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2.
Chaos ; 31(9): 093108, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34598456

RESUMO

In this work, we study the development of vortical structures generated in a rotating cylinder non-homogeneously cooled on the top. In the axisymmetric regime, for moderate vertical temperature differences and any rotation rate, cyclonic and anticyclonic rotations coexist in the flow: a counterclockwise motion at upper levels, giving place to a vertical top-down vortex, and a clockwise rotation at lower levels that generates a spin up motion. For lower rotation rates and high enough vertical temperature differences, only cyclonic top-down vortices survive and get stronger. We perform a force balance analysis to explain the phenomena. In the non-axisymmetric regime, no anticyclonic rotation at the bottom is reported and the cyclonic top-down vortex either disappears or splits up in two top-down vortices, depending on the ambient rotation rate. The intensity of the cooling on the top and how localized this cool region is affect the flow developed. When the horizontal temperature difference on the top is larger than the vertical temperature difference between top and bottom, stable axisymmetric top-down vortices with an inner updraft of warmer air are reported. The more localized the cooling above, the more difficult the development of the inner updraft becomes. Results may contribute to the understanding of the relevance of thermal processes in tornadogenesis.

3.
Clin Exp Immunol ; 204(2): 221-238, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33459349

RESUMO

Patients with rheumatoid arthritis (RA) may be classified as seropositive or seronegative according to the presence of autoantibodies. An abnormal B cell phenotype and function could be one of the main components of the immunopathology of seropositive patients; however, there is little information regarding B cell defects in these patients. This study shows a broad characterization of the B cell phenotype and function in patients with seropositive RA. We focused mainly on the evaluation of subsets, the expression of modulatory molecules of cell activation (CD22, FcÉ£RIIb and FcµR), calcium mobilization, global tyrosine phosphorylation, expression of activation markers, cytokine and immunoglobulin (Ig) production, proliferation and the in-vitro generation of plasma cells. Increased frequency of CD27- IgM- IgD- and CD21- B cells was observed in patients with seropositive RA compared with healthy donors (HD). Decreased expression of CD22 was primarily found in memory B cells of patients with RA regardless of seropositivity. B cells from seropositive patients exhibited normal proliferation, calcium mobilization kinetics and global tyrosine phosphorylation, but showed an increased frequency of CD86+ B cells compared with HD. B cells of seropositive patients secrete less interleukin-10 after in-vitro activation and showed a decreased frequency of plasma cell differentiation and IgM production compared with HD. Our data indicate that patients with seropositive RA have an increased frequency of atypical B cell populations previously associated with chronic activation and antigen exposure. This may result in the observed low responsiveness of these cells in vitro.


Assuntos
Artrite Reumatoide/imunologia , Linfócitos B/imunologia , Adulto , Idoso , Autoanticorpos/imunologia , Diferenciação Celular/imunologia , Citocinas/imunologia , Feminino , Humanos , Isotipos de Imunoglobulinas/imunologia , Memória Imunológica/imunologia , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Fenótipo
6.
Phys Rev E ; 99(3-1): 033109, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30999500

RESUMO

In this paper we use simulations of the magnetohydrodynamic equations coupled with heat to show the generation of magnetic field by the dynamical interaction of a pair of vortices in a fluid electrically conducting within a cylindrical domain nonhomogeneously heated from below, setting in a rotation frame. For large enough rotation rates we show that the formation of a pair of vortices inside the primary whirl gives rise to a magnetic field. The magnetic field has a strong horizontal component, and the magnetic lines go from one vortex to the other.

7.
Can J Gastroenterol Hepatol ; 2019: 3926051, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31929980

RESUMO

Background: Gastroesophageal reflux disease (GERD) is the most frequent chronic gastrointestinal disorder. It is defined as a condition developed when the reflux of gastric contents causes troublesome symptoms (heartburn and regurgitation). This requires adequate treatment since it can lead to long-term complications including esophagus adenocarcinoma. Proton pump inhibitors (PPI) are generally used to treat GERD due to their high-security profile and efficiency on most patients. However, recurrent reflux despite initial treatment is frequent. N-of-1 trial is a study that allows the identification of the best treatment for each patient. The objective of this study is to compare the efficacy of standard dose with double dosage of esomeprazole, to improve the GERD symptoms in a single patient. Methods: A single-patient trial, placebo-controlled, randomized, double-blind, was carried out from September 25th, 2012, to April 26th, 2013. It included one outpatient at the gastroenterology service in a fourth-level hospital, diagnosed with nonerosive reflux disease (NERD). Yet, his symptoms were heartburn and reflux, and his endoscopic results were normal esophageal mucosa, without hiatal hernia, though pathological pH values. A no-obese male without any tobacco or alcohol usage received esomeprazole 40 mg/day and 40 mg/bid for 24 weeks. A standardized gastroesophageal reflux disease questionnaire (GerdQ) was used weekly to evaluate symptom frequency and severity. The consumption of 90% of the capsules was considered as an adequate treatment adherence. D'agostino-Pearson and Wilcoxon test were used to determine normal or nonnormal distribution and compare both treatments, respectively, both with a significant statistical difference of p < 0.05. Results: The patient completed the study with 96% of adherence. The double dosage of esomeprazole did not improve the control of symptoms compared with the standard dosage. Mean symptomatic score was 9.5±0.5 and 10.2±0.6 for each treatment, respectively (p > 0.05). Conclusion: There was no significant improvement in the patient GERD symptoms increasing the dose of oral esomeprazole during the 6 months of study. N-of-1 trials in chronic pathologies including GERD are recommended due to their potential value as systematic methods that evaluate therapies without strong scientific evidence.


Assuntos
Esomeprazol/administração & dosagem , Refluxo Gastroesofágico/tratamento farmacológico , Inibidores da Bomba de Prótons/administração & dosagem , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Projetos de Pesquisa , Resultado do Tratamento
8.
Actas dermo-sifiliogr. (Ed. impr.) ; 109(6): 536-542, jul.-ago. 2018. ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-175616

RESUMO

INTRODUCCIÓN: A pesar de que los únicos fármacos con indicación aprobada en nuestro país para la alopecia androgénica (AGA) son minoxidil tópico y finasterida oral, es común la utilización de numerosas terapias fuera de indicación, provocando una gran variabilidad en el manejo de estos pacientes. El objetivo principal de este trabajo fue describir los hábitos de prescripción de los dermatólogos en España en AGA masculina (MAGA) y AGA femenina (FAGA). MATERIAL Y MÉTODOS: Estudio descriptivo transversal mediante cuestionarios digitales autocumplimentados por dermatólogos que ejercen en territorio español. RESULTADOS: Se incluyeron las respuestas de un total de 241 dermatólogos. En MAGA los tratamientos más utilizados fueron en este orden: minoxidil tópico (98%), finasterida oral (96%), nutricosméticos (44%), finasterida tópica (37%), dutasterida oral (33%), plasma rico en plaquetas (14%) y láser de baja potencia (8%). En FAGA premenopáusica: minoxidil tópico (98%), anticonceptivos orales (81%), nutricosméticos (72%), acetato de ciproterona (58%), finasterida oral (39%), finasterida tópica (39%), espironolactona (27%), plasma rico en plaquetas (20%), dutasterida oral (20%), flutamida oral (18%) y láser de baja potencia (7%). En FAGA posmenopáusica: minoxidil tópico (98%), finasterida oral (84%), nutricosméticos (68%), finasterida tópica (50%), dutasterida oral (35%), plasma rico en plaquetas (21%), espironolactona (16%), acetato de ciproterona (16%), flutamida oral (9%) y láser de baja potencia (9%). Como limitaciones de nuestro estudio, no se incluyeron terapias novedosas para AGA como minoxidil oral o microinyecciones de dutasterida. CONCLUSIONES: Los agentes terapéuticos más utilizados en MAGA y FAGA posmenopáusica por los dermatólogos en España fueron minoxidil tópico, finasterida oral y nutricosméticos, mientras que en FAGA premenopáusica fueron minoxidil tópico, anticonceptivos orales y nutricosméticos


BACKGROUND: Topical minoxidil and oral finasteride are the only drugs approved for the treatment of androgenetic alopecia (AGA) in Spain. However, the management of this condition is highly variable because numerous treatments are used off-label. The main aim of this study was to describe the prescribing habits of dermatologists in Spain for male AGA (MAGA) and female AGA (FAGA). MATERIAL AND METHODS: Descriptive cross-sectional study using online questionnaires completed by dermatologists working in Spain. RESULTS: The responses of 241 dermatologists were analyzed. The most common treatments prescribed for MAGA were minoxidil (98%), oral finasteride (96%), nutricosmetics (44%), topical finasteride (37%), oral dutasteride (33%), platelet-rich plasma (14%), and low-level laser therapy (8%). For premenopausal FAGA, the most common treatments were topical minoxidil (98%), oral contraceptives (81%), nutricosmetics (72%), cyproterone acetate (58%), oral finasteride (39%), topical finasteride (39%), spironolactone (27%), platelet-rich plasma (20%), oral dutasteride (20%), oral flutamide (18%), and low-level laser therapy (7%). Finally, for postmenopausal FAGA, the most common treatments prescribed were topical minoxidil (98%), oral finasteride (84%), nutricosmetics (68%), topical finasteride (50%), oral dutasteride (35%), platelet-rich plasma (21%), spironolactone (16%), cyproterone acetate (16%), oral flutamide (9%), and low-level laser therapy (9%). A limitation of our study is that we did not analyze novel AGA treatments such as oral minoxidil and dutasteride mesotherapy. CONCLUSIONS:The most common treatments prescribed for AGA by dermatologists in Spain are topical minoxidil, oral finasteride, and nutricosmetics for MAGA and postmenopausal FAGA and topical minoxidil, oral contraceptives, and nutricosmetics for premenopausal FAGA


Assuntos
Humanos , Prescrições/estatística & dados numéricos , Alopecia/epidemiologia , Fluxometria por Laser-Doppler/métodos , Dermatologistas/estatística & dados numéricos , Estudos Transversais , Alopecia/terapia , Finasterida/administração & dosagem , Dutasterida/administração & dosagem , Minoxidil/administração & dosagem , Inquéritos e Questionários , Espanha/epidemiologia
10.
Actas Dermosifiliogr (Engl Ed) ; 109(6): 536-542, 2018.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29656764

RESUMO

BACKGROUND: Topical minoxidil and oral finasteride are the only drugs approved for the treatment of androgenetic alopecia (AGA) in Spain. However, the management of this condition is highly variable because numerous treatments are used off-label. The main aim of this study was to describe the prescribing habits of dermatologists in Spain for male AGA (MAGA) and female AGA (FAGA). MATERIAL AND METHODS: Descriptive cross-sectional study using online questionnaires completed by dermatologists working in Spain. RESULTS: The responses of 241 dermatologists were analyzed. The most common treatments prescribed for MAGA were minoxidil (98%), oral finasteride (96%), nutricosmetics (44%), topical finasteride (37%), oral dutasteride (33%), platelet-rich plasma (14%), and low-level laser therapy (8%). For premenopausal FAGA, the most common treatments were topical minoxidil (98%), oral contraceptives (81%), nutricosmetics (72%), cyproterone acetate (58%), oral finasteride (39%), topical finasteride (39%), spironolactone (27%), platelet-rich plasma (20%), oral dutasteride (20%), oral flutamide (18%), and low-level laser therapy (7%). Finally, for postmenopausal FAGA, the most common treatments prescribed were topical minoxidil (98%), oral finasteride (84%), nutricosmetics (68%), topical finasteride (50%), oral dutasteride (35%), platelet-rich plasma (21%), spironolactone (16%), cyproterone acetate (16%), oral flutamide (9%), and low-level laser therapy (9%). A limitation of our study is that we did not analyze novel AGA treatments such as oral minoxidil and dutasteride mesotherapy. CONCLUSIONS: The most common treatments prescribed for AGA by dermatologists in Spain are topical minoxidil, oral finasteride, and nutricosmetics for MAGA and postmenopausal FAGA and topical minoxidil, oral contraceptives, and nutricosmetics for premenopausal FAGA.


Assuntos
Alopecia/tratamento farmacológico , Dermatologia , Padrões de Prática Médica , Estudos Transversais , Prescrições de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Masculino , Prática Privada , Setor Público , Autorrelato , Espanha
12.
J Radiol Prot ; 38(2): 716-730, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29532785

RESUMO

This work describes the radiation characterisation and dosimetric measurements performed on the low-energy micromachining station of the femtosecond STELA (Santiago TErawatt LAser) at the University of Santiago de Compostela (Spain). For this aim, ionisation chambers, solid state detectors, and radiochromic films were used. The results show the emission of pulsed x-ray produced by laser-accelerated electrons from the ablated material exhibiting both bremsstrahlung and characteristic radiation. Although this radiation was produced unintentionally, a high superficial dose rate can be achieved. This radiation can be successfully stopped using small shielding to protect personnel from its effects. Based on the results of this work, the yearly dose equivalent after installing the shielding was negligible.


Assuntos
Terapia a Laser/métodos , Radiometria/métodos
15.
J Eur Acad Dermatol Venereol ; 31(10): 1739-1745, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28426907

RESUMO

BACKGROUND: Frontal fibrosing alopecia (FFA) is a chronic scarring alopecia with an unpredictable evolution. There are no current classifications of this disease that may predict its prognosis. OBJECTIVE: To analyse the differences in clinical presentation and evolution of FFA patients and to create a clinical and prognostic classification. METHODS: We conducted a retrospective analytical study of FFA patients. Clinical characteristics of frontal hairline recession were used as the sorting variable between patterns of presentation. A cohort of 106 patients homogenously treated with oral dutasteride and topical corticosteroid was followed 12 months. RESULTS: In all, 242 female patients with a mean age of 61.4 years were included. Patients were classified into three clinical patterns [118 (48.8%) patients as pattern I (linear), 109 patients (45%) as pattern II (diffuse) and 15 patients (6.2%) as pattern III (double line)]. Stabilization was achieved in 37.3% of the 106 patients treated with oral dutasteride and topical corticosteroid. Pattern III patients had less hairline recession and eyebrow involvement at the diagnosis and after treatment. LIMITATIONS: Retrospective design. CONCLUSIONS: Frontal fibrosing alopecia patients can be classified into three different clinical patterns with different prognosis. Pattern III patients have the best prognosis, while pattern II patients have the worst prognosis.


Assuntos
Alopecia/classificação , Corticosteroides/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Alopecia/tratamento farmacológico , Alopecia/patologia , Dutasterida/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
16.
Med Phys ; 43(7): 4142, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27370134

RESUMO

PURPOSE: The high mass density and low mobilities of charge carriers can cause important recombination in liquid-filled ionization chambers (LICs). Saturation correction methods have been proposed for LICs. Correction methods for pulsed irradiation are based on Boag equation. However, Boag equation assumes that the charge ionized by one pulse is fully collected before the arrival of the next pulse. This condition does not hold in many clinical beams where the pulse repetition period may be shorter than the charge collection time, causing overlapping between charge carriers ionized by different pulses, and Boag equation is not applicable there. In this work, the authors present an experimental and numerical characterization of collection efficiencies in LICs beyond the Boag limit, with overlapping between charge carriers ionized by different pulses. METHODS: The authors have studied recombination in a LIC array for different dose-per-pulse, pulse repetition frequency, and polarization voltage values. Measurements were performed in a Truebeam Linac using FF and FFF modalities. Dose-per-pulse and pulse repetition frequency have been obtained by monitoring the target current with an oscilloscope. Experimental collection efficiencies have been obtained by using a combination of the two-dose-rate method and ratios to the readout of a reference chamber (CC13, IBA). The authors have also used numerical simulation to complement the experimental data. RESULTS: The authors have found that overlap significantly increases recombination in LICs, as expected. However, the functional dependence of collection efficiencies on the dose-per-pulse does not change (a linear dependence has been observed in the near-saturation region for different degrees of overlapping, the same dependence observed in the nonoverlapping scenario). On the other hand, the dependence of collection efficiencies on the polarization voltage changes in the overlapping scenario and does not follow that of Boag equation, the reason being that changing the polarization voltage also affects the charge collection time, thus changing the amount of overlapping. CONCLUSIONS: These results have important consequences for saturation correction methods for LICs. On one hand, the two-dose-rate method, which relies on the functional dependence of the collection efficiencies on dose-per-pulse, can also be used in the overlapping situation, provided that the two measurements needed to feed the method are performed at the same pulse repetition frequency (monitor unit rate). This result opens the door to computing collection efficiencies in LICs in many clinical setups where charge overlap in the LIC exists. On the other hand, correction methods based on the voltage-dependence of Boag equation like the three-voltage method or the modified two-voltage method will not work in the overlapping scenario due to the different functional dependence of collection efficiencies on the polarization voltage.


Assuntos
Radiometria/instrumentação , Radiometria/métodos , Algoritmos , Simulação por Computador , Modelos Teóricos , Aceleradores de Partículas , Incerteza
17.
Phys Rev E ; 93(1): 013117, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26871164

RESUMO

The appearance, evolution, and disappearance of periodic and quasiperiodic dynamics of fluid flows in a cylindrical annulus locally heated from below are analyzed using nonlinear simulations. The results reveal a route of the transition from a steady axisymmetric vertical vortex to a chaotic flow. The chaotic flow regime is reached after a sequence of successive supercritical Hopf bifurcations to periodic, quasiperiodic, and chaotic flow regimes. A scenario similar to the Ruelle-Takens-Newhouse scenario is verified in this convective flow. In the transition to chaos we find the appearance of subvortices embedded in the primary axisymmetric vortex, flows where the subvortical structure strengthens and weakens, that almost disappears before reforming again, leading to a more disorganized flow to a final chaotic regime. Results are remarkable as they connect to observations describing formation, weakening, and virtual disappearance before revival of subvortices in some atmospheric swirls such as dust devils.

18.
Phys Med Biol ; 59(11): 2705-12, 2014 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-24787030

RESUMO

The use of liquid ionization chambers in radiotherapy has grown during the past few years. While for air ionization chambers the k(TP) correction for air mass density due to pressure and temperature variations is well known, less work has been done on the case of liquid ionization chambers, where there is still the need to take into account the influence of temperature in the free ion yield. We have measured the PTW microLion isooctane-filled ionization chamber temperature dependence in a ~ ±10 °C interval around the standard 20 °C room temperature for three operation voltages, including the manufacturer recommended voltage, and two beam qualities, (60)Co and 50 kV x-rays. Within the measured temperature range, the microLion signal exhibits a positive linear dependence, which is around 0.24% K(-1) at 800 V with (60)Co irradiation. This effect is of the same order of magnitude as the T dependence found in air ionization chambers, but its nature is completely different and its sign opposite to that of an air chamber. Onsager theory has been used to model the results and is consistent with this linear behaviour. However, some inconsistencies in the modelling of the 50 kV x-ray results have been found that are attributed to the failure of Onsager's isolated pair assumption for such radiation quality.


Assuntos
Radiometria/instrumentação , Temperatura
19.
Chaos ; 24(4): 043116, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25554036

RESUMO

This paper shows the influence of the inner radius on the stability and intensity of vertical vortices, qualitatively similar to dust devils and cyclones, generated in a cylindrical annulus non-homogeneously heated from below. Little relation is found between the intensity of the vortex and the magnitude of the inner radius. Strong stable vortices can be found for both small and large values of the inner radius. The Rankine combined vortex structure, that characterizes the tangential velocity in dust devils, is clearly observed when small values of the inner radius and large values of the ratio between the horizontal and vertical temperature differences are considered. A contraction on the radius of maximum azimuthal velocity is observed when the vortex is intensified by thermal mechanisms. This radius becomes then nearly stationary when frictional force balances the radial inflow generated by the pressure drop in the center, despite the vortex keeps intensifying. These results connect with the behavior of the radius of the maximum tangential wind associated with a hurricane.

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