EELFS as a new tool of local structural characterization of solid surfaces

A new apparatus to obtain information on local structures and chemical states of solid surfaces has been constructed, with which we measure electron energy-loss fine structures (EELFS), excited by electrons of a few keV incident at a grazing angle. We describe results about O/Ni(100) and O/W(100) systems, where we extensively take advantage of anisotropy in regard to momentum transfer of the probe electron and high surface sensitivity of this technique.     

A case of neurologic type of Wilson's disease with increased aluminum in liver: comparative study with histological findings to metal contents in the liver

Histological findings and metal contents in the liver were studied in a patient with neurologic type of Wilson's disease. Copper and aluminum contents in the biopsied liver of the patient with Wilson's disease were measured simultaneously by neutron activation analysis at Research Reactor Institute, Kyoto University. Four cases of adult cirrhosis were selected as the control for cirrhosis and five cases of adult liver as the control for neurologically normal. The biopsied liver showed markedly increase in the copper content (814.4 micrograms/g: dry weight) and extremely high content of aluminum (479.4 micrograms/g: dry weight), compared to those of the controls. On the other hand, macroscopically no cirrhosis was observed and the characteristic appearances of macronodular cirrhosis failed to detect histologically. Interestingly the fibrosis or inflammation of the liver was seen faintly. It is likely that toxic metals in the liver such as aluminum, copper and manganese might be implicated in the pathogenesis of neurologic type of Wilson's disease.     

Secure data communication protocols in bidirectional star network

The author describes a secure data communication method based on the CSMA/CD protocol in bidirectional star networks. A procedure for detecting packet collision while transmitting the jamming signal is required. The author assess two kinds of protocol, a CRV (code rule violation) protocol and a DR (delayed replying) protocol     

Infrared and raman investigations of the charge ordering phenomena in the monoclinic salts κ-(BEDT-TTF)4[M(CN)6][N(C2H5)4]·2H2O (M=CoIII, FeIII)

The monoclinic crystals of κ-phase charge-transfer salts formed by BEDT-TTF with Co(CN)₆ or Fe(CN)₆ anions undergo a phase transition at T=150 K. Temperature dependences of FT-NIR Raman spectra and IR reflectance spectra were studied. We show that the phase transition is related to a charge ordering and there exist charge fluctuations above 150 K.     

A new triple stain for Helicobacter pylori suitable for the autostainer: carbol fuchsin/Alcian blue/hematoxylin-eosin

OBJECTIVE: To develop an inexpensive stain to simultaneously visualize gastric morphology and Helicobacter pylori. METHODS: Gastric biopsies were stained with Genta stain using manual methods, and with carbol fuchsin/Alcian blue/hematoxylin-eosin using an automatic slide stainer (Sakura DRS-601). Slides were then coded and interpreted by 2 pathologists. Helicobacter pylori was scored using a visual scale (0 [none] to 5 [maximum]). RESULTS: One hundred slides were scored; H pylori was present in 64%. Carbol fuchsin/Alcian blue/hematoxylin-eosin stain gave excellent demonstration of gastric morphology. All positive cases (score > or =2) were correctly interpreted. Thirty-six slides had a score of 1 (< or =2 bacteria per entire slide). Of these, 10 were scored negative by Genta stain and 12 were scored negative by the carbol fuchsin/Alcian blue/hematoxylin-eosin stain (P = not significant). Hematoxylin-eosin was significantly less accurate than either of the other 2 stains (P < .02). CONCLUSION: The carbol fuchsin/Alcian blue/hematoxylin-eosin (El-Zimaity) stain is an economical stain suitable for simultaneous visualization of H pylori infection and gastric morphology.     

Activation of Ca(2+)-dependent K+ current by acetylcholine and histamine in a human gastric epithelial cell line

The effects of acetylcholine (ACh) and histamine (His) on the membrane potential and current were examined in JR-1 cells, a mucin-producing epithelial cell line derived from human gastric signet ring cell carcinoma. The tight-seal, whole cell clamp technique was used. The resting membrane potential, the input resistance, and the capacitance of the cells were approximately -12 mV, 1.4 G ohms, and 50 pF, respectively. Under the voltage-clamp condition, no voltage-dependent currents were evoked. ACh or His added to the bathing solution hyperpolarized the membrane by activating a time- and voltage-independent K+ current. The ACh-induced hyperpolarization and K+ current persisted, while the His response desensitized quickly (< 1 min). These effects of ACh and His were mediated predominantly by m3-muscarinic and H1-His receptors, respectively. The K+ current induced by ACh and His was inhibited by charybdotoxin, suggesting that it is a Ca(2+)-activated K+ channel current (IK.Ca). The measurement of intracellular Ca2+ ([Ca2+]i) using Indo-1 revealed that both agents increased [Ca2+]i with similar time courses as they increased IK.Ca. When EGTA in the pipette solution was increased from 0.15 to 10 mM, the induction of IK.Ca by ACh and His was abolished. Thus, both ACh and His activate IK.Ca by increasing [Ca2+]i in JR-1 cells. In the Ca(2+)-free bathing solution (0.15 mM EGTA in the pipette), ACh evoked IK.Ca transiently. Addition of Ca2+ (1.8 mM) to the bath immediately restored the sustained IK.Ca. These results suggest that the ACh response is due to at least two different mechanisms; i.e., the Ca2+ release-related initial transient activation and the Ca2+ influx-related sustained activation of IK.Ca. Probably because of desensitization, the Ca2+ influx-related component of the His response could not be identified. Intracellularly applied inositol 1,4,5-trisphosphate (IP3), with and without inositol 1,3,4,5-tetrakisphosphate (IP4), mimicked the ACh response. IP4 alone did not affect the membrane current. Under the steady effect of IP3 or IP3 plus IP4, neither ACh nor His further evoked IK.Ca. Intracellular application of heparin or of the monoclonal antibody against the IP3 receptor, mAb18A10, inhibited the ACh and His responses in a concentration-dependent fashion. Neomycin, a phospholipase C (PLC) inhibitor, also inhibited the agonist-induced response in a concentration-dependent fashion. Although neither pertussis toxin (PTX) nor N-ethylmaleimide affected the ACh or His activation of IK,Ca, GDP beta S attenuated and GTP gamma S enhanced the agonist response.(ABSTRACT TRUNCATED AT 400 WORDS)