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1.
Immunity ; 53(4): 852-863.e7, 2020 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-32976769

RESUMEN

Influenza B virus (IBV) infections can cause severe disease in children and the elderly. Commonly used antivirals have lower clinical effectiveness against IBV compared to influenza A viruses (IAV). Neuraminidase (NA), the second major surface protein on the influenza virus, is emerging as a target of broadly protective antibodies that recognize the NA active site of IAVs. However, similarly broadly protective antibodies against IBV NA have not been identified. Here, we isolated and characterized human monoclonal antibodies (mAbs) that target IBV NA from an IBV-infected patient. Two mAbs displayed broad and potent capacity to inhibit IBV NA enzymatic activity, neutralize the virus in vitro, and protect against lethal IBV infection in mice in prophylactic and therapeutic settings. These mAbs inserted long CDR-H3 loops into the NA active site, engaging residues highly conserved among IBV NAs. These mAbs provide a blueprint for the development of improved vaccines and therapeutics against IBVs.


Asunto(s)
Anticuerpos Antivirales/inmunología , Dominio Catalítico/inmunología , Virus de la Influenza B/inmunología , Neuraminidasa/inmunología , Proteínas Virales/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Línea Celular , Perros , Femenino , Células HEK293 , Humanos , Virus de la Influenza A/inmunología , Gripe Humana/inmunología , Leucocitos Mononucleares/inmunología , Células de Riñón Canino Madin Darby , Ratones , Ratones Endogámicos BALB C , Persona de Mediana Edad , Infecciones por Orthomyxoviridae/inmunología
2.
Nature ; 622(7983): 471-475, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37758953

RESUMEN

Resonant oscillators with stable frequencies and large quality factors help us to keep track of time with high precision. Examples range from quartz crystal oscillators in wristwatches to atomic oscillators in atomic clocks, which are, at present, our most precise time measurement devices1. The search for more stable and convenient reference oscillators is continuing2-6. Nuclear oscillators are better than atomic oscillators because of their naturally higher quality factors and higher resilience against external perturbations7-9. One of the most promising cases is an ultra-narrow nuclear resonance transition in 45Sc between the ground state and the 12.4-keV isomeric state with a long lifetime of 0.47 s (ref. 10). The scientific potential of 45Sc was realized long ago, but applications require 45Sc resonant excitation, which in turn requires accelerator-driven, high-brightness X-ray sources11 that have become available only recently. Here we report on resonant X-ray excitation of the 45Sc isomeric state by irradiation of Sc-metal foil with 12.4-keV photon pulses from a state-of-the-art X-ray free-electron laser and subsequent detection of nuclear decay products. Simultaneously, the transition energy was determined as [Formula: see text] with an uncertainty that is two orders of magnitude smaller than the previously known values. These advancements enable the application of this isomer in extreme metrology, nuclear clock technology, ultra-high-precision spectroscopy and similar applications.

3.
Nature ; 570(7761): 385-389, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31142840

RESUMEN

Cell-free DNA in the blood provides a non-invasive diagnostic avenue for patients with cancer1. However, characteristics of the origins and molecular features of cell-free DNA are poorly understood. Here we developed an approach to evaluate fragmentation patterns of cell-free DNA across the genome, and found that profiles of healthy individuals reflected nucleosomal patterns of white blood cells, whereas patients with cancer had altered fragmentation profiles. We used this method to analyse the fragmentation profiles of 236 patients with breast, colorectal, lung, ovarian, pancreatic, gastric or bile duct cancer and 245 healthy individuals. A machine learning model that incorporated genome-wide fragmentation features had sensitivities of detection ranging from 57% to more than 99% among the seven cancer types at 98% specificity, with an overall area under the curve value of 0.94. Fragmentation profiles could be used to identify the tissue of origin of the cancers to a limited number of sites in 75% of cases. Combining our approach with mutation-based cell-free DNA analyses detected 91% of patients with cancer. The results of these analyses highlight important properties of cell-free DNA and provide a proof-of-principle approach for the screening, early detection and monitoring of human cancer.


Asunto(s)
ADN Tumoral Circulante/sangre , ADN Tumoral Circulante/genética , Fragmentación del ADN , Genoma Humano/genética , Neoplasias/diagnóstico , Neoplasias/genética , Estudios de Casos y Controles , Estudios de Cohortes , Análisis Mutacional de ADN , Humanos , Aprendizaje Automático , Mutación , Neoplasias/sangre , Neoplasias/patología
4.
J Synchrotron Radiat ; 31(Pt 3): 596-604, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38587894

RESUMEN

The Materials Imaging and Dynamics (MID) instrument at the European X-ray Free-Electron Laser Facility (EuXFEL) is equipped with a multipurpose diagnostic end-station (DES) at the end of the instrument. The imager unit in DES is a key tool for aligning the beam to a standard trajectory and for adjusting optical elements such as focusing lenses or the split-and-delay line. Furthermore, the DES features a bent-diamond-crystal spectrometer to disperse the spectrum of the direct beam to a line detector. This enables pulse-resolved characterization of the EuXFEL spectrum to provide X-ray energy calibration, and the spectrometer is particularly useful in commissioning special modes of the accelerator. Together with diamond-based intensity monitors, the imager and spectrometer form the DES unit which also contains a heavy-duty beamstop at the end of the MID instrument. Here, we describe the setup in detail and provide exemplary beam diagnostic results.

5.
Phys Rev Lett ; 132(20): 206102, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38829060

RESUMEN

The liquid-to-solid phase transition is a complex process that is difficult to investigate experimentally with sufficient spatial and temporal resolution. A key aspect of the transition is the formation of a critical seed of the crystalline phase in a supercooled liquid, that is, a liquid in a metastable state below the melting temperature. This stochastic process is commonly described within the framework of classical nucleation theory, but accurate tests of the theory in atomic and molecular liquids are challenging. Here, we employ femtosecond x-ray diffraction from microscopic liquid jets to study crystal nucleation in supercooled liquids of the rare gases argon and krypton. Our results provide stringent limits to the validity of classical nucleation theory in atomic liquids, and offer the long-sought possibility of testing nonclassical extensions of the theory.

6.
Phys Rev Lett ; 130(17): 173201, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37172237

RESUMEN

We demonstrate that x-ray fluorescence emission, which cannot maintain a stationary interference pattern, can be used to obtain images of structures by recording photon-photon correlations in the manner of the stellar intensity interferometry of Hanbury Brown and Twiss. This is achieved utilizing femtosecond-duration pulses of a hard x-ray free-electron laser to generate the emission in exposures comparable to the coherence time of the fluorescence. Iterative phasing of the photon correlation map generated a model-free real-space image of the structure of the emitters. Since fluorescence can dominate coherent scattering, this may enable imaging uncrystallised macromolecules.

7.
Colorectal Dis ; 25(1): 31-43, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36031925

RESUMEN

AIM: To (1) develop an assessment tool for laparoscopic complete mesocolic excision (LCME) and (2) report evidence of its content validity. METHOD: Assessment statements were revealed through (1) semi-structured expert interviews and (2) consensus by the Delphi method, both involving an expert panel of five LCME surgeons. All experts were interviewed and then asked to rate LCME describing statements from 1 (strongly disagree) to 5 (strongly agree). Responses were returned anonymously to the panel until consensus was reached. Statements were directly included as content in the assessment tool if ≥60% of the experts responded "agree" or "strongly agree" (ratings 4 and 5), with the remaining responses being "neither agree nor disagree" (rating 3). Interclass correlation coefficient (ICC) was calculated for expert agreement evaluation. All included statements were subsequently reformulated as tool items and approved by the experts. RESULTS: Four Delphi rounds were performed to reach consensus. Disagreement was reported for statements describing instrument handling around pancreas; visualisation of landmarks before inferior mesenteric artery ligation; lymphadenectomy around the inferior mesenteric artery, and division of the terminal ileum and transverse colon. ICC in the last Delphi-round was 0.84. The final tool content included 73 statements, converted to 48 right- and 40 left-sided items for LCME assessment. CONCLUSION: A procedure-specific, video-based tool, named complete mesocolic excision competency assessment tool (CMECAT), has been developed for LCME skill assessment. In the future, we hope it can facilitate assessment of LCME surgeons, resulting in improved patient outcome after colon cancer surgery.


Asunto(s)
Colon Transverso , Neoplasias del Colon , Laparoscopía , Humanos , Laparoscopía/métodos , Neoplasias del Colon/cirugía , Colon Transverso/cirugía , Escisión del Ganglio Linfático/métodos , Ligadura , Técnica Delphi
8.
Colorectal Dis ; 25(11): 2139-2146, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37776110

RESUMEN

AIM: The complete mesocolic excision competency assessment tool (CMECAT) is a novel tool designed to assess technical skills in minimally invasive complete mesocolic excision (CME) surgery. The aim of this study was to assess construct validity and reliability of CMECAT in a clinical context. METHOD: Colorectal surgeons were asked to submit video recorded laparoscopic CME resections for independent assessment of their technical abilities. The videos were grouped by surgeons' training level, and four established CME experts were recruited as CMECAT assessors. Extended reliability analysis (G-theory) was applied to describe assessor agreement. RESULTS: A total of 19 videos and 72 assessments were included in the analysis. Overall, technical skills assessed by CMECAT improved with increased training level: the experts scored significantly better than the untrained surgeons (3.3 vs. 2.5 points; p < 0.01). On right-sided resections, significantly higher scores were reported with increased training level for all categories and sections, while for left-sided resections, the variance across groups was smaller and significantly higher scores were only reported for oncological safety describing items. Overall, assessor agreement was high (G-coefficient: 0.81). CONCLUSION: This study confirms that CMECAT can be applied to video recorded CME cases for technical skill assessment. Further, it can reliably assess technical performance in right sided CME surgery, where construct validity has now been established. More videos are required to evaluate its validity on left colonic CME. In the future, we hope CMECAT can improve feedback during CME training, serve as a tool in certification processes and contribute to distinguishing CME from conventional surgery in future research.


Asunto(s)
Neoplasias del Colon , Laparoscopía , Mesocolon , Humanos , Escisión del Ganglio Linfático , Neoplasias del Colon/cirugía , Reproducibilidad de los Resultados , Mesocolon/cirugía , Colectomía , Resultado del Tratamiento
9.
Proc Natl Acad Sci U S A ; 117(39): 24110-24116, 2020 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-32934145

RESUMEN

Dynamics and kinetics in soft matter physics, biology, and nanoscience frequently occur on fast (sub)microsecond but not ultrafast timescales which are difficult to probe experimentally. The European X-ray Free-Electron Laser (European XFEL), a megahertz hard X-ray Free-Electron Laser source, enables such experiments via taking series of diffraction patterns at repetition rates of up to 4.5 MHz. Here, we demonstrate X-ray photon correlation spectroscopy (XPCS) with submicrosecond time resolution of soft matter samples at the European XFEL. We show that the XFEL driven by a superconducting accelerator provides unprecedented beam stability within a pulse train. We performed microsecond sequential XPCS experiments probing equilibrium and nonequilibrium diffusion dynamics in water. We find nonlinear heating on microsecond timescales with dynamics beyond hot Brownian motion and superheated water states persisting up to 100 µs at high fluences. At short times up to 20 µs we observe that the dynamics do not obey the Stokes-Einstein predictions.

10.
Eur Surg Res ; 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38061337

RESUMEN

INTRODUCTION: Healing is essential for successful colorectal surgery. Optimal microcirculation is needed to ensure this; however, this is only subjectively assessed by the surgeon. Laser Speckle Contrast Imaging (LSCI) is an objective non-contact, image-based method to quantify microcirculation in bowel ends. This study aimed to evaluate the application of LSCI in an open surgery porcine model, determine differences between normal and impaired microcirculation, and test the LSCI applicability to repeated measurements. METHOD: A midline laparotomy was made in ten healthy female pigs to expose the colon and small intestine. Subsequently, baseline measurements were conducted. A local arteria supplying the colonic or small intestine mesentery was clamped for 5 min. and LSCI measures were made again. After an hour's rest, LSCI measurements were done in two unaffected areas on the colon and the small intestine, and baseline values were recorded. Hypotension was induced with rapid bleeding and LSCI measurements were done. After the mean arterial blood pressure (MAP) dropped to 50-60 mmHg, norepinephrine infusion was started. At a stable MAP of 85-100 mmHg, LSCI measurements were repeated at 0 min. and 30 min. during continuous norepinephrine infusion. RESULTS: Cross-clamping caused LSCI levels to drop equally in both the colon and small intestine by 60% in the entire the clamped zone. Compared to baseline, the microcirculation measured by LSCI in the unclamped adjacent transition zone was diminished by 33% and 40%, colon and small intestines, respectively. During hypotension due to bleeding, LSCI decreased as expected. When MAP was stabilized by norepinephrine infusion, LSCI values dropped further: compared to baseline, measurements decreased with 24% and 20% in colon and small intestines, respectively. CONCLUSION: LSCI can be used as a quantitative, real-time, non-contact method to detect changes in the microcirculation during open intestinal surgery with large changes in microcirculation due to e.g., hypovolemic and norepinephrine infusion. It is simple to use and in contrast to the existing intraoperative microcirculation assessment techniques, LSCI stands out primarily for its elimination of the requirement for a dye. As our study has shown, this feature allows us to perform time-independent measurements and repeat them indefinitely in nearby regions without compromising the effectiveness of the method.

11.
Mol Pharm ; 19(5): 1598-1603, 2022 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-35451842

RESUMEN

Dissolution of solid matter into aqueous solution is one of the most challenging physicochemical aspects related to drug development. While influenced by several parameters, the effect of pH remains the most important one to be fully understood. The dissolution process is essentially controlled by activity at the surface of the molecular crystals, which is difficult to characterize experimentally. To address this, a combination of in situ atomic force microscopy (AFM) with molecular dynamics (MD) simulation is reported. AFM allows for direct visualization of the crystal surface of basic and acidic model compounds (carvedilol and ibuprofen) in contact with an aqueous medium with varying pH. A dramatic increase in surface mobility in the solid-liquid interface could be observed experimentally as a function of pH. The in situ AFM approach opens up for a more detailed understanding of the behavior of particulate matter in solution with importance at different levels, ranging from engineering aspects related to crystallization, and biological considerations related to bioavailability of the final drug product.


Asunto(s)
Agua , Disponibilidad Biológica , Cristalización , Concentración de Iones de Hidrógeno , Microscopía de Fuerza Atómica , Agua/química
12.
Scand J Gastroenterol ; 57(2): 246-252, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34735311

RESUMEN

OBJECTIVE AND AIMS: The primary aim of this study was to evaluate the correlation between incidental focal colorectal foci on fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) with colonoscopic and histopathological results. The secondary aim was to determine to what extent these findings led to a change in patient management. MATERIALS AND METHODS: A retrospective study was performed among 5850 patients who had an FDG-PT/CT scan from July 2015 to July 2018. Among these patients, we identified patients with a PET/CT description of incidental colorectal FDG uptake, and a colonoscopy within 90 days from the PET/CT scan. PET/CT findings were compared with colonoscopy-detected lesions and eventually histopathology on a per-lesion analysis and a per-person analysis. RESULTS: A total of 145 patients were included in the study. A total of 180 foci of colorectal FDG uptake were detected on FDG-PET/CT. Of these, 86 foci corresponded to advanced colorectal neoplasia (ACRN), positive predictive value (PPV) 47.8%; 95% CI: 40.5-55.1%). On a per-patient analysis 81 patients had a least one ACRN at colonoscopy (PPV 55.9%; 95% CI: 47.6-63.8), this group included 20 patients (13.8%) diagnosed with cancer. There was a small positive correlation between focal FDG-uptake and the finding of ACRN at the same colonic segment at colonoscopy, which was statistically significant, rho = 0.2565, p = .002. The findings changed patient management in 67 (46.2%) cases. CONCLUSIONS: Incidental focal colorectal FDG uptake on PET/CT is associated with a high risk of ACRN and is affecting subsequent patient management. Further evaluation with colonoscopy is recommended when the patient is considered suitable for further treatment.


Asunto(s)
Neoplasias Colorrectales , Fluorodesoxiglucosa F18 , Colonoscopía/métodos , Neoplasias Colorrectales/diagnóstico por imagen , Neoplasias Colorrectales/patología , Humanos , Hallazgos Incidentales , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Tomografía de Emisión de Positrones , Radiofármacos , Estudios Retrospectivos
13.
Int J Colorectal Dis ; 37(5): 1161-1172, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35469107

RESUMEN

PURPOSE: Anastomotic leakage (AL) continues to be a challenge after restorative rectal resection (RRR). Various treatment options of AL are available; however, their long-term outcomes are uncertain. We explored the impact of AL on the risk of stoma presence 1 year after RRR for rectal cancer and described treatment of AL after RRR including impact on the probability of receiving adjuvant chemotherapy and stoma presence following different treatment options of AL. METHODS: We included 859 patients undergoing RRR in Central Denmark Region between 2013 and 2019. Stoma presence was calculated as the proportion of patients with stoma 1 year after RRR. Multivariable logistic regression was conducted to estimate the impact of AL on stoma presence adjusting for potential predictors. Descriptive data of outcomes were stratified for various treatment options of AL. RESULTS: The risk of stoma presence 1 year after surgery was 9.8% (95% CI 7.98-12.0). Predictors for having stoma 1 year after RRR were AL (OR 8.43 (95% CI 4.87-14.59)) and low tumour height (OR 3.85 (95% CI 1.22-13.21)). For patients eligible for adjuvant chemotherapy, the probability of receiving it was 42.9% (95% CI 21.8-66.0) if treated with endo-SPONGE and 71.4% (95% CI 47.8-88.7) if treated with other anastomosis preserving treatment options. The risk of having stoma 1 year after RRR was 33.9% (95% CI 21.8-47.8) for patients treated with endo-SPONGE and 13.5% (95% CI 5.6-25.8) for patients treated with other anastomosis preserving treatment options (p = 0.013). CONCLUSION: AL is a strong predictor for stoma presence 1 year after RRR. Patients treated with endo-SPONGE seem to have worse outcomes compared to other anastomosis preserving treatment options.


Asunto(s)
Proctectomía , Neoplasias del Recto , Estomas Quirúrgicos , Anastomosis Quirúrgica/efectos adversos , Fuga Anastomótica/cirugía , Fuga Anastomótica/terapia , Humanos , Neoplasias del Recto/patología , Estudios Retrospectivos , Factores de Riesgo , Estomas Quirúrgicos/efectos adversos , Estomas Quirúrgicos/patología
14.
Int J Colorectal Dis ; 37(6): 1335-1348, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35538165

RESUMEN

PURPOSE: The aim of this study was to evaluate the anastomotic leakage (AL) rate and predictors for AL following minimally invasive restorative rectal resection (RRR) among rectal cancer patients managed according to up-to-date standardized treatment. Furthermore, we explored the impact of symptomatic AL on long-term survival. METHODS: The study cohort was rectal cancer patients undergoing minimally invasive RRR in Central Denmark Region between 2013 and 2017. Data was retrieved from a prospective clinical quality database and supplemented with data from medical records. The AL rate was calculated as the proportion of patients who developed symptomatic AL within 30 days. Predictors for AL were identified through logistic regression. The impact of AL on long-term survival was analyzed using Kaplan-Meier methods and Cox regression. RESULTS: AL occurred in 15.1% of 604 patients. The AL rate for males was 20.1% (95% CI 16.3-24.3) and 5.0% (95% CI 2.4-9.0) for females. Odds ratio (OR) of AL in females vs. males was 0.25 (95% CI 0.12-0.51). The use of at least three firings when transecting the rectum was associated with OR of 2.71 (95% CI 1.17-6.26) for AL. The 5-year survival for patients with vs. those without AL was 76.1% (95%CI 65.1-84.0) and 83.6% (95%CI 79.8-86.7), corresponding to adjusted hazard ratio of 1.43 (95%CI 0.84-2.41). CONCLUSION: Symptomatic AL is still a challenge in a standardized setting using minimally invasive surgery in rectal cancer patients undergoing RRR, especially in men. Multiple firings should be avoided in transection of the rectum with an endoscopic stapler. AL had a statistical non-significant negative impact on survival.


Asunto(s)
Fuga Anastomótica , Neoplasias del Recto , Anastomosis Quirúrgica , Fuga Anastomótica/cirugía , Femenino , Humanos , Masculino , Estudios Prospectivos , Neoplasias del Recto/cirugía , Recto/cirugía , Estudios Retrospectivos , Factores de Riesgo
15.
Surg Endosc ; 36(9): 1-9, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35141776

RESUMEN

BACKGROUND: Adenoma detection rate (ADR) is the single most important measure of quality in colonoscopy, but little is known about the detection rate of serrated lesions (SLDR). To improve ADR, Endocuff Vision (EV) can be used. Studies have shown differing results as to the effect on ADR; an effect on SLDR has not been shown. To investigate the effect of Endocuff Vision on ADR in a screening population, this randomized controlled open label trial with concealed allocation was performed. Randomization to trial group was carried out by the endoscopist using prepared numbered envelopes. METHODS: Patients referred as part of the national bowel screening program at Regional Hospital Herning, Denmark were recruited and allocated to one of two groups: Endocuff Vision colonoscopy (EVC) and standard colonoscopy (SC). Outcomes were ADR, mean number, site, and size of lesions per procedure. SLDR as outcome was added after inclusion had begun. RESULTS: A total of 1178 participants were included, with 1166 (EVC 583 and SC 583) available for analysis. There was no clinical relevant difference in ADR (59.2% [CI 55.1; 63.1] v 60.5% [CI 56.5; 64.4]) or SLDR (13.0% [CI 10.5; 16.0] v 10.3% [CI 8.0; 13.0]) between groups. More serrated lesions were found per procedure (MSP) (0.2 v 0.1, IRR 57% [CI 17; 109]. Removal rate of EV was similar in the two study groups. CONCLUSION: We found no significant effects of the use of Endocuff Vision on ADR, when compared to standard colonoscopy, but more serrated lesions were detected in the Endocuff group. TRIAL REGISTRATION: Clinical Trials NCT04651062.


Asunto(s)
Adenoma , Pólipos del Colon , Neoplasias Colorrectales , Adenoma/diagnóstico , Adenoma/patología , Pólipos del Colon/diagnóstico por imagen , Colonoscopios , Colonoscopía/métodos , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/patología , Detección Precoz del Cáncer/métodos , Humanos , Tamizaje Masivo
16.
Surg Endosc ; 36(3): 1761-1774, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34873653

RESUMEN

BACKGROUND: In laparoscopic colorectal surgery, higher technical skills have been associated with improved patient outcome. With the growing interest in laparoscopic techniques, pressure on surgeons and certifying bodies is mounting to ensure that operative procedures are performed safely and efficiently. The aim of the present review was to comprehensively identify tools for skill assessment in laparoscopic colon surgery and to assess their validity as reported in the literature. METHODS: A systematic search was conducted in EMBASE and PubMed/MEDLINE in May 2021 to identify studies examining technical skills assessment tools in laparoscopic colon surgery. Available information on validity evidence (content, response process, internal structure, relation to other variables, and consequences) was evaluated for all included tools. RESULTS: Fourteen assessment tools were identified, of which most were procedure-specific and video-based. Most tools reported moderate validity evidence. Commonly not reported were rater training, assessment correlation with variables other than training level, and validity reproducibility and reliability in external educational settings. CONCLUSION: The results of this review show that several tools are available for evaluation of laparoscopic colon cancer surgery, but few authors present substantial validity for tool development and use. As we move towards the implementation of new techniques in laparoscopic colon surgery, it is imperative to establish validity before surgical skill assessment tools can be applied to new procedures and settings. Therefore, future studies ought to examine different aspects of tool validity, especially correlation with other variables, such as patient morbidity and pathological reports, which impact patient survival.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo , Laparoscopía , Competencia Clínica , Colon/cirugía , Humanos , Laparoscopía/métodos , Reproducibilidad de los Resultados
17.
Surg Endosc ; 36(1): 47-56, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33398569

RESUMEN

BACKGROUND: The efficacy of simulation-based training in surgical education is well known. However, the development of training programs should start with problem identification and a general needs assessment to ensure that the content is aligned with current surgical trainee needs. The objective of the present study is to identify the technical skills and clinical procedures that should be included in a simulation-based curriculum in general surgery. METHODS: A national, three-round Delphi process was conducted to achieve consensus on which technical skills and clinical procedures should be included in a simulation-based curriculum in general surgery. In total, 87 key opinion leaders were identified and invited to the study. RESULTS: Round 1 of the Delphi process had a response rate of 64% (56/87) and a total of 245 suggestions. Based on these suggestions, a consolidated list of 51 technical skills or clinical procedures was made. The response rate in Delphi round 2 was 62% (54/87) resulting in a pre-prioritized order of procedures for round 3. The response rate in Delphi round 3 was 65% (35/54). The final list included 13 technical skills and clinical procedures. Training was predominantly requested within general open surgical skills, laparoscopic skills, and endoscopic skills, and a few specific procedures such as appendectomy and cholecystectomy were included in the final prioritized list. CONCLUSION: Based on the Delphi process 13 technical skills and clinical procedures were included in the final prioritized list, which can serve as a point of departure when developing simulation-based training in surgery.


Asunto(s)
Cirugía General , Internado y Residencia , Entrenamiento Simulado , Competencia Clínica , Simulación por Computador , Curriculum , Técnica Delphi , Humanos , Evaluación de Necesidades , Entrenamiento Simulado/métodos
18.
Biotechnol Appl Biochem ; 69(1): 7-19, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33179313

RESUMEN

Enzymatic biodiesel production has been at the forefront of biofuels research in recent decades because of the significant environmental advantages it offers, while having the potential to be as effective as conventional chemically catalyzed biodiesel production. However, the higher capital cost, longer reaction time, and sensitivity of enzyme processes have restricted their widespread industrial adoption so far. It is also posited that the lack of research to bring the biodiesel product into final specification has scuppered industrial confidence in the viability of the enzymatic process. Furthermore, the vast majority of literature has focused on the development of immobilized enzyme processes, which seem too costly (and risky) to be used industrially. There has been little focus on liquid lipase formulations such as the Eversa Transform 2.0, which is in fact already used commercially for triglyceride transesterification. It is the objective of this review to highlight new research that focuses on bringing enzymatically produced biodiesel into specification via a liquid lipase polishing process, and the process considerations that come with it.


Asunto(s)
Biocombustibles , Lipasa , Biotecnología , Enzimas Inmovilizadas/metabolismo , Esterificación , Lipasa/metabolismo
19.
BMC Surg ; 22(1): 360, 2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36229822

RESUMEN

BACKGROUND: Despite increasing focus on the technical performance of total mesorectal excision over recent decades, anastomotic leakage (AL) continues to be a serious complication for many patients, even in the hands of experienced surgical teams. This study describes implementation of standardized surgical technique in an effort to reduce variability, decrease the risk of anastomotic leakage, and improve associated short-term outcomes for rectal cancer patients undergoing robot-assisted restorative rectal resection (RRR). METHODS: We evaluated all rectal cancer patients undergoing robot-assisted RRR at Aarhus University Hospital between 2017 and 2020. Six standardized surgical steps directed to improve anastomotic healing were mandatory for all RRR. Additional changes were made during the period with prohibition of systemic dexamethasone and limiting the use of endoscopic stapling devices. RESULTS: The use of the full standardization, including all six surgical steps, increased from 40.3% (95% CI, 0.28-0.54) to 86.2% (95% CI, 0.68-0.95). The incidence of AL decreased from 21.0% (95% CI, 0.12-0.33) to 6.9% (95% CI, 0.01-0.23). Length of hospital stay (LOS) decreased from 6 days (range 2-50) to 5 days (range 2-26). The rate of patients readmitted within 90 days decreased from 21.0% (95% CI, 0.12-0.33), to 6.9% (95% CI, 0.01-0.23). CONCLUSION: The full standardization was effectively implemented for rectal cancer patients undergoing robot-assisted RRR. The risk of AL, LOS and readmission decreased during the study period. A team focus on high-reliability and peri-operative complications can improve patient outcomes.


Asunto(s)
Neoplasias del Recto , Robótica , Fuga Anastomótica , Estudios de Cohortes , Dexametasona , Humanos , Neoplasias del Recto/cirugía , Reproducibilidad de los Resultados , Estudios Retrospectivos
20.
Entropy (Basel) ; 24(5)2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35626497

RESUMEN

In a traditional distributed storage system, a source can be restored perfectly when a certain subset of servers is contacted. The coding is independent of the contents of the source. This paper considers instead a lossy source coding version of this problem where the more servers that are contacted, the higher the quality of the restored source. An example could be video stored on distributed storage. In information theory, this is called the multiple description problem, where the distortion depends on the number of descriptions received. The problem considered in this paper is how to restore the system operation when one of the servers fail and a new server replaces it, that is, repair. The requirement is that the distortions in the restored system should be no more than in the original system. The question is how many extra bits are needed for repair. We find an achievable rate and show that this is optimal in certain cases. One conclusion is that it is necessary to design the multiple description codes with repair in mind; just using an existing multiple description code results in unnecessary high repair rates.

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