An exact collisionless equilibrium for the Force-Free Harris Sheet with low plasma beta

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allanson, O., E-mail: oliver.allanson@st-andrews.ac.uk; Neukirch, T., E-mail: tn3@st-andrews.ac.uk; Wilson, F., E-mail: fw237@st-andrews.ac.uk

We present a first discussion and analysis of the physical properties of a new exact collisionless equilibrium for a one-dimensional nonlinear force-free magnetic field, namely, the force-free Harris sheet. The solution allows any value of the plasma beta, and crucially below unity, which previous nonlinear force-free collisionless equilibria could not. The distribution function involves infinite series of Hermite polynomials in the canonical momenta, of which the important mathematical properties of convergence and non-negativity have recently been proven. Plots of the distribution function are presented for the plasma beta modestly below unity, and we compare the shape of the distribution functionmore » in two of the velocity directions to a Maxwellian distribution.« less

Need for beta-blockade in hypertension reduced with long-term minoxidil.

PubMed Central

Brunner, H R; Jaeger, P; Ferguson, R K; Jequier, E; Turini, G; Gavras, H

1978-01-01

Sequential changes in plasma renin activity and urinary aldosterone and noradrenaline were assessed in eight patients with severe hypertension after minoxidil had been added to their treatment. Doses of 2.5--27.5 (mean 12.5) mg/day reduced the mean blood pressure from 166/113 +/-6/2 mm Hg to 124/88+/-4/2 mm Hg in one week. Plasma renin activity and urinary aldosterone and noradrenaline increased twofold to threefold initially but returned to baseline values within two to three weeks and remained unchanged during a mean follow-up of 5.1 months. Beta-blocking drugs were then withdrawn slowly in six patients without adverse effects, though blood pressure and heart rate increased in three patients, who required minimal doses of beta-blockers. Plasma renin activity and urinary aldosterone and noradrenaline did not change significantly after beta-blockade had been stopped. We conclude that the need for beta-blockade is greatly reduced with long-term minoxidil treatment and that it may be unnecessary in some patients. PMID:28811

Steroid determination in fish plasma using capillary electrophoresis.

PubMed

Bykova, Liliya; Archer-Hartmann, Stephanie A; Holland, Lisa A; Iwanowicz, Luke R; Blazer, Vicki S

2010-09-01

A capillary separation method that incorporates pH-mediated stacking is employed for the simultaneous determination of circulating steroid hormones in plasma from Perca flavescens (yellow perch) collected from natural aquatic environments. The method can be applied to separate eight steroid standards: progesterone, 17alpha,20beta-dihydroxypregn-4-en-3-one, 17alpha-hydroxyprogesterone, testosterone, estrone, 11-ketotestosterone, ethynyl estradiol, and 17beta-estradiol. Based on screening of plasma, the performance of the analytical method was determined for 17alpha,20beta-dihydroxypregn-4-en-3-one, testosterone, 11-ketotestosterone, and 17beta-estradiol. The within-day reproducibility in migration time for these four steroids in aqueous samples was < or =2%. Steroid quantification was accomplished using a calibration curve obtained with external standards. Plasma samples from fish collected from the Choptank and Severn Rivers, Maryland, USA, stored for up to one year were extracted with ethyl acetate and then further processed with anion exchange and hydrophobic solid phase extraction cartridges. The recovery of testosterone and 17beta-estradiol from yellow perch plasma was 84 and 85%, respectively. Endogenous levels of testosterone ranged from 0.9 to 44 ng/ml, and when detected 17alpha,20beta-dihydroxypregn-4-en-3-one ranged from 5 to 34 ng/ml. The reported values for testosterone correlated well with the immunoassay technique. Endogenous concentrations of 17beta-estradiol were < or =1.7 ng/ml. 11-Ketotestosterone was not quantified because of a suspected interferant. Higher levels of 17alpha,20beta-dihydroxypregn-4-en-3-one were found in male and female fish in which 17beta-estradiol was not detected. Monitoring multiple steroids can provide insight into hormonal fluctuations in fish. Copyright 2010 SETAC.

Kinetics of the epimeric glucocorticoid budesonide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ryrfeldt, A.; Edsbaecker, S.; Pauwels, R.

1984-04-01

Budesonide is a potent nonhalogenated glucocorticoid consisting of a 1/1 mixture of the two epimers 22R and 22S. The kinetics of these epimers were studied in six healthy male subjects after intravenous administration of 500 micrograms /sup 3/H-budesonide. Estimation of the epimer concentrations in plasma was made possible by development of an HPLC method for simultaneous separation and quantification. The plasma t 1/2, distribution volume (V beta), and plasma clearance for epimer 22R were (mean +/- SD) 2.66 +/- 0.57 hr, 425 +/- 100 l, and 117 +/- 40 l/hr. The corresponding values for epimer 22S were 2.71 +/- 0.69more » hr, 245 +/- 38 l, and 67 +/- 19 l/hr. Differences in V beta and plasma clearance between the two were significant. The larger V beta noted for epimer 22R may be a result of higher tissue affinity. The high plasma clearance for both epimers should largely reflect their high rate of liver biotransformation.« less

Evaluation of thrombogenicity of beta-propiolactone/ultraviolet (beta-PL/UV) treated PPSB in chimpanzees

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kotitschke, R.; Stephan, W.; Prince, A.M.

1983-05-01

The thrombogenicity of beta-PL/UV-treated PPSB (factor IX concentrate) was evaluated in chimpanzees. PPSB isolated from beta-propiolactone-treated and UV-irradiated plasma was injected into chimpanzees at a dose of approximately 100 units/kg body weight. An FDA licensed PPSB preparation served as the negative control, and a preparation containing activated as well as precursor clotting factors served as the positive control. 15 minutes, 1 h, 4 h, and 24 h after the PPSB application the following parameters were determined in the chimpanzee blood: factors II, VII, IX, X, VIII, fibrinogen, AT III, thrombin coagulase, Quick value, APTT and platelet count. Neither the untreatedmore » control preparation, nor the PPSB isolated from beta-propiolactone-treated and UV-irradiated plasma, showed signs of thrombogenicity in the chimpanzee model. The positive control indicated that the chimpanzee is a suitable model for the thrombogenicity testing of activated clotting factors.« less

3,4-Methylenedioxymethamphetamine (MDMA) abuse may cause oxidative stress and potential free radical damage.

PubMed

Zhou, Jun F; Chen, Peng; Zhou, Ye H; Zhang, Liang; Chen, Huai H

2003-05-01

To investigate whether 3,4-methylenedioxymethamphetamine abuse (MDMA abuse) may cause oxidative stress and potential free radical damage in the bodies of MDMA abusers (MA), and to explore the mechanisms by which MDMA abuse may be causing oxidative stress. One hundred and twenty MA and 120 healthy volunteers (HV) were enrolled in a random control study design, in which the level of lipoperoxide (LPO) in erythrocytes, and the levels of Vitamin C (VC), Vitamin E (VE) and beta-carotene (beta-CAR) in plasma as well as the activities of superoxide dismutase (SOD) and catalase (CAT) in erythrocytes were determined by spectrophotometric methods. Compared with the average values of the above biochemical parameters in the HV group, the average value of LPO in erythrocytes in the MA group was significantly increased (P < 0.0001), while the average values of VC, VE and beta-CAR in plasma as well as those of SOD and CAT in erythrocytes in the MA group were significantly decreased (P < 0.0001). The analysis of bivariate correlations suggested that with the increase of the MDMA abuse dose and the MDMA abuse duration, the level of LPO in erythrocytes in the MA was increased (P < 0.0001), while the levels of VC, VE and beta-CAR in plasma as well as the activities of SOD and CAT in erythrocytes in the MA were decreased (P < 0.0001). The findings in this study suggest that MDMA abuse may cause oxidative stress and potential free radical damage to MA.

The Role of Compressibility in Energy Release by Magnetic Reconnection

NASA Technical Reports Server (NTRS)

Birn, J.; Borovosky, J. E.; Hesse, M.

2012-01-01

Using resistive compressible magnetohydrodynamics, we investigate the energy release and transfer by magnetic reconnection in finite (closed or periodic) systems. The emphasis is on the magnitude of energy released and transferred to plasma heating in configurations that range from highly compressible to incompressible, based on the magnitude of the background beta (ratio of plasma pressure over magnetic pressure) and of a guide field in two-dimensional reconnection. As expected, the system becomes more incompressible, and the role of compressional heating diminishes, with increasing beta or increasing guide field. Nevertheless, compressional heating may dominate over Joule heating for values of the guide field of 2 or 3 (in relation to the reconnecting magnetic field component) and beta of 5-10. This result stems from the strong localization of the dissipation near the reconnection site, which is modeled based on particle simulation results. Imposing uniform resistivity, corresponding to a Lundquist number of 10(exp 3) to 10(exp 4), leads to significantly larger Ohmic heating. Increasing incompressibility greatly reduces the magnetic flux transfer and the amount of energy released, from approx. 10% of the energy associated with the reconnecting field component, for zero guide field and low beta, to approx. 0.2%-0.4% for large values of the guide field B(sub y0) > 5 or large beta. The results demonstrate the importance of taking into account plasma compressibility and localization of dissipation in investigations of heating by turbulent reconnection, possibly relevant for solar wind or coronal heating.

Simple and sensitive HPLC method with fluorescence detection for the measurement of ibuprofen in rat plasma: application to a long-lasting dosage form.

PubMed

Hassan, Ahmed Sheikh; Sapin, Anne; Ubrich, Nathalie; Maincent, Philippe; Bolzan, Claire; Leroy, Pierre

2008-10-01

A simple and sensitive high-performance liquid chromatography (HPLC) assay applied to the measurement of ibuprofen in rat plasma has been developed. Two parameters have been investigated to improve ibuprofen detectability using fluorescence detection: variation of mobile phase pH and the use of beta-cyclodextrin (beta-CD). Increasing the pH value from 2.5 to 6.5 and adding 5 mM beta-CD enhanced the fluorescence signal (lambda(exc) = 224 nm; lambda(em) = 290 nm) by 2.5 and 1.3-fold, respectively, when using standards. In the case of plasma samples, only pH variation significantly lowered detection and quantification limits, down to 10 and 35 ng/mL, respectively. Full selectivity was obtained with a single step for plasma treatment, that is, protein precipitation with acidified acetonitrile. The validated method was applied to a pharmacokinetic study of ibuprofen encapsulated in microspheres and subcutaneously administered to rats.

[Effects of electroacupuncture on bispectral index and plasma beta-endorphin in patients undergoing colonoscopy].

PubMed

Ni, Yu-Fei; Li, Jun; Wang, Ben-Fu; Jiang, Song-He; Chen, Yi; Zhang, Wei-Feng; Lian, Qing-Quan

2009-10-01

To observe the effect of electroacupuncture (EA) on bispectral index (BIS) and plasma beta-endorphin (beta-EP) level in patients undergoing colonoscopy. Sixty patients were equally randomized into EA group and control group with 30 cases in each. EA (2 Hz/100 Hz, 4-6 V) was applied to the right Zusanli (ST 36) and Shangjuxu (ST 37), and the left Yinlingquan (SP 9), Sanyinjiao (SP 6) and bilateral Hegu (LI 4) respectively 30 min before colonoscopy. The mean arterial pressure (MAP), heart rate (HR) and BIS in two groups were continuously monitored during the study. Plasma beta-EP concentration was detected by radioimmunoassay. The patient's adverse reactions (including pain, satisfaction degree, etc.) were evaluated by visual analog scale (VAS) and verbal stress scale (VSS). Self-comparison showed that MAP and HR in control group increased significantly during colonoscope's splenic flexure passing (P<0.05). Whereas the 2 indexes in EA group had no significant changes during colonoscope insertion, and its splenic flexure passing, hepatic flexure passing and post-enteroscopy (P>0.05). Comparison between two groups showed that MAP at the time-point of colonoscope insertion, and HR at the time-point of colonoscope's splenic flexure passing in EA group were significantly lower than those in control group (P<0.05). BIS values of EA group were significantly lower than those of control group at different time-points after colonoscope insertion (P<0.01). Plasma beta-EP concentrations at the time-points of colonoscope's hepatic flexure passing and post-enteroscopy were evidently increased in both groups in comparison with pre-enteroscopy (P<0.01), and beta-EP was significantly lower in EA group than that in control group at the time-point of colonoscope's hepatic flexure passing (P<0.05). The dosage of Midazolam used for conscious-sedation and the scores of VAS and VSS were also considerably lower in EA group than those in control group (P<0.05, P<0.01). No significant differences were found between two groups in the adverse reactions as dizziness, nausea, vomiting and abdominal pain, but the patients' satisfaction degree in EA group was evidently higher than that in control group (P<0.05). Acupuncture analgesia can effectively lower the colonoscopy patients' BIS value and plasma beta-EP level, meaning attenuation of the patients' stress responses during colonoscopy after EA.

Oestrogen and progesterone concentrations in plasma and oviductal tissue of ewes exhibiting a natural or induced oestrus.

PubMed

Theodosiadou, E; Goulas, P; Kouskoura, Th; Smokovitis, A

2004-01-01

Synchronisation of oestrus in Karagouniki ewes by administration of the standard dose of progesterone results in lower fertility than observed when these ewes ovulate naturally. This suggests that the optimum dose of progesterone may be breed dependent. The exogenous progesterone may perturb the concentrations of oestradiol-17beta and progesterone in blood plasma and the oviductal wall. This possibility was investigated using Karagouniki ewes allocated at random to three treatments (n=4 per treatment). Ewes were allowed to exhibit natural oestrus (N) or oestrus was synchronised by administration of 250 mg (LP) or 375 mg (HP) progesterone (subcutaneous implants) followed by PMSG at 8 mg/kg live weight i.m. 14 days later. Oestrus was observed using teaser rams. Blood samples were collected for plasma oestradiol-17beta and progesterone assay from the onset to the end of oestrus at 2 h intervals. The uterus of each ewe was recovered at the end of oestrus and samples of the oviductal wall were taken from both oviducts and prepared, separately, for progesterone and oestradiol-17beta assay. Statistical analysis was performed using univariate analysis of variance. Plasma oestradiol-17beta concentrations from the onset to the end of oestrus were highest for N ewes and lowest for HP ewes with the values for LP ewes occupying an intermediate position. The differences were significant (P<0.05) between HP and the other two treatments from 4 to 12 h after the onset of oestrus and then between all treatments until the end of oestrus. Plasma progesterone levels were similar and fairly constant from the onset to the end of oestrus for N and LP. The plasma progesterone levels for HP were significantly (P<0.05) higher than for the other two treatments throughout oestrus. In oviductal wall samples, the oestradiol-17beta concentration was significantly (P<0.05) higher for N ewes than for synchronised ewes and the levels were similar for LP and HP ewes. The concentration of oestradiol-17beta differed (P<0.05) between right and left oviducts for N ewes but not for ewes of either of the synchronised oestrus treatments. Progesterone concentrations in oviductal wall samples were highest (P<0.05) for HP ewes and the values for N and LP ewes were similar. The concentration of progesterone did not differ between right and left oviductal wall samples within treatments. It was concluded that the higher dose of exogenous progesterone perturbed the levels of oestradiol-17beta and progesterone in blood plasma and the oviductal wall, and this could explain the lower levels of fertility (relative to naturally occurring oestrus) observed when this protocol is used for Karagouniki ewes in practice.

Plasma beta-carotene is not a suitable biomarker of fruit and vegetable intake in german subjects with a long-term high consumption of fruits and vegetables.

PubMed

Garcia, A L; Mohan, R; Koebnick, C; Bub, A; Heuer, T; Strassner, C; Groeneveld, M J; Katz, N; Elmadfa, I; Leitzmann, C; Hoffmann, I

2010-01-01

beta-Carotene is often used as a marker for the amount of fruit and vegetables consumed, but little is known about plasma beta-carotene concentrations in subjects whose habitual (long-term) diets are characterized by different amounts of foods of plant origin. We compared dietary beta-carotene intake and plasma concentrations in women on habitual diets differing in the consumed amounts of foods of plant origin. A comparison of dietary beta-carotene intakes and plasma beta-carotene concentrations in women adhering to an average Western diet (n = 172), wholesome nutrition (following preventive recommendations) (n = 238) or a raw food diet (n = 104). Dietary beta-carotene intake was 5.5, 9.3, 14.7 mg/day for women adhering to an average Western diet, wholesome nutrition and raw food diet, respectively (p < 0.001). Corresponding multivariate adjusted plasma beta-carotene concentrations were 1.07, 1.65, and 1.16 micromol/l, respectively (p < 0.001). Comparable dietary beta-carotene intake resulted in lower multivariate adjusted plasma beta-carotene in women adhering to a raw food diet and average Western diet compared to those on wholesome nutrition (p < 0.001 for all intake groups up to 20 mg/day). The amount of fruit and vegetable intake did not predict plasma beta-carotene levels in women consuming a raw food diet. Plasma beta-carotene concentrations differed among the diet groups, with highest plasma levels in women adhering to wholesome nutrition. Plasma beta-carotene concentrations may not reflect beta-carotene intake and the amount of fruit and vegetables consumed. 2009 S. Karger AG, Basel.

Marginal instability threshold condition of the aperiodic ordinary mode in equal-mass plasmas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vafin, S.; Schlickeiser, R.; Yoon, P. H.

The purely growing ordinary (O) mode instability for counter-streaming bi-Maxwellian plasma particle distribution functions has recently received renewed attention due to its importance for the solar wind plasma. Here, the analytical marginal instability condition is derived for magnetized plasmas consisting of equal-mass charged particles, distributed in counter-streams with equal temperatures. The equal-mass composition assumption enormously facilitates the theoretical analysis due to the equality of the values of the electron and positron (positive and negative ion) plasma and gyrofrequencies. The existence of a new instability domain of the O-mode at small plasma beta values is confirmed, when the parallel counter-stream freemore » energy exceeds the perpendicular bi-Maxwellian free energy.« less

Maternal serum free-beta-chorionic gonadotrophin, pregnancy-associated plasma protein-A and fetal nuchal translucency thickness at 10-13(+6) weeks in relation to co-variables in pregnant Saudi women.

PubMed

Ardawi, Mohammed-Salleh M; Nasrat, Hasan A; Rouzi, Abdulrahim A; Qari, Mohammed H; Al-Qahtani, Mohammed H; Abuzenadah, Adel M

2007-04-01

To establish normative values and distribution parameters of first-trimester screening markers, namely, fetal nuchal translucency (NT), maternal serum free beta-human chorionic gonadotrophin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A), at 10 to 13(+6) weeks of gestation in Saudi women and to evaluate the effect of co-variables including maternal body weight, gravidity, parity, fetal gender, twin pregnancy, smoking and ethnicity on these markers. A cohort of Saudi women (first cohort n = 1616) with singleton pregnancies prospectively participated in the present study, and fetal NT together with maternal serum free beta-hCG and PAPP-A were determined at 10 to 13(+6) weeks of gestation. The distribution of gestational age-independent multiples of the median (MoM) of the parameters was defined and normative values were established, and correction for maternal body weight was made accordingly. The influence of various co-variables was examined using the data collected from the first and the second (n = 1849) cohorts of women and 62 twin pregnancies, and compared with other studies. All markers exhibited log-normally distributed MoMs. Gestational age-independent normative values were established. Maternal body weight was corrected, particularly for maternal free beta-hCG and PAPP-A using standard methods. Fetal NT showed a negative relationship with increasing gravidity (r = -0.296) or parity (r = -0.311), whereas both free beta-hCG and PAPP-A exhibited a significant positive relationship. There was a significant increase in the MoM of free beta-hCG in female fetuses. Smoking decreased MoM values of free beta-hCG (by 14.6%; P < 0.01) and PAPP-A (by 18.8%; P < 0.001). Twin pregnancy showed significant increases in MoM values of free beta-hCG (by 1.87-fold) and PAPP-A (by 2.24-fold), with no significant changes in fetal NT MoM values. Fetal NT MoM values were lower in Africans and Asians but higher in Orientals, as compared to Saudi women (P < 0.05; in each case). MoM values (body weight-corrected) of free beta-hCG were 25.2% higher in Africans and 19.4% higher in Orientals but 6.8% lower in other Arabian and Asian (by 5.8%) women as compared to Saudi women (P < 0.05; in each case). The normative values and distribution parameters for fetal NT, maternal serum free beta-hCG and PAPP-A were established in Saudi singleton pregnancies, the maternal body weight together with smoking, twin pregnancy and ethnicity being important first-trimester screening co-variables. Gravidity, parity and fetal gender are also considered to influence one or more of the first-trimester markers examined. Copyright (c) 2007 John Wiley & Sons, Ltd.

Fast ion beta limit measurements by collimated neutron detection in MST plasmas

NASA Astrophysics Data System (ADS)

Capecchi, William; Anderson, Jay; Bonofiglo, Phillip; Kim, Jungha; Sears, Stephanie

2015-11-01

Fast ion orbits in the reversed field pinch (RFP) are well ordered and classically confined despite magnetic field stochasticity generated by multiple tearing modes. Classical TRANSP modeling of a 1MW tangentially injected hydrogen neutral beam in MST deuterium plasmas predicts a core-localized fast ion density that can be up to 25% of the electron density and a fast ion beta of many times the local thermal beta. However, neutral particle analysis of an NBI-driven mode (presumably driven by a fast ion pressure gradient) shows mode-induced transport of core-localized fast ions and a saturated fast ion density. The TRANSP modeling is presumed valid until the onset of the beam-driven mode and gives an initial estimate of the volume-averaged fast ion beta of 1-2% (local core value up to 10%). A collimated neutron detector for fusion product profile measurements will be used to determine the spatial distribution of fast ions, allowing for a first measurement of the critical fast-ion pressure gradient required for mode destabilization. Testing/calibration data and initial fast-ion profiles will be presented. Characterization of both the local and global fast ion beta will be done for deuterium beam injection into deuterium plasmas for comparison to TRANSP predictions. Work supported by US DOE.

Plasma beta-endorphin levels in obese and non-obese patients with polycystic ovary disease.

PubMed

Martínez-Guisasola, J; Guerrero, M; Alonso, F; Díaz, F; Cordero, J; Ferrer, J

2001-02-01

The aim of this study was to determine the influence of body weight on circulating plasma levels of beta-endorphin and insulin in women with polycystic ovary disease (PCOD), as well as the correlation between the plasma levels of beta-endorphin and insulin. One-hundred and sixty-seven consecutive subjects with PCOD were recruited, 117 of whom had normal weight (body mass index (BMI) < 25) while 50 were obese (BMI > 25). A venous blood sample was taken and plasma concentrations of beta-endorphin, insulin, gonadotropins, prolactin, progesterone, 17 beta-estradiol, estrone, androgens, dehydroepiandrosterone sulfate and sex hormone-binding globulin (SHBG) were measured. Mean beta-endorphin and insulin plasma levels were significantly higher (p < 0.05) in obese PCOD women than in non-obese ones. Correlation analysis showed a positive association between insulin and beta-endorphin, beta-endorphin and BMI (and weight), insulin and BMI (and weight), and a negative correlation was found between insulin and SHBG. A weak association was found between beta-endorphin and luteinizing hormone (LH) in peripheral plasma. Stratified and linear regression analysis showed that plasma beta-endorphin concentrations correlate more with BMI than with insulinemia.

11beta-hydroxysteroid dehydrogenase in the testis of Bufo arenarum: changes in its seasonal activity.

PubMed

Denari, Daniela; Ceballos, Nora R

2005-09-01

In rat Leydig cells, glucocorticoids (GC) inhibit testosterone (T) synthesis via glucocorticoid receptor (GR). However, GC access to GR is regulated by the local expression of 11beta-hydroxysteroid dehydrogenase (11beta-HSD). Two isoforms were identified in mammals: type 1, a NADP+-preferring enzyme with K(m) in the muM range for GC and type 2, NAD+-dependent, with K(m) in the nM range for GC. In amphibians, a seasonal rhythm in baseline GC levels was described. However, a shift in the amount of deactivating 11beta-HSD activity could alter GC effects. The purpose of this work is to describe seasonal changes in testicular activity of 11beta-HSD in Bufo arenarum as well as the annual and seasonal patterns of plasma corticosterone (B) and T. The activity of 11beta-HSD was assayed in homogenate and subcellular fractions in pre-reproductive (Pre-R), reproductive (R) and post-reproductive (Post-R) periods, using [3H]B. Plasma B and T were determined by RIA. Testicular 11beta-HSD is a microsomal NAD+-dependent enzyme with a K(m) in the nM order, its activity being strongly reduced by glycyrrhetinic acid. These results indicate that toad testes express an 11beta-HSD similar to mammalian type 2. Although 11beta-HSD activity is higher in the Post-R than in the R and Pre-R seasons (V(max): Pre-R: 0.26+/-0.10, R: 0.14+/-0.01, Post-R: 1.37+/-0.45, pmol/minmg protein), K(m) value remains constant throughout the year. A seasonal rhythm in baseline GC concentrations inversely correlated with plasma T was also described. T concentration is lower in the R season than in the other periods (Pre-R: 90+/-6; R: 12+/-1; Post-R: 56+/-3, nM) while total B concentration is higher in the breeding than in the other seasons (Pre-R: 62+/-10; R: 145+/-18; Post-R: 96+/-10, nM). Furthermore, free B (Pre-R: 51+/-8; R: 94+/-12; Post-R: 70+/-7, nM) was always below K(m) values. In conclusion, this work shows that the activity of 11beta-HSD in toad testes could modulate GC action by transforming active hormones in the corresponding inactive steroid.

Longitudinal waves in a perpendicular collisionless plasma shock. IV - Gradient B.

NASA Technical Reports Server (NTRS)

Gary, S. P.

1972-01-01

The consideration of elastic waves in a Vlasov plasma of unmagnetized ions and magnetized electrons undergoing E x B electron drift and gradient B drift, pursued in the earlier three parts, is brought to conclusion in this last part of the longitudinal wave study in a collisionless plasma shock. Detailed calculations of the effects of the beta sub e dimensionless parameter on the E x B electron drift instability are presented. It is shown that the range of propagation of the elastic waves about the perpendicular remains quite narrow, and that, for oblique propagation, the already narrow angular range of unstable waves is decreased by increases in the value of the beta sub e dimensionless parameter. Also, increases in wave number generally reduce the growth rate and the angular range of propagation.

Plasma immunoreactive beta-melanocyte-stimulating hormone and skin pigmentation in chronic renal failure.

PubMed Central

Smith, A G; Shuster, S; Comaish, J S; Plummer, N A; Thody, A J; Alvarez-Ude, F; Kerr, D N

1975-01-01

Plasma immunoreactive beta-melanocyte stimulating hormone (beta-MSH) concentrations were greatly increased in patients with chronic renal failure. There was no correlation between the severity of the renal failure or the degree of pigmentation and the plasma beta-MSH levels. PMID:1125653

Is plasma {beta}-glucuronidase a novel human biomarker for monitoring anticholinesterase pesticides exposure? A Malaysian experience

DOE Office of Scientific and Technical Information (OSTI.GOV)

Inayat-Hussain, Salmaan H.; Lubis, Syarif Husin; Sakian, Noor Ibrahim Mohamed

A cross-sectional study was conducted to investigate the effects of acute and chronic pesticide exposure on the plasma {beta}-glucuronidase enzyme activity among five patients of acute pesticide poisoning in Tengku Ampuan Rahimah Hospital, Klang, 230 farmers in the MADA area, Kedah and 49 fishermen in Setiu, Terengganu. The duration of pesticide exposure among the patients was unknown, but the plasma samples from patients were collected on day one in the hospital. The duration of pesticide exposure among the farmers was between 1 and 45 years. The {beta}-glucuronidase activity was compared with plasma cholinesterase activity in the same individual. The plasmamore » cholinesterase activity was measured using Cholinesterase (PTC) Reagent set kit (Teco Diagnostics, UK) based on colorimetric method, while the plasma {beta}-glucuronidase activity was measured fluorometrically based on {beta}-glucuronidase assay. The plasma cholinesterase activity was significantly reduced (p < 0.05) among the patients (1386.786 {+-} 791.291 U/L/min) but the inhibition in plasma cholinesterase activity among the farmers (7346.5 {+-} 1860.786 U/L/min) was not significant (p > 0.05). The plasma {beta}-glucuronidase activity among the farmers was significantly elevated (p < 0.05) (0.737 {+-} 0.425 {mu}M/h) but not significant among the patients (p > 0.05). The plasma cholinesterase activity was positively correlated with the plasma {beta}-glucuronidase activity among the farmers (r = 0.205, p < 0.01) but not among the patients (r = 0.79, p > 0.05). Thus, plasma {beta}-glucuronidase enzyme activity can be measured as a biomarker for the chronic exposure of pesticide. However, further studies need to be performed to confirm whether plasma {beta}-glucuronidase can be a sensitive biomarker for anticholinesterase pesticide poisoning.« less

High-beta steady-state research with integrated modeling in the JT-60 Upgrade

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ozeki, T.

2007-05-15

Improvement of high-beta performance and its long sustainment was obtained with ferritic steel tiles in the JT-60 Upgrade (JT-60U) [T. Fujita et al., Phys. Plasmas 50, 104 (2005)], which were installed inside the vacuum vessel to reduce fast ion loss by decreasing the toroidal field ripple. When a separation between the plasma surface and the wall was small, high-beta plasmas reached the ideal wall stability limit, i.e., the ideal magnetohydrodynamics stability limit with the wall stabilization. A small rotation velocity of 0.3% of the Alfven velocity was found to be effective for suppressing the resistive wall mode. Sustainment of themore » high normalized beta value of {beta}{sub N}=2.3 has been extended to 28.6 s ({approx}15 times the current diffusion time) by improvement of the confinement and increase in the net heating power. Based on the research in JT-60U experiments and first-principle simulations, integrated models of core, edge-pedestal, and scrape-off-layer (SOL) divertors were developed, and they clarified complex features of reactor-relevant plasmas. The integrated core plasma model indicated that the small amount of electron cyclotron (EC) current density of about half the bootstrap current density could effectively stabilize the neoclassical tearing mode by the localized EC current accurately aligned to the magnetic island center. The integrated edge-pedestal model clarified that the collisionality dependence of energy loss due to the edge-localized mode was caused by the change in the width of the unstable mode and the SOL transport. The integrated SOL-divertor model clarified the effect of the exhaust slot on the pumping efficiency and the cause of enhanced radiation near the X-point multifaceted asymmetric radiation from edge. Success in these consistent analyses using the integrated code indicates that it is an effective means to investigate complex plasmas and to control the integrated performance.« less

System and method of operating toroidal magnetic confinement devices

DOEpatents

Chance, M.S.; Jardin, S.C.; Stix, T.H.; Grimm, R.C.; Manickam, J.; Okabayashi, M.

1984-08-30

This invention pertains to methods and arrangements for attaining high beta values in plasma confinement devices. More specifically, this invention pertains to methods for accessing the second stability region of operation in toroidal magnetic confinement devices.

Effect of beta-endorphin imprinting during late pregnancy on the brain serotonin and plasma nocistatin levels of adult male rats.

PubMed

Tekes, K; Gyenge, M; Hantos, M; Csaba, G

2007-07-01

Female rats were treated with 10 microg of beta-endorphin on the 19th day of pregnancy. Offspring were studied when five months old. Serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) content in four brain regions were determined by HPLC-EC and the nocistatin levels of blood plasma using RIA methods. In each brain region studied, the 5-HT levels were highly significantly reduced and that of 5-HIAA in three regions was highly significantly increased. When 5HIAA/5HT ratios, as a measure of serotonin turnover, were calculated, imprinted animals showed extremely high values. Plasma nocistatin level was also significantly elevated. The results call attention to the effect of perinatal endorphin imprinting and its long-term consequences (e.g., setting of aggressiveness, pain tolerance).

The Parametric Instability of Alfvén Waves: Effects of Temperature Anisotropy

NASA Astrophysics Data System (ADS)

Tenerani, Anna; Velli, Marco; Hellinger, Petr

2017-12-01

We study the stability of large-amplitude, circularly polarized Alfvén waves in an anisotropic plasma described by the double-adiabatic/CGL closure, and in particular the effect of a background thermal pressure anisotropy on the well-known properties of Alfvén wave parametric decay in magnetohydrodynamics (MHD). Anisotropy allows instability over a much wider range of values of parallel plasma beta (β ∥) when ξ = p 0⊥/p 0∥ > 1. When the pressure anisotropy exceeds a critical value, ξ ≥ ξ* with ξ* ≃ 2.7, there is a new regime in which the parametric instability is no longer quenched at high β ∥, and in the limit β ∥ ≫ 1, the growth rate becomes independent of β ∥. In the opposite case of ξ < ξ*, the instability is strongly suppressed with increasing parallel plasma beta, similarly to the MHD case. We analyze marginal stability conditions for parametric decay in the (ξ, β ∥) parameter space and discuss possible implications for Alfvénic turbulence in the solar wind.

Specific radioimmunoassay of human. beta. -endorphin in unextracted plasma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiedemann, E.; Saito, T.; Linfoot, J.A.

1979-09-01

With an antiserum against human ..beta..-endorphin (..beta..-EP) crossreacting <2% with human ..beta..-lipotropin (..beta..-LPH) by weight we have developed a radioimmunoassay that can detect 1 pg ..beta..-EP in diluted raw plasma. In a.m. fasting plasma of 14 normal subjects ..beta..-EP ranged from <5 to 45 pg/ml. ..beta..-EP was elevated in untreated, but normal in successfully treated Cushing's disease; undetectable in a patient with adrenal adenoma; extremely high in Nelson's syndrome; and elevated in a patient with bronchogenic carcinoma before, but undetectable after tumor resection. In subjects with intact hypothalamic-pituitary-adrenal axis, ..beta..-EP was undectectable after dexamethasone and increased after metyrapone administration andmore » insulin-induced hypoglycemia. ..beta..-EP concentration was considerably lower in serum than in simultaneously collected plasma, but increased in serum left unfrozen for several hours after clot removal. Thus, ..beta..-EP behaves like a hormone responding to the same stimuli as ACTH and ..beta..-LPH and blood appears to contain enzymes both generating and destroying immunoreactive ..beta..-EP.« less

CYP3A induction and inhibition by different antiretroviral regimens reflected by changes in plasma 4beta-hydroxycholesterol levels.

PubMed

Josephson, F; Bertilsson, L; Böttiger, Y; Flamholc, L; Gisslén, M; Ormaasen, V; Sönnerborg, A; Diczfalusy, U

2008-08-01

A member of the major human cytochrome P450 superfamily of hemoproteins, CYP3A4/5, converts cholesterol into 4beta-hydroxycholesterol. We studied plasma 4beta-hydroxycholesterol levels prior to and 4 weeks after initiating antiretroviral therapy that included efavirenz, ritonavir-boosted atazanavir or ritonavir-boosted lopinavir with the aim of exploring the usefulness of plasma 4beta-hydroxycholesterol levels as an endogenous biomarker of CYP3A activity. Efavirenz is an inducer of CYP3A, whereas the ritonavir-boosted regimens are net inhibitors of CYP3A. In patients treated with efavirenz, the median plasma 4beta-hydroxycholesterol level increased by 46 ng/mL (p = 0.004; n = 11). In contrast, patients given ritonavir-boosted atazanavir showed a median decrease in plasma 4beta-hydroxycholesterol of -9.4 ng/mL (p = 0.0003; n = 22), and those given ritonavir-boosted lopinavir showed a median change from baseline of -5.8 ng/mL (p = 0.38; n = 19). There were significant between-group differences in the effects of antiretroviral treatment on plasma 4beta-hydroxycholesterol levels (p < 0.0001). Changes in plasma 4beta-hydroxycholesterol following the initiation of efavirenz- or atazanavir/ritonavir-based antiretroviral therapy reflected the respective net increase and decrease of CYP3A activity of these regimens. The plasma 4beta-hydroxycholesterol level did not indicate a net CYP3A inhibition in the lopinavir/ritonavir arm, possibly because of concomitant enzyme induction.

Interferon-beta1a reduces plasma CD31+ endothelial microparticles (CD31+EMP) in multiple sclerosis.

PubMed

Sheremata, William A; Jy, Wenche; Delgado, Sylvia; Minagar, Alireza; McLarty, Jerry; Ahn, Yeon

2006-09-04

A correlation between plasma CD31+ endothelial microparticles (CD31+EMP) levels and clinical, as well as brain MRI activity, in multiple sclerosis (MS) patients has been previously reported. However, the effect(s) of treatment with interferon-beta1a (IFN-beta1a) on plasma levels of CD31+EMP has not been assessed. In a prospective study, we measured plasma CD31+EMP levels in 30 patients with relapsing-remitting MS. Using flow cytometry, in a blinded study, we measured plasma CD31+EMP in 30 consecutive patients with relapsing-remitting MS (RRMS) prior to and 4, 12, 24 and 52 weeks after initiation of intramuscular therapy with interferon-beta1a (IFN-beta1a), 30 micrograms weekly. At each visit, clinical examination was performed and expanded disability status scale (EDSS) scores were assessed. Plasma levels of CD31+EMP were significantly reduced from 24 through 52 weeks following initiation of treatment with IFN-beta1a. Our data suggest that serial measurement of plasma CD31+EMP levels may be used as a surrogate marker of response to therapy with INF-beta1a. In addition, the decline in plasma levels of CD31+EMP further supports the concept that IFN-beta1a exerts stabilizing effect on the cerebral endothelial cells in pathogenesis of MS.

Consuming High-Carotenoid Fruit and Vegetables Influences Skin Yellowness and Plasma Carotenoids in Young Women: A Single-Blind Randomized Crossover Trial.

PubMed

Pezdirc, Kristine; Hutchesson, Melinda J; Williams, Rebecca L; Rollo, Megan E; Burrows, Tracy L; Wood, Lisa G; Oldmeadow, Christopher; Collins, Clare E

2016-08-01

Consumption of dietary carotenoids from fruits and vegetables (F/V) leads to accumulations in human skin, altering skin yellowness. The influence of the quantity of F/V consumed on skin yellowness and plasma carotenoid concentrations has not been examined previously. To compare the influence of consuming high-carotenoid-containing F/V (HCFV) (176,425 μg beta carotene/wk) vs low-carotenoid F/V (LCFV) (2,073 μg beta carotene/wk) on skin yellowness and plasma carotenoid concentrations, over 4 weeks. A single-blind randomized controlled crossover trial from October 2013 to March 2014. Thirty women were randomized to receive 7 daily servings of HCFV or LCFV for 4 weeks. Following a 2-week washout period they followed the alternate intervention. Skin color (Commission Internationale de l'Eclairage L*a*b* color space, where L* represents skin lightness and positive values of a* and b* represent degrees of redness and yellowness, respectively) was assessed by reflectance spectroscopy in both sun-exposed and nonexposed skin areas. Fasting plasma carotenoids were determined by high-performance liquid chromatography, before and after each intervention period. Linear mixed models were used to determine the HCFV and LCFV response on skin color and plasma carotenoids, adjusting for intervention order, time, and interaction between baseline differences and time. There were no significant differences in mean daily fruit (P=0.42) and vegetable (P=0.17) intakes between HCFV and LCFV groups. Dietary alpha carotene, beta carotene, lutein, and beta cryptoxanthin intakes were significantly different between the two groups (P<0.01). Following HCFV there was a significantly greater increase in skin yellowness (b*) in both sun-exposed (P<0.001) and unexposed areas, (P<0.001), with no change in skin lightness (L*) or redness (a*). Significantly higher plasma alpha carotene (P=0.004), beta carotene (P=0.001), and lutein (P=0.028) concentrations were found following the HCFV intervention. Skin yellowness correlated with alpha carotene and beta carotene. Skin yellowness (b*) and fasting plasma carotenoid concentrations were significantly higher following HCFV than LCFV over 4 weeks. Copyright © 2016 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Anisotropic shock jump conditions: Theory and observations

NASA Technical Reports Server (NTRS)

Chao, J. K.; Zhang, X. X.; Song, P.

1995-01-01

The MHD Rankine-Hugoniot (RH) relations for shock waves in a collisionless plasma with bi-Maxwellian distribution functions are considered. While by introducing the pressure anisotropy parameter xi in the RH relations, the number of unknowns -- B, V, n, p and xi (a total of 9) -- becomes one more than the total number of the conservation equations, it is possible to use the observed quantities on both sides of the shock to study the anisotropy changes across the shock. A simple relation for the anisotropy change across the shock is derived as a function of the ratio of magnetic fields m(= B'/B), the shock normal angle theta(sub Bn) and the plasma beta and beta' (primes are downstream values). Since m and theta(sub Bn) can be determined accurately in observation, the reliability of the anisotropy change deduced is mostly dependent on the accuracy of the measurements beta and beta'. We have applied the results to six low-beta quasi-perpendicular (Q perpendicular) laminar bow shock crossings with temperature anisotropy measured in the magnetosheath. In the six test cases, it is found that the predicted pressure anisotropies agree well with those observed in the magnetosheath.

Physics Basis for the Advanced Tokamak Fusion Power Plant ARIES-AT

DOE Office of Scientific and Technical Information (OSTI.GOV)

S.C. Jardin; C.E. Kessel; T.K. Mau

2003-10-07

The advanced tokamak is considered as the basis for a fusion power plant. The ARIES-AT design has an aspect ratio of A always equal to R/a = 4.0, an elongation and triangularity of kappa = 2.20, delta = 0.90 (evaluated at the separatrix surface), a toroidal beta of beta = 9.1% (normalized to the vacuum toroidal field at the plasma center), which corresponds to a normalized beta of bN * 100 x b/(I(sub)P(MA)/a(m)B(T)) = 5.4. These beta values are chosen to be 10% below the ideal-MHD stability limit. The bootstrap-current fraction is fBS * I(sub)BS/I(sub)P = 0.91. This leads tomore » a design with total plasma current I(sub)P = 12.8 MA, and toroidal field of 11.1 T (at the coil edge) and 5.8 T (at the plasma center). The major and minor radii are 5.2 and 1.3 m, respectively. The effects of H-mode edge gradients and the stability of this configuration to non-ideal modes is analyzed. The current-drive system consists of ICRF/FW for on-axis current drive and a lower-hybrid system for off-axis. Tran sport projections are presented using the drift-wave based GLF23 model. The approach to power and particle exhaust using both plasma core and scrape-off-layer radiation is presented.« less

Insulin sensitivity and beta-cell function in healthy cats: assessment with the use of the hyperglycemic glucose clamp.

PubMed

Slingerland, L I; Robben, J H; van Haeften, T W; Kooistra, H S; Rijnberk, A

2007-05-01

A hyperglycemic clamp (HGC) was developed for use in conscious cats. In 21 healthy, normal glucose tolerant cats glucose disposal rate (M), insulin sensitivity (ISI (HGC)), and beta-cell response (I) at arterial plasma glucose of 9 mmol.l (-1) were measured. The HGC was tolerated well and steady state glucose infusion was achieved. Compared to values reported for humans, M values for the cats were low, which appeared to relate to both a low ISI (HGC) and a low I. HGC measures correlated with fasting plasma glucose and insulin concentrations as well as with their HOMA (homeostasis model assessment) and QUICKI (quantitative insulin sensitivity check index) counterparts. Also, I and ISI (HGC) correlated with their counterparts derived from intravenous glucose tolerance tests. In conclusion, this is the first report of hyperglycemic glucose clamping in cats. The procedure (HGC) allows for measurements of glucose disposal, beta-cell response and insulin sensitivity. Compared to human data, both insulin sensitivity and insulin secretion appeared to be low in cats. This is compatible with the carnivorous nature of this species, for which insulin resistance would be advantageous during periods of restricted food availability.

Effects of two novel tachykinin antagonists, FK224 and FK888, on neurogenic airway plasma exudation, bronchoconstriction and systemic hypotension in guinea-pigs in vivo.

PubMed Central

Hirayama, Y.; Lei, Y. H.; Barnes, P. J.; Rogers, D. F.

1993-01-01

1. We compared the effects of two novel tachykinin receptor antagonists, FK888 (selective at the tachykinin NK1 receptor) and FK224 (dual antagonist at NK1 and NK2 tachykinin receptors) on stimulus-evoked airway plasma exudation, bronchoconstriction and systemic hypotension in guinea-pigs in vivo. Plasma exudation was induced by substance P (SP), synthetic tachykinin receptor agonists, platelet activating factor (PAF), electrical stimulation of the cervical vagus nerves or by inhalation of cigarette smoke. Changes in airway tone and in carotid artery blood pressure (BP) were induced by synthetic tachykinin agonists, PAF and vagal stimulation. 2. Both FK224 and FK888 dose-dependently inhibited SP-induced plasma exudation in the lower trachea and main bronchi (ID50 values respectively of 1.1 and 0.1 mumol kg-1 in lower trachea, and of 0.5 and 0.1 mumol kg-1 in main bronchi) with complete inhibition at both airway levels at 10 mumol kg-1 for FK224 and at 2 mumol kg-1 for FK888. 3. The NK1-selective tachykinin receptor agonist, [Sar9,Met(O2)11]substance P ([Sar]SP), induced plasma exudation, a response which was blocked by both FK888 and FK224. The NK2-selective agonist, [beta-Ala8]neurokinin A-(4-10) ([beta-Ala]NKA), did not induce plasma exudation: neither FK888 nor FK224 affected this lack of response to [beta-Ala]NKA. 4. [beta-Ala]NKA induced bronchoconstriction, a response which was blocked by FK224 but which was completely unaffected by FK888. [Sar]SP induced a small but significant bronchoconstriction which was completely inhibited by both tachykinin antagonists. 5. In animals pretreated with capsaicin to deplete sensory neuropeptides, PAF induced both plasma exudation and bronchoconstriction.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7682142

Occurrence of high-beta superthermal plasma events in the close environment of Jupiter's bow shock as observed by Ulysses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marhavilas, P. K.; Sarris, E. T.; Anagnostopoulos, G. C.

2011-01-04

The ratio of the plasma pressure to the magnetic field pressure (or of their energy densities) which is known as the plasma parameter 'beta'({beta}) has important implications to the propagation of energetic particles and the interaction of the solar wind with planetary magnetospheres. Although in the scientific literature the contribution of the superthermal particles to the plasma pressure is generally assumed negligible, we deduced, by analyzing energetic particles and magnetic field measurements recorded by the Ulysses spacecraft, that in a series of events, the energy density contained in the superthermal tail of the particle distribution is comparable to or evenmore » higher than the energy density of the magnetic field, creating conditions of high-beta plasma. More explicitly, in this paper we analyze Ulysses/HI-SCALE measurements of the energy density ratio (parameter {beta}{sub ep}) of the energetic ions'(20 keV to {approx}5 MeV) to the magnetic field's in order to find occurrences of high-beta ({beta}{sub ep}>1) superthermal plasma conditions in the environment of the Jovian magnetosphere, which is an interesting plasma laboratory and an important source of emissions in our solar system. In particular, we examine high-beta ion events close to Jupiter's bow shock, which are produced by two processes: (a) bow shock ion acceleration and (b) ion leakage from the magnetosphere.« less

The enteroinsular axis and endocrine pancreatic function in chronic alcohol consumers: evidence for early beta-cell hypofunction.

PubMed

Patto, R J; Russo, E K; Borges, D R; Neves, M M

1993-09-01

Chronic alcohol consumers may have, as judged by functional criteria, exocrine as well as endocrine pancreatic dysfunction, the latter represented by a decreased insulin response to an oral glucose load. To investigate whether this decreased insulin response was due to an ethanol-induced beta-cell dysfunction or to an ethanol-induced dysfunction of the enteroinsular axis, we determined glucose, insulin, and C-peptide plasma concentrations following an oral and an intravenous glucose load in 16 healthy volunteer nonalcohol consumers and in 10 chronic alcohol consumers. In each group, total integrated response for glucose did not significantly change whether glucose was given orally or intravenously, indicating isoglycemic glucose loads. The total integrated response values for insulin in the alcoholic group following both glucose loads as well as C-peptide plasma concentrations were significantly lower than in the control group. Moreover, in both groups the insulin TIR values following the oral glucose load were significantly greater than the values obtained following the intravenous glucose load, indicating an incretin effect. These results indicate that the decreased insulin response observed in alcoholics was not caused by a dysfunction of the enteroinsular axis because it also occurred following an intravenous glucose load, but by an ethanol-induced beta-cell dysfunction because C-peptide and insulin were proportionally decreased in this group.

Changes in numbers of large ovarian follicles, plasma luteinizing hormone and estradiol-17beta concentrations and egg production figures in farmed ostriches throughout the year.

PubMed

Bronneberg, R G G; Stegeman, J A; Vernooij, J C M; Dieleman, S J; Decuypere, E; Bruggeman, V; Taverne, M A M

2007-06-01

In this study we described and analysed changes in the numbers of large ovarian follicles (diameter 6.1-9.0 cm) and in the plasma concentrations of luteinizing hormone (LH) and estradiol-17beta (E(2)beta) in relation to individual egg production figures of farmed ostriches (Struthio camelus spp.) throughout one year. Ultrasound scanning and blood sampling for plasma hormone analysis were performed in 9 hens on a monthly basis during the breeding season and in two periods of the non-breeding season. Our data demonstrated that: (1) large follicles were detected and LH concentrations were elevated already 1 month before first ovipositions of the egg production season took place; (2) E(2)beta concentrations increased as soon as the egg production season started; (3) numbers of large follicles, LH and E(2)beta concentrations were elevated during the entire egg production season; and that (4) numbers of large follicles, LH and E(2)beta concentrations decreased simultaneous with or following the last ovipositions of the egg production season. By comparing these parameters during the egg production season with their pre-and post-seasonal values, significant differences were found in the numbers of large follicles and E(2)beta concentrations between the pre-seasonal, seasonal and post-seasonal period; while LH concentrations were significantly different between the seasonal and post-seasonal period. In conclusion, our data demonstrate that changes in numbers of large follicles and in concentrations of LH and E(2)beta closely parallel individual egg production figures and provide some new cues that egg production in ostriches is confined to a marked reproductive season. Moreover, our data provide indications that mechanism, initiating, maintaining and terminating the egg production season in farmed breeding ostriches are quite similar to those already known for other seasonal breeding bird species.

Exercise- and cold-induced changes in plasma beta-endorphin and beta-lipotropin in men and women.

PubMed

Viswanathan, M; Van Dijk, J P; Graham, T E; Bonen, A; George, J C

1987-02-01

The plasma beta-endorphin (beta-EP) and beta-lipotropin (beta-LPH) response of men, eumenorrheic women, and amenorrheic women (n = 6) to 1 h of rest or to a bicycle ergometer test [20 min at 30% maximum O2 uptake (VO2max), 20 min at 60% VO2max, and at 90% VO2max to exhaustion] was studied in both normal (22 degrees C) and cold (5 degrees C) environments. beta-EP and beta-LPH was measured by radioimmunoassay in venous samples collected every 20 min during rest or after each exercise bout. Exhaustive exercise at ambient temperature (Ta) 22 degrees C induced significant increases in plasma beta-EP and beta-LPH in all subjects as did work at 60% VO2max in amenorrheic and eumenorrheic women. During work at Ta 5 degrees C, the relative increase in beta-EP and beta-LPH was suppressed in eumenorrheic women and completely prevented in amenorrheic women. Although significant lowering of beta-EP and beta-LPH was observed in men and eumenorrheic women during rest at 5 degrees C, amenorrheic women maintained precold exposure levels. These findings suggest that plasma beta-EP and beta-LPH may reflect a thermoregulatory response to heat load. There appears to be a sexual dimorphism in exercise- and cold-induced release of beta-EP and beta-LPH and amenorrhea may be accompanied by alterations in these responses.

Magnetic ramp scale at supercritical perpendicular collisionless shocks: Full particle electromagnetic simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Zhongwei; SOA Key Laboratory for Polar Science, Polar Research Institute of China, Shanghai, 200136; Lu, Quanming

2013-09-15

Supercritical perpendicular collisionless shocks are known to exhibit foot, ramp, and overshoot structures. The shock ramp structure is in a smaller scale in contrast to other microstructures (foot and overshoot) within the shock front. One-dimensional full particle simulations of strictly perpendicular shocks over wide ranges of ion beta β{sub i}, Alfvén Mach number M{sub A}, and ion-to-electron mass ratio m{sub i}/m{sub e} are presented to investigate the impact of plasma parameters on the shock ramp scale. Main results are (1) the ramp scale can be as small as several electron inertial length. (2) The simulations suggest that in a regimemore » below the critical ion beta value, the shock front undergoes a periodic self-reformation and the shock ramp scale is time-varying. At higher ion beta values, the shock front self-reformation is smeared. At still higher ion beta value, the motion of reflected ions is quite diffuse so that they can lead to a quasi-steady shock ramp. Throughout the above three conditions, the shock ramp thickness increases with β{sub i}. (3) The increase (decrease) in Mach number and the decrease (increase) in the beta value have almost equivalent impact on the state (i.e., stationary or nonstationary) of the shock ramp. Both of front and ramp thicknesses are increased with M{sub A}.« less

High beta plasma operation in a toroidal plasma producing device

DOEpatents

Clarke, John F.

1978-01-01

A high beta plasma is produced in a plasma producing device of toroidal configuration by ohmic heating and auxiliary heating. The plasma pressure is continuously monitored and used in a control system to program the current in the poloidal field windings. Throughout the heating process, magnetic flux is conserved inside the plasma and the distortion of the flux surfaces drives a current in the plasma. As a consequence, the total current increases and the poloidal field windings are driven with an equal and opposing increasing current. The spatial distribution of the current in the poloidal field windings is determined by the plasma pressure. Plasma equilibrium is maintained thereby, and high temperature, high beta operation results.

Characterization of microalgal carotenoids by mass spectrometry and their bioavailability and antioxidant properties elucidated in rat model.

PubMed

Ranga Rao, A; Raghunath Reddy, R L; Baskaran, V; Sarada, R; Ravishankar, G A

2010-08-11

Of the total carotenoids in respective algal samples, beta-carotene in Spirulina platensis was 69.5%, astaxanthin and its esters in Haematococcus pluvialis was 81.38%, and lutein in Botryococcus braunii was 74.6%. The carotenoids were characterized by mass spectrometry. A time-course study of carotenoids in rats after administration of microalgal biomass showed peak levels in plasma, liver, and eyes at 2, 4, and 6 h, respectively. Beta-carotene accumulation in Spirulina-fed rats was maximum in eye tissues at 6 h. Similarly, levels of astaxanthin and lutein in Haematococcus- and Botryococcus-fed rats were also maximal in eye tissues. Astaxanthin from H. pluvialis showed better bioavailability than beta-carotene and lutein. The antioxidant enzymes, catalase, superoxide dismutase, peroxidase, and TBARS were significantly high in plasma at 2 h and in liver at 4 h, evidently offering protection from free radicals. This study implies that microalgae can be a good source of carotenoids of high bioavailability and nutraceutical value.

Sub-chronic administration of the 11beta-HSD1 inhibitor, carbenoxolone, improves glucose tolerance and insulin sensitivity in mice with diet-induced obesity.

PubMed

Taylor, Ashley; Irwin, Nigel; McKillop, Aine M; Flatt, Peter R; Gault, Victor A

2008-04-01

We have examined the metabolic effects of daily administration of carbenoxolone (CBX), a naturally occurring 11beta-hydroxysteroid dehydrogenase (11beta-HSD1) inhibitor, in mice with high fat diet-induced insulin resistance and obesity. Eight-week-old male Swiss TO mice placed on a synthetic high fat diet received daily intraperitoneal injections of either saline vehicle or CBX over a 16-day period. Daily administration of CBX had no effect on food intake, but significantly lowered body weight (1.1- to 1.2-fold) compared to saline-treated controls. Non-fasting plasma glucose levels were significantly decreased (1.6-fold) by CBX treatment on day 4 and remained lower throughout the treatment period. Circulating plasma corticosterone levels were not significantly altered by CBX treatment. Plasma glucose concentrations of CBX-treated mice were significantly reduced (1.4-fold) following an intraperitoneal glucose load compared with saline controls. Similarly, after 16-day treatment with CBX, exogenous insulin evoked a significantly greater reduction in glucose concentrations (1.4- to 1.8-fold). 11beta-HSD1 gene expression was significantly down-regulated in liver, whereas glucocorticoid receptor gene expression was increased in both liver and adipose tissue following CBX treatment. The reduced body weight and improved metabolic control in mice with high fat diet-induced obesity upon daily CBX administration highlights the potential value of selective 11beta-HSD1 inhibition as a new route for the treatment of type 2 diabetes and obesity.

Simulation of High-Beta Plasma Confinement

NASA Astrophysics Data System (ADS)

Font, Gabriel; Welch, Dale; Mitchell, Robert; McGuire, Thomas

2017-10-01

The Lockheed Martin Compact Fusion Reactor concept utilizes magnetic cusps to confine the plasma. In order to minimize losses through the axial and ring cusps, the plasma is pushed to a high-beta state. Simulations were made of the plasma and magnetic field system in an effort to quantify particle confinement times and plasma behavior characteristics. Computations are carried out with LSP using implicit PIC methods. Simulations of different sub-scale geometries at high-Beta fusion conditions are used to determine particle loss scaling with reactor size, plasma conditions, and gyro radii. ©2017 Lockheed Martin Corporation. All Rights Reserved.

Correlation between plasma steroid hormones and vitellogenin profiles and lunar periodicity in the female golden rabbitfish, Siganus guttatus (Bloch).

PubMed

Rahman, M D; Takemura, A; Takano, K

2000-09-01

Characteristics of the lunar reproductive cycle in the golden rabbitfish, Siganus guttatus, were determined by histological observations of ovarian development, and immunological measurements of plasma steroid hormones, estradiol-17beta (E2), testosterone (T), 17alpha,20beta-dihydroxy-4-pregnen-3-one (DHP) and 17alpha,20beta,21-trihydroxy-4-pregnen-3-one (20beta-S), and vitellogenin (VTG). Ovarian and plasma samples were collected every week according to the lunar phases from May to July. Weekly change of gonadosomatic index (GSI) showed two peaks at the first lunar quarter in June and July. Yolky oocytes were also observed around this time. Histological observations revealed that the vitellogenic oocytes appeared again 1 week after spawning and developed synchronously. These results suggest that this species is a multiple spawner and the oocyte development is in a group-synchronous manner. Plasma steroid hormones (E2, T, DHP and 20beta-S) and VTG levels changed in parallel with changes in GSI. The peak of plasma VTG level occurred prior to spawning. These cyclic changes of plasma steroid hormones and VTG support the hypothesis that lunar periodicity is the major factor in stimulating reproductive activity of S. guttatus.

Relationship between subclinical rejection and genotype, renal messenger RNA, and plasma protein transforming growth factor-beta1 levels.

PubMed

Hueso, Miguel; Navarro, Estanis; Moreso, Francesc; Beltrán-Sastre, Violeta; Ventura, Francesc; Grinyó, Josep M; Serón, Daniel

2006-05-27

Transforming growth factor (TGF)-beta(1) is increased in allograft rejection and its production is associated with single nucleotide polymorphisms (SNPs). The contribution of SNPs at codons 10 and 25 of the TGF-beta(1) gene to renal allograft damage was assessed in 6-month protocol biopsies and their association with TGF-beta(1) production. TGF-beta(1) genotypes were evaluated by polymerase chain reaction (PCR)/restriction fragment length polymorphism. Intragraft TGF-beta(1) messenger RNA (mRNA) was measured by real-time PCR and TGF-beta(1) plasma levels were assessed by enzyme-linked immunosorbent assay. Eighty consecutive patients were included. Allele T at codon 10 (risk ratio, 6.7; P = 0.02) and an episode of acute rejection before protocol biopsy (risk ratio, 6.2; P = 0.01) were independent predictors of subclinical rejection (SCR). TGF-beta(1) plasma levels, but not those of TGF-beta(1) mRNA, were increased in patients with SCR (2.59 ng/mL +/- 0.91 [n = 22] vs. 2.05 ng/mL +/- 0.76 [n = 43]; P = 0.01). There was no association between allele T and TGF-beta(1) plasma or intragraft levels. Allele T at codon 10 of the TGF-beta(1) gene is associated with a higher incidence of SCR.

Electromagnetic effects on dynamics of high-beta filamentary structures

DOE PAGES

Lee, Wonjae; Umansky, Maxim V.; Angus, J. R.; ...

2015-01-12

The impacts of the electromagnetic effects on blob dynamics are considered. Electromagnetic BOUT++ simulations on seeded high-beta blobs demonstrate that inhomogeneity of magnetic curvature or plasma pressure along the filament leads to bending of the blob filaments and the magnetic field lines due to increased propagation time of plasma current (Alfvén time). The bending motion can enhance heat exchange between the plasma facing materials and the inner SOL region. The effects of sheath boundary conditions on the part of the blob away from the boundary are also diminished by the increased Alfvén time. Using linear analysis and the BOUT++ simulation,more » it is found that electromagnetic effects in high temperature and high density plasmas reduce the growth rate of resistive drift wave turbulence when resistivity drops below some certain value. Lastly, in the course of blobs motion in the SOL its temperature is reduced, which leads to enhancement of resistive effects, so the blob can switch from electromagnetic to electrostatic regime, where resistive drift wave turbulence become important.« less

Reduced and high molecular weight barley beta-glucans decrease plasma total and non-HDL-cholesterol in hypercholesterolemic Syrian golden hamsters.

PubMed

Wilson, Thomas A; Nicolosi, Robert J; Delaney, Bryan; Chadwell, Kim; Moolchandani, Vikas; Kotyla, Timothy; Ponduru, Sridevi; Zheng, Guo-Hua; Hess, Richard; Knutson, Nathan; Curry, Leslie; Kolberg, Lore; Goulson, Melanie; Ostergren, Karen

2004-10-01

Consumption of concentrated barley beta-glucan lowers plasma cholesterol because of its soluble dietary fiber nature. The role of molecular weight (MW) in lowering serum cholesterol is not well established. Prior studies showed that enzymatic degradation of beta-glucan eliminates the cholesterol-lowering activity; however, these studies did not evaluate the MW of the beta-glucan. The current study was conducted to evaluate whether barley beta-glucan concentrates, partially hydrolyzed to reduce MW, possess cholesterol-lowering and antiatherogenic activities. The reduced MW fraction was compared with a high MW beta-glucan concentrate from the same barley flour. Concentrated beta-glucan preparations were evaluated in Syrian Golden F(1)B hamsters fed a hypercholesterolemic diet (HCD) with cholesterol, hydrogenated coconut oil, and cellulose. After 2 wk, hamsters were fed HCD or diets that contained high or reduced MW beta-glucan at a concentration of 8 g/100 g at the expense of cellulose. Decreases in plasma total cholesterol (TC) and non-HDL-cholesterol (non-HDL-C) concentrations occurred in the hamsters fed reduced MW and high MW beta-glucan diets. Plasma HDL-C concentrations did not differ. HCD-fed hamsters had higher plasma triglyceride concentrations. Liver TC, free cholesterol, and cholesterol ester concentrations did not differ. Aortic cholesterol ester concentrations were lower in the reduced MW beta-glucan-fed hamsters. Consumption of either high or reduced MW beta-glucan increased concentrations of fecal total neutral sterols and coprostanol, a cholesterol derivative. Fecal excretion of cholesterol was greater than in HCD-fed hamsters only in those fed the reduced MW beta-glucan. Study results demonstrate that the cholesterol-lowering activity of barley beta-glucan may occur at both lower and higher MW.

Effect of a barley-vegetable soup on plasma carotenoids and biomarkers of cardiovascular disease.

PubMed

Bacchetti, Tiziana; Tullii, Domenico; Masciangelo, Simona; Gesuita, Rosaria; Skrami, Edlira; Brugè, Francesca; Silvestri, Sonia; Orlando, Patrick; Tiano, Luca; Ferretti, Gianna

2015-07-01

Functional foods that provide benefits beyond their traditional nutritional value have attracted much interest. Aim of the study was to evaluate the nutritional and the functional properties of a frozen ready-to-eat soup containing barley and pigmented vegetables. Both glycaemic index and the glyceamic load of ready-to-eat soup were evaluated in vivo. Moreover the bioavailability of carotenoids (lutein and beta-carotene) and the effect on lipid profile and lipid peroxidation were studied in 38 volunteers whose diet was supplemented for two weeks with a daily portion (250 g) of the ready-to-eat soup. Plasma levels of carotenoids (lutein and beta-carotene) and plasma total antioxidant capacity significantly increased after 2 weeks of treatment. Furthermore, we observed a decrease in the levels of lipids (total cholesterol and low density lipoprotein-cholesterol) and of markers of lipid peroxidation (oxidized low density lipoprotein and lipid hydroperoxides) in plasma of all subjects. The glyceamic index of the product was 36, therefore it could be considered a low glyceamic index food. An accurate selection of vegetable foods results in a palatable and healthy product that provides benefits on plasma lipids and lipid peroxidation (Protocol number 211525).

Effect of a barley-vegetable soup on plasma carotenoids and biomarkers of cardiovascular disease

PubMed Central

Bacchetti, Tiziana; Tullii, Domenico; Masciangelo, Simona; Gesuita, Rosaria; Skrami, Edlira; Brugè, Francesca; Silvestri, Sonia; Orlando, Patrick; Tiano, Luca; Ferretti, Gianna

2015-01-01

Functional foods that provide benefits beyond their traditional nutritional value have attracted much interest. Aim of the study was to evaluate the nutritional and the functional properties of a frozen ready-to-eat soup containing barley and pigmented vegetables. Both glycaemic index and the glyceamic load of ready-to-eat soup were evaluated in vivo. Moreover the bioavailability of carotenoids (lutein and beta-carotene) and the effect on lipid profile and lipid peroxidation were studied in 38 volunteers whose diet was supplemented for two weeks with a daily portion (250 g) of the ready-to-eat soup. Plasma levels of carotenoids (lutein and beta-carotene) and plasma total antioxidant capacity significantly increased after 2 weeks of treatment. Furthermore, we observed a decrease in the levels of lipids (total cholesterol and low density lipoprotein-cholesterol) and of markers of lipid peroxidation (oxidized low density lipoprotein and lipid hydroperoxides) in plasma of all subjects. The glyceamic index of the product was 36, therefore it could be considered a low glyceamic index food. An accurate selection of vegetable foods results in a palatable and healthy product that provides benefits on plasma lipids and lipid peroxidation (Protocol number 211525). PMID:26236103

Global modelling of plasma-wall interaction in reversed field pinches

NASA Astrophysics Data System (ADS)

Bagatin, M.; Costa, S.; Ortolani, S.

1989-04-01

The impurity production and deuterium recycling mechanisms in ETA—BETA II and RFX are firstly discussed by means of a simple model applicable to a stationary plasma interacting with the wall. This gives the time constant and the saturation values of the impurity concentration as a function of the boundary temperature and density. If the latter is sufficiently high, the impurity buildup in the main plasma becomes to some extent stabilized by the shielding effect of the edge. A self-consistent global model of the time evolution of an RFP plasma interacting with the wall is then described. The bulk and edge parameters are derived by solving the energy and particle balance equations incorporating some of the basic plasma-surface processes, such as sputtering, backscattering and desorption. The application of the model to ETA-BETA II confirms the impurity concentrations of the light and metal impurities as well as the time evolution of the average electron density found experimentally under different conditions. The model is then applied to RFX, a larger RFP experiment under construction, whose wall will be protected by a full graphite armour. The time evolution of the discharge shows that carbon sputtering could increase Zeff to ~ 4, but without affecting significantly the plasma performance.

Which routine test for kidney function?

PubMed Central

Parkin, A; Smith, H C; Brocklebank, J T

1989-01-01

Eighty measurements of plasma creatinine concentration, height:creatinine ratio, and plasma beta 2 microglobulin concentration were made on 72 children (age 4 months-18.5 years) with known renal disease. Results were compared with simultaneous measurements of glomerular filtration rate using plasma clearance of 51Cr edetic acid to assess the performance of each test as an initial screening procedure of renal insufficiency. Height:creatinine index less than 2.1 was found to have a higher sensitivity and predictive value of a normal result than the other tests and is therefore the preferred test for a screening procedure. PMID:2510609

Stability analysis of the high poloidal bet scenario on DIII-Dtowards operation athigher plasma current

NASA Astrophysics Data System (ADS)

Guo, W. F.; Gong, X. Z.; Huang, J.; Ren, Q. L.; Qian, J. P.; Ding, S. Y.; Pan, C. K.; Li, G. Q.; Xia, T. Y.; Garofalo, A. M.; Lao, L.; Hyatt, A.; Ferron, J.; Meneghini, O.; Liu, Y. Q.; McClenaghan, J.; Holcomb, C. T.

2017-10-01

The high poloidal beta scenario with plasma current IP 600 kA and large-radius internal transport barrier (ITB) on DIII-D is subject to n =1 MHD kink modes when the current profile becomes very broad at internal inductance values li 0.5-0.6. It is desirable to extend this scenario to higer plasma current ( 1 MA) for highernormalized fusionperformance. However, higher current at constant normalized beta, ?N 3, would reducethe poloidal bet, ?P, below the threshold for ITB sustainment, observed at ?P 1.9. Thus, to avoid loss of the IT, ?N?? must be increased together with IP while avoiding the kink instability. MHD analysis is presented that explains possible paths to high ?N stability limit for the kink mode in tis scenario. Work supported by National Magnetic Confinement Fusion Program of Chin under 2015GB110001 and 2015GB102000 - National Natural Science Foundation of China under Grant No. 1147521 and by US DOE under DE-FC02-04ER54698.

Substance P-induced trafficking of beta-arrestins. The role of beta-arrestins in endocytosis of the neurokinin-1 receptor.

PubMed

McConalogue, K; Déry, O; Lovett, M; Wong, H; Walsh, J H; Grady, E F; Bunnett, N W

1999-06-04

Agonist-induced redistribution of G-protein-coupled receptors (GPCRs) and beta-arrestins determines the subsequent cellular responsiveness to agonists and is important for signal transduction. We examined substance P (SP)-induced trafficking of beta-arrestin1 and the neurokinin-1 receptor (NK1R) in KNRK cells in real time using green fluorescent protein. Green fluorescent protein did not alter function or localization of the NK1R or beta-arrestin1. SP induced (a) striking and rapid (<1 min) translocation of beta-arrestin1 from the cytosol to the plasma membrane, which preceded NK1R endocytosis; (b) redistribution of the NK1R and beta-arrestin1 into the same endosomes containing SP and the transferrin receptor (2-10 min); (c) prolonged colocalization of the NK1R and beta-arrestin1 in endosomes (>60 min); (d) gradual resumption of the steady state distribution of the NK1R at the plasma membrane and beta-arrestin1 in the cytosol (4-6 h). SP stimulated a similar redistribution of immunoreactive beta-arrestin1 and beta-arrestin2. In contrast, SP did not affect Galphaq/11 distribution, which remained at the plasma membrane. Expression of the dominant negative beta-arrestin319-418 inhibited SP-induced endocytosis of the NK1R. Thus, SP induces rapid translocation of beta-arrestins to the plasma membrane, where they participate in NK1R endocytosis. beta-Arrestins colocalize with the NK1R in endosomes until the NK1R recycles and beta-arrestins return to the cytosol.

Beta-endorphin and islet hormone release in type-2 diabetes mellitus the effects of normoglycemia, enkephalin, naloxone and somatostatin.

PubMed

Giugliano, D; Cozzolino, D; Salvatore, T; Ceriello, A; Giunta, R; Torella, R; D'Onofrio, F

1987-01-01

The present study was aimed at characterizing the effects of beta-endorphin on plasma glucose, insulin and glucagon plasma levels in subjects with type-2 diabetes mellitus. Infusion of 0.5 mg/h human beta-endorphin produced significant and simultaneous increments in both insulin and glucagon concentrations and decreased plasma glucose levels (-18 +/- 4 mg/dl, 60 min level, p less than 0.01). When the same diabetics were rendered euglycemic by an insulin infusion (1 mU/kg/min), beta-endorphin did not produce the expected decrease in plasma glucose concentrations nor raise plasma insulin levels; only the response of glucagon was preserved. Normal subjects were rendered hyperglycemic by an intravenous glucose infusion to match the plasma glucose levels of diabetic subjects. In this condition, beta-endorphin produced a significant increase of insulin concentrations, whereas glucagon remained suppressed. The intravenous administration of the long-acting met-enkephalin analogue DAMME (0.25 mg) blunted the hormonal responses to the subsequent beta-endorphin infusion in diabetic patients, although the inhibition was short-lived (30-40 min). Naloxone (5 mg), an opiate antagonist, did not produce any significant change in the insulin and glucagon responses to beta-endorphin, while somatostatin (0.25 mg/h) completely abolished the hormonal responses to the opioid.(ABSTRACT TRUNCATED AT 250 WORDS)

Canine serum protein patterns using high-resolution electrophoresis (HRE).

PubMed

Abate, O; Zanatta, R; Malisano, T; Dotta, U

2000-03-01

Serum protein values were determined in 26 healthy dogs using agarose gel electrophoresis (SPE), splitting the electrophoretic separation into six regions: albumin, alpha(1), alpha(2), beta(1), beta(2)and gamma globulins. High-resolution electrophoresis (HRE) was used to separate single proteins. Serum proteins from dogs (26 healthy and 20 affected by various diseases) were then characterized by electrophoretic immunofixation (IFE) and Sudan black staining on HRE film. Haemoglobin and normal canine plasma and serum were used to identify haptoglobin and fibrinogen, respectively. In the standard pattern, determined by HRE, the following proteins were identified: albumin, alpha(1)-lipoprotein (alpha(1)-region), haptoglobin and alpha(2)-macroglobulin (alpha(2)-region), beta -lipoprotein and C3 (beta(1)-region), transferrin and IgM (beta(2)-region), IgG (mostly in gamma -region and partly in beta(2)-region). The HRE pattern shown by healthy dogs could be compared with those of dogs affected by various diseases to obtain clinical information. Copyright 2000 Harcourt Publishers Ltd.

Achieving a long-lived high-beta plasma state by energetic beam injection

NASA Astrophysics Data System (ADS)

Guo, H. Y.; Binderbauer, M. W.; Tajima, T.; Milroy, R. D.; Steinhauer, L. C.; Yang, X.; Garate, E. G.; Gota, H.; Korepanov, S.; Necas, A.; Roche, T.; Smirnov, A.; Trask, E.

2015-04-01

Developing a stable plasma state with high-beta (ratio of plasma to magnetic pressures) is of critical importance for an economic magnetic fusion reactor. At the forefront of this endeavour is the field-reversed configuration. Here we demonstrate the kinetic stabilizing effect of fast ions on a disruptive magneto-hydrodynamic instability, known as a tilt mode, which poses a central obstacle to further field-reversed configuration development, by energetic beam injection. This technique, combined with the synergistic effect of active plasma boundary control, enables a fully stable ultra-high-beta (approaching 100%) plasma with a long lifetime.

First demonstration of cerebrospinal fluid and plasma A beta lowering with oral administration of a beta-site amyloid precursor protein-cleaving enzyme 1 inhibitor in nonhuman primates.

PubMed

Sankaranarayanan, Sethu; Holahan, Marie A; Colussi, Dennis; Crouthamel, Ming-Chih; Devanarayan, Viswanath; Ellis, Joan; Espeseth, Amy; Gates, Adam T; Graham, Samuel L; Gregro, Allison R; Hazuda, Daria; Hochman, Jerome H; Holloway, Katharine; Jin, Lixia; Kahana, Jason; Lai, Ming-tain; Lineberger, Janet; McGaughey, Georgia; Moore, Keith P; Nantermet, Philippe; Pietrak, Beth; Price, Eric A; Rajapakse, Hemaka; Stauffer, Shaun; Steinbeiser, Melissa A; Seabrook, Guy; Selnick, Harold G; Shi, Xiao-Ping; Stanton, Matthew G; Swestock, John; Tugusheva, Katherine; Tyler, Keala X; Vacca, Joseph P; Wong, Jacky; Wu, Guoxin; Xu, Min; Cook, Jacquelynn J; Simon, Adam J

2009-01-01

beta-Site amyloid precursor protein (APP)-cleaving enzyme (BACE) 1 cleavage of amyloid precursor protein is an essential step in the generation of the potentially neurotoxic and amyloidogenic A beta 42 peptides in Alzheimer's disease. Although previous mouse studies have shown brain A beta lowering after BACE1 inhibition, extension of such studies to nonhuman primates or man was precluded by poor potency, brain penetration, and pharmacokinetics of available inhibitors. In this study, a novel tertiary carbinamine BACE1 inhibitor, tertiary carbinamine (TC)-1, was assessed in a unique cisterna magna ported rhesus monkey model, where the temporal dynamics of A beta in cerebrospinal fluid (CSF) and plasma could be evaluated. TC-1, a potent inhibitor (IC(50) approximately 0.4 nM), has excellent passive membrane permeability, low susceptibility to P-glycoprotein transport, and lowered brain A beta levels in a mouse model. Intravenous infusion of TC-1 led to a significant but transient lowering of CSF and plasma A beta levels in conscious rhesus monkeys because it underwent CYP3A4-mediated metabolism. Oral codosing of TC-1 with ritonavir, a potent CYP3A4 inhibitor, twice daily over 3.5 days in rhesus monkeys led to sustained plasma TC-1 exposure and a significant and sustained reduction in CSF sAPP beta, A beta 40, A beta 42, and plasma A beta 40 levels. CSF A beta 42 lowering showed an EC(50) of approximately 20 nM with respect to the CSF [TC-1] levels, demonstrating excellent concordance with its potency in a cell-based assay. These results demonstrate the first in vivo proof of concept of CSF A beta lowering after oral administration of a BACE1 inhibitor in a nonhuman primate.

Maternal and cord plasma concentrations of beta-lipotrophin, beta-endorphin and gamma-lipotrophin at delivery; effect of analgesia.

PubMed

Browning, A J; Butt, W R; Lynch, S S; Shakespear, R A; Crawford, J S

1983-12-01

Maternal venous plasma concentrations of beta-LPH, beta-EP and gamma-LPH were compared in (i) patients undergoing vaginal delivery, 11 with an epidural block and 13 with pethidine and nitrous oxide or no analgesics; (ii) patients delivered by caesarean section, 7 under epidural block and 8 under general anaesthesia. Patients delivered by either method under epidural block had significantly lower levels of all three peptides than those receiving no epidural. There were significant negative correlations between umbilical vein beta-LPH, beta-EP and gamma-LPH concentrations and umbilical artery pH and positive correlations between beta-LPH and beta-EP but not gamma-LPH and cord PCO2 in 29 patients. There was no relation between cord levels of any of the three peptides and the method of analgesia or the route of delivery. Although concentrations of all three peptides were closely correlated to one another in either maternal or cord plasma, there was no relationship between maternal and fetal levels.

Studies on the bioavailability of the provitamin A carotenoid, beta-carotene, using human exfoliated colonic epithelial cells.

PubMed

Gireesh, T; Nair, P P; Sudhakaran, P R

2004-08-01

The possibility of using exfoliated colonic epithelial cells for assessing the bioavailability of beta-carotene was examined. Analysis of exfoliated colonic epithelial cells showed the presence of beta-carotene and vitamin A. The beta-carotene content was significantly lower in cells from stool samples of subjects on a beta-carotene-poor diet than those receiving a single dose of a beta-carotene supplement. Colonic epithelial cells isolated from stool samples collected daily during a wash-out period while the subjects were on a beta-carotene-poor diet showed a steady decrease in beta-carotene content, reaching the lowest value on day 7. Kinetic analysis showed that a single dose of a beta-carotene supplement in the form of spirulina (Spirulina platensis) or agathi (Sesbania grandiflora) after the wash-out period caused an increase in the beta-carotene content after a lag period of 5-7 d, but the vitamin A levels during these periods were not significantly affected. Analysis of plasma beta-carotene concentration also showed similar changes, which correlated with those of exfoliated colonic cells. A relationship between the beta-carotene content of the diet and that of the colonic epithelial cells suggests that analysis of the beta-carotene content in exfoliated human colonic epithelial cells is a useful non-invasive method to assess the bioavailability of provitamin A beta-carotene.

[Beta-endorphin and obesity. Possible pathogenetic implications].

PubMed

Giugliano, D; Saccomanno, F; Quatraro, A; Ceriello, A; Torella, R

1990-01-01

Several experimental data have documented the ability of both opiates and opioid peptides to stimulate food intake. On the other hand, the plasma beta-endorphin levels found in obese patients are higher than those observed in normal-weight controls, which may have pathogenetic implications. We have investigated the responses of plasma glucose, insulin, C-peptide and glucagon to an infusion of human beta-endorphin in formerly obese subjects who had obtained by dieting the normalization of body weight and in lean controls. The data show that: a) the increased plasma beta-endorphin concentrations found in human obesity are not corrected by normalization of body weight; b) formerly obese subjects behave as obese subjects in their metabolic and hormonal responses to beta-endorphin.

Investigating the ion-scale spectral break of solar wind turbulence from low to high plasma beta with high-resolution hybrid simulations

NASA Astrophysics Data System (ADS)

Franci, Luca; Landi, Simone; Matteini, Lorenzo; Verdini, Andrea; Hellinger, Petr

2016-04-01

We investigate the properties of the ion-scale spectral break of solar wind turbulence by means of two-dimensional, large-scale, high-resolution hybrid particle-in-cell simulations. We impose an initial ambient magnetic field perpendicular to the simulation box, and we add a spectrum of in-plane large- scale magnetic and kinetic fluctuations, with energy equipartition and vanishing correlation. We perform a set of ten simulations with different values of the ion plasma beta, β_i. In all cases, we observe the power spectrum of the total magnetic fluctuations following a power law with a spectral index of -5/3 in the inertial range, with a smooth break around ion scales and a steeper power law in the sub-ion range. This spectral break always occurs at spatial scales of the order of the proton gyroradius, ρ_i, and the proton inertial length, di = ρi / √{β_i}. When the plasma beta is of the order of 1, the two scales are very close to each other and determining which is directly related to the steepening of the spectra it's not straightforward at all. In order to overcome this limitation, we extended the range of values of βi over three orders of magnitude, from 0.01 to 10, so that the two ion scales were well separated. This let us observe that the break always seems to occur at the larger of the two scales, i.e., at di for βi 1. The effect of βi on the spectra of the parallel and perpendicular magnetic components separately and of the density fluctuations is also investigated. We compare all our numerical results with solar wind observations and suggest possible explanations for our findings.

Kinetic effects on Alfven wave nonlinearity. II - The modified nonlinear wave equation

NASA Technical Reports Server (NTRS)

Spangler, Steven R.

1990-01-01

A previously developed Vlasov theory is used here to study the role of resonant particle and other kinetic effects on Alfven wave nonlinearity. A hybrid fluid-Vlasov equation approach is used to obtain a modified version of the derivative nonlinear Schroedinger equation. The differences between a scalar model for the plasma pressure and a tensor model are discussed. The susceptibilty of the modified nonlinear wave equation to modulational instability is studied. The modulational instability normally associated with the derivative nonlinear Schroedinger equation will, under most circumstances, be restricted to left circularly polarized waves. The nonlocal term in the modified nonlinear wave equation engenders a new modulational instability that is independent of beta and the sense of circular polarization. This new instability may explain the occurrence of wave packet steepening for all values of the plasma beta in the vicinity of the earth's bow shock.

Dissociative Attachment Reactions of Electrons with Gas Phase Superacids

NASA Astrophysics Data System (ADS)

Liu, Xifan

Using the flowing afterglow Langmuir probe (FALP) technique, dissociative attachment coefficients beta for reactions of electrons with gas phase superacids HCo(PF_3)_4, HRh(PF _3)_4 and carbonyl hydride complexes HMn(CO)_5, HRe(CO) _5 have been determined under thermal conditions over the approximate temperature range 300~ 550 K. The superacids react relatively slowly (< 1/20 of beta_{rm max}) with free electrons in a thermal plasma, and the values of beta obtained this far do not show a correlation between acidity and beta. The pioneer researchers in this field had speculated that any superacid would be a rapid attacher of electrons; we found that this speculation is not true in general. The product distribution of electron attachment reaction to HCo(PF_3)_4 was found to be independent of temperature even though the beta (HCo(PF_3)_4 ) increases with temperature. This leads us to propose that the electron attachment process occurs well before the excited complex dissociates. In addition, the activation energy of HCo(PF_3)_4 for electron attachment has been derived from the Arrhenius plots. The carbonyl hydride complexes, HMn(CO) _5 and HRe(CO)_5, react relatively rapidly (>1/4 of beta_{rm max}) with free electrons in thermal plasma. This indicates that these reactions cannot be significantly endothermic. Observation of rapid attachment for these non-superacids shows that the Mn-CO and Re-CO bonds are weaker than the Mn-H and Re-H bonds, respectively. Comparisons between the carbonyl and trifluorophosphine cases implies that fast electron capture is related more to the CO ligand than to the transition -metal species.

Edelman's equation is valid in acute hyponatremia in a porcine model: plasma sodium concentration is determined by external balances of water and cations.

PubMed

Overgaard-Steensen, Christian; Larsson, Anders; Bluhme, Henrik; Tønnesen, Else; Frøkiaer, Jørgen; Ring, Troels

2010-01-01

Acute hyponatremia is a serious condition, which poses major challenges. Of particular importance is what determines plasma sodium concentration ([Na(+)]). Edelman introduced an explicit model to describe plasma [Na(+)] in a population as [Na(+)] = alpha.(exchangeable Na(+) + exchangeable K(+))/(total body water) - beta. Evidence for the clinical utility of the model in the individual and in acute hyponatremia is sparse. We, therefore, investigated how the measured plasma [Na(+)] could be predicted in a porcine model of hyponatremia. Plasma [Na(+)] was estimated from in vivo-determined balances of water, Na(+), and K(+), according to Edelman's equation. Acute hyponatremia was induced with desmopressin acetate and infusion of a 2.5% glucose solution in anesthetized pigs. During 480 min, plasma [Na(+)] and osmolality were reduced from 136 (SD 2) to 120 mmol/l (SD 3) and from 284 (SD 4) to 252 mosmol/kgH(2)O (SD 5), respectively. The following interpretations were made. First, Edelman's model, which, besides dilution, takes into account Na(+) and K(+), fits plasma [Na(+)] significantly better than dilution alone. Second, a common value of alpha = 1.33 (SD 0.08) and beta = -13.04 mmol/l (SD 7.68) for all pigs explains well the plasma [Na(+)] in the individual animal. Third, measured exchangeable Na(+) and calculated exchangeable Na(+) + K(+) per weight in the pigs are close to Edelman's findings in humans, whereby the methods are cross-validated. In conclusion, plasma [Na(+)] can be explained in the individual animal by external balances, according to Edelman's construct in acute hyponatremia.

Effects of leuprolide acetate on selected blood and fecal sex hormones in Hispaniolan Amazon parrots (Amazona ventrais).

PubMed

Klaphake, Eric; Fecteau, Kellie; DeWit, Martine; Greenacre, Cheryl; Grizzle, Judith; Jones, Michael; Zagaya, Nancy; Abney, L Kim; Oliver, Jack

2009-12-01

The luteinizing hormone-releasing hormone agonist leuprolide acetate is used commonly to anage reproductive problems in pet birds. To determine the effect of leuprolide acetate on plas a and fecal hormone levels in a psittacine species, a single 800 microg/kg dose of the 30-day depot form of leuprolide acetate was administered IM in 11 healthy, nonbreeding adult Hispaniolan Amazon parrots (Amazona ventralis), and plasma and fecal hormone levels were measured before and after leuprolide administration. At pooled baseline to 21 days postleuprolide acetate administration, sample collection day was significantly associated with plasma 17beta-estradiol and androstenedione levels and fecal 17beta-estradiol levels (evaluated in females only). Both plasma androstenedione and plasma 17beta-estradiol levels decreased significantly from baseline to a nadir at 7 days postleuprolide acetate administration but did not differ significantly 14 days later from that nadir or from pooled baseline samples, suggesting that the effect of leuprolide on hormone levels remained about 2 weeks. Fecal 17beta-estradiol levels increased significantly from the nadir at 7 days postleuprolide to 21 days postleuprolide administration, with trends of the level at 21 days postleuprolide being higher than the pooled baseline level and of decreasing levels from pooled baseline to 7 days postleuprolide administration. Plasma luteinizing hormone and fecal testosterone levels did not change significantly from baseline levels after leuprolide administration over the 2-day period. No significant correlations were found between plasma hormone and fecal hormone levels. These results suggest that measurement of plasma androstenedione, plasma 17beta-estradiol, and fecal 17beta-estradiol levels might be useful in assessing the effects of 30-day depot leuprolide acetate in Hispaniolan Amazon parrots.

Vesicle-associated membrane protein 2 mediates trafficking of {alpha}5{beta}1 integrin to the plasma membrane

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hasan, Nazarul; Hu, Chuan, E-mail: chuan.hu@louisville.edu

2010-01-01

Integrins are major receptors for cell adhesion to the extracellular matrix (ECM). As transmembrane proteins, the levels of integrins at the plasma membrane or the cell surface are ultimately determined by the balance between two vesicle trafficking events: endocytosis of integrins at the plasma membrane and exocytosis of the vesicles that transport integrins. Here, we report that vesicle-associated membrane protein 2 (VAMP2), a SNARE protein that mediates vesicle fusion with the plasma membrane, is involved in the trafficking of {alpha}5{beta}1 integrin. VAMP2 was present on vesicles containing endocytosed {beta}1 integrin. Small interfering RNA (siRNA) silencing of VAMP2 markedly reduced cellmore » surface {alpha}5{beta}1 and inhibited cell adhesion and chemotactic migration to fibronectin, the ECM ligand of {alpha}5{beta}1, without altering cell surface expression of {alpha}2{beta}1 integrin or {alpha}3{beta}1 integrin. By contrast, silencing of VAMP8, another SNARE protein, had no effect on cell surface expression of the integrins or cell adhesion to fibronectin. In addition, VAMP2-mediated trafficking is involved in cell adhesion to collagen but not to laminin. Consistent with disruption of integrin functions in cell proliferation and survival, VAMP2 silencing diminished proliferation and triggered apoptosis. Collectively, these data indicate that VAMP2 mediates the trafficking of {alpha}5{beta}1 integrin to the plasma membrane and VAMP2-dependent integrin trafficking is critical in cell adhesion, migration and survival.« less

Imaging of turbulent structures and tomographic reconstruction of TORPEX plasma emissivity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iraji, D.; Furno, I.; Fasoli, A.

In the TORPEX [A. Fasoli et al., Phys. Plasmas 13, 055902 (2006)], a simple magnetized plasma device, low frequency electrostatic fluctuations associated with interchange waves, are routinely measured by means of extensive sets of Langmuir probes. To complement the electrostatic probe measurements of plasma turbulence and study of plasma structures smaller than the spatial resolution of probes array, a nonperturbative direct imaging system has been developed on TORPEX, including a fast framing Photron-APX-RS camera and an image intensifier unit. From the line-integrated camera images, we compute the poloidal emissivity profile of the plasma by applying a tomographic reconstruction technique usingmore » a pixel method and solving an overdetermined set of equations by singular value decomposition. This allows comparing statistical, spectral, and spatial properties of visible light radiation with electrostatic fluctuations. The shape and position of the time-averaged reconstructed plasma emissivity are observed to be similar to those of the ion saturation current profile. In the core plasma, excluding the electron cyclotron and upper hybrid resonant layers, the mean value of the plasma emissivity is observed to vary with (T{sub e}){sup {alpha}}(n{sub e}){sup {beta}}, in which {alpha}=0.25-0.7 and {beta}=0.8-1.4, in agreement with collisional radiative model. The tomographic reconstruction is applied to the fast camera movie acquired with 50 kframes/s rate and 2 {mu}s of exposure time to obtain the temporal evolutions of the emissivity fluctuations. Conditional average sampling is also applied to visualize and measure sizes of structures associated with the interchange mode. The {omega}-time and the two-dimensional k-space Fourier analysis of the reconstructed emissivity fluctuations show the same interchange mode that is detected in the {omega} and k spectra of the ion saturation current fluctuations measured by probes. Small scale turbulent plasma structures can be detected and tracked in the reconstructed emissivity movies with the spatial resolution down to 2 cm, well beyond the spatial resolution of the probe array.« less

Energy-confinement scaling for high-beta plasmas in the W7-AS stellarator.

PubMed

Preuss, R; Dinklage, A; Weller, A

2007-12-14

High-beta energy-confinement data are subjected to comparisons of scaling invariant, first-principles physical models. The models differ in the inclusion of basic equations indicating the nature of transport. The result for high-beta data of the W7-AS stellarator is that global transport is described best with a collisional high-beta model, which is different from previous outcomes for low-beta data. Model predictive calculations indicate the validation of energy-confinement prediction with respect to plasma beta and collisionality nu*. The finding of different transport behaviors in distinct beta regimes is important for the development of fusion energy based on magnetic confinement and for the assessment of different confinement concepts.

The effects of magnetic B(y) component on geomagnetic tail equilibria

NASA Technical Reports Server (NTRS)

Hilmer, Robert V.; Voigt, Gerd-Hannes

1987-01-01

A two-dimensional linear magnetohydrostatic model of the magnetotail is developed here in order to investigate the effects of a significant B(y) component on the configuration of magnetotail equilibria. It is concluded that the enhanced B(y) values must be an essential part of the quiet magnetotail and do not result from a simple intrusion of the IMF. The B(y) field consists of a constant background component plus a nonuniform field existing only in the plasma sheet, where it is dependent on the plasma paramater beta and the strength of the magnetic B(z) component. B(y) is strongest at the neutral sheet and decreases monotonically in the + or - z direction, reaching a constant tail lobe value at the plasma sheet boundaries. The presence of a significant positive B(y) component produces currents, including field-aligned currents, that flow through the equatorial plane and toward and away from earth in the northern and southern halves of the plasma sheet, respectively.

MHD Studies of Advanced Tokamak Equilibria

NASA Astrophysics Data System (ADS)

Strumberger, E.

2005-10-01

Advanced tokamak scenarios are often characterized by an extremely reversed profile of the safety factor, q, and a fast toroidal rotation. ASDEX Upgrade type equilibria with toroidal flow are computed up to a toroidal Mach number of Mta= 0.5, and compared with the static solution. Using these equilibria, the stabilizing effect of differential toroidal rotation on double tearing modes (DTMs) is investigated. These studies show that the computation of equilibria with flow is necessary for toroidally rotating plasma with Mta>=0.2. The use of ρtor instead of ρpol as radial coordinate enables us also to investigate the stability of equilibria with current holes. For numerical reasons, the rotational transform, = 1/q, has to be unequal zero in the CASTOR$FLOW code, but values of a>=0.001 (qa<=1000) can be easily handled. Stability studies of DTMs in the presence of a current hole are presented. Tokamak equilibria are only approximately axisymmetric. The finite number of toroidal field coils destroys the perfect axisymmetry of the device, and the coils produce a short wavelength ripple in the magnetic field strength. This toroidal field ripple plays a crucial role for the loss of high energy particles. Therefore, three-dimensional tokamak equilibria with and without current holes are computed for various plasma beta values. In addition the influence of the plasma beta on the toroidal field ripple is investigated.

The Arg389Gly beta1-adrenoceptor polymorphism does not affect cardiac effects of exercise after parasympathetic inhibition by atropine.

PubMed

Leineweber, Kirsten; Bruck, Heike; Temme, Thomas; Heusch, Gerd; Philipp, Thomas; Brodde, Otto-Erich

2006-01-01

In vitro, Arg389Gly beta1-adrenoceptor (AR) polymorphism exhibits decreased beta-AR signalling. In vivo, beta1-AR-mediated cardiac effects of exercise showed no genotype-dependent differences in Arg389 vs. Gly389 beta1-AR subjects. We studied in 16 male subjects homozygous Arg389 or Gly389 beta1-AR, whether blockade of parasympathetic activity might unmask genotype-dependence of exercise effects. Subjects were infused with atropine (10 microg/kg i.v. loading dose followed by continuous i.v. infusion of 0.15 microg/kg/min throughout exercise-time); 20 min after start of atropine bicycle-exercise in supine position (25, 50, 75 and 100 W for 5 min each) was performed and heart rate, contractility, blood pressure, plasma noradrenaline and plasma-renin activity were assessed. Exercise-evoked increases in all but one parameters were not different between Arg389 and Gly389 beta1-AR subjects; only plasma noradrenaline increased slightly more in Gly389 vs. Arg389 beta1-AR subjects. It appears to be unlikely that lack of Arg389Gly beta1-AR genotype-dependence of exercise-effects can be explained by influences of parasympathetic activity.

On build-up of magnetic energy in the solar atmosphere

NASA Technical Reports Server (NTRS)

Nakagawa, Y.; Steinolfson, R. S.; Wu, S. T.

1976-01-01

The dynamic response of the solar atmosphere is examined with the use of self-consistent numerical solutions to the complete set of nonlinear two-dimensional hydromagnetic equations. Of particular interest are the magnetic-energy buildup and the velocity field established by emerging flux at the base of an existing magnetic loop structure in a stationary atmosphere. For a plasma with a relatively low beta (0.03), the magnetic-energy buildup is approximately twice that of the kinetic energy, while the buildup in magnetic energy first exceeds but is eventually overtaken by the kinetic energy for a plasma with an intermediate beta (3). The increased magnetic flux causes the plasma to flow upward near the loop center and downward near the loop edges for the low-beta plasma. The plasma eventually flows downward throughout the lower portion of the loop carrying the magnetic field with it for the intermediate beta plasma. It is hypothesized that this latter case, and possibly the other case as well, may provide a reasonable simulation of the disappearance of prominences by flowing down into the chromosphere (a form of disparition brusque).

Experiments on Alfv'en waves in high beta plasmas

NASA Astrophysics Data System (ADS)

Gekelman, Walter; Pribyl, Patrick; Cooper, Chris; Vincena, Stephen

2008-11-01

The propagation of Alfv'en waves in high beta plasmas is of great interest in solar wind studies as well as in astrophysical plasmas. Alfv'en wave propagation in a high beta plasma is studied on the axis of a toroidal device at UCLA. The vacuum vessel is 30 meters in circumference, 2 meters wide and 3 meters tall. The plasma has a cross sectional area of 20 cm^2 and can be as long as 120 m which is hundreds of parallel Alfv'en wavelengths. The waves are launched using two orthogonal 5-turn , 5.7 cm diameter loops. The AC currents (10 kHz < f < 250 kHz) to the loops are as high as 2 kA p-p, producing fields of 1 kG on the axis of the antenna. The antenna coils are independently driven such that waves with arbitrary polarization can be launched. Movable three axis magnetic pickup loops detect the wave and are used to construct field maps in the machine. Wave propagation results as a function of plasma beta and input wave energy will be presented.

Perpendicular and Parallel Ion Stochastic Heating by Kinetic Alfvén Wave Turbulence in the Solar Wind

NASA Astrophysics Data System (ADS)

Hoppock, I. W.; Chandran, B. D. G.

2017-12-01

The dissipation of turbulence is a prime candidate to explain the heating of collisionless plasmas like the solar wind. We consider the heating of protons and alpha particles using test particle simulations with a broad spectrum of randomly phased kinetic Alfvén waves (KAWs). Previous research extensively simulated and analytically considered stochastic heating at low plasma beta for conditions similar to coronal holes and the near-sun solar wind. We verify the analytical models of proton and alpha particle heating rates, and extend these simulations to plasmas with beta of order unity like in the solar wind at 1 au. Furthermore, we consider cases with very large beta of order 100, relevant to other astrophysical plasmas. We explore the parameter dependency of the critical KAW amplitude that breaks the gyro-center approximation and leads to stochastic gyro-orbits of the particles. Our results suggest that stochastic heating by KAW turbulence is an efficient heating mechanisms for moderate to high beta plasmas.

{beta}-Catenin regulates airway smooth muscle contraction.

PubMed

Jansen, Sepp R; Van Ziel, Anna M; Baarsma, Hoeke A; Gosens, Reinoud

2010-08-01

beta-Catenin is an 88-kDa member of the armadillo family of proteins that is associated with the cadherin-catenin complex in the plasma membrane. This complex interacts dynamically with the actin cytoskeleton to stabilize adherens junctions, which play a central role in force transmission by smooth muscle cells. Therefore, in the present study, we hypothesized a role for beta-catenin in the regulation of smooth muscle force production. beta-Catenin colocalized with smooth muscle alpha-actin (sm-alpha-actin) and N-cadherin in plasma membrane fractions and coimmunoprecipitated with sm-alpha-actin and N-cadherin in lysates of bovine tracheal smooth muscle (BTSM) strips. Moreover, immunocytochemistry of cultured BTSM cells revealed clear and specific colocalization of sm-alpha-actin and beta-catenin at the sites of cell-cell contact. Treatment of BTSM strips with the pharmacological beta-catenin/T cell factor-4 (TCF4) inhibitor PKF115-584 (100 nM) reduced beta-catenin expression in BTSM whole tissue lysates and in plasma membrane fractions and reduced maximal KCl- and methacholine-induced force production. These changes in force production were not accompanied by changes in the expression of sm-alpha-actin or sm-myosin heavy chain (MHC). Likewise, small interfering RNA (siRNA) knockdown of beta-catenin in BTSM strips reduced beta-catenin expression and attenuated maximal KCl- and methacholine-induced contractions without affecting sm-alpha-actin or sm-MHC expression. Conversely, pharmacological (SB-216763, LiCl) or insulin-induced inhibition of glycogen synthase kinase-3 (GSK-3) enhanced the expression of beta-catenin and augmented maximal KCl- and methacholine-induced contractions. We conclude that beta-catenin is a plasma membrane-associated protein in airway smooth muscle that regulates active tension development, presumably by stabilizing cell-cell contacts and thereby supporting force transmission between neighboring cells.

PERPENDICULAR ION HEATING BY LOW-FREQUENCY ALFVEN-WAVE TURBULENCE IN THE SOLAR WIND

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chandran, Benjamin D. G.; Germaschewski, Kai; Li Bo

We consider ion heating by turbulent Alfven waves (AWs) and kinetic Alfven waves (KAWs) with wavelengths (measured perpendicular to the magnetic field) that are comparable to the ion gyroradius and frequencies {omega} smaller than the ion cyclotron frequency {Omega}. We focus on plasmas in which {beta} {approx}< 1, where {beta} is the ratio of plasma pressure to magnetic pressure. As in previous studies, we find that when the turbulence amplitude exceeds a certain threshold, an ion's orbit becomes chaotic. The ion then interacts stochastically with the time-varying electrostatic potential, and the ion's energy undergoes a random walk. Using phenomenological arguments,more » we derive an analytic expression for the rates at which different ion species are heated, which we test by simulating test particles interacting with a spectrum of randomly phased AWs and KAWs. We find that the stochastic heating rate depends sensitively on the quantity {epsilon} = {delta}v {sub {rho}/}v{sub perpendicular}, where v{sub perpendicular} (v {sub ||}) is the component of the ion velocity perpendicular (parallel) to the background magnetic field B {sub 0}, and {delta}v {sub {rho}} ({delta}B {sub {rho}}) is the rms amplitude of the velocity (magnetic-field) fluctuations at the gyroradius scale. In the case of thermal protons, when {epsilon} << {epsilon}{sub crit}, where {epsilon}{sub crit} is a constant, a proton's magnetic moment is nearly conserved and stochastic heating is extremely weak. However, when {epsilon}>{epsilon}{sub crit}, the proton heating rate exceeds half the cascade power that would be present in strong balanced KAW turbulence with the same value of {delta}v {sub {rho}}, and magnetic-moment conservation is violated even when {omega} << {Omega}. For the random-phase waves in our test-particle simulations, {epsilon}{sub crit} = 0.19. For protons in low-{beta} plasmas, {epsilon} {approx_equal} {beta}{sup -1/2{delta}}B{sub {rho}/}B {sub 0}, and {epsilon} can exceed {epsilon}{sub crit} even when {delta}B{sub {rho}/}B {sub 0} << {epsilon}{sub crit}. The heating is anisotropic, increasing v {sup 2}{sub perpendicular} much more than v {sup 2}{sub ||} when {beta} << 1. (In contrast, at {beta} {approx}> 1 Landau damping and transit-time damping of KAWs lead to strong parallel heating of protons.) At comparable temperatures, alpha particles and minor ions have larger values of {epsilon} than protons and are heated more efficiently as a result. We discuss the implications of our results for ion heating in coronal holes and the solar wind.« less

Analysis of the plasma-wall interaction in the Heliotron E device

NASA Astrophysics Data System (ADS)

Motojima, O.; Mizuuchi, T.; Besshou, S.; Iiyoshi, A.; Uo, K.; Yamashina, T.; Mohri, M.; Satake, T.; Hashiba, M.; Amemiya, S.; Miwa, H.

1984-12-01

The plasma-wall interaction (PWI) of the currentless plasmas with temperature To, Tio ≤ 1.1 keV, density N¯e = (2-10)× 1013/cm3, and volume-averaged beta value of β$¯≤ 2% was investigated. We have observed that PWI took place mainly where the divertor field line intersected the chamber wall (called divertor traces). Boundary plasmas were measured with electrostatic probes, which showed the presence of the divertor region with the parameters in the range of Ned = 1010-1011/cm3 and Ted = 10-50 eV. Surface analysis techniques (ESCA, AES, and RBS) were applied to analyze the surface probes (Si, graphite and stainless steel) and the test pieces (SiC, TiC, and stainless steel), which were irradiated by plasmas for short and long times respectively.

Maternal plasma concentrations of beta-lipotrophin, beta-endorphin and gamma-lipotrophin throughout pregnancy.

PubMed

Browning, A J; Butt, W R; Lynch, S S; Shakespear, R A

1983-12-01

Plasma beta-LPH, beta-EP and gamma-LPH concentrations were measured by radioimmunoassay in 10 pregnant women from 12 weeks gestation until term and in nine women in the early follicular phase of the cycle. There was a progressive and significant rise in the concentration of all three peptides throughout pregnancy and by 32 weeks the concentrations of beta-LPH and beta-EP were greater than the corresponding concentrations in the follicular phase: gamma-LPH was greater than in the follicular phase by the end of pregnancy in those women who were delivered after 40 weeks. The ratio of beta-LPH to gamma-LPH did not change significantly throughout pregnancy, but there was a progressive fall in the beta-LPH/beta-EP ratio. The possible presence of a 'big LPH' to explain this finding is discussed.

Non-linear dynamics of compound sawteeth in tokamaks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahn, J.-H., E-mail: jae-heon.ahn@polytechnique.edu; Garbet, X.; Sabot, R.

2016-05-15

Compound sawteeth is studied with the XTOR-2F code. Non-linear full 3D magnetohydrodynamic simulations show that the plasma hot core is radially displaced and rotates during the partial crash, but is not fully expelled out of the q = 1 surface. Partial crashes occur when the radius of the q = 1 surface exceeds a critical value, at fixed poloidal beta. This critical value depends on the plasma elongation. The partial crash time is larger than the collapse time of an ordinary sawtooth, likely due to a weaker diamagnetic stabilization. This suggests that partial crashes result from a competition between destabilizing effects such as themore » q = 1 radius and diamagnetic stabilization.« less

A non-linear theory of the parallel firehose and gyrothermal instabilities in a weakly collisional plasma

NASA Astrophysics Data System (ADS)

Rosin, M. S.; Schekochihin, A. A.; Rincon, F.; Cowley, S. C.

2011-05-01

Weakly collisional magnetized cosmic plasmas have a dynamical tendency to develop pressure anisotropies with respect to the local direction of the magnetic field. These anisotropies trigger plasma instabilities at scales just above the ion Larmor radius ρi and much below the mean free path λmfp. They have growth rates of a fraction of the ion cyclotron frequency, which is much faster than either the global dynamics or even local turbulence. Despite their microscopic nature, these instabilities dramatically modify the transport properties and, therefore, the macroscopic dynamics of the plasma. The non-linear evolution of these instabilities is expected to drive pressure anisotropies towards marginal stability values, controlled by the plasma beta βi. Here this non-linear evolution is worked out in an ab initio kinetic calculation for the simplest analytically tractable example - the parallel (k⊥= 0) firehose instability in a high-beta plasma. An asymptotic theory is constructed, based on a particular physical ordering and leading to a closed non-linear equation for the firehose turbulence. In the non-linear regime, both the analytical theory and the numerical solution predict secular (∝t) growth of magnetic fluctuations. The fluctuations develop a k-3∥ spectrum, extending from scales somewhat larger than ρi to the maximum scale that grows secularly with time (∝t1/2); the relative pressure anisotropy (p⊥-p∥)/p∥ tends to the marginal value -2/βi. The marginal state is achieved via changes in the magnetic field, not particle scattering. When a parallel ion heat flux is present, the parallel firehose mutates into the new gyrothermal instability (GTI), which continues to exist up to firehose-stable values of pressure anisotropy, which can be positive and are limited by the magnitude of the ion heat flux. The non-linear evolution of the GTI also features secular growth of magnetic fluctuations, but the fluctuation spectrum is eventually dominated by modes around a maximal scale ˜ρilT/λmfp, where lT is the scale of the parallel temperature variation. Implications for momentum and heat transport are speculated about. This study is motivated by our interest in the dynamics of galaxy cluster plasmas (which are used as the main astrophysical example), but its relevance to solar wind and accretion flow plasmas is also briefly discussed.

Steady State Model for Solar Coronal Loops

NASA Astrophysics Data System (ADS)

Sugiyama, L.; Asgari-Targhi, M.

2017-12-01

Solar coronal loops on the surface of the sun provide background magnetic and plasma structures for the release of a significant amount of the sun's energy, through energetic solar flares and coronal mass ejections and more gradual processes. Understanding their steady states is the first step in understanding loop dynamics. A consistent MHD steady state model, for a curved magnetic flux rope that contains plasma, has been developed[1] for simple coronal loops with both ends anchored in the photosphere. Plasma pressure or current makes the loop unstable to expansion in major radius and must be balanced by external forces, such as the solar gravity. The MHD momentum equation has a well defined small parameter ordering in the loop inverse aspect ratio ɛ=a/Ro (minor/major radius). Different types of common coronal loops fall in different parameter regimes, determined by the relative values of the plasma beta β=po/(Bo2/2μo), the MHD gravity parameter Ĝ≡ga/vA2 (the gravitational acceleration g normalized to the minor radius a and shear Alfvén velocity vA), and ɛ. The largest possible gravity, Ĝ ɛ1β, corresponds to the largest loops because it reduces the plasma density at the top of the loop exponentially compared to its lower ends, reducing the downward gravitational force -ρĜ there. The thin loops that are ubiquitous in solar active regions have ``high'' beta, β ɛ1, for ɛ≃0.02, and fit the predicted model scalings. The thicker loops that can give rise to flares and CMEs have ``low'' beta, β ɛ2. Cool loops, such as solar filaments outside active regions, that have a central pressure lower than that of the surrounding corona would have the strongest stability against radial expansion. The model raises a number of questions about the connection of loops to the photosphere and the force-free nature of the magnetic field there. [1] L. Sugiyama, M. Asgari-Targhi, Phys. Plasmas 24, 022904 (2017).

Beta-endorphin-induced inhibition and stimulation of insulin secretion in normal humans is glucose dependent.

PubMed

Giugliano, D; Cozzolino, D; Salvatore, T; Torella, R; D'Onofrio, F

1988-09-01

This study evaluated the effect of human beta-endorphin on pancreatic hormone levels and their responses to nutrient challenges in normal subjects. Infusion of 0.5 mg/h beta-endorphin caused a significant rise in plasma glucose concentrations preceded by a significant increase in peripheral glucagon levels. No changes occurred in the plasma concentrations of insulin and C-peptide. Acute insulin and C-peptide responses to intravenous pulses of different glucose amounts (0.33 g/kg and 5 g) and arginine (3 g) were significantly reduced by beta-endorphin infusion (P less than .01). This effect was associated with a significant reduction of the glucose disappearance rates, suggesting that the inhibition of insulin was of biological relevance. beta-Endorphin also inhibited glucose suppression of glucagon levels and augmented the glucagon response to arginine. To verify whether the modification of prestimulus glucose level could be important in these hormonal responses to beta-endorphin, basal plasma glucose concentrations were raised by a primed (0.5 g/kg) continuous (20 mg kg-1.min-1) glucose infusion. After stabilization of plasma glucose levels (350 +/- 34 mg/dl, t = 120 min), beta-endorphin infusion caused an immediate and marked increase in plasma insulin level (peak response 61 +/- 9 microU/ml, P less than .01), which remained elevated even after the discontinuation of opioid infusion. Moreover, the acute insulin response to a glucose pulse (0.33 g/kg i.v.) given during beta-endorphin infusion during hyperglycemia was significantly higher than the response obtained during euglycemia (171 +/- 32 vs. 41 +/- 7 microU/ml, P less than .01).(ABSTRACT TRUNCATED AT 250 WORDS)

Fasting in king penguin. II. Hormonal and metabolic changes during molt.

PubMed

Cherel, Y; Leloup, J; Le Maho, Y

1988-02-01

The coincidence of fast and molt in penguins is an interesting condition for investigating the factors controlling protein metabolism; avian molt involves the utilization of amino acids for synthesis of new feathers, whereas a major factor for adaptation to fasting in birds, as for mammals, is reduction in net protein breakdown. Hormonal and biochemical changes were studied in seven molting king penguins. Their initial body mass was 18 kg. It decreased by 58% over 41 days of fasting. Feather synthesis lasted for the first 3 wk of the fast. It was marked by plasma concentrations of alanine and uric acid 1.5 to 2 times those for nonmolting fast, and plasma thyroxine was increased five times. At the completion of molt all these values returned to levels comparable to those in nonmolting fast. As indicated by high plasma levels of beta-hydroxybutyrate, lipid stores were mobilized readily during molting. The fast ended by a phase of enhancement in protein utilization that was characterized by a fivefold increase in uricacidemia and coincided with an 80% drop in plasma beta-hydroxybutyrate and a fourfold increase in plasma corticosterone. These data suggest that two different hormones control the two successive periods marked by an increased protein mobilization during the molting fast, i.e., thyroxine during feather growth and corticosterone toward the end of the fast, when the molt is completed.

A Multifunctional Bread Rich in Beta Glucans and Low in Starch Improves Metabolic Control in Type 2 Diabetes: A Controlled Trial

PubMed Central

Tessari, Paolo; Lante, Anna

2017-01-01

Design: Functional foods may be useful for people with diabetes. The soluble fibers beta glucans can modify starch digestion and improve postprandial glucose response. We analyzed the metabolic effects of a specifically designed ‘functional’ bread, low in starch, rich in fibers (7 g/100 g), with a beta glucan/starch ratio of (7.6:100, g/g), in people with type 2 diabetes mellitus. Methods: Clinical and metabolic data from two groups of age-, sex- and glycated hemoglobin-matched diabetic subjects, taking either the functional bread or regular white bread, over a roughly six-month observation period, were retrieved. Results: Bread intake did not change during the trial. The functional bread reduced glycated hemoglobin by ~0.5% (absolute units) vs. pre-treatment values (p = 0.028), and by ~0.6% vs. the control group (p = 0.027). Post-prandial and mean plasma glucose was decreased in the treatment group too. Body weight, blood pressure and plasma lipids did not change. The acceptance of the functional bread was good in the majority of subjects, except for taste. Conclusions: A starch-restricted, fiber-rich functional bread, with an increased beta glucan/starch ratio, improved long term metabolic control, and may be indicated in the dietary treatment of type 2 diabetes. PMID:28304350

Validation of Spectral Analysis as a Noninvasive Tool to Assess Autonomic Regulation of Cardiovascular Function

NASA Technical Reports Server (NTRS)

Knapp, Charles F.; Evans, Joyce M.

1996-01-01

A major focus of our program has been to develop a sensitive noninvasive procedure to quantify early weightlessness-induced changes in cardiovascular function or potential dysfunction. Forty studies of healthy young volunteers (10 men and 10 women, each studied twice) were conducted to determine changes in the sympatho-vagal balance of autonomic control of cardiovascular regulation during graded headward and footward blood volume shifts. Changes in sympatho-vagal balance were classified by changes in the mean levels and spectral content of cardiovascular variables and verified by changes in circulating levels of catecholamines and pancreatic polypeptide. Possible shifts in intra/extravascular fluid were assessed from changes in hematocrit and plasma mass density while changes in the stimulus to regulate plasma volume were determined from Plasma Renin Activity (PRA). Autonomic blockade was used to unmask the relative contribution of sympathetic and parasympathetic efferent influences in response to 10 min each of 0, 20 and 40 mmHg Lower Body Negative Pressure (LBNP) and 15 and 30 mmHg Positive Pressure (LBPP). The combination of muscarinic blockade with graded LBNP and LBPP was used to evoke graded increases and decreases in sympathetic activity without parasympathetic contributions. The combination of beta blockade with graded LBNP and LBPP was used to produce graded increases and decreases in parasympathetic activity without beta sympathetic contributions. Finally, a combination of both beta and muscarinic blockades with LBNP and LBPP was used to determine the contribution from other, primarily alpha adrenergic, sources. Mean values, spectral analyses and time frequency analysis of R-R interval (HR), Arterial Pressure (AP), peripheral blood flow (RF), Stroke Volume (SV) and peripheral resistance (TPR) were performed for all phases of the study. Skin blood Flow (SF) was also measured in other studies and similarly analyzed. Spectra were examined for changes in three frequency regions (low 0.006 - 0.005 Hz (LF), mid 0.05 - 0.15 Hz (W), and high 0.15 - 0.45 Hz (EF)). The primary objective of the study was to indicate which changes in the mean values and/or spectra of cardiovascular variables consistently correlated with changes in sympatho-vagal balance in response to headward and footward fluid shifts. A secondaey objective was to quantify the vascular and extravascular fluid shifts evoked by LBNP and LBPP. The principal hypothesis being tested was that headward fluid shifts would evoke an increase in parasympathetic activity and footward fluid shifts would evoke an increase in sympathetic activity both of which would be detected by spectral analysis and verified by circulating hormones. Hematocrit (HCT), plasma mass density and plasma renin activity increased with muscarinic blockade and with LBNP, a response indicative of a plasma shift to extravascular spaces. Beta blockade alone or after muscarinic blockade had no effect on HCT or plasma mass density. With respect to intravascular fluid volume distribution, LBNP and LBPP produced sufficient upper body vascular fluid shifts to evoke appropriate autonomic regulatory responses.

The relationship of plasma catestatin concentrations with metabolic and vascular parameters in untreated hypertensive patients: Influence on high-density lipoprotein cholesterol

PubMed Central

Durakoğlugil, Murtaza Emre; Ayaz, Teslime; Kocaman, Sinan Altan; Kırbaş, Aynur; Durakoğlugil, Tuğba; Erdoğan, Turan; Çetin, Mustafa; Şahin, Osman Zikrullah; Çiçek, Yüksel

2015-01-01

Objective: Catestatin has several cardiovascular actions, in addition to diminished sympatho-adrenal flow. Decreased plasma catestatin levels may reflect a predisposition for the development of hypertension and metabolic disorders. We planned to investigate the possible roles of catestatin in untreated hypertensive patients. As a secondary objective, we compared catestatin concentrations of healthy subjects with those of hypertensive patients in order to understand whether catestatin is increased reactively or diminished at onset. Methods: Our study was cross-sectional and observational. The patient group, comprising 109 consecutive untreated hypertensive patients without additional systemic or coronary heart disease, underwent evaluations of plasma catestatin, waist circumference, lipid parameters, left ventricular mass, carotid intima-media thickness, and flow-mediated dilation of the brachial artery. Additionally, we measured catestatin concentrations of 38 apparently healthy subjects without any disease using a commercial enzyme-linked immunosorbent assay kit. Results: We documented increased catestatin concentrations in previously untreated hypertensive patients compared to healthy controls (2.27±0.83 vs. 1.92±0.49 ng/mL, p=0.004). However, this association became insignificant after adjustments for age, gender, height, and weight. Within the patient group, catestatin levels were significantly higher in females. Among all study parameters, age, high-density lipoprotein cholesterol (HDL-C) correlated positively to plasma catestatin, whereas triglycerides, hemoglobin, and left ventricular mass correlated negatively to plasma catestatin. We could not detect an association between vascular parameters and catestatin. Catestatin levels were significantly elevated with increasing HDL-C (1.91±0.37, 2.26±0.79, and 3.1±1.23 ng/mL in patients with HDL-C <40, 40-60, and >60 mg/dL, respectively). Multiple linear regression analysis revealed age (beta: 0.201, p=0.041) and HDL-C (beta: 0.390, p<0.001) as independent correlates of plasma catestatin concentration. Additionally, male gender (beta:-0.330, p=0.001) and plasma catestatin (beta: 0.299, p=0.002) were significantly associated with HDL-C concentrations. Conclusion: We documented that plasma catestatin is an independent predictor of high-density lipoprotein cholesterol. In addition to antihypertensive effects, catestatin appears to be related to improved lipid and metabolic profiles. Coexistence of low catestatin levels with low HDL-C may provide a probable mechanism for the predictive value of low HDL-C for increased hypertension and cardiovascular events. PMID:25538000

Influence of insulin on beta-endorphin plasma levels in obese and normal weight subjects.

PubMed

Brunani, A; Pincelli, A I; Pasqualinotto, L; Tibaldi, A; Baldi, G; Scacchi, M; Fatti, L M; Cavagnini, F

1996-08-01

To establish the possible role of hyperinsulinemia in the elevation of plasma beta-endorphin (beta-EP) levels observed in obese patients after an oral glucose load. Oral glucose tolerance test (OGTT) and euglycemic-hyperinsulinemic clamp. Two groups of six (age: 22-39 y, BMI: 30-48 kg/m2) and eight obese men (age: 18-37 y, BMI: 35-45 kg/m2), respectively, and five normal weight healthy men (age: 22-30 y, BMI 22-23 kg/m2). Glucose, insulin and beta-EP levels at baseline and every 30 min until 180 min during the OGTT; glucose, insulin, C-peptide and beta-EP concentrations at baseline and in steady state condition (i.e. during the last 30 min of insulin infusion) in the euglycemic-hyperinsulinemic clamp studies. In the six obese patients undergoing the OGTT a significant elevation of beta-EP plasma levels was observed between 60 and 90 min after glucose ingestion. In the clamp studies no significant differences in beta-EP plasma levels, blood glucose and serum insulin were observed between obese and normal weight subjects both at baseline and at steady state. A markedly diminished insulin sensitivity along with a lower inhibition of C-peptide during insulin infusion was observed in obese patients compared to control subjects. A rise in serum insulin levels unaccompanied by a concomitant increase in blood glucose concentration is unable to elicit a beta-EP response in obese patients.

Suppression of diamagnetism by neutrals pressure in partially ionized, high-beta plasma

NASA Astrophysics Data System (ADS)

Shinohara, Shunjiro; Kuwahara, Daisuke; Yano, Kazuki; Fruchtman, Amnon

2016-12-01

Suppression of diamagnetism in a partially ionized plasma with high beta was experimentally investigated by the use of Langmuir and Hall sensor probes, focusing on a neutrals pressure effect. The plasma beta, which is the ratio of plasma to vacuum magnetic pressures, varied from ˜1% to >100% while the magnetic field varied from ˜120 G to ˜1 G. Here, a uniform magnetized argon plasma was operated mostly in an inductive mode, using a helicon plasma source of the Large Helicon Plasma Device [S. Shinohara et al., Phys. Plasmas 16, 057104 (2009)] with a diameter of 738 mm and an axial length of 4860 mm. Electron density varied from 5 × 1015 m-3 to <3 × 1018 m-3, while an argon fill pressure was varied from ˜0.02 Pa to 0.75 Pa as well as the magnetic field mentioned above, with the fixed radio frequency (rf) and power of 7 MHz and ˜3.5 kW, respectively. The observed magnetic field reduction rate, a decrease of the magnetic field divided by the vacuum one, was up to 18%. However, in a certain parameter regime, where the product of ion and electron Hall terms is a key parameter, the measured diamagnetic effect was smaller than that expected by the plasma beta. This suppressed diamagnetism is explained by the neutrals pressure replacing magnetic pressure in balancing plasma pressure. Diamagnetism is weakened if neutrals pressure is comparable to the plasma pressure and if the coupling of plasma and neutrals pressures by ion-neutral collisions is strong enough.

High-beta extended MHD simulations of stellarators

NASA Astrophysics Data System (ADS)

Bechtel, T. A.; Hegna, C. C.; Sovinec, C. R.; Roberds, N. A.

2016-10-01

The high beta properties of stellarator plasmas are studied using the nonlinear, extended MHD code NIMROD. In this work, we describe recent developments to the semi-implicit operator which allow the code to model 3D plasma evolution with better accuracy and efficiency. The configurations under investigation are an l=2, M=5 torsatron with geometry modeled after the Compact Toroidal Hybrid (CTH) experiment and an l=2, M=10 torsatron capable of having vacuum rotational transform profiles near unity. High-beta plasmas are created using a volumetric heating source and temperature dependent anisotropic thermal conduction and resistivity. To reduce computation expenses, simulations are initialized from stellarator symmetric pseudo-equilibria by turning on symmetry breaking modes at finite beta. The onset of MHD instabilities and nonlinear consequences are monitored as a function of beta as well as the fragility of the magnetic surfaces. Research supported by US DOE under Grant No. DE-FG02-99ER54546.

Involvement of tumour necrosis factor-α in Clostridium perfringens β-toxin-induced plasma extravasation in mice

PubMed Central

Nagahama, M; Kihara, A; Kintoh, H; Oda, M; Sakurai, J

2008-01-01

Background and purpose: Clostridium perfringens beta-toxin, an important agent of necrotic enteritis, causes plasma extravasation due to the release of a tachykinin NK1 receptor agonist in mouse skin. In this study, we investigated the role of cytokines in beta-toxin-induced plasma extravasation. Experimental approach: Male Balb/c, C3H/HeN and C3H/HeJ mice were anaesthetized with pentobarbitone and beta-toxin was injected i.d. into shaved dorsal skin. SR140333, capsaicin, chlorpromazine and pentoxifylline were given as pretreatment when required before the injection of the toxin. Cytokines in the dorsal skin were measured by ELISA. Key results: Injection (i.d.) of beta-toxin induced a dose-dependent increase in dermal TNF-α and interleukin (IL)-1β levels with a concomitant increase in plasma extravasation, but not the release of IL-6. SR140333 and capsaicin significantly inhibited the toxin-induced release of TNF-α and IL-1β. The plasma extravasation and the release of TNF-α induced by beta-toxin were significantly inhibited by chlorpromazine and pentoxifylline which inhibit the release of TNF-α. The toxin-induced plasma extravasation in mouse skin was attenuated by pretreatment with a monoclonal antibody against TNF-α, but not anti-IL-1β. Furthermore, the toxin caused an increase in plasma extravasation in both C3H/HeN (TLR4-intact) and C3H/HeJ (TLR4-deficient) mice. In C3H/HeN mice, the toxin-induced leakage was not inhibited by pretreatment with anti-TLR4/MD-2 antibody. Conclusions and implications: These observations show that beta-toxin-induced plasma extravasation in mouse skin is related to the release of TNF-α via the mechanism involving tachykinin NK1 receptors, but not via TLR4. PMID:18264118

DOE Office of Scientific and Technical Information (OSTI.GOV)

A. Brooks; A.H. Reiman; G.H. Neilson

High-beta, low-aspect-ratio (compact) stellarators are promising solutions to the problem of developing a magnetic plasma configuration for magnetic fusion power plants that can be sustained in steady-state without disrupting. These concepts combine features of stellarators and advanced tokamaks and have aspect ratios similar to those of tokamaks (2-4). They are based on computed plasma configurations that are shaped in three dimensions to provide desired stability and transport properties. Experiments are planned as part of a program to develop this concept. A beta = 4% quasi-axisymmetric plasma configuration has been evaluated for the National Compact Stellarator Experiment (NCSX). It has amore » substantial bootstrap current and is shaped to stabilize ballooning, external kink, vertical, and neoclassical tearing modes without feedback or close-fitting conductors. Quasi-omnigeneous plasma configurations stable to ballooning modes at beta = 4% have been evaluated for the Quasi-Omnigeneous Stellarator (QOS) experiment. These equilibria have relatively low bootstrap currents and are insensitive to changes in beta. Coil configurations have been calculated that reconstruct these plasma configurations, preserving their important physics properties. Theory- and experiment-based confinement analyses are used to evaluate the technical capabilities needed to reach target plasma conditions. The physics basis for these complementary experiments is described.« less

Predictive modelling of JT-60SA high-beta steady-state plasma with impurity accumulation

NASA Astrophysics Data System (ADS)

Hayashi, N.; Hoshino, K.; Honda, M.; Ide, S.

2018-06-01

The integrated modelling code TOPICS has been extended to include core impurity transport, and applied to predictive modelling of JT-60SA high-beta steady-state plasma with the accumulation of impurity seeded to reduce the divertor heat load. In the modelling, models and conditions are selected for a conservative prediction, which considers a lower bound of plasma performance with the maximum accumulation of impurity. The conservative prediction shows the compatibility of impurity seeding with core plasma with high-beta (β N  >  3.5) and full current drive conditions, i.e. when Ar seeding reduces the divertor heat load below 10 MW m‑2, its accumulation in the core is so moderate that the core plasma performance can be recovered by additional heating within the machine capability to compensate for Ar radiation. Due to the strong dependence of accumulation on the pedestal density gradient, high separatrix density is important for the low accumulation as well as the low divertor heat load. The conservative prediction also shows that JT-60SA has enough capability to explore the divertor heat load control by impurity seeding in high-beta steady-state plasmas.

The ionization length in plasmas with finite temperature ion sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jelic, N.; Kos, L.; Duhovnik, J.

2009-12-15

The ionization length is an important quantity which up to now has been precisely determined only in plasmas which assume that the ions are born at rest, i.e., in discharges known as 'cold ion-source' plasmas. Presented here are the results of our calculations of the ionization lengths in plasmas with an arbitrary ion source temperature. Harrison and Thompson (H and T) [Proc. Phys. Soc. 74, 145 (1959)] found the values of this quantity for the cases of several ion strength potential profiles in the well-known Tonks-Langmuir [Phys. Rev. 34, 876 (1929)] discharge, which is characterized by 'cold' ion temperature. Thismore » scenario is also known as the 'singular' ion-source discharge. The H and T analytic result covers cases of ion sources proportional to exp(betaPHI) with PHI the normalized plasma potential and beta=0,1,2 values, which correspond to particular physical scenarios. Many years following H and T's work, Bissell and Johnson (B and J) [Phys. Fluids 30, 779 (1987)] developed a model with the so-called 'warm' ion-source temperature, i.e., 'regular' ion source, under B and J's particular assumption that the ionization strength is proportional to the local electron density. However, it appears that B and J were not interested in determining the ionization length at all. The importance of this quantity to theoretical modeling was recognized by Riemann, who recently answered all the questions of the most advanced up-to-date plasma-sheath boundary theory with cold ions [K.-U. Riemann, Phys. Plasmas 13, 063508 (2006)] but still without the stiff warm ion-source case solution, which is highly resistant to solution via any available analytic method. The present article is an extension of H and T's results obtained for a single point only with ion source temperature T{sub n}=0 to arbitrary finite ion source temperatures. The approach applied in this work is based on the method recently developed by Kos et al. [Phys. Plasmas 16, 093503 (2009)].« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peng, Y.K.M.; Strickler, D.J.

The spherical torus is a very small aspect ratio (A < 2) confinement concept obtained by retaining only the indispensable components inboard to the plasma torus. MHD equilibrium calculations show that spherical torus plasmas with safety factor q > 2 are characterized by high toroidal beta (..beta../sub t/ > 0.2), low poloidal beta (..beta../sub p/ < 0.3), naturally large elongation (kappa greater than or equal to 2), large plasma current with I/sub p//(aB/sub t0/) up to about 7 MA/mT, strong paramagnetism (B/sub t//B/sub t0/ > 1.5), and strong plasma helicity (F comparable to THETA). A large near-omnigeneous region is seenmore » at the large-major-radius, bad-curvature region of the plasma in comparison with the conventional tokamaks. These features combine to engender the spherical torus plasma in a unique physics regime which permits compact fusion at low field and modest cost. Because of its strong paramagnetism and helicity, the spherical torus plasma shares some of the desirable features of spheromak and reversed-field pinch (RFP) plasmas, but with tokamak-like confinement and safety factor q. The general class of spherical tori, which includes the spherical tokamak (q > 1), the spherical pinch (1 > q > O), and the spherical RFP (q < O), have magnetic field configurations unique in comparison with conventional tokamaks and RFPs. 22 refs., 12 figs.« less

The Pioneer 10 plasma analyzer results at Jupiter

NASA Technical Reports Server (NTRS)

Wolfe, J. H.

1975-01-01

Results are reported for the Pioneer 10 plasma-analyzer experiment at Jupiter. The analyzer system consisted of dual 90-deg quadrispherical electrostatic analyzers, multiple charged-particle detectors, and attendant electronics; it was capable of determining the incident plasma-distribution parameters over the energy range from 100 to 18,000 eV for protons and from approximately 1 to 500 eV for electrons. Data are presented on the interaction between the solar wind and the Jovian magnetosphere, the interplanetary ion flux, observations of the magnetosheath plasma, and traversals of the bow shock and magnetopause. Values are estimated for the proton isotropic temperature, number density, and bulk velocity within the magnetosheath flow field as well as for the beta parameter, ion number density, and magnetic-energy density of the magnetospheric plasma. It is argued that Jupiter has a reasonably thick magnetosphere somewhat similar to earth's except for the vastly different scale sizes involved.

Structure of the reconnection layer and the associated slow shocks: Two-dimensional simulations of a Riemann problem

NASA Astrophysics Data System (ADS)

Cremer, Michael; Scholer, Manfred

2000-12-01

The kinetic structure of the reconnection layer in the magnetotail is investigated by two-dimensional hybrid simulations. As a proxy, the solution of the Riemann problem of the collapse of a current sheet with a normal magnetic field component is considered for two cases of the plasma beta (particle to magnetic field pressure): β=0.02 and β=0.002. The collapse results in an expanding layer of compressed and heated plasma, which is accelerated up to the Alfvén speed vA. The boundary layer separating this hot reconnection like layer from the cold lobe plasma is characterized by a beam of back-streaming ions with a field-aligned bulk speed of ~=2vA relative to the cold lobe ion population at rest. As a consequence, obliquely propagating waves are excited via the electromagnetic ion/ion cyclotron instability, which led to perpendicular heating of the ions in the boundary layer as well as further outside the layer in the lobe. In both regions, waves are found which propagate almost parallel to the magnetic field and which are identified as Alfvén ion cyclotron (AIC) waves. These waves are excited by the temperature anisotropy instability. The temperature anisotropy increases with decreasing plasma beta. Thus the anisotropy threshold of the instability is exceeded even in the case of a rather small beta value. The AIC waves, when convected downstream of what can be defined as the the slow shock, make an important contribution to the ion thermalization process. More detailed information on the dissipation process in the slow shocks is gained by analyzing individual ion trajectories.

Current and high-β sheets in CIR streams: statistics and interaction with the HCS and the magnetosphere

NASA Astrophysics Data System (ADS)

Potapov, A. S.

2018-04-01

Thirty events of CIR streams (corotating interaction regions between fast and slow solar wind) were analyzed in order to study statistically plasma structure within the CIR shear zones and to examine the interaction of the CIRs with the heliospheric current sheet (HCS) and the Earth's magnetosphere. The occurrence of current layers and high-beta plasma sheets in the CIR structure has been estimated. It was found that on average, each of the CIR streams had four current layers in its structure with a current density of more than 0.12 A/m2 and about one and a half high-beta plasma regions with a beta value of more than five. Then we traced how and how often the high-speed stream associated with the CIR can catch up with the heliospheric current sheet (HCS) and connect to it. The interface of each fourth CIR stream coincided in time within an hour with the HCS, but in two thirds of cases, the CIR connection with the HCS was completely absent. One event of the simultaneous observation of the CIR stream in front of the magnetosphere by the ACE satellite in the vicinity of the L1 libration point and the Wind satellite in the remote geomagnetic tail was considered in detail. Measurements of the components of the interplanetary magnetic field and plasma parameters showed that the overall structure of the stream is conserved. Moreover, some details of the fine structure are also transferred through the magnetosphere. In particular, the so-called "magnetic hole" almost does not change its shape when moving from L1 point to a neighborhood of L2 point.

Plasma beta-endorphin, beta-lipotropin and corticotropin in polycystic ovarian disease.

PubMed

Laatikainen, T; Salminen, K; Virtanen, T; Apter, D

1987-04-01

In 9 women with polycystic ovarian disease (PCOD) and in 11 control subjects at the follicular phase of the normal cycle, blood samples were collected at 15-min intervals during a 2 h period of bed rest for the assay of beta-endorphin, beta-lipotropin, corticotropin, cortisol and prolactin. During the study period, the plasma levels of these hormones decreased more significantly in the PCOD than in the control group, suggesting that the PCOD patients had a more significant stress response to the puncture of the vein than the control subjects. The second hour of the study period was considered to represent resting levels of hormones. The mean resting levels (+/- S.E.) of the hormones between the PCOD and control groups, respectively, were as follows: beta-E, 2.0 +/- 0.4 vs. 1.1 +/- 0.1 pmol/l, p less than 0.05; beta-LPH, 3.4 +/- 0.6 vs. 2.1 +/- 0.5 pmol/l, N.S.; corticotropin, 2.0 +/- 0.3 vs. 1.1 +/- 0.5 pmol/l, p less than 0.05; cortisol, 176 +/- 24 vs. 128 +/- 16, N.S.; and prolactin; 3.9 +/- 0.6 vs. 5.6 +/- 1.2 ng/ml, N.S. These results confirm the previous findings on increased circulating levels of beta-E in PCOD. A concomitant increase of the plasma level of corticotropin suggests that the basal secretion of both beta-E and corticotropin from the anterior pituitary gland is increased in women with PCOD.

Bootstrap current in a tokamak

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kessel, C.E.

1994-03-01

The bootstrap current in a tokamak is examined by implementing the Hirshman-Sigmar model and comparing the predicted current profiles with those from two popular approximations. The dependences of the bootstrap current profile on the plasma properties are illustrated. The implications for steady state tokamaks are presented through two constraints; the pressure profile must be peaked and {beta}{sub p} must be kept below a critical value.

High- β equilibrium and ballooning stability of the low aspect ratio CNT stellarator

DOE PAGES

Hammond, K. C.; Lazerson, S. A.; Volpe, F. A.

2017-04-07

In the paper, the existence and ballooning-stability of low aspect ratio stellarator equilibria is predicted for the Columbia Neutral Torus (CNT) with the aid of 3D numerical tools. In addition to having a low aspect ratio, CNT is characterized by a low magnetic field and small plasma volume. Also, highly overdense plasmas were recently heated in CNT by means of microwaves. These characteristics suggest that CNT might attain relatively high values of plasma beta and thus be of use in the experimental study of stellarator stability to high-beta instabilities such as ballooning modes. As a first step in that direction,more » here the ballooning stability limit is found numerically. Depending on the particular magnetic configuration we expect volume-averaged β limits in the range 0.9%–3.0%, and possibly higher, and observe indications of a second region of ballooning stability. As the aspect ratio is reduced, stability is found to increase in some configurations and decrease in others. Energy-balance estimates using stellarator scaling laws indicate that the lower β limit may be attainable with overdense heating at powers of 40 to 100 kW. The present study serves the additional purpose of testing VMEC and other stellarator codes at high values of β and at low aspect ratios. For this reason, the study was carried out both for free boundary, for maximum fidelity to experiment, as well as with a fixed boundary, as a numerical test.« less

Plasma convection and ion beam generation in the plasma sheet boundary layer

NASA Technical Reports Server (NTRS)

Moghaddam-Taaheri, E.; Goertz, C. K.; Smith, R. A.

1991-01-01

Because of the dawn-dusk electric field E(dd), plasma in the magnetotail convects from the lobe toward the central plasma sheet (CPS). In the absence of space or velocity diffusion due to plasma turbulence, convection would yield a steady state distribution function f = V exp (-2/3) g(v exp 2 V exp 2/3), where V is the flux tube volume. Starting with such a distribution function and a plasma beta which varies from beta greater than 1 in the CPS to beta much smaller than 1 in the lobe, the evolution of the ion distribution function was studied considering the combined effects of ion diffusion by kinetic Alfven waves (KAW) in the ULF frequency range (1-10 mHz) and convection due to E(dd) x B drift in the plasma sheet boundary layer (PSBL) and outer central plasma sheet (OCPS). The results show that, during the early stages after launching the KAWs, a beamlike ion distribution forms in the PSBL and at the same time the plasma density and temperature decrease in the OCPS. Following this stage, ions in the beams convect toward the CPS resulting in an increase of the plasma temperature in the OCPS.

Beta blocker effects on plasma homocysteine levels in patients with hypertension.

PubMed

Atar, Ilyas; Korkmaz, Mehmet Emin; Demircan, Senol; Atar, Inci Asli; Bozbaş, Hüseyin; Aydinalp, Alp; Ozin, Bülent; Yildirir, Aylin; Müderrisoğlu, Haldun

2005-08-01

Recent studies have shown that hyperhomocysteinemia might play a role in the pathogenesis of hypertension. The effects of antihypertensive agents on plasma homocysteine levels have not been tested extensively. We investigated the effects of beta-blocker therapy on homocysteine levels in patients with hypertension. In the study, 120 patients with newly diagnosed hypertension were enrolled. All patients received metoprolol succinate 100 mg/day initially. If blood pressure was above normal on the 15th day of follow-up, the metoprolol dosage was doubled. Before initiation of the antihypertensive medication and after the fourth month of treatment, homocysteine levels were measured. Of the 120 patients enrolled, 39 could not complete the study. Homocysteine levels decreased significantly by the end of the fourth month when compared with basal values (13.5+/-4.5 micromol/l versus 12.4+/-4.9 micromol/l; P = 0.001). There was no relation between homocysteine level and blood pressure control. There was a significant decrease in homocysteine levels in the women treated in this study (P = 0.001); however, this effect was absent in men (P = 0.185). We demonstrate that metoprolol succinate treatment significantly decreases plasma homocysteine levels in patients with hypertension, especially in women.

Mefloquine pharmacokinetics in healthy subjects and in peptic ulcer patients after cimetidine administration.

PubMed

Kolawole, J A; Mustapha, A; Abudu-Aguye, I; Ochekpe, N

2000-01-01

The pharmacokinetics of orally administered mefloquine were determined in six healthy male subjects and in six ulcer patients before and after a 3-day course of cimetidine (400 mg morning and evening). Peak plasma concentrations Cmax and AUC0-infinity were similarly and significantly (P < 0.05) increased after cimetidine pretreatement in both healthy subjects and peptic ulcer patients Cmax was increased by 42.4% and 20.5% while AUC0-infinity was increased by 37.5% in healthy and peptic ulcer subjects respectively. The values of t1/2ab absorption and t1/2 beta elimination, total crearance CLT/F and volume of distribution were altered to varying levels after cimetidine treatment but the changes were not statistically significant in both healthy and peptic ulcer subjects. The established long t1/2 beta and this apparent interaction between mefloquine and cimetidine which resulted in increased mefloquine plasma concentration might be of clinical significant in patients with neurological/psychiatric history.

Stability of hot electron plasma in the ELMO bumpy torus

NASA Astrophysics Data System (ADS)

Tsang, K. T.; Cheng, C. Z.

The stability of a hot electron plasma in the ELMO Bumpy Torus was investigated using two different models. In the first model, where the hot electron distribution function is assumed to be a delta function in the perpendicular velocity, a stability boundary in addition to those discussed by Nelson and by Van Dam and Lee is found. In the second model, where the hot electron distribution function is assumed to be a Maxwellian in the perpendicular velocity, stability boundaries significantly different from those of the first model are found. Coupling of the Nelson-Van Dam-Lee mode to the compressional Alfven mode is now possible. This leads to a higher permissible core plasma beta value for stable operation.

Mortality Benefit of Recombinant Human Interleukin-1 Receptor Antagonist for Sepsis Varies by Initial Interleukin-1 Receptor Antagonist Plasma Concentration.

PubMed

Meyer, Nuala J; Reilly, John P; Anderson, Brian J; Palakshappa, Jessica A; Jones, Tiffanie K; Dunn, Thomas G; Shashaty, Michael G S; Feng, Rui; Christie, Jason D; Opal, Steven M

2018-01-01

Plasma interleukin-1 beta may influence sepsis mortality, yet recombinant human interleukin-1 receptor antagonist did not reduce mortality in randomized trials. We tested for heterogeneity in the treatment effect of recombinant human interleukin-1 receptor antagonist by baseline plasma interleukin-1 beta or interleukin-1 receptor antagonist concentration. Retrospective subgroup analysis of randomized controlled trial. Multicenter North American and European clinical trial. Five hundred twenty-nine subjects with sepsis and hypotension or hypoperfusion, representing 59% of the original trial population. Random assignment of placebo or recombinant human interleukin-1 receptor antagonist × 72 hours. We measured prerandomization plasma interleukin-1 beta and interleukin-1 receptor antagonist and tested for statistical interaction between recombinant human interleukin-1 receptor antagonist treatment and baseline plasma interleukin-1 receptor antagonist or interleukin-1 beta concentration on 28-day mortality. There was significant heterogeneity in the effect of recombinant human interleukin-1 receptor antagonist treatment by plasma interleukin-1 receptor antagonist concentration whether plasma interleukin-1 receptor antagonist was divided into deciles (interaction p = 0.046) or dichotomized (interaction p = 0.028). Interaction remained present across different predicted mortality levels. Among subjects with baseline plasma interleukin-1 receptor antagonist above 2,071 pg/mL (n = 283), recombinant human interleukin-1 receptor antagonist therapy reduced adjusted mortality from 45.4% to 34.3% (adjusted risk difference, -0.12; 95% CI, -0.23 to -0.01), p = 0.044. Mortality in subjects with plasma interleukin-1 receptor antagonist below 2,071 pg/mL was not reduced by recombinant human interleukin-1 receptor antagonist (adjusted risk difference, +0.07; 95% CI, -0.04 to +0.17), p = 0.230. Interaction between plasma interleukin-1 beta concentration and recombinant human interleukin-1 receptor antagonist treatment was not statistically significant. We report a heterogeneous effect of recombinant human interleukin-1 receptor antagonist on 28-day sepsis mortality that is potentially predictable by plasma interleukin-1 receptor antagonist in one trial. A precision clinical trial of recombinant human interleukin-1 receptor antagonist targeted to septic patients with high plasma interleukin-1 receptor antagonist may be worthy of consideration.

Improved confinement region without large magnetohydrodynamic activity in TPE-RX reversed-field pinch plasma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yambe, Kiyoyuki; Hirano, Yoichi; Sakakita, Hajime

2014-11-15

We found that spontaneous improved confinement was brought about depending on the operating region in the Toroidal Pinch Experiment-Reversed eXperiment (TPE-RX) reversed-field pinch plasma [Y. Yagi et al., Fusion Eng. Des. 45, 421 (1999)]. Gradual decay of the toroidal magnetic field at plasma surface B{sub tw} reversal makes it possible to realize a prolonged discharge, and the poloidal beta value and energy confinement time increase in the latter half of the discharge, where reversal and pinch parameters become shallow and low, respectively. In the latter half of the discharge, the plasma current and volume-averaged toroidal magnetic field 〈B{sub t}〉 increasemore » again, the electron density slowly decays, the electron temperature and soft X-ray radiation intensity increase, and the magnetic fluctuations are markedly reduced. In this period of improved confinement, the value of (〈B{sub t}〉-B{sub tw})/B{sub pw}, where B{sub pw} is the poloidal magnetic field at the plasma surface, stays almost constant, which indicates that the dynamo action occurs without large magnetohydrodynamic activities.« less

Interaction with beta-arrestin determines the difference in internalization behavor between beta1- and beta2-adrenergic receptors.

PubMed

Shiina, T; Kawasaki, A; Nagao, T; Kurose, H

2000-09-15

The beta(1)-adrenergic receptor (beta(1)AR) shows the resistance to agonist-induced internalization. As beta-arrestin is important for internalization, we examine the interaction of beta-arrestin with beta(1)AR with three different methods: intracellular trafficking of beta-arrestin, binding of in vitro translated beta-arrestin to intracellular domains of beta(1)- and beta(2)ARs, and inhibition of betaAR-stimulated adenylyl cyclase activities by beta-arrestin. The green fluorescent protein-tagged beta-arrestin 2 translocates to and stays at the plasma membrane by beta(2)AR stimulation. Although green fluorescent protein-tagged beta-arrestin 2 also translocates to the plasma membrane, it returns to the cytoplasm 10-30 min after beta(1)AR stimulation. The binding of in vitro translated beta-arrestin 1 and beta-arrestin 2 to the third intracellular loop and the carboxyl tail of beta(1)AR is lower than that of beta(2)AR. The fusion protein of beta-arrestin 1 with glutathione S-transferase inhibits the beta(1)- and beta(2)AR-stimulated adenylyl cyclase activities, although inhibition of the beta(1)AR-stimulated activity requires a higher concentration of the fusion protein than that of the beta(2)AR-stimulated activity. These results suggest that weak interaction of beta(1)AR with beta-arrestins explains the resistance to agonist-induced internalization. This is further supported by the finding that beta-arrestin can induce internalization of beta(1)AR when beta-arrestin 1 does not dissociate from beta(1)AR by fusing to the carboxyl tail of beta(1)AR.

Intermittent Anisotropic Turbulence Detected by THEMIS in the Magnetosheath

NASA Astrophysics Data System (ADS)

Macek, W. M.; Wawrzaszek, A.; Kucharuk, B.; Sibeck, D. G.

2017-12-01

Following our previous study of Time History of Events and Macroscale Interactions during Substorms (THEMIS) data, we consider intermittent turbulence in the magnetosheath depending on various conditions of the magnetized plasma behind the Earth’s bow shock and now also near the magnetopause. Namely, we look at the fluctuations of the components of the Elsässer variables in the plane perpendicular to the scale-dependent background magnetic fields and along the local average ambient magnetic fields. We have shown that Alfvén fluctuations often exhibit strong anisotropic non-gyrotropic turbulent intermittent behavior resulting in substantial deviations of the probability density functions from a normal Gaussian distribution with a large kurtosis. In particular, for very high Alfvénic Mach numbers and high plasma beta, we have clear anisotropy with non-Gaussian statistics in the transverse directions. However, along the magnetic field, the kurtosis is small and the plasma is close to equilibrium. On the other hand, intermittency becomes weaker for moderate Alfvén Mach numbers and lower values of the plasma parameter beta. It also seems that the degree of intermittency of turbulence for the outgoing fluctuations propagating relative to the ambient magnetic field is usually similar as for the ingoing fluctuations, which is in agreement with approximate equipartition of energy between these oppositely propagating Alfvén waves. We believe that the different characteristics of this intermittent anisotropic turbulent behavior in various regions of space and astrophysical plasmas can help identify nonlinear structures responsible for deviations of the plasma from equilibrium.

Improved H mode with flat central q profile on EAST

NASA Astrophysics Data System (ADS)

Liu, Haiqing; Yang, Yao; Gao, Xiang; Zeng, Long; Qian, Jinping; Gong, Xianzu; Wan, Baonian; Ding, Weixing; Brower, David Lyn; EAST Team

2017-10-01

High betaN ( 1.8) plasma with good confinement (H98y2 1.1) on EAST tokamak has been reported recently. These ELMy H-mode plasmas with Bt = 1.6T, Ip = 400 kA and q95 4.5 were heated by lower hybrid wave and neutral beam injection. The internal transport barrier (ITB) and edge transport barrier (ETB) are both observed with m/n =1/1 fishbone, which were identified to clamp central q at values close to unity. Implying an improved H-mode with flat central q profile and absence of sawteeth, like other devices. Accurate q profile, key profile for developing scenarios aim at high performance H mode, were derived by Polarimeter-interferometer (POINT) measurement as constraint. Base on the optimized current profile, better confinement (H98y2 1.4) with an electron ITB was obtained also with flat central q profile and absence of sawteeth at high betaP ( 2) regime with Bt = 2.5T, Ip = 400 kA. Both high betaN regime and high betaP regime H mode, are characterized by a stationary flat central q profile q0 >=1, but typically close to 1, absence of sawteeth, H98(y,2) >1 and simultaneously, with ITB. This work is supported by the National Magnetic Confinement Fusion Program of China with Contract No. 2014GB106002 and partly supported by the US D.O.E. contract DESC0010469.

[Associations of insulin resistance and pancreatic beta-cell function with plasma glucose level in type 2 diabetes].

PubMed

Nian, Xiaoping; Sun, Gaisheng; Dou, Chunmei; Hou, Hongbo; Fan, Xiuping; Yu, Hongmei; Ma, Ling; He, Bingxian

2002-06-10

To investigate the influence of insulin resistance and pancreatic beta-cell function on plasma glucose level in type 2 diabetes so as to provide theoretical basis for reasonable selection of hypoglycemic agents. The plasma non-specific insulin (NSINS), true insulin (TI) and glucose in eight-one type 2 diabetics, 38 males and 43 females, with a mean age of 53 years, were examined 0, 30, 60 and 120 minutes after they had 75 grams of instant noodles. The patients were divided into two groups according to their fasting plasma glucose (FPG): group A (FPG < 8.89 mmol/L) and group B (FPG> = 8.89 mmol/L). The insulin resistance was evaluated by HOMA-IR, the beta-cell function was evaluated by HOMA-beta formula and the formula deltaI(30)/deltaG(30) = (deltaI(30)-deltaI(0))/(deltaG(30)-deltaG(0)). The insulin area under curve (INSAUC) was evaluated by the formula INSAUC=FINS/2+INS(30)+INS(60)+INS(120)/2. The mean FPG was 6.23 mmol/L in group A and 12.6 mmol/L in group B. PG2H was 11.7 mmol/L in group A and 19.2 mmol/L in group B. The TI levels in group B at 0, 30, 60, 120 min during standard meal test were significantly higher than those in group A: 6.15 +/- 1.06 vs 4.77 +/- 1.06, 9.76 +/- 1.1 vs 5.88 +/- 1.1,14.68 +/- 1.11 vs 6.87 +/- 1.1 and 17.13 +/- 1.12 vs 8.0 +/- 1.1 microU/dl (all P< 0.01). The NSINS showed the same trend. The insulin resistance in group B was 1.5 times that in group A. With the insulin resistance adjusted, the beta cell function in group A was 5 to 6 times that in group B. The INSAUC in group A was 1.66 times larger than that in group B, especially the INSAUC for true insulin (2 times larger). The contribution of insulin resistance and beta cell function to PG2H was half by half in group A and 1:8 in group B. beta cell function calculated by insulin (Homa-beta) explained 41% of the plasma glucose changes in group A and 54% of the plasma glucose changes in group B. The contribution of insulin deficiency to plasma glocose was 3.3.times that of insulin resistance in group A and was 9.5 times that of insulin resistance in group B. Insulin sensitivity explained 12% of the plasma glucose changes in group A, and only 5.7% of the plasma glucose changes in group B. Diabetics with FPG greater than 8.89 mmol/L have both higher insulin resistance and poorer beta-cell function, their hyperglycemia being caused mainly by beta-cell failure, The combined use of insulin sensitizer and insulin or insulintropic agents during the initial stage of treatment is effective.

Effect of naltrexone treatment on the treadmill exercise-induced hormone release in amenorrheic women.

PubMed

Botticelli, G; Bacchi Modena, A; Bresciani, D; Villa, P; Aguzzoli, L; Florio, P; Nappi, R E; Petraglia, F; Genazzani, A R

1992-12-01

The effect of an acute physical stress on hormone secretions before and after a 10-day naltrexone treatment in untrained healthy and amenorrheic women was investigated. Plasma levels of pituitary (LH, FSH, prolactin, GH, ACTH, beta-endorphin) and adrenal (cortisol, androstenedione, testosterone) hormones were measured at rest and in response to 60 min of physical exercise. The test was done both before and after a 10-day naltrexone (50 mg/day) treatment. Graded levels of treadmill exercise (50, 70 and 90% of maximal oxygen uptake (VO2) every 20 min) was used as physical stressor. While mean +/- SE plasma LH levels in control women were higher than in amenorrheic patients and increased following the naltrexone treatment (p < 0.01), no significant differences of basal plasma hormonal levels were observed between amenorrheic and eumenorrheic women, both before and after naltrexone treatment. Physical exercise at 90% VO2 induced a significant increase in plasma GH, ACTH, beta-endorphin, cortisol, androstenedione and testosterone levels in controls before naltrexone treatment (p < 0.01). The mean increase in plasma androstenedione and testosterone levels in control women was significantly higher after naltrexone treatment (p < 0.01). In amenorrheic patients before naltrexone, physical exercise induced an increase in plasma prolactin and GH levels, but not in plasma ACTH, beta-endorphin, cortisol, testosterone and androstenedione. After naltrexone treatment, the exercise induced a significant plasma ACTH, beta-endorphin and cortisol levels, while the increase of plasma prolactin levels was significantly higher than before treatment (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Lipid peroxide, alpha-tocopherol and retinoid levels in plasma and liver of rats fed diets containing beta-carotene and 13-cis-retinoic acid.

PubMed

Alam, S Q; Alam, B S

1983-12-01

The effect of feeding large amounts of beta-carotene and 13-cis-retinoic acid (RA) on plasma and liver levels of alpha-tocopherol, lipid peroxides and retinoids was studied. Groups of young male rats were fed semipurified diets supplemented with 0, 100 mg/kg beta-carotene, 20 and 100 mg/kg 13-cis-RA. After feeding the various diets for 11 weeks, rats were killed and the concentrations of lipid peroxides, alpha-tocopherol, and retinoids were measured in blood plasma and liver. Peroxide levels were increased and alpha-tocopherol levels were decreased in plasma as well as liver of rats fed diets containing 13-cis-RA; this effect seems to be dose dependent, beta-Carotene had no significant effect on either of the above parameters. There was a decrease in the liver and plasma concentrations of retinol in rats fed 13-cis-RA; the levels of RA were generally higher in these two groups. The results suggest that the mechanism whereby 13-cis-RA increases the tissue peroxide levels may be related to its ability to decrease alpha-tocopherol levels.

Final Report: Levitated Dipole Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kesner, Jay; Mauel, Michael

2013-03-10

Since the very first experiments with the LDX, research progress was rapid and significant. Initial experiments were conducted with the high-field superconducting coil suspended by three thin rods. These experiments produced long-pulse, quasi-steady-state microwave discharges, lasting more than 10 s, having peak beta values of 20% [Garnier et al., Physics of Plasmas, 13 (2006) 056111]. High- beta, near steady-state discharges have been maintained in LDX for more than 20 seconds, and this capability made LDX the longest pulse fusion confinement experiment operating in the U.S. fusion program. A significant measure of progress in the LDX research program was the routinemore » investigation of plasma confinement with a magnetically-levitated dipole and the resulting observations of confinement improvement. In both supported and levitated configurations, detailed measurements were made of discharge evolution, plasma dynamics and instability, and the roles of gas fueling, microwave power deposition profiles, and plasma boundary shape. High-temperature plasma was created by multi frequency electron cyclotron resonance heating at 2.45 GHz, 6.4 GHz, 10.5 GHz and 28 GHz allowing control of heating profiles. Depending upon neutral fueling rates, the LDX discharges contain a fraction of energetic electrons, with mean energies above 50 keV. Depending on whether or not the superconducting dipole was levitated or supported, the peak thermal electron temperature was estimated to exceed 500 eV and peak densities to approach 1e18 m -3. We have found that levitation causes a strong inwards density pinch [Boxer et al., Nature Physics, 6 (2010) 207] and we have observed the central plasma density increase dramatically indicating a significant improvement in the confinement of a thermal plasma species.« less

An Overview of NSTX Research Facility and Recent Experimental Results

NASA Astrophysics Data System (ADS)

Ono, Masayuki

2006-10-01

The 2006 NSTX experimental campaign yielded significant new experimental results in many areas. Improved plasma control achieved the highest elongation of 2.9 and plasma shape factor q95Ip/aBT = 42 MA/m.T. Active feedback correction of error fields sustained the plasma rotation and increased the pulse length of high beta discharges. Active feedback stabilization of the resistive wall mode in high-beta, low-rotation plasmas was demonstrated for ˜100 resistive wall times. Operation at higher toroidal field showed favorable plasma confinement and HHFW heating efficiency trends with the field. A broader current profile, measured by the 12-channel MSE diagnostic in high beta discharges revealed an outward anomalous diffusivity of energetic ions due to the n=1 MHD modes. A tangential microwave scattering diagnostic measured localized electron gyro-scale fluctuations in L-mode, H-mode and reversed-shear plasmas. Evaporation of lithium onto plasma facing surfaces yielded lower density, higher temperature and improved confinement. A strong dependence of the divertor heat load and ELM behavior on the plasma triangularity was observed. Coaxial helicity injection produced a start-up current of 160 kA on closed flux surfaces.

Elevated plasma TGF-beta1 in renal diseases: cause or consequence?

PubMed

Junker, U; Haufe, C C; Nuske, K; Rebstock, K; Steiner, T; Wunderlich, H; Junker, K; Reinhold, D

2000-07-01

We previously reported elevated levels of TGF-beta1 in patients with renal carcinoma. Certain aspects led us to ask whether they might be caused by chronic damage to the kidney(s). Here we report on an extended set of patients with various renal diseases, lung cancer, humoral immunodeficiency and controls. For latent TGF-beta1 in plasma, we find that the control, immunodeficiency, lung cancer and kidney transplant groups do not differ significantly (means, 7.0-8.8 ng/ml). Also, acute short-term renal stress (extracorporal lithotrypsy) does not lead to an increase of TGF-beta1. However, the pyelonephritis patients present with levels of 19.0 ng/ml, chronic extracorporal dialysis patients with 15.5 ng/ml, and renal cell carcinoma patients with 22.8 ng/ml. For active TGF-beta1 these findings are exactly recovered. For serum levels, only the renal carcinoma group presents with significantly elevated levels of TGF-beta1. Kidney transplantation seems to normalize TGF-beta1 levels, while in the kidney cancer patients surgery has an effect only in part of the group. We conclude that elevated plasma TGF-beta1 levels are common in at least two chronic renal disease conditions, and that it normalizes with restoration of renal function. It is tempting to speculate that chronic elevation of TGF-beta1 in these patients may be critically involved in these conditions predisposing to renal cancer. Copyright 2000 Academic Press.

EVALUATION OF PLASMA SUBSTANCE P AND BETA-ENDORPHIN LEVELS IN CHILDREN WITH PRADER-WILLI SYNDROME.

PubMed

Butler, M G; Nelson, T A; Driscoll, D J; Manzardo, A M

2015-09-01

Prader-Willi syndrome (PWS) is a rare obesity-related genetic disorder often caused by a deletion of the chromosome 15q11-q13 region inherited from the father or by maternal disomy 15. Growth hormone deficiency with short stature, hypogonadism, cognitive and behavioral problems, analgesia, decreased gastric motility and decreased ability to vomit with hyperphagia are common in PWS leading to severe obesity in early childhood, if not controlled. Substance P (SP) and beta-endorphin (BE) are neuropeptides involved with centrally and peripherally mediated pain perception, emotional regulation, and gastric motility impacting nausea, emesis and feeding patterns. The goal of this study was to investigate potential mechanisms for PWS symptom development for pain, emotion and gastric motility and plasma levels of substance P and beta-endorphin between PWS and unrelated unaffected children. Plasma samples were collected from 23 Caucasian children with PWS and 18 unrelated, unaffected siblings with an average age of 8.2 ±2.0 years and age range of 5 to 11 years following an overnight fast and neuropeptide substance p and beta-endorphin levels were assessed using Multiplex sandwich immunoassays using the Luminex magnetic-bead based platform. Linear regression analysis was carried out on log-transformed values adjusted for age, sex, and body mass index (BMI). The mean plasma SP (57 ± 23 pg/ml) and BE (592 ± 200 pg/ml) levels in PWS were significantly higher than SP (35 ± 20 pg/ml, F=10.5, P <0.01) and BE (402 ± 162 pg/ml, F=10.8, P <0.01) levels found in unrelated, unaffected siblings suggesting a previously uncharacterized neuroendocrine pathophysiology in PWS. The increased BE and SP plasma levels relative to unrelated, unaffected siblings may contribute to hyperphagia, abnormal pain sensation and adrenal insufficiency seen in PWS. Increases in SP levels may be modulated by central and/or peripheral actions of BE on opioid, GABA or POMC precursors and may reflect loss of feedback inhibitory control. Further studies are needed to confirm and elucidate the biochemical basis for observed disturbances in neuropeptide levels seen in our study and may impact on the development and persistence of symptoms commonly seen in PWS.

Axisymmetric Tandem Mirrors: Stabilization and Confinement Studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Post, R.F.; Fowler, T.K.; Bulmer, R.

2005-01-15

The 'Kinetic Stabilizer' has been proposed as a means of MHD stabilizing an axisymmetric tandem mirror system. The K-S concept is based on theoretical studies by Ryutov, confirmed experimentally in the Gas Dynamic Trap experiment in Novosibirsk. In the K-S beams of ions are directed into the end of an 'expander' region outside the outer mirror of a tandem mirror. These ions, slowed, stagnated, and reflected as they move up the magnetic gradient, produce a low-density stabilizing plasma.At the Lawrence Livermore National Laboratory we have been conducting theoretical and computational studies of the K-S Tandem Mirror. These studies have employedmore » a low-beta code written especially to analyze the beam injection/stabilization process,and a new code SYMTRAN (by Hua and Fowler)that solves the coupled radial and axial particle and energy transport in a K-S T-M. Also, a 'legacy' MHD stability code, FLORA, has been upgraded and employed to benchmark the injection/stabilization code and to extend its results to high beta values.The FLORA code studies so far have confirmed the effectiveness of the K-S in stabilizing high-beta (40%) plasmas with stabilizer plasmas the peak pressures of which are several orders of magnitude smaller than those of the confined plasma.Also the SYMTRAN code has shown D-T plasma ignition from alpha particle energy deposition in T-M regimes with strong end plugging.Our studies have confirmed the viability of the K-S T-M concept with respect to MHD stability and radial and axial confinement. We are continuing these studies in order to optimize the parameters and to examine means for the stabilization of possible residual instability modes, such as drift modes and 'trapped-particle' modes. These modes may in principle be controlled by tailoring the stabilizer plasma distribution and/or the radial potential distribution.In the paper the results to date of our studies are summarized and projected to scope out possible fusion-power versions of the K-S T-M.« less

Axisymmetric Tandem Mirrors: Stabilization and Confinement Studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Post, R F; Fowler, T K; Bulmer, R

2004-07-15

The 'Kinetic Stabilizer' has been proposed as a means of MHD stabilizing an axisymmetric tandem mirror system. The K-S concept is based on theoretical studies by Ryutov, confirmed experimentally in the Gas Dynamic Trap experiment in Novosibirsk. In the K-S beams of ions are directed into the end of an 'expander' region outside the outer mirror of a tandem mirror. These ions, slowed, stagnated, and reflected as they move up the magnetic gradient, produce a low-density stabilizing plasma. At the Lawrence Livermore National Laboratory we have been conducting theoretical and computational studies of the K-S Tandem Mirror. These studies havemore » employed a low-beta code written especially to analyze the beam injection/stabilization process, and a new code SYMTRAN (by Hua and Fowler) that solves the coupled radial and axial particle and energy transport in a K-S TM. Also, a 'legacy' MHD stability code, FLORA, has been upgraded and employed to benchmark the injection/stabilization code and to extend its results to high beta values. The FLORA code studies so far have confirmed the effectiveness of the K-S in stabilizing high-beta (40%) plasmas with stabilizer plasmas the peak pressures of which are several orders of magnitude smaller than those of the confined plasma. Also the SYMTRAN code has shown D-T plasma ignition from alpha particle energy deposition in T-M regimes with strong end plugging. Our studies have confirmed the viability of the K-S-T-M concept with respect to MHD stability and radial and axial confinement. We are continuing these studies in order to optimize the parameters and to examine means for the stabilization of possible residual instability modes, such as drift modes and 'trapped-particle' modes. These modes may in principle be controlled by tailoring the stabilizer plasma distribution and/or the radial potential distribution. In the paper the results to date of our studies are summarized and projected to scope out possible fusion-power versions of the K-S T-M« less

Hormones and endocrine disruptors in human seminal plasma.

PubMed

Hampl, R; Kubatova, J; Heracek, J; Sobotka, V; Starka, L

2013-07-01

Seminal plasma represents a unique environment for maturation, nutrition, and protection of male germ cells from damaging agents. It contains an array of organic as well as inorganic chemicals, encompassing a number of biologically and immunologically active compounds, including hormones. Seminal plasma contains also various pollutants transferred from outer environment known as endocrine disruptors. They interfere with hormones at the receptor level, act as inhibitors of their biosynthesis, and affect hormone regulation.In this minireview, the main groups of hormones detected in seminal plasma are summarized. Seminal gonadal steroids were investigated mostly with aim to use them as biomarkers of impaired spermatogenesis (sperm count, motility, morphology). Concentrations of hormones in the seminal plasma often differ considerably from the blood plasma levels in dependence on their origin. In some instances (dihydrotestosterone, estradiol), their informative value is higher than determination in blood.Out of peptide hormones detected in seminal plasma, peptides of transforming growth factor beta family, especially antimullerian hormone, and oligopeptides related to thyrotropin releasing hormone have the high informative value, while assessment of seminal gonadotropins and prolactin does not bring advantage over determination in blood.Though there is a large body of information about the endocrine disruptors' impact on male reproduction, especially with their potential role in decline of male reproductive functions within the last decades, there are only scarce reports on their presence in seminal plasma. Herein, the main groups of endocrine disruptors found in seminal plasma are reviewed, and the use of their determination for investigation of fertility disorders is discussed.

Effect of citric pectin on beta-carotene bioavailability in rats.

PubMed

Zanutto, Márcia E; Jordão Júnior, Alceu A; Meirelles, Mônica S S; Fávaro, Rosa M D; Vannucchi, Hélio

2002-07-01

The effect of citric pectin on the bioavailability of synthetic beta-carotene was studied. Thirty Wistar rats were used, ten animals were sacrificed at the beginning of the experiment and remaining animals were divided into two groups and received the following diets for 30 days: control group (CG)--24 micrograms beta-carotene/g diet + 0% citric pectin; experimental group (EG)--24 micrograms beta-carotene/g diet + 7% citric pectin. Plasma and liver beta-carotene, vitamin A, and retinyl palmitate concentrations were determined by high-performance liquid chromatography (HPLC). Plasma retinol concentration was 1.42 +/- 0.36 mumol/L for CG and 1.10 +/- 0.24 mumol/L for EG (p = 0.1), and plasma beta-carotene concentration was 0.20 +/- 2.51 mumol/L for CG and 0.07 +/- 0.04 mumol/L for EG (p = 0.01). Only traces of retinyl palmitate were detected in CG and none in EG. Retinol did not differ significantly between groups CG and EG, while a significantly higher beta-carotene concentration was observed for CG. Liver concentrations of retinol (CG: 4.90 +/- 2.51 micrograms/g; EG: 2.68 +/- 1.12 micrograms/g), beta-carotene (CG: 0.98 +/- 0.28 microgram/g; EG: 0.11 +/- 0.06 microgram/g), and retinyl palmitate (CG: 95.47 +/- 45.13 micrograms/g, EG: 37.01 +/- 17.20 micrograms/g) differed significantly between groups (p < 0.05), with a lower concentration being observed for EG. We conclude that 7% citric pectin in the rat diet decreases the bioavailability of synthetic beta-carotene, reducing the liver reserves of vitamin A and beta-carotene.

Glucose recruits K(ATP) channels via non-insulin-containing dense-core granules.

PubMed

Yang, Shao-Nian; Wenna, Nancy Dekki; Yu, Jia; Yang, Guang; Qiu, Hua; Yu, Lina; Juntti-Berggren, Lisa; Köhler, Martin; Berggren, Per-Olof

2007-09-01

beta cells rely on adenosine triphosphate-sensitive potassium (K(ATP)) channels to initiate and end glucose-stimulated insulin secretion through changes in membrane potential. These channels may also act as a constituent of the exocytotic machinery to mediate insulin release independent of their electrical function. However, the molecular mechanisms whereby the beta cell plasma membrane maintains an appropriate number of K(ATP) channels are not known. We now show that glucose increases K(ATP) current amplitude by increasing the number of K(ATP) channels in the beta cell plasma membrane. The effect was blocked by inhibition of protein kinase A (PKA) as well as by depletion of extracellular or intracellular Ca(2+). Furthermore, glucose promoted recruitment of the potassium inward rectifier 6.2 to the plasma membrane, and intracellular K(ATP) channels localized in chromogranin-positive/insulin-negative dense-core granules. Our data suggest that glucose can recruit K(ATP) channels to the beta cell plasma membrane via non-insulin-containing dense-core granules in a Ca(2+)- and PKA-dependent manner.

Reduction of Plasma Globotriaosylsphingosine Levels After Switching from Agalsidase Alfa to Agalsidase Beta as Enzyme Replacement Therapy for Fabry Disease.

PubMed

Goker-Alpan, Ozlem; Gambello, Michael J; Maegawa, Gustavo H B; Nedd, Khan J; Gruskin, Daniel J; Blankstein, Larry; Weinreb, Neal J

2016-01-01

Agalsidase alfa and agalsidase beta, recombinant enzyme preparations for treatment of Fabry disease (FD), have different approved dosing schedules: 0.2 mg/kg and 1.0 mg/kg every other week (EOW), respectively. This open-label, multicenter, exploratory phase 4 study evaluated plasma globotriaosylsphingosine (lyso-GL-3) and plasma and urine globotriaosylceramide (GL-3) levels at baseline and 2, 4, and 6 months after the switch from agalsidase alfa (0.2 mg/kg EOW for ≥12 months) to agalsidase beta (1.0 mg/kg EOW) in 15 male patients with FD. Immunoglobulin (Ig)G antidrug antibody titers were assessed, and safety was monitored throughout the study. Plasma lyso-GL-3 concentrations decreased significantly within 2 months after switch and reductions continued through month 6 (mean absolute changes, -12.8, -16.1, and -16.7 ng/mL at 2, 4, and 6 months, respectively; all P < 0.001). The mean percentage reduction from baseline was 39.5% (P < 0.001) at month 6. For plasma GL-3, the mean absolute change from baseline (-0.9 μg/mL) and percentage reduction (17.9%) at month 6 were both significant (P < 0.05). Urine GL-3 measurements showed intra-patient variability and changes from baseline were not significant. No clinical outcomes were assessed in this 6-month study, and, therefore, no conclusions can be drawn regarding the correlation of observed reductions in glycosphingolipid concentrations with clinically relevant outcomes. There were no differences in IgG antidrug antibody titers between the two enzymes. The switch from agalsidase alfa to agalsidase beta was well tolerated. Plasma lyso-GL-3 and GL-3 levels reduced after switching from agalsidase alfa to agalsidase beta, indicating that agalsidase beta has a greater pharmacodynamic effect on these markers at the recommended dose. These data further support the use of agalsidase beta 1.0 mg/kg EOW as enzyme replacement therapy in FD.

A single-dose pharmacokinetic study of emamectin benzoate in cod, Gadus morhua L., held in sea water at 9 degrees C.

PubMed

Samuelsen, O B

2010-02-01

The pharmacokinetic profile of the antiparasitic agent emamectin benzoate was studied in plasma after intravenous (i.v.) injection and in plasma, muscle and skin following oral (p.o.) administration to cod, Gadus morhua, held in sea water at 9 degrees C and weighing 100-200 g. Following i.v. injection, the plasma drug concentration-time profile showed two distinct phases. The plasma distribution half-life (t(1/2)alpha) was estimated as 2.5 h, the elimination half-life (t(1/2)beta) as 216 h, the total body clearance (Cl(T)) as 0.0059 L kg(-1) h(-1) and mean residence time (MRT) as 385 h. The volume of distribution at steady state, V(d(ss)), was calculated to be 1.839 L kg(-1). Following p.o. administration the peak plasma concentration (C(max)) was 15 ng mL(-1), the time to peak plasma concentration (T(max)) was 89 h and t(1/2)beta was 180 h. The highest concentration in muscle (21 ng g(-1)) was measured after 7 days and t(1/2)beta was calculated to be 247 h. For skin, a peak concentration of 28 ng g(-1) at 3 days was observed and a t(1/2)beta of 235 h was determined. The bioavailability following p.o. administration was calculated to be 38%.

Hepatic apoptotic activity following transient normothermic inflow occlusion and reperfusion in the swine model.

PubMed

Helling, T S; Edwards, C A; Helling, T S; Chang, C C; Hodges, M C; Dhar, A; VanWay, C

1999-09-01

Accelerated hepatic apoptosis was first described in portal vein-ligated livers but has since been reported in a variety of liver injuries. Because porto-prival states can induce apoptosis we sought to determine whether transient ischemic periods followed by reperfusion would trigger such cell death. The cytokines TNF-alpha and TGF-beta are known to facilitate apoptosis and are released in response to a number of stimuli including ischemia. We also investigated alterations in plasma and tissue levels of these cytokines which might lend support to their role in increased apoptotic activity following ischemia/reperfusion. Female pigs were used as the experimental model. Inflow occlusion of portal and hepatic arterial blood was performed to a portion of the swine liver directing the entire splanchnic flow to the remaining hepatic lobes for a period of 2 h. The livers were then reperfused and plasma and tissue samples taken for determination of apoptotic activity utilizing cell death immunoperoxidase staining of 3'-OH DNA ends generated by fragmentation and ELISA assay of histone-associated DNA fragments. Plasma and tissue levels of TNF-alpha and plasma levels of TGF-beta were determined by ELISA assay. An increase in apoptotic activity following reperfusion was seen at Day 2 and Day 4 compared to preischemic values by the cell death stain. The ELISA cell death assay showed an increase in apoptotic activity at 60 min, Day 2, and Day 4. Moreover, the ELISA cell death assay showed enhanced apoptotic activity in "hyperperfused" hepatic lobes compared to preischemic, or resting, liver. This was also observed when compared to sham-operated animals. Surprisingly, there was no detectable increase in plasma TNF-alpha or TGF-beta levels following ischemia/reperfusion, although homogenized liver TNF-alpha levels were increased at 60 min and Day 2 following reperfusion. We conclude that transient hepatic inflow occlusion followed by reperfusion can induce increased apoptotic activity in the swine model. Furthermore, increased apoptotic activity also occurs in the hyperperfused liver raising the possibility of a locally active factor or global hepatic expression of receptor activity in response to ischemia/reperfusion. This period of ischemia/reperfusion did not produce a detectable increase in circulating cytokine levels, and accelerated apoptosis could not be linked to heightened TNF-alpha or TGF-beta plasma activity. Higher tissue levels of TNF-alpha could reflect enhanced binding to TNF cell surface receptors or amplified receptor expression. Copyright 1999 Academic Press.

Perturbative momentum transport in MAST L-mode plasmas

DOE PAGES

Guttenfelder, W.; Field, A. R.; Lupelli, I.; ...

2017-03-28

Non-axisymmetric magnetic fields are used to perturbatively probe momentum transport physics in MAST L-mode plasmas. The low beta L-mode target was chosen to complement previous experiments conducted in high beta NSTX H-mode plasmas (beta N = 3.5-4.6) where an inward momentum pinch was measured. In those cases quasi-linear gyrokinetic simulations of unstable ballooning micro-instabilities predict weak or outward momentum convection, in contrast to the measurements. The weak pinch was predicted to be due to both electromagnetic effects at high beta and low aspect ratio minimizing the symmetry-breaking of the instabilities responsible for momentum transport. In an attempt to lessen thesemore » electromagnetic effects at low aspect ratio, perturbative experiments were run in MAST L-mode discharges at lower beta (beta N = 2). The perturbative transport analysis used the time-dependent response following the termination of applied 3D fields that briefly brake the plasma rotation ( similar to the NSTX H-mode experiments). Assuming time-invariant diffusive (chi(phi))and convective (V-phi) transport coefficients, an inward pinch is inferred with magnitudes, (RV phi/chi(phi)) = (-1)-(-9), similar to those found in NSTX H-modes and in conventional tokamaks. However, if experimental uncertainties due to non-stationary conditions during and after the applied 3D field are considered, a weak pinch or even outward convection is inferred, ( RV phi/chi(phi)) = (-1)-(+5). Linear gyrokinetic simulations indicate that for these lower beta L-modes, the predicted momentum pinch is predicted to be relatively small, ( RV phi/chi(phi))(sim) approximate to -1. While this falls within the experimentally inferred range, the uncertainties are practically too large to quantitatively validate the predictions. Challenges and implications for this particular experimental technique are discussed, as well as additional possible physical mechanisms that may be important in understanding momentum transport in these low aspect ratio plasmas.« less

Perturbative momentum transport in MAST L-mode plasmas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guttenfelder, W.; Field, A. R.; Lupelli, I.

Non-axisymmetric magnetic fields are used to perturbatively probe momentum transport physics in MAST L-mode plasmas. The low beta L-mode target was chosen to complement previous experiments conducted in high beta NSTX H-mode plasmas (beta N = 3.5-4.6) where an inward momentum pinch was measured. In those cases quasi-linear gyrokinetic simulations of unstable ballooning micro-instabilities predict weak or outward momentum convection, in contrast to the measurements. The weak pinch was predicted to be due to both electromagnetic effects at high beta and low aspect ratio minimizing the symmetry-breaking of the instabilities responsible for momentum transport. In an attempt to lessen thesemore » electromagnetic effects at low aspect ratio, perturbative experiments were run in MAST L-mode discharges at lower beta (beta N = 2). The perturbative transport analysis used the time-dependent response following the termination of applied 3D fields that briefly brake the plasma rotation ( similar to the NSTX H-mode experiments). Assuming time-invariant diffusive (chi(phi))and convective (V-phi) transport coefficients, an inward pinch is inferred with magnitudes, (RV phi/chi(phi)) = (-1)-(-9), similar to those found in NSTX H-modes and in conventional tokamaks. However, if experimental uncertainties due to non-stationary conditions during and after the applied 3D field are considered, a weak pinch or even outward convection is inferred, ( RV phi/chi(phi)) = (-1)-(+5). Linear gyrokinetic simulations indicate that for these lower beta L-modes, the predicted momentum pinch is predicted to be relatively small, ( RV phi/chi(phi))(sim) approximate to -1. While this falls within the experimentally inferred range, the uncertainties are practically too large to quantitatively validate the predictions. Challenges and implications for this particular experimental technique are discussed, as well as additional possible physical mechanisms that may be important in understanding momentum transport in these low aspect ratio plasmas.« less

A table top experiment to investigate production and properties of a plasma confined by a dipole magnet

NASA Astrophysics Data System (ADS)

Baitha, Anuj Ram; Kumar, Ashwani; Bhattacharjee, Sudeep

2018-02-01

We report a table top experiment to investigate production and properties of a plasma confined by a dipole magnet. A water cooled, strong, cylindrical permanent magnet (NdFeB) magnetized along the axial direction and having a surface magnetic field of ˜0.5 T is employed to create a dipole magnetic field. The plasma is created by electron cyclotron resonance heating. Visual observations of the plasma indicate that radiation belts appear due to trapped particles, similar to the earth's magnetosphere. The electron temperature lies in the range 2-13 eV and is hotter near the magnets and in a downstream region. It is found that the plasma (ion) density reaches a value close to 2 × 1011 cm-3 and peaks at a radial distance about 3 cm from the magnet. The plasma beta β (β = plasma pressure/magnetic pressure) increases radially outward, and the maximum β for the present experimental system is ˜2%. It is also found that the singly charged ions are dominant in the discharge.

Retinoid metabolism and transplacental pharmacokinetics in the cynomolgus monkey following a nonteratogenic dosing regimen with all-trans-retinoic acid.

PubMed

Tzimas, G; Nau, H; Hendrickx, A G; Peterson, P E; Hummler, H

1996-11-01

Retinoids often exhibit a complex metabolic pattern and differential transplacental kinetics, which make it difficult to pinpoint the proximate compound responsible for the observed teratogenic effect. We have therefore studied the pharmacokinetics and metabolism of all-trans-retinoic acid (all-trans-RA) in cynomolgus monkeys following application of a nonteratogenic dosing regimen and compared the results with corresponding data from a previous study with a teratogenic dosing regimen with 13-cis-RA [Hummler et al. (1994) Teratology 50:184-193]. All-trans-RA was administered to pregnant cynomolgus monkeys (Macaca fascicularis) by nasogastric intubation at a dose of 5 mg/kg body wt once daily from gestational day (GD) 16 to 26 and twice daily at 8-h intervals from GD 27 to 31. Examination of the fetuses of four dams on GD 100 +/- 2 showed no embryotoxic or teratogenic effects of the applied dosing regimen (Experiment 1). Maternal plasma retinoid pharmacokinetics on GD 16, 26, and 31 as well as embryonic retinoid profiles after the last drug administration on GD 31 were determined in thirteen further dams (Experiment 2). All-trans-RA reached much lower plasma concentrations after the last two treatments on GD 31 than after the first one on GD 16 and the eleventh one on GD 26 (0-24-h area-under-the-concentration-time-curve (AUC) values: 104 +/- 59 ng x h/ml (after the last treatment on GD 31), 189 +/- 110 (GD 16) and 393 +/- 305 ng x h/ml (GD 26). The predominant plasma metabolites of all-trans-RA were its beta-glucuronide and the beta-glucuronide of all-trans-4-oxo-RA. Both of these retinoids accumulated in the plasma during the period of treatment and displayed AUC values 5- to 30-fold higher than those of all-trans-RA. Embryonic concentrations of all-trans-RA were not increased over endogenous levels after the last administration on GD 31 when plasma concentrations were low. To evaluate the placental transport of all-trans-RA in the presence of high plasma concentrations, a further experiment was performed, in which a single dose of all-trans-RA (10 mg/kg body wt) was given to four pregnant monkeys on GD 31, and plasma pharmacokinetics as well as embryonic concentrations of retinoids at 4 h post-treatment were determined (Experiment 3). This dosing schedule yielded high plasma concentrations of all-trans-RA, while embryonic concentrations were about 40% of plasma levels. Based on the plasma AUC values on GDs 16 and 26 obtained in Experiment 2 and the degree of placental transfer, as determined on GD 31 in the presence of high plasma levels in Experiment 3, we estimated embryonic AUC values for the 24-h period following the nonteratogenic doses on GDs 16 and 26 in Experiment 2. These AUC values were similarly high to the embryonic AUC value of all-trans-RA obtained after application of the teratogenic dosing regimen with 13-cis-RA [Hummler et al. (1994) Teratology 50:184-193]. In addition, plasma AUC values of all-trans-RA were 2- to 7-fold higher after all-trans-RA administration (present study) than after dosing with the teratogenic dose of 13-cis-RA. These results strengthen our recent suggestion that the teratogenic effects induced in cynomolgus monkeys by 13-cis-RA treatment cannot solely result from the action of all-trans-RA, but may involve 13-cis-RA and 13-cis-4-oxo-RA, which could act directly or function as transport vehicle.

Pathogenesis of A-beta+ ketosis-prone diabetes

USDA-ARS?s Scientific Manuscript database

A-beta+ ketosis-prone diabetes (KPD) is an emerging syndrome of obesity, unprovoked ketoacidosis, reversible beta-cell dysfunction, and near-normoglycemic remission. We combined metabolomics with targeted kinetic measurements to investigate its pathophysiology. Fasting plasma fatty acids, acylcarnit...

Study of the confinement properties in a reversed-field pinch with mode rotation and gas fuelling

NASA Astrophysics Data System (ADS)

Cecconello, M.; Malmberg, J.-A.; Nielsen, P.; Pasqualotto, R.; Drake, J. R.

2002-08-01

An extensive investigation of the global confinement properties in different operating scenarios in the rebuilt EXTRAP T2R reversed-field pinch (RFP) experiment is reported here. In particular, the role of a fast gas puff valve system, used to control plasma density, on confinement is studied. Without gas puffing, the electron density decays below 0.5×1019 m-3. The poloidal beta varies between 5% and 15%, decreasing at large I/N. The energy confinement time ranges from 70 to 225 μs. With gas puffing, the density is sustained at ne≈1.5×1019 m-3. However, a general slight deterioration of the plasma performances is observed for the same values of I/N: the plasma becomes cooler and more radiative. The poloidal beta is comparable to that in the scenarios without puff but the energy confinement time drops ranging from 60 to 130 μs. The fluctuation level and the energy confinement time have been found to scale with the Lundquist number as S-0.05+/-0.07 and S0.5+/-0.1, respectively. Mode rotation is typical for all the discharges and rotation velocity is observed to increase with increasing electron diamagnetic velocity.

Metabolic profiling of PPARalpha-/- mice reveals defects in carnitine and amino acid homeostasis that are partially reversed by oral carnitine supplementation.

PubMed

Makowski, Liza; Noland, Robert C; Koves, Timothy R; Xing, Weibing; Ilkayeva, Olga R; Muehlbauer, Michael J; Stevens, Robert D; Muoio, Deborah M

2009-02-01

Peroxisome proliferator-activated receptor-alpha (PPARalpha) is a master transcriptional regulator of beta-oxidation and a prominent target of hypolipidemic drugs. To gain deeper insights into the systemic consequences of impaired fat catabolism, we used quantitative, mass spectrometry-based metabolic profiling to investigate the fed-to-fasted transition in PPARalpha(+/+) and PPARalpha(-/-) mice. Compared to PPARalpha(+/+) animals, acylcarnitine profiles of PPARalpha(-/-) mice revealed 2- to 4-fold accumulation of long-chain species in the plasma, whereas short-chain species were reduced by as much as 69% in plasma, liver, and skeletal muscle. These results reflect a metabolic bottleneck downstream of carnitine palmitoyltransferase-1, a mitochondrial enzyme that catalyzes the first step in beta-oxidation. Organic and amino acid profiles of starved PPARalpha(-/-) mice suggested compromised citric acid cycle flux, enhanced urea cycle activity, and increased amino acid catabolism. PPARalpha(-/-) mice had 40-50% lower plasma and tissue levels of free carnitine, corresponding with diminished hepatic expression of genes involved in carnitine biosynthesis and transport. One week of oral carnitine supplementation conferred partial metabolic recovery in the PPARalpha(-/-) mice. In summary, comprehensive metabolic profiling revealed novel biomarkers of defective fat oxidation, while also highlighting the potential value of supplemental carnitine as a therapy and diagnostic tool for metabolic disorders.

A critical shock mach number for particle acceleration in the absence of pre-existing cosmic rays: M=√5

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vink, Jacco; Yamazaki, Ryo, E-mail: j.vink@uva.nl

2014-01-10

It is shown that, under some generic assumptions, shocks cannot accelerate particles unless the overall shock Mach number exceeds a critical value M>√5. The reason is that for M≤√5 the work done to compress the flow in a particle precursor requires more enthalpy flux than the system can sustain. This lower limit applies to situations without significant magnetic field pressure. In case that the magnetic field pressure dominates the pressure in the unshocked medium, i.e., for low plasma beta, the resistivity of the magnetic field makes it even more difficult to fulfill the energetic requirements for the formation of shockmore » with an accelerated particle precursor and associated compression of the upstream plasma. We illustrate the effects of magnetic fields for the extreme situation of a purely perpendicular magnetic field configuration with plasma beta β = 0, which gives a minimum Mach number of M = 5/2. The situation becomes more complex, if we incorporate the effects of pre-existing cosmic rays, indicating that the additional degree of freedom allows for less strict Mach number limits on acceleration. We discuss the implications of this result for low Mach number shock acceleration as found in solar system shocks, and shocks in clusters of galaxies.« less

Beta electron fluxes inside a magnetic plasma cavern: Calculation and comparison with experiment

NASA Astrophysics Data System (ADS)

Stupitskii, E. L.; Smirnov, E. V.; Kulikova, N. A.

2010-12-01

We study the possibility of electrostatic blanking of beta electrons in the expanding spherical blob of a radioactive plasma in a rarefied ionosphere. From numerical studies on the dynamics of beta electrons departing a cavern, we obtain the form of a function that determines the portion of departing electrons and calculate the flux density of beta electrons inside the cavern in relation to the Starfish Prime nuclear blast. We show that the flux density of electrons in geomagnetic flux tubes and inside the cavern depend on a correct allowance for the quantity of beta electrons returning to the cavern. On the basis of a physical analysis, we determine the approximate criterion for the return of electrons from a geomagnetic flux tube to the cavern. We compare calculation results in terms of the flux density of beta electrons inside the cavern with the recently published experimental results from operation Starfish Prime.

Dietary and hormonal interrelationships among vegetarian Seventh-Day Adventists and nonvegetarian men.

PubMed

Howie, B J; Shultz, T D

1985-07-01

The relationship between dietary nutrients and plasma testosterone, 5 alpha-dihydrotestosterone, estradiol-17 beta, luteinizing hormone, and prolactin levels was investigated in 12 Seventh-Day Adventist (SDA) vegetarian (SV), 10 SDA nonvegetarian (SNV), and 8 non-SDA nonvegetarian (NV) men. Fasting blood samples and 3-day dietary intake information were obtained from each subject. The SV subjects consumed significantly more crude and dietary fiber than the SNV and NV subjects, respectively. Plasma levels of testosterone and estradiol-17 beta were significantly lower in the SV than in the omnivores. Additionally, the plasma levels of testosterone and estradiol-17 beta of the combined groups (SV, SNV, and NV) revealed a significant negative relationship with their crude and dietary fiber intakes. These subjects hormonal milieu was related to specific dietary constituents, possibly leading to a decreased plasma concentration of androgen and estrogen in vegetarians. Implications include the possible modification of prostate cancer risk through dietary intervention.

von Kármán–Howarth Equation for Hall Magnetohydrodynamics: Hybrid Simulations

NASA Astrophysics Data System (ADS)

Hellinger, Petr; Verdini, Andrea; Landi, Simone; Franci, Luca; Matteini, Lorenzo

2018-04-01

A dynamical vectorial equation for homogeneous incompressible Hall-magnetohydrodynamic (MHD) turbulence together with the exact scaling law for third-order correlation tensors, analogous to that for the incompressible MHD, is rederived and applied to the results of two-dimensional hybrid simulations of plasma turbulence. At large (MHD) scales the simulations exhibit a clear inertial range where the MHD dynamic law is valid. In the sub-ion range the cascade continues via the Hall term, but the dynamic law derived in the framework of incompressible Hall-MHD equations is obtained only in a low plasma beta simulation. For a higher beta plasma the cascade rate decreases in the sub-ion range and the change becomes more pronounced as the plasma beta increases. This break in the cascade flux can be ascribed to nonthermal (kinetic) features or to others terms in the dynamical equation that are not included in the Hall-MHD incompressible approximation.

On the ordinary mode instability for low beta plasmas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hadi, F.; Qamar, A.; Bashir, M. F.

2014-05-15

The purely growing ordinary (O) mode instability, first discussed by Davidson and Wu [Phys. Fluids 13, 1407 (1970)], has recently received renewed attention owing to its potential applicability to the solar wind plasma. In a series of papers, Ibscher, Schlickeiser, and their colleagues [Phys. Plasmas 19, 072116 (2012); ibid. 20, 012103 (2013); ibid. 20, 042121 (2013); ibid. 21, 022110 (2014)] revisited the O mode instability and extended it to the low-beta plasma regime by considering a counter-streaming bi-Maxwellian model. However, the O-mode instability is, thus, far discussed only on the basis of the marginal stability condition rather than actual numericalmore » solutions of the dispersion relation. The present paper revisits the O-mode instability by considering the actual complex roots. The marginal stability condition as a function of the (electron) temperature anisotropy and beta naturally emerges in such a scheme.« less

Serum tryptase level is a better predictor of systemic side effects than prostaglandin D2 metabolites during venom immunotherapy in children.

PubMed

Cichocka-Jarosz, E; Sanak, M; Szczeklik, A; Brzyski, P; Gielicz, A; Pietrzyk, J J

2011-01-01

We performed a prospective study to analyze mast cell mediators as predictors of systemic adverse reactions during rush venom-specific immunotherapy (VIT) in children. Nineteen children aged 5-17 years received VIT with Venomenhal (HALAllergy). We analyzed serum tryptase (CAP, Phadia), plasma prostaglandin (PG) D2 metabolites (9alpha, 11beta-PGF2), and urine PGD2 metabolites (9alpha, 11beta-PGF2, tetranor-PGD-M) using gas chromatography mass spectrometry before and after the rush protocol. Three boys with high baseline serum tryptase values (>7.76 g/L) (P < .001) and low 9alpha, 11beta-PGF2 concentrations developed grade III systemic adverse reactions during VIT. Baseline serum tryptase was lowest in children who had a Mueller grade II reaction (1.93 [0.36]) before VIT and highest in children with a Mueller grade III reaction (6.31 [4.80]) (P = .029). Repeated measures analysis of variance confirmed that, in children who developed systemic adverse reactions during VIT, serum tryptase was higher both before and after desensitization and increased significantly following the procedure. Analysis of PGD2 metabolites in the prediction of systemic adverse reactions during VIT was inadequate (sensitivity 67% and specificity 0.53%), whilst prediction based on serum tryptase was accurate. In children with severe systemic adverse reactions to Hymenoptera sting, the evaluation of baseline tryptase levels should be a standard procedure. Children with Apis mellifera venom allergy and baseline tryptase levels higher than 7.75 g/L are at risk of anaphylaxis during buildup. Lower baseline values of plasma and urinary PGD2 metabolite concentration in patients with systemic adverse reaction during VIT suggest that prostaglandin catabolism is altered.

Arginine supplementation of sickle transgenic mice reduces red cell density and Gardos channel activity.

PubMed

Romero, José R; Suzuka, Sandra M; Nagel, Ronald L; Fabry, Mary E

2002-02-15

Nitric oxide (NO), essential for maintaining vascular tone, is produced from arginine by nitric oxide synthase. Plasma arginine levels are low in sickle cell anemia, and it is reported here that low plasma arginine is also found in our sickle transgenic mouse model that expresses human alpha, human beta(S), and human beta(S-Antilles) and is homozygous for the mouse beta(major) deletion (S+S-Antilles). S+S-Antilles mice were supplemented with a 4-fold increase in arginine that was maintained for several months. Mean corpuscular hemoglobin concentration (MCHC) decreased and the percent high-density red cells was reduced. Deoxy K(+) efflux is characteristic of red cells in sickle cell disease and contributes to the disease process by increasing the MCHC and rendering the cells more susceptible to polymer formation. This flux versus the room air flux was reduced in S+S-Antilles red cells from an average value of 1.6 +/- 0.3 mmol per liter of red cells x minute (FU) in nonsupplemented mice to 0.9 +/- 0.3 FU (n = 4, P < .02, paired t test) in supplemented mice. In room air, V(max) of the Ca(++)-activated K(+) channel (Gardos) was reduced from 4.1 +/- 0.6 FU (off diet) to 2.6 +/- 0.4 FU (n = 7 and 8, P < .04, t test) in arginine-supplemented mice versus clotrimazole. In conclusion, the major mechanism by which arginine supplementation reduces red cell density (MCHC) in S+S-Antilles mice is by inhibiting the Ca(++)-activated K(+) channel.

First Trial of Real-time Poloidal Beta Control in KSTAR

NASA Astrophysics Data System (ADS)

Han, Hyunsun; Hahn, S. H.; Bak, J. G.; Walker, M. L.; Woo, M. H.; Kim, J. S.; Kim, Y. J.; Bae, Y. S.; KSTAR Team

2014-10-01

Sustaining the plasma in a stable and a high performance condition is one of the important control issues for future steady state tokamaks. In the 2014 KSTAR campaign, we have developed a real-time poloidal beta (βp) control technique and carried out preliminary experiments to identify its feasibility. In the control system, the βp is calculated in real time using the measured diamagnetic loop signal (DLM03) with coil pickup corrections, and compared with the target value leading to the change of the neutral beam (NB) heating power using a feedback PID control algorithm. To match the required power of NB which is operated with constant voltage, the duty cycles of the modulation were adjusted as the ratio of the required power to the maximum achievable one. This paper will present the overall procedures of the βp control, the βp estimation process implemented in the plasma control system, and the analysis on the preliminary experimental results. This work is supported by the KSTAR research project funded by the Ministry of Science, ICT & Future Planning of Korea.

Numerical simulation of the multiple core localized low shear toroidal Alfvenic eigenmodes

NASA Astrophysics Data System (ADS)

Wang, Wenjia; Zhou, Deng; Hu, Youjun; Ming, Yue

2018-03-01

In modern tokamak experiments, scenarios with weak central magnetic shear has been proposed. It is necessary to study the Alfvenic mode activities in such scenarios. Theoretical researches have predicted the multiplicity of core-localized toroidally induced Alfvenic eigenmodes for ɛ/s > 1, where ɛ is the inverse aspect ratio and s is magnetic shear. We numerically investigate the existence of multiplicity of core-localized TAEs and mode characteristics using NOVA code in the present work. We firstly verify the existence of the multiplicity for zero beta plasma and the even mode at the forbidden zone. For finite beta plasma, the mode parities become more distinguishable, and the frequencies of odd modes are close to the upper tip of the continuum, while the frequencies of even modes are close to the lower tip of the continuum. Their frequencies are well separated by the forbidden zone. With the increasing value of ɛ/s, more modes with multiple radial nodes will appear, which is in agreement with theoretical prediction. The discrepancy between theoretical prediction and our numerical simulation is also discussed in the main text.

Neuroimmune response to endogenous and exogenous pyrogens is differently modulated by sex steroids.

PubMed

Mouihate, A; Pittman, Q J

2003-06-01

The objective of this study was to explore whether and how ovarian hormones interact with the febrile response to pyrogens. Estrogen and progesterone treatment of ovariectomized rats was associated with a reduction in lipopolysaccharide (LPS)-induced fever, compared with ovariectomized controls. LPS-fever reduction was accompanied by reduced levels of the inducible cyclooxygenase-2 (COX-2) protein expression in the hypothalamus as well as reduced plasma levels of IL-1beta. The amount of LPS-induced IL-6 in the plasma was not affected by ovarian hormone replacement. In contrast, hypothalamic COX-2 expression in response to intraperitoneal injection of IL-1beta was potentiated by the ovarian hormone replacement. IL-1beta induced a moderate increase in plasma levels of IL-6 that was suppressed by ovarian hormone replacement. These data suggest that ovarian hormone replacement attenuated the proinflammatory response to LPS by suppressing the LPS-induced IL-1beta production and COX-2 expression in the hypothalamus. The markedly different action of ovarian hormones on IL-1beta and LPS effects suggests that this sex hormone modulation of the immune response is a function of the nature of infection and provides further evidence that LPS actions are different from those of IL-1beta.

Osteoporotic cytokines and bone metabolism on rats with induced hyperthyroidism; changes as a result of reversal to euthyroidism.

PubMed

Simsek, Gönül; Karter, Yesari; Aydin, Seval; Uzun, Hafize

2003-12-31

Hyperthyroidism is characterized by increased bone turnover and resorptive activity. Raised levels of serum osteoporotic cytokines, such as interleukin (IL) -1beta, IL-6 and tumor necrosis factor (TNF)-alpha have been demonstrated previously in hyperthyroidism. These elevations are controversial and it is difficult to differentiate the contribution of thyroid hormones to the elevation of cytokines from that of the autoimmune inflammation in Graves' disease (GD) and follicular cell damage in thyroiditis. Therefore, we investigated the effect of thyroid hormones on serum IL-1beta, IL-6, TNF-alpha levels and bone metabolism on L-thyroxine induced hyperthyroid rats and changes in cytokine levels and bone metabolism on the same rats after reversal to euthyroidism. Rats were treated with L-thyroxine for 5 weeks (0.4 mg/ 100 g food). Plasma T3, T4, TSH and serum IL-1beta, IL-6, TNFalpha, Calcium (Ca), phosphorous (P), parathyroid hormone (PTH), alkaline phosphatase (ALP), bone alkaline phosphatase (B-ALP) levels were measured and differential leucocyte counts were made initially, at the 5th week of the experiment (hyperthyroid state) and 5 weeks after quitting the administration of L-thyroxine (euthyroid state). Significant rises in serum IL-1beta, IL-6 and TNFalpha were noted in hyperthyroidism (P < 0.001). In euthyroid state, IL-15, IL-6 and TNFalpha decreased significantly, but IL-beta and TNFalpha were significantly higher than the baseline values (P < 0.05) while IL-6 levels turned back to the baseline values. Plasma T3 and T4 levels were significantly correlated with serum cytokines in hyperthyroid state while there was no correlation in euthyroid states. Ca and P levels did not differ significantly while PTH levels declined significantly in the hyperthyroid state (P < 0.05). After the reversal to the euthyroidism, there was no significant change in Ca, P and PTH levels. ALP and B-ALP increased significantly in hyperthyroidism (P < 0.001, P < 0.01) and they did not decrease in euthyroid state. The lymphocyte number and ratio in differentials increased significantly in the hyperthyroid state (P < 0.001). In euthyroidism they decreased significantly (P < 0.001) but it was significantly higher than the baseline value (P < 0.05). Our findings showed that the deleterious effect on bone metabolism in hyperthyroidism might be mediated by cytokines and the increased bone turnover in hyperthyroidism failed to decrease despite euthyroidism.

Beta2-microglobuline plasma level and painful shoulder in haemodialysed patients.

PubMed

Barisić, Igor; Ljutić, Dragan; Vlak, Tonko; Bekavac, Josip; Perić, Irena; Mise, Kornelija; Klancnik, Marisa; Janković, Stipan

2010-03-01

Painful shoulder in patients on chronic haemodialyis is most often associated with dialysis arthropathy or accumulation of deposits containing modified fibrils of beta2- microglobuline especially in bones and joints due to insufficient elimination during the therapy. The aim of this study is to investigate whether there is connection between painful shoulder and plasma level of beta2-microglobuline and to corroborate that with morphologic parameters found in proved amyloidosis. It has to be emphasized that even other causes may contribute the development of painful shoulder. Real time sonography and conventional plain radiographs of the 108 shoulders were performed in 54 patients receiving chronic haemodialysis as a treatment of terminal renal failure (without previous history of rheumatoid arthritis), 27 symptomatic with persistent pain and stiffness in both shoulders and lasting for more than 6 weeks and restriction of movements in various degree and 27 asymptomatic. Plasma level of beta2-microglobuline, CRP and uric acid were taken periodically as routine procedure during a one year prospective trial, as well as plasma level of calcium, phosphor and alkaline phosphatase. Plasmatic level of beta2-microglobuline is strongly connected with painful shoulder in dialyzed patients, as well as CRP as sign of acute inflammation. That is proved by morphologic parameters associated with histological proved amyloidosis in patients on long term dialysis, more then 10 years.

The Influence of Magnetosheath Beta and Ionospheric Conductivity in the Structure of the Lobes Near Solstice

NASA Astrophysics Data System (ADS)

Wilder, F. D.; Eriksson, S.; Wiltberger, M. J.

2017-12-01

The saturation of the cross-polar cap potential (CPCP) is an unexplained phenomenon in magnetosphere-ionosphere system science. In the present study, we expand upon the Alfvén Wing model of CPCP saturation by investigating its impact on the magnetosphere-ionosphere current system, particularly the cusp-mantle dynamo associated with lobe field lines. In this expansion of the Alfven wing model, the ability of open flux tubes to deform in response to the fluid stress from the magnetosheath is governed by the magnetosheath plasma beta, which in turn reduces the Maxwell stress imposed on the ionospheric plasma to accelerate it against ion-neutral collisional drag. We perform 32 simulations using the Lyon-Fedder-Mobarry (LFM) Magnetohydrodynamic (MHD) model with varying solar wind density and IMF strength, as well as a dipole tilt of 25 degrees to investigate the relative importance of both magnetosheath plasma beta and ionospheric conductivity in the formation of Alfvén wing-like structures and the saturation of the CPCP. We find that the plasma beta in the magnetosheath is different in each hemisphere and dependent on the stagnation point location. We also show that the lobes become more bent in the summer hemisphere with higher ionospheric conductivity. We find that higher ionospheric conductivity also makes the summer hemisphere lobes more sensitive to changes in the magnetosheath beta.

Numerical Analysis of the Effects of Normalized Plasma Pressure on RMP ELM Suppression in DIII-D

DOE Office of Scientific and Technical Information (OSTI.GOV)

Orlov, D. M.; Moyer, R.A.; Evans, T. E.

2010-01-01

The effect of normalized plasma pressure as characterized by normalized pressure parameter (beta(N)) on the suppression of edge localized modes (ELMs) using resonant magnetic perturbations (RMPs) is studied in low-collisionality (nu* <= 0.2) H-mode plasmas with low-triangularity ( = 0.25) and ITER similar shapes ( = 0.51). Experimental results have suggested that ELM suppression by RMPs requires a minimum threshold in plasma pressure as characterized by beta(N). The variations in the vacuum field topology with beta(N) due to safety factor profile and island overlap changes caused by variation of the Shafranov shift and pedestal bootstrap current are examined numerically withmore » the field line integration code TRIP3D. The results show very small differences in the vacuum field structure in terms of the Chirikov (magnetic island overlap) parameter, Poincare sections and field line loss fractions. These differences do not appear to explain the observed threshold in beta(N) for ELM suppression. Linear peeling-ballooning stability analysis with the ELITE code suggests that the ELMs which persist during the RMPs when beta(N) is below the observed threshold are not type I ELMs, because the pedestal conditions are deep within the stable regime for peeling-ballooning modes. These ELMs have similarities to type III ELMs or low density ELMs.« less

Edge Stability and Performance of the ELM-Free Quiescent H-Mode and the Quiescent Double Barrier Mode on DIII-D

DOE Office of Scientific and Technical Information (OSTI.GOV)

West, W P; Burrell, K H; Casper, T A

2004-12-03

The quiescent H (QH) mode, an edge localized mode (ELM)-free, high-confinement mode, combines well with an internal transport barrier to form quiescent double barrier (QDB) stationary state, high performance plasmas. The QH-mode edge pedestal pressure is similar to that seen in ELMing phases of the same discharge, with similar global energy confinement. The pedestal density in early ELMing phases of strongly pumped counter injection discharges drops and a transition to QH-mode occurs, leading to lower calculated edge bootstrap current. Plasmas current ramp experiment and ELITE code modeling of edge stability suggest that QH-modes lie near an edge current stability boundary.more » At high triangularity, QH-mode discharges operate at higher pedestal density and pressure, and have achieved ITER level values of {beta}{sub PED} and {nu}*. The QDB achieves performance of {alpha}{sub N}H{sub 89} {approx} 7 in quasi-stationary conditions for a duration of 10 tE, limited by hardware. Recently we demonstrated stationary state QDB discharges with little change in kinetic and q profiles (q{sub 0} > 1) for 2 s, comparable to ELMing ''hybrid scenarios'', yet without the debilitating effects of ELMs. Plasma profile control tools, including electron cyclotron heating and current drive and neutral beam heating, have been demonstrated to control simultaneously the q profile development, the density peaking, impurity accumulation and plasma beta.« less

Toxicokinetics of lambda-cyhalothrin in rats.

PubMed

Anadón, A; Martínez, M; Martínez, M A; Díaz, M J; Martínez-Larrañaga, M R

2006-08-01

The toxicokinetics of lambda-cyhalothrin after single 20 mg kg(-1) oral and 3 mg kg(-1) intravenous doses were studied in rats. Serial blood samples were obtained after oral and intravenous administration. Liver, brain, spinal cord, sciatic nerve, vas deferens, anococcygeus and myenteric plexus tissue samples were also collected. Plasma, liver, hypothalamus, cerebellum, medulla oblongata, frontal cortex, striatum, hippocampus, midbrain, spinal cord, vas deferens, anococcygeus, myenteric plexus and sciatic nerve concentrations of lambda-cyhalothrin were determined by HPLC. The plasma and tissue concentration-time data for lambda-cyhalothrin were found to fit a two-compartment open model. For lambda-cyhalothrin, the elimination half-life (T1/2beta) and the mean residence time from plasma were 7.55 and 8.55 h after i.v. and 10.27 and 14.43 h after oral administration. The total plasma clearance was not influenced by dose concentration or route and reached a value of 0.060l h(-1)kg(-1). After i.v. administration, the apparent volume of distribution and at steady state were 0.68 and 0.53l kg(-1), suggesting a diffusion of the pyrethroid into tissue. After oral administration, lambda-cyhalothrin was extensively but slowly absorbed (Tmax, 2.69 h). The oral bioavailability was found to be 67.37%. Significant differences in the kinetic parameters between nervous tissues and plasma was observed. The maximum concentrations in hypothalamus (Cmax, 24.12 microg g(-1)) and myenteric plexus (Cmax, 25.12 microg g(-1)) were about 1.5 times higher than in plasma (Cmax, 15.65 microg ml(-1)) and 1.3 times higher than in liver (Cmax, 18.42 microg ml(-1)). Nervous tissue accumulation of lambda-cyhalothrin was also reflected by the area under the concentration curve ratios of tissue/plasma (liver). The T1/2beta for lambda-cyhalothrin was significantly greater for the nerve tissues, including neuromuscular fibres, (range 12-26 and 15-34 h, after i.v. and oral doses) than for plasma (7.55 and 10.27 h, respectively).

Determination of pharmacological levels of harmane, harmine and harmaline in mammalian brain tissue, cerebrospinal fluid and plasma by high-performance liquid chromatography with fluorimetric detection.

PubMed

Moncrieff, J

1989-11-24

Increased blood aldehyde levels, as occur in alcohol intoxication, could lead to the formation of beta-carbolines such as harmane by condensation with indoleamines. Endogenous beta-carbolines, therefore, should occur in specific brain areas where indoleamine concentrations are high, whilst exogenous beta-carbolines should exhibit an even distribution. The author presents direct and sensitive methods for assaying the beta-carbolines harmane, harmine and harmaline in brain tissue, cerebrospinal fluid and plasma at picogram sample concentrations using reversed-phase high-performance liquid chromatography with fluorimetric detection and minimal sample preparation. Using these assay methods, it was found that the distribution of beta-carbolines from a source exogenous to the brain results in a relatively even distribution within the brain tissue.

Overview of the Lockheed Martin Compact Fusion Reactor (CFR) Project

NASA Astrophysics Data System (ADS)

McGuire, Thomas

2017-10-01

The Lockheed Martin Compact Fusion Reactor (CFR) Program endeavors to quickly develop a compact fusion power plant with favorable commercial economics and military utility. The CFR uses a diamagnetic, high beta, magnetically encapsulated, linear ring cusp plasma confinement scheme. Major project activities will be reviewed, including the T4B and T5 plasma heating experiments. The goal of the experiments is to demonstrate a suitable plasma target for heating experiments, to characterize the behavior of plasma sources in the CFR configuration and to then heat the plasma with neutral beams, with the plasma transitioning into the high Beta confinement regime. The design and preliminary results of the experiments will be presented, including discussion of predicted behavior, plasma sources, heating mechanisms, diagnostics suite and relevant numerical modeling. ©2017 Lockheed Martin Corporation. All Rights Reserved.

Impact of beta-blocker treatment on the prognostic value of currently used risk predictors in congestive heart failure.

PubMed

Zugck, Christian; Haunstetter, Armin; Krüger, Carsten; Kell, Robert; Schellberg, Dieter; Kübler, Wolfgang; Haass, Markus

2002-05-15

This prospective study tested the impact of beta-blocker treatment on currently used risk predictors in congestive heart failure (CHF). Given the survival benefit obtained by beta-blockade, risk stratification by factors established in the "pre-beta-blocker era" may be questioned. The study included 408 patients who had CHF with left ventricular ejection fraction (LVEF) <45%, all treated with an angiotensin-converting enzyme inhibitor or angiotensin type 1 receptor antagonist, who were classified into those receiving a beta-blocker (n = 165) and those who were not (n = 243). In all patients, LVEF, peak oxygen consumption (peakVO(2)), plasma norepinephrine (NE) and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were determined. Although the New York Heart Association functional class (2.2 +/- 0.7 vs. 2.3 +/- 0.7), peakVO(2) (14.4 +/- 5.2 ml/min per kg vs. 14.4 +/- 5.5 ml/min per kg) and NT-proBNP (337 +/- 360 pmol/l vs. 434 +/- 538 pmol/l) were similar in the groups with and without beta-blocker treatment, the group with beta-blocker treatment had a lower heart rate (68 +/- 30 beats/min vs. 76 +/- 30 beats/min), lower NE (1.7 +/- 1.2 nmol/l vs. 2.5 +/- 2.2 nmol/l) and higher LVEF (24 +/- 10% vs. 21 +/- 9%; all p < 0.05). Within one year, 34% of patients without beta-blocker treatment, but only 16% of those with beta-blocker treatment (p < 0.001), reached the combined end point, defined as hospital admission due to worsening CHF and/or cardiac death. A beneficial effect of beta-blocker treatment was most obvious in the advanced stages of CHF, because the end-point rates were markedly lower (all p < 0.05) in the group with beta-blocker treatment versus the group without it, as characterized by peakVO(2) <10 ml/min per kg (26% vs. 64%), LVEF < or = 20% (25% vs. 45%), NE >2.24 nmol/l (18% vs. 40%) and NT-proBNP >364 pmol/l (27% vs. 45%), although patients with beta-blocker treatment received only 37 +/- 21% of the maximal recommended beta-blocker dosages. The prognostic value of variables used for risk stratification of patients with CHF is markedly influenced by beta-blocker treatment. Therefore, in the beta-blocker era, a re-evaluation of the selection criteria for heart transplantation is warranted.

Chocolate matrix factors modulate the pharmacokinetic behavior of cocoa flavan-3-ol phase II metabolites following oral consumption by Sprague-Dawley rats.

PubMed

Neilson, Andrew P; Sapper, Teryn N; Janle, Elsa M; Rudolph, Ralf; Matusheski, Nathan V; Ferruzzi, Mario G

2010-06-09

The impact of carbohydrates and milk on the bioavailability of catechin (C) and epicatechin (EC) from chocolate has been previously studied. However, little data exist regarding potential modulation of the phase II metabolism by these chocolate matrix factors. The objectives of this study were to assess the impact of matrix composition on qualitative and quantitative profiles of circulating catechins and their metabolites following administration of commercially relevant chocolate confections. Sprague-Dawley rats were administered 1.5 g of a confection (reference dark, high sucrose, or milk chocolate) by intragastric gavage, and plasma samples were collected over 8 h. High-performance liquid chromatography-mass spectrometry analysis was performed to quantify C, EC, and their metabolites. The predominant metabolites were O-glucuronides (two metabolites) and O-Me-O-glucuronides (three metabolites). Plasma concentrations of metabolites were generally the highest for high sucrose treatment and lowest for milk treatment, while the reference dark treatment generally resulted in intermediate concentrations. The O-Me-(+/-)-C/EC-O-beta-glucuronide (peak 4) was significantly higher for the high sucrose treatment (2325 nM h) versus the milk treatment (1300 nM h). Additionally, C(MAX) values for (+/-)-C/EC-O-beta-glucuronide (peak 3) and two O-Me-(+/-)-C/EC-O-beta-glucuronides (peaks 4 and 6) were significantly higher for the high sucrose treatment (4012, 518, and 2518 nM, respectively) versus the milk treatment (2590, 240, and 1670 nM, respectively). Milk and sucrose appear to modulate both metabolism and plasma pharmacokinetics and, to a lesser extent, the overall bioavailability of catechins from chocolate confections.

Plasma pharmacokinetics and metabolism of 13-cis- and all-trans-retinoic acid in the cynomolgus monkey and the identification of 13-cis- and all-trans-retinoyl-beta-glucuronides. A comparison to one human case study with isotretinoin.

PubMed

Kraft, J C; Slikker, W; Bailey, J R; Roberts, L G; Fischer, B; Wittfoht, W; Nau, H

1991-01-01

In order to compare the disposition and metabolism of 13-cis-retinoic acid (13-cis-RA) and all-trans-retinoic acid (all-trans-RA) in the nonpregnant female cynomolgus monkey, the plasma concentrations of the parent compound, the oxidized metabolites 4-oxo-13-cis-retinoic acid and 4-oxo-all-trans-retinoic acid, and the conjugate metabolites 13-cis-retinoyl-beta-glucuronide (13-cis-RAG) and all trans-retinoyl-beta-glucuronide (all-trans-RAG), were determined on day 1 and day 10 after oral dosing of 2 and 10 mg 13-cis- and all-trans-RA/kg/day. Both 13-cis-RAG and all-trans-RAG have been identified as major plasma metabolites in these studies using thermospray/HPLC/mass-spectrometry of the intact conjugates. AUC comparisons from 0-24 hr after administration indicated that 13-cis-RA treatment resulted in primarily cis metabolites and all-trans-RA treatment resulted in primarily trans metabolites, although low levels of isomerization products were observed. Comparison of the two doses (2 and 10 mg/kg, po) revealed that the AUCs were proportional to the dose administered. Although qualitatively similar, elimination of 13-cis-RA in the monkey was more rapid than in the human, and approximately a 10-fold greater dose of 13-cis-RA was required in the monkey to produce the AUC values comparable to the human. The elimination of all-trans-RA in monkey was faster than that of 13-cis-RA and tended to increase with repeated dosing.(ABSTRACT TRUNCATED AT 250 WORDS)

Nuchal translucency measurement, free β-hCG and PAPP-A concentrations in IVF/ICSI pregnancies: systematic review and meta-analysis.

PubMed

Cavoretto, Paolo; Giorgione, Veronica; Cipriani, Sonia; Viganò, Paola; Candiani, Massimo; Inversetti, Annalisa; Ricci, Elena; Parazzini, Fabio

2017-06-01

So far, data on the effect of assisted reproductive technologies (ART) on the components of first trimester combined screening for Down syndrome are still controversial. A systematic search of the literature was performed in order to identify the effect of ART, particularly in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) with fresh embryo transfer, on the nuchal translucency, free beta-human chorionic gonadotrophin and pregnancy-associated plasma protein-A measurements. Moreover, a meta-analysis and a descriptive graphical representation of the ratios between ART and spontaneous pregnancies (controls) values of median of the multiple of median (m 0 MoM) were performed. Free beta-human chorionic gonadotrophin test showed slightly higher values in the ICSI group than controls (RR = 1.09, 95%CI: 1.03-1.16) but not in the IVF group (RR = 1.03, 95%CI: 0.94-1.12). Pregnancy-associated plasma protein-A values for IVF/ICSI, IVF and ICSI showed lower values in comparison with controls (RR, 95%CI 0.85, 0.80-0.90; 0.82, 0.74-0.89 and 0.83, 0.79-0.86, respectively). The nuchal translucency measurement did not show any statistical differences between study groups (IVF and ICSI) and controls (RR = 1.00, 95%CI: 0.94-1.08 and RR = 1.01, 95%CI: 0.97-1.05, respectively). These results may be due to alterations in the placentation of ART pregnancies. Differentiating further subgroups of ART pregnancies may explain the differences in biomarker concentrations, in prenatal behavior and in obstetric outcomes between ART and spontaneous pregnancies. © 2017 John Wiley & Sons, Ltd. © 2017 John Wiley & Sons, Ltd.

Effects of intravenous temazepam. II. A study of the long-term reproducibility of pharmacokinetics, pharmacodynamics, and concentration-effect parameters.

PubMed

van Steveninck, A L; Schoemaker, H C; den Hartigh, J; Pieters, M S; Breimer, D D; Cohen, A F

1994-05-01

To evaluate the long-term reproducibility of pharmacokinetic, pharmacodynamic, and concentration-effect parameters after intravenous administration of temazepam. Nine healthy volunteers were studied. Temazepam, 0.4 mg/kg, was infused intravenously for 30 minutes on two occasions 6 months apart. Venous plasma concentrations of temazepam were measured by HPLC in samples obtained between 0 and 24 hours. Pharmacodynamic effects were evaluated up to 8 hours for saccadic peak velocity and electroencephalogram (EEG) beta amplitudes. Subjects' state and trait anxiety were assessed by use of the Spielberger anxiety inventory. Significant correlations between occasions were found for area under the plasma concentration-time curve (AUC) values (r = 0.91; p < 0.01) but not for maximum concentration and half-life. Significant correlations were also found for area under the effect-time curve (AUEC) values of peak velocity (r = 0.88; p < 0.01) but not for peak velocity (r = 0.48; p > 0.05). Significant differences between the slopes of concentration effect plots on different occasions were observed in two subjects for EEG beta and in three subjects for peak velocity, with one subject showing a similar change for both parameters. Trait anxiety scores were higher on the first occasion (33 +/- 7) than on the second occasion (29 +/- 7; p < 0.01). A negative correlation was found between trait anxiety scores and the slopes of concentration-effect plots for peak velocity (r = -0.63; p < 0.01). For AUC and AUEC values the results indicate a reasonable long-term reproducibility of differences between subjects in the pharmacokinetics and pharmacodynamics of temazepam. However, there were limitations to the predictive value of derived concentration-effect parameters.

ASCA X-ray spectra of the active single stars Beta Ceti and pi(1) Ursae Majoris

NASA Technical Reports Server (NTRS)

Drake, S. A.; Singh, K. P.; White, N. E.; Simon, Theodore

1994-01-01

We present X-ray spectra obtaiined by ASCA of two single, active stars, the G dwarf pi(1) UMa, and the G9/K0 giant Beta Cet. The spectra of both stars require the presence of at least two plasma components with different temperatures, 0.3-0.4 keV and approximately 0.7 keV, in order for acceptable fits to be obtained. The spectral resolving power and signal-to-noise ratio of the solid state imaging spectrometer (SIS) spectra allow us to formally constrain the coronal abundances of a number of elements. In Beta Cet, we find Mg to be overabundant, while other elements such as O, Ne, and N are underabundant, relative to the solar photospheric values. From the lower signal-to-noise ratio SIS spectrum of pi(1) UMa, we find evidence for underabundances of O, Ne, and Fe. These results are discussed in the context of the present understanding of elemental abundances in solar and stellar coronae.

Magnetic spectral signatures in the Earth's magnetosheath and plasma depletion layer

NASA Technical Reports Server (NTRS)

Anderson, Brian J.; Fuselier, Stephen A.; Gary, S. Peter; Denton, Richard E.

1994-01-01

Correlations between plasma properties and magnetic fluctuations in the sub-solar magnetosheath downstream of a quasi-perpendicular shock have been found and indicate that mirror and ion cyclotronlike fluctuations correlate with the magnetosheath proper and plasma depletion layer, respectively (Anderson and Fueselier, 1993). We explore the entire range of magnetic spectral signatures observed from the Active Magnetospheric Particle Tracer Explorers/Charge Composition Explorer (AMPTE/CCE)spacecraft in the magnetosheath downstream of a quasi-perpendicular shock. The magnetic spectral signatures typically progress from predominantly compressional fluctuations,delta B(sub parallel)/delta B perpendicular to approximately 3, with F/F (sub p) less than 0.2 (F and F (sub p) are the wave frequency and proton gyrofrequency, respectively) to predominantly transverse fluctuations, delta B(sub parallel)/delta B perpendicular to approximately 0.3, extending up to F(sub p). The compressional fluctuations are characterized by anticorrelation between the field magnitude and electron density, n(sub e), and by a small compressibility, C(sub e) identically equal to (delta n(sub e)/n(sub e)) (exp 2) (B/delta B(sub parallel)) (exp 2) approximately 0.13, indicative of mirror waves. The spectral characteristics of the transverse fluctuations are in agreement with predictions of linear Vlasov theory for the H(+) and He(2+) cyclotron modes. The power spectra and local plasma parameters are found to vary in concert: mirror waves occur for beta(s ub parallel p) (beta (sub parallel p) identically = 2 mu(sub zero) n(sub p) kT (sub parallel p) / B(exp 2) approximately = 2, A(sub p) indentically = T(sub perpendicular to p)/T(sub parallel p) - 1 approximately = 0.4, whereas cyclotron waves occur for beta (sub parallel p) approximately = 0.2 and A(sub p) approximately = 2. The transition from mirror to cyclotron modes is predicted by linear theory. The spectral characteristics overlap for intermediate plasma parameters. The plasma observations are described by A(sub p) = 0.85 beta(sub parallel P) (exp - 0.48) with a log regression coefficient of -0.74. This inverse A(sub p) - beta(sub parallel p) correlation corresponds closely to the isocontours of maximum ion anisotropy instability growth, gamma (sub m)/omega(sub p) = 0.01, for the mirror and cyclotron modes. The agreement of observed properties and predictions of local theory suggests that the spectral signatures reflect the local plasma environment and that the anisotropy instabilities regulate A(sub p). We suggest that the spectral characteristics may provide a useful basis for ordering observations in the magnetosheath and that the A(sub p) - beta(sub parallel p) inverse correlation may be used as a beta-dependent upper limit on the proton anisotropy to represent kinetic effects.

Drift kinetic effects on plasma response in high beta spherical tokamak experiments

NASA Astrophysics Data System (ADS)

Wang, Zhirui; Park, Jong-Kyu; Menard, Jonathan E.; Liu, Yueqiang; Kaye, Stanley M.; Gerhardt, Stefan

2018-01-01

The high β plasma response to rotating n=1 external magnetic perturbations is numerically studied and compared with the National Spherical Torus Experiment (NSTX). The hybrid magnetohydrodynamic(MHD)-kinetic modeling shows that drift kinetic effects are important in resolving the disagreement of plasma response between the ideal MHD prediction and the NSTX experimental observation when plasma pressure reaches and exceeds the no-wall limit (Troyon et al 1984 Plasma Phys. Control. Fusion 26 209). Since the external rotating fields and high plasma rotation are presented in the NSTX experiments, the importance of the resistive wall effect and plasma rotation in determining the plasma response is also identified, where the resistive wall suppresses the plasma response through the wall eddy current. The inertial energy due to plasma rotation destabilizes the plasma. The complexity of the plasma response in this study indicates that MHD modeling, including comprehensive physics, e.g. the drift kinetic effects, resistive wall and plasma rotation, are essential in order to reliably predict the plasma behavior in a high beta spherical tokamak device.

The influence of feeding and fasting on plasma metabolites in the dogfish shark (Squalus acanthias).

PubMed

Wood, Chris M; Walsh, Patrick J; Kajimura, Makiko; McClelland, Grant B; Chew, Shit F

2010-04-01

Dogfish sharks are opportunistic predators, eating large meals at irregular intervals. Here we present a synthesis of data from several previous studies on responses in plasma metabolites after natural feeding and during prolonged fasting (up to 56days), together with new data on changes in plasma concentrations of amino acids and non-esterified fatty acids. Post-prandial and long-term fasting responses were compared to control sharks fasted for 7days, a typical inter-meal interval. A feeding frenzy was created in which dogfish were allowed to feed naturally on dead teleosts at two consumed ration levels, 2.6% and 5.5% of body weight. Most responses were more pronounced at the higher ration level. These included increases in urea and TMAO concentrations at 20h, followed by stability through to 56days of fasting. Ammonia levels were low and exhibited little short-term response to feeding, but declined to very low values during the extended fast. Glucose and beta-hydroxybutyrate both fell after feeding, the latter to a greater and more prolonged extent (up to 60h), whereas acetoacetate did not change. During prolonged fasting, glucose concentrations were well regulated, but beta-hydroxybutyrate increased to 2-3-fold control levels. Total plasma amino acid concentrations increased in a biphasic fashion, with peaks at 6-20h, and 48-60h after the meal, followed by homeostasis during the extended fast. Essential and non-essential amino acids generally followed this same pattern, though some exhibited different trends after feeding: taurine, beta-alanine, and glycine (decreases or stability), alanine and glutamine (modest prolonged increases), and threonine, serine, asparagine, and valine (much larger short-term increases). Plasma non-esterified fatty acid concentrations declined markedly through 48h after the 2.6% meal. These data are interpreted in light of companion studies showing elevations in aerobic metabolic rate, urea production, rectal gland function, metabolic base excretion, and activation of ornithine-urea cycle and aerobic enzymes after the meal, and muscle N-depletion but maintenance of osmolality and urea production during long-term fasting.

Initial transport validation studies using NSTX-U L-mode plasmas

NASA Astrophysics Data System (ADS)

Guttenfelder, Walter; Battaglia, D.; Bell, R. E.; Boyer, M. D.; Crocker, N.; Diallo, A.; Ferraro, N.; Gerhardt, S. P.; Kaye, S. M.; Leblanc, B. P.; Liu, D.; Menard, J. E.; Mueller, D.; Myer, C.; Podesta, M.; Raman, R.; Ren, Y.; Sabbagh, S.; Smith, D.

2016-10-01

A variety of stationary L-mode plasmas have been successfully developed in NSTX-U for physics validation studies. The plasmas span a range of density (1-4 ×1019 m-3) , plasma current (0.65-1.0 MA), and neutral beam heating power (<=4 MW), taking advantage of new, more tangential neutral beam sources to vary rotation profiles. Transport analysis (TRANSP) and turbulence measurements (BES, reflectometry) of these plasmas will be illustrated and compared with initial microstability and transport predictions. In particular, the normalized beta of these L-modes range between βN = 1-2, providing a valuable bridge in parameter space between (i) H-modes at comparable beta in conventional tokamaks (R/a 3, βN 2), where transport models have been largely developed and tested, and (ii) low-aspect-ratio H-modes at higher beta (R/a 1.5-1.7, βN 5), where transport models are less tested and challenged by stronger electromagnetic and equilibrium effects. This work is supported by US DOE contract DE-AC02-09CH11466.

Influence of estradiol and androstenedione on ACTH and cortisol secretion in the ovine fetus.

PubMed

Wood, C E; Saoud, C J

1997-01-01

To test the hypothesis that physiologic increases in fetal plasma 17 beta-estradiol and androstenedione modulate the activity of the fetal hypothalamic-pituitary-adrenal (HPA) axis. Seventeen pregnant ewes and their fetuses were chronically catheterized. At the time of surgery, the fetuses received implants that released 17 beta-estradiol (n = 5) alone or 17 beta-estradiol and androstenedione (n = 6), each at a rate of approximately 250 micrograms/day for each steroid. The control group (n = 6) received either no pellet (n = 2) or a "placebo" pellet, which contained no steroid (n = 4). Fetal blood samples were drawn for hormone and blood gas analysis at 1-3-day intervals until the time of spontaneous parturition. Fetal plasma ACTH and cortisol concentrations were fit to semilogarithmic equations and analyzed by stepwise multiple linear regression analysis for statistically significant effects of 17 beta-estradiol and androstenedione. Estradiol significantly increased and androstenedione significantly decreased the ACTH and cortisol concentrations. Treatment with both 17 beta-estradiol and androstenedione resulted in parturition approximately 4 days earlier than in the other groups (P < .05). Physiologic increases in fetal plasma estradiol and androstenedione modify the activity of the HPA axis.

EFFECTS OF THE TEMPERATURE ANISOTROPY ON THE MASER INSTABILITY EXCITED BY LOWER ENERGY CUTOFF BEHAVIOR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tang, J. F.; Wu, D. J.; Yan, Y. H., E-mail: djwu@pmo.ac.cn, E-mail: djwu@pmo.ac.cn

The electron-cyclotron maser (ECM) conventionally driven by velocity anisotropies of energetic electrons trapped in magnetic fields is one of the most important radio-emission mechanisms in astrophysics. Recently, Wu and Tang proposed that a proper lower energy cutoff behavior of power-law electrons can effectively excite the ECM emission. This paper considers effects of temperature anisotropy on this new ECM mechanism. The results show that the growth rates of the ECM emissions increase with {beta}{sub perpendicular0} and {beta}{sub ||0}, where {beta}{sub perpendicular0} and {beta}{sub ||0} are the perpendicular and parallel velocity spreads (in units of the light velocity c) of the energeticmore » electron beam, respectively. Moreover, the growth rates of O1 and X2 modes both sensitively depend on the ratio of the electron-cyclotron frequency to the plasma frequency {Omega} and reach their extremum values at {Omega} {approx_equal} 1.5 for the O1 mode and at {Omega} {approx_equal} 1.0 for the X2 mode. Meanwhile, as the mean velocity of the electron beam {beta}{sub s} (in units of c) increases, the growth rate of the O1 mode remains approximately constant and that of the X2 mode decreases considerably.« less

Effects of fast ions on interchange modes in the Large Helical Device plasmas

NASA Astrophysics Data System (ADS)

Pinon, Jonhathan; Todo, Yasushi; Wang, Hao

2018-07-01

Effects of fast ions on the magnetohydrodynamic (MHD) instabilities in a Large Helical Device (LHD) plasma with the central beta value (=pressure normalized by the magnetic pressure) 4% have been investigated with hybrid simulations for energetic particles interacting with an MHD fluid. When fast ions are neglected, it is found that the dominant instability is an ideal interchange mode with the dominant harmonic m/n = 2/1, where m, n are respectively the poloidal and toroidal numbers. The spatial peak location of the m/n = 2/1 harmonic is close to the ι = 1/2 magnetic surface located at r/a = 0.29, where ι is the rotational transform and r/a is the normalized radius. The second unstable mode is a resistive interchange mode with m/n =3/2 that peaks at r/a = 0.65 nearby the ι = 2/3 surface, which grows more slowly than the m/n = 2/1 mode. The nonlinear coupling of the m/n = 3/2 and 2/1 mode results in the growth of the m/n = 5/3 mode and other modes leading to the global reduction and flattening of the pressure profile. When fast ions are considered with the central beta value 0.2% and the total pressure profile is kept the same, the ideal interchange mode with m/n = 2/1 located close to the plasma center is stabilized while the resistive interchange mode with m/n = 3/2 located far from the plasma center is less affected. The stabilization is attributed to the reduction of bulk pressure gradient, which is the dilution of the free energy source, because the energy transfer between the fast ions and the interchange modes is found to be negligible. For higher fast-ion pressure, Alfvén eigenmodes are destabilized by fast ions.

Drift kinetic effects on the plasma response in high beta spherical tokamak experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Zhirui; Park, Jong-Kyu; Menard, Jonathan E.

The high β plasma response to rotating n = 1 external magnetic perturbations is numerically studied and compared with the National Spherical Torus Experiment (NSTX). The hybrid magnetohydrodynamic(MHD)-kinetic modeling shows that drift kinetic effects are important in resolving the disagreement of plasma response between the ideal MHD prediction and the NSTX experimental observation when plasma pressure reaches and exceeds the no-wall limit. Since the external rotating fields and high plasma rotation are presented in the NSTX experiments, the importance of the resistive wall effect and plasma rotation in determining the plasma response is also identified, where the resistive wall suppressesmore » the plasma response through the wall eddy current. The inertial energy due to plasma rotation destabilizes the plasma. In conclusion, the complexity of the plasma response in this study indicates that MHD modeling, including comprehensive physics, e.g. the drift kinetic effects, resistive wall and plasma rotation, are essential in order to reliably predict the plasma behavior in a high beta spherical tokamak device.« less

Drift kinetic effects on the plasma response in high beta spherical tokamak experiments

DOE PAGES

Wang, Zhirui; Park, Jong-Kyu; Menard, Jonathan E.; ...

2017-09-21

The high β plasma response to rotating n = 1 external magnetic perturbations is numerically studied and compared with the National Spherical Torus Experiment (NSTX). The hybrid magnetohydrodynamic(MHD)-kinetic modeling shows that drift kinetic effects are important in resolving the disagreement of plasma response between the ideal MHD prediction and the NSTX experimental observation when plasma pressure reaches and exceeds the no-wall limit. Since the external rotating fields and high plasma rotation are presented in the NSTX experiments, the importance of the resistive wall effect and plasma rotation in determining the plasma response is also identified, where the resistive wall suppressesmore » the plasma response through the wall eddy current. The inertial energy due to plasma rotation destabilizes the plasma. In conclusion, the complexity of the plasma response in this study indicates that MHD modeling, including comprehensive physics, e.g. the drift kinetic effects, resistive wall and plasma rotation, are essential in order to reliably predict the plasma behavior in a high beta spherical tokamak device.« less

Preparation of a Homologous (Human) Intravenous Botulinal Immune Globulin.

DTIC Science & Technology

1983-05-01

lipoprotein ( HDL ) per ml of plasma to ŗ.06 mg/ml for beta- lipoprotein (LDL). Triglyceride and cholesterol levels were intermediate within this...OF LIPOPROTEIN DURING FRACTIONATION "( HDL ) (LDL) Triglyceride Cholesterol cxLipoprotein 8 LipoproteinSample mg/ml mg/ml mg/mi m/ml IVBG-l.A:"Plasma...plasminogen, prekallikrein, triglycerides , cholesterol , alpha- lipoprotein , beta- lipoprotein , clotting factors, fibrinogen and complement

Reduction of elevated plasma globotriaosylsphingosine in patients with classic Fabry disease following enzyme replacement therapy.

PubMed

van Breemen, Mariëlle J; Rombach, Saskia M; Dekker, Nick; Poorthuis, Ben J; Linthorst, Gabor E; Zwinderman, Aeilko H; Breunig, Frank; Wanner, Christoph; Aerts, Johannes M; Hollak, Carla E

2011-01-01

Fabry disease is treated by two-weekly infusions with α-galactosidase A, which is deficient in this X-linked globotriaosylceramide (Gb3) storage disorder. Elevated plasma globotriaosylsphingosine (lysoGb3) is a hallmark of classical Fabry disease. We investigated effects of enzyme replacement therapy (ERT) on plasma levels of lysoGb3 and Gb3 in patients with classical Fabry disease treated with agalsidase alfa at 0.2mg/kg, agalsidase beta at 0.2mg/kg or at 1.0mg/kg bodyweight. Each treatment regimen led to prominent reductions of plasma lysoGb3 in Fabry males within 3 months (P=0.0313), followed by relative stability later on. Many males developed antibodies against α-galactosidase A, particularly those treated with agalsidase beta. Patients with antibodies tended towards smaller correction in plasma lysoGb3 concentration, whereas treatment with high dose agalsidase beta allowed a reduction comparable to patients without antibodies. Pre-treatment plasma lysoGb3 concentrations of Fabry females were relatively low. In all females and with each treatment regimen, ERT gave reduction or stabilisation of plasma lysoGb3. Our investigation revealed that ERT of Fabry patients reduces plasma lysoGb3, regardless of the recombinant enzyme used. This finding shows that ERT can correct a characteristic biochemical abnormality in Fabry patients. Copyright © 2010 Elsevier B.V. All rights reserved.

Basal and glucagon-stimulated plasma C-peptide concentrations in healthy dogs, dogs with diabetes mellitus, and dogs with hyperadrenocorticism.

PubMed

Montgomery, T M; Nelson, R W; Feldman, E C; Robertson, K; Polonsky, K S

1996-01-01

Serum glucose and plasma C-peptide response to i.v. glucagon administration was evaluated in 24 healthy dogs, 12 dogs with untreated diabetes mellitus, 30 dogs with insulin-treated diabetes mellitus, and 8 dogs with naturally acquired hyperadrenocorticism. Serum insulin response also was evaluated in all dogs, except 20 insulin-treated diabetic dogs. Blood samples for serum glucose, serum insulin, and plasma C-peptide determinations were collected immediately before and 5, 10, 20, 30, and (for healthy dogs) 60 minutes after i.v. administration of 1 mg glucagon per dog. In healthy dogs, the patterns of glucagon-stimulated changes in plasma C-peptide and serum insulin concentrations were identical, with single peaks in plasma C-peptide and serum insulin concentrations observed approximately 15 minutes after i.v. glucagon administration. Mean plasma C-peptide and serum insulin concentrations in untreated diabetic dogs, and mean plasma C-peptide concentration in insulin-treated diabetic dogs did not increase significantly after i.v. glucagon administration. The validity of serum insulin concentration results was questionable in 10 insulin-treated diabetic dogs, possibly because of anti-insulin antibody interference with the insulin radioimmunoassay. Plasma C-peptide and serum insulin concentrations were significantly increased (P < .001) at all blood sampling times after glucagon administration in dogs with hyperadrenocorticism, compared with healthy dogs, and untreated and insulin-treated diabetic dogs. Five-minute C-peptide increment, C-peptide peak response, total C-peptide secretion, and, for untreated diabetic dogs, insulin peak response and total insulin secretion were significantly lower (P < .00l) in diabetic dogs, compared with healthy dogs, whereas these same parameters were significantly increased (P < .01) in dogs with hyperadrenocorticism, compared with healthy dogs, and untreated and insulin-treated diabetic dogs. Although not statistically significant, there was a trend for higher plasma C-peptide concentrations in untreated diabetic dogs compared with insulin-treated diabetic dogs during the glucagon stimulation test. Baseline C-peptide concentrations also were significantly higher (P < .05) in diabetic dogs treated with insulin for less than 6 months, compared with diabetic dogs treated for longer than 1 year. Finally, 7 of 42 diabetic dogs had baseline plasma C-peptide concentrations greater than 2 SD (ie, > 0.29 pmol/mL) above the normal mean plasma C-peptide concentration; values that were significantly higher, compared with the results in healthy dogs (P < .001) and with the other 35 diabetic dogs (P < .001). In summary, measurement of plasma C-peptide concentration during glucagon stimulation testing allowed differentiation among healthy dogs, dogs with impaired beta-cell function (ie, diabetes mellitus), and dogs with increased beta-cell responsiveness to glucagon (ie, insulin resistance). Plasma C-peptide concentrations during glucagon stimulation testing were variable in diabetic dogs and may represent dogs with type-1 and type-2 diabetes or, more likely, differences in severity of beta-cell loss in dogs with type-1 diabetes.

The cellular distribution of fluorescently labeled arrestins provides a robust, sensitive, and universal assay for screening G protein-coupled receptors.

PubMed

Oakley, Robert H; Hudson, Christine C; Cruickshank, Rachael D; Meyers, Diane M; Payne, Richard E; Rhem, Shay M; Loomis, Carson R

2002-11-01

G protein-coupled receptors (GPCRs) have proven to be a rich source of therapeutic targets; therefore, finding compounds that regulate these receptors is a critical goal in drug discovery. The Transfluor technology utilizes the redistribution of fluorescently labeled arrestins from the cytoplasm to agonist-occupied receptors at the plasma membrane to monitor quantitatively the activation or inactivation of GPCRs. Here, we show that the Transfluor technology can be quantitated on the INCell Analyzer system (INCAS) using the vasopressin V(2) receptor (V(2)R), which binds arrestin with high affinity, and the beta(2)-adrenergic receptor (beta(2)AR), which binds arrestin with low affinity. U2OS cells stably expressing an arrestin-green fluorescent protein conjugate and either the V(2)R or the beta(2)AR were plated in 96-well plastic plates and analyzed by the INCAS at a screening rate of 5 min per plate. Agonist dose-response and antagonist dose-inhibition curves revealed signal-to-background ratios of approximately 25:1 and 8:1 for the V(2)R and beta(2)AR, respectively. EC(50) values agreed closely with K(d) values reported in the literature for the different receptor agonists. In addition, small amounts of arrestin translocation induced by sub-EC(50) doses of agonist were distinguished from the background noise of untreated cells. Furthermore, differences in the magnitude of arrestin translocation distinguished partial agonists from full agonists, and Z' values for these ligands were >0.5. These data show that the Transfluor technology, combined with an automated image analysis system, provides a direct, robust, and universal assay for high throughput screening of known and orphan GPCRs.

Overview of LDX Results

NASA Astrophysics Data System (ADS)

Kesner, J.; Boxer, A. C.; Ellsworth, J. L.; Karim, I.; Garnier, D. T.; Hansen, A. K.; Mauel, M. E.; Ortiz, E. E.

2006-10-01

The levitated dipole experiment (LDX) is a new research facility that is investigating plasma confinement and stability in a dipole magnetic field configuration as a possible catalyzed DD fusion power source that would avoid the burning of tritium. We report the production of high beta plasma confined by a laboratory superconducting dipole using neutral gas fueling and electron cyclotron resonance heating (ECRH). The pressure results from a population of anisotropic energetic trapped electrons that is sustained by microwave heating provided sufficient neutral gas is supplied to the plasma. The trapped electron beta was observed to be limited by the hot electron interchange (HEI) instability, but when the neutral gas was programmed so as to maintain the deuterium gas pressure near 0.2 mPa, the fast electron pressure increased by more than a factor of ten and the resulting stable high beta plasma was maintained quasi-continuously for up to 14 seconds. Low frequency (<10 kHz) fluctuations are sometimes observed at low neutral base pressure.

Stress-related hormones in horses before and after stunning by captive bolt gun.

PubMed

Micera, Elisabetta; Albrizio, Maria; Surdo, Nicoletta C; Moramarco, Angela M; Zarrilli, Antonia

2010-04-01

In this work the slaughter-linked plasma modifications of some stress-related hormones in horses subject to standardized butchering procedures were investigated in order to highlight the compromised animal welfare during pre-slaughter handling. During pre-slaughter, animals show strong hardship behavioural patterns, probably due to being under life-threatening conditions. Blood samples from 12 male horses, ageing from 3 to 5 years, were collected before slaughtering in lairage, and during exsanguination after stunning. Catecholamines, cortisol and beta-endorphin concentrations were assessed in plasma samples by EIA. Results show that plasma beta-endorphin concentration did not increase significantly after stunning, while cortisol (P<0.05) and catecholamines (P<0.001) increased significantly. The ratio between the plasma level of norepinephrine and epinephrine decreased significantly (P<0.001) during the time considered for observation underlining a greater involvement of adrenal medulla in the stress response. Moreover these results suggest that, under stress, the release of beta-endorphin could be different from that of ACTH. 2009 Elsevier Ltd. All rights reserved.

Effect of Beta-Hydroxy Beta-Methylbutyrate on the Onset of Blood Lactate Accumulation and VO2peak in Endurance-Trained Cyclists.

ERIC Educational Resources Information Center

Vukovich, Matthew D.; Dreifort, Geri D.

2001-01-01

Examined the effect of beta-hydroxy beta-methylbutyrate (HMB) supplementation on maximal oxygen consumption (VO2peak) and onset of blood lactate accumulation (OBLA) in endurance-trained cyclists. Acute exercise did not affect plasma HMB concentrations. OBLA increased with HMB and leucine, with blood glucose significantly greater during the HMB…

Enhancing surface functionality of reduced graphene oxide biosensors by oxygen plasma treatment for Alzheimer's disease diagnosis.

PubMed

Chae, Myung-Sic; Kim, Jinsik; Jeong, Dahye; Kim, YoungSoo; Roh, Jee Hoon; Lee, Sung Min; Heo, Youhee; Kang, Ji Yoon; Lee, Jeong Hoon; Yoon, Dae Sung; Kim, Tae Geun; Chang, Suk Tai; Hwang, Kyo Seon

2017-06-15

We performed oxygen plasma treatment on reduced graphene oxide (rGO) to improve its surface reactivity with respect to biomolecular interactions. Oxygen-plasma-treated rGO surfaces were employed as reactive interfaces for the detection of amyloid-beta (Aβ) peptides, the pathological hallmarks of Alzheimer's disease (AD), as the target analytes. By measuring the changes in electrical characteristics and confirmation through topographic analysis, the oxygen-plasma-treated rGO sensors had enhanced surface functionality for better antibody immobilization and sensing performance, with a 3.33-fold steeper slope for the electrical responses versus analyte concentration curve (logarithmic scale) compared to the untreated. The elicited biomolecular reactivity of the rGO surfaces with the oxygen plasma treatment remained at 46-51% of the initial value even after aging for 6h in ambient conditions. This phenomenon was also confirmed by pretreating the rGO surfaces with a blocking agent and subsequently subjecting them to antibody immobilization. Finally, the feasibility of the oxygen-plasma-treated rGO sensors as a diagnostic tool was evaluated with clinical samples of neural-derived exosomal Aβ peptides extracted from apparent AD patients and normal controls (NC). In contrast to the untreated sensors (p=0.0460), the oxygen-plasma-treated rGO sensors showed a significant p-value in the identification of clinical samples of AD and NC subjects (p<0.001). These results suggest that oxygen plasma treatment improves sensor performance without complicated fabrication procedures and should aid in the development of novel diagnostic tools based on carbon nanomaterials. Copyright © 2016 Elsevier B.V. All rights reserved.

The Golgi localization of phosphatidylinositol transfer protein beta requires the protein kinase C-dependent phosphorylation of serine 262 and is essential for maintaining plasma membrane sphingomyelin levels.

PubMed

van Tiel, Claudia M; Westerman, Jan; Paasman, Marten A; Hoebens, Martha M; Wirtz, Karel W A; Snoek, Gerry T

2002-06-21

Recombinant mouse phosphatidylinositol transfer protein (PI-TP)beta is a substrate for protein kinase C (PKC)-dependent phosphorylation in vitro. Based on site-directed mutagenesis and two-dimensional tryptic peptide mapping, Ser(262) was identified as the major site of phosphorylation and Ser(165) as a minor phosphorylation site. The phospholipid transfer activities of wild-type PI-TP beta and PI-TP beta(S262A) were identical, whereas PI-TP beta(S165A) was completely inactive. PKC-dependent phosphorylation of Ser(262) also had no effect on the transfer activity of PI-TP beta. To investigate the role of Ser(262) in the functioning of PI-TP beta, wtPI-TP beta and PI-TP beta(S262A) were overexpressed in NIH3T3 fibroblast cells. Two-dimensional PAGE analysis of cell lysates was used to separate PI-TP beta from its phosphorylated form. After Western blotting, wtPI-TP beta was found to be 85% phosphorylated, whereas PI-TP beta(S262A) was not phosphorylated. In the presence of the PKC inhibitor GF 109203X, the phosphorylated form of wtPI-TP beta was strongly reduced. Immunolocalization showed that wtPI-TP beta was predominantly associated with the Golgi membranes. In the presence of the PKC inhibitor, wtPI-TP beta was distributed throughout the cell similar to what was observed for PI-TP beta(S262A). In contrast to wtPI-TP beta overexpressors, cells overexpressing PI-TP beta(S262A) were unable to rapidly replenish sphingomyelin in the plasma membrane upon degradation by sphingomyelinase. This implies that PKC-dependent association with the Golgi complex is a prerequisite for PI-TP beta to express its effect on sphingomyelin metabolism.

Factors influencing zinc status of apparently healthy indians.

PubMed

Agte, Vaishali V; Chiplonkar, Shashi A; Tarwadi, Kirtan V

2005-10-01

To identify dietary, environmental and socio-economic factors associated with mild zinc deficiency, three zinc status indices; erythrocyte membrane zinc (RBCMZn), plasma zinc and super oxide dismutase (SOD) were assessed in free living and apparently healthy Indian population. Dietary patterns of 232 men and 223 women (20-65 yr) from rural, industrial and urban regions of Western India were evaluated by food frequency questionnaire. RBCMZn was estimated using atomic absorption spectrometry, hemoglobin and serum ceruloplasmin by spectrophotometer. On a sub sample (48 men and 51 women) plasma zinc and SOD were also assessed. Mean RBCMZn was 0.5 +/- 0.1 micromols/g protein with 46% individuals showing zinc deficiency. Mean plasma zinc was 0.98 +/- 0.12 microg/mL with 25% men and 2.5% women having values below normal range. Mean SOD was 0.97 +/- 0.1 (u/mL cells). A significant positive correlation was observed between intakes of green leafy vegetables, other vegetables and milk products with RBCMZn status (p < 0.05). But these were not correlated with plasma zinc (p > 0.2). Cereal and legume intakes were negatively correlated with RBCMZn (p < 0.05) but positively correlated with plasma zinc (p < 0.05) and not correlated with SOD (p > 0.2). Fruit and other vegetable intake were positively correlated with SOD (p < 0.05) alone. Logistic regression analyses revealed that RBCMZn was positively associated with intakes of beta-carotene, zinc and environmental conditions and negatively associated with family size (p < 0.05). Plasma zinc indicated positive association with zinc, thiamin and riboflavin intakes (p < 0.05) and SOD showed negative association with iron and family size. RBCMZn was a more sensitive indicator of long-term zinc status than plasma zinc and SOD. Prominent determinants of zinc status were intakes of beta-carotene and zinc along with environmental conditions and family size.

Center for the Study of Plasma Microturbulence

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parker, Scott E.

We have discovered a possible "natural fueling" mechanism in tokamak fusion reactors using large scale gyrokinetic turbulence simulation. In the presence of a heat flux dominated tokamak plasma, cold ions naturally pinch radially inward. If cold DT fuel is introduced near the edge using shallow pellet injection, the cold fuel will pinch inward, at the expense of hot helium ash going radially outward. By adjusting the cold DT fuel concentration, the core DT density profiles can be maintained. We have also shown that cold source ions from edge recycling of cold neutrals are pinched radially inward. This mechanism may bemore » important for fully understanding the edge pedestal buildup after an ELM crash. Work includes benchmarking the gyrokinetic turbulence codes in the electromagnetic regime. This includes cyclone base case parameters with an increasing plasma beta. The code comparisons include GEM, GYRO and GENE. There is good linear agreement between the codes using the Cyclone base case, but including electromagnetics and scanning the plasma beta. All the codes have difficulty achieving nonlinear saturation as the kinetic ballooning limit is approached. GEM does not saturate well when beta gets above about 1/2 of the ideal ballooning limit. We find that the lack of saturation is due to the long wavelength k{sub y} modes being nonlinearly pumped to high levels. If the fundamental k{sub y} mode is zeroed out, higher values of beta nonlinearly saturate well. Additionally, there have been studies to better understand CTEM nonlinear saturation and the importance of zonal flows. We have continued our investigation of trapped electron mode (TEM) turbulence. More recently, we have focused on the nonlinear saturation of TEM turbulence. An important feature of TEM is that in many parameter regimes, the zonal flow is unimportant. We find that when zonal flows are unimportant, zonal density is the dominant saturation mechanism. We developed a simple theory that agrees with the simulation and predicts zonal density generation and feedback stabilization of the most unstable mode even in the absence of zonal flow. We are using GEM to simulate NSTX discharges. We have also done verification and validation on DIII-D. Good agreement with GYRO and DIII-D flux levels were reported in the core region.« less

Gender impact on first trimester markers in Down syndrome screening.

PubMed

Larsen, Severin Olesen; Wøjdemann, Karen R; Shalmi, Anne-Cathrine; Sundberg, Karin; Christiansen, Michael; Tabor, Ann

2002-12-01

The influence of fetal gender on the level in the first trimester of the serological markers alpha-fetoprotein (AFP), pregnancy-associated plasma protein-A (PAPP-A) and free beta human chorionic gonadotropin (betahCG) and on nuchal translucency is described for 2637 singleton pregnancies with normal outcome. Mean log MoM values for pregnancies with female and male fetuses were calculated using regression of log marker values on gestational age expressed as crown rump length and on maternal weight. A pronounced gender impact was found for free betahCG, being 16% higher for female than for male fetuses. Copyright 2002 John Wiley & Sons, Ltd.

Association of blood eosinophils and plasma periostin with FEV1 response after 3-month inhaled corticosteroid and long-acting beta2-agonist treatment in stable COPD patients

PubMed Central

Park, Hye Yun; Lee, Hyun; Koh, Won-Jung; Kim, Seonwoo; Jeong, Ina; Koo, Hyeon-Kyoung; Kim, Tae-Hyung; Kim, Jin Woo; Kim, Woo Jin; Oh, Yeon-Mok; Sin, Don D; Lim, Seong Yong; Lee, Sang-Do

2016-01-01

Background COPD patients with increased airway eosinophilic inflammation show a favorable response to inhaled corticosteroids (ICS) in combination with a long-acting bronchodilator. Recent studies have demonstrated a significant correlation of sputum eosinophilia with blood eosinophils and periostin. We investigated whether high blood eosinophils and plasma periostin were associated with an improvement in forced expiratory volume in 1 second (FEV1) after 3-month treatment with ICS/long-acting beta2-agonist (LABA) in stable COPD patients. Patients and methods Blood eosinophils and plasma periostin levels were measured in 130 stable COPD subjects selected from the Korean Obstructive Lung Disease cohort. Subjects began a 3-month ICS/LABA treatment after washout period. Results High blood eosinophils (>260/µL, adjusted odds ratio =3.52, P=0.009) and high plasma periostin (>23 ng/mL, adjusted odds ratio =3.52, P=0.013) were significantly associated with FEV1 responders (>12% and 200 mL increase in FEV1 from baseline after treatment). Moreover, the addition of high blood eosinophils to age, baseline positive bronchodilator response, and FEV1 <50% of the predicted value significantly increased the area under the curve for prediction of FEV1 responders (from 0.700 to 0.771; P=0.045). Conclusion High blood eosinophils and high plasma periostin were associated with improved lung function after 3-month ICS/LABA treatment. In particular, high blood eosinophils, in combination with age and baseline lung function parameters, might be a possible biomarker for identification of COPD patients with favorable FEV1 improvement in response to ICS/LABA treatment. PMID:26730185

Association of blood eosinophils and plasma periostin with FEV1 response after 3-month inhaled corticosteroid and long-acting beta2-agonist treatment in stable COPD patients.

PubMed

Park, Hye Yun; Lee, Hyun; Koh, Won-Jung; Kim, Seonwoo; Jeong, Ina; Koo, Hyeon-Kyoung; Kim, Tae-Hyung; Kim, Jin Woo; Kim, Woo Jin; Oh, Yeon-Mok; Sin, Don D; Lim, Seong Yong; Lee, Sang-Do

2016-01-01

COPD patients with increased airway eosinophilic inflammation show a favorable response to inhaled corticosteroids (ICS) in combination with a long-acting bronchodilator. Recent studies have demonstrated a significant correlation of sputum eosinophilia with blood eosinophils and periostin. We investigated whether high blood eosinophils and plasma periostin were associated with an improvement in forced expiratory volume in 1 second (FEV1) after 3-month treatment with ICS/long-acting beta2-agonist (LABA) in stable COPD patients. Blood eosinophils and plasma periostin levels were measured in 130 stable COPD subjects selected from the Korean Obstructive Lung Disease cohort. Subjects began a 3-month ICS/LABA treatment after washout period. High blood eosinophils (>260/µL, adjusted odds ratio =3.52, P=0.009) and high plasma periostin (>23 ng/mL, adjusted odds ratio =3.52, P=0.013) were significantly associated with FEV1 responders (>12% and 200 mL increase in FEV1 from baseline after treatment). Moreover, the addition of high blood eosinophils to age, baseline positive bronchodilator response, and FEV1 <50% of the predicted value significantly increased the area under the curve for prediction of FEV1 responders (from 0.700 to 0.771; P=0.045). High blood eosinophils and high plasma periostin were associated with improved lung function after 3-month ICS/LABA treatment. In particular, high blood eosinophils, in combination with age and baseline lung function parameters, might be a possible biomarker for identification of COPD patients with favorable FEV1 improvement in response to ICS/LABA treatment.

Effect of angiotensin II receptor blocker on plasma levels of TGF-beta 1 and interstitial fibrosis in hypertensive kidney transplant patients.

PubMed

el-Agroudy, Amgad E; Hassan, Nabil A; Foda, Mohamed A; Ismail, Amani M; el-Sawy, Essam A; Mousa, Omar; Ghoneim, Mohamed A

2003-01-01

Transforming growth factor-beta1 (TGF-beta 1) is involved in the pathogenesis of chronic allograft nephropathy after kidney transplantation. The aim of the study was to evaluate the effect of the angiotensin receptor blocker losartan on TGF-beta 1 plasma levels and proteinuria in hypertensive transplant recipients. A total of 162 transplant recipients were included in the study. The patients were randomized into 3 groups: group 1 received losartan; group II received an angiotensin-converting enzyme inhibitor (captopril), and group III received a calcium channel blocker (amlodipine). All the parameters were recorded at the time of therapy initiation and at 1, 4 and 12 weeks and 12 months thereafter. Graft biopsy before the start and at the end of the study was done to evaluate histopathological progression. Blood pressure was controlled in the 3 groups; however, the need for other antihypertensive agents was significant in groups I and II. Treatment with losartan significantly decreased the plasma level of TGF-beta1, 24-hour urinary protein and serum uric acid (p < 0.05). No significant changes were seen in the hemoglobin or serum potassium levels. The rate of histopathological progression was significantly lower in the losartan group. No patient was discharged from the study due to side effects. After transplantation all drugs were able to control blood pressure with good safety and tolerability. The study demonstrates that ARB significantly decreases the plasma levels of TGF-beta1, proteinuria and uric acid. These results could play an important and decisive role in the treatment and prevention of chronic allograft nephropathy. Copyright 2003 S. Karger AG, Basel

Fully relativistic form factor for Thomson scattering.

PubMed

Palastro, J P; Ross, J S; Pollock, B; Divol, L; Froula, D H; Glenzer, S H

2010-03-01

We derive a fully relativistic form factor for Thomson scattering in unmagnetized plasmas valid to all orders in the normalized electron velocity, beta[over ]=v[over ]/c. The form factor is compared to a previously derived expression where the lowest order electron velocity, beta[over], corrections are included [J. Sheffield, (Academic Press, New York, 1975)]. The beta[over ] expansion approach is sufficient for electrostatic waves with small phase velocities such as ion-acoustic waves, but for electron-plasma waves the phase velocities can be near luminal. At high phase velocities, the electron motion acquires relativistic corrections including effective electron mass, relative motion of the electrons and electromagnetic wave, and polarization rotation. These relativistic corrections alter the scattered emission of thermal plasma waves, which manifest as changes in both the peak power and width of the observed Thomson-scattered spectra.

The Properties of Reconnection Current Sheets in GRMHD Simulations of Radiatively Inefficient Accretion Flows

NASA Astrophysics Data System (ADS)

Ball, David; Özel, Feryal; Psaltis, Dimitrios; Chan, Chi-Kwan; Sironi, Lorenzo

2018-02-01

Non-ideal magnetohydrodynamic (MHD) effects may play a significant role in determining the dynamics, thermal properties, and observational signatures of radiatively inefficient accretion flows onto black holes. In particular, particle acceleration during magnetic reconnection events may influence black hole spectra and flaring properties. We use representative general relativistic magnetohydrodynamic (GRMHD) simulations of black hole accretion flows to identify and explore the structures and properties of current sheets as potential sites of magnetic reconnection. In the case of standard and normal evolution (SANE) disks, we find that in the reconnection sites, the plasma beta ranges from 0.1 to 1000, the magnetization ranges from 10‑4 to 1, and the guide fields are weak compared with the reconnecting fields. In magnetically arrested (MAD) disks, we find typical values for plasma beta from 10‑2 to 103, magnetizations from 10‑3 to 10, and typically stronger guide fields, with strengths comparable to or greater than the reconnecting fields. These are critical parameters that govern the electron energy distribution resulting from magnetic reconnection and can be used in the context of plasma simulations to provide microphysics inputs to global simulations. We also find that ample magnetic energy is available in the reconnection regions to power the fluence of bright X-ray flares observed from the black hole in the center of the Milky Way.

Beta-Adrenergic Blockade Does not Prevent Polycythemia or Decrease in Plasma Volume in Men at 4300 m Altitude

NASA Technical Reports Server (NTRS)

Grover, R. F.; Selland, M. A.; McCullough, R. G.; Dahms, T. E.; Wolfel, E. E.; Butterfield, G. E.; Reeves, J. T.; Greenleaf, J. E.

1998-01-01

When humans ascend to high altitude (ALT) their plasma volume (PV) and total blood volume (BV) decrease during the first few days. With continued residence over several weeks, the hypoxia-induced stimulation of erythropoietin increases red cell production which tends to restore BV. Because hypoxia also activates the beta-adrenergic system, which stimulates red blood cell production, we investigated the effect of adrenergic beta-receptor inhibition with propranolol on fluid volumes and the polycythemic response in 11 healthy unacclimatized men (21-33 years old exposed to an ALT of 4300 m (barometric pressure 460 Torr) for 3 weeks on Pikes Peak, Colorado. PV was determined by the Evans blue dye method (PV(sub EB)), BV by the carbon monoxide method (BV(sub CO)), red cell volume (RCV)was calculated from hematocrit (Hct) and BV(sub CO), and serum erythropoietin concentration ([EPO]) and reticulocyte count, were also determined. All determinations were made at sea level and after 9-11 (ALT-10) and 9-20 (ALT-20) days at ALT. At sea level and ALT, six men received propranolol (pro, 240 mg/day), and five received a placebo (pla). Effective beta-blockade did not modify the mean (SE) maximal values of [EPO] [pla: 24.9 (3.5) vs pro: 24.5 (1.5) mU/ml] or reticulocyte count [pla: 2.7 (0.7) vs pro: 2.2 (0.5)%]; nor changes in PV(sub EB)[pla: -15.8 (3.8) vs pro: -19.9 (2.8)%], RCV(sub CO) [pla: +7.0 (6.7) vs pro: +10.1 (6.1)%], or BV(sub CO) [pla: -7.3 (2.3) vs pro: -7.1 (3.9)%]. In the absence of weight loss, a redistribution of body water with no net loss is implied. Hence, activation of the beta-adrenergic system did not appear to affect the hypovolemic or polycythemic responses that occurred during 3 weeks at 4300 m ALT in these subjects.

The relationships between half-life (t1/2) and mean residence time (MRT) in the two-compartment open body model.

PubMed

Sobol, Eyal; Bialer, Meir

2004-05-01

In the one-compartment model following i.v. administration the mean residence time (MRT) of a drug is always greater than its half-life (t(1/2)). However, following i.v. administration, drug plasma concentration (C) versus time (t) is best described by a two-compartment model or a two exponential equation:C=Ae(-alpha t)+Be(-beta t), where A and B are concentration unit-coefficients and alpha and beta are exponential coefficients. The relationships between t(1/2) and MRT in the two-compartment model have not been explored and it is not clear whether in this model too MRT is always greater than t(1/2). In the current paper new equations have been developed that describe the relationships between the terminal t(1/2) (or t(1/2 beta)) and MRT in the two-compartment model following administration of i.v. bolus, i.v. infusion (zero order input) and oral administration (first order input). A critical value (CV) equals to the quotient of (1-ln2) and (1-beta/alpha) (CV=(1-ln2)/(1-beta/alpha)=0.307/(1-beta/alpha)) has been derived and was compared with the fraction (f(1)) of drug elimination or AUC (AUC-area under C vs t curve) associated with the first exponential term of the two-compartment equation (f(1)=A/alpha/AUC). Following i.v. bolus, CV ranges between a minimal value of 0.307 (1-ln2) and infinity. As long as f(1)t(1/2) and vice versa, and when f(1)=CV, then MRT=t(1/2). Following i.v. infusion and oral administration the denominator of the CV equation does not change but its numerator increases to (0.307+beta T/2) (T-infusion duration) and (0.307+beta/ka) (ka-absorption rate constant), respectively. Examples of various drugs are provided. For every drug that after i.v. bolus shows two-compartment disposition kinetics the following conclusions can be drawn (a) When f(1)<0.307, then f(1)t(1/2). (b) When beta/alpha>ln2, then CV>1>f(1) and thus(,) MRT>t(1/2). (c) When ln2>beta/alpha>(ln4-1), then 1>CV>0.5 and thus, in order for t(1/2)>MRT, f(1) has to be greater than its complementary fraction f(2) (f(1)>f(2)). (d) When beta/alpha<(ln4-1), it is possible that t(1/2)>MRT even when f(2)>f(1), as long as f(1)>CV. (e) As beta gets closer to alpha, CV approaches its maximal value (infinity) and therefore, the chances of MRT>t(1/2) are growing. (f) As beta becomes smaller compared with alpha, beta/alpha approaches zero, the denominator approaches unity and consequently, CV gets its minimal value and thus, the chances of t(1/2)>MRT are growing. (g) Following zero and first order input MRT increases compared with i.v. bolus and so does CV and thus, the chances of MRT>t(1/2) are growing. Copyright 2004 John Wiley & Sons, Ltd.

Profile control simulations and experiments on TCV: a controller test environment and results using a model-based predictive controller

NASA Astrophysics Data System (ADS)

Maljaars, E.; Felici, F.; Blanken, T. C.; Galperti, C.; Sauter, O.; de Baar, M. R.; Carpanese, F.; Goodman, T. P.; Kim, D.; Kim, S. H.; Kong, M.; Mavkov, B.; Merle, A.; Moret, J. M.; Nouailletas, R.; Scheffer, M.; Teplukhina, A. A.; Vu, N. M. T.; The EUROfusion MST1-team; The TCV-team

2017-12-01

The successful performance of a model predictive profile controller is demonstrated in simulations and experiments on the TCV tokamak, employing a profile controller test environment. Stable high-performance tokamak operation in hybrid and advanced plasma scenarios requires control over the safety factor profile (q-profile) and kinetic plasma parameters such as the plasma beta. This demands to establish reliable profile control routines in presently operational tokamaks. We present a model predictive profile controller that controls the q-profile and plasma beta using power requests to two clusters of gyrotrons and the plasma current request. The performance of the controller is analyzed in both simulation and TCV L-mode discharges where successful tracking of the estimated inverse q-profile as well as plasma beta is demonstrated under uncertain plasma conditions and the presence of disturbances. The controller exploits the knowledge of the time-varying actuator limits in the actuator input calculation itself such that fast transitions between targets are achieved without overshoot. A software environment is employed to prepare and test this and three other profile controllers in parallel in simulations and experiments on TCV. This set of tools includes the rapid plasma transport simulator RAPTOR and various algorithms to reconstruct the plasma equilibrium and plasma profiles by merging the available measurements with model-based predictions. In this work the estimated q-profile is merely based on RAPTOR model predictions due to the absence of internal current density measurements in TCV. These results encourage to further exploit model predictive profile control in experiments on TCV and other (future) tokamaks.

Real-time diamagnetic flux measurements on ASDEX Upgrade.

PubMed

Giannone, L; Geiger, B; Bilato, R; Maraschek, M; Odstrčil, T; Fischer, R; Fuchs, J C; McCarthy, P J; Mertens, V; Schuhbeck, K H

2016-05-01

Real-time diamagnetic flux measurements are now available on ASDEX Upgrade. In contrast to the majority of diamagnetic flux measurements on other tokamaks, no analog summation of signals is necessary for measuring the change in toroidal flux or for removing contributions arising from unwanted coupling to the plasma and poloidal field coil currents. To achieve the highest possible sensitivity, the diamagnetic measurement and compensation coil integrators are triggered shortly before plasma initiation when the toroidal field coil current is close to its maximum. In this way, the integration time can be chosen to measure only the small changes in flux due to the presence of plasma. Two identical plasma discharges with positive and negative magnetic field have shown that the alignment error with respect to the plasma current is negligible. The measured diamagnetic flux is compared to that predicted by TRANSP simulations. The poloidal beta inferred from the diamagnetic flux measurement is compared to the values calculated from magnetic equilibrium reconstruction codes. The diamagnetic flux measurement and TRANSP simulation can be used together to estimate the coupled power in discharges with dominant ion cyclotron resonance heating.

Pituitary-adrenal hormones and testosterone across the menstrual cycle in women with premenstrual syndrome and controls.

PubMed

Bloch, M; Schmidt, P J; Su, T P; Tobin, M B; Rubinow, D R

1998-06-15

Premenstrual syndrome (PMS) is a cyclic mood disorder, widely believed, yet not conclusively shown, to be of endocrine etiology. This study examines basal levels of several hormones reported, albeit inconsistently, to differ in women with PMS compared with controls. Subjects (10 PMS patients and 10 controls) had their blood drawn for one full menstrual cycle. Subjects' mood and behavioral symptoms were assessed by daily self-ratings and objective ratings. Plasma was assayed for total and free testosterone (T), beta-endorphin (beta-EP), adrenocorticotropic hormone (ACTH), and cortisol. No differences were observed between the PMS and control groups for beta-EP, ACTH, or cortisol. PMS subjects had significantly lower total and free T plasma levels with a blunting of the normal periovulatory peak, a finding that may be epiphenomenal to age. This study does not confirm previous reports of abnormalities in plasma levels of either ACTH or beta-EP in women with PMS; it also fails to replicate a previous observation of high free T levels in women with PMS. These results are not supportive of a primary endocrine abnormality in PMS patients.

Derivatization of beta-dicarbonyl compound with 2,4-dinitrophenylhydrazine to enhance mass spectrometric detection: application in quantitative analysis of houttuynin in human plasma.

PubMed

Duan, Xiaotao; Zhong, Dafang; Chen, Xiaoyan

2008-06-01

Houttuynin (decanoyl acetaldehyde), a beta-dicarbonyl compound, is the major antibacterial constituent in the volatile oil of Houttuynina cordata Thunb. In the present work, detection of houttuynin in human plasma based on the chemical derivatization with 2,4-dinitrophenylhydrazine (DNPH) coupled with liquid chromatography/tandem mass spectrometry was described. The primary reaction products between the beta-dicarbonyl compound and DNPH in aqueous phase were identified as heterocyclic structures, of which the mass spectrometric ionization and fragmentation behavior were characterized with the aid of high-resolution multistage mass spectral analysis. For quantification, houttuynin and internal standard (IS, benzophenone) in plasma were firstly converted to their DNPH derivatives without sample purification, then extracted from human plasma with n-hexane and detected by liquid chromatography tandem mass spectrometry performed in selected reaction monitoring (SRM) mode. This method allowed for a lower limit of quantification (LLOQ) of 1.0 ng/ml using 100-microl plasma. The validation results showed high accuracy (%bias < 2.1) and precision (%CV < 7.2) at broad linear dynamic range (1.0-5000 ng/ml). The simple and quantitative derivatization coupled with tandem mass spectrometric analysis facilitates a sensitive and robust method for the determination of plasma houttuynin in pharmacokinetic studies.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Medvedev, S. Yu., E-mail: medvedev@a5.kiam.ru; Ivanov, A. A., E-mail: aai@a5.kiam.ru; Martynov, A. A., E-mail: martynov@a5.kiam.ru

The influence of current density and pressure gradient profiles in the pedestal on the access to the regimes free from edge localized modes (ELMs) like quiescent H-mode in ITER is investigated. Using the simulator of MHD modes localized near plasma boundary based on the KINX code, calculations of the ELM stability were performed for the ITER plasma in scenarios 2 and 4 under variations of density and temperature profiles with the self-consistent bootstrap current in the pedestal. Low pressure gradient values at the separatrix, the same position of the density and temperature pedestals and high poloidal beta values facilitate reachingmore » high current density in the pedestal and a potential transition into the regime with saturated large scale kink modes. New version of the localized MHD mode simulator allows one to compute the growth rates of ideal peeling-ballooning modes with different toroidal mode numbers and to determine the stability region taking into account diamagnetic stabilization. The edge stability diagrams computations and sensitivity studies of the stability limits to the value of diamagnetic frequency show that diamagnetic stabilization of the modes with high toroidal mode numbers can help to access the quiescent H-mode even with high plasma density but only with low pressure gradient values at the separatrix. The limiting pressure at the top of the pedestal increases for higher plasma density. With flat density profile the access to the quiescent H-mode is closed even with diamagnetic stabilization taken into account, while toroidal mode numbers of the most unstable peeling-ballooning mode decrease from n = 10−40 to n = 3−20.« less

Test of bootstrap current models using high- β p EAST-demonstration plasmas on DIII-D

DOE PAGES

Ren, Qilong; Lao, Lang L.; Garofalo, Andrea M.; ...

2015-01-12

Magnetic measurements together with kinetic profile and motional Stark effect measurements are used in full kinetic equilibrium reconstructions to test the Sauter and NEO bootstrap current models in a DIII-D high-more » $${{\\beta}_{\\text{p}}}$$ EAST-demonstration experiment. This aims at developing on DIII-D a high bootstrap current scenario to be extended on EAST for a demonstration of true steady-state at high performance and uses EAST-similar operational conditions: plasma shape, plasma current, toroidal magnetic field, total heating power and current ramp-up rate. It is found that the large edge bootstrap current in these high-$${{\\beta}_{\\text{p}}}$$ plasmas allows the use of magnetic measurements to clearly distinguish the two bootstrap current models. In these high collisionality and high-$${{\\beta}_{\\text{p}}}$$ plasmas, the Sauter model overpredicts the peak of the edge current density by about 30%, while the first-principle kinetic NEO model is in close agreement with the edge current density of the reconstructed equilibrium. Furthermore, these results are consistent with recent work showing that the Sauter model largely overestimates the edge bootstrap current at high collisionality.« less

Plasma Experiments on an Internal Coil Device with an High Temperature Superconductor

NASA Astrophysics Data System (ADS)

Yuichi, Ogawa; Junji, Morikawa; Kotaro, Ohkuni; Dan, Hori; Shigeo, Yamakosi; Nagato, Yanagi; Toshiyuki, Mito; Masataka, Iwakuma; Toshio, Uede

2003-10-01

An internal coil device would be expected for exploring high beta plasmas based on plasma relaxation process. Prof. A. Hasegawa proposed an advanced fusion reactor with a dipole configuration, and Mahajan and Yoshida developed a new high beta state based on two-fluid relaxation theory. To study these high beta plasmas, we have constructed an internal coil device with a high temperature superconductor. The major radius of the internal coil is 15 cm, and the coil current is 50 kA. Three different types of Ag-sheathed Bi-2223 tapes are employed; i.e., a high critical current tape with a low silver ratio for the main HTS coil, a 0.3wt3atprovided by a GM refrigerator and supplied to the coil through a check valve, and the coil current is directly excited with the external power supply through removable electrodes. It took about 11 hours to cool the coil down to 21 K from the room temperature, and the nominal cable current of 118 A (overall coil current: 50 kA) has been achieved. A decay time constant of the persistent current is a few tens of hours. Plasma experiments in a dipole configuration have been initiated.

Plasma and Salivary Non-Urate Total Antioxidant Capacity Does Not Depend on Dietary Vitamin C, E, or β-Carotene Intake in Older Subjects.

PubMed

Gawron-Skarbek, Anna; Guligowska, Agnieszka; Prymont-Przymińska, Anna; Nowak, Dariusz; Kostka, Tomasz

2018-04-23

The native Total Antioxidant Capacity (TAC) of plasma and saliva is generally determined by uric acid (UA). Several studies have assessed the impact of habitual dietary antioxidative vitamin intake on TAC, but it remains unknown whether it influences Non-Urate Total Antioxidant Capacity (Nu-TAC), i.e., TAC after enzymatic UA elimination. The purpose of this study was to assess whether the intake of antioxidative vitamins C, E, and β-carotene, provided with usual daily food rations, affects plasma and salivary Nu-TAC. The study involved 56 older subjects (aged 66.9 ± 4.3 years), divided into two age- and sex-matched groups: group 1 ( n = 28), with lower combined vitamin C, E, and β-carotene intake, and group 2 ( n = 28), with higher intake. A 24 h dietary recall was obtained from each individual. Nu-TAC was assessed simultaneously with two methods in plasma (Ferric Reducing Ability of Plasma—Nu-FRAP, 2.2-diphenyl-1-picryl-hydrazyl—Nu-DPPH) and in saliva (Nu-FRAS and Nu-DPPHS test). No differences were found in the Nu-TAC parameters between the groups, either in plasma (Nu-FRAP, Nu-DPPH) or in saliva (Nu-FRAS, Nu-DPPHS) ( p > 0.05). No plasma or salivary Nu-TAC indices correlated with dietary vitamin C, E, or β-carotene intake or with other nutrients. Habitual, not extra-supplemented dietary intake does not significantly affect plasma or salivary Nu-TAC.

An adhesion-based method for plasma membrane isolation: evaluating cholesterol extraction from cells and their membranes.

PubMed

Bezrukov, Ludmila; Blank, Paul S; Polozov, Ivan V; Zimmerberg, Joshua

2009-11-15

A method to isolate large quantities of directly accessible plasma membrane from attached cells is presented. The method is based on the adhesion of cells to an adsorbed layer of polylysine on glass plates, followed by hypotonic lysis with ice-cold distilled water and subsequent washing steps. Optimal conditions for coating glass plates and time for cell attachment were established. No additional chemical or mechanical treatments were used. Contamination of the isolated plasma membrane by cell organelles was less than 5%. The method uses inexpensive, commercially available polylysine and reusable glass plates. Plasma membrane preparations can be made in 15 min. Using this method, we determined that methyl-beta-cyclodextrin differentially extracts cholesterol from fibroblast cells and their plasma membranes and that these differences are temperature dependent. Determination of the cholesterol/phospholipid ratio from intact cells does not reflect methyl-beta-cyclodextrin plasma membrane extraction properties.

Modulation of kinetic Alfvén waves in an intermediate low-beta magnetoplasma

NASA Astrophysics Data System (ADS)

Chatterjee, Debjani; Misra, A. P.

2018-05-01

We study the amplitude modulation of nonlinear kinetic Alfvén waves (KAWs) in an intermediate low-beta magnetoplasma. Starting from a set of fluid equations coupled to the Maxwell's equations, we derive a coupled set of nonlinear partial differential equations (PDEs) which govern the evolution of KAW envelopes in the plasma. The modulational instability (MI) of such KAW envelopes is then studied by a nonlinear Schrödinger equation derived from the coupled PDEs. It is shown that the KAWs can evolve into bright envelope solitons or can undergo damping depending on whether the characteristic ratio ( α ) of the Alfvén to ion-acoustic speeds remains above or below a critical value. The parameter α is also found to shift the MI domains around the k x k z plane, where k x ( k z ) is the KAW number perpendicular (parallel) to the external magnetic field. The growth rate of MI, as well as the frequency shift and the energy transfer rate, are obtained and analyzed. The results can be useful for understanding the existence and formation of bright and dark envelope solitons, or damping of KAW envelopes in space plasmas, e.g., interplanetary space, solar winds, etc.

Interplanetary Magnetic Field and Plasma Values Related to Hildcaas Events

NASA Astrophysics Data System (ADS)

Prestes, A.; Serra, S. L.; Vieira, L. A.

2013-05-01

In this work we investigate the interplanetary conditions during the occurrence of 150 HILDCAAs/QUASI-HILDCAAs events occurred between 1998 and 2007. These events were chosen by following strictly the selection criteria for this kind of phenomena and with some criteria flexible. Among the criteria used to characterize events HILDCAAs, the criterion that considers "the AE values never dropped below 200 nT for more than 2 h at a time" was more restrictive, thus only this was modified by changing from 2 to 4 hours the period in which the AE value can't be below 200 nT. In the interplanetary medium, HILDCAAs are associated with high speed solar wind streams, which are frequently embedded with alfvénic fluctuations. At the Sun, these high speed streams are originated in coronal holes. The distribution of events HILDCAAs/quasi-HILDCAAs along the solar cycle shows a pattern of double peak, a less intense around the maximum of the sunspot cycle and other intense in the descending phase, similar to the distribution of low-latitude coronal holes. For each one of the selected events we have found the most probable value of interplanetary magnetic field and plasma. The average values of AE, AU, AL and Dst indices, the density and temperature of the solar wind protons, the solar wind speed, the Bz component of the IMF, the IMF intensity, dynamic pressure and factor beta, among all the 150 events HILDCAAs/quasi-HILDCAAs, were: AE (344.5 ± 65.0 nT), AU (131.0 ± 33.0 nT), AL (-213.7 ± 51.2 nT), Dst (-25.8 ± 12.2 nT), Density (5,0 ± 1,8 cm-3), Temperature (151269.5 ± 48907.7 K), |V| (538.2 ± 83.3 km/s) Bz (-0.71 ± 1.02 nT), |B| (6.7 ± 1.4 nT) pressure (2.6 ± 0.7 nPa) and Beta (0.66 ± 0.27).

Plasma Dopamine-Beta-Hydroxylase as an Index of Peripheral Noradrenergic Activity

DTIC Science & Technology

1981-08-17

Hydroxy lase A c t i v i t y of Monkey Plasma wi th Age. Exper ient ia (Basel ) 1976, 32:834-835 118. Kato, T . ; Waki , Y . ; Nagatsu, T . ; Ohn ish i...Kato , T . ; Waki , Y . ; Nagatsu, T . ; Ohn i sh i , T . : A Simple and Sens i t ive Assay f o r Dopamine-Beta-Hydroxy lase A c t i v i t y by Dual

Parametric Decay Instability and Dissipation of Low-frequency Alfvén Waves in Low-beta Turbulent Plasmas

NASA Astrophysics Data System (ADS)

Fu, Xiangrong; Li, Hui; Guo, Fan; Li, Xiaocan; Roytershteyn, Vadim

2018-03-01

Evolution of the parametric decay instability (PDI) of a circularly polarized Alfvén wave in a turbulent low-beta plasma background is investigated using 3D hybrid simulations. It is shown that the turbulence reduces the growth rate of PDI as compared to the linear theory predictions, but PDI can still exist. Interestingly, the damping rate of the ion acoustic mode (as the product of PDI) is also reduced as compared to the linear Vlasov predictions. Nonetheless, significant heating of ions in the direction parallel to the background magnetic field is observed due to resonant Landau damping of the ion acoustic waves. In low-beta turbulent plasmas, PDI can provide an important channel for energy dissipation of low-frequency Alfvén waves at a scale much larger than the ion kinetic scales, different from the traditional turbulence dissipation models.

Electromagnetic drift waves dispersion for arbitrarily collisional plasmas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Wonjae, E-mail: wol023@ucsd.edu; Krasheninnikov, Sergei I., E-mail: skrash@mae.ucsd.edu; Angus, J. R.

2015-07-15

The impacts of the electromagnetic effects on resistive and collisionless drift waves are studied. A local linear analysis on an electromagnetic drift-kinetic equation with Bhatnagar-Gross-Krook-like collision operator demonstrates that the model is valid for describing linear growth rates of drift wave instabilities in a wide range of plasma parameters showing convergence to reference models for limiting cases. The wave-particle interactions drive collisionless drift-Alfvén wave instability in low collisionality and high beta plasma regime. The Landau resonance effects not only excite collisionless drift wave modes but also suppress high frequency electron inertia modes observed from an electromagnetic fluid model in collisionlessmore » and low beta regime. Considering ion temperature effects, it is found that the impact of finite Larmor radius effects significantly reduces the growth rate of the drift-Alfvén wave instability with synergistic effects of high beta stabilization and Landau resonance.« less

Differential expression of largemouth bass (Micropterus salmoides) estrogen receptor isotypes alpha, beta, and gamma by estradiol.

PubMed

Sabo-Attwood, Tara; Kroll, Kevin J; Denslow, Nancy D

2004-04-15

The expression levels of three estrogen receptor (ER) isotypes alpha, beta, and gamma were quantified in female largemouth bass (Micropterus salmoides) (LMB) liver, ovary, brain, and pituitary tissues. ER alpha and beta expression predominated in the liver, while ERs beta and gamma predominated in the other tissues. Temporally in females, ER alpha was highly up-regulated, ER gamma was slightly up-regulated, and ER beta levels remained unchanged in the liver when plasma 17-beta estradiol (E2) and vitellogenin (Vtg) levels were elevated in the spring. In ovarian tissue from these same fish, all three ERs were maximally expressed in the fall, during early oocyte development and prior to peak plasma E2 levels. When males were injected with E2, ER alpha was highly inducible, ER gamma was moderately up-regulated, and ER beta levels were not affected. None of the ER isotypes were induced by E2 in gonadal tissues. These results combined suggest that the ERs themselves are not regulated in the same manner by E2, and furthermore, do not contribute equally to the transcriptional regulation of genes involved in fish reproduction such as Vtg.

Endocrinological effects of single daily ketoconazole administration in male beagle dogs.

PubMed

De Coster, R; Beerens, D; Dom, J; Willemsens, G

1984-10-01

Some endocrinological effects of single daily oral administration of 150 mg ketoconazole for 15 days were investigated in 4 male beagle dogs. Plasma testosterone fell markedly within 3-4 h and then progressively returned to control concentrations by 10 h after drug administration. On the other hand, plasma 17 alpha-hydroxyprogesterone, progesterone and 17 alpha, 20 alpha-dihydroxyprogesterone increased within 3-10 h before returning to basal values after 24 h. Plasma LH did not rise significantly though some high individual levels were noted. Plasma cortisol and oestradiol-17 alpha levels were not significantly modified by the treatment. These results confirm that a high therapeutic dose of ketoconazole, given orally once a day, transiently inhibits in vivo the 17-20 lyase enzyme of the testis, without modifying basal cortisol and oestradiol-17 beta plasma concentrations and that enzymatic inhibition still occurs after daily treatment for up to 2 weeks but remains transient and parallels the resorption profile of the drug so that normal plasma testosterone levels are observed from 10 to 24 h after drug intake. However, permanent inhibition of androgen biosynthesis might be obtained by the administration of high doses of ketoconazole given several times a day.

Inactivation of the Hutchinson strain of non-A, non-B hepatitis virus by combined use of beta-propiolactone and ultraviolet irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prince, A.M.; Stephan, W.; Dichtelmueller, H.B.

1985-06-01

A beta-propiolactone/ultraviolet irradiation procedure (beta PL/UV) has been evaluated for its ability to inactivate 30,000 chimpanzee infectious doses of the Hutchinson strain of non-A, non-B (NANB) virus. The chimpanzees were inoculated with plasma to which this dose of the titrated virus had been added prior to application of the beta PL/UV process in accordance with a procedure used for licensed blood derivatives in Germany. Neither animal developed hepatitis. When subsequently challenged with the same contaminated plasma, which had not been sterilized, both animals promptly developed typical NANB hepatitis. This study extends the high (approximately 10(7)-fold) process efficiency of the betamore » PL/UV procedure previously reported for hepatitis B virus to a blood-borne NANB virus.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jung, Young-Dae

The plasmon and screening effects on the entanglement fidelity for the elastic electron-ion collision are investigated in hot quantum plasmas. The partial wave analysis and effective interaction including the plasmon couplings are employed to obtain the entanglement fidelity function in hot quantum plasmas. It is shown that the plasmon effect enhances the entanglement fidelity in quantum plasmas for 0<{beta}({identical_to}({Dirac_h}/2{pi}){omega}{sub p}/k{sub B}T)<0.8 and, however, suppresses the entanglement fidelity for 0.8<{beta}<1, where {omega}{sub p} is the plasmon frequency, k{sub B} is the Boltzmann constant, and T is the plasma temperature. It is also found that the entanglement fidelity decreases with increasing Debyemore » length and collision energy.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

A Kolyada; C Lee; A De Biasio

{beta}2GPI is a major antigen for autoantibodies associated with antiphospholipid syndrome (APS), an autoimmune disease characterized by thrombosis and recurrent pregnancy loss. Only the dimeric form of {beta}2GPI generated by anti-{beta}2GPI antibodies is pathologically important, in contrast to monomeric {beta}2GPI which is abundant in plasma. We created a dimeric inhibitor, A1-A1, to selectively target {beta}2GPI in {beta}2GPI/antibody complexes. To make this inhibitor, we isolated the first ligand-binding module from ApoER2 (A1) and connected two A1 modules with a flexible linker. A1-A1 interferes with two pathologically important interactions in APS, the binding of {beta}2GPI/antibody complexes with anionic phospholipids and ApoER2. Wemore » compared the efficiency of A1-A1 to monomeric A1 for inhibition of the binding of {beta}2GPI/antibody complexes to anionic phospholipids. We tested the inhibition of {beta}2GPI present in human serum, {beta}2GPI purified from human plasma and the individual domain V of {beta}2GPI. We demonstrated that when {beta}2GPI/antibody complexes are formed, A1-A1 is much more effective than A1 in inhibition of the binding of {beta}2GPI to cardiolipin, regardless of the source of {beta}2GPI. Similarly, A1-A1 strongly inhibits the binding of dimerized domain V of {beta}2GPI to cardiolipin compared to the monomeric A1 inhibitor. In the absence of anti-{beta}2GPI antibodies, both A1-A1 and A1 only weakly inhibit the binding of pathologically inactive monomeric {beta}2GPI to cardiolipin. Our results suggest that the approach of using a dimeric inhibitor to block {beta}2GPI in the pathological multivalent {beta}2GPI/antibody complexes holds significant promise. The novel inhibitor A1-A1 may be a starting point in the development of an effective therapeutic for antiphospholipid syndrome.« less

Transport and stability analyses supporting disruption prediction in high beta KSTAR plasmas

NASA Astrophysics Data System (ADS)

Ahn, J.-H.; Sabbagh, S. A.; Park, Y. S.; Berkery, J. W.; Jiang, Y.; Riquezes, J.; Lee, H. H.; Terzolo, L.; Scott, S. D.; Wang, Z.; Glasser, A. H.

2017-10-01

KSTAR plasmas have reached high stability parameters in dedicated experiments, with normalized beta βN exceeding 4.3 at relatively low plasma internal inductance li (βN/li>6). Transport and stability analyses have begun on these plasmas to best understand a disruption-free path toward the design target of βN = 5 while aiming to maximize the non-inductive fraction of these plasmas. Initial analysis using the TRANSP code indicates that the non-inductive current fraction in these plasmas has exceeded 50 percent. The advent of KSTAR kinetic equilibrium reconstructions now allows more accurate computation of the MHD stability of these plasmas. Attention is placed on code validation of mode stability using the PEST-3 and resistive DCON codes. Initial evaluation of these analyses for disruption prediction is made using the disruption event characterization and forecasting (DECAF) code. The present global mode kinetic stability model in DECAF developed for low aspect ratio plasmas is evaluated to determine modifications required for successful disruption prediction of KSTAR plasmas. Work supported by U.S. DoE under contract DE-SC0016614.

Arylesterase activities in the plasma of rats, rabbits and humans on low- and high-cholesterol diets.

PubMed

Beynen, A C; Weinans, G J; Katan, M B

1984-01-01

Arylesterase activities were measured with beta-naphthylpropionate and/or alpha-naphthylacetate as substrate in the plasma of rats, rabbits and humans on low- and high-cholesterol diets. The plasma esterase activities measured with alpha-naphthylacetate were similar in rats, rabbits and humans. With beta-naphthylpropionate as a substrate, rabbits were found to have a markedly higher esterase activity than rats and humans. Basal plasma esterase activity was significantly higher in an inbred rat strain which is hyporesponsive to dietary cholesterol than in a hyperresponsive strain. In rats, but not in humans and rabbits, plasma esterase activity was significantly increased by a high-cholesterol diet. In individual humans and random-bred rabbits and rats there was no association between initial plasma total esterase activity and the subsequent plasma cholesterol response to cholesterol feeding. We suggest that arylesterases are associated with cholesterol metabolism and with the response to dietary cholesterol in rats; evidence for such a role in rabbits and humans is, however, inconclusive.

Genetics Home Reference: dopamine beta-hydroxylase deficiency

MedlinePlus

... deficiency Sources for This Page Cubells JF, Zabetian CP. Human genetics of plasma dopamine beta-hydroxylase activity: ... 16. Review. Citation on PubMed Kim CH, Zabetian CP, Cubells JF, Cho S, Biaggioni I, Cohen BM, Robertson ...

Inverted Temperature Loops in The Quiet Corona: Properties and Physical Origin

NASA Astrophysics Data System (ADS)

Huang, Z.; van der Holst, B.; Frazin, R. A.; Nuevo, F.; Vásquez, A. M.; Manchester, W.; Sokolov, I.; Gombosi, T. I.

2013-12-01

Huang et al. 2012 revealed the existence of inverted temperature ("down") loops, in which temperature decreases with height, as well as the usual ("up") loops, in which the temperature increases with height, in the quiet solar Corona. It was shown that the "down" loops are mostly located at low latitudes and "up" loops most often appear in high latitudes. A recent study by Nuevo et al. 2013 confirmed this discovery and further showed that the "down" loop population is greatest at solar minimum; and strongly decreases with solar activity. Moreover, the "down" loops were found to be associated with values of the plasma beta greater than about unity, while the "up" loops were associated with much smaller values of beta. Here, we review the properties of "up" and "down" loops, and employ a state-of-the-art global MHD model to understand the physics of these loops as well as to investigate their thermodynamic stability. The 3D MHD model uses a phenomenological wave dissipation model based on wave reflection (proportional to the Alfvén speed gradients) and turbulent dissipation.

Advanced ECCD based NTM control in closed-loop operation at ASDEX Upgrade (AUG)

NASA Astrophysics Data System (ADS)

Reich, Matthias; Barrera-Orte, Laura; Behler, Karl; Bock, Alexander; Giannone, Louis; Maraschek, Marc; Poli, Emanuele; Rapson, Chris; Stober, Jörg; Treutterer, Wolfgang

2012-10-01

In high performance plasmas, Neoclassical Tearing Modes (NTMs) are regularly observed at reactor-grade beta-values. They limit the achievable normalized beta, which is undesirable because fusion performance scales as beta squared. The method of choice for controlling and avoiding NTMs at AUG is the deposition of ECCD inside the magnetic island for stabilization in real-time (rt). Our approach to tackling such complex control problems using real-time diagnostics allows rigorous optimization of all subsystems. Recent progress in rt-equilibrium reconstruction (< 3.5 ms), rt-localization of NTMs (< 8 ms) and rt beam tracing (< 25 ms) allows closed-loop feedback operation using multiple movable mirrors as the ECCD deposition actuator. The rt-equilibrium uses function parametrization or a fast Grad-Shafranov solver with an option to include rt-MSE measurements. The island localization is based on a correlation of ECE and filtered Mirnov signals. The rt beam-tracing module provides deposition locations and their derivative versus actuator position of multiple gyrotrons. The ``MHD controller'' finally drives the actuators. Results utilizing closed-loop operation with multiple gyrotrons and their effect on NTMs are shown.

Plasma concentrations of 15-keto-13,14-dihydro-PGF-2 alpha, oestrone sulphate, oestradiol-17 beta and progesterone in pregnant guinea-pigs treated with polychlorinated biphenyls.

PubMed

Lundkvist, U; Kindahl, H

1989-09-01

Guinea-pigs treated by gavage with a total dose of 100 mg polychlorinated biphenyls (PCB: Clophen A50) during Days 17-61 of gestation had higher plasma concentrations of 15-keto-13,14-dihydroprostaglandin F-2 alpha, oestrone sulphate and oestradiol-17 beta during the later stages of gestation than did vehicle-treated guinea-pigs. No changes were observed in plasma progesterone concentrations. Our results provide no support for the hypothesis that an enzyme-induced decrease in progesterone concentrations is the main cause of the fetal death observed in PCB-treated guinea-pigs.

An energy confinement study of the MST (Madison Symmetric Torus) reversed field pinch using a Thomson scattering diagnostic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Den Hartog, D.J.

1989-11-01

Thomson scattering measurements of the central electron temperature and density during the plasma current peak have been performed on the MST Reversed Field Pinch (RFP). This Thomson scattering diagnostic was calibrated for absolute electron density measurements. These measurements of T{sub e} and n{sub e}, when combined with profile assumptions, were used to calculate estimates of energy confinement time ({tau}{sub E}) and poloidal beta ({beta}{sub {theta}}). A standard discharge with I{sub p} {approx} 400 kA, F {approx} {minus}0.1, and {theta} {approx} 1.6 typically exhibited T{sub e} {approx} 275 eV, n{sub e} {approx} 2.0 {times} 10{sup 13} cm{sup {minus}3}, {tau}{sub E} {le}more » 1 ms, and {beta}{sub {theta}} {le} 8%. The results of a limited plasma current scaling study did not indicate a strong scaling of T{sub e} or {tau}{sub E} with I{sub p}. The Thomson scattering diagnostic was used in conjunction with a bolometer, VUV radiation monitor, and edge magnetic coils to study the loss of energy from the plasma. Results indicate that thermal transport from stochastic magnetic fields, particle loss, and radiation are important energy loss processes. The experiments done for this study included an F-scan, a paddle limiter insertion series, and an argon doping series. The plasma maintained a constant {beta}{tau} during these perturbation experiments, suggesting that increases in one energy loss channel are compensated by drops in other channels and increases in input power to the plasma.« less

An energy-confinement study of the MST reversed-field pinch using a Thomson-scattering diagnostic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Den Hartog, D.J.

1989-01-01

Thomson scattering measurements of the central electron temperature and density during the plasma current peak have been performed on the MST Reversed Field Pinch (RFP). This Thomson scattering diagnostic was calibrated for absolute electron density measurements. These measurements of T{sub e} and n{sub e}, when combined with profile assumptions, were used to calculate estimates of energy confinement time ({tau}{sub E}) and poloidal beta ({beta}{sub {theta}}). A standard discharge with I{sub p} {approx} 400 kA, F {approx} {minus}0.1, and {theta} {approx} 1.6 typically exhibited T{sub e} {approx} 275 eV, n{sub e} {approx} 2.0 {times} 10{sup 13} cm{sup {minus}3}, {tau}{sub E}

Activation of the novel estrogen receptor G protein-coupled receptor 30 (GPR30) at the plasma membrane.

PubMed

Filardo, E; Quinn, J; Pang, Y; Graeber, C; Shaw, S; Dong, J; Thomas, P

2007-07-01

G protein-coupled receptor 30 (GPR30), a seven-transmembrane receptor (7TMR), is associated with rapid estrogen-dependent, G protein signaling and specific estrogen binding. At present, the subcellular site of GPR30 action is unclear. Previous studies using antibodies and fluorochrome-labeled estradiol (E2) have failed to detect GPR30 on the cell surface, suggesting that GPR30 may function uniquely among 7TMRs as an intracellular receptor. Here, we show that detectable expression of GPR30 on the surface of transfected HEK-293 cells can be selected by fluorescence-activated cell sorting. Expression of GPR30 on the cell surface was confirmed by confocal microscopy using the lectin concanavalin A as a plasma membrane marker. Stimulation of GPR30-expressing HEK-293 cells with 17beta-E2 caused sequestration of GPR30 from the cell surface and resulted in its codistribution with clathrin and mobilization of intracellular calcium stores. Evidence that GPR30 signals from the cell surface was obtained from experiments demonstrating that the cell-impermeable E2-protein conjugates E2-BSA and E2-horseradish peroxidase promote GPR30-dependent elevation of intracellular cAMP concentrations. Subcellular fractionation studies further support the plasma membrane as a site of GPR30 action with specific [3H]17beta-E2 binding and G protein activation associated with plasma membrane but not microsomal, or other fractions, prepared from HEK-293 or SKBR3 breast cancer cells. These results suggest that GPR30, like other 7TMRs, functions as a plasma membrane receptor.

FIXED DOSE COMBINATIONS WITH SELECTIVE BETA-BLOCKERS: QUANTITATIVE DETERMINATION IN BIOLOGICAL FLUIDS.

PubMed

Mahu, Ştefania Corina; Hăncianu, Monica; Agoroaei, Luminiţa; Grigoriu, Ioana Cezara; Strugaru, Anca Monica; Butnaru, Elena

2015-01-01

Hypertension is one of the most common causes of death, a complex and incompletely controlled disease for millions of patients. Metoprolol, bisoprolol, nebivolol and atenolol are selective beta-blockers frequently used in the management of arterial hypertension, alone or in fixed combination with other substances. This study presents the most used analytical methods for simultaneous determination in biological fluids of fixed combinations containing selective beta-blockers. Articles in Pub-Med, Science Direct and Wiley Journals databases published between years 2004-2014 were reviewed. Methods such as liquid chromatography--mass spectrometry--mass spectrometry (LC-MS/MS), high performance liquid chromatography (HPLC) or high performance liquid chromatography--mass spectrometry (HPLC-MS) were used for determination of fixed combination with beta-blockers in human plasma, rat plasma and human breast milk. LC-MS/MS method was used for simultaneous determination of fixed combinations of metoprolol with simvastatin, hydrochlorothiazide or ramipril, combinations of nebivolol and valsartan, or atenolol and amlodipine. Biological samples were processed by protein precipitation techniques or by liquid-liquid extraction. For the determination of fixed dose combinations of felodipine and metoprolol in rat plasma liquid chromatography--electrospray ionization--mass spectrometry (LC-ESI-MS/MS) was applied, using phenacetin as internal standard. HPLC-MS method was applied for the determination of bisoprolol and hydrochlorothiazide in human plasma. For the determination of atenolol and chlorthalidone from human breast milk and human plasma the HPLC method was used. The analytical methods were validated according to the specialized guidelines, and were applied to biological samples, thing that confirms the permanent concern of researchers in this field.

Beneficial effect of 17{beta}-estradiol on hyperglycemia and islet {beta}-cell functions in a streptozotocin-induced diabetic rat model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamabe, Noriko; Kang, Ki Sung; Zhu Baoting, E-mail: BTZhu@kumc.ed

2010-11-15

The modulating effect of estrogen on glucose homeostasis remains a controversial issue at present. In this study, we sought to determine the beneficial effect of 17{beta}-estradiol (E{sub 2}) on hyperglycemia and islet {beta}-cell functions in streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley rats were injected i.p. with STZ to induce a relatively mild diabetic condition. The rats were then treated with E{sub 2} orally at 500 {mu}g/kg body weight/day for 15 days to evaluate the modulating effect on hyperglycemia, insulin secretion, and islet {beta}-cell proliferation. E{sub 2} administration for 10 days significantly lowered plasma glucose levels, increased plasma insulin levels, andmore » improved glucose tolerance by attenuating insulin response to oral glucose loading. These beneficial effects of E{sub 2} were accompanied by increases in islet number and volume, rate of islet cell proliferation, and the amount of insulin secreted. The growth-stimulatory effect of E{sub 2} on islet cells was linked to the functions of the estrogen receptor {alpha}. Notably, these protective effects of E{sub 2} on diabetic conditions were basically not observed when the STZ-treated rats had a more severe degree of islet damage and hyperglycemia. Taken together, we conclude that E{sub 2} can promote the regeneration of damaged pancreatic islets by stimulating {beta}-cell proliferation in diabetic rats, and this effect is accompanied by improvements in glucose tolerance and a decrease in plasma glucose levels. These findings suggest that oral administration of E{sub 2} may be beneficial in diabetic patients with an accelerated loss of islet {beta}-cells.« less

Rapid determination of some beta-blockers in complicated matrices by tandem dispersive liquid-liquid microextraction followed by high performance liquid chromatography.

PubMed

Hemmati, Maryam; Asghari, Alireza; Bazregar, Mohammad; Rajabi, Maryam

2016-11-01

In this research work, an efficient tandem dispersive liquid-liquid microextraction (TDLLME) procedure coupled with high performance liquid chromatography-ultraviolet detection (HPLC-UV) was successfully applied for the determination of beta-blockers in human plasma and pharmaceutical wastewater samples. High clean-up and preconcentration factor are easily and rapidly feasible via this novel, cheap, and safe microextraction method, leading to high quality experimental data. It consists of two sequential dispersive liquid-liquid microextraction methods, accomplished via air/ultrasonic agitation and air agitation, respectively. In order to enrich the optimal values for the mentioned procedures, the Box-Behnken design (BBD) combined with the desirability function (DF) was used. The optimum values were found to be 11.0 % (w/v) of the salt amount, an initial pH value of 12.0, 103 μL of organic extractant phase, and 45 μL of aqueous extractant phase with pH value of 2.0, resulted in reasonable recovery percentages with a logical desirability. Under optimal experimental conditions, good linear ranges (3-2000 ng mL -1 for metoprolol and 2.5-2500 ng mL -1 for propranolol with the correlation of determinations (R 2 s) higher than 0.99) and low limits of detection (0.8 and 1.0 ng mL -1 for propranolol and metoprolol, respectively) were obtainable. Also, TDLLME-HPLC-UV provided good proper repeatabilities (relative standard deviations (RSDs) below 5.7 %, n = 3) and high enrichment factors (EFs) of 75-100. Graphical abstract TDLLME of beta-blockers from complicated matrices.

A Model for Straight and Helical Solar Jets: II. Parametric Study of the Plasma Beta

NASA Technical Reports Server (NTRS)

Pariat, E.; Dalmasse, K.; DeVore, C. R.; Antiochos, S. K.; Karpen, J. T.

2016-01-01

Context. Jets are dynamic, impulsive, well-collimated plasma events that develop at many different scales and in different layers of the solar atmosphere. Aims. Jets are believed to be induced by magnetic reconnection, a process central to many astrophysical phenomena. Within the solar atmosphere, jet-like events develop in many different environments, e.g. in the vicinity of active regions as well as in coronal holes, and at various scales, from small photospheric spicules to large coronal jets. In all these events, signatures of helical structure and/or twisting/rotating motions are regularly observed. The present study aims to establish that a single model can generally reproduce the observed properties of these jet-like events. Methods. In this study, using our state-of-the-art numerical solver ARMS, we present a parametric study of a numerical tridimensional magnetohydrodynamic (MHD) model of solar jet-like events. Within the MHD paradigm, we study the impact of varying the atmospheric plasma beta on the generation and properties of solar-like jets. Results. The parametric study validates our model of jets for plasma beta ranging from 10(sup 3) to 1, typical of the different layers and magnetic environments of the solar atmosphere. Our model of jets can robustly explain the generation of helical solar jet-like events at various beta less than or equal to 1. We show that the plasma beta modifies the morphology of the helical jet, explaining the different observed shapes of jets at different scales and in different layers of the solar atmosphere. Conclusions. Our results allow us to understand the energisation, triggering, and driving processes of jet-like events. Our model allows us to make predictions of the impulsiveness and energetics of jets as determined by the surrounding environment, as well as the morphological properties of the resulting jets.

In vitro production of beta-very low density lipoproteins and small, dense low density lipoproteins in mildly hypertriglyceridemic plasma: role of activities of lecithin:cholester acyltransferase, cholesterylester transfer proteins and lipoprotein lipase.

PubMed

Chung, B H; Segrest, J P; Franklin, F

1998-12-01

As a model for the formation of beta-very low density lipoproteins (VLDL) and small, dense LDL by the intraplasma metabolic activities in vivo, lipoproteins in fresh plasma were interacted in vitro with endogenous lecithin:cholesterol acyltransferase (LCAT) and cholesterylester transfer proteins (CETP) and subsequently with purified lipoprotein lipase (LpL). The LCAT and CETP reactions in a mildly hypertriglyceridemic (HTG) plasma at 37 degrees C for 18 h resulted in (1) esterification of about 45% plasma unesterified cholesterol (UC), (2) a marked increase in cholesterylester (CE) (+129%) and a decrease in triglyceride (TG) (-45%) in VLDL, and (3) a marked increase of TG (+ 341%) with a small net decrease of CE (-3.6%) in LDL, causing a significant alteration in the TG/CE of VLDL (from 8.0 to 1.9) and of LDL (from 0.20 to 0.93). The LDL in LCAT and CETP-reacted plasma is larger and more buoyant than that in control plasma. In vitro lipolysis of control and LCAT and CETP-reacted plasma by LpL, which hydrolyzed >90% of VLDL-TG and about 50-60% of LDL-TG, converted most of VLDL in control plasma (>85%) but less than half (40%) of VLDL in LCAT and CETP-reacted plasma into the IDL-LDL density fraction and transformed the large, buoyant LDL in the LCAT and CETP-reacted plasma into particles smaller and denser than those in the control plasma. The remnants that accumulated in the VLDL density region of the postlipolysis LCAT and CETP-reacted plasma contained apo B-100 and E but little or no detectable apo Cs and consisted of particles having pre-beta and beta-electrophoretic mobilities. The inhibition of LCAT during incubation of plasma, which lessened the extent of alteration in VLDL and LDL core lipids, increased the extent of lipolytic removal of VLDL from the VLDL density region but lowered the extent of alteration in the size and density of LDL. The LCAT, CETP and/or LpL-mediated alterations in the density of LDL in normolipidemic fasting plasma were less pronounced than that in mildly HTG plasma, but they became highly pronounced upon increase of its TG-rich lipoprotein level by the addition of preisolated VLDL or by the induction of postprandial lipemia. Although the effect of LCAT, CETP and LpL reactions in non-circulating plasma in vitro may be different from that in vivo, the above data suggests that the plasma TG-rich lipoprotein level and the extent of intraplasma LCAT, CETP, LpL and likely hepatic lipase (HL) reactions in vivo may play a role in determining the LDL phenotype.

Approach to ignition of tokamak reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sigmar, D.J.

1981-02-01

Recent transport modeling results for JET, INTOR, and ETF are reviewed and analyzed with respect to existing uncertainties in the underlying physics, the self-consistency of the very large numerical codes, and the margin for ignition. The codes show ignition to occur in ETF/INTOR-sized machines if empirical scaling can be extrapolated to ion temperatures (and beta values) much higher than those presently achieved, if there is no significant impurity accumulation over the first 7 s, and if the known ideal and resistive MHD instabilities remain controllable for the evolving plasma profiles during ignition startup.

Multi-Wavelength Imaging of Solar Plasma - High-Beta Disruption Model of Solar Flares -

NASA Astrophysics Data System (ADS)

Shibasaki, Kiyoto

Solar atmosphere is filled with plasma and magnetic field. Activities in the atmosphere are due to plasma instabilities in the magnetic field. To understand the physical mechanisms of activities / instabilities, it is necessary to know the physical conditions of magnetized plasma, such as temperature, density, magnetic field, and their spatial structures and temporal developments. Multi-wavelength imaging is essential for this purpose. Imaging observations of the Sun at microwave, X-ray, EUV and optical ranges are routinely going on. Due to free exchange of original data among solar physics and related field communities, we can easily combine images covering wide range of spectrum. Even under such circumstances, we still do not understand the cause of activities in the solar atmosphere well. The current standard model of solar activities is based on magnetic reconnection: release of stored magnetic energy by reconnection is the cause of solar activities on the Sun such as solar flares. However, recent X-ray, EUV and microwave observations with high spatial and temporal resolution show that dense plasma is involved in activities from the beginning. Based on these observations, I propose a high-beta model of solar activities, which is very similar to high-beta disruptions in magnetically confined fusion experiments.

MHD stability analysis and global mode identification preparing for high beta operation in KSTAR

NASA Astrophysics Data System (ADS)

Park, Y. S.; Sabbagh, S. A.; Berkery, J. W.; Jiang, Y.; Ahn, J. H.; Han, H. S.; Bak, J. G.; Park, B. H.; Jeon, Y. M.; Kim, J.; Hahn, S. H.; Lee, J. H.; Ko, J. S.; in, Y. K.; Yoon, S. W.; Oh, Y. K.; Wang, Z.; Glasser, A. H.

2017-10-01

H-mode plasma operation in KSTAR has surpassed the computed n = 1 ideal no-wall stability limit in discharges exceeding several seconds in duration. The achieved high normalized beta plasmas are presently limited by resistive tearing instabilities rather than global kink/ballooning or RWMs. The ideal and resistive stability of these plasmas is examined by using different physics models. The observed m/ n = 2/1 tearing stability is computed by using the M3D-C1 code, and by the resistive DCON code. The global MHD stability modified by kinetic effects is examined using the MISK code. Results from the analysis explain the stabilization of the plasma above the ideal MHD no-wall limit. Equilibrium reconstructions used include the measured kinetic profiles and MSE data. In preparation for plasma operation at higher beta utilizing the planned second NBI system, three sets of 3D magnetic field sensors have been installed and will be used for RWM active feedback control. To accurately determine the dominant n-component produced by low frequency unstable RWMs, an algorithm has been developed that includes magnetic sensor compensation of the prompt applied field and the field from the induced current on the passive conductors. Supported by US DOE Contracts DE-FG02-99ER54524 and DE-SC0016614.

Temperature anisotropy instabilities stimulated by the interplay of the core and halo electrons in space plasmas

NASA Astrophysics Data System (ADS)

Lazar, M.; Shaaban, S. M.; Fichtner, H.; Poedts, S.

2018-02-01

Two central components are revealed by electron velocity distributions measured in space plasmas, a thermal bi-Maxwellian core and a bi-Kappa suprathermal halo. A new kinetic approach is proposed to characterize the temperature anisotropy instabilities driven by the interplay of core and halo electrons. Suggested by the observations in the solar wind, direct correlations of these two populations are introduced as co-variations of the key parameters, e.g., densities, temperature anisotropies, and (parallel) plasma betas. The approach involving correlations enables the instability characterization in terms of either the core or halo parameters and a comparative analysis to depict mutual effects. In the present paper, the instability conditions are described for an extended range of plasma beta parameters, making the new dual approach relevant for a wide variety of space plasmas, including the solar wind and planetary magnetospheres.

High-performance liquid chromatographic determination of the beta2-selective adrenergic agonist fenoterol in human plasma after fluorescence derivatization.

PubMed

Kramer, S; Blaschke, G

2001-02-10

A sensitive high-performance liquid chromatographic method has been developed for the determination of the beta2-selective adrenergic agonist fenoterol in human plasma. To improve the sensitivity of the method, fenoterol was derivatized with N-(chloroformyl)-carbazole prior to HPLC analysis yielding highly fluorescent derivatives. The assay involves protein precipitation with acetonitrile, liquid-liquid-extraction of fenoterol from plasma with isobutanol under alkaline conditions followed by derivatization with N-(chloroformyl)-carbazole. Reversed-phase liquid chromatographic determination of the fenoterol derivative was performed using a column-switching system consisting of a LiChrospher 100 RP 18 and a LiChrospher RP-Select B column with acetonitrile, methanol and water as mobile phase. The limit of quantitation in human plasma was 376 pg fenoterol/ml. The method was successfully applied for the assay of fenoterol in patient plasma.

Hemodynamics, renal function, plasma renin, and aldosterone in man after 5 to 14 days of bedrest

NASA Technical Reports Server (NTRS)

Melada, G. A.; Goldman, R. H.; Luetscher, J. A.; Zager, P. G.

1975-01-01

Continuous bedrest for 5 to 14 days had no significant effect on resting heart rate, blood pressure, or cardiac output in six normal men. Head-up tilt induced greater tachycardia in 5 of 6 patients after bed rest than in the control period. Propranolol diminished both tachycardia and the incidence of hypotension and faintness in upright posture. Plasma volume fell, extracellular fluid volume increased, and plasma renin activity was significantly elevated following bedrest. Unusually large increases in plasma renin followed head-up tilt or administration of isoproterenol during bedrest and after resuming normal activity. During bedrest, plasma aldosterone was often increased in the early morning. It is concluded that after bedrest, upright posture evokes strong beta-adrenergic activity as well as exaggerated metabolic and circulatory responses which can be reduced or abolished by the beta-adrenergic blocker, propranolol.

Dissipation of Alfven Waves at Fluid Scale through Parametric Decay Instabilities in Low-beta Turbulent Plasma

NASA Astrophysics Data System (ADS)

Fu, X.; Li, H.; Guo, F.; Li, X.; Roytershteyn, V.

2017-12-01

The solar wind is a turbulent magnetized plasma extending from the upper atmosphere of the sun to the edge of the heliosphere. It carries charged particles and magnetic fields originated from the Sun, which have great impact on the geomagnetic environment and human activities in space. In such a magnetized plasma, Alfven waves play a crucial role in carrying energy from the surface of the Sun, injecting into the solar wind and establishing power-law spectra through turbulent energy cascades. On the other hand, in compressible plasmas large amplitude Alfven waves are subject to a parametric decay instability (PDI) which converts an Alfven wave to another counter-propagating Alfven wave and an ion acoustic wave (slow mode). The counter-propagating Alfven wave provides an important ingredient for turbulent cascade, and the slow-mode wave provides a channel for solar wind heating in a spatial scale much larger than ion kinetic scales. Growth and saturation of PDI in quiet plasma have been intensively studied using linear theory and nonlinear simulations in the past. Here using 3D hybrid simulations, we show that PDI is still effective in turbulent low-beta plasmas, generating slow modes and causing ion heating. Selected events in WIND data are analyzed to identify slow modes in the solar wind and the role of PDI, and compared with our simulation results. We also investigate the validity of linear Vlasov theory regarding PDI growth and slow mode damping in turbulent plasmas. Since PDI favors low plasma beta, we expect to see more evidence of PDI in the solar wind close to the Sun, especially from the upcoming NASA's Parker Solar Probe mission which will provide unprecedented wave and plasma data as close as 8.5 solar radii from the Sun.

Targeting Alpha5 Beta1 Integrin to Prevent Metastatic Breast Cancer Cell Invasion: PhScN Target Site Definition and Plasma Stability

DTIC Science & Technology

2015-11-01

increased PhScN potency as a result of preventing endoproteolytic degradation. Finally, the in vivo lung extravasation and colonization data, as well as...successful colonization are late stages in breast cancer progression that are ultimately fatal. Hence, prevention of extravasation which leads to colony...Award Number: TITLE: “Targeting Alpha5 Beta1 Integrin to Prevent Metastatic Breast Cancer Cell Invasion: PhScN Target Site Definition and Plasma

Effect of multiple dosing of ketoconazole on pharmacokinetics of midazolam, a cytochrome P-450 3A substrate in beagle dogs.

PubMed

Kuroha, Masanori; Azumano, Akinori; Kuze, Yoji; Shimoda, Minoru; Kokue, Eiichi

2002-01-01

To evaluate effects of multiple dosing of ketoconazole (KTZ) on hepatic CYP3A, the pharmacokinetics of intravenous midazolam (MDZ, 0.5 mg/kg) before and during multiple dosing of KTZ were investigated in beagle dogs. KTZ tablets were given orally to dogs (n = 4) for 30 days (200 mg b.i.d.). With coadministration of KTZ, t(1/2beta) of MDZ were significantly increased both on day 1 (2-fold) and on day 30 (3-fold). Total body clearance (CL(tot)) of MDZ declined gradually during the first 5 days after the start of KTZ treatment, and thereafter CL(tot) appeared to reach a plateau phase (one-fourth), depending on plasma KTZ concentrations. The effects of KTZ on the biotransformation of MDZ were also investigated using dog liver microsomes (n = 5). The K(i) values of KTZ for MDZ 1'-hydroxylation and 4-hydroxylation were 0.0237 and 0.111 microM, respectively, indicating that KTZ extensively inhibits hepatic CYP3A activity in dogs. CL(tot) values estimated from in vitro K(i) values corrected by unbound fraction of KTZ and unbound concentrations of the drug in plasma were consistent with in vivo CL(tot) of MDZ. The results in this study suggest that KTZ treatment is necessary until plasma concentrations of the drug reach a steady state to evaluate the effect of multiple dosing of the drug on hepatic CYP3A in vivo. In addition, it is suggested that K(i) values corrected by unbound fraction of KTZ and unbound concentrations of the drug in plasma enable precise in vitro-in vivo scaling.

Bakery products enriched with phytosterol esters, alpha-tocopherol and beta-carotene decrease plasma LDL-cholesterol and maintain plasma beta-carotene concentrations in normocholesterolemic men and women.

PubMed

Quílez, Joan; Rafecas, Magda; Brufau, Gemma; García-Lorda, Pilar; Megías, Isabel; Bulló, Mònica; Ruiz, Joan A; Salas-Salvadó, Jordi

2003-10-01

The hypocholesterolemic effects of phytosterols have not been evaluated in bakery products, and the addition of liposoluble antioxidants to the carrier has never been tested. We investigated the effects of consuming croissants and magdalenas (Spanish muffins) enriched with sterol esters, alpha-tocopherol and beta-carotene on plasma lipid and fat-soluble antioxidant concentrations in normocholesterolemic, habitual consumers of bakery products following their usual diet and lifestyle. Using a randomized, double-blind, placebo-controlled design, the control (C) group (n = 29) received two pieces daily (standard croissant and muffin) and the sterol ester (SE) group (n = 28), the same products with sterol esters added (3.2 g/d) for 8 wk. Total and LDL cholesterol (LDL-C) decreased in the SE group by 0.24 mmol/L (P < 0.01) and 0.26 mmol/L (P < 0.005), respectively, whereas these variables did not change in the control group. The total difference in total and LDL-C changes between groups was 0.38 mmol/L (8.9%) and 0.36 mmol/L (14.7%), respectively (P < 0.001). Within-group changes in HDL cholesterol, triacylglycerol or lipoprotein(a) concentrations did not differ. Similarly, within-group changes over time in plasma tocopherol and carotenoid concentrations did not differ between groups. Our findings suggest that bakery products are excellent carriers for phytosterols, and their consumption is associated with a decrease in total and LDL-C concentrations, with no changes in alpha-tocopherol and beta-carotene. The ability of bakery products to include sufficient quantities of beta-carotene to compensate for a potential deficiency, and the fact that their efficacy was not associated with the time of day at which they were consumed, are interesting findings.

Radial and local time structure of the Saturnian ring current, revealed by Cassini

NASA Astrophysics Data System (ADS)

Sergis, N.; Jackman, C. M.; Thomsen, M. F.; Krimigis, S. M.; Mitchell, D. G.; Hamilton, D. C.; Dougherty, M. K.; Krupp, N.; Wilson, R. J.

2017-02-01

We analyze particle and magnetic field data obtained between July 2004 and December 2013 in the equatorial magnetosphere of Saturn, by the Cassini spacecraft. The radial and local time distribution of the total (thermal and suprathermal) particle pressure and total plasma beta (ratio of particle to magnetic pressure) over radial distances from 5 to 16 Saturn radii (RS = 60,258 km) is presented. The average azimuthal current density Jϕ and its separate components (inertial, pressure gradient, and anisotropy) are computed as a function of radial distance and local time and presented as equatorial maps. We explore the relative contribution of different physical mechanisms that drive the ring current at Saturn. Results show that (a) the particle pressure is controlled by thermal plasma inside of 8 RS and by the hot ions beyond 12 RS, exhibiting strong local time asymmetry with higher pressures measured at the dusk and night sectors; (b) the plasma beta increases with radial distance and remains >1 beyond 8-10 RS for all local times; (c) the ring current is asymmetric in local time and forms a maximum region between 7 and 13 RS, with values up to 100-115 pA/m2; and (d) the ring current is inertial everywhere inside of 7 RS, exhibits a mixed nature between 7 and 11 RS and is pressure gradient driven beyond 11 RS, with the exception of the noon sector where the mixed nature persists. In the dawn sector, it appears strongly pressure gradient driven for a wider range of radial distance, consistent with fast return flow of hot, tenuous magnetospheric plasma following tail reconnection.

Plasma Levels of Aβ42 and Tau Identified Probable Alzheimer's Dementia: Findings in Two Cohorts.

PubMed

Lue, Lih-Fen; Sabbagh, Marwan N; Chiu, Ming-Jang; Jing, Naomi; Snyder, Noelle L; Schmitz, Christopher; Guerra, Andre; Belden, Christine M; Chen, Ta-Fu; Yang, Che-Chuan; Yang, Shieh-Yueh; Walker, Douglas G; Chen, Kewei; Reiman, Eric M

2017-01-01

The utility of plasma amyloid beta (Aβ) and tau levels for the clinical diagnosis of Alzheimer's disease (AD) dementia has been controversial. The main objective of this study was to compare Aβ42 and tau levels measured by the ultra-sensitive immunomagnetic reduction (IMR) assays in plasma samples collected at the Banner Sun Health Institute (BSHRI) (United States) with those from the National Taiwan University Hospital (NTUH) (Taiwan). Significant increase in tau levels were detected in AD subjects from both cohorts, while Aβ42 levels were increased only in the NTUH cohort. A regression model incorporating age showed that tau levels identified probable ADs with 81 and 96% accuracy in the BSHRI and NTUH cohorts, respectively, while computed products of Aβ42 and tau increased the accuracy to 84% in the BSHRI cohorts. Using 382.68 (pg/ml) 2 as the cut-off value, the product achieved 92% accuracy in identifying AD in the combined cohorts. Overall findings support that plasma Aβ42 and tau assayed by IMR technology can be used to assist in the clinical diagnosis of AD.

A test of the Hall-MHD model: Application to low-frequency upstream waves at Venus

NASA Technical Reports Server (NTRS)

Orlowski, D. S.; Russell, C. T.; Krauss-Varban, D.; Omidi, N.

1994-01-01

Early studies suggested that in the range of parameter space where the wave angular frequency is less than the proton gyrofrequency and the plasma beta, the ratio of the thermal to magnetic pressure, is less than 1 magnetohydrodynamics provides an adequate description of the propagating modes in a plasma. However, recently, Lacombe et al. (1992) have reported significant differences between basic wave characteristics of the specific propagation modes derived from linear Vlasov and Hall-magnetohydrodynamic (MHD) theories even when the waves are only weakly damped. In this paper we compare the magnetic polarization and normalization magnetic compression ratio of ultra low frequency (ULF) upstream waves at Venus with magnetic polarization and normalized magnetic compression ratio derived from both theories. We find that while the 'kinetic' approach gives magnetic polarization and normalized magnetic compression ratio consistent with the data in the analyzed range of beta (0.5 less than beta less than 5) for the fast magnetosonic mode, the same wave characteristics derived from the Hall-MHD model strongly depend on beta and are consistent with the data only at low beta for the fast mode and at high beta for the intermediate mode.

Influence of Thermal Anisotropy on Equilibrium Stellarator Beta Limits

NASA Astrophysics Data System (ADS)

Bechtel, T. A.; Hegna, C. C.; Sovinec, C. R.

2017-10-01

The effect of anisotropic heat conduction on the upper beta limit of stellarator plasmas is studied using the nonlinear, extended MHD code NIMROD. The configuration under investigation is an l=2, M=10 torsatron with vacuum rotational transform near unity. Finite-beta plasmas are created using a volumetric heating source and temperature dependent resistivity; modeled with 22 stellarator symmetric (integer multiples of M) toroidal modes. Extended MHD simulations are then performed to generate steady state solutions that represent 3D equilibria. With increased heating, Shafranov shifts occur, and the associated break up of edge magnetic surfaces limits the achievable beta. Due to the presence of finite parallel heat conduction, pressure profiles can exist in regions of magnetic stochasticity. Here, we present results of independently varying the parallel and perpendicular thermal anisotropy. In particular, simulations show that the attained stored energy is a function of the magnitude of parallel and perpendicular thermal conduction for a given heat source, indicating that equilibrium beta limits are sensitive to anisotropic transport properties. Preliminary studies of MHD stability with non-stellarator symmetric modes, near the highest achievable beta, are also presented. Research supported by US DOE under Grant No. DE-FG02-99ER54546.

Associations of beta-endorphin with HVA and MHPG in the plasma of prepubertal boys: effects of familial drug abuse and antisocial personality disorder liability.

PubMed

Moss, H B; Yao, J K

1996-06-01

It is well-established that the secretion of the opioid neuropeptide beta-endorphin is perturbed by the administration of various drugs of abuse. Several investigators have speculated that variations in beta-endorphin secretory regulation may precede the development of a substance use disorder, and thus be a component of the liability for substance abuse. In order to test this hypothesis, we examined fasting, morning plasma concentrations of beta-endorphin and two catecholamine metabolites in prepubertal boys naive to drugs of abuse and at elevated familial risk for a substance use disorder (SA+), and in controls (SA-). Specifically, the dopaminergic metabolite homovanillic acid (pHVA), and the noradrenergic metabolite, 3-methoxy-4-hydroxy-phenylglycol (pMHPG) were measured. Between-group differences were not found for beta-endorphin, pHVA, or pMHPG. Similarly, such differences did not differentiate sons of fathers with Antisocial Personality Disorder and controls. However, regression analysis revealed that although both pHVA and pMHPG predicted beta-endorphin concentrations to similar degrees, the directions of influence were the opposite. pHVA was found to be positively associated with beta-endorphin while pMHPG was found to be negatively associated with beta-endorphin. No between-group differences in these relationships were found. The results suggest an opponent process in catecholaminergic regulation of beta-endorphin in humans, and are consistent with observations in the central nervous system of animal models.

Extension of the operational regime of the LHD towards a deuterium experiment

NASA Astrophysics Data System (ADS)

Takeiri, Y.; Morisaki, T.; Osakabe, M.; Yokoyama, M.; Sakakibara, S.; Takahashi, H.; Nakamura, Y.; Oishi, T.; Motojima, G.; Murakami, S.; Ito, K.; Ejiri, A.; Imagawa, S.; Inagaki, S.; Isobe, M.; Kubo, S.; Masamune, S.; Mito, T.; Murakami, I.; Nagaoka, K.; Nagasaki, K.; Nishimura, K.; Sakamoto, M.; Sakamoto, R.; Shimozuma, T.; Shinohara, K.; Sugama, H.; Watanabe, K. Y.; Ahn, J. W.; Akata, N.; Akiyama, T.; Ashikawa, N.; Baldzuhn, J.; Bando, T.; Bernard, E.; Castejón, F.; Chikaraishi, H.; Emoto, M.; Evans, T.; Ezumi, N.; Fujii, K.; Funaba, H.; Goto, M.; Goto, T.; Gradic, D.; Gunsu, Y.; Hamaguchi, S.; Hasegawa, H.; Hayashi, Y.; Hidalgo, C.; Higashiguchi, T.; Hirooka, Y.; Hishinuma, Y.; Horiuchi, R.; Ichiguchi, K.; Ida, K.; Ido, T.; Igami, H.; Ikeda, K.; Ishiguro, S.; Ishizaki, R.; Ishizawa, A.; Ito, A.; Ito, Y.; Iwamoto, A.; Kamio, S.; Kamiya, K.; Kaneko, O.; Kanno, R.; Kasahara, H.; Kato, D.; Kato, T.; Kawahata, K.; Kawamura, G.; Kisaki, M.; Kitajima, S.; Ko, W. H.; Kobayashi, M.; Kobayashi, S.; Kobayashi, T.; Koga, K.; Kohyama, A.; Kumazawa, R.; Lee, J. H.; López-Bruna, D.; Makino, R.; Masuzaki, S.; Matsumoto, Y.; Matsuura, H.; Mitarai, O.; Miura, H.; Miyazawa, J.; Mizuguchi, N.; Moon, C.; Morita, S.; Moritaka, T.; Mukai, K.; Muroga, T.; Muto, S.; Mutoh, T.; Nagasaka, T.; Nagayama, Y.; Nakajima, N.; Nakamura, Y.; Nakanishi, H.; Nakano, H.; Nakata, M.; Narushima, Y.; Nishijima, D.; Nishimura, A.; Nishimura, S.; Nishitani, T.; Nishiura, M.; Nobuta, Y.; Noto, H.; Nunami, M.; Obana, T.; Ogawa, K.; Ohdachi, S.; Ohno, M.; Ohno, N.; Ohtani, H.; Okamoto, M.; Oya, Y.; Ozaki, T.; Peterson, B. J.; Preynas, M.; Sagara, S.; Saito, K.; Sakaue, H.; Sanpei, A.; Satake, S.; Sato, M.; Saze, T.; Schmitz, O.; Seki, R.; Seki, T.; Sharov, I.; Shimizu, A.; Shiratani, M.; Shoji, M.; Skinner, C.; Soga, R.; Stange, T.; Suzuki, C.; Suzuki, Y.; Takada, S.; Takahata, K.; Takayama, A.; Takayama, S.; Takemura, Y.; Takeuchi, Y.; Tamura, H.; Tamura, N.; Tanaka, H.; Tanaka, K.; Tanaka, M.; Tanaka, T.; Tanaka, Y.; Toda, S.; Todo, Y.; Toi, K.; Toida, M.; Tokitani, M.; Tokuzawa, T.; Tsuchiya, H.; Tsujimura, T.; Tsumori, K.; Usami, S.; Velasco, J. L.; Wang, H.; Watanabe, T.-H.; Watanabe, T.; Yagi, J.; Yajima, M.; Yamada, H.; Yamada, I.; Yamagishi, O.; Yamaguchi, N.; Yamamoto, Y.; Yanagi, N.; Yasuhara, R.; Yatsuka, E.; Yoshida, N.; Yoshinuma, M.; Yoshimura, S.; Yoshimura, Y.

2017-10-01

As the finalization of a hydrogen experiment towards the deuterium phase, the exploration of the best performance of hydrogen plasma was intensively performed in the large helical device. High ion and electron temperatures, T i and T e, of more than 6 keV were simultaneously achieved by superimposing high-power electron cyclotron resonance heating onneutral beam injection (NBI) heated plasma. Although flattening of the ion temperature profile in the core region was observed during the discharges, one could avoid degradation by increasing the electron density. Another key parameter to present plasma performance is an averaged beta value ≤ft< β \\right> . The high ≤ft< β \\right> regime around 4% was extended to an order of magnitude lower than the earlier collisional regime. Impurity behaviour in hydrogen discharges with NBI heating was also classified with a wide range of edge plasma parameters. The existence of a no impurity accumulation regime, where the high performance plasma is maintained with high power heating  >10 MW, was identified. Wide parameter scan experiments suggest that the toroidal rotation and the turbulence are the candidates for expelling impurities from the core region.

Survey of Coherent Approximately 1 Hz Waves in Mercury's Inner Magnetosphere from MESSENGER Observations

NASA Technical Reports Server (NTRS)

Boardsen, Scott A.; Slavin, James A.; Anderson, Brian J.; Korth, Haje; Schriver, David; Solomon, Sean C.

2012-01-01

We summarize observations by the MESSENGER spacecraft of highly coherent waves at frequencies between 0.4 and 5 Hz in Mercury's inner magnetosphere. This survey covers the time period from 24 March to 25 September 2011, or 2.1 Mercury years. These waves typically exhibit banded harmonic structure that drifts in frequency as the spacecraft traverses the magnetic equator. The waves are seen at all magnetic local times, but their observed rate of occurrence is much less on the dayside, at least in part the result of MESSENGER's orbit. On the nightside, on average, wave power is maximum near the equator and decreases with increasing magnetic latitude, consistent with an equatorial source. When the spacecraft traverses the plasma sheet during its equatorial crossings, wave power is a factor of 2 larger than for equatorial crossings that do not cross the plasma sheet. The waves are highly transverse at large magnetic latitudes but are more compressional near the equator. However, at the equator the transverse component of these waves increases relative to the compressional component as the degree of polarization decreases. Also, there is a substantial minority of events that are transverse at all magnetic latitudes, including the equator. A few of these latter events could be interpreted as ion cyclotron waves. In general, the waves tend to be strongly linear and characterized by values of the ellipticity less than 0.3 and wave-normal angles peaked near 90 deg. Their maxima in wave power at the equator coupled with their narrow-band character suggests that these waves might be generated locally in loss cone plasma characterized by high values of the ratio beta of plasma pressure to magnetic pressure. Presumably both electromagnetic ion cyclotron waves and electromagnetic ion Bernstein waves can be generated by ion loss cone distributions. If proton beta decreases with increasing magnetic latitude along a field line, then electromagnetic ion Bernstein waves are predicted to transition from compressional to transverse, a pattern consistent with our observations. We hypothesize that these local instabilities can lead to enhanced ion precipitation and directly feed field-line resonances.

Preclinical evaluation of an 18F-labelled beta1-adrenoceptor selective radioligand based on ICI 89,406.

PubMed

Law, Marilyn P; Wagner, Stefan; Kopka, Klaus; Renner, Christiane; Pike, Victor W; Schober, Otmar; Schäfers, Michael

2010-05-01

Radioligand binding studies indicate a down-regulation of myocardial beta(1)-adrenoceptors (beta(1)-AR) in cardiac disease which may or may not be associated with a decrease in beta(2)-ARs. We have chosen ICI 89,406, a beta(1)-selective AR antagonist, as the lead structure to develop new beta(1)-AR radioligands for PET and have synthesised a fluoro-ethoxy derivative (F-ICI). (S)-N-[2-[3-(2-Cyano-phenoxy)-2-hydroxy-propylamino]-ethyl]-N'-[4-(2-[(18)F]fluoro-ethoxy)-phenyl]-urea ((S)-[(18)F]F-ICI) was synthesised. Myocardial uptake of radioactivity after intravenous injection of (S)-[(18)F]F-ICI into adult CD(1) mice or Wistar rats was assessed with positron emission tomography (PET) and postmortem dissection. Metabolism was assessed by high-performance liquid chromatography analysis of plasma and urine. The heart was visualised with PET after injection of (S)-[(18)F]F-ICI but neither unlabelled F-ICI nor propranolol (non-selective beta-AR antagonist) injected 15 min after (S)-[(18)F]F-ICI affected myocardial radioactivity. Ex vivo dissection demonstrated that predosing with propranolol or CGP 20712 (beta(1)-selective AR-antagonist) did not affect myocardial radioactivity. Radiometabolites rapidly appeared in plasma and both (S)-[(18)F]F-ICI and radiometabolites accumulated in urine. Myocardial uptake of (S)-[(18)F]F-ICI after intravenous injection was mainly at sites unrelated to beta(1)-ARs. (S)-[(18)F]F-ICI is not a suitable beta(1)-selective-AR radioligand for PET. (c) 2010 Elsevier Inc. All rights reserved.

Integrated Plasma Control for Alternative Plasma Shape on EAST

NASA Astrophysics Data System (ADS)

Xiao, Bingjia

2017-10-01

To support long pulse plasma operation in high performance, a set of plasma control algorithms such as PEFIT real-time equilibrium reconstruction, radiation feedback, Beta and loop voltage feedback and quasi-snowflake shape f control have been implemented on EAST Plasma Control system (PCS) which was adapted from DIII-D PCS. PEFIT is a parallelized version of EFIT by using GPU with highest computation acceleration ratio up to 100 with respect to EFIT. It demonstrated high performance both in DIII-D data analysis and in the real-time shape control on EAST plasma either in normal or quasi-snowflake shape. Loop voltage has been successfully controlled by Low Hybrid Wave (LHW) while the plasma current is maintained by poloidal field coil set. Beta control has been also demonstrated by using LHW and it will be extended to other heating sources because the PCS interface is ready. Radiation feedback control has been achieved by Neon seeding by Super-Sonic Molecular Beam Injection (SMBI). For the plasma operation in quasi-snowflake, we have reached 20 s ELMy free high confinement non-inductive discharges with betap 2, H98 1.1 and plasma current 250 kA. EAST orals.

Spontaneous healing and growth of locked magnetic island chains in toroidal plasmas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fitzpatrick, R.; Waelbroeck, F. L.

2012-11-15

Recent experiments have demonstrated that locked magnetic island chains in stellarator plasmas spontaneously heal under certain conditions, and spontaneously grow under others. A formalism initially developed to study magnetic island dynamics in tokamak plasmas is employed to investigate this phenomenon. It is found that island healing/growth transitions can be caused either by a breakdown in torque balance in the vicinity of the island chain, or by an imbalance between the various terms in the island width evolution equation. The scaling of the healing/growth thresholds with the standard dimensionless plasma parameters {beta}, {nu}{sub *}, and {rho}{sub *} is determined. In accordancemore » with the experimental data, it is found that island healing generally occurs at high {beta} and low {nu}{sub *}, and island growth at low {beta} and high {nu}{sub *}. In further agreement, it is found that island healing is accompanied an ion poloidal velocity shift in the electron diamagnetic direction, and island growth by a velocity shift in the ion diamagnetic direction. Finally, it is found that there is considerable hysteresis in the healing/growth cycle, as is also seen experimentally.« less

Improving enrichment of circulating fetal DNA for genetic testing: size fractionation followed by whole gene amplification.

PubMed

Jorgez, Carolina J; Bischoff, Farideh Z

2009-01-01

Among the pitfalls of using cell-free fetal DNA in plasma for prenatal diagnosis is quality of the recovered DNA fragments and concomitant presence of maternal DNA (>95%). Our objective is to provide alternative methods for achieving enrichment and high-quality fetal DNA from plasma. Cell-free DNA from 31 pregnant women and 18 controls (10 males and 8 females) were size separated using agarose gel electrophoresis. DNA fragments of 100-300, 500-700 and 1,500-2,000 bp were excised and extracted, followed by whole genome amplification (WGA) of recovered fragments. Levels of beta-globin and DYS1 were measured. Distribution of beta-globin size fragments was similar among pregnant women and controls. Among control male cases, distribution of size fragments was the same for both beta-globin and DYS1. Among maternal cases confirmed to be male, the smallest size fragment (100-300 bp) accounted for nearly 50% (39.76 +/- 17.55%) of the recovered DYS1-DNA (fetal) and only 10% (10.40 +/- 6.49%) of beta-globin (total) DNA. After WGA of plasma fragments from pregnant women, DYS1 sequence amplification was best observed when using the 100-300 bp fragments as template. Combination of electrophoresis for size separation and WGA led to enriched fetal DNA from plasma. This novel combination of strategies is more likely to permit universal clinical applications of cell-free fetal DNA. Copyright 2009 S. Karger AG, Basel.

A quantitative real-time RT-PCR assay to measure TGF-beta mRNA and its correlation with hematologic, plasma chemistry and organo-somatic indices responses in triamcinolone-treated Atlantic menhaden, Brevoortia tyrannus.

PubMed

Johnson, A K; Harms, C A; Levine, J F; Law, J McHugh

2006-01-01

A quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) assay was developed to measure transforming growth factor-beta (TGF-beta) in Atlantic menhaden (Brevoortia tyrannus), an estuarine-dependent species plagued by ulcerative skin lesions in the estuaries along the eastern United States. Atlantic menhaden were acclimated in a closed system for two weeks prior to initiation of the study. The synthetic glucocorticoid, triamcinolone acetonide (10mg/kg body weight) was administered by intracoelomic injection and its effect on the splenic mononuclear cell TGF-beta mRNA transcription, liver-somatic index, spleno-somatic index, hematology, and plasma chemistry were compared to untreated fish at 48 and 96h post-treatment. Triamcinolone-treated Atlantic menhaden showed suppression of TGF-beta mRNA production, neutrophilia, monocytosis, lymphopenia, and an increase in blood glucose concentrations. The health indices used in this study may help us interpret some of the changes observed during the development of ulcerative skin lesions in wild-caught menhaden.

Association between Plasma Levels of Transforming Growth Factor-beta1, IL-23 and IL-17 and the Severity of Autism in Egyptian Children

ERIC Educational Resources Information Center

Hashim, Haitham; Abdelrahman, Hadeel; Mohammed, Doaa; Karam, Rehab

2013-01-01

It has been recently shown that dysregulation of transforming growth factor-beta1 (TGF-beta1), IL-23 and IL-17 has been identified as a major factor involved in autoimmune disorders. Based on the increasing evidence of immune dysfunction in autism the aim of this study was to measure serum levels of TGF-beta1, IL-23 and IL-17 in relation to the…

Modulation of vitellogenin synthesis through estrogen receptor beta-1 in goldfish (Carassius auratus) juveniles exposed to 17-{beta} estradiol and nonylphenol

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soverchia, L.; Ruggeri, B.; Palermo, F.

2005-12-15

Many synthetic chemicals, termed xenoestrogens, have been shown to interact as agonists with the estrogen receptor (ER) to elicit biological responses similar to those of natural hormones. To date, the regulation of vitellogenesis in oviparous vertebrates has been widely used for evaluation of estrogenic effects. Therefore, Carassius auratus juveniles were chosen as a fish model for studying the effects of estradiol-17{beta} and different concentrations (10{sup -6} and 10{sup -7} M) of 4-nonylphenol (4-NP) on the expression of liver ER{beta}-1 subtype; plasma vitellogenin and sex steroids (androgens and estradiol-17{beta}) were also evaluated together with the bioaccumulation process, through mass-spectrometry. C. auratusmore » is a species widespread in the aquatic environment and, on the toxicological point of view, can be considered a good 'sentinel' species. Juveniles of goldfish were maintained in tanks with only tap water or water with different concentrations (10{sup -6} and 10{sup -7} M) of 4-nonylphenol (4-NP), or 10{sup -7} M of estradiol-17{beta}. After 3 weeks of treatment, animals were anesthetized within 5 min after capture, and blood was immediately collected into heparinized syringes by cardiac puncture and stored at -70 deg. C; the gonads were fixed, then frozen and stored at -70 deg. C; the whole fish, liver, and muscle tissues were harvested and immediately stored at -70 deg. C for molecular biology experiments and bioaccumulation measurements. The estrogenic effects of 4-NP were evidenced by the presence of plasma vitellogenin in juveniles exposed both to estradiol-17{beta} and the two doses of 4-NP; moreover, exposure to 4-NP also increased aromatization of androgens, as suggested by decreasing androgens and increasing estradiol-17{beta} plasma levels. The changes of these parameters were in agreement with the increasing transcriptional rate of ER{beta}-1 mRNA in the liver, demonstrating that both estradiol-17{beta} and 4-NP modulate the vitellogenin rate through interaction with the ER{beta}-1 subtype. The present study also suggests that 4-NP at the concentration of 10{sup -6} M bioaccumulates in the liver.« less

Ion-Scale Spectral Break in the Normal Plasma Beta Range in the Solar Wind Turbulence

NASA Astrophysics Data System (ADS)

Wang, X.; Tu, C.-Y.; He, J.-S.; Wang, L.-H.

2018-01-01

The spectral break (fb) of magnetic fluctuations at the ion scale in the solar wind is considered to give important clue on the turbulence dissipation mechanism. Among several possible mechanisms, the most notable two are related respectively to proton thermal gyroradius ρi and proton inertial length di. The corresponding frequencies of them are fρi=VSW/(2πρi) and fdi=VSW/(2πdi), respectively, where VSW is the solar wind speed. However, no definite conclusion has been given for which one is more reasonable because the two parameters have similar value when plasma beta β ˜ 1. Here we do a statistical study to see if the two ratios fb/fρi and fb/fdi have different dependence on β in the solar wind turbulence with 0.1 < β < 1.3. From magnetic measurements by the Wind spacecraft, we select 141 data sets with each one longer than 13 h. We find that the ratio fb/fdi is statistically not dependent on β, and the average value of it is 0.48 ± 0.06. However, fb/fρi increases with increasing β clearly and is significantly smaller than fb/fdi when β < 0.8. These new results show that fb is statistically 0.48fdi, and the influence of β could be negligible in the studied β range. It indicates a preference of the dissipation mechanism associated with di in the solar wind with 0.1 < β < 0.8. Further theoretical studies are needed to give detailed explanation.

Spectrophotometric and cytochemical analyses of phosphatase activity in Beta vulgaris L.

PubMed

Pesacreta, T C; Bennett, A B; Lucas, W J

1986-03-01

Spectrophotometric and cytochemical methods were used to investigate the localization and/or the sensitivity of phosphatase activities in aldehyde-fixed beet leaves and membrane fractions. The nonspecific acid phosphatase substrates, p-nitrophenyl phosphate and beta-glycerol phosphate, each exhibited unique spectrophotometric patterns of hydrolysis as a function of pH. Additionally, beta-glycerol phosphatase activity was primarily present on the tonoplast, whereas p-nitrophenyl phosphatase was present on the plasma membrane. Because of the unique pH response of each enzyme and their different localization, we conclude that they cannot be entirely "nonspecific." The spectrophotometric pattern of ATP hydrolysis differed from that of p-nitrophenol phosphate in that it decreased at pH 5.0-5.5 and was greatly inhibited by 10 mM sodium fluoride; however, both activities were on the plasma membrane. Therefore, we conclude that these activities represent either two enzymes or only one enzyme that differs in its ability to hydrolyze these two substrates. Generally, enzymatically produced lead deposits on the plasma membrane of non-vascular cells were as frequent and large as those on phloem cells; frequently, deposits on sieve element plasma membranes were relatively small. We therefore conclude that there is no evidence for the presence of relatively intense ATPase activity on the plasma membrane of phloem cells in beet leaf, in contrast to other species. Studies with membrane fractions indicated that formaldehyde could completely inhibit the inhibitor-sensitive phosphatase activities in mitochondrial and vacuolar fractions while preserving significant activity in the plasma membrane fraction.

Permutation methods for the structured exploratory data analysis (SEDA) of familial trait values.

PubMed

Karlin, S; Williams, P T

1984-07-01

A collection of functions that contrast familial trait values between and across generations is proposed for studying transmission effects and other collateral influences in nuclear families. Two classes of structured exploratory data analysis (SEDA) statistics are derived from ratios of these functions. SEDA-functionals are the empirical cumulative distributions of the ratio of the two contrasts computed within each family. SEDA-indices are formed by first averaging the numerator and denominator contrasts separately over the population and then forming their ratio. The significance of SEDA results are determined by a spectrum of permutation techniques that selectively shuffle the trait values across families. The process systematically alters certain family structure relationships while keeping other familial relationships intact. The methodology is applied to five data examples of plasma total cholesterol concentrations, reported height values, dermatoglyphic pattern intensity index scores, measurements of dopamine-beta-hydroxylase activity, and psychometric cognitive test results.

Application of very high harmonic fast waves for off-axis current drive in the DIII-D and FNSF-AT tokamaks

DOE PAGES

Prater, Ronald; Moeller, Charles P.; Pinsker, Robert I.; ...

2014-06-26

Fast waves at frequencies far above the ion cyclotron frequency and approaching the lower hybrid frequency (also called “helicons” or “whistlers”) have application to off-axis current drive in tokamaks with high electron beta. The high frequency causes the whistler-like behavior of the wave power nearly following field lines, but with a small radial component, so the waves spiral slowly toward the plasma center. The high frequency also contributes to strong damping. Modeling predicts robust off-axis current drive with good efficiency compared to alternatives in high performance discharges in DIII-D and Fusion Nuclear Science Facility (FNSF) when the electron beta ismore » above about 1.8%. Detailed analysis of ray behavior shows that ray trajectories and damping are deterministic (that is, not strongly affected by plasma profiles or initial ray conditions), unlike the chaotic ray behavior in lower frequency fast wave experiments. Current drive was found to not be sensitive to the launched value of the parallel index of refraction n||, so wave accessibility issues can be reduced. Finally, use of a traveling wave antenna provides a very narrow n|| spectrum, which also helps avoid accessibility problems.« less

Analysis of adrenocortical secretory responses during acute an prolonged immune stimulation in inflammation-susceptible and -resistant rat strains.

PubMed

Andersson, I M; Lorentzen, J C; Ericsson-Dahlstrand, A

2000-11-01

Endogenous corticosterone secreted during immune challenge restricts the inflammatory process and genetic variations in this neuroendocrine-immune dialogue have been suggested to influence an individuals sensitivity to develop chronic inflammatory disorders. We have tested inflammation-susceptible Dark Agouti (DA) rats and resistant, MHC-identical, PVG.1AV1 rats for their abilities to secrete corticosterone in response to acute challenge with bacterial lipopolysaccharide (LPS) or a prolonged activation of the nonspecific immune system with arthritogenic yeast beta-glucan. Intravenous injection of LPS triggered equipotent secretion of corticosterone in both rat strains. Interestingly, peak concentrations of corticosterone did not differ significantly between the strains. Intradermal injection of beta-glucan caused severe, monophasic, polyarthritis in DA rats while PVG.1AV1 responded with significantly milder joint inflammation. Importantly, serial sampling of plasma from glucan-injected DA and PVG.1AV1 rats did not reveal elevated concentrations of plasma corticosterone at any time from days 1-30 postinjection compared to preinjection values, in spite of the ongoing inflammatory process. Interestingly, adrenalectomized, beta-glucan-challenged DA rats responded with an aggravated arthritic process, indicating an anti-inflammatory role for the basal levels of corticosterone that were detected in intact DA rats challenged with beta-glucan. Moreover, substitution with subcutaneous corticosterone-secreting pellets, yielding moderate stress-levels, significantly attenuated the arthritic response. In contrast, adrenalectomized and glucan-challenged PVG.1AV1 rats did not respond with an elevated arthritic response, suggesting that these rats contain the arthritic process via corticosterone-independent mechanisms. In conclusion, the hypothalamic-pituitary-adrenal axis in both rat strains exhibited strong activation after challenge with LPS. This contrasted to the basal corticosterone levels observed strains during a prolonged arthritic process. No correlation between ability to secrete corticosterone and susceptibility to inflammation could be demonstrated. Basal levels of endogenous corticosterone appeared to restrain inflammation in beta-glucan-challenged DA rats whereas resistance to inflammation in PVG.1AV1 rats may be mediated via corticosterone-independent mechanisms.

Joint DIII-D/EAST research on the development of a high poloidal beta scenario for the steady state missions of ITER and CFETR

NASA Astrophysics Data System (ADS)

Garofalo, A. M.; Gong, X. Z.; Ding, S. Y.; Huang, J.; McClenaghan, J.; Pan, C. K.; Qian, J.; Ren, Q. L.; Staebler, G. M.; Chen, J.; Cui, L.; Grierson, B. A.; Hanson, J. M.; Holcomb, C. T.; Jian, X.; Li, G.; Li, M.; Pankin, A. Y.; Peysson, Y.; Zhai, X.; Bonoli, P.; Brower, D.; Ding, W. X.; Ferron, J. R.; Guo, W.; Lao, L. L.; Li, K.; Liu, H.; Lyv, B.; Xu, G.; Zang, Q.

2018-01-01

Experimental and modeling investigations on the DIII-D and EAST tokamaks show the attractive transport and stability properties of fully noninductive, high poloidal-beta (β P ) plasmas, and their suitability for steady-state operating scenarios in ITER and CFETR. A key feature of the high-β P regime is the large-radius (ρ > 0.6) internal transport barrier (ITB), often observed in all channels (ne, Te, Ti, rotation), and responsible for both excellent energy confinement quality and excellent stability properties. Experiments on DIII-D have shown that, with a large-radius ITB, very high β N and β P values (both ≥ 4) can be reached by taking advantage of the stabilizing effect of a nearby conducting wall. Synergistically, higher plasma pressure provides turbulence suppression by Shafranov shift, leading to ITB sustainment independent of the plasma rotation. Experiments on EAST have been used to assess the long pulse potential of the high-β P regime. Using RF-only heating and current drive, EAST achieved minute-long fully noninductive steady state H-mode operation with strike points on an ITER-like tungsten divertor. Improved confinement (relative to standard H-mode) and steady state ITB features are observed with a monotonic q-profile with q min ˜ 1.5. Separately, experiments have shown that increasing the density in plasmas driven by lower hybrid wave broadens the q-profile, a technique that could enable a large radius ITB. These experimental results have been used to validate MHD, current drive, and turbulent transport models, and to project the high-β P regime to a burning plasma. These projections suggest the Shafranov shift alone will not suffice to provide improved confinement (over standard H-mode) without rotation and rotation shear. However, increasing the negative magnetic shear (higher q on axis) provides a similar turbulence suppression mechanism to Shafranov shift, and can help devices such as ITER and CFETR achieve their steady-state fusion goals.

Effects of acupuncture and transcutaneous stimulation analgesia on plasma hormone levels during and after major abdominal surgery.

PubMed

Kho, H G; Kloppenborg, P W; van Egmond, J

1993-05-01

The effects of acupuncture and transcutaneous electrical stimulation (TES) on plasma adrenaline (A) and noradrenaline (NA), adrenocorticotropic hormone (ACTH), beta-endorphin (beta E), anti-diuretic hormone (ADH) and hydrocortisone (cortisol) were evaluated during and, for four days after surgery in 42 male patients submitted to a standardized major abdominal operation in a comparative study of three different anaesthetic techniques. Group 1 received acupuncture and transcutaneous stimulation as the main non-pharmacological analgesic during surgery. Group 2 received moderate-dose fentanyl (initial bolus of 10 micrograms kg-1 followed by continuous infusion of 5 micrograms kg-1 h-1 for the first hour, and then 4 micrograms kg-1 h-1. Group 3 received a combination of both methods. In all three groups analgesia was supplemented, if necessary, by small bolus injections of 50 micrograms fentanyl. Anaesthesia was induced in all groups with thiopentone 5 mg kg-1 and vecuronium 0.1 mg kg-1 and patients were ventilated (N2O:O2 = 2:1) to achieve normocapnia without the use of a halogenated agent. Pre-operatively acupuncture plus TES in Groups 1 and 3 led to a rise in beta E (P < 0.05) without changes of haemodynamics. After intubation beta E did not increase further. Intubation in Group 2 led to an increase of beta E (P < 0.05) also, and to a rise in pulse rate and blood pressure (P < 0.05) in all three groups. Per-operatively acupuncture plus TES in Group 1 showed a response of circulating NA and cortisol similar to that in Groups 2 and 3, whereas the responses of the circulating A, ACTH, beta E and ADH in Group 1 were more pronounced (P < 0.01). Post-operatively no differences in the hormonal profiles could be discerned between the groups with or without acupuncture plus TES (Group 2 vs. Group 3) nor between those with or without moderate-dose fentanyl anaesthesia (Group 1 vs. Group 3). It is concluded that acupuncture and TES have no effect on the cardiovascular response to laryngoscopy and intubation. They can replace moderate-dose fentanyl anaesthesia in major abdominal surgery at the cost of a more enhanced per-operative neuroendocrine stress response, which does not, however, influence the postoperative hormonal profiles nor the rapidity of return to pre-operative values.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lazarus, E; Peng, Yueng Kay Martin

Oak Ridge National Laboratory (ORNL) proposes to build the Spherical Torus Experiment (STX), a very low aspect ratio toroidal confinement device. This proposal concentrates on tokamak operation of the experiment; however, it can in principle be operated as a pinch or reversed-field pinch as well. As a tokamak, the spherical torus confines a plasma that is characterized by high toroidal beta, low poloidal beta, large natural elongation, high plasma current for a given edge q, and strong paramagnetism. These features combine to offer the possibility of a compact, low-field fusion device. The figure below shows that when compared to amore » conventional tokamak the spherical torus represents a major change in geometry. The primary goals of the experiment will be to demonstrate a capability for high beta (20%) in the first stability regime, to extend our knowledge of tokamak confinement scaling, and to test oscillating-field current drive. The experiment will operate in the high-beta, collisionless regime, which is achieved in STX at low temperatures because of the geometry. At a minimum, operation of STX will help to resolve fundamental questions regarding the scaling of beta and confinement in tokamaks. Complete success in this program would have a significant impact on toroidal fusion research in that it would demonstrate solutions to the problems of beta and steady-state operation in the tokamak. The proposed device has a major radius of 0.45 m, a toroidai field of 0.5 T, a plasma current of 900 kA, and heating by neutral beam injection. We estimate 30 months for design, construction, and assembly. The budget estimate, including contingency and escalation, is $6.8 million.« less

Pregnancy outcome in dairy and beef cattle after artificial insemination and treatment with seminal plasma or transforming growth factor beta-1.

PubMed

Odhiambo, J F; Poole, D H; Hughes, L; Dejarnette, J M; Inskeep, E K; Dailey, R A

2009-09-01

Reduced capability of the uterus to support pregnancy in the absence of its interaction with secretions from male accessory glands has been demonstrated in rodents and to some extent in pigs. However, in cattle, the role of postmating inflammatory response on pregnancy success has not been studied. The current study examined the influence of uterine presensitization with seminal antigens at breeding on pregnancy outcome in cows. Lactating beef (n=1090) and dairy (n=800) cows received 0.5 mL seminal plasma (SP), 40 ng recombinant human transforming growth factor-beta1 (rhTGF-beta1), or 0.5 mL bovine serum albumin (BSA), or were left untreated before or at insemination. Semen was deposited into the anterior cervix using a second insemination gun. Pregnancy was diagnosed at 35 to 40 d postinsemination by transrectal ultrasonography or from records of calves born the subsequent calving season. Pregnancy rates in beef cows did not differ among treatments but differed among trials (69.8%, 52.5% vs. 40.3%; P<0.05). In trials where average pregnancy rates were below 50%, treatments with TGF-beta1 but not SP tended (P<0.07) to increase pregnancy rates in beef cows. In dairy cows, SP and TGF-beta1 improved pregnancy outcome by 10 percentage points, but these increments did not achieve statistical significance. In conclusion, this study did not find any conclusive evidence for the effect of TGF-beta1 or seminal plasma on pregnancy outcome in lactating dairy or beef cows but realized marginal improvements when pregnancy rates were below 50% (compromised fertility).

Consumption of both resistant starch and beta-glucan improves postprandial plasma glucose and insulin in women.

PubMed

Behall, Kay M; Scholfield, Daniel J; Hallfrisch, Judith G; Liljeberg-Elmståhl, Helena G M

2006-05-01

Consumption of a meal high in resistant starch or soluble fiber (beta-glucan) decreases peak insulin and glucose concentrations and areas under the curve (AUCs). The objective was to determine whether the effects of soluble fiber and resistant starch on glycemic variables are additive. Ten normal-weight (43.5 years of age, BMI 22.0 kg/m2) and 10 overweight women (43.3 years of age, BMI 30.4 kg/m2) consumed 10 tolerance meals in a Latin square design. Meals (1 g carbohydrate/kg body wt) were glucose alone or muffins made with different levels of soluble fiber (0.26, 0.68, or 2.3 g beta-glucan/100 g muffin) and three levels of resistant starch (0.71, 2.57, or 5.06 g/100 g muffin). Overweight subjects had plasma insulin concentrations higher than those of normal-weight subjects but maintained similar plasma glucose levels. Compared with low beta-glucan-low resistant starch muffins, glucose and insulin AUC decreased when beta-glucan (17 and 33%, respectively) or resistant starch (24 and 38%, respectively) content was increased. The greatest AUC reduction occurred after meals containing both high beta-glucan-high resistant starch (33 and 59% lower AUC for glucose and insulin, respectively). Overweight women were somewhat more insulin resistant than control women. Soluble fiber appears to have a greater effect on postprandial insulin response while glucose reduction is greater after resistant starch from high-amylose cornstarch. The reduction in glycemic response was enhanced by combining resistant starch and soluble fiber. Consumption of foods containing moderate amounts of these fibers may improve glucose metabolism in both normal and overweight women.

Determination of N,N-dimethyltryptamine and beta-carboline alkaloids in human plasma following oral administration of Ayahuasca.

PubMed

Yritia, Mercedes; Riba, Jordi; Ortuño, Jordi; Ramirez, Ariel; Castillo, Araceli; Alfaro, Yolanda; de la Torre, Rafael; Barbanoj, Manel J

2002-11-05

Ayahuasca is a South American psychotropic beverage prepared from plants native to the Amazon River Basin. It combines the hallucinogenic agent and 5-HT(2A/2C) agonist N,N-dimethyltryptamine (DMT) with beta-carboline alkaloids showing monoamine oxidase-inhibiting properties. In the present paper, an analytical methodology for the plasma quantification of the four main alkaloids present in ayahuasca plus two major metabolites is described. DMT was extracted by liquid-liquid extraction with n-pentane and quantified by gas chromatography with nitrogen-phosphorus detection. Recovery was 74%, and precision and accuracy were better than 9.9%. The limit of quantification (LOQ) was 1.6 ng/ml. Harmine, harmaline, and tetrahydroharmine (THH), the three main beta-carbolines present in ayahuasca, and harmol and harmalol (O-demethylation metabolites of harmine and harmaline, respectively) were measured in plasma by means of high-performance liquid chromatography (HPLC) with fluorescence detection. Sample preparation was accomplished by solid-phase extraction, which facilitated the automation of the process. All five beta-carbolines were measured using a single detector by switching wavelengths. Separation of harmol and harmalol required only slight changes in the chromatographic conditions. Method validation demonstrated good recoveries, above 87%, and accuracy and precision better than 13.4%. The LOQ was 0.5 ng/ml for harmine, 0.3 ng/ml for harmaline, 1.0 ng/ml for THH, and 0.3 ng/ml for harmol and harmalol. Good linearity was observed in the concentration ranges evaluated for DMT (2.5-50 ng/ml) and the beta-carbolines (0.3-100 ng/ml). The gas chromatography and HPLC methods described allowed adequate characterization of the pharmacokinetics of the four main alkaloids present in ayahuasca, and also of two major beta-carboline metabolites not previously described in the literature.

Design and experimental results of the 1-T Bitter Electromagnet Testing Apparatus (BETA)

NASA Astrophysics Data System (ADS)

Bates, E. M.; Birmingham, W. J.; Romero-Talamás, C. A.

2018-05-01

The Bitter Electromagnet Testing Apparatus (BETA) is a 1-Tesla (T) technical prototype of the 10 T Adjustable Long Pulsed High-Field Apparatus. BETA's final design specifications are highlighted in this paper which include electromagnetic, thermal, and stress analyses. We discuss here the design and fabrication of BETA's core, vessel, cooling, and electrical subsystems. The electrical system of BETA is composed of a scalable solid-state DC breaker circuit. Experimental results display the stable operation of BETA at 1 T. These results are compared to both analytical design and finite element calculations. Experimental results validate analytical magnet designing methods developed at the Dusty Plasma Laboratory. The theoretical steady state maxima and the limits of BETA's design are explored in this paper.

Design and experimental results of the 1-T Bitter Electromagnet Testing Apparatus (BETA).

PubMed

Bates, E M; Birmingham, W J; Romero-Talamás, C A

2018-05-01

The Bitter Electromagnet Testing Apparatus (BETA) is a 1-Tesla (T) technical prototype of the 10 T Adjustable Long Pulsed High-Field Apparatus. BETA's final design specifications are highlighted in this paper which include electromagnetic, thermal, and stress analyses. We discuss here the design and fabrication of BETA's core, vessel, cooling, and electrical subsystems. The electrical system of BETA is composed of a scalable solid-state DC breaker circuit. Experimental results display the stable operation of BETA at 1 T. These results are compared to both analytical design and finite element calculations. Experimental results validate analytical magnet designing methods developed at the Dusty Plasma Laboratory. The theoretical steady state maxima and the limits of BETA's design are explored in this paper.

THE SPATIO-TEMPORAL EVOLUTION OF SOLAR FLARES OBSERVED WITH AIA/SDO: FRACTAL DIFFUSION, SUB-DIFFUSION, OR LOGISTIC GROWTH?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aschwanden, Markus J., E-mail: aschwanden@lmsal.com

2012-09-20

We explore the spatio-temporal evolution of solar flares by fitting a radial expansion model r(t) that consists of an exponentially growing acceleration phase, followed by a deceleration phase that is parameterized by the generalized diffusion function r(t){proportional_to}{kappa}(t - t{sub 1}){sup {beta}/2}, which includes the logistic growth limit ({beta} = 0), sub-diffusion ({beta} = 0-1), classical diffusion ({beta} = 1), super-diffusion ({beta} = 1-2), and the linear expansion limit ({beta} = 2). We analyze all M- and X-class flares observed with Geostationary Operational Environmental Satellite and Atmospheric Imaging Assembly/Solar Dynamics Observatory (SDO) during the first two years of the SDO mission,more » amounting to 155 events. We find that most flares operate in the sub-diffusive regime ({beta} = 0.53 {+-} 0.27), which we interpret in terms of anisotropic chain reactions of intermittent magnetic reconnection episodes in a low plasma-{beta} corona. We find a mean propagation speed of v = 15 {+-} 12 km s{sup -1}, with maximum speeds of v{sub max} = 80 {+-} 85 km s{sup -1} per flare, which is substantially slower than the sonic speeds expected for thermal diffusion of flare plasmas. The diffusive characteristics established here (for the first time for solar flares) is consistent with the fractal-diffusive self-organized criticality model, which predicted diffusive transport merely based on cellular automaton simulations.« less

Exercise and Beta-Glucan Consumption (Saccharomyces cerevisiae) Improve the Metabolic Profile and Reduce the Atherogenic Index in Type 2 Diabetic Rats (HFD/STZ)

PubMed Central

Andrade, Eric Francelino; Lima, Andressa Ribeiro Veiga; Nunes, Ingrid Edwiges; Orlando, Débora Ribeiro; Gondim, Paula Novato; Zangeronimo, Márcio Gilberto; Alves, Fernando Henrique Ferrari; Pereira, Luciano José

2016-01-01

Physical activity and the ingestion of dietary fiber are non-drug alternatives commonly used as adjuvants to glycemic control in diabetic individuals. Among these fibers, we can highlight beta-glucans. However, few studies have compared isolated and synergic effects of physical exercise and beta-glucan ingestion, especially in type 2 diabetic rats. Therefore, we evaluated the effects beta-glucan (Saccharomyces cerevisiae) consumption, associated or not to exercise, on metabolic parameters of diabetic Wistar rats. The diabetes mellitus (DM) was induced by high-fat diet (HFD) associated with a low dose of streptozotocin (STZ—35 mg/kg). Trained groups were submitted to eight weeks of exercise in aquatic environment. In the last 28 days of experiment, animals received 30 mg/kg/day of beta-glucan by gavage. Isolated use of beta-glucan decreased glucose levels in fasting, Glycated hemoglobin (HbA1c), triglycerides (TAG), total cholesterol (TC), low-density lipoprotein (LDL-C), the atherogenic index of plasma. Exercise alone also decreased blood glucose levels, HbA1c, and renal lesions. An additive effect for reducing the atherogenic index of plasma and renal lesions was observed when both treatments were combined. It was concluded that both beta-glucan and exercise improved metabolic parameters in type 2 (HFD/STZ) diabetic rats. PMID:27999319

Effects of chemical sympathectomy on the increases in plasma catecholamines and dopamine-beta-hydroxylase induced by forced immobilization and insulin-induced hypoglycemia: origin and fate of plasma dopamine-beta-hydroxylase.

PubMed

Israel, A S; Barbella, Y R; Cubeddu, L X

1982-06-01

The effect of acute stresses on plasma norepinephrine, epinephrine and dopamine-beta-hydroxylase (DBH) were evaluated in control and 6-hydroxydopamine-treated, awake cannulated guinea pigs. Forced immobolization for 1 hr caused a 3- and 5-fold increase in plasma DBH and norepinephrine, respectively. Pretreatment with 6-hydroxydopamine (23 mg/kg b.wt.i.a., 72 and 48 hr before stress) reduced by 70% the increase in plasma DBH and totally prevented the rise in plasma catecholamines evoked by the restraining stress. Injection of insulin (5 U/kg b.wt.i.a.) induced a 60% decrease in blood glucose, a 1-fold increase in plasma DBH and a selective 4-fold increase in plasma epinephrine; these effects were not modified by chemical sympathectomy. Our results indicate that forced immobilization and hypoglycemia produce a preferential activation of the sympathetic postganglionic nerves and of the adrenal medulla, respectively, and that in guinea pigs both stresses increase plasma DBH. The kinetics of disappearance of plasma DBH were studied after subjecting the guinea pigs for 1 hr to forced immobilization. Although 7 of 12 animals showed a biphasic rate of fall of plasma DBH, in each case there was a rapid initial fall possibly due to the "distribution" of the enzyme with a T1/2 of 1.65 hr. Similar findings were observed in 6-hydroxydopamine-treated guinea pigs. These results suggest that the distribution of DBH is the most important process in reducing the augmented plasma DBH levels elicited by a short-term stress and that this process is not dependent on the integrity of the sympathetic nerves nor on the adrenal or sympathetic origin of the enzyme. This study supports the view that the ratio, content of releasable DBH present in sympathetic nerves and adrenal glands/total circulating pool of DBH, is the factor that determines whether an increase in plasma DBH would occur in animals exposed to an acute stress.

Nutrient intake and hormonal status of premenopausal vegetarian Seventh-day Adventists and premenopausal nonvegetarians.

PubMed

Shultz, T D; Leklem, J E

1983-01-01

The relationship between dietary nutrients and plasma estrone, estradiol-17 beta, estriol, dehydroepiandrosterone sulfate, and prolactin levels was investigated in 14 premenopausal Seventh-day Adventist vegetarian (SV) women and 9 premenopausal non-Seventh-day Adventist nonvegetarian (NV) women. The SV subjects consumed less fat, especially saturated fat, and used significantly less fried food than the NV subjects. Plasma levels of estrone and estradiol-17 beta in the SV subjects were significantly lower than in the NV subjects. SV estradiol-17 beta and estriol levels were positively correlated with linoleic acid and protein intake, while NV prolactin levels were significantly correlated with intakes of oleic and linoleic acids and total fat. The data suggest that specific dietary nutrients were related to the hormonal milieu of these SV and NV subjects.

Diverse effects of a low dose supplement of lipidated curcumin in healthy middle aged people

PubMed Central

2012-01-01

Background Curcumin extracts of turmeric are proposed to produce health benefits. To date, human intervention studies have focused mainly on people with existing health problems given high doses of poorly absorbed curcumin. The purpose of the current study was to check whether in healthy people, a low dose of a lipidated curcumin extract could alter wellness-related measures. Methods The present study was conducted in healthy middle aged people (40–60 years old) with a low dose of curcumin (80 mg/day) in a lipidated form expected to have good absorption. Subjects were given either curcumin (N = 19) or placebo (N = 19) for 4 wk. Blood and saliva samples were taken before and after the 4 weeks and analyzed for a variety of blood and saliva measures relevant to health promotion. Results Curcumin, but not placebo, produced the following statistically significant changes: lowering of plasma triglyceride values, lowering of salivary amylase levels, raising of salivary radical scavenging capacities, raising of plasma catalase activities, lowering of plasma beta amyloid protein concentrations, lowering of plasma sICAM readings, increased plasma myeloperoxidase without increased c-reactive protein levels, increased plasma nitric oxide, and decreased plasma alanine amino transferase activities. Conclusion Collectively, these results demonstrate that a low dose of a curcumin-lipid preparation can produce a variety of potentially health promoting effects in healthy middle aged people. PMID:23013352

Natural products with hypoglycemic, hypotensive, hypocholesterolemic, antiatherosclerotic and antithrombotic activities.

PubMed

Wang, H X; Ng, T B

1999-01-01

This article reviews compounds of botanical origin which are capable of lowering plasma levels of glucose and cholesterol and blood pressure, as well as compounds inhibiting atherosclerosis and thrombosis. Hypoglycemic natural products comprise flavonoids, xanthones, triterpenoids, alkaloids, glycosides, alkyldisulfides, aminobutyric acid derivatives, guanidine, polysaccharides and peptides. Hypotensive compounds include flavonoids, diterpenes, alkaloids, glycosides, polysaccharides and proteins. Among natural products with hypocholesterolemic activity are beta-carotene, lycopene, cycloartenol, beta-sitosterol, sitostanol, saponin, soybean protein, indoles, dietary fiber, propionate, mevinolin (beta-hydroxy-beta-methylglutaryl coenzyme A reductase inhibitor) and polysaccharides. Heparins, flavonoids, tocotrienols, beta-hydroxy-beta-methylglutaryl coenzyme A reductase inhibitors (statins), garlic compounds and fungal proteases exert antithrombotic action. Statins and garlic compounds also possess antiatherosclerotic activity.

Abrupt withdrawal of beta-blocking agents in patients with arterial hypertension. Effect on blood pressure, heart rate and plasma catecholamines and prolactin.

PubMed

Lederballe Pedersen, O; Mikkelsen, E; Lanng Nielsen, J; Christensen, N J

1979-04-17

Chronic treatment with beta-blockers was interrupted abruptly in six patients with arterial hypertension. Three patients, who had experienced symptoms during a previous withdrawal, again complained of transient palpitations, tremor, sweating, headache and general malaise. A significant increase in standing blood pressure (BP) and heart rate (HR) was noted after 24 h. The standing HR reached a maximum after 48 h and had decreased significantly on the 7th day (p less than 0.005). There was a strong tendency to greater increase in standing BP and HR in the patients who experienced symptoms than in those who did not. Plasma concentrations of noradrenaline, adrenaline and prolactin did not change significantly. Thus, beta-blocker withdrawal symptoms are reproducible and are indicative of a transient sympathetic hyperresponse. The increased activity is not likely to be caused by increased production of circulating catecholamines, but rather by increased sensitivity of the beta-receptor.

Comparison of the effects of agalsidase alfa and agalsidase beta on cultured human Fabry fibroblasts and Fabry mice.

PubMed

Sakuraba, Hitoshi; Murata-Ohsawa, Mai; Kawashima, Ikuo; Tajima, Youichi; Kotani, Masaharu; Ohshima, Toshio; Chiba, Yasunori; Takashiba, Minako; Jigami, Yoshifumi; Fukushige, Tomoko; Kanzaki, Tamotsu; Itoh, Kohji

2006-01-01

We compared two recombinant alpha-galactosidases developed for enzyme replacement therapy for Fabry disease, agalsidase alfa and agalsidase beta, as to specific alpha-galactosidase activity, stability in plasma, mannose 6-phosphate (M6P) residue content, and effects on cultured human Fabry fibroblasts and Fabry mice. The specific enzyme activities of agalsidase alfa and agalsidase beta were 1.70 and 3.24 mmol h(-1) mg protein(-1), respectively, and there was no difference in stability in plasma between them. The M6P content of agalsidase beta (3.6 mol/mol protein) was higher than that of agalsidase alfa (1.3 mol/mol protein). The administration of both enzymes resulted in marked increases in alpha-galactosidase activity in cultured human Fabry fibroblasts, and Fabry mouse kidneys, heart, spleen and liver. However, the increase in enzyme activity in cultured fibroblasts, kidneys, heart and spleen was higher when agalsidase beta was used. An immunocytochemical analysis revealed that the incorporated recombinant enzyme degraded the globotriaosyl ceramide accumulated in cultured Fabry fibroblasts in a dose-dependent manner, with the effect being maintained for at least 7 days. Repeated administration of agalsidase beta apparently decreased the number of accumulated lamellar inclusion bodies in renal tubular cells of Fabry mice.

Imaging of laboratory magnetospheric plasmas using coherence imaging technique

NASA Astrophysics Data System (ADS)

Nishiura, Masaki; Takahashi, Noriki; Yoshida, Zensho; Nakamura, Kaori; Kawazura, Yohei; Kenmochi, Naoki; Nakatsuka, Masataka; Sugata, Tetsuya; Katsura, Shotaro; Howard, John

2017-10-01

The ring trap 1 (RT-1) device creates a laboratory magnetosphere for the studies on plasma physics and advanced nuclear fusion. A levitated superconducting coil produces magnetic dipole fields that realize a high beta plasma confinement that is motivated by self-organized plasmas in planetary magnetospheres. The electron cyclotron resonance heating (ECRH) with 8.2 GHz and 50 kW produces the plasmas with hot electrons in a few ten keV range. The electrons contribute to the local electron beta that exceeded 1 in RT-1. For the ion heating, ion cyclotron range of frequencies (ICRF) heating with 2-4 MHz and 10 kW has been performed in RT-1. The radial profile of ion temperature by a spectroscopic measurement indicates the signature of ion heating. In the holistic point of view, a coherence imaging system has been implemented for imaging the entire ion dynamics in the laboratory magnetosphere. The diagnostic system and obtained results will be presented.

Pain reactivity and plasma beta-endorphin in children and adolescents with autistic disorder.

PubMed

Tordjman, Sylvie; Anderson, George M; Botbol, Michel; Brailly-Tabard, Sylvie; Perez-Diaz, Fernando; Graignic, Rozenn; Carlier, Michèle; Schmit, Gérard; Rolland, Anne-Catherine; Bonnot, Olivier; Trabado, Séverine; Roubertoux, Pierre; Bronsard, Guillaume

2009-08-26

Reports of reduced pain sensitivity in autism have prompted opioid theories of autism and have practical care ramifications. Our objective was to examine behavioral and physiological pain responses, plasma beta-endorphin levels and their relationship in a large group of individuals with autism. The study was conducted on 73 children and adolescents with autism and 115 normal individuals matched for age, sex and pubertal stage. Behavioral pain reactivity of individuals with autism was assessed in three observational situations (parents at home, two caregivers at day-care, a nurse and child psychiatrist during blood drawing), and compared to controls during venepuncture. Plasma beta-endorphin concentrations were measured by radioimmunoassay. A high proportion of individuals with autism displayed absent or reduced behavioral pain reactivity at home (68.6%), at day-care (34.2%) and during venepuncture (55.6%). Despite their high rate of absent behavioral pain reactivity during venepuncture (41.3 vs. 8.7% of controls, P<0.0001), individuals with autism displayed a significantly increased heart rate in response to venepuncture (P<0.05). Moreover, this response (Delta heart rate) was significantly greater than for controls (mean+/-SEM; 6.4+/-2.5 vs. 1.3+/-0.8 beats/min, P<0.05). Plasma beta-endorphin levels were higher in the autistic group (P<0.001) and were positively associated with autism severity (P<0.001) and heart rate before or after venepuncture (P<0.05), but not with behavioral pain reactivity. The greater heart rate response to venepuncture and the elevated plasma beta-endorphin found in individuals with autism reflect enhanced physiological and biological stress responses that are dissociated from observable emotional and behavioral reactions. The results suggest strongly that prior reports of reduced pain sensitivity in autism are related to a different mode of pain expression rather than to an insensitivity or endogenous analgesia, and do not support opioid theories of autism. Clinical care practice and hypotheses regarding underlying mechanisms need to assume that children with autism are sensitive to pain.

Rebound weight gain as associated with high plasma norepinephrine levels that are mediated through polymorphisms in the beta2-adrenoceptor.

PubMed

Masuo, Kazuko; Katsuya, Tomohiro; Kawaguchi, Hideki; Fu, Yuxiao; Rakugi, Hiromi; Ogihara, Toshio; Tuck, Michael L

2005-11-01

A successful weight loss program is essential treatment for obesity-related diseases, but it is well known that the majority of individuals do not succeed in weight loss maintenance. The present study evaluates hormonal mechanisms and the relationship of beta2-adrenoceptor polymorphisms involved in individuals who regain weight after initially successful weight loss. Overweight Japanese men (n = 154) were enrolled in a 24-month weight loss program. Body mass index (BMI), total body fat mass, plasma norepinephrine (NE) and leptin levels, and beta2-adrenoceptor polymorphisms (Arg16Gly, Gln27Glu) were measured every 6 months for the 24-month period. Maintenance of weight loss was defined as significant weight loss (>or=10% reduction) from entry weight at 6 months and maintenance of the weight loss for an additional 18 months. Rebound weight gain was defined as significant weight loss at 6 months but subsequent regain of body weight during the next 18 months. The results showed that 37 subjects maintained weight loss during 24 months, whereas 36 subjects had rebound weight gain. The BMI at entry and calorie intake and physical activity at each period were similar between the two groups. Subjects who maintained weight loss had at entry a significantly lower fat mass and plasma NE levels compared to those with rebound weight gain. Body fat mass, NE, and leptin levels at entry predicted the degree of change in body weight during the 24-month study period. Subjects with rebound weight gain had a significantly higher frequency of the Gly16 allele for the beta2-adrenoceptor polymorphism compared to subjects who had a 24-month maintenance of weight loss. Subjects carrying the Gly16 allele also had significantly higher plasma NE, leptin, and body fat mass levels and a greater waist-to-hip ratio both at entry and throughout the study. A high initial degree of body fat mass and high plasma NE levels as determined by the Gly16 allele for the beta2-adrenoceptor polymorphisms predict those individuals who will have rebound weight gain after their initial successful weight loss.

Modulational instability of finite-amplitude, circularly polarized Alfven waves

NASA Technical Reports Server (NTRS)

Derby, N. F., Jr.

1978-01-01

The simple theory of the decay instability of Alfven waves is strictly applicable only to a small-amplitude parent wave in a low-beta plasma, but, if the parent wave is circularly polarized, it is possible to analyze the situation without either of these restrictions. Results show that a large-amplitude circularly polarized wave is unstable with respect to decay into three waves, one longitudinal and one transverse wave propagating parallel to the parent wave and one transverse wave propagating antiparallel. The transverse decay products appear at frequencies which are the sum and difference of the frequencies of the parent wave and the longitudinal wave. The decay products are not familiar MHD modes except in the limit of small beta and small amplitude of the parent wave, in which case the decay products are a forward-propagating sound wave and a backward-propagating circularly polarized wave. In this limit the other transverse wave disappears. The effect of finite beta is to reduce the linear growth rate of the instability from the value suggested by the simple theory. Possible applications of these results to the theory of the solar wind are briefly touched upon.

Effect of radiation on metabolism of selected minerals in cattle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sasser, L.B.; Wade, L. Jr.; Bell, M.C.

1974-01-01

Zinc, Cu, Ca, Mg, and Fe contents of plasma and/or erythrocytes of steers were studied following exposure of the steers to either whole-body gamma irradiation, BETA irradiation of the gastrointestinal tract, BETA irradiation of the skin, or all combinations of the above. Gastrointestinal (GI) irradiation reduced plasma Zn concentrations 1, 2, and 3 weeks after irradiation, but no detectable change occurred in the erythrocyte concentration of stable Zn. The uptake of /sup 65/Zn by erythrocytes from control steers averaged about 5%; whereas the uptakes of the GI- and skin-irradiated steers exceeded l0%. Hypoferremia and hypercupremia accompanied the injury and infectionmore » produced by GI and skin irradiation. The decline of plasma Ca and Mg levels following GI irradiation appeared to be the result of radiation-induced anorexia, as control animals with a restricted feed intake had a similar reduction in plasma Ca and Mg. (auth)« less

Control of neoclassical tearing modes by sawtooth control.

PubMed

Sauter, O; Westerhof, E; Mayoral, M L; Alper, B; Belo, P A; Buttery, R J; Gondhalekar, A; Hellsten, T; Hender, T C; Howell, D F; Johnson, T; Lamalle, P; Mantsinen, M J; Milani, F; Nave, M F F; Nguyen, F; Pecquet, A L; Pinches, S D; Podda, S; Rapp, J

2002-03-11

The onset of a neoclassical tearing mode (NTM) depends on the existence of a large enough seed island. It is shown in the Joint European Torus that NTMs can be readily destabilized by long-period sawteeth, such as obtained by sawtooth stabilization from ion-cyclotron heating or current drive. This has important implications for burning plasma scenarios, as alpha particles strongly stabilize the sawteeth. It is also shown that, by adding heating and current drive just outside the inversion radius, sawteeth are destabilized, resulting in shorter sawtooth periods and larger beta values being obtained without NTMs.

Purified reconstituted lac carrier protein from Escherichia coli is fully functional.

PubMed

Viitanen, P; Garcia, M L; Kaback, H R

1984-03-01

Proteoliposomes reconstituted with lac carrier protein purified from the plasma membrane of Escherichia coli catalyze each of the translocation reactions typical of the beta-galactoside transport system (i.e., active transport, counterflow, facilitated influx and efflux) with turnover numbers and apparent Km values comparable to those observed in right-side-out membrane vesicles. Furthermore, detailed kinetic studies show that the reconstituted system exhibits properties analogous to those observed in membrane vesicles. Imposition of a membrane potential (delta psi, interior negative) causes a marked decrease in apparent Km (by a factor of 7 to 10) with a smaller increase in Vmax (approximately equal to 3-fold). At submaximal values of delta psi, the reconstituted carrier exhibits biphasic kinetics, with one component manifesting the kinetic parameters of active transport and the other exhibiting the characteristics of facilitated diffusion. Finally, at low lactose concentrations, the initial velocity of influx varies linearly with the square of the proton electro-chemical gradient. The results provide quantitative support for the contention that a single polypeptide species, the product of the lac y gene, is responsible for each of the transport reactions typical of the beta-galactoside transport system.

Strength and fracture mechanism of iron reinforced tricalcium phosphate cermet fabricated by spark plasma sintering.

PubMed

Tkachenko, Serhii; Horynová, Miroslava; Casas-Luna, Mariano; Diaz-de-la-Torre, Sebastian; Dvořák, Karel; Celko, Ladislav; Kaiser, Jozef; Montufar, Edgar B

2018-05-01

The present work studies the microstructure and mechanical performance of tricalcium phosphate (TCP) based cermet toughened by iron particles. A novelty arises by the employment of spark plasma sintering for fabrication of the cermet. Results showed partial transformation of initial alpha TCP matrix to beta phase and the absence of oxidation of iron particles, as well as a lack of chemical reaction between TCP and iron components during sintering. The values of compressive and tensile strength of TCP/Fe cermet were 3.2 and 2.5 times, respectively, greater than those of monolithic TCP. Fracture analysis revealed the simultaneous action of crack-bridging and crack-deflection microstructural toughening mechanisms under compression. In contrast, under tension the reinforcing mechanism was only crack-bridging, being the reason for smaller increment of strength. Elastic properties of the cermet better matched values reported for human cortical bone. Thereby the new TCP/Fe cermet has potential for eventual use as a material for bone fractures fixation under load-bearing conditions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Influence of the IL-1Ra gene polymorphism on in vivo synthesis of IL-1Ra and IL-1beta after live yellow fever vaccination.

PubMed

Hacker, U T; Erhardt, S; Tschöp, K; Jelinek, T; Endres, S

2001-09-01

The inflammatory response in infectious and autoimmune diseases is regulated by the balance between pro- and anti-inflammatory cytokines. The IL-1 complex contains polymorphic genes coding for IL-1alpha, IL-1beta and IL-1Ra. The IL-1Ra (variable number of tanden repeat) VNTR polymorphism has been shown to influence the capacity to produce IL-1beta and IL-1Ra after in vitro stimulation. Allele 2 of this polymorphism is associated with a number of inflammatory diseases. To determine the impact of the IL-1Ra polymorphism on in vivo human cytokine synthesis, we used a yellow fever vaccination model for the induction of cytokine synthesis in healthy volunteers. Two different yellow fever vaccines were used. After administration of the RKI vaccine (34 volunteers), plasma TNF-alpha concentration increased from 13.4 +/- 0.9 pg/ml to 23.3 +/- 1.1 pg/ml (P < 0.001), and plasma IL-1Ra concentration increased from 308 +/- 25 pg/ml to 1019 +/- 111 pg/ml (P < 0.001), on day 2. Using Stamaril vaccine, no increase in the plasma concentrations of either TNF-alpha or IL-1Ra could be detected (n = 17). Only the RKI vaccine induced TNF-alpha synthesis after in vitro stimulation of MNC. Carriers of allele 2 of the IL-1Ra polymorphism had increased baseline concentrations of IL-1Ra (350 +/- 32 pg/ml) compared with non-carriers (222 +/- 18 pg/ml, P < 0.001), and decreased concentrations of IL-1beta (0.9 +/- 0.2 pg/ml for carriers versus 2.8 +/- 0.7 pg/ml for non-carriers, P = 0.017). After yellow fever vaccination (RKI vaccine), no significant differences in the increase of IL-1Ra plasma levels were detected between carriers and non-carriers of allele 2 of the IL-1Ra gene polymorphism. This is the first study to examine the influence of this genetic polymorphism on in vivo-induced human IL-1beta and IL-1Ra synthesis. Baseline concentrations of IL-1Ra and IL-1beta were significantly influenced by the IL-1Ra polymorphism. No influence of the IL-1Ra polymorphism on the in vivo-induced production of IL-1Ra and IL-1beta could be detected.

Effect of acute stress on plasma beta-corticosterone, estradiol-17 beta and testosterone concentrations in juvenile American alligators collected from three sites within the Kissimmee-Everglades drainage basin in Florida (USA).

PubMed

Gunderson, M P; Kools, S A E; Milnes, M R; Guillette, L J

2003-07-01

The effect of acute stress on plasma beta-corticosterone (B), testosterone (T) and estradiol-17beta (E2) concentrations in juvenile alligators collected from sites with varying sediment contaminants was examined in this study. Dramatic increases in plasma B concentrations were observed in alligators from all of the sites after 2 h of capture although females from the intermediate contaminant site exhibited a significantly lower percentage increase in B than females from the other two sites. Males from the site with the highest contaminant levels exhibited elevated initial B concentrations relative to the other sites. This pattern was not observed after 2 h of restraint. Females from the highest contaminant site exhibited depressed initial T when compared to the other sites although this pattern was not observed after 2 h of restraint. Neither E2 nor T decreased after 2 h in females, whereas T concentrations decreased in all males over the same time period. The variance associated with these endpoints was also examined to determine whether it could serve as a more sensitive marker for perturbations of the endocrine system and stress response. Females from the higher and intermediate contaminant sites exhibited the lowest and highest standard errors (respectively) associated with 2 h plasma B concentrations with no differences among mean concentrations suggesting a perturbation of the stress response in these animals that was not detected by examining the means. We concluded that the environmental contaminants could be acting as stressors, leading to the observed differences.

Heterogeneity of Arabinogalactan-Proteins on the Plasma Membrane of Rose Cells.

PubMed Central

Serpe, M. D.; Nothnagel, E. A.

1996-01-01

Arabinogalactan-proteins (AGPs) have been purified from the plasma membrane of suspension-cultured Paul's Scarlet rose (Rosa sp.) cells. The two most abundant and homogeneous plasma membrane AGP fractions were named plasma membrane AGP1 (PM-AGP1) and plasma membrane AGP2 (PM-AGP2) and had apparent molecular masses of 140 and 217 kD, respectively. Both PM-AGP1 and PM-AGP2 had [beta]-(1-3)-, [beta]-(1,6)-, and [beta]-(1,3,6)-galactopyranosyl residues, predominantly terminal [alpha]-arabinofuranosyl residues, and (1,4)- and terminal glucuronopyranosyl residues. The protein moieties of PM-AGP1 and PM-AGP2 were both rich in hydroxyproline, alanine, and serine, but differed in the abundance of hydroxyproline, which was 1.6 times higher in PM-AGP2 than in PM-AGP1. Another difference was the overall protein content, which was 3.7% (w/w) in PM-AGP1 and 15% in PM-AGP2. As judged by their behavior on reverse-phase chromatography, PM-AGP1 and PM-AGP2 were not more hydrophobic than AGPs from the cell wall or culture medium. In contrast, a minor plasma membrane AGP fraction eluted later on reverse-phase chromatography and was more negatively charged at pH 5 than either PM-AGP1 or PM-AGP2. The more negatively charged fraction contained molecules with a glycosyl composition characteristic of AGPs and included at least two different macromolecules. The results of this investigation indicate that Rosa plasma membrane contains at least four distinct AGPs or AGP-like molecules. These molecules differed from each other in size, charge, hydrophobicity, amino-acyl composition, and/or protein content. PMID:12226444

Hall effect and fine structures in magnetic reconnection with high plasma {beta}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin, S.P.; Yang, H.A.; Wang, X.G.

2005-04-15

Magnetic reconnection with various plasma {beta} (the ratio of plasma pressure to the magnetic pressure) is studied numerically using a 2.5 dimensional Hall magnetohydrodynamics (MHD) code developed from a multistep implicit scheme. The initial state of the Hall MHD simulation is an equilibrium Harris sheet with L{sub c}=0.5d{sub i} (where L{sub c} is the half-width of the equilibrium current layer and d{sub i} is the ion inertial length) and a zero guide field (i.e., B{sub y0}=0 at t=0). Driven by a constant boundary inflow a quasisteady fast reconnection occurs in the plasma with a low uniform resistivity. The out-of-plane magneticmore » field component B{sub y} is then spontaneously generated and its quadrupolar structure is shown around the X point. It is demonstrated by the comparing studies that the reconnection dynamics is controlled by the Hall effect and the effect of scalar electron pressure gradient is negligible in the generalized Ohm's law. It is also found that the openness of the magnetic separatrix angle and associated quadrupolar B{sub y} structure is enlarged as {beta} increases. When {beta}>2.0 fine structures of B{sub y} contours with reversed sign emerge. The numerical results indicate that the variations in electron velocity V{sub e} are greater than those in ion velocity V{sub i} and the decoupling of electron and ion occurs in larger scale lengths than d{sub i} as {beta} increases. Clearly, the reserve current, which is associated with the relative motion between electrons and ions, generates the fine structures of B{sub y} contours in the outflow region. Then the corresponding profile of B{sub y} component exhibits a static whistler wave signature. Enhanced wave activities observed during a Cluster crossing of the high-{beta} exterior cusp region [Y. Khotyaintsev, A. Vaivads, Y. Ogawa, B. Popielawska, M. Andre, S. Buchert, P. Decreau, B. Lavraud, and H. Reme, Ann. Geophys. 22, 2403 (2004)] might be related to the Hall effects of magnetic reconnection shown in the present simulation.« less

Are [O-methyl-11C]derivatives of ICI 89,406 beta1-adrenoceptor selective radioligands suitable for PET?

PubMed

Law, Marilyn P; Wagner, Stefan; Kopka, Klaus; Pike, Victor W; Schober, Otmar; Schäfers, Michael

2008-01-01

Radioligand binding studies show that beta(1)-adrenoceptor (beta(1)-AR) density may be reduced in heart disease without down regulation of beta(2)-ARs. Radioligands are available for measuring total beta-AR density non-invasively with clinical positron emission tomography (PET) but none are selective for beta(1)- or beta(2)-ARs. The aim was to evaluate ICI 89,406, a beta(1)-AR-selective antagonist amenable to labelling with positron emitters, for PET. The S-enantiomer of an [O-methyl-(11)C] derivative of ICI 89,406 ((S)-[(11)C]ICI-OMe) was synthesised. Tissue radioactivity after i.v. injection of (S)-[(11)C]ICI-OMe (< 2 nmol x kg(-1)) into adult Wistar rats was assessed by small animal PET and post mortem dissection. Metabolism was assessed by HPLC of extracts prepared from plasma and tissues and by measuring [(11)C]CO(2) in exhaled air. The heart was visualised by PET after injection of (S)-[(11)C]ICI-OMe but neither unlabelled (S)-ICI-OMe nor propranolol (non-selective beta-AR antagonist) injected 15 min after (S)-[(11)C]ICI-OMe affected myocardial radioactivity. Ex vivo dissection showed that injecting unlabelled (S)-ICI-OMe, propranolol or CGP 20712A (beta(1)-selective AR antagonist) at high dose (> 2 mumol x kg(-1)) before (S)-[(11)C]ICI-OMe had a small effect on myocardial radioactivity. HPLC demonstrated that radioactivity in myocardium was due to unmetabolised (S)-[(11)C]ICI-OMe although (11)C-labelled metabolites rapidly appeared in plasma and liver and [(11)C]CO(2) was detected in exhaled air. Myocardial uptake of (S)-[(11)C]ICI-OMe after i.v. injection was low, possibly due to rapid metabolism in other tissues. Injection of unlabelled ligand or beta-AR antagonists had little effect indicating that binding was mainly to non-specific myocardial sites, thus precluding the use of (S)-[(11)C]ICI-OMe to assess beta(1)-ARs with PET.

Investigation of MHD instabilities and control in KSTAR preparing for high beta operation

NASA Astrophysics Data System (ADS)

Park, Y. S.; Sabbagh, S. A.; Bialek, J. M.; Berkery, J. W.; Lee, S. G.; Ko, W. H.; Bak, J. G.; Jeon, Y. M.; Park, J. K.; Kim, J.; Hahn, S. H.; Ahn, J.-W.; Yoon, S. W.; Lee, K. D.; Choi, M. J.; Yun, G. S.; Park, H. K.; You, K.-I.; Bae, Y. S.; Oh, Y. K.; Kim, W.-C.; Kwak, J. G.

2013-08-01

Initial H-mode operation of the Korea Superconducting Tokamak Advanced Research (KSTAR) is expanded to higher normalized beta and lower plasma internal inductance moving towards design target operation. As a key supporting device for ITER, an important goal for KSTAR is to produce physics understanding of MHD instabilities at long pulse with steady-state profiles, at high normalized beta, and over a wide range of plasma rotation profiles. An advance from initial plasma operation is a significant increase in plasma stored energy and normalized beta, with Wtot = 340 kJ, βN = 1.9, which is 75% of the level required to reach the computed ideal n = 1 no-wall stability limit. The internal inductance was lowered to 0.9 at sustained H-mode duration up to 5 s. In ohmically heated plasmas, the plasma current reached 1 MA with prolonged pulse length up to 12 s. Rotating MHD modes are observed in the device with perturbations having tearing rather than ideal parity. Modes with m/n = 3/2 are triggered during the H-mode phase but are relatively weak and do not substantially reduce Wtot. In contrast, 2/1 modes to date only appear when the plasma rotation profiles are lowered after H-L back-transition. Subsequent 2/1 mode locking creates a repetitive collapse of βN by more than 50%. Onset behaviour suggests the 3/2 mode is close to being neoclassically unstable. A correlation between the 2/1 mode amplitude and local rotation shear from an x-ray imaging crystal spectrometer suggests that the rotation shear at the mode rational surface is stabilizing. As a method to access the ITER-relevant low plasma rotation regime, plasma rotation alteration by n = 1, 2 applied fields and associated neoclassical toroidal viscosity (NTV) induced torque is presently investigated. The net rotation profile change measured by a charge exchange recombination diagnostic with proper compensation of plasma boundary movement shows initial evidence of non-resonant rotation damping by the n = 1, 2 applied field configurations. The result addresses perspective on access to low rotation regimes for MHD instability studies applicable to ITER. Computation of active RWM control using the VALEN-3D code examines control performance using midplane locked mode detection sensors. The LM sensors are found to be strongly affected by mode and control coil-induced vessel current, and consequently lead to limited control performance theoretically.

A soluble and active form of Wnt-3a protein is involved in myogenic differentiation after cholesterol depletion.

PubMed

Portilho, Débora M; Martins, Eliane R; Costa, Manoel L; Mermelstein, Cláudia S

2007-12-22

Cholesterol is one of the major lipids of plasma membranes. Recently, we have shown that cholesterol depletion by methyl-beta-cyclodextrin (M beta CD) induces the activation of the Wnt/beta-catenin pathway and enhances myogenic differentiation. Here, we show that M beta CD-conditioned media accelerates myogenesis in a similar way as M beta CD does, suggesting that the effects induced by M beta CD could be caused by soluble factors present in the culture medium. Soluble Wnt-3 protein is significantly enhanced in M beta CD-conditioned medium. Wnt-3a-enriched media induces myogenesis as much as M beta CD does, whereas Wnt-5a-enriched media inhibits. We suggest that Wnt-3a is involved in the myogenic induction observed after cholesterol depletion.

Final Report: Levitated Dipole Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kesner, Jay; Mauel, Michael

2013-03-10

Since the very first experiments with the LDX, research progress was rapid and significant. Initial experiments were conducted with the high-field superconducting coil suspended by three thin rods. These experiments produced long-pulse, quasi-steady-state microwave discharges, lasting more than 10 s, having peak beta values of 20% [Garnier, Phys. Plasmas, v13, p. 056111, 2006]. High-beta, near steady-state discharges have been maintained in LDX for more than 20 seconds, and this capability makes LDX the longest pulse fusion confinement experiment now operating in the U.S. fusion program. In both supported and levitated configurations, detailed measurements are made of discharge evolution, plasma dynamicsmore » and instability, and the roles of gas fueling, microwave power deposition profiles, and plasma boundary shape. High-temperature plasma is created by multifrequency electron cyclotron resonance heating allowing control of heating profiles. Depending upon neutral fueling rates, the LDX discharges contain a fraction of energetic electrons, with mean energies above 50 keV. Depending on whether or not the superconducting dipole is levitated or supported, the peak thermal electron temperature is estimated to exceed 500 eV and peak densities reach 1.0E18 (1/m3). Several significant discoveries resulted from the routine investigation of plasma confinement with a magnetically-levitated dipole. For the first time, toroidal plasma with pressure approaching the pressure of the confining magnetic field was well-confined in steady-state without a toroidal magnetic field. Magnetic levitation proved to be reliable and is now routine. The dipole's cryostat allows up to three hours of "float time" between re-cooling with liquid helium and providing scientists unprecedented access to the physics of magnetizd plasma. Levitation eliminates field-aligned particle sources and sinks and results in a toroidal, magnetically-confined plasma where profiles are determined by cross-field transport. We find levitation causes the central plasma density to increase dramatically and to significantly improve the confinement of thermal plasma [Boxer, Nature-Physics, v8, p. 949, 2010]. Several diagnostic systems have been used to measure plasma fluctuations, and these appear to represent low-frequency convection that may lead to adiabatic heating and strongly peaked pressure profiles. These experiments are remarkable, and the motivate wide-ranging studies of plasma found in space and confined for fusion energy. In the following report, we describe: (i) observations of the centrally-peaked density profile that appears naturally as a consequence of a strong turbulent pinch, (ii) observations of overall density and pressure increases that suggest large improvements to the thermal electron confinement time result occur during levitation, and (iii) the remarkable properties of low-frequency plasma fluctuations that cause magnetized plasma to "self-organize" into well-confined, centrally-peaked profiles that are relative to fusion and to space.« less

Integrated Scenario Modeling of NSTX Advanced Plasma Configurations

NASA Astrophysics Data System (ADS)

Kessel, Charles; Synakowski, Edward

2003-10-01

The Spherical Torus will provide an attractive fusion energy source if it can demonstrate the following major features: high elongation and triangularity, 100% non-inductive current with a credible path to high bootstrap fractions, non-solenoidal startup and current rampup, high beta with stabilization of RWM instabilities, and sufficiently high energy confinement. NSTX has specific experimental milestones to examine these features, and integrated scenario modeling is helping to understand how these configurations might be produced and what tools are needed to access this operating space. Simulations with the Tokamak Simulation Code (TSC), CURRAY, and JSOLVER/BALMSC/PEST2 have identified fully non-inductively sustained, high beta plasmas that rely on strong plasma shaping accomplished with a PF coil modification, off-axis current drive from Electron Bernstein Waves (EBW), flexible on-axis heating and CD from High Harmonic Fast Wave (HHFW) and Neutral Beam Injection (NBI), and density control. Ideal MHD stability shows that with wall stabilization through plasma rotation and/or RWM feedback coils, a beta of 40% is achievable, with 100% non-inductive current sustained for 4 current diffusion times. Experimental data and theory are combined to produce a best extrapolation to these regimes, which is continuously improved as the discharges approach these parameters, and theoretical/computational methods expand. Further investigations and development for integrated scenario modeling on NSTX is discussed.

Enhanced bioavailability of process-induced fast-dissolving ibuprofen cogranulated with beta-cyclodextrin.

PubMed

Ghorab, Mohamed K; Adeyeye, Moji Christianah

2003-08-01

The objectives of this study were to evaluate the bioavailability of cogranulated and oven-dried ibuprofen (IBU) and beta-cyclodextrin (betaCD), in comparison to a physical mixture, and to examine the effect of endogenous bile on the bioavailability of the drug. In vitro dissolution studies were performed using USP type 2 apparatus. The granules and physical mixture were administered perorally in a crossover fashion, to male Wistar bile duct-nonligated rats. The granules were also perorally administered to bile duct-ligated rats. Blood samples were taken at different time intervals and the plasma analyzed for IBU. Dissolution of granules was faster than the physical mixture due to faster IBU-betaCD complex formation in solution from the former than the latter. The in vivo study showed that C(max), AUC(0-8), and the absolute bioavailability for the granules (49.0 microg/mL, 57.0 h x microg/mL and 80.6%, respectively) were almost one and half times that of the physical mixture (32.2 microg/mL, 38.4 h x microg/mL and 53.1%, respectively). However, in bile duct-ligated rats, lower C(max) and AUC(0-8) (15.9 microg/mL and 14.4 h x microg/mL, respectively) were obtained for the granules. Phase solubility study of IBU in an aqueous betaCD solution in the presence of the bile salt (sodium cholate), showed an increase in the solubility of IBU. Moreover, the stability constant value for the IBU-betaCD complex was also found to decrease as the sodium cholate concentration increased. These results indicated that the enhancement in the bioavailability of IBU was due to faster in-solution complex formation, and micelllar solubilization by the bile salt. Copyright 2003 Wiley-Liss, Inc.

Diet, plasma levels of beta-carotene and alpha-tocopherol, and risk of malignant melanoma.

PubMed

Stryker, W S; Stampfer, M J; Stein, E A; Kaplan, L; Louis, T A; Sober, A; Willett, W C

1990-04-01

Dietary intake and the plasma levels of retinol, alpha-tocopherol, lycopene, alpha-carotene, and beta-carotene for 204 cases with malignant melanoma were compared with those of 248 controls. Cases and controls were patients 18 years of age or older making their first visit to a dermatology subspecialty clinic for pigmented lesions from July 1, 1982 to September 1, 1985. Intakes of nutrients were estimated using a semiquantitative food frequency questionnaire. No significant associations with malignant melanoma were observed for higher plasma levels of lycopene, retinol, or alpha-carotene in logistic regression analyses after controlling for age, sex, plasma lipids, and known constitutional risk factors (hair color and ability to tan). In similar models, the odds ratio comparing the highest with the lowest quintile was 0.9 (95% confidence interval (CI) 0.5-1.5) for plasma beta-carotene, 0.7 (95% CI 0.5-1.3) for plasma alpha-tocopherol, 0.7 (95% CI 0.4-1.2) for carotene intake, and 0.7 (95% CI 0.4-1.3) for total vitamin E intake. A trend toward reduced risk of melanoma was observed for increasing intake of iron (not including supplements); this was related to the more frequent consumption of baked goods, such as cake, among controls. Alcohol consumption was positively associated with risk of melanoma (chi for trend = 2.1, p = 0.03); the odds ratio for consumption of over 10 g/day compared with persons with no alcohol intake was 1.8 (95% CI 1.0-3.3).

Effect of long-term exposure to pesticides on plasma esterases from plastic greenhouse workers.

PubMed

Hernández, Antonio; Gómez, M Amparo; Pena, Gloria; Gil, Fernando; Rodrigo, Lourdes; Villanueva, Enrique; Pla, Antonio

2004-07-23

Previous reports in animals considered beta-glucuronidase activity as a novel biomarker of anticholinesterase (organophosphates and carbamates) pesticides exposure. Acid phosphatase activity was also shown to increase after organophosphates exposure. In addition, there is evidence that the paraoxonase status influences sensitivity to specific pesticides. In this study, activities of beta-glucuronidase, acid phosphatase, cholinesterase, and paraoxonase were measured in plasma from plastic greenhouse workers exposed over the long term to different pesticides, including organophosphates and carbamates, in order to evaluate the potential chronic toxicity of pesticides at occupational level. Our results show that activities of paraoxonase and cholinesterase were decreased in applicators of pesticides compared to non-applicators. Likewise, it was found that activities of beta-glucuronidase and acid phosphatase were associated with pesticide exposure in humans, and that both biochemical parameters were related to each other. Interestingly, the paraoxonase B allele (phenotyped in plasma) was associated with a higher risk of inhibition of cholinesterase activity above a 25% level, which supports the hypothesis that paraoxonase phenotypes are associated with susceptibility of humans to anticholinesterase pesticides toxicity. Copyright Taylor and Francis Inc.

The phosphatidylinositol 3-kinase inhibitor, wortmannin, inhibits insulin-induced activation of phosphatidylcholine hydrolysis and associated protein kinase C translocation in rat adipocytes.

PubMed Central

Standaert, M L; Avignon, A; Yamada, K; Bandyopadhyay, G; Farese, R V

1996-01-01

We questioned whether phosphatidylinositol 3-kinase (PI 3-kinase) and protein kinase C (PKC) function as interrelated signalling mechanisms during insulin action in rat adipocytes. Insulin rapidly activated a phospholipase D that hydrolyses phosphatidylcholine (PC), and this activation was accompanied by increases in diacylglycerol and translocative activation of PKC-alpha and PKC-beta in the plasma membrane. Wortmannin, an apparently specific PI 3-kinase inhibitor, inhibited insulin-stimulated, phospholipase D-dependent PC hydrolysis and subsequent translocation of PKC-alpha and PKC-beta to the plasma membrane. Wortmannin did not inhibit PKC directly in vitro, or the PKC-dependent effects of phorbol esters on glucose transport in intact adipocytes. The PKC inhibitor RO 31-8220 did not inhibit PI 3-kinase directly or its activation in situ by insulin, but inhibited both insulin-stimulated and phorbol ester-stimulated glucose transport. Our findings suggest that insulin acts through PI 3-kinase to activate a PC-specific phospholipase D and causes the translocative activation of PKC-alpha and PKC-beta in plasma membranes of rat adipocytes. PMID:8611143

The phosphatidylinositol 3-kinase inhibitor, wortmannin, inhibits insulin-induced activation of phosphatidylcholine hydrolysis and associated protein kinase C translocation in rat adipocytes.

PubMed

Standaert, M L; Avignon, A; Yamada, K; Bandyopadhyay, G; Farese, R V

1996-02-01

We questioned whether phosphatidylinositol 3-kinase (PI 3-kinase) and protein kinase C (PKC) function as interrelated signalling mechanisms during insulin action in rat adipocytes. Insulin rapidly activated a phospholipase D that hydrolyses phosphatidylcholine (PC), and this activation was accompanied by increases in diacylglycerol and translocative activation of PKC-alpha and PKC-beta in the plasma membrane. Wortmannin, an apparently specific PI 3-kinase inhibitor, inhibited insulin-stimulated, phospholipase D-dependent PC hydrolysis and subsequent translocation of PKC-alpha and PKC-beta to the plasma membrane. Wortmannin did not inhibit PKC directly in vitro, or the PKC-dependent effects of phorbol esters on glucose transport in intact adipocytes. The PKC inhibitor RO 31-8220 did not inhibit PI 3-kinase directly or its activation in situ by insulin, but inhibited both insulin-stimulated and phorbol ester-stimulated glucose transport. Our findings suggest that insulin acts through PI 3-kinase to activate a PC-specific phospholipase D and causes the translocative activation of PKC-alpha and PKC-beta in plasma membranes of rat adipocytes.

Determination of the Alfvén Speed and Plasma-beta Using the Seismology of Sunspot Umbra

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cho, I.-H.; Moon, Y.-J.; Nakariakov, V. M.

For 478 centrally located sunspots observed in the optical continuum with Solar Dynamics Observatory /Helioseismic Magnetic Imager, we perform seismological diagnostics of the physical parameters of umbral photospheres. The new technique is based on the theory of slow magnetoacoustic waves in a non-isothermally stratified photosphere with a uniform vertical magnetic field. We construct a map of the weighted frequency of three-minute oscillations inside the umbra and use it for the estimation of the Alfvén speed, plasma-beta, and mass density within the umbra. We find the umbral mean Alfvén speed ranges between 10.5 and 7.5 km s{sup −1} and is negativelymore » correlated with magnetic field strength. The umbral mean plasma-beta is found to range approximately between 0.65 and 1.15 and does not vary significantly from pores to mature sunspots. The mean density ranges between (1–6) × 10{sup −4} kg m{sup −3} and shows a strong positive correlation with magnetic field strength.« less

Metabolism of plasma cholesterol and lipoprotein parameters are related to a higher degree of insulin sensitivity in high HDL-C healthy normal weight subjects.

PubMed

Leança, Camila C; Nunes, Valéria S; Panzoldo, Natália B; Zago, Vanessa S; Parra, Eliane S; Cazita, Patrícia M; Jauhiainen, Matti; Passarelli, Marisa; Nakandakare, Edna R; de Faria, Eliana C; Quintão, Eder C R

2013-11-22

We have searched if plasma high density lipoprotein-cholesterol (HDL-C) concentration interferes simultaneously with whole-body cholesterol metabolism and insulin sensitivity in normal weight healthy adult subjects. We have measured the activities of several plasma components that are critically influenced by insulin and that control lipoprotein metabolism in subjects with low and high HDL-C concentrations. These parameters included cholesteryl ester transfer protein (CETP), phospholipid transfer protein (PLTP), lecithin cholesterol acyl transferase (LCAT), post-heparin lipoprotein lipase (LPL), hepatic lipase (HL), pre-beta-₁HDL, and plasma sterol markers of cholesterol synthesis and intestinal absorption. In the high-HDL-C group, we found lower plasma concentrations of triglycerides, alanine aminotransferase, insulin, HOMA-IR index, activities of LCAT and HL compared with the low HDL-C group; additionally, we found higher activity of LPL and pre-beta-₁HDL concentration in the high-HDL-C group. There were no differences in the plasma CETP and PLTP activities. These findings indicate that in healthy hyperalphalipoproteinemia subjects, several parameters that control the metabolism of plasma cholesterol and lipoproteins are related to a higher degree of insulin sensitivity.

Correlations between Fruit, Vegetables, Fish, Vitamins, and Fatty Acids Estimated by Web-Based Nonconsecutive Dietary Records and Respective Biomarkers of Nutritional Status.

PubMed

Lassale, Camille; Castetbon, Katia; Laporte, François; Deschamps, Valérie; Vernay, Michel; Camilleri, Géraldine M; Faure, Patrice; Hercberg, Serge; Galan, Pilar; Kesse-Guyot, Emmanuelle

2016-03-01

It is of major importance to measure the validity of self-reported dietary intake using web-based instruments before applying them in large-scale studies. This study aimed to validate self-reported intake of fish, fruit and vegetables, and selected micronutrient intakes assessed by a web-based self-administered dietary record tool used in the NutriNet-Santé prospective cohort study, against the following concentration biomarkers: plasma beta carotene, vitamin C, and n-3 polyunsaturated fatty acids. One hundred ninety-eight adult volunteers (103 men and 95 women, mean age=50.5 years) were included in the protocol: they completed 3 nonconsecutive-day dietary records and two blood samples were drawn 3 weeks apart. The study was conducted in the area of Paris, France, between October 2012 and May 2013. Reported fish, fruit and vegetables, and selected micronutrient intakes and plasma beta carotene, vitamin C, and n-3 polyunsaturated fatty acid levels were compared. Simple and adjusted Spearman's rank correlation coefficients were estimated after de-attenuation for intra-individual variation. Regarding food groups in men, adjusted correlations ranged from 0.20 for vegetables and plasma vitamin C to 0.49 for fruits and plasma vitamin C, and from 0.40 for fish and plasma c20:5 n-3 (eicosapentaenoic acid [EPA]) to 0.55 for fish and plasma c22:6 n-3 (docosahexaenoic acid). In women, correlations ranged from 0.13 (nonsignificant) for vegetables and plasma vitamin C to 0.41 for fruits and vegetables and plasma beta carotene, and from 0.27 for fatty fish and EPA to 0.54 for fish and EPA+docosahexaenoic acid. Regarding micronutrients, adjusted correlations ranged from 0.36 (EPA) to 0.58 (vitamin C) in men and from 0.32 (vitamin C) to 0.38 (EPA) in women. The findings suggest that three nonconsecutive web-based dietary records provide reasonable estimates of true intake of fruits, vegetables, fish, beta carotene, vitamin C, and n-3 fatty acids. Along with other validation studies, this study shows acceptable validity of using such diet-assessment methods in large epidemiologic surveys and broadens new perspectives for epidemiology. Copyright © 2016 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Quantitative Assessment of Proliferative Effects of Oral Vanadium on Pancreatic Islet Volumes and Beta Cell Numbers of Diabetic Rats

PubMed Central

Pirmoradi, Leila; Noorafshan, Ali; Safaee, Akbar; Dehghani, Gholam Abbas

2016-01-01

Background: Oral vanadyl sulfate (vanadium) induces normoglycemia, proliferates beta cells and prevents pancreatic islet atrophy in streptozotocin-induced diabetic rats. Soteriological method is used to quantitate the proliferative effects of vanadium on beta-cell numbers and islet volumes of normal and diabetic rats. Methods: Adult male Sprague-Dawley rats were made diabetic with intravenous streptozotocin injection (40 mg/kg). Normal and diabetic rats were divided into four groups. While control normal and diabetic (CD) groups used water, vanadium-treated normal (VTN) and diabetic (VTD) groups used solutions containing vanadyl sulfate (0.5-1 mg/mL, VOSO4+5H2O). Tail blood samples were used to measure blood glucose (BG) and plasma insulin. Two months after treatment, rats were sacrificed, pancreata prepared, and stereology method was used to quantitatively evaluate total beta cell numbers (TBCN) and total islet volumes (TISVOL). Results: Normoglycemia persisted in VTN with significantly decreased plasma insulin (0.190.08 vs. 0.970.27 ng/dL, P<0.002). The respective high BG (53249 vs. 14446 mg/dL, P<0.0001) and reduced plasma insulin (0.260.15 vs. 0.540.19 ng/dL, P<0.002) seen in CD were reversed in VTD during vanadium treatment or withdrawal. While the induction of diabetes, compared to their control, significantly decreased TISVOL (1.90.2 vs. 3.030.6 mm3, P<0.003) and TBCN (0.990.1 vs. 3.20.2 x 106, P<0.003), vanadium treatment significantly increased TISVOL (2.90.8 and 4.071.0 mm3, P<0.003) and TBCN (1.50.3 and 3.80.6 x 106, P<0.03). Conclusion: Two-month oral vanadium therapy in STZ-diabetic rats ameliorated hyperglycemia by partially restoring plasma insulin. This action was through proliferative actions of vanadium in preventing islet atrophy by increasing beta-cell numbers. PMID:26459400

Relationships among the behavioral, noradrenergic, and pituitary-adrenal responses to interleukin-1 and the effects of indomethacin.

PubMed

Wieczorek, Marek; Dunn, Adrian J

2006-09-01

Peripheral administration of interleukin-1 (IL-1) is known to activate the hypothalamo-pituitary-adrenal axis (HPA axis) and brain noradrenergic systems. We studied the relationship between these responses using in vivo microdialysis to assess the release of hypothalamic norepinephrine (NE), while simultaneously sampling blood for ACTH and corticosterone, and monitoring body temperature and behavior in freely moving rats. Rats were implanted with microdialysis probes in the medial hypothalamus, with intravenous catheters, and with telethermometers in the abdomen. Each rat was injected with saline and IL-1beta (1 microg ip) in random order, monitoring microdialysate NE, body temperature and plasma ACTH and corticosterone for 2-4 h after injection. Saline injections were followed by transient increases in microdialysate NE and in plasma ACTH and corticosterone. IL-1beta injections resulted in prolonged elevations of microdialysate NE, as well as plasma ACTH and corticosterone, and body temperature. IL-1beta also induced shivering and a prolonged depression of locomotor activity. Pretreatment with indomethacin (10 mg/kg sc) prevented the IL-1beta-induced increases in body temperature and the apparent increase in hypothalamic NE release, but only attenuated the IL-1beta-induced shivering and the increase in plasma ACTH. The results indicate a close temporal relationship between the release of NE and HPA axis activation. Such a relationship is also supported by the similar effects of indomethacin pretreatment on NE and ACTH. The shivering is likely involved in the increase in body temperature, but indomethacin only attenuated the shivering while it blocked the fever. However, the effects of indomethacin clearly indicate that neither the increase in body temperature nor the increase in hypothalamic NE release was essential for HPA axis activation. These results suggest that hypothalamic NE is involved in the IL-1-induced HPA axis activation, but that this is not the only mechanism by which the HPA axis is activated by intraperitoneally injected IL-1.

Nonlinear dynamics of the 3D FMS and Alfven wave beams propagating in plasma of ionosphere and magnetosphere

NASA Astrophysics Data System (ADS)

Belashov, Vasily

We study the formation, structure, stability and dynamics of the multidimensional soliton-like beam structures forming on the low-frequency branch of oscillation in the ionospheric and magnetospheric plasma for cases when beta=4pinT/B(2) <<1 and beta>1. In first case with the conditions omega>{k_{yz}}(2,) v_{x}$<

Metabolomic profiling of amino acids and beta-cell function relative to insulin sensitivity in youth

USDA-ARS?s Scientific Manuscript database

In longitudinal studies of adults, elevated amino acid (AA) concentrations predicted future type 2 diabetes mellitus (T2DM). The aim of the present investigation was to examine whether increased plasma AA concentrations are associated with impaired beta-cell function relative to insulin sensitivity ...

Divergent expression of 11beta-hydroxysteroid dehydrogenase and 11beta-hydroxylase genes between male morphs in the central nervous system, sonic muscle and testis of a vocal fish.

PubMed

Arterbery, Adam S; Deitcher, David L; Bass, Andrew H

2010-05-15

The vocalizing midshipman fish, Porichthys notatus, has two male morphs that exhibit alternative mating tactics. Only territorial males acoustically court females with long duration (minutes to >1h) calls, whereas sneaker males attempt to steal fertilizations. During the breeding season, morph-specific tactics are paralleled by a divergence in relative testis and vocal muscle size, plasma levels of the androgen 11-ketotestosterone (11KT) and the glucocorticoid cortisol, and mRNA expression levels in the central nervous system (CNS) of the steroid-synthesizing enzyme aromatase (estrogen synthase). Here, we tested the hypothesis that the midshipman's two male morphs would further differ in the CNS, as well as in the testis and vocal muscle, in mRNA abundance for the enzymes 11beta-hydroxylase (11betaH) and 11beta-hydroxysteroid dehydrogenase (11betaHSD) that directly regulate both 11KT and cortisol synthesis. Quantitative real-time PCR demonstrated male morph-specific profiles for both enzymes. Territorial males had higher 11betaH and 11betaHSD mRNA levels in testis and vocal muscle. By contrast, sneaker males had the higher CNS expression, especially for 11betaHSD, in the region containing an expansive vocal pacemaker circuit that directly determines the temporal attributes of natural calls. We propose for territorial males that higher enzyme expression in testis underlies its greater plasma 11KT levels, which in vocal muscle provides both gluconeogenic and androgenic support for its long duration calling. We further propose for sneaker males that higher enzyme expression in the vocal CNS contributes to known cortisol-specific effects on its vocal physiology. Copyright 2010 Elsevier Inc. All rights reserved.

Beta-catenin interacts with low-molecular-weight protein tyrosine phosphatase leading to cadherin-mediated cell-cell adhesion increase.

PubMed

Taddei, Maria Letizia; Chiarugi, Paola; Cirri, Paolo; Buricchi, Francesca; Fiaschi, Tania; Giannoni, Elisa; Talini, Doriana; Cozzi, Giacomo; Formigli, Lucia; Raugei, Giovanni; Ramponi, Giampietro

2002-11-15

Beta-catenin plays a dual role as a major constituent of cadherin-based adherens junctions and also as a transcriptional coactivator. In normal ephitelial cells, at adherens junction level, beta-catenin links cadherins to the actin cytoskeleton. The structure of adherens junctions is dynamically regulated by tyrosine phosphorylation. In particular, cell-cell adhesion can be negatively regulated through the tyrosine phosphorylation of beta-catenin. Furthermore, the loss of beta-catenin-cadherin association has been correlated with the transition from a benign tumor to an invasive, metastatic cancer. Low-molecular-weight protein tyrosine phosphatase (LMW-PTP) is a ubiquitous PTP implicated in the regulation of mitosis and cytoskeleton rearrangement. Here we demonstrate that the amount of free cytoplasmic beta-catenin is decreased in NIH3T3, which overexpresses active LMW-PTP, and this results in a stronger association between cadherin complexes and the actin-based cytoskeleton with respect to control cells. Confocal microscopy analysis shows that beta-catenin colocalizes with LMW-PTP at the plasma membrane. Furthermore, we provide evidence that beta-catenin is able to associate with LMW-PTP both in vitro and in vivo. Moreover, overexpression of active LMW-PTP strongly potentiates cadherin-mediated cell-cell adhesion, whereas a dominant-negative form of LMW-PTP induces the opposite phenotype, both in NIH3T3 and in MCF-7 carcinoma cells. On the basis of these results, we propose that the stability of cell-cell contacts at the adherens junction level is positively influenced by LMW-PTP expression, mainly because of the beta-catenin and LMW-PTP interaction at the plasma membrane level with consequent dephosphorylation.

Alteration of metabolite profiling by cold atmospheric plasma treatment in human myeloma cells.

PubMed

Xu, Dehui; Xu, Yujing; Ning, Ning; Cui, Qingjie; Liu, Zhijie; Wang, Xiaohua; Liu, Dingxin; Chen, Hailan; Kong, Michael G

2018-01-01

Despite new progress of chemotherapy in multiple myeloma (MM) clinical treatment, MM is still a refractory disease and new technology is needed to improve the outcomes and prolong the survival. Cold atmospheric plasma is a rapidly developed technology in recent years, which has been widely applied in biomedicine. Although plasma could efficiently inactivate various tumor cells, the effects of plasma on tumor cell metabolism have not been studied yet. In this study, we investigated the metabolite profiling of He plasma treatment on myeloma tumor cells by gas-chromatography time-of-flight (GC-TOF) mass-spectrometry. Meanwhile, by bioinformatic analysis such as GO and KEGG analysis we try to figure out the metabolism pathway that was significantly affected by gas plasma treatment. By GC-TOF mass-spectrometry, 573 signals were detected and evaluated using PCA and OPLS-DA. By KEGG analysis we listed all the differential metabolites and further classified into different metabolic pathways. The results showed that beta-alanine metabolism pathway was the most significant change after He gas plasma treatment in myeloma cells. Besides, propanoate metabolism and linoleic acid metabolism should also be concerned during gas plasma treatment of cancer cells. Cold atmospheric plasma treatment could significantly alter the metabolite profiling of myeloma tumor cells, among which, the beta-alanine metabolism pathway is the most susceptible to He gas plasma treatment.

Comment on "Hydrogen Balmer beta: The separation between line peaks for plasma electron density diagnostics and self-absorption test"

NASA Astrophysics Data System (ADS)

Gautam, Ghaneshwar; Surmick, David M.; Parigger, Christian G.

2015-07-01

In this letter, we present a brief comment regarding the recently published paper by Ivković et al., J Quant Spectrosc Radiat Transf 2015;154:1-8. Reference is made to previous experimental results to indicate that self absorption must have occurred; however, when carefully considering error propagation, both widths and peak-separation predict electron densities within the error margins. Yet the diagnosis method and the presented details on the use of the hydrogen beta peak separation are viewed as a welcomed contribution in studies of laser-induced plasma.

Beta > 1 Plasmas

NASA Astrophysics Data System (ADS)

Jones, Robert

2017-10-01

I have suggested that fusion researchers should put more effort into the study of beta > 1 or wall confined plasmas. Magneto-Inertial Fusion and Magnetized Target Fusion projects at Los Alamos National Laboratory are recent examples of this sort of work. Unfortunately, theoretical studies of such systems may be employing overly optimistic models of the magnetic thermal insulation. One might well expect such systems to have stochastic field lines. If that is the case then we might want to employ turbulent thermal insulation as suggested in my papers: Current Science, pg 991, 1988 and Bull. Am. Phys. Soc., Nov. 4, 2009.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nagino, Ko; Yokozawa, Junji; Sasaki, Yu

Highlights: Black-Right-Pointing-Pointer Insulin secretion was increased during the OGTT or IVGTT in mesenteric lymph duct-ligated rats. Black-Right-Pointing-Pointer Proliferation of islet {beta}-cells was upregulated in lymph duct-ligated rats. Black-Right-Pointing-Pointer Mesenteric lymph duct flow has a role in glucose metabolism. -- Abstract: Background and aims: It has been suggested that intestinal lymph flow plays an important role in insulin secretion and glucose metabolism after meals. In this study, we investigated the influence of ligation of the mesenteric lymph duct on glucose metabolism and islet {beta}-cells in rats. Methods: Male Sprague-Dawley rats (10 weeks old) were divided into two groups: one underwent ligationmore » of the mesenteric lymph duct above the cistern (ligation group), and the other underwent a sham operation (sham group). After 1 and 2 weeks, fasting plasma concentrations of glucose, insulin, triglyceride, glucose-dependent insulinotropic polypeptide (GIP), and the active form of glucagon-like peptide-1 (GLP-1) were measured. At 2 weeks after the operation, the oral glucose tolerance test (OGTT) and intravenous glucose tolerance test (IVGTT) were performed. After the rats had been sacrificed, the insulin content of the pancreas was measured and the proliferation of {beta}-cells was assessed immunohistochemically using antibodies against insulin and Ki-67. Results: During the OGTT, the ligation group showed a significant decrease in the plasma glucose concentration at 120 min (p < 0.05) and a significant increase in the plasma insulin concentration by more than 2-fold at 15 min (p < 0.01). On the other hand, the plasma GIP concentration was significantly decreased at 60 min (p < 0.01) in the ligated group, while the active form of GLP-1 showed a significantly higher level at 90 min (1.7-fold; p < 0.05) and 120 min (2.5-fold; p < 0.01). During the IVGTT, the plasma insulin concentration in the ligation group was significantly higher at 2 min (more than 1.4-fold; p < 0.05). Immunohistochemistry showed that the ratios of {beta}-cell area/acinar cell area and {beta}-cell area/islet area, and also {beta}-cell proliferation, were significantly higher in the ligation group than in the sham group (p < 0.05, p < 0.01 and p < 0.01, respectively). The insulin content per unit wet weight of pancreas was also significantly increased in the ligation group (p < 0.05). Conclusions: In rats with ligation of the mesenteric lymph duct, insulin secretion during the OGTT or IVGTT was higher, and the insulin content and {beta}-cell proliferation in the pancreas were also increased. Our data show that mesenteric lymph duct flow has a role in glucose metabolism.« less

The third intracellular loop and carboxyl tail of neurokinin 1 and 3 receptors determine interactions with beta-arrestins.

PubMed

Schmidlin, Fabien; Roosterman, Dirk; Bunnett, Nigel W

2003-10-01

Tachykinins interact with three neurokinin receptors (NKRs) that are often coexpressed by the same cell. Cellular responses to tachykinins depend on the NKR subtype that is activated. We compared the colocalization of NK1R and NK3R with beta-arrestins 1 and 2, which play major roles in receptor desensitization, endocytosis, and signaling. In cells expressing NK1R, the selective agonist Sar-Met-substance P induced rapid translocation of beta-arrestins 1 and 2 from the cytosol to the plasma membrane and then endosomes, indicative of interaction with both isoforms. In contrast, the NK3R interacted transiently with only beta-arrestin 2 at the plasma membrane. Despite these differences, both NK1R and NK3R similarly desensitized, internalized, and activated MAP kinases. Because interactions with beta-arrestins can explain differences in the rate of receptor resensitization, we compared resensitization of agonist-induced Ca2+ mobilization. The NK1R resensitized greater than twofold more slowly than the NK3R. Replacement of intracellular loop 3 and the COOH tail of the NK1R with comparable domains of the NK3R diminished colocalization of the NK1R with beta-arrestin 1 and accelerated resensitization to that of the NK3R. Thus loop 3 and the COOH tail specify colocalization of the NK1R with beta-arrestin 1 and determine the rate of resensitization.

The effect of plasma beta on high-n ballooning stability at low magnetic shear

NASA Astrophysics Data System (ADS)

Connor, J. W.; Ham, C. J.; Hastie, R. J.

2016-08-01

An explanation of the observed improvement in H-mode pedestal characteristics with increasing core plasma pressure or poloidal beta, {β\\text{pol}} , as observed in MAST and JET, is sought in terms of the impact of the Shafranov shift, {{Δ }\\prime} , on ideal ballooning MHD stability. To illustrate this succinctly, a self-consistent treatment of the low magnetic shear region of the ‘s-α ’ stability diagram is presented using the large aspect ratio Shafranov equilibrium, but enhancing both α and {{Δ }\\prime} so that they compete with each other. The method of averaging, valid at low s, is used to simplify the calculation and demonstrates how α , {{Δ }\\prime} , plasma shaping and ‘average favourable curvature’ all contribute to stability.

Specific radioimmunoassay for human. beta. -lipotropin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jeffcoate, W.J.; Rees, L.H.; Lowry, P.J.

1978-07-01

A homologous RIA for human ..beta..-lipotropin (..beta..hLPH) has been developed. At a final dilution of 1:24,000, the antiserum employed shows cross-reaction with ..beta..hLPH but none with human ..beta..-MSH (..beta..hMSH), and it is concluded that the antigenic determinant lies within the N-terminal 1 to 36 region of ..beta..hLPH. With extraction of 3-ml plasma samples, the assay is sufficiently sensitive to measure circulating ..beta..hLPH levels in normal individuals at 0900 h (25 to 200 pg/ml). There is a circadian variation with levels falling to (less than 20 to 80 pg/ml) at 2300 h. ..beta..hLPH levels rise after metyrapone and after insulin-induced hypoglycemia,more » and fall after administration of dexamethasone. In patients with a variety of diseases of the pituitary-adrenal axis, levels of ..beta..hLPH follow immunoreactive ACTH levels, although the two are not always secreted on a 1:1 molar basis.« less

Hematologic, cytochemical, ultrastructural, and molecular findings of Hepatozoon-infected flat-headed cats (Prionailurus planiceps).

PubMed

Salakij, Chaleow; Salakij, Jarernsak; Narkkong, Nual-Anong; Sirinarumitr, Theerapol; Pattanarangsan, Rattapan

2008-03-01

The flat-headed cat (Prionailurus planiceps) is a small wild cat of Southeast Asia and is considered extremely endangered. Little is known about the hematologic values, blood cell morphology, or hemoparasites of this species in relation to other Felidae. The objective of this study was to report basic hematologic values and describe the light microscopic, cytochemical, and ultrastructural characteristics of blood cells in 2 wild-caught flat-headed cats. In addition, molecular analysis was done of a Hepatozoon organism found in the neutrophils of both cats. Blood samples were collected into EDTA from the cephalic vein. A CBC, manual differential count, manual reticulocyte count, cytochemical stains (Sudan black B [SBB], alpha-naphthyl acetate esterase [ANAE], and beta-glucuronidase), and scanning and transmission electron microscopy were done using standard methods. HCT was slightly lower and reticulocyte counts and red cell distribution width were higher than the expected values for other species of cats. Hepatozoon organisms were found in the cytoplasm of neutrophils in both cats, but the number of infected neutrophils was very low (1%-2%). Neutrophils stained strongly positive for SBB, but were negative for ANAE and beta-glucuronidase. Hepatozoon-infected neutrophils were negative for SBB, but focally positive for ANAE and beta-glucuronidase. By transmission electron microscopy, gamonts of Hepatozoon sp were observed in neutrophils, and rarely free in plasma. Infected neutrophils had fewer specific granules and more mitochondria compared with noninfected neutrophils. PCR products of partial 18S rRNA revealed that the isolate of Hepatozoon in the flat-headed cats was closely related to that of the frog Hepatozoon sp. These results add to our understanding of hematologic values and blood cell morphology in Hepatozoon-infected flat-headed cats as well as the molecular analysis of the Hepatozoon organism, and may be useful for the health management and evaluation of hemoparasitic disease in this species.

Carotenoids as protection against disability in older persons.

PubMed

Lauretani, Fulvio; Semba, Richard D; Bandinelli, Stefania; Dayhoff-Brannigan, Margaret; Lauretani, Fabrizio; Corsi, Anna Maria; Guralnik, Jack M; Ferrucci, Luigi

2008-06-01

The purpose was to examine the relationship of total plasma carotenoids, an indicator of fruit and vegetable intake, with walking speed and severe walking disability in older adults. Nine hundred twenty-eight men and women aged 65 to 102 years from the Invecchiare in Chianti (Aging in the Chianti Area [InCHIANTI]) study, a population-based cohort in Tuscany, Italy, were studied. Plasma carotenoids were measured at enrollment (1998-2000), and walking speed over 4 meters and 400 meters distance were assessed at enrollment and 6 years later (2004-2006). At enrollment, 85 of 928 (9.2%) participants had severe walking disability (defined as being unable to walk or having a walking speed at the 4-meter walking test < 0.4 m/sec). After adjusting for potential confounders, participants with high total plasma carotenoids were significantly less likely to have prevalent severe walking disability (odds ration [OR] 0.59, 95% confidence interval [CI] 0.38-0.90, p = 0.01) and had higher walking speed over 4 meters (beta = 0.024, standard error [SE] = 0.011, p = 0.03) and over 400 meters (beta = 0.019, SE = 0.010, p = 0.04). Of 621 participants without severe walking disability at enrollment who were seen 6 years later, 68 (11.0%) developed severe walking disability. After adjusting for potential confounders, higher total plasma carotenoids were associated with a significantly lower risk of developing severe walking disability (OR 0.51, 95% CI 0.30-0.86, p = 0.01) and were associated with a less steep decline in 4-meter walking speed over a 6-year follow-up (n = 579; beta = 0.026, SE = 0.012, p = 0.03) and with lower incidence rates of being unable to successfully complete the 400-meter walking test at the 6-year follow-up visit (beta = -0.054, SE = 0.03, p = 0.04). High plasma carotenoids concentrations may be protective against the decline in walking speed and the development of severe walking disability in older adults.

Vitamin E supplement improves erythrocyte membrane fluidity of thalassemia: an ESR spin labeling study.

PubMed

Sutipornpalangkul, Werasak; Morales, Noppawan Phumala; Unchern, Supeenun; Sanvarinda, Yupin; Chantharaksri, Udom; Fucharoen, Suthat

2012-01-01

Beta-thalassemia/Hemoglobin E (beta-thal/Hb E) is prevalent in Thailand. The imbalance of globin chains in red blood cells is the primary cause of this anemic disease. The excess alpha-globin in beta-thal/Hb E causes typical damage(s) to membrane of erythroblasts and erythrocytes. By using three paramagnetic labeled compounds (5-, 12-, and 16-spin labeled stearic acids, SLS), the changes of the molecular motion in the lipid bilayer of thalassemic RBCs that have structural modification can be detected. to investigate erythrocyte membrane fluidity and the effect of vitamin E treatment in beta-thalassemia/Hemoglobin E patients by using spin labeling techniques. The erythrocyte membrane fluidity was investigated in nine splenectomized and five non-splenectomized beta-thalassemia/hemoglobin E (beta-thal/Hb E) patients using EPR spin labeling techniques. To determine the effect of vitamin E on erythrocyte membrane fluidity, only the splenectomized patients were enrolled. Patients were divided into two groups. The first group received 350 mg vitamin E daily for a period of 1 month (n = 5) and the second group received placebo for an equal period (n = 4). Three paramagnetic fatty acid, 5-, 12-, and 16-doxyl stearic acids, (5-, 12- and 16-DS) were used to label phospholipids layer near both the surface (5-DS) and the deeper hydrophobic region of membrane (12-and 16-DS). Lipid peroxidation (TBARs) was measured using a colorimetric method. Vitamin E was measured with high performance liquid chromatography (HPLC). Significantly higher values of erythrocyte membrane fluidity were revealed with 12-, 16-DS in splenectomized patients, as compared with non-splenectomized patients and normal subjects. In 3-thal/Hb E patients, fluidity values, both outer hyperfine splitting (2T(//)) and order parameter (S) of 12-DS showed inverse correlation with serum TBARs. There was no significant difference between the fluidity values measured with 5-DS. After vitamin E supplementation, the erythrocyte membrane fluidity was decreased in almost all patients. In contrast to the vitamin E supplementation group, increased erythrocyte membrane fluidity was demonstrated in the placebo group. Vitamin E supplementation also had effect on other clinical parameters such as increased plasma vitamin E, decreased serum TBARs and no change in hemoglobin. The present results suggested the abnormal motion of lipid in the deeper phospholipids region of membrane. In addition, vitamin E supplementation may have a role in the prevention of erythrocyte membrane damage of these patients.

The effect of a low-carbohydrate diet on performance, hormonal and metabolic responses to a 30-s bout of supramaximal exercise.

PubMed

Langfort, J; Zarzeczny, R; Pilis, W; Nazar, K; Kaciuba-Uścitko, H

1997-01-01

The aim of this study was to find out whether a low-carbohydrate diet (L-CHO) affects: (1) the capacity for all-out anaerobic exercise, and (2) hormonal and metabolic responses to this type of exercise. To this purpose, eight healthy subjects underwent a 30-s bicycle Wingate test preceded by either 3 days of a controlled mixed diet (130 kJ/kg of body mass daily, 50% carbohydrate, 30% fat, 20% protein) or 3 days of an isoenergetic L-CHO diet (up to 5% carbohydrate, 50% fat, 45% protein) in a randomized order. Before and during 1 h after the exercise venous blood samples were taken for measurement of blood lactate (LA), beta-hydroxybutyrate (beta-HB), glucose, adrenaline (A), noradrenaline (NA) and insulin levels. Oxygen consumption (VO2) was also determined. It was found that the L-CHO diet diminished the mean power output during the 30-s exercise bout [533 (7) W vs 581 (7) W, P < 0.05] without changing the maximal power attained during the first or second 5-s interval of the exercise. In comparison with the data obtained after the consumption of a mixed diet, after the consumption of a L-CHO diet resting plasma concentrations of beta-HB [2.38 (0.18) vs 0.23 (0.01) mmol x l(-1), P < 0.001] and NA [4.81 (0.68) vs 2.2 (0.31) nmol x l(-1), P < 0.05] were higher, while glucose [4.6 (0.1) vs 5.7 (0.2) mmol x l(-1), P < 0.05] and insulin concentrations [11.9 (0.9) vs 21.8 (1.8) mU x l(-1)] were lower. The 1-h post-exercise excess of VO2 [9.1 (0.25) vs 10.6 (0.25) 1, P < 0.05], and blood LA measured 3 min after the exercise [9.5 (0.4) vs 10.6 (0.5) mmol x l(-1), P < 0.05] were lower following the L-CHO treatment, whilst plasma NA and A concentrations reached higher values [2.24 (0.40) vs 1.21 (0.13) nmol x l(-1) and 14.30 (1.41) vs 8.20 (1.31) nmol x l(-1), P < 0.01, respectively]. In subjects on the L-CHO diet, the plasma beta-HB concentration decreased quickly after exercise, attaining approximately 30% of the pre-exercise value within 60 min, while insulin and glucose levels were elevated. The main conclusions of this study are: (1) a L-CHO diet is detrimental to anaerobic work capacity, possibly because of a reduced muscle glycogen store and decreased rate of glycolysis; (2) reduced carbohydrate intake for 3 days enhances activity of the sympathoadrenal system at rest and after exercise.

The Hemolymph of the ascidian Styela plicata (Chordata-Tunicata) contains heparin inside basophil-like cells and a unique sulfated galactoglucan in the plasma.

PubMed

de Barros, Cintia M; Andrade, Leonardo R; Allodi, Silvana; Viskov, Christian; Mourier, Pierre A; Cavalcante, Moisés C M; Straus, Anita H; Takahashi, Helio K; Pomin, Vitor H; Carvalho, Vinicius F; Martins, Marco A; Pavão, Mauro S G

2007-01-19

The hemolymph of ascidians (Chordata-Tunicata) contains different types of hemocytes embedded in a liquid plasma. In the present study, heparin and a sulfated heteropolysaccharide were purified from the hemolymph of the ascidian Styela plicata. The heteropolysaccharide occurs free in the plasma, is composed of glucose ( approximately 60%) and galactose ( approximately 40%), and is highly sulfated. Heparin, on the other hand, occurs in the hemocytes, and high performance liquid chromatography of the products formed by degradation with specific lyases revealed that it is composed mainly by the disaccharides DeltaUA(2SO(4))-1-->4-beta-d-GlcN(SO(4)) (39.7%) and DeltaUA(2SO(4))-1-->4-beta-d-GlcN(SO(4))(6SO(4)) (38.2%). Small amounts of the 3-O-sulfated disaccharides DeltaUA(2SO(4))-1-->4-beta-d-GlcN(SO(4))(3SO(4)) (9.8%) and DeltaUA(2SO(4))-1-->4-beta-d-GlcN(SO(4))(3SO(4))(6SO(4)) (3.8%) were also detected. These 3-O-sulfated disaccharides were demonstrated to be essential for the binding of the hemocyte heparin to antithrombin III. Electron microscopy techniques were used to characterize the ultrastructure of the hemocytes and to localize heparin and histamine in these cells. At least five cell types were recognized and classified as univacuolated and multivacuolated cells, amebocytes, hemoblasts, and granulocytes. Immunocytochemistry showed that heparin and histamine co-localize in intracellular granules of only one type of hemocyte, the granulocyte. These results show for the first time that in ascidians, a sulfated galactoglucan circulates free in the plasma, and heparin occurs as an intracellular product of a circulating basophil-like cell.

Impact of adopting a vegan diet or an olestra supplementation on plasma organochlorine concentrations: results from two pilot studies.

PubMed

Arguin, Hélène; Sánchez, Marina; Bray, George A; Lovejoy, Jennifer C; Peters, John C; Jandacek, Ronald J; Chaput, Jean-Philippe; Tremblay, Angelo

2010-05-01

The aim of these studies was to evaluate the potential of some nutritional approaches to prevent or reduce the body load of organochlorines (OC) in humans. Study 1 compared plasma OC concentrations between vegans and omnivores while study 2 verified if the dietary fat substitute olestra could prevent the increase in OC concentrations that is generally observed in response to a weight-reducing programme. In study 1, nine vegans and fifteen omnivores were recruited and the concentrations of twenty-six OC (beta-hexachlorocyclohexane (beta-HCH), p, p'-dichlorodiphenyldichloroethane (p, p'-DDE), p, p'-dichlorodiphenyltrichloroethane (p, p'-DDT), hexachlorobenzene, mirex, aldrin, alpha-chlordane, gamma-chlordane, oxychlordane, cis-nonachlor, trans-nonachlor, polychlorinated biphenyl (PCB) nos. 28, 52, 99, 101, 105, 118, 128, 138, 153, 156, 170, 180, 183 and 187, and aroclor 1260) were determined. In study 2, the concentrations of these twenty-six OC were measured before and after weight loss over 3 months in thirty-seven obese men assigned to one of the following treatments: standard group (33 % fat diet; n 13), fat-reduced group (25 % fat diet; n 14) or fat-substituted group (1/3 of dietary lipids substituted by olestra; n 10). In study 1, plasma concentrations of five OC compounds (aroclor 1260 and PCB 99, PCB 138, PCB 153 and PCB 180) were significantly lower in vegans compared with omnivores. In study 2, beta-HCH was the only OC which decreased in the fat-substituted group while increasing in the other two groups (P = 0.045). In conclusion, there was a trend toward lesser contamination in vegans than in omnivores, and olestra had a favourable influence on beta-HCH but did not prevent plasma hyperconcentration of the other OC during ongoing weight loss.

Plasma progesterone levels and luteal activity during gestation and prolonged oviductal egg retention in a tropical lizard, Calotes versicolor.

PubMed

Shanbhag, B A; Radder, R S; Saidapur, S K

2001-07-01

Plasma progesterone (P) levels and luteal and adrenal activities were studied during normal gestation and unusual prolonged period of oviductal egg retention in a polyautochronic, multiclutched lizard, Calotes versicolor. The normal gestation period (approximately 15 days) was categorized into four stages: stage I--a few hours following ovulation, stage II--eggs with shell and embryo at primitive streak, stage III--embryonic stages 16-20, and stage IV--prior to ovipostion (stages 26-27). The gravid lizards maintained in captivity retained eggs in their oviducts for 45 days. Plasma P levels were low in stage I, increased significantly during stage II, declined in stage III, and reached their lowest in stage IV of gestation. 3Beta-hydroxysteroid dehydrogenase (3beta-HSDH) activity was greater in lutein cells at stage II and was present in traces in stage IV gestation. Interestingly, plasma P titers that were high in lizards with eggs retained longer though the corpora lutea (CL) showed a trace 3beta-HSDH activity. However, 3beta-HSDH activity was greater in the adrenocortical cells in these lizards than that in lizards during a normal gestation period. The present study on C. versicolor shows that the CL remains active and secretes P only during the early part of the gestation. The drop in P level during the later part of gestation might facilitate growth of a second set of vitellogenic follicles. During unfavorable conditions when the lizards are forced to retain eggs in the oviduct, the adrenal glands seem to secrete progesterone to help in egg retention and in inhibition of oviposition.

Electroencephalographic response following midazolam-induced general anesthesia: relationship to plasma and effect-site midazolam concentrations.

PubMed

Miyake, Wakako; Oda, Yutaka; Ikeda, Yuko; Hagihira, Satoshi; Iwaki, Hiroyoshi; Asada, Akira

2010-06-01

To examine the relationships between effect-site concentrations and electroencephalographic parameters after the induction of general anesthesia with midazolam. Twenty-four patients with American Society of Anesthesiologists status I or II were randomly allocated to receive either an intravenous (i.v.) bolus of midazolam 0.2 mg kg(-1) (small-dose group, n = 12) or 0.3 mg kg(-1) (large-dose group, n = 12) for induction of general anesthesia in a double-blind experimental design. The bispectral index (BIS), 95% spectral edge frequency (SEF95), spectral power density, and plasma concentrations of midazolam were measured for 60 min following the induction of general anesthesia. Plasma and simulated effect-site concentrations of midazolam were significantly higher in the large-dose group than in the small-dose group (P = 0.005 and <0.001, respectively). There was a correlation between the relative beta ratio and BIS (r (2) = 0.30, P < 0.001; n = 168); however, effect-site concentrations of midazolam showed no association with BIS, relative beta ratio, or SEF95 (r (2) = 0.07, 0.11 and 0.01, respectively; n = 168). The electroencephalographic spectral power density in the beta-band (>/=13 and <30 Hz) was significantly increased after induction and was significantly larger in the large-dose group than in the small-dose group (P = 0.009). Following the induction of general anesthesia with i.v. midazolam 0.2 or 0.3 mg kg(-1), the BIS was positively correlated with the relative beta ratio. Despite a rapid decrease in the plasma and effect-site concentrations of midazolam, the average BIS remained >60 for 60 min after induction, reflecting an increased power of the electroencephalographic high-frequency band.

Novel plasma source for safe beryllium spectral line studies in the presence of beryllium dust

NASA Astrophysics Data System (ADS)

Stankov, B. D.; Vinić, M.; Gavrilović Božović, M. R.; Ivković, M.

2018-05-01

Plasma source for beryllium spectral line studies in the presence of beryllium dust particles was realised. The guideline during construction was to prevent exposure to formed dust, considering the toxicity of beryllium. Plasma source characterization through determination of optimal working conditions is described. The necessary conditions for Be spectral line appearance and optimal conditions for line shape measurements are found. It is proven experimentally that under these conditions dust appears coincidently with the second current maximum. The electron density measured after discharge current maximum is determined from the peak separation of the hydrogen Balmer beta spectral line, and the electron temperature is determined from the ratios of the relative intensities of Be spectral lines emitted from successive ionized stages of atoms. Maximum values of electron density and temperature are measured to be 9.3 × 1022 m-3 and 16 800 K, respectively. Construction details and testing of the BeO discharge tube in comparison with SiO2 and Al2O3 discharge tubes are also presented in this paper.

Noninductively Driven Tokamak Plasmas at Near-Unity Toroidal Beta

DOE PAGES

Schlossberg, David J.; Bodner, Grant M.; Bongard, Michael W.; ...

2017-07-01

Access to and characterization of sustained, toroidally confined plasmas with a very high plasma-to-magnetic pressure ratio (β t), low internal inductance, high elongation, and nonsolenoidal current drive is a central goal of present tokamak plasma research. Stable access to this desirable parameter space is demonstrated in plasmas with ultralow aspect ratio and high elongation. Local helicity injection provides nonsolenoidal sustainment, low internal inductance, and ion heating. Equilibrium analyses indicate β t up to ~100% with a minimum |B| well spanning up to ~50% of the plasma volume.

Destruction of {alpha}-synuclein based amyloid fibrils by a low temperature plasma jet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karakas, Erdinc; Laroussi, Mounir; Munyanyi, Agatha

2010-10-04

Amyloid fibrils are ordered beta-sheet aggregates that are associated with a number of neurodegenerative diseases such as Alzheimer and Parkinson. At present, there is no cure for these progressive and debilitating diseases. Here we report initial studies that indicate that low temperature atmospheric pressure plasma can break amyloid fibrils into smaller units in vitro. The plasma was generated by the 'plasma pencil', a device capable of emitting a long, low temperature plasma plume/jet. This avenue of research may facilitate the development of a plasma-based medical treatment.

Noninductively Driven Tokamak Plasmas at Near-Unity Toroidal Beta.

PubMed

Schlossberg, D J; Bodner, G M; Bongard, M W; Burke, M G; Fonck, R J; Perry, J M; Reusch, J A

2017-07-21

Access to and characterization of sustained, toroidally confined plasmas with a very high plasma-to-magnetic pressure ratio (β_{t}), low internal inductance, high elongation, and nonsolenoidal current drive is a central goal of present tokamak plasma research. Stable access to this desirable parameter space is demonstrated in plasmas with ultralow aspect ratio and high elongation. Local helicity injection provides nonsolenoidal sustainment, low internal inductance, and ion heating. Equilibrium analyses indicate β_{t} up to ∼100% with a minimum |B| well spanning up to ∼50% of the plasma volume.

BETA (Bitter Electromagnet Testing Apparatus) Design and Testing

NASA Astrophysics Data System (ADS)

Bates, Evan; Birmingham, William; Rivera, William; Romero-Talamas, Carlos

2016-10-01

BETA is a 1T water cooled Bitter-type magnetic system that has been designed and constructed at the Dusty Plasma Laboratory of the University of Maryland, Baltimore County to serve as a prototype of a scaled 10T version. Currently the system is undergoing magnetic, thermal and mechanical testing to ensure safe operating conditions and to prove analytical design optimizations. These magnets will function as experimental tools for future dusty plasma based and collaborative experiments. An overview of design methods used for building a custom made Bitter magnet with user defined experimental constraints is reviewed. The three main design methods consist of minimizing the following: ohmic power, peak conductor temperatures, and stresses induced by Lorentz forces. We will also discuss the design of BETA which includes: the magnet core, pressure vessel, cooling system, power storage bank, high powered switching system, diagnostics with safety cutoff feedback, and data acquisition (DAQ)/magnet control Matlab code. Furthermore, we present experimental data from diagnostics for validation of our analytical preliminary design methodologies and finite element analysis calculations. BETA will contribute to the knowledge necessary to finalize the 10 T magnet design.

Effect of salt acclimatization on 3 beta-hydroxysteroid dehydrogenase/isomerase activity in the interrenal of Bufo arenarum.

PubMed

Pozzi, Andrea G; Lantos, Carlos P; Ceballos, Nora R

2002-03-01

In amphibians, aldosterone (Aldo) is particularly important in the regulation of Na(+) exchange by skin and urinary bladder. In previous works we studied a key enzyme in Aldo biosynthesis, the 3 beta-hydroxysteroid dehydrogenase/isomerase (3 beta HSD/I), in the interrenals of Bufo arenarum. In those works a dual localization of the 3 beta HSD/I in both microsomes and mitochondria was described. The mitochondrial, but not the microsomal, enzyme prefers the immediate Aldo precursor, 3 beta-analogue of aldosterone, as substrate. In this order, the enzyme 3 beta HSD/I would be not only a key enzyme for the synthesis of Aldo but additionally, due to its microsomal and mitochondrial localization, a possible target for the regulation of Aldo biosynthesis. With this rationale in mind, we have used in vivo and in vitro approaches to study Aldo regulation. In the present investigation the levels of Aldo were determined in plasma of winter (W) and summer (S) toads subjected to different saline concentrations (0.125 and 0.15 M) or kept on wet land. Saline hyperosmotically treated toads had significantly lower levels than isoosmotically treated toads. These results are consistent with the response in mammals, in which salt loading provokes a reduction in Aldo secretion. In W toads, plasmatic corticosterone (B) concentration was higher than Aldo concentration, whereas in S toads, B/Aldo ratio approached unity. The reduction of Aldo levels after saline dehydration was due to a decline in its biosynthesis. K(m) and V(max) values for 3 beta HSD/I were calculated for mitochondrial and microsomal fractions obtained from animals acclimated to 0.15 M NaCl or kept on land. As previously described, V(max) differs between W and S toads. However, only mitochondrial V(max) changed as a consequence of saline adaptation, suggesting that the mitochondrial enzyme could be involved in the regulation of Aldo biosynthesis.

Light Weight Portable Plasma Medical Device - Plasma Engineering Research Laboratory

DTIC Science & Technology

2011-10-01

Millennial Student. 15. Thiyagarajan, M. (2011). Portable Plasma Biomedical Device for Cancer Treatment. Irvine, California: ASME Emerging...American Society of Mechanical Engineers Sigma Xi Toastmasters International Club MIT Entrepreneur Club Eta Kappa Nu Tau Beta Pi Institute of...Learning Environment. Corpus Christi, TX: TAMUCC 1st Faculty Symposium: Course Design for the Millennial Student. Thiyagarajan, M. (2011). Portable

Development of a low-energy and high-current pulsed neutral beam injector with a washer-gun plasma source for high-beta plasma experiments.

PubMed

Ii, Toru; Gi, Keii; Umezawa, Toshiyuki; Asai, Tomohiko; Inomoto, Michiaki; Ono, Yasushi

2012-08-01

We have developed a novel and economical neutral-beam injection system by employing a washer-gun plasma source. It provides a low-cost and maintenance-free ion beam, thus eliminating the need for the filaments and water-cooling systems employed conventionally. In our primary experiments, the washer gun produced a source plasma with an electron temperature of approximately 5 eV and an electron density of 5 × 10(17) m(-3), i.e., conditions suitable for ion-beam extraction. The dependence of the extracted beam current on the acceleration voltage is consistent with space-charge current limitation, because the observed current density is almost proportional to the 3/2 power of the acceleration voltage below approximately 8 kV. By optimizing plasma formation, we successfully achieved beam extraction of up to 40 A at 15 kV and a pulse length in excess of 0.25 ms. Its low-voltage and high-current pulsed-beam properties enable us to apply this high-power neutral beam injection into a high-beta compact torus plasma characterized by a low magnetic field.

Phenomenology of beam driven modes in the field reversed configuration

NASA Astrophysics Data System (ADS)

Magee, Richard; Bolte, Nathan; Clary, Ryan; Necas, Ales; Korepanov, Sergey; Smirnov, Artem; Thompson, Matthew; Tajima, Toshiki; THE TAE Team

2016-10-01

The C-2U experiment offers a unique plasma environment combining a high beta field reversed configuration (FRC) embedded in a low beta magnetic mirror with high power neutral beam injection. The beams are injected tangentially into a modest magnetic field so that the orbits of the resulting fast ions encircle the entire plasma. These large orbit particles sustain and stabilize the plasma and suppress turbulence. Measurements of magnetic fluctuations at the edge of the plasma reveal the presence of three coherent beam driven modes: a low frequency, chirping mode, a mode near the ion cyclotron frequency, and a high frequency compressional Alfven mode. Remarkably, none of these modes are observed to have a deleterious effect on global plasma confinement. In fact, the cyclotron mode has the beneficial effect of dramatically enhancing the DD fusion reaction rate by drawing a trail from the plasma ion energy distribution on a sub-collisional timescale. In this presentation, we experimentally characterize the beam driven modes in the C-2U FRC with data from multiple diagnostics including magnetics, spectroscopy, neutral particle analyzers and fusion product diagnostics. Results are compared to a particle-in-cell simulation in a simplified geometry.

Effects of estrogenic (o,p'-DDT; octylphenol) and anti-androgenic (p,p'-DDE) chemicals on indicators of endocrine status in juvenile male summer flounder (Paralichthys dentatus).

PubMed

Mills, L J; Gutjahr-Gobell, R E; Haebler, R A; Horowitz, D J; Jayaraman, S; Pruell, R J; McKinney, R A; Gardner, G R; Zaroogian, G E

2001-04-01

Laboratory experiments were conducted with male summer flounder to assess the value of selected measures of endocrine status in fish as indicators of exposure to endocrine-disrupting contaminants. Effects of 1,1,1-trichloro-2-(p-chlorophenyl)-2-(o-chlorophenyl) ethane (o,p'-DDT), octylphenol and 1,1-dichloro-2,2-bis (p-chlorophenyl) ethylene (p,p'-DDE) on hepatosomatic and gonadosomatic indices, plasma steroid hormone levels, vitellogenin production, and gonadal development were evaluated in laboratory-raised, juvenile male summer flounder. Flounder were injected twice with test chemical in a coconut oil carrier. Each chemical was tested at three different concentrations. Estrogenic (o,p'-DDT; octylphenol) and anti-androgenic (p,p'-DDE) chemicals were evaluated alone and in combination (octylphenol plus o,p'-DDT or p,p'-DDE). Additionally, some fish were treated with the natural ligand for the estrogen receptor, 17beta-estradiol. Blood and tissues from different fish in each treatment were sampled 4, 6 and 8 weeks after the first injection. Fish exposed to a combination of o,p'-DDT plus octylphenol were also sampled after 15 weeks. In all cases, responses of fish exposed to a test chemical were compared to control fish sampled at the same time. The following significant differences, relative to controls, were observed in at least one sampling time or at least one concentration of chemical. 17beta-Estradiol-treated flounder exhibited decreased gonadosomatic index (GSI), altered hepatosomatic index (HSI), elevated plasma estradiol, reduced plasma testosterone, and high levels of plasma vitellogenin. Fish treated with o,p'-DDT showed lower GSI, no change in HSI or plasma estradiol, depression of plasma testosterone, and induction of vitellogenesis. Octylphenol treatment resulted in lower GSI, no change in HSI, initially increased plasma estradiol and decreased testosterone, and no vitellogenin production. p,p'-DDE treatment did not significantly alter any indicator relative to controls. In experiments using combinations of chemicals, flounder receiving o,p'-DDT plus octylphenol had lower GSI after 8 weeks and elevated plasma estradiol after 15 weeks exposure. Fish treated with p,p'-DDE plus octylphenol for 8 weeks exhibited a significantly lower GSI. Overall, lower GSI and plasma testosterone levels, relative to controls, were consistent indicators of exposure to estrogenic chemicals in juvenile male flounder. No indicators were found that would identify exposure to the mammalian anti-androgen p,p'-DDE.

Optimizing the effect of plant sterols on cholesterol absorption in man.

PubMed

Mattson, F H; Grundy, S M; Crouse, J R

1982-04-01

During three experimental periods, nine adults were hospitalized on a metabolic ward and fed a meal containing 500 mg of cholesterol as a component of scrambled eggs. In addition, the meal contained: 1) no additive, 2) 1 g beta-sitosterol, or 3) 2 g beta-sitosteryl oleate. Stools for the succeeding 5 days were analyzed to determine the percentage of the cholesterol in the test meal that was absorbed. The addition of beta-sitosterol resulted in a 42% decrease in cholesterol absorption; the beta-sitosteryl oleate caused a 33% reduction. These results indicate that the judicious addition of beta-sitosterol or beta-sitosteryl oleate to meals containing cholesterol-rich foods will result in a significant decrease in cholesterol absorption, with a consequent decrease in plasma cholesterol.

Increased confinement and beta by inductive poloidal current drive in the RFP

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sarff, J.S.; Lanier, N.E.; Prager, S.C.

1996-10-01

Progress in understanding magnetic-fluctuation-induced transport in the reversed field pinch (RFP) has led to the idea of current profile control to reduce fluctuations and transport. With the addition of inductive poloidal current drive in the Madison Symmetric Torus (MST), the magnetic fluctuation amplitude is halved, leading to a four- to five-fold increase in the energy confinement time to {tau}{sub E}{approximately}5 ms as a result of both decreased plasma resistance and increased stored thermal energy. The record low fluctuation amplitude coincides with a record high electron temperature of {approximately}600 eV (for MST), and beta {beta} = 2{mu}{sub 0} / B(a){sup 2}more » increases from 6% to 8% compared with conventional MST RFP plasmas. Other improvements include increased particle confinement and impurity reduction. 19 refs., 4 figs., 1 tab.« less

beta. -lipotropin is the major opioid-like peptide of human pituitary and rat pars distalis: lack of significant. beta. -endorphin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liotta, A.S.; Suda, T.; Krieger, D.T.

1978-06-01

..beta..-Lipotropin is the predominant opioid peptide of the human pituitary and rat pars distalis and is present in concentrations essentially equimolar with corticotropin. When freshly obtained nonfrozen rat anterior pituitaries were homogenized with 0.2 M HCl, approximately 98% of the immunoreactivity detected utilizing an antiserum that crossreacts equally with ..beta..-lipotropin and ..beta..-endorphin coeluted with /sup 125/I-labeled human ..beta..-lipotropin upon molecular sieve chromatography. The remainder of the activity eluted with synthetic human ..beta..-endorphin. Similar results were obtained for human pituitary. HCl homogenization of thawed tissue or homogenization of fresh tissue with acetic acid yielded substantially greater concentrations of ..beta..-endorphin and decreasedmore » concentrations of ..beta..-lipotropin. In human subjects, acute anterior pituitary stimulation using either insulin-induced hypoglycemia or vasopressin administration was associated with increased plasma ..beta..-lipotropin and corticotropin levels. At the time of peak concentrations, no significant levels of ..beta..-endorphin were detectable. These data indicate the lack of significant amounts of ..beta..-endorphin in human pituitary. Additionally, there appears to be no specific intrapituitary conversion of ..beta..-lipotropin to ..beta..-endorphin.« less

Measurement of the alpha4beta2* nicotinic acetylcholine receptor ligand 2-[(18)F]Fluoro-A-85380 and its metabolites in human blood during PET investigation: a methodological study.

PubMed

Sorger, Dietlind; Becker, Georg A; Patt, Marianne; Schildan, Andreas; Grossmann, Udo; Schliebs, Reinhard; Seese, Anita; Kendziorra, Kai; Kluge, Magnus; Brust, Peter; Mukhin, Alexey G; Sabri, Osama

2007-04-01

2-[(18)F]fluoro-A-85380 (2-[(18)F]FA) is a new radioligand for noninvasive imaging of alpha4beta2* nicotinic acetylcholine receptors (nAChRs) by positron emission tomography (PET) in human brain. In most cases, quantification of 2-[(18)F]FA receptor binding involves measurement of free nonmetabolized radioligand concentration in blood. This requires an efficient and reliable method to separate radioactive metabolites from the parent compound. In the present study, three analytical methods, thin layer chromatography (TLC), high-performance liquid chromatography (HPLC) and solid phase extraction (SPE) have been tested. Reversed-phase TLC of deproteinized aqueous samples of plasma provides good estimates of 2-[(18)F]FA and its metabolites. However, because of the decreased radioactivity in plasma samples, this method can be used in humans over the first 2 h after radioligand injection only. Reliable quantification of the parent radioligand and its main metabolites was obtained using reversed-phase HPLC, followed by counting of eluted fractions in a well gamma counter. Three main and five minor metabolites of 2-[(18)F]FA were detected in human blood using this method. On average, the unchanged 2-[(18)F]FA fraction in plasma of healthy volunteers measured at 14, 60, 120, 240 and 420 min after radioligand injection was 87.3+/-2.2%, 74.4+/-3%, 68.8+/-5%, 62.3+/-8% and 61.0+/-8%, respectively. In patients with neurodegenerative disorders, the values corresponding to the three last time points were significantly lower. The fraction of nonmetabolized 2-[(18)F]FA in plasma determined using SPE did not differ significantly from that obtained by HPLC (+gamma counting) (n=73, r=.95). Since SPE is less time-consuming than HPLC and provides comparable results, we conclude that SPE appears to be the most suitable method for measurement of 2-[(18)F]FA parent fraction during PET investigations.

Circulating DNA: a potential marker of sickle cell crisis.

PubMed

Vasavda, Nisha; Ulug, Pinar; Kondaveeti, Sheila; Ramasamy, Karthik; Sugai, Taku; Cheung, Gordon; Rees, David C; Awogbade, Moji; Bannister, Sybil; Cunningham, Juliette; Menzel, Stephan; Thein, Swee Lay

2007-10-01

Free circulating DNA is present in the plasma of healthy subjects, and is elevated in conditions characterized by increased cell death, such as cancer and physical trauma. Analysis of circulating DNA in plasma could provide a useful biomarker in sickle cell disease (SCD) in view of the increased cell turnover through chronic ongoing haemolysis, recurrent vaso-occlusion and inflammation. Plasma DNA was determined by real-time quantitative polymerase chain reaction (PCR) amplification of the beta-globin gene (HBB) in 154 patients with SCD [105 haemoglobin (Hb)SS, 46 HbSC and three HbS/beta(0) thalassaemia] and 53 ethnically matched controls. Blood samples were obtained from all patients in steady state; 21 of the 154 patients were also sampled during admission to hospital for acute pain. Median concentration of circulating plasma DNA in acute pain was more than 10-fold that in steady state and in controls - 10070 vs. 841 and 10070 vs. 933 genome equivalents/ml respectively (P < 0.0001, in both cases). During steady state, patients had plasma DNA levels similar to controls. Plasma DNA levels in SCD correlated with C-reactive protein levels (P < 0.005) and total white cell counts (P < 0.05) in steady state. The study shows that plasma DNA concentration may have potential as a biomarker in sickle cell patients.

Pregnancy Specific Glycoprotein 23 binds to CD151 and Induces the Secretion of IL-10 and TGF-beta1 in Murine Macrophages

DTIC Science & Technology

2007-07-11

levels of trophoblast-specific beta-1-globulin (SP1) and alpha -1- fetoprotein (AFP) in pregnant women with rheumatoid arthritis]. Cesk Gynekol, 1991...transforming growth factor-beta TNF-": tumor necrosis factor- alpha TXA: thromboxane A2 uNK: uterine natural killer cell 1 PART ONE...specific glycoprotein, pregnancy-associated plasma protein A, "- fetoprotein , as well as an array of cytokines, including IL-6, and TGF-! [95

Plasma plasminogen activator inhibitor-1 levels and nonalcoholic fatty liver in individuals with features of metabolic syndrome.

PubMed

de Larrañaga, Gabriela; Wingeyer, Silvia Perés; Graffigna, Mabel; Belli, Susana; Bendezú, Karla; Alvarez, Silvia; Levalle, Oscar; Fainboim, Hugo

2008-07-01

Fatty liver represents the liver component of metabolic syndrome and may be involved in plasminogen activator inhibitor-1 (PAI-1) synthesis. We studied plasma PAI-1 levels and relationships with risk factors for metabolic syndrome, including fatty liver, in 170 patients. Liver ultrasound scan was performed on all patients, and a liver biopsy was performed on those patients with chronically elevated transaminase levels. Plasma PAI-1 levels correlated significantly (P < .05) with body mass index, degree of steatosis, insulin resistance, insulin level, waist circumference, triglycerides, and high-density lipoprotein (HDL) -cholesterol. However, only body mass index (beta = .455) and HDL-cholesterol (beta = .293) remained predictors of PAI-1 levels. Liver biopsy revealed a significant correlation (P < .05) between insulin resistance (r = 0.381) or insulin level (r = 0.519) and liver fibrosis. In patients presenting features of metabolic syndrome, plasma PAI-1 levels were mainly conditioned by the whole-body fat content.

Counterstreaming beams and flat-top electron distributions observed with Langmuir, Whistler, and compressional Alfvén waves in earth's magnetic tail.

PubMed

Teste, Alexandra; Parks, George K

2009-02-20

Relevant new clues to wave-particle interactions have been obtained in Earth's plasma sheet (PS). The plasma measurements made on Cluster spacecraft show that broadband (approximately 2-6 kHz) electrostatic emissions, in the PS boundary layer, are associated with cold counterstreaming electrons flowing at 5-12x10(3) km s(-1) through hot Maxwellian plasma. In the current sheet (CS), electromagnetic whistler mode waves (approximately 10-80 Hz) and compressional Alfvén waves (<2 Hz) are detected with flat-topped electron distributions whose cutoff speeds are approximately 15-17x10(3) km s(-1). These waves are damped in the central CS where |B|

Quantitative Impact of Plasma Clearance and Down-regulation on GLP-1 Receptor Molecular Imaging.

PubMed

Zhang, Liang; Thurber, Greg M

2016-02-01

Quantitative molecular imaging of beta cell mass (BCM) would enable early detection and treatment monitoring of type 1 diabetes. The glucagon-like peptide-1 (GLP-1) receptor is an attractive target due to its beta cell specificity and cell surface location. We quantitatively investigated the impact of plasma clearance and receptor internalization on targeting efficiency in healthy B6 mice. Four exenatide-based probes were synthesized that varied in molecular weight, binding affinity, and plasma clearance. The GLP-1 receptor internalization rate and in vivo receptor expression were quantified. Receptor internalization (54,000 receptors/cell in vivo) decreased significantly within minutes, reducing the benefit of a slower-clearing agent. The multimers and albumin binding probes had higher kidney and liver uptake, respectively. Slow plasma clearance is beneficial for GLP-1 receptor peptide therapeutics. However, for exendin-based imaging of islets, down-regulation of the GLP-1 receptor and non-specific background uptake result in a higher target-to-background ratio for fast-clearing agents.

Quantitative Impact of Plasma Clearance and Down-regulation on GLP-1 Receptor Molecular Imaging

PubMed Central

Zhang, Liang; Thurber, Greg M.

2016-01-01

Purpose Quantitative molecular imaging of beta cell mass (BCM) would enable early detection and treatment monitoring of type-1 diabetes. The glucagon like peptide-1 (GLP-1) receptor is an attractive target due to its beta cell specificity and cell surface location. We quantitatively investigated the impact of plasma clearance and receptor internalization on targeting efficiency in healthy B6 mice. Procedures Four exenatide-based probes were synthesized that varied in molecular weight, binding affinity, and plasma clearance. The GLP-1 receptor internalization rate and in vivo receptor expression were quantified. Results Receptor internalization (54,000 receptors/cell in vivo) decreased significantly within minutes, reducing the benefit of a slower clearing agent. The multimers and albumin binding probes had higher kidney and liver uptake, respectively. Conclusions Slow plasma clearance is beneficial for GLP-1 receptor peptide therapeutics. However, for exendin-based imaging of islets, downregulation of the GLP-1 receptor and non-specific background uptake result in a higher TBR for fast-clearing agents. PMID:26194012

AE activity during transient beta drops in high poloidal beta discharges

NASA Astrophysics Data System (ADS)

Huang, J.; Gong, X. Z.; Ren, Q. L.; Ding, S. Y.; Qian, J. P.; Pan, C. K.; Li, G. Q.; Heidbrink, W. W.; Garofalo, A. M.; McClenaghan, J.

2016-10-01

Enhanced AE activity has been observed during transient beta drops in high poloidal beta DIII-D discharges with internal transport barriers (ITBs). These drops in beta are believed to be caused by n=1 external kink modes. In some discharges, beta recovers within 200 ms but, in others, beta stays suppressed. A typical discharge has βP 3, qmin 3, and q95 12. The drop in beta affects both fast ions and thermal particles, and a drop is also observed in the density and rotation. The enhanced AE activity follows the instability that causes the beta drop, is largest at the lowest beta, and subsides as beta recovers. MHD stability analysis is planned. A database study of the plasma conditions associated with the collapse will be also presented. Supported in part by the US Department of Energy under DE-FC02-04ER54698, DE-AC05-06OR23100, and by the National Natural Science Foundation of China 11575249, and the National Magnetic Confinement Fusion Program of China No. 2015GB110005.

Segregation of two spectrin isoforms: polarized membrane-binding sites direct polarized membrane skeleton assembly.

PubMed

Dubreuil, R R; Maddux, P B; Grushko, T A; MacVicar, G R

1997-10-01

Spectrin isoforms are often segregated within specialized plasma membrane subdomains where they are thought to contribute to the development of cell surface polarity. It was previously shown that ankyrin and beta spectrin are recruited to sites of cell-cell contact in Drosophila S2 cells expressing the homophilic adhesion molecule neuroglian. Here, we show that neuroglian has no apparent effect on a second spectrin isoform (alpha beta H), which is constitutively associated with the plasma membrane in S2 cells. Another membrane marker, the Na,K-ATPase, codistributes with ankyrin and alpha beta spectrin at sites of neuroglian-mediated contact. The distributions of these markers in epithelial cells in vivo are consistent with the order of events observed in S2 cells. Neuroglian, ankyrin, alpha beta spectrin, and the Na,K-ATPase colocalize at the lateral domain of salivary gland cells. In contrast, alpha beta H spectrin is sorted to the apical domain of salivary gland and somatic follicle cells. Thus, the two spectrin isoforms respond independently to positional cues at the cell surface: in one case an apically sorted receptor and in the other case a locally activated cell-cell adhesion molecule. The results support a model in which the membrane skeleton behaves as a transducer of positional information within cells.

Carnitine Palmitoyltransferase 1B 531K Allele Carriers Sustain a Higher Respiratory Quotient after Aerobic Exercise, but β3-Adrenoceptor 64R Allele Does Not Affect Lipolysis: A Human Model

PubMed Central

Gómez-Gómez, Eduardo; Ríos-Martínez, Martín Efrén; Castro-Rodríguez, Elena Margarita; Del-Toro-Equíhua, Mario; Ramírez-Flores, Mario; Delgado-Enciso, Ivan; Pérez-Huitimea, Ana Lilia; Baltazar-Rodríguez, Luz Margarita; Velasco-Pineda, Gilberto; Muñiz-Murguía, Jesús

2014-01-01

Carnitine palmitoyltransferase IB (CPT1B) and adrenoceptor beta-3 (ADRB3) are critical regulators of fat metabolism. CPT1B transports free acyl groups into mitochondria for oxidation, and ADRB3 triggers lipolysis in adipocytes, and their respective polymorphisms E531K and W64R have been identified as indicators of obesity in population studies. It is therefore important to understand the effects of these mutations on ADRB3 and CPT1B function in adipose and skeletal muscle tissue, respectively. This study aimed to analyze the rate of lipolysis of plasma indicators (glycerol, free fatty acids, and beta hydroxybutyrate) and fat oxidation (through the non-protein respiratory quotient). These parameters were measured in 37 participants during 30 min of aerobic exercise at approximately 62% of maximal oxygen uptake, followed by 30 min of recovery. During recovery, mean respiratory quotient values were higher in K allele carriers than in non-carriers, indicating low post-exercise fatty acid oxidation rates. No significant differences in lipolysis or lipid oxidation were observed between R and W allele carriers of ADRB3 at any time during the aerobic load. The substitution of glutamic acid at position 531 by lysine in the CPT1B protein decreases the mitochondrial beta-oxidation pathway, which increases the non-protein respiratory quotient value during recovery from exercise. This may contribute to weight gain or reduced weight-loss following exercise. PMID:24905907

The Statistical Properties of Solar Wind Temperature Parameters Near 1 au

NASA Astrophysics Data System (ADS)

Wilson, Lynn B., III; Stevens, Michael L.; Kasper, Justin C.; Klein, Kristopher G.; Maruca, Bennett A.; Bale, Stuart D.; Bowen, Trevor A.; Pulupa, Marc P.; Salem, Chadi S.

2018-06-01

We present a long-duration (∼10 yr) statistical analysis of the temperatures, plasma betas, and temperature ratios for the electron, proton, and alpha-particle populations observed by the Wind spacecraft near 1 au. The mean(median) scalar temperatures are T e,tot = 12.2(11.9) eV, T p,tot = 12.7(8.6) eV, and T α,tot = 23.9(10.8) eV. The mean(median) total plasma betas are β e,tot = 2.31(1.09), β p,tot = 1.79(1.05), and β α,tot = 0.17(0.05). The mean(median) temperature ratios are (T e /T p )tot = 1.64(1.27), (T e /T α )tot = 1.24(0.82), and (T α /T p )tot = 2.50(1.94). We also examined these parameters during time intervals that exclude interplanetary (IP) shocks, times within the magnetic obstacles (MOs) of interplanetary coronal mass ejections (ICMEs), and times that exclude MOs. The only times that show significant alterations to any of the parameters examined are those during MOs. In fact, the only parameter that does not show a significant change during MOs is the electron temperature. Although each parameter shows a broad range of values, the vast majority are near the median. We also compute particle–particle collision rates and compare to effective wave–particle collision rates. We find that, for reasonable assumptions of wave amplitude and occurrence rates, the effect of wave–particle interactions on the plasma is equal to or greater than the effect of Coulomb collisions. Thus, wave–particle interactions should not be neglected when modeling the solar wind.

Correlation of nitric oxide and other free radicals with the severity of acute pancreatitis and complicated systemic inflammatory response syndrome.

PubMed

Que, Ri-sheng; Cao, Li-ping; Ding, Guo-ping; Hu, Jun-an; Mao, Ke-jie; Wang, Gui-feng

2010-05-01

To investigate the correlation of nitric oxide (NO) and other free radicals with the severity of acute pancreatitis (AP) and complicated systemic inflammatory response syndrome (SIRS). Fifty AP patients (24 simple AP patients and 26 patients with AP complicated by SIRS) were involved in the study. Fifty healthy volunteers were included as controls. Acute Physiology and Chronic Health Evaluation II (APACHE II) scores were evaluated, and plasma NO, plasma lipid peroxides, plasma vitamin E, plasma beta-carotene, whole-blood glutathione (GSH), and the activity of plasma GSH peroxidase were measured. Compared with the control group, the APACHE II scores heightened in the AP group, and the SIRS group had the highest APACHE II scores (P < 0.005, P < 0.001, respectively). Plasma NO and plasma lipid peroxides increased with the heightening APACHE II scores, demonstrating a significant linear positive correlation (r = 0.618, r = 0.577, respectively; P < 0.001). Plasma vitamin E, plasma beta-carotene, whole-blood GSH, and the activity of plasma GSH peroxidase decreased with the heightening APACHE II scores, demonstrating a significant linear negative correlation (r = -0.600, r = -0.609, r = -0.559, r = -0.592, respectively; P < 0.001). Nitric oxide and other free radicals take part in the aggravation of oxidative stress and oxidative injury and may play important roles in the pathogenesis of AP and SIRS. It may be valuable to measure free radicals to predict the severity of AP.

Evaluation of beta-cell sensitivity to glucose and first-phase insulin secretion in obese dogs.

PubMed

Verkest, Kurt R; Fleeman, Linda M; Rand, Jacquie S; Morton, John M

2011-03-01

To compare beta-cell sensitivity to glucose, first-phase insulin secretion, and glucose tolerance between dogs with naturally occurring obesity of > 2 years' duration and lean dogs. 17 client-owned obese or lean dogs. Frequently sampled IV glucose tolerance tests were performed with minimal model analysis on 6 obese dogs and matched controls. Glucagon stimulation tests were performed on 5 obese dogs and matched controls. Obese dogs were half as sensitive to the effects of insulin as lean dogs. Plasma glucose concentrations after food withholding did not differ significantly between groups; plasma insulin concentrations were 3 to 4 times as great in obese as in lean dogs. Obese dogs had plasma insulin concentrations twice those of lean dogs after administration of glucose and 4 times as great after administration of glucagon. First-phase insulin secretion was greater in obese dogs. Obese dogs compensated for obesity-induced insulin resistance by secreting more insulin. First-phase insulin secretion and beta-cell glucose sensitivity were not lost despite years of obesity-induced insulin resistance and compensatory hyperinsulinemia. These findings help explain why dogs, unlike cats and humans, have not been documented to develop type 2 diabetes mellitus.

Penning trap mass spectrometry Q-value determinations for highly forbidden β-decays

NASA Astrophysics Data System (ADS)

Sandler, Rachel; Bollen, Georg; Eibach, Martin; Gamage, Nadeesha; Gulyuz, Kerim; Hamaker, Alec; Izzo, Chris; Kandegedara, Rathnayake; Redshaw, Matt; Ringle, Ryan; Valverde, Adrian; Yandow, Isaac; Low Energy Beam Ion Trap Team

2017-09-01

Over the last several decades, extremely sensitive, ultra-low background beta and gamma detection techniques have been developed. These techniques have enabled the observation of very rare processes, such as highly forbidden beta decays e.g. of 113Cd, 50V and 138La. Half-life measurements of highly forbidden beta decays provide a testing ground for theoretical nuclear models, and the comparison of calculated and measured energy spectra could enable a determination of the values of the weak coupling constants. Precision Q-value measurements also allow for systematic tests of the beta-particle detection techniques. We will present the results and current status of Q value determinations for highly forbidden beta decays. The Q values, the mass difference between parent and daughter nuclides, are measured using the high precision Penning trap mass spectrometer LEBIT at the National Superconducting Cyclotron Laboratory.

Arachidonic Acid-Induced Expression of the Organic Solute and Steroid Transporter-beta (Ost-beta) in a Cartilaginous Fish Cell Line

PubMed Central

Hwang, Jae-Ho; Parton, Angela; Czechanski, Anne; Ballatori, Nazzareno; Barnes, David

2008-01-01

The organic solute and steroid transporter (OST/Ost) is a unique membrane transport protein heterodimer composed of subunits designated alpha and beta, that transports conjugated steroids and prostaglandin E2 across the plasma membrane. Ost was first identified in the liver of the cartilaginous fish Leucoraja erinacea, the little skate, and subsequently was found in many other species, including humans and rodents. The present study describes the isolation of a new cell line, LEE-1, derived from an early embryo of L. erinacea, and characterizes the expression of Ost in these cells. The mRNA size and amino acid sequence of Ost-beta in LEE-1 was identical to that previously reported for Ost-beta from skate liver, and the primary structure was identical to that of the spiny dogfish shark (Squalus acanthias) with the exception of a single amino acid. Ost-beta was found both on the plasma membrane and intracellularly in LEE-1 cells, consistent with its localization in other cell types. Interestingly, arachidonic acid, the precursor to eiconsanoids, strongly induced Ost-beta expression in LEE-1 cells and a lipid mixture containing arachidonic acid also induced Ost-alpha. Overall, the present study describes the isolation of a novel marine cell line, and shows that this cell line expresses relatively high levels of Ost when cultured in the presence of arachidonic acid. Although the function of this transport protein in embryo-derived cells is unknown, it may play a role in the disposition of eicosanoids or steroid-derived molecules. PMID:18407792

Influence of 10 wk of soy consumption on plasma concentrations and excretion of isoflavonoids and on gut microflora metabolism in healthy adults.

PubMed

Wiseman, Helen; Casey, Karen; Bowey, Elizabeth A; Duffy, Rosanna; Davies, Margaret; Rowland, Ian R; Lloyd, Antony S; Murray, Alistair; Thompson, Richard; Clarke, Don B

2004-09-01

Little information is currently available on the role of the gut microflora in modulating isoflavone bioavailability or on sex differences in isoflavone metabolism and bioavailability. We sought to determine whether chronic soy consumption influences isoflavone bioavailability as judged by plasma isoflavone concentrations and modified gut microflora activities [beta-glucoside hydrolysis and equol and O-desmethylangolensin (O-DMA) production]. We also examined whether sex differences in isoflavone metabolism exist. A randomized, parallel, controlled study design was used to compare a high-soy diet (104 +/- 24 mg total isoflavones/d) with a low-soy diet (0.54 +/- 0.58 mg total isoflavones/d) in 76 healthy young adults for 10 wk. Concentrations of isoflavones and their gut microflora metabolites in the plasma, urine, and feces were significantly higher in the subjects who consumed the high-soy diet than in those who consumed the low-soy diet. Concentrations of O-DMA in plasma and urine were higher in the men than in the women. Fecal bacteria from subjects consuming both diets could convert daidzein to equol ex vivo. Fecal beta-glucosidase activity was significantly higher in the subjects who consumed the high-soy diet than in those who consumed the low-soy diet. Although interindividual variation in isoflavone metabolism was high, intraindividual variation was low. Only concentrations of O-DMA in plasma and urine appeared to be influenced by sex. Chronic soy consumption does not appear to induce many significant changes to the gut metabolism of isoflavones other than higher beta-glucosidase activity.

Magnetic Nozzles for Plasma Thrusters: Acceleration, Thrust, and Detachment Mechanisms

DTIC Science & Technology

2011-10-01

Energy Distribution Function M. Merino-Mart́ınez∗ Universidad Politécnica de Madrid, Spain A two-dimensional plasma beam model is used to investigate the...2D model of the supersonic expansion of a collisionless plasma in a divergent magnetic nozzle was de - veloped by Ahedo and Merino.7 An important...Universidad Politecnica de Madrid, Spain A magnetic nozzle model for the supersonic expansion of a collisionless, low-beta plasma characterizes the

Method and apparatus for maintaining equilibrium in a helical axis stellarator

DOEpatents

Reiman, Allan; Boozer, Allen

1987-01-01

Apparatus for maintaining three-dimensional MHD equilibrium in a plasma contained in a helical axis stellerator includes a resonant coil system, having a configuration such that current therethrough generates a magnetic field cancelling the resonant magnetic field produced by currents driven by the plasma pressure on any given flux surface resonating with the rotational transform of another flux surface in the plasma. Current through the resonant coil system is adjusted as a function of plasma beta.

Method and apparatus for maintaining equilibrium in a helical axis stellarator

DOEpatents

Reiman, A.; Boozer, A.

1984-10-31

Apparatus for maintaining three-dimensional MHD equilibrium in a plasma contained in a helical axis stellarator includes a resonant coil system, having a configuration such that current therethrough generates a magnetic field cancelling the resonant magnetic field produced by currents driven by the plasma pressure on any given flux surface resonating with the rotational transform of another flux surface in the plasma. Current through the resonant coil system is adjusted as a function of plasma beta.

Paraneoplastic scleroderma-like tissue reactions in the setting of an underlying plasma cell dyscrasia: a report of 10 cases.

PubMed

Magro, Cynthia M; Iwenofu, Hans; Nuovo, Gerard J

2013-07-01

Systemic plasma cell dyscrasias have diverse manifestations in the skin and include an inflammatory paraneoplastic process. We encountered cases of scleroderma and eosinophilic fasciitis in the setting of an underlying plasma cell dyscrasia. Ten cases of scleroderma-like tissue reactions in the setting of an underlying plasma cell dyscrasia were encountered. The biopsies were stained for Transforming growth factor (Transforming growth factor) beta, IgG4, kappa, and lambda. Patients presented with a sclerodermoid reaction represented by eosinophilic fasciitis (5 cases), morphea (3 cases), and systemic scleroderma (2 cases). The mean age of presentation was 70 years with a striking female predominance (4:1). Acral accentuation was noted in 8 cases. In 6 of the cases, the cutaneous sclerosis antedated (4 cases) by weeks to 2 years or occurred concurrently (2 cases) with the initial diagnosis of the plasma cell. The biopsies showed changes typical of eosinophilic fasciitis and/or scleroderma. In 5 cases, light chain-restricted plasma cells were present on the biopsy. There was staining of the plasma cells for Transforming growth factor beta in 3 out of 5 cases tested. In any older patient presenting with a sudden onset of eosinophilic fasciitis or scleroderma especially with acral accentuation, investigations should be conducted in regards to an underlying plasma cell dyscrasia.

On heat loading, novel divertors, and fusion reactors

NASA Astrophysics Data System (ADS)

Kotschenreuther, M.; Valanju, P. M.; Mahajan, S. M.; Wiley, J. C.

2007-07-01

The limited thermal power handling capacity of the standard divertors (used in current as well as projected tokamaks) is likely to force extremely high (˜90%) radiation fractions frad in tokamak fusion reactors that have heating powers considerably larger than ITER [D. J. Campbell, Phys. Plasmas 8, 2041 (2001)]. Such enormous values of necessary frad could have serious and debilitating consequences on the core confinement, stability, and dependability for a fusion power reactor, especially in reactors with Internal Transport Barriers. A new class of divertors, called X-divertors (XD), which considerably enhance the divertor thermal capacity through a flaring of the field lines only near the divertor plates, may be necessary and sufficient to overcome these problems and lead to a dependable fusion power reactor with acceptable economics. X-divertors will lower the bar on the necessary confinement to bring it in the range of the present experimental results. Its ability to reduce the radiative burden imparts the X-divertor with a key advantage. Lower radiation demands allow sharply peaked density profiles that enhance the bootstrap fraction creating the possibility for a highly increased beta for the same beta normal discharges. The X-divertor emerges as a beta-enhancer capable of raising it by up to roughly a factor of 2.

Ultrastructural localization of the C-terminus of the 43-kd dystrophin-associated glycoprotein and its relation to dystrophin in normal murine skeletal myofiber.

PubMed Central

Wakayama, Y.; Shibuya, S.; Takeda, A.; Jimi, T.; Nakamura, Y.; Oniki, H.

1995-01-01

We used single and double immunogold labeling electron microscopy to investigate ultrastructural localization of the C terminus of the 43-kd dystrophin-associated glycoprotein (43-DAG) and its relationship to dystrophin in normal murine skeletal myofibers. Single immunolabeling localized the antibody against the C terminus of 43-DAG to the inside surface of the muscle plasma membrane and the sarcoplasmic side of plasma membrane invaginations. Double immunolabeling co-localized antibodies against dystrophin and the C terminus of 43-DAG to the same site noted in the single immunolabeling localization of 43-DAG. In particular, dystrophin and the C-terminal 43-DAG antibody signals were often observed as doublets separated by less than 30 nm. We compared these results with those obtained from double immunogold labeling with anti-dystrophin and anti-beta-spectrin, as well as anti-C-terminal 43-DAG and anti-beta-spectrin antibodies. The antibodies against dystrophin and beta-spectrin, or beta-spectrin and 43-DAG, also co-localized to similar sites in skeletal muscle fibers. Signals of doublet formations were noted but their frequency was significantly lower than the doublet frequency of antidystrophin and anti-43-DAG antibodies. The results support the presence of dystrophin and 43-DAG linkage at the inside surface of the murine skeletal muscle plasma membrane. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7856727

Platelet activation in pregnancy-induced hypertension.

PubMed

Karalis, Ioannis; Nadar, Sunil K; Al Yemeni, Eman; Blann, Andrew D; Lip, Gregory Y H

2005-01-01

Although excess platelet activation, as indicated by increased plasma beta thromboglobulin (beta-TG), has been shown in pregnancy-induced hypertension (PIH), platelet adhesion, platelet morphology and a comparison of platelet and soluble (plasma) levels of the adhesion molecules P-selectin (pPsel and sPsel, respectively) have not been studied. We conducted a cross-sectional study of 35 consecutive women with PIH (age 31+/-6 years), 31 consecutive women with normotensive pregnancies (age 29+/-5 years) and 30 normotensive non pregnant women (age 30+/-5 years). Platelet adhesion was studied in vitro by binding to fibrinogen-coated microwells, platelet morphology [mass and volume by flow cytometry], whole-platelet P-selectin (pPsel) by ELISA of the lysate of 2 x 10(8) cells, and the plasma markers soluble P-selectin (sP-sel) and beta-TG, by ELISA. The women with PIH had significantly raised sPsel, pPsel and (as expected) beta-TG (all p<0.05), when compared to the normotensive pregnant women and controls. However, in PIH platelet adhesion was similar to that in the normotensive pregnancy, but still higher than the normal controls (p<0.001). There was no difference among the three groups with respect to platelet mass and volume. pPsel and platelet adhesion correlated with gestational age and with systolic and diastolic blood pressure (all p<0.05). Increased platelet activation and adhesion develop during normal pregnancy, with some indices being further altered in PIH.

Dark and grey compressional dispersive Alfven solitons in plasmas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shukla, P. K.; Eliasson, B.; Stenflo, L.

2011-06-15

The amplitude modulation of compressional dispersive Alfven (CDA) waves in a low-{beta} plasma is considered. It is shown that the dynamics of modulated CDA waves is governed by a cubic nonlinear Schroedinger equation, which depicts the formation of a dark/grey envelope CDA soliton.

Proceedings of the US-Japan Workshop on Advanced Plasma Modeling II Held in Nagoya, Japan on March 23-27, 1987

DTIC Science & Technology

1988-03-01

Ogino : An MHD Simulation Of the Solar Wind and romer -, Piasma (Nagoya Univ.) (An MHD Model with Plasma Production) C.Z.Cheng( PPPL ) : NOVA-2: A Kinetic...and Massless Fluid Electrons W.W. Lee( PPPL ) : Gyrokinetic Particle Simulation of Finite-Beta Plasma Coffee Break (10:50-11:00) Morning Session D (11

Discriminative Ability of Plasma Branched-Chain Amino Acid Levels for Glucose Intolerance in Families At Risk for Type 2 Diabetes.

PubMed

Jainandunsing, Sjaam; Wattimena, J L Darcos; Verhoeven, Adrie J M; Langendonk, Janneke G; Rietveld, Trinet; Isaacs, Aaron J; Sijbrands, Eric J G; de Rooij, Felix W M

2016-04-01

Insulin resistance and glucose intolerance have been associated with increased plasma levels of branched-chain amino acids (BCAA). BCAA levels do not predict T2DM in the population. We determined the discriminative ability of fasting BCAA levels for glucose intolerance in nondiabetic relatives of patients with T2DM of two different ethnicities. Based on oral glucose tolerance test (OGTT), first-degree relatives of patients with T2DM were categorized as normal glucose tolerance, prediabetes, or T2DM. Included were 34, 12, and 18 Caucasian and 22, 12, and 23 Asian Indian participants, respectively. BCAA levels were measured in fasting plasma together with alanine, phenylalanine, and tyrosine. Insulin sensitivity and beta-cell function were assessed by indices derived from an extended OGTT and their relationship with plasma BCAA levels was assessed in multivariate regression analysis. The value of the amino acids for discriminating prediabetes among nondiabetic family members was determined with the area under the curve of receiver-operated characteristics (c-index). BCAA levels were higher in diabetic than in normoglycemic family members in the Caucasians (P = 0.001) but not in the Asian Indians. In both groups, BCAA levels were associated with waist-hip ratio (β = 0.31; P = 0.03 and β = 0.42; P = 0.001, respectively) but not with indices of insulin sensitivity or beta-cell function. The c-index of BCAA for discriminating prediabetes among nondiabetic participants was 0.83 and 0.74 in Caucasians and Asian Indians, respectively, which increased to 0.84 and 0.79 by also including the other amino acids. The c-index of fasting glucose for discriminating prediabetes increased from 0.91 to 0.92 in Caucasians and 0.85 to 0.97 (P = 0.04) in Asian Indians by inclusion of BCAA+alanine, phenylalanine, and tyrosine. Adding fasting plasma BCAA levels, combined with phenylalanine, tyrosine and alanine to fasting glucose improved discriminative ability for the prediabetic state within Asian Indian families at risk for T2DM. BCAA levels may serve as biomarkers for early development of glucose intolerance in these families.

The metabolic syndrome X and peripheral cortisol synthesis.

PubMed

Bähr, V; Pfeiffer, A F; Diederich, S

2002-10-01

The metabolic syndrome X and Cushing's syndrome show similar symptoms but one major difference: Plasma cortisol is not elevated in the metabolic syndrome. Evidence is presented, that by the action of 11 beta-hydroxysteroid dehydrogenase 1 (11 beta HSD1) higher intracellular cortisol concentration may be created that may be relevant to induce insulin resistance and metabolic disturbances. Regulation of 11 beta HSD1 expression by hormones, growth factors, cytokines and transcription factors enables tissue specific adjustments of glucocorticoid receptor activation by cortisol. Specific inhibition of 11 beta HSD1 would help to understand aspects of the pathogenesis of syndrome X and to develop new therapeutic perspectives.

Assessment of the effects of epinephrine and insulin on plasma and serum biochemical variables in llamas and alpacas.

PubMed

Cebra, Christopher K; Tornquist, Susan J

2004-12-01

To describe the metabolic effects of epinephrine administration in New World camelids and investigate whether these effects are influenced by administration of insulin. 6 llamas and 8 alpacas (all adult castrated males). Prior to each experiment, food was withheld from camelids for 8 hours. On each of 2 consecutive days, alpacas were administered epinephrine (10 mg/kg, IM; time 0); alpacas were randomly assigned to receive regular insulin (0.2 U/kg, IV) immediately after epinephrine administration on one of those days. In llamas, the experiment was performed once after administration of epinephrine only. At 0, 30, 60, 90, 120, 150, 180, 210, and 240 minutes after treatment, blood samples were collected and several serum or plasma biochemical variables were assessed; in addition, plasma samples from llamas were assessed for insulin concentrations. Data were compared between days (alpacas only) and between time points. Administration of epinephrine induced mobilization of glucose, triglycerides, nonesterified fatty acids, and beta-hydroxybutyrate. A small increase in endogenous insulin concentration was detected in epinephrine-treated llamas, compared with baseline values. Overall, insulin administration decreased, negated, or delayed the epinephrine-associated increases in serum or plasma concentrations of circulating energy substrates, except that it augmented the epinephrine-associated increase in concentration of triglycerides. Epinephrine appeared to mobilize energy substrates in camelids and hence may be involved in the pathogenesis of disorders of glucose and fat metabolism. Insulin appeared to antagonize most of these effects, and its administration may have therapeutic value in camelids.

Interactive effects of naphthalene treatment and the onset of vitellogenesis on energy metabolism in liver and gonad, and plasma steroid hormones of rainbow trout Oncorhynchus mykiss.

PubMed

Tintos, Adrián; Gesto, Manuel; Alvarez, Rosa; Míguez, Jesús M; Soengas, José L

2006-10-01

The purpose of the study was to assess in female fish the possible interaction between treatment with a polycyclic aromatic hydrocarbon (PAH) like naphthalene and the onset of vitellogenesis. In a first experiment, female rainbow trout (Oncorhynchus mykiss) at stages 2-3 (previtellogenesis) or 4 (early vitellogenesis) were intraperitoneally injected (2 microl g(-1)) with vegetable oil alone (control) or containing naphthalene (50 mg kg(-1)) to be sampled 3 h later. A second experiment was similarly designed but using fish intraperitoneally implanted (10 microl g(-1)) with slow-release coconut oil implants alone (control) or containing 50 mg naphthalene kg(-1) body mass that were sampled 3 days after injection. On each sampling time, plasma levels of cortisol and 17beta-estradiol, and several metabolic parameters in plasma, liver and gonad were assessed. In controls, early vitellogenic fish compared with previtellogenic fish displayed changes that in some cases are confirmatory of previous studies whereas in other cases provide new information in plasma (increased amino acid levels), liver (decreased capacity for exporting glucose and reduced amino acid levels) and gonad (decreased amino acid levels). Naphthalene treatment produced in previtellogenic fish decreased 17beta-estradiol levels in plasma, increased plasma glucose or decreased liver gluconeogenic capacity whereas no major effects were noticed on parameters involved in lipid, amino acid and lactate metabolism. Differential effects of naphthalene treatment were noticed in early vitellogenic fish such as decreased 17beta-estradiol and glucose levels in plasma, increased hexokinase and glucokinase and lack of changes in fructose 1,6-bisphosphatase activities in liver, and a lower decrease of amino acid levels in gonad. Those alterations produced by naphthalene treatment resulted in a decreased capacity for covering the energy demand of vitellogenesis in liver and gonad that could contribute to a delay and/or impairment of the onset of maturation.

Electromagnetic fluctuation spectra of collective oscillations in magnetized Maxwellian plasmas for parallel wave vectors

NASA Astrophysics Data System (ADS)

Vafin, S.; Schlickeiser, R.; Yoon, P. H.

2016-05-01

The general electromagnetic fluctuation theory for magnetized plasmas is used to calculate the steady-state wave number spectra and total electromagnetic field strength of low-frequency collective weakly damped eigenmodes with parallel wavevectors in a Maxwellian electron-proton plasma. These result from the equilibrium of spontaneous emission and collisionless damping, and they represent the minimum electromagnetic fluctuations guaranteed in quiet thermal space plasmas, including the interstellar and interplanetary medium. Depending on the plasma beta, the ratio of |δB |/B0 can be as high as 10-12 .

The plasma physics of thermal conduction in the intracluster medium of galaxy clusters

NASA Astrophysics Data System (ADS)

Reynolds, Christopher

Most of the baryons in a galaxy cluster reside in a hot (10-100 million K) and tenuous gaseous atmosphere confined by the gravitational potential of the cluster's dark matter halo. Understanding the microphysics of this intracluster medium (ICM), particularly the transport processes such as thermal conduction and viscosity, is important to any understanding of the thermodynamic state of ICM atmospheres. For example, the current paradigm is that radiative losses in the ICM core are offset by energy from a central jetted active galactic nucleus (AGN), preventing a cooling catastrophe in the cluster core. However, the mechanism by which the jet-injected energy is thermalized in the ICM is highly uncertain - the dissipation of waves or turbulence by thermal conduction or plasma viscosity is a leading contender. A knowledge of thermal conduction in the ICM is also important for any attempts to understand the global temperature profiles of clusters, with consequences for e.g. cosmological studies based on observations of the SunyaevZeldovich (SZ) effect. The basic physics of thermal conduction in the ICM is very poorly understood, however, leading to a huge uncertainty in the relevant coefficients. The ICM resides in a poorly studied regime of plasma physics - it is a highly magnetized (gyroradii << particle mean free path), high-beta (thermal pressure >> magnetic pressure), and weakly collisional (mean-free path only moderately less than global scale lengths) plasma. Thermal conduction will be strongly suppressed perpendicular to magnetic fields lines. But even along field lines, the growth of small scale and fast kinetic instabilities may strongly suppress thermal conduction. Hence the usual assumption, that conduction along the field has its classical Spitzer value, has a shaky theoretical basis and may well be wildly inaccurate. In this proposal, we use analytical theory and computer models to explore thermal conduction in ICM-like plasmas. Recently, we have found that a strong heat-flux will drive a powerful whistler-wave instability and, provided we treat the problem in more than 1D so that oblique modes are captured, these waves efficiently scatter electrons thereby shutting down the heat-flux. Our proposed work builds on these findings with the goal of characterizing the macroscopic effective thermal conduction in a form that can be included in fluid (magnetohydrodynamic; MHD) models of the ICM. We will, 1) Conduct an extended linear analysis of the heat-flux whistler instability, exploring the interaction of the heat flux and the pressure anisotropies that would result from bulk motions of the ICM. We will map the stable/unstable regions as a function of heat-flux, pressure anisotropy, and plasma-beta. 2) Perform particle-in-cell (PIC) simulations to explore the non-linear saturation of the heat-flux whistler instability as a function of the plasma-beta and heat-flux, extending the current work (i.e. very strong fluxes) down to the modest heat-fluxes found in the real ICM. Key is whether overlapping wave-particle resonances that are so efficient at killing the conduction with strong heat-fluxes still operate when the driving heat-flux is weak. 3) Develop a new computational/PIC model that, in contrast to current work, sustains a temperature gradient across the domain thereby allowing us to directly measure the relationship between temperature gradient and heat flux. 4) Build a new thermal conduction model, allowing the heat flux to have a non-linear dependence on temperature gradient, and plasma-beta. We will develop thermal conduction algorithms that can be used in public MHD e.g., PLUTO or FLASH. This work will provide the crucial bridge between the global/MHD models of ICM atmospheres and the microphysics that dictates the transport processes. It will inform the next generation of cluster models used to interpret data from NASA's fleet of X-ray observatories.

Co-variables in first trimester maternal serum screening.

PubMed

de Graaf, I M; Cuckle, H S; Pajkrt, E; Leschot, N J; Bleker, O P; van Lith, J M

2000-03-01

The objective of this study was to determined the influence of maternal weight, maternal smoking habits, gravidity, parity and fetal gender on the level of maternal serum marker used in first trimester screening for Down syndrome. A total of 2449 singleton unaffected pregnancies from two centres were studied. Maternal serum free beta-human chorionic gonadotrophin (hCG) and alpha-fetoprotein (AFP) concentrations had been measured in all pregnancies, and pregnancy associated plasma protein (PAPP)-A levels had been measured in 924. All results were expressed as multiples of the gestation specific median (MoM) values after regression, using each centre's own medians. Information on maternal weight was available in 2259 pregnancies, on self-reported current cigarette smoking in 1364 (of whom 117 (8.6%) were smokers), on gravidity in 1371, parity in 1303 and fetal gender in 253. All three markers showed a statistically significant negative association with maternal weight (p<0.0005) and in the subsequent analyses MoM values were weight adjusted using standard methods. The median PAPP-A level in smokers was 0.81 MoM, a significant reduction (p<0.005); free beta-hCG was also reduced (median 0.89 MoM) but not significantly (p=0.17), and AFP was unaltered. The median AFP level in primagravidas was highly significantly greater than that in gravid women (p<0.0005). In PAPP-A the reverse effect was seen but it did not reach statistical significance (p=0.15) and there was no effect for free beta-hCG. Results of a similar magnitude and direction were found for parity. The median level of free beta-hCG was higher (p=0.0005), and the median AFP lower in female pregnancies. Maternal weight and, for PAPP-A, maternal smoking are important first trimester screening co-variables. Gravidity, parity and fetal gender also seem to influence one or more first trimester markers. Copyright 2000 John Wiley & Sons, Ltd.

The study of IL-1 beta, TNF-alpha, IL-6 gene expression and plasma levels on hemodialysis before and after dialyzer reuse.

PubMed

Qian, J; Yu, Z; Dai, H; Huang, P; Zhang, Q; Cheng, F; Chen, S

1997-07-01

To investigate the biocompatibility of dialyzer reuse. Twenty-two hemodialysis patients were randomized into cuprophan (CU, 7), polymethylmethacrylate (PMMA, 7) and polysulphone (PS, 8) membrane groups to observe IL-1 beta, TNF-alpha, IL-6 gene expression and their plasma levels by using themselves as control with enzyme-linked immunosorbent assay (ELISA), reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization. Plasma levels of interlukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) were 14.07 +/- 3.32 pg/ml, 67.41 +/- 19.79 pg/ml, 83.67 +/- 40.34 pg/ml; 12.80 +/- 3.01 pg/ml, 49.65 +/- 9.75 pg/ml, 33.36 +/- 12.14 pg/ml and 14.41 +/- 3.16 pg/ml, 80.56 +/- 23.22 pg/ml, 48.14 +/- 16.01 pg/ml, respectively, after patients dialyzed with CU, PMMA and PS membranes. Plasma cytokine levels decreased after reuse compared with those before reuse in each group. But no significant difference was found between them (P > 0.05); the levels of IL-1 beta, TNF-alpha, IL-6 gene expression after reuse were 5.61 +/- 0.33, 2.11 +/- 0.12, 5.04 +/- 0.19%; 2.43 +/- 0.19, 1.29 +/- 0.11, 3.48 +/- 0.20% and 2.48 +/- 0.20, 1.24 +/- 0.11, 3.22 +/- 0.20% respectively by in situ hybridization, and 0.92 +/- 0.07, 0.63 +/- 0.05, 0.53 +/- 0.05; 0.61 +/- 0.06, 0.47 +/- 0.04, 0.37 +/- 0.03 and 0.59 +/- 0.05, 0.44 +/- 0.04, 0.38 +/- 0.03 by RT-PCR, respectively. After reuse there was significant decrease as compared with that before reuse (P < 0.001, P < 0.005 and P < 0.05, respectively). This suggested reprocessing dialyzer with formaldehyde reduced cytokine release and gene expression in peripheral blood mononuclear cells and enhanced dialyzer biocompatibility. It would be beneficial to reduce the dialysis cost and may reduce the complication related to a long term hemodialysis.

Quantitative Assessment of Proliferative Effects of Oral Vanadium on Pancreatic Islet Volumes and Beta Cell Numbers of Diabetic Rats.

PubMed

Pirmoradi, Leila; Noorafshan, Ali; Safaee, Akbar; Dehghani, Gholam Abbas

2016-01-01

Oral vanadyl sulfate (vanadium) induces normoglycemia, proliferates beta cells and prevents pancreatic islet atrophy in streptozotocin-induced diabetic rats. Soteriological method is used to quantitate the proliferative effects of vanadium on beta-cell numbers and islet volumes of normal and diabetic rats. Adult male Sprague-Dawley rats were made diabetic with intravenous streptozotocin injection (40 mg/kg). Normal and diabetic rats were divided into four groups. While control normal and diabetic (CD) groups used water, vanadium-treated normal (VTN) and diabetic (VTD) groups used solutions containing vanadyl sulfate (0.5-1 mg/mL, VOSO4+5H2O). Tail blood samples were used to measure blood glucose (BG) and plasma insulin. Two months after treatment, rats were sacrificed, pancreata prepared, and stereology method was used to quantitatively evaluate total beta cell numbers (TBCN) and total islet volumes (TISVOL). Normoglycemia persisted in VTN with significantly decreased plasma insulin (0.19±0.08 vs. 0.97±0.27 ng/dL, P<0.002). The respective high BG (532±49 vs. 144±46 mg/dL, P<0.0001) and reduced plasma insulin (0.26±0.15 vs. 0.54±0.19 ng/dL, P<0.002) seen in CD were reversed in VTD during vanadium treatment or withdrawal. While the induction of diabetes, compared to their control, significantly decreased TISVOL (1.9±0.2 vs. 3.03±0.6 mm3, P<0.003) and TBCN (0.99±0.1 vs. 3.2±0.2 x 106, P<0.003), vanadium treatment significantly increased TISVOL (2.9±0.8 and 4.07±1.0 mm3, P<0.003) and TBCN (1.5±0.3 and 3.8±0.6 x 106, P<0.03). Two-month oral vanadium therapy in STZ-diabetic rats ameliorated hyperglycemia by partially restoring plasma insulin. This action was through proliferative actions of vanadium in preventing islet atrophy by increasing beta-cell numbers.

The role of the anterodorsal thalami nuclei in the regulation of adrenal medullary function, beta-adrenergic cardiac receptors and anxiety responses in maternally deprived rats under stressful conditions.

PubMed

Suárez, M M; Rivarola, M A; Molina, S M; Levin, G M; Enders, J; Paglini, P

2004-09-01

Maternal separation can interfere with growth and development of the brain and represents a significant risk factor for adult psychopathology. In rodents, prolonged separation from the mother affects the behavioral and endocrine responses to stress for the lifetime of the animal. Limbic structures such as the anterodorsal thalamic nuclei (ADTN) play an important role in the control of neuroendocrine and sympathetic-adrenal function. In view of these findings we hypothesized that the function of the ADTN may be affected in an animal model of maternal deprivation. To test this hypothesis female rats were isolated 4.5 h daily, during the first 3 weeks of life and tested as adults. We evaluated plasma epinephrine (E) and norepinephrine (NE), cardiac adrenoreceptors and anxiety responses after maternal deprivation and variable chronic stress (VCS) in ADTN-lesioned rats. Thirty days after ADTN lesion, in non-maternally deprived rats basal plasma NE concentration was greater and cardiac beta-adrenoreceptor density was lower than that in the sham-lesioned group. Maternal deprivation induced a significant increase in basal plasma NE concentration, which was greater in lesioned rats, and cardiac beta-adrenoreceptor density was decreased in lesioned rats. After VCS plasma catecholamine concentration was much greater in non-maternally deprived rats than in maternally-deprived rats; cardiac beta-adrenoreceptor density was decreased by VCS in both maternally-deprived and non-deprived rats, but more so in non-deprived rats, and further decreased by the ADTN lesion. In the plus maze test, the number of open arm entries was greater in the maternally deprived and in the stressed rats. Thus, sympathetic-adrenal medullary activation produced by VCS was much greater in non-deprived rats, and was linked to a down regulation of myocardial beta-adrenoceptors. The ADTN are not responsible for the reduced catecholamine responses to stress in maternally-deprived rats. Maternal deprivation or chronic stress also induced a long term anxiolytic effect, which was also not affected by ADTN lesion.

Effects of N-acetylcysteine and tirilazad mesylate on intestinal functional capillary density, leukocyte adherence, mesenteric plasma extravasation and cytokine levels in experimental endotoxemia in rats.

PubMed

Birnbaum, J; Lehmann, Ch; Klotz, E; Hein, O Vargas; Blume, A; Jubin, F; Polze, N; Luther, D; Spies, C D

2008-01-01

The study's objective was to determine the effects of the administration of N-acetylcysteine (NAC) and of tirilazad mesylate (TM) on intestinal functional capillary density, mesenteric plasma extravasation, leukocyte adherence and on cytokine release during experimental endotoxemia in rats. In a prospective, randomized, controlled animal study, 80 male Wistar rats were examined in 2 test series. Both series were divided into 4 groups. Group 1 served as control group (CON group). Group 2 (LPS group), group 3 (NAC group) and group 4 (TM group) received endotoxin infusions (10 mg/kg over 2 h). In NAC group 150 mg/kg body weight NAC was administered after the first 30 minutes of endotoxemia intravenously. In TM group, 10 mg/kg body weight TM was administered after the first 30 minutes of endotoxemia intravenously. Animals of the series 1 underwent studies of leukocyte adherence on submucosal venular endothelium of the small bowel wall and intestinal functional capillary density (FCD) in the intestinal mucosa and the circular as well as the longitudinal muscle layer by intravital fluorescence microscopy (IVM). Plasma levels of interleukin 1beta (IL-1beta), interferone gamma (IFN-gamma) and soluble intercellular adhesion molecule1 (s-ICAM 1) as well as white blood cell count (WBC) were estimated. In the animals of the series 2 mesenteric plasma extravasation was determined by IVM and plasma levels of tumor necrosis factor alpha (TNF-alpha), IL-4, IL-6, IL-10 and malondialdehyde (MDA) were estimated. After LPS administration, FCD in the villi intestinales was unchanged and in the longitudinal muscularis layer it was increased. There was no effect of NAC or TM administration on FCD.Although the plasma extravasation was not significantly influenced by LPS administration, TM administration resulted in a lower plasma extravasation in the TM group compared to the other groups. After endotoxin challenge, the firmly adherence of leukocytes to vascular endothelium as a parameter of leukocyte activation in endotoxemia was increased but NAC or TM administration had no influence on leukocyte adherence. The plasma levels of IL-1beta, IL-6, IL-10, TNF-alpha, IFN-gamma and sICAM-1 were increased in the endotoxemic groups (LPS group, NAC group and TM group) and the WBC was decreased compared to controls. IL-4 levels were unchanged during observation period. Plasma MDA levels were not influenced by LPS administration compared to controls. The administration of NAC resulted in lower sICAM-1 and MDA levels compared to the LPS group. The IL-1beta, IL-6, IL-10, TNF-alpha and IFN-gamma plasma levels were not influenced by NAC or TM administration. In this posttreatment sepsis model in rats, NAC administration resulted in lower sICAM-1 and MDA levels compared to the LPS treated animals. TM administration reduced the plasma extravasation in this model.

Calmodulin-dependent gating of Ca(v)1.2 calcium channels in the absence of Ca(v)beta subunits.

PubMed

Ravindran, Arippa; Lao, Qi Zong; Harry, Jo Beth; Abrahimi, Parwiz; Kobrinsky, Evgeny; Soldatov, Nikolai M

2008-06-10

It is generally accepted that to generate calcium currents in response to depolarization, Ca(v)1.2 calcium channels require association of the pore-forming alpha(1C) subunit with accessory Ca(v)beta and alpha(2)delta subunits. A single calmodulin (CaM) molecule is tethered to the C-terminal alpha(1C)-LA/IQ region and mediates Ca2+-dependent inactivation of the channel. Ca(v)beta subunits are stably associated with the alpha(1C)-interaction domain site of the cytoplasmic linker between internal repeats I and II and also interact dynamically, in a Ca2+-dependent manner, with the alpha(1C)-IQ region. Here, we describe a surprising discovery that coexpression of exogenous CaM (CaM(ex)) with alpha(1C)/alpha(2)delta in COS1 cells in the absence of Ca(v)beta subunits stimulates the plasma membrane targeting of alpha(1C), facilitates calcium channel gating, and supports Ca2+-dependent inactivation. Neither real-time PCR with primers complementary to monkey Ca(v)beta subunits nor coimmunoprecipitation analysis with exogenous alpha(1C) revealed an induction of endogenous Ca(v)beta subunits that could be linked to the effect of CaM(ex). Coexpression of a calcium-insensitive CaM mutant CaM(1234) also facilitated gating of Ca(v)beta-free Ca(v)1.2 channels but did not support Ca2+-dependent inactivation. Our results show there is a functional matchup between CaM(ex) and Ca(v)beta subunits that, in the absence of Ca(v)beta, renders Ca2+ channel gating facilitated by CaM molecules other than the one tethered to LA/IQ to support Ca2+-dependent inactivation. Thus, coexpression of CaM(ex) creates conditions when the channel gating, voltage- and Ca2+-dependent inactivation, and plasma-membrane targeting occur in the absence of Ca(v)beta. We suggest that CaM(ex) affects specific Ca(v)beta-free conformations of the channel that are not available to endogenous CaM.

Reliability of Beta angle in assessing true anteroposterior apical base discrepancy in different growth patterns

PubMed Central

Sundareswaran, Shobha; Kumar, Vinay

2015-01-01

Introduction: Beta angle as a skeletal anteroposterior dysplasia indicator is known to be useful in evaluating normodivergent growth patterns. Hence, we compared and verified the accuracy of Beta angle in predicting sagittal jaw discrepancy among subjects with hyperdivergent, hypodivergent and normodivergent growth patterns. Materials and Methods: Lateral cephalometric radiographs of 179 patients belonging to skeletal Classes I, II, and III were further divided into normodivergent, hyperdivergent, and hypodivergent groups based on their vertical growth patterns. Sagittal dysplasia indicators - angle ANB, Wits appraisal, and Beta angle values were measured and tabulated. The perpendicular point of intersection on line CB (Condylion-Point B) in Beta angle was designated as ‘X’ and linear dimension XB was evaluated. Results: Statistically significant increase was observed in the mean values of Beta angle and XB distance in the vertical growth pattern groups of both skeletal Class I and Class II patients thus pushing them toward Class III and Class I, respectively. Conclusions: Beta angle is a reliable indicator of sagittal dysplasia in normal and horizontal patterns of growth. However, vertical growth patterns significantly increased Beta angle values, thus affecting their reliability as a sagittal discrepancy assessment tool. Hence, Beta angle may not be a valid tool for assessment of sagittal jaw discrepancy in patients exhibiting vertical growth patterns with skeletal Class I and Class II malocclusions. Nevertheless, Class III malocclusions having the highest Beta angle values were unaffected. PMID:25810649

Simultaneous measurements of magnetotail dynamics by IMP spacecraft

NASA Technical Reports Server (NTRS)

Fairfield, D. H.; Lepping, R. P.; Hones, E. W., Jr.; Bame, S. J.; Asbridge, J. R.

1980-01-01

Changes in tail energy density during substorms in the magnetotail are given. In addition to plasma sheet thinnings seen prior to substorm onsets, a gradual decrease in plasma beta was detected in the deep tail which precedes onset and the more prominent plasma disappearance that typically accompanies it. The frequency of thinnings and the regions over which they occurred indicate that drastic changes in plasma sheet thickness are common features of substorms which occur at all locations across the tail.

Oxidative stress and antioxidants in athletes undertaking regular exercise training.

PubMed

Watson, Trent A; MacDonald-Wicks, Lesley K; Garg, Manohar L

2005-04-01

Exercise has been shown to increase the production of reactive oxygen species to a point that can exceed antioxidant defenses to cause oxidative stress. Dietary intake of antioxidants, physical activity levels, various antioxidants and oxidative stress markers were examined in 20 exercise-trained "athletes" and 20 age- and sex-matched sedentary "controls." Plasma F2-isoprostanes, antioxidant enzyme activities, and uric acid levels were similar in athletes and sedentary controls. Plasma alpha-tocopherol and beta-carotene were higher in athletes compared with sedentary controls. Total antioxidant capacity tended to be lower in athletes, with a significant difference between male athletes and male controls. Dietary intakes of antioxidants were also similar between groups and well above recommended dietary intakes for Australians. These findings suggest that athletes who consume a diet rich in antioxidants have elevated plasma alpha-tocopherol and beta-carotene that were likely to be brought about by adaptive processes resulting from regular exercise.

High temperature plasma in beta Lyrae, observed from Copernicus

NASA Technical Reports Server (NTRS)

Kondo, Y.; Hack, M.; Hutchings, J. B.; Mccluskey, G. E., Jr.; Plavec, M.; Polidan, R. S.

1975-01-01

High-resolution UV spectrophotometry of the complex close binary system beta Lyrae was performed with a telescope spectrometer on board Copernicus. Observations were made at phases 0.0, 0.25, 0.5, and 0.75 with resolutions of 0.2 A (far-UV) and 0.4 A (mid-UV). The far-UV spectrum is completely dominated by emission lines indicating the existence of a high-temperature plasma in this binary. The spectrum of this object is unlike that of any other object observed from Copernicus. It is believed that this high-temperature plasma results from dynamic mass transfer taking place in the binary. The current results are compared with OAO-2 observations and other observational results. The possibility that the secondary component is a collapsed object is also discussed; the Copernicus observations are consistent with the hypothesis that the spectroscopically invisible secondary component is a black hole.

Observations of mirror waves and plasma depletion layer upstream of Saturn's magnetopause

NASA Technical Reports Server (NTRS)

Violante, L.; Cattaneo, M. B. Bavassano; Moreno, G.; Richardson, J. D.

1995-01-01

The two inbound traversals of the Saturn's magnetosheath by Voyagers 1 and 2 have been studied using plasma and magnetic field data. In a great portion of the subsolar magnetosheath, large-amplitude compressional waves are observed at low frequency (approximately 0.1 f(sub p)) in a high-beta plasma regime. The fluctuations of the magnetic field magnitude and ion density are anticorrelated, as are those of the magnetic and thermal pressures. The normals to the structures are almost orthogonal to the background field, and the Doppler ratio is on the average small. Even though the data do not allow the determination of the ion thermal anisotropy, the observations are consistent with values of T(sub perpendicular)/T(sub parallel) greater than 1, producing the onset of the mirror instability. All the above features indicate that the waves should be most probably identified with mirror modes. One of the two magnetopause crossings is of the high-shear type and the above described waves are seen until the magnetopause. The other crossing is of the low-shear type and, similarly to what has been observed at Earth, a plasma depletion occurs close to the magnetopause. In this layer, waves with smaller amplitude, presumably of the mirror mode, are present together with higher-frequency waves showing a transverse component.

Implications of depleted flux tubes in the Jovian magnetosphere

NASA Astrophysics Data System (ADS)

Russell, C. T.; Kivelson, M. G.; Kurth, W. S.; Gurnett, D. A.

2000-10-01

A rare but persistent phenomenon in the jovian magnetosphere is the occurrence of apparently depleted flux tubes, whose magnetic pressures are significantly above ambient levels. These flux tubes occur about 0.25% of the observing time in the region of the Io torus in the Galileo high resolution data. The importance of these tubes is that they can return to the inner magnetosphere the magnetic flux that has been convected radially outward with the iogenic plasma to the tail. The paucity of these tubes is consistent with the expected flux return rates if the tubes are moving inward at an average rate of about 5-10 km/s in the torus. Depleted flux tubes have yet to be observed inside of the Io orbit where the plasma beta is lower than in the hot torus. Estimates of the plasma density outside the tube from plasma wave measurements enable the average perpendicular temperature to be obtained from the magnetic field change. Extrapolating this temperature back to Io, we obtain an average ion temperature of approximately 60 eV. These values are generally consistent with earlier Voyager observations but on the low side of their range of uncertainty, and agree quite well with contemporaneous Galileo measurements where these are available.

Implications of Depleted flux Tubes in the Jovian Magnetosphere

NASA Technical Reports Server (NTRS)

Russell, C. T.; Kivelson, M. G.; Kurth, W. S.; Gurnett, D. A.

2000-01-01

A rare but persistent phenomenon in the jovian magnetosphere is the occurrence of apparently depleted flux tubes, whose magnetic pressures are significantly above ambient levels. These flux tubes occur about 0.25% of the observing time in the region of the Io torus in the Galileo high resolution data. The importance of these tubes is that they can return to the inner magnetosphere the magnetic flux that has been convected radially outward with the iogenic plasma to the tail. The paucity of these tubes is consistent with the expected flux return rates if the tubes are moving inward at an average rate of about 5-10 km/s in the torus. Depleted flux tubes have yet to be observed inside of the lo orbit where the plasma beta is lower than in the hot torus. Estimates of the plasma density outside the tube from plasma wave measurements enable the average perpendicular temperature to be obtained from the magnetic field change. Extrapolating this temperature back to lo, we obtain an average ion temperature of approximately 60 eV. These values are generally consistent with earlier Voyager observations but on the low side of their range of uncertainty, and agree quite well with contemporaneous Galileo measurements where these are available.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qian, Jinping P.; Garofalo, Andrea M.; Gong, Xianzu Z.

Recent EAST/DIII-D joint experiments on the high poloidal betamore » $${{\\beta}_{\\text{P}}}$$ regime in DIII-D have extended operation with internal transport barriers (ITBs) and excellent energy confinement (H 98y2 ~ 1.6) to higher plasma current, for lower q 95 ≤ 7.0, and more balanced neutral beam injection (NBI) (torque injection < 2 Nm), for lower plasma rotation than previous results. Transport analysis and experimental measurements at low toroidal rotation suggest that the E × B shear effect is not key to the ITB formation in these high $${{\\beta}_{\\text{P}}}$$ discharges. Experiments and TGLF modeling show that the Shafranov shift has a key stabilizing effect on turbulence. Extrapolation of the DIII-D results using a 0D model shows that with the improved confinement, the high bootstrap fraction regime could achieve fusion gain Q = 5 in ITER at $${{\\beta}_{\\text{N}}}$$ ~ 2.9 and q 95 ~ 7. With the optimization of q(0), the required improved confinement is achievable when using 1.5D TGLF-SAT1 for transport simulations. Furthermore, results reported in this paper suggest that the DIII-D high $${{\\beta}_{\\text{P}}}$$ scenario could be a candidate for ITER steady state operation.« less

Compatibility of internal transport barrier with steady-state operation in the high bootstrap fraction regime on DIII-D

DOE PAGES

Garofalo, Andrea M.; Gong, Xianzu; Grierson, Brian A.; ...

2015-11-16

Recent EAST/DIII-D joint experiments on the high poloidal beta tokamak regime in DIII-D have demonstrated fully noninductive operation with an internal transport barrier (ITB) at large minor radius, at normalized fusion performance increased by ≥30% relative to earlier work. The advancement was enabled by improved understanding of the “relaxation oscillations”, previously attributed to repetitive ITB collapses, and of the fast ion behavior in this regime. It was found that the “relaxation oscillations” are coupled core-edge modes 2 amenable to wall-stabilization, and that fast ion losses which previously dictated a large plasma-wall separation to avoid wall over-heating, can be reduced tomore » classical levels with sufficient plasma density. By using optimized waveforms of the plasma-wall separation and plasma density, fully noninductive plasmas have been sustained for long durations with excellent energy confinement quality, bootstrap fraction ≥ 80%, β N ≤ 4 , β P ≥ 3 , and β T ≥ 2%. Finally, these results bolster the applicability of the high poloidal beta tokamak regime toward the realization of a steady-state fusion reactor.« less

Particle acceleration during magnetic reconnection in a low-beta pair plasma

DOE PAGES

Guo, Fan; Li, Hui; Daughton, William; ...

2016-04-29

Plasma energization through magnetic reconnection in the magnetically dominated regime featured by low plasma beta (β=8πnkT0/B 2 <<1) and/or high magnetization (σ=B 2/(4πnmc 2)>>1) is important in a series of astrophysical systems such as solar flares, pulsar wind nebula, and relativistic jets from black holes. In this paper, we review the recent progress on kinetic simulations of this process and further discuss plasma dynamics and particle acceleration in a low-β reconnection layer that consists of electron–positron pairs. We also examine the effect of different initial thermal temperatures on the resulting particle energy spectra. While earlier papers have concluded that themore » spectral index is smaller for higher σ, our simulations show that the spectral index approaches p = 1 for sufficiently low plasma β, even if σ~1. Since this predicted spectral index in the idealized limit is harder than most observations, it is important to consider effects that can lead to a softer spectrum such as open boundary simulations. Here, we also remark that the effects of three-dimensional reconnection physics and turbulence on reconnection need to be addressed in the future.« less

Plasma Membrane Protein Profiling in Beta-Amyloid-Treated Microglia Cell Line.

PubMed

Correani, Virginia; Di Francesco, Laura; Mignogna, Giuseppina; Fabrizi, Cinzia; Leone, Stefano; Giorgi, Alessandra; Passeri, Alessia; Casata, Roberto; Fumagalli, Lorenzo; Maras, Bruno; Schininà, M Eugenia

2017-09-01

In the responsiveness of microglia to toxic stimuli, plasma membrane proteins play a key role. In this study we treated with a synthetic beta amyloid peptide murine microglial cells metabolically differently labelled with stable isotope amino acids (SILAC). The plasma membrane was selectively enriched by a multi-stage aqueous two-phase partition system. We were able to identify by 1D-LC-MS/MS analyses 1577 proteins, most of them are plasma membrane proteins according to the Gene Ontology annotation. An unchanged level of amyloid receptors in this data set suggests that microglia preserve their responsiveness capability to the environment even after 24-h challenge with amyloid peptides. On the other hand, 14 proteins were observed to change their plasma membrane abundance to a statistically significant extent. Among these, we proposed as reliable biomarkers of the inflammatory microglia phenotype in AD damaged tissues MAP/microtubule affinity-regulating kinase 3 (MARK3), Interferon-induced transmembrane protein 3 (IFITM3), Annexins A5 and A7 (ANXA5, ANXA7) and Neuropilin-1 (NRP1), all proteins known to be involved in the inflammation processes and in microtubule network assembly rate. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Particle acceleration during magnetic reconnection in a low-beta pair plasma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guo, Fan; Li, Hui; Daughton, William

Plasma energization through magnetic reconnection in the magnetically dominated regime featured by low plasma beta (β=8πnkT0/B 2 <<1) and/or high magnetization (σ=B 2/(4πnmc 2)>>1) is important in a series of astrophysical systems such as solar flares, pulsar wind nebula, and relativistic jets from black holes. In this paper, we review the recent progress on kinetic simulations of this process and further discuss plasma dynamics and particle acceleration in a low-β reconnection layer that consists of electron–positron pairs. We also examine the effect of different initial thermal temperatures on the resulting particle energy spectra. While earlier papers have concluded that themore » spectral index is smaller for higher σ, our simulations show that the spectral index approaches p = 1 for sufficiently low plasma β, even if σ~1. Since this predicted spectral index in the idealized limit is harder than most observations, it is important to consider effects that can lead to a softer spectrum such as open boundary simulations. Here, we also remark that the effects of three-dimensional reconnection physics and turbulence on reconnection need to be addressed in the future.« less

Amoxicillin-potassium clavulanate: a novel beta-lactamase inhibitor.

PubMed

Smith, B R; LeFrock, J L

1985-06-01

Potassium clavulanate is a novel beta-lactamase inhibitor, which, in combination, expands the spectrum of amoxicillin to include many amoxicillin-resistant organisms. Potassium clavulanate is excreted 30-50 percent unchanged renally and its plasma time-course parallels that of amoxicillin. Several studies suggest that an increased incidence of gastrointestinal side effects may occur with this combination. In the current oral formulation, its greatest utility may be in pediatric infections due to beta-lactamase-producing Haemophilus influenzae and B. cattarhalis. In adults, the combination has not been adequately studied against other effective antibiotics.

Forbidden Mass Ranges for Shower Meteoroids

NASA Technical Reports Server (NTRS)

Moorhead, Althea V.

2017-01-01

Burns et al. (1979) use the parameter beta to describe the ratio of radiation pressure to gravity for a particle in the Solar System. The central potential that these particles experience is effectively reduced by a factor of (1- beta ), which in turn lowers the escape velocity. Burns et al. (1979) derived a simple expression for the value of beta at which particles ejected from a comet follow parabolic orbits and thus leave the Solar System; we expand on this to derive an expression for critical beta values that takes ejection velocity into account, assuming geometric optics. We use our expression to compute the critical value and corresponding mass for cometary ejecta leading, trailing, and following the parent comet's nucleus for 10 major meteor showers. Finally, we numerically solve for critical beta values in the case of non-geometric optics. These values determine the mass regimes within which meteoroids are ejected from the Solar System and therefore cannot contribute to meteor showers.

Ohmic ignition with high engineering beta based on the RFP

NASA Astrophysics Data System (ADS)

Sarff, J. S.; Anderson, J. K.; Chapman, B. E.; McCollam, K. J.

2017-10-01

The RFP configuration allows the possibility of ohmic ignition for fusion energy, eliminating the need for auxiliary heating by rf or neutral beam injection. Complex plasma-facing antennas and NBI sources are therefore not required, simplifying the difficult fusion materials challenge. While all toroidal configurations require a volume-average 〈 B 〉 >= 5 T, the field strength at the magnet in the RFP is only Bcoil 3T since plasma current generates almost all of the field. Engineering beta is therefore maximized. We summarize access to ohmic ignition by examining a Lawson-like power balance for an RFP fusion plasma comparable to the ARIES-AT advanced tokamak, which generates neutron wall loading Pn / A 5 MW/m2. The required energy confinement for ohmic ignition in an RFP is similar to that for a tokamak. Confinement in MST is comparable to a same-size, same-field tokamak plasma, but 〈 B 〉 in MST is only 1/20th that required for fusion. While transport could ultimately be dominated by micro turbulence, extrapolation of stochastic transport using Lundquist number scaling for MHD tearing indicates standard RFP confinement (not enhanced by current profile control) could be sufficient to access ohmic ignition. This bolsters the possibility for steady-state inductive sustainment using oscillating field current drive. The high beta and classical energetic ion confinement measured in MST also bolster the RFP's fusion potential. Work supported by U.S. DoE.

Deglycosylation of serum vitamin D3-binding protein by alpha-N-acetylgalactosaminidase detected in the plasma of patients with systemic lupus erythematosus.

PubMed

Yamamoto, N; Naraparaju, V R; Moore, M; Brent, L H

1997-03-01

A serum glycoprotein, Gc protein (vitamin D3-binding protein), can be converted by beta-galactosidase of B cells and sialidase of T cells to a potent macrophage-activating factor (MAF), a protein with N-acetylgalactosamine as the remaining sugar moiety. Thus, Gc protein is the precursor for MAF. Treatment of Gc protein with immobilized beta-galactosidase and sialidase generates a remarkably high titered macrophage-activating factor (GcMAF). When peripheral blood monocytes/ macrophages (designated macrophages) of 33 systemic lupus erythematosus patients were incubated with GcMAF (100 pg/ml), the macrophages of all patients were activated as determined by superoxide generation. However, the precursor activity of patient plasma Gc protein was lost or reduced in these patients. Loss of the precursor activity was the result of deglycosylation of plasma Gc protein by alpha-N-acetylgalactosaminidase activity found in the patient plasma. Levels of plasma alpha-N-acetylgalactosaminidase activity in individual patients had an inverse correlation with the MAF precursor activity of their plasma Gc protein. Deglycosylated Gc protein cannot be converted to macro-phage-activating factor. The resulting defect in macro-phage activation may lead to an inability to clear pathogenic immune complexes. Thus, elevated plasma alpha-N-acetylgalactosaminidase activity resulting in the loss of MAF precursor activity and reduced macro-phage activity may play a role in the pathogenesis of systemic lupus erythematosus.

Effect of spark plasma sintering on the microstructure and in vitro behavior of plasma sprayed HA coatings.

PubMed

Yu, L-G; Khor, K A; Li, H; Cheang, P

2003-07-01

The crystalline phases and degree of crystallinity in plasma sprayed calcium phosphate coatings on Ti substrates are crucial factors that influence the biological interactions of the materials in vivo. In this study, plasma sprayed hydroxyapatite (HA) coatings underwent post-spray treatment by the spark plasma sintering (SPS) technique at 500 degrees C, 600 degrees C, and 700 degrees C for duration of 5 and 30 min. The activity of the HA coatings before and after SPS are evaluated in vitro in a simulated body fluid. The surface microstructure, crystallinity, and phase composition of each coating is characterized by scanning electron microscopy and X-ray diffractometry before, and after in vitro incubation. Results show that the plasma sprayed coatings treated for 5 min in SPS demonstrated increased proportion of beta-TCP phase with a preferred-orientation in the (214) plane, and the content of beta-TCP phase corresponded to SPS temperature, up to 700 degrees C. SPS treatment at 700 degrees C for 30 min enhanced the HA content in the plasma spray coating as well. The HA coatings treated in SPS for 5 min revealed rapid surface morphological changes during in vitro incubation (up to 12 days), indicating that the surface activity is enhanced by the SPS treatment. The thickest apatite layer was found in the coating treated by SPS at 700 degrees C for 5 min.

Plasma growth hormone, insulin, and glucagon responses to arginine infusion in children and adolescents with idiopathic short stature, isolated growth hormone deficiency, panhypopituitarism, and anorexia nervosa.

PubMed

Sizonenko, P C; Rabinovitch, A; Schneider, P; Paunier, L; Wollheim, C B; Zahnd, G

1975-09-01

The effects of intravenous infusion of arginine (20 g/m2) after an overnight fast on plasma immunoreactive growth hormone (GH), insulin (IRI), and glucagon (IRG), and blood glucose were examined in five groups of children and adolescents: 10 normal individuals, 18 with idiopathic short stature, 6 with isolated growth hormone deficiency, 8 with panhypopituitarism, and 6 with anorexia nervosa. The mean fasting plasma GH concentration was significantly elevated in the group with anorexia nervosa (P less than 0.05), and similar to the value for the normal group in all other groups. After arginine infusion, four- to sixfold increases of plasma GH were observed in the normal children, and similar increases were seen in those with idiopathic short stature as well as in those with anorexia nervosa; whereas, in the children with isolated growth hormone deficiency or panhypopituitarism, there was no significant increase in plasma GH. Fasting blood glucose concentrations were significantly lower than normal in subjects with isolated growth hormone deficiency (P less than 0.05), panhypopituitarism (P less than 0.001), and anorexia nervosa (P less than 0.001), whereas fasting plasma IRI and IRG concentrations were similar to the values in the normal group. Plasma IRI increased eightfold at the end of the 30-min arginine infusion in the normal subjects; the increase was slightly but not significantly less in those with idiopathic short stature, and significantly less in those with isolated growth hormone deficiency (P less than 0.05), panhypopituitarism (P less than 0.001), and anorexia nervosa (P less than 0.05). Arginine infusion resulted in two- to threefold increases of plasma IRG in the normal group, and similar increases were observed in all of the other groups tested. These results suggest that whereas pancreatic beta cell responsiveness may be deficient in children and adolescents with isolated growth hormone deficiency, panhypopituitarism, or anorexia nervosa, pancreatic alpha cell responsiveness, to arginine at least, appears to be intact under these conditions.

Molecular cloning of a small prostate protein, known as beta-microsemenoprotein, PSP94 or beta-inhibin, and demonstration of transcripts in non-genital tissues.

PubMed

Ulvsbäck, M; Lindström, C; Weiber, H; Abrahamsson, P A; Lilja, H; Lundwall, A

1989-11-15

In order to study the gene expression of the seminal plasma protein beta-microseminoprotein, also known as PSP94 and beta-inhibin, clones encoding this protein were isolated from a cDNA library constructed in lambda gt11. Nucleotide sequencing confirmed the structure of a previously cloned cDNA. By northern blot analysis identical sized transcripts were demonstrated in the prostate, the respiratory (tracheal, bronchial and lung) tissues and the antrum part of the gastric mucosa. Thus, the protein is not primarily associated with male reproductive function. Although probably of no physiological significance, a slight structural similarity to the ovarian inhibin beta-chains was identified in the C-terminal half of the molecule.

Purification and characterization of NADP-dependent 7 beta-hydroxysteroid dehydrogenase from Peptostreptococcus productus strain b-52.

PubMed

Masuda, N; Oda, H; Tanaka, H

1983-01-04

An NADP-dependent 7 beta-hydroxysteroid dehydrogenase was purified 11.5-fold over the activity in crude cell extracts prepared from Peptostreptococcus productus strain b-52, by using Sephadex G-200 and DEAE-cellulose column chromatography. 7 beta-Dehydrogenation was the sole transformation of bile acids catalyzed by the partially purified enzyme. The enzyme preparation (spec. act. 2.781 IU per mg protein) had an optimum pH of 9.8. Lineweaver-Burk plots showed a Michaelis constant (Km) value of 0.05 mM for 3 alpha, 7 beta-dihydroxy-5 beta-cholanoic acid whereas higher values were obtained with 3 alpha,7 beta-dihydroxy-5 beta-cholanoyl glycine (0.20 mM), and 3 alpha,7 beta-dihydroxy-5 beta-cholanoyl taurine (0.26 mM). NADP but not NAD could function as an electron acceptor, and had a Km value of 0.30 mM. A molecular weight of 64000 was determined by SDS-polyacrylamide gel electrophoresis. The addition of 0.4 mM of either bile acid to the growth medium suppressed not only cell growth, but also the enzyme yield.

Differential effect of blood collection tubes on total free fatty acids (FFA) and total triiodothyronine (TT3) concentration: a model for studying interference from tube constituents.

PubMed

Bowen, Raffick A R; Vu, Chi; Remaley, Alan T; Hortin, Glen L; Csako, Gyorgy

2007-03-01

Besides total triiodothyronine (TT3), total free fatty acids (FFA) concentrations were higher with serum separator tube (SST) than Vacuette tubes. The effects of surfactant, rubber stopper, and separator gel from various tubes were investigated on FFA, beta-hydroxybutyrate (beta-HB), and TT3 with 8 different tube types in blood specimens of apparently healthy volunteers. Compared to Vacuette tubes, serum FFA and TT3 concentrations were significantly higher in SST than glass tubes. Reformulated SST eliminated the increase in TT3 but not FFA. No significant difference was observed for beta-HB concentration among tube types. Surfactant and rubber stoppers from the different tube types significantly increased TT3 but not FFA and beta-HB concentrations. Agitation of whole blood but not serum or plasma specimens with separator gel from SST, reformulated SST and plasma preparation tube (PPT) tubes compared to Vacuette tubes gave higher FFA but not beta-HB levels. Unidentified component(s) from the separator gel in SST, reformulated SST and PPT tubes cause falsely high FFA concentration. In contrast to TT3, falsely high FFA results require exposure of whole blood and not serum to tube constituent(s). The approach employed here may serve as a model for assessing interference(s) from tube constituent(s).

Seasonal patterns of plasma steroid hormones in males and females of the bearded dragon lizard, Pogona barbata.

PubMed

Amey, A P; Whittier, J M

2000-03-01

Pogona barbata is an Australian lizard that produces several large clutches of eggs between August and December (spring to early summer). Mating takes place around ovulation. The seasonal pattern of reproductive hormones in males and females of P. barbata was determined by radioimmunoassay of plasma progesterone (P), estradiol-17beta (E-17beta), corticosterone (B), and total androgen (TA). In females, P began to rise in August and was elevated from September to December. Corticosterone and TA were detectable but low and did not vary with time of year or reproductive condition. Estradiol-17beta was only detectable in a few females and exhibited no elevation with vitellogenic activity. These results suggest that B and TA are not involved in female reproduction. Estrogens may be either so low they could not be detected or they were present in a form other than estradiol-17beta. The high sensitivity of the estradiol-17beta radioimmunoassay suggests the latter. In males, TA peaked at the beginning of spring. They then declined to a minimum during November and December. However, concentrations recovered in the postbreeding activity period, January to April (summer and autumn). These patterns are consistent with the observation of maximum spermatogenic activity in spring, followed by the cessation of spermatogenesis directly after the breeding period and testicular recrudescence in February (late summer).

Hypothermia increases interleukin-6 and interleukin-10 in juvenile endotoxemic mice.

PubMed

Stewart, Corrine R; Landseadel, Jessica P; Gurka, Matthew J; Fairchild, Karen D

2010-01-01

To develop a juvenile mouse model to establish effects of in vivo hypothermia on expression of the inflammation-modulating cytokines tumor necrosis factor-alpha, interleukin-1beta, interleukin-6, and interleukin-10. Although induced hypothermia is neuroprotective in some patients, the mechanisms of protection are not well understood and concerns remain over potential detrimental effects, particularly in the setting of infection. We previously showed that in vitro hypothermia increases production of tumor necrosis factor-alpha and interleukin-1beta in lipopolysaccharide-treated monocytes. : Laboratory investigation. Research laboratory. Juvenile (4-wk) male C57BL/6 mice. : Mice were given chlorpromazine to suspend thermoregulation and lipopolysaccharide to stimulate cytokine production. Core temperature was maintained at 32 degrees C or 37 degrees C for 6 hrs by adjusting environmental temperature. In separate experiments, lipopolysaccharide-treated mice were kept in a cooling chamber without chlorpromazine treatment. Plasma and organs were collected for cytokine quantitation. Chlorpromazine-treated hypothermic mice had 2.3-fold and 1.8-fold higher plasma interleukin-6 and interleukin-10 levels at 6 hrs compared with identically treated normothermic mice (p < .05), whereas plasma tumor necrosis factor-alpha and interleukin-1beta were not significantly different at 2 hrs or 6 hrs. Liver tumor necrosis factor-alpha and interleukin-6 were significantly higher in hypothermic vs. normothermic mice, but lung and brain cytokines were not different. Lipopolysaccharide-treated mice kept in a cooling chamber without chlorpromazine treatment developed varying degrees of hypothermia with associated increases in plasma interleukin-6 and interleukin-10. A nonspecific marker of stress (plasma corticosterone) was not affected by hypothermia in lipopolysaccharide-treated mice. Further studies are necessary to determine the mechanism and physiologic consequences of augmented systemic interleukin-6 and interleukin-10 expression during induced hypothermia.

Creatine supplementation reduces plasma levels of pro-inflammatory cytokines and PGE2 after a half-ironman competition.

PubMed

Bassit, R A; Curi, R; Costa Rosa, L F B P

2008-08-01

The effect of creatine supplementation upon plasma levels of pro-inflammatory cytokines: Interleukin (IL) 1 beta and IL-6, Tumor Necrosis Factor alpha (TNFalpha), and Interferon alpha (INF alpha) and Prostaglandin E(2) (PGE(2)) after a half-ironman competition were investigated. Eleven triathletes, each with at least three years experience of participation in this sport were randomly divided between the control and experimental groups. During 5 days prior to competition, the control group (n = 6) was supplemented with carbohydrate (20 g x d(-1)) whereas the experimental group (n = 5) received creatine (20 g x d(-1)) in a double-blind trial. Blood samples were collected 48 h before and 24 and 48 h after competition and were used for the measurement of cytokines and PGE(2). Forty-eight hours prior to competition there was no difference between groups in the plasma concentrations (pg x ml(-1), mean +/- SEM) of IL-6 (7.08 +/- 0.63), TNFalpha (76.50 +/- 5.60), INF alpha (18.32 +/- 1.20), IL-1 beta (23.42 +/- 5.52), and PGE(2) (39.71 +/- 3.8). Twenty-four and 48 h after competition plasma levels of TNFalpha, INF alpha, IL-1 beta and PGE(2) were significantly increased (P < 0.05) in both groups. However, the increases in these were markedly reduced following creatine supplementation. An increase in plasma IL-6 was observed only after 24 h and, in this case, there was no difference between the two groups. Creatine supplementation before a long distance triathlon competition may reduce the inflammatory response induced by this form of strenuous of exercise.

Seminal plasma proteome of electroejaculated Bos indicus bulls.

PubMed

Rego, J P A; Crisp, J M; Moura, A A; Nouwens, A S; Li, Y; Venus, B; Corbet, N J; Corbet, D H; Burns, B M; Boe-Hansen, G B; McGowan, M R

2014-07-01

The present study describes the seminal plasma proteome of Bos indicus bulls. Fifty-six, 24-month old Australian Brahman sires were evaluated and subjected to electroejaculation. Seminal plasma proteins were separated by 2-D SDS-PAGE and identified by mass spectrometry. The percentage of progressively motile and morphologically normal sperm of the bulls were 70.4 ± 2.3 and 64 ± 3.2%, respectively. A total of 108 spots were identified in the 2-D maps, corresponding to 46 proteins. Binder of sperm proteins accounted for 55.8% of all spots detected in the maps and spermadhesins comprised the second most abundant constituents. Other proteins of the Bos indicus seminal plasma include clusterin, albumin, transferrin, metalloproteinase inhibitor 2, osteopontin, epididymal secretory protein E1, apolipoprotein A-1, heat shock 70 kDa protein, glutathione peroxidase 3, cathelicidins, alpha-enolase, tripeptidyl-peptidase 1, zinc-alpha-2-glycoprotein, plasma serine protease inhibitor, beta 2-microglobulin, proteasome subunit beta type-4, actin, cathepsins, nucleobinding-1, protein S100-A9, hemoglobin subunit alpha, cadherin-1, angiogenin-1, fibrinogen alpha and beta chain, ephirin-A1, protein DJ-1, serpin A3-7, alpha-2-macroglobulin, annexin A1, complement factor B, polymeric immunoglobulin receptor, seminal ribonuclease, ribonuclease-4, prostaglandin-H2 d-isomerase, platelet-activating factor acetylhydrolase, and phosphoglycerate kinase 1. In conclusion, this work uniquely portrays the Bos indicus seminal fluid proteome, based on samples from a large set of animals representing the Brahman cattle of the tropical Northern Australia. Based on putative biochemical attributes, seminal proteins act during sperm maturation, protection, capacitation and fertilization. Copyright © 2014. Published by Elsevier B.V.

High internal inductance for steady-state operation in ITER and a reactor

DOE PAGES

Ferron, John R.; Holcomb, Christopher T.; Luce, Timothy C.; ...

2015-06-26

Increased confinement and ideal stability limits at relatively high values of the internal inductance (more » $${{\\ell}_{i}}$$ ) have enabled an attractive scenario for steady-state tokamak operation to be demonstrated in DIII-D. Normalized plasma pressure in the range appropriate for a reactor has been achieved in high elongation and triangularity double-null divertor discharges with $${{\\beta}_{\\text{N}}}\\approx 5$$ at $${{\\ell}_{i}}\\approx 1.3$$ , near the ideal $n=1$ kink stability limit calculated without the effect of a stabilizing vacuum vessel wall, with the ideal-wall limit still higher at $${{\\beta}_{\\text{N}}}>5.5$$ . Confinement is above the H-mode level with $${{H}_{98\\left(\\text{y},2\\right)}}\\approx 1.8$$ . At $${{q}_{95}}\\approx 7.5$$ , the current is overdriven, with bootstrap current fraction $${{f}_{\\text{BS}}}\\approx 0.8$$ , noninductive current fraction $${{f}_{\\text{NI}}}>1$$ and negative surface voltage. For ITER (which has a single-null divertor shape), operation at $${{\\ell}_{i}}\\approx 1$$ is a promising option with $${{f}_{\\text{BS}}}\\approx 0.5$$ and the remaining current driven externally near the axis where the electron cyclotron current drive efficiency is high. This scenario has been tested in the ITER shape in DIII-D at $${{q}_{95}}=4.8$$ , so far reaching $${{f}_{\\text{NI}}}=0.7$$ and $${{f}_{\\text{BS}}}=0.4$$ at $${{\\beta}_{\\text{N}}}\\approx 3.5$$ with performance appropriate for the ITER Q=5 mission, $${{H}_{89}}{{\\beta}_{\\text{N}}}/q_{95}^{2}\\approx 0.3$$ . Modeling studies explored how increased current drive power for DIII-D could be applied to maintain a stationary, fully noninductive high $${{\\ell}_{i}}$$ discharge. Lastly, stable solutions in the double-null shape are found without the vacuum vessel wall at $${{\\beta}_{\\text{N}}}=4$$ , $${{\\ell}_{i}}=1.07$$ and $${{f}_{\\text{BS}}}=0.5$$ , and at $${{\\beta}_{\\text{N}}}=5$$ with the vacuum vessel wall.« less

NeuroD1 A45T and PAX4 R121W polymorphisms are associated with plasma glucose level of repaglinide monotherapy in Chinese patients with type 2 diabetes

PubMed Central

Gong, Zhi-Cheng; Huang, Qiong; Dai, Xing-Ping; Lei, Guang-Hua; Lu, Hong-Bin; Yin, Ji-Ye; Xu, Xiao-Jing; Qu, Jian; Pei, Qi; Dong, Min; Zhou, Bo-Ting; Shen, Jie; Zhou, Gan; Zhou, Hong-Hao; Liu, Zhao-Qian

2012-01-01

AIMS We aimed to determine whether NeuroD1/BETA2 and PAX4 polymorphisms were associated with the therapeutic efficacy of repaglinide in Chinese type 2 diabetes mellitus (T2DM) patients. METHODS Three hundred and sixty-eight T2DM patients and 132 healthy control subjects were genotyped by restriction fragment length polymorphism. Forty-three patients with various genotypes were randomly selected to undergo 8 weeks of repaglinide treatment (3 mg day−1). Fasting plasma glucose, postprandial plasma glucose, glycated haemoglobin, fasting and postprandial serum insulin (FINS, PINS), homeostasis model assessment for insulin resistance, serum triglyceride, total cholesterol, low-density lipoprotein-cholesterol and high-density lipoprotein-cholesterol were determined before and after repaglinide treatment. RESULTS The allelic frequency of NeuroD1/BETA2 T45 was higher in T2DM patients than in the control subjects [13.45 vs. 6.82%, P < 0.01, odds ratios = 2.342 (1.365, 4.019), P= 0.002]. Type 2 diabetes mellitus patients with the mutated allele of NeuroD1/BETA2 A45T polymorphism showed higher FINS (13.46 ± 12.57 vs. 10.04 ± 7.09 mU l−1, P < 0.05) (11.67, 14.83 vs. 8.38, 11.37) and PINS (52.11 ± 40.93 vs. 68.66 ± 43.87 mU l−1, P < 0.05) (44.89, 58.35 vs. 55.35, 88.87) than individuals with the T allele. The PAX4 R121W R allele carriers had higher PINS (52.11 ± 40.93 vs. 68.66 ± 43.87 mU l−1, P < 0.05) (44.89, 58.35 vs. 55.35, 88.87) than subjects with the W allele. After repaglinide treatment, patients with the T allele of NeuroD1/BETA2 A45T polymorphisms had attenuated efficacy on fasting plasma glucose (−2.79 ± 2.14 vs.−0.99 ± 1.80 mmol l−1, P < 0.01) (−3.53, −1.84 vs.−1.99, −0.13) and postprandial plasma glucose (−6.71 ± 5.90 vs.−2.54 ± 3.39 mmol l−1, P < 0.01) (−9.28, −4.62 vs.−4.34, −0.84). Patients with the RR genotype of PAX4 R121W showed better efficacy with respect to the level of postprandial plasma glucose than R/W genotypes (−6.53 ± 6.52 vs.−2.95 ± 1.17 mmol l−1, P < 0.05) (−8.20, −4.89 vs.−3.92, −1.20). CONCLUSIONS The NeuroD1/BETA2 and PAX4 polymorphisms were substantially associated with plasma glucose level after repaglinide monotherapy. PMID:22296034

NeuroD1 A45T and PAX4 R121W polymorphisms are associated with plasma glucose level of repaglinide monotherapy in Chinese patients with type 2 diabetes.

PubMed

Gong, Zhi-Cheng; Huang, Qiong; Dai, Xing-Ping; Lei, Guang-Hua; Lu, Hong-Bin; Yin, Ji-Ye; Xu, Xiao-Jing; Qu, Jian; Pei, Qi; Dong, Min; Zhou, Bo-Ting; Shen, Jie; Zhou, Gan; Zhou, Hong-Hao; Liu, Zhao-Qian

2012-09-01

We aimed to determine whether NeuroD1/BETA2 and PAX4 polymorphisms were associated with the therapeutic efficacy of repaglinide in Chinese type 2 diabetes mellitus (T2DM) patients. Three hundred and sixty-eight T2DM patients and 132 healthy control subjects were genotyped by restriction fragment length polymorphism. Forty-three patients with various genotypes were randomly selected to undergo 8 weeks of repaglinide treatment (3 mg day(-1)). Fasting plasma glucose, postprandial plasma glucose, glycated haemoglobin, fasting and postprandial serum insulin (FINS, PINS), homeostasis model assessment for insulin resistance, serum triglyceride, total cholesterol, low-density lipoprotein-cholesterol and high-density lipoprotein-cholesterol were determined before and after repaglinide treatment. The allelic frequency of NeuroD1/BETA2 T45 was higher in T2DM patients than in the control subjects [13.45 vs. 6.82%, P < 0.01, odds ratios = 2.342 (1.365, 4.019), P= 0.002]. Type 2 diabetes mellitus patients with the mutated allele of NeuroD1/BETA2 A45T polymorphism showed higher FINS (13.46 ± 12.57 vs. 10.04 ± 7.09 mU l(-1) , P < 0.05) (11.67, 14.83 vs. 8.38, 11.37) and PINS (52.11 ± 40.93 vs. 68.66 ± 43.87 mU l(-1), P < 0.05) (44.89, 58.35 vs. 55.35, 88.87) than individuals with the T allele. The PAX4 R121W R allele carriers had higher PINS (52.11 ± 40.93 vs. 68.66 ± 43.87 mU l(-1), P < 0.05) (44.89, 58.35 vs. 55.35, 88.87) than subjects with the W allele. After repaglinide treatment, patients with the T allele of NeuroD1/BETA2 A45T polymorphisms had attenuated efficacy on fasting plasma glucose (-2.79 ± 2.14 vs.-0.99 ± 1.80 mmol l(-1), P < 0.01) (-3.53, -1.84 vs.-1.99, -0.13) and postprandial plasma glucose (-6.71 ± 5.90 vs.-2.54 ± 3.39 mmol l(-1), P < 0.01) (-9.28, -4.62 vs.-4.34, -0.84). Patients with the RR genotype of PAX4 R121W showed better efficacy with respect to the level of postprandial plasma glucose than R/W genotypes (-6.53 ± 6.52 vs.-2.95 ± 1.17 mmol l(-1), P < 0.05) (-8.20, -4.89 vs.-3.92, -1.20). The NeuroD1/BETA2 and PAX4 polymorphisms were substantially associated with plasma glucose level after repaglinide monotherapy. © 2012 The Authors. British Journal of Clinical Pharmacology © 2012 The British Pharmacological Society.

High frequency fishbone driven by passing energetic ions in tokamak plasmas

DOE PAGES

Wang, Feng; Yu, L. M.; Fu, G. Y.; ...

2017-03-22

High frequency fishbone instability driven by passing energetic ions was first reported in the Princeton beta experiment with tangential neutral-beam-injection (Heidbrink et al 1986 Phys. Rev. Lett. 57 835–8). It could play an important role for ITER-like burning plasmas, where α particles are mostly passing particles. In this work, a generalized energetic ion distribution function and finite drift orbit width effect are considered to improve the theoretical model for passing particle driving fishbone instability. For purely passing energetic ions with zero drift orbit width, the kinetic energymore » $$\\delta {{W}_{k}}$$ is derived analytically. The derived analytic expression is more accurate as compared to the result of previous work. For a generalized energetic ion distribution function, the fishbone dispersion relation is derived and is solved numerically. As a result, numerical results show that broad and off-axis beam density profiles can significantly increase the beam ion beta threshold $${{\\beta}_{c}}$$ for instability and decrease mode frequency.« less

Progress on the Implementation of a Neutral Beam for the Lithium Tokamak eXperiment-Beta

NASA Astrophysics Data System (ADS)

Merino, Enrique; Kozub, Thomas; Boyle, Dennis; Majeski, Richard; Kaita, Robert; Smirnov, Artem; Catalano, Ryan

2016-10-01

In the Lithium Tokamak eXperiment (LTX), good performance discharges have been achieved with reduced-recycling lithium walls. Two hydrogen neutral beams (NB) have been loaned to the LTX project by Tri-Alpha Energy, Inc. To further improve plasma parameters, one of these neutral beams is being installed as part of an upgrade to LTX (LTX-Beta). Current ohmic input power in LTX is less than 100 kW. The NB will provide core plasma fueling with up to 700 kW of injected power. Requirements for accommodating the NB include the addition of injection and beam-dump ports on the vessel, and their designs have been finalized. Progress has also been made on the NB power supplies, including the preparation of a new room to accommodate them. A description of these activities and the status of other improvements to LTX for LTX-Beta will be presented. Work supported by US DOE contracts DE-AC02- 09CH11466 and DE-AC05- 00OR22725.

Increased beta-adrenergic responsiveness induced by 14 days exposure to simulated microgravity

NASA Technical Reports Server (NTRS)

Convertino, V. A.; Polet, J. L.; Engelke, K. A.; Hoffler, G. W.; Lane, L. D.; Blomqvist, C. G.

1995-01-01

Increased sensitivity of end-organ responses to neuroendocrine stimuli as a result of prolonged exposure to the relative inactivity of microgravity has recently been hypothesized. This notion is based on the inverse relationship between circulating norepinephrine and beta-adrenoreceptor sensitivity. The beta-adrenoreceptor activity is reduced in individuals who have elevated plasma norepinephrine as a result of regular exposure to upright posture and physical exercise. In contrast, adrenoreceptor hypersensitivity has been reported in patients with dysautonomias in which circulating catecholamines are absent or reduced. Taken together, these studies and the observation that circulating plasma norepinephrine has been reduced during spaceflight and in groundbased simulations of microgravity prompt the suggestion that adrenoreceptor hypersensitivity may be a consequence of the adaptation to spaceflight. We conducted an experiment designed to measure cardiovascular responses to adrenoreceptor agonists in human subjects before and after prolonged exposure to 6 deg head-down tilt (HDT) to test the hypothesis that adaptation to microgravity increases adrenoreceptor responsiveness, and that this adaptation is associated with reduced levels of circulating norepinephrine.

Are we optimizing gestational diabetes treatment with glyburide? The pharmacologic basis for better clinical practice

PubMed Central

Hebert, MF; Ma, X; Naraharisetti, SB; Krudys, KM; Umans, JG; Hankins, GDV; Caritis, SN; Miodovnik, M; Mattison, DR; Unadkat, JD; Kelly, EJ; Blough, D; Cobelli, C; Ahmed, MS; Snodgrass, WR; Carr, DB; Easterling, TR; Vicini, P

2009-01-01

Glyburide’s PK and PD have not been studied in women with gestational diabetes mellitus (GDM). The objective was to assess steady-state PK of glyburide as well as insulin sensitivity, beta-cell responsivity and overall disposition indices following a mixed meal tolerance test (MMTT) in GDM (n=40), non-pregnant type 2 diabetic (T2DM) (n=26) and healthy pregnant (n=40, MMTT only) women. At equivalent doses, glyburide plasma concentrations were ~50% lower in pregnancy compared to non-pregnant women. Average glyburide umbilical cord to maternal plasma concentration ratio at the time of delivery was 0.7 ± 0.4. Insulin sensitivity was ~5-fold lower in women with GDM compared to healthy pregnancy. Despite comparable beta-cell responsivity index, average beta-cell function corrected for insulin resistance was >3.5- fold lower in women with glyburide-treated GDM than healthy pregnancy. Women with GDM that fail glyburide may benefit from alternate medication selection or dosage escalation, though fetal safety should be considered. PMID:19295505

The H,K-ATPase beta-subunit can act as a surrogate for the beta-subunit of Na,K-pumps.

PubMed

Horisberger, J D; Jaunin, P; Reuben, M A; Lasater, L S; Chow, D C; Forte, J G; Sachs, G; Rossier, B C; Geering, K

1991-10-15

Na,K-ATPase and H,K-ATPase are the only members of the P-type ATPases in which a glycosylated beta-subunit is part of the purified active enzyme. In this study, we have followed the synthesis and the posttranslational processing of the beta-subunit of H,K-ATPase (beta HK) in Xenopus oocytes injected with beta HK cRNA and have tested whether it can act as a surrogate for the beta-subunit of Na,K-ATPase (beta NaK) to support the functional expression of Na,K-pumps. In Xenopus oocytes, beta HK is processed from an Endo H-sensitive 51-kDa coreglycosylated form to an Endo H-resistant 71-kDa fully glycosylated form. Similar to beta NaK, beta HK can stabilize and increase the trypsin resistance of alpha-subunits of Na,K-ATPase (alpha NaK). Finally, expression of beta HK together with alpha NaK leads to an increased number of ouabain binding sites at the plasma membrane accompanied by an increased Rb+ uptake and Na,K-pump current. Our data suggest that beta HK, similar to beta NaK, can assemble to alpha NaK, support the structural maturation and the intracellular transport of catalytic alpha NaK, and ultimately form active alpha NaK-beta HK complexes with Na,K-pump transport properties.

High-beta, steady-state hybrid scenario on DIII-D

DOE PAGES

Petty, C. C.; Kinsey, J. E.; Holcomb, C. T.; ...

2015-12-17

Here, the potential of the hybrid scenario (first developed as an advanced inductive scenario for high fluence) as a regime for high-beta, steady-state plasmas is demonstrated on the DIII-D tokamak. These experiments show that the beneficial characteristics of hybrids, namely safety factor ≥1 with low central magnetic shear, high stability limits and excellent confinement, are maintained when strong central current drive (electron cyclotron and neutral beam) is applied to increase the calculated non-inductive fraction to ≈100% (≈50% bootstrap current). The best discharges achieve normalized beta of 3.4, IPB98(y,2) confinement factor of 1.4, surface loop voltage of 0.01 V, and nearlymore » equal electron and ion temperatures at low collisionality. A zero-dimensional physics model shows that steady-state hybrid operation with Q fus ~ 5 is feasible in FDF and ITER. The advantage of the hybrid scenario as an Advanced Tokamak regime is that the external current drive can be deposited near the plasma axis where the efficiency is high; additionally, good alignment between the current drive and plasma current profiles is not necessary as the poloidal magnetic flux pumping self-organizes the current density profile in hybrids with an m/n=3/2 tearing mode.« less

Stability of sub-Alfvenic plasma expansions

NASA Technical Reports Server (NTRS)

Huba, J. D.; Hassam, A. B.; Winske, D.

1990-01-01

A theoretical treatment of the linear stability of sub-Alfvenic plasma expansion is developed. The theory is fully kinetic and includes finite-beta effects, collisional effects, and neutral gas flow. A variety of results are obtained, and are applied to the the AMPTE magnetotail release, the NRL laser experiment, and the upcoming CRRES GTO releases.

Structural modification of serum vitamin D3-binding protein and immunosuppression in AIDS patients.

PubMed

Yamamoto, N; Naraparaju, V R; Srinivasula, S M

1995-11-01

A serum glycoprotein, vitamin D3-binding protein (Gc protein), can be converted by beta-galactosidase of stimulated B lymphocytes and sialidase of T lymphocytes to a potent macrophage-activating factor (MAF), a protein with N-acetylgalactosamine as the remaining sugar moiety. Thus, Gc protein is a precursor for MAF. Treatment of purified Gc protein with immobilized beta-galactosidase and sialidase generates an extremely high-titered MAF (GcMAF). When peripheral blood monocytes/macrophages of 46 HIV-infected patients were treated with GcMAF (100 pg/ml), the monocytes/macrophages of all patients were efficiently activated. However, the MAF precursor activity of plasma Gc protein was low in 16 (35%) of of these patients. Loss of the MAF precursor activity appeared to be due to deglycosylation of plasma Gc protein by alpha-N-acetylgalactosaminidase found in the patient blood stream. Levels of plasma alpha-N-acetylgalactosaminidase activity in individual patients had an inverse correlation with the MAF precursor activity of their plasma Gc protein. Thus, precursor activity of Gc protein and alpha-N-acetylgalactosaminidase activity in patient blood can serve as diagnostic and prognostic indices.

Electric Tokamak Results and Plans

NASA Astrophysics Data System (ADS)

Taylor, R. J.; Gauvreau, J.-L.; Gourdain, P.-A.; Kissick, M. W.; Leboeuf, J.-N.; Schmitz, L. W.

1999-11-01

Initial plasmas have been obtained in ET (R=5 m, a=1 m) at 100 G previously with plasma currents up to 100 kA. Firsts full field plasma at 2.5 kG with the possibility of electrode and RF driven H-modes are expected in August 1999. The initial goal of the Electric Tokamak, ET(See Web Site for more details.), is to "drift lock" the thermal ions to the magnetic surfaces by rapid poloidal rotation ω_pol > ω_bounce. The required radial electric field is Er = Vi × B/A. ET physics is an outcome of the TTF effort of the last decade with a "unity beta vision" added to it by Cowley(S. C. Cowley, P. K. Kaw, R. S. Kelly, R. M. Kulsrud, \\underlinePhys. fluids B) 3 (1991) 2066. Classical heat transport is expected at 2 keV temperatures if rotation and beta can be combined, leading to the realization of an omnigeneous magnetic confinement zone(D. Palumbo, \\underlineNuovo Cimento) 53B (1967) 507.. The plasma startup experience and the scientific program plan will be discussed.

Increased plasma fibrinopeptide A levels during attacks induced by hyperventilation in patients with coronary vasospastic angina.

PubMed

Oshima, S; Ogawa, H; Yasue, H; Okumura, K; Matsuyama, K; Miyagi, H

1989-07-01

Plasma fibrinopeptide A levels, beta-thromboglobulin levels and platelet factor 4 levels were estimated by enzyme-linked immunosorbent assay before and after hyperventilation in 12 patients with coronary vasospastic angina and in 12 control subjects matched for age and gender. In all 12 study patients, anginal attacks accompanied by electrocardiographic (ECG) changes (ST elevation in 11 patients and ST depression in 1 patient) were induced by hyperventilation. Coronary angiography was performed on 11 of the 12 patients, and coronary artery spasm with the same ECG changes was induced by intracoronary injection of acetylcholine in all 11. The plasma fibrinopeptide A levels increased significantly from 2.0 +/- 0.4 to 10.0 +/- 2.4 ng/ml during the attack (p less than 0.001) in the study patients, but remained unchanged before and after hyperventilation in the control subjects. The plasma levels of beta-thromboglobulin and platelet factor 4 remained unchanged after hyperventilation in both groups. Our data indicate that coronary artery spasm may induce thrombin generation and trigger thrombus formation in the coronary artery.

Compatibility of lithium plasma-facing surfaces with high edge temperatures in the Lithium Tokamak Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Majeski, R.; Bell, R. E.; Boyle, D. P.

We measured high edge electron temperatures (200 eV or greater) at the wall-limited plasma boundary in the Lithium Tokamak Experiment (LTX). Flat electron temperature profiles are a long-predicted consequence of low recycling boundary conditions. Plasma density in the outer scrape-off layer is very low, 2-3 x 10(17) m(-3), consistent with a low recycling metallic lithium boundary. In spite of the high edge temperature, the core impurity content is low. Z(eff) is estimated to be similar to 1.2, with a very modest contribution (< 0.1) from lithium. Experiments are transient. Gas puffing is used to increase the plasma density. After gasmore » injection stops, the discharge density is allowed to drop, and the edge is pumped by the low recycling lithium wall. An upgrade to LTX-LTX-beta, which includes a 35A, 20 kV neutral beam injector (on loan to LTX from Tri-Alpha Energy) to provide core fueling to maintain constant density, as well as auxiliary heating, is underway. LTX-beta is briefly described.« less

Compatibility of lithium plasma-facing surfaces with high edge temperatures in the Lithium Tokamak Experiment

DOE PAGES

Majeski, R.; Bell, R. E.; Boyle, D. P.; ...

2017-03-20

We measured high edge electron temperatures (200 eV or greater) at the wall-limited plasma boundary in the Lithium Tokamak Experiment (LTX). Flat electron temperature profiles are a long-predicted consequence of low recycling boundary conditions. Plasma density in the outer scrape-off layer is very low, 2-3 x 10(17) m(-3), consistent with a low recycling metallic lithium boundary. In spite of the high edge temperature, the core impurity content is low. Z(eff) is estimated to be similar to 1.2, with a very modest contribution (< 0.1) from lithium. Experiments are transient. Gas puffing is used to increase the plasma density. After gasmore » injection stops, the discharge density is allowed to drop, and the edge is pumped by the low recycling lithium wall. An upgrade to LTX-LTX-beta, which includes a 35A, 20 kV neutral beam injector (on loan to LTX from Tri-Alpha Energy) to provide core fueling to maintain constant density, as well as auxiliary heating, is underway. LTX-beta is briefly described.« less

Critical analysis of the discrepancy between V(beta) and V(ss) for drugs exhibiting different two-compartment disposition profiles.

PubMed

Sobol, Eyal; Bialer, Meir

2005-03-01

It is well known that in the two-compartment open body model the values of apparent volume of distribution (V(beta)) and volume of distribution at steady state (V(ss)) are never identical. There are at least two conditions when V(beta) significantly overestimates V(ss). The first is when most of a drug is eliminated relatively rapidly but a small fraction of the dose persists and gives rise to an extremely long half-life. The second is when a drug is rapidly cleared from the central compartment with a short half-life. The primary purpose of the current paper was to investigate how different two-compartment disposition profiles affect the magnitude of difference between V(beta) and V(ss). Novel equations have been developed that relate the V(beta)/V(ss) ratio to f1 (fraction of drug elimination associated with the distributive phase) and to beta/alpha (ratio of the exponential coefficients). This paper demonstrates mathematically that an increasing value of f1 is associated with a greater divergence between V(beta) and V(ss). A similar relationship was also found for the divergence between the terminal half-life (t(1/2beta)) and the mean residence time (MRT). An increase in the beta/alpha ratio results in a substantial decrease of this discrepancy and provides a maximal possible value, or an upper limit to the V(beta)/V(ss) ratio. The newly derived equations along with their graphical presentation may serve as an excellent predictive tool for checking the accuracy of the experimentally obtained values of V(beta) and V(ss). Copyright 2004 John Wiley & Sons, Ltd.

Blocking of beta-2 adrenergic receptors hastens recovery from hypoglycemia-associated social withdrawal.

PubMed

Park, Min Jung; Guest, Christopher B; Barnes, Meredith B; Martin, Jonathan; Ahmad, Uzma; York, Jason M; Freund, Gregory G

2008-11-01

Hypoglycemia is associated with a variety of adverse behaviors including fatigue, confusion and social withdrawal. While these clinical symptoms are well characterized, the mechanism of their cause is not understood. Here we investigated how insulin-induced hypoglycemia causes social withdrawal. Male 8-12-week-old C57BL/6J mice were injected intraperitoneally (IP) with or without and/or insulin, norepinephrine (NE) and epinephrine (Epi), terbutaline and butoxamine with subsequent measurement of blood glucose, social withdrawal and plasma catecholamines. Insulin generated (0.75h post-injection) significant hypoglycemia with blood glucose nadirs of 64+/-4 and 48+/-5mg/dl for 0.8 and 1.2units/kg of insulin, respectively. Insulin (0.8 or 1.2units/kg) caused near total social withdrawal at 0.75h with full recovery not occurring until 4h (0.8units/kg) or 8h (1.2units/kg) post-insulin injection. Insulin also caused a marked elevation in plasma catecholamines. Basal 12h fasting NE and Epi were 287+/-38 and 350+/-47pg/ml, respectively. Insulin at 0.8units/kg increased plasma NE and Epi to 994+/-73 and 1842+/-473pg/ml, respectively. Administration of exogenous NE or Epi caused social withdrawal similar in magnitude to insulin. Importantly, administration of the beta-2 adrenergic receptor agonist terbutaline also caused social withdrawal while administration of the beta-2 adrenergic receptor antagonist butoxamine blocked NE-induced social withdrawal. Finally, butoxamine blocked insulin-induced social withdrawal. These data demonstrate that hypoglycemia-associated social withdrawal is dependent on catecholamines via a beta-2 receptor-mediated pathway.

Cell surface expression of beta 2-microglobulin (beta 2m) correlates with stages of differentiation in B cell tumours.

PubMed Central

Jones, R A; Scott, C S; Norfolk, D R; Stark, A N; Child, J A

1987-01-01

Cell surface beta 2-microglobulin (beta 2m) densities of malignant B cells were determined by enzyme immunoassay in 97 cases of immunologically defined lymphoproliferative disease. Absolute beta 2m densities were found to depend on disease category with the lowest levels found on cells from chronic lymphocytic leukaemia (mean = 5.6 ng/10(6) cells, n = 27); atypical chronic lymphocytic leukaemia (mean = 5.9 ng/10(6) cells, n = 8); and prolymphocytoid chronic lymphocytic leukaemia variant (mean = 6.0 ng/10(6) cells, n = 16). beta 2m densities for B non-Hodgkin's lymphoma (n = 14) and B prolymphocytic leukaemia (n = 17) cases were 8.1 and 10.0 ng/10(6) cells, respectively, and the highest densities were found on cells from "late-B cell" tumours (mean = 14.3 ng/10(6) cells). Plasma cells from cases of Ig secreting tumours expressed unexpectedly low beta 2m densities (mean = 9.3 ng/10(6) cells; n = 6). PMID:3108331

Phosphatidylinositol 5-phosphate 4-kinase type II beta is required for vitamin D receptor-dependent E-cadherin expression in SW480 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kouchi, Zen, E-mail: zkouchi@toyaku.ac.jp; Fujiwara, Yuki; Yamaguchi, Hideki

2011-05-20

Highlights: {yields} We analyzed Phosphatidylinositol 5-phosphate kinase II{beta} (PIPKII{beta}) function in cancer. {yields} PIPKII{beta} is required for vitamin D receptor-mediated E-cadherin upregulation in SW480. {yields} PIPKII{beta} suppresses cellular motility through E-cadherin induction in SW480 cells. {yields} Nuclear PIP{sub 2} but not plasma membrane-localized PIP{sub 2} mediates E-cadherin upregulation. -- Abstract: Numerous epidemiological data indicate that vitamin D receptor (VDR) signaling induced by its ligand or active metabolite 1{alpha},25-dihydroxyvitamin D{sub 3} (1{alpha},25(OH){sub 2}D{sub 3}) has anti-cancer activity in several colon cancers. 1{alpha},25(OH){sub 2}D{sub 3} induces the epithelial differentiation of SW480 colon cancer cells expressing VDR (SW480-ADH) by upregulating E-cadherin expression; however,more » its precise mechanism remains unknown. We found that phosphatidylinositol-5-phosphate 4-kinase type II beta (PIPKII{beta}) but not PIPKII{alpha} is required for VDR-mediated E-cadherin induction in SW480-ADH cells. The syntenin-2 postsynaptic density protein/disc large/zona occludens (PDZ) domain and pleckstrin homology domain of phospholipase C-delta1 (PLC{delta}1 PHD) possess high affinity for phosphatidylinositol-4,5-bisphosphate (PI(4,5)P{sub 2}) mainly localized to the nucleus and plasma membrane, respectively. The expression of syntenin-2 PDZ but not PLC{delta}1 PHD inhibited 1{alpha},25(OH){sub 2}D{sub 3}-induced E-cadherin upregulation, suggesting that nuclear PI(4,5)P{sub 2} production mediates E-cadherin expression through PIPKII{beta} in a VDR-dependent manner. PIPKII{beta} is also involved in the suppression of the cell motility induced by 1{alpha},25(OH){sub 2}D{sub 3}. These results indicate that PIPKII{beta}-mediated PI(4,5)P{sub 2} signaling is important for E-cadherin upregulation and inhibition of cellular motility induced by VDR activation.« less

Regulation of follitropin-sensitive adenylate cyclase by stimulatory and inhibitory forms of the guanine nucleotide regulatory protein in immature rat Sertoli cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, G.P.

1987-01-01

Studies have been designed to examine the role of guanine nucleotides in mediating FSH-sensitive adenylate cyclase activity in Sertoli cell plasma membranes. Analysis of ({sup 3}H)GDP binding to plasma membranes suggested a single high affinity site with a K{sub d} = 0.24 uM. Competition studies indicated that GTP{sub {gamma}}S was 7-fold more potent than GDP{sub {beta}}S. Bound GDP could be released by FSH in the presence of GTP{sub {gamma}}S, but not by FSH alone. Adenylate cyclase activity was enhanced 5-fold by FSH in the presence of GTP. Addition of GDP{sub {beta}}S to the activated enzyme (FSH plus GTP) resulted inmore » a time-dependent decay to basal activity within 20 sec. GDP{sub {beta}}S competitively inhibited GTP{sub {gamma}}S-stimulated adenylate cyclase activity with a K{sub i} = 0.18 uM. Adenylate cyclase activity was also demonstrated to be sensitive to the nucleotide bound state. In the presence of FSH, only the GTP{sub {gamma}}S-bound form persisted even if GDP{sub {beta}}S previously occupied all available binding sites. Two membrane proteins, M{sub r} = 43,000 and 48,000, were ADP{centered dot}ribosylated using cholera toxin and labeling was enhanced 2 to 4-fold by GTP{sub {gamma}}S but not by GDP{sub {beta}}S. The M{sub r} = 43,000 and 48,000 proteins represented variant forms of G{sub S}. A single protein of M{sub r} = 40,000 (G{sub i}) was ADP-ribosylated by pertussis toxin in vitro. GTP inhibited forskolin-stimulated adenylate cyclase activity with an IC{sub 50} = 0.1 uM. The adenosine analog, N{sup 6}{centered dot}phenylisopropyl adenosine enhanced GTP inhibition of forskolin-stimulated adenylate cyclase activity by an additional 15%. GTP-dependent inhibition of forskolin-sensitive adenylate cyclase activity was abolished in membranes prepared from Sertoli cells treated in culture with pertussis toxin.« less

Waves and Instabilities in Steady-State High-Beta Plasmas

DTIC Science & Technology

1976-07-01

us working on magnetospheric related problems. Several groups are now constructing identical devices including Y. Nishida of Utsunomiya University...and other satellites operate in the magnetospheric plasma environment at the geosynchronous orbit (%6.6 earth radii). Arc- related deterioration of the...carefully 16 - 3diagnosed device produces a plasma of density n 3 x 10 cm and temperature Te = Ti W 1.6eV. (3) Heat Flow Measurements in a Laser-Heated

Immune alterations in male and female mice after 2-deoxy-D-glucose administration

NASA Technical Reports Server (NTRS)

Dreau, D.; Morton, D. S.; Foster, M.; Swiggett, J. P.; Sonnenfeld, G.

1997-01-01

Administration of 2-deoxy-D-glucose (2-DG) induces acute cellular glucoprivation. In the current study, we examined differences in immune parameters after 2-DG administration in both sexes. Male and female BDF1 mice were injected three times, 48 h apart, either with a saline solution (control group) or with 2-DG in saline (500 mg/kg). Two hours after the last injection, blood and spleens were collected. Plasma levels of interleukin-1beta, and interferon-gamma levels were measured. Additionally, the levels of the specific leukocyte antigens CD3, CD4, CD8, T cell receptor (TCR) alpha/beta, I-Ad, and H-2Ld/H-2Db were evaluated by flow cytometry on both blood and spleen cells. The blastogenic response of leukocytes from both tissues to mitogens was assessed. Levels of glucose, corticosterone, testosterone, progesterone, 17beta-estradiol, follicle-stimulating hormone, and luteinizing hormone were also determined. Increases in the percentage of cells bearing TCR alpha/beta and I-Ad in the blood and H-2Ld/H-2Db in the spleen were observed in the 2-DG-treated group for both sexes. In contrast, higher corticosterone and IL-1beta plasma concentrations, as well as higher percentages of splenocytes bearing TCR alpha/beta and I-Ad, and lower mitogen-induced proliferation of mature T splenocytes (79%) were observed in female but not in male mice injected with 2-DG compared with those injected with saline (p < 0.05). Taken together, these results suggest that female mice are more sensitive than male mice to immune alterations induced by 2-DG administration.

Effect of carvedilol and nebivolol on oxidative stress-related parameters and endothelial function in patients with essential hypertension.

PubMed

Zepeda, Ramiro J; Castillo, Rodrigo; Rodrigo, Ramón; Prieto, Juan C; Aramburu, Ivonne; Brugere, Solange; Galdames, Katia; Noriega, Viviana; Miranda, Hugo F

2012-11-01

Oxidative stress and endothelial dysfunction have been associated with essential hypertension (EH) mechanisms. The purpose of this study was to evaluate the effect of carvedilol and nebivolol on the oxidative stress-related parameters and endothelial function in patients with EH. The studied population included 57 patients, either sex, between 30 and 75 years of age, with mild-to-moderate EH complications. Participants were randomized to receive either carvedilol (12.5 mg) (n = 23) or nebivolol (5 mg) (n = 21) for 12 weeks. Measurements included; 24-hr ambulatory blood pressure (BP), flow-mediated dilatation, levels of nitric oxide estimated as nitrite - a nitric oxide metabolite ( NO₂) - in plasma, and oxidative stress-related parameters in plasma and erythrocyte. EH patients who were treated with nebivolol or carvedilol showed systolic BP reductions of 17.4 and 19.9 mmHg, respectively, compared with baseline values (p < 0.01). Diastolic BP was reduced by 13.7 and 12.8 mmHg after the treatment with ebivolol and carvedilol, respectively (p < 0.01) (fig. 2B). Nebivolol and carvedilol showed 7.3% and 8.1% higher endothelium-dependent dilatation in relation to baseline values (p < 0.05). Ferric-reducing ability of plasma (FRAP) and reduced glutathione/oxidized glutathione (GSSH) ratio showed 31.5% and 29.6% higher levels in the carvedilol group compared with basal values; however, nebivolol-treated patients did not show significant differences after treatment. On the other hand, the NO₂ plasma concentration was not modified by the administration of carvedilol. However, nebivolol enhanced these levels in 62.1% after the treatment. In conclusion, this study demonstrated the antihypertensive effect of both beta-blockers. However, carvedilol could mediate these effects by an increase in antioxidant capacity and nebivolol through the raise in NO₂ concentration. Further studies are needed to determine the molecular mechanism of these effects. © 2012 The Authors Basic & Clinical Pharmacology & Toxicology © 2012 Nordic Pharmacological Society.

Development of high poloidal beta, steady-state scenario with ITER-like tungsten divertor on EAST

NASA Astrophysics Data System (ADS)

Garofalo, A. M.; Gong, X. Z.; Qian, J.; Chen, J.; Li, G.; Li, K.; Li, M. H.; Zhai, X.; Bonoli, P.; Brower, D.; Cao, L.; Cui, L.; Ding, S.; Ding, W. X.; Guo, W.; Holcomb, C.; Huang, J.; Hyatt, A.; Lanctot, M.; Lao, L. L.; Liu, H.; Lyu, B.; McClenaghan, J.; Peysson, Y.; Ren, Q.; Shiraiwa, S.; Solomon, W.; Zang, Q.; Wan, B.

2017-07-01

Recent experiments on EAST have achieved the first long pulse H-mode (61 s) with zero loop voltage and an ITER-like tungsten divertor, and have demonstrated access to broad plasma current profiles by increasing the density in fully-noninductive lower hybrid current-driven discharges. These long pulse discharges reach wall thermal and particle balance, exhibit stationary good confinement (H 98y2 ~ 1.1) with low core electron transport, and are only possible with optimal active cooling of the tungsten armors. In separate experiments, the electron density was systematically varied in order to study its effect on the deposition profile of the external lower hybrid current drive (LHCD), while keeping the plasma in fully-noninductive conditions and with divertor strike points on the tungsten divertor. A broadening of the current profile is found, as indicated by lower values of the internal inductance at higher density. A broad current profile is attractive because, among other reasons, it enables internal transport barriers at large minor radius, leading to improved confinement as shown in companion DIII-D experiments. These experiments strengthen the physics basis for achieving high performance, steady state discharges in future burning plasmas.

US-Japan bumpy torus workshop. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1985-01-01

A US-Japan ELMO Bumpy Torus Workshop was held on November 1 and 2, 1985 in Encinitas, California. The workshop focused on recent results from the Nagoya Bumpy Torus, EBT-1/S, and the proposed EBS program. The major results presented at the Workshop included extensive theoretical analyses of diamagnetic well formation by hot-electron rings in SM-1, a comprehensive review of recent experiments in NBT, and divertor concepts for EBS. Ikegami and Fujiwara summarized work on ring- and core-plasma properties, including conditions for stable ring operation, measurements of ring beta and the scaling of stored energy with heating power. Fujiwara reported a numbermore » of exciting results on ambipolar potential control in NBT. The successful outcome of ICRF experiments using twelve antennas was particularly striking. In operating regimes characterized by positive ambipolar potentials, the plasma density reached values in excess of 10/sup 13/cm/sup -3/ with ion temperatures in the 200 to 400 eV range. The plasma potential decayed with a time constant approach 0.1 sec after the ICRF pulse ended. These results appeared to be similar to predictions made over the past several years of greatly improved particle confinement in the positive ambipolar potential state.« less

Innovations in compact stellarator coil design

NASA Astrophysics Data System (ADS)

Pomphrey, N.; Berry, L.; Boozer, A.; Brooks, A.; Hatcher, R. E.; Hirshman, S. P.; Ku, L.-P.; Miner, W. H.; Mynick, H. E.; Reiersen, W.; Strickler, D. J.; Valanju, P. M.

2001-03-01

Experimental devices for the study of the physics of high beta (β gtrsim 4%), low aspect ratio (A lesssim 4.5) stellarator plasmas require coils that will produce plasmas satisfying a set of physics goals, provide experimental flexibility and be practical to construct. In the course of designing a flexible coil set for the National Compact Stellarator Experiment, several innovations have been made that may be useful in future stellarator design efforts. These include: the use of singular value decomposition methods for obtaining families of smooth current potentials on distant coil winding surfaces from which low current density solutions may be identified; the use of a control matrix method for identifying which few of the many detailed elements of a stellarator boundary must be targeted if a coil set is to provide fields to control the essential physics of the plasma; the use of a genetic algorithm for choosing an optimal set of discrete coils from a continuum of potential contours; the evaluation of alternate coil topologies for balancing the trade-off between physics objectives and engineering constraints; the development of a new coil optimization code for designing modular coils and the identification of a `natural' basis for describing current sheet distributions.

Development of high poloidal beta, steady-state scenario with ITER-like tungsten divertor on EAST

DOE PAGES

Garofalo, Andrea M.; Gong, X. Z.; Qian, J.; ...

2017-06-07

Recent experiments on EAST have achieved the first long pulse H-mode (61 s) with zero loop voltage and an ITER-like tungsten divertor, and have demonstrated access to broad plasma current profiles by increasing the density in fully-noninductive lower hybrid current-driven discharges. These long pulse discharges reach wall thermal and particle balance, exhibit stationary good confinement (H 98y2~1.1) with low core electron transport, and are only possible with optimal active cooling of the tungsten armors. In separate experiments, the electron density was systematically varied in order to study its effect on the deposition profile of the external lower hybrid current drivemore » (LHCD), while keeping the plasma in fully-noninductive conditions and with divertor strike points on the tungsten divertor. A broadening of the current profile is found, as indicated by lower values of the internal inductance at higher density. A broad current profile is attractive because, among other reasons, it enables internal transport barriers at large minor radius, leading to improved confinement as shown in companion DIII-D experiments. These experiments strengthen the physics basis for achieving high performance, steady state discharges in future burning plasmas.« less

Metabolic effects of low cortisol during exercise in humans.

PubMed

Del Corral, P; Howley, E T; Hartsell, M; Ashraf, M; Younger, M S

1998-03-01

This study examined the physiological effect of reduced plasma cortisol (C) during prolonged exercise in humans. The effects of normal C (NC) were compared with metyrapone-induced low C (LC) on plasma substrate availability and the respiratory exchange ratio during 2 h of exercise at approximately 60% peak O2 consumption in nine subjects. The C responses were compared with preexercise (Pre) levels and with a rest day (Con). At rest, C was attenuated by approximately 70% for LC compared with NC. At rest, plasma glucose, lactate, glycerol, beta-hydroxybutyrate, alanine, branched-chain amino acids, insulin, glucagon, growth hormone, epinephrine, and norepinephrine were similar under LC and NC (P > 0.05). During exercise under NC, plasma C increased compared with Pre, whereas it remained unchanged during LC. During NC, plasma C was elevated at 90 min (compared with Con) and at 120 min (compared with Con and Pre). During exercise, plasma glucose decreased to the same extent and lactate was similar under both conditions, whereas plasma glycerol, beta-hydroxybutyrate, alanine, and branched-chain amino acids were higher (P < 0.01) under NC. Plasma insulin declined (P = 0.01) to a greater extent under LC, whereas growth hormone, epinephrine, and norepinephrine tended to be higher (0.05

Time-dependent Mechanisms in Beta-cell Glucose Sensing

PubMed Central

Vagn Korsgaard, Thomas

2006-01-01

The relation between plasma glucose and insulin release from pancreatic beta-cells is not stationary in the sense that a given glucose concentration leads to a specific rate of insulin secretion. A number of time-dependent mechanisms appear to exist that modify insulin release both on a short and a longer time scale. Typically, two phases are described. The first phase, lasting up to 10 min, is a pulse of insulin release in response to fast changes in glucose concentration. The second phase is a more steady increase of insulin release over minutes to hours, if the elevated glucose concentration is sustained. The paper describes the glucose sensing mechanism via the complex dynamics of the key enzyme glucokinase, which controls the first step in glucose metabolism: phosphorylation of glucose to glucose-6-phosphate. Three time-dependent phenomena (mechanisms) are described. The fastest, corresponding to the first phase, is a delayed negative feedback regulating the glucokinase activity. Due to the delay, a rapid glucose increase will cause a burst of activity in the glucose sensing system, before the glucokinase is down-regulated. The second mechanism corresponds to the translocation of glucokinase from an inactive to an active form. As the translocation is controlled by the product(s) of the glucokinase reaction rather than by the substrate glucose, this mechanism gives a positive, but saturable, feedback. Finally, the release of the insulin granules is assumed to be enhanced by previous glucose exposure, giving a so-called glucose memory to the beta-cells. The effect depends on the insulin release of the cells, and this mechanism constitutes a second positive, saturable feedback system. Taken together, the three phenomena describe most of the glucose sensing behaviour of the beta-cells. The results indicate that the insulin release is not a precise function of the plasma glucose concentration. It rather looks as if the beta-cells just increase the insulin production, until the plasma glucose has returned to normal. This type of integral control has the advantage that the precise glucose sensitivity of the beta-cells is not important for normal glucose homeostasis. PMID:19669468

Strikingly higher interleukin (IL)-1alpha, IL-1beta and soluble interleukin-1 receptor antagonist (sIL-1RA) but similar IL-2, sIL-2R, IL-3, IL-4, IL-6, sIL-6R, IL-10, tumour necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta and interferon IFN-gamma urine levels in healthy females compared to healthy males: protection against urinary tract injury?

PubMed

Sadeghi, M; Daniel, V; Naujokat, C; Weimer, R; Opelz, G

2005-11-01

The aim of this prospective study was to examine gender-related differences of cytokines in the plasma and urine of healthy individuals that might provide a clue concerning the lower rate of chronic renal diseases in females. Soluble interleukin-1 receptor antagonist (sIL-1RA), interleukin (IL)-1alpha, IL-1beta, IL-2, sIL-2R, IL-3, IL-4, IL-6, sIL-6R, IL-10, tumor necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta(2) and interferon (IFN)-gamma were determined using standard enzyme-linked immunosorbent assay (ELISA). Cytokine levels were determined in simultaneously obtained plasma and urine samples of 18 male and 28 female healthy members of our laboratory staff. Urine cytokine levels were studied three times at 1-month intervals. All individuals had a negative urine nitrite test and showed no symptoms of urinary tract infection (UTI). Plasma levels of all studied cytokines were similar in males and females (P = n.s.). However, females had significantly higher urine IL-1alpha (P < 0.0001; P < 0.0001; P < 0.0001) and sIL-1RA (P = 0.0001; P = 0.0003; P = 0.0002) than males at three and higher IL-1beta at one of the three investigations (P = 0.098; P = 0.003; P = 0.073). Urine levels of the other cytokines were similar in males and females. Higher urine levels of IL-1alpha, IL-1beta and sIL-1RA in females may result from stimulation of cells in the urinary tract. Increased sIL-1RA might block T lymphocyte activation. The elevated cytokines may play a role in the protection of the female urinary tract from certain renal diseases, such as pyelonephritis and other inflammatory and sclerotic kidney diseases.

Evidence for the absence of cerebral glucose-6-phosphatase activity in glycogen storage disease type I (Von Gierke's disease)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phelps, M.E.; Mazziotta, J.C.; Hawkins, R.A.

1981-01-01

Glycogen storage disease type I (GSD-I) is characterized by a functional deficit in glucose-6-phosphatase that normally hydrolyzes glucose-6-PO/sub 4/ to glucose. This enzyme is primarily found in liver, kidney, and muscle but it is also present in brain, where it appears to participate in the regulation of cerebral tissue glucose. Since most neurological symptoms in GSD-I patients involve systemic hypoglycemia, previous reports have not examined possible deficiencies in phosphatase activity in the brain. Positron computed tomography, F-18-labeled 2-fluorodeoxyglucose (FDG) and a tracer kinetic model for FDG were used to measure the cortical plasma/tissue forward and reverse transport, phosphorylation and dephosphorylationmore » rate constants, tissue/plasma concentration gradient, tissue concentration turnover rate for this competitive analog of glucose, and the cortical metabolic rates for glucose. Studies were carried out in age-matched normals (N = 13) and a single GSD-I patient. The dephosphorylation rate constant in the GSD-I patient was about one tenth the normal value indicating a low level of cerebral phosphatase activity. The other measured parameters were within normal limits except for the rate of glucose phosphorylation which reflected a cortical glucose metabolic rate one half the normal value. Since glucose transport and tissue glucose concentration was normal, the reduced cortical glucose metabolism probably results from the use of alternative substrates (..beta..-hydroxybutyrate and acetoacetate) which are consistently elevated in the plasma of GSD-I patients.« less

Action of an antioxidant complex on the antioxidant power of saliva.

PubMed

Cornelli, U; Belcaro, G; Nardi, G M; Cesarone, M R; Dugall, M; Hosoi, M; Grossi, M G; Ippolito, E; Ledda, A; Ruffini, I

2010-06-01

Based on the results of the soluble antioxidants test (SAT), we have produced a combination of oral antioxidants aimed at increasing the antioxidant power of saliva. Several antioxidants are included in this product (Vit E, beta-carotene, Vit A, Vit C, polyphenols, cathechins, ellagic acid, anthocyanins, coenzyme Q10 and pyridoxine in association with Se, Zn, L-cysteine). The aim of this registry study was to evaluate the efficacy of these antioxidants in saliva, plasma and urines. MF Odontovis, an antioxidant complex, was administered to healthy subjects in the evening for one week with a final administration in the morning. Plasma, urine and saliva showed an increase in antioxidant power following both the evening administration and the final morning administration. The antioxidant action appeared to be present even at night when salival secretion is lower. Plasma SAT levels (SATs) in the morning following evening treatment were increased by 21% in comparison with controls. Morning administration increased levels up to 34% when measured 4 hours after treatment. Comparable increases were observed in saliva (SATs and morning values were +44 %; +58% two hours after morning administration and +28 % after 4 hours). In urine the evening administration caused an increase in antioxidant power (+6%). This study indicated that antioxidant levels can be increased with specific nutritional supplement. The clinical value of an increased antioxidant power in biological fluids, particularly in saliva, may be relevant for future trials of prevention and treatment.

The costo-uterine muscle of the rat contains a homogeneous population of beta-adrenoceptors.

PubMed Central

Hartley, M. L.; Pennefather, J. N.

1985-01-01

The effects of two selective beta-adrenoceptor antagonists on the inhibitory responses to some sympathomimetic amines of electrically-stimulated preparations of costo-uterine muscle, taken from virgin rats, have been examined quantitatively. pA2 values for the antagonist, atenolol (beta 1-selective) and ICI 118,551 (beta 2-selective) were obtained using as agonists, fenoterol (beta 2-selective agonist) and noradrenaline (alpha- and beta-adrenoceptor agonist, beta 1-selective); and in addition, with ICI 118,551 only, isoprenaline (beta-agonist, non-selective) and adrenaline (alpha- and beta-adrenoceptor agonist, beta 2-selective). Catecholamine uptake mechanisms and alpha-adrenoceptors were not blocked in any of these experiments. Atenolol competitively antagonized the effects of fenoterol and noradrenaline to a similar extent, the pA2 values being 5.4 and 5.7, respectively. ICI 118,551 competitively antagonized the effects of fenoterol, isoprenaline, adrenaline and noradrenaline to a similar extent; pA2 values ranged from 8.7 with noradrenaline to 9.1 with isoprenaline. These results extend our previous observations which indicated that the adrenoceptors mediating inhibition of electrically-evoked contractions of costo-uterine muscle of the virgin rat are homogeneous and of the beta 2-subtype. The potency of the beta 1-selective agonist RO 363 in producing inhibition of electrically-evoked contractions of this tissue was also examined. RO 363 was 200 times less potent than isoprenaline but was a full agonist. This indicates that there is efficient coupling between beta 2-adrenoceptor activation and tissue response in this non-innervated preparation. PMID:2858239

Preventive effects of heregulin-beta1 on macrophage foam cell formation and atherosclerosis.

PubMed

Xu, Gang; Watanabe, Takuya; Iso, Yoshitaka; Koba, Shinji; Sakai, Tetsuo; Nagashima, Masaharu; Arita, Shigeko; Hongo, Shigeki; Ota, Hidekazu; Kobayashi, Youichi; Miyazaki, Akira; Hirano, Tsutomu

2009-08-28

Human heregulins, neuregulin-1 type I polypeptides that activate proliferation, differentiation, and survival of glial cells, neurons, and myocytes, are expressed in macrophage foam cells within human coronary atherosclerotic lesions. Macrophage foam cell formation, characterized by cholesterol ester accumulation, is modulated by scavenger receptor class A (SR-A), acyl-coenzyme A:cholesterol acyltransferase (ACAT)1, and ATP-binding cassette transporter (ABC)A1. The present study clarified the roles of heregulins in macrophage foam cell formation and atherosclerosis. Plasma heregulin-beta(1) levels were significantly decreased in 31 patients with acute coronary syndrome and 33 patients with effort angina pectoris compared with 34 patients with mild hypertension and 40 healthy volunteers (1.3+/-0.3, 2.0+/-0.4 versus 7.6+/-1.4, 8.2+/-1.2 ng/mL; P<0.01). Among all patients with acute coronary syndrome and effort angina pectoris, plasma heregulin-beta(1) levels were further decreased in accordance with the severity of coronary artery lesions. Expression of heregulin-beta(1) was observed at trace levels in intracoronary atherothrombosis obtained by aspiration thrombectomy from acute coronary syndrome patients. Heregulin-beta(1), but not heregulin-alpha, significantly reduced acetylated low-density lipoprotein-induced cholesterol ester accumulation in primary cultured human monocyte-derived macrophages by reducing SR-A and ACAT1 expression and by increasing ABCA1 expression at both mRNA and protein levels. Heregulin-beta(1) significantly decreased endocytic uptake of [(125)I]acetylated low-density lipoprotein and ACAT activity, and increased cholesterol efflux to apolipoprotein (Apo)A-I from human macrophages. Chronic infusion of heregulin-beta(1) into ApoE(-/-) mice significantly suppressed the development of atherosclerotic lesions. This study provided the first evidence that heregulin-beta(1) inhibits atherogenesis and suppresses macrophage foam cell formation via SR-A and ACAT1 downregulation and ABCA1 upregulation.

Characterization of a beta-glucanase produced by Rhizopus microsporus var. microsporus, and its potential for application in the brewing industry.

PubMed

Celestino, Klecius R Silveira; Cunha, Ricardo B; Felix, Carlos R

2006-12-05

In the barley malting process, partial hydrolysis of beta-glucans begins with seed germination. However, the endogenous 1,3-1,4-beta-glucanases are heat inactivated, and the remaining high molecular weight beta-glucans may cause severe problems such as increased brewer mash viscosity and turbidity. Increased viscosity impairs pumping and filtration, resulting in lower efficiency, reduced yields of extracts, and lower filtration rates, as well as the appearance of gelatinous precipitates in the finished beer. Therefore, the use of exogenous beta-glucanases to reduce the beta-glucans already present in the malt barley is highly desirable. The zygomycete microfungus Rhizopus microsporus var. microsporus secreted substantial amounts of beta-glucanase in liquid culture medium containing 0.5% chitin. An active protein was isolated by gel filtration and ion exchange chromatographies of the beta-glucanase activity-containing culture supernatant. This isolated protein hydrolyzed 1,3-1,4-beta-glucan (barley beta-glucan), but showed only residual activity against 1,3-beta-glucan (laminarin), or no activity at all against 1,4-beta-glucan (cellulose), indicating that the R. microsporus var. microsporus enzyme is a member of the EC 3.2.1.73 category. The purified protein had a molecular mass of 33.7 kDa, as determined by mass spectrometry. The optimal pH and temperature for hydrolysis of 1,3-1,4-beta-glucan were in the ranges of 4-5, and 50-60 degrees C, respectively. The Km and Vmax values for hydrolysis of beta-glucan at pH 5.0 and 50 degrees C were 22.39 mg.mL-1 and 16.46 mg.min-1, respectively. The purified enzyme was highly sensitive to Cu+2, but showed less or no sensitivity to other divalent ions, and was able to reduce both the viscosity and the filtration time of a sample of brewer mash. In comparison to the values determined for the mash treated with two commercial glucanases, the relative viscosity value for the mash treated with the 1,3-1,4-beta-glucanase produced by R. microsporus var. microsporus. was determined to be consistently lower. The zygomycete microfungus R. microsporus var. microsporus produced a 1,3-1,4-beta-D-glucan 4-glucanhydrolase (EC 3.2.1.73) which is able to hydrolyze beta-D-glucan that contains both the 1,3- and 1,4-bonds (barley beta-glucans). Its molecular mass was 33.7 kDa. Maximum activity was detected at pH values in the range of 4-5, and temperatures in the range of 50-60 degrees C. The enzyme was able to reduce both the viscosity of the brewer mash and the filtration time, indicating its potential value for the brewing industry.

Isolation and characterization of cDNA clones for human erythrocyte beta-spectrin.

PubMed Central

Prchal, J T; Morley, B J; Yoon, S H; Coetzer, T L; Palek, J; Conboy, J G; Kan, Y W

1987-01-01

Spectrin is an important structural component of the membrane skeleton that underlies and supports the erythrocyte plasma membrane. It is composed of nonidentical alpha (Mr 240,000) and beta (Mr 220,000) subunits, each of which contains multiple homologous 106-amino acid segments. We report here the isolation and characterization of a human erythroid-specific beta-spectrin cDNA clone that encodes parts of the beta-9 through beta-12 repeat segments. This cDNA was used as a hybridization probe to assign the beta-spectrin gene to human chromosome 14 and to begin molecular analysis of the gene and its mRNA transcripts. RNA transfer blot analysis showed that the reticulocyte beta-spectrin mRNA is 7.8 kilobases in length. Southern blot analysis of genomic DNA revealed the presence of restriction fragment length polymorphisms (RFLPs) within the beta-spectrin gene locus. The isolation of human spectrin cDNA probes and the identification of closely linked RFLPs will facilitate analysis of mutant spectrin genes causing congenital hemolytic anemias associated with quantitative and qualitative spectrin abnormalities. Images PMID:3478706

BETA (Bitter Electromagnet Testing Apparatus)

NASA Astrophysics Data System (ADS)

Bates, Evan M.; Birmingham, William J.; Rivera, William F.; Romero-Talamas, Carlos A.

2017-10-01

The Bitter Electromagnet Testing Apparatus (BETA) is a 1-Tesla (T) prototype of the 10-T Adjustable Long Pulse High-Field Apparatus (ALPHA). These water-cooled resistive magnets use high DC currents to produce strong uniform magnetic fields. Presented here is the successful completion of the BETA project and experimental results validating analytical magnet designing methods developed at the Dusty Plasma Laboratory (DPL). BETA's final design specifications will be highlighted which include electromagnetic, thermal and stress analyses. The magnet core design will be explained which include: Bitter Arcs, helix starters, and clamping annuli. The final version of the magnet's vessel and cooling system are also presented, as well as the electrical system of BETA, which is composed of a unique solid-state breaker circuit. Experimental results presented will show the operation of BETA at 1 T. The results are compared to both analytical design methods and finite element analysis calculations. We also explore the steady state maximums and theoretical limits of BETA's design. The completion of BETA validates the design and manufacturing techniques that will be used in the succeeding magnet, ALPHA.

Modification of the interleukin-6 response to air pollution by interleukin-6 and fibrinogen polymorphisms.

PubMed

Ljungman, Petter; Bellander, Tom; Schneider, Alexandra; Breitner, Susanne; Forastiere, Francesco; Hampel, Regina; Illig, Thomas; Jacquemin, Bénédicte; Katsouyanni, Klea; von Klot, Stephanie; Koenig, Wolfgang; Lanki, Timo; Nyberg, Fredrik; Pekkanen, Juha; Pistelli, Riccardo; Pitsavos, Christos; Rosenqvist, Mårten; Sunyer, Jordi; Peters, Annette

2009-09-01

Evidence suggests that cardiovascular effects of air pollution are mediated by inflammation and that air pollution can induce genetic expression of the interleukin-6 gene (IL6). We investigated whether IL6 and fibrinogen gene variants can affect plasma IL-6 responses to air pollution in patients with cardiovascular disease. We repeatedly determined plasma IL-6 in 955 myocardial infarction survivors from six European cities (n = 5,539). We conducted city-specific analyses using additive mixed models adjusting for patient characteristics, time trend, and weather to assess the impact of air pollutants on plasma IL-6. We pooled city-specific estimates using meta-analysis methodology. We selected three IL6 single-nucleotide polymorphisms (SNPs) and one SNP each from the fibrinogen alpha-chain gene (FGA) and beta-chain gene (FGB) for gene-environment analyses. We found the most consistent modifications for variants in IL6 rs2069832 and FBG rs1800790 after exposure to carbon monoxide (CO; 24-hr average; p-values for interaction, 0.034 and 0.019, respectively). Nitrogen dioxide effects were consistently modified, but p-values for interaction were larger (0.09 and 0.19, respectively). The strongest effects were seen 6-11 hr after exposure, when, for example, the overall effect of a 2.2% increase in IL-6 per 0.64 mg/m(3) CO was modified to a 10% (95% confidence interval, 4.6-16%) increase in IL-6 (p-value for interaction = 0.002) for minor homozygotes of FGB rs1800790. The effect of gaseous traffic-related air pollution on inflammation may be stronger in genetic subpopulations with ischemic heart disease. This information could offer an opportunity to identify postinfarction patients who would benefit more than others from a cleaner environment and antiinflammatory treatment.

Comparison of confinement in resistive-shell reversed-field pinch devices with two different magnetic shell penetration times

NASA Astrophysics Data System (ADS)

Gravestijn, R. M.; Drake, J. R.; Hedqvist, A.; Rachlew, E.

2004-01-01

A loop voltage is required to sustain the reversed-field pinch (RFP) equilibrium. The configuration is characterized by redistribution of magnetic helicity but with the condition that the total helicity is maintained constant. The magnetic field shell penetration time, tgrs, has a critical role in the stability and performance of the RFP. Confinement in the EXTRAP device has been studied with two values of tgrs, first (EXTRAP-T2) with tgrs of the order of the typical relaxation cycle timescale and then (EXTRAP-T2R) with tgrs much longer than the relaxation cycle timescale, but still much shorter than the pulse length. Plasma parameters show significant improvements in confinement in EXTRAP-T2R. The typical loop voltage required to sustain comparable electron poloidal beta values is a factor of 3 lower in the EXTRAP-T2R device. The improvement is attributed to reduced magnetic turbulence.

High β produced by neutral beam injection in the START (Small Tight Aspect Ratio Tokamak) spherical tokamak

NASA Astrophysics Data System (ADS)

Sykes, Alan

1997-05-01

The world's first high-power auxiliary heating experiments in a tight aspect ratio (or spherical) tokamak have been performed on the Small Tight Aspect Ratio Tokomak (START) device [Sykes et al., Nucl. Fusion 32, 694 (1992)] at Culham Laboratory, using the 40 keV, 0.5 MW Neutral Beam Injector loaned by the Oak Ridge National Laboratory. Injection has been mainly of hydrogen into hydrogen or deuterium target plasmas, with a one-day campaign to explore D→D operation. In each case injection provides a combination of higher density operation and effective heating of both ions and electrons. The highest β values achieved to date in START are volume average βT˜11.5% and central beta βO˜50%. Already high, these values are expected to increase further with the use of higher beam power.

Dissociation of lipotoxicity and glucotoxicity in a mouse model of obesity associated diabetes: role of forkhead box O1 (FOXO1) in glucose-induced beta cell failure.

PubMed

Kluth, O; Mirhashemi, F; Scherneck, S; Kaiser, D; Kluge, R; Neschen, S; Joost, H-G; Schürmann, A

2011-03-01

Carbohydrate-free diet prevents hyperglycaemia and beta cell destruction in the New Zealand Obese (NZO) mouse model. Here we have used a sequential dietary regimen to dissociate the effects of obesity and hyperglycaemia on beta cell function and integrity, and to study glucose-induced alterations of key transcription factors over 16 days. Mice were rendered obese by feeding a carbohydrate-free diet for 18 weeks. Thereafter, a carbohydrate-containing diet was given. Plasma glucose, plasma insulin and total pancreatic insulin were determined, and forkhead box O1 protein (FOXO1) phosphorylation and the transcription factors pancreatic and duodenal homeobox 1 (PDX1), NK6 homeobox 1 protein (NKX6.1) and v-maf musculoaponeurotic fibrosarcoma oncogene family, protein A (avian) (MAFA) were monitored by immunohistochemistry for 16 days. Dietary carbohydrates produced a rapid and continuous increase in plasma glucose in NZO mice between day 2 and 16 after the dietary challenge. Hyperglycaemia caused a dramatic dephosphorylation of FOXO1 at day 2, followed by a progressive depletion of insulin stores. The loss of beta cells was triggered by apoptosis (detectable at day 8), associated with reduction of crucial transcription factors (PDX1, NKX6.1 and MAFA). Incubation of isolated islets from carbohydrate-restricted NZO mice or MIN6 cells with palmitate and glucose for 48 h resulted in a dephosphorylation of FOXO1 and thymoma viral proto-oncogene 1 (AKT) without changing the protein levels of both proteins. The dietary regimen dissociates the effects of obesity (lipotoxicity) from those of hyperglycaemia (glucotoxicity) in NZO mice. Obese NZO mice are unable to compensate for the carbohydrate challenge by increasing insulin secretion or synthesising adequate amounts of insulin. In response to the hyperglycaemia, FOXO1 is dephosphorylated, leading to reduced levels of beta cell-specific transcription factors and to apoptosis of the cells.

Identification of 17,20beta,21-trihydroxy-4-pregnen-3-one as an oocyte maturation-inducing steroid in black porgy, Acanthopagrus schlegeli.

PubMed

Yueh, Wen-Shiun; Thomas, Peter; Chang, Ching-Fong

2005-02-01

The identity of the maturation-inducing steroid (MIS) in black porgy, Acanthopagrus schlegeli, a marine protandrous teleost, is unknown. Previous studies demonstrated that two teleost MISs, the progestins 17,20beta,21-trihydroxy-4-pregnen-3-one (20beta-S) and 17,20beta-dihydroxy-4-pregnen-3-one (DHP) can induce maturation of black porgy oocytes in vitro. The purpose of the present study was to identify the major progestin produced during oocyte maturation (OM) in black porgy and investigate whether its secretion increases during this process. Females were injected twice with a LHRH analog to induce OM. Ovarian follicles undergoing OM were incubated in vitro with tritiated [3H]pregnenolone precursor and the tritiated products were extracted, purified, and identified by HPLC, TLC, acetylation, and recrystallization. Significant amounts of tritiated products were biosynthesized from [3H]pregnenolone that co-migrated with 20beta-S but not with DHP on HPLC and TLC. Similar TLC profiles were obtained with the tritiated products isolated from the HPLC/TLC 20beta-S fraction and standard 20beta-S after the acetylation reaction. The identity of the tritiated products as 20beta-S was confirmed by recrystallization. 20beta-S had a slightly higher potency than DHP in the inducing in vitro final oocyte maturation. Plasma 20beta-S concentrations increased significantly during the oocyte maturation after injection with a LHRH analog. The present data suggest that 20beta-S is the MIS in black porgy.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, G.F.; Marks, B.H.

This study examines the beta adrenergic receptors of the rabbit detrusor smooth muscle, employing (/sup 125/I)iodocyanopindolol (ICYP) as a ligand for the binding of beta adrenergic receptors. Saturation binding experiments on the isolated membrane fraction yielded a KD for ICYP of 14.7 pM and a maximum binding of 147.6 fmol/mg of protein. Displacement of labeled ICYP by a series of beta adrenergic agents yielded the following KD values for the combined high and low affinity binding sites: I-propranolol, 0.76 nM; ICI 118,551, 1.7 nM; zinterol, 38.0 nM; metoprolol, 3.5 microM; and practolol, 61.4 microM. When these displacement experimental results weremore » compared to KD values from other reported binding studies with ICYP for beta adrenoreceptors, both the order of potency and the KD values indicated primarily beta-2 adrenergic receptor subtypes. Computer program Scatfit analysis of the displacement curves indicated a single slope and affinity constant for all five beta adrenergic agents. Hofstee plots for zinterol, ICI 118,551 and metoprolol, however, were not linear and indicated that minor populations of beta-1 adrenoreceptors were also present as both high and low affinity binding sites could be defined. It is concluded that the primary receptor population is beta-2 and that this tissue is heterogenous with a small population of beta-1 adrenoreceptors representing approximately 13 to 23% of the total beta adrenoreceptor population.« less

Interleukin 1 beta inhibits synaptic strength and long-term potentiation in the rat CA1 hippocampus.

PubMed

Bellinger, F P; Madamba, S; Siggins, G R

1993-11-19

Cytokines such as interleukin-1 beta (IL-1 beta) are released in the nervous system following inflammation or infection. Recently, IL-1 beta was shown to enhance synaptic inhibitory mechanisms. We therefore investigated the effect of IL-1 beta superfusion on long-term potentiation (LTP), the cellular model of memory and learning, evoked in the CA1 region by tetanic stimulation of the stratum radiatum in the rat hippocampal slice. IL-1 beta (150 pM-1.5 nM) superfused 10 min before tetanic stimulation significantly reduced LTP of the slope of the population excitatory postsynaptic potential (pEPSP) and the population spike (PS) amplitude in CA1 in a concentration-dependent manner. IL-1 beta (1.5 nM) applied for 10 min 1 h before tetanus significantly inhibited LTP of the PS amplitude and pEPSP slope and reduced pEPSP and PS values before tetanus as well, although the PS returned to control values before tetanus. Heat-inactivated IL-1 beta had no effect on pre-tetanus pEPSP or PS values or the induction of LTP. These data demonstrate that IL-1 beta modulates synaptic potentials and reduces LTP. These findings have important implications for the role of IL-1 beta in neuronal disorders following infection, perhaps best exemplified by HIV-1-associated dementia.

Natural Divertor Spherical Tokamak Plasmas with bean shape and ergodic limiter

NASA Astrophysics Data System (ADS)

Ribeiro, Celso; Herrera, Julio; Chavez, Esteban; Tritz, Kevin

2013-10-01

The former spherical tokamak (ST) MEDUSA (Madison EDUcation Small Aspect.ratio tokamak, R < 0.14 m, a < 0.10 m, BT < 0.5T, Ip < 40 kA, 3 ms pulse) is being recommissioned in Costa Rica Institute of Technology. The main objectives of the MEDUSA-CR project are training and to clarify several issues in relevant physics for conventional and mainly STs, including beta studies in bean-shaped ST plasmas, transport, heating and current drive via Alfvén wave, and natural divertor STs with ergodic magnetic limiter. We report here improvements in the self-consistency of these equilibrium comparisons and a preliminary study of their MHD stability beta limits. VIE-ITCR, IAEA-CRP contract 17592, National Instruments of Costa Rica.

Enhancement of glucose uptake in skeletal muscle L6 cells and insulin secretion in pancreatic hamster-insulinoma-transfected cells by application of non-thermal plasma jet

NASA Astrophysics Data System (ADS)

Kumar, Naresh; Kaushik, Nagendra K.; Park, Gyungsoon; Choi, Eun H.; Uhm, Han S.

2013-11-01

Type-II diabetes Mellitus is characterized by defects in insulin action on peripheral tissues, such as skeletal muscle, adipose tissue, and liver and pancreatic beta cells. Since the skeletal muscle accounts for approximately 75% of insulin-stimulated glucose-uptake in our body, impaired insulin secretion from defected beta cell plays a major role in the afflicted glucose homoeostasis. It was shown that the intracellular reactive oxygen species and nitric oxide level was increased by non-thermal-plasma treatment in ambient air. These increased intracellular reactive species may enhance glucose uptake and insulin secretion through the activation of intracellular calcium (Ca+) and cAMP production.

Study of long term structural and functional changes in medically controlled glaucoma

PubMed Central

Pandey, Achyut N; Sujata, S

2014-01-01

AIM Prospectively analyze the long term structural and functional changes in patients of primary open angle glaucoma (POAG) receiving medical therapy (beta blockers and non beta blockers). In this study an attempt has been made to evaluate whether medical reduction of IOP prevents or delays the progression of glaucomatous visual field loss and/or optic nerve damage in patients with open angle glaucoma. METHODS Study conducted over a period of 27 months, at a tertiary eye care hospital including both eyes of 40 patients with POAG. Group 1 (20 patients, 40 eyes) received beta-blockers, and Group 2 (20 patients, 40 eyes) received non-beta-blockers. Each patient underwent intraocular pressure measurement, best corrected visual acuity, slit-lamp, fundus examination, gonioscopy, central corneal thickness, visual field assessment by Humphrey automated perimetry and retinal nerve fibre layer thickness by Stratus optical coherence tomography at baseline and at two subsequent visits. The average time interval between each visit was 10-11 months. The statistical analysis was done using one-way analysis of variance (ANOVA). Post-hoc test, using tukey' method were adopted. Probablity (P) value of 0.05 or less was considered to be statistically significant. RESULTS A total of 80 eyes of 40 patients of POAG were enrolled, 24 males, 16 females, age group 50-80 years. In both beta and non beta blocker group, reduction (improvement) in mean IOP from initial levels to the levels achieved at the 2nd and 3rd visits was statistically significant. One way ANOVA (df=2), fisher f value=11.64, P=0.000, one way ANOVA (df=3), fisher f value=35.61, P=0.000. Both mean deviation (MD) and pattern standard deviation (PSD) in both beta and non beta blockers at different visits were not statistically significant. Retinal nerve fibre layer thickness (RNFL) -only mean inferior retinal nerve fibre layer, the difference between the mean value in beta and non beta blocker groupwere statistically significant. [unpaired t test value (df=78) =2.27, P=0.03]. Side effects with beta blocker were conjunctival hyperemia (10%), burning (5%), and conjunctival hyperemia (5%) in non beta blockers. CONCLUSION Non-beta-blockers are as effective as beta-blockers in bringing about a significant lowering of intraocular pressure to the normal range, and in preventing progressive damage to the visual fields and retinal nerve fibre layer. The absence of systemic side effects and superior IOP lowering efficacy has made non beta-blockers attractive for first line therapy for the treatment of glaucoma worldwide. PMID:24634878

Study of long term structural and functional changes in medically controlled glaucoma.

PubMed

Pandey, Achyut N; Sujata, S

2014-01-01

Prospectively analyze the long term structural and functional changes in patients of primary open angle glaucoma (POAG) receiving medical therapy (beta blockers and non beta blockers). In this study an attempt has been made to evaluate whether medical reduction of IOP prevents or delays the progression of glaucomatous visual field loss and/or optic nerve damage in patients with open angle glaucoma. Study conducted over a period of 27 months, at a tertiary eye care hospital including both eyes of 40 patients with POAG. Group 1 (20 patients, 40 eyes) received beta-blockers, and Group 2 (20 patients, 40 eyes) received non-beta-blockers. Each patient underwent intraocular pressure measurement, best corrected visual acuity, slit-lamp, fundus examination, gonioscopy, central corneal thickness, visual field assessment by Humphrey automated perimetry and retinal nerve fibre layer thickness by Stratus optical coherence tomography at baseline and at two subsequent visits. The average time interval between each visit was 10-11 months. The statistical analysis was done using one-way analysis of variance (ANOVA). Post-hoc test, using tukey' method were adopted. Probablity (P) value of 0.05 or less was considered to be statistically significant. A total of 80 eyes of 40 patients of POAG were enrolled, 24 males, 16 females, age group 50-80 years. In both beta and non beta blocker group, reduction (improvement) in mean IOP from initial levels to the levels achieved at the 2nd and 3rd visits was statistically significant. One way ANOVA (df=2), fisher f value=11.64, P=0.000, one way ANOVA (df=3), fisher f value=35.61, P=0.000. Both mean deviation (MD) and pattern standard deviation (PSD) in both beta and non beta blockers at different visits were not statistically significant. Retinal nerve fibre layer thickness (RNFL) -only mean inferior retinal nerve fibre layer, the difference between the mean value in beta and non beta blocker groupwere statistically significant. [unpaired t test value (df=78) =2.27, P=0.03]. Side effects with beta blocker were conjunctival hyperemia (10%), burning (5%), and conjunctival hyperemia (5%) in non beta blockers. Non-beta-blockers are as effective as beta-blockers in bringing about a significant lowering of intraocular pressure to the normal range, and in preventing progressive damage to the visual fields and retinal nerve fibre layer. The absence of systemic side effects and superior IOP lowering efficacy has made non beta-blockers attractive for first line therapy for the treatment of glaucoma worldwide.

Plasma pentosidine levels measured by a newly developed method using ELISA in patients with chronic renal failure.

PubMed

Sanaka, Tsutomu; Funaki, Takenori; Tanaka, Toshihisa; Hoshi, Sayako; Niwayama, Jyun; Taitoh, Takashi; Nishimura, Hideki; Higuchi, Chieko

2002-05-01

The plasma pentosidine levels in patients with renal disease were measured by a simple method which was established for plasma and urinary pentosidine determinations. The method, which can be completed within a few hours, involves pretreating plasma with proteolytic enzyme (pronase) and measuring the concentration of pentosidine in the sample by ELISA using antipentosidine antibodies. The prepared antibodies showed no cross-reaction with the raw materials for pentosidine synthesis or with compounds having similar structures. SDS-PAGE indicated that the antibodies had a high purity. The reaction of the antibodies and keyhole limpet hemocyanin-pentosidine in the competitive ELISA system was inhibited by free pentosidine. Excellent standard curves for pentosidine determination were obtained. In actual measurements of clinical samples from patients, a good correlation (r = 0.9356) was obtained between the values measured by ELISA and HPLC. The plasma pentosidine level in patients with renal disease correlated significantly with plasma creatinine, urea nitrogen, beta2-microglobulin, and creatinine clearance, indicating its usefulness in evaluating the severity of renal disease. A significant elevation in plasma pentosidine levels was observed in mild renal dysfunction, whereas no significant increases in creatinine and urea nitrogen levels were detected, suggesting that the plasma pentosidine level is useful in the early diagnosis of beginning renal failure. In patients with chronic renal failure, no difference in plasma pentosidine levels was observed between diabetic nephropathy and chronic glomerulonephritis, while a significant correlation was observed with phosphatidylcholine hydroperoxide, suggesting the possibility that the plasma pentosidine level reflects injury due to oxidation. From these results, the quantitative measurement method developed by us is judged to be a superior innovation for measuring pentosidine in body fluids. The plasma pentosidine level may be useful for the early diagnosis of mild renal failure and to estimate the degree of the severity of renal diseases. Copyright 2002 S. Karger AG, Basel

Strong and weak plasma response to dietary carotenoids identified by cluster analysis and linked to beta-carotene 15,15'-monooxygenase 1 single nucleotide polymorphisms

USDA-ARS?s Scientific Manuscript database

The mechanisms as well the genetics underlying bioavailability and metabolism of carotenoids in humans remains unclear. The individual temporal response of plasma carotenoids was analyzed in adults who consumed carotenoid-containing juices on a controlled-diet study using cluster analysis. Treatmen...

Gene- and environment-dependent neuroendocrine etiogenesis of homosexuality and transsexualism.

PubMed

Dörner, G; Poppe, I; Stahl, F; Kölzsch, J; Uebelhack, R

1991-01-01

Sexual brain organization is dependent on sex hormone and neurotransmitter levels occurring during critical developmental periods. The higher the androgen levels during brain organization, caused by genetic and/or environmental factors, the higher is the biological predisposition to bi- and homosexuality or even transsexualism in females and the lower it is in males. Adrenal androgen excess, leading to heterotypical sexual orientation and/or gender role behavior in genetic females, can be caused by 21-hydroxylase deficiency, especially when associated with prenatal stress. The cortisol (F) precursor 21-deoxycortisol (21-DOF) was found to be significantly increased after ACTH stimulation in homosexual as compared to heterosexual females. 21-DOF was increased significantly before and even highly significantly after ACTH stimulation in female-to-male transsexuals. In view of these data, heterozygous and homozygous forms, respectively, of 21-hydroxylase deficiency represent a genetic predisposition to androgen-dependent development of homosexuality and transsexualism in females. Testicular androgen deficiency in prenatal life, giving rise to heterotypical sexual orientation and/or gender role behavior in genetic males, may be induced by prenatal stress and/or maternal or fetal genetic alterations. Most recently, in mothers of homosexual men--following ACTH stimulation--a significantly increased prevalence of high 21-DOF plasma values and 21-DOF/F ratios was found, which surpassed the mean + 1 SD level of heterosexual control women. In homosexual men as well--following ACTH stimulation--most of the 21-DOF plasma values and 21-DOF/F ratios also surpassed the mean + 1 SD level of heterosexual men. In only one out of 9 homosexual males, neither in his blood nor in that of his mother increased 21-DOF values and 21-DOF/F ratios were found after ACTH stimulation. In this homosexual man, however, the plasma dehydroepiandrosterone sulfate (DHEA-S) values and the DHEA-S/1000 x A (A = androstenedione) ratio were increased before and after ACTH stimulation. Furthermore, highly significantly increased basal plasma levels of dehydroepiandrosterone sulfate were found in male-to-female transsexuals as compared to normal males, suggesting partial 3 beta-ol hydroxysteroid dehydrogenase deficiency to be a predisposing factor for the development of male-to-female transsexualism.

Development of a PCR/LDR/capillary electrophoresis assay with potential for the detection of a beta-thalassemia fetal mutation in maternal plasma.

PubMed

Yi, Ping; Chen, Zhuqin; Yu, Lili; Zheng, Yingru; Liu, Guodong; Xie, Haichang; Zhou, Yuanguo; Zheng, Xiuhui; Han, Jian; Li, Li

2010-08-01

Analysis of fetal DNA in maternal plasma has recently been introduced for non-invasive prenatal diagnosis. We have now investigated the feasibility of polymerase chain reaction (PCR)/ligase detection reaction (LDR)/capillary electrophoresis for the detection of fetal point mutations, such as the beta-thalassemia mutation, IVS2 654(C --> T), in maternal plasma DNA. The sensitivity of LDR/capillary electrophoresis was examined by quantifying the mutant PCR products in the presence of a vast excess of non-mutant competitor template, a situation that mimics the detection of rare fetal mutations in the presence of excess maternal DNA. PCR/LDR/capillary electrophoresis was applied to detect the mutation, IVS2 654(C --> T), in an experimental model at different sensitivity levels and from 10 maternal plasma samples. Our results demonstrated that this approach to detect a low abundance IVS2 654(C --> T) mutation achieved a sensitivity of approximately 1:10,000. The approach was applied to maternal plasma DNA to detect the paternally inherited fetal IVS2 654(C --> T) mutation, and the results were equivalent to those obtained by PCR/reverse dot blot of amniotic fluid cell DNA. PCR/LDR/capillary electrophoresis has a very high sensitivity that can distinguish low abundance single nucleotide differences and can detect paternally inherited fetal point mutations in maternal plasma.

Pre-analytical stability of the plasma proteomes based on the storage temperature

PubMed Central

2013-01-01

Background This study examined the effect of storage temperature on the protein profile of human plasma. Plasma samples were stored for 13 days at -80°C, -20°C, +4°C and room temperature (20-25°C) prior to proteomic analysis. The proteomic comparisons were based on the differences of mean intensity values of protein spots between fresh plasma samples (named “time zero”) and plasma samples stored at different temperatures. To better understand the thermally induced biochemical changes that may affect plasma proteins during storage we identified proteins with different expressions with respect to the time zero sample. Results Using two-dimensional electrophoresis followed by MALDI-TOF MS and /or LC-MS/MS 20 protein spots representing 10 proteins were identified with significant differences in abundance when stored at different temperatures. Our results, in agreement with various authors, indicate that during storage for a short period (13 days) at four different temperatures plasma proteins were more affected by degradation processes at +4°C compared to the other temperatures analysed. However, we founded that numerous protein spots (vitamin D binding protein, alpha-1-antitrypsin, serotransferrin, apoplipoprotein A-I, apolipoprotein E, haptoglobin and complement factor B) decrease in abundance with increasing temperature up to 4°C, but at room temperature their intensity mean values are similar to those of time zero and -80°C. We hypothesize that these proteins are labile at 4°C, but at the same time they are stable at room temperature (20-25°C). Furthermore we have grouped the proteins based on their different sensitivity to the storage temperature. Spots of serum albumin, fibrinogen gamma chain and haptoglobin are more resistant to the higher temperatures tested, as they have undergone changes in abundance only at room temperature; conversely, other spots of serum albumin, fibrinogen beta chain and serotransferrin are more labile as they have undergone changes in abundance at all temperatures except at -80°C. Conclusions Although there are many studies concerning protein stability of clinical samples during storage these findings may help to provide a better understanding of the changes of proteins induced by storage temperature. PMID:23518135

A membrane-anchored E-type endo-1,4-beta-glucanase is localized on Golgi and plasma membranes of higher plants.

PubMed

Brummell, D A; Catala, C; Lashbrook, C C; Bennett, A B

1997-04-29

Endo-1,4-beta-D-glucanases (EGases, EC 3.2.1.4) are enzymes produced in bacteria, fungi, and plants that hydrolyze polysaccharides possessing a 1,4-beta-D-glucan backbone. All previously identified plant EGases are E-type endoglucanases that possess signal sequences for endoplasmic reticulum entry and are secreted to the cell wall. Here we report the characterization of a novel E-type plant EGase (tomato Cel3) with a hydrophobic transmembrane domain and structure typical of type II integral membrane proteins. The predicted protein is composed of 617 amino acids and possesses seven potential sites for N-glycosylation. Cel3 mRNA accumulates in young vegetative tissues with highest abundance during periods of rapid cell expansion, but is not hormonally regulated. Antibodies raised to a recombinant Cel3 protein specifically recognized three proteins, with apparent molecular masses of 93, 88, and 53 kDa, in tomato root microsomal membranes separated by sucrose density centrifugation. The 53-kDa protein comigrated in the gradient with plasma membrane markers, the 88-kDa protein with Golgi membrane markers, and the 93-kDa protein with markers for both Golgi and plasma membranes. EGase enzyme activity was also found in regions of the density gradient corresponding to both Golgi and plasma membranes, suggesting that Cel3 EGase resides in both membrane systems, the sites of cell wall polymer biosynthesis. The in vivo function of Cel3 is not known, but the only other known membrane-anchored EGase is present in Agrobacterium tumefaciens where it is required for cellulose biosynthesis.

Plasma Confinement in the UCLA Electric Tokamak.

NASA Astrophysics Data System (ADS)

Taylor, Robert J.

2001-10-01

The main goal of the newly constructed large Electric Tokamak (R = 5 m, a = 1 m, BT < 0.25 T) is to access an omnigeneous, unity beta(S.C. Cowley, P.K. Kaw, R.S. Kelly, R.M. Kulsrud, Phys. fluids B 3 (1991) 2066.) plasma regime. The design goal was to achieve good confinement at low magnetic fields, consistent with the high beta goal. To keep the program cost down, we adopted the use of ICRF as the primary heating source. Consequently, antenna surfaces covering 1/2 of the surface of the tokamak has been prepared for heating and current drive. Very clean hydrogenic plasmas have been achieved with loop voltage below 0.7 volt and densities 3 times above the Murakami limit, n(0) > 8 x 10^12 cm-3 when there is no MHD activity. The electron temperature, derived from the plasma conductivity is > 250 eV with a central electron energy confinement time > 350 msec in ohmic conditions. The sawteeth period is 50 msec. Edge plasma rotation is induced by plasma biasing via electron injection in an analogous manner to that seen in CCT(R.J. Taylor, M.L. Brown, B.D. Fried, H. Grote, J.R. Liberati, G.J. Morales, P. Pribyl, D. Darrow, and M. Ono. Phys. Rev Lett. 63 2365 1989.) and the neoclassical bifurcation is close to that described by Shaing et al(K.C. Shaing and E.C. Crume, Phys. Rev. Lett. 63 2369 (1989).). In the ohmic phase the confinement tends to be MHD limited. The ICRF heating eliminates the MHD disturbances. Under second harmonic heating conditions, we observe an internal confinement peaking characterized by doubling of the core density and a corresponding increase in the central electron temperature. Charge exchange data, Doppler data in visible H-alpha light, and EC radiation all indicate that ICRF heating works much better than expected. The major effort is focused on increasing the power input and controlling the resulting equilibrium. This task appears to be easy since our current pulses are approaching the 3 second mark without RF heating or current drive. Our initial experience with current profile control, needed for high beta plasma equilibrium, will be also discussed.

Non-linear isotope and fast ions effects: routes for low turbulence in DT plasmas

NASA Astrophysics Data System (ADS)

Garcia, Jeronimo

2017-10-01

The isotope effect, i.e. the fact that heat and particle fluxes do not follow the expected Gyro-Bohm estimate for turbulent transport when the plasma mass is changed, is one of the main challenges in plasma theory. Of particular interest is the isotope exchange between the fusion of deuterium (DD) and deuterium-tritium (DT) nuclei as there are no clear indications of what kind of transport difference can be expected in burning plasmas. The GENE code is therefore used for computing DD vs DT linear and nonlinear microturbulence characteristics in the core plasma region of a previously ITER hybrid scenario at high beta obtained in the framework of simplified integrated modelling. Scans on common turbulence related quantitates as external ExB flow shear, Parallel Velocity Gradient (PVG), plasma beta, colisionality or the number of ion species have been performed. Additionally, the role of energetic particles, known to reduce Ion Temperature Gradient (ITG) turbulence has been also addressed. It is obtained that the ITER operational point will be close to threshold and in these conditions turbulence is dominated by ITG modes. A purely weak non-linear isotope effect, absent in linear scans, can be found when separately adding moderate ExB flow shear or electromagnetic effects, whereas collisionality just modulates the intensity. The isotope effect, on the other hand, becomes very strong in conditions with simultaneously moderate ExB flow shear, beta and low q profile with significant reductions of ion heat transport from DD to DT. By analyzing the radial structure of the two point electrostatic potential correlation function it has been found that the inherent Gyro-Bohm scaling for plasma microturbulence, which increases the radial correlation length at short scales form DD to DT, is counteracted by the concomitant appearance of a complex nonlinear multiscale space interaction involving external ExB flow shear, zonal flow activity, magnetic geometry and electromagnetic effects. The number of ion species and the fast ion population is also found to play a role in this non-linear process whereas a symmetry breaking between D and T, with systematic reduced heat and particle transport for T, is always obtained.

Magnetic control of magnetohydrodynamic instabilities in tokamaks

DOE PAGES

Strait, Edward J.

2014-11-24

Externally applied, non-axisymmetric magnetic fields form the basis of several relatively simple and direct methods to control magnetohydrodynamic (MHD) instabilities in a tokamak, and most present and planned tokamaks now include a set of non-axisymmetric control coils for application of fields with low toroidal mode numbers. Non-axisymmetric applied fields are routinely used to compensate small asymmetries ( δB/B ~ 10 -3 to 10 -4) of the nominally axisymmetric field, which otherwise can lead to instabilities through braking of plasma rotation and through direct stimulus of tearing modes or kink modes. This compensation may be feedback-controlled, based on the magnetic responsemore » of the plasma to the external fields. Non-axisymmetric fields are used for direct magnetic stabilization of the resistive wall mode — a kink instability with a growth rate slow enough that feedback control is practical. Saturated magnetic islands are also manipulated directly with non-axisymmetric fields, in order to unlock them from the wall and spin them to aid stabilization, or position them for suppression by localized current drive. Several recent scientific advances form the foundation of these developments in the control of instabilities. Most fundamental is the understanding that stable kink modes play a crucial role in the coupling of non-axisymmetric fields to the plasma, determining which field configurations couple most strongly, how the coupling depends on plasma conditions, and whether external asymmetries are amplified by the plasma. A major advance for the physics of high-beta plasmas ( β = plasma pressure/magnetic field pressure) has been the understanding that drift-kinetic resonances can stabilize the resistive wall mode at pressures well above the ideal-MHD stability limit, but also that such discharges can be very sensitive to external asymmetries. The common physics of stable kink modes has brought significant unification to the topics of static error fields at low beta and resistive wall modes at high beta. Furthermore, these and other scientific advances, and their application to control of MHD instabilities, will be reviewed with emphasis on the most recent results and their applicability to ITER.« less

Taurine transport across hepatocyte plasma membranes: analysis in isolated rat liver sinusoidal plasma membrane vesicles.

PubMed

Inoue, M; Arias, I M

1988-07-01

To elucidate the mechanism of taurine transport across the hepatic plasma membranes, rat liver sinusoidal plasma membrane vesicles were isolated and the transport process was analyzed. In the presence of a sodium gradient across the membranes (vesicle inside less than vesicle outside), an overshooting uptake of taurine occurred. In the presence of other ion gradients (K+, Li+, and choline+), taurine uptake was very small and no such overshoot was observed. Sodium-dependent uptake of taurine occurred into an osmotically active intravesicular space. Taurine uptake was stimulated by preloading vesicles with unlabeled taurine (transstimulation) in the presence of NaCl, but not in the presence of KCl. Sodium-dependent transport followed saturation kinetics with respect to taurine concentration; double-reciprocal plots of uptake versus taurine concentration gave a straight line from which an apparent Km value of 0.38 mM and Vmax of 0.27 nmol/20 s x mg of protein were obtained. Valinomycin-induced K+-diffusion potential failed to enhance the rate of taurine uptake, suggesting that taurine transport does not depend on membrane potential. Taurine transport was inhibited by structurally related omega-amino acids, such as beta-alanine and gamma-aminobutyric acid, but not by glycine, epsilon-aminocaproic acid, or other alpha-amino acids, such as L-alanine. These results suggest that Na+-dependent uptake of taurine might occur across the hepatic sinusoidal plasma membranes via a transport system that is specific for omega-amino acids having 2-3 carbon chain length.

Measurement of scrape-off-layer current dynamics during MHD activity and disruptions in HBT-EP

NASA Astrophysics Data System (ADS)

Levesque, J. P.; Brooks, J. W.; Abler, M. C.; Bialek, J.; Byrne, P. J.; Hansen, C. J.; Hughes, P. E.; Mauel, M. E.; Navratil, G. A.; Rhodes, D. J.

2017-08-01

We report scrape-off layer (SOL) current measurements during magnetohydrodynamic (MHD) mode activity, resonant magnetic perturbations (RMPs), and disruptions in the High Beta Tokamak—Extended Pulse (HBT-EP) device. Currents are measured via segmented plasma current Rogowski coils, jumpers running toroidally between otherwise-isolated vessel sections, and a grounded electrode in the scrape-off layer. These currents strongly depend on the plasma’s major radius, and amplitude and phase of non-axisymmetric field components. SOL currents connecting through the vessel are seen to reach  ∼0.2{--}0.5 % of the plasma current during typical kink activity and RMPs. Plasma current asymmetries and scrape-off-layer currents generated during disruptions, which are commonly called halo currents, reach  ∼4 % of I p. Asymmetric toroidal currents between vessel sections rotate at tens of kHz through most of the current quench, then symmetrize once I p reaches  ∼30 % of its pre-disruptive value. Toroidal jumper currents oscillate between co- and counter-I p, with co-I p being dominant on average during disruptions. A relative increase in local plasma current measured by a segmented I p Rogowski coil correlates with counter-I p current in the nearest toroidal jumper. Measurements are interpreted in the context of two models that produce contrary predictions for the toroidal vessel current polarity during disruptions. Plasma current asymmetry measurements are consistent with both models, and SOL currents scale with plasma displacement toward the vessel wall. The design of an upcoming SOL current diagnostic and control upgrade is also briefly presented.

The quiescent H-mode regime for high performance edge localized mode-stable operation in future burning plasmas [The quiescent H-mode regime for high performance ELM-stable operation in future burning plasmas

DOE PAGES

Garofalo, Andrea M.; Burrell, Keith H.; Eldon, David; ...

2015-05-26

For the first time, DIII-D experiments have achieved stationary quiescent H-mode (QH-mode) operation for many energy confinement times at simultaneous ITER-relevant values of beta, confinement, and safety factor, in an ITER similar shape. QH-mode provides excellent energy confinement, even at very low plasma rotation, while operating without edge localized modes (ELMs) and with strong impurity transport via the benign edge harmonic oscillation (EHO). By tailoring the plasma shape to improve the edge stability, the QH-mode operating space has also been extended to densities exceeding 80% of the Greenwald limit, overcoming the long-standing low-density limit of QH-mode operation. In the theory,more » the density range over which the plasma encounters the kink-peeling boundary widens as the plasma cross-section shaping is increased, thus increasing the QH-mode density threshold. Here, the DIII-D results are in excellent agreement with these predictions, and nonlinear MHD analysis of reconstructed QH-mode equilibria shows unstable low n kink-peeling modes growing to a saturated level, consistent with the theoretical picture of the EHO. Furthermore, high density operation in the QH-mode regime has opened a path to a new, previously predicted region of parameter space, named “Super H-mode” because it is characterized by very high pedestals that can be more than a factor of two above the peeling-ballooning stability limit for similar ELMing H-mode discharges at the same density.« less

Clinical observations on enzyme replacement therapy in patients with Fabry disease and the switch from agalsidase beta to agalsidase alfa.

PubMed

Lin, Hsiang-Yu; Huang, Yu-Hsiu; Liao, Hsuan-Chieh; Liu, Hao-Chuan; Hsu, Ting-Rong; Shen, Chia-I; Li, Shao-Tzu; Li, Cheng-Fang; Lee, Li-Hong; Lee, Pi-Chang; Huang, Chun-Kai; Chiang, Chuan-Chi; Lin, Shuan-Pei; Niu, Dau-Ming

2014-04-01

Fabry disease is an X-linked inherited lysosomal storage disease that can be treated with the enzymes of agalsidase beta (Fabrazyme) and agalsidase alfa (Replagal). Since June 2009, viral contamination of Genzyme's production facility has resulted in a worldwide shortage of agalsidase beta, leading to the switch to agalsidase alfa for patients with Fabry disease in Taiwan. The medical records were retrospectively reviewed for nine male patients with Fabry disease from the start of agalsidase beta treatment until the switch to agalsidase alfa for at least 1 year. After 12-112 months of enzyme replacement therapy (ERT), decreased plasma globotriaosylsphingosine (lyso-Gb3) was found in five out of seven patients, indicating improvement in disease severity. Among the six patients with available echocardiographic data at baseline and after ERT, all six experienced reductions of left ventricular mass index. Renal function, including microalbuminuria and estimated glomerular filtration rate, showed stability after ERT. Mainz Severity Score Index scores revealed that all nine patients remained stable at 12 months after switching to agalsidase alfa. ERT improved or stabilized cardiac status and stabilized renal function, while reducing plasma lyso-Gb3. ERT was well tolerated, even among the three patients who had hypersensitivity reactions. The switch of ERT from agalsidase beta to agalsidase alfa appears to be safe after 1 year of follow-up for Taiwanese patients with Fabry disease. Copyright © 2013. Published by Elsevier B.V.

Advances in the high bootstrap fraction regime on DIII-D towards the Q = 5 mission of ITER steady state

DOE PAGES

Qian, Jinping P.; Garofalo, Andrea M.; Gong, Xianzu Z.; ...

2017-03-20

Recent EAST/DIII-D joint experiments on the high poloidal betamore » $${{\\beta}_{\\text{P}}}$$ regime in DIII-D have extended operation with internal transport barriers (ITBs) and excellent energy confinement (H 98y2 ~ 1.6) to higher plasma current, for lower q 95 ≤ 7.0, and more balanced neutral beam injection (NBI) (torque injection < 2 Nm), for lower plasma rotation than previous results. Transport analysis and experimental measurements at low toroidal rotation suggest that the E × B shear effect is not key to the ITB formation in these high $${{\\beta}_{\\text{P}}}$$ discharges. Experiments and TGLF modeling show that the Shafranov shift has a key stabilizing effect on turbulence. Extrapolation of the DIII-D results using a 0D model shows that with the improved confinement, the high bootstrap fraction regime could achieve fusion gain Q = 5 in ITER at $${{\\beta}_{\\text{N}}}$$ ~ 2.9 and q 95 ~ 7. With the optimization of q(0), the required improved confinement is achievable when using 1.5D TGLF-SAT1 for transport simulations. Furthermore, results reported in this paper suggest that the DIII-D high $${{\\beta}_{\\text{P}}}$$ scenario could be a candidate for ITER steady state operation.« less

Prediction of beta-turns from amino acid sequences using the residue-coupled model.

PubMed

Guruprasad, K; Shukla, S

2003-04-01

We evaluated the prediction of beta-turns from amino acid sequences using the residue-coupled model with an enlarged representative protein data set selected from the Protein Data Bank. Our results show that the probability values derived from a data set comprising 425 protein chains yielded an overall beta-turn prediction accuracy 68.74%, compared with 94.7% reported earlier on a data set of 30 proteins using the same method. However, we noted that the overall beta-turn prediction accuracy using probability values derived from the 30-protein data set reduces to 40.74% when tested on the data set comprising 425 protein chains. In contrast, using probability values derived from the 425 data set used in this analysis, the overall beta-turn prediction accuracy yielded consistent results when tested on either the 30-protein data set (64.62%) used earlier or a more recent representative data set comprising 619 protein chains (64.66%) or on a jackknife data set comprising 476 representative protein chains (63.38%). We therefore recommend the use of probability values derived from the 425 representative protein chains data set reported here, which gives more realistic and consistent predictions of beta-turns from amino acid sequences.

11beta-Hydroxysteroid dehydrogenase Type 1: genetic polymorphisms are associated with Type 2 diabetes in Pima Indians independently of obesity and expression in adipocyte and muscle.

PubMed

Nair, S; Lee, Y H; Lindsay, R S; Walker, B R; Tataranni, P A; Bogardus, C; Baier, L J; Permana, P A

2004-06-01

The enzyme 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) modulates tissue-specific glucocorticoid concentrations by generating active cortisol. We have shown that adipose tissue 11beta-HSD1 mRNA levels were associated with adiposity and insulinaemia. Here we conducted further expression and genetic association studies in Pima Indians. The 11beta-HSD1 mRNA concentrations were measured in abdominal subcutaneous adipocytes (n=61) and skeletal muscle tissues (n=64). Single nucleotide polymorphisms in the HSD11B1 gene were genotyped in a larger group of full-blooded Pima Indians. Two representative SNPs (SNP1, n=706; SNP5, n=839) were associated with Type 2 diabetes mellitus (p=0.01), although neither SNP was associated with obesity. Among subjects with normal glucose tolerance, SNP1 (n=127) and SNP5 (n=159) were associated with insulin-mediated glucose uptake rates (p=0.03 and p=0.04), and SNP1 was further associated with fasting, 30-min, and 2-h plasma insulin concentrations (p=0.002, p=0.002 and p=0.03). Adipocyte 11beta-HSD1 mRNA concentrations were correlated positively with adiposity and insulinaemia, and were additionally negatively correlated with insulin-mediated glucose uptake rates; nevertheless, the adipocyte 11beta-HSD1 expression did not correlate with genotypes of the donors. The muscle 11beta-HSD1 mRNA concentrations did not correlate with any anthropometric or metabolic variables. We confirmed that adipocyte 11beta-HSD1 mRNA concentrations were associated with adiposity, and showed that genetic variations in the HSD11B1 gene were associated with Type 2 diabetes mellitus, plasma insulin concentrations and insulin action, independent of obesity. The variable adipose expression might not be a primary consequence of these HSD11B1 SNPs. Therefore, it is possible that the HSD11B1 gene is under tissue-specific regulation, and has tissue-specific consequences.

Exercise induced asthma and endogenous opioids.

PubMed Central

Gaillard, R C; Bachman, M; Rochat, T; Egger, D; de Haller, R; Junod, A F

1986-01-01

Concentrations of endogenous opioid peptides in the plasma are increased during exercise and these substances have been implicated in the pathogenesis of asthma induced by chloropropramide and alcohol in diabetic patients. This work was undertaken to determine whether exercise induced asthma might be mediated by endogenous opioids. Plasma beta endorphin, met-enkephalin, and adrenocorticotrophic hormone (ACTH) concentrations were measured in five asthmatic patients and five normal volunteers breathing cold air during exercise. In four of the patients the effect of an infusion of naloxone on FEV1 was also measured during exercise induced asthma. Exercise produced acute bronchoconstriction in all asthmatics, characterised by a fall in FEV1; whereas no change occurred in normal subjects. There was no difference in plasma met-enkephalin, beta endorphin, and ACTH concentration between the two groups. Infusion of naloxone neither prevented nor worsened exercise induced asthma. These data suggest that endogenous opioids probably do not play a part in the development of exercise induced asthma. PMID:2944240

Plasma lipophilic antioxidants and malondialdehyde in congestive heart failure patients: relationship to disease severity.

PubMed

Polidori, Maria Cristina; Savino, Ketty; Alunni, Gianfranco; Freddio, Michela; Senin, Umberto; Sies, Helmut; Stahl, Wilhelm; Mecocci, Patrizia

2002-01-15

Plasma levels of malondialdehyde (MDA), vitamin A, and of antioxidant micronutrients including vitamin E, lutein, zeaxanthin, beta-cryptoxanthin, lycopene, and alpha- and beta-carotene were measured in 30 patients with class II and III congestive heart failure (CHF) according to the New York Heart Association (NYHA) classification and in 55 controls. Ejection fraction was evaluated by echocardiography in all patients as a measure of the emptying capacity of the heart. Plasma levels of all measured compounds were significantly lower and MDA significantly higher in patients compared to controls (p <.001). Class II NYHA patients showed significantly lower MDA levels and significantly higher levels of vitamin A, vitamin E, lutein, and lycopene than class III patients. Ejection fraction was inversely correlated with MDA levels and directly correlated with vitamin A, vitamin E, lutein, and lycopene levels in patients. The present study supports the concept that an increased consumption of vitamin-rich fruits and vegetables might help in achieving cardiovascular health.

Persistent organohalogen contaminants in plasma from groups of humans with different occupations in Bangladesh.

PubMed

Zamir, R; Athanasiadou, M; Nahar, N; Mamun, M I R; Mosihuzzaman, M; Bergman, A

2009-01-01

The present study is aimed to assess persistent organic halogenated pollutants in humans living in Bangladesh. The results are compared to other similar studies in the region and globally. Human blood plasma were collected from groups of men and women with different occupations, i.e. being students, garment industry workers, employees at the Power Development Board (PDB), all groups in Dhaka, fishermen and fishermen wife's from Dhaka and another group from Barisal district. The plasma was analysed for hexachlorobenzene (HCB), the hexachlorocyclohexane isomers, alpha-HCH, beta-HCH, gamma-HCH and delta-HCH, the DDT group of chemicals, chlordane compounds, trans-chlordane, cis-chlordane, oxychlordane, trans-nonachlor, trans-heptachlorepoxide, methoxychlor and mirex. The most abundant contaminant, in all groups studied, p,p'-DDE is dominating, with p,p'-DDT/Sigma DDT ratios indicating recent and ongoing DDT exposure. Among the other pesticides analysed beta-HCH is the most abundant indicating the use of technical HCH products instead of Lindane (gamma-HCH). While the Sigma DDT is present in the low ppm range the beta-HCH is detected in up to approx. 400 ppb, lipid basis. The beta-HCH is most abundant in the groups of students. In contrast to the pesticides analysed very low concentrations of polychlorinated biphenyls (PCB) are present in all study groups, with e.g. CB-153 in the range of 5-30 ng g(-1) fat. The concentrations of the DDT group of chemical differ significantly between fishermen and fishermen's wives living and working in the Dhaka area versus those living and working in Barisal. Also, fishermen and their wives had significantly different concentrations of DDT compared to garment industry workers.

Postprandial lipid, glucose, insulin, and cholecystokinin responses in men fed barley pasta enriched with beta-glucan.

PubMed

Bourdon, I; Yokoyama, W; Davis, P; Hudson, C; Backus, R; Richter, D; Knuckles, B; Schneeman, B O

1999-01-01

Fiber regulates the rate and site of lipid and carbohydrate digestion and absorption and thus can modify the alimentary responses to a meal. When fiber sources containing viscous polysaccharides are included in a meal, a slower rate of carbohydrate and lipid absorption will modify the alimentary hormone and lipid responses. We investigated in 11 healthy men the response of insulin, glucose, cholecystokinin, and lipid to 2 test meals containing beta-glucan. One of the meals was high in fiber (15.7 g) and the other meal was low in fiber (5.0 g). The low-fiber meal contained pasta made with wheat flour. The high-fiber meals contained pasta prepared by replacing 40% of the wheat with 2 types of barley flour: barley naturally high in beta-glucan and the other a flour enriched in beta-glucan during processing. Plasma glucose and insulin concentrations increased significantly after all meals but the insulin response was more blunted after the barley-containing meals. The test meals were low in fat (25% of energy) but elicited an increase in plasma triacylglycerol and cholecystokinin. Cholecystokinin remained elevated for a longer time after the barley-containing meals. After the low-fiber meal, plasma cholesterol concentrations did not change significantly; however, 4 h after the barley-containing meals, the cholesterol concentration dropped below the fasting concentration and was significantly lower than that after the low-fiber meal. Carbohydrate was more slowly absorbed from the 2 high-fiber meals. Consumption of the barley-containing meals appeared to stimulate reverse cholesterol transport, which may contribute to the cholesterol-lowering ability of barley.

Three-dimensional kinetic simulations of whistler turbulence in solar wind on parallel supercomputers

NASA Astrophysics Data System (ADS)

Chang, Ouliang

The objective of this dissertation is to study the physics of whistler turbulence evolution and its role in energy transport and dissipation in the solar wind plasmas through computational and theoretical investigations. This dissertation presents the first fully three-dimensional (3D) particle-in-cell (PIC) simulations of whistler turbulence forward cascade in a homogeneous, collisionless plasma with a uniform background magnetic field B o, and the first 3D PIC simulation of whistler turbulence with both forward and inverse cascades. Such computationally demanding research is made possible through the use of massively parallel, high performance electromagnetic PIC simulations on state-of-the-art supercomputers. Simulations are carried out to study characteristic properties of whistler turbulence under variable solar wind fluctuation amplitude (epsilon e) and electron beta (betae), relative contributions to energy dissipation and electron heating in whistler turbulence from the quasilinear scenario and the intermittency scenario, and whistler turbulence preferential cascading direction and wavevector anisotropy. The 3D simulations of whistler turbulence exhibit a forward cascade of fluctuations into broadband, anisotropic, turbulent spectrum at shorter wavelengths with wavevectors preferentially quasi-perpendicular to B o. The overall electron heating yields T ∥ > T⊥ for all epsilone and betae values, indicating the primary linear wave-particle interaction is Landau damping. But linear wave-particle interactions play a minor role in shaping the wavevector spectrum, whereas nonlinear wave-wave interactions are overall stronger and faster processes, and ultimately determine the wavevector anisotropy. Simulated magnetic energy spectra as function of wavenumber show a spectral break to steeper slopes, which scales as k⊥lambda e ≃ 1 independent of betae values, where lambdae is electron inertial length, qualitatively similar to solar wind observations. Specific spectral indices from simulated wavevector energy spectra do not match the frequency spectral indices from observations due to the inapplicability of Taylor's hypothesis. In contrast, the direct comparison of simulated frequency energy spectra and solar wind observations shows a closer similarity. Electron density fluctuations power spectra also exhibit a close similarity to solar wind observations and MHD predications, both qualitatively and quantitatively. Linear damping represents an intermediate fraction of the total dissipation of whistler turbulence over a wide range of betae and epsilone. The relative importance of linear damping by comparison to nonlinear dissipation increases with increasing beta e but decreases with increasing epsilone. Correlation coefficient calculations imply that the nonlinear dissipation processes in our simulation are primarily associated with dissipation in regions of intermittent current sheet structures. The simulation results suggest that whistler fluctuations could be the substantial constituent of solar wind turbulence at higher frequencies and short wavelengths, and support the magnetosonic-whistler interpretation of the quasilinear scenario. An even larger scale 3D whistler turbulence simulation exhibits both a forward cascade to shorter wavelengths with wavevectors preferentially k⊥ > k∥, and an inverse cascade to longer wavelengths with wavevectors k ≳ k⊥. The inverse cascade process is primarily driven by the nonlinear wave-wave interaction. It is shown that the energy inverse cascade rate is similar to the energy forward cascade rate at early times although the overall energy in the two cascades is very different. The presence of inverse cascade process does not affect qualitative conclusions established from the whistler turbulence forward cascade simulations.

Decreased NT-3 plasma levels and platelet serotonin content in patients with hypochondriasis.

PubMed

Brondino, Natascia; Lanati, Niccolò; Barale, Francesco; Martinelli, Valentina; Politi, Pierluigi; Geroldi, Diego; Emanuele, Enzo

2008-11-01

Neurotrophins (NT) are a family of closely related proteins, including brain-derived neurotrophic factor, nerve growth factor, neurotrophin-3 (NT-3), and neurotrophin-4/5 (NT-4/5). NTs are deemed to regulate several aspects of neuronal survival, development, and function. Although NTs have been associated to a variety of mental disorders, the potential role of NT alterations in hypochondriasis (HC) has never been investigated. In the present study, plasma concentrations of NTs were evaluated in 23 adult patients meeting Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria for HC and 22 healthy controls. Platelet serotonin (5-HT) content was chosen as a measure of serotonergic function. Hypochondriacal symptoms were assessed using the Whiteley Index of Hypochondriasis (WIH). Plasma NT-3 level (P=.004) and platelet 5-HT (P=.008) were significantly lower in patients with HC compared with controls. Correlation analyses showed that the WIH score was significantly and inversely associated with both NT-3 values (r=-.60, P=.002) and platelet serotonin content (r=-.53, P=.009). We used a multivariate regression model to determine independent predictors of the WIH score. After allowance for potential confounders, plasma NT-3 levels remained the unique independent predictor of the WIH (beta=.003, t=-3.5, P=.003). Decreased NT-3 concentration, alongside with serotonin dysfunction, may represent a biological correlate of HC.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garofalo, Andrea M.; Burrell, Keith H.; Eldon, David

For the first time, DIII-D experiments have achieved stationary quiescent H-mode (QH-mode) operation for many energy confinement times at simultaneous ITER-relevant values of beta, confinement, and safety factor, in an ITER similar shape. QH-mode provides excellent energy confinement, even at very low plasma rotation, while operating without edge localized modes (ELMs) and with strong impurity transport via the benign edge harmonic oscillation (EHO). By tailoring the plasma shape to improve the edge stability, the QH-mode operating space has also been extended to densities exceeding 80% of the Greenwald limit, overcoming the long-standing low-density limit of QH-mode operation. In the theory,more » the density range over which the plasma encounters the kink-peeling boundary widens as the plasma cross-section shaping is increased, thus increasing the QH-mode density threshold. Here, the DIII-D results are in excellent agreement with these predictions, and nonlinear MHD analysis of reconstructed QH-mode equilibria shows unstable low n kink-peeling modes growing to a saturated level, consistent with the theoretical picture of the EHO. Furthermore, high density operation in the QH-mode regime has opened a path to a new, previously predicted region of parameter space, named “Super H-mode” because it is characterized by very high pedestals that can be more than a factor of two above the peeling-ballooning stability limit for similar ELMing H-mode discharges at the same density.« less

An acid phosphatase in the plasma membranes of human astrocytoma showing marked specificity toward phosphotyrosine protein.

PubMed

Leis, J F; Kaplan, N O

1982-11-01

The plasma membrane from the human tumor astrocytoma contains an active acid phosphatase activity based on hydrolysis of p-nitrophenyl phosphate. Other acid phosphatase substrates--beta-glycerophosphate, O-phosphorylcholine, and 5'-AMP--are not hydrolyzed significantly. The phosphatase activity is tartrate insensitive and is stimulated by Triton X-100 and EDTA. Of the three known phosphoamino acids, only free O-phosphotyrosine is hydrolyzed by the membrane phosphatase activity. Other acid phosphatases tested from potato, wheat germ, milk, and bovine prostate did not show this degree of specificity. The plasma membrane activity also dephosphorylated phosphotyrosine histone at a much greater rate than did the other acid phosphatases. pH profiles for free O-phosphotyrosine and phosphotyrosine histone showed a shift toward physiological pH, indicating possible physiological significance. Phosphotyrosine histone dephosphorylation activity was nearly 10 times greater than that seen for phosphoserine histone dephosphorylation, and Km values were much lower for phosphotyrosine histone dephosphorylation (0.5 microM vs. 10 microM). Fluoride and zinc significantly inhibited phosphoserine histone dephosphorylation. Vanadate, on the other hand, was a potent inhibitor of phosphotyrosine histone dephosphorylation (50% inhibition at 0.5 microM) but not of phosphoserine histone. ATP stimulated phosphotyrosine histone dephosphorylation (160-250%) but inhibited phosphoserine histone dephosphorylation (95%). These results suggest the existence of a highly specific phosphotyrosine protein phosphatase activity associated with the plasma membrane of human astrocytoma.

Upregulating CD4+CD25+FOXP3+ regulatory T cells in pancreatic lymph nodes in diabetic NOD mice by adjuvant immunotherapy.

PubMed

Tian, Bole; Hao, Jianqiang; Zhang, Yu; Tian, Lei; Yi, Huimin; O'Brien, Timothy D; Sutherland, David E R; Hering, Bernhard J; Guo, Zhiguang

2009-01-27

Immunotherapy with Complete Freund's adjuvant (CFA) is effective in ameliorating autoimmunity in diabetic nonobese diabetic (NOD) mice. We investigated whether CFA treatment up-regulates CD4+CD25+Foxp3+ regulatory T cells and increases transforming growth factor (TGF)-beta1 production in diabetic NOD mice. New-onset diabetic NOD mice were treated with CFA and exendin-4, a potent analog of glucagon-like peptide-1. Reversal of diabetes was determined by monitoring blood glucose level. Ameliorating autoimmunity through immunoregulation was assessed by adoptive transfer. Regulatory T cells in the peripheral blood, spleen, thymus, and pancreatic nodes were measured. TGF-beta1 in plasma and the insulin content in the pancreas were also measured. Immunostainings for insulin and BrdU were performed. New-onset diabetes could be reversed in 38% of NOD mice treated with CFA alone and in 86% of NOD mice treated with both CFA and exendin-4. Diabetes adoptive transfer by splenocytes from CFA-treated NOD mice was delayed. The percentage of CD4+CD25+Foxp3+ regulatory T cells in the pancreatic lymph nodes of CFA-treated NOD mice was significantly increased at 1, 5, and 15 to 17 weeks after treatment. TGF-beta1 in the plasma of CFA-treated NOD mice was also significantly increased. Combining CFA with exendin-4 treatment significantly increased the insulin content and the numbers of insulin and BrdU double-labeled beta cells in the islets. Our results demonstrated that CFA treatment ameliorates autoimmunity in diabetic NOD mice by up-regulating CD4=CD25+Foxp3+ regulatory T cells and increasing TGF-beta1 production. Exendin-4 enhanced the effect of CFA on reversing diabetes in NOD mice by stimulating beta-cell replication.

Dynamic changes in plasma tissue plasminogen activator, plasminogen activator inhibitor-1 and beta-thromboglobulin content in ischemic stroke.

PubMed

Zhuang, Ping; Wo, Da; Xu, Zeng-Guang; Wei, Wei; Mao, Hui-ming

2015-07-01

The aim of this paper is to investigate the corresponding variations of plasma tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) activities, and beta-thromboglobulin (β-TG) content in patients during different stages of ischemic stroke. Ischemic stroke is a common disease among aging people and its occurrence is associated with abnormalities in the fibrinolytic system and platelet function. However, few reports focus on the dynamic changes in the plasma fibrinolytic system and β-TG content in patients with ischemic stroke. Patients were divided into three groups: acute, convalescent and chronic. Plasma t-PA and PAI-1 activities were determined by chromogenic substrate analysis and plasma β-TG content was detected by radioimmunoassay. Patients in the acute stage of ischemic stroke had significantly increased levels of t-PA activity and β-TG content, but PAI-1 activity was significantly decreased. Negative correlations were found between plasma t-PA and PAI-1 activities and between plasma t-PA activity and β-TG content in patients with acute ischemic stroke. There were significant differences in plasma t-PA and PAI-1 activities in the aged control group, as well as in the acute, convalescent and chronic groups. It can be speculated that the increased activity of t-PA in patients during the acute stage was the result of compensatory function, and that the increase in plasma β-TG level not only implies the presence of ischemic stroke but is likely a cause of ischemic stroke. During the later stages of ischemic stroke, greater attention is required in monitoring levels of PAI-1. Copyright © 2015 Elsevier Ltd. All rights reserved.

Differential distribution of proteins and lipids in detergent-resistant and detergent-soluble domains in rod outer segment plasma membranes and disks.

PubMed

Elliott, Michael H; Nash, Zack A; Takemori, Nobuaki; Fliesler, Steven J; McClellan, Mark E; Naash, Muna I

2008-01-01

Membrane heterogeneity plays a significant role in regulating signal transduction and other cellular activities. We examined the protein and lipid components associated with the detergent-resistant membrane (DRM) fractions from retinal rod outer segment (ROS) disk and plasma membrane-enriched preparations. Proteomics and correlative western blot analysis revealed the presence of alpha and beta subunits of the rod cGMP-gated ion channel and glucose transporter type 1, among other proteins. The glucose transporter was present exclusively in ROS plasma membrane (not disks) and was highly enriched in DRMs, as was the cGMP-gated channel beta-subunit. In contrast, the majority of rod opsin and ATP-binding cassette transporter A4 was localized to detergent-soluble domains in disks. As expected, the cholesterol : fatty acid mole ratio was higher in DRMs than in the corresponding parent membranes (disk and plasma membranes, respectively) and was also higher in disks compared to plasma membranes. Furthermore, the ratio of saturated : polyunsaturated fatty acids was also higher in DRMs compared to their respective parent membranes (disk and plasma membranes). These results confirm that DRMs prepared from both disks and plasma membranes are enriched in cholesterol and in saturated fatty acids compared to their parent membranes. The dominant fatty acids in DRMs were 16 : 0 and 18 : 0; 22 : 6n3 and 18 : 1 levels were threefold higher and twofold lower, respectively, in disk-derived DRMs compared to plasma membrane-derived DRMs. We estimate, based on fatty acid recovery that DRMs account for only approximately 8% of disks and approximately 12% of ROS plasma membrane.

Nonspecific cross-reacting antigen 50/90 is elevated in patients with breast, lung, and colon cancer.

PubMed

Allard, W J; Neaman, I E; Elting, J J; Barnett, T R; Yoshimura, H; Fritsche, H A; Yeung, K K

1994-03-01

A total of 22 genes have been identified in the carcinoembryonic antigen (CEA) gene family. The protein products of this family are highly homologous and include CEA, biliary glycoprotein, nonspecific cross-reacting antigen 50/90 (NCA 50/90), NCA 95, and pregnancy-specific beta-glycoprotein. We used a monoclonal antibody with high affinity to develop a specific enzyme-linked immunosorbent assay (ELISA) method for NCA 50/90 in serum and plasma. Our calibrators were based on affinity-purified recombinant protein from a baculovirus expression system. No significant reactivity with purified CEA, recombinant NCA 95, or recombinant biliary glycoprotein was found by Western blot analysis or in the ELISA method. Only 1 of 15 sera from pregnant women (chorionic gonadotropin > 1000 ng/ml) was positive in the NCA 50/90 ELISA, suggesting that this method does not detect pregnancy-specific glycoprotein. A cutoff value of 18 ng/ml was established based on the 95% value of serum and plasma from 147 healthy volunteers. Only 3 of 31 serum and plasma samples from patients with clinically inactive breast cancer were elevated above the cutoff value, but 44% of 136 samples from patients with clinically active breast cancer were positive. NCA 50/90 measurements were elevated in 7 of 25 patients with active breast cancer whose CEA and CA 15-3 values were below cutoff, and NCA 50/90 values do not correlate with CEA in breast cancer. In addition, we found sensitivities of 70, 39, and 42% for lung cancer, colon cancer, and leukemia, respectively. The sensitivity for non-small cell lung cancer was 85%, however, compared to 50% for small cell lung cancer. Serum from leukemia patients showed an overall sensitivity of 43%, but 71% (10 of 14) sera from patients with chronic myelogenous leukemia were positive compared to, for example, chronic lymphocytic leukemia where 0 of 7 sera had NCA 50/90 values above the cutoff. These studies suggest that NCA 50/90 may have clinical utility in the management of patients with a variety of cancers.

Statistical analysis of m/ n = 2/1 locked and quasi-stationary modes with rotating precursors at DIII-D

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sweeney, Ryan Myles; Choi, W.; La Haye, R. J.

A database has been developed to study the evolution, the nonlinear effects on equilibria, and the disruptivity of locked and quasi-stationary modes with poloidal and toroidal mode numbers m = 2 and n = 1 at DIII-D. The analysis of 22500 discharges shows that more than 18% of disruptions are due to locked or quasi-stationary modes with rotating precursors (not including born locked modes). A parameter formulated by the plasma internal inductance l i divided by the safety factor at 95% of the poloidal flux, q 95, is found to exhibit predictive capability over whether a locked mode will cause a disruption or not, and does so up to hundreds of milliseconds before the disruption. Within 20 ms of the disruption, the shortest distance between the island separatrix and the unperturbed last closed flux surface, referred to as d edge, performs comparably tomore » $${{l}_{i}}/{{q}_{95}}$$ in its ability to discriminate disruptive locked modes. Out of all parameters considered, d edge also correlates best with the duration of the locked mode. Disruptivity following a m/n = 2/1 locked mode as a function of the normalized beta, $${{\\beta}_{\\text{N}}}$$ , is observed to peak at an intermediate value, and decrease for high values. The decrease is attributed to the correlation between $${{\\beta}_{\\text{N}}}$$ and q 95 in the DIII-D operational space. Within 50 ms of a locked mode disruption, average behavior includes exponential growth of the n = 1 perturbed field, which might be due to the 2/1 locked mode. Surprisingly, even assuming the aforementioned 2/1 growth, disruptivity following a locked mode shows little dependence on island width up to 20 ms before the disruption. Separately, greater deceleration of the rotating precursor is observed when the wall torque is large. At locking, modes are often observed to align at a particular phase, which is likely related to a residual error field. Timescales associated with the mode evolution are also studied and dictate the response times necessary for disruption avoidance and mitigation. Lastly, observations of the evolution of $${{\\beta}_{\\text{N}}}$$ during a locked mode, the effects of poloidal beta on the saturated width, and the reduction in Shafranov shift during locking are also presented.« less

Statistical analysis of m/ n = 2/1 locked and quasi-stationary modes with rotating precursors at DIII-D

DOE PAGES

Sweeney, Ryan Myles; Choi, W.; La Haye, R. J.; ...

2016-11-01

A database has been developed to study the evolution, the nonlinear effects on equilibria, and the disruptivity of locked and quasi-stationary modes with poloidal and toroidal mode numbers m = 2 and n = 1 at DIII-D. The analysis of 22500 discharges shows that more than 18% of disruptions are due to locked or quasi-stationary modes with rotating precursors (not including born locked modes). A parameter formulated by the plasma internal inductance l i divided by the safety factor at 95% of the poloidal flux, q 95, is found to exhibit predictive capability over whether a locked mode will cause a disruption or not, and does so up to hundreds of milliseconds before the disruption. Within 20 ms of the disruption, the shortest distance between the island separatrix and the unperturbed last closed flux surface, referred to as d edge, performs comparably tomore » $${{l}_{i}}/{{q}_{95}}$$ in its ability to discriminate disruptive locked modes. Out of all parameters considered, d edge also correlates best with the duration of the locked mode. Disruptivity following a m/n = 2/1 locked mode as a function of the normalized beta, $${{\\beta}_{\\text{N}}}$$ , is observed to peak at an intermediate value, and decrease for high values. The decrease is attributed to the correlation between $${{\\beta}_{\\text{N}}}$$ and q 95 in the DIII-D operational space. Within 50 ms of a locked mode disruption, average behavior includes exponential growth of the n = 1 perturbed field, which might be due to the 2/1 locked mode. Surprisingly, even assuming the aforementioned 2/1 growth, disruptivity following a locked mode shows little dependence on island width up to 20 ms before the disruption. Separately, greater deceleration of the rotating precursor is observed when the wall torque is large. At locking, modes are often observed to align at a particular phase, which is likely related to a residual error field. Timescales associated with the mode evolution are also studied and dictate the response times necessary for disruption avoidance and mitigation. Lastly, observations of the evolution of $${{\\beta}_{\\text{N}}}$$ during a locked mode, the effects of poloidal beta on the saturated width, and the reduction in Shafranov shift during locking are also presented.« less

[Quantifying dialysis efficiency for middle molecules in haemodialysis and in convective and mixed techniques].

PubMed

Casino, F G; Lopez, T

2008-01-01

In contrast to the negative results of the primary analysis, secondary analyses of the HEMO study do support the clinical importance of middle molecule removal. This is in agreement with the findings of large observational studies showing an improvement in mortality and morbidity in dialysis patients treated with high-flux hemodialysis or convective techniques as compared to low-flux hemodialysis. For practical assessment of middle molecule removal, we suggest using the Kt/V of beta2-microglobulin (Kt/Vbeta2-m) with a reference (adequate) value of >or=0.66, which was the average value for the high-flux arm in the HEMO study. For patients on low-flux hemodialysis, where Kt/Vbeta2-m cannot reliably be assessed, we suggest using the Kt/V of vitamin B12 (Kt/VB12), with a reference (adequate) value of >or=0.74, adapted from the findings of the Case Mix Adequacy Study (AJKD 1999). To simplify the routine assessment of these indices, two nomograms are introduced: the first allows to estimate Kt/Vbeta2-m from the post- to pre-dialysis beta2-microglobulin concentration ratio, the second allows to estimate the diffusion dialysis clearance of vitamin B12 from the in vitro dialyzer KoAB12 and actual plasma water flow rate. While waiting for specific trials addressing the issue of dialysis adequacy related to middle molecule removal, clinical experience with the middle molecule indices could provide further quantitative tools for dialysis prescription and favor an increase in dialysis time (or frequency) and/or the use of high-flux hemodialysis and convective techniques.

Higher Plasma Concentration of Food-Specific Antibodies in Persons with Autistic Disorder in Comparison to Their Siblings

ERIC Educational Resources Information Center

Trajkovski, Vladimir; Petlichkovski, Aleksandar; Efinska-Mladenovska, Olivija; Trajkov, Dejan; Arsov, Todor; Strezova, Ana; Ajdinski, Ljubomir; Spiroski, Mirko

2008-01-01

Specific IgA, IgG, and IgE antibodies to food antigens in 35 participants with autistic disorder and 21 of their siblings in the Republic of Macedonia were examined. Statistically significant higher plasma concentration of IgA antibodies against alpha-lactalbumin, beta-lactoglobulin, casein, and gliadin were found in the children with autistic…

Forced swimming and imipramine modify plasma and brain amino acid concentrations in mice.

PubMed

Murakami, Tatsuro; Yamane, Haruka; Tomonaga, Shozo; Furuse, Mitsuhiro

2009-01-05

The relationships between monoamine metabolism and forced swimming or antidepressants have been well studied, however information is lacking regarding amino acid metabolism under these conditions. Therefore, the aim of the present study was to investigate the effects of forced swimming and imipramine on amino acid concentrations in plasma, the cerebral cortex and the hypothalamus in mice. Forced swimming caused cerebral cortex concentrations of L-glutamine, L-alanine, and taurine to be increased, while imipramine treatment caused decreased concentrations of L-glutamate, L-alanine, L-tyrosine, L-methionine, and L-ornithine. In the hypothalamus, forced swimming decreased the concentration of L-serine while imipramine treatment caused increased concentration of beta-alanine. Forced swimming caused increased plasma concentration of taurine, while concentrations of L-serine, L-asparagine, L-glutamine and beta-alanine were decreased. Imipramine treatment caused increased plasma concentration of all amino acid, except for L-aspartate and taurine. In conclusion, forced swimming and imipramine treatment modify central and peripheral amino acid metabolism. These results may aid in the identification of amino acids that have antidepressant-like effects, or may help to refine the dosages of antidepressant drugs.

Localization of Filipin-Sterol Complexes in the Membranes of Beta vulgaris Roots and Spinacia oleracea Chloroplasts 1

PubMed Central

Moeller, Curt H.; Mudd, J. Brian

1982-01-01

Filipin was used as a cytochemical probe for membrane sterols in the root storage tissue of the red beet Beta vulgaris L. and the chloroplasts of Spinacia oleracea L. In unfixed beet tissue, filipin lysed the cells. Freeze-fracture replicas revealed that the filipin-sterol complexes were tightly aggregated in the plasma membrane, while in thin section the complexes corrugated the plasma membrane. If the cells were fixed with glutaraldehyde prior to the filipin treatment, the cell structure was preserved. Filipin-induced lesions were dispersed or clustered loosely in the plasma membrane. A few filipin-sterol complexes were observed in the tonoplast. In spinach chloroplasts, filipin-sterol complexes were limited to the outer membrane of the envelope and were not found in the inner membrane of the envelope or in the lamellar membranes. If the filipin-sterol complexes accurately mapped the distribution of membrane sterols, then sterol was located predominantly in the plasma membrane of the red beet and in the outer membrane of the chloroplast envelope. Furthermore, the sterol may be heterogenously distributed laterally in both these membranes. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:16662716

Acute phase response and plasma carotenoid concentrations in older women: findings from the nun study.

PubMed

Boosalis, M G; Snowdon, D A; Tully, C L; Gross, M D

1996-01-01

This cross-sectional study investigated whether the acute phase response was associated with suppressed circulating levels of antioxidants in a population of 85 Catholic sisters (nuns) ages 77-99 y. Fasting blood was drawn to determine the presence of an acute phase response, as defined by an elevation in the serum concentration of C-reactive protein. Serum concentrations of albumin, thyroxine-binding prealbumin, zinc, copper, and fibrinogen were determined as were plasma concentrations of carotenoids and alpha tocopherol. Results showed that the presence of an acute phase response was associated with (1) an expected significant decrease in the serum concentrations of albumin (p < 0.001) and thyroxine-binding prealbumin (p < 0.001); (2) an expected significant increase in copper (p < 0.001) and fibrinogen (p = 0.003); and (3) a significant decrease in the plasma concentrations of lycopene (p = 0.03), alpha carotene (p = 0.02), beta carotene (p = 0.02), and total carotenoids (p = 0.01). The acute phase response was associated with decreased plasma levels of the antioxidants lycopene, alpha carotene, and beta carotene. This decrease in circulating antioxidants may further compromise antioxidant status and increase oxidative stress and damage in elders.

Kinetic Effects in Parametric Instabilities of Finite Amplitude Alfven Waves in a Drifting Multi-Species Plasma

NASA Astrophysics Data System (ADS)

Maneva, Y. G.; Araneda, J. A.; Poedts, S.

2014-12-01

We consider parametric instabilities of finite-amplitude large-scale Alfven waves in a low-beta collisionless multi-species plasma, consisting of fluid electrons, kinetic protons and a drifting population of minor ions. Complementary to many theoretical studies, relying on fluid or multi-fluid approach, in this work we present the solutions of the parametric instability dispersion relation, including kinetic effects in the parallel direction, along the ambient magnetic field. This provides us with the opportunity to predict the importance of some wave-particle interactions like Landau damping of the daughter ion-acoustic waves for the given pump wave and plasma conditions. We apply the dispersion relation to plasma parameters, typical for low-beta collisionless solar wind close to the Sun. We compare the analytical solutions to the linear stage of hybrid numerical simulations and discuss the application of the model to the problems of preferential heating and differential acceleration of minor ions in the solar corona and the fast solar wind. The results of this study provide tools for prediction and interpretation of the magnetic field and particles data as expected from the future Solar Orbiter and Solar Probe Plus missions.

Pharmacological characterization of the inhibitory activity of beta h-endorphin (beta h-EP), [Arg9,19,24,28,29]-beta h-EP, [Gln8,Gly31]-beta h-EP-Gly-Gly-NH2, in the neuroeffector junction of the mouse vas deferens.

PubMed

Valenzuela, R; Li, C H; Huidobro-Toro, J P

1991-08-01

The inhibitory opioid activities of beta h-endorphin (beta h-EP), its structurally related peptide analogues [Gln8,Gly31]-beta h-EP-Gly-Gly-NH2 (Gly-Gly-beta h-EP), [Arg9,19,24,28,29]-beta h-EP (Arg-beta h-EP) and methionine enkephalin have been examined in the electrically stimulated mouse vas deferens bioassay. All four peptides behaved as full agonists; methionine enkephalin was the most potent followed by Arg-beta h-EP, beta h-EP and Gly-Gly-beta h-EP. Neither Gly-Gly-beta h-EP nor Arg-beta h-EP antagonized the inhibitory action of beta h-EP or methionine enkephalin. An hour of tissue exposure to 30 nM beta-funaltrexamine followed by thorough washing, displaced to the right, in a parallel fashion, the concentration-response curves of beta h-EP and analogues. Whereas the displacement of the concentration response curves was 8 to 10-fold for beta h-EP and Arg-beta h-EP, it was only about 3-fold for Gly-Gly-beta h-EP and methionine enkephalin. Naltrindole was the most potent antagonist of methionine enkephalin with an apparent pA2 of 9.4; its potency as an antagonist of beta h-EP and related analogues was approximately one-tenth of this with pA2 values approximately 8.5. Norbinaltorphimine also antagonized the action of the opioid peptides with pA2 values close to 7.8.

Development of neutral beam injection system by use of washer gun plasma source

NASA Astrophysics Data System (ADS)

Imanaka, Heizo; Kajiya, Hirotaka; Nemoto, Yuichi; Azuma, Akiyoshi; Asai, Tomoaki; Yamada, Takuma; Inomoto, Michiaki; Ono, Yasushi

2008-11-01

For the past ten years, we have been investigating high-beta Spherical Tokamaks (ST) formation using reconnection heating of their axial merging in the TS-4 experiment, University of Tokyo. The produced ST was observed to have the maximum beta of 50-60% right after the merging of two STs. A key issue after the formation is to maintain the produced high-beta ST over 100 Alfven times for its stability check. A new low-cost pulsed neutral beam injection (NBI) system has been arranged for its sustainment experiment. Its advantages are 1) low voltage (15kV for low-field side of ST) and high current (20A), 2) maintenance-free, 3) low-cost. The conventional filament plasma source was replaced by the washer gun to realize air-cooled and maintenance free NBI system. In its startup experiment, we already extracted the maximum beam current of 3.7A for then acceleration voltage of 10kV successfully. This result suggests that the increase in the acceleration voltage and several conditioning work will realize its designed beam parameters of 15kV, 20A.

Structural basis for membrane targeting by the MVB12-associated [beta]-prism domain of the human ESCRT-I MVB12 subunit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boura, Evzen; Hurley, James H.

2012-03-15

MVB12-associated {beta}-prism (MABP) domains are predicted to occur in a diverse set of membrane-associated bacterial and eukaryotic proteins, but their existence, structure, and biochemical properties have not been characterized experimentally. Here, we find that the MABP domains of the MVB12A and B subunits of ESCRT-I are functional modules that bind in vitro to liposomes containing acidic lipids depending on negative charge density. The MABP domain is capable of autonomously localizing to subcellular puncta and to the plasma membrane. The 1.3-{angstrom} atomic resolution crystal structure of the MVB12B MABP domain reveals a {beta}-prism fold, a hydrophobic membrane-anchoring loop, and an electropositivemore » phosphoinositide-binding patch. The basic patch is open, which explains how it senses negative charge density but lacks stereoselectivity. These observations show how ESCRT-I could act as a coincidence detector for acidic phospholipids and protein ligands, enabling it to function both in protein transport at endosomes and in cytokinesis and viral budding at the plasma membrane.« less

Are we optimizing gestational diabetes treatment with glyburide? The pharmacologic basis for better clinical practice.

PubMed

Hebert, M F; Ma, X; Naraharisetti, S B; Krudys, K M; Umans, J G; Hankins, G D V; Caritis, S N; Miodovnik, M; Mattison, D R; Unadkat, J D; Kelly, E J; Blough, D; Cobelli, C; Ahmed, M S; Snodgrass, W R; Carr, D B; Easterling, T R; Vicini, P

2009-06-01

Glyburide's pharmacokinetics (PK) and pharmacodynamics have not been studied in women with gestational diabetes mellitus (GDM). The objective of this study was to assess steady-state PK of glyburide, as well as insulin sensitivity, beta-cell responsivity, and overall disposition indices after a mixed-meal tolerance test (MMTT) in women with GDM (n = 40), nonpregnant women with type 2 diabetes mellitus (T2DM) (n = 26), and healthy pregnant women (n = 40, MMTT only). At equivalent doses, glyburide plasma concentrations were approximately 50% lower in pregnant women than in nonpregnant subjects. The average umbilical cord/maternal plasma glyburide concentration ratio at the time of delivery was 0.7 +/- 0.4. Insulin sensitivity was approximately fivefold lower in women with GDM as compared with healthy pregnant women. Despite comparable beta-cell responsivity indices, the average beta-cell function corrected for insulin resistance was more than 3.5-fold lower in women with glyburide-treated GDM than in healthy pregnant women. Women with GDM in whom glyburide treatment has failed may benefit from alternative medication or dosage escalation; however, fetal safety should be kept in mind.

Treatment Characteristics of Second Order Structure of Proteins Using Low-Pressure Oxygen RF Plasma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hayashi, Nobuya; Nakahigashi, Akari; Kawaguchi, Ryutaro

2010-10-13

Removal of proteins from the surface of medical equipments is attempted using oxygen plasma produced by RF discharge. FTIR spectra indicate that the bonding of C-H and N-H in the casein protein is reduced after irradiation of oxygen plasma. Also, the second order structure of a protein such as {alpha}-helix and {beta}-sheet are modified by the oxygen plasma. Complete removal of casein protein with the concentration of 0.016 mg/cm{sup 2} that is equivalent to remnants on the medical equipment requires two hours avoiding the damage to medical equipments.

The contribution of dissociative processes to the production of atomic lines in hydrogen plasmas

NASA Technical Reports Server (NTRS)

Kunc, J. A.

1985-01-01

The contribution of molecular dissociative processes to the production of atomic lines is considered for a steady-state hydrogen plasma. If the contribution of dissociative processes is dominant, a substantial simplification in plasma diagnostics can be achieved. Numerical calculations have been performed for the production of Balmer alpha, beta, and gamma lines in hydrogen plasmas with medium and large degrees of ionization (x greater than about 0.0001) and for electron temperatures of 5000-45,000 K and electron densities of 10 to the 10th to 10 to the 16th/cu cm.

MHD Stability of Axisymmetric Plasmas In Closed Line Magnetic Fields

NASA Astrophysics Data System (ADS)

Simakov, Andrei N.; Catto, Peter J.; Ramos, Jesus J.; Hastie, R. J.

2003-04-01

The stability of axisymmetric plasmas confined by closed poloidal magnetic field lines is considered. The results are relevant to plasmas in the dipolar fields of stars and planets, as well as the Levitated Dipole Experiment, multipoles, Z pinches and field reversed configurations. The ideal MHD energy principle is employed to study stability of pressure driven Alfvén modes. A point dipole is considered in detail to demonstrate that equilibria exist, which are MHD stable for arbitrary beta. Effects of sound waves and plasma resistivity are investigated next for point dipole equilibria by means of resistive MHD theory.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shaing, K. C.

It is shown that potato orbits in the near-axis region of a high beta tokamak are squeezed in a magnetic well. The squeezing factor is the same as that for the banana orbits derived in an earlier work [Phys. Plasmas 3, 2843 (1996)]. It depends on the energy of the particle. For high-energy particles, the size of the squeezed orbits is independent of their energy. This implies improved confinement for high-energy particles and for high beta tokamaks with advanced fuels.

Electron Heating in Low Mach Number Perpendicular Shocks. II. Dependence on the Pre-shock Conditions

NASA Astrophysics Data System (ADS)

Guo, Xinyi; Sironi, Lorenzo; Narayan, Ramesh

2018-05-01

Recent X-ray observations of merger shocks in galaxy clusters have shown that the post-shock plasma is two-temperature, with the protons being hotter than the electrons. In this work, the second of a series, we investigate the efficiency of irreversible electron heating in perpendicular low Mach number shocks, by means of two-dimensional particle-in-cell simulations. We consider values of plasma beta (the ratio of thermal and magnetic pressures) in the range 4 ≲ β p0 ≲ 32, and sonic Mach number (the ratio of shock speed to pre-shock sound speed) in the range 2 ≲ M s ≲ 5, as appropriate for galaxy cluster shocks. As shown in Paper I, magnetic field amplification—induced by shock compression of the pre-shock field, or by strong proton cyclotron and mirror modes accompanying the relaxation of proton temperature anisotropy—can drive the electron temperature anisotropy beyond the threshold of the electron whistler instability. The growth of whistler waves breaks the electron adiabatic invariance, and allows for efficient entropy production. We find that the post-shock electron temperature T e2 exceeds the adiabatic expectation {T}e2,{ad} by an amount ({T}e2-{T}e2,{ad})/{T}e0≃ 0.044 {M}s({M}s-1) (here, T e0 is the pre-shock temperature), which depends only weakly on the plasma beta over the range 4 ≲ β p0 ≲ 32 that we have explored, as well as on the proton-to-electron mass ratio (the coefficient of ≃0.044 is measured for our fiducial {m}i/{m}e=49, and we estimate that it will decrease to ≃0.03 for the realistic mass ratio). Our results have important implications for current and future observations of galaxy cluster shocks in the radio band (synchrotron emission and Sunyaev–Zel’dovich effect) and at X-ray frequencies.

The beta2- and beta3-adrenoceptor-mediated relaxation induced by fenoterol in guinea pig taenia caecum.

PubMed

Akimoto, Yurie; Horinouchi, Takahiro; Tanaka, Yoshio; Koike, Katsuo

2002-10-01

Fenoterol, a beta2-adrenoceptor selective agonist, belongs to the arylethanolamine class. To understand the receptor subtypes responsible for beta-adrenoceptor-mediated relaxation of guinea pig taenia caecum, we investigated the effect of fenoterol. Fenoterol caused concentration-dependent relaxation of the guinea pig taenia caecum. Propranolol, bupranolol and butoxamine produced shifts of the concentration-response curve for fenoterol. Schild regression analyses carried out for propranolol, butoxamine and bupranolol against fenoterol gave pA2 values of 8.41, 6.33 and 8.44, respectively. However, in the presence of 3 x 10(-4) M atenolol, 10(-4) M butoxamine and 10(-6) M phentolamine to block the beta1-, beta2- and a-adrenoceptor effects, respectively, Schild regression analysis carried out for bupranolol against fenoterol gave pA2 values of 5.80. These results suggest that the relaxant response to fenoterol in the guinea pig taenia caecum is mediated by both the beta2- and the beta3-adrenoceptors.

Agglutination of like-charged red blood cells induced by binding of beta2-glycoprotein I to outer cell surface.

PubMed

Lokar, Marusa; Urbanija, Jasna; Frank, Mojca; Hägerstrand, Henry; Rozman, Blaz; Bobrowska-Hägerstrand, Malgorzata; Iglic, Ales; Kralj-Iglic, Veronika

2008-08-01

Plasma protein-mediated attractive interaction between membranes of red blood cells (RBCs) and phospholipid vesicles was studied. It is shown that beta(2)-glycoprotein I (beta(2)-GPI) may induce RBC discocyte-echinocyte-spherocyte shape transformation and subsequent agglutination of RBCs. Based on the observed beta(2)-GPI-induced RBC cell shape transformation it is proposed that the hydrophobic portion of beta(2)-GPI molecule protrudes into the outer lipid layer of the RBC membrane and increases the area of this layer. It is also suggested that the observed agglutination of RBCs is at least partially driven by an attractive force which is of electrostatic origin and depends on the specific molecular shape and internal charge distribution of membrane-bound beta(2)-GPI molecules. The suggested beta(2)-GPI-induced attractive electrostatic interaction between like-charged RBC membrane surfaces is qualitatively explained by using a simple mathematical model within the functional density theory of the electric double layer, where the electrostatic attraction between the positively charged part of the first domains of bound beta(2)-GPI molecules and negatively charged glycocalyx of the adjacent RBC membrane is taken into account.

Enhanced expressions of mRNA for neuropeptide Y and interleukin 1 beta in hypothalamic arcuate nuclei during adjuvant arthritis-induced anorexia in Lewis rats.

PubMed

Stofkova, Andrea; Haluzik, Martin; Zelezna, Blanka; Kiss, Alexander; Skurlova, Martina; Lacinova, Zdenka; Jurcovicova, Jana

2009-01-01

Food intake is activated by hypothalamic orexigenic neuropeptide Y (NPY), which is mainly under the dual control of leptin and ghrelin. Rat adjuvant arthritis (AA), similarly as human rheumatoid arthritis, is associated with cachexia caused by yet unknown mechanisms. The aim of our study was to evaluate NPY expression in hypothalamic arcuate nuclei (nARC) under the conditions of AA-induced changes in leptin, ghrelin and adiponectin. Since IL-1beta is involved in the central induction of anorexia, we studied its expression in the nARC as well. AA was induced to Lewis rats using complete Freund's adjuvant. On days 12, 15 and 18 after complete Freund's adjuvant injection, the levels of leptin, adiponectin, ghrelin and IL-1beta were determined by RIA or ELISA. The mRNA expressions for NPY, leptin receptor (OB-R), ghrelin receptor (Ghsr) and IL-1beta were determined by TaqMan RT-PCR from isolated nARC. In AA rats, decreased appetite, body mass and epididymal fat stores positively correlated with reduced circulating and epididymal fat leptin and adiponectin. Ghrelin plasma levels were increased. In nARC, mRNA for OB-R, Ghsr and NPY were overexpressed in AA rats. AA rats showed overexpression of mRNA for IL-1beta in nARC while circulating, and spleen IL-1beta was unaltered. During AA, overexpression of orexigenic NPY mRNA in nARC along with enhanced plasma ghrelin and lowered leptin levels occur. Decreased food intake indicates a predominant effect of the anorexigenic pathway. Activated expression of IL-1beta in nARC suggests its role in keeping AA-induced anorexia in progress. The reduction in adiponectin may also contribute to AA-induced anorexia. Copyright 2009 S. Karger AG, Basel.

Inhibition of tracheal vascular extravasation by liposome-encapsulated albuterol in rats.

PubMed

Zhang, W; Guo, L; Nadel, J A; Papahadjopoulos, D

1998-03-01

To develop a liposome-based system for systemic delivery of anti-inflammatory drugs to airways and other inflamed tissues. Postcapillary venular gap junctions open during airway inflammation and allow fluid accumulation and permit molecules (e.g. complement, kininogen) to enter tissues, initiating inflammatory cascades. Beta-adrenergic agonists prevent inflammatory plasma extravasation, but because of their deleterious side effects, they are not used intravenously. When sterically stabilized "stealth" liposomes are injected i.v., they remain in the circulation for long periods. Inflammatory mediators [e.g., substance P(SP)] open postcapillary venular gaps and allow liposomes and their contents to be deposited selectively in the inflamed tissue. We hypothesized that liposomes encapsulating a beta-adrenergic agonist, such as albuterol, would deposit selectively in inflamed airway tissue, where the drug would slowly leak out of the liposomes, resulting in closure of the gaps, thus preventing subsequent inflammatory extravasation. To test this hypothesis, we delivered albuterol-loaded liposomes i.v. in rats. Then we injected SP to open the venular gaps and allow accumulation of the drug-loaded liposomes in airway tissue. We examined whether this treatment resulted in inhibition of subsequent plasma extravasation induced by SP. The results indicate that liposome-encapsulated albuterol inhibits subsequent extravasation, presumably by leaking out of liposomes in airway tissue. This inhibition occurs for prolonged periods of time and with limited side effects compared to the effect of free albuterol. We conclude that liposomes loaded with appropriate drugs, by migrating to inflamed tissue and subsequently inhibiting inflammatory cascades, may be of therapeutic value in inflammatory diseases.

Mechanisms responsible for the trophic effect of beta-adrenoceptors on the I(to) current density in type 1 diabetic rat cardiomyocytes.

PubMed

Setién, Raúl; Alday, Aintzane; Diaz-Asensio, Cristina; Urrutia, Janire; Gallego, Mónica; Casis, Oscar

2013-01-01

In diabetic ventricular myocytes, transient outward potassium current (Ito) amplitude is severely reduced because of the impaired catecholamine release that characterizes diabetic autonomic neuropathy. Sympathetic nervous system exhibits a trophic effect on Ito since incubation of myocytes with noradrenaline restores current amplitude via beta-adrenoceptor (βAR) stimulation. Here, we investigate the intracellular signalling pathway though which incubation of diabetic cardiomyocytes with the βAR agonist isoproterenol recovers Ito amplitude to normal values. Experiments were performed in ventricular myocytes isolated from streptozotocin-diabetic rats. Ito current was recorded by using the patch-clamp technique. Kv4 channel expression was determined by immunofluorescence. Protein-protein interaction was determined by coimmunoprecipitation. Stimulation of βAR activates first a Gαs protein, adenylyl cyclase and Protein Kinase A. PKA-phosphorylated receptor then switches to the Gαi protein. This leads to the activation of the βAR-Kinase-1 and further receptor phosphorylation and arrestin dependent internalization. The internalized receptor-arrestin complex recruits and activates cSrc and the MAPK cascade, where Ras, c-Raf1 and finally ERK1/2 mediate the increase in Kv4.2 and Kv4.3 protein abundance in the plasma membrane. β2AR stimulation activates a Gαs and Gαi protein dependent pathway where the ERK1/2 modulates the Ito current amplitude and the density of the Kv4.2 and Kv4.2 channels in the plasma membrane upon sympathetic stimulation in diabetic heart. Copyright © 2012 S. Karger AG, Basel.

Evaluation of Magnetic Diagnostics for MHD Equilibrium Reconstruction of LHD Discharges

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sontag, Aaron C; Hanson, James D.; Lazerson, Sam

2011-01-01

Equilibrium reconstruction is the process of determining the set of parameters of an MHD equilibrium that minimize the difference between expected and experimentally observed signals. This is routinely performed in axisymmetric devices, such as tokamaks, and the reconstructed equilibrium solution is then the basis for analysis of stability and transport properties. The V3FIT code [1] has been developed to perform equilibrium reconstruction in cases where axisymmetry cannot be assumed, such as in stellarators. The present work is focused on using V3FIT to analyze plasmas in the Large Helical Device (LHD) [2], a superconducting, heliotron type device with over 25 MWmore » of heating power that is capable of achieving both high-beta ({approx}5%) and high density (>1 x 10{sup 21}/m{sup 3}). This high performance as well as the ability to drive tens of kiloamperes of toroidal plasma current leads to deviations in the equilibrium state from the vacuum flux surfaces. This initial study examines the effectiveness of using magnetic diagnostics as the observed signals in reconstructing experimental plasma parameters for LHD discharges. V3FIT uses the VMEC [3] 3D equilibrium solver to calculate an initial equilibrium solution with closed, nested flux surfaces based on user specified plasma parameters. This equilibrium solution is then used to calculate the expected signals for specified diagnostics. The differences between these expected signal values and the observed values provides a starting {chi}{sup 2} value. V3FIT then varies all of the fit parameters independently, calculating a new equilibrium and corresponding {chi}{sup 2} for each variation. A quasi-Newton algorithm [1] is used to find the path in parameter space that leads to a minimum in {chi}{sup 2}. Effective diagnostic signals must vary in a predictable manner with the variations of the plasma parameters and this signal variation must be of sufficient amplitude to be resolved from the signal noise. Signal effectiveness can be defined for a specific signal and specific reconstruction parameter as the dimensionless fractional reduction in the posterior parameter variance with respect to the signal variance. Here, {sigma}{sub i}{sup sig} is the variance of the ith signal and {sigma}{sub j}{sup param} param is the posterior variance of the jth fit parameter. The sum of all signal effectiveness values for a given reconstruction parameter is normalized to one. This quantity will be used to determine signal effectiveness for various reconstruction cases. The next section will examine the variation of the expected signals with changes in plasma pressure and the following section will show results for reconstructing model plasmas using these signals.« less

WHISTLER TURBULENCE FORWARD CASCADE VERSUS INVERSE CASCADE: THREE-DIMENSIONAL PARTICLE-IN-CELL SIMULATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chang, Ouliang; Gary, S. Peter; Wang, Joseph, E-mail: ouliang@usc.edu, E-mail: pgary@lanl.gov, E-mail: josephjw@usc.edu

2015-02-20

We present the results of the first fully three-dimensional particle-in-cell simulations of decaying whistler turbulence in a magnetized, homogeneous, collisionless plasma in which both forward cascades to shorter wavelengths, and inverse cascades to longer wavelengths are allowed to proceed. For the electron beta β {sub e} = 0.10 initial value considered here, the early-time rate of inverse cascade is very much smaller than the rate of forward cascade, so that at late times the fluctuation energy in the regime of the inverse cascade is much weaker than that in the forward cascade regime. Similarly, the wavevector anisotropy in the inversemore » cascade regime is much weaker than that in the forward cascade regime.« less

Superconducting Prototype Cavities for the Spallation Neutron Source (SNS) Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

G. Ciovati; P. Kneisel; K. Davis

2002-06-01

The Spallation Neutron Source project includes a superconducting linac section in the energy range from 186 MeV to 1000 MeV operating at a frequency of 805 MHz at 2.1 K. For this energy range two types of cavities are needed with geometrical Beta-values of Beta=0.61 and Beta=0.81. An aggressive cavity prototyping program is being pursued at JLab, which calls for fabricating and testing of four Beta=0.61 cavities and two Beta=0.81 cavities. Both types consist of six cells made from high purity niobium and feature one HOM coupler of the TESLA type on each beam pipe and a port for amore » high power coaxial input coupler. Three of the four Beta=0.61 cavities will be used for a cryomodule test in early 2002. At this time, four medium beta cavities and one high beta cavity have been completed and tested at JLab. In addition, the three medium beta cavities for the prototype cryomodule have been equipped with the integrated Ti-Helium vessel, successfully retested and will be assembled into a cavity string. Results from the cryo-module test should be available by the time of the conference. The tests on the Beta=0.61 cavity and the Beta=0.81 cavity exceeded the design values for gradient and Q - value: E{sub acc} =10.1 MV/m and Q = 5 x 10{sup 9} at 2.1K for Beta=0.61 and E{sub acc} = 12.3 MV/m and Q=5 x 10{sup 9} at 2.1K for Beta = 0.81. The medium beta cavities reached gradients between E{sub acc} = 15 MV/m and 21 MV/m. This paper will describe the test results obtained with the various cavities, some aspects of the HOM damping at cryogenic temperatures, results from microphonics and Lorentz force detuning tests and the cavity string assembly at the time of this workshop.« less