COMP-angiopoietin 1 Gene Transfer Enhances Cutaneous Wound Healing by Promoting Angiogenesis

BACKGROUND

Angiogenesis is crucial for wound healing and exogenous supplements of the angiogenic growth factors have been known to promote cutaneous wound healing. Angiopoietin (Ang) 1 is a recently discovered angiogenic factor and there have been few studies of its effect on cutaneous wound healing.

OBJECTIVE

We examined the effect of Ang 1 on cutaneous wound healing.

METHODS

Cartilage oligomeric matrix protein (COMP)-Ang 1 (Ade-COMP-Ang 1)- was intravenously injected to rats two days before surgery creating full-thickness wounds. The clinical wound healing rate and the number of vessels in the skin samples were evaluated on days 3, 7 and 14 post operation.

RESULTS

At post-operation day 3, 7 and 14, the clinical wound healing rate was 38.3%, 59.4% and 92.1%, respectively, in the Ade-COMP-Ang 1-treated group, compared with 20.5%, 47.5% and 87.3%, respectively, in the Ade-LacZ-treated group. There were significant differences in the results of day 3 and day 7 between two groups (p<0.05). Histopathologically, the number of the vessels of the Ade-COMP-Ang 1-treated group was 73.7, 94.1 and 62.7 at day 3, 7 and 14, compared with that of the Ade-LacZ-treated group, 53.5, 83.9, and 56.9. The differences in the results of the two groups were statistically significant (p<0.05).

CONCLUSION

These results indicate that Ade-COMP-Ang 1 therapy significantly accelerats wound healing by promoting angiogenesis. However, further study using Ade-COMP-Ang 1 gene therapy for chronic wounds in which the formation of new blood vessels is impaired is needed in the near future.

Expression of Toll-like receptors in verruca and molluscum contagiosum

Recent studies indicate that several Toll-like receptors (TLRs) are implicated in recognizing viral structures and instigating immune responses against viral infections. The aim of this study is to examine the expression of TLRs and proinflammatory cytokines in viral skin diseases such as verruca vulgaris (VV) and molluscum contagiosum (MC). Reverse transcription-polymerase chain reaction and immunostaining of skin samples were performed to determine the expression of specific antiviral and proinflammatory cytokines as well as 5 TLRs (TLR2, 3, 4, 7, and 9). In normal human skin, TLR2, 4, and 7 mRNA was constitutively expressed, whereas little TLR3 and 9 mRNA was detected. Compared to normal skin (NS), TLR3 and 9 mRNA was clearly expressed in VV and MC specimens. Likewise, immunohistochemistry indicated that keratinocytes in NS constitutively expressed TLR2, 4, and 7; however, TLR3 was rarely detected and TLR9 was only weakly expressed, whereas 5 TLRs were all strongly expressed on the epidermal keratinocytes of VV and MC lesions. In addition, the mRNA expression of IFN-beta and TNF-alpha was upregulated in the VV and MC samples. Immunohistochemistry indicated that IFN-beta and TNF-alpha were predominantly localized in the granular layer in the VV lesions and adjacent to the MC bodies. Our results indicated that VV and MC skin lesions expressed TLR3 and 9 in addition to IFN-beta and TNF-alpha. These viral-induced proinflammatory cytokines may play a pivotal role in cutaneous innate immune responses.

Possible role of Fas/Fas ligand-mediated apoptosis in the pathogenesis of fixed drug eruption

BACKGROUND

Although epidermal and dermal T cells play roles in the pathogenesis of fixed drug eruption (FDE), not much is known about keratinocyte death and its precise mechanism in FDE.

OBJECTIVES

Our aim is to elucidate the mechanism that underlies keratinocyte death in FDE, that is, the role of apoptosis and its signalling pathway.

METHODS

We first examined the involvement of apoptosis in the active FDE lesions by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labelling (TUNEL) assay and immunohistochemical analysis of caspase-3. We then examined the expressions of Fas and Fas ligand (FasL) to deduce the possible upstream signalling pathway of apoptosis, if apoptosis were involved. We finally characterized the infiltrated T-cell subpopulations in the active FDE lesions.

RESULTS

In the active FDE lesions, TUNEL positivity was strongly observed in the basal keratinocytes, and also weakly observed in the upper dermal infiltrates as well as in a few keratinocytes in the granular layer. The distribution of TUNEL-positive cells was similar to that of the strong staining of active capase-3. Fas was found mainly in the keratinocytes and some infiltrated dermal cells, whereas FasL was identified predominantly in the intraepidermal and dermal infiltrated cells and in some basal keratinocytes. Overlapping expression of Fas and FasL was accompanied by apoptosis in the FDE lesions. Many of the infiltrated mononuclear cells were CD8+. Perforin was rarely observed in the FDE lesions.

CONCLUSIONS

These findings suggest that apoptosis of the keratinocyte is highly likely to be involved in the pathogenesis of FDE, and this cytotoxicity might be predominantly mediated by the FasL of the infiltrating CD8+ T cells, possibly also playing an inflammatory role.

Novel fluorophores: efficient synthesis and photophysical study

[structure: see text] We have synthesized novel fluorophores by using Sonogashira reactions of 1,4-bis(dibromovinyl)benzene and 2,5-bis(dibromovinyl)thiophene with various aromatic bromides. The emission maxima of these fluorophores vary from the indigo blue to the reddish-orange region, depending on the structures of aromatic nuclei and peripheral moieties.

Diagnostic failure in colonoscopies for malignant disease

BACKGROUND

While colonoscopy has become established as more accurate than double contrast barium enema for detecting colonic polyps and cancers, as well as offering the opportunity for therapy, there are occasional instances where colonoscopy is misleading. The present study is to determine what problems occur, with a view to finding a solution.

METHODS

The records of the Colorectal Project at the Princess Alexandra Hospital indicate retrospectively that 346 patients have been correctly diagnosed with cancer of the colon and rectum by colonoscopy in the 5 years up to October 1996. During the same time eight patients (2.3%) were recorded at the same hospital as being misdiagnosed by colonoscopy, the lesion being either missed completely or misplaced.

RESULTS

In five of these patients there was failure to recognize that the whole colon had not been examined endoscopically, thereby missing a more proximal lesion. In two patients the lesion was missed although the entire colon was examined. In one patient the lesion was discovered but inaccurately sited. Six of these mistakes would have been obviated by the routine use of fluoroscopy to confirm the totality of the colonoscopy and to site any lesions found. The other two cases occurred because of failure to remember that colonic examination during withdrawal should be performed meticulously back as far as the anal canal. Failure to diagnose a colon cancer on the initial colonoscopy led to an average delay of 6 months for definitive care.

CONCLUSIONS

It is recommended that fluoroscopy be used routinely during colonoscopy to site accurately any lesions found, and to confirm the completeness of insertion if reliable landmarks, including terminal ileum, are not clearly identified.