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Sunil Kumar

Publications and source records attributed to Sunil Kumar.

At least 55 records · Page 3Linked to original sources
PubMed2004

Interleukin-1beta modulates state-dependent discharge activity of preoptic area and basal forebrain neurons: role in sleep regulation.

Interleukin-1beta (IL-1) is a pro-inflammatory cytokine that has been implicated in the regulation of nonrapid eye movement (nonREM) sleep. IL-1, IL-1 receptors and the IL-1 receptor antagonist (ra) are present normally in discrete brain regions, including the preoptic area (POA) of the hypothalamus and the adjoining magnocellular basal forebrain (BF). The POA/BF have been implicated in the regulation of sleep-wakefulness. We hypothesized that IL-1 promotes nonREM sleep, in part by altering the state-dependent discharge activity of POA/BF neurons. We recorded the sleep-wake discharge profiles of 83 neurons in the lateral POA/BF and assessed the effects of IL-1, IL-1ra, and IL-ra + IL-1 delivered through a microdialysis probe on state-dependent neuronal discharge activity. IL-1 decreased the discharge rate of POA/BF neurons as a group (n = 55) but wake-related and sleep-related neurons responded differently. IL-1 significantly decreased the discharge rate of wake-related neurons. Of 24 wake-related neurons studied, 19 (79%) neurons exhibited a greater than 20% change in their discharge in the presence of IL-1 during waking. IL-1 suppressed the discharge activity of 18 of 19 responsive neurons. Of 13 sleep-related neurons studied, IL-1 increased the discharge activity of five and suppressed the discharge activity of four neurons. IL-1ra increased the discharge activity of four of nine neurons and significantly attenuated IL-1-induced effects on neuronal activity of POA/BF neurons (n = 19). These results suggest that the sleep-promoting effects of IL-1 may be mediated, in part, via the suppression of wake-related neurons and the activation of a subpopulation of sleep-related neurons in the POA/BF.

Action Potentials↗
PubMed2004

Occupational exposure associated with reproductive dysfunction.

Evidence suggestive of harmful effects of occupational exposure on the reproductive system and related outcomes has gradually accumulated in recent decades, and is further compounded by persistent environmental endocrine disruptive chemicals. These chemicals have been found to interfere with the function of the endocrine system, which is responsible for growth, sexual development and many other essential physiological functions. A number of occupations are being reported to be associated with reproductive dysfunction in males as well as in females. Generally, occupations involving the manufacture/or application of some of the persistent chemicals that are not easily degradable as well as bio-accumulative chemicals, occupations involving intensive exposure to heat and radiation, occupations involving the use of toxic solvents as well as toxic fumes are reported to be associated with reproductive dysfunction. Occupational exposure of males to various persistent chemicals have been reported to have male mediated adverse reproductive outcomes in the form of abortion, reduction in fertility etc. with inconclusive or limited evidence. Nevertheless, there is a need for more well designed studies in order to implicate any individual chemical having such effects as in most occupations workers are exposed to raw, intermediate and finished products and there are also several confounding factors associated with lifestyles responsible for reproductive dysfunction. There is an urgent need to look at indiscriminate use of persistent chemicals especially pesticides and persistent organic pollutants (POP's) as these chemicals enter the food chain also and could be potential for exposure during the critical period of development. It is also necessary to impart information, and to educate about the safe use of these chemicals, as a very sensitive reproduction issue is involved with exposure to these chemicals. Occupational exposures often are higher than environmental exposures, so that epidemiological studies should be conducted on these chemicals, on a priority basis, which are reported to have adverse effects on reproduction in the experimental system.

Agricultural Workers' Diseases↗
PubMed2004

Development of indigenous local exhaust ventilation system: reduction of welders exposure to welding fumes.

Two (portable and mobile) local exhaust ventilation (LEV) units were developed in collaboration with the Rural Technology Institute, Gandhinagar, India. Basically, each unit consists of three parts comprising an electric motor, a blower and a fume hood. In both units the motor is fixed in a rectangular iron frame in a foot-mount position and equipped compactly with a blower, which in turn is connected to a fume hood through a flexible hosepipe. The portable unit is light in weight (50 kg) and has a cone shaped metallic fume hood. The mobile unit, on the other hand, differs from the portable model with respect to its weight (150 kg), size, RPM, voltage requirement, hood shape and size, and has a motor enclosure. The efficiency of the portable and mobile units on trial bases was tested by measuring the manganese concentration as a reference metal in welding fumes generated by electric arc welding. The concentration of manganese (mean +/- SD) was 0.218 +/- 0.06 microg/m3 in the general environment. In the workplace area where joining of metal objects by welding was done, the concentration of manganese was found to be 0.63 +/- 0.09 and 3.75 +/- 0.56 microg/m3 at a distance of 5 m and 2 m away from the site of operation, respectively. In the breathing zone it was 22.16 +/- 20.90 microg/m3 which was reduced to 8.25 +/- 4.5 microg /m3 after application of a portable LEV showing about 63% removal of the manganese concentration from the breathing zone of the welder. In another experiment conducted with a mobile LEV unit for heavy-duty work, the concentration of manganese in the breathing zone without operating the mobile LEV was 70.06 +/- 37.38 microg /m3 but was lowered to 8.29 +/- 1.76 microg /m3 after operating the mobile LEV. This indicated an average removal of manganese content by about 88% from the breathing zone of the welder. In both the experiments locations of sample collection were similar.

Air↗
PubMed2004

Assessment of quality of handwritten discharge tickets of breast cancer patients: the gaps are wide and need remedy.

BACKGROUND: Discharge tickets (DTs) convey important details related to hospitalization period and follow-up instructions. Therefore, quality of DTs may have significant bearing on subsequent patient care. AIMS, SETTING AND DESIGN: Aim of this retrospective study was to assess quality of handwritten DTs of breast cancer patients admitted at this institution. METHODS AND MATERIAL: DTs of 736 breast cancer patients were evaluated on six predetermined quality parameters by verifying entries from their respective case sheets drawn from the medical record department of this institution. These parameters included sections of discharge tickets dealing with central registration (CR) number, tumor stage, in-hospital treatment details, instructions for subsequent treatment and instructions regarding surgical wound care were evaluated for accuracy and clarity. General legibility was also assessed. The audit was done by the author. RESULTS: Almost all DTs were found to be legible and accurate for CR number. In-hospital treatment details were entered accurately in 98%. Tumor stage was correctly indicated in 57.5%. Follow-up and wound-care instructions were written clearly in 76.5% and 53.9% DTs, respectively. CONCLUSIONS: Handwritten DTs of breast cancer patients at this institution were satisfactory for three, but deficient for three other important quality parameters. These findings suggest that there is an acute need to review practice of preparing handwritten DTs in order to provide good quality of subsequent care.

Breast Neoplasms↗
PubMed2003

Arsenic reduction from aqueous environment by water lettuce (Pistia stratiotes L.).

Arsenate uptake by aquatic plant water lettuce (Pistia stratiotes L.) was studied in the laboratory condition to investigate a low cost natural aquatic treatment system for pollutant removal. The plants were harvested from a local pollution free pond in young condition and hydroponically cultured in the laboratory. Bioaccumulation was noticed to be both concentration and duration dependent. The results show that the plant could effectively abosrb arsenic between a range of 0.25 to 5.0 mg/l to the extent of 82.0 to 22.8% for a biomass of 20g/l at pH 7.0 after 144 hours. The results were also plotted in Langmuir and Freundlich isotherms and the data were well fitted. The sorption capacity was evaluated as 1.43 mg/g for Langmuir isotherm and 1.01 mg/g for Freundlich isotherm. The removal efficiency was, however, noted to be maximum (87.5%) at pH 6.5. The effect of biomass quantity has also been investigated along with some metabolic parameters.

Adsorption↗
PubMed2002

A survey of indications, results and complications of surgery for tophaceous gout.

AIMS: To document the indications, results and complications associated with surgery for tophaceous gout in Middlemore Hospital. METHODS: A retrospective study of the notes of all patients who underwent surgery for tophaceous gout at Middlemore Hospital from July 1995 to July 2001 was performed. Serum creatinine and uric acid results were obtained and the use of allopurinol assessed. RESULTS: 45 patients underwent surgery for gouty tophi. 89% were males and 11% females. 16% were Maori, 38% Pacific people, 42% Europeans and 4% were from other ethnic backgrounds. Renal impairment (serum creatinine. >0.11 mmol/L) was the most common associated medical problem (38%), followed by hypertension (27%), ischaemic heart disease and/or congestive heart disease (20%) and diabetes mellitus (18%). 68% of patients had elevated serum urate levels (>0.42 mmol/L) and only 31% had previously been taking allopurinol. Sepsis control in infected or ulcerated tophi was the main indication for surgery (51%), followed by mechanical problems caused by foot, elbow and hand tophi (27%). The diagnosis of soft tissue masses was unclear in 18% of the patients prior to surgery. 4% of patients underwent tophus surgery mainly for pain control. 53% of patients experienced delayed wound healing as a result of complications of surgery with the majority of these patients (16/24, 67%) having infected or ulcerated tophi prior to surgery. Three patients (7%) required digital amputations for ongoing sepsis. 47% of patients did not have any complication of surgery and had complete wound healing within one week. CONCLUSIONS: Surgery for tophaceous gout is associated with a relatively high rate of complication when sepsis is the main indication. Patients with gout in this study population had several associated medical co-morbidities, which contributed to the high complication rate. Gout control was poor as evidenced by a high rate of hyperuricaemia, and less than one third of the study population were on allopurinol. Better control of gout would reduce the risk of tophi formation and the need for surgery.

Adult↗
PubMed2001

Similarities and differences of MR findings between Japanese encephalitis and Wilson's disease.

Although Japanese Encephalitis (JE) and Wilson's disease (WD) are different entities, MR findings in both these conditions are quite similar. The purpose of this retrospective study was to find out the similarities and differences between JE and WD on MR imaging. The study group comprised 25 proven cases of JE and 10 cases of WD. Spin echo (SE) TI- and T2-weighted imaging was performed on a 1.5-T MR system. Fourteen of these 35 cases (10 JE, 4 WD) were also examined using T1-weighted magnetization transfer (MT) SE sequence before and after contrast administration. Although both JE and WD showed similar topographical distribution of lesions, predominant involvement of the basal ganglia and thalami, there were some differences. Brain stem lesion was more frequent for WD than for JE, and posteromedial part of the thalami was spared in WD. The lesion characteristics were also different between both; in WD mixed intensity in the basal ganglia and hyperintense linear rim at the peripheral putamen was observed frequently, whereas hyperintense basal ganglia on T2-weighted images, subacute hemorrhage in the thalami and meningeal enhancement were seen only in the patients with JE. These characteristic lesion criteria may help in differentiation of JE from WD on MR imaging.

Adult↗
PubMedDate not supplied

Diffusion-weighted MR imaging in Japanese encephalitis.

OBJECTIVE: This study was performed to evaluate the role of diffusion-weighted imaging (DWI) in the diagnosis of Japanese encephalitis (JE) and to look for any relationship of the apparent diffusion coefficient (ADC) values with duration of the illness. METHODS: We performed DWI in fourteen patients of JE. T2 weighted (T2W) and DWI were compared for number and location of lesions in all patients. Based on imaging patients were divided in three groups: group 1 (n=9) showing more lesions on DWI compared with T2W images, group 2 (n=3) with equal number of lesions on T2W and DWI and group 3 (n=2) with lesions more pronounced on T2W than DWI. ADC values were computed for all the lesions. The time interval between onset of neurologic signs/symptoms and MRI were charted and correlated with ADC values. RESULTS: DWI was helpful in making early diagnosis of JE by showing characteristic involvement of bilateral thalami in four patients. Nine out of fourteen patients showed additional lesions on DWI. ADC from lesions in groups I, II and III measured 0.648 +/- 0.099 x 10 mm/s, 0.739 +/- 0.166 x 10 mm/s and 1.123 +/- 0.185 x 10 mm/s respectively. The ADC from the lesions in group 1 was significantly lower compared with group 2 (P value <0.05) while it was higher in group 3 lesions compared with the other two groups. There was a significant direct correlation of ADC values with the disease duration in these cases (r=0.847, P <0.01). CONCLUSIONS: DWI is helpful in early diagnosis and characterization of the duration of the lesions in JE.

Adolescent↗
PubMedDate not supplied

Surgical management of skin cancers: experience from a regional cancer centre in North India.

AIMS: To review the disease profile and treatment outcome of patients with primary skin malignancies treated at a regional cancer centre. SETTINGS AND DESIGN: Surgical oncology unit of a tertiary care regional cancer centre. Evaluation of treatment outcome of patients with skin cancer from Surgical Oncology database was done. MATERIALS AND METHODS: Retrospective analysis of records of 77 patients with skin cancers treated between 1995 and 2002 was conducted. Profile of patients with skin cancer, surgical details including the management of primary tumour, regional lymph nodes and reconstructive procedures performed and survivals were analysed. STATISTICAL ANALYSIS: All computations were done using the Statistical Package for Social Sciences (SPSS-9). Descriptive statistics were calculated in a standard fashion and survival analysis was performed using Kaplan-Meier method. RESULTS: Skin cancers constituted 2.4% (77/3154) of patients with cancer treated in the surgical oncology department. Squamous cell carcinoma (SCC) was the most common histological type (55.8%) followed by melanoma (26.1%) and basal cell carcinoma (BCC, 18.1%). Forty one percent of patients had undergone some form of intervention elsewhere before being referred. Reconstruction was required in 55.8% patients with large postresection defects. Regional lymph nodal dissection was required in 32.4% of total patients. Five-year median disease-free survival for the entire study population was 75%. CONCLUSIONS: Skin cancers constitute a small but significant proportion of patients with cancer. Unlike in the Western countries, SCC is the commonest histologic variety. Primary level inadequate intervention is very common. Optimal results can be obtained with radical surgery and optimal surgical margins along with a reconstructive procedure when needed.

Adolescent↗
PubMedDate not supplied

Clinicopathological features in 102 cases of Hirschsprung disease.

BACKGROUND: Hirschsprung disease [HD] is a predominantly childhood disorder of intestinal motility with a multifactorial and polygenic etiology. The objective of this study was to document the clinical and pathological features of HD in Kuwait, which has an estimated consanguinity rate of 54%. METHODS: We analyzed all rectal and colonic biopsies (n=268) for suspected HD identified from the records in the Pathology Department of Al-Sabah Hospital for the period between 1994 and 2004. RESULTS: One hundred and two patients (87 males and 15 females) had histologically confirmed HD. Fifty-eight (57%) were neonates (<1 month of age), while 21% were more than 4 months old. The diagnosis was based on open biopsy in 11 cases and rectal biopsies in 91 cases. Nine patients with open biopsies presented as intestinal obstruction, necrotizing enterocolitis, or perforation. The extent of the disease was unknown in 13 patients. There were 67 males and 3 females with short segment HD. Nine had long segment, two ultra-short segment and eight total colonic aganglionosis (TCA). Five TCA cases involved the small intestine. A skip area was observed in two cases. Six patients had other anomalies. A positive family history for HD was established in three patients. Two of these were male siblings from a consanguineous marriage and had Waardenburg syndrome. CONCLUSION: This study has highlighted an exceptionally strong male predominance of short segment and a relatively high frequency (5.6%) of small intestinal involvement in HD in Kuwait. These data call for a more detailed epidemiological study with special emphasis on genetics.

Adolescent↗
PubMedDate not supplied

Carotid artery stenting with filter protection.

BACKGROUND: Neurologic events associated with distal embolization of debris during percutaneous carotid artery stenting complicate the procedure. Filter devices for cerebral protection potentially reduce the risk of embolization and other neurologic events. We studied the feasibility, safety, and efficacy of carotid artery stenting with a filter device. METHODS AND RESULTS: Between January 2002 and January 2003, a total of 22 consecutive patients (30 lesions) who had >70% diameter stenosis of the internal carotid artery underwent carotid artery stenting with filter protection at our institute. The mean age of the patients was 64+/-9 years; 14 were men and 8 women, and 15 had neurologic symptoms. A stent was successfully implanted in 29 lesions. It was possible to position a filter device in all the 29 lesions. Neurologic complications during the procedure, in the hospital, and at 30-day clinical follow-up occurred in 2 patients. One patient suffered a minor stroke that resolved within 24 hours. None of the patients had a major embolic stroke. There was one death from intracerebral hemorrhage related to hyperperfusion and the use of a glycoprotein IIb/IIIa inhibitor. CONCLUSIONS: Filter protection during carotid artery stenting seems technically feasible, safe, and effective. In the present study, the incidence of embolic neurologic events was low.

Aged↗
PubMedDate not supplied

Patient profile and treatment outcome of rectal cancer patients treated with multimodality therapy at a regional cancer center.

BACKGROUND: Incidence of rectal cancer has wide geographical variation. Disease pattern in developing countries is different from developed countries as majority of the patients present in advanced stage because of delayed referral and lack of uniform treatment practices. AIMS: Present study describes the patient profile and treatment results from a tertiary care cancer center in India. SETTING AND DESIGN: Tertiary care Regional cancer center. Retrospective analysis 89 patients with rectal adenocarcinoma treated between 1995 and 2002 were analyzed. METHODS: Patients with adenocarcinoma rectum were evaluated in a G.I. Oncology clinic and were treated using multimodality protocols involving surgery, radiotherapy and adjuvant chemotherapy. STATISTICAL ANALYSIS: A descriptive analysis of patient and disease profile, treatment patterns and out come was performed. Survival analysis was performed using Kaplan-Meier method. RESULTS: Mean age of the patients was 45.4 years and majority of them had tumor in lower third of rectum with evidence of extrarectal spread. Seventy five percent of the patients underwent curative resection with abdominoperineal resection being the commonest procedure. Forty seven percent of patients were given short course preoperative radiotherapy and the remaining received postoperative radiotherapy. Sixty four percent of patients could complete planned adjuvant chemotherapy. Operative mortality was 2% and 23% had morbidity. Local recurrence rate was 8.9%. 5-year disease free and overall survival was 54% and 58% respectively. CONCLUSION: Majority of rectal cancer patients present with locally advanced and low rectal growths leading to low sphincter salvage rates. Despite the advanced stage of presentation optimal oncologic results can be obtained by using a good surgical techniques in combination with adjuvant radiotherapy and chemotherapy. Short course preoperative radiotherapy seems to be more feasible in Indian context. Timely referral and uniform treatment guidelines throughout the country are needed for optimal management of rectal cancer in India.

Adenocarcinoma↗