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1.
Phys Rev E ; 104(4-2): 045209, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34781465

ABSTRACT

An electron heating mechanism based on a resonance between the cyclotron motion of electrons and the radio frequency sheath oscillations is reported in weakly magnetized capacitively coupled plasmas at low pressure. If half of the electron cyclotron period coincides with the radio frequency period, then electrons will coherently collide with the expanding sheath and gain substantial energy, which enhances the plasma density. A relation between the magnetic field and the driving frequency is found to characterize this resonance effect and the kinetics of electrons are revealed at resonance conditions for various driving frequencies.

2.
Coron Artery Dis ; 32(2): 105-111, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33060524

ABSTRACT

OBJECTIVES: The purpose of this study was to evaluate the association of diabetes mellitus (DM) with neointimal formation after implantation of second-generation drug-eluting stent (DES) visualized by optical coherence tomography (OCT). METHODS: Patients with single de novo coronary artery disease treated with second-generation DES between June 2014 and June 2017 in our department underwent OCT examination at 1-year follow-up and were enrolled in this retrospective study. The primary end point was in-stent mean neointimal thickness (MNT), and secondary end points included uncovered stent strut, minimal lumen area (MLA), neointimal burden, neointimal hyperplasia (NIH) patterns and stent thrombosis (ST) after 1 year of OCT follow-up. RESULTS: A total of 68 patents with DM (DM group) and 216 patients without DM (non-DM group) were enrolled. At 1-year follow-up, the DM group compared with the non-DM group, showed: MNT [160 (85-245) µm vs. 120 (60-220) µm, P = 0.038] and neointimal burden [21.4 (8.3-30.1)% vs. 14.0 (5.7-26.1)%, P = 0.023] to be significantly increased. Concurrently, MLA [4.60 (3.53-6.06) mm vs. 5.76 (4.28-7.20) mm2, P = 0. 0.002] was significantly reduced. Interestingly, the degree of uncovered struts (7.3 ± 7.1% vs. 7.7 ± 6.7%, P = 0.704), NIH patterns (P = 0.984), and ST (7.9% vs. 7.4%, P = 0.88) were comparable between the two groups. After propensity score matching, the MNT [160 (90-240) µm vs. 110 (60-220) µm, P = 0.048] and neointimal burden [21.4 (8.3-30.1)% vs. 15.4 (5.6-26.3)%, P = 0.044] remained significantly different in the DM compared to the non-DM group. CONCLUSION: DM leads to significant increase in MNT and neointimal burden even with second-generation DES, nevertheless stent strut coverage, ST and NIH characteristics remained comparable among the cohorts at 1-year.


Subject(s)
Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/drug therapy , Diabetes Mellitus , Drug-Eluting Stents , Neointima/pathology , Tomography, Optical Coherence , Aged , Female , Humans , Male , Middle Aged , Propensity Score , Retrospective Studies
3.
Chin Med J (Engl) ; 133(20): 2415-2421, 2020 Oct 20.
Article in English | MEDLINE | ID: mdl-32889912

ABSTRACT

BACKGROUND: Acute coronary syndromes mainly result from abrupt thrombotic occlusion caused by atherosclerotic vulnerable plaques (VPs) that suddenly rupture or erosion. Fibrous cap thickness (FCT) is a major determinant of the propensity of a VP to rupture and is recognized as a key factor. The intensive use of statins is known to have the ability to increase FCT; however, there is a risk of additional adverse effects. However, lower dose statin with ezetimibe is known to be tolerable by patients. The present study aimed to investigate the effect of intensive statin vs. low-dose stain + ezetimibe therapy on FCT, as evaluated using optical coherence tomography. METHOD: Patients who had VPs (minimum FCT <65 µm and lipid core >90°) and deferred from intervention in our single center from January 2014 to December 2018 were included in the trial. They were divided into the following two groups: intensive statin group (rosuvastatin 15-20 mg or atorvastatin 30-40 mg) and combination therapy group (rosuvastatin 5-10 mg or atorvastatin 10-20 mg + ezetimibe 10 mg). At the 12-month follow-up, we compared the change in the FCT (ΔFCT%) between the two groups and analyzed the association of ΔFCT% with risk factors. Fisher exact test was used for all categorical variables. Student's t test or Mann-Whitney U-test was used for analyzing the continuous data. The relationship between ΔFCT% and risk factors was analyzed using linear regression analysis. RESULT: Total 53 patients were finally enrolled, including 26 patients who were in the intensive statin group and 27 who were in the combination therapy group. At the 12-month follow-up, the serum levels of total cholesterol (TC), total triglyceride, low-density lipoprotein (LDL-C), hypersensitive C-reactive protein (hs-CRP), and lipoprotein-associated phospholipase A2 (Lp-PLA2) levels were reduced in both the groups. The ΔTC%, ΔLDL-C%, and ΔLp-PLA2% were decreased further in the combination therapy group. FCT was increased in both the groups (combination treatment group vs. intensive statin group: 128.89 ±â€Š7.64 vs. 110.19 ±â€Š7.00 µm, t = -9.282, P < 0.001) at the 12-month follow-up. The increase in ΔFCT% was more in the combination therapy group (123.46% ±â€Š14.05% vs. 91.14% ±â€Š11.68%, t = -9.085, P < 0.001). Based on the multivariate linear regression analysis, only the serum Lp-PLA2 at the 12-month follow-up (B = -0.203, t = -2.701, P = 0.010), ΔTC% (B = -0.573, t = -2.048, P = 0.046), and Δhs-CRP% (B = -0.302, t = -2.963, P = 0.005) showed an independent association with ΔFCT%. CONCLUSIONS: Low-dose statin combined with ezetimibe therapy maybe provide a profound and significant increase in FCT as compared to intensive statin monotherapy. The reductions in Lp-PLA2, ΔTC%, and Δhs-CRP% are independently associated with an increase in FCT.


Subject(s)
Anticholesteremic Agents , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Plaque, Atherosclerotic , Anticholesteremic Agents/therapeutic use , Drug Therapy, Combination , Ezetimibe/therapeutic use , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Plaque, Atherosclerotic/diagnostic imaging , Plaque, Atherosclerotic/drug therapy , Rosuvastatin Calcium/therapeutic use , Tomography, Optical Coherence , Treatment Outcome
4.
Biomed Pharmacother ; 98: 157-164, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29253763

ABSTRACT

Crocetin is a natural product possessing extraordinary therapeutic effects for various diseases. However, its extremely low solubility limits its application greatly. Conjugation of organic compounds containing heteroatoms such as N to poor soluble molecules can help the synthesized derivative to form stable hydrogen bonds by lowering the salvation energy, which will improve the solubility of the synthesized compounds. Herein, crocetin was modified by conjugating with piperidyl, diethylin and benzylamine to improve their solubility and bioactivities. In the present study, the conjugation of crocetin with piperidyl, diethylin and benzylamine and their influence on the solubility and the pharmacological effects of crocetin were investigated. With the described strategy, crocetin derivatives were synthesized and their structures were elucidated by 1H NMR, 13C NMR and UPLC-MS spectroscopic analysis. The solubility of crocetin and its derivatives were identified. Upon that, the pharmacological effects of the crocetin derivatives on the tumor and inflammation treatment were investigated. It was shown that, in contrast to crocetin, of which, the solubility and pharmacological effects were low and limited, the synthesized compounds have significantly higher solubility and possess broad spectrum of anticancer effects in multiple tumor cell lines, including B16F10, MCF-7, A549 and SKOV3, as well as enhanced anti-inflammation efficacy in macrophage (RAW264.7) without causing cells damage. Conjugation of piperidyl, diethylin and benzylamine with the crocetin was demonstrated to be a highly efficient strategy to improve the solubility of crocetin. The synthesized crocetin derivatives were shown the promising therapeutics for the tumor and inflammation treatment with high safety.


Subject(s)
Anticarcinogenic Agents/chemical synthesis , Anticarcinogenic Agents/therapeutic use , Carotenoids/chemical synthesis , Carotenoids/therapeutic use , Melanoma, Experimental/drug therapy , A549 Cells , Animals , Anticarcinogenic Agents/pharmacology , Apoptosis/drug effects , Apoptosis/physiology , Carotenoids/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Cell Survival/physiology , Dose-Response Relationship, Drug , Gardenia , Humans , Inflammation/drug therapy , Inflammation/metabolism , MCF-7 Cells , Melanoma, Experimental/metabolism , Mice , Plant Extracts/chemical synthesis , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , RAW 264.7 Cells , Vitamin A/analogs & derivatives
5.
Rev Sci Instrum ; 88(11): 115106, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29195398

ABSTRACT

The improved inflection point method of emissive probe is the most accurate method for plasma potential measurements, but its manual operation is quite cumbersome and time-consuming. This paper describes the design and test of an automatic emissive probe apparatus for efficient plasma potential measurements. The apparatus consists of a computer controlled data acquisition (DAQ) card, a working circuit composed of a biasing unit and a heating unit, as well as the emissive probe. The main feature of the apparatus is that both the biasing scan and the heating scan of the probe are controlled by the computer program through analog outputs of the DAQ card, which easily realizes the required timing between the biasing and heating scans of the probe. The apparatus can automatically execute the improved inflection point method of emissive probe and give the plasma potential result. The advantages of high-accuracy, high-efficiency, and durability of probe filament make the apparatus promising for extensive use in plasma potential measurements.

6.
Fitoterapia ; 121: 106-111, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28625734

ABSTRACT

A series of novel diamide derivatives (2-8) of crocetin (1) were synthesized and evaluated for their cardioprotective activity in vitro. Using well-established model of hypoxia-induced injury in H9c2 cells, we investigated the effects of 9 compounds and positive drug nicorandil on cellular cytotoxicity by MTT assay, mitochondrial viable staining, LDH activity and mitochondrial membrane potential (MMP). Among the new derivatives, compounds 3 and 4 with good liposolubility showed significantly potent activity than crocetin (1) against hypoxia-induced cytotoxicity. Further mechanisms studies indicated that the cardioprotective effect of compounds 3 and 4 was due to these abilities by decreasing LDH release, preserving mitochondrial viabilities and reducing oxidative stress-induced depolarization of MMP. Our results demonstrated that compounds 3 and 4 as a new class of crocetin diamide derivatives could be developed as potential agents in our further drug development studies for ischemic heart disease.


Subject(s)
Carotenoids/pharmacology , Diamide/pharmacology , Myocytes, Cardiac/drug effects , Animals , Carotenoids/chemical synthesis , Cell Hypoxia , Cell Line , Diamide/chemical synthesis , L-Lactate Dehydrogenase/metabolism , Membrane Potential, Mitochondrial/drug effects , Molecular Structure , Oxidative Stress/drug effects , Rats , Vitamin A/analogs & derivatives
7.
Mol Biol Rep ; 41(2): 639-49, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24352702

ABSTRACT

A possible association of glutathione S-transferase T1 (GSTT1) null/presence gene polymorphism and an increased risk of developing gastric carcinoma is still unclear and hotly debated. This investigation was performed to assess the association of the GSTT1 null/presence gene polymorphism with the risk of gastric carcinoma via a meta-analysis to increase sample size and statistical significance. PubMed, Cochrane Library and CBM-disc (China Biological Medicine Database) were searched on March 1, 2013, association reports were identified, and eligible studies were recruited and synthesized. Fifty-two reports were found to be suitable for this meta-analysis for the association of the GSTT1 null genotype with gastric carcinoma risk. The results showed that there was a significantly increased gastric carcinoma risk when the GSTT1 null genotype was present in the overall population (OR 1.21, 95 % CI 1.11-1.32, P < 0.0001), Caucasians (OR 1.25, 95 % CI 1.05-1.48, P = 0.01), East-Asians (OR 1.18, 95 % CI 1.06-1.31, P = 0.003), and Chinese (OR 1.24, 95 % CI 1.07-1.44, P = 0.005). However, no statistically relevant association could be established for the Indian ethnic group (OR 1.33, 95 % CI 0.94-1.90, P = 0.11). In conclusion, the GSTT1 null genotype is associated with an increased gastric carcinoma risk in the overall population, Caucasians, East-Asians, and Chinese.


Subject(s)
Genetic Association Studies , Glutathione Transferase/genetics , Stomach Neoplasms/genetics , Asian People/genetics , Carcinoma , China , Genetic Predisposition to Disease , Genotype , Humans , Polymorphism, Genetic , Risk Factors , Stomach Neoplasms/pathology , White People/genetics
8.
Phys Rev Lett ; 107(5): 055002, 2011 Jul 29.
Article in English | MEDLINE | ID: mdl-21867075

ABSTRACT

We present the experimental evidence of the collisionless electron bounce resonance heating (BRH) in low-pressure dual-frequency capacitively coupled plasmas. In capacitively coupled plasmas at low pressures when the discharge frequency and gap satisfy a certain resonant condition, the high energy beamlike electrons can be generated by fast sheath expansion, and heated by the two sheaths coherently, thus the BRH occurs. By using a combined measurement of a floating double probe and optical emission spectroscopy, we demonstrate the effect of BRH on plasma properties, such as plasma density and light emission, especially in dual-frequency discharges.

9.
Zhonghua Wai Ke Za Zhi ; 45(19): 1311-3, 2007 Oct 01.
Article in Chinese | MEDLINE | ID: mdl-18241562

ABSTRACT

OBJECTIVE: To evaluate the feasibility and practicality of laparoscopic hepatectomy for hepatic hemangioma. METHODS: Candidate for laparoscopic liver resection were 18 cases of hepatic hemangioma from January 2002 to October 2006. The portal bloods stream was blocked by the laparoscope portal blood blocker. The Electric-cautery and ultracision were used for liver transection. Operative procedures included anatomical left hepatectomy in 2 cases, non-anatomical left hepatectomy 1 case, left lobectomy 5 cases, local liver resection 10 cases. Two cases of hepatic hemangioma associated with gallbladder stone were performed cholecystectomy synchronously, 1 case associated with chronic appendicitis were performed appendectomy synchronously. RESULTS: Laparoscopic left liver resection was successfully performed in all 18 cases. The operative duration was (185.4 +/- 55.7) min. The quantity of blood lost during the operation was (416.2 +/- 128.8) ml. The postoperative recovery was smooth and good. No critical complications occurred. The duration for hospitalization was (6.2 +/- 1.0) d. CONCLUSION: Laparoscope hepatectomy for hepatic hemangioma is safe and feasible.


Subject(s)
Hemangioma/surgery , Hepatectomy/methods , Laparoscopy , Liver Neoplasms/surgery , Adult , Feasibility Studies , Female , Humans , Male , Middle Aged , Treatment Outcome
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