Cutaneous infection by Phaeoacremonium parasiticum / Infección cutánea por Phaeoacremonium parasiticum

Background: Phaeoacremonium parasiticum is considered a rare infectious agent that is part of a heterogeneous group of fungi causing phaeohyphomycosis. This organism is capable of producing subcutaneous infections, eumycetomas, osteomyelitis, arthritis, myositis and also disseminated diseases, such as fungemia and endocarditis. Case report: We describe a case of cutaneous infection by P. parasiticum in a kidney transplant patient. The identification of this microorganism was performed by microbiological and histopathological studies and confirmed with the sequence of the gene encoding β-tubulin and a real time panfungal PCR targeting 18S ribosomal RNA gene. The microorganism was correctly identified by phenotypic and molecular methods. The patient was treated with oral antifungal therapy and a debulking surgery and evolved without any complication. Conclusions: The diagnosis of this infection is difficult and usually affects kidney transplant patients, but the reasons of this association are still unknown

Antecedentes: Phaeoacremonium parasiticum es considerado un agente infeccioso poco común que forma parte de un grupo heterogéneo de hongos causantes de feohifomicosis. Este microorganismo es capaz de producir infección cutánea, eumicetoma, osteomielitis, artritis, miositis e incluso enfermedad diseminada como fungemia y endocarditis. Caso clínico: Se describe un caso de infección cutánea por P. parasiticum en un paciente trasplantado renal. Para la identificación del microorganismo se realizaron pruebas microbiológicas e histopatológicas, y se confirmó la identificación con la secuenciación del gen de la β-tubulina y una PCR a tiempo real para la detección del gen 18S rRNA. El microorganismo fue identificado correctamente por métodos fenotípicos y moleculares. El paciente recibió tratamiento con antifúngicos orales y citorreducción quirúrgica, y evolucionó sin ninguna complicación. Conclusiones: El diagnóstico de esta infección es difícil y se presenta habitualmente en pacientes trasplantados renales. Sin embargo, la asociación de esta infección con este tipo de pacientes no ha sido aún explicada

Alpha-syntrophin dependent expression of tubulin alpha 8 protein in hepatocytes

The scaffold protein alpha-syntrophin (SNTA) is a component of the dystrophin glycoprotein complex and has been comprehensively studied in skeletal muscle and adipocytes. SNTA is further expressed in the liver where its biological role remains unclear. Unpublished data from our group suggested that SNTA deficiency is associated with altered tubulin alpha 8 (TUBA8) levels in fat. TUBA8 is highly expressed in different cell lines including hepatoma cells, and here we analyzed whether SNTA has a role herein. In Hepa1-6 cells, TUBA8 protein levels were increased upon SNTA knock down and were reduced upon overexpression of SNTA. This regulation was not identified when analyzing mRNA expression. In the liver of SNTA-deficient mice, TUBA8 protein was higher compared to the respective wild-type controls while RNA expression was even suppressed. Using the HaloTag platform, TUBA8 was found to form a complex with SNTA in Hepa1-6 cells. In the hepatic stellate cell line LX-2, the lack or overexpression of SNTA did, however, not change TUBA8 protein expression. SNTA and TUBA8 are described to regulate cell proliferation. Yet, knock down of SNTA did neither affect proliferation nor viability of Hepa1-6 cells. The present study shows that SNTA protein levels are inversely related to TUBA8 protein expression in the hepatocyte cell line Hepa1-6

Transdiferenciación neuronal de células madre mesenquimales de médula ósea humana / Neuronal transdifferentiation of human bone marrow mesenchymal stem cells

En el presente estudio se muestra la posibilidad de lograruna transdiferenciación de células madre mesenquimales humanas,obtenidas del estroma de médula ósea, hacia neuronasadultas. Los resultados obtenidos confirman experiencias previasacerca de que las células madre del estroma de la médulaósea experimentan cambios fenotípicos y expresan marcadoresde diferenciación neuronal cuando se cultivan in vitrocon determinadas sustancias químicas. Por otra parte, el presenteestudio demuestra que la transdiferenciación neuronalde estas células puede ser obtenida también por medio de unco-cultivo con células de Schwann. La transdiferenciación enco-cultivo comienza más tardíamente, y aunque la expresiónde nestina, como primer marcador neural, se observa ya a las4 horas del co-cultivo, esta expresión disminuye entre las 24 y72 horas, momento en que comienzan a observarse células conexpresión de marcadores de diferenciación neuronal, aumentandoprogresivamente el número de células que expresanEnolasa específica neuronal, Proteína de neurofilamentos yBeta-tubulina

This study describes the possibility to obtain neuronaltransdifferentiation of human mesenchymal stem cells, obtainedfrom the bone marrow stroma. Our present resultsconfirm previous experiences showing that these cells expressmarkers of neuronal differentiation when they arecultured with certain chemical factors. On the other hand,the present study demonstrates that a neuronal transdifferentiationof these cells can also be obtained by means of aco-culture with Schwann cells. In co-culture, transdifferentiationbegins later, although nestin expression is first observed4 hours after beginning the co-culture, it decreasedbetween 24 and 72 hours, and at this time, a clear increasein the number of NSE, NF and beta-tubulin-positive cells,can be seen