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In the present work, treatment with AMP-PCP (β,γ-methyleneadenosine-5'-triphosphate - a competitive inhibitor of the extracellular ATP pool) or apyrase (an ATP-degrading enzyme) decreased the PSII operating efficiency (ΦPSII), photochemical quenching (qp), and maximum quantum efficiency of PSII photochemistry (Fv/Fm) of Arabidopsis leaves illuminated with high light intensity. Mutation of extracellular ATP receptor, DORN1, also caused decreases of ΦPSII, qp, and Fv/Fm when the leaves were exposed to high light. Either the treatment with AMP-PCP and apyrase or the mutation in DORN1 increased the salicylic acid content in the illuminated leaves. Salicylic acid deficiency in NahG transgenic mutant made the PSII photochemistry more sensitive to AMP-PCP or apyrase. These results indicate that extracellular ATP depletion can affect the PSII photochemistry, whereas salicylic acid can relieve this effect.

Set-valued information systems are generalized models of single-valued information systems. Its semantic interpretation can be classified into two categories: disjunctive and conjunctive. We focus on the former in this paper. By introducing four types of dominance relations to the disjunctive set-valued information systems, we establish a dominance-based rough sets approach, which is mainly based on the substitution of the indiscernibility relation by the dominance relations. Furthermore, we develop a new approach to sorting for objects in disjunctive set-valued ordered information systems, which is based on the dominance class of an object induced by a dominance relation. Finally, we propose criterion reductions of disjunctive set-valued ordered information systems that eliminate only those information that are not essential from the ordering of objects. The approaches show how to simplify a disjunctive set-valued ordered information system. Throughout this paper, we establish in detail the interrelationships among the four types of dominance relations, which include corresponding dominance classes, rough sets approaches, sorting for objects and criterion reductions. These results give a kind of feasible approaches to intelligent decision making in disjunctive set-valued ordered information systems.

The aim of this study was to compare the enhancement pattern of intrahepatic cholangiocarcinoma (ICC) on contrast-enhanced ultrasound (CEUS) with that on contrast-enhanced computed tomography (CECT). 40 pathologically proven ICC lesions in 40 patients were evaluated retrospectively with both CEUS and CECT. The enhancement level and pattern in the dynamic phases on both CEUS and CECT were analysed. The diagnostic results of CEUS and CECT before pathological examination were also recorded. During arterial phases, the number of lesions that appeared as (i) peripheral irregular rim-like hyperenhancement, (ii) diffuse heterogeneous hyperenhancement, (iii) diffuse homogeneous hyperenhancement and (iv) diffuse heterogeneous hypoenhancement were 19 (47.5%), 9 (22.5%), 5 (12.5%) and 7 (17.5%), respectively, on CEUS, and 22 (55.0%), 3 (7.5%), 2 (5.0%) and 13 (32.5%), respectively, on CECT (p = 0.125). In the portal phase, the number of lesions showing hyperenhancement and hypoenhancement were 1 (2.5%) and 39 (97.5%), respectively, on CEUS, and 15 (37.5%) and 25 (62.5%) on CECT (p = 0.0001). CEUS made a correct diagnosis in 32 (80.0%) lesions before pathological examination; CECT made a correct diagnosis in 27 (67.5%) lesions (p = 0.18). In conclusion, the enhancement patterns of ICC on CEUS were consistent with those on CECT in the arterial phase, whereas in the portal phase ICC faded out more obviously on CEUS than on CECT. CEUS had the same accuracy as CECT in diagnosing ICCs, and so can be used as a new modality for the characterization of ICC.

The objective of this study was to evaluate the correlation between the enhancement pattern of hepatocellular carcinoma (HCC) on contrast-enhanced ultrasound (CEUS) and tumour cellular differentiation on histopathology. 189 HCC lesions in 189 patients were retrospectively evaluated with CEUS and histopathological examination. CEUS was performed with SonoVue and contrast pulse sequencing. Histopathological diagnoses were made according to the Edmonson grading system. Significant differences were shown between the time that the HCC became hypoenhancing or remained echogenic in late phase and tumour cellular differentiation (p = 0.006; p = 0.036), but not with the time of commencement of hyperenhancing or commencement of isoenhancing in arterial phase and portal phase (p = 0.164, p = 0.113; p = 0.186, p = 0.070). The timing of HCC becoming hypoenhancing on CEUS is correlated with tumour cellular differentiation; well differentiated tumours wash out more slowly than poorly differentiated ones.

This Letter presents a novel type of integrated optical temperature sensor which is based on a single waveguide with a reflecting mirror at the rear end. The experimental results achieve a half-wave temperature of 0.14 C and an extinction ratio of 76%. The reflecting mode sensor shows advantages over the Mach-Zehnder structure in terms of high sensitivity and good extinction ratio. © 1993 John Wiley & Sons, Inc.

Exposure of prostate carcinoma cell lines to retinoids, which function through the classical retinoic acid nuclear receptor, (RARs) or retinoid X receptors (RXRs), results in minimal cytostatic inhibition of cell proliferation.Growth inhibition and various regulatory responses were investigated in two human prostate carcinoma cell lines (LNCaP and PC-3) treated with or without a synthetic retinoid, CD 437.Incubation of prostate carcinoma cell lines with a novel retinoid CD437 resulted in the marked inhibition of proliferation. LNCaP and PC-3 possessed IC50 values for CD437 of 375 nM and 550 nM, respectively. Incubation with 1 microM CD437 for 24 hr resulted in 100% and 60% inhibition of growth in LNCaP and PC-3 cells, respectively. Simultaneously, cell flow cytometric analyses revealed a dramatic increase of the cell population in S phase, in both LNCaP (from 38.6% up to 86.7%) and PC-3 (27.9% to 55.7%), and a decreased proportion of cells in G2 phase, in LNCaP (from 23.7% down to 1.2%) and PC-3 (14.9% to 2.2%), indicating a significant S-phase arrest. The cell growth inhibition and S-phase arrest in these cells were followed by apoptosis, as revealed by the acquisition of the characteristic cell morphology including the appearance of apoptotic bodies, and further confirmed by cellular DNA fragmentation. CD437-induced-S phase arrest was associated with upregulated mRNA levels of p21waf1/cip1/sdi1 in both LNCaP (p53+/+) and PC-3 (53-/-) cells.CD437 represents a unique retinoid that induces S-phase arrest and apoptosis in both androgen-dependent (LNCaP) and -independent (PC-3) human prostate cancer cells, suggesting a potential role of CD437 in the treatment of human prostate cancer.