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1.
Chem Rev ; 122(13): 11604-11674, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35653785

RESUMEN

Chitin, a fascinating biopolymer found in living organisms, fulfills current demands of availability, sustainability, biocompatibility, biodegradability, functionality, and renewability. A feature of chitin is its ability to structure into hierarchical assemblies, spanning the nano- and macroscales, imparting toughness and resistance (chemical, biological, among others) to multicomponent materials as well as adding adaptability, tunability, and versatility. Retaining the inherent structural characteristics of chitin and its colloidal features in dispersed media has been central to its use, considering it as a building block for the construction of emerging materials. Top-down chitin designs have been reported and differentiate from the traditional molecular-level, bottom-up synthesis and assembly for material development. Such topics are the focus of this Review, which also covers the origins and biological characteristics of chitin and their influence on the morphological and physical-chemical properties. We discuss recent achievements in the isolation, deconstruction, and fractionation of chitin nanostructures of varying axial aspects (nanofibrils and nanorods) along with methods for their modification and assembly into functional materials. We highlight the role of nanochitin in its native architecture and as a component of materials subjected to multiscale interactions, leading to highly dynamic and functional structures. We introduce the most recent advances in the applications of nanochitin-derived materials and industrialization efforts, following green manufacturing principles. Finally, we offer a critical perspective about the adoption of nanochitin in the context of advanced, sustainable materials.


Asunto(s)
Quitina , Nanoestructuras , Biopolímeros , Quitina/química , Nanoestructuras/química
2.
J Med Internet Res ; 26: e51706, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39116439

RESUMEN

BACKGROUND: Temporal bone computed tomography (CT) helps diagnose chronic otitis media (COM). However, its interpretation requires training and expertise. Artificial intelligence (AI) can help clinicians evaluate COM through CT scans, but existing models lack transparency and may not fully leverage multidimensional diagnostic information. OBJECTIVE: We aimed to develop an explainable AI system based on 3D convolutional neural networks (CNNs) for automatic CT-based evaluation of COM. METHODS: Temporal bone CT scans were retrospectively obtained from patients operated for COM between December 2015 and July 2021 at 2 independent institutes. A region of interest encompassing the middle ear was automatically segmented, and 3D CNNs were subsequently trained to identify pathological ears and cholesteatoma. An ablation study was performed to refine model architecture. Benchmark tests were conducted against a baseline 2D model and 7 clinical experts. Model performance was measured through cross-validation and external validation. Heat maps, generated using Gradient-Weighted Class Activation Mapping, were used to highlight critical decision-making regions. Finally, the AI system was assessed with a prospective cohort to aid clinicians in preoperative COM assessment. RESULTS: Internal and external data sets contained 1661 and 108 patients (3153 and 211 eligible ears), respectively. The 3D model exhibited decent performance with mean areas under the receiver operating characteristic curves of 0.96 (SD 0.01) and 0.93 (SD 0.01), and mean accuracies of 0.878 (SD 0.017) and 0.843 (SD 0.015), respectively, for detecting pathological ears on the 2 data sets. Similar outcomes were observed for cholesteatoma identification (mean area under the receiver operating characteristic curve 0.85, SD 0.03 and 0.83, SD 0.05; mean accuracies 0.783, SD 0.04 and 0.813, SD 0.033, respectively). The proposed 3D model achieved a commendable balance between performance and network size relative to alternative models. It significantly outperformed the 2D approach in detecting COM (P≤.05) and exhibited a substantial gain in identifying cholesteatoma (P<.001). The model also demonstrated superior diagnostic capabilities over resident fellows and the attending otologist (P<.05), rivaling all senior clinicians in both tasks. The generated heat maps properly highlighted the middle ear and mastoid regions, aligning with human knowledge in interpreting temporal bone CT. The resulting AI system achieved an accuracy of 81.8% in generating preoperative diagnoses for 121 patients and contributed to clinical decision-making in 90.1% cases. CONCLUSIONS: We present a 3D CNN model trained to detect pathological changes and identify cholesteatoma via temporal bone CT scans. In both tasks, this model significantly outperforms the baseline 2D approach, achieving levels comparable with or surpassing those of human experts. The model also exhibits decent generalizability and enhanced comprehensibility. This AI system facilitates automatic COM assessment and shows promising viability in real-world clinical settings. These findings underscore AI's potential as a valuable aid for clinicians in COM evaluation. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2000036300; https://www.chictr.org.cn/showprojEN.html?proj=58685.


Asunto(s)
Inteligencia Artificial , Otitis Media , Hueso Temporal , Tomografía Computarizada por Rayos X , Humanos , Otitis Media/diagnóstico por imagen , Hueso Temporal/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Enfermedad Crónica , Estudios Retrospectivos , Femenino , Masculino , Persona de Mediana Edad , Imagenología Tridimensional/métodos , Adulto , Redes Neurales de la Computación
3.
Small ; 19(39): e2300686, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37147774

RESUMEN

Non-equilibrium multiphase systems are formed by mixing two immiscible nanoparticle dispersions, leading to bicontinuous emulsions that template cryogels with interconnected, tortuous channels. Herein, a renewable, rod-like biocolloid (chitin nanocrystals, ChNC) is used to kinetically arrest bicontinuous morphologies. Specifically, it is found that ChNC stabilizes intra-phase jammed bicontinuous systems at an ultra-low particle concentration (as low as 0.6 wt.%), leading to tailorable morphologies. The synergistic effects of ChNC high aspect ratio, intrinsic stiffness, and interparticle interactions produce hydrogelation and, upon drying, lead to open channels bearing dual characteristic sizes, suitably integrated into robust bicontinuous ultra-lightweight solids. Overall, it demonstrates the successful formation of ChNC-jammed bicontinuous emulsions and a facile emulsion templating route to synthesize chitin cryogels that form unique super-macroporous networks.

4.
Eur Arch Otorhinolaryngol ; 280(5): 2065-2072, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36576531

RESUMEN

BACKGROUND: It is yet unknown if the ApneaGraph200 system can replace the Polysomnography system (PSG), which is now the gold standard for obstructive sleep apnea (OSA) diagnosis. We performed a meta-analysis to evaluate the difference in apnea hypopnea index and lowest oxygen saturation levels between the AG200 system and PSG system. METHODS: Utilizing PubMed, Elsevier, Wanfang, and China National Knowledge Internet (CNKI), a thorough literature search was carried out. Eligible studies contrasting the AG200 system and the PSG system were found by two separate researchers. Review Manager (version 5.3) was adopted for data synthesis. RESULTS: The meta-analysis A pooled the comparison of AHI between the AG and PSG groups, and included seven studies involving a total of 419 participants, which revealed that there was a significant difference in AHI between the above two diagnostic methods (standard mean difference (SMD) = - 0.19, 95% confidence interval (CI) = - 0.32 to - 0.05, P = 0.008). As a supplementary, meta-analysis B pooled the comparison of lowest oxygen saturation between the AG and PSG groups and included five studies involving a total of 224 participants. It revealed that there was no significant difference between the AG group and the PSG group (SMD = 0.09, 95% CI - 0.24 to 0.43, P = 0.58). CONCLUSION: The ApneaGraph200 system can be used for the initial screening of OSA patients, but it is not a complete alternative to polysomnography for the diagnosis and severity of the OSA condition.


Asunto(s)
Apnea Obstructiva del Sueño , Humanos , Polisomnografía/métodos , Revisiones Sistemáticas como Asunto , Metaanálisis como Asunto , Apnea Obstructiva del Sueño/cirugía , China
5.
Eur Arch Otorhinolaryngol ; 280(5): 2091-2097, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36658368

RESUMEN

OBJECTIVE: There was disagreement over the association between serum/plasma homocysteine (HCY) levels and sudden sensorineural hearing loss (SSNHL). Through the use of a meta-analysis, this study aims to determine whether there is a significant difference in serum homocysteine levels between the SSNHL group and the control group. DESIGN: The Cochrane Library, EMBASE, and PubMed databases were all thoroughly searched. The two independent reviewers thoroughly examined the initially searched articles. The data results were calculated by standard mean difference (SMD) or odds ratios (OR). Review Manager (version 5.3) was applied to statistical data. STUDY SAMPLE: There were 766 participants in the 6 trials with continuous outcomes that were part of the meta-analysis A. In addition, meta-analysis B, which included 961 people, contained a total of 3 studies with dichotomous results. RESULTS: Both meta-analyses revealed the same conclusion that serum/plasma HCY levels in the SSNHL patients are higher than those in the controls (SMD 0.41, 95 % confidence interval (CI) 0.11 to 0.72, P < 0.01; OR 3.27, 95 % CI 2.16 to 4.94, P < 0.01). CONCLUSION: This study demonstrated that the SSNHL patients' serum/plasma HCY levels were greater than those of the control group.


Asunto(s)
Pérdida Auditiva Sensorineural , Pérdida Auditiva Súbita , Humanos , Bases de Datos Factuales , Homocisteína
6.
Sleep Breath ; 25(1): 9-16, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32399702

RESUMEN

PURPOSE: The pathogenesis of cardiovascular disease (CVD) in patients with obstructive sleep apnea (OSA) is unclear. Several studies have suggested that CVD may be caused by oxidative stress from chronic intermittent hypoxia and associated vascular endothelial dysfunction. Oxidative stress in patients with OSA can induce endothelial cell apoptosis, aggravate vascular endothelial damage, and promote the expression of redox-sensitive genes and adhesion molecules. No meta-analysis has explored whether or not OSA is related to nitric oxide (NO). METHOD: To assess the association between serum/plasma NO levels and OSA, we performed a meta-analysis of the literature on the subject to grade the strength of evidence. RESULTS: OSA was significantly related to decreased serum or plasma NO levels (WMD = - 11.66, 95% CI - 17.21 to - 6.11; P < 0.01). Among the studies analyzed, there was high degree of heterogeneity (I2 = 79%, P < 0.01). Sensitivity analysis showed that after omitting any single study or converting a random effects model (REM) to a fixed effects model (FEM), the main results still held. CONCLUSIONS: This meta-analysis suggests a strong correlation between OSA and serum or plasma NO levels which may explain the link between intermittent hypoxia of OSA and risk of CVD. The strength of this finding may spur further basic and clinical research into vascular endothelial dysfunction in patients with OSA.


Asunto(s)
Óxido Nítrico/sangre , Apnea Obstructiva del Sueño/sangre , Humanos
7.
Am J Gastroenterol ; 115(5): 766-773, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32287140

RESUMEN

OBJECTIVE: Since the outbreak of Coronavirus Disease 2019 (COVID-19) in December 2019, various digestive symptoms have been frequently reported in patients infected with the virus. In this study, we aimed to further investigate the prevalence and outcomes of COVID-19 patients with digestive symptoms. METHODS: In this descriptive, cross-sectional, multicenter study, we enrolled confirmed patients with COVID-19 who presented to 3 hospitals from January 18, 2020, to February 28, 2020. All patients were confirmed by real-time polymerase chain reaction and were analyzed for clinical characteristics, laboratory data, and treatment. Data were followed up until March 18, 2020. RESULTS: In the present study, 204 patients with COVID-19 and full laboratory, imaging, and historical data were analyzed. The average age was 52.9 years (SD ± 16), including 107 men and 97 women. Although most patients presented to the hospital with fever or respiratory symptoms, we found that 103 patients (50.5%) reported a digestive symptom, including lack of appetite (81 [78.6%] cases), diarrhea (35 [34%] cases), vomiting (4 [3.9%] cases), and abdominal pain (2 [1.9%] cases). If lack of appetite is excluded from the analysis (because it is less specific for the gastrointestinal tract), there were 38 total cases (18.6%) where patients presented with a gastrointestinal-specific symptom, including diarrhea, vomiting, or abdominal pain. Patients with digestive symptoms had a significantly longer time from onset to admission than patients without digestive symptoms (9.0 days vs 7.3 days). In 6 cases, there were digestive symptoms, but no respiratory symptoms. As the severity of the disease increased, digestive symptoms became more pronounced. Patients with digestive symptoms had higher mean liver enzyme levels, lower monocyte count, longer prothrombin time, and received more antimicrobial treatment than those without digestive symptoms. DISCUSSION: We found that digestive symptoms are common in patients with COVID-19. Moreover, these patients have a longer time from onset to admission, evidence of longer coagulation, and higher liver enzyme levels. Clinicians should recognize that digestive symptoms, such as diarrhea, are commonly among the presenting features of COVID-19 and that the index of suspicion may need to be raised earlier in at-risk patients presenting with digestive symptoms. However, further large sample studies are needed to confirm these findings.


Asunto(s)
Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/epidemiología , Enfermedades Gastrointestinales/epidemiología , Neumonía Viral/diagnóstico , Neumonía Viral/epidemiología , Adulto , Anciano , COVID-19 , China/epidemiología , Infecciones por Coronavirus/terapia , Estudios Transversales , Femenino , Enfermedades Gastrointestinales/terapia , Enfermedades Gastrointestinales/virología , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/terapia , Prevalencia , Resultado del Tratamiento
8.
Med Sci Monit ; 26: e919501, 2020 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-32221272

RESUMEN

BACKGROUND This study aimed to elucidate the possible activity of the mitochondrial-mediated apoptotic pathway (MMAP) in obstructive sleep apnea-hypopnea syndrome (OSAHS). MATERIAL AND METHODS A control group, a mild OSAHS group, a moderate OSAHS group, and a severe OSAHS group were included. Masson staining, hematoxylin and eosin staining, and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay were performed to assess collagen fiber hyperplasia, pathological morphology, and cell apoptosis, respectively, in muscle samples. RESULTS In the OSAHS groups, the palatopharyngeal muscle fibers were larger, with apparent hypertrophy and increased elastic fiber content. The proportions of type I fibers were markedly higher in the control group than in the moderate and severe OSAHS groups (P<0.05). Moreover, apoptosis was significantly enhanced in the muscle cells of the OSAHS groups. The Bax expression levels gradually increased across the 4 groups (lowest in the control group and highest in the severe OSAHS group) (P<0.05); conversely, the p38 and p62 expression levels did not significantly differ among groups (P>0.05). CONCLUSIONS A decrease in the proportion of the different fiber types can result in collapse of the upper airway. The pathogenesis of OSAHS appears to involve muscle cell apoptosis via MMAP.


Asunto(s)
Mitocondrias/patología , Fibras Musculares Esqueléticas/patología , Músculos Faríngeos/patología , Apnea Obstructiva del Sueño/patología , Adulto , Apoptosis , Miosinas Cardíacas/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fibras Musculares Esqueléticas/citología , Cadenas Pesadas de Miosina/metabolismo , Músculos Faríngeos/citología , Músculos Faríngeos/cirugía , Polisomnografía , Estudios Prospectivos , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/cirugía , Proteína X Asociada a bcl-2/metabolismo
9.
Biomacromolecules ; 20(5): 2105-2114, 2019 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-30983326

RESUMEN

Alternatives to petroleum-based plastics are of great significance not only from the point of view of their scientific and practical impact but to reduce the environmental footprint. Inspired by the composition and structure of wood's cell walls, we used phenolic acids to endow cellulosic fibers with new properties. The fiber dissolution and homogeneous modification were performed with a recyclable ionic liquid (IL) (tetrabutylammonium acetate ([N4444][OAc]):dimethyl sulfoxide) to attain different levels of reaction activity for three phenolic acids ( p-hydroxybenzoic acid, vanillic acid, and syringic acid). The successful autocatalytic Fischer esterification reaction was thoroughly investigated by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, elemental analysis, and nuclear magnetic resonance spectroscopy (13C CP-MAS, diffusion-edited 1H NMR and multiplicity-edited heteronuclear single quantum coherence). Control of the properties of cellulose in the dispersed state, welding, and IL plasticization were achieved during casting and recrystallization to the cellulose II crystalline allomorph. Films of cellulose carrying grafted acids were characterized with respect to properties relevant to packaging materials. Most notably, despite the low degree of esterification (DS < 0.25), the films displayed a remarkable strength (3.5 GPa), flexibility (strains up to 35%), optical transparency (>90%), and water resistance (WCA ∼ 90°). Moreover, the measured water vapor barrier was found to be similar to that of poly(lactic acid) composite films. Overall, the results contribute to the development of the next-generation green, renewable, and biodegradable films for packaging applications.


Asunto(s)
Plásticos Biodegradables/síntesis química , Celulosa/análogos & derivados , Líquidos Iónicos/química , Esterificación , Fenoles/química , Embalaje de Productos/métodos , Resistencia a la Tracción
10.
Sleep Breath ; 23(2): 389-397, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29987514

RESUMEN

BACKGROUND: Obstructive sleep apnea hypopnea syndrome (OSAHS) means apnea and hypopnea caused by partial or complete obstruction of upper airway collapse during sleep. Gastroesophageal reflux disease (GERD) is believed to be associated with various manifestations in the otorhinolaryngology and has been found to be an additional risk factor for OSAHS. AIM: A meta-analysis was performed to identify the association between obstructive sleep apnea hypopnea syndrome and gastroesophageal reflux disease. METHODS: To identify eligible original articles, we searched a series of computerized databases, including Medline via PubMed, EMBASE, Web of Science, and CNKI with a systematic searching strategy. The characteristics of each article and pooled odds ratios (ORs) with corresponding confidence intervals (CIs) were calculated and subgroup analysis was performed to analyze the source of heterogeneity. RESULTS: A total of 2699 patients from seven articles were included in the meta-analysis. We identified a significant relationship between obstructive sleep apnea syndrome and gastroesophageal reflux disease, with a pooled OR of 1.75 (95% CI 1.18-2.59, P < 0.05). The pooled data was calculated under the random-effects model as a significant moderate heterogeneity was found among the meta-analysis. CONCLUSIONS: The meta-analysis showed that there was a significant correlation between obstructive sleep apnea hypopnea syndrome and gastroesophageal reflux disease.


Asunto(s)
Reflujo Gastroesofágico/complicaciones , Apnea Obstructiva del Sueño/etiología , Humanos , Oportunidad Relativa , Factores de Riesgo
11.
Sleep Breath ; 23(2): 559-565, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30343435

RESUMEN

PURPOSE: Although mixed sleep apnea (MSA) is one of the three types of sleep apnea, it is not considered a separate disease entity. It is generally seen as a part of obstructive sleep apnea-hypopnea syndrome (OSAHS), but its implications are often ignored. In this study, we examined its features and the potential impact on OSAHS patients. METHODS: Subjects diagnosed with OSAHS by polysomnography (PSG) were enrolled. All participants underwent physical checkups and tests of blood biochemistry. They were anthropometrically, clinically, and polysomnographically studied. RESULTS: MSA events were common in patients with severe OSAHS patients. There were significant differences between the pure OSAHS group and its mixed counterpart in apnea-hypopnea indices during REM (AHIREM) and non-REM (AHINREM) and in percentages of N2 or N3 sleep. Logistic regression analysis showed that, after adjustment of other parameters, patients with MSA events were mostly male, had higher body mass index (BMI), higher scores on Epworth Sleepiness Scales (ESS), higher triglyceride (TG) levels, and higher apnea-hypopnea index (AHI). The combined predictive probability of the aforementioned variables was 0.766 (95% CI = 0.725~0.806; sensitivity 61.6%, specificity 82.1%). CONCLUSIONS: Our study suggested that MSA was related to the stability of the ventilatory control in OSAHS patients. MSA events occur more frequently in patients with severe OSAHS, and male gender, obesity, daytime sleepiness, and elevated TG levels were risk factors for the mixed OSAHS.


Asunto(s)
Polisomnografía , Síndromes de la Apnea del Sueño/diagnóstico , Apnea Obstructiva del Sueño/diagnóstico , Adulto , Factores de Edad , Trastornos de Somnolencia Excesiva/diagnóstico , Femenino , Humanos , Masculino , Obesidad/complicaciones , Factores de Riesgo , Factores Sexuales
12.
Respir Res ; 19(1): 194, 2018 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-30285853

RESUMEN

BACKGROUND: Obstructive sleep apnea-hypopnea syndrome (OSAHS) is prone to being complicated with various cardiovascular, cerebrovascular and metabolic conditions. OSAHS, due to its multifactorial nature, entails individualized and comprehensive treatment. So far, no well-established diagnostic criteria for the disease are available. In recent years, miRNA has been shown to be a sensitive biomarker suggestive of the progression and prognosis of many diseases. In this study, we examined some serum miRNAs in healthy OSAHS (OSAHS patients without complication) and OSAHS with arterial hypertension, with an attempt to understand the potential effects on the disease, improve the diagnosis of OSAHS and find OSAHS-related diagnostic markers. METHODS: Against various diagnostic criteria, participants were divided into three groups: healthy OSAHS, OSAHS with arterial hypertension and healthy controls. Their serum miRNA profiles were assessed by microarray technology, and then differentially expressed miRNAs were verified by quantitative real-time PCR (qRT-PCR). The receiver operating characteristic (ROC) curves of miRNAs were constructed and the areas under the curve (AUC) were calculated. Meanwhile, the miRNAs were subjected to logistic regression analysis. The target genes were bioinformatically assessed, their functions and signaling pathways further determined and eventually an miRNA-gene network was established. RESULTS: Analysis with the miRNA array exhibited that, compared with the control group, 12 differentially expressed miRNAs were found in healthy OSAHS, and 33 were found in OSAHS with arterial hypertension. The expression of miR-126-3p, let-7d-5p, miR-7641 and miR-1233-5p, miR-320b, miR-145-5p, miR-107, miR-26a-5p were validated by using qRT-PCR. Bioinformatics analysis predicted that the potential target genes of these miRNAs might be involved in metabolism, and the regulation of endothelial cells and nervous system. Moreover, the ROC analysis showed that the using miR-145-5p and let-7d-5p in combination can identify the healthy OSAHS, presence of miR-126-3p, miR-26a-5p and miR-107 was well indicative of OSAHS with arterial hypertension. CONCLUSIONS: A cluster of dysregulation miRNAs have been found to be involved in the development of OSAHS patients. Moreover, these miRNAs might be used to be potential diagnostic and early warning markers.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Hipertensión/diagnóstico , Hipertensión/genética , MicroARNs/genética , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/genética , Adulto , Diagnóstico Precoz , Femenino , Redes Reguladoras de Genes/genética , Marcadores Genéticos/genética , Humanos , Hipertensión/metabolismo , Masculino , MicroARNs/biosíntesis , Persona de Mediana Edad , Síndromes de la Apnea del Sueño/diagnóstico , Síndromes de la Apnea del Sueño/genética , Síndromes de la Apnea del Sueño/metabolismo , Apnea Obstructiva del Sueño/metabolismo
13.
Biomacromolecules ; 19(12): 4565-4575, 2018 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-30412387

RESUMEN

This work investigates multifunctional composite films synthesized with cellulose nanofibers (CNFs) and poly(vinyl alcohol) (PVA). First, TEMPO-oxidized CNFs were modified in the heterogeneous phase with benzophenone, diisocyanate, and epoxidized soybean oil via esterification reactions. A thorough characterization was carried out via elemental analysis as well as FT-IR and X-ray photoelectron spectroscopies and solid-state NMR. Following, the surface-modified CNFs were combined with PVA to endow composite films with UV-absorbing capabilities while increasing their thermomechanical strength and maintaining a high light transmittance. Compared to neat PVF films, the tensile strength, Young modulus, and elongation of the films underwent dramatic increases upon addition of the reinforcing phase (maximum values of ∼96 MPa, ∼ 714 MPa, and ∼350%, respectively). A high UV blocking performance, especially in the UVB region, was observed for the introduced multifunctional PVA films at CNF loadings below 5 wt %. The trade-off between modified nanofibril function as interfacial reinforcement and aggregation leads to an optimum loading. The results indicate promising applications, for example, in active packaging.


Asunto(s)
Celulosa Oxidada/química , Celulosa/química , Nanocompuestos/química , Nanofibras/química , Polisacáridos/química , Alcohol Polivinílico/química , Espectroscopía Infrarroja por Transformada de Fourier , Resistencia a la Tracción , Rayos Ultravioleta
14.
J Nurs Care Qual ; 31(2): 161-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26855268

RESUMEN

Pediatric early warning scores in an emergency department may be used in routine patient evaluation of illness severity and resource allocation, thereby positively impacting quality and safety in pediatric care. This prospective nursing study assessed the feasibility and reliability of pediatric early warning scores in a busy, inner-city, level 1 trauma center pediatric emergency department. The pediatric early warning scores demonstrated high interrater reliability (degree of agreement among scorers) (intraclass correlation coefficient = 0.91) and intrarater reliability (multiple repetitions by a single scorer) (intraclass correlation coefficient = 0.90).


Asunto(s)
Servicio de Urgencia en Hospital/normas , Pediatría , Índice de Severidad de la Enfermedad , Índices de Gravedad del Trauma , Adolescente , Niño , Preescolar , Estudios de Factibilidad , Grupos Focales , Hospitales Urbanos , Humanos , Admisión del Paciente/normas , Estudios Prospectivos , Reproducibilidad de los Resultados , Triaje
15.
Sleep Breath ; 18(4): 687-94, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24463983

RESUMEN

PURPOSE: Continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnea hypopnea syndrome (OSAHS), but previous studies assessing the effect of CPAP on homocysteine (HCY) in patients with OSAHS yielded conflicting results. In this study, we conducted a meta-analysis to determine whether CPAP therapy could reduce plasma HCY levels. METHODS: Searches of PUBMED, SCI, and Elsevier databases were completed. Studies of adult patients with OSAHS who reported HCY levels pre- and post-CPAP treatment were collected by two independent reviewers. RevMan (version 5.2) and STATA (version 12.0) were used to perform data synthesis. RESULTS: A total of 6 studies involving 206 participants were included. Meta-analysis showed that the total weighted mean difference (WMD) for HCY levels was -0.62 units (95% confidence interval (CI) -1.21 to -0.04, P<0.05) post- and pre-CPAP therapy. Subgroup analysis showed that HCY was decreased nonsignificantly within 3 months after the therapy (WMD, -0.07, 95% CI -0.88 to 0.74, P>0.05), but it was significantly reduced after 3 months therapy (WMD, -1.22, 95% CI -2.07 to -0.38, P<0.05). CONCLUSIONS: This meta-analysis suggests that HCY levels were significantly reduced by CPAP therapy in patients with OSAHS and the HCY levels may be clinically recognized as a valuable indicator for OSAHS treatment, but the clinical significance of this finding as it relates to cardiovascular risk reduction in OSAHS patients warrants further study.


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua , Homocisteína/sangre , Apnea Obstructiva del Sueño/sangre , Apnea Obstructiva del Sueño/terapia , Humanos , Resultado del Tratamiento
16.
J Neuroeng Rehabil ; 11: 42, 2014 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-24661681

RESUMEN

BACKGROUND: Motor impairment is a major consequence of spinal cord injury (SCI). Earlier studies have shown that robotic gait orthosis (e.g., Lokomat) can improve an SCI individual's walking capacity. However, little is known about the differential responses among different individuals with SCI. The present longitudinal study sought to characterize the distinct recovery patterns of gait impairment for SCI subjects receiving Lokomat training, and to identify significant predictors for these patterns. METHODS: Forty SCI subjects with spastic hypertonia at their ankles were randomly allocated to either control or intervention groups. Subjects in the intervention group participated in twelve 1-hour Lokomat trainings over one month, while control subjects received no interventions. Walking capacity was evaluated in terms of walking speed, functional mobility, and endurance four times, i.e. baseline, 1, 2, and 4 weeks after training, using the 10-Meter-Walking, Timed-Up-and-Go, and 6-Minute-Walking tests. Growth Mixture Modeling, an analytical framework for stratifying subjects based on longitudinal changes, was used to classify subjects, based on their gait impairment recovery patterns, and to identify the effects of Lokomat training on these improvements. RESULTS: Two recovery classes (low and high walking capacity) were identified for each clinical evaluation from both the control and intervention groups. Subjects with initial high walking capacity (i.e. shorter Timed-Up-and-Go time, higher 10-Meter-Walking speed and longer 6-Minute-Walking distance) displayed significant improvements in speed and functional mobility (0.033 m/s/week and-0.41 s/week respectively); however no significant change in endurance was observed. Subjects with low walking capacity exhibited no significant improvement. The membership in these two classes-and thus prediction of the subject's gait improvement trajectory over time-could be determined by the subject's maximum voluntary torque at the ankle under both plantar-and dorsi-flexion contractions determined prior to any training. CONCLUSION: Our findings demonstrate that subjects responded to Lokomat training non-uniformly, and should potentially be grouped based on their likely recovery patterns using objective criteria. Further, we found that the subject's ankle torque can predict whether he/she would benefit most from Lokomat training prior to the therapy. These findings are clinically significant as they can help individualize therapeutic programs that maximize patient recovery while minimizing unnecessary efforts and costs.


Asunto(s)
Trastornos Neurológicos de la Marcha/rehabilitación , Marcha , Aparatos Ortopédicos , Recuperación de la Función , Robótica/instrumentación , Traumatismos de la Médula Espinal/rehabilitación , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fuerza Muscular/fisiología , Modalidades de Fisioterapia/instrumentación , Robótica/métodos
17.
J Neuroeng Rehabil ; 11: 46, 2014 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-24684813

RESUMEN

BACKGROUND: In incomplete spinal cord injury (iSCI), sensorimotor impairments result in severe limitations to ambulation. To improve walking capacity, physical therapies using robotic-assisted locomotor devices, such as the Lokomat, have been developed. Following locomotor training, an improvement in gait capabilities-characterized by increases in the over-ground walking speed and endurance-is generally observed in patients. To better understand the mechanisms underlying these improvements, we studied the effects of Lokomat training on impaired ankle voluntary movement, known to be an important limiting factor in gait for iSCI patients. METHODS: Fifteen chronic iSCI subjects performed twelve 1-hour sessions of Lokomat training over the course of a month. The voluntary movement was qualified by measuring active range of motion, maximal velocity peak and trajectory smoothness for the spastic ankle during a movement from full plantar-flexion (PF) to full dorsi-flexion (DF) at the patient's maximum speed. Dorsi- and plantar-flexor muscle strength was quantified by isometric maximal voluntary contraction (MVC). Clinical assessments were also performed using the Timed Up and Go (TUG), the 10-meter walk (10MWT) and the 6-minute walk (6MWT) tests. All evaluations were performed both before and after the training and were compared to a control group of fifteen iSCI patients. RESULTS: After the Lokomat training, the active range of motion, the maximal velocity, and the movement smoothness were significantly improved in the voluntary movement. Patients also exhibited an improvement in the MVC for their ankle dorsi- and plantar-flexor muscles. In terms of functional activity, we observed an enhancement in the mobility (TUG) and the over-ground gait velocity (10MWT) with training. Correlation tests indicated a significant relationship between ankle voluntary movement performance and the walking clinical assessments. CONCLUSIONS: The improvements of the kinematic and kinetic parameters of the ankle voluntary movement, and their correlation with the functional assessments, support the therapeutic effect of robotic-assisted locomotor training on motor impairment in chronic iSCI.


Asunto(s)
Tobillo/fisiopatología , Movimiento/fisiología , Modalidades de Fisioterapia , Robótica/métodos , Traumatismos de la Médula Espinal/rehabilitación , Adulto , Anciano , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Actividad Motora/fisiología , Fuerza Muscular/fisiología , Modalidades de Fisioterapia/instrumentación , Rango del Movimiento Articular , Recuperación de la Función , Robótica/instrumentación , Traumatismos de la Médula Espinal/fisiopatología
18.
Int Forum Allergy Rhinol ; 14(3): 679-694, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37715589

RESUMEN

BACKGROUND: Endoscopic vidian neurectomy is expected to provide good therapeutic relief in patients with allergic rhinitis (AR) being refractory to medication therapy or conservative surgery. However, the evidence bases for its benefit remain debatable. In this study, we conducted a systematic review and meta-analysis to clarify the therapeutic role of various forms of vidian neurectomy in refractory AR. METHOD: Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were used to conduct a systematic review of primary studies that reported original patient data for endoscopic vidian neurectomy (EVN) and vidian-branch neurectomy, which includes selective vidian neurectomy (SVN) and posterior nasal neurectomy (PNN). The primary outcome was patient-reported outcome measures (PROMs), including the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) and Visual Analog Scale (VAS), to assess an improvement in nasal symptom severity and quality of patient's life. The incidence of surgical complications and other objective outcomes were considered secondary outcomes. RESULTS: This review included 24 clinical studies involving 1677 patients with refractory AR, of which 510 patients in six studies had combined chronic rhinosinusitis with nasal polyps (CRSwNP) and 95 patients in one study had combined asthma. Postoperative PROMs were significantly better than preoperatively in almost all patients who underwent vidianp (RQLQ: standardized mean difference [SMD] = 2.66, 95% confidence interval [CI] = 2.40-2.92, p < 0.001; VAS: SMD = 5.15, 95% CI = 4.29-6.02, p < 0.001) or vidian-branch neurectomy (RQLQ in PNN: SMD = 3.29, 95% CI = 2.45-4.13, p < 0.001; VAS in PNN: SMD = 4.38, 95% CI = 3.41-5.34, p < 0.001), and were generally better than in the conservative treatment group. Dividing with 18 months as the cutoff point, a subgroup analysis of the follow-up period was conducted, and the results showed that both long-term and short-term postoperative patients had considerably reduced symptoms compared to the preoperative period. The two surgical procedures, SVN and PNN, attributed to vidian-branch neurectomy have extremely few complications. However, EVN is more likely to cause dry eyes and palatal numbness, with no other serious complications. In patients with AR and CRSwNP, vidian or selective vidian neurectomy combined with functional endoscopic sinus surgery (FESS) is more effective than conventional FESS (RQLQ: SMD = 2.17, 95% CI = 1.66-2.69, p < 0.001; VAS: SMD = 6.42, 95% CI = 4.78-8.06, p < 0.001). For patients who have both AR and asthma, SVN with pharyngeal branch excision is a potential treatment option. CONCLUSION: EVN and vidian-branch neurectomy (including SVN and PNN) are effective treatments, but the former has a higher risk of complications. Additionally, vidian-branch neurectomy with FESS is beneficial for patients with mixed CRSwNP. SVN is a potential approach for patients with coexisting AR and asthma.


Asunto(s)
Asma , Rinitis Alérgica , Rinitis , Humanos , Calidad de Vida , Rinitis Alérgica/cirugía , Desnervación/métodos , Nariz , Asma/cirugía , Rinitis/cirugía
19.
Diagnostics (Basel) ; 14(18)2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39335707

RESUMEN

OBJECTIVE: This systematic review investigates the long-term effect of cochlear implantation (CI) on clinical outcomes in tinnitus patients with sensorineural hearing loss (SNHL). DATABASE SOURCES: PubMed, Embase, and the Cochrane Library were searched from inception to 30 April 2024. Manual searches of reference lists supplemented these searches when necessary. REVIEW METHODS: Original studies included in the meta-analysis had to contain comparative pre- and postoperative data for SNHL patients who underwent CI. Outcomes measured were the Tinnitus Handicap Inventory (THI), Visual Analog Scale (VAS), and Tinnitus Questionnaire (TQ). RESULTS: A total of 28 studies comprising 853 patients showed significant tinnitus improvement after CI: THI mean difference (MD) -14.02 [95%CI -15.29 to -12.76, p < 0.001], TQ MD -15.85 [95%CI -18.97 to -12.74, p < 0.05], and VAS MD -3.12 [95%CI -3.49 to -2.76, p < 0.05]. Subgroup analysis indicated a significant difference between follow-up periods in THI (p < 0.0001) and VAS loudness (p = 0.02). CONCLUSIONS: Cochlear implantation substantially improves tinnitus in patients with hearing loss, though the effect may diminish over time. Further research is needed to confirm these findings.

20.
Nanoscale ; 16(26): 12611-12623, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38881312

RESUMEN

Bio-based functional materials can be used to replace or limit the use of synthetic materials sourced from unsustainable sources. However, the potential of such materials remains largely unexplored. In this study, we demonstrate the use of weak AC electric fields to deposit ultra-thin piezoelectric films from cellulose nanocrystals (CNC). This is the first time electric fields are used to realize <50 nm thick uniform bio-based piezoelectric films wherein the bioparticles exhibit unidirectional arrangement. Interestingly, we found that the use of weak AC electric fields of suitable frequencies completely mitigates the coffee ring effect (CRE), which results in defect-free uniform ultra-thin films. Additionally, the electric fields appear to help in realizing unidirectional alignment of particles in the films, which enhances their piezoelectric properties. The method was also tested for chitin nanocrystals (ChNC), which have a similar aspect ratio but bear opposite polarity surface charges, and the influence of the field on coffee ring formation and particle orientation in CNC thin film deposition was validated. The phenomena can be attributed to the constant spatio-temporal curvature of the evaporating liquid film, the transient state between the three-phase contact (TPC) line, the electric field-dependent contact angle, and the permanent and field-induced dipole moments. These factors lead to particle polarization and alignment. The films have an optimum electrical frequency of deposition at which they are continuous and uniformly thin, have unidirectional alignment of particles, and function as a single dipole.

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