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The oxygen reserve index (ORi™) is a parameter used for the noninvasive evaluation of arterial partial pressure of oxygen (PaO2), specifically in the 100–200 mmHg range. We aimed to report on the impact of indocyanine green (ICG) on the ORi™. In this study, we retrospectively examined patients who underwent neurosurgery between April and July 2019 and assessed the impact of ICG on ORi™. We excluded patients who did not use ICG or who were not examined for ORi™. The dose and timing of ICG administration were determined by a neurosurgeon. The changes in ORi™ were measured for up to 30 min. We analyzed ten patients and found that the ORi™ increased to 1.00 in all of them. The median time for ORi ™ to rise to 1.00 after ICG administration was 2 min (range 1–4). After rising to 1.00, ORi ™ decreased and took 27 min to return to the pre-dose value. It is important to consider the initial rapid increase and subsequent slow decrease in ORi™ when using ICG during surgery.

The nucleus of oocytes (germinal vesicle) is unusually large and its nuclear envelope (NE) is densely packed with nuclear pore complexes (NPCs) that are stockpiled for embryonic development. We showed that breakdown of this specialized NE is mediated by an Arp2/3-nucleated F-actin ‘shell’ in starfish oocytes, in contrast to microtubule-driven tearing in mammalian fibroblasts. Here, we address the mechanism of F-actin-driven NE rupture by correlated live-cell, super-resolution and electron microscopy. We show that actin is nucleated within the lamina, sprouting filopodia-like spikes towards the nuclear membranes. These F-actin spikes protrude pore-free nuclear membranes, whereas the adjoining stretches of membrane accumulate NPCs that are associated with the still-intact lamina. Packed NPCs sort into a distinct membrane network, while breaks appear in ER-like, pore-free regions. We reveal a new function for actin-mediated membrane shaping in nuclear rupture that is likely to have implications in other contexts, such as nuclear rupture observed in cancer cells.

We present an approach to quantify drug–target engagement using in vivo fluorescence endomicroscopy, validated with in vitro measurements. Doxorubicin binding to chromatin changes the fluorescence lifetime of histone-GFP fusions that we measure in vivo at single-cell resolution using a confocal laparo/endomicroscope. We measure both intra- and inter-tumor heterogeneity in doxorubicin chromatin engagement in a model of peritoneal metastasis of ovarian cancer, revealing striking variation in the efficacy of doxorubicin–chromatin binding depending on intra-peritoneal or intravenous delivery. Further, we observe significant variations in doxorubicin–chromatin binding between different metastases in the same mouse and between different regions of the same metastasis. The quantitative nature of fluorescence lifetime imaging enables direct comparison of drug–target engagement for different drug delivery routes and between in vitro and in vivo experiments. This uncovers different rates of cell killing for the same level of doxorubicin binding in vitro and in vivo., The engagement of DNA-binding drugs to their target is difficult to study, particularly in vivo. Here the authors develop an in vivo fluorescence lifetime imaging confocal laparo/endomicroscope to show intra- and inter-tumor heterogeneity in doxorubicin binding to peritoneal metastases, which depends on the route of administration.

Solo (ARHGEF40) is a RhoA-targeting guanine nucleotide exchange factor that serves to promote stress fibers and precisely organize keratin networks. Solo binds to keratin-8/18 filaments. The interplay between Solo and keratin-8/18 filaments is crucial for tensile force–induced RhoA activation and consequent actin stress fiber reinforcement., Mechanical force–induced cytoskeletal reorganization is essential for cell and tissue remodeling and homeostasis; however, the underlying cellular mechanisms remain elusive. Solo (ARHGEF40) is a RhoA-targeting guanine nucleotide exchange factor (GEF) involved in cyclical stretch–induced human endothelial cell reorientation and convergent extension cell movement in zebrafish gastrula. In this study, we show that Solo binds to keratin-8/keratin-18 (K8/K18) intermediate filaments through multiple sites. Solo overexpression promotes the formation of thick actin stress fibers and keratin bundles, whereas knockdown of Solo, expression of a GEF-inactive mutant of Solo, or inhibition of ROCK suppresses stress fiber formation and leads to disorganized keratin networks, indicating that the Solo-RhoA-ROCK pathway serves to precisely organize keratin networks, as well as to promote stress fibers. Of importance, knockdown of Solo or K18 or overexpression of GEF-inactive or deletion mutants of Solo suppresses tensile force–induced stress fiber reinforcement. Furthermore, knockdown of Solo or K18 suppresses tensile force-induced RhoA activation. These results strongly suggest that the interplay between Solo and K8/K18 filaments plays a crucial role in tensile force–induced RhoA activation and consequent actin cytoskeletal reinforcement.

〔目的〕運動前のタウリン摂取が，運動によって生じる筋疲労に与える影響を明らかにすることとした．〔対象〕大学男子サッカー選手10名とした．〔方法〕無作為化二重盲検クロスオーバー試験にて，タウリン水，プラセボ水の2種類を摂取し，75％VO2maxでのエルゴメータによる運動と，最大努力での等速性膝伸展運動を100回行った．測定項目は，血液成分，膝伸展運動中のピークトルク，および大腿直筋の平均周波数（MPF）とした．〔結果〕タウリン水摂取群は血中MB濃度の上昇と，MPFの低下が抑制される傾向を示した．〔結語〕タウリン水摂取が運動によって生じる筋損傷を抑制する可能性があることが示唆される．, [Purpose] The purpose of this study was to investigate the effect of taurine ingestion before exercise on muscle fatigue. [Subjects] Ten male soccer players participated in this study. [Methods] This study had a double-blind crossover test design. The subjects drank taurine water or placebo water before exercise. Two types of exercise were performed: bicycle ergometer and isokinetic knee extension exercise. Muscle fatigue was evaluated using the mean power frequency (MPF) of the rectus femoris electromyogram, peak torque, and blood components. [Results] The taurine blood level of the subjects who imbibed taurine water was significantly higher than that of the subjects who drank placebo water. Furthermore, their myoglobin blood level was lower and their MPF showed a tendency to decline less than that of the placebo group. [Conclusion] These results suggest that the taurine blood level is increased by taurine intake, and that muscle fatigue due to exercise was inhibited by taurine ingestion.

The nucleus of oocytes, traditionally referred to as the germinal vesicle, is unusually large and its nuclear envelope (NE) is densely packed with nuclear pore complexes (NPCs) stockpiled for embryonic development. We have shown that breakdown of this specialized NE during meiosis of starfish oocytes is mediated by an Arp2/3-nucleated F-actin ‘shell’, in contrast to microtubule-driven tearing in somatic cells. The detailed mechanism of how the cytoskeletal forces disrupt the NE remains poorly understood in any system. Here, we address the mechanism of F-actin-driven NE rupture by using live-cell and correlated super-resolution light and electron microscopy. We show that actin is nucleated within the lamina and sprouts filopodia-like spikes towards the nuclear membranes forcing lamina and nuclear membranes apart. These F-actin spikes protrude pore-free nuclear membranes, whereas the adjoining membrane stretches accumulate packed NPCs associated with the still-intact lamin network. NPC conglomerates sort into a distinct tubular-vesicular membrane network, while breaks appear in pore-free, ER-like regions. Together, our work reveals a novel function for Arp2/3-mediated membrane shaping in NE rupture that is likely to have broad relevance in regulating NE dynamics in diverse other contexts such as nuclear rupture frequently observed in cancer cells.

To prospectively determine the feasibility of low-iodine-load and low-tube-voltage computed tomographic (CT) angiographic imaging of the kidney and to evaluate the opacification and image quality compared with moderate-iodine-load and high-iodine-load techniques.Institutional review board approval and written informed consent was obtained. One hundred thirteen consecutive patients randomly underwent three protocols for dual-phase renal CT angiographic imaging: high-iodine-load (600 mg iodine per kilogram of body weight at 120 kVp); moderate-iodine-load (400 mg iodine per kilogram of body weight at 80 kVp); and low-iodine-load (contrast agent injection initially prepared at 400 mg iodine per kilogram of body weight but stopped immediately after bolus-tracking trigger at 80 kVp) scanning. CT numbers of vessels and kidneys were measured. CT numbers and signal-to-noise ratio (SNR) were compared with one-way analysis of variance and posthoc Tukey-Kramer test and depiction of vessels and image noise, with Kruskal-Wallis test and pair-wise Mann-Whitney test with Bonferroni correction.Mean iodine weight administered was significantly reduced in order of low- (16.4 g), moderate- (23.5 g), and high-iodine-load (33.7 g) protocols (P.001). Mean CT numbers of abdominal aorta, renal artery, and renal cortex in first phase were significantly lower with high-iodine-load protocol (308, 274, and 132 HU, respectively) than with moderate- (347, 334, and 156 HU, respectively; P = .001-.006) or low-iodine-load (362, 316, and 161 HU, respectively; P = .001-.003) protocol. Mean CT number of renal vein in second phase was significantly lower with low-iodine-load protocol (223 HU) than with moderate- (299 HU; P.001) or high-iodine-load (258 HU; P = .020). Mean SNR of renal medulla in second phase was significantly lower (P = .019) with moderate-iodine-load protocol (mean SNR, 7.2) than with high-iodine-load protocol (mean SNR, 10.0). No significant difference in image quality grades was found between high-iodine-load (mean grade, 2.6-2.9), moderate-iodine-load (mean grade, 2.6-3.0), and low-iodine-load (mean grade, 2.6-2.9) protocols (P = .018-.31).Combined application of low-iodine-load, bolus tracking with saline flushing, and low-tube-voltage scanning is feasible and resulted in substantial reduction of iodine dose for renal CT angiographic imaging without compromising image quality.

To prospectively assess the effect of reduced iodine load to contrast enhancement, image quality, and detectability of hepatocellular carcinomas (HCCs) in hepatic CT with a combination of 80 kVp tube voltage setting and adaptive statistical iterative reconstruction (ASIR) technique in patients with chronic liver disease.This HIPAA-compliant study was approved by our institutional review board and written informed consent was obtained in all patients. During a recent 9-month period, 170 consecutive patients (114 men and 56 women; age range, 40-85 years; mean, 67.7 years) with suspected chronic liver diseases were randomized into three CT groups according to the following iodine-load and tube-voltage protocols: 600 milligram per kilogram body weight (mg/kg) iodine load and 120 peak kilovolt (kVp) tube voltage setting (600-120 group), 500 mg/kg and 80 kVp (500-80 group), and 400mg/kg and 80 kVp (400-80 group). Analysis of variance was conducted to evaluate differences in CT number, background noise, signal-to-noise ratio (SNR), effective dose, HCC-to-liver contrast-to-noise ratio (CNR), and figure of merit (FOM). Sensitivity, specificity, and area under the receiver-operating-characteristic curve (AUC) were compared to assess the detectability of HCCs.Vascular and hepatic enhancement in the 400-80 and 500-80 groups was comparable to or greater than that in the 600-120 group (P.05). Subjective image quality was comparable among the three groups. Sensitivity, specificity, and AUC for detecting HCCs were comparable among the groups. The effective dose was kept low (3.3-4.1 mSv) in all three groups.Iodine load can be reduced by 33% in CT of the liver with a combination of 80 kVp tube voltage setting and ASIR technique, without compromising the contrast enhancement, image quality, and detection of HCCs.

To determine the optimal iodine mass (IM) to achieve a 50-HU increase in hepatic attenuation for the detection of liver metastasis based on total body weight (TBW) or body surface area (BSA) at 80-kVp computed tomography (CT) imaging of the liver. One-hundred and fifty patients who underwent contrast-enhanced CT at 80-kVp were randomised into three groups: 0.5 gI/kg, 0.4 gI/kg and 0.3 gI/kg. Portal venous phase images were evaluated for hepatic parenchymal enhancement (∆HU) and visualisation of liver metastasis. Iodine mass per BSA (gI/m2) calculated in individual patients were evaluated. Mean ∆HU for the 0.5 gI/kg group (84.2 HU) was higher than in the 0.4 gI/kg (66.1 HU) and 0.3 gI/kg (53.7 HU) groups (P

The purpose of this study was to prospectively evaluate the contrast enhancement, vascular depiction, image quality, and radiation dose of low-tube-voltage whole-body CT angiography (CTA) performed with low-concentration iodinated contrast material.Whole-body CTA was performed on 109 patients with a 64-MDCT scanner. Patients were randomized into three groups: CTA with 240-mg/mL contrast material at 80 kVp (240-80 group), 300-mg/mL at 80 kVp (300-80 group), and 370-mg/mL at 120 kVp (370-120 group). Signal-to-noise ratio (SNR), arterial depiction, image quality, and radiation dose were assessed. Figure of merit was computed to normalize signal-to-noise ratio, estimated effective dose, and iodine weight.In the 240-80 group, the mean load of administered iodine was 21.6 g; for the 300-80 group, 26.8 g; and the 370-120 group, 34.0 g (p0.05). The ranges of mean vascular enhancement were 508-521 HU, 546-593 HU, and 435-442 HU (p0.05). Arterial depiction and image quality were comparable for the 240-80 and 370-120 groups and were greater for the 300-80 group than the other two groups in selected arteries (p0.05). Effective dose was higher (p0.05) in the 370-120 group (2.8-5.4 mSv) than in the others (2.3-4.3 mSv). The figure of merit in the 240-80 group was greater than (p0.05) or comparable to that in the 370-120 group.Use of 240-mg/mL contrast material at 80 kVp seems appropriate for routine whole-body CTA and beneficial for reduction of iodine load and radiation dose, whereas use of 300-mg/mL contrast material may marginally improve delineation of selected small arteries.

PURPOSE To prospectively assess the contrast enhancement, image quality, radiation dose, and detectability of malignant pancreatic tumors with pancreatic computed tomography (CT) obtained at an 80-kilovolt (peak) (kV[p]) tube voltage setting and reduced iodine dose. METHODS Institutional review board approval and written informed consent were obtained. During a recent 10-month period, 136 patients (66 men and 70 women; age range, 21-86 years; mean ± SD age, 65.9 ± 11.0 years) with suspected pancreatic disease were randomized into 3 groups according to the following iodine-load and tube-voltage protocols: 600 mg of iodine per kilogram body weight (mg/kg) and 120 kV(p) (600-120 group), 500 mg/kg and 80 kV(p) (500-80 group), and 400 mg/kg and 80 kV(p) (400-80 group). Analysis of variance was conducted to evaluate differences in CT number, background noise, signal-to-noise ratio, effective dose, lesion-to-pancreas contrast-to-noise ratio, and figure of merit. Sensitivity, specificity, and area under the receiver-operating-characteristic curve were compared to assess the detectability of malignant pancreatic tumors. RESULTS The signal-to-noise ratios in vessels were greater (P < 0.05) in the 400-80 and 500-80 groups than in the 600-120 group, and those in pancreas were comparable between the 400-80 and 600-120 groups. No significant difference was found in effective dose, image quality, lesion-to-pancreas contrast-to-noise ratio, or figure of merit between the groups. Sensitivity, specificity, and area under the receiver-operating-characteristic curve for detecting malignant pancreatic tumors were comparable between the groups. CONCLUSIONS Pancreatic CT with an 80-kV(p) setting and 400-mg iodine per kilogram contrast material load facilitates the reduction of iodine dose while maintaining image quality and the detectability of malignant pancreatic tumors.

Rationale and Objectives To determine the recommended iodine dose of contrast material (CM) for hepatic arterial–dominant phase (HAP) and hepatic parenchymal phase (HPP) imaging to assess hypervascular hepatocellular carcinoma (HCC). Materials and Methods This was a prospective study including 348 patients with hypervascular HCC in 77 hospitals as a postmarketing surveillance to investigate the effects of body weight–tailored dose of CM (300 mgI/mL of iohexol) for hepatic multiphasic contrast-enhanced multidetector-row computed tomography imaging. Informed consent was obtained from all patients who were enrolled. The tumor-to-liver contrast (TLC) of HAP images was assessed qualitatively (QL-TLC) and quantitatively (QT-TLC [HU]; computed tomography [CT] value of tumor–CT value of hepatic parenchyma). Minimal and sufficient QT-TLC were defined as CT values corresponding to the median and 75% of QL-TLC assigned with “good,” respectively. The recommended iodine dose was estimated by the relationship between iodine dose (mgI/kg) and QT-TLC. Results There was a good correlation between QL-TLC and QT-TLC. The recommended iodine dose of CM for HAP imaging was considered to be in the range of 567–647 mgI/kg based on minimal (33.7 HU) and sufficient QT-TLC (40.9 HU). Meanwhile, the recommended dose of CM for HPP imaging was 572 mgI/kg as a dose that gives hepatic enhancement more than 50 HU during HPP imaging. Conclusions The recommended iodine dose of CM for HAP and HPP imaging may be different, being 567–647 mgI/kg and 572 mgI/kg, respectively, in assessing hypervascular HCC.

Lifespan extension has been demonstrated in dwarfism mouse models relative to their wild-type. The spontaneous dwarf rat (SDR) was isolated from a closed colony of Sprague-Dawley (SD) rats. Growth hormone deficiencies have been indicated to be responsible for dwarfism in SDR. Survival time, the markers of oxidative stress, antioxidant enzymes, and resistance to hyperoxia were compared between SDR and SD rats, to investigate whether SDR, a dwarfism rat model, also extends lifespan and has an enhanced resistance to oxidative stress. SDRs lived 38% longer than SD rats on average. This is the first report to show that dwarf rats exhibit lifespan extensions similar to Ames and Snell mice. Decreased 8-oxo-2'-deoxyguanosine (8-oxodG) content, a marker of oxidative DNA damage, indicated suppressed oxidative stress in the liver, kidney, and lung of SDRs. Increased glutathione peroxidase enzyme activity was consistent with decreased 8-oxodG content in the same tissues. The heart and brain showed a similar tendency, but this was not significant. However, the catalase and superoxide dismutase enzyme activities of SDRs were not different from those of SD rats in any tissue. This was not what the original null hypothesis predicted. SDRs had potent resistance to the toxicity associated with high O2 (85%) exposure. The mean survival time in SDRs was more than 147% that of SD rats with 168h O2 exposure. These results suggest that the enhanced resistance to oxidative stress of SDRs associated with enhanced hydrogen peroxide elimination may support its potential role in lifespan extension.

Purpose: We evaluated the relationship between internal thoracic artery (ITA) stenosis anastomosed to the left anterior descending artery (LAD) and the degree of LAD stenosis using 320-detector row computed tomography (320-ADCT) and adenosine thallium-201 myocardial perfusion scintigraphy (Tl-201-MPS).Methods: We included 101 patients who underwent coronary artery bypass grafting (CABG) using ITA grafts; 320-ADCT and adenosine Tl-201-MPS were performed 2–3 months after CABG. Clinical parameters, degree of LAD stenosis, and regional myocardial ischemia of the LAD territory were compared between patients without ITA stenosis (Group A) and with ITA stenosis (Group B). Results: Thirty patients (30%) had ≤75% LAD stenosis, and 9 patients (30%) showed significant ITA stenosis. Regional ischemia was noted in 23 patients (23%). There were no differences in clinical parameters between the 2 groups. Twenty-two patients (24%) in Group A and 8 patients (89%) in Group B had ≤75% LAD stenosis (P

To determine the optimal iodine dose for aortic and hepatic enhancement at MDCT by comparing lean body weight (LBW) with total body weight (TBW).This study was approved by our institutional review committee. One hundred and thirty-six patients were randomized into four groups: 550, 650, 750 mg iodine/(kg of LBW) and 600 mgI/(kg of TBW). The aortic and hepatic contrast enhancements (Δ HUs) during the portal venous-phase and variances of ΔHUs were compared.Mean ΔHUs for 550, 650, 750 mgI/kg LBW and 600 mgI/kg TBW were: 95.1, 109.9, 122.4, and 131.2HU, respectively, for the aorta. For the liver, 43.1, 55.4, 60.8, and 63.5 HU. Mean Δ HUs increased with iodine dose per kg LBW (p0.01), but no significant difference between 750 mgI/kg LBW and 600 mgI/kg TBW groups. Hepatic enhancement increased by ≥50 HU in 94% of patients with 750 mg/kg LBW. Variance of hepatic enhancement was marginally greater in the 600 mgI/kg TBW than in the 550 and 750 mgI/kg LBW.Hepatic enhancement variation was reduced with iodine doses based on LBW. Iodine dose of 750 mg iodine/kg LBW was appropriate to achieve hepatic enhancement≥50 HU in 94% of patients.

The cytidine analogue 5-azacytidine (azaC), which causes DNA demethylation, induced flowering in the long-day plant Silene armeria and the short-day plant Perilla frutescens var. crispa under non-inductive photoperiodic conditions, suggesting that the expression of photoperiodic flowering-related genes is regulated by DNA methylation. The progeny of plants induced to flower by azaC did not flower under non-inductive photoperiodic conditions. The DNA gel blot hybridization analysis revealed no differences in the methylation states of genomic DNA from the azaC and control progeny in P. frutescens. These results suggest that the flowering-related genes activated by DNA demethylation were remethylated in the progeny. This remethylation system may allow the genes to be demethylated in response to inductive photoperiodic conditions in each generation. The azaC treatment also induced dwarfism in P. frutescens, and this characteristic was inherited by the progeny. Similar relationships between the azaC-induced dwarfism and the demethylation/remethylation system could not be established. Genome-wide methylation changes were examined by methylation-sensitive amplified fragment length polymorphism (MS-AFLP) analysis in P. frutescens, and the results showed that the DNA methylation state was altered by photoperiodic conditions.

The purpose of this study was to compare observer interpreted steady-state coherent coronal images and gadolinium-enhanced axial images in terms of the detection and grading of esophageal varices. Magnetic resonance imaging (MRI) and gastrointestinal endoscopy were performed within 2 weeks in 90 patients with chronic liver damage, including 55 with untreated esophageal varices, for periodic screening purposes. Two blinded readers retrospectively reviewed T1- and T2-weighted images with gadolinium-enhanced (gadolinium image set) and steady-state coherent (coherent image set) images. Sensitivity for the detection of esophageal varices was higher (P

To correlate hepatic hemangioma enhancement types in gadolinium-enhanced magnetic resonance (MR) images with diffusion-weighted MR findings and apparent diffusion coefficients (ADCs).Respiratory-triggered diffusion-weighted MR images (TR/TE, 2422/46 ms; parallel imaging factor, 2; b factor, 500 s/mm(2); number of averaging, 6) obtained in 35 patients with 44 hepatic hemangiomas diagnosed by gadolinium-enhanced MR and by follow-up imaging were retrospectively evaluated. Hemangiomas were classified into three enhancement types based on gadolinium-enhanced MR imaging findings: type I, early-enhancement type; type II, peripheral nodular enhancement type; type III, delayed enhancement type. Two blinded readers qualitatively assessed lesion sizes and signal intensities on T2-weighted turbo spin-echo and diffusion-weighted images. The ADCs of hemangiomas were also measured.No significant difference was observed between the three enhancement types in terms of signal intensities on T2-weighted images. Signal intensities on diffusion-weighted images were lower in the order type I to III (P.01), and mean ADCs were 2.18 x 10(-3), 1.86 x 10(-3), and 1.71 x 10(-3) mm(2)/s for types I, II, and III, respectively (P.01). No correlation was found between lesion sizes and ADCs.Hepatic hemangiomas were found to have enhancement type dependent signal intensities and ADCs on diffusion-weighted MR images. Further studies will have to substantiate that these diffusion patterns might reflect intratumoral blood flow or perfusion.

The authors describe the MRI findings, including diffusion-weighted imaging findings, of histopathologically proven uterine carcinosarcoma in four postmenopausal women. In three of four patients, diffusion-weighted images clearly revealed hypointense areas corresponding to hypocellular regions caused by intratumoral necrosis, and apparent diffusion coefficient (ADC) mapping images indicated that necrotic areas had high ADC values. In the remaining patient, diffusion-weighted and ADC mapping images clearly distinguished components of adenocarcinoma from sarcoma. In all patients, diffusion-weighted and ADC mapping images precisely reflected histopathological findings. Diffusion-weighted images were found to demonstrate complicated tissue components in carcinosarcomas of the uterus, and thus, which may be useful for the diagnosis of this disease.

In hepatocellular carcinomas (HCCs), T1 shortening occurs due to internal protein, fat, copper, iron, hypercellularity, or a combination thereof. T1-weighted magnetic resonance imaging (MRI) is obtained with a non-fat-suppressed phase shift [in- (4 ms) and opposed- (2 ms) phase] gradient-echo sequence. Internal fat deposition is often (36%) seen in well-differentiated HCCs between 1.1 and 1.5 cm in size. T2-weighted MRI is crucial in differentiating HCCs from premalignant or borderline lesions in cirrhosis and serves as a tie breaker for small early-enhancing lesions. Gadolinium-enhanced MRI has advantages over contrast-enhanced CT: greater contrast enhancement, smaller volume of contrast, and less frequent adverse reactions. Double hepatic arterial-phase imaging has been performed in many centers, allowing less frequent off-timing arterial-phase imaging and improved temporary resolution. Hypervascular HCCs often show ‘corona’ enhancement in the late hepatic arterial phase, which makes it possible to distinguish small HCCs from enhancing pseudolesions. Liposoluble gadolinium chelate (e.g., Gd-EOB-DTPA) behaving both as an extracellular and hepatobiliary agent is very useful in the diagnosis. Diffusion-weighted imaging has become a routine imaging tool thanks to the parallel imaging technique. However, diffusion-weighted imaging may not significantly improve detection, characterization, or estimation of tumor grade for HCCs, and it should still be supplementary. In summary, we believe MRI outperforms CT in the diagnosis of HCCs.

Aim: To evaluate the significance of the expression of vascular endothelial growth factor (VEGF), its correlation with clinicopathological variables were studied in the tissue of hepatocellular carcinoma (HCC) and surrounding liver. Methods: In 56 samples (tumor and non-tumor liver tissue) collected from 28 patients, VEGF expression was examined by immunohistochemistry and western blot analysis. Results: The value of VEGF expression by western blotting was correlated with immunohistochemical staining grade. In tumor tissue, the value of VEGF expression correlated with tumor size (P = 0.034), a-fetoprotein (P = 0.036) and protein induced by vitamin K absence-II by simple regression, and histological grade (P = 0.0132) by the unpaired t-test. The level of VEGF expression in non-tumor liver was found to correlate with the value of serum albumin (P = 0.008), cholinesterase (P = 0.012) and prothrombin activity (P = 0.046). The frequency of simple nodular type in gross appearance decreased in cases with high tumor/non-tumor (T/N) ratio (P = 0.022), and the degree of portal vein invasion progressed with an increase in the T/N ratio (P = 0.008). The T/N ratio was significantly higher in early recurrence cases (P = 0.0081). Conclusion: This study on the expression of VEGF might be useful to estimate the liver condition and the clinicopathological features of HCC.

The purpose of this study was to determine whether prospective adaptive navigator correction improves slice position invariability while maintaining image quality and enables efficient cine display observation on gadolinium-enhanced multiphasic thin-slice 3D MRI of the liver.The study consisted of two parts: a phantom study and a clinical study. To explore the effect of navigator correction, a phantom was imaged in the resting state and in continuous movement. In the clinical study, gadolinium-enhanced four-phase 3D spoiled turbo field-echo images (3-mm thickness with no intersectional gap, 60 slices for whole liver) were retrospectively assessed. The subjects were 83 patients with 130 focal hepatic lesions randomized into two groups: with (n = 45) and without (n = 38) navigator correction. Images were qualitatively assessed by two blinded radiologists using a three-point slice position invariability scale for liver and focal hepatic lesions. Image degradation due to motion or artifacts was qualitatively assessed.Phantom images were obtained with excellent slice position invariability while image quality was maintained with navigator correction. Navigator correction substantially degraded the quality of the images of two patients (one with a large amount of ascites and the other with a large hepatic cyst). In the other 81 patients, the degree of slice position invariability for the liver was greater (p0.001) with (score, 2.84 +/- 0.43 [SD]) than without (score, 2.37 +/- 0.75) navigator correction. For focal hepatic lesions, slice position invariability also was greater (p0.0001) with (score, 2.95 +/- 0.21) than without (score, 2.18 +/- 0.88) navigator correction. No difference in degree of image degradation was found with or without navigator correction.Prospective navigator correction improves slice position invariability for cine display observation while preserving image quality for gadolinium-enhanced multiphasic thin-slice 3D MRI of the liver.

A novel strategy to fabricate the copper pattem by electroless copper plating was investigated. The photolithographic negative pattems were fabricated by the hybrid f11ms with the palladium nanoparticles. The palladium nanoparticles in photo-cured acrylate thin films were an effective catalyst for the electroless copper plating, and it was easily to form the catalysis flne patterns by UV irradiation and development. Addition of silica nanoparticles to the hybrid thin fllms enhanced the performance of catalyst for the electroless copper plating and adhesion between the thin f11m and deposited copper.

Previous studies have shown that pyrrhocoricin, a proline-rich antimicrobial peptide (PrAMP), killed sensitive species in a dose-dependent manner by specifically binding to DnaK. Here, on the basis of the finding that DnaK-deficient Escherichia coli strains are susceptible to PrAMPs, we used pyrrhocoricin to investigate internal targets other than DnaK. Using conventional antibiotics (bleomycin, streptomycin, and fosfomycin) that have known modes of action, first, we validated the availability of an assay using a cell-free rapid translation system (RTS), which is an in vitro protein synthesis system based on E. coli lysate, for evaluating inhibition of protein synthesis. We found that, similarly to bleomycin and streptomycin, pyrrhocoricin inhibited GFP synthesis in RTS in a concentration-dependent manner. In addition, blockage of transcription and translation steps in RTS was individually estimated using RT-PCR after gene expression to determine mRNA products and using sodium dodecyl sulfate-polyacrylamide gel electrophoresis to determine the amounts of GFP expressed from purified mRNA, respectively. The results demonstrated that this inhibition of GFP synthesis by pyrrhocoricin did not occur at the transcription step but rather at the translation step, in a manner similar to that of GFP synthesis by streptomycin, an inhibitor of the translation step by causing misreading of tRNA. These results suggest that RTS is a powerful assay system for determining if antimicrobial peptides inhibit protein synthesis and its transcription and/or translation steps. This is the first study to have shown that pyrrhocoricin inhibited protein synthesis by specifically repressing the translation step.

Stem cell therapy appears to be promising for restoring damaged or irreparable lung tissue. However, establishing a simple and reproducible protocol for preparing lung progenitor populations is difficult because the molecular basis for alveolar epithelial cell differentiation is not fully understood. We investigated anin vitrosystem to analyze the regulatory mechanisms of alveolus-specific gene expression using a human alveolar epithelial type II (ATII) cell line, A549. After cloning A549 subpopulations, each clone was classified into five groups according to cell morphology and marker gene expression. Two clones (B7 and H12) were further analyzed. Under serum-free culture conditions,surfactant protein C(SPC), an ATII marker, was upregulated in both H12 and B7.Aquaporin 5(AQP5), an ATI marker, was upregulated in H12 and significantly induced in B7. When the RAS/MAPK pathway was inhibited,SPCandthyroid transcription factor-1(TTF-1) expression levels were enhanced. After treatment with dexamethasone (DEX), 8-bromoadenosine 3′5′-cyclic monophosphate (8-Br-cAMP), 3-isobutyl-1-methylxanthine (IBMX), and keratinocyte growth factor (KGF),surfactant protein BandTTF-1expression levels were enhanced. We found that A549-derived clones have plasticity in gene expression of alveolar epithelial differentiation markers and could be useful in studying ATII maintenance and differentiation.

The radiologic diagnosis of liver metastasis involves detection, characterization, and tumor staging. Knowledge of the histopathologic changes that occur with metastases provides the best approach to the accurate interpretation of radiologic imaging findings, and in particular, radiologists need to choose appropriate imaging methods based on such knowledge. Because the majority of metastases are hypovascular, the merits of the routine acquisition of hepatic arterial dominant-phase images by contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI) are disputable. Hepatic arterial dominant-phase images may be obtained when hypervascular tumors are suspected or three-dimensional CT angiography is necessary. And, imaging during the portal venous phase is essential for detecting metastases, evaluating intrahepatic vessel invasion, and for assessing intratumoral necrosis or fibrosis. Equilibrium- to delayed-phase imaging 3-5 min after contrast administration may improve the detection of intratumoral fibrosis, and occasionally lead to more accurate tissue characterization. MRI offers diagnostic information on vascularity, amount of free water, hemorrhage, fibrosis, necrosis, and water molecule diffusion in metastases. And, liver-specific contrast agents like superparamagnetic iron oxide, liposoluble gadolinium chelate, and manganese may improve the MRI-based diagnosis of liver metastases.

We characterized the effects of in vitro cellular aging on constituents of lipid rafts in human diploid fibroblasts, TIG-1. Cholesterol recovery from lipid rafts of senescent cells was decreased by the detaching treatment, while the decrease was far less obvious in young cells. A probe that binds selectively to cholesterol in lipid rafts revealed that the amount of lipid rafts on the cell surface decreased in senescent cells upon cell detachment. Accompanying this change was the release of the raft-associated molecules caveolin and Fyn from lipid rafts upon cell detachment, suggesting a detachment-associated disorganization of lipid rafts in senescent cells. In addition, our observations showing differential sensitivities of lipid rafts from young and senescent cells to detaching treatment indicate a caution in how to detach cells. Particular attention needs to be paid to interpreting the results when lipid rafts are prepared from mechanically detached cells under detergent-free conditions.

Under Lewis acidic conditions, tris(acetylacetonato)cobalt( Co(acac)3) reacted with ethoxymethylenemalononitrile ( ETMN), analogous derivatives and general aliphatic nitriles to give a new type of β-imino–cobalt(III) complexes. A possible mechanism for this reaction is proposed. In the case of ethyl acetocyanoacetate, an acylated γ-acetylimino–cobalt(III) complex was isolated. The structure of the complex was explained supporting the proposed mechanism. The crystal structures of several complexes were determined by X-ray diffraction. One of the complexes showed prominent crystal dichroic properties in the first absorption band region. Benzoyl cyanide and phthalonitrile did not react with Co(acac)3 under the same conditions.

The purpose of our study was to assess the correlation between the intensity and characteristics of contrast enhancement on angiographically assisted CT and the intensity of vascular endothelial growth factor (VEGF) expression in hepatocellular carcinoma (HCC) and in the surrounding nontumorous liver.The intensity of VEGF expression in HCC and in the surrounding liver was expressed as a VEGF expression index by Western blot analysis in 20 surgical specimens resected in 20 patients between March 2000 and August 2002. Findings on CT during arterial portography (n = 20) and CT hepatic arteriography (n = 17) were retrospectively evaluated to determine contrast enhancement indexes and the enhancement characteristics of HCCs and of the surrounding liver. Contrast enhancement indexes and VEGF expression indexes were correlated using a simple regression test, and enhancement characteristics and VEGF expression indexes were correlated using the Spearman's rank correlation test.On CT hepatic arteriography, the contrast enhancement indexes of HCCs showed moderate inverse correlation with the VEGF expression indexes of HCCs (r = -0.57, p = 0.017) and high inverse correlation with the differences between the VEGF expression indexes of HCCs and those of livers (difference in the VEGF expression index, -0.80; p = 0.0001). The contrast enhancement index of the liver showed marginal moderate direct correlation with the VEGF expression index of the liver (0.44, p = 0.076) and high inverse correlation with the difference in the VEGF expression index (-0.71, p = 0.0013). On CT during arterial portography, the contrast enhancement indexes of HCCs showed moderate inverse correlation with the difference in the VEGF expression index (-0.51, p = 0.023). The qualitative degree of heterogeneity of hepatic artery enhancement in HCC on CT hepatic arteriography showed moderate direct correlation with the VEGF expression indexes of HCCs (0.55, p = 0.033) and high direct correlation with the difference in the VEGF expression indexes (0.73, p = 0.004).Our results indicated that the intensity and heterogeneity of hepatic artery enhancement of HCCs on CT hepatic arteriography correlated with the degree of VEGF expression in HCCs.

トリメチルアンモニウム基を含有するアクリルアミドゲルを合成し, その界面活性剤水溶液中での膨潤挙動と内部状態との関係について検討した. 陽イオン性界面活性剤水溶液中では, ゲル内の界面活性剤濃度は外液の濃度よりも低かったのに対して, 陰イオン性界面活性剤中においては, ゲル中の界面活性剤濃度は外液中の濃度よりも高くなった. また, ドデシル硫酸ナトリウム水溶液中に浸したゲルを純水に浸すと, さらに収縮した. アンモニウム基とスルホ基を併せもつ両性イオン性ゲルでは, アンモニウム基がスルホ基よりも過剰な場合に, アンモニウム基のみを含むゲルと類似の膨潤挙動を示した. これらの結果から, ゲルに界面活性剤が対イオンとして取込まれたときゲルが収縮すること, 高濃度水溶液中では過剰な界面活性剤の取込みが起こり, そのときに体積増加が見られることが明らかになった.

In the Multiphasic Health Check-up System, medical laboratory testing has been changing lately to utilize a small and compact type of testing systems. The system uses heparinized blood for chemistry tests to reduce laboratory's workload and sample volume. The dana-paroid, a mixture of glycosamino-glycans (Heparan sulfate), has been used clinically for treatment of patients with disseminated intravascular coagulopathy instead of heparin sulfate. Heparin has been used for routine laboratory tests, although it has a strong activity of platelet aggregation. This study aimed to examine availability of Danaparoid for routine hematology tests as a substitute of heparin. Although Danaparoid induced platelet aggregation directly, the reaction was weaker than that of heparin. The platelet count of Danaparoid blood was decreased after five minutes of mixing. Addition of MgSO4 or of kanamycin sulfate to Danaparoid blood was able to prevent this decrease. When Danaparoid blood was applied to chemistry tests, major chemistry test data showed acceptable results, although level differences were observed slightly. It was concluded that Danaparoid would be a good candidate for a universal anticoagulant for both chemical and hematological laboratory tests.

Novel ruthenium(II) polypyridyl complexes with diethynylphenanthrolines containing acetylthiophenyl unit(s) have been prepared and characterized by photophysical measurements. These complexes showe...

To investigate the optimal imaging delays for hepatic arterial and portal venous phases of gadolinium-enhanced dynamic spoiled gradient-recalled-echo magnetic resonance (MR) imaging of the liver in patients with chronic liver damage.MR images were obtained after intravenous bolus injection of gadopentetate dimeglumine in 100 patients with chronic liver damage. Test bolus imaging was performed to determine the aortic transit time. A 26-second spoiled gradient-recalled-echo sequence was used. Patients were randomized into four groups so that the middle of k space was acquired at 5, 10, 15, and 20 seconds for the first phase and 45, 50, 55, and 60 seconds for the second phase, respectively, from the time of arrival of contrast material in the abdominal aorta. Mean signal intensities of the liver, spleen, and abdominal aorta were measured, and images were reviewed prospectively by three radiologists in consensus. Analysis of variance, the Scheffé criterion for continuous data, and the Kruskal-Wallis test for categorical data were used for statistical evaluation.Intense splenic enhancement with the moiré pattern without intense hepatic enhancement occurred at 10-15 seconds. Aortic and splenic enhancement significantly decreased from 45 to 50 seconds (P.05). Spleen-to-liver contrast-to-noise ratio began to decrease at 20 seconds and decreased constantly over time. Qualitative results correlated well with quantitative results.Biphasic imaging with k space centered at 10-15 and 50 seconds or later after arrival of contrast material in the abdominal aorta may be the optimal technique to obtain ideal contrast enhancement. Empirically, delays of 28-34 and 68 seconds or later after initiating contrast material injection may be effective for biphasic imaging.

Using a stretched-polymer-film technique, we could assign the resonance fields in the electron paramagnetic resonance (EPR) spectra of the lowest excited triplet (T1) states of p- and m-polyphenyl molecules [C6H5−(1,4-C6H4)n-2−C6H5, C6H5−(1,3-C6H4)n-2−C6H5, respectively] relative to the spin axes. In this case, the set of the zero-field splitting (ZFS) parameters is unique for a p-polyphenyl molecule but not for a m-polyphenyl molecule composed of more than three benzene rings. Taking the z axis as being perpendicular to the molecular plane and the x axis as being rather close to the longest direction of the molecule, we obtained interesting relations of the ZFS parameters to the conformation. The present calculations showed that for p-polyphenyl molecules the conjugated system is delocalized along the longest molecular axis and the |Z| values decrease by an increase of the composing benzene rings and that for the m-polyphenyl molecules the T1 character is localized at every composing biphenyl skeleton an...

The inotropic effect of diazepam, a benzodiazepine derivative, and its mechanism of action were examined using guinea pig heart and single ventricular cell preparations. In Langendorff hearts and right ventricular free-wall preparations, diazepam (10 to 100 microM) produced a monophasic negative inotropic effect in a concentration dependent manner. Neither a central type (flumazenil 1 microM) nor a peripheral type (PK11195 10 microM) of benzodiazepine receptor antagonist antagonized the monophasic negative inotropic effects of diazepam. Diazepam (10 to 100 microM) shortened action potential duration of papillary muscle in a concentration dependent manner. In isolated single ventricular cells, diazepam (30 and 100 microM) inhibited the calcium current (I(Ca)) in a concentration dependent manner. Diazepam produced a significant decrease in I(Ca) elicited by first depolarizing pulses, however, the decrease of I(Ca) was not augmented during a train of depolarizing pulses. Thus, diazepam appears to produce a tonic block of cardiac calcium channels and the mode of inhibition is clearly different from the use-dependent block of verapamil. From these results, it was concluded that diazepam produces a monophasic negative inotropic effect that is independent of the benzodiazepine receptor, and is probably mediated through an inhibition of I(Ca) in guinea pig heart preparations.

We reported previously that human fetal skin fibroblast migration into a denuded area was stimulated by an autocrine factor, basic fibroblast growth factor (bFGF). Since the signal transduction pathway of this migration is unknown, we attempted to clarify it by comparing this fibroblast migration with a previously reported bovine endothelial cell migration into a wounded area stimulated by an addition of bFGF, in which the bFGF signal was mediated by phospholipase A(2)-coupled G-protein and phospholipase A(2) (PLA(2)) via arachidonic acid. Our study demonstrated that pertussis toxin, a specific inhibitor of PLA(2)-coupled G-protein, did not suppress human fetal skin fibroblast migration, but 2-(p-amylcinnamyl)amino-4-chlorobensoic acid (ONO-RS-082), a PLA(2) inhibitor, did. Since ONO-RS-082 is a non-specific PLA(2) inhibitor, a cytoplasmic, Ca-dependent PLA(2) (cPLA(2)) inhibitor, AACOCF3, was examined. AACOCF3 suppressed cell migration in certain concentrations. The PLA(2) inhibitor-suppressed cell migration was restored by adding arachidonic acid, and cell migration suppressed by anti-bFGF antibodies was restored by adding arachidonic acid. In addition, pertussis toxin did not suppress arachidonic acid release, which shows an action of PLA(2), but AACOCF3 did. These results indicate that human fetal skin fibroblast migration stimulated by an autocrine factor, bFGF, was mediated by PLA(2) via arachidonic acid without the involvement of PLA(2)-coupled G-protein.

To investigate the effect of imaging delay on gadolinium enhancement of the pancreas and peripancreatic vessels at dynamic gradient-recalled-echo magnetic resonance (MR) imaging of the pancreas.Dynamic MR images were obtained after intravenous bolus injection of gadopentetate dimeglumine in 75 patients with no pancreatic malignancies. Test-bolus imaging was performed to determine aortic transit time in individual patients. Patients were randomly assigned so that the middle of k space was acquired at 5, 15, 25, 35, or 45 seconds after arrival of contrast material in the abdominal aorta. Mean signal intensities of pancreas, liver, and peripancreatic vessels were measured, and images were qualitatively assessed by two radiologists.The best pancreatic enhancement occurred at a delay of 15 seconds (P.05). The best enhancement of the liver and peripancreatic vessels occurred at 25 seconds or later (P.05). Qualitatively, the best images of the pancreas were obtained at 15 seconds, and the best images of the liver and peripancreatic vessels were obtained at 25 seconds or later.Biphasic imaging at 15 and 45 seconds or later after arrival of contrast material in the abdominal aorta is a practical method for acquisition of high-quality dynamic gradient-recalled-echo MR images of the pancreas.

The reversible thermal transition of soluble branched starch chains prepared from slightly acid-treated potato starch granules (ATS) was investigated. Potato starch was immersed in 15% sulfuric acid to obtain ATS with a 1% hydrolysis rate. About half of the molecules of ATS, which spontaneously formed large aggregates with a mass of a few million daltons in aqueous solution, was fractionated and soluble branched starch chains with a relative molecular weight (Mr) of 8.91 x 10(4) were obtained. Structural analysis indicated that the soluble branched starch chains consisted of three unit chains with Mr 7,900 and 21 unit chains with Mr 2,700. DSC and FT-IR measurements showed that the soluble branched starch chains underwent a reversible thermal transition, which is considered to be a helix-coil transition, during heating and cooling, but a debranched sample and beta-limit dextrins showed substantially different thermal behavior, indicating the contribution of the ordered structure of the branched chains.

Doxorubicin (30 microM) caused a biphasic (early and late phase) positive inotropic effect. A high concentration (200 microM) of this agent caused a stronger early phase, but a weaker late phase. The early phase caused by the high concentration of doxorubicin was significantly reduced by cyclopiazonnic acid or thapsigargin, although it was not altered by ryanodine, verapamil, or nifedipine. The late phase in the presence of the high concentration of doxorubicin was slightly enhanced by cyclopiazonic acid, verapamil or nifedipine, and markedly enhanced by ryanodine. At the end of the 4-hr experimental period in the presence of the high concentration of doxorubicin, the positive inotropic effects of CaCl2 were completely diminished. Verapamil almost completely restored the action of the doxorubicin.

The Ca(2+)-releasing mechanisms of the sarcoplasmic reticulum responsible for cardiac muscle contraction in carp were examined and compared with these mechanisms in rats. Morphologically, the ventricular muscles of the carp heart are composed of an outer compact and an inner spongy layer. In the present study, ventricular muscle preparations were obtained from the compact layer of the carp heart, because the spongy layer does not contribute significantly to the overall force of contraction. Electron microscopic observations showed that the sarcoplasmic reticulum in the carp ventricular muscle, compared to that in the rat ventricular muscle, was poorly developed. Consistent with this finding, specific [3H]ryanodine binding to partially purified sarcoplasmic reticulum preparations obtained from carp ventricular muscle as compared with the preparations isolated from the rat ventricular muscle showed a lower affinity and a smaller number of binding sites. Additionally, a higher Ca2+ concentration was required to cause a half maximal stimulation of [3H]ryanodine binding in the carp heart. In skinned ventricular muscle fibers isolated from carp hearts, the caffeine-induced contracture was significantly weaker than that observed in rat hearts. These results suggest that, in carp hearts, the sarcoplasmic reticulum has an important role as a supply source of Ca2+ for muscle contraction, though the storage capacity and/or amount of Ca2+ release in carp was significantly smaller than that in rats.

The alteration in hepatic glutathione peroxidase (GPx) produced by polychlorinated biphenyls (PCBs) was studied in vivo in aryl hydrocarbon (Ah)-responsive C57BL and -less-responsive DBA strains of mice. 3,3',4,4',5-Pentachlorobiphenyl (PCB 126), one of the high-affinity ligands for the Ah receptor, significantly reduced Se-dependent GPx activity in C57BL mice, but not in DBA mice. A reduction in activity in C57BL mice was also observed following treatment with a high dose of 3,3',4,4'-tetrachlorobiphenyl with lesser affinity for the Ah receptor than PCB 126, but not by 2,2',5,5'-tetrachlorobiphenyl, a low-affinity ligand. To assess the effects on GPx in the liver, the content of reduced glutathione (GSH), an obligate co-factor for GPx, and the activity of two enzymes, γ-glutamyl transpeptidase (γ-GTP) and glutathione reductase (GR), which play a role in supplying GSH were determined after PCB treatment. The results showed that although the hepatic activity of γ-GTP and GR was affected differently by PCB 126, the content of GSH was slightly increased rather than reduced in both strains of mice. The activity of non-Se-dependent GPx, which is due to the catalysis by some isozymes of glutathione S-transferase (GST), was significantly increased only in C57BL mice by PCB 126 treatment. Immunoblot analysis demonstrated that the induction of the class θ GST, which is a potent reducer of peroxides (Hiratsuka et al., 1995. Biochem. Biophys. Res. Commun. 212, 743) reflects the enhancement of the above activity. These results suggest that (i) the PCB-induced reduction in Se-dependent GPx activity is mediated by a mechanism involving the Ah receptor; and (ii) a concomitant increase in the class θ GST partially rescues the Ah-responsive mice from coplanar PCB-induced oxidative stress.

We examined the in vivo effect of a highly toxic coplanar polychlorinated biphenyl (PCB) on the hepatic activity of glucose 6-phosphate dehydrogenase (G6PDH) in aryl hydrocarbon (Ah)-responsive (C57/BL) and -less-responsive (DBA) strains of mice. The activity in the C57BL strain was moderately increased by 3,3',4,4',5-pentachlorobiphenyl (PCB 126) in a dose dependent manner. However, this was not observed in DBA mice although greater doses were injected. 2,2',5,5'-Tetrachlorobiphenyl (PCB 52) with a non-planar structure did not increase G6PDH activity. The increase in G6PDH activity with PCB 126 was also seen in rats, but not in guinea pigs. The activity in the latter species was decreased rather than increased. These results suggest that the induction of hepatic G6PDH by coplanar PCB is mediated by a mechanism involving the Ah receptor, and the response was highly species-specific.

Effects of central nervous stimulants on the spino-bulbo-spinal reflex potential were evaluated in anesthetized intact cats, and compared with those on segmental spinal reflex potentials in anesthetized spinal cats. In spinal cats, strychnine augmented polysynaptic reflex potential, picrotoxin inhibited dorsal root reflex potential, aminopyrine potentiated mono- and poly-synaptic reflex potentials but inhibited dorsal root reflex potential, and 4-aminopyridine potentiated all the three types of segmental reflex potentials. A combination of fenbufen, a non-steroidal antiinflammatory agent, and enoxacin, a new quinolone antimicrobial, inhibited all the three types of segmental reflex potentials. In contrast, all these drugs consistently produced an augmentation of the spino-bulbo-spinal reflex potential in anesthetized intact cats. From these findings, we suggest that the spino-bulbo-spinal reflex potential may be used as an electrophysiological parameter for the evaluation of central nervous stimulants.

Ca2+ sensitivity and caffeine-induced sensitivity changes in skinned carp heart fibers were compared with those of guinea pig and rat heart. The Ca2+ concentration-response curves of saponin-treated left atrial skinned fibers obtained from guinea pig and rat were almost identical. Doses of 5 and 20 mmol·l-1 caffeine shifted this curve to the left. However, when a relatively high concentration (50 mmol·l-1) of caffeine was used, the left-ward shift was reduced. Caffeine reduced the peak of the Ca2+ concentration-response curve. The Ca2+ concentration-response curve of carp atrial skinned fiber is almost identical to that of guinea pig and rat. However, a further increase in Ca2+ sensitivity was observed even when 50 mmol·l-1 caffeine was added. Similarly, a decrease in the response curve peak was also observed. Ca2+ sensitivity in ventricular skinned fibers obtained from carp was almost the same as that observed for the atrial, but the increase in Ca2+ sensitivity due to caffeine was larger In addition, a further increase was also observed when 50 mmol·l-1 caffeine was added. These results indicate that the Ca2+ sensitivity of contractile proteins in atrial muscles from carp heart is the same as that of guinea pig and rat. It is, however, assumed that there are some differences in properties in the contractile proteins. It is also assumed that there are some differences between the atrial and ventricular muscles of carp heart.

Dilution is a simple method to induce shifts of the association—dissociation equilibria of protein subunits. Excimer fluorescence is useful to monitor changes of equilibria in dilute solution, which has been shown in a well-characterized protein, actin. Actin was labeled with a fluorescent probe; N -(1-pyrenyl)iodoacetamide. When actin was diluted in low ionic strength buffer, the relative excimer fluorescence decreased. This arose from the conformational drift of actin, which resulted in a change in the association-dissociation equilibria of actin subunits in the dilute solution. Since dilution effects are often observed in other proteins, excimer fluorescence would be a useful sensitive technique to detect shifts of association-dissociation equilibria in dilute solution.

To compare total body weight (TBW), lean body weight (LBW) and body surface area (BSA) for the adjustment of the iodine dose required for contrast-enhanced multi-detector computed tomography (MDCT) of the aorta and the liver. One hundred and three patients undergoing MDCT of the abdomen were randomised into three groups: the TBW group receiving 0.6 g iodine/kg of TBW (n = 33), the LBW group receiving 0.75 g iodine/kg of LBW (n = 35) and the BSA group receiving 22 g iodine/m2 (n = 35). ∆HU (increases in CT value) per gram of iodine (∆HU/g) and adjusted maximum hepatic enhancement (adjusted MHE; ∆HU/[g iodine/kg]) correlated with three groups using linear regressions. Correlation coefficients of ∆HU/g were 0.67 (TBW), 0.86 (LBW) and 0.85 (BSA) for the aorta, and 0.74 (TBW), 0.77 (LBW) and 0.84 (BSA) for the liver. Adjusted MHE was constant at 70.2 with LBW and at 2.69 with BSA, but correlated positively with TBW (r = 0.58, P

The ammonia-oxidizing chemoautotrophic bacterium Nitrosomonas europaea possesses prominant succinate-reducing activity of succinyl-Coenzyme A synthetase (SCS, EC 6.2.1.5). SCS was purified as an electrophoretically homogeneous protein from Nitrosomonas europaea strain ATCC 25978 about 275-fold, with a 3.9% activity yield. The molecular mass of the native enzyme was estimated to be about 130 kDa by gel filtration, whereas SDS-PAGE gave two protein bands with M r values of 29 (α) and 36 kDa (β). The isoelectric point of the enzyme was 5.3. The apparent K m values of the enzyme for ATP, succinate and CoA were 0.4 mM, 5 mM and 0.1 mM, respectively. The pH and temperature optima of the SCS were about 5.0 and 55°C, respectively. The SCS was stable in the pH range of 8.0–10.0 and up to 70°C. The enzyme was thermostable; 50% of the enzyme activity was retained at 90–100°C for 10 min. The SCS was activated by Mg 2+ at 1.0–100 mM, but inhibited by Cu 2+ (0.1 mM) and SDS (1.0 mM). The enzyme utilized ATP as the preferred substrate.

Ni(tmtaa) efficiently catalyzes the reductive dehalogenation of alkyl halide, yielding alkane with either NaBH4 or NaBH(OMe)3 under mild condition. This system is considered to be a model of factor F430, the active center of the methyl coenzyme M reductase. Deuterium incorporation into the alkane suggests that the reaction involves not only an electron transfer, but also the nucleophilic substitution of a halide. The ESR spectrum of Ni(tmtaa)/NaBH4 shows the formation of the NiI species, which is probably a catalytic-active species.