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Biomedical subjects

S Arora

Publications and source records attributed to S Arora.

At least 163 records · Page 9Linked to original sources
PubMed1986

Cellular immune response following thermal injury in human patients.

Cellular immune response was studied longitudinally for a period of 1 month in a group of 51 patients sustaining burns between 20 and 55 per cent of their body surface area. The results indicated lymphocytopenia and significant depression in the total T cells in all the patients. T cells showed a significant rise in their levels in those patients who showed clinical improvement. Further, the loss of expression of 'E' receptor correlated with the lowering of the protein-synthesizing capacity of the mononuclear cells. The functional integrity of the lymphocytes also showed an inability to recognize and stimulate normal alloantigens in an MLR reaction. Investigation of the mechanisms responsible for immunosuppression revealed the generation of T suppressor activity.

Adolescent↗
PubMed1986

Cellular immune mechanisms in thermally injured mice.

An attempt was made to establish an animal model for analysing the cellular immune alterations following thermal injury and to correlate the results with those obtained in humans. A standard burn involving 20 per cent of the body surface area was established in C57 black mice (b1). The results revealed a loss of total T cells until post-burn day 10 and an increase in B cells only during post-burn day 1. The lymphocyte proliferative response to PHA was elevated with the appearance of null cells on post-burn day 10. This observation revealed a generalized depression in the immune responses which was significant until post-burn day 10. However, the results were not comparable with the human studies.

Animals↗
PubMed1985

Partial purification and some properties of a latent CO2 reductase from green potato tuber chloroplasts.

We have partially purified the CO2 reductase, present in green potato tuber chloroplasts, as a latent form. Illumination of the chloroplasts in the absence of substrate, bicarbonate, activated the enzyme, which could then be obtained in soluble forms. Purification of the enzyme was achieved by (NH4)2SO4 fractionation (0-30%) and adsorption and elution from a DEAE-Sephadex A-50 column. The final preparation showed 15-fold purification and 50% recovery of the activity. The pH optimum for CO2 reductase was 8.0. Hepes and Tricine buffers showed maximum activity whereas Tris/phosphate or borate failed to show any activity. The enzyme reaction was sensitive to the presence of metal ions like Fe3+, Hg2+, Cu2+, Mo6+ and Zn2+, however, a threefold activation was observed with Fe2+. The metal requirement for CO2 reductase was evident from the observed inhibition by metal chelators like o-phenanthroline, alpha, alpha'-dipyridyl, bathocuproine, 8-hydroxyquinoline etc. Out of these o-phenanthroline was the strongest inhibitor and its concentration for 50% inhibition was 40 microM. The presence of Fe2+ ions in the reaction mixture protected the enzyme from heat denaturation upto 50 degrees C. Maximum enzyme activity was observed at 15 degrees C. The enzyme activity showed a 30-s lag period and the maximum was reached in 90 s. Supplementation of sodium dithionite in the reaction activated enzyme activity threefold, suggesting involvement of dithiol groups in the catalytic activity. There was strong inhibition by -SH inhibitors like 5,5'-dithiobis(2-nitrobenzoic acid) and N-ethylmaleimide and -SH reagents like dithiothreitol, 2-mercaptoethanol and cysteine. Various nucleotide coenzyme tried inhibited the enzyme strongly.

Aldehyde Oxidoreductases↗
PubMed1985

Burn sera mediated effects on the E-rosetting property of normal active T1 cells.

This study investigates the suppressive effects of burn sera on normal active T1 cells. The results revealed that burn sera collected from survivors and non-survivors during the initial 'shock' phase caused varied effects on the 'E' rosetting properties of normal active T1 cells. However, unlike non-survivor sera convalescent or recovery sera failed to block the 'E' rosetting property of T1 cells. Furthermore, cold incubation in fetal calf sera (FCS) failed to abrogate the loss of T1 cells which were exposed to non-survivor (early) sera; these samples also revealed the presence of antigenic factors. Our experiments were extended to investigate the mechanisms resulting in the irreversible change, and showed that the inhibiting factors could be acting at the microtubular level of the cell cortex.

Animals↗
PubMed1984

Fc and complement receptor integrity of polymorphonuclear (PMN) cells following thermal injury.

In patients sustaining thermal injury, a sequential study was formulated to evaluate Fc and complement receptor expression of polymorphonuclear cells (PMN). Additionally, the role of factors in burn sera and maturity of PMN cells in the circulation were studied. The salient features of the study were: Marked reduction in Fc receptor expression by the 5th day of injury in both survivors and non-survivors. Thereafter levels gradually increased in survivors, though they were still below the normal range. In non-survivors, the depression was severe and persistent. In contrast to Fc receptor expression, complement receptor integrity was not grossly affected in both survivors and non-survivors. Burn sera collected from survivors on the 5th and 13th post-burn day showed reduction in Fc receptor expression of normal PMN cells, whereas sera obtained a month after the injury exhibited no inhibitory effect. Non-survivors sera inhibited Fc receptor expression of normal PMN cells on 5th, 13th and 21st post-burn days. The appearance, increase and disappearance of immature PMN cells in the circulation was correlated with the clinical progress of the patient. Mechanisms involved in the aberrations and its implications are discussed.

Adolescent↗
PubMed1984

"Malignant" contracture of the eye socket.

A new method for reconstruction of "malignant" contracture of the eye socket is described using a simple procedure based on the principle of epithelial inlay. The lining consists of a free skin graft. No cumbersome external appliances for the prevention of contraction of the graft are used; hence the hospitalization is minimized. The results have been satisfactory.

Eye, Artificial↗
PubMed1983

Intracranial venous aneurysms: vein of Galen and other similar vascular anomalies.

Aneurysmal dilatation of the vein of Galen is peculiar to arteriovenous malformation around the midbrain. Similar venous aneurysms may rarely occur in other regions. This paper deals with the radiographic findings in three cases of vascular malformation associated with giant venous aneurysms. The pathophysiology resulting in aneurysmal venous dilatation is discussed based on our material and those previously reported.

Brain↗
PubMed1983

Microglioma--unusual computed tomographic appearance and course of neoplasm.

Microglioma accounts for 0.8-1.5% of primary brain tumors. Eight cases of primary lymphoma of brain are presented. 50% of the patients demonstrated unusual computed tomographic appearances. These patients were divided into three groups depending on clinical outcome. Survival seems to be related to treatment modality. Longest survival times were in patients treated with radiation alone or radiation following biopsy.

Adult↗
PubMed1983

Dermatosis papulosa nigra.

The incidence and natural history of dermatosis papulosa nigra was assessed in eighty-two black patients. The overall incidence in the study population was 77 percent, with a predominance in women of almost 2:1. Fifty-four percent of these patients reported that other members of their families were also affected. The peak incidence and number of lesions occurred in those patients in their sixties. Fair-complexioned blacks had the lowest frequency of involvement. These findings confirm those of other investigators; however, we report a higher than average incidence of involvement in the population we studied.

Adolescent↗
PubMed1982

Epidermoid tumor of the fourth ventricle: use of metrizamide-computed tomography.

This report describes two cases of epidermoid tumor of the fourth ventricle diagnosed with metrizamide computed tomography. They both presented as a low-density lesion in the region of the fourth ventricle on computed tomography. They did not show any enhancement after intravenous injection of contrast medium and had no hydrocephalus. Metrizamide-enhanced computed tomography demonstrated the irregular fourth-ventricular filling defect characteristic of epidermoid tumors.

Adult↗
PubMed1982

Accidental overdose intoxication: a hazard of drug smuggling.

Three patients involved in illicit drug smuggling via the swallowing of high dose, high purity drugs packed in multiple condoms are reported. Two of these patients experienced drug overdose symptoms due to leakage or rupture of the condoms in the GI tract. They were treated successfully.

Adult↗
PubMed1981

Comparative effect of clofibrate, garlic and onion on alimentary hyperlipemia.

The effect of clofibrate on the same subjects in similar test conditions were used as a control to verify the alleged beneficial effects from garlic and onion on alimentary hyperlipemia in normals and in cases with ischemic heart disease. The results showed that clofibrate checked the fat-induced (a) rises of serum triglyceride and plasma fibrinogen, and (b) falls of coagulation time (CT) and blood fibrinolytic activity (BFA). Only garlic had a clofibrate-like effect on CT but both garlic and onion checked the postprandial fall of BFA. Clofibrate, however, increased BFA even above the fasting level. Serum cholesterol and beta-lipoprotein were not appreciably affected by fat with or without any drug. Thus, surprisingly, the so-called beneficial effects of garlic and onion were not seen in subjects who had shown significant changes after clofibrate.

Adult↗
PubMed1981

The long-term use of garlic in ischemic heart disease--an appraisal.

The hypocholesterolemic and fibrinolysis-enhancing properties of garlic were assessed in patients with ischemic heart disease (IHD) and in healthy control subjects. The peak of blood fibrinolytic activity (BFA) achieved at the 4th week of garlic therapy was not sustained despite its continuous use and returned to about the pre-garlic values at the 12th week. Garlic withdrawal did not cause any further change in BFA. Under the same conditions serum total cholesterol (STC) values did not show any significant change. Both of the foregoing features were observed in the IHD as well as in the control group. Garlic therapy for 12 weeks did not cause any appreciable changes in serum triglyceride, beta-lipoprotein, plasma fibrinogen levels or coagulation time in either IHD or control subjects. The evidence cited above does not appear to substantiate the prevalent popular belief in the efficacy of garlic in the management of IHD either as a hypocholesterolemic or as a fibrinolytic agent.

Adult↗
PubMed1979

Delayed-onset pulmonary insufficiency in primates resuscitated from hemorrhagic shock.

Forty-one unanesthetized cynomolgus monkeys were subjected to 2 hours of hemorrhagic hypotension at various mean arterial pressures (MAP) between 40 and 60 mm Hg. Resuscitation and maintenance of MAP were provided by lactated Ringer's solution and homologous blood. Thirty-eight per cent (57% of those surviving greater than 24 hours) developed a delayed-onset (18 to 24 hours) pulmonary insufficiency in spite of good urinary output, and which did not respond to furosemide. The group in which this caused death (24%) showed significantly decreased PaO2, PaCO2, dynamic compliance, and FECO2, and increased minute volume, Qs/Qt, pulmonary artery pressure, and VD/VT before death. Their lungs were heavier, with abnormal pressure/volume curves and increased minimum surface tension. During the entire post-resuscitation phase, this group remained in a high-output, low-resistance hemodynamic state in contract to survivors and those dying of shock. The implications regarding current practices of monitoring and resuscitating patients with traumatic shock are discussed.

Animals↗