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1.
J Phys Condens Matter ; 36(25)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38498947

RESUMO

To describe the way complexity emerges in seemingly simple systems of nature, requires one to attend to two principal questions: how complex patterns appear spontaneously and why a single system can accommodate their inexhaustible variety. It is commonly assumed the pattern formation phenomenon is related to the competition of several types of interactions with disparate length scales. These multi-scale interactions also lead to frustration within the system, resulting in the existence of a manifold of configurations-patterns with qualitatively distinct morphologies. This work explores an alternative approach through a mechanism that leads to a wide range of intricate and topologically non-trivial patterns. The mechanism is described by the self-dual Ginzburg-Landau theory and, possibly, other Maxwell-Higgs models. It gives rise to unique spatial flux and condensate spatial profiles observed in superconductors between the two conventional superconductivity types I and II.

2.
J Phys Chem Lett ; 15(9): 2573-2579, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38417042

RESUMO

Surface superconductivity, wherein electron pairing occurs at material surfaces or interfaces, has attracted a remarkable amount of attention since its discovery. Recent theoretical predictions have unveiled increased critical temperatures, especially at the surfaces of certain compounds and/or structures. The notion of "surface ordering" has been advanced to elucidate this phenomenon. Employing the framework of self-consistent Bogoliubov-de Gennes equations and a model incorporating correlated disorder, our study demonstrates the persistence of the surface ordering effect in the presence of weak to moderate bulk disorder. Intriguingly, our findings indicate that under moderate disorder conditions the surface critical temperature can be further increased, depending on the intensity and correlation of the disorder.

3.
J Phys Chem Lett ; 14(24): 5657-5664, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37311195

RESUMO

Using the tight-binding Bogoliubov-de Gennes formalism, we describe the influence of the surface potential on the superconducting critical temperature at the surface. Surface details are taken into account within the framework of the self-consistent Lang-Kohn effective potential. The regimes of strong and weak coupling of superconducting correlations are considered. Our study reveals that, although the enhancement of the surface critical temperature, originating from the enhancement of the localized correlation due to the constructive interference between quasiparticle bulk orbits, can be sufficiently affected by the surface potential, this influence, nonetheless, strongly depends on the bulk material parameters, such as the effective electron density parameter and Fermi energy, and is likely to be negligible for some materials, in particular for narrow-band metals. Thus, superconducting properties of a surface can be controlled by the surface/interface potential properties, which offer an additional tuning knob for the superconducting state at the surface/interface.

4.
J Phys Chem Lett ; 12(17): 4172-4179, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33896186

RESUMO

Cluster formation is a focus of interdisciplinary research in both chemistry and physics. Here we discuss the exotic example of this phenomenon in the vortex matter of a thin superconductor. In superconducting films, the clustering takes place because of particular properties of the vortex interactions in the crossover or intertype regime between superconductivity types I and II. These interactions are controlled by the two parameters that are responsible for the crossover, Ginzburg-Landau parameter κ, which specifies the superconducting material of the film, and film thickness d, which controls effects due to stray magnetic fields outside the sample. We demonstrate that their competition gives rise to a complex spatial dependence of the interaction potential between vortices, favoring the formation of chainlike vortex clusters.

5.
J Phys Condens Matter ; 33(10): 105902, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33285526

RESUMO

We demonstrate that the presence of edges in a superconducting film made of a type-I/type-II bilayer stabilizes type-II/type-I hybrid (inter-type) flux patterns, as vortex clusters, chains, and gel phase. These patterns are very sensitive to primary parameters such as applied magnetic field, layer coupling, and temperature. Thus, the magnetization versus temperature curves, M(T), for many values of coupling were used to estimate the strength of the layer couplings, and also as a guide for obtaining sequentially the flux patterns. We also show that the effect of the borders on the unrestricted states is to shift them to states of higher density, since they introduce extra compression on the vortex matter. For a low layer coupling regime, we observe an unusual magnetic response where few partial vortices (partial in a sense they miss the contribution of the type I part), repelling each other and bounded to the surfaces, populate one layer leaving the other empty. We expect that the predicted flux configurations can stimulate experimentalists in trying to observe them by direct imaging techniques.

6.
J Mater Sci Mater Med ; 31(12): 121, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33247774

RESUMO

Avulsion of the nail plate is the most accomplished surgical procedure among the nail apparatus surgeries. Since it is not possible to use the removed nail to cover the nail bed, some materials have been suggested, however, they are generally not available for use and often at a high cost. To evaluate the use of Bacterial Cellulose (BC) dressing as a biological nail (Bio-Nail) after partial or total avulsion of the nail plate. Twenty-six candidates for nail avulsion, were randomized into two groups: Control, using Vaseline with gauze (11 patients) and Experimental group, BC group, using the Bio-Nail (15 patients). The patients were followed up during the 180-day period. The distribution of the patients in the groups was homogeneous for both sociodemographic and clinical data. The occurrence of infection (1 case in the control group) was not statistically relevant. The BC group had lower pain intensity (p = 0.011) with earlier temporal resolution when compared to the control group (p = 0.003). The BC group presented earlier reepithelization (p = 0.022) and better quantitative (p = 0.021) and qualitative conditions (p = 0.011) for the exudate. Regarding satisfaction, all the patients were satisfied. Good preservation of the nail plate area was observed in the BC group at the end of the 180-day period (p = 0.024). Average time of BC dressing permanence was 16.4 ± 7.1 days. BC showed to be appropriate as a dressing after partial or total avulsion of the nail plate. BC is a Bio-Nail promising for nail bed healing.


Assuntos
Curativos Biológicos , Celulose/química , Avulsões Cutâneas/terapia , Unhas/lesões , Unhas/cirurgia , Adolescente , Adulto , Idoso , Bactérias/química , Brasil , Celulose/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Unhas/patologia , Resultado do Tratamento , Cicatrização/fisiologia , Adulto Jovem
7.
J Phys Condens Matter ; 32(45): 455702, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32688355

RESUMO

There is a tacit assumption that multiband superconductors are essentially the same as multigap superconductors. More precisely, it is usually assumed that the number of excitation gaps in the single-particle energy spectrum of a uniform superconductor (i.e. number of peaks in the density of states of the superconducting electrons) determines the number of contributing bands in the corresponding superconducting model. Here we demonstrate that contrary to this widely accepted viewpoint, the superconducting magnetic properties are sensitive to the number of contributing bands even when the spectral gaps are degenerate and cannot be distinguished. In particular, we find that the crossover between superconductivity types I and II-the intertype regime-is strongly affected by the difference between characteristic lengths of multiple contributing condensates. The reason for this is that condensates with diverse characteristic lengths, when coexisting in one system, interfere constructively or destructively, which results in multi-condensate magnetic phenomena regardless of the presence/absence of the multigap spectrum of a superconducting multiband material.

8.
BMC Health Serv Res ; 20(1): 344, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321489

RESUMO

BACKGROUND: to understand if patients seen at Centro Hospitalar Psiquiátrico de Lisboa (CHPL) live in geographical clusters or randomly throughout the city, as well as determine their access to the psychiatric hospital and primary care facilities (PCF). METHODS: spatial autocorrelation statistics were performed (queen criterion of contiguity), regarding all patients observed at CHPL in 2017 (at the census subsection level), and considering not only their overall number but also main diagnosis, and admission to the psychiatric ward - voluntary or compulsory. Distance to the hospital and to the closest PCF was measured (for each patient and the variables cited above), and the mean values were compared. Finally, the total number of patients around each PCF was counted, considering specified radius sizes of 656 and 1000 m. RESULTS: All 5161 patients (509 psychiatric admissions) were geolocated, and statistical significance regarding patient clustering was found for the total number (p-0.0001) and specific group of disorders, namely Schizophrenia and related disorders (p-0.007) and depressive disorders (p-0.0002). Patients who were admitted in a psychiatric ward live farther away from the hospital (p-0.002), with the compulsory admissions (versus voluntary ones) living even farther (p-0.004). Furthermore, defining a radius of 1000 m for each PCF allowed the identification of two PCF with more than 1000 patients, and two others with more than 800. CONCLUSIONS: as patients seem to live in geographical clusters (and considering PCFs with the highest number of them), possible locations for the development of programs regarding mental health treatment and prevention can now be identified.


Assuntos
Serviços Comunitários de Saúde Mental , Acessibilidade aos Serviços de Saúde , Atenção Primária à Saúde , Adulto , Feminino , Hospitalização/estatística & dados numéricos , Hospitais Psiquiátricos/estatística & dados numéricos , Humanos , Masculino , Transtornos Mentais/epidemiologia , Transtornos Mentais/terapia , Portugal/epidemiologia , Estudos Retrospectivos , Análise Espacial
9.
J Phys Condens Matter ; 32(7): 075403, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-31675734

RESUMO

Superconducting films are usually regarded as type II superconductors even when they are made of a type I material. The reason is the presence of stray magnetic fields that stabilize the vortex matter by inducing long-range repulsive interactions between vortices. While very thin films indeed reach this limit, there is a large interval of thicknesses where magnetic properties of superconducting films cannot be classified as either of the two conventional superconductivity types. Recent calculations revealed that in this interval the system exhibits spontaneous formation of magnetic flux-condensate patterns and superstructures appearing due to the interplay between the long-range stray field effects and proximity to the Bogomolnyi self-duality point. These calculations were based on the periodic in-plane boundary conditions which, as is well known from classical electrodynamics, for systems with long-range interactions can lead to field distortions and considerable discrepancies between results of different calculation methods. Here we demonstrate that similar spontaneous patterns are obtained for superconducting films with open in-plane boundary conditions (vanishing in-plane currents perpendicular to the edges of the finite film) and thus the phenomenon is not an artefact of chosen boundary conditions.

10.
Waste Manag ; 94: 39-48, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31279394

RESUMO

The construction sector has been using supplementary materials in concrete production worldwide, such as coal fly ash. Nowadays, several sub/products or wastes have been studied to be incorporated in construction materials, and one of those wastes is biomass fly ash. However, using high volumes of these materials has some drawbacks, one of them being carbonation. In order to understand phenomena such as this, it is important to study the interaction between the additions and hydration of cement. This paper focuses on the study of hydration and carbonation of cementitious pastes containing biomass fly ash and/or coal fly ash by using thermogravimetric analysis and X-ray diffraction analysis and by accelerated carbonation tests. BFA present different chemical and mineralogical composition than CFA. The results show that incorporating biomass fly ash into construction materials has a similar carbonation behaviour to coal fly ash. Biomass fly ash seems to give some extra alkalinity to the mixtures, and this may present benefits to the construction materials and for the ash management.


Assuntos
Cinza de Carvão , Carvão Mineral , Biomassa , Carbono , Materiais de Construção , Reciclagem
11.
Rev. Soc. Cardiol. Estado de Säo Paulo ; 29(Suppl. 2b): 131-131, Jun. 2019.
Artigo em Português | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1009409

RESUMO

INTRODUÇÃO: Mixomas, embora raros, são os tumores cardíacos benignos mais comuns, com sintomas, alterações laboratoriais e eletrocardiográficas (ECG) inespecíficas, mimetizando diversas patologias. Este estudo reúne nossa experiência de 36 anos com portadores de mixoma, com objetivo de traçar o perfil clínico e evolutivo dessa doença cujo diagnóstico costuma ser desafiante. MÉTODOS: Foram analisados retrospectivamente 78 casos de pacientes (p) com mixoma cardíaco, acompanhados serviço terciário, de 1982 a 2018. Análise estatística: testes exatos de Fisher, t de Student para amostras independentes e não-paramétrico de Mann-Whitney. Valores de p<0,05 indicaram significância estatística. RESULTADOS: A média de idade ao diagnóstico foi de 54,1 ± 13,4 anos, 72% masculinos e 54% hipertensos. O sítio do tumor mais comum foi o átrio esquerdo (89%) e tinham tamanho médio de 83,0 ± 74,2 cm3. Acometimento valvar associado ocorreu em 29p, geralmente de valva mitral (78%), mais frequente nos tumores maiores (p=0,003), embora sem relação direta com o grau de acometimento (p=0,362). Dois terços relataram dispneia e 35% sintomas de insuficiência cardíaca (IC), ocorrendo mais frequentemente nos tumores maiores em comparação àqueles p sem estes sintomas, com significância estatística (p=0,012 para dispneia; p=0,002 para IC). 14 p (18%) sofreram complicações embólicas (acidente vascular encefálico (AVC) ou infarto agudo do miocárdio (IAM)) previamente ao diagnóstico, sem relação com o tamanho do tumor (p=0,307). Apesar de 94% terem ritmo sinusal no ECG, em quase metade dos pacientes (33 casos) viu-se sinais de sobrecarga atrial. A exérese do mixoma foi realizada em média 5,2 meses após o diagnóstico, com média de internação hospitalar de 13,4 dias. Apenas 9 casos necessitaram de plastia ou troca valvar. À histopatologia, a maioria eram de consistência gelatinosa (80%), superfície vilosa (74%) e pedunculados (77%). Não houve associação entre as características histológicas e o risco de complicações embólicas (p>0,05). Os pacientes foram seguidos em média por 7,5 ± 7,3 anos e 96% relataram melhora clínica após a cirurgia. Dois pacientes apresentaram eventos cardiovasculares (AVC e IAM) no pós-operatório tardio e somente 1 paciente apresentou recorrência do tumor. CONCLUSÃO: A maioria dos p com mixomas são sintomáticos e costumam ter alterações no ECG. Fenômenos tromboembólicos foram frequentes e não relacionados com tamanho e características histológicas do tumor, devendo-se cogitar anticoagulação nestes p. (AU)


Assuntos
Humanos , Neoplasias Cardíacas , Mixoma
12.
Sci Adv ; 5(10): eaaw1949, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31976364

RESUMO

While machine learning has been making enormous strides in many technical areas, it is still massively underused in transmission electron microscopy. To address this, a convolutional neural network model was developed for reliable classification of crystal structures from small numbers of electron images and diffraction patterns with no preferred orientation. Diffraction data containing 571,340 individual crystals divided among seven families, 32 genera, and 230 space groups were used to train the network. Despite the highly imbalanced dataset, the network narrows down the space groups to the top two with over 70% confidence in the worst case and up to 95% in the common cases. As examples, we benchmarked against alloys to two-dimensional materials to cross-validate our deep-learning model against high-resolution transmission electron images and diffraction patterns. We present this result both as a research tool and deep-learning application for diffraction analysis.

13.
Exp Parasitol ; 192: 46-51, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30031122

RESUMO

The cross-reaction in the diagnosis results is a serious problem, leading to an incorrect treatment and several injuries to patients. The Trypanosoma rangeli and Trypanosoma cruzi belong to the genus Trypanosoma, but the Trypanosoma rangeli is a non-pathogenic parasite to humans. While Trypanosoma cruzi is the etiological agent of Chagas' disease, which affects circa 2-3 million people and more than 6000 deaths annually in Brazil. The Leishmania chagasi causes infectious disease known as visceral leishmaniasis. This diseases have in common the crossed antigenic reaction promoted by serological tests and its differentiation is relevant for epidemiological studies and clinical practice. In this study the Fourier Transform Infrared (FT-IR) Spectroscopy was used to differentiate these microorganisms, which were cultivated and the spectra analyzed. Data analysis were performed by Gaussian curve fitting and multivariate statistical analysis. The cluster analysis have shown four specific regions to identify the microorganisms. The first three PCs of principal component analysis associated to linear discriminant were able to classify 95.6% of the parasites using cross-validation. The curve fitting method showed the quantitative differentiation among L. chagasi, T. cruzi, and T. rangeli species in the vibrational regions of polysaccharides, amide III, lipid esters, and fatty acid.


Assuntos
Leishmania infantum/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Trypanosoma cruzi/isolamento & purificação , Trypanosoma rangeli/isolamento & purificação , Amidas/análise , Análise por Conglomerados , Reações Cruzadas , Análise Discriminante , Ésteres/análise , Ácidos Graxos/análise , Leishmania infantum/química , Leishmania infantum/classificação , Leishmania infantum/genética , Modelos Lineares , Análise Multivariada , Distribuição Normal , Polissacarídeos/análise , Análise de Componente Principal , Trypanosoma cruzi/química , Trypanosoma cruzi/classificação , Trypanosoma cruzi/genética , Trypanosoma rangeli/química , Trypanosoma rangeli/classificação , Trypanosoma rangeli/genética
14.
Rev. andal. med. deporte ; 10(3): 125-131, sept. 2017. tab, graf
Artigo em Inglês | IBECS | ID: ibc-165976

RESUMO

Objective. Evaluate isokinetic muscle performance of the hamstring and quadriceps muscles in male handball players, as well as verify the effect of handball match on salivary cortisol and immunoglobulin A by Fourier transform infrared spectroscopy. Method. The isokinetic parameters evaluated were peak torque, fatigue index, and hamstring/quadriceps peak torque ratio. Saliva samples were collected before and after a simulated handball match, as well as after 2 h of recovery. Analysis of saliva by Fourier transform infrared spectroscopy was based on infrared region of the pure substances (cortisol and human salivary cortisol and immunoglobulin A). Results. No significant difference was found between the non-dominant and dominant lower limb at 60 and 180°/s, in extension and flexion for variables of peak torque and fatigue index. The hamstring/quadriceps ratio at 60°/s was lower than at 180°/s. The main absorption bands of cortisol are in the region (1180-955cm−1) and human salivary cortisol and immunoglobulin A bands in the region (1584-1489cm−1). The saliva samples collected before and after match showed no significant difference. The variation of cortisol per playing positions was positively correlated with session rate of perceived exertion. Conclusions. The handball players had good muscle performance of the lower limbs in the isokinetic evaluation. The Fourier transform infrared spectroscopy analysis identified the main absorption bands of cortisol and salivary cortisol and immunoglobulin A, as well as playing positions that demand higher stress levels, through changes of bands related to salivary cortisol (AU)


Objetivo. Evaluar el rendimiento muscular isocinético de los isquiotibiales y los cuádriceps en jugadores de balonmano masculino, así como examinar el efecto de un partido de balonmano en el cortisol salival y la inmunoglobulina A por espectroscopia infrarroja con transformada de Fourier. Método. Los parámetros isocinéticos evaluados fueron el torque máximo, el índice de fatiga y la razón de torque máximo isquiotibial/cuádriceps. Las muestras de saliva se recogieron antes y después de un partido de balonmano simulado y tras 2h de recuperación. El análisis de la saliva por espectroscopia infrarroja con transformada de Fourier se basó en las regiones de infrarrojos de sustancias puras (cortisol, cortisol salival y la inmunoglobulina A humana). Resultados. No hubo diferencias significativas entre los miembros inferiores dominante y no dominante a 60 y 180°/s, en extensión y flexión para torque máximo e índice de fatiga. La razón isquiotibial/cuádriceps a 60°/s fue inferior que a 180°/s. Las principales bandas de absorción de cortisol se encuentran en la región (1180-955cm−1) y cortisol salival e inmunoglobulina A en la región (1584-1489cm−1). Las muestras de saliva recogidas antes y después del partido no muestran diferencias significativas. La variación de cortisol por la posición de juego se correlacionó positivamente con la tasa de esfuerzo percibido en la sesión. Conclusiones. Los jugadores de balonmano mostraron buen rendimiento muscular de los miembros inferiores en la evaluación isocinética. El análisis por espectroscopia infrarroja con transformada de Fourier identificó las principales bandas de cortisol y cortisol salival e inmunoglobulina A, así como las posiciones de juego que requieren mayores niveles de estrés, por medio de los cambios en las bandas relacionadas con el cortisol salival (AU)


Objetivo. Avaliar o desempenho muscular isocinético dos flexores e extensores do joelho em jogadores de handebol do sexo masculino, bem como verificar o efeito da partida de handebol sobre o cortisol salivar e imunoglobulina A por espectroscopia no infravermelho. Método. Os seguintes parâmetros foram avaliados com dinamômetro isocinético: o torque máximo, índice de fadiga e razão agonista/antagonista. Amostras de saliva foram coletadas antes e depois de uma partida de handebol simulada, bem como depois de 2 horas de recuperação. Análise de saliva por espectroscopia no infravermelho foi baseada na região do infravermelho das substâncias puras (cortisol e imunoglobulina A humano). Resultados. Não foi encontrada diferença significativa entre dos membros inferiores não-dominante e dominante em 60 e 180°/s, em extensão e flexão para variáveis do torque máximo e índice de fadiga. A relação flexores/extensores do joelho a 60°/s foi inferior a 180°/s. As principais bandas de absorção do cortisol estão na região (1180-955 cm-1) e bandas de imunoglobulina A humana na região (1584-1489cm-1). As amostras de saliva coletadas antes e depois do jogo não apresentaram diferenças significativas. A variação do cortisol por posições de jogo foi positivamente correlacionada com a taxa de percepção subjetiva de esforço da sessão. Conclusões. Os jogadores de handebol tiveram bom desempenho muscular dos membros inferiores na avaliação isocinética. A análise espectroscopia no infravermelho identificou as principais bandas de absorção de cortisol e imunoglobulina A, bem como as posições de jogo que exigem níveis mais elevados de estresse, através de mudanças de bandas relacionadas com cortisol salivar (AU)


Assuntos
Humanos , Masculino , Adulto , Esportes/fisiologia , Desempenho Atlético/fisiologia , Análise Espectral/métodos , Imunoglobulina A/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Extremidade Inferior/fisiologia , Saliva/fisiologia
15.
Sci Rep ; 7: 40148, 2017 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-28091522

RESUMO

Under irradiation, chemical species can redistribute in ways not expected from equilibrium behavior. In oxide-dispersed ferritic alloys, the phenomenon of irradiation-induced Cr redistribution at the metal/oxide interfaces has drawn recent attention. Here, the thermal and irradiation stability of the FeCr/Y2O3 interface has been systematically studied. Trilayer thin films of 90 nm Fe - 20 at.% Cr (1st layer)/100 nm Y2O3 (2nd layer)/135 nm Fe - 20 at.% Cr (3rd layer) were deposited on MgO substrates at 500 °C. After irradiation, Cr diffuses towards and enriches the FeCr/Y2O3 interface. Further, correlated with Cr redistributed into the oxide, an amorphous layer is generated at the interface. In the Y2O3 layer, the original cubic phase is observed to transform to the monoclinic phase after irradiation. Meanwhile, nanosized voids, with relatively larger size at interfaces, are also observed in the oxide layer. First-principles calculations reveal that Cr substitution of Y interstitials in Y2O3 containing excess Y interstitials is favored and the irradiation-induced monoclinic phase enhances this process. Our findings provide new insights that may aid in the development of irradiation resistant oxide-dispersed ferritic alloys.

16.
Andrologia ; 49(5)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27401787

RESUMO

Male fertility can be evaluated through complete semen analysis. Plants belonging to the Tribulus genus are known for their role in enhancing sex hormone levels and semen quality. The aim of this study was to evaluate the effects of T. terrestris on semen quality and physiological parameters. Sixty-five men with abnormal semen evaluation were included in this study, in which they were prescribed with oral administration of Androsten® (250 mg of Tribulus terrestris dried extract per capsule). Body fat percentage, lean muscle mass gain, fluctuation in steroid hormone levels and all semen parameters were analysed during the period of treatment. The results demonstrated that decrease in the percentage of body fat and increase in lean mass were significant, as well as increase in dihydrotestosterone levels. Complete semen analysis evaluated at the end of treatment showed significant enhancement in sperm concentration, motility and liquefaction time. Protodioscin, the main phytochemical agent of the Tribulus genus, acts on sertoli cells, germ cell proliferation and growth of seminiferous tubules. This component is known to convert testosterone into dihydrotestosterone, which plays important roles in male attributes. Our results indicate the therapeutic use of Tribulus terrestris by men presenting altered semen parameters, and/or undergoing infertility treatment.


Assuntos
Composição Corporal/efeitos dos fármacos , Infertilidade Masculina/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Sêmen/efeitos dos fármacos , Sêmen/fisiologia , Tribulus/química , Adulto , Di-Hidrotestosterona/sangue , Humanos , Infertilidade Masculina/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise do Sêmen , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia
17.
Transplant Proc ; 48(10): 3303-3306, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27931573

RESUMO

BACKGROUND: Many attempts have been undertaken to better predict outcome after liver transplantation. The aim of this study was to identify the pre- and intraoperative variables that may influence the survival after liver transplantation, at a single institution. METHODS: Anesthetic records from 543 consecutive patients who underwent liver transplantation from June 2006 to June 2014 were reviewed in this retrospective study. Patients undergoing retransplantation were excluded from the analysis, as were patients with familial amyloid polyneuropathy. Preoperative variables studied were age, sex, Model for End-Stage Liver Disease score, primary diagnosis, cold ischemia time, preoperative international normalized ratio, serum albumin, and and hemoglobin levels. Intraoperative variables included were norepinephrine consumption, blood loss, red blood cell transfusion, and surgical time. Variables significant in the univariate analysis with a P value of <.2 were included in a multivariate Cox regression model. RESULTS: Only red blood cell transfusion (hazard ratio [HR], 1.16; 95% confidence interval [CI], 1.04-1.29) and female sex (HR, 1.71; 95% CI, 1.10-2.65) were identified as significant independent predictors for survival after liver transplantation. Because of proportionality assumption violation, the multivariate Cox regression model was subsequently upgraded by adding a time-varying interaction between red blood cell transfusion and time since liver transplantation. As a result, we found that at 3 months after liver transplantation, the rate of dying increased 14% (95% CI, 2%-26%) for each unit transfused, and at 6 months it increased 12% (95% CI, 0.3%-24%). CONCLUSIONS: Red blood cell transfusion ceased to influence survival from 1 year onward.


Assuntos
Transfusão de Sangue/mortalidade , Transfusão de Eritrócitos/mortalidade , Transplante de Fígado/mortalidade , Fatores de Tempo , Perda Sanguínea Cirúrgica/mortalidade , Isquemia Fria , Feminino , Hemoglobinas/análise , Humanos , Coeficiente Internacional Normatizado , Hepatopatias/cirurgia , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Período Pós-Operatório , Período Pré-Operatório , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Albumina Sérica/análise , Índice de Gravidade de Doença , Fatores Sexuais
18.
Transplant Proc ; 48(6): 2098-101, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27569952

RESUMO

BACKGROUND: Liver transplantation (LT) has been the treatment of choice to halt the progression of familial amyloid polyneuropathy (FAP). Few studies have identified prognostic factors for post-LT survival in FAP. Our aim was to assess survival rate and to identify independent factors for survival after LT. METHODS: This retrospective cohort study of FAP patients transplanted for the first time analyzed 116 transplantations from 2006 to 2014. The median follow-up period was 45.5 months. RESULTS: The overall survival rates at 1 month, 1 year, and 5 years were 89%, 82% and 79%, respectively. On multivariate analysis, only number of red blood cell (RBC) units transfused during surgery, operation time, and body mass index were independent prognostic factors for patient survival. Only 30% of patients were transfused during surgery, and, in these, each RBC unit transfused increased mortality by 53%. The operation time increased mortality by 20% for every 15 minutes of surgery. CONCLUSIONS: This study suggests that operation time and RBC transfused are predominant factors affecting post-LT survival in our FAP patients.


Assuntos
Neuropatias Amiloides Familiares/mortalidade , Transplante de Fígado/mortalidade , Adulto , Progressão da Doença , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Duração da Cirurgia , Portugal/epidemiologia , Estudos Retrospectivos , Taxa de Sobrevida
19.
J Vet Intern Med ; 30(4): 1008-13, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27214641

RESUMO

BACKGROUND: Corticosteroid treatment is commonly required in veterinary patients for treatment of inflammatory, immune-mediated, neurologic, and neoplastic diseases, which also may require assisted enteral nutrition via percutaneous endoscopic gastrostomy (PEG). OBJECTIVE: To evaluate complications associated with PEG use in dogs and cats receiving corticosteroid treatment. ANIMALS: Forty-two animals were included in the study: 12 dogs and 2 cats in the steroid group and 26 dogs and 2 cats in the control group. METHODS: Medical records, between January 2006 and March 2015, were reviewed. Patients were included if the PEG tube was in use for at least 24 hours and if complete medical records were available. Patients were assigned to the control group if they were not treated with corticosteroids during PEG use or to the steroid group if they had received corticosteroids during PEG tube use. Complications were classified as minor, moderate, and major in severity. Maximum severity complication rate was compared between groups. RESULTS: The general prevalence of complications was found to be similar between groups (P = .306), but in the steroid group, 43% of the cases developed a major severity complication compared with 18% of the control group (P = .054). CONCLUSION AND CLINICAL IMPORTANCE: Owners of dogs and cats receiving corticosteroids, in which PEG is planned, should be counseled about possible complications beyond those associated with PEG tube usage alone.


Assuntos
Corticosteroides/administração & dosagem , Doenças do Gato/cirurgia , Doenças do Cão/cirurgia , Endoscopia Gastrointestinal/veterinária , Gastrostomia/veterinária , Corticosteroides/efeitos adversos , Animais , Gatos , Cães , Endoscopia Gastrointestinal/efeitos adversos , Nutrição Enteral , Feminino , Gastrostomia/efeitos adversos , Gastrostomia/métodos , Masculino , Estudos Retrospectivos
20.
Sci Rep ; 5: 12695, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26244936

RESUMO

Superconductors, ideally diamagnetic when in the Meissner state, can also exhibit paramagnetic behavior due to trapped magnetic flux. In the absence of pinning such paramagnetic response is weak, and ceases with increasing sample thickness. Here we show that in multiband superconductors paramagnetic response can be observed even in slab geometries, and can be far larger than any previous estimate - even multiply larger than the diamagnetic Meissner response for the same applied magnetic field. We link the appearance of this giant paramagnetic response to the broad crossover between conventional Type-I and Type-II superconductors, where Abrikosov vortices interact non-monotonically and multibody effects become important, causing unique flux configurations and their locking in the presence of surfaces.

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