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1.
Proc Natl Acad Sci U S A ; 120(10): e2207461120, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36848577

RESUMO

The composition of the plasma membrane (PM) must be tightly controlled despite constant, rapid endocytosis, which requires active, selective recycling of endocytosed membrane components. For many proteins, the mechanisms, pathways, and determinants of this PM recycling remain unknown. We report that association with ordered, lipid-driven membrane microdomains (known as rafts) is sufficient for PM localization of a subset of transmembrane proteins and that abrogation of raft association disrupts their trafficking and leads to degradation in lysosomes. Using orthogonal, genetically encoded probes with tunable raft partitioning, we screened for the trafficking machinery required for efficient recycling of engineered microdomain-associated cargo from endosomes to the PM. Using this screen, we identified the Rab3 family as an important mediator of PM localization of microdomain-associated proteins. Disruption of Rab3 reduced PM localization of raft probes and led to their accumulation in Rab7-positive endosomes, suggesting inefficient recycling. Abrogation of Rab3 function also mislocalized the endogenous raft-associated protein Linker for Activation of T cells (LAT), leading to its intracellular accumulation and reduced T cell activation. These findings reveal a key role for lipid-driven microdomains in endocytic traffic and suggest Rab3 as a mediator of microdomain recycling and PM composition.


Assuntos
Endocitose , Proteínas de Membrana , Membrana Celular , Movimento Celular , Lipídeos , Proteínas rab3 de Ligação ao GTP/metabolismo
2.
J Magn Reson Imaging ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38544434

RESUMO

BACKGROUND: The fasting-postprandial state remains an underrecognized confounding factor for quantifying cerebral blood flow (CBF) in the cognitive assessment and differential diagnosis of Alzheimer's disease (AD). PURPOSE: To investigate the effects of fasting-postprandial state on arterial spin labeling (ASL)-based CBF in AD patients. STUDY TYPE: Prospective. SUBJECTS: Ninety-two subjects (mean age = 62.5 ± 6.4 years; females 29.3%), including 30 with AD, 32 with mild cognitive impairment (MCI), and 30 healthy controls (HCs). Differential diagnostic models were developed with a 4:1 training to testing set ratio. FIELD STRENGTH/SEQUENCE: 3-T, T1-weighted imaging using gradient echo and pseudocontinuous ASL imaging using turbo spin echo. ASSESSMENT: Two ASL scans were acquired to quantify fasting state and postprandial state regional CBFs based on an automated anatomical labeling atlas. Two-way ANOVA was used to assess the effects of fasting/postprandial state and disease state (AD, MCI, and HC) on regional CBF. Pearson's correlation analysis was conducted between regional CBF and cognitive scores (Mini-Mental State Examination [MMSE] and Montreal Cognitive Assessment [MoCA]). The diagnostic performances of the fasting state, postprandial state, and mixed state (random mixing of the fasting and postprandial state CBF) in differential diagnosis of AD were conducted using support vector machine and logistic regression models. STATISTICAL TESTS: Two-way ANOVA, Pearson's correlation, and area under the curve (AUC) of diagnostic model were performed. P values <0.05 indicated statistical significance. RESULTS: Fasting-state CBF was correlated with cognitive scores in more brain regions (17 vs. 4 [MMSE] and 15 vs. 9 [MoCA]) and had higher absolute correlation coefficients than postprandial-state CBF. In the differential diagnosis of AD patients from MCI patients and HCs, fasting-state CBF outperformed mixed-state CBF, which itself outperformed postprandial-state CBF. DATA CONCLUSION: Compared with postprandial CBF, fasting-state CBF performed better in terms of cognitive score correlations and in differentiating AD patients from MCI patients and HCs. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 3.

3.
Neurocrit Care ; 40(1): 282-291, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36991176

RESUMO

BACKGROUND: Although abnormal heart rate variability (HRV) is frequently observed in patients with spontaneous intracerebral hemorrhage (ICH), its time course and presentation of different indices remain unclear, and few studies have focused on its association with clinical outcomes. METHODS: We prospectively recruited consecutive patients with spontaneous ICH between June 2014 and June 2021. HRV was evaluated twice during hospitalization (within 7 days and 10-14 days after stroke). Time and frequency domain indices were calculated. A modified Rankin Scale score ≥ 3 at 3 months was defined as a poor outcome. RESULTS: Finally, 122 patients with ICH and 122 age- and sex-matched volunteers were included. Compared with controls, time domain and absolute frequency domain HRV parameters (total power, low frequency [LF], and high frequency [HF]) in the ICH group were significantly decreased within 7 days and 10-14 days. For relative values, normalized LF (LF%) and LF/HF were significantly higher, whereas normalized HF (HF%) was significantly lower, in the patient group than in the control group. Furthermore, LF% and HF% measured at 10-14 days were independently associated with 3-month outcomes. CONCLUSIONS: HRV values were impaired significantly within 14 days after ICH. Furthermore, HRV indices measured 10-14 days after ICH were independently associated with 3-month outcomes.


Assuntos
Hemorragia Cerebral , Acidente Vascular Cerebral , Humanos , Frequência Cardíaca/fisiologia , Arritmias Cardíacas , Hospitalização
4.
Molecules ; 28(12)2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37375139

RESUMO

Six compounds including three new benzophenones, selagibenzophenones D-F (1-3), two known selaginellins (4-5) and one known flavonoid (6), were isolated from Selaginella tamariscina. The structures of new compounds were established by 1D-, 2D-NMR and HR-ESI-MS spectral analyses. Compound 1 represents the second example of diarylbenzophenone from natural sources. Compound 2 possesses an unusual biphenyl-bisbenzophenone structure. Their cytotoxicity against human hepatocellular carcinoma HepG2 and SMCC-7721 cells and inhibitory activities on lipopolysaccharide-induced nitric oxide (NO) production in RAW264.7 cells were evaluated. Compound 2 showed moderate inhibitory activity against HepG2 and SMCC-7721 cells, and compounds 4 and 5 showed moderate inhibitory activity to HepG2 cells. Compounds 2 and 5 also exhibited inhibitory activities on lipopolysaccharide-induced nitric oxide (NO) production.


Assuntos
Selaginellaceae , Humanos , Estrutura Molecular , Selaginellaceae/química , Óxido Nítrico , Lipopolissacarídeos/farmacologia , Benzofenonas/farmacologia
5.
Epidemiol Infect ; 149: e94, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33845928

RESUMO

The global outbreak of coronavirus disease 2019 (COVID-19) is greatly threatening the public health in the world. We reconstructed global transmissions and potential demographic expansions of severe acute respiratory syndrome coronavirus 2 based on genomic information. We found that intercontinental transmissions were rare in January and early February but drastically increased since late February. After world-wide implements of travel restrictions, the transmission frequencies decreased to a low level in April. We identified a total of 88 potential demographic expansions over the world based on the star-radiative networks and 75 of them were found in Europe and North America. The expansion numbers peaked in March and quickly dropped since April. These findings are highly concordant with epidemic reports and modelling results and highlight the significance of quarantine validity on the global spread of COVID-19. Our analyses indicate that the travel restrictions and social distancing measures are effective in containing the spread of COVID-19.


Assuntos
COVID-19/epidemiologia , Genoma Viral , Política Pública , SARS-CoV-2/genética , Viagem , África/epidemiologia , Ásia/epidemiologia , Austrália/epidemiologia , COVID-19/transmissão , COVID-19/virologia , Controle de Doenças Transmissíveis , Europa (Continente)/epidemiologia , Genômica , Humanos , Internacionalidade , América do Norte/epidemiologia , Filogenia , Distanciamento Físico , América do Sul/epidemiologia
6.
Environ Monit Assess ; 193(6): 321, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33945020

RESUMO

One hundred forty-three surface sediment (0-5 cm depth) samples were collected from locations representing industrialized areas, less-industrialized areas, and e-waste recycling areas in the Pearl River Delta (PRD). The spatial distribution of polychlorinated biphenyls (PCBs) and their potential adverse effects on aquatic organisms were investigated. The average PCB concentration in the less-industrialized areas (background) in the PRD was approximately 10 ng/g dry weight (dw), which was generally half that found in the industrialized areas (approximately 22 ng/g dw). Severe PCB contamination, with concentrations ranging from 1000 to 26500 ng/g dw, was found in pond sediments collected from e-waste recycling areas. It is very likely that such contamination would have had adverse effects on the aquatic biota there. PCBs in the e-waste recycling areas were dominated by penta- and hex-PCB congeners, which made them significantly different from those found in other regions, where tri- and tetra-PCB congeners were predominant. Higher abundances of less chlorinated congeners were seen in the less-industrialized areas compared to the industrialized areas. Differences in the transport abilities of different congeners, together with dechlorination of higher chlorinated congeners, is the most likely reasons for this.


Assuntos
Bifenilos Policlorados , Rios , China , Monitoramento Ambiental , Sedimentos Geológicos , Bifenilos Policlorados/análise
7.
Langmuir ; 36(39): 11637-11644, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32902987

RESUMO

Many noble metal-based nanoparticles have emerged for applications in cancer radiotherapy in recent years, but few investigations have been carried out for palladium nanoparticles. Herein, palladium nanosheets (Pd NSs), which possess a sheetlike morphology with a diameter of ∼14 nm and a thickness of ∼2 nm, were utilized as a sensitizer to improve the performance of radiotherapy. It was found that Pd NSs alone did not decrease the cell viability after treatment for as long as 130 h, suggesting the excellent cytocompatibility of the nanoagents. However, the viability of cancer cells treated with X-ray irradiation became lower, and the viability became even lower if the cells were co-treated with X-ray and Pd NSs, indicating the radiosensitization effect of Pd NSs. Additionally, compared with X-ray irradiation, the combined treatment of Pd NSs and X-ray irradiation induced the generation of more DNA double-stranded breaks and reactive oxygen species within cancer cells, which eventually caused elevated cell apoptosis. Moreover, in vivo experiments also verified the radiosensitization effect and the favorable biocompatibility of Pd NSs, indicating their potential for acquiring satisfactory in vivo radiotherapeutic effect at lower X-ray doses. It is believed that the present research will open new avenues for the application of noble metal-based nanoparticles in radiosensitization.


Assuntos
Nanopartículas Metálicas , Radiossensibilizantes , Apoptose , Sobrevivência Celular , Nanopartículas Metálicas/toxicidade , Paládio , Radiossensibilizantes/toxicidade
8.
Heart Surg Forum ; 23(5): E636-E640, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32990582

RESUMO

OBJECTIVE: This study was aimed to elucidate the feasibility of using right ventricular (RV) strain and strain rate to evaluate right heart function of Ebstein anomaly (EA) patients before and after operation. METHODS: Sixty EA patients and 30 healthy controls underwent echocardiography (UCG) for evaluation of right heart function. Preoperative UCG and 1-week and 3-month postoperative UCG were performed in EA patients. RV strain and strain rate were measured on the four-chamber section of tissue Doppler imaging (TDI). RESULTS: The strain and strain rate representative of right ventricle systolic function were reduced prior to operation. RV strain and strain rate improved after the operation (P < .001), most significantly in the basal segment and middle segment of the free wall of the right ventricle as well as the basal segment of the interventricular septum (P < .001). CONCLUSIONS: The measurement of RV strain and strain rate on tissue Doppler imaging can be employed to assess the preoperative and postoperative RV function, proves the positive effect of tricuspid valve repair on right heart function, and offers more insight on right heart function evaluation.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Anomalia de Ebstein/fisiopatologia , Ventrículos do Coração/fisiopatologia , Contração Miocárdica/fisiologia , Função Ventricular Direita/fisiologia , Adolescente , Anomalia de Ebstein/diagnóstico , Anomalia de Ebstein/cirurgia , Ecocardiografia Doppler/métodos , Feminino , Seguimentos , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Período Pós-Operatório , Estudos Retrospectivos , Sístole , Adulto Jovem
9.
Opt Express ; 27(21): 29863-29874, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684242

RESUMO

Orbital angular momentum (OAM) light is nowadays an intriguing resource in classical and quantum optics due to the richness of physical properties it shows in interaction with matter. A key ingredient needed to exploit the full potential of OAM light is the control of quantum interference, a crucial resource in fields like quantum communication and quantum optics. Here, we study the vortex four-wave mixing (FWM) via multi-photon quantum interference in an ultraslow propagation regime. We find that the structured information can be manipulated via two-photon detuning and three photon detuning, which manifests itself as a spatial modulation. The detailed explanations based on the dispersion relation are given, which are in good agreement with our simulations. Furthermore, in order to clearly show the modulated mechanism, we perform the interference between the FWM field and a same-frequency Gaussian beam. It is found that the interference patterns are also manipulated by adjusting the multi-photon detunings. This work may have some potential applications in quantum control based on OAM light.

10.
Nano Lett ; 18(2): 1159-1167, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29368935

RESUMO

Water-dispersible nanomaterials with superbright photoluminescence (PL) emissions and narrow PL bandwidths are urgently desired for various imaging applications. Herein, for the first time, we prepared ultrasmall organosilica nanodots (OSiNDs) with an average size of ∼2.0 nm and ∼100% green-emitting PL quantum efficiency via a one-step hydrothermal treatment of two commercial reagents (a silane molecule and rose bengal). In particular, the structural reorganization and halide loss of rose bengal during the hydrothermal treatment contribute to the ultrahigh quantum yield and low phototoxicity of OSiNDs. Owing to their low pH-induced precipitation/aggregation property, the as-prepared OSiNDs can be used as excellent lysosomal trackers with many advantages: (1) They have superior lysosomal targeting ability with a Pearson's coefficient of 0.98; (2) The lysosomal monitoring time of OSiNDs is up to 48 h, which is much longer than those of commercial lysosomal trackers (<2 h); (3) They do not disturb the pH environment of lysosomes and can be used to visualize lysosomes in living, fixed, and permeabilized cells; (4) They exhibit intrinsic lysosomal tracking ability without the introduction of lysosome-targeting ligands (such as morpholine) and superior photostability; (5) The easy, cost-effective, and scalable synthetic method further ensures that these OSiNDs can be readily used as exceptional lysosomal trackers. We expect that the ultrasmall OSiNDs with superior fluorescence properties and easily modifiable surfaces could be applied as fluorescent nanoprobes, light-emitting diode phosphor, and anticounterfeiting material, which should be able to promote the preparation and application of silicon-containing nanomaterials.


Assuntos
Substâncias Luminescentes/química , Lisossomos/ultraestrutura , Compostos de Organossilício/química , Pontos Quânticos/química , Células A549 , Humanos , Concentração de Íons de Hidrogênio , Luminescência , Lisossomos/química , Microscopia Confocal/métodos , Modelos Moleculares , Imagem Óptica/métodos , Permeabilidade , Fixação de Tecidos
11.
Bioconjug Chem ; 29(4): 1194-1198, 2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29498825

RESUMO

Nitric oxide (NO) is a versatile endogenous molecule, involved in various physiological processes and implicated in the progression of many pathological conditions. Therefore, NO donors are valuable tools in NO related basic and applied applications. The traditional spontaneous NO donors are limited in scenarios where flux, localization, and dose of NO could be monitored. This has promoted the development of novel NO donors, whose NO release is not only under control, but also self-calibrated. Herein, we reported a phototriggered and photocalibrated NO donor (NOD565) with an N-nitroso group on a rhodamine dye. NOD565 is nonfluorescent and could release NO efficiently upon irradiation by green light. A bright rhodamine dye is generated as a side-product and its fluorescence can be used to monitor the NO release. The potentials of NOD565 in practical applications are showcased in in vitro studies, e.g., platelet aggregation inhibition and fungi growth suppression.


Assuntos
Doadores de Óxido Nítrico/química , Doadores de Óxido Nítrico/farmacologia , Processos Fotoquímicos , Raios Ultravioleta , Anti-Infecciosos/farmacologia , Calibragem , Fluorescência , Óxido Nítrico/química , Inibidores da Agregação Plaquetária/farmacologia , Rodaminas/química , Solubilidade , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Água/química
12.
Phys Chem Chem Phys ; 20(48): 30428-30436, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30499999

RESUMO

Chiral differentiation of protonated isoleucine (Ile) using permethylated ß-cyclodextrin (perCD) in the gas-phase was studied using infrared multiple photon dissociation (IRMPD) spectroscopy, ion-mobility, and density functional theory (DFT) calculations. The gaseous protonated non-covalent complexes of perCD and d-Ile or l-Ile produced by electrospray ionization were interrogated by laser pulses in the wavenumber region of 2650 to 3800 cm-1. The IRMPD spectra showed remarkably different IR spectral features for the d-Ile or l-Ile and perCD non-covalent complexes. However, drift-tube ion-mobility experiments provided only a small difference in their collision cross-sections, and thus a limited separation of the d- and l-Ile complexes. DFT calculations revealed that the chiral distinction of the d- and l-complexes by IRMPD spectroscopy resulted from local interactions of the protonated Ile with perCD. Furthermore, the theoretical results showed that the IR absorption spectra of higher energy conformers (by ∼13.7 kcal mol-1) matched best with the experimentally observed IRMPD spectra. These conformers are speculated to be formed from kinetic-trapping of the solution-phase conformers. This study demonstrated that IRMPD spectroscopy provides an excellent platform for differentiating the subtle chiral difference of a small amino acid in a cyclodextrin-complexation environment; however, drift-tube ion-mobility did not have sufficient resolution to distinguish the chiral difference.

13.
Hepatobiliary Pancreat Dis Int ; 17(6): 496-501, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30205926

RESUMO

BACKGROUND: Body temperature is poorly regulated in patients with end-stage liver disease. Due to the prolonged surgery time and anhepatic time as well as the complex surgical procedures performed in liver transplantation, the body temperature fluctuates greatly. This study investigated the effect of intraoperative body temperature fluctuations on the prognosis of liver recipients. METHODS: The body temperatures of liver recipients recorded from the induction of anesthesia (T0) until the end of surgery (T14) were retrieved. The patients were divided into two groups: the hypothermia group (< 35 °C and ≥ 5 min) and the normothermia group (≥ 35 °C or < 35 °C but < 5 min). Intraoperative and postoperative variables were compared between the two groups, and the correlations between the duration of hypothermia and the medical variables were analyzed. RESULTS: Of the 107 patients, 67 patients were in the normothermia group, and 40 in the hypothermia group. The lowest body temperature was at 5 min after reperfusion for the whole cohort. Compared with the normothermia group, patients in the hypothermia group were more prone to bleeding, had a longer intubation time and increased rates of bacterial infection and acute pulmonary edema after liver transplantation (P < 0.05). Hypothermia time was positively correlated with bleeding volume, intubation time, units of blood transfusions and intensive care stay, but negatively correlated with urine output. CONCLUSIONS: The intraoperative body temperature exhibited a graphical "V" trend, and the lowest temperature was at 5 min after reperfusion. The longer the duration of hypothermia, the more unfavourable the prognosis.


Assuntos
Temperatura Corporal , Transplante de Fígado , Adulto , Feminino , Humanos , Hipotermia/complicações , Período Intraoperatório , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Tempo
14.
Arch Psychiatr Nurs ; 32(2): 224-228, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29579516

RESUMO

Quality of life (QOL) throughout menopause has become an outcome variable requiring measurement in clinical care. Staff nurses can provide earlier nursing during the menopausal transition (MT) stage. The purpose of this study was to describe the changes of QOL in different stages of the MT according to The Stages of Reproductive Aging Workshop (STRAW) in Chinese women in community settings. Prospective longitudinal study design was used to analyze QOL of 327 community women age 30-65years old. They were followed up at 1-year. An instrument including the Chinese version of the Menopause-Specific Quality of Life Questionnaire was used to obtain data. A gradual decline in QOL was seen from premenopausal to menopausal transition (MT) and in postmenopausal women. Significant differences were observed in vasomotor, physical and sexual scores at baseline and follow-up (P<0.05). Significant differences in vasomotor scores were observed between baseline and follow-up for women in the premenopausal and Late MT stages (P<0.05). There were significant differences in psychosocial and physical scores between baseline and follow-up in the Late MT stage (P<0.05). Menopause might have a negative impact on QOL independent of age in community-based women in China. There seemed to be a potential model of the relationship of menopause status to change in QOL, but this needs supporting evidence from longer longitudinal studies.


Assuntos
Povo Asiático/estatística & dados numéricos , Vida Independente , Menopausa/psicologia , Qualidade de Vida/psicologia , Adulto , Povo Asiático/psicologia , China , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários
15.
Phys Chem Chem Phys ; 19(22): 14729-14737, 2017 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28540941

RESUMO

The gaseous chiral differentiation of alanine by permethylated ß-cyclodextrin was studied using IRMPD spectroscopy and density functional theory calculations. The protonated non-covalent complexes of permethylated ß-cyclodextrin and d- or l-alanine were mass-selected and investigated by IR laser pulses in the wavelength region of 2650-3800 cm-1. The remarkably different features of the IRMPD spectra for d- and l-alanine are described, and their origin is elucidated by quantum chemical calculations. We show that the differentiation of the experimentally observed spectral features is the result of different local interactions of d- and l-alanine with permethylated ß-cyclodextrin. We also assign the extremely high-frequency (>3700 cm-1) bands in the observed spectra to the stretch motions of completely isolated alanine -OH groups.

16.
Artigo em Inglês | MEDLINE | ID: mdl-29024237

RESUMO

Insects cannot synthesize sterols and must obtain them from plants. Therefore, reducing plant sterol content or changing sterol type might be an effective pest control strategy. However, the impacts of these changes on pests' natural predators remain unknown. Here, we fed artificial diets with reduced sterol content to Mythimna separata (Walker) (Lepidoptera: Noctuidae) and investigated the effects on its natural predator, Arma chinensis (Fallou) (Hemiptera: Pentatomidae). Reduced sterol content in M. separata (MS1, MS2, and MS5) was achieved by feeding them artificial diets prepared from a feed base subjected to one, two, or five cycles of sterol extractions, respectively. The content of most substances increased in A. chinensis (AC) groups feeding on MS2 and MS5. The content of eight substances (alanine, betaine, dimethylamine, fumarate, glutamine, glycine, methylamine, and sarcosine) differed significantly between the control (AC0) and treated (AC1, AC2, and AC5) groups. Metabolic profiling revealed that only AC5 was significantly distinct from AC0; the major substances contributing to this difference were maltose, glucose, tyrosine, proline, O-phosphocholine, glutamine, allantoin, lysine, valine, and glutamate. Furthermore, only two metabolic pathways, that is, nicotinate and nicotinamide metabolism and ubiquinone and other terpenoid-quinone biosynthesis, differed significantly between AC1 and AC5 and the control, albeit with an impact value of zero. Thus, the sterol content in the artificial diet fed to M. separata only minimally affected the metabolites and metabolic pathways of its predator A. chinensis, suggesting that A. chinensis has good metabolic self-regulation with high resistance to sterol content changes.


Assuntos
Cadeia Alimentar , Hemípteros/metabolismo , Mariposas , Fitosteróis/administração & dosagem , Animais , Produtos Agrícolas , Dieta , Metaboloma , Plantas Geneticamente Modificadas , Espectroscopia de Prótons por Ressonância Magnética
17.
Pediatr Cardiol ; 38(1): 199-201, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27885444

RESUMO

A dying neonate with congenital complete atrioventricular block underwent an emergency temporary pacing via the umbilical vein 1 h after birth. Implantation of a permanent epicardial pacemaker system was performed at the age of 10 days. During the follow-up period of 3 months, the child had been growing well with the VVIR pacemaker.


Assuntos
Estimulação Cardíaca Artificial/métodos , Tratamento de Emergência/métodos , Bloqueio Cardíaco/congênito , Eletrocardiografia , Bloqueio Cardíaco/terapia , Humanos , Lactente , Recém-Nascido , Masculino , Marca-Passo Artificial , Veias Umbilicais/cirurgia
18.
Bioconjug Chem ; 27(3): 782-9, 2016 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-26829525

RESUMO

Long-time stable plasma membrane imaging is difficult due to the fast cellular internalization of fluorescent dyes and the quick detachment of the dyes from the membrane. In this study, we developed a two-step synergistic cell surface modification and labeling strategy to realize long-time plasma membrane imaging. Initially, a multisite plasma membrane anchoring reagent, glycol chitosan-10% PEG2000 cholesterol-10% biotin (abbreviated as "GC-Chol-Biotin"), was incubated with cells to modify the plasma membranes with biotin groups with the assistance of the membrane anchoring ability of cholesterol moieties. Fluorescein isothiocyanate (FITC)-conjugated avidin was then introduced to achieve the fluorescence-labeled plasma membranes based on the supramolecular recognition between biotin and avidin. This strategy achieved stable plasma membrane imaging for up to 8 h without substantial internalization of the dyes, and avoided the quick fluorescence loss caused by the detachment of dyes from plasma membranes. We have also demonstrated that the imaging performance of our staining strategy far surpassed that of current commercial plasma membrane imaging reagents such as DiD and CellMask. Furthermore, the photodynamic damage of plasma membranes caused by a photosensitizer, Chlorin e6 (Ce6), was tracked in real time for 5 h during continuous laser irradiation. Plasma membrane behaviors including cell shrinkage, membrane blebbing, and plasma membrane vesiculation could be dynamically recorded. Therefore, the imaging strategy developed in this work may provide a novel platform to investigate plasma membrane behaviors over a relatively long time period.


Assuntos
Fluoresceína-5-Isotiocianato/química , Membrana Celular/metabolismo
19.
Langmuir ; 32(39): 10126-10135, 2016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27597442

RESUMO

Cholesterol-containing molecules or nanoparticles play a significant role in achieving favorable plasma membrane imaging and efficient cellular uptake of drugs by the excellent membrane anchoring capability of the cholesterol moiety. By linking cholesterol to a water-soluble component (such as poly(ethylene glycol), PEG), the resulting cholesterol-PEG conjugate can form micelles in aqueous solution through self-assembly, and such a micellar structure represents an important drug delivery vehicle in which hydrophobic drugs can be encapsulated. However, the understanding of the subcellular fate and cytotoxicity of cholesterol-PEG conjugates themselves remains elusive. Herein, by using cholesterol-PEG2000-fluorescein isothiocyanate (Chol-PEG-FITC) as a model system, we found that the Chol-PEG-FITC molecules could attach to the plasma membranes of mammalian cells within 10 min and such a firm membrane attachment could last at least 1 h, displaying excellent plasma membrane staining performance that surpassed that of commonly used commercial membrane dyes such as DiD and CellMask. Besides, we systematically studied the endocytosis pathway and intracellular distribution of Chol-PEG-FITC and found that the cell surface adsorption and endocytosis processes of Chol-PEG-FITC molecules were lipid-raft-dependent. After internalization, the Chol-PEG-FITC molecules gradually reached many organelles with membrane structures. At 5 h, they were mainly distributed in lysosomes and the Golgi apparatus, with some in the endoplasmic reticulum (ER) and very few in the mitochondrion. At 12 h, the Chol-PEG-FITC molecules mostly aggregated in the Golgi apparatus and ER close to the nucleus. Finally, we demonstrated that Chol-PEG-FITC was toxic to mammalian cells only at concentrations above 50 µM. In summary, Chol-PEG-FITC can be a promising plasma membrane imaging reagent to avoid the fast cellular internalization and quick membrane detachment problems faced by commercial membrane dyes. We believe that the investigation of the dynamic subcellular fate of Chol-PEG-FITC can provide important knowledge to facilitate the use of cholesterol-PEG conjugates in fields such as cell surface engineering and drug delivery.


Assuntos
Membrana Celular/metabolismo , Colesterol/metabolismo , Fluoresceína-5-Isotiocianato/metabolismo , Corantes Fluorescentes/metabolismo , Polietilenoglicóis/metabolismo , Colesterol/análogos & derivados , Colesterol/química , Colesterol/toxicidade , Endocitose/efeitos dos fármacos , Citometria de Fluxo , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/química , Fluoresceína-5-Isotiocianato/toxicidade , Corantes Fluorescentes/química , Corantes Fluorescentes/toxicidade , Humanos , Células MCF-7 , Microdomínios da Membrana/metabolismo , Micelas , Microscopia Confocal , Tamanho da Partícula , Polietilenoglicóis/química , Polietilenoglicóis/toxicidade
20.
Lipids Health Dis ; 15: 110, 2016 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-27341816

RESUMO

BACKGROUND: Our previous reports demonstrated that abdominal paracentesis drainage (APD) exerts a beneficial effect on severe acute pancreatitis (SAP) patients. However, the underlying mechanisms for this effectiveness are not well understood. METHODS: A retrospective cohort of 132 consecutive non-hypertriglyceridemia (HTG)-induced SAP patients with triglyceride (TG) elevation and pancreatitis-associated ascitic fluid (PAAF) was recruited from May 2010 to May 2015 and included in this study. The patients were divided into two groups: the APD group (n = 68) and the non-APD group (n = 64). The monitored parameters mainly included mortality, hospital stay, the incidence of further intervention, levels of serum lipid metabolites and inflammatory factors, parameters related to organ failure and infections, and severity scores. RESULTS: The demographic data and severity scores were comparable between the two groups. Compared with the non-APD group, the primary outcomes (including mortality, hospital stay and the incidence of percutaneous catheter drainage) in the APD group were improved. The serum levels of lipid metabolites were significantly lower in the APD group after 2 weeks of treatment than in the non-APD group. Logistic regression analysis indicated that the decreased extent of free fatty acid (FFA)(odds ratio, 1.435; P = 0.015) was a predictor of clinical improvement after 2 weeks of treatment. CONCLUSION: Treatment with APD benefits non-HTG-induced SAP patients with serum TG elevation by decreasing serum levels of FFA.


Assuntos
Ácidos Graxos não Esterificados/sangue , Pancreatite/sangue , Pancreatite/cirurgia , Paracentese , Triglicerídeos/sangue , Abdome/cirurgia , Doença Aguda , Adulto , Líquido Ascítico/química , Drenagem , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Modelos Logísticos , Pessoa de Meia-Idade , Razão de Chances , Pancreatite/mortalidade , Pancreatite/patologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Análise de Sobrevida , Resultado do Tratamento
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