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1.
Artigo em Inglês | MEDLINE | ID: mdl-38928938

RESUMO

This research aimed to explore factors associated with the fear of falling (FOF) among community-dwelling older adults in Vietnam. A cross-sectional study was conducted in five communes in Soc Son, Hanoi, Vietnam, from March to June 2017. We recruited a total of 487 participants, which provided sufficient data for analysis. The outcome variable was fear of falling. Several covariates, including demographics, medical history, general health status, geriatric syndromes, eye diseases, assessment of fall risk environment, timed up-and-go test, and number of standing up in 30 s, were collected. A multivariable logistic regression model was performed to determine predictors associated with FOF. The results showed that 54.6% of the participants had FOF. Furthermore, the logistic multivariable regression model revealed several factors associated with FOF among participants in the research sites, including polypharmacy status (OR: 1.79; 95%CI 1.07-2.99), higher scores in quality of life according to the EQ-5D-5L index (OR:6.27; 95%CI: 2.77-14.17), and having fallen during the past 12 months (OR:4.4; 95%CI: 2.39-8.11). These findings contribute to a comprehensive understanding of the intricate relationship between FOF and several associated factors, notably polypharmacy status, quality of life, and having a fall during the past 12 months.


Assuntos
Acidentes por Quedas , Medo , População Rural , Humanos , Acidentes por Quedas/estatística & dados numéricos , Idoso , Vietnã , Masculino , Feminino , Medo/psicologia , Estudos Transversais , População Rural/estatística & dados numéricos , Idoso de 80 Anos ou mais , Vida Independente/psicologia , Qualidade de Vida , Fatores de Risco , Pessoa de Meia-Idade
2.
J Phys Chem A ; 128(27): 5374-5385, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38917032

RESUMO

This study investigates the complex interaction between ozone and the autoxidation of 1-hexene over a wide temperature range (300-800 K), overlapping atmospheric and combustion regimes. It is found that atmospheric molecular mechanisms initiate the oxidation of 1-hexene from room temperature up to combustion temperatures, leading to the formation of highly oxygenated organic molecules. As temperature rises, the highly oxygenated organic molecules contribute to radical-branching decomposition pathways inducing a high reactivity in the low-temperature combustion region, i.e., from 550 K. Above 650 K, the thermal decomposition of ozone into oxygen atoms becomes the dominant process, and a remarkable enhancement of the conversion is observed due to their diradical nature, counteracting the significant negative temperature coefficient behavior usually observed for 1-hexene. In order to better characterize the formation of heavy oxygenated organic molecules at the lowest temperatures, two analytical performance methods have been combined for the first time: synchrotron-based mass-selected photoelectron spectroscopy and orbitrap chemical ionization mass spectrometry. At the lowest studied temperatures (below 400 K), this analytical work has demonstrated the formation of the ketohydroperoxides usually found during the LTC oxidation of 1-hexene, as well as of molecules containing up to nine O atoms.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38397626

RESUMO

Better understanding of the quality of life among nursing home residents with dementia is important for developing interventions. The objectives of this cross-sectional study were to examine factors associated with poor health-related quality of life in older people with dementia living in nursing homes in Hanoi, Vietnam. In-person interviews were conducted with 140 adults who were 60 years and older with dementia, and information about their quality of life was obtained using the Quality of Life in Alzheimer's Disease (QOL-AD) scale. The sociodemographic and clinical factors associated with poor health-related quality of life (lowest quartile) were assessed through the results of physical tests, interviews with nursing home staff, and review of medical records. The average age of the study sample was 78.3 years, 65% were women, and their average QOL-AD total score was 27.3 (SD = 4.4). Malnutrition, total dependence in activities of daily living, and urinary incontinence were associated with poor quality of life after controlling for multiple potentially confounding factors. Our findings show that Vietnamese nursing home residents with dementia have a moderate total quality of life score, and interventions based on comprehensive geriatric assessment remain needed to modify risk factors related to poor health-related quality of life.


Assuntos
Demência , Qualidade de Vida , Humanos , Feminino , Idoso , Masculino , Vietnã/epidemiologia , Atividades Cotidianas , Estudos Transversais , Casas de Saúde , Demência/epidemiologia
4.
Chem Commun (Camb) ; 58(94): 13139-13142, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36349724

RESUMO

Despite decades of research on alkene ozonolysis, the kinetic network of the archetypal case of ethylene (CH2CH2) with ozone (O3) still lacks consensus. In this work, experimental evidence of an elusive diradical pathway is provided through the detection of the 2-hydroperoxyacetaldehyde ketohydroperoxide and its decomposition product, glyoxal.


Assuntos
Glioxal , Ozônio , Cinética , Etilenos
5.
J Phys Chem A ; 126(34): 5784-5799, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35998573

RESUMO

Cyclohexane oxidation chemistry was investigated using a near-atmospheric pressure jet-stirred reactor at T = 570 K and equivalence ratio ϕ = 0.8. Numerous intermediates including hydroperoxides and highly oxygenated molecules were detected using synchrotron vacuum ultraviolet photoelectron photoion coincidence spectroscopy. Supported by high-level quantum calculations, the analysis of photoelectron spectra allowed the firm identification of molecular species formed during the oxidation of cyclohexane. Besides, this work validates recently published gas chromatography and synchrotron vacuum ultraviolet photoionization mass spectrometry data. Unambiguous detection of characteristic hydroperoxides (e.g., γ-ketohydroperoxides) and their respective decomposition products provides support for the conventional O2 addition channels up to the third addition and their relative contribution to the cyclohexane oxidation. The results were also compared with the predictions of a recently proposed new detailed kinetic model of cyclohexane oxidation. Most of the predictions are in line with the current experimental findings, highlighting the robustness of the kinetic model. However, the analysis of the recorded slow photoelectron spectra indicating the possible presence of C5 species in the kinetic model provides hints that the substituted cyclopentyl radicals from cyclohexyl ring opening might play a minor role in cyclohexane oxidation. Potentially important missing reactions are also discussed.

6.
Phys Chem Chem Phys ; 24(18): 10826-10837, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35485277

RESUMO

tert-Butyl hydroperoxide (tBuOOH) is a common intermediate in the oxidation of organic compounds that needs to be accurately quantified in complex gas mixtures for the development of chemical kinetic models of low temperature combustion. This work presents a combined theoretical and experimental investigation on the synchrotron-based VUV single photon ionization of gas-phase tBuOOH in the 9.0 - 11.0 eV energy range, including dissociative ionization processes. Computations consist of the determination of the structures, vibrational frequencies and the energetics of neutral and ionic tBuOOH. The Franck-Condon spectrum for the tBuOOH+ (X+) + e- ← tBuOOH (X) + hν transition is computed, where special treatment is undertaken because of the flexibility of tBuOOH, in particular regarding the OOH group. Through comparison of the experimental mass-selected threshold photoelectron spectra with explicitly correlated coupled cluster calculations and Franck-Condon simulations that account for the flexibility of the molecule, an estimation of the ionization energy is given. The appearance energy of the only fragment observed within the above-mentioned energy range, identified as the tert-butyl C4H9+, is also reported. Finally, the signal branching ratio between the parent and the fragment ions is provided as a function of photon energy, essential to quantify tBuOOH in gas-phase oxidation/combustion experiments via advanced mass spectrometry techniques.

7.
CNS Neurol Disord Drug Targets ; 21(7): 621-630, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34414874

RESUMO

AIMS: To investigate the efficacy and safety of Cerebrolysin and Cerebrolysin plus nootropics in the routine treatment of patients with acute ischemic stroke (AIS). BACKGROUND: Acute ischemic stroke (AIS) is a leading cause of disability with unmet treatment needs lacking effective drug therapy. Multimodal drugs modulating stroke pathophysiology as Cerebrolysin constitute a good therapeutic option. OBJECTIVE: In this study, we assessed the effects of Cerebrolysin and Cerebrolysin plus nootropics, in comparison with other nootropic drugs alone, on functional, neurological and cognitive recovery of patients with AIS in Vietnam. METHODS: This non-interventional, controlled, open-label, prospective and multicenter study included 398 AIS patients (234 males) treated with Cerebrolysin (n=190; 20 i.v. infusions of 10 ml), other nootropics (comparator group; n=86), or a combination of both (n=122). The study primary endpoint was the modified Ranking Scale (mRS) score on day 90. Secondary endpoints included study-period change in NIHSS score; percentage of well-recovered (mRS 0-2) patients, the proportion of good NIHSS response (≥6 points) cases, and MoCA scores at day 90; and safety indicators. RESULTS: Compared with other nootropics, both Cerebrolysin and combined therapy induced significant improvements (p<0.001) in: Functional recovery (mRS scores); percentage of well-recovered patients (Cerebrolysin: 81.6%; combination: 93.4%; comparator: 43.0%); neurological recovery (study- period NIHSS change); proportion of good NIHSS responders (Cerebrolysin: 77.5%; combination: 92.5%; comparator: 47.6%); and MoCA scores (Cerebrolysin: 23.3±4.8; combination: 23.7±4.1; comparator: 15.9±7.7). Compared to Cerebrolysin, combined therapy improved (p<0.01) mRS outcomes and NIHSS change, but not MoCA scores, in moderate-severe stroke (NIHSS>11) cases only. No drug-related adverse events were reported. CONCLUSION: Cerebrolysin alone or combined with other nootropics was effective and safe in routine AIS treatment, during both acute and recovery phases, which supports its use in daily clinical practice. Others: According to the results of this multicenter study, the importance of reducing differences in the treatment regimens of AIS in Vietnam should be further emphasized.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Fármacos Neuroprotetores , Nootrópicos , Acidente Vascular Cerebral , Aminoácidos , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Feminino , Humanos , Masculino , Fármacos Neuroprotetores/uso terapêutico , Nootrópicos/uso terapêutico , Gravidez , Estudos Prospectivos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Resultado do Tratamento , Vietnã
8.
Phys Chem Chem Phys ; 22(3): 1222-1241, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31850421

RESUMO

Through the use of tunable vacuum ultraviolet light generated by the DESIRS VUV synchrotron beamline, a jet-stirred reactor was coupled for the first time to an advanced photoionization mass spectrometer based upon a double imaging PhotoElectron PhotoIon COincidence (i2PEPICO) scheme. This new coupling was used to investigate the low-temperature oxidation of n-pentane, a prototype molecule for gasoline or diesel fuels. Experiments were performed under quasi-atmospheric pressure (1.1 bar) with a residence time of 3 s for two equivalence ratios (1/3 and 0.5) with a fuel initial mole fraction of 0.01. The measured time-of-flight mass spectra are in good agreement with those previously obtained with other photoionization mass spectrometers and, like those previous ones, display several m/z peaks for which the related species assignation is ambiguous. This paper shows how the analysis of the coincident mass-tagged Threshold PhotoElectron Spectra (TPES) together with first principle computations, consisting of the determination of the adiabatic ionization energies and the spectra of some products, may assist products' identification. The results mostly confirm those previously obtained by photoionization mass spectrometry and gas chromatography, but also allow a more accurate estimation of the 1-pentene/2-pentene mole fraction ratio. Our data also indicate a higher formation of acetone and methyl ethyl ketone than what is predicted by current models, as well as the presence of products that were not previously taken into account, such as methoxyacetylene, methyl vinyl ketone or furanone. The formation of three, four and five membered ring cyclic ethers is confirmed along with linear ketones: 2- and 3-pentanone. A significant general trend in indicating higher amounts of ketones than are indicated by gas chromatography is noted. Finally, TPES of alkenylhydroperoxides are also provided for the first time and constrains on the isomers identification are provided.

9.
Sci Rep ; 8(1): 3983, 2018 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-29507348

RESUMO

Idiopathic Pulmonary Fibrosis (IPF) is a progressive disorder that is marked by an over accumulation of activated fibroblast populations. Despite the improved understanding of many mechanisms within this disease, global gene expression analysis has few focused studies on the fibroblast, the central effector cell of progressive fibrosis. We present a unique analysis of IPF pulmonary fibroblasts as they transition through cell culture and identify in vitro altered cellular processes. Fibroblasts were isolated from diseased (n = 8) and non-diseased (n = 4) lungs. Global gene expression analysis was carried out at the initial point of isolation and after 3 weeks of culture. We identify several genes that are altered by removal of the fibroblast from the IPF environment. Comparison of this subset of genes to four previously published whole lung analyses refined our list to a small subset of key fibroblast specific genes important in IPF. Application of STRING database analysis and confirmation via in-vitro and histological assay highlights the CXCL14/CXCR4 chemokine axis with a possible role in the progression and/or activation of fibroblasts within the IPF lung. Our findings, present a possible therapeutic target for IPF and a model for the study and discovery of novel protein and processes in this terrible disease.


Assuntos
Quimiocinas CXC/genética , Fibroblastos/patologia , Fibrose Pulmonar Idiopática/genética , Receptores CXCR4/genética , Transcriptoma , Quimiocina CXCL12/análise , Quimiocina CXCL12/genética , Quimiocinas CXC/análise , Progressão da Doença , Feminino , Fibroblastos/metabolismo , Redes Reguladoras de Genes , Humanos , Fibrose Pulmonar Idiopática/patologia , Masculino , Receptores CXCR4/análise
10.
Combust Flame ; 161(3): 780-797, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24518851

RESUMO

This work is the third part of a study focusing on the combustion chemistry and flame structure of furan and selected alkylated derivatives, i.e. furan in Part I, 2-methylfuran (MF) in Part II, and 2,5-dimethylfuran (DMF) in the present work. Two premixed low-pressure (20 and 40 mbar) flat argon-diluted (50%) flames of DMF were studied with electron-ionization molecular-beam mass spectrometry (EI-MBMS) and gas chromatography (GC) under two equivalence ratios (φ=1.0 and 1.7). Mole fractions of reactants, products, and stable and radical intermediates were measured as a function of the distance to the burner. Kinetic modeling was performed using a reaction mechanism that was further developed in the present series, including Part I and Part II. A reasonable agreement between the present experimental results and the simulation is observed. The main reaction pathways of DMF consumption were derived from a reaction flow analysis. Also, a comparison of the key features for the three flames is presented, as well as a comparison between these flames of furanic compounds and those of other fuels. An a priori surprising ability of DMF to form soot precursors (e.g. 1,3-cyclopentadiene or benzene) compared to less substituted furans and to other fuels has been experimentally observed and is well explained in the model.

11.
Combust Flame ; 161(3): 766-779, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24518895

RESUMO

This is Part II of a series of three papers which jointly address the combustion chemistry of furan and its alkylated derivatives 2-methylfuran (MF) and 2,5-dimethylfuran (DMF) under premixed low-pressure flame conditions. Some of them are considered to be promising biofuels. With furan as a common basis studied in Part I of this series, the present paper addresses two laminar premixed low-pressure (20 and 40 mbar) flat argon-diluted (50%) flames of MF which were studied with electron-ionization molecular-beam mass spectrometry (EI-MBMS) and gas chromatography (GC) for equivalence ratios φ=1.0 and 1.7, identical conditions to those for the previously reported furan flames. Mole fractions of reactants, products as well as stable and reactive intermediates were measured as a function of the distance above the burner. Kinetic modeling was performed using a comprehensive reaction mechanism for all three fuels given in Part I and described in the three parts of this series. A comparison of the experimental results and the simulation shows reasonable agreement, as also seen for the furan flames in Part I before. This set of experiments is thus considered to be a valuable additional basis for the validation of the model. The main reaction pathways of MF consumption have been derived from reaction flow analyses, and differences to furan combustion chemistry under the same conditions are discussed.

12.
Combust Flame ; 161(3): 748-765, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24518999

RESUMO

Fuels of the furan family, i.e. furan itself, 2-methylfuran (MF), and 2,5-dimethylfuran (DMF) are being proposed as alternatives to hydrocarbon fuels and are potentially accessible from cellulosic biomass. While some experiments and modeling results are becoming available for each of these fuels, a comprehensive experimental and modeling analysis of the three fuels under the same conditions, simulated using the same chemical reaction model, has - to the best of our knowledge - not been attempted before. The present series of three papers, detailing the results obtained in flat flames for each of the three fuels separately, reports experimental data and explores their combustion chemistry using kinetic modeling. The first part of this series focuses on the chemistry of low-pressure furan flames. Two laminar premixed low-pressure (20 and 40 mbar) flat argon-diluted (50%) flames of furan were studied at two equivalence ratios (φ=1.0 and 1.7) using an analytical combination of high-resolution electron-ionization molecular-beam mass spectrometry (EI-MBMS) in Bielefeld and gas chromatography (GC) in Nancy. The time-of-flight MBMS with its high mass resolution enables the detection of both stable and reactive species, while the gas chromatograph permits the separation of isomers. Mole fractions of reactants, products, and stable and radical intermediates were measured as a function of the distance to the burner. A single kinetic model was used to predict the flame structure of the three fuels: furan (in this paper), 2-methylfuran (in Part II), and 2,5-dimethylfuran (in Part III). A refined sub-mechanism for furan combustion, based on the work of Tian et al. [Combustion and Flame 158 (2011) 756-773] was developed which was then compared to the present experimental results. Overall, the agreement is encouraging. The main reaction pathways involved in furan combustion were delineated computing the rates of formation and consumption of all species. It is seen that the predominant furan consumption pathway is initiated by H-addition on the carbon atom neighboring the O-atom with acetylene as one of the dominant products.

13.
Energy Fuels ; 27(4): 2226-2245, 2013 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-23712124

RESUMO

To better understand the chemistry of the combustion of ethanol, the structure of five low pressure laminar premixed flames has been investigated: a pure methane flame (φ=1), three pure ethanol flames (φ=0.7, 1.0, and 1.3), and an ethanol/methane mixture flames (φ=1). The flames have been stabilized on a burner at a pressure of 6.7 kPa using argon as dilutant, with a gas velocity at the burner of 64.3 cm/s at 333 K. The results consist of mole fraction profiles of 20 species measured as a function of the height above the burner by probe sampling followed by online gas chromatography analyses. A mechanism for the oxidation of ethanol was proposed. The reactions of ethanol and acetaldehyde were updated and include recent theoretical calculations while that of ethenol, dimethyl ether, acetone, and propanal were added in the mechanism. This mechanism was also tested against experimental results available in the literature for laminar burning velocities and laminar premixed flame where ethenol was detected. The main reaction pathways of consumption of ethanol are analyzed. The effect of the branching ratios of reaction C2H5OH+OH→Products+H2O is also discussed.

14.
PLoS One ; 7(7): e41013, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22911730

RESUMO

UNLABELLED: X-linked adrenoleukodystrophy (X-ALD) is caused by mutations in the ABCD1 gene and is characterized by impaired beta-oxidation of very-long-chain fatty acids (VLCFA) and subsequent VLCFA accumulation in tissues. In adulthood X-ALD most commonly manifests as a gradually progressive myelopathy, (adrenomyeloneuropathy; AMN) without any curative or disease modifying treatments. We recently showed that bezafibrate (BF), a drug used for the treatment of hyperlipidaemia, reduces VLCFA accumulation in X-ALD fibroblasts by inhibiting ELOVL1, an enzyme involved in the VLCFA synthesis. We therefore designed a proof-of-principal clinical trial to determine whether BF reduces VLCFA levels in plasma and lymphocytes of X-ALD patients. Ten males with AMN were treated with BF for 12 weeks at a dose of 400 mg daily, followed by 12 weeks of 800 mg daily. Every 4 weeks patients were evaluated for side effects and blood samples were taken for analysis. Adherence was good as indicated by a clear reduction in triglycerides. There was no reduction in VLCFA in either plasma or lymphocytes. Plasma levels of BF did not exceed 25 µmol/L. We concluded that BF, at least in the dose given, is unable to lower VLCFA levels in plasma or lymphocytes in X-ALD patients. It is unclear whether this is due to the low levels of BF reached in plasma. Our future work is aimed at the identification of highly-specific inhibitors of ELOVL1 that act at much lower concentrations than BF and are well tolerated. BF appears to have no therapeutic utility in X-ALD. TRIAL REGISTRATION: ClinicalTrials.gov NCT01165060.


Assuntos
Adrenoleucodistrofia/tratamento farmacológico , Bezafibrato/uso terapêutico , Hipolipemiantes/uso terapêutico , Adrenoleucodistrofia/metabolismo , Bezafibrato/administração & dosagem , Bezafibrato/farmacologia , Humanos , Hipolipemiantes/administração & dosagem , Hipolipemiantes/farmacologia , Masculino , Resultado do Tratamento
15.
Mol Cell Biol ; 32(17): 3392-402, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22733991

RESUMO

Controlled renewal of the epithelium with precise cell distribution and gene expression patterns is essential for colonic function. GATA6 is expressed in the colonic epithelium, but its function in the colon is currently unknown. To define GATA6 function in the colon, we conditionally deleted Gata6 throughout the epithelium of small and large intestines of adult mice. In the colon, Gata6 deletion resulted in shorter, wider crypts, a decrease in proliferation, and a delayed crypt-to-surface epithelial migration rate. Staining techniques and electron microscopy indicated deficient maturation of goblet cells, and coimmunofluorescence demonstrated alterations in specific hormones produced by the endocrine L cells and serotonin-producing cells. Specific colonocyte genes were significantly downregulated. In LS174T, the colonic adenocarcinoma cell line, Gata6 knockdown resulted in a significant downregulation of a similar subset of goblet cell and colonocyte genes, and GATA6 was found to occupy active loci in enhancers and promoters of some of these genes, suggesting that they are direct targets of GATA6. These data demonstrate that GATA6 is necessary for proliferation, migration, lineage maturation, and gene expression in the mature colonic epithelium.


Assuntos
Colo/citologia , Colo/metabolismo , Fator de Transcrição GATA6/genética , Fator de Transcrição GATA6/metabolismo , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Animais , Diferenciação Celular , Linhagem Celular , Colo/ultraestrutura , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Feminino , Deleção de Genes , Regulação da Expressão Gênica , Células Caliciformes/citologia , Células Caliciformes/metabolismo , Mucosa Intestinal/ultraestrutura , Masculino , Camundongos
16.
Energy (Oxf) ; 43(1): 4-18, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23700355

RESUMO

Due to growing environmental concerns and diminishing petroleum reserves, a wide range of oxygenated species has been proposed as possible substitutes to fossil fuels: alcohols, methyl esters, acyclic and cyclic ethers. After a short review the major detailed kinetic models already proposed in the literature for the combustion of these molecules, the specific classes of reactions considered for modeling the oxidation of acyclic and cyclic oxygenated molecules respectively, are detailed.

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