Brugada syndrome with monomorphic ventricular tachycardia in a one-year-old child.

A one-year-old child with a structurally normal heart presented with monomorphic ventricular tachycardia. Electrocardiogram in sinus rhythm showed right bundle branch block with ST segment elevation suggesting a diagnosis of Brugada syndrome. At a later date, when the ST segment was isoelectric. intravenous procainamide caused ST elevation typical of Brugada syndrome.     

Mathematical modeling of polymer erosion: consequences for drug delivery

Bioerodible polymers have been extensively used as carriers for drug delivery and as scaffolds for tissue engineering. The ability to model and predict erosion behavior can enable the rational design and optimization of biomaterials for various biomedical applications in vivo. This review examines critically the current approaches in mathematical modeling of the erosion of synthetic polymers. The models are classified broadly based on whether they use phenomenological, probabilistic, or empirical approaches. An analysis of the various physical, chemical, and biological factors affecting polymer erosion and the classes of bioerodible polymers to which these analyses have been applied are discussed. The key features and assumptions associated with each of the models are described, and information is provided on the limitations of the models and the various approaches. The review concludes with several directions for future models of polymer erosion.     

Therapeutic effect of <Emphasis Type="Italic">Saraca asoca</Emphasis> (Roxb.) Wilde on lysosomal enzymes and collagen metabolism in adjuvant induced arthritis

Rheumatoid arthritis is a chronic, progressive and systemic inflammatory disorder mainly affecting the synovial joints. In the present study, we evaluated the anti-arthritic effect of the methanol extract of Saraca asoca (Roxb.) Wilde., (Fabaceae) on adjuvant induced arthritis by assessing paw swelling, body weight, the levels of lysosomal enzymes, protein bound carbohydrates, serum cytokines, urinary collagen and histopathology of joints. It was found that S. asoca methanol extract at doses of 50, 100 and 200 mg/kg reduced the paw thickness and elevated the mean body weight of arthritic rats. The treatment of S. asoca showed a significant reduction in the levels of both plasma and liver lysosomal enzymes. The protein bound carbohydrates and urinary collagen contents were also decreased at a significant level by the treatment of S. asoca methanol extract. The histopathological study of the joints showed the anti-arthritic property of S. asoca which nearly normalized the histological architecture of the joints. Further, we established the anti-arthritic activity of S. asoca methanol extract by measuring the levels of cytokines in both arthritic and treated rats. The treatment of S. asoca reduced the levels of pro-inflammatory cytokines. In conclusion, S. asoca methanol extract was capable of ameliorating the conditions of arthritis in adjuvant induced arthritic rats.     

A review on biological activities and chemical synthesis of hydrazide derivatives

There has been considerable interest in the development of novel compounds with anticonvulsant, antioxidant, hormone antagonist, analgesic, anti-inflammatory, antiplatelet, antimalarial, antimicrobial, antimycobacterial, antitumoral, vasodilator, antiviral and anti-trypanosomal activities. Hydrazones possessing an azometine -NHN=CH- proton constitute an important class of compounds for new drug development. Therefore, many researchers have synthesized these compounds as target structures and evaluated their biological activities. These observations have been guiding for the development of new hydrazide derivatives that possess varied biological activities.     

Regulation of immune responses to HPV infection and during HPV-directed immunotherapy

Generating an immune response tailored to destroy an infecting organism while limiting bystander damage involves guiding T-cell activation using a variety of cues taken from the immunogen (antigen type, dose, and persistence, accompanying danger signals) as well as the host (tissue environment, T-cell frequency, and affinity for antigen). Dendritic cells (DCs) serve as translators of much of this information and are critically required for effective pathogen and tumor clearance. Moreover, dysregulation of DC activation can lead to autoimmunity. Inhibition of the lymphotoxin (LT) and CD40 pathways has been shown to be effective at quieting inflammation in settings where DC-T-cell interactions are key instigators of disease progression. In this review, we compare and contrast the CD40 and LT pathways in the context of receptor/ligand expression, signal transduction, and DC biology. We provide evidence that these two pathways play complementary roles in DC cytokine secretion, thus indirectly shaping the nature of the CD8(+) T-cell response to foreign antigen. Given the distinct role of these pathways in the context of DC function, we propose that dual therapies targeted at both the CD40 and LTβ receptor may have therapeutic potential in silencing DC-driven autoimmunity or in promoting tumor clearance.     

Toward a new methodological paradigm for testing theories of health behavior and health behavior change

Objective

Traditional theory testing commonly applies cross-sectional (and occasionally longitudinal) survey research to test health behavior theory. Since such correlational research cannot demonstrate causality, a number of researchers have called for the increased use of experimental methods for theory testing.

Methods

We introduce the multi-methodological theory-testing (MMTT) framework for testing health behavior theory.

Results

The MMTT framework introduces a set of principles that broaden the perspective of how we view evidence for health behavior theory. It suggests that while correlational survey research designs represent one method of testing theory, the weaknesses of this approach demand that complementary approaches be applied. Such approaches include randomized lab and field experiments, mediation analysis of theory-based interventions, and meta-analysis.

Conclusion

These alternative approaches to theory testing can demonstrate causality in a much more robust way than is possible with correlational survey research methods. Such approaches should thus be increasingly applied in order to more completely and rigorously test health behavior theory.

Practice implications

Greater application of research derived from the MMTT may lead researchers to refine and modify theory and ultimately make theory more valuable to practitioners.