90 research outputs found

    Removal of nitrogen by Antarctic yeast cells at low temperature

    Get PDF
    Nitrate removal in a medium (at 5°C ) and the effect of culture temperature on the fatty acid composition were investigated using Candida sp. which was isolated from the upper layer of Lake Vanda in the McMurdo Dry Valleys, Antarctica. The strain was cultured at 5°C aerobically, on a synthetic medium containing potassium nitrate (NO_3-N, 100 mgl^) as a nitrogen source, and examined the effects of pH and chlorine on growth and NO_3-N removal in the medium. Within the pH of 3 to 7 the yeast cells exhibited a similar removal of nitrate level. The strain grew well and also removed nitrate at chlorine concentrations of 5 and 10 mgl^ but did not grow at chlorine concentration of 20 mgl^. Decreasing the growth temperature induced an increase in the content of linolenic acid (18:3) in the yeast cells

    Preparation of Rat Gingival Mitochondria with an Improved Isolation Method

    Get PDF
    In order to establish a method of obtaining rat gingival mitochondria (Mt), Mt fractions were prepared in various combinations of homogenizing time with collagenase concentration. Rat gingival tissues were excised, minced, treated with collagenase, homogenized, and subjected to differential centrifugation rates. Both the respiratory control ratio (RCR) and adenosine diphosphate/oxygen (ADP/O) ratio of the Mt fraction prepared in a combination of 40, 50, or 60 sec homogenization with collagenase in a concentration range of 0.115%–0.130% (w/v) were measured. The values for the RCR and ADP/O ratio of the Mt fraction obtained in an optimal condition was 1.80 ± 0.05 and 1.65 ± 0.03, respectively. These results suggest that Mt of fairly high quality can be obtained through this refined combination of the homogenizing time and collagenase concentration

    Development of Near Infrared-Fluorescent Nanophosphors and Applications for Cancer Diagnosis and Therapy

    Get PDF
    The use of near infrared (NIR) light for biomedical photonics in the wavelength region between 800 and 2000 nm, which is called “biological window”, has received particular attention since water and biological tissues have minimal optical loss due to scattering and absorption as well as autofluorescence in this region. Recent development of InGaAs CCD enables observations in this wavelength region. In the present paper, we report development of Yb and Er-doped yttrium oxide nanoparticles (Y2O3:YbEr-NP) which show strong NIR emission under NIR excitation (NIR-NIR emission). We also demonstrate that NIR emission can be observed through swine colon wall. Based on these results, we propose a possible application of Y2O3:YbEr-NP for cancer diagnosis and therapy using NIR-NIR imaging system. Our results also suggest potential applications of Y2O3:YbEr-NP for noninvasive detection of various diseases

    Association of Cardiovascular Health Metrics With Risk of Transition to Hypertension in Non-Hypertensive Young Adults

    Get PDF
    BACKGROUND The risk of developing hypertension in young adults and its relationship to modifiable lifestyle factors are unclear. We aimed to examine the association of cardiovascular health (CVH) metrics with the risk of hypertension. METHODS We analyzed 66,876 participants aged 20-39 years, with available blood pressure (BP) data for 5 consecutive years, who had normal or elevated BP at the initial health check-up, enrolled in the JMDC Claims Database. Ideal CVH metrics included nonsmoking, body mass inde

    Reduction in blood pressure for elevated blood pressure/stage 1 hypertension according to the American College of Cardiology/American Heart Association guideline and cardiovascular outcomes

    Get PDF
    Aims Few studies have examined the relationship of blood pressure (BP) change in adults with elevated BP or stage 1 hypertension according to the American College of Cardiology (ACC)/American Heart Association (AHA) guideline with cardiovascular outcomes. We sought to identify the effect of BP change among individuals with elevated BP or stage 1 hypertension on incident heart failure (HF) and other cardiovascular diseases (CVDs). Methods We conducted a retrospective cohort study including 616 483 individuals (median age 46 years, 73.7% men) with elevated and results BP or stage 1 hypertension based on the ACC/AHA BP guideline. Participants were categorized using BP classification at one-year as normal BP (n = 173 558), elevated BP/stage 1 hypertension (n = 367 454), or stage 2 hypertension (n = 75 471). The primary outcome was HF, and the secondary outcomes included (separately) myocardial infarction (MI), angina pectoris (AP), and stroke. Over a mean follow-up of 1097 ± 908 days, 10 544 HFs, 1317 MIs, 11 070 APs, and 5198 strokes were recorded. Compared with elevated BP/stage 1 hypertension at one-year, normal BP at one-year was associated with a lower risk of developing HF [hazard ratio (HR): 0.89, 95% CI:0.85–0.94], whereas stage 2 hypertension at one-year was associated with an elevated risk of developing HF (HR:1.43, 95% CI:1.36–1.51). This association was also present in other cardiovascular outcomes including MI, AP, and stroke. The relationship was consistent in all subgroups stratified by age, sex, baseline BP category, and overweight/obesity. Conclusion A one-year decline in BP was associated with the lower risk of HF, MI, AP, and stroke, suggesting the importance of lowering BP in individuals with elevated BP or stage 1 hypertension according to the ACC/AHA guideline to prevent the risk of developing CVD.</p

    Age-Dependent Association Between Modifiable Risk Factors and Incident Cardiovascular Disease

    Get PDF
    BACKGROUND: There have been limited data examining the age-dependent relationship of wide-range risk factors with the incidence of each subtype of cardiovascular disease (CVD) event. We assessed age-related associations between modifiable risk factors and the incidence of CVD. METHODS AND RESULTS: We analyzed 3 027 839 participants without a CVD history enrolled in the JMDC Claims Database (mean age, 44.8±11.0 years; 57.6% men). Each participant was categorized as aged 20 to 49 years (n=2 008 559), 50 to 59 years (n=712 273), and 60 to 75 years (n=307 007). Using Cox proportional hazards models and the relative risk reduction, we identified associations between risk factors and incident CVD, consisting of myocardial infarction, angina pectoris, stroke, and heart failure (HF). We assessed whether the association of risk factors for developing CVD would be modified by age cat-egory. Over a mean follow-up of 1133 days, 6315 myocardial infarction, 56 447 angina pectoris, 28 079 stroke, and 56 369 HF events were recorded. The incidence of myocardial infarction, angina pectoris, stroke, and HF increased with age category. Hazard ratios of obesity, hypertension, and diabetes in the multivariable Cox regression analyses for myocardial infarction, angina pectoris, stroke, and HF decreased with age category. The relative risk reduction of obesity, hypertension, and diabetes for CVD events decreased with age category. For example, the relative risk reduction of hypertension for HF decreased from 59.2% in participants aged 20 to 49 years to 38.1% in those aged 60 to 75 years. CONCLUSIONS: The contribution of modifiable risk factor to the development of CVD is greater in younger compared with older individuals. Preventive efforts for risk factor modification may be more effective in younger people.</p

    Close association of water channel AQP1 with amyloid-β deposition in Alzheimer disease brains

    Get PDF
    Aquaporin-1 (AQP1), a membrane water channel protein, is expressed exclusively in the choroid plexus epithelium in the central nervous system under physiological conditions. However, AQP1 expression is enhanced in reactive astrocytes, accumulating in brain lesions of Creutzfeldt-Jakob disease and multiple sclerosis, suggesting a role of AQP1-expressing astrocytes in brain water homeostasis under pathological conditions. To clarify a pathological implication of AQP1 in Alzheimer disease (AD), we investigated the possible relationship between amyloid-beta (Aβ) deposition and astrocytic AQP1 expression in the motor cortex and hippocampus of 11 AD patients and 16 age-matched other neurological disease cases. In all cases, AQP1 was expressed exclusively in a subpopulation of multipolar fibrillary astrocytes. The great majority of AQP1-expressing astrocytes were located either on the top of or in close proximity to Aβ plaques in AD brains but not in non-AD cases, whereas those independent of Aβ deposition were found predominantly in non-AD brains. By Western blot, cultured human astrocytes constitutively expressed AQP1, and the levels of AQP1 protein expression were not affected by exposure to Aβ1-42 peptide, but were elevated by hypertonic sodium chloride. By immunoprecipitation, the C-terminal fragment-beta (CTFβ) of amyloid precursor protein interacted with the N-terminal half of AQP1 spanning the transmembrane helices H1, H2 and H3. These observations suggest the possible association of astrocytic AQP1 with Aβ deposition in AD brains
    corecore