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1.
Ann Oncol ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38866180

RESUMEN

BACKGROUND: Part 1 of the RUBY trial (NCT03981796) evaluated dostarlimab plus carboplatin-paclitaxel compared with placebo plus carboplatin-paclitaxel in patients with primary advanced or recurrent endometrial cancer. At the first interim analysis, the trial met one of its dual-primary endpoints with statistically significant progression-free survival benefits in the mismatch repair deficient/microsatellite instability-high (dMMR/MSI-H) and overall populations. Overall survival (OS) results are reported from the second interim analysis. PATIENTS AND METHODS: RUBY is a phase 3, global, double-blind, randomized, placebo-controlled trial. Part 1 of RUBY enrolled eligible patients with primary advanced stage III or IV or first recurrent endometrial cancer who were randomly assigned (1:1) to receive either dostarlimab (500 mg) or placebo, plus carboplatin-paclitaxel every 3 weeks for 6 cycles followed by dostarlimab (1000 mg) or placebo every 6 weeks for up to 3 years. OS was a dual-primary endpoint. RESULTS: A total of 494 patients were randomized (245 in dostarlimab arm; 249 in placebo arm). In the overall population, with 51% maturity, RUBY met the dual-primary endpoint for OS at this second interim analysis, with a statistically significant reduction in the risk of death (HR = 0.69; 95% CI, 0.54-0.89; P = 0.0020) in patients treated with dostarlimab plus carboplatin-paclitaxel versus carboplatin-paclitaxel alone. The risk of death was lower in the dMMR/MSI-H population (HR = 0.32; 95% CI, 0.17-0.63; nominal P = 0.0002) and a trend in favor of dostarlimab was seen in the mismatch repair proficient/microsatellite stable (MMRp/MSS) population (HR = 0.79; 95% CI, 0.60-1.04; nominal P = 0.0493). The safety profile for dostarlimab plus carboplatin-paclitaxel was consistent with the first interim analysis. CONCLUSIONS: Dostarlimab in combination with carboplatin-paclitaxel demonstrated a statistically significant and clinically meaningful overall survival benefit in the overall population of patients with primary advanced or recurrent endometrial cancer while demonstrating an acceptable safety profile.

2.
Anal Chem ; 94(50): 17467-17476, 2022 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-36480638

RESUMEN

Online spectroscopic measurements can be used to provide unique insight into complex chemical systems, enabling new understanding and optimization of chemical processes. A key example of this is discussed here with the monitoring of pH of various acid systems in real-time. In this work the acids used in multiple chemical separations processes, such as TALSPEAK (Trivalent Actinide-Lanthanide Separation by Phosphorus reagent Extraction from Aqueous Komplexes) and oxalate precipitation, were characterized. Raman spectroscopy, a robust optical approach that can be integrated in corrosive processes, was used to follow the unique fingerprints of the various protonated and deprotonated acid species. This data was analyzed using a hierarchical modeling approach to build a consolidated model scheme using optical fingerprints from all weak acids to measure pH associated with any of the weak acid systems studied here. Validation of system performance included utilizing Raman spectroscopy under dynamic flow conditions to monitor solution pH under changing process conditions in-line. Overall, the Raman based approach provided accurate analysis of weak acid solution pH.


Asunto(s)
Oxalatos , Espectrometría Raman , Espectrometría Raman/métodos , Quimiometría , Ácido Cítrico , Ácidos , Concentración de Iones de Hidrógeno
3.
J Perianesth Nurs ; 37(4): 551-556, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35400551

RESUMEN

PURPOSE: P Perioperative administration of single-dose dexamethasone helps reduce postoperative nausea and vomiting, inflammation, and pain. However, it is unclear which dose achieves these effects while minimizing the hyperglycemic impact in patients with diabetes. The purpose of this review was to elucidate the most appropriate perioperative dose of dexamethasone for diabetic patients, and whether it is necessary to withhold it in patients with poor glycemic control. DESIGN: A systematic review. METHODS: A literature search using PubMed and Cochrane Database of Systematic Reviews revealed 17 potential evidence sources. Eight sources met the inclusion criteria. Sources included one systematic review with meta-analysis, one randomized control trial, and six observational studies. FINDINGS: Evidence suggests diabetic patients who receive dexamethasone perioperatively are more likely to develop postoperative hyperglycemia, with a maximum blood glucose increase of 30 to 45 mg/dL in the first 24 hours following a single dose. One study described increased blood glucose levels with escalating doses, but no other sources have supported that finding. The available studies were markedly heterogeneous in both design and proportion of diabetic subjects included, and most were of low quality. CONCLUSIONS: There is not enough evidence to quantify the hyperglycemic effect of commonly used dexamethasone doses, and rigorous studies are needed to inform practice.


Asunto(s)
Dexametasona , Diabetes Mellitus , Glucemia , Dexametasona/uso terapéutico , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/cirugía , Humanos , Hiperglucemia/prevención & control , Náusea y Vómito Posoperatorios
4.
Anal Chem ; 93(14): 5890-5896, 2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33780245

RESUMEN

Complex chemical systems that exhibit varied and matrix-dependent speciation are notoriously difficult to monitor and characterize online and in real-time. Optical spectroscopy is an ideal tool for in situ characterization of chemical species that can enable quantification as well as species identification. Chemometric modeling, a multivariate method, has been successfully paired with optical spectroscopy to enable measurement of analyte concentrations even in complex solutions where univariate methods such as Beer's law analysis fail. Here, Raman spectroscopy is used to quantify the concentration of phosphoric acid and its three deprotonated forms during a titration. In this system, univariate approaches would be difficult to apply due to multiple species being present simultaneously within the solution as the pH is varied. Locally weighted regression (LWR) modeling was used to determine phosphate concentration from spectral signature. LWR results, in tandem with multivariate curve resolution modeling, provide a direct measurement of the concentration of each phosphate species using only the Raman signal. Furthermore, results are presented within the context of fundamental solution chemistry, including Pitzer equations, to compensate for activity coefficients and nonidealities associated with high ionic strength systems.

5.
Anal Chem ; 93(3): 1643-1651, 2021 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-33337856

RESUMEN

Microfluidics have many potential applications including characterization of chemical processes on a reduced scale, spanning the study of reaction kinetics using on-chip liquid-liquid extractions, sample pretreatment to simplify off-chip analysis, and for portable spectroscopic analyses. The use of in situ characterization of process streams from laboratory-scale and microscale experiments on the same chemical system can provide comprehensive understanding and in-depth analysis of any similarities or differences between process conditions at different scales. A well-characterized extraction of Nd(NO3)3 from an aqueous phase of varying NO3- (aq) concentration with tributyl phosphate (TBP) in dodecane was the focus of this microscale study and was compared to an earlier laboratory-scale study utilizing counter current extraction equipment. Here, we verify that this same extraction process can be followed on the microscale using spectroscopic methods adapted for microfluidic measurement. Concentration of Nd (based on UV-vis) and nitrate (based on Raman) was chemometrically measured during the flow experiment, and resulting data were used to determine the distribution ratio for Nd. Extraction distributions measured on the microscale were compared favorably with those determined on the laboratory scale in the earlier study. Both micro-Raman and micro-UV-vis spectroscopy can be used to determine fundamental parameters with significantly reduced sample size as compared to traditional laboratory-scale approaches. This leads naturally to time, cost, and waste reductions.

6.
Eur Heart J ; 41(3): 359-367, 2020 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-31513271

RESUMEN

AIMS: Symptom-based pretest probability scores that estimate the likelihood of obstructive coronary artery disease (CAD) in stable chest pain have moderate accuracy. We sought to develop a machine learning (ML) model, utilizing clinical factors and the coronary artery calcium score (CACS), to predict the presence of obstructive CAD on coronary computed tomography angiography (CCTA). METHODS AND RESULTS: The study screened 35 281 participants enrolled in the CONFIRM registry, who underwent ≥64 detector row CCTA evaluation because of either suspected or previously established CAD. A boosted ensemble algorithm (XGBoost) was used, with data split into a training set (80%) on which 10-fold cross-validation was done and a test set (20%). Performance was assessed of the (1) ML model (using 25 clinical and demographic features), (2) ML + CACS, (3) CAD consortium clinical score, (4) CAD consortium clinical score + CACS, and (5) updated Diamond-Forrester (UDF) score. The study population comprised of 13 054 patients, of whom 2380 (18.2%) had obstructive CAD (≥50% stenosis). Machine learning with CACS produced the best performance [area under the curve (AUC) of 0.881] compared with ML alone (AUC of 0.773), CAD consortium clinical score (AUC of 0.734), and with CACS (AUC of 0.866) and UDF (AUC of 0.682), P < 0.05 for all comparisons. CACS, age, and gender were the highest ranking features. CONCLUSION: A ML model incorporating clinical features in addition to CACS can accurately estimate the pretest likelihood of obstructive CAD on CCTA. In clinical practice, the utilization of such an approach could improve risk stratification and help guide downstream management.


Asunto(s)
Calcio/metabolismo , Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico , Vasos Coronarios/diagnóstico por imagen , Aprendizaje Automático , Sistema de Registros , Enfermedad de la Arteria Coronaria/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada Multidetector/métodos , Valor Predictivo de las Pruebas , Estudios Prospectivos , Curva ROC
7.
Anal Chem ; 92(8): 5882-5889, 2020 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-32223185

RESUMEN

Measurement of pH is an integral component of chemical studies and process control; however, traditional pH probes are difficult to utilize in harsh or complex chemical systems. Optical spectroscopy-based online monitoring offers a powerful and novel route for characterizing system parameters, such as pH, and is well adapted to deployment in harsh environments or chemically complex systems. Specifically, Raman spectroscopy combined with chemometric analysis can provide an improved method of online p[H+] measurement. Multivariate curve resolution (MCR) analysis of Raman spectra can be utilized to determine speciation as a function of p[H+], and the MCR scores assigned to each species can be used to calculate p[H+]. Subsequent chemometric modeling can be used to correlate spectral response to p[H+]. This was demonstrated with phosphoric acid, a chemical system known to challenge traditional pH probes. Raman spectra exhibit clear changes with pH due to changing speciation, and chemometric modeling can be successfully utilized to correlate those fingerprints to p[H+]. With the use of this approach, p[H+] of the phosphoric acid system can be accurately measured without foreknowledge of system conditions such as ionic strength.

8.
Cardiovasc Diabetol ; 19(1): 113, 2020 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-32682451

RESUMEN

BACKGROUND: The association between triglyceride glucose (TyG) index and coronary atherosclerotic change remains unclear. We aimed to evaluate the association between TyG index and coronary plaque progression (PP) using serial coronary computed tomography angiography (CCTA). METHODS: A total of 1143 subjects (aged 60.7 ± 9.3 years, 54.6% male) who underwent serial CCTA with available data on TyG index and diabetic status were analyzed from The Progression of AtheRosclerotic PlAque DetermIned by Computed TomoGraphic Angiography IMaging (PARADIGM) registry. PP was defined as plaque volume (PV) (mm3) at follow-up minus PV at index > 0. Annual change of PV (mm3/year) was defined as PV change divided by inter-scan period. Rapid PP was defined as the progression of percent atheroma volume (PV divided by vessel volume multiplied by 100) ≥ 1.0%/year. RESULTS: The median inter-scan period was 3.2 (range 2.6-4.4) years. All participants were stratified into three groups based on TyG index tertiles. The overall incidence of PP was 77.3%. Baseline total PV (group I [lowest]: 30.8 (0.0-117.7), group II: 47.2 (6.2-160.4), and group III [highest]: 57.5 (8.4-154.3); P < 0.001) and the annual change of total PV (group I: 5.7 (0.0-20.2), group II: 7.6 (0.5-23.5), and group III: 9.4 (1.4-27.7); P = 0.010) were different among all groups. The risk of PP (odds ratio [OR] 1.648; 95% confidence interval [CI] 1.167-2.327; P = 0.005) and rapid PP (OR 1.777; 95% CI 1.288-2.451; P < 0.001) was increased in group III compared to that in group I. TyG index had a positive and significant association with an increased risk of PP and rapid PP after adjusting for confounding factors. CONCLUSION: TyG index is an independent predictive marker for the progression of coronary atherosclerosis. Clinical registration ClinicalTrials.gov NCT02803411.


Asunto(s)
Glucemia/análisis , Angiografía por Tomografía Computarizada , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Tomografía Computarizada Multidetector , Placa Aterosclerótica , Triglicéridos/sangre , Anciano , Biomarcadores/sangre , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Sistema de Registros , Factores de Tiempo
9.
Neurobiol Dis ; 130: 104479, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31128207

RESUMEN

Children with the autosomal dominant single gene disorder, neurofibromatosis type 1 (NF1), display multiple structural and functional changes in the central nervous system, resulting in neuropsychological cognitive abnormalities. Here we assessed the pathological functional organization that may underlie the behavioral impairments in NF1 using resting-state functional connectivity MRI. Coherent spontaneous fluctuations in the fMRI signal across the entire brain were used to interrogate the pattern of functional organization of corticocortical and corticostriatal networks in both NF1 pediatric patients and mice with a heterozygous mutation in the Nf1 gene (Nf1+/-). Children with NF1 demonstrated abnormal organization of cortical association networks and altered posterior-anterior functional connectivity in the default network. Examining the contribution of the striatum revealed that corticostriatal functional connectivity was altered. NF1 children demonstrated reduced functional connectivity between striatum and the frontoparietal network and increased striatal functional connectivity with the limbic network. Awake passive mouse functional connectivity MRI in Nf1+/- mice similarly revealed reduced posterior-anterior connectivity along the cingulate cortex as well as disrupted corticostriatal connectivity. The striatum of Nf1+/- mice showed increased functional connectivity to somatomotor and frontal cortices and decreased functional connectivity to the auditory cortex. Collectively, these results demonstrate similar alterations across species, suggesting that NF1 pathogenesis is linked to striatal dysfunction and disrupted corticocortical connectivity in the default network.


Asunto(s)
Trastorno Autístico/etiología , Encéfalo/patología , Vías Nerviosas/patología , Neurofibromatosis 1/complicaciones , Neurofibromatosis 1/patología , Adolescente , Animales , Encéfalo/diagnóstico por imagen , Niño , Modelos Animales de Enfermedad , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Ratones , Vías Nerviosas/diagnóstico por imagen , Neurofibromatosis 1/diagnóstico por imagen
10.
Radiology ; 292(3): 597-605, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31335283

RESUMEN

Background Coronary artery fractional flow reserve (FFR) derived from CT angiography (FFTCT) enables functional assessment of coronary stenosis. Prior clinical trials showed 13%-33% of coronary CT angiography studies had insufficient quality for quantitative analysis with FFRCT. Purpose To determine the rejection rate of FFRCT analysis and to determine factors associated with technically unsuccessful calculation of FFRCT. Materials and Methods Prospectively acquired coronary CT angiography scans submitted as part of the Assessing Diagnostic Value of Noninvasive FFRCT in Coronary Care (ADVANCE) registry (https://ClinicalTrials.gov: NCT02499679) and coronary CT angiography series submitted for clinical analysis were included. The primary outcome was the FFRCT rejection rate (defined as an inability to perform quantitative analysis with FFRCT). Factors that were associated with FFRCT rejection rate were assessed with multiple linear regression. Results In the ADVANCE registry, FFRCT rejection rate due to inadequate image quality was 2.9% (80 of 2778 patients; 95% confidence interval [CI]: 2.1%, 3.2%). In the 10 621 consecutive patients who underwent clinical analysis, the FFRCT rejection rate was 8.4% (n = 892; 95% CI: 6.2%, 7.2%; P < .001 vs the ADVANCE cohort). The main reason for the inability to perform FFRCT analysis was the presence of motion artifacts (63 of 80 [78%] and 729 of 892 [64%] in the ADVANCE and clinical cohorts, respectively). At multivariable analysis, section thickness in the ADVANCE (odds ratio [OR], 1.04; 95% CI: 1.001, 1.09; P = .045) and clinical (OR, 1.03; 95% CI: 1.02, 1.04; P < .001) cohorts and heart rate in the ADVANCE (OR, 1.05; 95% CI: 1.02, 1.08; P < .001) and clinical (OR, 1.06; 95% CI: 1.05, 1.07; P < .001) cohorts were independent predictors of rejection. Conclusion The rates for technically unsuccessful CT-derived fractional flow reserve in the ADVANCE registry and in a large clinical cohort were 2.9% and 8.4%, respectively. Thinner CT section thickness and lower patient heart rate may increase rates of completion of CT fractional flow reserve analysis. Published under a CC BY 4.0 license. Online supplemental material is available for this article. See also the editorial by Sakuma in this issue.


Asunto(s)
Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/fisiopatología , Reserva del Flujo Fraccional Miocárdico/fisiología , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Estudios Prospectivos , Sistema de Registros , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
11.
Circ J ; 83(6): 1293-1301, 2019 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-30996150

RESUMEN

BACKGROUND: Coronary computed tomography angiography (cCTA)-derived fractional flow reserve (FFRCT) is a promising diagnostic method for the evaluation of coronary artery disease (CAD). However, clinical data regarding FFRCTin Japan are scarce, so we assessed the clinical impact of using FFRCTin a Japanese population.Methods and Results:The ADVANCE registry is an international prospective FFRCTregistry of patients suspected of CAD. Of 5,083 patients, 1,829 subjects enrolled from Japan were analyzed. Demographics, symptoms, cCTA, FFRCT, treatment strategy, and 90-day major cardiovascular events (MACE) were assessed. Reclassification of treatment strategy between cCTA alone and cCTA+FFRCToccurred in 55.8% of site investigations and in 56.9% in the core laboratory analysis. Patients with positive FFR (FFRCT≤0.80) were less likely to have non-obstructive disease on invasive coronary angiography than patients with negative FFR (FFRCT>0.80) (20.5% vs. 46.1%, P=0.0001). After FFRCT, 67.0% of patients with positive results underwent revascularization, whereas 96.1% of patients with negative FFRCTwere medically treated. MACE occurred in 5 patients with positive FFRCT, but none occurred in patients with negative FFRCTwithin 90 days. CONCLUSIONS: In this Japanese population, FFRCTmodified the treatment strategy in more than half of the patients. FFRCTshowed potential for stratifying patients suspected of CAD properly into invasive or non-invasive management pathways.


Asunto(s)
Angiografía por Tomografía Computarizada , Enfermedad de la Arteria Coronaria , Reserva del Flujo Fraccional Miocárdico , Anciano , Anciano de 80 o más Años , Pueblo Asiatico , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/fisiopatología , Enfermedad de la Arteria Coronaria/cirugía , Humanos , Japón , Persona de Mediana Edad , Estudios Prospectivos , Sistema de Registros
12.
Anal Chem ; 90(4): 2548-2554, 2018 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-29381059

RESUMEN

Microfluidic devices are a growing field with significant potential for applications to small scale processing of solutions. Much like large scale processing, fast, reliable, and cost-effective means of monitoring streams during processing are needed. Here we apply a novel micro-Raman probe to the online monitoring of streams within a microfluidic device. For either macro- or microscale process monitoring via spectroscopic response, interfering or confounded bands can obfuscate results. By utilizing chemometric analysis, a form of multivariate analysis, species can be accurately quantified in solution despite the presence of overlapping or confounding spectroscopic bands. This is demonstrated on solutions of HNO3 and NaNO3 within microflow and microfluidic devices.

13.
Anal Chem ; 90(14): 8345-8353, 2018 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-29733195

RESUMEN

Microfluidic devices provide ideal environments to study solvent extraction. When droplets form and generate plug flow down the microfluidic channel, the device acts as a microreactor in which the kinetics of chemical reactions and interfacial transfer can be examined. Here, we present a methodology that combines chemometric analysis with online micro-Raman spectroscopy to monitor biphasic extractions within a microfluidic device. Among the many benefits of microreactors is the ability to maintain small sample volumes, which is especially important when studying solvent extraction in harsh environments, such as in separations related to the nuclear fuel cycle. In solvent extraction, the efficiency of the process depends on complex formation and rates of transfer in biphasic systems. Thus, it is important to understand the kinetic parameters in an extraction system to maintain a high efficiency and effectivity of the process. This monitoring provided concentration measurements in both organic and aqueous plugs as they were pumped through the microfluidic channel. The biphasic system studied was comprised of HNO3 as the aqueous phase and 30% (v/v) tributyl phosphate in n-dodecane comprised the organic phase, which simulated the plutonium uranium reduction extraction (PUREX) process. Using pre-equilibrated solutions (post extraction), the validity of the technique and methodology is illustrated. Following this validation, solutions that were not equilibrated were examined and the kinetics of interfacial mass transfer within the biphasic system were established. Kinetic results of extraction were compared to kinetics already determined on a macro scale to prove the efficacy of the technique.

14.
Nat Methods ; 12(6): 568-76, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25915120

RESUMEN

We describe an engineered family of highly antigenic molecules based on GFP-like fluorescent proteins. These molecules contain numerous copies of peptide epitopes and simultaneously bind IgG antibodies at each location. These 'spaghetti monster' fluorescent proteins (smFPs) distributed well in neurons, notably into small dendrites, spines and axons. smFP immunolabeling localized weakly expressed proteins not well resolved with traditional epitope tags. By varying epitope and scaffold, we generated a diverse family of mutually orthogonal antigens. In cultured neurons and mouse and fly brains, smFP probes allowed robust, orthogonal multicolor visualization of proteins, cell populations and neuropil. smFP variants complement existing tracers and greatly increase the number of simultaneous imaging channels, and they performed well in advanced preparations such as array tomography, super-resolution fluorescence imaging and electron microscopy. In living cells, the probes improved single-molecule image tracking and increased yield for RNA-seq. These probes facilitate new experiments in connectomics, transcriptomics and protein localization.


Asunto(s)
Proteínas Luminiscentes/química , Microscopía Electrónica/métodos , Microscopía Fluorescente/métodos , Animales , Antígenos , Mapeo Encefálico , Drosophila , Ratones , Modelos Moleculares , Datos de Secuencia Molecular , Neuronas , Conformación Proteica
15.
Catheter Cardiovasc Interv ; 92(2): 222-246, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-30160001

RESUMEN

The stimulus to create this document was the recognition that ionizing radiation-guided cardiovascular procedures are being performed with increasing frequency, leading to greater patient radiation exposure and, potentially, to greater exposure to clinical personnel. While the clinical benefit of these procedures is substantial, there is concern about the implications of medical radiation exposure. ACC leadership concluded that it is important to provide practitioners with an educational resource that assembles and interprets the current radiation knowledge base relevant to cardiovascular procedures. By applying this knowledge base, cardiovascular practitioners will be able to select procedures optimally, and minimize radiation exposure to patients and to clinical personnel. "Optimal Use of Ionizing Radiation in Cardiovascular Imaging - Best Practices for Safety and Effectiveness" is a comprehensive overview of ionizing radiation use in cardiovascular procedures and is published online. To provide the most value to our members, we divided the print version of this document into 2 focused parts. "Part I: Radiation Physics and Radiation Biology" addresses radiation physics, dosimetry and detrimental biologic effects. "Part II: Radiologic Equipment Operation, Dose-Sparing Methodologies, Patient and Medical Personnel Protection" covers the basics of operation and radiation delivery for the 3 cardiovascular imaging modalities (x-ray fluoroscopy, x-ray computed tomography, and nuclear scintigraphy). For each modality, it includes the determinants of radiation exposure and techniques to minimize exposure to both patients and to medical personnel.


Asunto(s)
Técnicas de Imagen Cardíaca/normas , Enfermedades Cardiovasculares/diagnóstico por imagen , Exposición Profesional/normas , Dosis de Radiación , Exposición a la Radiación/normas , Benchmarking/normas , Consenso , Medicina Basada en la Evidencia/normas , Humanos , Exposición Profesional/efectos adversos , Exposición Profesional/prevención & control , Seguridad del Paciente/normas , Valor Predictivo de las Pruebas , Exposición a la Radiación/efectos adversos , Exposición a la Radiación/prevención & control , Medición de Riesgo , Factores de Riesgo
16.
Catheter Cardiovasc Interv ; 92(2): 203-221, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-30160013

RESUMEN

The stimulus to create this document was the recognition that ionizing radiation-guided cardiovascular procedures are being performed with increasing frequency, leading to greater patient radiation exposure and, potentially, to greater exposure for clinical personnel. Although the clinical benefit of these procedures is substantial, there is concern about the implications of medical radiation exposure. The American College of Cardiology leadership concluded that it is important to provide practitioners with an educational resource that assembles and interprets the current radiation knowledge base relevant to cardiovascular procedures. By applying this knowledge base, cardiovascular practitioners will be able to select procedures optimally, and minimize radiation exposure to patients and to clinical personnel. Optimal Use of Ionizing Radiation in Cardiovascular Imaging: Best Practices for Safety and Effectiveness is a comprehensive overview of ionizing radiation use in cardiovascular procedures and is published online. To provide the most value to our members, we divided the print version of this document into 2 focused parts. Part I: Radiation Physics and Radiation Biology addresses the issue of medical radiation exposure, the basics of radiation physics and dosimetry, and the basics of radiation biology and radiation-induced adverse effects. Part II: Radiological Equipment Operation, Dose-Sparing Methodologies, Patient and Medical Personnel Protection covers the basics of operation and radiation delivery for the 3 cardiovascular imaging modalities (x-ray fluoroscopy, x-ray computed tomography, and nuclear scintigraphy) and will be published in the next issue of the Journal.


Asunto(s)
Técnicas de Imagen Cardíaca/normas , Enfermedades Cardiovasculares/diagnóstico por imagen , Dosis de Radiación , Exposición a la Radiación/normas , Benchmarking/normas , Consenso , Medicina Basada en la Evidencia/normas , Humanos , Seguridad del Paciente/normas , Valor Predictivo de las Pruebas , Exposición a la Radiación/efectos adversos , Exposición a la Radiación/prevención & control , Medición de Riesgo , Factores de Riesgo
17.
Analyst ; 143(5): 1188-1196, 2018 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-29417962

RESUMEN

To simplify and improve the safety of reprocessing used nuclear fuel, an initial assessment was made of Raman microscopy applied to microfluidic volumes with a view toward the on-line spectroscopic measurement of highly radioactive solutions. This study compares a microscopic Raman probe (excitation focal point diameter 70 µm) to a larger, well studied probe (excitation focal point diameter 125 µm) used in prior investigations. This was done by chemometrically modeling and predicting concentrations of HNO3 solutions (0 M to 8 M) as they flowed through microfluidic cells based upon spectra from each probe. Spectra recorded for each probe using the same static HNO3 solution set contained in 2 dram glass vials were used as training sets to produce models for the respective probes. Modeling required baseline, normalization and smoothing preprocessing to compensate for a reduced path length between the static glass vial training set (4 cm) and the reduced path length flow cell (1 cm), wide ranging solution concentrations, and the associated non-linear spectral changes, and abrupt and uneven concentration changes of flowing solutions. The micro-Raman probe is able to produce spectra that may be analyzed chemometrically to accurately predict the concentration of flowing HNO3 solutions down to microliter volumes. Based upon RMSECV and RMSEP modeling statistics concentration predictions of the micro-Raman probe are comparable to those obtained for a macro-Raman on identical samples.

19.
Scand J Rheumatol ; 46(4): 296-302, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27600931

RESUMEN

OBJECTIVES: To investigate whether antibody response patterns against Klebsiella pneumoniae capsular serotypes can discriminate patients with axial spondyloarthritis (axSpA) from patients with non-specific low back pain (LBP). METHOD: Immunoglobulin (Ig)G and IgA antibodies against K. pneumoniae capsular serotypes K2, K26, K36, and K50 were measured, and antibody seropositivity compared between groups and analysed for patient correlation in five different groups: (a) 96 patients fulfilling the Assessment of SpondyloArthritis International Society (ASAS) classification criteria for axSpA; (b) 38 patients with either a positive magnetic resonance imaging (MRI) scan as defined by ASAS or a positive human leucocyte antigen (HLA)-B27 status plus one clinical SpA feature, characterized as 'non-axSpA'; (c) 82 non-specific LBP patients; (d) 40 healthy blood donors and (e) 43 patients with diagnosed ankylosing spondylitis (AS) served as the negative and positive control groups. RESULTS: There was no difference in IgG and IgA seropositivity against all serotypes between the axSpA, non-axSpA, and LBP groups. No significant correlations were found between anti-Klebsiella antibodies and age, gender, HLA-B27, or high-sensitivity C-reactive protein (hsCRP). IgG seropositivity against K50 was more frequent in AS (25.6%) than in axSpA (13.5%, p < 0.05). axSpA patients with radiographic sacroiliitis and AS controls concordantly had the highest frequency of seropositivity for ≥ 2 serotypes (21%). CONCLUSIONS: The antibody patterns against K. pneumoniae serotypes K2, K26, K36, and K50 did not discriminate between early axSpA and non-specific LBP.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Klebsiella pneumoniae/inmunología , Dolor de la Región Lumbar/inmunología , Sacroileítis/inmunología , Espondiloartropatías/inmunología , Adolescente , Adulto , Cápsulas Bacterianas/inmunología , Proteína C-Reactiva/inmunología , Estudios de Casos y Controles , Dinamarca , Femenino , Antígeno HLA-B27/genética , Humanos , Inmunoglobulina A/inmunología , Inmunoglobulina G/inmunología , Imagen por Resonancia Magnética , Masculino , Sacroileítis/diagnóstico por imagen , Sacroileítis/genética , Serogrupo , Espondiloartropatías/diagnóstico por imagen , Espondiloartropatías/genética , Espondilitis Anquilosante/diagnóstico por imagen , Espondilitis Anquilosante/genética , Espondilitis Anquilosante/inmunología , Adulto Joven
20.
Arterioscler Thromb Vasc Biol ; 35(4): 981-9, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25676000

RESUMEN

OBJECTIVE: We sought to examine the risk of mortality associated with nonobstructive coronary artery disease (CAD) and to determine the impact of baseline statin and aspirin use on mortality. APPROACH AND RESULTS: Coronary computed tomographic angiography permits direct visualization of nonobstructive CAD. To date, the prognostic implications of nonobstructive CAD and the potential benefit of directing therapy based on nonobstructive CAD have not been carefully examined. A total of 27 125 consecutive patients who underwent computed tomographic angiography (12 enrolling centers and 6 countries) were prospectively entered into the COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter (CONFIRM) registry. Patients, without history of previous CAD or obstructive CAD, for whom baseline statin and aspirin use was available were analyzed. Each coronary segment was classified as normal or nonobstructive CAD (1%-49% stenosis). Patients were followed up for a median of 27.2 months for all-cause mortality. The study comprised 10 418 patients (5712 normal and 4706 with nonobstructive CAD). In multivariable analyses, patients with nonobstructive CAD had a 6% (95% confidence interval, 1%-12%) higher risk of mortality for each additional segment with nonobstructive plaque (P=0.021). Baseline statin use was associated with a reduced risk of mortality (hazard ratio, 0.44; 95% confidence interval, 0.28-0.68; P=0.0003), a benefit that was present for individuals with nonobstructive CAD (hazard ratio, 0.32; 95% confidence interval, 0.19-0.55; P<0.001) but not for those without plaque (hazard ratio, 0.66; 95% confidence interval, 0.30-1.43; P=0.287). When stratified by National Cholesterol Education Program/Adult Treatment Program III, no mortality benefit was observed in individuals without plaque. Aspirin use was not associated with mortality benefit, irrespective of the status of plaque. CONCLUSIONS: The presence and extent of nonobstructive CAD predicted mortality. Baseline statin therapy was associated with a significant reduction in mortality for individuals with nonobstructive CAD but not for individuals without CAD. CLINICAL TRIAL REGISTRATION: URL: http://clinicaltrials.gov/. Unique identifier NCT01443637.


Asunto(s)
Aspirina/uso terapéutico , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Estenosis Coronaria/tratamiento farmacológico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Prevención Primaria/métodos , Tomografía Computarizada por Rayos X , Adulto , Anciano , Asia , Canadá , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/mortalidad , Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/mortalidad , Europa (Continente) , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores Protectores , Sistema de Registros , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
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