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N C Gupta

Publications and source records attributed to N C Gupta.

At least 19 recordsLinked to original sources
PubMed2004

Liquid chromatographic determination of amodiaquine in human plasma.

A normal-phase high-performance liquid chromatographic method using dichloromethane- methanol-1M perchloric acid (100:10:0.9, v/v/v) at a flow rate of 1.0 ml min(-1) on a LiChrospher Si column with UV (254 nm) detection has been developed for the determination of amodiaquine and its metabolites desethyl amodiaquine and bisdesethyl amodiaquine in plasma. The limit of quantification was 5 ng ml(-1). Mean within-day and day-to-day coefficients of variation (CV) were 4.10 and 6.27% for amodiaquine, 3.43 and 4.80% for desethyl amodiaquine and 3.53 and 5.23% for bisdesethyl amodiaquine, respectively. Mean extraction recovery of amodiaquine, desethyl amodiaquine and bisdesethyl amodiaquine from plasma were 82.48, 74.50 and 69.65%, respectively. Chloroquine and its metabolite desethyl chloroquine, quinine, sulfadoxine and primaquine do not interfere in the detection of amodiaquine, desethyl amodiaquine and bisdesethyl amodiaquine in plasma.

Amodiaquine↗
PubMed2003

Multi-drug resistant Plasmodium falciparum malaria in Assam, India: timing of recurrence and anti-malarial drug concentrations in whole blood.

The susceptibility of 23 cases of Plasmodium falciparum malaria from the Sonapur primary health center in the Kamrup district of Assam, India to different antimalarials was investigated using the 28-day World Health Organization in vivo test. Whole blood concentrations of chloroquine, sulfadoxine, and quinine were determined at different intervals and at the time of parasites recrudescence after completion of treatment with the respective drugs to confirm the status of drug sensitivity. A case of multi-drug resistant P. falciparum malaria was found where recrudescence occurred, despite standard oral treatment with chloroquine, sulfadoxine/pyrimethamine, and quinine sequentially. Whole blood concentrations of chloroquine, sulfadoxine, and quinine at the time of recrudescence were 0.35 microg/ml (day 7), 18 microg/ml (day 14), and 0.009 microg/ml (day 14), respectively. Therefore, monitoring of drug-resistant P. falciparum malaria and its proper treatment should be intensified to check the spread of multi-drug resistant strains in other parts of the country.

Adolescent↗
PubMed2001

Mediastinal lymph node sampling following positron emission tomography with fluorodeoxyglucose imaging in lung cancer staging.

OBJECTIVES: To evaluate the predictive accuracy as well as the rates of false-positive and false-negative results of CT and positron emission tomography (PET)-fluorodeoxyglucose (FDG) imaging in detecting the metastatic intrathoracic lymph nodes in patients with suspected or proven non-small cell lung cancer (NSCLC). Our other objective was to determine the need for routine invasive sampling procedure in confirming PET/CT staging results. METHODS: The results of CT and PET-FDG scanning in 77 patients with suspected or proven NSCLC were correlated with the histologic findings of hilar/mediastinal lymph node sampling using mediastinoscopy, open biopsy, thoracotomy, or thoracotomy with resection. Patients were then classified into resectable and unresectable groups based initially on PET results and compared to histologic findings. RESULTS: The sensitivity, specificity, and accuracy of CT and PET for detecting metastatic lymphadenopathy were 68%, 61%, 63%, and 87%, 91%, and 82%, respectively. A change of management with routine sampling following PET was seen in five of six patients (83%) with false-positive findings (13%) but in none of four patients (9%) with false-negative findings. CONCLUSION: The false-positive findings of PET-FDG imaging affected selection of treatment in 83% of patients. However, false-negative results did not change management in any patient. This could potentially prevent unnecessary invasive thoracotomy, mediastinoscopy, or other sampling procedures in patients with negative PET results.

Carcinoma, Non-Small-Cell Lung↗
PubMed2001

Clinical utility of PET-FDG imaging in differentiation of benign from malignant adrenal masses in lung cancer.

This study was designed to evaluate the sensitivity, specificity, and predictive accuracy of PET-FDG imaging in detecting metastatic disease involvement of adrenal glands in patients with lung cancer. We wanted to compare efficacy of positron emission tomography (PET)-fluorodeoxyglucose (FDG) imaging to computed tomography (CT) scanning in differentiating benign from malignant involvement of adrenal glands in patients with lung cancer. Thirty patients with biopsy-proven lung cancer and abnormal findings on PET and/or CT scanning were studied for presence of adrenal abnormality suggestive of metastatic disease involvement (n = 26) or benign adrenal enlargement (n = 4). The results of PET and CT scanning were compared to histological findings and/or clinical follow-up for at least 1 year for presence or absence of adrenal metastases. PET-FDG imaging correctly detected the presence of metastatic involvement in 17 of 18 patients and excluded metastatic involvement in 11 of 12 patients for sensitivity, specificity, and accuracy of 94.4%, 91.6%, and 93.3%, respectively. CT scanning showed enlarged adrenals without metastases in 8 of 30 patients and normal-sized adrenals in the presence of metastases in 5 of 30 patients. There was a false-positive PET finding in 1 patient and a false-negative PET finding in another patient. PET-FDG imaging is a highly sensitive, specific, and accurate test to differentiate benign from malignant involvement of adrenal glands in patients with lung cancer and often ambiguous findings on CT scanning.

Journal Article↗
PubMed2000

Chloroquine and desethylchloroquine concentrations in blood cells and plasma from Indian patients infected with sensitive or resistant Plasmodium falciparum.

The sensitivities of 61 Indian cases of Plasmodium falciparum malaria to chloroquine (CQ) were investigated using in-vitro and in-vivo methods. Concentrations of CQ and desethylchloroquine (DCQ) in blood cells and plasma from CQ-sensitive and -resistant cases were determined 2 and 7 days after initiation of treatment, by HPLC. On day 2, the mean CQ concentrations in the samples collected from the sensitive cases were higher than those in the samples from the resistant patients, in plasma (0.47 v. 0.32 microgram/ml; P < 0.02) and particularly in the blood cells (1.51 v. 0.46 micrograms/ml; P < 0.001). By day 7, however, the CQ concentrations in the two groups were similar. Although, on day 2, the mean ratio of the CQ to DCQ concentrations was significantly higher in the blood cells from the sensitive group than in those from the resistant cases (P < 0.01), the CQ/DCQ ratios for the plasma were similar for the two groups. Similarly, the mean ratio between the blood-cell concentration of CQ on day 2 and the concurrent plasma concentration (BPr) was also relatively high in the sensitive group (P < 0.001).

Adult↗
PubMed2000

Comparative efficacy of positron emission tomography with fluorodeoxyglucose in evaluation of small (<1 cm), intermediate (1 to 3 cm), and large (>3 cm) lymph node lesions.

PURPOSE: Our objective was to determine if positron emission tomography (PET) with fluorodeoxyglucose (FDG; PET-FDG) imaging is equally efficacious in detection of metastases in small and large mediastinal lymph nodes as compared to CT scanning. MATERIALS AND METHODS: PET-FDG imaging, CT scanning, and histology results of sampled mediastinal lymph nodes were compared in 54 patients of total 118 patients studied. Efficacy of PET and CT was determined and compared in small (< 1 cm), intermediate (1 to 3 cm), and large (> 3 cm) mediastinal lesions. RESULTS: PET was accurate in 94% of patients in characterizing "N" disease as compared to 61% with CT. Overall, sensitivity, specificity, and accuracy of PET for staging mediastinal lymph nodes (n = 168 in 54 patients) was 96, 93, and 94%, as compared to 68, 65, and 66% with CT. Positive and negative predictive value of PET in detecting mediastinal adenopathy was 86% and 98%, as compared to 47% and 82% with CT, respectively. PET was also highly reliable and accurate for detecting lymph nodes < 1 cm, 1 to 3 cm, and > 3 cm in size with superior efficacy than CT. Sensitivity, specificity, and accuracy of PET for detecting malignancy in lymph node lesions < 1 cm in size was 97, 82, and 95%, respectively. CONCLUSION: PET-FDG imaging is equally reliable and accurate for detecting disease in small and large lymph node lesions in patients with suspected or proven lung cancer with better efficacy than CT.

Adult↗
PubMed2000

Treatment outcome of lung cancer patients as optimized by preoperative whole-body positron emission tomography fluorodeoxyglucose imaging.

Positron emission tomography (PET) fluorodeoxyglucose (FDG) imaging may be more accurate than computed tomography (CT) scanning for staging of lung cancer disease. In the present study, we evaluate whether whole-body PET-FDG imaging can accurately stratify lung cancer patients by stage and thus predict patient outcome. Forty-one consecutive patients underwent whole-body PET and CT scanning for preoperative staging, which was then confirmed by mediastinoscopy, thoracotomy, and/or other tests revealing distant metastases. The effect of PET on patient management was determined. PET was significantly more accurate than CT for staging of lung cancer (97.6% vs. 70.7%). One-year follow-up for survival rate and treatment response was also compared in different patient groups. PET accurately identified patients with resectable disease (Group A). Group B patients, with medically inoperable disease, and Group C patients, with unresectable advanced disease, had 100% and 53% incidence of adverse events (defined as recurrence, evidence of new disease, or death), respectively. Group A patients with resectable disease who underwent surgery showed the best patient outcome, with only 7% incidence of adverse events. In conclusion, whole-body PET can be useful in identifying a group of lung cancer patients with resectable disease most likely to benefit from surgical resection. Further studies are needed to explore whether PET can predict patient outcome of various lung cancer patients receiving different treatment regimens.

Journal Article↗
PubMed2000

Investigation of malaria prevalence at National Thermal Power Corporation, Shaktinagar, Sonbhadra District (Uttar Pradesh), India.

Malaria in industrial complexes is promoted by extensive mosquitogenic potential generated by excavations and importation of parasite through migratory labor. The National Thermal Power Corporation (NTPC), Shaktinagar, Sonbhadra district was surveyed for malariogenic conditions from 1994 to 1996. The major mosquito breeding sites were drains, storm-water drains, lakes, outside tanks, overhead tanks, sluice-valve chambers, ornamental tanks, wells, pit wells and water reservoirs, etc. Anopheles culicifacies was the major vector of malaria in this area. Sibling species identification of An. culicifacies revealed that species C predominated during the transmission season and responsible to transmit malaria. Insecticide susceptibility tests against An. culicifacies sl showed that An.culicifacies population was 100% susceptible to malathion, fenitrothorn and deltamethrin while it was found 44% resistant to DDT. The malaria cases recorded in 1994, 1995 and 1996 were 847, 590 and 409 respectively. In vitro study on P. falciparum cases showed that 41, 70, 50% of the isolates tested were resistant to chloroquine in 1994, 1995 and 1996 respectively while an in vivo follow-up study showed 20-30% P. falciparum cases resistant to chloroquine. An integrated approach involving alternate vector control measures along with judicious use of insecticides has been suggested to bring down malaria in industrial complexes.

Animals↗
PubMed1999

Positron emission tomographic imaging with fluorodeoxyglucose isefficacious in evaluating malignant pulmonary disease.

OBJECTIVE: Positron emission tomography (PET), when used with the intravenously administered radiopharmaceutical F-18 fluorodeoxyglucose (FDG), has the potential to help in the evaluation of patients with lung cancer because the radiopharmaceutical is concentrated by metabolically active cells. We conducted a retrospective study of PET-FDG in 96 patients evaluated at our institution over the past 2 years for suspected primary pulmonary neoplasms. PET-FDG results were compared with the findings of computed tomographic scans on the same patients. All patients underwent surgical exploration with or without resection of the malignant tumors. Sites of potential malignancy were subjected to biopsy and/or excision, with subsequent pathologic evaluation. RESULTS: A total of 96 patients with suspected or proven primary pulmonary malignant disease were evaluated. Sixty-six patients had histologically confirmed malignant tumors, and 30 had benign masses histologically. PET-FDG had an accuracy of detecting malignancy in pulmonary lesions of 92% (sensitivity 97%; specificity 89%). A total of 111 surgically sampled sites were from lymph nodes. PET-FDG was accurate in predicting the malignancy of nodes in 91% of instances, whereas computed tomography was correct in 64%. The sensitivity, specificity, and predictive accuracy of PET in detecting metastatic lymphadenopathy in mediastinal lymph nodes were 98%, 94%, and 95%, respectively. PET-FDG also changed the M stage in 8 (12%) patients (6 with and 2 without metastases). The 6 malignant (positive) lesions were correctly identified by PET-FDG, and the 2 without tumor were accurately predicted as benign (negative). CONCLUSION: These initial results suggest that PET-FDG is highly accurate in identifying and staging lung cancer. PET-FDG also appears to be more accurate in detecting metastatic mediastinal lymphadenopathy than computed tomographic scan.

Aged↗
PubMed1999

Comparative efficacy of positron emission tomography with FDG and computed tomographic scanning in preoperative staging of non-small cell lung cancer.

OBJECTIVE: To determine the sensitivity, specificity, and accuracy of positron emission tomography with 2-fluorine-18-fluorodeoxyglucose (PET-FDG) in the preoperative staging (N and M staging) of patients with lung cancer. The authors wanted to compare the efficacy of PET scanning with currently used computed tomography (CT) scanning. MATERIALS AND METHODS: Results of whole-body PET-FDG imaging and CT scans were compared with histologic findings for the presence or absence of lymph node disease or metastatic sites. Sampling of mediastinal lymph nodes was performed using mediastinoscopy or thoracotomy. RESULTS: PET-FDG imaging was significantly more sensitive, specific, and accurate for detecting N disease than CT. PET changed N staging in 35% and M staging in 11% of patients. CT scans helped in accurate anatomic localization of 6/57 PET lymph node abnormalities. CONCLUSION: PET-FDG is a reliable method for preoperative staging of patients with lung cancer and would help to optimize management of these patients. Accurate lymph node staging of lung cancer may be ideally performed by simultaneous review of PET and CT scans.

Adult↗
PubMed1999

FDG-PET in the staging work-up of patients with suspected intracranial metastatic tumors.

OBJECTIVE: To evaluate the role of positron emission tomography with 2-[18F] fluoro-2-deoxy-D-glucose (FDG-PET) in 31 patients with evidence of intracranial metastatic disease. MATERIALS AND METHODS: PET was used to evaluate the intracranial lesions for glucose hypermetabolism to suggest malignancy, mutiplicity of intracranial lesions, and extracranial foci or sources of disease. Patients with proven malignant intracranial lesions subsequently underwent further corroborative radiologic tests and histologic examination to confirm staging and primary location. RESULTS: PET identified focal hypermetabolic abnormalities in 19 of 22 intracranial metastases, 2 hypometabolic lesions, and 1 renal cell tumor embolism that hemorrhaged (hypometabolic lesion). It also identified 82% of extracranial primary tumor sites, of which 55% were found only on PET and not on conventional diagnostic tests. CONCLUSION: FDG-PET may prove valuable in the initial work-up of patients with suspected intracranial metastases.

Aged↗
PubMed1999

Chloroquine concentration profile in the community of Mewat region, district Gurgaon (Haryana), India.

A survey was conducted to find chloroquine concentration profile in the community of Mewat region district Gurgaon (Haryana) of India. 88 P. falciparum and 3 P. vivax cases were detected out of 148 blood slides examined with a SPR of 61.48. Plasma chloroquine and desethylchloroquine concentrations were determined in 55 P. falciparum and 2 P. vivax patients and 29 persons whose blood slides were negative for malaria parasite before giving any treatment. Mean chloroquine concentrations in cases with P. falciparum parasites and without malaria parasites were 0.018 and 0.016 microg ml(-1) respectively. Chloroquine to desethyl chloroquine ratio was between 2 and 3 in both groups. Only 10 malaria parasite negative cases out of 29 had plasma chloroquine concentrations above 0.016 microg ml(-1) required for malaria chemoprophylaxis. Chloroquine was undetectable in plasma samples of 8 out of 55 P. falciparum cases. Chloroquine plasma concentrations in 21 P. falciparum cases were below therapeutically effective concentration of 0.016 microg ml(-1) suggesting improper treatment while in 29 P. falciparum cases, parasitemia recurred despite required chloroquine concentration confirming chloroquine resistant status. Irregular prophylaxis and lack of proper treatment was one of the major causes of malaria outbreak in this area.

Adult↗
PubMed1998

Sulfalene concentrations in plasma and blood cells of Plasmodium falciparum malaria cases after treatment with metakelfin using high-performance liquid chromatography.

A reversed-phase high-performance liquid chromatographic method using acetonitrile-methanol-1 M perchloric acid-water (25:9:0.8:95, v/v/v) at a flow-rate of 1.0 ml min(-1) on LiChrospher 100 RP 18 column (250 x 4 mm; 5 microm) with UV (254 nm) detection has been developed for the determination of sulfalene in plasma and blood cells after oral administration of the antimalarial drug metakelfin. Calibration curves were linear in the range 0.5-100 microg ml(-1). The limit of quantification was 50 ng ml(-1). Within-day and day-to-day coefficients of variation averaged 3.84 and 5.31%, respectively. Mean extraction recoveries of sulfalene from plasma and blood cells were 87.21 and 84.65%, respectively. Mean concentrations of sulfalene in plasma of P. falciparum cases on days 2, 7 and 15 were 44.58, 14.90 and 1.70 microg ml(-1), respectively; in blood cells concentrations of sulfalene were 7.77, 3.25 and 0.75 microg ml(-1), respectively, after oral treatment with two tablets (1000 mg) of metakelfin. Significant difference was recorded on day 2 for sulfalene concentration in blood cells of healthy and P. falciparum cases (t=9.49; P<0.001).

Adult↗
PubMed1997

Assessing coronary artery disease with dipyridamole technetium-99m-tetrofosmin SPECT: a multicenter trial.

UNLABELLED: Exercise 99mTc-tetrofosmin myocardial scintigraphy is as accurate as exercise 201TI imaging. Thus far, no data are available on tetrofosmin imaging during pharmacologic stress. We evaluated the feasibility of using. 99mTc-tetrofosmin myocardial SPECT during vasodilation with dipyridamole for detecting coronary artery disease. METHODS: Sixty-four patients, enrolled in three centers in the U.S., underwent one-day dipyridamole/rest tetrofosmin SPECT. Coronary angiography, performed in 59 patients within 2 mo of the SPECT study, revealed normal coronary arteries or insignificant coronary stenosis in 11 patients and significant (> or = 50% luminal diameter stenosis) coronary stenoses in 48 patients. RESULTS: Sensitivity and specificity of tetrofosmin SPECT for detecting coronary artery disease were 85% and 55%, respectively, in the overall population and 81% and 55% in patients without prior coronary artery bypass surgery. The overall sensitivity and specificity of tetrofosmin tomographic imaging for detection of individual coronary stenoses were 53% and 72%, respectively, in the overall population and 54% and 80% in the patients without prior coronary artery bypass surgery. CONCLUSION: One-day dipyridamole/rest 99mTc-tetrofosmin myocardial perfusion imaging is feasible and has a high sensitivity for detection of coronary artery disease.

Adult↗
PubMed1997

In-vivo and in-vitro sensitivity of Plasmodium falciparum to chloroquine in Chennai (Tamil Nadu), India.

In-vitro and in-vivo susceptibility of Plasmodium falciparum to chloroquine were conducted at Chennai city, India. Eighteen (60%) out of 30 cases showed resistance in in-vitro study. EC50 of resistant and sensitive cases were 0.40 and 0.24 mumol chloroquine/l blood respectively, while EC90 were 2.64 and 0.84 mumol chloroquine/l blood respectively. In-vivo tests identified 24 cases (40%) as resistant (23 RI and 1 RII) and 36 (60%) as sensitive out of 60 cases. Eight isolates which were found resistant with in-vitro tests showed sensitive behaviour to chloroquine treatment assessed by in-vivo studies.

Adolescent↗
PubMed1996

Dependency of standardized uptake values of fluorine-18 fluorodeoxyglucose on body size: comparison of body surface area correction and lean body mass correction.

In an attempt to minimize dependency of conventional standardized uptake values (SUVs) of F-18-fluorodeoxyglucose (FDG) normalized for the total body weight (TBW) on patient's body weight, the uses of SUV corrected for the lean body mass (LBM) and that corrected for the body surface area (BSA) have been proposed as alternatives. We compared the dependency of SUVLBM and SUVBSA on the overall body size. FDG-PET images were acquired on 44 patients. SUVLBM and SUVBSA for the liver were determined as previously described. Following normalization of the scales of the values obtained from these two approaches, the mean +/- S.D. was 2.86 +/- 0.52 (SUVLBM) and 2.86 +/- 0.50 (SUVBSA). A linear regression analysis was performed for correlating the liver SUVLBM and SUVBSA, with each of TBW, LBM, BSA and height. The dependency of the two values on TBW was similar. SUVLBM showed a moderate dependency on height (r = 0.56, P = 0.00007), LBM (r = 0.55, P = 0.0001) and BSA (r = 0.51, P = 0.0004), whereas SUVBSA showed no dependency on LBM (r = 0.18, P = 0.24) or height (r = 0.20, P = 0.19), and a minimal dependency on BSA (r = 0.38, P = 0.01). In conclusion, SUVBSA appears to be less dependent on overall body size, particularly height and lean body mass, than SUVLBM.

Abdominal Neoplasms↗
PubMed1996

Probability of malignancy in solitary pulmonary nodules using fluorine-18-FDG and PET.

UNLABELLED: Nearly one-third of solitary pulmonary nodules are radiographically indeterminate for the presence of malignancy. METHODS: FDG-PET imaging was used to differentiate benign and malignant solitary pulmonary nodules in 61 patients with radiographically indeterminate nodules. After confirmation of the histological diagnosis, the probability for cancer was established for positive and negative PET scans and compared to the risk estimates calculated using other patient variables. RESULTS: FDG-PET had a sensitivity, specificity and positive predictive value of 93%, 88% and 92%, respectively, for detecting malignancy in indeterminate solitary pulmonary nodules. The probability of malignancy with a positive PET scan is 83%, which increases with the patient's age (90% in >60 yr) and the size of the nodule. A negative PET scan is associated with only a 4.7% risk of malignancy. FDG-PET also accurately characterized hilar/mediastinal lymphadenopathy in 12 patients with associated lymph node lesions. CONCLUSION: FDG-PET imaging can be a useful noninvasive test to determine the risk estimate or probability of cancer as well as preoperative staging in patients with radiographically indeterminate solitary pulmonary nodules.

Adult↗