Gag-Protease Sequence Evolution Following Protease Inhibitor Monotherapy Treatment Failure in HIV-1 Viruses Circulating in East Africa.

Around 2.5 million HIV-infected individuals failing first-line therapy qualify for boosted protease inhibitor (bPI)-based second-line therapy globally. Major resistance mutations are rarely present at treatment failure in patients receiving bPI and the determinants of failure in these patients remain unknown. There is evidence that Gag can impact PI susceptibility. Here, we have sequenced Gag-Protease before and following failure in 23 patients in the SARA trial infected with subtypes A, C, and D viruses. Before bPI, significant variation in Protease and Gag was observed at positions previously associated with PI exposure and resistance including Gag mutations L449P, S451N, and L453P and Protease K20I and L63P. Following PI failure, previously described mutations in Protease and Gag were observed, including those at the cleavage sites such as R361K and P453L. However, the emergence of clear genetic determinants of therapy failure across patients was not observed. Larger Gag sequence datasets will be required to comprehensively identify mutational correlates of bPI failure across subtypes

The ‘mosaic habitat’ concept in human evolution: past and present

The habitats preferred by hominins and other species are an important theme in palaeoanthropology, and the ‘mosaic habitat’ (also referred to as habitat heterogeneity) has been a central concept in this regard for the last four decades. Here we explore the development of this concept – loosely defined as a range of different habitat types, such as woodlands, riverine forest and savannah within a limited spatial area– in studies of human evolution in the last sixty years or so. We outline the key developments that took place before and around the time when the term ‘mosaic’ came to wider palaeoanthropological attention. To achieve this we used an analysis of the published literature, a study of illustrations of hominin evolution from 1925 onwards and an email survey of senior researchers in palaeoanthropology and related fields. We found that the term mosaic starts to be applied in palaeoanthropological thinking during the 1970’s due to the work of a number of researchers, including Karl Butzer and Glynn Isaac , with the earliest usage we have found of ‘mosaic’ in specific reference to hominin habitats being by Adriaan Kortlandt (1972). While we observe a steady increase in the numbers of publications reporting mosaic palaeohabitats, in keeping with the growing interest and specialisation in various methods of palaeoenvironmental reconstruction, we also note that there is a lack of critical studies that define this habitat, or examine the temporal and spatial scales associated with it. The general consensus within the field is that the concept now requires more detailed definition and study to evaluate its role in human evolution

Cracking of soft magnetic FeSi to reduce eddy current losses in stator cores

To enable use of additively manufactured (AM) soft magnetic material in electric machines, large bulk cross-sections must be avoided as they allow large eddy currents, reducing efficiency. Fe-6.5 wt%Si is an excellent soft magnetic material, but is brittle. In this study we exploit this inherent characteristic of the material to develop crack networks within the AM material to inhibit parasitic eddy currents. By manipulating the laser parameters and scan strategy to purposefully induce cracking, the effective resistivity of the material can be increased to 206 µΩ·cm, 250% of the materials’ already high resistivity of 82 µΩ·cm. Crack density is shown to increase with decreasing scan speed, and calculated electrical tortuosity shown to correlate with effective resistivity. Different scan strategies are shown to alter the orientation of the cracks, demonstrating that the crack orientation could be controlled in relation to the magnetic flux, providing high electrical resistance in the plane of the eddy currents, whilst maintaining magnetic properties. This method yields losses of 2.2 W/kg at 1 T, 50 Hz, similar to methods using air gaps, but with a much higher stacking factor of > 97%, outperforming other methods used in AM of soft magnetic material, showing promise for manufacturing stators of complex electric machines

Adherence to prescribed antiretroviral therapy in human immunodeficiency virus infected children in the PENTA 5 trial

Background. Most studies of adherence to highly active antiretroviral therapy in children have been retrospective or cross-sectional. Factors relating to the caregiver, the child and the medication are all considered to be important for good adherence. Methods. Adherence with taking prescribed medication was assessed by questionnaires completed at 4, 12, 24 and 48 weeks by caregivers of previously untreated HIV-infected children participating in the PENTA 5 trial, which was designed to evaluate different dual nucleoside reverse transcriptase inhibitor therapy combinations with and without the protease inhibitor nelfinavir. The effects of several factors on adherence and the effect of adherence on virologic suppression were assessed by multivariate logistic regression. Results. Caregivers returned 266 questionnaires including at least 1 for 108 (84%) children in the trial. Nelfinavir was reported to be the most difficult drug to take (38% of questionnaires), but the difficulty decreased over time, P = 0.02. Comments on difficulties in taking and remembering drugs related to fear of disclosure and to unpleasant characteristics of the drugs. Full adherence was reported in 74% of questionnaires, did not change over time and was reported more frequently in children older than 10 years and those with symptomatic HIV disease. More children reporting full adherence achieved HIV RNA <400 copies/ml (e.g. at 48 weeks 79% vs. 50% reporting some nonadherence; overall P = 0.01). Conclusion. Good adherence with taking prescribed medication was associated with virologic response. Social factors were important in explaining nonadherence

Randomised controlled trial and economic evaluation of podophyllotoxin solution, podophyllotoxin cream, and podophyllin in the treatment of genital warts

Objectives: To evaluate the efficacy and cost effectiveness of self applied podophyllotoxin 0.5% solution and podophyllotoxin 0.15% cream, compared to clinic applied 25% podophyllin in the treatment of genital warts over 4 weeks. Methods: We conducted a randomised controlled trial in 358 immunocompetent men and women with genital warts of 3 months’ duration or less. Results: In the principal analysis both podophyllotoxin solution (OR 2.93, 95% CI 1.56 to 5.50) and podophyllotoxin cream (OR 1.97, 95% CI 1.04 to 3.70) were associated with significantly increased odds of remission of all warts compared to podophyllin. We performed two further analyses. When subjects defaulting from follow up were assumed to have been cured odds of remission of all warts were also significantly increased both for podophyllotoxin solution (OR 3.04, 95% CI 1.68 to 5.49) and for podophyllotoxin cream (OR 2.46, 95% CI 1.38 to 4.40). When subjects defaulting from follow up were assumed not to have been cured odds of remission of all warts were significantly increased for podophyllotoxin solution (OR 1.92, 95% CI 1.13 to 3.27), but not for podophyllotoxin cream (OR 1.17, 95% CI 0.69 to 2.00). Local side effects were seen in 24% of subjects, and recurrence of warts within 12 weeks of study entry in 43% of all initially cleared subjects, without statistically significant differences between the treatment groups. Direct, indirect, and total costs were similar across the three treatment groups. Podophyllotoxin solution was the most cost effective treatment, followed by podophyllotoxin cream, with podophyllin treatment being the least cost effective. Conclusions: Self treatment of anogenital warts with podophyllotoxin showed greater efficacy and cost effectiveness than clinic based treatment with podophyllin

Impact of the N348I Mutation in HIV-1 Reverse Transcriptase on Nonnucleoside Reverse Transcriptase Inhibitor Resistance in Non-Subtype B HIV-1▿

We investigated the effect of N348I alone and with M184V on nonnucleoside reverse transcriptase inhibitor (NNRTI) drug susceptibility and replicative capacity in B and non-B HIV-1 isolates. N348I reduced the susceptibility to all NNRTI drugs across subtypes. The replication capacity of all viruses in a variety of cell lines was impaired by N348I. Interestingly, the N348I and M184V double mutation compensated for the reduced NNRTI drug susceptibility observed in the N348I single mutant and marginally improved viral replicative capacity