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The altruistic act of body donation provides a precious resource for both teaching and researching human anatomy. However, relatively little is known about individuals who donate their bodies to science (donors), and in particular whether donors in different geographical locations share similar characteristics. A multicenter prospective survey of donors registering during 2010 in three different geographical locations, New Zealand, Ireland, and the Republic of South Africa, was conducted to identify donor characteristics. The 28-question survey included sections on body donation program awareness, reasons for donating, giving tendency, education, ethnicity, relationship status, occupation, religion, and political preference. Two hundred surveys (81%) were returned [New Zealand 123 (85% response rate), Republic of South Africa 41 (67%), and Ireland 36 (92%)]. Results indicate that donors share certain characteristics including reason for donating (80% cited a desire to aid medical science as the main reason for wishing to donate their body); family structure (most donors are or have been in long-term partnerships and ≥ 85% have siblings); and a higher proportion with no religious affiliation compared to their reference population. Some variations between locations were noted including donor age, the mode of program awareness, occupation, relationship status, political preference, organ donor status and with whom donors had discussed their decision to donate. This information could be important for assisting the identification of potential body donors in new and established bequest programs.

Rationale-Central dogma suggests that rifampicin resistance in Mycobacterium tuberculosis develops solely through rpoB gene mutations.Objective-To determine whether rifampicin induces efflux pumps activation in rifampicin resistant M. tuberculosis strains thereby defining rifampicin resistance levels and reducing ofloxacin susceptibility.Methods-Rifampicin and/or ofloxacin minimum inhibitory concentrations (MICs) were determined in rifampicin resistant strains by culture in BACTEC 12B medium. Verapamil and reserpine were included to determine their effect on rifampicin and ofloxacin susceptibility. RTqPCR was applied to assess expression of efflux pump/transporter genes after rifampicin exposure. To determine whether verapamil could restore susceptibility to first-line drugs, BALB/c mice were infected with a MDR-TB strain and treated with first-line drugs with/without verapamil. Measurements and Main Findings-RifampicinMICs varied independently of rpoB mutation and genetic background. Addition reserpine and verapamil significantly restored rifampicin susceptibility (p = 0.0000). RT-qPCR demonstrated that rifampicin induced differential expression of efflux/transporter genes in MDR-TB isolates. Incubation of rifampicin monoresistant strains in rifampicin (2 μg/ml) for 7 days induced ofloxacin resistance (MIC> 2 μg/ml) in strains with an rpoB531 mutation. Ofloxacin susceptibility was restored by exposure to efflux pump inhibitors. Studies in BALB/c mice showed that verapamil in combination with first-line drugs significantly reduced pulmonary CFUs after 1 and 2 months treatment (p < 0.05).Correspondence and requests for reprints should be addressed to Robin M. Conclusion-Exposure of rifampicin resistant M. tuberculosis strains to rifampicin can potentially compromise the efficacy of the second-line treatment regimens containing ofloxacin, thereby emphasising the need for rapid diagnostics to guide treatment. Efflux pump inhibitors have the potential to improve the efficacy of anti-tuberculosis drug treatment. KeywordsMycobacterium tuberculosis; drug resistance; rifampicin; efflux pumps; cross resistance Rifampicin is one of the most important anti-tuberculosis (anti-TB) antibiotics; it exerts its bactericidal activity by inhibiting the early steps of gene transcription by binding to the β-subunit of RNA polymerase (RpoB) encoded by the rpoB gene (1). This activity is responsible for shortening the treatment period and reducing the proportion of recurrent TB cases. The currently accepted paradigm suggests that resistance to rifampicin develops through a process of spontaneous mutation (nonsynonymous single nucleotide polymorphisms [nsSNPs]) in the rpoB gene (2), followed by antibiotic selection during periods of poor adherence or monotherapy. Luria-Delbrück fluctuation tests show that rifampicin resistance appears spontaneously at a rate of 10 −9 to 10 −8 mutations per cell division (3, 4). These nsSNPs largely occur in an 81-bp region in the rpoB gene known as the rifampicin resistance-determining region (...

The study of gross Anatomy through the use of cadaveric dissections in medical schools is an essential part of the comprehensive learning of human Anatomy, and unsurprisingly, 90% of the surveyed medical schools in Africa used cadaveric dissections. Donated cadavers now make up 80% of the total cadavers in North American medical schools and all the cadavers used for dissection in the United Kingdom are donated. Because the sources of cadavers used in Africa are not clearly known, a questionnaire to gather information on cadavers used at medical schools was designed from the relevant literature and was sent by electronic mail to 123 Anatomy lecturers in 23 African countries (48 medical schools). Fourteen lecturers from 14 medical schools in ten countries responded to the questionnaires. The results indicate that, in most countries, the cadavers are unclaimed bodies from the hospitals and prisons, and the bodies of dead bandits. In South Africa and Zimbabwe, the donations are mostly from the white community, and medical school in the Islamic country of Libya is importing cadavers from India. The lack of knowledge about body donation programes and firmly held cultural and religious burial traditions may explain the lack of bequests from black communities. The use of unclaimed bodies may disproportionally affect people who were homeless and poor, criminals, people with fewer social links, and social outcasts. The Anatomy lecturers felt that there should be broader national awareness programes for body donations, although the benefits of this could take decades to materialize.

This Guide, a combined work by three authors from different countries, provides perspectives into the history of teaching gross anatomy, briefly, from the earliest of times, through to a detailed examination of curricula in both traditional didactic approaches and Problem-Based Learning (PBL) curricula. The delivery of a module within a curriculum in tertiary education is interplay between the content (knowledge and skills) of a subject, the teaching staff involved, the students and their approaches to learning, and the philosophy underpinning the delivery of the learning material. The work is divided into sections that deal with approaches to learning anatomy from the perspective of students, to delivery of the content of the curriculum by lecturers, including the assessment of knowledge, and itemises the topics that could be considered important for an appropriate anatomy module in an integrated course, delivered in a way that emphasises clinical application. The work concludes by looking to the future, and considering what measures may need to be addressed to ensure the continued development of anatomy as a clinically relevant subject in any medical curriculum.

cThe inherent drug susceptibility of microorganisms is determined by multiple factors, including growth state, the rate of drug diffusion into and out of the cell, and the intrinsic vulnerability of drug targets with regard to the corresponding antimicrobial agent. Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), remains a significant source of global morbidity and mortality, further exacerbated by its ability to readily evolve drug resistance. It is well accepted that drug resistance in M. tuberculosis is driven by the acquisition of chromosomal mutations in genes encoding drug targets/promoter regions; however, a comprehensive description of the molecular mechanisms that fuel drug resistance in the clinical setting is currently lacking. In this context, there is a growing body of evidence suggesting that active extrusion of drugs from the cell is critical for drug tolerance. M. tuberculosis encodes representatives of a diverse range of multidrug transporters, many of which are dependent on the proton motive force (PMF) or the availability of ATP. This suggests that energy metabolism and ATP production through the PMF, which is established by the electron transport chain (ETC), are critical in determining the drug susceptibility of M. tuberculosis. In this review, we detail advances in the study of the mycobacterial ETC and highlight drugs that target various components of the ETC. We provide an overview of some of the efflux pumps present in M. tuberculosis and their association, if any, with drug transport and concomitant effects on drug resistance. The implications of inhibiting drug extrusion, through the use of efflux pump inhibitors, are also discussed.

The emergence of drug resistance continues to plague TB control, with a global increase in the prevalence of MDR-TB. This acts as a gateway to XDR-TB and thus emphasizes the urgency for drug development and optimal treatment options. Bedaquiline is the first new anti-TB drug approved by the FDA in 40 years and has been shown to be an effective treatment option for MDR Mycobacterium tuberculosis infection. Bedaquiline has also recently been included in clinical trials for new regimens with the aim of improving and shortening treatment periods. Alarmingly, efflux-mediated bedaquiline resistance, as well as efflux-mediated cross-resistance to clofazimine, has been identified in treatment failures. This mechanism of resistance results in efflux of a variety of anti-TB drugs from the bacterial cell, thereby decreasing the intracellular drug concentration. In doing so, the bacillus is able to render the antibiotic treatment ineffective. Recent studies have explored strategies to reverse the resistance phenotype conferred by efflux pump activation. It was observed that the addition of efflux pump inhibitors partially restored drug susceptibility in vitro and in vivo. This has significant clinical implications, especially in MDR-TB management where treatment options are extremely limited. This review aims to highlight the current efflux pump inhibitors effective against M. tuberculosis, the effect of efflux pump inhibitors on mycobacterial growth and the clinical promise of treatment with efflux pump inhibitors and standard anti-TB therapy.

BackgroundWhole genome sequencing has revolutionised the interrogation of mycobacterial genomes. Recent studies have reported conflicting findings on the genomic stability of Mycobacterium tuberculosis during the evolution of drug resistance. In an age where whole genome sequencing is increasingly relied upon for defining the structure of bacterial genomes, it is important to investigate the reliability of next generation sequencing to identify clonal variants present in a minor percentage of the population. This study aimed to define a reliable cut-off for identification of low frequency sequence variants and to subsequently investigate genetic heterogeneity and the evolution of drug resistance in M. tuberculosis. MethodsGenomic DNA was isolated from single colonies from 14 rifampicin mono-resistant M. tuberculosis isolates, as well as the primary cultures and follow up MDR cultures from two of these patients. The whole genomes of the M. tuberculosis isolates were sequenced using either the Illumina MiSeq or Illumina HiSeq platforms. Sequences were analysed with an in-house pipeline.ResultsUsing next-generation sequencing in combination with Sanger sequencing and statistical analysis we defined a read frequency cut-off of 30 % to identify low frequency M. tuberculosis variants with high confidence. Using this cut-off we demonstrated a high rate of genetic diversity between single colonies isolated from one population, showing that by using the current sequencing technology, single colonies are not a true reflection of the genetic diversity within a whole population and vice versa. We further showed that numerous heterogeneous variants emerge and then disappear during the evolution of isoniazid resistance within individual patients. Our findings allowed us to formulate a model for the selective bottleneck which occurs during the course of infection, acting as a genomic purification event.ConclusionsOur study demonstrated true levels of genetic diversity within an M. tuberculosis population and showed that genetic diversity may be re-defined when a selective pressure, such as drug exposure, is imposed on M. tuberculosis populations during the course of infection. This suggests that the genome of M. tuberculosis is more dynamic than previously thought, suggesting preparedness to respond to a changing environment.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-015-2067-2) contains supplementary material, which is available to authorized users.