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R K Gupta

Publications and source records attributed to R K Gupta.

At least 217 records · Page 12Linked to original sources
PubMed1997

MRI in Japanese encephalitis.

We document the MRI features in seven patients with Japanese encephalitis. MRI was carried out on a 1.5 T system within 10-60 days of onset. In all the patients MRI revealed bilateral thalamic lesions, haemorrhagic in five. Signal changes were present in the cerebrum in four patients, the midbrain and cerebellum in three each, the pons in two and the basal ganglia in one. The lesions were haemorrhagic in three of the four patients with lesions in the cortex, two of the three with lesions in the midbrain and cerebellum, but the pontine lesions were haemorrhagic in both patients. Spinal cord involvement was seen in one of the three patients who underwent MRI. In two patients MRI was repeated 3 years after the onset, showing marked reduction in abnormal signal; and all the lesions gave low signal on both T1- and T2-weighted images. Bilateral thalamic involvement, especially haemorrhagic, may be considered characteristic of Japanese encephalitis, especially in endemic areas.

Adolescent↗
PubMed1997

MRI of the brain in patients with miliary pulmonary tuberculosis without symptoms or signs of central nervous system involvement.

MRI was performed on patients with miliary pulmonary tuberculosis to look for brain involvement and to study the features sequentially, during treatment. We studied seven patients with typical radiographic tuberculosis, and no symptoms or signs of central nervous system involvement. Conventional spin-echo (SE) imaging, including contrast enhanced images, was performed in all cases. All patients showed brain involvement: four patients showed lesions mainly less than 3 mm in diameter, better seen on contrast-enhanced images. These patients showed oedema around the lesions after 2 months of treatment, with subsequent regression on follow-up. The remaining three patients had multiple lesions, 3 mm or more in diameter, which showed a gradual decrease on follow-up. We conclude that the brain may commonly be involved in miliary pulmonary tuberculosis. The response to treatment depends on the stage of the granuloma and shows a definite pattern of healing on follow-up.

Adolescent↗
PubMed1997

Takayasu's arteritis: evaluation with three-dimensional time-of-flight MR angiography.

Three-dimensional time-of-flight MR angiography was performed in 16 patients with Takayasu's arteritis. Two regions were evaluated, the arch of aorta and its intrathoracic major branches, and the abdominal aorta with proximal portions of its major visceral and renal branches. Individual arteries and aortic segments, i. e. aortic arch and abdominal aorta, were evaluated for abnormalities such as stenosis, occlusion, dilatation and aneurysm formation. The results were compared with contrast angiography. Follow-up MR angiography was performed in three patients after 9-12 months. MR angiography demonstrated steno-occlusive lesions in all the patients and aneurysms in 2. In comparison with contrast angiography, good correlation was found in 129 of the 145 arteries and aortic segments. For the 12 false-positive results, incorrect slab placement and overestimation of stenosis were implicated. Interestingly, there were three false-negative results and one occlusion was underestimated as stenosis. A new lesion developed in 1 patient and one stenosis progressed in another patient upon follow-up. Three-dimensional time-of-flight MR angiography is a simple and fairly accurate method for documenting the lesions in Takayasu's arteritis and for its follow-up.

Adolescent↗
PubMed1997

Chronic local tissue reactions, long-term immunogenicity and immunologic priming of mice and guinea pigs to tetanus toxoid encapsulated in biodegradable polymer microspheres composed of poly lactide-co-glycolide polymers.

Immunogenicity of tetanus toxoid (TT) encapsulated in biodegradable polymer microspheres composed of poly lactide (PLA) or poly lactide-co-glycolide (PLGA) polymers was evaluated in mice and guinea pigs for 1 year. Microsphere formulations made from polymers differing in molecular weight and composition elicited significantly higher IgG antibody levels than soluble TT in mice. The antibody levels elicited by microsphere formulations in mice and guinea pigs were similar to those elicited by a single injection of AlPO4 adsorbed TT. Immunogenicity was not consistently better with a particular polymer composition, molecular weight or microsphere size. However, animals primed with TT-containing microspheres showed significantly higher anamnestic response to a low dose booster 1 year after priming than those primed with AlPO4 adsorbed TT. Microspheres made from low molecular weight PLGA polymer showed a minimal local tissue reaction 1 year after injection. In contrast, aluminum adjuvant formed local granulomas which persisted for 1 year after injection. Microsphere formulations used in this study released a small fraction of antigenic TT during in vitro release studies due to denaturation of TT during encapsulation and hydration of microspheres. Nevertheless, strong priming of immune responses were seen. It remains to be demonstrated whether stabilization of TT would lead to more immunogenic microsphere formulations.

Albumins↗
PubMed1997

Fine needle aspiration cytodiagnosis of sialadenitis with crystalloid formation.

Two cases of sialadenitis with crystalloid formation are here described in which the diagnosis was made by fine needle aspiration cytology. In both cases the enlargement of salivary gland clinically mimicked a neoplasm and the aspiration cytodiagnosis resulted in conservative management and avoided unnecessary surgery.

Biopsy, Needle↗
PubMed1997

Parainfectious myelitis: three distinct clinico-imagiological patterns with prognostic implications.

Seventeen parainfectious myelitis patients were studied for site, extent and severity of lesions. Three patterns were observed each having distinct clinical, electrophysiological and MRI features: 1) focal segmental myelitis--focal cord lesion with long tract signs and good prognosis; 2) ascending myelitis--continuous lesion from conus to mid-cord with upper and lower motor neuron signs (not necessarily spinal shock), dysautonomia and poor outcome; 3) disseminated myelitis--discrete lesions scattered throughout the cord with subtle signs in spinal segmental distribution, above and below the transverse level and moderate outcome. Severe autonomic dysfunction, denervation of paraspinal muscles, "dense" lesion on imaging and often (but not always) the absent somatosensory evoked potentials carried poor outcome. In conclusion "parainfectious myelitis" is a better term to describe transverse myelitis, as the lesion extends to a large vertical extent. Further classification into 3 subgroups may improve understanding of anatomical and physiological dysfunction and prediction of outcome.

Adolescent↗
PubMed1997

Treatable intracranial hypertension in patients with lupus nephritis.

Idiopathic intracranial hypertension is a disorder of intracerebral pressure regulation and patients run the risk of permanent visual loss. Intracranial hypertension (IH) has been reported rarely in systemic lupus erythematosus (SLE). We reviewed the medical records of 127 patients with lupus nephritis (LN) who were followed up from 1987 to 1996 in our unit. There were six patients with IH which gave a disease prevalence of 4.7% in those with LN. All were females giving a disease prevalence of 5.2% for that sex, a high rate of occurrence of IH in patients with LN. Their age ranged from 22 to 34 y (27.8 +/- 3.6 y). Headache, vomiting and diplopia were the common presenting symptoms and had started 7.3 +/- 4.4 weeks prior to the diagnosis of IH. The cerebrospinal (CSF) opening pressure (413.3 +/- 77.0 mmH2O) was raised in all cases. Biochemical and cytological analyses of CSF were normal. The only abnormal radiological finding was partially empty sella in one patient on magnetic resonance imaging (MRI) (performed in three patients) or computed tomography (CT) (performed in all patients). All patients had serological evidences of active lupus disease at the time of diagnosis of IH. The renal histology was WHO type IV in four cases and III and V in one each indicating severe renal involvement. Laboratory evidences of procoagulant activity were found in the form of positive anticardiolipin antibody (aCL) in two patients, lupus anticoagulant (LA) in two and an otherwise unexplained isolated prolongation of activated partial thromboplastin time (APTT) in the other two. Clinically, one or more episodes of symptomatic venous or arterial thrombosis had occurred in all subjects. In addition to symptomatic measures, all subjects were treated with prednisolone, azathioprine, cyclophosphamide and plasmapheresis according to the protocol of our unit. One patient who did not receive plasmapheresis and cyclophosphamide had a relapse while all others recovered completely. None received anticoagulant therapy. Young females with serologically active lupus, severe forms of renal lesions, past history of venous or arterial thrombosis and laboratory evidences of procoagulant activity, appear to be at increased risk of IH. Thrombotic occlusion of the cerebral arteriolar or venous vascular bed eventually affecting the arachnoid villi and impeding CSF absorption is favoured compared to cerebral venous or sinus thrombosis as the pathogenic mechanism. Combined immunosuppression and plasmapheresis appeared to be beneficial in short and long term follow-up. We propose that patients with SLE and IH have definable risk and pathogenetic factors and are no more to be considered 'idiopathic'. The conditions calls for aggressive intervention which leads to an excellent outcome.

Acetazolamide↗
PubMed1997

Altered ionic effects of insulin in hypertension: role of basal ion levels in determining cellular responsiveness.

To investigate the ionic actions of insulin in hypertension, 19F- and 31P-nuclear magnetic resonance spectroscopy were used to measure cytosolic free calcium (Ca(i)) and intracellular free magnesium (Mg(i)) levels in red blood cells from normal (n = 9) and hypertensive (n = 9) subjects before and 30, 60, 120, and 180 min after in vitro incubation with insulin. In hypertensive patients, basal Ca(i) levels were significantly higher (30.0 +/- 2.2 vs. 19.8 +/- 2.5 nmol/L; P < 0.05), and basal Mg(i) levels were significantly lower (170 +/- 10.9 vs. 209 +/- 8 micromol/L; P < 0.05) than in normotensive subjects. In normal cells, insulin significantly elevated Ca(i) to 39.8 +/- 8.0, 50.1 +/- 8.2, 69.3 +/- 11.1, and 50.9 +/- 13.4 nmol/L at 30, 60, 120, and 180 min and Mg(i) to 238 +/- 10,264 +/- 14,226 +/- 11, and 216 +/- 10 micromol/L at 30, 60, 120, and 180 min. In hypertensive subjects, the insulin-dependent Ca(i) elevation was blunted, and Mg(i) accumulation was completely suppressed. Continuous relationships were observed between basal values of each ion and insulin responses; the greater the Ca(i), the less the Ca(i) rose (r = -0.574; P = 0.013), and the lower the Mg(i), the less Mg(i) rose (r = 0.524; P = 0.025). Furthermore, a blunting of Mg(i) responses to insulin could be reproduced in normal cells that were magnesium depleted by prior treatment either with A23187 in a calcium-free medium or with high glucose concentrations (15 mmol/L). Once again, insulin responsiveness followed basal Mg(i) levels (r = 0.637; P < 0.001). Together, these data demonstrate ionic aspects of insulin resistance in hypertension and suggest that Ca(i) and Mg(i) levels may regulate cellular responsiveness to insulin. This may help to explain the different vascular actions attributed to insulin in normal compared with insulin-resistant states such as hypertension.

Adult↗
PubMed1997

Antinociceptive activity of chromophoric chain substituted hemicyaninocolourants.

Some of the chromophoric chain substituted hemicyaninocolourants (CCHCs) were synthesized and confirmed on the basis of nitrogen analysis. These were tested for their antinociceptive activity in albino rats against tail flick technique and sodium chloride induced writhing test. Test compounds were given in graded doses (10, 20 and 50 mg/kg, intraperitoneally) and compared with morphine and aspirin as standard controls. Two compounds CCHC-1 and CCHC-2 showed antinociceptive activity in a dose-dependent manner in both the experimental models. The compound CCHC-3 did not exhibit antinociceptive activity to any significant extent.

Analgesics↗
PubMed1997

Problems in differentiating intradural lipoma from dermoid on magnetic resonance imaging.

Spinal intradural subpial lipomas are rare lesions. This case report emphasizes the role of MRI in diagnosing this lesion and in delineating its location. However, a dermoid cyst with a high lipid content of mixed triglycerides and unsaturated fatty acids without cholesterol may present the same appearance as an intradural lipoma and cannot be differentiated from it even with the use of short T1 inversion-recovery (STIR) images.

Adult↗
PubMed1997

Hemiplegia.

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Age of Onset↗
PubMed1997

MR imaging, MR angiography, and MR spectroscopy of the brain in eclampsia.

PURPOSE: To compare the MR imaging and MR angiographic changes with in vivo proton MR spectroscopic findings and to determine the spectral differences between edema and ischemia in patients with eclampsia. METHODS: Spin-echo MR imaging, MR angiography, and single-voxel proton MR spectroscopy were performed in 10 patients with eclampsia. MR studies were obtained within 3 to 5 days of diagnosis and repeated after 2 weeks with identical parameters. RESULTS: Multifocal subcortical/cortical hyperintensities were noted in all 10 patients on T2-weighted images; in two patients, hyperintensities were seen in both cerebral hemispheres. In nine patients, MR angiograms showed narrowing of the major vessels constituting the circle of Willis that resolved after 2 weeks. In one patient with subtle imaging changes, MR angiography showed mild bilateral narrowing of the proximal middle and posterior cerebral arteries that did not change after 2 weeks, whereas imaging abnormalities worsened. Findings at single-voxel MR spectroscopy of the reversible T2 hyperintense lesions were significantly different from findings in the control group for N-acetylaspartate (NAA)/creatine ratios. One patient with mild abnormalities at MR imaging and MR angiography had lactate and decreased creatine and NAA, and on a follow-up study had a further decrease of NAA and creatine as well as a decrease in lactate. CONCLUSION: In vivo proton MR spectroscopy may help to differentiate cerebral edema from ischemia in patients with eclampsia and thus may help to determine the prognosis for these patients.

Adolescent↗