The public health response to the re-emergence of syphilis in Wales, UK

During the 1990s, cases of infectious syphilis were uncommon in Wales. In 2002, an outbreak occurred in a sexual network of men who have sex with men (MSM) attending a sauna. A multidisciplinary outbreak control team was convened to raise awareness of the outbreak among MSM and health professionals, assess the extent of outbreak, and initiate surveillance measures. It is likely that early intensive control efforts dampened the epidemic curve. However, since 2006 the number of cases has increased steadily to a peak of four cases per 100,000 population in 2008. The majority of cases continue to occur in MSM (81% in 2009) and in those attending genitourinary (GU) medicine clinics in south east Wales (76%). Traditional sexual networks such as saunas, bars/clubs and cruising grounds remain frequently reported, but Internet-based networks are assuming increasing importance. Public health interventions have been sustained, using traditional partner notification, health promotion initiatives, and more innovative Internet network tracing methods.

Audit of a network of sexually transmitted infections centred in South Wales

The aim of this article is to audit the distribution and frequency of sexually transmitted infections (STIs) within a sexual network centred in South Wales. After diagnosis of a new case of HIV in February 2007, partner notification, HIV and STI testing were undertaken. Those traced were given information regarding safe sex practices and informed they had been in contact with HIV. Genitourinary (GU) medicine case-notes of contacts identified in the network were reviewed from February 2007 to 1 July 2008. Frequency and distribution of new diagnoses of STIs made on original identification in the network in 2007 were compared with subsequent new diagnoses within the network. One hundred and eighteen men who have sex with men (MSMs) and five women were identified in the original network in 2007. By 1 July 2008, 65 new sexual contacts (all MSMs) were added to the network and there were 25 new STI diagnoses in 13 contacts. Seven contacts originally identified in the cluster in 2007 were diagnosed with 16 of the new STIs. In conclusion, the sexual network has evolved by increasing in size with multiple new STIs diagnosed. The highest risk of STIs occurred in relatively few individuals. Standard interventions in health promotion in the GU medicine setting were not universally successful in preventing high-risk behaviour.

Investigation of an HIV transmission cluster centred in South Wales

OBJECTIVE

To describe an HIV transmission cluster centred in South Wales by the analysis of partner notification outcomes and demographic characteristics of individuals identified in the sexual network.

METHODS

After diagnosis of the index case, HIV testing and partner notification were undertaken by Cardiff Genitourinary Medicine Clinic in collaboration with the local Health Protection Team, National Public Health Service for Wales and Terrence Higgins Trust Cymru. Rapid test and standard venepuncture methods were used for HIV screening and the resulting clinical and behavioural data were analysed.

RESULTS

Of the 123 individuals identified in the sexual network, all were men who had sex with men (MSM) except for seven men who self-identified as bisexual and five heterosexual women. Fifteen new cases of HIV were diagnosed; all were men. Partner notification outcomes are as follows: 104 provider referrals were made, 57 were successfully contacted with known outcomes, 14 were successfully contacted but with unknown outcomes and 33 were uncontactable. Fifteen patient referrals were made, 11 had known outcomes but four had unknown outcomes. Four patients self-referred. Eleven reported previous HIV diagnosis. The sexual network was distributed over South and West Wales extending into England, with high reported rates of unprotected anal intercourse, previous HIV tests and concurrent sexually transmitted infections. A one in four positive rate for those with a known HIV status outcome and a 68% provider referral success rate compares favourably with other studies.

CONCLUSIONS

Partner notification revealed a relatively young, well-educated HIV network with high-risk behaviour and ongoing transmission despite previous knowledge and awareness of HIV. This analysis adds to the evidence supporting HIV partner notification in MSM.

Discovery of macrocyclic hydroxamic acids containing biphenylmethyl derivatives at P1', a series of selective TNF-alpha converting enzyme inhibitors with potent cellular activity in the inhibition of TNF-alpha release

SAR exploration at P1' using an anti-succinate-based macrocyclic hydroxamic acid as a template led to the identification of several bulky biphenylmethyl P1' derivatives which confer potent porcine TACE and anti-TNF-alpha cellular activities with high selectivity versus most of the MMPs screened. Our studies demonstrate for the first time that TACE has a larger S1' pocket in comparison to MMPs and that potent and selective TACE inhibitors can be achieved by incorporation of sterically bulky P1' residues.

Design, synthesis, and structure-activity relationships of macrocyclic hydroxamic acids that inhibit tumor necrosis factor alpha release in vitro and in vivo

To search for TNF-alpha (tumor necrosis factor alpha) converting enzyme (TACE) inhibitors, we designed a new class of macrocyclic hydroxamic acids by linking the P1 and P2' residues of acyclic anti-succinate-based hydroxamic acids. A variety of residues including amide, carbamate, alkyl, sulfonamido, Boc-amino, and amino were found to be suitable P1-P2' linkers. With an N-methylamide at P3', the 13-16-membered macrocycles prepared exhibited low micromolar activities in the inhibition of TNF-alpha release from LPS-stimulated human whole blood. Further elaboration in the P3'-P4' area using the cyclophane and cyclic carbamate templates led to the identification of a number of potent analogues with IC(50) values of </=0.2 microM in whole blood assay (WBA). Although the P3' area can accommodate a broad array of structurally diversified functional groups including polar residues, hydrophobic residues, and amino and carboxylic acid moieties, in both the cyclophane series and the cyclic carbamate series, a glycine residue at P3' was identified as a critical structural component to achieve both good in vitro potency and good oral activity. With a glycine residue at P3', an N-methylamide at P4' provided the best cyclophane analogue, SL422 (WBA IC(50) = 0.22 microM, LPS-mouse ED(50) = 15 mg/kg, po), whereas a morpholinylamide at P4' afforded the most potent and most orally active cyclic carbamate analogue, SP057 (WBA IC(50) = 0.067 microM, LPS-mouse ED(50) = 2.3 mg/kg, po). Further profiling for SL422 and SP057 showed that these macrocyclic compounds are potent TACE inhibitors, with K(i) values of 12 and 4.2 nM in the porcine TACE assay, and are broad-spectrum MMP inhibitors. Pharmacokinetic studies in beagle dogs revealed that SL422 and SP057 are orally bioavailable, with oral bioavailabilities of 11% and 23%, respectively.

Synthesis and antiplatelet effects of an isoxazole series of glycoprotein IIb/IIIa antagonists

Despite the excellent in vitro potency of a series of benzamide glycoprotein IIb/IIIa antagonists, which have been reported previously, poor in vivo potency in the inhibition of platelet aggregation was observed when the most potent inhibitor XU057 was dosed intravenously to dogs. In this communication, we report that replacement of the benzamide in XU057 with an isoxazolecarboxamide resulted in significant improvement in in vivo potency. More importantly, the analogue XU065 showed an excellent oral antiplatelet effect in dogs.

Design, synthesis, and in vitro activities of benzamide-core glycoprotein IIb/IIIa antagonists: 2,3-diaminopropionic acid derivatives as surrogates of aspartic acid

In an effort to discover novel nonpeptide glycoprotein IIb/IIIa (GPIIb/IIIa, alpha IIb/beta 3) inhibitors, we investigated RGD mimetics featuring a 3-substituted benzoic acid as the core, benzamidine as the basic moiety, and a series of beta- and alpha-substituted beta-alanine derivatives as aspartic acid surrogates. It was found that the use of beta-methyl beta-alanine slightly improved the anti-aggregant potency in human platelet-rich plasma over the unsubstituted beta-alanine compound, while beta-substitution with a trifluoromethyl group resulted in considerable loss in activity. Significant enhancement (up to 100-fold) in potency was obtained when the beta-alanine was replaced with N2-substituted 1-2,3-diaminopropionic acid derivatives. Among the three types of alpha-substituents (carbamate, amide, and sulfonamide) investigated, no apparent preference was observed with respect to in vitro potency. However, alkyl groups were more favorable than arylalkyl groups (Cbz) in the carbamate analogues. We also investigated piperidine, piperazine, and N-formamidinopiperidine as replacements for the benzamidine moiety. The former two replacements led to a drop in potency while the latter replacement resulted in maintenance of activity as compared with the corresponding benzamidine analogue.