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1.
BMC Med Imaging ; 21(1): 127, 2021 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-34425762

RESUMO

BACKGROUND: Adenoid hypertrophy among orthodontic patients may be detected in lateral cephalograms. The study investigates the aerodynamic characteristics within the upper airway (UA) by means of computational fluid dynamics (CFD) simulation. Furthermore, airflow features are compared between subgroups according to the adenoidal nasopharyngeal (AN) ratios. METHODS: This retrospective study included thirty-five patients aged 9-15 years having both lateral cephalogram and cone beam computed tomography (CBCT) imaging that covered the UA region. The cases were divided into two subgroups according to the AN ratios measured on the lateral cephalograms: Group 1 with an AN ratio < 0.6 and Group 2 with an AN ratio ≥ 0.6. Based on the CBCT images, segmented UA models were created and the aerodynamic characteristics at inspiration and expiration were simulated by the CFD method for the two groups. The studied aerodynamic parameters were pressure drop (ΔP), maximum midsagittal velocity (Vms), maximum wall shear stress (Pws), and minimum wall static pressure (Pw). RESULTS: The maximum Vms exhibits nearly 30% increases in Group 2 at both inspiration (p = 0.013) and expiration (p = 0.045) compared to Group 1. For the other aerodynamic parameters such as ΔP, the maximum Pws, and minimum Pw, no significant difference is found between the two groups. CONCLUSIONS: The maximum Vms seems to be the most sensitive aerodynamic parameter for the groups of cases. An AN ratio of more than 0.6 measured on a lateral cephalogram may associate with a noticeably increased maximum Vms, which could assist clinicians in estimating the airflow features in the UA.


Assuntos
Tonsila Faríngea/anatomia & histologia , Cefalometria/métodos , Nasofaringe/anatomia & histologia , Adolescente , Criança , Tomografia Computadorizada de Feixe Cônico , Estudos Transversais , Feminino , Humanos , Masculino , Nasofaringe/diagnóstico por imagem , Nasofaringe/fisiologia , Radiografia Panorâmica , Estudos Retrospectivos
2.
BMC Oral Health ; 21(1): 123, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33731068

RESUMO

BACKGROUND: The effect of rapid maxillary expansion (RME) on the upper airway (UA) has been studied earlier but without a consistent conclusion. This study aims to evaluate the outcome of RME on the UA function in terms of aerodynamic characteristics by applying a computational fluid dynamics (CFD) simulation. METHODS: This retrospective cohort study consists of seventeen cases with two consecutive CBCT scans obtained before (T0) and after (T1) RME. Patients were divided into two groups with respect to patency of the nasopharyngeal airway as expressed in the adenoidal nasopharyngeal ratio (AN): group 1 was comprised of patients with an AN ratio < 0.6 and group 2 encompassing those with an AN ratio ≥ 0.6. CFD simulation at inspiration and expiration were performed based on the three-dimensional (3D) models of the UA segmented from the CBCT images. The aerodynamic characteristics in terms of pressure drop (ΔP), maximum midsagittal velocity (Vms), and maximum wall shear stress (Pws) were compared by paired t-test and Wilcoxon test according to the normality test at T0 and T1. RESULTS: The aerodynamic characteristics in UA revealed no statistically significant difference after RME. The maximum Vms (m/s) decreased from 2.79 to 2.28 at expiration after RME (P = 0.057). CONCLUSION: The aerodynamic characteristics were not significantly changed after RME. Further CFD studies with more cases are warranted.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Técnica de Expansão Palatina , Humanos , Maxila , Nariz , Estudos Retrospectivos
3.
J Clin Pediatr Dent ; 45(3): 208-215, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34192749

RESUMO

Objectives The present study evaluated the effect of rapid maxillary expansion (RME) on the morphology of the upper airway (UA) by calculating cross-sectional areas and volumes and comparing the effect in patients with a normal-sized adenoid with the effect in patients with an enlarged adenoid. Study design: Seventeen patients met the inclusion criteria. We constructed 3D models of the UA on cone-beam computed tomography images to calculate cross-sectional areas and volumes at the levels of the nasopharyngeal, retropalatal, and retroglossal airways. Patients were divided into two groups: group 1 was comprised of patients with an adenoidal nasopharyngeal (AN) ratio < 0.6 and group 2 with an AN ratio ≥ 0.6. Paired samples t-tests assessed any area and volumetric changes of the UA after RME. Changes in degree of nasal obstruction, calculated as the AN ratio, was then compared for the two groups. An independent samples t-test compared volumetric changes in the nasopharynx between the two groups before and after RME. Results Changes in cross-sectional areas and volumes of the UA due to RME were not significant. The effects of RME on AN ratio (11 % vs 0 %) and nasopharyngeal volume (36.8 % vs 5.97%) were somewhat larger in group 2 patients who had adenoid-associated nasal obstruction compared with group 1 patients with a normal-sized adenoid; however, the differences were not significant. Conclusions After RME, the patients with an enlarged adenoid had more increases in nasopharyngeal volume compared with those with normal adenoid, despite there was no significant difference.


Assuntos
Tonsila Faríngea , Técnica de Expansão Palatina , Tonsila Faríngea/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Humanos , Maxila , Nariz/diagnóstico por imagem , Estudos Retrospectivos
4.
Water Sci Technol ; 82(7): 1350-1369, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33079715

RESUMO

A hydrophobically associating cationic polyacrylamide (HACPAM) was prepared by using a micellar polymerization method with V-50 (azobisisobutyramidine hydrochloride) as the initiator and acrylamide, acryloyloxyethyl trimethylammonium chloride and butyl methacrylate as substrates under ultraviolet light irradiation. Structural analysis using Fourier transform infrared spectroscopy, proton nuclear magnetic resonance and X-ray photoelectron spectroscopy analyses showed that the substrates were successfully polymerized. HACPAM was used to condition sludge to improve its dewatering performance, and the results showed that as the amount of HACPAM increases, the sludge dewatering performance is significantly improved, and 3.532 kg/t dry solids of HACPAM is regarded as the optimal amount. Compared with the commercially available cationic polyacrylamide (CPAM), HACPAM has a stronger hydrophobic group association effect, with better promotion of the conversion of bound water in sludge flocs into free water, thereby improving the sewage dewatering performance. The 3D spatial structure of dewatered sludge cakes analyzed by computed tomography technology showed that the number of pores of the dewatered sludge cake treated by HACPAM 3 was smaller than that of the cake treated by CPAM, with a reduction in the porosity of 68.8%, resulting in a better hydrophobic effect. In addition, the mechanism of HACPAM improving the dewatering performance is discussed.


Assuntos
Resinas Acrílicas , Esgotos , Cátions , Polimerização
5.
Drug Dev Ind Pharm ; 42(11): 1833-41, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27080252

RESUMO

The aim of this study was to formulate face-cut, melt-extruded pellets, and to optimize hot melt process parameters to obtain maximized sphericity and hardness by utilizing Soluplus(®) as a polymeric carrier and carbamazepine (CBZ) as a model drug. Thermal gravimetric analysis (TGA) was used to detect thermal stability of CBZ. The Box-Behnken design for response surface methodology was developed using three factors, processing temperature ( °C), feeding rate (%), and screw speed (rpm), which resulted in 17 experimental runs. The influence of these factors on pellet sphericity and mechanical characteristics was assessed and evaluated for each experimental run. Pellets with optimal sphericity and mechanical properties were chosen for further characterization. This included differential scanning calorimetry, drug release, hardness friability index (HFI), flowability, bulk density, tapped density, Carr's index, and fourier transform infrared radiation (FTIR) spectroscopy. TGA data showed no drug degradation upon heating to 190 °C. Hot melt extrusion processing conditions were found to have a significant effect on the pellet shape and hardness profile. Pellets with maximum sphericity and hardness exhibited no crystalline peak after extrusion. The rate of drug release was affected mainly by pellet size, where smaller pellets released the drug faster. All optimized formulations were found to be of superior hardness and not friable. The flow properties of optimized pellets were excellent with high bulk and tapped density.


Assuntos
Carbamazepina/química , Liberação Controlada de Fármacos/efeitos dos fármacos , Polietilenoglicóis/química , Polímeros/química , Estabilidade de Medicamentos , Temperatura Alta , Tamanho da Partícula , Polivinil/química , Espectroscopia de Infravermelho com Transformada de Fourier
6.
AAPS PharmSciTech ; 17(1): 78-88, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26283197

RESUMO

Over the past few decades, nanocrystal formulations have evolved as promising drug delivery systems owing to their ability to enhance the bioavailability and maintain the stability of poorly water-soluble drugs. However, conventional methods of preparing nanocrystal formulations, such as spray drying and freeze drying, have some drawbacks including high cost, time and energy inefficiency, traces of residual solvent, and difficulties in continuous operation. Therefore, new techniques for the production of nanocrystal formulations are necessary. The main objective of this study was to introduce a new technique for the production of nanocrystal solid dispersions (NCSDs) by combining high-pressure homogenization (HPH) and hot-melt extrusion (HME). Efavirenz (EFZ), a Biopharmaceutics Classification System class II drug, which is used for the treatment of human immunodeficiency virus (HIV) type I, was selected as the model drug for this study. A nanosuspension (NS) was first prepared by HPH using sodium lauryl sulfate (SLS) and Kollidon® 30 as a stabilizer system. The NS was then mixed with Soluplus® in the extruder barrel, and the water was removed by evaporation. The decreased particle size and crystalline state of EFZ were confirmed by scanning electron microscopy, zeta particle size analysis, and differential scanning calorimetry. The increased dissolution rate was also determined. EFZ NCSD was found to be highly stable after storage for 6 months. In summary, the conjugation of HPH with HME technology was demonstrated to be a promising novel method for the production of NCSDs.


Assuntos
Química Farmacêutica/métodos , Composição de Medicamentos/métodos , Nanopartículas/química , Alcinos , Benzoxazinas/química , Varredura Diferencial de Calorimetria/métodos , Ciclopropanos , Portadores de Fármacos/química , Estabilidade de Medicamentos , Liofilização/métodos , Temperatura Alta , Tamanho da Partícula , Polietilenoglicóis/química , Polivinil/química , Povidona/química , Solubilidade , Suspensões/química , Água/química
7.
Drug Dev Ind Pharm ; 41(9): 1479-87, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25224341

RESUMO

The recrystallization of an amorphous drug in a solid dispersion system could lead to a loss in the drug solubility and bioavailability. The primary objective of the current research was to use an improved kinetic model to evaluate the recrystallization kinetics of amorphous structures and to further understand the factors influencing the physical stability of amorphous solid dispersions. Amorphous solid dispersions of fenofibrate with different molecular weights of hydroxypropylcellulose, HPC (Klucel™ LF, EF, ELF) were prepared utilizing hot-melt extrusion technology. Differential scanning calorimetry was utilized to quantitatively analyze the extent of recrystallization in the samples stored at different temperatures and relative humidity (RH) conditions. The experimental data were fitted into the improved kinetics model of a modified Avrami equation to calculate the recrystallization rate constants. Klucel LF, the largest molecular weight among the HPCs used, demonstrated the greatest inhibition of fenofibrate recrystallization. Additionally, the recrystallization rate (k) decreased with increasing polymer content, however exponentially increased with higher temperature. Also k increased linearly rather than exponentially over the range of RH studied.


Assuntos
Celulose/análogos & derivados , Fenofibrato/administração & dosagem , Modelos Químicos , Polímeros/química , Varredura Diferencial de Calorimetria , Celulose/química , Química Farmacêutica/métodos , Cristalização , Composição de Medicamentos , Estabilidade de Medicamentos , Fenofibrato/química , Temperatura Alta , Umidade , Cinética , Peso Molecular , Solubilidade , Temperatura
8.
Am J Orthod Dentofacial Orthop ; 147(2): 197-204, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25636553

RESUMO

INTRODUCTION: In this study, we aimed to evaluate the adenoidal nasopharyngeal ratio (ANR) on lateral cephalograms by assessing upper airway volumes using cone-beam computed tomography (CBCT) images as the validation method. METHODS: Fifty-five patients were included in the study, and it was essential that the lateral cephalograms and CBCT images taken at their examinations were not more than 1 week apart. There were 32 subjects in group A (age ≤15 years) and 23 subjects in group B (age >15 years). The ANR was measured on the lateral cephalograms. The area and volumetric measurements of the nasopharynx and the total upper airway were obtained from CBCT images. Repeated measurements of the ANR and airway volume were performed on 10 subjects by 2 observers. RESULTS: Group A had a higher correlation (r = -0.78) between the ANR and the nasopharynx volume than did group B (r = -0.57). The ANR had a weak correlation with the total upper airway volume (group A, r = -0.48; group B, r = -0.32). Both measurements made on lateral cephalograms and CBCT were highly reproducible in terms of intraobserver and interobserver agreement. CONCLUSIONS: Based on our results, the measurement of the ANR on lateral cephalograms can be used as an initial screening method to estimate the nasopharynx volumes of younger patients (age ≤15 years).


Assuntos
Cefalometria/estatística & dados numéricos , Tomografia Computadorizada de Feixe Cônico/estatística & dados numéricos , Nasofaringe/anatomia & histologia , Tonsila Faríngea/anatomia & histologia , Tonsila Faríngea/diagnóstico por imagem , Adolescente , Adulto , Fatores Etários , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Masculino , Nasofaringe/diagnóstico por imagem , Variações Dependentes do Observador , Tamanho do Órgão , Faringe/anatomia & histologia , Faringe/diagnóstico por imagem , Radiografia Dentária Digital/estatística & dados numéricos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
9.
J Biomech ; 168: 112111, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38657433

RESUMO

Snoring is common in children and is associated with many adverse consequences. One must study the relationships between pharyngeal morphology and snoring physics to understand snoring progression. Although some model studies have provided fluid-structure interaction dynamic descriptions for the correlation between airway size and snoring physics, the descriptions still need to be further investigated in patient-specific airway models. Fluid-structure interaction studies using patient-specific airway structures complement the above model studies. Based on reported cephalometric measurement methods, this study quantified and preset the size of the palatopharynx airway in a patient-specific airway and investigated how the palatopharynx size affects the pharyngeal airflow fluctuation, soft palate vibration, and glossopharynx vibration with the help of a verified FSI method. The results showed that the stenosis anterior airway of the soft palate increased airway resistance and airway resistance fluctuations, which can lead to increased sleep effort and frequent snoring. Widening of the anterior airway can reduce airflow resistance and avoid obstructing the anterior airway by the soft palate vibration. The pharyngeal airflow resistance, mouth inflow proportion, and soft palate apex displacement have components at the same frequencies in all airway models, and the glossopharynx vibration and instantaneous inflow rate have components at the same frequencies, too. The mechanism of this same frequency fluctuation phenomenon can be explained by the fluid-structure interaction dynamics of an ideal coupled model consisting of a flexible plate model and a collapsible tube model. The results of this study demonstrate the potential of FSI in studying snoring physics and clarify to some degree the mechanism of airway morphology affecting airway vibration physics.


Assuntos
Palato Mole , Faringe , Ronco , Vibração , Humanos , Faringe/fisiologia , Ronco/fisiopatologia , Criança , Palato Mole/fisiologia , Palato Mole/fisiopatologia , Masculino , Resistência das Vias Respiratórias/fisiologia , Modelos Biológicos
10.
Int J Biol Macromol ; 278(Pt 4): 134752, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39214837

RESUMO

Three-dimensional bioprinting leverages computer-aided design to construct tissues and organs with specialized bioinks. A notable biomaterial for this purpose is chitosan, a natural polysaccharide sourced from crustacean exoskeletons. Chitosan's biocompatibility, biodegradability, non-toxicity, and ability to promote cell adhesion and proliferation make it an excellent component for bioinks. Initially, the rheological properties of chitosan presented challenges for its use in bioprinting. Enhancements in its printability and stability were achieved by integrating it with other natural or synthetic polymers, facilitating its successful application in bioprinting. Chitosan-based bioinks are particularly promising for controlled drug delivery. Incorporating pharmaceuticals directly into the bioink enables the printed structures to serve as localized, sustained-release systems. This approach offers multiple advantages, including precise drug delivery to targeted disease sites, increased therapeutic efficiency, and reduced systemic side effects. Moreover, bioprinting allows for the customization of drug delivery mechanisms to meet individual patient requirements. Although there have been considerable advancements, the use of chitosan-based bioinks in drug delivery is still an emerging field. This review highlights chitosan's essential role in both systemic and localized drug delivery, underscoring its significance and discussing ongoing trends in its application for pharmaceutical purposes.


Assuntos
Bioimpressão , Quitosana , Sistemas de Liberação de Medicamentos , Impressão Tridimensional , Quitosana/química , Bioimpressão/métodos , Humanos , Materiais Biocompatíveis/química , Animais , Tinta , Engenharia Tecidual/métodos
11.
Int J Biol Macromol ; 265(Pt 2): 130795, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38492696

RESUMO

The utilization of biomass-based conductive polymer hydrogels in wearable electronics holds great promise for advancing performance and sustainability. An interpenetrating network of polyacrylamide/2-hydroxypropyltrimethyl ammonium chloride chitosan (PAM/HACC) was firstly obtained through thermal-initiation polymerization of AM monomers in the presence of HACC. The positively charged groups on HACC provide strong electrostatic interactions and hydrogen bonding with the PAM polymer chains, leading to improved mechanical strength and stability of the hydrogel network. Subsequently, the PAM/HACC networks served as the skeletons for the in-situ polymerization of polypyrrole (PPy), and then the resulting conductive hydrogel demonstrated stable electromagnetic shielding performance (40 dB), high sensitivity for strain sensing (gauge factor = 2.56). Moreover, the incorporation of quaternary ammonium chitosan into PAM hydrogels enhances their antimicrobial activity, making them more suitable for applications in bacterial contamination or low-temperature environments. This conductive hydrogel, with its versatility and excellent mechanical properties, shows great potential in applications such as electronic skin and flexible/wearable electronics.


Assuntos
Resinas Acrílicas , Compostos de Amônio , Quitosana/análogos & derivados , Compostos de Amônio Quaternário , Polímeros , Pirróis , Antibacterianos/farmacologia , Condutividade Elétrica , Hidrogéis
12.
Toxicol In Vitro ; 97: 105793, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38401745

RESUMO

To combat opioid abuse, the U.S. Food and Drug Administration (FDA) released a comprehensive action plan to address opioid addiction, abuse, and overdose that included increasing the prevalence of abuse-deterrent formulations (ADFs) in opioid tablets. Polyethylene oxide (PEO) has been widely used as an excipient to deter abuse via nasal insufflation. However, changes in abuse patterns have led to unexpected shifts in abuse from the nasal route to intravenous injection. Case reports identify adverse effects similar to thrombotic thrombocytopenic purpura (TTP) syndrome following the intravenous (IV) abuse of opioids containing PEO excipient. Increased risk of IV opioid ADF abuse compared to clinical benefit of the drug led to the removal of one opioid product from the market in 2017. Because many generic drugs containing PEO are still in development, there is interest in assessing safety consistent with generic drug regulation and unintended uses. Currently, there are no guidelines or in vitro assessment tools to characterize the safety of PEO excipients taken via intravenous injection. To create a more robust excipient safety evaluation tool and to study the mechanistic basis of HMW PEO-induced TMA, a dynamic in vitro test system involving blood flow through a needle model has been developed.


Assuntos
Analgésicos Opioides , Transtornos Relacionados ao Uso de Opioides , Humanos , Polietilenoglicóis/toxicidade , Polímeros , Peso Molecular , Excipientes , Técnicas In Vitro
13.
Anal Chim Acta ; 1309: 342699, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38772652

RESUMO

Extracellular vesicles (EVs) are cell-released, nucleus-free particles with a double-membrane structure that effectively prevents degradation of internal components by a variety of salivary enzymes. Saliva is an easily accessible biofluid that contains a wealth of valuable information for disease diagnosis and monitoring and especially reflect respiratory and digestive tract diseases. However, the lack of efficient and high-throughput methods for proteomic analysis of salivary biomarkers poses a significant challenge. Herein, we designed a salivary EV amphiphile-dendrimer supramolecular probe (SEASP) array which enables efficient enrichment and in situ detection of EVs protein biomarkers. Detergent Tween-20 washing of SEASP arrays removes high abundance of heteroproteins from saliva well. This array shows good analytical performance in the linear range of 10 µL-150 µL (LOD = 0.4 µg protein, or 10 µL saliva), exhibiting a good recovery (80.0 %). Compared to ultracentrifugation (UC), this procedure provides simple and convenient access to high-purity EVs (1.3 × 109 particles per mg protein) with good physiological status and structure. Coupling with mass spectrometry based proteomic analysis, differentially expressed proteins as selected asthma biomarkers have been screened. Then, we validated the proteomics primary screening results through clinical samples (100 µL each) using the SEASP array. Utilizing the dual antibody fluorescence technology, SEASP enables the simultaneous high-throughput detection of two proteins. Therefore, the EVs marker protein CD81 could be used as an internal standard to normalize the number of EVs, which was stably expressed in EVs. Proteomics and array results suggested that HNRNPU (P = 4.9 * 10-6) and MUC5B (P = 4.7 * 10-11) are promising protein biomarkers for infantile asthma. HNRNPU and MUC5B may be associated with disease onset and subtypes. The SEASP arrays provide a significant advancement in the field of salivary biomarker. The array enables high-throughput in situ protein detection for highly viscous and complex biological samples. It provides a rapid, low-cost, highly specific screening procedure and experimental basis for early disease screening and diagnosis in the field of liquid biopsy.


Assuntos
Vesículas Extracelulares , Proteômica , Saliva , Saliva/química , Humanos , Vesículas Extracelulares/química , Vesículas Extracelulares/metabolismo , Proteômica/métodos , Biomarcadores/análise , Ensaios de Triagem em Larga Escala , Asma/diagnóstico , Asma/metabolismo
14.
Cell Biosci ; 13(1): 75, 2023 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-37088831

RESUMO

BACKGROUND: Mutations in the signal transducers and activators of transcription 3 (STAT3) gene result in hyper-IgE syndrome(HIES), a rare immunodeficiency that causes abnormalities in immune system, bones and teeth. However, the role of Stat3 in development of dental hard tissues was yet to investigate. METHODS: In this study, a transgenic mouse of conditional knockout of Stat3 in dental mesenchymal cells (Osx-Cre; Stat3fl/fl, Stat3 CKO) was made. The differences of postnatal tooth development between control and Stat3 CKO mice were compared by histology, µCT and scanning electron microscopy. RESULT: Compared with the control, Stat3 CKO mice were presented with remarkable abnormal tooth phenotypes characterized by short root and thin dentin in molars and incisors. The enamel defects were also found on mandibular incisors. showed that Ki67-positive cells significantly decreased in dental mesenchymal of Stat3 CKO mice. In addition, ß-catenin signaling was reduced in Hertwig's epithelial root sheath (HERS) and odontoblasts of Stat3 CKO mice. CONCLUSIONS: Our results suggested that Stat3 played an important role in dental hard tissues development, and Stat3 may regulate dentin and tooth root development through the ß-catenin signaling pathway.

15.
Food Chem ; 413: 135653, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36773361

RESUMO

The Pickering emulsion may be restricted in the foods owing to the unreasonable use of oils. Herein, the effect of different oil phases on the stability of myofibrillar protein microgel particles stabilized Pickering emulsions was investigated. Results showed sunflower oil Pickering emulsions with high stability have the smallest droplet size (-26.17 µm). While peanut oil Pickering emulsions have the largest droplet size (-77.00 µm) and poor emulsion stability. The fatty acid analysis showed sunflower oil had low content of saturated (15.68 %) and super-long-chain (0) fatty acids, while peanut oil had high content of saturated (23.67 %) and super-long-chain (9.02 %) fatty acids, leading to a difference in viscosity. Low viscosity was more conducive to dispersing oil droplets and inhibiting the floating and gathering of droplets, thus enhancing the emulsion stability. Therefore, the oil with low content of super-long-chain and saturated fatty acids could be suitable for preparing MMP Pickering emulsions.


Assuntos
Microgéis , Óleo de Girassol , Óleo de Amendoim , Emulsões , Viscosidade , Ácidos Graxos , Tamanho da Partícula , Água
16.
Sci Rep ; 13(1): 2013, 2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36737491

RESUMO

The uvula flapping is one of the most distinctive features of snoring and is critical in affecting airway aerodynamics and vibrations. This study aimed to elucidate the mechanism of pharyngeal vibration and pressure fluctuation due to uvula flapping employing fluid-structure interaction simulations. The followings are the methodology part: we constructed an anatomically accurate pediatric pharynx model and put attention on the oropharynx region where the greatest level of upper airway compliance was reported to occur. The uvula was assumed to be a rigid body with specific flapping frequencies to guarantee proper boundary conditions with as little complexity as possible. The airway tissue was considered to have a uniform thickness. It was found that the flapping frequency had a more significant effect on the airway vibration than the flapping amplitude, as the flapping uvula influenced the pharyngeal aerodynamics by altering the jet flow from the mouth. Breathing only through the mouth could amplify the effect of flapping uvula on aerodynamic changes and result in more significant oropharynx vibration.


Assuntos
Faringe , Úvula , Humanos , Criança , Vibração , Ronco , Orofaringe
17.
J Chromatogr A ; 1705: 464186, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37453175

RESUMO

High molar mass polyethylene oxide (HM-PEO) is commonly used to enhance the mechanical strength of solid oral opioid drug products to deter abuse. Because the properties of PEO depend on molar mass distribution, accurately determining the molar mass distribution is a necessary part of understanding PEO's role in abuse-deterrent formulations (ADF). In this study, an asymmetrical flow field-flow fractionation (AF4) analytical procedure was developed to characterize PEO polymers with nominal molar masses of 1, 4 or 7 MDa as well as those from in-house prepared placebo ADF. The placebo ADF were manufactured using direct compress or hot-melt-extrusion methods, and subjected to physical manipulation, such as heating and grinding before measurement by AF4 were performed. The molar mass distribution characterized by AF4 revealed that PEO was sensitive to thermal stress, exhibiting decreased molar mass with increased heat exposure. The optimized AF4 method was deemed suitable for characterizing HM-PEO, offering adequate dynamic separation range for PEO with molar mass from 100 kDa to approximately 10 MDa.


Assuntos
Formulações de Dissuasão de Abuso , Fracionamento por Campo e Fluxo , Polietilenoglicóis , Fracionamento por Campo e Fluxo/métodos , Comprimidos , Composição de Medicamentos
18.
Food Chem ; 419: 136044, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37011570

RESUMO

The regulation mechanism of ionic strength (0-1000 mM) on the freeze-thaw (FT) stability of emulsions stabilized by myofibrillar protein microgel particles (MMP) was systematically investigated. High ionic strength emulsions (300-1000 mM) exhibited stability after five FT cycles. With ionic strength increasing, the repulsive force between particles gradually reduced, the flocculation degree (20.72 âˆ¼ 75.60%) and apparent viscosity of emulsions gradually rose (69 âˆ¼ 170 mPa·s), promoting the formation of protein network structures in the continuous phase. Concurrently, the interfacial proteins rearranged (18.8 âˆ¼ 104.2 s-1) and aggregated rapidly, facilitating the formation of a stable interface network structure, ultimately improving its stability. Besides, scanning electron microscopy (SEM) images revealed that the interfacial proteins gradually aggregated, further forming a network with the MMP in the continuous phase, allowing MMP emulsions with enhanced FT stability at high ionic strength (300-1000 mM). This study was beneficial to produce emulsion-based sauces with ultra-high FT stability.


Assuntos
Microgéis , Emulsões/química , Congelamento , Concentração Osmolar , Microscopia Eletrônica de Varredura
19.
J Biomech ; 152: 111550, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36996600

RESUMO

Snoring is a common condition in the general population, and the management of snoring requires a better understanding of its mechanism through a fluid-structure interaction (FSI) perspective. Despite the recent popularity of numerical FSI techniques, outstanding challenges are accurately predicting airway deformation and its vibration during snoring due to complex airway morphology. In addition, there still needs to be more understanding of snoring inhibition when lying on the side, and the possible effect of airflow rates, as well as nose or mouth-nose breathing, on snoring remains to be investigated. In this study, an FSI method verified against in vitro models was introduced to predict upper airway deformation and vibration. The technique was applied to predict airway aerodynamics, soft palate flutter, and airway vibration in four sleep postures (supine, left/right lying, and sitting positions) and four breathing patterns (mouth-nose, nose, mouth, and unilateral nose breathing). It was found that, at given elastic properties of soft tissues, the evaluated flutter frequency of 19.8 Hz in inspiration was in good agreement with the reported frequency of snoring sound in literature. Reduction in flutter and vibrations due to the mouth-nose airflow proportion changes were also noticed when having side-lying and sitting positions. Breathing through the mouth results in larger airway deformation than breathing through the nose or mouth-nose. These results collectively demonstrate the potential of FSI for studying the physics of airway vibration and clarify to some degree the reason for snoring inhibition during sleep postures and breathing patterns.


Assuntos
Faringe , Apneia Obstrutiva do Sono , Humanos , Criança , Ronco , Vibração , Sono/fisiologia , Palato Mole , Respiração , Postura
20.
J Vis Exp ; (202)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38189367

RESUMO

Varicoceles are dilated veins within the pampiniform plexus and are relatively common in the general male population. The spermatic vein has many branches in the scrotal segment and then gradually merges into 1-2 trunks after passing through the internal inguinal ring. The key to a successful varicocelectomy is to ligate all the spermatic veins while protecting the testicular arteries and spermatic lymphatic vessels from damage. The small veins, including the branches of spermatic veins and collateral veins, are easily missed for ligation during conventional high ligation of varicocele, which has been suggested as a major cause of postoperative recurrence. Although microsurgery effectively reduces the risk of missing ligation of the spermatic veins during surgery, it has several shortcomings, such as long operation time and a steep learning curve. More importantly, this technique is difficult to carry out in primary hospitals due to the requirement of specialized equipment. Therefore, an attempt to modify the traditional high ligation aiming to reduce the postoperative recurrence rate has been carried out here. The protocol here combines traditional high ligation with intraoperative embolization to seal off the branches of the spermatic vein and collateral veins. We rapidly injected foamed sclerosant into the internal spermatic vein under direct observation after separation of the spermatic vein and then ligated all the veins. The foamed sclerosant through the varicose vein hampers endothelial cell growth, promotes the growth of thrombus and fibrosis, and ultimately forms fibrous streaks that permanently fill the venous. The results showed a more satisfactory effect on reducing the postoperative recurrence rate compared with traditional high ligation. Since this protocol is simple to carry out and has better results in reducing the recurrence rate, this can be an alternative surgical method for the treatment of varicocele, especially in primary hospitals.


Assuntos
Embolização Terapêutica , Varicocele , Masculino , Humanos , Varicocele/cirurgia , Polidocanol , Soluções Esclerosantes , Veias
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