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1.
Phys Rev Lett ; 132(24): 240803, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38949355

RESUMEN

We investigate the classical and quantum metrology of performing parameter estimation with interacting trapped bosons, which we theoretically treat by a self-consistent many-body approach of the multiconfigurational Hartree type. Focusing on a tilted double-well geometry, we compare a self-consistently determined and monitored two-mode truncation, with dynamically changing orbitals, to the conventional two-mode approach of fixed orbitals, where only Fock space coefficients evolve in time. We demonstrate that, as a consequence, various metrological quantities associated to a concrete measurement such as the classical Fisher information and the maximum likelihood estimator are deeply affected by the orbitals' change during the quantum evolution. Self-consistency of the quantum many-body dynamics of interacting trapped ultracold gases thus fundamentally affects the attainable parameter estimation accuracy of a given metrological protocol.

2.
Ann Vasc Surg ; 101: 72-79, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38110083

RESUMEN

BACKGROUND: Protamine administration was shown to reduce bleeding after carotid surgery but the role of protamine during peripheral vascular interventions (PVIs) remains unknown. This study evaluates the trend and outcomes of protamine use in the Vascular Quality Initiative (VQI). Our hypothesis is that the use of protamine is associated with decreased bleeding after PVI. METHODS: Patients undergoing elective PVI in the VQI (2016-2020) for peripheral arterial disease were reviewed and the utilization trend for protamine was described. The characteristics of patients undergoing PVI with and without protamine use were compared. After propensity score matching based on the patient's comorbidities, access site, and procedural characteristics, the perioperative outcomes of both groups were compared using multivariable Poisson regression to estimate adjusted rate ratios (aRRs) and 95% confidence intervals (95% CIs). RESULTS: The total number of patients was 131,618 and patients who received protamine constituted 29.8% of the sample (N = 38,191). After propensity matching, the total number of patients was 94,582, and patients who received protamine constituted 28.8% of the sample (N = 27,275). Protamine use significantly increased during the study period from 5.2 to 22.9%. Before propensity score matching, patients who received protamine were more likely to be white (79% vs. 76.8, P ≤ 0.001), smokers (80.5% vs. 78.5%, P ≤ 0.001), with medical comorbidities including hypertension (88.9% vs. 88.5%, P = 0.074), congestive heart failure (20.5% vs. 19.8%, P = 0.006), and chronic obstructive pulmonary disease (28.2% vs. 26.5%). They were also more likely to be on perioperative medications such as P2Y12 inhibitors (44.3% vs. 45, P = 0.013%) and statin (77.4% vs. 76.5%, P = 0.001) compared to patients who did not receive protamine. After propensity matching, there were no significant differences between the 2 groups. There was a significant decrease in bleeding during procedures where protamine was administered compared to no protamine (2.0% vs. 2.2%) (aRR, 0.89 [95% CI 0.80, 0.98]). Protamine was more likely to be given in procedures complicated by perforation (0.8% vs. 0.5%) (aRR, 1.48 [95% CI 1.24, 1.76]) and less likely to be given during procedures with distal embolization (0.4% vs. 0.7%) (aRR, 0.59 [95% CI 0.49, 0.73]). However, patients receiving protamine had significantly higher cardiac complications (1.4% vs. 1.1%) (aRR, 1.27 [95% CI 1.12, 1.43]). There was no significant difference in mortality between the 2 groups. CONCLUSIONS: Protamine use is associated with decreased perioperative bleeding but increased cardiac complications. Protamine should be selectively administered to patients at high risk of bleeding during PVI.


Asunto(s)
Hemorragia , Enfermedad Arterial Periférica , Humanos , Factores de Riesgo , Sistema de Registros , Resultado del Tratamiento , Comorbilidad , Enfermedad Arterial Periférica/diagnóstico , Enfermedad Arterial Periférica/terapia , Estudios Retrospectivos
3.
J Endovasc Ther ; : 15266028231187200, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37449379

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the technical feasibility, safety, and early outcomes of a snare-less, endovascular abdominal aortic aneurysm repair (EVAR)-first technique (SET) for iliac branch endoprosthesis (IBE) placement. METHODS: We retrospectively reviewed all patients who received IBEs between July 2018 and March 2022. Patients were divided into 2 categories based on method of IBE deployment: SET or Standard. Primary endpoints were technical success, major adverse events, mortality, reintervention, internal iliac artery (IIA) patency, and freedom from IIA branch instability. Technical success was defined by successful deployment of both the EVAR and the IBE with maintained patency of the IIA and no stent graft migration. RESULTS: There were 20 patients (90% male, median age 72 [65.4-74.5] years) who underwent IBE placement. Among these, 5 (33.3%) underwent SET to treat 5 common iliac artery (CIA)/IIA aneurysms, while the remaining 15 (66.7%) underwent standard IBE deployment with through-and-through femoral access (n=13) or trans-brachial access (n=2) to treat 19 CIA/IIA aneurysms. Overall median renal to iliac bifurcation length was 169 (152-177) mm, with 9 patients falling short of the minimum of 165 mm for on-label IBE placement. Median contrast used was 148 (120-201) mL, fluoroscopy time 42.8 (35.0-49.8) minutes, estimated blood loss 200 (100-275) mL, and procedure time 192 (167-246) minutes, with no significant differences between the 2 groups. Technical success was achieved in 100% of cases. At 30 days, there were no mortalities or major adverse events in either group; there were 100% IIA patency, no IIA instability, and no reinterventions in both groups. Median follow-up in the SET group was 5.7 (5.5-6.2) months, with 1 death at 6 months and 1 type 1B endoleak at 6 months requiring reintervention. Median follow-up for the Standard group was 1.6 (0.8-2.1) years with 2 non-aneurysm-related deaths and no reinterventions at 1 year. CONCLUSIONS: SET for IBE is a safe and effective approach that decreases technical complexity and mitigates anatomic barriers to IBE placement. CLINICAL IMPACT: SET for IBE is a safe and effective approach to IBE placement that decreases technical complexity. A critical component to this technique is a large bore sheath with a stiff steerable tip. Importantly, this approach also mitigates anatomic barriers to IBE placement, expanding applicability of IBE technology to patients who may be otherwise ineligible.

4.
Med Teach ; 45(1): 111-113, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35912520

RESUMEN

The composition of early trainee medical education is highly influential as it shapes the future of medicine and healthcare. Despite being frequently neglected, education about and exposure to hospital administration should be important aspects of medical student learning. Understanding how health systems coordinate and optimize functions of different departments to enhance patient care is a critical component of being a physician. In this Personal View, we share the tangible impact that a short immersive experience with hospital administration can bring to not only enrich medical student education but also influence their future perspectives and interactions within healthcare systems. Early integration of these learning opportunities has the potential to improve the physician-administrator relationship within hospitals and encourage innovative collaboration to provide more patient-centered and financially sustainable healthcare.


Asunto(s)
Educación Médica , Médicos , Estudiantes de Medicina , Humanos , Aprendizaje , Atención a la Salud , Escolaridad
5.
Plant Cell Environ ; 45(4): 1315-1332, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35064681

RESUMEN

The dynamic behaviour of seeds in soil seed banks depends on their ability to act as sophisticated environmental sensors to adjust their sensitivity thresholds for germination by dormancy mechanisms. Here we show that prolonged incubation of sugar beet fruits at low temperature (chilling at 5°C, generally known to release seed dormancy of many species) can induce secondary nondeep physiological dormancy of an apparently nondormant crop species. The physiological and biophysical mechanisms underpinning this cold-induced secondary dormancy include the chilling-induced accumulation of abscisic acid in the seeds, a reduction in the embryo growth potential and a block in weakening of the endosperm covering the embryonic root. Transcriptome analysis revealed distinct gene expression patterns in the different temperature regimes and upon secondary dormancy induction and maintenance. The chilling caused reduced expression of cell wall remodelling protein genes required for embryo cell elongation growth and endosperm weakening, as well as increased expression of seed maturation genes, such as for late embryogenesis abundant proteins. A model integrating the hormonal signalling and master regulator expression with the temperature-control of seed dormancy and maturation programmes is proposed. The revealed mechanisms of the cold-induced secondary dormancy are important for climate-smart agriculture and food security.


Asunto(s)
Beta vulgaris , Ácido Abscísico/metabolismo , Beta vulgaris/genética , Germinación/fisiología , Latencia en las Plantas/genética , Semillas/fisiología
6.
Ann Vasc Surg ; 86: 328-337, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35589028

RESUMEN

BACKGROUND: The purpose of this study is to elucidate the role of the AFX2 platform in the endovascular treatment of aortic pathology. METHODS: All procedures by a single surgeon resulting in implantation of a bifurcated unibody stent graft were reviewed retrospectively. Indications for selection of the AFX2 endograft in each case were evaluated. Aortic anatomy was determined via review of pre-operative computed tomography (CT) scans. Cumulative event probabilities for endoleak, reintervention, and mortality were estimated. Patient and procedural details were described using mean, standard deviation, medians, and interquartile range (IQR). Kaplan-Meier survival analysis estimated freedom from mortality and reintervention. Cumulative incidence probabilities were calculated as one minus the Kaplan-Meier estimator. RESULTS: Between March 2018 and December 2020, the author (NN) used 142 aortic endografts in 142 patients. Of these, 46 (32.4%) were AFX2 endografts and the remaining were modular bifurcated devices, predominantly Medtronic Endurant II and Terumo Treo. No AFX-Strata or AFX-Duraply devices were placed. Amongst the patients who received an AFX2, mean age was 71.3 +/- 9.8 years with 84.8% male. Median operative time was 116 (86-166) min, with contrast dose of 79 (41-120) milliliters and fluoroscopy time of 12 (8.6-18) min. Overall, 78.3% (n = 36) of AFX2 devices were placed in aortas with maximum true lumen diameter <5.0 cm. Median postoperative follow-up was 1.7 years (IQR 1.0-2.4 years), with a maximum follow-up of 3.6 years. There was 1 patient lost to follow-up at 5 months. The 2-year incidence of type II endoleak, reintervention, and all-cause mortality was 12.7% (95% confidence interval CI, 0-29.6%), 2.2% (95% CI, 0-6.3%), and 11.3% (95% CI, 0.1-2.1.2%), respectively. There were no type I or III endoleaks. CONCLUSIONS: The AFX2 endograft plays a safe and effective role in treatment of infrarenal aortic pathologies that may be otherwise more technically challenging for traditional modular, bifurcated devices.


Asunto(s)
Aneurisma de la Aorta Abdominal , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Humanos , Masculino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Femenino , Endofuga/diagnóstico por imagen , Endofuga/etiología , Endofuga/cirugía , Prótesis Vascular/efectos adversos , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Aneurisma de la Aorta Abdominal/complicaciones , Estudios Retrospectivos , Diseño de Prótesis , Resultado del Tratamiento , Stents/efectos adversos , Aorta/cirugía
7.
J Vasc Surg ; 73(2): 392-398, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32622075

RESUMEN

Implementation of telemedicine for patient encounters optimizes personal safety and allows for continuity of patient care. Embracing telehealth reduces the use of personal protective equipment and other resources consumed during in-person visits. The use of telehealth has increased to historic levels in response to the coronavirus disease 2019 (COVID-19) pandemic. Telehealth may be a key modality to fight against COVID-19, allowing us to take care of patients, conserve personal protective equipment, and protect health care workers all while minimizing the risk of viral spread. We must not neglect vascular health issues while the coronavirus pandemic continues to flood many hospitals and keep people confined to their homes. Patients are not immune to diseases and illnesses such as stroke, critical limb ischemia, and deep vein thrombosis while being confined to their homes and afraid to visit hospitals. Emerging from the COVID-19 crisis, incorporating telemedicine into routine medical care is transformative. By leveraging digital technology, the authors discuss their experience with the implementation, workflow, coding, and reimbursement issues of telehealth during the COVID-19 era.


Asunto(s)
COVID-19 , Pandemias , Atención al Paciente , Telemedicina , Enfermedades Vasculares , Codificación Clínica , Humanos , Reembolso de Seguro de Salud/economía , Reembolso de Seguro de Salud/normas , Licencia Médica , Aplicaciones Móviles , Atención al Paciente/economía , Atención al Paciente/métodos , Atención al Paciente/normas , Selección de Paciente , SARS-CoV-2 , Telemedicina/economía , Telemedicina/organización & administración , Telemedicina/normas , Telemedicina/tendencias , Estados Unidos , United States Department of Veterans Affairs , Enfermedades Vasculares/diagnóstico , Enfermedades Vasculares/economía , Enfermedades Vasculares/terapia , Flujo de Trabajo
8.
Ann Vasc Surg ; 72: 517-528, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32927042

RESUMEN

BACKGROUND: Patients with chronic limb-threatening ischemia (CLTI) at the extremes of age are thought to have distinct risk factor profiles and poor outcomes after lower extremity revascularization (LER). The aim of this study is to examine the relationships among age, risk factor profiles, and outcomes of LER in patients with CLTI in a large database focusing on the extreme age groups. METHODS: Patients undergoing LER for CLTI in the Vascular Quality Initiative suprainguinal bypass, infrainguinal bypass, and peripheral vascular intervention files were reviewed through 2019. Patients were stratified into 3 groups: premature peripheral artery disease (PAD) (≤50 years old), 51-84 years old, and elderly (≥85 years old). Trends in major amputation and mortality by age group were analyzed. RESULTS: There were 156,513 patients who underwent LER for CLTI. Of these, 9,063 (5.79%) patients had premature PAD, 131,694 (84.14%) patients were 51-84 years old, and 15,756 (10.07%) were elderly. Patients with premature PAD were more likely to have insulin-dependent diabetes, be dialysis-dependent, and be active smokers compared to patients 51-84 years old and the elderly. Elderly patients were more likely to undergo an endovascular procedure for tissue loss compared to younger groups. Perioperative and 1-year major amputation rates were highest among patients with premature PAD and decreased with increasing age (P < 0.001), while perioperative and 1-year mortality increased with age (P < 0.001). On multivariable analysis, premature PAD was associated with an increased risk of major amputation (odds ratio, OR = 1.41 [1.22-1.62]), while elderly age was associated with decreased odds of major amputation compared to patients 51-84 years old (OR = 0.61 [0.51-0.73]). CONCLUSIONS: Patients at the extremes of age have significantly different outcomes after LER for CLTI. Although mortality increases with age, the risk of major amputation decreases. Patients with premature PAD constitute a group of patients with a high risk of perioperative and 1-year major amputation.


Asunto(s)
Procedimientos Endovasculares , Isquemia/cirugía , Extremidad Inferior/irrigación sanguínea , Enfermedad Arterial Periférica/cirugía , Procedimientos Quirúrgicos Vasculares , Edad de Inicio , Anciano , Anciano de 80 o más Años , Envejecimiento , Amputación Quirúrgica , Enfermedad Crónica , Bases de Datos Factuales , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/mortalidad , Femenino , Humanos , Isquemia/diagnóstico por imagen , Isquemia/mortalidad , Isquemia/fisiopatología , Recuperación del Miembro , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/diagnóstico por imagen , Enfermedad Arterial Periférica/mortalidad , Enfermedad Arterial Periférica/fisiopatología , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/efectos adversos , Procedimientos Quirúrgicos Vasculares/mortalidad
9.
Ann Vasc Surg ; 77: 38-46, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34455041

RESUMEN

BACKGROUND: Endovascular treatment of complex common iliac artery (CIA) and internal iliac artery (IIA) aneurysms using iliac branch endoprostheses (IBE) has proven safe and effective. Instructions for use (IFU) require deployment of current IBE technology with the corresponding manufacturer's modular bifurcated aortic endograft. Concomitant aortoiliac occlusive disease, inadequate renal artery-iliac bifurcation length, and unfavorable aortic anatomy preclude on-label IBE deployment. This study aimed to evaluate the technical feasibility and safety of Alternative Endograft Aortoiliac Reconstruction (AEGAR) for branched endovascular treatment of complex iliac artery aneurysms. METHODS: In 7 consecutive patients with CIA or IIA aneurysms, computed tomography angiography (CTA) and center-line reconstruction revealed aortoiliac anatomy incompatible with the current IBE IFU due to inadequate proximal CIA landing zone (n = 7), inadequate renal artery to iliac bifurcation length (n = 2), compromised aortic anatomy (n = 3), or short infrarenal neck <15 mm (n = 1), either alone or in combination. To overcome these restrictions and facilitate IBE deployment, aortoiliac reconstruction was performed using the Endologix AFX, Endologix Ovation limbs or the Medtronic Endurant II platforms (AEGAR technique). All internal iliac artery reconstructions and external iliac artery extensions were performed using the Gore VBX or Viabahn stent grafts. Technical success was defined as successful delivery of all endograft components without migration or endoleak. RESULTS: The mean patient age was 69 years (range 52-82 years; 6 male). Four patients had bilateral CIA aneurysms and 3 patients had unilateral CIA aneurysms (mean diameter 4.3cm; range 2.2-7 cm). There were 13 IIA VBX stent grafts used for a total of 9 IIAs treated with IBE (bilateral IBE = 2 patients). The mean fluoroscopy time was 38.8 min (range 21.3-64.3 min) and the mean contrast volume was 168.5 mL (range 122-226 mL). Technical success was achieved in all patients and there were no perioperative complications. Mean hospital-stay was 2.2 days (range 1-3 days). Follow-up ranged from 82-957 days (mean = 487 days). At last follow-up, all patients were alive without cardiovascular morbidity; and CTA revealed stable or decreased aneurysm size, patent endografts, and no evidence of endoleak or migration. CONCLUSIONS: The AEGAR technique can be used to safely and effectively overcome certain aortoiliac anatomic constraints that preclude use of current IBE technology. We encourage broader use of these alternative endografts in pertinent anatomic configurations.


Asunto(s)
Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/instrumentación , Aneurisma Ilíaco/cirugía , Stents , Anciano , Anciano de 80 o más Años , Implantación de Prótesis Vascular/efectos adversos , Procedimientos Endovasculares/efectos adversos , Estudios de Factibilidad , Femenino , Humanos , Aneurisma Ilíaco/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
10.
Vascular ; 29(1): 116-118, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32698701

RESUMEN

OBJECTIVES: Lower extremity arterial anatomic variations are rare, with duplication of the superficial femoral artery being an extremely uncommon variant with few prior reports in the literature.Methods/Results: We report the case of a 68-year-old male with calf claudication who underwent angiography and was found to have two separate areas of vessel duplication along the superficial femoral artery, which has not previously been described in the literature. CONCLUSION: Although uncommon, recognition of a duplicated superficial femoral artery is important to avoid difficulties and complications that may arise during open or endovascular procedures.


Asunto(s)
Arteria Femoral/anomalías , Claudicación Intermitente/diagnóstico por imagen , Anciano , Tratamiento Conservador , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/fisiopatología , Humanos , Claudicación Intermitente/fisiopatología , Claudicación Intermitente/terapia , Masculino , Flujo Sanguíneo Regional
11.
Planta ; 250(5): 1717-1729, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31414204

RESUMEN

MAIN CONCLUSION: Seed-processing technologies such as polishing and washing enhance crop seed quality by limited removal of the outer layers and by leaching. Combined, this removes chemical compounds that inhibit germination. Industrial processing to deliver high-quality commercial seed includes removing chemical inhibitors of germination, and is essential to produce fresh sprouts, achieve vigorous crop establishment, and high yield potential in the field. Sugar beet (Beta vulgaris subsp. vulgaris var. altissima Doell.), the main sugar source of the temperate agricultural zone, routinely undergoes several processing steps during seed production to improve germination performance and seedling growth. Germination assays and seedling phenotyping was carried out on unprocessed, and processed (polished and washed) sugar beet fruits. Pericarp-derived solutes, known to inhibit germination, were tested in germination assays and their osmolality and conductivity assessed (ions). Abscisic acid (ABA) and ABA metabolites were quantified in both the true seed and pericarp tissue using UPLC-ESI(+)-MS/MS. Physical changes in the pericarp structures were assessed using scanning electron microscopy (SEM). We found that polishing and washing of the sugar beet fruits both had a positive effect on germination performance and seedling phenotype, and when combined, this positive effect was stronger. The mechanical action of polishing removed the outer pericarp (fruit coat) tissue (parenchyma), leaving the inner tissue (sclerenchyma) unaltered, as revealed by SEM. Polishing as well as washing removed germination inhibitors from the pericarp, specifically, ABA, ABA metabolites, and ions. Understanding the biochemistry underpinning the effectiveness of these processing treatments is key to driving further innovations in commercial seed quality.


Asunto(s)
Ácido Abscísico/metabolismo , Beta vulgaris/crecimiento & desarrollo , Reguladores del Crecimiento de las Plantas/metabolismo , Beta vulgaris/fisiología , Bioquímica , Germinación , Semillas/crecimiento & desarrollo , Semillas/fisiología , Espectrometría de Masas en Tándem
12.
Eur Radiol ; 29(6): 3141-3148, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30488110

RESUMEN

OBJECTIVES: To evaluate whether post-contrast cone-beam breast CT (CBBCT) alone is comparable to the current standard of combined pre- and post-contrast CBBCT regarding diagnostic accuracy and superior regarding radiation exposure. MATERIAL AND METHODS: This study included 49 women (61 breasts) with median age 57.9 years and BI-RADS 4/5 lesions diagnosed on mammography/ultrasound in density type c/d breasts. Two radiologists rated post-contrast CBBCT and pre- and post-contrast CBBCT with subtraction images on the BI-RADS scale separately for calculation of inter- and intra-observer agreement and in consensus for diagnostic accuracy assessment. Sensitivity, specificity, and area under the curve (AUC) were compared via McNemar test and DeLong method, respectively. Subtraction imaging misregistration were measured from 1 (no artifacts) to 4 (artifacts with width > 4 mm). RESULTS: A total of 100 lesion (51 malignant; 6 high risk; 43 benign) were included. AUC, sensitivity, and specificity showed no significant differences comparing post-contrast CBBCT alone versus pre- and post-contrast CBBCT (AUC 0.84 vs. 0.83, p = 0.643; sensitivity 0.89 vs. 0.85, p = 0.158; specificity 0.73 vs. 0.76, p = 0.655). Inter- and intra-observer agreement was excellent (intra-class correlation coefficient ICC = 0.76, ICC = 0.83, respectively). Radiation dose was significantly lower for post-contrast CBBCT alone versus pre- and post-contrast CBBCT (median average glandular radiation dose 5.9 mGy vs. 11.7 mGy, p < 0.001). High-degree misregistrations were evident in the majority of subtraction images (level 1/2/3/4 16.9%/27.1%/16.9%/39%), in particular for bilateral exams (3.2%/29.2%/8.3%/58.3%). CONCLUSION: Diagnostic accuracy of post-contrast CBBCT alone is comparable to pre- and post-contrast CBBCT in type c/d breasts, while yielding a significant twofold radiation dose reduction. KEY POINTS: • The diagnostic accuracy of post-contrast CBBCT alone is comparable to dual acquisition of pre- and post-contrast CBBCT. • Acquisition of the post-contrast CBBCT scan alone reduces radiation exposure compared to pre- and post-contrast CBBCT, thus countering one of the main limitations of CBBCT. • High-degree misregistration artifacts limit the interpretation of subtraction images from pre- and post-contrast CBBCT studies.


Asunto(s)
Artefactos , Neoplasias de la Mama/diagnóstico , Mama/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Medios de Contraste/farmacología , Mamografía/métodos , Traumatismos por Radiación/prevención & control , Densidad de la Mama , Femenino , Humanos , Persona de Mediana Edad , Exposición a la Radiación/efectos adversos , Reproducibilidad de los Resultados
13.
Eur Radiol ; 29(3): 1194-1202, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30255249

RESUMEN

PURPOSE: To review the published evidence on cone-beam breast computed tomography (CBBCT) and summarize its diagnostic accuracy for breast lesion assessment. MATERIALS AND METHODS: A systematic literature search was conducted using the EMBASE, MEDLINE and CENTRAL libraries. Studies were included if reporting sensitivity and specificity for discrimination of benign and malignant breast lesions via breast CT. Sensitivity and specificity were jointly modeled using a bivariate approach calculating summary areas under the receiver-operating characteristics curve (AUC). All analyses were separately performed for non-contrast and contrast-enhanced CBBCT (NC-CBBCT, CE-CBBCT). RESULTS: A total of 362 studies were screened, of which 6 with 559 patients were included. All studies were conducted between 2015 and 2018 and evaluated female participants. Four of six studies included dense and very dense breasts with a high proportion of microcalcifications. For NC-CBBCT, pooled sensitivity was 0.789 (95% CI: 0.66-0.89) and pooled specificity was 0.697 (95% CI: 0.471-0.851), both showing considerable significant between-study heterogeneity (I2 = 89.4%, I2 = 94.7%, both p < 0.001). Partial AUC for NC-CBBCT was 0.817. For CE-CBBCT, pooled sensitivity was 0.899 (95% CI: 0.785-0.956) and pooled specificity was 0.788 (95% CI: 0.709-0.85), both exhibiting non-significant moderate between-study heterogeneity (I2 = 57.3%, p = 0.0527; I2 = 53.1%, p = 0.0738). Partial AUC for CE-CBBCT was 0.869. CONCLUSION: The evidence available for CBBCT tends to show superior diagnostic performance for CE-CBBCT over NC-CBBCT regarding sensitivity, specificity and partial AUC. Diagnostic accuracy of CE-CBBCT was numerically comparable to that of breast MRI with meta-analyses reporting sensitivity of 0.9 and specificity of 0.72. KEY POINTS: • CE-CBBCT rather than NC-CBBCT should be used for assessment of breast lesions for its higher diagnostic accuracy. • CE-CBBCT diagnostic performance was comparable to published results on breast MRI, thus qualifying CE-CBBCT as a potential imaging alternative for patients with MRI contraindications.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Mama/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Femenino , Humanos , Curva ROC , Reproducibilidad de los Resultados
14.
Fish Shellfish Immunol ; 85: 3-8, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29410093

RESUMEN

Vaccination is the most effective strategy to control infectious diseases in species with adaptive immunity. In human and in mouse, vaccination typically induces specific memory cells, which can mediate a fast anamnestic response upon infection by the targeted pathogen. In these species, successful vaccination induces a long-lasting protection, long after the titres of specific antibodies and the frequency of specific T cells have returned to steady state. Vaccination is also an important challenge in aquaculture, since alternative treatments are either too costly, or, in the case of antibiotics, are harmful for the environment or may result in dangerous resistances. However, the mechanisms of the long-term protection elicited by vaccines in fish remain poorly understood. Although fish possess typical B- and T-cells expressing diverse repertoires of immunoglobulins and T-cell receptors, many features of antigen specific responses are different from what is known in mouse and in human. Memory is one of the most elusive properties of fish adaptive immunity, and its basis is widely unknown. In this opinion article, we discuss the concept of immune memory in the context of the fish immunity. We illustrate the complexity of this question by discussing the results of experiments showing that protection can be passed through adoptive transfer of leukocytes from vaccinated donor fish to naive histocompatible recipients. Combined with tools developed in Targetfish and in previous projects, such as monoclonal antibodies against B- and T-cell markers, we propose that such models of protection transfer provide excellent systems to dissect the mechanisms of B- and T-cell memory in the future.


Asunto(s)
Traslado Adoptivo , Peces/inmunología , Memoria Inmunológica , Leucocitos/inmunología , Vacunación/veterinaria , Animales
15.
Fish Shellfish Immunol ; 95: 422-439, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31669897

RESUMEN

Cell-mediated cytotoxicity is one of the major mechanisms by which vertebrates control intracellular pathogens. Two cell types are the main players in this immune response, natural killer (NK) cells and cytotoxic T lymphocytes (CTL). While NK cells recognize altered target cells in a relatively unspecific manner CTLs use their T cell receptor to identify pathogen-specific peptides that are presented by major histocompatibility (MHC) class I molecules on the surface of infected cells. However, several other signals are needed to regulate cell-mediated cytotoxicity involving a complex network of cytokine- and ligand-receptor interactions. Since the first description of MHC class I molecules in teleosts during the early 90s of the last century a remarkable amount of information on teleost immune responses has been published. The corresponding studies describe teleost cells and molecules that are involved in CTL responses of higher vertebrates. These studies are backed by functional investigations on the killing activity of CTLs in a few teleost species. The present knowledge on teleost CTLs still leaves considerable room for further investigations on the mechanisms by which CTLs act. Nevertheless the information on teleost CTLs and their regulation might already be useful for the control of fish diseases by designing efficient vaccines against such diseases where CTL responses are known to be decisive for the elimination of the corresponding pathogen. This review summarizes the present knowledge on CTL regulation and functions in teleosts. In a special chapter, the role of CTLs in vaccination is discussed.


Asunto(s)
Citotoxicidad Inmunológica , Peces/inmunología , Linfocitos T Citotóxicos/inmunología , Animales , Citocinas/inmunología , Enfermedades de los Peces/inmunología , Células Asesinas Naturales/inmunología
16.
J Fish Dis ; 42(2): 181-187, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30537062

RESUMEN

The production of piscine viruses, in particular of koi herpesvirus (KHV, CyHV-3) and infectious salmon anaemia virus (ISAV), is still challenging due to the limited susceptibility of available cell lines to these viruses. A number of cell lines from different fish species were compared to standard diagnostic cell lines for KHV and ISAV regarding their capability to exhibit a cytopathic effect (CPE) and to accumulate virus. Two cell lines, so far undescribed, appeared to be useful for diagnostic purposes. Fr994, a cell line derived from ovaries of rainbow trout (Oncorhynchus mykiss), produced constantly high ISA virus (ISAV) titres and developed a pronounced CPE even at high cell passage numbers, while standard cell lines are reported to gradually loose these properties upon propagation. Another cell line isolated from the head kidney of common carp (Cyprinus carpio), KoK, showed a KHV induced CPE earlier than the standard cell line used for diagnostics. A third cell line, named Fin-4, established from the fin epithelium of rainbow trout did not promote efficient replication of tested viruses, but showed antigen sampling properties and might be useful as an in vitro model for virus uptake or phagocytosis.


Asunto(s)
Línea Celular/citología , Enfermedades de los Peces/virología , Herpesviridae/fisiología , Isavirus/fisiología , Replicación Viral , Aletas de Animales/citología , Aletas de Animales/virología , Animales , Carpas/virología , Línea Celular/virología , Femenino , Riñón Cefálico/citología , Riñón Cefálico/virología , Oncorhynchus mykiss/virología , Ovario/citología , Ovario/virología
17.
Eur Radiol ; 28(9): 3731-3741, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29594402

RESUMEN

OBJECTIVES: To evaluate the diagnostic accuracy of contrast-enhanced (CE) cone-beam breast computed tomography (CBBCT) in dense breast tissue and compare it to non-contrast (NC) CBBCT, mammography (MG) and magnetic resonance imaging (MRI). METHODS: This prospective institutional review board-approved study included 41 women (52 breasts) with American College of Radiology (ACR) density types c or d and Breast Imaging Reporting and Data System (BI-RADS) 4 or 5 assessments in MG or ultrasound (US). Imaging modalities were independently evaluated by two blinded readers. RESULTS: A total of 100 lesions (51 malignant, 6 high-risk, and 43 benign) were identified. For readers 1/2, respectively, and p values comparing CE-CBBCT to other modalities: diagnostic accuracy (AUC) for CE-CBBCT was 0.83/0.77, for MRI 0.88/0.89 (p = 0.2272/0.002), for NC-CBBCT 0.73/0.66 (p = 0.038/ 0.0186) and for MG 0.69/0.64 (p = 0.081/0.0207). CE-CBBCT sensitivity (0.88/0.78) was 37-39% higher in comparison to MG (0.49/0.41, p < 0.001 both) but inferior to MRI (0.98/0.96, p = 0.0253/0.0027). CE-CBBCT specificity (0.71/0.71) was numerically higher compared to MRI (0.61/0.69, p = 0.0956/0.7389). CONCLUSIONS: CBBCT diagnostic performance varied with the respective reader and experience. CE-CBBCT improved AUC and sensitivity in comparison to MG and NC-CBBCT, and was comparable to MRI in dense breast tissue. In tendency, specificity was higher for CE-CBBCT than MRI. KEY POINTS: • CE-CBBCT diagnostic accuracy (AUC) was comparable to MRI in dense breasts. • CE-CBBCT improved sensitivity and AUC in comparison to MG and NC-CBBCT. • CE-CBBCT has inferior sensitivity but higher specificity than MRI. • CE-CBBCT is a potential imaging alternative for patients with MRI contraindications.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Medios de Contraste , Imagen por Resonancia Magnética/métodos , Mamografía/métodos , Intensificación de Imagen Radiográfica/métodos , Adulto , Anciano , Mama/diagnóstico por imagen , Mama/patología , Neoplasias de la Mama/patología , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
AJR Am J Roentgenol ; 211(2): W123-W131, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29792725

RESUMEN

OBJECTIVE: The purpose of this study is to evaluate the diagnostic performance of machine learning techniques for malignancy prediction at breast cone-beam CT (CBCT) and to compare them to human readers. SUBJECTS AND METHODS: Five machine learning techniques, including random forests, back propagation neural networks (BPN), extreme learning machines, support vector machines, and K-nearest neighbors, were used to train diagnostic models on a clinical breast CBCT dataset with internal validation by repeated 10-fold cross-validation. Two independent blinded human readers with profound experience in breast imaging and breast CBCT analyzed the same CBCT dataset. Diagnostic performance was compared using AUC, sensitivity, and specificity. RESULTS: The clinical dataset comprised 35 patients (American College of Radiology density type C and D breasts) with 81 suspicious breast lesions examined with contrast-enhanced breast CBCT. Forty-five lesions were histopathologically proven to be malignant. Among the machine learning techniques, BPNs provided the best diagnostic performance, with AUC of 0.91, sensitivity of 0.85, and specificity of 0.82. The diagnostic performance of the human readers was AUC of 0.84, sensitivity of 0.89, and specificity of 0.72 for reader 1 and AUC of 0.72, sensitivity of 0.71, and specificity of 0.67 for reader 2. AUC was significantly higher for BPN when compared with both reader 1 (p = 0.01) and reader 2 (p < 0.001). CONCLUSION: Machine learning techniques provide a high and robust diagnostic performance in the prediction of malignancy in breast lesions identified at CBCT. BPNs showed the best diagnostic performance, surpassing human readers in terms of AUC and specificity.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico/métodos , Aprendizaje Automático , Neoplasias de la Mama/patología , Medios de Contraste , Femenino , Humanos , Yohexol/análogos & derivados , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Interpretación de Imagen Radiográfica Asistida por Computador , Sensibilidad y Especificidad
19.
J Comput Assist Tomogr ; 42(1): 1-5, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28806320

RESUMEN

PURPOSE: The aim of this study was to evaluate the exclusive performance of quality-assured high-resolution breast magnetic resonance imaging (MRI) for early detection of breast cancer in a population of asymptomatic women. MATERIALS AND METHODS: A total of 1189 MRI examinations performed in 789 asymptomatic women (mean age, 51.1 years) were evaluated. All examinations were performed using open bilateral surface coil, dedicated compression device, and high spatial resolution (matrix, 512 × 512). Digital mammography was available for all participants. Assessment included density types, artifact level, and Breast Imaging Reporting and Data System classification. Evaluation was performed by 2 readers. In addition, a computer-assisted diagnosis (CAD) system was used for image assessment. RESULTS: Breast MRI showed density types I and II in 87.6% and artifacts categories III and IV in 3.1%. Study included 32 carcinomas (8 ductal carcinoma in situ, 24 invasive tumors). Both readers detected 29 of 32 correctly (sensitivity 90.6%). The variation between the readers was low (reader 1: specificity, 94.4% and positive predictive value (PPV), 25.7%; reader 2: specificity, 97.6% and PPV, 34.1%). Sensitivity of CAD was 62.5% (specificity, 84.4%; PPV, 5.2%). Digital mammography detected 13 of 32 carcinomas (sensitivity, 56.3%; specificity, 98.4%; PPV, 32.1%). CONCLUSIONS: The exclusive use of quality-assured breast MRI allows the early detection of breast cancer with a high sensitivity and specificity. The CAD analysis of MRI does not give additional information but shows results comparable with digital mammography.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Detección Precoz del Cáncer , Imagen por Resonancia Magnética/métodos , Garantía de la Calidad de Atención de Salud , Artefactos , Densidad de la Mama , Medios de Contraste , Diagnóstico por Computador , Femenino , Gadolinio DTPA , Humanos , Mamografía , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad , Técnica de Sustracción
20.
Phys Rev Lett ; 118(17): 179901, 2017 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-28498693

RESUMEN

This corrects the article DOI: 10.1103/PhysRevLett.118.130404.

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