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Cyclophilin appears to participate in the reproduction of HIV. Cyclophilin is a enzyme in human cells. It is believed to cut the p24 viral peptide by removing p17. Researchers measured the ability of cyclophilin to bind to various viral proteins. The enzyme became more strongly bound to the p24 protein when it contained the p17 amino acid sequence than it did to the p24 protein alone. This confirms that the enzyme binds to the p17-p24 amino acid sequence and then removes the p17 sequence. This step occurs when the virus reproduces.

Sequential sera from 48 subjects infected with human immunodeficiency virus type I (HIV-I) were examined over 36 months for the presence of neutralising antibodies, and for specific anti-gag(p24) and anti-env(gp41) antibodies to HIV-I. Results were interpreted in terms of clinical outcome during the period 1982/3 to 1985/6. HIV-I-infected subjects who remained symptom-free, by comparison with those who manifested AIDS or AIDS-related complex (ARC), had a significantly higher titre of anti-p24 antibodies throughout the 3 years, as measured by competitive enzyme-linked immunosorbent assay and radioimmunoprecipitation. The symptomless subjects also showed a trend towards an increasing neutralising antibody titre with time. There was no relation between anti-gp41 titre and clinical outcome, nor an independent relation between anti-p24 and neutralising titre. A lower or falling titre of anti-p24 antibody was associated significantly with clinical progression, up to 27 months before development of AIDS/ARC.

Summary: A micropropagation protocol for Artocarpus altilis (breadfruit, yellow cultivar) using shoot tip explants taken from mature trees is outlined. Cultures were initiated from shoot tip explants (1–2 mm in length) on either N5K or N15K (Margara, 1978) macronutrient formulation, MS (Murashige and Skoog, 1962) micronutrients and vitamins and 6-benzyladenine (BA, 4.4 μM). Single-node explants obtained from shoots formed at the initiation stage were used at the multiplication stage. Multiplication elongation and maintenance were possible on N30NH4 (Margara, 1978) macronutrients, MS micronutrients and vitamins and zeatin 2.2 μM. Shoot elongation was not enhanced by the inclusion of gibberelic acid at 1.4 μM, 2.8 μM or 14.0 μM, along with zeatin at 2.2 μM, when compared with those shoots cultured on zeatin only. N30NH4 was found to be superior (with respect to shoot quality) to MS macronutrient formulations at the multiplication and maintenance stages, because the shoots with development were more vigorous than those formed on the other macronutrient formulations mentioned. Zeatin at 2.2 μM yielded 50% more in vitro-formed shoots when compared with BA at 4.4 μM for the same time period. Shoots rooted on hormone-free medium with a success rate of 60%. Regenerated plantlets were hardened with about a 40% success rate.

Presents letters to the editor referencing articles and topics discussed in previous issues. Reaction to the statement of President Calvin Coolidge at the World Economic Conference that tariff barriers did not apply to the U.S.; Reaction to the increasing Asian immigration to the U.S.