DNA restriction fragment length polymorphism analysis of Mycobacterium tuberculosis isolates from HIV-seropositive and HIV-seronegative patients in Kampala, Uganda

<p>Abstract</p> <p>Background</p> <p>The identification and differentiation of strains of <it>Mycobacterium tuberculosis </it>by DNA fingerprinting has provided a better understanding of the epidemiology and tracing the transmission of tuberculosis. We set out to determine if there was a relationship between the risk of belonging to a group of tuberculosis patients with identical mycobacterial DNA fingerprint patterns and the HIV sero-status of the individuals in a high TB incidence peri-urban setting of Kampala, Uganda.</p> <p>Methods</p> <p>One hundred eighty three isolates of <it>Mycobacterium tuberculosis </it>from 80 HIV seropositive and 103 HIV seronegative patients were fingerprinted by standard IS<it>6110</it>-RFLP. Using the BioNumerics software, strains were considered to be clustered if at least one other patient had an isolate with identical RFLP pattern.</p> <p>Results</p> <p>One hundred and eighteen different fingerprint patterns were obtained from the 183 isolates. There were 34 clusters containing 54% (99/183) of the patients (average cluster size of 2.9), and a majority (96.2%) of the strains possessed a high copy number (≥ 5 copies) of the IS<it>6110 </it>element. When strains with <5 bands were excluded from the analysis, 50.3% (92/183) were clustered, and there was no difference in the level of diversity of DNA fingerprints observed in the two sero-groups (adjusted odds ratio [aOR] 0.85, 95%CI 0.46–1.56, <it>P </it>= 0.615), patients aged <40 years (aOR 0.53, 95%CI 0.25–1.12, <it>P </it>= 0.100), and sex (aOR 1.12, 95%CI 0.60–2.06, <it>P </it>= 0.715).</p> <p>Conclusion</p> <p>The sample showed evidence of a high prevalence of recent transmission with a high average cluster size, but infection with an isolate with a fingerprint found to be part of a cluster was not associated with any demographic or clinical characteristics, including HIV status.</p

3D Bioprinted Human Skeletal Muscle Constructs for Muscle Function Restoration

A bioengineered skeletal muscle tissue as an alternative for autologous tissue flaps, which mimics the structural and functional characteristics of the native tissue, is needed for reconstructive surgery. Rapid progress in the cell-based tissue engineering principle has enabled in vitro creation of cellularized muscle-like constructs; however, the current fabrication methods are still limited to build a three-dimensional (3D) muscle construct with a highly viable, organized cellular structure with the potential for a future human trial. Here, we applied 3D bioprinting strategy to fabricate an implantable, bioengineered skeletal muscle tissue composed of human primary muscle progenitor cells (hMPCs). The bioprinted skeletal muscle tissue showed a highly organized multi-layered muscle bundle made by viable, densely packed, and aligned myofiber-like structures. Our in vivo study presented that the bioprinted muscle constructs reached 82% of functional recovery in a rodent model of tibialis anterior (TA) muscle defect at 8 weeks of post-implantation. In addition, histological and immunohistological examinations indicated that the bioprinted muscle constructs were well integrated with host vascular and neural networks. We demonstrated the potential of the use of the 3D bioprinted skeletal muscle with a spatially organized structure that can reconstruct the extensive muscle defects

Aluminium for future generation: new bauxite resources identified in Guinea

International audienceGuinea in West Africa is home to about 27% of the world's bauxite reserves – aluminium's principal ore. The well-known Sangaredi deposit alone represents other 80% of the Guinean bauxite production, with an annual production of about 14 Mt. Numerous potentially interesting plateaus have been inventoried but they were poorly explored and their resources remain poorly constrained. Two large areas have been explored between 2006 and 2009, one (Batafong) located north of Boke, the other one (Lelouma) located to the west of Labé. The most promising plateaus were first identified by combined gamma-ray spectrometry and GIS automated delineation constrain by pertinent topographic parameters. These plateaus were then explored by systematic Auger and core drilling completed by pits. These works led to the identification of around 1 400Mt of high quality gibbsitic bauxite grading more than 45 % Al2O3 and less than 2.6 % SiO2 with good content of available alumina and low content in reactive silica

Experimental evidence for lava-like mud flows under Martian surface conditions

Large outflow channels on ancient terrains of Mars have been interpreted as the products of catastrophic flood events. The rapid burial of water-rich sediments after such flooding could have led to sedimentary volcanism, in which mixtures of sediment and water (mud) erupt to the surface. Tens of thousands of volcano-like landforms populate the northern lowlands and other local sedimentary depocentres on Mars. However, it is difficult to determine whether the edifices are related to igneous or mud extrusions, partly because the behaviour of extruded mud under Martian surface conditions is poorly constrained. Here we investigate the mechanisms of mud propagation on Mars using experiments performed inside a low-pressure chamber at cold temperatures. We found that low viscosity mud under Martian conditions propagates differently from that on Earth, because of a rapid freezing and the formation of an icy crust. Instead, the experimental mud flows propagate like terrestrial pahoehoe lava flows, with liquid mud spilling from ruptures in the frozen crust, and then refreezing to form a new flow lobe. We suggest that mud volcanism can explain the formation of some lava-like flow morphologies on Mars, and that similar processes may apply to cryovolcanic extrusions on icy bodies in the Solar System

Chevrel Phases: Genesis and Developments

International audienceThis chapter summarizes the important role played by Marcel Sergent in the discovery in the Rennes Laboratory of the Chevrel Phases, which stimulated considerable interest in the international solid-state chemistry community, because of their remarkable superconducting properties. After a brief general introduction to this topic, the seminal discoveries associated with these phases between 1970 and 1990 are described. After that their initial synthesis and structural determination was discovered, it was necessary to establish their critical superconducting transition temperature, the critical magnetic field, and the critical current density in wires, single crystals, and thin films. More recently their applications as battery materials, in catalysis, and their thermoelectric properties have been studied and are briefly described. These phases opened up the way not only to a rich solid-state chemistry but also to a rich solution chemistry, which complemented the classical field of transition metal carbonyl clusters. The basic cluster units of the Chevrel Phases continue to be studied in the Rennes Laboratory by the heirs of Marcel Sergent and more widely in the international community

Long-term outcomes of 1326 laparoscopic incisional and ventral hernia repair with the routine suturing concept: a single institution experience

Purpose: This retrospective chart analysis reports and assesses the long-term (beyond 10 years) safety and efficiency of a single institution’s experience in 1326 laparoscopic incisional and ventral hernia repairs (LIVHR), defending the principle of the suturing defect (augmentation repair concept) prior to laparoscopic reinforcement with a composite mesh (IPOM Plus). This study aims to prove the feasibility and validity of IPOM Plus repair, among other concepts, as a well-justified treatment of incisional or ventral hernias, rendering a good long-term outcome result. Methods: A single institution’s systematic retrospective review of 1326 LIVHR was conducted between the years 2000 and 2014. A standardized technique of routine closure of the defect prior to the intraperitoneal onlay mesh (IPOM) reinforcement was performed in all patients. The standardized technique of “defect closure” by laparoscopy approximating the linea alba under physiological tension was assigned by either the transparietal U reverse interrupted stitches or the extracorporeal closure in larger defects. All patients benefited from the implant Parietex composite® mesh through an Intraperitoneal Onlay Mesh placement with transfacial suturing. Results: LIVHR was performed on 1326 patients, 52.57 % female and 47.43 % male. The majority of our patients were young (mean age 52.19 years) and obese (average BMI 32.57 kg/m2). The mean operating time was 70 min and hospital stay 2 days, with a mean follow-up of 78 months. On the overall early complications of 5.78 %, we achieved over time the elimination of the dead space by routine closure of the defect, thus reducing seroma formation to 2.56 %, with a low risk of infection <1 %. Post-op sepsis occurred in only nine cases. Three secondary serosal breakdowns and two late perforations were re-operated, and three diabetic patients had infected hematomas, necessitating mesh removal. Through technical improvement in the suturing concept and our growing experience, we managed to reduce the incidence of transient pain to a low acceptable rate of 3.24 % (VAS 5–7) that decreased to 2.56 % on a chronic pain stage, which is comparable to the literature. On the overall rate of late complications of 10.74 %, we noticed also that by reducing the dead space, the chronic pain, skin bulging, and rate of recurrence were reduced to, respectively, 2.56, 1.50, and 4.72 %. One case of mortality was due to a tracheal stenosis, responsible for an acute respiratory syndrome. On a second-look follow-up of 126 patients (9.5 %), 45.23 % were adhesion free, 42.06 % had minor adhesions classified as Müller I, and 12.69 % had serosal adhesions classified as Müller II. Conclusion: Our long series confirms the unexpected high rate of feasibility in the suturing concept or augmentation technique, and confers additional benefits to the conventional advantages of LIVHR in terms of reducing the overall morbidity, with a low rate of recurrences. Based on our experience and study, the current best indications for a successful LIVHR procedure should be tailored upon the limitations of the defect’s width and proper patient selection, to restore adequately the optimal functionality of the abdominal muscles and provide better functional and cosmetic outcomes.SCOPUS: ar.jinfo:eu-repo/semantics/publishe