Factores (conocimientos, riesgos y prevención) asociados a los accidentes laborales en los trabajadores del hospital de especialidades del IHSS, Tegucigalpa municipio Distrito Central, Honduras, 2009

Estudio descriptivo y analítico. Se encontró que entre más alto es el nivel académico, menos accidente laboral se reporta y entre menos nivel académico más accidente laboral es reportado. Entre los accidentes se encontró: caídas, pincharse con agujas y derrame de secreciones corporales. Se recomienda al IHSS acompañar a los gerentes y jefes del hospital de especialidades en acciones para prevenir accidentes en el ambiente de trabajo; al Ministerio del Trabajo: monitorear y supervisar las instituciones prestadoras de servicios de salud e involucrar al personal responsable de estos procesos en todas las actualizaciones relacionada

Indirect RKKY-Type Interaction by Direct Oxygen Hopping

The three-band Emery model, describing the holes in the CuO$\text{}_{2}$ planes of the high-temperature superconducting oxides, is considered. The model includes the direct oxygen-oxygen hopping integral t$\text{}_{pp}$. The exact Bogolyubov transformation is used to exclude one oxygen band and obtain a two-dimensional Anderson model. Afterward, the effective Hamiltonian is obtained by eliminating the second oxygen band with the use of two approximate canonical transformations. The effective Hamiltonian describes the spins residing on the copper sites and interacting through an indirect interaction J$\text{}_{SX}$(R), where R is the distance between two copper ions. J$\text{}_{SX}$(R) depends on the doping rate δ and is a decaying function of R. Numerical results for J$\text{}_{SX}$(R) are given for different doping rates δ for the case of parabolic bands. The obtained interaction J$\text{}_{SX}$(R), when added to the original antiferromagnetic interaction (present in oxides at δ = 0), might lead to a frustration of the long-range antiferromagnetic ordering upon doping

Immunophenotypic features of dedifferentiated skull base chordoma: An insight into the intratumoural heterogeneity

Chordomas are rare and low-grade malignant solid tumours, despite their histologically benign appearance, that arise in the bone from embryonic notochordal vestiges of the axial skeleton, a mesoderm-derived structure that is involved in the process of neurulation and embryonic development. Chordomas occurring in the skull base tend to arise in the basiocciput along the clivus. Three major morphological variants have been described (classical, chondroid, and atypical/dedifferentiated). The pathogenesis and molecular mechanisms involved in chordoma development remain uncertain. From a pathological standpoint, the microenvironment of a chordoma is heterogeneous, showing a dual epithelial-mesenchymal differentiation. These tumours are characterised by slow modality of biologic growth, local recurrence, low incidence of metastasis rates, and cancer stem cell (CSC) phenotype. The main molecular findings are connected with brachyury immunoexpression and activation of the downstream Akt and mTOR signalling pathways. The differentiation between typical and atypical chordomas is relevant because the tumoural microenvironment and prognosis are partially different. This review provides an insight into the recent and relevant concepts and histochemical markers expressed in chordomas, with special emphasis on dedifferentiated chordomas and their prognostic implications

Coumarins from the roots of Prangos uloptera

Three new coumarins, 6-O-[β-d-apiofuranosyl-(1 → 6)-β-d-glucopyranosyl]-prenyletin, 3″-O-[β-d-apiofuranosyl-(1 → 6)-β-d-glucopyranosyl]-oxypeucedanin hydrate and 2″-O-[β-d-apiofuranosyl-(1 → 6)-β-d-glucopyranosyl]-oxypeucedanin hydrate, together with six known coumarins, 3″-O-[β-d-apiofuranosyl-(1 → 6)-β-d-glucopyranosyl]-heraclenol, 3″-O-(β-d-glucopyranosyl)-heraclenol, tortuoside, 3″-O-(β-d-glucopyranosyl)-oxypeucedanin hydrate, heraclenol and oxypeucedanin hydrate, have been isolated from the roots of Prangos uloptera, and the structures of these coumarins were unequivocally determined by spectroscopic means, notably UV, HRESIMS, and 1D and 2D NMR spectroscopy