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991.
Objective
To investigate the influence of moxibustion products on mitochondrial transmembrane potential (MTP) and mRNA expression of Bax/Bcl-2 in alveolar type II epithelial A549 cells, and to further explore influence of moxibustion products on the oxidative damage of A549 cells.Methods
Smoke and particles generated by moxibustion were collected using the filter box for gas sampling. The moxa smoke extract (MSE) was diluted sequentially to the final concentrations of 0.05 mg/mL, 0.1 mg/mL, 0.2 mg/mL, 0.3 mg/mL and 0.4 mg/mL using the cell culture medium, and A549 cells were then intervened by the above MSE solution. Cell MTP was detected by JC-1 staining. Fluorescence quantitative polymerase chain reaction (PCR) was used to detect Bax/Bcl-2 mRNA expression of A549 cells.Results
Compared with cells in the normal control group, MTP was significantly decreased in cells of 0.3 mg/mL and 0.4 mg/mL MSE intervention groups (P<0.01); while MTP showed no significant changes in cells of 0.05 mg/mL, 0.1 mg/mL and 0.2 mg/mL MSE intervention groups (P>0.05); compared with cells in 0.05 mg/mL MSE intervention group, MTP was decreased significantly in cells of 0.1 mg/mL, 0.2 mg/mL, 0.3 mg/mL and 0.4 mg/mL MSE intervention groups (P<0.05 ); compared with cells in 0.1 mg/mL MSE intervention group, MTP was decreased significantly in cells of 0.4 mg/mL MSE intervention group (P<0.01). Bax mRNA expression of cells in each concentration of MSE intervention group all showed no significant difference compared to that in the normal control group; Bcl-2 mRNA expression of cells was reduced with the increase of MSE intervention concentration. Wherein, Bcl-2 mRNA expressions of cells in 0.4 mg/mL and 0.3 mg/mL MSE intervention groups were significantly reduced compared with that of cells in the normal control group (P<0.05); Bcl-2 mRNA expression of cells in 0.4 mg/mL MSE intervention group was significantly reduced compared to that in 0.05 mg/mL MSE intervention group (P<0.05).Conclusion
Certain higher concentration of moxa smoke could reduce MTP and mRNA expression of the anti-apoptosis gene Bcl-2 in alveolar type II epithelial A549 cells. Oxidative damage may be the important mechanism of apoptosis caused by the high concentration of moxa smoke solution, and further studies are necessary on the specific mechanisms.992.
目的:对比观察脉络膜新生血管(CNV)与息肉状脉络膜血管病变(PCV)在吲哚菁绿血管造影(ICGA)与光学相干断层扫描血管成像(OCTA)中的特征性表现,探讨二者的区别和优缺点。方法:回顾分析2018-09/2020-04在河北省眼科医院确诊的CNV患者26例34眼和PCV患者19例19眼的影像学资料,CNV患者中湿性年龄相关性黄斑变性(w-ARMD)20例28眼,慢性中心性浆液性脉络膜视网膜病变(CCSC)继发CNV 6例6眼。所有患者均行OCTA、荧光素眼底血管造影(FFA)+ICGA检查,分析其特征性改变。结果:w-ARMD患者28眼OCTA检查示,除2眼因出血较多未见明显异常外,余26眼均可显示CNV形态,呈现效果形态更加锐利、立体,且能够分辨出CNV所在的解剖层面,其中11眼OCTA检查不仅能够很好地显示出CNV的形态、大小、范围,而且对于CNV中的滋养血管、新生血管及吻合支也都能较好地分辨。CCSC继发CNV患者6眼OCTA发现了FFA+ICGA未发现的CNV形态。PCV患者19眼OCTA检查异常脉络膜分支血管网(BVN)显示优于ICGA,但OCTA图像上末端囊袋样扩张(p... 相似文献
993.
目的:观察低度近视儿童应用质量分数0.005%阿托品滴眼液控制近视进展的安全性及有效性。方法:前瞻性对照研究。116例116眼低度近视儿童根据受试者和监护人意愿分为两组。阿托品(试验)组:58例58眼近视儿童配戴全矫单焦框架眼镜,同时睡前双眼各点1滴质量分数0.005%的阿托品滴眼液。框架镜(对照)组:58例58眼近视儿童仅配戴全矫单焦框架眼镜。用药前及用药后每4mo复查一次,共随访12mo,观察两组近视等效球镜度、眼轴长度、瞳孔直径和调节幅度的变化情况及试验组的不适症状。结果:随访1a后,两组的近视等效球镜度和眼轴长度治疗前后均有差异(P<0.05);两组间近视等效球镜屈光度增加量无差异(P>0.05);两组间眼轴长度增加量有微小差异,但差异无统计学意义(P>0.05);两组的瞳孔直径增加量有差异(P<0.05);两组的调节幅度下降量有差异(P<0.01)。试验组不适症状:用药初期6眼(10.3%)出现畏光,其中4眼用药2wk后畏光消失,余2眼4wk后消失。无视近模糊、过敏等其它不适症状。结论:低度近视儿童规律应用质量分数0.005%阿托品滴眼液1a,与... 相似文献
994.
目的:探讨四瓣技术在改良结膜囊泪囊鼻腔吻合术中应用的安全性及有效性。方法:回顾性临床研究。选取2017-09/2020-06在我院就诊的泪道疾病患者28例28眼作为研究对象,均行结膜囊泪囊鼻腔吻合术。术后随访6~12mo,观察患者手术效果、满意度及术后并发症情况。结果:本组患者术后荧光素钠染料排泄试验阳性率为96%(27/28),手术成功率为96%(27/28),其中治愈率为68%(19/28),好转率为28%(8/28),无效率为4%(1/28),患者总体满意度为93%(26/28)。术后并发症包括眼部异物感(28眼)、球结膜充血(11眼)、鼻腔结膜囊渗血(8眼)及泪道引流管脱出(1眼)。结论:四瓣技术用于改良结膜囊泪囊鼻腔吻合术手术成功率高,并发症少,安全有效。 相似文献
995.
996.
目的:研究K-115对人Tenon囊成纤维细胞(HTFs)增殖和迁移的影响,并探讨其相关作用机制,为青光眼术后抗瘢痕治疗提供新思路。方法:选取2018-09/2019-09于河北省人民医院行青光眼手术患者的Tenon囊组织,采用组织块法进行HTFs原代培养,应用转化生长因子-β1(TGF-β1)诱导HTFs模拟青光眼滤过性手术后的细胞活化模型,并采用K-115处理细胞。将细胞分为4组:对照组采用溶剂二甲基亚砜(DMSO)处理;TGF-β1组采用10μg/L TGF-β1处理24h; TGF-β1+5 K-115组采用5μmol/L K-115预处理2h后加入10μg/L TGF-β1处理24h; TGF-β1+10 K-115组采用10μmol/L K-115预处理2h后加入10μg/L TGF-β1处理24h。通过细胞增殖实验观察细胞的增殖能力;划痕试验检测细胞的迁移能力;透射电子显微镜观察细胞内自噬小体的形成;Hoechst 33342/PI染色观察细胞凋亡情况。结果:细胞增殖实验结果提示K-115可以抑制TGF-β1诱导的HTFs增殖;划痕试验提示K-115可以抑制TGF-β1诱... 相似文献
997.
998.
Li Yingxian Chen Wei Zhao Linchun Zhang Ji-Quan Zhao Yonglong Li Chun Guo Bing Tang Lei Yang Yuan-Yong 《RSC advances》2022,12(32):20550
Amide is a fundamental group that is present in molecular structures of all domains of organic chemistry and the construction of this motif with high atom economy is the focus of the current research. Specifically, N-methyl amides are valuable building blocks in natural products and pharmaceutical science. Due to the volatile nature of methyl amine, the generation of N-methyl amides using simple acids with high atom economy is rare. Herein, we disclose an atom economic protocol to prepare this valuable motif under DABCO/Fe3O4 cooperative catalysis. This protocol is operationally simple and compatible with a range of aliphatic and (hetero)aromatic acids with very good yields (60–99%). Moreover, the Fe3O4 can be easily recovered and high efficiency is maintained for up to ten cycles.The generation of N-methyl amides using simple acids with high atom economy is rare owning to the volatile nature of methyl amine. Herein, an atom economic protocol was disclosed to prepare this valuable motif under DABCO/Fe3O4 cooperative catalysis.Amide is a fundamental group that is present in molecular structures of all domains of organic chemistry.1 It is widely distributed in natural products, synthetic drugs and functional polymers, and is also the key chemical connection in proteins.2 It has been shown that amide bond formation alone accounts for 65% of all preliminary screening reactions in the pharmaceutical industry.3 This means the generation of amide bonds with high atom efficiency is of high practical importance. And not surprisingly, ‘amide formation avoiding poor atom economy reagents’ was voted as the top challenge for organic chemistry by the ACS Green Chemistry Institute in 2007.3From synthetic point of view, the ideal way to produce amide bonds would be the direct coupling of readily available carboxylic acids and amines, but this process is thermodynamically unfavourable due to the formation of the corresponding carboxylate-ammonium salt,4 therefore, stoichiometric amount of coupling reagents, such as DCC, DIC, EDCI, HATU, HBTU, HCTU, SOCl2, BOP, acid chloride etc, are generally required to sidestep thermal conditions for amide bond formation.5 These reagents are highly successful, but the process generally suffers from poor atom economy and side products removal issue especially in the large-scale applications.5 To overcome these drawbacks, “nonclassical” amide bonds formation routes were investigated.6 In these processes, the catalyst takes the role of a coupling reagent in generating an active ester suitable for amidation in a waste-free manner. However, these processes have not been applied in the preparation of N-methyl amides, probably because the methyl amine was delivered in its hydrochloride salt, alcoholic or aqueous form due to its volatile nature.On a different note, N-methyl amides are extensively presented in numerous natural products and pharmaceutical molecules, as shown in Fig. 1,7 and the methylation of amides is a promising way to improve the pharmacological property of molecules.8 However, the synthesis of N-methyl amides compounds relies heavily on non-catalytic approaches.5,9 Catalytic approaches were also investigated by Hisaeda,10 Kundu,11 Li,12 Guo,13 Yu,14 Maruoka,15 Wang,16 Chen,17 Lamaty18 and their co-workers starting from nitriles, primiary amides, aldoximes, aldehydes, lignin, carbamoylsilane and alcohols. Until recently, Thakur,19 Marce,20 Sadeghzadeh21 and their co-workers developed elegant N-methyl amidation approach starting from carboxylic acids under nano-MgO, diatomite Earth@IL/ZrCl4 and Mg(NO3)2·6H2O catalysis respectively, while limitations like poor substrate scope or sophisticated tailored catalyst still persist. Mindful of all the above issues, developing an N-methyl amidation process of simple carboxylic acids, which is still of great challenge in synthesis, and establishing a broad (hetero)aryl scope with high atom economy from commercial available reagents and catalysts were critical considerations in this study. Moreover, the significance of N-methyl amides combined with our interests in the development of green synthetic approaches motivated us to explore the direct coupling of the carboxylic acids and isothiocyanates. To the best of our knowledge, this is the first successful work using isothiocyanatomethane to prepare N-methyl amides.Open in a separate windowFig. 1Marketed drugs bearing N-methyl amide group.Our initial investigation begins with phenylacetic acid and isothiocyanatomethane as model substrate for condition optimization. Using acetonitrile as solvent, only trace amount of product was detected under catalyst free or p-toluenesulfonic acid (PTSA) catalysis conditions ( Entry Additive Time (h) Catalyst Yield (%) 1 — 24 — 5 2 — 24 PTSA — 3 — 48 TEA 17 4 — 48 DBU 45 5 — 48 DMAP 43 6 — 48 DBN 51 7 — 48 DABCO 65 8 LiBr 48 DABCO 71 9 Mn(OAc)2 48 DABCO 75 10 MnO 48 DABCO 79 11 MgO 48 DABCO 88 12 Al2O3 48 DABCO 85 13 Fe3O4 48 DABCO 98 14 Fe3O4 24 DABCO 75 15b Fe3O4 48 DABCO 80