Leukoderma induced by rhododendrol is different from leukoderma of vitiligo in pathogenesis: A novel comparative morphological study.

BACKGROUND: Rhododendrol (rhododenol), an inhibitor of tyrosinase activity, is used as a skin-whitening component. Many cases of leukoderma after the application have been reported, termed rhododenol-induced leukoderma (RIL). The aim of this study was to clarify the pathogenesis of RIL morphologically through comparison with vitiligo. METHODS: We examined 14 cases of RIL and 15 cases of vitiligo using routine histopathology and immunohistochemistry. Thirteen cases of RIL, six cases of vitiligo and specimens of the RIL mouse model were evaluated by electron microscopy. RESULTS: There were common findings in RIL and vitiligo at the light-microscopic level: (a) vacuolar changes in the dermo-epidermal junction, (b) melanophages in the papillary dermis, (c) perifollicular lymphocyte infiltration, (d) loss or decrease of basal melanin pigment and (e) decrease of melanocytes in the lesions. The ultrastructural observations showed specific findings of RIL: (a) remaining melanocytes in depigmented lesions, (b) inhomogeneous melanization in melanocytes and (c) degenerated melanosomes in melanocytes. Some of the findings were observed in a RIL mouse model. Furthermore, it is notable that cell organelles of melanocytes were intact in our RIL cases. CONCLUSION: Morphological changes of RIL targeting melanosomes in melanocytes without degeneration of organelles reflect the reversible clinical course of most cases.

Establishment of human dental epithelial cell lines expressing ameloblastin and enamelin by transfection of hTERT and cdk4 cDNAs.

BACKGROUND: An in vitro cell culture system of dental epithelium is useful for the investigations of cellular differentiation and function of ameloblast in amelogenesis and of regenerative therapy in human tooth. However, there have been no immortalized human dental epithelial ameloblastic-lineage cell lines, which proliferate indefinitely and additionally produce enamel matrix proteins. METHODS: We transfected two retroviral constructs of human telomerase reverse transcriptase (hTERT) cDNA and mouse cyclin-dependent kinase 4 (cdk4) cDNA into the primary ameloblastoma cells and isolated immortalized human dental epithelial cell lines of HAM1, HAM2 and HAM3. The three cell lines were examined by electron microscopy, assay of senescence-associated ß-galactosidase activity, mRNA expression and immuno-reactivity of dental epithelial marker cell molecules and enamel matrix proteins. RESULTS: They showed undifferentiated phenotypes in monolayer culture and did not have any ß-galactosidase activity. The transcripts of dental epithelial cell markers of Msx2, Jagged1, Notch1, Sp3, Sp6, keratin 14 and keratin 18 were confirmed. In addition, mRNA and protein expression of ameloblastin and enamelin were also detected in three cell lines. All cells in the three cell lines were keratin 14- and 18-positive and some elongated cells were Jagged1-positive. Msx2-positive nuclei were noted in only HAM2 cells. CONCLUSION: We established three cell lines by transfection of hTERT and cdk4 cDNAs, which were characterized as dental epithelial progenitor cells containing ameloblast-lineage cell phenotype.

[Clinical trials of Escherichia coli O-serogroup serodiagnosis in patients with diarrhea by Ec-LPS array].

After developing the Ec-LPS array for Escherichia coli O-serogroup serodiagnosis (J. Jpn. Infect. Dis., 2007; 81: 26-32), we tested the array's usefulness in sera bled over 8 years ago from 24 patients with pediatric diarrhea. IgM and IgA antibodies in 20 sera among sera from the 24 reacted with a single LPS spot, making it possible to diagnose the O-serogroup. IgG antibodies in almost all patient sera reacted with many LPS among the 58 O-serogroup LPS of E. coli. O-serogroup strains of E. coli isolated from the 24 patients numbered 15. Among 11 patients in who O-serogroups were serodiagnosed by both methods, 7 were diagnosed with the same O-serogroups. Based on these results, this array appears useful in the O-serogroup serodiagnosis of E. coli.

Apocrine Adenocarcinoma Occurring on the Chin.

We report a case of adenocarcinoma affecting the chin of a 48-year-old man. The tumor showed signs of apocrine differentiation and had infiltrated the muscle. The patient had no history or clinical evidence of breast cancer. We made a diagnosis of cutaneous apocrine adenocarcinoma. Apocrine adenocarcinoma rarely arises in areas with scarce apocrine glands. We reviewed the literature on apocrine adenocarcinoma of the face in areas other than the eyelids and auditory canal, where specialized apocrine glands are present.

[Serum anti-lPS antibody production in an outbreak of enterohemorrhagic Escherichia coli O157 infection among schoolchildren].

Although there have been many reports of the usefulness of serodiagnosis of enterohemorrhagic Escherichia coli (EHEC) O157, the serotype of the bacteria detected and the increase in anti-LPS antibody have not always been consistent. In this study we investigated the diagnostic significance of measurements of anti-LPS antibody by ELISA in an outbreak of O157 infection among schoolchildren in whom the bacteriological test findings were clarified and the age groups were uniform. The anti-LPS antibody titer was measured in 31 patients (77 serum samples) in an outbreak of EHEC O157 : H7 infection (220 children infected) that occurred in a primary school in Morioka in 1996. The anti-O157 LPS antibody positivity rates of IgM, IgG, and IgA were 98.7%, 85.7%, and 98.7%, respectively. Between the time the meal that caused the outbreak and 19 days later, anti-O157 LPS IgM antibody and IgA antibody were detected in all patients. The specificity was investigated using control serum, and the specificity of IgM, IgG, and IgA was 93.5%, 93.5%, and 97.2%, respectively. Some samples contained antibodies against O111 and O26 LPS, but the titers were lower than the anti-O157 antibody titer. The anti-O111 antibody titer and anti-O26 antibody titer were highly correlated, suggesting that they were crossreactive antibodies for O157 LPS. No significant correlation was found between differences in clinical manifestations and the anti-O157 LPS antibody titer in this O157 outbreak in schoolchildren. It was clarified that an increase in anti-LPS antibody was found to support the diagnosis of mild cases of 0157 infection infection as well as severe cases.

[Study on pollutant pathway of norovirus contamination in oysters].

Noroviruses (NVs) cause human gastroenteritis through person-to-person transmission and via contaminated foods. In food poisoning, a major suspected cause is the consumption of raw oysters. We detected NVs from environmental water and oysters around a closed gulf where oysters are cultivated. We collected oyster and water samples once or twice a month for 30 months from October 2001 to March 2004. We then studied monthly changes in virus occurrence and in genetic relationships among 208 NVs isolated from water and oyster samples and from the feces of children suffering from acute gastroenteritis during the same period in the same region. In the analysis of untreated water flowing into farm sewage, NVs were detected year round. In other water samples -processed sewage, river water, and seawater-, oysters, and children's feces, NVs were detected mainly in winter. A comparison of NV nucleotide sequences showed genetic diversity, but some strains predominated in certain winter seasons. These predominant strains were detected across sample materials. In 2002/03, an identical strain was detected in sewage, river water, seawater, oysters, and feces. We also found that NV genetic types changed at the beginning of the season, in November or December, in both 2001/02 and 2002/03. This study showed a clear relationship between NVs detected in children's feces and those in environmental water and oysters. These results support the idea that NVs are transmitted from the feces of infected persons to oysters by the flow of water through farm sewage, rivers, and the sea, finally accumulating in the mid-gut gland of oysters.

Augmentation effects of lymphocyte activation by antigen-presenting macrophages on FDG uptake.

OBJECTIVE: Research on FDG-uptake by blood cells has revealed that FDG is incorporated by macrophages and granulocytes, as well as activated lymphocytes. These characteristics of FDG suggest the possibility of visualizing the distribution of immunocytes in target organs. The aim of this study was to investigate if mouse spleen-derived lymphocytes, activated by macrophages presenting sheep red blood cell (sRBC) antigens, could be traced by FDG. METHODS: One percent of a sRBC suspension was injected into the peritoneal cavity of mice thereby creating immunity to the sRBC antigen. The splenocytes, consisting mostly of lymphocytes, were isolated, and serum containing the anti-sRBC antibody was mixed with sRBC to prepare sRBC-antibody complexes (sRBC-AbCs). Then five percent of a thioglycolate medium was injected into the peritoneal cavity of the same mice, and macrophages of ascitic cell origin were obtained. These macrophages were added to the sRBC-AbCs to induce sRBC antigen presenting macrophages. These were incubated with splenocytes obtained from sRBC immunized mouse (sRBC immunized splenocytes) or non-immunized splenocytes to induce a T cell immune response. [3H]deoxyglucose ([3H]DG) and FDG were incorporated in splenocytes, and the quantity of their uptake was measured. RESULTS: [3H]DG uptake by sRBC-immunized splenocytes was about eleven times as high as that of non-immunized splenocytes. In contrast, [3H]DG uptake by sRBC-immunized splenocytes, co-cultured with macrophages phagocytizing sRBC-AbCs, was about 40 times higher compared with non-immunized splenocytes. Splenocytes in non-immunized mice picked up very little [3H]DG, despite co-culture with macrophages phagocytizing sRBC-AbCs. Similar tendencies were observed with FDG. CONCLUSIONS: These results suggest that the SUV calculated in PET reflects not only the number of lymphocytes, but also the activation state of the lymphocytes themselves. In addition, the biodistribution of antigen specific lymphocytes, that have been taken up FDG in vitro and returned to the body, can be observed through PET.