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1.
Nature ; 610(7931): 389-393, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36198791

RESUMEN

Directed evolution is a powerful tool for improving existing properties and imparting completely new functionalities to proteins1-4. Nonetheless, its potential in even small proteins is inherently limited by the astronomical number of possible amino acid sequences. Sampling the complete sequence space of a 100-residue protein would require testing of 20100 combinations, which is beyond any existing experimental approach. In practice, selective modification of relatively few residues is sufficient for efficient improvement, functional enhancement and repurposing of existing proteins5. Moreover, computational methods have been developed to predict the locations and, in certain cases, identities of potentially productive mutations6-9. Importantly, all current approaches for prediction of hot spots and productive mutations rely heavily on structural information and/or bioinformatics, which is not always available for proteins of interest. Moreover, they offer a limited ability to identify beneficial mutations far from the active site, even though such changes may markedly improve the catalytic properties of an enzyme10. Machine learning methods have recently showed promise in predicting productive mutations11, but they frequently require large, high-quality training datasets, which are difficult to obtain in directed evolution experiments. Here we show that mutagenic hot spots in enzymes can be identified using NMR spectroscopy. In a proof-of-concept study, we converted myoglobin, a non-enzymatic oxygen storage protein, into a highly efficient Kemp eliminase using only three mutations. The observed levels of catalytic efficiency exceed those of proteins designed using current approaches and are similar with those of natural enzymes for the reactions that they are evolved to catalyse. Given the simplicity of this experimental approach, which requires no a priori structural or bioinformatic knowledge, we expect it to be widely applicable and to enable the full potential of directed enzyme evolution.


Asunto(s)
Evolución Molecular Dirigida , Espectroscopía de Resonancia Magnética , Biocatálisis , Dominio Catalítico/genética , Evolución Molecular Dirigida/métodos , Mutación , Mioglobina/química , Mioglobina/genética , Mioglobina/metabolismo , Oxígeno/metabolismo
2.
Int J Mol Sci ; 25(3)2024 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-38339162

RESUMEN

Globally, women have been adopting oocyte cryopreservation (OC) for fertility preservation for various reasons, such as inevitable gonadotoxic treatment for specific pathologic states and social preferences. While conventional vitrification (C-VIT) has improved the success rate of OC, challenges of possible toxicities of high-concentration cryoprotective agents and osmotic stress persist. To overcome these challenges, we evaluated the ultra-fast vitrification (UF-VIT) method, which reduces the equilibration solution stage exposure time compared to C-VIT by observing mouse oocyte intracellular organelles and embryonic development. Consequently, compared to fresh mouse oocytes, UF-VIT presented significant differences only in endoplasmic reticulum (ER) intensity and mitochondrial (MT) distribution. Meanwhile, C-VIT showed substantial differences in the survival rate, key ER and MT parameters, and embryonic development rate. UF-VIT exhibited considerably fewer negative effects on key MT parameters and resulted in a notably higher blastocyst formation rate than C-VIT. Meiotic spindle (spindle and chromosomes) morphology showed no significant changes between the groups during vitrification/warming (VW), suggesting that VW did not negatively affect the meiotic spindle of the oocytes. In conclusion, UF-VIT seems more effective in OC owing to efficient cytoplasmic water molecule extraction, osmotic stress reduction, and minimization of cell contraction and expansion amplitude, thus compensating for the drawbacks of C-VIT.


Asunto(s)
Crioprotectores , Vitrificación , Femenino , Animales , Ratones , Humanos , Crioprotectores/farmacología , Presión Osmótica , Criopreservación/métodos , Oocitos
3.
Small ; 19(46): e2301673, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37452514

RESUMEN

Macrophages are specialized phagocytes that play central roles in immunity and tissue repair. Their diverse functionalities have led to an evolution of new allogenic and autologous macrophage products. However, realizing the full therapeutic potential of these cell-based therapies requires development of imaging technologies that can track immune cell migration within tissues in real-time. Such innovations will not only inform treatment regimens and empower interpretation of therapeutic outcomes but also enable prediction and early intervention during adverse events. Here, phase-changing nanoemulsion contrast agents are reported that permit real-time, continuous, and high-fidelity ultrasound imaging of macrophages in situ. Using a de novo designed peptide emulsifier, liquid perfluorocarbon nanoemulsions are prepared and show that rational control over interfacial peptide assembly affords formulations with tunable acoustic sensitivity, macrophage internalization, and in cellulo stability. Imaging experiments demonstrate that emulsion-loaded macrophages can be readily visualized using standard diagnostic B-mode and Doppler ultrasound modalities. This allows on-demand and long-term tracking of macrophages within porcine coronary arteries, as an exemplary model. The results demonstrate that this platform is poised to open new opportunities for non-invasive, contrast-enhanced imaging of cell-based immunotherapies in tissues, while leveraging the low-cost, portable, and safe nature of diagnostic ultrasound.


Asunto(s)
Macrófagos , Fagocitos , Animales , Porcinos , Ultrasonografía , Péptidos
4.
Chemistry ; 27(17): 5388-5392, 2021 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-33460473

RESUMEN

The self-assembly of short peptides gives rise to versatile nanomaterials capable of promoting efficient catalysis. We have shown that short, seven-residue peptides bind hemin to produce functional catalytic materials which display highly efficient peroxidation activity, reaching a catalytic efficiency of 3×105 m-1 s-1 . Self-assembly is essential for catalysis as non-assembling controls show no activity. We have also observed peroxidase activity even in the absence of hemin, suggesting the potential to alter redox properties of substrates upon association with the assemblies. These results demonstrate the practical utility of self-assembled peptides in various catalytic applications and further support the evolutionary link between amyloids and modern-day enzymes.


Asunto(s)
Nanoestructuras , Péptidos , Catálisis , Oxidación-Reducción , Péptidos/metabolismo , Peroxidasa , Peroxidasas
5.
Graefes Arch Clin Exp Ophthalmol ; 259(1): 61-68, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32648156

RESUMEN

PURPOSE: To investigate the topographic changes in the retinal capillary plexus and the choriocapillaris according to the severity of diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA). METHODS: Subjects were recruited and classified into one of the following four groups: normal controls (n = 52), diabetes without DR (n = 49), non-proliferative DR (n = 51) and proliferative DR (n = 38). Using OCTA, the superficial capillary plexus (SCP), deep capillary plexus (DCP) and the choriocapillaris vessel densities were measured and compared in different macular areas: the fovea (1-mm diameter circular area), parafovea (1-3-mm diameter ring) and perifovea (3-6-mm ring). RESULTS: With DR progression, vessel densities in the SCP and DCP as well as the choriocapillaris decreased, while the foveal avascular zone area increased (p < 0.001 for all). Compared with controls, the SCP and DCP vessel densities of the diabetes without DR group were decreased in all areas of the macula (p < 0.020 for all), while the choriocapillaris vessel density was decreased only in the perifoveal area (p = 0.823 for the foveal area; p = 0.631 for the parafoveal area; p = 0.039 for the perifoveal area). Multivariate linear regression analyses revealed that all retinal and choroidal microvascular indices were significantly associated with the DR severity. CONCLUSION: The morphological changes in the macular microvasculature were associated with DR severity. Also, the changes were found to be more vulnerable in the retinal capillary plexuses than the choriocapillaris.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Coroides , Retinopatía Diabética/diagnóstico , Angiografía con Fluoresceína , Humanos , Microvasos , Vasos Retinianos , Tomografía de Coherencia Óptica
6.
BMC Ophthalmol ; 21(1): 186, 2021 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-33888073

RESUMEN

BACKGROUND: Retrobulbar hemorrhage (RBH) is a rare complication after orbital surgery but associated with ocular complications including blindness. The aim of this study was to identify clinical characteristics of patients with RBH requiring emergent orbital decompression after blowout fracture repair. METHOD: A retrospective review of 426 blowout fracture patients at a tertiary oculoplastic clinic provided data regarding demographics, physical examination findings, and computed tomography (CT) images. Extraocular motility had been recorded in patient charts on a scale from 0 to - 4. Patients requiring emergent orbital decompression due to RBH after surgery (RBH group) were compared with those who did not (Control group), using the Mann-Whitney U-test. Incidences of RBH according to primary or secondary surgery were also investigated, using Fisher's exact test. RESULT: Five (1.2%) of the 426 patients who underwent blowout fracture repair developed RBH requiring emergent intervention. All RBH patients fully recovered after the decompression procedure or conservative treatment. Number of days to surgery was significantly longer in the RBH group (97.0 ± 80.1) than in the Control group (29.0 ± 253.0) (p = 0.05). Preoperative enophthalmos was also significantly greater in the RBH group (RBH vs. Control group, 3.6 ± 1.7 mm versus 1.2 ± 1.3 mm (p = 0.003)). The incidence of RBH was significantly higher in patients that underwent secondary surgery (odds ratio = 92.9 [95% confidence interval, 11.16-773.23], p = 0.001). CONCLUSIONS: Surgeons should pay more attention to hemostasis and postoperative care in patients with a large preoperative enophthalmic eye, when time from injury to surgery is long and in revision cases. When RBH occurs, time to intervention and surgical decompression is critical for visual recovery and preventing blindness. TRIAL REGISTRATION: The institutional review board of the Yeungnam University Medical Center approved this study ( YUMC 2018-11-010 ), which was conducted in accord with the Declaration of Helsinki.


Asunto(s)
Enoftalmia , Fracturas Orbitales , Hemorragia Retrobulbar , Humanos , Incidencia , Fracturas Orbitales/complicaciones , Fracturas Orbitales/cirugía , Hemorragia Retrobulbar/epidemiología , Hemorragia Retrobulbar/etiología , Estudios Retrospectivos
7.
Medicina (Kaunas) ; 57(6)2021 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-34201120

RESUMEN

Background and Objectives: Early intensive exercise after total knee replacement arthroplasty (TKRA) has become increasingly popular due to its ability to enhance knee physical function and reduce pain. When implemented exclusively, aquatic exercise (AE) appears to be more advantageous than land exercise (LE), particularly in the early phase after TKRA. Our study aimed to compare the clinical efficacy of AE and LE with respect to their effects on pain and physical function after TKRA. Materials and Methods: Between February 2008 and January 2020, 100 female patients who underwent TKRA were enrolled in this retrospective study. We measured the range of motion (ROM) of the knee, the isokinetic strength of the knee joint (function), and pain both initially and one month after TKRA. Two weeks after TKRA, the participants were enrolled in either the AE or the LE program for a total of two weeks. Two 30 min sessions of intensive ROM and knee strengthening exercises and balance training were provided to the AE and LE groups for 10 days. The home exercise group (HE) only received information on ROM and strengthening exercises. There were 33, 21, and 46 patients allocated to the AE, LE, and HE groups, respectively. Results: The ROM of the side on which surgery was performed improved significantly in all groups, as did the pain scores. In the AE group, the knee flexor strength showed a tendency toward improvement. Contrastingly, there was no significant improvement in the knee extensor strength in the AE group. Conclusions: Overall, the AE and LE groups showed superior outcomes compared with HE. In addition, the AE group demonstrated some improvement in knee muscle strength even with a short hospital stay. Further study with long-term follow-up should be performed to better define the outcomes.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Osteoartritis de la Rodilla , Anciano , Terapia por Ejercicio , Femenino , Humanos , Articulación de la Rodilla/cirugía , Fuerza Muscular , Osteoartritis de la Rodilla/cirugía , Rango del Movimiento Articular , Estudios Retrospectivos
8.
Emerg Infect Dis ; 26(8): 1666-1670, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32324530

RESUMEN

We describe the epidemiology of a coronavirus disease (COVID-19) outbreak in a call center in South Korea. We obtained information on demographic characteristics by using standardized epidemiologic investigation forms. We performed descriptive analyses and reported the results as frequencies and proportions for categoric variables. Of 1,143 persons who were tested for COVID-19, a total of 97 (8.5%, 95% CI 7.0%-10.3%) had confirmed cases. Of these, 94 were working in an 11th-floor call center with 216 employees, translating to an attack rate of 43.5% (95% CI 36.9%-50.4%). The household secondary attack rate among symptomatic case-patients was 16.2% (95% CI 11.6%- 22.0%). Of the 97 persons with confirmed COVID-19, only 4 (1.9%) remained asymptomatic within 14 days of quarantine, and none of their household contacts acquired secondary infections. Extensive contact tracing, testing all contacts, and early quarantine blocked further transmission and might be effective for containing rapid outbreaks in crowded work settings.


Asunto(s)
Betacoronavirus/patogenicidad , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Brotes de Enfermedades , Neumonía Viral/epidemiología , Neumonía Viral/transmisión , Betacoronavirus/genética , COVID-19 , Prueba de COVID-19 , Centrales de Llamados , Técnicas de Laboratorio Clínico/métodos , Trazado de Contacto/estadística & datos numéricos , Infecciones por Coronavirus/diagnóstico , Composición Familiar , Femenino , Humanos , Incidencia , Masculino , Pandemias , Neumonía Viral/diagnóstico , Cuarentena/métodos , República de Corea/epidemiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , SARS-CoV-2 , Índice de Severidad de la Enfermedad
9.
J Sci Food Agric ; 99(9): 4200-4210, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30767231

RESUMEN

BACKGROUND: Equol is a major isoflavone metabolite, and equol-producing bacteria have been isolated and characterized; however, fermentation has been performed with soybean-based products as substrates. Pueraria lobata has been reported as a plant with higher content of isoflavones. RESULTS: The genome of new equol-producing bacteria, Lactobacillus paracasei JS1, was analyzed. Also, the effect of P. lobata extract fermented with L. paracasei JS1 (FPE) on the skin and intestinal immune response was examined. With gene expression analysis, it was proven that seven skin-related proteins, hyaluronan synthase-1, -2, -3, collagen, elastin, epidermal growth factor, and epidermal growth factor receptor were differentially expressed upon FPE treatment. The messenger RNA expression increased with treatment with the FPE, and a skin moisturizing effect was confirmed by a hematoxylin-eosin staining experiment. In addition, such an experiment showed that proinflammatory cytokines, tumor necrosis factor-α, cyclooxygenase-2, inducible nitric oxide synthase, interleukin-1ß, -4, and -6, were reduced in large intestine when treated with FPE. CONCLUSION: L. paracasei JS1 has the ability to produce equol having beneficial effects on the skin. Moreover, FPE also has an inhibitory effect on inflammation cytokines in the large intestine. Thus, the novel and edible equol-producing L. paracasei JS1 and FPE have thepotential to be developed as nutricosmetic resources. © 2019 Society of Chemical Industry.


Asunto(s)
Equol/metabolismo , Enfermedades Intestinales/prevención & control , Lacticaseibacillus paracasei/metabolismo , Probióticos/administración & dosificación , Enfermedades de la Piel/prevención & control , Animales , Colágeno/genética , Colágeno/metabolismo , Elastina/genética , Elastina/metabolismo , Fermentación , Humanos , Hialuronano Sintasas/genética , Hialuronano Sintasas/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Enfermedades Intestinales/genética , Enfermedades Intestinales/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Enfermedades de la Piel/genética , Enfermedades de la Piel/metabolismo
10.
Biomacromolecules ; 18(11): 3600-3610, 2017 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-28836431

RESUMEN

Gadolinium (Gd[III])-based nanoaggregates are potential noninvasive magnetic resonance imaging (MRI) probes with excellent spatial and temporal resolution for cancer diagnosis. Peptides conjugated with Gd3+ can aid in supramolecular scaffolding for MRI nanoagents because of their inherent biocompatibility and degradability. We report here a strategy to tune the MR relaxivity of tumor cell-targeted nanoagents and enhance the antimicrobial and anticancer activities of nanoagents based on rationally designed antimicrobial peptide (AMP) assembly. A tripeptide with glycyl-l-histidyl-l-lysine (GHK) capable of Gd3+ chelation was attached to short AMPs containing pyrazole amino acids that spontaneously assembled as a function of the number of hydrophobic amino acid residues and the peptide length of AMPs. Aqueous coassembly of GHK with tumor-targeting, cyclic arginine-glycine-aspartic acid (cRGD)-tagged AMPs resulted in the formation of micelles, fibrils, vesicles, sheets, and planar networks. Interestingly, the two-dimensional planar network nanostructure showed less antibacterial activity and tumor cell cytotoxicity but greater drug loading/delivery and magnetic resonance signaling than micelles because of its intrinsic structural characteristics. This study can provide a rational approach for the design and fabrication of clinically useful nanoagents.


Asunto(s)
Gadolinio/química , Neoplasias/tratamiento farmacológico , Péptidos/química , Nanomedicina Teranóstica , Antiinfecciosos/química , Medios de Contraste/química , Medios de Contraste/uso terapéutico , Sistemas de Liberación de Medicamentos , Gadolinio/uso terapéutico , Humanos , Imagen por Resonancia Magnética , Micelas , Neoplasias/patología , Péptidos/uso terapéutico
11.
J Cell Sci ; 127(Pt 22): 4954-63, 2014 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25271058

RESUMEN

Fasting and glucose shortage activate a metabolic switch that shifts more energy production to mitochondria. This metabolic adaptation ensures energy supply, but also elevates the risk of mitochondrial oxidative damage. Here, we present evidence that metabolically challenged mitochondria undergo active fusion to suppress oxidative stress. In response to glucose starvation, mitofusin 1 (MFN1) becomes associated with the protein deacetylase HDAC6. This interaction leads to MFN1 deacetylation and activation, promoting mitochondrial fusion. Deficiency in HDAC6 or MFN1 prevents mitochondrial fusion induced by glucose deprivation. Unexpectedly, failure to undergo fusion does not acutely affect mitochondrial adaptive energy production; instead, it causes excessive production of mitochondrial reactive oxygen species and oxidative damage, a defect suppressed by an acetylation-resistant MFN1 mutant. In mice subjected to fasting, skeletal muscle mitochondria undergo dramatic fusion. Remarkably, fasting-induced mitochondrial fusion is abrogated in HDAC6-knockout mice, resulting in extensive mitochondrial degeneration. These findings show that adaptive mitochondrial fusion protects metabolically challenged mitochondria.


Asunto(s)
GTP Fosfohidrolasas/metabolismo , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Acetilación , Animales , GTP Fosfohidrolasas/genética , Histona Desacetilasa 6 , Histona Desacetilasas/deficiencia , Histona Desacetilasas/metabolismo , Ratones , Dinámicas Mitocondriales , Estrés Oxidativo
12.
Chemistry ; 22(45): 16157-16164, 2016 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-27689935

RESUMEN

Three new cobalt-ruthenium heterometallic molecular rectangles, 1-3, were synthesized through the coordination-driven self-assembly of a new cobalt sandwich donor, (η5 -Cp)Co[C4 -trans-Ph2 (4-Py)2 ] (L; Cp: cyclopentyl; Py: pyridine), and one of three dinuclear precursors, [(p-cymene)2 Ru2 (OO∩OO)2 Cl2 ] [OO∩OO: oxalato (A1 ), 5,8-dioxido-1,4-naphthoquinone (A2 ), or 6,11-dioxido-5,12-naphthacenedione (A3 )]. All of the self-assembled architectures were isolated in very good yield (92-94 %) and were fully characterized by spectroscopic analysis; the molecular structures of 2 and 3 were determined by single-crystal X-ray diffraction analysis. The anticancer activities of bimetallic rectangles 1-3 were evaluated with a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay, an autophagy assay, and Western blotting. Rectangles 1-3 showed higher cytotoxicity than doxorubicin in AGS human gastric carcinoma cells. In addition, the autophagic activities and apoptotic cell death ratios were increased in AGS cells by treatment with 1-3; the rectangles induced autophagosome formation by promoting LC3-I to LC3-II conversion and apoptotic cell death by increasing caspase-3/7 activity. Our results suggest that rectangles 1-3 induce gastric cancer cell death by modulating autophagy and apoptosis and that they have potential use as agents for the treatment of human gastric cancer.

13.
Biomacromolecules ; 17(10): 3234-3243, 2016 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-27589588

RESUMEN

We report a simple and facile strategy for the preparation of multifunctional nanoparticles with programmable properties using self-assembly of precisely designed block amphiphiles in an aqueous solution-state. Versatile, supramolecular nanoplatform for personalized needs, particularly-theranostics, was fabricated by coassembly of peptide amphiphiles (PAs) in aqueous solution, replacing time-consuming and inaccessible chemical synthesis. Fibrils, driven by the assembly of hydrophobic ß-sheet-forming peptide block, were utilized as a nanotemplate for drug loading within their robust core. PAs were tagged with octreotide [somatostatin (SST) analogue] for tumor-targeting or were conjugated with paramagnetic metal ion (Gd3+)-chelating 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) for magnetic resonance (MR) imaging. The two PA types were coassembled to integrate each PA function into original fibrillar nanotemplates. The adoption of a bulky target-specific cyclic octreotide and ß-sheet-forming peptide with enhanced hydrophobicity led to a morphological transition from conventional fibrils to helical fibrils. The resulting one-dimensional nanoaggregates allowed the successful intracellular delivery of doxorubicin (DOX) to MCF-7 cancer cells overexpressing SST receptor (SSTR) and MR imaging by enabling high longitudinal (T1) relaxivity of water protons. Correlation between the structural nature of fibrils formed by PA coassembly and contrast efficacy was elucidated. The coassembly of PAs with desirable functions may thus be a useful strategy for the generation of tailor-made biocompatible nanomaterials.


Asunto(s)
Técnicas de Transferencia de Gen , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Péptidos/química , Doxorrubicina/administración & dosificación , Doxorrubicina/química , Compuestos Heterocíclicos con 1 Anillo/administración & dosificación , Compuestos Heterocíclicos con 1 Anillo/química , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Células MCF-7 , Imagen por Resonancia Magnética , Nanopartículas/administración & dosificación , Péptidos/administración & dosificación , Soluciones/química , Tensoactivos/administración & dosificación , Tensoactivos/química , Nanomedicina Teranóstica , Agua/química
14.
J Geriatr Psychiatry Neurol ; 29(3): 160-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26956224

RESUMEN

The primary goals of the present study were to develop and validate the Rappel Indicé 24 (RI-24), a shorter version of the original Rappel Indicé, which includes 48 items (RI-48), and to identify the specific brain regions that were correlated with scores on the RI-24. Using these clinical scales, the present study evaluated 91 elderly Korean participants who were classified into 3 groups: normal control (NC; n = 34), patients with mild cognitive impairment (MCI; n = 29), and patients with Alzheimer disease (AD; n = 28). Of the 91 participants, 77 also underwent magnetic resonance imaging scans. The RI-24 delayed cued recall (DCR) scores significantly differed among the NC, MCI, and AD groups. A receiver-operating characteristic curve analysis revealed that the RI-24 was very sensitive (89%) and specific (91%) for the detection of AD. Furthermore, although the time needed to administer the RI-24 was half that needed for the RI-48, the 24-item version showed a high correlation (r= .85 for the DCR score) with the 48-item version. In terms of brain morphological characteristics, voxel-based morphometry analyses revealed a significant positive correlation between DCR score and gray matter volume in the parahippocampal gyrus (r= .468), which plays a role in cued recall. Taken together, the present findings indicate that the RI-24 is a sensitive and reliable test for the detection of memory impairments in patients with MCI and AD despite its brief administration time.


Asunto(s)
Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/psicología , Encéfalo/patología , Disfunción Cognitiva/patología , Disfunción Cognitiva/psicología , Trastornos de la Memoria/complicaciones , Trastornos de la Memoria/diagnóstico , Anciano , Enfermedad de Alzheimer/complicaciones , Pueblo Asiatico , Encéfalo/fisiopatología , Disfunción Cognitiva/complicaciones , Señales (Psicología) , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Trastornos de la Memoria/patología , Trastornos de la Memoria/psicología , Recuerdo Mental , Pruebas Neuropsicológicas , Curva ROC , República de Corea
15.
Pharm Biol ; 54(10): 2135-40, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26911402

RESUMEN

Context Diabetes is a common metabolic disease with long-term complications. Prunus mume Sieb. et Zucc. (Rosaceae) fruits have shown to ameliorate glucose intolerance. However, the antidiabetic effects of P. mume leaves have not been investigated. Objective This study evaluated the effects of P. mume leaf 70% ethanol extract (PMLE) on alleviating diabetes in vivo and in vitro. Materials and methods PMLE was fractionated into n-hexane, dichloromethane (CH2Cl2), ethyl acetate (EtOAc), n-butanol (BuOH) and water. Polyphenol and flavonoid contents in PMLE fractions were determined using Folin-Ciocalteu reagent and the aluminium chloride colorimetric method, respectively. We evaluated α-glucosidase inhibition using a microplate reader at 400 nm. Adipocyte differentiation by lipid accumulation was measured using Nile Red staining. Male imprinting control region (ICR) mice were injected with streptozotocin (STZ, 100 mg/kg, i.p.). High-fat diets were provided for three weeks prior to PMLE treatments to induce type 2 diabetes. PMLE (0, 5, 25 or 50 mg/kg) was administrated for four weeks with high-fat diets. Results The EtOAc fraction of PMLE inhibited α-glucosidase activity (IC50 = 68.2 µg/mL) and contained 883.5 ± 14.9 mg/g of polyphenols and 820.1 ± 7.7 mg/g of flavonoids. The 50 mg/kg PMLE supplement reduced 40% of blood glucose level compared to obese/diabetes mice. Obese/diabetic mice treated with 50 mg/kg PMLE showed a lower level of triacylglycerol (320.7 ± 20.73 mg/dL) compared to obese/diabetes mice (494.9 ± 14.80 mg/dL). Conclusion The data demonstrate that P. mume leaves exert antidiabetic effects that may be attributable to high concentrations of polyphenols and flavonoids.


Asunto(s)
Glucemia/efectos de los fármacos , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores de Glicósido Hidrolasas/farmacología , Hipolipemiantes/farmacología , Extractos Vegetales/farmacología , Animales , Biomarcadores/sangre , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Colesterol/sangre , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/etiología , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/etiología , Dieta Alta en Grasa , Dislipidemias/sangre , Dislipidemias/tratamiento farmacológico , Dislipidemias/etiología , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Hipolipemiantes/aislamiento & purificación , Masculino , Ratones Endogámicos ICR , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta , Plantas Medicinales , Prunus/química , Triglicéridos/sangre
16.
J Am Chem Soc ; 137(38): 12394-9, 2015 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-26349620

RESUMEN

We report the formation of supramolecular coordination polymers formed from multiporphyrin dendrimers (PZnPM; M = FB or Cu), composed of the focal freebase porphyrin (PFB) or cupper porphyrin (PCu) with eight zinc porphyrin (PZn) wings, and multipyridyl porphyrins (PyPM; M = FB or Cu), PFB or PCu with eight pyridyl groups, through multiple axial coordination interactions of pyridyl groups to PZns. UV-vis absorption spectra were recorded upon titration of PyPFB to PZnPFB. Differential spectra, obtained by subtracting the absorption of PZnPFB without guest addition as well as the absorption of PyPFB, exhibited clear isosbestic points with saturation binding at 1 equiv addition of PyPFB to PZnPFB. Job's plot analysis also indicated 1:1 stoichiometry for the saturation binding. The apparent association constant between PZnPFB and PyPFB (2.91 × 10(6) M(-1)), estimated by isothermal titration calorimetry, was high enough for fibrous assemblies to form at micromolar concentrations. The formation of a fibrous assembly from PZnPFB and PyPFB was visualized by atomic force microscopy and transmission electron microscopy (TEM). When a 1:1 mixture solution of PZnPFB and PyPFB (20 µM) in toluene was cast onto mica, fibrous assemblies with regular height (ca. 2 nm) were observed. TEM images obtained from 1:1 mixture solution of PZnPFB and PyPFB (0.1 wt %) in toluene clearly showed the formation of nanofibers with a regular diameter of ca. 6 nm. Fluorescence emission measurement of PZnPM indicated efficient intramolecular energy transfer from PZn to the focal PFB or PCu. By the formation of supramolecular coordination polymers, the intramolecular energy transfer changed to intermolecular energy transfer from PZnPM to PyPM. When the nonfluorescent PyPCu was titrated to fluorescent PZnPFB, fluorescence emission from the focal PFB was gradually decreased. By the titration of fluorescent PyPFB to nonfluorescent PZnPCu, fluorescence emission from PFB in PyPFB was gradually increased due to the efficient energy transfer from PZn wings in PZnPCu to PyPFB.


Asunto(s)
Dendrímeros/química , Luz , Polímeros/síntesis química , Porfirinas/química , Modelos Moleculares , Polímeros/química
17.
Macromol Rapid Commun ; 36(11): 1069-74, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25639812

RESUMEN

Zero-dimensional (0D) nanospheres, 1D nanocaterpillars, and 3D aggregates are produced from simple diblock copolymers containing polyacetylene (PA) via in situ nanoparticlization of conjugated polymers. The diblock copolymers are prepared by ring-opening metathesis polymerization via one-pot sequential addition of an endo-tricyclo[4.2.2.0]deca-3,9-diene (TD) and cyclooctatetraene. Initially, they spontaneously form nanospheres consisting of a PA core and PTD shell, and increasing the length of the PA block leads to the direct nanoparticlization of the higher-dimensional structures such as 1D and 3D aggregates because of the decreased effective volume ratio of the rigid PTD shell to the solvophobic PA core.


Asunto(s)
Nanopartículas/química , Polímeros/síntesis química , Microscopía de Fuerza Atómica , Nanopartículas/ultraestructura , Polimerizacion , Polímeros/química , Poliinos/química
18.
J Nanosci Nanotechnol ; 15(1): 134-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26328317

RESUMEN

Plasma treatments are becoming a popular method for modifying the characteristics of a range of substrate surfaces. Atmospheric pressure plasma is cost-efficient, safe and simple compared to high-pressure plasma. This study examined the effects of atmospheric pressure plasma to a titanium (Ti) surface on osteoblast-like cell (osteoblast) spreading and cellular networks. The characteristics of the Ti surface before and after the atmospheric plasma treatment were analyzed by X-ray photoemission spectroscopy (XPS), scanning electron microscopy (SEM), contact angle measurements, and an optical 3D profiling system. The morphology of osteoblasts attached to the Ti surfaces was observed by SEM and confocal laser scanning microscopy. The atmospheric pressure plasma made the Ti surfaces more hydrophilic. The osteoblasts that adhered to the untreated surface were round and spherical, whereas the cells covered a larger surface area on the plasma-treated surface. The plasma-treated Ti surface showed enhanced cell spreading and migration with more developed cellular networks. In conclusion, an atmospheric plasma treatment is a potential surface modifying method that can enhance the initial the cell affinity at the early stages in vitro.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Osteoblastos/efectos de los fármacos , Gases em Plasma/farmacología , Titanio/química , Animales , Presión Atmosférica , Línea Celular , Ratones , Gases em Plasma/química , Propiedades de Superficie
19.
Epidemiol Health ; 46: e2024013, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38228090

RESUMEN

OBJECTIVES: This study examined the effectiveness of community-based interventions designed for older adults living alone through a systematic review and meta-analysis. METHODS: The study incorporated 4 randomized controlled trials (RCTs) and 5 non-RCTs to evaluate various interventions. The methodological quality of these studies was assessed using the Downs and Black checklist, while Q-statistic and I-square tests were performed to examine statistical heterogeneity. Additionally, visual inspection of funnel plots and the trim-and-fill method were employed to investigate potential publication bias. Of the 2,729 identified studies, 9 met the criteria for inclusion in this review. Independent variables were categorized into 5 groups (physical activity, nutrition, social relationships, social participation, and combined intervention) to examine their effects. Dependent variables were similarly classified into 5 subgroups to identify the specific effects of the interventions. RESULTS: Interventions focusing on nutrition and combined approaches were the most effective, yielding effect sizes of 0.96 (95% confidence interval [CI], 0.66 to 1.25) and 0.43 (95% CI, 0.26 to 0.60), respectively. The interventions had the greatest impacts on the health behavior and mental health of the participants, with effect sizes of 0.98 (95% CI, 0.73 to 1.22) for health behavior and 0.67 (95% CI, 0.19 to 1.16) for mental health. CONCLUSIONS: This study suggests a direction for the development of community-based interventions tailored to the needs of older adults living alone. Additionally, it provides evidence to inform policy decisions concerning this demographic.

20.
ACS Omega ; 9(23): 25094-25105, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38882105

RESUMEN

Nonalcoholic fatty liver disease (NAFLD), which is a major cause of chronic liver disease, is characterized by fat accumulation in the liver. Existing models struggle to assess medication effects on liver function in the context of NAFLD's unique inflammatory environment. We address this by developing a 3D in vitro NAFLD model using HepG2 and THP-1 cells (mimicking liver and Kupffer cells) cocultured using transwell and hydrogel system. This mimics liver architecture and allows for manipulation of the immune environment. We demonstrate that the model recapitulates key NAFLD features: steatosis (induced by fatty acids), oxidative stress, inflammation, and impaired liver function embodying the interrelationship between NAFLD and the surrounding immune environment. This versatile model offers a valuable tool for preclinical NAFLD research by incorporating a disease-relevant immune environment.

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