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Chi-yu Jia

Publications and source records attributed to Chi-yu Jia.

13 recordsLinked to original sources
PubMed2006

[Isolation, culture and identification of adult epidermal stem cell].

OBJECTIVE: To explore and establish a new method of isolation, culture, and identification of adult epidermal stem cell in vitro for the provision of seed-cells in tissue engineering of skin. METHODS: Epidermis was obtained by digesting human foreskin with protease and it was dissociated into single cells with trypsin and ethylenediaminetetraacetic acid (EDTA). These single epidermis cells were inoculated onto human collagen IV coated flasks and cultured at 37 degrees C in a humidified atmosphere containing 5% CO(2). The nonadherent cells were rinsed off 10-15 minutes after inoculation. The adherent cells were observed under phase contrast microscope and electron microscope, and they were identified with immunocytochemical methods. Cell cycles of the adherent cells were determined with flow cytometry. RESULTS: With phase contrast microscope, the rapidly adherent cells were observed to form colonies 24 hours after inoculation. Immunocytochemistry showed the rapidly adherent cells were positive for beta1-integrin and keratin 19. Cell cycles showed that about 86.83% cells were in resting state/pre-DNA-synthetic gap (G0/G1 phase). Electron microscopy revealed that the rapidly adherent cells were immature. CONCLUSION: This study shows that adult epidermal stem cells could be isolated and cultured in vitro successfully.

Adult↗
PubMed2006

[Clinical management of deep facial burn].

OBJECTIVE: To explore the better clinical methods for the management of deep facial burn with optimal quality. Methods Fifty-four patients with deep facial burns were enrolled in the study and were divided into delayed skin grafting group (n=48) and early escharectomy group (n=6). In delayed grafting group, after the erosion of new born granulation tissue to the basal layer with blade holder or with peel or eschar shaving method at 3 postburn weeks (PBW) according to the eschar separation and granulation growth status, the whole face of the patients were divided into 10 regions and were then covered by split thickness auto skin. The same treatment was performed on the patients in early escharectomy group at 1 PBW. Physical therapy and plastic surgery were applied after skin grafting, and the patients were followed up from 3 month to 11 years. The first operation time, postburn facial operation time, operation times to repair the whole face, blood content of Hb, the amount of blood transfusion and hemorrhage and the prognosis were compared between the two groups. RESULTS: There was no difference between the two groups in regards to the first operation time, the total operation times,blood concentration of Hb before and after operation,and the amount of blood transfusion during the operation (P > 0.05). The operation time in delayed grafting group (21.9 +/- 3.2) d was obviously later than that in early escharectomy group (12.6 +/- 1.3) d, (P < 0.05). And there was evidently less amount of hemorrhage during operation(98 +/- 52) ml/100 cm2 than that in early escharectomy group (331 +/- 121) ml/100 cm2 (P < 0.01). The facial appearance of the patients in delayed grafting group was plump with more elasticity and richer expression compared with those in early grafting group. There exhibited different degrees of microstomia and both eyebrow defect in both groups during and after 1 postoperative year. In addition, mild to moderate ectropion and hypertrophic scar on the conjunction of grafted skin could appear in 80% of these patients. These deformities might be corrected by several times of plastic surgery. CONCLUSION: Based on the principle of arranging skin grafts according to the cosmetic and functional area units, split thickness skin grafting can provide satisfactory results for the repair of deep burn injury involving whole face when the wounds were treated with eschar peeling, tangential excision, escharectomy, granulation tissue scaling, or early escharectomy. In comparison with early escharectomy, eschar peeling, tangential excision, escharectomy, or granulation tissue scaling can get better results with less bleeding, full and round facial appearance, more elasticity of grafted skin and richer facial expression appearance after the operation. Meanwhile, effective physical therapy and scheduled plastic surgery after skin grafting can also be very important in achieving cosmetic results in the repair and reconstruction of whole facial deep burn.

Adolescent↗
PubMed2006

[Analysis of the quality of papers dealing with clinical trails in "Chinese Journal of Burns" during 2000-2004 by the standard of evidence-based medicine].

OBJECTIVE: To investigate the quality of reports of clinical results concerning burn injury, in order to raise the standard of clinical study of burn care in accordance to the standard of evidence-based medicine (EBM), with the aim of improving clinical research in burn care of this country. METHODS: All the papers of clinical study published in Chinese Journal of Burns (CJB) from 2000 to 2004 were evaluated according to EBM standard. RESULTS: There were 89 papers about clinical trials published in the past 5 years, in which 43 (48.3%) of the studies were carried out with random control trials (RCT), and 46 (51.7%) were clinical control trials (CCT). RCT papers increased year by year, while the number of CCT papers fluctuated greatly. The disparity in the quality of research was found as follows. In all the RCT and CCT papers, blinded research was adopted only in 5 papers (5.6%). Strict diagnostic standard including inclusion and exclusion standards were reported in 53 articles (59.6%). The comparison with baselines was not provided in 64 articles (71.9%). P value was given in 10 papers but statistical method was not mentioned (11.2%). Follow-up visits and lost information were only recorded in 2 articles, but no detailed follow-up visiting data were provided. Side effects were reported in 10 articles (11.2%). There were analysis and explanation of mixed interfering factors only in 5 papers (5.6%). There was no explanation of the evaluation of sample size in any one paper. CONCLUSION: In summary, the literature concerning clinical studies published in CJB in the past five years has become more extensive. However, the present study indicates that many clinical trials are not designed and ethical consideration is often missing. Therefore, it is deemed imperative to improve the quality of the clinical studies by improving the planning of the protocols of the study and statistical analysis of the research results in future.

Burns↗
PubMed2006

Progress of cellular dedifferentiation research.

Differentiation, the stepwise specialization of cells, and transdifferentiation, the apparent switching of one cell type into another, capture much of the stem cell spotlight. But dedifferentiation, the developmental reversal of a cell before it reinvents itself, is an important process too. In multicellular organisms, cellular dedifferentiation is the major process underlying totipotency, regeneration and formation of new stem cell lineages. In humans, dedifferentiation is often associated with carcinogenesis. The study of cellular dedifferentiation in animals, particularly early events related to cell fate-switch and determination, is limited by the lack of a suitable, convenient experimental system. The classic example of dedifferentiation is limb and tail regeneration in urodele amphibians, such as salamanders. Recently, several investigators have shown that certain mammalian cell types can be induced to dedifferentiate to progenitor cells when stimulated with the appropriate signals or materials. These discoveries open the possibility that researchers might enhance the endogenous regenerative capacity of mammals by inducing cellular dedifferentiation in vivo.

Animals↗
PubMed2006

[Analysis and evaluation of the articles concerning animal experiments published in Chinese Journal of Burns during 2000 to 2004].

OBJECTIVE: To investigate the current situation of animal experiments by analysis and evaluation of relevant articles published in the Chinese Journal of Burns during 2000 to 2004. METHODS: All articles concerning the results of animal experiments related to the treatment and medical studies in the past 5 years were analysed according to the international standard , especially in serval aspects, such as sample size, randomization method, sample choice, comparison measure, baseline comparability, estimate index, statistics method, and so oN. RESULTS: During 2000 to 2004, totally 1 116 papers were published in the journal, among them 81 papers were (accounted for 7.3% ) of all articles were reports of treatment related experiments. Out of 81 papers, in 69 experiments ( accounted for 85. 2% ) there was randomized control group, and the main problems lay in calculation of the number of samples, the application of randomization method, and analysis of statistics. CONCLUSION: Application of the randomized control modality in animal experiment is popular in our country, but the design of some studies is not so rigorous. Therefore, we should improve the design of every research project before the experiment is carried out.

Animal Experimentation↗
PubMed2005

[The effect of hyperoxic Ringer's solution on the rabbits with inhalation injury at early postburn stage].

OBJECTIVE: To investigate the effect of hyperoxic Ringer's solution on inhalation injury given at early postburn stage in rabbit. METHODS: Seventy-seven rabbits were randomly divided into four groups, i.e. A (normal control, n = 5, without injury), B (n = 24, with Ringer's solution infusion for 10 days after injury), C (n = 24, with hyperoxic Ringer's solution infusion for 10 days after injury) and D (n = 24, without treatment after injury) groups. The rabbits in B, C and D groups were observed on 1 post injury day (PID), 2 PID, 3 PID, 5 PID, 7 PID and 10 PID, with 4 in each time points. The vital signs and survival rate were observed and the blood gas analysis, the WBC and PMN in the peripheral blood, ratio of wet/dry weight (W/D) of the lung tissue, the MDA, SOD contents in the pulmonary tissue, and the pulmonary pathomorphology were determined by corresponding methods. RESULTS: The respiratory rate of the rabbits increased postburn, which was accompanied with gasping breath, flapping of nasal alae, frequent cough, and increased buccal and nasal secretion. Dry and wet rales were heard in the lungs after injury. The survival rate in D, B and C groups was 13.3%, 27.8% and 65.6%, respectively. Metabolic acidosis was identified in these groups by blood gas analysis. The indices of PaCO2, WBC, PMN, W/D, MDA in B, C and D groups were higher than those in A group in the order of D > B > C > A groups. While the pH, PaO2 value and SOD content in D group were lower than those in A group in the order of D < B < C < A groups (P < 0.05). Pathomorphological examination revealed that pulmonary volume increased after the injury with microscopic inflammatory changes in pulmonary tissue in B, C and D groups. While the extent and degree of injury in C group after the treatment of hyperoxic Ringer's solution were evidently less severe than those in other groups. CONCLUSION: Early administration of hyperoxic Ringer's solution during the early postburn stage could be beneficial to the management of inhalation injury.

Animals↗
PubMed2005

[Influence of different thawing temperature on the morphology and type I collagen metabolism of the human fibroblasts processed at - 10 degrees C in vitro].

OBJECTIVE: To explore the influence of different thawing temperatures on the morphology and type I collagen metabolism of the human fibroblasts processed at - 10 degrees C in vitro. METHODS: In vitro cultured human fibroblasts were randomly divided into control, 20 degrees C thawing, and 37 degrees C thawing groups. After being frozen at -10 degrees C, the cells in the latter two groups were thawed at 20 degrees C and 37 degrees C, respectively. The cell proliferation was assessed with MTT method and was expressed by absorption under 570nm (A ), The morphological change of the cells was observed with inverted phase contrast microscope, the change in the intracellular content of collagen was determined with immunohistochemistry, and the extracellular content of collagen was assayed with ELISA. RESULTS: In 20 degrees C thawing group, the absorbance decreased at first and increased thereafter, and they were obviously lower than that before freezing (0.95 +/- 0.16, P < 0.05 or 0.01). Cell dehydration and shrinking, cytoplasm loss and increased ratio of cytoplasm to nucleus were found in the survived fibroblasts. The cells proliferated actively at 72 and 96 hours after injury, with increased mitotic index and disordered arrangement. Compared with that before freezing (96.4 +/- 2.9) , the extracellular collagen content increased at first, decreased thereafter, and increased again slowly later (P < 0.05), while the intracellular collagen content decreased at first and increased thereafter (P < 0.05). The collagen metabolism in 37 degrees C thawing group was no difference compared with that in control group. Some cells undergone a floating period before adhering to the culture dish walls. CONCLUSION: Cell dehydration after low temperature treatment could protect the cells from damage. Proper thawing temperature could be beneficial to the cell resuscitation. Comparing with slow thawing, rapid thawing could minimize the cell damage.

Cells, Cultured↗
PubMed2004

[Experimental study on the inhibition of fibroblast contraction by alpha smooth muscle actin fusion protein].

OBJECTIVE: To investigate the influence of alpha smooth muscle actin fusion protein (alpha-SMA-FP) on fibroblast contraction, in order to find a new way to control scar contracture. METHODS: Three dimensional gel culture model of fibroblasts populated collagen lattices (FPCLs) was employed in the study. The fibroblasts were cultured in gel for 5 days. The cells in experimental group were processed by alpha-SMA-FP in dose of 5, 10, 50, 100 and 250 mg/L, respectively. The cells were therefore divided into E(1), E(2), E(3), E(4) and E(5) groups. Blank control was set to be C(1) group, and the cells processed by 250 mg/L of alpha-SMA-FP be C(2) group. The contraction rate was calculated by measuring the diameters of the gel before and after the procession. The change of contraction rate in E5 group was observed after the alpha-SMA-FP being rinsed out. Immunofluorescent staining of alpha-SMA-FP was carried out in fibroblasts. RESULTS: The contraction rate in C1 and C2 groups showed no difference, being (58.6 +/- 3.1)% and (56.2 +/- 4.9)% respectively, while that in E1 to E5 groups was (45.56 +/- 4.1)%, (42.3 +/- 4.2)%, (41.8 +/- 3.6)%, (37.6 +/- 5.8)% and (26.4 +/- 4.7)%, respectively. However, the contraction rate in E5 was (53.3 +/- 5.6)% after the alpha-SMA-FP had been rinsed out. The difference of the rates among control group and experimental groups, especially in E5 after alpha-SMA-FP being rinsed out, was significant (P < 0.05 or 0.01). alpha-SMA-FP was located on the fibers of the fibroblasts as shown by staining, while the alpha-SMA was not stained. Nevertheless, the staining was obvious in control group. CONCLUSION: alpha-SMA-FP could inhibit the contraction of fibroblasts specifically with dose dependent effect.

Actins↗
PubMed2004

[Experimental study and clinical application of composite skin grafting].

OBJECTIVE: To explore an ideal skin substitute with its appearance and texture similar to normal skin, to repair wounds with full-thickness skin defect. METHODS: Composite skin (CS) in question was composed of allo/xenogeneic acellular dermal matrix (ADM) and razor thin autoskin. One step skin grafting was employed in the experimental study and clinical trial. Razor thin autoskin alone was used as the control in the study. Changes in the antigenicity of ADM and the reformation of basement membrane (BM) structure at epidermis-dermis junction (EDJ) of ADMs were studied at designated time points after the grafting with biochemical and immunohistochemical methods. Fifty-three patients with full thickness skin defects due to various causes, including scar excision were grafted with CS, and survival rate and long-term result were observed. RESULTS: The grafted CS survived satisfactory. The reformation of the basement membrane structure was clearly observed at the 28th post-graft week. The basement membrane cells grew with polarization in an undulating arrangement. There was reformation of dermal papillae and ridges. The antigenicity of allo-ADM was obviously lower than that of xeno-ADM. Sixty-five out of 70 pieces of CS grafting (92.9%) survived totally, two of them survived partially, and three failed due to infection. The longest follow-up period was 8 and a half years. The grafted CS appeared similar to the normal skin in regard to the texture and color, especially allo-ADM, and no evident rejection reaction was seen. CONCLUSION: ADM possessed very low antigenicity, thus serving a lasting framework after grafting. In addition, it could serve as a "dermal template" for the induction of tissue regeneration.

Animals↗
PubMed2003

[An experimental study on the difference of the antigenicity of xenogenic acellular dermal matrix].

OBJECTIVE: To investigate the difference of the antigenicity of xenogenic acellular dermal matrix (ADM) implants prepared by different methods. METHODS: The split-thickness skin sheet from swine was processed by trypsin and Triton X-100 to make xeno-ADM. Twenty-five Japanese white rabbits were divided into 5 groups, i.e. xeno-ADM(1) (conjugated with glutaraldehyde), xeno-ADM(2) (conjugated with network) and xeno-ADM(3) (no conjugation, as control), in which the ADMs were and xeno-ADM(4) (conjugated) and allo-ADM (no conjugated as control), in which the ADMs were embedded into the subcutaneous place of rabbit ear and back after that the rabbits were pre-sensitized by xeno-ADM soluble protein antigen injections. The titers of anti ADMs antibody in rabbit serum were monitored during 2 - 32 post-operative weeks and the histological changes of the embedded ADMs were observed grossly and microscopically. RESULTS: The serum titers of anti-xeno-ADM in xeno-ADM(4) group was the highest. Whereas regardless of the sensitizing effects, the titers in all groups ranged as follows: xeno-ADM(3) > xeno-ADM(2) > xeno-ADM(1) (P < 0.05 - 0.01). About 40% serum samples in allo-ADM group exhibited positive anti-allo-ADM protein antibodies. Histologically, Evident and lasting inflammatory reaction could be found in the xeno-ADM grafting sites, which was much stronger than that in allo-ADM group. The degradation and absorption gradient of ADM was ranked as follow: xeno-ADM(3) > xeno-ADM(2) > xeno-ADM(4) > xeno-ADM(1) > Allo-ADM. Foreign body megalocytic reaction might evoke in the surrounding of conjugated ADM. CONCLUSION: The immunogenicity in xeno-ADM was stronger than that in allo-ADM, which could induce the host to develop immune reaction restricted by IgG. Large sheets of degenerated ADM implants could lower down the antigen-antibody reaction and ameliorate the structural destroying and degeneration absorption of ADM induced by inflammatory immune reaction.

Animals↗
PubMed2003

[Repair of contracture deformities of the patients with extremely limited donor skin at late postburn stage].

OBJECTIVE: To explore new methods to repair postburn contracture deformities in patients with extremely limited donor skin. METHODS: Five severely burned patients with extremely limited donor skin but severe deformities were enrolled in the study. The mature and the pliable scarred skin was utilized as the donor site for reconstruction of the postburn deformities. Split-thickness scarred skin was harvested for repair of postburn deformities after the scarred skin was expanded by expander, while thin razor-thin scarred skin with allo-acellular dermal matrix (ADM) was employed for the repair of postburn deformities when skin expansion was not feasible. RESULTS: All the expanded scarred skin and composite skin grafts survived completely with good function and configuration. The long-term follow-up result was satisfactory, and the grafted skin was similar to that with split-thickness skin grafting. CONCLUSION: It is feasible to employ various split-thickness scarred skin for the reconstruction of postburn deformities. This technique is a new effective procedure for the reconstruction of postburn deformities, especially for those with extreme scarcity of donor site.

Adult↗