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1.
Rev Sci Instrum ; 94(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38065173

RESUMO

Strain-controlled fully reversed fatigue testing, or strain-life testing, provides critical information on material lifetime and damage response. Strain-life data in hydrogen gas environments is missing in the literature and could provide valuable insights into hydrogen effects on the mechanical response of metals such as steel. We adapted existing hydrogen-gas-environment mechanical-testing equipment, which had been designed only for tensile loads, to accommodate the large compressive loads needed to perform strain-life testing. The considerations of these adaptations are discussed. Successful strain-life testing data were acquired from a 4130 pressure vessel steel.

2.
IDCases ; 31: e01725, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36923656

RESUMO

A 58-years-old male with history of previous aortic prosthetic endocarditis caused by Enterococcus faecalis was admitted due to dyspnoea and fever. The two sets of blood cultures were positive for Neisseria bacilliformis. Transoesophageal echocardiography did not demonstrate endocarditis signs, but PET-CT scan showed active infection signs in the valvular aortic tube and possible infection in the aortic prosthetic valve. A six-week course of ampicillin was prescribed; gentamicin was added during the first two weeks. The patient continued a favourable clinical course. This is the 3rd described case of N. bacilliformis endocarditis and the first one in a prosthetic valve.

3.
Biomed Pharmacother ; 158: 114070, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36526536

RESUMO

Stauprimide, a semi-synthetic derivative of staurosporine, is known mainly for its potent differentiation-enhancing properties in embryonic stem cells. Here, we studied the effects of stauprimide in cell growth and migration of triple-negative breast cancer cells in vitro, evaluating its potential antitumoral activity in an orthotopic mouse model of breast cancer in vivo. Our results from survival curves, EdU incorporation, cell cycle analysis and annexin-V detection in MDA-MB-231 cells indicated that stauprimide inhibited cell proliferation, arresting cell cycle in G2/M without induction of apoptosis. A decrease in the migratory capability of MDA-MB-231 was also assessed in response to stauprimide. In this work we pointed to a mechanism of action of stauprimide involving the modulation of ERK1/2, Akt and p38 MAPK signalling pathways, and the downregulation of MYC in MDA-MB-231 cells. In addition, orthotopic MDA-MB-231 xenograft and 4T1 syngeneic models suggested an effect of stauprimide in vivo, increasing the necrotic core of tumors and reducing metastasis in lung and liver of mice. Together, our results point to the promising role of stauprimide as a putative therapeutic agent in triple-negative breast cancer.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Feminino , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Ciclo Celular , Proliferação de Células , Neoplasias da Mama/tratamento farmacológico , Divisão Celular , Apoptose
4.
Clin Lab ; 68(9)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36125152

RESUMO

BACKGROUND: Proper identification of patients at risk of developing serious disease in the context of SARS-CoV-2 infection, as well as the initiation of early treatment, is one of the fundamental elements for successful management of COVID-19. The main objective of this study was to evaluate the usefulness of serum biomarkers (neutrophils, lymphocytes, C-reactive protein, lactate dehydrogenase, D-dimer, ferritin, and interleukin-6) to predict the early response to immunosuppressant therapy in COVID-19 patients. METHODS: This is a case-control study nested in a retrospective cohort, which included hospitalized patients with interstitial pneumonia and with elevation of some proinflammatory parameters. Each of the individuals who died during the 28-day follow-up was defined as a case. For each case, 4 controls were selected, matched by age, gender, and comorbidities. RESULTS: The initial cohort included 856 patients. The incidence of therapeutic failure in the cohort was 14%, thus we identified a total of 120 cases. After the application of a Cox regression model, high serum concentrations of LDH (> 451 IU/L), ferritin (> 1,014 ng/mL) and D-Dimer (> 1,300 ng/mL) were identified as predictors of poor response to treatment. Highly-specific cut-off points could not be established for any of these biomarkers. CONCLUSIONS: Some inflammatory biomarkers, such as LDH, ferritin, and D-dimer, may be helpful in identifying patients for whom an early immunomodulatory therapeutic intervention should be considered in the treatment of COVID-19 patients with pneumonia.


Assuntos
Tratamento Farmacológico da COVID-19 , Biomarcadores , Proteína C-Reativa/análise , Estudos de Casos e Controles , Ferritinas , Humanos , Fatores Imunológicos/uso terapêutico , Imunossupressores/uso terapêutico , Interleucina-6 , L-Lactato Desidrogenase , Estudos Retrospectivos , SARS-CoV-2
5.
Corros Sci ; 1822021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34267394

RESUMO

Coupon immersion tests were performed on 316L stainless steel in a simulated oilfield environment to evaluate the effect of H2S partial pressure on pit depth and density. Pitting was most significant at intermediate partial pressures of H2S, for which free H2S in the pit solution is maximised. Inhibition of pitting at higher partial pressures is attributed to blocking of the pit surface by metal sulphide phases. The key role of pH in the pit solution is to determine the solubility of metal sulphides and the availability of free H2S to adsorb on the reacting pit surface and sustain activity.

6.
Neuroimage ; 223: 117242, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32798678

RESUMO

In multisite neuroimaging studies there is often unwanted technical variation across scanners and sites. These "scanner effects" can hinder detection of biological features of interest, produce inconsistent results, and lead to spurious associations. We propose mica (multisite image harmonization by cumulative distribution function alignment), a tool to harmonize images taken on different scanners by identifying and removing within-subject scanner effects. Our goals in the present study were to (1) establish a method that removes scanner effects by leveraging multiple scans collected on the same subject, and, building on this, (2) develop a technique to quantify scanner effects in large multisite studies so these can be reduced as a preprocessing step. We illustrate scanner effects in a brain MRI study in which the same subject was measured twice on seven scanners, and assess our method's performance in a second study in which ten subjects were scanned on two machines. We found that unharmonized images were highly variable across site and scanner type, and our method effectively removed this variability by aligning intensity distributions. We further studied the ability to predict image harmonization results for a scan taken on an existing subject at a new site using cross-validation.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Algoritmos , Artefatos , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
7.
Mater Sci Eng C Mater Biol Appl ; 116: 111268, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32806245

RESUMO

Biocompatible and antibacterial multi-layer coatings of hydroxyapatite (HA)-Ag/SiO2/TiN/Ti were obtained on the Ti-6Al-4V alloy, by means of the magnetron sputtering technique. During characterization of the coatings, the chemical composition was evaluated by energy dispersive X-ray spectroscopy and the phase analysis was carried out by X-ray diffraction. The morphology of the coatings was observed by field emission scanning electron microscopy, while transmission electron microscopy was used to appreciate their structure. The adhesion of the coatings to the substrate was evaluated by micro scratch test. The in vitro biological response was evaluated in terms of cytotoxicity, adhesion and differentiation of mouse mesenchymal stem cells, as well as adhesion and bacterial viability of Staphylococcus aureus strain. Through the compositional study carried out, the deposition of the HA phase was verified, with a Ca/P ratio close to 1.67 and the characteristic diffraction peaks of this compound. The structural study of the coatings evidenced the obtention of multi-layer architectures. The use of an intermediate SiO2/TiN/Ti trilayer was found to improve adhesion between HA-Ag and the substrate by 84%. Finally, the in vitro biological tests carried out indicated a potentially non-toxic character in the coatings. Additionally, an antibacterial effect was registered at low concentrations of Ag (<0.25 mg/L).


Assuntos
Durapatita , Titânio , Animais , Camundongos , Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Teste de Materiais , Microscopia Eletrônica de Varredura , Dióxido de Silício , Prata/farmacologia , Titânio/farmacologia , Difração de Raios X
9.
Sci Immunol ; 4(42)2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31811055

RESUMO

Despite the importance of intestinal stem cells (ISCs) for epithelial maintenance, there is limited understanding of how immune-mediated damage affects ISCs and their niche. We found that stem cell compartment injury is a shared feature of both alloreactive and autoreactive intestinal immunopathology, reducing ISCs and impairing their recovery in T cell-mediated injury models. Although imaging revealed few T cells near the stem cell compartment in healthy mice, donor T cells infiltrating the intestinal mucosa after allogeneic bone marrow transplantation (BMT) primarily localized to the crypt region lamina propria. Further modeling with ex vivo epithelial cultures indicated ISC depletion and impaired human as well as murine organoid survival upon coculture with activated T cells, and screening of effector pathways identified interferon-γ (IFNγ) as a principal mediator of ISC compartment damage. IFNγ induced JAK1- and STAT1-dependent toxicity, initiating a proapoptotic gene expression program and stem cell death. BMT with IFNγ-deficient donor T cells, with recipients lacking the IFNγ receptor (IFNγR) specifically in the intestinal epithelium, and with pharmacologic inhibition of JAK signaling all resulted in protection of the stem cell compartment. In addition, epithelial cultures with Paneth cell-deficient organoids, IFNγR-deficient Paneth cells, IFNγR-deficient ISCs, and purified stem cell colonies all indicated direct targeting of the ISCs that was not dependent on injury to the Paneth cell niche. Dysregulated T cell activation and IFNγ production are thus potent mediators of ISC injury, and blockade of JAK/STAT signaling within target tissue stem cells can prevent this T cell-mediated pathology.


Assuntos
Interferon gama/imunologia , Mucosa Intestinal/citologia , Mucosa Intestinal/imunologia , Células-Tronco/imunologia , Linfócitos T/imunologia , Animais , Morte Celular , Mucosa Intestinal/patologia , Camundongos
11.
J Healthc Qual Res ; 34(4): 209-216, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31713532

RESUMO

INTRODUCTION: the main aim of this study was to develop and implement a risk map in the Oral and Maxillofacial Surgery Service of the University Hospital «Virgen de las Nieves¼ of Granada to minimize the incidence of adverse effects (AE). MATERIALS AND METHODS: Longitudinal, prospective study carried out in the Oral and Maxillofacial Surgery Service of the Hospital Universitario Virgen de las Nieves of Granada, from June 2017 to May 2018, through the methodology of «Analysis and Failure Mode Effect¼. Management of the different AE was addressed. The following phases were considered as it follows: identification of the problem, identification of AE for within the practice of the oral and maxillofacial surgery that represents a problem in the assistive safety, creation of an interdisciplinary working group, analysis of the current situation in patient safety and risk management using 2analysis tools, SWOT and PITELO, preparation of the patient care process, development of a catalog of AE and preparation of a risk map. RESULTS: A total of 33 AE were identified. The risk map showed a higher incidence of AE in the Surgical Area (22) compared to the areas of Outpatient Clinic and Hospital Discharge (6). A total of 10 critical AE were identified. CONCLUSIONS: The elaboration of a risk map allowed to determine the process of the oral and maxillofacial surgical patient, and to elaborate a catalog of AE.


Assuntos
Procedimentos Cirúrgicos Bucais/efeitos adversos , Segurança do Paciente , Gestão de Riscos/organização & administração , Cirurgia Bucal , Unidades Hospitalares , Humanos , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos , Medição de Risco/métodos , Gestão de Riscos/métodos
15.
Enferm Intensiva (Engl Ed) ; 30(2): 78-91, 2019.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29903540

RESUMO

OBJECTIVE: Analyze the role of the nurse at the end of the life of a critically ill patient. METHOD: Bibliographic review from a search of the health science databases such as PubMed, CINAHL, Cuiden, Scopus, Cochrane, as well as specialized platforms, general and thematic browsers. The limits were language (English or Spanish) and publication date (2005-2015). RESULTS: 180 articles met the inclusion criteria, and 16 of them were selected for analysis. The main results were grouped into three categories of analysis: direct patient care, family-focussed care and the nurse's role within the team. CONCLUSIONS: the described roles place the nurse as a key element in humanising death in the ICU and so nurses can and must lead change, playing an active role in creating strategies that really promote the integration of a palliative care approach in ICU.


Assuntos
Estado Terminal/enfermagem , Papel do Profissional de Enfermagem , Assistência Terminal , Humanos
16.
Eng Fract Mech ; 2162019.
Artigo em Inglês | MEDLINE | ID: mdl-32165761

RESUMO

Strain-life testing of a 4130 pressure vessel steel was conducted in hydrogen gas through the careful adaptation of an existing hydrogen-gas mechanical-testing apparatus. The strain-life mechanical results reveal that hydrogen has a significant effect on the strain-life, and impacts both the elastic and plastic responses of the material. Microscopy analysis shows a distinct difference in the microstructural development of the material after cyclic loading in air compared to after loading in hydrogen gas. These experimental results will inform coupled damage and deformation modeling.

17.
J Healthc Qual Res ; 33(5): 256-263, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-30361103

RESUMO

INTRODUCTION: Patient safety in oral and maxillofacial surgery is oriented towards providing patient care by means of adequate risk management that minimises adverse events and fosters a culture of safe clinical practices as the fundamental basis of quality health care. To implement preventive actions are implemented in order to improve patient safety and to reduce the incidence of adverse events, as well as to improve the quality of care. The aim of this report is to implement preventive measures in order to improve the health care of the patient in an Oral and Maxillofacial Surgery Unit by reducing the Adverse Events and proving good quality healthcare. MATERIALS AND METHODS: A longitudinal, prospective, single centre study was conducted using a methodology of analysis of modes of failure and effects of the management of potentially serious adverse events in the Oral and Maxillofacial surgical unit of the University Hospital of Granada (June-November 2017), as well as the preparation and implementation of a series of corrective measures. RESULTS: A total of 33 adverse events were recorded, with 10 of them considered as critical, distributed in different areas of care, and referred from Primary Health Care and from other hospitals. Seven preventive actions were implemented: information to the patient, training actions, improvements in the protocols and procedures, in the care process and clinical practice, as well as the need to set up an adequate checklist, and other miscellaneous. DISCUSSION: The implementation of preventive measures represent a notable advance in the prevention of harm to the patient and the organisation, involving healthcare staff in a safety culture oriented towards quality care.


Assuntos
Erros Médicos/prevenção & controle , Procedimentos Cirúrgicos Bucais/efeitos adversos , Segurança do Paciente , Complicações Pós-Operatórias/prevenção & controle , Qualidade da Assistência à Saúde , Lista de Checagem , Humanos , Procedimentos Cirúrgicos Bucais/normas , Sistemas de Identificação de Pacientes , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Gestão de Riscos/organização & administração
20.
AJNR Am J Neuroradiol ; 39(10): 1806-1813, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30213803

RESUMO

BACKGROUND AND PURPOSE: The central vein sign is a promising MR imaging diagnostic biomarker for multiple sclerosis. Recent studies have demonstrated that patients with MS have higher proportions of white matter lesions with the central vein sign compared with those with diseases that mimic MS on MR imaging. However, the clinical application of the central vein sign as a biomarker is limited by interrater differences in the adjudication of the central vein sign as well as the time burden required for the determination of the central vein sign for each lesion in a patient's full MR imaging scan. In this study, we present an automated technique for the detection of the central vein sign in white matter lesions. MATERIALS AND METHODS: Using multimodal MR imaging, the proposed method derives a central vein sign probability, πij, for each lesion, as well as a patient-level central vein sign biomarker, ψi. The method is probabilistic in nature, allows site-specific lesion segmentation methods, and is potentially robust to intersite variability. The proposed algorithm was tested on imaging acquired at the University of Vermont in 16 participants who have MS and 15 participants who do not. RESULTS: By means of the proposed automated technique, participants with MS were found to have significantly higher values of ψ than those without MS (ψMS = 0.55 ± 0.18; ψnon-MS = 0.31 ± 0.12; P < .001). The algorithm was also found to show strong discriminative ability between patients with and without MS, with an area under the curve of 0.88. CONCLUSIONS: The current study presents the first fully automated method for detecting the central vein sign in white matter lesions and demonstrates promising performance in a sample of patients with and without MS.


Assuntos
Algoritmos , Esclerose Múltipla/diagnóstico por imagem , Neuroimagem/métodos , Veias/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Veias/patologia , Substância Branca/patologia
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