Effect of multiple intervention models on uptake of HIV testing services and sexual behaviour among residents of military cantonments in south-east Nigeria

Background: HIV testing and counselling (HTC) has been a viable tool in controlling the spread of HIV/AIDS, and serves as the entry point in the HIV care and treatment cascade. In Africa, HIV-related morbidity and mortality are high with thousands still unaware of their HIV status. This study assessed the effect of on-site multiple HIV control interventions on the uptake of HTC services, knowledge and sexual behaviour among residents of two military cantonments [barracks] in south-east Nigeria. Methods: A quasi-experimental study was conducted among residents of cantonments in two states in Nigeria. A multistage sampling technique was used to select 350 respondents each at intervention and control sites. A pre-tested interviewer-administered questionnaire was used to collect information. On-site HTC services were established, with the training of HTC counsellors and peer educators. HIV awareness carnivals, with information, education and communication activities were conducted. Data were analysed with SPSS software and statistical tests carried out at 5% level of significance. Results: There was a statistically significant increase in the uptake of HTC services from 41.1% pre-intervention to 81.1% post-intervention (χ² = 113.8, p < 0.001). Also, knowledge about HIV improved significantly from 35.4% to 98.8% (p < 0.001) in the intervention group, together with avoidance of risky sexual behaviour. Conclusion: The study demonstrated the effectiveness of multiple on-site intervention models in improving HIV knowledge, uptake of HTC services, and sexual behaviour among diverse cantonment residents. Establishing on-site HTC services and a constellation of awareness events will contribute significantly towards HIV prevention and control among high-risk populations.

Pathogenic Escherichia coli Strains Recovered from Selected Aquatic Resources in the Eastern Cape, South Africa, and Its Significance to Public Health

The prevalence of pathogenic microorganisms, as well as the proliferation of antimicrobial resistance, pose a significant threat to public health. However, the magnitude of the impact of aquatic environs concerning the advent and propagation of resistance genes remains vague. Escherichia coli (E. coli) are widespread and encompass a variety of strains, ranging from non-pathogenic to highly pathogenic. This study reports on the incidence and antibiotic susceptibility profiles of E. coli isolates recovered from the Nahoon beach and its canal waters in South Africa. A total of 73 out of 107 (68.2%) Polymerase chain reaction confirmed E. coli isolates were found to be affirmative for at least one virulence factor. These comprised of enteropathogenic E. coli 11 (10.3%), enteroinvasive E. coli 14 (13.1%), and neonatal meningitis E. coli 48 (44.9%). The phenotypic antibiogram profiles of the confirmed isolates revealed that all 73 (100%) were resistant to ampicillin, whereas 67 (91.8%) of the pathotypes were resistant to amikacin, gentamicin, and ceftazidime. About 61 (83.6%) and 51 (69.9%) were resistant to tetracycline and ciprofloxacin, respectively, and about 21.9% (16) demonstrated multiple instances of antibiotic resistance, with 100% exhibiting resistance to eight antibiotics. The conclusion from our findings is that the Nahoon beach and its canal waters are reservoirs of potentially virulent and antibiotic-resistant E. coli strains, which thus constitute a potent public health risk.

Characterization of muscle ankyrin repeat proteins in human skeletal muscle

Muscle ankyrin repeat proteins (MARPs) are a family of titin-associated, stress-response molecules and putative transducers of stretch-induced signaling in skeletal muscle. In cardiac muscle, cardiac ankyrin repeat protein (CARP) and diabetes-related ankyrin repeat protein (DARP) reportedly redistribute from binding sites on titin to the nucleus following a prolonged stretch. However, it is unclear whether ankyrin repeat domain protein 2 (Ankrd 2) shows comparable stretch-induced redistribution to the nucleus. We measured the following in rested human skeletal muscle: 1) the absolute amount of MARPs and 2) the distribution of Ankrd 2 and DARP in both single fibers and whole muscle preparations. In absolute amounts, Ankrd 2 is the most abundant MARP in human skeletal muscle, there being ~3.1 µmol/kg, much greater than DARP and CARP (~0.11 and ~0.02 µmol/kg, respectively). All DARP was found to be tightly bound at cytoskeletal (or possibly nuclear) sites. In contrast, ~70% of the total Ankrd 2 is freely diffusible in the cytosol [including virtually all of the phosphorylated (p)Ankrd 2-Ser99 form], ~15% is bound to non-nuclear membranes, and ~15% is bound at cytoskeletal sites, likely at the N2A region of titin. These data are not consistent with the proposal that Ankrd 2, per se, or pAnkrd 2-Ser99 mediates stretch-induced signaling in skeletal muscle, dissociating from titin and translocating to the nucleus, because the majority of these forms of Ankrd 2 are already free in the cytosol. It will be necessary to show that the titin-associated Ankrd 2 is modified by stretch in some as-yet-unidentified way, distinct from the diffusible pool, if it is to act as a stretch-sensitive signaling molecule.

Identification and antimicrobial resistance prevalence of pathogenic Escherichia coli strains from treated wastewater effluents in Eastern Cape, South Africa

Antimicrobial resistance (AMR) is a global problem impeding the effective prevention/treatment of an ever-growing array of infections caused by pathogens; a huge challenge threatening the achievements of modern medicine. In this paper, we report the occurrence of multidrug resistance (MDR) in Escherichia coli strains isolated from discharged final effluents of two wastewater treatment facilities in the Eastern Cape Province of South Africa. Standard disk diffusion method was employed to determine the antibiotic susceptibility profile of 223 polymerase chain reaction (PCR)-confirmed E. coli isolates against 17 common antibiotics in human therapy and veterinary medicine. Seven virulence associated and fourteen antibiotic resistance genes were also evaluated by molecular methods. Molecular characterization revealed five pathotypes of E. coli in the following proportions: enterotoxigenic ETEC (1.4%), enteropathogenic EPEC (7.6%), enteroaggregative EAEC (7.6%), neonatal meningitis (NMEC) (14.8%), uropathogenic (41.7%), and others (26.9%). Isolates showed varying (1.7-70.6%) degrees of resistance to 15 of the test antibiotics. Multidrug resistance was exhibited by 32.7% of the isolates, with the commonest multiple antibiotic-resistant phenotype (MARP) being AP-T-CFX (12 isolates), while multiple antibiotic-resistant indices (MARI) estimated are 0.23 (Site 1) and 0.24 (Site 2). Associated antibiotic resistance genes detected in the isolates include: strA (88.2%), aadA (52.9%), cat I (15%), cmlA1 (4.6%), blaTEM (56.4%), tetA (30.4%), tetB (28.4%), tetC (42.2%), tetD (50%), tetK (11.8%), and tetM (68.6%). We conclude that municipal wastewater effluents are important reservoirs for the dissemination of potentially pathogenic E. coli (and possibly other pathogens) and antibiotic resistance genes in the aquatic milieu of the Eastern Cape and a risk to public health.

Probing muscle ankyrin-repeat protein (MARP) structure and function

Muscle ankyrin-repeat proteins (MARPs) have been shown to serve diverse functions within cardiac and skeletal muscle cells. Apart from their interactions with sarcomeric proteins like titin or myopalladin that locate them along myofilaments, MARPs are able to shuttle to the nucleus where they act as modulators for a variety of transcription factors. The deregulation of MARPs in many cardiac and skeletal myopathies contributes to their use as biomarkers for these diseases. Many of their functions are attributed to their domain composition. MARPs consist of an N-terminal coiled-coil domain responsible for their dimerization. The C-terminus contains a series of ankyrin repeats, whose best-characterized function is to bind to the N2A region of the giant sarcomeric protein titin. Here we investigate the nature of their dimerization and their interaction with titin more closely. We demonstrate that the coiled-coil domain in all MARPs enables their homo- and hetero-dimerization in antiparallel fashion. Protein complementation experiments indicate further antiparallel binding of the ankyrin repeats to titin's N2A region. Binding of MARP to titin also affects its PKA mediated phosphorylation. We demonstrate further that MARPs themselves are phosphorylated by PKA and PKC, potentially altering their structure or function. These studies elucidate structural relationships within the stretch-responsive MARP/titin complex in cross-striated muscle cells, and may relate to disease relevant posttranslational modifications of MARPs and titin that alter muscle compliance.