High-risk sexual behaviours among drug users in Pakistan: implications for prevention of STDs and HIV/AIDS.

Our objective was to describe HIV/STD risk behaviours and awareness among a community-based sample of drug users in Pakistan. Drug users contacted through street outreach by a non-governmental organization in Quetta, Peshawar and Rawalpindi underwent interviewer-administered questionnaires. Descriptive statistics were used to characterize sexual behaviours by city, marital status and the use of injection drugs. Logistic regression was used to identify correlates of ever having an STD. Of 608 drug users studied, all but one was male; median age was 32 years and 45% had no formal education. Half were married, of whom 25% were living with their wives. Sexual behaviours were reported as follows: 14% had sex with other males, 28% reported sex with males and females, 49% had paid money to have sex and only 10% had ever used condoms. One-fifth reported having had an STD and about 40% reported having suffered from either one or more STD-related symptoms. Only 41% had heard about HIV/AIDS, of whom 17% knew that HIV/AIDS could be transmitted through sexual contact. In conclusion, high-risk sexual behaviours are prevalent among male drug users in Pakistan, and awareness of transmission risks is low. These data attest to the urgent need for effective and specific interventions in Pakistan to prevent transmission of HIV and STDs among drug users and their sex partners (I J STD & AIDS 2004;15:601-7).

High-risk sexual behaviours among drug users in Pakistan: implications for prevention of STDs and HIV/AIDS.

Our objective was to describe HIV/STD risk behaviours and awareness among a community-based sample of drug users in Pakistan. Drug users contacted through street outreach by a non-governmental organization in Quetta, Peshawar and Rawalpindi underwent interviewer-administered questionnaires. Descriptive statistics were used to characterize sexual behaviours by city, marital status and the use of injection drugs. Logistic regression was used to identify correlates of ever having an STD. Of 608 drug users studied, all but one was male; median age was 32 years and 45% had no formal education. Half were married, of whom 25% were living with their wives. Sexual behaviours were reported as follows: 14% had sex with other males, 28% reported sex with both males and females, 49% had paid money to have sex and only 10% had ever used condoms. One-fifth reported having had an STD and about 40% reported having suffered from either one or more STD-related symptoms. Only 41% had heard about HIV/AIDS, of whom 17% knew that HIV/AIDS could be transmitted through sexual contact. In conclusion, high-risk sexual behaviours are prevalent among male drug users in Pakistan, and awareness of transmission risks is low. These data attest to the urgent need for effective and specific interventions in Pakistan to prevent transmission of HIV and STDs among drug users and their sex partners.

Mechanism of action of monoketo-organomycin, cystaurimycin and their performic acid-oxidized modifications. I. Effects on bacterial growth and ribosomal peptidyl transferase activity.

The response of 15 bacterial cultures to the inhibitory effects of the above mentioned compounds was investigated. These varied considerably. Escherichia coli cultures resistant to the compounds tested showed that monoketo-organomycin and cystaurimycin inhibit bacterial growth by what appears to be the one and same mechanism which is not the same as that exhibited by their performic acid-oxidized modifications. This was confirmed by using cell free extracts of E. coli. In light of the puromycin reaction, using chloramphenicol and chlorotetracycline as control inhibitors, monoketo-organomycin and cystaurimycin were found to inhibit protein synthesis in vitro by inhibiting peptidyl transferase of ribosomes. In marked contrast, this enzyme was activated, as also was protein synthesis, by their performic acid-oxidized modifications. It was thus suggested that the growth inhibitory effects of the latter compounds might be due to their interference in other metabolic activities of the above test organism. The results obtained are discussed in light of the chemical similarities or differences existing between the compounds investigated.

Mitochondrial ATPase complex of Aspergillus nidulans and the dicyclohexylcarbodiimide-binding protein.

The dicyclohexylcarbodiimide-binding protein of Aspergillus nidulans has been identified as the smallest subunit of the mitochondrial ATPase complex, and has a molecular weight of approximately 8000. It is extractable from whole mitochondria and from the purified enzyme in neutral chloroform/methanol, contains 30% polar amino acids, and the N-terminal amino acid has been identified as tyrosine. Using a double-labelling technique in the absence and presence of cycloheximide, followed by immunoprecipitation of the enzyme complex with antiserum against Neuospora crassa F1 ATPase, it has been shown that this subunit is synthesized on cytoplasmic ribosomes.

Further studies on ASN-136 and monoketo-organomycin cystaurimycin, a broad spectrum substance produced by partial enzymic digestion of monoketo-organomycin.

The two antibiotics ASN-136 and monoketo-organomycin (MKOM) showed very close similarities in their UV, IR spectra and elemental analysis to those of tuberactinomycin and yazumycin respectively. Further chemical and enzymic studies revealed the novelty of the two former antibiotics. Partial enzymic hydrolysis of MKOM yielded a hydrolytic product of more potent inhibitory action compared with the parent antibiotic. Having cystine as the N-terminus and taurine as the C-terminus in its molecule, this enzymic degradation product was designated cystaurimycin. Performic acid oxidation of MKOM and of cystaurimycin improved their growth inhibitory effects on the test organisms used.

Biological breakdown of benzylpenicillin by preformed mats of penicillin-producing organisms.

1. Penicillium chrysogenum and Aspergillus flavus degraded benzylpenicillin in the same way. 2. Degradation of the antibiotic was initiated by the cleavage of phenylacetic acid from 6-aminopenicillanic acid. 3. Phenylacetic acid was left unchanged whereas 6-aminopenicillanic acid was degraded into cysteine and valine. This reaction is probably complex. 4. Cysteine was not utilized but valine was cleaved into acetone and glycine. Catabolism of valine by the preformed mats of the two moulds confirms this result. This step probably involves the formation of propan-2-ol. 5. Cleavage of benzylpenicillin into phenylacetic acid and 6-aminopenicillanic acid was performed through the activity of a cellular-bound enzyme.