110 research outputs found
MOLEC: Anywhere and at Any Time Arrhythmia Classification
The new advances in sensor technology, PDAs and wireless communications favor the development of a new type of monitoring systems that can provide patients with assistance anywhere and at any time. Of particular interest are the monitoring systems designed for people that suffer from heart arrhythmias, due to the increasing number of people with cardiovascular diseases. In this paper, we present MOLEC: a PDA-based system that performs local real-time classification and detects the ECG anomalies in situ. In the actual implementation of MOLEC, the signal is acquired by some ECG sensors (ActiveECG sensors) with a 360Hz frequency. For the preprocessing of the signal the ECGPUWAVE tool and an automata developed by us that identifies the beats are used. We have also developed a beat and rhythm classifiers that determine if there has been an anomalous rhythm, and in that case, an alarm is sent to a hospital via wireless communications. The rhythm detection delay of the MOLEC system is of 6.66 seconds. classifier that can run in real-time into a PDA. In this paper we show first the framework of the system, then in section 3 the process that we followed in order to select a beat and rhythm classifier that provides an accuracy result and in section 4 we show some performance aspects considering PDAs resources. 2. Framework of the MOLEC system In this section we explain the four components that form the global architecture of MOLEC (see figure 1): the ECG sensor, the Monitor Molec, Molec Center and the users of the system (hospital and relative computers). 1
Early imaging and molecular changes with neoadjuvant bevacizumab in stage ii/iii breast cancer
This prospective, phase II study evaluated novel biomarkers as predictors of response to bevacizumab in patients with breast cancer (BC), using serial imaging methods and gene expression analysis. Patients with primary stage II/III BC received bevacizumab 15 mg/kg (cycle 1; C1), then four cycles of neoadjuvant docetaxel doxorubicin, and bevacizumab every 3 weeks (C2–C5). Tumour proliferation and hypoxic status were evaluated using18F-fluoro-3'-deoxy-3'-L-fluorothymidine (FLT)-and18F-fluoromisonidazole (FMISO)-positron emission tomography (PET) at baseline, and during C1 and C5. Pre-and post-bevacizumab vascular changes were evaluated using dynamic contrastenhanced magnetic resonance imaging (DCE-MRI). Molecular biomarkers were assessed using microarray analysis. A total of 70 patients were assessed for treatment efficacy. Significant decreases from baseline in tumour proliferation (FLT-PET), vascularity, and perfusion (DCE-MRI) were observed during C1 (p = 0.001), independent of tumour subtype. Bevacizumab treatment did not affect hypoxic tumour status (FMISO-PET). Significant changes in the expression of 28 genes were observed after C1. Changes in vascular endothelial growth factor receptor (VEGFR)-2p levels were observed in 65 patients, with a > 20% decrease in VEGFR-2p observed in 13/65. Serial imaging techniques. © 2021 by the authors. Licensee MDPI, Basel, Switzerland
Absence of system xc⁻ on immune cells invading the central nervous system alleviates experimental autoimmune encephalitis
Background: Multiple sclerosis (MS) is an autoimmune demyelinating disease that affects the central nervous system (CNS), leading to neurodegeneration and chronic disability. Accumulating evidence points to a key role for neuroinflammation, oxidative stress, and excitotoxicity in this degenerative process. System x(c)- or the cystine/glutamate antiporter could tie these pathological mechanisms together: its activity is enhanced by reactive oxygen species and inflammatory stimuli, and its enhancement might lead to the release of toxic amounts of glutamate, thereby triggering excitotoxicity and neurodegeneration.
Methods: Semi-quantitative Western blotting served to study protein expression of xCT, the specific subunit of system x(c)-, as well as of regulators of xCT transcription, in the normal appearing white matter (NAWM) of MS patients and in the CNS and spleen of mice exposed to experimental autoimmune encephalomyelitis (EAE), an accepted mouse model of MS. We next compared the clinical course of the EAE disease, the extent of demyelination, the infiltration of immune cells and microglial activation in xCT-knockout (xCT(-/-)) mice and irradiated mice reconstituted in xCT(-/-) bone marrow (BM), to their proper wild type (xCT(+/+)) controls.
Results: xCT protein expression levels were upregulated in the NAWM of MS patients and in the brain, spinal cord, and spleen of EAE mice. The pathways involved in this upregulation in NAWM of MS patients remain unresolved. Compared to xCT(+/+) mice, xCT(-/-) mice were equally susceptible to EAE, whereas mice transplanted with xCT(-/-) BM, and as such only exhibiting loss of xCT in their immune cells, were less susceptible to EAE. In none of the above-described conditions, demyelination, microglial activation, or infiltration of immune cells were affected.
Conclusions: Our findings demonstrate enhancement of xCT protein expression in MS pathology and suggest that system x(c)- on immune cells invading the CNS participates to EAE. Since a total loss of system x(c)- had no net beneficial effects, these results have important implications for targeting system x(c)- for treatment of MS
Oligodendrocyte differentiation from adult multipotent stem cells is modulated by glutamate
We used multipotent stem cells (MSCs) derived from the young rat subventricular zone (SVZ) to study the effects of glutamate in oligodendrocyte maturation. Glutamate stimulated oligodendrocyte differentiation from SVZ-derived MSCs through the activation of specific N-methyl--aspartate (NMDA) receptor subunits. The effect of glutamate and NMDA on oligodendrocyte differentiation was evident in both the number of newly generated oligodendrocytes and their morphology. In addition, the levels of NMDAR1 and NMDAR2A protein increased during differentiation, whereas NMDAR2B and NMDAR3 protein levels decreased, suggesting differential expression of NMDA receptor subunits during maturation. Microfluorimetry showed that the activation of NMDA receptors during oligodendrocyte differentiation elevated cytosolic calcium levels and promoted myelination in cocultures with neurons. Moreover, we observed that stimulation of MSCs by NMDA receptors induced the generation of reactive oxygen species (ROS), which were negatively modulated by the NADPH inhibitor apocynin, and that the levels of ROS correlated with the degree of differentiation. Taken together, these findings suggest that ROS generated by NADPH oxidase by the activation of NMDA receptors promotes the maturation of oligodendrocytes and favors myelination
Downregulation of PHEX in multibacillary leprosy patients: observational cross-sectional study
Cross-cultural adaptation of the EMIC Stigma Scale for people with leprosy in Brazil
OBJECTIVE Describe the process of cross-cultural adaptation of the “Explanatory Model Interview Catalog – Stigma Scale” for people affected by leprosy in Brazil. METHODS After being authorized by the author of the scale to use it in the national context, we initiated the five steps process of cross-cultural adaptation: (1) translation, (2) synthesis meeting, (3) back-translation, (4) committee of experts and (5) pre-test. The internal consistency of the scale was evaluated using Cronbach’s alpha coefficient. RESULTS The 15 items of the scale’s original version were translated into Brazilian Portuguese. The adapted scale showed evidence of a good understanding of its content, attested both by experts and members of the target population. Its internal consistency was 0.64. CONCLUSIONS The adapted instrument shows satisfactory internal consistency. It may be useful in future studies that intend to provide broad situational analysis that supports solid public health programs with a focus on effective stigma reduction. In a later study, the construct’s validity, criterion, and reproducibility will be evaluated.OBJETIVO Descrever o processo de adaptação transcultural da “Explanatory Model Interview Catalogue – Stigma Scale” para pessoas afetadas por hanseníase no Brasil. MÉTODOS Após a autorização do autor da escala para seu uso no contexto nacional, deu-se início aos cinco passos do processo de adaptação transcultural: (1) tradução, (2) reunião de síntese, (3) retrotradução, (4) comitê de peritos e (5) pré-teste. A consistência interna da escala foi avaliada utilizando o coeficiente alfa de Cronbach. RESULTADOS Os 15 itens da versão original da escala foram traduzidos para a língua portuguesa do Brasil. A escala adaptada apresentou evidência de boa compreensão de seu conteúdo, atestada tanto por peritos como por membros da população alvo. Sua consistência interna foi de 0,64. CONCLUSÕES O instrumento adaptado apresenta consistência interna satisfatória. Pode ser útil em estudos futuros que intencionem viabilizar ampla análise situacional que sustente programas sólidos de saúde pública com enfoque na efetiva redução de estigma. Em estudo ulterior será avaliada a validade de constructo, critério e reprodutibilidade
Impact of PGL-I Seropositivity on the Protective Effect of BCG Vaccination among Leprosy Contacts: A Cohort Study
Although leprosy has become a neglected disease, it is an important cause of disability, and 250,000 new cases are still diagnosed worldwide every year. The current study was carried out in Brazil, where almost 40,000 new cases of leprosy are diagnosed every year. The study targeted contacts of leprosy patients, who are at the highest risk of contracting the disease. We studied 2,135 contacts who were diagnosed at the Leprosy Outpatient Clinic at the Oswaldo Cruz Foundation in Rio de Janeiro, RJ, Brazil, between 1987 and 2007. The presence of antibodies against a specific Mycobacterium leprae antigen (PGL-I) at the first examination and BCG vaccination status were evaluated. PGL-I-positive contacts had a higher risk of developing leprosy than PGL-I-negative contacts. Among the former, vaccinated contacts were at higher risk than unvaccinated contacts. Our results indicate that contact examination combined with PGL-I testing and BCG vaccination appears to justify the targeting of PGL-I-positive individuals for enhanced surveillance. Furthermore, it is highly recommended that PGL-I-positive contacts and contacts with a high familial bacterial index (i.e., the sum of results from index and co-prevalent cases), regardless of serological response, should be monitored. This group could be considered as a target for chemoprophylaxis
Development and validation of a paediatric long-bone fracture classification. A prospective multicentre study in 13 European paediatric trauma centres
Background: The aim of this study was to develop a child-specific classification system for long bone fractures and to examine its reliability and validity on the basis of a prospective multicentre study. Methods: Using the sequentially developed classification system, three samples of between 30 and 185 paediatric limb fractures from a pool of 2308 fractures documented in two multicenter studies were analysed in a blinded fashion by eight orthopaedic surgeons, on a total of 5 occasions. Intra- and interobserver reliability and accuracy were calculated. Results: The reliability improved with successive simplification of the classification. The final version resulted in an overall interobserver agreement of kappa=0.71 with no significant difference between experienced and less experienced raters. Conclusions: In conclusion, the evaluation of the newly proposed classification system resulted in a reliable and routinely applicable system, for which training in its proper use may further improve the reliability. It can be recommended as a useful tool for clinical practice and offers the option for developing treatment recommendations and outcome predictions in the future
Clinic-epidemiological evaluation of ulcers in patients with leprosy sequelae and the effect of low level laser therapy on wound healing: a randomized clinical trial
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