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1.
Cleft Palate Craniofac J ; 58(5): 653-657, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33356504

RESUMO

Multidisciplinary care in the era of COVID mitigation presented a unique opportunity to evolve a multidisciplinary Telehealth experience at the Children's Hospital Colorado. We describe our experience in developing unique programming to remain in compliance with an experience as recommended by the Parameters of Care while integrating information technology accessible via the electronic health record, multimedia adjuncts, and the integration of multiple institutional participants in creating a platform to offer care via Telehealth. Visit structure, planning, implementation, and advantages and disadvantages of the programming are discussed.


Assuntos
COVID-19 , Telemedicina , Criança , Colorado/epidemiologia , Humanos , Pandemias , SARS-CoV-2
2.
Proc Natl Acad Sci U S A ; 112(16): 5045-50, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25848042

RESUMO

Cells are dynamic systems capable of spontaneously switching among stable states. One striking example of this is spontaneous symmetry breaking and motility initiation in fish epithelial keratocytes. Although the biochemical and mechanical mechanisms that control steady-state migration in these cells have been well characterized, the mechanisms underlying symmetry breaking are less well understood. In this work, we have combined experimental manipulations of cell-substrate adhesion strength and myosin activity, traction force measurements, and mathematical modeling to develop a comprehensive mechanical model for symmetry breaking and motility initiation in fish epithelial keratocytes. Our results suggest that stochastic fluctuations in adhesion strength and myosin localization drive actin network flow rates in the prospective cell rear above a critical threshold. Above this threshold, high actin flow rates induce a nonlinear switch in adhesion strength, locally switching adhesions from gripping to slipping and further accelerating actin flow in the prospective cell rear, resulting in rear retraction and motility initiation. We further show, both experimentally and with model simulations, that the global levels of adhesion strength and myosin activity control the stability of the stationary state: The frequency of symmetry breaking decreases with increasing adhesion strength and increases with increasing myosin contraction. Thus, the relative strengths of two opposing mechanical forces--contractility and cell-substrate adhesion--determine the likelihood of spontaneous symmetry breaking and motility initiation.


Assuntos
Movimento Celular , Ciclídeos/metabolismo , Células Epiteliais/citologia , Miosinas/metabolismo , Actinas/metabolismo , Animais , Fenômenos Biomecânicos , Adesão Celular , Simulação por Computador , Dinâmica não Linear
3.
Plant Physiol ; 169(4): 2422-43, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26450706

RESUMO

Noble rot results from exceptional infections of ripe grape (Vitis vinifera) berries by Botrytis cinerea. Unlike bunch rot, noble rot promotes favorable changes in grape berries and the accumulation of secondary metabolites that enhance wine grape composition. Noble rot-infected berries of cv Sémillon, a white-skinned variety, were collected over 3 years from a commercial vineyard at the same time that fruit were harvested for botrytized wine production. Using an integrated transcriptomics and metabolomics approach, we demonstrate that noble rot alters the metabolism of cv Sémillon berries by inducing biotic and abiotic stress responses as well as ripening processes. During noble rot, B. cinerea induced the expression of key regulators of ripening-associated pathways, some of which are distinctive to the normal ripening of red-skinned cultivars. Enhancement of phenylpropanoid metabolism, characterized by a restricted flux in white-skinned berries, was a common outcome of noble rot and red-skinned berry ripening. Transcript and metabolite analyses together with enzymatic assays determined that the biosynthesis of anthocyanins is a consistent hallmark of noble rot in cv Sémillon berries. The biosynthesis of terpenes and fatty acid aroma precursors also increased during noble rot. We finally characterized the impact of noble rot in botrytized wines. Altogether, the results of this work demonstrated that noble rot causes a major reprogramming of berry development and metabolism. This desirable interaction between a fruit and a fungus stimulates pathways otherwise inactive in white-skinned berries, leading to a greater accumulation of compounds involved in the unique flavor and aroma of botrytized wines.


Assuntos
Antocianinas/metabolismo , Botrytis/fisiologia , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/microbiologia , Vitis/metabolismo , Frutas/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Interações Hospedeiro-Patógeno , Metabolômica , Vitis/crescimento & desenvolvimento , Vinho
4.
Nature ; 465(7296): 373-7, 2010 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-20485438

RESUMO

Crawling locomotion of eukaryotic cells is achieved by a process dependent on the actin cytoskeleton: protrusion of the leading edge requires assembly of a network of actin filaments, which must be disassembled at the cell rear for sustained motility. Although ADF/cofilin proteins have been shown to contribute to actin disassembly, it is not clear how activity of these locally acting proteins could be coordinated over the distance scale of the whole cell. Here we show that non-muscle myosin II has a direct role in actin network disassembly in crawling cells. In fish keratocytes undergoing motility, myosin II is concentrated in regions at the rear with high rates of network disassembly. Activation of myosin II by ATP in detergent-extracted cytoskeletons results in rear-localized disassembly of the actin network. Inhibition of myosin II activity and stabilization of actin filaments synergistically impede cell motility, suggesting the existence of two disassembly pathways, one of which requires myosin II activity. Our results establish the importance of myosin II as an enzyme for actin network disassembly; we propose that gradual formation and reorganization of an actomyosin network provides an intrinsic destruction timer, enabling long-range coordination of actin network treadmilling in motile cells.


Assuntos
Actinas/química , Actinas/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Miosina Tipo II/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Ciclídeos , Citoesqueleto/química , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Depsipeptídeos/farmacologia , Detergentes , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Miosina Tipo II/antagonistas & inibidores , Ligação Proteica/efeitos dos fármacos , Transporte Proteico
5.
Nature ; 453(7194): 475-80, 2008 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-18497816

RESUMO

The shape of motile cells is determined by many dynamic processes spanning several orders of magnitude in space and time, from local polymerization of actin monomers at subsecond timescales to global, cell-scale geometry that may persist for hours. Understanding the mechanism of shape determination in cells has proved to be extremely challenging due to the numerous components involved and the complexity of their interactions. Here we harness the natural phenotypic variability in a large population of motile epithelial keratocytes from fish (Hypsophrys nicaraguensis) to reveal mechanisms of shape determination. We find that the cells inhabit a low-dimensional, highly correlated spectrum of possible functional states. We further show that a model of actin network treadmilling in an inextensible membrane bag can quantitatively recapitulate this spectrum and predict both cell shape and speed. Our model provides a simple biochemical and biophysical basis for the observed morphology and behaviour of motile cells.


Assuntos
Movimento Celular/fisiologia , Forma Celular/fisiologia , Ciclídeos , Células Epiteliais/citologia , Citoesqueleto de Actina/química , Citoesqueleto de Actina/metabolismo , Actinas/química , Actinas/metabolismo , Animais , Fenômenos Biofísicos , Biofísica , Membrana Celular/química , Membrana Celular/metabolismo , Células Cultivadas , Modelos Biológicos , Pseudópodes/metabolismo , Fatores de Tempo
6.
J Clin Oncol ; : JCO2400071, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39028931

RESUMO

PURPOSE: To assess the safety and efficacy of the third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor osimertinib as neoadjuvant therapy in patients with surgically resectable stage I-IIIA EGFR-mutated non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: This was a multi-institutional phase II trial of neoadjuvant osimertinib for patients with surgically resectable stage I-IIIA (American Joint Committee on Cancer [AJCC] V7) EGFR-mutated (L858R or exon 19 deletion) NSCLC (ClinicalTrials.gov identifier: NCT03433469). Patients received osimertinib 80 mg orally once daily for up to two 28-day cycles before surgical resection. The primary end point was major pathological response (MPR) rate. Secondary safety and efficacy end points were also assessed. Exploratory end points included pretreatment and post-treatment tumor mutation profiling. RESULTS: A total of 27 patients were enrolled and treated with neoadjuvant osimertinib for a median 56 days before surgical resection. Twenty-four (89%) patients underwent subsequent surgery; three (11%) patients were converted to definitive chemoradiotherapy. The MPR rate was 14.8% (95% CI, 4.2 to 33.7). No pathological complete responses were observed. The ORR was 52%, and the median DFS was 40.9 months. One treatment-related serious adverse event (AE) occurred (3.7%). No patients were unable to undergo surgical resection or had surgery delayed because of an AE. The most common co-occurring tumor genomic alterations were in TP53 (42%) and RBM10 (21%). CONCLUSION: Treatment with neoadjuvant osimertinib in surgically resectable (stage IA-IIIA, AJCC V7) EGFR-mutated NSCLC did not meet its primary end point for MPR rate. However, neoadjuvant osimertinib did not lead to unanticipated AEs, surgical delays, nor result in a significant unresectability rate.

7.
Life Sci Alliance ; 6(8)2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37311583

RESUMO

Immunological targeting of pathological cells has been successful in oncology and is expanding to other pathobiological contexts. Here, we present a flexible platform that allows labeling cells of interest with the surface-expressed model antigen ovalbumin (OVA), which can be eliminated via either antigen-specific T cells or newly developed OVA antibodies. We demonstrate that hepatocytes can be effectively targeted by either modality. In contrast, pro-fibrotic fibroblasts associated with pulmonary fibrosis are only eliminated by T cells in initial experiments, which reduced collagen deposition in a fibrosis model. This new experimental platform will facilitate development of immune-based approaches to clear potential pathological cell types in vivo.


Assuntos
Anticorpos , Fibrose Pulmonar , Humanos , Fibroblastos , Hepatócitos , Cinética
9.
Nat Rev Cancer ; 22(12): 693-702, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36175644

RESUMO

In the past several decades, the development of cancer therapeutics has largely focused on precision targeting of single cancer-associated molecules. Despite great advances, such targeted therapies still show incomplete precision and the eventual development of resistance due to target heterogeneity or mutation. However, the recent development of cell-based therapies such as chimeric antigen receptor (CAR) T cells presents a revolutionary opportunity to reframe strategies for targeting cancers. Immune cells equipped with synthetic circuits are essentially living computers that can be programmed to recognize tumours based on multiple signals, including both tumour cell-intrinsic and microenvironmental. Moreover, cells can be programmed to launch broad but highly localized therapeutic responses that can limit the potential for escape while still maintaining high precision. Although these emerging smart cell engineering capabilities have yet to be fully implemented in the clinic, we argue here that they will become much more powerful when combined with machine learning analysis of genomic data, which can guide the design of therapeutic recognition programs that are the most discriminatory and actionable. The merging of cancer analytics and synthetic biology could lead to nuanced paradigms of tumour recognition, more akin to facial recognition, that have the ability to more effectively address the complex challenges of treating cancer.


Assuntos
Neoplasias , Humanos , Neoplasias/genética , Imunoterapia Adotiva , Engenharia Celular , Biologia Sintética
10.
Science ; 378(6625): eaba1624, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36520915

RESUMO

Chimeric antigen receptor (CAR) T cells are ineffective against solid tumors with immunosuppressive microenvironments. To overcome suppression, we engineered circuits in which tumor-specific synNotch receptors locally induce production of the cytokine IL-2. These circuits potently enhance CAR T cell infiltration and clearance of immune-excluded tumors, without systemic toxicity. The most effective IL-2 induction circuit acts in an autocrine and T cell receptor (TCR)- or CAR-independent manner, bypassing suppression mechanisms including consumption of IL-2 or inhibition of TCR signaling. These engineered cells establish a foothold in the target tumors, with synthetic Notch-induced IL-2 production enabling initiation of CAR-mediated T cell expansion and cell killing. Thus, it is possible to reconstitute synthetic T cell circuits that activate the outputs ultimately required for an antitumor response, but in a manner that evades key points of tumor suppression.


Assuntos
Terapia de Imunossupressão , Imunoterapia Adotiva , Interleucina-2 , Neoplasias , Receptores de Antígenos Quiméricos , Linfócitos T , Humanos , Imunoterapia Adotiva/métodos , Interleucina-2/genética , Interleucina-2/metabolismo , Neoplasias/imunologia , Neoplasias/terapia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/imunologia , Linfócitos T/transplante , Microambiente Tumoral , Animais , Camundongos , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Engenharia Celular , Receptores Notch/metabolismo , Terapia de Imunossupressão/métodos
11.
Neurocase ; 17(5): 425-39, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21590585

RESUMO

Individuals with dyslexia often demonstrate bilateral inferior frontal lobe activation while performing basic reading tasks. To investigate these findings, functional connectivity analyses were conducted on fMRI data collected from children with dyslexia, who did and did not respond well to treatment, and from non-impaired readers. Analysis of active and resting-state fMRI data across 15 participants revealed functional connections between the inferior frontal regions in non-impaired readers and treatment responders, but not in treatment non-responders. Analyses incorporating DTI data revealed associations with anterior corpus callosum structures. These results suggest that bilateral frontal functional connectivity is normative and may facilitate treatment response.


Assuntos
Dislexia/fisiopatologia , Lobo Frontal/anatomia & histologia , Lobo Frontal/fisiologia , Vias Neurais/fisiologia , Leitura , Adolescente , Criança , Feminino , Lobo Frontal/fisiopatologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Vias Neurais/anatomia & histologia , Testes Neuropsicológicos
12.
Biophys J ; 98(6): 933-42, 2010 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-20303850

RESUMO

Many complex cellular processes from mitosis to cell motility depend on the ability of the cytoskeleton to generate force. Force-generating systems that act on elastic cytoskeletal elements are prone to oscillating instabilities. In this work, we have measured spontaneous shape and movement oscillations in motile fish epithelial keratocytes. In persistently polarized, fan-shaped cells, retraction of the trailing edge on one side of the cell body is out of phase with retraction on the other side, resulting in periodic lateral oscillation of the cell body. We present a physical description of keratocyte oscillation in which periodic retraction of the trailing edge is the result of elastic coupling with the leading edge. Consistent with the predictions of this model, the observed frequency of oscillation correlates with cell speed. In addition, decreasing the strength of adhesion to the substrate reduces the elastic force required for retraction, causing cells to oscillate with higher frequency at relatively lower speeds. These results demonstrate that simple elastic coupling between movement at the front of the cell and movement at the rear can generate large-scale mechanical integration of cell behavior.


Assuntos
Relógios Biológicos/fisiologia , Biomimética/métodos , Movimento Celular/fisiologia , Locomoção/fisiologia , Modelos Biológicos , Animais , Células Cultivadas , Simulação por Computador , Peixes
13.
Cell Syst ; 11(3): 286-299.e4, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32916096

RESUMO

Motile cells navigate complex environments by changing their direction of travel, generating left-right asymmetries in their mechanical subsystems to physically turn. Currently, little is known about how external directional cues are propagated along the length scale of the whole cell and integrated with its force-generating apparatus to steer migration mechanically. We examine the mechanics of spontaneous cell turning in fish epidermal keratocytes and find that the mechanical asymmetries responsible for turning behavior predominate at the rear of the cell, where there is asymmetric centripetal actin flow. Using experimental perturbations, we identify two linked feedback loops connecting myosin II contractility, adhesion strength and actin network flow in turning cells that are sufficient to explain the observed cell shapes and trajectories. Notably, asymmetries in actin polymerization at the cell leading edge play only a minor role in the mechanics of cell turning-that is, cells steer from the rear.


Assuntos
Movimento Celular/fisiologia , Forma Celular/fisiologia , Modelos Biológicos , Humanos
14.
Science ; 370(6520): 1099-1104, 2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-33243890

RESUMO

Living cells often identify their correct partner or target cells by integrating information from multiple receptors, achieving levels of recognition that are difficult to obtain with individual molecular interactions. In this study, we engineered a diverse library of multireceptor cell-cell recognition circuits by using synthetic Notch receptors to transcriptionally interconnect multiple molecular recognition events. These synthetic circuits allow engineered T cells to integrate extra- and intracellular antigen recognition, are robust to heterogeneity, and achieve precise recognition by integrating up to three different antigens with positive or negative logic. A three-antigen AND gate composed of three sequentially linked receptors shows selectivity in vivo, clearing three-antigen tumors while ignoring related two-antigen tumors. Daisy-chaining multiple molecular recognition events together in synthetic circuits provides a powerful way to engineer cellular-level recognition.


Assuntos
Comunicação Celular/imunologia , Engenharia Celular , Receptores de Antígenos Quiméricos/imunologia , Receptores Notch/imunologia , Linfócitos T/imunologia , Animais , Antígenos de Neoplasias/imunologia , Humanos , Camundongos , Receptores de Antígenos Quiméricos/genética , Receptores Notch/genética , Transcrição Gênica
15.
Cytokine X ; 2(4): 100035, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32895645

RESUMO

The SARS-CoV-2 virus responsible for the COVID-19 pandemic can result in severe or fatal disease in a subset of infected patients. While the pathogenesis of severe COVID-19 disease has yet to be fully elucidated, an overexuberant and harmful immune response to the SARS-CoV-2 virus may be a pivotal aspect of critical illness in this patient population. The inflammatory cytokine, IL-6, has been found to be consistently elevated in severely ill COVID-19 patients, prompting speculation that IL-6 is an important driver of the pathologic process. The inappropriately elevated levels of inflammatory cytokines in COVID-19 patients is similar to cytokine release syndrome (CRS) observed in cell therapy patients. We sought to describe outcomes in a series of severely ill patients with COVID-19 CRS following treatment with anti-IL-6/IL-6-Receptor (anti-IL-6/IL-6-R) therapy, including tocilizumab or siltuximab. At our academic community medical center, we formed a multi-disciplinary committee for selecting severely ill COVID-19 patients for therapy with anti-IL-6 or IL-6-R agents. Key selection criteria included evidence of hyperinflammation, most notably elevated levels of C-reactive protein (CRP) and ferritin, and an increasing oxygen requirement. By the data cutoff point, we treated 31 patients with anti-IL-6/IL-6-R agents including 12 who had already been intubated. Overall, 27 (87%) patients are alive and 24 (77%) have been discharged from the hospital. Clinical responses to anti-IL-6/IL-6-R therapy were accompanied by significant decreases in temperature, oxygen requirement, CRP, IL-6, and IL-10 levels. Based on these data, we believe anti-IL-6/IL-6-R therapy can be effective in managing early CRS related to COVID-19 disease. Further study of anti-IL-6/IL-6-R therapy alone and in combination with other classes of therapeutics is warranted and trials are underway.

16.
Arch Neurol ; 64(10): 1482-7, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17923631

RESUMO

OBJECTIVE: To determine if functional connectivity of the hippocampus is reduced in patients with Alzheimer disease. DESIGN: Functional connectivity magnetic resonance imaging was used to investigate coherence in the magnetic resonance signal between the hippocampus and all other regions of the brain. PARTICIPANTS: Eight patients with probable Alzheimer disease and 8 healthy volunteers. RESULTS: Control subjects showed hippocampal functional connectivity with diffuse cortical, subcortical, and cerebellar sites, while patients demonstrated markedly reduced functional connectivity, including an absence of connectivity with the frontal lobes. CONCLUSION: These findings suggest a functional disconnection between the hippocampus and other brain regions in patients with Alzheimer disease.


Assuntos
Doença de Alzheimer/patologia , Hipocampo/patologia , Idoso , Cerebelo/patologia , Interpretação Estatística de Dados , Feminino , Lobo Frontal/patologia , Lateralidade Funcional/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória/fisiologia , Vias Neurais/patologia , Testes Neuropsicológicos
17.
mBio ; 7(3)2016 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-27302757

RESUMO

UNLABELLED: Regionally distinct wine characteristics (terroir) are an important aspect of wine production and consumer appreciation. Microbial activity is an integral part of wine production, and grape and wine microbiota present regionally defined patterns associated with vineyard and climatic conditions, but the degree to which these microbial patterns associate with the chemical composition of wine is unclear. Through a longitudinal survey of over 200 commercial wine fermentations, we demonstrate that both grape microbiota and wine metabolite profiles distinguish viticultural area designations and individual vineyards within Napa and Sonoma Counties, California. Associations among wine microbiota and fermentation characteristics suggest new links between microbiota, fermentation performance, and wine properties. The bacterial and fungal consortia of wine fermentations, composed from vineyard and winery sources, correlate with the chemical composition of the finished wines and predict metabolite abundances in finished wines using machine learning models. The use of postharvest microbiota as an early predictor of wine chemical composition is unprecedented and potentially poses a new paradigm for quality control of agricultural products. These findings add further evidence that microbial activity is associated with wine terroir IMPORTANCE: Wine production is a multi-billion-dollar global industry for which microbial control and wine chemical composition are crucial aspects of quality. Terroir is an important feature of consumer appreciation and wine culture, but the many factors that contribute to terroir are nebulous. We show that grape and wine microbiota exhibit regional patterns that correlate with wine chemical composition, suggesting that the grape microbiome may influence terroir In addition to enriching our understanding of how growing region and wine properties interact, this may provide further economic incentive for agricultural and enological practices that maintain regional microbial biodiversity.


Assuntos
Bactérias/metabolismo , Fungos/metabolismo , Metaboloma , Microbiota , Vitis/microbiologia , Vinho/análise , Bactérias/classificação , Bactérias/crescimento & desenvolvimento , California , Fermentação , Fungos/classificação , Fungos/crescimento & desenvolvimento , Estudos Longitudinais
18.
Biol Psychiatry ; 56(4): 269-78, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15312815

RESUMO

BACKGROUND: The cerebellum is one of the most consistent sites of neuroanatomic abnormality in autism, yet it is still unclear how such pathology impacts cerebellar function. In normal subjects, we previously demonstrated with functional magnetic resonance imaging (fMRI) a dissociation between cerebellar regions involved in attention and those involved in a simple motor task, with motor activation localized to the anterior cerebellum ipsilateral to the moving hand. The purpose of the present investigation was to examine activation in the cerebella of autistic patients and normal control subjects performing this motor task. METHODS: We studied eight autistic patients and eight matched normal subjects, using fMRI. An anatomic region-of-interest approach was used, allowing a detailed examination of cerebellar function. RESULTS: Autistic individuals showed significantly increased motor activation in the ipsilateral anterior cerebellar hemisphere relative to normal subjects, in addition to atypical activation in contralateral and posterior cerebellar regions. Moreover, increased activation was correlated with the degree of cerebellar structural abnormality. CONCLUSIONS: These findings strongly suggest dysfunction of the autistic cerebellum that is a reflection of cerebellar anatomic abnormality. This neurofunctional deficit might be a key contributor to the development of certain diagnostic features of autism (e.g., impaired communication and social interaction, restricted interests, and stereotyped behaviors).


Assuntos
Transtorno Autístico/fisiopatologia , Cerebelo/fisiopatologia , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Mapeamento Encefálico , Estudos de Casos e Controles , Cerebelo/irrigação sanguínea , Cerebelo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Oxigênio/sangue , Análise de Regressão
19.
Am J Psychiatry ; 160(2): 262-73, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12562572

RESUMO

OBJECTIVE: Recent years have seen a revolution in views regarding cerebellar function. New findings suggest that the cerebellum plays a role in multiple functional domains: cognitive, affective, and sensory as well as motor. These findings imply that developmental cerebellar pathology could play a role in certain nonmotor functional deficits, thereby calling for a broader investigation of the functional consequences of cerebellar pathology. Autism provides a useful model, since over 90% of autistic cerebella examined at autopsy have shown well-defined cerebellar anatomic abnormalities. The aim of the present study was to examine how such pathology ultimately impacts cognitive and motor function within the cerebellum. METHOD: Patterns of functional magnetic resonance imaging (fMRI) activation within anatomically defined cerebellar regions of interest were examined in eight autistic patients (ages 14-38 years) and eight matched healthy comparison subjects performing motor and attention tasks. For the motor task, subjects pressed a button at a comfortable pace, and activation was compared with a rest condition. For the attention task, visual stimuli were presented one at a time at fixation, and subjects pressed a button to every target. Activation was compared with passive visual stimulation. RESULTS: While performing these tasks, autistic individuals showed significantly greater cerebellar motor activation and significantly less cerebellar attention activation. CONCLUSIONS: These findings shed new light on the cerebellar role in attention deficits in autism and suggest that developmental cerebellar abnormality has differential functional implications for cognitive and motor systems.


Assuntos
Transtorno Autístico/diagnóstico , Cerebelo/fisiopatologia , Imageamento por Ressonância Magnética/estatística & dados numéricos , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Atenção/fisiologia , Transtorno Autístico/fisiopatologia , Mapeamento Encefálico , Cerebelo/anatomia & histologia , Cerebelo/fisiologia , Córtex Cerebral/fisiopatologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Modelos Neurológicos , Destreza Motora/fisiologia , Redes Neurais de Computação , Plasticidade Neuronal/fisiologia
20.
Curr Biol ; 23(7): 560-8, 2013 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-23541731

RESUMO

BACKGROUND: Motile cells exposed to an external direct current electric field will reorient and migrate along the direction of the electric potential in a process known as galvanotaxis. The underlying physical mechanism that allows a cell to sense an electric field is unknown, although several plausible hypotheses have been proposed. In this work we evaluate the validity of each of these mechanisms. RESULTS: We find that the directional motile response of fish epidermal cells to the cathode in an electric field does not require extracellular sodium or potassium, is insensitive to membrane potential, and is also insensitive to perturbation of calcium, sodium, hydrogen, or chloride ion transport across the plasma membrane. Cells migrate in the direction of applied forces from laminar fluid flow, but reversal of electro-osmotic flow did not affect the galvanotactic response. Galvanotaxis fails when extracellular pH is below 6, suggesting that the effective charge of membrane components might be a crucial factor. Slowing the migration of membrane components with an increase in aqueous viscosity slows the kinetics of the galvanotactic response. In addition, inhibition of PI3K reverses the cell's response to the anode, suggesting the existence of multiple signaling pathways downstream of the galvanotactic signal. CONCLUSIONS: Our results are most consistent with the hypothesis that electrophoretic redistribution of membrane components of the motile cell is the primary physical mechanism for motile cells to sense an electric field. This chemical polarization of the cellular membrane is then transduced by intracellular signaling pathways canonical to chemotaxis to dictate the cell's direction of travel.


Assuntos
Membrana Celular/fisiologia , Movimento Celular/fisiologia , Ceratócitos da Córnea/fisiologia , Sinais (Psicologia) , Eletricidade , Transdução de Sinais/fisiologia , Animais , Ciclídeos , Ceratócitos da Córnea/metabolismo , Estimulação Elétrica , Campos Eletromagnéticos , Eletroforese/métodos , Concentração de Íons de Hidrogênio , Cinética , Fosfatidilinositol 3-Quinases/metabolismo
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