scholarly journals Morphological aspects of orbital defect reconstruction in rats with elastin-based biomaterial

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Anna Lebedeva ◽  
Rafik Nigmatullin ◽  
Rinat Kutushev

The objective of the study was to identify morphological aspects of replacement of xenogeneic decellularized elastin matrix (ХDEM) transplanted into a bone defect of the upper orbital wall in rats. Materials and methods. The experiment was performed on 60 Wistar rats with artificially created 7×4 mm defect in the upper edge of their orbit. In the experimental group (n=30), DХEM was placed in the defect area. Its size matched the size of the defect, and it was attached with a suture material (50 μm silk). Soft tissues were sutured layer by layer in the control group (n=30). Tissue excision was performed after 1, 3 and 12 months. Histological, immunohistochemical and electron microscopic methods were employed. Results. We were gradually replacing DХEM with bone tissue against the background of a pronounced reaction of CD68+/MMP-9+ macrophages, which implied its resorption and lysis. Osteogenesis occurred via intramembranous ossification and endochondral ossification, which was preceded by centripetal migration of endothelial kidneys with subsequent differentiation into capillaries and overgrowth of loose fibrous connective tissue containing progenitor cells. The microenvironment, represented by reticulin fibers, TGF-β1, and sulfated glycosaminoglycans, could contribute to the differentiation of progenitor cells in the osteogenic direction and to osteogenesis per se. In the control group, the defect remained open throughout the experiment. Conclusion. Decellularized biomaterial, based on elastin matrix, has osteoconductive and osteoinductive properties and can serve an adequate biomimetic for reconstruction of the bone defects.

Author(s):  
Tomoo Kawada ◽  
Michio Arakawa ◽  
Kenjiro Kambara ◽  
Takashi Segawa ◽  
Fumio Ando ◽  
...  

We know that alloxan causes increased-permeability pulmonary edema and that alloxan generates oxygen radicals (H2O2, O2−, ·OH) in blood. Therefore, we hypothesize that alloxan-generated oxygen radicals damage pulmonary capillary endothelial cells, and, possibly, alveolar epithelial cells as well. We examined whether oxygen radical scavengers, such as catalase or dimethylsulfoxide (DMSO), protected against alloxaninduced pulmonary edema.Five dogs in each following group were anesthetized: control group: physiological saline (20ml/kg/h); alloxan group: physiological saline + alloxan (75mg/kg) bolus injection at the beginning of the experiment; catalase group: physiological saline + catalase (150,000u/kg) bolus injection before injection of alloxan; DMSO group: physiological saline + DMSO (0.4mg/kg) bolus injection before alloxan. All dogs had 30-min baseline period and 3-h intervention period. Hemodynamics and circulating substances were measured at the specific points of time. At the end of intervention period, the dogs were killed and had the lungs removed for electron microscopic study and lung water measurement with direct destructive method.


1981 ◽  
Vol 45 (03) ◽  
pp. 276-281 ◽  
Author(s):  
S Ishimaru ◽  
E Berglin ◽  
H-A Hansson ◽  
A-C Teger-Nilsson ◽  
G William-Olsson

SummaryA segment of the inferior vena cava was replaced by an expanded polytetrafluoroethylene graft in 13 dogs. Five of them served as a control group, while the other 8 were moderately or severely defibrinogenated with subcutaneous batroxobin. Plasma fibrinogen decreased to extremely low values throughout the experiment in the defibrinogenated dogs except in the moderately treated group in which it temporarily rose to 0.72-0.87 g/1 on the first postoperative day.Scanning electron microscopic observations of the haemostatic clot formed at the anastomoses of the graft revealed no significant morphological differences in platelet adhesion and/or aggregation between the three groups. These findings confirmed that platelets play a key role in primary haemostasis during defibrinogenation.The fibrin network was slightly diminished and only short fibrin filaments could be seen in the moderately and severely defibrinogenated groups respectively. These differences in composition of the clots are discussed in relation to their haemostatic capacity.


2021 ◽  
Vol 22 (7) ◽  
pp. 3505
Author(s):  
Flavy Roseren ◽  
Martine Pithioux ◽  
Stéphane Robert ◽  
Laure Balasse ◽  
Benjamin Guillet ◽  
...  

Granulocyte colony-stimulating factor (G-CSF) was shown to promote bone regeneration and mobilization of vascular and osteogenic progenitor cells. In this study, we investigated the effects of a systemic low dose of G-CSF on both bone consolidation and mobilization of hematopoietic stem/progenitor cells (HSPCs), endothelial progenitor cells (EPCs) and mesenchymal stromal cells (MSCs) in a rat model of distraction osteogenesis (DO). Neovascularization and mineralization were longitudinally monitored using positron emission tomography and planar scintigraphy. Histological analysis was performed and the number of circulating HSPCs, EPCs and MSCs was studied by flow cytometry. Contrary to control group, in the early phase of consolidation, a bony bridge with lower osteoclast activity and a trend of an increase in osteoblast activity were observed in the distracted callus in the G-CSF group, whereas, at the late phase of consolidation, a significantly lower neovascularization was observed. While no difference was observed in the number of circulating EPCs between control and G-CSF groups, the number of MSCs was significantly lower at the end of the latency phase and that of HSPCs was significantly higher 4 days after the bone lengthening. Our results indicate that G-CSF accelerates bone regeneration and modulates mobilization of progenitor cells during DO.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1097.1-1097
Author(s):  
F. Zhu ◽  
X. Zhang

Background:Connective tissue disease-associated interstitial lung disease (CTD-ILD) is a class of refractory diseases.Non-specific treatment with hormone and immunosuppressive agents is mostly used at present, but the effect is limited and the long-term survival rate is not improved [1],while anti-fibrosis treatments (such as Pirfenidone and Nintedanib) have only recently been approved, the long-term efficacy is still unknown.Tofacitinib(TOFA), a JAK inhibitor, has recently been used to treat patients with severe dermatomyositis related interstitial pulmonary disease, with significantly improved survival rate [2-4].A basic study showed that TOFA improved interstitial pulmonary disease in mice by promoting the proliferation of myelogenic inhibitory cells [5].However, whether TOFA can affect the migration and invasion of human lung fibroblasts and further research to reveal the mechanism of its inhibition of pulmonary fibrosis has not been reported.Objectives:To investigate the anti - fibrosis effect of TOFA in CTD-ILD.Methods:Cell migration and invasion AssaysHLFs were incubated with TOFA for 72h, followed by TGF- β1 for 24h.DMEM serum-free medium was used to determine the cell density to 5. 0 × 107/L, 600 uL medium containing 10% fetal bovine serum was added to the lower compartment of Transwell chamber, and 200 uL cell suspension was added to the upper compartment.Incubate in incubator for 12 h.After fixation, staining and sealing, the cells were observed and counted under a microscope. At least 5 random field transmembrane cells were counted in each hole, and the mean value was taken.For the invasion assays, Transwell chamber coated with matrigel was used, and the cell incubation time was 16 h.Results:1. Effect of TOFA on HLFs migration function (Figure 1)Figure 1.Effect of TOFA on HLFs migration function(×200).Mean ± SEM. n = 5.The number of cells passing through the biofilm in the three groups was counted.It can be seen that TGF-β1 group significantly increased compared with control group (*P < 0.0001), and TOFA group significantly decreased compared with TGF- β1 group (#P < 0.0001), suggesting that TOFA can significantly inhibit TGF-β1- induced HLFs migration.2. Effect of TOFA on HLFs invasion function (Figure 2)Figure 2.Effect of TOFA on HLFs invasion function(×200).Mean ± SEM. n = 5.The number of cells passing through the matrigel in the three groups was counted.It can be seen that TGF-β1 group was significantly higher than the control group (*P < 0.0001), and TOFA group was significantly lower than TGF-β1 group(#P < 0.001), suggesting that TOFA can significantly inhibit the invasion function of HLFs induced by TGF-β1.Conclusion:TOFA can effectively inhibit the function of HLFs migration and invasion. Although further studies are needed to elucidate the mechanism by which TOFA inhibit the function of HLFs migration and invasion, our study suggests that TOFA has a potential therapeutic effect for CTD-ILD.References:[1]Aparicio, I.J. and J.S. Lee, Connective Tissue Disease-Associated Interstitial Lung Diseases: Unresolved Issues. Semin Respir Crit Care Med, 2016. 37(3): p. 468-76.[2]Kato, M., et al., Successful Treatment for Refractory Interstitial Lung Disease and Pneumomediastinum With Multidisciplinary Therapy Including Tofacitinib in a Patient With Anti-MDA5 Antibody-Positive Dermatomyositis. J Clin Rheumatol, 2019.[3]Kurasawa, K., et al., Tofacitinib for refractory interstitial lung diseases in anti-melanoma differentiation-associated 5 gene antibody-positive dermatomyositis. Rheumatology (Oxford), 2018. 57(12): p. 2114-2119.[4]Chen, Z., X. Wang, and S. Ye, Tofacitinib in Amyopathic Dermatomyositis-Associated Interstitial Lung Disease. N Engl J Med, 2019. 381(3): p. 291-293.[5]Sendo, S., et al., Tofacitinib facilitates the expansion of myeloid-derived suppressor cells and ameliorates interstitial lung disease in SKG mice. Arthritis Res Ther, 2019. 21(1): p. 184Disclosure of Interests:None declared


Author(s):  
Wagner Vargas Souza Lino ◽  
André Luis Lacerda Bachi ◽  
José Arruda Mendes Neto ◽  
Gabriel Caetani ◽  
Jônatas Bussador do Amaral ◽  
...  

Abstract Introduction Combination of chronic inflammation and an altered tissue remodeling process are involved in the development of Chronic Rhinosinusitis with Nasal Polyps (CRSwNP). Studies demonstrated that mesenchymal stem cells expressing the progenitor gene CD133 were involved in a significant reduction of the chronic inflammatory process in the polypoid tissue. Objective To evaluate the levels of CD133 (Prominin-1) in nasal polypoid tissue and its correlation with interleukin-8 (IL-8) and transforming growth factor β1 (TGF-β1). Methods A total of 74 subjects were divided in the following groups: control group (n = 35); chronic rhinosinusitis with nasal polyps nonpresenting comorbid asthma and aspirin intolerance (CRSwNPnonAI) group (n = 27); and chronic rhinosinusitis with nasal polyps presenting comorbid asthma and aspirin intolerance (CRSwNPAI) group (n = 12). Histologic analysis and also evaluation of the concentration of CD133, IL-8, and TGF-β1 by enzyme-linked immunosorbent assay (ELISA) kits were performed in nasal tissue obtained from nasal polypectomy or from middle turbinate tissue. Results Higher eosinophilic infiltration was found in both CRSwNP groups by histologic analysis. Lower levels of TGF-β1 and IL-8 were observed in both CRSwNP groups when compared with the control group, whereas the CD133 levels were significantly reduced only in the CRSwNPnonAI group compared with the control group. Conclusion It was demonstrated that the nasal mucosa presenting polyposis showed a significant reduction of CD133 levels, and also that this reduction was significantly correlated with the reduction of TGF-β1 levels, but not with IL-8 levels. Therefore, these findings may be involved in the altered inflammatory and remodeling processes observed in the nasal polyposis.


2020 ◽  
Vol 21 (19) ◽  
pp. 7374
Author(s):  
Gilberto Y. Nakama ◽  
Sabrina Gonzalez ◽  
Polina Matre ◽  
Xiaodong Mu ◽  
Kaitlyn E. Whitney ◽  
...  

Recent efforts have focused on customizing orthobiologics, such as platelet-rich plasma (PRP) and bone marrow concentrate (BMC), to improve tissue repair. We hypothesized that oral losartan (a TGF-β1 blocker with anti-fibrotic properties) could decrease TGF-β1 levels in leukocyte-poor PRP (LP-PRP) and fibrocytes in BMC. Ten rabbits were randomized into two groups (N = 5/group): osteochondral defect + microfracture (control, group 1) and osteochondral defect + microfracture + losartan (losartan, group 2). For group 2, a dose of 10mg/kg/day of losartan was administrated orally for 12 weeks post-operatively. After 12 weeks, whole blood (WB) and bone marrow aspirate (BMA) samples were collected to process LP-PRP and BMC. TGF-β1 concentrations were measured in WB and LP-PRP with multiplex immunoassay. BMC cell populations were analyzed by flow cytometry with CD31, CD44, CD45, CD34, CD146 and CD90 antibodies. There was no significant difference in TGF-β1 levels between the losartan and control group in WB or LP-PRP. In BMC, the percentage of CD31+ cells (endothelial cells) in the losartan group was significantly higher than the control group (p = 0.008), while the percentage of CD45+ cells (hematopoietic cells-fibrocytes) in the losartan group was significantly lower than the control group (p = 0.03).


2020 ◽  
Vol 2020 ◽  
pp. 1-10 ◽  
Author(s):  
M. Al Bahrawy ◽  
K. Ghaffar ◽  
A. Gamal ◽  
K. El-Sayed ◽  
V. Iacono

Background. In the field of periodontal guided tissue regeneration, microperforated membranes have recently proved to be very promising periodontal regenerative tissue engineering tools. Regenerative periodontal approaches, employing gingival mesenchymal stem/progenitor cells in combination with these novel membranes, would occur mostly in inflamed microenvironmental conditions intraorally. This in turn entails the investigation into how inflammation would affect the proliferation as well as the migration dynamics of gingival mesenchymal stem/progenitor cells. Materials and Methods. Clones of human gingival mesenchymal stem/progenitor cells (GMSCs) from inflamed gingival tissues were characterized for stem/progenitor cells’ characteristics and compared to clones of healthy human GMSCs (n=3), to be subsequently seeded on perforated collagen-coated poly-tetra-floro-ethylene (PTFE) membranes with a pore size 0.4 and 3 microns and polycarbonic acid membranes of 8 microns pore size in Transwell systems. The population doubling time and the MTT test of both populations were determined. Fetal bovine serum (FBS) was used as a chemoattractant in the culturing systems, and both groups were compared to their negative controls without FBS. Following 24 hours of incubation period, migrating cells were determined on the undersurface of microperforated membranes and the membrane-seeded cells were examined by scanning electron microscopy. Results. GMSCs demonstrated all predefined stem/progenitor cell characteristics. GMSCs from inflamed gingival tissues showed significantly shorter population doubling times. GMSCs of inflamed and healthy tissues did not show significant differences in their migration abilities towards the chemoattractant, with no cellular migration observed in the absence of FBS. GMSCs from healthy gingival tissue migrated significantly better through larger micropores (8 microns). Scanning electron microscopic images proved the migratory activity of the cells through the membrane pores. Conclusions. Inflammation appears to boost the proliferative abilities of GMSCs. In terms of migration through membrane pores, GMSCs from healthy as well as inflamed gingival tissues do not demonstrate a difference in their migration abilities through smaller pore sizes, whereas GMSCs from healthy gingival tissues appear to migrate significantly better through larger micropores.


1980 ◽  
Vol 152 (2) ◽  
pp. 419-437 ◽  
Author(s):  
I Goldschneider ◽  
D Metcalf ◽  
F Battye ◽  
T Mandel

A scheme is presented whereby pluripotent hemopoietic stem cells (PHSC) from rat bone marrow can be enriched 320-fold with the aid of the fluorescence- activated cell sorter. This scheme is based on the observations that PHSC are strongly positive for Thy-1 antigen (upper 10th percentile); have light- scattering properties (size distribution) between those of bone marrow lymphocytes and myeloid progenitor cells; and are relatively resistant to cortisone. It is estimated that PHSC may constitute 80 percent of the cells isolated according to these parameters. Candidate PHSC are described at the light and electron microscopic levels. At least two populations of accessory cells appear to influence the number and/or the nature of the hemopoietic colonies that form in the in vivo spleen colony-forming unit assay. Putative amplifier cells are strongly Thy-1(+) and cortisone sensitive; putative suppressor cells are weakly Thy-1(+) and cortisone resistant. Three subsets of granulocyte (G) -macrophage (M) progenitor cells (in vitro colony-forming cells [CFC]) are identified on the basis of relative fluorescence intensity for Thy-1 antigen: G-CFC are strongly Thy-l(+); M-CFC are weakly Thy-l(+); and cells that produce mixed G and M CFC have intermediate levels of Thy-1. GM-cluster-forming cells and mature G and M are Thy-1(-). The results suggest that G-CFC are bipotential cells that give rise to G and M-CFC; and that the latter produce mature M through a cluster- forming cell intermediate. Thy-1 antigen is also demonstrated on members of the eosinophil, megakaryocyte, erythrocyte, and lymphocyte cell series in rat bone marrow. In each instance, the relative concentration of Thy-1 antigen is inversely related to the state of cellular differentiation.


2014 ◽  
Vol 23 (11) ◽  
pp. 1451-1464 ◽  
Author(s):  
Hiroki Iwai ◽  
Satoshi Nori ◽  
Soraya Nishimura ◽  
Akimasa Yasuda ◽  
Morito Takano ◽  
...  

Transplantation of neural stem/progenitor cells (NS/PCs) promotes functional recovery after spinal cord injury (SCI); however, few studies have examined the optimal site of NS/PC transplantation in the spinal cord. The purpose of this study was to determine the optimal transplantation site of NS/PCs for the treatment of SCI. Wild-type mice were generated with contusive SCI at the T10 level, and NS/PCs were derived from fetal transgenic mice. These NS/PCs ubiquitously expressed ffLuc-cp156 protein (Venus and luciferase fusion protein) and so could be detected by in vivo bioluminescence imaging 9 days postinjury. NS/PCs (low: 250,000 cells per mouse; high: 1 million cells per mouse) were grafted into the spinal cord at the lesion epicenter (E) or at rostral and caudal (RC) sites. Phosphate-buffered saline was injected into E as a control. Motor functional recovery was better in each of the transplantation groups (E-Low, E-High, RC-Low, and RC-High) than in the control group. The photon counts of the grafted NS/PCs were similar in each of the four transplantation groups, suggesting that the survival of NS/PCs was fairly uniform when more than a certain threshold number of cells were transplanted. Quantitative RT-PCR analyses demonstrated that brain-derived neurotropic factor expression was higher in the RC segment than in the E segment, and this may underlie why NS/PCs more readily differentiated into neurons than into astrocytes in the RC group. The location of the transplantation site did not affect the area of spared fibers, angiogenesis, or the expression of any other mediators. These findings indicated that the microenvironments of the E and RC sites are able to support NS/PCs transplanted during the subacute phase of SCI similarly. Optimally, a certain threshold number of NS/PCs should be grafted into the E segment to avoid damaging sites adjacent to the lesion during the injection procedure.


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