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1.
J Alzheimers Dis ; 97(1): 359-372, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38073386

RESUMEN

BACKGROUND: Patients with Alzheimer's disease (AD) demonstrate progressive white matter atrophy and myelin loss. Restoring myelin content or preventing demyelination has been suggested as a therapeutic approach for AD. OBJECTIVE: Herein, we investigate the effects of non-invasive, combined visual and auditory gamma-sensory stimulation on white matter atrophy and myelin content loss in patients with AD. METHODS: In this study, we used the magnetic resonance imaging (MRI) data from the OVERTURE study (NCT03556280), a randomized, controlled, clinical trial in which active treatment participants received daily, non-invasive, combined visual and auditory, 40 Hz stimulation for six months. A subset of OVERTURE participants who meet the inclusion criteria for detailed white matter (N = 38) and myelin content (N = 36) assessments are included in the analysis. White matter volume assessments were performed using T1-weighted MRI, and myelin content assessments were performed using T1-weighted/T2-weighted MRI. Treatment effects on white matter atrophy and myelin content loss were assessed. RESULTS: Combined visual and auditory gamma-sensory stimulation treatment is associated with reduced total and regional white matter atrophy and myelin content loss in active treatment participants compared to sham treatment participants. Across white matter structures evaluated, the most significant changes were observed in the entorhinal region. CONCLUSIONS: The study results suggest that combined visual and auditory gamma-sensory stimulation may modulate neuronal network function in AD in part by reducing white matter atrophy and myelin content loss. Furthermore, the entorhinal region MRI outcomes may have significant implications for early disease intervention, considering the crucial afferent connections to the hippocampus and entorhinal cortex.


Asunto(s)
Enfermedad de Alzheimer , Sustancia Blanca , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/terapia , Enfermedad de Alzheimer/patología , Sustancia Blanca/patología , Vaina de Mielina/patología , Imagen por Resonancia Magnética , Atrofia/patología
2.
Nat Commun ; 14(1): 1900, 2023 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-37019892

RESUMEN

Blood-brain barrier disruption marks the onset of cerebral adrenoleukodystrophy (CALD), a devastating cerebral demyelinating disease caused by loss of ABCD1 gene function. The underlying mechanism are not well understood, but evidence suggests that microvascular dysfunction is involved. We analyzed cerebral perfusion imaging in boys with CALD treated with autologous hematopoietic stem-cells transduced with the Lenti-D lentiviral vector that contains ABCD1 cDNA as part of a single group, open-label phase 2-3 safety and efficacy study (NCT01896102) and patients treated with allogeneic hematopoietic stem cell transplantation. We found widespread and sustained normalization of white matter permeability and microvascular flow. We demonstrate that ABCD1 functional bone marrow-derived cells can engraft in the cerebral vascular and perivascular space. Inverse correlation between gene dosage and lesion growth suggests that corrected cells contribute long-term to remodeling of brain microvascular function. Further studies are needed to explore the longevity of these effects.


Asunto(s)
Adrenoleucodistrofia , Trasplante de Células Madre Hematopoyéticas , Sustancia Blanca , Masculino , Humanos , Adrenoleucodistrofia/genética , Sustancia Blanca/patología , Células Madre Hematopoyéticas/patología , Terapia Genética , Trasplante de Células Madre Hematopoyéticas/métodos
3.
Phys Chem Chem Phys ; 24(29): 17744-17750, 2022 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-35843214

RESUMEN

The 2D self-assemblies and structural transitions of pentacene on a Cd(0001) surface have been investigated with low temperature scanning tunneling microscopy (STM). With increasing coverage, pentacene molecules show a structural evolution from the initial disordered gas-like phase through the porous network phase to the herringbone phase, and finally to the brickwall phase at the full monolayer. In particular, orientational frustration and cooperative rotation of pentacene molecules take place in the herringbone phase. Furthermore, successive STM scanning leads to structural interconversions between the porous network phase, herringbone phase, and brickwall phase, indicating the metastability of the 2D assembled structures of pentacene on Cd(0001). These structural transitions and interconversion can be attributed to the interplay between the repulsive electrostatic forces resulting from the charge transfer from the substrate to pentacene and the attractive effects originating from dipole-dipole interactions and intermolecular van der Waals forces.

4.
Phys Chem Chem Phys ; 24(17): 10292-10296, 2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35437551

RESUMEN

Chiral resolution is of fundamental importance to conglomerate or racemate crystallization. Here we demonstrate that the spontaneous chiral resolution of pentahelicene racemates occurred in the monolayer domains. When deposited on a Cd(0001) surface, pentahelicene molecules crystallize into a commensurate (6 × 6)R0° structure built mainly from homochiral trimers. Spontaneous chirality separation takes place in the form of opposite mirror domains, where 2D enantiomorphism is not expressed by the oblique adlattice, but by the supramolecular chirality of the pentahelicene trimers. Furthermore, annealing the sample or extreme close-packing lead to the presence of lattice handedness through the formation of a porous network structure or an edge-on phase. These results provide valuable insight for 2D conglomerate crystallization and stereochemical recognition.

5.
Anat Rec (Hoboken) ; 304(11): 2566-2578, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34636498

RESUMEN

COVID-19 (coronavirus) has spread all over the world with a high infection rate. Currently, there are no targeted therapeutic drugs for COVID-19 as well as for stress induced by COVID-19. The unpredictable events of COVID-19 can trigger feelings of fear, worry, or unease in people, leading to stress-related disorders such as depression and anxiety. It has been reported that individuals, including COVID-19 patients, medical staff, and ordinary people, are under both physical and psychological pressure, and many of them have developed depression or anxiety during this pandemic. Traditional Chinese medicine (TCM) has been widely used in treating depression with relatively better safety and efficacy and may have an important role in treating stress-related disorders induced by COVID-19. In this review, we collected the common TCM treatment methods including Qigong, Acupuncture, Five Elements Musical Therapy, Five Elements Emotional Therapy, and Chinese herbal medicine from the databases of PubMed and the China National Knowledge Internet to illustrate the effect of TCM on depression. The better knowledge of TCM and implementation of TCM in COVID-19 clinics may help to effectively improve depression induced by COVID-19, may assist people to maintain a healthy physical and mental quality, and may alleviate the current shortage of medical resources.


Asunto(s)
COVID-19/epidemiología , COVID-19/terapia , Depresión/epidemiología , Depresión/terapia , Medicina Tradicional China/métodos , Terapia por Acupuntura/métodos , Medicamentos Herbarios Chinos/uso terapéutico , Humanos , Qigong/métodos , Resultado del Tratamiento
6.
Curr Protoc ; 1(4): e99, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33826806

RESUMEN

Genetically encoded peptide-protein coupling reactions, such as the SpyTag/SpyCatcher chemistry, are recent additions to the expanding toolbox of protein bioconjugation. The alternative three-component ligation system, e.g., SpyStapler-mediated SpyTag/BDTag coupling, retains most advantages of the Tag/Catcher chemistry, yet requires only two short peptide tags in the genetic fusion for side-chain ligation. Not only does this facilitate the construction of large protein conjugates directly from as-expressed protein components with minimal disruption to their function, but it also provides an entirely new mode of bioconjugation via mechanical bonding, which could impart additional functional benefits such as improved activity and enhanced stability to the conjugate. Such features are attractive for improving the pharmacokinetic performance of protein therapeutics. Herein we describe protocols for SpyStapler-mediated SpyTag/BDTag coupling for protein bioconjugation. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Conjugation via isopeptide bond Support Protocol: Purification by size-exclusion chromatography Basic Protocol 2: Conjugation via mechanical bond.


Asunto(s)
Péptidos , Proteínas , Fenómenos Físicos
7.
RSC Adv ; 11(23): 14148-14153, 2021 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35423925

RESUMEN

The interfacial structures of C60 molecules adsorbed on solid surfaces are essential for a wide range of scientific and technological processes in carbon-based nanodevices. Here, we report structural transitions of the C60 monolayer on the Bi(111) surface studied via low-temperature scanning tunneling microscopy (STM). With an increase in temperature, the structure of the C60 monolayer transforms from local-order structures to a (√93 × âˆš93) R20° superstructure, and then to a (11 × 11) R0° superstructure. Moreover, the individual C60 molecules in different superstructures have different orientations. C60 molecules adopt the 6 : 6 C-C bond and 5 : 6 C-C bond facing-up, mixed orientations, and hexagon facing-up in the local-order structure, (√93 × âˆš93) R20°, and (11 × 11) R0° superstructure, respectively. These results shed important light on the growth mechanism of C60 molecules on solid surfaces.

8.
Bioresour Bioprocess ; 8(1): 124, 2021 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38650281

RESUMEN

BACKGROUND: In the last decades, replicating expression vectors based on plant geminivirus have been widely used for enhancing the efficiency of plant transient expression. By using the replicating expression vector derived from bean yellow dwarf virus and green fluorescent protein as a reporter, we investigated the effects of α-naphthalene acetic acid, gibberellins3, and 6-benzyladenine, as three common plant growth regulators, on the plant biomass and efficiency of transient expression during the process of transient expression in Nicotiana benthamiana L. leaves. RESULTS: With the increase of the concentration of α-naphthalene acetic acid, gibberellins3, and 6-benzyladenine (from 0.1 to 1.6 mg/L), the fresh weight, dry weight, and leaf area of the seedlings increased first and then returned to the levels similar to the controls (without chemical treatment). The treatment with α-naphthalene acetic acid at 0.2 and 0.4 mg/L can enhance the level of transient expression of green fluorescent protein, which peaked at 0.4 mg/L α-naphthalene acetic acid and was increased about by 19%, compared to the controls. Gibberellins3 at 0.1-0.4 mg/L can enhance the level of transient expression of green fluorescent protein, which peaked at 0.2 mg/L gibberellins3 and was increased by 25%. However, the application of 6-benzyladenine led to decrease in the level of transient expression of green fluorescent protein. CONCLUSIONS: The appropriate plant growth regulators at moderate concentration could be beneficial to the expression of foreign genes from the Agrobacterium-mediated transient expression system in plants. Thus, appropriate plant growth regulators could be considered as exogenous components that are applied for the production of recombinant protein by plant-based transient expression systems.

9.
Biochemistry ; 59(24): 2226-2236, 2020 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-32469203

RESUMEN

The interplay between protein folding and chemical reaction has been an intriguing subject. In this contribution, we report the study of SpyTag and SpyCatcher reactive mutants using a combination of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, liquid chromatography and mass spectrometry, circular dichroism, and NMR spectroscopy. It was found that the wild-type SpyCatcher is well-folded in solution and docks with SpyTag to form an intermediate that promotes isopeptide bond formation. By contrast, the double mutant SpyCatcherVA is disordered in solution yet remains reactive toward SpyTag, forming a well-folded covalent complex. Control experiments using the catalytically inactive mutants further reveal the critical role of the isopeptide bond in stabilizing the otherwise loose SpyTag-SpyCatcherVA complex, amplifying the effect of the minute sequence disparity. We believe that the synergy between protein folding and isopeptide bonding is an effective way to enhance protein stability and engineer protein-protein interactions.


Asunto(s)
Mutación , Péptidos/química , Péptidos/genética , Dicroismo Circular , Ciclización , Resonancia Magnética Nuclear Biomolecular , Estabilidad Proteica
10.
Anat Rec (Hoboken) ; 303(8): 2154-2167, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32353209

RESUMEN

A syndrome (Zheng in Chinese) plays a critical role in disease identification, diagnosis, and treatment in traditional Chinese medicine (TCM). Clinically, the liver Qi stagnation and spleen deficiency syndrome (LQSSDS) is one of the most common syndrome patterns. Over the past few decades, several animal models have been developed to understand the potential mechanisms of LQSSDS, but until now, simulation of the syndrome is still unclear. Recently, several studies have confirmed that an animal model combining a disease and a syndrome is appropriate for simulating TCM syndromes. Overlapping previous studies have reported that depression is highly associated with LQSSDS; hence, we attempted to develop a rat model combining depression and LQSSDS. We exposed the rats to different durations of chronic unpredictable mild stress (CUMS). Subsequently, the evaluation indicators at macrolevel consisted of behavioral tests including open field test, sucrose preference test, and forced swim test, food intake, body weight, white adipose tissue, fecal water content, visceral hypersensitivity, and small bowel transit, and the evaluation indicators at microlevel included changes of hypothalamic-pituitary-adrenal axis. Serum D-xylose absorption was used to comprehensively confirm and assess whether the model was successful during the CUMS-induced process. The results showed that rats exposed to 6-week CUMS procedure exhibited significantly similar traits to the phenotypes of LQSSDS and depression. This study provided a new rat model for the LQSSDS and could potentially lead to a better understanding of the pathophysiology of LQSSDS and the development of new drugs for this syndrome.


Asunto(s)
Depresión/fisiopatología , Modelos Animales de Enfermedad , Hígado/fisiopatología , Medicina Tradicional China , Bazo/fisiopatología , Animales , Sistema Hipotálamo-Hipofisario/fisiopatología , Masculino , Sistema Hipófiso-Suprarrenal/fisiopatología , Qi , Ratas , Ratas Transgénicas
11.
Angew Chem Int Ed Engl ; 58(32): 11097-11104, 2019 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-31218786

RESUMEN

Covalent-bond-forming protein domains can be versatile tools for creating unconventional protein topologies. In this study, through rewiring the SpyTag-SpyCatcher complex to induce rationally designed chain entanglement, we developed a biologically enabled active template for the concise, modular, and programmable synthesis of protein heterocatenanes both in vitro and in vivo. It is a general and good-yielding reaction for forming heterocatenanes with precisely controlled ring sizes and broad structural diversity. More importantly, such heterocatenation not only provides an efficient means of bioconjugation for integrating multiple native functions, but also enhances the stability of the component proteins against proteolytic digestion, thermal unfolding, and freeze/thaw-induced mechanical denaturation, thus opening up a versatile path in the nascent field of protein-topology engineering.

13.
Front Comput Neurosci ; 13: 81, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31920606

RESUMEN

Glioblastoma, the most frequent primary malignant brain neoplasm, is genetically diverse and classified into four transcriptomic subtypes, i. e., classical, mesenchymal, proneural, and neural. Currently, detection of transcriptomic subtype is based on ex vivo analysis of tissue that does not capture the spatial tumor heterogeneity. In view of accumulative evidence of in vivo imaging signatures summarizing molecular features of cancer, this study seeks robust non-invasive radiographic markers of transcriptomic classification of glioblastoma, based solely on routine clinically-acquired imaging sequences. A pre-operative retrospective cohort of 112 pathology-proven de novo glioblastoma patients, having multi-parametric MRI (T1, T1-Gd, T2, T2-FLAIR), collected from the Hospital of the University of Pennsylvania were included. Following tumor segmentation into distinct radiographic sub-regions, diverse imaging features were extracted and support vector machines were employed to multivariately integrate these features and derive an imaging signature of transcriptomic subtype. Extracted features included intensity distributions, volume, morphology, statistics, tumors' anatomical location, and texture descriptors for each tumor sub-region. The derived signature was evaluated against the transcriptomic subtype of surgically-resected tissue specimens, using a 5-fold cross-validation method and a receiver-operating-characteristics analysis. The proposed model was 71% accurate in distinguishing among the four transcriptomic subtypes. The accuracy (sensitivity/specificity) for distinguishing each subtype (classical, mesenchymal, proneural, neural) from the rest was equal to 88.4% (71.4/92.3), 75.9% (83.9/72.8), 82.1% (73.1/84.9), and 75.9% (79.4/74.4), respectively. The findings were also replicated in The Cancer Genomic Atlas glioblastoma dataset. The obtained imaging signature for the classical subtype was dominated by associations with features related to edge sharpness, whereas for the mesenchymal subtype had more pronounced presence of higher T2 and T2-FLAIR signal in edema, and higher volume of enhancing tumor and edema. The proneural and neural subtypes were characterized by the lower T1-Gd signal in enhancing tumor and higher T2-FLAIR signal in edema, respectively. Our results indicate that quantitative multivariate analysis of features extracted from clinically-acquired MRI may provide a radiographic biomarker of the transcriptomic profile of glioblastoma. Importantly our findings can be influential in surgical decision-making, treatment planning, and assessment of inoperable tumors.

14.
Sci Rep ; 8(1): 17062, 2018 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-30459364

RESUMEN

Functional MRI may identify critical windows of opportunity for drug delivery and distinguish between early treatment responders and non-responders. Using diffusion-weighted, dynamic contrast-enhanced, and dynamic susceptibility contrast MRI, as well as pro-angiogenic and pro-inflammatory blood markers, we prospectively studied the physiologic tumor-related changes in fourteen newly diagnosed glioblastoma patients during standard therapy. 153 MRI scans and blood collection were performed before chemoradiation (baseline), weekly during chemoradiation (week 1-6), monthly before each cycle of adjuvant temozolomide (pre-C1-C6), and after cycle 6. The apparent diffusion coefficient, volume transfer coefficient (Ktrans), and relative cerebral blood volume (rCBV) and flow (rCBF) were calculated within the tumor and edema regions and compared to baseline. Cox regression analysis was used to assess the effect of clinical variables, imaging, and blood markers on progression-free (PFS) and overall survival (OS). After controlling for additional covariates, high baseline rCBV and rCBF within the edema region were associated with worse PFS (microvessel rCBF: HR = 7.849, p = 0.044; panvessel rCBV: HR = 3.763, p = 0.032; panvessel rCBF: HR = 3.984; p = 0.049). The same applied to high week 5 and pre-C1 Ktrans within the tumor region (week 5 Ktrans: HR = 1.038, p = 0.003; pre-C1 Ktrans: HR = 1.029, p = 0.004). Elevated week 6 VEGF levels were associated with worse OS (HR = 1.034; p = 0.004). Our findings suggest a role for rCBV and rCBF at baseline and Ktrans and VEGF levels during treatment as markers of response. Functional imaging changes can differ substantially between tumor and edema regions, highlighting the variable biologic and vascular state of tumor microenvironment during therapy.


Asunto(s)
Biomarcadores/análisis , Quimioradioterapia/mortalidad , Imagen de Difusión por Resonancia Magnética/métodos , Glioblastoma/patología , Temozolomida/uso terapéutico , Microambiente Tumoral , Adulto , Anciano , Antineoplásicos Alquilantes/uso terapéutico , Volumen Sanguíneo Cerebral , Quimioterapia Adyuvante , Medios de Contraste , Femenino , Estudios de Seguimiento , Glioblastoma/sangre , Glioblastoma/terapia , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Tasa de Supervivencia
15.
Biomacromolecules ; 19(3): 1065-1073, 2018 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-29443516

RESUMEN

Protein-based materials call for innovative processing techniques to integrate their unique biologically enabled functions with other materials of complementary features. Herein, we report the covalent protein layer-by-layer assembly via orthogonal "Tag-Catcher" reactions as a facile and robust approach to make entirely protein-based multilayers on a variety of substrates. Programmed assembly of native telechelic proteins not only endows the materials valuable stimuli-sensitive behaviors, but also unique properties unparalleled by any synthetic counterparts. As proof of concept, super uranyl-binding protein (SUP) is immobilized on silica gel by this method with tunable capacity and enhanced capability for uranyl sequestration. Not only is the capturing performance enhanced in the multilayer setup, it also confers resilience to recycling, allowing efficient harvest of uranyl with an average of ∼90% and ∼60% recovery rate in over 10 cycles from water and synthetic seawater, respectively. The approach is the first entirely protein-based multilayers covalently assembled by the layer-by-layer method. It provides a platform for immobilizing proteins with synergistic enhancement of function and resilience and expands the scope and capability of genetically encoded protein-based materials.


Asunto(s)
Proteínas Portadoras/química , Escherichia coli/química , Uranio/química , Uranio/aislamiento & purificación , Proteínas Portadoras/biosíntesis , Proteínas Portadoras/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
16.
Neuroinformatics ; 16(3-4): 431-444, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29353341

RESUMEN

Multi-site brain MRI analysis is needed in big data neuroimaging studies, but challenging. The challenges lie in almost every analysis step including skull stripping. The diversities in multi-site brain MR images make it difficult to tune parameters specific to subjects or imaging protocols. Alternatively, using constant parameter settings often leads to inaccurate, inconsistent and even failed skull stripping results. One reason is that images scanned at different sites, under different scanners or protocols, and/or by different technicians often have very different fields of view (FOVs). Normalizing FOV is currently done manually or using ad hoc pre-processing steps, which do not always generalize well to multi-site diverse images. In this paper, we show that (a) a generic FOV normalization approach is possible in multi-site diverse images; we show experiments on images acquired from Philips, GE, Siemens scanners, from 1.0T, 1.5T, 3.0T field of strengths, and from subjects 0-90 years of ages; and (b) generic FOV normalization improves skull stripping accuracy and consistency for multiple skull stripping algorithms; we show this effect for 5 skull stripping algorithms including FSL's BET, AFNI's 3dSkullStrip, FreeSurfer's HWA, BrainSuite's BSE, and MASS. We have released our FOV normalization software at http://www.nitrc.org/projects/normalizefov .


Asunto(s)
Encéfalo/diagnóstico por imagen , Bases de Datos Factuales , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Niño , Preescolar , Bases de Datos Factuales/estadística & datos numéricos , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , Cráneo/diagnóstico por imagen , Adulto Joven
17.
Brain ; 140(12): 3139-3152, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-29136088

RESUMEN

Cerebral X-linked adrenoleukodystrophy is a devastating neurodegenerative disorder caused by mutations in the ABCD1 gene, which lead to a rapidly progressive cerebral inflammatory demyelination in up to 60% of affected males. Selective brain endothelial dysfunction and increased permeability of the blood-brain barrier suggest that white matter microvascular dysfunction contributes to the conversion to cerebral disease. Applying a vascular model to conventional dynamic susceptibility contrast magnetic resonance perfusion imaging, we demonstrate that lack of ABCD1 function causes increased capillary flow heterogeneity in asymptomatic hemizygotes predominantly in the white matter regions and developmental stages with the highest probability for conversion to cerebral disease. In subjects with ongoing inflammatory demyelination we observed a sequence of increased capillary flow heterogeneity followed by blood-brain barrier permeability changes in the perilesional white matter, which predicts lesion progression. These white matter microvascular alterations normalize within 1 year after treatment with haematopoietic stem cell transplantation. For the first time in vivo, our studies unveil a model to assess how ABCD1 alters white matter microvascular function and explores its potential as an earlier biomarker for monitoring disease progression and response to treatment.


Asunto(s)
Miembro 1 de la Subfamilia D de Transportador de Casetes de Unión al ATP/genética , Adrenoleucodistrofia/diagnóstico por imagen , Microcirculación , Sustancia Blanca/irrigación sanguínea , Adolescente , Adrenoleucodistrofia/genética , Adrenoleucodistrofia/terapia , Enfermedades Asintomáticas , Barrera Hematoencefálica/metabolismo , Estudios de Casos y Controles , Circulación Cerebrovascular , Niño , Preescolar , Trasplante de Células Madre Hematopoyéticas , Hemicigoto , Humanos , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética , Masculino , Mutación , Permeabilidad , Sustancia Blanca/diagnóstico por imagen , Adulto Joven
18.
J Neurooncol ; 131(3): 603-610, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27853960

RESUMEN

Targeting tumor angiogenesis is a potential therapeutic strategy for glioblastoma because of its high vascularization. Tivozanib is an oral pan-VEGF receptor tyrosine kinase inhibitor that hits a central pathway in glioblastoma angiogenesis. We conducted a phase II study to test the effectiveness of tivozanib in patients with recurrent glioblastoma. Ten adult patients were enrolled and treated with tivozanib 1.5 mg daily, 3 weeks on/1 week off in 28-day cycles. Brain MRI and blood biomarkers of angiogenesis were performed at baseline, within 24-72 h of treatment initiation, and monthly thereafter. Dynamic contrast enhanced MRI, dynamic susceptibility contrast MRI, and vessel architecture imaging were used to assess vascular effects. Resting state MRI was used to assess brain connectivity. Best RANO criteria responses were: 1 complete response, 1 partial response, 4 stable diseases, and 4 progressive disease (PD). Two patients were taken off study for toxicity and 8 patients were taken off study for PD. Median progression-free survival was 2.3 months and median overall survival was 8.1 months. Baseline abnormal tumor vascular permeability, blood flow, tissue oxygenation and plasma sVEGFR2 significantly decreased and plasma PlGF and VEGF increased after treatment, suggesting an anti-angiogenic effect of tivozanib. However, there were no clear structural changes in vasculature as vessel caliber and enhancing tumor volume did not significantly change. Despite functional changes in tumor vasculature, tivozanib had limited anti-tumor activity, highlighting the limitations of anti-VEGF monotherapy. Future studies in glioblastoma should leverage the anti-vascular activity of agents targeting VEGF to enhance the activity of other therapies.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Compuestos de Fenilurea/uso terapéutico , Quinolinas/uso terapéutico , Receptores de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Administración Oral , Anciano , Biomarcadores de Tumor/sangre , Neoplasias Encefálicas/sangre , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Femenino , Glioblastoma/sangre , Glioblastoma/diagnóstico por imagen , Glioblastoma/patología , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/patología , Neovascularización Patológica/tratamiento farmacológico , Receptores de Factores de Crecimiento Endotelial Vascular/sangre , Análisis de Supervivencia , Resultado del Tratamiento
19.
Neuroimage Clin ; 12: 34-40, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27358767

RESUMEN

BACKGROUND AND PURPOSE: In treating glioblastoma (GB), surgical and chemotherapeutic treatment guidelines are, for the most part, independent of tumor location. In this work, we compiled imaging data from a large cohort of GB patients to create statistical atlases illustrating the disease spatial frequency as a function of patient demographics as well as tumor characteristics. MATERIALS AND METHODS: Two-hundred-six patients with pathology-proven glioblastoma were included. Of those, 65 had pathology-proven recurrence and 113 had molecular subtype and genetic information. We used validated software to segment the tumors in all patients and map them from patient space into a common template. We then created statistical maps that described the spatial location of tumors with respect to demographics and tumor characteristics. We applied a chi-square test to determine whether pattern differences were statistically significant. RESULTS: The most frequent location for glioblastoma in our patient population is the right temporal lobe. There are statistically significant differences when comparing patterns using demographic data such as gender (p = 0.0006) and age (p = 0.006). Small and large tumors tend to occur in separate locations (p = 0.0007). The tumors tend to occur in different locations according to their molecular subtypes (p < 10(- 6)). The classical subtype tends to spare the frontal lobes, the neural subtype tend to involve the inferior right frontal lobe. Although the sample size is limited, there was a difference in location according to EGFR VIII genotype (p < 10(- 4)), with a right temporal dominance for EFGR VIII negative tumors, and frontal lobe dominance in EGFR VIII positive tumors. CONCLUSIONS: Spatial location of GB is an important factor that correlates with demographic factors and tumor characteristics, which should therefore be considered when evaluating a patient with GB and might assist in personalized treatment.


Asunto(s)
Neoplasias Encefálicas/patología , Glioblastoma/patología , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Atlas como Asunto , Neoplasias Encefálicas/diagnóstico por imagen , Femenino , Glioblastoma/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
20.
Neurosurgery ; 78(4): 572-80, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26813856

RESUMEN

BACKGROUND: Glioblastoma is an aggressive and highly infiltrative brain cancer. Standard surgical resection is guided by enhancement on postcontrast T1-weighted (T1) magnetic resonance imaging, which is insufficient for delineating surrounding infiltrating tumor. OBJECTIVE: To develop imaging biomarkers that delineate areas of tumor infiltration and predict early recurrence in peritumoral tissue. Such markers would enable intensive, yet targeted, surgery and radiotherapy, thereby potentially delaying recurrence and prolonging survival. METHODS: Preoperative multiparametric magnetic resonance images (T1, T1-gadolinium, T2-weighted, T2-weighted fluid-attenuated inversion recovery, diffusion tensor imaging, and dynamic susceptibility contrast-enhanced magnetic resonance images) from 31 patients were combined using machine learning methods, thereby creating predictive spatial maps of infiltrated peritumoral tissue. Cross-validation was used in the retrospective cohort to achieve generalizable biomarkers. Subsequently, the imaging signatures learned from the retrospective study were used in a replication cohort of 34 new patients. Spatial maps representing the likelihood of tumor infiltration and future early recurrence were compared with regions of recurrence on postresection follow-up studies with pathology confirmation. RESULTS: This technique produced predictions of early recurrence with a mean area under the curve of 0.84, sensitivity of 91%, specificity of 93%, and odds ratio estimates of 9.29 (99% confidence interval: 8.95-9.65) for tissue predicted to be heavily infiltrated in the replication study. Regions of tumor recurrence were found to have subtle, yet fairly distinctive multiparametric imaging signatures when analyzed quantitatively by pattern analysis and machine learning. CONCLUSION: Visually imperceptible imaging patterns discovered via multiparametric pattern analysis methods were found to estimate the extent of infiltration and location of future tumor recurrence, paving the way for improved targeted treatment.


Asunto(s)
Neoplasias Encefálicas/patología , Glioblastoma/patología , Adulto , Anciano , Área Bajo la Curva , Neoplasias Encefálicas/cirugía , Estudios de Cohortes , Imagen de Difusión Tensora , Femenino , Glioblastoma/cirugía , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Neuroimagen , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Estudios Retrospectivos
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