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Biomedical subjects

S R Mehta

Publications and source records attributed to S R Mehta.

At least 37 records · Page 2Linked to original sources
PubMed1998

The circadian pattern of ischaemic heart disease events in Indian population.

A circadian variation of the onset of almost all ischaemic heart disease (IHD) manifestations with an increased incidence between 6:00 a.m. to 12:00 noon has been reported in several publications during the last decade. This study included 605 patients of various IHD subgroups, i.e., acute Q-wave myocardial infarction (n = 174), unstable angina (n = 266), non-Q myocardial infarction (n = 67), acute pulmonary oedema (n = 35) and sudden cardiac death (n = 63) proven to be due to IHD by electrocardiogram and/or autopsy. In overall, 33.55% (p < 0.0001) of patients had the IHD events with an increased frequency between 6:00 a.m. To 12:00 noon (2nd quarter of the day.) The distribution in the remaining, 1st 3rd and 4th quarters was 22.64%, 20.99% and 22.80%, respectively. Similar circadian rhythm (2nd quarter peak) was seen in males (n = 486), females (n = 119), patients ages < 60 years (n = 388), patients without past history of IHD (n = 434) and in those not on any medications (n = 359). However in patients with past history of IHD and diabetics, the circadian distribution did not differ from the random and the cases were distributed almost evenly in all the four quarters of the day. 39.08% of all the acute Q wave myocardial infarction (A-QMI), 33.45% of unstable angina and 36.5% of sudden cardiac deaths also occurred between 6:00 a.m. and 12:00 noon. However 51.42% cases of acute pulmonary oedema were encountered in the 4th quarter of the day and patients with non Q-myocardial infarction (non-QMI) did not show any particular pattern in relation to circadian rhythm. Thus it was inferred that in Indian population too the circadian pattern of IHD manifestations are similar to other population studies and morning appears to be the time, when the triggers (transient precipitating risk factors) that lead to these events are likely to be prominent. Study of these triggers and/or early morning pathophysiological changes may go a long way in understanding ischaemic heart disease and suggesting possible means of prevention.

Angina Pectoris↗
PubMed1998

The changed clinical spectrum of malaria due to drug resistance.

The clinical spectrum of 14 cases of Plasmodium falciparum malaria (PF) who received empirical treatment and suffered from initial prolonged mild illness culminating into severe complicated malaria are presented. The empirical treatment (ET) consisted of adequate doses of chloroquine in 9, chloroquine with pyrimethamine-sulphadoxine combination in 3 and pyrimethamine-sulphadoxine alone in 2 cases. Moderate fever and weakness persisted for 7 to 28 days leading to anaemia and progressive hepatosplenomegaly in all patients. Other clinical features noticed included jaundice in 5, sudden shock with pulmonary oedema in 4, cerebral malaria and renal failure in 3 each and multiorgan in 4 cases. Subsequent investigations revealed PF rings in 9 cases, mixed PF and vivax infection in 3 and PF gametocytaemia only in 2 patients. Seven patients received quinine, 4 quinine with doxycycline and 3 were given quinine followed by injection artemether. Exchange transfusion was carried out in two cases. Four patients died. The empirical treatment with first line antimalarials alters the clinical profile of resistant PF, makes it milder temporarily, delays in confirming the diagnosis and leads to high mortality. There is urgent need for more diligent early workup for these patients who linger on with moderate pyrexia, progressive hepatosplenomegaly, anaemia and jaundice after ET till better diagnostic methods are available to avoid the prolonged illness and high mortality.

Adolescent↗
PubMed1996

In vivo collagen turnover following experimental balloon angioplasty injury and the role of matrix metalloproteinases.

Extracellular matrix formation is the major component of the restenosis lesion that develops after balloon angioplasty. Although ex vivo studies have shown that the synthesis of collagen is stimulated early after balloon angioplasty, there is a delay in accumulation in the vessel wall. The objectives of this study were to assess collagen turnover and its possible regulation by matrix metalloproteinases (MMPs) in a double-injury iliac artery rabbit model of restenosis. Rabbits were killed at four time points (immediately and at 1, 4, and 12 weeks) after balloon angioplasty. In vivo collagen synthesis and collagen degradation were measured after a 24-hour incubation with [14C]proline. Arterial extracts were also run on gelatin zymograms to determine MMP (gelatinase) activity. Collagen turnover studies were repeated in a group of 1-week postangioplasty rabbits that were treated with daily subcutaneous injections of either a nonspecific MMP inhibitor, GM6001 (100 mg/kg per day), or placebo. Collagen synthesis and degradation showed similar temporal profiles, with significant increases in the balloon-injured iliac arteries compared with control nondilated contralateral iliac arteries immediately after angioplasty and at 1 and 4 weeks. Peak collagen synthesis and degradation occurred at 1 week and were increased (approximately four and three times control values, respectively). Gelatin zymography was consistent with the biochemical data by showing an increase of a 72-kD gelatinase (MMP-2) in the balloon-injured side immediately after the second injury, peaking at 1 week, and still detectable at 4 and 12 weeks (although at lower levels). In balloon-injured arteries, the MMP inhibitor reduced both collagen synthesis and degradation. Overall, at 1 week after balloon angioplasty, GM6001 resulted in a 33% reduction in collagen content in balloon-injured arteries compared with placebo (750 +/- 143 to 500 +/- 78 micrograms hydroxyproline per segment, P < .004), which was associated with a nonsignificant 25% reduction in intimal area. Our data suggest that degradation of newly synthesized collagen is an important mechanism regulating collagen accumulation and that MMPs have an integral role in collagen turnover after balloon angioplasty.

Angioplasty, Balloon↗
PubMed1994

Experience on loading dose--quinine therapy in cerebral malaria.

Twelve cases of cerebral malaria due to plasmodium falciparum, treated with loading dose of quinine (20 mg/kg salt in 500 ml of 5% glucose infused IV in 4 hrs) are compared with eleven age and sex matched cases treated with conventional dose of 10 mg/kg. The parasite clearance rate was significantly faster in loading dose group. There was no difference in recovery time: the interval between the initiation of treatment to full recovery of consciousness in both groups. One patient had pretreatment hypoglycaemia and two cases in the conventional dose group developed hypoglycaemia during therapy. One patient died in conventional dose group due to multi-organ failure. Two litres blood exchange transfusion was also tried for this case. Mild cinchonism occurred in two cases after loading dose while this was observed only in one case in conventional dose group. There was no significant hypotension or ECG changes in any patient. Loading dose of quinine seems to be well tolerated and may clear parasitaemia faster in case of malaria due to Plasmodium falciparum (PF).

Blood Glucose↗
PubMed1994

Prolactin and cortisol levels in seizure disorders.

Levels of prolactin (PRL) and cortisol were estimated to find out the acute effects of generalised tonic clonic seizures (GTCS), partial seizures and pseudoseizures in 60, 18 and 9 patients respectively. Prolactin levels were estimated at 20, 60 and 120 minutes whereas, cortisol was estimated at 20, 60, and 120 minutes postictally. Cortisol and PRL estimation was also done in 10 healthy controls and 11 patients of epilepsy during interictal phase. Serum PRL levels were elevated (> 25 ng/ml) in 68.33% of GTCS and 11.11% of partial seizure cases. The peak levels were achieved in first 30 minutes after the seizures with a gradual return to base line during subsequent one hour. None of the patients with pseudoseizure showed any rise in serum PRL levels. The interictal PRL levels were normal in all the epileptics. Plasma cortisol levels were elevated during 60 to 120 minute postictal period in 45% of GTCS, 55.55% of partial seizures and 66.66% of pseudoseizure patients. Cortisol appears to be non-selectively triggered by all stressful events but postictal PRL estimation can help in differentiating pseudoseizures from GTCS. While an elevated PRL indicates the occurrence of grandmal seizure, a normal postictal PRL level does not always exclude epileptic seizure, specially a partial seizure.

Adolescent↗
PubMed1994

The roles of myoglobin, MB iso-enzyme of creatine phosphokinase and aspartate aminotransferase in serum in the acute phase of myocardial infarction.

The diagnostic value of serum myoglobin as compared to MB iso-enzyme of creatine phosphokinase and aspartate aminotransferase was investigated in 25 patients admitted on suspicion of acute myocardial infarction with a duration of symptoms less than 6 hours. In group 1 (acute myocardial infarction group), the first blood sample, obtained at a mean time of 3.27 hours after onset of infarction, invariably showed increased myoglobin (mean 2.6-fold normal) whereas MB iso-enzyme of creatine phosphokinase and aspartate aminotransferase were often normal. Peak myoglobin values occurred earlier than peak serum MB iso-enzyme of creatine phosphokinase values. The highest peak values of serum myoglobin were found in patients with extensive myocardial infarction. In group 2 (non-acute myocardial infarction or control group) serial determinations of serum myoglobin, serum MB iso-enzyme of creatine phosphokinase and aspartate aminotransferase were within normal limits. Hence the importance lies with the early detection of serum myoglobin in acute myocardial infarction.

Adult↗
PubMed1993

Ranitidine for the prevention of complications following endoscopic sclerotherapy for esophageal varices.

Thirty one patients with significant esophageal variceal bleed were allocated alternately to receive endoscopic sclerotherapy along with ranitidine 300 mg daily or endoscopic sclerotherapy alone till eradication of varices. The mean sclerotherapy sessions, time and volume of sclerosant required for obliteration of varices were similar for the two groups. The esophageal varices were eradicated in all the patients except three in sclerotherapy alone group. There was statistically significant reduction in frequency of post sclerotherapy mucosal ulcers (P < 0.05) after addition of ranitidine to sclerotherapy. Rebleeding was not only significantly reduced (P < 0.05) in the sclerotherapy with ranitidine group but was minor and did not even require blood transfusion. In sclerotherapy alone group rebleeding was controlled by surgery in two patients and one died due to massive bleeding. The results of this study suggest a beneficial role of ranitidine in reducing post sclerotherapy mucosal ulcers and rebleeding. This effect of ranitidine emphasises the role of acid-pepsin in pathogenesis of these ulcers and its associated morbidity.

Adult↗
PubMed1990

Establishment and characterization of human B-cell lymphoma cell lines using B-cell growth factor.

B-cell non-Hodgkin's lymphomas (NHL-B) have been difficult to establish in long-term cell culture using standard techniques. We report the establishment of five representative cell lines from high grade NHL-B using B-cell growth factor (BCGF). The five NHL-B cell lines display the morphologic, immunophenotypic, genotypic, and biologic characteristics of the lymphoma cells present in the original diagnostic specimen. The cell lines showed at least a sevenfold dose-dependent increase in proliferation in vitro over background in the presence of BCGF. Other putative B-cell growth-stimulating cytokines showed no significant proliferative activity or were inhibitory in some cases. NHL-B cell lines secreted growth factor(s) into culture supernatants that mediated at least a fivefold dose-dependent increase in cell proliferation in autochthonous lymphoma cells and a 10-fold or greater stimulation in growth factor-dependent normal B cell lines in vitro. The cell lines show monoclonal rearrangements of IgH genes and nonrandom chromosomal abnormalities characteristic of NHL-B, while the expression of Epstein-Barr virus associated antigen (EBNA-I) is present in two of the five cell lines. The studies show that lineage-specific growth factors may be used to establish neoplastic B cell lines in vitro, which are important experimental systems for cellular and molecular studies in the NHL-B.

Adolescent↗
PubMed1990

Traumatic heart disease.

Five cases of traumatic heart disease (THD) who sustained blunt chest injury in road accidents are reported. In addition to fracture of the ribs (observed in all the cases), there was fracture of the sternum and rupture of the liver and spleen in one case each. Two patients had flail chest. One presented with recurrent ventricular tachycardia lasting for 72 hours followed by changes suggestive of subendocardial infarction. The second case also had changes like subendocardial infarction and it was preceded by junctional tachycardia with aberrant conduction during the first 48 hours. Ventricular premature beats (VPB) were the only abnormality noted in one case and the remaining two had ST-T wave changes suggestive of inferolateral ischaemia without any arrhythmias. The patient with VPB developed pericardial rub without effusion. There was one death and postmortem revealed ruptured liver and spleen in addition to laceration of the right ventricle and haemopericardium. The electrocardiographic changes persisted for two to eight weeks. All four cases were symptom-free at 12 weeks and treadmill exercise test done after 12 to 18 weeks was normal.

Accidents↗
PubMed1990

Normokalaemic periodic paralysis as the presenting manifestation of hyperthyroidism.

We report a 50 year old male admitted with complaints of episodic weakness. During the attack of paralysis there was no hypokalaemia. There were no clinical signs of thyrotoxicosis, but since thyroid function tests revealed hyperthyroidism, he was treated as a case of thyrotoxic periodic paralysis, with no recurrence of symptoms over 6 months.

Humans↗
PubMed1989

Congenital afibrinogenaemia.

A case of congenital afibrinogenaemia in a young female child is described. She had haemorrhagic tendency since birth in the form of markedly prolonged umbilical bleeding and easy bruising afterwards. Two of her brothers had bleeding tendencies, one died shortly after birth due to uncontrollable umbilical bleeding and other died at the age of 12 years from internal haemorrhage. The family study indicates the mode of inheritance to be probably autosomal recessive. The principal laboratory findings are complete non-coagulability of blood, grossly abnormal coagulation tests, zero ESR value, failure to detect fibrinogen by heat coagulation or chemical precipitation tests and biuret reaction and correction of thrombin time after fibrinogen infusion.

Afibrinogenemia↗
PubMed1989

Multigated radionuclide ventriculography during in-hospital phase of acute myocardial infarction.

Global and regional left ventricular performance was assessed by multigated radionuclide technique in thirty patients sustaining acute myocardial infarction on two occasions during in-hospital phase. Thirteen (76.5%) of the seventeen patients with anterior infarction had depressed initial left ventricular ejection fraction compared with seven (53.8%) of the thirteen patients with inferior infarction. From initial to discharge study, change in ejection fraction was statistically insignificant in either group of infarctions. All except three (10%) patients had regional wall motion abnormality on initial evaluation with little subsequent alteration. Our data demonstrates that ejection fraction changes variably during the course of illness, and location of infarction has profound effect upon degree of left ventricular dysfunction. Assessment by non-invasive radionuclide technique may have prognostic implications.

Adult↗
PubMed1989

Falciparum malaria--present day problems. An experience with 425 cases.

Clinical details and present day problems encountered in 425 cases of falciparum malaria (PF) are reported. 10.11% had taken chloroquine prior to reporting to us. Parasitic count done in 23.05% cases lacked correlation with severity of disease. Pattern of fever varied markedly but 5.4% were afebrile throughout and presented only with bodyache and malaise. Apyrexial spell was noted in 5.64%. 28.70% had typical facial looks of anaemia and sallow complexion. Cerebral symptoms were noted in 3.05%. Other symptoms were severe headache 33.4%, pain abdomen 3.29%, gastroenteritis 5.64%, jaundice 2.58% and bronchitis in 7.50%. We encountered subconjunctival haemorrhages with purpura and/or urticaria in four cases, symptoms suggestive of shock lung in 3, pulmonary oedema in 2, severe anaemia (HB less than 4 g%) in seven pregnant ladies, extrapyramidal symptoms in follow up period in 5 and congenital malaria in 2 cases. 83.25% were cured with chloroquine and oxytetracycline. 8.47% (who deteriorated despite the above treatment) were treated with quinine for 6 days. 5.17% (with severe disease) were also given quinine as first line drug. 2.82% (unresponsive to chloroquine and oxytetracycline but with mild disease) were treated with pyrimethamine-sulphamezathine combination for 5 days. One case who did not respond to quinine was treated with quinidine. Recrudescence was seen in 3.67% of patients treated with chloroquine and oxytetracycline. There was no case with renal failure, haemolysis due to G6PD deficiency and black water fever. There was only one death (0.23%) in our series. Self-medication, haphazard therapy and the slogan "Fever may be malaria-take chloroquine" can lead to problems in falciparum malaria.

Adolescent↗