Relative rates of albumin equilibration in the skin interstitium and lymph during vasodilation

International Nuclear Information System (INIS)

Powers, M.R.; Wallace, J.R.; Bell, D.R.

1986-01-01

The initial equilibration of 125 I-labeled albumin between the vascular and extravascular compartments was studied in hindpaw skin of 6 anesthetized rabbits. Papavarine (200 ug/min) was infused into a small branch of the femoral artery of one limb with the contralateral limb as a control. There was a 1.2-fold increase in lymph flow (p 131 I-labeled albumin injected 10 min before ending the experiment. Endogenous albumin was measured in plasma, lymph, and tissue samples using rocket electroimmunoassay. After 3 hrs of tracer infusion, lymph specific activity relative to plasma was significantly greater in the vasodilated hindlimb (0.30 +/- 0.07 vs 0.13 +/- 0.05; mean +/- SE; p < 0.01). Extravascular specific activity relative to plasma was greater in the vasodilated limb (0.13 +/- 0.02 vs 0.09 +/- 0.02; p < 0.05). Thus, vasodilation increased the rates at which lymph and tissue equilibrate with plasma. Also, the difference between lymph and tissue equilibration was greater in the vasodilated hindlimb

Dihydralazine induces marked cerebral vasodilation in man

DEFF Research Database (Denmark)

Schroeder, T; Sillesen, H

1987-01-01

of dihydralazine was of the same order of magnitude as the effect of 5% CO2 inhalation. These results in normal subjects should be extrapolated to diseased persons only with extreme caution. Still, the very marked and long lasting vasodilation observed suggests that dihydralazine, from a theoretical point of view.......v. xenon-133 technique in seven young, normotensive volunteers before and 15, 60 and 180 min after 6.25 mg i.v. dihydralazine, corresponding approximately to 0.1 mg kg-1 body weight. For comparison the CBF reactivity to inhalation of 5% CO2 in air was investigated. Dihydralazine increased CBF throughout...... the period of study, in median 16, 27 and 23% at the three periods of measurements, respectively. The arterial blood pressure remained unchanged, whereas heart rate increased significantly. During CO2 inhalation, CBF increased on average 29%. Thus, the cerebral vasodilation exerted by a small i.v. dose...

Capillary response to skeletal muscle contraction: evidence that redundancy between vasodilators is physiologically relevant during active hyperaemia.

Science.gov (United States)

Lamb, Iain R; Novielli, Nicole M; Murrant, Coral L

2018-04-15

The current theory behind matching blood flow to metabolic demand of skeletal muscle suggests redundant interactions between metabolic vasodilators. Capillaries play an important role in blood flow control given their ability to respond to muscle contraction by causing conducted vasodilatation in upstream arterioles that control their perfusion. We sought to determine whether redundancies occur between vasodilators at the level of the capillary by stimulating the capillaries with muscle contraction and vasodilators relevant to muscle contraction. We identified redundancies between potassium and both adenosine and nitric oxide, between nitric oxide and potassium, and between adenosine and both potassium and nitric oxide. During muscle contraction, we demonstrate redundancies between potassium and nitric oxide as well as between potassium and adenosine. Our data show that redundancy is physiologically relevant and involved in the coordination of the vasodilator response during muscle contraction at the level of the capillaries. We sought to determine if redundancy between vasodilators is physiologically relevant during active hyperaemia. As inhibitory interactions between vasodilators are indicative of redundancy, we tested whether vasodilators implicated in mediating active hyperaemia (potassium (K + ), adenosine (ADO) and nitric oxide (NO)) inhibit one another's vasodilatory effects through direct application of pharmacological agents and during muscle contraction. Using the hamster cremaster muscle and intravital microscopy, we locally stimulated capillaries with one vasodilator in the absence and the presence of a second vasodilator (10 -7 m S-nitroso-N-acetylpenicillamine (SNAP), 10 -7 m ADO, 10 mm KCl) applied sequentially and simultaneously, and observed the response in the associated upstream 4A arteriole controlling the perfusion of the stimulated capillary. We found that KCl significantly attenuated SNAP- and ADO-induced vasodilatations by ∼49.7% and �

Nonspecific microvascular vasodilation during iontophoresis is attenuated by application of hyperosmolar saline.

Science.gov (United States)

Asberg, A; Holm, T; Vassbotn, T; Andreassen, A K; Hartmann, A

1999-07-01

Iontophoretic administration of acetylcholine chloride (ACh) and sodium nitroprusside (SNP) combined with laser Doppler skin blood perfusion measurements are used for determination of endothelial-dependent and -independent vasodilation. However, the method is biased by nonspecific vasodilation. The primary aim of this study was to investigate if iontophoresis-induced nonspecific vasodilation may be attenuated by addition of high molar concentrations of NaCl to the iontophoresis solutions. Secondary we investigated the applicability of 5 mol/liter NaCl solution as vehicle for ACh and SNP in this method. Skin perfusion changes were determined for iontophoresis of pure vehicles, deionized water and 5 mol/liter NaCl solution, in 12 healthy volunteers. Responses in skin perfusion to iontophoresis of ACh and SNP dissolved in both vehicles were also investigated. Addition of 5 mol/liter NaCl to deionized water significantly attenuated the nonspecific vasodilation and lowered the potential applied over the skin. The inter- and intraindividual coefficients of variation to ACh and SNP responses became, however, higher using hyperosmolar vehicle. During iontophoresis of SNP (in deionized water) we were unable to distinguish between SNP and vehicle effects. This study shows that the nonspecific vasodilation induced by iontophoresis can be attenuated by addition of 5 mol/liter NaCl, possibly due to lower electrical potential over the skin. However, the variability of the method was not improved. When deionized water was used as vehicle the effect of SNP could not be differentiated from that of the vehicle. This was not the case for ACh. Copyright 1999 Academic Press.

Fragile X-Associated Diminished Ovarian Reserve and Primary Ovarian Insufficiency from Molecular Mechanisms to Clinical Manifestations

Directory of Open Access Journals (Sweden)

Limor Man

2017-09-01

Full Text Available Fragile X syndrome (FXS, is caused by a loss-of-function mutation in the FMR1 gene located on the X-chromosome, which leads to the most common cause of inherited intellectual disability in males and the leading single-gene defect associated with autism. A full mutation (FM is represented by more than 200 CGG repeats within the FMR1 gene, resulting in FXS. A FM is inherited from women carrying a FM or a premutation (PM; 55–200 CGG repeats allele. PM is associated with phenotypes distinct from those associated with FM. Some manifestations of the PM are unique; fragile-X-associated tremor/ataxia syndrome (FXTAS, and fragile-X-associated primary ovarian insufficiency (FXPOI, while others tend to be non-specific such as intellectual disability. In addition, women carrying a PM may suffer from subfertility or infertility. There is a need to elucidate whether the impairment of ovarian function found in PM carriers arises during the primordial germ cell (PGC development stage, or due to a rapidly diminishing oocyte pool throughout life or even both. Due to the possibility of expansion into a FM in the next generation, and other ramifications, carrying a PM can have an enormous impact on one’s life; therefore, preconception counseling for couples carrying the PM is of paramount importance. In this review, we will elaborate on the clinical manifestations in female PM carriers and propose the definition of fragile-X-associated diminished ovarian reserve (FXDOR, then we will review recent scientific findings regarding possible mechanisms leading to FXDOR and FXPOI. Lastly, we will discuss counseling, preventative measures and interventions available for women carrying a PM regarding different aspects of their reproductive life, fertility treatment, pregnancy, prenatal testing, contraception and fertility preservation options.

Fragile X-Associated Diminished Ovarian Reserve and Primary Ovarian Insufficiency from Molecular Mechanisms to Clinical Manifestations.

Science.gov (United States)

Man, Limor; Lekovich, Jovana; Rosenwaks, Zev; Gerhardt, Jeannine

2017-01-01

Fragile X syndrome (FXS), is caused by a loss-of-function mutation in the FMR1 gene located on the X-chromosome, which leads to the most common cause of inherited intellectual disability in males and the leading single-gene defect associated with autism. A full mutation (FM) is represented by more than 200 CGG repeats within the FMR1 gene, resulting in FXS. A FM is inherited from women carrying a FM or a premutation (PM; 55-200 CGG repeats) allele. PM is associated with phenotypes distinct from those associated with FM. Some manifestations of the PM are unique; fragile-X-associated tremor/ataxia syndrome (FXTAS), and fragile-X-associated primary ovarian insufficiency (FXPOI), while others tend to be non-specific such as intellectual disability. In addition, women carrying a PM may suffer from subfertility or infertility. There is a need to elucidate whether the impairment of ovarian function found in PM carriers arises during the primordial germ cell (PGC) development stage, or due to a rapidly diminishing oocyte pool throughout life or even both. Due to the possibility of expansion into a FM in the next generation, and other ramifications, carrying a PM can have an enormous impact on one's life; therefore, preconception counseling for couples carrying the PM is of paramount importance. In this review, we will elaborate on the clinical manifestations in female PM carriers and propose the definition of fragile-X-associated diminished ovarian reserve (FXDOR), then we will review recent scientific findings regarding possible mechanisms leading to FXDOR and FXPOI. Lastly, we will discuss counseling, preventative measures and interventions available for women carrying a PM regarding different aspects of their reproductive life, fertility treatment, pregnancy, prenatal testing, contraception and fertility preservation options.

Thallium-201 myocardial imaging during coronary vasodilation induced by oral dipyridamole

International Nuclear Information System (INIS)

Gould, K.L.; Sorenson, S.G.; Albro, P.; Caldwell, J.H.; Chaudhuri, T.; Hamilton, G.W.

1986-01-01

Myocardial perfusion imaging of 201 TI injected during maximum exercise has been an important diagnostic tool for coronary artery disease. Pharmacologic coronary vasodilation by i.v. infusion of dipyridamole may be used in lieu of exercise stress for purposes of diagnostic perfusion imaging. However, i.v. dipyridamole is not currently available from commercial sources for widespread routine use. Accordingly, this study was carried out in order to determine whether high dose, oral dipyridamole would be useful as a coronary vasodilator for purposes of diagnostic perfusion imaging. Fifty-eight patients undergoing diagnostic coronary arteriography also had myocardial perfusion imaging with 201TI under conditions of rest, maximum exercise stress, and high dose oral dipyridamole. Of those patients who had a defect on exercise thallium images, 75% also had a perfusion defect on thallium images after high dose oral dipyridamole. These results indicate that oral dipyridamole causes sufficient coronary arteriolar vasodilation and increase of coronary flow in nonstenotic arteries to identify perfusion defects comparable to those seen on maximum exercise stress in at least 75% of cases. In 25% of patients with exercise defects, no perfusion defect was seen after oral dipyridamole. Thus, oral dipyridamole is a potent coronary vasodilator, comparable to exercise stress in most cases, but in a minority of patients may not be comparable to exercise stress

Systemic low-dose aspirin and clopidogrel independently attenuate reflex cutaneous vasodilation in middle-aged humans.

Science.gov (United States)

Holowatz, Lacy A; Jennings, John D; Lang, James A; Kenney, W Larry

2010-06-01

Chronic systemic platelet cyclooxygenase (COX) inhibition with low-dose aspirin [acetylsalicylic acid (ASA)] significantly attenuates reflex cutaneous vasodilation in middle-aged humans, whereas acute, localized, nonisoform-specific inhibition of vascular COX with intradermal administration of ketorolac does not alter skin blood flow during hyperthermia. Taken together, these data suggest that platelets may be involved in reflex cutaneous vasodilation, and this response is inhibited with systemic pharmacological platelet inhibition. We hypothesized that, similar to ASA, specific platelet ADP receptor inhibition with clopidogrel would attenuate reflex vasodilation in middle-aged skin. In a double-blind crossover design, 10 subjects (53+/-2 yr) were instrumented with four microdialysis fibers for localized drug administration and heated to increase body core temperature [oral temperature (Tor)] 1 degrees C during no systemic drug (ND), and after 7 days of systemic ASA (81 mg) and clopidogrel (75 mg) treatment. Skin blood flow (SkBF) was measured using laser-Doppler flowmetry over each site assigned as 1) control, 2) nitric oxide synthase inhibited (NOS-I; 10 mM NG-nitro-L-arginine methyl ester), 3) COX inhibited (COX-I; 10 mM ketorolac), and 4) NOS-I+COX-I. Data were normalized and presented as a percentage of maximal cutaneous vascular conductance (%CVCmax; 28 mM sodium nitroprusside+local heating to 43 degrees C). During ND conditions, SkBF with change (Delta) in Tor=1.0 degrees C was 56+/-3% CVCmax. Systemic low-dose ASA and clopidogrel both attenuated reflex vasodilation (ASA: 43+/-3; clopidogrel: 32+/-3% CVCmax; both P0.05). NOS-I attenuated vasodilation in ND and ASA (ND: 28+/-6; ASA: 25+/-4% CVCmax; both P0.05). NOS-I+COX-I was not different compared with NOS-I alone in either systemic treatment condition. Both systemic ASA and clopidogrel reduced the time required to increase Tor 1 degrees C (ND: 58+/-3 vs. ASA: 45+/-2; clopidogrel: 39+/-2 min; both Preflex

Relations among impaired coronary flow reserve, left ventricular hypertrophy and thallium perfusion defects in hypertensive patients without obstructive coronary artery disease

International Nuclear Information System (INIS)

Houghton, J.L.; Frank, M.J.; Carr, A.A.; von Dohlen, T.W.; Prisant, L.M.

1990-01-01

Invasive Doppler catheter-derived coronary flow reserve, echocardiographic measurements of left ventricular hypertrophy and intravenous dipyridamole-limited stress thallium-201 scintigraphy were compared in 48 patients (40 were hypertensive or diabetic) with clinical ischemic heart disease and no or minor coronary artery disease. Abnormal vasodilator reserve (ratio less than 3:1) occurred in 50% of the study group and markedly abnormal reserve (less than or equal to 2:1) occurred in 27%. Coronary vasodilator reserve was significantly lower (2.2 +/- 0.8 versus 3.5 +/- 1.3, p = 0.003) and indexed left ventricular mass significantly higher (152.6 +/- 42.2 versus 113.6 +/- 24.0 g, p = 0.0007) in patients with a positive (n = 11) versus a negative (n = 32) thallium perfusion scan. Coronary flow reserve was linearly related in coronary basal flow velocity as follows: y = -0.17x + 4.59; r = -0.57; p = 0.00002. The decrement in flow reserve was not linearly related to the degree of left ventricular hypertrophy. Abnormal vasodilator reserve subsets found in hypertensive patients were defined on the basis of basal flow velocity, indexed left ventricular mass and clinical factors. In this series, diabetes did not cause a detectable additional decrement in flow reserve above that found with hypertension alone. These findings demonstrate that thallium perfusion defects are associated with depressed coronary vasodilator reserve in hypertensive patients without obstructive coronary artery disease. Left ventricular hypertrophy by indexed mass criteria is predictive of which hypertensive patients are likely to have thallium defects

Sex- and limb-specific differences in the nitric oxide-dependent cutaneous vasodilation in response to local heating

Science.gov (United States)

Stanhewicz, Anna E.; Greaney, Jody L.; Larry Kenney, W.

2014-01-01

Local heating of the skin is commonly used to assess cutaneous microvasculature function. Controversy exists as to whether there are limb or sex differences in the nitric oxide (NO)-dependent contribution to this vasodilation, as well as the NO synthase (NOS) isoform mediating the responses. We tested the hypotheses that 1) NO-dependent vasodilation would be greater in the calf compared with the forearm; 2) total NO-dependent dilation would not be different between sexes within limb; and 3) women would exhibit greater neuronal NOS (nNOS)-dependent vasodilation in the calf. Two microdialysis fibers were placed in the skin of the ventral forearm and the calf of 19 (10 male and 9 female) young (23 ± 1 yr) adults for the local delivery of Ringer solution (control) or 5 mM Nω-propyl-l-arginine (NPLA; nNOS inhibition). Vasodilation was induced by local heating (42°C) at each site, after which 20 mM NG-nitro-l-arginine methyl ester (l-NAME) was perfused for within-site assessment of NO-dependent vasodilation. Cutaneous vascular conductance (CVC) was calculated as laser-Doppler flux/mean arterial pressure and normalized to maximum (28 mM sodium nitroprusside, 43°C). Total NO-dependent vasodilation in the calf was lower compared with the forearm in both sexes (Ringer: 42 ± 5 vs. 62 ± 4%; P 0.05). These data suggest that the NO-dependent component of local heating-induced cutaneous vasodilation is lower in the calf compared with the forearm. Contrary to our original hypothesis, there was no contribution of nNOS to NO-dependent vasodilation in either limb during local heating. PMID:25100074

Assisted Hatching and Intracytoplasmic Sperm Injection are not Associated with Improved Outcomes in ART Cycles for Diminished Ovarian Reserve: An Analysis of US Cycles from 2004–2011

Science.gov (United States)

Butts, Samantha F.; Owen, Carter; Mainigi, Monica; Senapati, Suneeta; Seifer, David B.; Dokras, Anuja

2014-01-01

Objective To investigate the impact of intracytoplasmic sperm injection (ICSI) and assisted hatching (AH) on ART outcomes in cycles with diminished ovarian reserve (DOR) as the primary diagnosis. Design Retrospective cohort study of cycles from the SART-CORS database. Setting NA. Patient(s) A total of 422,949 fresh, non-donor, initial ART cycles of which 8,597 were diagnosed with only elevated FSH and 38,926 were diagnosed with only DOR according to the SART DOR categorization. Intervention(s) None. Main Outcome Measure(s) Live birth and clinical pregnancy rates. Result(s) ICSI and AH were associated with diminished odds of live birth in SART DOR only cycles (AOR, 95% CI 0.88, 0.81–0.96 for ICSI; AOR, 95% CI 0.77 0.71–0.84 for AH). No association between either ICSI or AH in Elevated FSH only cycles was observed. The combination of ICSI and AH resulted in significantly lower odds of live birth in SART DOR only cycles but not in Elevated FSH only cycles. Conclusion(s) In initial ART cycles for which the only indication relates to a diagnosis of diminished ovarian reserve, assisted hatching and ICSI are not associated with improved live birth rates. PMID:25086790

Acetylcholine-induced vasodilation in the uterine vascular bed of pregnant rats with adriamycin-induced nephrosis.

Science.gov (United States)

Yousif, Mariam H; Adeagbo, Ayotunde S; Kadavil, Elizabeth A; Chandrasekhar, Bindu; Oriowo, Mabayoje A

2002-01-01

This project was designed to study endothelium-dependent vasodilation in the uterine vascular bed during experimentally induced preeclampsia in rats. Uterine vascular beds were isolated from non-pregnant and pregnant rats with or without treatment with adriamycin (ADR) and perfused with physiological solution. Thereafter, vasodilator responses to acetylcholine were recorded. RECORDS: Pregnant ADR-treated rats displayed symptoms of preeclampsia including hypertension and proteinuria. Blood pressure was 110.0 +/- 4.7 mm Hg (n = 5) in control pregnant rats and 136.0 +/- 5.3 mm Hg (n = 5) in ADR-treated pregnant rats, and urinary protein concentrations were 0.35 mg/ml (n = 5) and 13.2 +/- 3.6 mg/ml (n = 9), respectively. Both blood pressure and proteinuria values were significantly (p acetylcholine-induced dose-dependent vasodilator responses in the vascular beds were not significantly different between the pregnant and nonpregnant rats. Although acetylcholine-induced vasodilation was significantly reduced by N omega-nitro-L-arginine methyl ester hydrochloride (L-NAME) in both groups, the residual response to acetylcholine was not affected by indomethacin, suggesting that prostanoids were not involved in this response. The L-NAME-resistant component, endothelium-derived hyperpolarizing factor (EDHF), was greater in ADR-treated uterine beds than in those of the controls, indicating a significant contribution from EDHF in these vessels. In the presence of an elevated external potassium ion concentration, acetylcholine produced similar vasodilator responses, indicating that the release of nitric oxide was not impaired. These results indicate that endothelium-dependent vasodilation was not impaired in this model of preeclampsia.

Luteal-phase ovarian stimulation increases the number of mature oocytes in older women with severe diminished ovarian reserve.

Science.gov (United States)

Rashtian, Justin; Zhang, John

2018-03-22

In older women with severe diminished ovarian response (DOR), in vitro fertilization (IVF) treatment is much less successful due to the low number of mature oocytes collected. The objective of this study was to assess whether follicular-phase stimulation (FPS) and luteal-phase stimulation (LPS) in the same menstrual cycle (double ovarian stimulation) in older women with severe DOR will produce a higher number of oocytes compared to FPS alone. Women with DOR (n = 69; mean age = 42.4) who underwent double ovarian stimulation for IVF were included. Women underwent ovarian stimulation in FPS using clomiphene citrate, letrozole, and gonadotropins followed by oocyte retrieval. The next day following oocyte retrieval, women underwent a second ovarian stimulation (LPS) using the same medications followed by a second oocyte retrieval. T-test was performed in order to compare the clinical characteristics and outcome in the same participant between FPS and LPS. Although antral follicle count at the start of FPS tended to be higher than at the start of the LPS cycle, there was no statistically significant difference between the duration of ovarian stimulation, peak estradiol levels, number of small (FPS alone. The addition of LPS to the conventional FPS increases the number of mature oocytes retrieved in the same IVF cycle, thus potentially increasing the chances of pregnancy in older women with severe DOR. AFC: antral follicle count; BMI: body mass index; DOR: diminished ovarian reserve; E2: estradiol; FPS: follicular-phase stimulation; FSH: follicle stimulating hormone; GnRH: gonadotropin-releasing hormone; HCG: human chorionic gonadotropin; IRB: institutional review board; IVF: in vitro fertilization; LH: luteinizing hormone; LPS: luteal-phase stimulation; MII: metaphase II.

Opening the microcirculation: can vasodilators be useful in sepsis?

NARCIS (Netherlands)

Buwalda, Mattijn; Ince, Can

2002-01-01

Objective: A prominent feature of sepsis is dysfunction of the microcirculation, with impaired perfusion and regional tissue oxygenation causing a deficit in oxygen extraction. If shunting of oxygen transport past closed hypoxic microcirculatory beds is responsible for this, vasodilator therapy,

Wearing graduated compression stockings augments cutaneous vasodilation in heat-stressed resting humans.

Science.gov (United States)

Fujii, Naoto; Nikawa, Toshiya; Tsuji, Bun; Kondo, Narihiko; Kenny, Glen P; Nishiyasu, Takeshi

2017-05-01

We investigated whether graduated compression induced by stockings enhances cutaneous vasodilation in passively heated resting humans. Nine habitually active young men were heated at rest using water-perfusable suits, resulting in a 1.0 °C increase in body core temperature. Heating was repeated twice on separate occasions while wearing either (1) stockings that cause graduated compression (pressures of 26.4 ± 5.3, 17.5 ± 4.4, and 6.1 ± 2.0 mmHg at the ankle, calf, and thigh, respectively), or (2) loose-fitting stockings without causing compression (Control). Forearm vascular conductance during heating was evaluated by forearm blood flow (venous occlusion plethysmography) divided by mean arterial pressure to estimate heat-induced cutaneous vasodilation. Body core (esophageal), skin, and mean body temperatures were measured continuously. Compared to the Control, forearm vascular conductance during heating was higher with graduated compression stockings (e.g., 23.2 ± 5.5 vs. 28.6 ± 5.8 units at 45 min into heating, P = 0.001). In line with this, graduated compression stockings resulted in a greater sensitivity (27.5 ± 8.3 vs. 34.0 ± 9.4 units °C -1 , P = 0.02) and peak level (25.5 ± 5.8 vs. 29.7 ± 5.8 units, P = 0.004) of cutaneous vasodilation as evaluated from the relationship between forearm vascular conductance with mean body temperature. In contrast, the mean body temperature threshold for increases in forearm vascular conductance did not differ between the Control and graduated compression stockings (36.5 ± 0.1 vs. 36.5 ± 0.2 °C, P = 0.85). Our results show that graduated compression associated with the use of stockings augments cutaneous vasodilation by modulating sensitivity and peak level of cutaneous vasodilation in relation to mean body temperature. However, the effect of these changes on whole-body heat loss remains unclear.

VIP/PACAP receptor mediation of cutaneous active vasodilation during heat stress in humans.

Science.gov (United States)

Kellogg, Dean L; Zhao, Joan L; Wu, Yubo; Johnson, John M

2010-07-01

Vasoactive intestinal peptide (VIP) is implicated in cutaneous active vasodilation in humans. VIP and the closely related pituitary adenylate cyclase activating peptide (PACAP) act through several receptor types: VIP through VPAC1 and VPAC2 receptors and PACAP through VPAC1, VPAC2, and PAC1 receptors. We examined participation of VPAC2 and/or PAC1 receptors in cutaneous vasodilation during heat stress by testing the effects of their specific blockade with PACAP6-38. PACAP6-38 dissolved in Ringer's was administered by intradermal microdialysis at one forearm site while a control site received Ringer's solution. Skin blood flow was monitored by laser-Doppler flowmetry (LDF). Blood pressure was monitored noninvasively and cutaneous vascular conductance (CVC) calculated. A 5- to 10-min baseline period was followed by approximately 70 min of PACAP6-38 (100 microM) perfusion at one site in normothermia and a 3-min period of body cooling. Whole body heating was then performed to engage cutaneous active vasodilation and was maintained until CVC had plateaued at an elevated level at all sites for 5-10 min. Finally, 58 mM sodium nitroprusside was perfused through both microdialysis sites to effect maximal vasodilation. No CVC differences were found between control and PACAP6-38-treated sites during normothermia (19 +/- 3%max untreated vs. 20 +/- 3%max, PACAP6-38 treated; P > 0.05 between sites) or cold stress (11 +/- 2%max untreated vs. 10 +/- 2%max, PACAP6-38 treated, P > 0.05 between sites). PACAP6-38 attenuated the increase in CVC during whole body heating when compared with untreated sites (59 +/- 3%max untreated vs. 46 +/- 3%max, PACAP6-38 treated, P < 0.05). We conclude that VPAC2 and/or PAC1 receptor activation is involved in cutaneous active vasodilation in humans.

Circulating microparticles from patients with valvular heart disease and cardiac surgery inhibit endothelium-dependent vasodilation.

Science.gov (United States)

Fu, Li; Hu, Xiao-Xia; Lin, Ze-Bang; Chang, Feng-Jun; Ou, Zhi-Jun; Wang, Zhi-Ping; Ou, Jing-Song

2015-09-01

Vascular function is very important for maintaining circulation after cardiac surgery. Circulating microparticles (MPs) generated in various diseases play important roles in causing inflammation, coagulation, and vascular injury. However, the impact of MPs generated from patients who have valvular heart disease (VHD), before and after cardiac surgery, on vascular function remains unknown. This study is designed to investigate the impact of such MPs on vasodilation. Microparticles were isolated from age-matched healthy subjects and patients who had VHD, before cardiac surgery, and at 12 hours and 72 hours afterward. The number of MPs was measured and compared. Effects evaluated were of the impact of MPs on: vasodilation of mice aorta; the phosphorylation and expression of Akt, endothelial nitric oxide synthase (eNOS), protein kinase C-βII (PKC-βII), and p70 ribosomal protein S6 kinase (p70S6K); expression of caveolin-1; the association of eNOS with heat shock protein 90 (HSP90); and generation of nitric oxide and superoxide anion of human umbilical vein endothelial cells. Compared with the healthy subjects, VHD patients had significantly higher levels of circulating MPs and those MPs before cardiac surgery can: impair endothelium-dependent vasodilation; inhibit phosphorylation of Akt and eNOS; increase activation of PKC-βII and p70S6K; enhance expression of caveolin-1; reduce the association of HSP90 with eNOS; decrease nitric oxide production, and increase superoxide anion generation. These deleterious effects were even stronger in postoperative MPs. Our data demonstrate that MPs generated from VHD patients before and after cardiac surgery contributed to endothelial dysfunction, by uncoupling and inhibiting eNOS. Circulating MPs are potential therapeutic targets for the maintenance of vascular function postoperatively. Copyright © 2015 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Endothelin B receptor blockade attenuates pulmonary vasodilation in oxygen-ventilated fetal lambs.

Science.gov (United States)

Ivy, D Dunbar; Lee, Dong-Seok; Rairigh, Robyn L; Parker, Thomas A; Abman, Steven H

2004-01-01

Endothelin-1 (ET-1) contributes to the regulation of pulmonary vascular tone in the normal ovine fetus and in models of perinatal pulmonary hypertension. In the fetal lamb lung, the effects of ET-1 depend on the balance of at least two endothelin receptor subtypes: ETA and ETB. ETA receptors are located on smooth muscle cells and mediate vasoconstriction and smooth muscle proliferation. Stimulation of endothelial ETB receptors causes vasodilation through release of nitric oxide and also functions to remove ET-1 from the circulation. However, whether activation of ETB receptors contributes to the fall in pulmonary vascular tone at birth is unknown. To determine the role of acute ETB receptor blockade in pulmonary vasodilation in response to birth-related stimuli, we studied the hemodynamic effects of selective ETB receptor blockade with BQ-788 during mechanical ventilation with low (<10%) and high FiO2 (100%) in near-term fetal sheep. Intrapulmonary infusion of BQ-788 did not change left pulmonary artery (LPA) blood flow and pulmonary vascular resistance (PVR) at baseline. In comparison with controls, BQ-788 treatment attenuated the rise in LPA flow with low and high FiO2 ventilation (p <0.001 vs. control for each FiO2 concentration). PVR progressively decreased during mechanical ventilation with low and high FiO2 in both groups, but PVR remained higher after BQ-788 treatment throughout the study period (p <0.001). We conclude that selective ETB receptor blockade attenuates pulmonary vasodilation at birth. We speculate that ETB receptor stimulation contributes to pulmonary vasodilation at birth in the ovine fetus.

Identification of a salivary vasodilator in the primary North American vector of bluetongue viruses, Culicoides variipennis.

Science.gov (United States)

Perez de Leon, A A; Ribeiro, J M; Tabachnick, W J; Valenzuela, J G

1997-09-01

Several species of Culicoides biting midges are important pests and vectors of pathogens affecting humans and other animals. Bluetongue is the most economically important arthropod-borne animal disease in the United States. Culicoides variipennis is the primary North American vector of the bluetongue viruses. A reddish halo surrounding a petechial hemorrhage was noticed at the site of C. variipennis blood feeding in previously unexposed sheep and rabbits. Salivary gland extracts of nonblood-fed C. variipennis injected intradermally into sheep and rabbits induced cutaneous vasodilation in the form of erythema. A local, dose-dependent erythema, without edema or pruritus, was noted 30 min after injection. Erythema was inapparent with salivary gland extracts obtained after blood feeding. This observation suggested that the vasodilatory activity was inoculated into the host skin at the feeding site. The vasodilatory activity was insoluble in ethanol and destroyed by trypsin or chymotrypsin, which indicated that vasodilation was due to a protein. The association of cutaneous vasodilation with a salivary protein was corroborated by reversed-phase, high-performance liquid chromatography (HPLC). Fractionation of salivary gland extracts by molecular sieving HPLC resulted in maximal vasodilatory activity that coeluted with a protein having a relative molecular weight (MWr) of 22.45 kD. The C. variipennis vasodilator appears to be biologically active at the nanogram level. This vasodilator likely assists C. variipennis during feeding by increasing blood flow from host superficial blood vessels surrounding the bite site. The identification of a salivary vasodilator in C. variipennis may have implications for the transmission of Culicoides-borne pathogens and in the development of dermatitis resulting from the sensitization of humans and animals to Culicoides salivary antigens.

Role of calcium-activated potassium channels with small conductance in bradykinin-induced vasodilation of porcine retinal arterioles

DEFF Research Database (Denmark)

Dalsgaard, Thomas; Kroigaard, Christel; Bek, Toke

2009-01-01

PURPOSE: Endothelial dysfunction and impaired vasodilation may be involved in the pathogenesis of retinal vascular diseases. In the present study, the mechanisms underlying bradykinin vasodilation were examined and whether calcium-activated potassium channels of small (SK(Ca)) and intermediate (IK...

Psychological and emotional concomitants of infertility diagnosis in women with diminished ovarian reserve or anatomical cause of infertility.

Science.gov (United States)

Nicoloro-SantaBarbara, Jennifer M; Lobel, Marci; Bocca, Silvina; Stelling, James R; Pastore, Lisa M

2017-07-01

To examine the magnitude and predictors of emotional reactions to an infertility diagnosis in two groups of women: those with diminished ovarian reserve (DOR), and those clinically diagnosed with an anatomical cause of infertility (ACI). Cross-sectional study. Academic and private fertility clinics. Women diagnosed with DOR (n = 51) and women diagnosed with ACI (n = 51). Not applicable. Fertility Problem Inventory (infertility distress), Rosenberg Self-Esteem Scale, Health Orientation Scale (emotional reactions to receiving a diagnosis). Women with DOR had statistically significantly higher infertility distress scores than women with ACI and higher scores on subscales assessing distress from social concerns, sexual concerns, and a need for parenthood. In both groups, higher self-esteem was associated with lower infertility distress. Hierarchical multiple regression analyses revealed that for women with DOR and those with ACI lower infertility distress but not self-esteem predicted a more positive emotional reaction toward receiving a fertility diagnosis. Women diagnosed with DOR have greater infertility distress but similar self-esteem and emotional reactions to their diagnosis compared with women who have an anatomical cause of infertility. These results suggest that for both groups distress surrounding infertility itself may influence the way women respond to learning the cause of their infertility. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Does the instantaneous wave-free ratio approximate the fractional flow reserve?

NARCIS (Netherlands)

Johnson, Nils P.; Kirkeeide, Richard L.; Asrress, Kaleab N.; Fearon, William F.; Lockie, Timothy; Marques, Koen M. J.; Pyxaras, Stylianos A.; Rolandi, M. Cristina; van 't Veer, Marcel; de Bruyne, Bernard; Piek, Jan J.; Pijls, Nico H. J.; Redwood, Simon; Siebes, Maria; Spaan, Jos A. E.; Gould, K. Lance

2013-01-01

This study sought to examine the clinical performance of and theoretical basis for the instantaneous wave-free ratio (iFR) approximation to the fractional flow reserve (FFR). Recent work has proposed iFR as a vasodilation-free alternative to FFR for making mechanical revascularization decisions. Its

Mechanistic electronic model to simulate and predict the effect of heat stress on the functional genomics of HO-1 system: Vasodilation.

Science.gov (United States)

Aggarwal, Yogender; Karan, Bhuwan Mohan; Das, Barda Nand; Sinha, Rakesh Kumar

2010-05-01

The present work is concerned to model the molecular signalling pathway for vasodilation and to predict the resting young human forearm blood flow under heat stress. The mechanistic electronic modelling technique has been designed and implemented using MULTISIM 8.0 and an assumption of 1V/ degrees C for prediction of forearm blood flow and the digital logic has been used to design the molecular signalling pathway for vasodilation. The minimum forearm blood flow has been observed at 35 degrees C (0 ml 100 ml(-1)min(-1)) and the maximum at 42 degrees C (18.7 ml 100 ml(-1)min(-1)) environmental temperature with respect to the base value of 2 ml 100 ml(-1)min(-1). This model may also enable to identify many therapeutic targets that can be used in the treatment of inflammations and disorders due to heat-related illnesses. 2010 Elsevier Ltd. All rights reserved.

Differences in finger skin contact cooling response between an arterial occlusion and a vasodilated condition.

Science.gov (United States)

Jay, Ollie; Havenith, George

2006-05-01

To assess the presence and magnitude of the effect of skin blood flow on finger skin cooling on contact with cold objects against the background of circulatory disorder risks in occupational exposures, this study investigates the effect of zero vs. close-to-maximal hand blood flow on short-term (cooling response at a contact pressure that allows capillary perfusion of the distal pulp of the fingertip. Six male volunteers touched a block of aluminium with a finger contact force of 0.5 N at a temperature of -2 degrees C under a vasodilated and an occluded condition. Before both conditions, participants were required to exercise in a hot room for > or = 30 min for cutaneous vasodilation to occur (increase in rectal temperature of 1 degrees C). Under the vasodilated condition, forearm blood flow rate rose as high as 16.8 ml.100 ml(-1).min(-1). Under the occluded condition, the arm was exsanguinated, after which a blood pressure cuff was secured on the wrist inducing arterial occlusion. Contact temperature of the finger pad during the subsequent cold contact exposure was measured. No significant difference was found between the starting skin temperatures for the two blood flow conditions, but a distinct difference in shape of the contact cooling curve was apparent between the two blood flow conditions, with Newtonian cooling observed under the occluded condition, whereas a rewarming of the finger skin toward the end of the exposure occurred for the vasodilated condition. Blood flow was found to significantly increase contact temperature from 40 s onward (P cooling during a vasodilated state.

Rhynchophylla total alkaloid rescues autophagy, decreases oxidative stress and improves endothelial vasodilation in spontaneous hypertensive rats.

Science.gov (United States)

Li, Chao; Jiang, Feng; Li, Yun-Lun; Jiang, Yue-Hua; Yang, Wen-Qing; Sheng, Jie; Xu, Wen-Juan; Zhu, Qing-Jun

2018-03-01

Autophagy plays an important role in alleviating oxidative stress and stabilizing atherosclerotic plaques. However, the potential role of autophagy in endothelial vasodilation function has rarely been studied. This study aimed to investigate whether rhynchophylla total alkaloid (RTA) has a positive role in enhancing autophagy through decreasing oxidative stress, and improving endothelial vasodilation. In oxidized low-density lipoprotein (ox-LDL)-treated human umbilical vein endothelial cells (HUVECs), RTA (200 mg/L) significantly suppressed ox-LDL-induced oxidative stress through rescuing autophagy, and decreased cell apoptosis. In spontaneous hypertensive rats (SHR), administration of RTA (50 mg·kg -1 ·d -1 , ip, for 6 weeks) improved endothelin-dependent vasodilation of thoracic aorta rings. Furthermore, RTA administration significantly increased the antioxidant capacity and alleviated oxidative stress through enhancing autophagy in SHR. In ox-LDL-treated HUVECs, we found that the promotion of autophagy by RTA resulted in activation of the AMP-activated protein kinase (AMPK) signaling pathway. Our results show that RTA treatment rescues the ox-LDL-induced autophagy impairment in HUVECs and improves endothelium-dependent vasodilation function in SHR.

Crosstalk between nitrite, myoglobin and reactive oxygen species to regulate vasodilation under hypoxia.

Directory of Open Access Journals (Sweden)

Matthias Totzeck

Full Text Available The systemic response to decreasing oxygen levels is hypoxic vasodilation. While this mechanism has been known for more than a century, the underlying cellular events have remained incompletely understood. Nitrite signaling is critically involved in vessel relaxation under hypoxia. This can be attributed to the presence of myoglobin in the vessel wall together with other potential nitrite reductases, which generate nitric oxide, one of the most potent vasodilatory signaling molecules. Questions remain relating to the precise concentration of nitrite and the exact dose-response relations between nitrite and myoglobin under hypoxia. It is furthermore unclear whether regulatory mechanisms exist which balance this interaction. Nitrite tissue levels were similar across all species investigated. We then investigated the exact fractional myoglobin desaturation in an ex vivo approach when gassing with 1% oxygen. Within a short time frame myoglobin desaturated to 58±12%. Given that myoglobin significantly contributes to nitrite reduction under hypoxia, dose-response experiments using physiological to pharmacological nitrite concentrations were conducted. Along all concentrations, abrogation of myoglobin in mice impaired vasodilation. As reactive oxygen species may counteract the vasodilatory response, we used superoxide dismutase and its mimic tempol as well as catalase and ebselen to reduce the levels of reactive oxygen species during hypoxic vasodilation. Incubation of tempol in conjunction with catalase alone and catalase/ebselen increased the vasodilatory response to nitrite. Our study shows that modest hypoxia leads to a significant nitrite-dependent vessel relaxation. This requires the presence of vascular myoglobin for both physiological and pharmacological nitrite levels. Reactive oxygen species, in turn, modulate this vasodilation response.

Evidence for a role of nitric oxide in hindlimb vasodilation induced by hypothalamic stimulation in anesthetized rats

Directory of Open Access Journals (Sweden)

Marcos L. Ferreira-Neto

2005-06-01

Full Text Available Electrical stimulation of the hypothalamus produces cardiovascular adjustments consisting of hypertension, tachycardia, visceral vasoconstriction and hindlimb vasodilation. Previous studies have demonstrated that hindlimb vasodilation is due a reduction of sympathetic vasoconstrictor tone and to activation of beta2-adrenergic receptors by catecholamine release. However, the existence of a yet unidentified vasodilator mechanism has also been proposed. Recent studies have suggested that nitric oxide (NO may be involved. The aim of the present study was to investigate the role of NO in the hindquarter vasodilation in response to hypothalamic stimulation. In pentobarbital-anesthetized rats hypothalamic stimulation (100 Hz, 150µA, 6 s produced hypertension, tachycardia, hindquarter vasodilation and mesenteric vasoconstriction. Alpha-adrenoceptor blockade with phentolamine (1.5 mg/kg, iv plus bilateral adrenalectomy did not modify hypertension, tachycardia or mesenteric vasoconstriction induced by hypothalamic stimulation. Hindquarter vasodilation was strongly reduced but not abolished. The remaining vasodilation was completely abolished after iv injection of the NOS inhibitor L-NAME (20 mg/kg, iv. To properly evaluate the role of the mechanism of NO in hindquarter vasodilation, in a second group of animals L-NAME was administered before alpha-adrenoceptor blockade plus adrenalectomy. L-NAME treatment strongly reduced hindquarter vasodilation in magnitude and duration. These results suggest that NO is involved in the hindquarter vasodilation produced by hypothalamic stimulation.Em animais anestesiados a EE do hipotálamo produz um padrão de ajustes cardiovasculares caracterizado por hipertensão arterial, taquicardia, vasodilatação muscular e vasoconstrição mesentérica, entretanto, os mecanismos periféricos envolvidos nestes ajustes cardiovasculares ainda não foram completamente esclarecidos. O presente estudo teve como objetivo caracterizar

Cold induced peripheral vasodilation at high altitudes- a field study

NARCIS (Netherlands)

Daanen, H.A.M.; Ruiten, H.J.A. van

2000-01-01

A significant reduction in cold-induced vasodilation (CIVD) is observed at high altitudes. No agreement is found in the literature about acclimatization effects on CIVD. Two studies were performed to investigate the effect of altitude acclimatization on CIVD. In the first study 13 male subjects

Vasodilator stress impairs the left ventricular function obtained with gated single-photon emission computed tomography in patients with known or suspected coronary artery disease

International Nuclear Information System (INIS)

Odagiri, Keiichi; Uehara, Akihiko; Kurata, Chinori

2010-01-01

Transient ischemic dilatation (TID) and post-stress dysfunction of the left ventricle (LV) are important markers of severe coronary artery disease (CAD). To clarify the effects of stressor type on TID and post-stress LV dysfunction, changes in LV measurements were compared between patients with exercise- or vasodilator-induced stress. The 689 patients referred for technetium-99m tetrofosmin myocardial perfusion imaging were included. Patients were stressed with either a vasodilator (n=236) or exercise (n=453). LV measurements were obtained with electrocardiogram (ECG)-gated single photon emission computed tomography (SPECT). LV end-diastolic and end-systolic volume indexes (LVEDVI, LVESVI) increased and LV ejection fraction (LVEF) decreased after stress in the vasodilator-stress group. Vasodilator-stress and the summed difference score (SDS) were independent variables that decreased LVEF after stress. Even in patients without reversible defects, vasodilator-stress impaired LV function. There were no differences in the stress-to-rest ratios of LVEDVI (rEDV) and LVESVI (rESV) among patients with normal myocardial perfusion, fixed defects and reversible defects in the vasodilator-stress group, whereas in the exercise-stress group, rESV was significantly higher in the patients with reversible defects than in those without reversible defects. Within the vasodilator-stress group, neither rEDV nor rESV correlated with the SDS. Vasodilator-stress by itself decreases LVEF after stress. TID should be carefully interpreted when vasodilator-stress is used to detect severe CAD. (author)

Reversible diminished renal sup(99m)Tc-DMSA uptake during converting-enzyme inhibition in a patient with renal artery stenosis

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Kremer Hovinga, T K; Beukhof, J R; Donker, A J.M.; Luyk, W H.J. van; Piers, D A

1984-03-01

A patient is described who had accelerated hypertension and unilateral renal artery stenosis, and who developed further deterioration in renal function during treatment with captopril, an angiotension-I (AI) converting-enzyme inhibitor. sup(99m)Tc-DMSA uptake was greatly diminished in the stenotic kidney, although renal blood flow and handling of /sup 131/I hippurate was preserved. Uptake of sup(99m)Tc-DMSA in the affected kidney returned after substitution of captopril by the vasodilator minoxidil, while a comparable degree of blood pressure control was maintained. This, caution must be taken when interpreting results of sup(99m)Tc-DMSA scintigraphy in patients with proven or suspected renal artery stenosis treated with an AI converting-enzyme inhibiting drug. Moreover, our finding points to the importance of glomerular filtration in the renal handling of /sup 99/Tc-DMSA.

Reversible diminished renal sup(99m)Tc-DMSA uptake during converting-enzyme inhibition in a patient with renal artery stenosis

International Nuclear Information System (INIS)

Kremer Hovinga, T.K.; Beukhof, J.R.; Donker, A.J.M.; Luyk, W.H.J. van; Piers, D.A.

1984-01-01

A patient is described who had accelerated hypertension and unilateral renal artery stenosis, and who developed further deterioration in renal function during treatment with captopril, an angiotension-I (AI) converting-enzyme inhibitor. sup(99m)Tc-DMSA uptake was greatly diminished in the stenotic kidney, although renal blood flow and handling of 131 I hippurate was preserved. Uptake of sup(99m)Tc-DMSA in the affected kidney returned after substitution of captopril by the vasodilator minoxidil, while a comparable degree of blood pressure control was maintained. This, caution must be taken when interpreting results of sup(99m)Tc-DMSA scintigraphy in patients with proven or suspected renal artery stenosis treated with an AI converting-enzyme inhibiting drug. Moreover, our finding points to the importance of glomerular filtration in the renal handling of 99 Tc-DMSA. (orig.)

Peripheral arterial vasodilation hypothesis: a proposal for the initiation of renal sodium and water retention in cirrhosis

DEFF Research Database (Denmark)

Schrier, R W; Arroyo, V; Bernardi, M

1988-01-01

Renal sodium and water retention and plasma volume expansion have been shown to precede ascites formation in experimental cirrhosis. The classical "underfilling" theory, in which ascites formation causes hypovolemia and initiates secondary renal sodium and water retention, thus seems unlikely...... with cirrhosis. Arterial vasodilators and arteriovenous fistula are other examples in which renal sodium and water retention occur secondary to a decreased filling of the arterial vascular tree. An increase in cardiac output and hormonal stimulation are common features of cirrhosis, arteriovenous fistula...... and drug-induced peripheral arterial vasodilation. However, a predilection for the retained sodium and water to transudate into the abdominal cavity occurs with cirrhosis because of the presence of portal hypertension. The Peripheral Arterial Vasodilation Hypothesis also explains the continuum from...

Effect of Yushen zhuyun decoction on rats with diminished ovarian ...

African Journals Online (AJOL)

Purpose: To investigate the effect of Yushen zhuyun decoction (YSZYF) on rats with diminished ovarian reserve (DOR). Methods: High-performance liquid chromatography (HPLC) was used to determine the major phytochemical constituents of YSZYF. Rats with DOR (DOR rats) were prepared by administration of ...

Comparison of vasodilator drug prazosin with digoxin in aortic regurgitation.

Science.gov (United States)

Hockings, B E; Cope, G D; Clarke, G M; Taylor, R R

1980-01-01

Intravenous administration of the vasodilator sodium nitroprusside has beneficial haemodynamic effects in subjects with severe aortic regurgitation while acute digitalisation can produce unwanted effects associated with an increase in systemic vascular resistance. This study compares the haemodynamic effects of the vasodilator prazosin and digoxin in eight patients with isolated severe aortic regurgitation. Prazosin 5 mg orally resulted in a 12 +/- 3 (SE) per cent increase in cardiac index (thermodilution), maintained over four to six hours, while digoxin 0.75 mg intravenously did not change the cardiac index. Prazosin reduced mean arterial pressure by 9 +/- 3 mmHg and systemic vascular resistance by 18 +/- 4 per cent while digoxin resulted in a 6 +/- 2 per cent increase in the latter. Mean pulmonary capillary wedge pressure fell 3 mmHg with prazosin. In this group of patients with severe aortic regurgitation but without severe cardiac failure, the changes with either drug, studied in doses conventionally used, were small but those with prazosin were directionally more desirable than those resulting from digoxin. PMID:7378215

Effect of the Menstrual Cycle on Maximum Oxygen Consumption and Endothelium-Dependent Vasodilation

National Research Council Canada - National Science Library

Andrews, Thomas

1997-01-01

.... We studied endothelium-dependent vasodilation of the brachial artery during three phases of the menstrual cycle in 20 eumenorrheic subjects to determine the effect of endogenous estradiol and progesterone...

[Vasodilative effects of indole alkaloids obtained from domestic plants, Uncaria rhynchophylla Miq. and Amsonia elliptica Roem. et Schult].

Science.gov (United States)

Ozaki, Y

1990-02-01

Vasodilative effects of hirsutine (HS) and hirsuteine (HST) which were isolated from the domestic plant Uncaria rhynchophylla Miq. and beta-yohimbine (beta-Y) which was isolated from the domestic plant Amsonia elliptica Roem. et Schult. were carried out. In the hind-limb artery of anesthetized dogs, intra-arterial administration of HS, HST and beta-Y caused a vasodilatation. The vasodilative potency of HS was somewhat stronger than that of HST, and the potency of both alkaloids was approximately equal to that of papaverine. The vasodilative effect of beta-Y was similar to that of yohimbine, which is considered to be derived from its alpha-adrenoceptor blocking effect, and the potency of both alkaloids was approximately the same, while the effect of beta-Y was stronger than that of papaverine. In the coronary artery, HS showed a vasodilatation and its potency was weaker than that of papaverine. Also, HS showed the same effect in the cerebral artery, and the potency of HS was approximately the same as that of papaverine. These results suggest that the mode of the vasodilative effect induced by HS may partly differ from that of papaverine.

Vasodilator effects of red wines in subcutaneous small resistance artery of patients with essential hypertension.

Science.gov (United States)

Porteri, Enzo; Rizzoni, Damiano; De Ciuceis, Carolina; Boari, Gianluca E M; Platto, Caterina; Pilu, Annamaria; Miclini, Marco; Agabiti Rosei, Claudia; Bulgari, Giuseppe; Agabiti Rosei, Enrico

2010-04-01

It has been suggested that in animal models, red wine may have a protective effect on the vascular endothelium. However, it is not known whether this effect is also present in human small vessels and whether it is specific for certain wines. The objective of this study is to compare the vasodilator effects in subcutaneous small resistance arteries of wines with different flavonoid content as well as of ethanol vs. wines in normotensive (NT) subjects and in patients with essential hypertension (EH). Twenty-six EH and 27 NT were included in the study. Subcutaneous small resistance arteries were dissected and mounted on a micromyograph. Then we evaluated vasodilator responses as concentration-response curves (20, 30, and 50 microl) to the following items: (i) a red wine produced in small oak barrels ("en barrique": EB) (Barolo Oberto 1994), (ii) a red wine produced in large wood barrels (LB) (Barolo Scarzello 1989), (iii) a red wine produced in steel tanks (Albarello Rosso del Salento 1997), and (iv) a white wine produced in steel tanks in the presence or absence of an inhibitor of the nitric oxide (NO) synthase (L-NMMA 100 micromol/l). A dose-dependent vasodilator effect of red wines (particularly EB and LB) was detected in both NT and HT. The observed response was not reduced after preincubation with L-NMMA. Our results suggest red wines are more potent vasodilator than ethanol alone, possibly depending on the content of polyphenols or tannic acid. HT show similar responses compared with NT, indicating that red wine is not harmful in this population.

Exercise-mediated vasodilation in human obesity and metabolic syndrome: effect of acute ascorbic acid infusion.

Science.gov (United States)

Limberg, Jacqueline K; Kellawan, J Mikhail; Harrell, John W; Johansson, Rebecca E; Eldridge, Marlowe W; Proctor, Lester T; Sebranek, Joshua J; Schrage, William G

2014-09-15

We tested the hypothesis that infusion of ascorbic acid (AA), a potent antioxidant, would alter vasodilator responses to exercise in human obesity and metabolic syndrome (MetSyn). Forearm blood flow (FBF, Doppler ultrasound) was measured in lean, obese, and MetSyn adults (n = 39, 32 ± 2 yr). A brachial artery catheter was inserted for blood pressure monitoring and local infusion of AA. FBF was measured during dynamic handgrip exercise (15% maximal effort) with and without AA infusion. To account for group differences in blood pressure and forearm size, and to assess vasodilation, forearm vascular conductance (FVC = FBF/mean arterial blood pressure/lean forearm mass) was calculated. We examined the time to achieve steady-state FVC (mean response time, MRT) and the rise in FVC from rest to steady-state exercise (Δ, exercise - rest) before and during acute AA infusion. The MRT (P = 0.26) and steady-state vasodilator responses to exercise (ΔFVC, P = 0.31) were not different between groups. Intra-arterial infusion of AA resulted in a significant increase in plasma total antioxidant capacity (174 ± 37%). AA infusion did not alter MRT or steady-state FVC in any group (P = 0.90 and P = 0.85, respectively). Interestingly, higher levels of C-reactive protein predicted longer MRT (r = 0.52, P exercise does not alter the time course or magnitude of exercise-mediated vasodilation in groups of young lean, obese, or MetSyn adults. However, systemic inflammation may limit the MRT to exercise, which can be improved with AA. Copyright © 2014 the American Physiological Society.

Dietary nitrate restores compensatory vasodilation and exercise capacity in response to a compromise in oxygen delivery in the noncompensator phenotype.

Science.gov (United States)

Bentley, Robert F; Walsh, Jeremy J; Drouin, Patrick J; Velickovic, Aleksandra; Kitner, Sarah J; Fenuta, Alyssa M; Tschakovsky, Michael E

2017-09-01

Recently, dietary nitrate supplementation has been shown to improve exercise capacity in healthy individuals through a potential nitrate-nitrite-nitric oxide pathway. Nitric oxide has been shown to play an important role in compensatory vasodilation during exercise under hypoperfusion. Previously, we established that certain individuals lack a vasodilation response when perfusion pressure reductions compromise exercising muscle blood flow. Whether this lack of compensatory vasodilation in healthy, young individuals can be restored with dietary nitrate supplementation is unknown. Six healthy (21 ± 2 yr), recreationally active men completed a rhythmic forearm exercise. During steady-state exercise, the exercising arm was rapidly transitioned from an uncompromised (below heart) to a compromised (above heart) position, resulting in a reduction in local pressure of -31 ± 1 mmHg. Exercise was completed following 5 days of nitrate-rich (70 ml, 0.4 g nitrate) and nitrate-depleted (70 ml, ~0 g nitrate) beetroot juice consumption. Forearm blood flow (in milliliters per minute; brachial artery Doppler and echo ultrasound), mean arterial blood pressure (in millimeters of mercury; finger photoplethysmography), exercising forearm venous effluent (ante-cubital vein catheter), and plasma nitrite concentrations (chemiluminescence) revealed two distinct vasodilatory responses: nitrate supplementation increased (plasma nitrite) compared with placebo (245 ± 60 vs. 39 ± 9 nmol/l; P nitrate supplementation (568 ± 117 vs. 714 ± 139 ml ⋅ min -1 ⋅ 100 mmHg -1 ; P = 0.005) but not in placebo (687 ± 166 vs. 697 ± 171 min -1 ⋅ 100 mmHg -1 ; P = 0.42). As such, peak exercise capacity was reduced to a lesser degree (-4 ± 39 vs. -39 ± 27 N; P = 0.01). In conclusion, dietary nitrate supplementation during a perfusion pressure challenge is an effective means of restoring exercise capacity and enabling compensatory vasodilation. NEW & NOTEWORTHY Previously, we

In vivo comparative study of ocular vasodilation, a relative indicator of hyperemia, in guinea pigs following treatment with bimatoprost ophthalmic solutions 0.01% and 0.03%

Directory of Open Access Journals (Sweden)

Abayomi B Ogundele

2010-06-01

Full Text Available Abayomi B Ogundele, David Earnest, Marsha A McLaughlinAlcon Research, Limited, Fort Worth, TX, USAObjective: The objective of this in vivo study was to compare the incidence of vasodilation in guinea pigs following topical administration of bimatoprost ophthalmic solutions 0.01% and 0.03%.Methods: The study comprised 20 guinea pigs assigned to 2 treatment groups (10 per treatment group to receive either bimatoprost 0.01% or bimatoprost 0.03%. Animals were hand-held under 2.75 × magnification to score ocular vasodilation (a measure of hyperemia, using a scoring system developed at Alcon Research, Ltd. Following baseline ocular scoring, each animal received a 30 μL dose to the left eye of either bimatoprost 0.01% (3 μg or bimatoprost 0.03% (9 μg. Vasodilation was again scored at 1, 2, 3, 4, 5 and 6 hours after dosing. Incidence of vasodilation was calculated as the percent of total eyes in each 2-hour time interval with scores ≥2.Results: The incidence of vasodilation was higher in the bimatoprost 0.01% treatment group (range, 45.0% to 60.0% than the bimatoprost 0.03% treatment group (range, 30.0% to 52.2% at all post-dosing time points.Conclusion: The 2 bimatoprost formulations elicited ocular vasodilation of long duration (>6 hours in the guinea pig model, with the bimatoprost 0.01% treatment group showing a higher incidence of ocular vasodilation than the bimatoprost 0.03% treatment group. Further clinical studies would be needed to determine whether the higher incidence of vasodilation may also be attributed to the increased BAK concentration in the bimatoprost 0.01% formulation.Keywords: bitamoprost, ocular vasodilation, hyperemia

Lipid Emulsion Inhibits Vasodilation Induced by a Toxic Dose of Bupivacaine via Attenuated Dephosphorylation of Myosin Phosphatase Target Subunit 1 in Isolated Rat Aorta

Science.gov (United States)

Ok, Seong-Ho; Byon, Hyo-Jin; Kwon, Seong-Chun; Park, Jungchul; Lee, Youngju; Hwang, Yeran; Baik, Jiseok; Choi, Mun-Jeoung; Sohn, Ju-Tae

2015-01-01

Lipid emulsions are widely used for the treatment of systemic toxicity that arises from local anesthetics. The goal of this in vitro study was to examine the cellular mechanism associated with the lipid emulsion-mediated attenuation of vasodilation induced by a toxic dose of bupivacaine in isolated endothelium-denuded rat aorta. The effects of lipid emulsion on vasodilation induced by bupivacaine, mepivacaine, and verapamil were assessed in isolated aorta precontracted with phenylephrine, the Rho kinase stimulant NaF, and the protein kinase C activator phorbol 12,13-dibutyrate (PDBu). The effects of Rho kinase inhibitor Y-27632 on contraction induced by phenylephrine or NaF were assessed. The effects of bupivacaine on intracellular calcium concentrations ([Ca2+]i) and tension induced by NaF were simultaneously measured. The effects of bupivacaine alone and lipid emulsion plus bupivacaine on myosin phosphatase target subunit 1 (MYPT1) phosphorylation induced by NaF were examined in rat aortic vascular smooth muscle cells. In precontracted aorta, the lipid emulsion attenuated bupivacaine-induced vasodilation but had no effect on mepivacaine-induced vasodilation. Y-27632 attenuated contraction induced by either phenylephrine or NaF. The lipid emulsion attenuated verapamil-induced vasodilation. Compared with phenylephrine-induced precontracted aorta, bupivacaine-induced vasodilation was slightly attenuated in NaF-induced precontracted aorta. The magnitude of the bupivacaine-induced vasodilation was higher than that of a bupivacaine-induced decrease in [Ca2+]i. Bupivacaine attenuated NaF-induced MYPT1 phosphorylation, whereas lipid emulsion pretreatment attenuated the bupivacaine-induced inhibition of MYPT1 phosphorylation induced by NaF. Taken together, these results suggest that lipid emulsions attenuate bupivacaine-induced vasodilation via the attenuation of inhibition of MYPT1 phosphorylation evoked by NaF. PMID:26664257

Wearing graduated compression stockings augments cutaneous vasodilation but not sweating during exercise in the heat.

Science.gov (United States)

Fujii, Naoto; Nikawa, Toshiya; Tsuji, Bun; Kenny, Glen P; Kondo, Narihiko; Nishiyasu, Takeshi

2017-05-01

The activation of cutaneous vasodilation and sweating are essential to the regulation of core temperature during exercise in the heat. We assessed the effect of graduated compression induced by wearing stockings on cutaneous vasodilation and sweating during exercise in the heat (30°C). On two separate occasions, nine young males exercised for 45 min or until core temperature reached ~1.5°C above baseline resting while wearing either (1) stockings causing graduated compression (graduate compression stockings, GCS), or (2) loose-fitting stockings without compression (Control). Forearm vascular conductance was evaluated by forearm blood flow (venous occlusion plethysmography) divided by mean arterial pressure to estimate cutaneous vasodilation. Sweat rate was estimated using the ventilated capsule technique. Core and skin temperatures were measured continuously. Exercise duration was similar between conditions (Control: 42.2 ± 3.6 min vs. GCS: 42.2 ± 3.6 min, P  = 1.00). Relative to Control, GCS increased forearm vascular conductance during the late stages (≥30 min) of exercise (e.g., at 40 min, 15.6 ± 5.6 vs. 18.0 ± 6.0 units, P  = 0.01). This was paralleled by a greater sensitivity (23.1 ± 9.1 vs. 32.1 ± 15.0 units°C -1 , P  = 0.043) and peak level (14.1 ± 5.1 vs. 16.3 ± 5.7 units, P  = 0.048) of cutaneous vasodilation as evaluated from the relationship between forearm vascular conductance with core temperature. However, the core temperature threshold at which an increase in forearm vascular conductance occurred did not differ between conditions (Control: 36.9 ± 0.2 vs. GCS: 37.0 ± 0.3°C, P  = 0.13). In contrast, no effect of GCS on sweating was measured (all P  > 0.05). We show that the use of GCS during exercise in the heat enhances cutaneous vasodilation and not sweating. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American

Correlative intravital imaging of cGMP signals and vasodilation in mice

Directory of Open Access Journals (Sweden)

Martin eThunemann

2014-10-01

Full Text Available Cyclic guanosine monophosphate (cGMP is an important signaling molecule and drug target in the cardiovascular system. It is well known that stimulation of the vascular nitric oxide (NO-cGMP pathway results in vasodilation. However, the spatiotemporal dynamics of cGMP signals themselves and the cGMP concentrations within specific cardiovascular cell types in health, disease, and during pharmacotherapy with cGMP-elevating drugs are largely unknown. To facilitate the analysis of cGMP signaling in vivo, we have generated transgenic mice that express fluorescence resonance energy transfer (FRET-based cGMP sensor proteins. Here, we describe two models of intravital FRET/cGMP imaging in the vasculature of cGMP sensor mice: (1 epifluorescence-based ratio imaging in resistance-type vessels of the cremaster muscle and (2 ratio imaging by multiphoton microscopy within the walls of subcutaneous blood vessels accessed through a dorsal skinfold chamber. Both methods allow simultaneous monitoring of NO-induced cGMP transients and vasodilation in living mice. Detailed protocols of all steps necessary to perform and evaluate intravital imaging experiments of the vasculature of anesthetized mice including surgery, imaging, and data evaluation are provided. An image segmentation approach is described to estimate FRET/cGMP changes within moving structures such as the vessel wall during vasodilation. The methods presented herein should be useful to visualize cGMP or other biochemical signals that are detectable with FRET-based biosensors, such as cyclic adenosine monophosphate or Ca2+, and to correlate them with respective vascular responses. With further refinement and combination of transgenic mouse models and intravital imaging technologies, we envision an exciting future, in which we are able to ‘watch’ biochemistry, (patho physiology, and pharmacotherapy in the context of a living mammalian organism.

Quantitative relationship between coronary calcium content and coronary flow reserve as assessed by integrated PET/CT imaging

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Curillova, Zelmira [Brigham and Women' s Hospital, Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Boston, MA (United States); VA Boston Healthcare System, Division of Cardiology, Department of Medicine, West Roxbury, MA (United States); Yaman, Bettina F.; Sitek, Arkadius; El Fakhri, Georges [Brigham and Women' s Hospital, Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Boston, MA (United States); Dorbala, Sharmila [Brigham and Women' s Hospital, Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Boston, MA (United States); Brigham and Women' s Hospital, Noninvasive Cardiovascular Imaging Program, Departments of Medicine (Cardiology) and Radiology, Boston, MA (United States); Kwong, Raymond Y. [Harvard Medical School, Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women' s Hospital, Boston, MA (United States); Brigham and Women' s Hospital, Noninvasive Cardiovascular Imaging Program, Departments of Medicine (Cardiology) and Radiology, Boston, MA (United States); Anagnostopoulos, Constantinos [Brigham and Women' s Hospital, Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Boston, MA (United States); Royal Brompton Hospital, Department of Nuclear Medicine, London (United Kingdom); Di Carli, Marcelo F. [Brigham and Women' s Hospital, Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Boston, MA (United States); Harvard Medical School, Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women' s Hospital, Boston, MA (United States); Brigham and Women' s Hospital, Noninvasive Cardiovascular Imaging Program, Departments of Medicine (Cardiology) and Radiology, Boston, MA (United States); Brigham and Women' s Hospital, Division of Nuclear Medicine and Molecular Imaging, Boston, MA (United States)

2009-10-15

To evaluate the relationship between coronary artery calcium (CAC) and coronary vasodilator function. We evaluated 136 patients without known coronary artery disease (CAD) undergoing vasodilator stress {sup 82}Rb PET/CT and CAC scoring who showed normal myocardial perfusion. The CAC score, resting and hyperemic myocardial blood flow (MBF), coronary flow reserve (CFR) and coronary vascular resistance were analyzed. Global and regional CAC scores showed significant but weak inverse correlations with hyperemic MBF (r=-0.31 and r=-0.26, p{<=}0.0002 respectively) and CFR (r=-0.28 and r=-0.2, p{<=}0.001 respectively). With increasing CAC score, there was a modest stepwise decline in CFR on a per-patient basis (1.8{+-}0.5 vs 1.7{+-}0.5 vs 1.5{+-}0.4, p=0.048, with total CAC=0, 1-400 and >400, respectively) and on a per-vessel basis. In multivariable modeling only body mass index and CAC score were predictive of CFR. In patients with an intermediate likelihood of, but without overt, CAD, there is a statistically significant but weak inverse correlation between CAC content and coronary vasodilator function. The strength of this association weakens after adjusting CAC scores for age, gender and coronary risk factors. This suggests that CAC and coronary vasodilator function provide biologically different information regarding atherosclerosis. (orig.)

Quantitative relationship between coronary calcium content and coronary flow reserve as assessed by integrated PET/CT imaging

International Nuclear Information System (INIS)

Curillova, Zelmira; Yaman, Bettina F.; Sitek, Arkadius; El Fakhri, Georges; Dorbala, Sharmila; Kwong, Raymond Y.; Anagnostopoulos, Constantinos; Di Carli, Marcelo F.

2009-01-01

To evaluate the relationship between coronary artery calcium (CAC) and coronary vasodilator function. We evaluated 136 patients without known coronary artery disease (CAD) undergoing vasodilator stress 82 Rb PET/CT and CAC scoring who showed normal myocardial perfusion. The CAC score, resting and hyperemic myocardial blood flow (MBF), coronary flow reserve (CFR) and coronary vascular resistance were analyzed. Global and regional CAC scores showed significant but weak inverse correlations with hyperemic MBF (r=-0.31 and r=-0.26, p≤0.0002 respectively) and CFR (r=-0.28 and r=-0.2, p≤0.001 respectively). With increasing CAC score, there was a modest stepwise decline in CFR on a per-patient basis (1.8±0.5 vs 1.7±0.5 vs 1.5±0.4, p=0.048, with total CAC=0, 1-400 and >400, respectively) and on a per-vessel basis. In multivariable modeling only body mass index and CAC score were predictive of CFR. In patients with an intermediate likelihood of, but without overt, CAD, there is a statistically significant but weak inverse correlation between CAC content and coronary vasodilator function. The strength of this association weakens after adjusting CAC scores for age, gender and coronary risk factors. This suggests that CAC and coronary vasodilator function provide biologically different information regarding atherosclerosis. (orig.)

Modulatory Effect of 2-(4-Hydroxyphenylamino-1,4-naphthoquinone on Endothelial Vasodilation in Rat Aorta

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Javier Palacios

2016-01-01

Full Text Available The vascular endothelium plays an essential role in the control of the blood flow. Pharmacological agents like quinone (menadione at various doses modulate this process in a variety of ways. In this study, Q7, a 2-phenylamino-1,4-naphthoquinone derivative, significantly increased oxidative stress and induced vascular dysfunction at concentrations that were not cytotoxic to endothelial or vascular smooth muscle cells. Q7 reduced nitric oxide (NO levels and endothelial vasodilation to acetylcholine in rat aorta. It also blunted the calcium release from intracellular stores by increasing the phenylephrine-induced vasoconstriction when CaCl2 was added to a calcium-free medium but did not affect the influx of calcium from extracellular space. Q7 increased the vasoconstriction to BaCl2 (10−3 M, an inward rectifying K+ channels blocker, and blocked the vasodilation to KCl (10−2 M in aortic rings precontracted with BaCl2. This was recovered with sodium nitroprusside (10−8 M, a NO donor. In conclusion, Q7 induced vasoconstriction was through a modulation of cellular mechanisms involving calcium fluxes through K+ channels, and oxidative stress induced endothelium damage. These findings contribute to the characterization of new quinone derivatives with low cytotoxicity able to pharmacologically modulate vasodilation.

Tapping but not massage enhances vasodilation and improves venous palpation of cutaneous veins.

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Ichimura, Mika; Sasaki, Shinsuke; Mori, Masaharu; Ogino, Tetsuya

2015-01-01

This paper investigated whether tapping on the median cubital vein or massaging the forearm was more effective in obtaining better venous palpation for venipuncture. Forty healthy volunteers in their twenties were subjected to tapping (10 times in 5 sec) or massage (10 strokes in 20 sec from the wrist to the cubital fossa) under tourniquet inflation on the upper arm. Venous palpation was assessed using the venous palpation score (0-6, with 0 being impalpable). Three venous factors-venous depth, cross-sectional area, and elevation-were also measured using ultrasonography. The venous palpation score increased significantly by tapping but not by massage. Moreover, all 3 venous measurements changed significantly by tapping, while only the depth decreased significantly by massage. The three venous measurements correlated significantly with the venous palpation score, indicating that they are useful objective indicators for evaluating vasodilation. We suggest that tapping is an effective vasodilation technique.

PI3K/Akt-independent NOS/HO activation accounts for the facilitatory effect of nicotine on acetylcholine renal vasodilations: modulation by ovarian hormones.

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Eman Y Gohar

Full Text Available We investigated the effect of chronic nicotine on cholinergically-mediated renal vasodilations in female rats and its modulation by the nitric oxide synthase (NOS/heme oxygenase (HO pathways. Dose-vasodilatory response curves of acetylcholine (0.01-2.43 nmol were established in isolated phenylephrine-preconstricted perfused kidneys obtained from rats treated with or without nicotine (0.5-4.0 mg/kg/day, 2 weeks. Acetylcholine vasodilations were potentiated by low nicotine doses (0.5 and 1 mg/kg/day in contrast to no effect for higher doses (2 and 4 mg/kg/day. The facilitatory effect of nicotine was acetylcholine specific because it was not observed with other vasodilators such as 5'-N-ethylcarboxamidoadenosine (NECA, adenosine receptor agonist or papaverine. Increases in NOS and HO-1 activities appear to mediate the nicotine-evoked enhancement of acetylcholine vasodilation because the latter was compromised after pharmacologic inhibition of NOS (L-NAME or HO-1 (zinc protoporphyrin, ZnPP. The renal protein expression of phosphorylated Akt was not affected by nicotine. We also show that the presence of the two ovarian hormones is necessary for the nicotine augmentation of acetylcholine vasodilations to manifest because nicotine facilitation was lost in kidneys of ovariectomized (OVX and restored after combined, but not individual, supplementation with medroxyprogesterone acetate (MPA and estrogen (E2. Together, the data suggests that chronic nicotine potentiates acetylcholine renal vasodilation in female rats via, at least partly, Akt-independent HO-1 upregulation. The facilitatory effect of nicotine is dose dependent and requires the presence of the two ovarian hormones.

Modulatory Effect of 2-(4-Hydroxyphenyl)amino-1,4-naphthoquinone on Endothelial Vasodilation in Rat Aorta.

Science.gov (United States)

Palacios, Javier; Cifuentes, Fredi; Valderrama, Jaime A; Benites, Julio; Ríos, David; González, Constanza; Chiong, Mario; Cartes-Saavedra, Benjamín; Lafourcade, Carlos; Wyneken, Ursula; González, Pamela; Owen, Gareth I; Pardo, Fabián; Sobrevia, Luis; Buc Calderon, Pedro

The vascular endothelium plays an essential role in the control of the blood flow. Pharmacological agents like quinone (menadione) at various doses modulate this process in a variety of ways. In this study, Q7 , a 2-phenylamino-1,4-naphthoquinone derivative, significantly increased oxidative stress and induced vascular dysfunction at concentrations that were not cytotoxic to endothelial or vascular smooth muscle cells. Q7 reduced nitric oxide (NO) levels and endothelial vasodilation to acetylcholine in rat aorta. It also blunted the calcium release from intracellular stores by increasing the phenylephrine-induced vasoconstriction when CaCl 2 was added to a calcium-free medium but did not affect the influx of calcium from extracellular space. Q7 increased the vasoconstriction to BaCl 2 (10 -3  M), an inward rectifying K + channels blocker, and blocked the vasodilation to KCl (10 -2  M) in aortic rings precontracted with BaCl 2 . This was recovered with sodium nitroprusside (10 -8  M), a NO donor. In conclusion, Q7 induced vasoconstriction was through a modulation of cellular mechanisms involving calcium fluxes through K + channels, and oxidative stress induced endothelium damage. These findings contribute to the characterization of new quinone derivatives with low cytotoxicity able to pharmacologically modulate vasodilation.

Voluntary wheel running selectively augments insulin-stimulated vasodilation in arterioles from white skeletal muscle of insulin-resistant rats.

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Mikus, Catherine R; Roseguini, Bruno T; Uptergrove, Grace M; Morris, E Matthew; Rector, Randy Scott; Libla, Jessica L; Oberlin, Douglas J; Borengasser, Sarah J; Taylor, Angelina M; Ibdah, Jamal A; Laughlin, Maurice Harold; Thyfault, John P

2012-11-01

Exercise (RUN) prevents declines in insulin-mediated vasodilation, an important component of insulin-mediated glucose disposal, in rats prone to obesity and insulin resistance. Determine whether RUN (1) improves insulin-stimulated vasodilation after insulin resistance has been established, and (2) differentially affects arterioles from red and white muscle. Insulin signaling and vasoreactivity to insulin (1-1000 μIU/mL) were assessed in 2A from the Gw and Gr of SED OLETF rats at 12 and 20 weeks of age (SED12, SED20) and those undergoing RUN (RUN20) or caloric restriction (CR20; to match body weight of RUN) from 12 to 20 weeks. Glucose and insulin responses to i.p. glucose were reduced in RUN20, elevated in SED20 (p RUN20 (p RUN selectively improved insulin-mediated vasodilation in Gw 2As, in part through attenuated ET-1 sensitivity/production, an adaptation that was independent of changes in adiposity and may contribute to enhanced insulin-stimulated glucose disposal. © 2012 John Wiley & Sons Ltd.

The association of neurocognitive impairment with diminished expression and apathy in schizophrenia.

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Hartmann-Riemer, Matthias N; Hager, Oliver M; Kirschner, Matthias; Bischof, Martin; Kluge, Agne; Seifritz, Erich; Kaiser, Stefan

2015-12-01

Negative symptoms can be grouped into the two dimensions of diminished expression and apathy, which have been shown to be dissociable regarding external validators, such as functional outcome. Here, we investigated whether these two dimensions differentially relate to neurocognitive impairment in schizophrenia. 47 patients with schizophrenia or schizoaffective disorder and 33 healthy control participants were subjected to a neurocognitive test battery assessing multiple cognitive domains (processing speed, working memory, verbal fluency, verbal learning and memory, mental planning), which are integrated into a composite cognition score. Negative symptoms in patients were assessed using the Brief Negative Symptom Scale. We found that diminished expression significantly related to neurocognitive impairment, while severity of apathy symptoms was not directly associated with neurocognition. Other assessed clinical variables include chlorpromazine equivalents, positive symptoms, and depressive symptoms and did not influence the results. Our results are in line with a cognitive resource limitation model of diminished expression in schizophrenia and indicate that cognitive remediation therapy might be helpful to ameliorate expressive deficits. Copyright © 2015 Elsevier B.V. All rights reserved.

Does PGE₁ vasodilator prevent orthopaedic implant-related infection in diabetes? Preliminary results in a mouse model.

Science.gov (United States)

Lovati, Arianna B; Romanò, Carlo L; Monti, Lorenzo; Vassena, Christian; Previdi, Sara; Drago, Lorenzo

2014-01-01

Implant-related infections are characterized by bacterial colonization and biofilm formation on the prosthesis. Diabetes represents one of the risk factors that increase the chances of prosthetic infections because of related severe peripheral vascular disease. Vasodilatation can be a therapeutic option to overcome diabetic vascular damages and increase the local blood supply. In this study, the effect of a PGE₁ vasodilator on the incidence of surgical infections in diabetic mice was investigated. A S. aureus implant-related infection was induced in femurs of diabetic mice, then differently treated with a third generation cephalosporin alone or associated with a PGE₁ vasodilator. Variations in mouse body weight were evaluated as index of animal welfare. The femurs were harvested after 28 days and underwent both qualitative and quantitative analysis as micro-CT, histological and microbiological analyses. The analysis performed in this study demonstrated the increased host response to implant-related infection in diabetic mice treated with the combination of a PGE₁ and antibiotic. In this group, restrained signs of infections were identified by micro-CT and histological analysis. On the other hand, the diabetic mice treated with the antibiotic alone showed a severe infection and inability to successfully respond to the standard antimicrobial treatment. The present study revealed interesting preliminary results in the use of a drug combination of antibiotic and vasodilator to prevent implant-related Staphylococcus aureus infections in a diabetic mouse model.

Vasodilation increases pulse pressure variation, mimicking hypovolemic status in rabbits

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Glauco A Westphal

2010-01-01

Full Text Available OBJECTIVE: To test the hypothesis that pulse pressure respiratory variation (PPV amplification, observed in hypovolemia, can also be observed during sodium nitroprusside (SNP-induced vasodilation. INTRODUCTION: PPV is largely used for early identification of cardiac responsiveness, especially when hypovolemia is suspected. PPV results from respiratory variation in transpulmonary blood flow and reflects the left ventricular preload variations during respiratory cycles. Any factor that decreases left ventricular preload can be associated with PPV amplification, as seen in hypovolemia. METHODS: Ten anesthetized and mechanically ventilated rabbits underwent progressive hypotension by either controlled hemorrhage (Group 1 or intravenous SNP infusion (Group 2. Animals in Group 1 (n = 5 had graded hemorrhage induced at 10% steps until 50% of the total volume was bled. Mean arterial pressure (MAP steps were registered and assumed as pressure targets to be reached in Group 2. Group 2 (n = 5 was subjected to a progressive SNP infusion to reach similar pressure targets as those defined in Group 1. Heart rate (HR, systolic pressure variation (SPV and PPV were measured at each MAP step, and the values were compared between the groups. RESULTS: SPV and PPV were similar between the experimental models in all steps (p > 0.16. SPV increased earlier in Group 2. CONCLUSION: Both pharmacologic vasodilation and graded hemorrhage induced PPV amplification similar to that observed in hypovolemia, reinforcing the idea that amplified arterial pressure variation does not necessarily represent hypovolemic status but rather potential cardiovascular responsiveness to fluid infusion.

Oscillatory dynamics of vasoconstriction and vasodilation identified by time-localized phase coherence

International Nuclear Information System (INIS)

Sheppard, L W; McClintock, P V E; Stefanovska, A; Vuksanovic, V

2011-01-01

We apply wavelet-based time-localized phase coherence to investigate the relationship between blood flow and skin temperature, and between blood flow and instantaneous heart rate (IHR), during vasoconstriction and vasodilation provoked by local cooling or heating of the skin. A temperature-controlled metal plate (∼10 cm 2 ) placed on the volar side of the left arm was used to provide the heating and cooling. Beneath the plate, the blood flow was measured by laser Doppler flowmetry and the adjacent skin temperature by a thermistor. Two 1 h datasets were collected from each of the ten subjects. In each case a 30 min basal recording was followed by a step change in plate temperature, to either 24 deg. C or 42 deg. C. The IHR was derived from simultaneously recorded ECG. We confirm the changes in the energy and frequency of blood flow oscillations during cooling and heating reported earlier. That is, during cooling, there was a significant decrease in the average frequency of myogenic blood flow oscillations (p < 0.05) and the myogenic spectral peak became more prominent. During heating, there was a significant (p < 0.05) general increase in spectral energy, associated with vasodilation, except in the myogenic interval. Weak phase coherence between temperature and blood flow was observed for unperturbed skin, but it increased in all frequency intervals as a result of heating. It was not significantly affected by cooling. We also show that significant (p < 0.05) phase coherence exists between blood flow and IHR in the respiratory and myogenic frequency intervals. Cooling did not affect this phase coherence in any of the frequency intervals, whereas heating enhanced the phase coherence in the respiratory and myogenic intervals. This can be explained by the reduction in vascular resistance produced by heating, a process where myogenic mechanisms play a key role. We conclude that the mechanisms of vasodilation and vasoconstriction, in response to temperature change, are

Vasodilators in the treatment of acute heart failure : what we know, what we don't

NARCIS (Netherlands)

Metra, Marco; Teerlink, John R.; Voors, Adriaan A.; Felker, G. Michael; Milo-Cotter, Olga; Weatherley, Beth; Dittrich, Howard; Cotter, Gad

2009-01-01

Although we have recently witnessed substantial progress in management and outcome of patients with chronic heart failure, acute heart failure (AHF) management and outcome have not changed over almost a generation. Vasodilators are one of the cornerstones of AHF management; however, to a large

Hydralazine-induced vasodilation involves opening of high conductance Ca2+-activated K+ channels

DEFF Research Database (Denmark)

Bang, Lone; Nielsen-Kudsk, J E; Gruhn, N

1998-01-01

The purpose of this study was to investigate whether high conductance Ca2+-activated K+ channels (BK(Ca)) are mediating the vasodilator action of hydralazine. In isolated porcine coronary arteries, hydralazine (1-300 microM), like the K+ channel opener levcromakalim, preferentially relaxed......M) suppressed this response by 82% (P opening of BK(Ca) takes part in the mechanism whereby...

Decreased active vasodilator sensitivity in aged skin.

Science.gov (United States)

Kenney, W L; Morgan, A L; Farquhar, W B; Brooks, E M; Pierzga, J M; Derr, J A

1997-04-01

Older men and women respond to local and reflex-mediated heat stress with an attenuated increase in cutaneous vascular conductance (CVC). This study was performed to test the hypothesis that an augmented or sustained noradrenergic vasoconstriction (VC) may play a role in this age-related difference. Fifteen young (22 +/- 1 yr) and 15 older (66 +/- 1 yr) men exercised at 50% peak oxygen uptake in a 36 degrees C environment. Skin perfusion was monitored at two sites on the right forearm by laser-Doppler flowmetry: one site pretreated with bretylium tosylate (BT) to block the local release of norepinephrine and thus VC and an adjacent control site. Blockade of reflex VC was verified during whole body cooling using a water-perfused suit. CVC (perfusion divided by mean arterial pressure) at each site was reported as a percentage of the maximal CVC (%CVCmax) induced at the end of each experiment by prolonged local heating at 42 degrees C. Neither age nor BT affected the %CVCmax (75-86%) attained at high core temperatures. During the early rise phase of CVC, the %CVCmax-change in esophageal temperature (delta T(es)) curve was shifted to the right in the older men (effective delta T(es) associated with 50% CVC response for young, 0.22 +/- 0.04 and 0.39 +/- 0.04 degrees C and for older, 0.73 +/- 0.04 and 0.85 +/- 0.04 degrees C at control and BT sites, respectively). BT had no interactive effect on this age difference, suggesting a lack of involvement of the VC system in the attenuated CVC response of individuals over the age of 60 yr. Additionally, increases in skin vascular conductance were quantitatively compared by measuring increases in total forearm vascular conductance (FVC, restricted to the forearm skin under these conditions). After the initial approximately 0.2 degrees C increase in T(es), FVC was 40-50% lower in the older men (P < 0.01) for the remainder of the exercise. Decreased active vasodilator sensitivity to increasing core temperature, coupled with

Does PGE₁ vasodilator prevent orthopaedic implant-related infection in diabetes? Preliminary results in a mouse model.

Directory of Open Access Journals (Sweden)

Arianna B Lovati

Full Text Available BACKGROUND: Implant-related infections are characterized by bacterial colonization and biofilm formation on the prosthesis. Diabetes represents one of the risk factors that increase the chances of prosthetic infections because of related severe peripheral vascular disease. Vasodilatation can be a therapeutic option to overcome diabetic vascular damages and increase the local blood supply. In this study, the effect of a PGE₁ vasodilator on the incidence of surgical infections in diabetic mice was investigated. METHODOLOGY: A S. aureus implant-related infection was induced in femurs of diabetic mice, then differently treated with a third generation cephalosporin alone or associated with a PGE₁ vasodilator. Variations in mouse body weight were evaluated as index of animal welfare. The femurs were harvested after 28 days and underwent both qualitative and quantitative analysis as micro-CT, histological and microbiological analyses. RESULTS: The analysis performed in this study demonstrated the increased host response to implant-related infection in diabetic mice treated with the combination of a PGE₁ and antibiotic. In this group, restrained signs of infections were identified by micro-CT and histological analysis. On the other hand, the diabetic mice treated with the antibiotic alone showed a severe infection and inability to successfully respond to the standard antimicrobial treatment. CONCLUSIONS: The present study revealed interesting preliminary results in the use of a drug combination of antibiotic and vasodilator to prevent implant-related Staphylococcus aureus infections in a diabetic mouse model.

Resveratrol induces acute endothelium-dependent renal vasodilation mediated through nitric oxide and reactive oxygen species scavenging

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Gordish, Kevin L.

2014-01-01

Resveratrol is suggested to have beneficial cardiovascular and renoprotective effects. Resveratrol increases endothelial nitric oxide synthase (eNOS) expression and nitric oxide (NO) synthesis. We hypothesized resveratrol acts as an acute renal vasodilator, mediated through increased NO production and scavenging of reactive oxygen species (ROS). In anesthetized rats, we found 5.0 mg/kg body weight (bw) of resveratrol increased renal blood flow (RBF) by 8% [from 6.98 ± 0.42 to 7.54 ± 0.17 ml·min−1·gram of kidney weight−1 (gkw); n = 8; P resveratrol before and after 10 mg/kg bw of the NOS inhibitor N-nitro-l-arginine methyl ester (l-NAME). l-NAME reduced the increase in RBF to resveratrol by 54% (from 0.59 ± 0.05 to 0.27 ± 0.06 ml·min−1·gkw−1; n = 10; P resveratrol before and after 1 mg/kg bw tempol, a superoxide dismutase mimetic. Resveratrol increased RBF 7.6% (from 5.91 ± 0.32 to 6.36 ± 0.12 ml·min−1·gkw−1; n = 7; P resveratrol-induced increase in RBF (from 0.45 ± 0.12 to 0.10 ± 0.05 ml·min−1·gkw−1; n = 7; P Resveratrol-induced vasodilation remained unaffected. We conclude intravenous resveratrol acts as an acute renal vasodilator, partially mediated by increased NO production/NO bioavailability and superoxide scavenging but not by inducing vasodilatory cyclooxygenase products. PMID:24431202

Effect of skin temperature on cutaneous vasodilator response to the β-adrenergic agonist isoproterenol.

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Hodges, Gary J; Kellogg, Dean L; Johnson, John M

2015-04-01

The vascular response to local skin cooling is dependent in part on a cold-induced translocation of α2C-receptors and an increased α-adrenoreceptor function. To discover whether β-adrenergic function might contribute, we examined whether β-receptor sensitivity to the β-agonist isoproterenol was affected by local skin temperature. In seven healthy volunteers, skin blood flow was measured from the forearm by laser-Doppler flowmetry and blood pressure was measured by finger photoplethysmography. Data were expressed as cutaneous vascular conductance (CVC; laser-Doppler flux/mean arterial blood pressure). Pharmacological agents were administered via intradermal microdialysis. We prepared four skin sites: one site was maintained at a thermoneutral temperature of 34°C (32 ± 10%CVCmax) one site was heated to 39°C (38 ± 11%CVCmax); and two sites were cooled, one to 29°C (22 ± 7%CVCmax) and the other 24°C (16 ± 4%CVCmax). After 20 min at these temperatures to allow stabilization of skin blood flow, isoproterenol was perfused in concentrations of 10, 30, 100, and 300 μM. Each concentration was perfused for 15 min. Relative to the CVC responses to isoproterenol at the thermoneutral skin temperature (34°C) (+21 ± 10%max), low skin temperatures reduced (at 29°C) (+17 ± 6%max) or abolished (at 24°C) (+1 ± 5%max) the vasodilator response, and warm (39°C) skin temperatures enhanced the vasodilator response (+40 ± 9%max) to isoproterenol. These data indicate that β-adrenergic function was influenced by local skin temperature. This finding raises the possibility that a part of the vasoconstrictor response to direct skin cooling could include reduced background β-receptor mediated vasodilation. Copyright © 2015 the American Physiological Society.

Candesartan restores pressure-induced vasodilation and prevents skin pressure ulcer formation in diabetic mice.

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Danigo, Aurore; Nasser, Mohamad; Bessaguet, Flavien; Javellaud, James; Oudart, Nicole; Achard, Jean-Michel; Demiot, Claire

2015-02-18

Angiotensin II type 1 receptor (AT1R) blockers have beneficial effects on neurovascular complications in diabetes and in organ's protection against ischemic episodes. The present study examines whether the AT1R blocker candesartan (1) has a beneficial effect on diabetes-induced alteration of pressure-induced vasodilation (PIV, a cutaneous physiological neurovascular mechanism which could delay the occurrence of tissue ischemia), and (2) could be protective against skin pressure ulcer formation. Male Swiss mice aged 5-6 weeks were randomly assigned to four experimental groups. In two groups, diabetes was induced by a single intraperitoneal injection of streptozotocin (STZ, 200 mg.kg(-1)). After 6 weeks, control and STZ mice received either no treatment or candesartan (1 mg/kg-daily in drinking water) during 2 weeks. At the end of treatment (8 weeks of diabetes duration), C-fiber mediated nociception threshold, endothelium-dependent vasodilation and PIV were assessed. Pressure ulcers (PUs) were then induced by pinching the dorsal skin between two magnetic plates for three hours. Skin ulcer area development was assessed during three days, and histological examination of the depth of the skin lesion was performed at day three. After 8 weeks of diabetes, the skin neurovascular functions (C-fiber nociception, endothelium-dependent vasodilation and PIV) were markedly altered in STZ-treated mice, but were fully restored by treatment with candesartan. Whereas in diabetes mice exposure of the skin to pressure induced wide and deep necrotic lesions, treatment with candersartan restored their ability to resist to pressure-induced ulceration as efficiently as the control mice. Candesartan decreases the vulnerability to pressure-induced ulceration and restores skin neurovascular functions in mice with STZ-induced established diabetes.

Differential effect of amylin on endothelial-dependent vasodilation in mesenteric arteries from control and insulin resistant rats.

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Mariam El Assar

Full Text Available Insulin resistance (IR is frequently associated with endothelial dysfunction and has been proposed to play a major role in cardiovascular disease (CVD. On the other hand, amylin has long been related to IR. However the role of amylin in the vascular dysfunction associated to IR is not well addressed. Therefore, the aim of the study was to assess the effect of acute treatment with amylin on endothelium-dependent vasodilation of isolated mesenteric arteries from control (CR and insulin resistant (IRR rats and to evaluate the possible mechanisms involved. Five week-old male Wistar rats received 20% D-fructose dissolved in drinking water for 8 weeks and were compared with age-matched CR. Plasmatic levels of glucose, insulin and amylin were measured. Mesenteric microvessels were dissected and mounted in wire myographs to evaluate endothelium-dependent vasodilation to acetylcholine. IRR displayed a significant increase in plasmatic levels of glucose, insulin and amylin and reduced endothelium-dependent relaxation when compared to CR. Acute treatment of mesenteric arteries with r-amylin (40 pM deteriorated endothelium-dependent responses in CR. Amylin-induced reduction of endothelial responses was unaffected by the H2O2 scavenger, catalase, but was prevented by the extracellular superoxide scavenger, superoxide dismutase (SOD or the NADPH oxidase inhibitor (VAS2870. By opposite, amylin failed to further inhibit the impaired relaxation in mesenteric arteries of IRR. SOD, or VAS2870, but not catalase, ameliorated the impairment of endothelium-dependent relaxation in IRR. At concentrations present in insulin resistance conditions, amylin impairs endothelium-dependent vasodilation in mircrovessels from rats with preserved vascular function and low levels of endogenous amylin. In IRR with established endothelial dysfunction and elevated levels of amylin, additional exposure to this peptide has no effect on endothelial vasodilation. Increased superoxide

Levels and associations among self-esteem, fertility distress, coping, and reaction to potentially being a genetic carrier in women with diminished ovarian reserve.

Science.gov (United States)

Cizmeli, Ceylan; Lobel, Marci; Franasiak, Jason; Pastore, Lisa M

2013-06-01

To measure the level of distress and its relationship with other psychologic factors in women with diminished ovarian reserve (DOR) who participated in a fragile X genetics study. Longitudinal data analyzed with structural equation modeling. Four U.S. private and academic fertility centers. Sixty-two infertile patients with DOR. None. Fertility Problem Inventory, Coping Scale for Infertile Couples, Rosenberg Self-Esteem, Health Orientation Scale. Nineteen percent had low fertility distress, 56% had average fertility distress, and 24% had high fertility distress. Thirty-six percent self-reported a "favorable" or "very favorable" emotional response to potentially being a fragile X carrier (termed "emotions"), 53% were "ambivalent," and 11% had an unfavorable reaction. Three months after learning that they were not a carrier, these percentages were 91%, 9%, and 0%, respectively. Emotions at this second time point were significantly more positive than at pretesting. At baseline, higher self-esteem was a significant predictor of reduced fertility distress both directly and indirectly through emotions. Fertility distress was not associated with coping. Self-esteem, fertility distress, pretesting emotions, and coping were unrelated to posttesting emotions. The potential of having an explanation for one's DOR condition may have a beneficial impact on women's psychologic states during the process of genetic testing, and this appeared to be especially true for women with higher self-esteem. Psychologic interventions targeted to women with low self-esteem may reduce distress and improve reactions to genetic testing. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Elevated blood pressure in cytochrome P4501A1 knockout mice is associated with reduced vasodilation to omega − 3 polyunsaturated fatty acids

Energy Technology Data Exchange (ETDEWEB)

Agbor, Larry N.; Walsh, Mary T.; Boberg, Jason R.; Walker, Mary K., E-mail: mwalker@salud.unm.edu

2012-11-01

In vitro cytochrome P4501A1 (CYP1A1) metabolizes omega − 3 polyunsaturated fatty acids (n − 3 PUFAs); eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), primarily to 17,18-epoxyeicosatetraenoic acid (17,18-EEQ) and 19,20-epoxydocosapentaenoic acid (19,20-EDP), respectively. These metabolites have been shown to mediate vasodilation via increases in nitric oxide (NO) and activation of potassium channels. We hypothesized that genetic deletion of CYP1A1 would reduce vasodilatory responses to n − 3 PUFAs, but not the metabolites, and increase blood pressure (BP) due to decreases in NO. We assessed BP by radiotelemetry in CYP1A1 wildtype (WT) and knockout (KO) mice ± NO synthase (NOS) inhibitor. We also assessed vasodilation to acetylcholine (ACh), EPA, DHA, 17,18-EEQ and 19,20-EDP in aorta and mesenteric arterioles. Further, we assessed vasodilation to an NO donor and to DHA ± inhibitors of potassium channels. CYP1A1 KO mice were hypertensive, compared to WT, (mean BP in mm Hg, WT 103 ± 1, KO 116 ± 1, n = 5/genotype, p < 0.05), and exhibited a reduced heart rate (beats per minute, WT 575 ± 5; KO 530 ± 7; p < 0.05). However, BP responses to NOS inhibition and vasorelaxation responses to ACh and an NO donor were normal in CYP1A1 KO mice, suggesting that NO bioavailability was not reduced. In contrast, CYP1A1 KO mice exhibited significantly attenuated vasorelaxation responses to EPA and DHA in both the aorta and mesenteric arterioles, but normal vasorelaxation responses to the CYP1A1 metabolites, 17,18-EEQ and 19,20-EDP, and normal responses to potassium channel inhibition. Taken together these data suggest that CYP1A1 metabolizes n − 3 PUFAs to vasodilators in vivo and the loss of these vasodilators may lead to increases in BP. -- Highlights: ► CYP1A1 KO mice are hypertensive. ► CYP1A1 KO mice exhibit reduced vasodilation responses to n-3 PUFAs. ► Constitutive CYP1A1 expression regulates blood pressure and vascular function.

Elevated blood pressure in cytochrome P4501A1 knockout mice is associated with reduced vasodilation to omega − 3 polyunsaturated fatty acids

International Nuclear Information System (INIS)

Agbor, Larry N.; Walsh, Mary T.; Boberg, Jason R.; Walker, Mary K.

2012-01-01

In vitro cytochrome P4501A1 (CYP1A1) metabolizes omega − 3 polyunsaturated fatty acids (n − 3 PUFAs); eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), primarily to 17,18-epoxyeicosatetraenoic acid (17,18-EEQ) and 19,20-epoxydocosapentaenoic acid (19,20-EDP), respectively. These metabolites have been shown to mediate vasodilation via increases in nitric oxide (NO) and activation of potassium channels. We hypothesized that genetic deletion of CYP1A1 would reduce vasodilatory responses to n − 3 PUFAs, but not the metabolites, and increase blood pressure (BP) due to decreases in NO. We assessed BP by radiotelemetry in CYP1A1 wildtype (WT) and knockout (KO) mice ± NO synthase (NOS) inhibitor. We also assessed vasodilation to acetylcholine (ACh), EPA, DHA, 17,18-EEQ and 19,20-EDP in aorta and mesenteric arterioles. Further, we assessed vasodilation to an NO donor and to DHA ± inhibitors of potassium channels. CYP1A1 KO mice were hypertensive, compared to WT, (mean BP in mm Hg, WT 103 ± 1, KO 116 ± 1, n = 5/genotype, p < 0.05), and exhibited a reduced heart rate (beats per minute, WT 575 ± 5; KO 530 ± 7; p < 0.05). However, BP responses to NOS inhibition and vasorelaxation responses to ACh and an NO donor were normal in CYP1A1 KO mice, suggesting that NO bioavailability was not reduced. In contrast, CYP1A1 KO mice exhibited significantly attenuated vasorelaxation responses to EPA and DHA in both the aorta and mesenteric arterioles, but normal vasorelaxation responses to the CYP1A1 metabolites, 17,18-EEQ and 19,20-EDP, and normal responses to potassium channel inhibition. Taken together these data suggest that CYP1A1 metabolizes n − 3 PUFAs to vasodilators in vivo and the loss of these vasodilators may lead to increases in BP. -- Highlights: ► CYP1A1 KO mice are hypertensive. ► CYP1A1 KO mice exhibit reduced vasodilation responses to n-3 PUFAs. ► Constitutive CYP1A1 expression regulates blood pressure and vascular function.

Hormonal therapy with estradiol and drospirenone improves endothelium-dependent vasodilation in the coronary bed of ovariectomized spontaneously hypertensive rats

International Nuclear Information System (INIS)

Borgo, M.V.; Claudio, E.R.G.; Silva, F.B.; Romero, W.G.; Gouvea, S.A.; Moysés, M.R.; Santos, R.L.; Almeida, S.A.; Podratz, P.L.; Graceli, J.B.; Abreu, G.R.

2015-01-01

Drospirenone (DRSP) is a progestin with anti-aldosterone properties and it reduces blood pressure in hypertensive women. However, the effects of DRSP on endothelium-dependent coronary vasodilation have not been evaluated. This study investigated the effects of combined therapy with estrogen (E2) and DRSP on endothelium-dependent vasodilation of the coronary bed of ovariectomized (OVX) spontaneously hypertensive rats. Female spontaneously hypertensive rats (n=87) at 12 weeks of age were randomly divided into sham operated (Sham), OVX, OVX treated with E2 (E2), and OVX treated with E2 and DRSP (E2+DRSP) groups. Hemodynamic parameters were directly evaluated by catheter insertion into the femoral artery. Endothelium-dependent vasodilation in response to bradykinin in the coronary arterial bed was assessed using isolated hearts according to a modified Langendorff method. Coronary protein expression of endothelial nitric oxide synthase and estrogen receptor alpha (ER-α) was assessed by Western blotting. Histological slices of coronary arteries were stained with hematoxylin and eosin, and morphometric parameters were analyzed. Oxidative stress was assessed in situ by dihydroethidium fluorescence. Ovariectomy increased systolic blood pressure, which was only prevented by E2+DRSP treatment. Estrogen deficiency caused endothelial dysfunction, which was prevented by both treatments. However, the vasodilator response in the E2+DRSP group was significantly higher at the three highest concentrations compared with the OVX group. Reduced ER-α expression in OVX rats was restored by both treatments. Morphometric parameters and oxidative stress were augmented by OVX and reduced by E2 and E2+DRSP treatments. Hormonal therapy with E2 and DRSP may be an important therapeutic option in the prevention of coronary heart disease in hypertensive post-menopausal women

Hormonal therapy with estradiol and drospirenone improves endothelium-dependent vasodilation in the coronary bed of ovariectomized spontaneously hypertensive rats

Directory of Open Access Journals (Sweden)

M.V. Borgo

2016-01-01

Full Text Available Drospirenone (DRSP is a progestin with anti-aldosterone properties and it reduces blood pressure in hypertensive women. However, the effects of DRSP on endothelium-dependent coronary vasodilation have not been evaluated. This study investigated the effects of combined therapy with estrogen (E2 and DRSP on endothelium-dependent vasodilation of the coronary bed of ovariectomized (OVX spontaneously hypertensive rats. Female spontaneously hypertensive rats (n=87 at 12 weeks of age were randomly divided into sham operated (Sham, OVX, OVX treated with E2 (E2, and OVX treated with E2 and DRSP (E2+DRSP groups. Hemodynamic parameters were directly evaluated by catheter insertion into the femoral artery. Endothelium-dependent vasodilation in response to bradykinin in the coronary arterial bed was assessed using isolated hearts according to a modified Langendorff method. Coronary protein expression of endothelial nitric oxide synthase and estrogen receptor alpha (ER-α was assessed by Western blotting. Histological slices of coronary arteries were stained with hematoxylin and eosin, and morphometric parameters were analyzed. Oxidative stress was assessed in situ by dihydroethidium fluorescence. Ovariectomy increased systolic blood pressure, which was only prevented by E2+DRSP treatment. Estrogen deficiency caused endothelial dysfunction, which was prevented by both treatments. However, the vasodilator response in the E2+DRSP group was significantly higher at the three highest concentrations compared with the OVX group. Reduced ER-α expression in OVX rats was restored by both treatments. Morphometric parameters and oxidative stress were augmented by OVX and reduced by E2 and E2+DRSP treatments. Hormonal therapy with E2 and DRSP may be an important therapeutic option in the prevention of coronary heart disease in hypertensive post-menopausal women.

Hormonal therapy with estradiol and drospirenone improves endothelium-dependent vasodilation in the coronary bed of ovariectomized spontaneously hypertensive rats

Energy Technology Data Exchange (ETDEWEB)

Borgo, M.V.; Claudio, E.R.G.; Silva, F.B.; Romero, W.G.; Gouvea, S.A.; Moysés, M.R.; Santos, R.L.; Almeida, S.A. [Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal de Espírito Santo, Vitória, ES (Brazil); Podratz, P.L.; Graceli, J.B. [Departamento de Morfologia, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Abreu, G.R. [Departamento de Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal de Espírito Santo, Vitória, ES (Brazil)

2015-11-17

Drospirenone (DRSP) is a progestin with anti-aldosterone properties and it reduces blood pressure in hypertensive women. However, the effects of DRSP on endothelium-dependent coronary vasodilation have not been evaluated. This study investigated the effects of combined therapy with estrogen (E2) and DRSP on endothelium-dependent vasodilation of the coronary bed of ovariectomized (OVX) spontaneously hypertensive rats. Female spontaneously hypertensive rats (n=87) at 12 weeks of age were randomly divided into sham operated (Sham), OVX, OVX treated with E2 (E2), and OVX treated with E2 and DRSP (E2+DRSP) groups. Hemodynamic parameters were directly evaluated by catheter insertion into the femoral artery. Endothelium-dependent vasodilation in response to bradykinin in the coronary arterial bed was assessed using isolated hearts according to a modified Langendorff method. Coronary protein expression of endothelial nitric oxide synthase and estrogen receptor alpha (ER-α) was assessed by Western blotting. Histological slices of coronary arteries were stained with hematoxylin and eosin, and morphometric parameters were analyzed. Oxidative stress was assessed in situ by dihydroethidium fluorescence. Ovariectomy increased systolic blood pressure, which was only prevented by E2+DRSP treatment. Estrogen deficiency caused endothelial dysfunction, which was prevented by both treatments. However, the vasodilator response in the E2+DRSP group was significantly higher at the three highest concentrations compared with the OVX group. Reduced ER-α expression in OVX rats was restored by both treatments. Morphometric parameters and oxidative stress were augmented by OVX and reduced by E2 and E2+DRSP treatments. Hormonal therapy with E2 and DRSP may be an important therapeutic option in the prevention of coronary heart disease in hypertensive post-menopausal women.

Does PGE1 Vasodilator Prevent Orthopaedic Implant-Related Infection in Diabetes? Preliminary Results in a Mouse Model

Science.gov (United States)

Lovati, Arianna B.; Romanò, Carlo L.; Monti, Lorenzo; Vassena, Christian; Previdi, Sara; Drago, Lorenzo

2014-01-01

Background Implant-related infections are characterized by bacterial colonization and biofilm formation on the prosthesis. Diabetes represents one of the risk factors that increase the chances of prosthetic infections because of related severe peripheral vascular disease. Vasodilatation can be a therapeutic option to overcome diabetic vascular damages and increase the local blood supply. In this study, the effect of a PGE1 vasodilator on the incidence of surgical infections in diabetic mice was investigated. Methodology A S. aureus implant-related infection was induced in femurs of diabetic mice, then differently treated with a third generation cephalosporin alone or associated with a PGE1 vasodilator. Variations in mouse body weight were evaluated as index of animal welfare. The femurs were harvested after 28 days and underwent both qualitative and quantitative analysis as micro-CT, histological and microbiological analyses. Results The analysis performed in this study demonstrated the increased host response to implant-related infection in diabetic mice treated with the combination of a PGE1 and antibiotic. In this group, restrained signs of infections were identified by micro-CT and histological analysis. On the other hand, the diabetic mice treated with the antibiotic alone showed a severe infection and inability to successfully respond to the standard antimicrobial treatment. Conclusions The present study revealed interesting preliminary results in the use of a drug combination of antibiotic and vasodilator to prevent implant-related Staphylococcus aureus infections in a diabetic mouse model. PMID:24718359

Nitrite-dependent vasodilation is facilitated by hypoxia and is independent of known NO-generating nitrite reductase activities

DEFF Research Database (Denmark)

Fago, Angela; Dalsgaard, Thomas; Fago, Angela

2007-01-01

is largely intrinsic to the vessel and that under hypoxia physiological nitrite concentrations are sufficient to induce NO-mediated vasodilation independently of the nitrite reductase activities investigated here. Possible reaction mechanisms for nitrite vasoactivity, including formation of S...

Role of nitric oxide in vasodilation in upstream muscle during intermittent pneumatic compression.

Science.gov (United States)

Chen, Long-En; Liu, Kang; Qi, Wen-Ning; Joneschild, Elizabeth; Tan, Xiangling; Seaber, Anthony V; Stamler, Jonathan S; Urbaniak, James R

2002-02-01

This study investigated the dosage effects of nitric oxide synthase (NOS) inhibitor N(G)-monomethyl-L-arginine (L-NMMA) on intermittent pneumatic compression (IPC)-induced vasodilation in uncompressed upstream muscle and the effects of IPC on endothelial NOS (eNOS) expression in upstream muscle. After L-NMMA infusion, mean arterial pressure increased by 5% from baseline (99.5 +/- 18.7 mmHg; P < 0.05). Heart rate and respiratory rate were not significantly affected. One-hour IPC application on legs induced a 10% dilation from baseline in 10- to 20-microm arterioles and a 10-20% dilation in 21- to 40 microm arterioles and 41- to 70-microm arteries in uncompressed cremaster muscle. IPC-induced vasodilation was dose dependently reduced, abolished, or even reversed by concurrently infused L-NMMA. Moreover, expression of eNOS mRNA in uncompressed cremaster muscle was upregulated to 2 and 2.5 times normal at the end of 1- and 5-h IPC on legs, respectively, and the expression of eNOS protein was upregulated to 1.8 times normal. These increases returned to baseline level after cessation of IPC. The results suggest that eNOS plays an important role in regulating the microcirculation in upstream muscle during IPC.

Brain SPECT using dipyridamole for evaluation of vascular reserve

International Nuclear Information System (INIS)

Kim, Su Zy; Park, Chan Hee; Yoon, Soo Hwan; Pai, Moon Sun; Yoon, Suk Nam; Cho, Kyung Kee

1997-01-01

Baseline and stress brain SPECT studies using CO 2 inhalation, acetazolamide (Diamox R ) and adenosine administrations have been used in the evaluation of cerebral vascular reserve. Recently dipyridamole (Persantine R ) which is one of the pharmacologic myocardial perfusion SPECT agents as a potent vasodilator is suggested as another cerebral vasodilator. IV Diamox R is not available in Korea. Therefore, the purpose of our study was to evaluate dipyridamole in stress brain SPECT in patients with Moya Moya disease. Eight patients with angiographically proven Moya Moya disease were studied. Their ages ranged from 7 to 62 year old. There were 4 males and 4 females. Each patient had a baseline and persantine brain SPECT studies with 1 to 3 days' interval. Dipyridamole was given intravenously at a dose of 0.56 mg/kg over 4 minutes while watching vital signs such as blood pressure, heart rate, and electrocardiogram. Three minutes after the completion of the infusion, 99mTc-ECD (0.2 mCi/Ib body weight) was injected. Brain SPECT was performed 30 minutes later using a tripple head gamma camera equipped with LEHR collimators. A total of 128 projections with an acquisition time of 30 second per projection was obtained and reconstructed by filtered back projections without attenuation correction. The difference between the baseline and persantine studies was analysed by visual and semiquantitavely. During the infusion of persantine, heart rate, blood pressure and side effects such as headache, chest discomfort were similar to the persantine myocardial SPECT studies. Five of eight patients showed a significant decrease in rCBF on persantine brain SPECT in comparison to the baseline study. The remaining three revealed no significant change in rCBF. Our study suggests that the dipyridamole stress brain SPECT is feasible and useful in assessing cerebral blood flow reserve. However we need to evaluate more number of patients in the future

Antioxidant and Vasodilator Activity of Ugni molinae Turcz. (Murtilla and Its Modulatory Mechanism in Hypotensive Response

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Ignacio Jofré

2016-01-01

Full Text Available Hypertension is a systemic condition with high morbidity and mortality rates worldwide, which poses an increased risk for cardiovascular diseases. In this study, we demonstrated the antioxidant and vasodilator activity of Ugni molinae Turcz. (Murtilla fruit, a berry native to Chile and proposed models to explain its modulatory mechanism in hypotensive response. Murtilla fruits were cultivated in a germplasm bank and submitted to chemical and biological analyses. The phenolic compounds gallic acid, Catechin, Quercetin-3-β-D-glucoside, Myricetin, Quercetin, and Kaempferol were identified. Murtilla extract did not generate toxic effects on human endothelial cells and had significant antioxidant activity against ROS production, lipid peroxidation, and superoxide anion production. Furthermore, it showed dose-dependent vasodilator activity in aortic rings in the presence of endothelium, whose hypotensive mechanism is partially mediated by nitric oxide synthase/guanylate cyclase and large-conductance calcium-dependent potassium channels. Murtilla fruits might potentially have beneficial effects on the management of cardiovascular diseases.

Distribution of the FMR1 gene in females by race/ethnicity: women with diminished ovarian reserve versus women with normal fertility (SWAN study).

Science.gov (United States)

Pastore, Lisa M; Young, Steven L; Manichaikul, Ani; Baker, Valerie L; Wang, Xin Q; Finkelstein, Joel S

2017-01-01

To study whether reported, but inconsistent, associations between the FMR1 CGG repeat lengths in the intermediate, high normal, or low normal range differentiate women diagnosed with diminished ovarian reserve (DOR) from population controls and whether associations vary by race/ethnic group. Case-control study. Academic and private fertility clinics. DOR cases (n = 129; 95 Whites, 22 Asian, 12 other) from five U.S. fertility clinics were clinically diagnosed, with regular menses and no fragile X syndrome family history. Normal fertility controls (n = 803; 386 Whites, 219 African-Americans, 102 Japanese, 96 Chinese) from the United States-based SWAN Study had one or more menstrual period in the 3 months pre-enrollment, one or more pregnancy, no history of infertility or hormone therapy, and menopause ≥46 years. Previously, the SWAN Chinese and Japanese groups had similar FMR1 CGG repeat lengths, thus they were combined. None. FMR1 CGG repeat lengths. Median CGG repeats were nearly identical by case/control group. DOR cases had fewer CGG repeats in the shorter FMR1 allele than controls among Whites, but this was not significant among Asians. White cases had fewer CGG repeats in the shorter allele than Asian cases. No significant differences were found in the high normal/intermediate range between cases and controls or by race/ethnic group within cases in the longer allele. This study refutes prior reports of an association between DOR and high normal/intermediate repeats and confirms an association between DOR and low normal repeats in Whites. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Trans monounsaturated fatty acids and saturated fatty acids have similar effects on postprandial flow-mediated vasodilation

NARCIS (Netherlands)

Roos, de N.M.; Siebelink, E.; Bots, M.L.; Tol, van A.; Schouten, E.G.; Katan, M.B.

2002-01-01

Objective: Several studies suggest that a fatty meal impairs flow-mediated vasodilation (FMD), a measur9e of endothelial function. We tested whether the impairment was greater for trans fats than for saturated fats. We did this because we previously showed that replacement of saturated fats by trans

Nitrite-Mediated Hypoxic Vasodilation Predicted from Mathematical Modeling and Quantified from in Vivo Studies in Rat Mesentery

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Donald G. Buerk

2017-12-01

Full Text Available Nitric oxide (NO generated from nitrite through nitrite reductase activity in red blood cells has been proposed to play a major role in hypoxic vasodilation. However, we have previously predicted from mathematical modeling that much more NO can be derived from tissue nitrite reductase activity than from red blood cell nitrite reductase activity. Evidence in the literature suggests that tissue nitrite reductase activity is associated with xanthine oxidoreductase (XOR and/or aldehyde oxidoreductase (AOR. We investigated the role of XOR and AOR in nitrite-mediated vasodilation from computer simulations and from in vivo exteriorized rat mesentery experiments. Vasodilation responses to nitrite in the superfusion medium bathing the mesentery equilibrated with 5% O2 (normoxia or zero O2 (hypoxia at either normal or acidic pH were quantified. Experiments were also conducted following intraperitoneal (IP injection of nitrite before and after inhibiting XOR with allopurinol or inhibiting AOR with raloxifene. Computer simulations for NO and O2 transport using reaction parameters reported in the literature were also conducted to predict nitrite-dependent NO production from XOR and AOR activity as a function of nitrite concentration, PO2 and pH. Experimentally, the largest arteriolar responses were found with nitrite >10 mM in the superfusate, but no statistically significant differences were found with hypoxic and acidic conditions in the superfusate. Nitrite-mediated vasodilation with IP nitrite injections was reduced or abolished after inhibiting XOR with allopurinol (p < 0.001. Responses to IP nitrite before and after inhibiting AOR with raloxifene were not as consistent. Our mathematical model predicts that under certain conditions, XOR and AOR nitrite reductase activity in tissue can significantly elevate smooth muscle cell NO and can serve as a compensatory pathway when endothelial NO production is limited by hypoxic conditions. Our theoretical and

Diving response in rats: role of the subthalamic vasodilator area.

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Eugene Golanov

2016-09-01

Full Text Available Diving response is a powerful integrative response targeted toward survival of the hypoxic/anoxic conditions. Being present in all animals and humans it allows to survive adverse conditions like diving. Earlier we discovered that forehead stimulation affords neuroprotective effect decreasing infarction volume triggered by permanent occlusion of the middle cerebral artery in rats. We hypothesized that cold stimulation of the forehead induces diving response in rats, which, in turn, exerts neuroprotection. We compared autonomic (AP, HR, CBF and EEG responses to the known diving response-triggering stimulus, ammonia stimulation of the nasal mucosa, cold stimulation of the forehead, and cold stimulation of the glabrous skin of the tail base in anesthetized rats. Responses in AP, HR, CBF and EEG to cold stimulation of the forehead and ammonia vapors instillation into the nasal cavity were comparable and differed significantly from responses to the cold stimulation of the tail base. Excitotoxic lesion of the subthalamic vasodilator area, which is known to participate in CBF regulation and to afford neuroprotection upon excitation, failed to affect autonomic components of the diving response evoked by forehead cold stimulation or nasal mucosa ammonia stimulation. We conclude that cold stimulation of the forehead triggers physiological response comparable to the response evoked by ammonia vapor instillation into the nasal cavity, which considered as stimulus triggering protective diving response. These observations may explain the neuroprotective effect of the forehead stimulation. Data demonstrate that subthalamic vasodilator area does not directly participate in the autonomic adjustments accompanying diving response, however, it is involved in diving-evoked modulation of EEG. We suggest that forehead stimulation can be employed as a stimulus capable of triggering oxygen-conserving diving response and can be used for neuroprotective therapy.

Diagnosis and Treatment of Diminished Ovarian Reserve in ART Cycles of Women Up to Age 40 Years: The Role of Insurance Mandates

Science.gov (United States)

Butts, Samantha F.; Ratcliffe, Sarah; Dokras, Anuja; Seifer, David B.

2012-01-01

Summary Objective To explore correlates of diminished ovarian reserve (DOR) and predictors of ART treatment outcome in DOR cycles using the SART-CORS database. We hypothesized that state insurance coverage for ART is associated with the prevalence of DOR diagnosis in ART cycles and with treatment outcomes in DOR cycles. Design Cross sectional study using ART cycles between 2004–2007. Setting United States ART registry data. Patients 182,779 fresh, non-donor, initial ART cycles in women up to age 40. Interventions None. Main Outcome Measures Prevalence of DOR and elevated FSH, odds ratio of DOR and elevated FSH in ART mandated vs. non-mandated states, live birth rates. Results Compared to cycles performed in states with mandated ART coverage, cycles in states with no ART mandate were more likely to have DOR (AOR 1.43 95% CI 1.37–1.5, pcycles. Conclusions A significant association was observed between lack of mandated insurance for ART and the proportion of cycles treating DOR or elevated FSH. The presence or absence of state mandated ART coverage could impact access to care and the mix of patients that pursue and initiate ART cycles. Additional studies are needed that consider the coalescence of insurance mandates, patient and provider factors, and state level variables on the odds of specific infertility diagnoses and treatment prognosis. PMID:23102859

Induced vasodilation as treatment for Raynaud's disease.

Science.gov (United States)

Jobe, J B; Sampson, J B; Roberts, D E; Beetham, W P

1982-11-01

We examined the efficacy of induced vasodilation as a treatment of idiopathic Raynaud's disease. Eight persons with Raynaud's disease and seven normal persons each received 27 simultaneous pairings of hand immersion in warm water (43 degrees C) for 10 minutes with exposure of the whole body to cold (0 degrees C). A second group of seven normal persons and nine persons with Raynaud's disease received no treatments. All subjects had cold test exposures (0 degrees C) at the start and end of the study. Subjects with Raynaud's disease who received treatments showed significant increases in digital temperatures (2.2 degrees C) during the cold test compared with the values of untreated subjects with Raynaud's disease (p less than 0.05); normal subjects who had received treatments showed no difference from those who had not. Digital temperatures of subjects with Raynaud's disease after treatment increased to levels approaching those of normal subjects, although they showed lower digital temperatures during initial exposure to cold (p less than 0.01). This therapy offers a practical alternative to traditional treatments.

Successful use of continuous vasodilator infusion to treat critical vasospasm threatening a distal bypass

OpenAIRE

Gregory A. Magee, MD, MSc; Anastasia Plotkin, MD; Jeniann A. Yi, MD, MS; Kathryn E. Bowser, MD; David P. Kuwayama, MD, MPA

2018-01-01

Vasospasm immediately after lower extremity arterial bypass may represent an uncommon cause of early graft failure. We report a successful case of catheter-directed, intra-arterial continuous vasodilator infusion to salvage a bypass graft threatened by severe, refractory vasospasm after incomplete response to nicardipine, verapamil, and nitroglycerin boluses. A continuous nitroglycerin infusion was administered for 24 hours, by which time the vasospasm resolved. At 12 months postoperatively, ...

Effect of Melatonin on the Outcome of Assisted Reproductive Technique Cycles in Women with Diminished Ovarian Reserve: A Double-Blinded Randomized Clinical Trial

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Bahia Namavar Jahromi

2017-01-01

Full Text Available Diminished ovarian reserve (DOR significantly decreases the success rate of the assisted reproductive technique (ART. In this study, we assessed the effect of melatonin on the ART outcomes in women with DOR. A double-blinded, randomized, clinical trial was performed on 80 women with DOR as a pilot study in Shiraz, between 2014 and 2015. DOR was defined as the presence of 2 of the following 3 criteria: 1 anti-Müllerian hormone ≤1, 2 folliclestimulating hormone ≥10, and 3 bilateral antral follicle count ≤6. The women received 3 mg/d melatonin or a placebo since the fifth day of one cycle prior to gonadotropin stimulation and continued the treatment up to the time of ovum pickup. The ART outcomes were compared between the groups using SPSS software. Finally, there were 32 women in the case and 34 in the placebo groups. The mean age and basal ovarian reserve test were the same between the groups. The serum estradiol level on the triggering day was significantly higher in the case group (P=0.005. The mean number of MII oocytes was higher in the case group, but the difference did not reach statistical significance. Number of the patients who had mature MII oocytes (P=0.014, top-quality embryos with grade 1 (P=0.049, and embryos with grades 1 and 2 (P=0.014 was higher among the women who received melatonin. However, the other ART outcomes were not different between the groups. The serum estradiol level was higher and more women with DOR had good-quality oocytes and embryos after receiving melatonin; however, no other outcome was different between the case and control groups. Trial Registration Number: IRCT2014041417264N1

The Deletion of Endothelial Sodium Channel α (αENaC Impairs Endothelium-Dependent Vasodilation and Endothelial Barrier Integrity in Endotoxemia in Vivo

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Magdalena Sternak

2018-04-01

Full Text Available The role of epithelial sodium channel (ENaC activity in the regulation of endothelial function is not clear. Here, we analyze the role of ENaC in the regulation of endothelium-dependent vasodilation and endothelial permeability in vivo in mice with conditional αENaC subunit gene inactivation in the endothelium (endo-αENaCKO mice using unique MRI-based analysis of acetylcholine-, flow-mediated dilation and vascular permeability. Mice were challenged or not with lipopolysaccharide (LPS, from Salmonella typhosa, 10 mg/kg, i.p.. In addition, changes in vascular permeability in ex vivo organs were analyzed by Evans Blue assay, while changes in vascular permeability in perfused mesenteric artery were determined by a FITC-dextran-based assay. In basal conditions, Ach-induced response was completely lost, flow-induced vasodilation was inhibited approximately by half but endothelial permeability was not changed in endo-αENaCKO vs. control mice. In LPS-treated mice, both Ach- and flow-induced vasodilation was more severely impaired in endo-αENaCKO vs. control mice. There was also a dramatic increase in permeability in lungs, brain and isolated vessels as evidenced by in vivo and ex vivo analysis in endotoxemic endo-αENaCKO vs. control mice. The impaired endothelial function in endotoxemia in endo-αENaCKO was associated with a decrease of lectin and CD31 endothelial staining in the lung as compared with control mice. In conclusion, the activity of endothelial ENaC in vivo contributes to endothelial-dependent vasodilation in the physiological conditions and the preservation of endothelial barrier integrity in endotoxemia.

Fractional flow reserve in acute coronary syndromes: A review

Directory of Open Access Journals (Sweden)

Nikunj R. Shah

2014-12-01

Full Text Available Fractional flow reserve (FFR assessment provides anatomical and physiological information that is often used to tailor treatment strategies in coronary artery disease. Whilst robust data validates FFR use in stable ischaemic heart disease, its use in acute coronary syndromes (ACS is less well investigated. We critically review the current data surrounding FFR use across the spectrum of ACS including culprit and non-culprit artery analysis. With adenosine being conventionally used to induce maximal hyperaemia during FFR assessment, co-existent clinical conditions may preclude its use during acute myocardial infarction. Therefore, we include a current review of instantaneous wave free ratio as a novel vasodilator independent method of assessing lesion severity as an alternative strategy to guide revascularisation in ACS.

Controlled exposure to particulate matter from urban street air is associated with decreased vasodilation and heart rate variability in overweight and older adults

DEFF Research Database (Denmark)

Hemmingsen, Jette Gjerke; Rissler, Jenny; Lykkesfeldt, Jens

2015-01-01

, age 55 to 83 years, body mass index > 25 kg/m(2)) were included in a cross-over study with 5 hours of exposure to particle- or sham-filtered air from a busy street using an exposure-chamber. The sham- versus particle-filtered air had average particle number concentrations of ~23.000 versus ~1800/cm(3...... counts). RESULTS: Nitroglycerin-induced vasodilation was reduced by 12% [95% confidence interval: -22%; -1.0%] following PM exposure, whereas hyperemia-induced vasodilation was reduced by 5% [95% confidence interval: -11.6%; 1.6%]. Moreover, HRV measurements showed that the high and low frequency domains...

Skeletal muscle beta-receptors and isoproterenol-stimulated vasodilation in canine heart failure

International Nuclear Information System (INIS)

Frey, M.J.; Lanoce, V.; Molinoff, P.B.; Wilson, J.R.

1989-01-01

To investigate whether heart failure alters beta-adrenergic receptors on skeletal muscle and its associated vasculature, the density of beta-adrenergic receptors, isoproterenol-stimulated adenylate cyclase activity, and coupling of the guanine nucleotide-binding regulatory protein were compared in 18 control dogs and 16 dogs with heart failure induced by 5-8 wk of ventricular pacing at 260 beats/min. Hindlimb vascular responses to isoproterenol were compared in eight controls and eight of the dogs with heart failure. In dogs with heart failure, the density of beta-receptors on skeletal muscle was reduced in both gastrocnemius (control: 50 +/- 5; heart failure: 33 +/- 8 fmol/mg of protein) and semitendinosus muscle (control: 43 +/- 9; heart failure: 27 +/- 9 fmol/mg of protein, both P less than 0.05). Receptor coupling to the ternary complex, as determined by isoproterenol competition curves with and without guanosine 5'-triphosphate (GTP), was unchanged. Isoproterenol-stimulated adenylate cyclase activity was significantly decreased in semitendinosus muscle (control: 52.4 +/- 4.6; heart failure: 36.5 +/- 9.5 pmol.mg-1.min-1; P less than 0.05) and tended to be decreased in gastrocnemius muscle (control: 40.1 +/- 8.5; heart failure: 33.5 +/- 4.5 pmol.mg-1.min-1; P = NS). Isoproterenol-induced hindlimb vasodilation was not significantly different in controls and in dogs with heart failure. These findings suggest that heart failure causes downregulation of skeletal muscle beta-adrenergic receptors, probably due to receptor exposure to elevated catecholamine levels, but does not reduce beta-receptor-mediated vasodilation in muscle

Are there Diminishing Returns to R&D?

DEFF Research Database (Denmark)

Madsen, Jakob B.

Semi-endogenous models and, to some extent, also Schumpeterian models are based on the assumption of diminishing returns to R&D. This paper shows that the null hypothesis of constant returns to R&D cannot be rejected for the OECD countries......Semi-endogenous models and, to some extent, also Schumpeterian models are based on the assumption of diminishing returns to R&D. This paper shows that the null hypothesis of constant returns to R&D cannot be rejected for the OECD countries...

Vasodilator Therapy: Nitrates and Nicorandil.

Science.gov (United States)

Tarkin, Jason M; Kaski, Juan Carlos

2016-08-01

Nitrates have been used to treat symptoms of chronic stable angina for over 135 years. These drugs are known to activate nitric oxide (NO)-cyclic guanosine-3',-5'-monophasphate (cGMP) signaling pathways underlying vascular smooth muscle cell relaxation, albeit many questions relating to how nitrates work at the cellular level remain unanswered. Physiologically, the anti-angina effects of nitrates are mostly due to peripheral venous dilatation leading to reduction in preload and therefore left ventricular wall stress, and, to a lesser extent, epicardial coronary artery dilatation and lowering of systemic blood pressure. By counteracting ischemic mechanisms, short-acting nitrates offer rapid relief following an angina attack. Long-acting nitrates, used commonly for angina prophylaxis are recommended second-line, after beta-blockers and calcium channel antagonists. Nicorandil is a balanced vasodilator that acts as both NO donor and arterial K(+) ATP channel opener. Nicorandil might also exhibit cardioprotective properties via mitochondrial ischemic preconditioning. While nitrates and nicorandil are effective pharmacological agents for prevention of angina symptoms, when prescribing these drugs it is important to consider that unwanted and poorly tolerated hemodynamic side-effects such as headache and orthostatic hypotension can often occur owing to systemic vasodilatation. It is also necessary to ensure that a dosing regime is followed that avoids nitrate tolerance, which not only results in loss of drug efficacy, but might also cause endothelial dysfunction and increase long-term cardiovascular risk. Here we provide an update on the pharmacological management of chronic stable angina using nitrates and nicorandil.

Redundant Vasodilator Pathways Underlying Radial Artery Flow-Mediated Dilation Are Preserved in Healthy Aging

Directory of Open Access Journals (Sweden)

Kevin D. Ballard

2014-01-01

Full Text Available Background. Blocking nitric oxide (NO and vasodilator prostanoids (PN does not consistently reduce flow-mediated dilation (FMD in young adults. The impact of aging on the contribution of NO and PG to FMD is unknown. Methods. FMD was measured in older adults (n=10, 65±3 y after arterial infusion of saline, N(G-monomethyl-L-arginine (L-NMMA, and ketorolac + L-NMMA. Data were compared to published data in young adults. Results. L-NMMA reduced FMD in older adults (8.9±3.6 to 5.9±3.7% although this was not statistically significant (P=0.08 and did not differ (P=0.74 from the reduction observed in young adults (10.0±3.8 to 7.6±4.7%; P=0.03. Blocking PN did not affect FMD in young or older adults. In older adults, L-NMMA reduced (n=6; range = 36–123% decrease, augmented (n=3; 10–122% increase, or did not change FMD (n=1; 0.4% increase. After PN blockade, FMD responses were reduced (n=2, augmented (n=6, or unaffected (n=1. Conclusions. NO or PN blockade did not consistently reduce FMD in healthy older adults, suggesting the existence of redundant vasodilator phenotypes as observed previously in young adults.

Contraction-evoked vasodilation and functional hyperaemia are compromised in branching skeletal muscle arterioles of young pre-diabetic mice.

Science.gov (United States)

Novielli, N M; Jackson, D N

2014-06-01

To investigate the effects of pre-diabetes on microvascular network function in contracting skeletal muscle. We hypothesized that pre-diabetes compromises contraction-evoked vasodilation of branching second-order (2A), third-order (3A) and fourth-order (4A) arterioles, where distal arterioles would be affected the greatest. Intravital video microscopy was used to measure arteriolar diameter (in 2A, 3A and 4A) and blood flow (in 2A and 3A) changes to electrical field stimulation of the gluteus maximus muscle in pre-diabetic (The Pound Mouse, PD) and control (c57bl6, CTRL) mice. Baseline diameter and blood flow were similar between groups (2A: ~20 μm, 3A: ~14 μm and 4A: ~8 μm; 2A: ~1 nL s(-1) and 3A: ~0.5 nL s(-1) ). Single tetanic contraction (100 Hz; 200, 400, 800 ms duration) evoked rapid-onset vasodilation (ROV) and blood flow responses that were blunted by ~50% and up to 81%, respectively, in PD vs. CTRL (P contraction (2 and 8 Hz, 30 s) evoked vasodilatory and blood flow responses that were also attenuated by ~50% and up to 71%, respectively, in PD vs. CTRL (P contraction was also up to 2.5-fold greater at 4A vs. 2A in CTRL; however spatial differences in vasodilation across arteriolar branch orders was disrupted in PD. Arteriolar dysregulation in pre-diabetes causes deficits in contraction-evoked dilation and blood flow, where greatest deficits occur at distal arterioles. © 2014 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

Reduced coronary flow and resistance reserve in primary scleroderma myocardial disease

International Nuclear Information System (INIS)

Nitenberg, A.; Foult, J.M.; Kahan, A.; Perennec, J.; Devaux, J.Y.; Menkes, C.J.; Amor, B.

1986-01-01

The maximum coronary vasodilator capacity after intravenous dipyridamole (0.14 mg X kg-1 X min-1 X 4 minutes) was studied in seven patients with primary scleroderma myocardial disease and compared to that of seven control subjects. Hemodynamic data and left ventricular angiographic data were not different in the two groups. The coronary flow reserve was evaluated by the dipyridamole/basal coronary sinus blood flow ratio (D/B CSBF) and the coronary resistance reserve by the dipyridamole/basal coronary resistance ratio (D/B CR). Coronary reserve was greatly impaired in the group with primary scleroderma myocardial disease: D/B CSBF was lower than in the control group (2.54 +/- 1.37 vs 4.01 +/- 0.56, respectively; p less than 0.05) and D/B CR was higher than in the control group (0.47 +/- 0.25 vs 0.23 +/- 0.04, respectively; p less than 0.05). Such a decreased coronary flow and resistance reserve in patients with primary scleroderma myocardial disease was not explained by an alteration of left ventricular function. It may be an important contributing factor in the pathogenesis of primary scleroderma myocardial disease

Augmented H2S production via cystathionine-beta-synthase upregulation plays a role in pregnancy-associated uterine vasodilation.

Science.gov (United States)

Sheibani, Lili; Lechuga, Thomas J; Zhang, Honghai; Hameed, Afshan; Wing, Deborah A; Kumar, Sathish; Rosenfeld, Charles R; Chen, Dong-Bao

2017-03-01

Endogenous hydrogen sulfide (H2S) synthesized via metabolizing L-cysteine by cystathionine-beta-synthase (CBS) and cystathionine-gamma-lyase (CSE) is a potent vasodilator and angiogenic factor. The objectives of this study were to determine if human uterine artery (UA) H2S production increases with augmented expression and/or activity of CBS and/or CSE during the menstrual cycle and pregnancy and whether exogenous H2S dilates UA. Uterine arteries from nonpregnant (NP) premenopausal proliferative (pPRM) and secretory (sPRM) phases of the menstrual cycle and pregnant (P) women were studied. H2S production was measured by the methylene blue assay. CBS and CSE mRNAs were assessed by quantitative real-time PCR, and proteins were assessed by immunoblotting and semiquantitative immunofluorescence microscopy. Effects of H2S on rat UA relaxation were determined by wire myography ex vivo. H2S production was greater in NP pPRM and P than NP sPRM UAs and inhibited by the specific CBS but not CSE inhibitor. CBS but not CSE mRNA and protein were greater in NP pPRM and P than NP sPRM UAs. CBS protein was localized to endothelium and smooth muscle and its levels were in a quantitative order of P >NP UAs of pPRM>sPRM. CSE protein was localized in UA endothelium and smooth muscle with no difference among groups. A H2S donor relaxed P > NP UAs but not mesentery artery. Thus, human UA H2S production is augmented with endothelium and smooth muscle CBS upregulation, contributing to UA vasodilation in the estrogen-dominant physiological states in the proliferative phase of the menstrual cycle and pregnancy. © The Authors 2017. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Effects of endogenous nitric oxide on adrenergic nerve-mediated vasoconstriction and calcitonin gene-related peptide-containing nerve-mediated vasodilation in pithed rats.

Science.gov (United States)

Yamawaki, Kousuke; Zamami, Yoshito; Kawasaki, Hiromu; Takatori, Shingo

2017-05-05

Vascular adrenergic nerves mainly regulate the tone of blood vessels. Calcitonin gene-related peptide-containing (CGRPergic) vasodilator nerves also participate in the regulation of vascular tone. Furthermore, there are nitric oxide (NO)-containing (nitrergic) nerves, which include NO in blood vessels as vasodilator nerves, but it remains unclear whether nitrergic nerves participate in vascular regulation. The present study investigated the role of nitrergic nerves in vascular responses to spinal cord stimulation (SCS) and vasoactive agents in pithed rats. Wistar rats were anesthetized and pithed, and vasopressor responses to SCS and injections of norepinephrine were observed. To evaluate vasorelaxant responses, the BP was increased by a continuous infusion of methoxamine with hexamethonium to block autonomic outflow. After the elevated BP stabilized, SCS and injections of acetylcholine (ACh), sodium nitroprusside (SNP), and CGRP were intravenously administered. We then evaluated the effects of the NO synthase (NOS) inhibitor, N-ω-nitro-L-arginine methylester hydrochloride (L-NAME), on these vascular responses. Pressor responses to SCS and norepinephrine in pithed rats were enhanced by L-NAME, while the combined infusion of L-NAME and L-arginine had no effect on these responses. L-NAME infusion significantly increased the release of norepinephrine evoked by SCS. In pithed rats with artificially increased BP and L-NAME infusion, depressor response to ACh (except for 0.05nmol/kg) was suppressed and SNP (only 2nmol/kg) was enhanced. However, depressor responses to SCS and CGRP were similar to control responses. The present results suggest endogenous NO regulates vascular tone through endothelium function and inhibition of adrenergic neurotransmission, but not through CGRPergic nerves. Copyright © 2017 Elsevier B.V. All rights reserved.

Polar compounds isolated from the leaves of Calea prunifolia H.B.K. and their anti-adrenergic related vasodilator activity

International Nuclear Information System (INIS)

Puebla, Pilar; San Feliciano, Arturo; Aranguren, Nataly; Rincon, Javier; Rojas, Maritza; Guerrero, Mario

2011-01-01

The leaves of Calea prunifolia H.B.K., medicinal specie used in Colombian folk medicine for hypertension have been analysed for their chemical constituents, resulting in the isolation of one flavonoid glycoside, one quinic acid derivative and one kaurane diterpenoid glycoside. Their chemical structures were elucidated on the basis of spectral analysis, including HRMS, 1D- and 2D-NMR data. The vasodilator effect related to anti adrenergic activity of the three compounds was evaluated in isolated aortic rings from Wistar rats contracted cumulatively with phenylephrine (from 1 x 10 -9 to 5 x 10 -5 mol L -1 ). Although these compounds were devoid of significant vasodilator activity when they were tested alone (1 μg mL-1), mixtures of them (1:1:1) and the own EtOH extract exerted preventive anti-adrenergic activity increasing the phenylephrine CE 50 from 2.3 x 10 -8 to 1.3 x 10 -7 and 8.0 x 10 -7 mol L -1 , respectively. (author)

A Rare Case of Intermittent Claudication Associated with Impaired Arterial Vasodilation

Directory of Open Access Journals (Sweden)

J. J. Posthuma

2017-01-01

Full Text Available Exercise-related intermittent claudication is marked by reduced blood flow to extremities caused by either stenosis or impaired vascular function. Although intermittent claudication is common in the elderly, it rarely occurs in the young and middle-aged individuals. Here, we report a case of exercise-related claudication in a 41-year-old woman, in the absence of overt vascular pathology. Using a series of imaging and functional tests, we established that her complaints were due to impaired arterial vasodilation, possibly due to a defect in nitrous oxide-mediated dilation. The symptoms were reversible upon administration of a calcium antagonist, showing reversibility of the vascular impairment. Identification of reversible vascular “stiffness” merits consideration in young and otherwise healthy subjects with claudication of unknown origin.

Adaptive training diminishes distractibility in aging across species.

Science.gov (United States)

Mishra, Jyoti; de Villers-Sidani, Etienne; Merzenich, Michael; Gazzaley, Adam

2014-12-03

Aging is associated with deficits in the ability to ignore distractions, which has not yet been remediated by any neurotherapeutic approach. Here, in parallel auditory experiments with older rats and humans, we evaluated a targeted cognitive training approach that adaptively manipulated distractor challenge. Training resulted in enhanced discrimination abilities in the setting of irrelevant information in both species that was driven by selectively diminished distraction-related errors. Neural responses to distractors in auditory cortex were selectively reduced in both species, mimicking the behavioral effects. Sensory receptive fields in trained rats exhibited improved spectral and spatial selectivity. Frontal theta measures of top-down engagement with distractors were selectively restrained in trained humans. Finally, training gains generalized to group and individual level benefits in aspects of working memory and sustained attention. Thus, we demonstrate converging cross-species evidence for training-induced selective plasticity of distractor processing at multiple neural scales, benefitting distractor suppression and cognitive control. Copyright © 2014 Elsevier Inc. All rights reserved.

Fluid replacement modulates oxidative stress- but not nitric oxide-mediated cutaneous vasodilation and sweating during prolonged exercise in the heat.

Science.gov (United States)

McNeely, Brendan D; Meade, Robert D; Fujii, Naoto; Seely, Andrew J E; Sigal, Ronald J; Kenny, Glen P

2017-12-01

The roles of nitric oxide synthase (NOS), reactive oxygen species (ROS), and angiotensin II type 1 receptor (AT 1 R) activation in regulating cutaneous vasodilation and sweating during prolonged (≥60 min) exercise are currently unclear. Moreover, it remains to be determined whether fluid replacement (FR) modulates the above thermoeffector responses. To investigate, 11 young men completed 90 min of continuous moderate intensity (46% V̇o 2peak ) cycling performed at a fixed rate of metabolic heat production of 600 W (No FR condition). On a separate day, participants completed a second session of the same protocol while receiving FR to offset sweat losses (FR condition). Cutaneous vascular conductance (CVC) and local sweat rate (LSR) were measured at four intradermal microdialysis forearm sites perfused with: 1 ) lactated Ringer (Control); 2 ) 10 mM N G -nitro-l-arginine methyl ester (l-NAME, NOS inhibition); 3 ) 10 mM ascorbate (nonselective antioxidant); or 4 ) 4.34 nM losartan (AT 1 R inhibition). Relative to Control (71% CVC max at both time points), CVC with ascorbate (80% and 83% CVC max ) was elevated at 60 and 90 min of exercise during FR (both P 0.31). In both conditions, CVC was reduced at end exercise with l-NAME (60% CVC max ; both P 0.19). LSR did not differ between sites in either condition (all P > 0.10). We conclude that NOS regulates cutaneous vasodilation, but not sweating, irrespective of FR, and that ROS influence cutaneous vasodilation during prolonged exercise with FR. Copyright © 2017 the American Physiological Society.

Melatonin mediates vasodilation through both direct and indirect activation of BKCa channels.

Science.gov (United States)

Zhao, T; Zhang, H; Jin, C; Qiu, F; Wu, Y; Shi, L

2017-10-01

Melatonin, synthesized primarily by the pineal gland, is a neuroendocrine hormone with high membrane permeability. The vascular effects of melatonin, including vasoconstriction and vasodilation, have been demonstrated in numerous studies. However, the mechanisms underlying these effects are not fully understood. Large-conductance Ca 2+ -activated K + (BK Ca ) channels are expressed broadly on smooth muscle cells and play an important role in vascular tone regulation. This study explored the mechanisms of myocyte BK Ca channels and endothelial factors underlying the action of melatonin on the mesenteric arteries (MAs). Vascular contractility and patch-clamp studies were performed on myocytes of MAs from Wistar rats. Melatonin induced significant vasodilation on MAs. In the presence of N ω -nitro-l-arginine methyl ester (l-NAME), a potent endothelial oxide synthase (eNOS) inhibitor, melatonin elicited concentration-dependent relaxation, with lowered pIC 50 The effect of melatonin was significantly attenuated in the presence of BK Ca channel blocker iberiotoxin or MT1/MT2 receptor antagonist luzindole in both (+) l-NAME and (-) l-NAME groups. In the (+) l-NAME group, iberiotoxin caused a parallel rightward shift of the melatonin concentration-relaxation curve, with pIC 50 lower than that of luzindole. Both inside-out and cell-attached patch-clamp recordings showed that melatonin significantly increased the open probability, mean open time and voltage sensitivity of BK Ca channels. In a cell-attached patch-clamp configuration, the melatonin-induced enhancement of BK Ca channel activity was significantly suppressed by luzindole. These findings indicate that in addition to the activation of eNOS, melatonin-induced vasorelaxation of MAs is partially attributable to its direct (passing through the cell membrane) and indirect (via MT1/MT2 receptors) activation of the BK Ca channels on mesenteric arterial myocytes. © 2017 Society for Endocrinology.

Affinin (Spilanthol, Isolated from Heliopsis longipes, Induces Vasodilation via Activation of Gasotransmitters and Prostacyclin Signaling Pathways

Directory of Open Access Journals (Sweden)

Jesús Eduardo Castro-Ruiz

2017-01-01

Full Text Available Heliopsis longipes roots have been widely used in Mexican traditional medicine to relieve pain, mainly, toothaches. Previous studies have shown that affinin, the major alkamide of these roots, induces potent antinociceptive and anti-inflammatory activities. However, the effect of H. longipes root extracts and affinin on the cardiovascular system have not been investigated so far. In the present study, we demonstrated that the dichloromethane and ethanolic extracts of H. longipes roots, and affinin, isolated from these roots, produce a concentration-dependent vasodilation of rat aorta. Affinin-induced vasorelaxation was partly dependent on the presence of endothelium and was significantly blocked in the presence of inhibitors of NO, H2S, and CO synthesis (NG-nitro-l-arginine methyl ester (l-NAME, dl-propargylglycine (PAG, and chromium mesoporphyrin (CrMP, respectively; K+ channel blockers (glibenclamide (Gli and tetraethyl ammonium (TEA, and guanylate cyclase and cyclooxygenase inhibitors (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ and indomethacin (INDO, respectively. Our results demonstrate, for the first time, that affinin induces vasodilation by mechanisms that involve gasotransmitters, and prostacyclin signaling pathways. These findings indicate that this natural alkamide has therapeutic potential in the treatment of cardiovascular diseases.

Intra-arterial vasodilators to prevent radial artery spasm: a systematic review and pooled analysis of clinical studies

Energy Technology Data Exchange (ETDEWEB)

Kwok, Chun Shing, E-mail: shingkwok@doctors.org.uk [Keele Cardiovascular Research Group, Keele University, Stoke-on-Trent (United Kingdom); Rashid, Muhammad [St. Helens & Knowsley Teaching Hospital (NHS) Trust, Whiston Hospital, Prescot (United Kingdom); Fraser, Doug [Manchester Heart Centre, Manchester Royal Infirmary (United Kingdom); Nolan, James [University Hospital of North Midlands, Stoke-on-Trent (United Kingdom); Mamas, Mamas [Keele Cardiovascular Research Group, Keele University, Stoke-on-Trent (United Kingdom); Farr Institute, Institute of Population Health, University of Manchester, Manchester (United Kingdom)

2015-12-15

Objectives: The aim of this study is to review the available literature on the efficacy and safety of agents used for prevention of RAS. Background: Different vasodilator agents have been used to prevent radial artery spasm (RAS) in patients undergoing transradial cardiac catheterization. Methods: We included studies that evaluated any intra-arterial drug administered in the setting cardiac catheterization that was undertaken through the transradial access site (TRA). We also compared studies for secondary outcomes of major bleeding, procedure time, and procedure failure rate in setting of RAS prevention, patent hemostasis and radial artery occlusion. Results: 22 clinical studies met the inclusion criteria. For placebo, RAS rate was 12% (4 studies, 638 participants), which was similar to 2.5 mg of verapamil 12% (3 studies, 768 participants) but greater than 5 mg of verapamil (4%, 2 studies, 497 participants). For nicorandil, there was a much higher RAS rate compared to placebo (16%, 3 studies, 447 participants). The lowest rates of RAS was found for nitroglycerin at both 100 μg (4%) and 200 μg (2%) doses, isosorbide mononitrate (4%) and nicardipine (3%). We found no information regarding the procedure failure rates, patent hemostasis, and radial artery occlusion in these studies. Conclusions: In this largest and up-to-date review on intra-arterial vasodilators use to reduce RAS, we have found that the verapamil at a dose of 5 mg or verapamil in combination with nitroglycerine are the best combinations to reduce RAS. - Highlights: • Radial artery spasm (RAS) causes procedural failure in transradial catheterization. • RAS may complicate 10–15% procedures undertaken through the radial approach. • We reviewed the efficacy of vasodilators that have been used to minimize RAS. • The pooled RAS rate was lowest with 5 mg of verapamil (4%) compared to placebo (12%). • The best combination of drugs to minimize RAS is nitroglycerine and verapamil.

Our experience in the treatment of idiopathic sensorineural hearing loss (ISNHL): Effect of combination therapy with HBO2 and vasodilator infusion therapy

Czech Academy of Sciences Publication Activity Database

Kratochvílová, B.; Profant, Oliver; Astl, J.; Holý, R.

2016-01-01

Roč. 43, č. 7 (2016), s. 771-780 ISSN 1066-2936 Institutional support: RVO:68378041 Keywords : idiopathic sensorineural hearing logs * vasodilator infusion * hyperbaric oxygen therapy Subject RIV: FH - Neurology Impact factor: 0.895, year: 2016

Rho-kinase inhibitor and nicotinamide adenine dinucleotide phosphate oxidase inhibitor prevent impairment of endothelium-dependent cerebral vasodilation by acute cigarette smoking in rats.

Science.gov (United States)

Iida, Hiroki; Iida, Mami; Takenaka, Motoyasu; Fukuoka, Naokazu; Dohi, Shuji

2008-06-01

We previously reported that acute cigarette smoking can cause a dysfunction of endothelium-dependent vasodilation in cerebral vessels, and that blocking the angiotensin II (Ang II) type 1 (AT1) receptor with valsartan prevented this impairment. Our aim was to investigate the effects of a Rho-kinase inhibitor (fasudil) and a Nicotinamide Adenine Dinucleotide PHosphate (NADPH) oxidase inhibitor (apocynin) on smoking-induced endothelial dysfunction in cerebral arterioles. In Sprague-Dawley rats, we used a closed cranial window preparation to measure changes in pial vessel diameters following topical acetylcholine (ACh) before smoking. After one-minute smoking, we again examined the arteriolar responses to ACh. Finally, after intravenous fasudil or apocynin pre-treatment we re-examined the vasodilator responses to topical ACh (before and after cigarette smoking). Under control conditions, cerebral arterioles were dose-dependently dilated by topical ACh (10(-6) M and 10(-5) M). One hour after a one-minute smoking (1 mg-nicotine cigarette), 10(-5) M ACh constricted cerebral arterioles. However, one hour after a one-minute smoking, 10(-5) M ACh dilated cerebral pial arteries both in the fasudil pre-treatment and the apocynin pre-treatment groups, responses that were significantly different from those obtained without fasudil or apocynin pre-treatment. Thus, inhibition of Rho-kinase and NADPH oxidase activities may prevent the above smoking-induced impairment of endothelium-dependent vasodilation.

Polar compounds isolated from the leaves of Calea prunifolia H.B.K. and their anti-adrenergic related vasodilator activity

Energy Technology Data Exchange (ETDEWEB)

Puebla, Pilar; San Feliciano, Arturo [Laboratory of Organic and Pharmaceutical Chemistry, Faculty of Pharmacy, Campus Miguel de Unamuno, Salamanca University (Spain); Aranguren, Nataly; Rincon, Javier; Rojas, Maritza; Guerrero, Mario, E-mail: mfguerrerop@unal.edu.co [Pharmacy Department, School of Sciences, National University of Colombia, Bogota D.C. (Colombia)

2011-09-15

The leaves of Calea prunifolia H.B.K., medicinal specie used in Colombian folk medicine for hypertension have been analysed for their chemical constituents, resulting in the isolation of one flavonoid glycoside, one quinic acid derivative and one kaurane diterpenoid glycoside. Their chemical structures were elucidated on the basis of spectral analysis, including HRMS, 1D- and 2D-NMR data. The vasodilator effect related to anti adrenergic activity of the three compounds was evaluated in isolated aortic rings from Wistar rats contracted cumulatively with phenylephrine (from 1 x 10{sup -9} to 5 x 10{sup -5} mol L{sup -1}). Although these compounds were devoid of significant vasodilator activity when they were tested alone (1 {mu}g mL-1), mixtures of them (1:1:1) and the own EtOH extract exerted preventive anti-adrenergic activity increasing the phenylephrine CE{sub 50} from 2.3 x 10{sup -8} to 1.3 x 10{sup -7} and 8.0 x 10{sup -7} mol L{sup -1}, respectively. (author)

Relationship between instantaneous wave-free ratio and fractional flow reserve in patients receiving hemodialysis.

Science.gov (United States)

Morioka, Yuta; Arashi, Hiroyuki; Otsuki, Hisao; Yamaguchi, Junichi; Hagiwara, Nobuhisa

2017-06-22

Instantaneous wave-free ratio (iFR) is a vasodilator-free index and is reported to have a good correlation with fractional flow reserve (FFR). Hemodialysis patients exhibit left ventricular hypertrophy, reduced arterial compliance, and impaired microcirculation. Such a coronary flow condition in these patients may influence the relationship between iFR and FFR. This study assessed the impact of hemodialysis on the relationship between iFR and FFR. The study enrolled 196 patients with 265 stenoses who underwent assessment via iFR, FFR assessment, and right heart catheterization. A good correlation between iFR and FFR was observed in hemodialysis patients. iFR in the hemodialysis group was significantly lower than in the non-hemodialysis group (0.81 ± 0.13 vs. 0.86 ± 0.13, p = 0.005), although no significant difference was found in FFR and percentage diameter stenosis. An iFR value of 0.84 was found to be equivalent to an FFR value of 0.8 in hemodialysis patients, which was lower than the standard predictive iFR range for ischemia. Vasodilator-free assessment by iFR could be beneficial in evaluating intermediate coronary stenosis in patients receiving hemodialysis. However, the threshold for iFR abnormality needs adjustment in hemodialysis patients, and larger clinical trials are required to confirm the results in this specific subset.

Cell-phone use diminishes self-awareness of impaired driving.

Science.gov (United States)

Sanbonmatsu, David M; Strayer, David L; Biondi, Francesco; Behrends, Arwen A; Moore, Shannon M

2016-04-01

Multitasking diminishes the self-awareness of performance that is often essential for self-regulation and self-knowledge. Participants drove in a simulator while either talking or not talking on a hands-free cell phone. Following previous research, participants who talked on a cell phone made more serious driving errors than control participants who did not use a phone while driving. Control participants' assessments of the safeness of their driving and general ability to drive safely while distracted were negatively correlated with the actual number of errors made when they were driving. By contrast, cell-phone participants' assessments of the safeness of their driving and confidence in their driving abilities were uncorrelated with their actual errors. Thus, talking on a cell phone not only diminished the safeness of participants' driving, it diminished their awareness of the safeness of their driving.

A critical role for astrocytes in hypercapnic vasodilation in brain

DEFF Research Database (Denmark)

Howarth, C; Sutherland, B A; Choi, H B

2017-01-01

increases in astrocyte calcium signaling which in turn stimulates COX-1 activity and generates downstream PgE2 production. We demonstrate that astrocyte calcium-evoked production of the vasodilator, PgE2, is critically dependent on brain levels of the antioxidant, glutathione. These data suggest a novel......Cerebral blood flow (CBF) is controlled by arterial blood pressure, arterial CO2, arterial O2, and brain activity and is largely constant in the awake state. Although small changes in arterial CO2 are particularly potent to change CBF (1 mmHg variation in arterial CO2 changes CBF by 3...... in brain slices with in vivo work in rats and C57Bl/6J mice to examine the hemodynamic responses to CO2 and somatosensory stimulation before and after inhibition of astrocytic glutathione and PgE2 synthesis. We demonstrate that hypercapnia (increased CO2) evokes an increase in astrocyte [Ca(2+)]i...

Modulation of vasodilator response via the nitric oxide pathway after acute methyl mercury chloride exposure in rats.

Science.gov (United States)

Omanwar, S; Saidullah, B; Ravi, K; Fahim, M

2013-01-01

Mercury exposure induces endothelial dysfunction leading to loss of endothelium-dependent vasorelaxation due to decreased nitric oxide (NO) bioavailability via increased oxidative stress. Our aim was to investigate whether acute treatment with methyl mercury chloride changes the endothelium-dependent vasodilator response and to explore the possible mechanisms behind the observed effects. Wistar rats were treated with methyl mercury chloride (5 mg/kg, po.). The methyl mercury chloride treatment resulted in an increased aortic vasorelaxant response to acetylcholine (ACh). In methyl-mercury-chloride-exposed rats, the % change in vasorelaxant response of ACh in presence of Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME; 10(-4) M) was significantly increased, and in presence of glybenclamide (10(-5) M), the response was similar to that of untreated rats, indicating the involvement of NO and not of endothelium-derived hyperpolarizing factor (EDHF). In addition, superoxide dismutase (SOD) + catalase treatment increased the NO modulation of vasodilator response in methyl-mercury-chloride-exposed rats. Our results demonstrate an increase in the vascular reactivity to ACh in aorta of rats acutely exposed to methyl mercury chloride. Methyl mercury chloride induces nitric oxide synthase (NOS) and increases the NO production along with inducing oxidative stress without affecting the EDHF pathway.

Modulation of Vasodilator Response via the Nitric Oxide Pathway after Acute Methyl Mercury Chloride Exposure in Rats

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S. Omanwar

2013-01-01

Full Text Available Mercury exposure induces endothelial dysfunction leading to loss of endothelium-dependent vasorelaxation due to decreased nitric oxide (NO bioavailability via increased oxidative stress. Our aim was to investigate whether acute treatment with methyl mercury chloride changes the endothelium-dependent vasodilator response and to explore the possible mechanisms behind the observed effects. Wistar rats were treated with methyl mercury chloride (5 mg/kg, po.. The methyl mercury chloride treatment resulted in an increased aortic vasorelaxant response to acetylcholine (ACh. In methyl-mercury-chloride-exposed rats, the % change in vasorelaxant response of ACh in presence of Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME; 10-4 M was significantly increased, and in presence of glybenclamide (10-5 M, the response was similar to that of untreated rats, indicating the involvement of NO and not of endothelium-derived hyperpolarizing factor (EDHF. In addition, superoxide dismutase (SOD + catalase treatment increased the NO modulation of vasodilator response in methyl-mercury-chloride-exposed rats. Our results demonstrate an increase in the vascular reactivity to ACh in aorta of rats acutely exposed to methyl mercury chloride. Methyl mercury chloride induces nitric oxide synthase (NOS and increases the NO production along with inducing oxidative stress without affecting the EDHF pathway.

Soluble epoxide hydrolase contamination of specific catalase preparations inhibits epoxyeicosatrienoic acid vasodilation of rat renal arterioles

Science.gov (United States)

Olson, Lauren; Harder, Adam; Isbell, Marilyn; Imig, John D.; Gutterman, David D.; Falck, J. R.; Campbell, William B.

2011-01-01

Cytochrome P-450 metabolites of arachidonic acid, the epoxyeicosatrienoic acids (EETs) and hydrogen peroxide (H2O2), are important signaling molecules in the kidney. In renal arteries, EETs cause vasodilation whereas H2O2 causes vasoconstriction. To determine the physiological contribution of H2O2, catalase is used to inactivate H2O2. However, the consequence of catalase action on EET vascular activity has not been determined. In rat renal afferent arterioles, 14,15-EET caused concentration-related dilations that were inhibited by Sigma bovine liver (SBL) catalase (1,000 U/ml) but not Calbiochem bovine liver (CBL) catalase (1,000 U/ml). SBL catalase inhibition was reversed by the soluble epoxide hydrolase (sEH) inhibitor tAUCB (1 μM). In 14,15-EET incubations, SBL catalase caused a concentration-related increase in a polar metabolite. Using mass spectrometry, the metabolite was identified as 14,15-dihydroxyeicosatrienoic acid (14,15-DHET), the inactive sEH metabolite. 14,15-EET hydrolysis was not altered by the catalase inhibitor 3-amino-1,2,4-triazole (3-ATZ; 10–50 mM), but was abolished by the sEH inhibitor BIRD-0826 (1–10 μM). SBL catalase EET hydrolysis showed a regioisomer preference with greatest hydrolysis of 14,15-EET followed by 11,12-, 8,9- and 5,6-EET (Vmax = 0.54 ± 0.07, 0.23 ± 0.06, 0.18 ± 0.01 and 0.08 ± 0.02 ng DHET·U catalase−1·min−1, respectively). Of five different catalase preparations assayed, EET hydrolysis was observed with two Sigma liver catalases. These preparations had low specific catalase activity and positive sEH expression. Mass spectrometric analysis of the SBL catalase identified peptide fragments matching bovine sEH. Collectively, these data indicate that catalase does not affect EET-mediated dilation of renal arterioles. However, some commercial catalase preparations are contaminated with sEH, and these contaminated preparations diminish the biological activity of H2O2 and EETs. PMID:21753077

Optimal decision making and matching are tied through diminishing returns.

Science.gov (United States)

Kubanek, Jan

2017-08-08

How individuals make decisions has been a matter of long-standing debate among economists and researchers in the life sciences. In economics, subjects are viewed as optimal decision makers who maximize their overall reward income. This framework has been widely influential, but requires a complete knowledge of the reward contingencies associated with a given choice situation. Psychologists and ecologists have observed that individuals tend to use a simpler "matching" strategy, distributing their behavior in proportion to relative rewards associated with their options. This article demonstrates that the two dominant frameworks of choice behavior are linked through the law of diminishing returns. The relatively simple matching can in fact provide maximal reward when the rewards associated with decision makers' options saturate with the invested effort. Such saturating relationships between reward and effort are hallmarks of the law of diminishing returns. Given the prevalence of diminishing returns in nature and social settings, this finding can explain why humans and animals so commonly behave according to the matching law. The article underscores the importance of the law of diminishing returns in choice behavior.

On convexity and Schoenberg's variation diminishing splines

International Nuclear Information System (INIS)

Feng, Yuyu; Kozak, J.

1992-11-01

In the paper we characterize a convex function by the monotonicity of a particular variation diminishing spline sequence. The result extends the property known for the Bernstein polynomial sequence. (author). 4 refs

Temporal evolution of vasospasm and clinical outcome after intra-arterial vasodilator therapy in patients with aneurysmal subarachnoid hemorrhage.

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Laleh Daftari Besheli

Full Text Available Intra-arterial (IA vasodilator therapy is one of the recommended treatments to minimize the impact of aneurysmal subarachnoid hemorrhage-induced cerebral vasospasm refractory to standard management. However, its usefulness and efficacy is not well established. We evaluated the effect IA vasodilator therapy on middle cerebral artery blood flow and on discharge outcome. We reviewed records for 115 adults admitted to Neurointensive Care Unit to test whether there was a difference in clinical outcome (discharge mRS in those who received IA infusions. In a subset of 19 patients (33 vessels treated using IA therapy, we tested whether therapy was effective in reversing the trends in blood flow. All measures of MCA blood flow increased from day -2 to -1 before infusion (maximum Peak Systolic Velocity (PSV 232.2±9.4 to 262.4±12.5 cm/s [p = 0.02]; average PSV 202.1±8.5 to 229.9±10.9 [p = 0.02]; highest Mean Flow Velocity (MFV 154.3±8.3 to 172.9±10.5 [p = 0.10]; average MFV 125.5±6.3 to 147.8±9.5 cm/s, [p = 0.02] but not post-infusion (maximum PSV 261.2±14.6 cm/s [p = .89]; average PSV 223.4±11.4 [p = 0.56]; highest MFV 182.9±12.4 cm/s [p = 0.38]; average MFV 153.0±10.2 cm/s [p = 0.54]. After IA therapy, flow velocities were consistently reduced (day X infusion interaction p<0.01 for all measures. However, discharge mRS was higher in IA infusion group, even after adjusting for sex, age, and admission grades. Thus, while IA vasodilator therapy was effective in reversing the vasospasm-mediated deterioration in blood flow, clinical outcomes in the treated group were worse than the untreated group. There is need for a prospective randomized controlled trial to avoid potential confounding effect of selection bias.

Long-term estradiol treatment improves VIP-mediated vasodilation in atherosclerotic proximal coronary arteries

DEFF Research Database (Denmark)

Dalsgaard, T.; Mortensen, Alicja; Larsen, C. R.

2003-01-01

arteries. Female ovariectomized homozygous Watanabe heritable hyperlipidemic rabbits were randomized to 16 weeks treatment with 17beta-estradiol or placebo. The diet was semisynthetic, thereby avoiding the influence of phytoestrogens. Artery ring segments were mounted for isometric tension recordings...... in myographs. Following precontraction, the dose-response relationships for VIP and PACAP were evaluated. Treatment with 17beta-estradiol significantly improved the maximum VIP-mediated vasodilation (E-max, percentage of precontraction) in proximal coronary arteries (45.8 +/- 9.6% vs. 24.1 +/- 3.7%, p ....05). In the same artery segment, 17β-estradiol induced a significant decrease in the relative ratio between the repeated contractile response to potassium 30 and 120 mM (100 +/- 7% vs. 132 +/- 11%, p

Chronotropic response to vasodilator-stress in patients submitted to myocardial perfusion imaging: impact on the accuracy in detecting coronary stenosis

International Nuclear Information System (INIS)

Gimelli, Alessia; Coceani, Michele; Quaranta, Angela; Emdin, Michele; Liga, Riccardo; Marzullo, Paolo

2015-01-01

A lower heart rate response (HRR) during vasodilator MPI has been shown to have a relevant adverse prognostic impact. We sought to evaluate the interaction among individual HRR to vasodilator stress and myocardial perfusion imaging (MPI) accuracy in patients with suspected ischemic heart disease (IHD). One hundred and sixty-five consecutive patients were submitted to vasodilator-stress MPI on a cardiac camera equipped with cadmium-zinc-thelluride detectors and coronary angiography. A coronary stenosis >70 % was considered significant. In every patient, the summed difference score (SDS) was computed from MPI images. Patients were categorized according to the tertiles of the distribution of individual HRR during dipyridamole: ''Group 1'' (HRR < 8 bpm; lowest tertile); ''Group 2'' (8 ≤ HRR ≤ 12 bpm; middle tertile); ''Group 3'' (HRR >12 bpm; highest tertile). Significant coronary artery disease (CAD) was present in 102 (62 %) patients. In the overall population, MPI showed a significant accuracy (AUC: 0.81, 95 % CI 0.74-0.86; p < 0.001) in unmasking the presence of significant coronary stenosis. Interestingly, in patients with a blunted HRR during dipyridamole (''Group 1'') MPI showed a significantly lower sensitivity (68 %) in detecting CAD than in those with a higher HRR (''Group 3'') (91 %, p = 0.007), despite a preserved specificity (76 % vs 77 %, P=NS). Similarly, the correlation among CAD extent and post-stress LV functional stunning was limited to ''Group 3'' patients, while it disappeared in those with blunted HRR. In patients with suspected IHD, MPI sensitivity is strongly influenced by the magnitude of patient heart rate increase to the pharmacologic stressor, suggesting an interaction among blunted HRR and lower accuracy in unmasking CAD. (orig.)

Chronotropic response to vasodilator-stress in patients submitted to myocardial perfusion imaging: impact on the accuracy in detecting coronary stenosis

Energy Technology Data Exchange (ETDEWEB)

Gimelli, Alessia; Coceani, Michele; Quaranta, Angela; Emdin, Michele [Fondazione Toscana Gabriele Monasterio, Pisa (Italy); Liga, Riccardo [University Hospital of Pisa, Cardio-Thoracic and Vascular Department, Pisa (Italy); Marzullo, Paolo [Fondazione Toscana Gabriele Monasterio, Pisa (Italy); CNR, Institute of Clinical Physiology, Pisa (Italy)

2015-11-15

A lower heart rate response (HRR) during vasodilator MPI has been shown to have a relevant adverse prognostic impact. We sought to evaluate the interaction among individual HRR to vasodilator stress and myocardial perfusion imaging (MPI) accuracy in patients with suspected ischemic heart disease (IHD). One hundred and sixty-five consecutive patients were submitted to vasodilator-stress MPI on a cardiac camera equipped with cadmium-zinc-thelluride detectors and coronary angiography. A coronary stenosis >70 % was considered significant. In every patient, the summed difference score (SDS) was computed from MPI images. Patients were categorized according to the tertiles of the distribution of individual HRR during dipyridamole: ''Group 1'' (HRR < 8 bpm; lowest tertile); ''Group 2'' (8 ≤ HRR ≤ 12 bpm; middle tertile); ''Group 3'' (HRR >12 bpm; highest tertile). Significant coronary artery disease (CAD) was present in 102 (62 %) patients. In the overall population, MPI showed a significant accuracy (AUC: 0.81, 95 % CI 0.74-0.86; p < 0.001) in unmasking the presence of significant coronary stenosis. Interestingly, in patients with a blunted HRR during dipyridamole (''Group 1'') MPI showed a significantly lower sensitivity (68 %) in detecting CAD than in those with a higher HRR (''Group 3'') (91 %, p = 0.007), despite a preserved specificity (76 % vs 77 %, P=NS). Similarly, the correlation among CAD extent and post-stress LV functional stunning was limited to ''Group 3'' patients, while it disappeared in those with blunted HRR. In patients with suspected IHD, MPI sensitivity is strongly influenced by the magnitude of patient heart rate increase to the pharmacologic stressor, suggesting an interaction among blunted HRR and lower accuracy in unmasking CAD. (orig.)

Vasodilator Activity of the Essential Oil from Aerial Parts of Pectis brevipedunculata and Its Main Constituent Citral in Rat Aorta

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Gisele Zapata-Sudo

2013-03-01

Full Text Available The essential oil of Pectis brevipedunculata (EOPB, a Brazilian ornamental aromatic grass, is characterized by its high content of citral (81.9%: neral 32.7% and geranial 49.2%, limonene (4.7% and α-pinene (3.4%. Vasodilation induced by EOPB and isolated citral was investigated in pre-contracted vascular smooth muscle, using thoracic aorta from Wistar Kyoto (WKY rats which was prepared for isometric tension recording. EOPB promoted intense relaxation of endothelium-intact and denuded aortic rings with the concentration to induce 50% of the maximal relaxation (IC50 of 0.044% ± 0.006% and 0.093% ± 0.015% (p 0.05. In endothelium-intact aorta, EOPB-induced vasorelaxation was significantly reduced by L-NAME, a nitric oxide synthase inhibitor. The vasodilator activity of citral was increased in the KCl-contracted aorta and citral attenuated the contracture elicited by Ca2+ in depolarized aorta. EOPB and citral elicited vasorelaxation on thoracic aorta by affecting the NO/cyclic GMP pathway and the calcium influx through voltage-dependent L-type Ca2+ channels, respectively.

Vasodilator activity of the essential oil from aerial parts of Pectis brevipedunculata and its main constituent citral in rat aorta.

Science.gov (United States)

Pereira, Sharlene Lopes; Marques, André Mesquita; Sudo, Roberto Takashi; Kaplan, Maria Auxiliadora Coelho; Zapata-Sudo, Gisele

2013-03-07

The essential oil of Pectis brevipedunculata (EOPB), a Brazilian ornamental aromatic grass, is characterized by its high content of citral (81.9%: neral 32.7% and geranial 49.2%), limonene (4.7%) and α-pinene (3.4%). Vasodilation induced by EOPB and isolated citral was investigated in pre-contracted vascular smooth muscle, using thoracic aorta from Wistar Kyoto (WKY) rats which was prepared for isometric tension recording. EOPB promoted intense relaxation of endothelium-intact and denuded aortic rings with the concentration to induce 50% of the maximal relaxation (IC50) of 0.044% ± 0.006% and 0.093% ± 0.015% (p 0.05). In endothelium-intact aorta, EOPB-induced vasorelaxation was significantly reduced by L-NAME, a nitric oxide synthase inhibitor. The vasodilator activity of citral was increased in the KCl-contracted aorta and citral attenuated the contracture elicited by Ca2+ in depolarized aorta. EOPB and citral elicited vasorelaxation on thoracic aorta by affecting the NO/cyclic GMP pathway and the calcium influx through voltage-dependent L-type Ca2+ channels, respectively.

Awe, the diminished self, and collective engagement: Universals and cultural variations in the small self.

Science.gov (United States)

Bai, Yang; Maruskin, Laura A; Chen, Serena; Gordon, Amie M; Stellar, Jennifer E; McNeil, Galen D; Peng, Kaiping; Keltner, Dacher

2017-08-01

Awe has been theorized as a collective emotion, one that enables individuals to integrate into social collectives. In keeping with this theorizing, we propose that awe diminishes the sense of self and shifts attention away from individual interests and concerns. In testing this hypothesis across 6 studies (N = 2137), we first validate pictorial and verbal measures of the small self; we then document that daily, in vivo, and lab experiences of awe, but not other positive emotions, diminish the sense of the self. These findings were observed across collectivist and individualistic cultures, but also varied across cultures in magnitude and content. Evidence from the last 2 studies showed that the influence of awe upon the small self accounted for increases in collective engagement, fitting with claims that awe promotes integration into social groups. Discussion focused on how the small self might mediate the effects of awe on collective cognition and behavior, the need to study more negatively valenced varieties of awe, and other potential cultural variations of the small self. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Reconciling the Mitscherlich's law of diminishing returns with Liebig's law of the minimum. Some results on crop modeling.

Science.gov (United States)

Ferreira, Iuri E P; Zocchi, Silvio S; Baron, Daniel

2017-11-01

Reliable fertilizer recommendations depend on the correctness of the crop production models fitted to the data, but generally the crop models are built empirically, neglecting important physiological aspects related with response to fertilizers, or they are based in laws of plant mineral nutrition seen by many authors as conflicting theories: the Liebig's Law of the Minimum and Mitscherlich's Law of Diminishing Returns. We developed a new approach to modelling the crop response to fertilizers that reconcile these laws. In this study, the Liebig's Law is applied at the cellular level to explain plant production and, as a result, crop models compatible with the Law of Diminishing Returns are derived. Some classical crop models appear here as special cases of our methodology, and a new interpretation for Mitscherlich's Law is also provided. Copyright © 2017 Elsevier Inc. All rights reserved.

Vasodilator effects and putative guanylyl cyclase stimulation by 2-nitro-1-phenylethanone and 2-nitro-2-phenyl-propane-1,3-diol on rat aorta.

Science.gov (United States)

Vasconcelos, Thiago Brasileiro de; Ribeiro-Filho, Helder Veras; Lahlou, Saad; Pereira, José Geraldo de Carvalho; Oliveira, Paulo Sérgio Lopes de; Magalhães, Pedro Jorge Caldas

2018-07-05

Compounds containing a nitro group may reveal vasodilator properties. Several nitro compounds have a NO 2 group in a short aliphatic chain connected to an aromatic group. In this study, we evaluated in rat aorta the effects of two nitro compounds, with emphasis on a putative recruitment of the soluble guanylate cyclase (sGC) pathway to induce vasodilation. Isolated aortic rings were obtained from male Wistar rats to compare the effects induced by 2-nitro-1-phenylethanone (NPeth) or 2-nitro-2-phenyl-propane-1,3-diol (NPprop). In aortic preparations contracted with phenylephrine or KCl, NPeth and NPprop induced vasorelaxant effects that did not depend on the integrity of vascular endothelium. NPeth had a lesser vasorelaxant efficacy than NPprop and only the NPprop effects were inhibited by pretreatment with the sGC inhibitors, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) or methylene blue. In an ODQ-preventable manner, NPprop inhibited the contractile component of the phenylephrine-induced response mediated by intracellular Ca 2+ release or by extracellular Ca 2+ recruitment through receptor- or voltage-operated Ca 2+ channels. In contrast, NPprop was inert against the transient contraction induced by caffeine in Ca 2+ -free medium. In an ODQ-dependent manner, NPprop inhibited the contraction induced by the protein kinase C activator phorbol 12,13-dibutyrate or by the tyrosine phosphatase inhibitor sodium orthovanadate. In silico docking analysis of a sGC homologous protein revealed preferential site for NPprop. In conclusion, the nitro compounds NPeth and NPprop induced vasorelaxation in rat aortic rings. Aliphatic chain substituents selectively interfered in the ability of these compounds to induce vasorelaxant effects, and only NPprop relaxed aortic rings via a sGC pathway. Copyright © 2018 Elsevier B.V. All rights reserved.

EFFICACY OF REMAXOL AND ADEMETHIONINE IN EXPERIMENTAL LIVER DAMAGE CAUSED BY A COMBINATION OF RESERVE-SERIES ANTITUBERCULOSIS DRUGS AND ALCOHOL

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D. S. Sukhanov

2014-01-01

Full Text Available The hepatic and endothelial protective effects of remaxol and S-adenosyl-L-methionine were studied on 24 male rats with liver damage caused by reserve-series antituberculosis drugs in combination with alcohol. The test agents were found to have a unilateral hepatoprotective effect in decreasing the blood levels of triglycerides, bilirubin, and alkaline phosphatase with a concurrent significant reduction in the manifestations of hyaline-drop and hydropic dystrophy of hepatocytes. Remaxol and ademethionine have the same endothelial protective activity manifested as normalization of an endothelium-dependent vasodilation response and endothelial dysfunction coefficient.

The problem of social exclusion diminishing in the context of European parliament recommendations

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Arvydas

2015-12-01

Full Text Available European Parliament is one of the most significant EU institutions which are responsible for the tasks of social dimension‘s aims declaration and implementation. One of the most actual tasks, solved by European Parliament, is social security measures fitness to real minimal subsistence level and social inequality and exclusion diminishing in the member states. Strengthening of social dimension and lessening of social exclusion can also suffer from economic difficulties, which appeared in the member states after 2008–2009 economic crisis – when there is still no breaking with the crisis past and the new downfall is still possible. In the article the impact of crisis for social exclusion diminishing is analyzed in the context of European Parliament recommendations. Social security measures had only limited impact for stabilization in the member states, however, the author argues and the European Parliament documents prove, that social security measures are not the burden, but the reserve for development in the member states. In this case, European Parliament together with International Labour Organization, according the author, are the most socially exposed organizations in the world. In the end of the article there is suggested the significant social reintegration indicator for the measurement of social security‘s efficiency and effectiveness.

Jabuticaba-Induced Endothelium-Independent Vasodilating Effect on Isolated Arteries

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Daniela Medeiros Lobo de Andrade

2016-01-01

Full Text Available Abstract Background: Despite the important biological effects of jabuticaba, its actions on the cardiovascular system have not been clarified. Objectives: To determine the effects of jabuticaba hydroalcoholic extract (JHE on vascular smooth muscle (VSM of isolated arteries. Methods: Endothelium-denuded aortic rings of rats were mounted in isolated organ bath to record isometric tension. The relaxant effect of JHE and the influence of K+ channels and Ca2+ intra- and extracellular sources on JHE-stimulated response were assessed. Results: Arteries pre-contracted with phenylephrine showed concentration-dependent relaxation (0.380 to 1.92 mg/mL. Treatment with K+ channel blockers (tetraethyl-ammonium, glibenclamide, 4-aminopyridine hindered relaxation due to JHE. In addition, phenylephrine-stimulated contraction was hindered by previous treatment with JHE. Inhibition of sarcoplasmic reticulum Ca2+ ATPase did not change relaxation due to JHE. In addition, JHE inhibited the contraction caused by Ca2+ influx stimulated by phenylephrine and KCl (75 mM. Conclusion: JHE induces endothelium-independent vasodilation. Activation of K+ channels and inhibition of Ca2+ influx through the membrane are involved in the JHE relaxant effect.

The Role of Vasodilator Receptors of Renin-angiotensin System on Nitric Oxide Formation and Kidney Circulation after Angiotensin II Infusion in Renal Ischemia/Reperfusion Rats.

Science.gov (United States)

Maleki, Maryam; Hasanshahi, Jalal; Moslemi, Fatemeh

2018-01-01

Nitric oxide (NO) as a vasodilator factor has renoprotective effect against renal ischemia. The balance between angiotensin II (Ang II) and NO can affect kidney homeostasis. The aim of this study was to determine NO alteration in response to renin-Ang system vasodilator receptors antagonists (PD123319; Ang II type 2 receptor antagonist and A779; Mas receptor antagonist) in renal ischemia/reperfusion injury (IRI) in rats. Sixty-three Wistar male and female rats were used. Animals from each gender were divided into four groups received saline, Ang II, PD123319 + Ang II, and A779 + Ang II after renal IRI. Renal IRI induced with an adjustable hook. Blood pressure and renal blood flow (RBF) measured continuously. The nitrite levels were measured in serum, kidney, and urine samples. In female rats, the serum and kidney nitrite levels increased significantly by Ang II ( P < 0.05) and decreased significantly ( P < 0.05) when PD123319 was accompanied with Ang II. Such observation was not seen in male. Ang II decreased RBF significantly in all groups ( P < 0.05), while PD + Ang II group showed significant decrease in RBF in comparison with the other groups in female rats ( P < 0.05). Males show more sensibility to Ang II infusion; in fact, it is suggested that there is gender dimorphism in the Ang II and NO production associated with vasodilator receptors.

Environmental and developmental origins of ovarian reserve.

Science.gov (United States)

Richardson, M C; Guo, M; Fauser, B C J M; Macklon, N S

2014-01-01

BACKGROUND Oocyte number is established early in life before a gradual loss of this ovarian reserve during reproductive life until oocyte availability becomes limiting at the menopause. Although there is a large genetic component to the ovarian reserve achieved before birth, other influences including the maternal endocrine and nutritional milieu, and environmental factors may represent important developmental determinants. Environmental and nutritional factors may also modify the downward trajectory of ovarian reserve in adult life. The combination of these early and later life influences has the potential to lead to diminished ovarian reserve, compromising fertility in later reproductive years and altering age at natural menopause. METHODS Literature searches of the ISI Web of Knowledge database were carried out using the main terms 'ovarian reserve' and 'menopause AND age' in conjunction with a range of other terms encompassing a variety of factors with potential effects on ovarian reserve. The various searches were inspected manually and the relevant papers selected for critical analysis and interpretation. RESULTS Evidence was identified supporting the view that elevated prenatal androgens have an adverse effect on the early establishment of ovarian reserve, although the implications for ovarian reserve in the polycystic ovary syndrome (which may also be programmed through prenatal androgen exposure) remain uncertain. Recent evidence is cited suggesting that effects of maternal nutrient restriction on ovarian reserve may also involve changes in prenatal androgen exposure. A general rationale is developed through examination of evidence which emphasizes the roles of the aryl hydrocarbon receptor (AHR) and the estrogen receptor (ER) systems in ovarian reserve modulation. Because of their similarity to the natural ligands, many environmental compounds have the ability to bind to these receptors (albeit at lower affinities) and thereby have the potential to

Lhe law of diminishing elasticity of demand in Harrod’s trade cycle

OpenAIRE

Michaël Assous; Olivier Bruno; Muriel Dal-Pont

2014-01-01

In The Trade Cycle, Roy Harrod [1936a] propounded the Law of Diminishing Elasticity of Demand. The present paper tries to clarify the precise role Harrod assigned to this law in his The Trade Cycle Theory. We discuss the micro and macro foundations of the Law of Diminishing Elasticity of Demand and argue that it explains one of the main mechanisms that stabilize the economy during the trade cycle. In addition, we highlight how the Law of Diminishing Elasticity of Demand allowed Harrod to micr...

Determinants of the response of left ventricular ejection fraction to vasodilator stress in electrocardiographically gated {sup 82}rubidium myocardial perfusion PET

Energy Technology Data Exchange (ETDEWEB)

Brown, Tracy L.Y.; Merrill, Jennifer; Bengel, Frank M. [Johns Hopkins University, Department of Radiology and Radiological Sciences, Division of Nuclear Medicine, Baltimore, MD (United States); Volokh, Lana [GE Healthcare, Haifa (Israel)

2008-02-15

Myocardial perfusion imaging with {sup 82}Rb PET allows for ECG-gated studies to be obtained early after radiotracer injection, capturing ventricular function close to peak pharmacologic action of dipyridamole. This is different from gated SPECT and may potentially provide additional diagnostic information. We sought to identify potential correlates of the PET-derived ejection fraction response to vasodilator stress. One hundred ten consecutive patients undergoing {sup 82}Rb PET myocardial perfusion imaging during evaluation for coronary artery disease were included. Using a GE Discovery STRx PET-CT scanner, ECG-gated images (eight bins) were obtained at rest and 4 min after dipyridamole infusion, 90 s after infusion of 1,480-2,220 MBq of {sup 82}Rb. Summed rest, stress, and difference scores (SRS, SSS, and SDS) were determined using a five-point scoring system and 20-segment model. Ejection fraction was calculated using automated QGS software. Significant reversibility (SDS {>=} 4) was found in 23 patients (21%). Mean LVEF in all patients was 47 {+-} 13% at rest and 53 {+-} 13% during dipyridamole. LVEF increased in 89 patients, and decreased in 17 patients during vasodilation. The change in LVEF was inversely correlated with SDS (r = -0.26; p = 0.007). Additionally, it was inversely correlated with resting LVEF (r = -0.20; p = 0.03) and SSS (r = -0.25; p = 0.009). No significant correlations were observed with SRS, heart rate, blood pressure, age, hypertension, hypercholesterolemia, or pretest likelihood of disease. At multivariate regression analysis, SDS was an independent predictor of the change in LVEF. Gated {sup 82}Rb PET during pharmacologic stress allows for assessment of the functional response to vasodilation. The magnitude of LVEF increase is determined by stress perfusion/reversible perfusion defects. Functional response to hyperemia may thus be incorporated in future evaluations of diagnostic and prognostic algorithms based on {sup 82}Rb PET. (orig.)

Differential Changes of Aorta and Carotid Vasodilation in Type 2 Diabetic GK and OLETF Rats: Paradoxical Roles of Hyperglycemia and Insulin

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Mei-Fang Zhong

2012-01-01

Full Text Available We investigated large vessel function in lean Goto-Kakizaki diabetic rats (GK and Otsuka Long-Evans Tokushima Fatty diabetic rats (OLETF with possible roles of hyperglycemia/hyperosmolarity and insulin. Both young and old GK showed marked hyperglycemia with normal insulin level and well-preserved endothelium-dependent and endothelium-independent vasodilation in aorta and carotid artery. There were significant elevations in endothelial/inducible nitric oxide synthase (eNOS/iNOS and inducible/constitutive heme oxygenase (HO-1/HO-2 in GK. The endothelium-dependent vasodilation in GK was inhibited partly by NOS blockade and completely by simultaneous blocking of HO and NOS. In contrast, OLETF showed hyperinsulinemia and mild hyperglycemia but significant endothelium dysfunction beginning at early ages with concomitantly reduced eNOS. Insulin injection corrected hyperglycemia in GK but induced endothelium dysfunction and intima hyperplasia. Hyperglycemia/hyperosmolarity in vitro enhanced vessel eNOS/HO. We suggest that hyperinsulinemia plays a role in endothelium dysfunction in obese diabetic OLETF, while hyperglycemia/hyperosmolarity-induced eNOS/HO upregulation participates in the adaptation of endothelium function in lean diabetic GK.

Intensive short-term vasodilation effect in the pain area of sciatica patients--case study.

Science.gov (United States)

Skorupska, Elżbieta; Rychlik, Michał; Pawelec, Wiktoria; Bednarek, Agata; Samborski, Włodzimierz

2014-09-09

Varied and complicated etiology of low back pain radiating distally to the extremities is still causing disagreement and controversy around the issue of its diagnosis and treatment. Most clinicians believe that the source of that pain is generally radicular. While some of them postulate the clinical significance of the sacroiliac joint syndrome, others demonstrate that almost one in five people with back pain experience symptoms indicative of the neuropathic pain component. To date, neuropathic involvement has not been completely understood, and different mechanisms are thought to play an important role. It has been established that muscle pain (myofascial pain) e.g. active trigger points from the gluteus minimus, can mimic pain similar to sciatica, especially in the chronic stage. This paper describes patients presenting with radicular sciatica (case one and two) and sciatica-like symptoms (case three). For the first time, intensive short-term vasodilation in the pain area following needle infiltration of the gluteus minimus trigger point was recorded. Three Caucasian, European women suffering from radicular sciatica (case one and two) and sciatica-like symptoms (case three) at the age of 57, 49 and 47 respectively underwent infrared camera observation during needle infiltration of the gluteus minimus trigger point. The patients were diagnosed by a neurologist; they underwent magnetic resonance imaging, electromyography, neurography and blood test analysis. Apart from that, the patients were diagnosed by a clinician specializing in myofascial pain diagnosis. In the examined cases, trigger points-related short-term vasodilation was recorded. Confirmation of these findings in a controlled, blinded study would indicate the existence of a link between the pain of sciatica patients (radicular or sciatica-like pain) and the activity of the autonomic nervous system. Further studies on a bigger group of patients are still needed.

Role of protein sulfation in vasodilation induced by minoxidil sulfate, a K+ channel opener

International Nuclear Information System (INIS)

Meisheri, K.D.; Oleynek, J.J.; Puddington, L.

1991-01-01

Evidence from contractile, radioisotope ion flux and electrophysiological studies suggest that minoxidil sulfate (MNXS) acts as a K+ channel opener in vascular smooth muscle. This study was designed to examine possible biochemical mechanisms by which MNXS exerts such an effect. Experiments performed in the isolated rabbit mesenteric artery (RMA) showed that MNXS, 5 microM, but not the parent compound minoxidil, was a potent vasodilator. Whereas the relaxant effects of an another K+ channel opener vasodilator, BRL-34915 (cromakalim), were removed by washing with physiological saline solution, the effects of MNXS persisted after repeated washout attempts. Furthermore, after an initial exposure of segments of intact RMA to [35S] MNXS, greater than 30% of the radiolabel was retained 2 hr after removal of the drug. In contrast, retention of radiolabel was not detected with either [3H]MNXS (label on the piperidine ring of MNXS) or [3H]minoxidil (each less than 3% after a 2-hr washout). These data suggested that the sulfate moiety from MNXS was closely associated with the vascular tissue. To determine if proteins were the acceptors of sulfate from MNXS, intact RMAs were incubated with [35S]MNXS, and then 35S-labeled proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and analyzed by fluorography. Preferential labeling of a 116 kD protein was detected by 2 and 5 min of treatment. A 43 kD protein (resembling actin) also showed significant labeling. A similar profile of 35S-labeled proteins was observed in [35S] MNXS-treated A7r5 rat aortic smooth muscle cells, suggesting that the majority of proteins labeled by [35S]MNXS in intact RMA were components of smooth muscle cells

Functional pulmonary atresia in newborn with normal intracardiac anatomy: Successful treatment with inhaled nitric oxide and pulmonary vasodilators

Directory of Open Access Journals (Sweden)

Gürkan Altun

2013-01-01

Full Text Available Functional pulmonary atresia is characterized by a structurally normal pulmonary valve that does not open during right ventricular ejection. It is usually associated with Ebstein′s anomaly, Uhl′s anomaly, neonatal Marfan syndrome and tricuspid valve dysplasia. However, functional pulmonary atresia is rarely reported in newborn with anatomically normal heart. We report a newborn with functional pulmonary atresia who had normal intracardiac anatomy, who responded to treatment with nitric oxide and other vasodilator therapy successfully.

Black tea and maintenance of normal endotheliumdependent vasodilation: evaluation of a health claim pursuant to Article 13(5) of Regulation (EC) No 1924/2006

DEFF Research Database (Denmark)

Sjödin, Anders Mikael

2018-01-01

on the scientific substantiation of a health claim related to black tea and maintenance of normal endotheliumdependent vasodilation. The scope of the application was proposed to fall under a health claim based on newly developed scientific evidence. The food proposed by the applicant as the subject of the health...... claim is black tea beverages, either freshly prepared or reconstituted from water extract powders of black tea, characterised by the content of flavanols (expressed as catechins plus theaflavins) of at least 30 mg per 200 mL serving. The Panel considers that black tea characterised by the content....... Of the five human intervention studies provided on the chronic effect of black tea consumption on endothelium-dependent vasodilation, two investigated the effect after regular consumption of black tea for a sufficiently long time period (i.e. at least 4 weeks). These two studies did not allow an effect...

Prognostic value of vasodilator response using rubidium-82 positron emission tomography myocardial perfusion imaging in patients with coronary artery disease

Energy Technology Data Exchange (ETDEWEB)

Arasaratnam, Punitha; Sadreddini, Masoud; Yam, Yeung; Kansal, Vinay; Beanlands, Rob S. [University of Ottawa Heart Institute, Canada, Department of Medicine (Cardiology), Ottawa, ON (Canada); Dorbala, Sharmila; Di Carli, Marcelo F. [Brigham and Women' s Hospital, Division of Cardiovascular Medicine and Division of Nuclear Medicine, Boston, MA (United States); Merhige, Michael E. [Niagara Falls Memorial Medical Center, Departments of Cardiology, Internal Medicine, and Nuclear Medicine, Buffalo, NY (United States); Williams, Brent A. [Geisinger Medical Center, Department of Center for Health Research, Danville, PA (United States); Veledar, Emir; Shaw, Leslee J. [Emory University School of Medicine, Department of Medicine, Atlanta, GA (United States); Min, James K. [Weill Cornell Medical College, Department of Radiology and Department of Imaging, New York, NY (United States); Chen, Li [University of Ottawa Heart Institute, Cardiovascular Research Methods Centre, Ottawa, ON (Canada); Ruddy, Terrence D.; Chow, Benjamin J.W. [University of Ottawa Heart Institute, Canada, Department of Medicine (Cardiology), Ottawa, ON (Canada); University of Ottawa, Department of Radiology, Ottawa, ON (Canada); Germano, Guido; Berman, Daniel S. [Cedars-Sinai Medical Center, Department of Imaging, Los Angeles, CA (United States)

2018-04-15

Prognostic value of positron emission tomography (PET) myocardial perfusion imaging (MPI) is well established. There is paucity of data on how the prognostic value of PET relates to the hemodynamic response to vasodilator stress. We hypothesize that inadequate hemodynamic response will affect the prognostic value of PET MPI. Using a multicenter rubidium (Rb)-82 PET registry, 3406 patients who underwent a clinically indicated rest/stress PET MPI with a vasodilator agent were analyzed. Patients were categorized as, ''responders'' [increase in heart rate ≥ 10 beats per minute (bpm) and decrease in systolic blood pressure (SBP) ≥10 mmHg], ''partial responders'' (either a change in HR or SBP), and ''non-responders'' (no change in HR or SBP). Primary outcome was all-cause death (ACD), and secondary outcome was cardiac death (CD). Ischemic burden was measured using summed stress score (SSS) and % left ventricular (LV) ischemia. After a median follow-up of 1.68 years (interquartile range = 1.17- 2.55), there were 7.9% (n = 270) ACD and 2.6% (n = 54) CD. Responders with a normal PET MPI had an annualized event rate (AER) of 1.22% (SSS of 0-3) and 1.58% (% LV ischemia = 0). Partial and non-responders had higher AER with worsening levels of ischemic burden. In the presence of severe SSS ≥12 and LV ischemia of ≥10%, partial responders had an AER of 10.79% and 10.36%, compared to non-responders with an AER of 19.4% and 12.43%, respectively. Patient classification was improved when SSS was added to a model containing clinical variables (NRI: 42%, p < 0.001) and responder category was added (NRI: 61%, p < 0.001). The model including clinical variables, SSS and hemodynamic response has good discrimination ability (Harrell C statistics: 0.77 [0.74-0.80]). Hemodynamic response during a vasodilator Rb-82 PET MPI is predictive of ACD. Partial and non-responders may require additional risk stratification leading to

Assessment of inotropic and vasodilating effects of milrinone lactate in patients with dilated cardiomyopathy and severe heart failure

Directory of Open Access Journals (Sweden)

Edson Antonio Bregagnollo

1999-02-01

Full Text Available OBJECTIVE: To assess the hemodynamic and vasodilating effects of milrinone lactate (ML in patients with dilated cardiomyopathy (DCM and New York Heart Association (NYHA class III and IV heart failure. METHODS: Twenty patients with DCM and NYHA class III and IV heart failure were studied. The hemodynamic and vasodilating effects of ML, administered intravenously, were evaluated. The following variables were compared before and during drug infusion: cardiac output (CO and cardiac index (CI; pulmonary capillary wedge pressure (PCWP; mean aortic pressure (MAP; mean pulmonary artery pressure (MPAP; mean right atrial pressure (MRAP; left ventricular systolic and end-diastolic pressures (LVSP and LVEDP, respectively; peak rate of left ventricular pressure rise (dP/dt; systemic vascular resistance (SVR; pulmonary vascular resistance (PVR; and heart rate (HR. RESULTS: All patients showed a significant improvement of the analysed parameters of cardiac performance with an increase of CO and CI; a significant improvement in myocardial contractility (dP/dt and reduction of the LVEDP; PCWP; PAP; MAP; MRAP; SVR; PVR. Were observed no significant increase in HR occurred. CONCLUSION: Milrinone lactate is an inotropic dilating drug that, when administered intravenously, has beneficial effects on cardiac performance and myocardial contractility. It also promotes reduction of SVR and PVR in patients with DCM and NYHA class III and IV of heart failure.

Comparison of the vasodilator responses of isolated human and rat middle meningeal arteries to migraine related compounds

DEFF Research Database (Denmark)

Grände, Gustaf; Labruijere, Sieneke; Haanes, Kristian Agmund

2014-01-01

, telcagepant) were applied to the isolated arteries, and both induced a significant decrease of the effect of exogenously administrated CGRP. In experiments on rat middle meningeal arteries, pre-contracted with PGF2α, similar tendencies were seen. When the pre-contraction was switched to K+ in a separate...... series of experiments, CGRP and sildenafil significantly relaxed the arteries. CONCLUSIONS: Still no definite answer can be given as to why pain is experienced during an attack of migraine. No clear correlation was found between the efficacy of a substance as a meningeal artery vasodilator in human...

Differences between negative inotropic and vasodilator effects of calcium antagonists acting on extra- and intracellular calcium movements in rat and guinea-pig cardiac preparations

NARCIS (Netherlands)

Hugtenburg, J. G.; Mathy, M. J.; Boddeke, H. W.; Beckeringh, J. J.; van Zwieten, P. A.

1989-01-01

In order to get more insight into the utilization of calcium in the mammalian heart and the influence of calcium antagonists on this process we have evaluated the negative inotropic and vasodilator effect of nifedipine, diltiazem, verapamil, bepridil and lidoflazine as well as of the intracellularly

The Law of Diminishing Elasticity of Demand in Harrod’s Trade Cycle (1936)

OpenAIRE

Michaël Assous; Olivier Bruno; Muriel Dal-Pont Legrand

2015-01-01

In The Trade Cycle, Roy Harrod [1936a] propounded the Law of Diminishing Elasticity of Demand. The present paper tries to clarify the precise role Harrod assigned to this law in order to understand his trade cycle theory. We discuss the micro and macro foundations of the Law of Diminishing Elasticity of Demand and how, according to Harrod, it explains one of the main mechanisms that stabilize the economy during the trade cycle. In addition, we show how the Law of Diminishing Elasticity of Dem...

Effects of sapropterin on endothelium-dependent vasodilation in patients with CADASIL: a randomized controlled trial.

Science.gov (United States)

De Maria, Renata; Campolo, Jonica; Frontali, Marina; Taroni, Franco; Federico, Antonio; Inzitari, Domenico; Tavani, Alessandra; Romano, Silvia; Puca, Emanuele; Orzi, Francesco; Francia, Ada; Mariotti, Caterina; Tomasello, Chiara; Dotti, Maria Teresa; Stromillo, Maria Laura; Pantoni, Leonardo; Pescini, Francesca; Valenti, Raffaella; Pelucchi, Claudio; Parolini, Marina; Parodi, Oberdan

2014-10-01

Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a rare autosomal dominant disorder caused by NOTCH3 mutations, is characterized by vascular smooth muscle and endothelial cells abnormalities, altered vasoreactivity, and recurrent lacunar infarcts. Vasomotor function may represent a key factor for disease progression. Tetrahydrobiopterin, essential cofactor for nitric oxide synthesis in endothelial cells, ameliorates endothelial function. We assessed whether supplementation with sapropterin, a synthetic tetrahydrobiopterin analog, improves endothelium-dependent vasodilation in CADASIL patients. In a 24-month, multicenter randomized, double-blind, placebo-controlled trial, CADASIL patients aged 30 to 65 years were randomly assigned to receive placebo or sapropterin 200 to 400 mg BID. The primary end point was change in the reactive hyperemia index by peripheral arterial tonometry at 24 months. We also assessed the safety and tolerability of sapropterin. Analysis was done by intention-to-treat. The intention-to-treat population included 61 patients. We found no significant difference between sapropterin (n=32) and placebo (n=29) in the primary end point (mean difference in reactive hyperemia index by peripheral arterial tonometry changes 0.19 [95% confidence interval, -0.18, 0.56]). Reactive hyperemia index by peripheral arterial tonometry increased after 24 months in 37% of patients on sapropterin and in 28% on placebo; however, after adjustment for age, sex, and clinical characteristics, improvement was not associated with treatment arm. The proportion of patients with adverse events was similar on sapropterin and on placebo (50% versus 48.3%); serious adverse events occurred in 6.3% versus 13.8%, respectively. Sapropterin was safe and well-tolerated at the average dose of 5 mg/kg/day, but did not affect endothelium-dependent vasodilation in CADASIL patients. https://www.clinicaltrialsregister.eu. Unique

Liposomal Fasudil, a Rho-Kinase Inhibitor, for Prolonged Pulmonary Preferential Vasodilation in Pulmonary Arterial Hypertension

Science.gov (United States)

Gupta, Vivek; Gupta, Nilesh; Shaik, Imam H.; Mehvar, Reza; McMurtry, Ivan F.; Oka, Masahiko; Nozik-Grayck, Eva; Komatsu, Masanobu; Ahsan, Fakhrul

2013-01-01

Current pharmacological interventions for pulmonary arterial hypertension (PAH) require continuous infusions, multiple inhalations, or oral administration of drugs that act on various pathways involved in the pathogenesis of PAH. However, invasive methods of administration, short duration of action, and lack of pulmonary selectivity result in noncompliance and poor patient outcomes. In this study, we tested the hypothesis that encapsulation of an investigational anti-PAH molecule fasudil (HA-1077), a Rho-kinase inhibitor, into liposomal vesicles results in prolonged vasodilation in distal pulmonary arterioles. Liposomes were prepared by hydration and extrusion method and fasudil was loaded by ammonium sulfate-induced transmembrane electrochemical gradient. Liposomes were then characterized for various physicochemical properties. Optimized formulations were tested for pulmonary absorption and their pharmacological efficacy in a monocrotaline (MCT) induced rat model of PAH. The entrapment efficiency of optimized liposomal fasudil formulations was between 68.1±0.8% and 73.6±2.3%, and the cumulative release at 37°C was 98–99% over a period of 5 days. Compared to intravenous (IV) fasudil, a ~10 fold increase in the terminal plasma half-life was observed when liposomal fasudil was administered as aerosols. The t1/2 of IV fasudil was 0.39±0.12 h. and when given as liposomes via pulmonary route, the t1/2 extended to 4.71±0.72 h. One h after intratracheal instillation of liposomal fasudil, mean pulmonary arterial pressure (MPAP) was reduced by 37.6±5.7% and continued to decrease for about 3 h, suggesting that liposomal formulations produced pulmonary preferential vasodilation in MCT induced PAH rats. Overall, this study established the proof-of-principle that aerosolized liposomal fasudil is a feasible option for a non-invasive, controlled release and pulmonary preferential treatment of PAH. PMID:23353807

Elements to diminish radioactive accidents

International Nuclear Information System (INIS)

Cortes I, M.E.; Ramirez G, F.P.

1998-01-01

In this work it is presented an application of the cause-effect diagram method or Ichikawa method identifying the elements that allow to diminish accidents when the radioactive materials are transported. It is considered the transport of hazardous materials which include radioactive materials in the period: December 1996 until March 1997. Among the identified elements by this method it is possible to mention: the road type, the radioactive source protection, the grade driver responsibility and the preparation that the OEP has in the radioactive material management. It is showed the differences found between the country inner roads and the Mexico City area. (Author)

Acute hemodynamic response to vasodilators in primary pulmonary hypertension.

Directory of Open Access Journals (Sweden)

Kulkarni H

1996-01-01

Full Text Available Acute hemodynamic effects of high flow oxygen (O2 inhalation, sublingual isosorbide dinitrate (ISDN, intravenous aminophylline (AMN and sublingual nifedipine (NIF were studied in 32 patients with primary pulmonary hypertension (PPH. In 30 out of 32 patients the basal ratio of pulmonary to systemic vascular resistance (Rp/Rs was > 0.5 (mean = 0.77 +/- 0.20. Oxygen caused significant decrease in the mean resistance ratio to 0.68 +/- 0.20 (p = 0.005. ISDN, AMN and NIF caused increase in the resistance ratio to 0.79 +/- 0.26; 0.78 +/- 0.26; and 0.80 +/- 0.23 respectively. O2, ISDN, AMN and NIF caused a fall of Rp/Rs in 21 (65.6%, 10 (31.2%, 10(31.2% and 9(28.1% patients respectively. Thus, of the four drugs tested high flow O2 inhalation resulted in fall of Rp/Rs in two thirds of patients whereas ISDN, AMN and NIF caused a mean rise in Rp/Rs. One third of patients did respond acutely to the latter three drugs. Acute hemodynamic studies are useful before prescribing vasodilators in patients with PPH since more of the commonly used drugs like ISDN, AMN, NIF could have detrimental hemodynamic responses in some patients. However, great caution should be exercised before performing hemodynamic study as the procedure has definite mortality and morbidity.

Generation of nitric oxide from nitrite by carbonic anhydrase: a possible link between metabolic activity and vasodilation

DEFF Research Database (Denmark)

Aamand, Rasmus; Dalsgaard, Thomas; Jensen, Frank Bo

2009-01-01

In catalyzing the reversible hydration of CO2 to bicarbonate and protons, the ubiquitous enzyme carbonic anhydrase (CA) plays a crucial role in CO2 transport, in acid-base balance, and in linking local acidosis to O2 unloading from hemoglobin. Considering the structural similarity between...... bicarbonate and nitrite, we hypothesized that CA uses nitrite as a substrate to produce the potent vasodilator nitric oxide (NO) to increase local blood flow to metabolically active tissues. Here we show that CA readily reacts with nitrite to generate NO, particularly at low pH, and that the NO produced...

EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of a health claim related to cocoa flavanols and maintenance of normal endothelium-dependent vasodilation pursuant to Article 13(5) of Regulation (EC) No 1924/2006

DEFF Research Database (Denmark)

Tetens, Inge

Following an application from Barry Callebaut Belgium nv, submitted pursuant to Article 13(5) of Regulation (EC) No 1924/2006 via the Competent Authority of Belgium, the Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on the scientific substantiation...... of a health claim related to cocoa flavanols and maintenance of normal endothelium-dependent vasodilation. Cocoa flavanols are sufficiently characterised. The claimed effect is “help maintain endothelium-dependent vasodilation which contributes to healthy blood flow”. The target population proposed...... by the applicant is the general healthy adult population. The Panel considers that maintenance of normal endothelium-dependent vasodilation is a beneficial physiological effect. In weighing the evidence, the Panel took into account that cocoa flavanols consumed for 12 weeks have been shown to increase fasting ED...

Treatment of spontaneously hypertensive rats with rosiglitazone and/or enalapril restores balance between vasodilator and vasoconstrictor actions of insulin with simultaneous improvement in hypertension and insulin resistance.

Science.gov (United States)

Potenza, Maria A; Marasciulo, Flora L; Tarquinio, Mariela; Quon, Michael J; Montagnani, Monica

2006-12-01

Spontaneously hypertensive rats (SHRs) exhibit endothelial dysfunction and insulin resistance. Reciprocal relationships between endothelial dysfunction and insulin resistance may contribute to hypertension by causing imbalanced regulation of endothelial-derived vasodilators (e.g., nitric oxide) and vasoconstrictors (e.g., endothelin-1 [ET-1]). Treatment of SHRs with rosiglitazone (insulin sensitizer) and/or enalapril (ACE inhibitor) may simultaneously improve hypertension, insulin resistance, and endothelial dysfunction by rebalancing insulin-stimulated production of vasoactive mediators. When compared with WKY control rats, 12-week-old vehicle-treated SHRs were hypertensive, overweight, and insulin resistant, with elevated fasting levels of insulin and ET-1 and reduced serum adiponectin levels. In mesenteric vascular beds (MVBs) isolated from vehicle-treated SHRs and preconstricted with norepinephrine (NE) ex vivo, vasodilator responses to insulin were significantly impaired, whereas the ability of insulin to oppose vasoconstrictor actions of NE was absent (versus WKY controls). Three-week treatment of SHRs with rosiglitazone and/or enalapril significantly reduced blood pressure, insulin resistance, fasting insulin, and ET-1 levels and increased adiponectin levels to values comparable with those observed in vehicle-treated WKY controls. By restoring phosphatidylinositol 3-kinase-dependent effects, rosiglitazone and/or enalapril therapy of SHRs also significantly improved vasodilator responses to insulin in MVB preconstricted with NE ex vivo. Taken together, our data provide strong support for the existence of reciprocal relationships between endothelial dysfunction and insulin resistance that may be relevant for developing novel therapeutic strategies for the metabolic syndrome.

MINDFULNESS – MAY DIMINISH STRESS AND INCREASE ENERGY

Directory of Open Access Journals (Sweden)

Andronicus TORP

2015-06-01

Full Text Available Mindfulness is increasingly being applied in companies as a means to increase, among others, employee wellbeing and energy, and in the same time to diminish stress. This paper argues that there seems to be scientific evidence showing that certain mindfulness techniques may diminish stress and increase energy, yet it seems that there is a period in the beginning of the mindfulness practice where the techniques have the opposite effects. These findings seem to be contradictory to past findings, which indicated that only two thirds of people practicing mindfulness techniques have positive effects from that practice. It may be that everybody can have positive effects from the practice of the mentioned techniques, just that some need to practice for a longer period before obtaining these positive effects. Further scientific studies seem to be needed in order to clarify the full spectrum of effects and consequences of practicing different mindfulness techniques, and just as important, if these effects are valid for everybody.

Effect of Dietary Docosahexaenoic Acid Supplementation on the Participation of Vasodilator Factors in Aorta from Orchidectomized Rats.

Directory of Open Access Journals (Sweden)

Diva M Villalpando

Full Text Available Benefits of n-3 polyunsaturated fatty acids (PUFAs against cardiovascular diseases have been reported. Vascular tone regulation is largely mediated by endothelial factors whose release is modulated by sex hormones. Since the incidence of cardiovascular pathologies has been correlated with decreased levels of sex hormones, the aim of this study was to analyze whether a diet supplemented with the specific PUFA docosahexaenoic acid (DHA could prevent vascular changes induced by an impaired gonadal function. For this purpose, control and orchidectomized rats were fed with a standard diet supplemented with 5% (w/w sunflower oil or with 3% (w/w sunflower oil plus 2% (w/w DHA. The lipid profile, the blood pressure, the production of prostanoids and nitric oxide (NO, and the redox status of biological samples from control and orchidectomized rats, fed control or DHA-supplemented diet, were analyzed. The vasodilator response and the contribution of NO, prostanoids and hyperpolarizing mechanisms were also studied. The results showed that orchidectomy negatively affected the lipid profile, increased the production of prostanoids and reactive oxygen species (ROS, and decreased NO production and the antioxidant capacity, as well as the participation of hyperpolarizing mechanisms in the vasodilator responses. The DHA-supplemented diet of the orchidectomized rats decreased the release of prostanoids and ROS, while increasing NO production and the antioxidant capacity, and it also improved the lipid profile. Additionally, it restored the participation of hyperpolarizing mechanisms by activating potassium. Since the modifications induced by the DHA-supplemented diet were observed in the orchidectomized, but not in the healthy group, DHA seems to exert cardioprotective effects in physiopathological situations in which vascular dysfunction exists.

Diminished exercise capacity and mitochondrial bc1 complex deficiency in tafazzin-knockdown mice.

Directory of Open Access Journals (Sweden)

Corey ePowers

2013-04-01

Full Text Available The phospholipid, cardiolipin, is essential for maintaining mitochondrial structure and optimal function. Cardiolipin-deficiency in humans, Barth syndrome, is characterized by exercise intolerance, dilated cardiomyopathy, neutropenia and 3-methyl-glutaconic aciduria. The causative gene is the mitochondrial acyl-transferase, tafazzin that is essential for remodeling acyl chains of cardiolipin. We sought to determine metabolic rates in tafazzin-deficient mice during resting and exercise, and investigate the impact of cardiolipin deficiency on mitochondrial respiratory chain activities. Tafazzin knockdown in mice markedly impaired oxygen consumption rates during an exercise, without any significant effect on resting metabolic rates. CL-deficiency resulted in significant reduction of mitochondrial respiratory reserve capacity in neonatal cardiomyocytes that is likely to be caused by diminished activity of complex-III, which requires CL for its assembly and optimal activity. Our results may provide mechanistic insights of Barth syndrome pathogenesis.

Incidental finding of hypertension and diminished femoral pulses ...

African Journals Online (AJOL)

2012-06-08

Jun 8, 2012 ... Case Study: Incidental finding of hypertension and diminished femoral pulses. 168. Vol 55 No 2. S Afr Fam Pract 2013. Introduction. Coarctation of the aorta is ... Surgery of the aorta and its branches. Philadelphia: WB Saunders Company, 2000; p. 3-10. 2. Rao PS. Coarctation of the aorta. Curr Cardiol Rep.

Multi-layered see-through movie in diminished reality

Science.gov (United States)

Uematsu, Yuko; Hashimoto, Takanori; Inoue, Takuya; Shimizu, Naoki; Saito, Hideo

2012-03-01

This paper presents generating a multi-layered see-through movie for an auto-stereoscopic display. This work is based on Diminished Reality (DR), which is one of the research fields of Augmented Reality (AR). In the usual AR, some virtual objects are added on the real world. On the other hand, DR removes some real objects from the real world. Therefore, the background is visualized instead of the real objects (obstacles) to be removed. We use multiple color cameras and one TOF depth camera. The areas of obstacles are defined by using the depth camera based on the distance of obstacles. The background behind the obstacles is recovered by planarprojection of multiple cameras. Then, the recovered background is overlaid onto the removed obstacles. For visualizing it through the auto-stereoscopic display, the scene is divided into multiple layers such as obstacles and background. The pixels corresponding to the obstacles are not visualized or visualized semi-transparently at the center viewpoints. Therefore, we can see that the obstacles are diminished according to the viewpoints.

The relative effectiveness of extinction and counter-conditioning in diminishing children's fear.

Science.gov (United States)

Newall, Carol; Watson, Tiffany; Grant, Kerry-Ann; Richardson, Rick

2017-08-01

Two behavioural strategies for reducing learned fear are extinction and counter-conditioning, and in this study we compared the relative effectiveness of the two procedures at diminishing fear in children. Seventy-three children aged 7-12 years old (M = 9.30, SD = 1.62) were exposed to pictures of two novel animals on a computer screen during the fear acquisition phase. One of these animals was paired with a picture of a scared human face (CS+) while the other was not (CS-). The children were then randomly assigned to one of three conditions: counter-conditioning (animal paired with a happy face), extinction (animal without scared face), or control (no fear reduction procedure). Changes in fear beliefs and behavioural avoidance of the animal were measured. Counter-conditioning was more effective at reducing fear to the CS + than extinction. The findings are discussed in terms of implications for behavioural treatments of childhood anxiety disorders. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Socioeconomic Status and Self-Rated Oral Health; Diminished Return among Hispanic Whites.

Science.gov (United States)

Assari, Shervin

2018-04-24

Background. An extensive body of knowledge has documented weaker health effects of socio-economic status (SES) for Blacks compared to Whites, a phenomenon also known as Blacks’ diminished return. It is, however, unknown whether the same diminished return also holds for other ethnic minorities such as Hispanics or not. Aim. Using a nationally representative sample, the current study aimed to compare Non-Hispanic and Hispanic Whites for the effects of SES on self-rated oral health. Methods. For the current cross-sectional study, we used data from the Collaborative Psychiatric Epidemiology Surveys (CPES), 2001⁻2003. With a nationally representative sampling, CPES included 11,207 adults who were either non-Hispanic Whites ( n = 7587) or Hispanic Whites ( n = 3620. The dependent variable was self-rated oral health, treated as dichotomous measure. Independent variables were education, income, employment, and marital status. Ethnicity was the focal moderator. Age and gender were covariates. Logistic regressions were used for data analysis. Results. Education, income, employment, and marital status were associated with oral health in the pooled sample. Although education, income, employment, and marital status were associated with oral health in non-Hispanic Whites, none of these associations were found for Hispanic Whites. Conclusion. In a similar pattern to Blacks’ diminished return, differential gain of SES indicators exists between Hispanic and non-Hispanic Whites, with a disadvantage for Hispanic Whites. Diminished return of SES should be regarded as a systemically neglected contributing mechanism behind ethnic oral health disparities in the United States. Replication of Blacks’ diminished return for Hispanics suggests that these processes are not specific to ethnic minority groups, and non-White groups gain less because they are not enjoying the privilege and advantage of Whites.

Glucagon-like peptide-1 elicits vasodilation in adipose tissue and skeletal muscle in healthy men

DEFF Research Database (Denmark)

Asmar, Ali; Asmar, Meena; Simonsen, Lene

2017-01-01

In healthy subjects, we recently demonstrated that during acute administration of GLP-1, cardiac output increased significantly, whereas renal blood flow remained constant. We therefore hypothesize that GLP-1 induces vasodilation in other organs, for example, adipose tissue, skeletal muscle, and....../or splanchnic tissues. Nine healthy men were examined twice in random order during a 2-hour infusion of either GLP-1 (1.5 pmol kg(-1) min(-1)) or saline. Cardiac output was continuously estimated noninvasively concomitantly with measurement of intra-arterial blood pressure. Subcutaneous, abdominal adipose...... and heart rate compared with the saline study. Subcutaneous, abdominal ATBF and leg blood flow increased significantly during the GLP-1 infusion compared with saline, whereas splanchnic blood flow response did not differ between the studies. We conclude that in healthy subjects, GLP-1 increases cardiac...

Impact of cancer treatment on risk of infertility and diminished ovarian reserve in women with polycystic ovary syndrome.

Science.gov (United States)

Shandley, Lisa M; Fothergill, Amy; Spencer, Jessica B; Mertens, Ann C; Cottrell, Hanh N; Howards, Penelope P

2018-03-01

To compare markers of fertility and ovarian reserve between cancer survivors and cancer-free women with and without polycystic ovary syndrome (PCOS). Furthering Understanding of Cancer, Health, and Survivorship in Adult (FUCHSIA) Women's Study-a population-based cohort study. Not applicable. Female cancer survivors (n = 1,090) aged 22-45 years, diagnosed between ages 20 and 35 years, and at least 2 years after diagnosis; 369 participated in a clinic visit. Three hundred seventy-four reproductive-aged women without cancer also completed a clinic visit. None. Infertility, time to first pregnancy after cancer diagnosis, and measures of ovarian reserve (antimüllerian hormone [AMH] and antral follicle count [AFC]). Seventy-eight cancer survivors (7.2%) reported a PCOS diagnosis, with 41 receiving gonadotoxic treatment. Survivors with PCOS exposed to gonadotoxic treatment (odds ratio [OR] 2.3, 95% confidence interval [CI] 1.2-4.5) and unexposed (OR 3.4, 95% CI 1.7-6.9) were more likely to report infertility than unexposed survivors without PCOS and were more likely to have fewer children than desired (exposed: OR 2.1, 95% CI 1.0-4.2; unexposed: OR 3.0, 95% CI 1.4-6.8). After adjusting for age, comparison women with PCOS had the highest markers of ovarian reserve (AMH: 2.43 ng/mL, 95% CI 1.22-4.82 ng/mL; AFC: 20.7, 95% CI 15.3-27.8), and cancer survivors without PCOS treated with gonadotoxic agents had the lowest levels (AMH: 0.19 ng/mL, 95% CI 0.14-0.26 ng/mL; AFC: 7.4, 95% CI 6.4-8.5). Despite having higher AMH and AFC on average after cancer treatment, cancer survivors with PCOS were less likely to meet their reproductive goals compared with survivors without PCOS. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

PACAP-38 infusion causes sustained vasodilation of the middle meningeal artery in the rat

DEFF Research Database (Denmark)

Bhatt, Deepak K; Gupta, Saurabh; Olesen, Jes

2014-01-01

BACKGROUND: In healthy human volunteers and in migraineurs, pituitary adenylate cyclase-activating polypeptide-38 (PACAP-38) infusion caused sustained vasodilation of the middle meningeal artery (MMA) and an immediate as well as a delayed headache. All the study subjects experienced facial flushing....... Mast cells (MCs) might have a role in the long-lasting effect of PACAP-38 infusion. We hypothesized that in mast cell-depleted (MCD) rats the vascular responses to PACAP-38 would be lesser than in control rats because of a lack of vasodilatory products released during MC degranulation. METHODS: MCs...... were depleted by chronic treatment with compound 48/80. The effect of 20 minutes' intravenous (i.v.) infusion of calcitonin gene-related peptide (CGRP), PACAP-38, PACAP(6-38) (PAC-1 receptor antagonist) and PACAP-27 on the diameter of the MMA and on mean arterial blood pressure (MABP) in control...

Extracellular adenosine initiates rapid arteriolar vasodilation induced by a single skeletal muscle contraction in hamster cremaster muscle.

Science.gov (United States)

Ross, G A; Mihok, M L; Murrant, C L

2013-05-01

Recent studies suggest that adenosine (ADO) can be produced extracellularly in response to skeletal muscle contraction. We tested the hypothesis that a single muscle contraction produces extracellular ADO rapidly enough and in physiologically relevant concentrations to be able to contribute to the rapid vasodilation that occurs at the onset of muscle contraction. We stimulated four to five skeletal muscle fibres in the anaesthetized hamster cremaster preparation in situ and measured the change in diameter of arterioles at a site of overlap with the stimulated muscle fibres before and after a single contraction (stimulus frequencies: 4, 20 and 60 Hz; 250 ms train duration). Muscle fibres were stimulated in the absence and presence of non-specific ADO membrane receptor antagonists 8-phenyltheophylline (8-PT, 10(-6) M) or xanthine amine congener (XAC, 10(-6) M) or an inhibitor of an extracellular source of ADO, ecto-5'-nucleotidase inhibitor α,β-methylene adenosine 5'-diphosphate (AMPCP, 10(-5) M). We observed that the dilatory event at 4 s following a single contraction was significantly inhibited at all stimulus frequencies by an average of 63.9 ± 2.6% by 8-PT. The 20-s dilatory event that occurred at 20 and 60 Hz was significantly inhibited by 53.6 ± 2.6 and 73.8 ± 2.3% by 8-PT and XAC respectively. Further, both the 4- and 20-s dilatory events were significantly inhibited by AMPCP by 78.6 ± 6.6 and 67.1 ± 1.5%, respectively, at each stimulus frequency tested. Our data show that ADO is produced extracellularly during a single muscle contraction and that it is produced rapidly enough and in physiologically relevant concentrations to contribute to the rapid vasodilation in response to muscle contraction. © 2013 The Authors Acta Physiologica © 2013 Scandinavian Physiological Society.

Ghrelin-related peptides do not modulate vasodilator nitric oxide production or superoxide levels in mouse systemic arteries.

Science.gov (United States)

Ku, Jacqueline M; Sleeman, Mark W; Sobey, Christopher G; Andrews, Zane B; Miller, Alyson A

2016-04-01

The ghrelin gene is expressed in the stomach where it ultimately encodes up to three peptides, namely, acylated ghrelin, des-acylated ghrelin and obestatin, which all have neuroendocrine roles. Recently, the authors' reported that these peptides have important physiological roles in positively regulating vasodilator nitric oxide (NO) production in the cerebral circulation, and may normally suppress superoxide production by the pro-oxidant enzyme, Nox2-NADPH oxidase. To date, the majority of studies using exogenous peptides infer that they may have similar roles in the systemic circulation. Therefore, this study examined whether exogenous and endogenous ghrelin-related peptides modulate NO production and superoxide levels in mouse mesenteric arteries and/or thoracic aorta. Using wire myography, it was found that application of exogenous acylated ghrelin, des-acylated ghrelin or obestatin to mouse thoracic aorta or mesenteric arteries failed to elicit a vasorelaxation response, whereas all three peptides elicited vasorelaxation responses of rat thoracic aorta. Also, none of the peptides modulated mouse aortic superoxide levels as measured by L-012-enhanced chemiluminescence. Next, it was found that NO bioactivity and superoxide levels were unaffected in the thoracic aorta from ghrelin-deficient mice when compared with wild-type mice. Lastly, using novel GHSR-eGFP reporter mice in combination with double-labelled immunofluorescence, no evidence was found for the growth hormone secretagogue receptor (GHSR1a) in the throracic aorta, which is the only functional ghrelin receptor identified to date. Collectively these findings demonstrate that, in contrast to systemic vessels of other species (e.g. rat and human) and mouse cerebral vessels, ghrelin-related peptides do not modulate vasodilator NO production or superoxide levels in mouse systemic arteries. © 2016 John Wiley & Sons Australia, Ltd.

Vision-guided ocular growth in a mutant chicken model with diminished visual acuity.

Science.gov (United States)

Ritchey, Eric R; Zelinka, Christopher; Tang, Junhua; Liu, Jun; Code, Kimberly A; Petersen-Jones, Simon; Fischer, Andy J

2012-09-01

Visual experience is known to guide ocular growth. We tested the hypothesis that vision-guided ocular growth is disrupted in a model system with diminished visual acuity. We examine whether ocular elongation is influenced by form-deprivation (FD) and lens-imposed defocus in the Retinopathy, Globe Enlarged (RGE) chicken. Young RGE chicks have poor visual acuity, without significant retinal pathology, resulting from a mutation in guanine nucleotide-binding protein β3 (GNB3), also known as transducin β3 or Gβ3. The mutation in GNB3 destabilizes the protein and causes a loss of Gβ3 from photoreceptors and ON-bipolar cells (Ritchey et al., 2010). FD increased ocular elongation in RGE eyes in a manner similar to that seen in wild-type (WT) eyes. By comparison, the excessive ocular elongation that results from hyperopic defocus was increased, whereas myopic defocus failed to significantly decrease ocular elongation in RGE eyes. Brief daily periods of unrestricted vision interrupting FD prevented ocular elongation in RGE chicks in a manner similar to that seen in WT chicks. Glucagonergic amacrine cells differentially expressed the immediate early gene Egr1 in response to growth-guiding stimuli in RGE retinas, but the defocus-dependent up-regulation of Egr1 was lesser in RGE retinas compared to that of WT retinas. We conclude that high visual acuity, and the retinal signaling mediated by Gβ3, is not required for emmetropization and the excessive ocular elongation caused by FD and hyperopic defocus. However, the loss of acuity and Gβ3 from RGE retinas causes enhanced responses to hyperopic defocus and diminished responses to myopic defocus. Copyright © 2012 Elsevier Ltd. All rights reserved.

Cold-induced vasodilation comparison between Bangladeshi and Japanese natives.

Science.gov (United States)

Khatun, Aklima; Ashikaga, Sakura; Nagano, Hisaho; Hasib, Md Abdul; Taimura, Akihiro

2016-05-03

The human thermoregulation system responds to changes in environmental temperature, so humans can self-adapt to a wide range of climates. People from tropical and temperate areas have different cold tolerance. This study compared the tolerance of Bangladeshi (tropical) and Japanese (temperate) people to local cold exposure on cold-induced vasodilation (CIVD). Eight Bangladeshi males (now residing in Japan) and 14 Japanese males (residing in Japan) participated in this study. All are sedentary, regular university students. The Bangladeshi subject's duration of stay in Japan was 2.50 ± 2.52 years. The subject's left hand middle finger was immersed in 5 °C water for 20 min to assess their CIVD response (the experiment was conducted in an artificial climate chamber controlled at 25 °C with 50% RH). Compared with the Bangladeshi (BD) group, the Japanese (JP) group displayed some differences. There were significant differences between the BD and JP groups in temperature before immersion (TBI), which were 33.04 ± 1.98 and 34.62 ± 0.94 °C, and time of temperature rise (TTR), which were 5.35 ± 0.82 and 3.72 ± 0.68 min, respectively. There was also a significant difference in the time of sensation rise (TSR) of 8.69 ± 6.49 and 3.26 ± 0.97 min between the BD and JP groups, respectively (P cold exposure than the Bangladeshi group (tropical) evaluated by the CIVD test.

The use of coronary vasodilators in myocardial imaging with 43K

International Nuclear Information System (INIS)

Markov, A.K.; Smith, R.O.; Oglethorpe, N.C.; Lehan, P.H.; Hellems, H.K.

1980-01-01

As an alternative procedure to the exercise stress test used in myocardial scanning, vasoactive drugs were employed to elicit deficits in blood flow to myocardial regions supplied by stenotic arteries. The data were collected from 35 dogs, some of which had partial stenosis on either major branch of the left coronary artery, and others which had Ameroid constrictor implants. The effects of lidoflazine, dipyridamole, and nitroglycerin on coronary hemodynamics and myocardial dispersion of 43 K in animals with partial stenosis were evaluated in ten acute experiments. In the pilot studies, four rapid serial rectilinear control scans from 43 K (750 μCi) were reported; dipyridamole, lidoflazine, or nitroglycerin were then administered intravenously. When the selected drug reached a peak vasodilatative effect, a second equal bolus of 43 K was given and four additional scans recorded. The control scans from dogs with partial stenosis or an Ameroid constrictor showed homogeneous distribution of the myocardial 43 K. When drugs were used, the region supplied by compromised circulation became apparent because of lower counts when compared to the normally perfused ones. Coronary vasodilators, as opposed to postexercise in myocardial imaging, have a lesser effect on cardiac dynamics, peripheral hemodynamics, and also double the 43 K uptake in normally perfused myocardium. (orig.) [de

Bradykinin or acetylcholine as vasodilators to test endothelial venous function in healthy subjects

Directory of Open Access Journals (Sweden)

Eneida R. Rabelo

2008-01-01

Full Text Available INTRODUCTION: The evaluation of endothelial function has been performed in the arterial bed, but recently evaluation within the venous system has also been explored. Endothelial function studies employ different drugs that act as endothelium-dependent vasodilatory response inductors. OBJECTIVES: The aim of this study is to compare the endothelium-dependent venous vasodilator response mediated by either acetylcholine or bradykinin in healthy volunteers. METHODS AND RESULTS: Changes in vein diameter after phenylephrine-induced venoconstriction were measured to compare venodilation induced by acetylcholine or bradykinin (linear variable differential transformer dorsal hand vein technique. We studied 23 healthy volunteers; 31% were male, and the subject had a mean age of 33 ± 8 years and a mean body mass index of 23 ± 2 kg/m². The maximum endothelium-dependent venodilation was similar for both drugs (p = 0.13, as well as the mean responses for each dose of both drugs (r = 0.96. The maximum responses to acetylcholine and bradykinin also had good agreement. CONCLUSION: There were no differences between acetylcholine and bradykinin as venodilators in this endothelial venous function investigation.

Diminishing-cues retrieval practice: A memory-enhancing technique that works when regular testing doesn't.

Science.gov (United States)

Fiechter, Joshua L; Benjamin, Aaron S

2017-08-28

Retrieval practice has been shown to be a highly effective tool for enhancing memory, a fact that has led to major changes to educational practice and technology. However, when initial learning is poor, initial retrieval practice is unlikely to be successful and long-term benefits of retrieval practice are compromised or nonexistent. Here, we investigate the benefit of a scaffolded retrieval technique called diminishing-cues retrieval practice (Finley, Benjamin, Hays, Bjork, & Kornell, Journal of Memory and Language, 64, 289-298, 2011). Under learning conditions that favored a strong testing effect, diminishing cues and standard retrieval practice both enhanced memory performance relative to restudy. Critically, under learning conditions where standard retrieval practice was not helpful, diminishing cues enhanced memory performance substantially. These experiments demonstrate that diminishing-cues retrieval practice can widen the range of conditions under which testing can benefit memory, and so can serve as a model for the broader application of testing-based techniques for enhancing learning.

Anti-Müllerian Hormone as a marker of ovarian reserve in relation to cardio-metabolic health : A narrative review

NARCIS (Netherlands)

De Kat, Annelien C.; Broekmans, Frank J M; Laven, Joop S.; Van Der Schouw, Yvonne T.

2015-01-01

The final hallmark of diminishing ovarian reserve is menopause, a state known to be inextricably linked to the deterioration of female cardiovascular health. The menopausal transition is associated with an increased risk of future cardiovascular morbidity and mortality, irrespective of chronological

Targeted metabolomics reveals reduced levels of polyunsaturated choline plasmalogens and a smaller dimethylarginine/arginine ratio in the follicular fluid of patients with a diminished ovarian reserve.

Science.gov (United States)

de la Barca, J M Chao; Boueilh, T; Simard, G; Boucret, L; Ferré-L'Hotellier, V; Tessier, L; Gadras, C; Bouet, P E; Descamps, P; Procaccio, V; Reynier, P; May-Panloup, P

2017-11-01

Does the metabolomic profile of the follicular fluid (FF) of patients with a diminished ovarian reserve (DOR) differ from that of patients with a normal ovarian reserve (NOR)? The metabolomic signature of the FF reveals a significant decrease in polyunsaturated choline plasmalogens and methyl arginine transferase activity in DOR patients compared to NOR patients. The composition of the FF reflects the exchanges between the oocyte and its microenvironment during its acquisition of gametic competence. Studies of the FF have allowed identification of biomarkers and metabolic pathways involved in various pathologies affecting oocyte quality, but no large metabolomic analysis in the context of ovarian ageing and DOR has been undertaken so far. This was an observational study of the FF retrieved from 57 women undergoing in vitro fertilization at the University Hospital of Angers, France, from November 2015 to September 2016. The women were classified in two groups: one including 28 DOR patients, and the other including 29 NOR patients, serving as controls. Patients were enrolled in the morning of oocyte retrieval after ovarian stimulation. Once the oocytes were isolated for fertilization and culture, the FF was pooled and centrifuged for analysis. A targeted quantitative metabolomic analysis was performed using high-performance liquid chromatography coupled with tandem mass spectrometry, and the Biocrates Absolute IDQ p180 kit. The FF levels of 188 metabolites and several sums and ratios of metabolic significance were assessed by multivariate and univariate analyses. A total of 136 metabolites were accurately quantified and used for calculating 23 sums and ratios. Samples were randomly divided into training and validation sets. The training set, allowed the construction of multivariate statistical models with a projection-supervised method, i.e. orthogonal partial least squares discriminant analysis (OPLS-DA), applied to the full set of metabolites, or the penalized

Ovarian reserve after treatment with alkylating agents during childhood.

Science.gov (United States)

Thomas-Teinturier, Cécile; Allodji, Rodrigue Sétchéou; Svetlova, Ekaterina; Frey, Marie-Alix; Oberlin, Odile; Millischer, Anne-Elodie; Epelboin, Sylvie; Decanter, Christine; Pacquement, Helene; Tabone, Marie-Dominique; Sudour-Bonnange, Helene; Baruchel, André; Lahlou, Najiba; De Vathaire, Florent

2015-06-01

What is the effect of different alkylating agents used without pelvic radiation to treat childhood cancer in girls on the ovarian reserve in survivors? Ovarian reserve seems to be particularly reduced in survivors who received procarbazine (in most cases for Hodgkin lymphoma) or high-dose chemotherapy; procarbazine but not cyclophosphamide dose is associated with diminished ovarian reserve. A few studies have demonstrated diminished ovarian reserve in survivors after various combination therapies, but the individual role of each treatment is difficult to assess. Prospective cross-sectional study, involving 105 survivors and 20 controls. One hundred and five survivors aged 17-40 years and 20 controls investigated on Days 2-5 of a menstrual cycle or Day 7 of an oral contraceptive pill-free interval. ovarian surface area (OS), total number of antral follicles (AFC), serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol and anti-Müllerian hormone (AMH). Survivors had a lower OS than controls: 3.5 versus 4.4 cm(2) per ovary (P = 0.0004), and lower AMH levels: 10.7 versus 22 pmol/l (P = 0.003). Ovarian markers (OS, AMH, AFC) were worse in patients who received high-dose compared with conventional-dose alkylating agents (P = 0.01 for OS, P = 0.002 for AMH, P < 0.0001 for AFC). Hodgkin lymphoma survivors seemed to have a greater reduction in ovarian reserve than survivors of leukaemia (P = 0.04 for AMH, P = 0.01 for AFC), sarcoma (P = 0.04 for AMH, P = 0.04 for AFC) and other lymphomas (P = 0.04 for AFC). A multiple linear regression analysis showed that procarbazine but not cyclophosphamide nor ifosfamide dose was associated with reduced OS (P = 0.0003), AFC (P = 0.0007), AMH (P < 0.0001) and higher FSH levels (P < 0.0001). The small percentage of participating survivors (28%) from the total cohort does not allow conclusion on fertility issues because of possible response bias. The association between procarbazine and HL makes it

An Update on Ovarian Aging and Ovarian Reserve Tests

Directory of Open Access Journals (Sweden)

Migraci Tosun

2016-12-01

Full Text Available Ovaries are the female organs that age more quickly than other tissues such as the uterus, the pituitary gland or pancreas. Different from males, an interesting question is why and how the females lose fertility so rapidly. During the aging process, both the number and quality of the oocytes in the ovaries decrease and reach to a point beyond that no more viable offspring may be produced and the associated cyclic endocrinological activities cease, entering the menopause in females at an average age of 50 years. Females who delayed childbearing with or without their willing until their 30 years or 40 years constitute the largest portion of the total infertility population. Ovarian reserve tests (ORTs provide an indirect estimate of a female�s diminishing ovarian reserve or remaining follicular pool. This article briefly reviews recent progresses in relation to ovarian aging and ORTs.

New diagnostic tests of GH reserve.

Science.gov (United States)

Martul, P; Pineda, J; Pombo, M; Peñalva, A; Bokser, L; Dieguez, C

1993-01-01

Pharmacological tests are essential for the diagnosis of growth hormone (GH) insufficiency. Obesity is a pathological state associated with blunted GH response to all the classical stimuli tested. In the present study, three new pharmacological stimuli for GH reserve were evaluated in three groups of subjects: Normal, GH-insufficient and normal growing obese children. Dexamethasone provokes a clear GH-response in normal children, whereas the response in the other 2 groups of patients is significantly diminished. Galanin-induced GH-secretion is significantly higher in normal than in obese children. GHRP-6 causes a potent GH release in normal children, higher than in GH-insufficiency or obesity. The overlap shown between GH-insufficient patients and normal children reduces the usefulness of the tests. Similar to the classical stimuli, the response to these new tests is also decreased in obesity.

Diminished fronto-limbic functional connectivity in child sexual offenders.

Science.gov (United States)

Kneer, Jonas; Borchardt, Viola; Kärgel, Christian; Sinke, Christopher; Massau, Claudia; Tenbergen, Gilian; Ponseti, Jorge; Walter, Henrik; Beier, Klaus M; Schiffer, Boris; Schiltz, Kolja; Walter, Martin; Kruger, Tillmann H C

2018-02-22

Child sexual abuse and neglect have been related to an increased risk for the development of a wide range of behavioral, psychological, and sexual problems and increased rates of suicidal behavior. Contrary to the large amount of research focusing on the negative mental health consequences of child sexual abuse, very little is known about the characteristics of child sexual offenders and the neuronal underpinnings contributing to child sexual offending. This study investigates differences in resting state functional connectivity (rs-FC) between non-pedophilic child sexual offenders (N = 20; CSO-P) and matched healthy controls (N = 20; HC) using a seed-based approach. The focus of this investigation of rs-FC in CSO-P was put on prefrontal and limbic regions highly relevant for emotional and behavioral processing. Results revealed a significant reduction of rs-FC between the right centromedial amygdala and the left dorsolateral prefrontal cortex in child sexual offenders compared to controls. Given that, in the healthy brain, there is a strong top-down inhibitory control of prefrontal over limbic structures, these results suggest that diminished rs-FC between the amygdala and the dorsolateral prefrontal cortex and may foster sexual deviance and sexual offending. A profound understanding of these concepts should contribute to a better understanding of the occurrence of child sexual offending, as well as further development of more differentiated and effective interventions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Impaired Retinal Vasodilator Responses in Prediabetes and Type 2 Diabetes

Science.gov (United States)

Lott, Mary E.J.; Slocomb, Julia E.; Shivkumar, Vikram; Smith, Bruce; Quillen, David; Gabbay, Robert A.; Gardner, Thomas W.; Bettermann, Kerstin

2013-01-01

Purpose In diabetes, endothelial dysfunction and subsequent structural damage to blood vessels can lead to heart attacks, retinopathy and strokes. However, it is unclear whether prediabetic subjects exhibit microvascular dysfunction indicating early stages of arteriosclerosis and vascular risk. The purpose of this study was to examine whether retinal reactivity may be impaired early in the hyperglycemic continuum and may be associated with markers of inflammation. Methods Individuals with prediabetes (n = 22), type 2 diabetes (n = 25) and healthy age and body composition matched controls (n = 19) were studied. We used the Dynamic Vessel Analyzer to assess retinal vasoreactivity (percent change in vessel diameter) during a flickering light stimulation. Fasting highly sensitive c-reactive protein (hs-CRP), a marker of inflammation, was measured in blood plasma. Results Prediabetic and diabetic individuals had attenuated peak vasodilator and relative amplitude changes in retinal vein diameters to the flickering light stimulus compared to healthy controls (peak dilation: prediabetic subjects 3.3 ± 1.8 %, diabetic subjects 3.3 ± 2.1% controls 5.6 ± 2.6%, p = .001; relative amplitude: prediabetic subjects 4.3 ± 2.2%, diabetic subjects 5.0 ± 2.6% and control subjects 7.2 ± 3.2%, p = .003). Similar findings were observed in retinal arteries. Levels of hs-CRP were not associated with either retinal vessel response parameters. Conclusion Retinal reactivity was impaired in prediabetic and type 2 diabetic individuals in parallel with reduced insulin sensitivity but not associated with levels of hs-CRP. Retinal vasoreactivity measurements may be a sensitive tool to assess early vascular risk. PMID:23742315

The roles of KCa, KATP, and KV channels in regulating cutaneous vasodilation and sweating during exercise in the heat.

Science.gov (United States)

Louie, Jeffrey C; Fujii, Naoto; Meade, Robert D; McNeely, Brendan D; Kenny, Glen P

2017-05-01

We recently showed the varying roles of Ca 2+ -activated (K Ca ), ATP-sensitive (K ATP ), and voltage-gated (K V ) K + channels in regulating cholinergic cutaneous vasodilation and sweating in normothermic conditions. However, it is unclear whether the respective contributions of these K + channels remain intact during dynamic exercise in the heat. Eleven young (23 ± 4 yr) men completed a 30-min exercise bout at a fixed rate of metabolic heat production (400 W) followed by a 40-min recovery period in the heat (35°C, 20% relative humidity). Cutaneous vascular conductance (CVC) and local sweat rate were assessed at four forearm skin sites perfused via intradermal microdialysis with: 1 ) lactated Ringer solution (control); 2 ) 50 mM tetraethylammonium (nonspecific K Ca channel blocker); 3 ) 5 mM glybenclamide (selective K ATP channel blocker); or 4 ) 10 mM 4-aminopyridine (nonspecific K V channel blocker). Responses were compared at baseline and at 10-min intervals during and following exercise. K Ca channel inhibition resulted in greater CVC versus control at end exercise ( P = 0.04) and 10 and 20 min into recovery (both P exercise (all P ≤ 0.04), and 10 min into recovery ( P = 0.02). No differences in CVC were observed with K V channel inhibition during baseline ( P = 0.15), exercise (all P ≥ 0.06), or recovery (all P ≥ 0.14). With the exception of K V channel inhibition augmenting sweating during baseline ( P = 0.04), responses were similar to control with all K + channel blockers during each time period (all P ≥ 0.07). We demonstrated that K Ca and K ATP channels contribute to the regulation of cutaneous vasodilation during rest and/or exercise and recovery in the heat. Copyright © 2017 the American Physiological Society.

The feasible study of vasodilators in portal vein targeting infusion for treating portal hypertension

International Nuclear Information System (INIS)

Wu Hanping; Liang Huiming; Zheng Chuansheng; Feng Gansheng

2002-01-01

Objective: To find out the ideal portal vein tar getting injection routes for portal hypertension treatment. Methods: 28 cirrhotic rat models with portal hypertension induced by CCl 4 were divided into 4 groups: inferior caval vein injection group, portal vein injection group, hepatic artery injection group, spleen injection group. The changes in portal vein pressure (PVP), inferior caval vein pressure (ICVP), mean artery pressure (MAP) and heart rate (HR) were monitored before and after prazosin injection. Results: After intra-portal, intra-hepatic arterial or spleen injection of prazosin, larger decrease in PVP and lesser effects on MAP than intravenous injection had been induced. The effect on HR showed no difference among these four groups. Conclusions: Hepatic artery and spleen prazosin administration have the same advantages on treatment of portal hypertension as those of intra-portal infusion, that is the greater decrease on portal vein pressure, the lesser effects on systemic hemodynamics. Vasodilation drugs for hepatic artery infusion through percutaneous port catheter system by hepatic artery implantation would be an ideal method for portal hypertension treatment

Diminished facial emotion expression and associated clinical characteristics in Anorexia Nervosa.

Science.gov (United States)

Lang, Katie; Larsson, Emma E C; Mavromara, Liza; Simic, Mima; Treasure, Janet; Tchanturia, Kate

2016-02-28

This study aimed to investigate emotion expression in a large group of children, adolescents and adults with Anorexia Nervosa (AN), and investigate the associated clinical correlates. One hundred and forty-one participants (AN=66, HC= 75) were recruited and positive and negative film clips were used to elicit emotion expressions. The Facial Activation Coding system (FACES) was used to code emotion expression. Subjective ratings of emotion were collected. Individuals with AN displayed less positive emotions during the positive film clip compared to healthy controls (HC). There was no significant difference between the groups on the Positive and Negative Affect Scale (PANAS). The AN group displayed emotional incongruence (reporting a different emotion to what would be expected given the stimuli, with limited facial affect to signal the emotion experienced), whereby they reported feeling significantly higher rates of negative emotion during the positive clip. There were no differences in emotion expression between the groups during the negative film clip. Despite this individuals with AN reported feeling significantly higher levels of negative emotions during the negative clip. Diminished positive emotion expression was associated with more severe clinical symptoms, which could suggest that these individuals represent a group with serious social difficulties, which may require specific attention in treatment. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Popliteal artery thrombosis in a patient with Cogan syndrome: Treatment with thrombolysis and percutaneous transluminal angioplasty

International Nuclear Information System (INIS)

Bastug, Demir E.; Dominic, Anthony; Ortiz, Orlando; DiBartolomeo, Anthony G.; Kotzan, Jeffrey M.; Abraham, F. Matthew

1997-01-01

A 31-year-old woman with Cogan syndrome (a rare form of systemic vasculitis) was evaluated for a cold, painful left foot with diminished pulses. Arteriography demonstrated thrombosis of the left popliteal artery with evidence of vasculitis. Thrombolytic therapy was begun with initial success but eventual rethrombosis. After reinitiating thrombolytic therapy combined with intraarterial vasodilator therapy, successful angioplasty was performed with sustained results, at 6-month follow-up

Arginase up-regulation and eNOS uncoupling contribute to impaired endothelium-dependent vasodilation in a rat model of intrauterine growth restriction.

Science.gov (United States)

Grandvuillemin, Isabelle; Buffat, Christophe; Boubred, Farid; Lamy, Edouard; Fromonot, Julien; Charpiot, Philippe; Simoncini, Stephanie; Sabatier, Florence; Dignat-George, Françoise; Peyter, Anne-Christine; Simeoni, Umberto; Yzydorczyk, Catherine

2018-05-09

Individuals born after intrauterine growth restriction (IUGR) are at increased risk of developing cardiovascular diseases in adulthood, notably hypertension (HTN). Alterations in the vascular system, particularly impaired endothelium-dependent vasodilation, may play an important role in long-term effects of IUGR. Whether such vascular dysfunction precedes HTN has not been fully established in individuals born after IUGR. Moreover, the intimate mechanisms of altered endothelium-dependent vasodilation remain incompletely elucidated. We therefore investigated, using a rat model of IUGR, whether impaired endothelium-dependent relaxation precedes the development of HTN and whether key components of the L-Arginine-nitric oxide (NO) pathway are involved in its pathogenesis. Pregnant rats were fed with a control (CTRL, 23% casein) or low-protein diet (LP, 9% casein) to induce IUGR. Systolic blood pressure (SBP) was measured by tail-cuff plethysmography in 5- and 8-week-old male offspring. Aortic rings were isolated to investigate relaxation to acetylcholine, NO production, eNOS protein content, arginase activity, and superoxide anion production. SBP was not different at 5 weeks, but significantly increased in 8-week-old LP vs. CRTL offspring. In 5-week-old LP vs. CRTL males, endothelium-dependent vasorelaxation was significantly impaired, but restored by pre-incubation with L-Arginine or the arginase inhibitor BEC; NO production was significantly reduced, but restored by L-Arginine pretreatment; total eNOS protein, dimer/monomer ratio, and arginase activity were significantly increased; superoxide anion production was significantly enhanced, but normalized by pretreatment with the NOS inhibitor L-NNA. In this model, IUGR leads to early-impaired endothelium-dependent vasorelaxation, resulting from arginase up-regulation and eNOS uncoupling, which precedes the development of HTN.

Effect of nipradilol, a beta-adrenergic blocker with vasodilating activity, on oxotremorine-induced tremor in mice.

Science.gov (United States)

Iwata, S; Nomoto, M; Fukuda, T

1996-10-01

The effect of nipradilol, a nonselective beta-adrenergic receptor blocker with nitroglycerin-like vasodilating activity, on oxotremorine-induced tremor was studied in mice. General tremor in mice was elicited by 0.5 mg/kg oxotremorine. The tremor was quantified using a capacitance transducer, then analyzed by a signal processor. The strength of the tremor was expressed in "points". The point values of the tremor (mean +/- SE) in control mice for 5 mg/kg (+/-)-propranolol, 2.5 mg/kg arotinolol, 0.5 mg/kg nipradilol, 1.0 mg/kg nipradilol and 2.5 mg/kg nipradilol were 87 +/- 16, 42 +/- 6, 38 +/- 6, 99 +/- 28, 28 +/- 6 and 31 +/- 7, respectively. The strength of the tremor was reduced by all beta-blockers. Although 1.0 mg/kg nipradilol significantly reduced the tremor, further inhibition of the tremor was not obtained with dosages up to 2.5 mg/kg of the drug. In conclusion, nipradilol was effective for suppressing oxotremorine-induced tremor, as were other beta-blockers.

Application of numerical method in calculating the internal rate of return of joint venture investment using diminishing musyarakah model

Science.gov (United States)

Ruslan, Siti Zaharah Mohd; Jaffar, Maheran Mohd

2017-05-01

Islamic banking in Malaysia offers variety of products based on Islamic principles. One of the concepts is a diminishing musyarakah. The concept of diminishing musyarakah helps Muslims to avoid transaction which are based on riba. The diminishing musyarakah can be defined as an agreement between capital provider and entrepreneurs that enable entrepreneurs to buy equity in instalments where profits and losses are shared based on agreed ratio. The objective of this paper is to determine the internal rate of return (IRR) for a diminishing musyarakah model by applying a numerical method. There are several numerical methods in calculating the IRR such as by using an interpolation method and a trial and error method by using Microsoft Office Excel. In this paper we use a bisection method and secant method as an alternative way in calculating the IRR. It was found that the diminishing musyarakah model can be adapted in managing the performance of joint venture investments. Therefore, this paper will encourage more companies to use the concept of joint venture in managing their investments performance.

Safety and Efficacy of Intracoronary Vasodilators in the Treatment of No-Reflow after Primary Percutaneous Intervention in Patients with Acute ST-Elevation Myocardial Infarction: A Literature Review

Directory of Open Access Journals (Sweden)

Mostafa Dastani

2016-04-01

Full Text Available Introduction: The investigation of no-reflow phenomenon after Percutaneous Coronary Intervention (PCI in patients with acute ST-segment Elevation Myocardial Infarction (STEMI has therapeutic implications. Several vasodilators were administered through intracoronary injection to treat this phenomenon. We aimed to elucidate the risk factors, predictors, and long-term effects of no-reflow phenomenon, and to compare the effects of various vasodilators on re-opening the obstructed vessels. Materials and Methods: All the reviewed articles were retrieved from MEDLINE and Science Direct (up to October 2014. All no-reflow cases were determined through Thrombolysis in Myocardial Infarction grading (TIMI system. Results: Four articles were included, two of which mainly focused on risk factors, predictors, and long-term prognosis of no-reflow phenomenon, and its association with patient mortality and morbidity. The other two articles evaluated therapeutic interventions and compared their efficacy in treating no-reflow. Conclusion: Development of no-reflow in patients with STEMI after primary PCI is associated with low myocardial salvage by primary PCI, large scintigraphic infarct size, deteriorated left ventricle ejection fraction at six months, and increased risk of first-year mortality. During primary PCI, intracoronary infusion of diltiazem and verapamil can reverse no-reflow more effectively than nitroglycerin.

Data on a single oral dose of camu camu (Myrciaria dubia pericarp extract on flow-mediated vasodilation and blood pressure in young adult humans

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Tadayoshi Miyashita

2018-02-01

Full Text Available This data article describes the flow-mediated vasodilation (FMD responses, represented by changes in arterial diameter, and blood pressure changes in young adults after a single oral dose of camu camu (Myrciaria dubia pericarp extract or placebo (cross-over design. Ten healthy men and 10 healthy women participated in this study. Ultrasonic diagnostic equipment was used to monitor arterial diameter changes, indicative of FMD, for 110 s after the administration of the camu camu extract or placebo. In addition, the systolic and diastolic blood pressure values were recorded.

Data on a single oral dose of camu camu (Myrciaria dubia) pericarp extract on flow-mediated vasodilation and blood pressure in young adult humans.

Science.gov (United States)

Miyashita, Tadayoshi; Koizumi, Ryosuke; Myoda, Takao; Sagane, Yoshimasa; Niwa, Koichi; Watanabe, Toshihiro; Minami, Kazuhiro

2018-02-01

This data article describes the flow-mediated vasodilation (FMD) responses, represented by changes in arterial diameter, and blood pressure changes in young adults after a single oral dose of camu camu ( Myrciaria dubia ) pericarp extract or placebo (cross-over design). Ten healthy men and 10 healthy women participated in this study. Ultrasonic diagnostic equipment was used to monitor arterial diameter changes, indicative of FMD, for 110 s after the administration of the camu camu extract or placebo. In addition, the systolic and diastolic blood pressure values were recorded.

Diminished creatinine clearance in anorexia nervosa: reversal with weight gain.

OpenAIRE

Boag, F; Weerakoon, J; Ginsburg, J; Havard, C W; Dandona, P

1985-01-01

To assess whether patients with anorexia nervosa have abnormalities in creatinine clearance, we measured plasma creatinine concentration, urinary creatinine excretion, and creatinine clearance in 10 patients with anorexia nervosa before and during treatment. Urinary creatinine excretion and creatinine clearance were diminished in all patients. Nine patients had significant decreases in their plasma creatinine and creatinine clearance was increased even when corrected for body weight and body ...

Liposomal nanoparticles encapsulating iloprost exhibit enhanced vasodilation in pulmonary arteries

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Jain PP

2014-07-01

Full Text Available Pritesh P Jain,1 Regina Leber,1,2 Chandran Nagaraj,1 Gerd Leitinger,3 Bernhard Lehofer,4 Horst Olschewski,1,5 Andrea Olschewski,1,6 Ruth Prassl,1,4 Leigh M Marsh11Ludwig Boltzmann Institute for Lung Vascular Research, 2Biophysics Division, Institute of Molecular Biosciences, University of Graz, 3Research Unit Electron Microscopic Techniques, Institute of Cell Biology, Histology, and Embryology, 4Institute of Biophysics, 5Division of Pulmonology, Department of Internal Medicine, 6Department of Anesthesiology and Intensive Care Medicine, Medical University of Graz, Graz, AustriaAbstract: Prostacyclin analogues are standard therapeutic options for vasoconstrictive diseases, including pulmonary hypertension and Raynaud’s phenomenon. Although effective, these treatment strategies are expensive and have several side effects. To improve drug efficiency, we tested liposomal nanoparticles as carrier systems. In this study, we synthesized liposomal nanoparticles tailored for the prostacyclin analogue iloprost and evaluated their pharmacologic efficacy on mouse intrapulmonary arteries, using a wire myograph. The use of cationic lipids, stearylamine, or 1,2-di-(9Z-octadecenoyl-3-trimethylammonium-propane (DOTAP in liposomes promoted iloprost encapsulation to at least 50%. The addition of cholesterol modestly reduced iloprost encapsulation. The liposomal nanoparticle formulations were tested for toxicity and pharmacologic efficacy in vivo and ex vivo, respectively. The liposomes did not affect the viability of human pulmonary artery smooth muscle cells. Compared with an equivalent concentration of free iloprost, four out of the six polymer-coated liposomal formulations exhibited significantly enhanced vasodilation of mouse pulmonary arteries. Iloprost that was encapsulated in liposomes containing the polymer polyethylene glycol exhibited concentration-dependent relaxation of arteries. Strikingly, half the concentration of iloprost in liposomes elicited

Direct Instruction and Music Literacy: One Approach to Augmenting the Diminishing?

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Lowe, Geoffrey; Belcher, Steven

2012-01-01

One of the many challenges facing music educators is diminishing class time in lower secondary school in the face of the increasingly crowded curriculum and the advent of arts "taster" courses. However, music educators are still expected to be able to produce musically literate students capable of completing high level music courses in…

Effect of subchronic exposure to mainstream cigarette smoke on endothelium-dependent vasodilation in rat arteries

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Helena Lenasi

2005-07-01

Full Text Available Background: Cigarette smoking is reported to impair endothelium-dependent vasodilation. The aim of the present study was to assess the effect of 30-day exposure to mainstream cigarette smoke on vascular reactivity of rat abdominal aorta, carotid, renal and mesenteric artery. Separately, the NO-mediated and the EDHF-mediated, endothelium-dependent vascular relaxations were determined.Methods: Two groups of »Whistar Kyoto« rats were exposed to mainstream cigarette smoke (2 hours/day, 5 days/week for 30 days and to fresh conditioned air, respectively. Rats were sacrificed on the second day after the last exposition to cigarette smoke. Vascular reactivity studies were performed on isolated, endothelium-intact, phenylephrine-preconstricted rat artery rings. Cumulative concentration-relaxation curves to acetylcholine (ACh were obtained in the absence and presence of the endothelial NO synthase (eNOS inhibitor N ω nitro L-arginine (L-NA and the cyclo-oxygenase (COX inhibitor diclofenac, respectively. After washing period of 1 hour, vessels were exposed either to the intracellular superoxide scavenger tiron, to the cytochrome P450 (CYP inhibitor miconazole or the Na-K-ATPase inhibitor ouabain before being preconstricted with phenylephrine and determining the concentration-response curve to ACh.Results: ACh induced concentration-dependent relaxations. In none of the vessels investigated did we observe a significant difference in the relaxations obtained in arteries from control rats and rats exposed to cigarettee smoke. Although smoking is known to cause an increase in oxidative stress, treatment of the vessels with tiron did not affect the NOmediated relaxations. To evaluate the contribution of EDHF to endothelium-dependent vasodilation rings were preincubated with L-NA. The EDHF-mediated relaxations were significantly attenuated compared to the NO-mediated relaxations in renal and mesenteric artery and almost completely abolished in aorta and

Brain natriuretic peptide is a potent vasodilator in aged human microcirculation and shows a blunted response in heart failure patients

DEFF Research Database (Denmark)

Edvinsson, Marie-Louise; Uddman, Erik; Edvinsson, Lars

2014-01-01

in the forearm was measured by laser Doppler Flowmetry. Local heating (+44°C, 10 min) was used to evoke a maximum local dilator response. RESULTS: Non-invasive iontophoretic administration of either BNP or acetylcholine (ACh), a known endothelium-dependent dilator, elicited an increase in local flow. The nitric......, the vasodilator responses to ACh and to local heating were only somewhat attenuated in CHF patients. Thus, dilator capacity and nitric oxide signalling were not affected to the same extent as BNP-mediated dilation, indicating a specific downregulation of the latter response. CONCLUSIONS: The findings show...... for the first time that microvascular responses to BNP are markedly reduced in CHF patients. This is consistent with the hypothesis of BNP receptor function is downregulated in CHF....

Marine Reserve Targets to Sustain and Rebuild Unregulated Fisheries.

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Nils C Krueck

2017-01-01

Full Text Available Overfishing threatens the sustainability of coastal marine biodiversity, especially in tropical developing countries. To counter this problem, about 200 governments worldwide have committed to protecting 10%-20% of national coastal marine areas. However, associated impacts on fisheries productivity are unclear and could weaken the food security of hundreds of millions of people who depend on diverse and largely unregulated fishing activities. Here, we present a systematic theoretic analysis of the ability of reserves to rebuild fisheries under such complex conditions, and we identify maximum reserve coverages for biodiversity conservation that do not impair long-term fisheries productivity. Our analysis assumes that fishers have no viable alternative to fishing, such that total fishing effort remains constant (at best. We find that realistic reserve networks, which protect 10%-30% of fished habitats in 1-20 km wide reserves, should benefit the long-term productivity of almost any complex fishery. We discover a "rule of thumb" to safeguard against the long-term catch depletion of particular species: individual reserves should export 30% or more of locally produced larvae to adjacent fishing grounds. Specifically on coral reefs, where fishers tend to overexploit species whose dispersal distances as larvae exceed the home ranges of adults, decisions on the size of reserves needed to meet the 30% larval export rule are unlikely to compromise the protection of resident adults. Even achieving the modest Aichi Target 11 of 10% "effective protection" can then help rebuild depleted catch. However, strictly protecting 20%-30% of fished habitats is unlikely to diminish catch even if overfishing is not yet a problem while providing greater potential for biodiversity conservation and fishery rebuilding if overfishing is substantial. These findings are important because they suggest that doubling or tripling the only globally enforced marine reserve target

Punishment diminishes the benefits of network reciprocity in social dilemma experiments.

Science.gov (United States)

Li, Xuelong; Jusup, Marko; Wang, Zhen; Li, Huijia; Shi, Lei; Podobnik, Boris; Stanley, H Eugene; Havlin, Shlomo; Boccaletti, Stefano

2018-01-02

Network reciprocity has been widely advertised in theoretical studies as one of the basic cooperation-promoting mechanisms, but experimental evidence favoring this type of reciprocity was published only recently. When organized in an unchanging network of social contacts, human subjects cooperate provided the following strict condition is satisfied: The benefit of cooperation must outweigh the total cost of cooperating with all neighbors. In an attempt to relax this condition, we perform social dilemma experiments wherein network reciprocity is aided with another theoretically hypothesized cooperation-promoting mechanism-costly punishment. The results reveal how networks promote and stabilize cooperation. This stabilizing effect is stronger in a smaller-size neighborhood, as expected from theory and experiments. Contrary to expectations, punishment diminishes the benefits of network reciprocity by lowering assortment, payoff per round, and award for cooperative behavior. This diminishing effect is stronger in a larger-size neighborhood. An immediate implication is that the psychological effects of enduring punishment override the rational response anticipated in quantitative models of cooperation in networks. Copyright © 2017 the Author(s). Published by PNAS.

Confronting diminished epistemic privilege and epistemic injustice in pregnancy by challenging a "panoptics of the womb".

Science.gov (United States)

Freeman, Lauren

2015-02-01

This paper demonstrates how the problematic kinds of epistemic power that physicians have can diminish the epistemic privilege that pregnant women have over their bodies and can put them in a state of epistemic powerlessness. This result, I argue, constitutes an epistemic injustice for many pregnant women. A reconsideration of how we understand and care for pregnant women and of the physician-patient relationship can provide us with a valuable context and starting point for helping to alleviate the knowledge/power problems that are symptomatic of the current system and structure of medicine. I suggest that we can begin to confront this kind of injustice if medicine adopts a more phenomenological understanding of bodies and if physicians and patients--in this case, pregnant women--become what I call "epistemic peers." © The Author 2014. Published by Oxford University Press, on behalf of the Journal of Medicine and Philosophy Inc. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Dietary restriction but not angiotensin II type 1 receptor blockade improves DNA damage-related vasodilator dysfunction in rapidly aging Ercc1Δ/- mice.

Science.gov (United States)

Wu, Haiyan; van Thiel, Bibi S; Bautista-Niño, Paula K; Reiling, Erwin; Durik, Matej; Leijten, Frank P J; Ridwan, Yanto; Brandt, Renata M C; van Steeg, Harry; Dollé, Martijn E T; Vermeij, Wilbert P; Hoeijmakers, Jan H J; Essers, Jeroen; van der Pluijm, Ingrid; Danser, A H Jan; Roks, Anton J M

2017-08-01

DNA damage is an important contributor to endothelial dysfunction and age-related vascular disease. Recently, we demonstrated in a DNA repair-deficient, prematurely aging mouse model ( Ercc1 Δ/- mice) that dietary restriction (DR) strongly increases life- and health span, including ameliorating endothelial dysfunction, by preserving genomic integrity. In this mouse mutant displaying prominent accelerated, age-dependent endothelial dysfunction we investigated the signaling pathways involved in improved endothelium-mediated vasodilation by DR, and explore the potential role of the renin-angiotensin system (RAS). Ercc1 Δ/- mice showed increased blood pressure and decreased aortic relaxations to acetylcholine (ACh) in organ bath experiments. Nitric oxide (NO) signaling and phospho-Ser 1177 -eNOS were compromised in Ercc1 Δ / - DR improved relaxations by increasing prostaglandin-mediated responses. Increase of cyclo-oxygenase 2 and decrease of phosphodiesterase 4B were identified as potential mechanisms. DR also prevented loss of NO signaling in vascular smooth muscle cells and normalized angiotensin II (Ang II) vasoconstrictions, which were increased in Ercc1 Δ/- mice. Ercc1 Δ/ - mutants showed a loss of Ang II type 2 receptor-mediated counter-regulation of Ang II type 1 receptor-induced vasoconstrictions. Chronic losartan treatment effectively decreased blood pressure, but did not improve endothelium-dependent relaxations. This result might relate to the aging-associated loss of treatment efficacy of RAS blockade with respect to endothelial function improvement. In summary, DR effectively prevents endothelium-dependent vasodilator dysfunction by augmenting prostaglandin-mediated responses, whereas chronic Ang II type 1 receptor blockade is ineffective. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Continuing versus discontinuing antiplatelet drugs, vasodilators, and/or cerebral ameliorators on perioperative total blood loss in total knee arthroplasty without pneumatic tourniquet

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Sachiyuki Tsukada, MD

2018-03-01

Full Text Available Background: Although studies have supported the utility of perioperative continuation of antiplatelet drugs, vasodilators, and cerebral ameliorators in most procedures, no study compared total volume of blood loss after total knee arthroplasty (TKA in patients continuing and discontinuing these drugs. Methods: We retrospectively reviewed 266 consecutive patients undergoing TKA, and included 67 patients (25.2% taking antiplatelet drugs, vasodilators, or cerebral ameliorators in this study. All TKAs were performed without a pneumatic tourniquet. The primary outcome was perioperative total blood loss calculated from blood volume and change in hemoglobin. As subgroup analysis, we compared perioperative total blood loss in patients taking antiplatelet drugs. Results: There was no significant difference between the continuing group (n = 38 and discontinuing group (n = 29 in terms of the perioperative total blood loss (1025 ± 364 vs 1151 ± 327 mL, respectively; mean difference 126 mL; 95% confidence interval −45 to 298 mL; P = .15. No major bleeding or thrombotic events occurred in either group until postoperative 3-month follow-up. In patients taking antiplatelet drugs (n = 51, no significant difference was observed in the total blood loss between the continuing group (n = 30 and discontinuing group (n = 21 (1056 ± 287 vs 1151 ± 305 mL, respectively; mean difference 95 mL; 95% confidence interval −75 to 264 mL; P = .27. Conclusions: No significant differences in terms of perioperative total blood loss were observed between patients continuing and discontinuing study drugs. Continuing these drugs may be preferable in the perioperative period of TKA. Keywords: Knee, Primary arthroplasty, Bleeding events, Thrombotic events, Noncardiac surgery

[Physical activity diminishes aging-related decline of physical and cognitive performance].

Science.gov (United States)

Apor, Péter; Babai, László

2014-05-25

Aging-related decline of muscle force, walking speed, locomotor coordination, aerobic capacity and endurance exert prognostic impact on life expectancy. Proper use of training may diminish the aging process and it may improve the quality of life of elderly persons. This paper provides a brief summary on the impact of training on aging-related decline of physical and cognitive functions.

Nonsuicidal self-injury and diminished pain perception: the role of emotion dysregulation

NARCIS (Netherlands)

Franklin, J.C.; Aaron, R.V.; Arthur, M.S.; Shorkey, S.P.; Prinstein, M.J.

2012-01-01

Nonsuicidal self-injury (NSSI) is the deliberate destruction of one's own body tissue in the absence of suicidal intent (e.g., cutting or burning the skin). Previous studies have found that people with a history of NSSI display diminished pain perception. However, it remains unclear why this effect

Relaxing Responses to Hydrogen Peroxide and Nitric Oxide in Human Pericardial Resistance Arteries Stimulated with Endothelin-1

DEFF Research Database (Denmark)

Leurgans, Thomas M; Bloksgaard, Maria; Irmukhamedov, Akhmadjon

2018-01-01

In human pericardial resistance arteries, effects of the endothelium-dependent vasodilator bradykinin are mediated by NO during contraction induced by K(+) or the TxA2 analogue U46619 and by H2 O2 during contraction by endothelin-1 (ET-1), respectively. We tested the hypotheses that ET-1 reduces...... also acts as an endothelium-dependent vasodilator. This article is protected by copyright. All rights reserved....

Interaction of selected vasodilating beta-blockers with adrenergic receptors in human cardiovascular tissues

International Nuclear Information System (INIS)

Monopoli, A.; Forlani, A.; Bevilacqua, M.; Vago, T.; Norbiato, G.; Bertora, P.; Biglioli, P.; Alamanni, F.; Ongini, E.

1989-01-01

beta- And alpha 1-adrenoceptor antagonist properties of bufuralol, carvedilol, celiprolol, dilevalol, labetalol, and pindolol were investigated in human myocardium and mammary artery using binding techniques and functional studies. In myocardial membranes, beta-adrenoceptor antagonists showed monophasic competition isotherms for [125I]pindolol binding with high affinity (Ki from 1-100 nM), except for celiprolol which displayed a biphasic competition isotherm (pKi = 6.4 +/- 0.06 for beta 1- and 4.8 +/- 0.07 for beta 2-adrenoceptors). Drug interactions with alpha 1-adrenoceptors were evaluated in human mammary artery by [3H]prazosin binding and by measuring contractile responses to norepinephrine (NE). Labetalol and carvedilol showed a moderate affinity for alpha 1-adrenoceptors (pKi = 6.2 +/- 0.01 and 6.1 +/- 0.06, respectively), and inhibited NE-induced contractions (pA2 = 6.93 +/- 0.23 and 8.64 +/- 0.24, respectively). Dilevalol, bufuralol, and pindolol displayed weak effect both in binding (Ki in micromolar range) and functional experiments (pA2 = 5.98, 5.54, and 6.23, respectively). Celiprolol did not show antagonist properties up to 100 microM in functional studies, but displayed a slight affinity for alpha 1-adrenoceptors in binding studies. The data indicate that the vasodilating activity of these beta-adrenoceptor antagonists is caused in some instances by an alpha 1-adrenoceptor antagonism (labetalol, carvedilol), whereas for the others alternative mechanisms should be considered

Temporal changes in giant panda habitat connectivity across boundaries of Wolong Nature Reserve, China.

Science.gov (United States)

Viña, Andrés; Bearer, Scott; Chen, Xiaodong; He, Guangming; Linderman, Marc; An, Li; Zhang, Hemin; Ouyang, Zhiyun; Liu, Jianguo

2007-06-01

Global biodiversity loss is largely driven by human activities such as the conversion of natural to human-dominated landscapes. A popular approach to mitigating land cover change is the designation of protected areas (e.g., nature reserves). Nature reserves are traditionally perceived as strongholds of biodiversity conservation. However, many reserves are affected by land cover changes not only within their boundaries, but also in their surrounding areas. This study analyzed the changes in habitat for the giant panda (Ailuropoda melanoleuca) inside Wolong Nature Reserve, Sichuan, China, and in a 3-km buffer area outside its boundaries, through a time series of classified satellite imagery and field observations. Habitat connectivity between the inside and the outside of the reserve diminished between 1965 and 2001 because panda habitat was steadily lost both inside and outside the reserve. However, habitat connectivity slightly increased between 1997 and 2001 due to the stabilization of some panda habitat inside and outside the reserve. This stabilization most likely occurred as a response to changes in socioeconomic activities (e.g., shifts from agricultural to nonagricultural economies). Recently implemented government policies could further mitigate the impacts of land cover change on panda habitat. The results suggest that Wolong Nature Reserve, and perhaps other nature reserves in other parts of the world, cannot be managed as an isolated entity because habitat connectivity declines with land cover changes outside the reserve even if the area inside the reserve is well protected. The findings and approaches presented in this paper may also have important implications for the management of other nature reserves across the world.

Smoking Through a Topography Device Diminishes Some of the Acute Rewarding Effects of Smoking.

Science.gov (United States)

Ross, Kathryn C; Juliano, Laura M

2016-05-01

of respiratory tract sensations and other rewarding effects were all diminished when smoking through the topography device. The effects of using a smoking topography device on the smoking experience should be considered when it is used in future research. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Physiological assessment of coronary lesion severity: fractional flow reserve versus nonhyperaemic indices.

Science.gov (United States)

Robertson, Keith E; Hennigan, Barry; Berry, Colin; Oldroyd, Keith G

2015-08-01

Coronary angiography alone cannot accurately identify the haemodynamic impact of a coronary artery stenosis. Current international guidelines for myocardial revascularization recommend that inducible ischaemia should be demonstrated before the consideration of percutaneous coronary intervention. Invasive physiological assessment of coronary stenosis severity has increasingly been utilized for this purpose and use of the best validated technique, fractional flow reserve (FFR), has been shown to improve clinical outcomes in patients with stable and unstable coronary artery disease. This has led to the use of FFR being recommended in international revascularization guidelines, despite which, clinical uptake has been limited. One potential reason for slow adoption has been the requirement for maximal hyperaemia at the time of FFR measurement, usually achieved by the administration of pharmacological vasodilators such as adenosine. In some healthcare systems, adenosine is expensive and, in addition, its use can be associated with significant, albeit transient, adverse effects that patients (and some operators) find uncomfortable. Consequently, several methods of nonhyperaemic lesion assessment and their potential role in decision making have been reported. In this review we will review and discuss the current evidence for hyperaemic and nonhyperaemic methods of lesion assessment. We will also look at hybrid strategies that utilize both hyperaemic and nonhyperaemic methods as a means of potentially maintaining diagnostic accuracy while minimizing the requirement for adenosine administration and discuss whether or not they represent viable clinical alternatives.

ABO blood type is associated with ovarian reserve in Chinese women with subfertility.

Science.gov (United States)

Mu, Liangshan; Jin, Wumin; Yang, Haiyan; Chen, Xia; Pan, Jiexue; Lin, Jia; Wang, Peiyu; Huang, Xuefeng

2016-08-09

Ovarian reserve reflects both the quantity and quality of oocytes available for procreation, and is affected by many known and unknown factors. ABO blood type is related to a number of infertility processes, but it is unclear whether and how ABO blood type affects ovarian reserve. Here, we explored the relationship between ABO blood type and ovarian reserve in Chinese women with subfertility. Day-3 serum follicle-stimulating hormone (FSH) levels and blood type were examined in 14,875 women who underwent IVF or ICSI treatment. Blood type proportions in the patient population were as follows: 30.98% type A, 24.54% type B, 7.57% type AB, and 36.91% type O. A higher percentage of women with diminished ovarian reserve (DOR) were blood type O, while a lower percentage had the B antigen (B and AB). Multiple logistic regression analysis revealed that blood type O was associated with a greater risk of DOR than blood type B and B antigen-positive types. By contrast, the B antigen (B and AB) was associated with a lower incidence of DOR than blood type O. These results suggest that blood type O is a risk factor for DOR while the B antigen (blood type B or AB) is a protective factor for ovarian reserve in Chinese women with subfertility. Further studies are needed to confirm this effect and identify the underlying mechanisms.

6-Gingerol alleviates exaggerated vasoconstriction in diabetic rat aorta through direct vasodilation and nitric oxide generation

Directory of Open Access Journals (Sweden)

Ghareib SA

2015-11-01

Full Text Available Salah A Ghareib,1 Hany M El-Bassossy,1,2 Ahmed A Elberry,3,4 Ahmad Azhar,5 Malcolm L Watson,6 Zainy Mohammed Banjar7 1Department of Pharmacology and Toxicology, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia; 2Department of Pharmacology, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt; 3Department of Clinical Pharmacy, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia; 4Department of Pharmacology, Faculty of Medicine, Beni Suef University, Beni Suef, Egypt; 5Department of Pediatric Cardiology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia; 6Department of Pharmacy and Pharmacology, University of Bath, Bath, UK; 7Department of Clinical Biochemistry, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia Abstract: The aim of the present study is to investigate the effect and potential mechanism of action of 6-gingerol on alterations of vascular reactivity in the isolated aorta from diabetic rats. Male Wistar rats were divided into two experimental groups, control and diabetics. Diabetes was induced by a single intraperitoneal injection of streptozotocin (50 mg kg-1, and the rats were left for 10 weeks to develop vascular complications. The effect of in vitro incubation with 6-gingerol (0.3–3 µM on the vasoconstrictor response of the isolated diabetic aortae to phenylephrine and the vasodilator response to acetylcholine was examined. Effect of 6-gingerol was also examined on aortae incubated with methylglyoxal as an advanced glycation end product (AGE. To investigate the mechanism of action of 6-gingerol, the nitric oxide synthase inhibitor Nω-nitro-L-arginine methyl ester hydrochloride (100 µM, guanylate cyclase inhibitor methylene blue (5 µM, calcium-activated potassium channel blocker tetraethylammonium chloride (10 mM, and cyclooxygenase inhibitor indomethacin (5 µM were added 30 minutes before assessing the direct vasorelaxant effect of 6

Endothelium depen dent factors of vasoconstriction (thromboxane B2 and vasodilation (6-prostaglandin F1α in children with primary arterial hype rten sion

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Yu riy V. Marushko

2015-09-01

Full Text Available Background: Vasoconstrictor and vasodilator substances imbalance play a major role in the formation of arterial hypertension. But the ratio between thromboxane B2 and 6-prostaglandin F1α in children with various forms of primary arterial hypertension (PAH are insufficiently studied. Aim of the study: to explore the features of the content of thromboxane B2, 6-keto-PGF-1alfa and their correlation in children with different clinical and pathogenetic forms of PAH. Material and methods: The study involved 83 children aged 9 to 17 years. The first group included 32 children with stable PAH, the second – 32 children with labile PAH, the third (control group – 21 children with normal blood pressure. TXB2 and 6-PGF1α serum levels were investigated by ELISA. All children were held ambulatory blood pressure monitoring (ABPM. Results: Average TXB2 levels in boys were 25,05 ±6,43 ng/ml at stable PAH and 27,26 ±11,26 ng/ml at labile PAH, which exceeded their levels in the control group (p < 0,05. Girls’ TXB2 level was elevated at labile PAH (to 11,06 ±1,79 ng/ml, p < 0,05 and did not differ from the control group at stable PAH. Girls’ 6-PGF1α level was up to 3,41 ±0,52 ng/ml at stable PAH and up to 2,63 ±0,25 ng/ml at labile PAH. Conclusions: Violation of the ratio between endothelial vasoconstriction (thromboxane and vasodilatation (prostacyclin factors in boys with PAH is due to increased TXB2 levels compared with children with normal blood pressure (p < 0,05. Girls with PAH have better compensatory vasodilation opportunities compared with boys according to increased prostacyclin production. That prevents the progression of endothelial dysfunction and PAH stabilization in girls.

Pulmonary Hypertension and Pulmonary Vasodilators.

Science.gov (United States)

Keller, Roberta L

2016-03-01

Pulmonary hypertension in the perinatal period can present acutely (persistent pulmonary hypertension of the newborn) or chronically. Clinical and echocardiographic diagnosis of acute pulmonary hypertension is well accepted but there are no broadly validated criteria for echocardiographic diagnosis of pulmonary hypertension later in the clinical course, although there are significant populations of infants with lung disease at risk for this diagnosis. Contributing cardiovascular comorbidities are common in infants with pulmonary hypertension and lung disease. It is not clear who should be treated without confirmation of pulmonary vascular disease by cardiac catheterization, with concurrent evaluation of any contributing cardiovascular comorbidities. Copyright © 2016 Elsevier Inc. All rights reserved.

Metabolic Evidence of Diminished Lipid Oxidation in Women With Polycystic Ovary Syndrome

OpenAIRE

Whigham, Leah D.; Butz, Daniel E.; Dashti, Hesam; Tonelli, Marco; Johnson, LuAnn K.; Cook, Mark E.; Porter, Warren P.; Eghbalnia, Hamid R.; Markley, John L.; Lindheim, Steven R.; Schoeller, Dale A.; Abbott, David H.; Assadi-Porter, Fariba M.

2014-01-01

Polycystic ovary syndrome (PCOS), a common female endocrinopathy, is a complex metabolic syndrome of enhanced weight gain. The goal of this pilot study was to evaluate metabolic differences between normal (n=10) and PCOS (n=10) women via breath carbon isotope ratio, urinary nitrogen and nuclear magnetic resonance (NMR)-determined serum metabolites. Breath carbon stable isotopes measured by cavity ring down spectroscopy (CRDS) indicated diminished (p

RECOMMENDATION OF FERTILIZERS BASED ON THE LAW OF DIMINISHING RETURN

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Geicimara Guimarães

2011-07-01

Full Text Available The objective of this work was to demonstrate the viability of making recommendation of fertilizers for corn and bean cultures based on models of saturation kinetics, following the Law of diminishing return, aiming to improve the efficiency of nutrient use, reducing the costs of production and avoiding the excessive use of non renewable natural resources. In the corn culture (grain hybrid they were utilized levels of 0.0, 0.25, 0.5, 1, 2, 4, 8, 16 and 32 g/hole of fertilizer NPK 4-14-8 in seeding and same amounts of ammonium sulfate 34 days later. The space between plants was of 20 x 70 cm (71.429 plants/hectare, with eight replicates per each level, totalizing 72 plants in the experimental area. In bean culture (red variety they were utilized levels of 0.0, 0.25, 0.50, 1, 2, 4, 8, 16 and 32 g/hole of NPK 4-14-8 in planting. The space between plants was of 20 x 50 cm, with two grains per hole (71.429 plants/hectare, with eight holes per each level, totalizing 144 plants in the experimental area. The models of saturation kinetics of Lineweaver-Burk presented good adjustments for responses of corn and beans to fertilization, following the Law of diminishing return, in which 4 to 8 g of fertilizer per hole caused good part of the productive response for corn and 2 grams for bean. The employee of moderate level of fertilization leads to a more sustainable and economically viable agriculture to the household producer.

Enhancing hippocampal blood flow after cerebral ischemia and vasodilating basilar arteries: in vivo and in vitro neuroprotective effect of antihypertensive DDPH

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Li Sun

2015-01-01

Full Text Available 1-(2,6-Dimethylphenoxy-2-(3,4-dimethoxyphenylethylamino-propane hydrochloride (DDPH is a novel antihypertensive agent based on structural characteristics of mexiletine and verapamine. We investigated the effect of DDPH on vasodilatation and neuroprotection in a rat model of cerebral ischemia in vivo, and a rabbit model of isolated basilar arteries in vitro. Our results show that DDPH (10 mg/kg significantly increased hippocampal blood flow in vivo in cerebral ischemic rats, and exerted dose-dependent relaxation of isolated basilar arteries contracted by histamine or KCl in the in vitro rabbit model. DDPH (3 × 10 -5 M also inhibited histamine-stimulated extracellular calcium influx and intracellular calcium release. Our findings suggest that DDPH has a vasodilative effect both in vivo and in vitro, which mediates a neuroprotective effect on ischemic nerve tissue.

Data describing the flow-mediated vasodilation responses and blood pressure in young adult humans after a single dose of oral edible emu oil

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Tadayoshi Miyashita

2018-04-01

Full Text Available The data provided herein include flow-mediated vasodilation responses, represented by changes in arterial diameter, and blood pressure in young adults after a single oral dose of edible emu oil or placebo (cross-over design. Ten healthy men and 10 healthy women participated. Increased blood flow in the antebrachial region was induced by inflating a pressure cuff and subsequently releasing the pressure by deflating the cuff. After the release, the arterial diameter was continuously monitored for 110 sec using ultrasonic diagnostic equipment. The changes in the arterial diameter from 20 to 110 sec post-cuff deflation are described in line graphs and tables. In addition, systolic and diastolic blood pressure data are provided in a table.

Selection of Parasites with Diminished Drug Sensitivity by Amodiaquine-Containing Antimalarial Regimens in Uganda

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Nawaz, Fatima; Nsobya, Samuel L.; Kiggundu, Moses; Joloba, Moses; Rosenthal, Philip J.

2009-01-01

Background Amodiaquine (AQ) is paired with artesunate (AS) or sulfadoxine-pyrimethamine (SP) in recommended antimalarial regimens. It is unclear how readily AQ resistance will be selected with combination chemotherapy. Methods We collected 61 Plasmodium falciparum samples from a cohort of Ugandan children randomized to treatment with AQ/SP, AS/AQ, or artemether-lumefantrine (AL) for uncomplicated malaria. In vitro sensitivity to monodesethylamodiaquine (MDAQ) was measured with a histidine rich protein-2-based ELISA, and potential resistance-mediating polymorphisms pfmdr-1were evaluated. Results Parasites from subjects previously treated with AQ/SP or AS/AQ within 12 weeks were less sensitive to MDAQ (n=18; mean IC50 62.9 nM; range 12.7–158.3 nM) than parasites from those not treated within 12 weeks (n=43; mean IC50 37.5 nM; range 6.3–184.7 nM; p=0.0085) or only those in the treatment arm that did not contain AQ (n=20; mean IC50 28.8 nM; range 6.3–121.8 nM; p=0.0042). The proportion of strains with polymorphisms expected to mediate diminished response to AQ (pfmdr-1 86Y and 1246Y) increased after prior AQ therapy, although differences were not significant. Conclusions Prior therapy selected for diminished response to MDAQ, suggesting that AQ-containing regimens may rapidly lose efficacy in Africa. The mechanism of diminished MDAQ response is not fully explained by known mutations in pfmdr-1. PMID:19905933

Diminishing Footprints: Exploring the Local and Global Challenges to Place-Based Environmental Education

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Chang, David

2017-01-01

An efficacious response to the ecological crisis requires a thorough examination of our material entitlements and a willingness to reduce our ecological impact by diminishing current levels of consumption. Drawing on the example of air pollution in China, I present a case for the reduction of consumption and impact as a worthy outcome of…

Elements to diminish radioactive accidents; Elementos para disminuir accidentes radiactivos

Energy Technology Data Exchange (ETDEWEB)

Cortes I, M.E.; Ramirez G, F.P. [Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas 152, C.P. 07730 Mexico D.F. (Mexico)

1998-12-31

In this work it is presented an application of the cause-effect diagram method or Ichikawa method identifying the elements that allow to diminish accidents when the radioactive materials are transported. It is considered the transport of hazardous materials which include radioactive materials in the period: December 1996 until March 1997. Among the identified elements by this method it is possible to mention: the road type, the radioactive source protection, the grade driver responsibility and the preparation that the OEP has in the radioactive material management. It is showed the differences found between the country inner roads and the Mexico City area. (Author)

Epstein-Barr virus reactivation associated with diminished cell-mediated immunity in antarctic expeditioners

Science.gov (United States)

Mehta, S. K.; Pierson, D. L.; Cooley, H.; Dubow, R.; Lugg, D.

2000-01-01

Epstein-Barr virus (EBV) reactivation and cell-mediated immune (CMI) responses were followed in 16 Antarctic expeditioners during winter-over isolation at 2 Australian National Antarctic Research Expedition stations. Delayed-type hypersensitivity (DTH) skin testing was used as an indicator of the CMI response, that was evaluated 2 times before winter isolation and 3 times during isolation. At all 5 evaluation times, 8 or more of the 16 subjects had a diminished CMI response. Diminished DTH was observed on every test occasion in 4/16 subjects; only 2/16 subjects exhibited normal DTH responses for all 5 tests. A polymerase chain reaction (PCR) assay was used to detect EBV DNA in saliva specimens collected before, during, and after the winter isolation. EBV DNA was present in 17% (111/642) of the saliva specimens; all 16 subjects shed EBV in their saliva on at least 1 occasion. The probability of EBV shedding increased (P = 0.013) from 6% before or after winter isolation to 13% during the winter period. EBV appeared in saliva during the winter isolation more frequently (P viruses.

Diminished Antimicrobial Peptide and Antifungal Antibiotic Activities against Candida albicans in Denture Adhesive

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Amber M. Bates

2017-02-01

Full Text Available The underlying causes of denture stomatitis may be related to the long-term use of adhesives, which may predispose individuals to oral candidiasis. In this study, we hypothesize that antimicrobial peptides and antifungal antibiotics have diminished anti-Candida activities in denture adhesive. To show this, nine antimicrobial peptides and five antifungal antibiotics with and without 1.0% denture adhesive were incubated with Candida albicans strains ATCC 64124 and HMV4C in radial diffusion assays. In gels with 1.0% adhesive, HNP-1, HBD2, HBD3, IP-10, LL37 (only one strain, histatin 5 (only one strain, lactoferricin B, and SMAP28 showed diminished activity against C. albicans. In gels with 1.0% adhesive, amphotericin B and chlorhexidine dihydrochloride were active against both strains of C. albicans. These results suggest that denture adhesive may inactivate innate immune mediators in the oral cavity increasing the risk of C. albicans infections, but inclusion of antifungal antibiotics to denture adhesive may aid in prevention or treatment of Candida infections and denture stomatitis.

alpha-adrenergic Blockade Unmasks a Greater Compensatory Vasodilation in Hypoperfused Contracting Muscle

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Darren P. Casey

2012-07-01

Full Text Available We previously demonstrated that acute hypoperfusion in exercising human muscle causes an immediate increase in vascular resistance that is followed by a partial restoration (less than 100% recovery of flow. In the current study we examined the contribution of alpha-adrenergic vasoconstriction in the initial changes in vascular resistance at the onset of hypoperfusion as well as in the recovery of flow over time. Nine healthy male subjects (29 ± 2 performed rhythmic forearm exercise (20% of maximum during hypoperfusion evoked by intra-arterial balloon inflation. Each trial included; baseline, exercise prior to inflation, exercise with inflation, and exercise after deflation (3 min each. Forearm blood flow (FBF; ultrasound, local (brachial artery, and systemic arterial pressure (MAP; Finometer were measured. The trial was repeated during phentolamine infusion (alpha-adrenergic receptor blockade. Forearm vascular conductance (FVC; ml min-1 100 mmHg-1 and resistance (mmHg ml min-1 was calculated from BF (ml min-1 and local MAP (mmHg. Recovery of FBF and FVC (steady state inflation plus exercise value – nadir/ [steady state exercise (control value-nadir] with phentolamine was enhanced compared with the respective control (no drug trial (FBF = 97 ± 5% vs. 81 ± 6%, P < 0.05; FVC = 126 ± 9% vs. 91 ± 5%, P < 0.01. However, the absolute (0.05 ± 0.01 vs. 0.06 ± 0.01 mmHg ml min-1; P = 0.17 and relative (35 ± 5% vs. 31 ± 2%; P = 0.41 increase in vascular resistance at the onset of balloon inflation was not different between the alpha-adrenergic receptor inhibition and control (no drug trials. Therefore, our data indicate that alpha-adrenergic mediated vasoconstriction restricts compensatory vasodilation during forearm exercise with hypoperfusion, but is not responsible for the initial increase in vascular resistance at the onset of hypoperfusion.

Intrinsic washout rates of thallium-201 in normal and ischemic myocardium after dipyridamole-induced vasodilation

International Nuclear Information System (INIS)

Beller, G.A.; Holzgrefe, H.H.; Watson, D.D.

1985-01-01

Infusion of dipyridamole has been suggested as an alternative to exercise stress for myocardial perfusion imaging for detection of ischemia, but the mechanism and significance of thallium-201 ( 201 Tl) redistribution after administration of dipyridamole are uncertain. If disparate intrinsic cellular efflux rates of 201 Tl from normal and relatively underperfused myocardium in response to dipyridamole-induced vasodilation were observed, this could explain delayed 201 Tl redistribution. We investigated the effect of an intravenous infusion of 0.15 mg/kg dipyridamole on the intrinsic myocardial washout rate of 201 Tl as measured with a gamma-detector probe after intracoronary injection (50 muCi) of the radionuclide in open-chested anesthetized dogs. In six normal dogs the t 1/2 for intrinsic 201 Tl washout from the myocardium was 89 +/- 11 min (SE) at control conditions and became more rapid at 59 +/- 10 min (p . .0001) after dipyridamole. This corresponded to a significant increase in microsphere-determined epicardial (0.95 +/- 0.11 to 2.23 +/- 0.46 ml/min/g; p . .01) and endocardial (0.86 +/- 0.10 to 1.53 +/- 0.27; p . .029) flows. In 12 dogs with a critical coronary stenosis, the 201 Tl intrinsic washout rate slowed from 70 +/- 5 to 104 +/- 6 min (p . .0001) after production of the stenosis and slowed even further to 169 +/- 21 min (p . .003) after dipyridamole

Effects of Buddhism walking meditation on depression, functional fitness, and endothelium-dependent vasodilation in depressed elderly.

Science.gov (United States)

Prakhinkit, Susaree; Suppapitiporn, Siriluck; Tanaka, Hirofumi; Suksom, Daroonwan

2014-05-01

The objectives of this study were to determine the effects of the novel Buddhism-based walking meditation (BWM) and the traditional walking exercise (TWE) on depression, functional fitness, and vascular reactivity. This was a randomized exercise intervention study. The study was conducted in a university hospital setting. Forty-five elderly participants aged 60-90 years with mild-to-moderate depressive symptoms were randomly allocated to the sedentary control, TWE, and BWM groups. The BWM program was based on aerobic walking exercise incorporating the Buddhist meditations performed 3 times/week for 12 weeks. Depression score, functional fitness, and endothelium-dependent vasodilation as measured by the flow-mediated dilation (FMD) were the outcome measures used. Muscle strength, flexibility, agility, dynamic balance, and cardiorespiratory endurance increased in both exercise groups (p<0.05). Depression score decreased (p<0.05) only in the BWM group. FMD improved (p<0.05) in both exercise groups. Significant reduction in plasma cholesterol, triglyceride, high-density lipoprotein cholesterol, and C-reactive protein were found in both exercise groups, whereas low-density lipoprotein cholesterol, cortisol, and interleukin-6 concentrations decreased only in the BWM group. Buddhist walking meditation was effective in reducing depression, improving functional fitness and vascular reactivity, and appears to confer greater overall improvements than the traditional walking program.

Impact of a program to diminish gender insensitivity and sexual harassment at a medical school.

Science.gov (United States)

Jacobs, C D; Bergen, M R; Korn, D

2000-05-01

To measure the effect of an intervention to reduce gender insensitivity and sexual harassment at one medical school. Stanford University School of Medicine undertook a multifaceted program to educate faculty and students regarding gender issues and to diminish sexual harassment. The authors developed a survey instrument to assess the faculty's perceptions regarding environment (five scales) and incidences of sexual harassment. Faculty were surveyed twice during the interventions (1994 and 1995). Between the two years, the authors measured significant improvements in mean ratings for positive climate (p = .004) and cohesion (p = .006) and decreases in the faculty's perceptions of sexual harassment (p = 0006), gender insensitivity (p = .001), and gender discrimination (p = .004). The faculty also reported fewer observations of harassing behavior during the study period. An intervention program to diminish gender insensitivity and sexual harassment can measurably improve a medical school's environment.

Diclofenac Prolongs Repolarization in Ventricular Muscle with Impaired Repolarization Reserve

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Kristóf, Attila; Husti, Zoltán; Koncz, István; Kohajda, Zsófia; Szél, Tamás; Juhász, Viktor; Biliczki, Péter; Jost, Norbert; Baczkó, István; Papp, Julius Gy; Varró, András; Virág, László

2012-01-01

Background The aim of the present work was to characterize the electrophysiological effects of the non-steroidal anti-inflammatory drug diclofenac and to study the possible proarrhythmic potency of the drug in ventricular muscle. Methods Ion currents were recorded using voltage clamp technique in canine single ventricular cells and action potentials were obtained from canine ventricular preparations using microelectrodes. The proarrhythmic potency of the drug was investigated in an anaesthetized rabbit proarrhythmia model. Results Action potentials were slightly lengthened in ventricular muscle but were shortened in Purkinje fibers by diclofenac (20 µM). The maximum upstroke velocity was decreased in both preparations. Larger repolarization prolongation was observed when repolarization reserve was impaired by previous BaCl2 application. Diclofenac (3 mg/kg) did not prolong while dofetilide (25 µg/kg) significantly lengthened the QTc interval in anaesthetized rabbits. The addition of diclofenac following reduction of repolarization reserve by dofetilide further prolonged QTc. Diclofenac alone did not induce Torsades de Pointes ventricular tachycardia (TdP) while TdP incidence following dofetilide was 20%. However, the combination of diclofenac and dofetilide significantly increased TdP incidence (62%). In single ventricular cells diclofenac (30 µM) decreased the amplitude of rapid (IKr) and slow (IKs) delayed rectifier currents thereby attenuating repolarization reserve. L-type calcium current (ICa) was slightly diminished, but the transient outward (Ito) and inward rectifier (IK1) potassium currents were not influenced. Conclusions Diclofenac at therapeutic concentrations and even at high dose does not prolong repolarization markedly and does not increase the risk of arrhythmia in normal heart. However, high dose diclofenac treatment may lengthen repolarization and enhance proarrhythmic risk in hearts with reduced repolarization reserve. PMID:23300901

Family Structure and Subsequent Anxiety Symptoms; Minorities’ Diminished Return

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Shervin Assari

2018-05-01

Full Text Available Background: Minorities’ Diminished Return (MDR theory suggests that socioeconomic position (SEP may have a smaller effect on health and well-being of members of the minority than the majority groups. Aim: Built on the MDR theory, this study compared Whites and African Americans for the effects of three family SEP indicators (family type, parental education, and parental employment during adolescence on subsequent symptoms of anxiety 18 years later during young adulthood. Methods: Flint Adolescents Study (FAS, 1994–2012, followed 359 youth (ages 13 to 17, 295 African American and 64 Whites for 18 years. The independent variables were family type, parental education, and parental employment during adolescence. The dependent variable was subsequent symptoms of anxiety, measured using the Brief Symptom Inventory (BSI, 18 years later. Age and gender were the covariates and race/ethnicity was the focal effect modifier (moderator. Four linear regression models were estimated to investigate the effects of the three family SEP indicators at age 15 on subsequent symptoms of anxiety at age 33 in the pooled sample and also by race/ethnicity. Results: In the pooled sample, having married parents at age 15 was inversely associated with symptoms of anxiety at age 33. We found an interaction between race/ethnicity and family type, indicating a smaller protective effect of having married parents against symptoms of anxiety for African American compared to White participants. The other two SEP indicators did not show any effect and did not interact with race/ethnicity on the outcome. Conclusion: In support of the MDR theory, marital status of parents during adolescence protects White but not African American young adults against anxiety symptoms. Diminished return of SEP is one of many underlying mechanisms involved in shaping racial and ethnic disparities in anxiety, however, that is often overlooked. Future research that examines economic and social

Jabuticaba-Induced Endothelium-Independent Vasodilating Effect on Isolated Arteries.

Science.gov (United States)

Andrade, Daniela Medeiros Lobo de; Borges, Leonardo Luis; Torres, Ieda Maria Sapateiro; Conceição, Edemilson Cardoso da; Rocha, Matheus Lavorenti

2016-09-01

Despite the important biological effects of jabuticaba, its actions on the cardiovascular system have not been clarified. To determine the effects of jabuticaba hydroalcoholic extract (JHE) on vascular smooth muscle (VSM) of isolated arteries. Endothelium-denuded aortic rings of rats were mounted in isolated organ bath to record isometric tension. The relaxant effect of JHE and the influence of K+ channels and Ca2+ intra- and extracellular sources on JHE-stimulated response were assessed. Arteries pre-contracted with phenylephrine showed concentration-dependent relaxation (0.380 to 1.92 mg/mL). Treatment with K+ channel blockers (tetraethyl-ammonium, glibenclamide, 4-aminopyridine) hindered relaxation due to JHE. In addition, phenylephrine-stimulated contraction was hindered by previous treatment with JHE. Inhibition of sarcoplasmic reticulum Ca2+ ATPase did not change relaxation due to JHE. In addition, JHE inhibited the contraction caused by Ca2+ influx stimulated by phenylephrine and KCl (75 mM). JHE induces endothelium-independent vasodilation. Activation of K+ channels and inhibition of Ca2+ influx through the membrane are involved in the JHE relaxant effect. Embora a jabuticaba apresente importantes efeitos biológicos, suas ações sobre o sistema cardiovascular ainda não foram esclarecidas. Determinar os efeitos do extrato de jabuticaba (EHJ) sobre o músculo liso vascular (MLV) em artérias isoladas. Aortas (sem endotélio) de ratos foram montadas em banho de órgãos isolados para registro de tensão isométrica. Foram verificados o efeito relaxante, a influência dos canais de K+ e das fontes de Ca2+ intra- e extracelular sob a resposta estimulada pelo EHJ. Artérias pré-contraídas com fenilefrina apresentaram relaxamento concentração-dependente (0,380 a 1,92 mg/mL). O tratamento com bloqueadores de canais de K+ (tetraetilamônio, glibenclamida, 4-aminopiridina) prejudicaram o relaxamento pelo EHJ. A contração estimulada com fenilefrina tamb

Alterations of cerebral blood flow and cerebrovascular reserve in patients with chronic traumatic brain injury accompanying deteriorated intelligence

International Nuclear Information System (INIS)

Song, Ho Chun; Bom, Hee Seung

2000-01-01

The purpose of this study was to evaluate alterations of regional cerbral blood flow (CBF) and cerebrovascular reserve (CVR), and correlation between these alternations and cognitive dysfunctin in patients with chronic traumatic brain injury (TBI) and normal brain MRI findings. Thirty TBI patients and 19 healthy volunteers underwent rest/acetazolaminde brain SPECT using Tc-99m HMPAO. Korean-Wechsler Adult Intelligence scale test was also performed in the patient group. Statistical analysis was performed with statistical parametric mapping software (SPM '97). CBF was diminished in the left hemisphere including Wernicke's area in all patients with lower verbal scale scores. In addition, a reduction in CBF in the right frontal, temporal and parietal cortices was related with depressed scores in information, digital span, arithmetic and similarities. In patients with lower performance scale scores, CBF was mainly diminished in the right hemisphere including superior temporal and supramarginal gyri, premotor, primary somatomotor and a part of prefrontal cortices, left frontal lobe and supramarginal gyrus. CVR was diminished in sixty-four Brodmann's areas compared to control. A reduction in CVR was demonstrated bilaterally in the frontal and temporal lobes in patients with lower scores in both verbal and performance tests, and in addition, both inferior parietal and occipital lobes in information subset. Alterations of CBF and CVR were demonstrated in the symptomatic TBI patients with normal MRI finding. These alterations were correlated with the change of intelligence, of which the complex functions are subserved by multiple interconnected cortical structures.=20

Diminished alternative reinforcement as a mechanism linking conduct problems and substance use in adolescence: a longitudinal examination.

Science.gov (United States)

Khoddam, Rubin; Cho, Junhan; Jackson, Nicholas J; Leventhal, Adam M

2018-06-01

To determine whether diminished alternative reinforcement (i.e. engagement and enjoyment from substance-free activities) mediated the longitudinal association of conduct problems with substance use in early-mid-adolescence. Structural equation modeling tested whether the association between wave 1 (baseline) conduct problems and wave 3 (24-month follow-up) substance use outcomes was mediated by diminished alternative reinforcement at wave 2 (12-month follow-up). Additional analyses tested whether sex and socio-economic status moderated this association. Ten high schools in Los Angeles, CA, USA, 2013-15. Students (n = 3396, 53.5% female, mean [standard deviation (SD)] age at wave 1 baseline = 14.1 (0.42) years). Self-reported conduct problems (11-item questionnaire), alternative reinforcement (44-item questionnaire) and use of alcohol, marijuana and combustible cigarettes during the past 6 months (yes/no) and the past 30 days (nine-level ordinal response based on days used in past 30 days). Significant associations of wave 1 conduct problems with wave 3 marijuana use during the past 6 months (β = 0.25) and past 30 days (β = 0.26) were mediated by wave 2 diminished alternative reinforcement (β indirect effect : 6 months = 0.013, 30 days = 0.017, Ps alternative reinforcement. All associations did not differ by sex and socio-economic status. Diminished alternative reinforcement may be a modifiable mechanism linking early adolescent conduct problems and subsequent marijuana use that could be targeted in prevention programs to offset the adverse health and social sequelae associated with comorbid conduct problems and marijuana use in early-mid adolescence. © 2018 Society for the Study of Addiction.

Diminishing musyarakah investment model based on equity

Science.gov (United States)

Jaffar, Maheran Mohd; Zain, Shaharir Mohamad; Jemain, Abdul Aziz

2017-11-01

Most of the mudharabah and musyarakah contract funds are involved in debt financing. This does not support the theory that profit sharing contract is better than that of debt financing due to the sharing of risks and ownership of equity. Indeed, it is believed that Islamic banking is a financial model based on equity or musyarakah which emphasis on the sharing of risks, profit and loss in the investment between the investor and entrepreneur. The focus of this paper is to introduce the mathematical model that internalizes diminishing musyarakah, the sharing of profit and equity between entrepreneur and investor. The entrepreneur pays monthly-differed payment to buy out the equity that belongs to the investor (bank) where at the end of the specified period, the entrepreneur owns the business and the investor (bank) exits the joint venture. The model is able to calculate the amount of equity at any time for both parties and hence would be a guide in helping to estimate the value of investment should the entrepreneur or investor exit before the end of the specified period. The model is closer to the Islamic principles for justice and fairness.

Diminished insulin-mediated forearm blood flow and muscle glucose uptake in young men with low birth weight

DEFF Research Database (Denmark)

Sonne, M P; Højbjerre, L; Alibegovic, A C

2009-01-01

BACKGROUND: Low birth weight (LBW) is associated with increased risk of type 2 diabetes and cardiovascular disease. We studied endothelial function and insulin sensitivity in young men with LBW (n = 22) and controls (n = 22). METHODS: Insulin sensitivity and endothelial function was studied...... with venous occlusion plethysmography and intra-arterial infusions of adenosine and acetylcholine, before and during a hyperinsulinemic isoglycemic clamp. RESULTS: Forearm blood flow response to systemic hyperinsulinemia was diminished in LBW compared to controls (p ... extraction was similar, and consequently insulin-stimulated forearm glucose clearance was diminished in LBW compared with controls (0.8 +/- 0.09 vs. 1.4 +/- 0.36 ml x 100 ml(-1) x min(-1), respectively, p

Cerebrovascular mental stress reactivity is impaired in hypertension

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Naqvi Tasneem Z

2009-07-01

Full Text Available Abstract Background Brachial artery reactivity in response to shear stress is altered in subjects with hypertension. Since endothelial dysfunction is generalized, we hypothesized that carotid artery (CA reactivity would also be altered in hypertension. Purpose To compare (CA endothelium-dependent vasodilation in response to mental stress in normal and hypertensive subjects. Methods We evaluated CA reactivity to mental stress in 10 young healthy human volunteers (aged 23 ± 4 years, 20 older healthy volunteers (aged 49 ± 11 years and in 28 patients with essential hypertension (aged 51 ± 13 years. In 10 healthy volunteers and 12 hypertensive subjects, middle cerebral artery (MCA PW transcranial Doppler was performed before and 3 minutes after mental stress. Results Mental stress by Stroop color word conflict, math or anger recall tests caused CA vasodilation in young healthy subjects (0.61 ± 0.06 to 0.65 ± 0.07 cm, p Conclusion Mental stress produces CA vasodilation and is accompanied by an increase in CA and MCA blood flow in healthy subjects. This mental stress induced CA vasodilation and flow reserve is attenuated in subjects with hypertension and may reflect cerebral vascular endothelial dysfunction. Assessment of mental stress induced CA reactivity by ultrasound is a novel method for assessing the impact of hypertension on cerebrovascular endothelial function and blood flow reserve.

Progesterone up-regulates vasodilator effects of calcitonin gene-related peptide in N(G)-nitro-L-arginine methyl ester-induced hypertension.

Science.gov (United States)

Gangula, P R; Wimalawansa, S J; Yallampalli, C

1997-04-01

We recently reported that calcitonin gene-related peptide can reverse the hypertension produced by N(G)-nitro-L-arginine methyl ester in pregnant rats. In the current study we investigated whether these vasodilator effects of calcitonin gene-related peptide were progesterone dependent. Calcitonin gene-related peptide or N(G)-nitro-L-arginine methyl ester was infused through osmotic minipumps, either separately or in combination, to groups of five pregnant rats from day 17 of gestation until day 8 post partum or to nonpregnant ovariectomized rats for 8 days. Progesterone was injected during days 1 to 6 post partum and for 6 days after ovariectomy. Systolic blood pressure was measured daily. Animals receiving N(G)-nitro-L-arginine methyl ester exhibited significant elevations of blood pressure during pregnancy and post partum. Coadministration of calcitonin gene-related peptide to these rats reversed the hypertension during pregnancy but not during the postpartum period. At the dose used in this study calcitonin gene-related peptide administered alone was without significant effects on blood pressure. However, it reduced both the mortality and growth restriction of the fetus associated with N(G)-nitro-L-arginine methyl ester in these animals. Calcitonin gene-related peptide reversed the hypertension in N(G)-nitro-L-arginine methyl ester-infused postpartum rats during the periods of progesterone treatment only, and these effects were lost when progesterone treatment was stopped. Neither progesterone nor calcitonin gene-related peptide alone were effective. To further confirm these observations, progesterone effects were tested in ovariectomized adult rats. Similar to the findings in postpartum rats, calcitonin gene-related peptide completely reversed the elevation in blood pressure in N(G)-nitro-L-arginine methyl ester-treated rats receiving progesterone injections. The effects of calcitonin gene-related peptide were apparent only during the progesterone treatment

The immune receptor Trem1 cooperates with diminished DNA damage response to induce preleukemic stem cell expansion.

Science.gov (United States)

Du, W; Amarachintha, S; Wilson, A; Pang, Q

2017-02-01

Fanconi anemia (FA) is an inherited bone marrow failure syndrome with extremely high risk of leukemic transformation. Here we investigate the relationship between DNA damage response (DDR) and leukemogenesis using the Fanca knockout mouse model. We found that chronic exposure of the Fanca -/- hematopoietic stem cells to DNA crosslinking agent mitomycin C in vivo leads to diminished DDR, and the emergence/expansion of pre-leukemia stem cells (pre-LSCs). Surprisingly, although genetic correction of Fanca deficiency in the pre-LSCs restores DDR and reduces genomic instability, but fails to prevent pre-LSC expansion or delay leukemia development in irradiated recipients. Furthermore, we identified transcription program underlying dysregulated DDR and cell migration, myeloid proliferation, and immune response in the Fanca -/- pre-LSCs. Forced expression of the downregulated DNA repair genes, Rad51c or Trp53i13, in the Fanca -/- pre-LSCs partially rescues DDR but has no effect on leukemia, whereas shRNA knockdown of the upregulated immune receptor genes Trem1 or Pilrb improves leukemia-related survival, but not DDR or genomic instability. Furthermore, Trem1 cooperates with diminished DDR in vivo to promote Fanca -/- pre-LSC expansion and leukemia development. Our study implicates diminishing DDR as a root cause of FA leukemogenesis, which subsequently collaborates with other signaling pathways for leukemogenic transformation.

Diminished Dynamic Physical Performance Is Associated With Orthostatic Hypotension in Geriatric Outpatients.

Science.gov (United States)

de Bruïne, Eline S; Reijnierse, Esmee M; Trappenburg, Marijke C; Pasma, Jantsje H; de Vries, Oscar J; Meskers, Carel G M; Maier, Andrea B

2018-03-23

Orthostatic hypotension (OH), a blood pressure drop after postural change, is a highly prevalent and disabling syndrome in older adults. Yet, the association between physical performance and OH is not clearly established. The aim of this study was to determine whether different types of physical performance are associated with OH in a clinically relevant population of geriatric outpatients. This cross-sectional study included 280 geriatric outpatients (mean age: 82.2 years, standard deviation: 7.1). Orthostatic hypotension was determined using intermittently measured blood pressure and continuously measured blood pressure in a random subgroup of 58 patients. Physical performance was classified into a dynamic type (4-m Walk Test, Chair Stand Test, and Timed Up and Go test) and a static type (standing balance tests, handgrip strength). Associations were analyzed using logistic regression models with adjustments for age, sex, weight, and height. Diminished physical performance on the Chair Stand Test was associated with OH measured intermittently. Diminished physical performance on all dynamic physical domains (4-m Walk Test, Chair Stand Test, and Timed Up and Go test) was associated with OH measured continuously. Static physical performance was not significantly associated with OH. Dynamic physical performance tests with a substantial postural change and center of mass displacement were significantly associated with OH. The influence of physical performance on OH in daily routine activities should be further explored to establish counteracting interventions.

When is diminishment a form of enhancement? Rethinking the enhancement debate in biomedical ethics

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Brian D. Earp

2014-02-01

Full Text Available The enhancement debate in neuroscience and biomedical ethics tends to focus on the augmentation of certain capacities or functions: memory, learning, attention, and the like. Typically, the point of contention is whether these augmentative enhancements are permissible for individuals with no particular ‘medical’ disadvantage along any of the dimensions of interest. Less frequently addressed in the literature, however, is the fact that sometimes the diminishment of a capacity or function, under the right set of circumstances, could plausibly contribute to an individual’s overall well-being: more is not always better, and sometimes less is more. Such cases may be especially likely, we suggest, when trade-offs in our modern environment have shifted since the environment of evolutionary adaptation. In this article, we introduce the notion of diminishment as enhancement and go on to defend a welfarist conception of enhancement. We show how this conception resolves a number of definitional ambiguities in the enhancement literature, and we suggest that it can provide a useful framework for thinking about the use of emerging neurotechnologies to promote human flourishing.

Repeated exposure to media violence is associated with diminished response in an inhibitory frontolimbic network.

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Christopher R Kelly

Full Text Available BACKGROUND: Media depictions of violence, although often claimed to induce viewer aggression, have not been shown to affect the cortical networks that regulate behavior. METHODOLOGY/PRINCIPAL FINDINGS: Using functional magnetic resonance imaging (fMRI, we found that repeated exposure to violent media, but not to other equally arousing media, led to both diminished response in right lateral orbitofrontal cortex (right ltOFC and a decrease in right ltOFC-amygdala interaction. Reduced function in this network has been previously associated with decreased control over a variety of behaviors, including reactive aggression. Indeed, we found reduced right ltOFC responses to be characteristic of those subjects that reported greater tendencies toward reactive aggression. Furthermore, the violence-induced reduction in right ltOFC response coincided with increased throughput to behavior planning regions. CONCLUSIONS: These novel findings establish that even short-term exposure to violent media can result in diminished responsiveness of a network associated with behaviors such as reactive aggression.

Vasodilator-Stimulated Phosphoprotein Activity Is Required for Coxiella burnetii Growth in Human Macrophages.

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Punsiri M Colonne

2016-10-01

Full Text Available Coxiella burnetii is an intracellular bacterial pathogen that causes human Q fever, an acute flu-like illness that can progress to chronic endocarditis and liver and bone infections. Humans are typically infected by aerosol-mediated transmission, and C. burnetii initially targets alveolar macrophages wherein the pathogen replicates in a phagolysosome-like niche known as the parasitophorous vacuole (PV. C. burnetii manipulates host cAMP-dependent protein kinase (PKA signaling to promote PV formation, cell survival, and bacterial replication. In this study, we identified the actin regulatory protein vasodilator-stimulated phosphoprotein (VASP as a PKA substrate that is increasingly phosphorylated at S157 and S239 during C. burnetii infection. Avirulent and virulent C. burnetii triggered increased levels of phosphorylated VASP in macrophage-like THP-1 cells and primary human alveolar macrophages, and this event required the Cα subunit of PKA. VASP phosphorylation also required bacterial protein synthesis and secretion of effector proteins via a type IV secretion system, indicating the pathogen actively triggers prolonged VASP phosphorylation. Optimal PV formation and intracellular bacterial replication required VASP activity, as siRNA-mediated depletion of VASP reduced PV size and bacterial growth. Interestingly, ectopic expression of a phospho-mimetic VASP (S239E mutant protein prevented optimal PV formation, whereas VASP (S157E mutant expression had no effect. VASP (S239E expression also prevented trafficking of bead-containing phagosomes to the PV, indicating proper VASP activity is critical for heterotypic fusion events that control PV expansion in macrophages. Finally, expression of dominant negative VASP (S157A in C. burnetii-infected cells impaired PV formation, confirming importance of the protein for proper infection. This study provides the first evidence of VASP manipulation by an intravacuolar bacterial pathogen via activation of PKA

Diclofenac prolongs repolarization in ventricular muscle with impaired repolarization reserve.

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Attila Kristóf

Full Text Available BACKGROUND: The aim of the present work was to characterize the electrophysiological effects of the non-steroidal anti-inflammatory drug diclofenac and to study the possible proarrhythmic potency of the drug in ventricular muscle. METHODS: Ion currents were recorded using voltage clamp technique in canine single ventricular cells and action potentials were obtained from canine ventricular preparations using microelectrodes. The proarrhythmic potency of the drug was investigated in an anaesthetized rabbit proarrhythmia model. RESULTS: Action potentials were slightly lengthened in ventricular muscle but were shortened in Purkinje fibers by diclofenac (20 µM. The maximum upstroke velocity was decreased in both preparations. Larger repolarization prolongation was observed when repolarization reserve was impaired by previous BaCl(2 application. Diclofenac (3 mg/kg did not prolong while dofetilide (25 µg/kg significantly lengthened the QT(c interval in anaesthetized rabbits. The addition of diclofenac following reduction of repolarization reserve by dofetilide further prolonged QT(c. Diclofenac alone did not induce Torsades de Pointes ventricular tachycardia (TdP while TdP incidence following dofetilide was 20%. However, the combination of diclofenac and dofetilide significantly increased TdP incidence (62%. In single ventricular cells diclofenac (30 µM decreased the amplitude of rapid (I(Kr and slow (I(Ks delayed rectifier currents thereby attenuating repolarization reserve. L-type calcium current (I(Ca was slightly diminished, but the transient outward (I(to and inward rectifier (I(K1 potassium currents were not influenced. CONCLUSIONS: Diclofenac at therapeutic concentrations and even at high dose does not prolong repolarization markedly and does not increase the risk of arrhythmia in normal heart. However, high dose diclofenac treatment may lengthen repolarization and enhance proarrhythmic risk in hearts with reduced repolarization reserve.

Human urotensin-II is an endothelium-dependent vasodilator in rat small arteries

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Bottrill, Fiona E; Douglas, Stephen A; Hiley, C Robin; White, Richard

2000-01-01

The possible role of the endothelium in modulating responses to human urotensin-II (U-II) was investigated using isolated segments of rat thoracic aorta, small mesenteric artery, left anterior descending coronary artery and basilar artery.Human U-II was a potent vasoconstrictor of endothelium-intact isolated rat thoracic aorta (EC50=3.5±1.1 nM, Rmax=103±10% of control contraction induced by 60 mM KCl and 1 μM noradrenaline). However the contractile response was not significantly altered by removal of the endothelium or inhibition of nitric oxide synthesis with L-NAME (100 μM). Human U-II did not cause relaxation of noradrenaline-precontracted, endothelium-intact rat aortae.Human U-II contracted endothelium-intact rat isolated left anterior descending coronary arteries (EC50=1.3±0.8 nM, Rmax=20.1±4.9% of control contraction induced by 10 μM 5-HT). The contractile response was significantly enhanced by removal of the endothelium (Rmax=55.4±16.1%). Moreover, human U-II caused concentration-dependent relaxation of 5-HT-precontracted arteries, which was abolished by L-NAME or removal of the endothelium.No contractile effects of human U-II were found in rat small mesenteric arteries. However the peptide caused potent, concentration- and endothelium-dependent relaxations of methoxamine-precontracted vessels. The relaxant responses were potentiated by L-NAME (300 μM) but abolished in the additional presence of 25 mM KCl (which inhibits the actions of endothelium-derived hyperpolarizing factor).The present study is the first to show that human U-II is a potent endothelium-dependent vasodilator in some rat resistance vessels, and acts through release of EDHF as well as nitric oxide. Our findings have also highlighted clear anatomical differences in the responses of different vascular beds to human U-II which are likely to be important in determining the overall cardiovascular activity of this peptide. PMID:10952676

Cell phone use diminishes self-awareness of the adverse effects of cell phone use on driving.

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2017-03-01

Multitasking may diminish the self-awareness of performance that is often essential for self-regulation : and self-knowledge. Participants in an experiment drove on a simulator while talking or not talking on a : cell phone. The errors they made whil...

Alterations of cerebral blood flow and cerebrovascular reserve in patients with chronic traumatic brain injury accompanying deteriorated intelligence

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Song, Ho Chun; Bom, Hee Seung [Chonnam National Univ. Hospital, Kwangju (Korea, Republic of)

2000-06-01

The purpose of this study was to evaluate alterations of regional cerbral blood flow (CBF) and cerebrovascular reserve (CVR), and correlation between these alternations and cognitive dysfunctin in patients with chronic traumatic brain injury (TBI) and normal brain MRI findings. Thirty TBI patients and 19 healthy volunteers underwent rest/acetazolaminde brain SPECT using Tc-99m HMPAO. Korean-Wechsler Adult Intelligence scale test was also performed in the patient group. Statistical analysis was performed with statistical parametric mapping software (SPM '97). CBF was diminished in the left hemisphere including Wernicke's area in all patients with lower verbal scale scores. In addition, a reduction in CBF in the right frontal, temporal and parietal cortices was related with depressed scores in information, digital span, arithmetic and similarities. In patients with lower performance scale scores, CBF was mainly diminished in the right hemisphere including superior temporal and supramarginal gyri, premotor, primary somatomotor and a part of prefrontal cortices, left frontal lobe and supramarginal gyrus. CVR was diminished in sixty-four Brodmann's areas compared to control. A reduction in CVR was demonstrated bilaterally in the frontal and temporal lobes in patients with lower scores in both verbal and performance tests, and in addition, both inferior parietal and occipital lobes in information subset. Alterations of CBF and CVR were demonstrated in the symptomatic TBI patients with normal MRI finding. These alterations were correlated with the change of intelligence, of which the complex functions are subserved by multiple interconnected cortical structures.

Preparation of 14c- amd 180-labeled 2-[2-methoxy-4-(methylsulfinyl)phenyl]-1H-imidazo[4,5-c]-pyridine hydrochloride (LY175326), a cardiotonic with inotropic and vasodilator activities

International Nuclear Information System (INIS)

Kau, Don; Krushinski, J.H.; Robertson, D.W.

1985-01-01

Two different forms of 14 C-labeled 2-methoxy-4-(methyl-thio)benzoic acid were prepared and employed in the synthesis of 14 C-labeled 2-:2-methoxy-4-(methylsulfinyl)phenyl:-1H-imidazo-[4,5-c]pyridine hydrochloride (LY175326), a cardiotonic with inotropic and vasodilator activities that is currently in clinical trials. The synthetic procedures described in this report allowed the introduction of the 14 C-label in the antepenultimate step. Additionally, an 18 0-labeled form of LY175326 was synthesized to facilitate kinetic analysis of the formation of its sulfide and sulfone metabolites. (author)

Less Guilty by Reason of Adolescence: Developmental Immaturity, Diminished Responsibility, and the Juvenile Death Penalty

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Steinberg, Laurence; Scott, Elizabeth S.

2003-01-01

The authors use a developmental perspective to examine questions about the criminal culpability of juveniles and the juvenile death penalty. Under principles of criminal law, culpability is mitigated when the actor's decision-making capacity is diminished, when the criminal act was coerced, or when the act was out of character. The authors argue…

Retigabine diminishes the effects of acetylcholine, adrenaline and adrenergic agonists on the spontaneous activity of guinea pig smooth muscle strips in vitro.

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Apostolova, Elisaveta; Zagorchev, Plamen; Kokova, Vesela; Peychev, Lyudmil

2017-03-01

The aim of this study is to evaluate the effect of retigabine on the smooth muscle response to acetylcholine, adrenaline, α-and β-adrenoceptor agonists. We studied the change in the spontaneous smooth muscle contraction of guinea pig gastric corpus strips before and after 20-min treatment with 2μM retigabine. We also evaluated the effect of retigabine on the smooth muscle response to 10μM acetylcholine, 1 and 10μM adrenaline, 1μM methoxamine, 0.1μM p-iodoclonidine and 10μM isoproterenol. We observed a significant reduction in the effects of all studied mediators and agonists when they were added to organ baths in the presence of retigabine. Retigabine diminished the effect of acetylcholine on the spontaneous smooth muscle activity. The effect was fully antagonized by XE-991 (Kv7 channel blocker), which supports our hypothesis about the role of KCNQ channels in the registered changes. The increase in the contraction force after adding of 1μM adrenaline, methoxamine, and 0.1μM p-iodoclonidine was also significantly smaller in presence of retigabine. However, comparing the effect of 10μM adrenaline on the contractility before and after treatment with retigabine, we observed increased contractility when retigabine was present in the organ baths. A possible explanation for the observed diminished effects of mediators and receptor agonists is that the effect of retigabine on smooth muscle contractility is complex. The membrane hyperpolarization, the interaction between Kv7 channels and adrenoceptors, and the influence on signaling pathways may contribute to the summary smooth muscle response. Copyright © 2016 Elsevier B.V. All rights reserved.

Discovery and Computational Rationalization of Diminishing Alternation in [n]Dendralenes.

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Saglam, Mehmet F; Fallon, Thomas; Paddon-Row, Michael N; Sherburn, Michael S

2016-01-27

The [n]dendralenes are a family of acyclic hydrocarbons which, by virtue of their ability to rapidly generate structural complexity, have attracted significant recent synthetic attention. [3]Dendralene through [8]dendralene have been previously prepared but no higher member of the family has been reported to date. Here, we describe the first chemical syntheses of the "higher" dendralenes, [9]dendralene through [12]dendralene. We also report a detailed investigation into the spectroscopic properties and chemical reactivity of the complete family of fundamental hydrocarbons, [3]dendralene to [12]dendralene. These studies reveal the first case of diminishing alternation in behavior in a series of related structures. We also report a comprehensive series of computational studies, which trace this dampening oscillatory effect in both spectroscopic measurements and chemical reactivity to conformational preferences.

Gesturing more diminishes recall of abstract words when gesture is allowed and concrete words when it is taboo.

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Matthews-Saugstad, Krista M; Raymakers, Erik P; Kelty-Stephen, Damian G

2017-07-01

Gesture during speech can promote or diminish recall for conversation content. We explored effects of cognitive load on this relationship, manipulating it at two scales: individual-word abstractness and social constraints to prohibit gestures. Prohibited gestures can diminish recall but more so for abstract-word recall. Insofar as movement planning adds to cognitive load, movement amplitude may moderate gesture effects on memory, with greater permitted- and prohibited-gesture movements reducing abstract-word recall and concrete-word recall, respectively. We tested these effects in a dyadic game in which 39 adult participants described words to confederates without naming the word or five related words. Results supported our expectations and indicated that memory effects of gesturing depend on social, cognitive, and motoric aspects of discourse.

Effect of ABO blood type on ovarian reserve in Chinese women.

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Lin, Shengli; Li, Rong; Chi, Hongbin; Huang, Shuo; Zhang, Hua; Zheng, Xiaoying; Liu, Ping; Qiao, Jie

2014-12-01

To explore the effect of ABO blood type on ovarian reserve in Chinese women. Retrospective analysis. University-affiliated IVF center. The retrospective analysis involved 35,479 women who underwent in vitro fertilization and embryo transfer (IVF-ET) cycles between 2006 and 2012. None. The association between ABO blood types and diminished ovarian reserve (DOR). Among 35,479 Chinese women, 11,395 (32.12%) had blood type B, 10,583 (29.83%) had blood type O, 9,861 (27.79%) had blood type A, and 3,640 (10.26%) had blood type AB. There was a statistically significantly higher percentage of blood type O among those with follicle-stimulating hormone (FSH) levels ≤10 IU/L compared with those with FSH levels >10 IU/L. Conversely, among the women with DOR, there was statistically significantly higher percentage of those with blood types B and AB. Blood type A was not associated with DOR occurrence. Multivariate logistic regression analysis showed that blood type O was statistically significantly less often associated with DOR occurrence, whereas the B antigen (blood type B or AB) was statistically significantly associated with an increased risk of DOR. Our results have shown that there is an association between ABO blood type and DOR occurrence in Chinese women. Women with blood type O were statistically significantly less likely to have DOR, whereas those with B antigen (blood type B or AB) were statistically significantly more likely to have DOR. Blood type A was not associated with ovarian reserve. Copyright © 2014. Published by Elsevier Inc.

Extreme cognitions are associated with diminished ability to use disconfirming evidence.

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Haigh, Matthew; Dodd, Alyson L

2017-03-01

An Integrative Cognitive Model of mood swings and bipolar disorder proposes that cognitive styles characterized by extreme self-referent appraisals of internal states (e.g., 'If I have a bad night's sleep it means that I am about to have a breakdown') interfere with mood regulation. The aim of this study is to determine whether strong endorsement of such appraisals is predicted by a diminished ability to access disconfirming counterexamples. We examined whether the ability to access two different categories of counterexample (known as Disabling Conditions and Alternative Causes) would predict endorsement of extreme appraisals (measured by the Hypomanic Attitudes and Positive Predictions Inventory; HAPPI) and mania risk (measured by the Hypomanic Personality Scale; HPS). A non-clinical sample of 150 students completed the HAPPI, the HPS and a conditional reasoning task that indexed the ability to access Disabling Conditions and Alternative Causes. Current mood was controlled for using the Internal States Scale. The ability to make use of disabling counterexamples during the reasoning task was inversely related with scores on the HAPPI (r = -.19, p referent appraisals to a greater extent. There was no association between the use of alternative cause counterexamples and the HAPPI, and no association between either measure of counterexample generation and the HPS. A diminished ability to use disconfirming evidence when reasoning about the world may reinforce problematic cognitive styles such as extreme, personalized appraisals of experience, which can interfere with mood regulation. Problematic cognitive styles such as extreme, personalized appraisals of experience may be reinforced by the inability to produce or access evidence that disconfirms these maladaptive beliefs. This reasoning bias may be associated with cognitive styles underlying psychopathology. There may be clinical utility in exploring the use of disabler generation in psychological interventions, to

Estimation of coronary flow reserve by sestamibi imaging in patients with mild hypertension and normal coronary arteries

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Storto, G.; Gallicchio, R.; Maddalena, F.; Pellegrino, T.; Petretta, M.; Fiumara, G.; Cuocolo, A.

2015-01-01

Patients with hypertension may exhibit abnormal vasodilator capacity during pharmacological vasodilatation. We assessed coronary flow reserve (CFR) by sestamibi imaging in hypertensive patients with normal coronary vessels. Twenty-five patients with untreated mild essential hypertension and normal coronary vessels and 10 control subjects underwent dipyridamole-rest Tc-99m sestamibi imaging. Myocardial blood flow (MBF) was estimated by measuring first transit counts in pulmonary artery and myocardial counts from tomograhic images. CFR was expressed as the ratio of stress to rest MBF. Coronary vascular resistances (CVR) were computed as the ratio between mean arterial pressure and MBF. Estimated MBF at rest was not different in patients and controls (1.11±0.59 vs. 1.14±0.28 counts/pixel/s; P=0.87). Conversely, stress MBF was lower in patients than in controls (1.55±0.47 vs. 2.68±0.53 counts/pixel/s; P<0.001). Thus, CFR was reduced in patients compared to controls (1.61±0.58 vs. 2.43±0.62; P<0.001). Rest and stress CVR values were higher in patients (P<0.001), while stress-induced changes in CVR were not different (P=0.08) between patients (-51%) and controls (-62%). In the overall study population, a significant relation between CFR and stress-induced changes in CVR was observed (r=-0.86; P<0.001). Sestamibi imaging may detect impaired coronary vascular function in response to dipyridamole in patients with untreated mild essential hypertension and normal coronary arteries. A mild increase in arterial blood pressure does not affect baseline MBF, but impairs coronary reserve due to the amplified resting coronary resistances.

Rehearsal Strategies Can Enlarge or Diminish the Spacing Effect: Pure versus Mixed Lists and Encoding Strategy

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Delaney, Peter F.; Verkoeijen, Peter P. J. L.

2009-01-01

Using 5 experiments, the authors explored the dependency of spacing effects on rehearsal patterns. Encouraging rehearsal borrowing produced opposing effects on mixed lists (containing both spaced and massed repetitions) and pure lists (containing only one or the other), magnifying spacing effects on mixed lists but diminishing spacing effects on…

Does too much work hamper innovation? Evidence for diminishing returns of work hours for patent grants

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Celbis, M.G.; Turkeli, S.

2014-01-01

This study suggests that individual time is an important factor that needs to be considered in innovation research. We define two types of time: work time and free time. We find that work time has a positive but diminishing effect on innovative output such that after a certain point the

Two Days' Sleep Debt Causes Mood Decline During Resting State Via Diminished Amygdala-Prefrontal Connectivity.

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Motomura, Yuki; Katsunuma, Ruri; Yoshimura, Michitaka; Mishima, Kazuo

2017-10-01

Sleep debt (SD) has been suggested to evoke emotional instability by diminishing the suppression of the amygdala by the medial prefrontal cortex (MPFC). Here, we investigated how short-term SD affects resting-state functional connectivity between the amygdala and MPFC, self-reported mood, and sleep parameters. Eighteen healthy adult men aged 29 ± 8.24 years participated in a 2-day sleep control session (SC; time in bed [TIB], 9 hours) and 2-day SD session (TIB, 3 hours). On day 2 of each session, resting-state functional magnetic resonance imaging was performed, followed immediately by measuring self-reported mood on the State-Trait Anxiety Inventory-State subscale (STAI-S). STAI-S score was significantly increased, and functional connectivity between the amygdala and MPFC was significantly decreased in SD compared with SC. Significant correlations were observed between reduced rapid eye movement (REM) sleep and reduced left amygdala-MPFC functional connectivity (FCL_amg-MPFC) and between reduced FCL_amg-MPFC and increased STAI-S score in SD compared with SC. These findings suggest that reduced MPFC functional connectivity of amygdala activity is involved in mood deterioration under SD, and that REM sleep reduction is involved in functional changes in the corresponding brain regions. Having adequate REM sleep may be important for mental health maintenance. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Do online reviews diminish physician authority? The case of cosmetic surgery in the U.S.

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Menon, Alka V

2017-05-01

This article analyzes the substance and perception of online physician reviews, which are qualitative and quantitative assessments of physicians written and shared by patients, in the case of U.S. cosmetic surgery. Like other cash-pay medical specialties, cosmetic surgery is elective and paid for largely out of pocket, with patients having latitude in their choice of surgeon. Drawing on qualitative data from interviews, observations of an American Society of Aesthetic Plastic Surgery professional meeting, and online reviews from the platforms RealSelf and Yelp, I identify two interdependent contributors to physician authority: reputation and expertise. I argue that surgeons see reviews overwhelmingly as a threat to their reputation, even as actual review content often positively reinforces physician expertise and enhances physician reputation. I show that most online reviews linked to interview participants are positive, according considerable deference to surgeons. Reviews add patients' embodied and consumer expertise as a circumscribed supplement to surgeons' technical expertise. Moreover, reviews change the doctor-patient relationship by putting it on display for a larger audience of prospective patients, enabling patients and review platforms to affect physician reputation. Surgeons report changing how they practice to establish and maintain their reputations. This research demonstrates how physician authority in medical consumerist contexts is a product of reputation as well as expertise. Consumerism changes the doctor-patient relationship and makes surgeons feel diminished authority by dint of their reputational vulnerability to online reviews. Copyright © 2017 Elsevier Ltd. All rights reserved.

Probing the implicit suicidal mind: does the Death/Suicide Implicit Association Test reveal a desire to die, or a diminished desire to live?

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Harrison, Dominique P; Stritzke, Werner G K; Fay, Nicolas; Ellison, T Mark; Hudaib, Abdul-Rahman

2014-09-01

Assessment of implicit self-associations with death relative to life, measured by a death/suicide implicit association test (d/s-IAT), has shown promise in the prediction of suicide risk. The current study examined whether the d/s-IAT reflects an individual's desire to die or a diminished desire to live and whether the predictive utility of implicit cognition is mediated by life-oriented beliefs. Four hundred eight undergraduate students (285 female; Mage = 20.36 years, SD = 4.72) participated. Participants completed the d/s-IAT and self-report measures assessing 6 indicators of suicide risk (suicide ideation frequency and intensity, depression, nonsuicidal self-harm thoughts frequency and intensity, and nonsuicidal self-harm attempts), as well as survival and coping beliefs and history of prior suicide attempts. The d/s-IAT significantly predicted 5 out of the 6 indicators of suicide risk above and beyond the strongest traditional indicator of risk, history of prior suicide attempts. However, the effect of the d/s-IAT on each of the risk indicators was mediated by individuals' survival and coping beliefs. Moreover, the distribution of d/s-IAT scores primarily reflected variability in self-associations with life. Implicit suicide-related cognition appears to reflect a gradual diminishing of the desire to live, rather than a desire to die. Contemporary theories of suicide and risk assessment protocols need to account for the dynamic relationship between both risk and life-oriented resilience factors, and intervention strategies aimed at enhancing engagement with life should be a routine part of suicide risk management. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Exercise reveals impairments in left ventricular systolic function in patients with metabolic syndrome.

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Fournier, Sara B; Reger, Brian L; Donley, David A; Bonner, Daniel E; Warden, Bradford E; Gharib, Wissam; Failinger, Conard F; Olfert, Melissa D; Frisbee, Jefferson C; Olfert, I Mark; Chantler, Paul D

2014-01-01

Metabolic syndrome (MetS) is the manifestation of a cluster of cardiovascular risk factors and is associated with a threefold increase in the risk of cardiovascular morbidity and mortality, which is suggested to be mediated, in part, by resting left ventricular (LV) systolic dysfunction. However, to what extent resting LV systolic function is impaired in MetS is controversial, and there are no data indicating whether LV systolic function is impaired during exercise. Accordingly, the objective of this study was to examine comprehensively the LV and arterial responses to exercise in individuals with MetS without diabetes and/or overt cardiovascular disease in comparison to a healthy control population. Cardiovascular function was characterized using Doppler echocardiography and gas exchange in individuals with MetS (n = 27) versus healthy control subjects (n = 20) at rest and during peak exercise. At rest, individuals with MetS displayed normal LV systolic function but reduced LV diastolic function compared with healthy control subjects. During peak exercise, individuals with MetS had impaired contractility, pump performance and vasodilator reserve capacity versus control subjects. A blunted contractile reserve response resulted in diminished arterial-ventricular coupling reserve and limited aerobic capacity in individuals with MetS versus control subjects. These findings are of clinical importance, because they provide insight into the pathophysiological changes in MetS that may predispose this population of individuals to an increased risk of cardiovascular morbidity and mortality.

Diminished Auditory Responses during NREM Sleep Correlate with the Hierarchy of Language Processing.

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Meytal Wilf

Full Text Available Natural sleep provides a powerful model system for studying the neuronal correlates of awareness and state changes in the human brain. To quantitatively map the nature of sleep-induced modulations in sensory responses we presented participants with auditory stimuli possessing different levels of linguistic complexity. Ten participants were scanned using functional magnetic resonance imaging (fMRI during the waking state and after falling asleep. Sleep staging was based on heart rate measures validated independently on 20 participants using concurrent EEG and heart rate measurements and the results were confirmed using permutation analysis. Participants were exposed to three types of auditory stimuli: scrambled sounds, meaningless word sentences and comprehensible sentences. During non-rapid eye movement (NREM sleep, we found diminishing brain activation along the hierarchy of language processing, more pronounced in higher processing regions. Specifically, the auditory thalamus showed similar activation levels during sleep and waking states, primary auditory cortex remained activated but showed a significant reduction in auditory responses during sleep, and the high order language-related representation in inferior frontal gyrus (IFG cortex showed a complete abolishment of responses during NREM sleep. In addition to an overall activation decrease in language processing regions in superior temporal gyrus and IFG, those areas manifested a loss of semantic selectivity during NREM sleep. Our results suggest that the decreased awareness to linguistic auditory stimuli during NREM sleep is linked to diminished activity in high order processing stations.

Diminished Auditory Responses during NREM Sleep Correlate with the Hierarchy of Language Processing.

Science.gov (United States)

Wilf, Meytal; Ramot, Michal; Furman-Haran, Edna; Arzi, Anat; Levkovitz, Yechiel; Malach, Rafael

2016-01-01

Natural sleep provides a powerful model system for studying the neuronal correlates of awareness and state changes in the human brain. To quantitatively map the nature of sleep-induced modulations in sensory responses we presented participants with auditory stimuli possessing different levels of linguistic complexity. Ten participants were scanned using functional magnetic resonance imaging (fMRI) during the waking state and after falling asleep. Sleep staging was based on heart rate measures validated independently on 20 participants using concurrent EEG and heart rate measurements and the results were confirmed using permutation analysis. Participants were exposed to three types of auditory stimuli: scrambled sounds, meaningless word sentences and comprehensible sentences. During non-rapid eye movement (NREM) sleep, we found diminishing brain activation along the hierarchy of language processing, more pronounced in higher processing regions. Specifically, the auditory thalamus showed similar activation levels during sleep and waking states, primary auditory cortex remained activated but showed a significant reduction in auditory responses during sleep, and the high order language-related representation in inferior frontal gyrus (IFG) cortex showed a complete abolishment of responses during NREM sleep. In addition to an overall activation decrease in language processing regions in superior temporal gyrus and IFG, those areas manifested a loss of semantic selectivity during NREM sleep. Our results suggest that the decreased awareness to linguistic auditory stimuli during NREM sleep is linked to diminished activity in high order processing stations.

Income and Self-Rated Mental Health: Diminished Returns for High Income Black Americans

Directory of Open Access Journals (Sweden)

Shervin Assari

2018-05-01

Full Text Available Background: The minorities’ diminished return theory suggests that socioeconomic position (SEP generates smaller health gains for racial/ethnic minorities compared to Whites. The current study was a Black–White comparison of the association between household income and self-rated mental health (SRMH. Methods: This cross-sectional study used data from the 2017 State of the State Survey (SOSS. With representative sampling, the SOSS generates results that are generalizable to the state of Michigan. This study included 881 adults, (n = 92 Black and (n = 782 White. The independent variable was household income. The dependent variable was SRMH, measured using a single item. Age, gender, and participation in the labor force were covariates. Race/ethnicity was the focal moderator. Logistic regression models were used for data analysis. Results: Overall, higher household income was associated with better SRMH, net of covariates. An interaction was found between race/ethnicity and household income on SRMH, suggesting a smaller, or nonexistent, protective effect for Blacks compared to Whites. In race/ethnicity-stratified models, higher household income was associated with better SRMH for Whites but not Blacks. Conclusion: Supporting the minorities’ diminished return theory, our study documents differential effects for income on SRHM for Blacks and Whites, where Whites but not Blacks appear to benefit from their income. Given this, researchers and policy makers are cautioned against making assumptions that racial groups benefit equally from similar economic resources.

Pregnancy causes diminished myogenic tone and outward hypotrophic remodeling of the cerebral vein of Galen.

Science.gov (United States)

van der Wijk, Anne-Eva; Schreurs, Malou P H; Cipolla, Marilyn J

2013-04-01

Pregnancy increases the risk of several complications associated with the cerebral veins, including thrombosis and hemorrhage. In contrast to the cerebral arteries and arterioles, few studies have focused on the effect of pregnancy on the cerebral venous side. Here, we investigated for the first time the effect of pregnancy on the function and structure of the cerebral vein of Galen in rats. Our major finding was that cerebral veins from late-pregnant (LP, n=11) rats had larger lumen diameters and thinner walls than veins from nonpregnant (NP, n=13) rats, indicating that pregnancy caused outward hypotrophic remodeling of the vein of Galen. Moreover, veins from NP animals had a small amount of myogenic tone at 10 mm Hg (3.9±1.0%) that was diminished in veins during pregnancy (0.8±0.3%; Ppregnancy. Using immunohistochemistry, we show that the vein of Galen receives perivascular innervation, and that serotonergic innervation of cerebral veins is significantly higher in veins from LP animals. Outward hypotrophic remodeling and diminished tone of cerebral veins during pregnancy may contribute to the development of venous pathology through elevated wall tension and wall stress, and possibly by promoting venous blood stasis.

Myocardial blood flow reserve is impaired in patients with aortic valve calcification and unobstructed epicardial coronary arteries.

Science.gov (United States)

Nel, Karen; Nam, Michael C Y; Anstey, Chris; Boos, Christopher J; Carlton, Edward; Senior, Roxy; Kaski, Juan Carlos; Khattab, Ahmed; Shamley, Delva; Byrne, Christopher D; Stanton, Tony; Greaves, Kim

2017-12-01

Although calcific aortic valve disease (CAVD) is associated with coronary atherosclerosis, it is not known whether early CAVD is associated with coronary microcirculatory dysfunction (CMD). We sought to investigate the relationship between myocardial blood flow reserve (MBFR) - a measure of CMD, and early CAVD in the absence of obstructive epicardial coronary artery disease. We also determined whether this relationship was independent of coronary artery disease (CAD) and hs-CRP, a marker of systemic inflammation. 183 patients with chest pain and unobstructed coronary arteries were studied. Aortic valve calcification score (AVCS), coronary total plaque length (TPL), and coronary calcium score were quantified from multislice CT. MBFR was assessed using vasodilator myocardial contrast echocardiography. Hs-CRP was measured from venous blood using a particle-enhanced immunoassay. Mean (±SD) participant age was 59.8 (9.6) years. Mean AVCS was 68 (258) AU, TPL was 15.6 (22.2) mm, and median coronary calcification score was 43.5AU. Mean MBFR was 2.20 (0.52). Mean hs-CRP was 2.52 (3.86) mg/l. Multivariable linear regression modelling incorporating demographics, coronary plaque characteristics, MBFR, and inflammatory markers, demonstrated that age (β=0.05, 95% CI: 0.02, 0.08, P=0.007), hs-CRP (β=0.09, CI: 0.02, 0.16, P=0.010) and diabetes (β=1.03, CI: 0.08, 1.98, P=0.033), were positively associated with AVCS. MBFR (β=-0.87, CI: -1.44, -0.30, P=0.003), BMI (β=-0.11, CI: -0.21, -0.01, P=0.033), and LDL (β=-0.32, CI: -0.61, -0.03, P=0.029) were negatively associated with AVCS. TPL and coronary calcium score were not independently associated with AVCS when included in the regression model. Coronary microvascular function as determined by measurement of myocardial blood flow reserve is independently associated with early CAVD. This effect is independent of the presence of coronary artery disease and also systemic inflammation. Copyright © 2017 Elsevier B.V. All rights

Deficiency of vasodilator-stimulated phosphoprotein (VASP increases blood-brain-barrier damage and edema formation after ischemic stroke in mice.

Directory of Open Access Journals (Sweden)

Peter Kraft

2010-12-01

Full Text Available Stroke-induced brain edema formation is a frequent cause of secondary infarct growth and deterioration of neurological function. The molecular mechanisms underlying edema formation after stroke are largely unknown. Vasodilator-stimulated phosphoprotein (VASP is an important regulator of actin dynamics and stabilizes endothelial barriers through interaction with cell-cell contacts and focal adhesion sites. Hypoxia has been shown to foster vascular leakage by downregulation of VASP in vitro but the significance of VASP for regulating vascular permeability in the hypoxic brain in vivo awaits clarification.Focal cerebral ischemia was induced in Vasp(-/- mice and wild-type (WT littermates by transient middle cerebral artery occlusion (tMCAO. Evan's Blue tracer was applied to visualize the extent of blood-brain-barrier (BBB damage. Brain edema formation and infarct volumes were calculated from 2,3,5-triphenyltetrazolium chloride (TTC-stained brain slices. Both mouse groups were carefully controlled for anatomical and physiological parameters relevant for edema formation and stroke outcome. BBB damage (p0.05 towards worse neurological outcomes.Our study identifies VASP as critical regulator of BBB maintenance during acute ischemic stroke. Therapeutic modulation of VASP or VASP-dependent signalling pathways could become a novel strategy to combat excessive edema formation in ischemic brain damage.

Noninvasive assessment of coronary stenoses by myocardial imaging during pharmacologic coronary vasodilation. VI. Detection of coronary artery disease in human beings with intravenous N-13 ammonia and positron computed tomography

International Nuclear Information System (INIS)

Schelbert, H.R.; Wisenberg, G.; Phelps, M.E.; Gould, K.L.; Henze, E.; Hoffman, E.J.; Gomes, A.; Kuhl, D.E.

1982-01-01

The possibility of detecting mild coronary stenoses with positron computed tomography and nitrogen (N-13) ammonia administered during pharmacologic coronary vasodilation was previously demonstrated in chronically instrumented dogs. The feasibility of using this technique in human beings and its sensitivity in determining the degree and extent of coronary artery disease were examined in 13 young normal healthy volunteers and 32 patients with angiographically documented coronary artery disease. N-13 ammonia was administered intravenously and its distribution in the left ventricular myocardium recorded at rest and during dipyridamole-induced coronary hyperemia. In the 13 volunteers, N-13 activity was homogeneous at rest and during hyperemia, whereas 31 of the 32 patients had regional defects on the hyperemic images not present during rest. All six patients with double, all 10 with triple and 15 of 16 patients with single vessel disease (97 percent) were correctly identified with the technique. Two vessel involvement was correctly identified in five of the six patients with double vessel disease and three vessel disease in six of 10 patients. Of all 58 coronary stenoses, 52 (90 percent) were correctly identified. In a subgroup of 11 patients, the technique was compared with exercise thallium-201 planar images, which were abnormal in 10 (91 percent) whereas N-13 images were abnormal in all 11. Of the 19 stenosed coronary arteries in this subgroup, 11 (58 percent) were correctly identified with thallium-201 and 17 (89 percent) with tomography (p less than 0.01). It is concluded that cross-sectional imaging of the myocardial distribution of N-13 ammonia administered during pharmacologic coronary vasodilation is a highly sensitive and accurate means for noninvasive detection of coronary stenoses in human beings and for estimating the extent of coronary artery disease

Overexpression of CRF in the BNST diminishes dysphoria but not anxiety-like behavior in nicotine withdrawing rats.

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Qi, Xiaoli; Guzhva, Lidia; Yang, Zhihui; Febo, Marcelo; Shan, Zhiying; Wang, Kevin K W; Bruijnzeel, Adriaan W

2016-09-01

Smoking cessation leads to dysphoria and anxiety, which both increase the risk for relapse. This negative affective state is partly mediated by an increase in activity in brain stress systems. Recent studies indicate that prolonged viral vector-mediated overexpression of stress peptides diminishes stress sensitivity. Here we investigated whether the overexpression of corticotropin-releasing factor (CRF) in the bed nucleus of the stria terminalis (BNST) diminishes nicotine withdrawal symptoms in rats. The effect of nicotine withdrawal on brain reward function was investigated with an intracranial self-stimulation (ICSS) procedure. Anxiety-like behavior was investigated in the elevated plus maze test and a large open field. An adeno-associated virus (AAV) pseudotype 2/5 vector was used to overexpress CRF in the lateral BNST and nicotine dependence was induced using minipumps. Administration of the nicotinic receptor antagonist mecamylamine and cessation of nicotine administration led to a dysphoria-like state, which was prevented by the overexpression of CRF in the BNST. Nicotine withdrawal also increased anxiety-like behavior in the elevated plus maze test and large open field test and slightly decreased locomotor activity in the open field. The overexpression of CRF in the BNST did not prevent the increase in anxiety-like behavior or decrease in locomotor activity. The overexpression of CRF increased CRF1 and CRF2 receptor gene expression and increased the CRF2/CRF1 receptor ratio. In conclusion, the overexpression of CRF in the BNST prevents the dysphoria-like state associated with nicotine withdrawal and increases the CRF2/CRF1 receptor ratio, which may diminish the negative effects of CRF on mood. Published by Elsevier B.V.

Mechanisms of diminished natural killer cell activity in pregnant women and neonates

International Nuclear Information System (INIS)

Baley, J.E.; Schacter, B.Z.

1985-01-01

Because alterations in natural killer (NK) activity in the perinatal period may be important in the maintenance of a healthy pregnancy, the mechanisms by which these alterations are mediated in neonates and in pregnant and postpartum women was examined. NK activity, as measured in a 4-hr 51 Cr-release assay and compared with adult controls, is significantly diminished in all three trimesters of pregnancy and in immediately postpartum women. In postpartum women, NK activity appears to be higher than in pregnant women, although this does not reach statistical significance. Pregnant and postpartum women have normal numbers of large granular lymphocytes and normal target cell binding in an agarose single cell assay but decreased lysis of the bound target cells. NK activity of mononuclear cells from postpartum women, in addition, demonstrate a shift in distribution to higher levels of resistance to gamma-irradiation. Further, sera from postpartum women cause a similar shift to increased radioresistance in mononuclear cells from adult controls. Because radioresistance is a property of interleukin 2-stimulated NK, the shift to radioresistance may represent lymphokine-mediated stimulation occurring during parturition. In contrast, cord blood cells have a more profound decrease in NK activity as determined by 51 Cr-release assay and decreases in both binding and lysis of bound target cells in the single cell assay. The resistance of NK activity in cord cells to gamma-irradiation is also increased, as seen in postpartum women. Cord blood serum, however, did not alter radioresistance or inhibit NK activity. The results suggest that the observed diminished NK activity in pregnant women and neonates arise by different mechanisms: an absence of mature NK cells in the neonate and an alteration of the NK cell in pregnancy leading to decreased killing

Poor sleep quality diminishes cognitive functioning independent of depression and anxiety in healthy young adults.

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Benitez, Andreana; Gunstad, John

2012-01-01

Sufficient sleep is essential for optimum cognitive and psychological functioning. Diminished sleep quality is associated with depression and anxiety, but the extent to which poor sleep quality uniquely impacts attention and executive functions independent of the effects of the common underlying features of depression and anxiety requires further exploration. Here 67 healthy young adults were given the Minnesota Multiphasic Personality Inventory, second edition (MMPI-2), the Pittsburgh Sleep Quality Index (PSQI), and tests of attention and executive functions. Similar to findings from a previous study with healthy community-based older adults (Nebes, Buysse, Halligan, Houck, & Monk, 2009), participants who reported poor sleep quality on the PSQI endorsed significantly greater scores on MMPI-2 Restructured Clinical scales related to depression and anxiety (Cohen's d = 0.77-1.05). In addition, PSQI component scores indexing poor sleep quality, duration, and medication use were associated with diminished attention and executive functions, even after controlling for emotional reactivity or demoralization (rs = 0.21-0.27). These results add to the concurrent validity of the PSQI, and provide further evidence for subtle cognitive decrements related to insufficient sleep even in healthy young adults. Future extension of these findings is necessary with larger samples and clinical comparison groups, and using objective indices of sleep dysfunction such as polysomnography.

Cyclooxygenase-2 Selectively Controls Renal Blood Flow Through a Novel PPARβ/δ-Dependent Vasodilator Pathway.

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Kirkby, Nicholas S; Sampaio, Walkyria; Etelvino, Gisele; Alves, Daniele T; Anders, Katie L; Temponi, Rafael; Shala, Fisnik; Nair, Anitha S; Ahmetaj-Shala, Blerina; Jiao, Jing; Herschman, Harvey R; Xiaomeng, Wang; Wahli, Walter; Santos, Robson A; Mitchell, Jane A

2018-02-01

Cyclooxygenase-2 (COX-2) is an inducible enzyme expressed in inflammation and cancer targeted by nonsteroidal anti-inflammatory drugs. COX-2 is also expressed constitutively in discreet locations where its inhibition drives gastrointestinal and cardiovascular/renal side effects. Constitutive COX-2 expression in the kidney regulates renal function and blood flow; however, the global relevance of the kidney versus other tissues to COX-2-dependent blood flow regulation is not known. Here, we used a microsphere deposition technique and pharmacological COX-2 inhibition to map the contribution of COX-2 to regional blood flow in mice and compared this to COX-2 expression patterns using luciferase reporter mice. Across all tissues studied, COX-2 inhibition altered blood flow predominantly in the kidney, with some effects also seen in the spleen, adipose, and testes. Of these sites, only the kidney displayed appreciable local COX-2 expression. As the main site where COX-2 regulates blood flow, we next analyzed the pathways involved in kidney vascular responses using a novel technique of video imaging small arteries in living tissue slices. We found that the protective effect of COX-2 on renal vascular function was associated with prostacyclin signaling through PPARβ/δ (peroxisome proliferator-activated receptor-β/δ). These data demonstrate the kidney as the principle site in the body where local COX-2 controls blood flow and identifies a previously unreported PPARβ/δ-mediated renal vasodilator pathway as the mechanism. These findings have direct relevance to the renal and cardiovascular side effects of drugs that inhibit COX-2, as well as the potential of the COX-2/prostacyclin/PPARβ/δ axis as a therapeutic target in renal disease. © 2018 The Authors.

Northern European trees show a progressively diminishing response to increasing atmospheric carbon dioxide concentrations

CSIR Research Space (South Africa)

Waterhouse, JS

2004-04-01

Full Text Available Reviews 23 (2004) 803?810 Northern European trees show a progressively diminishing response to increasing atmospheric carbon dioxide concentrations J.S. Waterhousea,*, V.R. Switsura,b, A.C. Barkera, A.H.C. Cartera,b,{, D.L. Hemmingc, N.J. Loaderd, I..., V.R., Waterhouse, J.S., Heaton, T.H.E., Carter, A.H.C., 1998. Climatic variation andthe stable carbon isotope composition of tree ring cellulose: an intercomparison of Quercus robur, Fagus sylvatica and Pinus silvestris. Tellus 50B, 25?33. J.ggi, M...

Thallium-201 myocardial imaging during pharmacologic coronary vasodilation: comparison of oral and intravenous administration of dipyridamole

International Nuclear Information System (INIS)

Taillefer, R.; Lette, J.; Phaneuf, D.C.; Leveille, J.; Lemire, F.; Essiambre, R.

1986-01-01

Although the diagnostic utility of thallium-201 myocardial imaging after dipyridamole infusion is well established, the intravenous form of the drug is not yet commercially available in North America. Fifty patients referred for coronary angiography were prospectively studied. Within a 2 week period, each patient underwent cardiac catheterization and thallium-201 myocardial imaging after both oral and intravenous dipyridamole administration. For the oral protocol, patients were randomly assigned to treatment with either 200 or 400 mg of dipyridamole in tablet form. Coronary artery stenoses of 70% or greater were considered significant. For the 25 patients who received a 200 mg oral dose of dipyridamole, the scintigraphic study showed perfusion defects in 65% of patients with significant coronary artery disease after the oral dose and in 85% of patients after the intravenous dose. For the 25 patients who received a 400 mg oral dose, the sensitivity of the scintigram was 84% after the oral dose and 79% after the intravenous dose. Except for headache and nausea, side effects were less severe and less frequent with oral (either 200 or 400 mg) than with intravenous dipyridamole. Because of the delayed and variable absorption of dipyridamole tablets, the oral studies required a longer period of medical supervision (45 to 60 minutes), and aminophylline was empirically administered after completion of the first set of thallium-201 images. It is concluded from this study that thallium-201 myocardial imaging after coronary vasodilation with a 400 mg oral dose of dipyridamole is a safe, widely available and reliable alternative for the evaluation of coronary artery disease in patients unable to achieve an adequate exercise level on stress testing

Cp/Heph mutant mice have iron-induced neurodegeneration diminished by deferiprone

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Zhao, Liangliang; Hadziahmetovic, Majda; Wang, Chenguang; Xu, Xueying; Song, Ying; Jinnah, H.A.; Wodzinska, Jolanta; Iacovelli, Jared; Wolkow, Natalie; Krajacic, Predrag; Weissberger, Alyssa Cwanger; Connelly, John; Spino, Michael; Lee, Michael K.; Connor, James; Giasson, Benoit; Harris, Z. Leah; Dunaief, Joshua L.

2016-01-01

Brain iron accumulates in several neurodegenerative diseases and can cause oxidative damage, but mechanisms of brain iron homeostasis are incompletely understood. Patients with mutations in the cellular iron-exporting ferroxidase ceruloplasmin (Cp) have brain iron accumulation causing neurodegeneration. Here, we assessed the brains of mice with combined mutation of Cp and its homolog hephaestin. Compared to single mutants, brain iron accumulation was accelerated in double mutants in the cerebellum, substantia nigra, and hippocampus. Iron accumulated within glia, while neurons were iron deficient. There was loss of both neurons and glia. Mice developed ataxia and tremor, and most died by 9 months. Treatment with the oral iron chelator deferiprone diminished brain iron levels, protected against neuron loss, and extended lifespan. Ferroxidases play important, partially overlapping roles in brain iron homeostasis by facilitating iron export from glia, making iron available to neurons. PMID:26303407

Diagnosis and management of persistent pulmonary hypertension of the newborn.

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Bendapudi, Perraju; Rao, Gopinath Gangadhara; Greenough, Anne

2015-06-01

Persistent pulmonary hypertension of new born (PPHN) is associated with mortality and morbidity; it may be idiopathic or secondary to a number of conditions. The mainstay of diagnosis and to exclude structural abnormalities is echocardiography. Brain type natriuretic peptide (BNP) levels are elevated in PPHN, but are insufficiently sensitive to contribute to routine diagnosis. Management includes improving oxygenation by optimising lung volume by ventilatory techniques and/or surfactant and administering pulmonary vasodilator agents. Inhaled nitric oxide (iNO), a selective pulmonary vasodilator, reduces the need for extracorporeal membrane oxygenation in term infants; it does not, however, improve mortality or have any long term positive effects in prematurely born infants or infants with congenital diaphragmatic hernia. Other pulmonary vasodilators have been reported in case series to be efficacious alone or in combination with iNO. Randomised trials with long term follow up are required to identify the optimum therapeutic strategies in PPHN. Copyright © 2015 Elsevier Ltd. All rights reserved.

Role of aminophylline in refractory heart failure: a comparison to the vasodilator sodium nitroprusside, the old and the new.

Science.gov (United States)

DiBianco, R; Rosenfeld, S P; Katz, R J; Simpson, A G; Fletcher, R D; Singh, S

1980-08-01

Aminophylline [(theophylline ethylene diamine (TED)] reportedly improved cardiac hemodynamics by lowering vascular resistances and increasing contractility. TED as used clinically has not been compared to the vasodilator sodium nitroprusside (NP). To assess the relative hemodynamic effects of these two commonly used agents, the following comparison was made. Ten patients with congestive cardiomyopathy in chronic refractory heart failure [New York Heart Association (NYHA) class IV] were studied. All patients demonstrated cardiomegaly by chest x ray and echocardiography (LVd = 6.3 +/- 0.7 cm) and markedly abnormal hemodynamics during baseline observations (see Table I). Hemodynamic measurements at baseline were compared after TED infusion (mean blood level = 16 +/- 12 micrograms/m/TED) and during intravenous NP. No significant changes in heart rate occurred during either therapeutic intervention; a fall in mean arterial pressure of 10 mmHg (p TED. Theophylline ethylene diamine demonstrated no detectable cardiac hemodynamic effects 60--90 min post infusion despite proven blood levels, whereas NP exhibited distinctly beneficial effects in this patient group. Previous studies demonstrating improved hemodynamics occurring with TED have been limited to the time of infusion or within the following 40 min, a time when TED blood levels are maximum and therefore closest to toxicity. The results of this study suggest that TED demonstrates no beneficial hemodynamic effects in refractory heart failure as early as 1 h after infusion despite blood levels in the therapeutic range.

Positive inotropic and vasodilator actions of milrinone in patients with severe congestive heart failure. Dose-response relationships and comparison to nitroprusside.

Science.gov (United States)

Jaski, B E; Fifer, M A; Wright, R F; Braunwald, E; Colucci, W S

1985-01-01

with nitroprusside for a matched reduction in mean aortic pressure or systemic vascular resistance, milrinone caused a significantly greater increase in stroke work index at the same or lower left ventricular end-diastolic pressure. Milrinone caused a concentration-related increase in dP/dt (32% increase at maximum milrinone dose), whereas nitroprusside had no effect. These data in patients with severe heart failure indicate that in addition to a vasodilating effect, milrinone exerts a concentration-related positive inotropic action that contributes significantly to the drug's overall hemodynamic effects. The positive inotropic action occurs at drug levels that do not exert significant chronotropic or vasodilator effects. Images PMID:3973022

Intrauterine Exposure to Paracetamol and Aniline Impairs Female Reproductive Development by Reducing Follicle Reserves and Fertility

DEFF Research Database (Denmark)

Holm, Jacob Bak; Mazaud-Guittot, Severine; Danneskiold-Samsøe, Niels Banhos

2016-01-01

in shortening of the anogenital distance in adult offspring, suggesting that fetal hormone signaling had been disturbed. Female offspring of paracetamol-exposed mothers had ovaries with diminished follicle reserve and reduced fertility. Fetal gonads of exposed animals had also reduced gonocyte numbers......, suggesting that the reduced follicle count in adults could be due to early disruption of germ cell development. However, ex vivo cultures of ovaries from 12.5 days post coitum fetuses showed no decrease in proliferation or expression following exposure to paracetamol. This suggests that the effect...... of paracetamol occurs prior to this developmental stage. Accordingly, using embryonic stem cells as a proxy for primordial germ cells we show that paracetamol is an inhibitor of cellular proliferation, but without cytotoxic effects. Collectively, our data show that intrauterine exposure to paracetamol at levels...

Inorganic nitrite and nitrate in cardiovascular therapy: A better alternative to organic nitrates as nitric oxide donors?

Science.gov (United States)

Münzel, Thomas; Daiber, Andreas

2018-03-01

In 1867 the organic nitrite, amyl nitrite, was introduced as a therapeutic agent in the treatment of angina pectoris and was later substituted by the organic nitrate nitroglycerin (NTG). Despite having a highly potent vasodilator capacity in veins>coronary arteries>arterioles, the vasodilator effects NTG are rapidly attenuated by the development of nitrate tolerance. We and others established that NTG treatment stimulates the production of reactive oxygen species such as superoxide and peroxynitrite with subsequent marked attenuation of the NTG vasodilator potency. The nitrite anion (NO 2 - ) has more recently been characterized to possess novel pharmacotherapeutic actions such as modulation of vasodilation under hypoxic conditions, thereby providing protection in ischemia-reperfusion injury. Administration of NO 2 - /NO 3 - has also been shown to improve myocardial function in heart failure and to lower blood pressure. Despite these positive aspects there is still a great need to study inorganic nitrate and nitrite therapy in various cardiovascular diseases in prospective outcome directed studies. In case being successful, this kind of therapy would indeed represent a cheap, therefore affordable, effective cardiovascular therapy without major side effects as observed in response to therapy with organic nitrates. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Autonomic Regulation of Splanchnic Circulation

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Kathleen A Fraser

1991-01-01

Full Text Available The role of the autonomic nervous system in circulatory regulation of the splanchnic organs (stomach, small intestine, colon, liver, pancreas and spleen is reviewed. In general, the sympathetic nervous system is primarily involved in vasoconstriction, while the parasympathetic contributes to vasodilation. Vasoconstriction in the splanchnic circulation appears to be mediated by alpha-2 receptors and vasodilation by activation of primary afferent nerves with subsequent release of vasodilatory peptides, or by stimulation of beta-adrenergic receptors. As well, an important function of the autonomic nervous system is to provide a mechanism by which splanchnic vascular reserve can be mobilized during stress to maintain overall cardiovascular homeostasis.

Diminished stress resistance and defective adaptive homeostasis in age-related diseases.

Science.gov (United States)

Lomeli, Naomi; Bota, Daniela A; Davies, Kelvin J A

2017-11-01

Adaptive homeostasis is defined as the transient expansion or contraction of the homeostatic range following exposure to subtoxic, non-damaging, signaling molecules or events, or the removal or cessation of such molecules or events ( Mol. Aspects Med. (2016) 49, 1-7 ). Adaptive homeostasis allows us to transiently adapt (and then de-adapt) to fluctuating levels of internal and external stressors. The ability to cope with transient changes in internal and external environmental stress, however, diminishes with age. Declining adaptive homeostasis may make older people more susceptible to many diseases. Chronic oxidative stress and defective protein homeostasis (proteostasis) are two major factors associated with the etiology of age-related disorders. In the present paper, we review the contribution of impaired responses to oxidative stress and defective adaptive homeostasis in the development of age-associated diseases. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

77 FR 21846 - Reserve Requirements of Depository Institutions: Reserves Simplification

Science.gov (United States)

2012-04-12

... Requirements of Depository Institutions: Reserves Simplification AGENCY: Board of Governors of the Federal Reserve System. ACTION: Final rule. SUMMARY: The Board is amending Regulation D, Reserve Requirements of Depository Institutions, to simplify the administration of reserve requirements. The final rule creates a...

Ambient groundwater flow diminishes nitrogen cycling in streams

Science.gov (United States)

Azizian, M.; Grant, S. B.; Rippy, M.; Detwiler, R. L.; Boano, F.; Cook, P. L. M.

2017-12-01

Modeling and experimental studies demonstrate that ambient groundwater reduces hyporheic exchange, but the implications of this observation for stream N-cycling is not yet clear. We utilized a simple process-based model (the Pumping and Streamline Segregation or PASS model) to evaluate N- cycling over two scales of hyporheic exchange (fluvial ripples and riffle-pool sequences), ten ambient groundwater and stream flow scenarios (five gaining and losing conditions and two stream discharges), and three biogeochemical settings (identified based on a principal component analysis of previously published measurements in streams throughout the United States). Model-data comparisons indicate that our model provides realistic estimates for direct denitrification of stream nitrate, but overpredicts nitrification and coupled nitrification-denitrification. Riffle-pool sequences are responsible for most of the N-processing, despite the fact that fluvial ripples generate 3-11 times more hyporheic exchange flux. Across all scenarios, hyporheic exchange flux and the Damkohler Number emerge as primary controls on stream N-cycling; the former regulates trafficking of nutrients and oxygen across the sediment-water interface, while the latter quantifies the relative rates of organic carbon mineralization and advective transport in streambed sediments. Vertical groundwater flux modulates both of these master variables in ways that tend to diminish stream N-cycling. Thus, anthropogenic perturbations of ambient groundwater flows (e.g., by urbanization, agricultural activities, groundwater mining, and/or climate change) may compromise some of the key ecosystem services provided by streams.

Diminishing Risk for Age-Related Macular Degeneration with Nutrition: A Current View

Directory of Open Access Journals (Sweden)

Allen Taylor

2013-07-01

Full Text Available Age-related macular degeneration (AMD is the leading cause of blindness in the elderly. Clinical hallmarks of AMD are observed in one third of the elderly in industrialized countries. Preventative interventions through dietary modification are attractive strategies, because they are more affordable than clinical therapies, do not require specialists for administration and many studies suggest a benefit of micro- and macro-nutrients with respect to AMD with few, if any, adverse effects. The goal of this review is to provide information from recent literature on the value of various nutrients, particularly omega-3 fatty acids, lower glycemic index diets and, perhaps, some carotenoids, with regard to diminishing risk for onset or progression of AMD. Results from the upcoming Age-Related Eye Disease Study (AREDS II intervention trial should be particularly informative.

Diminishing Risk for Age-Related Macular Degeneration with Nutrition: A Current View

Science.gov (United States)

Schleicher, Molly; Weikel, Karen; Garber, Caren; Taylor, Allen

2013-01-01

Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly. Clinical hallmarks of AMD are observed in one third of the elderly in industrialized countries. Preventative interventions through dietary modification are attractive strategies, because they are more affordable than clinical therapies, do not require specialists for administration and many studies suggest a benefit of micro- and macro-nutrients with respect to AMD with few, if any, adverse effects. The goal of this review is to provide information from recent literature on the value of various nutrients, particularly omega-3 fatty acids, lower glycemic index diets and, perhaps, some carotenoids, with regard to diminishing risk for onset or progression of AMD. Results from the upcoming Age-Related Eye Disease Study (AREDS) II intervention trial should be particularly informative. PMID:23820727

Measuring mental illness stigma with diminished social desirability effects.

Science.gov (United States)

Michaels, Patrick J; Corrigan, Patrick W

2013-06-01

For persons with mental illness, stigma diminishes employment and independent living opportunities as well as participation in psychiatric care. Public stigma interventions have sought to ameliorate these consequences. Evaluation of anti-stigma programs' impact is typically accomplished with self-report questionnaires. However, cultural mores encourage endorsement of answers that are socially preferred rather than one's true belief. This problem, social desirability, has been circumvented through development of faux knowledge tests (KTs) (i.e., Error-Choice Tests); written to assess prejudice. Our KT uses error-choice test methodology to assess stigmatizing attitudes. Test content was derived from review of typical KTs for façade reinforcement. Answer endorsement suggests bias or stigma; such determinations were based on the empirical literature. KT psychometrics were examined in samples of college students, community members and mental health providers and consumers. Test-retest reliability ranged from fair (0.50) to good (0.70). Construct validity analyses of public stigma indicated a positive relationship with the Attribution Questionnaire and inverse relationships with Self-Determination and Empowerment Scales. No significant relationships were observed with self-stigma measures (recovery, empowerment). This psychometric evaluation study suggests that a self-administered questionnaire may circumvent social desirability and have merit as a stigma measurement tool.

Diminishing self-disclosure to maintain security in partners' care.

Science.gov (United States)

Lemay, Edward P; Melville, Michael C

2014-01-01

Six studies demonstrate that perceivers' desire to bond with targets motivates perceivers to misconstrue their own self-disclosure in ways that maintain perceivers' security in targets' care and commitment. Perceivers who strongly valued relationships with targets reported high levels of global self-disclosure, consistent with many findings suggesting salutary effects of disclosure. However, these same perceivers reported low self-disclosure of needs and desires in hypothetical (Study 1) and actual (Study 2) situations characterized by targets' unresponsive behavior. Similarly, in daily report (Study 3) and behavioral observation (Study 4) studies, perceivers who valued relationships with targets perceived high levels of self-disclosure when targets were responsive, but they perceived low self-disclosure when targets were unresponsive, and these perceptions seemed partly illusory. In turn, these perceptions of low self-disclosure in situations characterized by partners' unresponsive behavior predicted decreased perceptions of diagnosticity of targets' behavior (Studies 1-3) and buffered the negative affective and interpersonal effects of unresponsive behavior (Study 4). Experimental manipulations (Studies 5 and 6) demonstrated the motivational nature of perceived self-disclosure. Collectively, the results suggest that a desire to bond with targets motivates perceivers to downplay the diagnosticity of targets' unresponsive behavior through diminishing their self-disclosure, in turn preserving perceivers' trust in targets' care and commitment.

Augmented hypoxic cerebral vasodilation in men during 5 days at 3,810 m altitude

DEFF Research Database (Denmark)

Jensen, J B; Sperling, B; Severinghaus, J W

1996-01-01

, at the lower PCO2 due to the logarithmic relationship of PCO2 to CSF pH. This change was not significant after correction to log PCO2. We conclude that the cerebral vascular response to acute isocapnic hypoxia may increase during acclimatization at high altitude. The mechanism is unknown but is presumably......The fractional increase in cerebral blood flow (CBF) velocity (VCBF) from the control value with 5-min steps of isocapnic hypoxia and hyperoxic hypercapnia was measured by transcranial Doppler in six sea-level native men before and during a 5-day sojourn at 3,810 m altitude to determine whether...... cerebral vasoreactivity to low arterial O2 saturation (SaO2) gradually increased [as does the hypoxic ventilatory response (HVR)] or diminished (adapted, in concert with known slow fall of CBF) at altitude. A control resting PCO2 value was chosen each day during preliminary hyperoxia to set ventilation...

Comparison of characteristics parameters in the evaluation of wall thickness diminishing in admiralty brass tubes of the steam condenser, tested by eddy currents

International Nuclear Information System (INIS)

Obrutsky, Alba E.; Mendez, Jorge A.; Acosta, Cesar D.; Scopelliti, Jose D.

1999-01-01

This work is aimed to appraise the measure of the wall thickness diminishing in the signals evaluation obtained in the inspection of steam condenser by eddy currents. In the analysis of the obtained signals were observed in the brass tubes a great quantity of internal defects whose signal indicates that there were diminishing of the wall thickness between 80% and 100%. With all this information and analyzing the data acquired, the tubes with more important indications were selected to make a more exhaustive study of the found defectology. As first test, it was measured the thickness of the worn tubes, comparing them with the original ones that are in stock. It was verified that the tubes separated for this study presented a 30% less thickness in comparison with the new tubes. A semiquantitative chemical test (EDAX) was made to verify if it was the same material. One of the extracted tubes (066 Y1) was reinspected in order to isolate the area with indications. Once this was performed, it was decided to cut the tube to make a visual inspection and to evaluate to what type of defect corresponds to the signals obtained. In the metallography it was confirm that it was a horseshoe type defect. When performing a dimensional control test of the found real defect, it was checked that the information obtained by eddy currents regarding the diminishing of the wall thickness diminishing was valid. At a last stage of the test, it was proceed to make an study and verification of the used parameters, probes, standards and finally determine which shall be the convenient modifications to minimize errors. (author)

Finger cold-induced vasodilation of older Korean female divers, haenyeo: effects of chronic cold exposure and aging

Science.gov (United States)

Lee, Joo-Young; Park, Joonhee; Koh, Eunsook; Cha, Seongwon

2017-07-01

The aim of the present study was to evaluate the local cold tolerance of older Korean female divers, haenyeo ( N = 22) in terms of cold acclimatization and ageing. As control groups, older non-diving females ( N = 25) and young females from a rural area ( N = 15) and an urban area ( N = 51) participated in this study. To evaluate local cold tolerance, finger cold-induced vasodilation (CIVD) during finger immersion of 4 °C water was examined. As a result, older haenyeos showed greater minimum finger temperature and recovery finger temperature than older non-diving females ( P < 0.05), but similar responses in onset time, peak time, maximum finger temperature, frequency of CIVD, heart rate, blood pressure, and thermal and pain sensations as those of older non-diving females. Another novel finding was that young urban females showed more vulnerable responses to local cold in CIVD variables and subjective sensations when compared to older females, whereas young rural females had the most excellent cold tolerance in terms of maximum temperature and frequency of CIVD among the four groups ( P < 0.05). The present results imply that older haenyeos still retain cold acclimatized features on the periphery even though they changed their cotton diving suits to wet suits in the early 1980s. However, cardiovascular responses and subjective sensations to cold reflect aging effects. In addition, we suggest that young people who have been adapted to highly insulated clothing and indoor heating systems in winter should be distinguished from young people who were exposed to less modern conveniences when compared to the aged in terms of cold tolerance.

Quantitative thallium-201 single-photon emission computed tomography during maximal pharmacologic coronary vasodilation with adenosine for assessing coronary artery disease

International Nuclear Information System (INIS)

Nishimura, S.; Mahmarian, J.J.; Boyce, T.M.; Verani, M.S.

1991-01-01

The diagnostic value of maximal pharmacologic coronary vasodilation with intravenously administered adenosine in conjunction with thallium-201 single-photon emission computed tomography (SPECT) for detection of coronary artery disease was investigated in 101 consecutive patients who had concomitant coronary arteriography. Tomographic images were assessed visually and from computer-quantified polar maps of the thallium-201 distribution. Significant coronary artery disease, defined as greater than 50% luminal diameter stenosis, was present in 70 patients. The sensitivity for detecting patients with coronary artery disease using quantitative analysis was 87% in the total group, 82% in patients without myocardial infarction and 96% in those with prior myocardial infarction; the specificity was 90%. The sensitivity for diagnosing coronary artery disease in patients without infarction with single-, double-and triple-vessel disease was 76%, 86% and 90%, respectively. All individual stenoses were identified in 68% of patients with double-vessel disease and in 65% of those with triple-vessel disease. The extent of the perfusion defects, as quantified by polar maps, was directly related to the extent of coronary artery disease. In conclusion, quantitative thallium-201 SPECT during adenosine infusion has high sensitivity and specificity for diagnosing the presence of coronary artery disease, localizing the anatomic site of coronary stenosis and identifying the majority of affected vascular regions in patients with multivessel involvement

Efecto vasodilatador mediado por óxido nítrico del extracto hidroalcohólico de Zea mays L. (maíz morado en anillos aórticos de rata Vasodilator effect mediated by nitric oxide of the Zea mays L (andean purple corn hydroalcoholic extract in aortic rings of rat

Directory of Open Access Journals (Sweden)

Oscar Moreno-Loaiza

2010-12-01

Full Text Available Objetivo. Evaluar la respuesta vasodilatadora e inhibidora de la vasoconstricción del extracto hidroalcohólico de Zea mays L. (maíz morado y determinar si esta respuesta es mediada por óxido nítrico (NO. Materiales y métodos. Se obtuvo un extracto de las corontas de maíz morado maceradas durante ocho días en etanol al 70%, y posterior concentración del producto. Se trabajó con anillos aórticos de rata en cámara de órganos aislados, bañada con solución Krebs-Hensleit (K-H y se registró la actividad vasomotora con un transductor de tensión isométrica. Se produjo una contracción basal con KCl 120 mM sobre la cual determinó el efecto vasodilatador de tres dosis del extracto: 0,1; 0,5 y 1,0 mg/mL. Se utilizó L-NG-Nitroarginina metil ester (L-NAME para comprobar que la vasodilatación depende de la óxido nítrico sinteasa (NOs. Luego se comparó la inhibición de la contracción vascular tras la incubación durante 30 minutos, con extracto de maíz morado y captopril 10-5 M. Resultados. Se observó una reducción de la contracción máxima (100% a 85,25 ± 2,60%, 77,76 ± 3,23% y 73,3 ± 4,87%, para las dosis de 0,1; 0,5 y 1,0 mg/mL, respectivamente. La vasodilatación fue inhibida por la incubación previa con L-NAME. El extracto de maíz morado no inhibió la contracción vascular, a diferencia del captopril (reducción a 75,27 ± 8,61%. Conclusión. El extracto hidroalcohólico de Zea mays L produce vasodilatación dependiente de la síntesis de NO.Objective: To evaluate the vasodilator response of the hydroalcoholic extract of Zea mays L. (Andean purple corn and to determine if this response is mediated by nitric oxide (NO. Material and methods: We obtained an extract by maceration for eight days of Andean purple corn cobs in 70% ethanol and subsequent concentration of the product. Thoracic aortic rings were evaluated in an isolated organ chamber, bathed with Krebs-Hensleit solution (KH, and vasomotor activity was recorded

Nitric oxide, cholesterol oxides and endothelium-dependent vasodilation in plasma of patients with essential hypertension

Directory of Open Access Journals (Sweden)

P. Moriel

2002-11-01

Full Text Available The objective of the present study was to identify disturbances of nitric oxide radical (·NO metabolism and the formation of cholesterol oxidation products in human essential hypertension. The concentrations of·NO derivatives (nitrite, nitrate, S-nitrosothiols and nitrotyrosine, water and lipid-soluble antioxidants and cholesterol oxides were measured in plasma of 11 patients with mild essential hypertension (H: 57.8 ± 9.7 years; blood pressure, 148.3 ± 24.8/90.8 ± 10.2 mmHg and in 11 healthy subjects (N: 48.4 ± 7.0 years; blood pressure, 119.4 ± 9.4/75.0 ± 8.0 mmHg.Nitrite, nitrate and S-nitrosothiols were measured by chemiluminescence and nitrotyrosine was determined by ELISA. Antioxidants were determined by reverse-phase HPLC and cholesterol oxides by gas chromatography. Hypertensive patients had reduced endothelium-dependent vasodilation in response to reactive hyperemia (H: 9.3 and N: 15.1% increase of diameter 90 s after hyperemia, and lower levels of ascorbate (H: 29.2 ± 26.0, N: 54.2 ± 24.9 µM, urate (H: 108.5 ± 18.9, N: 156.4 ± 26.3 µM, ß-carotene (H: 1.1 ± 0.8, N: 2.5 ± 1.2 nmol/mg cholesterol, and lycopene (H: 0.4 ± 0.2, N: 0.7 ± 0.2 nmol/mg cholesterol, in plasma, compared to normotensive subjects. The content of 7-ketocholesterol, 5alpha-cholestane-3ß,5,6ß-triol and 5,6alpha-epoxy-5alpha-cholestan-3alpha-ol in LDL, and the concentration of endothelin-1 (H: 0.9 ± 0.2, N: 0.7 ± 0.1 ng/ml in plasma were increased in hypertensive patients. No differences were found for ·NO derivatives between groups. These data suggest that an increase in cholesterol oxidation is associated with endothelium dysfunction in essential hypertension and oxidative stress, although ·NO metabolite levels in plasma are not modified in the presence of elevated cholesterol oxides.

Status of fossil fuel reserves; Etat des reserves des combustibles fossiles

Energy Technology Data Exchange (ETDEWEB)

Laherrere, J

2005-07-01

Reserves represent the sum of past and future productions up to the end of production. In most countries the reserve data of fields are confidential. Therefore, fossil fuel reserves are badly known because the published data are more political than technical and many countries make a confusion between resources and reserves. The cumulated production of fossil fuels represents only between a third and a fifth of the ultimate reserves. The production peak will take place between 2020 and 2050. In the ultimate reserves, which extrapolate the past, the fossil fuels represent three thirds of the overall energy. This document analyses the uncertainties linked with fossil fuel reserves: reliability of published data, modeling of future production, comparison with other energy sources, energy consumption forecasts, reserves/production ratio, exploitation of non-conventional hydrocarbons (tar sands, extra-heavy oils, bituminous shales, coal gas, gas shales, methane in overpressure aquifers, methane hydrates), technology impacts, prices impact, and reserves growth. (J.S.)

77 FR 66361 - Reserve Requirements of Depository Institutions: Reserves Simplification

Science.gov (United States)

2012-11-05

... Requirements of Depository Institutions: Reserves Simplification AGENCY: Board of Governors of the Federal... (Reserve Requirements of Depository Institutions) published in the Federal Register on April 12, 2012. The... simplifications related to the administration of reserve requirements: 1. Create a common two-week maintenance...

Foreign Exchange Reserves and the Reserve Bank’s Balance Sheet

OpenAIRE

Christian Vallence

2012-01-01

The Reserve Bank of Australia holds and manages the nation’s foreign exchange reserve assets in order to meet its policy objectives. While Australia’s foreign exchange reserves are relatively modest by international standards, they nonetheless constitute a sizeable portion of the Bank’s balance sheet, and variations in the Australian dollar value of these reserves are usually the most volatile component of the Bank’s profit and loss statement. This article discusses some of the key decisions ...

COMBATING CYBERBULLYING AS STRATEGY TO DIMINISH THE STUDENTS’ AGGRESSIVENESS

Directory of Open Access Journals (Sweden)

Ali ABU RIA

2018-03-01

Full Text Available This article addresses the relationship between cyberbullying and students’ behaviors. At present, cyber security is one of the most discussed topics in most countries of the world. Cyber space is characterized by lack of borders, dynamism and anonymity, generating both opportunities for the development of the information society and risks to its functioning and its beneficiaries. Noting the noxious impact of cyberbullying on youth behaviors, we propose tackling cyberbullying as a strategy to diminish students' aggressiveness in the school.COMBATEREA BULLYING-ULUI CIBERNETIC CA STRATEGIE DE DIMINUARE A AGRESIVITĂȚII ELEVILORÎn articol este abordată relația dintre bullying-ul cibernetic și comportamentele elevilor. La etapa actuală, securitatea cibernetică este unul dintre cele mai discutate subiecte în majoritatea țărilor lumii. Spaţiul cibernetic se caracterizează prin lipsa frontierelor, dinamism şi anonimat, generând atât oportunităţi de dezvoltare a societăţii informaţionale, cât şi riscuri la adresa funcţionării acesteia și a beneficiarilor săi. Constatând impactul nociv al bullying-ului cibernetic asupra comportamentelor tinerilor, propunem abordarea combaterii bullying-ului cibernetic ca strategie de diminuare a agresi­vității elevilor în școală.

Mycobacterium tuberculosis has diminished capacity to counteract redox stress induced by elevated levels of endogenous superoxide.

Science.gov (United States)

Tyagi, Priyanka; Dharmaraja, Allimuthu T; Bhaskar, Ashima; Chakrapani, Harinath; Singh, Amit

2015-07-01

Mycobacterium tuberculosis (Mtb) has evolved protective and detoxification mechanisms to maintain cytoplasmic redox balance in response to exogenous oxidative stress encountered inside host phagocytes. In contrast, little is known about the dynamic response of this pathogen to endogenous oxidative stress generated within Mtb. Using a noninvasive and specific biosensor of cytoplasmic redox state of Mtb, we for first time discovered a surprisingly high sensitivity of this pathogen to perturbation in redox homeostasis induced by elevated endogenous reactive oxygen species (ROS). We synthesized a series of hydroquinone-based small molecule ROS generators and found that ATD-3169 permeated mycobacteria to reliably enhance endogenous ROS including superoxide radicals. When Mtb strains including multidrug-resistant (MDR) and extensively drug-resistant (XDR) patient isolates were exposed to this compound, a dose-dependent, long-lasting, and irreversible oxidative shift in intramycobacterial redox potential was detected. Dynamic redox potential measurements revealed that Mtb had diminished capacity to restore cytoplasmic redox balance in comparison with Mycobacterium smegmatis (Msm), a fast growing nonpathogenic mycobacterial species. Accordingly, Mtb strains were extremely susceptible to inhibition by ATD-3169 but not Msm, suggesting a functional linkage between dynamic redox changes and survival. Microarray analysis showed major realignment of pathways involved in redox homeostasis, central metabolism, DNA repair, and cell wall lipid biosynthesis in response to ATD-3169, all consistent with enhanced endogenous ROS contributing to lethality induced by this compound. This work provides empirical evidence that the cytoplasmic redox poise of Mtb is uniquely sensitive to manipulation in steady-state endogenous ROS levels, thus revealing the importance of targeting intramycobacterial redox metabolism for controlling TB infection. Copyright © 2015 The Authors. Published by

Clonidine, an alpha2-receptor agonist, diminishes GABAergic neurotransmission to cardiac vagal neurons in the nucleus ambiguus.

Science.gov (United States)

Philbin, Kerry E; Bateman, Ryan J; Mendelowitz, David

2010-08-06

In hypertension, there is an autonomic imbalance in which sympathetic activity dominates over parasympathetic control. Parasympathetic activity to the heart originates from cardiac vagal neurons located in the nucleus ambiguus. Presympathetic neurons that project to sympathetic neurons in the spinal cord are located in the ventral brainstem in close proximity to cardiac vagal neurons, and many of these presympathetic neurons are catecholaminergic. In addition to their projection to the spinal cord, many of these presympathetic neurons have axon collaterals that arborize into neighboring cardiorespiratory locations and likely release norepinephrine onto nearby neurons. Activation of alpha(2)-adrenergic receptors in the central nervous system evokes a diverse range of physiological effects, including reducing blood pressure. This study tests whether clonidine, an alpha(2)-adrenergic receptor agonist, alters excitatory glutamatergic, and/or inhibitory GABAergic or glycinergic synaptic neurotransmission to cardiac vagal neurons in the nucleus ambiguus. Cardiac vagal neurons were identified in an in vitro brainstem slice preparation, and synaptic events were recording using whole cell voltage clamp methodologies. Clonidine significantly inhibited GABAergic neurotransmission but had no effect on glycinergic or glutamatergic pathways to cardiac vagal neurons. This diminished inhibitory GABAergic neurotransmission to cardiac vagal neurons would increase parasympathetic activity to the heart, decreasing heart rate and blood pressure. The results presented here provide a cellular substrate for the clinical use of clonidine as a treatment for hypertension as well as a role in alleviating posttraumatic stress disorder by evoking an increase in parasympathetic cardiac vagal activity, and a decrease in heart rate and blood pressure. Copyright 2010 Elsevier B.V. All rights reserved.

Female Offspring From Chronic Hyperandrogenemic Dams Exhibit Delayed Puberty and Impaired Ovarian Reserve.

Science.gov (United States)

Wang, Zhiqiang; Shen, Mingjie; Xue, Ping; DiVall, Sara A; Segars, James; Wu, Sheng

2018-02-01

Female offspring of many species exposed to high doses of androgens in utero experience endocrine dysfunction during adulthood. The phenotype of offspring from females with prepregnancy hyperandrogenemia and impaired ovulation, however, has not been examined. We developed a mouse model of hyperandrogenemia by implanting a low-dose dihydrotestosterone (DHT) pellet 15 days before conception. Female offspring born to dams with hyperandrogenemia (DHT daughters) had delayed puberty (P DHT (non-DHT daughters, PND37.5). Serum follicle-stimulating hormone (FSH) levels in the DHT daughters were fourfold higher (P DHT daughters (controls). DHT daughters showed an extended time in metestrus/diestrus and a shorter time in the proestrus/estrus phase compared with non-DHT daughters (P DHT daughters compared with non-DHT daughters (P DHT daughters compared with non-DHT daughters. Daughters from hyperandrogenemic females exhibited elevated prepubertal FSH levels, diminished ovarian response to superovulation, impaired estrous cyclicity, delayed onset of puberty, and reduced ovarian reserve, suggesting that fetal androgen exposure had lasting effects on female reproductive function. Copyright © 2018 Endocrine Society.

Replacing reserve requirements

OpenAIRE

Edward J. Stevens

1993-01-01

An examination of the fading significance of the Federal Reserve System's reserve requirements and the recent flowering of required clearing balances, a rapidly growing feature of Reserve Bank operations.

Pollutant tracking for 3 Western North Atlantic sea grasses by remote sensing: Preliminary diminishing white light responses of Thalassia testudinum, Halodule wrightii, and Zostera marina

International Nuclear Information System (INIS)

Thorhaug, Anitra; Berlyn, Graeme P.; Poulos, Helen M.; Goodale, Uromi M.

2015-01-01

Highlights: • Sea grass accessory pigments are more important than Chl at medium to low light intensity. • Partial absorption changes in Thalassia and also in Halodule at low intensity visible light ranges. • NDVI and chlNDI do not detect these changes or low light responses of sea grasses. • Intertidal sea grasses are less stressed than the subtidal species at low and high light. • Chl b is an important photosynthetic pigment in tropical/subtropical species. - Abstract: Sea grasses are foundation species for estuarine ecosystems. The available light for sea grasses diminishes rapidly during pollutant spills, effluent releases, disturbances such as intense riverine input, and tidal changes. We studied how sea grasses’ remote-sensing signatures and light-capturing ability respond to short term light alterations. In vivo responses were measured over the entire visible-light spectra to diminishing white-light on whole-living-plants’ spectral reflectance, including 6 h of full oceanic-light fluences from 10% to 100%. We analyzed differences by various reflectance indices. We compared the sea grasses species responses of tropical vs. temperate and intertidals (Halodule wrightii, and Zostera marina) vs. subtidal (Thalassia testudinum). Reflectance diminished with decreasing light intensity that coincided with greater accessory pigment stimulation (anthocyanin, carotenoids, xanthins). Chlorophyll a and Chlorophyll b differed significantly among species (Thalassia vs. Halodule). Photosynthetic efficiency diminished at high light intensities. The NDVI index was inadequate to perceive these differences. Our results demonstrate the leaf-level utility of data to remote sensing for mapping sea grass and sea grass stress

Metabolic Evidence of Diminished Lipid Oxidation in Women With Polycystic Ovary Syndrome

Science.gov (United States)

Whigham, Leah D.; Butz, Daniel E.; Dashti, Hesam; Tonelli, Marco; Johnson, LuAnn K.; Cook, Mark E.; Porter, Warren P.; Eghbalnia, Hamid R.; Markley, John L.; Lindheim, Steven R.; Schoeller, Dale A.; Abbott, David H.; Assadi-Porter, Fariba M.

2014-01-01

Polycystic ovary syndrome (PCOS), a common female endocrinopathy, is a complex metabolic syndrome of enhanced weight gain. The goal of this pilot study was to evaluate metabolic differences between normal (n=10) and PCOS (n=10) women via breath carbon isotope ratio, urinary nitrogen and nuclear magnetic resonance (NMR)-determined serum metabolites. Breath carbon stable isotopes measured by cavity ring down spectroscopy (CRDS) indicated diminished (pglucose tolerance test showed that a transient elevation in blood glucose levels decreased circulating levels of lipid, glucose and amino acid metabolic intermediates (acetone, 2-oxocaporate, 2-aminobutyrate, pyruvate, formate, and sarcosine) in PCOS women, whereas the 2 h glucose challenge led to increases in the same intermediates in normal women. These pilot data suggest that PCOS-related inflexibility in fasting-related switching between lipid and carbohydrate/protein utilization for carbon metabolism may contribute to enhanced weight gain. PMID:24765590

Diminished Economic Return of Socioeconomic Status at Birth among Black than White Youth

Directory of Open Access Journals (Sweden)

Shervin Assari

2018-05-01

Full Text Available Background: According to the Minorities’ Diminished Return theory, socioeconomic status (SES systemically generates larger gains for Whites compared to Blacks. It is, however, unknown whether the effects of baseline SES on future family income also varies between Blacks and Whites. Aims: Using a national sample, this study investigated racial variation in the effects of family SES (i.e., family structure, maternal education, and income at birth on subsequent household income at age 15. Methods: This 15-year longitudinal study used data from the Fragile Families and Child Wellbeing Study (FFCWS, which followed 1471 non-Hispanic Black or White families from the time of birth of their child for 15 years. Two family SES indicators (maternal education and income at birth were the independent variables. Family income 15 years later was the outcome. Maternal age, child gender, and family structure at baseline were covariates. Race was the focal moderator. Linear regression models were used for data analysis. Results: In the pooled sample, maternal education (b = 11.62, p < 0.001 and household income (b = 0.73, p < 0.001 at baseline were predictive of family income 15 years later. Race, however, interacted with maternal education (b = −12,073.89, p < 0.001 and household income (b = −312.47, p < 0.001 at birth on household income 15 years later, indicating smaller effects for Black compared to White families. These differential gains were independent of family structure, mother age, and child gender. Conclusions: The economic return of family SES is smaller for Black compared to White families, regardless of the SES indicator. Policies should specifically address structural barriers in the lives of racial and ethnic minorities to minimize the diminished return of SES resources across racial minority groups. Policies should also reduce extra cost of upward social mobility for racial minorities. As the likely causes are multi-level, solutions should

CAN MELATONIN BE EFFECTIVELY USED TO DIMINISH SIDE EFFECTS OF VARIOUS PSYCHOTROPIC DRUGS AND ELECTROCONVULSIVE THERAPY?

Directory of Open Access Journals (Sweden)

Roman Aleksandrovich Bekker

2017-10-01

Full Text Available Purpose. To study and summarize the existing evidence base for the use of melatonin as a mean to counteract or diminish the side effects of various psychotropic drugs and electroconvulsive therapy, and to provide the reader with relevant conclusions. Methodology. The authors have searched for the scientific literature regarding the use of melatonin as a mean to counteract or diminish the side effects of various psychotropic drugs and electroconvulsive therapy, using the PubMed and Google Scholar as a search tool. Then the authors thoroughly reviewed the data they found. The resulting review is presented in this article. Results. The data we have obtained from this review of the literature indicate that melatonin can be effectively used both in monotherapy and in combination with other therapeutic means in order to reduce several different side effects of psychotropic drugs and electroconvulsive therapy. Melatonin also deserves further study in this regard. The evidence base for its use in this manner is very variable in quality for different side effects. For now, the greatest evidence base exists regarding the potential effectiveness of melatonin in the prevention and treatment of drug-induced insomnia, memory and cognitive impairment, akathisia, tardive dyskinesias, and metabolic syndrome. Practical implications. The results we have obtained can be widely applied in psychiatry, neurology and addiction medicine, as well as in all those areas of general medicine, which make use of psychotropic drugs.

Nitroglycerin-mediated, but not flow-mediated vasodilation, is associated with blunted nocturnal blood pressure fall in patients with resistant hypertension.

Science.gov (United States)

Fontes-Guerra, Priscila C A; Cardoso, Claudia R L; Muxfeldt, Elizabeth S; Salles, Gil F

2015-08-01

Endothelial function by flow-mediated (FMD) and nitroglycerin-mediated vasodilations (NMD) was scarcely investigated in resistant hypertension. We aimed to assess the independent correlates of FMD and NMD in resistant hypertensive patients, particularly their associations with ambulatory blood pressures (BP) and nocturnal BP fall patterns. In a cross-sectional study, 280 resistant hypertensive patients performed 24-h ambulatory BP monitoring, carotid-femoral pulse wave velocity, polysomnography, and brachial artery FMD and NMD by high-resolution ultrasonography. Independent correlates of FMD, NMD, and brachial artery diameter (BAD) were assessed by multiple linear and logistic regressions. Median (interquartile range) FMD was 0.75% (-0.6 to +4.4%) and NMD was 11.8% (7.1-18.4%). Baseline BAD and diabetes were independently associated with both FMD and NMD. Older age and prior cardiovascular diseases were associated with altered FMD, whereas higher night-time SBP and lower nocturnal SBP fall were associated with impaired NMD. Moreover, there was a significant gradient of impaired NMD according to blunted nocturnal BP decline patterns. BAD was independently associated with age, sex, BMI, albuminuria, and nocturnal SBP fall. Further adjustments to blood flow velocity, aortic stiffness, plasma aldosterone concentration, and sleep apnea did not change these relationships. NMD, but not FMD, is independently associated with unfavorable night-time BP levels and nondipping patterns, and may be a better cardiovascular risk marker in patients with resistant hypertension. BAD also may provide additional prognostic information.

On the random cascading model study of anomalous scaling in multiparticle production with continuously diminishing scale

International Nuclear Information System (INIS)

Liu Lianshou; Zhang Yang; Wu Yuanfang

1996-01-01

The anomalous scaling of factorial moments with continuously diminishing scale is studied using a random cascading model. It is shown that the model currently used have the property of anomalous scaling only for descrete values of elementary cell size. A revised model is proposed which can give good scaling property also for continuously varying scale. It turns out that the strip integral has good scaling property provided the integral regions are chosen correctly, and that this property is insensitive to the concrete way of self-similar subdivision of phase space in the models. (orig.)

Pricing the Ramping Reserve and Capacity Reserve in Real Time Markets

OpenAIRE

Ye, Hongxing; Li, Zuyi

2015-01-01

The increasing penetration of renewable energy in recent years has led to more uncertainties in power systems. In order to maintain system reliability and security, electricity market operators need to keep certain reserves in the Security-Constrained Economic Dispatch (SCED) problems. A new concept, deliverable generation ramping reserve, is proposed in this paper. The prices of generation ramping reserves and generation capacity reserves are derived in the Affine Adjustable Robust Optimizat...

Image-Based Models for Specularity Propagation in Diminished Reality.

Science.gov (United States)

Said, Souheil Hadj; Tamaazousti, Mohamed; Bartoli, Adrien

2018-07-01

The aim of Diminished Reality (DR) is to remove a target object in a live video stream seamlessly. In our approach, the area of the target object is replaced with new texture that blends with the rest of the image. The result is then propagated to the next frames of the video. One of the important stages of this technique is to update the target region with respect to the illumination change. This is a complex and recurrent problem when the viewpoint changes. We show that the state-of-the-art in DR fails in solving this problem, even under simple scenarios. We then use local illumination models to address this problem. According to these models, the variation in illumination only affects the specular component of the image. In the context of DR, the problem is therefore solved by propagating the specularities in the target area. We list a set of structural properties of specularities which we incorporate in two new models for specularity propagation. Our first model includes the same property as the previous approaches, which is the smoothness of illumination variation, but has a different estimation method based on the Thin-Plate Spline. Our second model incorporates more properties of the specularity's shape on planar surfaces. Experimental results on synthetic and real data show that our strategy substantially improves the rendering quality compared to the state-of-the-art in DR.

Trichoderma harzianum containing 1-aminocyclopropane-1-carboxylate deaminase and chitinase improved growth and diminished adverse effect caused by Fusarium oxysporum in soybean.

Science.gov (United States)

Zhang, Fuli; Chen, Can; Zhang, Fan; Gao, Lidong; Liu, Jidong; Chen, Long; Fan, Xiaoning; Liu, Chang; Zhang, Ke; He, Yuting; Chen, Chen; Ji, Xiue

2017-03-01

An isolate, named Trichoderma harzianum T-soybean, showed growth-promoting for soybean seedlings and induced resistance to Fusarium oxysporum under greenhouse. Compared to control soybean seedlings, fresh weight, dry weight, lateral root number, chlorophyll content, root activity and soluble protein of plants pretreated with T-soybean increased, but initial pod height reduced. Furthermore, we found that T-soybean inhibited the growth of F. oxysporum by parasitic function. In addition, plate test results showed that culture filtrates of T-soybean also inhibited significantly F. oxysporum growth. Meanwhile, T-soybean treatment obviously reduced disease severity and induced quickly the H 2 O 2 and O 2 - burst as well as pathogenesis related protein gene (PR3) expression after F. oxysporum inoculation, and subsequently diminished the cell damage in soybean caused by the pathogen challenge. Reactive oxygen species (ROS) scavenging enzymes activity analysis showed that the activities of peroxidase (POD), polyphenol oxidase (PPO) and superoxide dismutase (SOD) increased significantly in T-soybean pretreated plants. These results suggested that T-soybean treatment induced resistance in soybean seedlings to F. oxysporum by companying the production of ROS and the increasing of ROS scavenging enzymes activity as well as PR3 expression. Copyright © 2016 Elsevier GmbH. All rights reserved.

A short educational intervention diminishes causal illusions and specific paranormal beliefs in undergraduates.

Science.gov (United States)

Barberia, Itxaso; Tubau, Elisabet; Matute, Helena; Rodríguez-Ferreiro, Javier

2018-01-01

Cognitive biases such as causal illusions have been related to paranormal and pseudoscientific beliefs and, thus, pose a real threat to the development of adequate critical thinking abilities. We aimed to reduce causal illusions in undergraduates by means of an educational intervention combining training-in-bias and training-in-rules techniques. First, participants directly experienced situations that tend to induce the Barnum effect and the confirmation bias. Thereafter, these effects were explained and examples of their influence over everyday life were provided. Compared to a control group, participants who received the intervention showed diminished causal illusions in a contingency learning task and a decrease in the precognition dimension of a paranormal belief scale. Overall, results suggest that evidence-based educational interventions like the one presented here could be used to significantly improve critical thinking skills in our students.

A short educational intervention diminishes causal illusions and specific paranormal beliefs in undergraduates.

Directory of Open Access Journals (Sweden)

Itxaso Barberia

Full Text Available Cognitive biases such as causal illusions have been related to paranormal and pseudoscientific beliefs and, thus, pose a real threat to the development of adequate critical thinking abilities. We aimed to reduce causal illusions in undergraduates by means of an educational intervention combining training-in-bias and training-in-rules techniques. First, participants directly experienced situations that tend to induce the Barnum effect and the confirmation bias. Thereafter, these effects were explained and examples of their influence over everyday life were provided. Compared to a control group, participants who received the intervention showed diminished causal illusions in a contingency learning task and a decrease in the precognition dimension of a paranormal belief scale. Overall, results suggest that evidence-based educational interventions like the one presented here could be used to significantly improve critical thinking skills in our students.

The pervasive crisis of diminishing radiation therapy access for vulnerable populations in the United States, part 1: African-American patients

Directory of Open Access Journals (Sweden)

Shearwood McClelland, III, MD

2017-10-01

Conclusions: African Americans in the United States have diminished access to RT compared with Caucasian patients, independent of but often in concert with low socioeconomic status. These findings underscore the importance of finding systemic and systematic solutions to address these inequalities to reduce the barriers that patient race provides in receipt of optimal cancer care.

Nitric oxide-dependent vasodilation and Ca2+ signalling induced by erythrodiol in rat aorta

Directory of Open Access Journals (Sweden)

Fidèle Ntchapda

2015-06-01

suggested by functional studies. Conclusions: The present results suggest that the mechanism of relaxation seems to be mainly mediated by the endothelial production of NO. Such a vasorelaxation was an endotheliumdependent effect, via the NO/soluble guanylate cyclase/cyclic guanosine monophosphate pathway. This result also suggests that erythrodiol causes a slow influx of extracellular Ca2+ release from the intracellular Ca2+ stores and an inhibition of Ca2+ extruding mechanism. It can be concluded that erythrodiol may have interesting therapeutic potential as a new vasodilator drug, for protecting the cardiovascular system.

[A comparative study on efficacy of glucocorticoids, mineralocorticoids and vasoactive drugs on reversing hearing loss in patients suffering idiopathic sensorineural cochlear hypoacusis. A preliminary clinical trial].

Science.gov (United States)

Campos-Bañales, Eugenia María; López-Campos, Daniel; de Serdio-Arias, José Luis; Esteban-Rodriguez, J; García-Sáinz, Mar; Muñoz-Cortés, Álvaro; López-Aguado, Daniel

2015-01-01

Sensory neural hearing loss (SNHL) is a disorder characterised by an important deterioration of the auditory function. Re-establishing normal ion homeostasis of the endolymph could be related to hearing recovery and it might be mediated by mineralocorticoids. The main purpose of this preliminary, randomized controlled clinical trial was assessing the recovery of idiopathic sensory neural cochlear hearing loss (SNHL) by comparing the efficacy of 2 types of steroids versus vasodilators. The 3-month intervention involved 70 patients, allocated into 4 different groups: a control with no medication, consisting of 14 patients (8 men and 6 women); a vasodilator group of 21 patients (11 men and 10 women); a glucocorticoid group with 16 patients (10 men and 6 women); and a mineralocorticoid therapy group, consisting of 19 patients (11 men and 8 women). The level of hearing loss and its topography were estimated using Liminal Tone Audiometry (LTA) and Auditory Brainstem Response (ABR). Our research found overall greater efficacy of mineralocorticoids versus glucocorticoids and vasodilators. There was better response in women than in men and it was higher from the left ear, regardless of patient gender. The hearing gain was significantly superior in the mineralocorticoid group, followed by the glucocorticoid group. However, the responses to vasodilators were lesser and of low statistical significance. Copyright © 2014 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

Mitigating Diminishing Manufacturing Sources Material Shortages (DMS/MS) and Obsolescence for the T-6 Canopy Fracturing Initiation System (CFIS)

Science.gov (United States)

2012-03-01

the extra effort to nurse dwindling industries to sustain them becomes a case of diminishing returns. The added cost would be better spent...safety stock is not a prudent or tolerable in the current environment stressing increased efficiencies in defense procurement. Nor should this...NAVAIR, Interview by Author. Interview with NAVAIR JPATS Egress Engineer (2010). Olleros, Francisco-Javier. "Emerging industries and the burnout of

Chicle harvesting and extractive reserves in the Maya Biosphere b: Reserve

Energy Technology Data Exchange (ETDEWEB)

Dugelby, B.L.

1995-12-31

Chicle latex has been extracted from the forests of northern Guatemala for over 100 years and is a key element in the extractive reserve component of the Maya Biosphere Reserve. The carrying capacity of the reserve for chicle extraction can be estimated from a model incorporating ecological data (such as latex yields per tree and population structure of chicle trees, Manilkara zapota, Sapot.) with socio-ecological and political information concerning camp and chicle resource availability, harvester tapping behavior, and historical and present-day institutional organization. I estimate that chicle harvestors currently utilize and area larger than the multiple use zone of the reserve in a unsustainable manner. Simple reduction of harvestors numbers will not ensure sustainability; institutional reforms are also in order. Extractive reserves can play an important role in preserving tropical forests. However, their effectiveness is highly dependent on prevailing ecological, socio-economic, and political conditions. Wise planning and management of extractive reserves demands an understanding of the system`s carrying capacity. In addition, a strong institutional foundation is necessary to assure effective monitoring and enforcement of harvesting regulations.

Extracts of Crataegus oxyacantha and Rosmarinus officinalis Attenuate Ischemic Myocardial Damage by Decreasing Oxidative Stress and Regulating the Production of Cardiac Vasoactive Agents

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Raúl Enrique Cuevas-Durán

2017-11-01

Full Text Available Numerous studies have supported a role for oxidative stress in the development of ischemic damage and endothelial dysfunction. Crataegus oxyacantha (Co and Rosmarinus officinalis (Ro extracts are polyphenolic-rich compounds that have proven to be efficient in the treatment of cardiovascular diseases. We studied the effect of extracts from Co and Ro on the myocardial damage associated with the oxidative status and to the production of different vasoactive agents. Rats were assigned to the following groups: (a sham; (b vehicle-treated myocardial infarction (MI (MI-V; (c Ro extract-treated myocardial infarction (MI-Ro; (d Co extract-treated myocardial infarction (MI-Co; or (e Ro+Co-treated myocardial infarction (MI-Ro+Co. Ro and Co treatments increased total antioxidant capacity, the expression of superoxide dismutase (SOD-Cu2+/Zn2+, SOD-Mn2+, and catalase, with the subsequent decline of malondialdehyde and 8-hydroxy-2′-deoxyguanosine levels. The extracts diminished vasoconstrictor peptide levels (angiotensin II and endothelin-1, increased vasodilators agents (angiotensin 1–7 and bradikinin and improved nitric oxide metabolism. Polyphenol treatment restored the left intraventricular pressure and cardiac mechanical work. We conclude that Ro and Co treatment attenuate morphological and functional ischemic-related changes by both an oxidant load reduction and improvement of the balance between vasoconstrictors and vasodilators.

Pricing of reserves. Valuing system reserve capacity against spot prices in electricity markets

International Nuclear Information System (INIS)

Just, Sebastian; Weber, Christoph

2008-01-01

This paper models the interdependencies between markets for secondary reserve capacity and spot electricity to derive the pricing of reserves under equilibrium conditions. Starting with the indifference condition between offering in both markets, the reservation price is derived from the opportunity cost consideration and the unit commitment conditions in a fundamental interrelated market framework. The reserve market examined compares widely to the German market for secondary reserves, but the general approach may also be used to investigate other reserve markets. The approach explores and formalizes the influence of reserve capacity on the spot market supply function. A numerical solution procedure is provided to this non-trivial case of market interaction. The model is used to estimate the expected reservation price development over the last years in Germany. (author)

A case of diminished pericardial effusion after treatment of a giant hepatic cyst.

Science.gov (United States)

Okano, Hiroshi; Tochio, Tomomasa; Kumazawa, Hiroaki; Isono, Yoshiaki; Tanaka, Hiroki; Matsusaki, Shimpei; Sase, Tomohiro; Saito, Tomonori; Mukai, Katsumi; Nishimura, Akira; Kitamura, Tetsuya; Mori, Takuya

2017-08-01

A 75-year-old woman was discovered to have a pericardial effusion when she was admitted to our hospital because of a giant hepatic cyst. We could not detect the cause of the effusion and diagnosed idiopathic pericardial effusion. The patient underwent transcutaneous drainage of the hepatic cyst and an injection of antibiotics. There was no communication between the pericardial effusion and the hepatic cyst. Although the hepatic cyst was reduced in size, the pericardial effusion showed no remarkable change immediately after treatment; however, 5 months later, the pericardial effusion was found to be diminished. The pericardial effusion might have been caused by the physical pressure of the giant hepatic cyst and disturbance in the balance between the production and reabsorption of the pericardial fluid. When we experience a huge hepatic cyst, we should take into account its influence against the surrounding organs, including the intrapleural space.

Diminished neural responses predict enhanced intrinsic motivation and sensitivity to external incentive.

Science.gov (United States)

Marsden, Karen E; Ma, Wei Ji; Deci, Edward L; Ryan, Richard M; Chiu, Pearl H

2015-06-01

The duration and quality of human performance depend on both intrinsic motivation and external incentives. However, little is known about the neuroscientific basis of this interplay between internal and external motivators. Here, we used functional magnetic resonance imaging to examine the neural substrates of intrinsic motivation, operationalized as the free-choice time spent on a task when this was not required, and tested the neural and behavioral effects of external reward on intrinsic motivation. We found that increased duration of free-choice time was predicted by generally diminished neural responses in regions associated with cognitive and affective regulation. By comparison, the possibility of additional reward improved task accuracy, and specifically increased neural and behavioral responses following errors. Those individuals with the smallest neural responses associated with intrinsic motivation exhibited the greatest error-related neural enhancement under the external contingency of possible reward. Together, these data suggest that human performance is guided by a "tonic" and "phasic" relationship between the neural substrates of intrinsic motivation (tonic) and the impact of external incentives (phasic).

HYDROCARBONS RESERVES IN VENEZUELA

Energy Technology Data Exchange (ETDEWEB)

Gonzalez Cruz, D.J.

2007-07-01

Venezuela is an important player in the energy world, because of its hydrocarbons reserves. The process for calculating oil and associated gas reserves is described bearing in mind that 90% of the gas reserves of Venezuela are associated to oil. Likewise, an analysis is made of the oil reserves figures from 1975 to 2003. Reference is also made to inconsistencies found by international experts and the explanations offered in this respect by the Ministry of Energy and Petroleum (MENPET) and Petroleos de Venezuela (PDVSA) regarding the changes that took place in the 1980s. In turn, Hubbert's Law is explained to determine peak production of conventional oil that a reservoir or field will reach, as well as its relationship with remaining reserves. Emphasis is placed on the interest of the United Nations on this topic. The reserves of associated gas are presented along with their relationship with the different crude oils that are produced and with injected gas, as well as with respect to the possible changes that would take place in the latter if oil reserves are revised. Some recommendations are submitted so that the MENPET starts preparing the pertinent policies ruling reserves. (auth)

US uranium reserves

International Nuclear Information System (INIS)

Hansen, M.V.

1981-01-01

The current low level of demand, compounded by rapidly rising costs and low prices, has caused a significant reduction in drilling for uranium in the United States, and the trend is likely to continue for a few more years. The effect on uranium reserves will be fewer additions to reserves because less exploration is being done. Further reductions will occur, especially in low-cost reserves, because of increasing costs, continuing depletion through production, and erosion through the high grading of deposits to fulfill previous contractual commitments. During the past several years, it has been necessary to increase the upper reserve cost level twice to compensate for rising costs. Rising costs are reducing the $15 reserves, the cost category corresponding most closely to the present market price, to an insignificant level. An encouraging factor related to US uranium reserves is that the US position internationally, as far as quantity is concerned, is not bad for the longer term. Also, there is a general opinion that US consumers would rather contract for domestic uranium than for foreign because of greater assurance of supply. Still another factor, nearly impossible to assess, is what effect rising costs in other countries will have on their uranium reserves. The annual conferences between the Grand Junction Area Office staff and major uranium companies provide a broad overview of the industry's perception of the future. It is not optimistic for the short term. Many companies are reducing their exploration and mining programs; some are switching to other more marketable mineral commodities, and a few are investing more heavily in foreign ventures. However, there is general optimism for the long term, and many predict a growth in demand in the mid-1980s. If the industry can survive the few lean years ahead, rising prices may restore its viability to former levels

Mensuration of cardioangiopulmonary indices by radiocardiogram before and after the verapamil oral administration in subjects with chronic obstructive pulmonary disease. Mensuracao de indices cardiangiopulmonares, atraves do radiocardiograma antes e apos o emprego de verapamil por via oral em portadores de molestia pulmonar obstrutiva cronica

Energy Technology Data Exchange (ETDEWEB)

Lara, P F [Sao Paulo Univ., SP (Brazil). Inst. de Ciencias Biomedicas; Hueb, W A [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina

1982-11-01

Twenty subjects with chronic obstructive pulmonary disease were studied. The diagnosis was obtained from the history, clinical evaluation, pulmonary radiography, pulmonary and hepatic scintigraphies and spirometry. About 360 mg of verapamil was administered daily, every eight hours for ten days. Before and after drug administration, the arterial pressures, the spirometric measurements and nine cardiac roentgenographic indexes were measured. Vital capacity increased in all cases, but did not reach the normal levels. These data suggest that the effect of verapamil on the pulmonary circulation brought benefits to the subjects. This occurred either by direct pulmonary vasodilation, or by bronchodilation, reducing hypoxia. In all cases, the pulmonary resistance was diminished. Finally, verapamil seems to be a drug with real benefits in subjects with chronic obstructive pulmonary disease and we advise a continuation of the studies. (author).

Mensuration of cardioangiopulmonary indices by radiocardiogram before and after the verapamil oral administration in subjects with chronic obstructive pulmonary disease

International Nuclear Information System (INIS)

Lara, P.F.; Hueb, W.A.

1982-01-01

Twenty subjects with chronic obstructive pulmonary disease were studied. The diagnosis was obtained from the history, clinical evaluation, pulmonary radiography, pulmonary and hepatic scintigraphies and spirometry. About 360 mg of verapamil was administered daily, every eight hours for ten days. Before and after drug administration, the arterial pressures, the spirometric measurements and nine cardiac roentgenographic indexes were measured. Vital capacity increased in all cases, but did not reach the normal levels. These data suggest that the effect of verapamil on the pulmonary circulation brought benefits to the subjects. This occurred either by direct pulmonary vasodilation, or by bronchodilation, reducing hypoxia. In all cases, the pulmonary resistance was diminished. Finally, verapamil seems to be a drug with real benefits in subjects with chronic obstructive pulmonary disease and we advise a continuation of the studies. (author)

Diminished physical function in older HIV-infected adults in the Southeastern U.S. despite successful antiretroviral therapy.

Directory of Open Access Journals (Sweden)

Audrey L Khoury

Full Text Available As antiretroviral therapy efficacy improves, HIV is gradually being recognized more as a chronic disease within the aging HIV-infected population. While these individuals are surviving into old age, they may, however, be experiencing "accelerated aging" with greater declines in physical function than that observed among comparably matched individuals free of HIV. This decline is not well understood and it remains unclear if physical decline correlates with the degree of immunosuppression based on CD4 lymphocyte nadir.In a cross-sectional study of accelerated aging in the older HIV-infected population on antiretroviral therapy (ART, physical performance evaluations were completed on a cohort of 107 HIV-infected subjects, age 50 years or older (with no HIV-1 RNA >200 copies/mL in the prior 12 months, and compared to reference ranges for age- and gender-matched HIV-uninfected persons. Physical performance testing consisted of four validated assessments: the 2.4-meter walk, 30-second chair stand, grip strength and 6-minute walk test.When compared to age- and gender-matched HIV-uninfected reference controls, older HIV-infected persons had diminished physical function. No correlation was found between physical function and degree of immunosuppression as determined by pre-ART CD4 nadir.Despite improved survival, HIV-infected adults on suppressive ART have diminished physical function compared to HIV-uninfected persons. The degree of HIV-associated immunosuppression does not correlate with the observed degree of physical function decline in older HIV-infected persons, suggesting the decline is mediated by other mechanisms.

The genetic background affects the vascular response in T-type calcium channels 3.2 deficient mice

DEFF Research Database (Denmark)

Svenningsen, Per; Hansen, Pernille B L

2016-01-01

-type channels are the dominant Ca(2+) entry pathway in vascular smooth muscle cells, however, T-type calcium channels are also expressed in the cardiovascular system where they play a functional role in the regulation of both contraction and vasodilation in (Chen et al. 2003; Hansen et al. 2001). This article...... is protected by copyright. All rights reserved....

Responses to hyperthermia. Optimizing heat dissipation by convection and evaporation: Neural control of skin blood flow and sweating in humans.

Science.gov (United States)

Smith, Caroline J; Johnson, John M

2016-04-01

Under normothermic, resting conditions, humans dissipate heat from the body at a rate approximately equal to heat production. Small discrepancies between heat production and heat elimination would, over time, lead to significant changes in heat storage and body temperature. When heat production or environmental temperature is high the challenge of maintaining heat balance is much greater. This matching of heat elimination with heat production is a function of the skin circulation facilitating heat transport to the body surface and sweating, enabling evaporative heat loss. These processes are manifestations of the autonomic control of cutaneous vasomotor and sudomotor functions and form the basis of this review. We focus on these systems in the responses to hyperthermia. In particular, the cutaneous vascular responses to heat stress and the current understanding of the neurovascular mechanisms involved. The available research regarding cutaneous active vasodilation and vasoconstriction is highlighted, with emphasis on active vasodilation as a major responder to heat stress. Involvement of the vasoconstrictor and active vasodilator controls of the skin circulation in the context of heat stress and nonthermoregulatory reflexes (blood pressure, exercise) are also considered. Autonomic involvement in the cutaneous vascular responses to direct heating and cooling of the skin are also discussed. We examine the autonomic control of sweating, including cholinergic and noncholinergic mechanisms, the local control of sweating, thermoregulatory and nonthermoregulatory reflex control and the possible relationship between sudomotor and cutaneous vasodilator function. Finally, we comment on the clinical relevance of these control schemes in conditions of autonomic dysfunction. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of supplementation with the fat-soluble vitamins E and D on fasting flow-mediated vasodilation in adults: a meta-analysis of randomized controlled trials.

Science.gov (United States)

Joris, Peter J; Mensink, Ronald P

2015-03-10

The effects of fat-soluble vitamin supplementation on cardiovascular disease (CVD) risk are not clear. Therefore, we performed a meta-analysis to quantify effects of fat-soluble vitamin supplements on fasting flow-mediated vasodilation (FMD) of the brachial artery, a validated marker to assess CVD risk. Randomized placebo-controlled trials (RCTs) were identified by a systematic search till July 2014. Seven RCTs studying the effects of vitamin E supplements (range: 300 to 1800 IU per day) and nine RCTs examining the effects of vitamin D supplements, that involved, respectively, 303 and 658 adults, were included. No studies with carotenoid or vitamin K supplements were found. Vitamin E supplementation increased FMD vs. control by 2.42% (95% CI: 0.46% to 4.37%; p = 0.015). No effects of vitamin D supplementation were found (0.15%; 95% CI: -0.21% to 0.51%; p = 0.41). These effects did not depend on subject characteristics, treatment characteristics or technical aspects of the FMD measurement. However, no dose-response relationship was evident for vitamin E, statistical significance depended on one study, while the levels of supplement were far above recommended intakes. The current meta-analysis, therefore, does not provide unambiguous evidence to support the use of fat-soluble vitamin supplements to improve fasting FMD in adults.

Climate Change, Northern Birds of Conservation Concern and Matching the Hotspots of Habitat Suitability with the Reserve Network

Science.gov (United States)

Virkkala, Raimo; Heikkinen, Risto K.; Fronzek, Stefan; Leikola, Niko

2013-01-01

National reserve networks are one of the most important means of species conservation, but their efficiency may be diminished due to the projected climatic changes. Using bioclimatic envelope models and spatial data on habitats and conservation areas, we studied how efficient the reserve network will be in preserving 100 forest, mire, marshland, and alpine bird species of conservation concern in Finland in 2051–2080 under three different climate scenarios. The occurrences of the studied bird species were related to the amount of habitat preferred by each species in the different boreal zones. We employed a novel integrated habitat suitability index that takes into account both the species’ probability of occurrence from the bioclimatic models and the availability of suitable habitat. Using this suitability index, the distribution of the topmost 5% suitability squares (“hotspots”) in the four bird species groups in the period 1971–2000 and under the three scenarios were compared with the location of reserves with the highest amounts of the four habitats to study the efficiency of the network. In species of mires, marshlands, and Arctic mountains, a high proportion of protected habitat was included in the 5% hotspots in the scenarios in 2051–2080, showing that protected areas cover a high proportion of occurrences of bird species. In contrast, in forests in the southern and middle boreal zones, only a small proportion of the protected habitat was included in the 5% hotspots, indicating that the efficiency of the protected area network will be insufficient for forest birds in the future. In the northern boreal zone, the efficiency of the reserve network in forests was highly dependent on the strength of climate change varying between the scenarios. Overall, there is no single solution to preserving biodiversity in a changing climate, but several future pathways should be considered. PMID:23700420

Diminished mental- and physical function and lack of social support are associated with shorter survival in community dwelling older persons of Botswana

Directory of Open Access Journals (Sweden)

Molebatsi Robert M

2007-07-01

Full Text Available Abstract Background Mortality rates for older persons in Botswana have been unavailable and little is known of predictors of mortality in old age. This study may serve as a precursor for more detailed assessments. The objective was to assess diminished function and lack of social support as indicators of short term risk of death. Methods A national population based prospective survey was undertaken in Botswana; twelve rural areas and three urban centers were included. 372 community-dwelling persons aged sixty years and over, were included; 265 were followed-up. Sixteen subjects were deceased at follow-up. Subjects were interviewed and clinically assessed at home. Measures of cognitive function, depression and physical function and sociodemographic information were collected. Subjects were followed-up at average 6.8 months after baseline. Results Overall mortality rate was 10.9 per 100 person years. Age-adjusted odds ratios (OR for death during follow-up were; 4.2 (CI 1.4–12.5 and 3.6 (CI 1.0–12.7 for those with diminished physical- and cognitive function, respectively. Indicators of limited social support; household with only 1 or 2 persons and eating alone, yielded age adjusted ORs of 4.3 (CI 1.5–12.5 and 6.7 (CI 2.2–20, respectively, for death during follow-up. Conclusion Older community dwelling persons with diminished cognitive- or physical function, solitary daily meals and living in a small household have a significantly increased risk of rapid deterioration and death. Health policy should include measures to strengthen informal support and expand formal service provisions to older persons with poor function and limited social networks in order to prevent premature deaths.

Rifaximin diminishes neutropenia following potentially lethal whole-body radiation.

Science.gov (United States)

Jahraus, Christopher D; Schemera, Bettina; Rynders, Patricia; Ramos, Melissa; Powell, Charles; Faircloth, John; Brawner, William R

2010-07-01

Terrorist attacks involving radiological or nuclear weapons are a substantial geopolitical concern, given that large populations could be exposed to potentially lethal doses of radiation. Because of this, evaluating potential countermeasures against radiation-induced mortality is critical. Gut microflora are the most common source of systemic infection following exposure to lethal doses of whole-body radiation, suggesting that prophylactic antibiotic therapy may reduce mortality after radiation exposure. The chemical stability, easy administration and favorable tolerability profile of the non-systemic antibiotic, rifaximin, make it an ideal potential candidate for use as a countermeasure. This study evaluated the use of rifaximin as a countermeasure against low-to-intermediate-dose whole-body radiation in rodents. Female Wistar rats (8 weeks old) were irradiated with 550 cGy to the whole body and were evaluated for 30 d. Animals received methylcellulose, neomycin (179 mg/kg/d) or variably dosed rifaximin (150-2000 mg/kg/d) one hour after irradiation and daily throughout the study period. Clinical assessments (e.g. body weight) were made daily. On postirradiation day 30, blood samples were collected and a complete blood cell count was performed. Animals receiving high doses of rifaximin (i.e. 1000 or 2000 mg/kg/d) had a greater increase in weight from the day of irradiation to postirradiation day 30 compared with animals that received placebo or neomycin. For animals with an increase in average body weight from irradiation day within 80-110% of the group average, methylcellulose rendered an absolute neutrophil count (ANC) of 211, neomycin rendered an ANC of 334, rifaximin 300 mg/kg/d rendered an ANC of 582 and rifaximin 1000 mg/kg/d rendered an ANC of 854 (P = 0.05 for group comparison). Exposure to rifaximin after near-lethal whole-body radiation resulted in diminished levels of neutropenia.

Increased outdoor recreation, diminished ozone layer pose ultraviolet radiation threat to eye

Energy Technology Data Exchange (ETDEWEB)

1989-02-24

The long-term effects of ultraviolet (UV) light on the eye are of increasing concern as many people live longer and spend more of that time in outdoor recreation and as the diminishing ozone layer filters less UV light. Ultraviolet radiation is strongest at high altitude, low latitude, and open for reflective environments (sand, snow, or water). For people who lack an eye lens (aphakics), UV light is transmitted directly onto the retina. Cumulative exposure to the 300- to 400-nm range of UV light is one factor causing cataracts. Ophthalmologists say cataracts cause visual deficits for more than 3.5 million people in the United States. Cumulative UV exposure may lead to age-related macular degeneration. At a Research to Prevent Blindness conference in Arlington, VA, John S. Werner, PhD, professor of psychology and neurosciences at the University of Colorado, Boulder, described how his group demonstrated the effects of UV light on retinal cones. Different types of intraocular lenses were placed in each eye of eight patients who had undergone bilateral cataract surgery. After five years, retinal cones chronically exposured to UV radiation had less sensitivity for short wavelengths (440 nm) by a factor of 1.7.

Growth hormone secretion is diminished and tightly controlled in humans enriched for familial longevity

DEFF Research Database (Denmark)

van der Spoel, Evie; Jansen, Steffy W; Akintola, Abimbola A

2016-01-01

Reduced growth hormone (GH) signaling has been consistently associated with increased health and lifespan in various mouse models. Here, we assessed GH secretion and its control in relation with human familial longevity. We frequently sampled blood over 24 h in 19 middle-aged offspring of long......-living families from the Leiden Longevity Study together with 18 of their partners as controls. Circulating GH concentrations were measured every 10 min and insulin-like growth factor 1 (IGF-1) and insulin-like growth factor binding protein 3 (IGFBP3) every 4 h. Using deconvolution analysis, we found that 24-h.......39-0.53)] compared with controls [0.66 (0.56-0.77)], indicating tighter control of GH secretion. No significant differences were observed in circulating levels of IGF-1 and IGFBP3 between offspring and controls. In conclusion, GH secretion in human familial longevity is characterized by diminished secretion rate...

Initial Study of the Ground Beetles (Coleoptera: Carabidae and Other Invertebrates from “Leshnitsa” Nature Reserve(Central Stara Planina Mountains, Bulgaria

Directory of Open Access Journals (Sweden)

Teodora M. Teofilova

2016-06-01

Full Text Available The invertebrate fauna of the “Leshnitsa” nature reserve was studied, with particular consideration to the ground beetles. During the study altogether 394 specimens of carabid beetlesbelonging to 32 species and subspecies were captured, as well as 23 other invertebrate species,some of which are with a conservation significance (protected, Bulgarian and Balkan endemics.Ground beetles were characterized and classified according to their zoogeographical belonging,degree of endemism and the life forms they refer to. Threats for the invertebrate fauna and negativefactors of anthropogenic origin were determined and measures for diminishing of their effect wereproposed. So far the invertebrate fauna in this part of the mountain has been insufficiently studied.The real state of the diversity of this group in the area will be revealed only after futureinvestigations and discovery of additional new species for the region.

Status of fossil fuel reserves

International Nuclear Information System (INIS)

Laherrere, J.

2005-01-01

Reserves represent the sum of past and future productions up to the end of production. In most countries the reserve data of fields are confidential. Therefore, fossil fuel reserves are badly known because the published data are more political than technical and many countries make a confusion between resources and reserves. The cumulated production of fossil fuels represents only between a third and a fifth of the ultimate reserves. The production peak will take place between 2020 and 2050. In the ultimate reserves, which extrapolate the past, the fossil fuels represent three thirds of the overall energy. This document analyses the uncertainties linked with fossil fuel reserves: reliability of published data, modeling of future production, comparison with other energy sources, energy consumption forecasts, reserves/production ratio, exploitation of non-conventional hydrocarbons (tar sands, extra-heavy oils, bituminous shales, coal gas, gas shales, methane in overpressure aquifers, methane hydrates), technology impacts, prices impact, and reserves growth. (J.S.)

Alterations in vasodilator-stimulated phosphoprotein (VASP) phosphorylation: associations with asthmatic phenotype, airway inflammation and β2-agonist use

Science.gov (United States)

Hastie, Annette T; Wu, Min; Foster, Gayle C; Hawkins, Gregory A; Batra, Vikas; Rybinski, Katherine A; Cirelli, Rosemary; Zangrilli, James G; Peters, Stephen P

2006-01-01

Background Vasodilator-stimulated phosphoprotein (VASP) mediates focal adhesion, actin filament binding and polymerization in a variety of cells, thereby inhibiting cell movement. Phosphorylation of VASP via cAMP and cGMP dependent protein kinases releases this "brake" on cell motility. Thus, phosphorylation of VASP may be necessary for epithelial cell repair of damage from allergen-induced inflammation. Two hypotheses were examined: (1) injury from segmental allergen challenge increases VASP phosphorylation in airway epithelium in asthmatic but not nonasthmatic normal subjects, (2) regular in vivo β2-agonist use increases VASP phosphorylation in asthmatic epithelium, altering cell adhesion. Methods Bronchial epithelium was obtained from asthmatic and non-asthmatic normal subjects before and after segmental allergen challenge, and after regularly inhaled albuterol, in three separate protocols. VASP phosphorylation was examined in Western blots of epithelial samples. DNA was obtained for β2-adrenergic receptor haplotype determination. Results Although VASP phosphorylation increased, it was not significantly greater after allergen challenge in asthmatics or normals. However, VASP phosphorylation in epithelium of nonasthmatic normal subjects was double that observed in asthmatic subjects, both at baseline and after challenge. Regularly inhaled albuterol significantly increased VASP phosphorylation in asthmatic subjects in both unchallenged and antigen challenged lung segment epithelium. There was also a significant increase in epithelial cells in the bronchoalveolar lavage of the unchallenged lung segment after regular inhalation of albuterol but not of placebo. The haplotypes of the β2-adrenergic receptor did not appear to associate with increased or decreased phosphorylation of VASP. Conclusion Decreased VASP phosphorylation was observed in epithelial cells of asthmatics compared to nonasthmatic normals, despite response to β-agonist. The decreased

Alterations in vasodilator-stimulated phosphoprotein (VASP phosphorylation: associations with asthmatic phenotype, airway inflammation and β2-agonist use

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Cirelli Rosemary

2006-02-01

Full Text Available Abstract Background Vasodilator-stimulated phosphoprotein (VASP mediates focal adhesion, actin filament binding and polymerization in a variety of cells, thereby inhibiting cell movement. Phosphorylation of VASP via cAMP and cGMP dependent protein kinases releases this "brake" on cell motility. Thus, phosphorylation of VASP may be necessary for epithelial cell repair of damage from allergen-induced inflammation. Two hypotheses were examined: (1 injury from segmental allergen challenge increases VASP phosphorylation in airway epithelium in asthmatic but not nonasthmatic normal subjects, (2 regular in vivo β2-agonist use increases VASP phosphorylation in asthmatic epithelium, altering cell adhesion. Methods Bronchial epithelium was obtained from asthmatic and non-asthmatic normal subjects before and after segmental allergen challenge, and after regularly inhaled albuterol, in three separate protocols. VASP phosphorylation was examined in Western blots of epithelial samples. DNA was obtained for β2-adrenergic receptor haplotype determination. Results Although VASP phosphorylation increased, it was not significantly greater after allergen challenge in asthmatics or normals. However, VASP phosphorylation in epithelium of nonasthmatic normal subjects was double that observed in asthmatic subjects, both at baseline and after challenge. Regularly inhaled albuterol significantly increased VASP phosphorylation in asthmatic subjects in both unchallenged and antigen challenged lung segment epithelium. There was also a significant increase in epithelial cells in the bronchoalveolar lavage of the unchallenged lung segment after regular inhalation of albuterol but not of placebo. The haplotypes of the β2-adrenergic receptor did not appear to associate with increased or decreased phosphorylation of VASP. Conclusion Decreased VASP phosphorylation was observed in epithelial cells of asthmatics compared to nonasthmatic normals, despite response to �

Overexpression of Catalase Diminishes Oxidative Cysteine Modifications of Cardiac Proteins.

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Chunxiang Yao

Full Text Available Reactive protein cysteine thiolates are instrumental in redox regulation. Oxidants, such as hydrogen peroxide (H2O2, react with thiolates to form oxidative post-translational modifications, enabling physiological redox signaling. Cardiac disease and aging are associated with oxidative stress which can impair redox signaling by altering essential cysteine thiolates. We previously found that cardiac-specific overexpression of catalase (Cat, an enzyme that detoxifies excess H2O2, protected from oxidative stress and delayed cardiac aging in mice. Using redox proteomics and systems biology, we sought to identify the cysteines that could play a key role in cardiac disease and aging. With a 'Tandem Mass Tag' (TMT labeling strategy and mass spectrometry, we investigated differential reversible cysteine oxidation in the cardiac proteome of wild type and Cat transgenic (Tg mice. Reversible cysteine oxidation was measured as thiol occupancy, the ratio of total available versus reversibly oxidized cysteine thiols. Catalase overexpression globally decreased thiol occupancy by ≥1.3 fold in 82 proteins, including numerous mitochondrial and contractile proteins. Systems biology analysis assigned the majority of proteins with differentially modified thiols in Cat Tg mice to pathways of aging and cardiac disease, including cellular stress response, proteostasis, and apoptosis. In addition, Cat Tg mice exhibited diminished protein glutathione adducts and decreased H2O2 production from mitochondrial complex I and II, suggesting improved function of cardiac mitochondria. In conclusion, our data suggest that catalase may alleviate cardiac disease and aging by moderating global protein cysteine thiol oxidation.

Biosphere reserves: Attributes for success.

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Van Cuong, Chu; Dart, Peter; Hockings, Marc

2017-03-01

Biosphere reserves established under the UNESCO Man and the Biosphere Program aim to harmonise biodiversity conservation and sustainable development. Concerns over the extent to which the reserve network was living up to this ideal led to the development of a new strategy in 1995 (the Seville Strategy) to enhance the operation of the network of reserves. An evaluation of effectiveness of management of the biosphere reserve network was called for as part of this strategy. Expert opinion was assembled through a Delphi Process to identify successful and less successful reserves and investigate common factors influencing success or failure. Ninety biosphere reserves including sixty successful and thirty less successful reserves in 42 countries across all five Man and the Biosphere Program regions were identified. Most successful sites are the post-Seville generation while the majority of unsuccessful sites are pre-Seville that are managed as national parks and have not been amended to conform to the characteristics that are meant to define a biosphere reserve. Stakeholder participation and collaboration, governance, finance and resources, management, and awareness and communication are the most influential factors in the success or failure of the biosphere reserves. For success, the biosphere reserve concept needs to be clearly understood and applied through landscape zoning. Designated reserves then need a management system with inclusive good governance, strong participation and collaboration, adequate finance and human resource allocation and stable and responsible management and implementation. All rather obvious but it is difficult to achieve without commitment to the biosphere reserve concept by the governance authorities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Failure to demonstrate that playing violent video games diminishes prosocial behavior.

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Tear, Morgan J; Nielsen, Mark

2013-01-01

Past research has found that playing a classic prosocial video game resulted in heightened prosocial behavior when compared to a control group, whereas playing a classic violent video game had no effect. Given purported links between violent video games and poor social behavior, this result is surprising. Here our aim was to assess whether this finding may be due to the specific games used. That is, modern games are experienced differently from classic games (more immersion in virtual environments, more connection with characters, etc.) and it may be that playing violent video games impacts prosocial behavior only when contemporary versions are used. Experiments 1 and 2 explored the effects of playing contemporary violent, non-violent, and prosocial video games on prosocial behavior, as measured by the pen-drop task. We found that slight contextual changes in the delivery of the pen-drop task led to different rates of helping but that the type of game played had little effect. Experiment 3 explored this further by using classic games. Again, we found no effect. We failed to find evidence that playing video games affects prosocial behavior. Research on the effects of video game play is of significant public interest. It is therefore important that speculation be rigorously tested and findings replicated. Here we fail to substantiate conjecture that playing contemporary violent video games will lead to diminished prosocial behavior.

Increased conformity offers diminishing returns for reducing total knee replacement wear.

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Fregly, Benjamin J; Marquez-Barrientos, Carlos; Banks, Scott A; DesJardins, John D

2010-02-01

Wear remains a significant problem limiting the lifespan of total knee replacements (TKRs). Though increased conformity between TKR components has the potential to decrease wear, the optimal amount and planes of conformity have not been investigated. Furthermore, differing conformities in the medial and lateral compartments may provide designers the opportunity to address both wear and kinematic design goals simultaneously. This study used a computational model of a Stanmore knee simulator machine and a previously validated wear model to investigate this issue for simulated gait. TKR geometries with different amounts and planes of conformity on the medial and lateral sides were created and tested in two phases. The first phase utilized a wide range of sagittal and coronal conformity combinations to blanket a physically realistic design space. The second phase performed a focused investigation of the conformity conditions from the first phase to which predicted wear volume was sensitive. For the first phase, sagittal but not coronal conformity was found to have a significant effect on predicted wear volume. For the second phase, increased sagittal conformity was found to decrease predicted wear volume in a nonlinear fashion, with reductions gradually diminishing as conformity increased. These results suggest that TKR geometric design efforts aimed at minimizing wear should focus on sagittal rather than coronal conformity and that at least moderate sagittal conformity is desirable in both compartments.

Application of ecological criteria in selecting marine reserves and developing reserve networks

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Roberts, Callum M.; Branch, George; Bustamante, Rodrigo H.; Castilla, Juan Carlos; Dugan, Jenifer; Halpern, Benjamin S.; Lafferty, Kevin D.; Leslie, Heather; McArdle, Deborah; Ruckelshaus, Mary; Warner, Robert R.

2003-01-01

Marine reserves are being established worldwide in response to a growing recognition of the conservation crisis that is building in the oceans. However, designation of reserves has been largely opportunistic, or protective measures have been implemented (often overlapping and sometimes in conflict) by different entities seeking to achieve different ends. This has created confusion among both users and enforcers, and the proliferation of different measures provides a false sense of protection where little is offered. This paper sets out a procedure grounded in current understanding of ecological processes, that allows the evaluation and selection of reserve sites in order to develop functional, interconnected networks of fully protected reserves that will fulfill multiple objectives. By fully protected we mean permanently closed to fishing and other resource extraction. We provide a framework that unifies the central aims of conservation and fishery management, while also meeting other human needs such as the provision of ecosystem services (e.g., maintenance of coastal water quality, shoreline protection, and recreational opportunities). In our scheme, candidate sites for reserves are evaluated against 12 criteria focused toward sustaining the biological integrity and productivity of marine systems at both local and regional scales. While a limited number of sites will be indispensable in a network, many will be of similar value as reserves, allowing the design of numerous alternative, biologically adequate networks. Devising multiple network designs will help ensure that ecological functionality is preserved throughout the socioeconomic evaluation process. Too often, socioeconomic criteria have dominated the process of reserve selection, potentially undermining their efficacy. We argue that application of biological criteria must precede and inform socioeconomic evaluation, since maintenance of ecosystem functioning is essential for meeting all of the goals for

Reflex peripheral vasoconstriction is diminished in older men.

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Kenney, W L; Armstrong, C G

1996-02-01

The purpose of this study was to compare reflex control of limb blood flow in healthy young (Y; 26 +/- 2 yr) and older (O;61 +/- 2 yr) men during whole body cooling under resting conditions. To better isolate the effect of chronological age, the two age groups (n = 6 per group) were closely matched for maximal oxygen uptake, body surface area, skinfold thickness, and fat-free weight. Subjects sat in an environmentally controlled chamber clad in standardized (0.6-clo) light cotton clothing at a dry-bulb temperature (Tdb) of 28 degrees C. After 30 min, Tdb was decreased by 2 degrees C every 5 min until Tdb = 10 degrees C, where it was held constant for the remainder of the 120-min session. Esophageal and mean skin temperatures were monitored continuously. Forearm blood flow (FBF) was measured every 5 min by venous occlusion plethysmography by using a mercury-in-Silastic strain gauge while arm temperature between the wrist and elbow was clamped at 37.2 +/- 0.1 degrees C by localized warm air heating. In this way, limb vasoconstriction was driven solely by thermoregulatory reflexes and not by direct effects of localized cooling. Mean skin temperature decreased at a similar rate and to a similar extent (by approximately 6 degrees C over a 2-h period) in both age groups, whereas esophageal temperature was relatively unaffected. In response to the local heating, the Y group maintained a significantly higher FBF than did the O group during the initial 30 min but decreased FBF during the cooling phase at a greater rate and to a greater extent than did the O group, leading to a significantly lower FBF during the final 30 min (at Tdb = 10 degrees C). Because there was no age difference in the mean arterial pressure response, similar effects of age were seen on forearm vascular conductance (FBF/mean arterial pressure). It was concluded that older men have a diminished reflex limb vasoconstrictor response to skin cooling. Furthermore, this difference in control of peripheral

Mechanisms of endothelial dysfunction in resistance arteries from patients with end-stage renal disease.

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Leanid Luksha

Full Text Available The study focuses on the mechanisms of endothelial dysfunction in the uremic milieu. Subcutaneous resistance arteries from 35 end-stage renal disease (ESRD patients and 28 matched controls were studied ex-vivo. Basal and receptor-dependent effects of endothelium-derived factors, expression of endothelial NO synthase (eNOS, prerequisites for myoendothelial gap junctions (MEGJ, and associations between endothelium-dependent responses and plasma levels of endothelial dysfunction markers were assessed. The contribution of endothelium-derived hyperpolarizing factor (EDHF to endothelium-dependent relaxation was impaired in uremic arteries after stimulation with bradykinin, but not acetylcholine, reflecting the agonist-specific differences. Diminished vasodilator influences of the endothelium on basal tone and enhanced plasma levels of asymmetrical dimethyl L-arginine (ADMA suggest impairment in NO-mediated regulation of uremic arteries. eNOS expression and contribution of MEGJs to EDHF type responses were unaltered. Plasma levels of ADMA were negatively associated with endothelium-dependent responses in uremic arteries. Preserved responses of smooth muscle to pinacidil and NO-donor indicate alterations within the endothelium and tolerance of vasodilator mechanisms to the uremic retention products at the level of smooth muscle. We conclude that both EDHF and NO pathways that control resistance artery tone are impaired in the uremic milieu. For the first time, we validate the alterations in EDHF type responses linked to kinin receptors in ESRD patients. The association between plasma ADMA concentrations and endothelial function in uremic resistance vasculature may have diagnostic and future therapeutic implications.

The cytotoxicity of organobismuth compounds with certain molecular structures can be diminished by replacing the bismuth atom with an antimony atom in the molecules.

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Kohri, Kumiko; Yoshida, Eiko; Yasuike, Shuji; Fujie, Tomoya; Yamamoto, Chika; Kaji, Toshiyuki

2015-06-01

Organic-inorganic hybrid molecules, which are composed of an organic structure and metal(s), are indispensable for synthetic chemical reactions; however, their toxicity has been incompletely understood. In the present study, we discovered two cytotoxic organobismuth compounds whose cytotoxicity diminished upon replacement of the intramolecular bismuth atom with an antimony atom. The intracellular accumulation of the organobismuth compounds was much higher than that of the organoantimony compounds with the corresponding organic structures. We also showed that both the organic structure and bismuth atom are required for certain organobismuth compounds to exert their cytotoxic effect, suggesting that the cytotoxicity of such a compound is a result of an interaction between the organic structure and the bismuth atom. The present data suggest that organobismuth compounds with certain molecular structures exhibit cytotoxicity via an interaction between the molecular structure and the bismuth atom, and this cytotoxicity can be diminished by replacing the bismuth atom with an antimony atom, resulting in lower intracellular accumulation.

Diagnostic performance of instantaneous wave-free ratio for the evaluation of coronary stenosis severity confirmed by fractional flow reserve: A PRISMA-compliant meta-analysis of randomized studies.

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Man, Wanrong; Hu, Jianqiang; Zhao, Zhijing; Zhang, Mingming; Wang, Tingting; Lin, Jie; Duan, Yu; Wang, Ling; Wang, Haichang; Sun, Dongdong; Li, Yan

2016-09-01

The instantaneous wave-free ratio (iFR) is a new vasodilator-free index of coronary stenosis severity. The aim of this meta-analysis is to assess the diagnostic performance of iFR for the evaluation of coronary stenosis severity with fractional flow reserve as standard reference. We searched PubMed, EMBASE, CENTRAL, ProQuest, Web of Science, and International Clinical Trials Registry Platform (ICTRP) for publications concerning the diagnostic value of iFR. We used a random-effects covariate to synthesize the available data of sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR-), and diagnostic odds ratio (DOR). Overall test performance was summarized by the summary receiver operating characteristic curve (sROC) and the area under the curve (AUC). Eight studies with 1611 subjects were included in the meta-analysis. The pooled sensitivity, specificity, LR+, LR-, and DOR for iFR were respectively 73.3% (70.1-76.2%), 86.4% (84.3-88.3%), 5.71 (4.43-7.37), 0.29 (0.22-0.38), and 20.54 (16.11-26.20). The area under the summary receiver operating characteristic curves for iFR was 0.8786. No publication bias was identified. The available evidence suggests that iFR may be a new, simple, and promising technology for coronary stenosis physiological assessment.

[The contribution of endogenous vasodilators to the control of glomerular hemodynamics].

Science.gov (United States)

Arima, S; Ito, S; Abe, K

1994-06-01

Preglomerular afferent (Af-) and postglomerular efferent arterioles (Ef-Arts) are crucial vascular segments in the control of glomerular hemodynamics. However, their vascular reactivity is not fully understood. We examined: 1) their responses to angiotensin II (AII) or norepinephrine (NE), and 2) the possible modulatory roles of nitric oxide (NO) and prostaglandins (PGs) in these responses. Rabbit Af- or Ef-Arts were microperfused in vitro. Ef-Arts were perfused in either the orthograde direction from the distal end of Af-Arts through the glomerulus (OP) or the retrograde direction from its distal end to eliminate the influence of the glomerulus (RP). Although AII and NE constricted both arterioles in a dose-dependent manner, sensitivity to AII was higher in Ef-Arts. AII began to cause significant (P Arts, and from 10(-11) M in Ef-Arts (OP; 11 +/- 4%, n = 9. RP; 10 +/- 2%, n = 5). In addition, both AII and NE produced stronger constriction of Ef-Arts in RP than OP; AII at 10(-8) M or NE at 10(-6) M decreased the diameter by 35 +/- 4% or 25 +/- 4% in OP and 74 +/- 4% or 62 +/- 7% in RP. NO synthesis inhibitor nitro-L-arginine (L-NAME; 10(-4) M) increased the sensitivity of Af-Art to AII without affecting the reactivity of Ef-Art; in L-NAME-pretreated Af-Arts, AII began to cause significant constriction from 10(-10) M (14 +/- 4%, n = 9, P Arts without affecting different vascular responses between OP and RP. Indomethacin (5 x 10(-5) M) significantly augmented the AII- or NE-induced Ef-Art constriction only in OP; AII at 10(-8) M or NE at 10(-6) M decreased the diameter by 72 +/- 5% (n = 8) or 48 +/- 3% (n = 7). Thus, indomethacin-pretreatment markedly diminished the differences in responses between OP and RP. These results suggest that 1) NO modulates AII action only in the Af-Art, contributing to the difference in sensitivity to AII between Af- and Ef-Art, and 2) the glomerulus controls vascular reactivity of the downstream Ef-Art by releasing PGs.

Assessment of vasodilator therapy in patients with severe congestive heart failure: limitations of measurements of left ventricular ejection fraction and volumes

International Nuclear Information System (INIS)

Firth, B.G.; Dehmer, G.J.; Markham, R.V. Jr.; Willerson, J.T.; Hillis, L.D.

1982-01-01

Although noninvasive techniques are often used to assess the effect of vasodilator therapy in patients with congestive heart failure, it is unknown whether changes in noninvasively determined left ventricular ejection fraction, volume, or dimension reliably reflect alterations in intracardiac pressure and flow. Accordingly, we compared the acute effect of sodium nitroprusside on left ventricular volume and ejection fraction (determined scintigraphically) with its effect on intracardiac pressure and forward cardiac index (determined by thermodilution) in 12 patients with severe, chronic congestive heart failure and a markedly dilated left ventricle. Nitroprusside (infused at 1.3 +/- 1.1 [mean +/- standard deviation] microgram/kg/min) caused a decrease in mean systemic arterial, mean pulmonary arterial, and mean pulmonary capillary wedge pressure as well as a concomitant increase in forward cardiac index. Simultaneously, left ventricular end-diastolic and end-systolic volume indexes decreased, but the scintigraphically determined cardiac index did not change significantly. Left ventricular ejection fraction averaged 0.19 +/- 0.05 before nitroprusside administration and increased by less than 0.05 units in response to nitroprusside in 11 of 12 patients. The only significant correlation between scintigraphically and invasively determined variables was that between the percent change in end-diastolic volume index and the percent change in pulmonary capillary wedge pressure (r . 0.68, p . 0.01). Although nitroprusside produced changes in scintigraphically determined left ventricular ejection fraction, end-systolic volume index, and cardiac index, these alterations bore no predictable relation to changes in intracardiac pressure, forward cardiac index, or vascular resistance. Furthermore, nitroprusside produced a considerably greater percent change in the invasively measured variables than in the scintigraphically determined ones

Disaggregating reserve-to-production ratios: An algorithm for United States oil and gas reserve development

Science.gov (United States)

Williams, Charles William

Reserve-to-production ratios for oil and gas development are utilized by oil and gas producing states to monitor oil and gas reserve and production dynamics. These ratios are used to determine production levels for the manipulation of oil and gas prices while maintaining adequate reserves for future development. These aggregate reserve-to-production ratios do not provide information concerning development cost and the best time necessary to develop newly discovered reserves. Oil and gas reserves are a semi-finished inventory because development of the reserves must take place in order to implement production. These reserves are considered semi-finished in that they are not counted unless it is economically profitable to produce them. The development of these reserves is encouraged by profit maximization economic variables which must consider the legal, political, and geological aspects of a project. This development is comprised of a myriad of incremental operational decisions, each of which influences profit maximization. The primary purpose of this study was to provide a model for characterizing a single product multi-period inventory/production optimization problem from an unconstrained quantity of raw material which was produced and stored as inventory reserve. This optimization was determined by evaluating dynamic changes in new additions to reserves and the subsequent depletion of these reserves with the maximization of production. A secondary purpose was to determine an equation for exponential depletion of proved reserves which presented a more comprehensive representation of reserve-to-production ratio values than an inadequate and frequently used aggregate historical method. The final purpose of this study was to determine the most accurate delay time for a proved reserve to achieve maximum production. This calculated time provided a measure of the discounted cost and calculation of net present value for developing new reserves. This study concluded that

Thyroid autoimmunity, hypothyroidism and ovarian reserve: a cross-sectional study of 5000 women based on age-specific AMH values.

Science.gov (United States)

Polyzos, Nikolaos P; Sakkas, Evangelos; Vaiarelli, Alberto; Poppe, Kris; Camus, Michel; Tournaye, Herman

2015-07-01

Is there any association between thyroid autoimmunity (TAI) and diminished ovarian reserve (DOR)? TAI and hypothyroidism are not associated with low ovarian reserve. TAI is a common co-existent endocrinopathy in women with primary ovarian insufficiency. Several studies support a potential link between TAI and the reduction in ovarian reserve. However, robust evidence regarding its prevalence in women with DOR is lacking. This study is a large cross-sectional analysis of retrospective data from the Centre for Reproductive Medicine/University Hospital of Brussels. Serum measurements were taken for anti-Mullerian hormone (AMH), free thyroxine (FT4), thyroid-stimulating hormone (TSH) and anti-thyroperoxidase (anti-TPO). Among 5076 consecutive women, 4894 women had their AMH, FT4, TSH and anti-TPO levels measured on the same day. AMH levels were plotted in relation to age for the whole patients' cohort and age-specific AMH values (per year) were considered in order to categorize women according to the AMH levels of ovarian reserve. There were 3929 women who demonstrated normal reserve, 487 women who had low ovarian reserve and 478 women who demonstrated high ovarian reserve. Serum FT4 and TSH levels were comparable between different ovarian reserve categories (P = 0.611 and 0.811, respectively). No significant differences were observed in the prevalence of positive anti-TPO antibodies among women with low (12.1%), normal (10.3%) and high (9.8%) ovarian reserve (P = 0.423). Finally, the prevalence of overt or subclinical hypothyroidism was comparable between the groups (4.1% in low, 4.6% in normal and 3.8% in high ovarian reserve women, P = 0.645).Analysis according to the exact cause of low ovarian reserve demonstrated that women with a genetic cause of low ovarian reserve had a significantly higher prevalence of overt hypothyroidism and subclinical hypothyroidism compared with women with unexplained low ovarian reserve for their age (25 versus 3.2%, P = 0.002 and 18

Perivascular adipose tissue control of insulin-induced vasoreactivity in muscle is impaired in db/db mice

DEFF Research Database (Denmark)

Meijer, Rick I; Bakker, Wineke; Alta, Caro-Lynn A F

2013-01-01

in muscle, the underlying mechanisms, and how obesity disturbs this vasodilation. Insulin-induced vasoreactivity of resistance arteries was studied with PVAT from C57BL/6 or db/db mice. PVAT weight in muscle was higher in db/db mice compared with C57BL/6 mice. PVAT from C57BL/6 mice uncovered insulin......-induced vasodilation; this vasodilation was abrogated with PVAT from db/db mice. Blocking adiponectin abolished the vasodilator effect of insulin in the presence of C57BL/6 PVAT, and adiponectin secretion was lower in db/db PVAT. To investigate this interaction further, resistance arteries of AMPKa2(+/+) and AMPKa2......-induced vasodilation in an adiponectin-dependent manner. In conclusion, PVAT controls insulin-induced vasoreactivity in the muscle microcirculation through secretion of adiponectin and subsequent AMPKa2 signaling. PVAT from obese mice inhibits insulin-induced vasodilation, which can be restored by inhibition of JNK....

Inward rectifier potassium (Kir2.1) channels as end‐stage boosters of endothelium‐dependent vasodilators

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Dalsgaard, Thomas; Bonev, Adrian D.; Nelson, Mark T.

2016-01-01

Key points Increase in endothelial cell (EC) calcium activates calcium‐sensitive intermediate and small conductance potassium (IK and SK) channels, thereby causing hyperpolarization and endothelium‐dependent vasodilatation.Endothelial cells express inward rectifier potassium (Kir) channels, but their role in endothelium‐dependent vasodilatation is not clear.In the mesenteric arteries, only ECs, but not smooth muscle cells, displayed Kir currents that were predominantly mediated by the Kir2.1 isoform.Endothelium‐dependent vasodilatations in response to muscarinic receptor, TRPV4 (transient receptor potential vanilloid 4) channel and IK/SK channel agonists were highly attenuated by Kir channel inhibitors and by Kir2.1 channel knockdown.These results point to EC Kir channels as amplifiers of vasodilatation in response to increases in EC calcium and IK/SK channel activation and suggest that EC Kir channels could be targeted to treat endothelial dysfunction, which is a hallmark of vascular disorders. Abstract Endothelium‐dependent vasodilators, such as acetylcholine, increase intracellular Ca2+ through activation of transient receptor potential vanilloid 4 (TRPV4) channels in the plasma membrane and inositol trisphosphate receptors in the endoplasmic reticulum, leading to stimulation of Ca2+‐sensitive intermediate and small conductance K+ (IK and SK, respectively) channels. Although strong inward rectifier K+ (Kir) channels have been reported in the native endothelial cells (ECs) their role in EC‐dependent vasodilatation is not clear. Here, we test the idea that Kir channels boost the EC‐dependent vasodilatation of resistance‐sized arteries. We show that ECs, but not smooth muscle cells, of small mesenteric arteries have Kir currents, which are substantially reduced in EC‐specific Kir2.1 knockdown (EC‐Kir2.1 −/−) mice. Elevation of extracellular K+ to 14 mm caused vasodilatation of pressurized arteries, which was prevented by endothelial

Inward rectifier potassium (Kir2.1) channels as end-stage boosters of endothelium-dependent vasodilators.

Science.gov (United States)

Sonkusare, Swapnil K; Dalsgaard, Thomas; Bonev, Adrian D; Nelson, Mark T

2016-06-15

Increase in endothelial cell (EC) calcium activates calcium-sensitive intermediate and small conductance potassium (IK and SK) channels, thereby causing hyperpolarization and endothelium-dependent vasodilatation. Endothelial cells express inward rectifier potassium (Kir) channels, but their role in endothelium-dependent vasodilatation is not clear. In the mesenteric arteries, only ECs, but not smooth muscle cells, displayed Kir currents that were predominantly mediated by the Kir2.1 isoform. Endothelium-dependent vasodilatations in response to muscarinic receptor, TRPV4 (transient receptor potential vanilloid 4) channel and IK/SK channel agonists were highly attenuated by Kir channel inhibitors and by Kir2.1 channel knockdown. These results point to EC Kir channels as amplifiers of vasodilatation in response to increases in EC calcium and IK/SK channel activation and suggest that EC Kir channels could be targeted to treat endothelial dysfunction, which is a hallmark of vascular disorders. Endothelium-dependent vasodilators, such as acetylcholine, increase intracellular Ca(2+) through activation of transient receptor potential vanilloid 4 (TRPV4) channels in the plasma membrane and inositol trisphosphate receptors in the endoplasmic reticulum, leading to stimulation of Ca(2+) -sensitive intermediate and small conductance K(+) (IK and SK, respectively) channels. Although strong inward rectifier K(+) (Kir) channels have been reported in the native endothelial cells (ECs) their role in EC-dependent vasodilatation is not clear. Here, we test the idea that Kir channels boost the EC-dependent vasodilatation of resistance-sized arteries. We show that ECs, but not smooth muscle cells, of small mesenteric arteries have Kir currents, which are substantially reduced in EC-specific Kir2.1 knockdown (EC-Kir2.1(-/-) ) mice. Elevation of extracellular K(+) to 14 mm caused vasodilatation of pressurized arteries, which was prevented by endothelial denudation and Kir channel

Application of the Diminishing Returns Concept in the Hydroecologic Restoration of Riverscapes

International Nuclear Information System (INIS)

Diefenderfer, Heida L.; Johnson, Gary E.; Skalski, John R.; Breithaupt, Stephen A.; Coleman, Andre M.

2012-01-01

Principles for optimizing the number and placement of ecological restoration actions on rivers and coasts would be useful in project engineering design and program planning. This study demonstrated that the yield of inundated floodplain habitat area from dike breaching conforms to a diminishing returns model. The aggregate effects of establishing hydrologic connections between a tidally influenced main stem river and the floodplain were experimentally examined using a hydrodynamic model. Restoration clusters of size 1, 4, 8, and more, replicated and randomized within the landscape, yielded average wetted floodplain area conforming with an exponential rise to maximum curve2(0.99)r=. Analysis of the average incremental change in floodplain inundation produced per breach showed that opening 25 % of the channels crossing the dike provided the maximum return on investment as measured by wetted area. Midstream breaches yielded 60 % and upstream breaches 2 % of the wetted area produced by downstream breaches. Dike-breach restoration programs therefore can be optimized by strategic determination of the spatial configuration and number of demolitions, though biological factors such as the accessibility of floodplain habitat and total length of channels connected also need to be considered. These findings have implications for cost-benefit analyses in restoration program planning.

Akt1 deficiency diminishes skeletal muscle hypertrophy by reducing satellite cell proliferation.

Science.gov (United States)

Moriya, Nobuki; Miyazaki, Mitsunori

2018-02-14

Skeletal muscle mass is determined by the net dynamic balance between protein synthesis and degradation. Although the Akt/mechanistic target of rapamycin (mTOR)-dependent pathway plays an important role in promoting protein synthesis and subsequent skeletal muscle hypertrophy, the precise molecular regulation of mTOR activity by the upstream protein kinase Akt is largely unknown. In addition, the activation of satellite cells has been indicated as a key regulator of muscle mass. However, the requirement of satellite cells for load-induced skeletal muscle hypertrophy is still under intense debate. In this study, female germline Akt1 knockout (KO) mice were used to examine whether Akt1 deficiency attenuates load-induced skeletal muscle hypertrophy through suppressing mTOR-dependent signaling and satellite cell proliferation. Akt1 KO mice showed a blunted hypertrophic response of skeletal muscle, with a diminished rate of satellite cell proliferation following mechanical overload. In contrast, Akt1 deficiency did not affect the load-induced activation of mTOR signaling and the subsequent enhanced rate of protein synthesis in skeletal muscle. These observations suggest that the load-induced activation of mTOR signaling occurs independently of Akt1 regulation and that Akt1 plays a critical role in regulating satellite cell proliferation during load-induced muscle hypertrophy.

Renal and femoral venous blood flows are regulated by different mechanisms dependent on α-adrenergic receptor subtypes and nitric oxide in anesthetized rats.

Science.gov (United States)

Fioretti, Alexandre C; Ogihara, Cristiana A; Cafarchio, Eduardo M; Venancio, Daniel P; de Almeida, Roberto Lopes; Antonio, Bruno B; Sato, Monica A

2017-12-01

Venous and arterial walls are responsive to sympathetic system and circulating substances, nevertheless, very few is known about the venous blood flow regulation simultaneously to arterial vascular beds. In this study, we compared the venous and arterial blood flow regulation in visceral and muscular beds upon injection of different doses of vasoactive drugs which act in arterial vascular beds. Anesthetized adult male Wistar rats underwent to right femoral artery and vein cannulation for hemodynamic recordings and infusion of drugs. Doppler flow probes were placed around the left renal artery and vein, and left femoral artery and vein to evaluate the changes in flood flow. Phenylephrine (PHE) injection (α 1 -adrenergic receptor agonist) elicited vasoconstriction in all arteries and veins. Intravenous prazosin (PZS) (1mg/kg, α 1 -adrenergic receptor blocker) caused renal artery vasodilation, but not in the other beds. Vasoconstrictor effect of PHE was abolished by PZS in all vascular beds, except in femoral vein. Phentolamine (PTL) injection (1mg/kg, α 1 /α 2 -adrenergic receptor blocker) produced renal artery vasodilation with no change in other beds. After PTL, the vasoconstriction evoked by PHE was abolished in all vascular beds. Sodium Nitroprusside (SNP), a nitric oxide donor, elicited vasodilation in all beds, and after PTL but not post PZS injection, SNP enhanced the vasodilatory effect in femoral vein. Our findings suggest that the vasoconstriction in renal and femoral veins is mediated by different subtypes of α-adrenoceptors. The nitric oxide-dependent vasodilation in femoral vein enhances when α 2 -adrenoceptors are not under stimulation, but not in the other vascular beds investigated. Copyright © 2017 Elsevier Inc. All rights reserved.

Failure to demonstrate that playing violent video games diminishes prosocial behavior.

Directory of Open Access Journals (Sweden)

Morgan J Tear

Full Text Available BACKGROUND: Past research has found that playing a classic prosocial video game resulted in heightened prosocial behavior when compared to a control group, whereas playing a classic violent video game had no effect. Given purported links between violent video games and poor social behavior, this result is surprising. Here our aim was to assess whether this finding may be due to the specific games used. That is, modern games are experienced differently from classic games (more immersion in virtual environments, more connection with characters, etc. and it may be that playing violent video games impacts prosocial behavior only when contemporary versions are used. METHODS AND FINDINGS: Experiments 1 and 2 explored the effects of playing contemporary violent, non-violent, and prosocial video games on prosocial behavior, as measured by the pen-drop task. We found that slight contextual changes in the delivery of the pen-drop task led to different rates of helping but that the type of game played had little effect. Experiment 3 explored this further by using classic games. Again, we found no effect. CONCLUSIONS: We failed to find evidence that playing video games affects prosocial behavior. Research on the effects of video game play is of significant public interest. It is therefore important that speculation be rigorously tested and findings replicated. Here we fail to substantiate conjecture that playing contemporary violent video games will lead to diminished prosocial behavior.

Failure to Demonstrate That Playing Violent Video Games Diminishes Prosocial Behavior

Science.gov (United States)

Tear, Morgan J.; Nielsen, Mark

2013-01-01

Background Past research has found that playing a classic prosocial video game resulted in heightened prosocial behavior when compared to a control group, whereas playing a classic violent video game had no effect. Given purported links between violent video games and poor social behavior, this result is surprising. Here our aim was to assess whether this finding may be due to the specific games used. That is, modern games are experienced differently from classic games (more immersion in virtual environments, more connection with characters, etc.) and it may be that playing violent video games impacts prosocial behavior only when contemporary versions are used. Methods and Findings Experiments 1 and 2 explored the effects of playing contemporary violent, non-violent, and prosocial video games on prosocial behavior, as measured by the pen-drop task. We found that slight contextual changes in the delivery of the pen-drop task led to different rates of helping but that the type of game played had little effect. Experiment 3 explored this further by using classic games. Again, we found no effect. Conclusions We failed to find evidence that playing video games affects prosocial behavior. Research on the effects of video game play is of significant public interest. It is therefore important that speculation be rigorously tested and findings replicated. Here we fail to substantiate conjecture that playing contemporary violent video games will lead to diminished prosocial behavior. PMID:23844191

Assessment of endothelium: Dependent vasodilation with a non-invasive method in patients with preeclampsia compared to normotensive pregnant women

Directory of Open Access Journals (Sweden)

Seyedeh Zahra Allameh

2014-01-01

Full Text Available Background: To assess the endothelial function via noninvasive method, in pregnant women with preeclampsia compared to to normotensive pregnant women. Materials and Methods: Brachial artery diameter was measured via ultrasound, in 28 women with preeclampcia in case group and normotensive pregnant women in control group, at rest, after inflation of sphygmomanometer cuff up to 250-300 mmHg, immediately after deflation of the cuff, 60-90 minutes later and 5 min after administration of sublingual trinitroglycerin (TNG. Results of these measurements as well as demographic characteristics of participants in both groups were recorded in special forms. Data were analyzed via Statistical Package for Social Sciences (SPSS version 16, using t-test and repeated measures analysis of variance (ANOVA. P-value < 0.05 was considered statistically significant. The results were presented as mean ± standard deviation (SD. Results: The mean of brachial artery diameter at rest in the case and control groups was 4.49 ± 0.39 and 4.08 ± 0.38 mm, respectively (P = 0.1. Also the results showed that the brachial artery diameter, immediately after deflation of the cuff, was 4.84 ± 0.4 and 4.37 ± 0.30 mm in the case and control groups (P < 0.001, respectively. The mean brachial artery diameter, 60-90 s after deflation of the cuff, was 4.82 ± 0.41 and 4.42 ± 0.38 mm in the case and control groups (P < 0.00, respectively. The brachial artery diameter, 5 min after sublingual NO administration, was 4.95 ± 0.6 and 4.40 ± 0.45 mm in case and control groups (P < 0.001, respectively. Applying of repeated measures ANOVA showed that the mean difference between case and control groups was statistically significant (P < 0.001. Conclusion: Current study concluded that there is no difference in endothelium-dependent vasodilation between women with preeclampsia and pregnant women with normal blood pressure.

Brazilian uranium reserves

International Nuclear Information System (INIS)

Marques, J.P.M.

1981-01-01

Due to a growing demand of electric power to support Brasil's development, the use of nuclear energy will be indispensable. The nuclear fuel cycle for the production of energy, starts with the uranium exploration. The work performed in this field led to the discovery of several deposits in the country, which to-date totalize a reserve of 236,300t of U 308 , ranking Brazil in the 6th place among the nations of the western world holding uranium reserves. (Author) [pt

The Fate of Aspen in a World with Diminishing Snowpacks

Science.gov (United States)

Kavanagh, K.; Link, T. E.; Seyfried, M. S.; Kemp, K. B.

2010-12-01

Aspen (Populus tremuloides) productivity is tightly coupled with soil moisture. In the mountainous regions of the western USA, annual replenishment of soil moisture commonly occurs during snowmelt. Therefore, snow pack depth and duration can play an important role in sustaining aspen productivity. The presence of almost 50 years of detailed climate data across an elevational transect in the Reynolds Creek Experimental Watershed (RCEW) in southwestern Idaho offers a novel opportunity to better understand the role of shifting precipitation patterns on aspen productivity. Over the past 50 years, the proportion of the precipitation falling in the form of snow decreased by almost a factor of 2 at mid to low elevations in the RCEW, coupled with a roughly four week advance of snow ablation, and decline of large snow drifts that release moisture into the early summer. Results from growth ring increment, stable isotope analysis, sapflux and a process model (Biome BGC), will be used to determine the impact of shifting precipitation patterns on tree productivity along this transect over the past 50 years. Aspen trees located on moist microsites continue to transpire water and maintain high stomatal conductance 21 days later in the growing season relative to individuals on drier microsites. Predictions of net primary productivity (NPP) in aspen are very sensitive to precipitation patterns. NPP becomes negative as early as day 183 (90 days post budbreak) for years with little winter and spring precipitation whereas, in years with ample winter and spring precipitation, NPP remains positive until day 260 when leaf fall occurs. These results give unique insight into the conditions that deciduous tree species will encounter in a warming climate where snow water equivalent continues to diminish and soil moisture declines soon after budbreak occurs.

Fractional Reserve in Banking System

OpenAIRE

Valkonen, Maria

2016-01-01

This thesis is aimed to provide understanding of the role of the fractional reserve in the mod-ern banking system worldwide and particularly in Finland. The fractional reserve banking is used worldwide, but the benefits of this system are very disputable. On the one hand, experts say that the fractional reserve is a necessary instrument for the normal business and profit making. On the other hand, sceptics openly criticize the fractional reserve system and blame it for fiat money (money n...

Pregnancy Augments VEGF-Stimulated In Vitro Angiogenesis and Vasodilator (NO and H2S) Production in Human Uterine Artery Endothelial Cells.

Science.gov (United States)

Zhang, Hong-Hai; Chen, Jennifer C; Sheibani, Lili; Lechuga, Thomas J; Chen, Dong-Bao

2017-07-01

Augmented uterine artery (UA) production of vasodilators, including nitric oxide (NO) and hydrogen sulfide (H2S), has been implicated in pregnancy-associated and agonist-stimulated rise in uterine blood flow that is rate-limiting to pregnancy health. Developing a human UA endothelial cell (hUAEC) culture model from main UAs of nonpregnant (NP) and pregnant (P) women for testing a hypothesis that pregnancy augments endothelial NO and H2S production and endothelial reactivity to vascular endothelial growth factor (VEGF). Main UAs from NP and P women were used for developing hUAEC culture models. Comparisons were made between NP- and P-hUAECs in in vitro angiogenesis, activation of cell signaling, expression of endothelial NO synthase (eNOS) and H2S-producing enzymes cystathionine β-synthase (CBS) and cystathionine γ-lyase, and NO/H2S production upon VEGF stimulation. NP- and P-hUAECs displayed a typical cobblestone-like shape in culture and acetylated low-density lipoprotein uptake, stained positively for endothelial and negatively for smooth muscle markers, maintained key signaling proteins during passage, and had statistically significant greater eNOS and CBS proteins in P- vs NP-hUAECs. Treatment with VEGF stimulated in vitro angiogenesis and eNOS protein and NO production only in P-hUEACs and more robust cell signaling in P- vs NP-hUAECs. VEGF stimulated CBS protein expression, accounting for VEGF-stimulated H2S production in hUAECs. Comparisons between NP- and P-hUAECs reveal that pregnancy augments VEGF-stimulated in vitro angiogenesis and NO/H2S production in hUAECs, showing that the newly established hUAEC model provides a critical in vitro tool for understanding human uterine hemodynamics. Copyright © 2017 Endocrine Society

Relationship between regional myocardial blood flow and thallium-201 distribution in the presence of coronary artery stenosis and dipyridamole-induced vasodilation

International Nuclear Information System (INIS)

Mays, A.E. Jr.; Cobb, F.R.

1984-01-01

This study assesses the relationship between the distribution of thallium-201 and myocardial blood flow during coronary vasodilation induced by intravenous dipyridamole in canine models of partial and complete coronary artery stenosis. 10 dogs were chronically instrumented with catheters in the left atrium and aorta and with a balloon occluder and electromagnetic flow probe on the proximal left circumflex coronary artery. Regional myocardial blood flow was measured during control conditions with radioisotope-labeled microspheres, and the phasic reactive hyperemic response to a 20-s transient occlusion was then recorded. Dipyridamole was then infused intravenously until phasic coronary blood flow increased to match peak hyperemic values. The left circumflex coronary artery was either partially occluded to reduce phasic blood flow to control values (group 1) or it was completely occluded (group 2), and thallium-201 and a second microsphere label were injected. 5 min later, the animals were sacrificed, the left ventricle was sectioned into 1-2-g samples, and thallium-201 activity and regional myocardial blood flow were measured. Curvilinear regression analyses between thallium-201 localization and myocardial blood flow during dipyridamole infusion demonstrated a slightly better fit to a second- as compared with a first-order model, indicating a slight roll-off of thallium activity as myocardial blood flow increases. During the dipyridamole infusion, the increases in phasic blood flow, the distributions of regional myocardial blood flow, and the relationships between thallium-201 localization and regional blood flow were comparable to values previously observed in exercising dogs with similar occlusions. These data provide basic validation that supports the use of intravenous dipyridamole and thallium-201 as an alternative to exercise stress and thallium-201 for evaluating the effects of coronary occlusive lesions on the distribution of regional myocardial blood flow

Micro-level stochastic loss reserving

NARCIS (Netherlands)

Antonio, K.; Plat, R.

2010-01-01

To meet future liabilities general insurance companies will set-up reserves. Predicting future cash-flows is essential in this process. Actuarial loss reserving methods will help them to do this in a sound way. The last decennium a vast literature about stochastic loss reserving for the general

No Spearman’s Law of Diminishing Returns for the working memory and intelligence relationship

Directory of Open Access Journals (Sweden)

Kroczek Bartłomiej

2016-04-01

Full Text Available Spearman’s Law of Diminishing Returns (SLODR holds that correlation between general (g/fluid (Gf intelligence factor and other cognitive abilities weakens with increasing ability level. Thus, cognitive processing in low ability people is most strongly saturated by g/Gf, whereas processing in high ability people depends less on g/Gf. Numerous studies demonstrated that low g is more strongly correlated with crystallized intelligence/creativity/processing speed than is high g, however no study tested an analogous effect in the case of working memory (WM. Our aim was to investigate SLODR for the relationship between Gf and WM capacity, using a large data set from our own previous studies. We tested alternative regression models separately for three types of WM tasks that tapped short-term memory storage, attention control, and relational integration, respectively. No significant SLODR effect was found for any of these tasks. Each task shared with Gf virtually the same amount of variance in the case of low- and high-ability people. This result suggests that Gf and WM rely on one and the same (neurocognitive mechanism.

Calculation program development for spinning reserve

International Nuclear Information System (INIS)

1979-01-01

This study is about optimal holding of spinning reserve and optimal operation for it. It deals with the purpose and contents of the study, introduction of the spinning reserve electricity, speciality of the spinning reserve power, the result of calculation, analysis for limited method of optimum load, calculation of requirement for spinning reserve, analysis on measurement of system stability with summary, purpose of the analysis, cause of impact of the accident, basics on measurement of spinning reserve and conclusion. It has the reference on explanation for design of spinning reserve power program and using and trend about spinning reserve power in Korea.

Assessing reserve-building pursuits and person characteristics: psychometric validation of the Reserve-Building Measure.

Science.gov (United States)

Schwartz, Carolyn E; Michael, Wesley; Zhang, Jie; Rapkin, Bruce D; Sprangers, Mirjam A G

2018-02-01

A growing body of research suggests that regularly engaging in stimulating activities across multiple domains-physical, cultural, intellectual, communal, and spiritual-builds resilience. This project investigated the psychometric characteristics of the DeltaQuest Reserve-Building Measure for use in prospective research. The study included Rare Patient Voice panel participants. The web-based survey included the Reserve-Building Measure with one-week re-test, measures of quality of life (QOL) and well-being (PROMIS General Health; NeuroQOL Cognitive Function and Positive Affect & Well-Being short-forms; Ryff Environmental Mastery subscale); and the Big Five Inventory-10 personality measure. Classical test theory and item response theory (IRT) analyses investigated psychometric characteristics of the Reserve-Building Measure. This North American sample (n = 592) included both patients and caregivers [mean age = 44, SD 19)]. Psychometric analyses revealed distinct subscales measuring current reserve-building activities (Active in the World, Games, Outdoors, Creative, Religious/Spiritual, Exercise, Inner Life, Shopping/Cooking, Passive Media Consumption,), past reserve-building activities (Childhood Activities, Achievement), and reserve-related person-factors (Perseverance, Current and Past Social Support, and Work Value). Test-retest stability (n = 101) was moderately high for 11 of 15 subscales (ICC range 0.78-0.99); four were below 0.59 indicating a need for further refinement. IRT analyses supported the item functioning of all subscales. Correlational analyses suggest the measure's subscales tap distinct constructs (range r = 0.11-0.46) which are not redundant with QOL, well-being, or personality (range r = 0.11-0.48). The Reserve-Building Measure provides a measure of activities and person-factors related to reserve that may potentially be useful in prospective research.

Introducing optional reserve ratios in Hungary

OpenAIRE

Lóránt Varga

2010-01-01

As of the reserve maintenance period commencing in November 2010, Hungarian credit institutions will be free to decide whether to apply the previously valid 2% reserve ratio, or to apply a higher mandatory reserve ratio. Credit institutions required to hold reserves may select from reserve ratios of 2, 3, 4 and 5%, and may change their decision on a semi-annual basis. In line with the international best practice, the purpose of the MNB’s reserve requirement system is to support credit institu...

Evaluation on diminishing effects of DNA damaging potential by humic substances using the bacillus subtilis rec-assay; Karekusakin rec-assay wo mochiita fuminsan ni yoru DNA sonshosei kaizen koka no kento

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, H.; Takigami, H.; Shimizu, Y.; Matsui, S. [Kyoto University, Kyoto (Japan). Faculty of Engineering

1998-05-22

Antimutagenic effect of humic substances has been reported by various investigators. In this research, the diminishing effect of DNA damaging toxicity by humic acid was evaluated for the influent and effluent of activated sludge tank receiving municipal wastewater and several DNA damaging chemicals (e.g., pyrene, 1-aminopyrene and benzo(a)pyrene) using Bacillus subtilis rec-assay. The diminishing effect was not apparent for influent but observed in the effluent. Among the DNA damaging chemicals, the DNA toxicity was effectively suppressed by humic acid for pyrene and benzo(a)pyrene. However, the effect was relatively smaller for 1-aminopyrene. 19 refs., 6 figs., 6 tabs.

Interaction of calcitonin gene related peptide (CGRP) and substance P (SP) in human skin.

Science.gov (United States)

Schlereth, Tanja; Schukraft, Jonas; Krämer-Best, Heidrun H; Geber, Christian; Ackermann, Tatiana; Birklein, Frank

2016-10-01

Calcitonin gene related peptide (CGRP) and substance P (SP) are neuropeptides that are simultaneously released from nociceptive C-fibers. CGRP is a potent vasodilator, inducing a long-lasting increase in superficial skin blood flow, whereas SP induces only a brief vasodilation but a significant plasma extravasation. CGRP and SP may play important roles in the pathophysiology of various pain states but little is known about their interaction. Different concentrations of SP (ranging from 10 -5 M to 10 -9 M) were applied to the volar forearm of 24 healthy subjects via dermal microdialysis. SP was applied either alone or in combination with CGRP10 -9 M and CGRP 10 -6 M. As expected, SP induced a transient increase in skin blood flow that decayed shortly after application. This transient blood flow peak was blunted with co-application of CGRP 10 -9 M and inhibited with co-application of CGRP10 -6 M. SP alone induced plasma protein extravasation (PPE). However, when CGRP10 -6 M was added, the PPE significantly increased. Our results demonstrate a complex interaction of the neuropeptides CGRP and SP. CGRP10 -6 M prevented SP-induced early vasodilation but augmented SP-induced PPE. These interactions might explain why vascular symptoms in chronic pain can differ strikingly between individuals. Copyright © 2016 Elsevier Ltd. All rights reserved.

Phase coherence of 0.1 Hz microvascular tone oscillations during the local heating

Science.gov (United States)

Mizeva, I. A.

2017-06-01

The origin of the mechanisms of blood flow oscillations at low frequencies is discussed. It is known that even isolated arteriole demonstrates oscillations with the frequency close to 0.1 Hz, which is caused by the synchronous activity of myocyte cells. On the other hand, oscillations with close frequency are found in the heart rate, which are associated with quite different mechanism. The main purpose of this work is to study phase coherence of the blood flow oscillations in the peripheral vessels under basal and perturbed conditions. Local heating which locally influences the microvascular tone, as one of currently elucidated in sufficient detail physiological test, was chosen. During such provocation blood flow though the small vessels significantly increases because of vasodilation induced by the local synthesis of nitric oxide. In the first part of the paper microvascular response to the local test is quantified in healthy and pathological conditions of diabetes mellitus type 1. It is obtained that regardless of the pathology, subjects with high basal perfusion had lower reserve for vasodilation, which can be caused by the low elasticity of microvascular structure. Further synchronization of pulsations of the heated and undisturbed skin was evaluated on the base of wavelet phase coherency analysis. Being highly synchronised in basal conditions 0.1 Hz pulsations became more independent during heating, especially during NO-mediated vasodilation.

A Century in Reserve and Beyond

National Research Council Canada - National Science Library

Monagle, James P

2008-01-01

... Reserve, this Strategy Research Project (SRP) describes the role of the Army Reserve from its beginning as a reserve corps of medical doctors to that of a strategic reserve force, and then to its current operational role...

Reserve selection with land market feedbacks.

Science.gov (United States)

Butsic, Van; Lewis, David J; Radeloff, Volker C

2013-01-15

How to best site reserves is a leading question for conservation biologists. Recently, reserve selection has emphasized efficient conservation: maximizing conservation goals given the reality of limited conservation budgets, and this work indicates that land market can potentially undermine the conservation benefits of reserves by increasing property values and development probabilities near reserves. Here we propose a reserve selection methodology which optimizes conservation given both a budget constraint and land market feedbacks by using a combination of econometric models along with stochastic dynamic programming. We show that amenity based feedbacks can be accounted for in optimal reserve selection by choosing property price and land development models which exogenously estimate the effects of reserve establishment. In our empirical example, we use previously estimated models of land development and property prices to select parcels to maximize coarse woody debris along 16 lakes in Vilas County, WI, USA. Using each lake as an independent experiment, we find that including land market feedbacks in the reserve selection algorithm has only small effects on conservation efficacy. Likewise, we find that in our setting heuristic (minloss and maxgain) algorithms perform nearly as well as the optimal selection strategy. We emphasize that land market feedbacks can be included in optimal reserve selection; the extent to which this improves reserve placement will likely vary across landscapes. Copyright © 2012 Elsevier Ltd. All rights reserved.

Lithium reserves and resources

International Nuclear Information System (INIS)

Evans, R.K.

1978-01-01

As a result of accelerating research efforts in the fields of secondary batteries and thermonuclear power generation, concern has been expressed in certain quarters regarding the availability, in sufficient quantities, of lithium. As part of a recent study by the National Research Council on behalf of the Energy Research and Development Administration, a subpanel was formed to consider the outlook for lithium. Principal areas of concern were reserves, resources and the 'surplus' available for energy applications after allowing for the growth in current lithium applications. Reserves and resources were categorized into four classes ranging from fully proved reserves to resources which are probably dependent upon the marketing of co-products to become economically attractive. Because of the proprietary nature of data on beneficiation and processing recoveries, the tonnages of available lithium are expressed in terms of plant feed. However, highly conservative assumptions have been made concerning mining recoveries and these go a considerable way to accounting for total losses. Western World reserves and resources of all classes are estimated at 10.6 million tonnes Li of which 3.5 million tonnes Li are located in the United States. Current United States capacity, virtually equivalent to Western World capacity, is 4700 tonnes Li and production in 1976 approximated to 3500 tonnes Li. Production for current applications is expected to grow to approx. 10,000 tonnes in year 2000 and 13,000 tonnes a decade later. The massive excess of reserves and resources over that necessary to support conventional requirements has limited the amount of justifiable exploration expenditures; on the last occasion, there was a a major increase in demand (by the USAEA) reserves and capacity were increased rapidly. There are no foreseeable reasons why this shouldn't happen again when the need is clear. (author)

Rat whisker movement after facial nerve lesion: evidence for autonomic contraction of skeletal muscle.

Science.gov (United States)

Heaton, James T; Sheu, Shu Hsien; Hohman, Marc H; Knox, Christopher J; Weinberg, Julie S; Kleiss, Ingrid J; Hadlock, Tessa A

2014-04-18

Vibrissal whisking is often employed to track facial nerve regeneration in rats; however, we have observed similar degrees of whisking recovery after facial nerve transection with or without repair. We hypothesized that the source of non-facial nerve-mediated whisker movement after chronic denervation was from autonomic, cholinergic axons traveling within the infraorbital branch of the trigeminal nerve (ION). Rats underwent unilateral facial nerve transection with repair (N=7) or resection without repair (N=11). Post-operative whisking amplitude was measured weekly across 10weeks, and during intraoperative stimulation of the ION and facial nerves at ⩾18weeks. Whisking was also measured after subsequent ION transection (N=6) or pharmacologic blocking of the autonomic ganglia using hexamethonium (N=3), and after snout cooling intended to elicit a vasodilation reflex (N=3). Whisking recovered more quickly and with greater amplitude in rats that underwent facial nerve repair compared to resection (Pfacial-nerve-mediated whisking was elicited by electrical stimulation of the ION, temporarily diminished following hexamethonium injection, abolished by transection of the ION, and rapidly and significantly (Pfacial nerve resection. This study provides the first behavioral and anatomical evidence of spontaneous autonomic innervation of skeletal muscle after motor nerve lesion, which not only has implications for interpreting facial nerve reinnervation results, but also calls into question whether autonomic-mediated innervation of striated muscle occurs naturally in other forms of neuropathy. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

24 CFR 891.605 - Replacement reserve.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Replacement reserve. 891.605... 8 Assistance § 891.605 Replacement reserve. (a) Establishment of reserve. The Borrower shall establish and maintain a replacement reserve to aid in funding extraordinary maintenance, and repair and...

24 CFR 891.405 - Replacement reserve.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Replacement reserve. 891.405....405 Replacement reserve. (a) Establishment of reserve. The Owner shall establish and maintain a replacement reserve to aid in funding extraordinary maintenance and repair and replacement of capital items...

A change will do us good: threats diminish typical preferences for male leaders.

Science.gov (United States)

Brown, Elizabeth R; Diekman, Amanda B; Schneider, Monica C

2011-07-01

The current research explores role congruity processes from a new vantage point by investigating how the need for change might shift gender-based leadership preferences. According to role congruity theory, favorability toward leaders results from alignment between what is desired in a leadership role and the characteristics stereotypically ascribed to the leader. Generally speaking, these processes lead to baseline preferences for male over female leaders. In this research, the authors propose that a shift in gender-based leadership preferences will emerge under conditions of threat. Because the psychological experience of threat signals a need for change, individuals will favor candidates who represent new directions in leadership rather than consistency with past directions in leadership. Specifically, they find that threat evokes an implicit preference for change over stability (Experiment 1) and gender stereotypes align women with change but men with stability (Experiments 2a and 2b). Consequently, the typical preference for male leaders is diminished, or even reversed, under threat (Experiments 3 and 4). Moreover, the shift away from typical gender-based leadership preferences occurs especially among individuals who highly legitimize the sociopolitical system (Experiment 4), suggesting that these preference shifts might serve to protect the underlying system. © 2011 by the Society for Personality and Social Psychology, Inc

Reserves Represented by Random Walks

International Nuclear Information System (INIS)

Filipe, J A; Ferreira, M A M; Andrade, M

2012-01-01

The reserves problem is studied through models based on Random Walks. Random walks are a classical particular case in the analysis of stochastic processes. They do not appear only to study reserves evolution models. They are also used to build more complex systems and as analysis instruments, in a theoretical feature, of other kind of systems. In this work by studying the reserves, the main objective is to see and guarantee that pensions funds get sustainable. Being the use of these models considering this goal a classical approach in the study of pensions funds, this work concluded about the problematic of reserves. A concrete example is presented.

Metabolic control of muscle blood flow during exercise in humans

DEFF Research Database (Denmark)

Boushel, Robert Christopher

2003-01-01

that combined blockade of NOS and PGI2, and NOS and cytochrome P450, both attenuate exercise-induced hyperemia in humans. Combined vasodilator blockade studies offer the potential to uncover important interactions and compensatory vasodilator responses. The signaling pathways that link metabolic events evoked...... to exert control of muscle vasodilation. Adenosine, nitric oxide (NO), prostacyclin (PGI2), and endothelial-derived hyperpolarization factor (EDHF) are possible mediators of muscle vasodilation during exercise. In humans, adenosine has been shown to contribute to functional hyperemia as blood flow...... by muscle contraction to vasodilatory signals in the local vascular bed remains an important area of study....

Matrine inhibits the adhesion and migration of BCG823 gastric cancer cells by affecting the structure and function of the vasodilator-stimulated phosphoprotein (VASP).

Science.gov (United States)

Zhang, Jing-wei; Su, Ke; Shi, Wen-tao; Wang, Ying; Hu, Peng-chao; Wang, Yang; Wei, Lei; Xiang, Jin; Yang, Fang

2013-08-01

Vasodilator-stimulated phosphoprotein (VASP) expression is upregulated in human cancers and correlates with more invasive advanced tumor stages. The aim of this study was to elucidate the mechanisms by which matrine, an alkaloid derived from Sophora species plants, acted on the VASP protein in human gastric cancer cells in vitro. VASP was expressed and purified. Intrinsic fluorescence spectroscopy was used to study the binding of matrine to VASP. CD spectroscopy was used to examine the changes in the VASP protein secondary structure. Human gastric carcinoma cell line BGC823 was tested. Scratch wound and cell adhesion assays were used to detect the cell migration and adhesion, respectively. Real-time PCR and Western blotting assays were used to measure mRNA and protein expression of VASP. In the fluorescence assay, the dissociation constant for binding of matrine to VASP protein was 0.86 mmol/L, thus the direct binding between the two molecules was weak. However, matrine (50 μg/mL) caused obvious change in the secondary structure of VASP protein shown in CD spectrum. Treatments of BGC823 cells with matrine (50 μg/mL) significantly inhibited the cell migration and adhesion. The alkaloid changed the subcellular distribution of VASP and formation of actin stress fibers in BGC823 cells. The alkaloid caused small but statistically significant decreases in VASP protein expression and phosphorylation, but had no significant effect on VASP mRNA expression. Matrine modulates the structure, subcellular distribution, expression and phosphorylation of VASP in human gastric cancer cells, thus inhibiting the cancer cell adhesion and migration.

[Vertical distribution and community diversity of butterflies in Yaoluoping National Nature Reserve, Anhui, China].

Science.gov (United States)

Wang, Song; Bao, Fang-yin; Mei, Bai-mao; Ding, Shi-chao

2009-09-01

By the methods of fixed point, line intercept, and random investigation, the vertical distribution and community diversity of butterflies in Yaoluoping National Nature Reserve were investigated from 2005 to 2008. A total of 3681 specimen were collected, belonging to 111 species, 69 genera, and 10 families, among which, Nymphalidae had the higher species number, individual's number, and diversity index than the other families. The butterflies in the study area were a mixture of Oriental and Palaearetic species, with the Oriental species diminished gradually and the Palaearetic components increased gradually with increasing altitude. Among the three vertical zones ( 1200 m in elevation), that of 800-1200 m had the most abundant species of butterflies; and among the six habitat types (deciduous broad-leaved forest, evergreen conifer forest, conifer-broad leaf mixed forest, bush and secondary forest, farmland, and residential area), bush and secondary forest had the higher species number, individual's number, and diversity index of butterflies, while farmland had the lowest diversity index. The similarity coefficient of butterfly species between the habitats was mainly dependent on vegetation type, i.e., the more the difference of vegetation type, the lesser the species similarity coefficient between the habitats, which was the highest (0.61) between conifer-broad leaf mixed forest and bush and secondary forest, and the lowest (0. 20) between evergreen conifer forest and bush and secondary forest.

Cold-induced vasodilation during single digit immersion in 0°C and 8°C water in men and women.

Directory of Open Access Journals (Sweden)

Christopher James Tyler

Full Text Available The present study compared the thermal responses of the finger to 0 and 8°C water immersion, two commonly used temperatures for cold-induced vasodilation (CIVD research. On two separate and counterbalanced occasions 15 male and 15 female participants immersed their index finger in 20°C water for 5 min followed by either 0 or 8°C water for 30 min. Skin temperature, cardiovascular and perceptual data were recorded. Secondary analyses were performed between sexes and comparing 0.5, 1 and 4°C CIVD amplitude thresholds. With a 0.5°C threshold, CIVD waves were more prevalent in 8°C (2 (1-3 than in 0°C (1.5 (0-3, but the amplitude was lower (4.0 ± 2.3 v 9.2 ± 4.0°C. Mean, minimum and maximum finger temperatures were lower in 0°C during the 30 min immersion, and CIVD onset and peak time occurred later in 0°C. Thermal sensation was lower and pain sensation was higher in 0°C. There were no differences between males and females in any of the physiological or CIVD data with the exception of SBP, which was higher in males. Females reported feeling higher thermal sensations in 8°C and lower pain sensations in 0°C and 8°C compared to males. Fewer CIVD responses were observed when using a 4°C (1 (0-3 threshold to quantify a CIVD wave compared to using a 1°C (2 (0-3 or 0.5°C (2 (0-3 amplitude. In conclusion, both 0 and 8 °C can elicit CIVD but 8°C may be more suitable when looking to optimise the number of CIVD waves while minimising participant discomfort. The CIVD response to water immersion does not appear to be influenced by sex. Researchers should consider the amplitude threshold that was used to determine a CIVD wave when interpreting previous data.

Improved Effectiveness of Reserve Forces During Reserve Duty Training.

Science.gov (United States)

Treadaway, Harry H.

The problem areas of motivation, job enrichment, recruiting, and retention are addressed from the viewpoint of the behavioral scientist. Special attention is given to relating job enrichment and motivation techniques, as successfully demonstrated in industry, to the United State Army Reserve. Research method utilized was a literature review…

Amiodarona causa vasodilatação dependente do endotélio em artérias coronárias caninas Amiodarone causes endothelium-dependent vasodilation in canine coronary arteries

Directory of Open Access Journals (Sweden)

Alfredo José Rodrigues

2005-03-01

Full Text Available OBJETIVO: Avaliar os efeitos vasodilatadores da amiodarona em artérias coronárias caninas empregando soluções de amiodarona dissolvida em polisorbato 80 ou em água. MÉTODOS: Anéis de artéria coronária, com e sem o endotélio íntegro, foram imersos em solução de krebs e conectadas a um transdutor para aferição de força isométrica promovida por contração vascular. As artérias foram expostas a concentrações crescentes de polisorbato 80, amiodarona dissolvida em água, amiodarona dissolvida em polisorbato 80 e uma apresentação comercial da amiodarona (Cordarone®. Os experimentos foram conduzidos na presença e na ausência dos seguintes bloqueadores enzimáticos: apenas indometacina, Nômega-nitro-L-arginina associada à indometacina e apenas Nômega-nitro-L-arginina. RESULTADOS: O polisorbato 80 causou pequeno relaxamento não dependente do endotélio. O Cordarone®, a amiodarona dissolvida em água e em polisorbato 80 promoveram relaxamento dependente do endotélio, que foi de maior magnitude para a amiodarona dissolvida em polisorbato e para o Cordarone®. Apenas a associação de indometacina com a Nômega-nitro-L-arginina foi capaz de abolir o relaxamento dependente do endotélio provocado pela amiodarona dissolvida em polisorbato 80. CONCLUSÃO: Os resultados obtidos indicam que a vasodilatação promovida pela amiodarona em artérias coronárias caninas é causada principalmente pela estimulação da liberação de óxido nítrico e fatores endoteliais relaxantes dependentes das ciclo-oxigenases.OBJECTIVE: To assess the vasodilating effects of amiodarone on canine coronary arteries by using solutions of amiodarone dissolved in polysorbate 80 or water. METHODS: Rings of coronary arteries, with or without intact endothelium, were immersed in Krebs solution and connected to a transducer for measuring the isometric force promoted by a vascular contraction. The arteries were exposed to increasing concentrations of

FEATURES OF PERFECT AND IMPERFECT RESERVES AND RESERVE FUNDS WITHIN THE FEDERAL BUDGET OF THE RUSSIAN FEDERATION

Directory of Open Access Journals (Sweden)

Tatyana P. Lomakina

2018-03-01

Full Text Available During the past two years (2016–2017, the mass media was engaged in tense discussion about the status and flow of funds within the two reserves – the Reserve Fund of the Russian Federation and the National Welfare Fund. The Reserve Fund of the Russian Federation aroused especial worries among the experts. Its funds rapidly declined and by December 2017 they were fully used to cover the deficit of the domestic budget. In accordance with the law “On Amendments to the Budget Code of the Russian Federation in the Use of Oil and Gas Revenues of the Federal Budget,” from February 1, 2018, the Reserve Fund of the Russian Federation will cease to exist. For financial theory, this fact can serve as an illustration of the process of forming the foundations of budgetary financial security, their change over time, circumstances and options the government can take to modify them. At the same time, there are other types of financial resources within the federal budget. Their diversity necessitates their classification in order to identify groups and types with similar characteristics. However, in financial theory, many types of reserves are not described in detail, and some are not described at all. This article introduces the concepts of “perfect” and “imperfect” reserves, for their characterization as part of the federal budget. The Russian Reserve Fund and the National Welfare Fund (Sovereign Funds are the examples of perfect financial reserves. Imperfect reserves comprise a large group of reserve funds that are included in the federal budget, for example, the Reserve Fund of the President of the Russian Federation and the Reserve Fund of the Government of the Russian Federation, the Reserve Fund of the Government of the Russian Federation for the prevention and control of emergencies and impact of natural disasters. The introduction of new typological features largely clarifies the situation with increased attention to one type of reserves

Reserve valuation in electric power systems

Science.gov (United States)

Ruiz, Pablo Ariel

Operational reliability is provided in part by scheduling capacity in excess of the load forecast. This reserve capacity balances the uncertain power demand with the supply in real time and provides for equipment outages. Traditionally, reserve scheduling has been ensured by enforcing reserve requirements in the operations planning. An alternate approach is to employ a stochastic formulation, which allows the explicit modeling of the sources of uncertainty. This thesis compares stochastic and reserve methods and evaluates the benefits of a combined approach for the efficient management of uncertainty in the unit commitment problem. Numerical studies show that the unit commitment solutions obtained for the combined approach are robust and superior with respect to the traditional approach. These robust solutions are especially valuable in areas with a high proportion of wind power, as their built-in flexibility allows the dispatch of practically all the available wind power while minimizing the costs of operation. The scheduled reserve has an economic value since it reduces the outage costs. In several electricity markets, reserve demand functions have been implemented to take into account the value of reserve in the market clearing process. These often take the form of a step-down function at the reserve requirement level, and as such they may not appropriately represent the reserve value. The value of reserve is impacted by the reliability, dynamic and stochastic characteristics of system components, the system operation policies, and the economic aspects such as the risk preferences of the demand. In this thesis, these aspects are taken into account to approximate the reserve value and construct reserve demand functions. Illustrative examples show that the demand functions constructed have similarities with those implemented in some markets.

Strategic Petroleum Reserve Site Environmental Report for calendar year 1994

International Nuclear Information System (INIS)

1995-01-01

The purpose of this Site Environmental Report (SER) is to characterize site environmental management performance, confirm compliance with environmental standards and requirements, and highlight significant programs and efforts. The SER, provided annually in accordance with Department of Energy DOE Order 5400.1, serves the public by summarizing monitoring data collected to assess how the Strategic Petroleum Reserve (SPR) impacts the environment. This report (SER) provides a balanced synopsis of non-radiological monitoring and regulatory compliance data and affirms that the SPR has been operating within acceptable regulatory limits. Included in this report is a description of each site's environment, an overview of the SPR environmental program, and a recapitulation of special environmental activities and events associated with each SPR site during 1994. Two of these highlights include decommissioning of the Weeks Island facility (disposition of 73 million barrels of crude oil inventory) as well as the degasification of up to 144 million barrels of crude oil inventory at the Bayou Choctaw, Big Hill, Bryan Mound, and West Hackberry facilities. The decision to decommission the Weeks Island facility is a result of diminishing mine integrity from ground water intrusion. Degasifying the crude oil is required to reduce potentially harmful emissions that would occur during oil movements. With regard to still another major environmental action, 43 of the original 84 environmental findings from the 1992 DOE Tiger Team Assessment were closed by the end of 1994. Spills to the environment, another major topic, indicates a positive trend. Total volume of oil spilled in 1994 was only 39 barrels, down from 232 barrels in 1993, and the total volume of brine spilled was only 90 barrels, down from 370 barrels in 1993. The longer term trend for oil and brine spills has declined substantially from 27 in 1990 down to nine in 1994

Naval Petroleum and Oil Shale Reserves

International Nuclear Information System (INIS)

1992-01-01

During fiscal year 1992, the reserves generated $473 million in revenues, a $181 million decrease from the fiscal year 1991 revenues, primarily due to significant decreases in oil and natural gas prices. Total costs were $200 million, resulting in net cash flow of $273 million, compared with $454 million in fiscal year 1991. From 1976 through fiscal year 1992, the Naval Petroleum and Oil Shale Reserves generated more than $15 billion in revenues and a net operating income after costs of $12.5 billion. In fiscal year 1992, production at the Naval Petroleum Reserves at maximum efficient rates yielded 26 million barrels of crude oil, 119 billion cubic feet of natural gas, and 164 million gallons of natural gas liquids. From April to November 1992, senior managers from the Naval Petroleum and Oil Shale Reserves held a series of three workshops in Boulder, Colorado, in order to build a comprehensive Strategic Plan as required by Secretary of Energy Notice 25A-91. Other highlights are presented for the following: Naval Petroleum Reserve No. 1--production achievements, crude oil shipments to the strategic petroleum reserve, horizontal drilling, shallow oil zone gas injection project, environment and safety, and vanpool program; Naval Petroleum Reserve No. 2--new management and operating contractor and exploration drilling; Naval Petroleum Reserve No. 3--steamflood; Naval Oil Shale Reserves--protection program; and Tiger Team environmental assessment of the Naval Petroleum and Oil Shale Reserves in Colorado, Utah, and Wyoming

Public health intervention over four decades for the children in the Australian Capital Territory: Have we reached the point of diminishing returns?

Science.gov (United States)

Sohal, I; Kruger, E; Tennant, M

2017-06-01

Most of the developed world has seen some substantial improvements in the dental health of children over the past four decades owing to advances in service access, fluoride exposure, socio-economic development and improved diets, with the DMFT score of 12 year-olds dropping from well over 10 down to around one. To examine the question of advancing dental health for children even further using the same set of tools as we have to date by asking the question: Have we come to a point of diminishing returns? The study examines the long-term, near optimum settings of the known public dental health variables in the Australian Capital Territory. Despite having the most ideal and persistent dental health optimised situation, there remains underlying dental caries at a severity level of just below 1 DMFT (12 year olds), and over the last decade the rate of diminishing incidence and prevalence of decay has slowed and arguably stopped. This suggests that rather than toiling to eliminate dental decay completely, the focus might usefully be reoriented towards those small known pockets of society with persistent higher levels of disease and looking for new ways to address these difficult clusters, while simultaneously advancing the understanding that a small residual level of decay will always exist in society. Copyright© 2017 Dennis Barber Ltd.

Hydrocarbon Reserves: Abundance or Scarcity

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-01

IFP and the OAPEC jointly organize a regular international seminar dealing with world oil-related problems appearing in the news. For the first time, this seminar has been opened to oil and gas company specialists, service companies, research centers and independents. This year's theme concerns oil and gas reserves: are they abundant or are we headed towards the shortages announced by some experts? This theme is especially topical in that: oil and gas currently meet two thirds of world energy needs and almost completely dominate the transport sector; the reserves declared by the OAPEC countries account for nearly half of world reserves; the price of a barrel of oil went through the roof in 2004; world energy demand is growing fast and alternative sources of energy are far from ready to take over from oil and gas in the next few decades. Since the reserves correspond to the volume it is technically and economically viable to produce, the seminar has, of course, dealt with the technical and economic questions that arise in connection with exploration and production, but it has also considered changes in the geopolitical context. Presentations by the leading companies of the OAPEC countries and by the IFP group were completed by presentation from the International Energy Agency (IEA), the United States Geological Survey (USGS), the IHS Energy Group, Total and Gaz de France. This document gathers the transparencies of the following presentations: Hydrocarbon reserves in OAPEC members countries: current and future (M. Al-Lababidi); Non OAPEC liquid reserves and production forecasts (Y. Mathieu); World oil and gas resources and production outlook (K. Chew); Global investments in the upstream (F. Birol); Total's policy in the oil and gas sector (C. de Margerie); Gaz de France's policy in the oil and gas sector (J. Abiteboul); NOC/IOC's opportunities in OPEC countries (I. Sandrea); Relationships between companies, countries and investors: How they may impact on the growth

Hydrocarbon Reserves: Abundance or Scarcity

International Nuclear Information System (INIS)

2005-01-01

IFP and the OAPEC jointly organize a regular international seminar dealing with world oil-related problems appearing in the news. For the first time, this seminar has been opened to oil and gas company specialists, service companies, research centers and independents. This year's theme concerns oil and gas reserves: are they abundant or are we headed towards the shortages announced by some experts? This theme is especially topical in that: oil and gas currently meet two thirds of world energy needs and almost completely dominate the transport sector; the reserves declared by the OAPEC countries account for nearly half of world reserves; the price of a barrel of oil went through the roof in 2004; world energy demand is growing fast and alternative sources of energy are far from ready to take over from oil and gas in the next few decades. Since the reserves correspond to the volume it is technically and economically viable to produce, the seminar has, of course, dealt with the technical and economic questions that arise in connection with exploration and production, but it has also considered changes in the geopolitical context. Presentations by the leading companies of the OAPEC countries and by the IFP group were completed by presentation from the International Energy Agency (IEA), the United States Geological Survey (USGS), the IHS Energy Group, Total and Gaz de France. This document gathers the transparencies of the following presentations: Hydrocarbon reserves in OAPEC members countries: current and future (M. Al-Lababidi); Non OAPEC liquid reserves and production forecasts (Y. Mathieu); World oil and gas resources and production outlook (K. Chew); Global investments in the upstream (F. Birol); Total's policy in the oil and gas sector (C. de Margerie); Gaz de France's policy in the oil and gas sector (J. Abiteboul); NOC/IOC's opportunities in OPEC countries (I. Sandrea); Relationships between companies, countries and investors: How they may impact on the growth

47 CFR 80.146 - [Reserved

Science.gov (United States)

2010-10-01

... MARITIME SERVICES Operating Requirements and Procedures Shipboard General Purpose Watches § 80.146 [Reserved] ... 47 Telecommunication 5 2010-10-01 2010-10-01 false [Reserved] 80.146 Section 80.146...

Effect of Yushen zhuyun decoction on rats with diminished ovarian ...

African Journals Online (AJOL)

biogenesis in cumulus cells. Hum Reprod 2015; 30: 1653-1664. 7. Feng JH, Kong LW, Li LL. Research progress of pathogeny and treatment of traditional Chinese and. Western medicine of decreasing ovarian reservation. Chin Med Hera 2014; 11: 161-164. 8. Roustan A, Perrin J, Debals-Gonthier M, Paulmyer-. Lacroix O ...

47 CFR 25.219 - [Reserved

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false [Reserved] 25.219 Section 25.219 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.219 [Reserved] ...

47 CFR 80.145 - [Reserved

Science.gov (United States)

2010-10-01

... MARITIME SERVICES Operating Requirements and Procedures Special Procedures-Ship Stations § 80.145 [Reserved] Shipboard General Purpose Watches ... 47 Telecommunication 5 2010-10-01 2010-10-01 false [Reserved] 80.145 Section 80.145...

5 CFR 330.610 - [Reserved

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false [Reserved] 330.610 Section 330.610 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS RECRUITMENT, SELECTION, AND... Employees § 330.610 [Reserved] ...

5 CFR 330.603 - [Reserved

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false [Reserved] 330.603 Section 330.603 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS RECRUITMENT, SELECTION, AND... Employees § 330.603 [Reserved] ...

40 CFR 405.73 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 28 2010-07-01 2010-07-01 true [Reserved] 405.73 Section 405.73 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS DAIRY... § 405.73 [Reserved] ...

Shell trips over its reserves

International Nuclear Information System (INIS)

Jemain, A.

2004-01-01

Some mistakes in the evaluation of the proven reserves of Royal Dutch Shell group, the second world petroleum leader, will oblige the other oil and gas companies to be more transparent and vigilant in the future. The proven reserves ('P90' in petroleum professionals' language) are the most important indicators of the mining patrimony of companies. These strategic data are reported each year in the annual reports of the companies and are examined by the security exchange commission. The evaluation of reserves is perfectly codified by the US energy policy and conservation act and its accountable translation using the FAS 69 standard allows to establish long-term cash-flow forecasts. The revision announced by Shell on January 9 leads to a 20% reduction of its proven reserves. Short paper. (J.S.)

Hydrocarbon Reserves: Abundance or Scarcity

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-01

IFP and the OAPEC jointly organize a regular international seminar dealing with world oil-related problems appearing in the news. For the first time, this seminar has been opened to oil and gas company specialists, service companies, research centers and independents. This year's theme concerns oil and gas reserves: are they abundant or are we headed towards the shortages announced by some experts? This theme is especially topical in that: oil and gas currently meet two thirds of world energy needs and almost completely dominate the transport sector; the reserves declared by the OAPEC countries account for nearly half of world reserves; the price of a barrel of oil went through the roof in 2004; world energy demand is growing fast and alternative sources of energy are far from ready to take over from oil and gas in the next few decades. Since the reserves correspond to the volume it is technically and economically viable to produce, the seminar has, of course, dealt with the technical and economic questions that arise in connection with exploration and production, but it has also considered changes in the geopolitical context. Presentations by the leading companies of the OAPEC countries and by the IFP group were completed by presentation from the International Energy Agency (IEA), the United States Geological Survey (USGS), the IHS Energy Group, Total and Gaz de France. This document gathers the transparencies of the following presentations: Hydrocarbon reserves in OAPEC members countries: current and future (M. Al-Lababidi); Non OAPEC liquid reserves and production forecasts (Y. Mathieu); World oil and gas resources and production outlook (K. Chew); Global investments in the upstream (F. Birol); Total's policy in the oil and gas sector (C. de Margerie); Gaz de France's policy in the oil and gas sector (J. Abiteboul); NOC/IOC's opportunities in OPEC countries (I. Sandrea); Relationships between companies, countries and investors: How they may

47 CFR 25.402 - [Reserved

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false [Reserved] 25.402 Section 25.402 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Competitive Bidding Procedures for DARS § 25.402 [Reserved] ...

40 CFR 408.73 - [Reserved

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2010-07-01

... 40 Protection of Environment 28 2010-07-01 2010-07-01 true [Reserved] 408.73 Section 408.73 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS... Processing Subcategory § 408.73 [Reserved] ...

40 CFR 407.73 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 28 2010-07-01 2010-07-01 true [Reserved] 407.73 Section 407.73 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS... Vegetables Subcategory § 407.73 [Reserved] ...

46 CFR 308.301 - [Reserved

Science.gov (United States)

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false [Reserved] 308.301 Section 308.301 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE Second Seamen's War Risk Insurance § 308.301 [Reserved] ...

46 CFR 308.305 - [Reserved

Science.gov (United States)

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false [Reserved] 308.305 Section 308.305 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE Second Seamen's War Risk Insurance § 308.305 [Reserved] ...

48 CFR 4.501 - [Reserved

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false [Reserved] 4.501 Section 4.501 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION GENERAL ADMINISTRATIVE MATTERS Electronic Commerce in Contracting 4.501 [Reserved] ...

49 CFR 17.4 - [Reserved

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2010-10-01

... 49 Transportation 1 2010-10-01 2010-10-01 false [Reserved] 17.4 Section 17.4 Transportation Office of the Secretary of Transportation INTERGOVERNMENTAL REVIEW OF DEPARTMENT OF TRANSPORTATION PROGRAMS AND ACTIVITIES § 17.4 [Reserved] ...

RNA-seq reveals a diminished acclimation response to the combined effects of ocean acidification and elevated seawater temperature in Pagothenia borchgrevinki.

Science.gov (United States)

Huth, Troy J; Place, Sean P

2016-08-01

The IPCC has reasserted the strong influence of anthropogenic CO2 contributions on global climate change and highlighted the polar-regions as highly vulnerable. With these predictions the cold adapted fauna endemic to the Southern Ocean, which is dominated by fishes of the sub-order Notothenioidei, will face considerable challenges in the near future. Recent physiological studies have demonstrated that the synergistic stressors of elevated temperature and ocean acidification have a considerable, although variable, impact on notothenioid fishes. The present study explored the transcriptomic response of Pagothenia borchgrevinki to increased temperatures and pCO2 after 7, 28 and 56days of acclimation. We compared this response to short term studies assessing heat stress alone and foretell the potential impacts of these stressors on P. borchgrevinki's ability to survive a changing Southern Ocean. P. borchgrevinki did demonstrate a coordinated stress response to the dual-stressor condition, and even indicated that some level of inducible heat shock response may be conserved in this notothenioid species. However, the stress response of P. borchgrevinki was considerably less robust than that observed previously in the closely related notothenioid, Trematomus bernacchii, and varied considerably when compared across different acclimation time-points. Furthermore, the molecular response of these fish under multiple stressors displayed distinct differences compared to their response to short term heat stress alone. When exposed to increased sea surface temperatures, combined with ocean acidification, P. borchgrevinki demonstrated a coordinated stress response that has already peaked by 7days of acclimation and quickly diminished over time. However, this response is less dramatic than other closely related notothenioids under identical conditions, supporting previous research suggesting that this notothenioid species is less sensitive to environmental variation. Copyright �

39 CFR 111.5 - [Reserved

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2010-07-01

... 39 Postal Service 1 2010-07-01 2010-07-01 false [Reserved] 111.5 Section 111.5 Postal Service UNITED STATES POSTAL SERVICE POST OFFICE SERVICES [DOMESTIC MAIL] GENERAL INFORMATION ON POSTAL SERVICE § 111.5 [Reserved] ...

7 CFR 801.10 - [Reserved

Science.gov (United States)

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false [Reserved] 801.10 Section 801.10 Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION, PACKERS AND STOCKYARD... FOR GRAIN INSPECTION EQUIPMENT § 801.10 [Reserved] ...

40 CFR 26.1124 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 1 2010-07-01 2010-07-01 false [Reserved] 26.1124 Section 26.1124 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GENERAL PROTECTION OF HUMAN SUBJECTS Basic Ethical...-nursing Adults § 26.1124 [Reserved] ...

40 CFR 73.51 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false [Reserved] 73.51 Section 73.51 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) SULFUR DIOXIDE ALLOWANCE SYSTEM Allowance Transfers § 73.51 [Reserved] ...

40 CFR 73.11 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false [Reserved] 73.11 Section 73.11 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) SULFUR DIOXIDE ALLOWANCE SYSTEM Allowance Allocations § 73.11 [Reserved] ...

Securities issues in reserves reporting

International Nuclear Information System (INIS)

Legg, M.B.

1997-01-01

Securities issues in oil and gas reserves reporting were discussed. Alberta requires specific information regarding important oil and gas properties, plants, facilities and installations. When preparing the reserves report, the following elements are important to consider: (1) the author of the report must be a registered professional engineer or registered professional geologist, (2) the report itself must be an engineering document, (3) the content of the report must be extensive, (4) it should be prepared in accordance with petroleum engineering and evaluation practices, and must include a summary of estimated net reserves

Food image-induced brain activation is not diminished by insulin infusion.

Science.gov (United States)

Belfort-DeAguiar, R; Seo, D; Naik, S; Hwang, J; Lacadie, C; Schmidt, C; Constable, R T; Sinha, R; Sherwin, R

2016-11-01

The obesity epidemic appears to be driven in large part by our modern environment inundated by food cues, which may influence our desire to eat. Although insulin decreases food intake in both animals and humans, the effect of insulin on motivation for food in the presence of food cues is not known. Therefore, the aim of this study was to evaluate the effect of an intravenous insulin infusion on the brain response to visual food cues, hunger and food craving in non-obese human subjects. Thirty-four right-handed healthy non-obese subjects (19F/15M, age: 29±8 years.; BMI: 23.1±2.1 kg m -2 ) were divided in two groups matched by age and BMI; the insulin group (18 subjects) underwent a hyperinsulinemic-euglycemic-clamp, and the control group (16 subjects) received an intravenous saline infusion, while viewing high and low-calorie food and non-food pictures during a functional MRI scan. Motivation for food was determined via analog scales for hunger, wanting and liking ratings. Food images induced brain responses in the hypothalamus, striatum, amygdala, insula, ventromedial prefrontal cortex (PFC), dorsolateral PFC and occipital lobe (whole brain correction, Pinsulin and saline infusion groups. Hunger ratings increased throughout the MRI scan and correlated with preference for high-calorie food pictures (r=0.70; Pbrain activity nor food cravings were affected by hyperinsulinemia or hormonal status (leptin and ghrelin levels) (P=NS). Our data demonstrate that visual food cues induce a strong response in motivation/reward and cognitive-executive control brain regions in non-obese subjects, but that these responses are not diminished by hyperinsulinemia per se. These findings suggest that our modern food cue saturated environment may be sufficient to overpower homeostatic hormonal signals, and thus contribute to the current obesity epidemic.

19 CFR 210.22 - [Reserved

Science.gov (United States)

2010-04-01

... 19 Customs Duties 3 2010-04-01 2010-04-01 false [Reserved] 210.22 Section 210.22 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION INVESTIGATIONS OF UNFAIR PRACTICES IN IMPORT TRADE ADJUDICATION AND ENFORCEMENT Motions § 210.22 [Reserved] ...

40 CFR 73.32 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false [Reserved] 73.32 Section 73.32 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) SULFUR DIOXIDE ALLOWANCE SYSTEM Allowance Tracking System § 73.32 [Reserved] ...

Poverty and corruption compromise tropical forest reserves.

Science.gov (United States)

Wright, S Joseph; Sanchez-Azofeifa, G Arturo; Portillo-Quintero, Carlos; Davies, Diane

2007-07-01

We used the global fire detection record provided by the satellite-based Moderate Resolution Imaging Spectroradiometer (MODIS) to determine the number of fires detected inside 823 tropical and subtropical moist forest reserves and for contiguous buffer areas 5, 10, and 15 km wide. The ratio of fire detection densities (detections per square kilometer) inside reserves to their contiguous buffer areas provided an index of reserve effectiveness. Fire detection density was significantly lower inside reserves than in paired, contiguous buffer areas but varied by five orders of magnitude among reserves. The buffer: reserve detection ratio varied by up to four orders of magnitude among reserves within a single country, and median values varied by three orders of magnitude among countries. Reserves tended to be least effective at reducing fire frequency in many poorer countries and in countries beset by corruption. Countries with the most successful reserves include Costa Rica, Jamaica, Malaysia, and Taiwan and the Indonesian island of Java. Countries with the most problematic reserves include Cambodia, Guatemala, Paraguay, and Sierra Leone and the Indonesian portion of Borneo. We provide fire detection density for 3964 tropical and subtropical reserves and their buffer areas in the hope that these data will expedite further analyses that might lead to improved management of tropical reserves.

Latitudinal Patterns in European Seagrass Carbon Reserves: Influence of Seasonal Fluctuations versus Short-Term Stress and Disturbance Events

Directory of Open Access Journals (Sweden)

Laura M. Soissons

2018-02-01

Full Text Available Seagrass meadows form highly productive and valuable ecosystems in the marine environment. Throughout the year, seagrass meadows are exposed to abiotic and biotic variations linked to (i seasonal fluctuations, (ii short-term stress events such as, e.g., local nutrient enrichment, and (iii small-scale disturbances such as, e.g., biomass removal by grazing. We hypothesized that short-term stress events and small-scale disturbances may affect seagrass chance for survival in temperate latitudes. To test this hypothesis we focused on seagrass carbon reserves in the form of starch stored seasonally in rhizomes, as these have been defined as a good indicator for winter survival. Twelve Zostera noltei meadows were monitored along a latitudinal gradient in Western Europe to firstly assess the seasonal change of their rhizomal starch content. Secondly, we tested the effects of nutrient enrichment and/or biomass removal on the corresponding starch content by using a short-term manipulative field experiment at a single latitude in the Netherlands. At the end of the growing season, we observed a weak but significant linear increase of starch content along the latitudinal gradient from south to north. This agrees with the contention that such reserves are essential for regrowth after winter, which is more severe in the north. In addition, we also observed a weak but significant positive relationship between starch content at the beginning of the growing season and past winter temperatures. This implies a lower regrowth potential after severe winters, due to diminished starch content at the beginning of the growing season. Short-term stress and disturbances may intensify these patterns, because our manipulative experiments show that when nutrient enrichment and biomass loss co-occurred at the end of the growing season, Z. noltei starch content declined. In temperate zones, the capacity of seagrasses to accumulate carbon reserves is expected to determine carbon

Latitudinal Patterns in European Seagrass Carbon Reserves: Influence of Seasonal Fluctuations versus Short-Term Stress and Disturbance Events

Science.gov (United States)

Soissons, Laura M.; Haanstra, Eeke P.; van Katwijk, Marieke M.; Asmus, Ragnhild; Auby, Isabelle; Barillé, Laurent; Brun, Fernando G.; Cardoso, Patricia G.; Desroy, Nicolas; Fournier, Jerome; Ganthy, Florian; Garmendia, Joxe-Mikel; Godet, Laurent; Grilo, Tiago F.; Kadel, Petra; Ondiviela, Barbara; Peralta, Gloria; Puente, Araceli; Recio, Maria; Rigouin, Loic; Valle, Mireia; Herman, Peter M. J.; Bouma, Tjeerd J.

2018-01-01

Seagrass meadows form highly productive and valuable ecosystems in the marine environment. Throughout the year, seagrass meadows are exposed to abiotic and biotic variations linked to (i) seasonal fluctuations, (ii) short-term stress events such as, e.g., local nutrient enrichment, and (iii) small-scale disturbances such as, e.g., biomass removal by grazing. We hypothesized that short-term stress events and small-scale disturbances may affect seagrass chance for survival in temperate latitudes. To test this hypothesis we focused on seagrass carbon reserves in the form of starch stored seasonally in rhizomes, as these have been defined as a good indicator for winter survival. Twelve Zostera noltei meadows were monitored along a latitudinal gradient in Western Europe to firstly assess the seasonal change of their rhizomal starch content. Secondly, we tested the effects of nutrient enrichment and/or biomass removal on the corresponding starch content by using a short-term manipulative field experiment at a single latitude in the Netherlands. At the end of the growing season, we observed a weak but significant linear increase of starch content along the latitudinal gradient from south to north. This agrees with the contention that such reserves are essential for regrowth after winter, which is more severe in the north. In addition, we also observed a weak but significant positive relationship between starch content at the beginning of the growing season and past winter temperatures. This implies a lower regrowth potential after severe winters, due to diminished starch content at the beginning of the growing season. Short-term stress and disturbances may intensify these patterns, because our manipulative experiments show that when nutrient enrichment and biomass loss co-occurred at the end of the growing season, Z. noltei starch content declined. In temperate zones, the capacity of seagrasses to accumulate carbon reserves is expected to determine carbon-based regrowth

Skyline Reservation System

Data.gov (United States)

US Agency for International Development — Flight reservation application used for in-country flights by USAID and DoS staff in Afghanistan. The application is managed and maintained by the vendor and USAID...

7 CFR 1900.57 - [Reserved

Science.gov (United States)

2010-01-01

... 7 Agriculture 12 2010-01-01 2010-01-01 false [Reserved] 1900.57 Section 1900.57 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE... GENERAL Adverse Decisions and Administrative Appeals § 1900.57 [Reserved] ...

22 CFR 99.3 - [Reserved

Science.gov (United States)

2010-04-01

... 22 Foreign Relations 1 2010-04-01 2010-04-01 false [Reserved] 99.3 Section 99.3 Foreign Relations DEPARTMENT OF STATE LEGAL AND RELATED SERVICES REPORTING ON CONVENTION AND NON-CONVENTION ADOPTIONS OF EMIGRATING CHILDREN § 99.3 [Reserved] ...

29 CFR 579.4 - [Reserved

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false [Reserved] 579.4 Section 579.4 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS CHILD LABOR VIOLATIONS-CIVIL MONEY PENALTIES § 579.4 [Reserved] ...

18 CFR 284.125 - [Reserved

Science.gov (United States)

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false [Reserved] 284.125 Section 284.125 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT... Certain Transportation by Intrastate Pipelines § 284.125 [Reserved] ...

Multiple educational programs improves glycemic control, quality of life with diminishing the impact of diabetes in poorly controlled type 1 diabetics.

Science.gov (United States)

Vyas, Chintan; Dalal, Lopa; Talaviya, Praful; Saboo, Banshi

2017-12-01

The aim of present study was to assess the outcomes of multiple educational programs on glycemic control, quality of life and impact of diabetes in poorly controlled Type 1 Diabetic patients. A 12 months diabetes education programs were conducted every week for first one month then followed by every 3 months with follow up on improvement of HbA1c and QOL in T1D patients (n=54). Clinical characteristics were recorded at baseline visit. The QOL was evaluated by 15 set DQOL questionnaires in 40 consecutive patients at baseline, 3, 6 and 12 months after education programs. The HbA1c level (%) was evaluated at same time point. Decrease in DQOL score was reported as improvement in QOL. The rate of patients response to educational programs was noted 74.07% (n=40) at end of the study (12 months). The prevalence of T1D was reported higher in men than in women. The overall DQOL score and HbA1c% level was significantly (Peducational programs. Patients exhibited greater satisfaction and diminished impact of diabetes after educational programs was observed after 3 months and it was continue up to end of study. The frequencies of self-monitoring of blood glucose were increased. Numbers of hypoglycemic and DKA events were decreased after educational programs when compared to baseline. Results of study revealed that the appropriate education and counseling diminish impact of diabetes, improve QOL and help to achieve desired glycemic (HbA1c) level in poorly control T1D patients. Copyright © 2017. Published by Elsevier Ltd.

40 CFR 406.43 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 28 2010-07-01 2010-07-01 true [Reserved] 406.43 Section 406.43 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Bulgur Wheat Flour Milling Subcategory § 406.43 [Reserved] ...

40 CFR 406.23 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 28 2010-07-01 2010-07-01 true [Reserved] 406.23 Section 406.23 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Corn Dry Milling Subcategory § 406.23 [Reserved] ...

40 CFR 406.13 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 28 2010-07-01 2010-07-01 true [Reserved] 406.13 Section 406.13 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS GRAIN MILLS POINT SOURCE CATEGORY Corn Wet Milling Subcategory § 406.13 [Reserved] ...

12 CFR 996.1 - [Reserved

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 7 2010-01-01 2010-01-01 false [Reserved] 996.1 Section 996.1 Banks and Banking FEDERAL HOUSING FINANCE BOARD NON-BANK SYSTEM ENTITIES AUTHORITY FOR BANK ASSISTANCE OF THE RESOLUTION FUNDING CORPORATION § 996.1 [Reserved] ...

5 CFR 9901.513 - [Reserved

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false [Reserved] 9901.513 Section 9901.513 Administrative Personnel DEPARTMENT OF DEFENSE HUMAN RESOURCES MANAGEMENT AND LABOR RELATIONS SYSTEMS (DEPARTMENT... (NSPS) Staffing and Employment External Recruitment and Internal Placement § 9901.513 [Reserved] ...

7 CFR 1776.4 - [Reserved

Science.gov (United States)

2010-01-01

... 7 Agriculture 12 2010-01-01 2010-01-01 false [Reserved] 1776.4 Section 1776.4 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE (CONTINUED) HOUSEHOLD WATER WELL SYSTEM GRANT PROGRAM General § 1776.4 [Reserved] ...

24 CFR 880.602 - Replacement reserve.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Replacement reserve. 880.602... Replacement reserve. (a) A replacement reserve must be established and maintained in an interest-bearing account to aid in funding extraordinary maintenance and repair and replacement of capital items. (1) Part...

24 CFR 572.125 - Replacement reserves.

Science.gov (United States)

2010-04-01

...) Homeownership Program Requirements-Implementation Grants § 572.125 Replacement reserves. (a) Purpose. A single replacement reserve may be established for the homeownership program only if HUD determines it is necessary to... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Replacement reserves. 572.125...

Reserve Component Members: A Report from the 1992 Reserve Components Survey

National Research Council Canada - National Science Library

Perry, Shelley

1997-01-01

...: amount of compensation and benefits, impact of service on civilian jobs and family life, quality of unit leadership, downsizing of Reserves, and perceptions about skill development and its relationship to civilian jobs...

Handbook on loss reserving

CERN Document Server

Schmidt, Klaus; Schnaus, Anja

2016-01-01

This handbook presents the basic aspects of actuarial loss reserving. Besides the traditional methods, it also includes a description of more recent ones and a discussion of certain problems occurring in actuarial practice, like inflation, scarce data, large claims, slow loss development, the use of market statistics, the need for simulation techniques and the task of calculating best estimates and ranges of future losses. In property and casualty insurance the provisions for payment obligations from losses that have occurred but have not yet been settled usually constitute the largest item on the liabilities side of an insurer's balance sheet. For this reason, the determination and evaluation of these loss reserves is of considerable economic importance for every property and casualty insurer. Actuarial students, academics as well as practicing actuaries will benefit from this overview of the most important actuarial methods of loss reserving by developing an understanding of the underlying stochastic models...

Physiological Levels of Nitric Oxide Diminish Mitochondrial Superoxide. Potential Role of Mitochondrial Dinitrosyl Iron Complexes and Nitrosothiols

Directory of Open Access Journals (Sweden)

Sergey I. Dikalov

2017-11-01

Full Text Available Mitochondria are the major source of superoxide radicals and superoxide overproduction contributes to cardiovascular diseases and metabolic disorders. Endothelial dysfunction and diminished nitric oxide levels are early steps in the development of these pathological conditions. It is known that physiological production of nitric oxide reduces oxidative stress and inflammation, however, the precise mechanism of “antioxidant” effect of nitric oxide is not clear. In this work we tested the hypothesis that physiological levels of nitric oxide diminish mitochondrial superoxide production without inhibition of mitochondrial respiration. In order to test this hypothesis we analyzed effect of low physiological fluxes of nitric oxide (20 nM/min on superoxide and hydrogen peroxide production by ESR spin probes and Amplex Red in isolated rat brain mitochondria. Indeed, low levels of nitric oxide substantially attenuated both basal and antimycin A-stimulated production of reactive oxygen species in the presence of succinate or glutamate/malate as mitochondrial substrates. Furthermore, slow releasing NO donor DPTA-NONOate (100 μM did not change oxygen consumption in State 4 and State 3. However, the NO-donor strongly inhibited oxygen consumption in the presence of uncoupling agent CCCP, which is likely associated with inhibition of the over-reduced complex IV in uncoupled mitochondria. We have examined accumulation of dinitrosyl iron complexes and nitrosothiols in mitochondria treated with fast-releasing NO donor MAHMA NONOate (10 μM for 30 min until complete release of NO. Following treatment with NO donor, mitochondria were frozen for direct detection of dinitrosyl iron complexes using Electron Spin Resonance (ESR while accumulation of nitrosothiols was measured by ferrous-N-Methyl-D-glucamine dithiocarbamate complex, Fe(MGD2, in lysed mitochondria. Treatment of mitochondria with NO-donor gave rise to ESR signal of dinitrosyl iron complexes while ESR

20 CFR 410.394 - [Reserved

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false [Reserved] 410.394 Section 410.394 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, TITLE IV-BLACK LUNG BENEFITS (1969- ) Relationship and Dependency § 410.394 [Reserved] ...

14 CFR 99.12 - [Reserved

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false [Reserved] 99.12 Section 99.12 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SECURITY CONTROL OF AIR TRAFFIC General § 99.12 [Reserved] ...

12 CFR 614.4710 - [Reserved

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false [Reserved] 614.4710 Section 614.4710 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM LOAN POLICIES AND OPERATIONS Banks for Cooperatives and Agricultural Credit Banks Financing International Trade § 614.4710 [Reserved] ...

7 CFR 1962.5 - [Reserved

Science.gov (United States)

2010-01-01

... 7 Agriculture 14 2010-01-01 2009-01-01 true [Reserved] 1962.5 Section 1962.5 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE... REGULATIONS (CONTINUED) PERSONAL PROPERTY Servicing and Liquidation of Chattel Security § 1962.5 [Reserved] ...

Metabolomic profile of umbilical cord blood plasma from early and late intrauterine growth restricted (IUGR neonates with and without signs of brain vasodilation.

Directory of Open Access Journals (Sweden)

Magdalena Sanz-Cortés

Full Text Available OBJECTIVES: To characterize via NMR spectroscopy the full spectrum of metabolic changes in umbilical vein blood plasma of newborns diagnosed with different clinical forms of intrauterine growth restriction (IUGR. METHODS: 23 early IUGR cases and matched 23 adequate-for-gestational-age (AGA controls and 56 late IUGR cases with 56 matched AGAs were included in this study. Early IUGR was defined as a birth weight 35 weeks. This group was subdivided in 18 vasodilated (VD and 38 non-VD late IUGR fetuses. All AGA patients had a birth weight >10(th centile. (1H nuclear magnetic resonance (NMR metabolomics of the blood samples collected from the umbilical vein at delivery was obtained. Multivariate statistical analysis identified several metabolites that allowed the discrimination between the different IUGR subgroups, and their comparative levels were quantified from the NMR data. RESULTS: The NMR-based analysis showed increased unsaturated lipids and VLDL levels in both early and late IUGR samples, decreased glucose and increased acetone levels in early IUGR. Non-significant trends for decreased glucose and increased acetone levels were present in late IUGR, which followed a severity gradient when the VD and non-VD subgroups were considered. Regarding amino acids and derivatives, early IUGR showed significantly increased glutamine and creatine levels, whereas the amounts of phenylalanine and tyrosine were decreased in early and late-VD IUGR samples. Valine and leucine were decreased in late IUGR samples. Choline levels were decreased in all clinical subforms of IUGR. CONCLUSIONS: IUGR is not associated with a unique metabolic profile, but important changes are present in different clinical subsets used in research and clinical practice. These results may help in characterizing comprehensively specific alterations underlying different IUGR subsets.

Effects of β-Blockers With and Without Vasodilating Properties on Central Blood Pressure: Systematic Review and Meta-Analysis of Randomized Trials in Hypertension.

Science.gov (United States)

Pucci, Giacomo; Ranalli, Maria Giovanna; Battista, Francesca; Schillaci, Giuseppe

2016-02-01

β-Blockers are less effective than other antihypertensive drug classes in reducing central systolic blood pressure (cSBP) as compared with peripheral SBP (pSBP). Whether this effect is less pronounced with vasodilating β-blockers (VBB) when compared with nonvasodilating β-blockers (NVBB) remains unsettled. We conducted a systematic review and meta-analysis of randomized trials exploring the effects of β-blockers on both pSBP and cSBP in hypertension. We selected 20 studies, for a total of 32 treatment arms (n=21 for NVBB, n=11 for VBB) and 1263 participants (n=962 for NVBB, n=301 for VBB). pSBP decreased from 150 to 133 mm Hg for NVBB and from 145 to 134 mm Hg for VBB. cSBP decreased from 137 to 126 mm Hg for NVBB and from 132 to 123 mm Hg for VBB. SBP amplification (pSBP-cSBP) decreased significantly under VBB (-5.6 mm Hg; 95% confidence interval, -7.8, -3.4 mm Hg), but not under NVBB (-1.1 mm Hg; 95% confidence interval, -3.4, +1.2 mm Hg; P<0.01 versus NVBB). There was high heterogeneity both within and between β-blockers subclasses. In a meta-regression model, the weighted difference in treatment-induced changes in SBP amplification between NVBB and VBB lost its significance after adjustment for mean age and baseline pSBP and heart rate (-2.9±2.3 mm Hg; P=0.22) and was almost abolished after adjustment for treatment-induced heart rate changes (-0.1±0.5 mm Hg; P=0.78). In conclusion, NVBBs, but not VBBs, determine a lower reduction in cSBP than in pSBP. However, the difference in treatment-induced SBP amplification changes between NVBB and VBB is nearly abolished after accounting for differences in heart rate changes. © 2015 American Heart Association, Inc.

Extractive reserves in Brazilian Amazonia

Energy Technology Data Exchange (ETDEWEB)

Fearnside, P.M (National Institute for Research in the Amazon, Manaus-Amazonas (Brazil))

1989-06-01

In 1985 an opportunity arose for maintaining tracts of Amazonian forest under sustainable use. Brazil's National Council of Rubber Tappers and the Rural Worker's Union proposed the creation of a set of reserves of a new type, called extractive reserves. The first six are being established in one of the Brazilian states most threatened by deforestatation. The creation of extractive reserves grants legal protection to forest land traditionally used by rubber tappers, Brazil-nut gatherers, and other extractivists. The term extrativismo (extractivism) in Brazil refers to removing nontimber forest products, such as latex, resins, and nuts, without felling the trees. Approximately 30 products are collected for commercial sale. Many more types of forest materials are gathered, for example as food and medicines, for the extractivists' own use. The reserve proposal is attractive for several reasons related to social problems. It allows the rubber tappers to continue their livelihood rather than be expelled by deforestation. However, it is unlikely that sufficient land will be set aside as extractive reserves to employ all the tappers. Displaced rubber tappers already swell the ranks of urban slum dwellers in Brazil's Amazonian cities, and they have become refugees to continue their profession in the forests of neighboring countries, such as Bolivia.

Inhaled therapy for the management of perioperative pulmonary hypertension

Directory of Open Access Journals (Sweden)

C A Thunberg

2015-01-01

Full Text Available Patients with pulmonary hypertension (PH are at high risk for complications in the perioperative setting and often receive vasodilators to control elevated pulmonary artery pressure (PAP. Administration of vasodilators via inhalation is an effective strategy for reducing PAP while avoiding systemic side effects, chiefly hypotension. The prototypical inhaled pulmonary-specific vasodilator, nitric oxide (NO, has a proven track record but is expensive and cumbersome to implement. Alternatives to NO, including prostanoids (such as epoprostenol, iloprost, and treprostinil, NO-donating drugs (sodium nitroprusside, nitroglycerin, and nitrite, and phosphodiesterase inhibitors (milrinone, sildenafil may be given via inhalation for the purpose of treating elevated PAP. This review will focus on the perioperative therapy of PH using inhaled vasodilators.

Reservation wages and starting wages

NARCIS (Netherlands)

van Ophem, H.; Hartog, J.; Berkhout, P.

2011-01-01

We analyse a unique data set that combines reservation wage and actually paid wage for a large sample of Dutch recent higher education graduates. On average, accepted wages are almost 8% higher than reservation wages, but there is no fixed proportionality. We find that the difference between

15 CFR 2003.3 - [Reserved

Science.gov (United States)

2010-01-01

... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false [Reserved] 2003.3 Section 2003.3 Commerce and Foreign Trade Regulations Relating to Foreign Trade Agreements OFFICE OF THE UNITED STATES TRADE REPRESENTATIVE REGULATIONS OF TRADE POLICY STAFF COMMITTEE § 2003.3 [Reserved] ...

31 CFR 281.2 - [Reserved

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false [Reserved] 281.2 Section 281.2 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE FOREIGN EXCHANGE OPERATIONS § 281.2 [Reserved] ...

Reserve evaluation of minerals at NUCLEBRAS

International Nuclear Information System (INIS)

Marques, J.P.M.; Guerra, P.A.G.; Vinha, C.A.G. da

1980-10-01

The method used for the reserve evaluation of minerals, particularly of uranium, as used worldwide, and specially at NUCLEBRAS is described. This is done through a series of procedures envolving basic definitions, reserve evaluation methods (conventional, statistical and geoestatistical), data management, use of computer systems, classification and evaluation of reserves. (Author) [pt

24 CFR 891.745 - Replacement reserve.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Replacement reserve. 891.745... and Individuals-Section 162 Assistance § 891.745 Replacement reserve. The general requirements for the replacement reserve are provided in § 891.605. For projects funded under §§ 891.655 through 891.790, the...

42 CFR 417.934 - Reserve requirement.

Science.gov (United States)

2010-10-01

... 42 Public Health 3 2010-10-01 2010-10-01 false Reserve requirement. 417.934 Section 417.934 Public... PLANS Administration of Outstanding Loans and Loan Guarantees § 417.934 Reserve requirement. (a) Timing... section 1305 of the PHS Act was required to establish a restricted reserve account on the earlier of the...

Cognitive Reserve Scale and ageing

Directory of Open Access Journals (Sweden)

Irene León

2016-01-01

Full Text Available The construct of cognitive reserve attempts to explain why some individuals with brain impairment, and some people during normal ageing, can solve cognitive tasks better than expected. This study aimed to estimate cognitive reserve in a healthy sample of people aged 65 years and over, with special attention to its influence on cognitive performance. For this purpose, it used the Cognitive Reserve Scale (CRS and a neuropsychological battery that included tests of attention and memory. The results revealed that women obtained higher total CRS raw scores than men. Moreover, the CRS predicted the learning curve, short-term and long-term memory, but not attentional and working memory performance. Thus, the CRS offers a new proxy of cognitive reserve based on cognitively stimulating activities performed by healthy elderly people. Following an active lifestyle throughout life was associated with better intellectual performance and positive effects on relevant aspects of quality of life.

Estimating Foreign Exchange Reserve Adequacy

Directory of Open Access Journals (Sweden)

Abdul Hakim

2013-04-01

Full Text Available Accumulating foreign exchange reserves, despite their cost and their impacts on other macroeconomics variables, provides some benefits. This paper models such foreign exchange reserves. To measure the adequacy of foreign exchange reserves for import, it uses total reserves-to-import ratio (TRM. The chosen independent variables are gross domestic product growth, exchange rates, opportunity cost, and a dummy variable separating the pre and post 1997 Asian financial crisis. To estimate the risky TRM value, this paper uses conditional Value-at-Risk (VaR, with the help of Glosten-Jagannathan-Runkle (GJR model to estimate the conditional volatility. The results suggest that all independent variables significantly influence TRM. They also suggest that the short and long run volatilities are evident, with the additional evidence of asymmetric effects of negative and positive past shocks. The VaR, which are calculated assuming both normal and t distributions, provide similar results, namely violations in 2005 and 2008.

Work to diminish the danger of forest fires in the municipalities San Antonio del Sur and Imías, Guantánamo

OpenAIRE

Edelmys Perez Pereda; Lianet Ramírez Fernández; Jessika Massó Matos; Francisco Duran Manual

2017-01-01

The research was carried out in the forest patrimony in San Antonio and Imías municipality in the province of Guantánamo, with the aim to propose actions to diminish the occurrence and propagation of the forest fires in the municipalities objects of study. For this, the temporal distribution of fires and burned areas, in the period 2006-2015, through the year, the week and the day was taken into account and also the causes that povoque the fires. With these elements, the activities to be carr...

Demand as frequency controlled reserve

Energy Technology Data Exchange (ETDEWEB)

Xu, Z.; Togeby, M.; OEstergaard, J.

2008-09-15

Using demand as frequency controlled reserve (DFR) is an emerging technology which allow demand to participate actively in maintaining the system operation without reducing the energy service delivered to the customer and without need of user interaction. The basic premise is that traditional frequency controlled reserves from power plants and interconnections with neighbouring systems can be costly, slow and not fulfil the need for future power grids with a high share of wind power and fewer central power plants, and an intention to perform flexible operation such as is landing. Electricity demands, on the other hand, have advantages as frequency reserve including fast activation speed, smooth linear activation, low expected costs, and well-dispersed in the distribution grid. The main challenge of DFR is new methods for monitoring the available capacity. This project has investigated the technology of using electricity demands for providing frequency reserve to power systems. Within the project the potential and economy of DFR compatible loads in Denmark has been investigated, control logic has been designed, power system impact has been investigated, potential business models has been evaluated and an implementation strategy has been suggested. The tasks and goals of the project have been successfully accomplished based on which the conclusion and future recommendation are made. This project has developed the DFR technology that enables electricity demands to autonomously disconnect or reconnect to the grid in response to system frequency variations. The developed DFR technology is proved to be a promising technology from several perspectives. Technically, using DFR is feasible to provide reserves and enhance power system frequency control, while fulfilling technical requirements such as linear activation (or reconnection) according to frequency (or time). Environmentally, the DFR technology is pollution free in contrast to traditional reserves from generation

Effect of indomethacin and salt depletion on renal proton MR imaging; An experimental study in the rat

Energy Technology Data Exchange (ETDEWEB)

Heyman, S.N.; Mammen, M. (Harvard Medical School, Boston, MA (United States). Charles A Dana Research Inst. Beth Israel Hospital, Boston, MA (United States))

1991-11-01

Blockade of the synthesis of vasodilating prostaglandins with non-steroidal anti-inflammatory drugs (NSAID) renders the renal medulla susceptible to hypoxic injury with reduced renal function, especially in clinical conditions characterized by volume depletion. Alterations in renal hemodynamics and urine production may effect renal MR imaging under these circumstances. We injected salt-depleted and control rats undergoing proton MR imaging with indomethacin 10 mg/kg. Indomethacin abolished the cortico-medullary T2-gradient and markedly diminished the overall renal signal in salt-depleted rats only. These changes, which progressed over a period of 40 min after indomethacin was injected, probably result from renal oligemia and decreased urine production, with an associated decrease in T2-values. We suggest that a history of consumption of non-steroidal anti-inflammatory drugs should be obtained and taken into account in the evaluation of renal proton MR imaging, especially in the presence of salt and volume depletion. (orig.).

Effect of indomethacin and salt depletion on renal proton MR imaging

International Nuclear Information System (INIS)

Heyman, S.N.; Mammen, M.

1991-01-01

Blockade of the synthesis of vasodilating prostaglandins with non-steroidal anti-inflammatory drugs (NSAID) renders the renal medulla susceptible to hypoxic injury with reduced renal function, especially in clinical conditions characterized by volume depletion. Alterations in renal hemodynamics and urine production may effect renal MR imaging under these circumstances. We injected salt-depleted and control rats undergoing proton MR imaging with indomethacin 10 mg/kg. Indomethacin abolished the cortico-medullary T2-gradient and markedly diminished the overall renal signal in salt-depleted rats only. These changes, which progressed over a period of 40 min after indomethacin was injected, probably result from renal oligemia and decreased urine production, with an associated decrease in T2-values. We suggest that a history of consumption of non-steroidal anti-inflammatory drugs should be obtained and taken into account in the evaluation of renal proton MR imaging, especially in the presence of salt and volume depletion. (orig.)

Effect of pinacidil on norepinephrine- and potassium-induced contractions and membrane potential in rat and human resistance vessels and in rat aorta

International Nuclear Information System (INIS)

Videbaek, L.M.; Aalkjaer, C.; Mulvany, M.J.

1988-01-01

The effect of pinacidil on contractile responses to norepinephrine, potassium, and membrane potential was examined in rat and human resistance vessels. In some experiments rat aorta was also used. Pinacidil (0.1-30 microM) caused a concentration-dependent relaxation of norepinephrine-induced contractions in all vessels studied. In the same concentration range, pinacidil had only little effect on potassium (125 mM) activated rat mesenteric and femoral resistance vessels. In denervated rat mesenteric resistance vessels, a depolarization with potassium (125 mM) before superimposing a norepinephrine tone markedly diminished the effect of pinacidil. In resting rat mesenteric resistance vessels, pinacidil (1-10 microM) caused a hyperpolarization of 10-15 mV. In rat aorta, pinacidil (10 microM) caused a significant (p less than 0.001) increase in 86 Rb+ efflux rate constant whereas 1 microM had no effect. The results of these experiments indicate that the vasodilating effect may be caused by a hyperpolarization of the vascular smooth muscle cell membrane

Reservation system with graphical user interface

KAUST Repository

Mohamed, Mahmoud A. Abdelhamid

2012-01-05

Techniques for providing a reservation system are provided. The techniques include displaying a scalable visualization object, wherein the scalable visualization object comprises an expanded view element of the reservation system depicting information in connection with a selected interval of time and a compressed view element of the reservation system depicting information in connection with one or more additional intervals of time, maintaining a visual context between the expanded view and the compressed view within the visualization object, and enabling a user to switch between the expanded view and the compressed view to facilitate use of the reservation system.

29 CFR 4.106 - [Reserved

Science.gov (United States)

2010-07-01

... 29 Labor 1 2010-07-01 2010-07-01 true [Reserved] 4.106 Section 4.106 Labor Office of the Secretary of Labor LABOR STANDARDS FOR FEDERAL SERVICE CONTRACTS Application of the McNamara-O'Hara Service Contract Act Introductory § 4.106 [Reserved] Agencies Whose Contracts May Be Covered ...

Brain reserve and cognitive reserve protect against cognitive decline over 4.5 years in MS.

Science.gov (United States)

Sumowski, James F; Rocca, Maria A; Leavitt, Victoria M; Dackovic, Jelena; Mesaros, Sarlota; Drulovic, Jelena; DeLuca, John; Filippi, Massimo

2014-05-20

Based on the theories of brain reserve and cognitive reserve, we investigated whether larger maximal lifetime brain growth (MLBG) and/or greater lifetime intellectual enrichment protect against cognitive decline over time. Forty patients with multiple sclerosis (MS) underwent baseline and 4.5-year follow-up evaluations of cognitive efficiency (Symbol Digit Modalities Test, Paced Auditory Serial Addition Task) and memory (Selective Reminding Test, Spatial Recall Test). Baseline and follow-up MRIs quantified disease progression: percentage brain volume change (cerebral atrophy), percentage change in T2 lesion volume. MLBG (brain reserve) was estimated with intracranial volume; intellectual enrichment (cognitive reserve) was estimated with vocabulary. We performed repeated-measures analyses of covariance to investigate whether larger MLBG and/or greater intellectual enrichment moderate/attenuate cognitive decline over time, controlling for disease progression. Patients with MS declined in cognitive efficiency and memory (p improve prediction of future cognitive decline in patients with MS. © 2014 American Academy of Neurology.

12 CFR 204.7 - Supplemental reserve requirement.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 2 2010-01-01 2010-01-01 false Supplemental reserve requirement. 204.7 Section... RESERVE REQUIREMENTS OF DEPOSITORY INSTITUTIONS (REGULATION D) § 204.7 Supplemental reserve requirement... reserve requirement on every depository institution of not more than 4 percent of its total transaction...

7 CFR 930.57 - Secondary inventory reserve.

Science.gov (United States)

2010-01-01

... shall retain control over the release of any cherries from the secondary inventory reserve. No cherries... 7 Agriculture 8 2010-01-01 2010-01-01 false Secondary inventory reserve. 930.57 Section 930.57... Handling Regulations § 930.57 Secondary inventory reserve. (a) In the event the inventory reserve...

7 CFR 981.51 - Requirements for reserve.

Science.gov (United States)

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Requirements for reserve. 981.51 Section 981.51... Regulating Handling Volume Regulation § 981.51 Requirements for reserve. Each handler may satisfy his reserve... include grade requirements for reserve almonds delivered to human consumption outlets. [41 FR 26853, June...

12 CFR 204.9 - Emergency reserve requirement.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 2 2010-01-01 2010-01-01 false Emergency reserve requirement. 204.9 Section... RESERVE REQUIREMENTS OF DEPOSITORY INSTITUTIONS (REGULATION D) § 204.9 Emergency reserve requirement. (a..., additional reserve requirements on depository institutions at any ratio on any liability upon a finding by at...

Arsenic transformation predisposes human skin keratinocytes to UV-induced DNA damage yet enhances their survival apparently by diminishing oxidant response

International Nuclear Information System (INIS)

Sun Yang; Kojima, Chikara; Chignell, Colin; Mason, Ronald; Waalkes, Michael P.

2011-01-01

Inorganic arsenic and UV, both human skin carcinogens, may act together as skin co-carcinogens. We find human skin keratinocytes (HaCaT cells) are malignantly transformed by low-level arsenite (100 nM, 30 weeks; termed As-TM cells) and with transformation concurrently undergo full adaptation to arsenic toxicity involving reduced apoptosis and oxidative stress response to high arsenite concentrations. Oxidative DNA damage (ODD) is a possible mechanism in arsenic carcinogenesis and a hallmark of UV-induced skin cancer. In the current work, inorganic arsenite exposure (100 nM) did not induce ODD during the 30 weeks required for malignant transformation. Although acute UV-treatment (UVA, 25 J/cm 2 ) increased ODD in passage-matched control cells, once transformed by arsenic to As-TM cells, acute UV actually further increased ODD (> 50%). Despite enhanced ODD, As-TM cells were resistant to UV-induced apoptosis. The response of apoptotic factors and oxidative stress genes was strongly mitigated in As-TM cells after UV exposure including increased Bcl2/Bax ratio and reduced Caspase-3, Nrf2, and Keap1 expression. Several Nrf2-related genes (HO-1, GCLs, SOD) showed diminished responses in As-TM cells after UV exposure consistent with reduced oxidant stress response. UV-exposed As-TM cells showed increased expression of cyclin D1 (proliferation gene) and decreased p16 (tumor suppressor). UV exposure enhanced the malignant phenotype of As-TM cells. Thus, the co-carcinogenicity between UV and arsenic in skin cancer might involve adaptation to chronic arsenic exposure generally mitigating the oxidative stress response, allowing apoptotic by-pass after UV and enhanced cell survival even in the face of increased UV-induced oxidative stress and increased ODD. - Highlights: → Arsenic transformation adapted to UV-induced apoptosis. → Arsenic transformation diminished oxidant response. → Arsenic transformation enhanced UV-induced DNA damage.

26 CFR 1.801-5 - Total reserves.

Science.gov (United States)

2010-04-01

... TAXES Life Insurance Companies § 1.801-5 Total reserves. (a) Total reserves defined. For purposes of... its highest aggregate reserve by taking State A's requirement of 10 against its life insurance business and adding it to State B's requirement of 7 against its annuity business. (b) Reserves required by...

Can Creativity Predict Cognitive Reserve?

Science.gov (United States)

Palmiero, Massimiliano; Di Giacomo, Dina; Passafiume, Domenico

2016-01-01

Cognitive reserve relies on the ability to effectively cope with aging and brain damage by using alternate processes to approach tasks when standard approaches are no longer available. In this study, the issue if creativity can predict cognitive reserve has been explored. Forty participants (mean age: 61 years) filled out: the Cognitive Reserve…

Instantaneous wave-free ratio as an alternative to fractional flow reserve in assessment of moderate coronary stenoses: A meta-analysis of diagnostic accuracy studies.

Science.gov (United States)

Maini, Rohit; Moscona, John; Katigbak, Paul; Fernandez, Camilo; Sidhu, Gursukhmandeep; Saleh, Qusai; Irimpen, Anand; Samson, Rohan; LeJemtel, Thierry

2017-12-27

Fractional flow reserve (FFR) remains underutilized due to practical concerns related to the need for hyperemic agents. These concerns have prompted the study of instantaneous wave-free ratio (iFR), a vasodilator-free index of coronary stenosis. Non-inferior cardiovascular outcomes have been demonstrated in two recent randomized clinic trials. We performed this meta-analysis to provide a necessary update of the diagnostic accuracy of iFR referenced to FFR based on the addition of eight more recent studies and 3727 more lesions. We searched the PubMed, EMBASE, Central, ProQuest, and Web of Science databases for full text articles published through May 31, 2017 to identify studies addressing the diagnostic accuracy of iFR referenced to FFR≤0.80. The following keywords were used: "instantaneous wave-free ratio" OR "iFR" AND "fractional flow reserve" OR "FFR." In total, 16 studies comprising 5756 lesions were identified. Pooled diagnostic accuracy estimates of iFR versus FFR≤0.80 were: sensitivity, 0.78 (95% CI, 0.76-0.79); specificity, 0.83 (0.81-0.84); positive likelihood ratio, 4.54 (3.85-5.35); negative likelihood ratio, 0.28 (0.24-0.32); diagnostic odds ratio, 17.38 (14.16-21.34); area under the summary receiver-operating characteristic curve, 0.87; and an overall diagnostic accuracy of 0.81 (0.78-0.84). In conclusion, iFR showed excellent agreement with FFR as a resting index of coronary stenosis severity without the undesired effects and cost of hyperemic agents. When considering along with its clinical outcome data and ease of application, the diagnostic accuracy of iFR supports its use as a suitable alternative to FFR for physiology-guided revascularization of moderate coronary stenoses. We performed a meta-analysis of the diagnostic accuracy of iFR referenced to FFR. iFR showed excellent agreement with FFR as a resting index of coronary stenosis severity without the undesired effects and cost of hyperemic agents. This supports its use as a suitable

Veterinary Science Students, Center Changing a Reservation

Science.gov (United States)

Blackwater, Jasmine

2011-01-01

Kayenta is a rural community located in northeastern Arizona on a Navajo reservation. On the reservation, many families rely on their livestock for income, and as a result, many reservation high school students show a great interest in agricultural education. Having livestock on the reservation is not just a source of income, but also part of a…

Kaempferol stimulates large conductance Ca2+-activated K+ (BKCa) channels in human umbilical vein endothelial cells via a cAMP/PKA-dependent pathway

Science.gov (United States)

Xu, Y C; Leung, G P H; Wong, P Y D; Vanhoutte, P M; Man, R Y K

2008-01-01

Background and purpose: Kaempferol has been shown to possess a vasodilator effect but its mechanism of action remains unclear. In this study, experiments were carried out to study the effect of kaempferol on K+ channels in endothelial cells. Experimental approach: K+ channel activities in human umbilical vein endothelial cells (HUVECs) were studied by conventional whole cell and cell-attached patch-clamp electrophysiology. Key results: Kaempferol stimulated an outward-rectifying current in HUVECs in a dose-dependent manner with an EC50 value of 2.5±0.02 μM. This kaempferol-induced current was abolished by large conductance Ca2+-activated K+ (BKCa) channel blockers, such as iberiotoxin (IbTX) and charybdotoxin (ChTX), whereas the small conductance Ca2+-activated K+ (SKCa) channel blocker, apamin, and the voltage-dependent K+ (KV) channel blocker, 4-aminopyridine, had no effect. Cell-attached patches demonstrated that kaempferol increased the open probability of BkCa channels in HUVECs. Clamping intracellular Ca2+ did not prevent kaempferol-induced increases in outward current. In addition, the kaempferol-induced current was diminished by the adenylyl cyclase inhibitor SQ22536, the cAMP antagonist Rp-8-Br-cAMP and the PKA inhibitor KT5720, but was not affected by the guanylyl cyclase inhibitor ODQ, the cGMP antagonist Rp-8-Br-cGMP and the PKG inhibitor KT5823. The activation of BKCa channels by kaempferol caused membrane hyperpolarization of HUVECs. Conclusion and implications: These results demonstrate that kaempferol activates the opening of BKCa channels in HUVECs via a cAMP/PKA-dependent pathway, resulting in membrane hyperpolarization. This mechanism may partly account for the vasodilator effects of kaempferol. PMID:18493242

Selling the SPR [Strategic Petroleum Reserve

International Nuclear Information System (INIS)

Gurney, J.

1997-01-01

The Strategic Petroleum Reserve (SPR) in the USA was created in 1975, in conjunction with the wider reserve programme of the International Energy Agency, following the 1973/74 Arab oil embargo. The only source of funding for the SPR has been annual appropriations bills from Congress. In 1994, however, Congress, seeking ways to balance the nation's budget and given the perception by many free market economists that the danger of serious oils supply disruption has passed, refused to allocate funds for SPR oil purchases. No crude oil stocks have been added to the reserve since then. In 1996, congress took the further step of requiring sales of oil from the reserve in order to pay for the programme's running costs and to meet the costs of maintaining the reserve's storage facilities. The reserve oil is stored in caverns under salt domes in the coastal regions of the Gulf of Mexico and some of these are beginning to fracture to the extent that they are having to be decommissioned. The SPR has been investigating ways of raising money in order to lessen its dependence on Congress. These include leasing pipelines and a marine terminal, and allowing the storage of foreign owned oil in underused caverns. (author)

Substantiating the Incurred but not Reported Reserve

Directory of Open Access Journals (Sweden)

Georgeta Vintilã

2009-12-01

Full Text Available In order to handle past and future liability taken by insurance contracts concluded, any insurance company must constitute and maintain technical reserves. Substantiating technical reserves is done through actuarial methods and its over-evaluation or under-evaluation influence solvency and financial performance of the insurance companies, in the sense of reducing solvency through over-evaluating reserves and, respectively, influencing profit (hence of outstanding tax through under-evaluating reserves. An important reserve for insurance companies is represented by the incurred but not reported reserve, as it allows the estimation of the liability the company may confront in the future, generated by events occurred in the past, which are not currently known in the present but will be reported in the future.

Ginger extract diminishes chronic fructose consumption-induced kidney injury through suppression of renal overexpression of proinflammatory cytokines in rats.

Science.gov (United States)

Yang, Ming; Liu, Changjin; Jiang, Jian; Zuo, Guowei; Lin, Xuemei; Yamahara, Johji; Wang, Jianwei; Li, Yuhao

2014-05-27

The metabolic syndrome is associated with an increased risk of development and progression of chronic kidney disease. Renal inflammation is well known to play an important role in the initiation and progression of tubulointerstitial injury of the kidneys. Ginger, one of the most commonly used spices and medicinal plants, has been demonstrated to improve diet-induced metabolic abnormalities. However, the efficacy of ginger on the metabolic syndrome-associated kidney injury remains unknown. This study aimed to investigate the impact of ginger on fructose consumption-induced adverse effects in the kidneys. The fructose control rats were treated with 10% fructose in drinking water over 5 weeks. The fructose consumption in ginger-treated rats was adjusted to match that of fructose control group. The ethanolic extract of ginger was co-administered (once daily by oral gavage). The indexes of lipid and glucose homeostasis were determined enzymatically, by ELISA and/or histologically. Gene expression was analyzed by Real-Time PCR. In addition to improve hyperinsulinemia and hypertriglyceridemia, supplement with ginger extract (50 mg/kg) attenuated liquid fructose-induced kidney injury as characterized by focal cast formation, slough and dilation of tubular epithelial cells in the cortex of the kidneys in rats. Furthermore, ginger also diminished excessive renal interstitial collagen deposit. By Real-Time PCR, renal gene expression profiles revealed that ginger suppressed fructose-stimulated monocyte chemoattractant protein-1 and its receptor chemokine (C-C motif) receptor-2. In accord, overexpression of two important macrophage accumulation markers CD68 and F4/80 was downregulated. Moreover, overexpressed tumor necrosis factor-alpha, interleukin-6, transforming growth factor-beta1 and plasminogen activator inhibitor (PAI)-1 were downregulated. Ginger treatment also restored the downregulated ratio of urokinase-type plasminogen activator to PAI-1. The present results

The energy reserves of our planet

International Nuclear Information System (INIS)

Bischoff, G.

1977-01-01

Starting from a prognosis for the development of the world energy consumption, the situation of special primary energy sources (reserves, potential) is briefly described. According to the amount and location of the reserves - 90% of the fossil energy reserves are in industrialized countries -, coal will play a leading role in meeting the energy demands of the future. Without breeder reactors, the role of nuclear energy will be limited in time. (UA) [de

Reserve requirement systems in OECD countries

OpenAIRE

Yueh-Yun C. O’Brien

2007-01-01

This paper compares the reserve requirements of OECD countries. Reserve requirements are the minimum percentages or amounts of liabilities that depository institutions are required to keep in cash or as deposits with their central banks. To facilitate monetary policy implementation, twenty-four of the thirty OECD countries impose reserve requirements to influence their banking systems’ demand for liquidity. These include twelve OECD countries that are also members of the European Economic and...

Sarpogrelate hydrochloride, a selective 5-hydroxytryptamine(2A) antagonist, augments autologous bone marrow mononuclear cell implantation-induced improvement in endothelium-dependent vasodilation in patients with critical limb ischemia.

Science.gov (United States)

Higashi, Yukihito; Miyazaki, Masanori; Goto, Chikara; Sanada, Hiroaki; Sueda, Taijiro; Chayama, Kazuaki

2010-01-01

The purpose of this study was to determine the effect of a combination of bone marrow mononuclear cell (BM-MNC) implantation and sarpogrelate, a selective 5-HT(2A) antagonist, on endothelial function in patients with critical limb ischemia (CLI). We evaluated the leg blood flow (LBF) responses to acetylcholine (ACh) and sodium nitroprusside before and after BM-MNC implantation in 16 patients with CLI. We divided patients with CLI into 2 groups: those cotreated with sarpogrelate orally for 12 weeks (sarpogrelate group, n = 8) and those who remained on conventional therapy (control group, n = 8). LBF was measured by strain gauge plethysmography. BM-MNC implantation improved ankle brachial pressure index, transcutaneous oxygen pressure, and pain-free walking time. There was no significant difference in these parameters between the 2 groups. Before BM-MNC implantation, LBF responses to ACh were similar in the sarpogrelate group and control group. Twelve weeks of BM-MNC implantation enhanced LBF responses to ACh in the sarpogrelate and control groups. After 12 weeks of BM-MNC implantation, LBF response to ACh was significantly greater in the sarpogrelate group than in the control group. BM-MNC implantation did not alter the LBF responses to sodium nitroprusside in either group. These findings suggest that BM-MNC implantation improved not only limb ischemic symptoms but also endothelium-dependent vasodilation in patients with CLI. A combination of BM-MNC implantation and sarpogrelate had a more beneficial effect on vascular function in these patients.

The Economics of NASA Mission Cost Reserves

Science.gov (United States)

Whitley, Sally; Shinn, Stephen

2012-01-01

Increases in NASA mission costs are well-noted but not well-understood, and there is little evidence that they are decreasing in frequency or amount over time. The need to control spending has led to analysis of the causes and magnitude of historical mission overruns, and many program control efforts are being implemented to attempt to prevent or mitigate the problem (NPR 7120). However, cost overruns have not abated, and while some direct causes of increased spending may be obvious (requirements creep, launch delays, directed changes, etc.), the underlying impetus to spend past the original budget may be more subtle. Gaining better insight into the causes of cost overruns will help NASA and its contracting organizations to avoid .them. This paper hypothesizes that one cause of NASA mission cost overruns is that the availability of reserves gives project team members an incentive to make decisions and behave in ways that increase costs. We theorize that the presence of reserves is a contributing factor to cost overruns because it causes organizations to use their funds less efficiently or to control spending less effectively. We draw a comparison to the insurance industry concept of moral hazard, the phenomenon that the presence of insurance causes insureds to have more frequent and higher insurance losses, and we attempt to apply actuarial techniques to quantifY the increase in the expected cost of a mission due to the availability of reserves. We create a theoretical model of reserve spending motivation by defining a variable ReserveSpending as a function of total reserves. This function has a positive slope; for every dollar of reserves available, there is a positive probability of spending it. Finally, the function should be concave down; the probability of spending each incremental dollar of reserves decreases progressively. We test the model against available NASA CADRe data by examining missions with reserve dollars initially available and testing whether

blood pressure reducing effect of bitter kola in wistar rats

African Journals Online (AJOL)

DEAN'S OFFICE

characteristics of the action potential and these alterations cause ... cyclic AMP pathway is another process by which some vasodilators ... because the fact that cyclic AMP itself, causes .... potentiating the vasodilator function of Nitroglycerine.

A comparison of organic and inorganic nitrates/nitrites.

Science.gov (United States)

Omar, Sami A; Artime, Esther; Webb, Andrew J

2012-05-15

Although both organic and inorganic nitrates/nitrites mediate their principal effects via nitric oxide, there are many important differences. Inorganic nitrate and nitrite have simple ionic structures and are produced endogenously and are present in the diet, whereas their organic counterparts are far more complex, and, with the exception of ethyl nitrite, are all medicinally synthesised products. These chemical differences underlie the differences in pharmacokinetic properties allowing for different modalities of administration, particularly of organic nitrates, due to the differences in their bioavailability and metabolic profiles. Whilst the enterosalivary circulation is a key pathway for orally ingested inorganic nitrate, preventing an abrupt effect or toxic levels of nitrite and prolonging the effects, this is not used by organic nitrates. The pharmacodynamic differences are even greater; while organic nitrates have potent acute effects causing vasodilation, inorganic nitrite's effects are more subtle and dependent on certain conditions. However, in chronic use, organic nitrates are considerably limited by the development of tolerance and endothelial dysfunction, whereas inorganic nitrate/nitrite may compensate for diminished endothelial function, and tolerance has not been reported. Also, while inorganic nitrate/nitrite has important cytoprotective effects against ischaemia-reperfusion injury, continuous use of organic nitrates may increase injury. While there are concerns that inorganic nitrate/nitrite may induce carcinogenesis, direct evidence of this in humans is lacking. While organic nitrates may continue to dominate the therapeutic arena, this may well change with the increasing recognition of their limitations, and ongoing discovery of beneficial effects and specific advantages of inorganic nitrate/nitrite. Copyright © 2012 Elsevier Inc. All rights reserved.

Reservation system with graphical user interface

KAUST Repository

Mohamed, Mahmoud A. Abdelhamid; Jamjoom, Hani T.; Podlaseck, Mark E.; Qu, Huiming; Shae, Zon-Yin; Sheopuri, Anshul

2012-01-01

Techniques for providing a reservation system are provided. The techniques include displaying a scalable visualization object, wherein the scalable visualization object comprises an expanded view element of the reservation system depicting

Availability of neurotransmitter glutamate is diminished when beta-hydroxybutyrate replaces glucose in cultured neurons.

Science.gov (United States)

Lund, Trine M; Risa, Oystein; Sonnewald, Ursula; Schousboe, Arne; Waagepetersen, Helle S

2009-07-01

Ketone bodies serve as alternative energy substrates for the brain in cases of low glucose availability such as during starvation or in patients treated with a ketogenic diet. The ketone bodies are metabolized via a distinct pathway confined to the mitochondria. We have compared metabolism of [2,4-(13)C]beta-hydroxybutyrate to that of [1,6-(13)C]glucose in cultured glutamatergic neurons and investigated the effect of neuronal activity focusing on the aspartate-glutamate homeostasis, an essential component of the excitatory activity in the brain. The amount of (13)C incorporation and cellular content was lower for glutamate and higher for aspartate in the presence of [2,4-(13)C]beta-hydroxybutyrate as opposed to [1,6-(13)C]glucose. Our results suggest that the change in aspartate-glutamate homeostasis is due to a decreased availability of NADH for cytosolic malate dehydrogenase and thus reduced malate-aspartate shuttle activity in neurons using beta-hydroxybutyrate. In the presence of glucose, the glutamate content decreased significantly upon activation of neurotransmitter release, whereas in the presence of only beta-hydroxybutyrate, no decrease in the glutamate content was observed. Thus, the fraction of the glutamate pool available for transmitter release was diminished when metabolizing beta-hydroxybutyrate, which is in line with the hypothesis of formation of transmitter glutamate via an obligatory involvement of the malate-aspartate shuttle.

Changes in Habitat Structure May Explain Decrease in Reintroduced Mohor Gazelle Population in the Guembeul Fauna Reserve, Senegal

Directory of Open Access Journals (Sweden)

Eulalia Moreno

2012-08-01

Full Text Available Reintroduction is a widespread method for saving populations of endangered species from extinction. In spite of recent reviews, it is difficult to reach general conclusions about its value as a conservation tool, as authors are reluctant to publish unsuccessful results. The Mohor gazelle is a North African gazelle, extinct in the wild. Eight individuals were reintroduced in Senegal in 1984. The population grew progressively, albeit slowly, during the first 20 years after release, but then declined dramatically, until the population in 2009 was estimated at no more than 13–15 individuals. This study attempts to determine the likelihood of gazelle-habitat relationships to explain why the size of the gazelle population has diminished. Our results show that the Mohor gazelle in Guembeul is found in open habitats with less developed canopy where the grass is shorter, suggesting the possibility that changes in habitat structure have taken place during the time the gazelles have been in the Reserve, reducing the amount of suitable habitat. Reintroduction design usually concentrates on short-term factors that may affect survival of the released animals and their descendants (short-term achievement, while the key factors for assessing its success may be those that affect the long-term evolution of the population.

Autonomic Blockade Reverses Endothelial Dysfunction in Obesity-Associated Hypertension.

Science.gov (United States)

Gamboa, Alfredo; Figueroa, Rocío; Paranjape, Sachin Y; Farley, Ginnie; Diedrich, Andre; Biaggioni, Italo

2016-10-01

Impaired nitric oxide (NO) vasodilation (endothelial dysfunction) is associated with obesity and thought to be a factor in the development of hypertension. We previously found that NO synthesis inhibition had similar pressor effects in obese hypertensives compared with healthy control during autonomic blockade, suggesting that impaired NO vasodilation is secondary to sympathetic activation. We tested this hypothesis by determining the effect of autonomic blockade (trimethaphan 4 mg/min IV) on NO-mediated vasodilation (increase in forearm blood flow to intrabrachial acetylcholine) compared with endothelial-independent vasodilation (intrabrachial sodium nitroprusside) in obese hypertensive subjects (30blood flow (from 3.9±0.7 to 5.2±1.2 mL/100 mL per minute, P=0.078). As expected, NO-mediated vasodilation was blunted on the intact day compared with NO-independent vasodilation; forearm blood flow increased from 3.6±0.6 to 10.1±1.1 with the highest dose of nitroprusside, but only from 3.7±0.4 to 7.2±0.8 mL/100 mL per minute with the highest dose of acetylcholine, Pblood flow responses to acetylcholine were restored by autonomic blockade and were no longer different to nitroprusside (from 6.2±1.1 to 11.4±1.6 mL/100 mL per minute and from 5.2±0.9 to 12.5±0.9, respectively, P=0.58). Our results support the concept that sympathetic activation contributes to the impairment in NO-mediated vasodilation seen in obesity-associated hypertension and provides further rationale to explore it as a therapeutic target. © 2016 American Heart Association, Inc.

78 FR 50038 - National Estuarine Research Reserve System

Science.gov (United States)

2013-08-16

....33(c), the revised plan meets the reserve's requirements for compliance. The Wells Reserve Management... Reserve System AGENCY: Estuarine Reserves Division, Office of Ocean and Coastal Resource Management.... ACTION: Notice of Public Comment Period for the Wells, Maine National Estuarine Research Reserve...

Peripheral and central vascular conductance influence on post-exercise hypotension

Directory of Open Access Journals (Sweden)

Endo Masako Y

2012-12-01

Full Text Available Abstract Background Post-exercise hypotension (PEH following prolonged dynamic exercise arises from increased total vascular conductance (TVC via skeletal muscle vasodilation. However, arterial vasodilation of skeletal musculatures does not entirely account for the rise in TVC. The aim of the present study was to determine the contribution of vascular conductance (VC of the legs, arms, kidneys and viscera to TVC during PEH. Methods Eight subjects performed a single period of cycling at 60% of heart rate (HR reserve for 60 minutes. Blood flow in the right renal, superior mesenteric, right brachial and right femoral arteries was measured by Doppler ultrasonography in a supine position before exercise and during recovery. HR and mean arterial pressure (MAP were measured continuously. MAP decreased significantly from approximately 25 minutes after exercise cessation compared with pre-exercise baseline. TVC significantly increased (approximately 23%; P Conclusion PEH was not induced by decreased cardiac output, but by increased TVC, two-thirds of the rise in which can be attributed to increased VC in active and inactive limbs.

76 FR 68064 - Reserve Requirements of Depository Institutions

Science.gov (United States)

2011-11-03

... Reserve Requirements of Depository Institutions AGENCY: Board of Governors of the Federal Reserve System. ACTION: Final rule. SUMMARY: The Board is amending Regulation D, Reserve Requirements of Depository Institutions, to reflect the annual indexing of the reserve requirement exemption amount and the low reserve...

12 CFR 204.4 - Computation of required reserves.

Science.gov (United States)

2010-01-01

... RESERVE REQUIREMENTS OF DEPOSITORY INSTITUTIONS (REGULATION D) § 204.4 Computation of required reserves. (a) In determining the reserve requirement under this part, the amount of cash items in process of... reserves are computed by applying the reserve requirement ratios below to net transaction accounts...

High Working Memory Load Increases Intracortical Inhibition in Primary Motor Cortex and Diminishes the Motor Affordance Effect.

Science.gov (United States)

Freeman, Scott M; Itthipuripat, Sirawaj; Aron, Adam R

2016-05-18

Motor affordances occur when the visual properties of an object elicit behaviorally relevant motor representations. Typically, motor affordances only produce subtle effects on response time or on motor activity indexed by neuroimaging/neuroelectrophysiology, but sometimes they can trigger action itself. This is apparent in "utilization behavior," where individuals with frontal cortex damage inappropriately grasp affording objects. This raises the possibility that, in healthy-functioning individuals, frontal cortex helps ensure that irrelevant affordance provocations remain below the threshold for actual movement. In Experiment 1, we tested this "frontal control" hypothesis by "loading" the frontal cortex with an effortful working memory (WM) task (which ostensibly consumes frontal resources) and examined whether this increased EEG measures of motor affordances to irrelevant affording objects. Under low WM load, there were typical motor affordance signatures: an event-related desynchronization in the mu frequency and an increased P300 amplitude for affording (vs nonaffording) objects over centroparietal electrodes. Contrary to our prediction, however, these affordance measures were diminished under high WM load. In Experiment 2, we tested competing mechanisms responsible for the diminished affordance in Experiment 1. We used paired-pulse transcranial magnetic stimulation over primary motor cortex to measure long-interval cortical inhibition. We found greater long-interval cortical inhibition for high versus low load both before and after the affording object, suggesting that a tonic inhibition state in primary motor cortex could prevent the affordance from provoking the motor system. Overall, our results suggest that a high WM load "sets" the motor system into a suppressed state that mitigates motor affordances. Is an irrelevant motor affordance more likely to be triggered when you are under low or high cognitive load? We examined this using physiological measures

Session 7: Reserve

International Nuclear Information System (INIS)

Bailey, R.; Crockford, G.

2001-01-01

The reserve session was devoted to some issues that came up through the workshop, which were grouped into three main areas: The Global Accelerator Network, Problems of stress and how to get organized to minimize them, What should an operations group be responsible for? This paper summarizes the discussions that took place. (author)

Reserve reporting from a banker's perspective

International Nuclear Information System (INIS)

Larson, B.O.

1996-01-01

A banker's perspective of oil and gas reserve reporting was presented. Topics chosen for discussion emphasized oil and gas lending, and the type of capital which is most relevant to the oil and gas industry. The concept of capital differentiation, potential worst case, and least specialization, were explained. An explanation of the reasons for the lender's different perspective on reserves was given. Methods that banks use to limit risk, and the role that reserve reports play in loan approvals were also reviewed

Spearman's "law of diminishing returns" and the role of test reliability investigated in a large sample of Danish military draftees

DEFF Research Database (Denmark)

Teasdale, Thomas William; Hartmann, P.

2005-01-01

The present article investigates Spearman's "Law of Diminishing Returns" (SLODR), which hypothesizes that the g saturation for cognitive tests is lower for high ability subjects than for low ability subjects. This hypothesis was tested in a large sample of Danish military draftees (N = 6757) who...... were representative of the young adult male population, aged 18-19, and tested with a group-administered intelligence test comprised of four subtests. The aim of the study was twofold. The first was to reproduce previous SLODR findings by the present authors. This was done by replicating...... in reliability could account for the difference in g saturation across ability groups. The results showed that the reliability was larger for the High ability group, thereby not explaining the present findings....

7 CFR 1709.202 Policy. - [Reserved

Science.gov (United States)

2010-01-01

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A General Business Model for Marine Reserves

Science.gov (United States)

Sala, Enric; Costello, Christopher; Dougherty, Dawn; Heal, Geoffrey; Kelleher, Kieran; Murray, Jason H.; Rosenberg, Andrew A.; Sumaila, Rashid

2013-01-01

Marine reserves are an effective tool for protecting biodiversity locally, with potential economic benefits including enhancement of local fisheries, increased tourism, and maintenance of ecosystem services. However, fishing communities often fear short-term income losses associated with closures, and thus may oppose marine reserves. Here we review empirical data and develop bioeconomic models to show that the value of marine reserves (enhanced adjacent fishing + tourism) may often exceed the pre-reserve value, and that economic benefits can offset the costs in as little as five years. These results suggest the need for a new business model for creating and managing reserves, which could pay for themselves and turn a profit for stakeholder groups. Our model could be expanded to include ecosystem services and other benefits, and it provides a general framework to estimate costs and benefits of reserves and to develop such business models. PMID:23573192