Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 7 de 7
Filter
1.
Int J Mol Sci ; 22(1)2021 Jan 05.
Article in English | MEDLINE | ID: mdl-33466246

ABSTRACT

Temporomandibular joint osteoarthritis (TMJ-OA) is a chronic degenerative disease that is often characterized by progressive impairment of the temporomandibular functional unit. The aim of this randomized controlled animal trial was a comparative analysis regarding the chondroregenerative potency of intra-articular stem/stromal cell therapy. Four weeks after combined mechanical and biochemical osteoarthritis induction in 28 rabbits, therapy was initiated by a single intra-articular injection, randomized into the following groups: Group 1: AB Serum (ABS); Group 2: Hyaluronic acid (HA); Group 3: Mesenchymal stromal cells (STx.); Group 4: Mesenchymal stromal cells in hyaluronic acid (HA + STx.). After another 4 weeks, the animals were euthanized, followed by histological examination of the removed joints. The histological analysis showed a significant increase in cartilage thickness in the stromal cell treated groups (HA + STx. vs. ABS, p = 0.028; HA + ST.x vs. HA, p = 0.042; STx. vs. ABS, p = 0.036). Scanning electron microscopy detected a similar heterogeneity of mineralization and tissue porosity in the subchondral zone in all groups. The single intra-articular injection of a stem cell containing, GMP-compliant advanced therapy medicinal product for the treatment of iatrogen induced osteoarthritis of the temporomandibular joint shows a chondroregenerative effect.


Subject(s)
Osteoarthritis , Regeneration , Stem Cells , Temporomandibular Joint Disorders , Temporomandibular Joint , Animals , Female , Male , Rabbits , Cartilage, Articular/metabolism , Cartilage, Articular/pathology , Hyaluronic Acid/metabolism , Injections, Intra-Articular/methods , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Osteoarthritis/metabolism , Osteoarthritis/pathology , Regeneration/physiology , Stem Cells/cytology , Stem Cells/metabolism , Temporomandibular Joint/metabolism , Temporomandibular Joint/pathology , Temporomandibular Joint Disorders/metabolism , Temporomandibular Joint Disorders/pathology
2.
Int J Mol Sci ; 21(19)2020 Sep 26.
Article in English | MEDLINE | ID: mdl-32993100

ABSTRACT

For the post-surgical treatment of oral wounds and mucosal defects beyond a certain size, the gold standard is still an autologous skin or mucosal graft in combination with complex suturing techniques. A variety of techniques and biomaterials has been developed for sutureless wound closure including different tissue glues or collagen patches. However, no wound covering that enables for sutureless fixation has yet been introduced. Thus, a new system was developed that allows for sutureless wound covering including a transparent collagen membrane, which can be attached to the mucosa using a specially modified 2λ laser beam with integrated temperature sensors and serum albumin as bio-adhesive. The sutureless wound closure system was tested for its applicability and its cytocompatibility by an established in vitro model in the present study. The feasibility of the laser system was tested ex vivo on a porcine palate. The in vitro cytocompatibility tests excluded the potential release of toxic substances from the laser-irradiated collagen membrane and the bio-adhesive. The results of the ex vivo feasibility study using a porcine palate revealed satisfactory mean tensile strength of 1.2-1.5 N for the bonding of the membrane to the tissue fixed with laser of 980 nm. The results suggest that our newly developed laser-assisted wound closure system is a feasible approach and could be a first step on the way towards a laser based sutureless clinical application in tissue repair and oral surgery.


Subject(s)
Biocompatible Materials/therapeutic use , Collagen/therapeutic use , Laser Therapy/methods , Wound Healing , Animals , Cattle , Cell Line , Cell Proliferation , Cell Survival , Equipment Design , Feasibility Studies , Laser Therapy/instrumentation , Membranes, Artificial , Mice , Swine , Temperature
3.
Bioimpacts ; 9(3): 161-172, 2019.
Article in English | MEDLINE | ID: mdl-31508331

ABSTRACT

Introduction: Mesenchymal stromal/stem cells (MSCs) derived from fat tissue are an encouraging tool for regenerative medicine. They share properties similar to the bone marrow-derived MSCs, but the amount of MSCs per gram of fat tissue is 500x higher. The fat tissue can easily be digested by collagenase, releasing a heterogeneous cell fraction called stromal vascular fraction (SVF) which contains a variable amount of stromal/stem cells. In Europe, cell products like the SVF derived from fat tissue are considered advanced therapy medicinal product (ATMPs). As a consequence, the manufacturing process has to be approved via GMP-compliant process validation. The problem of the process validation for SVF is the heterogeneity of this fraction. Methods: Here, we modified existing purification strategies by adding an additional plastic adherence incubation of maximal 20 hours after SVF isolation. The resulting cell fraction was characterized and compared to SVF as well as cultivated adipose-derived stromal/stem cells (ASCs) with respect to viability and cell yield, the expression of surface markers, differentiation potential and cytokine expression. Results: Short-term incubation significantly reduced the heterogeneity of the resulting cell fraction compared to SVF. The cells were able to differentiate into adipocytes, chondrocytes, and osteoblasts. More importantly, they expressed trophic proteins which have been previously associated with the beneficial effects of MSCs. Furthermore, GMP compliance of the production process described herein was acknowledged by the national regulatory agencies (DE_BB_01_GMP_2017_1018). Conclusion: Addition of a short purification-step after the SVF isolation is a cheap and fast strategy to isolate a homogeneous uncultivated GMP-compliant cell fraction of ASCs.

4.
Biomed Res Int ; 2015: 120903, 2015.
Article in English | MEDLINE | ID: mdl-26345612

ABSTRACT

PURPOSE: The purpose of the study was to evaluate the influence of a continued antiplatelet therapy with clopidogrel on postoperative bleeding risk in patients undergoing skin tumor resection and reconstruction with local flaps or skin grafts under outpatient conditions. PATIENTS AND METHODS: The authors designed and implemented a retrospective clinical cohort study at the General Hospital Balingen. The primary endpoint was the bleeding ratio in patients with clopidogrel treatment in comparison to patients without any anticoagulant or antiplatelet therapy. Wound healing was evaluated on days 1, 3, 5, 7, 10, and 14. RESULTS: 650 procedures were performed, 123 of them under continued clopidogrel therapy. There were significantly more postoperative bleeding complications among patients with continued antiplatelet therapy. Regarding the whole study population, malignant lesions, a larger defect size, and skin grafts were accompanied by a higher rate of bleeding incidents. However, there were no significant findings in the univariate analysis of the clopidogrel group. All bleeding incidents were easily manageable. CONCLUSION: Despite an increased bleeding ratio among patients under continued clopidogrel therapy, the performance of simple surgical procedures can be recommended. However, cautious preparation and careful hemostasis are indispensable.


Subject(s)
Postoperative Hemorrhage/chemically induced , Postoperative Hemorrhage/epidemiology , Surgical Flaps , Ticlopidine/analogs & derivatives , Aged , Clopidogrel , Female , Humans , Male , Middle Aged , Risk Factors , Ticlopidine/administration & dosage , Ticlopidine/adverse effects , Wound Healing/drug effects
5.
J Magn Reson Imaging ; 41(1): 110-6, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24357078

ABSTRACT

PURPOSE: To calculate regional fetal brain oxygen saturation (sO2) during hypoxia in sheep. MATERIALS AND METHODS: Eight pregnant ewes were examined at a 3T MR-scanner using blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI) to measure signal intensity changes of the fetal brain during a control period and a period of induced hypoxia. Regions of interest were placed in the fetal cerebrum to assess ΔR2* from GRE signal intensity plateaus (S(control), S(hypoxia)) and the relation between ΔR2* and ΔpO2 was analyzed. A probe was placed surgically in the fetal brain to directly measure local pO2 as a reference standard. Baseline and hypoxic pO2 values were recorded and compared (ΔpO2). RESULTS: Mean fetal brain pO2 decreased from 14.3 mmHg (95% confidence interval [CI]: 10-19) to 3.4 mmHg (95% CI: 2-5) during hypoxia (mean ΔpO2 = 10.9 mmHg and ΔR2* = -5s(-1)). A significant correlation between ΔR2* and ΔpO2 was noted (r = 0.93, P < 0.001), and conversion of pO2 into sO2 resulted in a linear regression coefficient of (-0.14 ± 0.01)s(-1)/% (r(2) = 0.91). CONCLUSION: Measured fetal brain BOLD-MRI was compared and converted to pO2, followed by calculation of cerebral sO2.


Subject(s)
Brain/pathology , Fetal Hypoxia/pathology , Magnetic Resonance Imaging/methods , Animals , Female , Fetus , Pregnancy
6.
Biomed Res Int ; 2014: 907272, 2014.
Article in English | MEDLINE | ID: mdl-25009821

ABSTRACT

UNLABELLED: INTRODUCTION; Face transplantation (FT) is an innovative achievement of modern reconstructive surgery and is on the verge of becoming a common surgical opportunity. This review article was compiled to provide an update on this surgical field, especially regarding clinical outcomes, benefits, and complications implied. METHODS: We performed an extensive research on all English-language Medline articles, case reports, and reviews published online until September 15, 2013. Used search terms were "face transplantation," "face transplant," "facial transplantation," "facial transplant," "face allograft," and "facial allograft." RESULTS: To date 27 FTs have been performed worldwide. 19 of these cases have been published in the Medline database. Long-term follow-up reports of FT cases are rare. Three deaths associated with the procedure have occurred to date. The clinical outcomes of FT are satisfying. Reinnervation of sensation has been faster than motor recovery. Extensive functional improvements have been observed. Due to strict immunosuppression protocols, no case of hyperacute or chronic rejection and no graft-versus-host disease have occurred to date. CONCLUSIONS: As studies on long-term outcomes are missing, particularly regarding immunosuppression-related complications, FT will stay experimental for the next years. Nevertheless, for a small group of patients, FT already is a feasible reconstructive option.


Subject(s)
Facial Transplantation/methods , Immunosuppression Therapy/methods , Allografts , Humans , MEDLINE
7.
J Thorac Oncol ; 8(3): 279-86, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23399959

ABSTRACT

INTRODUCTION: Homologous recombination repair (HRR) is a critical pathway for the repair of DNA damage caused by cisplatin or poly-ADP ribose polymerase (PARP) inhibitors. HRR may be impaired by multiple mechanisms in cancer, which complicates assessing the functional HRR status in cells. Here, we monitored the ability of non-small-cell lung cancer (NSCLC) cells to form subnuclear foci of DNA repair proteins as a surrogate of HRR proficiency. METHODS: We assessed clonogenic survival of 16 NSCLC cell lines in response to cisplatin, mitomycin C (MMC), and the PARP inhibitor olaparib. Thirteen tumor explants from patients with NSCLC were subjected to cisplatin ex vivo. Cells were assayed for foci of repair-associated proteins such as BRCA1, FANCD2, RAD51, and γ-H2AX. RESULTS: Four cell lines (25%) showed an impaired RAD51 foci-forming ability in response to cisplatin. Impaired foci formation correlated with cellular sensitivity to cisplatin, MMC and olaparib. Foci responses complemented or superseded genomic information suggesting alterations in the ATM/ATR and FA/BRCA pathways. Because baseline foci in untreated cells did not predict drug sensitivity, we adapted an ex vivo biomarker assay to monitor damage-induced RAD51 foci in NSCLC explants from patients. Ex vivo cisplatin treatment of explants identified two tumors (15%) exhibiting compromised RAD51 foci induction. CONCLUSIONS: A fraction of NSCLC harbors HRR defects that may sensitize the affected tumors to DNA-damaging agents including PARP inhibitors. We propose that foci-based functional biomarker assays represent a powerful tool for prospective determination of treatment sensitivity, but will require ex vivo techniques for induction of DNA damage to unmask the underlying HRR defect.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Non-Small-Cell Lung/genetics , Lung Neoplasms/genetics , Poly(ADP-ribose) Polymerase Inhibitors , Recombination, Genetic/genetics , Recombinational DNA Repair/genetics , Antibiotics, Antineoplastic/pharmacology , BRCA1 Protein/metabolism , Carcinoma, Non-Small-Cell Lung/diagnosis , Carcinoma, Non-Small-Cell Lung/drug therapy , Cisplatin/pharmacology , DNA Damage/drug effects , DNA Damage/genetics , Fanconi Anemia Complementation Group D2 Protein/metabolism , Humans , Immunoenzyme Techniques , Lung Neoplasms/diagnosis , Lung Neoplasms/drug therapy , Microscopy, Fluorescence , Mitomycin/pharmacology , Phthalazines/pharmacology , Piperazines/pharmacology , Poly (ADP-Ribose) Polymerase-1 , Rad51 Recombinase/metabolism , Recombinational DNA Repair/drug effects , Tumor Cells, Cultured , Tumor Stem Cell Assay
SELECTION OF CITATIONS
SEARCH DETAIL
...