Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Circulation ; 149(15): 1183-1201, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38099436

RESUMO

BACKGROUND: Atherosclerosis preferentially occurs in arterial regions of disturbed blood flow, and stable flow (s-flow) protects against atherosclerosis by incompletely understood mechanisms. METHODS: Our single-cell RNA-sequencing data using the mouse partial carotid ligation model was reanalyzed, which identified Heart-of-glass 1 (HEG1) as an s-flow-induced gene. HEG1 expression was studied by immunostaining, quantitive polymerase chain reaction, hybridization chain reaction, and Western blot in mouse arteries, human aortic endothelial cells (HAECs), and human coronary arteries. A small interfering RNA-mediated knockdown of HEG1 was used to study its function and signaling mechanisms in HAECs under various flow conditions using a cone-and-plate shear device. We generated endothelial-targeted, tamoxifen-inducible HEG1 knockout (HEG1iECKO) mice. To determine the role of HEG1 in atherosclerosis, HEG1iECKO and littermate-control mice were injected with an adeno-associated virus-PCSK9 [proprotein convertase subtilisin/kexin type 9] and fed a Western diet to induce hypercholesterolemia either for 2 weeks with partial carotid ligation or 2 months without the surgery. RESULTS: S-flow induced HEG1 expression at the mRNA and protein levels in vivo and in vitro. S-flow stimulated HEG1 protein translocation to the downstream side of HAECs and release into the media, followed by increased messenger RNA and protein expression. HEG1 knockdown prevented s-flow-induced endothelial responses, including monocyte adhesion, permeability, and migration. Mechanistically, HEG1 knockdown prevented s-flow-induced KLF2/4 (Kruppel-like factor 2/4) expression by regulating its intracellular binding partner KRIT1 (Krev interaction trapped protein 1) and the MEKK3-MEK5-ERK5-MEF2 pathway in HAECs. Compared with littermate controls, HEG1iECKO mice exposed to hypercholesterolemia for 2 weeks and partial carotid ligation developed advanced atherosclerotic plaques, featuring increased necrotic core area, thin-capped fibroatheroma, inflammation, and intraplaque hemorrhage. In a conventional Western diet model for 2 months, HEG1iECKO mice also showed an exacerbated atherosclerosis development in the arterial tree in both sexes and the aortic sinus in males but not in females. Moreover, endothelial HEG1 expression was reduced in human coronary arteries with advanced atherosclerotic plaques. CONCLUSIONS: Our findings indicate that HEG1 is a novel mediator of atheroprotective endothelial responses to flow and a potential therapeutic target.


Assuntos
Aterosclerose , Hipercolesterolemia , Placa Aterosclerótica , Masculino , Feminino , Humanos , Camundongos , Animais , Placa Aterosclerótica/metabolismo , Pró-Proteína Convertase 9/metabolismo , Células Endoteliais/metabolismo , Hipercolesterolemia/genética , Aterosclerose/genética , Aterosclerose/prevenção & controle , Aterosclerose/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Proteínas de Membrana/metabolismo
2.
Angew Chem Int Ed Engl ; 61(11): e202115695, 2022 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-35043545

RESUMO

The emergence of SARS-CoV-2 variants is a significant concern in developing effective therapeutics and vaccines in the middle of the ongoing COVID-19 pandemic. Here, we have identified a novel small molecule that inhibited the interactions between SARS-CoV-2 spike RBDs and ACE2 by modulating ACE2 without impairing its enzymatic activity necessary for normal physiological functions. Furthermore, the identified compounds suppressed viral infection in cultured cells by inhibiting the entry of ancestral and variant SARS-CoV-2. Our study suggests that targeting ACE2 could be a novel therapeutic strategy to inhibit SARS-CoV-2 entry into host cells and prevent the development of COVID-19.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , SARS-CoV-2/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus/efeitos dos fármacos , Animais , Antivirais/química , COVID-19/metabolismo , Chlorocebus aethiops , Descoberta de Drogas , Humanos , Mapas de Interação de Proteínas/efeitos dos fármacos , SARS-CoV-2/fisiologia , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Células Vero
3.
Korean J Food Sci Anim Resour ; 38(3): 506-514, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30018495

RESUMO

The aim of this study was to evaluate the effects of marinade under different conditions (temperature and vacuum) on pork ham cooked by the sous-vide method (61°C and 98.81% vacuum for 45 min). Control group was non-marinade pork ham. The samples were marinated under 1 of 4 conditions: 4°C, 98.81% vacuum (treatment group T1); 4°C, atmospheric pressure (T2); 20°C, 98.81% vacuum (T3); and 20°C, atmospheric pressure (T4). The pH value was higher in the control (6.02) than in the treatment groups (4.30-4.42, p<0.001). Shear force was the lowest in the control: 18.14 N. Lightness and redness values were higher in the control (p<0.001). The chroma value significantly decreased from 12.74 to 7.55 with marinade (p<0.001). Total viable and coliform counts of raw meat were 84.6 and 3.67 Log CFU/g, respectively. After the marinade, the total viable count decreased to 3.00-14.67 Log CFU/g (p<0.001). Coliforms were not detected. After sous-vide cooking, no viable microorganisms were detected in any group. Treatment groups generally showed high scores on consumer preference. The marinade and sous-vide cooking had a positive effect on sensory characteristics. They provided safe conditions for sanitary evaluation. As a result, it appears that marinade at refrigeration temperature is better than that at room temperature.

4.
Meat Sci ; 143: 1-7, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29684839

RESUMO

This study evaluated the influence of different factors on pork hams cooked by sous-vide method. The quality and structural and microbiological properties of the treated samples were compared with those of controls. Samples were subjected to treatment at different combinations of temperature (61 °C or 71 °C), time (45 or 90 min), and vacuum degree (98.81% or 96.58%). The control sample was air packaged and boiled for 45 min in boiling water. Temperature and vacuum degree affected quality properties, while the effect of time was limited. Samples cooked at 61 °C showed higher moisture content, redness, and pink color of the meat juice, whereas samples cooked at 71 °C showed higher cooking loss rate, lightness, and volatile basic nitrogen values. Texture analysis indicated tenderer meat for the treatment group than the control. No microbial growth was detected in any treatment groups. Meat cooked at 61 °C and 98.81% vacuum showed more spacious arrangement of meat fiber.


Assuntos
Culinária , Embalagem de Alimentos , Qualidade dos Alimentos , Alimentos Congelados/análise , Carne/análise , Algoritmos , Animais , Alimentos Congelados/microbiologia , Temperatura Alta , Carne/microbiologia , Viabilidade Microbiana , Microscopia Eletrônica de Varredura , Fibras Musculares Esqueléticas/química , Fibras Musculares Esqueléticas/ultraestrutura , Pigmentos Biológicos/análise , Pigmentos Biológicos/química , República da Coreia , Resistência ao Cisalhamento , Propriedades de Superfície , Sus scrofa , Fatores de Tempo , Vácuo , Água/análise
5.
J Control Release ; 270: 237-245, 2018 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-29247665

RESUMO

This paper describes the fabrication and evaluation of phase-change material (PCM) nanoparticles containing chlorin e6 (Ce6) and nanodiamonds (NDs) for photodynamic and photothermal approaches for tumor therapy, respectively. The temperature of the PCM nanoparticles containing NDs (ND/PCM, 0.5mg/mL in water) is increased to 45°C during laser exposure for 5min. The singlet oxygen generation intensity of PCM nanoparticles containing Ce6 and NDs (Ce6/ND/PCM) is gradually increased with respect to the laser exposure time. Also, the release of Ce6 from Ce6/ND/PCM can be controlled in an on-and-off manner using laser. Cell ablation tests reveal that Ce6/ND/PCM greatly ablates KB cells upon laser exposure, which is attributed to both the temperature increase in the media and singlet oxygen generation by the released Ce6. In an animal model, tumor volume is notably reduced over time after the intratumoral injection of Ce6/ND/PCM and subsequent laser exposure with a higher efficiency compared to ND/PCM. The Ce6/ND/PCM can be a promising nanomedicine for tumor therapy.


Assuntos
Lasers , Nanopartículas/administração & dosagem , Neoplasias/terapia , Fototerapia , Porfirinas/administração & dosagem , Radiossensibilizantes/administração & dosagem , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Clorofilídeos , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Neoplasias/patologia , Porfirinas/química , Radiossensibilizantes/química , Oxigênio Singlete/química
6.
J Control Release ; 232: 152-60, 2016 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-27094604

RESUMO

This paper describes the design of alendronate-conjugated nanodiamonds (Alen-NDs) and evaluation of their feasibility for bone-targeted delivery. Alen-NDs exhibited a high affinity to hydroxyapatite (HAp, the mineral component of bone) due to the presence of Alen. Unlike NDs (without Alen), Alen-NDs were preferentially taken up by MC3T3-E1 osteoblast-like cells, compared to NIH3T3 and HepG2 cells, suggesting their cellular specificity. In addition, NDs itself increased ALP activity of MC3T3-E1 cells, compared to control group (osteogenic medium) and Alen-NDs exhibited more enhanced ALP activity. In addition, an in vivo study revealed that Alen-NDs effectively accumulated in bone tissues after intravenous tail vein injection. These results confirm the superior properties of Alen-NDs with advantages of high HAp affinity, specific uptake for MC3T3-E1 cells, positive synergistic effect for ALP activity, and in vivo bone targeting ability. The Alen-NDs can potentially be employed for osteoporosis treatment by delivering both NDs and Alen to bone tissue.


Assuntos
Alendronato/administração & dosagem , Conservadores da Densidade Óssea/administração & dosagem , Portadores de Fármacos/administração & dosagem , Nanodiamantes/administração & dosagem , Alendronato/química , Alendronato/farmacocinética , Fosfatase Alcalina/metabolismo , Animais , Conservadores da Densidade Óssea/química , Conservadores da Densidade Óssea/farmacocinética , Osso e Ossos/metabolismo , Linhagem Celular , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Durapatita/química , Feminino , Células Hep G2 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanodiamantes/química , Osteoporose/tratamento farmacológico
7.
Biomed Opt Express ; 5(8): 2837-42, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25136506

RESUMO

We demonstrated that tumors in freshly excised whole brain tissue could be differentiated clearly from normal brain tissue using a reflection-type terahertz (THz) imaging system. THz binary images of brain tissues with tumors indicated that the tumor boundaries in the THz images corresponded well to those in visible images. Grey and white-matter regions were distinguishable owing to the different distribution of myelin in the brain tissue. THz images corresponded closely with magnetic resonance imaging (MRI) results. The MRI and hematoxylin and eosin-stained microscopic images were investigated to account for the intensity differences in the THz images for fresh and paraffin-embedded brain tissue. Our results indicated that the THz signals corresponded to the cell density when water was removed. Thus, THz imaging could be used as a tool for label-free and real-time imaging of brain tumors, which would be helpful for physicians to determine tumor margins during brain surgery.

8.
Biomed Opt Express ; 5(12): 4162-70, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25574429

RESUMO

We have investigated basic properties of normal gastrointestinal (GI) tract tissues, including glandular stomach (GS), fore stomach (FS), large intestine (LI), small intestine (SI), and esophagus (ESO), from a rat model using terahertz (THz) reflection imaging and spectroscopy. The THz images collected from stratified squamous epithelia (SSE) of FS and ESO show a lower peak-to-peak value compared to those from columnar epithelia (CE) of GS, LI, or SI because the SSE contains less water than CE. The refractive index and absorption coefficient of FS were less than those of GS or LI, both having values similar to those of water. Additionally, we report internal reflection THz signals from ESO, although we were unable to determine the exact interface for this internal reflection.

9.
Opt Express ; 21(18): 21299-305, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-24104004

RESUMO

We demonstrate the use of a THz penetration-enhancing agent (THz-PEA) to enhance the terahertz (THz) wave penetration depth in tissues. The THz-PEA is a biocompatible material having absorption lower than that of water, and it is easily absorbed into tissues. When using glycerol as a THz-PEA, the peak value of the THz signal which was transmitted through the fresh tissue and reflected by a metal target, was almost doubled compared to that of tissue without glycerol. THz time-of-flight imaging (B-scan) was used to display the sequential glycerol delivery images. Enhancement of the penetration depth was confirmed after an artificial tumor was located below fresh skin. We thus concluded that the THz-PEA technique can potentially be employed to enhance the image contrast of the abnormal lesions below the skin.


Assuntos
Aumento da Imagem , Imagem Terahertz/métodos , Animais , Etanol/química , Glicerol/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/diagnóstico , Vaselina/química , Fatores de Tempo , Água/química
10.
J Biomed Opt ; 18(10): 107008, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24165743

RESUMO

We show that terahertz (THz) time-domain spectroscopy (TDS) can be used to characterize the blood. The complex optical constants of blood and its constituents, such as water, plasma, and red blood cells (RBCs), were obtained in the THz frequency region. The volume percentage of RBCs in blood was extracted and compared with the conventional RBC counter results. The THz absorption constants are shown to vary linearly with the RBC concentration in both normal saline and whole blood. The excellent linearity between the THz signal and the RBC concentration was also confirmed in a polyurethane resin tube using a THz imaging method. These results demonstrate that THz-TDS imaging can facilitate the quantitative analysis of blood.


Assuntos
Eritrócitos/química , Testes Hematológicos/métodos , Plasma/química , Espectroscopia Terahertz/métodos , Absorção , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Refratometria
11.
J Clin Neurol ; 3(3): 139-46, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19513281

RESUMO

BACKGROUND AND PURPOSE: Congenital nystagmus (CN) is an ocular oscillation that usually manifests during early infancy. Typical features of CN include bilateral, conjugate, uniplanar, and usually horizontal eye movements, a null position, increased oscillation during fixation, and decreased amplitude during convergence. Our purposes were description and analysis of clinical and oculomotor findings of patients with X-linked familial CN. METHODS: We describe the clinical and oculographic features of five patients from three families with X-linked CN. Three-dimensional video-oculography disclosed various patterns of CN and variable degrees of gaze-holding deficits and visual impairments. RESULTS: The features of CN varied even in patients from the same family. Head tilt, strabismus, reversal of optokinetic nystagmus, and impairments of the vestibulo-ocular reflex, smooth pursuits, and saccades were frequent findings. CONCLUSIONS: The intra- and interfamilial diversities imply that heredity plays a secondary role in determining the clinical phenotypes and waveforms of CN.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...