Luciano Vieira de Araújo

Trends in antiretroviral drug resistance and clade distributions among HIV-1--infected blood donors in Sao Paulo, Brazil.

Background: We analyzed rates of drug resistance mutations in antiretroviral-naive São Paulo blood donors with recently acquired or established HIV-1 infections and characterized clade diversity in this population. Methods: Six hundred forty-eight seropositive blood donor specimens were identified at the Blood Center of São Paulo between July 1998 and March 2002. To discriminate recent infections, samples were subjected to the standardized testing algorithm for recent HIV seroconversion (less-sensitive enzyme immunoassay) testing algorithm. There were 531 samples with a sufficient volume of serum to attempt polymerase chain reaction (PCR) and viral sequencing; 341 (64%) samples yielded a PCR product that could be sequenced for the reverse transcriptase and protease genes. Mutations were analyzed using the 2005 International AIDS Society mutation list. Results: Of 341 specimens successfully analyzed, 21 (6.3%; 95% confidence interval [CI]: 3.9% to 9.3%) had drug-resistant mutations. The proportion of resistant strains was 12.7% (95% CI: 5.2% to 24.5%) among recently infected individuals compared with 5.0% (95% CI: 2.8% to 8.2%) among those with long-standing infections (P = 0.03). No change in the proportion of drug-resistant strains was observed among recently infected donor samples from the first half of the study period (4 of 32 samples) as compared with the second half (3 of 23 samples; P = 0.95). Of the 341 samples, 277 (81.2%) were classified as subtype B, 25 (7.3%) as subtype F1, 13 (3.8%) as subtype C, and 26 (7.6%) as recombinant strains. The distribution of HIV-1 subtypes was similar among recent and long-standing infected individuals and over time. Conclusions: The prevalence of drug-resistant mutations among newly diagnosed persons in São Paulo city is low and similar to what has been described in Europe and the United States. Although HIV-1 subtype B remains predominant, subtypes F and C and recombinant forms are present in substantial proportions in infected donors.

HBV carrying drug-resistance mutations in chronically infected treatment-naive patients.

BACKGROUND Nucleoside/nucleotide analogue (NA) treatment causes selection pressure for HBV strains carrying mutations conferring NA resistance. Drug-resistance mutations occur in the reverse transcriptase (RT) region of the HBV polymerase gene and spontaneously arise during viral replication. These mutations can also alter the hepatitis B surface (HBs) protein and in some cases reduce binding to HBs antibodies. The spread of NA-resistant HBV may impact the efficacy of antiviral treatment and hepatitis B immunization programmes. In this study, we used direct sequencing to assess the occurrence of HBV carrying known mutations that confer NA resistance in the largest cohort of treatment-naive patients with chronic hepatitis B (CHB) to date. METHODS HBV DNA samples isolated from 702 patients were sequenced and the RT region subjected to mutational analysis. RESULTS There was high genetic variability among the HBV samples analysed: A1 (63.7%), D3 (14.5%), A2 (3.3%), A3 (0.1%), B1 (0.1%), B2 (0.1%), C2 (0.9%), D1 (0.9%), D2 (4.6%), D4 (5.1%), D unclassified subgenotype (0.7%), E (0.6%), F2a (4.6%), F4 (0.4%) and G (0.4%). HBV strains harbouring mutations conferring NA resistance alone or combined with compensatory mutations were identified in 1.6% (11/702) of the patients. CONCLUSIONS HBV strains harbouring resistance mutations can comprise the major population of HBV quasispecies in treatment-naive patients. In Brazil, there is a very low frequency of untreated patients who are infected with these strains. These findings suggest that the spread and natural selection of drug-resistant HBV is an uncommon event and/or most of these strains remain unstable in the absence of NA selective pressure.

The Virological and Immunological Characteristics of the HIV-1-Infected Population in Brazil: From Initial Diagnosis to Impact of Antiretroviral Use.

Background Immunological and virological status of HIV-infected individuals entering the Brazilian public system over time was analyzed. We evaluated the impact of ART on virological, immunological and antiretroviral resistance over time. Methods CD4+ T cell counts, viral loads and genotypes from patients over 13 years old from 2001–2011 were analyzed according to demographic data. We compared groups using parametric t-tests and linear regression analysis in the R statistical software language. Results Mean baseline CD4+ T cell counts varied from 348 (2003) to 389 (2009) and was higher among women (p = 1.1 x 10−8), lower in older patients (p< 1 x 10−8) and lower in less developed regions (p = 1.864 x 10−5). Percentage of treated patients with undetectable viral loads increased linearly from 46% (2001) to 77% (2011), was lower among women (p = 2.851 x 10−6), younger ages (p = 1 x 10−3), and in less developed regions (p = 1.782 x 10−4). NRTI acquired resistance was 86% in 2001–3 and decreased over time. NNRTI resistance increased from 2001-3(50%) to 2006–9 (60%), PI resistance decreased from 2001–3 (60%) to 2009 (40%), and 3-class resistance was stable over time around 25%. Subtype prevalence comprised B (75.3%), B/F recombinants (12.2%), C (5.7%), F (5.3%) and B/C recombinants (1.5%), with regional variations. Three-class resistance was 26.5% among Bs, 22.4% among Fs and 17.2% among Cs. Conclusions HIV diagnosis occurs late, especially among elderly Brazilians. Younger individuals need special attention due to poor virological response to treatment. Antiretroviral Resistance profile is subtype related.

Approaches that use software to support the prevention of pressure ulcer: A systematic review.

CONTEXT The incidence and costs for pressure ulcer (PU) treatment remain high even though preventive methods are applied. Approaches that use software to support the prevention of PU are presented in the literature to make it more effective. OBJECTIVES Identify the state of art of the approaches that use software to support the prevention of PUs. METHODS A systematic literature review was performed to analyze approaches that use software to support the prevention of PU. ACM, IEEE, PubMed, Scopus, CINAHL and Embase databases have been searched with a predetermined search string to identify primary studies. We selected the ones that met the established inclusion criteria. RESULTS Thirty-six articles met the inclusion criteria. To support prevention, most approaches monitor the patient to provide information about exposure to pressure, temperature level, humidity level and estimated body position in bed providing risk factor intensity charts and intensity maps. The main method to perform patients monitoring is using sensors installed on the mattress, but recently, alternative methods have been proposed such as electronic sensors and tactile sensory coils. Part of the approaches performs automated management of the risk factors using ventilation tubes and mattresses with porous cells to decrease bodys temperature and movable cells to automatically redistribute the pressure over the body. Matters as cost of the approach, patient comfort and hygiene of the monitoring equipment is only briefly discussed in the selected articles. No experiments have been conducted to evidence the approached may reduce PU incidence. DISCUSSION AND CONCLUSION Currently, approaches that use software to support the prevention of PU provide relevant information to health professionals such as risk factor intensity charts and intensity maps. Some of them can even automatically manage risk factors in a limited way. Yet, the approaches are based on risk factor monitoring methods that require patients contact with the monitoring equipment. Therefore, some matters need to be considered such as patients comfort and the hygiene or replacement of the equipment due to the risk of infection. With the emergence of new alternative methods of monitoring, new technologies that do not require contact could be explored by new researches. Randomized Control Trials could also be conducted to verify which approaches are really effective to reduce PU incidence.

HIV drug resistance analysis tool based on process algebra

The increasing number of drugs used in HIV patient treatment and the mutations associated with drug resistance make the inference of drug resistance a complex task that demands computational systems. Furthermore, the software development/update can generate an extra level of complexity in the process drug resistance analysis. An alternative to handle the complexity of drug resistance and software development is to use a formal representation of involved processes, such as process algebra. This allows mathematical reasoning about the analysis process, a precise description of system behavior, more advanced computational approaches, as concurrent/parallel execution and (semi) automatic software development. The first contribution of this research is a mapping of drug resistance algorithms rules into expressions of process algebra which facilitates the computational manipulation of theses rules. The second contribution is the HIVdag (HIV Drug Analysis Generator) system. This software supports the definition, generation and analyses of genotypic drug resistance tests based on process algebra expressions. Therefore, the users can easily create/update their own drug resistance algorithms any time and independent of software development.

Use of Medical Subject Headings (MeSH) in Portuguese for categorizing web-based healthcare content

INTRODUCTION Internet users are increasingly using the worldwide web to search for information relating to their health. This situation makes it necessary to create specialized tools capable of supporting users in their searches. OBJECTIVE To apply and compare strategies that were developed to investigate the use of the Portuguese version of Medical Subject Headings (MeSH) for constructing an automated classifier for Brazilian Portuguese-language web-based content within or outside of the field of healthcare, focusing on the lay public. METHODS 3658 Brazilian web pages were used to train the classifier and 606 Brazilian web pages were used to validate it. The strategies proposed were constructed using content-based vector methods for text classification, such that Naive Bayes was used for the task of classifying vector patterns with characteristics obtained through the proposed strategies. RESULTS A strategy named InDeCS was developed specifically to adapt MeSH for the problem that was put forward. This approach achieved better accuracy for this pattern classification task (0.94 sensitivity, specificity and area under the ROC curve). CONCLUSIONS Because of the significant results achieved by InDeCS, this tool has been successfully applied to the Brazilian healthcare search portal known as Busca Saúde. Furthermore, it could be shown that MeSH presents important results when used for the task of classifying web-based content focusing on the lay public. It was also possible to show from this study that MeSH was able to map out mutable non-deterministic characteristics of the web.

A rigorous approach to facilitate and guarantee the correctness of the genetic testing management in human genome information systems

BackgroundRecent medical and biological technology advances have stimulated the development of new testing systems that have been providing huge, varied amounts of molecular and clinical data. Growing data volumes pose significant challenges for information processing systems in research centers. Additionally, the routines of genomics laboratory are typically characterized by high parallelism in testing and constant procedure changes.ResultsThis paper describes a formal approach to address this challenge through the implementation of a genetic testing management system applied to human genome laboratory. We introduced the Human Genome Research Center Information System (CEGH) in Brazil, a system that is able to support constant changes in human genome testing and can provide patients updated results based on the most recent and validated genetic knowledge. Our approach uses a common repository for process planning to ensure reusability, specification, instantiation, monitoring, and execution of processes, which are defined using a relational database and rigorous control flow specifications based on process algebra (ACP). The main difference between our approach and related works is that we were able to join two important aspects: 1) process scalability achieved through relational database implementation, and 2) correctness of processes using process algebra. Furthermore, the software allows end users to define genetic testing without requiring any knowledge about business process notation or process algebra.ConclusionsThis paper presents the CEGH information system that is a Laboratory Information Management System (LIMS) based on a formal framework to support genetic testing management for Mendelian disorder studies. We have proved the feasibility and showed usability benefits of a rigorous approach that is able to specify, validate, and perform genetic testing using easy end user interfaces.

A Health Mobile Application and Architecture to Support and Automate In-home Consultation

Home care services are becoming increasingly important as a strategy to offer customized treatment to fragile patients. The continuity of medical care is essential to the services quality, and devices to help with it are welcome. In this context, mHealth apps -- or mobile health applications -- can be used to manage tasks related to home consultations and to follow up health care, using software resources to improve the treatment results. This paper presents a health mobile application developed to this end, providing an architecture to support the integration and automation of long-term tasks carried out through different phases of the treatment, in order to help physicians before, during, and after home visits. It also supports treatment adherence, offering follow-up alerts and data to set up remainder medical applications. Moreover, this approach aims to increase the quality of health care, helping to reduce errors related to misunderstanding of medical prescriptions or misconfigurations of medication reminder apps.

MoVEROffice: Virtual Reality for Upper Limbs Rehabilitation

Considering the complexity involved in the motor rehabilitation process, this paper presents the development of a serious game with virtual reality and natural interaction to act as a support tool for physical therapy professionals. The objective of the developed application is to enable that patients acquire skill in performing tasks in the virtual environment to transfer them later to the real environment. An experiment was conducted to compare the performance of people with and without mobility limitations in the use of the virtual environment. The results showed that the time spent for performing tasks tend to be reduced when the users familiarize them selves with natural interaction, and size and position of objects have influence in the interaction. The study allowed inferring in this sample evaluated that the motor limitations of the patients did not have influence in the performance of the volunteers.

Virtual Walking Stick: Mobile Application to Assist Visually Impaired People to Walking Safely

People affected by temporary visual limitations or early permanent limitations have the challenge of adapting the way to perform their daily tasks. In particular, the activity of walking without support of others not only requires extensive adaptation but also can expose individuals to the risk. For instance, if an object is not identified during the walk, serious accidents may happen. Therefore, assist blind people to walk independently and safely is an important challenge for computational area. With the popularity of smartphones, cameras and new sensors are available at affordable prices and can be used to develop software to help visually impaired people to walk more independently and safely. This paper presents the development of a mobile application to help visually impaired people to walk independently, using the smartphones camera to alert them about obstacles on the way.