Hiroshi Hachisuka

Epidermolysis bullosa simplex associated with muscular dystrophy: Phenotype-genotype correlations and review of the literature ☆ ☆☆ ★

BACKGROUND Epidermolysis bullosa simplex associated with muscular dystrophy (EBS-MD; OMIM# 226670) is an autosomal recessive disorder caused by genetic defects in the plectin gene. Because EBS-MD is relatively rare, and gene defects have been elucidated only in a limited number of patients, the precise phenotype-genotype correlations have not yet been fully elucidated. OBJECTIVE The purpose of this study was to define clinical features of EBS-MD and to clarify its phenotype-genotype correlations. METHODS Clinical, ultrastructural, immunohistochemical, and molecular features of 4 unrelated Japanese patients with EBS-MD were recorded. In addition, 6 cases with defined plectin gene mutations reported in the literature were reviewed. RESULTS In skin of the EBS-MD patients, the blister formation always occurs just above the hemidesmosomes, and expression of plectin is absent or markedly reduced in all cases examined. All 10 patients, including 6 cases in the literature, showed generalized blistering at birth or soon thereafter, and experienced nail deformities. In addition, decayed teeth (5 cases), urethral strictures (3), mild palmoplantar hyperkeratosis (2), infantile respiratory complications (2), alopecia (1), and laryngeal webs (1) were present. All 8 patients who were older than 9 years demonstrated considerable muscle weakness, and the majority of them ended up being wheelchair bound. Among the 10 patients, 7 were products of consanguineous marriage, 9 have premature termination codon (PTC) mutations in both alleles of the plectin gene, and 7 cases were homozygous for the mutation. One patient who is homozygous for a 2719del9 in-frame deletion mutation that resulted in elimination of 3 amino acids, QEA, could still walk at the age of 46 and showed milder clinical severity. CONCLUSION EBS-MD reveals clinical features not only characteristic of EBS and MD, but also other manifestations including urethral, dental, and respiratory complications. The majority of patients are products of consanguineous marriage and have homozygous plectin gene mutations. Whereas patients with PTC mutations in both alleles typically showed severe clinical features of EBS-MD and ended up being wheelchair bound, a homozygous patient for an in-frame deletion mutation showed positive, yet attenuated, plectin expression and milder clinical phenotype. Thus plectin immunofluorescence, combined with identification of the underlying plectin mutations, is of value in predicting the severity of the muscle involvement that occurs later in life of patients with EBS-MD.

Statistical survey of 150 cases with sporotrichosis

A survey of 150 cases with sporotrichosis seen at the Dermatological Clinic of Kurume University Hospital from February 1962 to October 1986 was reported. The proportion of cases with sporotrichosis to the total number of outpatients was 0.17%. Greater percentage of cases fell into the less than 10 years old or more than 40 years old groups. The male to female ratio was 1∶1.46, and 38 cases occurred in farmers. Geographic distribution was remarkable, especially around the Chikugo and Yabe river. Sixty-four cases showed the cutaneous lymphangitic type and 85 cases the localized cutaneous type and one case atypical type. The face and upper extremities were the most affected. The sporotrichin test was positive in 117 of 131 cases. The causative organism was demonstrated in tissue sections in 69% of the cases.

Proliferating trichilemmal cyst with spindle cell carcinoma.

We report a 58-year-old woman with proliferating trichilemmal cyst (PTC), from which a spindle cell carcinoma arose. The tumor on her scalp had been removed at another hospital. Histological examination had revealed almost typical features of PTC. However, the case showed a partial transformation to spindle cell carcinoma, and transition zones between squamous epithelium and spindle cells were present. Three months after histologic examination, the patient came to us for the treatment of recurrent tumor. Despite surgical resection, the patient died as a result of distant metastases. Histologically, the recurrent tumor was composed of only spindle-shaped tumor cells. We describe the first example of this uncommon condition.

Effect of antianaphylactic agents on substance-P induced histamine release from rat peritoneal mast cells

SummarySubstance P is known to be a potent histamine liberator for mast cells. The influence of antianaphylactic agents, disodium cromoglycate (DSCG), ketotifen, and tranilast was studied on substance-P and compound 48/80-induced histamine release from rat peritoneal mast cells. Substance-P induced histamine release was inhibited by these agents, while compound 48/80-induced histamine release was not inhibited by tranilast. Our findings suggest that these antianaphylactic agents are assumed to be effective for cutaneous diseases which might be concerned with substance P and histamine.

Hemangioblastoma of the central nervous system: nature of the stromal cells as studied by the immunoperoxidase technique.

Ten hemangioblastomas of the central nervous system were examined by an immunoperoxidase technique for glial fibrillary acidic protein (GFAP), S-100 protein, and Factor VIII-related antigen to determine the origin of the stromal cells. In seven cases scattered stromal cells were positive for GFAP, and eight cases showed variable numbers of S-100 protein-positive cells. These positive cells were present throughout the tumors. S-100 protein-positive stromal cells corresponded to GFAP-positive cells, but the former were more numerous than the latter. Staining for Factor VIII-related antigen was negative in stromal cells, except in endothelial cells lining capillaries. It was suggested that stromal cells of capillary hemangioblastomas are composed by heterogeneous cell populations.

FK506 and cyclosporin A inhibit growth factor-stimulated human keratinocyte proliferation by blocking cells in the G0/G1 phases of the cell cycle

FK506, a new immunosuppressive agent, is effective in treating patients with psoriasis. A major feature of psoriasis vulgaris is the hyperproliferation of keratinocytes together with inflammation. To determine the effect of FK506 or cyclosporin A (CsA) on the keratinocyte cell cycle, flow cytometry and the growth factor free normal human keratinocyte-arrested system were used to assess keratinocyte proliferation. FK506 and CsA inhibit keratinocyte proliferation induced by EGF, TGF-alpha or IL-6. The antiproliferative effects of FK506 and CsA directly correlated with blockade of the keratinocyte cell cycle at the G0/G1 phases. These findings might indicate that the effects of FK506 and CsA on proliferation of cultured normal human keratinocytes are probably related to direct effects on growth regulation of keratinocytes via EGF, TGF-alpha or IL-6 stimulation.

Cutaneous phaeohyphomycosis caused by Exophiala jeanselmei after renal transplantation.

A 60‐year‐old man who had had a renal transplantation developed a nodule on the dorsum of his right middle finger, which was subsequently diagnosed as cutaneous phaeohyphomycosis caused by Exophiala jeanselmei. The patient was successfully treated with 5–fluorocytosine. To our knowledge, this case is the third reported case in the world caused by this species in a postrenal transplant patient that manifested as phaeohyphomycosis.

Purification of rat cutaneous mast cells with Percoll density centrifugation

SummaryThe skin is the major site on anaphylaxis, and cutaneous mast cells have an important role in its reactions. The isolation and purification of rat cutaneous mast cells are described here. Rat abdominal skin was digested with collagenase and hyaluronidase, and centrifuged with Percoll. The buoyant density of cutaneous mast cells was high, and relatively pure mast cells were obtained. The purity of cutaneous mast cells was 7.4%±2.4% before and 50.0%±6.4% after Percoll density centrifugation; peritoneal mast cells revealed 5.8%±1.3% purity before and 61.0%±10.6% purity after the same procedure. The isolated cutaneous cells released 21.3%±3.8% histamine and the peritoneal mast cells released 55.5%±3.8% histamine upon stimulation with 10 μg/ml compound 48/80. These findings suggest that there are functional subsets of connective tissue mast cells.

Development of experimental sporotrichosis in normal and modified animals

The development of experimental sporotrichosis was examined in immunologically-disturbed mice. In the case of intracutaneous inoculation, the lesion in cyclophosphamide-treated mice enlarged strikingly up to 6 days, but at 12 days it was similar in size to that in non-treated mice. The lesion in irradiated mice developed slowly up to 12 days, but thereafter it developed promptly. In nude mice, the lesion was smallest during the development of the lesion. Histological examination showed that numerous organisms were present in the lesion of nude and irradiated mice. Intraperitoneal inoculation showed that dissemination of spores were easily induced in nude mice as compared with littermate mice. These results indicate an important role of cellular immunity in the defence mechanism of sporotrichosis.

Separation of keratinocytes by density gradient centrifugation for DNA cytofluorometry

SummaryA method for the separation of guinea pig epidermal keratinocytes, in which the Feulgen-stainable material suffers minimal damage, has been investigated. The principal stage involves trypsin treatment of the epidermal sheet, stripped from the dermis with ethylenediamine tetraacetic acid. The epidermal cells thus isolated are separated into three groups by centrifugation on a continuous colloidal silica (Percoll) density gradient. The resulting arrangement of the keratinocytes in the centrifuge tube corresponds to their arrangement in situ, with basal cells at the bottom and the more differentiated cells above. By morphological examination, it can be shown that relatively pure fractions of basal cells, spinous cells, and granular cells are obtained by this method. With respect to DNA distribution pattern, there was good agreement between that of keratinocytes separated by the microdissection-ultrasonic irradiation method, or by the chymotrypsin method as reported previously by us, and that obtained by the present method.