[Influence of exogenous putrescine and cadaverine on pro-inflammatory factors in the peripheral blood of rabbits].

OBJECTIVE: To explore the influence of exogenous putrescine and cadaverine on pro-inflammatory factors in the peripheral blood of rabbits. METHODS: Forty ordinary adult New Zealand rabbits were divided into saline, necrotic tissue homogenate (NTH), putrescine, and cadaverine groups according to the random number table, with 10 rabbits in each group. Saline, NTH, 10 g/L putrescine, and 10 g/L cadaverine were respectively peritoneally injected into rabbits of corresponding group in the amount of 1 mL/kg. The blood sample in the volume of 2 mL was collected from the central artery of rabbit ears before injection and at 2, 6, 12, 24, 30, 36, 48, 60 hours post injection (PIH). Contents of TNF-α, IL-1, and IL-6 in the serum were determined with enzyme-linked immunosorbent assay. Data were processed with repeated measurement data analysis of variance and Spearman correlation analysis, and cubic model curve was applied in curve fitting for the contents of inflammatory factors. RESULTS: (1) The serum contents of TNF-α, IL-1, and IL-6 were increased in NTH, putrescine, and cadaverine groups in different degrees at most post injection time points. There was no significant change in the concentrations of the three pro-inflammatory factors in saline group, and they were significantly lower than those of the other three groups at most post injection time points (with F values from 3.49 to 13.58, P values all below 0.05). The serum contents of TNF-α, IL-1, and IL-6 in putrescine group began to increase at PIH 2, 6, and 6, which was similar to the trend of NTH group, but the changes were delayed compared with those of cadaverine group(all at PIH 2). The peak values of TNF-α, IL-1, and IL-6 in putrescine group were respectively (339 ± 36), (518 ± 44), and (265.9 ± 33.5) pg/mL, which were significantly lower than those of cadaverine group [ (476 ± 86), (539 ± 22), and (309.4 ± 27.1) pg/mL], with F values respectively 5.11, 1.90, and 5.56, P values all below 0.05. (2) The period of time in which contents of TNF-α, IL-1, and IL-6 began to increase (PIH 3-4) and the peaking time of the three pro-inflammatory cytokines (PIH 18-30) in putrescine group appeared later than those of cadaverine group (PIH 2 and 12-30). The duration of peaking time of the three pro-inflammatory cytokines in putrescine group was shorter than that of cadaverine group (PIH 18-30 vs. PIH 12-30). The increasing period and the duration of peaking time of TNF-α, IL-1, and IL-6 in putrescine group were close to those of NTH group (PIH 3-5 and 18-30). The correlation coefficient test analysis showed that the trends of changes in contents of three pro-inflammatory cytokines in putrescine group were significantly correlated with those of NTH group (r(TNF-α) = 0.933, P < 0.01; r(IL-1) = 0.967, P < 0.01; r(IL-6) = 0.950, P < 0.01). The obvious correlation between cadaverine group and NTH group was only found in the contents of IL-1 and IL-6 (r(IL-1) = 0.913, P < 0.01; r(IL-6) = 0.883, P < 0.05). CONCLUSIONS: Both exogenous putrescine and cadaverine can cause inflammatory reaction in rabbits. The trend of the inflammatory reaction induced by putrescine was similar with that by NTH, suggesting that putrescine may play a leading role in the inflammatory reaction induced by necrotic tissue decomposition.

Importin 13 serves as a potential marker for corneal epithelial progenitor cells.

Importin13 (IPO13), the newest member of importin-beta family discovered recently, is a unique nucleus-cytoplasm bidirectional transport receptor protein. In this study, IPO13 expression in human corneal tissue, limbal epithelial primary explant and clonal culture was evaluated by immunostaining and reverse-transcription polymerase chain reasgon. IPO13 function was evaluated in the corneal epithelial culture treated with IPO13 inhibitor, or fetal bovine serum (FBS)-containing Dulbecco's modified Eagle's medium (DMEM) medium by colony-forming efficiency, clone growth capacity, MTT, immunostaining, and Western blotting assay. IPO13 protein was expressed mainly in nuclei of limbal epithelial basal cells, but not in the other cell layers of limbus and full thickness of corneal epithelia. IPO13 was expressed in the majority of epithelial cells in early-stage clones and in the margin of late-stage clones. IPO13 was positively expressed in mouse TKE2 progenitor cells cultured in keratinocyte serum-free defined medium, while it became negative in FBS-containing DMEM, which promoted TKE2 cell differentiation. In the presence of IPO13 inhibitor, IPO13 expression and the proliferative capacity decreased in human limbal epithelial clones and mouse TKE2 cells, which were accompanied with the cell differentiation. In conclusion, our findings demonstrate for the first time that IPO13 is uniquely expressed by human limbal basal epithelial cells, and plays an important role in maintaining the phenotype, high proliferative potential, and less differentiation of corneal epithelial progenitor cells, suggesting that IPO13 could serve as a novel potential marker for corneal epithelial progenitor cells.

[Clinical evaluation of eschar grinding and biological dressing A for treatment of deep partial-thickness burn wound on the extremities].

OBJECTIVE: To evaluate the clinical effect of eschar grinding and wound coverage by biological dressing A in the management of deep partial-thickness burn wound on the extremities. METHODS: Seventy-three patients with deep partial-thickness burns on the extremities were divided into two groups to receive different managements. The patients in group 1 were treated with eschar grinding and wound coverage with biological dressing A, and group 2 received conventional treatment. The white blood cell count, body temperature, incidence of wound infection and wound healing time were observed. RESULTS: Compared with conventional treatment, wound management with eschar grinding and coverage by biological dressing A could increase the effective rate (29/32 vs 31/41, P<0.05), inhibit systemic inflammation and scar hypertrophy, and shorten the wound healing time (13.79-/+5.72 vs 17.08-/+8.39, P<0.01). CONCLUSION: Eschar grinding and wound coverage by biological dressing A can be effective for management of deep partial-thickness burns on the extremities, and earlier treatment with the dressing A achieves better effect.

[A case-control study on the risk factors of leukemia in mining areas of rare-earth in South Jiangxi].

OBJECTIVE: In order to explore the correlation on radioactive contamination of lanthanon to leukemia, and provide clues for the causes and prevention of leukemia in mining areas of rare-earth elements. METHODS: 1:1 matched case-control study was used. A total of 51 clinically confirmed leukemia cases, individually matched with controls from general population, were interviewed in mining areas of rare-earth in South Jiangxi from November to December, 2001. Data were analyzed, using conditional logistic regression. RESULTS: The main risk factors would include frequently drinking water from river (OR = 5.543), distance from residence to rare-earth mine and years for living in the area (OR = 3.308), exposure to organophosphorus pesticide (OR = 3.014). Tea drinking habit appeared to be a protective factor. CONCLUSIONS: Leukemia seemed to be related to environmental pollution with rare-earth elements around the residential areas and organophosphorus pesticide exposure. The protective factor of tea drinking habit seemed to be unique in this study, which called for further studies.