Malignant melanoma derived from cerebriform intradermal naevus.

We report a case of malignant melanoma (MM) derived from cerebriform intradermal naevus (CIN) in a 66-year-old Japanese man. The patient had cutis verticis gyrata (CVG) on the posterior area of the scalp at birth. He noticed a dome-shaped nodule at the centre of the CVG at 66 years of age. Histopathological examination found a nodule of MM arising within an extensive area of intradermal naevus. There was no metastasis to lymph nodes or other organs. To our knowledge, only two cases of CIN in which MM had later developed have been reported. We estimated that the incidence of melanoma from CIN including our case is 4.5% (3 of 67 reported cases), which seems to be comparable to the frequency of malignant alteration of giant pigmented naevi. This suggests that pathological examination is recommended for CVG, and once pathological diagnosis of CIN is confirmed, long clinical follow-ups are necessary for detecting development of MM.

Transcellular relocation of tetrahydrobiopterin across Caco-2 cells: a model study of tetrahydrobiopterin absorption through epithelial cells of intestinal mucosa.

Oral administration of tetrahydrobiopterin (BH(4)) has been known to be effective in treating BH(4)-deficient patients. It has long been established that BH(4) is absorbed by the intestinal mucosa. However, the mechanism for translocation of BH(4) across epithelial cells has not been elucidated. In order to study BH(4) transport mechanisms, Caco-2 cells were employed in this study as an epithelial cell model. Caco-2 cells were cultured (2 x 10(4) cells/0.3 cm(2) well) for 21 days in a 24-well format using Transwell, a porous membrane-based culture dish, at which point they had established themselves as a tight sheet with a definite polarity. When BH(4) (100 micromol/L) was given to cells from the apical side, a considerable translocation toward their basolateral side was noted. The rate of BH(4) movement was around 150 pmol/h per well. This was comparable to the highest rate of BH(4) uptake or its release so far obtained using a monolayer culture of Caco-2 cells on an ordinary plastic plate. The transcellular movement of BH(4) across the polar culture on the porous membrane was effectively prevented by benzbromarone (10 micromol/L), a well known inhibitor of a group of transporters including urate transporter (URAT1), organic anion transporters (OATs), and multidrug-resistance-associated proteins (MRPs). It was thus concluded that in Caco-2 cells, BH(4) moved across the cell interior in a rapid ligand-specific manner that was driven by a transporter.

Tetrahydrobiopterin in intestinal lumen: its absorption and secretion in the small intestine and the elimination in the large intestine.

In treating hereditary deficiency of tetrahydrobiopterin (BH(4)), supplementation with BH(4) might be the ultimate choice of therapy. Oral administration of BH(4) has been believed to be inefficient owing to poor absorption of BH(4) in the intestine. In this study, we found a considerable amount of BH(4) as well as its oxidized pterins in the ingredients of intestinal lumen of mice when they were served food that did not contain significant amounts of biopterin. Ligation of the biliary duct led to significant decrease in luminal biopterin. Supplementation of BH(4) either by intraperitoneal administration of sepiapterin or of 6RBH(4) ((6R)-L-erythro-5,6,7,8-tetrahydrobiopterin) increased the BH(4) content in the intestinal lumen with a slight delay after the rise of blood BH(4). In these mice, biopterin appeared in the large intestine, caecum and colon, 2 h after the administration. The appearance of BH(4) in the large intestine was accompanied by a large amount of pterin (2-amino-4-hydroxypteridine). The amounts of biopterin + pterin that appeared in the large intestine after intraperitoneal administration of BH(4) were not greater than those found after oral administration at the same dose. When the mice were treated with a large dose of antibiotics prior to the BH(4) administration, the amount of biopterin increased in the caecum but the amount of pterin decreased greatly. These results suggested that a large proportion of BH(4) administered moved to the large intestine, where most biopterin was decomposed presumably by enteric bacteria. Nonetheless, most of the orally administered biopterin was taken up by the small intestine and the amount of biopterin reaching the large intestine was almost the same as that which appeared after direct injection of 6RBH(4) into the peritoneal cavity.

Detection of antibodies to Japanese encephalitis virus in the wild boars in Hiroshima prefecture, Japan.

Serum specimens were collected from 25 wild boars in Hiroshima prefecture located in the western region of Japan from November 2004 to February 2005. The sera were tested for antibodies to Japanese encephalitis virus (JEV) by IgM capture and IgG enzyme-linked immunosorbent assays (ELISA), and plaque reduction neutralization test. Seventeen samples (68%) were positive for neutralizing antibody to JEV. All the neutralizing antibody-positive samples were positive for IgG-ELISA. One was also positive for IgM. The results indicate that approximately 70% of the wild boars were positive for anti-JEV antibody, and raises the possibility that wild boars may play a role in the infectious cycle of JEV in this region.

The palmar pocket method: an adjunct to the management of zone I and II fingertip amputations.

In 1979 Brent reported a new replantation method, without vascular anastomosis, that used a subcutaneous pocket. Brent chose the contralateral chest wall as a pocket site, but in other clinical reports, the abdominal wall was used. For both sites there were complications such as stiffness in the wrist, elbow, and shoulder joints and anxiety about pulling out the pocketed finger. To overcome these problems, we chose the ipsilateral palm and named this method the palmar pocket method. We used this method in 16 cases in which a digit other than the thumb had been amputated between the tip and lunula. In 13 cases the method was completely successful, and in 3 cases there was a small area of tip necrosis. The palmar pocket method is a simple and reliable operation for fingertip reattachment and more comfortable for patients than pocketing in the chest wall or abdominal wall.

Lipid utilization for ovarian development in an autogenous mosquito, Culex pipiens molestus (Diptera: Culicidae).

During the first ovarian cycle, autogenous female mosquitoes develop their ovaries in the absence of blood feeding. In autogenous Culex pipiens molestus (Forskal), complete yolk deposition was observed 2 d after emergence, even when no feeding was allowed (starved). Neutral lipids in Cx. p. molestus increased during the pupal stage, abruptly declined after emergence, and again increased on day 3. In contrast, neutral lipids decreased in anautogenous Anopheles stephensi (Liston) and Cx. p. pallens (Coquillett) and starved females died within 2-3 d after emergence. High ratios of two major neutral lipids, free fatty acid and triglyceride, were isolated by thin-layer chromatography (TLC) from the lipid contents of both Cx. p. molestus and An. stephensi fourth-instars and newly emerged females. Fatty acid analyses using gas liquid chromatography (GLC) and GLC-mass spectrometry (GLC-MS) showed higher proportions of unsaturated than saturated fatty acids in Cx. p. molestus at both stages and two major neutral lipids: free fatty acids and triglycerides. The percentage composition of linoleic acid (C18:2), which is a precursor of arachidonic acid, was higher in Cx. p. molestus than in An. stephensi. Our results indicated that elevated lipid content before emergence may play a role of inducing ovarian development in autogenous mosquitoes.

Rapid turnover of tryptophan hydroxylase is driven by proteasomes in RBL2H3 cells, a serotonin producing mast cell line.

Previously we demonstrated that tryptophan hydroxylase (TPH) undergoes very fast turnover driven by ATP-dependent proteolysis in serotonin producing mast cells [Hasegawa et al. (1995) FEBS Lett. 368, 151-154]. We searched for the major proteases involved in the rapid degradation of TPH in RBL2H3 cells. Among various protease inhibitors tested, proteasome inhibitors MG115, MG101, MG132, and lactacystin effectively inhibited the intracellular degradation of TPH. Administration of the proteasome inhibitors to cultured cells caused more than a 5-fold accumulation of TPH. Administration of the inhibitors together with cycloheximide stabilized the amount of TPH with no appreciable increase or decrease. Although MG-series proteasome inhibitors could inhibit calpain, the involvement of calpain was excluded since the cysteine protease inhibitor E-64-d, which acts on calpain, had no effect. Extracts of RBL2H3 cells were shown to contain a protease that digests TPH in an ATP-dependent manner and is sensitive to proteasome inhibitors. The ubiquitination of TPH could be visualized by Western blot analysis using both anti-TPH and anti-ubiquitin antibodies. Based on these results, we conclude that 26S proteasomes are mainly involved in the degradation of TPH. In the reported amino acid sequences of TPH from various sources including human, rabbit, rat, and mouse, a PEST sequence that is widely shared among short-lived proteins has been recognized. It was noted that the PEST sequence lies within the most conserved portion of the enzyme, the pteridine binding site.

Differences in energy metabolism and adult desiccation resistance among three Aedes (Stegomyia) species (Diptera: Culicidae) from South Sulawesi, Indonesia.

To determine the mechanisms of adult desiccation resistance of Aedes (Stegomyia) species, we estimated the carbohydrate and lipid contents of newly emerged adult mosquitoes from South Sulawesi, Indonesia. Inter- and intraspecific differences in glycogen and free fatty acid accumulation were found in Aedes aegypti (L.), Ae. albopictus (Skuse), and Ae. paullusi (Stone & Farmer). High glycogen content was determined for both sexes in all Ae. aegypti strains and in the Ujung Pandang strain of Ae. albopictus. There were no differences among species in either trehalose or sorbitol content. A trend similar to glycogen was seen for lipid content, especially the free fatty acids of neutral lipids. These energy reserves of adult mosquitoes correlated with adult desiccation survival time at 90% RH calculated by Mogi et al. (1996). In both sexes, survival time was longer in strains with high glycogen and free fatty acid content, and low trehalose content. Ae aegypti, Ae. albopictus, and Ae. paullusi are species with high, intermediate, and low levels of glycogen and free fatty acids, respectively. However, longevity of these species under desiccation conditions is associated strongly with glycogen-trehalose conversion, and free fatty acid accumulation.

Genetic differentiation among three populations of Anopheles minimus of Guangxi and Yunnan Provinces in the People's Republic of China.

Electrophoretic studies were carried out on isozymes of 3 populations of Anopheles minimus collected from Guangxi and Yunnan Provinces of the People's Republic of China in 1993. Eight proteins were analyzed by 5% polyacrylamide gel electrophoresis. The most variable population, 'Yunnan-Field' (Y-F), was highly polymorphic at 14 of 20 loci (P = 0.700) with an average heterozygosity H of 0.340. P values of 0.500 and 0.700, and H values of 0.220 and 0.210 were obtained for each from 'Guangxi-Lab' (GX-L) and 'Yunnan-Lab' (Y-L), respectively, Nei's genetic distances (D) between Y-L and GX-L, Y-F and GX-L, and Y-F and Y-L were 0.1131, 0.1946 and 0.1069, respectively. These results suggest that GX-L is distant from the 2 other populations, Y-L and Y-F, and that this genetic differentiation between the 2 populations of Yunnan and Guangxi Provinces corresponds to the forms A and B, which were morphologically classified by Xu et al (unpublished).

Genetic differentiation among three populations of Anopheles minimus of Guangxi and Yunnan Provinces in the People's Republic of China.

Electrophoretic studies were carried out on isozymes of 3 populations of Anopheles minimus collected from Guangxi and Yunnan Provinces of the People's Republic of China in 1993. Eight proteins were analyzed by 5% polyacrylamide gel electrophoresis. The most variable population, Y-F, was highly polymorphic at 14 of 20 loci (P=0.700) with an average heterozygosity H of 0.340. P values of 0.500 and 0.700, and H values of 0.220 and 0.210 were obtained for each from 'Guangxi-Lab' (GX-L) and 'Yunnan-Lab' (Y-L), respectively. Nei's genetic distances (D) between Y-L and GX-L, Y-F and GX-L, and Y-F and Y-L were 0.1131, 0.1946 and 0.1069, respectively. These results suggest that GX-L is distant from the 2 other populations, Y-L and Y-F, and that this genetic differentiation between the 2 populations of Yunnan and Guangxi Provinces corresponds to the forms A and B, which were morphologically classified by Xu et al (unpublished).

Comparative infectivity and survival of first-stage larvae of Angiostrongylus cantonensis and Angiostrongylus malaysiensis.

Angiostrongylus malaysiensis was isolated from wild rats Rattus norvegicus in a seaport area of Kitakyushu City, Kyushu, Japan in 1990. The infectivity and survival capacities of first-stage larvae of A. malaysiensis and Angiostrongylus cantonensis were compared under various conditions. Infectivity of first-stage larvae of the former in Biomphalaria glabrata was much lower than that of the latter. In an exposure at various pHs, and with various proteases and tissue homogenates of B. glabrata, the survival of first-stage larvae of A. malaysiensis was also lower than that of A. cantonensis. This lower survival was compared to that of A. cantonensis in response to desiccation of rat feces and high water temperature. First-stage larvae of A. malaysiensis thus appear to be influenced by conditions in the host's feces, specifically temperature and desiccation, and also show a greater sensitivity to pH and component proteases in the snail body than A. cantonensis.

Genetic variability in isozymes of Angiostrongylus malaysiensis.

The genetic difference between Angiostrongylus malaysiensis and A. cantonensis was assayed by electrophoretic analysis of isozymes. Six enzymes were analyzed using 5% polyacrylamide gel electrophoresis. Seven of 10 loci, namely GPI-1, GPI-2, HK-1, HK-2, MDH-1, MDH-2 and PGM-2, were shown to be polymorphic, but the remaining 3 loci, LDH, ME and PGM-1, were not. Both A. malaysiensis and A. cantonensis were polymorphic at 6 of the loci (p = 0.600) with heterozygosity H of 0.286 and 0.151, respectively. The Nei's genetic distance (D) between A. malaysiensis and A. cantonensis was 0.27470. This value indicates the level of interspecific variation within a genus. Through isozyme analysis, the present study demonstrated that A. malaysiensis of Japan is a valid species, separate from A. cantonensis.

[A five-year follow-up study on blood pressure and serum cholesterol in junior high school children].

Blood pressure and serum cholesterol changes over a five-year period were studied in 299 junior high school children (127 males and 172 females) examined during 1980-1984 in Akita Prefecture, Japan. The six factors studied were height, weight, body mass index (by Minowa's method), systolic blood pressure, diastolic blood pressure and serum cholesterol. Mean values for systolic and diastolic blood pressure increased more than 10 mmHg during the five years in both sexes. Significant positive correlations between initial and follow-up blood pressure ('tracking') were observed. The correlation coefficients for systolic blood pressure in males and in females were 0.33 and 0.28 respectively, and those for diastolic blood pressure were 0.36 in males and 0.19 in females. While there were no significant differences in serum cholesterol levels between the two periods in either sex, the correlation coefficients, which were higher than those for blood pressure, were 0.55 in males and 0.45 in females. Among the six factors at each period, significant positive correlations were observed between height and systolic blood pressure at the initial period, and between obesity and systolic blood pressure at both periods in males and females. A significant positive relationship between obesity and serum cholesterol was seen at the follow-up period in both sexes. These data suggest that a moderate degree of 'tracking' occurs in blood pressure and serum cholesterol during childhood, and that obesity is an important factor related to blood pressure and serum cholesterol.

Mechanical, electrical and cyclic nucleotide responses to peptide VIP and inhibitory nerve stimulation in rat stomach.

1. Effects of apamin on electrical and mechanical activities and cyclic nucleotide accumulation in response to vasoactive intestinal peptide (VIP) and intramural nerve stimulation were investigated in isolated circular strips of the rat stomach in the presence of atropine and guanethidine. 2. Circular muscles generated rhythmic contractions and slow waves in the antrum but not in the fundus. Intramural nerve stimulation and VIP caused frequency- and dose-dependent relaxation of fundic strips and inhibition of spontaneous contractions of antral strips. Apamin partly reduced the responses to intramural nerve stimulation but not those to VIP. 3. In the antrum, apamin reduced inhibitory junction potentials (IJPs) evoked at the nadir of slow waves but not at their zenith. In the fundus, apamin partly decreased the amplitude of IJPs. Repetitive nerve stimulation was associated with an apamin-sensitive hyperpolarization and apamin-resistant decrease in the slow wave amplitude in the antrum. 4. VIP caused a dose-dependent hyperpolarization of fundic circular muscle membrane. In the antrum, VIP inhibited spike potentials superimposed on slow waves and it decreased the slow wave amplitude in about half of the preparations. These electrical responses to VIP were resistant to apamin. 5. Intramural nerve stimulation evoked an apamin-resistant output of VIP from muscle strips, which no longer occurred after tetrodotoxin or removal of extracellular Ca2+. 6. Intramural nerve stimulation and VIP elicited apamin-resistant increases in cyclic AMP and cyclic GMP accumulations. The effects of VIP on cyclic AMP were greater than those on cyclic GMP. The effects of intramural nerve stimulation on cyclic GMP were faster in onset than those of cyclic AMP. 7. It is suggested that VIP is a neurotransmitter of the intramural inhibitory nerves concerned in the apamin-resistant relaxation of the rat stomach.