Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 55
Filter
1.
Nano Lett ; 24(27): 8296-8302, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38920284

ABSTRACT

Chirality is inherent to a broad range of systems, including solid-state and wave physics. The precession (chiral motion) of the magnetic moments in magnetic materials, forming spin waves, has various properties and many applications in magnetism and spintronics. We show that an optical analogue of spin waves can be generated in arrays of plasmonic nanohelices. Such optical waves arise from the interaction between twisted helix eigenmodes carrying spin and orbital angular momenta. We demonstrate that these optical spin waves are reflected at the interface between successive domains of enantiomeric nanohelices, forming a heterochiral lattice regardless of the wave propagation direction within the lattice. Optical spin waves may be applied in techniques involving photon spin, ranging from data processing and storage to quantum optics.

2.
Article in English | MEDLINE | ID: mdl-37660283

ABSTRACT

BACKGROUND: Bone fragility fractures are associated with high morbidity and mortality. This study analysed the association between the current biochemical parameters of CKD-MBD and bone fragility fractures in the COSMOS project. METHODS: COSMOS is a 3-year, multicentre, open cohort, prospective, observational study carried out in 6797 hemodialysis patients (227 centres from 20 European countries). The association of bone fragility fractures (outcome) with serum calcium, phosphate and PTH (exposure), was assessed using Standard Cox proportional hazards regression and Cox proportional hazards regression for recurrent events. Additional analyses were performed considering all-cause mortality as a competitive event for bone fragility fracture occurrence. Multivariable models were used in all strategies, with the fully adjusted model including a total of 24 variables. RESULTS: During a median follow-up of 24 months 252 (4%) patients experienced at least one bone fragility fracture (incident bone fragility fracture rate 28.5 per 1000 patient-years). In the fractured and non-fractured patients, the percentage of men was 43.7% and 61.4%, mean age 68.1 and 63.8 years and a haemodialysis vintage of 55.9 and 38.3 months respectively. Baseline serum phosphate > 6.1 mg/dL (reference value 4.3-6.1 mg/dL) was significantly associated with a higher bone fragility fracture risk in both regression models (HR: 1.53[95%CI: 1.10-2.13] and HR: 1.44[95%CI: 1.02-2.05]. The significant association persisted after competitive risk analysis (subHR: 1.42[95%CI: 1.02-1.98]) but the finding was not confirmed when serum phosphate was considered as a continuous variable. Baseline serum calcium showed no association with bone fragility fracture risk in any regression model. Baseline serum PTH > 800 pg/mL was significantly associated with a higher bone fragility fracture risk in both regression models, but the association disappeared after a competitive risk analysis. CONCLUSIONS: Hyperphosphatemia was independently and consistently associated with an increased bone fracture risk, suggesting serum phosphate could be a novel risk factor for bone fractures in hemodialysis patients.

3.
Med Phys ; 50(11): 7192-7202, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37738612

ABSTRACT

BACKGROUND: In vivo dosimetry (IVD) is gaining interest for treatment delivery verification in HDR-brachytherapy. Time resolved methods, including source tracking, have the ability both to detect treatment errors in real time and to minimize experimental uncertainties. Multiprobe IVD architectures holds promise for simultaneous dose determinations at the targeted tumor and surrounding healthy tissues while enhancing measurement accuracy. However, most of the multiprobe dosimeters developed so far either suffer from compactness issues or rely on complex data post-treatment. PURPOSE: We introduce a novel concept of a compact multiprobe scintillator detector and demonstrate its applicability in HDR-brachytherapy. Our fabricated seven-fiber probing system is sufficiently narrow to be inserted in a brachytherapy needle or in a catheter. METHODS: Our multiprobe detection system results from the parallel implementation of six miniaturized inorganic Gd2 O2 S:Tb scintillator detectors at the end of a bundle of seven fibers, one fiber is kept bare to assess the stem effect. The resulting system, which is narrower than 320 microns, is tested with a MicroSelectron 9.14 Ci Ir-192 HDR afterloader, in a water phantom. The detection signals from all six probes are simultaneously read with a sCMOS camera (at a rate of 0.06 s). The camera is coupled to a chromatic filter to cancel Cerenkov signal induced within the fibers upon exposure. By implementing an aperiodic array of six scintillating cells along the bundle axis, we first determine the range of inter-probe spacings leading to optimal source tracking accuracy (first tracking method). Then, three different source tracking algorithms involving all the scintillating probes are tested and compared. In each of these four methods, dwell positions are assessed from dose measurements and compared to the treatment plan. Dwell time is also determined and compared to the treatment plan. RESULTS: The optimum inter-probe spacing for an accurate source tracking ranges from 15 to 35 mm. The optimum detection algorithm consists of adding the readout signals from all detector probes. In that case, the error to the planned dwell positions is of 0.01 ± 0.14 mm and 0.02 ± 0.29 mm at spacings between the source and detector axes of 5.5 and 40 mm, respectively. Using this approach, the average deviations to the expected dwell time are of - 0.006 ± 0.009 $-0.006\,\pm \,0.009$ s and - 0.008 ± 0.058 $-0.008\, \pm 0.058$ s, at spacings between source and probe axes of 5.5 and 20 mm, respectively. CONCLUSIONS: Our six-probe Gd2 O2 S:Tb dosimeter coupled to a sCMOS camera can perform time-resolved treatment verification in HDR brachytherapy. This detection system of high spatial and temporal resolutions (0.25 mm and 0.06 s, respectively) provides a precise information on the treatment delivery via a dwell time and position verification of unmatched accuracy.


Subject(s)
Brachytherapy , Radiation Dosimeters , Radiotherapy Dosage , Brachytherapy/methods , Equipment Design , Algorithms
4.
Biomolecules ; 13(9)2023 09 20.
Article in English | MEDLINE | ID: mdl-37759819

ABSTRACT

Vascular calcification (VC) is a common complication in patients with chronic kidney disease which increases their mortality. Although oxidative stress is involved in the onset and progression of this disorder, the specific role of some of the main redox regulators, such as catalase, the main scavenger of H2O2, remains unclear. In the present study, epigastric arteries of kidney transplant recipients, a rat model of VC, and an in vitro model of VC exhibiting catalase (Cts) overexpression were analysed. Pericalcified areas of human epigastric arteries had increased levels of catalase and cytoplasmic, rather than nuclear runt-related transcription factor 2 (RUNX2). In the rat model, advanced aortic VC concurred with lower levels of the H2O2-scavenger glutathione peroxidase 3 compared to controls. In an early model of calcification using vascular smooth muscle cells (VSMCs), Cts VSMCs showed the expected increase in total levels of RUNX2. However, Cts VMSCs also exhibited a lower percentage of the nucleus stained for RUNX2 in response to calcifying media. In this early model of VC, we did not observe a dysregulation of the mitochondrial redox state; instead, an increase in the general redox state was observed in the cytoplasm. These results highlight the complex role of antioxidant enzymes as catalase by regulation of RUNX2 subcellular location delaying the onset of VC.


Subject(s)
Renal Insufficiency, Chronic , Vascular Calcification , Humans , Animals , Rats , Catalase , Core Binding Factor Alpha 1 Subunit/genetics , Hydrogen Peroxide , Oxidation-Reduction
5.
Open Res Eur ; 3: 78, 2023.
Article in English | MEDLINE | ID: mdl-37645487

ABSTRACT

The circular economy has a huge potential to make our societies more sustainable and decarbonised, with a reduced impact on the planet's resources. The deployment of innovative solutions in the field of urban biowaste valorisation and reuse is still hindered by numerous bottlenecks, such as technological readiness, funding and financing tools availability, quality and quantity of biowaste and regulatory barriers. The European Green Deal and associated legislative initiatives provide the opportunity to overcome the last ones. To promote innovative solutions for the European circular bioeconomy and help to overcome the barriers for the deployment of a circular bioeconomy, five Horizon 2020 projects working on biowaste valorisation have teamed up. This joint initiative is named ROOTS - circulaR pOlicies for changing the biOwasTe System. The projects HOOP, VALUEWASTE, SCALIBUR, WaysTUP! and CITYLOOPS are piloting new solutions to transform urban biowaste (food waste and green waste) and wastewater into valuable products like feed, fertilisers, bioplastics, biopesticides, proteins and bioethanol. They use different processes and technologies, but they all rely on high levels of recycling/upcycling and propose valorisation solutions relevant to the uptake of a truly circular bioeconomy. As a result of the work performed and experience acquired, a number of bottlenecks have been identified, on the following topics: biowaste prevention, recycling targets and treatment plants, waste and by-products, biopesticides, insects for animal feed, single cell protein, citizen behaviour, investment needs. For each identified bottleneck, this open letter proposes specifically 1) policy recommendations for each level of governance, and 2) information about solutions, good practices and concrete experiences from the participating projects.

6.
Phys Med Biol ; 67(24)2022 Dec 12.
Article in English | MEDLINE | ID: mdl-36240766

ABSTRACT

Purpose.HDR brachytherapy combines steep dose gradients in space and time, thereby requiring detectors of high spatial and temporal resolution to perform accurate treatment monitoring. We demonstrate a miniaturized fiber-integrated scintillator detector (MSD) of unmatched compactness which fulfills these conditions.Methods.The MSD consists of a 0.28 mm large and 0.43 mm long detection cell (Gd2O2S:Tb) coupled to a 110 micron outer diameter silica optical fiber. The fiber probe is tested in a phantom using a MicroSelectron 9.1 Ci Ir-192 HDR afterloader. The detection signal is acquired at a rate of 0.08 s with a standard sCMOS camera coupled to a chromatic filter (to cancel spurious Cerenkov signal). The dwell position and time monitoring are analyzed over prostate treatment sequences with dwell times spanning from 0.1 to 11 s. The dose rate at the probe position is both evaluated from a direct measurement and by reconstruction from the measured dwell position using the AAPM TG-43 formalism.Results.A total number of 1384 dwell positions are analyzed. In average, the measured dwell positions differ by 0.023 ± 0.077 mm from planned values over a 6-54 mm source-probe distance range. The standard deviation of the measured dwell positions is below 0.8 mm. 94% of the 966 dwell positions occurring at a source-probe inter-catheter spacing below 20 mm are successfully identified, with a 100% detection rate for dwell times exceeding 0.5 s. The average deviation to the planned dwell times is of 0.005 ± 0.060 s. The instant dose retrieval from dwell position monitoring leads to a relative mismatch to planned values of 0.14% ± 0.7%.Conclusion.A miniaturized Gd2O2S:Tb detector coupled to a standard sCMOS camera can be used for time-resolved treatment monitoring in HDR Brachytherapy.


Subject(s)
Brachytherapy , Male , Humans , Brachytherapy/methods , Phantoms, Imaging , Prostate , Catheters , Radiotherapy Dosage
7.
Melanoma Res ; 32(5): 343-352, 2022 10 01.
Article in English | MEDLINE | ID: mdl-35762583

ABSTRACT

Efficacy and safety of dabrafenib and trametinib in metastatic melanoma have been demonstrated in two-phase III and one-phase I/II clinical trials. However, patients at least 75 years old (y.o.) were largely underrepresented. Additionally, the safety profile of dabrafenib and trametinib based on age is unknown. ELDERLYMEL is a retrospective noninterventional multicenter study, describing the effectiveness and safety of at least 75 y.o. patients compared with less than 75 y.o. patients with advanced BRAF V600-mutated melanoma treated with dabrafenib plus trametinib or dabrafenib monotherapy. A total of 159 patients were included, 130 less than 75 y.o. and 29 at least 75 y.o. Clinical features were similar between the groups, except in the number of comorbidities, number of metastatic sites, Eastern Cooperative Oncology Group (ECOG) performance status, and BRAF V600-mutation type. Five patients per group received dabrafenib monotherapy. There were no differences in adverse events (AEs) rate or grade between the groups. However, AE profiles were different between the groups, being pyrexia infrequent in patients at least 75 y.o. (13.8% vs. 42.3%; P = 0.005). Dabrafenib and trametinib dose intensities were lower in at least 75 y.o. patients ( P = 0.018 and P = 0.020), but there were no differences in effectiveness between the groups. Finally, in a multivariate analysis, sex (female) was the only variable independently associated with an increased risk of AE grade ≥3. Data from the ELDERLYMEL study demonstrate that dabrafenib plus trametinib is safe and effective in at least 75 y.o. patients with advanced BRAF V600-mutated melanoma without increasing toxicity. Additionally, we describe a different safety profile depending on age and sex.


Subject(s)
Imidazoles , Melanoma , Oximes , Pyridones , Pyrimidinones , Skin Neoplasms , Aged , Antineoplastic Combined Chemotherapy Protocols , Data Analysis , Female , Humans , Imidazoles/therapeutic use , Male , Melanoma/drug therapy , Melanoma/genetics , Melanoma/pathology , Mutation , Oximes/therapeutic use , Proto-Oncogene Proteins B-raf/genetics , Pyridones/therapeutic use , Pyrimidinones/therapeutic use , Retrospective Studies , Skin Neoplasms/drug therapy , Skin Neoplasms/genetics , Skin Neoplasms/pathology
8.
Biomolecules ; 12(4)2022 03 28.
Article in English | MEDLINE | ID: mdl-35454102

ABSTRACT

Environmental factors, including pollutants and lifestyle, constitute a significant role in severe, chronic pathologies with an essential societal, economic burden. The measurement of all environmental exposures and assessing their correlation with effects on individual health is defined as the exposome, which interacts with our unique characteristics such as genetics, physiology, and epigenetics. Epigenetics investigates modifications in the expression of genes that do not depend on the underlying DNA sequence. Some studies have confirmed that environmental factors may promote disease in individuals or subsequent progeny through epigenetic alterations. Variations in the epigenetic machinery cause a spectrum of different disorders since these mechanisms are more sensitive to the environment than the genome, due to the inherent reversible nature of the epigenetic landscape. Several epigenetic mechanisms, including modifications in DNA (e.g., methylation), histones, and noncoding RNAs can change genome expression under the exogenous influence. Notably, the role of long noncoding RNAs in epigenetic processes has not been well explored in the context of exposome-induced tumorigenesis. In the present review, our scope is to provide relevant evidence indicating that epigenetic alterations mediate those detrimental effects caused by exposure to environmental toxicants, focusing mainly on a multi-step regulation by diverse noncoding RNAs subtypes.


Subject(s)
Epigenesis, Genetic , Exposome , Carcinogenesis/genetics , DNA Methylation , Humans , RNA, Untranslated/genetics
9.
Rev. cuba. cir ; 60(2): e1024, graf
Article in Spanish | LILACS, CUMED | ID: biblio-1280223

ABSTRACT

Introducción: El divertículo de Meckel es la anomalía congénita más frecuente del tracto gastrointestinal. Por lo general, cursa asintomático, y su diagnóstico es transoperatorio. Cuando presenta síntomas se deben a sus complicaciones, de las cuales la perforación constituye solo el 0,5 por ciento. Objetivo: Describir las características clínico-quirúrgicas de la presentación de un paciente con divertículo de Meckel perforado por cuerpo extraño. Caso clínico: Paciente adulto de 46 años de sexo masculino, piel blanca, que acude con dolor generalizado en el abdomen que se trasladó a Fosa Ilíaca Derecha, con febrícula. Se interviene quirúrgicamente y se halla divertículo de Meckel perforado por cuerpo extraño. Conclusiones: El pronóstico de esta enfermedad depende de la evolución, diagnóstico precoz y tratamiento aplicado en las distintas complicaciones, así como de la decisión de realizar tratamiento quirúrgico en los hallazgos casuales(AU)


Introduction: Meckel's diverticulum is the most frequent congenital anomaly of the gastrointestinal tract. It is generally asymptomatic, with an intraoperative diagnosis. When it presents symptoms, they are due to its complications, of which perforation accounts for only 0.5 percent. Objective: To describe the clinical-surgical characteristics of a patient who presented with a Meckel's diverticulum perforated by a foreign body. Clinical case: 46-year-old adult patient of the male sex and white skin, who presents with generalized pain in the abdomen that moved to the right iliac fossa and low-grade fever. The patient underwent surgery and a Meckel's diverticulum was found, perforated by a foreign body. Conclusions: The prognosis of this disease depends on the evolution, early diagnosis and applied treatment according to the different complications, as well as on the decision to perform surgical treatment in accidental findings(AU)


Subject(s)
Humans , Male , Middle Aged , Gastrointestinal Tract/abnormalities , Diverticulitis/surgery , Foreign Bodies/etiology , Meckel Diverticulum/complications , Early Diagnosis
10.
Nano Lett ; 21(8): 3410-3417, 2021 Apr 28.
Article in English | MEDLINE | ID: mdl-33830778

ABSTRACT

A wide variety of optical applications and techniques require control of light polarization. So far, the manipulation of light polarization relies on components capable of interchanging two polarization states of the transverse field of a propagating wave (e.g., linear to circular polarizations, and vice versa). Here, we demonstrate that an individual helical nanoantenna is capable of locally converting longitudinally oriented confined near-fields into a circularly polarized freely propagating wave, and vice versa. To this end, the nanoantenna is coupled to cylindrical surface plasmons bound to the top interface of a thin gold layer. Helices of constant and varying pitch lengths are experimentally investigated. The reciprocal conversion of an incoming circularly wave into diverging cylindrical surface plasmons is demonstrated as well. Interconnecting circularly polarized optical waves (carrying spin angular momentum) and longitudinal near-fields provides a new degree of freedom in light polarization control.

11.
Micromachines (Basel) ; 11(5)2020 Apr 30.
Article in English | MEDLINE | ID: mdl-32365889

ABSTRACT

We developed a portable device made of poly(dimethylsiloxane) (PDMS)/polymethylmethacrylate (PMMA) for long-term 3D cell culture of vascular endothelial cells for the development of a vascular network and evaluated the device under different transitions between normoxia and hypoxia with good optical accessibility. The combination of a nested reservoir device and a bicarbonate/ascorbate buffer system accomplished on-chip incubation with 4.91 ± 0.86% pO2 and 5.19 ± 1.70% pCO2 for up to 10 days. Seventy-two hours of normoxic incubation preceding hypoxic culture increased the cell viability, network formation, and size and stability of the resulting lumens compared with those completely maintained in normoxia for the same total duration. We employed different parameters of the network (e.g., total mesh area, total length, number of branches, among others) for the comparison of different oxygen treatments in the device. The differential effect of hypoxic conditions based on the maturity of the vessels may be used as an external factor to improve vascular development in vitro.

12.
Nutr. hosp ; 37(2): 238-242, mar.-abr. 2020. tab, graf
Article in English | IBECS | ID: ibc-190586

ABSTRACT

INTRODUCTION: a survey on peri-operative nutritional support in pancreatic and biliary surgery among Spanish hospitals in 2007 showed that few surgical groups followed the 2006 ESPEN guidelines. Ten years later we sent a questionnaire to check the current situation. METHODS: a questionnaire with 21 items sent to 38 centers, related to fasting time before and after surgery, nutritional screening use and type, time and type of peri-operative nutritional support, and number of procedures. RESULTS: thirty-four institutions responded. The median number of pancreatic resections (head/total) was 29.5 (95% CI: 23.0-35; range, 5-68) (total, 1002); of surgeries for biliary malignancies (non-pancreatic), 9.8 (95% CI: 7.3-12.4; range, 2-30); and of main biliary resections for benign conditions, 10.4 (95% CI: 7.6-13.3; range, 2-33). Before surgery, only 41.2% of the sites used nutritional support (< 50% used any nutritional screening procedure). The mean duration of preoperative fasting for solid foods was 9.3 h (range, 6-24 h); it was 6.6 h for liquids (range, 2-12). Following pancreatic surgery, 29.4% tried to use early oral feeding, but 88.2% of the surveyed teams used some nutritional support; 26.5% of respondents used TPN in 100% of cases. Different percentages of TPN and EN were used in the other centers. In malignant biliary surgery, 22.6% used TPN always, and EN in 19.3% of cases. CONCLUSIONS: TPN is the commonest nutrition approach after pancreatic head surgery. Only 29.4% of the units used early oral feeding, and 32.3% used EN; 22.6% used TPN regularly after surgery for malignant biliary tumours. The 2006 ESPEN guideline recommendations are not regularly followed 12 years after their publication in our country


INTRODUCCIÓN: realizamos una encuesta sobre soporte nutricional perioperatorio en cirugía pancreática y biliar en hospitales españoles en 2007, que mostró que pocos grupos quirúrgicos seguían las guías de ESPEN 2006. Diez años después enviamos un cuestionario para comprobar la situación actual. MÉTODOS: treinta y ocho centros recibieron un cuestionario con 21 preguntas sobre tiempo de ayunas antes y después de la cirugía, cribado nutricional, duración y tipo de soporte nutricional perioperatorio, y número de procedimientos. RESULTADOS: respondieron 34 grupos. La mediana de pancreatectomías (cabeza/total) fue de 29,5 (IC 95 %: 23,0-35; rango, 5-68) (total, 1002), la de cirugías biliares malignas de 9,8 (IC 95 %: 7,3-12,4; rango, 2-30) y la de resecciones biliares por patología benigna de 10,4 (IC 95 %: 7,6-13,3; rango, 2-33). Solo el 41,2 % de los grupos utilizaban soporte nutricional antes de la cirugía (< 50 % habian efectuado un cribado nutricional). El tiempo medio de ayuno preoperatorio para sólidos fue de 9,3 h (rango, 6-24 h), y de 6,6 h para líquidos (rango, 2-12). Tras la pancreatectomía, el 29,4 % habían intentado administrar una dieta oral precoz, pero el 88,2 % de los grupos usaron algún tipo de soporte nutricional y el 26,5 % usaron NP en el 100 % de los casos. Los demás grupos usaron diferentes porcentajes de NP y NE en sus casos. En la cirugía biliar maligna, el 22,6 % utilizaron NP siempre y NE en el 19,3 % de los casos. CONCLUSIONES: la NP es el soporte nutricional más utilizado tras la cirugía de cabeza pancreática. Solo el 29,4 % de las unidades usan nutrición oral precoz y el 32,3 % emplean la NE tras este tipo de cirugía. El 22,6 % de las instituciones usan NP habitualmente tras la cirugía de tumores biliares malignos. Las guías ESPEN 2006 no se siguen de forma habitual en nuestro país tras más de 10 años desde su publicación


Subject(s)
Humans , Nutritional Support/statistics & numerical data , Biliary Tract Surgical Procedures , Perioperative Period , Pancreatectomy , Nutritional Support/methods , Nutrition Surveys/methods , Spain
13.
Opt Express ; 27(24): 35588-35599, 2019 Nov 25.
Article in English | MEDLINE | ID: mdl-31878728

ABSTRACT

Fiber dosimeters have recently drawn much interest for measuring in vivo and in real time the dose of medical radiations. This paper presents the first miniaturized fiber dosimeter integrated at the end of a narrow 125 µm outer diameter optical fiber. Miniaturization is rendered possible by exploiting the concept of a leaky wave optical antenna for interfacing the scintillators and the fiber and by taking advantage of the low propagation loss of narrow silica fibers and high detection yield of single-pixel photon counters. Upon irradiation at 6 MV in air, our fiber probe leads to a linear detection response with a signal-to-noise ratio as high as 195. Although implemented with inorganic scintillators and fiber, our miniaturized fiber probe induces minimum screening effects on ionizing radiations over a negligible area (0.153 mm2). Our nano-optically driven approach may thus result in ultra-compact fiber dosimeters of negligible footprint in the radiotherapeutic processes, even with non-water equivalent fibers and scintillators. This opens new opportunities for a large panel of therapies relying on ionizing radiations (photons or charged particles).

14.
Opt Lett ; 44(19): 4861-4864, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31568461

ABSTRACT

Resonant plasmonic helices have been widely utilized for locally enhancing and tailoring optical chirality. Here we investigate their nonresonant operation through the recently introduced concept of a plasmonic helical "traveling-wave" nanoantenna. Relying on the coupling of a nonresonant plasmonic helix and a nano-aperture, the helical traveling-wave nanoantenna transmits circularly polarized light with the same handedness as the helix and blocks the other, with a measured dissymmetry factor larger than 1.92 (maximum value of 2). This chiroptical transmission is spatially localized, spectrally broadband, and background-free. Finally, we demonstrate the possibility to engineer such a plasmonic helical nanoantenna at the apex of a sharp tip typically used in scanning near-field microscopies, thus opening the route for moveable, broadband, and background-free chiroptical probes.

15.
Light Sci Appl ; 8: 76, 2019.
Article in English | MEDLINE | ID: mdl-31645922

ABSTRACT

Light polarization control is a key factor in modern photonics. Recent advances in surface plasmon manipulation have introduced the prospect of more compact and more efficient devices for this purpose. However, the current plasmonic-based polarization optics remain much larger than the wavelength of light, which limits the design degrees of freedom. Here, we present a plasmonic traveling-wave nanoantenna using a gold-coated helical carbon nanowire end-fired with a dipolar aperture nanoantenna. Our nonresonant helical nanoantenna enables tunable polarization control by swirling surface plasmons on the subwavelength scale and taking advantage of the optical spin-orbit interaction. Four closely packed helical traveling-wave nanoantennas (HTNs) are demonstrated to locally convert an incoming light beam into four beams of tunable polarizations and intensities, with the ability to impart different polarization states to the output beams in a controllable way. Moreover, by near-field coupling four HTNs of opposite handedness, we demonstrate a subwavelength waveplate-like structure providing a degree of freedom in polarization control that is unachievable with ordinary polarization optics and current metamaterials.

16.
Dermatology ; 235(4): 334-339, 2019.
Article in English | MEDLINE | ID: mdl-31112971

ABSTRACT

BACKGROUND: The recently implemented AJCC 8th edition TNM staging system for malignant melanoma (MM) changed the definition for T1a and T1b tumours. OBJECTIVES: To analyse differences in disease-free survival (DFS) among patients with thin MM staged according to both AJCC 7th and 8th editions. METHODS: An observational study including 285 patients with cutaneous thin MM (thickness ≤1 mm). Cases were staged as T1a and T1b using both 7th and 8th editions. Neither regional nor visceral diseases were present at diagnosis. DFS curves were generated according to the Kaplan-Meier method. RESULTS: An 8% shift of patients from a T1a towards a T1b stage group was observed after applying the AJCC 8th edition. According to this 8th edition, DFS for T1a patients was significantly longer than for T1b patients (log-rank test; p = 0.005); 5-year DFS for T1a and T1b was 100 and 95%, respectively (Wilcoxon test; p = 0.002). According to the AJCC 7th edition, DFS did not significantly differ for T1a and T1b patients; 5-year DFS for T1a and T1b was 99 and 97%, respectively (p > 0.05). CONCLUSIONS: The AJCC 8th edition seems to be a better tool for staging thin melanomas.


Subject(s)
Melanoma/mortality , Melanoma/pathology , Disease-Free Survival , Humans , Neoplasm Staging , Prognosis , United States
17.
Antibiotics (Basel) ; 7(3)2018 Jul 05.
Article in English | MEDLINE | ID: mdl-29976893

ABSTRACT

As part of the quality improvement program “Health Alliance for Prudent Prescribing, Yield And Use of anti-microbial Drugs In the Treatment of respiratory tract infections” (HAPPY AUDIT) South America, we planned to implement an intervention based on the use of quality indicators as a means to influence General Practitioners’ (GPs) prescribing decision. Knowledge on the acceptability and applicability of an intervention is crucial to decide whether the intervention is suitable and will achieve the expected outcomes. This study explores GPs’ views about the acceptability and applicability of using quality indicators as an intervention to influence their prescribing decision in patients with suspected Respiratory Tract Infections (RTIs) across four countries in South-America. In March 2015, GPs that were participating in HAPPY AUDIT South America were invited to participate in focus groups. A discussion guide covering the domains acceptability and applicability was used. Data was analyzed through systematic text condensation with an inductive approach. 171 GPs were invited and 48% participated. Acceptability ranged from totally acceptable to slightly acceptable. This spectrum of GPs views on acceptability was influenced by themes concerning applicability. In conclusion, there is a positive attitude towards the use of quality indicators. Nonetheless, applicability challenges have to be taken into consideration and solved if we are to achieve a large effect with the implementation of this intervention.

18.
J Orthop ; 15(2): 467-470, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29881178

ABSTRACT

Although the cement in cement technique is a simple method for exchanging cemented stems, it may be technical demanding. The different geometry of different-offset Exeter long stems can be a problem with this technique. We describe a case revision hip surgery as a consequence of neglected bipolar hemiarthroplasty dislocation in which a 44 mm offset long stem was exchanged by a shorter and smaller size 37.5 mm offset stem. The implications of the procedure and the surgical pitfalls are discussed.

19.
Arch Esp Urol ; 71(5): 486-494, 2018 Jun.
Article in Spanish | MEDLINE | ID: mdl-29889039

ABSTRACT

OBJECTIVES: To evaluate the association of positive margins in the intraoperative biopsy during radical cystectomy (RC) with the risk of recurrence in the uretero-ileal anastomosis or upper urinary tract (UUT), and identify potential risk factors for positive ureteral margins. METHODS: A retrospective, descriptive study was performed in patients treated with radical cystectomy due to transitional cell carcinoma (TCC), who underwent a cold biopsy of the ureteral margin at the time of cystectomy. A descriptive analysis and frequency distribution was performed. Fisher's test was used to calculate sensitivity and specificity and a survival analysis was performed. RESULTS: 230 patients were included. Prior to RC, transurethral resection of the bladder tumor and a CT scan were done. The percentage of positive margins was 4.81% for the right ureter and 4.27% for the left. Recurrence was detected in the anastomosis in 2.64% of the cases. In a 0.88% recurrence was found in the UUT (2 cases) at the level of left renal pelvis (1 case) and left kidney (1 case). In the multivariate analysis, neither recurrence in the anastomosis (p=1) or at the UUT (p=1) level during follow-up were significantly associated with the presence of positive margins. An association was found between the pathological biopsy of the right ureter and carcinoma in situ (CIS) of the bladder wall with UUT involvement. We found only association between the cold biopsy of the left ureter and tumor in left UTT. Reimplantation with positive margins was not statistically associated with neither ureteroileal anastomosis or UTT relapse. A relationship was found between the cold biopsy of both ureters and the definitive pathology. CONCLUSIONS: In our study, the presence of positive ureteral margins was not associated with an increased risk of recurrence in the anastomosis or UUT. Although it remains a topic for debate, a strategy to follow may be to adapt ureteral cold biopsies to individual risk, thus perform it in patients with bladder CIS.


Subject(s)
Cystectomy , Neoplasm Recurrence, Local , Ureter/pathology , Ureteral Neoplasms/pathology , Urinary Bladder Neoplasms/surgery , Aged , Biopsy/methods , Cold Temperature , Cystectomy/methods , Female , Humans , Intraoperative Period , Male , Margins of Excision , Neoplasm Recurrence, Local/epidemiology , Predictive Value of Tests , Retrospective Studies , Risk Assessment
20.
Arch. esp. urol. (Ed. impr.) ; 71(5): 486-494, jun. 2018. tab, graf
Article in Spanish | IBECS | ID: ibc-178429

ABSTRACT

OBJETIVOS: Evaluar la asociación de márgenes positivos en la biopsia intra-operatoria al tiempo de la cistectomía radical (CR) con el riesgo de recidiva en la anastomosis urétero-ileal o a nivel del tracto urinario superior (TUS), y estudiar posibles factores de riesgo preoperatorios asociados con el margen ureteral positivo. MÉTODO: Estudio descriptivo retrospectivo de pacientes tratados mediante CR debido a carcinoma de células transicionales (CCT), a los que se les realizó al tiempo de la CR una biopsia fría del margen ureteral. Se realizó un análisis descriptivo y distribuciones de frecuencias. Se empleó el test de Fisher, se calcularon los valores de sensibilidad (Se) y especificidad (Sp) de la prueba, y se realizó un análisis de supervivencia. RESULTADOS: Se incluyeron 230 pacientes que fueron sometidos a CR. Previamente a la CR se les realizó resección transuretral (RTU) de vejiga y tomografía axial computarizada (TC). El porcentaje de márgenes positivos fue de 4,8% para el uréter derecho y de 4,7% para el izquierdo. Se detectó recidiva en la anastomosis en el 2,6% de los casos. En un 0,8% se encontró recidiva en el TUS (2 casos) a nivel de pelvis renal izquierda (1 caso) y riñón izquierdo (1 caso). En el análisis multivariante, ni la recidiva en la anastomosis (p=1) ni a nivel del TUS (p=1) a lo largo del seguimiento, se asociaron de forma significativa con la presencia de márgenes positivos. De forma secundaria se estudiaron los posibles factores anatomopatológicos preoperatorios asociados con el riesgo de margen positivo, encontrando asociación entre la anatomía patológica (A-P) intraoperatoria del uréter derecho y CIS en la RTU vesical y con tumor del TUS asociado. La reimplantación con margen positivo no se asoció estadísticamente con recidiva en la anastomosis ni con recidiva en el TUS. Hubo relación entre A-P intraoperatoria de ambos uréteres y la definitiva. CONCLUSIONES: En nuestro estudio, la presencia de márgenes ureterales positivos no se asociaron con mayor riesgo de recidiva en la anastomosis o en el TUS. Aunque sigue siendo un tema a debate, una estrategia a seguir puede ser adaptar la biopsia fría ureteral al riesgo individual y realizarla a pacientes con CIS vesical


OBJECTIVES: To evaluate the association of positive margins in the intraoperative biopsy during radical cystectomy (RC) with the risk of recurrence in the uretero-ileal anastomosis or upper urinary tract (UUT), and identify potential risk factors for positive ureteral margins. METHODS: A retrospective, descriptive study was performed in patients treated with radical cystectomy due to transitional cell carcinoma (TCC), who underwent a cold biopsy of the ureteral margin at the time of cystectomy. A descriptive analysis and frequency distribution was performed. Fisher's test was used to calculate sensitivity and specificity and a survival analysis was performed. RESULTS: 230 patients were included. Prior to RC, transurethral resection of the bladder tumor and a CT scan were done. The percentage of positive margins was 4.81% for the right ureter and 4.27% for the left. Recurrence was detected in the anastomosis in 2.64% of the cases. In a 0.88% recurrence was found in the UUT (2 cases) at the level of left renal pelvis (1 case) and left kidney (1 case). In the multivariate analysis, neither recurrence in the anastomosis (p=1) or at the UUT (p=1) level during follow-up were significantly associated with the presence of positive margins. An association was found between the pathological biopsy of the right ureter and carcinoma in situ (CIS) of the bladder wall with UUT involvement. We found only association between the cold biopsy of the left ureter and tumor in left UTT. Reimplantation with positive margins was not statistically associated with neither ureteroileal anastomosis or UTT relapse. A relationship was found between the cold biopsy of both ureters and the definitive pathology. CONCLUSIONS: In our study, the presence of positive ureteral margins was not associated with an increased risk of recurrence in the anastomosis or UUT. Although it remains a topic for debate, a strategy to follow may be to adapt ureteral cold biopsies to individual risk, thus perform it in patients with bladder CIS


Subject(s)
Humans , Male , Female , Aged , Cystectomy/methods , Neoplasm Recurrence, Local/epidemiology , Ureter/pathology , Ureteral Neoplasms/pathology , Urinary Bladder Neoplasms/surgery , Biopsy/methods , Cold Temperature , Intraoperative Period , Margins of Excision , Predictive Value of Tests , Retrospective Studies , Risk Assessment
SELECTION OF CITATIONS
SEARCH DETAIL
...