RESUMEN
A 3D tellurium-substituted heteropolyoxoniobate framework H5K3Na[Cu(en)2]2[Cu(en)0.75(H2O)2.5]{[(Te2Nb19O58)(µ3-OH)2]}·24H2O (1, en = ethylenediamine) with a 6-connected pcu topology is built from heart-shaped {Te2Nb19O60} clusters and copper complexes. The {Te2Nb19O60} cluster represents the new tellurniobate structure type with a 19-nuclearity Nb cluster. It consists of two new monovacant Lindqvist {Nb5O19} clusters, one boat-shaped {Nb9O32} cluster and two TeO32- anions. The {Te2Nb19O60} polyanions are interlinked by [Cu(en)2]2+ complexes into a 2D (4, 4) grid-like layer containing rhombic sheets. The Cu2+ supports the adjacent layers through Te-O-Cu-O-Te- bonds to form a three-dimensional heteropolyoxoniobate framework with 1D channels. This compound exhibits good chemical and solvent stability and proton conductivity, with a conductivity of 7.9 × 10-3 S cm-1 at 85 °C under 98% RH.
RESUMEN
The aim of the present study was to observe the effects of geneactivated matrix (GAM) on autograft healing of the anterior cruciate ligament. Fortyeight rabbits were randomly divided into groups A and B. Rabbits were used to construct models of anterior cruciate ligament reconstruction. In group A, transforming growth factor (TGF)ß1 was locally injected into the bone tunnel, while in group B, empty vector was administered. Tendons were removed to observe histology and ultrastructure and to evaluate biomechanics at postoperative months 1, 3 and 6. Optical microscopy revealed increased numbers of fibroblasts and collagen fibers in group A at each timepoint compared with B. Electron microscopy identified increased mitosis and abundance of fibroblasts, endoplasmic reticulum and mitochondria in group A at each timepoint compared with B. No significant difference was identified in the biomechanical parameters between the 2 groups at postoperative month 1. At postoperative months 3 and 6, maximum force and elastic modulus were greater in group A compared with group B (P<0.0.5). No significant differences in other biochemical parameters were observed at these timepoints. The healing ligament graft transfected with TGFß1 by GAM was observed to have improved tissue structure and biomechanical characteristics. The results of the current study may provide a theoretical basis for GAM application in ligament repair.