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1.
Bioinformatics ; 37(13): 1930-1931, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-33051645

RESUMO

SUMMARY: FCSlib is an open-source R tool for fluorescence fluctuation spectroscopy data analysis. It encompasses techniques such as Fluorescence Correlation Spectroscopy, Number and Brightness, Pair Correlation Function and Pair Correlation of Molecular Brightness. AVAILABILITY AND IMPLEMENTATION: Source code available at https://cran.r-project.org/web/packages/FCSlib/ for Linux, Windows and macOS platforms. Sample data as well as a user's guide are available at https://github.com/FCSlib/FCSlib. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Software , Análise Espectral
2.
Int Ophthalmol ; 42(3): 747-756, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34622374

RESUMO

KEY MESSAGES: Visual acuity is the most used method to assess visual function in children. Contrast sensitivity complements the information provided for visual acuity, but it is not commonly used in clinical practice. Digital devices are increasingly used as a method to evaluate visual function, due to multiple advantages. Testing with these devices can improve the evaluation of visual development in children from a few months of age. Visual acuity and contrast sensitivity tests, using eye tracking technology, are able to measure visual function in children across a wide range of ages, objectively, quickly and without need of an experienced examiner. PURPOSE: To report age-normative values for grating visual acuity and contrast sensitivity in healthy children using a digital device with eye tracking technology and to validate the grating acuity test. METHODS: In the first project of the study, we examined healthy children aged between 6 months and 7 years with normal ophthalmological assessment. Grating visual acuity (VA) and contrast sensitivity (CS) were assessed using a preferential gaze paradigm with a DIVE (Device for an Integral Visual Examination) assisted with eye tracking technology to provide age norms. For the validation project, we compared LEA grating test (LGT) with DIVE VA in a group of children aged between 6 months and 4 years with normal and abnormal visual development. RESULTS: Fifty-seven children (2.86 ± 1.55 years) were examined with DIVE VA test and 44 successfully completed DIVE CS test (3.06 ± 1.41 years). Both, VA and CS values increased with age, mainly along the first two years of life. Sixty-nine patients (1.34 ± 0.61 years) were included in the DIVE VA test validation. The mean difference between LGT and DIVE VA was - 1.05 ± 4.54 cpd with 95% limits of agreement (LoA) of - 9.95-7.84 cpd. Agreement between the two tests was higher in children younger than 1 year with a mean difference of - 0.19 ± 4.02 cpd. CONCLUSIONS: DIVE is an automatic, objective and reliable tool to assess several visual function parameters in children, and it has good agreement with classical VA tests, especially for the first stage of life.


Assuntos
Sensibilidades de Contraste , Oftalmologia , Criança , Tecnologia de Rastreamento Ocular , Humanos , Lactente , Testes Visuais/métodos , Acuidade Visual
3.
Nanotechnology ; 32(5): 055604, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33065556

RESUMO

Nanostructured hybrid materials (NHMs) are promising candidates to improve the performance of several materials in different applications. In the case of optoelectronic technologies, the ability to tune the optical absorption of such NHMs is an appealing feature. Along with the capacity to transform the absorbed light into charge carriers (CC), and their consequently efficient transport to the different electrodes. In this regard, NHM based on graphene-like structures and semiconductor QDs are appealing candidates, assuming the NHMs retain the light absorption and CC photogeneration properties of semiconductor QDs, and the excellent CC transport properties displayed by graphene-like materials. In the current work a solution-processed NHM using PbS quantum dots (QDs) and graphene oxide (GO) was fabricated in a layer-by-layer configuration by dip-coating. Afterwards, these NHMs were reduced by thermal or chemical methods. Reduction process had a direct impact on the final optoelectronic properties displayed by the NHMs. All reduced samples displayed a decrement in their resistivity, particularly the sample chemically reduced, displaying a 107 fold decrease; mainly attributed to N-doping in the reduced graphene oxide (rGO). The optical absorption coefficients also showed a dependence on the rGO's reduction degree, with reduced samples displaying higher values, and sample thermally reduced at 300 °C showing the highest absorption coefficient, due to the combined absorption of unaltered PbS QDs and the appearance of sp2 regions within rGO. The photogenerated current increased in most reduced samples, displaying the highest photocurrent the sample reduced at 400 °C, presenting a 2500-fold increment compared to the NHM before reduction, attributed to an enhanced CC transfer from PbS QDs to rGO, as a consequence of an improved band alignment between them. These results show clear evidence on how the optoelectronic properties of NHMs based on semiconductor nanoparticles and rGO, can be tuned based on their configuration and the reduction process parameters.

4.
Nanotechnology ; 30(39): 395601, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31234156

RESUMO

In the present study core-shell PEDOT:PSS-polyvinylpirrolidone nanofibers were synthesized by coaxial electrospinning. These fibers were doped with different solvents (dimethylsulphoxide, dimethyl sulfoxide (DMSO), isopropyl alcohol (IPA), and ethylene glycol), and PbS nanoparticles at different concentrations; additionally, the coaxial electrospinning setup process was inverted in order to exchange the phases comprising the core-shell morphology. Experimental results showed that DMSO and IPA solvents produced a change in the PEDOT:PSS phase from its benzoid structure to a more conjugated (quinoid) one. The synthesized samples displayed an increment in the conductance of the composite nanofibers, based on a more conjugated structure of the PEDOT:PSS phase, and a better dispersion of the PbS nanoparticles within the nanofibers; this increment was, under certain synthesis conditions, up to three orders of magnitude higher than in the case of the nanofibers with no solvent, nor nanoparticles, added. Photoresponse also showed a clear increment in the value of the photogenerated current as the concentration of the nanoparticles increased. Inverting the arrangement of the core-shell phases in the nanofibers increased the conductance and the photogenerated current in the cases analyzed. These results show novel evidence on the capability of tuning the conductance and photoresponse of composite core-shell nanofibers, based on the doping of the PEDOT:PSS phase with different solvents and PbS nanoparticles, and the arrangement of the core-shell phases. Tailoring the optoelectronic properties of conductive, flexible nanofibers is a desirable competence in technological areas such as transparent flexible conductors, biosensors and tissue engineering.

5.
J Eur Acad Dermatol Venereol ; 32(11): 1879-1886, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29888465

RESUMO

Photodermatoses represent a heterogeneous collection of disorders unified by the characteristic of being provoked through exposure to ultraviolet radiation. Generally, these conditions are classified into the following categories: immunologically mediated photodermatoses, chemical- and drug-induced photosensitivity, photoaggravated dermatoses and photosensitivity associated with defective DNA repair mechanisms or chromosomal instabilities. The list of photodermatoses is extensive, and each individual photodermatosis is understood to a different extent. Regardless, there exists a paucity of information with regards to the clinical presentation among those with skin of colour. With ever-changing global demographics, recognition of photosensitive disorders in a diverse population is essential for accurate diagnoses and therapeutic guidance. The scope of this article seeks to review the epidemiology and clinical variability in presentation of such photodermatoses in patients with skin of colour.


Assuntos
Dermatite Fotoalérgica/diagnóstico , Dermatite Fototóxica/diagnóstico , Pigmentação da Pele/fisiologia , Luz Solar/efeitos adversos , Raios Ultravioleta/efeitos adversos , Dermatite Fotoalérgica/epidemiologia , Dermatite Fotoalérgica/patologia , Dermatite Fototóxica/epidemiologia , Dermatite Fototóxica/patologia , Feminino , Humanos , Masculino , Transtornos de Fotossensibilidade/diagnóstico , Transtornos de Fotossensibilidade/epidemiologia , Transtornos de Fotossensibilidade/patologia , Exame Físico/métodos , Prevalência , Prognóstico , Medição de Risco
9.
J Acoust Soc Am ; 144(1): 222, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30075687

RESUMO

Experimental data on ultrasonic atomization of distilled water in a frequency range from 5 to 50 kHz are presented. A good agreement was found with the predictions of Rajan and Pandit [Ultrasonics 39, 235-255 (2001)] for the atomized primary drop size as a function of frequency. The correlation of atomization drop size for different frequencies is useful when producing nanoparticles, spray drying of suspensions, and covering of surfaces using different liquid products. Determining the displacement amplitude threshold for atomization at different frequencies is valuable in designing ultrasonic atomization systems. It is essential to measure the displacement amplitude of the atomizing surface rather that power applied to the transducer because the former is absolute while the latter depends on the efficiency of the transducer and other design parameters. As previous predictions for atomization threshold proved inaccurate, an empirical expression is proposed (based on the authors' measurements) to predict the amplitude atomization threshold for the studied frequency range.

10.
Clin Radiol ; 72(11): 993.e1-993.e6, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28705329

RESUMO

AIM: To determine the effect of different numbers of projection images in C-arm cone-beam computed tomography (CBCT) on diagnostic content and image quality in patients undergoing angiographic embolotherapy for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: A total of 29 patients who underwent contrast-enhanced conventional multidetector CT (MDCT) within 6 weeks prior to CBCT acquired during embolotherapy for HCC between 2010 and 2013 were included in the study. CBCT was acquired in each patient using a 5-s (248 projection images) or 8-s (396 projection images) protocol. Anonymised images were reviewed independently by an interventional radiologist blinded to CBCT group. MDCT was used as a reference to the patient's anatomy, and performance of CBCT was compared to that of MDCT in each group. The level of concordance between CBCT and MDCT within each group was assessed for the following variables: number of foci >1 cm, largest tumour diameter, highest order branching vessel identified, image quality, diagnostic quality, signal-to-noise ratio, and contrast-to-noise ratio (CNR). CBCT radiation dose was recorded. RESULTS: There was no significant difference between MDCT and CBCT within each group in the number of tumour foci >1 cm identified or size of the largest focus measured. MDCT had superior image quality compared to both CBCT groups (p<0.01), but CBCT demonstrated subsegmental branches more often in each group than MDCT. Both CBCT groups demonstrated higher CNR than MDCT (p<0.01). The dose-area product (3675±1295 versus 6598±1252 µGy·m2; p<0.001) and skin dose (119±41 versus 212±38 mGy; p<0.001) were significantly lower with 5-s CBCT than with 8-s CBCT. CONCLUSION: The relationship between MDCT and CBCT in both groups was consistent. The information obtained with 5-s CBCT was equivalent to that obtained with 8-s CBCT but with a lower radiation dose.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Tomografia Computadorizada de Feixe Cônico/métodos , Embolização Terapêutica/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Feminino , Humanos , Fígado/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Razão Sinal-Ruído , Resultado do Tratamento
13.
J Appl Microbiol ; 120(4): 921-33, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26808352

RESUMO

AIMS: In this study, the species indicator test was used to identify key bacterial taxa affected by changes in the soil environment as a result of conservation agriculture or conventional practices. METHODS AND RESULTS: Soils cultivated with wheat (Triticum spp. L.) and maize (Zea mays L.) under different raised bed planting systems for 20 years, that is, varying crop residue and fertilizer management, were used. Taxonomic- and divergence-based 16S-metagenomics, and IndVal analysis were used to study the bacterial communities and identify indicator taxa (genus and OTU97 ) affected by agricultural practices. Although, some phyla were affected significantly by different treatments, the taxonomic assemblages at phylum level were similar. Bacterial taxa related to different processes of the N-cycle were indicators of different fertilization rates, for example, Azorhizobium, Nostoc and Nitrosomonas. A large number of OTU97 were indicators for conventionally tilled beds and their distribution was defined by soil organic carbon. IndVal analysis identified different taxa in each of the residue management systems. This suggests that although the same organic material remains in the field, crop residue management affects specific taxa. The taxa indicator of the burned residues belonged mainly to the order SBR1031 (Anaerolineae, Chloroflexi), and the genera Bacillus and Alicyclobacillus. CONCLUSIONS: N-fertilizer application rates affected N-cycling taxa. Tillage affected Actinobacteria members and organic matter decomposers. Although the same crop residue was retained in the field, organic material management was important for specific taxa. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, we report that agricultural practice affected soil bacterial communities. We also identified distinctive taxa and related their distribution to changes in the soil environment resulting from different agricultural practices.


Assuntos
Agricultura/métodos , Bactérias/isolamento & purificação , Microbiologia do Solo , Triticum/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Fertilizantes/análise , Metagenômica , Filogenia , Solo/química
14.
Eur Heart J ; 36(25): 1590-600, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25904764

RESUMO

AIM: Constitutive genetic deletion of the adaptor protein p66(Shc) was shown to protect from ischaemia/reperfusion injury. Here, we aimed at understanding the molecular mechanisms underlying this effect in stroke and studied p66(Shc) gene regulation in human ischaemic stroke. METHODS AND RESULTS: Ischaemia/reperfusion brain injury was induced by performing a transient middle cerebral artery occlusion surgery on wild-type mice. After the ischaemic episode and upon reperfusion, small interfering RNA targeting p66(Shc) was injected intravenously. We observed that post-ischaemic p66(Shc) knockdown preserved blood-brain barrier integrity that resulted in improved stroke outcome, as identified by smaller lesion volumes, decreased neurological deficits, and increased survival. Experiments on primary human brain microvascular endothelial cells demonstrated that silencing of the adaptor protein p66(Shc) preserves claudin-5 protein levels during hypoxia/reoxygenation by reducing nicotinamide adenine dinucleotide phosphate oxidase activity and reactive oxygen species production. Further, we found that in peripheral blood monocytes of acute ischaemic stroke patients p66(Shc) gene expression is transiently increased and that this increase correlates with short-term neurological outcome. CONCLUSION: Post-ischaemic silencing of p66(Shc) upon reperfusion improves stroke outcome in mice while the expression of p66(Shc) gene correlates with short-term outcome in patients with ischaemic stroke.


Assuntos
Lesões Encefálicas/prevenção & controle , Inativação Gênica/fisiologia , Traumatismo por Reperfusão/prevenção & controle , Proteínas Adaptadoras da Sinalização Shc/genética , Acidente Vascular Cerebral/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Animais , Barreira Hematoencefálica/fisiologia , Estudos de Casos e Controles , Células Cultivadas , Claudina-5/efeitos dos fármacos , Células Endoteliais/fisiologia , Feminino , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Infarto da Artéria Cerebral Média , Pós-Condicionamento Isquêmico/métodos , Masculino , Camundongos Endogâmicos C57BL , Microcirculação/fisiologia , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Espécies Reativas de Oxigênio/farmacologia , Proteínas Adaptadoras da Sinalização Shc/fisiologia , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src , Resultado do Tratamento
15.
Psychol Med ; 45(13): 2861-71, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26004991

RESUMO

BACKGROUND: Cortical thickness measurement offers an index of brain development processes. In healthy individuals, cortical thickness is reduced with increasing age and is related to cognitive decline. Cortical thinning has been reported in schizophrenia. Whether cortical thickness changes differently over time in patients and its impact on outcome remain unanswered. METHOD: Data were examined from 109 patients and 76 healthy controls drawn from the Santander Longitudinal Study of first-episode schizophrenia for whom adequate structural magnetic resonance imaging (MRI) data were available (n = 555 scans). Clinical and cognitive assessments and MRIs were acquired at three regular time points during a 3-year follow-up period. We investigated likely progressive cortical thickness changes in schizophrenia during the first 3 years after initiating antipsychotic treatment. The effects of cortical thickness changes on cognitive and clinical variables were also examined along with the impact of potential confounding factors. RESULTS: There were significant diagnoses × scan time interaction main effects for total cortical thickness (F 1,309.1 = 4.60, p = 0.033) and frontal cortical thickness (F 1,310.6 = 5.30, p = 0.022), reflecting a lesser thinning over time in patients. Clinical and cognitive outcome was not associated with progressive cortical changes during the early years of the illness. CONCLUSIONS: Cortical thickness abnormalities do not unswervingly progress, at least throughout the first years of the illness. Previous studies have suggested that modifiable factors may partly account for cortical thickness abnormalities. Therefore, the importance of implementing practical actions that may modify those factors and improve them over the course of the illness should be highlighted.


Assuntos
Antipsicóticos/uso terapêutico , Transtornos Cognitivos/patologia , Lobo Frontal/patologia , Imageamento por Ressonância Magnética/métodos , Esquizofrenia/tratamento farmacológico , Esquizofrenia/patologia , Adolescente , Adulto , Estudos Transversais , Progressão da Doença , Feminino , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Espanha , Adulto Jovem
18.
Psychol Med ; 44(8): 1591-604, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24067252

RESUMO

BACKGROUND: Schizophrenia is a chronic brain disorder associated with structural brain abnormalities already present at the onset of the illness. Whether these brain abnormalities might progress over time is still under debate. METHOD: The aim of this study was to investigate likely progressive brain volume changes in schizophrenia during the first 3 years after initiating antipsychotic treatment. The study included 109 patients with a schizophrenia spectrum disorder and a control group of 76 healthy subjects. Subjects received detailed clinical and cognitive assessment and structural magnetic resonance imaging (MRI) at regular time points during a 3-year follow-up period. The effects of brain changes on cognitive and clinical variables were examined along with the impact of potential confounding factors. RESULTS: Overall, patients and healthy controls exhibited a similar pattern of brain volume changes. However, patients showed a significant lower progressive decrease in the volume of the caudate nucleus than control subjects (F 1,307.2 = 2.12, p = 0.035), with healthy subjects showing a greater reduction than patients during the follow-up period. Clinical and cognitive outcomes were not associated with progressive brain volume changes during the early years of the illness. CONCLUSIONS: Brain volume abnormalities that have been consistently observed at the onset of non-affective psychosis may not inevitably progress, at least over the first years of the illness. Taking together with clinical and cognitive longitudinal data, our findings, showing a lack of brain deterioration in a substantial number of individuals, suggest a less pessimistic and more reassuring perception of the illness.


Assuntos
Encéfalo/patologia , Progressão da Doença , Esquizofrenia/patologia , Adulto , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino
19.
J Fr Ophtalmol ; 47(7): 104236, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38880038

RESUMO

PURPOSE: To describe a surgical technique for functionally reconstructing a lacrimal drainage duct and to assess its long-term functionality. METHODS: This observational review includes six cases involving reconstruction of the inferior canaliculus after surgical resection of lower eyelid carcinoma. Following lesion excision with safety margins, the epithelium of the distal portion of the inferior canaliculus is located and intubated with a monocanalicular probe. Subsequently, the eyelid lamellae are reconstructed without displacing the probe. The Monoka collarette is then sutured using a 10/0 nylon suture. Data collection included anatomic pathology of the lesion and data from ophthalmic examinations at each visit (including epiphora, inferior canalicular irrigation, and fluorescein dye disappearance test [FDDT]), as well as stent extrusion or other complications. RESULTS: No complications were observed during the surgeries. The stents remained in place for an average of 4months, with no extrusions prior to removal. The mean follow-up period was 4.8years (SD=2.0), during which no other complications were noted. Only one patient experienced intermittent epiphora, also present in the fellow eye. At the final visit, FDDT was normal in all eyes, and all patients demonstrated patency of the inferior canaliculus upon irrigation. CONCLUSION: Primary reconstruction of an inferior lacrimal drainage duct following tumor resection can be successfully performed, resulting in favorable functional recovery.

20.
J Fr Ophtalmol ; 47(4): 104048, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38238142

RESUMO

PURPOSE: To describe a case report of a 34 years-old patient with Crohn's Disease and two episodes of Ocular Myositis. METHODS: The research methodology employed in this study consisted of a retrospective review of the patient's complete medical history. RESULTS: Crohn's Disease is a chronic inflammatory bowel disorder known to be associated with a wide range of extraintestinal manifestations. Ocular abnormalities, such as episcleritis and uveitis, are commonly observed. However, orbital myositis is an extremely rare ocular extraintestinal manifestations characterized by acute ocular pain that worsens with eye movements and is often accompanied by diplopia. In this case report, we present the case of a 34-year-old woman with a confirmed diagnosis of Crohn's Disease, who experienced two episodes of acute orbital pain exacerbated by ocular movements and diplopia. The diagnosis was established through clinical evaluation and radiologic imaging, with confirmation after a good response to systemic corticosteroids. She responded favorably to systemic corticosteroid therapy on both episodes, and no additional treatment was required. As of now, she remains stable without any ocular sequelae. CONCLUSION: It is important to note that orbital myositis is an uncommon ocular manifestation associated with Crohn's Disease, and prompt recognition and management are crucial to achieve successful outcomes.


Assuntos
Doença de Crohn , Miosite , Miosite Orbital , Feminino , Humanos , Adulto , Doença de Crohn/complicações , Doença de Crohn/diagnóstico , Doença de Crohn/tratamento farmacológico , Miosite Orbital/complicações , Miosite Orbital/diagnóstico , Diplopia/diagnóstico , Diplopia/etiologia , Dor/complicações
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