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1.
Int J Gen Med ; 17: 1909-1921, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38736671

RESUMO

Background: Dilated cardiomyopathy (DCM) is a severe heterogeneous cardiomyopathy characterized by cardiac enlargement and declining heart function, often leading to refractory heart failure and life-threatening outcomes, particularly prevalent in China. The challenge lies in the scarcity of targeted therapies with substantial efficacy for DCM. Additionally, traditional anti-heart failure drugs are constrained due to hypotension propensity or limited symptom improvement. Kuoxin Formula (KXF), internally endorsed at Longhua Hospital, demonstrates clear biological evidence for enhancing cardiac function and myocardial remodeling. Previous clinical studies suggest its potential to enhance patients' quality of life. This trial aims to further evaluate KXF's safety and efficacy in managing DCM-related heart failure. Methods: This prospective, randomized, double-blind, placebo-controlled, multicenter trial aims to recruit 230 DCM patients from five centers. Participants will be randomly assigned to either KXF or placebo for 12 weeks, with careful monitoring of key indicators and adverse events. The primary outcome measures the proportion of patients with NT-proBNP reduction exceeding 30%. Secondary outcomes include New York Heart Association functional classification, Traditional Chinese Medicine syndrome scores, 6-minute walk test, Lee's heart failure score, and Minnesota Heart Failure Quality of Life Scale score. Ventricular remodeling will be assessed using cardiac ultrasound and ELISA. Safety metrics and adverse events will be meticulously recorded. Discussion: This study will be the first multicentered research conducted in China that utilizes a randomized, double-blind, placebo-controlled design to investigate the use of TCM in the treatment of DCM. It seeks to develop new theoretical frameworks and provide solid clinical data to support the integration of TCM and modern medicine in treating heart failure in DCM patients. Trial Registration: China Clinical Trial Registry, ChiCTR2300068937. Registered on March 1, 2023. https://www.chictr.org.cn/bin/project/edit?pid=190926.

2.
Biosensors (Basel) ; 13(2)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36832000

RESUMO

Recently, infectious diseases, such as COVID-19, monkeypox, and Ebola, are plaguing human beings. Rapid and accurate diagnosis methods are required to preclude the spread of diseases. In this paper, an ultrafast polymerase chain reaction (PCR) equipment is designed to detect virus. The equipment consists of a silicon-based PCR chip, a thermocycling module, an optical detection module, and a control module. Silicon-based chip, with its thermal and fluid design, is used to improve detection efficiency. A thermoelectric cooler (TEC), together with a computer-controlled proportional-integral-derivative (PID) controller, is applied to accelerate the thermal cycle. A maximum of four samples can be tested simultaneously on the chip. Two kinds of fluorescent molecules can be detected by optical detection module. The equipment can detect viruses with 40 PCR amplification cycles in 5 min. The equipment is portable, easily operated, and low equipment cost, which shows great potential in epidemic prevention.


Assuntos
COVID-19 , Técnicas Analíticas Microfluídicas , Ácidos Nucleicos , Vírus , Humanos , Silício , Microfluídica , Reação em Cadeia da Polimerase/métodos , Ácidos Nucleicos/análise , Técnicas de Amplificação de Ácido Nucleico , Desenho de Equipamento
3.
Int J Biol Macromol ; 161: 223-230, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32512103

RESUMO

NCF/GO hybrid nanofillers with excellent UV-shielding properties were prepared by using TEMPO-oxidized nanocellulose fibrils (NCF) and graphene oxide (GO) as raw materials; different mass ratios of NCF to GO (2: 1, 4: 1, 8: 1, and 16: 1) were used. The NCF and GO were then combined and used as a hybrid filler to study the synergistic effects on polyvinyl alcohol (PVA) nanocomposites. With 5% hybrid nanofiller, the UV-shielding performance of the PVA/NCF/GO composite film was higher than 90%. The tensile strength and Young's modulus of the PVA/CG-2 composite film increased by 74.5% and 278.0%, respectively, and the water absorption decreased by 59%. Moreover, the thermal stabilities of the nanocomposites also improved. This synergistic effect improved the performance of the hybrid nanofiller by avoiding the agglomeration of nanofillers in the polymer matrix and improving the homogeneity of the dispersion. The synergistic effect between the fillers provides a new idea for the preparation of novel multifunctional nanocomposites.


Assuntos
Celulose/química , Grafite/química , Nanocompostos/química , Nanofibras/química , Álcool de Polivinil/química , Fenômenos Químicos , Fenômenos Mecânicos , Nanocompostos/ultraestrutura , Nanofibras/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Mol Metab ; 6(8): 863-872, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28752050

RESUMO

OBJECTIVE: Brown and white adipose tissue exerts pleiotropic effects on systemic energy metabolism in part by releasing endocrine factors. Neuregulin 4 (Nrg4) was recently identified as a brown fat-enriched secreted factor that ameliorates diet-induced metabolic disorders, including insulin resistance and hepatic steatosis. However, the physiological mechanisms through which Nrg4 regulates energy balance and glucose and lipid metabolism remain incompletely understood. The aims of the current study were: i) to investigate the regulation of adipose Nrg4 expression during obesity and the physiological signals involved, ii) to elucidate the mechanisms underlying Nrg4 regulation of energy balance and glucose and lipid metabolism, and iii) to explore whether Nrg4 regulates adipose tissue secretome gene expression and adipokine secretion. METHODS: We examined the correlation of adipose Nrg4 expression with obesity in a cohort of diet-induced obese mice and investigated the upstream signals that regulate Nrg4 expression. We performed metabolic cage and hyperinsulinemic-euglycemic clamp studies in Nrg4 transgenic mice to dissect the metabolic pathways regulated by Nrg4. We investigated how Nrg4 regulates hepatic lipid metabolism in the fasting state and explored the effects of Nrg4 on adipose tissue gene expression, particularly those encoding secreted factors. RESULTS: Adipose Nrg4 expression is inversely correlated with adiposity and regulated by pro-inflammatory and anti-inflammatory signaling. Transgenic expression of Nrg4 increases energy expenditure and augments whole body glucose metabolism. Nrg4 protects mice from diet-induced hepatic steatosis in part through activation of hepatic fatty acid oxidation and ketogenesis. Finally, Nrg4 promotes a healthy adipokine profile during obesity. CONCLUSIONS: Nrg4 exerts pleiotropic beneficial effects on energy balance and glucose and lipid metabolism to ameliorate obesity-associated metabolic disorders. Biologic therapeutics based on Nrg4 may improve both type 2 diabetes and non-alcoholic fatty liver disease (NAFLD) in patients.


Assuntos
Adipocinas/sangue , Ácidos Graxos/metabolismo , Neurregulinas/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo , Adipócitos/metabolismo , Animais , Células Cultivadas , Dieta Hiperlipídica/efeitos adversos , Metabolismo Energético , Glucose/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neurregulinas/genética , Hepatopatia Gordurosa não Alcoólica/etiologia , Obesidade/etiologia
5.
Angew Chem Int Ed Engl ; 56(20): 5561-5564, 2017 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-28394094

RESUMO

The importance of identifying DNA bases at the single-molecule level is well recognized for many biological applications. Although such identification can be achieved by electrical measurements using special setups, it is still not possible to identify single bases in real space by optical means owing to the diffraction limit. Herein, we demonstrate the outstanding ability of scanning tunneling microscope (STM)-controlled non-resonant tip-enhanced Raman scattering (TERS) to unambiguously distinguish two individual complementary DNA bases (adenine and thymine) with a spatial resolution down to 0.9 nm. The distinct Raman fingerprints identified for the two molecules allow to differentiate in real space individual DNA bases in coupled base pairs. The demonstrated ability of non-resonant Raman scattering with super-high spatial resolution will significantly extend the applicability of TERS, opening up new routes for single-molecule DNA sequencing.


Assuntos
Adenina/química , DNA/química , Análise Espectral Raman , Timina/química , Pareamento de Bases , Análise de Sequência de DNA
6.
Light Sci Appl ; 6(11): e17098, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30167216

RESUMO

Tip-enhanced Raman spectroscopy (TERS) is a powerful surface analysis technique that can provide subnanometer-resolved images of nanostructures with site-specific chemical fingerprints. However, due to the limitation of weak Raman signals and the resultant difficulty in achieving TERS imaging with good signal-to-noise ratios (SNRs), the conventional single-peak analysis is unsuitable for distinguishing complex molecular architectures at the subnanometer scale. Here we demonstrate that the combination of subnanometer-resolved TERS imaging and advanced multivariate analysis can provide an unbiased panoramic view of the chemical identity and spatial distribution of different molecules on surfaces, yielding high-quality chemical images despite limited SNRs in individual pixel-level spectra. This methodology allows us to exploit the full power of TERS imaging and unambiguously distinguish between adjacent molecules with a resolution of ~0.4 nm, as well as to resolve submolecular features and the differences in molecular adsorption configurations. Our results provide a promising methodology that promotes TERS imaging as a routine analytical technique for the analysis of complex nanostructures on surfaces.

7.
Nano Lett ; 16(7): 4040-6, 2016 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-27348072

RESUMO

Individual carbon nanotubes (CNTs) have been investigated by tip-enhanced Raman spectroscopy (TERS) using silver tips on the Ag(111) substrate with a low-temperature ultrahigh-vacuum scanning tunneling microscope. Thanks to the strong and highly localized plasmonic field offered by the silver nanogap, the spatial resolution of TERS on CNTs is driven down to about 0.7 nm. Such a high spatial resolution allows to visualize in real space the spatial extent of the defect-induced D-band scattering, to track the strain-induced spectral evolution, and to resolve the spectral differences between the inner and the outer sides of a bent CNT, all at the nanometer scale.

8.
PLoS One ; 10(10): e0140752, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26485435

RESUMO

Dendritic spines undergo continuous remodeling during development of the nervous system. Their stability is essential for maintaining a functional neuronal circuit. Spine dynamics and stability of cortical excitatory pyramidal neurons have been explored extensively in mammalian animal models. However, little is known about spiny interneurons in non-mammalian vertebrate models. In the present study, neuronal morphology was visualized by single-cell electroporation. Spiny neurons were surveyed in the Xenopus tadpole brain and observed to be widely distributed in the olfactory bulb and telencephalon. DsRed- or PSD95-GFP-expressing spiny interneurons in the olfactory bulb were selected for in vivo time-lapse imaging. Dendritic protrusions were classified as filopodia, thin, stubby, or mushroom spines based on morphology. Dendritic spines on the interneurons were highly dynamic, especially the filopodia and thin spines. The stubby and mushroom spines were relatively more stable, although their stability significantly decreased with longer observation intervals. The 4 spine types exhibited diverse preferences during morphological transitions from one spine type to others. Sensory deprivation induced by severing the olfactory nerve to block the input of mitral/tufted cells had no significant effects on interneuron spine stability. Hence, a new model was established in Xenopus laevis tadpoles to explore dendritic spine dynamics in vivo.


Assuntos
Espinhas Dendríticas/fisiologia , Interneurônios/fisiologia , Plasticidade Neuronal/fisiologia , Bulbo Olfatório/fisiologia , Animais , Feminino , Interneurônios/citologia , Larva , Bulbo Olfatório/citologia , Imagem com Lapso de Tempo , Xenopus laevis
9.
Nat Nanotechnol ; 10(10): 865-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26214250

RESUMO

Unambiguous chemical identification of individual molecules closely packed on a surface can offer the possibility to address single chemical species and monitor their behaviour at the individual level. Such a degree of spatial resolution can in principle be achieved by detecting their vibrational fingerprints using tip-enhanced Raman scattering (TERS). The chemical specificity of TERS can be combined with the high spatial resolution of scanning probe microscopy techniques, an approach that has stimulated extensive research in the field. Recently, the development of nonlinear TERS in a scanning tunnelling microscope has pushed the spatial resolution down to ∼0.5 nm, allowing the identification of the vibrational fingerprints of isolated molecules on Raman-silent metal surfaces. Although the nonlinear TERS component is likely to help sharpen the optical contrast of the acquired image, the TERS signal still contains a considerable contribution from the linear term, which is spatially less confined. Therefore, in the presence of different adjacent molecules, a mixing of Raman signals may result. Here, we show that using a nonlinear scanning tunnelling microscope-controlled TERS set-up, two different adjacent molecules that are within van der Waals contact and of very similar chemical structure (a metal-centred porphyrin and a free-base porphyrin) on a silver surface can be distinguished in real space. In addition, with the help of density functional theory simulations, we are also able to determine their adsorption configurations and orientations on step edges and terraces.

10.
J Biomed Opt ; 19(8): 086005, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25104411

RESUMO

The myelin sheath plays an important role as the axon in the functioning of the neural system, and myelin degradation is a hallmark pathology of multiple sclerosis and spinal cord injury. Electron microscopy, fluorescent microscopy, and magnetic resonance imaging are three major techniques used for myelin visualization. However, microscopic observation of myelin in living organisms remains a challenge. Using a newly developed stimulated Raman scattering microscopy approach, we report noninvasive, label-free, real-time in vivo imaging of myelination by a single-Schwann cell, maturation of a single node of Ranvier, and myelin degradation in the transparent body of the Xenopus laevis tadpole.


Assuntos
Aumento da Imagem/instrumentação , Microscopia/instrumentação , Bainha de Mielina/ultraestrutura , Fibras Nervosas Mielinizadas/ultraestrutura , Análise Espectral Raman/instrumentação , Animais , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Xenopus laevis
11.
Diabetes ; 63(4): 1340-52, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24379350

RESUMO

Chronic low-grade inflammation is emerging as a pathogenic link between obesity and metabolic disease. Persistent immune activation in white adipose tissue (WAT) impairs insulin sensitivity and systemic metabolism, in part, through the actions of proinflammatory cytokines. Whether obesity engages an adaptive mechanism to counteract chronic inflammation in adipose tissues has not been elucidated. Here we identified otopetrin 1 (Otop1) as a component of a counterinflammatory pathway that is induced in WAT during obesity. Otop1 expression is markedly increased in obese mouse WAT and is stimulated by tumor necrosis factor-α in cultured adipocytes. Otop1 mutant mice respond to high-fat diet with pronounced insulin resistance and hepatic steatosis, accompanied by augmented adipose tissue inflammation. Otop1 attenuates interferon-γ (IFN-γ) signaling in adipocytes through selective downregulation of the transcription factor STAT1. Using a tagged vector, we found that Otop1 physically interacts with endogenous STAT1. Thus, Otop1 defines a unique target of cytokine signaling that attenuates obesity-induced adipose tissue inflammation and plays an adaptive role in maintaining metabolic homeostasis in obesity.


Assuntos
Tecido Adiposo/patologia , Inflamação/prevenção & controle , Proteínas de Membrana/farmacologia , Obesidade/metabolismo , Tecido Adiposo Branco/metabolismo , Animais , Dieta Hiperlipídica , Homeostase/efeitos dos fármacos , Inflamação/imunologia , Resistência à Insulina/fisiologia , Interferon gama/efeitos dos fármacos , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Fator de Transcrição STAT1/metabolismo
12.
Angew Chem Int Ed Engl ; 52(49): 13042-6, 2013 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-24127161

RESUMO

A finger on the pulse: Current molecular analysis of cells and tissues routinely relies on separation, enrichment, and subsequent measurements by various assays. Now, a platform of hyperspectral stimulated Raman scattering microscopy has been developed for the fast, quantitative, and label-free imaging of biomolecules in intact tissues using spectroscopic fingerprints as the contrast mechanism.


Assuntos
Colesterol/química , Análise Espectral Raman/métodos , Análise Serial de Tecidos/métodos , Artérias/química , Aterosclerose/patologia , Colesterol/análise , Humanos
13.
Mol Endocrinol ; 27(10): 1643-54, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23960084

RESUMO

Nonalcoholic fatty liver disease is a metabolic disorder commonly associated with obesity. A subset of nonalcoholic fatty liver disease patients further develops nonalcoholic steatohepatitis that is characterized by chronic liver injury, inflammation, and fibrosis. Recent work has implicated the autophagy pathway in the mobilization and oxidation of triglycerides from lipid droplets. However, whether impaired autophagy in hepatocytes drives excess fat accumulation in the liver remains controversial. In addition, the role of autophagy in protecting the liver from gut endotoxin-induced injury has not been elucidated. Here we generated mice with liver-specific autophagy deficiency by the conditional deletion of focal adhesion kinase family kinase-interacting protein of 200 kDa (also called Rb1cc1), a core subunit of the mammalian autophagy related 1 complex. To our surprise, mice lacking FIP200 in hepatocytes were protected from starvation- and high-fat diet-induced fat accumulation in the liver and had decreased expression of genes involved in lipid metabolism. Activation of the de novo lipogenic program by liver X receptor was impaired in FIP200-deficient livers. Furthermore, liver autophagy was stimulated by exposure to low doses of lipopolysaccharides and its deficiency-sensitized mice to endotoxin-induced liver injury. Together these studies demonstrate that hepatocyte-specific autophagy deficiency per se does not exacerbate hepatic steatosis. Instead, autophagy may play a protective role in the liver after exposure to gut-derived endotoxins and its blockade may accelerate nonalcoholic steatohepatitis progression.


Assuntos
Autofagia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Fígado Gorduroso/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Animais , Proteínas Relacionadas à Autofagia , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Dieta Hiperlipídica/efeitos adversos , Fígado Gorduroso/genética , Fígado Gorduroso/patologia , Regulação da Expressão Gênica , Hepatócitos/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Lipogênese/genética , Lipopolissacarídeos/farmacologia , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Receptores X do Fígado , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica , Receptores Nucleares Órfãos/fisiologia , Triglicerídeos/metabolismo
14.
Opt Lett ; 38(9): 1479-81, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23632524

RESUMO

We demonstrate a low-cost-stimulated Raman scattering (SRS) microscope using continuous-wave (cw) lasers as excitation sources. A dual modulation scheme is used to remove the electronic background. The cw-SRS imaging of lipids in fatty liver is demonstrated by excitation of C─H stretch vibration.


Assuntos
Lasers , Imagem Molecular/métodos , Análise Espectral Raman , Fígado Gorduroso/patologia , Microscopia
15.
J Vis Exp ; (36)2010 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-20125082

RESUMO

Optokinetic response (OKR) is a behavior that an animal vibrates its eyes to follow a rotating grating around it. It has been widely used to assess the visual functions of larval zebrafish. Nevertheless, the standard protocol for larval fish is not yet readily applicable in adult zebrafish. Here, we introduce how to measure the OKR of adult zebrafish with our simple custom-built apparatus using a new protocol which is established in our lab. Both our apparatus and step-by-step procedure of OKR in adult zebrafish are illustrated in this video. In addition, the measurements of the larval OKR, as well as the optomotor response (OMR) test of adult zebrafish, are also demonstrated in this video. This OKR assay of adult zebrafish in our experiment may last for up to 4 hours. Such OKR test applied in adult fish will benefit to visual function investigation more efficiently when the adult fish vision system is manipulated.


Assuntos
Medições dos Movimentos Oculares/instrumentação , Nistagmo Optocinético/fisiologia , Peixe-Zebra/fisiologia , Animais
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