Effect of iron overload on electrophysiology of slow reaction autorhythmic cells of left ventricular outflow tract in guinea pigs

Objective: To investigate the electrophysiology effects and mechanism of iron overload on the slow response autorhythmic cells in the left ventricular outflow tract of guinea pigs.Methods: Standard microelectrode cell recording techniques were adopted to observe the electrophysiological effects of different concentrations of Fe^(2+)(100 μmol/L, 200 μmol/L) on the left ventricular outflow tract autorhythmic cells.Heart tissues were perfused with FeSO_4(200 μmol/L) combing with CaCl_2(4.2 mmol/L), Verapamil,(1 μmol/L), and nickel chloride(200μmol/L) respectively to observe the influences of these contents on electrophysiology of FeSO_4(200μmol/L) on the left ventricular outflow tract autorhythmic cells.Results: Fe^(2+)at both 100 μmol/L and 200 μmol/L could change the electrophysiological parameters of the slow response autorhythmic cells of the left ventricular outflow tract in a concentrationdependent manner resulting into decrease in Vmax, APA and MDP, slower RPF and VDD, and prolonged APD_(50) and APD_(90)(P all <0.05).Besides, perfusion of increased Ca^(2+) concentration could partially offset the electrophysiological effects of Fe^(2+)(200 μmol/L).The L-type calcium channel(LTCC) blocker Verapamil(1 μmol/L) could block the electrophysiological effects of Fe^(2+)(200 μmol/L).But the T-type calcium channel(TTCC) blocker nickel chloride(NiCl_2, 200 μmol/L) could not block the electrophysiological effects of Fe^(2+)(200 μmol/L).Conclusions: Fe^(2+) can directly change the electrophysiological characteristics of the slow response autorhythmic cells of the left ventricular outflow tract probably through the L-type calcium channel.

Perinodular ductular reaction/epithelial cell adhesion molecule loss in small hepatic nodules

AIM: To investigate if loss of epithelial cell adhesion molecule (EpCAM) is associated with microinvasion in hepatocellular carcinomas (HCCs) in the presence of chronic hepatitis B.

Combination of a reaction cell and an ultra-high vacuum system for the in situ preparation and characterization of a model catalyst

An in-depth understanding of the structure-activity relationship between the surface structure,chemical composition,adsorption and desorption of molecules,and their reaction activity and selectivity is necessary for the rational design of high-performance catalysts.Herein,we present a method for studying catalytic mechanisms using a combination of in situ reaction cells and surface science techniques.The proposed system consists of four parts:preparation chamber,temperatureprogrammed desorption(TPD)chamber,quick load-lock chamber,and in situ reaction cell.The preparation chamber was equipped with setups based on the surface science techniques used for standard sample preparation and characterization,including an Ar+sputter gun,Auger electron spectrometer,and a low-energy electron diffractometer.After a well-defined model catalyst was prepared,the sample was transferred to a TPD chamber to investigate the adsorption and desorption of the probe molecule,or to the reaction cell,to measure the catalytic activity.A thermal desorption experiment for methanol on a clean Cu(111)surface was conducted to demonstrate the functionality of the preparation and TPD chambers.Moreover,the repeatability of the in situ reaction cell experiment was verified by CO_(2) hydrogenation on the Ni(110)surface.At a reaction pressure of 800 Torr at 673 K,turnover frequencies for the methanation reaction and reverse water-gas shift reaction were 0.15 and 7.55 Ni atom^(-1) s^(-1),respectively.

Recent developments in electrocatalysts and future prospects for oxygen reduction reaction in polymer electrolyte membrane fuel cells

The main difficulty in the extensive commercial use of polymer electrolyte membrane fuel cells （PEMFCs） is the use of noble metals such as Pt-based electrocatalyst at the cathode, which is essential to ease the oxygen reduction reaction （ORR） in fuel cells （FCs）. To eliminate the high loading of Pt-based electrocatalysts to minimize the cost, extensive study has been carried out over the previous decades on the non-noble metal catalysts. Development in enhancing the ORR performance of FCs is mainly due to the doped carbon materials, Fe and Co-based electrocatalysts, these materials could be considered as probable substitutes for Pt-based catalysts. But the stability of these non-noble metal electrocatalysts is low and the durability of these metals remains unclear. The three basic reasons of instability are： （i） oxidative occurrence by H2O2, （ii） leakage of the metal site and （iii） protonation by probable anion adsorption of the active site. Whereas leakage of the metal site has been almost solved, more work is required to understand and avoid losses from oxidative attack and protonation. The ORR performance such as stability tests are usually run at low current densities and the lifetime is much shorter than desired need. Therefore, improvement in the ORR activity and stability afe the key issues of the non-noble metal electrocatalyst. Based on the consequences obtained in this area, numerous future research directions are projected and discussed in this paper. Hence, this review is focused on improvement of stability and durability of the non-noble metal electrocatalyst.

Influence of Dry Methane Reactions on the Cell Output Characteristics of Solid Oxide Fuel Cells

In order to study the influence of dry methane concentration on outputs in solid oxide fuel cells (SOFCs), the output performance was obtained for dry methane of different concentrations on a Ni-ScSZ anode in solid oxide fuel cells, and the anode exhaust gas was measured by online chromatography. The underlying causes of the output performance change were analyzed from the anode reactions by summarizing the anode exhaust gas regular pattern for different reactions, and analyzing the electrochemical reaction kinetics of methane with oxygen ion. As the oxygen ion concentration at the anode three-phase boundary proportionally increased with current density, the following reactions occurred for different dry methane concentrations in sequence CH4 + O2﹣ → CO + 2H2 + 2e﹣, CH4 + 2O2﹣ → CO + H2O + H2 + 4e﹣, CH4 + 3O2﹣ → CO + 2H2O + 6e﹣, CH4 + 4O2﹣ → CO2 + 2H2O + 8e﹣. With various concentrations of methane at a low current, the outlet methane continuously reduced with the increase of the current density. Meanwhile, CO and H2 exhaust gas increased with increasing current density for low concentration of methane. With methane concentrations at 3.85% and 5.66%, the cell output voltage dropped rapidly. For concentrations of 29.7% and 3.85%, the anode exhaust residual methane changed irregularly with current density and this phenomenon was associated with the dry methane that reacted on anode of the cell. The transformation of reactions, the water produced in the electrochemical reactions and the polarization in response to the change of reactions maybe induced the output voltage and power density reducing as low concentrations of dry methane were used.

Lignin derived multi-doped(N, S, Cl) carbon materials as excellent electrocatalyst for oxygen reduction reaction in proton exchange membrane fuel cells

Nowadays,hierarchically macro-/meso-/microporous 3D carbon materials have been paid more attention due to their imaginative application potential in specific electrochemistry.Here,we report a dualtemplate strategy using eutectic NaCl/ZnCl2 melt as airtight and swelling agent to obtain 3D mesoporous skeleton structured carbon from renewable lignin.The prepared lignin-derived biocarbon material(LN-3-1)has a high specific surface area(1289 m^2 g^-1),a large pore volume(2.80 cm^3 g^-1),and a well-connected and stable structure.LN-3-1 exhibits extremely high activity and stability in acidic medium for oxygen reduction reaction(ORR),superior to Pt/C catalyst and most non noble-metal catalysts reported in recent literatures.The prepared carbon material was used as a cathode catalyst to assemble a H2-O2 single fuel cell,and its excellent catalytic performance has been confirmed with the maximum power density of 779 mW cm^-2,which is one of the highest power densities among non-metallic catalysts so far.Density functional theory(DFT)calculations indicate that the synergy of chlorine and nitrogen reconciles the intermediate adsorption energies,leading to an appropriate theoretical ORR onset potential.We develop a cost-effective and highly efficient method to prepare biocarbon catalyst for ORR in proton-exchange membrane fuel cells.

Chemical reaction model of cathode failure in large prebaked anode aluminum reduction cells

By partial and general dissection of large prebaked alumina electrolysis cells, the macro appearance, chemical composition and phase variations were studied employing actual observations and measurements on the cells together with X ray diffraction phase analysis and scanning electron microscopy of samples from different locations. According to the practical production, a chemical reaction model of aluminum reduction cell failure was set up in order to reduce the incidence of cell failure and extend pot service life.

Treatment of Skin Reaction Induced by Nivolumab Combined with Radiotherapy in Non-small Cell Lung Cancer:A Case Report

Skin reaction or dermatological toxicities induced by immunotherapy is common.It usually manifests skin rash or erythema and can be cured by skin lotion or steroid.Nivolumab,a human IgG4 programmed cell death protein 1(PD-1)inhibitor,blocks T cells activation preventing signal and allows the immune system to clear cancer cells.Nivolumab was approved in the second-line therapy in squamous cell lung cancer by FDA,with less than 10%unusual skin reaction,like sensory neuropathy,peeling skin,erythema multiforme,vitiligo,and psoriasis.Radiotherapy could aggravate this skin reaction through inflammatory response and promotion of immunity.The combined treatment of anti-PD-1 and radiotherapy represented a new promising therapeutic approach in many studies,but the risk of side effects may be high.We reported a patient with advanced squamous cell lung cancer who suffered from serious skin immune-related adverse events when he was treated with nivolumab and radiotherapy.The immune overreaction of the treatment of anti-PD-1 treatment and radiotherapy might cause these serious skin adverse events.Our report warranted careful workup to reduce the risk of side effects by combinative therapy with anti-PD-1 and radiotherapy.

CHRONOABSORPTOMETRY FOR THE DETERMINATION OF KINETIC PARAMETERS OF ELECTRON TRANSFER REACTIONS USING LONG-OPTICAL-PATH ELECTROCHEMICAL CELL

A single potential step chronoabsorptometric method for the determination of ki- netic parameters of simple quasi-reversible reactions is described.It is verified by determining the kinetic parameters for the electroreduction of ferricyanide.A long-optical-path electro- chemical cell with a plug-in electrode is used.The thickness of solution layer is 0.55 mm

Application of donor dendric cell mediated recipieut lymphocyte reaction after related kidney transplantation in individualized immunosuppressive therapy

Objective To explore the feasibility of mediating recipient lymphocyte reaction with donor dendritic cells ( Dcs) in renal allograft recipients to guide individualized immunosuppressive therapy. Methods From Jan. 2008 to Jan. 2010,30 recipients received living related kidney transplantation were successively and divided into

Paraneoplastic leukemoid reaction in a patient with sarcomatoid hepatocellular carcinoma: A case report

BACKGROUND Sarcomatoid hepatocellular carcinoma (SHC) combined with paraneoplastic leukemoid reaction (PLR), which is associated with a poor prognosis, is rarely seen in the clinic. Here, we report the case of a patient in the above situation. CASE SUMMARY A 75-year-old female patient with a past medical history of hypertension and cerebral infarction paid a hospital visit as a result of right upper quadrant abdominal pain and anorexia for two months. Laboratory examination revealed a white blood cell (WBC) count of 43790/μL, which was then increased up to 77050/μL. In addition, the results of bone marrow examination suggested a leukemoid reaction. Computed tomography (CT) revealed a focal hepatic mass, which was confirmed through pathological examination to be an SHC postoperatively. In addition, the WBC count had fallen to a normal level before she left the hospital. However, the patient died two and a half months after the second hospital admission. CONCLUSION This is a rare case of SHC combined with PLR, both of which have an extremely poor prognosis.

人免疫球蛋白联合阿昔洛韦治疗病毒性脑炎患者的效果

目的:观察人免疫球蛋白联合阿昔洛韦治疗病毒性脑炎(VE)患者的效果。方法:回顾性分析2021—2023年该院收治的78例VE患者的临床资料,按照治疗方法不同将其分为对照组和研究组各39例。两组均予以基础治疗,在此基础上,对照组予以阿昔洛韦治疗,研究组在对照组基础上联合人免疫球蛋白治疗,两组均持续治疗10 d。比较两组临床疗效,症状消失时间,治疗前后脑脊液炎性因子[白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、降钙素原(PCT)]水平、T细胞亚群指标(CD3^(+)、CD4^(+)、CD8^(+))水平,以及不良反应发生率。结果:研究组治疗总有效率为94.87%(37/39),高于对照组的76.92%(30/39),差异有统计学意义(P<0.05);研究组头痛、呕吐、抽搐、精神行为异常等症状消失时间均短于对照组,差异有统计学意义(P<0.05);治疗后,研究组脑脊液IL-6、TNF-α、PCT水平均低于对照组,差异有统计学意义(P<0.05);治疗后,研究组CD3^(+)、CD4^(+)水平高于对照组,CD8^(+)水平低于对照组,差异均有统计学意义(P<0.05);两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:人免疫球蛋白联合阿昔洛韦治疗VE患者可提高治疗总有效率,缩短症状消失时间,降低脑脊液炎性因子水平,改善T细胞亚群指标水平,效果优于单纯阿昔洛韦治疗。

Detection of hepatocellular carcinoma cells in the peripheral blood with reverse--transcription polymerase chain reaction

In order to detect circulating cells of hepatocellular carcinoma(HCC) in the peripheral blood with reverse transcripition polymerase chain reaction (RT-PCR ), alpha-fetoprotein (AFP ) mRNA was tested in the blood samples of 113 cases of HCC and 69 controls (including 30 cases of liver cirrhosis, 9 cases of metastatic liver cancer and 30 normal subjects). 20/43 (46. 5% ) cases of HCC and 2/30 (6. 7% ) cases of liver cirrhosis are positive and the cases of nletastatic liver cancer and normal controls were negative for human AFP(hAFP) rnRNA. The presence of hAFP mRNA in the peripheral blood seems to be correlated with intrahepatic and distant nletastasls of HCC and portal vein thrombosis. It is concluded that the presence of hAFP mRNA in the peripheral hloocl is an indicator of circulating HCC cells and can be used to diagnose the rnetastasisof HCC through henlatogenous route and RT-PCR amplification of hAFP mRNA is a sensitive and specificprocedure for detecting circulating cells of HCC.

罗汉果苷V调控高糖状态巨噬细胞M1极化促进骨髓间充质干细胞的成骨分化

背景:糖尿病微环境会造成巨噬细胞过度M1极化,这种高糖炎症状态会抑制骨髓间充质干细胞的成骨分化,从而影响糖尿病骨缺损的愈合。研究表明罗汉果苷Ⅴ具有抗炎、抗氧化、降血糖的作用,但其能否调节高糖炎症状态下巨噬细胞M1极化及骨髓间充质干细胞的成骨分化尚不清楚。目的:探讨罗汉果苷Ⅴ在高糖炎症状态下调节巨噬细胞M1型极化对骨髓间充质干细胞成骨分化的影响。方法:构建糖尿病C57BL/6小鼠模型,从正常和糖尿病小鼠分离骨髓来源巨噬细胞,分别培养于低糖和高糖培养基。使用脂多糖和干扰素γ作为炎症刺激诱导骨髓来源巨噬细胞的M1型极化,同时以160,320,640μmol/L罗汉果苷Ⅴ干预,用流式细胞术检测F4/80^(+)CD86^(+)细胞比例,qRT-PCR检测诱导型一氧化氮合酶、白细胞介素1β、白细胞介素6的mRNA表达水平,ELISA检测骨髓来源巨噬细胞上清液中肿瘤坏死因子α水平。分离C57BL/6小鼠骨髓间充质干细胞,分别使用低糖或高糖成骨诱导液诱导成骨分化,添加M1型巨噬细胞条件培养基作为炎症刺激,以及320μmol/L罗汉果苷Ⅴ干预,成骨诱导14 d后采用qRT-PCR检测碱性磷酸酶、Runt相关因子2、骨钙素、骨桥蛋白的mRNA表达水平,成骨诱导21 d后进行茜素红染色及定量分析。结果与结论:①流式细胞术结果显示320,640μmol/L罗汉果苷Ⅴ组的F4/80^(+)CD86^(+)细胞比例明显低于高糖炎症对照组(P<0.05);②qRT-PCR结果显示160,320,640μmol/L罗汉果苷Ⅴ组的诱导型一氧化氮合酶、白细胞介素6的mRNA相对表达量较高糖炎症对照组显著降低(P<0.05),320,640μmol/L罗汉果苷Ⅴ组白细胞介素1β的mRNA相对表达量较高糖炎症对照组显著降低(P<0.05);③ELISA结果显示160,320,640μmol/L罗汉果苷Ⅴ组的肿瘤坏死因子α分泌水平较高糖炎症对照组显著降低(P<0.05);④320μmol/L罗汉果苷Ⅴ干预后,高糖炎症状态下骨髓间充质干细胞的钙盐沉积增加(P<0.05),且碱性磷酸酶、Runt相关因子2和骨桥蛋白的mRNA相对表达量增加(P<0.05)。结果表明,罗汉果苷Ⅴ可通过抑制高糖炎症状态下骨髓来源巨噬细胞的M1型极化及炎症因子表达,促进骨髓间充质干细胞的成骨分化。

甲烷混合燃料气内重整反应对平板式固体氧化物燃料电池性能影响

为研究经过预重整的含甲烷混合燃料气中甲烷浓度及内部重整对平板式固体氧化物燃料电池电化学性能和热机械性能的影响,建立甲烷内重整平板式固体氧化物燃料电池模型,并对多孔材料的弹性模量及泊松比进行修正,对比3种不同甲烷浓度条件下电池的综合性能。结果表明:在电化学性能方面,随着混合燃料气中甲烷浓度的增大,电池电流密度和功率密度逐渐增大,流道中甲烷的摩尔浓度沿燃料流动方向逐渐减小,氢气浓度沿流动方向呈先增大后减小的趋势,氢气的最大浓度逐渐远离燃料入口;热机械性能方面,随着混合燃料气中甲烷浓度的增大,位于金属连接体上的电池最大第一主应力和位于燃料出口的电池最大温度逐渐降低。适当提高混合燃料气中甲烷的浓度有利于平板式固体氧化物燃料电池的综合性能优化。

物质输运定量反馈实现PEMFC阴极流道非均匀设计

流道非均匀设计是改善质子交换膜燃料电池(PEMFC)内部物理场不均匀分布的最主要方式之一。已有研究设计思路主要是基于对PEMFC工作原理的定性理解确定设计方向,再在此设计方向上进行参数优化,而未能把所得结果反馈用于修正设计思路。对此提出了一种结果反馈再寻优的设计思路,首先对PEMFC结构参数进行参数分析,再对计算结果中物质输运过程进行定量分析,从而反馈确定结构设计方向。采用上述思路对单通道PEMFC流道宽度、单电池子流道高度进行了非均匀设计。结果表明:相比于对照组,采用非均匀设计的PEMFC净功率密度提升幅度为4%~6%,且PEMFC内物理场分布均匀性较好。该研究能够指导PEMFC流道结构不均匀设计方向,助力高性能、长寿命PEMFC设计。

Detection of Mycoplasma Contamination in Animal Cell Cultures

[ Objective ] To develop a rapid efficient method for detecting mycoplasma contamination in cell cultures. [ Method] A pair of primers was designed according to two highly conserved nucleotide sequences of the 16S RNA from six kinds of mycoplasma that commonly contaminated cells. Then the mycoplasma contamination of 25 cell samples was defected by PCR and DNA fluorescence staining. EResultl When these cell samples were detected by DNA fluorescence staining, the positive rate and probable positive rate were respectively 24% and 16%. And when they were detected by PCR, the positive rate was 36%. [ Condusion] The PCR method is more sensitive and specific than the DNA fluorescence staining, and combining these two methods is the optimal way to detect mycoplasma contamination in cell cultures.

复方α-酮酸联合血液透析治疗肾衰竭患者的效果

目的:观察复方α-酮酸联合血液透析治疗肾衰竭患者的效果。方法:回顾性分析2021年5月至2023年2月该院收治的118例肾衰竭患者的临床资料,根据治疗方法不同将其分为对照组和研究组各59例。对照组采用血液透析治疗,研究组在对照组基础上联合复方α-酮酸治疗,比较两组治疗前及治疗3、6个月后钙磷代谢指标[血磷、血钙、全段甲状旁腺激素(iPTH)]、T细胞亚群指标(CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+))、血清学指标[β2-微球蛋白(β2-MG)、成纤维细胞生长因子(FGF)-23、结缔组织生长因子(CTGF)]水平,以及不良反应发生率。结果:治疗3、6个月后,两组血钙水平均高于治疗前,且研究组高于对照组,两组血磷、iPTH水平均低于治疗前,且研究组低于对照组,差异有统计学意义(P<0.05);两组CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+)水平均高于治疗前,且研究组高于对照组,差异有统计学意义(P<0.05);两组β2-MG、FGF-23、CTGF水平均低于治疗前,且研究组低于对照组,差异有统计学意义(P<0.05);两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:复方α-酮酸联合血液透析治疗肾衰竭患者可提高T细胞亚群指标水平,改善钙磷代谢指标水平,以及降低血清学指标水平的效果优于单纯血液透析治疗。

帕拉米韦与奥司他韦治疗流行性感冒患儿的效果比较

目的:比较帕拉米韦与奥司他韦治疗流行性感冒(简称流感)患儿的效果。方法:回顾性分析2022年6月至2023年6月该院收治的88例流感患儿的临床资料,按照治疗方法不同将其分为对照组和观察组各44例。两组均给予常规治疗,在此基础上,对照组给予奥司他韦治疗,观察组给予帕拉米韦治疗。比较两组临床症状(发热、咳嗽、流涕、咽喉肿痛、关节酸痛)持续时间,治疗前后炎性因子[肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)、C反应蛋白(CRP)]、T细胞亚群指标(CD3^(+)、CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+))水平,以及不良反应发生率。结果:观察组发热、咳嗽、流涕、咽喉肿痛、关节酸痛等临床症状持续时间均短于对照组,差异有统计学意义(P<0.05);治疗后,观察组TNF-α、IL-6、CRP水平均低于对照组,差异有统计学意义(P<0.05);治疗后,观察组CD3^(+)、CD4^(+)、CD4^(+)/CD8^(+)水平高于对照组,CD8^(+)水平低于对照组,差异均有统计学意义(P<0.05);两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:帕拉米韦治疗流感患儿可缩短临床症状持续时间,降低炎性因子水平,改善T细胞亚群指标水平,效果优于奥司他韦治疗。

Bio-inspired carbon electro-catalysts for the oxygen reduction reaction

We report the synthesis, characterisation and catalytic performance of two nature-inspired biomassderived electro-catalysts for the oxygen reduction reaction in fuel cells. The catalysts were prepared via pyrolysis of a real food waste（lobster shells） or by mimicking the composition of lobster shells using chitin and CaCO3 particles followed by acid washing. The simplified model of artificial lobster was prepared for better reproducibility. The calcium carbonate in both samples acts as a pore agent, creating increased surface area and pore volume, though considerably higher in artificial lobster samples due to the better homogeneity of the components. Various characterisation techniques revealed the presence of a considerable amount of hydroxyapatite left in the real lobster samples after acid washing and a low content of carbon（23%）, nitrogen and sulphur（〈1%）, limiting the surface area to 23 m^2/g, and consequently resulting in rather poor catalytic activity. However, artificial lobster samples, with a surface area of ≈200 m^2/g and a nitrogen doping of 2%, showed a promising onset potential, very similar to a commercially available platinum catalyst, with better methanol tolerance, though with lower stability in long time testing over 10,000 s.