Cavilha cefalomedular antirrotativa versus placa e parafuso dinâmico no tratamento de fraturas trocantéricas instáveis da anca.

As fraturas da extremidade superior do fémur, nomeadamente as fraturas trocantéricas, continuam a representar um sério problema de saúde pública em idosos com osteoporose, presentando um elevado índice de morbilidade e mortalidade, apesar dos avanços registados tanto na sua prevenção como no seu tratamento. Apenas o tratamento cirúrgico pode permitir uma marcha e uma recuperação funcional precoces, por forma que o doente consiga uma autonomia próxima da anterior à lesão. Para isso, o ortopedista dispõe atualmente de um leque alargado de implantes cirúrgicos que não tem, todavia, o mesmo valor e indicações, estando na dependência da “personalidade da fratura”. O objetivo central deste trabalho foi determinar, através de um estudo comparativo, os resultados radiológicos, clínicos e ortopédicos de uma série de 116 fraturas trocantéricas instáveis do fémur (AO 31 A2), em que se utilizaram dois tipos diferentes de implantes, a cavilha cefaloendomedular antirrotativa (PFNA®) e placa e parafuso dinâmico (DHS®). Foram analisados os registos clínicos de 116 doentes com fraturas trocantéricas instáveis, com um tempo de recuo igual ou superior a 12 meses. 66 casos foram tratados com DHS® e os restantes 50 com PFNA®. Procedeu-se ao registo do tempo operatório, do tempo de internamento, do tipo e qualidade da redução da fratura, do tempo de consolidação da fratura, da necessidade de transfusão sanguínea e das complicações clínicas e ortopédicas. Os dados obtidos foram sujeitos a um estudo estatístico usando o programa SPSS - Statistical Package for Social Sciences, versão 22.0 para Windows. Considerando a totalidade das fraturas 31 A2, o DHS® apresentou taxas superiores de reduções das fraturas consideradas insatisfatórias (23,4% e 18,0% para DHS® e PFNA®, respetivamente) e de complicações clínicas (34,8% e 32,0% para DHS® e PFNA®, respetivamente) e ortopédicas (15,2% e 14,0% para DHS® e PFNA®, respetivamente). O tempo de cirurgia, a necessidade de transfusão sanguínea (53,0% e 68,0% para DHS® e PFNA®, respectivamente) e a proporção de reduções das fraturas consideradas anatómicas (21,9% e 36,0% para DHS® e PFNA®, respectivamente) foi superior no grupo do PFNA®. O tempo de internamento e as taxas de consolidação foram semelhantes nos dois tipos de implante. Restringindo a análise apenas para o tipo específico de fraturas 31 A2.2., alguns resultados estatísticos sofreram alterações. As taxas de complicações clínicas (20,7% e 14,3% para DHS® e PFNA®, respectivamente) e ortopédicas (37,9% e 31,0% para DHS® e PFNA®, respetivamente) acentuaram-se no grupo do DHS®, com taxas de transfusão (69,0% e 64,3% para DHS® e PFNA®,respetivamente) semelhantes em ambos os grupos. No tratamento das fraturas trocantéricas instáveis da anca (31 A2.2) o PFNA® mostrou ser superior ao DHS®, em termos da qualidade de redução da fratura e nas taxas de complicações clínicas e ortopédicas. Nas estantes variáveis, o PFNA® não mostrou resultados inferiores

An Analysis of the Decay B→D∗XℓνˉℓB \rightarrow D^* X \ell \bar\nu_\ell with Predictions from Heavy Quark and Chiral Symmetry

This paper considers the implications of the heavy quark and chiral symmetries for the semi-leptonic decay $B \rightarrow D^* X \ell \bar \nu_\ell$. The general kinematic analysis for decays of the form {\sl pseudoscalar meson $\rightarrow$ vector meson $+$ pseudoscalar meson $+$ lepton $+$ anti-lepton} is presented. This formalism is applied to the above exclusive decay which allows the differential decay rate to be expressed in a form that is ideally suited for the experimental determination of the different form factors for the process through angular distribution measurements. Heavy quark and chiral symmetry predictions for the form factors are presented, and the differential decay rate is calculated in the kinematic region where chiral perturbation theory is valid.Comment: 15 pages, uses jytex.tex and tables.tex; 3 figures not included but available on reques

Note on Gauge Theory on Fuzzy Supersphere

We construct a supermatrix model whose classical background gives two-dimensional noncommutative supersphere. Quantum fluctuations around it give the supersymmetric gauge theories on the fuzzy supersphere constructed by Klimcik. This model has a parameter $\beta$ which can tune masses of the particles in the model and interpolate various supersymmetric gauge theories on sphere.Comment: 13 pages, LaTe

The effect of using rest periods in 4PB tests on the fatigue life of grouted macadams

Four-point bending tests are commonly used to assess the fatigue resistance of bi-tuminous bound materials that are used in road pavements. However, it is difficult to establish a reliable relationship between the laboratory test results and the field performance of the mate-rial. In order to predict the real life of the pavement, shift factors are normally used to convert the fatigue results obtained in the laboratory onto the actual fatigue life of the material in the field. Those shift factors depend on the type of test used, the testing conditions and the type of mixture used. In this study, an attempt was made to establish a shift factor for grouted mac-adams, based on four-point bending fatigue test results carried out with rest periods between the loading cycles. The result obtained was used to define a fatigue criterion for pavement design with grouted macadams

Classical Many-particle Clusters in Two Dimensions

We report on a study of a classical, finite system of confined particles in two dimensions with a two-body repulsive interaction. We first develop a simple analytical method to obtain equilibrium configurations and energies for few particles. When the confinement is harmonic, we prove that the first transition from a single shell occurs when the number of particles changes from five to six. The shell structure in the case of an arbitrary number of particles is shown to be independent of the strength of the interaction but dependent only on its functional form. It is also independent of the magnetic field strength when included. We further study the effect of the functional form of the confinement potential on the shell structure. Finally we report some interesting results when a three-body interaction is included, albeit in a particular model.Comment: Minor corrections, a few references added. To appear in J. Phys: Condensed Matte

Polyphenol metabolite pyrogallol-o-sulfate decreases microglial activation and vegf in retinal pigment epithelium cells and diabetic mouse retina

Funding Information: The authors acknowledge Fundacao para a Ciencia e Tecnologia for funding (PD/BD/114251/2016 scholarship to D.F. Santos; EXPL-BIM-MEC-1433-2013; PTDC/BTM/ORG/28121/2017 grants to G.A.Silva) and iNOVA4Health ? UIDB/Multi/04462/2020, a program financially supported by Funda??o para a Ci?ncia e Tecnologia/Ministerio da Educacao e Ciencia through national funds and co-funded by FEDER under the PT2020 Partnership Agreement, is also acknowledged. C.N.S. also acknowledges the European Research Council (ERC) under the European Union?s Horizon 2020 Research and Innovation Programme under Grant Agreement No. 804229. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.(Poly)phenol-derived metabolites are small molecules resulting from (poly)phenol metab-olization after ingestion that can be found in circulation. In the last decade, studies on the impact of (poly)phenol properties in health and cellular metabolism accumulated evidence that (poly)phenols are beneficial against human diseases. Diabetic retinopathy (DR) is characterized by inflammation and neovascularization and targeting these is of therapeutic interest. We aimed to study the effect of pyrogallol-O-sulfate (Pyr-s) metabolite in the expression of proteins involved in retinal glial acti-vation, neovascularization, and glucose transport. The expression of PEDF, VEGF, and GLUT-1 were analyzed upon pyrogallol-O-sulfate treatment in RPE cells under high glucose and hypoxia. To test its effect on a diabetic mouse model, Ins2Akita mice were subjected to a single intraocular injection of the metabolite and the expression of PEDF, VEGF, GLUT-1, Iba1, or GFAP measured in the neural retina and/or retinal pigment epithelium (RPE), two weeks after treatment. We observed a significant decrease in the expression of pro-angiogenic VEGF in RPE cells. Moreover, pyrogallol-O-sulfate significantly decreased the expression of microglial marker Iba1 in the diabetic retina at different stages of disease progression. These results highlight the potential pyrogallol-O-sulfate metabolite as a preventive approach towards DR progression, targeting molecules involved in both inflammation and neovascularization.publishersversionpublishe

Geometric factors in the Bohr--Rosenfeld analysis of the measurability of the electromagnetic field

The Geometric factors in the field commutators and spring constants of the measurement devices in the famous analysis of the measurability of the electromagnetic field by Bohr and Rosenfeld are calculated using a Fourier--Bessel method for the evaluation of folding integrals, which enables one to obtain the general geometric factors as a Fourier--Bessel series. When the space region over which the factors are defined are spherical, the Fourier--Bessel series terms are given by elementary functions, and using the standard Fourier-integral method of calculating folding integrals, the geometric factors can be evaluated in terms of manageable closed-form expressions.Comment: 21 pages, REVTe

The electromagnetic effects in Ke4K_{e4} decay

The final state interaction of pions in $K_{e4}$ decay allows one to obtain the value of the isospin and angular momentum zero $\pi\pi$ scattering length $a_0^0$.We take into account the electromagnetic interaction of pions and isospin symmetry breaking effects caused by different masses of neutral and charged pions and estimate the impact of these effects on the procedure of scattering length extraction from $K_{e4}$ decay.Comment: 8 pages,1 figur

The "K-Correction" for Irradiated Emission Lines in LMXBs: Evidence for a Massive Neutron Star in X1822-371 (V691 CrA)

We study the K-correction for the case of emission lines formed in the X-ray illuminated atmosphere of a Roche lobe filling star. We compute the K-correction as function of the mass ratio 'q' and the disc flaring angle 'alpha' using a compact binary code where the companion's Roche lobe is divided into 10^5 resolution elements. We also study the effect of the inclination angle in the results. We apply our model to the case of the neutron star low-mass X-ray binary X1822-371 (V691 CrA), where a K-emission velocity K_em=300 +-8 km/s has been measured by Casares et al. (2003). Our numerical results, combined with previous determination of system parameters, yields 1.61Msun < M_NS < 2.32Msun and 0.44Msun < M_2 < 0.56Msun for the two binary components(i. e. 0.24 < q < 0.27), which provide a compelling evidence for a massive neutron star in this system. We also discuss the implications of these masses into the evolutionary history of the binary.Comment: 6 pages, 5 figures. Accepted for publication in Ap