Neurilemmoma of tongue

Neurilemmoma is usually soimry, benign tumour derived from schwan cells of the Sheaths of peripheral cranial or autonomie nerves. In thehead and neck region it occurs most commonly in association with acoustic nerve within the skuil and is rely fottnd in the oral cavity (1,2). We report here two cases of the iongue diagnosed on histopathohgy.     

Transmission of dengue virus-induced helper signal to B cell via macrophages.

The helper T cells (TH) generated in dengue type 2 virus (DV) infection of mice produce a soluble helper cytokine (HF) which enhances the clonal expansion of DV-specific IgM antibody plaque forming cells (PFC). The present study was undertaken to investigate the mechanism of transmission of the helper signal from TH and HF to B cells. It was observed that TH could transmit the helper signal to B cells by direct cell to cell contact, but HF could not do so without the presence of live macrophages (M phi). HF was adsorbed by both heat killed and live M phi but the former could not transmit it to B cells. Both the polypeptide chains of HF bind to M phi. HF remains on the surface of M phi and can be retrieved completely by contact with B cells for 40 min. The helper signal from TH or HF-adsorbed M phi could not be transmitted to B cells when they were separated from each other by a cell impermeable membrane. The enhancement of PFC count is greater when the signal is transmitted by HF-adsorbed M phi as compared to that by TH alone. Thus, even with lower frequency of TH a significant number of B cells may be triggered with the help of HF and M phi. The findings thus show that the DV-specific helper signal could be transmitted only by a close physical contact of the plasma membranes of the signal presenting cells (TH or HF-adsorbed M phi) and B cells.     

Peritonsillar abscess — Do we need anaerobic cover?

Objective To find out the usability and advantage with regard to the advent of new and more costly antibiotics. In the treatment of Peritonsillar abscess the demonstration of, both aerobic and anaerobic organisms has raised the question of possible need to treat with antibiotics effective against anaerobes. It was in this very context that this study was planned to find out if we still have an economically and easily available antibiotic to treat Peritonsillar abscess. Conclusions Injectable penicillin is the drug of choice in PTA as GABHS and staphylococcus aureus coagulase positive are the most common organism associated with this condition. Even where penicillin resistant organism is present, effective management of the abscess is possible if it is drained well and weak hydrogen peroxide gargles are used along with injectable penicillin.     

Aspiration vs nonaspiration technique of cytodiagnosis--a critical evaluation in 160 cases

The two sampling techniques were studied in 160 randomly selected cases of superficial swellings in various sites of the body. They were sampled by fine needle aspiration (FNA) and by non-aspiration (NA) (a needle without application of aspiration pressure). Cell samples were cytologically assessed and critically evaluated using five objective parameters. Contamination with blood was more in lymphnode, thyroid and liver lesions in aspiration smears than NA smears and values were statistically significant. Similarly when compared for the degree of cellular trauma and cellular degeneration statistically significant better results were obtained by nonaspiration technique for lymphnode lesions. Regarding amount of cellular material obtained by FNA, statistical significant better results were found for breast lesions only. Statistically significant better maintenance of architecture was observed only for thyroid lesions by NA technique. Better average scores were observed by NA technique for lymphnode and thyroid only. Categorizing all the smears obtained by FNA & NA on the basis of their scores according to predetermined criteria, greater number of diagnostically adequate specimens were obtained by FNA than by NA but the number of diagnostically superior specimens obtained by NA technique was found to be more than that by FNA. The difference was found to be statistically significant. However the number of inadequate smears was also more by NA technique than by FNA technique.     

Obligatory role of Ca2+ in the cytotoxic activity of dengue virus-induced cytotoxin.

The role of calcium ions (Ca2+) in the cytotoxic activity of the dengue type 2 virus (DV)-induced macrophage (M phi) cytotoxin (CF2) was investigated in the present study. The findings show that CF2 prepared in Ca(2+)-free medium had no cytotoxic activity on normal mouse spleen cells suspended in Ca(2+)-free medium but killed the cells suspended in the medium with Ca2+. Substitution with calcium chloride restored the cytotoxic activity of CF2 the optimal dose being 10(-4) M concentration. CF2 induced an influx of Ca2+, as assayed by uptake of radiolabelled calcium chloride (45Ca), in the susceptible target cells, viz. M phi and T lymphocytes. The cytotoxic activity of CF2 as well as the CF2-induced influx of 45Ca was inhibited by treatment of the target cell with the calcium channel blocking drugs verapamil and nifedipine. Thus, the presence of Ca2+ is obligatory for the cytotoxic activity of CF2 and cell death is associated with increased intracellular Ca2+.     

Collaborative study of antibiotic medium 3 and flow cytometry for identification of amphotericin B-resistant Candida isolates

Center 1 used the National Committee for Clinical Laboratory Standards M27-A2 method and antibiotic medium 3 (AM3) test to determine amphotericin B resistance in 5 of 30 Candida isolates. These isolates were tested at center 2 by AM3 test and flow cytometry (FC). The agreements (C1-C2) were 90% for AM3 test and FC and 73% for the AM3 tests.