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Antioxidant activity of Blechnum chilense (Kaulf.) Mett., Curcuma domestica Valeton and Tagetes verticillata Lag. & Rodriguez
Carlos A. HINCAPIé,Zulma MONSALVE,David S. SEIGLER,Julio ALARCóN
Boletín Latinoamericano y del Caribe de Plantas Medicinales y Aromáticas , 2011,

Abstract: Debido al creciente interés mundial en el mejoramiento de la salud humana los antioxidantes provenientes de plantas medicinales y alimenticias se han convertido en compuestos de gran interés. La búsqueda de nuevas fuentes de antioxidantes es importante para el mejor uso de la biodiversidad. El objetivo de este trabajo fue evaluar la actividad antioxidante y el contenido de fenoles totales usando el método de Folin-Ciocalteu y la actividad inhibitoria del radical DPPH de fracciones y extractos de Blechnum chilense (Kaulf.) Mett, Curcuma domestica Valeton y Tagetes verticillata Lag. & Rodr. Las fracciones acuosa-metanólica y EtOAc de B. chilense, seguida del extracto EtOAc de C. domestica, mostraron una cantidad importante de compuestos fenólicos. La prueba con DPPH mostró que la actividad secuestrante más importante, comparada con la del extracto metanólico de Aristotelia chilensis (Molina) Stuntz, fue la del extracto de T. verticillata, seguido de la fracción EtOAc de B. chilense y el extracto EtOAc de C. domestica, con resultados similares a la fracción hexánica de B. chilense y el extracto obtenido con éter de petróleo de C. domestica, superando todas la actividad secuestrante de DPPH del -tocoferol. Los resultados sugieren que todas las plantas estudiadas podrían ser nuevas fuentes de antioxidantes y se está trabajando para la identificación de los compuestos responsables de la actividad.

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Spin momentum transfer in current perpendicular to the plane spin valves
M. Covington,A. Rebei,G. J. Parker,M. A. Seigler
Physics , 2003, DOI: 10.1063/1.1707227

Abstract: We present experimental and numerical micromagnetic data on the effect of spin momentum transfer in current perpendicular to the plane spin valves. Starting from a configuration with orthogonal free and pinned layer magnetizations, the free layer magnetization exhibits abrupt current induced switching that is qualitatively consistent with the spin torque model. When operating the spin valve as a field sensor, spin transfer can produce a change in resistance that mimics an effective magnetic field and induce magnetic instability that requires a larger bias field in order to stabilize the device.

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Coupled-Nonlinear Elastic Structure: An Innovative Parameterization Scheme of the Motion Equations [PDF]
S. A. David
Applied Mathematics (AM) , 2014, DOI: 10.4236/am.2014.521324

Abstract: In this paper, I applied the Euler-Lagrange equations in order to obtain the coupled-nonlinear motion equations for an elastic structure. The model is composed of six coupled and strongly nonlinear ordinary differential equations. The new contribution of this work arises from the fact that a convenient and innovative parameterization of the motion equations for the elastic system was developed with all mathematical nonlinearities taken into account, without the usage of any simplifying linearization procedure, as found in most of the works presented in the literature. The results can be used as a source for conducting experiments and can be useful for a better understanding and control of such nonlinear elastic systems.

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The Human Microbiome and I-Cubed: A Modern Medical Paradigm [PDF]
David S. Younger
World Journal of Neuroscience (WJNS) , 2016, DOI: 10.4236/wjns.2016.64031

Abstract: Background: Over the past decade, there has been recognition of the importance of the human microbiome. Beyond improved microbial cataloguing through high- throughput genetic sequencing, we have learned that human beings are superorganisms integrating the identity, function and immunity of resident bacterial, while prepared throughout own innate and adaptive immune systems, to deal with invading organisms. Hypothesis: In keeping with the dynamic relation of infection, immunity and inflammation contained in I-Cubed, illness arises when protective immunity becomes the source of autoimmunity, conditioned by environmental and genetic factors. Results: This paradigm explains the etiopathogenesis of diverse medical (type 1 diabetes, spondyloarthropathy), neurologic (Lyme neuroborreliosis), and neuropsychiatric disorders (PANDAS, and autism spectrum disorders). Conclusion: Successful treatments employing immune-modulatory therapy may be employed. Public health officials will be called upon to guide the public’s understanding and mitigate the risk of disorders that result from the interplay of the human microbiome and I-Cubed.

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Limbic Encephalitis Associated with Voltage-Gated Potassium Channel-Complex Antibodies: Patient Report and Literature Review [PDF]
David S. Younger
World Journal of Neuroscience (WJNS) , 2017, DOI: 10.4236/wjns.2017.71002

Abstract: Background: The family of disorders associated with antibodies against neuronal surface antigens is a rapidly expanding category of autoimmune neurologic disease. Methods: Clinical and laboratory findings of a patient with voltage-gated Kv1 potassium channel (VGKC)-complex autoantibodies are reported and the literature is reviewed. Results: New-onset faciobrachial dystonic seizures, distal large and painful small fiber peripheral neuropathy, dysautonomia, cognitive and memory disturbances were associated with hypometabolism of the left temporal lobe without evidence of systemic malignancy in whole-body positron emission tomography with 2-deoxy-2-[fluorine-18] fluoro-D-glucose integrated with computed tomography. Brain MRI and cerebrospinal fluid were normal with absent intrathecal VGKC-complex antibodies consistent with extrathecal production. Epidermal nerve fiber studies confirmed small fiber neuropathy in association with abnormal autonomic laboratory testing. Discussion: Neurologic involvement associated with VGKC complex autoimmunity is a precisely delineated disorder involving the central, peripheral, and autonomic nervous system.

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Epidemiology of Childhood Mental Illness: A Review of U.S. Surveillance Data and the Literature [PDF]
David S. Younger
World Journal of Neuroscience (WJNS) , 2017, DOI: 10.4236/wjns.2017.71005

Abstract: Background: Childhood mental illness is a major factor of overall lifespan of children continuing into adulthood. Population based surveys and public health surveillance provide the much needed evidence to understand mental health promotion, prevention, and treatment of mental illness in children in the United States. Objective: To review available current national survey data regarding mental illness in children over the past decade and to review the global implications of childhood mental illness. Results: Altogether, 13% - 20% of children experienced a mental health disorder from 1994 to 2011. The prevalence of depression among children of 3 - 17 years old was 3% and the prevalence of lifetime and past year major depressive episode were 12.8% and 8.1% respectively among adolescents of 12 - 17 years old, with a prevalence of depression in the preceding 2 weeks of 6.7%. 7.1% of children of 12 - 17 years old ever had a diagnosis of depression, 3.5% had current depression and 5.1% had a diagnosis of depression in the past year. Overall, 28.5% of high school students of 14 - 18 years old reported feeling so sad or hopeless every day for two weeks or more in a row that they stopped doing usual activities, higher among girls (35.9%) than boys (21.5%), and greater in Hispanic students (32.6%) than white non-Hispanic (27.2%) or black non-Hispanic students (24.7%). The overall rate of suicide in children in 2010 was 4.5 per 100,000. Conclusions: Mental illness presents serious departures from the expected cognitive, social, and emotional development in children, and an important area for prevention in the U.S. and globally. Mental illness will be managed effectively when there is adequate access to treatment services to reduce its associated morbidity and mortality.

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Vaccination: Epidemiological Review [PDF]
David S. Younger
World Journal of Neuroscience (WJNS) , 2017, DOI: 10.4236/wjns.2017.71006

Abstract: The induction of host protective immunity is an important factor in the immunization against potentially fatal disease and emerging illnesses in the U.S. and global populations especially among immunologically susceptible na?ve hosts. Vaccination programs need to be evaluated as regards their health and economic population benefit among indigenous at risk populations taking into account emerging pathologies defined by the sudden appearance of a pathogen in nature or in a region of the world. Global collaboration is a necessary aspect of vaccine-preventable diseases since even a small number of wild-type cases of eradicated diseases in one region of the world present opportunities for their re-emergence in geographically remote areas. This study is a step in the direction of understanding the epidemiologic aspects of vaccination.

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Autoimmune Encephalitides [PDF]
David S. Younger
World Journal of Neuroscience (WJNS) , 2017, DOI: 10.4236/wjns.2017.73027

Abstract: Autoimmune encephalitis is a potentially severe disorder of the brain of diverse causes with a complex differential diagnosis. Recent advances in the past decade have led to the elucidation of new syndromes and biological markers transforming the approach to diagnosis and management of autoimmune encephalitis. Limbic encephalitis, the commonest form of autoimmune encephalitis, combines common presentations of cognitive, psychiatric, and epileptic disorders and has until recently been considered paraneoplastic or postinfectious in origin. The autoimmune encephalitides are clinically and histopathologically associated with serum and intrathecal antibodies to intracellular and surface neuronal antigens, and constituents of the limbic system neuropil. This has led to a reconsideration of a number of neuropsychiatric and neurocognitive disorders as having shared mechanisms of origin. This chapter reviews their historical background, clinical presentation, laboratory evaluation, histopathology, diagnosis and management.

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Hashimoto’s Thyroiditis and Encephalopathy [PDF]
David S. Younger
World Journal of Neuroscience (WJNS) , 2017, DOI: 10.4236/wjns.2017.73026

Abstract: Although very rare, the literature describes cases of Hashimoto encephalopathy attesting to its occurrence. Affected patients present with seizures, stroke-like episodes, transient focal and global neurological deficits, and a variety of neuropsychiatric disturbance from dementia to hallucinations and psychosis. The encephalopathy evolves with concomitantly elevated anti-thyroid peroxidase antibodies, independent from hormonal thyroid function setting it apart from thyrotoxicosis and myxedema. A new patient reported with Hashimoto’s encephalopathy, in whom neurocognitive impairment and stroke-like onset of hemiparesis and hemiparkinsonism correlated with brain magnetic resonance imaging fused with positron emission tomography.

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