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To investigate the association between polymorphism of CYP17 gene and serum hormone concentrations in aged men.Eighty-three healthy men at the average age of 66.7 were divided into a66.7 group (n = 36) and a66.7 group (n = 47), and the polymorphism of CYP17 gene in the 5' promoter region was investigated by PCR using DNA from the men's peripheral blood lymphocytes. A new recognition site was created for the restriction enzyme MspA1 I by transition (T --C) in the risk allele (A2). Three genotypes A1/A1, A1/A2, A2/A2 were established, serum sex-hormone levels measured, and mean hormone concentration evaluated in each genotype and age group.No evidence was found that the testosterone (T) level, estrogen (E2) level and T/E2 ratio were associated with the genotype of CYP17 gene. There was no significant difference in T and E2 levels between the two groups, but there was a significant increase in the T/E2 ratio (P0.05).A2 allele does not increase sex hormone levels in aged men, but the T/E, ratio was higher in the66.7 group than in the66.7 group. This may be closely associated with the mechanism of benign prostate hyperplasia and prostate cancer in aged men.

Keloid is an intricate lesion that is probably regulated by many genes. In this study, the authors used the technique of complementary DNA (cDNA) microarray to analyse abnormal gene expression in keloids and normal control skins.The polymerase chain reaction (PCR) products of 8400 genes were spotted in an array on chemical-material-coated-glass plates. The DNAs were fixed on the glass plates. The total RNAs were isolated from freshly excised human keloid and normal control skins, and the mRNAs were then purified. The mRNA from both keloid and normal control skins were reversely transcribed to cDNAs, with the incorporation of fluorescent dUTP, for preparing the hybridisation probes. The mixed probes were then hybridised to the cDNA microarray. After thorough washing, the cDNA microarray was scanned for differing fluorescent signals from two types of tissues. Gene expression of tissue growth factor-beta1 (TGF-beta1) and of c-myc was detected with both RT-PCR and Northern blot hybridisation to confirm the effectiveness of cDNA microarray.Among the 8400 human genes, 402 were detected with different expression levels between keloid and normal control skins. Two hundred and fifty genes, including TGF-beta1 and c-myc, were up-regulated and 152 genes were down-regulated. Higher expressions of TGF-beta1 and c-myc in keloid were also revealed using RT-PCR and Northern blot methods.cDNA microarray analysis provides a powerful tool for investigating differential gene expression in keloid and normal control skins. Keloid is a complicated lesion with many genes involved.

To observe the changes of matrix metalloproteinase-1,2/tissue inhibitor of metalloproteinase-1,2 (MMP-1,2 and TIMP-1,2) in granulation tissue after 30% TBSA deeper partial thickness scald, and explore the regulation mechanism of MMP-2/TIMP-2 during wound healing.150 male Wistar rats were randomly divided into 5 groups as follows: (1) normal control (n = 6); (2) injured control group (n = 36): which is subdivided into postburn 3 h, 6 h, 1 d, 3 d, 7 d and 14 d groups, respectively; (3) BDM group (n = 36): intravenous injected of 400 mg 2,3-butanedione monoxime in each rat was done after anesthesia; (4) H7 group (n = 36): Each rat was intravenous injected of 0.2 mg 1-5-isoquinolinyl-sulfony-2-methylpiperazine after anesthesia; (5) anti-c-fos group (n = 36): Each rat was intravenous injected of 5 microg c-fos monoclony antibody after anesthesia. The immunohistochemistry staining technique and the reverse transcription polymerase chain reaction (RT-PCR) were used for detecting.The expression of c-fos mRNA and protein was increased from 3 to 6 hours post-burn, and then decreased. The expression of MMP-1,2/TIMP-1,2 was delayed to 3 days post-burn compared with the expression of c-fos mRNA and protein. Treatment with BDM induced to raise c-fos mRNA and protein expression. The expression of MMP-1,2/TIMP-1,2 was also increased accordingly. However, following treatment with H7 inhibited the expression of c-fos mRNA and protein, MMP-1,2/TIMP-1,2 proteins expression decreased. Exogenous c-fos antibody could inhibit endogenous c-fos protein expression and the expression of MMP-1/TIMP-1,2 decreased, but MMP-2 has no notable changes.The expression of MMP-1,2 and TIMP-1,2 has closely relation protein kinases activated signaling pathways. The expression changes of MMP-1 and TIMP-1/TIMP-2 depend on c-fos expression. Oncogenes play an important role in the change process of wound matrix degradation and remodeling.

To evaluate the effect of fibroblast growth factor-10 (FGF-10) on the secretion of transforming growth factor-alpha (TGF-alpha), platelet-derived growth factor-AB (PDGF-AB) and vascular endothelial growth factor (VEGF) by human keratinocytes.Concentrations of FGF-10 used were 4, 16, 125 and 500 ng/ml. Serum-free keratinocyte growth medium without EGF or with EGF were as negative control and positive control, respectively. Cells were cultured at 2500, 37500 cells/cm 2 in dishes in serum-free medium and supernatants were collected at 24, 48 and 72 hours. The concentrations of TGF-alpha PDGF-AB and VEGF in cell culture supernatant were measured by using TGF-alpha, PDGF-AB and VEGF enzyme linked immunoadsorbent assay (ELISA) kits, respectively and cell numbers were counted by haemocytometer.For cells cultured at low density and cells were subconfluent, TGF-alpha in each group was low and there was no significant difference among them at 24 hours. At 48 hours, both in absolute concentrations and on a per-cell basis, FGF-10 enhanced the secretion of TGF-alpha by cells cultured at low density in a dose-dependent fashion. At 72 hours, the concentrations of TGF-alpha in all dose of FGF-10 were significantly higher than that in negative control (P0.05). The production of TGF-alpha in pg/10(6) cells in 500 ng/ml FGF-10 reached statistical significance compared with negative control (P0.05). The secretion of TGF-alpha in FGF-10 were lower than that in positive control at 48 and 72 hours. For cells cuttured at 37500 cells/cm(2), the secretion of TGF-alpha stimulated by FGF-10 was similar to that when cells cuttured at lower density. PDGF-AB in each group was undetectable. When cells cuttured at high density and reached 100 percent confluent, PDGF-AB could not be detected at 24 hours. At 48 hours, both in absolute concentrations and on a per-cell basis, PDGF-AB productions in 125 and 500 ng/ml of FGF-10 were markedly greater than those of negative control at 48 and 72 hours (P0.05), and the secretion of PDGF-AB stimulated by FGF-10 was in a dose-dependent fashion. For cells cultured at low density, although the concentrations of VEGF in 16-500 ng/ml of FGF-10 were significantly higher than that in negative control (P0.05) at 72 hours, on a per-cell basis, they were not greater than that of negative control. The secretion of VEGF in positive control was greater than that of FGF-10 at 24-72 hours.The effect of FGF-10 on increasing secretion of TGF-alpha and PDGF-AB might mediate the actions of FGF-10 on keratinocytes, fibroblasts and endothelial cells to promote re-epithelialization as well as granulation tissue deposition during wound healing.

To investigate the expression and location of epidermal growth factor (EGF) and its receptor (EGFR) in dermal chronic ulcers and normal skin in order to explore their influence on ulcer formation.The expression intensity and distribution of EGF and EGFR were detected with pathological method and immunohistochemistry method in 8 cases of dermal ulcers, 8 cases of edge of ulcer and 8 cases of normal skin.The Positive signals of EGF could be found in epidermal cells, endothelial cells and some fibroblasts; EGFR was principally located in the cytoplasm and cellular membrane of these cells mentioned above in normal skin. From normal skin, edge of ulcer to ulcerative tissues, the protein contents of EGF and EGFR were decreased progressively. In ulcerative tissues, EGF was mostly distributed in monocytes and macrophages while EGFR was chiefly sited in monocytes. When compared with normal skins, the protein expression of EGF and EGFR was notably reduced in ulcerative tissues (both P0.01). The positive cellular ratios of two proteins were reduced to (7.1+/-5.2) % and (8.8+/-5.5) % of those in normal skin respectively (all P0.01).The formation of dermal chronic ulcers is closely associated with the reduction of EGF and EGFR protein expression which may lead to binding obstruction between EGF and its receptor.

To investigate the effect of recombinant human platelet-derived growth factor (rhPDGF-BB) on cutaneous incisal wound healing in diabetic rats and this factor does-effect relationship.Thirty Wistar diabetic rats were used in this study. Four full-thickness skin wounds of 2.54 cm(2) were incised in the back of each rat. The wounds were divided into five groups: three groups were treated with different dosage of rhPDGF-BB gel (14.0 microg/cm(2) wound, 7.0 microg/cm(2) wound, 3.5 microg/cm(2) wound), other two groups were treated with vehicle or untreated, respectively. rhPDGF-BB gel was topically applied to the wounds from 1 to 14 days. The wound healing effect was assessed by the measurements of the wound area, subcutaneous chamber and histological changes of each group.On 14 days, the wounds of the three groups treated with rhPDGF-BB contracted to (0.22+/-0.30)cm(2), (0.05+/-0.06)cm(2), (0.32+/-0.32)cm(2), respectively. The area of the middle dosage groups was significantly smaller than those treated with vehicle 0.23+/-0.22 cm(2) (P0.05) and untreated (0.22+/-0.25) cm(2) (P0.05). On 7 days, the subcutaneous chambers of the three treated groups contracted to (0.04+/-0.03)ml, (0.02+/-0.02)ml, (0.06+/-0.03)ml, and there was a statistic significance when comparing middle dosage group with vehicle group (0.06+/-0.03) ml (P0.05) and untreated group (0.07+/-0.05 ml (P0.05). As for histological examination, much more granulation formation was shown in the wound bed in middle dosage group than that in other four groups on 7 days, and some of the wounds treated with middle dosage were healing on 14 days.It suggested that topical application of rhPDGF-BB might improve wound healing in diabetic rats. The effective dosage of rhPDGF-BB is 7.0 microg/cm(2) wound.

To observe the expression characteristics of EGFR and FGFR-2 in normal skin from fetal and adult, and attempted to probe the molecule mechanism of fetal scarless healing.The skin samples of fetal and adult were taken from abortive fetus of obstetrics unit and donor site of plastic operation patients in our burn unit, respectively. EGFR and FGFR-2 were used as the biochemical markers for reparative cells. Immunohistochemistry staining technique was employed to determine the expressive levels of different epithelial cells markers.There were EGFR and FGFR-2 antibody positive cells in normal skin from fetal and adult, but the expressive levels of EGFR and FGFR-2 protein had apparent difference, with the time of fetation increasing, the EGFR and FGFR-2 positive expression rate became stronger gradually. The number of FGFR-2 antibody positive cells found in adult skin was much more than that in fetal skin.There were the inherent differences of EGFR and FGFR-2 antibody immunohistochemistry staining in cells of adult and fetal skin. which may be an essential facet of fetal scarless healing.

To study the effects of delayed resuscitation on the apoptosis rate (ap%) and expression of apoptosis-related genes of lamina propria lymphocytes (LPL), intra-epithelial lymphocyte(IEL) after burn in rats.Thirty Wistar rats were randomly divided into early resuscitation (ER) and delayed resuscitation (DR) groups, 24 rats of them were subjected to 30% total body surface area (TBSA) III degree scald burn on back, among which 12 received fluid resuscitation immediately, and 12 with delayed fluid resuscitation. Six rats were subjected to sham burn served as control. DNA fragmentation, DNA agarose gel electrophoresis were used to observe the apoptosis of LPL and IEL. Reverse transcription-polymerase chain reaction (RT-PCR) was employed to detect the expression of interleukin-1beta-converting enzyme (ICE) and B cell lymphoma-2 (bcl-2).The ap% of LPL and IEL increased significantly after burn (all P0.01). The ap% in DR group was higher than in ER group at 12 hours postburn. Distinct DNA "ladders" were visualized in agarose gel electrophoresis 6 hours postburn for both LPL and IEL. The expression of ICE gene increased dramatically after burn, and it expressed higher in DR group than that in ER group postburn (P0.05 or P0.01). A strong expression of bcl-2 in LPL and IEL were detected before burn, but the expressions decreased significantly after burn and delayed resuscitation (P0.05 or P0.01).The apoptosis of LPL and IEL increased significantly after burn and delayed resuscitation. The unbalanced expression of apoptosis-enhanced gene ICE and apoptosis-inhibited gene bcl-2 may be responsible for the dramatically increased apoptosis of LPL and IEL postburn.

To investigate the different location and the expression characteristics of epidermal stem cells in normal adult skin and scar tissue.Skin tissue specimens were harvested from the corresponding sites from 6 healthy volunteers and from scar tissue of 6 patients 1 year after major deep burn. beta1 integrin and keratin 19 (K19) were employed as the biochemical markers for stem cells and transit amplifying cells identification and keratin 14 (K14) and keratin 10 (K10) as markers for post-mitotic cells and terminally differentiated cells respectively. Integrin and keratin were determined by Elivision two-step immunohistochemistry.The expression of beta1 integrin and the K19 positive cell count in the epithelial basal layers of scar tissue were evidently decreased and weakened than those in normal adult healthy skin. Furthermore, the positive cells expressing K14 in epidermis of scar tissue were only located in 2 - 3 layers of basal epidermis, and their number was much less than that in normal adult skin. Whereas the cells positively expressing K10 were distributed wider in area than that in normal healthy skin. The epidermal stem cells and transit amplifying cells in scar epidermis were much less in number than that in normal skin. The differentiation process of scar epidermal stem cells was different from that of normal skin. And the proportions of post-mitotic cells and terminally differentiated cells were abnormal.The results indicated that the self-renewal ability of the scar epidermis was decreased, and the differentiation process of it was in disorder, which may be a reason for the abnormality of structure and function of the epidermis in scar, and a reason for the decreased ability of wound healing of scar tissue.

To observe the differences in protein contents of three transforming growth factor-beta (TGF-beta) isoforms, beta 1, beta 2, beta 3 and their receptor(I) in hypertrophic scar and normal skin and to explore their influence on scar formation.Eight cases of hypertrophic scar and their corresponding normal skin were detected to compare the expression and distribution of TGF-beta 1, beta 2, beta 3 and receptor(I) with immunohistochemistry and common pathological methods.Positive signals of TGF-beta 1, beta 2, and beta 3 could all be detected in normal skin, mainly in the cytoplasm and extracellular matrix of epidermal cells; in addition, those factors could also be found in interfollicular keratinocytes and sweat gland cells; and the positive particles of TGF-beta R(I) were mostly located in the membrane of keratinocytes and some fibroblasts. In hypertrophic scar, TGF-beta 1 and beta 3 could be detected in epidermal basal cells; TGF-beta 2 chiefly distributed in epidermal cells and some fibroblast cells; the protein contents of TGF-beta 1 and beta 3 were significantly lower than that of normal skin, while the change of TGF-beta 2 content was undistinguished when compared with normal skin. In two kinds of tissues, the distribution and the content of TGF-beta R(I) had no obviously difference.The different expression and distribution of TGF-beta 1, beta 2 and beta 3 between hypertrophic scar and normal skin may be associated with the mechanism controlling scar formation, in which the role of the TGF-beta R (I) and downstream signal factors need to be further studied.

To explore the possible mechanisms of skin regeneration through the epidermal stem cells stimulated by epidermal growth factor (EGF).At 8 and 14 days after treatment with EGF, the tissue specimens from 8 skin ulcered patients who were treated with EGF were used to evaluate the distribution and differentiation of epidermal stem cells. The expression of beta 1 integrin, keratin 19 (K19), keratin 14(K14) and keratin 10 (K10) in skin was detected with SP immunohistochemical methods. Hematoxylin and eosin staining method were used to observe the tissue structure. Another 7 biopsies from ulcered patients without EGF management were used as the control.The results from the hematoxylin and eosin staining showed that the epidermis in EGF treated wounds was thick and the epidermal ridges were enlarged both in 8 and 14 days compared with those in control skin. Immunohistochemical staining from beta 1 integrin and K 19 showed that all tissues treated with EGF were rich in epidermal stem cells both in 8 and 14 days. These stem cells were bigger in size and larger in number and localized at the base of the epidermis. In contrast, the positive expression cells of beta 1 integrin and K 19 in control group in the same time were scanty. It was found that there were some stem cell islands in epidermis treated with EGF in day 14 and absent from the control group. The expression of K14 and K10 could be observed in those terminally differentiating epidermal cells in both groups.The results indicate that the possible mechanisms of skin regeneration stimulated by EGF comes from the mitogenic effects and differentiation of skin stem cells.