The use of an acellular matrix derived from human dermis for the treatment of full-thickness skin wounds.

Full-thickness skin wounds occur in many different clinical cases and the use of biological acellular dermal matrices (ADMs) to reconstruct the damaged area is increasing in the field of plastic and reconstructive surgery. In particular, the ability of ADMs to maintain the structural properties of extracellular matrix as well as to provide a suitable environment for cell growth makes their use suitable for the improvement of wound healing and the reduction of side effects deriving from contracture and scar tissue formation. In this study, we describe the clinical use of a recently developed human dermal matrix (HDM) in combination with graft skin as an alternative reconstructive solution for the treatment of full-thickness skin wounds. The HDM was applied in combination with autologous graft skin on three different clinical cases in which full-thickness skin wounds occurred. The clinical outcomes were evaluated in the patients during their follow-up. Histological as well as ultra-structural analysis were also performed on skin biopsy of the clinical case 3 one year after the treatment with HDM. The use of HDM stimulates the wound healing process in all clinical cases of full-thickness skin wounds here described with a functional and aesthetic rescue of the damaged area. Histological and ultra-structural analysis show a regenerative healing of the wound area with well-organized/oriented connective tissue in which cellular infiltration as well as blood vessels are evident. Our results support the clinical use of HDM as a permanent dermal replacement for the treatment of full-thickness skin wounds.

Histological and ultrastructural evaluation of human decellularized matrix as a hernia repair device.

Recently, interest has been increasing for human decellularized matrices, due to their ability to reduce numerous side effects related to hernia repair. To date, only animal studies investigated the biological interaction post-implant of human decellularized matrices for soft tissue repair. Therefore, the aim of this study was to evaluate the morphological response one year post implant of human decellularized matrix, through morphological analysis of human biopsies. The histological and ultrastructural results revealed a perfect cellular repopulation and neoangiogenesis, with minimal inflammatory response and a well-organized collagen matrix. The results have indicated that this scaffold can be an effective treatment for hernia.

The development of a decellularized extracellular matrix-based biomaterial scaffold derived from human foreskin for the purpose of foreskin reconstruction in circumcised males.

The circumcision of males is emphatically linked to numerous sexual dysfunctions. Many of the purported benefits do not hold up to the scrutiny of extensive literature surveys. Involuntary circumcision, particularly when not medically warranted, is also associated with many psychological and emotional traumas. Current methods to reconstruct the ablated tissue have significant drawbacks and produce a simple substitute that merely imitates the natural foreskin. Extracellular matrix-based scaffolds have been shown to be highly effective in the repair and regeneration of soft tissues; however, due to the unique nature of the foreskin tissue, commercially available biomaterial scaffolds would yield poor results. Therefore, this study discusses the development and evaluation of a tissue engineering scaffold derived from decellularized human foreskin extracellular matrix for foreskin reconstruction. A chemicophysical decellularization method was applied to human foreskin samples, sourced from consenting adult donors. The resulting foreskin dermal matrices were analyzed for their suitability for tissue engineering purposes, by biological, histological, and mechanical assessment; fresh frozen foreskin was used as a negative control. Sterility of samples at all stages was ensured by microbiological analysis. MTT assay was used to evaluate the absence of viable cells, and histological analysis was used to confirm the maintenance of the extracellular matrix structure and presence/integrity of collagen fibers. Bioactivity was determined by submitting tissue extracts to enzyme-linked immunosorbent assay and quantifying basic fibroblast growth factor content. Mechanical properties of the samples were determined using tensile stress tests. Results found foreskin dermal matrices were devoid of viable cells (p < 0.0001) and the matrix of foreskin dermal matrices was maintained. Basic fibroblast growth factor content doubled within after decellularization (p < 0.0001). Tensile stress tests found no statistically significant differences in the mechanical properties (p < 0.05). These results indicate that the derived foreskin dermal matrix may be suitable in a regenerative approach in the reconstruction of the human foreskin.

Glomerular lesions in dogs infected with Leishmania organisms.

OBJECTIVE: To histologically identify glomerular lesions in dogs infected with Leishmania organisms. ANIMALS: 41 dogs (17 sexually intact males and 14 sexually intact and 10 ovariohysterectomized females) that had positive results when tested for leishmaniosis as determined by use of serologic evaluation (indirect fluorescent antibody test, titers of 1:80 to 1:640) and direct microscopic identification of the protozoal organisms. PROCEDURE: Urine samples were collected by use of cystocentesis and examined by qualitative SDS-agarose gel electrophoresis (AGE). All dogs had non-selective (glomerular) or mixed (glomerular and tubular) proteinemia. Specimens were obtained from each dog during ultrasound-assisted renal biopsy and used for histologic examination. Each specimen was stained with H&E, periodic acid-Schiff, Goldner's trichrome, methenamine silver, and Congo Red stains. Specimens were adequate for evaluation when they contained at least 5 glomeruli/section, except for specimens stained with Congo Red in which 1 glomerulus/section was adequate. RESULTS: Examination of renal biopsy specimens revealed various glomerular lesions in all dogs and interstitial or tubular (or both) lesions in 23 of 41 (55%) dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Glomerular lesions that develop in dogs during infection with Leishmania organisms can be classified histologically as mesangial glomerulonephritis, membranous glomerulonephritis, membranoproliferative glomerulonephritis, and focal segmental glomerulonephritis. Tubulointerstitial histopathologic conditions were not observed as the primary lesion, despite being evident in 23 of 41 (55%) dogs. Use of SDS-AGE for qualitative evaluation of proteinuria and successive collection of specimens during renal biopsies following diagnosis of nonselective glomerular proteinuria provides the possibility for early identification of renal lesions.

Expression of 19 microRNAs in glioblastoma and comparison with other brain neoplasia of grades I-III.

Several biomarkers have been proposed as useful parameters to better specify the prognosis or to delineate new target therapy strategies for glioblastoma patients. MicroRNAs could represent putative target molecules, considering their role in tumorigenesis, cancer progression and their specific tissue expression. Although several studies have tried to identify microRNA signature for glioblastoma, a microRNA profile is still far from being well-defined. In this work the expression of 19 microRNAs (miR-7, miR-9, miR-9∗, miR-10a, miR-10b, miR-17, miR-20a, miR-21, miR-26a, miR-27a, miR-31, miR-34a, miR-101, miR-137, miR-182, miR-221, miR-222, miR-330, miR-519d) was evaluated in sixty formalin-fixed and paraffin-embedded glioblastoma samples using a locked nucleic acid real-time PCR. Moreover, a comparison of miRNA expressions was performed between primary brain neoplasias of different grades (grades IV-I). The analysis of 14 validated miRNA expression in the 60 glioblastomas, using three different non-neoplastic references as controls, revealed a putative miRNA signature: mir-10b and miR-21 were up-regulated, while miR-7, miR-31, miR-101, miR-137, miR-222 and miR-330 were down-regulated in glioblastomas. Comparing miRNA expression between glioblastoma group and gliomas of grades I-III, 3 miRNAs (miR-10b, mir-34a and miR-101) showed different regulation statuses between high-grade and low-grade tumors. miR-10b was up-regulated in high grade and significantly down-regulated in low-grade gliomas, suggesting that could be a candidate for a GBM target therapy. This study provides further data for the identification of a miRNA profile for glioblastoma and suggests that different-grade neoplasia could be characterized by different expression of specific miRNAs.

Solitary fibrous tumor of the spinal nerve rootlet: report of a case mimicking schwannoma.

We report a case of solitary fibrous tumor involving the spinal nerve root at the L1-L2 level in a 67-year-old man. The patient presented with lumbar pain and weakness in his right lower extremity. Histologically, the tumor was composed of a proliferation of monomorphous spindle cells in an abundant collagenous stroma; neither necrosis nor mitoses were evident. These cells were strongly immunoreactive with CD34, Bcl-2, CD99, and vimentin, but were negative with S100 protein, smooth muscle actin, and epithelial membrane antigen. Such an immunohistochemical profile was consistent with a solitary fibrous tumor of the spinal nerve rootlet and ruled out the main differential diagnoses, schwannoma and meningioma. The present case suggests that solitary fibrous tumor should be considered in differentiating spindle cell lesions of the spinal cord and nerve rootlet.