Keisuke Morita

Rapid effects of olopatadine hydrochloride on the histamine-induced skin responses.

Olopatadine hydrochloride is one of the second‐generation nonsedating antihistamines that are used for treating allergic disorders such as urticaria, rhinitis, and atopic dermatitis. We examined the inhibitory effects of this drug on the flare and wheal responses induced by histamine iontophoresis at 30, 60, and 90 min after oral administration in a double‐blind, cross‐over, and placebo‐controlled study. Olopatadine hydrochloride significantly inhibited the histamine‐induced flare and wheal responses as early as 60 min after oral administration when compared with placebo. Significant inihibitory effects of olopatadine hydrochloride on the itch responses were seen at 90 min after administration. Thus, olopatadine hydrochloride exhibited a very rapid and potent antihistamine effect on the histamine‐induced skin responses.

Prevention of postoperative pressure ulcers by a polyurethane film patch

Dear Editor, Patients undergoing surgery are prone to develop pressure ulcers, which are a common and expensive problem, especially for university hospitals.1 In such central hospitals, surgeons perform more complicated operations that usually elongate the surgical time, thus leading to an increase in the risk of pressure ulcers.2 To prevent postoperative pressure ulcers, the use of suitable pressure-relieving instruments as well as periodic changes in the operative positioning are recommended.1 However, these are usually very difficult in complicated operations. It is known that pressures of more than 30 mmHg shut down the cutaneous arterioles and venules and that, if continued, prolonged pressure may induce local ischemia and sequential necrosis.3 In addition to the pressure and its duration, shearing forces can also play an important role in augmenting the ischemia of the affected tissue.2,4 Polyurethane film is frequently used to cover a sutured wound because of its high air permeability. Another advantage of polyurethane film is that its smooth surface decreases shearing forces. We therefore speculated that polyurethane film might lower the risk of developing pressure ulcers. We examined the incidence of pressure ulcers in 201 patients who underwent surgical operations. All of the patients had their operations in the dorsosacral position for gastrointestinal, urological and gynecological disorders. In this position, the sacral area is the most pressured site. Among the 201 patients, polyurethane films were patched at the sacral pressure sites on 98 patients. The occurrence of pressure ulcers was evaluated by observing the indurated erythema (early lesion of a pressure ulcer) at 0, 3 and 24 h after the operation. There was no significant difference in age, gender, operation time, body mass index, or preoperational pressure on the sacral area between the patients with polyurethane film application and the patients without the application (Table 1, Mann–Whitney’s U-test or χ2 test with Yates’ correction). Among the 103 patients without the polyurethane film patch, indurated erythema of the sacral area was observed in 22, 12 and four patients at 0, 3 and 24 h after operation, respectively. Among the 98 patients to whom the polyurethane film was applied, the indurated erythema was observed in 10, 6 and one cases at 0, 3 and 24 h after operation, respectively (Table 1). The polyurethane film patch significantly reduced the occurrence of pressure-induced indurated erythema of the sacral area just after operation (χ2 test with Yates’ correction; P = 0.0491). The effects of age,

Migration of keratinocytes is impaired on glycated collagen I

Advanced glycation end products are the chemical modification of proteins induced by sugars in a hyperglycemic condition. Extracellular matrix proteins are prominent targets of nonenzymatic glycation because of their slow turnover rates. The aim of this study was to investigate the influence of nonenzymatic glycation of type I collagen on the migration of keratinocytes. The migration of keratinocytes was dramatically promoted on native type I collagen‐coated dishes compared with that on uncoated dishes. When type I collagen was glycated with glycolaldehyde, large amounts of advanced glycation end products were produced; the glycated collagen I‐coated dishes did not promote the migration of keratinocytes. Glycated collagen I did not affect the proliferative capacity of keratinocytes. However, the adhesion of keratinocytes to glycated collagen I was profoundly diminished in a glycation intensity‐dependent manner. α2β1 integrin is responsible for the migration and adhesion of keratinocytes to type I collagen. Pretreatment with glycated collagen I did not affect the expression level or functional activity of α2β1 integrin on keratinocytes. These findings suggest that in the presence of glycated collagen I, keratinocytes lose their adhesive and migratory abilities. As the glycation did not modify the α2β1 integrin on keratinocytes, it is suggested that glycation may diminish the binding capacity of type I collagen.

Prevalence of atopic dermatitis and serum IgE values in nursery school children in Ishigaki Island, Okinawa, Japan

There have been many studies of the prevalence of atopic dermatitis (AD), but few population‐based epidemiologic studies measure the prevalence in Japan among children aged 5 years and younger. We examined the prevalence of AD, serum total IgE levels and specific IgE antibodies to 10 common allergens among children in Ishigaki Island, Okinawa, Japan in 2001. We also obtained information on the predictability of the U.K. Working Party diagnostic questionnaire criteria for AD in this population. Five hundred and sixty five children aged 5 years and younger were enrolled in this study with informed consent from their parents. The questionnaire of the U.K. Working Party diagnostic criteria for AD was translated into Japanese, and the parents completed the questionnaire sheet. Physical examination and blood sampling were done for all children. Thirty‐nine out of the 565 (6.9%) children were diagnosed with AD by physical examination. The total and specific IgE levels were significantly higher in the children with AD than in those without AD. High levels of total IgE were found in 33.3% of the children with AD. A specific IgE to one or more allergens was detected in 64.1% of children with AD. However, a substantial population of children without AD also had high levels of total IgE (12.7%) and a specific IgE to one or more allergens (30.2%), and the increment of total and specific IgE levels was significantly associated with age. The percentage of positive answers to the questionnaire of the U.K. Working Party diagnostic criteria for AD was significantly higher in children with AD (59.0%) than in children without AD (5.3%) (P<0.0001). Its specificity was 94.7%. The false negative rate was 41%. In conclusion, the prevalence of AD was relatively low in children in Ishigaki Island. High levels of total IgE were found in only one third of children with AD under 5 years of age. The Japanese translated form of the questionnaire of the U.K. Working Party diagnostic criteria for AD should be refined to improve its sensitivity.

Subcellular Distribution of Cytokeratin and Vimentin in Malignant Rhabdoid Tumor: Three-Dimensional Imaging with Confocal Laser Scanning Microscopy and Double Immunofluorescence

Malignant rhabdoid tumor (MRT) is a highly aggressive neoplasm that mostly occurs in childhood, characterized histologically by rhabdoid cells as shown by eosinophilic intracytoplasmic inclusions. Although it is known that rhabdoid cells co-express cytokeratin (CK) and vimentin, the distribution patterns of these two kinds of intermediate filaments and structural relationship between them are still not known. We investigated the subcellular distribution of CKs 8 and 18 and vimentin in MRT cell lines (Tm87-16, STM91-01, TTC549, and TC289) using confocal laser scanning microscopy and double immunofluorescence, in addition to ultrastructural examination. Vimentin was diffusely expressed in the cytoplasm of MRT cells, focally forming a filamentous network. In contrast, CKs 8 and 18 were partially expressed in the cytoplasm of MRT cells, forming globules or a few vague agglomerates. Three-dimensional images in TC289 cells revealed distinct distribution patterns of cytokeratin and vimentin, showing agglomerates of cytokeratins within the vimentin filament network. We conclude that these globules and agglomerates of CKs 8 and 18 correspond with the characteristic ultrastructural finding, showing cytoplasmic bundles of intermediate filaments concentrated in whorled arrays.