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Rajeev Kumar

Publications and source records attributed to Rajeev Kumar.

At least 37 records · Page 2Linked to original sources
PubMed2005

Long-term safety, efficacy, dosing, and development of resistance with botulinum toxin type B in cervical dystonia.

Short-term studies of cervical dystonia (CD) have demonstrated botulinum toxin type B (Bot B) to be safe and efficacious at doses of 5,000 to 10,000 units, but few long-term studies have been published and the safety and efficacy of higher doses has not been established. Additionally, there are few studies describing the development of resistance to Bot B in those with and without prior resistance to botulinum toxin type A (Bot A). We reviewed our experience with 24 patients treated with Bot B for up to 64 months. Patients were treated with Bot B for 26.2 +/- 20.4 months (range, 3-64 months) with a mean treatment dose of 14,828 +/- 6,824 units (range, 2,500-28,000 units). At last follow-up, 12 patients demonstrated ongoing benefit, 8 patients had become secondarily resistant, and 4 patients were primary nonresponders possibly due to the severity and nature of their CD. Nine of the 12 continued responders and 7 of the 8 secondary nonresponders to Bot B had prior probable or definite clinical resistance to Bot A. No severe adverse events related to Bot B were seen. Treatment of patients with severe CD who continue to show a beneficial response to Bot B injections commonly requires doses of 15,000 units and rarely greater than 20,000 units. Patients may continue to respond for up to 64 months. Prior Bot A resistance may be a risk factor for the development of resistance to Bot B; nevertheless, Bot B can be a useful long-term alternative in some Bot A-resistant CD patients.

Adult↗
PubMed2005

Separated quadrupolar field experiment.

We describe an NMR experiment that produces spectra correlating the first-order quadrupolar spectrum and the central transition spectrum of half-integer quadrupolar spins, allowing one to separate the quadrupolar parameters in overlapping spectra under both static and magic-angle-spinning conditions. Promising fields of applications include situations where the sample cannot easily be rotated, or where it cannot be rotated at the magic angle.

Magnetic Resonance Spectroscopy↗
PubMed2005

Retroperitoneoscopic decortication of symptomatic renal cysts.

PURPOSE: To determine the safety and efficacy of retroperitoneoscopic decortication of symptomatic renal cysts. PATIENTS AND METHODS: A total of 24 patients with symptomatic 6- to 14-cm (mean 10.9-cm) simple renal cysts, right sided in 13 and left sided in 11, underwent retroperitoneoscopic decortication for pain relief at our center between January 1997 and December 2002. The diagnosis was based on an ultrasonogram and contrast-enhanced CT. Symptom severity, assessed using a visual analog pain scale, averaged 7.2/10 (range 6.5-9). The mean duration of symptoms was 4 months. Operative and follow-up data were collected prospectively and analyzed for symptomatic and objective evidence of improvement. RESULTS: The mean operating time was 95 minutes, and no major complications were observed. The average hospital stay was 2.9 days (range 2-7 days). At a mean follow-up of 2.8 years (range 1.5-5 years), pain relief was reported by 22 patients (change of pain score from 7.2 to 1.4). One patient had worsening of pain at 6 weeks postoperatively. Asymptomatic recurrence of the cyst was seen in two patients on the follow-up ultrasound scans. CONCLUSIONS: Retroperitoneoscopic renal-cyst decortication is a safe, minimally invasive, and efficacious procedure for the treatment of painful renal cysts, with a durable response.

Adult↗
PubMed2005

Simultaneous laparoscopic adrenalectomy for pheochromocytoma and dismembered pyeloplasty for uretero-pelvic junction obstruction.

Laparoscopic adrenalectomy for pheochromocytoma and laparoscopic dismembered pyeloplasty are both technically difficult procedures. We describe the case of a 61-year-old female patient who presented with a right adrenal pheochromocytoma and bilateral pelvi-ureteric junction obstruction with renal failure who underwent a successful simultaneous transperitoneal laparoscopic adrenalectomy and pyeloplasty.

Acute Kidney Injury↗
PubMed2005

Contribution of investigations to the diagnosis of bilateral vas aplasia.

BACKGROUND: Bilaterally absent vas deferens is a surgically uncorrectable cause of male infertility. It is usually diagnosed clinically. We evaluate the role of semen analysis and radiological imaging in providing objective evidence of vas aplasia. METHODS: Twenty consecutive patients with clinically suspected bilateral vas aplasia were enrolled for this prospective study. They were investigated on the basis of an algorithm till corroborative evidence for vas aplasia was obtained. This successively included a semen analysis on at least two occasions, transrectal ultrasonogram (TRUS), pelvic magnetic resonance imaging (MRI) and scrotal exploration. The contribution of each investigation to confirming the diagnosis was evaluated. RESULTS: Seventeen patients (85%) had a low volume ejaculate while all 20 had azoospermia and semen fructose levels below normal. Semen pH was non-acidic in 75% of cases and thus was not contributory to the diagnosis. TRUS and MRI were non-contributory in 30% and 50% of evaluations, respectively. The clinical diagnosis was found to be correct in all patients. CONCLUSIONS: Vas aplasia is a clinical diagnosis. Low volume ejaculate with azoospermia and low or absent semen fructose is sufficient corroborative evidence and no further investigations are required for this diagnosis.

Adult↗
PubMed2005

MRI hyperintensities and depressive symptoms in a community sample of individuals 60-64 years old.

OBJECTIVE: Previous studies have found associations of magnetic resonance imaging (MRI) signal hyperintensities with depression in the elderly. The present study investigates the association in a younger community sample (age 60-64 years) of depressed subjects and comparison groups for potential mediating and confounding variables. METHOD: A subsample of 475 persons 60-64 years of age from a larger community survey underwent brain MRI scans. White matter hyperintensities were quantified by using an automated procedure, and basal ganglia hyperintensities were quantified by using semiquantitative visual ratings. The study also assessed depressive symptoms and use of antidepressant medication. Potential mediating or confounding variables assessed included physical disability, hypertension, stroke, diabetes, head injury, cortisol, thyroid-stimulating hormone, cognitive functioning, smoking, and alcohol use. RESULTS: Depressive symptoms were found to be related to total brain white matter hyperintensities but not to basal ganglia hyperintensities. However, associations disappeared when statistical adjustment was made for physical disability and smoking. CONCLUSIONS: Depressive symptoms are related to white matter hyperintensities in mid-adult life in a community sample. Physical disability appears to play an important role in this association.

Age Factors↗
PubMed2005

Social class and all-cause mortality in an urban population of North India.

BACKGROUND: There is a rapid emergence of cardiovascular disease in India with economic development, leading to an increase in mortality due to these diseases. The exact causes of death in India, however, are not known. SUBJECTS AND METHODS: We studied randomly selected death records from 2222 (1385 men and 837 women) victims, aged 25-64 years, out of 3034 death records during 1999-2001 at the Municipal Corporation, Moradabad. All the families of these victims could be contacted individually to find out the causes of death, by scientists/doctors-administered pre-tested verbal autopsy questionnaires, completed with the help of spouses and local treating doctors practising in the concerned lane. Social classes were assessed by a questionnaire based on attributes of per capita income, occupation, education, housing and ownership of consumer luxury items in the household. RESULTS: Causes of mortality included infectious diseases (41.1%, n = 915) such as tuberculosis, pneumonia, chronic obstructive pulmonary disease, diarrhea/dysentery, hepatitis B, and inflammatory brain infections as the commonest causes of death in the urban population of North India. The second most common causes of death were circulatory diseases (29.1%, n = 646), including heart attacks (10.0%), strokes (7.8%), valvular heart disease (7.2%, n = 160), sudden cardiac death, and inflammatory cardiac disease (each 2.0%, n = 44). Malignant neoplasm (5.8%, n = 131), injury (14.0%, n = 313), including accidents, fire and falls, and poisonings were also quite common causes of death. Miscellaneous causes of death were noted in 9.1% (n = 202) death records, including diabetes mellitus (2.2%, n = 49), suicides (1.8%, n = 41), congenital anomalies (1.0, n = 37), dental caries infections (1.9, n = 42), and burns (1.3%, n = 33). Pregnancy and perinatal causes (0.72%, n = 15) were not commonly recorded in our study. Circulatory diseases as the cause of mortality were statistically significantly more common among higher social classes (1-3) than in lower social classes (4 and 5) whose members died more often due to infections. Heart attacks, strokes, hypertension, diabetes and obesity were statistically significantly more common among higher social classes (1-3) as compared to classes 3 and 4, but tobacco intake showed only minor differences among various classes. CONCLUSIONS: This study indicates that circulatory diseases, injury and malignant diseases have become the major causes of death in India, after infections. Members of social classes 1-3 died more often due to circulatory diseases and members in lower social classes died more often due to infections. Urbanization with rapid changes in diet and lifestyle in various social classes, and possibly aging of the population seem to be responsible for the double burden of diseases, related to under- and over-nutrition, causing death in a developing economy. Monitoring of blood pressure and heart rate around the clock for 7 days, with data analysed chronobiologically can detect abnormal circadian patterns associated with a large increase in cardiovascular disease risk, greater than hypertension itself, allowing the institution of prophylactic treatment. Such prehabilitation may be particularly useful to curb the increasing burden of cardiovascular diseases in both developed and developing countries.

Adult↗
PubMed2004

Prevalence of mild cognitive impairment in 60- to 64-year-old community-dwelling individuals: The Personality and Total Health through Life 60+ Study.

This epidemiological study aimed at determining the prevalence of mild cognitive impairment (MCI) in 60- to 64-year-old individuals using different diagnostic criteria. Community dwelling individuals (n = 2,551) in the age range of 60-64 years were recruited randomly through the electoral roll. They were screened using the MMSE and a short cognitive battery, and those who screened positive underwent detailed medical and cognitive assessments. Extant MCI-related diagnoses were established by consensus. Predictive regression models on the sub-sample were used to determine population prevalence for the diagnoses. Of the 224 subjects who screened positive for MCI, 112 underwent a detailed assessment and 74% met the criteria for at least one recognised diagnosis of mild cognitive deficit (MCI and related diagnoses). By predictive regression modelling, the prevalence of any MCI diagnosis was 13.7% (95% CI 9.1-30.2) in the population of 60- to 64-year-olds. The estimated prevalence rates for specific diagnoses were: MCI 3.7%, ageing-associated cognitive decline 3.1%, Clinical Dementia Rating score (0.5) 2.8%, age-associated memory impairment 1%, other cognitive disorders 0.9%, and mild neurocognitive disorder 0.6%. Agreement on 'caseness' between various proposed diagnoses was at best fair and generally poor. Memory and other cognitive problems not meeting the threshold for dementia are relatively common in 60- to 64-year-old individuals living in the community. The prevalence rate varies up to six-fold according to the diagnostic criteria applied, with limited overlap between diagnoses. There is an urgent need for standardization of the criteria.

Activities of Daily Living↗
PubMed2004

Oxasmaragdyrin-ferrocene and oxacorrole-ferrocene conjugates: synthesis, structure, and nonlinear optical properties.

Ferrocenyl macrocyclic conjugates involving 22 pi oxasmaragdyrins and 18 pi oxacorroles have been synthesized and characterized. The direct covalent linkage of the ferrocenyl moiety to the meso position of the macrocycle is achieved by simple oxidative coupling of appropriate precursors with trifluoroacetic acid as catalyst. The electronic coupling between the ferrocenyl moiety and the macrocyclic pi system is apparent from: a) the red shifts (293-718 cm(-1)) of the Soret and Q-bands in the electronic absorption spectra of ferrocenyl conjugates; b) the shift of oxidation potentials (50-130 mV) of both the ferrocene and the corrole rings to the positive potentials; and c) considerable shortening of the C-C bond which connects the ferrocene and the meso-carbon atom of the macrocycle. The single-crystal X-ray structure of oxasmaragdyrin-ferrocene conjugate 9 reveals the planarity of the 22 pi skeleton with very small deviations of the meso-carbon atoms. The meso-ferrocenyl substituent has a small dihedral angle of 38 degrees, making way for mixing of the molecular orbitals of the ferrocene and the macrocycle. However, the other two meso substituents are almost perpendicular to the mean plane, defined by the three meso carbon atoms. Classical C-H...O and nonclassical C-H...pi interactions lead to a two-dimensional supramolecular network. Ferrocene-smaragdyrin conjugate 9 bonds to a chloride ion in the protonated form and a rhodium(i) ion in the free base form. Nonlinear optical measurements reveal a larger nonlinear refractive index (-5.83 x 10(-8)cm(2)W(-1)) and figure of merit (2.28 x 10(-8)cm(3)W(-1)) for the rhodium smaragdyrin-ferrocene conjugate 19 than for the others, suggesting its possible application in optical devices.

Journal Article↗
PubMed2004

Homocysteine and the brain in midadult life: evidence for an increased risk of leukoaraiosis in men.

BACKGROUND: High serum homocysteine (HCY) levels have been associated with thromboembolic cerebrovascular disease, but their relationship to microvascular disease is uncertain. Homocysteine also has a direct neurotoxic effect and has been linked to brain atrophy and an increased risk of Alzheimer disease. OBJECTIVE: To examine the relationship of HCY levels to brain and cognitive measures in a healthy community sample. DESIGN: Cross-sectional study. SETTING: Individuals residing in Canberra and Queanbeyan, Australia, who were participating in the longitudinal PATH Through Life Project. PARTICIPANTS: Individuals aged 60 to 64 years selected randomly from the community, 196 men and 189 women. MAIN OUTCOME MEASURES: Regression coefficients with HCY level as the putative determinant and various magnetic resonance imaging measures (brain atrophy index, ventricle-brain ratios, volume of periventricular and deep white matter hyperintensities) and cognitive measures (information processing speed, verbal memory, fine motor speed) as dependent measures. RESULTS: Homocysteine levels did not have a significant relationship with brain atrophy index or ventricle-brain ratios. High HCY levels were related to increased deep white matter hyperintensities but not periventricular white matter hyperintensities, after correcting for levels of folate, vitamin B(12), creatinine, and thyrotropin; hypertension; smoking; and diabetes, the relationship being significant only in men. Homocysteine levels were related to impairment in verbal memory and fine motor speed but not after the previously mentioned correction. CONCLUSIONS: Total HCY level is independently related to leukoaraiosis in middle-aged men, and this may be functionally relevant in the form of mild cognitive impairment. The remediation of hyperhomocysteinemia should begin early in life if its deleterious effects on the brain are to be prevented.

Brain↗
PubMed2004

Radical cystectomy in septuagenarian patients with bladder cancer.

INTRODUCTION: Clinical results of radical cystectomy performed on elderly bladder cancer patients over 70 years old were assessed to determine whether age is one of the critical points for the application of this type of surgery. MATERIALS: From January 1992 to December 2002, 41 radical cystectomy performed in septuagenarian population were compared with 197 performed in patients less than 70 years of age. RESULTS: The early and late complication rate for septuagenarians was 29.7% and 12%, compared with 26.9% and 9.6% for patients younger than 70 years respectively. The overall mortality rate for septuagenarians was 4.9%, compared with 8.6% for patients younger than 70 years. There was no significant difference between the two groups with regard to pathologic stage or length of hospital stay. The 5-year overall survival rate for septuagenarians was 53% compared with 59% for patients younger than 70 years. CONCLUSIONS: When indicated after adequate preoperative assessment and optimization of the patient, radical cystectomy is a safe procedure in the septuagenarians and patient should not be denied surgery dependent on chronologic age.

Aged↗
PubMed2004

Renal cell cancer in solitary kidney after donor nephrectomy.

The occurrence of renal cell carcinoma in the solitary remnant kidney after donor nephrectomy is rare and, to our knowledge, has not been previously reported. We encountered 2 such patients in whom cancer occurred 19 and 40 years after the donation. Both patients underwent successful partial nephrectomy for the tumor using two different techniques.

Carcinoma, Renal Cell↗
PubMed2004

Benign brain tumours and psychiatric morbidity: a 5-years retrospective data analysis.

OBJECTIVE: To examine the psychiatric comorbidity in benign brain tumours. METHOD: A retrospective (5 years) data analysis at our 500 bed teaching hospital. The diagnoses of benign brain tumours were based on the record of final diagnoses in the case records confirmed by either CT or MRI scans. Case records of patients with clearly documented history of psychiatric symptoms of several weeks to several months duration were identified only if such symptoms had antedated a diagnosis of the brain tumour. Using a specially designed proforma, two psychiatrists rated the symptoms together. We also collected data on age, gender and CT/MRI findings. Consensus was reached on all cases in regard to the psychiatric phenomenology. The symptoms were divided according to their presentation into purely neurological or psychiatric symptoms. RESULTS: A total of 79 patients were identified as having a primary diagnosis of benign brain tumour. There were 56 female patients and 23 male patients. Seventy-two of these had meningiomas. Fifteen (21%) of 72 meningioma cases, eight men and seven women, presented with psychiatric symptoms in the absence of neurological symptoms. Affective disorders were a common presentation. There was no correlation between brain laterality and the psychiatric comorbidity. CONCLUSIONS: Psychiatric symptoms may be the only initial manifestations of meningiomas of the brain in a significant number of cases occurring in the fifth decade of life. Such patients must be investigated by brain imaging studies even if there are no neurological signs or symptoms.

Adult↗
PubMed2004

Should retroperitoneoscopic nephrectomy be the standard of care for benign nonfunctioning kidneys? An outcome analysis based on experience with 449 cases in a 5-year period.

PURPOSE: Laparoscopic nephrectomy has become a routine procedure at specialized centers with the advantages of less postoperative pain, minimal scars, rapid recovery and short convalescence. We report our experience with the establishment of retroperitoneoscopic nephrectomy as the standard of care for benign nonfunctioning kidneys. MATERIALS AND METHODS: We retrospectively compared the records of patients who underwent simple nephrectomy retroperitoneoscopically or by open surgery from January 1998 to October 2003 at our center. RESULTS: A total of 351 simple nephrectomies were done retroperitoneoscopically, while 83 were done as an open procedure. Mean operative time was significantly longer in the retroperitoneoscopic group. However, mean blood loss, complication rate, hospital stay and convalescence were significantly less in the retroperitoneoscopic group. CONCLUSIONS: Retroperitoneoscopic nephrectomy has become a standardized procedure. It should be offered as the primary treatment modality to patients with benign renal disease scheduled for elective nephrectomy except in those in whom it is contraindicated.

Blood Loss, Surgical↗
PubMed2004

Complications of laparoscopic radical cystectomy during the initial experience.

AIM: Radical cystectomy is the standard of care for patients with muscle invasive bladder cancer. While open radical cystectomy is now a standard procedure, laparoscopic radical cystectomy is still in its infancy. We performed this surgery laparoscopically in 11 patients and review the procedure specific complications. METHODS: Beginning in February 1999, 11 patients underwent laparoscopic radical cystectomy at the Department of Urology, All India Institute of Medical Sciences, New Dehli. Urinary diversion was performed by an open-hand sewn ileal conduit. RESULTS: There were three intraoperative complications specifically related to the laparoscopic radical cystectomy. These included injury to the external iliac vein in one patient and a small rectal tear in two. All were repaired with laparoscopic free hand suturing with normal postoperative recovery. Other laparoscopy-related complications were subcutaneous emphysema in one patient and hypercarbia necessitating conversion to open surgery in a patient who, four weeks after surgery, died of multiple organ failure. One patient had margins positive and received cisplatinum-based chemotherapy. All patients had normal renal function and preserved upper tracts with no evidence of metastasis at a mean of 18.4 months follow up (range 1-48 months). CONCLUSIONS: Though there were three complications specific to the laparoscopic radical cystectomy, none necessitated a conversion to open surgery or hampered the overall outcome. Absence of local recurrence or metastatic disease at four years of follow up suggests that the procedure is oncologically valid. Laparoscopic radical cystectomy is a new procedure and it is important to critically analyze the complications in order to reduce their occurrence and allow the development of a better technique.

Adult↗