No abstract

Reconstruction of large size maxillofacial bone defects following trauma or tumor resection still represents a challenging task for surgeons. Various types of bone materials are used as the grafts for the reconstruction of bone defect: auto, allo, xeno and alloplastic bones. In recent years, using the methods of decellularization has enabled to obtain the natural,biocompatible threedimensional xenograft for the reconstruction of bone defects. Removing DNA from the bone matrix is critical because this DNA may stimulate immune reactions by activating cytokine production and B-cell immunoglobulin secretion after transplantation. For the large maxillofacial bone reconstruction procedures, the decellularized bovine bone graft has proven to be effective, easy to handle and biocompatible, providing excellent final aesthetic and functional results. However, more animal and clinical studies are required to further assess the osteogenic activity and integration of decellularized bone grafts with the native bone.

BackgroundRecent studies have demonstrated mesenchymal stem cell migration toward tumor locations. When applied locally, MSCs interact with the locally residing host cells. The mechanisms behind this are still unclear. We aimed to detect the possible action mechanisms of MSCs on the in vivo growth of primary human oral squamous cell carcinoma.MethodsIn mouse model of OSSC, chemotherapy with Cisplatin was done beginning from 9 day of tumor visualization. 3 weeks after tumor cell injection cultivated MSCs were administrated in tail vein or directly intra‐tumorally. Animals underwent surveillance and afterward were sacrificed. Tumor growth was measured. MSCs biodistribution was assessed with bioluminescent analysis. Tumor tissues were tested morphologically and immunohistochemically for angiogenesis, hypoxia status, and cell apoptosis.ResultsIn the group treated with Cisplatin in combination with mesenchymal stem cell injection, the average size of the tumor was 98.9 ± 7.65 mm3. In the experimental group, tumor tissues were less outlined and the presence of necrotic areas and connective tissue basal layers was detected. Immunohistochemical surveys with CD31 and anti‐carbonic anhydrase 9 demonstrated strongly developed micro‐vessel structures and small isles of hypoxia in the tumor tissues. TUNEL assay revealed in the same group that tumor tissues were mostly comprised of apoptotic cells. Viable cell communities presented as small isles.ConclusionThe study demonstrates that intra‐tumorally injected MSCs, combined with Cisplatin, leads to a minimal hypoxia status and increased apoptotic activity in tumor tissues, compared with the control group. This finding can be explained with better distribution of Cisplatin due to increased angiogenesis.

The laser-induced fluorescence (LIF) spectra have been measured for cancer-infused and control mice mucosa tissues. It was established that there is quite a difference between their LIF spectral shapes. These spectral shapes are used to express the diagnostic of different states of tissues: from normal to cancer.

Introduction:Diabetes is predicted to be the major killer of population all across the world with likelihood of 366 million people suffering from diabetes by the year 2030. Strategies to curb this problem are being established in the form of pancreatic transplantation or islet cell replacement from adult and embryonic stem cells producing insulin. We present prospective study of glucose-sensitive insulin-secreting mesenchymal stem cells (IS-MSC) generated from human adipose tissue (h-AD) sans xenogenic material. Methods: After Institutional Review Board approval and informed consent forms from voluntary human donors ten grams anterior abdominal wall h-AD was collected in proliferation medium composed of α-Minimum Essential Media, albumin, Fibroblast-growth factor and antibiotics; minced, incubated in collagenase-I at 37°C with shaker and centrifuged. Supernatant and pellets were separately cultured in proliferation medium on cell+ plates at 37°C with 5% CO2 for 10 days. Cells were harvested, checked for viability, sterility, counts, flow-cytometry (CD45 -/90 + /73 + ) and differentiated into insulin-expressing cells using differentiation medium composed of Dulbecco's modified eagle's medium, insulin gene expression up-regulating growth factors, hormones and antibiotics for 3 days. They were studied for transcriptional factors: paired box genes-6 (Pax-6), Islet-1 transcriptional factor (Isl-1) and pancreatic and duodenal homobox-6 (Pdx-6) (immunofluorescence). C-peptide and insulin were measured by chemiluminescence. In-vitro glucose sensitivity assay was carried out by measuring levels of insulin and C-peptide secretion in absence of glucose followed by 2 hours incubation after glucose addition. MSC cultured without use of differentiation medium was used as negative control. Results: Total 50 IS-MSC cell lines were generated from h-AD derived MSC. Hematoxylin and eosin stained cells showed large basophilic nuclei with distinct margins surrounded by eosinophilic cytoplasm. The mean cell quantum was 3.16 ± 0.58 ml (range: 2-4 ml), mean cell count, 2.5 ± 0.95 x10 4 /ml (0.78-2.7 x10 4 /ml), mean CD45-/90+ cells were 47.39 ± 15.77 % (range: 16.62-81.38%) and mean CD45-/73+ cells were 25.40 ± 13.03 % (range: 2.68-65.72%). All the IS-MSC showed presence of transcriptional factors Pax-6, Isl-1, pdx-1. Mean insulin level secreted by the cells themselves was 165.42 ± 665.85 mU/ml (0-3800 mU/ml) in absence of glucose and 2 hours after addition of glucose (following incubation at 37°C) the rise in insulin secretion level was observed with the mean of 510.41 ±1502.24 mU/ml (range: 0.5-9500 mU/ml). Mean C-peptide level secreted by the cells themselves was 0.32 ± 0.42 ng/ml (range: 0-2.26 ng/ml) in absence of glucose and after 2 hours after addition of glucose the rise in C-peptide secretion level was observed with the mean of 1 ± 1.67 ng/ml (range: 0.01-9.35 ng/ml). The mean rise in insulin and C-peptide secretion levels secreted by the cells themselves was 3.08 folds (P=0.00001) and 3.14 folds (P=< 0.0001) respectively after...