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Rajeev Kumar

Publications and source records attributed to Rajeev Kumar.

70 records · Page 4Linked to original sources
PubMed2002

Methods for programming and patient management with deep brain stimulation of the globus pallidus for the treatment of advanced Parkinson's disease and dystonia.

Globus pallidus (GPi) deep brain stimulation can markedly improve severe medication-refractory Parkinson's disease (PD) and dystonia. Appropriate perioperative patient management can assist with electrode implantation. Optimizing stimulation settings and simultaneously adjusting medications (when appropriate) can substantially improve patient outcomes. Although there are a large number of possible stimulation settings, in clinical practice, a relatively narrow range of settings has been shown to be most efficacious. A systematic approach to determining those settings that maximally improve parkinsonism and suppress drug-induced dyskinesias is outlined following a clear algorithm that uses the observation that stimulation of the dorsal and ventral pallidum has been shown to have opposite motor effects in PD. Based on the available literature, recommendations are also made for the use of GPi deep brain stimulation in dystonia.

Dystonia↗
PubMed2002

Malignant gonadal mesothelioma.

Malignant mesothelioma of the gonads is a rare and highly lethal disease. Most of these tumors arise from the tunica vaginalis, which is a continuation of the mesothelium similar to the pleura and the peritoneum. However, intratesticular and ovarian mesotheliomas have also been described. Occasionally, patients with localized disease at the time of detection have been known to survive for more than 10 years; however, the majority will not live beyond 5 years, with median survival being approximately 23 months. The principle reasons for this are difficulty in making a preoperative diagnosis and advanced stage at the time of treatment. Surgery forms the mainstay of management for all stages of the tumor. Adjuvant therapy in the form of chemotherapy, immunotherapy, or radiotherapy has negligible benefit. It is essential to diagnose this rare entity at the early stages to allow complete surgical extirpation. For the management of localized disease, we suggest the following protocol: initial staging of suspected cases with computed tomographic scan of the abdomen and pelvis; radical inguinal orchiectomy or hemiscrotectomy; retroperitoneal lymph node dissection in cases with positive nodes on scan or biopsy; and inguinal node dissection in cases requiring hemiscrotectomy. For advanced or recurrent disease, we suggest local radical resection with chemotherapy, including high-dose cisplatin and doxorubicin for two cycles of 5 days each; add local radiotherapy for uncontrolled locally advanced disease.

Genital Neoplasms, Male↗
PubMed2002

Zinc induces exposure of hydrophobic sites in the C-terminal domain of gC1q-R/p33.

Endothelial cells and platelets are known to express gC1q-R on their surface. In addition to C1q, endothelial cell gC1q-R has been shown to bind high molecular weight kininogen (HK) and factor XII (FXII). However, unlike C1q, whose interaction with gC1q-R does not require divalent ions, the binding of HK to gC1q-R is absolutely dependent on the presence of zinc. However, the mechanism by which zinc modulates this interaction is not fully understood. To investigate the role of zinc, binding studies were done using the hydrophobic dye, bis-ANS. The fluorescence intensity of bis-ANS, greatly increases and the emission maximum is blue-shifted from 525 to 485nm upon binding to hydrophobic sites on proteins. In this report, we show that a blue-shift in emission maximum is also observed when bis-ANS binds to gC1q-R in the presence but not in the absence of zinc suggesting that zinc induces exposure of hydrophobic sites in the molecule. The binding of bis-ANS to gC1q-R is specific, dose-dependent, and reversible. In the presence of zinc, this binding is abrogated by monoclonal antibody 74.5.2 directed against gC1q-R residues 204-218. This segment of gC1q-R, which corresponds to the beta6 strand in the crystal structure, has been shown previously to be the binding site for HK. A similar trend in zinc-induced gC1q-R binding was also observed using the hydrophobic matrix octyl-Sepharose. Taken together, our data suggest that zinc can induce the exposure of hydrophobic sites in the C-terminal domain of gC1q-R involved in binding to HK/FXII.

Binding Sites↗
PubMed2002

Autocystectomy following extensive genitourinary tuberculosis: presentation and management.

Genitourinary tuberculosis is an important cause of morbidity in developing and developed countries. We describe a case of extensive genitourinary tuberculosis in which there was complete destruction of the right kidney, stricture of the entire left ureter and an autocystectomized bladder. He presented in azotemia with urinary incontinence and was managed by right nephroureterectomy, ileal replacement of left ureter and ileal neobladder after a preliminary nephrostomy and antituberculous chemotherapy.

Adult↗
PubMed2002

Lycopene therapy in idiopathic male infertility--a preliminary report.

Excessive generation of reactive oxygen species (ROS) containing free oxygen radicals has been identified as one of the causes of male infertility. Lycopene is a component of human redox defence mechanism against free radicals. It is found in high concentrations in the testes and seminal plasma and decreased levels have been demonstrated in men suffering from infertility. We evaluated the effect of oral lycopene therapy in men with idiopathic infertility. Beginning March 2000, thirty men with idiopathic non-obstructive oligo/astheno/teratozoospermia were enrolled for the trial. All patients were administered 2000 mcg of Lycopene, twice a day for three months. Semen analysis was performed at three months and sperm concentration, motility and morphology were evaluated. All patients completed the trial without any complications. Twenty patients (66%) showed an improvement in sperm concentration, sixteen (53%) had improved motility and fourteen (46%) showed improvement in sperm morphology. In cases showing an improvement, the median change in concentration was 22 million/ml, motility 25% and morphology 10%. The improvement in concentration and motility were statistically significant. Baseline sperm concentration less than 5 million/ml was associated with no significant improvement. Higher baseline concentrations were associated with significant improvement and resulted in six pregnancies in 26 patients (23%). Oral Lycopene therapy seems to have a role in the management of idiopathic male infertility. Maximum improvement seems to occur in the sperm concentration (66% cases). Patients without severe oligospermia (sperm density > 5 million/ml) may be given a trial of therapy with lycopene. However, larger randomised controlled trials are essential before definitive therapeutic guidelines can be made.

Administration, Oral↗
PubMed2002

Retroperitoneoscopic adrenal surgery with reusable instruments.

BACKGROUND AND PURPOSE: Retroperitoneoscopic surgery has proven advantages over open surgery in terms of cosmesis, reduced postoperative pain, hospital stay, and early return to work. This is particularly true for surgery of the adrenal gland that otherwise entails a large surgical incision. One of the drawbacks of this surgery is the additional cost attributable to the disposable instruments. We present our cost-reductive retroperitoneoscopic techniques to tackle a variety of adrenal pathologies. PATIENTS AND METHODS: Beginning March 1995, 17 patients underwent cost-reductive retroperitoneoscopic adrenal surgery for various indications including 12 pheochromocytomas, 3 myelolipomas, 2 adrenal cortical adenomas, and two adrenal cysts. Two patients underwent simultaneous bilateral procedures for pheochromocytoma. A cost-reductive technique using minimal disposable equipment was employed. RESULTS: The procedure was completed in 18 of 19 cases (94%). One patient undergoing an adrenalectomy for pheochromocytoma was converted to open surgery because of nonprogress of the dissection. The largest tumor removed measured 10 cm. The mean operative time was 133 minutes, the average blood loss 169 mL, NSAID doses 3.56, and hospital stay 4.6 days. There were two major and two minor complications with no deaths. CONCLUSIONS: Cost-reductive retroperitoneoscopy is a feasible option for the management of a variety of adrenal pathologies. It should be considered a difficult procedure and be undertaken only by surgeons proficient in laparoscopy.

Adrenal Gland Neoplasms↗
PubMed2002

Stone granuloma--not to be forgotten as a delayed complication of ureteroscopy.

Endoscopic management of urolithiasis is one of the commonest urological procedures today. Its safety and efficacy in the management of ureteral calculi have been proven. A stone granuloma is a rare cause of recurrent ureteral obstruction subsequent to ureteroscopic stone removal. After its initial description by Dretler and Young [J Urol 1993;150:1800-1802] there have been sporadic reports of stone granuloma and paraureteral calculi secondary to iatrogenic perforations of the ureter and subsequent ureteric strictures as the cause of recurrent ureteral obstruction. We report two cases of delayed stone granuloma following pneumatic lithotripsy during ureteroscopy.

Adult↗
PubMed2002

Extraosseous Ewing's sarcoma of the kidney.

Extraosseous Ewing's sarcoma/primitive neuroectodermal tumor (EES/PNET) of the kidney is an uncommon entity and usually arises from the retroperitoneum and paraspinal region. We report a case of renal EES/PNET and discuss its clinical features, histological findings and management.

Adult↗
PubMed2002

Improved sampling of the pareto-front in multiobjective genetic optimizations by steady-state evolution: a pareto converging genetic algorithm.

Previous work on multiobjective genetic algorithms has been focused on preventing genetic drift and the issue of convergence has been given little attention. In this paper, we present a simple steady-state strategy, Pareto Converging Genetic Algorithm (PCGA), which naturally samples the solution space and ensures population advancement towards the Pareto-front. PCGA eliminates the need for sharing/niching and thus minimizes heuristically chosen parameters and procedures. A systematic approach based on histograms of rank is introduced for assessing convergence to the Pareto-front, which, by definition, is unknown in most real search problems. We argue that there is always a certain inheritance of genetic material belonging to a population, and there is unlikely to be any significant gain beyond some point; a stopping criterion where terminating the computation is suggested. For further encouraging diversity and competition, a nonmigrating island model may optionally be used; this approach is particularly suited to many difficult (real-world) problems, which have a tendency to get stuck at (unknown) local minima. Results on three benchmark problems are presented and compared with those of earlier approaches. PCGA is found to produce diverse sampling of the Pareto-front without niching and with significantly less computational effort.

Algorithms↗
PubMed2002

A nomogram for single-stage cluster-sample surveys in a community for estimation of a prevalence rate.

BACKGROUND: Proper assessment of the magnitude of the problem is essential for devising adequate allocation of available resources and for developing future strategies to combat a disease. The cluster random sampling (CRS) technique is commonly used for rapid assessment of public health problems in developing countries. Our objective is to devise a nomogram that can instantly provide the number of clusters of specified size needed to estimate the prevalence rate of a disease in a community with given precision, ratio of design-effect to cluster size and confidence level. This would be applicable only to single-stage CRS. METHODS: We use a logarithmic transformation to linearize the relation between the number of clusters (C) on one side and design-effect (D), cluster size (B), precision (L), anticipated prevalence rate (P) and confidence level (alpha) on the other. By using this relation, we construct a nomogram using established methods. RESULTS: A nomogram is obtained that can be used to determine the number of clusters needed in a survey with the help of only a ruler when other parameters are known. This is a 6-in-1 figure as it gives the number of clusters C corresponding to any combination of alpha from among the popularly used 0.05, 0.10 and 0.20, and precision 10% of P or 20% of P. Using a very simple calculation, the number of clusters for the other values of alpha and L can also be obtained. CONCLUSION: This nomogram can be a useful aid in instantly providing the number of clusters required to rapidly estimate the prevalence rate of a disease in a community when the ratio of design-effect to cluster size, confidence level, and precision are specified. However, it is not applicable to intervention studies where interest mainly focuses on testing a hypothesis rather than estimation.

Cluster Analysis↗
PubMedDate not supplied

Weekly alcohol consumption, brain atrophy, and white matter hyperintensities in a community-based sample aged 60 to 64 years.

OBJECTIVE: The objective of this study was to determine the association between weekly alcohol consumption and brain atrophy in adults aged 60 to 64 years. METHODS: Brain magnetic resonance imaging scans from 385 adults recruited through a community survey were analyzed. Automated segmentation and manual tracing methods were used to obtain brain subvolumes and automated methods were used to obtain quantification and localization of white matter hyperintensities. Visual measures of cortical atrophy were obtained as were data on health and lifestyle factors. Alcohol consumption was assessed with the Alcohol Use Disorders Identification Test. RESULTS: In men, weekly alcohol consumption had a positive linear association with ventricular volume and gray matter and a negative linear association with white matter. In women, weekly alcohol consumption had a nonlinear relationship with cerebrospinal fluid and white matter. Alcohol consumption was not associated with white matter hyperintensities, corpus callosum size, hippocampal or amygdala volumes in analyses adjusting for confounding variables. CONCLUSION: An association between alcohol consumption and brain atrophy is evident at the population level. In women, detrimental effects of alcohol on the brain appear to occur at lower levels of consumption. It remains possible that low levels of alcohol consumption have neuroprotective benefits but is clear that high levels of consumption are detrimental.

Alcohol Drinking↗
PubMedDate not supplied

Estimates of the years-of-life-lost due to the top nine causes of death in rural areas of major states in India in 1995.

BACKGROUND: Years-of-life-lost (YLL) contribute nearly two-thirds of the disability-adjusted life-years (DALYs) worldwide and are especially Important for India where infant and child mortality is still high. These were estimated for India under the Global Burden of Disease study for the year 1990. No estimates are available for the different states of India. We aimed to prepare state-wise estimates of YLL for different causes of death in rural areas and to determine the causes responsible for a higher burden in different states. METHOD: Percentage deaths of the top 9 causes reported in the Registrar-General's Survey of Causes of Deaths (Rural)--1995 in 13 major states of India and different age groups was applied to the expected number of total deaths. The life lost according to the standard life-table was age-weighted and discounted using the methodology of the Global Burden of Disease 1990 study. The causes of death were based on lay reporting which otherwise seem reliable. RESULTS: The all-cause YLL in rural India in 1995 were 207 per 1,000 population. The minimum was 74 in Kerala and maximum 276 in Madhya Pradesh. Pneumonia was the top cause responsible for 15 YLL. The inter-state variation was high as Tamil Nadu had only 1.6 and Uttar Pradesh 30.5 YLL from this cause. Cancers were a uniform burden across the states. Heart attack, and bronchitis and asthma cut across the more and less developed states. Suicides were a heavy burden in Andhra Pradesh and vehicular accidents in Haryana and Rajasthan. Bihar, Gujarat, Madhya Pradesh, Orissa, Rajasthan and Uttar Pradesh had communicable and nutritional conditions as predominant causes while Kerala and Punjab had non-communicable diseases as the predominant cause of YLL due to premature mortality. CONCLUSION: These results provide a new perspective about the causes of death that need more attention in rural areas of different states of India. These will also help prioritize areas which require more inputs at the state-level and hence will be useful for health policymakers.

Adolescent↗
PubMedDate not supplied

Retroperitoneoscopic adrenalectomy for pheochromocytoma: comparison with open surgery.

OBJECTIVES: To evaluate the feasibility of the retroperitoneoscopic approach to adrenalectomy for pheochromocytoma and to compare it with the open retroperitoneal approach. METHODS: Twelve retroperitoneoscopic adrenalectomies for pheochromocytomas were performed in 10 patients at our center between January 1996 and January 2001. Two patients underwent simultaneous bilateral surgeries. These were retrospectively compared with open adrenalectomy for pheochromocytoma through the extraperitoneal flank approach in 6 patients with 7 adrenalectomies, conducted during the same period. RESULTS: Retroperitoneoscopic adrenalectomy could be successfully performed in 11 cases with 1 conversion to open surgery. Mean operative time was 151 minutes (range, 90 to 200 min). This was comparable to the time for the open surgery group, 169 minutes (range, 85 to 270 min). However, the mean blood loss of 140 mL (range, 30 to 300 mL), hospital stay of 4.4 days, and analgesia doses required (3.3) were significantly lower than those for the open surgery group (592 mL, 9.8 days, and 8.1 doses, respectively). No significant intraoperative hypertensive crises occurred in either group. CONCLUSIONS: Retroperitoneoscopy is a safe and feasible option for adrenalectomy for pheochromocytoma. It requires shorter operative time, less postoperative analgesia, a shorter hospitalization, and blood loss is less. Although retroperitoneoscopy is widely practiced for other adrenal tumors, it should now also be considered for pheochromocytomas.

Adolescent↗
PubMedDate not supplied

Pattern of metastases in renal cell carcinoma: a single institution study.

BACKGROUND: Increasing numbers of patients with renal cell carcinoma (RCC) are incidentally detected and can be potentially cured by surgery alone. In treating metastatic RCC, worthwhile survival rates are achieved in cases of low burden recurrences. This necessitates a rational follow up protocol, which picks up early recurrences and avoids costly surveillance for those with a favorable prognosis. AIMS: We studied the patterns of metastases occurring in patients operated for localized or locally advanced renal cell carcinoma in the Indian setting and try to evolve a suitable follow up protocol. SETTING AND DESIGN: Institution based, retrospective data. METHOD AND MATERIALS: Records of patients from January 1988 to December 2003, operated for initially localized RCC were reviewed. Follow up was performed using an established protocol. Occurrence of metastases and their patterns were studied. STATISTICAL ANALYSIS USED: Comparison of the different survival times was performed using the one-way analysis method. Multiple comparisons (post hoc test) were performed using the Bonferroni method. RESULT: Follow up was available on 209 patients. Mean survival was 43.75 months (SD +/- 28.72). Thirty-nine patients developed 59 metastases. Lungs were the commonest site of metastases (37%), followed by bone (22%), liver (19%) and brain (8%). Relapse and survival showed significant correlation with pathological stage (p CONCLUSIONS: Occurrence of metastases correlate with the pathological stage of the disease at primary presentation. Tailored, stage-based follow up protocols allow adequate surveillance for disease activity and progression without escalating the overall costs.

Biopsy, Needle↗
PubMedDate not supplied

Role of testicular fine-needle aspiration cytology in infertile men with clinically obstructive azoospermia.

BACKGROUND: Azoospermia due to obstruction of the vaso-epididymal junction is one of the few surgically correctable causes of male infertility. In patients where all clinical and laboratory parameters suggest a vaso-epididymal junction block amenable to surgery, failure to find normal spermatogenesis on fine-needle aspiration cytology (FNAC) of the testis may necessitate a change in treatment modality to the more expensive intracytoplasmic sperm injection. We evaluated the validity of FNAC findings in predicting failure of surgical exploration when clinical parameters suggest otherwise. METHODS: Infertile, azoospermic men in whom the semen volume and fructose content, testis size, follicle-stimulating hormone level were normal and the vas deferens was palpable with no evident cause for obstruction, underwent FNAC of the testis to confirm the presence of normal spermatogenesis before surgical exploration. Men with hypospermatogenesis or maturation arrest on FNAC and a normal karyotype with absence of Y chromosome microdeletion were offered assisted reproduction or surgical exploration to identify a reconstructable obstruction. Men who chose surgery were included in the study and the findings on exploration were compared with the FNAC reports. RESULTS: Of the 10 men who satisfied the inclusion criteria, 6 had hypospermatogenesis and in 4 FNAC showed maturation arrest. On surgical exploration, none had sperm in the epididymis. A biopsy of the testis taken at the time of exploration confirmed the FNAC findings. CONCLUSION: Clinical parameters are insufficient for diagnosing obstructive azoospermia. FNAC can accurately evaluate the testicular pathology and predict whether or not surgical exploration should be undertaken.

Adolescent↗