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2.
Healthcare (Basel) ; 12(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38338293

RESUMO

BACKGROUND: The widespread adoption of mobile devices by adolescents underscores the potential to harness these tools to instill healthy habits into their daily lives. An exemplary manifestation of this initiative is the Healthy Jeart app, crafted with the explicit goal of fostering well-being. METHODOLOGY: This study, framed within an applied investigation, adopts an exploratory and descriptive approach, specifically delving into the realm of user experience analysis. The focus of this research is a preliminary examination aimed at understanding users' perceived usability of the application. To glean insights, a comprehensive questionnaire was administered to 101 teenagers, seeking their evaluations on various usability attributes. The study took place during 2022. RESULTS: The findings reveal a considerable consensus among users regarding the evaluated usability aspects. However, the areas for improvement predominantly revolve around managing the information density, particularly for a subset of end users grappling with overwhelming content. Additionally, recommendations are put forth to streamline the confirmation process for user suggestions and comments. CONCLUSION: This analysis illuminates both the strengths of the app and areas ripe for refinement, paving the way for a more user-centric and efficacious Healthy Jeart application.

3.
Echocardiography ; 41(1): e15726, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38078698

RESUMO

BACKGROUND: Iron deficiency correction with ferric carboxymaltose improves symptoms and reduces rehospitalization in patients with reduced left ventricular ejection fraction. The mechanisms underlying these improvements are poorly understood. This study aimed to determine changes in left ventricular contractility after iron treatment as reflected in global longitudinal strain. METHODS: Prospective single-center study including 43 adults with reduced ejection fraction, non-anemic iron deficiency, and functional class II-III heart failure despite optimal medical treatment. Global longitudinal strain through speckle-tracking echocardiography was measured at baseline and 4 weeks after ferric carboxymaltose. RESULTS: A significant improvement in global longitudinal strain was detected (from -12.3% ± 4.0% at baseline to -15.6% ± 4.1%, p < .001); ferritin and transferrin saturation index had increased, but ejection fraction presented no significant changes (baseline 35.7% ± 4.6%, follow-up 37.2% ± 6.6%, p = .073). CONCLUSIONS: In patients with heart failure and reduced ejection fraction, the correction of iron deficiency with ferric carboxymaltose is associated with an early improvement in global longitudinal strain, possibly suggesting a direct effect of iron correction on myocardial contractility.


Assuntos
Anemia Ferropriva , Insuficiência Cardíaca , Deficiências de Ferro , Maltose/análogos & derivados , Disfunção Ventricular Esquerda , Adulto , Humanos , Volume Sistólico , Estudos Prospectivos , Deformação Longitudinal Global , Função Ventricular Esquerda , Compostos Férricos/uso terapêutico , Compostos Férricos/farmacologia , Ferro/farmacologia , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/diagnóstico por imagem , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico por imagem , Anemia Ferropriva/complicações , Anemia Ferropriva/tratamento farmacológico
4.
J Am Heart Assoc ; 12(18): e029251, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37721152

RESUMO

Background Establishing surgical criteria for aortic valve replacement (AVR) in severe aortic regurgitation in young adults is challenging due to the lack of evidence-based recommendations. We studied indications for AVR in young adults with severe aortic regurgitation and their outcomes, as well as the relationship between presurgical echocardiographic parameters and postoperative left ventricular (LV) size, function, clinical events, and valve-related complications. Methods and Results Data were collected retrospectively on 172 consecutive adult patients who underwent AVR or repair for severe aortic regurgitation between 2005 and 2019 in a tertiary cardiac center (age at surgery 29 [22-41] years, 81% male). One-third underwent surgery before meeting guideline indications. Postsurgery, 65% achieved LV size and function normalization. LV ejection fraction showed no significant change from baseline. A higher presurgical LV end-systolic diameter correlated with a lack of LV normalization (odds ratio per 1-cm increase 2.81, P<0.01). The baseline LV end-systolic diameter cut-off for predicting lack of LV normalization was 43 mm. Pre- and postoperative LV dimensions and postoperative LV ejection fraction predicted clinical events during follow-up. Prosthetic valve-related complications occurred in 20.3% during an average 5.6-year follow-up. Freedom from aortic reintervention was 98%, 96.5%, and 85.4% at 1, 5, and 10 years, respectively. Conclusions Young adult patients with increased baseline LV end-systolic diameter or prior cardiac surgery are less likely to achieve LV normalization after AVR. Clinicians should carefully balance the long-term benefits of AVR against procedural risks and future interventions, especially in younger patients. Evidence-based criteria for AVR in severe aortic regurgitation in young adults are crucial to improve outcomes.


Assuntos
Insuficiência da Valva Aórtica , Adulto Jovem , Humanos , Masculino , Adulto , Feminino , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/cirurgia , Estudos Retrospectivos , Coração , Aorta , Catéteres
5.
iScience ; 26(6): 106832, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37250794

RESUMO

Uncertainty persists whether anaerobic bacteria represent important pathogens in aspiration pneumonia. In a nested case-control study of mechanically ventilated patients classified as macro-aspiration pneumonia (MAsP, n = 56), non-macro-aspiration pneumonia (NonMAsP, n = 91), and uninfected controls (n = 11), we profiled upper (URT) and lower respiratory tract (LRT) microbiota with bacterial 16S rRNA gene sequencing, measured plasma host-response biomarkers, analyzed bacterial communities by diversity and oxygen requirements, and performed unsupervised clustering with Dirichlet Multinomial Models (DMM). MAsP and NonMAsP patients had indistinguishable microbiota profiles by alpha diversity and oxygen requirements with similar host-response profiles and 60-day survival. Unsupervised DMM clusters revealed distinct bacterial clusters in the URT and LRT, with low-diversity clusters enriched for facultative anaerobes and typical pathogens, associated with higher plasma levels of SPD and sCD14 and worse 60-day survival. The predictive inter-patient variability in these bacterial profiles highlights the importance of microbiome study in patient sub-phenotyping and precision medicine approaches for severe pneumonia.

6.
Crit Care Explor ; 4(5): e0699, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35620769

RESUMO

Determine the role of surfactant protein D (SPD) in sepsis. DESIGN: Murine in vivo study. SETTING: Research laboratory at an academic medical center. PATIENTS: SPD knockout (SPD-/-) and wild-type (SPD+/+) mice. INTERVENTIONS: SPD-/- and SPD+/+ mice were subjected to cecal ligation and puncture (CLP). After CLP, Escherichia coli bacteremia was assessed in both groups. Cecal contents from both groups were cultured to assess for colonization by E. coli. To control for parental effects on the microbiome, SPD-/- and SPD+/+ mice were bred from heterozygous parents, and levels of E. coli in their ceca were measured. Gut segments were harvested from mice, and SPD protein expression was measured by Western blot. SPD-/- mice were gavaged with green fluorescent protein, expressing E. coli and recombinant SPD (rSPD). MEASUREMENTS AND MAIN RESULTS: SPD-/- mice had decreased mortality and decreased E. coli bacteremia compared with SPD+/+ mice following CLP. At baseline, SPD-/- mice had decreased E. coli in their cecal flora. When SPD-/- and SPD+/+ mice were bred from heterozygous parents and then separated after weaning, less E. coli was cultured from the ceca of SPD-/- mice. E. coli gut colonization was increased by gavage of rSPD in SPD-/- mice. The source of enteric SPD in SPD+/+ mice was the gallbladder. CONCLUSIONS: Enteral SPD exacerbates mortality after CLP by facilitating colonization of the mouse gut with E. coli.

7.
JCI Insight ; 6(14)2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34138757

RESUMO

The acute respiratory distress syndrome (ARDS) is a highly lethal condition that impairs lung function and causes respiratory failure. Mechanical ventilation (MV) maintains gas exchange in patients with ARDS but exposes lung cells to physical forces that exacerbate injury. Our data demonstrate that mTOR complex 1 (mTORC1) is a mechanosensor in lung epithelial cells and that activation of this pathway during MV impairs lung function. We found that mTORC1 is activated in lung epithelial cells following volutrauma and atelectrauma in mice and humanized in vitro models of the lung microenvironment. mTORC1 is also activated in lung tissue of mechanically ventilated patients with ARDS. Deletion of Tsc2, a negative regulator of mTORC1, in epithelial cells impairs lung compliance during MV. Conversely, treatment with rapamycin at the time MV is initiated improves lung compliance without altering lung inflammation or barrier permeability. mTORC1 inhibition mitigates physiologic lung injury by preventing surfactant dysfunction during MV. Our data demonstrate that, in contrast to canonical mTORC1 activation under favorable growth conditions, activation of mTORC1 during MV exacerbates lung injury and inhibition of this pathway may be a novel therapeutic target to mitigate ventilator-induced lung injury during ARDS.


Assuntos
Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Surfactantes Pulmonares/metabolismo , Respiração Artificial/efeitos adversos , Síndrome do Desconforto Respiratório/patologia , Lesão Pulmonar Induzida por Ventilação Mecânica/patologia , Animais , Modelos Animais de Doenças , Humanos , Pulmão/metabolismo , Pulmão/patologia , Complacência Pulmonar/fisiologia , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Camundongos , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/fisiopatologia , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Lesão Pulmonar Induzida por Ventilação Mecânica/tratamento farmacológico , Lesão Pulmonar Induzida por Ventilação Mecânica/etiologia , Lesão Pulmonar Induzida por Ventilação Mecânica/fisiopatologia
8.
Cir. plást. ibero-latinoam ; 46(4): 441-448, oct.-dic. 2020. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-198726

RESUMO

INTRODUCCIÓN Y OBJETIVO: La microtia es un problema estético que conlleva una afección psicosocial en el desarrollo del paciente. La reconstrucción auricular mediante injerto costal autólogo es el procedimiento más usado. Determinamos los resultados quirúrgicos en nuestro hospital y el impacto en la calidad de vida de los pacientes con microtia sometidos a reconstrucción auricular con cartílago costal autólogo. MATERIAL Y MÉTODO: Estudio observacional, descriptivo, transversal y prolectivo en pacientes con diagnóstico de microtia uni o bilateral 1 año después de la reconstrucción. Evaluamos el resultado quirúrgico mediante cuestionario desarrollado y publicado por la primera autora, calificando características de apariencia estética de la oreja. Evaluamos la calidad de vida del paciente mediante cuestionario Glasgow Benefit Inventory, versión validada al español, en mayores de 15 años; para pacientes pediátricos utilizamos cuestionario Glasgow's Children's Benefit Inventory, versión traducida y validada por traductor especializado. RESULTADOS: Recogimos 83 pacientes con edad de 8 a 46 años. En la evaluación quirúrgica 13 pacientes (15.6%) tuvieron un resultado excelente, 27 (32.5%) bueno, 29 (34.9%) regular y 14 malo (16.8%). En la evaluación de calidad de vida encontramos en la escala total puntuación positiva en 78 pacientes (93.9%) y negativa en 5 (6%). CONCLUSIONES: El estudio presenta un panorama objetivo de las expectativas del cirujano sobre satisfacción y bienestar del paciente. Si bien solo encontramos resultados buenos y excelentes en el 48%, al revisar la escala de satisfacción encontramos puntaciones positivas, con bienestar en casi el 94%. Es importante que los pacientes conozcan nuestra preocupación por saber el impacto de la intervención y que podamos retroalimentar nuestra práctica quirúrgica. Hasta donde sabemos, este es el primer estudio en México que evalúa ambos aspectos


BACKGROUND AND OBJECTIVE: Microtia is not only an aesthetic problem but involves patient psychosocial development. The gold standard for auricular reconstruction is autologous costal cartilage. Our aim is to evaluate surgical outcomes and impact in quality of life after auricular reconstruction with autologous costal cartilage in microtia patients at our hospital. METHODS: Observational, descriptive, cross an prolective study on patients with uni or bilateral microtia 1 year after auricular reconstruction procedure. Surgical outcome was evaluated with a method previously published by the first author evaluating auricular aesthetic characteristics. Quality of life was evaluated with Glasgow Benefit Inventory, validated in Spanish, for over 15 years old patients; for pediatric patients we used the Glasgow's Children's Benefit Inventory, in a validated translated version. RESULTS: The study group was composed by 83 patients from 8 to 46 years old. Surgical outcome were excellent in 13 cases (15.6%), good in 27 (32.5%), regular in 29 cases (34.9%) and bad in 14 (16.8%). Quality of life had a positive total score in 78 cases (93.9%) and negative in 5 (6%). CONCLUSIONS: The study allows us an objective overview of surgeon's expectations regarding patient satisfaction and well-being. Although we only found good and excellent results in 48% of the patients, when reviewing the satisfaction scale we found positive scores in almost 94%. It`s important that patients know our concern about the impact of our intervention and to provide feedback on our surgical practice. As far as we know, this is the first study in Mexico evaluating both aspects


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Microtia Congênita/diagnóstico , Microtia Congênita/cirurgia , Qualidade de Vida/psicologia , Procedimentos de Cirurgia Plástica/métodos , México , Estudos Transversais , Escala de Resultado de Glasgow , Estudos de Validação como Assunto
9.
J Clin Invest ; 130(6): 3238-3252, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32154791

RESUMO

As treatment of the early, inflammatory phase of sepsis improves, post-sepsis immunosuppression and secondary infection have increased in importance. How early inflammation drives immunosuppression remains unclear. Although IFN-γ typically helps microbial clearance, we found that increased plasma IFN-γ in early clinical sepsis was associated with the later development of secondary Candida infection. Consistent with this observation, we found that exogenous IFN-γ suppressed macrophage phagocytosis of zymosan in vivo, and antibody blockade of IFN-γ after endotoxemia improved survival of secondary candidemia. Transcriptomic analysis of innate lymphocytes during endotoxemia suggested that NKT cells drove IFN-γ production by NK cells via mTORC1. Activation of invariant NKT (iNKT) cells with glycolipid antigen drove immunosuppression. Deletion of iNKT cells in Cd1d-/- mice or inhibition of mTOR by rapamycin reduced immunosuppression and susceptibility to secondary Candida infection. Thus, although rapamycin is typically an immunosuppressive medication, in the context of sepsis, rapamycin has the opposite effect. These results implicated an NKT cell/mTOR/IFN-γ axis in immunosuppression following endotoxemia or sepsis. In summary, in vivo iNKT cells activated mTORC1 in NK cells to produce IFN-γ, which worsened macrophage phagocytosis, clearance of secondary Candida infection, and mortality.


Assuntos
Tolerância Imunológica , Interferon gama/imunologia , Células Matadoras Naturais/imunologia , Células T Matadoras Naturais/imunologia , Sepse/imunologia , Transdução de Sinais/imunologia , Serina-Treonina Quinases TOR/imunologia , Animais , Antígenos CD1d/genética , Antígenos CD1d/imunologia , Candida/imunologia , Candidíase/genética , Candidíase/imunologia , Candidíase/patologia , Feminino , Humanos , Interferon gama/genética , Células Matadoras Naturais/patologia , Masculino , Camundongos , Camundongos Knockout , Células T Matadoras Naturais/patologia , Sepse/genética , Sepse/patologia , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/genética
10.
Rev. esp. cardiol. Supl. (Ed. impresa) ; 20(supl.A): 3-10, ene. 2020. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-197026

RESUMO

La fibrilación auricular es muy frecuente en el paciente anciano. Aunque existe una amplia experiencia con los antagonistas de la vitamina K, el empleo de estos fármacos en el paciente anciano presenta numerosas limitaciones, con una mayor susceptibilidad a las hemorragias y un peor control de la anticoagulación que en la población general. Los anticoagulantes orales de acción directa han demostrado ser una mejor alternativa terapéutica para los pacientes ancianos, no solo por su mayor simplicidad de uso, sino por sus mayores eficacia y seguridad en comparación con los antagonistas de la vitamina K, con datos que en general concuerdan con los ensayos clínicos fundamentales. Sin embargo, en el paciente anciano hay una tendencia al uso de dosis inadecuadas, generalmente por infradosificación, sobre todo con algunos de ellos, lo que conlleva una menor protección contra los ictus, sin una clara ventaja antihemorrágica. El rivaroxabán se ha estudiado ampliamente en la población anciana y no solo en ensayos clínicos, sino también en multitud de estudios en la práctica clínica real, con datos muy consistentes. En estos estudios, en comparación con los antagonistas de la vitamina K, se ha demostrado que el rivaroxabán reduce el riesgo de ictus sin un incremento de las hemorragias mortales, con lo que tiene un beneficio clínico neto favorable en la población con fibrilación auricular no valvular con mayor riesgo tromboembólico


Atrial fibrillation is common in elderly patients. Although vitamin K antagonists have been widely used for many years, they have a number of limitations in elderly patients, who are particularly susceptible to bleeding and in whom anticoagulation control is poorer than in the general population. Direct oral anticoagulants have been shown to be a better therapeutic option for these patients, not only because they are simpler to use, but also because they are more effective and safer than vitamin K antagonists. Moreover, their performance in practice is generally consistent with that in pivotal clinical trials. Nevertheless, there is a tendency to administer inappropriate doses to elderly patients, generally underdosing, particularly in certain subgroups. This can result in less protection against stroke without any clear reduction in bleeding risk. Rivaroxaban has been widely studied in the elderly population, not only in clinical trials, but also in a range of studies in routine clinical practice - findings have been highly consistent. According to these studies, and compared to vitamin K antagonists, rivaroxaban reduces the risk of stroke without increasing the rate of fatal bleeding, with a net clinical benefit in patients with nonvalvular atrial fibrillation and a high thromboembolic risk


Assuntos
Humanos , Múltiplas Afecções Crônicas/tratamento farmacológico , Anticoagulantes/administração & dosagem , Rivaroxabana/administração & dosagem , Fibrilação Atrial/tratamento farmacológico , Acidente Vascular Cerebral/prevenção & controle , Fragilidade/complicações , Fragilidade/tratamento farmacológico , Polimedicação , Envelhecimento/efeitos dos fármacos , 50293 , Vitamina K/antagonistas & inibidores , Antifibrinolíticos/administração & dosagem , Varfarina/administração & dosagem
12.
IEEE Trans Neural Netw Learn Syst ; 29(10): 5098-5110, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29994426

RESUMO

This paper presents a fully digital implementation of a memristor hardware (HW) simulator, as the core of an emulator, based on a behavioral model of voltage-controlled threshold-type bipolar memristors. Compared to other analog solutions, the proposed digital design is compact, easily reconfigurable, demonstrates very good matching with the mathematical model on which it is based, and complies with all the required features for memristor emulators. We validated its functionality using Altera Quartus II and ModelSim tools targeting low-cost yet powerful field-programmable gate array families. We tested its suitability for complex memristive circuits as well as its synapse functioning in artificial neural networks, implementing examples of associative memory and unsupervised learning of spatiotemporal correlations in parallel input streams using a simplified spike-timing-dependent plasticity. We provide the full circuit schematics of all our digital circuit designs and comment on the required HW resources and their scaling trends, thus presenting a design framework for applications based on our HW simulator.

13.
Gac Med Mex ; 152(1): 51-8, 2016.
Artigo em Espanhol | MEDLINE | ID: mdl-26927644

RESUMO

INTRODUCTION: Gingival recession is an unsightly condition due to root exposure. It can lead to dental hypersensitivity, root caries, and tooth loss. OBJECTIVE: To determine the influence of different clinical and periodontal parameters on the severity of gingival recession evaluated at four periods: initial, 6, 12, and 18 months of follow-up. MATERIAL AND METHODS: Forty patients with gingival recession were included in the study. Sociodemographic data, systemic diseases, harmful habits, dental hygiene habits, parafunctional habits, and orthodontic treatment were collected. Periodontal status (plaque index, gingival bleeding index, attached gingiva loss, pocket probing depth, and attachment loss) was also measured. RESULTS: None of the clinical parameters studied influenced the number of teeth with gingival recession. Smokers showed a higher number of teeth with attached gingiva loss (p=0.03). A direct relationship between the severity of gingival recession and plaque index (p=0.02) or 4-6 mm attachment loss (p=0.04) was observed. At six months of follow-up, gingival index was the only parameter that influenced the severity of gingival recession (p=0.01).


Assuntos
Retração Gengival/diagnóstico , Adolescente , Adulto , Idoso , Índice de Placa Dentária , Feminino , Retração Gengival/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Índice Periodontal , Valor Preditivo dos Testes , Índice de Gravidade de Doença , Inquéritos e Questionários , Adulto Jovem
14.
Appl Opt ; 53(31): 7551-5, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25402923

RESUMO

We demonstrate a ladar with 0.5 m class range resolution obtained by integrating a continuous-wave optical phased-array transmitter with a Geiger-mode avalanche photodiode receiver array. In contrast with conventional ladar systems, an array of continuous-wave sources is used to effectively pulse illuminate a target by electro-optically steering far-field fringes. From the reference frame of a point in the far field, a steered fringe appears as a pulse. Range information is thus obtained by measuring the arrival time of a pulse return from a target to a receiver pixel. This ladar system offers a number of benefits, including broad spectral coverage, high efficiency, small size, power scalability, and versatility.

15.
Phys Rev Lett ; 112(14): 144501, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24765971

RESUMO

Rotating Rayleigh-Bénard convection exhibits, in the limit of rapid rotation, a turbulent state known as geostrophic turbulence. This state is present for sufficiently large Rayleigh numbers representing the thermal forcing of the system, and is characterized by a leading order balance between the Coriolis force and pressure gradient. This turbulent state is itself unstable to the generation of depth-independent or barotropic vortex structures of ever larger scale through a process known as spectral condensation. This process involves an inverse cascade mechanism with a positive feedback loop whereby large-scale barotropic vortices organize small scale convective eddies. In turn, these eddies provide a dynamically evolving energy source for the large-scale barotropic component. Kinetic energy spectra for the barotropic dynamics are consistent with a k-3 downscale enstrophy cascade and an upscale cascade that steepens to k-3 as the box-scale condensate forms. At the same time the flow maintains a baroclinic convective component with an inertial range consistent with a k-5/3 spectrum. The condensation process resembles a similar process in two dimensions but is fully three-dimensional.

16.
Cell Transplant ; 22(8): 1381-94, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23044223

RESUMO

Mesenchymal stromal cell (MSC) immunosuppressive properties have been applied to treat graft-versus-host disease (GVHD) in allogeneic hematopoietic stem cell transplants (HSCTs). We have previously demonstrated that MSC infusions early after haplo-HSCT prevent GVHD in a haploidentical-HSCT mouse model. Now, we investigated the impact that MSCs' immunosuppressive properties have on the graft-versus-leukemia (GVL) effect. First, to mimic a chronic myeloid leukemia (CML) relapse after a haploidentical HSCT, lethally irradiated mice were coinfused with haploidentical donor bone marrow cells plus syngenic hematopoietic progenitors transduced with a retroviral vector encoding both the BCR/ABL oncogene and the ΔNGFR marker gene. As expected, a CML-like myeloproliferative syndrome developed in all the recipient animals. The addition of haploidentical splenocytes to the transplanted graft prevented CML development by a GVL effect, and all transplanted recipients died of GVHD. This GVL mouse model allowed us to investigate the impact of MSCs infused to prevent GVHD on days 0, 7, and 14 after HSCT, on the GVL effect, expecting an increase in leukemic relapse. Strikingly, a high mortality of the recipients was observed, caused by GVHD, and only few leukemic cells were detected in the recipient animals. In contrast, GVHD prevention by MSCs in the absence of BCR/ABL leukemic cells resulted in a significant survival of the recipients. In vitro data pointed to an inability of MSCs to control strong CTLs responses against BCR/ABL. Our results show that, although an evident increase in leukemic relapses induced by MSCs could not be detected, they showed a reduced efficacy in preventing GVHD that precluded us to draw clear conclusions on MSCs' impact over GVL effect.


Assuntos
Transplante de Medula Óssea , Doença Enxerto-Hospedeiro/prevenção & controle , Haploidia , Leucemia/terapia , Células-Tronco Mesenquimais/citologia , Adenoviridae/metabolismo , Animais , Medula Óssea/patologia , Proliferação de Células , Modelos Animais de Doenças , Feminino , Proteínas de Fusão bcr-abl/metabolismo , Transplante de Células-Tronco Hematopoéticas , Leucemia/sangue , Camundongos , Camundongos Endogâmicos C57BL , Recidiva , Retroviridae/metabolismo , Baço/patologia , Linfócitos T/metabolismo , Transdução Genética , Resultado do Tratamento
17.
Opt Lett ; 37(23): 5006-8, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23202119

RESUMO

We demonstrate 40 W coherently combined output power in a single diffraction-limited beam from a one-dimensional 47-element array of angled-facet slab-coupled optical waveguide amplifiers at 1064 nm. The output from each emitter was collimated and overlapped onto a diffractive optical element combiner using a common transform lens. Phase locking was achieved via active feedback on each amplifier's drive current to maximize the power in the combined beam. The combining efficiency at all current levels was nearly constant at 87%.

18.
Opt Express ; 20(16): 17311-8, 2012 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-23038284

RESUMO

Beam steering at high speed and high power is demonstrated from a 6-element optical phased array using coherent beam combining (CBC) techniques. The steering speed, defined as the inverse of the time to required to sweep the beam across the steering range, is 40 MHz and the total power is 396 mW. The measured central lobe FWHM width is 565 µrad. High on-axis intensity is maintained periodically by phase-locking the array via a stochastic-parallel-gradient-descent (SPGD) algorithm. A master-oscillator-power-amplifier (MOPA) configuration is used where the amplifier array elements are semiconductor slab-coupled-optical-waveguide-amplifiers (SCOWAs). The beam steering is achieved by LiNbO(3) phase modulators; the phase-locking occurs by current adjustment of the SCOWAs. The system can be readily scaled to GHz steering speed and multiwatt-class output.

19.
Appl Opt ; 51(11): 1724-8, 2012 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-22505163

RESUMO

Active coherent beam combining of laser oscillators is an attractive way to achieve high output power in a diffraction limited beam. Here we describe an active beam combining system used to coherently combine 21 semiconductor laser elements with an 81% beam combining efficiency in an external cavity configuration compared with an upper limit of 90% efficiency in the particular configuration of the experiment. Our beam combining system utilizes a stochastic parallel gradient descent (SPGD) algorithm for active phase control. This work demonstrates that active beam combining is not subject to the scaling limits imposed on passive-phasing systems.

20.
Phys Rev Lett ; 109(25): 254503, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23368470

RESUMO

We demonstrate, via simulations of asymptotically reduced equations describing rotationally constrained Rayleigh-Bénard convection, that the efficiency of turbulent motion in the fluid bulk limits overall heat transport and determines the scaling of the nondimensional Nusselt number Nu with the Rayleigh number Ra, the Ekman number E, and the Prandtl number σ. For E << 1 inviscid scaling theory predicts and simulations confirm the large Ra scaling law Nu-1 ≈ C(1)σ(-1/2)Ra(3/2)E(2), where C(1) is a constant, estimated as C(1) ≈ 0.04 ± 0.0025. In contrast, the corresponding result for nonrotating convection, Nu-1 ≈ C(2)Ra(α), is determined by the efficiency of the thermal boundary layers (laminar: 0.28 ≤ α ≤ 0.31, turbulent: α ~ 0.38). The 3/2 scaling law breaks down at Rayleigh numbers at which the thermal boundary layer loses rotational constraint, i.e., when the local Rossby number ≈ 1. The breakdown takes place while the bulk Rossby number is still small and results in a gradual transition to the nonrotating scaling law. For low Ekman numbers the location of this transition is independent of the mechanical boundary conditions.

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