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Notes: Using an ultrahigh-vacuum (UHV) sputtering system, we could grow two new methods of polycrystalline silicon films. The one is as-deposited polycrystalline silicon on glass at substrate temperatures under 500 °C. The other is solid-phase-crystallization by thermal annealing of as-deposited amorphous silicon films in a UHV. As-deposited polycrystalline silicon films were oriented to (220) and grain sizes were determined from half-width of x-ray diffraction to be about 40 nm. From the deposition temperature dependence of the x-ray diffraction peak intensity, the activation energy of the crystalline growth was calculated to be about 0.6 eV. Hydrogen atoms in the sputtering gas lower the reproducibility of as-deposited poly-Si. Polycrystalline silicon films produced by thermal annealing of as-deposited amorphous silicon films at 550 °C in UHV have a (111) orientation. Field-effect mobilities of the as-deposited polycrystalline silicon film and the polycrystalline silicon film by UHV thermal annealing were 5 and 18 cm2/V s, respectively. © 1995 American Institute of Physics.

Notes: We investigated the effect of hydrogen ion shower doping on polycrystalline silicon thin-film transistors (p-Si TFTs). Hydrogen atoms were introduced to the channel region of p-Si TFTs by PH3/H2 ion shower doping of the source/drain contact. Hydrogen concentration in the channel region can be controlled by altering the gate metal thickness. Hydrogen atoms affect the TFT's threshold voltage shifts until it becomes negative, in n-type TFTs. The threshold voltage shift depends on the hydrogen content of the channel region in p-Si TFTs. This is explained by the existence of Si−3 trap states in the grain boundaries. © 1995 American Institute of Physics.

Notes: Microsome, thyroid and DNA tests on patients with generalized vitiligo vulgaris, with or without Sutton's leukoderma, show a high positive rate without thyroid diseases. A small, hut not negligible, amount of IgG and O deposits in the basement-membrane zone and Keratinocytes, has been frequently seen in these diseases by immunohistoogy and immunoelectron microscopy. This evidence strongly suggests an autoimmune character for these diseases.

Notes: The inhibition of angiotensin II (AngII) by use of angiotensin converting enzyme (ACE) inhibitor or AngII receptor blocker is effective for prevention of the progression of renal diseases including IgA nephropathy (IgAN). AngII plays a variety of biological roles via AngII receptors. Through AngII type 1 receptor (AT1R), AngII induces vasoconstriction, cellular proliferation, extracellular matrix production and fibrosis, while it leads vasodilatation, apoptosis and inhibition of cell proliferation through AngII type 2 receptor (AT2R). Recent studies showed the local production of AngII in many tissues including the heart, vessel and kidney, suggesting that local AngII may be more important than circulating AngII in tissue injury. AngII is generated from angiotensin I by ACE or ACE independent pathway, such as chymase which is a serine protease. Since chymase was shown to be synthesized 80% of AngII in human heart, chymase also may play an important role in converting to AngII in the kidney. Although it was reported that ACE was produced in renal tissue, the localization of chymase and AngII receptors is unclear in the human kidney. To research the local renin-angiotensin system in renal tissue of patients with IgAN, we localized chymase mRNA, ACE mRNA, AT1R mRNA and AT2R mRNA by in situ hybridization and investigated the relationship between the expression of these mRNAs and tissue injury. Fresh frozen sections of renal tissue from 21 patients with IgAN were examined. The sections were fixed with 4% paraformaldehyde and hybridized with the digoxigenin (DIG)-labelled oligonucleotide probes for chymase mRNA, ACE mRNA, AT1R mRNA and AT2R mRNA. Using anti-DIG antibody, immunohistochemistry was performed to visualize the DIG-labelled probe. Colour was developed by reaction with H2O2 and 3,3′diaminobenzidine/=tetrahydrochloride. As identifying the exact locations of the cells positive for chymase mRNA, ACE mRNA and AngII receptor mRNA, we stained using periodic acid-Schiff after in situ hybridization. We classified the histological grading of the glomerular and tubulointerstitial injury. Two to five glomeruli were analysed in each biopsy tissue and the degree of injury in each glomerulus was graded from 1 to 3 based on the proportion of the lesion in the sectioned areas of each glomerulus. In the tubulointerstitium, three to five fields of cortical interstitium in each section were examined under low magnification (×200). In each designated field, we determined the degree of tubular atrophy and interstitial fibrosis from grade 1 to 3. In situ hybridization showed that the signals of chymase mRNA, ACE mRNA, AT1R mRNA and AT2R mRNA were observed in mesangial cells, glomerular epithelial cells, cells of the Bowman’s capsule, cells of crescent, tubular epithelial cells and some infiltrating mononuclear cells. In the glomeruli, the percentage of cells positive for chymase mRNA, ACE mRNA, AT1R mRNA and AT2R mRNA per glomerulus decreased as the glomerular injury progressed. Chymase mRNA and ACE mRNA were diffusely expressed in the glomeruli with mild injury. The expression significantly increased in the area of mesangial cells proliferation without mesangial matrix expansion, however, it decreased as the glomerular lesion progressed. In the tubulointerstitium, the expression of chymase mRNA, ACE mRNA and AT1R mRNA positively correlated with the degree of tubulointerstitial injury. The expression of AT2R became significantly strongest in moderate injury lesions and diminished in severe lesion. All mRNAs were highly expressed in atrophic tubuli. We also examined the relation of the cells positive for chymase mRNA and ACE mRNA on serial sections. Most cells positive for chymase mRNA also stained for ACE mRNA in the glomeruli and the tubulointerstitium. In situ hybridization for AT1R mRNA and AT2R mRNA in serial sections showed that some cells produced the both mRNAs, while other cells expressed only AT1R mRNA or AT2R mRNA. In the present study, we identified that chymase, ACE and AngII receptor were synthesized in renal tissue with IgAN. Our results suggest that AngII was generated by local ACE and ACE independent pathway (chymase) and that the regulation of local renin angiotensin system in renal tissue was different between glomerulus and tubulointerstitium. Local renin angiotensin system may contribute the progression of tissue injury in IgAN.

Notes: The antigenicity of premelanosomes, which are specific organelles for melanin biosynthesis in the cytoplasm of malignant melanoma cells, has been revealed by the blastogenic responses of lymphocytes from melanoma-bearing Syrian (golden) hamsters, using the lymphocyte stimula tion assay. The lymphocytes from these hamsters have also been found to exhibit cytotoxic effects on cultured melanoma cells as shown by the microcytotoxic assay technique.

Notes: A bacterium isolated from soil as an alginate lyase producer shows characteristic morphological and taxonomical properties consistent with being classified in the genus Sphingomonas. The bacterium utilizes high molecular weight (HMW)-alginate for growth by depolymerization of the polymer with intracellular alginate lyases, which are generated from a common precursor protein through autoregulated post-translational modifications. Electron microscopic observations of the cell surface and of thin sections of cells grown on HMW-alginate revealed dynamic changes in both cell surface and membrane structures. The most remarkable change is recognized in the formation of mouth-like pits which open and close depending on the presence or absence of HMW-alginate. Enzymatic and genetic analyses of HMW-alginate incorporation processes confirmed the presence of a pit-dependent and macromolecule-specific ABC transporter system in cells of Sphingomonas species A1. This is the first description of a bacterium with a pit on the cell surface and a pit-dependent endocytosic uptake system for macromolecules.

Notes: [Auszug] Fig. 1. Tyrosinase radio-assay of Fortner's melanoma soluble fraction at various concentrations. We first obtained evidence for the presence of this substance while studying the total amount of melanin formed under low substrate conditions using varying concentrations of the soluble fraction, ...