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Biomedical subjects

R K Gupta

Publications and source records attributed to R K Gupta.

At least 181 records · Page 10Linked to original sources
PubMed1998

Fine-needle aspiration cytology of a minimal carcinoma of the breast with neuroendocrine features.

A case of breast carcinoma with neuroendocrine features is described in a 62-year-old nulliparous female, in which the fine-needle aspiration cytodiagnosis was of a breast carcinoma. Carcinoma of the breast with neuroendocrine features is an unusual variant which may be observed in several histologic types of mammary carcinoma. An awareness of this tumor is essential in view of the increasing use of fine-needle aspiration cytology as a minimally invasive, first line of investigation of a breast abnormality. The case presented here is also of interest since the tumor was only 5 mm in diameter (a minimal carcinoma).

Biopsy, Needle↗
PubMed1998

Fine-needle aspiration cytology of metastatic clear-cell renal carcinoma presenting as a solitary mass in the head of the pancreas.

In nearly 25% of patients with primary renal-cell carcinoma, metastasis is not uncommon and usually does not give rise to difficulties in diagnosis. However, its presentation as a mass in the head of the pancreas following an elapse of several years after the initial diagnosis of renal carcinoma is not only uncommon but may be confused clinicoradiologically with a primary pancreatic adenocarcinoma. The case presented here illustrates such an example with an emphasis on the usefulness of fine-needle aspiration cytology (FNAC) in the diagnosis.

Adenocarcinoma, Clear Cell↗
PubMed1998

Fine-needle aspiration cytology of soft-tissue calcinosis presenting as an enlarging mass in the chest wall.

Calcinosis cutis is an uncommon condition, and calcific deposits in patients with end-stage renal disease are now somewhat rare, due to improvement in management. Since calcific deposits may clinically resemble a tumor, it is feasible to investigate them by fine-needle aspiration cytology (FNAC). A 52-yr-old male with a history of end-stage renal failure presented with a 2-cm mass in the left chest wall. Within 6 mo the mass enlarged to nearly four times its original size. In view of clinical suspicion of malignancy, FNAC was performed. Cytopreparations showed abundant calcium, indicative of soft-tissue calcinosis. The case is interesting, since the known history of end-stage renal failure enabled the FNAC diagnosis of soft-tissue calcinosis.

Biopsy, Needle↗
PubMed1998

A simple and rapid method for measuring unconjugated capsular polysaccharide (PRP) of Haemophilus influenzae type b in PRP-tetanus toxoid conjugate vaccine.

The authors developed a simple and rapid method for quantitation of free capsular polysaccharide of Haemophilus influenzae type b (polyribosyl ribitol phosphate, PRP) in PRP-tetanus toxoid conjugate vaccine based on acid precipitation of tetanus toxoid (TT). Acid hydrolysis of PRP during the assay was not detected. The conditions used in the assay did not precipitate unconjugated PRP or adipic acid dihydrazide derivatized PRP. The method was highly reliable, reproducible and sensitive. The accuracy of the assay was confirmed by spiking known amounts of unconjugated PRP to PRP-TT conjugate preparations. A PRP-TT preparation, incubated at 37 degrees C for 6 months showing most of the PRP as unconjugated (87% determined by this method), was not immunogenic in mice for the PRP component even after two injections. In contrast, the same preparation held at 4 degrees C for 20 months, showing 17% unconjugated PRP, induced IgG antibodies to PRP which were boosted after second injection. Therefore, this method is very useful to evaluate the stability of PRP-TT conjugate vaccine. The assay may be useful for characterizing other polysaccharide-protein conjugate vaccines.

Animals↗
PubMed1998

MR demonstration of a giant cavernous carotid aneurysm with occlusion of the contralateral intracranial carotid artery: an unusual complication of cavernous sinus thrombosis.

We present an unusual combination of vascular complications of cavernous sinus thrombosis in a 7-year-old girl. MRI and MR angiography showed occlusion of the intracranial portion of the left internal carotid artery and a contralateral giant cavernous carotid aneurysm. This combination of vascular findings may influence the management in such cases.

Aneurysm, Infected↗
PubMed1998

Alterations in heart and kidney membrane phospholipids in hypertension as observed by 31P nuclear magnetic resonance.

Abnormalities of phospholipids in hypertension have previously been described in human erythrocyte, platelet, and plasma lipoproteins. Since the heart and kidney are adversely affected by hypertension, we investigated possible alterations in their membrane phospholipids, which could play a role in the derangement of intracellular ion balance widely observed in hypertension. The phospholipid compositions of heart and kidney from spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats were determined by using 31P nuclear magnetic resonance (NMR) spectroscopy. Absolute contents of all phospholipids in hypertensive hearts and kidneys were significantly higher than in normotensive hearts and kidneys. Expressed as a fraction of total phospholipid, cardiolipin (CL) and phosphatidylethanolamine plasmalogen (PEp) were significantly increased in SHR hearts compared to WKY hearts (CL and PEp were 7.95+/-0.22% and 13.16+/-0.35% in SHR vs. 7.01+/-0.20% and 11.19+/-0.42% in WKY rats, P< or =0.05), but phosphatidylethanolamine (PE) and phosphatidylcholine (PC) were significantly decreased in SHR (PE and PC were 22.46+/-0.37% and 44.81+/-0.43% in SHR vs. 24.02+/-0.44% and 46.01+/-0.50% in WKY rats, P< or =0.05). In the phospholipids extracted from rat kidneys, the percentage of PE was significantly higher for SHR than for WKY rats (20.37+/-0.60% vs. 18.43+/-0.37%, P< or =0.05), while PEp and phosphatidylserine (PS) were significantly lower for SHR (PEp and PS were 10.22+/-0.36% and 8.42+/-0.28% in SHRs vs. 11.29+/-0.36% and 9.71+/-0.40% in WKY rats, P< or =0.05). The above alterations in phospholipid composition might contribute to the higher oxygen consumption in the hypertensive heart and abnormal intracellular ion concentrations and ion transport in the heart and the kidney in hypertension.

Animals↗
PubMed1998

Continuous osmotic minipump infusion of alcohol into brain decreases brain [Mg2+] and brain bioenergetics and enhances susceptibility to hemorrhagic stroke: an in vivo 31P-NMR study.

31P-NMR spectroscopic studies were performed in vivo on brains of rats chronically infused for 7 and 14 days with 30% ethanol (in the third cerebral ventricle). Peripheral blood alcohol concentration (BAC) rose to between 16.5-30.5 mg/dl. Brain intracellular free Mg2+ ([Mg2+]i) fell 33-39%, brain mitochondrial cytosolic phosphorylation potential (CPP) fell 31-48%, and brain phosphocreatine (PCr) fell approximately 15%; however, neither brain intracellular free hydrogen ion concentration (pHi) nor brain intracellular inorganic phosphate (Pi) were affected significantly by the chronic release of ethanol from the brain implants. Correlations were found between [Mg2+]i and [PCr] and between [Mg2+]i and CPP. Although brain free [MgADP] was not affected, [MgATP] fell by almost 20% accompanied by a 35-40% rise in free [ADP]. Interestingly, 14-day surgical implantation of 0.9% sterile saline into the third cerebral ventricle was associated with a 20% fall in brain [Mg2+]i and a 35% fall in CPP; however, PCr, ATP, or pHi was not significantly altered. Systemic administration of 4 g/kg ethanol into the 7- and 14-day chronic ethanol animals resulted in a 9- and 12-fold increase in hemorrhagic stroke mortality compared to naive, control rats. Eating habits, grooming, gait and arterial blood pressure were not affected by the chronic brain implantation of ethanol. These data lend support to the notion, primarily based on epidemiologic evidence, that chronic exposure to alcohol can pose a high risk for hemorrhagic stroke. Our alcohol pump-implanted rats also might provide a new model of slow, moderate alcohol intoxication.

Adenosine Triphosphate↗
PubMed1998

Magnesium deficiency exacerbates brain injury and stroke mortality induced by alcohol: a 31P-NMR in vivo study.

Mimicking in rats the reduced level of dietary magnesium (Mg) intake, seen in present-day Western World populations, short-term (4 weeks) restriction of Mg intake (30-35% normal) resulted in a 40% loss in brain intracellular free Mg2+ ions ([Mg2+]i) and significant rises in brain intracellular pH (pHi) and phosphocreatine ([PCr]) but no change in [ATP] or [Pi] as measured by 31P-NMR spectroscopy. Such Mg-deficient animals (serum Mg fell 65%), when given ED40 stroke doses of ethanol, demonstrated a 100% stroke mortality. These findings indicate that: 1) moderate, short-term Mg deficiency makes the brain vulnerable to hypoxic-lethal stroke insults induced by alcohol administration, and 2) brain [Mg2+]i appears to play an important role in finely regulating brain pHi and [PCr].

Animals↗
PubMed1998

Alterations in membrane fatty acid unsaturation and chain length in hypertension as observed by 1H NMR spectroscopy.

Alterations in fatty acids of membrane phospholipids in essential hypertension may account for altered membrane ion transport, elasticity, and contractility properties of hypertensive tissues. To investigate the abnormalities in membrane fatty acids in essential hypertension, the degree of fatty acid unsaturation ([-CH=CH-]/[-CH3]), the average carbon chain length, ratio of glycerol to fatty acyl chains, ratio of phosphatidylcholine to fatty acyl chains, and the ratio of free and acylated cholesterol to fatty acyl chains in fatty acid fractions of membrane phospholipids of aorta, kidney, and heart were determined in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats by 1H nuclear magnetic resonance (NMR) spectroscopy. The degrees of fatty acid unsaturation in the aorta and the kidney membranes were significantly lower in SHR than in WKY rats (aorta, 0.53+/-0.01 v 0.63+/-0.01, n = 5, P = .01; kidney, 0.70+/-0.01 v 0.84+/-0.03, n = 10, P = .01). No significant difference could be detected in fatty acid unsaturation in heart membranes between these two strains. For aorta, kidney, and heart membranes, the average carbon chain lengths of fatty acid fractions of membrane phospholipids were significantly shorter for SHR than for WKY rats (aorta, 15.1+/-0.2 v 18.3+/-0.7, n = 5, P = .02; kidney, 14.5+/-0.2 v 16.4+/-0.4, n = 10, P = .01; heart, 17.3+/-0.5 v 18.8+/-0.6, n = 10, P = .05). The lower unsaturated fatty acid content in membrane phospholipids of the aorta and the kidney, with concomitant reduction in average chain length, may arise from increased oxidation of fatty acid double bonds in hypertensive tissues and may account, in part, for the increased aortic stiffness and abnormal kidney function associated with essential hypertension. Whether the lower unsaturated fatty acid content and decreased carbon chain length of phospholipid membranes in the aorta and the kidney are a cause or a consequence of the high blood pressure, however, remains unknown.

Animals↗
PubMed1998

Positron emission tomography plus serum TA90 immune complex assay for detection of occult metastatic melanoma.

BACKGROUND: Whole-body positron emission tomography (PET) using 18F-fluorodeoxyglucose is very sensitive for detection of metastatic melanoma. We previously reported the accuracy of a serum TA90 enzyme-linked immunosorbent assay (ELISA) in predicting the recurrence of early-stage melanoma. This serum ELISA measures a circulating immune complex composed of TA90 a tumor-associated 90-kD glycoprotein antigen, and its IgG antibody. We hypothesized that using PET examination in conjunction with our serum TA90 ELISA would increase the detection of occult melanoma lesions. STUDY DESIGN: From November 1, 1993 to December 31, 1995, 87 patients underwent PET examination followed within 6 weeks by serum TA90 ELISA. All patients had undergone complete resection of local, regional, or distant metastatic melanoma and had no clinical evidence of disease at the time of PET examination. Each patient had complete followup for 12 months after PET examination. The clinical course was determined by chart review of clinical and radiographic findings. RESULTS: Of the 25 patients who experienced recurrence of disease within 6 months of followup, 22 (88%) had a positive result on one or both tests. Of the 52 patients with a negative result on both tests, 49 (94%) remained disease-free at 6 months of followup. Of the 14 patients who developed distant metastases within 6 months after PET examination, 13 (93%) had a positive PET examination and/or a positive TA90 ELISA. CONCLUSIONS: The TA90 ELISA correlated well with PET examination for detection of metastatic melanoma. The high sensitivity of PET examination plus TA90 ELISA suggests that this combination may have a role in the surveillance of patients at high risk of developing metastatic melanoma.

Adolescent↗
PubMed1998

Demonstration of hepatic steatosis by computerized tomography in patients receiving 5-fluorouracil-based therapy for advanced colorectal cancer.

The frequency and severity of fatty infiltration of the liver in patients receiving 5-fluorouracil (5-FU) and folinic acid has not been documented systematically. Its development can result in difficulty assessing disease progression, and treatment may be altered inappropriately. Twenty-seven patients with colon cancer and liver metastases receiving 5-FU and folinic acid were studied with computerized tomography (CT) before treatment and after six or 12 cycles of chemotherapy. Forty-seven per cent of patients developed hepatic steatosis during treatment. There was no correlation between development of hepatic steatosis and the dose of chemotherapy or the liver function tests. Hepatic steatosis occurs commonly in patients receiving 5-FU and folinic acid and can be severe. Its development can make hepatic metastases difficult to assess and if its benign nature is not appreciated treatment may be inappropriately altered.

Adult↗
PubMed1998

Tuberculous Addison's disease: lack of normalization of adrenocortical function after anti-tuberculous chemotherapy.

OBJECTIVE: Tuberculosis of the adrenal glands is a common cause of Addison's disease in developing countries. We conducted a study to determine if treatment of such patients with modern anti-tuberculous chemotherapy would lead to an improvement in plasma cortisol and aldosterone levels. DESIGN: Prospective study. PATIENTS: 5 patients with Addison's disease secondary to tuberculosis. MEASUREMENTS: Basal and ACTH stimulated plasma cortisol and aldosterone levels were measured prior to instituting anti-tuberculous chemotherapy, as well as one month after its conclusion. Four patients were again studied over the next 2-5 years. RESULTS: Peak plasma cortisol levels prior to treatment were markedly reduced (range, < 14-110 mumol/l). There was no improvement one month (< 14-143 mumol/l) or 2-5 years (< 14-69 mumol/l) after completing anti-tuberculous chemotherapy. Peak plasma aldosterone at diagnosis was < 56-210 pmol/l; it was undetectable in 4 patients. No improvement was observed one month (< 56-210 pmol/l), or 2-5 years (< 56-389 pmol/l) after stopping anti-tuberculous chemotherapy. Plasma aldosterone levels at both these time points were far lower than those in control subjects (median 736 pmol/l, 560-1512 pmol/l; p < 0.01). One patient had an increase in peak aldosterone from < 56 pmol/l to 389 pmol/l, though peak cortisol actually declined in this subject (from 110 mumol/l to 69 mumol/l). CONCLUSIONS: Treatment of tuberculous Addison's disease with anti-tuberculous chemotherapy does not lead to normalization of ACTH stimulated plasma cortisol or aldosterone levels during the 2-5 year period of study. However, prolonged follow up with regular adrenal function tests is warranted in all such patients.

Addison Disease↗
PubMed1998

Induction of immunologic refractoriness in adults by meningococcal C polysaccharide vaccination.

Thirty-four adults were vaccinated with 1/50 of the usual dose of meningococcal polysaccharide vaccine (1 microg of A, C, Y, and W135 polysaccharides, given intramuscularly). This dose was selected as a probe to assess B cell memory. The probe elicited meningococcal C bactericidal antibody responses in all 18 adults who had been vaccinated 4 years earlier with an investigational meningococcal A and C oligosaccharide-protein conjugate vaccine and in the majority of the 11 subjects vaccinated for the first time. In contrast, the responses of the 5 adults given a full dose of licensed polysaccharide vaccine 4 years earlier were <1/10 of those of the other 2 groups. Thus, adults previously given a full dose of meningococcal polysaccharide vaccine show evidence of immunologic refractoriness to group C polysaccharide, whereas refractoriness is not observed after conjugate vaccination. These findings have implications for the use of meningococcal polysaccharide vaccine when the risk of disease is low.

Adult↗
PubMed1998

Role of in vivo proton magnetic resonance spectroscopy in the diagnosis and management of brain abscesses.

OBJECTIVE: In vivo proton magnetic resonance spectroscopy was performed for 24 patients with pyogenic brain abscesses, to examine the consistency of the spectral patterns and to observe the changes in metabolites with treatment. METHODS: Localized proton spectra were obtained from 4- to 8-ml volumes in the abscesses, using stimulated echo acquisition mode and spin echo sequences. Twenty-two patients were treated with combined surgical and medical therapy, and two patients were treated conservatively. High-resolution magnetic resonance spectroscopy was performed for 15 samples of abscesses obtained from these patients, to confirm the assignments of resonances seen in vivo. Postaspiration studies were performed for 12 patients treated with combined medical and surgical therapy and 2 patients treated medically. RESULTS: Lactate and amino acids were seen in spectra for all patients, irrespective of the time of spectroscopy after the onset of combined medical and surgical therapy. Acetate and pyruvate disappeared after 1 week of combined treatment. CONCLUSION: It was concluded that spectral patterns for brain abscesses are consistent and specific and can assist in the noninvasive diagnosis of abscesses. Responses to combined treatment could be monitored by showing the changes in metabolite patterns in serial spectroscopic studies.

Adolescent↗
PubMed1998

Magnetic resonance image detection of coincidental sphenoid sinus aspergillosis and pituitary microadenoma: a potential surgical disaster.

While localizing the microadenoma in a patient with Cushing's disease on magnetic resonance imaging (MRI), fungal granuloma of the sphenoid sinus was coincidentally detected. This helped in the proper management of sphenoidal disease before undergoing trans-sphenoidal removal of the microadenoma, thus averting the possible catastrophe of direct intracranial spread of aspergillus infection.

Adenoma↗
PubMed1998

Phase 1 evaluation of Vibrio cholerae O1, serotype Inaba, polysaccharide-cholera toxin conjugates in adult volunteers.

Conjugate vaccines were prepared by binding hydrazine-treated lipopolysaccharide (DeALPS) from Vibrio cholerae O1, serotype Inaba, to cholera toxin (CT) variants CT-1 and CT-2. Volunteers (n = 75) were injected with either 25 microg of DeALPS, alone or as a conjugate, or the licensed cellular vaccine containing 4 x 10(9) organisms each of serotypes Inaba and Ogawa per ml. No serious adverse reactions were observed. DeALPS alone did not elicit serum LPS or vibriocidal antibodies in mice and only low levels of immunoglobulin M (IgM) anti-LPS in the volunteers. Recipients of the cellular vaccine had the highest IgM anti-LPS levels, but the difference was not statistically significant from that elicited by the conjugates. The conjugates elicited the highest levels of IgG anti-LPS (DeALPS-CT-2 > DeALPS-CT-1 > cellular vaccine). Both conjugates and the cellular vaccine elicited vibriocidal antibodies: after 8 months, recipients of cellular vaccine had the highest geometric mean titer (1,249), followed by DeALPS-CT-2 (588) and DeALPS-CT-1 (330). The correlation coefficient between IgG anti-LPS and 2-mercaptoethanol (2-ME)-resistant vibriocidal antibodies was 0. 81 (P = 0.0004). Convalescent sera from cholera patients had a mean vibriocidal titer of 2,525 that was removed by treatment with 2-ME. The vibriocidal activities of sera from all vaccine groups and from the patients were absorbed (>75%) by LPS but not by either CT-1 or CT-2. Conjugate-induced IgG vibriocidal antibodies persisted longer than those elicited by the whole-cell vaccine. Both conjugates, but not the cellular vaccine, elicited IgG anti-CT.

Adolescent↗