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1.
Br J Oral Maxillofac Surg ; 58(3): 358-360, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31864859

RESUMO

Diphtheria is an infectious disease caused by Corynebacterium diphtheriae, and is generally characterised by proliferation of the bacteria in the upper respiratory tract, formation of a pseudomembrane, and systemic diffusion of the diphtheria toxin throughout the body. We present the case of a young man with pseudomembranous plaques on the tongue and floor of the mouth, who received systemic and locoregional medical treatment, with a satisfactory outcome after 14 days.


Assuntos
Corynebacterium diphtheriae , Difteria , Humanos , Masculino , Nariz , Traqueia
3.
Proc Natl Acad Sci U S A ; 115(28): E6556-E6565, 2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29950315

RESUMO

Macrophages are key immune cells for the initiation and development of atherosclerotic lesions. However, the macrophage regulatory nodes that determine how lesions progress in response to dietary challenges are not fully understood. Liver X receptors (LXRs) are sterol-regulated transcription factors that play a central role in atherosclerosis by integrating cholesterol homeostasis and immunity. LXR pharmacological activation elicits a robust antiatherosclerotic transcriptional program in macrophages that can be affected by LXRα S196 phosphorylation in vitro. To investigate the impact of these transcriptional changes in atherosclerosis development, we have generated mice carrying a Ser-to-Ala mutation in myeloid cells in the LDL receptor (LDLR)-deficient atherosclerotic background (M-S196ALdlr-KO). M-S196ALdlr-KO mice fed a high-fat diet exhibit increased atherosclerotic plaque burden and lesions with smaller necrotic cores and thinner fibrous caps. These diet-induced phenotypic changes are consistent with a reprogramed macrophage transcriptome promoted by LXRα-S196A during atherosclerosis development. Remarkably, expression of several proliferation-promoting factors, including the protooncogene FoxM1 and its targets, is induced by LXRα-S196A. This is consistent with increased proliferation of plaque-resident cells in M-S196ALdlr-KO mice. Moreover, disrupted LXRα phosphorylation increases expression of phagocytic molecules, resulting in increased apoptotic cell removal by macrophages, explaining the reduced necrotic cores. Finally, the macrophage transcriptome promoted by LXRα-S196A under dietary perturbation is markedly distinct from that revealed by LXR ligand activation, highlighting the singularity of this posttranslational modification. Overall, our findings demonstrate that LXRα phosphorylation at S196 is an important determinant of atherosclerotic plaque development through selective changes in gene transcription that affect multiple pathways.


Assuntos
Aterosclerose/metabolismo , Proteína Forkhead Box M1/biossíntese , Regulação da Expressão Gênica , Receptores X do Fígado/metabolismo , Macrófagos/metabolismo , Mutação de Sentido Incorreto , Substituição de Aminoácidos , Animais , Aterosclerose/genética , Aterosclerose/patologia , Proliferação de Células , Proteína Forkhead Box M1/genética , Receptores X do Fígado/genética , Macrófagos/patologia , Camundongos , Camundongos Knockout , Fosforilação
4.
Metrologia ; 552018.
Artigo em Inglês | MEDLINE | ID: mdl-31080297

RESUMO

The International Committee for Weights and Measures (CIPM), at its meeting in October 2017, followed the recommendation of the Consultative Committee for Units (CCU) on the redefinition of the kilogram, ampere, kelvin and mole. For the redefinition of the kelvin, the Boltzmann constant will be fixed with the numerical value 1.380 649 × 10-23 J K-1. The relative standard uncertainty to be transferred to the thermodynamic temperature value of the triple point of water will be 3.7 × 10-7, corresponding to an uncertainty in temperature of 0.10 mK, sufficiently low for all practical purposes. With the redefinition of the kelvin, the broad research activities of the temperature community on the determination of the Boltzmann constant have been very successfully completed. In the following, a review of the determinations of the Boltzmann constant k, important for the new definition of the kelvin and performed in the last decade, is given.

5.
Rev Esp Cir Ortop Traumatol ; 61(6): 412-418, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28890123

RESUMO

OBJECTIVE: The aim of this study is to show the results of scaphotrapeziotrapezoid (STT) joint osteoarthritis treatment performing resurfacing arthroplasty with scaphoid anchorage. MATERIAL AND METHOD: An observational, descriptive and retrospective study was performed. Ten patients with isolated STT joint osteoarthritis were studied between 2013 and 2015. The mean follow-up time was 26months. Clinical results, functional and subjective scores were reviewed. RESULTS: The patients were satisfied, achieving an average of 2.1 (0-3) on the VAS score and 16 (2 to 28) in the DASH questionnaire, and returning to work in the first three months post-surgery. Recovery of range of motion compared to the contralateral wrist was 96% in extension, 95% in flexion, 87% in ulnar deviation and 91% in radial deviation. The average handgrip strength of the wrist was 95% and pinch strength was 95% compared to the contralateral side. There were no intraoperative complications or alterations in postoperative carpal alignment. CONCLUSION: Resurfacing arthroplasty is proposed as a good and novel alternative in treating isolated SST joint arthritis. Achieving the correct balance between the strength and mobility of the wrist, without causing carpal destabilisation, is important to obtain satisfactory clinical and functional results.


Assuntos
Artroplastia/métodos , Osteoartrite/cirurgia , Osso Escafoide/cirurgia , Trapezoide/cirurgia , Articulação do Punho/cirurgia , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/diagnóstico por imagem , Radiografia , Estudos Retrospectivos , Osso Escafoide/diagnóstico por imagem , Trapezoide/diagnóstico por imagem , Resultado do Tratamento , Articulação do Punho/diagnóstico por imagem
6.
J Chem Phys ; 146(24): 244309, 2017 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-28668063

RESUMO

Line intensities for carbon dioxide are measured with a novel spectroscopic approach, assisted by an optical frequency comb synthesizer for frequency calibration purposes. The main feature of the spectrometer consists in the exploitation of optical feedback from a V-shaped high-finesse optical resonator to effectively narrow a distributed feedback diode laser at the wavelength of 2 µm. Laser-gas interaction takes place inside an isothermal cell, which is placed on the transmission from the cavity. High quality, self-calibrated, absorption spectra are observed in pure CO2 samples at different gas pressures, in coincidence with three lines of the R-branch of the ν1 + 2ν2 + ν3 band. Line intensities are determined using a global fitting approach in which a manifold of spectra are simultaneously analyzed across the range of pressures between 5 and 100 Torr, sharing a restricted number of unknown parameters. Various sources of uncertainty have been identified and carefully quantified, thus leading to an overall uncertainty ranging between 0.17% and 0.23%. The measured values are in a very good agreement with recent ab initio predictions.

8.
Am J Alzheimers Dis Other Demen ; 31(3): 257-62, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26395024

RESUMO

Gait disturbance results in an increase in the risk of falls in patients with Alzheimer's disease (AD). The falls are events that might be related to an increase in the number of fractures, loss of mobility, being bedridden, early institutionalization, and increased use of medication. Therefore, the reduction in the number of falls is important for the maintenance of the functional independence of the patients as well as for the prevention of sequelae resulting from those events. Alterations in the gait occur very frequently in AD, and the gait disturbance occurs relatively early in the course of the disease. This study has important implications for public health and clinical practice. This study and previous studies have reported that abnormal gait predicts greater risk of falls, dementia, institutionalization, and death. The high prevalence and incidence of abnormal gait and its association with multiple adverse outcomes in older adults require urgent attention. Our results allow us to identify the risk factors.


Assuntos
Doença de Alzheimer/complicações , Transtornos Neurológicos da Marcha/etiologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Índice de Gravidade de Doença
9.
Vox Sang ; 109(4): 343-52, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25981525

RESUMO

BACKGROUND AND OBJECTIVES: A photochemical treatment process (PCT) utilizing amotosalen and UVA light (INTERCEPT(™) Blood System) has been developed for inactivation of viruses, bacteria, parasites and leucocytes that can contaminate blood components intended for transfusion. The objective of this study was to further characterize the safety profile of INTERCEPT-treated platelet components (PCT-PLT) administered across a broad patient population. MATERIALS AND METHODS: This open-label, observational haemovigilance programme of PCT-PLT transfusions was conducted in 21 centres in 11 countries. All transfusions were monitored for adverse events within 24 h post-transfusion and for serious adverse events (SAEs) up to 7 days post-transfusion. All adverse events were assessed for severity (Grade 0-4), and causal relationship to PCT-PLT transfusion. RESULTS: Over the course of 7 years in the study centres, 4067 patients received 19,175 PCT-PLT transfusions. Adverse events were infrequent, and most were of Grade 1 severity. On a per-transfusion basis, 123 (0.6%) were classified an acute transfusion reaction (ATR) defined as an adverse event related to the transfusion. Among these ATRs, the most common were chills (77, 0.4%) and urticaria (41, 0.2%). Fourteen SAEs were reported, of which 2 were attributed to platelet transfusion (<0.1%). No case of transfusion-related acute lung injury, transfusion-associated graft-versus-host disease, transfusion-transmitted infection or death was attributed to the transfusion of PCT-PLT. CONCLUSION: This longitudinal haemovigilance safety programme to monitor PCT-PLT transfusions demonstrated a low rate of ATRs, and a safety profile consistent with that previously reported for conventional platelet components.


Assuntos
Segurança do Sangue/métodos , Furocumarinas/efeitos adversos , Fármacos Fotossensibilizantes/efeitos adversos , Transfusão de Plaquetas/efeitos adversos , Raios Ultravioleta/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Plaquetas/efeitos dos fármacos , Plaquetas/efeitos da radiação , Segurança do Sangue/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Transfusão de Plaquetas/estatística & dados numéricos , Estudos Prospectivos
10.
Opt Express ; 23(2): 1757-66, 2015 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-25835931

RESUMO

Frequency fluctuations of an optical frequency standard at 1.39 µm have been measured by means of a highly-sensitive optical frequency discriminator based on the fringe-side transmission of a high finesse optical resonator. Built on a Zerodur spacer, the optical resonator exhibits a finesse of 5500 and a cavity-mode width of about 120 kHz. The optical frequency standard consists of an extended-cavity diode laser that is tightly stabilized against the center of a sub-Doppler H(2) (18)O line, this latter being detected by means of noise-immune cavity-enhanced optical heterodyne molecular spectroscopy. The emission linewidth has been carefully determined from the frequency-noise power spectral density by using a rather simple approximation, known as ß-line approach, as well as the exact method based on the autocorrelation function of the laser light field. It turns out that the linewidth of the optical frequency standard amounts to about 7 kHz (full width at half maximum) for an observation time of 1 ms. Compared to the free-running laser, the measured width corresponds to a line narrowing by a factor of ~220.

11.
Phys Rev Lett ; 111(6): 060803, 2013 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-23971548

RESUMO

We report on a new implementation of Doppler broadening thermometry based on precision absorption spectroscopy by means of a pair of offset-frequency locked extended-cavity diode lasers at 1.39 µm. The method consists in the highly accurate observation of the shape of the 4(4,1)→4(4,0) line of the H2(18)O ν1+ν3 band, in a water vapor sample at thermodynamic equilibrium. A sophisticated and extremely refined spectral analysis procedure is adopted for the retrieval of the Doppler width as a function of the gas pressure, taking into account the Dicke narrowing effect, the speed dependence of relaxation rates, and the physical correlation between velocity-changing and dephasing collisions. A spectroscopic determination of the Boltzmann constant with a combined (type A and type B) uncertainty of 24 parts over 10(6) is reported. This is the best result obtained so far by means of an optical method. Our determination is in agreement with the recommended CODATA value.

12.
J Chem Phys ; 138(3): 034302, 2013 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-23343271

RESUMO

Complementary tests of the partially correlated speed-dependent Keilson-Storer (pCSDKS) model for the shape of isolated transition of pure water vapor [N. H. Ngo et al., J. Chem. Phys. 136, 154310 (2012)] are made using new measurements. The latter have been recorded using a high sensitivity cavity ring down spectrometer, for seven self-broadened H(2)O lines in the 1.6 µm region at room temperature and for pressures from 0.5 to 15 Torr. Furthermore, the H(2) (18)O spectra of [M. D. De Vizia et al., Phys. Rev. A 83, 052506 (2011)] in the 1.38 µm region, measured at 273.15 K and for pressures from 0.3 to 3.75 Torr have also been used for comparison with the model. Recall that the pCSDKS model takes into account the collision-induced velocity changes, the speed dependences of the broadening and shifting coefficients as well as the partial correlation between velocity and rotational-state changes. All parameters of the model have been fixed at values previously determined, except for a scaling factor applied to the input speed-dependent line broadening. Comparisons between predictions and experiments have been made by looking at the results obtained when fitting the calculated and measured spectra by Voigt profiles. The good agreement obtained for all considered lines, at different temperature and pressure conditions, confirms the consistency and the robustness of the model. Limiting cases of the model have been then derived, showing the influence of different contributions to the line shape.


Assuntos
Simulação de Dinâmica Molecular , Água/química , Pressão , Vapor , Temperatura
13.
J Bone Joint Surg Br ; 94(7): 941-5, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22733950

RESUMO

We present the electromyographic (EMG) results ten years after open decompression of the median nerve at the wrist and compare them with the clinical and functional outcomes as judged by Levine's Questionnaire. This retrospective study evaluated 115 patients who had undergone carpal tunnel decompression at a mean of 10.47 years (9.24 to 11.36) previously. A positive EMG diagnosis was found in 77 patients (67%), including those who were asymptomatic at ten years. It is necessary to include both clinical and functional results as well as electromyographic testing in the long-term evaluation of patients who have undergone carpal tunnel decompression particularly in those in whom revision surgery is being considered. In doubtful cases or when there are differing outcomes, self-administered scales such as Levine's Questionnaire should prevail over EMG results when deciding on the need for revision surgery.


Assuntos
Síndrome do Túnel Carpal/cirurgia , Descompressão Cirúrgica/métodos , Nervo Mediano/cirurgia , Adulto , Síndrome do Túnel Carpal/diagnóstico , Eletromiografia/métodos , Feminino , Seguimentos , Humanos , Masculino , Nervo Mediano/fisiopatologia , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Satisfação do Paciente , Recuperação de Função Fisiológica/fisiologia , Recidiva , Reoperação , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
14.
J Phys Chem A ; 116(11): 2704-12, 2012 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-22103857

RESUMO

One-photon single ionization of molecules has been at the focus of several discussions concerning the reconstruction of observables obtained with ultrashort pulses from those obtained from continuous wave radiation (and vice versa). A related controversy on the conditions and observables that allow for coherent control in one-photon processes has been recently revisited (Science 2006, 313, 1257; J. Chem. Phys. 2010, 133, 151101). Our benchmark to investigate these issues is photoionization of the hydrogen molecule, where the autoionization events are the time-dependent processes in field-free evolution that could serve as a target for coherent control. We show that the variation of one-photon ionization probabilities with pulse duration are solely due to spectral effects and thus cannot be coherently controlled. We then discuss for which observables and under which conditions phase control of autoionization dynamics is possible.

15.
Opt Express ; 19(18): 17520-7, 2011 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-21935118

RESUMO

This work presents a very simple yet effective way to obtain direct referencing of a quantum-cascade-laser at 4.3 µm to a near-IR frequency-comb. Precise tuning of the comb repetition-rate allows the quantum-cascade-laser to be scanned across absorption lines of a CO2 gaseous sample and line profiles to be acquired with extreme reproducibility and accuracy. By averaging over 50 acquisitions, line-centre frequencies are retrieved with an uncertainty of 30 kHz in a linear interaction regime. The extension of this methodology to other lines and molecules, by the use of widely tunable extended-cavity quantum-cascade-lasers, paves the way to a wide availability of high-quality and traceable spectroscopic data in the most crucial region for molecular detection and interrogation.

16.
Phys Rev Lett ; 104(8): 083904, 2010 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-20366933

RESUMO

A comprehensive investigation of the frequency-noise spectral density of a free-running midinfrared quantum-cascade laser is presented for the first time. It provides direct evidence of the leveling of this noise down to a white-noise plateau, corresponding to an intrinsic linewidth of a few hundred hertz. The experiment is in agreement with the most recent theory on the fundamental mechanism of line broadening in quantum-cascade lasers, which provides a new insight into the Schawlow-Townes formula and predicts a narrowing beyond the limit set by the radiative lifetime of the upper level.

17.
Opt Express ; 16(15): 11637-46, 2008 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-18648485

RESUMO

The frequency of a DFB quantum cascade laser (QCL) emitting at 4.3 microm has been long-term stabilized to the Lamb-dip center of a CO2 ro-vibrational transition by means of first-derivative locking to the saturated absorption signal. Thanks to the non-linear sum-frequency generation (SFG) process with a fiber-amplified Nd:YAG laser, the QCL mid-infrared (IR) radiation has been linked to an optical frequency-comb synthesizer (OFCS) and its absolute frequency counted with a kHz-level precision and an overall uncertainty of 75 kHz.


Assuntos
Desenho Assistido por Computador , Lasers , Modelos Teóricos , Processamento de Sinais Assistido por Computador/instrumentação , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Raios Infravermelhos , Luz , Espalhamento de Radiação
18.
Phys Rev Lett ; 100(20): 200801, 2008 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-18518520

RESUMO

We report on a new optical implementation of primary gas thermometry based on laser-absorption spectrometry in the near infrared. The method consists in retrieving the Doppler broadening from highly accurate observations of the line shape of the R(12) nu1+2nu2(0)+nu3 transition in CO2 gas at thermodynamic equilibrium. Doppler width measurements as a function of gas temperature, ranging between the triple point of water and the gallium melting point, allowed for a spectroscopic determination of the Boltzmann constant with a relative accuracy of approximately 1.6 x 10(-4).

19.
Opt Lett ; 31(20): 3040-2, 2006 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17001393

RESUMO

We report the application of a cw distributed feedback quantum cascade laser to Lamb-dip spectroscopy of CO2 at 4.3 microm. With the laser operating in the free-running mode, we observed the sub-Doppler profile of the P(28) line of the (0,1(1),0)->(0,1(1),1) hot band by implementing a pump-probe scheme and using wavelength modulation spectroscopy for highly sensitive detection of saturated absorption signals. We investigated the main limitations to the observation of a narrow resonance, with particular attention to the effect of the laser current noise. We determined the intrinsic laser emission width, which was found to be approximately 3.4 MHz (FWHM) for an observation time of approximately 200 ms.

20.
Actas Urol Esp ; 29(8): 797-800, 2005 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-16304915

RESUMO

We present an alternative treatment of the intraepithelial neoplasms of penis (Bowen's disease), the topical application of imiquimod 5% cream. It was applied 3 times weekly for 5 weeks. Imiquimod is an imidazoquinolone immune response modifier that has been shown to have indirect antiviral and antitumor effects with few adverse effects. Imiquimod 5% cream may represent an alternative treatment option for Bowen's disease.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Aminoquinolinas/administração & dosagem , Doença de Bowen/tratamento farmacológico , Neoplasias Penianas/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Administração Tópica , Idoso , Doença de Bowen/patologia , Humanos , Imiquimode , Masculino , Neoplasias Penianas/patologia , Neoplasias Cutâneas/patologia , Resultado do Tratamento
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