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2.
Phys Rev Lett ; 130(10): 108001, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36962043

RESUMO

We present a femtosecond time-resolved optical pump-soft x-ray probe photoemission study in which we follow the dynamics of charge transfer at the interface of water and anatase TiO_{2}(101). By combining our observation of transient oxygen O 1s core level peak shifts at submonolayer water coverages with Ehrenfest molecular dynamics simulations we find that ultrafast interfacial hole transfer from TiO_{2} to molecularly adsorbed water is completed within the 285 fs time resolution of the experiment. This is facilitated by the formation of a new hydrogen bond between an O_{2c} site at the surface and a physisorbed water molecule. The calculations fully corroborate our experimental observations and further suggest that this process is preceded by the efficient trapping of the hole at the surface of TiO_{2} by hydroxyl species (-OH), that form following the dissociative adsorption of water. At a water coverage exceeding a monolayer, interfacial charge transfer is suppressed. Our findings are directly applicable to a wide range of photocatalytic systems in which water plays a critical role.

3.
Eur J Intern Med ; 112: 70-76, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36948977

RESUMO

OBJECTIVE: Hydroxychloroquine (HCQ) is one of the most used drugs in patients with systemic lupus erythematosus (SLE). In these patients, where heart involvement is common, cardiac HCQ toxicity may lead to fatal outcomes. The aim of this work is to study the influence of cumulative HCQ (cHCQ) in a selected group of patients with SLE and its association with electrocardiographic (EKG) abnormalities. METHODS: Single-center retrospective, observational study in which data were collected from the medical records of consecutive patients with a diagnosis of SLE who started treatment with HCQ and who had a 12-lead EKG before starting treatment and during follow-up. EKG abnormalities were grouped as conduction or structural abnormalities. The association of cHCQ with the occurrence of EKG disturbances was analyzed together with other demographic and clinical variables through univariate and multivariate logistic regression models. RESULTS: 105 patients were selected with median cHCQ of 913 g. The sample was classified into two groups, above or below 913 g. Significantly, more conduction disturbances were observed in the group above the median (OR: 2.89; 95%CI: 1.01-8.23). In the multivariate analysis, the OR per 100 g of cHCQ dose was 1.06 (95%CI: 0.99-1.14). Age was the only variable associated with conduction disturbances. There were no significant differences in the development of structural abnormalities and a tendency for more high-grade atrioventricular block was shown. CONCLUSION: Our study suggests an association between the cHCQ and the development of EKG conduction disturbances that disappears after multivariate adjustment. No increased number of structural abnormalities was observed.


Assuntos
Antirreumáticos , Lúpus Eritematoso Sistêmico , Humanos , Hidroxicloroquina/efeitos adversos , Antirreumáticos/efeitos adversos , Estudos Retrospectivos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/complicações , Análise Multivariada
4.
Artigo em Inglês | MEDLINE | ID: mdl-35409625

RESUMO

Improving access to sexual health services is critical in light of rising sexually transmitted infections (STIs). We evaluated a hub-and-spoke model for improving access to sexual health services in three general practices in Victoria, Australia. The primary outcome was the impact on HIV and STI (chlamydia, gonorrhoea, syphilis) testing. Segmented linear regression analysis was conducted to examine the trends in the total HIV/STI tests pre- (from January 2019 to June 2020) and post-implementation (from July 2020 to July 2021). We evaluated the feasibility and acceptability of integrating this model into the general practices using semi-structured individual interviews. There was a statistically significant rise in testing for HIV and STIs in all general practices: post-implementation, there was an increase of an average of 11.2 chlamydia tests per month (p = 0.026), 10.5 gonorrhoea tests per month (p = 0.001), 4.3 syphilis tests per month (p = 0.010), and 5.6 HIV tests per month (p = 0.010). Participants reported increases in knowledge level and confidence in offering STI testing and managing a greater variety of sexual health cases. This study demonstrates the feasibility of implementing a hub-and-spoke model to enable GPs to deliver sexual health care with support from a sexual health specialist service.


Assuntos
Medicina Geral , Gonorreia , Infecções por HIV , Infecções Sexualmente Transmissíveis , Sífilis , Gonorreia/diagnóstico , Gonorreia/epidemiologia , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Serviços de Saúde , Humanos , Comportamento Sexual , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Vitória/epidemiologia
5.
Phys Chem Chem Phys ; 23(32): 17129-17133, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34355230

RESUMO

Theoretical calculations are an effective strategy to complement and understand the experimental results in atomistic detail. Ehrenfest molecular dynamics simulations based on the real-time time-dependent density functional tight-binding (RT-TDDFTB) approach are performed to reveal for the first time the electron dynamics for the charge separation of pyrene-functionalized middle-sized Au70S20(PH3)16 and large-sized Au108S24(PR3)16 (R = H, CH3, C2H5, C6H5) clusters. The proposed mechanism uncovers an ultrafast and irreversible photoinduced charge transfer from the gold nanocluster (GNC) unit to the pyrene derivative in all cases. By a Fourier transform analysis of the dynamics, the effect of vibronic couplings is highlighted. The Au108S24(PPh3)15PPh2Pyr system exhibits the best performance for charge separation.

6.
Nanoscale ; 13(14): 6786-6797, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33690747

RESUMO

The electron flow between a metallic aggregate and an organic molecule after excitation with light is a crucial step on which hybrid photovoltaic nanomaterials are based. So far, designing such devices with the help of theoretical approaches has been heavily limited by the computational cost of quantum dynamics models able to track the evolution of the excited states over time. In this article, we present the first application of the time-dependent density functional tight-binding (TD-DFTB) method for an experimental nanometer-sized gold-organic system consisting of a hexyl-protected Au25 cluster labelled with a pyrene fluorophore, in which the fluorescence quenching of the pyrene is attributed to the electron transfer from the metallic cluster to the dye. The full quantum rationalization of the electron transfer is attained through quantum dynamics simulations, highlighting the crucial role of the protecting ligand shell in electron transfer, as well as the coupling with nuclear movement. This work paves the way towards the fast and accurate theoretical design of optoelectronic nanodevices.

7.
Proc Natl Acad Sci U S A ; 115(46): 11706-11711, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30373832

RESUMO

Some commonly referenced thermal-mechanical models of current subduction zones imply temperatures that are 100-500 °C colder at 30-80-km depth than pressure-temperature conditions determined thermobarometrically from exhumed metamorphic rocks. Accurately inferring subduction zone thermal structure, whether from models or rocks, is crucial for predicting metamorphic reactions and associated fluid release, subarc melting conditions, rheologies, and fault-slip phenomena. Here, we compile surface heat flow data from subduction zones worldwide and show that values are higher than can be explained for a frictionless subduction interface often assumed for modeling. An additional heat source--likely shear heating--is required to explain these forearc heat flow values. A friction coefficient of at least 0.03 and possibly as high as 0.1 in some cases explains these data, and we recommend a provisional average value of 0.05 ± 0.015 for modeling. Even small coefficients of friction can contribute several hundred degrees of heating at depths of 30-80 km. Adding such shear stresses to thermal models quantitatively reproduces the pressure-temperature conditions recorded by exhumed metamorphic rocks. Comparatively higher temperatures generally drive rock dehydration and densification, so, at a given depth, hotter rocks are denser than colder rocks, and harder to exhume through buoyancy mechanisms. Consequently--conversely to previous proposals--exhumed metamorphic rocks might overrepresent old-cold subduction where rocks at the slab interface are wetter and more buoyant than in young-hot subduction zones.

8.
J Nephropathol ; 6(3): 240-247, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28975107

RESUMO

BACKGROUND: Risk factors for cytomegalovirus (CMV) disease in renal transplant recipients have been evaluated in industrialized countries with relatively low CMV seroprevalence. OBJECTIVES: We aimed to determine which factors are related to this illness in a high CMV seroprevalence country. PATIENTS AND METHODS: A case-control study was performed with data from a 5-year follow-up of 260 kidney transplant recipients at our center. Odds ratios were calculated using the Mantel-Haenszel method. RESULTS: A total of 25 cases of CMV disease occurred during the study period. Recipient age greater than 55 years old (odds ratio: 4.95, 95% CI: 1.44-17.0) and use of thymoglobulin (odds ratio: 4.84; 95% CI: 1.10-21.39) were the only independent predictors for CMV disease. There was not any relationship between the previous serologic status of both donor and receptor and the occurrence of CMV disease. We did not observe any association between the immunosuppressive regimens and CMV disease, except for thymoglobulin. CONCLUSIONS: Only recipient age and thymoglobulin administration were related to CMV disease. Further studies are needed to determine if prophylactic treatment confers clinical benefit in this subset of patients.

11.
Vis Neurosci ; 24(5): 757-61, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17915042

RESUMO

We measured the latency of 35 cells from V1 in two rhesus monkeys, to dynamic random dot stimuli monocular and binocularly presented. Mean latencies after non-dominant eye stimulation (97.9 ms) were longer than those for dominant eye (78.2 ms) and binocular (70.7 ms) stimulation. Differences between latencies for dominant eye and binocular stimulation were not statistically significant. For dominant eye, there was a significant statistical correlation between dominance strength and latency (R = -0.36; p = 0.03). We failed to find significant statistical differences between latencies for cells with temporal and nasal dominant receptive-field. We conclude that, in V1, the response latency is largely determined by the dominant eye, whereas interocular interactions do not seem to play a relevant role regarding response latency.


Assuntos
Dominância Ocular/fisiologia , Córtex Visual/fisiologia , Animais , Estimulação Elétrica , Eletrofisiologia , Fixação Ocular/fisiologia , Macaca mulatta , Microeletrodos , Neurônios/fisiologia , Estimulação Luminosa , Visão Binocular/fisiologia , Visão Monocular/fisiologia , Córtex Visual/citologia , Campos Visuais/fisiologia
12.
Telemed J E Health ; 13(3): 287-92, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17603831

RESUMO

Diabetes and systemic hypertension are among the most prevalent diseases in developed countries. Since both can produce retinal involvement, they often cause long waiting lists for ophthalmologist consultation. The inspection of digital eye fundus images by a general practitioner would help to divert only those cases with retinal involvement. To evaluate this possibility we studied the agreement between the assessment of digital fundus images made by a general practitioner and an ophthalmologist. A total of 776 fundus images of 194 patients were inspected by both observers looking for retinal lesions consistent with diabetic or hypertensive retinopathy. Contingency tables were made, and the agreement between both observers was assessed by using the kappa index. We found good agreement between the findings reported by the general practitioner and those reported by the ophthalmologist (kappa = 0.80 for patients with only diabetes, 1.00 for patients with only hypertension, and 0.79 for patients with both diseases). Our results suggest that the inspection of digital retinal images by a general practitioner could reduce the number of referred patients for specialist consultation.


Assuntos
Técnicas de Diagnóstico Oftalmológico/normas , Medicina de Família e Comunidade/normas , Fundo de Olho , Bibliotecas Digitais , Oftalmologia/normas , Consulta Remota , Doenças Retinianas/diagnóstico , Telerradiologia , Humanos , Encaminhamento e Consulta , Estudos Retrospectivos , Espanha
13.
Eur J Neurosci ; 25(8): 2536-46, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17445249

RESUMO

We are able to judge the direction of movement and orientation of objects because they have contrast-defined edges. However, we are also able to perceive the orientation and direction of movement of stereobars made of random dot stereograms in the absence of contrast-defined edges. We recorded 207 disparity-sensitive cells from visual areas V1 and V2 of two Macaca mulatta monkeys while performing an attentive fixation task. Luminance defined bars and random-dot stereo-defined bars were used to assess direction and orientation selectivity of these cells. Orientation and direction preference for luminance bars and for stereobars showed a statistically significant relationship (r=0.83, P<0.01 for direction; r=0.63, P<0.01 for orientation). However, disparity-sensitive cells from these areas seem to be more sensitive to luminance than to stereobars regarding orientation and direction of movement. Similar results were obtained when the two areas were considered separately. Our results show that cells in areas V1 and V2 of the monkey visual cortex are able to detect the orientation and direction of movement of stereobars in a manner similar to those of luminance-defined bars. This finding is relevant because to detect the direction and orientation of stereobars a comparison between left and right eye inputs is required.


Assuntos
Percepção de Movimento/fisiologia , Orientação/fisiologia , Percepção Espacial/fisiologia , Córtex Visual/fisiologia , Animais , Comportamento Animal/fisiologia , Eletrofisiologia , Macaca mulatta , Masculino
14.
Neuroreport ; 17(6): 565-9, 2006 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-16603912

RESUMO

We mapped the receptive fields of 49 cells from primary visual cortex and 19 cells from medial superior temporal cortex in two awake monkeys. The receptive field structures we obtained lasted a mean time of 32.7 ms in primary visual cortex and 38.4 ms in medial superior temporal cortex, showing no statistical difference. This result suggests that both areas have the same time requirements for processing visual information. In primary visual cortex, 100% of cells had conformed the receptive field structure at 65 ms pre-spike, whereas in medial superior temporal cortex it occurred at 150 ms. In both areas, cells with shorter response latencies had receptive field structures with longer durations. This may indicate that cells tend to synchronize their output to other areas.


Assuntos
Neurônios/fisiologia , Lobo Temporal/citologia , Córtex Visual/citologia , Campos Visuais/fisiologia , Potenciais de Ação/fisiologia , Análise de Variância , Animais , Macaca mulatta , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Percepção Visual/fisiologia
15.
J Telemed Telecare ; 11(7): 347-53, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16238836

RESUMO

We developed a simple Web-based program to make measurements on displayed photographs between several ocular and periocular landmarks. The measurements were: (1) vertical distance between the margin of the upper and lower eyelids (palpebral aperture), (2) distance between the lower eyelid margin and the inferior corneal margin (palpebro-limbar distance); (3) interpupillary distance; (4) ocular proptosis. We measured the distances using the Web program and compared them with manual measurements on the subject's face. The measurements involved 102 eyes of 51 patients with a variety of ophthalmic conditions. There was good agreement between manual and computer measurements. For example, for manual measurements in 49 patients, we obtained interpupillary distances ranging from 45 to 69 mm (mean 61, SD 6), whereas for computer measurements we found values ranging from 42 to 49 mm (mean 59, SD 6). The mean of the differences between manual and computer measurements was -2.0 mm (SD 4.3) and the 95% limits of agreement were -6.5 to 10.5 mm. Thus, computer measurements tended to give a higher reading by between 0.8 and 3.2 mm (95% confidence interval for the difference). Web-based software may be used to perform measurements on two-dimensional pictures and the technique appears to be suitable for telemedical purposes.


Assuntos
Olho/anatomia & histologia , Internet , Software , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria , Criança , Pré-Escolar , Estudos de Viabilidade , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade
16.
J Telemed Telecare ; 11(1): 23-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15829040

RESUMO

We searched the MEDLINE database for publications about telemedicine from 1966 to 2003. Only publications with a first institutional address in Spain and from journals listed in the JCR Science Edition 2002 were included in the study. A total of 118 publications were found. The first publication appeared in 1988 and publication output showed a sudden increase starting in 1995, reaching a maximum in 2002 with 21 publications. The number of authors per publication in non-multicentre studies ranged from 1 to 14 (median 6.5). Most authors (79%) contributed to only a single publication; 10% of authors participated in three or more publications. Most publications were full papers (88%). The most active Autonomous Community in the number of publications relative to inhabitants was Galicia (0.91 publications per 100,000 inhabitants). The Community that produced the highest absolute number of publications was Madrid (29% of the total). The mean impact factor of the journals in which the publications appeared was 0.961. Production of telemedicine publications in Spain has followed the same temporal course as has been observed worldwide. There is an unequal geographical and institutional distribution of publications. The highest production is concentrated in a few institutions and only a small number of authors show steady research activity.


Assuntos
Bibliometria , Publicações Periódicas como Assunto/estatística & dados numéricos , Editoração/estatística & dados numéricos , Telemedicina/estatística & dados numéricos , Humanos , Espanha , Telemedicina/tendências
17.
Invest Ophthalmol Vis Sci ; 46(4): 1533-9, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15790926

RESUMO

PURPOSE: To explore the neural mechanisms underlying disparity sensitivity in complex cells of the macaque visual cortex, the relationship between interocular receptive field (RF) positional shift and disparity sensitivity was studied in area V1. METHODS: Single-unit recordings were made from area V1 of awake Macaca mulatta. Monocular RFs were mapped by means of a reverse cross-correlation technique, and their centers were determined after performing a bidimensional Gaussian function fitting. Interocular RF shifts were calculated for both bright and dark stimuli. Similarly, Gabor adjustments were obtained from disparity profiles to bright and dark dynamic random-dot stereograms (RDSs). RESULTS: Twenty-five complex cells were studied. The response profiles to disparity were similar for bright and dark RDSs. Interocular RF positional shift correlated significantly with both the peaks of Gabor fittings of disparity-sensitivity profiles and the peaks of the Gaussian envelopes of these Gabor fittings. Correlation between interocular RF positional shift and the peaks of the Gaussian envelopes was stronger than correlation between interocular RF positional shift and peaks of Gabor fittings. CONCLUSIONS: Interocular shift of monocular RFs is more related to the center of the range of disparities to which the cell is sensitive, than to the preferred disparity of the cell.


Assuntos
Retina/fisiologia , Disparidade Visual/fisiologia , Visão Monocular/fisiologia , Córtex Visual/fisiologia , Campos Visuais/fisiologia , Animais , Eletrofisiologia , Macaca mulatta , Microeletrodos , Modelos Neurológicos , Estimulação Luminosa , Vias Visuais/fisiologia
18.
Blood ; 105(4): 1622-31, 2005 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-15507526

RESUMO

To enhance the in vivo antitumor activity of adoptively transferred, CD19-specific chimeric antigen receptor (CAR)-redirected cytotoxic T lymphocytes (CTLs), we studied the effect of restimulating CAR(+) CTLs through their endogenous virus-specific T-cell antigen receptor (TcR) by the cotransfer of engineered T-cell antigen-presenting cells (T-APCs). Using influenza A matrix protein 1 (MP1) as a model antigen, we show that ex vivo-expanded CD4(+) and CD8(+) T-APCs expressing a hygromycin phosphotransferase-MP1 fusion protein (HyMP1) process and present MP1 to autologous human leukocyte antigen (HLA)-restricted, MP1-specific CD4(+) and CD8(+) CTL precursors. The MP1-specific CTLs are amenable to subsequent genetic modification to express a CD19-specific CAR, designated CD19R, and acquire HLA-unrestricted reactivity toward CD19(+) leukemia and lymphoma tumor targets while maintaining HLA-restricted MP1 specificity. The restimulation of MP1xCD19 dual-specific CTLs in vivo by the adoptive transfer of irradiated HyMP1(+) T-APCs resulted in the enhanced antilymphoma potency of bispecific effector cells, as measured by elimination of the biophotonic signal of established firefly luciferase-expressing Burkitt lymphoma xenografts in nonobese diabetic/severe combined immunodeficiency (NOD/scid) animals compared with control groups restimulated by Hy(+)MP1(neg) T-APCs. Engineered T-APCs are a novel and versatile antigen-delivery system for generating antigen-specific T cells in vitro and enhancing the in vivo effector functioning of CAR-redirected antitumor effector cells.


Assuntos
Apresentação de Antígeno , Antígenos CD19/fisiologia , Epitopos de Linfócito T/imunologia , Linfoma/imunologia , Linfoma/terapia , Linfócitos T Citotóxicos/imunologia , Linfócitos T/transplante , Proteínas da Matriz Viral/imunologia , Transferência Adotiva/métodos , Animais , Apresentação de Antígeno/genética , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Células Apresentadoras de Antígenos/virologia , Antígenos CD19/biossíntese , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Linhagem Celular , Linhagem Celular Transformada , Técnicas de Cocultura , Testes Imunológicos de Citotoxicidade/métodos , Epitopos de Linfócito T/genética , Técnicas de Transferência de Genes , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/imunologia , Células K562 , Ativação Linfocitária/genética , Linfoma/genética , Linfoma/virologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Plasmídeos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/virologia , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Citotóxicos/virologia , Proteínas da Matriz Viral/biossíntese , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/metabolismo
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