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1.
J Vasc Interv Radiol ; 35(1): 137-141, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37820885

RESUMEN

Eleven patients (5 men, 6 women) with post-operative thoracic duct injuries and high output chylothorax were treated with thoracic duct embolization (TDE). Six patients underwent intraprocedural thoracic duct ligation at the time of original procedure. In all cases, the pleural fluid demonstrated high triglyceride levels (414 mg/dL; interquartile range [IQR], 345 mg/dL). Median daily (IQR) chest tube outputs before and after TDE were 900 mL (1,200 mL) and 325 mL (630 mL), respectively. Coil- or plug-assisted ethylene vinyl alcohol (EVOH) copolymer was used as embolic agent in all patients. Technical and clinical success rates were 100% and 82%, respectively. Nontarget venous embolization of EVOH copolymer was not identified on subsequent imaging.


Asunto(s)
Quilotórax , Embolización Terapéutica , Traumatismos Torácicos , Masculino , Humanos , Femenino , Quilotórax/diagnóstico por imagen , Quilotórax/etiología , Quilotórax/terapia , Embolización Terapéutica/métodos , Conducto Torácico/diagnóstico por imagen , Estudios Retrospectivos , Traumatismos Torácicos/terapia , Resultado del Tratamiento
2.
Ann Surg Oncol ; 30(2): 804-813, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36344711

RESUMEN

BACKGROUND: Nanoliposomal irinotecan (nal-IRI) is a promising novel hyperthermic intraperitoneal chemotherapy (HIPEC) agent given its enhanced efficacy against gastrointestinal tumors, safety profile, thermo-synergy, and heat stability. This report describes the first in-human phase 1 clinical trial of nal-IRI during cytoreductive surgery (CRS) and HIPEC. METHODS: Patients with peritoneal surface disease (PSD) from appendiceal and colorectal neoplasms were enrolled in a 3 + 3 dose-escalation trial using nal-IRI (70-280 mg/m2) during HIPEC for 30 min at 41 ± 1 °C. The primary outcome was safety. The secondary outcomes were pharmacokinetics (PK) and disease-free survival. Adverse events (AEs) categorized as grade 2 or higher were recorded. The serious AEs (SAEs) were mortality, grade ≥ 3 AEs, and dose-limiting toxicity (DLT). Irinotecan and active metabolite SN38 were measured in plasma and peritoneal washings. RESULTS: The study enrolled 18 patients, who received nal-IRI during HIPEC at 70 mg/m2 (n = 3), 140 mg/m2 (n = 6), 210 mg/m2 (n = 3), and 280 mg/m2 (n = 6). No DLT or mortality occurred. The overall morbidity for CRS/HIPEC was 39% (n = 7). Although one patient experienced neutropenia, no AE (n = 131) or SAE (n = 3) was definitively attributable to nal-IRI. At 280 mg/m2, plasma irinotecan and SN38 measurements showed maximum concentrations of 0.4 ± 0.6 µg/mL and 3.0 ± 2.4 ng/mL, a median time to maximum concentration of 24.5 and 26 h, and areas under the curve of 22.6 h*µg/mL and 168 h*ng/mL, respectively. At the 6-month follow-up visit, 83% (n = 15) of the patients remained disease-free. CONCLUSIONS: In this phase 1 HIPEC trial (NCT04088786), nal-IRI was observed to be safe, and PK profiling showed low systemic absorption overall. These data support future studies testing the efficacy of nal-IRI in CRS/HIPEC.


Asunto(s)
Neoplasias Colorrectales , Hipertermia Inducida , Neoplasias Peritoneales , Humanos , Irinotecán/uso terapéutico , Terapia Combinada , Calor , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Procedimientos Quirúrgicos de Citorreducción/efectos adversos , Neoplasias Colorrectales/patología , Hipertermia Inducida/efectos adversos , Tasa de Supervivencia
3.
J Digit Imaging ; 36(2): 388-394, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36357753

RESUMEN

The study aims to prove that it takes less time to look up relevant clinical history from an electronic medical record (EMR) if the information is already provided in a specific space in the EMR by a fellow radiologist. Patients with complex oncological and surgical histories need frequent imaging, and every time a radiologist may spend a significant amount of time looking up the same clinical information as their peers. In collaboration with ACMIO and Radiant Epic team, a space labeled "Specialty Comments" was added to the SNAPSHOT of patient's chart in EMR. For our research purpose, the specialty comment was labeled as boxed history as a variable for data analysis. If the history was not provided in that particular space, it was labeled as without boxed history. Inclusion criteria included outpatients with complex oncological histories undergoing CT chest, abdomen, and pelvis with IV contrast. The time to look up history (LUT) was documented in minutes and seconds. Two assistant professors from Abdominal Imaging provided LUT. A total of 85 cases were included in the study, 39 with boxed history and 46 without boxed history. Comparing averages of the individual reader means for history, mean LUT differed by 2.03 min (without boxed history) versus 0.57 min (with boxed history), p < 0.0001. The t-test and the nonparametric Wilcoxon tests for a difference in the population means were highly significant (p < 0.0001). A history directed to radiologist's needs resulted in a statistically significant decrease in time spent by interpreting radiologists to look through the electronic medical records for patients with complex oncological histories. Availability of history pertinent to radiology has wide-ranging advantages, including quality reporting, decrease in turnaround time, reduction in interpretation errors, and radiologists' continued learning. The space for documenting clinical history may be reproduced, or some similar area may be developed by optimizing the electronic medical records.


Asunto(s)
Registros Electrónicos de Salud , Radiología , Humanos , Radiólogos , Tomografía Computarizada por Rayos X , Abdomen
4.
J Hand Surg Am ; 47(11): 1115.e1-1115.e7, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-34686395

RESUMEN

PURPOSE: The hand has unique skin characteristics. Intrinsic flap donors are limited due to functional specificity and compactly connected structures. The hypothenar area is a reliable option for the reconstruction of finger defects. We performed anatomic studies elucidating the blood supply of this area and hypothesized that the fourth common palmar digital artery perforator free flap can be used to reconstruct soft tissue defects in fingers with minimal donor site morbidity. METHODS: From November 2017 to February 2020, 30 procedures of fourth common digital artery perforator free flaps were performed to cover digital skin defects. A retrospective chart review was performed, and the cases were analyzed. RESULTS: The mean patient age was 42.4 years (range, 1-75 years; median age, 40 years). Defects were located at the fingertip (n = 12), the dorsum (n = 3), the palmar (n = 9) aspect of the finger, and both the dorsal and palmar aspects of the finger (n = 6). Indications included emergent coverage (n = 13), coverage after necrosis (n = 11), oncological resection (n = 1), and contracture release (n = 5). The defect size ranged from 1.5 × 0.8 cm (1.2 cm2) to 6 × 2.5 cm (15 cm2). The perforator was located approximately 1 cm proximal to the distal palmar crease as it arose from the fourth common digital artery at a right angle. It continued to the ulnar border of the hand through the superficial fascia of the hypothenar muscles before running in a proximoulnar direction toward the dorsum of the hand. The diameter of the perforator was between 0.5 and 0.7 mm. All flaps survived. One case required a split-thickness skin graft for donor site closure, and all others could be closed primarily. CONCLUSIONS: The fourth common digital artery perforator is a versatile flap and can be used for both palmar and dorsal defects, including for the fingertip. The location of the perforator used differs from previous descriptions but is routinely and reliably located. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.


Asunto(s)
Traumatismos de los Dedos , Colgajo Perforante , Procedimientos de Cirugía Plástica , Traumatismos de los Tejidos Blandos , Humanos , Adulto , Lactante , Preescolar , Niño , Adolescente , Adulto Joven , Persona de Mediana Edad , Anciano , Traumatismos de los Dedos/cirugía , Estudios Retrospectivos , Procedimientos de Cirugía Plástica/métodos , Traumatismos de los Tejidos Blandos/cirugía , Arteria Cubital/cirugía , Trasplante de Piel/métodos , Resultado del Tratamiento
5.
Br J Cancer ; 123(3): 495, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32393850

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

6.
Chaos ; 30(5): 051102, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32491902

RESUMEN

Phase transitions (PTs) are generally classified into second-order and first-order transitions, each exhibiting different intrinsic properties. For instance, a first-order transition exhibits latent heat and hysteresis when a control parameter is increased and then decreased across a transition point, whereas a second-order transition does not. Recently, hybrid percolation transitions (HPTs) are issued in diverse complex systems, in which the features of first-order and second-order PTs occur at the same transition point. Thus, the question whether hysteresis appears in an HPT arises. Herein, we investigate this fundamental question with a so-called restricted Erdos-Rényi random network model, in which a cluster fragmentation process is additionally proposed. A hysteresis curve of the order parameter was obtained. Depending on when the reverse process is initiated, the shapes of hysteresis curves change, and the critical behavior of the HPT is conserved throughout the forward and reverse processes.

7.
Br J Cancer ; 120(1): 88-96, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30377341

RESUMEN

BACKGROUND: Pancreatic cancer (PC) hijacks innate cellular processes to promote cancer growth. We hypothesized that PC exploits PD-1/PD-L1 not only to avoid immune responses, but to directly enhance growth. We also hypothesized that immune checkpoint inhibitors (ICIs) have direct cytotoxicity in PC. We sought to elucidate therapeutic targeting of PD-1/PD-L1. METHODS: PD-1 was assessed in PC cells, patient-derived organoids (PDOs), and clinical tissues. Then, PC cells were exposed to PD-L1 to evaluate proliferation. To test PD-1/PD-L1 signaling, cells were exposed to PD-L1 and MAPK was examined. Radio-immunoconjugates with anti-PD-1 drugs were developed to test uptake in patient-derived tumor xenografts (PDTXs). Next, PD-1 function was assessed by xenografting PD-1-knockdown cells. Finally, PC models were exposed to ICIs. RESULTS: PD-1 expression was demonstrated in PCs. PD-L1 exposure increased proliferation and activated MAPK. Imaging PDTXs revealed uptake of radio-immunoconjugates. PD-1 knockdown in vivo revealed 67% smaller volumes than controls. Finally, ICI treatment of both PDOs/PDTXs demonstrated cytotoxicity and anti-MEK1/2 combined with anti-PD-1 drugs produced highest cytotoxicity in PDOs/PDTXs. CONCLUSIONS: Our data reveal PCs innately express PD-1 and activate druggable oncogenic pathways supporting PDAC growth. Strategies directly targeting PC with novel ICI regimens may work with adaptive immune responses for optimal cytotoxicity.


Asunto(s)
Antígeno B7-H1/inmunología , Inmunoterapia , Neoplasias Pancreáticas/tratamiento farmacológico , Receptor de Muerte Celular Programada 1/inmunología , Animales , Antígeno B7-H1/antagonistas & inhibidores , Proliferación Celular/efectos de los fármacos , Femenino , Humanos , Masculino , Ratones , Organoides/efectos de los fármacos , Organoides/inmunología , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/patología , Cultivo Primario de Células , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
8.
Chaos ; 29(9): 091102, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31575135

RESUMEN

Understanding of a hybrid percolation transitions (HPTs) induced by cluster coalescence, exhibiting a jump in the giant cluster size and a critical behavior of finite clusters, is fundamental and intriguing. Here, we uncover the underlying mechanism using the so-called restricted-random network model, in which clusters are ranked by size and partitioned into small- and large-cluster sets. As clusters are merged and their rankings are updated, they may move back and forth across the set boundary. The intervals of these crossings exhibit a self-organized critical (SOC) behavior with two power-law exponents. During this process, a bump is formed and eliminated in the cluster size distribution, characterizing the criticality of the HPT. This SOC behavior is in contrast to the critical branching process, which governs the avalanche dynamics of the HPT in the pruning process. Finally, we find that a burst of such crossing events occurs and signals the upcoming abrupt transition.

10.
BMC Health Serv Res ; 16(1): 504, 2016 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-27655007

RESUMEN

BACKGROUND: Despite universal population coverage and equity being a stated policy goal of its NHIS, over a decade since passage of the first law in 2003, Ghana continues to struggle with how to attain it. The predominantly (about 70 %) tax funded NHIS currently has active enrolment hovering around 40 % of the population. This study explored in-depth enablers and barriers to enrolment in the NHIS to provide lessons and insights for Ghana and other low and middle income countries (LMIC) into attaining the goal of universality in Universal Health Coverage (UHC). METHODS: We conducted a cross sectional mixed methods study of an urban and a rural district in one region of Southern Ghana. Data came from document review, analysis of routine data on enrolment, key informant in-depth interviews with local government, regional and district insurance scheme and provider staff and community member in-depth interviews and focus group discussions. RESULTS: Population coverage in the NHIS in the study districts was not growing towards near universal because of failure of many of those who had ever enrolled to regularly renew annually as required by the NHIS policy. Factors facilitating and enabling enrolment were driven by the design details of the scheme that emanate from national level policy and program formulation, frontline purchaser and provider staff implementation arrangements and contextual factors. The factors inter-related and worked together to affect client experience of the scheme, which were not always the same as the declared policy intent. This then also affected the decision to enrol and stay enrolled. CONCLUSIONS: UHC policy and program design needs to be such that enrolment is effectively compulsory in practice. It also requires careful attention and responsiveness to actual and potential subscriber, purchaser and provider (stakeholder) incentives and related behaviour generated at implementation levels.

11.
BMC Cancer ; 14: 242, 2014 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-24708527

RESUMEN

BACKGROUND: Although breast cancer frequently metastasizes to the bones and brain, rarely breast cancer patients may develop isolated liver metastasis. There is increasing data that anti-HER2 targeted therapy in conjunction with systemic chemotherapy may lead to increased rates of pathologic complete response in the primary breast cancer. However, little is known about its effects on metastatic liver disease. CASE PRESENTATION: We report the treatment of a 54-year-old female who was diagnosed with HER2-positive invasive ductal carcinoma and synchronous breast cancer liver metastasis (BCLM). The patient underwent eight cycles of standard docetaxel with two anti-HER2 targeted agents, trastuzumab and pertuzumab. Subsequent radiographic imaging demonstrated complete radiographic response in the primary lesion with an approximate 75% decrease in the liver metastasis. After informed consent the patient underwent modified radical mastectomy that revealed pathologic complete response. Re-staging demonstrated no new disease outside the liver and a left hepatectomy was performed for resection of BCLM. Final pathologic examination revealed no residual malignant cells in the liver specimen, indicating pathologic complete response. Herein, we discuss the anti-HER2 targeted agents trastuzumab and pertuzumab and review the data on dual HER2 antagonism for HER2-positive breast cancer and the role of surgical resection of BCLM. CONCLUSIONS: The role of targeted agents for metastatic HER2-positive breast cancer is under active clinical trial investigation and we await the maturation of trial results and long-term survival data. Our results suggest that these agents may also be effective for producing considerable pathologic response in patients with BCLM.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Receptor ErbB-2/genética , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Ensayos Clínicos como Asunto , Femenino , Humanos , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Persona de Mediana Edad , Terapia Molecular Dirigida , Receptor ErbB-2/antagonistas & inhibidores , Trastuzumab
12.
bioRxiv ; 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38352391

RESUMEN

We report a functional pipeline for facile conversion of variable Fv domains, typically discovered in antibody discovery programs, into chimeric monoclonal antibodies (mAbs). Often, in initial screenings, a set of candidate mAbs is produced in small volumes and purified from supernatant for testing. Our pipeline also simplifies purification of mAbs by using an extended histidine tag (His-10) fused to the C-terminus of the light chain. Both the length of the His-10 and its location have been shown to affect the efficacy of mAb purification using an inexpensive nickel-based resin at neutral pH. Our antibody cloning and purification pipeline, when followed together with detection and affinity measurements, can be smoothly incorporated into an antibody discovery workflow.

13.
Front Pharmacol ; 14: 1197549, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38074125

RESUMEN

Background: Everolimus is an inhibitor of mammalian target of rapamycin complex 1. As mutations in TSC1 and TSC2, which cause partial-onset seizures associated with TSC, were found in focal cortical dysplasia type Ⅱ (FCD Ⅱ) patients, a clinical trial has been performed to explore the efficacy and safety of everolimus in FCD patients. However, no dosage regimen was determined to treat FCD II. To recommend an optimal dose regimen for FCD patients, a population pharmacokinetic model of everolimus in FCD patients was developed. Methods: The data of everolimus were collected from September 2017 to May 2020 in a tertiary-level hospital in Korea. The model was developed using NONMEM® software version 7.4.1 (Icon Development Solutions, Ellicott City, MD, United States). Results: The population pharmacokinetics of everolimus was described as the one-compartment model with first-order absorption, with the effect of BSA on clearance. The final model was built as follows: TVCL = 12.5 + 9.71 × (BSA/1.5), TVV = 293, and TVKA = 0.585. As a result of simulation, a dose higher than 7 mg/m2 is needed in patients with BSA 0.5 m2, and a dose higher than 6 mg/m2 is needed in patients with BSA 0.7 m2. A dose of 4.5 mg/m2 is enough in the population with BSA higher than 1.5 m2 to meet the target trough range of 5-15 ng/mL. Conclusion: Based on the developed pharmacokinetics model, the optimal dose of everolimus in practice was recommended by considering the available strengths of Afinitor disperz®, 2 mg, 3 mg, and 5 mg.

14.
Nucl Med Commun ; 44(12): 1151-1155, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37901917

RESUMEN

OBJECTIVE: Human epidermal growth factor receptor 2 (HER2) is an important biomarker for targeted gastric cancer (GC) immunotherapy. However, heterogeneous HER2 overexpression in GC, loss of HER2 expression during therapy, and inability to non-invasively identify HER2 overexpressing tumors impede effective targeting therapies. Improved HER2-specific functional imaging can address these challenges. Trastuzumab is a HER2-directed mAb to treat HER2 overexpressing cancers. The 64 Cu-DOTA-trastuzumab radiotracer is used to detect HER2+ metastatic breast cancer. We aimed to develop 64 Cu-DOTA-trastuzumab PET-CT to detect and characterize tumor uptake in HER2+ or - GC patients. METHODS: We conducted a single-arm phase II pilot study exploring the feasibility of 64 Cu-DOTA-trastuzumab for PET imaging of HER2 overexpressing GC compared to HER2 non-expressing tumors. Eight patients with biopsy-confirmed gastric adenocarcinoma were included. Immunohistochemistry was used to evaluate primary tumor biopsies for HER2 overexpression. Patients were injected with 45 mg of cold trastuzumab followed by 5 mg of 64 Cu-DOTA-trastuzumab. PET-CT scans were performed 24-48 h post radiotracer injection and compared to standard staging CT scans. RESULTS: We observed limited toxicity following 64 Cu-DOTA-trastuzumab injections. While there was uptake of the radiotracer in portions of HER2+ lesions, there was no statistically significant distinction between tumor and background by standardized uptake value analysis. CONCLUSION: Despite the potential of 64 Cu-DOTA-trastuzumab PET imaging of HER2+ metastatic breast cancer, a 5 mg dose of this radiotracer injected 24-48 h before imaging was insufficient to identify HER2+ GC. These results inform future GC imaging studies to optimize biomarker-targeted therapies based on dosage and timing for more clinically relevant imaging.


Asunto(s)
Neoplasias de la Mama , Neoplasias Gástricas , Humanos , Femenino , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Proyectos Piloto , Neoplasias Gástricas/diagnóstico por imagen , Trastuzumab , Receptor ErbB-2/metabolismo , Tomografía de Emisión de Positrones/métodos , Neoplasias de la Mama/patología
15.
Anticancer Res ; 42(2): 911-917, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35093889

RESUMEN

BACKGROUND/AIM: To identify the imaging and clinical features of hepatic neuroendocrine tumors (NETs) associated with peritumoral hyperintensity in the hepatobiliary phase of gadoxetic acid-enhanced magnetic resonance (MR) imaging. PATIENTS AND METHODS: Fifty-seven patients with hepatic NETs were enrolled. Based on the degree of peritumoral hyperintensity, patients were divided into three groups: group 0 (no peritumoral hyperintensity), group 1 (lower peritumoral hyperintensity), and group 2 (higher peritumoral hyperintensity). The imaging and clinical findings were compared among the three groups. RESULTS: Apparent diffusion coefficient (ADC) values of group 2 were significantly lower than those of group 0 and group 1. Atypical (cholangiocarcinoma-like) enhancement pattern in the arterial phase was significantly more frequently observed in group 2 as compared to that in group 0 and group 1. Group 2 patients showed significantly poorer progression-free survival than group 0 patients. CONCLUSION: Hepatic NETs with greater peritumoral hyperintensity exhibit greater malignant potential.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Neoplasias Hepáticas/diagnóstico por imagen , Tumores Neuroendocrinos/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Diagnóstico Diferencial , Femenino , Gadolinio DTPA , Humanos , Aumento de la Imagen , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/patología , Supervivencia sin Progresión
16.
J Nucl Med ; 63(8): 1145-1148, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34857660

RESUMEN

We hypothesized that functional imaging with 64Cu-DOTA-trastuzumab PET/CT would predict the response to the antibody-drug conjugate trastuzumab-emtansine (T-DM1). Methods: Ten women with metastatic human epidermal growth factor receptor 2-positive breast cancer underwent 18F-FDG PET/CT and 64Cu-DOTA-trastuzumab PET/CT on days 1 and 2 before treatment with T-DM1. Results: T-DM1-responsive patients had higher uptake than nonresponsive patients. Day 1 minimum SUVmax (5.6 vs. 2.8, P < 0.02), day 2 minimum SUVmax (8.1 vs. 3.2, P < 0.01), and day 2 average SUVmax (8.5 vs. 5.4, P < 0.05) for 64Cu-DOTA-trastuzumab all favored responding patients. Tumor-level response suggested threshold dependence on SUVmax Patients with a day 2 minimum SUVmax above versus below the threshold had a median time to treatment failure of 28 mo versus 2 mo (P < 0.02). Conclusion: Measurement of trastuzumab uptake in tumors via PET/CT is promising for identifying patients with metastatic breast cancer who will benefit from T-DM1.


Asunto(s)
Neoplasias de la Mama , Ado-Trastuzumab Emtansina , Anticuerpos Monoclonales Humanizados/uso terapéutico , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Femenino , Compuestos Heterocíclicos con 1 Anillo , Humanos , Proyectos Piloto , Tomografía Computarizada por Tomografía de Emisión de Positrones , Receptor ErbB-2/metabolismo , Trastuzumab/uso terapéutico
17.
Phys Rev E ; 101(5-1): 052313, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32575195

RESUMEN

The Kuramoto model exhibits different types of synchronization transitions depending on the type of natural frequency distribution. To obtain these results, the Kuramoto self-consistency equation (SCE) approach has been used successfully. However, this approach affords only limited understanding of more detailed properties such as the stability. Here we extend the SCE approach by introducing an effective potential, that is, an integral version of the SCE. We examine the landscape of this effective potential for second-order, first-order, and hybrid synchronization transitions in the thermodynamic limit. In particular, for the hybrid transition, we find that the minimum of effective potential displays a plateau across the region in which the order parameter jumps. This result suggests that the effective potential can be used to determine a type of synchronization transition.

18.
J Vasc Interv Radiol ; 20(7 Suppl): S505-22, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19560036

RESUMEN

The characterization of human diseases by their underlying molecular and genomic aberrations has been the hallmark of molecular medicine. From this, molecular imaging has emerged as a potentially revolutionary discipline that aims to visually characterize normal and pathologic processes at the cellular and molecular levels within the milieu of living organisms. Molecular imaging holds promise to provide earlier and more precise disease diagnosis, improved disease characterization, and timely assessment of therapeutic response. This primer is intended to provide a broad overview of molecular imaging with specific focus on future clinical applications relevant to interventional radiology.

19.
Int J Radiat Oncol Biol Phys ; 105(3): 659-663, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31271822

RESUMEN

PURPOSE: Response assessment with computed tomography after stereotactic body radiation therapy (SBRT) for non-small cell lung cancer (NSCLC) is challenging because myriad anatomic changes can occur after treatment. Diffusion-weighted magnetic resonance imaging (MRI) may provide additional data to guide therapy response. The primary objective was to evaluate the effect of SBRT on the mean apparent diffusion coefficient (ADC). METHODS AND MATERIALS: This is a prospective clinical study of patients with NSCLC who received SBRT to the primary lung lesion. Patients underwent MRI scans before and at 1 month after completion of SBRT. MRI consisted of T1- and T2-weighted sequences, along with postcontrast, dynamic-contrast, and diffusion-weighted sequences with construction of ADC maps. Two blinded radiologists generated the ADC. SBRT was given over 5 fractions. RESULTS: A total of 13 patients were enrolled. Twelve patients were eligible for analysis. An average increase of 50% and 46% in mean single-plane ADC was observed after treatment by readers 1 and 2, respectively (P < .01, both reviewers). There was good interobserver agreement of single-plane ADC values between the 2 radiologists (Pearson correlation of 0.85 [baseline] and 0.89 [1-month post-SBRT], P < .001 for both). There was also a significant 18% increase in mean volumetric ADC on the 1-month scan (Wilcoxon P = .02). Two patients developed a local failure after SBRT, 1 at 6 months and the other at 34 months. Using a threshold of volumetric ADC increase of greater than 40%, 2 of 2 patients demonstrated local failure compared with 0 of 10 patients below this limit. CONCLUSIONS: A statistically significant increase in ADC was observed 1 month after treatment. An ADC increase of 40% at 1 month was associated with a higher rate of local failure. This pilot study provides impetus for studying ADC as a radiomic biomarker in patients receiving lung SBRT for NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Imagen de Difusión por Resonancia Magnética/métodos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/radioterapia , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/patología , Medios de Contraste , Imagen de Difusión por Resonancia Magnética/estadística & datos numéricos , Humanos , Neoplasias Pulmonares/patología , Recurrencia Local de Neoplasia , Variaciones Dependientes del Observador , Proyectos Piloto , Tomografía de Emisión de Positrones , Estudios Prospectivos , Radiocirugia , Estadísticas no Paramétricas , Factores de Tiempo , Tomografía Computarizada por Rayos X , Carga Tumoral
20.
Phys Rev E ; 97(2-1): 020203, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29548084

RESUMEN

The Kuramoto model with mixed signs of couplings is known to produce a traveling-wave synchronized state. Here, we consider an abrupt synchronization transition from the incoherent state to the traveling-wave state through a long-lasting metastable state with large fluctuations. Our explanation of the metastability is that the dynamic flow remains within a limited region of phase space and circulates through a few active states bounded by saddle and stable fixed points. This complex flow generates a long-lasting critical behavior, a signature of a hybrid phase transition. We show that the long-lasting period can be controlled by varying the density of inhibitory/excitatory interactions. We discuss a potential application of this transition behavior to the recovery process of human consciousness.

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