Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 189
Filtrar
1.
Endosc Int Open ; 11(8): E690-E696, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37564331

RESUMO

Background and study aim Simulator-based training has been extensively studied in training gastroduodenoscopy and colonoscopy and shown to significantly improve learning curves of novices. Data on simulator-based training in endoscopic retrograde cholangiopancreatography (ERCP) are scarce. We aimed to determine the impact of 2-day intensive hands-on simulator training on the course of the learning curve of novice trainees. Methods We conducted a prospective cohort study using a validated mechanical ERCP simulator (Boskoski-Costamagna ERCP Trainer). Six trainees were allocated to the simulation course program (SG). Each of these trainees were paired with an endoscopy trainee starting regular ERCP training at the same center who had no exposure to a simulation course program (control group; CG). The course included lectures, live ERCP demonstrations, and hands-on ERCP training to educate trainees in basic techniques related to cannulation, stent placement, stone extraction and stricture management. After the course, both the SG and CG started formal ERCP training in their respective centers. The Rotterdam Assessment Form for ERCP was used to register each performed ERCP. Simple moving average was applied to create learning curves based on successful common bile duct (CBD) cannulation. Outcomes were plotted against a historical cohort (HC). Results Thirteen trainees were included, six trainees in the SG and seven trainees in the CG, with a total of 717 ERCPs. Mean successful ERCP cannulation rate was higher for the simulator group at baseline compared to both CG and HC, 64% versus 43% and 42%, respectively. Differences became less explicit after 40 ERCPs, but persisted until a median of 75 ERCPs. Conclusions We demonstrate that 2-day hands-on simulator-based ERCP training course has a positive effect on the learning curves of ERCP trainees and should be considered an integral part of the training curricula for ERCP to develop skills prior to patient-based training.

2.
Adv Sci (Weinh) ; 10(19): e2301124, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37098646

RESUMO

The helicity of three-dimensional (3D) topological insulator surface states has drawn significant attention in spintronics owing to spin-momentum locking where the carriers' spin is oriented perpendicular to their momentum. This property can provide an efficient method to convert charge currents into spin currents, and vice-versa, through the Rashba-Edelstein effect. However, experimental signatures of these surface states to the spin-charge conversion are extremely difficult to disentangle from bulk state contributions. Here, spin- and angle-resolved photo-emission spectroscopy, and time-resolved THz emission spectroscopy are combined to categorically demonstrate that spin-charge conversion arises mainly from the surface state in Bi1 - x Sbx ultrathin films, down to few nanometers where confinement effects emerge. This large conversion efficiency is correlated, typically at the level of the bulk spin Hall effect from heavy metals, to the complex Fermi surface obtained from theoretical calculations of the inverse Rashba-Edelstein response. Both surface state robustness and sizeable conversion efficiency in epitaxial Bi1 - x Sbx thin films bring new perspectives for ultra-low power magnetic random-access memories and broadband THz generation.

3.
Endoscopy ; 55(1): 25-35, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35668651

RESUMO

BACKGROUND: Confirming the diagnosis, invasiveness, and disease extent of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas is challenging. The aim of this study was to summarize the literature on the efficacy and safety of peroral pancreatoscopy (POP) in the diagnosis of IPMN, including the impact of pre- and intraoperative POP on the management of IPMN. METHODS: The EMBASE, Medline Ovid, Web of Science, Cochrane CENTRAL, and Google Scholar databases were systematically searched for articles. Eligible articles investigated cohorts of patients who underwent POP for (suspected) IPMN. RESULTS: 25 articles were identified and included in this review; with 22 of these reporting on the diagnostic yield of POP in IPMN and 11 reporting on the effect of pre- or intraoperative POP on clinical decision-making. Cannulation and observation rates, and overall diagnostic accuracy were high across all studies. Frequently reported visual characteristics of IPMN were intraductal fish-egg-like lesions, hypervascularity, and granular mucosa. Overall, the adverse event rate was 12 %, primarily consisting of post-endoscopic retrograde cholangiopancreatography pancreatitis, with a pooled rate of 10 %, mostly of mild severity. Regarding the impact of POP on clinical decision-making, POP findings altered the surgical approach in 13 %-62 % of patients. CONCLUSION: POP is technically successful in the vast majority of patients with (suspected) IPMN, has a consistently high diagnostic accuracy, but an adverse event rate of 12 %. Data on intraoperative pancreatoscopy are scarce, but small studies suggest its use can alter surgical management. Future studies are needed to better define the role of POP in the diagnostic work-up of IPMN.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Císticas, Mucinosas e Serosas , Neoplasias Intraductais Pancreáticas , Neoplasias Pancreáticas , Humanos , Ductos Pancreáticos/cirurgia , Neoplasias Intraductais Pancreáticas/diagnóstico por imagem , Neoplasias Intraductais Pancreáticas/cirurgia , Neoplasias Pancreáticas/patologia , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Neoplasias Císticas, Mucinosas e Serosas/patologia , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/cirurgia , Carcinoma Ductal Pancreático/patologia , Estudos Retrospectivos
4.
J Hand Surg Asian Pac Vol ; 27(6): 935-944, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36476085

RESUMO

Background: To review the impact that arthroscopy has made on the assessment and treatment of intercarpal (scapholunate [SL] or lunotriquetral [LT]) ligament injuries associated with acute distal radius fractures (DRF). Methods: A systematic review of EMBASE, MEDLINE and COCHRANE databases for articles published between 2011 and 2021 was performed (PROSPERO ID: CRD42021273293) which included studies reported assessment and outcomes of intercarpal ligament injuries associated with acute DRF. Methodological quality was evaluated. The rate of concomitant injury detection, role of arthroscopy and different clinical outcome assessment measurements used were compared between studies. Results: A total of 20 articles were included with data from 1,346 patients (1,358 wrists). A total of 1,024 intra-articular fractures were included and 294 extra-articular fractures (40 not specified). There was a heterogeneous mix of studies; 10 comparative and 10 non-comparative. Some studies investigated initial assessment findings only, while others assessed radiological outcomes, functional outcomes or both domains over 0.3-99 months. The overall rate of SL ligament injury associated with DRF was 35.3%, while LT ligament injury overall was 18.2%. More frequent were concomitant triangular fibrocartilage complex (TFCC) injuries (44.8%), although this review did not aim to review these. The role of arthroscopy was reviewed, which included assistance in anatomic reduction of the articular surface and systematic inspection of the surrounding soft tissues. Included studies investigated either assessment or assessment and management of intercarpal ligament injury. Meaningful meta-analysis in this heterogeneous group of studies was not possible. Outcomes of comparative studies were described in detail. Conclusions: This review suggests that arthroscopy may have a role in improving reduction of intra-articular DRF and diagnosing and managing soft tissue injuries associated with such fractures. Randomised studies are needed to evaluate whether the detection of intercarpal ligament injury in acute distal radial fractures through arthroscopic assessment alters current management and improves clinical outcome. Level of Evidence: Level III (Therapeutic).


Assuntos
Fraturas do Rádio , Fraturas do Punho , Traumatismos do Punho , Humanos , Artroscopia , Ligamentos Articulares/cirurgia , Ligamentos Articulares/lesões , Fraturas do Rádio/diagnóstico por imagem , Fraturas do Rádio/cirurgia , Traumatismos do Punho/diagnóstico por imagem , Traumatismos do Punho/cirurgia
5.
Nanoscale ; 14(47): 17561-17570, 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36346287

RESUMO

Elucidating cellulose-lignin interactions at the molecular and nanometric scales is an important research topic with impacts on several pathways of biomass valorization. Here, the interaction forces between a cellulosic substrate and lignin are investigated. Atomic force microscopy with lignin-coated tips is employed to probe the site-specific adhesion to a cellulose film in liquid water. Over seven thousand force-curves are analyzed by a machine-learning approach to cluster the experimental data into types of cellulose-tip interactions. The molecular mechanisms for distinct types of cellulose-lignin interactions are revealed by molecular dynamics simulations of lignin globules interacting with different cellulose Iß crystal facets. This unique combination of experimental force-curves, data-driven analysis, and molecular simulations opens a new approach of investigation and updates the understanding of cellulose-lignin interactions at the nanoscale.


Assuntos
Celulose , Lignina , Microscopia de Força Atômica , Simulação de Dinâmica Molecular , Aprendizado de Máquina
6.
Appl Microbiol Biotechnol ; 106(11): 4075-4089, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35622124

RESUMO

Understanding the mechanisms involved in tolerance to inhibitors is the first step in developing robust yeasts for industrial second-generation ethanol (E2G) production. Here, we used ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) and MetaboAnalyst 4.0 for analysis of MS data to examine the changes in the metabolic profile of the yeast Spathaspora passalidarum during early fermentation of hemicellulosic hydrolysates containing high or low levels of inhibitors (referred to as control hydrolysate or CH and strategy hydrolysate or SH, respectively). During fermentation of SH, the maximum ethanol production was 16 g L-1 with a yield of 0.28 g g-1 and productivity of 0.22 g L-1 h-1, whereas maximum ethanol production in CH fermentation was 1.74 g L-1 with a yield of 0.11 g g-1 and productivity of 0.01 g L-1 h-1. The high level of inhibitors in CH induced complex physiological and biochemical responses related to stress tolerance in S. passalidarum. This yeast converted compounds with aldehyde groups (hydroxymethylfurfural, furfural, 4-hydroxybenzaldehyde, syringaldehyde, and vanillin) into less toxic compounds, and inhibitors were found to reduce cell viability and ethanol production. Intracellularly, high levels of inhibitors altered the energy homeostasis and redox balance, resulting in lower levels of ATP and NADPH, while that of glycolytic, pentose phosphate, and tricarboxylic acid (TCA) cycle pathways were the most affected, being the catabolism of glucogenic amino acids, the main cellular response to inhibitor-induced stress. This metabolomic investigation reveals interesting targets for metabolic engineering of ethanologenic yeast strains tolerant against multiple inhibitors for E2G production. KEY POINTS: • Inhibitors in the hydrolysates affected the yeast's redox balance and energy status. • Inhibitors altered the glycolytic, pentose phosphate, TCA cycle and amino acid pathways. • S. passalidarum converted aldehyde groups into less toxic compounds.


Assuntos
Saccharomyces cerevisiae , Xilose , Etanol/metabolismo , Fermentação , Fosfatos , Polissacarídeos , Saccharomyces cerevisiae/metabolismo , Saccharomycetales , Espectrometria de Massas em Tandem , Xilose/metabolismo
7.
Endosc Int Open ; 9(11): E1704-E1711, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34790534

RESUMO

Background and aims Indirect peroral cholangiopancreatoscopy (IPOC) is a relatively new diagnostic and therapeutic tool for biliopancreatic diseases. This international survey aimed to evaluate clinical practice patterns in IPOC among endoscopists in Europe. Methods An online survey was developed comprising 66 questions on the use of IPOC. Questions were grouped into four domains. The survey was sent to 369 endoscopists who perform IPOC. Results 86 respondents (23.3 %) from 21 different countries across Europe completed the survey. The main indications for cholangioscopy were determination of biliary strictures (85 [98.8 %]) and removal of common bile duct or intrahepatic duct stones (79 [91.9 %]), accounting for an estimated use of 40 % (interquartile range [IQR] 25-50) and 40 % (IQR 30-60), respectively, of all cases undergoing cholangioscopy. Pancreatoscopy was mainly used for removal of pancreatic duct stones (68/76 [89.5 %]), accounting for an estimated use of 76.5 % (IQR 50-95) of all cases undergoing pancreatoscopy. Only 13/85 respondents (15.3 %) had an institutional standardized protocol for targeted cholangioscopy-guided biopsy sampling. IPOC with lithotripsy was used as first-line treatment in selected patients with bile duct stones or pancreatic stones by 24/79 (30.4 %) and 53/68 (77.9 %) respondents, respectively. Conclusions This first European survey on the clinical practice of IPOC demonstrated wide variation in experience, indications, and techniques. These results emphasize the need for prospective studies and development of an international consensus guideline to standardize the practice and quality of IPOC.

8.
AJNR Am J Neuroradiol ; 42(10): 1870-1877, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34413061

RESUMO

BACKGROUND AND PURPOSE: Conventional MR imaging scoring is a valuable tool for risk stratification and prognostication of outcomes, but manual scoring is time-consuming, operator-dependent, and requires high-level expertise. This study aimed to automate the regional measurements of an established brain MR imaging scoring system for preterm neonates scanned between 29 and 47 weeks' postmenstrual age. MATERIALS AND METHODS: This study used T2WI from the longitudinal Prediction of PREterm Motor Outcomes cohort study and the developing Human Connectome Project. Measures of biparietal width, interhemispheric distance, callosal thickness, transcerebellar diameter, lateral ventricular diameter, and deep gray matter area were extracted manually (Prediction of PREterm Motor Outcomes study only) and automatically. Scans with poor quality, failure of automated analysis, or severe pathology were excluded. Agreement, reliability, and associations between manual and automated measures were assessed and compared against statistics for manual measures. Associations between measures with postmenstrual age, gestational age at birth, and birth weight were examined (Pearson correlation) in both cohorts. RESULTS: A total of 652 MRIs (86%) were suitable for analysis. Automated measures showed good-to-excellent agreement and good reliability with manual measures, except for interhemispheric distance at early MR imaging (scanned between 29 and 35 weeks, postmenstrual age; in line with poor manual reliability) and callosal thickness measures. All measures were positively associated with postmenstrual age (r = 0.11-0.94; R2 = 0.01-0.89). Negative and positive associations were found with gestational age at birth (r = -0.26-0.71; R2 = 0.05-0.52) and birth weight (r = -0.25-0.75; R2 = 0.06-0.56). Automated measures were successfully extracted for 80%-99% of suitable scans. CONCLUSIONS: Measures of brain injury and impaired brain growth can be automatically extracted from neonatal MR imaging, which could assist with clinical reporting.


Assuntos
Recém-Nascido Prematuro , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Estudos de Coortes , Humanos , Lactente , Recém-Nascido , Reprodutibilidade dos Testes
9.
Gastrointest Endosc ; 94(6): 1059-1068, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34216597

RESUMO

BACKGROUND AND AIMS: Digital single-operator cholangioscopy (d-SOC) with cholangioscopic biopsy sampling has shown promise in the evaluation of indeterminate biliary strictures. Some studies have suggested higher sensitivity for visual impression compared with biopsy sampling, although assessors were not blinded to previous investigations. We aimed to investigate the diagnostic accuracy and interobserver agreement (IOA) of d-SOC in the visual appraisal of biliary strictures when blinded to additional information. METHODS: A multicenter, international cohort study was performed. Cholangioscopic videos in patients with a known final diagnosis were systematically scored. Pseudonymized videos were reviewed by 19 experts in 2 steps: blinded for patient history and investigations and unblinded. RESULTS: Forty-four high-quality videos were reviewed of 19 benign and 25 malignant strictures. The sensitivity and specificity for the diagnosis of malignancy was 74.2% and 46.9% (blinded) and 72.7% and 62.5% (unblinded). Cholangioscopic certainty of a malignant diagnosis led to overdiagnosis (sensitivity, 90.6%; specificity, 33%), especially if no additional information was provided. The IOA for the presence of malignancy was fair for both assessments (Fleiss' κ = .245 [blinded] and κ = .321 [unblended]). For individual visual features, the IOA ranged from slight to moderate for both assessments (κ = .059-.400 vs κ = .031-.452). CONCLUSIONS: This study showed low sensitivity and specificity for blinded and unblinded d-SOC video appraisal of indeterminate biliary strictures, with considerable interobserver variation. Although reaching a consensus on the optical features of biliary strictures remains important, optimizing visually directed biopsy sampling may be the most important role of cholangioscopy in biliary stricture assessment.


Assuntos
Endoscopia do Sistema Digestório , Sobrediagnóstico , Estudos de Coortes , Constrição Patológica/etiologia , Humanos , Variações Dependentes do Observador
10.
Traffic Inj Prev ; 22(3): 242-245, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33661080

RESUMO

BACKGROUND: Electric scooters (e-scooters) are becoming increasingly common in major urban areas worldwide. Cities in some countries have even piloted programmes to promote their use to reduce general vehicular traffic. There have, however, been widespread media reports outlining concerns about their safety. We decided to investigate these concerns by reviewing the records of patients who presented to our center, a Level 1 Major Trauma Center in the United Kingdom, with orthopedic injuries associated with e-scooter use. METHODS: We reviewed the electronic medical records of all patients who presented to our center from January 2018 to January 2020 with e-scooter associated fractures. Demographic, injury, and surgical data were collected to characterize the types of e-scooter-related fractures and to investigate the frequency of such injuries over the duration of our search. A literature review of MEDLINE and EMBASE was performed to investigate specifically orthopedic injuries caused by electric scooter use. RESULTS: Six patients were identified (3 male, 3 female; mean age 35.43 years) who had sustained a variety of injuries. The presentation and clinical outcomes are presented. Three patients required operative management, and three patients were managed conservatively. CONCLUSION: This case series demonstrates an increasing frequency of significant orthopedic injury associated with e-scooter use treated at our center over the course of two years. This small series highlights an important problem given that this increase has occurred despite electric scooter usage in public spaces being illegal. Legalization might result in further increase in the incidence of injury.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Contusões/epidemiologia , Fraturas Ósseas/epidemiologia , Entorses e Distensões/epidemiologia , Adulto , Cidades/epidemiologia , Feminino , Dispositivos de Proteção da Cabeça/estatística & dados numéricos , Humanos , Masculino , Veículos Automotores , Estudos Retrospectivos , Fatores de Risco , Reino Unido , Adulto Jovem
12.
Br J Community Nurs ; 25(10): 480-488, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33030369

RESUMO

People with chronic pain faced potential treatment disruption during the COVID-19 pandemic in Singapore, as the focus of healthcare shifted. A model of rapid integration of a pain centre with community healthcare teams was implemented to care for vulnerable older patients with chronic pain and multiple comorbidities. Telemedicine and home visits by community nurses were used, with risk-mitigation measures, ensuring comprehensive assessment and treatment compliance. Medications from pain physicians were delivered at home through a hospital pharmacy. A secure national electronic health records system used by all teams ensured seamless access and documentation. Potential emergency department visits, admissions and delayed discharges were thus avoided. Integration of community teams with chronic pain management services can be recommended to ensure pandemic preparedness.


Assuntos
Dor Crônica/terapia , Enfermagem em Saúde Comunitária , Infecções por Coronavirus , Visita Domiciliar , Clínicas de Dor , Manejo da Dor , Pandemias , Pneumonia Viral , Telemedicina , Betacoronavirus , COVID-19 , Comportamento Cooperativo , Atenção à Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente , Encaminhamento e Consulta , SARS-CoV-2 , Singapura , Fluxo de Trabalho
15.
Phys Rev Lett ; 124(2): 027201, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-32004027

RESUMO

Relating magnetotransport properties to specific spin textures at surfaces or interfaces is an intense field of research nowadays. Here, we investigate the variation of the electrical resistance of Ge(111) grown epitaxially on semi-insulating Si(111) under the application of an external magnetic field. We find a magnetoresistance term that is linear in current density j and magnetic field B, hence, odd in j and B, corresponding to a unidirectional magnetoresistance. At 15 K, for I=10 µA (or j=0.33 A m^{-1}) and B=1 T, it represents 0.5% of the zero field resistance, a much higher value compared to previous reports on unidirectional magnetoresistance (UMR). We ascribe the origin of this magnetoresistance to the interplay between the externally applied magnetic field and the pseudomagnetic field generated by the current applied in the spin-splitted subsurface states of Ge(111). This unidirectional magnetoresistance is independent of the current direction with respect to the Ge crystal axes. It progressively vanishes, either using a negative gate voltage due to carrier activation into the bulk (without spin-splitted bands), or by increasing the temperature due to the Rashba energy splitting of the subsurface states lower than ∼58k_{B}. We believe that UMR could be used as a powerful probe of the spin-orbit interaction in a wide range of materials.

16.
Bioresour Technol ; 299: 122685, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31918970

RESUMO

Different pretreatments strategies have been developed over the years mainly to enhance enzymatic cellulose degradation. In the new biorefinery era, a more holistic view on pretreatment is required to secure optimal use of the whole biomass. Hydrothermal pretreatment technology is regarded as very promising for lignocellulose biomass fractionation biorefinery and to be implemented at the industrial scale for biorefineries of second generation and circular bioeconomy, since it does not require no chemical inputs other than liquid water or steam and heat. This review focuses on the fundamentals of hydrothermal pretreatment, structure changes of biomass during this pretreatment, multiproduct strategies in terms of biorefinery, reactor technology and engineering aspects from batch to continuous operation. The treatise includes a case study of hydrothermal biomass pretreatment at pilot plant scale and integrated process design.


Assuntos
Lignina , Vapor , Biomassa , Celulose , Fracionamento Químico , Engenharia , Hidrólise
19.
Int J Surg ; 56: 208-209, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29935369
20.
J Plast Reconstr Aesthet Surg ; 71(1): 21-27, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28917935

RESUMO

BACKGROUND: Reconstructive breast surgery has continued to evolve over the last decade with a key change being the adoption of acellular dermal matrices (ADMs) as an adjunct for implant-based procedures. This retrospective observational study assesses the effect of ADMs on post-mastectomy reconstructive practice performed in a single institution. METHODS: We conducted a review of all patients undergoing breast reconstruction at a University Teaching Hospital for an 18-month period before and after adopting ADMs. Demographic, procedural and complication data for these two cohorts were compared (χ2 and Student's t-tests). RESULTS: A total of 264 women (336 breasts), mean age 47.5 years, were identified: 137 before and 127 after the introduction of ADM. Implant-only reconstructions increased from 16% to 52% following the adoption of ADM (p < 0.01), whereas the proportion of both latissimus dorsi and deep inferior epigastric perforator flap reconstructions decreased significantly (31%-11% and 49%-34%, respectively, p < 0.01). The rate of early complications for the implant-only procedures was not significantly different with or without ADM (26% versus 20%, respectively, p = 0.44), despite there being no difference in the rate of adjuvant radiotherapy (22% versus 35%, respectively, p = 0.30). CONCLUSIONS: This study showed that since ADM introduction to our centre, more breast reconstructions have been of the implant-only type with consequent reductions in the more complex and expensive autologous techniques. Implant-only procedures that incorporated ADM use had similar complication rates to those that did not.


Assuntos
Derme Acelular/estatística & dados numéricos , Neoplasias da Mama/cirurgia , Mamoplastia/tendências , Mastectomia/métodos , Neoplasias da Mama/radioterapia , Feminino , Humanos , Pessoa de Meia-Idade , Retalho Perfurante , Radioterapia Adjuvante , Estudos Retrospectivos , Centros de Atenção Terciária , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...