OBJECTIVE: To evaluate the fixation strength and tissue reaction of the glue fixation and self-stabilizing leg fixation methods and to compare the results with those of the conventional tagging suture fixation method. MATER AND METHODS: Twelve healthy rabbits were selected and three different methods of implanting the port chamber were employed on the back of each rabbit. A total of thirty six port chambers were implanted with these three different methods, viz. the glue fixation method using tissue adhesive, the self-stabilizing leg method using a self-expandable stabilizing leg, and the suture fixation method. The fixation strength and the gross and histopathologic changes of each fixation method were evaluated at three days, one week, two weeks and four weeks after port implantation. RESULTS: The glue fixation method showed a good fixation strength, which was similar to that of the tagging suture method (p=0.3486). Five of the six ports (83%) implanted with the glue fixation method which were examined after two weeks showed cracks on the external surface, but this had no adverse effects on their function. A large amount of granulation tissue reaction was found at the bottom of the chamber (p=0.0025). The fixation with the self-stabilizing leg showed relatively lower fixation strength (p=0.0043), but no turning-over of the chamber occurred. The fixation strength improved with time after the first week, and minimal granulation tissue reaction was observed with this method. CONCLUSION: The glue fixation method exhibited equal fixation strength compared to the suture fixation, but showed cracking and a large amount of granulation tissue, whereas the fixation with a self-stabilizing leg showed weaker fixation strength.
Alloys ; Animals ; Capillaries/cytology/metabolism/pathology ; Cell Proliferation ; Device Removal ; Enbucrilate/therapeutic use ; *External Fixators ; Fibroblasts/metabolism/pathology ; Granulation Tissue/blood supply/metabolism/pathology ; *Implants, Experimental ; Models, Animal ; Rabbits ; Sutures/*utilization ; Time Factors ; Tissue Adhesives/*therapeutic use

OBJECTIVETo study the acting mechanism of Cordyceps mycelia extract (CME) for antagonizing hepatic sinusoidal capillarization (HSC) in rats with dimethylnitrosamine (DMN) induced liver cirrhosis.

METHODSRat liver cirrhosis model was established by peritoneal injection of DMN 10 mg/kg 3 times a week for 4 weeks. To rats in the CME-prevented group CME were administrated at a dose of 10 mL/kg, once a day, for 4 weeks. The observation time points were scheduled on the 3rd day (d3), and at the end of the 2nd (W2) and 4th week (W4) after modeling, and the following items were observed: hepatic ultrastructure was observed under electron microscope; expressions of CD44, von Willebrand factor (vWF) and type IV collagen (Col lV) in the liver sinusoidal walls by immunohistochemistry; matrix metalloproteinase-2 and-9 (MMP-2, MMP-9) activity under zymogram method; and serum hyaluronic acid (HA) content by radioimmunoassay.

RESULTSObservation at d3 showed MMP-2 and MMP-9 activity significantly increased, Col IV deposition and CD44 positive staining decreased, vWF positive staining increased in the liver sinusoidal walls, the fenestrae in the sinusoidal endothelial cells (SECs) decreased, and serum HA content increased (P<0.05); at W4, SECs defenestration and sub-SECs basal membrane formation were shown. In the CME-prevented group MMP-2 and MMP-9 activity significantly decreased (P<0.05); defenestration and basal membrane formation alleviated in the early stage (d3, W4); and at W2 and W4 decreases of HA content and vWF positive staining were shown, with increase of CD44 positive staining (P<0.05), more SECs fenestrae, and alleviated basal membrane formation.

CONCLUSIONSThe elevation of MMP-2 and MMP-9 activity in the early stage, which degrades the Col IV normally distributed under the sinusoidal endothelium, is an important factor for HSC formation. CME could inhibit the initiation of HSC by decreasing MMP-2 and MMP-9 activity in the early stage, and prevent its formation by decreasing SECs injury and phenotypic changes.

Animals ; Capillaries ; pathology ; Cordyceps ; Dimethylnitrosamine ; adverse effects ; Hepatic Veins ; cytology ; drug effects ; pathology ; Liver ; blood supply ; Liver Cirrhosis, Experimental ; pathology ; Male ; Matrix Metalloproteinase 2 ; metabolism ; Matrix Metalloproteinase 9 ; metabolism ; Mycelium ; Neovascularization, Pathologic ; prevention & control ; Rats ; Rats, Wistar

OBJECTIVETo investigate the potential effect of homologous bone marrow mesenchymal stem cells (MSCs) on repairing peri-tubular capillary cluster (PTCC), and on improving renal tubular and mesenchymal hypoxia condition.

METHODSMonocyte was purified from bone marrow, amplified and identified as MSCs in vitro. Thirty female Wistar rats were randomly divided into 3 groups, the normal control group (Group A), MSCs transplanted group (Group B) and un-transplanted group (Group C). Rats in Group A was administered with drinking water by gastrogavage for 12 weeks, while those in Group B and C were administered with Aristolochia Decoction for 12 weeks to establish chronic aristolochic acid nephropathy (CAAN) model. At the end of the 12th week, 1 ml of MSCs was injected through caudal vein to the rats in Group B, while to those in Group A and C normal saline was injected instead. Blood, urine and kidney tissue of rats were collected at the end of the 16th week for examination, and their kidney tissue were made into serial section for determining the distribution of Y chromosome and CD34 double positive cells, and the pathological, immunohistochemical changes were observed using Western blotting and RT-PCR, etc.

RESULTSY chromosome and CD34 double positive cells could be seen in MSCs transplanted renal tissue in group B. At the end of the 16th week, the PTCC density in Group C and B was (26.47 +/- 1.56)/ 0.13 mm2 and (5.26 +/- 0.78)/0.13 mm2 respectively, and the IOD value of hypoxia inducible factor-1alpha (HIF-1alpha) in them was (6.74 +/- 0.67) x 10(3) and (25 27 +/- 1.46) x 10(3) respectively, all showing significant difference between the two groups (P < 0.01). The content of CD34 was higher in Group B than that in Group C (P < 0.01).

CONCLUSIONHomologous MSCs can enhance the vascular endothelial cells differentiation to repair the PTCC, thus to improve the renal tubular and mesenchymal hypoxia status.

Animals ; Antigens, CD34 ; biosynthesis ; genetics ; Aristolochic Acids ; Blotting, Western ; Bone Marrow Cells ; cytology ; Bone Marrow Transplantation ; methods ; Capillaries ; abnormalities ; metabolism ; Endothelial Cells ; metabolism ; pathology ; Female ; Immunohistochemistry ; Kidney Diseases ; chemically induced ; pathology ; surgery ; Kidney Tubules ; blood supply ; pathology ; Male ; Mesenchymal Stem Cell Transplantation ; methods ; Mesenchymal Stromal Cells ; cytology ; RNA, Messenger ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Reverse Transcriptase Polymerase Chain Reaction ; Transplantation, Homologous