Search PubMed⌕ Search

Biomedical subjects

R K Gupta

Publications and source records attributed to R K Gupta.

At least 145 records · Page 8Linked to original sources
PubMed2000

Risk of second malignancy after Hodgkin's disease in a collaborative British cohort: the relation to age at treatment.

PURPOSE: To assess long-term site-specific risks of second malignancy after Hodgkin's disease in relation to age at treatment and other factors. PATIENTS AND METHODS: A cohort of 5,519 British patients with Hodgkin's disease treated during 1963 through 1993 was assembled and followed-up for second malignancy and mortality. Follow-up was 97% complete. RESULTS: Three hundred twenty-two second malignancies occurred. Relative risks of gastrointestinal, lung, breast, and bone and soft tissue cancers, and of leukemia, increased significantly with younger age at first treatment. Absolute excess risks and cumulative risks of solid cancers and leukemia, however, were greater at older ages than at younger ages. Gastrointestinal cancer risk was greatest after mixed-modality treatment (relative risk [RR] = 3.3; 95% confidence interval [CI], 2.1 to 4.8); lung cancer risks were significantly increased after chemotherapy (RR = 3. 3; 95% CI, 2.4 to 4.7), mixed-modality treatment (RR = 4.3; 95% CI, 2.9 to 6.2), and radiotherapy (RR = 2.9; 95% CI, 1.9 to 4.1); breast cancer risk was increased only after radiotherapy without chemotherapy (RR = 2.5; 95% CI, 1.4 to 4.0); and leukemia risk was significantly increased after chemotherapy (RR = 31.6; 95% CI, 19.7 to 47.6) and mixed-modality treatment (RR = 38.1; 95% CI, 24.6 to 55. 9). These risks were generally greater after treatment at younger ages: for patients treated at ages younger than 25 years, there were RRs of 18.7 (95% CI, 5.8 to 43.5) for gastrointestinal cancer after mixed-modality treatment, 14.4 (95% CI, 5.7 to 29.3) for breast cancer after radiotherapy, and 85.2 (95% CI, 45.3 to 145.7) for leukemia after chemotherapy (with or without radiotherapy). CONCLUSION: Age at treatment has a major effect on risk of second malignancy after Hodgkin's disease. Although absolute excess risks are greater for older patients, RRs of several important malignancies are much greater for patients who are treated when young. The increased risk of gastrointestinal cancers may relate particularly to mixed-modality treatment, and that of lung cancer to chemotherapy as well as radiotherapy; there are also well-known increased risks of breast cancer from radiotherapy and leukemia from chemotherapy. The roles of specific chemotherapeutic agents in the etiology of solid cancers after Hodgkin's disease require detailed investigation.

Adolescent↗
PubMed2000

High-dose therapy with autologous bone marrow support as consolidation of remission in follicular lymphoma: long-term clinical and molecular follow-up.

PURPOSE: To evaluate the long-term results of high-dose therapy (HDT) in follicular lymphoma, with specific emphasis on the prognostic significance of polymerase chain reaction (PCR)-detectable Bcl-2/IgH rearrangements. PATIENTS AND METHODS: Between June 1985 and October 1995, 99 patients with follicular lymphoma received HDT as consolidation of second or subsequent remission. Bone marrow was treated in vitro with anti-B-cell antibodies and complement. RESULTS: Sixty-five patients remained alive, 49 treatment-failure free, with a median follow-up of 5.5 years (range, 1.5 to 12.5 years). Four "early" and 10 "late" deaths occurred from treatment-related causes; seven of the latter were due to secondary myelodysplasia (s-MDS) or secondary acute myeloblastic leukemia. Overall, 12 (12%) of the 99 patients developed s-MDS or acute myeloblastic leukemia. Kaplan-Meier estimates of freedom from recurrence (FFR) and survival rates at 5 years were 63% (95% confidence interval [CI], 52% to 72%) and 69% (95% CI, 58% to 78%), respectively. For all 99 patients, in multivariate analysis, absence of the Bcl-2/IgH rearrangement at the time of diagnosis (hazards ratio [HR], 0.39; P =.04) and three or fewer treatment episodes before HDT (HR, 0.03; P =.001) were significant prognostic factors for improved survival. For patients bearing Bcl-2/IgH rearrangements, in univariate and multivariate analyses, absence of a PCR-detectable Bcl-2/IgH rearrangement during follow-up was associated with a significantly lower risk of recurrence (adjusted HR, 0.13; P <.001) and death (HR, 0.25; P =.02), whereas the PCR status of the reinfused bone marrow did not correlate with outcome. CONCLUSION: Prolonged FFR can be achieved in patients with follicular lymphoma after HDT, but as yet there is no survival advantage compared with conventional treatment. These results confirm that elimination of cells bearing the Bcl-2/IgH rearrangement is highly desirable and should be attempted. The incidence of s-MDS is of increasing concern in this setting.

Adult↗
PubMed2000

Perilesional gliosis and seizure outcome: a study based on magnetization transfer magnetic resonance imaging in patients with neurocysticercosis.

We studied the effect of perilesional gliosis on seizure recurrence after stopping antiepileptic drug (AED) therapy in 108 patients with a solitary cysticercal brain cyst. All patients received albendazole therapy in the beginning, and magnetic resonance imaging (MRI) done after 2 seizure-free years showed complete disappearance of the lesion in 67, partial degeneration in 12, and healing by calcification in 29. The gliosis, which was not visible on initial MRI, was observed near the lesion in 22 (20%) patients on T1-weighted magnetization transfer spin-echo (MTSE) MRI. Initial seizure control was difficult with single AED therapy in 16 of 22 patients with gliosis but only in 8 of 86 patients without gliosis. On stopping AED therapy, patients with perilesional gliosis had a higher incidence of seizure recurrence (19 of 22 patients) compared with those who did not demonstrate gliosis (9 of 86 patients). The presumption that gliosis visible on MTSE MRI correlates with seizure recurrence had a high specificity (96%) but only moderate sensitivity (68%). Our findings suggest that there is a group of patients with neurocysticercosis in whom the risk of seizure recurrence is actually high. Several such patients have perilesional gliosis that can be identified on T1-weighted MTSE MRI. These patients probably need long-term AED administration.

Adult↗
PubMed2000

Clinical implications of hepatitis G virus (HGV) infection in patients of acute viral hepatitis & fulminant hepatic failure.

BACKGROUND & OBJECTIVES: Viral hepatitis is a major public health problem especially in developing countries such as India. Hepatitis viruses A, B, C, D and E are all well characterized and molecularly defined agents with unequivocal association with human liver disease but there is evidence of hepatitis in humans caused by certain transmissible agents which cannot be classified with the above hepatotoric viruses. The role of recently discovered hepatitis G virus (HGV/GBV-C) as an independent heaptitis agent is controversial. Recently, we have shown a relatively high frequency of HGV infection in fulminant hepatic failure but the virus was often detected in co-infection with hepatitis B or E virus. The present study has therefore been carried out to evaluate the clinical significance of HGV infection in acute viral hepatitis (AVH) and fulminant hepatic failure (FHF) through follow up of HGV positive patients till their clinical and biochemical recovery. METHODS: The study included 50 patients comprising 35 of AVH and 15 of FHF. These patients were evaluated on the basis of history, physical examination, liver function profile and serological markers for hepatitis A, B, C and E. Those patients serologically negative for HBV and HCV infection were further screened for HBV DNA and HCV RNA by PCR. All the samples were screened for presence of HGV-RNA by RT-PCR using inner and outer primers sequences selected from NS3 helicase region of the HGV genome. FHF patients who died were subjected to postmortem liver biopsy and these biopsy specimens were also screened for HGV-RNA. Repeat detection of HGV-RNA was done after clinical and biochemical recovery of the patients. RESULTS: Of 35 AVH patients, HGV infection was detected in 5 patients (14.3%) while 4 of 15 patients (26.6%) in the FHF group were positive for HGV-RNA. Five HGV positive AVH patients were followed till clinical and biochemical recovery and all of them tested positive for HGV-RNA at follow up (6 weeks to 6 months). Out of 4 HGV positive FHF patients, only one survived and his repeat sample after clinical and biochemical recovery tested positive for HGV-RNA. INTERPRETATION & CONCLUSIONS: The results suggest that HGV infection does occur in patients of AVH and FHF and HGV viraemia persists for a long time even after clinical and biochemical recovery. These observations point towards a possible non-pathogenic role of hepatitis G virus infection.

Base Sequence↗
PubMed2000

Analysis of serological evidence of different hepatitis viruses in acute viral hepatitis in prisoners in relation to risk factors.

BACKGROUND & OBJECTIVES: The present study describes an outbreak of acute viral hepatitis in an institutional population (inmates of a prison) with an aim to delineate the etiological agents of this outbreak and to analyse the clinical, biochemical and serological evidence of different hepatitis viruses in relation to risk factors. METHODS: Fifty patients of acute viral hepatitis identified during the outbreak were evaluated on the basis of history, clinical examination, risk factor distribution, biochemical profile and serological markers for hepatitis A-E infection. Adequate epidemiological data were collected from prison administration including housing of prisoners, food and water supply. RESULTS: Of the 50 patients, 35 (70%) had serological evidence of HEV infection. Evidence of HBV infection was found in 17 patients (34%), HAV infection in 2 (4%) and HCV in 8 (16%) patients. While 16 patients (32%) had evidence of multiple viral infections, none of the viral markers could be detected in 8 patients (16%). One or more risk factor(s) could be identified in more than half of the subjects (26/50; 52%). There were 11 patients who gave history of more than one risk factor while 24 (48%) patients had none of the risk factors. INTERPRETATION & CONCLUSIONS: HEV was found to be the major cause of the outbreak and contamination of drinking water supply could be the possible source of infection. This outbreak was seroepidemiologically similar to other outbreaks of hepatitis occurring in the country with HEV being the most common cause. However, there was evidence of multiple viral infections, particularly HBV and HCV in the high-risk predisposed prison population.

Adolescent↗
PubMed2000

Primary PNET of kidney: report of two cases and review of literature.

PNET of the kidney is a rare tumor with only a few published reports. In view of poorer prognosis and different therapeutic approach, renal PNET should therefore be differentiated from other primary renal neoplasma such as Wilms tumor, renal neuroblastoma and malignant rhabdoid tumor which on histology resemble renal PNET. Two cases of renal PNET have been described in this report. Cut surface of the tumor in both cases was greyish white lobulated, with multiple tiny cystic areas. Histologically, tumor consisted of loosely cohesive sheets of small to medium sized monomorphic cells with round nuclei and little cytoplasm. Tumor cells showed diffuse strong membrane positivity for MIC2 and focal weak to moderate positivity for NSE and vimentin. Renal PNET should therefore be included in differential diagnosis of rapidly enlarging renal lumps presenting with local infiltration and aggressive behaviour, particularly in children and young adults. Diffuse strong membrane positivity for MIC2 in PNET is helpful in differentiating it from other primary renal neoplasms.

12E7 Antigen↗
PubMed1999

Parkinsonism due to predominant involvement of substantia nigra in Japanese encephalitis.

OBJECTIVE: To study the clinical correlates of lesions seen predominantly in the substantia nigra in some patients with Japanese encephalitis (JE). BACKGROUND: JE typically involves thalamus, brainstem, spinal cord, and cerebral cortex. Rarely, basal ganglia and cerebellum may be affected. Lesions are often widespread and discrete. Predominant involvement of substantia nigra in JE has not been previously reported. METHODS: Of 52 patients with JE seen in an endemic zone, five were selected on the basis of isolated lesions in the substantia nigra on MRI; all were subjected to detailed clinical and laboratory evaluation. RESULTS: Presenting symptoms were fever, alteration of consciousness, neck stiffness, and decreased body movements. Examination during acute illness revealed restricted eye movements, opsoclonus, upbeating nystagmus, and cogwheel rigidity. There was early and complete recovery of consciousness and eye signs. Parkinsonian features such as positive glabellar tap sign, masklike face, bradykinesia, tremors, and postural instability became apparent as these patients started walking. Reversible mutism was observed in three patients during the acute phase. Response to levodopa, amantadine, and trihexiphenedyl was partial. Three patients were followed for more than 1 year, during which time their parkinsonian features recovered completely. Substantial recovery was also observed in the two other patients 2 months after regaining consciousness. CONCLUSIONS: Some patients with Japanese encephalitis may have lesions predominantly in the substantia nigra. After recovery from acute encephalitic illness, they manifest clinically with typical parkinsonian features. Although several viruses are known to cause parkinsonism, this is the first demonstration of a virus producing lesions predominantly in the substantia nigra and causing parkinsonism.

Adolescent↗
PubMed1999

Cytodiagnostic patterns of metaplastic breast carcinoma in aspiration samples: a study of 14 cases.

Metaplastic breast carcinomas (MBCs) are not only uncommon neoplasms but also show a myriad of cytomorphologic patterns in aspiration samples. These tumors comprise less than 5% of breast malignancies and have an uncertain prognosis. In this study, the fine-needle aspiration cytologic features of 14 MBCs with the identification of two distinct malignant cell populations are presented, based on which a definitive diagnosis was possible in 12 of the 14 cases. In the remaining 2 cases the diagnosis of MBC was substantiated after study of cell blocks from the aspirate, which were made in all the cases. Furthermore, the diagnosis of MBC was also confirmed subsequently on tissue examination. The various combinations of patterns included malignant ductal, squamous, and sarcomatous (including heterologous) elements and multinucleated osteoclastic giant cells. As a result of this study, it was felt that if malignant breast aspirates on careful examination show two or more distinct neoplastic elements, the diagnosis of MBC may be possible.

Adult↗
PubMed1999

Fine-needle aspiration cytology of adenoid cystic carcinoma of the breast.

Adenoid cystic carcinoma (ACC) of the breast is a rare variant of breast malignancy and has a better prognosis than its counterpart in the salivary glands. In this communication, our experience with seven cases of ACC of the breast is presented in which the diagnosis was established on fine-needle aspiration cytology (FNAC). The cytologic samples in all cases were cellular and featured three-dimensional clusters of uniform ductal epithelial cells with cystic spaces, bland nuclei, fine chromatin, and scanty cytoplasm arranged around spheres or cores of homogenous material. The cytodiagnosis of ACC in all cases correlated with subsequent examination of cell blocks of the aspirate and tissue. The cytodiagnostic criteria for ACC of the breast which are useful in a correct FNAC diagnosis are discussed.

Adult↗
PubMed1999

Immunoreactivity of prostate-specific antigen in male breast carcinomas: two examples of a diagnostic pitfall in discriminating a primary breast cancer from metastatic prostate carcinoma.

Prostatic-specific antigen (PSA) is regarded as a specific marker secreted by normal and neoplastic acinar epithelial cells of the prostate gland; its detection by immunocytochemistry has been accepted as an indication of metastatic prostate cancer. This is ascribed to the commonly held belief that PSA is not found in extraprostatic tissues. However, this concept has recently been challenged, based on the observations that certain nonprostatic tissues and their neoplasms can also secrete PSA. Such a questionable belief could result in a diagnostic pitfall when using immunostaining for PSA on fine-needle aspiration (FNAC) cytology samples to differentiate metastatic prostate cancer from a primary carcinoma of an extraprostatic organ. In this communication, two cases of primary carcinomas of the male breast are reported in which PSA immunopositivity on FNAC led to the suggestion of a diagnosis of metastatic carcinoma of the prostate. Diagn. Cytopathol. 1999;21:167-169.

Acid Phosphatase↗
PubMed1999

Inverse correlation between choline magnetic resonance spectroscopy signal intensity and the apparent diffusion coefficient in human glioma.

Magnetic resonance spectroscopy and diffusion magnetic resonance imaging (MRI) characteristics of human intracranial glioma were studied. Present knowledge suggests a hypothetical inverse relationship between the characteristic choline signal intensity elevation and the apparent diffusion coefficient (ADC) in glioma. Twenty cases of glioma were examined with diffusion-weighted echoplanar imaging and proton magnetic resonance spectroscopic imaging (1H-MRSI). A statistically significant inverse correlation between the choline signal intensity and the ADC was found (P = 0.0004) in radiologically defined tumor-containing regions. This study is the first in which diffusion MRI and 1H-MRSI were used to evaluate human intracranial glioma jointly. It provides insight into how to interpret choline signal intensity elevation in terms of tumor cellularity and proliferative potential when ADC images are also available.

Adult↗
PubMed1999

Evaluation of a guinea pig model to assess interference in the immunogenicity of different components of a combination vaccine comprising diphtheria, tetanus and acellular pertussis (DTaP) vaccine and haemophilus influenzae type b capsular polysaccharide conjugate vaccine.

A guinea pig model to assess the immunogenicity of a combination vaccine containing diphtheria, tetanus and acellular pertussis (DTaP) vaccine and Haemophilus influenzae type b (Hib) capsular polysaccharide conjugated to tetanus toxoid (HibT) was evaluated comparatively with the mouse immunogenicity test to study the effect of combining these antigens on the immunogenicity of various components. The immunogenicity test in mice was performed by subcutaneous injection of groups of 10 animals twice at an interval of four weeks with 1/10 of a single human dose of various formulations of combination vaccines, DTaP or HibT vaccine. The animals were bled at 4 and 6 weeks and IgG or total antibodies to various components were determined by ELISA or RIA. The guinea pig immunogenicity model included groups of animals injected subcutaneously twice at an interval of six weeks with 1.5 times the single human dose of various formulations. The animals were bled at 4, 6 and 8 weeks and serum samples were tested for antibodies to various components by ELISA, RIA and/or neutralization tests. Additionally, potency of tetanus and diphtheria components was assessed as per the US Food and Drug Administration's regulations. Aluminium phosphate (AIPO(4)) adsorbed HibT vaccine or HibT as a combination with AIPO(4)adsorbed DTaP vaccine showed significant increases in IgG antibodies to tetanus toxin in mice as well increased tetanus antitoxin levels in guinea pigs as compared to soluble HibT vaccine. In general, combining DTaP and HibT vaccines did not affect the antibody levels to tetanus and diphtheria toxoids whereas DTaP-HibT combination vaccine elicited significantly lower IgG antibodies to pertussis toxin and filamentous haemagglutinin than DTaP vaccine alone, particularly after first injection. Mice showed similar Hib antibody responses for the combination and HibT alone whereas guinea pigs consistently showed lower anamnestic responses to Hib for combination formulations than for HibT alone. Reducing the amount of HibT and/or tetanus toxoid in the combination formulations reduced this suppression of Hib antibody response in guinea pigs. Suppression of Hib antibody response in combination vaccines has also been reported from recent clinical trials. Based on the results from this study, it appears that the guinea pig model may be able to predict the human response to various components of combination vaccines.

Animals↗