Vicharn Vithayasai

Clinical Manifestations of 174 AIDS Cases in Maharaj Nakorn Chiang Mai Hospital

The human immunodeficiency virus (HIV) has, since it was first reported in 1981, become a worldwide epidemic. The immunosuppressive nature of HIV results in opportunistic infections, neoplasms, and other pathological conditions. Clinical manifestations of these conditions are often the first indication that an individual is infected with HIV. This article reports and describes the clinical findings for 174 HIV-positive patients and is intended to educate Thai physicians concerning the rising HIV infection rate in Thailand. The opportunistic infectious agents included fungal, parasitic, viral, and bacterial organisms. Cryptococcosis, penicillosis, candidiasis, and histoplasmosis are fungal diseases which are discussed. Protozoal organisms and diseases covered are Pneumocystis carinii, toxoplasmosis, cryptosporidiosis, isosporiosis, and Demodex folliculorum. Bacterial infections addressed are tuberculosis, syphilis, and salmonellosis. The parasite causing nocardiosis is also discussed. Viral infections addressed are cytomegalovirus infection, herpes simplex, and hairy leukoplakia. Neoplasms or tumors discussed are Kaposis sarcoma and non-Hodgkins lymphoma. Other pathological conditions described are brain atrophy, HIV retinopathy, and HIV wasting syndrome. In most cases, a suggested therapy regime is given for the condition discussed.

Human Immunodeficiency Virus Type 1 Subtype E Envelope Recombinant Peptides Containing Naturally Immunogenic Epitopes

A series of recombinant peptides of the human immunodeficiency virus type 1 (HIV-1) subtype E envelope were used to address the question of whether immunogenic epitopes similar to those described for the subtype B envelope are also present in structurally analogous regions of another HIV-1 subtype with divergent sequences. Five recombinant peptides, covering the V2 and V3 domains of gp120, the cysteine-loop region of gp41, a gp41 region involved in oligomerization, and the cytoplasmic tail of gp41, were found to react with >50% of the serum samples analyzed. All but the V2 region in the HIV-1 subtype B envelope have been reported to contain continuous epitopes that are highly immunogenic during natural infection. This finding suggests that, despite the sequence divergence between subtype E and B envelopes, most of the continuous epitopes that are highly immunogenic during natural infection are located at structurally analogous regions of the envelope.

Effect of Histamine and Antihistamines on Interleukin-1 Production by Human Monocytes

This study was carried out on the effect of histamine hydrochloride and its antagonists on the production of interleukin‐1 (IL‐1) by lipopolysaccharide (LPS)‐stimulated adherent human monocytes (AHM) from normal healthy blood donors. IL‐1 activity was evaluated by incorporation of [3H]‐thymidine in mouse thymocytes in samples of 1:3 dilution. The result indicated that histamine hydrochloride significantly suppressed IL‐1 production by AHM at 10−3 m and 10−10 m in 14 donors with maximal suppression observed at 10−3 m. A 1‐hr incubation with histamine hydrochloride (10−3 m) before addition of LPS was found to be appropriate. Cimetidine, an H2‐antagonist at 10−3 m, 10−5 m, and 10−7 m significantly inhibited the effect of histamine hydrochloride (10−3 m) and gave maximum inhibition at 10−5 m, whereas chlorpheniramine maleate, and H1‐antagonist had no significant inhibitory effect at the concentrations studied (10−4 m, 10−5 m, and 10−7 m). Histamine hydrochloride (10−3 m) added alone had no significant suppressive effect, while cimetidine (10−5 m) alone had a significant stimulatory effect on IL‐1 production by AHM.

Letter to the editor of the NEJM

Recommendations from the meeting on prevention of mother-to-infant transmission of HIV by the use ofantiretrovirals. World Health Organization. Geneva, 1994. International Ethical Guidelines for Biomedical Research Involving Human Subjects. Council for International Organizations of Medical Sciences and the World Health Organisation. Geneva, 1993. Halsey NA, Sommer A, Henderson DA et al, 1997. Ethics and international research (editorial). BMJ. 3157114. Prabhakaran S, 1997. Mothers give support to placebo trials. Mail and Guardian. 1 October, Johannesburg.

A pre-amplified reverse hemolytic plaque assay

A pre-amplified reverse hemolytic plaque assay has been developed. Sheep red blood cells (SRBC) were coated with staphylococcal protein A (SPA) by the chromic chloride method. The protein A-coated SRBC (SPA-SRBC) was then pre-amplified with an appropriate amount of human class-specific Ig. The pre-amplified Ig-SPA-SRBC was used to detect class-specific Ig-producing cells. It was found that this pre-amplified reverse hemolytic plaque assay gave clearer, larger and more numerous hemolytic plaques which were easy to count and thus gave more accurate results.