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1.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557886

RESUMO

JET's frequency-modulated continuous wave (FMCW) reflectometers have been operating well with the current design since 2005, and density profiles have been automatically calculated intershot since then. However, the calculated profiles had long suffered from several shortcomings: poor agreement with other diagnostics, sometimes inappropriately moving radially by several centimeters, elevated levels of radial jitter, and persistent wriggles (strong unphysical oscillations). In this research, several techniques are applied to the reflectometry data analysis, and the shortcomings are significantly improved. Starting with improving the equilibrium reconstruction that estimates the background magnetic field, adding a ripple correction in the reconstructed magnetic field profile, and adding new inner-wall reflection positions estimated through ray-tracing, these changes not only improve the agreement of reconstructed profiles to other diagnostics but also solve density profile wriggles that were present during band transitions. Other smaller but also persistent wriggles were also suppressed by applying a localized correction to the measured beat frequency where persistent oscillations are present. Finally, the burst analysis method, as introduced by Varela et al. [Nucl. Fusion 46 S693 (2006)], has been implemented to extract the beat frequency from stacked spectrograms. Due to the strong suppression of spurious reflections, the radial jitter that sometimes would span several centimeters has been strongly reduced. The stacking of spectrograms has also been shown to be very useful for stacking recurring events, like small gas puff modulations, and extracting transport coefficients that would otherwise be below the noise level.

2.
Mol Cell Biochem ; 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427166

RESUMO

The Yes-associated protein (YAP) oncoprotein has been linked to both metastases and resistance to targeted therapy of lung cancer cells. We aimed to investigate the effect of YAP pharmacological inhibition, using YAP/TEA domain (TEAD) transcription factor interaction inhibitors in chemo-resistant lung cancer cells. YAP subcellular localization, as a readout for YAP activation, cell migration, and TEAD transcription factor functional transcriptional activity were investigated in cancer cell lines with up-regulated YAP, with and without YAP/TEAD interaction inhibitors. Parental (A549) and paclitaxel-resistant (A549R) cell transcriptomes were analyzed. The half-maximal inhibitory concentration (IC50) of paclitaxel or trametinib, which are Mitogen-Activated protein kinase and Erk Kinase (MEK) inhibitors, combined with a YAP/TEAD inhibitor (IV#6), was determined. A three-dimensional (3D) microfluidic culture device enabled us to study the effect of IV#6/paclitaxel combination on cancer cells isolated from fresh resected lung cancer samples. YAP activity was significantly higher in paclitaxel-resistant cell lines. The YAP/TEAD inhibitor induced a decreased YAP activity in A549, PC9, and H2052 cells, with reduced YAP nuclear staining. Wound healing assays upon YAP inhibition revealed impaired cell motility of lung cancer A549 and mesothelioma H2052 cells. Combining YAP pharmacological inhibition with trametinib in K-Ras mutated A549 cells recapitulated synthetic lethality, thereby sensitizing these cells to MEK inhibition. The YAP/TEAD inhibitor lowered the IC50 of paclitaxel in A549R cells. Differential transcriptomic analysis of parental and A549R cells revealed an increased YAP/TEAD transcriptomic signature in resistant cells, downregulated upon YAP inhibition. The YAP/TEAD inhibitor restored paclitaxel sensitivity of A549R cells cultured in a 3D microfluidic system, with lung cancer cells from a fresh tumor efficiently killed by YAP/TEAD inhibitor/paclitaxel doublet. Evidence of the YAP/TEAD transcriptional program's role in chemotherapy resistance paves the way for YAP therapeutic targeting.

3.
Phys Rev Lett ; 132(2): 021001, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38277596

RESUMO

We show, for the first time, radio measurements of the depth of shower maximum (X_{max}) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre Auger Observatory we show full compatibility between our radio and the previously published fluorescence dataset, and between a subset of air showers observed simultaneously with both radio and fluorescence techniques, a measurement setup unique to the Pierre Auger Observatory. Furthermore, we show radio X_{max} resolution as a function of energy and demonstrate the ability to make competitive high-resolution X_{max} measurements with even a sparse radio array. With this, we show that the radio technique is capable of cosmic-ray mass composition studies, both at Auger and at other experiments.

4.
Phys Chem Chem Phys ; 25(29): 19899-19910, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37458414

RESUMO

This work reports a thorough molecular dynamics investigation on the aggregation patterns of curcumin and piperine in water, ethanol and a mixture of both solvents. The low solubility of curcumin in water results in a rapid formation of very stable dimers for both keto and enol tautomers. In agreement with a higher solubility, piperine molecules move closer and farther apart several times during the simulation, which indicates the formation of a less stable dimer in water. In contrast, both curcumin and piperine are soluble in ethanol and, thus, dimers can hardly be formed in this media. In comparison with a pure-water solvent, a 30 : 70 mixture of ethanol and water significantly reduces the probability of formation of most dimers of curcumin and piperine molecules. The simulations show that larger clusters may be complex structures, but the formation of stacks (in the case of piperine and enol tautomer of curcumin) and cages (when the keto tautomer of curcumin is involved) are not rare. Furthermore, it is shown that each single molecule presents a certain degree of mobility in the cluster, especially on the surface, but without leading to dissociation.

5.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 42(3): 147-155, mayo - jun. 2023. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-219923

RESUMO

Objetivo principal: comparar la efectividad para la comprobación de márgenes quirúrgicos entre SPECT portátil y la mamografía de la pieza (RxM). Objetivo secundario: estandarizar un protocolo preintraquirúrgico mediante SPECT portátil y evaluar el tiempo requerido en el uso de esta técnica. Material y métodos Estudio longitudinal prospectivo con 36 pacientes (39 lesiones) diagnosticadas de cáncer de mama con criterios para realización SNOLL/ROLL. Se realiza en estudio prequirúrgico de la lesión tumoral, tras la administración ecoguiada de [99mTc]Tc-nanocoloides de albúmina/[99mTc]Tc-macroagregados de albúmina, en la lesión tumoral. Mediante SPECT portátil se obtienen imágenes híbridas (óptico + SPECT) e imágenes de navegación en 3D con sonda gamma. En quirófano se obtienen 4-5 imágenes con SPECT portátil, I) sobre piel para localización tumoral II) tras exposición de lecho para guía de resección, III) del lecho tras exéresis, IV y V) a la pieza quirúrgica. Se decide ampliación o no de márgenes considerando tres criterios: a) actividad residual (cps) en bordes de resección del lecho; b) análisis visual de la captación en la pieza; c) una distancia mínima de 10mm de los bordes de la pieza hasta el centro de mayor captación, más el radio de la lesión. En este estudio se valora la concordancia de: la medición de la profundidad entre ecografía y SPECT portátil en el estudio prequirúrgico; los márgenes quirúrgicos entre SPECT portátil vs. RxM, teniendo de técnica de referencia anatomía patológica (AP); del tiempo quirúrgico empleado con SPECT portátil (AU)


Objectives Main objective: To compare the effectiveness for checking surgical margins between SPECT-portable and mammography of the piece (RxM). Secondary objective: To standardize a pre-operative protocol using SPECT-portable and to evaluate the time required in the use of this technique. Material and method Prospective longitudinal study with 36 patients (39 lesions) diagnosed with breast cancer (CM) with criteria for SNOLL/ROLL. A pre-surgical study of the tumor lesion was performed, after the eco-guided administration of 99mTc-nanocolloids of albumin/99mTc-macroaggregates of albumin, in the tumor lesion. Hybrid images (optical+SPECT) and 3D navigation images with gamma probe are obtained using freehandSPECT. In the operating room, 4–5 images are obtained with freehandSPECT, (I) on skin for tumor location, (II) after exposure of surgical bed for resection guide, (III) of the surgical bed after exeresis, (IV and V) the anterior–posterior and lateral surface of the surgical specimen. The three criteria to decide to extend the margins are: (a) residual activity (cps) at the edges of the surgical bed resection; (b) visual analysis of the uptake in the specimen; (c) a minimum distance of 10mm from the edges of the specimen to the center of greatest uptake, plus the radius of the lesion. We study the concordance of: the depth measurement between ultrasound and freehandSPECT; the surgical margins between freehandSPECT vs. mammography of the specimen (RxM), considering anatomical pathology (AP) as the gold standard technique as reference; surgical time used with freehandSPECT and RxM. Results Intraoperative localization was performed in all cases. False negative (FN: no detection margin affected) with freehandSPECT: 9 margins; with RxM: 8 (AU)


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Margens de Excisão , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Estadiamento de Neoplasias , Sensibilidade e Especificidade , Estudos Longitudinais , Estudos Prospectivos
6.
Phys Rev Lett ; 130(6): 061001, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36827568

RESUMO

Instantons, which are nonperturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give rise to decays of particles otherwise forbidden. Using data collected at the Pierre Auger Observatory, we search for signatures of such instanton-induced processes that would be suggestive of super-heavy particles decaying in the Galactic halo. These particles could have been produced during the post-inflationary epoch and match the relic abundance of dark matter inferred today. The nonobservation of the signatures searched for allows us to derive a bound on the reduced coupling constant of gauge interactions in the dark sector: α_{X}≲0.09, for 10^{9}≲M_{X}/GeV<10^{19}. Conversely, we obtain that, for instance, a reduced coupling constant α_{X}=0.09 excludes masses M_{X}≳3×10^{13} GeV. In the context of dark matter production from gravitational interactions alone, we illustrate how these bounds are complementary to those obtained on the Hubble rate at the end of inflation from the nonobservation of tensor modes in the cosmological microwave background.

7.
Artigo em Inglês | MEDLINE | ID: mdl-36403725

RESUMO

OBJECTIVES: Main objective: To compare the effectiveness for checking surgical margins between SPECT-portable and mammography of the piece (RxM). SECONDARY OBJECTIVE: To standardize a pre-operative protocol using SPECT-portable and to evaluate the time required in the use of this technique. MATERIAL AND METHODS: Prospective longitudinal study with 36 patients (39 lesions) diagnosed with breast cancer (CM) with criteria for SNOLL/ROLL. A pre-surgical study of the tumor lesion was performed, after the eco-guided administration of 99mTc-nanocolloids of albumin/99mTc-macroaggregates of albumin, in the tumor lesion. Hybrid images (optical + SPECT) and 3D navigation images with gamma probe are obtained using freehandSPECT. In the operating room, 4-5 images are obtained with freehandSPECT, (I) on skin for tumor location, (II) after exposure of surgical bed for resection guide, (III) of the surgical bed after exeresis, (IV and V) the anterior-posterior and lateral surface of the surgical specimen. The three criteria to decide to extend the margins are: (a) residual activity (cps) at the edges of the surgical bed resection; (b) visual analysis of the uptake in the specimen; (c) a minimum distance of 10 mm from the edges of the specimen to the center of greatest uptake, plus the radius of the lesion. We study the concordance of: the depth measurement between ultrasound and freehandSPECT; the surgical margins between freehandSPECT vs. mammography of the specimen (RxM), considering anatomical pathology (AP) as the gold standard technique as reference; surgical time used with freehandSPECT and RxM. RESULTS: Intraoperative localization was performed in all cases. False negative (FN: no detection margin affected) with freehandSPECT: 9 margins; with RxM: 8. True positive (TP: detection margin affected) with freehandSPECT: 5 margins, with RxM: 6. True negative (TN: consider free margin when healthy) with freehandSPECT: 213 margins; with RxM: 196. Negative predictive value (NPV: probability of negative margin on unaffected part) with freehandSPECT: 95.9%, with RxM: 96.07%. Specificity with freehandSPECT: 96.8%, with RxM: 97%. The concordance of surgical bed margins between freehandSPECT and RxM: 94.5%. Between freehandSPECT and AP: 93.1%. Between RxM and PA: 93.5%, being all statistically significant (p-value <0.000), so we can affirm that both techniques are related or dependent on the reference technique, the PA. Degree of correlation between SPECT-portable and low PA (Kappa index: 0.34, 95% CI [0.22-0.47], and between RxM and moderate PA (Kappa index: 0.42, 95% CI [0.29-0.56], p-value <0.001. Comparison of the successes and failures of both techniques (SPECT-portable and RxM) and PA: Distribution χ2: 0.023 with degree of freedom 1, with value <0.05, so we can affirm that both techniques are similar, since there are no significant statistical differences. Median total OR time: 60.25 min (30-145). Mean freehandSPECT OR time: 5 scans = 10 min. CONCLUSIONS: There are no statistically significant differences in the probability to rule out affective margins that require a second surgery between both techniques (SPECT-portable and RxM) so, the technique performed with SPECT-Portable is a useful and effective procedure, which requires specific training with an optimized and multidisciplinary protocol. The time spent with SPECT-portable is feasible for daily practice.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Margens de Excisão , Estudos Prospectivos , Estudos Longitudinais , Tomografia Computadorizada de Emissão de Fóton Único , Albuminas
8.
Ann Med Surg (Lond) ; 77: 103645, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35637985

RESUMO

Background: Curative-intent therapies for hepatocellular carcinoma (HCC) include radiofrequency ablation (RFA), liver resection (LR), and liver transplantation (LT). Controversy exists in treatment selection for early-stage tumours. We sought to evaluate the oncologic outcomes of patients who received either RFA, LR, or LT as first-line treatment for solitary HCC ≤ 3 cm in an intention-to-treat analysis. Materials and methods: All patients with solitary HCC ≤ 3 cm who underwent RFA, LR, or were listed for LT between Feb-2000 and Nov-2018 were analyzed. Cox regression analysis was then performed to compare intention-to-treat (ITT) survival by initial treatment allocation and disease-free survival (DFS) by treatment received in patients eligible for all three treatments. Results: A total of 119 patients were identified (RFA n = 83; LR n = 25; LT n = 11). The overall intention-to-treat survival was similar between the three groups. The overall DFS was highest for the LT group. This was significantly higher than RFA (p = 0.02), but not statistically significantly different from LR (p = 0.14). After multivariable adjustment, ITT survival was similar in the LR and LT groups relative to RFA (LR HR:1.13, 95%CI 0.33-3.82; p = 0.80; LT HR:1.39, 95%CI 0.35-5.44; p = 0.60). On multivariable DFS analysis, only LT was better relative to RFA (LR HR:0.52, 95%CI 0.26-1.02; p = 0.06; LT HR:0.15, 95%CI 0.03-0.67; p = 0.01). Compared to LR, LT was associated with a numerically lower hazard on multivariable DFS analysis, though this did not reach statistical significance (HR 0.30, 95%CI 0.06-1.43; p = 0.13). Conclusion: For treatment-naïve patients with solitary HCC ≤ 3 cm who are eligible for RFA, LR, and LT, adjusted ITT survival is equivalent amongst the treatment modalities, however, DFS is better with LR and LT, compared with RFA. Differences in recurrence between treatment modalities and equipoise in ITT survival provides support for a future prospective trial in this setting.

9.
Phys Rev Lett ; 126(15): 152002, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929235

RESUMO

We present the first measurement of the fluctuations in the number of muons in extensive air showers produced by ultrahigh energy cosmic rays. We find that the measured fluctuations are in good agreement with predictions from air shower simulations. This observation provides new insights into the origin of the previously reported deficit of muons in air shower simulations and constrains models of hadronic interactions at ultrahigh energies. Our measurement is compatible with the muon deficit originating from small deviations in the predictions from hadronic interaction models of particle production that accumulate as the showers develop.

10.
Phys Rev Lett ; 125(12): 121106, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-33016715

RESUMO

We report a measurement of the energy spectrum of cosmic rays above 2.5×10^{18} eV based on 215 030 events. New results are presented: at about 1.3×10^{19} eV, the spectral index changes from 2.51±0.03(stat)±0.05(syst) to 3.05±0.05(stat)±0.10(syst), evolving to 5.1±0.3(stat)±0.1(syst) beyond 5×10^{19} eV, while no significant dependence of spectral features on the declination is seen in the accessible range. These features of the spectrum can be reproduced in models with energy-dependent mass composition. The energy density in cosmic rays above 5×10^{18} eV is [5.66±0.03(stat)±1.40(syst)]×10^{53} erg Mpc^{-3}.

11.
Rev Neurol ; 68(6): 229-235, 2019 Mar 16.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-30855706

RESUMO

INTRODUCTION: There is poor knowledge on current hospitalizations in the multiple sclerosis (MS) population. The purpose of this study was to determine hospitalization causes and outcomes in a MS hospital-based cohort. PATIENTS AND METHODS: A retrospective chart review was performed on all patients admitted at our centre between August, 2009 and July, 2015, excluding those with no previous established diagnosis. RESULTS: 308 hospitalizations were included, representing a total of 155 patients (female, 67.5%). Median age at hospitalizations was 47 years, with median disease duration of 12 years. The most common overall reason for hospitalization was infectious diseases (22.1%), followed by MS relapses (12.7%) and neurogenic bladder (11%). The median length of hospitalization for all patients was 5 days and the progressive subtype of MS had longer lengths of hospitalization than the relapsing-remitting MS. Intensive care unit admission occurred in 23 cases (7.5%) and were associated with increased mortality and length of hospitalization. Of the 308 hospitalizations, 9 (2.9%) resulted in death. CONCLUSION: Infections are the most common cause of hospitalizations in our study, although MS relapses or complications related to MS continue to be significant causes of morbidity. Almost 8% of all MS hospitalizations required intensive care unit admission and these were related to longer admission lengths and higher death rates.


TITLE: Causas de hospitalizacion en pacientes con esclerosis multiple.Introduccion. Existe un escaso conocimiento actual sobre las hospitalizaciones en la poblacion con esclerosis multiple (EM). El proposito de este estudio fue determinar las causas y resultados de la hospitalizacion en una cohorte hospitalaria de pacientes con EM. Pacientes y metodos. Se realizo un estudio retrospectivo de los registros clinicos de todos los pacientes ingresados en nuestro centro entre agosto de 2009 y julio de 2015, excluyendo a los que no tenian un diagnostico previo establecido. Resultados. Se incluyeron 308 hospitalizaciones, lo que representa un total de 155 pacientes (mujeres, 67,5%). La mediana de edad en las hospitalizaciones fue de 47 años, con una duracion media de la enfermedad de 12 años. La principal razon para la hospitalizacion fueron las enfermedades infecciosas (22,1%), seguidas de los brotes (12,7%) y la vejiga neurogena (11%). La duracion media de la hospitalizacion para todos los pacientes fue de cinco dias, y el subtipo progresivo de la EM tuvo una mayor duracion de la hospitalizacion que la EM remitente recurrente. El ingreso en la unidad de cuidados intensivos ocurrio en 23 casos (7,5%), que se asociaron con mayor mortalidad y duracion de la hospitalizacion. Del total de hospitalizaciones, nueve (2,9%) acabaron en muerte. Conclusiones. Las infecciones son la causa mas frecuente de hospitalizacion, aunque las recaidas de la EM o las complicaciones relacionadas siguen siendo causas importantes de morbilidad. Casi el 8% de todas las hospitalizaciones por EM requirio ingreso en la unidad de cuidados intensivos, lo que se relaciono con una mayor duracion de la estancia y mayores tasas de mortalidad.


Assuntos
Hospitalização , Esclerose Múltipla/terapia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
12.
Int J Tuberc Lung Dis ; 23(3): 344-348, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30871666

RESUMO

SETTING: Latent tuberculous infection (LTBI) is an important reservoir of disease reactivation that is sufficient to generate new cases for decades. The tuberculin skin test (TST) is an important tool to diagnose LTBI; however, neonatal bacille Calmette-Guérin (BCG) vaccination may impact interpretation of TST data. OBJECTIVES: To analyse the effect of the neonatal BCG vaccine on TST reaction in the first 2 years of life in children with no identified contact with tuberculosis (TB). DESIGN: This was a cross-sectional study in children up to 2 years of age who received neonatal BCG vaccination. In the absence of baseline comorbidities or contact with the bacillus, the children were given the TST. RESULTS: Seventy-nine children participated in the study. A decline in TST reactivity was observed in the first 12-24 months of age in patients who had been vaccinated with neonatal BCG but with no contact with TB. After the age of 10 months, no patient showed a TST reaction of >5 mm. CONCLUSION: BCG had low impact on the TST in children with no TB contact. This finding suggests the need to reassess the cut-off point to 5 mm of induration to improve TST specificity in LTBI identification.


Assuntos
Vacina BCG/administração & dosagem , Tuberculose Latente/diagnóstico , Teste Tuberculínico/métodos , Vacina BCG/imunologia , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Tuberculose Latente/imunologia , Masculino , Sensibilidade e Especificidade
14.
Ann Cardiol Angeiol (Paris) ; 67(2): 61-66, 2018 Apr.
Artigo em Francês | MEDLINE | ID: mdl-29530274

RESUMO

OBJECTIVES: This cross-sectional epidemiological study aimed at determining the prevalence of cardiovascular risk factors (CVRF; including obesity, dyslipidaemia, hypertension, diabetes and smoking), among patients from the Algerian sub-population of the "Africa/Middle East Cardiovascular Epidemiological" study attending general practitioners at primary healthcare facilities, and stratified according to their environment (rural/urban), sex and age. PATIENTS AND METHODS: The study sites, located in 10 wilayas (administrative regions), were situated in urban and rural areas (rural populations defined as living at least 50km away from urban centres, or lacking access to suburban transport). RESULTS: Four hundred and ten subjects (262 female, 148 male) were enrolled; 287 subjects were from an urban environment and 123 from a rural environment. Mean age was 50.4 years. Ninety one point eight percent of patients had ≥1 CVRF; 48.2% had ≥3 CVRF. Prevalence for the different CVRF was: 61.7% for dyslipidaemia; 39.5% for hypertension; 25.0% for diabetes; 10.0% for smoking, 70.0% for abdominal obesity and 32.0% for a body mass index ≥30kg/m2. CONCLUSION: The high prevalence of all CVRF observed in the Algeria sub-group, especially among the rural population, should encourage us to develop a carefully planned strategy for primary prevention, opportunistic screening and early management, in both urban and rural settings, and with particular attention to young adults. These actions should involve all state bodies and those active in civil society, in order to guarantee full achievement of set goals. The ACE trial is registered under NCT01243138.


Assuntos
Doenças Cardiovasculares/epidemiologia , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adolescente , Adulto , Idoso , Argélia/epidemiologia , Índice de Massa Corporal , Doenças Cardiovasculares/etiologia , Estudos Transversais , Diabetes Mellitus/epidemiologia , Dislipidemias/complicações , Dislipidemias/epidemiologia , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Oriente Médio/epidemiologia , Obesidade/epidemiologia , Prevalência , Fatores de Risco
16.
Phys Med ; 42: 13-18, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29173906

RESUMO

PURPOSE: Optimization studies in digital mammography aid to assure the image quality and radiological protection of the patient. The aim of this work is to test effectiveness and applicability of a method based on a Figure of Merit (FOM=(IQFinv)2/AGD) to improve all the exposure parameters (Target/Filter combination, kVp and mAs) in order to improve the image acquisition technique that will provide the best compromise between image quality and the average glandular dose (AGD). METHODS: A contrast-detail analysis, employing the test object CDMAM, was carried out for the digital mammography unit manufactured by Lorad Hologic - model Selenia. We simulated two breast thicknesses using phantoms and a Figure of Merit as optimization tool, which includes an indicator of image quality, the IQFinv and the average glandular dose. Images of the ACR and TORMAM phantoms were obtained with both, automatic and optimized exposure parameters. In order to compare the image quality, the SNR (Signal to Noise Ratio) was measured in each image. RESULTS: In the two phantoms, for both 4.5 and 7.5cm thicknesses, the AGDs obtained with the optimized parameters show a reduction. In addition, the images obtained with the optimized exposure parameters, had the same or a better image quality when compared to the images obtained using the automatic mode. CONCLUSIONS: The proposed optimization methodology proved to be an effective tool to improve the digital mammography unit, due to the use of objective metrics for evaluation and validation of the results.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Mamografia/métodos , Doses de Radiação , Mama/diagnóstico por imagem , Mama/efeitos da radiação , Simulação por Computador , Humanos , Mamografia/instrumentação , Modelos Anatômicos , Reconhecimento Automatizado de Padrão/métodos , Imagens de Fantasmas , Melhoria de Qualidade , Proteção Radiológica/métodos
17.
Rev Port Pneumol (2006) ; 23(6): 343-351, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28623106

RESUMO

This review aims to appraise the role of physiotherapy care in patients submitted to pulmonary surgery, in preoperative, perioperative, and postoperative phases. Pulmonary surgery is the gold standard treatment for patients with lung cancer if it is completely resectable. However, the major impairments and complications induced by surgery are well known. Physiotherapy has been regularly used both in the preparation of the surgical candidates; in their functional recovery in the immediate postoperative period, and in the medium/long term but there is a lack of concise evidence-based recommendations. Therefore, the aim of this review is to appraise the literature about the role of physiotherapy interventions in patients undergoing lung surgery for lung cancer, in preoperative, perioperative, postoperative and maintenance stages, to the recovery and well-being, regardless of the extent of surgical approach. In conclusion, physiotherapy programs should be individually designed, and the goals established according to surgery timings, and according to each subject's needs. It can also be concluded that in the preoperative phase, the main goals are to avoid postoperative pulmonary complications and reduce the length of hospital stay, and the therapeutic targets are respiratory muscle training, bronchial hygiene and exercise training. For the perioperative period, breathing exercises for pulmonary expansion and bronchial hygiene, as well as early mobilization and deambulation, postural correction and shoulder range of motion activities, should be added. Finally, it can be concluded that in the postoperative phase exercise training should be maintained, and adoption of healthy life-style behaviours must be encouraged.


Assuntos
Neoplasias Pulmonares/cirurgia , Assistência Perioperatória , Modalidades de Fisioterapia , Pneumonectomia , Humanos
18.
Med. UIS ; 30(1): 21-33, ene.-abr. 2017. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-894189

RESUMO

RESUMEN Introducción: la diarrea aguda y la mortalidad por diarrea continúan siendo un problema de salud pública a nivel mundial, especialmente en los países de ingreso medio o bajo. Gran parte de las enfermedades diarreicas son prevenibles mediante el acceso al agua potable y a servicios adecuados de saneamiento e higiene. Objetivo: caracterizar los conocimientos, actitudes y prácticas de cuidadores de niños menores de cinco años asociados a prevalencia de diarrea. Materiales y métodos: estudio observacional analítico de corte transversal, realizado durante el periodo 2014-2015. Se realizó un muestreo por conglomerados en la comuna norte de la ciudad de Bucaramanga y se aplicó una encuesta dirigida. Resultados: solo uno de cada diez cuidadores conoce todas las características de la diarrea aguda (cambios en la consistencia, número y duración de los síntomas) y ninguno reconoce totalmente los signos de deshidratación. El uso de remedios caseros y la creencia en causas sobrenaturales y esotéricas como causas de diarrea tuvo una alta prevalencia. La menor edad del cuidador, tener aseguramiento y mayor nivel conocimientos sobre la diarrea se asociaron a un mayor reporte de episodios de diarrea en los últimos seis meses. Conclusiones: el 49% de todos los cuidadores encuestados manifestaron que sus niños han tenido al menos un episodio de diarrea en los últimos seis meses. El nivel de conocimientos de los cuidadores es bajo. Se encontró asociación estadísticamente significativa entre la edad del cuidador, conocimiento de los síntomas diarreicos, régimen de aseguramiento y prevalencia de diarrea en menores de cinco años. MÉD.UIS. 2017;30(1):21-33.


ABSTRACT Introduction: acute diarrhea and mortality from diarrhea remains a public health problem worldwide, particularly in middle-income countries or low. Much of diarrheal diseases are preventable through access to safe water and adequate sanitation and hygiene. Objective: to characterize the knowledge, attitudes and practices of caregivers of children under five years associated with prevalence of diarrhea. Materials and methods: cross-sectional observational study, made during the period 2014-2015. Cluster sampling was conducted in the northern district of the city of Bucaramanga. A targeted survey was conducted. Results: only one in ten caregivers know all the characteristics (changes in consistency, number and duration of symptoms) of acute diarrhea. None fully recognize the signs of dehydration. The use of home remedies and belief in supernatural and esoteric causes as causes of diarrhea had a high prevalence. Caregiver younger, having higher-level assurance and knowledge on diarrhea associated with increased reporting of episodes of diarrhea in the last six months. Conclusions: 49% of all respondents report that their children caregivers have had at least one episode of diarrhea in the last six months. The level of knowledge of caregivers is low. Age of the caregiver, knowledge about diarrhea symptoms and healthcare affiliation was statistically associated with the onset of diarrhea in children up to five years. MÉD.UIS. 2017;30(1):21-33.


Assuntos
Humanos , Lactente , Pré-Escolar , Diarreia , Criança , Cuidado da Criança , Conhecimentos, Atitudes e Prática em Saúde , Cuidadores
19.
Philos Trans A Math Phys Eng Sci ; 375(2092)2017 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-28320902

RESUMO

Although there is a long history behind the idea of chemical structure, this is a key concept that continues to challenge chemists. Chemical structure is fundamental to understanding most of the properties of matter and its knowledge for complex systems requires the use of state-of-the-art techniques, either experimental or theoretical. From the theoretical view point, one needs to establish the interaction potential among the atoms or molecules of the system, which contains all the information regarding the energy landscape, and employ optimization algorithms to discover the relevant stationary points. In particular, global optimization methods are of major importance to search for the low-energy structures of molecular aggregates. We review the application of global optimization techniques to several molecular clusters; some new results are also reported. Emphasis is given to evolutionary algorithms and their application in the study of the microsolvation of alkali-metal and Ca2+ ions with various types of solvents.This article is part of the themed issue 'Theoretical and computational studies of non-equilibrium and non-statistical dynamics in the gas phase, in the condensed phase and at interfaces'.

20.
HIV Med ; 18(3): 214-219, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27535019

RESUMO

OBJECTIVES: The aim of the study was to provide insights into the contributions of HIV infection stage, antiretroviral therapy (ART) and vascular risk factors to the occurrence of ischaemic stroke in HIV-infected patients. METHODS: We performed a case-control study of HIV-infected patients followed in our clinic. We compared patients hospitalized between January 2006 and June 2014 with an ischaemic stroke or transient ischaemic attack to age- and gender-matched controls without stroke. RESULTS: Of 2146 patients followed in our clinic, we included 23 cases (20 men and three women; mean age 51.3 years) and 23 controls. Eighty-three per cent of cases had had a stroke and 17% a transient ischaemic attack. According to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification, small-vessel occlusion was the most frequent aetiology, followed by large-artery atherosclerosis and cardioembolism. Compared with controls, stroke was statistically significantly associated with diabetes, smoking and low concentrations of high-density lipoprotein (HDL) cholesterol. Illegal drug use, a low CD4 count and a high viral load were also associated with ischaemic cerebral events. There were no statistically significant differences between cases and controls in Centers for Disease Control and Prevention (CDC) HIV stage, CD4 count nadir and HIV infection time-to-event. No statistically significant differences were found concerning ART or treatment compliance. CONCLUSIONS: In our single centre study, we found associations of illegal drug use, HIV replication and some traditional vascular risk factors with the occurrence of ischaemic cerebral events. The paradigm of the care of HIV-infected patients is changing. Concomitant diseases in the ageing patient with HIV infection, including cerebrovascular disease, must also be addressed in view of their impacts on morbidity and mortality. Apart from controlling the HIV infection and immunosuppression with ART, vascular risk factors must also be addressed.


Assuntos
Infecções por HIV/complicações , Acidente Vascular Cerebral/epidemiologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco
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