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1.
Childs Nerv Syst ; 37(4): 1143-1150, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33185713

RESUMO

PURPOSE: Determine the feasibility and utility of using a battery of tests utilized, so far, to assess neurological-cognitive functions in the typical adult population and identify the spectrum of these functions in adult SBM patients. METHODS: Prospective study in which 15 participants (mean age = 28.7 ± 8.7 years, range = 19-45 years) completed the targeted battery of tests (n = 5-15/test) previously standardized to the general population. Results were compared with normative data. RESULTS: Statistically significant differences with normative means were noted in the following tests: Montreal Cognitive Assessment (MoCA), Functional Activities Questionnaire (FAQ), and NIH Toolbox Fine Motor (Dexterity and Grip Strength) tests. Cohort means for NIH Toolbox Fluid, Crystallized, and Cognitive Composite Scores and Timed Up and GO (TUG) were not different from normative means. CONCLUSION: All tests were successfully completed by cohort. Whereas many aspects of cognition were normal, tests assessing visual-constructural, calculation, motor, and fluency functions did show differences from population means. Numerous tests assessing multiple domains are needed and can be used in future aging studies to appreciate the spectrum of cognitive and motor abilities in adults with SBM.


Assuntos
Meningomielocele , Disrafismo Espinal , Adulto , Cognição , Humanos , Meningomielocele/complicações , Pessoa de Meia-Idade , Testes Neuropsicológicos , Projetos Piloto , Estudos Prospectivos , Adulto Jovem
2.
Opt Express ; 27(26): 38435-38450, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31878611

RESUMO

In conventional laser-scanning microscopy, images are formed by acquiring the signal from pixel to pixel. Here, we report more than one order of magnitude reduction in acquisition time of Interferometric Second Harmonic Generation (I-SHG) by scanning the phase within each pixel, to characterize the relative polarity of various samples. Using an electro-optic phase-scanner, we show that the phase-shift patterns required for interferometry can be applied at each pixel during the scanning of the sample, allowing single-scan I-SHG (1S-ISHG) measurements. Requiring exposure times comparable to standard SHG intensity images, the additional phase information of the signal can thus be retrieved in parallel to its amplitude at the time-scale of seconds. Moreover, slower modulations can be used to enhance the precision of the phase measurement, without any spatial or temporal shift between interferograms, in contrast to conventional frame phase-shifting I-SHG (standard I-SHG). This continues to extend I-SHG to dynamical processes, and opens it to large-scale studies, as well as to imaging samples where the signal-to-noise ratio is an issue.

3.
Biochem Biophys Res Commun ; 436(3): 543-50, 2013 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-23770369

RESUMO

Vascular endothelial growth factor-A (VEGF-A) plays a critical role in physiologic and pathologic angiogenesis through its receptors especially through VEGFR2. The lack of cross-reactivity of monoclonal antibodies with human VEGFR2/mouse Flk-1 is a major obstacle in preclinical developments. In this study, using a unique hybridoma technique, we generated a panel of 30 neutralization anti-VEGFR2 rabbit monoclonal antibodies (RabMAbs) either blocking VEGF/VEGFR2 interaction or inhibiting VEGF-stimulated VEGFR2 tyrosine kinase phosphorylation. Among 18 RabMAbs with human/mouse VEGFR2 cross-reactivity, we humanized one lead candidate RabMAb by Mutational Lineage Guided (MLG) method and further demonstrated its potent inhibition of tumor growth in xenograft mouse model. Our study suggests that RabMAbs are highly relevant for therapeutic applications.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Neutralizantes/farmacologia , Afinidade de Anticorpos , Especificidade de Anticorpos , Antineoplásicos/administração & dosagem , Reações Cruzadas , Feminino , Células HEK293 , Humanos , Hibridomas/imunologia , Concentração Inibidora 50 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Dados de Sequência Molecular , Neovascularização Patológica/imunologia , Neovascularização Patológica/terapia , Fosforilação , Ligação Proteica , Mapeamento de Interação de Proteínas , Coelhos , Fator A de Crescimento do Endotélio Vascular/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Digit Biomark ; 4(Suppl 1): 59-72, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33442581

RESUMO

BACKGROUND: Fatigue is a broad, multifactorial concept encompassing feelings of reduced physical and mental energy levels. Fatigue strongly impacts patient health-related quality of life across a huge range of conditions, yet, to date, tools available to understand fatigue are severely limited. METHODS: After using a recurrent neural network-based algorithm to impute missing time series data form a multisensor wearable device, we compared supervised and unsupervised machine learning approaches to gain insights on the relationship between self-reported non-pathological fatigue and multimodal sensor data. RESULTS: A total of 27 healthy subjects and 405 recording days were analyzed. Recorded data included continuous multimodal wearable sensor time series on physical activity, vital signs, and other physiological parameters, and daily questionnaires on fatigue. The best results were obtained when using the causal convolutional neural network model for unsupervised representation learning of multivariate sensor data, and random forest as a classifier trained on subject-reported physical fatigue labels (weighted precision of 0.70 ± 0.03 and recall of 0.73 ± 0.03). When using manually engineered features on sensor data to train our random forest (weighted precision of 0.70 ± 0.05 and recall of 0.72 ± 0.01), both physical activity (energy expenditure, activity counts, and steps) and vital signs (heart rate, heart rate variability, and respiratory rate) were important parameters to measure. Furthermore, vital signs contributed the most as top features for predicting mental fatigue compared to physical ones. These results support the idea that fatigue is a highly multimodal concept. Analysis of clusters from sensor data highlighted a digital phenotype indicating the presence of fatigue (95% of observations) characterized by a high intensity of physical activity. Mental fatigue followed similar trends but was less predictable. Potential future directions could focus on anomaly detection assuming longer individual monitoring periods. CONCLUSION: Taken together, these results are the first demonstration that multimodal digital data can be used to inform, quantify, and augment subjectively captured non-pathological fatigue measures.

5.
Assay Drug Dev Technol ; 11(5): 326-32, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23772553

RESUMO

We present here a label-free microarray-based assay platform that we used to identify inhibitors of vascular endothelial growth factor (VEGF)-kinase-insertion domain receptor (KDR) binding. Supported by a combination of special ellipsometry-based optical detection and small molecule microarrays (SMM), this platform consists of three assays: (1) the first assay detects binding of a target protein with SMM and identifies ligands to the protein as inhibitor candidates; (2) the second assay detects binding of a receptor protein with identical SMM and subsequent binding of the target protein (a sandwich assay) to identify the ligands to the receptor protein that do not interfere with the target-receptor binding; (3) the third assay detects binding of the target protein to the receptor protein in the presence of the ligands of the target protein identified from the first assay, with the receptor protein immobilized to a solid surface through the ligands identified in the second assay, to yield dose-response curves. Using this platform, we screened 7,961 compounds from the National Cancer Institute and found 12 inhibitors to VEGF-KDR (VEGFR2) interactions with IC50 ranging from 0.3 to 60 µM. The inhibitory potency of these inhibitors found in the microarray-based assay was confirmed by their inhibition of VEGF-induced VEGFR2 phosphorylation in a cell-based assay.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Peptídeos/química , Análise Serial de Proteínas/métodos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/química , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/química , Desenho de Fármacos , Ligantes , Ligação Proteica , Mapeamento de Interação de Proteínas/métodos , Coloração e Rotulagem
6.
PLoS One ; 5(2): e9072, 2010 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-20140208

RESUMO

Rabbit antibodies have been widely used in research and diagnostics due to their high antigen specificity and affinity. Though these properties are also highly desirable for therapeutic applications, rabbit antibodies have remained untapped for human disease therapy. To evaluate the therapeutic potential of rabbit monoclonal antibodies (RabMAbs), we generated a panel of neutralizing RabMAbs against human vascular endothelial growth factor-A (VEGF). These neutralizing RabMAbs are specific to VEGF and do not cross-react to other members of the VEGF protein family. Guided by sequence and lineage analysis of a panel of neutralizing RabMAbs, we humanized the lead candidate by substituting non-critical residues with human residues within both the frameworks and the CDR regions. We showed that the humanized RabMAb retained its parental biological properties and showed potent inhibition of the growth of H460 lung carcinoma and A673 rhabdomyosarcoma xenografts in mice. These studies provide proof of principle for the feasibility of developing humanized RabMAbs as therapeutics.


Assuntos
Anticorpos Monoclonais/farmacologia , Neoplasias/prevenção & controle , Neovascularização Patológica/prevenção & controle , Fator A de Crescimento do Endotélio Vascular/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Afinidade de Anticorpos/imunologia , Especificidade de Anticorpos/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Mapeamento de Epitopos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Dados de Sequência Molecular , Neoplasias/irrigação sanguínea , Neoplasias/patologia , Neovascularização Patológica/metabolismo , Fosforilação/efeitos dos fármacos , Coelhos , Homologia de Sequência de Aminoácidos , Carga Tumoral/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
7.
EMBO J ; 26(17): 3957-67, 2007 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-17673906

RESUMO

Erk1/Erk2 MAP kinases are key regulators of cell behaviour and their activation is generally associated with tyrosine kinase signalling. However, TGF-beta stimulation also activates Erk MAP kinases through an undefined mechanism, albeit to a much lower level than receptor tyrosine kinase stimulation. We report that upon TGF-beta stimulation, the activated TGF-beta type I receptor (TbetaRI) recruits and directly phosphorylates ShcA proteins on tyrosine and serine. This dual phosphorylation results from an intrinsic TbetaRI tyrosine kinase activity that complements its well-defined serine-threonine kinase function. TGF-beta-induced ShcA phosphorylation induces ShcA association with Grb2 and Sos, thereby initiating the well-characterised pathway linking receptor tyrosine kinases with Erk MAP kinases. We also found that TbetaRI is tyrosine phosphorylated in response to TGF-beta. Thus, TbetaRI, like the TGF-beta type II receptor, is a dual-specificity kinase. Recruitment of tyrosine kinase signalling pathways may account for aspects of TGF-beta biology that are independent of Smad signalling.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/fisiologia , Animais , Linhagem Celular , Ativação Enzimática , Proteína Adaptadora GRB2/metabolismo , Humanos , Camundongos , Fosforilação , Proteínas Adaptadoras da Sinalização Shc , Proteína Son Of Sevenless de Drosófila/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src
8.
J Biol Chem ; 278(30): 27853-63, 2003 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-12740389

RESUMO

Transforming growth factor-beta (TGF-beta) and TGF-beta-related factors regulate cell growth, differentiation, and apoptosis, and play key roles in normal development and tumorigenesis. TGF-beta family-induced changes in gene expression are mediated by serine/threonine kinase receptors at the cell surface and Smads as intracellular effectors. Receptor-activated Smads combine with a common Smad4 to translocate into the nucleus where they cooperate with other transcription factors to activate or repress transcription. The activities of the receptor-activated Smads are controlled by post-translational modifications such as phosphorylation and ubiquitylation. Here we show that Smad4 is modified by sumoylation. Sumoylation of Smad4 was enhanced by the conjugating enzyme Ubc9 and members of the PIAS family of SUMO ligases. A major sumoylation site in Smad4 was localized to Lys-159 in its linker segment with an additional site at Lys-113 in the MH-1 domain. Increased sumoylation in the presence of the PIASy E3 ligase correlated with targeting of Smad4 to subnuclear speckles that contain SUMO-1 and PIASy. Replacement of lysines 159 and 113 by arginines or increased sumoylation enhanced the stability of Smad4, and transcription in mammalian cells and Xenopus embryos. These observations suggest a role for Smad4 sumoylation in the regulation of TGF-beta signaling through Smads.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular , Proteína SUMO-1/metabolismo , Transdução de Sinais , Transativadores/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Enzimas de Conjugação de Ubiquitina , Proteínas de Xenopus , Transporte Ativo do Núcleo Celular , Animais , Arginina/química , Western Blotting , Células COS , Proteínas de Transporte/metabolismo , Proteínas de Ligação a DNA/metabolismo , Células HeLa , Humanos , Ligases/metabolismo , Lisina/química , Microscopia de Fluorescência , Fatores de Crescimento Neural , Plasmídeos/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose , Testes de Precipitina , Proteínas Inibidoras de STAT Ativados , Processamento de Proteína Pós-Traducional , Estrutura Terciária de Proteína , RNA Complementar/metabolismo , Proteínas Smad , Proteína Smad4 , Transativadores/metabolismo , Transcrição Gênica , Ativação Transcricional , Transfecção , Células Tumorais Cultivadas , Ubiquitina-Proteína Ligases , Xenopus
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