A novel mechanism of matrix metalloproteinase-9 gene expression implies a role for keratinization.

To investigate the pathophysiological role of matrix metalloproteinase (MMP)-9 in the skin, we analyzed MMP-9 expression from human keratinocytes in culture. MMP-9 and the terminal differentiation marker involucrin were co-localized in the same keratinocytes with a high concentration of Ca(2+), a potent stimulator of differentiation. We identified the novel KRE-M9 element, further downstream to the previously reported TPA responsive element in the MMP-9 promoter, and both of these two elements were shown to be important for MMP-9 transcription and Ca(2+) induction. The concomitant upregulation of MMP-9 and involucrin transcripts was probably due to the very similar gene regulatory elements, KRE-M9 and KRE-4, in their respective promoters. These results indicate a novel mechanism of transcriptional regulation for MMP-9 in the process of keratinization, implying the probable association of apoptosis and differentiation of keratinocytes in epidermal skin tissue.

Expression of c-fos and c-Ha-ras proto-oncogenes is induced in human chronic wounds.

BACKGROUND: It is known that chronic wounds such as leg ulcers have an increased risk of malignant transformation, mainly to squamous cell carcinoma (reviewed in Reference 1). OBJECTIVES: To better understand the molecular changes responsible for this increased risk of malignant transformation, we examined the expression of c-fos and c-Ha-ras, proto-oncogenes known to be involved in cellular proliferation and transformation, in chronic wounds. RESULTS: The level of both c-fos and c-Ha-ras mRNAs, determined by in situ hybridization, were heavily induced in the basal layer of epidermis in chronic wounds when compared to normal skin and acute wounds, (originated from the edge of wounds created by Moh's surgery). Expression of both proto-oncogenes was not detected in the dermis of any groups. CONCLUSIONS: These results suggest that elevated expression of proto-oncogenes may be partly responsible for the increase susceptibility of chronic wounds to malignant transformation.

Infertility in women with pemphigus vulgaris and other autoimmune diseases.

BACKGROUND: Pemphigus vulgaris (PV) is an autoimmune disease. Autoimmune diseases may adversely affect reproductive function and could result in infertility. OBJECTIVE: Our purpose was to describe nine young women with PV and infertility. METHODS: A retrospective study was performed. Clinical characteristics, immunopathologic features, treatment, clinical course, and long-term follow-up were determined. RESULTS: Eight of nine patients were unable to become pregnant. One patient became pregnant during a period of remission. In eight of the nine patients, the cause of infertility was ovarian. Anti-sperm antibodies were present in two of the patients. CONCLUSION: Some patients with PV may have infertility. No definitive conclusion about the frequency of infertility in these patients or its relation to PV can be drawn. However, these observations indirectly demonstrate that there may be important interactions between the immune and hormonal systems.

[Digestive carcinoid tumors]. / Tumeurs carcinoïdes digestives.

Three examples of intestinal carcinoid tumours are reported. As the sign in conventional radiology are non-specific and inconstant, the computed radiographic signs are stressed. Small bowel examination showed both direct signs, intraluminal filling defects, and indirect signs with separated bowel loops, sometimes angulated and fixed. In one unusual case, all the jejunal loops were affected. On CT the specific finding was a retractile mesenteric infiltration.

[Digestive carcinoid tumors]. / Tumeurs carcinoïdes digestives.

Three examples of intestinal carcinoid tumours are reported. As the signs in conventional radiology are non-specific and inconstant, the computed radiographic signs are stressed. Small bowel examination showed both direct signs, with intraluminal filling defects, and indirect signs with separated bowel loops, sometimes angulated and fixed. In one unusual case, all the jejunal loops were affected. On CT the specific finding was a retractile mesenteric infiltration.

Subcutaneous emphysema and pneumomediastinum following dental extraction.

A case of acute subcutaneous emphysema of the lateral region of the neck is described. The patient, a 26-year-old woman, also had radiologic evidence of pneumomediastinum. She completely recovered in a few days under prophylactic antibiotherapy. In this case, subcutaneous and mediastinal emphysema was most probably due to the introduction of air into the soft tissue during dental surgery using compressed air equipment.