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1.
Psychogeriatrics ; 23(3): 503-511, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37005070

RESUMO

BACKGROUND: Behavioural and psychological symptoms of dementia (BPSD) are challenging to manage, leading to caregiver burden and often to subsequent transfer of patients to a nursing home or psychiatric hospital for treatment. Eliciting favourable positive emotions should be an important goal in the treatment of negative emotions associated with BPSD. To date, no data have indicated that antipsychotic medications can improve positive emotions. BPSD are known to be associated with anxiety in patients with dementia. The traditional Chinese medicine Jia Wei Gui Pi Tang is officially indicated and approved for anxiety treatment in Japan. METHODS: Here, we performed a multicentre, randomised, observer-blind control study of the effect of Jia Wei Gui Pi Tang on BPSD in Alzheimer's disease (AD) patients. Patients with AD or AD with cerebral vascular disease were randomly divided into the Jia Wei Gui Pi Tang treatment group and the control group that received no traditional Chinese medicine. BPSD were scored using the Neuropsychiatric Inventory Nursing Home Version (NPI-NH) and by favourable positive emotions using the Delightful Emotional Index (DEI). RESULTS: A total of 63 participants (18 male and 45 female; mean age: 83.3 ± 6.0 years) were included in the study. Changes in NPI-NH scores differed significantly between the two groups (one-way analysis of variance, P < 0.001). Within the treatment group, there was a significant improvement in the NPI-NH score from 29.8 ± 17.3 at baseline to 13.2 ± 9.4 at the endpoint (paired t-test, P < 0.001), whereas there was no statistically significant change in the control group. Changes in DEI scores differed significantly between the two groups. Within the treatment group, there was a significant improvement in the DEI score from 24.3 ± 23.0 at baseline to 32.5 ± 21.2 at the endpoint (paired t-test, P = 0.001), whereas there was no statistically significant change in the control group. CONCLUSION: The traditional Chinese medicine Jia Wei Gui Pi Tang significantly improved both BPSD and positive emotions.


Assuntos
Doença de Alzheimer , Demência , Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Demência/psicologia , Medicina Tradicional Chinesa , Doença de Alzheimer/psicologia , Casas de Saúde , Emoções
2.
Biochem Biophys Res Commun ; 521(3): 706-715, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31699371

RESUMO

Each cell comprising an intact, healthy, confluent epithelial layer ordinarily remains sedentary, firmly adherent to and caged by its neighbors, and thus defines an elemental constituent of a solid-like cellular collective [1,2]. After malignant transformation, however, the cellular collective can become fluid-like and migratory, as evidenced by collective motions that arise in characteristic swirls, strands, ducts, sheets, or clusters [3,4]. To transition from a solid-like to a fluid-like phase and thereafter to migrate collectively, it has been recently argued that cells comprising the disordered but confluent epithelial collective can undergo changes of cell shape so as to overcome geometric constraints attributable to the newly discovered phenomenon of cell jamming and the associated unjamming transition (UJT) [1,2,5-9]. Relevance of the jamming concept to carcinoma cells lines of graded degrees of invasive potential has never been investigated, however. Using classical in vitro cultures of six breast cancer model systems, here we investigate structural and dynamical signatures of cell jamming, and the relationship between them [1,2,10,11]. In order of roughly increasing invasive potential as previously reported, model systems examined included MCF10A, MCF10A.Vector; MCF10A.14-3-3ζ; MCF10.ErbB2, MCF10AT; and MCF10CA1a [12-15]. Migratory speed depended on the particular cell line. Unsurprisingly, for example, the MCF10CA1a cell line exhibited much faster migratory speed relative to the others. But unexpectedly, across different cell lines higher speeds were associated with enhanced size of cooperative cell packs in a manner reminiscent of a peloton [9]. Nevertheless, within each of the cell lines evaluated, cell shape and shape variability from cell-to-cell conformed with predicted structural signatures of cell layer unjamming [1]. Moreover, both structure and migratory dynamics were compatible with previous theoretical descriptions of the cell jamming mechanism [2,10,11,16,17]. As such, these findings demonstrate the richness of the cell jamming mechanism, which is now seen to apply across these cancer cell lines but remains poorly understood.


Assuntos
Neoplasias da Mama/patologia , Movimento Celular , Invasividade Neoplásica/patologia , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Forma Celular , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Feminino , Humanos
3.
Nature ; 506(7488): 367-70, 2014 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-24336209

RESUMO

The unidirectional airflow patterns in the lungs of birds have long been considered a unique and specialized trait associated with the oxygen demands of flying, their endothermic metabolism and unusual pulmonary architecture. However, the discovery of similar flow patterns in the lungs of crocodilians indicates that this character is probably ancestral for all archosaurs--the group that includes extant birds and crocodilians as well as their extinct relatives, such as pterosaurs and dinosaurs. Unidirectional flow in birds results from aerodynamic valves, rather than from sphincters or other physical mechanisms, and similar aerodynamic valves seem to be present in crocodilians. The anatomical and developmental similarities in the primary and secondary bronchi of birds and crocodilians suggest that these structures and airflow patterns may be homologous. The origin of this pattern is at least as old as the split between crocodilians and birds, which occurred in the Triassic period. Alternatively, this pattern of flow may be even older; this hypothesis can be tested by investigating patterns of airflow in members of the outgroup to birds and crocodilians, the Lepidosauromorpha (tuatara, lizards and snakes). Here we demonstrate region-specific unidirectional airflow in the lungs of the savannah monitor lizard (Varanus exanthematicus). The presence of unidirectional flow in the lungs of V. exanthematicus thus gives rise to two possible evolutionary scenarios: either unidirectional airflow evolved independently in archosaurs and monitor lizards, or these flow patterns are homologous in archosaurs and V. exanthematicus, having evolved only once in ancestral diapsids (the clade encompassing snakes, lizards, crocodilians and birds). If unidirectional airflow is plesiomorphic for Diapsida, this respiratory character can be reconstructed for extinct diapsids, and evolved in a small ectothermic tetrapod during the Palaeozoic era at least a hundred million years before the origin of birds.


Assuntos
Evolução Biológica , Lagartos/fisiologia , Pulmão/fisiologia , Respiração , Jacarés e Crocodilos/fisiologia , Animais , Aves/fisiologia , Brônquios/anatomia & histologia , Brônquios/fisiologia , Dinossauros/fisiologia , Ecossistema , Feminino , Lagartos/anatomia & histologia , Pulmão/anatomia & histologia , Filogenia
4.
Tohoku J Exp Med ; 252(3): 263-267, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33177265

RESUMO

Behavioral and psychological symptoms of dementia (BPSD) challenge caregivers, leading to caregiver burden and subsequent nursing home or inpatient placement in a psychiatric hospital for dementia. Favorable positive emotions should be an important goal for the treatment of negative emotions of BPSD. Arts are one of the most profound areas to stimulate favorable emotions. We have asked a professional actor, who was not involved in the daily care and regular rehabilitations, to give a dramatic performance by reading selected stories as if the patients with BPSD felt to be in the audiences of a theater. We wondered whether a dramatic performance by the actor might be a way to respond to the complex needs of inpatients with BPSD, especially focused on favorable emotions. New inpatients (Alzheimer's disease, vascular dementia, or dementia with Lewy bodies) were randomly assigned to a control group (n = 20) and a dramatic performance group (n = 14) in Sendai Tomizawa Hospital, a psychiatric hospital for dementia, in Japan. Dramatic performances were performed for one and half hours once per week for 3 months. Neuropsychiatric Inventory for BPSD decreased in both groups and delightful emotional index (DEI) for favorable emotions increased in the intervention group but not in the control group after 3 months. At 3 months, there was an increase of DEI in intervention group compared with control group. We conclude that dramatic performance may be one of the appropriate interventions in patients with BPSD, as it appears to help in their favorable emotional state.


Assuntos
Doença de Alzheimer/terapia , Cuidadores , Demência Vascular/terapia , Drama , Emoções , Geriatria/métodos , Doença por Corpos de Lewy/terapia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Demência Vascular/psicologia , Feminino , Humanos , Pacientes Internados , Japão , Doença por Corpos de Lewy/psicologia , Masculino , Escalas de Graduação Psiquiátrica
6.
Psychogeriatrics ; 19(4): 320-324, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30784147

RESUMO

AIM: To characterise the effects of antipsychotics on brain functions of patients with behavioural psychological symptoms of dementia (BPSD). METHODS: Studies were performed during 6 weeks of intervention with either a nonantipsychotic drug (group A, n = 38) or an antipsychotic drug (group B, n = 10). RESULTS: Neuropsychiatric Inventory scores were significantly decreased in both groups. Scores on the Mini-Mental State Examination did not change with intervention. By contrast, favourable natures of emotional functions, scored using the Delightful Emotional Index of 10 items, were significantly lower in the antipsychotic drug treatment group B relative to scores in the nonantipsychotic drug treatment group A. CONCLUSIONS: Antipsychotics reduce favourite emotions as well as BPSD, and this should be considered in prescribing medications for patients with dementia.


Assuntos
Antipsicóticos/farmacologia , Sintomas Comportamentais/tratamento farmacológico , Demência/tratamento farmacológico , Uso Off-Label , Avaliação de Resultados em Cuidados de Saúde , Psicotrópicos/farmacologia , Idoso , Idoso de 80 Anos ou mais , Ansiolíticos/farmacologia , Anticonvulsivantes/farmacologia , Antidepressivos/farmacologia , Sintomas Comportamentais/etiologia , Demência/complicações , Feminino , Seguimentos , Humanos , Masculino , Testes de Estado Mental e Demência , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença
8.
Am J Physiol Lung Cell Mol Physiol ; 315(5): L645-L652, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30070589

RESUMO

During acute bronchoconstriction, the airway epithelium becomes mechanically compressed, as airway smooth muscle contracts and the airway narrows. This mechanical compression activates airway epithelium to promote asthmatic airway remodeling. However, whether compressed airway epithelium can feed back on the cause of bronchoconstriction has remained an open question. Here we examine the potential for epithelial compression to augment proliferation and contraction of airway smooth muscle, and thus potentiate further bronchoconstriction and epithelial compression. Well-differentiated primary human bronchial epithelial (HBE) cells maintained in air-liquid interface culture were mechanically compressed to mimic the effect of bronchoconstriction. Primary human airway smooth muscle (HASM) cells were incubated with conditioned media collected from mechanically compressed HBE cells to examine the effect of epithelial-derived mediators on HASM cell proliferation using an EdU assay and HASM cell contraction using traction microscopy. An endothelin receptor antagonist, PD-145065, was employed to probe the role of HBE cell-derived endothelin-1 on the proliferation and contraction of HASM cells. Conditioned media from compressed HBE cells increased HASM cell proliferation, independent of the endothelin-1 signaling pathway. However, conditioned media from compressed HBE cells significantly increased HASM cell basal contraction and histamine-induced contraction, both of which depended on the endothelin-1 signaling pathway. Our data demonstrate that mechanical compression of bronchial epithelial cells contributes to proliferation and basal contraction of airway smooth muscle cells and that augmented contraction depends on epithelial cell-derived endothelin-1. By means of both airway smooth muscle remodeling and contractility, our findings suggest a causal role of epithelial compression on asthma pathogenesis.


Assuntos
Remodelação das Vias Aéreas/fisiologia , Asma/patologia , Broncoconstrição/fisiologia , Proliferação de Células , Contração Muscular , Músculo Liso/fisiologia , Sistema Respiratório/patologia , Asma/metabolismo , Células Cultivadas , Endotelina-1/metabolismo , Humanos , Músculo Liso/citologia , Sistema Respiratório/metabolismo , Transdução de Sinais
9.
Am J Physiol Lung Cell Mol Physiol ; 314(5): L799-L807, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29345194

RESUMO

With every deep inspiration (DI) or sigh, the airway wall stretches, as do the airway smooth muscle cells in the airway wall. In response, the airway smooth muscle cell undergoes rapid stretch-induced cytoskeletal fluidization. As a molecular mechanism underlying the cytoskeletal fluidization response, we demonstrate a key role for the actin-severing protein cofilin. Using primary human airway smooth muscle cells, we simulated a DI by imposing a transient stretch of physiological magnitude and duration. We used traction microscopy to measure the resulting changes in contractile forces. After a transient stretch, cofilin-knockdown cells exhibited a 29 ± 5% decrease in contractile force compared with prestretch conditions. By contrast, control cells exhibited a 67 ± 6% decrease ( P < 0.05, knockdown vs. control). Consistent with these contractile force changes with transient stretch, actin filaments in cofilin-knockdown cells remained largely intact, whereas actin filaments in control cells were rapidly disrupted. Furthermore, in cofilin-knockdown cells, contractile force at baseline was higher and rate of remodeling poststretch was slower than in control cells. Additionally, the severing action of cofilin was restricted to the release phase of the transient stretch. We conclude that the actin-severing activity of cofilin is an important factor in stretch-induced cytoskeletal fluidization and may account for an appreciable part of the bronchodilatory effects of a DI.


Assuntos
Citoesqueleto de Actina/fisiologia , Cofilina 1/metabolismo , Citoesqueleto/fisiologia , Contração Muscular/fisiologia , Miócitos de Músculo Liso/fisiologia , Sistema Respiratório/metabolismo , Células Cultivadas , Cofilina 1/antagonistas & inibidores , Cofilina 1/genética , Humanos , Mecanotransdução Celular , Miócitos de Músculo Liso/citologia , RNA Interferente Pequeno/genética , Sistema Respiratório/citologia , Reologia
10.
J Cell Sci ; 129(18): 3375-83, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27550520

RESUMO

Collective cellular migration within the epithelial layer impacts upon development, wound healing and cancer invasion, but remains poorly understood. Prevailing conceptual frameworks tend to focus on the isolated role of each particular underlying factor - taken one at a time or at most a few at a time - and thus might not be tailored to describe a cellular collective that embodies a wide palette of physical and molecular interactions that are both strong and complex. To bridge this gap, we shift the spotlight to the emerging concept of cell jamming, which points to only a small set of parameters that govern when a cellular collective might jam and rigidify like a solid, or instead unjam and flow like a fluid. As gateways to cellular migration, the unjamming transition (UJT) and the epithelial-to-mesenchymal transition (EMT) share certain superficial similarities, but their congruence - or lack thereof - remains unclear. In this Commentary, we discuss aspects of cell jamming, its established role in human epithelial cell layers derived from the airways of non-asthmatic and asthmatic donors, and its speculative but emerging roles in development and cancer cell invasion.


Assuntos
Asma/patologia , Movimento Celular , Desenvolvimento Embrionário , Neoplasias/patologia , Animais , Transição Epitelial-Mesenquimal , Epitélio/patologia , Humanos
11.
Biochem Biophys Res Commun ; 495(1): 749-754, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29137986

RESUMO

In endothelial gap formation, local tractions exerted by the cell upon its basal adhesions are thought to exceed balancing tensile stresses exerted across the cell-cell junction, thus causing the junction to rupture. To test this idea, we mapped evolving tractions, intercellular stresses, and corresponding growth of paracellular gaps in response to agonist challenge. Contrary to expectation, we found little to no relationship between local tensile stresses and gap formation. Instead, we discovered that intercellular stresses were aligned into striking multi-cellular domains punctuated by defects in stress alignment. Surprisingly, gaps emerged preferentially not at stress hotspots, as predicted, but rather at stress defects. This unexpected behavior is captured by a minimal model of the cell layer as a jammed assembly of cohesive particles undergoing plastic rearrangements under tension. Together, experiments and model suggest a new physical picture in which gap formation, and its consequent effect on endothelial permeability, is determined not by a local stress imbalance at a cell-cell junction but rather by emergence of non-local, cooperative stress reorganization across the cellular collective.


Assuntos
Adesão Celular/fisiologia , Permeabilidade da Membrana Celular/fisiologia , Células Endoteliais/fisiologia , Junções Comunicantes/fisiologia , Mecanotransdução Celular/fisiologia , Modelos Cardiovasculares , Células Cultivadas , Simulação por Computador , Humanos , Resistência ao Cisalhamento , Estresse Mecânico
12.
Eur Respir J ; 52(3)2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30139771

RESUMO

A possible precision-medicine approach to treating obstructive sleep apnoea (OSA) involves targeting ventilatory instability (elevated loop gain) using supplemental inspired oxygen in selected patients. Here we test whether elevated loop gain and three key endophenotypic traits (collapsibility, compensation and arousability), quantified using clinical polysomnography, can predict the effect of supplemental oxygen on OSA severity.36 patients (apnoea-hypopnoea index (AHI) >20 events·h-1) completed two overnight polysomnographic studies (single-blinded randomised-controlled crossover) on supplemental oxygen (40% inspired) versus sham (air). OSA traits were quantified from the air-night polysomnography. Responders were defined by a ≥50% reduction in AHI (supine non-rapid eye movement). Secondary outcomes included blood pressure and self-reported sleep quality.Nine of 36 patients (25%) responded to supplemental oxygen (ΔAHI=72±5%). Elevated loop gain was not a significant univariate predictor of responder/non-responder status (primary analysis). In post hoc analysis, a logistic regression model based on elevated loop gain and other traits (better collapsibility and compensation; cross-validated) had 83% accuracy (89% before cross-validation); predicted responders exhibited an improvement in OSA severity (ΔAHI 59±6% versus 12±7% in predicted non-responders, p=0.0001) plus lowered morning blood pressure and "better" self-reported sleep.Patients whose OSA responds to supplemental oxygen can be identified by measuring their endophenotypic traits using diagnostic polysomnography.


Assuntos
Oxigenoterapia , Apneia Obstrutiva do Sono/terapia , Terapia Combinada , Pressão Positiva Contínua nas Vias Aéreas , Estudos Cross-Over , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Polissonografia , Método Simples-Cego , Apneia Obstrutiva do Sono/diagnóstico , Resultado do Tratamento
13.
Connect Tissue Res ; 59(4): 309-315, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28945485

RESUMO

At the edge of a confluent cell layer, cell-free empty space is a cue that can drive directed collective cellular migration. Similarly, contact guidance is also a robust mechanical cue that can drive cell migration. However, it is unclear which of the two effects is stronger, and how each mechanism affects collective migration. To address this question, here we explore the trajectories of cells migrating collectively on a substrate containing micropatterned grooves (10-20 µm in periodicity, 2 µm in height) compared with unpatterned control substrates. Compared with unpatterned controls, the micropatterned substrates attenuated path variance by close to 70% and augmented migration coordination by more than 30%. Together, these results show that contact guidance can play an appreciable role in collective cellular migration. Also, our result can provide insights into tissue repair and regeneration with the remodeling of the connective tissue matrix.


Assuntos
Movimento Celular , Células Epiteliais/citologia , Animais , Cães , Processamento de Imagem Assistida por Computador , Células Madin Darby de Rim Canino , Fatores de Tempo
14.
PLoS Comput Biol ; 13(10): e1005759, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29073206

RESUMO

Sleep loss causes profound cognitive impairments and increases the concentrations of adenosine and adenosine A1 receptors in specific regions of the brain. Time courses for performance impairment and recovery differ between acute and chronic sleep loss, but the physiological basis for these time courses is unknown. Adenosine has been implicated in pathways that generate sleepiness and cognitive impairments, but existing mathematical models of sleep and cognitive performance do not explicitly include adenosine. Here, we developed a novel receptor-ligand model of the adenosine system to test the hypothesis that changes in both adenosine and A1 receptor concentrations can capture changes in cognitive performance during acute sleep deprivation (one prolonged wake episode), chronic sleep restriction (multiple nights with insufficient sleep), and subsequent recovery. Parameter values were estimated using biochemical data and reaction time performance on the psychomotor vigilance test (PVT). The model closely fit group-average PVT data during acute sleep deprivation, chronic sleep restriction, and recovery. We tested the model's ability to reproduce timing and duration of sleep in a separate experiment where individuals were permitted to sleep for up to 14 hours per day for 28 days. The model accurately reproduced these data, and also correctly predicted the possible emergence of a split sleep pattern (two distinct sleep episodes) under these experimental conditions. Our findings provide a physiologically plausible explanation for observed changes in cognitive performance and sleep during sleep loss and recovery, as well as a new approach for predicting sleep and cognitive performance under planned schedules.


Assuntos
Adenosina/metabolismo , Encéfalo/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Cognição , Modelos Neurológicos , Privação do Sono/fisiopatologia , Sono , Atenção , Transtornos Cognitivos/etiologia , Simulação por Computador , Humanos , Desempenho Psicomotor , Tempo de Reação , Recuperação de Função Fisiológica , Privação do Sono/complicações
15.
Am J Respir Crit Care Med ; 195(2): 237-246, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27559818

RESUMO

RATIONALE: In patients with chronic heart failure, daytime oscillatory breathing at rest is associated with a high risk of mortality. Experimental evidence, including exaggerated ventilatory responses to CO2 and prolonged circulation time, implicates the ventilatory control system and suggests feedback instability (loop gain > 1) is responsible. However, daytime oscillatory patterns often appear remarkably irregular versus classic instability (Cheyne-Stokes respiration), suggesting our mechanistic understanding is limited. OBJECTIVES: We propose that daytime ventilatory oscillations generally result from a chemoreflex resonance, in which spontaneous biological variations in ventilatory drive repeatedly induce temporary and irregular ringing effects. Importantly, the ease with which spontaneous biological variations induce irregular oscillations (resonance "strength") rises profoundly as loop gain rises toward 1. We tested this hypothesis through a comparison of mathematical predictions against actual measurements in patients with heart failure and healthy control subjects. METHODS: In 25 patients with chronic heart failure and 25 control subjects, we examined spontaneous oscillations in ventilation and separately quantified loop gain using dynamic inspired CO2 stimulation. MEASUREMENTS AND MAIN RESULTS: Resonance was detected in 24 of 25 patients with heart failure and 18 of 25 control subjects. With increased loop gain-consequent to increased chemosensitivity and delay-the strength of spontaneous oscillations increased precipitously as predicted (r = 0.88), yielding larger (r = 0.78) and more regular (interpeak interval SD, r = -0.68) oscillations (P < 0.001 for all, both groups combined). CONCLUSIONS: Our study elucidates the mechanism underlying daytime ventilatory oscillations in heart failure and provides a means to measure and interpret these oscillations to reveal the underlying chemoreflex hypersensitivity and reduced stability that foretells mortality in this population.


Assuntos
Ritmo Circadiano/fisiologia , Insuficiência Cardíaca/fisiopatologia , Taxa Respiratória/fisiologia , Dióxido de Carbono/metabolismo , Estudos de Casos e Controles , Respiração de Cheyne-Stokes/etiologia , Respiração de Cheyne-Stokes/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Biophys J ; 110(12): 2729-2738, 2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27332131

RESUMO

Coordinated motions of close-packed multicellular systems typically generate cooperative packs, swirls, and clusters. These cooperative motions are driven by active cellular forces, but the physical nature of these forces and how they generate collective cellular motion remain poorly understood. Here, we study forces and motions in a confined epithelial monolayer and make two experimental observations: 1) the direction of local cellular motion deviates systematically from the direction of the local traction exerted by each cell upon its substrate; and 2) oscillating waves of cellular motion arise spontaneously. Based on these observations, we propose a theory that connects forces and motions using two internal state variables, one of which generates an effective cellular polarization, and the other, through contractile forces, an effective cellular inertia. In agreement with theoretical predictions, drugs that inhibit contractility reduce both the cellular effective elastic modulus and the frequency of oscillations. Together, theory and experiment provide evidence suggesting that collective cellular motion is driven by at least two internal variables that serve to sustain waves and to polarize local cellular traction in a direction that deviates systematically from local cellular velocity.


Assuntos
Movimento Celular/fisiologia , Polaridade Celular/fisiologia , Modelos Biológicos , Resinas Acrílicas , Animais , Butadienos/farmacologia , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Contagem de Células , Técnicas de Cultura de Células , Movimento Celular/efeitos dos fármacos , Polaridade Celular/efeitos dos fármacos , Tamanho Celular , Colágeno Tipo I/metabolismo , Cães , Módulo de Elasticidade , Inibidores Enzimáticos/farmacologia , Fator de Crescimento Epidérmico/farmacologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Células Madin Darby de Rim Canino , Microscopia de Fluorescência , Nitrilas/farmacologia , Periodicidade , Propriedades de Superfície
17.
Nat Mater ; 14(10): 1040-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26237129

RESUMO

From coffee beans flowing in a chute to cells remodelling in a living tissue, a wide variety of close-packed collective systems-both inert and living-have the potential to jam. The collective can sometimes flow like a fluid or jam and rigidify like a solid. The unjammed-to-jammed transition remains poorly understood, however, and structural properties characterizing these phases remain unknown. Using primary human bronchial epithelial cells, we show that the jamming transition in asthma is linked to cell shape, thus establishing in that system a structural criterion for cell jamming. Surprisingly, the collapse of critical scaling predicts a counter-intuitive relationship between jamming, cell shape and cell-cell adhesive stresses that is borne out by direct experimental observations. Cell shape thus provides a rigorous structural signature for classification and investigation of bronchial epithelial layer jamming in asthma, and potentially in any process in disease or development in which epithelial dynamics play a prominent role.


Assuntos
Asma/fisiopatologia , Brônquios/fisiopatologia , Forma Celular , Epitélio/patologia , Adesão Celular , Simulação por Computador , Células Epiteliais/citologia , Humanos , Modelos Biológicos , Software , Estresse Mecânico
18.
Soft Matter ; 12(41): 8506-8511, 2016 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-27722665

RESUMO

The cytoskeleton (CSK) is a tensed fiber framework that supports, shapes and stabilizes the cell. The CSK is in a constant state of remodeling, moreover, which is an active non-equilibrium thermodynamic process. We report here that cytoskeletal remodeling involves reconfigurations that are not only sudden but also are transmitted to great distances within the cell in a fashion reminiscent of quakes in the Earth's crust. Remarkably, these events in the cell conform both qualitatively and quantitatively to empirical laws typical of earthquakes, including hierarchical fault structures, cumulative energy distributions following the Gutenberg-Richter law, and rate of after-shocks following Omori's law. While it is well-established that remodeling and stabilization of the cytoskeleton are non-equilibrium process, these new unanticipated observations establish that these processes are also remarkably non-local and strongly cooperative.


Assuntos
Citoesqueleto/fisiologia , Miócitos de Músculo Liso/citologia , Células Cultivadas , Humanos , Termodinâmica
19.
N Engl J Med ; 367(3): 244-7, 2012 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-22808959

RESUMO

A 33-year-old woman underwent a right-sided pneumonectomy in 1995 for treatment of a lung adenocarcinoma. As expected, there was an abrupt decrease in her vital capacity, but unexpectedly, it increased during the subsequent 15 years. Serial computed tomographic (CT) scans showed progressive enlargement of the remaining left lung and an increase in tissue density. Magnetic resonance imaging (MRI) with the use of hyperpolarized helium-3 gas showed overall acinar-airway dimensions that were consistent with an increase in the alveolar number rather than the enlargement of existing alveoli, but the alveoli in the growing lung were shallower than in normal lungs. This study provides evidence that new lung growth can occur in an adult human.


Assuntos
Pulmão/fisiologia , Pneumonectomia , Regeneração , Adenocarcinoma/cirurgia , Adenocarcinoma de Pulmão , Adulto , Feminino , Humanos , Imageamento Tridimensional , Pulmão/diagnóstico por imagem , Pulmão/patologia , Neoplasias Pulmonares/cirurgia , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X
20.
Eur Respir J ; 45(2): 408-18, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25323235

RESUMO

Elevated loop gain, consequent to hypersensitive ventilatory control, is a primary nonanatomical cause of obstructive sleep apnoea (OSA) but it is not possible to quantify this in the clinic. Here we provide a novel method to estimate loop gain in OSA patients using routine clinical polysomnography alone. We use the concept that spontaneous ventilatory fluctuations due to apnoeas/hypopnoeas (disturbance) result in opposing changes in ventilatory drive (response) as determined by loop gain (response/disturbance). Fitting a simple ventilatory control model (including chemical and arousal contributions to ventilatory drive) to the ventilatory pattern of OSA reveals the underlying loop gain. Following mathematical-model validation, we critically tested our method in patients with OSA by comparison with a standard (continuous positive airway pressure (CPAP) drop method), and by assessing its ability to detect the known reduction in loop gain with oxygen and acetazolamide. Our method quantified loop gain from baseline polysomnography (correlation versus CPAP-estimated loop gain: n=28; r=0.63, p<0.001), detected the known reduction in loop gain with oxygen (n=11; mean±sem change in loop gain (ΔLG) -0.23±0.08, p=0.02) and acetazolamide (n=11; ΔLG -0.20±0.06, p=0.005), and predicted the OSA response to loop gain-lowering therapy. We validated a means to quantify the ventilatory control contribution to OSA pathogenesis using clinical polysomnography, enabling identification of likely responders to therapies targeting ventilatory control.


Assuntos
Polissonografia , Respiração , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/fisiopatologia , Acetazolamida , Adulto , Simulação por Computador , Pressão Positiva Contínua nas Vias Aéreas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Oscilometria , Oxigênio , Cooperação do Paciente , Fenótipo , Estudos Retrospectivos , Sono
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