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1.
World J Biol Psychiatry ; 23(1): 67-77, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33949291

RESUMO

OBJECTIVES: This study examined cognition-immune interactions, specifically executive function, working memory, peripheral levels of tumour necrosis factor-alpha (TNF-α), and soluble tumour necrosis factor receptors-1 and -2 (sTNFR1 and 2) levels in bipolar disorder (BD) patients in comparison with controls. METHODS: Thirty-one BD participants and twenty-seven controls participated in the study. The neurocognitive assessment was performed through three of CogState Research BatteryTM tasks for executive function and working memory. Plasma levels of TNF-α, sTNFR1, and sTNFR2 were measured after overnight fasting. Sociodemographic data and symptom severity of depression and mania were assessed. RESULTS: BD presented a significantly worse performance in the working memory task (p = .005) and higher levels of TNF-α (p = .043) in comparison to controls. A trend level of significance was found for sTNFR1 between groups (p = .082). Among BD participants, there were significant correlations between sTNFR2 and neurocognitive tasks (Groton Maze Learning Task: ρ = .54, p = .002; Set-Shifting Task: ρ = .37, p = .042; and the Two-Back Task: ρ = -.49, p = .005), and between sTNFR1 and mania, depression and anxiety symptoms (respectively ρ = .37, p = .038; ρ = -.38, p = .037; and ρ = .42, p = .002). CONCLUSION: TNF-α and its receptors might be an important variable in cognitive impairment in BD. Future studies might focus on the development of anti-inflammatory therapeutic targets for cognitive dysfunction in BD.


Assuntos
Transtorno Bipolar , Função Executiva , Memória de Curto Prazo , Fator de Necrose Tumoral alfa , Transtorno Bipolar/imunologia , Cognição , Humanos , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral
2.
Braz. J. Psychiatry (São Paulo, 1999, Impr.) ; 42(5): 519-526, Sept.-Oct. 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1132116

RESUMO

Objective: This randomized controlled trial examined the efficacy and safety of N-acetylcysteine as an adjunctive treatment for smoking cessation. Methods: Heavy smokers were recruited from smoking cessation treatment for this 12- week randomized controlled trial. Eligible tobacco use disorder outpatients (n=34) were randomized to N-acetylcysteine or placebo plus first-line treatment. Abstinence was verified by exhaled carbon monoxide (COexh). The assessment scales included the Fagerström Test for Nicotine Dependence, the Hamilton Depression Rating Scale, the Hamilton Anxiety Rating Scale, the Minnesota Nicotine Withdrawal Scale, and the Medication Adherence Rating Scale. We also assessed anthropometrics, blood pressure, lipid profile, and soluble tumor necrosis factor receptor (sTNF-R) levels 1 and 2. Results: First-line treatment for smoking cessation plus adjunctive N-acetylcysteine or placebo significantly reduced COexh (p < 0.01). In the N-acetylcysteine group, no significant changes were found in nicotine withdrawal symptoms, depressive and anxiety symptoms, anthropometric measures, blood pressure, or glucose compared to placebo. However, there was a significant reduction in sTNF-R2 levels between baseline and week 12 in the N-acetylcysteine group. Conclusions: These findings highlight the need to associate N-acetylcysteine with first-line treatment for smoking cessation, since combined treatment may affect inflammation and metabolism components. Clinical trial registration: NCT02420418


Assuntos
Humanos , Tabagismo , Abandono do Hábito de Fumar , Acetilcisteína/uso terapêutico , Método Duplo-Cego , Resultado do Tratamento , Nicotina
3.
Braz J Psychiatry ; 42(5): 519-526, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32725102

RESUMO

OBJECTIVE: This randomized controlled trial examined the efficacy and safety of N-acetylcysteine as an adjunctive treatment for smoking cessation. METHODS: Heavy smokers were recruited from smoking cessation treatment for this 12- week randomized controlled trial. Eligible tobacco use disorder outpatients (n=34) were randomized to N-acetylcysteine or placebo plus first-line treatment. Abstinence was verified by exhaled carbon monoxide (COexh). The assessment scales included the Fagerström Test for Nicotine Dependence, the Hamilton Depression Rating Scale, the Hamilton Anxiety Rating Scale, the Minnesota Nicotine Withdrawal Scale, and the Medication Adherence Rating Scale. We also assessed anthropometrics, blood pressure, lipid profile, and soluble tumor necrosis factor receptor (sTNF-R) levels 1 and 2. RESULTS: First-line treatment for smoking cessation plus adjunctive N-acetylcysteine or placebo significantly reduced COexh (p < 0.01). In the N-acetylcysteine group, no significant changes were found in nicotine withdrawal symptoms, depressive and anxiety symptoms, anthropometric measures, blood pressure, or glucose compared to placebo. However, there was a significant reduction in sTNF-R2 levels between baseline and week 12 in the N-acetylcysteine group. CONCLUSIONS: These findings highlight the need to associate N-acetylcysteine with first-line treatment for smoking cessation, since combined treatment may affect inflammation and metabolism components. CLINICAL TRIAL REGISTRATION: NCT02420418.


Assuntos
Abandono do Hábito de Fumar , Tabagismo , Acetilcisteína/uso terapêutico , Método Duplo-Cego , Humanos , Nicotina , Resultado do Tratamento
4.
Phys Rev Lett ; 123(6): 063401, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31491183

RESUMO

We present an experimental scheme that combines the well-established method of velocity-map imaging with a cold trapped metastable neon target. The device is used for obtaining the branching ratios and recoil-ion energy distributions for the penning ionization process in optical collisions of ultracold metastable neon. The potential depth of the highly excited dimer potential is extracted and compared with theoretical calculations. The simplicity to construct, characterize, and apply such a device makes it a unique tool for the low-energy nuclear physics community, enabling opportunities for precision measurements in nuclear decays of cold, trapped, short-lived radioactive isotopes.

5.
Nat Commun ; 9(1): 912, 2018 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-29500438

RESUMO

Isomerization and carbon chemistry in the gas phase are key processes in many scientific studies. Here we report on the isomerization process from linear [Formula: see text] to its monocyclic isomer. [Formula: see text] ions were trapped in an electrostatic ion beam trap and then excited with a laser pulse of precise energy. The neutral products formed upon photoexcitation were measured as a function of time after the laser pulse. It was found using a statistical model that, although the system is excited above its isomerization barrier energy, the actual isomerization from linear to monocyclic conformation takes place on a very long time scale of up to hundreds of microseconds. This finding may indicate a general phenomenon that can affect the interstellar medium chemistry of large molecule formation as well as other gas phase processes.

6.
Phys Rev Lett ; 119(10): 103202, 2017 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-28949158

RESUMO

Autoresonance (AR) cooling of a bunch of ions oscillating inside an electrostatic ion beam trap is demonstrated for the first time. The relatively wide initial longitudinal velocity distribution is reduced by at least an order of magnitude using AR acceleration and ramping forces. The hot ions escaping the bunch are not lost from the system but continue to oscillate in the trap outside of the bunch and may be further cooled by successive AR processes. Ion-ion collisions inside the bunch close to the turning points in the trap's mirrors contribute to the thermalization of the ions. This cooling method can be applied to any mass and any charge.

7.
Rev Sci Instrum ; 88(5): 053101, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28571459

RESUMO

A Velocity Map Imaging (VMI) spectrometer has been designed and integrated with an electrostatic ion beam trap to study delayed electron emission from trapped polyatomic anions upon photodetachment. The VMI spectrometer is small in size and can record a wide range of photoelectron energies, with variable magnification. Delayed electron emission can be recorded in our experimental setup for any time duration after the photoexcitation of the polyatomic anions. Experiments were carried out with trapped O- and C5- ions to demonstrate the capability of the spectrometer. Delayed electron emissions from C5- as well as prompt photoelectrons from O- were detected by the VMI spectrometer upon photoexcitation. The design and performance of the spectrometer are presented in detail.

8.
Rev Sci Instrum ; 87(11): 113302, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910333

RESUMO

Ions in an ion bunch trapped inside an Electrostatic Ion Beam Trap (EIBT) exhibit collective oscillations within the bunch under the influence of an external driving force. These internal oscillations have been measured explicitly using a new method with a particle detector outside the EIBT. In this approach, the evolving ion bunch is monitored along the entire trap length, in contrast to the localized single point measurements that are often carried out in other techniques. In the present study, quadrupole oscillations have been measured for the first time in an EIBT along with the dipole oscillations that were measured previously. The frequency of the quadrupole oscillation is found to be about twice the dipole oscillation frequency. This is in agreement with the prediction of a theoretical model.

9.
Rev Sci Instrum ; 87(6): 063115, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27370434

RESUMO

An electrostatic cryogenic storage ring, CSR, for beams of anions and cations with up to 300 keV kinetic energy per unit charge has been designed, constructed, and put into operation. With a circumference of 35 m, the ion-beam vacuum chambers and all beam optics are in a cryostat and cooled by a closed-cycle liquid helium system. At temperatures as low as (5.5 ± 1) K inside the ring, storage time constants of several minutes up to almost an hour were observed for atomic and molecular, anion and cation beams at an energy of 60 keV. The ion-beam intensity, energy-dependent closed-orbit shifts (dispersion), and the focusing properties of the machine were studied by a system of capacitive pickups. The Schottky-noise spectrum of the stored ions revealed a broadening of the momentum distribution on a time scale of 1000 s. Photodetachment of stored anions was used in the beam lifetime measurements. The detachment rate by anion collisions with residual-gas molecules was found to be extremely low. A residual-gas density below 140 cm(-3) is derived, equivalent to a room-temperature pressure below 10(-14) mbar. Fast atomic, molecular, and cluster ion beams stored for long periods of time in a cryogenic environment will allow experiments on collision- and radiation-induced fragmentation processes of ions in known internal quantum states with merged and crossed photon and particle beams.

10.
Phys Chem Chem Phys ; 17(12): 7670-5, 2015 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-25606820

RESUMO

High sensitivity photodetachment cross-section measurements of SF6(-) are performed near the adiabatic threshold limit. The extraction of adiabatic detachment energy (ADE) from the high sensitivity measurement of the cross-section change as a function of photon energy is discussed. Below the vertical detachment energy a steep 4 orders of magnitude cross-section drop is observed, with cross sections as low as 2 × 10(-6) Å(2) measured for photon energies below 2 eV. The cross-section is fitted with both the expected spectral shape based on recently calculated Frank-Condon overlaps and a phenomenological threshold function. The resulting 1.7 ± 0.02 eV ADE values are significantly higher than previously recommended experimental ADE values obtained based on kinetics modeling, and possible differences between the experimental approaches are discussed.

11.
Rev Sci Instrum ; 84(5): 053106, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23742531

RESUMO

We describe a technique to measure absolute photo-induced cross sections for cluster anions stored in an electrostatic ion beam trap (EIBT) with a central deflector. The setup allows determination of total photo-destruction cross sections as well as partial cross sections for fragmentation and electron detachment. The unique properties of this special EIBT setup are investigated and illustrated using small Al(n)(-) clusters.

12.
Phys Rev Lett ; 107(19): 193003, 2011 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-22181602

RESUMO

We present the results of a Coulomb explosion experiment that allows for the imaging of the rovibrational wave function of the metastable H2- ion. Our measurements confirm the predicted large internuclear separation of 6 a.u., and they show that the ion decays by autodetachment rather than by spontaneous dissociation. Imaging of the resulting H2 products reveals a large angular momentum of J = 25 ± 2, quantifying the rotation that leads to the metastability of this most fundamental molecular anion.

13.
Phys Rev Lett ; 105(10): 103202, 2010 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-20867518

RESUMO

Individual product channels in the dissociative recombination of deuterated hydronium ions and cold electrons are studied in an ion storage ring by velocity imaging using spatial and mass-sensitive detection of the neutral reaction fragments. Initial and final molecular excitation are analyzed, finding the outgoing water molecules to carry internal excitation of more than 3 eV in 90% of the recombination events. Initial rotation is found to be substantial and in three-body breakup strongly asymmetric energy repartition among the deuterium products is enhanced for hot parent ions.

14.
Rev Sci Instrum ; 81(5): 055105, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20515170

RESUMO

We report on the realization and operation of a fast ion beam trap of the linear electrostatic type employing liquid helium cooling to reach extremely low blackbody radiation temperature and residual gas density and, hence, long storage times of more than 5 min which are unprecedented for keV ion beams. Inside a beam pipe that can be cooled to temperatures <15 K, with 1.8 K reached in some locations, an ion beam pulse can be stored at kinetic energies of 2-20 keV between two electrostatic mirrors. Along with an overview of the cryogenic trap design, we present a measurement of the residual gas density inside the trap resulting in only 2 x 10(3) cm(-3), which for a room temperature environment corresponds to a pressure in the 10(-14) mbar range. The device, called the cryogenic trap for fast ion beams, is now being used to investigate molecules and clusters at low temperatures, but has also served as a design prototype for the cryogenic heavy-ion storage ring currently under construction at the Max-Planck Institute for Nuclear Physics.


Assuntos
Transferência de Energia , Congelamento , Íons , Manejo de Espécimes/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
15.
Phys Rev Lett ; 105(25): 253003, 2010 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-21231587

RESUMO

Photofragmentation of the protonated water dimer H+(H2O)_{2}, a fundamental system both in aqueous solutions and gas-phase water clusters, has been studied at 13.8 nm using the Free Electron Laser FLASH in Hamburg. In a crossed-beam experiment using time-resolved, single-molecule fragment imaging, the two-body breakup into H2O++H3O+ was found as a prominent fragmentation channel with a kinetic energy release of up to 10 eV. This channel was observed with at least a similar yield as events with stronger fragmentation, producing protons together with neutral fragments and showing an absolute cross section of (0.5 ± 0.2) × 10(-18) cm2.

16.
Phys Rev Lett ; 102(22): 223202, 2009 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-19658863

RESUMO

Merging an HD+ beam with velocity matched electrons in a heavy ion storage ring we observed rapid cooling of the rotational excitations of the HD+ ions by superelastic collisions (SEC) with the electrons. The cooling process is well described using theoretical SEC rate coefficients obtained by combining the molecular R-matrix approach with the adiabatic nuclei rotation approximation. We verify the DeltaJ=-2 SEC rate coefficients, which are predicted to be dominant as opposed to the DeltaJ=-1 rates and to amount to (1-2)x10;{-6} cm;{3} s;{-1} for initial angular momentum states with J< or =7, to within 30%.

17.
Rev Sci Instrum ; 79(8): 083110, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19044339

RESUMO

We describe a bent electrostatic ion beam trap in which cluster ions of several keV kinetic energy can be stored on a V-shaped trajectory by means of an electrostatic deflector placed between two electrostatic mirrors. While maintaining all the advantages of its linear counterpart [Zajfman et al., Phys. Rev. A 55, R1577 (1997); Dahan et al., Rev. Sci. Instrum. 69, 76 (1998)], such as long storage times, straight segments, and a field-free region for merged or crossed beam experiments, the bent trap allows for simultaneous measurement of charged and neutral fragments and determination of the average kinetic energy released in the fragmentation. These unique properties of the bent trap are illustrated by first results concerning the competition between delayed fragmentation and ionization of Al(n) (-) clusters after irradiation by a short laser pulse.

18.
Phys Rev Lett ; 98(22): 223202, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17677841

RESUMO

Molecular photofragmentation has been studied by event imaging on HeH+ ions at 32 nm (38.7 eV) in a fast ion beam crossed with the free-electron laser in Hamburg (FLASH), analyzing neutral He product directions and energies. Fragmentation into He(1snl,n > or = 2)+H+ was observed to yield significant photodissociation at 32 nm with an absolute cross section of (1.4+/-0.7) x 10(-18) cm2, releasing energies of 10-20 eV. A clear dominance of photodissociation perpendicular to the laser polarization was found in contrast to the excitation paths so far emphasized in theoretical studies.

19.
Phys Rev Lett ; 93(6): 063402, 2004 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-15323629

RESUMO

The cross sections for electron detachment of internally cold Cn- and Aln- clusters were measured using an electrostatic ion beam trap fitted with an internal electron target. The measured electron-impact detachment cross sections for the Cn- (n = 1-9) clusters exhibit even-odd oscillations reflecting the binding energy trend, namely, higher cross sections for weaker binding. Surprisingly, however, these cross sections increase on the average with cluster size, n, in spite of the increase in electron binding. In contrast, the Aln- (n = 2-5) clusters follow the known scaling laws for electron detachment. We suggest that the size-dependent polarizability of these clusters is responsible for the observed behavior.

20.
Phys Rev Lett ; 91(14): 143201, 2003 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-14611521

RESUMO

We demonstrate that the dissociative recombination of D2H+ with low-energy electrons depends on the rotational energy of the molecular ion such that highly excited ions have a larger rate coefficient than colder ones. Observations on an ion beam continuously interacting with electrons at low relative velocity indicate that excited rotational levels are preferentially depleted which, in competition with radiative heating due to blackbody radiation, provides an opportunity for controlling the rotational temperature of stored molecules.

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