Caracterización objetiva de la brecha aéreo-ósea con Potenciales Evocados Auditivos de Estado Estable en pacientes con hipoacusia conductiva

Introduction: The difference between the airway and the bone is a fundamental element for the differential diagnosis of hearing loss. Its evaluation with the Auditory Evoked Potentials is very important for the characterization of the hearing loss in the child, not being able to describe until the present moment an objective method that allows obtaining reliable results in pediatrics. Objective: To demonstrate the usefulness of Steady State Auditory Evoked Potentials in the objective characterization of the air-bone gap in pediatric patients with transmission hearing loss. Method: For this research, a descriptive study was carried out, in 11 children normal hearing (G1 = 15 ears) and 14 patients with conductive hearing loss (G2 = 15 ears). Behavioral and electrophysiological audiometric studies (steady state potentials) were performed. Results: The differences between the behavioral and electrophysiological results showed similar values ​​in the 2 explored groups (G1: 2-3 dB; G2 0-4 dB), obtaining a correlation value of 0.94 in the global analysis. Conclusion: The audiometry by means of auditory evoked potentials of stable state at multiple frequencies, scientifically reports an important objective audiological method that allows the characterization of the air-bone gap with which the different types of hearing loss in children can be differentiated.Introducción: La diferencia entre la vía aérea y ósea constituye un elemento fundamental para el diagnóstico diferencial de la hipoacusia. Su evaluación con los Potenciales Evocados Auditivos es muy importante para la caracterización de la pérdida auditiva en el niño, no lográndose describir hasta el momento actual un método objetivo que permita obtener resultados confiables en pediatría. Objetivo: Demostrar la utilidad de los Potenciales Evocados Auditivos de Estado Estable en la caracterización objetiva de la brecha aéreo-ósea en pacientes pediátricos con hipoacusia de transmisión. Método: Para esta investigación se realizó un estudio descriptivo, en 11 niños audición normal (G1=15 oídos) y 14 pacientes con hipoacusia conductiva (G2=15 oídos). Se realizaron estudios audiométricos conductuales y electrofisiológicos (potenciales de estado estable). Resultados: Las diferencias entre los resultados conductuales y electrofisiológicos, mostraron valores similares en los 2 grupos explorados (G1: 2-3 dB; G2 0-4 dB), obteniéndose un valor de correlación de 0.94 en el análisis global. Conclusión: La audiometría mediante potenciales evocados auditivos de estado estable a múltiples frecuencias, reporta científicamente un importante método audiológico objetivo que permite la caracterización de la brecha aéreo-ósea con la cual se pueden diferenciar los distintos tipos de hipoacusia en el niño

RETOS DE LOS ENSAYOS CLÍNICOS EN EL ADULTO MAYOR

Los logros del Sistema Nacional de Salud en Cuba y el descenso de la fecundidad han provocado en las últimas décadas un proceso de envejecimiento acelerado, alcanzando al cierre del 2020 la cifra de 21,3 % de la población con 60 años y más con un incremento de las enfermedades. El desarrollo de nuevas terapias y tecnologías para el diagnóstico e intervención en diversas áreas de la medicina hacen imprescindibles los ensayos clínicos, la participación del adulto mayor impone retos para su diseño y desarrollo. El objetivo de este trabajo es realizar una breve descripción de los retos que impone la participación de los adultos mayores en los ensayos clínicos. Para ello, se consultó la información publicada en la base de datos de PubMed. Se realizó un análisis de las dificultades que se presentan en las diferentes etapas de los ensayos clínicos y se enunciaron estrategias para mejorar la participación de los adultos mayores en estos estudios. Se concluye que es muy necesario promover el conocimiento y cumplimiento de las regulaciones establecidas para los ensayos clínicos en poblaciones mayores de 60 años, por parte de los investigadores que diseñan y participan en las evaluaciones clínicas de medicamentos y tecnologías médica

Evaluation of the potential of Mycobacterium smegmatis as vaccine Candidate against tuberculosis by in silico and in vivo studies

In this study, we scanned multiple published databases of gene expression in vivo of M. tuberculosis at different phases of infection in animals and humans, to select 38 proteins that are highly expressed in the active, latent and reactivation phases. The selected proteins were predicted for T and B epitopes. For each proteins, the regions containing T and B epitopes were selected at the same time to look for identical epitopes on M. smegmatis based on sequence alignments. Preliminary studies of humoral immunogenicity and cross-reactivity with M. tuberculosis in mice using two M. smegmatis-derived experimental vaccines were carried out, demonstrating the immunogenicity of M. smegmatis proteoliposomes and the recognition of M. tuberculosis proteins by the sera of animals immunized with this vaccine candidate. The conjunction of in silico and in vivo studies suggested the potential for future evaluation of M. smegmatis as vaccine candidate against tuberculosis using different strategie

Efectos en el Sistema Contable de XYZ Telecomunicaciones S.A., generados por la inestabilidad laboral

En el presente trabajo se pretende demostrar como la inestabilidad laboral en XYZ Telecomunicaciones S.A., (empresa objeto de estudio y de investigación) la afecta de manera directa cuando los empleados carecen de experiencia laboral debido a la alta rotación de personal la cual se ve reflejada en la calidad del trabajo realizado generando informes que carecen de confiabilidad, pertinencia y comparación, cualidades fundamentales de la contabilidad. Esto conduce a que se vea afectado el patrimonio de la organización debido a la toma de decisiones no acertadas que son tomadas con base a los informes generados por el sistema contable de la empresa. Nuestra investigación busca que los gerentes de cualquier empresa logren valorar que tan importante es el Recurso Humano en su organización y su estabilidad laboral como fuente de aprendizaje y de experiencia que sirva para el buen funcionamiento de la misma dentro de su SIC para la toma de decisiones.PregradoCONTADOR(A) PÚBLIC

Testing the connections within face processing circuitry in Capgras delusion with diffusion imaging tractography

Although Capgras delusion (CD) patients are capable of recognizing familiar faces, they present a delusional belief that some relatives have been replaced by impostors. CD has been explained as a selective disruption of a pathway processing affective values of familiar faces. To test the integrity of connections within face processing circuitry, diffusion tensor imaging was performed in a CD patient and 10 age-matched controls. Voxel-based morphometry indicated gray matter damage in right frontal areas. Tractography was used to examine two important tracts of the face processing circuitry: the inferior fronto-occipital fasciculus (IFOF) and the inferior longitudinal (ILF). The superior longitudinal fasciculus (SLF) and commissural tracts were also assessed. CD patient did not differ from controls in the commissural fibers, or the SLF. Right and left ILF, and right IFOF were also equivalent to those of controls. However, the left IFOF was significantly reduced respect to controls, also showing a significant dissociation with the ILF, which represents a selective impairment in the fiber-tract connecting occipital and frontal areas. This suggests a possible involvement of the IFOF in affective processing of faces in typical observers and in covert recognition in some cases with prosopagnosia

Validación de un ELISA para la cuantificación de IgG antipolisacárido capsular de Neisseria meningitidis serogrupo C en sueros de ratones.

Se desarrolló un ensayo inmunoenzimático de fase sólida (ELISA) indirecto para cuantificar anticuerpos IgG específicos antipolisacárido C en ratón, utilizando un prerrecubrimiento con Poli-L-lisina y luego el polisacárido capsular de Neisseria meningitidis serogrupo C (Instituto Finlay, La Habana, Cuba), para evaluar la respuesta inmune contra este componente en candidatos vacunales en estudios preclínicos. Como conjugado se utilizó anti-IgG ratón conjugado a fosfatasa alcalina, el cual se une a los anticuerpos antipolisacárido C producidos en ratones. La reacción es evidenciada por la degradación del sustrato p-nitrofenilfosfato. La detectibilidad del ensayo fue de 123,74 U/mL y la especificidad fue alta. La precisión interensayo, intraensayo y total, así como las desviaciones de la recuperación, linealidad y paralelismo no sobrepasaron el 10%. El ELISA permitió cuantificar los anticuerpos antipolisacárido C inducidos en ratones tanto por candidatos vacunales conjugados, como por la vacuna VA-MENGOC-BC y el polisacárido C sin conjugar

Specific and cross-reactive immune response against Mycobacterium tuberculosis antigens in mice immunized with proteoliposomes from Mycobacterium bovis BCG

Objective: To characterize the immunogenicity and the induction of cross-reactive responses against Mycobacterium tuberculosis (M. tuberculosis) of a proteoliposome (PL) from Mycobacterium bovis Bacillus Calmette–Guérin (BCG) with and without alum hydroxide (AL) as adjuvant (PLBCG-AL and PLBCG, respectively) in BALB/c mice. Methods: BALB/c mice were inoculated with phosphate buffer solution, BCG, PLBCG and PLBCG-AL. The humoral immunogenicity was determined by ELISA [immunoglobulin G (IgG), IgG1 and IgG2a] and the cellular immunogenicity was evaluated in vivo by delayed type hypersensitivity. The humoral cross-reactive response against M. tuberculosis was determined by Western blot. Results: Sera from animals immunized with PLBCG-AL and PLBCG showed significant increase in specific total IgG and IgG1 antibodies and the presence of cross-reactive antibodies against M. tuberculosis antigens, which were more intense with the use of alum as adjuvant. Mice immunized with PLBCG and PLBCG-AL also showed a specific cellular response in vivo. Conclusions: The cellular and humoral immunogenicity of PLBCG and the capacity to induce cross-reactive responses against M. tuberculosis is in agreement with the protective capacity previously demonstrated by this vaccine candidate and supports the continuation of its evaluation in further stages

Protective Effect of a Lipid-Based Preparation from Mycobacterium smegmatis in a Murine Model of Progressive Pulmonary Tuberculosis

A more effective vaccine against tuberculosis (TB) is urgently needed. Based on its high genetic homology with Mycobacterium tuberculosis (Mtb), the nonpathogenic mycobacteria, Mycobacterium smegmatis (Ms), could be an attractive source of potential antigens to be included in such a vaccine. We evaluated the capability of lipid-based preparations obtained from Ms to provide a protective response in Balb/c mice after challenge with Mtb H37Rv strain. The intratracheal model of progressive pulmonary TB was used to assess the level of protection in terms of bacterial load as well as the pathological changes in the lungs of immunized Balb/c mice following challenge with Mtb. Mice immunized with the lipid-based preparation from Ms either adjuvanted with Alum (LMs-AL) or nonadjuvanted (LMs) showed significant reductions in bacterial load (P<0.01) compared to the negative control group (animals immunized with phosphate buffered saline (PBS)). Both lipid formulations showed the same level of protection as Bacille Calmette and Guerin (BCG). Regarding the pathologic changes in the lungs, mice immunized with both lipid formulations showed less pneumonic area when compared with the PBS group (P<0.01) and showed similar results compared with the BCG group. These findings suggest the potential of LMs as a promising vaccine candidate against TB

Passive administration of purified secretory IgA from human colostrum induces protection against <it>Mycobacterium tuberculosis</it> in a murine model of progressive pulmonary infection

<p>Abstract</p> <p>Background</p> <p>Immunoglobulin A is the most abundant isotype in secretions from mucosal surfaces of the gastrointestinal, respiratory and genitourinary tracts and in external secretions such as colostrum, breast milk, tears and saliva. The high concentration of human secretory IgA (hsIgA) in human colostrum strongly suggests that it should play an important role in the passive immune protection against gastrointestinal and respiratory infections.</p> <p>Materials and methods</p> <p>Human secretory IgA was purified from colostrum. The reactivity of hsIgA against mycobacterial antigens and its protective capacity against mycobacterial infection was evaluated.</p> <p>Results</p> <p>The passive administration of hsIgA reduces the pneumonic area before challenge with <it>M.</it> tuberculosis. The intratracheal administration of <it>M. tuberculosis</it> preincubated with hsIgA to mice greatly reduced the bacterial load in the lungs and diminished lung tissue injury.</p> <p>Conclusions</p> <p>HsIgA purified from colostrum protects against <it>M. tuberculosis</it> infection in an experimental mouse model.</p