The RacGAP ß2-Chimaerin selectively mediates axonal pruning in the hippocampus.

Axon pruning and synapse elimination promote neural connectivity and synaptic plasticity. Stereotyped pruning of axons that originate in the hippocampal dentate gyrus (DG) and extend along the infrapyramidal tract (IPT) occurs during postnatal murine development by neurite retraction and resembles axon repulsion. The chemorepellent Sema3F is required for IPT axon pruning, dendritic spine remodeling, and repulsion of DG axons. The signaling events that regulate IPT axon pruning are not known. We find that inhibition of the small G protein Rac1 by the Rac GTPase-activating protein (GAP) ß2-Chimaerin (ß2Chn) mediates Sema3F-dependent pruning. The Sema3F receptor neuropilin-2 selectively binds ß2Chn, and ligand engagement activates this GAP to ultimately restrain Rac1-dependent effects on cytoskeletal reorganization. ß2Chn is necessary for axon pruning both in vitro and in vivo, but it is dispensable for axon repulsion and spine remodeling. Therefore, a Npn2/ß2Chn/Rac1 signaling axis distinguishes DG axon pruning from the effects of Sema3F on repulsion and dendritic spine remodeling.

Sialylation regulates brain structure and function.

Every cell expresses a molecularly diverse surface glycan coat (glycocalyx) comprising its interface with its cellular environment. In vertebrates, the terminal sugars of the glycocalyx are often sialic acids, 9-carbon backbone anionic sugars implicated in intermolecular and intercellular interactions. The vertebrate brain is particularly enriched in sialic acid-containing glycolipids termed gangliosides. Human congenital disorders of ganglioside biosynthesis result in paraplegia, epilepsy, and intellectual disability. To better understand sialoglycan functions in the nervous system, we studied brain anatomy, histology, biochemistry, and behavior in mice with engineered mutations in St3gal2 and St3gal3, sialyltransferase genes responsible for terminal sialylation of gangliosides and some glycoproteins. St3gal2/3 double-null mice displayed dysmyelination marked by a 40% reduction in major myelin proteins, 30% fewer myelinated axons, a 33% decrease in myelin thickness, and molecular disruptions at nodes of Ranvier. In part, these changes may be due to dysregulation of ganglioside-mediated oligodendroglial precursor cell proliferation. Neuronal markers were also reduced up to 40%, and hippocampal neurons had smaller dendritic arbors. Young adult St3gal2/3 double-null mice displayed impaired motor coordination, disturbed gait, and profound cognitive disability. Comparisons among sialyltransferase mutant mice provide insights into the functional roles of brain gangliosides and sialoglycoproteins consistent with related human congenital disorders.

Role of neuregulin-1/ErbB signaling in stem cell therapy for spinal cord injury-induced chronic neuropathic pain.

Chronic neuropathic pain is a common and debilitating consequence of spinal cord injury (SCI). In a rat contusion injury model, we observed that chronic neuropathic pain is present on day 7 after SCI and persists for the entire 56-day observation period. However, currently available pain therapies are inadequate for SCI-induced neuropathic pain. In this study, we show that spinal transplantation of mouse embryonic stem cell-derived oligodendrocyte progenitor cells (OPCs) enhances remyelination in the injured spinal cord and reduces SCI-induced chronic neuropathic pain. Moreover, we found that SCI reduces the protein level of neuregulin-1 and ErbB4 in the injured spinal cord and that OPC transplantation enhances the spinal expression of both proteins after SCI. Finally, intrathecal injection of neuregulin-1 small interfering RNA, but not the control nontarget RNA, diminishes OPC transplantation-produced remyelination and reverses the antinociceptive effect of OPC transplantation. Our findings suggest that the transplantation of embryonic stem cell-derived OPCs is an appropriate therapeutic intervention for treatment of SCI-induced chronic neuropathic pain, and that neuregulin-1/ErbB signaling plays an important role in central remyelination under pathological conditions and contributes to the alleviation of such pain.

Novel use of electromagnetic navigation for thoracostomy tube placement.

Management of recurrent pleural effusions can be challenging and may require multiple modalities for treatment. Advanced image guidance with ultrasound or computed tomography is often useful for increased accuracy. We demonstrate a novel application of a percutaneous image-guided technique using electromagnetic navigation to successfully place thoracostomy tubes.

Positron emission tomography for serial imaging of the contused adult rat spinal cord.

We investigated whether small-animal positron emission tomography (PET) could be used in combination with computed tomography (CT) imaging techniques for longitudinal monitoring of the injured spinal cord. In adult female Sprague-Dawley rats (n = 6), the ninth thoracic (T9) spinal cord segment was exposed by laminectomy and subsequently contused using the Infinite Horizon impactor (Precision System and Instrumentation, Lexington, KY) at 225 kDyn. In control rats (n = 4), the T9 spinal cord was exposed by laminectomy but not contused. At 0.5 hours and 3, 7, and 21 days postinjury, 2-[(18)F]fluoro-2-deoxy-d-glucose ([(18)F]FDG) was given intravenously followed 1 hour later by sequential PET and CT. Regions of interest (ROIs) at T9 (contused) and T6 (uninjured) spinal cord segments were manually defined on CT images and aided by fiduciary markers superimposed onto the coregistered PET images. Monte Carlo simulation revealed that about 33% of the activity in the ROIs was due to spillover from adjacent hot areas. A simulation-based partial-volume compensation (PVC) method was developed and used to correct for this spillover effect. With PET-CT, combined with PVC, we were able to serially measure standardized uptake values of the T9 and T6 spinal cord segments and reveal small, but significant, differences. This approach may become a tool to assess the efficacy of spinal cord repair strategies.

Ontogenetic changes in the morphology and morphometry of Cuban gar (Atractosteus tristoechus).

Detailed examination of early development and growth of Cuban gar (Atractosteus tristoechus) was conducted using morphologic and morphometric characters. Larvae were reared at a constant water temperature (28 ± 1°C) from hatching to 18 days after hatching (DAH). Observation of the disappearance, reduction, or appearance of external structures, pigment characteristics, and behavior, identified three developmental stages (attached 0-3 DAH; transitional 4-10 DAH; and free-swimming 11-18 DAH). For the 18 day trial, the average growth rate was 1.30 mm/d and the specific growth rate averaged 10.2%/d. The slowest growth rates (0.02 mm/d and 2.8%/d, 7-11 DAH) coincided with the exhaustion of yolk reserves and the transition from endogenous to exogenous feeding. In addition to the slowest growth rates, the most dramatic morphological changes in A. tristoechus were observed during the transition from endogenous to exogenous feeding. Five total length (TL) groupings were established using 25 morphologic and morphometic characters. The characters snout length, pelvic fin length, snout width at nares, head length, and head width best identified length groupings. As the larvae developed, the snout and head lengthened and narrowed. Proportionally, the snout was narrower and the head longer in Cuban gar larvae than in other lepisosteid larvae.

A lymphoproliferative pericardial mass.

Castleman disease (CD) is a rare lymphoproliferative disorder with variable presentation and prognosis. Most CD cases are unicentric and correspond to the hyaline-vascular variant, a histopathological classification associated with better outcomes, which commonly presents as an enhancing hypervascular mediastinal mass. CD is often asymptomatic and surgically resectable. Nonetheless, surgical resection can be difficult when the lymphoid mass is causing compression of vital structures. We discuss a rare case of hyaline-vascular unicentric CD presenting as an incidental pericardial mass.

Transgenic inhibition of astroglial NF-kappa B leads to increased axonal sparing and sprouting following spinal cord injury.

We previously showed that Nuclear Factor kappaB (NF-kappaB) inactivation in astrocytes leads to improved functional recovery following spinal cord injury (SCI). This correlated with reduced expression of pro-inflammatory mediators and chondroitin sulfate proteoglycans, and increased white matter preservation. Hence we hypothesized that inactivation of astrocytic NF-kappaB would create a more permissive environment for axonal sprouting and regeneration. We induced both contusive and complete transection SCI in GFAP-Inhibitor of kappaB-dominant negative (GFAP-IkappaBalpha-dn) and wild-type (WT) mice and performed retrograde [fluorogold (FG)] and anterograde [biotinylated dextran amine (BDA)] tracing 8 weeks after injury. Following contusive SCI, more FG-labeled cells were found in motor cortex, reticular formation, and raphe nuclei of transgenic mice. Spared and sprouting BDA-positive corticospinal axons were found caudal to the lesion in GFAP-IkappaBalpha-dn mice. Higher numbers of FG-labeled neurons were detected immediately rostral to the lesion in GFAP-IkappaBalpha-dn mice, accompanied by increased expression of synaptic and axonal growth-associated molecules. After transection, however, no FG-labeled neurons or BDA-filled axons were found rostral and caudal to the lesion, respectively, in either genotype. These data demonstrated that inhibiting astroglial NF-kappaB resulted in a growth-supporting terrain promoting sparing and sprouting, rather than regeneration, of supraspinal and propriospinal circuitries essential for locomotion, hence contributing to the improved functional recovery observed after SCI in GFAP-IkappaBalpha-dn mice.

Creation of highly aligned electrospun poly-L-lactic acid fibers for nerve regeneration applications.

Aligned, electrospun polymer fibers have shown considerable promise in directing regenerating axons in vitro and in vivo. However, in several studies, final electrospinning parameters are presented for producing aligned fiber scaffolds, and alignment where minimal fiber crossing occurs is not achieved. Highly aligned species are necessary for neural tissue engineering applications to ensure that axonal extension occurs through a regenerating environment efficiently. Axonal outgrowth on fibers that deviate from the natural axis of growth may delay axonal extension from one end of a scaffold to the other. Therefore, producing aligned fiber scaffolds with little fiber crossing is essential. In this study, the contributions of four electrospinning parameters (collection disk rotation speed, needle size, needle tip shape and syringe pump flow rate) were investigated thoroughly with the goal of finding parameters to obtain highly aligned electrospun fibers made from poly-L-lactic acid (PLLA). Using an 8 wt% PLLA solution in chloroform, a collection disk rotation speed of 1000 revolutions per minute (rpm), a 22 gauge, sharp-tip needle and a syringe pump rate of 2 ml h(-1) produced highly aligned fiber (1.2-1.6 microm in diameter) scaffolds verified using a fast Fourier transform and a fiber alignment quantification technique. Additionally, the application of an insulating sheath around the needle tip improved the rate of fiber deposition (electrospinning efficiency). Optimized scaffolds were then evaluated in vitro using embryonic stage nine (E9) chick dorsal root ganglia (DRGs) and rat Schwann cells (SCs). To demonstrate the importance of creating highly aligned scaffolds to direct neurite outgrowth, scaffolds were created that contained crossing fibers. Neurites on these scaffolds were directed down the axis of the aligned fibers, but neurites also grew along the crossed fibers. At times, these crossed fibers even stopped further axonal extension. Highly aligned PLLA fibers generated under optimized electrospinning conditions guided neurite and SC growth along the aligned fibers. Schwann cells demonstrated the bipolar phenotype seen along the fibers. Using a novel technique to determine fiber density, an increase in fiber density correlated to an increase in the number of neurites, but average neurite length was not statistically different between the two different fiber densities. Together, this work presents methods by which to produce highly aligned fiber scaffolds efficiently and techniques for assessing neurite outgrowth on different fiber scaffolds, while suggesting that crossing fibers may be detrimental in fostering efficient, directed axonal outgrowth.

Deoxyribozyme-mediated knockdown of xylosyltransferase-1 mRNA promotes axon growth in the adult rat spinal cord.

In the injured spinal cord, proteoglycans (PGs) within scar tissue obstruct axon growth through their glycosaminoglycan (GAG)-side chains. The formation of GAG-side chains (glycosylation) is catalysed by xylosyltransferase-1 (XT-1). Here, we knocked down XT-1 mRNA using a tailored deoxyribozyme (DNAXTas) and hypothesized that this would decrease the amount of glycosylated PGs and, consequently, promote axon growth in the adult rat spinal cord. A continuous 2-week delivery of DNAXTas near the rostral border of a peripheral nerve graft bridging the transected dorsal columns in the thoracic spinal cord resulted in an 81% decrease in XT-1 mRNA, an average of 1.4-fold reduction in GAG-side chains of chondroitin sulphate or heparan sulphate-PGs and 2.2-fold reduction in neurocan and brevican core proteins in scar tissue. Additionally, compared to control deoxyribozyme, the DNAXTas treatment resulted in a 9-fold increase in length and a 4-fold increase in density of ascending axons growing through the nerve graft and scar tissue present at the rostral spinal cord. Together our data showed that treatment with a deoxyribozyme against XT-1 mRNA decreased the amount of glycosylated PGs and promoted axon growth through scar tissue in the injured spinal cord. The deoxyribozyme approach may become a contributing factor in spinal cord repair strategies.

Stem cell-based therapies for spinal cord injury.

Spinal cord injury (SCI) results in loss of nervous tissue and consequently loss of motor and sensory function. There is no treatment available that restores the injury-induced loss of function to a degree that an independent life can be guaranteed. Transplantation of stem cells or progenitors may support spinal cord repair. Stem cells are characterized by self-renewal and their ability to become any cell in an organism. Promising results have been obtained in experimental models of SCI. Stem cells can be directed to differentiate into neurons or glia in vitro, which can be used for replacement of neural cells lost after SCI. Neuroprotective and axon regeneration-promoting effects have also been credited to transplanted stem cells. There are still issues related to stem cell transplantation that need to be resolved, including ethical concerns. This paper reviews the current status of stem cell application for spinal cord repair.

Índices de obesidad en mujeres con cáncer de mama del Cauca, Colombia / Obesity Indices in Women with Breast Cancer in Cauca, Colombia / Índices de obesidade entre mulheres com câncer de mama em Cauca, Colômbia

Resumen: Introducción: Algunos estudios permiten identificar que el cáncer de mama tiene orígenes multicausales y dentro de ellos se encuentran los trastornos derivados asociados a la grasa corporal, el objetivo fue identificar el nivel de sobrepeso u obesidad a través de índices de adiposidad en mujeres con cáncer de mama del departamento del Cauca. Material y métodos: estudio descriptivo correlacional, con 126 mujeres diagnosticadas con cáncer de mama. Las medidas para el análisis de la grasa corporal fueron el índice de conicidad, adiposidad, volumen abdominal y la ecuación CUN BAE, IMC, perímetros de cintura y cadera, se procesó en SPSS, obteniendo medidas de tendencia central y dispersión, como el estadístico de Pearson con una significancia p < 0,05, y la curva ROC (Receiver Operating Characteristic), para determinar la sensibilidad y la especificidad de las pruebas de adiposidad, atendiendo los aspectos éticos y legales. Resultados: el 31,78 %, de las evaluadas presentaron cáncer tipo IIb, invasivo en ganglios axilares, con una edad de la menarquia de 13,50±2,33 años. Se observó un promedio de sobrepeso según el IMC de 26,91±4,87 Kg/m2, respecto al perímetro de cintura (46.02 %) y el ICC (58.72 %) no manifestaron riesgo en estas variables; se identificaron correlaciones positivas muy altas entre el perímetro de cintura y los índices de adiposidad (R=0,992), índice de conicidad (R=0,858) y el ICC (R=0,845). Conclusiones: se pudo establecer que un alto porcentaje de mujeres con cáncer de mama presentó sobrepeso, identificando situaciones de riesgo asociadas con la grasa acumulada alrededor de la cintura, que se relaciona con otros índices de adiposidad, la herramienta identificada como útil correspondió al índice de conicidad con significancia estadística.

Abstract: Introduction: Obesity has become a problem that accentuates cancer processes. So the objective was to identify the level of obesity through adiposity indices in women with breast cancer in the department of Cauca-Colombia. Material and Methods: A correlational descriptive study with 126 women diagnosed with breast cancer. The measures for the analysis of body adiposity were the conicity index, body adiposity, abdominal volume, and the CUN BAE equation, body mass index, waist and hip circumferences. The data collected were processed in SPSS, obtaining measures of central tendency and dispersion, such as the Pearson statistic with a significance of p< 0.05 and the Receiver Operating Characteristic (ROC) curve to determine the sensitivity and specificity of adiposity tests, considering ethical and legal aspects. Results: 31.78% of women evaluated presented type IIb cancer. Invasive cancer in axillary lymph nodes, with menarche ages 13.50±2.33 years. An overweight average was observed according to a BMI of 26.91±4.87 Kg/m2. Concerning the waist circumference (46.02%) and the ICC (58.72%), they did not show risk in these variables. Very high positive correlations were identified between waist circumference and adiposity indices (R=0.992), conicity index (R=0.858), and WHR (R=0.845). Conclusions: It was possible to establish that a high percentage of women with breast cancer were overweight, identifying risk situations related to the fat accumulated around the waist, which is related to other adiposity indices. The tool identified as useful corresponded to the index of conicity with statistical significance.

Resumo: Introdução: A obesidade tornou-se um problema que acentua os processos de câncer. O objetivo era identificar o nível de obesidade através de índices de adiposidade em mulheres com câncer de mama no departamento do Cauca, Colômbia. Material e Métodos: Estudo descritivo correlacional, com 126 mulheres diagnosticadas com câncer de mama. As medidas para a análise da adiposidade corporal foram o índice de conicidade, adiposidade corporal, volume abdominal e a equação CUN BAE, índice de massa corporal, perímetros de cintura e quadril. Os dados foram processados no SPSS, obtendo-se medidas de tendência central e dispersão como a estatística de Pearson com um significado p<0,05, como a curva ROC (Receiver Operating Characteristic), para determinar a sensibilidade e especificidade dos testes de adiposidade, considerando os aspectos éticos e legais. Resultados: 31,78% das mulheres avaliadas tinham câncer tipo IIb, câncer invasivo nos gânglios axilares, com idade na menarca de 13,50±2,33 anos. Foi observado um excesso de peso médio de 26,91±4,87 kg/m2 com base no IMC, com relação ao perímetro da cintura (46,02%) e ICC (58,72%) não mostrou risco nestas variáveis; foram identificadas correlações positivas muito altas entre o perímetro da cintura e os índices de adiposidade (R=0,992), Índice de Conicidade (R=0,858) e ICC (R=0,845). Conclusões: Foi possível estabelecer que uma alta porcentagem de mulheres com câncer de mama estava com sobrepeso, identificando situações de risco relacionadas à gordura acumulada ao redor da cintura, que está relacionada a outros índices de adiposidade. A ferramenta identificada como útil correspondeu ao índice de conicidade com significância estatística.

Prevalencia y factores asociados a sobrepeso y obesidad en docentes de una universidad pública de Popayán- Colombia en 2021 / Prevalence and factors associated with overweight and obesity in teachers at a public university in Popayán-Colombia in 2021

Introducción: la prevalencia de la obesidad sigue en aumento a nivel mundial, lo que se traduce en un mayor riesgo para adquirir enfermedades no trasmisibles. Los factores de riesgos modificables que contribuyen a este problema, se asocian a situaciones laborales en cuyas condiciones de trabajo existe bajo dinamismo musculoesquelético. El objetivo de este estudio fue determinar la prevalencia y los factores asociados a la obesidad y el sobrepeso en docentes de una universidad pública del departamento del Cauca, Colombia en 2021. Metodología: estudio cuantitativo, de corte transversal; se seleccionaron 256 docentes. Se excluyeron profesores en periodo postquirúrgico abdominal reciente o con liposucción de abdomen. Se aplicó una encuesta indagando sobre datos sociodemográficos, conocimiento sobre obesidad y sobrepeso, hábitos y medidas antropométricas. Se realizó análisis descriptivo, pruebas de Chi cuadrado y regresión logística múltiple. Resultados: 47,7% de los docentes fueron clasificados con sobrepeso; 49,6% manifestó consumir bebidas alcohólicas; 18,4% presentó alto riesgo de enfermedad cardiovascular y 48,4% se encontraba en riesgo de presentar síndrome metabólico. Por su parte, los docentes hombres presentan mayor oportunidad de tener exceso de peso (OR: 2,16 IC: 95% 1,22-3,81), en comparación con las docentes mujeres. A su vez, aquellos docentes que comen entre las tres comidas principales, la oportunidad de presentar alto riesgo de enfermedad cardiovascular es 69% menor (OR:0,31 IC:95% 0,15-0,65). Conclusiones: los docentes universitarios de género masculino tienen mayor prevalencia de obesidad y sobrepeso, alto riesgo de adquirir una enfermedad cardiovascular y mayor riesgo cardiovascular en comparación con las mujeres, siendo de causa multifactorial.

Introduction: the prevalence of obesity continues to increase worldwide, which translates into a greater risk of acquiring non- communicable diseases. Modifiable risk factors, which contribute to this problem, are associated with work situations in which working conditions exist under musculoskeletal dynamism. The objective of this study was to determine the prevalence and factors associated with obesity and overweight in teachers of a public university in the department of Cauca, Colombia in 2021. Methodology: quantitative, cross-sectional study; 256 teachers were selected. Professors in the recent abdominal post-surgical period or with abdominal liposuction were excluded. A survey was applied inquiring about sociodemographic data, knowledge about obesity and overweight, habits and anthropometric measurements. Descriptive analysis, Chi square tests and multiple logistic regression were performed. Results: 47.7% of the teachers were classified as overweight; 49.6% stated that they consumed alcoholic beverages; 18.4% had a high risk of cardiovascular disease and 48.4% were at risk of presenting metabolic syndrome. For their part, male teachers have a greater chance of being overweight (OR: 2.16 CI: 95% 1.22-3.81), compared to female teachers. In turn, those teachers who eat between the three main meals, the chance of presenting a high risk of cardiovascular disease is 69% lower (OR:0.31 CI:95% 0.15-0.65). Conclusions: male university professors have a higher prevalence of obesity and overweight, high risk of acquiring cardiovascular disease and higher cardiovascular risk compared to women, being of multifactorial cause.

The complete mitochondrial DNA of the Cuban gar (Atractosteus tristoechus).

The Cuban gar (Atractosteus tristoechus) is an endemic lepisosteid living in Cuba. Among gars, this species is one of the most threatened and has the smallest natural distribution range. Lepisosteids are air-breathing fishes belonging to the Holostean, a basal non-teleost clade of actinopterygians. Recent studies have indicated that these fishes could be a 'bridge between tetrapods and teleost biomedical models'. Herein, we sequenced and assembled the first complete mitochondrial genome of A. tristoechus. The total length of the mt genome is 16,290 bp, containing the typical 13 protein-coding genes, two ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and a 537 bp length control region.

[Risk and physical activity level in adults in a healthy lifestyle program in Popayán]. / Riesgo y nivel de actividad física en adultos, en un programa de estilos de vida saludables en Popayán.

OBJECTIVE: To characterize risk and physical activity level of the participants in a program of healthy habits and lifestyles in the city of Popayán during the first semester of 2015. METHODS: Cross-sectional study on the adult population participating in a health promotion program developed by the Cauca Governor's Office with 500 users. Information was collected through the IPAQ questionnaire and risk for physical exercise was classified using the PAR-Q questionnaire. RESULTS: The results show a prevalence of 18.3 % for moderate and vigorous physical activity. The population group with the highest percentage of physical activity was found in young adults (aged 18-35 years), while 64 % of the population are at high risk regarding practicing physical exercise. CONCLUSIONS: The results obtained show that most of the population is at high risk regarding physical activity and also confirm low levels of moderate and vigorous physical activity. However, they also show signs of the importance of making evaluations prior to developing physical activity programs, such as security measures and control and monitoring of health status of the users.

OBJETIVO: Caracterizar el riesgo y el nivel de actividad física de los participantes de un programa de hábitos y estilos de vida saludables en el municipio de Popayán, durante el primer semestre de 2015. MÉTODOS: Estudio descriptivo de corte transversal, en la población adulta que participa en un programa de promoción de la Salud de la Gobernación del Cauca que acoge una población de 500 usuarios de las comunas 1 y 3. La información se colectó a través del cuestionario IPAQ, además de estratificar el riesgo para la práctica de ejercicio físico con el cuestionario PAR-Q. RESULTADOS: Los resultados arrojan una prevalencia de 18,3 % para actividad física vigorosa y moderada, el grupo poblacional que mayor porcentaje de actividad física realizo fue el adulto joven (18-35 años), el 64 % de la población se encuentran en riesgo alto para la práctica de ejercicio físico. CONCLUSIONES: Los resultados obtenidos estratifican a la mayoría de la población en alto riesgo para la práctica de ejercicio físico y confirman bajos niveles de actividad física entre moderada y vigorosa, pero dejan entrever la importancia de la realización de evaluaciones previas a la vinculación a programas de ejercicio físico, como medidas de seguridad, control y seguimiento del estado de salud en los usuarios.

Salud Mental, hábitos de sueño y nivel de actividad física en estudiantes de medicina en la educación virtual / Mental health, sleep habits and level of physical activity in medical students in virtual education

Resumen Introducción: el aislamiento trajo consigo cambios metodológicos en el desarrollo de los planes de estudio tradicionales a estrategias educativas virtuales, lo que pudo afectar la salud mental, hábitos de sueño y los niveles de actividad física durante la pandemia por COVID-19 en los estudiantes universitarios. Objetivo: determinar el estado de salud mental, los hábitos de sueño y el nivel de actividad física durante la educación virtual por COVID-19 en estudiantes del programa de medicina de una universidad pública en el departamento del Cauca. Método: estudio descriptivo, realizado a 268 estudiantes del programa de medicina seleccionados mediante muestreo no probabilístico, quienes diligenciaron una encuesta a través de la plataforma de cuestionarios de Google, la cual contenía 54 preguntas divididas en tres componentes: características demográficas y de aislamiento; estado de la salud mental; hábitos de sueño y nivel de actividad física. Resultados: el 58,6% de la población estudiantil sintió cansancio sin razón aparente; el 41,8% algunas veces presentó dificultad para conciliar el sueño; más de la mitad de la población presentó cambios de humor; el 48,5% (n=130) no realizaron actividad física. Además, se encontró relación entre salud mental y hábitos de sueño, hallándose significancia estadística entre ansiedad y alteración en el apetito. Conclusiones: la educación virtual durante la pandemia, produjo produjo alteraciones en los hábitos de sueño, cambios de humor (tristeza, ansiedad, irritabilidad y miedo), un bajo nivel de actividad física, además, se encontró relación entre los cambios emocionales, el apetito y los hábitos de sueño.

Abstract Introduction: isolation brought methodological changes in the development of traditional study plans to virtual educational strategies, which could affect mental health, sleep habits and physical activity levels during the COVID-19 pandemic in university students. Objective: to determine the mental health status, sleep habits and level of physical activity during virtual education by COVID-19 in undergraduate students of the medical program of a public university in the department of Cauca. Method: descriptive study, conducted with 268 students from the medicine program selected by non-probabilistic sampling, who filled out a survey through the Google questionnaire platform, which contained 54 questions divided into three components: demographic and isolation characteristics; mental health status; sleeping habits and level of physical activity. Results: 58.6% of the student population felt tired for no apparent reason; 41.8% sometimes had difficulty falling asleep; more than half of the population presented mood swings; 48.5% (n=130) did not perform physical activity. In addition, a relationship was found between mental health and sleep habits, finding statistical significance between anxiety and changes in appetite. Conclusions: virtual education during the pandemic, produced alterations in sleep habits, mood changes (sadness, anxiety, irritability and fear), a low level of physical activity, in addition, a relationship was found between emotional changes, appetite and sleep habits.

Descripción de la discapacidad y sus determinantes en personas con hemiparesia/hemiplejia del suroccidente de Colombia / Description of disability and its determinants in people with hemiparesia/hemiplegia in southwestern of Colombia / Descrição da deficiência e seus determinantes em pessoas com hemiparesia/hemiplegia do sul ocidente da Colômbia

Resumen Objetivo: el propósito del estudio fue conocer el grado de discapacidad y sus determinantes socioeconómicos, clínicos y de acceso a los servicios de salud y rehabilitación en personas con hemiplejía o hemiparesia en la ciudad de Popayán, Cauca. Metodología: estudio descriptivo, correlacional y transversal. Participaron 52 personas mayores de edad, con hemiplejia o hemiparesia. Se aplicó el cuestionario de evaluación de la discapacidad WHODAS 2.0. Resultados: El 100 % de las personas estudiadas tiene discapacidad, el promedio total de discapacidad fue de 44,7 %, correspondiente a discapacidad moderada. Los participantes mostraron dificultades en todos los dominios de funcionamiento, con dificultad moderada en los dominios cognición, cuidado personal, actividades cotidianas y dificultad severa para movilidad y participación. Conclusión: la hemiparesia y hemiplejia provocan discapacidad en diferentes grados de severidad, determinada por el estado patológico y la interacción e influencia de múltiples factores socioeconómicos, clínicos y de acceso a los servicios de salud y rehabilitación.

Abstract Objective: The purpose of the study was to determine the degree of disability and its socioeconomic and clinical determinants as well as the access to health and rehabilitation services in people with hemiplegia or hemiparesis in the city of Popayán, Cauca, Colombia. Methodology: descriptive, correlational and cross-sectional study. The sample consisted of 52 people of legal age, with a diagnosis of hemiplegia or hemiparesis. The WHODAS 2.0 disability assessment questionnaire was applied. Results: A hundred percent of the people studied had a disability, and the disability average total was 44.7%, corresponding to moderate disability. The participants showed difficulties in all domains of functioning, with moderate difficulty in the cognition, personal care and daily activities domains, and severe difficulty with mobility and participation. Conclusions: Hemiparesis and hemiplegia cause disability in different degrees of severity determined by the pathological state and the interaction and the influence of multiple socioeconomic, clinical factors and access to health and rehabilitation services.

Resumo Objetivo: o propósito do estudo foi conhecer o grau de deficiência e seus determinantes socioeconômicos, clínicos e de aceso aos serviços de saúde e reabilitação em pessoas com hemiplegia ou hemiparesia na cidade de Popayán, Cauca. Metodologia: estudo descritivo, correlacional e transversal. Participaram 52 pessoas maiores de idade, com hemiplegia ou hemiparesia. Aplicou-se o questionário de avaliação da deferência WHODAS 2.0. Resultados: O 100 % das pessoas estudadas tem deficiência, a média total de deficiência foi de 44,7 %, correspondente à deficiência moderada. Os participantes amostraram dificuldades em todos os domínios de funcionamento, com dificuldade moderada nos domínios cognição, cuidado pessoal, atividades cotidianas e dificuldade severa para mobilidade e participação. Conclusão: a hemiparesia e hemiplegia provocam deficiência em diferentes graus de severidade, determinada pelo estado patológico e a interação e influência de múltiplos fatores socioeconômicos, clínicos e de aceso aos serviços de saúde e reabilitação.

Poly (D,L-lactic acid) macroporous guidance scaffolds seeded with Schwann cells genetically modified to secrete a bi-functional neurotrophin implanted in the completely transected adult rat thoracic spinal cord.

Freeze-dried poly(D,L-lactic acid) macroporous scaffold filled with a fibrin solution containing Schwann cells (SCs) lentivirally transduced to produce and secrete D15A, a bi-functional neurotrophin with brain-derived neurotrophic factor and neurotrophin-3 activity, and to express green fluorescent protein (GFP) were implanted in the completely transected adult rat thoracic spinal cord. Control rats were similarly injured and then implanted with scaffolds containing the fibrin solution with SCs lentivirally transduced to produce express GFP only or with the fibrin solution only. Transgene production and biological activity in vitro, SC survival within the scaffold in vitro and in vivo, scaffold integration, axonal regeneration and myelination, and hind limb motor function were analyzed at 1, 2, and 6 weeks after implantation. In vitro, lentivirally transduced SCs produced 87.5 ng/24 h/10(6) cells of D15A as measured by neurotrophin-3 activity in ELISA. The secreted D15A was biologically active as evidenced by its promotion of neurite outgrowth of dorsal root ganglion neurons in culture. In vitro, SCs expressing GFP were present in the scaffolds for up to 6 h, the end of a typical surgery session. Implantation of SC-seeded scaffolds caused modest loss of spinal nervous tissue. Reactive astrocytes and chondroitin sulfate glycosaminoglycans were present in spinal tissue adjacent to the scaffold. Vascularization of the scaffold was ongoing at 1 week post-implantation. There were no apparent differences in scaffold integration and blood vessel formation between groups. A decreasing number of implanted (GFP-positive) SCs were found within the scaffold during the first 3 days after implantation. Apoptosis was identified as one of the mechanisms of cell death. At 1 week and later time points after implantation, few of the implanted SCs were present in the scaffold. Neurofilament-positive axons were found in the scaffold. At 6 weeks post-grafting, myelinated axons were observed within and at the external surface of the scaffold. Axons did not grow from the scaffold into the caudal cord. All groups demonstrated a similar improvement of hind limb motor function. Our findings demonstrated that few seeded SCs survived in vivo, which could account for the modest axonal regeneration response into and across the scaffold. For the development of SC-seeded macroporous scaffolds that effectively promote axonal regeneration in the injured spinal cord, the survival and/or total number of SCs in the scaffold needs to be improved.

Bone marrow stromal cells for repair of the spinal cord: towards clinical application.

Stem cells have been recognized and intensively studied for their potential use in restorative approaches for degenerative diseases and traumatic injuries. In the central nervous system (CNS), stem cell-based strategies have been proposed to replace lost neurons in degenerative diseases such as Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis (Lou Gehrig's disease), or to replace lost oligodendrocytes in demyelinating diseases such as multiple sclerosis. Stem cells have also been implicated in repair of the adult spinal cord. An impact to the spinal cord results in immediate damage to tissue including blood vessels, causing loss of neurons, astrocytes, and oligodendrocytes. In time, more tissue nearby or away from the injury site is lost due to secondary injury. In case of relatively minor damage to the cord some return of function can be observed, but in most cases the neurological loss is permanent. This review will focus on in vitro and in vivo studies on the use of bone marrow stromal cells (BMSCs), a heterogeneous cell population that includes mesenchymal stem cells, for repair of the spinal cord in experimental injury models and their potential for human application. To optimally benefit from BMSCs for repair of the spinal cord it is imperative to develop in vitro techniques that will generate the desired cell type and/or a large enough number for in vivo transplantation approaches. We will also assess the potential and possible pitfalls for use of BMSCs in humans and ongoing clinical trials.

Local Release of Paclitaxel from Aligned, Electrospun Microfibers Promotes Axonal Extension.

Traumatic spinal cord injuries ultimately result in an inhibitory environment that prevents axonal regeneration from occurring. A low concentration administration of paclitaxel has been previously shown to promote axonal extension and attenuate the upregulation of inhibitory molecules after a spinal cord injury. In this study, paclitaxel is incorporated into electrospun poly(l-lactic acid) (PLA) microfibers, and it is established that a local release of paclitaxel from aligned, electrospun microfibers promotes neurite extension in a growth-conducive and inhibitory environment. Isolated dorsal root ganglion cells are cultured for 5 d directly on tissue culture polystyrene surface, PLA film, random, or aligned electrospun PLA microfibers (1.44 ± 0.03 µm) with paclitaxel incorporated at various concentrations (0%-5.0% w/w in reference to fiber weight). To determine the effect of a local release of paclitaxel, paclitaxel-loaded microfibers are placed in CellCrown inserts above cultured neurons. Average neurite extension rate is quantified for each sample. A local release of paclitaxel maintains neuronal survival and neurite extension in a concentration-dependent manner when coupled with aligned microfibers when cultured on laminin or an inhibitory surface of aggrecan. The findings provide a targeted approach to improve axonal extension across the inhibitory environment present after a traumatic injury in the spinal cord.