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Objective: To evaluate the effects of VEGF, BMP-7, Matrigel(TM), hyaluronic acid, in vitro cultured chondrocytes and trephination to promote and enhance the healing process of avascular meniscal tears in an animal model., Methods: A longitudinal tear was produced in the inner avascular part of the meniscus of 24 sheeps. Each tear was treated with trephination technique and suture. The animals were divided into 6 groups to receive a different treatment: control (I); VEGF, BMP-7, Matrigel(TM), hyaluronic acid, in vitro cultured chondrocytes. At 8 weeks from surgery, meniscal samples were explanted and analyzed by histology, immunohistochemistry, and histomorphometry., Results: At the histological examination, Group IV and VI showed a partial closure of the meniscal lesion, whereas Group I, II, III, and V did not show any evidence of healing. In the group IV, the healed tissue represented the 22.95% of the lesion area. In the group VI, the healed tissue represented the 43.75% of the lesion area., Conclusions: Autologous chondrocytes and BMP-7 associated with trephination and suture techniques enhanced healing process of meniscal tears in the avascular inner third of the meniscus in ovine model.

Background: In Alport syndrome (AS) impaired production and/or assembly of col IV alpha-chain isoforms results in abnormal structure of glomerular basement membrane (GBM), haematuria and, frequently, progressive renal disease. We investigated the relationship between col IV alpha-chains expression and morphology of GBM, as a possible key to the better understanding of the pathogenesis of renal disease in AS., Methods: GBM distribution of col IV alpha1-, alpha3-, and alpha5-chain was investigated by immunohistochemistry in 32 patients (21 males and 11 females, mean age at biopsy of 11.5 years) with ultrastructural findings suggestive of AS. Ten patients had a proven COL4A5 mutation. Based on the severity of ultrastructural findings, the biopsies were grouped in three (I-III) electron microscopy (EM) classes. Significant EM changes of GBM (thinning, thickening, splitting, basket weaving of the lamina densa) were singularly evaluated using a semiquantitative scale (0-3)., Results: Col IV alpha1-chain was demonstrated in GBM of all patients. Three patterns of staining for col IValpha3- and alpha5-chains were observed: positive, negative, and alpha3(IV)-positive/alpha5(IV)-negative. By chi(2)-test, EM class III lesions and complete loss of alpha3(IV)- and alpha5(IV)-antigen were significantly more frequent (P<0.05 and P<0.01) in male patients, but no significant relation was observed between EM classes and immunohistochemical patterns. GBM alterations did not correlate with staining for alpha5(IV)-chain. Intensity of alpha3(IV)-chain staining, however, had a negative correlation (P<0.05) with the severity of GBM basket weaving., Conclusions: Our results suggest that the alpha3(IV)-chain-containing col IV-network plays a fundamental role in structural and, possibly, functional organization of GBM. Absence of alpha3(IV)-chain in GBM could indicate a more severe renal disease in AS.

A total of 108 patients affected by Alport's syndrome, taken from 97 families, were enrolled in a genetic and ultrastructural study. Sixty-four families (75 patients) were X-linked, seven autosomal recessive, two autosomal dominant, five uninterpretable, and 19 sporadic. The ultrastructural features were consistent with Alport's syndrome in 66, doubtful in 20, and not significant for Alport's syndrome in 22 patients in the X-linked, sporadic, and genetically uninterpretable groups (without significant differences), as well as in the autosomal group. Mutations of the COL4A5 gene were present in 36 patients in the first three groups, without significant differences. More severe mutations were more frequently present in patients with an ultrastructural pattern consistent with Alport's syndrome. Nevertheless, there seems to be no strict correlation between mutation and ultrastructure, because a major rearrangement was found in a patient with no significant lesions, and different morphologic patterns were detected in patients Belonging to the same family. Immunohistochemical investigation into 24 patients for alpha (IV) chains showed that both alpha 3(IV) and alpha 5(IV) were lacking in the glomerular basement membrane of 13 patients (five with mutations) and were expressed in another six (three with mutations and one in the autosomal group). On the contrary, in this study the retained expression of alpha 3(IV) chain was found, despite the lack of alpha 5(IV) in the glomerular basement membrane of five patients (two with mutation). These different patterns could be related to both the type and severity of the COL4A5 mutations. All of the ultrastructural patterns were identified in all three immunohistochemical groups. Ultrastructural features and alpha 5(IV) chain production, even if an expression of a genetic mutation, do not strictly correlate. The combined use of analysis of collagen expression and electron microscopy made it possible to diagnose Alport's syndrome in 92% of the cohort, and therefore this approach is advisable. A multidisciplinary approach is recommended in the study of Alport's syndrome in an attempt to achieve a better diagnostic definition of and insight into the pathogenetic mechanisms.

Absent or defective collagen VII at the dermo-epidermal junction is the hallmark of dystrophic recessive epidermolysis bullosa. Little is known of the alterations of other collagenous and non-collagenous components of the basement membrane; it is likely that their assembly may be disturbed by the lack of collagen VII molecules. The spatial relationship of collagen IV and laminin has been studied, both in bullous and in non-bullous areas. Skin biopsies from five patients affected by severe dystrophic recessive epidermolysis bullosa were rapidly frozen and freeze-dried. Collagen IV and laminin were labelled with specific monoclonal antibodies and FITC- or TRITC-conjugated secondary antibodies. Sections were observed with conventional light/fluorescence microscopy and with confocal laser scanning microscopy. Collagen IV and laminin were not co-localized: the former displayed a split image, being present at the floor and the roof of the blister, while the latter was confined to the roof. Confocal microscopy also allowed three-dimensional (3D) reconstruction of the dermo-epidermal junction from a series of optical sections, with viewing of the reconstructed specimen from a sequence of angles. By this procedure, laminin exhibits an irregular, coarsely granular distribution, both in affected and in apparently non-affected areas, while collagen IV appears as a homogeneous sheet. These results show that freeze-drying is the technique of choice for high-resolution immunofluorescence of skin samples and suggest that in dystrophic recessive epidermolysis bullosa, a complex disruption of the extracellular matrix assembly exists even before blister formation, probably due to the lack of collagen VII.