Biomedical subjects

Jingcong Luo

Publications and source records attributed to Jingcong Luo.

15 recordsLinked to original sources

PubMed2006

[A comparative study on acellular small intestinal submucosa and acellular amnion as dressings for traumatic skin defects].

OBJECTIVE: To compare the reparative effects between the acellular small intestinal submucosa and the acellular amnion as dressings for traumatic skin defects. METHODS: Three full-thickness skin defects, which were close to the vertebral column of the pig, were created on both sides of the dorsum. The skin defects were randomly divided into three groups. In each group, the following different materials were used to cover the skin defects: the acellular amnion in Group A, the acellular small intestinal submucosa (SIS) in Group B, and the physiological saline gauze in Group C (the control group). The specimens from the skin defects were harvested for a histological evaluation and for determination of the hydroxyproline content at 10 (2 pigs), 20 (2 pigs), and 30 days (3 pigs). We observed the healing process of the wound and its healing rate, counted the inflammatory cells, vascular endothelial cells, and proliferating cells, and determined the hydroxyproline content. RESULTS: The acellular amnion in Group A and the acellular SIS in Group B adhered to the wound tightly, but they did not adhere to the dressing; when the dressing was changed, the wound did not bleed. The saline gauze in Group C adhered to the wound tightly, but when the dressing was changed, the wound bled until 22 days after operation. Under the microscope, the collagen in the tissue below the epithelium was arranged more regularly and there were fewer cells concerned with inflammation in Groups A and B than in Group C at 10, 20, and 30 days after operation. At 10, 20, and 30 days after operation, the wound healing rate was greater in Groups A and B than in Group C. The number of the inflammatory cells and the proliferating cells were greater in Group C than in Groups A and B. There was a statistically significant difference (P < 0.05), At 20 and 30 days after operation, the content of hydroxyproline was greater in Group C than in Group A and B. There was a statistically significant difference (P < 0.05). However, there was no statistically significant difference between Group A and Group B in the wound healing rate, the numbers of the inflammatory cells, vascular endothelial cells and proliferating cells, and the content of hydroxyproline (P > 0.05). There was no statistically significant difference among the three groups in the number of the vascular endothelial cells. CONCLUSION: Compared with Group C, the wound healing rate is improved, the collagen in the tissue below the epithelium is arranged more regularly, and the inflammatory cells, bleeding, and effusion are reduced in Groups A and B. The reparative effects of the acellular amnion and the acellular small intestinal submucosa as dressings on the skin defects are almost the same.

Amnion↗

PubMed2006

[Study on small intestinal submucosa as repair materials in urethral reconstruction].

OBJECTIVE: To explore the possibility of small intestinal submucosa (SIS) for reconstruction of urethral defect. METHODS: Twenty-four male rabbits were divided into 4 groups: group A (the tubular SIS graft for urethral repair), group B (control group, urethral tubular defect), group C (the SIS patch graft for urethral repairs), group D (control group, urethral part defect). Then the regenerative segment was studied with histological technique by hematoxylin-eosin straining and immunohistological straining for alpha-actin after 6 and 12 weeks postoperatively. The retrograde urethrography and urodynamics were used to evaluate the function of the regenerative urethra at 12 weeks after operation. RESULTS: In groups A and C, at 6 weeks after operation, the luminal surface of matrix was completely covered by urothelium, minimal SIS graft was observed in the extracellular matrix, new smooth-muscle cells was confirmed; however, more inflammatory cells were observed in the host-matrix anastomosis in group A than in group C. At 12 weeks postoperatively, the regenerative tissue was equivalent to the normal urethral tissue and SIS disappeared in group C, but some minimal SIS grafts were observed in group A. In groups B and D, urethral strictures and fibrous connective tissue were observed except 3 cases. The urethrography showed wide smooth urethral in group A and C, meanwhile urodynamic evaluation didn't demonstrate significant difference (P > 0.05) in the bladder volume and the maximum urethral pressure between preoperation and postoperation in group A or group C. CONCLUSION: SIS can be a useful material for urethral repair in rabbits, the SIS patch graft is superior to the tubular SIS graft in urethra reconstruction.

Acrylic Resins↗

PubMed2006

[Expressions of Cbfal and osterix in osteoblasts on human acellular amniotic membrane].

OBJECTIVE: To study the differentiation of the human osteoblasts during the construction of the tissue engineered periosteum with the human acellular amniotic membrane (HAAM). METHODS: To construct the tissue engineered periosteum (n=60) with HAAM, the human fetal osteoblasts were used. The fetal osteoblasts were cultured for 2, 4, 6, 8, and 10 days, and then their total RNA was extracted, which were reversely transcripted to cDNA. The real-time PCR analysis was used to reveal Cbfal and Osterix, and the cycle threshold (Ct) was also measured. The simply-cultured osteoblasts were used as the control group (n=20). RESULTS: The expression of Cbfal was higher in the experimental group on the 2nd day when compared with that on the 4th, 6th, and 8th day (P < 0.05). The same result existed on the 10th day when compared with that on the 4th and 8th day. The expression of Osterix increased and was highest on the 8th day when compared with the other results (P < 0.05). Both of the 2 gene expressions were decreased in the control group when compared with those in the experimental group, but with no significant difference (P > 0.05). CONCLUSION: Cbfal and Osterix can be normally expressed by the osteoblasts after their integration with HAAM. As a scaffold, HAAM can be used to keep the osteoblast phenotype and differentiation with an osteoconductive ability. Such a cell-scaffold complex may provide a basis for the osteogenesis.

Amnion↗

PubMed2005

[Experimental study on repair of goat tibia defect with marrow stromal cell and bio-derived bone].

OBJECTIVE: To investigate the feasibility of repairing goat tibia defect with marrow stromal cells (MSCs). METHODS: MSCs were cocultured with the bio-derived bone in vitro, and the 20 mm tibia defects were made and fixed with plate in 35 goats, and they were divided into the experimental group, control group and blank group. The defects on the right side were filled with tissue engineering bone as the experimental group, the defects on the left side with bio-derived bone as the control group in 33 goats, and the defect on the both sides were not filled with any materials as the blank group in 2 goats. The repair capability was assessed physically, histopathologically and biomechanically at 2, 4, 6, 8, 12, 16 and 24 weeks after operation in 3 groups. RESULTS: By physical, histopathological and biomechanical examinations, the bio-derived bone was partially absorbed in the experimental group and was rarely absorbed in the control group in the 4th week; the defects were partially repaired in the experimental group, and in the control group, few new bones were observed in the two ends of the implants, in which there was fibrous tissue. The effects of biomechanics had no statistically significant difference between the experimental group and the control group (P>0.05) in the 8th week; the defects were perfectly repaired in the experimental group and the effects of biomechanics had statistically significant difference between two groups (P<0.05) in the 12th weeks. The defects were not repaired in the 24th week in the blank group. CONCLUSION: The tissue engineering bone can efficiently repair bone defect, and its repair capability is better than that of bio-derived bone alone both in quantity and in quality of bone formation.

Animals↗

PubMed2005

[Experimental study on repairing segmental bone defect with bio-derived bone preserved by various methods].

OBJECTIVE: To study the difference of repairing segmental bone defect with bio-derived bone preserved by various methods. METHODS: Freeze-dried biomaterials had been stored in two different preservation solutions for three months, while the biomaterials stored for same period were observed as control group. The experimental model of 15 mm radial segmental defect was made in 60 New Zealand white rabbits, which were divided into groups A, B and C according to transplant materials preserved by various methods. Groups A and B were deeply divided into A1 and A2 subgroups, B1 and B2 subgroups according to whether materials were cocultured with osteoblasts. Tissue engineered bone was used to repair bone defects of left limbs in A1 and B1 subgroups, while simple material to repair defects of right limbs in A2 and B2 subgroups. Group C was divided into C1 and C2 subgroups. Freeze-dried material was used to repair bone defects of the left limbs, while defects of the right limbs as blank control group. The samples were harvested and observed by the roentgenographical, histomorphological, biomechanical and computerized graphical analysis at 4, 8 and 16 weeks. RESULTS: All of the defects treated with implants exhibited new bone formation 4, 8 and 16 weeks postoperatively, increasing with time. The radiological, histomorphological and biomechanical evaluation showed that the ability of new bone formation was arranged in 6 subgroups as follows: A1>A2>C1>B1>B2>C2, the difference was significant between them (P<0.001, P<0.05). The ability of new bone formation was strongest and at 16 weeks the defect was bridged with the appearance of marrow cavities in A1 subgroup, the biomechanical properties in implants approached to those of normal bone. CONCLUSION: The choice of proper preservation solution can improve the ability of repairing bone defect.

Animals↗

PubMed2005

[Expression of interleukin 2 and IL-2 receptor after implanted tissue engineered bones constructed with allogeneic marrow stromal stem cells and bio-derived materials in rhesus monkeys].

OBJECTIVE: To explore the feasibility of allogeneic marrow stromal stem cells (MSCs) as seed cells to construct tissue engineered bone by detecting the expressions of interleukin 2 (IL-2) and IL-2 receptor in rhesus monkeys after implanting these tissue engineered bones. METHODS: Engineered bones were constructed with osteoblasts which derived from allogeneic MSCs and bio-derived materials in vitro, and then were implanted to bridge 2.5 cm segmental bone defects of left radius in 15 rhesus monkeys as experimental group, bio-derived materials only were implanted to bridge same size defects of right radius as control group. Every 3 monkeys were sacrificed in the 1st, the 2nd, the 3rd, the 6th and the 12th weeks postoperatively and the expressions of IL-2 and IL-2 receptor in blood and graft samples were detected quantitatively by enzyme-linked immunosorbent assay (ELISA). RESULTS: There was no significant difference in the contents of IL-2 and its receptor between 2 groups (P>0.05). The contents of IL-2 and its receptor increased from the 2nd week and maintained high level from the 2nd to the 6th week, but decreased after 6 weeks. CONCLUSION: Tissue engineered bones constructed with allogeneic MSCs and bio-derived materials show low immunogenicity. Allogeneic MSCs may be used as seed cells to construct tissue engineered bone.

Animals↗

PubMed2005

[Experimental study of bone infection on WO-1 controlled-release system].

OBJECTIVE: To develop a new tissue engineering bone material which has an anti-infective function. METHODS: Collagen loaded bio-derived bone material was made by using type-I collagen and allograft bone. WO-1 was absorbed to collagen loaded bio-derived bone, then the morphological feature of the new bone material was observed by scanning electronic microscopy. 3H-tetracycline was diluted by WO-1 solution, and was absorbed to collagen loaded bio-derived bone, then the releasing kinetics of WO-1 was detected by 3H-tetracycline in vitro. WO-1 bio-derived bone material was grafted into a culture medium with staphylococcus aureus, Escherichia coli, and pseudomonas aeruginosa to observe its bacteriostasis ability. WO-1 bio-derived bone material was grafted into radius of defected rabbits, the concentration of WO-1 was detected on the 9th, 16th, 23th, and 30th day by HLPC in blood, in bone and in muscle. The bacteriostasis ability of WO-1 loaded bio-derived bone was tested in vitro and in vivo. RESULTS: WO-1 loaded bio-derived bone maintained natural network pore system and the surface of network pore system was coated with collagen membrane. The release of WO-1 from WO-1 loaded bio-derived bone showed bursting release on the 1st day, then showed stable release. WO-1 loaded bio-derived bone showed lasting and stable bacteriostasis to common pathogens of orthopaedic infections. The high concentration of WO-1 was observed in bone tissue and in muscle tissue at different time points and the difference among groups had no significance (P>0.05), while the concentration of WO-1 in blood was very low (P<0.05). CONCLUSION: WO-1 loaded bio-derived bone has good capability of drug controlled-release and bacteriostasis.

Animals↗

PubMed2005

[Morphological and biomechanical study on in vivo osteogenesis after repair of cranial defects with plastic engineered bone in rabbits].

OBJECTIVE: To investigate the morphology and biomechanics of in vivo osteogenesis after repairing rabbit skull defects with plastic engineered bone which was prefabricated with alginate gel, osteoblasts and bone granules. METHODS: Twenty-eight rabbits were divided into group A (n=16), group B (n=8) and group C (n=4). The bilateral skull defects of 1 cm in diameter were made. Left skull defects filled with alginate gel-osteoblasts-bone granules (group A1) and right skull defects filled with alginate gel-bone granules (group A2). The defects of group B was left, as blank control and group C had no defect as normal control. The morphological change and bone formation were observed by methods of gross, histology and biomechanics. RESULTS: In group A1, the skull defects were almost entirely repaired by hard tissue 12 weeks after operation. The alginate gel-osteoblasts-bone granule material had changed into bone tissue with few bone granules and some residuary alginate gel. The percentage of bone formation area was 40.92% +/- 19.36%. The maximum compression loading on repairing tissue of defects was 37.33 +/- 2.95 N/mm; the maximum strain was 1.05 +/- 0.20 mm; and loading/strain ratio was 35.82 +/- 6.48 N/mm. In group A2, the alginate and bone granules material partially changed into bone tissue 12 weeks after operation. The percentage of bone formation area was 18.51% +/- 6.01%. The maximum compression loading was 30.59 +/- 4.65 N; the maximum strain was 1.35 +/- 0.44 mm; and the loading/strain ratio was 24.95 +/- 12.40 N/mm. In group B, the skull defects were mainly repaired by membrane-like soft tissue with only few bone in marginal area; the percentage of bone formation area was 12.72% +/- 9.46%. The maximum compression loading was 29.5 +/- 2.05 N; the maximum strain was 1.57 +/- 0.31 mm; and the loading/strain ratio was 19.90 +/- 5.47 N/mm. In group C, the maximum compression loading was 41.55 +/- 2.52 N; the maximum strain was 0.95 +/- 0.17 mm; and the loading/strain ratio was 47.57 +/- 11.22 N/mm. CONCLUSION: The plastic engineered bone prefabricated with alginate gel-osteoblasts-bone granule may shape according to the bone defects and has good ability to form bone tissue, whose maximum compression loading can reach 89% of normal skull and the hardness at 12 weeks after operation is similar to that of normal skull.

Alginates↗

PubMed2005

[Experimental studies on preparation and property of scaffold material of bio-derived bone loading wo-1].

OBJECTIVE: To provide the chosen scaffold materials for experiment and application of tissue engineering and to detect the properties of the collagen bio-derived bone scaffold material loading WO-1. METHODS: The pure bio-derived bone scaffold material, bio-derived bone scaffold material loading collagen, collagen bio-derived bone scaffold material loading WO-1 were made by use of allograft bone, and type-I collagen, and WO-1. The morphological features, constitute components and mechanical properties were examined by scanning electron microscopy, X- rays diffraction and mechanical assay. RESULTS: The bio-derived bone scaffold material maintained natural network pore system; the bio-derived bone scaffold material loading collagen maintained natural network pore system, the surface of network pore system was coated by collagen membrane; the collagen bio-derived bone scaffold material loading WO-1 maintained natural network pore system, the surface of network pore system was coated by collagen membrane. The pore sizes of the 3 materials were 90-700 microm, 75-600 microm and 80-600 microm, respectively, and the porosities were 87.96%, 80.47%, 84.2%. There was no significant difference between them (P>0.05). The collagen bio-derived bone scaffold material loading WO-1 consisted of [HA,Ca10 (OH)2 (PO4)6. There was no significant difference in the mechanical strength of the three scaffold materials. CONCLUSION: The bio-derived bone scaffold material loading WO-1 is as good as bio-derived bone scaffold material and collagen bio-derived bone scaffold material, and it is an effective scaffold material for tissue engineering bone.

Biocompatible Materials↗

PubMed2005

[Elementary evaluation of small intestinal submucosa and polypropylene mesh used for repairing abdominal wall defect in rats].

OBJECTIVE: To compare the effect of small intestinal submucosa (SIS) and polypropylene mesh (PPM) on repairing abdominal wall defects in rats, and to probe into the feasibility of using SIS to repair the abdominal wall defects. METHODS: 100 SD rats (50 males and 50 females)were randomly divided into 2 groups (n = 50). Their weight ranged from 200 to 250 g. Full thickness abdominal wall defects (2 cmX 2 cm) were created by surgery and were repaired with SIS and PPM respectively. At different postoperative time (1st, 2nd, 4th, 8th and 12th week), animals were sacrificed to make histological observation. The tensile strength and the development of adhesions were measured and observed. RESULTS: 95 animals survived and were healthy after surgery. No inflammatory response and obvious immunoreaction were observed in both groups. One week after operation, the tensile strength of abdominal wall in SIS group (204.30+/-5.13 mmHg) was lower than that in PPM group(240.0+/-10.0 mmHg) at 1st week (P<0.05), and there were no difference at 4th, 8th, 12th week. Adhesions were more marked in PPM group than that in SIS group (P<0.05). CONCLUSION: Both SIS and PPM are histologically compatible when used in rats and can maintain sufficient tensile strength. SIS is superior to PPM in regards to tissue compatibility and adhesion formation.

Abdominal Injuries↗

PubMed2004

[Bio-tribological properties of dental prosthesis made of nitriding titanium alloy material].

Titanium alloy material (TC4) samples were treated with nitriding technique. The dynamic friction and wear behavior of the modified layer were examined on a reciprocating sliding rig in artificial saliva. Microhardness, depth profile and wear mechanisms were investigated by means of MVK-H12, TALYSURF6, XPS and microscopy. The results demonstrate that after being treated with nitriding technique the titanium alloy material (TC4) has better tribological behavior and up-graded wear resistance. The wear mechanism involves adhesion.

Adsorption↗

PubMed2004

[Effect of various storage methods on cellular compatibility of bio-derived bone].

OBJECTIVE: To study the effect of various storage methods on cellular compatibility of bio-derived bone. METHODS: Freeze-dried biomaterials had been stored in two different preservation solutions for three months, while the biomaterials stored for the same time were observed as control group. The experiment was divided into groups A, B, C and D according to different storage methods (group A: with materials stored in preservation solution 1; group B: with materials stored in preservation solution 2; group C: with freeze-dried materials; and group D: simple osteoblasts). Osteoblasts at 2 x 10(6)/ml had been cocultured with materials for 1, 3, 5, and 7 days. The cell-material complex was observed under phase microscope and electronic scanning microscope to evaluate the adhesion and growth of osteoblasts; the cell viability and alkaline phosphatase(ALP) activity were measured, and the cell cycle was analysed by flow cytometer. RESULTS: Osteoblasts adhered to materials preserved by different methods, differentiated and proliferated in the hole of materials. The difference of cell viability was not significant between three groups on day 1 and day 3. The cell viability of osteoblasts adhered to three materials was A > C > B group on day 5 and day 7 (P < 0.01, P < 0.05). The ALP activity of osteoblasts adhered to three materials was A > C > B group on day 7 (P < 0.01). The cell cycle of different groups did not change significantly, the abnormal cells were not seen. CONCLUSION: The choice of proper preservation solution can optimize the cellular compatibility of bio-derived bone.

Alkaline Phosphatase↗

PubMed2004

[Application of hard tissue slicing in research of bone tissue engineering].

OBJECTIVE: To improve the method of hard tissue slicing for research of bone tissue engineering. METHODS: The method of hard tissue slicing especially the key technique-slice mounting had been studied and improved. RESULTS: The experiments showed that our research improved techniques in hard tissue slicing not only in keeping the characteristics of hard tissue slicing, easily stain with HE, Masson, immunohistochemistry, and distinguishing the differences among tissues easily, but also in overcoming the shortcoming of issue shedding easy to happen in the general hard tissue slicing. CONCLUSION: The improved techniques in hard tissue slicing is a more useful hard tissue slicing techniques.

Animals↗

PubMed2004

[Effect of human acellular amnion membrane on tendon adhesion in rat].

OBJECTIVE: To investigate the effects of human acellular amnion membrane on SD rat tendon adhesion and to obtain the experimental data for clinical application in preventing postoperative tendon adhesion. METHODS: The tendons of 28 adult SD rats hindlimb were cut and sutured. The tendons of left hindlimb were encapsulated by human accellular amnion membrane as the experimental group and the ones of the other side were not encapsulated as control group. The rats were killed 1, 2, 4, 6, 8 and 12 weeks after operation. The results were evaluated grossly and histologically. RESULTS: There were no differences in healing of injury tendon and inflammatory response between the two groups. The anatomical and histological results showed the experimental group had less adhesion than the control group (P < 0.05). CONCLUSION: Human acellular amnion membrane can prevent adhesion of tendon without affecting tendon healing and is an optimal biological material to prevent tendon adhesion.

Amnion↗

PubMed2004

[Cellular compatibility of small intestinal submucosa in vitro].

This study was aimed to evaluate the cellular compatibility of the small intestinal submucosal(e) (SIS). Prepared by use of pig jejunum. SIS were cocultured with human embryonic periosteal osteoblasts (HEPOB), human embryonic skin fibroblasts (HESFB) and rabbit renal vascular endothelial cells (RRVEC) respectively. The cell growth, attachment, cell cycle, cell apoptosis rate were detected to evaluate the cellular compatibility of SIS. The three kinds of cells attached onto SIS and grew well. SIS accelerated the growth of RRVEC. No effects of SIS were detected on cell cycle and cell apoptosis rate in the three kinds of cells. SIS has good cellular compatibility without cytotoxicity. The porous structure of SIS is suited for the growth of HEPOB, HESFB and RRVEC in three dimensions in the scaffold. SIS is a good bio-derived material of tissue engineering.

Animals↗