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1.
Front Neurol ; 15: 1383980, 2024.
Article En | MEDLINE | ID: mdl-38863508

Objective: Spinal schwannomas are the most common intradural extramedullary tumors, and their complete removal is recommended to avoid tumor recurrence. Although laminoplasty provides a sufficient window for tumor resection, this approach may increase tissue trauma and cause postoperative instability compared with unilateral hemilaminectomy. This study aimed to compare the efficacy and clinical outcomes of the two approaches. Materials and methods: We included 100 consecutive patients who underwent unilateral hemilaminectomy or laminoplasty for resection of spinal schwannomas between January 2015 and February 2023. The patients' baseline characteristics, including sex, age, tumor location, percentage of tumor occupying the intradural space, operative time, postoperative length of hospital stay, intraoperative bleeding volume, visual analog scale score, and neurologic results, were retrospectively analyzed. Results: Hemilaminectomy patients who underwent unilateral hemilaminectomy had smaller intraoperative bleeding (p = 0.020) volume, shorter operative time (p = 0.012), and shorter postoperative length of hospital stay (p = 0.044). The mean VAS scores at the last follow-up were similar between the two groups (p = 0.658). Although the postoperative McCormick and Karnofsky Performance scores were not significantly different between the laminoplasty and unilateral hemilaminectomy groups (p = 0.687 and p = 0.649, respectively), there was a statistically significant improvement based on postoperative neurological results compared to preoperative neurological results for both groups. The incidence of postoperative complications was 5% and 11.7% in the unilateral hemilaminectomy and laminoplasty groups, respectively (p = 0.308). Conclusions: For spinal schwannoma resection, unilateral hemilaminectomy has more advantages than laminoplasty, including a shorter postoperative hospital stay, faster procedure, and less intraoperative blood loss while achieving the same desired result.

2.
Phytomedicine ; 132: 155812, 2024 Jun 13.
Article En | MEDLINE | ID: mdl-38905845

BACKGROUND: Inflammatory bowel disease (IBD) represents a significant global health challenge, and there is an urgent need to explore novel therapeutic interventions. Natural products have demonstrated highly promising effectiveness in the treatment of IBD. PURPOSE: This study systematically reviews the latest research advancements in leveraging natural products for IBD treatment. METHODS: This manuscript strictly adheres to the PRISMA guidelines. Relevant literature on the effects of natural products on IBD was retrieved from the PubMed, Web of Science and Cochrane Library databases using the search terms "natural product," "inflammatory bowel disease," "colitis," "metagenomics", "target identification", "drug delivery systems", "polyphenols," "alkaloids," "terpenoids," and so on. The retrieved data were then systematically summarized and reviewed. RESULTS: This review assessed the different effects of various natural products, such as polyphenols, alkaloids, terpenoids, quinones, and others, in the treatment of IBD. While these natural products offer promising avenues for IBD management, they also face challenges in terms of clinical translation and drug discovery. The advent of metagenomics, single-cell sequencing, target identification techniques, drug delivery systems, and other cutting-edge technologies heralds a new era in overcoming these challenges. CONCLUSION: This paper provides an overview of current research progress in utilizing natural products for the treatment of IBD, exploring how contemporary technological innovations can aid in discovering and harnessing bioactive natural products for the treatment of IBD.

3.
Heliyon ; 10(10): e30710, 2024 May 30.
Article En | MEDLINE | ID: mdl-38765023

In this paper, in order to establish the energy separation mechanism of the vortex tube, the hydrodynamic behavior of the compressible fluid in the asymmetric cavity space is investigated, and a numerical model of the trajectory deflection behavior is deduced and established; in order to form the optimal design method of the structural parameters of the vortex tube, the force situation of the fluid microelements entering different regions of the vortex chamber of the vortex tube is analyzed, and the trajectory deflection equations are corrected by combining with the expansion behavior of the fluid and the characterizing equations of vortex strength, transportability, and vortex initiation characteristics are given. The characterization equations of vortex strength, transportability and vortex initiation characteristics are given, and the numerical simulation of their influence parameters is carried out; in order to realize the prediction of the vortex tube performance of a given structure, the multifactor Pearson thermodynamic map is used to correlate and analyze the experimental data of vortex tubes reported publicly in the past years, and the polynomial regression equations are designed and established for the prediction of the vortex tube's energy separation effect and the confidence level and the degree of coincidence of the prediction results are examined. The confidence level and degree of agreement of the prediction results were examined. It is found that: the trajectory deflection motion of the compressible fluid in the asymmetric cavity space is the result of the combined effect of structural air pressure bias and the expansion behavior of the incident fluid; in order to improve the vortex strength in the vortex tube, the vortex initiation chamber space should be as small as possible; the increase of the diameters of the hot-end pipe and the cold-end pipe is conducive to the enhancement of vortex strength, but at the same time, it weakens the vortex transport in the heat pipe; the vortex initiation chamber size has a negative correlation with the hot-end temperature rise, and the inlet fluid pressure has a The negative correlation between the size of the vortex chamber and the temperature rise at the hot end, the positive correlation between the increase of inlet fluid pressure and the resulting temperature rise, and the strong correlation between the inlet fluid pressure and the friction coefficient on the effect of energy separation; the predictive equations for the effect of energy separation obtained by the fitting are in good agreement with the real situation.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 281: 121567, 2022 Nov 15.
Article En | MEDLINE | ID: mdl-35810673

Amines levels present important indicative value in food safety and human health. Although they are involved in some normal physiological responses of the organism, their overproduction or intake may cause pathological responses. Herein, we report a recyclable visual packaging bag for volatile amines detections based on the naphthylamide derivative N-S and its positive PL characteristics. Specifically, handmade test strips based on compound N-S have been applied to fish freshness labeling, and the cyclic fumigation experiment shows its restorable PL effect and efficiency. The possible PL transfer mechanism of naphthylamide derivative N-S is uncovered by the density functional theory (DFT) calculation and titration mass spectrometer and 1H NMR. This work expands a conjugation in a molecule by hydrogen-bond activated ESIPT (H-ESIPT) and provides a portable detection method for volatile amines detection.


Amines , Fluorescent Dyes , Amines/chemistry , Animals , Fluorescent Dyes/chemistry , Humans , Hydrogen , Hydrogen Bonding , Naphthalimides
5.
Int J Biol Macromol ; 163: 1719-1728, 2020 Nov 15.
Article En | MEDLINE | ID: mdl-32971170

In this study, inhibitory kinetics of Nuciferine and Methyl Ganoderate extrated from Lotus Leaves and Ganoderma lucidum on Mucor miehei Lipase were studied first. The molecular structure of Nuciferine and Methyl Ganoderate were determined. The inhibitory effects of two extracts on lipase were reversible, with the IC50 values of 0.194 and 0.332 mg/mL, respectively. The inhibition kinetic analysis by Lineweaver-Burk plots showed that they were a mixed-type inhibitor of lipase, with inhibition constants KI of 0.16 and 0.29 mg/mL, and KIS of 0.36 and 0.49 mg/mL, respectively. Results of spectral analysis showed that the UV absorption and the molecule fluorescence spectrum of the lipase hydrolyzate were significantly decreased after the inhibitor was added. The molecular docking further suggested that the interaction site between the active substance and inhibitor was located in an α-helix and a ß-sheet of the lipase, and the lipase active site was interfered by the inhibitor near the cap structure. In addition, the proliferation and differentiation of 3 T3-L1 preadipocytes were inhibited by two extracts. Total triglycerides and cholesterol were significantly reduced in the cells. The results confirmed that Nuciferine and Methyl Ganoderate can be used as potential obesity treatment drugs.


Aporphines/pharmacology , Lipase/metabolism , Rhizomucor/drug effects , Triterpenes/pharmacology , 3T3-L1 Cells , Adipocytes/drug effects , Adipogenesis/drug effects , Animals , Anti-Obesity Agents/pharmacology , Catalytic Domain/drug effects , Cell Differentiation/drug effects , Cell Line , Cell Proliferation/drug effects , Cholesterol/metabolism , Kinetics , Mice , Molecular Docking Simulation/methods , Obesity/drug therapy , Obesity/metabolism , Protein Conformation, alpha-Helical/drug effects , Protein Conformation, beta-Strand/drug effects , Reishi/chemistry , Triglycerides/metabolism
6.
Sci Total Environ ; 725: 138383, 2020 Jul 10.
Article En | MEDLINE | ID: mdl-32283309

Microplastic (MP) pollution is a growing environmental problem in the global oceans. However, there is relatively little evidence of the extent of MP pollution around remote islands, such as coral reefs, in the open ocean. In this study, we conducted a large-scale investigation of MP pollution in the surface waters around the remote uninhabited coral reefs of Nansha Islands in South China Sea. Microplastics were widespread in the surface waters with an average abundance of 0.0556 ± 0.0355 items/m3, although this varied among the coral reefs. The MPs were predominantly composed of polypropylene (PP) and polyethylene (PE), and > 70% of them were <3 mm in size. Fragments and fibers comprised the most common MP types. The similarity between macro plastic and MP compositions provided evidence for the tracing of MP sources in the study area. The main pollutants (transparent PP fibers and PE fibers) around these remote coral reefs may originate from fishing gear abrasions. The plastic waste released from nearby residential islands and high-intensity fishing activities around Nansha Islands likely represented important local sources. Overall, the abundance of MPs found in the surface waters surrounding these remote coral reefs in the South China Sea was relatively low; however, these levels of MP pollution should not be disregarded given the importance of coral reef ecosystems.

7.
ACS Appl Mater Interfaces ; 11(33): 30045-30052, 2019 Aug 21.
Article En | MEDLINE | ID: mdl-31342743

Van der Waals heterostructures formed by stacking of various two-dimensional materials are promising in electronic applications. However, the performances of most reported electronic devices based on van der Waals heterostructures are far away from those of existing (Si, Ge, and III-V bulk material based) technologies. Here, we report high-performance heterostructure devices based on vertically stacked tungsten diselenide and tin diselenide. Due to the unique band alignment and the atomic thickness of the material, both charge carrier transport and energy barrier can be effectively modulated by the applied electrical field. As a result, the heterostructure devices show superb characteristics, with a high current on/off ratio of ∼3 × 108, an average subthreshold slope of 126 mV/dec over 5 dec of current change due to band-to-band tunneling, an ultrahigh rectification ratio of ∼3 × 108, and a current density of more than 104 A/cm2. Furthermore, a small signal half-wave rectifier circuit based on a majority-carrier-transport-dominated diode is successfully demonstrated, showing great potential in future high-speed electronic applications.

8.
Zhongguo Zhong Yao Za Zhi ; 41(21): 3975-3981, 2016 Nov.
Article Zh | MEDLINE | ID: mdl-28929684

A novel method combining ultra-high performance liquid chromatography (UHPLC) fingerprint and simultaneous quantitative analysis of eight phenolic components was developed and validated for quality evaluation of Tetrastigma hemsleyanum leaves. For fingerprint analysis, 15 peaks were selected as the common peaks to evaluate the similarities among 41 batches of T. hemsleyanum leaves collected from different regions. Additionally, simultaneous quantification of eight markers, including neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, isoorientin, orientin, vitexin-2-O-rhamnoside,vitexin and isovitexin, was performed and the obtained data demonstrated that our method has achieved desired linearity, precision and accuracy. Clustering statistical analysis was further application in T. hemsleyanum leaves from different regions. The results indicated that new approach conbine ultra-high performance liquid chromatography (UHPLC) fingerprint and simultaneous quantitative analysis of eight phenolic components was applicable in quality control of T. hemsleyanum leaves.


Phenols/analysis , Plant Leaves/chemistry , Vitaceae/chemistry , Chromatography, High Pressure Liquid , Phytochemicals/analysis
9.
ACS Nano ; 9(5): 4900-10, 2015 May 26.
Article En | MEDLINE | ID: mdl-25877681

Transition metal dichalcogenides are relevant for electronic devices owing to their sizable band gaps and absence of dangling bonds on their surfaces. For device development, a controllable method for doping these materials is essential. In this paper, we demonstrate an electrostatic gating method using a solid polymer electrolyte, poly(ethylene oxide) and CsClO4, on exfoliated, multilayer 2H-MoTe2. The electrolyte enables the device to be efficiently reconfigured between n- and p-channel operation with ON/OFF ratios of approximately 5 decades. Sheet carrier densities as high as 1.6 × 10(13) cm(-2) can be achieved because of a large electric double layer capacitance (measured as 4 µF/cm(2)). Further, we show that an in-plane electric field can be used to establish a cation/anion transition region between source and drain, forming a p-n junction in the 2H-MoTe2 channel. This junction is locked in place by decreasing the temperature of the device below the glass transition temperature of the electrolyte. The ideality factor of the p-n junction is 2.3, suggesting that the junction is recombination dominated.

10.
Sci Rep ; 4: 5548, 2014 Jul 07.
Article En | MEDLINE | ID: mdl-24998222

Graphene/silicon CMOS hybrid integrated circuits (ICs) should provide powerful functions which combines the ultra-high carrier mobility of graphene and the sophisticated functions of silicon CMOS ICs. But it is difficult to integrate these two kinds of heterogeneous devices on a single chip. In this work a low temperature process is developed for integrating graphene devices onto silicon CMOS ICs for the first time, and a high performance graphene/CMOS hybrid Hall IC is demonstrated. Signal amplifying/process ICs are manufactured via commercial 0.18 um silicon CMOS technology, and graphene Hall elements (GHEs) are fabricated on top of the passivation layer of the CMOS chip via a low-temperature micro-fabrication process. The sensitivity of the GHE on CMOS chip is further improved by integrating the GHE with the CMOS amplifier on the Si chip. This work not only paves the way to fabricate graphene/Si CMOS Hall ICs with much higher performance than that of conventional Hall ICs, but also provides a general method for scalable integration of graphene devices with silicon CMOS ICs via a low-temperature process.

11.
Sci Rep ; 3: 1207, 2013.
Article En | MEDLINE | ID: mdl-23383375

Hall elements are by far the most widely used magnetic sensor. In general, the higher the mobility and the thinner the active region of the semiconductor used, the better the Hall device. While most common magnetic field sensors are Si-based Hall sensors, devices made from III-V compounds tend to favor over that based on Si. However these devices are more expensive and difficult to manufacture than Si, and hard to be integrated with signal-processing circuits for extending function and enforcing performance. In this article we show that graphene is intrinsically an ideal material for Hall elements which may harness the remarkable properties of graphene, i.e. extremely high carrier mobility and atomically thin active body, to create ideal magnetic sensors with high sensitivity, excellent linearity and remarkable thermal stability.

12.
Nat Commun ; 3: 699, 2012 Feb 28.
Article En | MEDLINE | ID: mdl-22426220

Large single-crystal graphene is highly desired and important for the applications of graphene in electronics, as grain boundaries between graphene grains markedly degrade its quality and properties. Here we report the growth of millimetre-sized hexagonal single-crystal graphene and graphene films joined from such grains on Pt by ambient-pressure chemical vapour deposition. We report a bubbling method to transfer these single graphene grains and graphene films to arbitrary substrate, which is nondestructive not only to graphene, but also to the Pt substrates. The Pt substrates can be repeatedly used for graphene growth. The graphene shows high crystal quality with the reported lowest wrinkle height of 0.8 nm and a carrier mobility of greater than 7,100 cm(2) V(-1) s(-1) under ambient conditions. The repeatable growth of graphene with large single-crystal grains on Pt and its nondestructive transfer may enable various applications.

13.
ACS Nano ; 5(6): 5031-7, 2011 Jun 28.
Article En | MEDLINE | ID: mdl-21528892

High-performance graphene field-effect transistors (G-FETs) are fabricated with carrier mobility of up to 5400 cm(2)/V·s and top-gate efficiency of up to 120 (relative to that of back gate with 285 nm SiO(2)) simultaneously through growing high-quality Y(2)O(3) gate oxide at high oxidizing temperature. The transconductance normalized by dimension and drain voltage is found to reach 7900 µF/V·s, which is among the largest of the published graphene FETs. In an as-fabricated graphene FET with a gate length of 310 nm, a peak transconductance of 0.69 mS/µm is realized, but further improvement is seriously hindered by large series resistance. Benefiting from highly efficient gate control over the graphene channel, the Dirac point voltage of the graphene FETs is shown to be designable via simply selecting a gate metal with an appropriate work function. It is demonstrated that the Dirac point voltage of the graphene FETs can be adjusted from negative to positive, respectively, via changing the gate material from Ti to Pd.

14.
ACS Nano ; 5(4): 2512-9, 2011 Apr 26.
Article En | MEDLINE | ID: mdl-21370813

A novel self-aligned U-gate structure for carbon nanotube (CNT) field-effect transistors (FETs) is introduced and shown to yield excellent dc properties and high reproducibility that are comparable with that of the best CNT FETs based on the previously developed self-aligned device structures. In particular the subthreshold swing of the U-gate FET is 75 mV/dec and the drain-induced barrier lowering is effectively zero, indicating that the electrostatic potential of the whole CNT channel is most efficiently controlled by the U-gate and that the CNT device is a well-behaved FET. Moreover the high-frequency response of the U-gate FET is investigated, and the parasitic capacitance of the device is measured and shown to be one magnitude smaller than that of the previously developed self-aligned device structures. Direct frequency domain measurements show that the U-gate CNT FETs can operate up to 800 MHz, which is also higher than previously reported values. The large improvement in the device high-frequency behavior is largely due to the replacement of the high-κ dielectric material between the source/drain and the gate by a vacant space with κ ≈ 1, and the significant reduction in the device parasitic capacitance renders the U-gate CNT FETs promising for rf applications.

15.
ACS Nano ; 5(3): 2340-7, 2011 Mar 22.
Article En | MEDLINE | ID: mdl-21323320

A high-quality Y2O3 dielectric layer has been grown directly on graphene and used to fabricated top-gate graphene field-effect transistors (FETs), and the thickness of the dielectric layer has been reduced continuously down to 3.9 nm with an equivalent oxide thickness (EOT) of 1.5 nm and excellent insulativity. By measuring CV characteristics of two graphene FETs with different gate oxide thicknesses, the oxide capacitance and quantum capacitance are retrieved directly from the experimental CV data without introducing any additional fitting process and parameters, yielding a relative dielectric constant of κ=10 for Y2O3 on graphene and an oxide capacitance of about 2.28 µF/cm2. It is found that for a rather large gate voltage range, this oxide capacitance is comparable and sometimes even larger than the quantum capacitance of graphene. Since the total gate capacitance is determined by the smaller of the oxide and quantum capacitance, our results show that not much further improvement can be gained via further vertical scaling down of the gate oxide, suggesting that Y2O3 may be the ultimate dielectric material for graphene. It is also shown that the Y2O3 gate dielectric layer with EOT of 1.5 nm may also satisfy the ultimate lateral scaling requirement on the gate length of graphene FET and be used effectively to control a graphene FET with a gate length as small as 1 nm.


Graphite/chemistry , Nanostructures/chemistry , Transistors, Electronic , Electric Capacitance , Equipment Design , Equipment Failure Analysis , Materials Testing
16.
Nano Lett ; 10(6): 2024-30, 2010 Jun 09.
Article En | MEDLINE | ID: mdl-20455575

High-quality yttrium oxide (Y(2)O(3)) is investigated as an ideal high-kappa gate dielectric for carbon-based electronics through a simple and cheap process. Utilizing the excellent wetting behavior of yttrium on sp(2) carbon framework, ultrathin (about few nm) and uniform Y(2)O(3) layers have been directly grown on the surfaces of carbon nanotube (CNT) and graphene without using noncovalent functionalization layers or introducing large structural distortion and damage. A top-gate CNT field-effect transistor (FET) adopting 5 nm Y(2)O(3) layer as its top-gate dielectric shows excellent device characteristics, including an ideal subthreshold swing of 60 mV/decade (up to the theoretical limit of an ideal FET at room temperature). The high electrical quality Y(2)O(3) dielectric layer has also been integrated into a graphene FET as its top-gate dielectric with a capacitance of up to 1200 nF/cm(2), showing an improvement on the gate efficiency and on state transconductance of over 100 times when compared with that of its back-gate counterpart.

17.
Ying Yong Sheng Tai Xue Bao ; 21(12): 3231-8, 2010 Dec.
Article Zh | MEDLINE | ID: mdl-21443014

A comparative proteomics analysis was performed to identify the molecular response of a rice cultivar (Oryza sative cv. 'IRRI71331') with high phosphorous (P) uptake efficiency to low P stress. The hydroponically grown rice plants were provided with two levels of P (0.5 mg x L(-1) and 10 mg x L(-1)) supplied in quarter strength Kimura solution, and the root total proteins extracted on the 3rd and 6th day of treatments were separated by two-dimensional gel electrophoresis (2-DE). Comparing with the control (10 mg x L(-1) of P), a total of 29 protein spots under low P stress (0.5 mg x L(-1)) showed differences in their relative abundance, among which, 17 were higher, 11 were lower, and 1 was novel on the 3rd day, and 8 were induced, 19 were suppressed, 1 was disappeared, and 1 had no obvious change on the 6th day. Ten differentially expressed protein spots were identified by MALDI-TOF/MS, and searched in protein databases. According to the putative functions, the identified proteins were classified into four groups, i.e., signal transduction (glycine-rich RNA-binding protein, phosphate starvation response regulator-like), gene expression (putative pre-mRNA splicing factor, putative AAA-metalloprotease), metabolism (adenylosuccinate lyase, serpin, S-adenosylmethionine synthetase, MYB transcription factor-like protein), and ion transport (cation-transporting ATPase, sarcoplasmic reticulum protein). The identified proteins were involved in various physiological responses to enhance stress resistance, such as signal recognition and transduction, RNA cleavage, degradation of denatured protein, and ion transportation and cellular ion balance. The serine protease inhibitor and S-adenosylmethionine synthetase and the MYB transcription factor-like protein, which were the key proteins associated with P deficiency--tolerance of other species, were affected by the same stress for rice. The results indicated that the tolerance to low P stress was controlled by a complex signal transduction and metabolism regulation network in rice root system.


Oryza/metabolism , Phosphorus/metabolism , Plant Proteins/analysis , Plant Roots/metabolism , Stress, Physiological , Electrophoresis, Gel, Two-Dimensional/methods , Metabolic Networks and Pathways , Oryza/chemistry , Oryza/growth & development , Phosphorus/analysis , Plant Roots/chemistry , Proteomics/methods , Signal Transduction
18.
Nano Lett ; 8(11): 3696-701, 2008 Nov.
Article En | MEDLINE | ID: mdl-18947214

Near ballistic n-type single-walled carbon nanotube field-effect transistors (SWCNT FETs) have been fabricated with a novel self-aligned gate structure and a channel length of about 120 nm on a SWCNT with a diameter of 1.5 nm. The device shows excellent on- and off-state performance, including high transconductance of up to 25 microS, small subthreshold swing of 100 mV/dec, and gate delay time of 0.86 ps, suggesting that the device can potentially work at THz regime. Quantitative analysis on the electrical characteristics of a long channel device fabricated on the same SWCNT reveals that the SWCNT has a mean-free-path of 191 nm, and the electron mobility of the device reaches 4650 cm(2)/Vs. When benchmarked by the metric CV/ I vs Ion/Ioff, the n-type SWCNT FETs show significantly better off-state leakage than that of the Si-based n-type FETs with similar channel length. An important advantage of this self-aligned gate structure is that any suitable gate materials can be used, and in particular it is shown that the threshold voltage of the self-aligned n-type FETs can be adjusted by selecting gate metals with different work functions.

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