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1.
Int J Biol Macromol ; 270(Pt 1): 132178, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38735614

RESUMEN

In response to escalating environmental concerns and the urgent need for sustainable drug delivery systems, this study introduces biodegradable pH-responsive microcapsules synthesized from a blend of gelatin, alginate, and hyaluronic acid. Employing the coacervation process, capsules were created with a spherical shape, multicore structure, and small sizes ranging from 10 to 20 µm, which exhibit outstanding vitamin E encapsulation efficiency. With substantial incorporation of hyaluronic acid, a pH-responsive component, the resulting microcapsules displayed noteworthy swelling behavior, facilitating proficient core ingredient release at pH 5.5 and 7.4. Notably, these capsules can effectively deliver active substances to the dermal layer under specific skin conditions, revealing promising applications in topical medications and cosmetics. Furthermore, the readily biodegradable nature of the designed capsules was demonstrated through Biochemical Oxygen Demand (BOD) testing, with over 80 % of microcapsules being degraded by microorganisms after one week of incubation. This research contributes to the development of responsive microcapsules and aligns with broader environmental initiatives, offering a promising pathway to mitigate the impact of microplastics while advancing various applications.

2.
Polymers (Basel) ; 16(7)2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38611246

RESUMEN

Currently, metal is the most common exterior material used in robot development due to the need to protect the motor. However, as soft, wearable, and humanoid robots are gradually being developed, many robot parts need to be converted into artificial skin using flexible materials. In this study, in order to develop soft exterior parts for robots, we intended to manufacture exterior robot arm parts via fused filament fabrication (FFF) 3D printing according to various structural and thickness conditions and analyze their mechanical properties. The exterior parts of the robot arms were manufactured utilizing Shore 95 A TPU (eTPU, Esun, Shenzhen, China), which is renowned for its softness and exceptional shock absorption characteristics. The exterior robot arm parts were modeled in two parts, the forearm and upper arm, by applying solid (SL) and re-entrant (RE) structures and thicknesses of 1, 2, and 4 mm. The mechanical properties were analyzed through the use of three-point bending, tensile, and compression testing. All of the characterizations were analyzed using a universal testing machine (AGS-X, SHIMADZU, Kyoto, Japan). After testing the samples, it was confirmed that the RE structure was easily bendable towards the bending curve and required less stress. In terms of the tensile tests, the results were similar to the bending tests; to achieve the maximum point, less stress was required, and for the compression tests, the RE structure was able to withstand the load compared to the SL structure. Therefore, after analyzing all three thicknesses, it was confirmed that the RE structure with a 2 mm thickness had excellent characteristics in terms of bending, tensile, and compressive properties. Therefore, the re-entrant pattern with a 2 mm thickness is more suitable for manufacturing a 3D-printed humanoid robot arm.

3.
Front Psychol ; 14: 1117369, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36844301

RESUMEN

Objective: The unprecedented coronavirus disease 2019 (COVID-19) outbreak has resulted in a global crisis that negatively impacted physical well-being and mental health. Our goal was to investigate the impact of the COVID-19 pandemic on health-related quality of life (HRQoL) and depressive symptoms in patients with chronic diseases and the general population in Korea. Methods: Data from 8341 patients with chronic diseases and 12,395 general population aged ≥20 years who participated in the Korea National Health and Nutrition Examination Survey (2017-2020) were analyzed. Patients with hypertension, dyslipidemia, diabetes, cerebrovascular disease (stroke), heart disease (myocardial infarction or angina pectoris), or cancer were classified as patients with chronic diseases. The general population was defined as those not suffering from corresponding chronic diseases. A modified EuroQol-5 Dimensions (EQ-5D), with three levels (0: extreme problems; 0.5: some problems; 1: no problems) for each dimension in EQ-5D, was used to assess HRQoL. To analyze depressive symptoms among patients with chronic diseases and the general population, we used the Patient Health Questionnaire-9 (PHQ-9) and defined a PHQ-9 score ≥ 10 as having a depressive symptom. Multivariate linear and logistic regression analyses were used to analyze HRQoL and depressive symptoms before and during the COVID-19 pandemic. Results: The HRQoL level was significantly lower in patients with chronic diseases compared to the general population on all dimensions both before and during the COVID-19 pandemic (all value of p < 0.05). Patients with chronic diseases had significantly lower HRQoL levels associated with the anxiety/depression dimension during the COVID-19 pandemic than in the pre-pandemic period (0.940 ± 0.002 vs. 0.929 ± 0.004, value of p = 0.041). In addition, patients with chronic diseases were more likely to report depressive symptoms during the COVID-19 pandemic than in the pre-pandemic period (Odds ratio (OR): 1.755, 95% confidence interval (CI): 1.209-2.546, value of p = 0.003). However, this association was not observed in the general population (OR: 1.275, 95% CI: 0.933-1.742, value of p = 0.13). Conclusion: The COVID-19 pandemic affected the HRQoL and psychological health in patients with chronic diseases with higher anxiety/depression during the pandemic than in the pre-pandemic period. These results suggest that it is urgent to establish continuous management guidelines, including psychosocial management for high-risk groups, and to improve the existing healthcare system.

4.
Carbohydr Polym ; 304: 120490, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36641177

RESUMEN

With an increase in the severity of environmental pollution caused by microbeads, the development of biodegradable microcapsules that can be applied in diverse fields has attracted significant attention. The degradation processes are directly related to biodegradable microcapsule creation with high stability and persistence. In this study, biodegradable microcapsules are synthesized via a complex coacervation approach using gelatin and alginate as the capsule main wall materials; additionally, enzyme-induced decomposition mechanisms are proposed by observing spectral changes in proton nuclear magnetic resonance (1H NMR) analyses. Additional analytical techniques confirm the chemical structure, morphology, and size distribution of the synthesized capsules; these uniform spherical microcapsules are 20-30 µm in size and possess a smooth surface. In addition to characterization, the microcapsules were exposed to targeted enzymes to investigate enzymatic effects using short-term and long-term degradation kinetics. Close inspection reveals that determination of the degradation rate constant of the major components in the capsule is feasible, and suggests two types of 4-stage degradation mechanisms that are enzyme-specific. These investigations demonstrate that capsule degradation can be explored in detail using 1H NMR spectroscopy to provide a viable strategy for monitoring degradation properties in the development of new biodegradable polymers.


Asunto(s)
Alginatos , Gelatina , Cápsulas/química , Alginatos/química , Cinética , Espectroscopía de Resonancia Magnética
5.
J Korean Med Sci ; 37(43): e316, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36345258

RESUMEN

BACKGROUND: Patient education is generally accompanied by instructive materials. The Korean government has recommended the provision of patient-specific educational materials (PEMs) via an electronic medical record (EMR) certification system. However, there are currently no clear standards or guidelines for including PEMs in current domestic educational materials. We investigated the benefits of integrating PEMs with the EMR certification system and the methods by which this integration can be achieved. METHODS: We developed and administered three structured Delphi surveys to 26 healthcare providers in clinical settings based on data collected from separate semi-structured advisory interviews with five experts. The surveys included the following topics: 1) expected effects of patient-specific education and health-related notifications/alarms, 2) desirable methods for providing PEMs, and 3) appropriate fee-setting and government support. We distributed the Delphi surveys via e-mail and calculated the average and standard deviation of the survey responses. RESULTS: PEMs are expected to have significant educational effects, such as the provision of surgery/intervention-related information, and will improve the understanding of various treatment processes/procedures. The preferred method for providing PEMs was via automatic request after receiving confirmation from healthcare providers. The provision of these materials was based on set fees and government support. The average fee per session was set at approximately USD 23 (as of October 2021, USD 1 = KRW 1,196). CONCLUSION: In this study, we investigated the prerequisites, contents, methods, and fees related to the provision of effective and efficient PEMs. The study findings can facilitate the production and provision of PEMs.


Asunto(s)
Personal de Salud , Humanos , Escolaridad
6.
Viruses ; 14(2)2022 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-35216039

RESUMEN

Coinfection rates with other pathogens in coronavirus disease 2019 (COVID-19) varied during the pandemic. We assessed the latest prevalence of coinfection with viruses, bacteria, and fungi in COVID-19 patients for more than one year and its impact on mortality. A total of 436 samples were collected between August 2020 and October 2021. Multiplex real-time PCR, culture, and antimicrobial susceptibility testing were performed to detect pathogens. The coinfection rate of respiratory viruses in COVID-19 patients was 1.4%. Meanwhile, the rates of bacteria and fungi were 52.6% and 10.5% in hospitalized COVID-19 patients, respectively. Respiratory syncytial virus, rhinovirus, Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans were the most commonly detected pathogens. Ninety percent of isolated A. baumannii was non-susceptible to carbapenem. Based on a multivariate analysis, coinfection (odds ratio [OR] = 6.095), older age (OR = 1.089), and elevated lactate dehydrogenase (OR = 1.006) were risk factors for mortality as a critical outcome. In particular, coinfection with bacteria (OR = 11.250), resistant pathogens (OR = 11.667), and infection with multiple pathogens (OR = 10.667) were significantly related to death. Screening and monitoring of coinfection in COVID-19 patients, especially for hospitalized patients during the pandemic, are beneficial for better management and survival.


Asunto(s)
Infecciones Bacterianas/epidemiología , COVID-19/epidemiología , Coinfección/microbiología , Coinfección/virología , Micosis/epidemiología , Virosis/epidemiología , Adolescente , Adulto , Bacterias/clasificación , Bacterias/patogenicidad , COVID-19/microbiología , COVID-19/virología , Coinfección/epidemiología , Coinfección/mortalidad , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Infección Hospitalaria/virología , Femenino , Hongos/clasificación , Hongos/patogenicidad , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , República de Corea/epidemiología , Virus/clasificación , Virus/patogenicidad , Adulto Joven
7.
Viruses ; 13(10)2021 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-34696519

RESUMEN

This study investigated the infectivity of severe acute respiratory syndrome (SARS-CoV-2) in individuals who re-tested positive for SARS-CoV-2 RNA after recovering from their primary illness. We investigated 295 individuals with re-positive SARS-CoV-2 polymerase chain reaction (PCR) test results and 836 of their close contacts. We attempted virus isolation in individuals with re-positive SARS-CoV-2 PCR test results using cell culture and confirmed the presence of neutralizing antibodies using serological tests. Viral culture was negative in all 108 individuals with re-positive SARS-CoV-2 PCR test results in whom viral culture was performed. Three new cases of SARS-CoV-2 infection were identified among household contacts using PCR. Two of the three new cases had had contact with the index patient during their primary illness, and all three had antibody evidence of past infection. Thus, there was no laboratory evidence of viral shedding and no epidemiological evidence of transmission among individuals with re-positive SARS-CoV-2 PCR test results.


Asunto(s)
Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , COVID-19/inmunología , Reinfección/virología , SARS-CoV-2/inmunología , Esparcimiento de Virus/fisiología , Adolescente , Adulto , Anciano , COVID-19/diagnóstico , COVID-19/transmisión , Prueba Serológica para COVID-19 , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Reinfección/inmunología , República de Corea , Estudios Retrospectivos , SARS-CoV-2/aislamiento & purificación , Índice de Severidad de la Enfermedad , Adulto Joven
8.
Genes Nutr ; 15(1): 6, 2020 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-32293245

RESUMEN

BACKGROUND: The premature activation of digestive enzyme zymogens within pancreatic acinar cells is an important early feature of acute pancreatitis. Supraphysiological concentrations of cholecystokinin (CCK) cause intrapancreatic zymogen activation and acute pancreatitis. Stimulation of vacuolar ATPase (vATPase) activity is required for zymogen activation in pancreatic acinar cells. Parkin, a multiprotein E3 ubiquitin ligase complex, promotes vATPase ubiquitination and degradation, which inhibits vATPase activity. Docosahexaenoic acid (DHA), an omega-3 fatty acid, exerts anti-inflammatory effects. It is reported to bind to G-protein coupled receptor 120 (GPR120) and GPR40. DHA induces the degradation of certain proteins by activating ubiquitin-proteasome system in various cells. This study aimed to investigate whether DHA induces Parkin and inhibits vATPase activity, resulting in zymogen inactivation in pancreatic acinar AR42J cells stimulated with cerulein, a CCK analog. RESULTS: Cerulein induced the translocation of the cytosolic V1 domain (E subunit) of vATPase to the membrane, which indicated vATPase activation, and zymogen activation in AR42J cells. DHA suppressed the association of the vATPase with membranes, and zymogen activation (increased trypsin activity and amylase release) induced by cerulein. Pretreatment with a GPR120 antagonist AH-7614, a GPR40 antagonist DC260126, or an ubiquitination inhibitor PYR-41 reduced the effect of DHA on cerulein-induced zymogen activation. Treatment with PYR-41 reversed the DHA-induced decrease in vATPase activation in cerulein-treated cells. Furthermore, DHA increased the level of Parkin in membranes of cerulein-treated cells. CONCLUSIONS: DHA upregulates Parkin which inhibits vATPase-mediated zymogen activation, via GPR120 and GPR40, in cerulein-stimulated pancreatic acinar cells.

9.
Nutrients ; 11(7)2019 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-31248019

RESUMEN

Intracellular Ca2+ homeostasis is commonly disrupted in acute pancreatitis. Sustained Ca2+ release from internal stores in pancreatic acinar cells (PACs), mediated by inositol triphosphate receptor (IP3R) and the ryanodine receptor (RyR), plays a key role in the initiation and propagation of acute pancreatitis. Pancreatitis induced by cerulein, an analogue of cholecystokinin, causes premature activation of digestive enzymes and enhanced accumulation of cytokines and Ca2+ in the pancreas and, as such, it is a good model of acute pancreatitis. High concentrations of the omega-3 fatty acid docosahexaenoic acid (DHA) inhibit inflammatory signaling pathways and cytokine expression in PACs treated with cerulein. In the present study, we determined the effect of DHA on key regulators of Ca2+ signaling in cerulein-treated pancreatic acinar AR42 J cells. The results of RNA-Sequencing (RNA-Seq) analysis showed that cerulein up-regulates the expression of IP3R1 and RyR2 genes, and that pretreatment with DHA blocks these effects. The results of real-time PCR confirmed that DHA inhibits cerulein-induced IP3R1 and RyR2 gene expression, and demonstrated that DHA pre-treatment decreases the expression of the Relb gene, which encodes a component of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) transcriptional activator complex, and the c-fos gene, which encodes a component of activator protein-1 (AP-1) transcriptional activator complex. Taken together, DHA inhibits mRNA expression of IP3R1, RyR2, Relb, and c-fos, which is related to Ca2+ network in cerulein-stimulated PACs.


Asunto(s)
Células Acinares/efectos de los fármacos , Señalización del Calcio/efectos de los fármacos , Ceruletida/toxicidad , Ácidos Docosahexaenoicos/farmacología , Perfilación de la Expresión Génica/métodos , Páncreas Exocrino/efectos de los fármacos , Pancreatitis/tratamiento farmacológico , Análisis de Secuencia de ARN , Células Acinares/metabolismo , Animales , Señalización del Calcio/genética , Línea Celular , Regulación de la Expresión Génica , Receptores de Inositol 1,4,5-Trifosfato/genética , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Páncreas Exocrino/metabolismo , Pancreatitis/inducido químicamente , Pancreatitis/genética , Pancreatitis/metabolismo , Proteínas Proto-Oncogénicas c-fos/genética , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Canal Liberador de Calcio Receptor de Rianodina/genética , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Factor de Transcripción ReIB/genética , Factor de Transcripción ReIB/metabolismo
10.
Bioorg Chem ; 80: 57-63, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29874630

RESUMEN

An effective screening method for inhibitors of NO production in natural products using LC-QTOF MS/MS coupled with a cell-based assay was proposed. The ethyl acetate fraction of Catalpa ovata exhibited a strong inhibitory effect on NO production in lipopolysaccharide-induced BV2 microglia cells. We attempted to identify the active constituents of C. ovata by using LC-QTOF MS/MS coupled with a cell-based assay. Peaks at approximately 14-15 min on the MS chromatogram were estimated to be the bioactive constituents. A new iridoid compound, 6-O-trans-feruloyl-3ß-hydroxy-7-deoxyrehamaglutin A (4), and nine known compounds (1-3, 5-10) were isolated from the ethyl acetate fraction of C. ovata by repeated column chromatography. Compounds 3, 4, 5, 7, and 8 significantly attenuated lipopolysaccharide-stimulated NO production in BV2 cells. Our results indicate that LC-QTOF MS/MS coupled with a cell-based NO production inhibitory assay successfully predicted active compounds without a time-consuming isolation process.


Asunto(s)
Bignoniaceae/química , Productos Biológicos/química , Espectrometría de Masas en Tándem , Animales , Bignoniaceae/metabolismo , Productos Biológicos/aislamiento & purificación , Productos Biológicos/farmacología , Línea Celular , Cromatografía Líquida de Alta Presión , Lipopolisacáridos/farmacología , Espectroscopía de Resonancia Magnética , Ratones , Microglía/citología , Microglía/efectos de los fármacos , Microglía/metabolismo , Conformación Molecular , Óxido Nítrico/metabolismo , Extractos Vegetales/química
11.
Biosci Biotechnol Biochem ; 82(1): 15-21, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29297257

RESUMEN

Our primary focus in this research was to identify and characterize its bioactive compounds for potential therapeutic use. Twenty-seven metabolites of Polygonum orientale were identified using LC-QTOF tandem mass spectrometry. Interestingly, P. orientale extracts included several highly oxygenated flavonoids were isolated from P. orientale by column chromatography. 13C NMR data of highly oxygenated flavonoids (1-7) are reported here for the first time. In addition, nitric oxide, 1,1-diphenyl-2-picrylhydrazyl, and water-soluble tetrazolium salt assays were carried out on the isolated compounds to investigate their anti-inflammatory, anti-oxidant, and neuroprotective activities, respectively. Compounds 1, 2, 3, 5, 7, and 8 significantly attenuated lipopolysaccharide-stimulated NO production in BV2 cells without affecting cell viability. Compounds 9-12 exhibited significant antioxidant activity, while compounds 8, 9, and 12 exhibited protective effects against glutamate-induced neurotoxicity in HT22 cells. Our results indicate that P. orientale is a promising source of natural agents for the potential treatment of inflammation and neurodegenerative diseases.


Asunto(s)
Medicamentos Herbarios Chinos/química , Polygonum/química , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Línea Celular Tumoral , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/farmacología , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/farmacología , Espectrometría de Masas en Tándem/métodos
12.
Bioorg Med Chem Lett ; 27(20): 4710-4713, 2017 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-28927768

RESUMEN

Thymic stromal lymphopoietin (TSLP) is a type II cytokine which is associated with most inflammatory allergic disorders in humans. It is produced mainly by epithelial cells with important role in the development of chronic inflammatory diseases by activating T-helper cell type-2 (TH2) pathways. In this study, a total of 16 peptides were prepared by solid phase peptide synthesis based on amino acid sequences of the interface between TSLP and TSLP receptor. Their TSLP inhibition activities were determined by ELISA assay. Among them, three peptides (6-8) exhibited >50% inhibition at concentration of 0.3mM. They can be used as hit compounds for developing peptide-based TSLP inhibitors.


Asunto(s)
Citocinas/antagonistas & inhibidores , Péptidos/metabolismo , Secuencia de Aminoácidos , Citocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Humanos , Ligandos , Péptidos/química , Unión Proteica , Receptores de Citocinas/química , Receptores de Citocinas/metabolismo , Células Th2/citología , Células Th2/metabolismo , Linfopoyetina del Estroma Tímico
14.
J Nanosci Nanotechnol ; 16(6): 5798-803, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27427634

RESUMEN

Heterogeneous core/shell nanoparticles are currently of great interest for use as an effective way of hydrogen production from storage materials such as methanol, ethanol, and formic acid. Of various fabrication methods, overgrowth of the secondary metal component on a seed material is one of the most commonly used synthetic methods. However, controlling the mode of overgrowth for a deposited metal is nontrivial and remains challenging. We describe here that utilizing a surface ligand for the growth of the secondary metal component on Ag core can dramatically affect the growth mode of the second metal materials. TEM results showed that the presence of a surface ligand enabled the growth mode of the secondary growing component (Au, Pt, or Pd) on Ag nanoparticles to change from island growth to layered growth, making it possible to synthesize precisely well-controlled core/shell nanoparticle structure.

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