177 research outputs found
Antiretroviral (ARV) Therapy in Resource Poor Countries: What do we Need in Real Life?
Significant progresses have been made in the last 5 years towards the ultimate goal to provide universal access to care for all HIV/AIDS patients needing antiretroviral treatment in resource-poor countries. However, many barriers are still to be overcome, including (●) cost of care for the individual, (●) stigma, (●) lack of qualified human resources and infrastructure, especially in the rural setting, (●) rescue drugs for failing patients and (●) pediatric formulations. Priority actions to be promoted if the fight against HIV/AIDS is to be successful include: (i) promoting access to care in the rural areas, (ii) strengthening of basic health infrastructures, (iii) waiving of users’ fee to get ARV, (iv) a larger variety of drugs, with particular regard to fixed dose combination third line drugs and pediatric formulations, (v) local quality training and (vi) high quality basic and translational research. While the universal access to HIV care is crucial in developing countries, a strong emphasis on prevention should be maintained along
Molecular detection of rifampin and isoniazid resistance to guide chronic TB patient management in Burkina Faso
<p>Abstract</p> <p>Background</p> <p>Drug-resistant tuberculosis (DR-TB) is considered a real threat to the achievement of TB control. Testing of mycobacterial culture and testing of drug susceptibility (DST) capacity are limited in resource-poor countries, therefore inadequate treatment may occur, favouring resistance development. We evaluated the molecular assay GenoType<sup>® </sup>MTBDR<it>plus </it>(Hain Lifescience, Germany) in order to detect DR-TB directly in clinical specimens as a means of providing a more accurate management of chronic TB patients in Burkina Faso, a country with a high TB-HIV co-infection prevalence.</p> <p>Methods</p> <p>Samples were collected in Burkina Faso where culture and DST are not currently available, and where chronic cases are therefore classified and treated based on clinical evaluation and sputum-smear microscopy results. One hundred and eight chronic TB patients (sputum smear-positive, after completing a re-treatment regimen for pulmonary TB under directly observed therapy) were enrolled in the study from December 2006 to October 2008. Two early morning sputum samples were collected from each patient, immediately frozen, and shipped to Italy in dry ice. Samples were decontaminated, processed for smear microscopy and DNA extraction. Culture was attempted on MGIT960 (Becton Dickinson, Cockeysville, USA) and decontaminated specimens were analyzed for the presence of mutations conferring resistance to rifampin and isoniazid by the molecular assay GenoType<sup>® </sup>MTBDR<it>plus</it>.</p> <p>Results</p> <p>We obtained a valid molecular test result in 60/61 smear-positive and 47/47 smear-negative patients.</p> <p>Among 108 chronic TB cases we identified patients who (i) harboured rifampin- and isoniazid-susceptible strains (n 24), (ii) were negative for MTB complex DNA (n 24), and (iii) had non-tuberculous mycobacteria infections (n 13). The most represented mutation conferring rifampin-resistance was the D516V substitution in the hotspot region of the <it>rpoB </it>gene (43.8% of cases). Other mutations recognized were the H526D (15.6%), the H526Y (15.6%), and the S531L (9.4%).</p> <p>All isoniazid-resistant cases (n 36) identified by the molecular assay were carrying a S315T substitution in the <it>katG </it>gene. In 41.7% of cases, a mutation affecting the promoter region of the <it>inhA </it>gene was also detected.</p> <p>Conclusion</p> <p>The GenoType<sup>® </sup>MTBDR<it>plus </it>assay performed directly on sputum specimens improves the management of chronic TB cases allowing more appropriate anti-TB regimens.</p
Stabilization of mixed finite elements for convection-diffusion problems
none2R. Sacco; F. SaleriSacco, Riccardo; Saleri, FAUSTO EMILI
Scientific computing with MATLAB
This textbook is an introduction to Scientific Computing, in which several numerical methods for the computer solution of certain classes of mathematical problems are illustrated. The authors show how to compute the zeros or the integrals of continuous functions, solve linear systems, approximate functions by polynomials and construct accurate approximations for the solution of differential equations. To make the presentation concrete and appealing, the programming environment Matlab is adopted as a faithful companion. All the algorithms introduced throughout the book are shown, thus furnishing an immediate quantitative assessment of their theoretical properties such as stability, accuracy and complexity. The book also contains the solution to several problems raised through exercises and examples, often originating from specific applications. A specific section is devoted to subjects which were not addressed in the book and indicate the bibliographical references for a more comprehensive treatment of the material
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