Microvasculature of Normal and Hydropic Labyrinth

The microvasculature of the inner ear in guinea pigs and humans was observed with a scanning electron microscope using corrosion casting method. Alterations in the inner ear vasculature which occurred in association with experimental endolymphatic hydrops were also investigated. The results thus obtained are summarized as follows: 1. In the cochlea and vestibule, the arteries, coiled arterioles, and the veins are endowed with their respective characteristic morphologic features and play a role in the regulatory mechanisms of circulation. 2. The point in humans which is most different from guinea pigs was that coiled arterioles in the cochlea and the coil-like traveling of the anterior vestibular artery is not outstanding. 3. Arteriovenous anastomoses were demonstrated to exist in lateral wall of cochlea and utricular macula, a finding suggesting the existence of a regulatory mechanism for local blood flow. 4. Endolymphatic hydrops was noted to be preferentially associated with vascular abnormalities in the lateral wall of the cochlear duct and in the saccular macula, among other vestibular structures

Regional optimum frequency analysis of resting-state fMRI data for early detection of Alzheimer’s disease biomarkers

The blood-oxygen label dependent (BOLD) signal obtained from functional magnetic resonance images (fMRI) varies significantly among populations. Yet, there is some agreement among researchers over the pace of the blood flow within several brain regions relative to the subject’s age and cognitive ability. Our analysis further suggested that regional coherence among the BOLD fMRI voxels belonging to the individual region of the brain has some correlation with underlying pathology as well as cognitive performance, which can suggest potential biomarkers to the early onset of the disease. To capitalise on this we propose a method, called Regional Optimum Frequency Analysis (ROFA), which is based on finding the optimum synchrony frequency observed at each brain region for each of the resting-state BOLD frequency bands (Slow 5 (0.01–0.027 Hz), Slow 4 (0.027–0.073 Hz) and slow 3 (0.073 to 0.198 Hz)), and the whole frequency band (0.01–0.167 Hz) respectively. The ROFA is carried out on fMRI data of total 310 scans, i.e., 26, 175 and 109 scans from 21 young-healthy (YH), 69 elderly-healthy (EH) and 33 Alzheimer’s disease (AD) patients respectively, where these scans include repeated scans from some subjects acquired at 3 to 6 months intervals. A 10-fold cross-validation procedure evaluated the performance of ROFA for classification between the YH vs EH, YH vs AD and EH vs AD subjects. Based on the confusion-matrix parameters; accuracy, precision, sensitivity and Matthew’s correlation coefficient (MCC), the proposed ROFA classification outperformed the state-of-the-art Group-independent component analysis (Group-ICA), Functional-connectivity, Graph metrics, Eigen-vector centrality, Amplitude of low-frequency fluctuation (ALFF) and fractional amplitude of low-frequency fluctuations (fALFF) based methods with more than 94.99% precision and 95.67% sensitivity for different subject groups. The results demonstrate the effectiveness of the proposed ROFA parameters (frequencies) as adequate biomarkers of Alzheimer’s disease

Genotoxicity of styrene oligomers extracted from polystyrene intended for use in contact with food

AbstractHere, we conducted in vitro genotoxicity tests to evaluate the genotoxicity of styrene oligomers extracted from polystyrene intended for use in contact with food. Styrene oligomers were extracted with acetone and the extract was subjected to the Ames test (OECD test guideline No. 471) and the in vitro chromosomal aberration test (OECD test guideline No. 473) under good laboratory practice conditions. The concentrations of styrene dimers and trimers in the concentrated extract were 540 and 13,431 ppm, respectively. Extraction with acetone provided markedly higher concentrations of styrene oligomers compared with extraction with 50% ethanol aqueous solution, which is the food simulant currently recommended for use in safety assessments of polystyrene by both the United States Food and Drug Administration and the European Food Safety Authority. And these high concentrations of styrene dimers and trimers were utilized for the evaluation of genotoxicity in vitro. Ames tests using five bacterial tester strains were negative both in the presence or absence of metabolic activation. The in vitro chromosomal aberration test using Chinese hamster lung cells (CHL/IU) was also negative. Together, these results suggest that the risk of the genotoxicity of styrene oligomers that migrate from polystyrene food packaging into food is very low

Mesurement of Cyanide-Resistant Respiration in Leaf Blade of Rice by Use of Oxygen Isotope Discrimination

A reduction in the dark respiration of rice may improve dry-matter production and yield. To explore the possibility of controlling cyanide-resistant alternative respiration, of which energy production efficiency is low, we constructed a measuring system for cyanide-resistant respiration in leaf blades of rice with the use of oxgen isotope discrimination. Dark respiration was lowest at 10mM KCN, the inhibitor of cytochrome pathway, and it was lowest at 30mM salicylhydroxamic acid (SHAM), the inhibitor of the alternative pathway. Oxygen isotope discrimination was highest when leaf blade had HCN applied for 1 hour after being soaked in 10mM KCM for 3 minutes, and it was lowest when lowest when leaf blade was soaked in 30mM SHAM regardless of the soaking method. The discrimination factors of the alternative oxidase and the cytochrome oxidase of leaf blade were estimination factors of the alternative oxidase and the cytochrome oxidase of leaf blade were estimated as 20.3‰ and 13.9‰, respectively, and the ratio of cyanide-resistant respiration to dark respiration of leaf blade was 38%.イネの暗呼吸の抑制は乾物生産や収量の増大に貢献すると考えられている．エネルギー生産効率の低いシアン耐性呼吸の抑制の可能性を検討するため，酸素同位体分別を利用したシアン耐性呼吸の測定装置を製作し，イネ葉身の測定法を検討した．その結果，葉身の暗呼吸速度はシトクロム経路の阻害剤であるKCN溶液の濃度が10mMのときに，また，シアン耐性呼吸経路の阻害剤であるSHAM溶液の濃度が30mMのときに低下が最大であった．分別係数は３分間10mM KCN溶液に浸漬後HCNに１時間さらした場合に最も高い20.3‰が得られた．いっぽう，SHAM処理では30mMの溶液であれば浸漬法にかかわらず，13.9‰であった．これらから，イネ葉身のオルターティブ酸化酵素とシトクロム酸化酵素の分別係数はそれぞれ20.3‰と13.9‰であると推定され，このときのシアン耐性呼吸の割合は38%であった

Changes of bone mineral densities in women and prevention and treatment of osteoporosis

当科では3年ほど前よりQCT法を用いて骨塩量測定を行い,骨粗鬆症の管理治療を行っている｡264名の測定値について分析をしたところ,40歳頃から60歳にかけて急速に低下すること,肥満度が増すにつれ骨塩量も増加する傾向がみられた｡また,閉経前に卵巣を両側摘出した場合ホルモン補充療法を行っているが,卵巣を温存した場合と差がでなかった｡治療に結合型エストロゲンを用いた群の12カ月後の骨塩量の増加率は,任用しなかった群にくらべ有意の差があった｡Bone mineral density (BMD) was measured in 264 females by QCT. BMD was rapidly decreased between 40's and 60's. There was a tendency for BMD increase in proportion to obesity. HRT was made without bilateral ovaries at operation, then there were no differencis between removal of ovaries and preserve of ovaries. The increase rate of BMD treated by conjugated-estrogens was higher than that of no treated BMD (p<0.05)