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1.
Qual Life Res ; 29(3): 825-831, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31782017

RESUMO

PURPOSE: To examine the responsiveness and minimal clinically important difference (MCID) of the TNO-AZL (Netherlands Organization for Applied Scientific Research Academic Medical Centre) Preschool Children Quality of Life (TAPQOL) in children with cerebral palsy (CP). METHODS: Ninety-seven children with CP (60 males, 37 females; aged 1-6 years) and their caregivers were recruited from the rehabilitation programs of Chang Gung Memorial Hospital in Taiwan for this 6-month longitudinal follow-up study. The Functional Independence Measure for Children (WeeFIM) and TAPQOL outcomes were measured at baseline and at a 6-month follow-up. Responsiveness was examined using the standardized response mean (SRM). The distribution-based and anchor-based MCID were determined. The TAPQOL outcomes include physical functioning (PF), social functioning (SF), cognitive functioning (CF), and emotional functioning (EF) domains. RESULTS: The responsiveness of the TAPQOL for all of TAPQOL domains was marked (SRM = 1.12-1.54). The anchor-based MCIDs of TAPQOL for PF, SF, CF, EF, and total domains were 1.25, 3.28, 2.93, 2.25, and 1.73, respectively, which were similar to the distribution-based MCID values of TAPQOL, except in the PF domain. The distribution-based MCIDs of TAPQOL in various domains were 2.85-3.73 when effect size (ES) was 0.2, 7.13-9.32 when ES was 0.5, and 11.40-14.91 when ES was 0.8. CONCLUSIONS: TAPQOL is markedly responsive to detect change in children with CP. The caregivers perceived the minimally important change in HRQOL of their children at a relatively low treatment efficacy. Researchers and clinicians can utilize TAPQOL data to determine whether changes in TAPQOL scores indicate clinically meaningful effects post-treatment and at the follow-up.


Assuntos
Paralisia Cerebral/psicologia , Cognição/fisiologia , Diferença Mínima Clinicamente Importante , Desempenho Físico Funcional , Qualidade de Vida/psicologia , Cuidadores , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Países Baixos , Taiwan , Resultado do Tratamento
2.
Acta Anaesthesiol Scand ; 62(6): 756-764, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29504128

RESUMO

BACKGROUND: Acute normovolemic hemodilution (ANH) is considered safe and effective in decreasing perioperative transfusion in paediatric populations undergoing high blood-loss surgeries. We determined the association between ANH and the intraoperative use of allogeneic blood products in paediatric cardiac surgery patients. METHODS: This is a single-centre retrospective cohort study including paediatric patients between 0 and 36 months of age undergoing surgical repair or palliation of their cardiac defect with the use of cardiopulmonary bypass between November 2013 and November 2014. Our primary endpoint was the volume per kilogram of body weight of any blood product administered. Secondary endpoints were postoperative bleeding, coagulation profile, creatinine, vasoactive support, duration of mechanical ventilation, and hospital stay. RESULTS: In all, 50 patients met eligibility criteria and were included. Of those, seven were exposed to ANH and while 43 patients were treated according to usual care. Baseline characteristics were similar in both groups. After adjustment for baseline characteristics including age, American Society of Anaesthesiologists (ASA) classification, and Risk Adjusted Congenital Heart Surgery score, ANH was associated with reduced administration of allogenic blood products, with the mean difference between groups of 57.5 ml/kg (95% CI: 34.8, 80.2). The ANH group had lower blood losses at 6 and 24 h postoperatively. There were no differences in the duration of ICU or hospital stay. CONCLUSION: We found a reduction in the administration of blood products and lower postoperative blood losses associated with the use of ANH in paediatric cardiac surgery patients. The data suggest that ANH might be beneficial in reducing perioperative morbidity in this patient population.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Hemodiluição , Transfusão de Sangue , Ponte Cardiopulmonar , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva , Tempo de Internação , Masculino , Hemorragia Pós-Operatória/prevenção & controle , Estudos Retrospectivos
3.
IEEE Comput Graph Appl ; 44(2): 100-109, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38015709

RESUMO

Neural radiance field (NeRF) has emerged as a versatile scene representation. However, it is still unintuitive to edit a pretrained NeRF because the network parameters and the scene appearance are often not explicitly associated. In this article, we introduce the first framework that enables users to retouch undesired regions in a pretrained NeRF scene without accessing any training data and category-specific data prior. The user first draws a free-form mask to specify a region containing the unwanted objects over an arbitrary rendered view from the pretrained NeRF. Our framework transfers the user-drawn mask to other rendered views and estimates guiding color and depth images within transferred masked regions. Next, we formulate an optimization problem that jointly inpaints the image content in all masked regions by updating NeRF's parameters. We demonstrate our framework on diverse scenes and show it obtained visually plausible and structurally consistent results using less user manual efforts.

4.
Int J Oral Maxillofac Implants ; 0(0): 1-23, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38717348

RESUMO

PURPOSE: This experimental study investigated how well implant stability quotient (ISQ) represents resonance frequency. Benchtop experiments on standardized samples, mimicking a premolar section of a mandible, were conducted to correlate an ISQ value and a resonance frequency to synthetic bone density and an incremental insertion torque. A frequency spectrum analysis was performed to check the validity of the resonance frequency analysis (RFA). MATERIALS AND METHODS: Branemark Mk III implants with dimensions ∅4 Å~ 11.5 mm were placed in Sawbones test models of five different densities (40, 30, 40/20, 20, 15 PCF). An incremental insertion torque was recorded during implant placement. To perform stability measurements, the test models were clamped partially in a vise (unclamped volume 10 Å~ 20 Å~ 34 mm). A MultiPeg was attached onto the implants, and a Penguin RFA measured ISQ. Simultaneously, motion of the MultiPeg was monitored via a laser Doppler vibrometer and processed by a spectrum analyzer to obtain the resonance frequency. Tightness of the clamp was adjusted to vary the resonance frequency. A statistical analysis produced a linear correlation coefficient 𝑅 among the measured ISQ, resonance frequency, and incremental insertion torque. RESULTS: The resonance frequency had high correlation to the incremental insertion torque (𝑅 = 0.978), confirming the validity of using RFA for this study. Measured ISQ data were scattered and had low correlation to the resonance frequency (𝑅 = 0.214) as well as the incremental insertion torque (𝑅 = -0.386). The spectrum analysis revealed simultaneous presence of multiple resonance frequencies. CONCLUSIONS: For the designed benchtop tests, resonance frequency does indicate implant stability in view of Sawbones density and incremental insertion torque. ISQ measurements, however, do not correlate well to the resonance frequency, and may not reflect the stability when multiple resonance frequencies are present simultaneously.

5.
Dev Med Child Neurol ; 55(8): 745-50, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23590429

RESUMO

AIM: The aim of this study was to assess the validity, responsiveness, and clinimetric properties of the Spinal Alignment and Range of Motion Measure (SAROMM) in children with cerebral palsy (CP). METHOD: Sixty-two children with CP (40 males, 22 females) with a median age of 3 years and 11 months (range 1-6y) and their caregivers participated in this study. Among the children, 56 had spastic CP while six had non-spastic CP; 53 had bilateral CP, while nine had unilateral limb involvement. Thirty-three children were classified as Gross Motor Function Classification System (GMFCS) levels I to III and 23 as levels IV or V. Fifty-six children (90%) received regular rehabilitation by means of regular physical or occupational therapy (50% once or twice per week and 40% more than two times per week) and six children (10%) received irregular rehabilitation (less than once a week). Construct validity was determined by assessing the strength of the correlation between the spinal alignment SAROMM (SAROMM-SA), the range of motion SAROMM (SAROMM-ROM), and the total SAROMM (SAROMM-total), and construct measures, including the 66-item Gross Motor Function Measure (GMFM-66) and Functional Independence Measures for Children (WeeFIM), at baseline and at 6-months follow-up. Responsiveness was examined using effect size. Minimal detectable change (MDC) at the 90% confidence level (MDC90) and minimal clinically important difference (MCID) were analysed. RESULTS: The SAROMM with the GMFM-66 and WeeFIM had fair to good construct validity. The effect size values of all SAROMM scales were 0.24 to 0.48. The MDC90 values and MCID range were 1.43 and 0.47 to 1.67 for the SAROMM-SA, 3.12 and 3.68 to 4.07 for the SAROMM-ROM, and 3.22 and 4.53 to 4.62 for the SAROMM-total. INTERPRETATION: The clinimetric properties of the SAROMM allow clinicians to determine whether a change in SAROMM score represents a clinically meaningful change.


Assuntos
Paralisia Cerebral/diagnóstico , Testes Neuropsicológicos/normas , Psicometria/instrumentação , Amplitude de Movimento Articular/fisiologia , Doenças da Coluna Vertebral/diagnóstico , Paralisia Cerebral/fisiopatologia , Paralisia Cerebral/reabilitação , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Destreza Motora/fisiologia , Sensibilidade e Especificidade , Índice de Gravidade de Doença
6.
IEEE Comput Graph Appl ; 42(4): 72-79, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34559641

RESUMO

This article presents a data-driven approach for beautifying freehand sketches. Our key premise is that the artist-drawn vector can be used to sketch visually appealing shapes, such as local shapes with a clean appearance and better global visual properties (e.g., symmetry). However, these merits may not apply to all object categories. In this article, we use a neural network to represent local and global merits across different object categories to design our beautification method. First, we match sample points between input sketches and the collected vector shapes using the extracted feature representations. Then, we design an optimization problem to ensure resemblance between the deformed sketch and vector shape in the representation space while preserving the semantic meaning and style of the original sketch. Finally, we demonstrate our method on sketches across different shape categories.


Assuntos
Algoritmos , Arte , Redes Neurais de Computação , Semântica
7.
IEEE Trans Vis Comput Graph ; 28(12): 4211-4224, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34057894

RESUMO

This article presents a novel deep learning-based approach for automatically vectorizing and synthesizing the clipart of man-made objects. Given a raster clipart image and its corresponding object category (e.g., airplanes), the proposed method sequentially generates new layers, each of which is composed of a new closed path filled with a single color. The final result is obtained by compositing all layers together into a vector clipart image that falls into the target category. The proposed approach is based on an iterative generative model that (i) decides whether to continue synthesizing a new layer and (ii) determines the geometry and appearance of the new layer. We formulated a joint loss function for training our generative model, including the shape similarity, symmetry, and local curve smoothness losses, as well as vector graphics rendering accuracy loss for synthesizing clipart recognizable by humans. We also introduced a collection of man-made object clipart, ClipNet, which is composed of closed-path layers, and two designed preprocessing tasks to clean up and enrich the original raw clipart. To validate the proposed approach, we conducted several experiments and demonstrated its ability to vectorize and synthesize various clipart categories. We envision that our generative model can facilitate efficient and intuitive clipart designs for novice users and graphic designers.

8.
Eur J Cardiovasc Prev Rehabil ; 18(4): 561-73, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21450629

RESUMO

AIM: To estimate the national prevalence, mortality risk and population mortality burden of metabolic syndrome, and compare the values with those of its individual components. METHODS AND RESULTS: A total of 486,341 apparently healthy adults who went through a screening programme in Taiwan were recruited from 1994 onwards. As of 2007, 15,268 deaths had occurred at least one year after the examination. Six definitions of metabolic syndrome were used. Components of metabolic syndrome include obesity, hypertension, hyperglycaemia, dyslipidaemia and albuminuria. Hazard ratios (HRs) were calculated using the Cox proportional hazard model. The population mortality burden considered both national prevalence and HRs. The national prevalence of metabolic syndrome defined by the Adult Treatment Panel (ATP) III was 16.3%, the HR for all causes was 1.36 (95%, CI 1.31-1.41) and the HR for cardiovascular disease (CVD) was 1.63 (95%, CI 1.51-1.77). The population mortality burden of metabolic syndrome was 5.5% for all causes, in contrast to 9.0% for hypertension, 8.9% for albuminuria, 6.6% for diabetes, 3.5% for dyslipidaemia and 1.5% for obesity. For CVD it was 9.4%, lower than 10.7% for albuminuria and 25.0% for hypertension. CONCLUSION: The mortality burden of metabolic syndrome was relatively small at national level. Three of the five components of metabolic syndrome alone, namely hypertension, diabetes and albuminuria, contributed more than metabolic syndrome to all-cause mortality. Successful management of any of these three components would have achieved a greater impact on mortality than management of metabolic syndrome.


Assuntos
Doenças Cardiovasculares/mortalidade , Síndrome Metabólica/mortalidade , Adulto , Idoso , Albuminúria/mortalidade , Dislipidemias/mortalidade , Feminino , Humanos , Hiperglicemia/mortalidade , Hipertensão/mortalidade , Estimativa de Kaplan-Meier , Masculino , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade , Obesidade/mortalidade , Razão de Chances , Prevalência , Modelos de Riscos Proporcionais , Medição de Risco , Fatores de Risco , Taiwan/epidemiologia , Fatores de Tempo , Adulto Jovem
9.
Fish Physiol Biochem ; 37(4): 709-24, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21336594

RESUMO

Opposite patterns of branchial Na(+)/K(+)-ATPase (NKA) responses were found in euryhaline milkfish (Chanos chanos) and pufferfish (Tetraodon nigroviridis) upon salinity challenge. Because the electrochemical gradient established by NKA is thought to be the driving force for transcellular Cl(-) transport in fish gills, the aim of this study was to explore whether the differential patterns of NKA responses found in milkfish and pufferfish would lead to distinct distribution of Cl(-) transporters in their gill epithelial cells indicating different Cl(-) transport mechanisms. In this study, immunolocalization of various Cl(-) transport proteins, including Na(+)/K(+)/2Cl(-) cotransporter (NKCC), cystic fibrosis transmembrane conductance regulator (CFTR), anion exchanger 1 (AE1), and chloride channel 3 (ClC-3), were double stained with NKA, the basolateral marker of branchial mitochondrion-rich cells (MRCs), to reveal the localization of these transporter proteins in gill MRC of FW- or SW-acclimated milkfish and pufferfish. Confocal microscopic observations showed that the localization of these transport proteins in the gill MRCs of the two studied species were similar. However, the number of gill NKA-immunoreactive (IR) cells in milkfish and pufferfish exhibited to vary with environmental salinities. An increase in the number of NKA-IR cells should lead to the elevation of NKA activity in FW milkfish and SW pufferfish. Taken together, the opposite branchial NKA responses observed in milkfish and pufferfish upon salinity challenge could be attributed to alterations in the number of NKA-IR cells. Furthermore, the localization of these Cl(-) transporters in gill MRCs of the two studied species was identical. It depicted the two studied euryhaline species possess the similar Cl(-) transport mechanisms in gills.


Assuntos
Canais de Cloreto/metabolismo , Brânquias/enzimologia , Salinidade , ATPase Trocadora de Sódio-Potássio/metabolismo , Tetraodontiformes/metabolismo , Aclimatação , Animais , Imunofluorescência
10.
Int J Oral Maxillofac Implants ; 36(2): e7-e21, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33909715

RESUMO

PURPOSE: This numerical study examined the efficacy and challenges of using resonance frequency analysis to identify the stability of implants placed in mandibles. The study also examined the feasibility of using angular stiffness as an alternative index to quantify dental implant stability in mandibles. MATERIALS AND METHODS: A finite element model consisting of a mandible, an implant, an abutment, and a bonding layer (between the implant and the mandible) was created in commercially available software ANSYS. The level of osseointegration was modeled by varying the stiffness of the bonding layer. Three sets of boundary conditions were imposed on the mandible: fixed, rotationally free, and rotationally restrained. Three implant locations were studied: central, premolar, and molar positions. An alternative abutment mimicking SmartPeg and eight different implant lengths were also included. A modal analysis and a static analysis were conducted to calculate resonance frequencies and angular stiffness, respectively. RESULTS: Two types of vibration modes were found. One was jawbone modes, for which the mandible deformed significantly but not the bonding layer. Resonance frequencies of the jawbone modes were not sensitive to the level of osseointegration. The other was implant modes, for which the bonding layer deformed significantly but not the mandible. Among multiple implant modes obtained, only one was trackable as the level of osseointegration increased. The resonance frequency of the trackable implant mode was very sensitive to the implant location as well as boundary conditions, but not as much to the level of osseointegration. In contrast, angular stiffness was sensitive to the level of osseointegration but not as much to boundary conditions. CONCLUSION: The efficacy of using resonance frequency analysis to quantify the stability of a dental implant is questionable. Its high sensitivity to implant locations and boundary conditions as well as its low sensitivity to the level of osseointegration cause huge uncertainties in correlating measured resonance frequencies to implant stability. Angular stiffness is a much more reliable indicator because of its high sensitivity to the level of osseointegration and low sensitivity to boundary conditions.


Assuntos
Implantes Dentários , Implantação Dentária Endóssea , Planejamento de Prótese Dentária , Retenção em Prótese Dentária , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Osseointegração , Análise de Frequência de Ressonância , Vibração
11.
J Sci Med Sport ; 24(10): 1026-1031, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32571627

RESUMO

OBJECTIVES: Develop a method to examine the effects of component geometry and force-deflection on the release process of Tech/Pin alpine touring (AT) ski boots and bindings. DESIGN AND METHODS: For seven AT boots, we measured the critical geometric dimensions of the metal inserts at the toe region of the boots. Binding geometry (including the pins and rocker arms) and the force-angular deflection curves of typical AT bindings were measured. A kinematic model was derived to predict the contact force between the metal inserts of the AT boots and the pins of the AT bindings, dependent on angular displacement of the binding rocker arms. By combining the kinematic model, the force-angular deflection curves, and moment equilibrium, we determined the force and binding rotation angle needed to release the AT boot in a direction normal to the ski. RESULTS: The metal AT boot insert geometry and AT binding pin geometry and dimensions can affect significantly the contact states and kinematics of release. Two load-deflection curves of similar peak loads can result in significantly different maximal forces and angles to release the binding, even when the geometry and dimensions of the binding pins and boot inserts remain unchanged. CONCLUSIONS: The geometry and dimensions of the binding (pins and rocker arm) and the boot inserts define the kinematics of the binding release. The model can be used to test the effects of varying parameters on the release and retention characteristics of Tech/Pin boot-binding systems to optimize the release and retention characteristics.


Assuntos
Desenho de Equipamento , Teste de Materiais , Esqui , Equipamentos Esportivos , Fenômenos Biomecânicos , Humanos
12.
Percept Mot Skills ; 110(2): 411-28, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20499552

RESUMO

This study explored the effects of color combinations and polarity on user preferences and EEG responses using an icon design for a visual display terminal. 72 college students (M=24.5 yr., SD=2.3 yr.) were tested. The seven color combinations of top 16% with rating scores (5-point scale) over 3.60 almost always included black or white as a target or background, including white-on-black, red-on-black, yellow-on-black, blue-on-white, and black-on-white; the other two preferred color combinations were yellow-on-blue and blue-on-yellow. The eight color combinations of the bottom 16% with rating scores under 2.38 almost always included green, turquoise, or purple as a target or background. Negative image polarity (higher luminance color image shown on a lower luminance color background) was preferred over positive image polarity (lower luminance color image shown on a higher luminance color background) by the subjects. The theta and alpha band power in the right hemisphere were greater than those in the left hemisphere during the experiment. There seemed to be no linear correlation between the rating scores of subjective preferences and brain wave power of theta and alpha bands, so the possibility of using brain wave power to measure subjective preference is questionable.


Assuntos
Comportamento de Escolha/fisiologia , Percepção de Cores/fisiologia , Terminais de Computador , Eletroencefalografia , Reconhecimento Visual de Modelos/fisiologia , Processamento de Sinais Assistido por Computador , Adulto , Ritmo alfa , Córtex Cerebral/fisiologia , Sensibilidades de Contraste , Dominância Cerebral/fisiologia , Feminino , Humanos , Masculino , Ritmo Teta , Interface Usuário-Computador , Adulto Jovem
13.
Percept Mot Skills ; 127(6): 985-1014, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32611227

RESUMO

In this study we investigated the effects of advance information on task switching in young and old adults, using two forms of advance information (memory-based and cue-based) and a no advance information task. We compared 19 healthy young and 19 healthy older adults in terms of their behavioral performance and neural correlates under these three task-switching paradigms. We observed a significant difference in mixing cost between the two age groups. There was no switch cost group difference on the memory-based and cue-based tasks, but older adults showed a larger switch cost than younger adults on the no advance information task. On evoked potential measures, there was no group effect in P3 cue-locked positivity; but there was, a frontal shift of the target-locked P3, indexed as reactive control, among older adults. We observed an increased target-locked P3 in the no-information paradigm compared with the cue-based and memory-based paradigms in both groups. Task cue facilitated advance preparation and proactive control under the cue-based paradigm in both groups. Age-related decline and difficulty in control processes required for task goal maintenance were apparent among the older adults.


Assuntos
Cognição/fisiologia , Disfunção Cognitiva/psicologia , Conhecimento , Memória/fisiologia , Tempo de Reação/fisiologia , Adolescente , Fatores Etários , Idoso , Encéfalo/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Sinais (Psicologia) , Eletroencefalografia , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
J Neurotrauma ; 37(1): 115-124, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31317830

RESUMO

Individuals with a mild traumatic brain injury (mTBI) often have executive control deficits; however, the underlying neural mechanisms of such deficits are yet to be clarified. Inhibitory control and cognitive monitoring are two fundamental aspects of executive control processes. This study investigated the executive control of mTBI by using the Stop-signal task. Eighteen adults with mTBI and 18 age-, sex-, and education level-matched controls were recruited. Behavioral performance and event-related potential correlates of response inhibition and error processing were compared between groups. The mTBI group tended to have a lower probability of inhibition and a longer stop signal reaction time. N1 amplitude was greater on successful trials. Also on successful trials, N2 and P3 peaked earlier than on failed trials. The N2 amplitude of the mTBI group tended to be smaller than that of the controls. The control group had larger P3 amplitude on successful trials than on failed trials, whereas the mTBI group exhibited no P3 amplitudes difference between the two trial types. In addition, the mTBI group showed significantly longer error positivity latency than did the controls. These results suggest that inhibitory control and error processing were inefficient in the mTB group even more than three months after injury. Electrophysiological markers of cognitive dysfunction can be used as a sensitive tool for determining executive control after mTBI.


Assuntos
Concussão Encefálica/fisiopatologia , Disfunção Cognitiva/diagnóstico , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Síndrome Pós-Concussão/diagnóstico , Adulto , Concussão Encefálica/complicações , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/fisiopatologia , Eletroencefalografia , Eletroculografia , Feminino , Humanos , Inibição Psicológica , Masculino , Pessoa de Meia-Idade , Síndrome Pós-Concussão/fisiopatologia , Tempo de Reação/fisiologia , Adulto Jovem
15.
J Cell Biol ; 102(3): 795-802, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3949879

RESUMO

Ascorbic acid in soluble extracts of neural tissue can account for the increase in surface acetylcholine receptors (AChR's) seen on L5 myogenic cells treated with crude brain extract (Knaack, D., and T. R. Podleski, 1985, Proc. Natl. Acad. Sci. USA., 82:575-579). The present study further elucidates the nature of the response of L5 cells to ascorbic acid. Light autoradiography showed that ascorbic acid treatment affects both the number and distribution of surface AChR's. Ascorbic acid, like crude brain extracts, caused a three- to fourfold increase in average AChR site density. However, the number of AChR clusters induced by ascorbic acid was only one-fifth that observed with crude brain extract. The rate constant for degradation of AChR in ascorbic acid-treated cells of 0.037 +/- 0.006 h-1 (t1/2 = 19 h) was not significantly different from that in untreated controls of 0.050 +/- 0.001 h-1 (t1/2 = 14 h). The increase in AChR site density is primarily due to a 2.8-fold increase in the average rate of AChR incorporation. Ascorbic acid also stimulates thymidine incorporation and increases the total number of nuclei per culture. However, cellular proliferation is not responsible for the increase in AChR's since 10 microM cytosine arabinofuranoside blocks the mitogenic effect without affecting the AChR increase. The specificity of ascorbic acid on AChR expression was established by showing that (a) ascorbic acid produced only a slight increase in total protein, which can be accounted for by the mitogenic effect, and (b) the normal increase seen in creatine kinase activity during muscle differentiation was not altered by the addition of ascorbic acid. We conclude that the action of ascorbic acid on AChR number cannot be explained by changes in cell growth, survival, differentiation, or protein synthesis. Therefore, in addition to a minor stimulation of AChR clustering, ascorbic acid specifically affects some aspect of the AChR biosynthetic pathway.


Assuntos
Ácido Ascórbico/farmacologia , Músculos/análise , Receptores Colinérgicos/análise , Animais , Química Encefálica , Bovinos , Diferenciação Celular/efeitos dos fármacos , Divisão Celular , Células Cultivadas , Creatina Quinase/análise , Músculos/citologia , Músculos/efeitos dos fármacos , Receptores Colinérgicos/biossíntese
16.
Int J Oral Maxillofac Implants ; 34(3): 595­603, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30807625

RESUMO

PURPOSE: This study assessed the ability of resonance frequency measurements to differentiate the stability of implants with different lengths and diameters, and in different densities of bone. Another objective was to identify an alternative parameter capable of quantifying dental implant stability, thus facilitating greater sensitivity for efficacious detection of compromised or failing implants. MATERIALS AND METHODS: Implants of two different diameters (4 and 5 mm) and six different lengths were individually placed in synthetic bone blocks of three different densities (15, 40/20, and 40 pounds per cubic foot) in combination with two different abutments (short and tall) to evaluate their stability. Resonance frequency measurements were obtained via Osstell ISQ and experimental modal analysis (EMA). The resonance frequency measurements were further confirmed via finite element analysis (FEA) using commercially available software ANSYS. RESULTS: Resonance frequencies measured via Osstell ISQ and EMA did not change with respect to the length of the implants. The FEA also confirmed the measured results. FEA simulations further indicated that angular stiffness at the neck of the implant (ie, the base of the abutment) varied considerably with respect to the implant length and diameter. Moreover, the calculated angular stiffness was independent of the type of abutment used. CONCLUSION: The results obtained from resonance frequency analyses did not accurately represent dental implant stability. Changes to implant length and diameter did not affect resonance frequencies. In contrast, angular stiffness at the neck of the implant represented a superior index for quantifying dental implant stability. It not only successfully differentiated stability of implants of both varying lengths and diameters, but also produced quantitative data that was independent of the type of abutments used.


Assuntos
Implantes Dentários , Implantação Dentária Endóssea , Planejamento de Prótese Dentária , Retenção em Prótese Dentária , Osseointegração , Análise de Frequência de Ressonância , Vibração
17.
Eur J Phys Rehabil Med ; 55(6): 754-760, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30868834

RESUMO

BACKGROUND: Spasticity is a major problem in patients with stroke and influences their activities of daily living, participation, and quality of life. The Modified Ashworth Scale is widely used to assess spasticity. However, the responsiveness and minimal clinically important differences of the Modified Ashworth Scale in patients with stroke have not been explored. AIM: This study aims to examine the responsiveness and minimal clinically important differences of the Modified Ashworth Scale in patients with stroke. DESIGN: Longitudinal six-month follow-up study. SETTING: Rehabilitation wards of a tertiary hospital. POPULATION: One-hundred and fifteen patients with stroke were recruited. METHODS: All patients underwent the assessment of Modified Ashworth Scale for the upper extremity (flexors of the elbow, wrist, and fingers) and the lower extremity (hip adductor, knee flexor, and ankle plantar flexor) at baseline and 6-month follow-up. The average Modified Ashworth Scale scores of the upper and lower extremity muscles were obtained for analysis. Responsiveness of the Modified Ashworth Scale was determined using standardized mean response, and the minimal clinically important differences were determined using a distribution-based approach with Effect Sizes of 0.5 and 0.8 standard deviations. RESULTS: The responsiveness of the Modified Ashworth Scale in the upper and lower extremity muscles was marked (standardized response mean = 0.89-1.09). The minimal clinically important differences of the average Modified Ashworth Scale of Effect Sizes 0.5 and 0.8 standard deviations for the upper extremity muscles were 0.48 and 0.76, respectively, while those for the lower extremity muscles were 0.45 and 0.73, respectively. CONCLUSIONS: The Modified Ashworth Scale was markedly responsive in detecting the changes in muscle tone in patients with stroke. The minimal clinically important differences of the Modified Ashworth Scale reported in this study can be used by researchers and clinicians in determining whether the observed changes are clinically meaningful post-treatment or at follow-up. CLINICAL REHABILITATION IMPACT: The minimal clinically important differences of the Modified Ashworth Scale reported in this study will enable clinicians and researchers in determining whether changes in the muscle tone are true and clinically meaningful, and can be used as a reference for clinical decision-making.


Assuntos
Espasticidade Muscular/diagnóstico , Espasticidade Muscular/fisiopatologia , Tono Muscular , Acidente Vascular Cerebral/fisiopatologia , Atividades Cotidianas , Adulto , Idoso , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Diferença Mínima Clinicamente Importante , Espasticidade Muscular/etiologia , Qualidade de Vida , Acidente Vascular Cerebral/complicações , Adulto Jovem
18.
Maturitas ; 114: 27-33, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29907243

RESUMO

OBJECTIVE: To assess the risk of stroke (and subtypes of stroke) in women after elective bilateral salpingo-oophorectomy at hysterectomy for benign diseases. STUDY DESIGN: We conducted a nationwide population-based, retrospective cohort study using claims data from Taiwan's National Health Insurance program between 1997 and 2013. Women aged 20 years or more who underwent bilateral salpingo-oophorectomy at hysterectomy for benign diseases (n = 1083) were compared with women who did not undergo bilateral salpingo-oophorectomy at hysterectomy for benign diseases (n = 3903). The follow-up period ranged from 10 to 16 years. Age-adjusted (or unadjusted) and multivariate Cox proportional hazards regression models were used to estimate the risk of stroke between the two groups. MAIN OUTCOME MEASURES: A diagnosis of stroke (and subtypes of stroke). RESULTS: We did not find a significant association between bilateral salpingo-oophorectomy and the risk of incident stroke (or subtypes of stroke) over an average follow-up of 13 years. Among women aged 50 years or more who used estrogen therapy, the risk of developing stroke was 64% lower in those who had undergone bilateral salpingo-oophorectomy (hazard ratio, 0.36; 95% confidence interval, 0.16-0.79) than in those who had undergone hysterectomy only. CONCLUSION: This study suggests that the use of estrogen after bilateral salpingo-oophorectomy at hysterectomy for benign diseases reduces the risk of stroke in women aged 50 years or more.


Assuntos
Histerectomia/efeitos adversos , Salpingo-Ooforectomia/efeitos adversos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Feminino , Seguimentos , Humanos , Incidência , Pessoa de Meia-Idade , Estudos Retrospectivos , Risco , Taiwan
19.
Bioinspir Biomim ; 12(4): 046001, 2017 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-28474606

RESUMO

Maneuvering in both natural and artificial miniature flying systems is assumed to be dominated by aerodynamic phenomena. To explore this, we develop a flapping wing model integrating aero and inertial dynamics. The model is applied to an elliptical wing similar to the forewing of the Hawkmoth Manduca sexta and realistic kinematics are prescribed. We scrutinize the stroke deviation phase, as it relates to firing latency in airborne insect steering muscles which has been correlated to various aerial maneuvers. We show that the average resultant force production acting on the body largely arises from wing pitch and roll and is insensitive to the phase and amplitude of stroke deviation. Inclusion of stroke deviation can generate significant averaged aerodynamic torques at steady-state and adjustment of its phase can facilitate body attitude control. Moreover, averaged wing angular momentum varies with stroke deviation phase, implying a non-zero impulse during a time-dependent phase shift. Simulations show wing inertial and aerodynamic impulses are of similar magnitude during short transients whereas aerodynamic impulses dominate during longer transients. Additionally, inertial effects become less significant for smaller flying insects. Body yaw rates arising from these impulses are consistent with biologically measured values. Thus, we conclude (1) modest changes in stroke deviation can significantly affect steering and (2) both aerodynamic and inertial torques are critical to maneuverability, the latter of which has not widely been considered. Therefore, the addition of a control actuator modulating stroke deviation may decouple lift/thrust production from steering mechanisms in flapping wing micro aerial vehicles and increase vehicle dexterity through inertial trajectory shaping.


Assuntos
Biomimética , Voo Animal/fisiologia , Manduca/fisiologia , Asas de Animais/fisiologia , Algoritmos , Animais , Aviação , Fenômenos Biomecânicos , Manduca/anatomia & histologia , Modelos Biológicos , Músculo Esquelético/fisiologia , Torque , Asas de Animais/anatomia & histologia
20.
Percept Mot Skills ; 124(1): 145-165, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27932536

RESUMO

The study investigated whether children with autism spectrum disorders (ASD) showed atypical patterns of brain specialization for face processing, whether the response to familiar and unfamiliar faces, facial features, and objects were different from typically developing children. Event-related potentials were recorded in 5- to 8-year-old children (12 children with ASD, 12 typically developing children) using passive viewing paradigm. The fastest P1 latencies to faces and the largest P1 amplitudes to objects were observed in both participant groups. Both groups exhibited larger N170 response to faces and eyes, F(3, 66) = 46.94, p < .0001). However, earlier P1 and N170 latencies were found on left hemisphere in children with ASD, respectively, F(1, 83) = 4.32, p = .04; F(1, 83) = 6.73, p = .01, indicating an atypical face processing pattern. All children showed a significant effect of familiarity for objects and mouths, F(1, 71) = 33.97, p < .0001; F(1, 71 = 15.94, p = .0002. Children with ASD revealed smaller negative central to faces relative to typically developing children. Face processing abnormalities revealed in children with ASD very likely exist.

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