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1.
Opt Express ; 27(20): 28551-28563, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684605

RESUMO

We report surface plasmon enhanced random lasing action and weak localization owing to charge accumulation on the grain boundaries and its spectral transformation in powdered Nd3+ doped lithium niobate (Nd: LN) specimens. Accumulative charge density resulting from screening of electric field of spontaneous polarization was estimated, proving that surface plasmons (SPs) can be excited on the grain boundaries of powdered Nd: LN. The SP based scattering is believed responsible for random lasing to occur, which was further confirmed by the estimation of the scattering mean free path and the scattering cross section and intriguing three step-like backscattering reduction observed in the process of monitoring the variation of reflection spectrum with increasing pumping power. Under a certain pumping power, the powdered Nd: LN specimen was melted locally and this resulted in great changes in random lasing wavelengths. To delve into the reason behind these changes, photoluminescence spectra of the specimens were measured before and after melting. By taking a close look at their dynamics and slopes, it was found that spectral transformation of random lasing occurred owing to the change of lattice structure in powdered Nd: LN.

2.
Technol Cancer Res Treat ; 18: 1533033819883633, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31684829

RESUMO

OBJECTIVE: To investigate the effect of long noncoding RNA GM16343 on interleukin 36ß promotion of CD8+T cells in tumor microenvironment regulation. METHODS: The differentially expressed long noncoding RNA in interleukin 36ß-stimulated mouse CD8+T cells was screened by gene chip technology, and the significant differentially expressed long noncoding RNAs were verified by real-time polymerase chain reaction. The lentiviral vector that overexpresses or knockdown GM16343 was constructed, transfected into CD8+T cells, and stimulated with interleukin 36ß, and the amount of interferon γ secreted was detected by enzyme-linked immunosorbent assay. A mouse subcutaneous xenograft model that stably express interleukin 36ß was established, and the tumor size and mouse survival time were observed by stimulation with CD8+T cells overexpression or knockdown of GM16343. RESULTS: A total of 12 long noncoding RNAs with significant differences were screened by gene chip analysis. Real-time polymerase chain reaction showed that the difference in GM16343 was larger, and the difference between the groups was observed to be the most significant. Compared to control group, CD8+T cells overexpressing GM16343 increased the secretion of interferon γ, and the tumor diameter of the mice after stimulation showed significant reduction, and the survival time showed significant prolongation. Compared to control group, the CD8+T cells after GM16343 were knocked down. The interferon γ secretion was decreased, and no significant change in tumor diameter and survival time was observed. CONCLUSION: Interleukin 36ß may enhance antitumor immune response of CD8+T cells by regulating GM16343.

3.
Int J Pharm ; : 118864, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31765782

RESUMO

Natural phenolic drugs have good safety and various biological activities. However, poor bioavailability and inadequate bioactivity severely limit their application. A novel composite alkali polysaccharide nanovesicle was formed with supramolecule- and nano- technologies to efficiently deliver natural phenolic antitumor drugs. Alkali polysaccharide nanovesicles (ASDLM) containing supramolecular diferuloylmethane (DLM) had the additional effects of alkali polysaccharide nanovesicles and supramolecules of drug and high-molecular-weight polymers. DLM was isolated from the external environment when double loaded by cyclodextrin and nanovesicles; The nanosize, negative/positive charges and supramolecular structure were beneficial attributes that helped to increase the bioavailability and antitumor activity; supramolecular DLM-loaded nanovesicles made of natural biodegradable excipients showed good safety. Compared to free DLM, ASDLM exhibited superior physicochemical characteristics, favorable changes in the in vitro/in vivo kinetic performance, a possible in vitro-in vivo correlation, enhanced in situ gastrointestinal absorption, increased bioavailability, and an elevated anti-lung cancer efficiency. Composite alkali polysaccharide nanovesicles conjugated with supramolecular-/nano- technology may provide a valuable platform for the oral delivery of botanical drugs to meet clinical requirements.

4.
Opt Lett ; 44(21): 5370-5373, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31675009

RESUMO

An all-fiber orbital angular momentum (OAM) generator enabling direct turning of the fundamental mode (${{\rm HE}_{11}}$HE11) to the second OAM modes (${ l} = {\pm 2}$l=±2) with an efficiency of $\sim90\% $∼90% has been proposed and experimentally demonstrated, which is realized based on utilization of a second-order helical fiber grating written in a few-mode fiber. This is the first time, to the best of our knowledge, that an all-fiber second-order OAM has been achieved with using only one component, i.e., the helical long-period fiber grating. The proposed method opens a new way to efficiently generate an all-fiber higher-order OAM using a conventional multimode fiber.

5.
J Orthop Surg (Hong Kong) ; 27(3): 2309499019879540, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31645192

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the feasibility of posterior occipital condyle screw (OCS) placement analysis of the safe trajectory area for screw insertion. METHODS: Computed tomographic angiography scans of patients (46 males and 27 females) with normal occipitocervical structures were obtained consecutively. Vertebral artery (VA)-occiput distance <4.0 mm was defined as "unfeasible" for OCS fixation, and occipital-atlas angulation was measured to assess the feasibility of screw placement. Next, the placement of 3.5 mm diameter OCS was simulated, the probability of breach of structures surrounding occipital condyles was calculated, and placement parameters were analyzed. RESULTS: OCS placement was feasible in 91.1% (133/146) of occipital condyles, and the feasible probability also presented a significant sex-related difference: The probability was higher for males than for females (95.7% vs. 83.3%, p < 0.05). The incidence of anatomical structures injured under screw placement limitation was 18.8% (VA), 81.2% (hypoglossal canal), 59.4% (occipital-atlas joint), and 40.6% (occiput bone surface). There were no significant differences between the left and right condyles in relation to the measured parameters (p > 0.05). The screw range of motion was significantly smaller in females than in males (p < 0.05). The feasibility of OCS placement and OCS range of motion were significantly greater in the kyphosis group (>5°) than in the other two groups (p < 0.05). CONCLUSION: OCS placement is a feasible technique for occipital-cervical fusion. The male group and occipitocervical region kyphosis group had a wider available space for OCS placement. Tangent angulation may be useful for the accurate and safe placement of an OCS.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31566116

RESUMO

DNA groove binders have been poorly studied as compared to the intercalators. A novel Ru(II) complex of [Ru(aeip)2(Haip)](PF6)2 {Haip = 2-(9-anthryl)-1H-imidazo[4,5-f][1,10]phenanthroline and aeip = 2-(anthracen-9-yl)-1-ethyl-imidazo[4,5-f][1, 10]phenanthroline} is synthesized and characterized by elemental analysis, 1H NMR spectroscopy and mass spectrometry. The complex is evidenced to be a calf-thymus DNA groove binder with a large intrinsic binding constant of 106 M-1 order of magnitude as supported by UV-visible absorption spectral titrations, salt effects, DNA competitive binding with ethidium bromide, DNA melting experiment, DNA viscosity measurements and density functional theory calculations. The acid-base properties of the complex studied by UV-Vis spectrophotometric titrations are reported as well.

7.
Stat Med ; 38(28): 5332-5349, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31637752

RESUMO

New treatments that are noninferior or equivalent to-but not necessarily superior to-the reference treatment may still be beneficial to patients because they have fewer side effects, are more convenient, take less time, or cost less. The noninferiority test is widely used in medical research to provide guidance in such situation. In addition, categorical variables are frequently encountered in medical research, such as in studies involving patient-reported outcomes. In this paper, we develop a noninferiority testing procedure for correlated ordinal categorical variables based on a paired design with a latent normal distribution approach. Misclassification is frequently encountered in the collection of ordinal categorical data; therefore, we further extend the procedure to account for misclassification using information in the partially validated data. Simulation studies are conducted to investigate the accuracy of the estimates, the type I error rates, and the power of the proposed procedure. Finally, we analyze one substantive example to demonstrate the utility of the proposed approach.

9.
Methods Enzymol ; 627: 1-21, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31630737

RESUMO

Aliphatic polyesters are thermoplastic and biodegradable polymers with promising potentials to substitute synthetic polymers derived from petrochemicals. In particular, polylactides (PLAs) and other polylactones can be renewable and biocompatible. A more benign approach for polyester synthesis is the enzymatic polycondensation or ring-opening polymerization (ROP) reactions, whose outcomes largely depend on the reaction conditions including solvents, water content and temperature. This chapter illustrates several examples of enzymatic polymerization to polyesters using various solvents (i.e., organic solvents, supercritical fluids, ionic liquids, and aqueous biphasic systems). Hydrophobic solvents containing little water tend to promote the enzymatic polymerization and lead to high molecular masses of polyesters. Since some enzymatic polymerization reactions are performed at high temperatures (such as ring-opening polymerization of lactide at >100°C), these processes demand solvents with high boiling points (such as many ionic liquids). Supercritical fluids (such as supercritical CO2) can be "green" solvents, but their compatibility with enzymes and their practicability of scaling up remain as challenges. On the other hand, ionic liquids can be tailored to be compatible with enzymes and to have high thermal stability although the studies of their uses in enzymatic polycondensation and ROP reactions are still at an early stage.

10.
Br J Nutr ; 122(10): 1081-1090, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31637977

RESUMO

The present study compared the protective effect of sodium selenite (SS) and selenomethionine (SeMet) on heat stress (HS)-invoked porcine IPEC-J2 cellular damage and integrate potential roles of corresponding selenoprotein. Cells were cultured at 37°C until 80 % confluence and then subjected to four different conditions for 24 h: at 37°C (control), 41·5°C (HS), 41·5°C supplied with 0·42 µmol Se/L SS (SS), or SeMet (SeMet). HS significantly decreased cell viability, up-regulated mRNA and protein levels of heat shock protein 70 (HSP70) and down-regulated mRNA and protein levels of tight junction-related proteins (claudin-1 (CLDN-1) and zonula occludens-1 (ZO-1)). HS-induced cell injury was associated with the up-regulation (P < 0·05) of six inflammation-related genes and fourteen selenoprotein encoding genes and down-regulation (P < 0·05) of two inflammation-related genes and five selenoprotein encoding genes. Compared with the HS group, SS and SeMet supplementation resulted in an increase (P < 0·05) in cell viability, decreased (P < 0·05) mRNA expression of HSP70 and six inflammation-related genes and rescue (P < 0·05) of mRNA and protein levels of CLDN-1 and ZO-1. SS and SeMet supplementation changes the expressions of nineteen selenoprotein encoding genes in cells affected by HS. Both Se supplementation significantly recovered the protein level of glutathione peroxidase-1 and increased selenoprotein P in the IPEC-J2 cells under HS, respectively. In summary, Se supplementation alleviated the negative impact of HS on IPEC-J2 cells, and their cellular protective effect was associated with regulation expression of selenoproteins, and SeMet exhibited a better protective effect.

11.
Medicine (Baltimore) ; 98(42): e17632, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31626148

RESUMO

This study retrospectively analyzed the feasible effectiveness of ultrasound-guided acupotomy (USGAP) for the treatment of frozen shoulder (FS). A total of 36 patients with FS were analyzed in this retrospective study. All 36 patients received extracorporeal shock-wave therapy (ESWT). In addition, 18 of them also underwent USGAP intervention and were assigned to a treatment group, while the other 18 patients did not receive such intervention and were assigned to a control group. The primary efficacy endpoint was pain intensity, as measured by the Numeric Rating Scale (NRS). The secondary efficacy endpoint was assessed by the score of shoulder pain and disability index (SPADI). Furthermore, the adverse events were also documented during the treatment period. All efficacy endpoints were measured after the treatment. After treatment, patients who received USGAP exerted better efficacy endpoints in pain relief, as measured by NRS scale (P < .01), and shoulder disorders, as evaluated by SPADI (P < .01), than subjects who did not receive USGAP. Additionally, no adverse events occurred in either group. The results of this study indicated that USGAP may be used for the treatment of FS effectively. More studies are still needed to warrant the present results.


Assuntos
Terapia por Acupuntura/métodos , Bursite/terapia , Tratamento por Ondas de Choque Extracorpóreas/métodos , Terapia Assistida por Computador/métodos , Ultrassonografia/métodos , Bursite/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Retrospectivos , Resultado do Tratamento
12.
Inorg Chem ; 58(20): 14244-14259, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31595752

RESUMO

Near-IR-emitting and/or efficiently photodynamic water-soluble Ru(II) complexes that hold great application potentials as photodynamic therapy and/or photodetection agents for cancers have been poorly explored. In this paper, the solvatochromism, calf thymus DNA binding, and singlet oxygen generation properties of a known ruthenium(II) complex of visible-emitting [Ru(bpy)2(dtdpq)](ClO4)2 (Ru1) and a new homoleptic complex of near-IR-emitting [Ru(dtdpq)3](ClO4)2 (Ru2) (bpy = 2,2'-bipyridine, dtdpq = 2,3-bis(thiophen-2-yl)pyrazino[2,3-f][1,10]phenanothroline) in water are reported. Moreover, DNA photocleavage, singlet oxygen generation in HeLa cells, cellular uptake/localization, and in vitro photodynamic therapy for cancer cells of water-soluble Ru1 are described in detail. The results show that Ru1 acted as potent photodynamic cancer therapy and mitochondrial imaging agents. Ru2 exhibited very strong solvatochromism from a visible emission maximum at 588 nm in CH2Cl2 to the near-IR region at 700 nm in water and singlet oxygen generation yield in water (23%) and DNA binding properties (intercalative DNA binding constant on the order of 106 M-1) comparable to those of Ru1, which should make Ru2 attractive for the aforementioned applications of Ru1 if the water solubility of Ru2 can be improved enough for the studies above.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , DNA de Neoplasias/efeitos dos fármacos , Luz , Fotoquimioterapia , Rutênio/farmacologia , Tiofenos/farmacologia , Células A549 , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Sítios de Ligação/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Células HeLa , Humanos , Raios Infravermelhos , Células MCF-7 , Estrutura Molecular , Oxigênio/análise , Oxigênio/metabolismo , Rutênio/química , Tiofenos/química
14.
Sci Rep ; 9(1): 13668, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31541120

RESUMO

Sporadic outbreaks caused by coxsackievirus A4 (CV-A4) have been reported worldwide. To further elucidate the detailed genetic characteristics and evolutionary recombination events of CV-A4, virus samples from nationwide hand, foot and mouth disease (HFMD) surveillance, encompassing 27 out of the 31 provinces in China, were investigated. Comprehensive and systematic phylogenetic analyses were performed by using 29 complete genomes, 142 complete CV-A4 VP1 sequences. Four genotypes (A, B, C and D) and five sub-genotypes (C1-C5) were re-identified based on the complete VP1 sequences. C2 is the predominant sub-genotype of CV-A4 associated with HFMD and has evolved into 3 clusters. Cluster 1 is a major cluster that has been persistently and extensively circulating in China since 2006 and has been associated with all severe cases. All the sequences showed high homology with the CV-A4 prototype in the P1 region, while higher identities with CV-A5, CV-14 and CV-16 in the P2 and P3 regions. Recombination analysis revealed that C2 had two specific genetic recombination patterns with other EV-A prototypes in the 5'-UTR and 3D region compared with C5. These recombination patterns might be associated with the increased transmissibility of C2 viruses, which were obtained due to their persistent and extensive circulation in populations.

16.
J Cardiovasc Electrophysiol ; 30(11): 2414-2419, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31502295

RESUMO

BACKGROUND: Ablation index (AI) has been evaluated as guidance quality marker for pulmonary vein isolation, but not for linear ablation of the cavotricuspid isthmus (CTI) for typical right atrial flutter (AFL). We thus studied the feasibility and effectiveness of AI-guided CTI for AFL. METHODS: Procedural and 6-month outcomes of ablation for AFL were retrospectively compared between consecutive patients undergoing either AI-guided ablation of CTI (n = 43; AI target of 500 for anterior 2/3 segments and 400 for posterior 1/3 segments) or contact force (CF)-guided ablation (n = 42) at a single center. Each Visitag dataset from all patients in each group was analyzed. RESULTS: AI guidance vs CF guidance was associated with: higher first-pass conduction block of CTI (93.0% vs 76.2%, P = .03) with similar ablation time; similar acute spontaneous CTI reconnection 2.3% vs 9.5%, P = .343); fewer radiofrequency (RF) applications (10.1 ± 2.8 vs 11.5 ± 3.0, P = .031) needed to achieve CTI directional block; significantly higher mean ablation time, impedance drop, force time integral and AI and similar mean CF and power of each VisiTag point. One inguinal hematoma and one pseudoaneurysm developed in the AI and CF groups, respectively. Recurrent AFL was recorded in two (4.7%) AI-group patients and four (9.5%) CF-group patients (P = .650). CONCLUSION: AI-guided ablation of CTI line for AFL appears feasible and effective with similar ablation time, fewer RF applications, a higher rate of first-pass conduction block, and no additional complications.

17.
FEBS Lett ; 593(19): 2706-2715, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31380564

RESUMO

Angiopoietins (Angs) are a family of vascular growth factors that share multiple cellular functions related to cell survival, proliferation, and migration. Angs play physiological and pathological roles through the Tie tyrosine kinase receptors. The Ang-Tie signaling pathway participates in the developmental and tumor-induced angiogenesis and is also involved in many disease settings, such as vascular diseases, systemic inflammation, and cancers. Since Angs are widely expressed in the kidney, an enormous amount of research focuses on their roles in the kidney. In this review, we describe the biological functions of the Ang-Tie signaling pathway and summarize their roles in kidney development and maturation, acute and chronic kidney diseases, diabetic nephropathy, lupus nephropathy, hemolytic uremic syndrome, end-stage renal diseases, and renal cell carcinoma. Understanding the molecular mechanisms of Ang-Tie signaling may reveal potential therapeutic targets for preventing or alleviating kidney diseases.

18.
Neurochem Res ; 44(9): 2182-2189, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31410708

RESUMO

Tripartite motif 32 (TRIM32) is a member of TRIM family that plays a potential role in neural regeneration. However, the biological function of TRIM32 in cerebral ischemia reperfusion injury has not been investigated. In the present study, we evaluated the expression level of TRIM32 in hippocampal neurons following oxygen-glucose deprivation/reperfusion (OGD/R). The results showed that TRIM32 expression was significantly elevated in hippocampal neurons subjected to OGD/R as compared to the neurons cultured in the normoxia condition. To further evaluate the role of TRIM32, hippocampal neurons were transfected with TRIM32 small interfering RNA (si-TRIM32) to knock down TRIM32. We found that knockdown of TRIM32 improved cell viability of OGD/R-stimulated hippocampal neurons. Generation of reactive oxygen species was decreased, while contents of superoxide dismutase and glutathione peroxidase were increased after si-TRIM32 transfection. Knockdown of TRIM32 suppressed cell apoptosis, as proved by the increased bcl-2 expression along with decreased bax expression and caspase-3 activity. We also found that TRIM32 knockdown enhanced OGD/R-induced activation of Nrf2 signaling pathway in hippocampal neurons. Furthermore, siRNA-Nrf2 was transfected to knock down Nrf2. SiRNA-Nrf2 transfection reversed the protective effects of TRIM32 knockdown on neurons. These data suggested that knockdown of TRIM32 protected hippocampal neurons from OGD/R-induced oxidative injury through activating Nrf2 signaling pathway.

20.
Biol Trace Elem Res ; 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432444

RESUMO

Dietary zinc status was recently approved to exert a powerful influence on liver health, and zinc deficiency results in hepatic injury caused by fat deposition, inflammation, and oxidant stress, but the effect of zinc on hepatic lipid metabolism and liver injury in meat duck has not been well defined. To determine the hepatoprotective effects of graded zinc glycine in meat ducks. A total of 384 1-day-old male meat ducks were subjected to 5 weeks feeding program with three experimental diets: (1) low-zinc diet, (2) adequate-zinc diet, and (3) high-zinc diet. Blood and liver samples were collected for biochemical analysis, gene expression analysis, and histopathological study. Diet with low zinc increased hepatic lipid content and triglyceride concentration. Meat ducks fed low-zinc diet exhibited considerably increased serum alanine aminotransferase (ALT) activity than birds fed other diets among all groups (P < 0.05). Low zinc administration also notably induced hepatocyte apoptosis and stimulated hepatic inflammatory gene expression. Adequate or high zinc supplementation increased hepatic zinc level, reduced hepatic lipid deposition and hepatosomatic indices through suppressing the expression of lipogenic genes including fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) (P < 0.05), and upregulated the mRNA expression of both fatty acid secretion and ß-oxidation, including carnitine palmitoyltransferase 1a (Cpt1a), peroxisome proliferator-activated receptor (PPAR)α, and apolipoprotein B (ApoB) (P < 0.05). Dietary zinc addition also declined hepatic mRNA expression of interleukin (IL)-1ß and IL-6 (P < 0.05). Furthermore, diets with adequate or high zinc significantly decreased serum ALT activity and hepatocyte apoptosis. These data revealed that supplementing adequate- or high-zinc glycine efficiently protects liver injury by attenuating lipid deposition and hepatic inflammation.

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