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1.
Artigo em Inglês | MEDLINE | ID: mdl-32866305

RESUMO

Chemical bonds are traditionally assigned as electron-sharing or donor-acceptor/dative. External criteria such as the nature of the dissociation process, energy partitioning schemes or quantum chemical topology are invoked to assess the bonding situation. However, for systems with marked multi-reference character, this binary categorization might not be precise enough to render the bonding properties. A third scenario can be foreseen: spin polarized bonds . To illustrate this, we present the case of NaBH 3 - cluster. According to our analysis, NaBH 3 - exhibits a strong diradical character and cannot be classified as electron-sharing or dative bond . We elaborate on the common problems of popular bonding description. Additionally, we provide a simple model, based on the bond order and local spin indicators, which discriminates between all three bonding situations.

2.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32888675

RESUMO

OBJECTIVES: To evaluate the success rate of primary stapedotomy and to investigate the influence of prosthesis diameter on hearing outcome. MATERIAL AND METHODS: Retrospective medical chart review of 125 cases who underwent primary small fenestra stapedotomy, from January 2001 to December 2018. The study population was divided in two groups based on Teflon prosthesis diameter - .6mm (60%, N=75) and .4mm (40%, N=50). Pre- and postoperative (≥12 months) air-conduction (AC), bone conduction (BC) and air-bone gap (ABG) thresholds were compared. RESULTS: Postoperative ABG≤10dB and ≤20dB was achieved by 65.7% and 90% of the patients. A functional hearing (PTA-AC≤30dB) was achieved by 59.2% of patients. Sensorineural hearing loss (SNHL, worsening in BC-PTA>10dB) was identified in 7.2% of patients. Comparison of the .6mm- and .4mm-groups, revealed no differences regarding improvements in AC-PTA (22.4 vs. 20.7dB, p=.56), BC-PTA (3.4 vs. 2.3dB, p=.54) and ABG-PTA (19.1 vs. 18.4dB, p=.77). Hearing outcome evaluation identified similar postoperative success rate (.6mm, 79.7% vs. .4mm, 62%, p=.336) and comparable functional hearing (.6mm, 64% vs. .4mm, 52%; p=.197). The incidence of postoperative SNHL was similar between the two pistons (.6m, 5.3% vs. .4mm, 10%, p=.481). CONCLUSION: Primary small fenestra stapedotomy is an effective and safe procedure. A postoperative ABG within 10dB was achieved in 67.2% of patients and there was a reduced incidence of sensorineural hearing loss. Hearing outcome was not influenced by diameter of the selected prosthesis. Postoperative bone conduction hearing thresholds did not differ between the groups, which revealed no significant inner ear trauma caused by the larger piston. Although we did not find evidence to suggest one piston over the other, our results showed a trend toward better results with the larger prosthesis.

3.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32862972

RESUMO

OBJECTIVES: To evaluate success rate of type I tympanoplasty in adults and to investigate the importance of selected prognostic factors on graft uptake. MATERIAL AND METHODS: Retrospective medical chart review of 155 patients who underwent Type I Tympanoplasty, in our department, from January 2013 to December 2017. Graft uptake rate was evaluated and the effects of prognostic factors on surgical outcome such as sex, smoking and otological surgery history, status of the contralateral ear, size and location of the perforation, middle ear mucosa status, surgical approach and graft material. Preoperative and postoperative audiometric data were collected, and the functional success was determined. RESULTS: The overall surgical anatomical success rate was 75%. Analysis of the selected variables, identified as independent prognostic factors of anatomical unsuccess (95% CI): smoking (OR=3.29, p<.01), middle ear tympanosclerosis (OR=2.96; p=.04). Perforations above 50% of the tympanic membrane area had a borderline effect on graft uptake (p=.05). There was a significative improvement in the average air conduction thresholds of 7.44dB and an ABG closure rate at 10dB and 20dB was achieved in 47% and 84.5%, respectively. Patients who received temporalis fascia graft had similar hearing gain compared to patients who underwent cartilage tympanoplasty (7.7 vs. 7.3dB, p=.79). CONCLUSION: Type I tympanoplasty is an effective and safe procedure with a high anatomical success rate in the treatment of mucosal COM. Poorer outcomes were found in patients with smoking habits, in those with tympanosclerosis of middle ear mucosa and in larger perforations. These prognostic factors should be considered in surgical planning and patients should be advised to quit smoking. Tympanoplasty with cartilage graft had a hearing outcome comparable to temporalis fascia graft and should be considered in high-risk patients.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32696403

RESUMO

The occurrence of local high-pollution episodes in densely populated urban areas, which have huge fleets of vehicles, is currently one of the most worrying problems associated with air pollution worldwide. Such episodes are produced under specific meteorological conditions, which favour the sudden increase of levels of air pollutants. This study has investigated the influence of the mixing layer height (MLH) on the concentration levels of atmospheric pollutants and daily mortality in Madrid, Spain, during the period 2011-2014. It may help to understand the causes and impact of local high-pollution episodes. MLH at midday over Madrid was daily estimated from meteorological radio soundings. Then, days with different MLH over this urban area were characterized by meteorological parameters registered at different levels of an instrumented tower and by composite sea level pressure maps, representing the associated synoptic meteorological scenarios. Next, statistically significant associations between MLH and levels of PM10, PM2.5, NO, NO2, CO and ultra-fine particles number concentrations registered at representative monitoring stations were evaluated. Finally, associations between all-natural cause daily mortality in Madrid, MLH, and air pollutants were estimated using conditional Poisson regression models. The reduction of MLH to values below 482 m above-ground level under strong atmospheric stagnation conditions was accompanied by a statistically significant increase in levels of NO, NO2, CO, PM2.5 and ultra-fine particle number concentrations at urban-traffic and suburban monitoring sites. The decrease of the MLH was also associated to a linear increase of the daily number of exceedances of the UE NO2 hourly limit value (200 µg/m3) and levels of air pollutants at hotspot urban-traffic monitoring stations. Also, a statistically significant association of the MLH with all-natural cause daily mortality was obtained. When the MLH increased by 830 m, the risk of mortality decreased by 2.5% the same day and by 3.3% the next day, when African dust episodic days were excluded. They were also higher in absolute terms than the increases in risk of mortality that were determined for the exposition to any other air pollutant. Our results suggest that when the prediction models foresee values of MLH below 482 m above-ground level in Madrid, the evolution of high-contamination episodes will be very favourable. Therefore, short-term policy measures will have to be implemented to reduce NO, NO2, CO, PM2.5 and ultra-fine particle emissions from anthropogenic sources in this southern European urban location.

5.
Braz J Infect Dis ; 24(4): 343-348, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32721387

RESUMO

OBJECTIVES: Differential diagnosis of COVID-19 includes a broad range of conditions. Prioritizing containment efforts, protective personal equipment and testing can be challenging. Our aim was to develop a tool to identify patients with higher probability of COVID-19 diagnosis at admission. METHODS: This cross-sectional study analyzed data from 100 patients admitted with suspected COVID-19. Predictive models of COVID-19 diagnosis were performed based on radiology, clinical and laboratory findings; bootstrapping was performed in order to account for overfitting. RESULTS: A total of 29% of patients tested positive for SARS-CoV-2. Variables associated with COVID-19 diagnosis in multivariate analysis were leukocyte count ≤7.7×103mm-3, LDH >273U/L, and chest radiographic abnormality. A predictive score was built for COVID-19 diagnosis, with an area under ROC curve of 0.847 (95% CI 0.77-0.92), 96% sensitivity and 73.5% specificity. After bootstrapping, the corrected AUC for this model was 0.827 (95% CI 0.75-0.90). CONCLUSIONS: Considering unavailability of RT-PCR at some centers, as well as its questionable early sensitivity, other tools might be used in order to identify patients who should be prioritized for testing, re-testing and admission to isolated wards. We propose a predictive score that can be easily applied in clinical practice. This score is yet to be validated in larger populations.


Assuntos
Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Adulto , Idoso , Betacoronavirus , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Valor Preditivo dos Testes , Radiografia Torácica , Sensibilidade e Especificidade
6.
Acta otorrinolaringol. esp ; 71(3): 160-165, mayo-jun. 2020. graf, tab
Artigo em Inglês | IBECS | ID: ibc-192631

RESUMO

OBJECTIVE: Epistaxis is one of the commonest causes of attendance of Otolaryngology emergency rooms. Given its incidence, potential severity and high recurrence rate, a systematic and careful management is mandatory. This work aims to define prognostic factors of epistaxis recurrence. MATERIAL AND METHODS: Retrospective review of medical records of patients with epistaxis admitted to our emergency department from January 2012 to December 2016. Data of 1005 patients with idiopathic epistaxis were analysed and independent risk factors for recurrence were determined by multiple logistic regression analysis. RESULTS: Recurrence of epistaxis was found in 303 (30.1%) patients. Patients with recurrent epistaxis were older (p < .001) and more commonly had a history of hypertension (p = .001) and antiplatelet (p = .048) and anticoagulant (p = .001) use than those with episodic epistaxis. Age (adjusted OR 1.21, 95%CI 1.08-1.32, p = .003) and anticoagulant use (adjusted OR 2.68, 95%CI 1.94-3.70, p = .009) were predictors of increased risk of recurrent epistaxis. Gender, alcohol abuse, medical history, active bleeding at admission, unidentified bleeding point or treatment modalities were not associated with recurrence. CONCLUSIÓN: Age and use of anticoagulation drugs were risk factors for recurrence of epistaxis. None of the previously described risk factors for episodic epistaxis were found to increase the risk of recurrence. Knowledge of factors involved in recurrence might provide important information for assessment and management of increased risk patients


OBJETIVO: La epistaxis es una causa frecuente de asistencia a los servicios de urgencias de otorrinolaringología. Dada su incidencia, posible gravedad y alta tasa de recurrencia, es obligatorio un manejo sistemático y cuidadoso. Este trabajo tiene como objetivo definir los factores pronósticos de recurrencia de la epistaxis. MATERIAL Y MÉTODOS: Revisión retrospectiva de los registros médicos de pacientes con epistaxis admitidos en nuestro servicio de urgencias desde enero de 2012 a diciembre de 2016. Se analizaron los datos de 1.005 pacientes con epistaxis idiopática, y se determinaron los factores de riesgo independientes de recurrencia mediante análisis de regresión logística múltiple. RESULTADOS: La recurrencia de la epistaxis se encontró en 303 (30,1%) pacientes. Los pacientes con epistaxis recurrente eran mayores (p < 0,001), tenían con más frecuencia antecedentes de hipertensión (p = 0,001) y de tratamiento con antiplaquetarios (p = 0,048) y anticoagulantes (p = 0,001) que aquellos con epistaxis episódica. La edad (OR ajustada: 1,21; IC 95%: 1,08-1,32; p = 0,003) y el uso de anticoagulantes (OR ajustada: 2,68; IC 95%: 1,94-3,7; p = 0,009) fueron factores predictivos de mayor riesgo de epistaxis recurrente. El sexo, el abuso del alcohol, el historial médico, el sangrado activo al ingreso, el punto de sangrado no identificado o las modalidades de tratamiento, no se asociaron a la recurrencia. CONCLUSIÓN: La edad y el uso de medicamentos anticoagulantes fueron factores de riesgo para la recurrencia de la epistaxis. Ninguno de los factores de riesgo descritos anteriormente para la epistaxis episódica aumentó el riesgo de recurrencia. El conocimiento de los factores involucrados en la recurrencia podría proporcionar información importante para la evaluación y el manejo de los pacientes de mayor riesgo


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Epistaxe/epidemiologia , Recidiva , Prognóstico , Inibidores da Agregação de Plaquetas/uso terapêutico , Estudos Retrospectivos , Epistaxe/tratamento farmacológico , Ficha Clínica , Fatores de Risco , Modelos Logísticos , Fatores Etários , Epistaxe/etiologia
7.
Tree Physiol ; 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483620

RESUMO

Plant hydraulics is key for plant survival and growth because it is linked to gas-exchange and drought resistance. Although the environment influences plant hydraulics, there is no clear consensus on the effect of nitrogen (N) supply, which may be, in part, due to different hydraulic conductance normalization criteria and studied species. The objective of this study was to compare the variation of root hydraulic properties using several normalization criteria in four pine species in response to three contrasting N fertilization regimes. We studied four closely related, yet ecologically distinct species: Pinus nigra J.F. Arnold, Pinus pinaster Ait., and Pinus pinea L. and Pinus halepensis Mill. Root hydraulic conductance (Kh) was measured with a high-pressure flow meter and values were normalized by total leaf area (leaf specific conductance, Kl), xylem cross-section area (xylem specific conductance, Ks), total root area (root specific conductance, Kr) and the area of fine roots (fine root specific conductance, Kfr). Controlling for organ size differences allowed comparing the hydraulic efficiency of roots to supply or absorb water among fertilization treatments and species. The effect of N on the root hydraulic efficiency depended on the normalization criteria. Increasing N availability reduced Kl and Ks, but increased Kh, Kr and especially Kfr. The positive effect of N on Kr and Kfr was positively related to seedling relative growth rate and was also consistent with published results at the interspecific level, whereby plant hydraulics is positively linked to photosynthesis and transpiration rate and fast growth. In contrast, normalization by leaf area and xylem cross-section area (Kl and Ks) reflected opposite responses to Kr and Kfr. This indicates that the normalization criteria determine the interpretation of the effect of N on plant hydraulics, which can limit species and treatment comparisons.

8.
J Steroid Biochem Mol Biol ; 202: 105720, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32565249

RESUMO

The synonymous single nucleotide polymorphism (SNP) rs731236, located in the vitamin D receptor (VDR) gene (Taq I) has been associated with both decreased levels of the protein in peripheral blood mononuclear cells and a fibrosis-related complication in Crohn´s disease (CD). Interactions between VDR and a protein-disulfide isomerase-associated 3 (PDIA3) in the regulation of extracellular matrix have been reported and we aim to analyze the relevance of the VDR genotypes and the effects of Vitamin D (VD) in the expression of VDR, PDIA3 and proliferation of intestinal fibroblasts. Human intestinal fibroblasts were isolated from the non-affected surgical resections of colorectal patients and classified according to the VDR genotype. In some cases, cells were transfected with specific PDIA3 siRNA. Basal and VD-stimulated expression of VDR, PDIA3 and Collagen 1A1 (COL1A1) as well as fibroblast migration/proliferation were analyzed. Our data show that intestinal fibroblasts homozygous for the C allele in the VDR gene exhibited lower VDR protein levels and higher proliferation than cells homozygous for the T allele. VD increased VDR and attenuated the accelerated proliferation of CC fibroblasts. The diminished VDR level detected in CC cells was associated with increased levels of both PDIA3 and COL1A1 expression and the transient silencing of PDIA3 significantly reduced COL1A1 expression. We conclude that intestinal fibroblasts homozygous for the C allele in the VDR gene exhibited: reduced VDR protein levels, increased proliferation and increased PDIA3/COL1A1 expression. Treatment with VD increased VDR and attenuated proliferation of these cells.

9.
Phys Chem Chem Phys ; 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32441724

RESUMO

The calculation of nonlinear optical properties (NLOPs) using density functional theory (DFT) remains a challenge in computational chemistry. Although the existing range-separated functionals display the best performance for the calculation of this type of properties, their errors strongly depend on the family of molecules studied. Herein, we have explored a new strategy to empirically tune the range-separated LC-BLYP method to improve the accuracy of the calculation of the second hyperpolarizabilities (γ), which are poorly described by current density functional approximations. First, we benchmarked nine of the most accurate commonly used range-separated hybrid and optimally tuned functionals (i.e. B3LYP, PBE0, BH&HLYP, M06-2X, MN15, ωB97X-D, CAM-B3LYP, LC-BLYP and OT-LC-BLYP) for the calculation of γ using as a reference the CCSD(T) values of a chemically diverse set of 60 molecules. Among these nine functionals, LC-BLYP gives the lowest average errors. We determined the value of the range-separation parameter ω required to reproduce the CCSD(T) second hyperpolarizabilities with the LC-BLYP functional (ωCC) for the set of 60 molecules. Our new tuned range-separated functional, Tα-LC-BLYP, uses a quadratic correlation between ωCC and a molecular descriptor in terms of the linear polarizability and the number of electrons in the molecule. The average error of the γ values obtained with Tα-LC-BLYP is reduced by half or more as compared with the most accurate among the nine density functional approximations benchmarked.

10.
Nutrients ; 12(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32244667

RESUMO

Vitamin D (VD) deficiency has been associated to Crohn's disease (CD) pathogenesis, and the exogenous administration of VD improves the course of the disease, but the mechanistic basis of these observations remains unknown. Vitamin D receptor (VDR) mediates most of the biological functions of this hormone, and we aim to analyze here the expression of VDR in intestinal tissue, epithelial cells, and fibroblasts from CD patients. The effects of VD on a fibroblast wound healing assay and murine intestinal fibrosis are also analyzed. Our data show diminished VDR protein levels in surgical resections and epithelial cells from CD patients. In intestinal fibroblasts isolated from damaged tissue of CD patients, we detected enhanced migration and decreased VDR expression compared with both fibroblasts from non-damaged tissue of the same CD patient or control fibroblasts. Treatment with VD increased VDR protein levels, avoided the accelerated migration in CD fibroblasts, and prevented murine intestinal fibrosis induced by the heterotopic transplant model. In conclusion, our study demonstrates diminished VDR protein levels associated with enhanced migration in intestinal fibroblasts from damaged tissue of CD patients. In these cells, VD accumulates VDR and normalizes migration, which supports that CD patients would benefit from the VD anti-fibrotic therapeutic value that we demonstrate in a murine experimental model.

11.
Artigo em Inglês | MEDLINE | ID: mdl-32339395

RESUMO

Nitrosyl-metal bonding relies on the two interactions between the pair of N-O-π* and two of the metal's d orbitals. These (back)bonds are largely covalent, which makes their allocation in the course of an oxidation-state determination ambiguous. However, apart from M-N-O-angle or net-charge considerations, IUPAC's "ionic approximation" is a useful tool to reliably classify nitrosyl metal complexes in an orbital-centered approach.

12.
Acta otorrinolaringol. esp ; 71(1): 16-25, ene.-feb. 2020. tab, graf
Artigo em Inglês | IBECS | ID: ibc-192431

RESUMO

OBJECTIVES: Unilateral sinonasal disease is commonly encountered in practice and represents an issue of major concern since neoplasms may mimic inflammatory conditions. This paper aims to describe the demographic, clinical and radiological patterns of unilateral pathologies and, accordingly, to establish a guiding algorithm for diagnosis and management. MATERIAL AND METHODS: We conducted a retrospective review of medical records of patients with unilateral sinus opacification on CT scan who underwent endoscopic nasal surgery in our department from January 2011 to December 2017. RESULTS: Of the 150 patients included, 97(64.7%) and 53(35.3%) had inflammatory and neoplastic pathology, respectively. In the neoplastic group, malignancy was present in 35% of patients. Neoplastic conditions were more common in males (p = 0.02) and older patients (56 ± 18 years vs. 38 ± 18, p < .01). Nasal mass or polyp was observed in 56.7% patients. Chronic sinusitis was the most prevalent inflammatory condition, whereas inverted papilloma and osteoma were the most frequent neoplasms. Facial neuralgia, paraesthesia, epistaxis and, on CT scan, superior Lund-Mackay scores, bone remodelling and erosion were significantly more common in neoplastic conditions. Excellent agreement between punch biopsy and postoperative histological results was obtained (k = .883, p < .001). CONCLUSION: A sequential and careful management of unilateral lesions is mandatory. Based on our experience, we propose that, as routine, physical examination should be complemented with nasal endoscopy, CT scan and punch biopsy, in case of visible mass. Although clinical and radiological information might raise suspicion of some conditions, final diagnosis can only be established with histological examination of the surgical specimen


OBJETIVOS: La patología nasal unilateral es común en la práctica clínica y causa preocupación ya que las neoplasias pueden mimetizar las condiciones inflamatorias. Este trabajo pretende describir los patrones demográficos, clínicos y radiológicos de las patologías unilaterales y establecer un algoritmo para el diagnóstico y manejo. MATERIAL Y MÉTODOS: Revisión retrospectiva de los registros médicos de pacientes con opacificación sinusal unilateral en la TC sometidos a cirugía nasal endoscópica en nuestro servicio desde enero de 2011 hasta diciembre de 2017. RESULTADOS: De los 150 pacientes incluidos, 97(64,7%) y 53(35,3%) presentaban patología inflamatoria y neoplásica, respectivamente. En el grupo neoplásico, la malignidad estaba presente en el 35% de los pacientes. Las condiciones neoplásicas fueron más comunes en hombres (p = 0,02) y pacientes mayores (56 ± 18 años vs. 38 ± 18, p < 0,01). Se observó masa nasal en el 56,7% de los pacientes. La sinusitis crónica fue la afección inflamatoria más prevalente, mientras que el papiloma invertido y el osteoma fueron las neoplasias más frecuentes. La neuralgia facial, la parestesia, la epistaxis y, en la TC, las puntuaciones superiores de Lund-Mackay, remodelación y erosión ósea fueron significativamente más comunes en los trastornos neoplásicos. Se encontró una excelente concordancia entre la biopsia por punción y los resultados histológicos postoperatorios (k = 0,88, p < 0,01). CONCLUSIÓN: Con base en nuestra experiencia, proponemos que, el examen físico se complemente con endoscopia nasal, TC y biopsia, en caso de una masa visible. A pesar de que la información clínica y radiológica puede generar sospechas de algunas afecciones, el diagnóstico final solo se puede establecer con el examen histológico postoperatorio


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Doenças dos Seios Paranasais/diagnóstico por imagem , Algoritmos , Tomografia Computadorizada por Raios X , Estudos Retrospectivos , Registros Médicos/estatística & dados numéricos , Endoscopia , Doenças dos Seios Paranasais/patologia , Sinusite/epidemiologia , Neuralgia Facial/epidemiologia , Doença Crônica , Pólipos Nasais/complicações , Fatores de Risco
13.
Chemosphere ; 248: 125896, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32006840

RESUMO

Biomass burning is a major air pollution problem all around the world. However, the identification and quantification of its contribution to ambient aerosol levels is a difficult task due to the generalized lack of observations of molecular markers. This paper presents the results of a yearlong study of organic constituents of the atmospheric aerosol at a rural site in southern Spain (Villanueva del Arzobispo, Jaén). Sampling was performed for PM10 and PM2.5, and a total of 116 and 115 samples, respectively, were collected and analyzed by GC/MS, quantifying 77 organic compounds. Higher levels of organic pollutants were recorded from November to March, coinciding with the cold season when domestic combustion is a common practice in rural areas. This jointly with adverse meteorological conditions, e.g. strong atmospheric stability, produced severe pollution episodes with high PMx ambient levels. High daily concentrations of tracers were reached, up to 26 ng m-3 for B(a)P and 6065 ng m-3 for levoglucosan in PM2.5, supporting that biomass burning is a major source of pollution at rural areas. A multivariate statistical study based on factor and cluster analysis, was applied to the data set with the aim to distinguish sources of organic compounds. The main resulting sources were related with biomass combustion, secondary organic aerosol (SOA), biogenic emissions, lubricating oil and soil organic components. A preliminary organic source profile for olive wastes burning was evaluated, based on cluster results, showing anhydrosacharides and xylitol are the main emitted compounds, accounting for more than 85% of the quantified compounds. Other source compounds were fatty acids, diacids, aliphatics, sugars, sugar alcohols, PAHs and quinones.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Incineração , Olea , Poluição do Ar/análise , Biomassa , Monitoramento Ambiental , Compostos Orgânicos/análise , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Estações do Ano , Solo , Espanha
14.
Molecules ; 25(1)2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31935971

RESUMO

The use of centroids of localized orbitals as a method to derive oxidation states (OS) from first-principles is critically analyzed. We explore the performance of the closest-atom distance criterion to assign electrons for a number of challenging systems, including high-valent transition metal compounds, π-adducts, and transition metal (TM) carbenes. Here, we also introduce a mixed approach that combines the position of the centroids with Bader's atomic basins as an alternative criterion for electron assignment. The closest-atom criterion performs reasonably well for the challenging systems, but wrongly considers O-H and N-H bonds as hydrides. The new criterion fixes this problem, but underperforms in the case of TM carbenes. Moreover, the OS assignment in dubious cases exhibit undesirable dependence on the particular choice for orbital localization.


Assuntos
Modelos Teóricos , Oxirredução , Metano/análogos & derivados , Metano/química , Modelos Moleculares , Prótons , Teoria Quântica
15.
J Crohns Colitis ; 14(2): 230-239, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31359032

RESUMO

BACKGROUND AND AIMS: Epithelial-mesenchymal transition [EMT] has been related to fibrosis and fistula formation, common complications associated with Crohn´s disease [CD]. The WNT signalling pathway mediates EMT, and specific WNT/FZD interactions have been related to the activation of this process in several diseases. We aim to analyse the relevance of EMT and WNT ligands and receptors in the penetrating behaviour of CD. METHODS: Intestinal surgical resections were obtained from control and CD patients with a stenotic or penetrating behaviour. Fibrosis was determined by the histological analysis of collagen deposition and EMT by confocal microscopy. The expression of WNT ligands, inhibitors, and FZD receptors was analysed by RT-PCR, WB, IH, and IF studies. The effects of WNT2b and the role of FZD4 in EMT were analysed in HT29 epithelial cells. RESULTS: Fibrosis and expression of EMT markers were detected in samples from CD patients irrespective of the clinical behaviour. However, an increased colocalisation of E-CADHERIN and VIMENTIN, an increased number of cells expressing WNT2b, and a higher expression of FZD4 and WNT2b/FZD4 interaction, were detected in intestinal tissue from the penetrating compared with the stenotic CD behaviour. WNT2b induced EMT in HT29 cells through FZD4 activation. CONCLUSIONS: An increased EMT, associated with increased WNT2b/FZD4 interaction, was detected in intestinal tissue from CD patients with a penetrating behaviour. WNT2b, through FZD4 activation, induces EMT in vitro which points to a novel pharmacological target to prevent intestinal penetrating complications of CD.

16.
Acta Otorrinolaringol Esp ; 71(1): 16-25, 2020.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31349894

RESUMO

OBJECTIVES: Unilateral sinonasal disease is commonly encountered in practice and represents an issue of major concern since neoplasms may mimic inflammatory conditions. This paper aims to describe the demographic, clinical and radiological patterns of unilateral pathologies and, accordingly, to establish a guiding algorithm for diagnosis and management. MATERIAL AND METHODS: We conducted a retrospective review of medical records of patients with unilateral sinus opacification on CT scan who underwent endoscopic nasal surgery in our department from January 2011 to December 2017. RESULTS: Of the 150 patients included, 97(64.7%) and 53(35.3%) had inflammatory and neoplastic pathology, respectively. In the neoplastic group, malignancy was present in 35% of patients. Neoplastic conditions were more common in males (p=0.02) and older patients (56±18 years vs. 38±18, p<.01). Nasal mass or polyp was observed in 56.7% patients. Chronic sinusitis was the most prevalent inflammatory condition, whereas inverted papilloma and osteoma were the most frequent neoplasms. Facial neuralgia, paraesthesia, epistaxis and, on CT scan, superior Lund-Mackay scores, bone remodelling and erosion were significantly more common in neoplastic conditions. Excellent agreement between punch biopsy and postoperative histological results was obtained (k=.883, p<.001). CONCLUSION: A sequential and careful management of unilateral lesions is mandatory. Based on our experience, we propose that, as routine, physical examination should be complemented with nasal endoscopy, CT scan and punch biopsy, in case of visible mass. Although clinical and radiological information might raise suspicion of some conditions, final diagnosis can only be established with histological examination of the surgical specimen.

17.
Acta Otorrinolaringol Esp ; 71(3): 160-165, 2020.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31521240

RESUMO

OBJECTIVE: Epistaxis is one of the commonest causes of attendance of Otolaryngology emergency rooms. Given its incidence, potential severity and high recurrence rate, a systematic and careful management is mandatory. This work aims to define prognostic factors of epistaxis recurrence. MATERIAL AND METHODS: Retrospective review of medical records of patients with epistaxis admitted to our emergency department from January 2012 to December 2016. Data of 1005 patients with idiopathic epistaxis were analysed and independent risk factors for recurrence were determined by multiple logistic regression analysis. RESULTS: Recurrence of epistaxis was found in 303 (30.1%) patients. Patients with recurrent epistaxis were older (p<.001) and more commonly had a history of hypertension (p=.001) and antiplatelet (p=.048) and anticoagulant (p=.001) use than those with episodic epistaxis. Age (adjusted OR 1.21, 95%CI 1.08-1.32, p=.003) and anticoagulant use (adjusted OR 2.68, 95%CI 1.94-3.70, p=.009) were predictors of increased risk of recurrent epistaxis. Gender, alcohol abuse, medical history, active bleeding at admission, unidentified bleeding point or treatment modalities were not associated with recurrence. CONCLUSION: Age and use of anticoagulation drugs were risk factors for recurrence of epistaxis. None of the previously described risk factors for episodic epistaxis were found to increase the risk of recurrence. Knowledge of factors involved in recurrence might provide important information for assessment and management of increased risk patients.

18.
Environ Sci Pollut Res Int ; 26(29): 30426-30443, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31440972

RESUMO

This study has assessed the influence of the origin of air mass on levels of particulate matter (PM10) and chemical composition (SO42- and NO3-) in the air basin of Madrid. A data set of back-trajectories of air mass arriving to this area of study from 15 June 15 2009 to 8 July 2011 has been analyzed. Firstly, the cluster analysis statistical method has been used to group the back-trajectories into 5 sets according to the angle, direction, and speed of the air mass. Afterwards, the synoptic meteorological scenarios associated with each cluster were obtained and interpreted. Subsequently, an analysis was made on the influence of these clusters on the surface levels of particulate pollutants recorded in a regional background station ("El Atazar"), as well as in two urban background stations ("Casa de Campo" and "CIEMAT"). Finally, potential source areas of PM10, SO42-, and NO3- that contributed to the increase in their background levels in the Madrid air basin were detected by analyzing residence times of trajectories. Transport of mineral desert dust is probably the main cause of the increase of regional and urban background levels of PM10 in the Madrid air basin. In the case of SO42-, relatively high levels were registered, associated with air mass coming from Southern Europe and the Mediterranean Sea. In these regions, strong emissions of SO42- are produced due to industrial combustion and maritime traffic. Otherwise, relatively high levels of NO3- were registered during meteorological situations defined by a low baric gradient in the Iberian Peninsula. This meteorological pattern favors the accumulation of emissions from local and regional sources. Besides, the main urban centers of northeastern Europe and industrial areas located in the north African coast were also identified as potential source areas of NO3-. The statistical analysis of the back-trajectories by different methods and the comparison of the results obtained with observational data confirmed that numerous industrial areas in Europe and North Africa, as well as natural ones, such as deserts, had an influence on the regional and urban background levels of mass and chemical composition of particulate matter in the Madrid air basin, under the development of specific synoptic meteorological situations. Graphical abstract.


Assuntos
Poluição do Ar/análise , Compostos Inorgânicos/análise , Material Particulado/análise , África do Norte , Poluentes Atmosféricos/análise , Atmosfera , Poeira/análise , Monitoramento Ambiental/métodos , Indústrias , Região do Mediterrâneo , Mar Mediterrâneo , Conceitos Meteorológicos , Espanha , Análise Espaço-Temporal
19.
Asia Pac J Clin Oncol ; 15(6): 371-376, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31321885

RESUMO

AIM: Intensity-modulated radiotherapy (IMRT) has demonstrated improved local control in extremity soft tissue sarcoma (STS) after limb-sparing surgery compared with three-dimensional conformal radiation therapy. Our purpose was to evaluate sliding-window IMRT (SW-IMRT) and volumetric arc therapy (VMAT) in planning target volume (PTV) coverage and dose to organs-at-risk (OAR). METHODS: Sixteen patients undergoing postoperative RT for lower extremity STS were included. For each patient, one VMAT plan and one SW-IMRT plan were proposed. Both were evaluated using cumulative dose-volume histogram data for OAR and PTVs. Prescribed dose was 66 Gy (2 Gy/fraction) to PTV1 and 56 Gy (1.69 Gy/fraction) to PTV2. OARs contoured were femur, neurovascular bundle, minimum tissue corridor, normal tissue outside PTV2, joint and genitalia. T-Student test was performed. RESULTS: Eleven male (69%) and five female patients (31%) were analyzed. Mean age was 60 years. Both techniques showed optimal target coverage, conformity index (CI) and homogeneity index (HI). VMAT PTV2 CI was 1.13 (mean) ± 0.08 (standard deviation) versus 1.19 ± 0.10 SW-IMRT PTV2 CI (P < 0.05). VMAT PTV1 HI was 0.09 ± 0.01 versus 0.08 ± 0.01 SW-IMRT PTV1 HI (P < 0.05). Regarding OARs, VMAT delivered lower dose to femur, genitalia, normal tissue outside PTV2 and joints. SW-IMRT spared tissue corridor mean dose (10.4 Gy ± 6.8 Gy) versus (14.7 ± 6.5 Gy) VMAT (P < 0.05). CONCLUSIONS: Both techniques achieved great conformity, homogeneity and coverage of PTV. VMAT produced lower dose to OARS and SW-IMRT was superior in sparing dose to normal-tissue-corridor, which could reduce risk of lymphedema.


Assuntos
Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Sarcoma/radioterapia , Neoplasias de Tecidos Moles/radioterapia , Adulto , Idoso , Terapia Combinada , Feminino , Humanos , Salvamento de Membro/métodos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Radioterapia Adjuvante/métodos , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/cirurgia , Coxa da Perna
20.
J Comput Chem ; 40(26): 2248-2283, 2019 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-31251411

RESUMO

The paper collects the answers of the authors to the following questions: Is the lack of precision in the definition of many chemical concepts one of the reasons for the coexistence of many partition schemes? Does the adoption of a given partition scheme imply a set of more precise definitions of the underlying chemical concepts? How can one use the results of a partition scheme to improve the clarity of definitions of concepts? Are partition schemes subject to scientific Darwinism? If so, what is the influence of a community's sociological pressure in the "natural selection" process? To what extent does/can/should investigated systems influence the choice of a particular partition scheme? Do we need more focused chemical validation of Energy Decomposition Analysis (EDA) methodology and descriptors/terms in general? Is there any interest in developing common benchmarks and test sets for cross-validation of methods? Is it possible to contemplate a unified partition scheme (let us call it the "standard model" of partitioning), that is proper for all applications in chemistry, in the foreseeable future or even in principle? In the end, science is about experiments and the real world. Can one, therefore, use any experiment or experimental data be used to favor one partition scheme over another? © 2019 Wiley Periodicals, Inc.

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