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1.
Int J Biol Macromol ; 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31476399

RESUMO

The physical mechanics and structural properties of composite films based on chitosan and syringic acid (SA) were studied in this study. The results indicated that the addition of SA made the chitosan-SA films exhibited higher density, water solubility and opacity, but the water vapor permeability and water content were decreased. In addition, Chitosan-SA films had a significant antibacterial effect on test bacteria. The surface and cross-section of chitosan-SA films were more uniform and smoother when combined with 0.25% and 0.5% 0f SA. The FT-IR and XRD spectra of the chitosan-SA film indicated that the interaction between chitosan and SA may be non-covalent, and DSC indicated that the thermal stability of the composite film was reduced. In summary, the modified color, increased bacteriostatic and water-blocking properties, as well as the slight changes in mechanical properties indicated that the addition of SA may contribute to extend the shelf life of the food. Thus, chitosan-SA films incorporating 0.25% and 0.5% of SA can be further explored as active packing materials for food preservation. The composite film was used for the preservation of quail egg coatings, and it was found that 0.25% and 0.5% of the coating film had a good preservation effect.

2.
J Am Heart Assoc ; 8(18): e011948, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31480879

RESUMO

Background Few reports have addressed the mechanism by which microRNA miR-10b-5p regulates post-myocardial infarction (post-MI) cardiomyocyte apoptosis under hypoxic conditions. Methods and Results C57BL/6 mice underwent surgical ligation of the left anterior descending artery to create an MI or ischemia/reperfusion animal model. The expression of miR-10b-5p, PTEN (phosphatase and tensin homolog), and HIF-1α (hypoxia-inducible factor 1α) was detected in infarct border zone tissues at various time points. After precordial injections of the negative control or miR-10b-5p, overexpression lentiviruses were made in the areas surrounding the MI sites at 1 week, and myocardial infarct size, cardiac function, and cardiomyocyte apoptosis were examined. A miR-10b-5p mimic was transfected into primary mouse cardiomyocytes to analyze its effects on cardiomyocyte apoptosis and PTEN expression. Meanwhile, PTEN as a target of miR-10b-5p was verified via luciferase reporter gene assays. Cotransfection of miR-10b-5 and PTEN verified the relationship between miR-10b-5 and PTEN. Under hypoxic stress, the expression of HIF-1α and miR-10b-5p was examined. The results showed that miR-10b-5p expression was markedly reduced in the infarct border zone. Overexpression of miR-10b-5p in the murine model of MI significantly reduced MI size, improved cardiac function, and inhibited apoptosis. Overexpression of miR-10b-5p in vitro antagonized hypoxia-induced cardiomyocyte apoptosis and specifically inhibited the expression of the apoptosis-related gene PTEN, but overexpression of PTEN weakened these effects. We also found that hypoxia-induced accumulation of HIF-1α resulted in decreased expression of miR-10b-5p. Interfering with the activation of the HIF-1α signaling pathway promoted Pri-miR-10b and miR-10b-5p expression and inhibited PTEN expression. Conclusions MicroRNA miR-10b-5p antagonizes hypoxia-induced cardiomyocyte apoptosis, indicating that miR-10b-5p may serve as a potential future clinical target for the treatment of MI.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31367900

RESUMO

Calcific aortic valve disease (CAVD) is characterized by progressive mineralization of the aortic valve. Lipid infiltration and oxidative stress are the driving forces for the initiation and development of this disease. However, it remains unknown whether oxidized high-density lipoprotein (ox-HDL) plays a role in the mineralization of aortic valve interstitial cells (AVICs). Serum ox-HDL levels were determined in 168 severe CAVD patients and 168 age- and gender-matched non-CAVD controls. Results showed that ox-HDL concentrations were significantly increased in CAVD compared with the control group (131.52 ± 30.96 ng/mL vs. 112.58 ± 32.20 ng/mL, P < 0.001) and were correlated with CAVD severity. Multivariable logistic regression revealed that ox-HDL levels were independently associated with CAVD after adjusting for the incidence of coronary artery disease (CAD) (odds ratio 1.019, 95% CI 1.012-1.027, P < 0.001) or atherosclerotic risk factors (odds ratio 1.027, 95% CI 1.017-1.037, P < 0.001). Chronic ox-HDL stimulation of AVICs increased alkaline phosphatase activity (ALP) and calcium deposits in AVICs in vitro. Mechanistic studies further showed that ox-HDL upregulated several osteogenic factors, including BMP-2, Runx2, and Msx2 expressions in AVICs. This is the first study to demonstrate a relationship between increased ox-HDL concentration and CAVD incidence.

4.
Dalton Trans ; 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31432059

RESUMO

Four novel homoleptic triple-decker lanthanide complexes, [Ln2(L)(Cl-salphen)2]·0.5ClCH2CH2Cl (Ln3+ = Gd3+ (1), Ho3+ (2), Tb3+ (3), and Dy3+ (4)), have been designed and synthesized based on a Schiff base ligand N,N'-bis(5-chlorosalicylidene)-o-phenylenediamine (Cl-salphenH2) and the building blocks [(acac)4Ln2(L)]; these complexes were derived from a closed-macrocyclic ligand (H2L) obtained by the [2 + 2] template condensation of 2,6-diformyl-4-methylphenol and 1,3-diaminopropane in the presence of lanthanide acetylacetonates. Single-crystal X-ray analyses show that central Ln3+ ions adopt distorted square antiprism conformations with D4d symmetry. Theoretical analysis and magnetic measurements reveal that Dy complex 4 behaves as a typical SMM with the characteristics of slow magnetic relaxation behavior and intermetallic ferromagnetic interaction.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31430114

RESUMO

Bismuth (Bi), a topological material, where many interesting condensed matter phenomena have been observed, possesses unique physical properties when its thickness is reduced to thin film. Here, we prepared the highly stable, single-crystalline, continuous Bi thin film via the vapor deposition (VD) method and found that the Bi thin film can exhibit broadband, ultrafast nonlinear optical response with low saturable intensity ranging from the near-infrared to mid-infrared spectral range under strong excitation. Moreover, we demonstrated that the Bi thin film was favorable to act as a nonlinear pulse modulator toward a high performance pulsed laser operating in optical communication and mid-infrared wavelengths. The experimental results highlight the prospects of Bi thin film as broadband pulsed modulators and may open new avenues toward advanced Bi-based broadband photonic devices.

6.
Sci Total Environ ; 687: 877-884, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31412491

RESUMO

With the increasing use of bisphenol F (BPF) as BPA alternative, BPF are widely distributed in multiple environment media. Our previous study demonstrated that BPF possess equivalent toxicity towards zebrafish as BPA, while its toxic mechanism remains largely unknown. To investigate the mechanisms mediating the developmental effects of BPF, zebrafish embryos were exposed to 0.0005, 0.5, and 5.0 mg/L BPF. Morphological examination indicated that BPF exposure led to depigmentation, decreased heart rate, inhibited spontaneous movement, hatch inhibition, and spinal deformation. Motor neuron-green fluorescence zebrafish assay indicated that exposure to 0.5 or 5.0 mg/L BPF affected embryonic motor neuron development, which is consistent with the spinal defect and spontaneous movement inhibition. Transcriptomic analysis showed that genes associated with the observed symptoms, including neuron development (ngln2a, socs3a, fosb), cardiac development (klf2a), and spinal deformation (ngs, col8a1a, egr2a), were down-regulated after exposure to either 0.0005 (environmental relevant concentration) or 0.5 mg/L BPF. This partially explained the mechanisms underlying the effects of BPF. In conclusion, BPF had the potential to affect zebrafish development even at environmental level through down-regulating associated genes.

8.
Biomater Sci ; 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31364616

RESUMO

The emergence of drug-resistant bacteria poses a serious threat to public health. The traditional antibiotics have specific intracellular targets and disinfect via chemical ways, which easily lead to the development of drug resistance, therefore, cationic peptides as promising antibiotic agents have attracted extensive attention due to their unique properties. Herein, we report a class of amphiphilic peptide-based pectinate polymers with primary amino groups. The polymers spontaneously self-assembled into the positively charged nanoparticles, which were evaluated and confirmed by scanning electron microscopy (SEM) and dynamic light scattering (DLS). Biological assays revealed that the nanoparticles showed broad-spectrum antibacterial efficacy against both Gram-positive and Gram-negative bacteria, exhibiting a MIC of 16 µg mL-1 against six clinical bacteria, namely, E. faecalis, S. aureus, MRSA, VRE, P. aeruginosa, and K. pneumonia, and three bacterial strains E. coli and E. coli producing NDM-1 and ImiS, and showed a sterilization rate of 95.6% and 94.7% on S. aureus and E. coli, respectively. Importantly, the nanoparticles did not result in drug-resistance for both the normal and drug-resistant bacteria tested after 14 passages and showed low toxicity on the mouse fibroblast cells (L929). The fluorescence staining, electrical conductivity, SEM, and surface plasmon resonance (SPR) characterization suggested that the nanoparticles initially bound to the surface of the bacteria, then pierced into the membranes of the bacteria with their phenyl groups, and finally disrupted the membranes, resulting in ions leaking out and thus exhibiting broad-spectrum antibacterial efficacy. This bactericidal mechanism that the nanoparticles employed does not lead the bacteria susceptible to developing drug resistance. This study provides a promising pathway for the development of the efficient antibacterial materials.

9.
Talanta ; 205: 120091, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450455

RESUMO

Many studies have demonstrated that metal-organic frameworks (MOFs) are universal fluorescence quenchers for DNA/RNA detection. Nevertheless, the structural stability of many MOFs is relatively weak, which limits their practical applications. Thus, it remains a great interest to develop constitutionally stable nano biosensor suitable for application in the complex environment. Herein, a new angle of nitrogen-doped porous carbon (NPC) obtained from MOFs-based precursors by virtue of a simple method was applied as a nano biosensor for the fluorescence detection of Zika virus (ZIKV) RNA sequences. The fluorescence signal capturing was carried out by using a charge-coupled device (CCD)-based imaging system. The NPC could adsorb TAMRA-tagged ZIKV RNA probe (P-DNA) to form P-DNA@NPC complex accompanied by substantial fluorescence quenching. Upon adding the complementary target RNA (T-RNA), the P-DNA could release from NPC by forming a double-stranded hybrid and induce the fluorescence recovery. The P-DNA@NPC complex was valid and reliable for ZIKV RNA sequences assay with a limit of detection (LoD) at 0.23 nM, which is superior to many of the previously reported fluorescent DNA sensors. Moreover, it could distinguish mismatched RNA and was effective in detecting ZIKV RNA sequences spiked in the human saliva sample. We envision that this study would offer an interesting new angle on the potential integrating application of carbon nanomaterials and CCD-based fluorescence imaging platform in the field of nucleic acid assay.

10.
Nanoscale ; 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31461104

RESUMO

Understanding the fundamental structure-property relationships of nanomaterials is critical for many catalytic applications as they comprise of the catalyst designing principles. Here, we develop efficient synthetic methods to prepare various MnO2 structures and investigate their catalytic performance as applied to the reverse Water Gas Shift (rWGS) reaction. We show that the support-free MnO derived from MnO2 1D, 2D and 3D nanostructures are highly selective (100% CO2 to CO), thermally stable catalysts (850 °C) and differently effective in the rWGS. Up to 50% conversion is observed, with a H2/CO2 feed-in ratio of 1 : 1. From both experiments and DFT calculations, we find the MnO2 morphology plays a critical role in governing the catalytic behaviors since it affects the predominant facets exposed under reaction conditions as well as the intercalation of K+ as a structural building block, substantially affecting the gas-solid interactions. The relative adsorption energy of reactant (CO2) and product (CO), ΔE = Eads(CO2) - Eads(CO), is found to correlate linearly with the catalytic activity, implying a structure-function relationship. The strong correlation found between Eads(CO2) - Eads(CO), or more generally, Eads(R) - Eads(P), and catalytic activity makes ΔE a useful descriptor for characterization of efficient catalysts involving gas-solid interactions beyond the rWGS.

11.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(7): 701-703, 2019 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-31302915

RESUMO

OBJECTIVE: To explore the genetic basis for a pedigree affected with Bartter's syndrome (BS). METHODS: Panel-based next-generation sequencing (NGS) was carried out to detect mutation in BS-related genes SLC12A1, KCNJ1, BSND and CLCNKB. Sanger sequencing of MAGED2 gene and chromosomal microarray analysis (CMA) were also performed on the patient. Suspected mutation was validated in her family members. RESULTS: No pathogenic mutation was detected by NGS, while a 0.152 Mb microdeletion at Xp11.21 (54 834 585-54 986 301) was found in the male fetus, which removed the entire coding region of the MAGED2 gene. His mother was a heterozygous carrier of the deletion. His father and sister did not carry the same deletion. CONCLUSION: The loss of the MAGED2 gene may underlie the BS in this pedigree.

12.
J Mater Sci Mater Med ; 30(7): 83, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31273466

RESUMO

Infection and encrustation limit the use of ureteral stent and to data no device can completely solve these complications. The Cu-bearing stainless steel is a novel material with properties of inhibiting infection and decreasing encrustation in vitro. In this work, ureteral stents were fabricated and implanted into the bladder of New Zealand rabbits, aiming to further investigate the effects of material on bacterial survival and growth as well as the implant related encrustation. Less adherent microbes and deposited crystals on Cu-bearing stainless steel stents were found, with significant differences in comparison with stainless steel stents, which further support the development of biofunctional ureteral stents.

13.
J Integr Neurosci ; 18(2): 193-196, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31321961

RESUMO

The two most common surgical interventions for spontaneous intracerebral hemorrhage in the basal ganglia of patients more than 65 years old are either minimally invasive puncture and drainage or craniotomy. This study aimed to compare the curative effects of these two procedures in such patients. A retrospective study of patients older than years with spontaneous intracerebral hemorrhage was conducted between January 2012 and December 2015. Of the 86 patients, 47 received minimally invasive puncture and drainage and 39 underwent craniotomy. One year after surgery no statistically significant difference was observed between the two groups with respect to: evacuation rate of the hematoma five days after the operation, volume of residual hematoma, occurrence of rebleeding, development of infectious meningitis, length of hospitalization, fatality, or Glasgow Outcome Scale and Barthel Index scores. However, the amount of blood loss during the procedure (P < 0.001), total cost of hospitalization (P = 0.004), and incidence of epilepsy (P = 0.045) were significantly higher for the craniotomy group than the minimally invasive puncture and drainage group. It was found that, in patients older than 65 years with basal ganglia hemorrhage, minimally invasive puncture and drainage is less invasive, more cost efficient and induces less bleeding during surgery than craniotomy.

14.
Eur J Med Chem ; 180: 367-382, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31325784

RESUMO

A series of hybrids of hydroxypyridinone and coumarin were rationally designed, synthesized and biologically evaluated for their iron ion chelating and MAO-B inhibitory activities. Most of the compounds displayed excellent iron ion chelating effects and moderate to good anti-MAO-B activities. Compound 27a exhibited the most potent activity against MAO-B, with an IC50 value of 14.7 nM. Importantly, 27a showed good U251 cell protective effect and significantly ameliorated the cognitive dysfunction of scopolamine-induced AD mice. Moreover, molecular docking was performed to elucidate the probable ligand-receptor interaction, and the structure-activity relationships were also summarized.

15.
Mater Sci Eng C Mater Biol Appl ; 103: 109718, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349483

RESUMO

Biodegradable Fe based alloys have been investigated for fracture fixation and cardiovascular support to overcome complications of permanent implants. This study was focused on the development of a new Fe-Mn-C-Cu alloy with antibacterial and anti-encrustation properties as a urinary implant material. The microstructure and mechanical properties of the alloy were studied. The degradation behavior, antibacterial and anti-encrustation properties were evaluated by immersion test, antibacterial test and encrustation test, respectively. The results showed that Fe-Mn-C-Cu alloy was a non-magnetic, biodegradable, anti-bacterial and anti-encrustation alloy that could inhibit the biofilm and stone formations on its surface through the dual effects of degradation and Cu ions release. The study revealed the preliminary mechanisms of anti-infection and anti-encrustation for Fe-Mn-C-Cu alloy due to the continuous release of Cu2+ ions, which provides a new idea for application of biodegradable Fe-based material and the treatment of urinary tract infections and stones in the urinary system.

16.
J Mater Sci Mater Med ; 30(7): 75, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31218519

RESUMO

Titanium implants easily suffer bacteria-related infections in clinic due to their inherent lack of self-protection ability. Therefore, a novel Ti-Cu alloy with good antibacterial activity has been developed as a new kind of implant material. This study focuses on a systematic evaluation of both cytocompatibility and osteogenesis activity of the Ti-Cu alloy in vitro. It was revealed that an addition of 5% Cu into pure Ti would not cause any negative effect on osteoblasts adhesion, proliferation and apoptosis cultured with Ti-Cu alloy. In addition, Ti-Cu alloy could significantly promote the osteogenic differentiation of MG 63 cells by upregulating the osteogenesis-related gene expressions including alkaline phosphatase (ALP), Collagen I (Colla I), osteopontin (OPN) and osteocalcin (OCN). These promising results suggest that the Ti-Cu alloy has great potential to be used as a multi-functional titanium implant for clinical applications.

17.
Asian J Surg ; 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31229360

RESUMO

OBJECTIVE: To compare robot-assisted surgery and conventional laparoscopy for gynecologic oncology regarding intra- and post-operative outcomes. METHODS: A retrospective study was performed on consecutive patients with gynecologic oncology from February 2014 to October 2017 at Gansu Provincial Hospital, China. Multivariable linear and logistic regression models were performed to explore the difference between two surgeries in the surgical outcomes after adjusting for potential confounders. RESULTS: 276 women were included in this study: 153 robot-assisted surgeries and 123 conventional laparoscopies. The multivariable linear regression model showed that robot-assisted surgery was longer operative time [coefficient (coef), 33.76; 95% CI, 12.47, 55.05; P = 0.002) ], higher lymph node yield (coef, 10.41; 95% CI, 7.47, 13.35; P < 0.001), shorter time to early post-operative feeding (coef, -1.09; 95% CI, -1.33, -0.84; P < 0.001) and less post-operative drainage volume (coef, -368.77; 95% CI, -542.46, -195.09; P < 0.001) than conventional laparoscopy. However, no difference was observed between the two surgeries regarding the estimated blood loss (P > 0.05). The multivariable logistic regression model showed that post-operative complications were similar between robot-assisted surgery and conventional laparoscopy (P > 0.05). CONCLUSION: Robot-assisted surgery was superior to conventional laparoscopy regarding intra- and post-operative outcomes for gynecologic oncology.

18.
Sci Rep ; 9(1): 8271, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31164661

RESUMO

The MSWI fly ash which contains a large number of heavy metal substances is a subsidiary product of waste incineration power generation technology. If the MSWI fly ash is disposed improperly, heavy metal pollutants will pose a great threat to environmental safety and human health. Based on the technology of electrokinetic remediation, the feasibility of removing heavy metal pollutants from the MSWI fly ash using a modified electrokinetic remediation device - cylinder device was evaluated in this study. Differing from the traditional cuboid device with the volume ratio of the cathode chamber to the anode chamber being 1:1, the volume ratio of the cathode chamber to the anode chamber of the cylinder device was 16:1. Changes in parameters, such as pH values and conductivity in the cathode and the anode chambers as well as current and voltage in the sample area were analysed under the voltage gradient of 2 V/cm. After the experiment, the average removal efficiencies for Zn, Pb, Cd and Cu in the sample area were 53.2%, 31.4%, 42.3% and 30.7%, respectively. It indicates that the cylinder device is effective in removing heavy metals from the MSWI fly ash. Adopting the cylinder device for the experimental study on the electrokinetic remediation technology could provide a better way of thinking for the future engineering practices and applications.

19.
Comput Intell Neurosci ; 2019: 4328653, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31182958

RESUMO

Recently, machine learning, especially deep learning, has been a core algorithm to be widely used in many fields such as natural language processing, speech recognition, object recognition, and so on. At the same time, another trend is that more and more applications are moved to wearable and mobile devices. However, traditional deep learning methods such as convolutional neural network (CNN) and its variants consume a lot of memory resources. In this case, these powerful deep learning methods are difficult to apply on mobile memory-limited platforms. In order to solve this problem, we present a novel memory-management strategy called mmCNN in this paper. With the help of this method, we can easily deploy a trained large-size CNN on any memory size platform such as GPU, FPGA, or memory-limited mobile devices. In our experiments, we run a feed-forward CNN process in some extremely small memory sizes (as low as 5 MB) on a GPU platform. The result shows that our method saves more than 98% memory compared to a traditional CNN algorithm and further saves more than 90% compared to the state-of-the-art related work "vDNNs" (virtualized deep neural networks). Our work in this paper improves the computing scalability of lightweight applications and breaks the memory bottleneck of using deep learning method on memory-limited devices.

20.
Mol Cell Endocrinol ; 494: 110490, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31207271

RESUMO

Diabetic nephropathy (DN) is a progressive disease, the main pathogeny of which is podocyte injury. As a calcium-dependent serine/threonine protein kinase involved in podocyte injury, protein kinase C isoform α (PKCα) was reported to regulate the phosphorylation of p66SHC. However, the role of PKCα/p66SHC in DN remains unknown. Klotho, an anti-aging protein with critical roles in protecting kidney, is expressed predominantly in the kidney and secreted in the blood. Nonetheless, the mechanism underlying amelioration of podocyte injury by Klotho in DN remains unclear. Our data showed that Klotho was decreased in STZ-treated mice and was further declined in diabetic KL ± mice. As expected, Klotho deficiency aggravated diabetes-induced proteinuria and podocyte injury, accompanied by the activation of PKCα and p66SHC. In contrast, overexpression of Klotho partially ameliorated PKCα/p66SHC-mediated podocyte injury and proteinuria. In addition, in vitro experiments showed that activation of PKCα and subsequently increased intracellular reactive oxygen species (ROS) was involved in podocytic apoptosis induced by high glucose (HG), which could be partially reversed by Klotho. Hence, we conclude that Klotho might inhibit PKCα/p66SHC-mediated podocyte injury in diabetic nephropathy.

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