enhancement solution containing 2-naphthoyl trifluoroacetone, 2-NTA, to form a highly fluorescent chelate which is measured using time resolved fluorometry. Results obtained with the new EuDPTA release assays were comparable to traditional assays based on the release of the radioisotope 51Cr. It is anticipated that this assay will have a widespread application among laboratories performing ADCC assays. The method is non-hazardous and has been used routinely for over 2 years to monitor production and purification of Campath-1H.

Animals↗
PubMed1995

The effect of the removal of sialic acid, galactose and total carbohydrate on the functional activity of Campath-1H.

A monoclonal human IgG1, Campath-1H, was digested with glycosidases to assess the effect of carbohydrate on the functional activities of an IgG1. Removal of the complete carbohydrate moiety abolished complement lysis activity and antibody-dependent cell-mediated cytotoxicity, but left antigen binding activity and protein A binding activity intact. Removal of terminal sialic acid residues through glycopeptidase F digestion was not found to affect any of the tested IgG activities. Removal of the majority of the galactose residues from desialylated Campath-1H was found to reduce but not abolish complement lysis activity. Other activities were not affected by degalactosylation. This indicates a rare separation of complement lysis activity and antibody-dependent cell-mediated cytotoxicity of IgG in the way they behave under controlled conditions. This paper underlines the overall importance of carbohydrate in IgG function and stresses the relative contributions of some of the carbohydrate residues.

Alemtuzumab↗