The Electroionization Spectrum of Nitric Oxide

1974 ◽  
Vol 52 (19) ◽  
pp. 1885-1890 ◽  
Author(s):  
R. Carbonneau ◽  
P. Marmet
Keyword(s):  
Nitric Oxide ◽  
Rydberg States ◽  
Negative Ion ◽  
Electron Transmission ◽  
First Time ◽  
Π State

Negative ion resonances having the NO+b3Π, A1Π, c3Π, and B1Π states as grandparents are observed for the first time in the electroionization spectrum of NO. Our results are compared with those from electron transmission experiments. Moreover, some Rydberg states from the series converging to the NO+b3Π state have been analyzed.

Negative and Neutral Autoionizing States Detected in the Electroionization Curve in CO

1973 ◽  
Vol 51 (20) ◽  
pp. 2202-2208 ◽  
Author(s):  
R. Carbonneau ◽  
P. Marmet
Keyword(s):  
Excited States ◽  
Rydberg States ◽  
Negative Ion ◽  
Electron Transmission ◽  
Doubly Excited States ◽  
Doubly Excited ◽  
First Time ◽  
Autoionizing States

Negative ion resonances and neutral Rydberg states having the A2Π and B2Σ+ states of CO+ as limits are reported for the first time in the electroionization curve of CO. Moreover, new doubly excited states of CO are observed around 21 eV. The electroionization is compared with photoionization, photoabsorption, and electron transmission when data are available.

Increasing dihydrobiopterin causes dysfunction of endothelial nitric oxide synthase in rats in vivo

2011 ◽  
Vol 301 (3) ◽  
pp. H721-H729 ◽  
Author(s):  
Katsuhiko Noguchi ◽  
Naobumi Hamadate ◽  
Toshihiro Matsuzaki ◽  
Mayuko Sakanashi ◽  
Junko Nakasone ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Endothelial Nitric Oxide Synthase ◽  
Control Treatment ◽  
Enos Uncoupling ◽  
Nos Inhibitor ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide ◽  
First Time

An elevation of oxidized forms of tetrahydrobiopterin (BH4), especially dihydrobiopterin (BH2), has been reported in the setting of oxidative stress, such as arteriosclerotic/atherosclerotic disorders, where endothelial nitric oxide synthase (eNOS) is dysfunctional, but the role of BH2 in the regulation of eNOS activity in vivo remains to be evaluated. This study was designed to clarify whether increasing BH2 concentration causes endothelial dysfunction in rats. To increase vascular BH2 levels, the BH2 precursor sepiapterin (SEP) was intravenously given after the administration of the specific dihydrofolate reductase inhibitor methotrexate (MTX) to block intracellular conversion of BH2 to BH4. MTX/SEP treatment did not significantly affect aortic BH4 levels compared with control treatment. However, MTX/SEP treatment markedly augmented aortic BH2 levels (291.1 ± 29.2 vs. 33.4 ± 6.4 pmol/g, P < 0.01) in association with moderate hypertension. Treatment with MTX alone did not significantly alter blood pressure or BH4 levels but decreased the BH4-to-BH2 ratio. Treatment with MTX/SEP, but not with MTX alone, impaired ACh-induced vasodilator and depressor responses compared with the control treatment (both P < 0.05) and also aggravated ACh-induced endothelium-dependent relaxations ( P < 0.05) of isolated aortas without affecting sodium nitroprusside-induced endothelium-independent relaxations. Importantly, MTX/SEP treatment significantly enhanced aortic superoxide production, which was diminished by NOS inhibitor treatment, and the impaired ACh-induced relaxations were reversed with SOD ( P < 0.05), suggesting the involvement of eNOS uncoupling. These results indicate, for the first time, that increasing BH2 causes eNOS dysfunction in vivo even in the absence of BH4 deficiency, demonstrating a novel insight into the regulation of endothelial function.

NO nerves in a tapeworm. NADPH-diaphorase histochemistry in adult Hymenolepis diminuta

Parasitology ◽  
1996 ◽  
Vol 113 (6) ◽  
pp. 559-565 ◽  
Author(s):  
M. K. S. Gustafsson ◽  
A. M. Lindholm ◽  
N. B. Terenina ◽  
M. Reuter
Keyword(s):  
Nitric Oxide ◽  
Nervous System ◽  
Nadph Diaphorase ◽  
Hymenolepis Diminuta ◽  
Staining Reaction ◽  
Internal Seminal Vesicle ◽  
Oxide Synthase ◽  
First Time ◽  
The Brain ◽  
Nerve Cords

SUMMARYThe free radical nitric oxide (NO), which is synthesized by nitric oxide synthase (NOS), has recently been discovered to function as a neuronal messenger. The presence of NOS was detected in the nervous system of adult Hymenolepis diminuta with NADPH-diaphorase (NADPH-d) histochemistry. The NADPH-d histochemical reaction is regarded as a selective marker for NOS in neuronal tissue. NADPH-d staining was observed in nerve fibres in the main and minor nerve cords and the transverse ring commissures, and in cell bodies in the brain commissure, along the main nerve cords, in the suckers and the rostellar sac. NADPH-d staining was also observed in the wall of the internal seminal vesicle and the genital atrium. The pattern of NADPH-d staining was compared with that of the 5-HT immunoreactive nervous elements. The NADPH-d staining reaction and the 5-HT immunoreactivity occur in separate sets of neurons. This is the first time the NADPH-d reaction has been demonstrated in the nervous system of a flatworm, indicating that NOS is present and that NO can be produced at this level of evolution.

Abstract 18060: TRAIL Promotes Angiogenesis and Ischemia-Induced Neovascularisation via NOX4, H2O2 and Nitric Oxide-Dependent Mechanisms

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Belinda A Di Bartolo ◽  
Sian P Cartland ◽  
Leonel Prado-Lourenco ◽  
Nor Saadah M Azahri ◽  
Thuan Thai ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Angiogenic Factor ◽  
Tubule Formation ◽  
Nitric Oxide Synthase Inhibitor ◽  
Therapeutic Implications ◽  
Synthase Inhibitor ◽  
Oxide Synthase ◽  
First Time

Background: Angiogenesis and neovascularization are essential processes that follow ischemia insults. Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) not only induces endothelial cell (EC) death and inhibits angiogenesis, but also promotes EC migration, invasion and proliferation in vitro . These seemingly opposite effects make its role in angiogenesis in vivo unclear. Using TRAIL -/- and wild-type mice, we sought to determine the role of TRAIL in angiogenesis and neovascularisation. We also sought mechanisms in vitro . Methods and Results: Reduced vascularisation assessed by real-time in vivo 3D Vevo ultrasound imaging and CD31 staining was observed in TRAIL -/- mice 28 d after hindlimb ischemia. Moreover, reduced capillary formation and increased apoptosis was evident in TRAIL -/- muscles even at 3 d after ischemic surgery. We have previously shown that fibroblast growth factor-2 (FGF-2), a potent angiogenic factor, regulates TRAIL gene expression in vascular smooth muscle cells. Indeed, FGF-2 also regulates TRAIL expression in ECs, and FGF-2-inducible proliferation, migration and tubule formation was inhibited with siRNA targeting TRAIL. Notably, both FGF-2 and TRAIL significantly increased NOX4 expression. TRAIL-inducible angiogenic activity in ECs was inhibited with siRNAs targeting NOX4, and consistent with these, NOX4 mRNA was reduced in 3 d ischemic hindlimbs of TRAIL -/- mice. TRAIL stimulated intracellular H 2 O 2 levels in ECs, and TRAIL-inducible proliferation, migration and tubule formation was inhibited with not only PEG-catalase, a H 2 O 2 scavenger, but also blocked with L-NAME, a nitric oxide synthase inhibitor. Conclusions: This is the first demonstration showing that TRAIL promotes angiogenesis in vivo . We show for the first time that the TRAIL stimulates NOX4 expression to mediate nitric oxide-dependent angiogenic effects. This has significant therapeutic implications such that TRAIL may improve the angiogenic response to ischemia and increase perfusion recovery in patients with CVD and diabetes.

Intense exercise causes decrease in expression of both endothelial NO synthase and tissue NOx level in hearts

2000 ◽  
Vol 279 (3) ◽  
pp. R951-R959 ◽  
Author(s):  
Motoyuki Iemitsu ◽  
Takashi Miyauchi ◽  
Seiji Maeda ◽  
Koichi Yuki ◽  
Tsutomu Kobayashi ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Heart Rate ◽  
Mrna Level ◽  
Tissue Level ◽  
No Synthase ◽  
Adrenergic Stimulation ◽  
Intense Exercise ◽  
End Products ◽  
First Time ◽  
Enos Protein

Cardiac myocytes produce nitric oxide (NO). We studied the effects of intense exercise on the expression of NO synthase (NOS) and the tissue level of nitrite (NO2 −)/nitrate (NO3 −) (i.e., NOx), which are stable end products of NO in the heart. Rats ran on a treadmill for 45 min. Immediately after this exercise, the heart was quickly removed. Control rats remained at rest during the same 45-min period. The mRNA level of endothelial NOS (eNOS) in the heart was markedly lower in the exercised rats than in the control rats. Western blot analysis confirmed downregulation of eNOS protein in the heart after exercise. Tissue NOx level in the heart was significantly lower in the exercised rats than in the control rats. The present study revealed for the first time that production of NO in the heart is decreased by intense exercise. Because NO attenuates positive inotropic and chronotropic responses to β1-adrenergic stimulation in the heart, the decrease in cardiac production of NO by intense exercise may contribute to the acceleration of increase in myocardial contractility and heart rate during intense exercise.

scholarly journals Rapid Characterizaiton of Chemical Constituents of the Tubers of Gymnadenia conopsea by UPLC–Orbitrap–MS/MS Analysis

Molecules ◽  
2020 ◽  
Vol 25 (4) ◽  
pp. 898
Author(s):  
Xin Wang ◽  
Xiang-Jian Zhong ◽  
Na Zhou ◽  
Ning Cai ◽  
Jia-Hui Xu ◽  
...  
Keyword(s):  
Phenolic Acid ◽  
High Performance ◽  
Chemical Constituents ◽  
Scientific Basis ◽  
Negative Ion ◽  
Chemical Components ◽  
Gymnadenia Conopsea ◽  
Orbitrap Mass Spectrometer ◽  
First Time ◽  
Orbitrap Ms

Gymnadenia conopsea R. Br. is a traditional Tibetan medicinal plant that grows at altitudes above 3000 m, which is used to treat neurasthenia, asthma, coughs, and chronic hepatitis. However, a comprehensive configuration of the chemical profile of this plant has not been reported because of the complexity of its chemical constituents. In this study, a rapid and precise method based on ultra-high performance liquid chromatography (UPLC) combined with an Orbitrap mass spectrometer (UPLC–Orbitrap–MS/MS) was established in both positive- and negative-ion modes to rapidly identify various chemical components in the tubers of G. conopsea for the first time. Finally, a total of 91 compounds, including 17 succinic acid ester glycosides, 9 stilbenes, 6 phenanthrenes, 19 alkaloids, 11 terpenoids and steroids, 20 phenolic acid derivatives, and 9 others, were identified in the tubers of G. conopsea based on the accurate mass within 3 ppm error. Furthermore, many alkaloids, phenolic acid derivates, and terpenes were reported from G. conopsea for the first time. This rapid method provides an important scientific basis for further study on the cultivation, clinical application, and functional food of G. conopsea.

scholarly journals Analysis of Major Chemical Constituents in Luan-Pao-Prescription Using Liquid Chromatography Coupled with Electrospray Ionization Mass Spectrometry

2008 ◽  
Vol 3 (5) ◽  
pp. 1934578X0800300
Author(s):  
Jin-qiang Zhang ◽  
Min Yang ◽  
Bao-hong Jiang ◽  
Hui-lian Huang ◽  
Guang-tong Chen ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Electrospray Ionization ◽  
Chemical Constituents ◽  
Negative Ion ◽  
Female Sterility ◽  
Ionization Mass ◽  
Chinese Herbal ◽  
Major Chemical ◽  
First Time

Luan-Pao-Prescription is a famous Chinese herbal formula, which is commonly used for the treatment of female sterility in clinical practice in China. In the present paper, a reliable method based on liquid chromatography coupled with electrospray ionization tandem mass spectrometry in both positive and negative ion modes has been established for the analysis of major chemical constituents in Luan-Pao-Prescription. A total of 34 compounds were either identified or tentatively characterized. These compounds include flavonoids, anthraquinones, iridoids, xanthones and organic acids. Flavonoids were the major constituents of the formula. The results profiled the chemical composition of Luan-Pao-Prescription comprehensively for the first time.

Spectroscopie d'électroionisation de HBr et DBr entre 11 et 25 eV

1985 ◽  
Vol 63 (8) ◽  
pp. 1015-1021 ◽  
Author(s):  
Paul Marmet ◽  
Hamid K. Nasrallah
Keyword(s):  
Rydberg States ◽  
Ionization Threshold ◽  
Negative Ion

Electroionization spectra of HBr and DBr are measured and analyzed between the ionization threshold and 25 eV. Several negative-ion states having configurations (4pσ) (4pπ)4 5s2, 5p2, and 4d2, associated with Rydberg states converging to the 2Σ+ limit, have been identified. Other structures result from the excitation of the inner 4sσ electron. Finally, data on DBr are used to confirm the interpretation.

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