Randomization of left-right asymmetry due to loss of nodal cilia generating leftward flow of extraembryonic fluid in mice lacking KIF3B motor protein

Microtubule-dependent motor, murine KIF3B, was disrupted by gene targeting. The null mutants did not survive beyond midgestation, exhibiting growth retardation, pericardial sac ballooning, and neural tube disorganization. Prominently, the left-right asymmetry was randomized in the heart loop and the direction of embryonic turning. lefty-2 expression was either bilateral or absent. Furthermore, the node lacked monocilia while the basal bodies were present. Immunocytochemistry revealed KIF3B localization in wild-type nodal cilia. Video microscopy showed that these cilia were motile and generated a leftward flow. These data suggest that KIF3B is essential for the left-right determination through intraciliary transportation of materials for ciliogenesis of motile primary cilia that could produce a gradient of putative morphogen along the left-right axis in the node.     

Dose-response relationship between total cadmium intake and beta 2-microglobulinuria using logistic regression analysis

Noradrenaline stimulates not only Ca2+ mobilization but also cAMP formation through activation of alpha 1-adrenoceptors in hepatocytes from mature male rats. We examined which subtype(s) of alpha 1-adrenoceptor mediate these signal transduction mechanisms. Treatment of hepatocytes with chloroethylclonidine produced a dose-dependent inhibition of noradrenaline-induced Ca2+ mobilization, involving both transient and sustained components. Chloroethylclonidine also blocked noradrenaline-induced cAMP accumulation. It was observed that prazosin was much more potent than WB4101 (2-(2,6-dimethoxy-phenoxyethyl)aminomethyl-1,4-benzodioxane) in antagonizing noradrenaline-induced Ca2+ mobilization. The same potency order was found in cAMP formation studies. Pretreatment of rats with pertussis toxin did not affect alpha 1-adrenergic responsiveness. Incubations of hepatocytes with tumor-promoting phorbol esters eliminated both Ca2+ mobilization and cAMP accumulation caused by noradrenaline. Our data suggest that in hepatocytes from mature male rats, single alpha 1B-adrenoceptors are linked to cAMP formation as well as Ca2+ mobilization.     

A study of sialylated carbohydrate antigen in patients with benign bronchopulmonary disease

We studied the levels of carbohydrate antigen (CA 19-9, SLX, CA 50, Span-1, and Dupan-2) in serum, bronchoalveolar lavage fluid, and tissue from patients with benign bronchopulmonary disease. Patients had bronchiectasis, healed pulmonary tuberculosis, pulmonary fibrosis, or other diseases. Bronchoalveolar lavage fluid levels and immunohistochemical findings for lung tissue samples, in the absence of digestive and other diseases, suggested that elevated serum sialylated Lewis(A) (CA 19-9, CA 50, and Span-1) and Lewis(X) (SLX) antigen in patients with benign broncho-pulmonary disease are due to marked production of sialylated carbohydrate antigen in respiratory bronchioles. Common features of patients with benign bronchopulmonary disease include elevated serum carbohydrate antigen levels and bronchiectasis.     

Endothelin-1-(1-31), a novel vasoactive peptide, increases [Ca2+]i in human coronary artery smooth muscle cells

We have previously found that human chymase cleaves big endothelins at the Tyr31-Gly32 bond and produces 31-amino acid long endothelins-(1-31), without any further degradation products. In this study, we investigated the effect of synthetic endothelin-1-(1-31) on the intracellular free Ca2+ concentration ([Ca2+]i) in cultured human coronary artery smooth muscle cells. Endothelin-1-(1-31) increased [Ca2+]i in a concentration-dependent manner (10(-14) to 10(-10) M). This endothelin-1-(1-31)-induced [Ca2+]i increase was not affected by phosphoramidon (N-(alpha-Rhamnopyranosyloxyhydroxyphosphinyl)-L-Leucyl-L-Tryptoph an), an inhibitor of endothelin-converting enzyme. It was, however, inhibited by 10(-10) M BQ123 (Cyclo-(-D-Trp-D-Asp(ONa)-Pro-D-Val-Leu-)), an endothelin ET(A) receptor antagonist, but not by 10(-10) M BQ788 (N-cis-2,6-dimethylpiperidinocarbonyl-L-yMeLeu-D-Trp(COOM e)-D-Nle-ONa), an endothelin ET(B) receptor antagonist. These results suggest that endothelin-1-(1-31) by itself exhibits vasoactive properties probably through endothelin ET(A) receptors. Since human chymase has been reported to play a role in atherosclerosis, endothelin-1-(1-31) may be one of the candidate substances for its cause.     

Development of distributed relaying processor with digitalfiltering of fast sampled data

In order to cope with advanced relaying techniques, a multimicroprocessor-based digital relay was developed. The main features are distributed processing among five processors, 32-b floating-point operations, digital filtering of fast sampled data, and a personal computer based testing tool. Performance tests of this digital relay showed the following characteristics: (1) the error of any relaying element (distance, overcurrent and undervoltage) was less than 1%; (2) operating time was less than 20 ms when the processing interval was 1.67 ms; and (3) a single relaying processor had a computational capacity of six-phase (ground, short×4 steps×3 phases) distance relays based on differential equations, accompanying elements, and a self-diagnosis function in every processing interval     

A Study of Contact Temperature Due to Frictional Heating of UHMWPE

Contact temperature of ultra-high molecular weight polyethylene (UHMWPE) bearing was measured by the infrared radiometric microscope. Lubricant temperature near the contact band was measured simultaneously and compared with the contact temperature. Contact temperature increases of up to 12°C in 30 min were observed under a mean contact pressure 12.7 MPa and sliding speed 50 mm/s. Young's modulus of UHMWPE was estimated as 0.5 GPa from the contact dimensions. The coefficient of friction was evaluated for variety of contact conditions and material combinations for UHMWPE, CoCrMo alloy and sapphire glass. It was confirmed that the contact stress has a large effect on the coefficient of friction and the fluid film has little effect on the coefficient of friction. Under sliding conditions, the thermal property of the moving material has a large effect on an increment of lubricant temperature.