Feocromocitoma y Paraganglioma: un reto más allá de la clínica / Pheochromocytoma and Paraganglioma: a Challenge beyond the Clinic

Resumen Los feocromocitomas y paragangliomas son tumores raros que se originan en las células cromafines. Tienen un amplio espectro clínico que va desde el hallazgo incidental hasta manifestaciones por la producción exagerada de catecolaminas. El diagnóstico bioquímico se realiza mediante medición de metanefrinas libres en plasma. El tratamiento ideal es la escisión quirúrgica completa previo bloqueo de receptores a y 6 adrenérgicos. En caso de enfermedad metastásica, las opciones de tratamiento sistêmico actuales son limitadas y con escasa tasa de respuesta. Está en investigación el uso de antiangiogénicos.

Abstract Pheochromocytomas and Paragangliomas are rare tumors, originated from the chromaffin cells. They have a broad clinical spectrum from incidental finding to full clinical manifestations explain to overproduction of catecholamines. The biochemistry diagnosis is made by the measurement of free Metanephrines in plasma. Complete surgical removal is the optimal treatment, previously having a y 6 adrenergic receptors blockage. In case of metastasic disease, treatment options are palliative, limited and with a low rate response; the use of antiangiogenic treatments is under investigation.

Evaluation of PVA biodegradable electric conductive membranes for nerve regeneration in axonotmesis injuries: the rat sciatic nerve animal model.

The therapeutic effect of three polyvinyl alcohol (PVA) membranes loaded with electrically conductive materials - carbon nanotubes (PVA-CNTs) and polypyrrole (PVA-PPy) - were tested in vivo for neuro-muscular regeneration after an axonotmesis injury in the rat sciatic nerve. The membranes electrical conductivity measured was 1.5 ± 0.5 × 10-6 S/m, 579 ± 0.6 × 10-6 S/m, and 1837.5 ± 0.7 × 10-6 S/m, respectively. At week-12, a residual motor and nociceptive deficit were present in all treated groups, but at week-12, a better recovery to normal gait pattern of the PVA-CNTs and PVA-PPy treated groups was observed. Morphometrical analysis demonstrated that PVA-CNTs group presented higher myelin thickness and lower g-ratio. The tibialis anterior muscle, in the PVA-PPy and PVA-CNTs groups showed a 9% and 19% increase of average fiber size area and a 5% and 10% increase of the "minimal Feret's diameter," respectively. No inflammation, degeneration, fibrosis or necrosis were detected in lung, liver, kidneys, spleen, and regional lymph nodes and absence of carbon deposits was confirmed with Von Kossa and Masson-Fontana stains. In conclusion, the membranes of PVA-CNTs and PVA-PPy are biocompatible and have electrical conductivity. The higher electrical conductivity measured in PVA-CNTs membrane might be responsible for the positive results on maturation of myelinated fibers. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1267-1280, 2017.

Evaluation of biodegradable electric conductive tube-guides and mesenchymal stem cells.

AIM: To study the therapeutic effect of three tube-guides with electrical conductivity associated to mesenchymal stem cells (MSCs) on neuro-muscular regeneration after neurotmesis. METHODS: Rats with 10-mm gap nerve injury were tested using polyvinyl alcohol (PVA), PVA-carbon nanotubes (CNTs) and MSCs, and PVA-polypyrrole (PPy). The regenerated nerves and tibialis anterior muscles were processed for stereological studies after 20 wk. The functional recovery was assessed serially for gait biomechanical analysis, by extensor postural thrust, sciatic functional index and static sciatic functional index (SSI), and by withdrawal reflex latency (WRL). In vitro studies included cytocompatibility, flow cytometry, reverse transcriptase polymerase chain reaction and karyotype analysis of the MSCs. Histopathology of lung, liver, kidneys, and regional lymph nodes ensured the biomaterials biocompatibility. RESULTS: SSI remained negative throughout and independently from treatment. Differences between treted groups in the severity of changes in WRL existed, showing a faster regeneration for PVA-CNTs-MSCs (P < 0.05). At toe-off, less acute ankle joint angles were seen for PVA-CNTs-MSCs group (P = 0.051) suggesting improved ankle muscles function during the push off phase of the gait cycle. In PVA-PPy and PVA-CNTs groups, there was a 25% and 42% increase of average fiber area and a 13% and 21% increase of the "minimal Feret's diameter" respectively. Stereological analysis disclosed a significantly (P < 0.05) increased myelin thickness (M), ratio myelin thickness/axon diameter (M/d) and ratio axon diameter/fiber diameter (d/D; g-ratio) in PVA-CNT-MSCs group (P < 0.05). CONCLUSION: Results revealed that treatment with MSCs and PVA-CNTs tube-guides induced better nerve fiber regeneration. Functional and kinematics analysis revealed positive synergistic effects brought by MSCs and PVA-CNTs. The PVA-CNTs and PVA-PPy are promising scaffolds with electric conductive properties, bio- and cytocompatible that might prevent the secondary neurogenic muscular atrophy by improving the reestablishment of the neuro-muscular junction.

Síndrome de apnea/hipopnea obstructiva del sueño y su asociación con las enfermedades cardiovasculares / Obstructive Sleep Apnea Hypopnea Syndrome and its association with cardiovascular disease

Introducción:El síndrome de apnea/hipopnea obstructiva del sueño, es una entidad que ha cobrado importancia en los últimos años, con una prevalencia estimada en adultos de edad media cercana al 4 y al 2% en hombres y mujeres, respectivamente, y que por su frecuencia constituye un problema de salud pública. Objetivo:Exponer, tras un análisis exhaustivo de la literatura disponible, la asociación entre el síndrome de apnea/hipopnea obstructiva del sueño y las enfermedades cardiovasculares. Método: Se hizo una revisión narrativa a partir de la literatura encontrada en las bases de datos más reconocidas. Se incluyeron 59 estudios publicados en los últimos treinta años y se excluyeron reportes y series de casos. Conclusiones: El síndrome de apnea/hipopnea obstructiva del sueño se reconoce hoy en día como un problema de salud pública mundial. En Latinoamérica, más específicamente en Colombia, se requieren estudios prospectivos de cohorte que sirvan de pauta para la población del continente e indiquen posibles diferencias respecto a la comunidad internacional en cuanto a su tratamiento y diagnóstico oportunos, así como acerca del impacto de estos en lo concerniente a los desenlaces cardiovasculares de los pacientes.

Introduction: The Obstructive Sleep Apnea Hypopnea Syndrome has gained importance has gained importance in recent years, with an estimated prevalence in population of middle-aged adults around 4 and 2% in men and women respectively, and that given its frequency constitutes a public health problem. Objective: To show, after a thorough analysis of the available literature, the association between the Obstructive Sleep Apnea Hypopnea Syndrome and cardiovascular diseases. Method: A narrative review was made from the literature found at the most recognized databases. Fifty nine studies published in the last thirty years were included and reports and case series were excluded. Conclusions: The Obstructive Sleep Apnea Hypopnea Syndrome is recognized today as a global public health problem. Latin America, specifically Colombia, requires prospective cohort studies that serve as a guideline for the continent's population and that could indicate possible differences compared to the international community regarding early diagnosis and treatment, and its impact in cardiovascular outcomes of these patients.

Promoting nerve regeneration in a neurotmesis rat model using poly(DL-lactide-ε-caprolactone) membranes and mesenchymal stem cells from the Wharton's jelly: in vitro and in vivo analysis.

In peripheral nerves MSCs can modulate Wallerian degeneration and the overall regenerative response by acting through paracrine mechanisms directly on regenerating axons or upon the nerve-supporting Schwann cells. In the present study, the effect of human MSCs from Wharton's jelly (HMSCs), differentiated into neuroglial-like cells associated to poly (DL-lactide-ε-caprolactone) membrane, on nerve regeneration, was evaluated in the neurotmesis injury rat sciatic nerve model. Results in vitro showed successful differentiation of HMSCs into neuroglial-like cells, characterized by expression of specific neuroglial markers confirmed by immunocytochemistry and by RT-PCR and qPCR targeting specific genes expressed. In vivo testing evaluated during the healing period of 20 weeks, showed no evident positive effect of HMSCs or neuroglial-like cell enrichment at the sciatic nerve repair site on most of the functional and nerve morphometric predictors of nerve regeneration although the nociception function was almost normal. EPT on the other hand, recovered significantly better after HMSCs enriched membrane employment, to values of residual functional impairment compared to other treated groups. When the neurotmesis injury can be surgically reconstructed with an end-to-end suture or by grafting, the addition of a PLC membrane associated with HMSCs seems to bring significant advantage, especially concerning the motor function recovery.

Empiema Necessitatis / Empyema necessitatis

Se presenta el caso de un hombre de 73 años, agricultor, quien consulta por cuadro de tres meses de tos húmeda con expectoración verdosa, posteriormente hemoptoica, de predominio matutino, asociado a dolor lumbar izquierdo. Se documentó en imágenes empiema que se comunica con región lumbar izquierda, constituyendo así un cuadro de empiema necessitatis con presentación poco usual como lo es el drenaje hacia espacio paravertebral. (Acta Med Colomb 2013; 38: 28-31).

We present the case of a 73-year-old farmer, who consults for a 3 months clinical picture of wet cough with greenish sputum, subsequently hemoptoic predominantly in the mornings, associated with left lumbar pain. We documented in images empyema communicating with the left lumbar region, constituting an empyema necessitatis picture with unusual presentation as is the drainage to the paravertebral space. (Acta Med Colomb 2013; 38: 28-31).

Use of PLGA 90:10 scaffolds enriched with in vitro-differentiated neural cells for repairing rat sciatic nerve defects.

Poly(lactic-co-glycolic acid) (PLGA) nerve tube guides, made of a novel proportion (90:10) of the two polymers, poly(L-lactide): poly(glycolide) and covered with a neural cell line differentiated in vitro, were tested in vivo for promoting nerve regeneration across a 10-mm gap of the rat sciatic nerve. Before in vivo testing, the PLGA 90:10 tubes were tested in vitro for water uptake and mass loss and compared with collagen sheets. The water uptake of the PLGA tubes was lower, and the mass loss was more rapid and higher than those of the collagen sheets when immersed in phosphate-buffered saline (PBS) solution. The pH values of immersing PBS did not change after soaking the collagen sheets and showed to be around 7.4. On the other hand, the pH values of PBS after soaking PLGA tubes decreased gradually during 10 days reaching values around 3.5. For the in vivo testing, 22 Sasco Sprague adult rats were divided into four groups--group 1: gap not reconstructed; group 2: gap reconstructed using an autologous nerve graft; group 3: gap reconstructed with PLGA 90:10 tube guides; group 4: gap reconstructed with PLGA 90:10 tube guides covered with neural cells differentiated in vitro. Motor and sensory functional recovery was evaluated throughout a healing period of 20 weeks using sciatic functional index, static sciatic index, extensor postural thrust, withdrawal reflex latency, and ankle kinematics. Stereological analysis was carried out on regenerated nerve fibers. Both motor and sensory functions improved significantly in the three experimental nerve repair groups, although the rate and extent of recovery was significantly higher in the group where the gap was reconstructed using the autologous graft. The presence of neural cells covering the inside of the PLGA tube guides did not make any difference in the functional recovery. By contrast, morphometric analysis showed that the introduction of N1E-115 cells inside PLGA 90:10 tube guides led to a significant lower number and size of regenerated nerve fibers, suggesting thus that this approach is not adequate for promoting peripheral nerve repair. Further studies are warranted to assess the role of other cellular systems as a foreseeable therapeutic strategy in peripheral nerve regeneration.

Formação de professores: pequenas histórias, grandes personagens. Novas práticas e reconhecimento de novos saberes / Teacher training: small stories, great characters. New practices and recognition of new knowledge

O trabalho discute experiência em curso de formação universitária de professores. Permite reflexão sobre novo entendimento dos saberes oferecidos pela universidade, que alcançam alunos atuantes nas redes públicas e particular, em escolas de educação infantil e fundamental. No contexto atual, quando se discute o locus da formação - cursos de Pedagogia, institutos superiores de Educação e cursos normais médios - procura mostrar que a reflexão sobre tal formação ultrapassa o locus, alcançando o processo em si, envolvendo estratégias de formação do professor crítico-reflexivo. Ante a necessidade de oferecer a tais professores formação ampliada, mais importantes se tornam as contribuições à construção do ser, do saber e do fazer desse professor. A pesquisa apresenta-se como elemento integrador de dois focos de produção da realidade - pesquisador e pesquisados, validando estudos/resultados obtidos em construção coletiva do contexto que envolve a universidade e os espaços de atuação dos alunos-professores