Deciphering the growth behaviour of Mycobacterium africanum.

BACKGROUND: Human tuberculosis (TB) in West Africa is not only caused by M. tuberculosis but also by bacteria of the two lineages of M. africanum. For instance, in The Gambia, 40% of TB is due to infections with M. africanum West African 2. This bacterial lineage is associated with HIV infection, reduced ESAT-6 immunogenicity and slower progression to active disease. Although these characteristics suggest an attenuated phenotype of M. africanum, no underlying mechanism has been described. From the first descriptions of M. africanum in the literature in 1969, the time to a positive culture of M. africanum on solid medium was known to be longer than the time to a positive culture of M. tuberculosis. However, the delayed growth of M. africanum, which may correlate with the less virulent phenotype in the human host, has not previously been studied in detail. METHODOLOGY/PRINCIPAL FINDINGS: We compared the growth rates of M. tuberculosis and M. africanum isolates from The Gambia in two liquid culture systems. M. africanum grows significantly slower than M. tuberculosis, not only when grown directly from sputa, but also in growth experiments under defined laboratory conditions. We also sequenced four M. africanum isolates and compared their whole genomes with the published M. tuberculosis H37Rv genome. M. africanum strains have several non-synonymous SNPs or frameshift mutations in genes that were previously associated with growth-attenuation. M. africanum strains also have a higher mutation frequency in genes crucial for transport of sulphur, ions and lipids/fatty acids across the cell membrane into the bacterial cell. Surprisingly, 5 of 7 operons, recently described as essential for intracellular survival of H37Rv in the host macrophage, showed at least one non-synonymously mutated gene in M. africanum. CONCLUSIONS/SIGNIFICANCE: The altered growth behaviour of M. africanum might indicate a different survival strategy within host cells

Reconstrucción ósea acetabular con cotilos no cementados y aporte de aloinjerto en la artroplastia total de cadera : estudio de 35 casos

Se han revisado 35 arlroplastias realizadas en 29 pacientes portadores de algún tipo de defecto óseo en el cotilo por fallo de prótesis total de cadera. En el presente estudio incluimos sólo las reconstrucciones acetabulares efectuadas con implantes no cementados. La edad media fue de 60 años (29/79), siendo 19 mujeres y 10 varones. Clasificamos los defectos óseos siguiendo a D'Antonio en segmentarios, cavitarios y mixtos, y para la reparación de dichos defectos utilizamos aloinjerto criopreservado en todos los casos excepto uno, tratado con injerto liofilizado. Valoramos los resultados desde un punto de vista clínico, subjetivo y objetivo (escala de Harris). Desde un punto de vista radiológico se analizaron las migraciones del implante acetabular, la existencia de zonas de radiolucencia, las osificaciones periarticulares y la incorporación o no del injerto óseo utilizado. Desde el punto de vista clínico obtuvimos un 60% de resultados excelentes y buenos, frente a un 40% de regulares y malos. Desde cualquier punto de vista el índice de aflojamiento del componente acetabular fue mucho mayor que el que puede obtenerse con cotilos no defectuososThirty five revision hip arthroplasties performed in 29 patients with acetabular bone defects were reviewed. In this series we only include the acetabular reconstruction performed using non cemented acetabular implants. The mean age of the patients was 60 years (29-79), 19 were female and 10 male. We classified the acetabular bone defects according to D'Antonio, in segmentary, cavitary and combined. To repair these defects, we used criopreserved allograft, except one case in which a liofilized allograft was used. The results were evaluated clinically (modified Harris hip score) and radiographically, looking for acetabular migrations, radiolucent lines, periarticular ossifications and bone graft incorporation. We obtained 60% of excellent and good results. There was 40% of poor and fair results. The acetabular loosening rate was higher than in revision hip arthroplasty without acetabular bone defects

Upper Limb Posture Estimation in Robotic and Virtual Reality-based Rehabilitation.

New motor rehabilitation therapies include virtual reality (VR) and robotic technologies. In limb rehabilitation, limb posture is required to (1) provide a limb realistic representation in VR games and (2) assess the patient improvement. When exoskeleton devices are used in the therapy, the measurements of their joint angles cannot be directly used to represent the posture of the patient limb, since the human and exoskeleton kinematic models differ. In response to this shortcoming, we propose a method to estimate the posture of the human limb attached to the exoskeleton. We use the exoskeleton joint angles measurements and the constraints of the exoskeleton on the limb to estimate the human limb joints angles. This paper presents (a) the mathematical formulation and solution to the problem, (b) the implementation of the proposed solution on a commercial exoskeleton system for the upper limb rehabilitation, (c) its integration into a rehabilitation VR game platform, and (d) the quantitative assessment of the method during elbow and wrist analytic training. Results show that this method properly estimates the limb posture to (i) animate avatars that represent the patient in VR games and (ii) obtain kinematic data for the patient assessment during elbow and wrist analytic rehabilitation

Fracturas de las espinas tibiales en el niño y en el adulto

Presentamos una serie de 29 fracturas de las espinas tibiales en 27 pacientes, 11 niños y 16 adultos. Para su estudio hemos seguido la clasificación de Meyers y McKeever, siendo las fracturas tipo II las más frecuentes. Se registraron las lesiones asociadas de la rodilla, y la más frecuente fue la del ligamento lateral interno; encontramos 2 fracturas de Segond en niños. El tratamiento fue conservador en 7 casos y quirúrgico en los 22 restantes. Para evaluar el resultado final estudiamos el desplazamiento de la fractura, movilidad y laxitudes residuales de la rodilla y fuerza muscular. Usamos las escalas de Lysholm y de Tegner para la valoración funcional. Un estudio radiológico con 3 proyecciones se llevó a cabo en todos los pacientes. El tiempo medio de seguimiento fue de 9,7 años para el grupo de niños y de 8,2 para los adultos. Los resultados globales, de acuerdo con la escala de Lysholm, fueron excelentes, pero se registraron 11 laxitudes anteroposteriores y 4 laterales, aunque 11 de estos 15 pacientes permanecen asintomáticos. Muchas de estas laxitudes aparecen en fracturas anatómicamente reducidas. Sugerimos que debe realizarse estudio artroscópico en estos pacientes para detectar lesiones asociadas que empeoran el resultado.A series of 29 fractures of the tibial spine in 27 patients, 11 children and 16 adults. We followed Meyers and McKeever to classify the fractures, tipe II being the most frecuent. Associated injuries of the knee were registered, being medial collateal ligament the most frecuent. We found 2 Segond fractures in young patients. The treatment was conservative in 7 cases and surgical in the remaining 22. To evaluate the final result we studied the displacement of the fracture, mobility of the knee, anteroposterior and lateral inestabilities, muscle strength. We used the Lysholm and the Tegner rating systems to evaluate the functional result. A complete radiological evaluation (three views) was made in all the patients. The average follow-up times was 9.7 years for the children group, and 8.2 years for the adult group. The overall results according to the Lysholm rating scale were excellent, but 11 anteroposterior and 4 lateral laxities were registered, though 11 of the 15 cases remains asymptomatic. Many of theese laxities appeared in anatomically reduced fractures. We suggest that an arthroscopic study of the patients must be done to detect associated injuries that produces a worse final result

Resultados a largo plazo de la patelectomía total

Desde el año 1981 hemos realizado 19 patelectomías totales, 9 por artrosis femoropatelar, 8 por dolor anterior de rodilla y 2 por fracturas conminutas. La edad media en el momento de la intervención era de 48 años (25-80); todos los pacientes con dolor anterior habían sido operados previamente. Con una evolución media de 7,8 años (3-14), hemos realizado una revisión clínica y radiológica. Según la escala de la Sociedad Internacional de Rodilla obtuvimos un 58% de resultados excelentes y buenos, resaltando que continúan con dolor todos los pacientes operados por artrosis y el 50% de los intervenidos por dolor anterior. La patelectomía total es una técnica cada vez menos utilizada, limitándose sus indicaciones a fracturas muy conminutas, artrosis femoropatelar en pacientes en los que estaría contraindicada la artroplastia total y en cuadros de dolor anterior de rodilla rebeldes a otros tratamientosNineteen total patelectomies were performed since 1981. The indication was femoropatellar osteoarthritis in nine cases, anterior knee pain syndrome in eight, and conminute fractures in two. The mean age of the group at the time of operation was 48 years (25-80). A1l the patients with anterior knee pain syndrome had been operated previously. With an average followup time of 7.8 years (3-14), vve reviewed our patients clinically and radiographically. We used the International Knee Society rating scale and found 58% of excellent and good results; 100% of the patients operated because of osteoarthritis and 50% of those operated because an anterior knee pain syndrome have pain at review. Total patellectomy is not a frequent technique. Today, the sole indications are very conminute fractures of the patella, femoropatellar osteoarthritis in those patients in which total knee arthroplasty is not indicated and in the anterior knee pain syndrome not improved with other treatments

Gene expression responses to anti-tuberculous drugs in a whole blood model.

BACKGROUND: There is a need for better tools to evaluate new or repurposed TB drugs. The whole blood bactericidal activity (WBA) assay has been advocated for this purpose. We investigated whether transcriptional responses in the WBA assay resemble TB responses in vivo, and whether the approach might additionally reveal mechanisms of action. RESULTS: 1422 of 1798 (79%) of differentially expressed genes in WBA incubated with the standard combination of rifampicin, isoniazid, pyrazinamide and ethambutol were also expressed in sputum (P < 0.0001) obtained from patients taking the same combination of drugs; these comprised well-established treatment-response genes. Gene expression profiles in WBA incubated with the standard drugs individually, or with moxifloxacin or faropenem (with amoxicillin and clavulanic acid) clustered by individual drug exposure. Distinct pathways were detected for individual drugs, although only with isoniazid did these relate to known mechanisms of drug action. CONCLUSIONS: Substantial agreement between whole blood cultures and sputum and the ability to differentiate individual drugs suggest that transcriptomics may add value to the whole blood assay for evaluating new TB drugs

Methylation in mycobacterium tuberculosis is lineage specific with associated mutations present globally

DNA methylation is an epigenetic modification of the genome involved in regulating crucial cellular processes, including transcription and chromosome stability. Advances in PacBio sequencing technologies can be used to robustly reveal methylation sites. The methylome of the Mycobacterium tuberculosis complex is poorly understood but may be involved in virulence, hypoxic survival and the emergence of drug resistance. In the most extensive study to date, we characterise the methylome across the 4 major lineages of M. tuberculosis and 2 lineages of M. africanum, the leading causes of tuberculosis disease in humans. We reveal lineage-specific methylated motifs and strain-specific mutations that are abundant globally and likely to explain loss of function in the respective methyltransferases. Our work provides a set of sixteen new complete reference genomes for the Mycobacterium tuberculosis complex, including complete lineage 5 genomes. Insights into lineage-specific methylomes will further elucidate underlying biological mechanisms and other important phenotypes of the epi-genom

Genetic regulation of gene expression of MIF family members in lung tissue.

Macrophage migration inhibitory factor (MIF) is a cytokine found to be associated with chronic obstructive pulmonary disease (COPD). However, there is no consensus on how MIF levels differ in COPD compared to control conditions and there are no reports on MIF expression in lung tissue. Here we studied gene expression of members of the MIF family MIF, D-Dopachrome Tautomerase (DDT) and DDT-like (DDTL) in a lung tissue dataset with 1087 subjects and identified single nucleotide polymorphisms (SNPs) regulating their gene expression. We found higher MIF and DDT expression in COPD patients compared to non-COPD subjects and found 71 SNPs significantly influencing gene expression of MIF and DDTL. Furthermore, the platform used to measure MIF (microarray or RNAseq) was found to influence the splice variants detected and subsequently the direction of the SNP effects on MIF expression. Among the SNPs found to regulate MIF expression, the major LD block identified was linked to rs5844572, a SNP previously found to be associated with lower diffusion capacity in COPD. This suggests that MIF may be contributing to the pathogenesis of COPD, as SNPs that influence MIF expression are also associated with symptoms of COPD. Our study shows that MIF levels are affected not only by disease but also by genetic diversity (i.e. SNPs). Since none of our significant eSNPs for MIF or DDTL have been described in GWAS for COPD or lung function, MIF expression in COPD patients is more likely a consequence of disease-related factors rather than a cause of the disease