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1.
Expert Opin Drug Saf ; : 1-6, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38666296

RESUMO

BACKGROUND: Recently, there have been some reports of seizures related with COVID-19 vaccinations. However, no studies have systematically investigated the relationship between seizures and various COVID-19 vaccines. RESEARCH DESIGN AND METHODS: This research aimed to analyze the characteristics and risk signals of new-onset seizures in children caused by various COVID-19 vaccines based on the data of the Vaccine Adverse Event Reporting System (VAERS). To identify potential risk signals, a disproportionality analysis was conducted. The reporting odds ratio (ROR) and the Proportional Reporting Ratio (PRR) were used to detect signals. RESULTS: A total of 695 children with new-onset seizures events associated with COVID-19 vaccinations were retrieved from the VAERS database. Compared with influenza vaccinations, the percentage and rate of COVID-19 vaccinations related seizures was all reduced. The median onset time of seizures was 1 day after COVID-19 vaccines. No signal was detected for an association between the COVID-19 vaccines and new-onset seizures, neither when compared with influenza vaccines nor with non-COVID-19 vaccines. CONCLUSION: No statistically significant risk signal of COVID-19 vaccine-related seizures was found in this study. However, it is still necessary to monitor the possibility of new-onset seizures when children are immunized with COVID-19 vaccines.

3.
J Cutan Med Surg ; 27(5): 504-508, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37533146

RESUMO

Platelet-rich plasma (PRP) contains a variety of growth factors and has been widely used in maxillofacial surgery, orthopedics, plastic surgery, ophthalmology, and other fields. In recent years, with the increasing morbidity of androgenetic alopecia (AGA), the use of PRP has also increased. The objective of this article was to evaluate the efficacy and safety of PRP for AGA. We searched PubMed, Embase, Web of Science, and Cochrane Library, covering the databases from their earliest records until March 2022. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) to explore the effects of PRP for hair density, hair count, and hair diameter in AGA. Nine trials involving 238 patients were included. The meta-analysis showed that PRP for AGA increased hair density at 3 and 6 months with statistically significant differences compared with the placebo (P < .05). PRP also increased hair count and hair diameter compared with the baseline, but there was no significant difference compared with the placebo (P > .05). Two of the 7 studies reported adverse reactions. No serious adverse reactions were found. In conclusion, PRP is an effective and safe treatment for increasing the hair density in AGA. Trial registration: The systematic review was registered with PROSPERO (CRD42022362432).


Assuntos
Alopecia , Plasma Rico em Plaquetas , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Alopecia/terapia , Cabelo , Resultado do Tratamento
4.
Comput Biol Med ; 163: 107164, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37329616

RESUMO

Uterine corpus endometrial carcinoma (UCEC) has a strong ability of invasion and metastasis, high recurrence rate, and poor survival. Glycosyltransferases are one of the most important enzymes that coordinate the glycosylation process, and abnormal modification of proteins by glycosyltransferases is closely related to the occurrence and development of cancer. However, there were fewer reports on glycosyltransferase related biomarkers in UCEC. In this paper, based on the UCEC transcriptome data published on The Cancer Genome Atlas (TCGA), we predicted the relationship between the expression of glycosyltransferase-related genes (GTs) and the diagnosis and prognosis of UCEC using bioinformatics methods. And validation of model genes by clinical samples. We used 4 methods: generalized linear model (GLM), random forest (RF), support vector machine (SVM) and extreme gradient boosting (XGB) to screen biomarkers with diagnostic significance, and the binary logistic regression was used to establish a diagnostic model for the 2-GTs (AUC = 0.979). And the diagnostic model was validated using a GEO external database (AUC = 0.978). Moreover, a prognostic model for the 6-GTs was developed using univariate, Lasso, and multivariate Cox regression analyses, and the model was made more stable by internal validation using the bootstrap. In addition, risk score is closely related to immune microenvironment (TME), immune infiltration, mutation, immunotherapy and chemotherapy. Overall, this study provides novel biomarkers for the diagnosis and prognosis of UCEC, and the models established by these biomarkers can also provide a good reference for individualized and precision medicine in UCEC.


Assuntos
Neoplasias do Endométrio , Glicosiltransferases , Feminino , Humanos , Prognóstico , Glicosiltransferases/genética , Biologia Computacional , Bases de Dados Factuais , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/genética , Biomarcadores Tumorais/genética , Microambiente Tumoral
5.
Front Pharmacol ; 14: 928821, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37089950

RESUMO

Cholesterol and its metabolites have important biological functions. Cholesterol is able to maintain the physical properties of cell membrane, play an important role in cellular signaling, and cellular cholesterol levels reflect the dynamic balance between biosynthesis, uptake, efflux and esterification. Cholesterol metabolism participates in bile acid production and steroid hormone biosynthesis. Increasing evidence suggests a strict link between cholesterol homeostasis and tumors. Cholesterol metabolism in tumor cells is reprogrammed to differ significantly from normal cells, and disturbances of cholesterol balance also induce tumorigenesis and progression. Preclinical and clinical studies have shown that controlling cholesterol metabolism suppresses tumor growth, suggesting that targeting cholesterol metabolism may provide new possibilities for tumor therapy. In this review, we summarized the metabolic pathways of cholesterol in normal and tumor cells and reviewed the pre-clinical and clinical progression of novel tumor therapeutic strategy with the drugs targeting different stages of cholesterol metabolism from bench to bedside.

6.
Cancers (Basel) ; 14(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36291937

RESUMO

Necroptosis is a type of programmed necrosis that is different from apoptosis and necrosis. Lung cancer has the highest incidence and mortality worldwide, and lung adenocarcinoma is the most common subtype of lung cancer. However, the role of necroptosis in the occurrence and development of LUAD remains largely unexplored. In this paper, four NRGs and nine NRGs determined by big data analysis were used to effectively predict the risk of early LUAD (AUC = 0.994) and evaluate the prognostic effect on LUAD patients (AUC = 0.826). Meanwhile, ESTIMATE, single-sample gene set enrichment analysis (ssGSEA), genomic variation analysis (GSVA), gene set enrichment analysis (GSEA), and immune checkpoint analysis were used to explore the enrichment characteristics and immune research related to the prognostic model. In deep data mining, we were surprised to find that prognostic models also regulate the immune microenvironment, cell cycle, and DNA damage repair mechanisms. Thus, we demonstrated a significant correlation between model evaluation results, ICI treatment, and chemotherapeutic drug sensitivity. The low-risk population has a stronger tumor immune response, and the potential for ICI treatment is greater. People at high risk respond less to immunotherapy but respond well to chemotherapy drugs. In addition, PANX1, a core gene with important value in immune regulation, prognosis assessment, and early diagnosis, has been identified for the first time, which provides a new target for the immunotherapy of LUAD as well as a new theoretical basis for the basic research, clinical diagnosis, and individualized treatment of LUAD.

7.
Cancers (Basel) ; 14(16)2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36010886

RESUMO

Necroptosis is a kind of programmed necrosis, which is different from apoptosis and pyroptosis. Its molecular mechanism has been described in inflammatory diseases. Gastric cancer (GC) is one of the most common malignancies worldwide with the third highest mortality. However, the role of necroptosis in the occurrence and progression of GC remains largely unexplored. Therefore, we investigated necroptosis-related genes (NRGs) by analyzing public transcriptomic data from GC samples. Our results indicate that 83 of 740 NRGs are dysregulated in GC tissues. Next, we identified necroptosis-associated early diagnosis and prognostic gene signatures for GC using machine learning. 2-NRGs (CCT6A and FAP) and 4-NRGs (ZFP36, TP53I3, FAP, and CCT6A), respectively, can effectively assess the risk of early GC (AUC = 0.943) and the prognosis of GC patients (AUC = 0.866). Through in-depth analysis, we were pleasantly surprised to find that there was a significant correlation between the 4-NRGs and GC immunotherapy effect and immune checkpoint inhibitors (ICIs), which could be used for the evaluation of immunosuppressants. Finally, we identified the core gene FAP, and established the relationship between FAP and ICIs in GC. These findings could provide a new target for immunotherapy for GC and a more effective treatment scheme for GC patients.

8.
Can J Physiol Pharmacol ; 99(7): 729-736, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33175603

RESUMO

Most sudden cardiac death in chronic heart failure (CHF) is caused by malignant ventricular arrhythmia (VA); however, the molecular mechanism remains unclear. This study aims to explore the effect of exchange proteins directly activated by cAMP (Epac) on VA in CHF and the potential molecular mechanism. Transaortic constriction was performed to prepare CHF guinea pigs. Epac activation model was obtained with 8-pCPT administration. Programmed electrical stimulation (PES) was performed to detect effective refractory period (ERP) or induce VA. Isolated adult cardiomyocytes were treated with 8-pCPT and (or) the Epac inhibitor. Cellular electrophysiology was examined by whole-cell patch clamp. With Epac activation, corrected QT duration was lengthened by 12.6%. The 8-pCPT increased action potential duration (APD) (APD50: 236.9 ± 18.07 ms vs. 328.8 ± 11.27 ms, p < 0.05; APD90: 264.6 ± 18.22 ms vs. 388.6 ± 6.47 ms, p < 0.05) and decreased rapid delayed rectifier potassium (IKr) current (tail current density: 1.1 ± 0.08 pA/pF vs. 0.7 ± 0.03 pA/pF, p < 0.05). PES induced more malignant arrhythmias in the 8-pCPT group than in the control group (3/4 vs. 0/8, p < 0.05). The selective Epac1 inhibitor CE3F4 rescued the drop in IKr after 8-pCPT stimulation (tail current density: 0.5 ± 0.02 pA/pF vs. 0.6 ± 0.03 pA/pF, p < 0.05). In conclusion, Epac1 regulates IKr, APD, and ERP in guinea pigs, which could contribute to the proarrhythmic effect of Epac1 in CHF.


Assuntos
Insuficiência Cardíaca , Potenciais de Ação , Animais , Arritmias Cardíacas , Cobaias , Miócitos Cardíacos
9.
Cell Mol Biol (Noisy-le-grand) ; 65(7): 132-137, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31880531

RESUMO

A decrease in the rapid component of delayed rectifier potassium current (IKr) during chronic heart failure (CHF) prolongs action potential (AP), and plays a key role in the pathogenesis of ventricular arrhythmias. ß-Arrestin2 has been shown to restore the inotropic reserve of ß-adrenergic regulation, but little or nothing is known about its effect on intrinsic channel. This study investigated the role of ß-arrestin2 in the regulation of cardiac hERG/IKr potassium channel and AP during chronic adrenergic stimulation. Single left ventricular myocytes were isolated from guinea pig heart, and were transfected with adenovirus encoding ß-arrestin2, or ß-arrestin2 siRNA or an empty adenovirus. Cell cultures containing 10 nM isoproterenol, 1 nM phenylephrine or vehicle alone (control medium) were electro-physiologically examined after 48 h of incubation. Action potential duration at 50 and 90 % of repolarization (APD50 and APD90) were measured using whole-cell patch-clamp recording. Sustained adrenergic stimulation significantly reduced the density of the IKr current (p < 0.001). ß-Arrestin2 expression in cell cultures treated with isoproterenol or phenylephrine was significantly downregulated after adrenergic stimulation (p < 0.001). Overexpression of ß-arrestin2 significantly attenuated isoproterenol or phenylephrine-induced reduction in IKr current. It also prevented the phenylephrine-induced prolongation of AP (p < 0.05 for APD50 and p < 0.001 for APD90), but did not significantly affect AP profile after exposure of the cardiomyocytes to isoproterenol (p > 0.05). Therefore, Increased levels of ß-Arrestin2 weaken dysregulation of IKr current and prevent excessive AP prolongation, making it an effective anti-arrhythmic strategy.


Assuntos
Potenciais de Ação/fisiologia , Arritmias Cardíacas/metabolismo , Miócitos Cardíacos/metabolismo , Canais de Potássio/metabolismo , beta-Arrestina 2/metabolismo , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/genética , Animais , Células Cultivadas , Cobaias , Isoproterenol/farmacologia , Masculino , Técnicas de Patch-Clamp , Fenilefrina/farmacologia , beta-Arrestina 2/genética
10.
Small ; 11(8): 913-8, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25315252

RESUMO

A novel, apertureless, cantilever-free pen array can be used for dual scanning photochemical and molecular printing. Serial writing with light is enabled by combining self-focusing pyramidal pens with an opaque backing between pens. The elastomeric pens also afford force-tuned illumination and simultaneous delivery of materials and optical energy. These attributes make the technique a promising candidate for maskless high-resolution photopatterning and combinatorial chemistry.


Assuntos
Nanotecnologia/métodos , Polímeros/química , Impressão/métodos , Técnicas de Química Combinatória , Desenho de Equipamento , Tinta , Luz , Nanopartículas Metálicas/química , Microscopia de Fluorescência , Nanotecnologia/instrumentação , Óptica e Fotônica , Tamanho da Partícula , Impressão/instrumentação , Propriedades de Superfície , Raios Ultravioleta
11.
Nano Lett ; 14(4): 2157-61, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24661194

RESUMO

We report the large-area assembly of anisotropic gold nanoparticles into lithographically defined templates with control over their angular position using a capillary force-based approach. We elucidate the role of the geometry of the templates in the assembly of anisotropic nanoparticles consisting of different shapes and sizes. These insights allow us to design templates that immobilize individual triangular nanoprisms and concave nanocubes in a shape-selective manner and filter undesired impurity particles from a mixture of triangular prisms and other polyhedra. Furthermore, by studying the assembly of two particles in the same template, we elucidate the importance of interparticle forces in this method. These advances allow for the construction of face-to-face and edge-to-edge nanocube dimers as well as triangular nanoprism bowtie antennas. As an example of the fundamental studies enabled by this assembly method, we investigate the surface-enhanced Raman scattering (SERS) of face-to-face concave cube dimers both experimentally and computationally and reveal a strong polarization dependence of the local field enhancement.

12.
ACS Nano ; 8(2): 1511-6, 2014 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-24450422

RESUMO

We report the large-area alignment of multi-segmented nanowires in nanoscale trenches facilitated by capillary forces. Electrochemically synthesized nanowires between 120 and 250 nm in length are aligned and then etched selectively to remove one segment, resulting in arrays of nanowires with precisely controlled gaps varying between 2 and 30 nm. Crucial to this alignment process is the dispersibility of the nanowires in solution which is achieved by chemically modifying them with hexadecyltrimethylammonium bromide. We found that, even without the formation of an ordered crystalline phase at the droplet edges, the nanowires can be aligned in high yield. To illustrate the versatility of this approach as a nanofabrication technique, the aligned nanowires were used for the fabrication of arrays of gapped graphene nanoribbons and SERS substrates.

13.
Nat Mater ; 12(8): 741-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23685863

RESUMO

Nanoparticles can be combined with nucleic acids to programme the formation of three-dimensional colloidal crystals where the particles' size, shape, composition and position can be independently controlled. However, the diversity of the types of material that can be used is limited by the lack of a general method for preparing the basic DNA-functionalized building blocks needed to bond nanoparticles of different chemical compositions into lattices in a controllable manner. Here we show that by coating nanoparticles protected with aliphatic ligands with an azide-bearing amphiphilic polymer, followed by the coupling of DNA to the polymer using strain-promoted azide-alkyne cycloaddition (also known as copper-free azide-alkyne click chemistry), nanoparticles bearing a high-density shell of nucleic acids can be created regardless of nanoparticle composition. This method provides a route to a virtually endless class of programmable atom equivalents for DNA-based colloidal crystallization.


Assuntos
DNA/química , Nanopartículas/química , Azidas/química , Nanopartículas de Magnetita/química , Modelos Moleculares , Conformação Molecular , Tamanho da Partícula , Pontos Quânticos
14.
Nano Lett ; 13(4): 1616-21, 2013 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-23484520

RESUMO

We show that Rhodamine 6G (R6G), patterned by dip-pen nanolithography on graphene, can be used to locally n-dope it in a controlled fashion. In addition, we study the transport and assembly properties of R6G on graphene and show that in general the π-π stacking between the aromatic components of R6G and the underlying graphene drives the assembly of these molecules onto the underlying substrate. However, two distinct transport and assembly behaviors, dependent upon the presence or absence of R6G dimers, have been identified. In particular, at high concentrations of R6G on the tip, dimers are transferred to the substrate and form contiguous and stable lines, while at low concentrations, the R6G is transferred as monomers and forms patchy, unstable, and relatively ill-defined features. Finally, Kelvin probe force microscopy experiments show that the local electrostatic potential of the graphene changes as function of modification with R6G; this behavior is consistent with local molecular doping, highlighting a path for controlling the electronic properties of graphene with nanoscale resolution.


Assuntos
Grafite/química , Rodaminas/química , Microscopia de Força Atômica , Análise Espectral Raman , Eletricidade Estática , Propriedades de Superfície
15.
Small ; 9(18): 3058-62, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-23427089

RESUMO

Traditionally, scanning probe lithography tools are limited in resolution by the radius of curvature of the tip used. Herein, an approach is described for patterning the ridge of piled-up polymer that naturally occurs when a scanning probe is pressed against a soft surface. The use of this phenomenon to transfer patterns to hard materials with 20 nm resolution is demonstrated.


Assuntos
Nanoestruturas/química , Nanotecnologia/métodos , Microscopia de Força Atômica
16.
Small ; 9(3): 382-6, 2013 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-23065912

RESUMO

Well-aligned graphene oxide (GO) scrolls are prepared through the controlled folding/scrolling of single-layer GO sheets using molecular combing on hydrophobic substrates, such as aged gold substrate, polydimethylsiloxane film, poly(L-lactic acid) film, and octadecyltrimethoxysilane-modified silicon dioxide. As a proof of concept, the gas sensor fabricated with a single reduced GO scroll is used to detect NO(2) gas with a concentration as low as 0.4 ppm.


Assuntos
Gases/análise , Grafite/química , Óxidos/química , Gases/química , Interações Hidrofóbicas e Hidrofílicas , Dióxido de Nitrogênio/análise , Dióxido de Nitrogênio/química
17.
Proc Natl Acad Sci U S A ; 109(45): 18312-7, 2012 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-23086161

RESUMO

Scanning probe instruments have expanded beyond their traditional role as imaging or "reading" tools and are now routinely used for "writing." Although a variety of scanning probe lithography techniques are available, each one imposes different requirements on the types of probes that must be used. Additionally, throughput is a major concern for serial writing techniques, so for a scanning probe lithography technique to become widely applied, there needs to be a reasonable path toward a scalable architecture. Here, we use a multilayer graphene coating method to create multifunctional massively parallel probe arrays that have wear-resistant tips of uncompromised sharpness and high electrical and thermal conductivities. The optical transparency and mechanical flexibility of graphene allow this procedure to be used for coating exceptionally large, cantilever-free arrays that can pattern with electrochemical desorption and thermal, in addition to conventional, dip-pen nanolithography.

18.
Nano Lett ; 12(9): 4734-7, 2012 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-22889421

RESUMO

We report a simple and highly efficient method for creating graphene nanostructures with gaps that can be controlled on the sub-10 nm length scale by utilizing etch masks comprised of electrochemically synthesized multisegmented metal nanowires. This method involves depositing striped nanowires with Au and Ni segments on a graphene-coated substrate, chemically etching the Ni segments, and using a reactive ion etch to remove the graphene not protected by the remaining Au segments. Graphene nanoribbons with gaps as small as 6 nm are fabricated and characterized with atomic force microscopy, scanning electron microscopy, and Raman spectroscopy. The high level of control afforded by electrochemical synthesis of the nanowires allows us to specify the dimensions of the nanoribbon, as well as the number, location, and size of nanogaps within the nanoribbon. In addition, the generality of this technique is demonstrated by creating silicon nanostructures with nanogaps.


Assuntos
Cristalização/métodos , Grafite/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Impressão Molecular/métodos , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
19.
Nanoscale Res Lett ; 7: 161, 2012 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-22373422

RESUMO

The comparison between two kinds of single-layer reduced graphene oxide (rGO) sheets, obtained by reduction of graphene oxide (GO) with the electrochemical method and hydrazine vapor reduction, referred to as E-rGO and C-rGO, respectively, is systematically studied. Although there is no morphology difference between the E-rGO and C-rGO films adsorbed on solid substrates observed by AFM, the reduction process to obtain the E-rGO and C-rGO films is quite different. In the hydrazine vapor reduction, the nitrogen element is incorporated into the obtained C-rGO film, while no additional element is introduced to the E-rGO film during the electrochemical reduction. Moreover, Raman spectra show that the electrochemical method is more effective than the hydrazine vapor reduction method to reduce the GO films. In addition, E-rGO shows better electrocatalysis towards dopamine than does C-rGO. This study is helpful for researchers to understand these two different reduction methods and choose a suitable one to reduce GO based on their experimental requirements.

20.
ACS Appl Mater Interfaces ; 4(2): 687-93, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22276668

RESUMO

Poly(L-lactic acid) (PLLA) is widely used in drug delivery and medical implants. Surface modification of PLLA with functional groups to immobilize gelatin or other extracellular matrix proteins is commonly used to improve its cellular affinity. In this work, we use the oxygen plasma to treat PLLA film followed by modification with organosilanes with different functional groups, such as amine, epoxy, and aldehyde groups. Gelatin is then immobilized on the modified PLLA film, which is confirmed by water contact angle measurement, atomic force microscopy (AFM), and laser scanning confocal microscopy (LSCM). Among the used organosilanes, aminosilane is the best one for modification of PLLA used for immobilization of gelatin with the highest efficiency. Moreover, the cellular affinity of gelatin-immobilized PLLA is studied through the evaluation of cell proliferation and focal adhesion using the human umbilical vein endothelial cells (HUVECs). Our experimental results show that the gelatin immobilized on aminosilane- and aldehyde-silane-modified PLLA improves the cellular affinity of HUVECs, whereas that immobilized on epoxy-silane-modified PLLA does not show significant improvement on the cell proliferation.

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