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1.
Int Microbiol ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483746

RESUMO

The indiscriminate use of petroleum-based polymers and plastics for single-use food packaging has led to serious environmental problems due the non-biodegradable characteristics. Thus, much attention has been focused on the research of new biobased and biodegradable materials. Yeast and fungal biomass are low-cost and abundant sources of biopolymers with highly promising properties for the development of biodegradable materials. This study aimed to select a preparation method to develop new biodegradable films using the whole biomass of Paecilomyces variotii subjected to successive physical treatments including ultrasonic homogenization (US) and heat treatment. Sterilization process had an important impact on the final filmogenic dispersion and mechanical properties of the films. Longer US treatments produced a reduction in the particle size and the application of an intermediate UT treatment contributed favorably to the breaking of agglomerates allowing the second US treatment to be more effective, achieving an ordered network with a more uniform distribution. Samples that were not filtrated after the sterilization process presented mechanical properties similar to plasticized materials. On the other hand, the filtration process after sterilization eliminated soluble and hydratable compounds, which produced a reduction in the hydration of the films.

2.
Ear Hear ; 45(2): 400-410, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37828657

RESUMO

OBJECTIVES: Commercially available auditory steady state response (ASSR) systems are widely used to obtain hearing thresholds in the pediatric population objectively. Children are often examined during natural or induced sleep so that the recorded ASSRs are of subcortical origin, the inferior colliculus being often designated as the main ASSR contributor in these conditions. This report presents data from a battery of auditory neurophysiological objective tests obtained in 3 cases of severe brainstem dysfunction in sleeping children. In addition to ASSRs, envelope-following response (EFR) recordings designed to distinguish peripheral (cochlear nerve) from central (brainstem) were recorded to document the effect of brainstem dysfunction on the two types of phase-locked responses. DESIGN: Results obtained in the 3 children with severe brainstem dysfunctions were compared with those of age-matched controls. The cases were identified as posterior fossa tumor, undiagnosed (UD), and Pelizaeus-Merzbacher-Like Disease. The standard audiological objective tests comprised tympanograms, distortion product otoacoustic emissions, click-evoked auditory brainstem responses (ABRs), and ASSRs. EFRs were recorded using horizontal (EFR-H) and vertical (EFR-V) channels and a stimulus phase rotation technique allowing isolation of the EFR waveforms in the time domain to obtain direct latency measurements. RESULTS: The brainstem dysfunctions of the 3 children were revealed as abnormal (weak, absent, or delayed) ABRs central waves with a normal wave I. In addition, they all presented a summating and cochlear microphonic potential in their ABRs, coupled with a normal wave I, which implies normal cochlear and cochlear nerve function. EFR-H and EFR-V waveforms were identified in the two cases in whom they were recorded. The EFR-Hs onset latencies, response durations, and phase-locking values did not differ from their respective age-matched control values, indicating normal cochlear nerve EFRs. In contrast, the EFR-V phase-locking value and onset latency varied from their control values. Both patients had abnormal but identifiable and significantly phase-locked brainstem EFRs, even in a case with severely distorted ABR central waves. ASSR objective audiograms were recorded in two cases. They showed normal or slightly elevated (explained by a slight transmission loss) thresholds that do not yield any clue about their brainstem dysfunction, revealing the method's lack of sensitivity to severe brainstem dysfunction. CONCLUSIONS: The present study, performed on 3 sleeping children with severe brainstem dysfunction but normal cochlear responses (cochlear microphonic potential, summating potential, and ABR wave I), revealed the differential sensitivity of three auditory electrophysiological techniques. Estimated thresholds obtained by standard ASSR recordings (cases UD and Pelizaeus-Merzbacher-Like Disease) provided no clue to the brainstem dysfunction clearly revealed by the click-evoked ABR. EFR recordings (cases posterior fossa tumor and UD) showed preserved central responses with abnormal latencies and low phase-locking values, whereas the peripheral EFR attributed to the cochlear nerve was normal. The one case (UD) for which the three techniques could be performed confirms this sensitivity gradient, emphasizing the need for applying the Cross-Check Principle by avoiding resorting to ASSR recording alone. The entirely normal EFR-H recordings observed in two cases further strengthen the hypothesis of its cochlear nerve origin in sleeping children.


Assuntos
Potenciais Evocados Auditivos do Tronco Encefálico , Neoplasias Infratentoriais , Humanos , Criança , Limiar Auditivo/fisiologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Audição/fisiologia , Tronco Encefálico , Estimulação Acústica
3.
Cell Tissue Bank ; 21(4): 557-562, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33063150

RESUMO

On March 19 World Health Organization declare the pandemic situation by outbreak coronavirus disease 2019 in the world. The pressure on the health care system has been very high in several countries. Spanish National Transplant Organization (ONT) have made many efforts in maintaining transplantation activity. Although the impact of the pandemic on organ activity has been analysed, to date, less data exist regarding the impact on tissue activity. The aim of this study has been the evaluation of the possible impact on the procurement, processing and distribution of tissues during the peak period of the pandemic COVID-19 in Spain. For this study, a multicentre analysis has been made with a survey of the tissue banks in Spain, during the period March 1 to April 30, 2020. Our data suggest that the impact of coronavirus in Spain has affected dramatically tissue donation but with a moderate effect on stored tissues such as bone, valves, vessels or skin. Tissue banks should prepare if future next pandemic waves surges so that tissue provision is guaranteed both in urgent and elective surgeries.


Assuntos
Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Bancos de Tecidos/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , Transplante/estatística & dados numéricos , Betacoronavirus , COVID-19 , Humanos , Pandemias , SARS-CoV-2 , Espanha/epidemiologia , Inquéritos e Questionários
4.
Sensors (Basel) ; 19(21)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683559

RESUMO

Optical Coherence Tomography Angiography (OCTA) constitutes a new non-invasive ophthalmic image modality that allows the precise visualization of the micro-retinal vascularity that is commonly used to analyze the foveal region. Given that there are many systemic and eye diseases that affect the eye fundus and its vascularity, the analysis of that region is crucial to diagnose and estimate the vision loss. The Visual Acuity (VA) is typically measured manually, implying an exhaustive and time-consuming procedure. In this work, we propose a method that exploits the information of the OCTA images to automatically estimate the VA with an accurate error of 0.1713.


Assuntos
Angiografia/métodos , Biomarcadores/análise , Vasos Sanguíneos/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Acuidade Visual/fisiologia , Algoritmos , Automação , Fóvea Central/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Análise de Componente Principal , Reprodutibilidade dos Testes
5.
Mar Pollut Bull ; 198: 115907, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38061147

RESUMO

Anthropogenic noise is a pollutant of global concern. While the effects of underwater noise pollution have been frequently studied in fish and mammals, our understanding of how this anthropogenic stressor affects marine reptiles is scant. Using a multichannel data logger equipped with a camera and hydrophone, we quantified behavioural responses of a free-ranging green turtle (Chelonia mydas) to vessel noise in the Galapagos Archipelago, an important nesting site in the eastern Pacific. We found that while travelling the turtle increased its vigilance with increasing vessel noise. However, when on the seabed the turtle did not increase its vigilance with increasing noise levels. Our findings illustrate that noise pollution has the potential to alter overall time budgets of animals. Identifying real-time responses of wild animals illustrate how in situ approaches allow to assess the effects of human activities on marine systems.


Assuntos
Ruído , Tartarugas , Humanos , Animais , Tartarugas/fisiologia , Peixes , Animais Selvagens , Atividades Humanas , Mamíferos
6.
Biosensors (Basel) ; 12(11)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36354500

RESUMO

Millions of workers are required to wear reusable respirators in several industries worldwide. Reusable respirators include filters that protect workers against harmful dust, smoke, gases, and vapors. These hazards may cause cancer, lung impairment, and diseases. Respiratory protection is prone to failure or misuse, such as wearing respirators with filters out of service life and employees wearing respirators loosely. Currently, there are no commercial systems capable of reliably alerting of misuse of respiratory protective equipment during the workday shifts or provide early information about dangerous clogging levels of filters. This paper proposes a low energy and non-obtrusive functional building block with embedded electronics that enable breathing monitoring inside an industrial reusable respirator. The embedded electronic device collects multidimensional data from an integrated pressure, temperature, and relative humidity sensor inside a reusable industrial respirator in real time and sends it wirelessly to an external platform for further processing. Here, the calculation of instantaneous breathing rate and estimation of the filter's respirator fitting and clogging level is performed. The device was tested with ten healthy subjects in laboratory trials. The subjects were asked to wear industrial reusable respirator with the embedded electronic device attached inside. The signals measured with the system were compared with airflow signals measured with calibrated transducers for validation purposes. The correlation between the estimated breathing rates using pressure, temperature, and relative humidity with the reference signal (airflow) is 0.987, 0.988 and 0.989 respectively, showing that instantaneous breathing rate can be calculated accurately using the information from the embedded device. Moreover, respirator fitting (well-fitted or loose condition) and filter's clogging levels (≤60%, 80% and 100% clogging) also can be estimated using features extracted from absolute pressure measurements combined to statistical analysis ANOVA models. These experimental outputs represent promising results for further development of data-driven prediction models using machine learning techniques to determine filters end-of-service life. Furthermore, the proposed system would collect relevant data for real-time monitoring of workers' breathing conditions and respirator usage, helping to improve occupational safety and health in the workplace.


Assuntos
Dispositivos de Proteção Respiratória , Humanos , Gases , Respiração , Eletrônica
7.
Food Sci Technol Int ; 28(6): 502-513, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34151621

RESUMO

Sensory analysis for stuffed cheese with Penicillium nalgiovense superficial growth using a descriptive analysis was performed. Cheeses were manufactured in a pilot plant. Penicillium nalgiovense was superficially inoculated and the cheeses were ripened at 12 °C and 90% relative humidity until packaged using a microperforated polyethylene film on day 14. The ripening process continued at either 5 °C or 12 °C for 21 days. Results showed that P. nalgiovense not only confers the external desirable appearance but also has a protective effect against dehydration process. Inoculated cheeses showed descriptors of odour and flavour associated with moulds. Ammonia notes were perceived only for inoculated cheeses on day 35 being more pronounced at 12 °C than 5 °C. The high fat content of the cheeses and the transparent and microperforated packaging might affect the oxidative stability of cheeses at the end of the ripening.


Assuntos
Queijo , Penicillium , Amônia , Queijo/análise , Polietilenos
8.
PLoS One ; 14(2): e0212364, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30794594

RESUMO

Angiography by Optical Coherence Tomography (OCT-A) is a non-invasive retinal imaging modality of recent appearance that allows the visualization of the vascular structure at predefined depths based on the detection of the blood movement through the retinal vasculature. In this way, OCT-A images constitute a suitable scenario to analyze the retinal vascular properties of regions of interest as is the case of the macular area, measuring the characteristics of the foveal vascular and avascular zones. Extracted parameters of this region can be used as prognostic factors that determine if the patient suffers from certain pathologies (such as diabetic retinopathy or retinal vein occlusion, among others), indicating the associated pathological degree. The manual extraction of these biomedical parameters is a long, tedious and subjective process, introducing a significant intra and inter-expert variability, which penalizes the utility of the measurements. In addition, the absence of tools that automatically facilitate these calculations encourages the creation of computer-aided diagnosis frameworks that ease the doctor's work, increasing their productivity and making viable the use of this type of vascular biomarkers. In this work we propose a fully automatic system that identifies and precisely segments the region of the foveal avascular zone (FAZ) using a novel ophthalmological image modality as is OCT-A. The system combines different image processing techniques to firstly identify the region where the FAZ is contained and, secondly, proceed with the extraction of its precise contour. The system was validated using a representative set of 213 healthy and diabetic OCT-A images, providing accurate results with the best correlation with the manual measurements of two experts clinician of 0.93 as well as a Jaccard's index of 0.82 of the best experimental case in the experiments with healthy OCT-A images. The method also provided satisfactory results in diabetic OCT-A images, with a best correlation coefficient with the manual labeling of an expert clinician of 0.93 and a Jaccard's index of 0.83. This tool provides an accurate FAZ measurement with the desired objectivity and reproducibility, being very useful for the analysis of relevant vascular diseases through the study of the retinal micro-circulation.


Assuntos
Retinopatia Diabética/diagnóstico , Fóvea Central/patologia , Processamento de Imagem Assistida por Computador/métodos , Tomografia de Coerência Óptica/métodos , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Retinopatia Diabética/diagnóstico por imagem , Feminino , Fóvea Central/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Oftalmologia , Prognóstico , Adulto Jovem
9.
J Clin Med ; 8(10)2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31547127

RESUMO

The assessment of vascular biomarkers and their correlation with visual acuity is one of the most important issues in the diagnosis and follow-up of retinal vein occlusions (RVOs). The high workloads of clinical practice make it necessary to have a fast, objective, and automatic method to analyze image features and correlate them with visual function. The aim of this study is to propose a fully automatic system which is capable of estimating visual acuity (VA) in RVO eyes, based only on information obtained from macular optical coherence tomography angiography (OCTA) images. We also propose an automatic methodology to rapidly measure the foveal avascular zone (FAZ) area and the vascular density (VD) in the superficial and deep capillary plexuses in swept-source OCTA images centered on the fovea. The proposed methodology is validated using a representative sample of 133 visits of 50 RVO patients. Our methodology estimates VA with very high precision and is even more accurate when we integrate depth information, providing a high correlation index of 0.869 with the real VA, which outperforms the correlation index of 0.855 obtained when estimating VA from the data obtained by the semiautomatic existing method. In conclusion, the proposed method is the first computational system able to estimate VA in RVO, with the additional benefits of being automatic, less time-consuming, objective and more accurate. Furthermore, the proposed method is able to integrate depth information, a feature which is lacking in the existing method.

10.
Int J Cardiol ; 290: 15-20, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31130280

RESUMO

BACKGROUND: Growth differentiation factor 15 (GDF-15) is a marker of cell senescence. Age is a well-known determinant of GDF-15 levels, yet no study has analyzed the relationship between geriatric conditions and GDF-15. We hypothesize that geriatric conditions reflecting biological age might be stronger determinants of GDF-15 than chronological age in elderly patients with acute coronary syndrome. METHODS: A total of 208 patients (mean age = 78.3 ±â€¯7.0 years) were included. Prior to discharge, a thorough geriatric assessment was performed and GDF-15 measured. Predictors of GDF-15 (transformed by its natural logarithm) were determined with linear regression. Furthermore, Cox regression was used for the analysis of all-cause mortality. The median follow-up was 728 days. RESULTS: Median GDF-15 concentration was 2432 pg/ml. In multivariate analysis, frailty (Fried score, p = 0.001), and comorbidity (Charlson index, p = 0.003) were independent determinants of lnGDF-15 while age was not significant (p = 0.17). Other covariates included in the model were male gender (p = 0.017), diabetes (p = 0.169), Killip class ≥2 (p = 0.046) and glomerular filtration rate (p = 0.001). The Fried score and Charlson index provided significant incremental value in the R2 model (0.362 vs 0.447; p = 0.0001). A total of 66 (32%) patients died. LnGDF-15 was a significant mortality predictor (HR = 1.82, 95% CI 1.12-2.94, p = 0.015) along with the Fried score (p = 0.013) and the Charlson index (p = 0.030). CONCLUSIONS: Geriatric conditions are strong determinants of GDF-15 levels on top of age in acute coronary syndromes. Furthermore, GDF-15 was associated with mortality independently of geriatric status. Geriatric assessment and GDF-15 are complementary tools.


Assuntos
Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/diagnóstico , Avaliação Geriátrica/métodos , Fator 15 de Diferenciação de Crescimento/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Alta do Paciente/tendências
11.
Front Physiol ; 9: 464, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867527

RESUMO

Considerable advances have been made toward understanding the cellular and molecular mechanism of wound healing, however, treatments for chronic wounds remain elusive. Emerging concepts utilizing mesenchymal stem cells (MSCs) from umbilical cord, adipose tissue and bone marrow have shown therapeutical advantages for wound healing. Based on this positive outcome, efforts to determine the optimal sources for MSCs are required in order to improve their migratory, angiogenic, immunomodulatory, and reparative abilities. An alternative source suitable for repetitive, non-invasive collection of MSCs is from the menstrual fluid (MenSCs), displaying a major practical advantage over other sources. This study aims to compare the biological functions and the transcriptomic pattern of MenSCs with umbilical cord MSCs in conditions resembling the wound microenvironment. Consequently, we correlate the specific gene expression signature from MenSCs with changes of the wound matrix signals in vivo. The direct comparison revealed a superior clonogenic and migratory potential of MenSCs as well as a beneficial effect of their secretome on human dermal fibroblast migration in vitro. Furthermore, MenSCs showed increased immunomodulatory properties, inhibiting T-cell proliferation in co-culture. We further, investigated the expression of selected genes involved in wound repair (growth factors, cytokines, chemokines, AMPs, MMPs) and found considerably higher expression levels in MenSCs (ANGPT1 1.5-fold; PDGFA 1.8-fold; PDGFB 791-fold; MMP3 21.6-fold; ELN 13.4-fold; and MMP10 9.2-fold). This difference became more pronounced under a pro-inflammatory stimulation, resembling wound bed conditions. Locally applied in a murine excisional wound splinting model, MenSCs showed a significantly improved wound closure after 14 days, as well as enhanced neovascularization, compared to the untreated group. Interestingly, analysis of excised wound tissue revealed a significantly higher expression of VEGF (1.42-fold) among other factors, translating an important conversion of the matrix signals in the wound site. Furthermore, histological analysis of the wound tissue from MenSCs-treated group displayed a more mature robust vascular network and a genuinely higher collagen content confirming the pro-angiogenic and reparative effect of MenSCs treatment. In conclusion, the superior clonogenicity, immunosuppressive and migration potential in combination with specific paracrine signature of MenSCs, resulted in an enhanced wound healing and cutaneous regeneration process.

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