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2.
Insights Imaging ; 13(1): 109, 2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35767122

RESUMEN

BACKGROUND: Interventional radiological procedures have significantly increased in recent years. Most of them are minimally invasive and require a short hospitalization, mainly done in other non-radiological units nowadays. Limited bed availability and high occupancy rates in these units create longer waiting lists and cancellations. The aim of this retrospective study is to assess the creation and functioning of a Radiology Day Unit (RDU) and evaluating its outcomes. For this purpose, data about interventional procedures and its complications, incidents, patient safety, quality and satisfaction rates were collected from May 2018 to December 2020, and posteriorly analyzed to evaluate its implementation. RESULTS: During the assessed period, 3841 patients were admitted into the RDU, with a net increase of 13% and 26% in the second and third year, respectively. Procedures performed by the Abdominal Radiology section were the most frequent (76-85%) followed by Interventional Vascular Radiology and Thoracic Radiology. Complication rates were low (1.5%) and most of them were self-limited and managed in the own department. Waiting lists were significantly reduced, from 2 months to 1 week in case of procedures performed by the Abdominal Radiology section. Patient satisfaction was higher than 80% in all the items evaluated with a global satisfaction of 93%. CONCLUSION: The RDU in our hospital has become a vital section for the management and post-procedure caring of patients undergoing interventional procedures in the Radiology Service with low complication rates and overall high levels of quality and patient safety, allowing the reduction of waiting lists and occupancy rates.

3.
Adv Lab Med ; 3(4): 342-360, 2022 Dec.
Artículo en Inglés, Español | MEDLINE | ID: mdl-37363428

RESUMEN

Objectives: The central nervous system (CNS) is essential for homeostasis and controls the physiological functions of the body. However, the biochemical characteristics of the CNS make it especially vulnerable to oxidative damage (OS). This phenomenon compromises correct CNS functioning, leading to neurodegeneration and neuronal death. Contents: OS plays a crucial role in the physiopathology of neurodegenerative diseases. It is involved in multiple mechanisms of nucleic acid, protein, and lipid oxidation, thereby contributing to progressive brain damage. These mechanisms include mitochondrial dysfunction; excessive production of reactive oxygen and nitrogen species; deficiency of antioxidant defenses; protein oligomerization; cytokine production and inflammatory response; blood-brain barrier abnormalities; and proteasome dysfunction. All these dysfunctions are involved in the pathogenesis of neurodegenerative diseases, including Parkinson's disease, Alzheimer's disease, Huntington's disease, or amyotrophic lateral sclerosis. Summary and outlook: A curative treatment is currently not available. Research is focused on the search for therapies that reduce oxidative damage and delay disease progression. In the recent years, researchers have focused their attention on the effects of antioxidant therapies.

5.
Front Med (Lausanne) ; 8: 815732, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35096906

RESUMEN

Background: Interstitial lung sequelae are increasingly being reported in survivors of COVID-19 pneumonia. An early detection of these lesions may help prevent the development of irreversible lung fibrosis. Lung ultrasound (LUS) has shown high diagnostic accuracy in interstitial lung disease (ILD) and could likely be used as a first-line test for post-COVID-19 lung sequelae. Methods: Single-center observational prospective study. Follow-up assessments of consecutive patients hospitalized for COVID-19 pneumonia were conducted 2-5 months after the hospitalization. All patients underwent pulmonary function tests (PFTs), high-resolution computed tomography (HRCT), and LUS. Radiological alterations in HRCT were quantified using the Warrick score. The LUS score was obtained by evaluating the presence of pathological B-lines in 12 thoracic areas (range, 0-12). The correlation between the LUS and Warrick scores was analyzed. Results: Three hundred and fifty-two patients who recovered from COVID-19 pneumonia were recruited between July and September 2020. At follow-up, dyspnea was the most frequent symptom (69.3%). FVC and DLCO alterations were present in 79 (22.4%) and 234 (66.5%) patients, respectively. HRCT showed relevant interstitial lung sequelae (RILS) in 154 (43.8%) patients (Warrick score ≥ 7). The LUS score was strongly correlated with the HRCT Warrick score (r = 0.77) and showed a moderate inverse correlation with DLCO (r = -0.55). The ROC curve analysis revealed that a LUS score ≥ 3 indicated an excellent ability to discriminate patients with RILS (sensitivity, 94.2%; specificity, 81.8%; negative predictive value, 94.7%). Conclusions: LUS could be implemented as a first-line procedure in the evaluation of Post-COVID-19 interstitial lung sequelae. A normal LUS examination rules out the presence of these sequelae in COVID-19 survivors, avoiding the need for additional diagnostic tests such as HRCT.

7.
Materials (Basel) ; 13(21)2020 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-33142888

RESUMEN

As optoelectronic devices continue to improve, control over film thickness has become crucial, especially in applications that require ultra-thin films. A variety of undesired effects may arise depending on the specific growth mechanism of each material, for instance a percolation threshold thickness is present in Volmer-Webber growth of materials such as silver. In this paper, we explore the introduction of aluminum in silver films as a mechanism to grow ultrathin metallic films of high transparency and low sheet resistance, suitable for many optoelectronic applications. Furthermore, we implemented such ultra-thin metallic films in Dielectric/Metal/Dielectric (DMD) structures based on Aluminum-doped Zinc Oxide (AZO) as the dielectric with an ultra-thin silver aluminum (Ag:Al) metallic interlayer. The multilayer structures were deposited by magnetron sputtering, which offers an industrial advantage and superior reliability over thermally evaporated DMDs. Finally, we tested the optimized DMD structures as a front contact for n-type silicon solar cells by introducing a hole-selective vanadium pentoxide (V2O5) dielectric layer.

8.
J Synchrotron Radiat ; 26(Pt 2): 393-405, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30855248

RESUMEN

MXCuBE2 is the second-generation evolution of the MXCuBE beamline control software, initially developed and used at ESRF - the European Synchrotron. MXCuBE2 extends, in an intuitive graphical user interface (GUI), the functionalities and data collection methods available to users while keeping all previously available features and allowing for the straightforward incorporation of ongoing and future developments. MXCuBE2 introduces an extended abstraction layer that allows easy interfacing of any kind of macromolecular crystallography (MX) hardware component, whether this is a diffractometer, sample changer, detector or optical element. MXCuBE2 also works in strong synergy with the ISPyB Laboratory Information Management System, accessing the list of samples available for a particular experimental session and associating, either from instructions contained in ISPyB or from user input via the MXCuBE2 GUI, different data collection types to them. The development of MXCuBE2 forms the core of a fruitful collaboration which brings together several European synchrotrons and a software development factory and, as such, defines a new paradigm for the development of beamline control platforms for the European MX user community.

9.
Insights Imaging ; 8(2): 271-277, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28197882

RESUMEN

OBJECTIVES: The aim of this report is to identify the radiological findings of unilateral tuberculous lung destruction (UTLD). MATERIALS AND METHODS: Thirteen patients with (UTLD) were reviewed from 1999 to 2014. Only patients with radiological evidence of absence of pulmonary parenchyma preserved were included. Clinical and demographic data were obtained and radiological studies (chest radiograph and CT) were retrospectively reviewed. RESULTS: The left lung was more commonly involved (85%). The following radiological findings were found in all cases: a decrease in the diameter of the pulmonary vessels of the affected lung, herniation of the contralateral lung and hypertrophy of the ribs and/or thickening of extrapleural fat. Two radiological patterns were identified: UTLD with cystic bronchiectasis (85%) and UTLD without residual cystic bronchiectasis (15%). Forty-six per cent of cases had respiratory infection symptoms with presence of air-fluid levels in the affected lung as the most common finding in these patients. CONCLUSIONS: Total unilateral post-tuberculous lung destruction is an irreversible complication with the following main radiological features: predominantly left-sided location, decreases in the diameter of the ipsilateral pulmonary vessels, herniation of the contralateral lung and hypertrophy of the ribs and/or thickening of extrapleural fat. TEACHING POINTS: • Unilateral tuberculous lung destruction is an irreversible complication of tuberculosis. • Left-side predominance and herniation of the contralateral lung are characteristic. • Decreased diameter of the ipsilateral pulmonary vessels occurred in all patients. • The pattern with residual cystic bronchiectasis is the most frequent. • Superimposed non-tuberculous infections may affect the destroyed lung.

10.
Eur Radiol ; 27(2): 821-830, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27271922

RESUMEN

OBJECTIVES: To demonstrate non-inferiority of iobitridol 350 for coronary CT angiography (CTA) compared to higher iodine content contrast media regarding rate of patients evaluable for the presence of coronary artery stenoses. METHODS: In this multicentre trial, 452 patients were randomized to receive iobitridol 350, iopromide 370 or iomeprol 400 and underwent coronary CTA using CT systems with 64-detector rows or more. Two core lab readers assessed 18 coronary segments per patient regarding image quality (score 0 = non diagnostic to 4 = excellent quality), vascular attenuation, signal and contrast to noise ratio (SNR, CNR). Patients were considered evaluable if no segment had a score of 0. RESULTS: Per-patient, the rate of fully evaluable CT scans was 92.1, 95.4 and 94.6 % for iobitridol, iopromide and iomeprol, respectively. Non-inferiority of iobitridol over the best comparator was demonstrated with a 95 % CI of the difference of [-8.8 to 2.1], with a pre-specified non-inferiority margin of -10 %. Although average attenuation increased with higher iodine concentrations, average SNR and CNR did not differ between groups. CONCLUSIONS: With current CT technology, iobitridol 350 mg iodine/ml is not inferior to contrast media with higher iodine concentrations in terms of image quality for coronary stenosis assessment. KEY POINTS: • Iodine concentration is an important parameter for image quality in coronary CTA. • Contrast enhancement must be balanced against the amount of iodine injected. • Iobitridol 350 is non-inferior compared to CM with higher iodine concentrations. • Higher attenuation with higher iodine concentrations, but no SNR or CNR differences.


Asunto(s)
Calcinosis/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Estenosis Coronaria/diagnóstico por imagen , Adulto , Anciano , Medios de Contraste , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Método Doble Ciego , Femenino , Humanos , Yodo , Yohexol/análogos & derivados , Yopamidol/análogos & derivados , Masculino , Persona de Mediana Edad , Tomografía Computarizada Multidetector/métodos , Tomografía Computarizada por Rayos X/métodos
12.
Br J Radiol ; 89(1062): 20150824, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26986457

RESUMEN

OBJECTIVE: This study assessed the toxicity and clinical outcomes of three-dimensional (3D) hypofractionated radiotherapy (HFRT) for medically inoperable T1-3 N0-1 non-small-cell lung cancer (NSCLC). METHODS: 34 patients with inoperable early-stage NSCLC were treated from August 2008 to April 2013. Prior to enrolment, patients were required to be evaluated by an experienced thoracic surgeon to determine the "operability". All received 57 Gy in 19 fractions followed by escalated doses of 3-Gy fractions, up to a total dose of 66 Gy using a 3D conformal technique. Toxicities were measured using the Common Terminology Criteria for Adverse Effects v. 4.0. RESULTS: The median follow-up was 33 months (7-74 months). Toxicity grades ≥3 were not observed. Local control (LC) was 80.4% at 2 years, whereas regional control (RC) was 78%. The overall survival (OS), time to progression (TTP) and time to distant metastasis (TTM) at 2 years were 60%, 59% and 80%, respectively. For patients with T1-2 N0 and a tumour size <45 mm (n = 19), rates of OS, TTP and TTM at 2 years were 71%, 75% and 94%, respectively. LC and RC at 2 years were 85% and 94%, respectively. CONCLUSION: HFRT using 3.0-Gy fractions amounting to a total dose of 66 Gy is the recommended dose. A Phase 2 trial is warranted in order to assess the safety and efficacy of this fractionation scheme. ADVANCES IN KNOWLEDGE: HFRT results in a favourable outcome in early-stage lung cancer without the usual restrictions in tumour size and/or location associated with previous treatment methods. No special equipment is required, therefore permitting its application in any centre.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/radioterapia , Hipofraccionamiento de la Dosis de Radiación , Radioterapia Conformacional/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Femenino , Humanos , Estudios Longitudinales , Neoplasias Pulmonares/cirugía , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Traumatismos por Radiación/etiología , Traumatismos por Radiación/prevención & control , Radioterapia Conformacional/efectos adversos , Resultado del Tratamiento
13.
Lung ; 193(6): 993-1000, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26423784

RESUMEN

BACKGROUND: Pleurofibrinolysis has been reported to be potentially beneficial in the management of complicated parapneumonic effusions (CPPE) and empyemas in the adult population. METHODS: Prospective, controlled, randomized, and double-blind study, to evaluate intrapleural alteplase 10 mg (initially 20 mg was considered but bleeding events forced dose reduction) versus 100,000 UI urokinase every 24 h for a maximum of 6 days in patients with CPPE or empyemas. The primary aim was to evaluate the success rate of each fibrinolytic agent at 3 and 6 days. Success of therapy was defined as the presence of both clinical and radiological improvement, making additional fibrinolytic doses unnecessary, and eventually leading to resolution. Secondary outcomes included the safety profile of intrapleural fibrinolytics, referral for surgery, length of hospital stay, and mortality. RESULTS: A total of 99 patients were included, of whom 51 received alteplase and 48 urokinase. Success rates for urokinase and alteplase at 3 and 6 days were not significantly different, but when only the subgroup of CPPE was considered, urokinase resulted in a high proportion of cures. There were no differences in mortality or surgical need (overall, 3 %). Five (28 %) patients receiving 20 mg of alteplase and 4 (12 %) receiving 10 mg presented serious bleeding events. CONCLUSIONS: If intrapleural fibrinolytics are intended to be used, urokinase may be more effective than alteplase in patients with non-purulent CPPE and have a lower rate of adverse events.


Asunto(s)
Empiema Pleural/tratamiento farmacológico , Fibrinolíticos/uso terapéutico , Derrame Pleural/tratamiento farmacológico , Terapia Trombolítica/métodos , Activador de Tejido Plasminógeno/uso terapéutico , Activador de Plasminógeno de Tipo Uroquinasa/uso terapéutico , Adulto , Anciano , Tubos Torácicos , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
14.
Clin Cancer Res ; 20(10): 2793-804, 2014 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-24634378

RESUMEN

PURPOSE: This study evaluated the safety, tolerability, pharmacodynamics, pharmacokinetics, and antitumor activity of ficlatuzumab, a humanized hepatocyte growth factor (HGF) inhibitory monoclonal antibody, as monotherapy in patients with advanced solid tumors and liver metastases. PATIENTS AND METHODS: Patients with p-Met (phosphorylated c-Met)-positive tumors enrolled in three dose-escalation cohorts, receiving ficlatuzumab 2, 10, or 20 mg/kg once per 14-day cycle. Pharmacodynamic changes in liver tumor biopsies and serum, pharmacokinetics, safety, and clinical activity were assessed. RESULTS: No dose-limiting toxicities occurred in the 19 patients enrolled (n = 6, 2 mg/kg; n = 7, 10 mg/kg; n = 6, 20 mg/kg). The most frequent diagnosis was colorectal cancer (n = 15; 79%). The most common treatment-emergent adverse events were asthenia, peripheral edema, hepatic pain (32% each), and cough (26%). Laboratory abnormalities of decreased serum albumin were present in all patients. Ficlatuzumab at 20 mg/kg lowered median levels of tumor p-Met (-53%), p-ERK (-43%), p-Akt (-2%), and increased median HGF levels (+33%), at the last on-study time point relative to baseline. Mean serum HGF levels increased with ficlatuzumab dose and number of treatment cycles. Ficlatuzumab exhibited linear pharmacokinetics and long terminal half-life (7.4-10 days). Best overall response was stable disease in 28% of patients, including 1 patient with pancreatic cancer with stable disease >1 year. CONCLUSIONS: Ficlatuzumab exhibited good safety/tolerability and demonstrated ability to modulate the HGF/c-Met pathway and downstream signaling in the tumor in patients with advanced solid tumors. Safety, pharmacodynamic, and pharmacokinetic data for ficlatuzumab confirmed the recommended phase II dose of 20 mg/kg once per 14-day cycle.


Asunto(s)
Anticuerpos Monoclonales/farmacocinética , Neoplasias Hepáticas/metabolismo , Neoplasias/metabolismo , Anciano , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/uso terapéutico , Área Bajo la Curva , Astenia/inducido químicamente , Tos/inducido químicamente , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Edema/inducido químicamente , Femenino , Factor de Crecimiento de Hepatocito/antagonistas & inhibidores , Factor de Crecimiento de Hepatocito/inmunología , Humanos , Hepatopatías/etiología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Dolor/inducido químicamente , Proteínas Proto-Oncogénicas c-met/metabolismo , Transducción de Señal/efectos de los fármacos , Resultado del Tratamiento
15.
Enferm Infecc Microbiol Clin ; 32(1): 37-47, 2014 Jan.
Artículo en Español | MEDLINE | ID: mdl-23642283

RESUMEN

OBJECTIVE: To develop a consensus document containing clinical recommendations for the management of human immunodeficiency virus (HIV)-associated neurocognitive disorder (HAND). METHODS: We assembled a panel of experts appointed by GeSIDA and the Secretariat of the National AIDS Plan (PNS), including internal medicine physicians with expertise in the field of HIV, neuropsychologists, neurologists and neuroradiologists. Scientific information was reviewed to October 2012 in publications and conference papers. In support of the recommendations using two levels of evidence: the strength of the recommendation in the opinion of the experts (A, B, C) and the level of empirical evidence (I, II, III), two levels based on the criteria of the Infectious Disease Society of America, already used in previous documents GeSIDA/SPNS. RESULTS: Multiple recommendations for the clinical management of these disorders are provided, including two graphics algorithms, considering both the diagnostic and possible therapeutic strategies. CONCLUSIONS: Neurocognitive disorders associated with HIV infection is currently highly prevalent, are associated with a decreased quality of life and daily activities, and given the possibility of occurrence of an increase in the coming years, there is a need to adequately manage these disorders, from a diagnostic as well as therapeutic point of view, and always from a multidisciplinary perspective.


Asunto(s)
Complejo SIDA Demencia/diagnóstico , Complejo SIDA Demencia/terapia , Algoritmos , Humanos
16.
BMC Fam Pract ; 14: 54, 2013 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-23641671

RESUMEN

BACKGROUND: Newly arrived immigrant patients who frequently use primary health care resources have difficulties in verbal communication. Also, they have a system of beliefs related to health and disease that makes difficult for health care professionals to comprehend their reasons for consultation, especially when consulting for somatic manifestations. Consequently, this is an important barrier to achieve optimum care to these groups. The current project has two main objectives: 1. To define the different stressors, the level of distress perceived, and its impact in terms of discomfort and somatisation affecting the main communities of immigrants in our area, and 2. To identify the characteristics of cross-cultural competence of primary health care professionals to best approach these reasons for consultation. METHODS/DESIGN: It will be a transversal, observational, multicentre, qualitative-quantitative study in a sample of 980 people from the five main non-European Union immigrant communities residing in Catalonia: Maghrebis, Sub-Saharans, Andean South Americans, Hindustanis, and Chinese. Sociodemographic data, level of distress, information on the different stressors and their somatic manifestations will be collected in specific questionnaires. Through a semi-structured interview and qualitative methodology, it will be studied the relation between somatic manifestations and particular beliefs of each group and how these are associated with the processes of disease and seeking for care. A qualitative methodology based on individual interviews centred on critical incidents, focal groups and in situ questionnaires will be used to study the cross-cultural competences of the professionals. DISCUSSION: It is expected a high level of chronic stress associated with the level of somatisations in the different non-European Union immigrant communities. The results will provide better knowledge of these populations and will improve the comprehension and the efficacy of the health care providers in prevention, communication, care management and management of resources.


Asunto(s)
Competencia Cultural , Trastorno Depresivo/epidemiología , Emigrantes e Inmigrantes/psicología , Conocimientos, Actitudes y Práctica en Salud , Atención Primaria de Salud/normas , Trastornos Somatomorfos/epidemiología , Estrés Psicológico/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Competencia Clínica , Comparación Transcultural , Competencia Cultural/psicología , Emigrantes e Inmigrantes/estadística & datos numéricos , Femenino , Grupos Focales , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Aceptación de la Atención de Salud/etnología , Proyectos Piloto , Investigación Cualitativa , Factores Socioeconómicos , España/epidemiología , Encuestas y Cuestionarios , Recursos Humanos , Adulto Joven
17.
Clin Cancer Res ; 18(17): 4764-74, 2012 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-22753585

RESUMEN

PURPOSE: Aurora A kinase (AAK) is a key regulator of mitosis and a target for anticancer drug development. This phase I study investigated the safety, pharmacokinetics, and pharmacodynamics of MLN8237 (alisertib), an investigational, oral, selective AAK inhibitor, in 59 adults with advanced solid tumors. EXPERIMENTAL DESIGN: Patients received MLN8237 once daily or twice daily for 7, 14, or 21 consecutive days, followed by 14 days recovery, in 21-, 28-, or 35-day cycles. Dose-limiting toxicities (DLT) and the maximum-tolerated dose (MTD) for the 7- and 21-day schedules were determined. Pharmacokinetic parameters were derived from plasma concentration-time profiles. AAK inhibition in skin and tumor biopsies was evaluated and antitumor activity assessed. RESULTS: Neutropenia and stomatitis were the most common DLTs. The MTD for the 7- and 21-day schedules was 50 mg twice daily and 50 mg once daily, respectively. MLN8237 absorption was fast (median time to maximum concentration, 2 hours). Mean terminal half-life was approximately 19 hours. At steady state, pharmacodynamic effects were shown by accumulation of mitotic and apoptotic cells in skin, and exposure-related increases in numbers of mitotic cells with characteristic spindle and chromosomal abnormalities in tumor specimens, supporting AAK inhibition by MLN8237. Stable disease was observed and was durable with repeat treatment cycles, administered over 6 months, in 6 patients, without notable cumulative toxicity. CONCLUSIONS: The recommended phase II dose of MLN8237 is 50 mg twice daily on the 7-day schedule, which is being evaluated further in a variety of malignancies, including in a phase III trial in peripheral T-cell lymphoma.


Asunto(s)
Antineoplásicos/administración & dosificación , Azepinas/administración & dosificación , Neoplasias , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Pirimidinas/administración & dosificación , Adulto , Anciano , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Aurora Quinasas , Azepinas/efectos adversos , Azepinas/farmacocinética , Biopsia , Femenino , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Neutropenia/inducido químicamente , Proteínas Serina-Treonina Quinasas/metabolismo , Pirimidinas/efectos adversos , Pirimidinas/farmacocinética , Estomatitis/inducido químicamente
18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 85(3 Pt 2): 036709, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22587211

RESUMEN

The aim of this work is the description of the chain formation phenomena observed in colloidal suspensions of superparamagnetic nanoparticles under high magnetic fields. We introduce a methodology based on an on-the-fly coarse-grain (CG) model. Within this approach, the coarse-grain objects of the simulation and their dynamic behavior are not fixed a priori at the beginning of the simulation but rather redefined on the fly. The motion of the CG objects (single particles or aggregates) is described by an anisotropic diffusion model and the magnetic dipole-dipole interaction is replaced by an effective short-range interaction between CG objects. The methodology correctly reproduces previous results from detailed Langevin dynamics simulations of dispersions of superparamagnetic colloids under strong fields while requiring an amount of CPU time orders of magnitude smaller. This substantial improvement in the computational requirements allows the simulation of problems in which the relevant phenomena extend to time scales inaccessible with previous simulation techniques. A relevant example is the waiting time dependence of the relaxation time T(2) of water protons observed in magnetic resonance experiments containing dispersions of superparamagnetic colloids, which is correctly predicted by our simulations. Future applications may include other popular real-world applications of superparamagnetic colloids such as the magnetophoretic separation processes.


Asunto(s)
Coloides/química , Campos Magnéticos , Modelos Moleculares , Difusión , Reproducibilidad de los Resultados , Factores de Tiempo
19.
Clin Cancer Res ; 17(19): 6304-12, 2011 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-21810918

RESUMEN

PURPOSE: Insulin-like growth factor-1 receptor (IGF-1R) mediates cellular processes in cancer and has been proposed as a therapeutic target. Dalotuzumab (MK-0646) is a humanized IgG1 monoclonal antibody that binds to IGF-1R preventing receptor activation. This study was designed to evaluate the safety and tolerability of dalotuzumab, determine the pharmacokinetic (PK) and pharmacodynamic (PD) profiles, and identify a recommended phase II dose. EXPERIMENTAL DESIGN: Patients with tumors expressing IGF-1R protein were allocated to dose-escalating cohorts of three or more patients each and received intravenous dalotuzumab weekly, every 2 or 3 weeks. Plasma was collected for PK analysis. Paired baseline and on-treatment skin and tumor biopsy samples were collected for PD analyses. RESULTS: Eighty patients with chemotherapy-refractory solid tumors were enrolled. One dose-limiting toxicity was noted, but a maximum-tolerated dose was not identified. Grade 1 to 3 hyperglycemia, responsive to metformin, occurred in 15 (19%) patients. At dose levels or more than 5 mg/kg, dalotuzumab mean terminal half-life was 95 hours or more, mean C(min) was more than 25 µg/mL, clearance was constant, and serum exposures were approximately dose proportional. Decreases in tumor IGF-1R, downstream receptor signaling, and Ki67 expression were observed. (18)F-Fluorodeoxy-glucose positron emission tomography metabolic responses occurred in three patients. One patient with Ewing's sarcoma showed a mixed radiologic response. The recommended phase II doses were 10, 20, and 30 mg/kg for the weekly, every other week, and every third week schedules, respectively. CONCLUSIONS: Dalotuzumab was generally well-tolerated, exhibited dose-proportional PK, inhibited IGF-1R pathway signaling and cell proliferation in treated tumors, and showed clinical activity. The low clearance rate and long terminal half-life support more extended dosing intervals.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales/uso terapéutico , Receptor IGF Tipo 1/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/farmacocinética , Antineoplásicos/uso terapéutico , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico
20.
Cancer Res ; 71(3): 675-85, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21148750

RESUMEN

The mitotic kinase Aurora A is an important therapeutic target for cancer therapy. This study evaluated new mechanism-based pharmacodynamic biomarkers in cancer patients in two phase I studies of MLN8054, a small-molecule inhibitor of Aurora A kinase. Patients with advanced solid tumors received MLN8054 orally for 7 consecutive days in escalating dose cohorts, with skin and tumor biopsies obtained before and after dosing. Skin biopsies were evaluated for increased mitotic cells within the basal epithelium. Tumor biopsies were assessed for accumulation of mitotic cells within proliferative tumor regions. Several patients in the highest dose cohorts showed marked increases in the skin mitotic index after dosing. Although some tumors exhibited increases in mitotic cells after dosing, others displayed decreases, a variable outcome consistent with dual mechanisms of mitotic arrest and mitotic slippage induced by antimitotics in tumors. To provide a clearer picture, mitotic cell chromosome alignment and spindle bipolarity, new biomarkers of Aurora A inhibition that act independently of mitotic arrest or slippage, were assessed in the tumor biopsies. Several patients, primarily in the highest dose cohorts, had marked decreases in the percentage of mitotic cells with aligned chromosomes and bipolar spindles after dosing. Evidence existed for an exposure-effect relationship for mitotic cells with defects in chromosome alignment and spindle bipolarity that indicated a biologically active dose range. Outcomes of pharmacodynamic assays from skin and tumor biopsies were concordant in several patients. Together, these new pharmacodynamic assays provide evidence for Aurora A inhibition by MLN8054 in patient skin and tumor tissues.


Asunto(s)
Benzazepinas/farmacología , Benzazepinas/farmacocinética , Biomarcadores de Tumor/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Aurora Quinasas , Benzazepinas/efectos adversos , Benzazepinas/sangre , Biomarcadores de Tumor/sangre , Biopsia , Relación Dosis-Respuesta a Droga , Humanos , Mitosis/efectos de los fármacos , Neoplasias/sangre , Neoplasias/patología , Piel/metabolismo , Piel/patología
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