Biomedical subjects
Publications and source records attributed to A Sethi.
Repositioning the inferior alveolar neurovascular bundle is a high risk procedure which can result in permanent damage. It must be justified by the need for posterior mandibular support to stabilize the dentition and provide function. A clinical report is presented.
Explore the source record for details and available documents.
Information gained by preoperative imaging techniques must be accurately related to the surgical site. The inability to do this severely diminishes the benefit of the diagnostic imaging. The CT scan is capable of providing considerable information regarding the jaws. The use of radiopaque markers to identify preselected points on the image is readily done by placing markers in the wax registration rims that are worn during the scan. The position of these markers is transferred to the mouth with a surgical template, facilitating surgery and reducing the incidence of anatomic accidents caused by lack of orientation.
Explore the source record for details and available documents.
Neurocysticercosis was diagnosed in 0.89% of children enrolled in our Child Neurology Clinic in the years 1979 to 1990. The commonest presenting symptom was seizures (90%) followed by raised intracranial pressure (44%). CT scans revealed a variety of lesions including low and high attenuation cysts, periventricular edema, hydrocephalus and calcification. ELISA was useful in substantiating the diagnosis in almost 70% of cases. Only 18 patients who had active disease merited treatment with praziquantel. The clinical and CT response was good. Follow-up revealed spontaneous quiescence in many patients with inactive disease.
Serum samples collected from 45 untreated leprosy patients and 10 healthy subjects were studied for the activities of alkaline phosphatase, N-acetyl beta-glucosaminidase and beta-glucuronidase. A highly significant increase in the specific activity of these enzymes was observed in all types of leprosy patients as compared to controls. Increase in the level of circulatory hydrolytic enzymes could be a tissue damaging factor and may be responsible for many of the lesions seen in leprosy.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The role of a critical care unit in life-threatening situations is well established. The management of 52 children with acute gastroenteritis and 22 children with acute paralytic poliomyelitis as part of recent epidemics is described. The solutions to the problems in the critical care management of these 74 victims (out of a total of 6197 patients admitted during the epidemics) are discussed.
Explore the source record for details and available documents.
The oxygen free radical generation (as determined by cytochrome c reduction) and respiratory burst enzyme activities were measured in the peripheral blood monocytes before infecting normal animals, during primary Plasmodium knowlesi infection, after treatment of primary infection with chloroquine, after administration of various subcurative doses following reinfection and after establishment of chronicity. For all the parameters of the oxidative response, no significant difference was observed during primary infection and after curing of primary infection. However, the response was significantly increased in the reinfected monkeys given subcurative therapy; this was followed by a sharp decline after the 4th subcurative dose, after which the response continued to be low until the attainment of chronicity. The results of the present study exclude the possibility of the increase in oxidative metabolism being the effect of the drug (i.e. chloroquine), since no significant difference was observed during primary infection and after its cure. The sustained low grade parasitaemia in the chronic stage, in spite of the sharp decrease in the oxidative response, suggests that some nonoxidant parasitic killing mechanism might be playing a role in the regulation of parasitaemia.
Human immunodeficiency virus (HIV) often causes latent infection. Transactivation by some DNA viruses has been implicated in inducing HIV-1 replication and pathogenesis. The transactivator (IE-2) gene of the human cytomegalovirus (CMV) can enhance HIV-2 as well as HIV-1 gene expression in vitro. This inducer can act in concert with the HIV-2 tat gene and T-cell activation in enhancing gene expression in human CD4+ lymphocytes. While the HIV-2 and HIV-1 tat genes and T-cell activators apparently employ independent modes of action, the CMV transactivator in combination with the HIV-2 tat or T-cell activators may employ a gene activation pathway with some common and some distinct components. Both HIV-2 and CMV transactivators enhance HIV-2 gene expression by transcriptional activation involving transcript initiation as well as elongation, with CMV transactivator affecting elongation more than the initiation. A significant proportion of transcripts appear to terminate prematurely in the absence of transactivators. Deletion mutation analysis of the HIV-2 long terminal repeat (LTR) suggests that the element that responds to CMV transactivation in human CD4+ lymphocytes is either a diffuse one or located downstream of the HIV-2 enhancer element.
Prostaglandins of the E series have been implicated as possible mediators of thymosin alpha 1 (TA-1) effect on mitogen stimulated lymphoproliferation. In the present study human peripheral blood mononuclear cells were stimulated with concanavalin A in the presence of TA-1, prostaglandin E2 and indomethacin individually, or in combination. Both TA-1 and indomethacin significantly enhanced the proliferative response over that seen with mitogen alone (less than 0.001). The magnitude of enhancement observed with indomethacin (20 microM) was considerably less than that of TA-1 and it was abolished with prostaglandin E2. The combination of indomethacin and TA-1 did not alter TA-1 effect and prostaglandin E2 (up to 250 ng/ml) did not abolish thymosin effect. These results suggest that TA-1 and prostaglandin E2 have opposite effects and that thymosin enhancement of mitogen induced proliferation is not mediated by prostaglandin E2.
Thirty cases of neonatal hyperbilirubinemia of varying etiology, severity and duration; and twenty six normal healthy newborns were subjected to various tests of cellular and humoral immunity. The results revealed a significant depression of all the parameters of cellular immunity in neonatal hyperbilirubinemia of greater than or equal to 10 mg/dl as compared to the control values. The depression of immunological profile in these newborns was seen to be more pronounced with increasing duration and severity of jaundice. A limited assessment of the humoral immunity by the B cell count and serum immunoglobulin IgG levels, however, showed no significant difference from the control.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
An unusual case of Holt-Oram syndrome with arachnodactyly, high arch palate, thoracic scoliosis and hypoplasia of the left radial artery is reported. The relevant literature is discussed and the importance of vascular hypoplasia in genesis and localization of the skeletal deformities of this syndrome is stressed.