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1.
Rev Med Virol ; 33(3): e2432, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36807958

RESUMO

According to the World Health Organisation, as of October 2022, there have been 55,560,329 reported cases of SARS-COV-2 in patients under 19 years old. It is estimated that about 0.06% of these patients may develop MIS-C, representing more than 2 million children worldwide. This systematic review and meta-analysis examined the pooled prevalence of cardiovascular manifestation and cardiac complications in children hospitalised with MIS-C. The PROSPERO register number is CRD42022327212. We included case-report studies, case-control studies, cohort studies, and cross-sectional studies, as well as clinical trials or studies describing cardiac manifestations of MIS-C and its sequelae in a paediatric population. Initially, 285 studies were selected, but there were 154 duplicates, and 81 were excluded because they did not fit the eligibility criteria. Thus, 50 studies were selected for review, and 30 were included in the meta-analysis. A total sample size of 1445 children was included. The combined prevalence of myocarditis or pericarditis was 34.3% (95% CI: 25.0%-44.2%). The combined prevalence for echocardiogram anomalies was 40.8% (95% CI: 30.5%-51.5%), that of Kawasaki disease presentation was 14.8% (95% CI: 7.5%-23.7%), and that of coronary dilation was 15.2% (95% CI: 11.0%-19.8%). The rate of electrocardiogram anomalies was 5.3% (95% CI: 0.8%-12.3%), and the mortality rate was 0.5% (CI 95%: 0%-1.2%). Furthermore, 186 children still had complications at discharge, with a combined prevalence of such long-lasting manifestations of 9.3% (95% CI: 5.6%-13.7%). Studies that assess whether these children will have an increased cardiovascular risk with a greater chance of acute myocardial infarction, arrhythmias, or thrombosis will be essential for healthcare planning.


Assuntos
COVID-19 , Miocardite , Adulto , Criança , Humanos , Adulto Jovem , COVID-19/complicações , Miocardite/complicações , SARS-CoV-2
2.
Phys Chem Chem Phys ; 21(26): 14453-14464, 2019 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-31210192

RESUMO

Single photon ionization and subsequent unimolecular ion decomposition were studied on jet-cooled benzophenone and fluorenone separately, using VUV synchrotron radiation in a photoion/photoelectron coincidence setup. Slow PhotoElectron Spectra (SPES) were recorded in coincidence with either the parent or the fragment ions for hν < 12.5 eV. Dissociative ionization is observed for benzophenone only. The full interpretation of the measurements, including the identification of the neutral and ionic species when dissociative ionization is at play, benefits from high level ab initio computations for determining the equilibrium structures and the energetics of the neutral and ionized molecules and of their fragments. Electronically excited states of the parent molecular ions were calculated also. From this analysis, an accurate experimental determination of the energetics of the benzophenone and fluorenone ions and of their fragmentation channels is available: adiabatic ionization energies of benzophenone at 8.923 ± 0.005 eV and of fluorenone at 8.356 ± 0.007 eV; and appearance energies of benzophenone fragment ions at 11.04 ± 0.02 eV (loss of C6H5), 11.28 ± 0.02 eV (loss of H) and 11.45 ± 0.02 eV (loss of CO). The corresponding fragmentation mechanisms are explored, showing likely concerted bonds rearrangement. Possible pre-ionizing fragmentation is discussed in light of the spectra presented. The structural rigidity of fluorenone diarylketone seems to be the origin of the inhibition of the fragmentation of its cation.

3.
Phys Chem Chem Phys ; 20(17): 11730-11739, 2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-29687125

RESUMO

A combined theoretical and experimental approach has been used to investigate the binding energy of a ruthenium metalloporphyrin ligated with CO, ruthenium tetraphenylporphyrin [RuII TPP], in the RuII oxidation degree. Measurements performed with VUV ionization using the DESIRS beamline at Synchrotron SOLEIL led to adiabatic ionization energies of [RuII TPP] and its complex with CO, [RuII TPP-CO], of 6.48 ± 0.03 eV and 6.60 ± 0.03 eV, respectively, while the ion dissociation threshold of [RuII TPP-CO]+ is measured to be 8.36 ± 0.03 eV using the ground-state neutral complex. These experimental data are used to derive the binding energies of the CO ligand in neutral and cationic complexes (1.88 ± 0.06 eV and 1.76 ± 0.06 eV, respectively) using a Born-Haber cycle. Density functional theory calculations, in very satisfactory agreement with the experimental results, help to get insights into the metal-ligand bond. Notably, the high ligation energies can be rationalized in terms of the ruthenium orbital structure, which is singular compared to that of the iron atom. Thus, beyond indications of a strengthening of the Ru-CO bond due to the decrease in the CO vibrational frequency in the complex as compared to the Fe-CO bond, high-level calculations are essential to accurately describe the metal ligand (CO) bond and show that the Ru-CO bond energy is strongly affected by the splitting of triplet and singlet spin states in uncomplexed [Ru TPP].

4.
J Chem Phys ; 149(20): 204313, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30501230

RESUMO

The photodissociation dynamics of CH3I and CH2ClI at 272 nm were investigated by time-resolved Coulomb explosion imaging, with an intense non-resonant 815 nm probe pulse. Fragment ion momenta over a wide m/z range were recorded simultaneously by coupling a velocity map imaging spectrometer with a pixel imaging mass spectrometry camera. For both molecules, delay-dependent pump-probe features were assigned to ultraviolet-induced carbon-iodine bond cleavage followed by Coulomb explosion. Multi-mass imaging also allowed the sequential cleavage of both carbon-halogen bonds in CH2ClI to be investigated. Furthermore, delay-dependent relative fragment momenta of a pair of ions were directly determined using recoil-frame covariance analysis. These results are complementary to conventional velocity map imaging experiments and demonstrate the application of time-resolved Coulomb explosion imaging to photoinduced real-time molecular motion.

5.
Arch Virol ; 162(11): 3431-3438, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28780631

RESUMO

GB virus C (GBV-C) is a lymphotropic virus with a low level or non-existent replication in the liver. The interaction between HIV-1 and GBV-C apparently reduces the progression of HIV-1 infection to AIDS and improves the quality of life of HIV-1 infected individuals. A cross-sectional study was established to determine the possible effect of HIV-1/GBV-C coinfection on HIV-1 viral load and CD4+ T lymphocyte counts. Samples from 313 HIV-1 infected persons from the Virus Laboratory of the Federal University of Pará as well as demographic and clinical information were obtained from medical records. This study used a nested PCR method to determine GBV-C viremia. The prevalence of HIV-1/GBV-C coinfection was 17%. There were no significant differences in the distribution according to age, sex or ethnicity between the groups. The differences in HIV-1 viral load and CD4+ T lymphocyte count between the HIV-1 and HIV-1/GBV-C groups were highly significant, indicating that coinfection results in lower viral loads and higher CD4+ T lymphocyte counts compared to HIV-1 mono-infection. The results indicate a protective effect among coinfected individuals.


Assuntos
Coinfecção/virologia , Infecções por Flaviviridae/complicações , Vírus GB C , Infecções por HIV/complicações , HIV-1 , Hepatite Viral Humana/complicações , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Infecções por Flaviviridae/virologia , Infecções por HIV/virologia , Hepatite Viral Humana/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
J Chem Phys ; 147(15): 154302, 2017 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-29055295

RESUMO

The methyl carbocation is ubiquitous in gaseous environments, such as planetary ionospheres, cometary comae, and the interstellar medium, as well as combustion systems and plasma setups for technological applications. Here we report on a joint experimental and theoretical study on the mechanism of the reaction CH3+ + CH3CCCH3 (but-2-yne, also known as dimethylacetylene), by combining guided ion beam mass spectrometry experiments with ab initio calculations of the potential energy hypersurface. Such a reaction is relevant in understanding the chemical evolution of Saturn's largest satellite, Titan. Two complementary setups have been used: in one case, methyl cations are generated via electron ionization, while in the other case, direct vacuum ultraviolet photoionization with synchrotron radiation of methyl radicals is used to study internal energy effects on the reactivity. Absolute reactive cross sections have been measured as a function of collision energy, and product branching ratios have been derived. The two most abundant products result from electron and hydride transfer, occurring via direct and barrierless mechanisms, while other channels are initiated by the electrophilic addition of the methyl cation to the triple bond of but-2-yne. Among the minor channels, special relevance is placed on the formation of C5H7+, stemming from H2 loss from the addition complex. This is the only observed condensation product with the formation of new C-C bonds, and it might represent a viable pathway for the synthesis of complex organic species in astronomical environments and laboratory plasmas.

7.
J Phys Chem A ; 120(33): 6529-40, 2016 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-27471793

RESUMO

The chemical composition of Titan organic haze is poorly known. To address this issue, laboratory analogues named tholins are synthesized and analyzed by methods often requiring an extraction process in a carrier solvent. These methods exclude the analysis of the insoluble tholins' fraction and assume a hypothetical chemical equivalence between soluble and insoluble fractions. In this work, we present a powerful complementary analysis method recently developed on the DESIRS VUV synchrotron beamline at SOLEIL. It involves soft pyrolysis of tholins at ∼230 °C and electron/ion coincidence analysis of the emitted volatile compounds photoionized by tunable synchrotron radiation. By comparison with reference photoelectron spectra (PES), the spectral information collected on the detected molecules yields their isomeric structure. The method is more readily applied to light species (m/z ≤ 69), while for heavier ones, the number of possibilities and the lack of PES reference spectra in the literature limit its analysis. A notable pattern in the analyzed tholins is the presence of species containing adjacent doubly bonded N atoms, which might be a signature of heterogeneous incorporation of N2 in tholins.

8.
J Phys Chem A ; 119(23): 6082-98, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-25721439

RESUMO

An experimental study has been carried out on the reactions of state selected O(+)((4)S, (2)D, (2)P) ions with methane with the aims of characterizing the effects of both the parent ion internal energy and collision energy on the reaction dynamics and determining the fate of oxygen species in complex media, in particular the Titan ionosphere. Absolute cross sections and product velocity distributions have been determined for the reactions of (16)O(+) or (18)O(+) ions with CH4 or CD4 from thermal to 5 eV collision energies by using the guided ion beam (GIB) technique. Dissociative photoionization of O2 with vacuum ultraviolet (VUV) synchrotron radiation delivered by the DESIRS beamline at the SOLEIL storage ring and the threshold photoion photoelectron coincidence (TPEPICO) technique are used for the preparation of purely state-selected O(+)((4)S, (2)D, (2)P) ions. A complete inversion of the product branching ratio between CH4(+) and CH3(+) ions in favor of the latter is observed for excitation of O(+) ions from the (4)S ground state to either the (2)D or the (2)P metastable state. CH4(+) and CH3(+) ions, which are by far the major products for the reaction of ground state and excited states, are strongly backward scattered in the center of mass frame relative to O(+) parent ions. For the reaction of O(+)((4)S), CH3(+) production also rises with increasing collision energy but with much less efficiency than with O(+) excitation. We found that a mechanism of dissociative charge transfer, mediated by an initial charge transfer step, can account very well for all the observations, indicating that CH3(+) production is associated with the formation of H and O atoms (CH3(+) + H + O) rather than with OH formation by an hydride transfer process (CH3(+) + OH). Therefore, as the CH4(+) production by charge transfer is also associated with O atoms, the fate of oxygen species in these reactions is essentially the O production, except for the reaction of O(+)((4)S), which also produces appreciable amounts of H2O(+) ions but only at very low collision energy. The production of O atoms and the nature of the states in which they are formed are discussed for the reactions of O(+) ions with CH4 and N2.

9.
J Chem Phys ; 142(18): 184306, 2015 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-25978890

RESUMO

The threshold photoelectron spectra (TPES) of two unstable nitrogen-containing species, HNCO and NCO, were recorded utilizing vacuum ultraviolet synchrotron radiation. Both are intermediates in combustion processes and play a role in the removal of nitrogen oxides from exhaust gases. The rovibronic structure of the first band in the TPES of HNCO(+) was analyzed within the framework of an orbital ionization model, and the resolved structure of the origin band was assigned to ΔK subbands. An ionization energy of 11.602 ± 0.005 eV was determined and the vibrational structure of the cationic ground state was analyzed by a Franck-Condon fit. Low lying electronically excited states of HNCO(+) were also observed. In a second series of experiments, the NCO radical was generated by flash pyrolysis from chlorine isocyanate. The ionization energy to the X(+) (3)Σ(-) ground state was determined to be 11.76 ± 0.02 eV, while for the a(+) (1)Δ state, a value of 12.93 ± 0.02 eV was obtained. Vibrational structure was observed for both states, and bands were assigned by Franck-Condon simulations.

10.
Phys Chem Chem Phys ; 16(2): 467-76, 2014 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-24077129

RESUMO

A detailed study of the valence photoionization of small homochiral glycidol (C3O2H6) clusters is carried out with the help of circularly-polarized VUV synchrotron radiation by recording photoionization-based spectroscopic data detected by velocity map electron imaging with coincidence ion selection. We show that information on the stability of cationic as well as neutral chiral clusters can be obtained with enhanced sensitivity by examining the chiral fingerprint encapsulated in Photoelectron Circular Dichroism (PECD) spectra. In particular, by varying the clustering conditions we demonstrate that the PECD signal effectively carries the signature of the neutral precursor species, prior to any fragmentation of the ion, as may be inferred from the below-threshold monomer measurements (including ion imaging). Here the monomer's direct ionization channel is closed and the monomer ion hence must result exclusively as a fragment from dissociative ionization of the dimer (or higher) clusters. At higher photon energies, the mass-selection on the electron spectroscopy data, achieved through filtering the electron images in coincidence with selected ion masses, evidently succeeds in providing a degree of size-selection on the neutral clusters being ionized with, in particular, a clear differentiation of monomer and dimer PECD, showing the strong sensitivity of this chiroptical effect to the non-local long-range molecular potential.

11.
J Phys Chem A ; 118(47): 11185-92, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25340309

RESUMO

Gas-phase studies of biomolecules are often difficult to initiate because of the thermolability of these systems. Such studies are nevertheless important to determine fundamental intrinsic properties of the molecules. Here we present the valence shell photoionization of gas-phase vitamins A and B1 close to their ionization threshold. The study was performed by means of an aerosol thermodesorption source coupled to an electron/ion coincidence spectrometer and synchrotron radiation (SOLEIL facility, France). Ion yield curves were recorded for both molecules over a few electronvolt energy range and the threshold photoelectron spectrum was also obtained for vitamin A. Some fundamental properties were extracted for both ions such as adiabatic and the three first vertical ionization energies of retinol (IEad = 6.8 ± 0.2 eV and IEvert = 7.4, 8.3, and 9.2 eV) and dissociation appearance energies for the main fragment ions of vitamin B1. Analysis of the data was supported by ab initio calculations which show a very good agreement with the experimental observations.


Assuntos
Processos Fotoquímicos , Síncrotrons , Temperatura , Tiamina/química , Raios Ultravioleta , Vácuo , Vitamina A/química , Aerossóis , Elétrons , Gases/química , Modelos Moleculares , Conformação Molecular , Termodinâmica
12.
J Phys Chem A ; 118(15): 2765-79, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-24654892

RESUMO

The valence shell photoionization of the simplest proteinaceous chiral amino acid, alanine, is investigated over the vacuum ultraviolet region from its ionization threshold up to 18 eV. Tunable and variable polarization synchrotron radiation was coupled to a double imaging photoelectron/photoion coincidence (i(2)PEPICO) spectrometer to produce mass-selected threshold photoelectron spectra and derive the state-selected fragmentation channels. The photoelectron circular dichroism (PECD), an orbital-sensitive, conformer-dependent chiroptical effect, was also recorded at various photon energies and compared to continuum multiple scattering calculations. Two complementary vaporization methods-aerosol thermodesorption and a resistively heated sample oven coupled to an adiabatic expansion-were applied to promote pure enantiomers of alanine into the gas phase, yielding neutral alanine with different internal energy distributions. A comparison of the photoelectron spectroscopy, fragmentation, and dichroism measured for each of the vaporization methods was rationalized in terms of internal energy and conformer populations and supported by theoretical calculations. The analytical potential of the so-called PECD-PICO detection technique-where the electron spectroscopy and circular dichroism can be obtained as a function of mass and ion translational energy-is underlined and applied to characterize the origin of the various species found in the experimental mass spectra. Finally, the PECD findings are discussed within an astrochemical context, and possible implications regarding the origin of biomolecular asymmetry are identified.


Assuntos
Alanina/química , Gases/química , Fótons , Aerossóis , Processos Fotoquímicos , Espectroscopia Fotoeletrônica , Estereoisomerismo , Síncrotrons , Termodinâmica , Raios Ultravioleta , Vácuo , Volatilização
13.
Bull Environ Contam Toxicol ; 93(4): 461-4, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25168695

RESUMO

Ecotoxicity tests are key to predict environmental hazards resulting from chemical and biological pesticides in non-target species. In order to assess the effects of microbial pesticides it is important to determine if they cause infection in test organisms. At present the microbial elimination rate or clearance is not included in ecotoxicological regulatory protocols. This study evaluated the elimination of Bacillus thuringiensis and Bacillus sphaericus from fish and snails, after 30 days' exposure to commercial formulations of such entomopathogens. Data obtained showed that in clean water the tendency to eliminate microbial agents from the body of the exposed organisms is gradual over time but after 7 days the fish and snails were free of the two tested Bacillus spp.


Assuntos
Bacillus/efeitos dos fármacos , Biomphalaria/microbiologia , Characidae/microbiologia , Praguicidas/toxicidade , Peixe-Zebra/microbiologia , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/toxicidade , Toxinas Bacterianas/toxicidade , Brasil , Ensaio de Unidades Formadoras de Colônias , Ecotoxicologia , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidade
14.
J Prosthodont ; 23(7): 515-20, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24939170

RESUMO

PURPOSE: The aim of this study was to assess patients' perceptions of benefits and risks concerning complete denture therapy. A secondary objective was to assess the influence of clinical and sociodemographic variables on patients' perceptions. MATERIALS AND METHODS: The sample was composed of 104 volunteers who presented themselves for complete denture treatment at a dental school. The average age of the volunteers was 69.2 years (±) 9.3. Patient opinions concerning the benefits of complete denture therapy were recorded using a previously reported questionnaire. The answers were evaluated in three domains: (1) benefits (positive perceptions); (2) risks (negative perceptions); and (3) consequences of no treatment. RESULTS: The average time of use of the previous dentures was 20 years (SD ±12.9). Risk factors (negative perceptions) received lower scores by the patients, while the consequences of no treatment received higher scores. No association was found among evaluations of the previous dentures and educational level, marital status, and gender; however, patients' evaluation about their previous dentures was significantly different depending on age (p = 0.001) and previous dentures' time of use (p = 0.038). CONCLUSIONS: Patients presented a positive perception of complete denture therapy, and the risk factors (negative perceptions) received the lowest scores. Patient perception regarding complete denture therapy was not influenced by educational level, evaluation of the previous dentures, or marital status.


Assuntos
Atitude Frente a Saúde , Prótese Total/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Oclusão Dentária , Falha de Restauração Dentária , Retenção de Dentadura , Escolaridade , Estética Dentária , Feminino , Humanos , Masculino , Estado Civil , Pessoa de Meia-Idade , Boca Edêntula/psicologia , Satisfação do Paciente , Medição de Risco , Fatores de Risco , Fatores Sexuais , Fatores de Tempo
15.
Chempluschem ; : e202400135, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963686

RESUMO

The conversion of bioethanol to ethylene in gas phase and atmospheric pressure was investigated over γ-Al2O3 supported copper and nickel catalysts. These catalysts were prepared by co-precipitation and pre-treated with hydrogen at 450 °C. Six catalysts were studied at 450 °C under a nitrogen atmosphere. It was found that the monometallic Cu/γ-Al2O3 catalyst exhibited the highest ethylene concentration, with a selectivity of around 90%. The bioethanol conversion obtained was between 57%-86%. Another catalyst that exhibited high concentration values was the NiCu1:7 bimetallic catalyst. The catalysts were characterised using XRD, SEM, EDS, TEM, TGA, FTIR, Raman, and N2-physisoption techniques. Furthermore, the Cu/γ-Al2O3 catalyst was studied under different reduction temperatures and gas flow conditions. It was found that the catalysts reduced at 350 °C and 35 ml/min N2 flow presented ethylene concentrations between (0.18-0.21) g/L. Moreover, the catalyst deactivation was identified to be first order and the equation of the Cu/γ-Al2O3 catalyst deactivation model was determined. Carbonaceous deposits over the used sample were not detected by Raman and FTIR. It was determined that the Cu/γ-Al2O3 catalyst deactivation could be mainly attributed to the blocking of the catalytic sites by strongly adsorbed compounds and hydroxylation of the catalyst surface.

16.
Curr Pediatr Rev ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38879764

RESUMO

The Prune-Belly (Eagle-Barrett) syndrome (PBS) is a congenital and genetically heterogeneous disease, more prevalent in males, defined by the clinical triad (1) deficiency of abdominal muscles, (2) bilateral cryptorchidism, and (3) urinary tract abnormalities. The abdomen of an infant with PBS has a typical appearance, similar to the aspect of a prune, which gives it its name. Although the etiology of this disorder is still unknown, numerous theories, mutations, and genetic disturbances have been proposed to explain the origin of PBS. Prognosis can differ a lot from one patient to another, since this condition has a wide spectrum of clinical presentation. Despite being a rare condition, the importance of PBS should not be underestimated, in the light of the potential of the disorder to lead to chronic kidney disease and other severe complications. In that regard, this review gathers the most up-to-date knowledge about the etiopathogenesis, clinical features, diagnosis, management and prognosis of PBS.

18.
J Chem Phys ; 136(20): 204304, 2012 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-22667557

RESUMO

The trifluoromethyl radical, CF(3)(●), is studied for the first time by means of threshold photoelectron spectroscopy (TPES). The radical is produced in the gas phase using the flash-pyrolysis technique from hexafluoroethane as a precursor. CF(3)(+) total ion yield and mass-selected TPES of the radical are recorded using a spectrometer based upon velocity map imaging and Wiley-McLaren time-of-flight coupled to the synchrotron radiation. The high resolution of the instrument and of the photons allows the observation of rich vibrational progressions in the TPES of CF(3)(●). By using Franck-Condon factors computed by Bowman and coworkers, we have been able to simulate the TPES. The initial vibrational temperature of the radical beam has been evaluated at 350 ± 70 K. The structures have been identified as transitions between (n(1),n(2)) and (n(1)(+),n(2)(+)) vibrational levels of CF(3) and CF(3)(+) with small excitation of the breathing mode, ν(1)(+) (,) and large excitation (n(2)(+) = 10-26) of the umbrella mode, ν(2)(+), in the cation. From the energy separation between the two resolved peaks of each band, a value of 994 ± 16 cm(-1) has been derived for the ν(1)(+) breathing frequency of CF(3)(+). For the high-lying n(2)(+) levels, the apparent ν(2)(+) umbrella spacing, 820 ± 14 cm(-1), is fairly constant. Taking into account the ν(2)(+) anharmonicity calculated by Bowman and coworkers, we have deduced ν(2)(+) = 809 ± 14 cm(-1), and semi-empirical estimations of the adiabatic ionization energy IE(ad.)(CF(3)(●)) are proposed in good agreement with most of previous works. A value of the vertical ionization potential, IE(vert.)(CF(3)(●)) = 11.02 eV, has been derived from the observation of a photoelectron spectrum recorded at a fixed photon energy of 12 eV.

19.
Arq Bras Cir Dig ; 34(4): e1626, 2022.
Artigo em Português, Inglês | MEDLINE | ID: mdl-35107488

RESUMO

OBJECTIVE: Nonalcoholic fatty liver disease (NAFLD) is considered a public health problem, mainly in severely obese patients. The aim of the present study was to investigate different biochemical-based scores available and determine which one could best serve as an NAFLD predicting tool in a severely obese population. METHODS: This was a cross-sectional study involving severely obese patients. All patients were evaluated with serum laboratory parameters for 1 week before biopsy, and all patients were treated with intraoperative liver biopsy, during bariatric surgery. RESULTS: A total of 143 severely obese patients were included. The median body mass index (BMI) was 48 kg/m2 (35-65). Diabetes mellitus was present in 36%, and steatosis was present in 93% (severe steatosis in 20%). Only aspartate transaminase (AST) to platelet ratio index (APRI=0.65 (95% CI: 0.55-0.8) and homeostatic model assessment for insulin resistance (HOMA-IR=0.7 (95% CI: 0.58-0.82) showed significant capacity for the prediction of severe steatosis. Hepatic steatosis index (HSI), NAFLD fibrosis score (NAFLDS), alanine aminotransferase (ALT)/AST, and fibrosis-4 (FIB-4) were not able to correctly predict severe steatosis on liver biopsy. APRI showed high specificity of 82% and low sensitivity of 54%. In contrast, HOMA-IR showed high sensitivity of 84% and low specificity of 48%. CONCLUSIONS: NAFLDS, FIB-4, AST/ALT, and HSI have no utility for the evaluation of severe steatosis in severely obese patients. Diabetes and insulin-resistance-related biochemical assessments, such as HOMA-IR, can be used as good screening tools for severe steatosis in these patients. APRI score is the most specific biochemical diagnostic tool for steatosis in severely obese patients and can help clinicians to decide the need for bariatric or metabolic surgery.


OBJETIVOS: A doença hepática gordurosa não-alcoólica já é considerada um problema de saúde pública, principalmente em pacientes com obesidade severa. O objetivo do presente estudo foi investigar os diferentes escores de bioquímiosa disponíveis e determinar qual deles poderia servir melhor como uma ferramenta de avaliação da NAFLD em uma população de obesos. MÉTODOS: Este é um estudo transversal de pacientes obesos. Todos os pacientes foram avaliados com parâmetros laboratoriais séricos 1 semana antes da biópsia e todos os pacientes foram submetidos a biópsia hepática intra-operatória, durante a cirurgia bariátrica. RESULTADOS: Cento e quarenta e três pacientes obesos foram incluídos. Apenas APRI (0,65; IC 95%: 0,55 a 0,8) e HOMA-IR (0,7; IC 95%: 0,58 a 0,82) mostraram capacidade significativa de predição de esteatose grave. HSI, NALFDS, ALS / AST e FIB-4 não foram capazes de prever corretamente esteatose grave na biópsia hepática. APRI mostrou alta especificidade (82%) e baixa sensibilidade (54%). Em contraste, o HOMA-IR apresentou alta sensibilidade (84%) e baixa especificidade (48%). CONCLUSÃO: O NALFDS, FIB-4, AST / ALT e HSI não têm utilidade para avaliação de esteatose grave em pacientes com obesidade severa. Diabetes e avaliação bioquímica relacionada à resistência à insulina, como o HOMA-IR, podem ser empregados como boas ferramentas de rastreamento para esteatose grave em tais pacientes. O escore APRI é a ferramenta diagnóstica bioquímica mais específica para esteatose em pacientes com obesidade severa e pode ser empregado, por equipes médicas, para auxiliar na indicação de cirurgia bariátrica ou metabólica.


Assuntos
Cirurgia Bariátrica , Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Estudos Transversais , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Obesidade
20.
Phys Chem Chem Phys ; 13(40): 17956-9, 2011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-21931930

RESUMO

The photoionisation of the C(3)H(2) isomer propargylene was studied using synchrotron radiation and coincidence techniques. An adiabatic ionisation energy (IE(ad)) of 8.99 ± 0.02 eV was determined. The precursor diazopropyne was investigated as well. Ionisation and appearance energies were measured.

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