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2.
Materials (Basel) ; 17(1)2023 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-38204024

RESUMEN

This review introduces an innovative technology termed "Micro-Extrusion Foaming (MEF)", which amalgamates the merits of physical foaming and 3D printing. It presents a groundbreaking approach to producing porous polymer fibers and parts. Conventional methods for creating porous materials often encounter obstacles such as the extensive use of organic solvents, intricate processing, and suboptimal production efficiency. The MEF technique surmounts these challenges by initially saturating a polymer filament with compressed CO2 or N2, followed by cell nucleation and growth during the molten extrusion process. This technology offers manifold advantages, encompassing an adjustable pore size and porosity, environmental friendliness, high processing efficiency, and compatibility with diverse polymer materials. The review meticulously elucidates the principles and fabrication process integral to MEF, encompassing the creation of porous fibers through the elongational behavior of foamed melts and the generation of porous parts through the stacking of foamed melts. Furthermore, the review explores the varied applications of this technology across diverse fields and imparts insights for future directions and challenges. These include augmenting material performance, refining fabrication processes, and broadening the scope of applications. MEF technology holds immense potential in the realm of porous material preparation, heralding noteworthy advancements and innovations in manufacturing and materials science.

3.
Sci Transl Med ; 14(639): eabm0899, 2022 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-35230146

RESUMEN

A major challenge to end the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is to develop a broadly protective vaccine that elicits long-term immunity. As the key immunogen, the viral surface spike (S) protein is frequently mutated, and conserved epitopes are shielded by glycans. Here, we revealed that S protein glycosylation has site-differential effects on viral infectivity. We found that S protein generated by lung epithelial cells has glycoforms associated with increased infectivity. Compared to the fully glycosylated S protein, immunization of S protein with N-glycans trimmed to the mono-GlcNAc-decorated state (SMG) elicited stronger immune responses and better protection for human angiotensin-converting enzyme 2 (hACE2) transgenic mice against variants of concern (VOCs). In addition, a broadly neutralizing monoclonal antibody was identified from SMG-immunized mice that could neutralize wild-type SARS-CoV-2 and VOCs with subpicomolar potency. Together, these results demonstrate that removal of glycan shields to better expose the conserved sequences has the potential to be an effective and simple approach for developing a broadly protective SARS-CoV-2 vaccine.


Asunto(s)
Vacunas contra la COVID-19 , Polisacáridos , Glicoproteína de la Espiga del Coronavirus , Animales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/prevención & control , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/metabolismo , Humanos , Ratones , Modelos Animales , SARS-CoV-2 , Vacunación
4.
Chem Biodivers ; 15(10): e1800235, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29996001

RESUMEN

Angelica pubescens, a plant of the family Umbelliferae, has been widely used as traditional Chinese medicine for the treatment of many diseases. However, there has been minimal modern research focused on the pharmacological activity of oils extracted from Angelica pubescens, in particular, the potential anti-photoaging effects. Therefore, in the present study, we analyzed the chemical composition of Angelica pubescens oil (AO) and evaluated its bioactivity against photoaging in ultraviolet (UV) -B radiation-induced hairless mice. Overall, we identified and analyzed 93 compounds from the AO by gas chromatography-mass spectrometry (GC/MS). The top ten compounds were as follows: osthole (44.608%), glutaric acid hexadecyl pent-4-en-1-yl ester (5.758%), α-bisabolol (3.795%), eugenol (3.637%), (Z)-docos-13-enamide (3.286%), (3S,3aR)-3-butyl-3a,4,5,6-tetrahydro-3H-2-benzofuran-1-one (3.043%), m-cresol (2.841%), trans-sesquisabinene hydrate (2.128%), 4-hydroxy-2-methylacetophenone (1.735%), and (Z)-9-pentadecenol (1.509%). Application of AO improved the condition of UV-B radiation-induced damaged skin, and the mechanism of action was found to be related to inhibition of the production of inflammatory cytokines. These results highlight the potential application of AO for the development of skin care products.


Asunto(s)
Angelica/química , Aceites Volátiles/química , Aceites Volátiles/farmacología , Envejecimiento de la Piel/efectos de los fármacos , Envejecimiento de la Piel/efectos de la radiación , Protectores Solares/química , Protectores Solares/farmacología , Rayos Ultravioleta/efectos adversos , Animales , Femenino , Ratones , Ratones Pelados , Piel/efectos de los fármacos , Piel/patología , Piel/efectos de la radiación
5.
J Sci Med Sport ; 18(4): 388-93, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25127530

RESUMEN

OBJECTIVES: To explore the hip and knee joint kinematics as well as muscle activation between participants with patellofemoral pain syndrome (PFPS) and controls, and to investigate the immediate effect of proximal femoral rotational taping on pain, joint kinematics, and muscle activation during single-leg squat (SLS). DESIGN: Cross-sectional study. METHODS: Sixteen female participants with PFPS, and eight healthy female controls participated. Three-dimensional hip and patellar kinematics measured by electromagnetic tracking system, hip (gluteus maximus and gluteus medius) and thigh (rectus femoris) muscle activation measured by EMG, and subjective report of pain were recorded during SLS in three randomized conditions of no tape, sham taping, and femoral rotational taping with kinesiotape. RESULTS: Without taping, compared with controls, PFPS group had increased hip adduction angle (23.5±11.3° vs. 15.8±7.3°) during SLS. Additionally, PFPS group exhibited lesser rectus femoris activity during the initial 0-15° of SLS. Application of both femoral rotational and sham tapes reduced pain for PFPS group. Compared with no tape or sham tape, femoral rotational tape significantly shifted the patella into more posterior (1.59±0.83cm in no tape vs. 1.54±0.87cm in sham tape vs. 1.32±0.72cm in femoral rotational tape) and distal (-2.49±0.95cm vs. -2.64±0.80cm vs. -3.11±0.77cm) positions in the PFPS group. CONCLUSIONS: Femoral rotational taping could alter patellofemoral kinematics and decrease pain in treatment of young female participants with PFPS.


Asunto(s)
Articulación de la Cadera/fisiopatología , Articulación de la Rodilla/fisiopatología , Síndrome de Dolor Patelofemoral/fisiopatología , Síndrome de Dolor Patelofemoral/terapia , Modalidades de Fisioterapia , Adulto , Cinta Atlética , Fenómenos Biomecánicos , Estudios de Casos y Controles , Estudios Transversales , Prueba de Esfuerzo , Femenino , Humanos , Extremidad Inferior/fisiopatología , Contracción Muscular , Dimensión del Dolor , Músculo Cuádriceps/fisiopatología , Adulto Joven
6.
Man Ther ; 20(3): 427-32, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25435131

RESUMEN

BACKGROUND: Assessment of scapular dyskinesis (SD) is of clinical interest, as SD is believed to be related to shoulder pathology. However, no clinical assessment with sufficient reliability to identify SD and provide treatment strategies is available. OBJECTIVES: The purpose of this study was to investigate the reliability of the comprehensive SD classification method. DESIGN: Cross-sectional reliability study. METHOD: Sixty subjects with unilateral shoulder pain were evaluated by two independent physiotherapists with a visual-based palpation method. SD was classified as single abnormal scapular pattern [inferior angle (pattern I), medial border (pattern II), superior border of scapula prominence or abnormal scapulohumeral rhythm (pattern III)], a mixture of the above abnormal scapular patterns, or normal pattern (pattern IV). The assessment of SD was evaluated as subjects performed bilateral arm raising/lowering movements with a weighted load in the scapular plane. Percentage of agreement and kappa coefficients were calculated to determine reliability. RESULTS: Agreement between the 2 independent physiotherapists was 83% (50/60, 6 subjects as pattern III and 44 subjects as pattern IV) in the raising phase and 68% (41/60, 5 subjects as pattern I, 12 subjects as pattern II, 12 subjects as pattern IV, 12 subjects as mixed patterns I and II) in the lowering phase. The kappa coefficients were 0.49-0.64. CONCLUSIONS: We concluded that the visual-based palpation classification method for SD had moderate to substantial inter-rater reliability. The appearance of different types of SD was more pronounced in the lowering phase than in the raising phase of arm movements.


Asunto(s)
Discinesias/clasificación , Palpación/métodos , Rango del Movimiento Articular/fisiología , Escápula/fisiopatología , Articulación del Hombro/fisiopatología , Estudios Transversales , Discinesias/diagnóstico , Femenino , Humanos , Masculino , Variaciones Dependientes del Observador , Examen Físico/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
7.
Man Ther ; 19(4): 349-54, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24650638

RESUMEN

We determined whether the degree of symptom-related functional disability was related to daily physical activity of the shoulder in subjects with stiff shoulders (SSs). Responsiveness and a clinically meaningful level of discrimination between improvement and non-improvement for shoulder physical activity (SPA) were determined. Twenty-six subjects with SSs participated. Shoulder physical activity was assessed by RT3 accelerometers fixed on the humerus during daily 14-h data collection periods twice a week for 2 weeks. A moderate correlation coefficient was found between SPA and functional disability (ß = .47). Based on our cohort design and sample, we suggest that SPA (higher than 101.8 counts, hard-moderate or hard tasks) during daily activity are associated with (with at least 83% probability) non-improvement in an individual with SS. Compared to the non-improvement group, the improvement group had less duration of sedentary activity, less frequency and duration of hard tasks, and more frequency and duration of easy tasks (p < 0.01). Appropriate guidance on shoulder physical activities for subjects with SS is important to consider in rehabilitation strategies for these subjects. In our sample, a hard level of shoulder physical activity and sedentary activity should be cautious for these subjects. Further study is needed to validate therapeutic effect of physical activity on the course of patient improvement in subjects with SSs.


Asunto(s)
Acelerometría/instrumentación , Evaluación de la Discapacidad , Rango del Movimiento Articular/fisiología , Articulación del Hombro/fisiopatología , Dolor de Hombro/diagnóstico , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Actividad Motora/fisiología , Dimensión del Dolor , Curva ROC , Dolor de Hombro/rehabilitación , Análisis y Desempeño de Tareas
8.
J Electromyogr Kinesiol ; 23(1): 267-74, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23123099

RESUMEN

BACKGROUND: Muscle imbalance between serratus anterior (SA), upper trapezius (UA), middle trapezius (MT), and lower trapezius (LT) muscles has been observed in subjects with subacromial impingement syndrome (SAIS). OBJECTIVE: (1) To investigate the effect of electromyography (EMG) biofeedback training on muscle balance ratios and scapular kinematics in healthy adults and subjects with SAIS. (2) To investigate whether the effects of EMG biofeedback on muscle balance ratios are different between groups. DESIGN: Twelve healthy adults and 13 subjects with SAIS were recruited in this study. EMG was used to record the activity of scapular muscles. The ratios (UT/SA, UT/MT, and UT/LT) during exercises with/without EMG biofeedback were calculated. Scapular kinematics were recorded before and after exercises with/without EMG biofeedback. RESULTS: For the subjects with SAIS, muscle balance ratios were lower during forward flexion with EMG biofeedback than during exercise only (UT/SA: 70.3-45.2; UT/LT: 124.8-94.6). Additionally, similar results were found during side-lying external rotation (UT/MT: 58.5-36.4). For the scapular upward rotation and tipping in both groups, there were no significant differences with and without EMG biofeedback. CONCLUSION: EMG biofeedback improved the scapular muscular balance during training exercises in both groups. Further clinical trials should investigate the long-term effects of EMG biofeedback.


Asunto(s)
Electromiografía/métodos , Contracción Muscular , Músculo Esquelético/fisiopatología , Neurorretroalimentación/métodos , Escápula/fisiopatología , Síndrome de Abducción Dolorosa del Hombro/fisiopatología , Síndrome de Abducción Dolorosa del Hombro/rehabilitación , Adolescente , Adulto , Femenino , Humanos , Masculino , Actividad Motora , Equilibrio Postural , Síndrome de Abducción Dolorosa del Hombro/diagnóstico , Articulación del Hombro/fisiopatología , Resultado del Tratamiento , Adulto Joven
9.
Man Ther ; 16(2): 172-6, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21075671

RESUMEN

We investigated whether the RT3 accelerometer can be used to discriminate and characterize the different levels of shoulder physical activity (SPA) in both patients and healthy adults. Twenty healthy adults and 20 patients with shoulder disorders (SDs) performed activities at 5 levels of difficulty (easy, easy-moderate, moderate, hard-moderate, hard) with the same RT3 accelerometer fixed on the arm. The Vector Magnitude (VM) is the square root of the sum of squares from each axis to determine the overall magnitude of activity. The SPA counts of healthy group were significantly higher than the patient group in every level except easy (31-38 VM counts difference, p < 0.01). For both groups, the hard task demonstrated higher counts as compared to the other tasks. The easy task showed lower counts as compared to the other tasks. In the patient group, significant correlation between FLEX-SF scores and counts from the RT3 (R = -0.72, p < 0.05) was found in the moderate tasks. The results of this study showed that RT3 can be a potential measurement tool to (1) characterize the difference of SPA between two groups; and (2) partially discriminate the different levels of SPA. The correlations between self-reported function scores and SPA RT3 counts are dependent on self-reported task difficulty.


Asunto(s)
Ergometría/instrumentación , Artropatías/diagnóstico , Articulación del Hombro , Adulto , Fenómenos Biomecánicos , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados
10.
Genes Dev ; 20(15): 2067-81, 2006 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-16847351

RESUMEN

The synaptonemal complex (SC) is a proteinaceous complex that apparently mediates synapsis between homologous chromosomes during meiotic prophase. In Saccharomyces cerevisiae, the Zip1 protein is the integral component of the SC. In the absence of a DNA double-strand break or the SC initiation protein Zip3, Zip1 proteins aggregate to form a polycomplex (PC). In addition, Zip1 is also responsible for DSB-independent nonhomologous centromere coupling at early meiotic prophase. We report here that Zip3 is a SUMO (small ubiquitin-related modifier) E3 ligase and that Zip1 is a binding protein for SUMO-conjugated products. Our results also suggest that at early meiotic prophase, Zip1 interacts with Zip3-independent Smt3 conjugates (e.g., Top2) to promote nonhomologous centromere coupling. At and after mid-prophase, the Zip1 protein begins to associate with Zip3-dependent Smt3 conjugates (e.g., Red1) along meiotic chromosomes in the wild-type cell to form SCs and with Smt3 polymeric chains in the zip3 mutant to form PCs.


Asunto(s)
Meiosis , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/fisiología , Complejo Sinaptonémico/fisiología , Secuencia de Aminoácidos , Centrómero/fisiología , Cromosomas Fúngicos , Datos de Secuencia Molecular , Proteínas Nucleares , Profase , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crecimiento & desarrollo , Proteínas de Saccharomyces cerevisiae/genética , Homología de Secuencia de Aminoácido
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