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We evaluated the predictivity and applicability of previously proposed models for the reproductive toxicity of chemicals to Daphnia magna [SAR QSAR Environ. Res. 27:10, 833–850] by using external data from the United States Environmental Protection Agency database ECOTOX. These models were based on quantitative structure–activity–activity relationships (QSAARs) and a quantitative activity–activity relationship (QAAR): the models can be categorized as acute-to-chronic models with (QSAAR) and without (QAAR) structural and physicochemical (e.g. distribution coefficients, logD) descriptors. We found that the QSAAR models were suitable for chemicals with an ‘–NH2attached to aromatic carbon’ sub-structure, whereas the QAAR model was better for multicomponent compounds, coordination complexes, tin compounds and straight-chain primary amines. For chemicals with a known specific mode of action (e.g. pesticides and antibacterial agents and their derivatives), toxicity estimation within the acute-to-chronic framework requires special attention. We evaluated the applicability of the models on the basis of the descriptors in the models. We recommend that chemicals be pre-screened before their toxicities are estimated with these models: pre-screening enabled the estimation of the toxicities of some chemicals within the applicability domains of the models. [ABSTRACT FROM PUBLISHER]

We constructed models for acute to chronic estimation of theDaphnia magnareproductive toxicities of chemical substances from theirDaphnia magnaacute immobilization toxicities. The models combined the acute toxicities with structural and physicochemical descriptors. We used multiregression analysis and selected the descriptors for the models by means of a genetic algorithm. Of the best 100 models (as indicated by the lack of fit score), 90% included the following descriptors: acute toxicity (i.e. an activity parameter), distribution coefficient (logD) and structural indicator variables that indicate the presence of –NH2attached to aromatic carbon and the presence of a chlorine atom. We compared the predictive abilities of five of these quantitative structure–activity–activity relationship (QSAAR) acute to chronic estimation models with the predictive ability of a simple linear regression model. The comparison revealed that inclusion of structural and physicochemical descriptors such as those in QSAAR models can improve models for extrapolation from acute to chronic toxicity. Our results also provide a QSAAR framework that is expected to be useful for the further development of chronic toxicity estimation models. [ABSTRACT FROM AUTHOR]

The influence of considering different downstream temperatures on the performance of a two-layer porous burner is studied numerically. A 3D numerical model based on a unit cell was implemented to correctly predict the momentum, heat and mass transfer at the interface of the two layers. Two operating modes are simulated corresponding to the burner radiating to cold and hot environments. When the burner radiates to a hot environment, its radiative heat losses are lower and, as a consequence, the temperatures and pollutants emissions are higher. Additionally, the flame front moves upstream and stabilizes nearer the interface of the two layers. [ABSTRACT FROM AUTHOR]

Masked hypertension is reported to have the same level of hazard risk of cardiovascular mortality and stroke morbidity as sustained hypertension. The number of managerial employees suffering from cardiovascular disease and stroke is known to be greater than other employee. The aim of this study was to compare the 24-h blood pressure (BP) recordings between elderly male managerial employees and retirees and to propose a strategy for identifying masked hypertension. A total of 38 males (16 managerial employees aged 50-69 years and 22 retirees aged 60-65 years) who were not taking any antihypertensive medications participated in this study. Their 24-h BP was measured by an ambulatory BP monitoring device. Daytime (9:00-17:00 h) BPs of the employees (mean, 139/92 mm Hg) were significantly higher than in the retirees (mean 124/80 mm Hg), while there was no difference in BP before and during sleep. In all, 5 of 16 employees (31%) who were diagnosed as normotensive (<140/90 mm Hg) at a periodic health check had hypertension (>135/85 mm Hg) in the morning measured by ambulatory BP monitoring, while 6 (38%) had a similar level of hypertension during the daytime (9:00-17:00h). These individuals were diagnosed as having masked hypertension. Multiple regression analyses showed that the job was the only factor that contributed to the difference in BP in the subjects during the daytime. This finding suggested that job stress seemed to be one of the main causes of masked hypertension. We argue that more frequent measurements of BP at the work place are necessary to identify subjects with masked hypertension. [ABSTRACT FROM AUTHOR]

Recent reports suggest that high blood pressure (BP) during the night is associated with hypertensive organ damage, and that increased BP in the morning is closely related to the incidence of stroke and ischemic heart disease. The aim of this study was to investigate the relationships between overnight urinary indicators and 24-hour (24-h) BP, especially in the morning and during sleep in the elderly. A total of 85 volunteers (males 43, females 42), aged between 51 and 76 years and not taking any antihypertensive medications, participated in this study. Their 24-h BP was measured by ambulatory BP monitoring every 30-minute using a TERUMO ES-H531 system. Overnight urine samples were collected using a proportional urine-sampling device, Urine mate P. Overnight sodium (UNan) and potassium (UKn) excretions were measured by an ion electrode method. Simple linear regression analyses showed that systolic blood pressure (SBP) in the morning and diastolic blood pressure (DBP) during sleep were negatively related with overnight urinary weight standardized for body weight (UWn/BW). Multiple regression analyses showed that SBP during the morning and during sleep was positively related to UNan and negatively related to UWn/BW. We also found a negative relationship between SBP during sleep and UKn. The study suggested that urine weight adjusted for BW was negatively related with 24-h BP, especially morning BP. Sodium excretion combined with a large volume of urine proportional to body weight may prevent increases in BP, especially in the morning. [ABSTRACT FROM AUTHOR]

Despite proven efficacy of maintenance pharmacotherapy in schizophrenia, indefinite neuroleptic treatment may not be optimal for all patients. It is uncertain how long maintenance therapy should be continued and how to identify those patients who can withdraw eventually from neuroleptics. Prospective randomized con-trolled studies are the ideal approach for evaluation of medication, however they are inevitably for the short term and may not be suitable for addressing the above-mentioned issue. In this study, we naturalistically followed up 30 remitted schizophrenics for 10.7 years on average and examined factors that might affect the outcomes. Of 30 remitted patients, 8 cases (26.7%) ceased neuroleptic use completely for more than 2 years. The details of clinical courses of those 8 cases were described as case reports in this report. Importantly, 4 of 8 withdrawal cases required 2 or more trials' in order for neuroleptic withdrawal to reach a drug-free state. Factors which significantly affected successful withdrawal involved the mode of onset and the ages at first neuroleptic withdrawal trial. Our results suggest that approximately one-fourth of completely remitted patients could withdraw neuroleptics, but certain cases may need withdrawal trials at least a few times to accomplish the drug-free state. [ABSTRACT FROM AUTHOR]

Guided waves propagating in a pipe consist of many modes with different velocities and dispersions. To analyze these complex guided waves through a normal mode expansion technique, that is the fundamental theory on guided waves, we must first extract guided wave modes from received signals. In this study, we develop a mode extraction technique in which many received signals at different circumferential positions can be processed based on the fact that guided wave modes have different displacement distributions in the circumferential direction. After discussing the relevant theory, we verify our mode extraction technique experimentally using eight signals at eight different circumferential positions. Moreover, we show that the circumferential position of an excitation transducer, as well as the distance between an excitation transducer and a receiver in a pitch-catch configuration can be identified using the mode extraction technique. [ABSTRACT FROM AUTHOR]

Purpose: The well-documented increases in malignant tumours in the A-bomb survivors have recently been supplemented by reports that non-cancer diseases, including cardiovascular disease, may also have increased in incidence with increasing radiation dose. Given that low-level inflammatory responses are widely accepted as a significant risk factor for such diseases, we undertook a detailed investigation of the long-term effects of ionizing radiation on the levels of the inflammatory markers C-reactive protein (CRP) and interleukin 6 (IL-6) in A-bomb survivors. Materials and methods: Blood samples were taken from 453 participants in a long-term epidemiological cohort of A-bomb survivors. Plasma levels of CRP and IL-6 were measured using standard antibody-mediated procedures. Relationships between CRP or IL-6 levels and radiation dose were then investigated by multivariate regression analysis. Blood lymphocytes from each individual were used for immunophenotyping by flow cytometry with murine monoclonal antibodies to CD3, CD4 and CD8. Results: CRP levels were significantly increased by about 31% Gy[sup -1] of estimated A-bomb radiation (p = 0.0001). Higher CRP levels also correlated with age, male gender, body mass index and a history of myocardial infarction. After adjustments for these factors, CRP levels still appeared to have increased significantly with increasing radiation dose (about 28% increase at 1 Gy, p = 0.0002). IL-6 levels also appeared to have increased with radiation dose by 9.3% at 1 Gy (p = 0.0003) and after multiple adjustments by 9.8% at 1 Gy (p = 0.0007). The elevated CRP and IL-6 levels were associated with decreases in the percentages of CD4[sup +] helper T-cells in peripheral blood lymphocyte populations. Conclusions: Our results appear to indicate that exposure to A-bomb radiation has caused significant increases in inflammatory activity that are still demonstrable in the blood of A-bomb survivors and which may lead to increased risks of... [ABSTRACT FROM AUTHOR]

OBJECTIVE: The autoimmune response appears to play an important role in some types of acute sensorineural hearing loss. Endolymphatic hydrops associated with fluctuating hearing loss has also been suggested to be caused by an immunological mechanism. Acute low-tone hearing loss (ALHL) associated with Meniere's disease (MD) is characterized by fluctuating hearing loss, and its etiology is thought to involve endolymphatic hydrops. The aim of this study was to attempt to determine the etiology of ALHL in MD. MATERIAL AND METHODS: A flow cytometer was used to analyze intracellular cytokine levels in peripheral blood from 19 patients with ALHL and 26 patients with MD and the data compared to those obtained from age- and gender-matched healthy volunteers. RESULTS: The patients with ALHL showed significantly increased levels of Th1 subsets (interferon-gamma-producing helper T cells) as compared to those in normal controls. The levels of Th2 (IL-4-producing helper T cells) subsets did not differ from those in the control group and thus Th1 predominated in ALHL patients. The patients with MD showed significantly increased natural killer cell activity but no Th1 dominance. These patients had no obvious systemic or local disease except in the inner ear. CONCLUSION: An abnormality of the Th1/Th2 balance in ALHL and increased natural killer cell activity in MD are thought to relate to inner ear disorder. These results are consistent with the possibility that the etiology of ALHL and MD involves an immune response. [ABSTRACT FROM AUTHOR]

Carbon nanotubes have a whisker-like structure so an extremely high strength and lack of plasticity are generally predicted. In-situ observations made by transmission electron microscopy, however, prove that carbon nanotubes bend plastically at room temperature. The bending process at the atomic level is suggested by a molecular mechanics calculation: a nanotube deforms elastically until certain critical curvature is attained; then the atomic bonding in the stressed side changes from a graphite-like bonding state to a diamond-like state. [ABSTRACT FROM AUTHOR]

We propose a three-step strategy that uses structural and physicochemical properties of chemicals to predict their 72 h algal growth inhibition toxicities againstPseudokirchneriella subcapitata. In Step 1, using a logD-based criterion and structural alerts, we produced an interspecies QSAR between algal and acute daphnid toxicities for initial screening of chemicals. In Step 2, we categorized chemicals according to the Verhaar scheme for aquatic toxicity, and we developed QSARs for toxicities of Class 1 (non-polar narcotic) and Class 2 (polar narcotic) chemicals by means of simple regression with a hydrophobicity descriptor and multiple regression with a hydrophobicity descriptor and a quantum chemical descriptor. Using the algal toxicities of the Class 1 chemicals, we proposed a baseline QSAR for calculating their excess toxicities. In Step 3, we used structural profiles to predict toxicity either quantitatively or qualitatively and to assign chemicals to the following categories:Pesticide,Reactive,Toxic,Toxic lowandUncategorized. Although this three-step strategy cannot be used to estimate the algal toxicities of all chemicals, it is useful for chemicals within its domain. The strategy is also applicable as a component of Integrated Approaches to Testing and Assessment. [ABSTRACT FROM AUTHOR]

The size distribution of gold nanoparticles was estimated based on the scattering intensity data obtained from small angle X-ray scattering (SAXS) and compared with the result of micrographs by transmission electron microscopy. The slope of the Guinier plot was used to estimate the mean size assuming a narrow particle size distribution. When the size distribution is narrow, the mean size can be easily obtained from slope of a Guinier plot of scattering data within 10% error. Additionally, assuming a lognormal size distribution, the size distribution and the mean size can be calculated using the experimental SAXS data in the fitting analysis. The histogram method, which utilizes the coefficient matrix of scattering intensity, was also applied to the estimation of the size distribution, and this method could be useful for a rough estimate of the size distribution. [ABSTRACT FROM AUTHOR]

Lithium-doped K0.5Na0.5NbO3 (KLNN) films were fabricated by chemical solution deposition on Pt/TiO2/SiO2/Si substrates. Homogeneous and stable precursor solutions were prepared by controlling the reaction of starting metal alkoxides. Perovskite KLNN single-phase thin films were successfully synthesized on Pt/TiOx/SiO2/Si substrates. The 0.75-μ m-thick KLNN film annealed at 650°C exhibited ferroelectric polarization hysteresis loops at -250°C. The loop at room temperature was round, indicating the film contained leakage components. The dielectric constant under zero bias was 490 at room temperature. A typical upside-down butterfly DC bias-capacitance curve was obtained in the KLNN film capacitors at room temperature, indicating that polarization reversal occurred in the obtained KLNN films. [ABSTRACT FROM AUTHOR]

Augmented expression of members of the heat shock protein 70 (Hsp70) family are frequently observed in various human cancers. In this study, we examined applicability of laser scanning cytometer (LSC) to evaluate the level of Hsp72, which is the member constitutively expressed and significantly induced after heat shock, in human tumour cell lines. The relative nuclear content of Hsp72 measured by LSC correlated well with the relative intracellular content determined by Western blotting (R = 0.906). Furthermore, there was a close relationship between the relative nuclear content of Hsp72 measured by LSC and the colony-forming ability in soft agar, one of the malignant characteristics of tumour cells (R = 0.880). These results indicate that LSC measurement is useful for predicting the degree of malignancy of cancer cells, as it is reliable, faster than Western blotting and more objective and quantitative than visual measurements. [ABSTRACT FROM AUTHOR]

Gamma/delta T-cell lymphoma (GDTL) is an uncommon lymphoma that was initially reported to involve only the liver and spleen. GDTL other than the hepatosplenic type is extremely rare. Frequent primary sites include skin and subcutaneous tissue, intestine, or nasal region. We report a case of GDTL of the omentum in a 54 year-old-man. The tumor cells are CD2  -  , CD3  +  , CD4  -  , CD5  -  , CD8  +  , CD56  +  , TIA-1  +  , granzyme B  ±  . They expressed the identical phenotype of intestinal GDTL. The patient was treated with 2 courses of CHOP which comprised cyclophosphamide, doxorubicin, vincristine and prednisolone, and 3 courses of EPOCH which comprised etoposide, prednisolone, vincristine, cyclophosphamide and doxorubicin. However, he failed to obtain remission. During the fourth course of EPOCH, muscle weakness of the lower extremities developed and intracranial masses were observed by computed tomographic scan of the brain. Dissemination of lymphoma to the central nervous system was considered and it may be attributable to the expression of CD56 in this case. High dose methotrexate (HD-MTX) chemotherapy successfully eliminated the omental tumor and reduced the size of the intracranial masses, thus HD-MTX appears to be an effective treatment against GDTL. [ABSTRACT FROM AUTHOR]

High yields of graphitic conical nanofibres (5-70 nm OD; <5 µm in length) are produced by pyrolysing various palladium precursors under an Ar atmosphere at 850-1000°C. The fibres exhibit diamond-shaped Pd particles at their tips, which are responsible for the carbon aggregation and its subsequent diffusion. This carbon replication phenomenon on the Pd particles results in the formation of stacked graphene cones, which grow aligned along a common axis, thus creating graphitic nanofibres. The cones within the fibres can be either open (lamp-shade type) or closed. The material has been analysed using sophisticated electron microscopy (HRTEM, SEM, ED) and spectroscopic techniques (Raman, EELS, EDX). Due to the large number of open edges, we envisage that these novel nanofibres may find important applications in the fabrication of field emitters, gas storage devices and composites. [ABSTRACT FROM PUBLISHER]

High yields of graphitic conical nanofibres (5-70 nm OD; <5 µm in length) are produced by pyrolysing various palladium precursors under an Ar atmosphere at 850-1000°C. The fibres exhibit diamond-shaped Pd particles at their tips, which are responsible for the carbon aggregation and its subsequent diffusion. This carbon replication phenomenon on the Pd particles results in the formation of stacked graphene cones, which grow aligned along a common axis, thus creating graphitic nanofibres. The cones within the fibres can be either open (lamp-shade type) or closed. The material has been analysed using sophisticated electron microscopy (HRTEM, SEM, ED) and spectroscopic techniques (Raman, EELS, EDX). Due to the large number of open edges, we envisage that these novel nanofibres may find important applications in the fabrication of field emitters, gas storage devices and composites. [ABSTRACT FROM AUTHOR]

The adhesion molecule CD44 is thought to play an important role in the inflammatory process. To identify the expression of CD44 in articular chondrocytes in rheumatoid arthritis (RA), monoclonal anti-CD44 antibodies were immunohistochemically used to react with articular cartilage specimens of 15 patients with RA, 9 with osteoarthritis (OA), and 6 with femoral neck fracture (FF). The proportion of CD44-positive chondrocytes in RA was 93 +/- 2% (N=16), which was significantly higher than that in OA (59 +/- 7%, N=9, p<0.001) and FF (46 +/- 5%, N=6, p<0.001). Among CD44 isoforms examined, the hemopoietic form was dominant in chondrocytes in RA. Therefore, up-regulation of CD44 on chondrocytes may play a significant role in cartilage degeneration in RA. [ABSTRACT FROM AUTHOR]

Examines chicken, Japanese quail, pigeon, duck and crow sera by a micro-scale serum neutralization test for the presence of virus-neutralizing (VN) antibodies to chicken anemia virus (CAV). Chickens as natural host of CAV; VN antibody in nine of 13 chicken flocks; Main symptoms of the disease; Absence of CAV in pigeons.