Two hypotheses have been put forward to explain the formation of photoallergens. One is that the photosensitizer is a photohapten that binds covalently to a carrier protein via the formation of free radicals resulting from ultraviolet (UV) irradiation. Thus, photohaptens are virtually the same as ordinary haptens, except for the fact that they require UV irradiation for covalent coupling with protein. Another theory suggests that the photosensitizer is a prohapten, which is converted to the complete hapten by UV irradiation. Our study suggested that the vast majority of clinically photoallergic chemicals are photohaptens rather than prohaptens. Because of the ability of photohaptens to photobind to protein, cells are easily photomodified with a photohapten by exposure to UV. Ultraviolet A light (UVA) includes the action spectrum of this photoderivatization, because protein and cells are photocoupled with photohaptenic substances by irradiation with UVA but not with UVB. The photohapten-modified cells are capable of immunizing and eliciting in vivo immune responses and in vitro proliferation of sensitized T cells. Two major diseases are caused by photohaptens: photoallergic contact dermatitis and drug photoallergy. The former is evoked by skin application of a photohapten followed by UVA irradiation, and the latter disease is induced by oral administration of a photohapten plus UVA exposure. In these disorders, the causative photohaptens are bound to MHC class II molecules/self peptides on Langerhans cells upon exposure to UVA. These photomodified Langerhans cells sensitize and elicit antigen-specific T cells that mediate the photodermatitis.
N-isopropyl-p-I-123-Iodoamphetamine (I-123-IMP) was originally developed for the measurement of the brain blood flow. I-123-IMP is known to be incorporated into melanin-producing cells suggesting that I-123IMP is incorporated in malignant melnoma. We tested both I-123-IMP and Ga-67 citrate in 36 cases with malignant melanoma in order to compare their clinical utility in the same patients. Of the 22 primary lesions, 11 (50%) were detected by I-123-IMP scan, but only 6 (22.7%) were detected by Ga-67 citrate scan. Of the 28 metastatic lesions, 15 (53.6%) were detected by I-123-IMP scan, but only 13 (46.4%) were detected by Ga-67 citrate scan. Among the I-123-IMP scans, there were no false positive cases, but Ga-67 citrate detected post operative lesions. In conclusion, I-123 IMP has advantages in the detection of malignant melanoma in terms of sensitivity and specificity.
Stress is considered to be a major social problem, influencing mental and physical health. In the present study, the influences of stress on hair growth were studied in guinea pigs, who were subjected to overcrowding stress, which is considered to be a social stress. After 7 days of overcrowding stress, the back hair was shaved. At 1, 4 and 8 days after shaving, the lengths and diameters of regrowing hairs were measured, and they were microscopically observed. Furthermore, activities of several enzymes in homogenates of skin samples were measured before and after the stress treatment. Both the length and diameter of the hairs remarkably declined in the stress group compared with those of the control group (p<0.001). Microscopically, ringed stripes were seen in the affected hairs, indicating a qualitative deterioration of the hairs. Activities of all of sulfhydryl oxidase, alkaline phosphatase, and gamma-glutamyl transpeptidase in the back skin were significantly reduced in the stress group (p<0.01). These results suggest that social stress such as the overcrowding stress may influence growth and quality of hair.
Thirty-two patients with basal cell carcinoma (BCC) on the eyelids and canthal regions were treated by surgery in the Department of Dermatology Hiroshima University. Most lesions were located on the medial canthal region or the lower eyelid. One case on the medial portion under went a canaliculus dissection and reconstruction of the lacrimal system. However, the other ten cases on the medial portion were treated with simple excisions or skin grafts. On the other hand, 12 out of 17 cases with BCC on the lower eyelid required a full thickness resection of the eyelid for complete tumor removal and were treated by various types of surgical operations, according to the defect size. Defects less than 26% of the horizontal dimension of the lower lid was directly closed after a pentagonal wedge shaped resection. A defect with less than 28% width treated by wedge resection was closed by a combination of a direct approximation and a cheek flap. Defects with less than 35% of the lower eyelid were directly closed after lateral canthotomy. Defects between 35% and 45%width were too large for primary closure and were repaired using a switch flap from the upper eyelid. Defects with more than 46% width were reconstructed with a cheek advancement flap over a chondromucosal graft from the septal cartilage. Results of all operations were satisfactory both functionally and cosmetically. The preoperative view analysis by extended photographs coincided well with the results of the operations. Thus, such photographs are useful not only to determine the size of defect but also to decide on the surgical methods.
Thirty-two patients with onychomycosis, in whom the presence of fungal elements was confirmed by KOH preparations, were treated with local applications of 1% neticonazole hydrochloride solution (A group) or 1% butenafine hydrochloride solution (B group). The diseased parts of the nail plates were removed every two weeks for examination and treatment by abrasion with an electrically driven high-speed grinder, Mycological effects of these treatments were evaluated by three different methods: KOH direct microscopic examination ; neutral red staining ; and concomitant culture on Sabouraud’s dextrose agar. All of the patients were followed up for over six months. Two out of fifteen patients (A group) and three out of seventeen patients (B group) were completely cured by six months of treatment. The improvement rates were 73.3% (11/15; A group) and 58.8% (10/17; B group). No side effects were observed in any of them. Therefore, our result suggest this method is useful as a topical treatment for onychomycosis.
A 70-year-old-patient with hemangiosarcoma of the scalp died of pneumo-hemothorax and was autopsied. In the present paper, we reported the clinical course and the autopsy findings of the patient. Additionally, the incidence of pneumo-hemothorax in cases of hemangiosarcoma of the scalp was examined in a total of nine cases autopsied in our clinic. Pneumothorax occurred only in the cases with cavernous tumor foci in the lung, and hemothorax was observed only in the cases with somatic pleural tumor foci. In our cases, the pleural tumor foci may not have been formed by a direct invasion from lung tumor foci, and they had a very high incidence, compared to the frequency of metastatic pleural lesions with other neoplasms. We suggest that the pleural tumor foci in hemangiosarcoma of the scalp may be primary, not metastatic. The lesions could be promoted by some factor from the original tumor of the scalp.