981 resultados para Open reduction


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We introduced disulfide bonds to lock the integrin αLβ2 I domain in predicted open, ligand binding or closed, nonbinding conformations. Transfectants expressing αLβ2 heterodimers containing locked-open but not locked-closed or wild-type I domains constitutively adhered to intercellular adhesion molecule-1 (ICAM-1) substrates. Locking the I domain closed abolished constitutive and activatable adhesion. The isolated locked-open I domain bound as well as the activated αLβ2 heterodimer, and binding was abolished by reduction of the disulfide. Lovastatin, which binds under the conformationally mobile C-terminal α-helix of the I domain, inhibited binding to ICAM-1 by αLβ2 with wild-type, but not locked-open I domains. These data establish the importance of conformational change in the αL I domain for adhesive function and show that this domain is sufficient for full adhesive activity.

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Regulation of ion channel function by intracellular processes is fundamental for controlling synaptic signaling and integration in the nervous system. Currents mediated by N-methyl-D-aspartate (NMDA) receptors decline during whole-cell recordings and this may be prevented by ATP. We show here that phosphorylation is necessary to maintain NMDA currents and that the decline is not dependent upon Ca2+. A protein tyrosine phosphatase or a peptide inhibitor of protein tyrosine kinase applied intracellularly caused a decrease in NMDA currents even when ATP was included. On the other hand, pretreating the neurons with a membrane-permeant tyrosine kinase inhibitor occluded the decline in NMDA currents when ATP was omitted. In inside-out patches, applying a protein tyrosine phosphatase to the cytoplasmic face of the patch caused a decrease in probability of opening of NMDA channels. Conversely, open probability was increased by a protein tyrosine phosphatase inhibitor. These results indicate that NMDA channel activity is reduced by a protein tyrosine phosphatase associated with the channel complex.

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Apesar da utilização da ventilação mecânica protetora como estratégia para o tratamento da síndrome do desconforto respiratório agudo, ao menos um quarto dos pacientes com essa síndrome ainda apresentam redução na função pulmonar após 6 meses de seguimento. Não se sabe se esta redução está relacionada com a gravidade da síndrome ou associada com a forma de ventilar o paciente. Nosso objetivo neste trabalho foi avaliar a associação entre alterações funcionais e estruturais do pulmão com parâmetros de gravidade clínica e de ventilação mecânica. Foi realizada uma análise secundária dos dados obtidos em estudo randomizado e controlado que incluiu pacientes com síndrome do desconforto respiratório agudo moderada/grave, internados em seis unidades de terapia intensiva em um hospital terciário da cidade de São Paulo. Foram analisados dados de pacientes que tinham ao menos um teste de função pulmonar no seguimento. O teste funcional incluiu a medida da capacidade vital forçada, volumes pulmonares e a capacidade de difusão do monóxido de carbono após 1, 2 e 6 meses de seguimento. Foram considerados variáveis independentes o volume corrente, a pressão de distensão e a pressão positiva ao final da expiração (todos medidos após 24 horas da randomização) e um sistema de classificação de prognóstico (APACHE II), a relação PaO2/FIO2 e a complacência respiratória estática (todos medidos antes da randomização). Também foi realizada tomografia de alta resolução do tórax juntamente com os testes de função pulmonar, e posterior análise quantitativa das imagens. Na avaliação de 6 meses também foi realizado teste de caminhada de 6 minutos e um questionário de qualidade de vida (SF-36). Um total de 21 pacientes realizaram o teste de função pulmonar após 1 mês e 15 pacientes realizaram após 2 e 6 meses de seguimento. A capacidade vital forçada foi relacionada inversamente com a pressão de distensão na avaliação de 1, 2 e 6 meses (p < 0,01). A capacidade de difusão do monóxido de carbono relacionou-se inversamente com a pressão de distensão e com o APACHE II (ambos p < 0,01) na avaliação de 1 e 2 meses. Após 6 meses de seguimento, houve correlação inversa entre a pressão de distensão e a capacidade vital forçada independente do volume corrente, da pressão de platô e da complacência estática respiratória após ajustes (R2 = 0,51, p = 0,02). A pressão de distensão também se relacionou com o volume pulmonar total, a densidade pulmonar media e a porcentagem de volume pulmonar não aerado ou pobremente aerado medidos através da análise quantitativa da tomografia computadorizada de tórax realizada na avaliação de 6 meses. Também foi observada relação entre a qualidade de vida após 6 meses de seguimento e a pressão de distensão considerando o domínio estado geral de saúde. Nós concluímos que mesmo em pacientes ventilados com reduzido volume corrente e pressão de platô limitada, maiores valores de pressão de distensão relacionaram-se com menores valores de função pulmonar no seguimento de longo prazo

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The effect of two zeolites, HUSY, NaY and a mesoporous synthesized Al-MCM-41 material on the smoke composition of ten commercial cigarettes brands has been studied. Cigarettes were prepared by mixing the tobacco with the three powdered materials, and the smoke obtained under the ISO conditions was analyzed. Up to 32 compounds were identified and quantified in the gas fraction and 80 in the total particulate matter (TPM) condensed in the cigarettes filters and in the traps located after the mouth end of the cigarettes. Al-MCM-41 is by far the best additive, providing the highest reductions of the yield for most compounds and brands analyzed. A positive correlation was observed among the TPM and nicotine yields with the reduction obtained in nicotine, CO, and most compounds with the three additives. The amount of ashes in additive free basis increases due to the coke deposited on the solids, especially with Al-MCM-41. Nicotine is reduced with Al-MCM-41 by an average of 34.4% for the brands studied (49.5% for the brand where the major reduction was obtained and 18.5 for the brand behaving the worst). CO is reduced by an average of 18.6% (ranging from 10.3 to 35.2% in the different brands).

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The metacestode (larval) stage of the tapeworm Echinococcus multilocularis causes alveolar echinococcosis (AE), a very severe and in many cases incurable disease. To date, benzimidazoles such as albendazole and mebendazole are the only approved chemotherapeutical treatment options. Benzimidazoles inhibit metacestode proliferation, but do not act parasiticidal. Thus, benzimidazoles have to be taken a lifelong, can cause adverse side effects such as hepatotoxicity, and are ineffective in some patients. We here describe a newly developed screening cascade for the evaluation of the in vitro efficacy of new compounds that includes assessment of parasiticidal activity. The Malaria Box from Medicines for Malaria Venture (MMV), comprised of 400 commercially available chemicals that show in vitro activity against Plasmodium falciparum, was repurposed. Primary screening was carried out at 10 μM by employing the previously described PGI assay, and resulted in the identification of 24 compounds that caused physical damage in metacestodes. Seven out of these 24 drugs were also active at 1 μM. Dose-response assays revealed that only 2 compounds, namely MMV665807 and MMV665794, exhibited an EC50 value below 5 μM. Assessments using human foreskin fibroblasts and Reuber rat hepatoma cells showed that the salicylanilide MMV665807 was less toxic for these two mammalian cell lines than for metacestodes. The parasiticidal activity of MMV665807 was then confirmed using isolated germinal layer cell cultures as well as metacestode vesicles by employing viability assays, and its effect on metacestodes was morphologically evaluated by electron microscopy. However, both oral and intraperitoneal application of MMV665807 to mice experimentally infected with E. multilocularis metacestodes did not result in any reduction of the parasite load.

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This letter describes a new idea of increasing operational bandwidth of a compact planar inverted F antenna (PIFA) by introducing open-end slots in the ground plane under the radiating patch. The slots are not in the way of active modules of a wireless transceiver and thus the proposed antenna size reduction method is attractive from the point of view of practical implementation.

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The etiology of primary open-angle glaucoma (POAG) remains the subject of continuing investigation. Despite the many known risk factors and mechanism of damage, the principal treatment objectives in POAG still consist of reduction of intraocular pressure, which although straightforward in many cases, often leaves the clinician with the question of how far to pursue a sufficiently low pressure to prevent further damage. Other risk factors such as hemodynamic insufficiency due to vascular dysregulation and abnormal blood pressure are often overlooked in the day-to-day practice; their harmful effects for glaucoma are, it seems, more potent at night while the patient sleeps and when clinical investigation is most difficult. Although the status of autonomic nervous system is an important determinant of the systemic hemodynamic parameters, this issue is usually ignored by the clinician in the process of glaucoma diagnosis. Consequently, there is a lack of alternative therapies tailored to address associated systemic risk factors for POAG on a case and chronological basis; this approach could be more effective in preventing the progression and visual loss in selected glaucoma cases. © 2004 Elsevier Inc. All rights reserved.

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Aims: To determine the visual outcome following initiation of brimonidine therapy in glaucoma. Methods: 16 newly diagnosed previously untreated glaucoma patients were randomly assigned to either timalal 0.5% or brimanidine 0.2%. Visual acuity, contrast sensitivity (CS), visual fields, intraocular pressure (IOP), blaad pressure, and heart rate were evaluated at baseline and after 3 months. Results: IOP reduction was similar far both groups (p<0.05). Brimanidine improved CS; in the right eye at 6 and 12 cpd (p = 0.043, p = 0.017); in the left eye at 3 and 12 cpd (p = 0.044, p = 0.046). Timolol reduced CS at 18 cpd in the right eye (p = 0.041). There was no change in any other measured parameters. Conclusion: Glaucoma patients exhibit improved CS an initiation of brimanidine therapy.

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We propose that key concepts from clinical psychotherapy can inform science-based initiatives aimed at building tolerance and community cohesion. Commonalities in social and clinical psychology are identified regarding (1) distorted thinking (intergroup bias and cognitive bias), (2) stress and coping (at intergroup level and intrapersonal level), and (3) anxiety (intergroup anxiety and pathological anxiety). On this basis we introduce a new cognitive-behavioral model of social change. Mental imagery is the conceptual point of synthesis, and anxiety is at the core, through which new treatment-based approaches to reducing prejudice can be developed. More generally, we argue that this integration is illustrative of broader potential for cross-disciplinary integration in the social and clinical sciences, and has the potential to open up new possibilities and opportunities for both disciplines.

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This study explored the relationship between social fund projects and poverty reduction in selected communities in Jamaica. The Caribbean nation's social fund projects aim to reduce “public” poverty by rehabilitating and expanding social and economic infrastructure, improving social services, and strengthening organizations at the community level. Research questions addressed the characteristics of poverty-focused social fund projects; the nexus between poverty reduction and three key concepts suggested by the literature— community (citizen) participation, social capital, and empowerment; and the impact of the projects on poverty. ^ In this qualitative study, data were collected and triangulated by means of in-depth, semi-structured interviews, supplemented by key informant data; non-participant observation; and document reviews. Thirty-four respondents were interviewed individually at eight rural and urban sites over a period of four consecutive months, and 10 key informants provided supplementary data. Open, axial, and selective coding was used for data reduction and analysis as part of the grounded theory method, which included constant comparative analysis. The codes generated a set of themes and a substantive-formal theory. Findings were crosschecked with interview respondents and key informants and validated by means of an audit trail. ^ The results have revealed that the approach to poverty reduction in social fund-supported communities is a process of development-focused collaboration among various stakeholders. The process encompasses four stages: (1) identifying problems and priorities, (2) motivating and mobilizing, (3) working together, and (4) creating an enabling environment. The underlying stakeholder involvement theory posits that collaboration increases the productivity of resources and creates the conditions for community-driven development. In addition, the study has found that social fund projects are largely community-based, collaborative, and highly participatory in their implementation, as well as prescription-driven, results-oriented, and leadership-dependent. Further, social capital formation across communities was found to be limited, and in general, the projects have been enabling rather than empowering. The projects have not reduced poverty per se; however, they have been instrumental in improving conditions that were concomitants of poverty. ^

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Purpose – The purpose of this paper is to provide an analysis of sistematización’s use as a research tool in the operationalization of a “neighborhood approach” to the implementation of disaster risk reduction (DRR) in informal urban settlements. Design/methodology/approach – The first section highlights sistematización’s historical origins in Latin America in the fields of popular adult education, social work, and rural development. The second explains why sistematización was made a required component of project implementation. The third section addresses the approach to sistematización used. The final discusses how this experience both contributes to sistematización’s theoretical development and practical application as a methodology. Findings – The introduction of “sistematización” as a research tool facilitated real-time assessment of project implementation, providing timely information that positively influenced decision-making processes. This on-going feedback, collective learning, and open-exchange of know-how between NGOs and partner institutions allowed for the evaluation of existing practices and development of new ways of collaborating to address disaster risk in complex and dynamic urban environments. Practical implications – Sistematización transcends the narrow focus of traditional monitoring and evaluation on final results, emphasizing a comprehensive understanding of processes and contexts. Originality/value – Its use in the implementation of DRR initiatives in informal urban environments is particularly novel, highlighting the capacity of the methodology to be tailored to a variety of needs, in this case, bridging the gap between NGOs, local governments, and vulnerable communities, as well as between urban, development, and disaster risk management planning.

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Background and aims: Machine learning techniques for the text mining of cancer-related clinical documents have not been sufficiently explored. Here some techniques are presented for the pre-processing of free-text breast cancer pathology reports, with the aim of facilitating the extraction of information relevant to cancer staging.

Materials and methods: The first technique was implemented using the freely available software RapidMiner to classify the reports according to their general layout: ‘semi-structured’ and ‘unstructured’. The second technique was developed using the open source language engineering framework GATE and aimed at the prediction of chunks of the report text containing information pertaining to the cancer morphology, the tumour size, its hormone receptor status and the number of positive nodes. The classifiers were trained and tested respectively on sets of 635 and 163 manually classified or annotated reports, from the Northern Ireland Cancer Registry.

Results: The best result of 99.4% accuracy – which included only one semi-structured report predicted as unstructured – was produced by the layout classifier with the k nearest algorithm, using the binary term occurrence word vector type with stopword filter and pruning. For chunk recognition, the best results were found using the PAUM algorithm with the same parameters for all cases, except for the prediction of chunks containing cancer morphology. For semi-structured reports the performance ranged from 0.97 to 0.94 and from 0.92 to 0.83 in precision and recall, while for unstructured reports performance ranged from 0.91 to 0.64 and from 0.68 to 0.41 in precision and recall. Poor results were found when the classifier was trained on semi-structured reports but tested on unstructured.

Conclusions: These results show that it is possible and beneficial to predict the layout of reports and that the accuracy of prediction of which segments of a report may contain certain information is sensitive to the report layout and the type of information sought.

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BACKGROUND: Hemicrania continua is a strictly unilateral, continuous headache, typically mild to moderate in severity, with severe exacerbations commonly accompanied by cranial autonomic features and migrainous symptoms. It is exquisitely responsive to Indomethacin. However, some patients cannot tolerate treatment, often due to gastrointestinal side effects. Therapeutic alternatives are limited and controlled evidence lacking. METHODS: We present our experience of nine patients treated with OnabotulinumtoxinA for hemicrania continua. All patients were injected using the PREEMPT (Phase 3 REsearch Evaluating Migraine Prophylaxis Therapy) protocol for migraine. RESULTS: Five of nine patients demonstrated a 50% or more reduction in moderate to severe headache days with OnabotulinumtoxinA with a median reduction in moderate to severe headache days of 80%. Patient estimate of response was 80% or more in five subjects. The median and mean duration of response in the five responders was 11 and 12 weeks (range 6-20 weeks). Improvements were also seen in headache-associated disability CONCLUSIONS: OnabotulinumtoxinA adds a potential option to the limited therapeutic alternatives available in hemicrania continua.

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This randomized controlled trial was performed to investigate whether placebo effects in chronic low back pain could be harnessed ethically by adding open-label placebo (OLP) treatment to treatment as usual (TAU) for 3 weeks. Pain severity was assessed on three 0- to 10-point Numeric Rating Scales, scoring maximum pain, minimum pain, and usual pain, and a composite, primary outcome, total pain score. Our other primary outcome was back-related dysfunction, assessed on the Roland-Morris Disability Questionnaire. In an exploratory follow-up, participants on TAU received placebo pills for 3 additional weeks. We randomized 97 adults reporting persistent low back pain for more than 3 months' duration and diagnosed by a board-certified pain specialist. Eighty-three adults completed the trial. Compared to TAU, OLP elicited greater pain reduction on each of the three 0- to 10-point Numeric Rating Scales and on the 0- to 10-point composite pain scale (P < 0.001), with moderate to large effect sizes. Pain reduction on the composite Numeric Rating Scales was 1.5 (95% confidence interval: 1.0-2.0) in the OLP group and 0.2 (-0.3 to 0.8) in the TAU group. Open-label placebo treatment also reduced disability compared to TAU (P < 0.001), with a large effect size. Improvement in disability scores was 2.9 (1.7-4.0) in the OLP group and 0.0 (-1.1 to 1.2) in the TAU group. After being switched to OLP, the TAU group showed significant reductions in both pain (1.5, 0.8-2.3) and disability (3.4, 2.2-4.5). Our findings suggest that OLP pills presented in a positive context may be helpful in chronic low back pain.