Analysis of the linear oscillation dynamics of Fluidyne engines.

A Fluidyne engine is a liquid piston Stirling engine that uses thermally induced self-sustained oscillations of water and air that are filled in a looped tube and tuning column. It presents high potential for use as a low-temperature-difference Stirling engine with a simple structure. This study analyzes the linear oscillation dynamics of the Fluidyne from a thermoacoustic point of view, with particular emphasis on the local specific acoustic impedance of the working gas, which is given by the ratio of the complex amplitudes of the pressure and velocity oscillations in the regenerator of the Fluidyne. The frequency dependence of the specific acoustic impedance indicates that the gas in the regenerator region undergoes a thermodynamic cycle equivalent to the Stirling cycle when the oscillation frequency is equal to the natural oscillation frequency of the U-shaped liquid column in the Fluidyne. The analysis of the natural oscillation modes determined two key parameters for the desired specific acoustic impedance: the tuning column length and the connecting position to the loop. Experimental verification was achieved via measurements of the onset temperature ratio and acoustic field of a prototype Fluidyne engine.

Long-term clinical impact of serum albumin in coronary artery disease patients with preserved renal function.

BACKGROUND AND AIMS: Low serum albumin level is reportedly associated with worse clinical outcomes in patients with chronic kidney disease (CKD). However, associations between decreased serum albumin level and outcomes in non-CKD patients with coronary artery disease (CAD) remain unclear. Therefore, we aimed to evaluate the prognostic value of serum albumin concentrations in stable CAD patients with preserved renal function. METHODS AND RESULTS: We studied 1316 patients with CAD and preserved renal function (estimated glomerular filtration rate ≥60 mL/min/1.73 m2) who underwent their first PCI between 2000 and 2011 and had data available for pre-procedural serum albumin. Patients were assigned to quartiles based on pre-procedural albumin concentrations. The incidence of major adverse cardiac events (MACE), including all-cause death and non-fatal myocardial infarction, was evaluated. Mean albumin concentration was 4.1 ± 0.4 g/dL. During the median follow-up of 7.5 years, 181 events occurred (13.8%). Kaplan-Meier curves revealed that patients with decreased serum albumin concentrations showed a higher event rate for MACE (log-rank, p < 0.0001). Using the highest tertiles (>4.3 g/dL) as reference, adjusted hazard ratios were 1.97 (95% CI, 1.12-3.55), 1.77 (95% CI, 0.99-3.25), and 1.19 (95% CI, 0.68-2.15) for serum albumin concentrations of <3.9, 3.9-4.0, and 4.1-4.3 g/dL, respectively. Decreased serum albumin concentration was associated with MACE even after adjusting for other independent variables (HR, 2.21 per 1-g/dL decrease; 95% CI, 1.37-3.56, p = 0.001). CONCLUSION: Decreased serum albumin concentration independently predicted worse long-term prognosis in non-CKD patients after PCI. Pre-procedural serum albumin concentration could offer a useful predictor for patients with CAD and preserved renal function.

Genetic polymorphisms in folate pathway enzymes as a possible marker for predicting the outcome of methotrexate therapy in Japanese patients with rheumatoid arthritis.

BACKGROUND: Low-dose methotrexate (MTX) therapy is widely used in the treatment of rheumatoid arthritis (RA). Though the difference in response to MTX between patients with RA is large, the factors that contribute to this variability remain unclear. OBJECTIVE: We aimed to identify those factors with a particular emphasis on the pharmacogenetics of MTX. METHOD: We evaluated the association of possible factors, including genetic polymorphisms of folate metabolic pathway enzymes, with the cumulative value of C-reactive protein, an index of MTX anti-inflammatory efficacy, in 87 Japanese patients with RA. RESULTS: Polymorphisms of the reduced folate carrier gene (RFC) G80A and of the gamma-glutamylhydrolase gene (GGH) C-401T were more closely associated (beta = 2.1194, P = 0.0017) than other polymorphisms, with the anti-inflammatory response to MTX. CONCLUSION: Patients with RA having RFC 80A and GGH-401T alleles were less responsive to MTX than those with RFC 80A and without GGH-401T alleles. Thus, this data may be useful for guiding treatment of RA patients with MTX.

Relationship between number of natural teeth in older Japanese people and health related functioning.

The objective was to assess the relationship between number of functional occluding natural pairs of teeth and health related functioning in older free living Japanese people using the SF-20. The participants were 107 elderly people aged 80 years. Health related functioning was measured with the SF-20. The numbers of functional occluding natural pairs of teeth (OPs) were calculated and scored as follows: 1, for each pair of anterior teeth and premolars in occlusion. Molar functional natural occluding pairs were scored 2 for each occluding pair. The number of functional occluding pairs was assessed separately as anterior natural occluding pairs (AOPs) and posterior occluding pairs (POPs). There were significant differences in the role functioning subscale of SF-20 between those who were edentulous and those with one to nine natural teeth and 10 or more natural teeth (P = 0.030). Those with one to six AOPs had significantly higher role functioning than the zero AOPs group (P = 0.042). Those with 1-12 POPs also had significantly higher role functioning scores than the zero natural POPs group (P = 0.007). However, there were no significant relationships between number of natural teeth, OPs or AOPs, and POPs on the one hand, and all other subscales of SF-20 on the other hand. The community-dwelling 80-year-old Japanese people in this study had overall good health related functioning. The number of functional occluding pairs of natural teeth, especially POPs, was related with the role functioning subscale of SF-20 but had no significant relationships to the other dimensions of SF-20.

Effects of smoking and drinking habits on the incidence of periodontal disease and tooth loss among Japanese males: a 4-yr longitudinal study.

OBJECTIVE: We investigated the risk of periodontal disease and tooth loss, associated with habits of smoking and alcohol consumption, in a longitudinal study. SUBJECTS AND METHODS: The subjects were 1332 Japanese males, 30-59 yr of age, who were free from periodontal disease at the baseline check-up, and who underwent a second check-up 4 yr later. Periodontal disease was diagnosed using the community periodontal index score, based on the clinical probing of pocket depth (> or = 4 mm). Smoking and alcohol consumption patterns were evaluated using a self-administered questionnaire. RESULTS: A dose-response relationship was observed between the amount of smoking and the incidence of periodontal disease in each age group. The overall odds ratios (95% confidence intervals), adjusted for age and alcohol, were 1.51 (0.95-2.22), 1.58 (1.13-2.22) and 2.81 (1.96-4.03), among smokers consuming 1-19, 20 or 21 or more cigarettes per day, respectively, with a significant linear trend (p < 0.0001). A similar association was found between smoking and tooth loss, except for the 50-59-yr-old age group. The adjusted odds ratios were 1.26 (0.60-2.64), 2.01 (1.21-2.32) and 2.06 (1.23-3.48), respectively. A significant linear trend between smoking and tooth loss was also observed (p = 0.01). Ex-smokers showed no significant difference compared with nonsmokers. We also found a significant linear trend between alcohol consumption and tooth loss among 30-39-yr-old subjects, while no relationship was observed between alcohol consumption and periodontal disease. CONCLUSION: Cigarette smoking was found to be an independent risk factor for periodontal disease and tooth loss. Alcohol consumption was a limited risk factor for tooth loss in the younger age group, but was unrelated to periodontal disease. To prevent periodontal disease and tooth loss, health practitioners need to encourage people to stop smoking or not to start.

Growth stimulation and inhibition effects of 4-hydroxybenzoic acid and some related compounds on the freshwater green alga Pseudokirchneriella subcapitata.

4-hydroxybenzoic acid (4-HBA) exhibited low algal toxicity with the 72-h median inhibition concentration (IC50) of 9.9 mmol/L in the standard growth inhibition test using the freshwater green alga Pseudokirchneriella subcapitata. In contrast, it stimulated the algal growth at lower concentrations ranging from 0.1 to 1.0 mmol/L. Comparative studies with benzoic acid and 2- and 3-hydroxybenzoic acids (2-HBA and 3-HBA) indicated that 2-HBA was the most toxic, giving a 72-h IC50 of 0.172 mmol/L, and 4-HBA was the least toxic and that only 4-HBA had the pronounced growth stimulation activity. In a semicontinuous exposure to 4-HBA (0.15 and 0.3 mmol/L), algae maintained increased cell growth compared with controls during up to 10 times consecutive batch cultures, without any indication of adaptive responses to the growth enhancing effect of 4-HBA. Return to the clean standard medium of the exposed cells resulted in the quick recovery from the stimulant effect. Furthermore, 4-HBA (0.3 mmol/L) was found to diminish the toxicity of 2-HBA (<1.0 mmol/L). The presence of such compounds in the complex mixture might interact with other toxicants to alter the whole toxicity when assessed by the algal growth inhibition test. The effects of 4-HBA on P. subcapitata growth observed in the present study are not expected for planktonic algae in the aquatic environments, because known environmental concentrations are far below the effective concentration range.

Intra-oral fluoride retention 3 minutes after fluoride mouthrinsing in 4- to 5-year-old children: effects of fluoride concentration and rinsing time.

This study was undertaken to explore the site-specific retention rate and the possibility of shortening fluoride (F) mouthrinsing time of kindergarten children. Fluoride retention after 10-, 20- and 30-second mouthrinsing was determined in 43 kindergarten children aged 4-5 years. Tooth surfaces were sampled by a paper point method. Fluoride concentrations in the salivary film on tooth surfaces increased from primary molars to primary incisors in the maxilla and decreased from primary molars to primary incisors in the mandible. The fluoride solution reached the primary molars even after a 10-second rinse, but F concentrations were higher after 20 s than after 10 s and significantly higher after 30 s than after 10 s. No significant difference was observed between 20 and 30 s. The average total F retained in the mouth was 0.13 mg after 20 s and 0.17 mg after 30 s. It was concluded that 30-second mouthrinsing, which is used extensively in Japanese kindergartens, can be shortened to 20 s.

Effects of carbon dioxide pneumoperitoneum on hemodynamics in cirrhotic rats.

BACKGROUND: The aim of our study was to investigate the effect of carbon dioxide pneumoperitoneum on systemic and splanchnic hemodynamics in cirrhotic rats. METHODS: Sprague-Dawley rats (n = 80) were used in this study. Liver cirrhosis was induced by thioacetamide administration intraperitoneally (200 mg/kg body weight, twice a week for 16 weeks). The radioactive microsphere method was used to measure systemic and regional hemodynamic parameters before, 1 h after the start, and 1 h after the release of pneumoperitoneum. RESULTS: Splanchnic blood flow and cardiac index were significantly depressed during pneumoperitoneum in liver cirrhosis and control groups, but no significant differences were seen between the two groups. In both groups, portal venous inflow decreased and hepatic arterial blood flow increased significantly during pneumoperitoneum. However, during pneumoperitoneum, total hepatic blood flow as a percentage of its value before pneumoperitoneum was lower in cirrhotic rats (71.0%) than in control rats (91.9%) (p <0.05, Mann-Whitney U-test). CONCLUSIONS: Carbon dioxide pneumoperitoneum markedly decreases total hepatic blood flow in cirrhotic rats due to the impaired hepatic arterial buffer response. Liver function should be carefully controlled in cirrhotic patients after laparoscopic surgery with pneumoperitoneum.

Mechanism of protection by S-(1,2-dicarboxyethyl)glutathione triester against acetaminophen-induced hepatotoxicity in rat hepatocytes.

Treatment with the triester of S-(1,2-dicarboxyethyl)glutathione (DCE-GS) prevented the hepatotoxicity induced by acetaminophen via elevation of the glutathione (GSH) level in rat hepatocytes. This elevation of the GSH level in rat hepatocytes by DCE-GS triester was dose- and time-dependent (2.1-fold in 24 h with 0.5 mm). DCE-GS triester increased the GSH level much more effectively than GSH, DCE-GS, and DCE-GS monoester and diester. Furthermore, the activity of y-glutamylcysteine synthetase (gamma-GCS), the rate-limiting enzyme in GSH biosynthesis, was also increased by DCE-GS triester treatment (1.4-fold in 24 h with 1.0 mm). In contrast, with a rat liver homogenate, DCE-GS increased the y-GCS activity, whereas DCE-GS triester had no effect on this activity. These results suggested that DCE-GS triester, which is transported into hepatocytes much more effectively than DCE-GS and other DCE-GS esters due to its greater lipophilicity, was hydrolyzed to DCE-GS, and then the DCE-GS produced increased the GSH level via activation of gamma-GCS in rat hepatocytes.

Chemistry of trichlorofluoromethane: synthesis of chlorofluoromethyl phenyl sulfone and fluoromethyl phenyl sulfone and some of their reactions.

It was observed that the reaction of CFCl3 with thiophenoxide gave only 10% of the corresponding thioether. On the other hand, these thioethers could be prepared in excellent yield from diaryl disulfides and CFCl3 in the presence of sodium hydroxymethanesulfinate in aqueous DMF at 4 atm pressure of nitrogen. Dechlorination of the thioether (PhSCFCl2) with different reducing agents were studied. Most of the reducing agents eliminated both fluorine and chlorine functionalities or gave the hydrolyzed products. But its sulfone on treatment with Zinc in methanol gave monochlorofluoromethyl and fluoromethyl phenyl sulfone in good yields. Darzens reaction of these compounds was also studied.

A possible role of glutathione and glutathione disulfide in tracheary element differentiation in the cultured mesophyll cells of Zinnia elegans.

We investigated the relationship between the cellular redox state of GSH or GSSG and tracheary element (TE) differentiation using a Zinnia experimental system, in which isolated mesophyll cells transdifferentiate to TEs. TE differentiation was suppressed by the application of L-buthionine sulfoximine (BSO), a potent inhibitor of GSH biosynthesis, at the early stage of cell culture. Application of GSSG at the early culture stage promoted the differentiation, but that of GSH or GSSG at an advanced period of culture suppressed the differentiation. Application of GSH and GSSG nullified the TE differentiation-suppressing effect of BSO. The results suggest that changes in the redox states of GSH and GSSG have a role in TE differentiation.

fac-Trichloro(quinolin-8-ylimido-N,N')(triphenylphosphine-P)rhenium(V).

The Re atom in [Re(C(9)H(6)N(2))Cl(3)(C(18)H(15)P)] is octahedrally coordinated by three Cl atoms in facial positions, two N atoms from 8-imidoquinoline (imq) and one P atom from triphenylphosphine. The Re-N(imido) distance [1.760 (9) and 1.772 (8) A] for imq is very short and implies double-bond character. The trans influence of the P atom is indicated. Intra- and intermolecular pi-pi interactions between the pi-rings in the complex are also observed.

Use of fluoridated dentifrice and glucose retention at the approximal areas of anterior teeth.

The present study was undertaken to learn to what extent the use of dentifrice with fluoride affected glucose retention after glucose rinsing. Fifty-eight subjects consisting of forty male adults and eighteen female adults whose average age was 21.9 years were divided at random into two groups; one group used fluoridated dentifrice and the other group used nonfluoridated dentifrice. Subjects rinsed their mouths for fifteen seconds with 20 mL of 0.5 M glucose solution. Samples of saliva were taken from the approximal areas between the right and left central incisors of the maxilla and mandible by inserting the tip portion of a paper point three-minutes after the glucose rinsing, sample of saliva were taken from the neighboring approximal areas of the left central and left lateral incisors. Glucose content of the paper points was determined using the enzyme membrane method. Determinations were made before and at the end of the first, third, and fifth month over a five-month period. Fluoride concentrations in the resting saliva were also determined in different months during this period. At three-minutes and six-minutes, glucose retention in the group using fluoridated dentifrice was found to decrease slightly throughout the experiment; while glucose retention in the group on nonfluoridated dentifrice leveled off or increased in the fifth month. Fluoride concentration in the resting saliva increased during the experiment in the group using fluoridated dentifrice; while fluoride concentration in the group using nonfluoridated dentifrice did not change. It was concluded that the regular use of fluoridated dentifrice made glucose retention slightly lower and fluoride level in whole saliva higher.

[Evaluation of cerebrovascular events in patients with rheumatoid arthritis].

OBJECTIVE: We evaluated cerebrovascular events (cerebral infarction or cerebral bleeding) in patients with rheumatoid arthritis (RA). METHODS: Prognosis and the causes of death among 1100 RA patients from 1995 to 1999, were analyzed. 34 RA patients were complicated by cerebrovascular events. About them, hemoglobin, platelet, C-reactive protein, rheumatoid factor, total cholesterol, triglyceride, duration of disease, functional class, and dose of steroids per day were measured. RESULT: Among 1100 patients with RA, 90 died at the age of 70.2. Of these patients, 24 (26.7%) died of cerebrovascular events, 19 (21.1%) of heart failure, 16 (17.8%) of infectious diseases, 10 (11.1%) of malignant tumors, and 9 (10%) of renal failure. When RA patients who died of cerebrovascular events were compared with those who died of other causes, the dose of steroid was significantly lower and the age was higher in RA patients who died of cerebrovascular events. However, there were no significant differences in total cholesterol and triglyceride levels between the two groups. Although the major cause of death in RA patients was reported to be complication by cardiovascular diseases, infectious diseases, or renal failure, the frequency of deaths was higher in elderly RA patients complicated by cerebrovascular events. When the frequency of complication by cerebrovascular events was investigated in all RA patients including those who survived, 24 died and 10 survived. The frequency of complication by cerebral infarction was higher than that of complication by cerebral bleeding in RA patients who died of cerebral events. CONCLUSION: RA patients can live longer with improvements in care and treatment, the number of elderly RA patients who may died of complication by cerebrovascular events may gradually increase.

[A multicenter cross-sectional study on the Health Related Quality of Life of patients with rheumatoid arthritis using a revised Japanese version of the Arthritis Impact Measurement Scales Version 2 (AIMS 2), focusing on physical disability and its associative factors].

OBJECTIVE: A multicenter cross-sectional survey was conducted to study the current status of Health Related Quality of Life (HRQL) of Japanese patients with rheumatoid arthritis using a revised Japanese version of the AIMS 2, to investigate the association among the self-report physical disability scores and demographic, socioeconomic, and clinical variables in these patients. METHODS: A Japanese version of the AIMS 2 was administered to the randomly chosen 1614 patients with classical and definite rheumatoid arthritis attending arthritis clinics at eleven hospitals across the country. Self-report functional disability scores (FDSs) were calculated, by which patients were classified into five groups with graded levels of disability. Univariate correlations were examined between FDSs and the scores of the other four components of AIMS-HRQL, disease duration, age, medical costs, and physical and laboratory measures. Analysis of variance was performed to test for among level differences of these variables in each group of patients. Mean values and standard deviations of FDSs were calculated and analysis of variance was used to test for among level differences of the following factors: demographic, socio-economic, clinical measures, and treatment status. RESULTS: Among four scales composing the AIMS 2-HRQL, work disability scores were most strongly correlated with FDSs, followed by the scores of pain, affection and social interaction. The more severely disabled group proved to have weaker grip strength, higher joint count, longer disease duration, higher ESR and blood level of CRP, and lower level of Hb. Patients with more disabilities proved to be older, pay more medical costs, have longer duration of morning stiffness, and higher level of RF. Patients with more advanced Steinbrocker's functional class, doctor's global assessment, Steinbrocker's anatomical stage, higher daily dose of prednisolone intake, lower level of annual income and formal education, and patients taking more kinds of NSAIDs proved to be more severely disabled. Separate, single (never married, widowed), and divorced patients proved to be more severely disabled compared with married ones. Overall, females were more disabled than males. CONCLUSION: Physical disability is associated with the other important aspects of QOL, clinical signs and symptoms, and socio-economic conditions in RA patients. Prevention and management of physical disability should be seriously planned in consideration of the changes in these conditions in RA patients.