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141.
Jing Guo Ying Xie Qiao-Lei Wu Wen-Tian Zeng Albert S. C. Chan Jiang Weng Gui Lu 《RSC advances》2018,8(29):16202
An aerobic decarboxylative cross-coupling of α-amino acids with diverse C–H nucleophiles has been realized using Cu2(OH)2CO3 (1 mol%) as the catalyst under air. This protocol enables highly efficient formation of various C(sp3)–C(sp3), C(sp3)–C(sp2) and C(sp3)–C(sp) bonds under simple conditions without the use of any ligand or extra oxidant, providing a practical approach to numerous nitrogen-containing compounds in good to excellent yields. The efficiency and practicability were also demonstrated by the gram-scale experiment and three-step synthesis of a Rad51 inhibitor.An aerobic decarboxylative cross-coupling of α-amino acids was realized using 1 mol% Cu2(OH)2CO3 catalyst under ligand free conditions. 相似文献
142.
Yi-Nan Ding Ming Xue Qiu-Sha Tang Li-Jun Wang Hui-Yan Ding Han Li Cheng-Cheng Gao Wei-Ping Yu 《World journal of gastroenterology : WJG》2022,28(37):5403-5419
Gastrointestinal cancer (GIC) is the most common cancer with a poor prognosis. Currently, surgery is the main treatment for GIC. However, the high rate of postoperative recurrence leads to a low five-year survival rate. In recent years, immunotherapy has received much attention. As the only immunotherapy drugs approved by the Food and Drug Administration (FDA), immune checkpoint blockade (ICB) drugs have great potential in cancer therapy. Nevertheless, the efficacy of ICB treatment is greatly limited by the low immunogenicity and immunosuppressive microenvironment of GIC. Therefore, the targets of immunotherapy have expanded from ICB to increasing tumor immunogenicity, increasing the recruitment and maturation of immune cells and reducing the proportion of inhibitory immune cells, such as M2-like macrophages, regulatory T cells and myeloid-derived suppressor cells. Moreover, with the development of nanotechnology, a variety of nanoparticles have been approved by the FDA for clinical therapy, so novel nanodrug delivery systems have become a research focus for anticancer therapy. In this review, we summarize recent advances in the appli cation of immunotherapy-based nanoparticles in GICs, such as gastric cancer, hepatocellular carcinoma, colorectal cancer and pancreatic cancer, and described the existing challenges and future trends. 相似文献
143.
Shang-Qing Huang Yi Wen Hong-Yu Sun Jie Deng Yao-Lei Zhang Qi-Lin Huang Bing Wang Zhu-Lin Luo Li-Jun Tang 《World journal of gastroenterology : WJG》2021,27(9):815-834
BACKGROUND Our previous studies confirmed that abdominal paracentesis drainage(APD)attenuates intestinal mucosal injury in rats with severe acute pancreatitis(SAP),and improves administration of enteral nutrition in patients with acute pancreatitis(AP).However,the underlying mechanisms of the beneficial effects of APD remain poorly understood.AIM To evaluate the effect of APD on intestinal inflammation and accompanying apoptosis induced by SAP in rats,and its potential mechanisms.METHODS SAP was induced in male adult Sprague-Dawley rats by 5%sodium taurocholate.Mild AP was induced by intraperitoneal injections of cerulein(20μg/kg body weight,six consecutive injections).Following SAP induction,a drainage tube connected to a vacuum ball was placed into the lower right abdomen of the rats to build APD.Morphological changes,serum inflammatory mediators,serum and ascites high mobility group box protein 1(HMGB1),intestinal barrier function indices,apoptosis and associated proteins,and toll-like receptor 4(TLR4)signaling molecules in intestinal tissue were assessed.RESULTS APD significantly alleviated intestinal mucosal injury induced by SAP,as demonstrated by decreased pathological scores,serum levels of D-lactate,diamine oxidase and endotoxin.APD reduced intestinal inflammation and accompanying apoptosis of mucosal cells,and normalized the expression of apoptosis-associated proteins in intestinal tissues.APD significantly suppressed activation of the intestinal TLR4 signaling pathway mediated by HMGB1,thus exerting protective effects against SAP-associated intestinal injury.CONCLUSION APD improved intestinal barrier function,intestinal inflammatory response and accompanying mucosal cell apoptosis in SAP rats.The beneficial effects are potentially due to inhibition of HMGB1-mediated TLR4 signaling. 相似文献
144.
145.
Li H Groop L Nilsson A Weng J Tuomi T 《The Journal of clinical endocrinology and metabolism》2003,88(6):2767-2774
Our previous results have suggested that genes outside the human leukocyte antigen (HLA) class II locus may affect the phenotype of type 2 diabetic patients from families with both type 1 and type 2 diabetes (mixed type 1/2). To study whether the TNF alpha gene could be such a modifying gene, we studied TNF alpha promoter polymorphisms (G-->A substitution at positions -308 and -238) in relation to HLA-DQB1 genotypes in type 2 patients from mixed type 1/2 families or common type 2 diabetes families as well as in patients with adult-onset type 1 diabetes and control subjects. The TNF alpha(308) AA/AG genotype frequency was increased in adult onset type 1 patients (55%, 69 of 126), but it was similar in type 2 patients from type 1/2 families (35%, 33/93) or common type 2 families (31%, 122 of 395), compared with controls (33%, 95/284; P < 0.0001 vs. type 1). The TNF alpha(308) A and DQB1*02 alleles were in linkage disequilibrium in type 1 patients (Ds = 0.81; P < 0.001 vs. Ds = 0.25 in controls) and type 2 patients from type 1/2 families (Ds = 0.59, P < 0.05 vs. controls) but not in common type 2 patients (Ds = 0.39). The polymorphism was associated with an insulin-deficient phenotype in the type 2 patients from type 1/2 families only together with DQB*02, whereas the common type 2 patients with AA/AG had lower waist to hip ratio [0.92 (0.12) vs. 0.94 (0.11), P = 0.008] and lower fasting C-peptide concentration [0.48 (0.47) vs. 0.62 (0.46) nmol/liter, P = 0.020] than those with GG, independently of the presence of DQB1*02. In conclusion, TNF alpha is unlikely to be the second gene in the HLA area responsible for our previous findings in type 1/2 patients. However, we could show an association between TNF alpha(308) polymorphism and the phenotype of common type 2 diabetes. 相似文献
146.
Effects of medroxyprogesterone and estradiol on the recovery of spermatogenesis in irradiated rats 总被引:1,自引:0,他引:1
Shetty G Weng CC Bolden-Tiller OU Huhtaniemi I Handelsman DJ Meistrich ML 《Endocrinology》2004,145(10):4461-4469
Suppression of intratesticular testosterone (ITT) levels is required for spermatogenic recovery in rats after irradiation, but maintenance of peripheral testosterone (T) levels is important for many male functions. Considering the preservation of peripheral T while suppressing ITT, we tested the effects of a combination of a progestin, medroxyprogesterone acetate (MPA), plus T on spermatogenic recovery after irradiation, and compared its effects to those of T alone or T combined with estradiol (E2). Rats were given testicular irradiation (6 Gy) and treated during wk 3-7 after irradiation with MPA + T, or the individual steroids with or without GnRH antagonist (GnRH-ant), or GnRH-ant alone, or T + E2. Whereas GnRH-ant alone stimulated differentiation in 55% of tubules 13 wk after irradiation compared with 0% in irradiated-only rats, the addition of MPA reduced the percentage of tubules showing differentiation to 18%. However, T or MPA alone or the combination of the two induced germ cell differentiation in only 2-4% of tubules. In contrast, E2 stimulated differentiation in 88% of tubules, and T combined with E2 still resulted in differentiation in 30% of tubules. Although both MPA and E2 suppressed ITT levels to approximately 2% of control (2 ng/g testis), MPA was a less effective stimulator of spermatogenic recovery than E2 or GnRH-ant alone. MPA's function as a weak androgen was likely responsible for inhibiting spermatogenic recovery, as was the case for all other tested androgens. Thus, for clinical protection or restoration of spermatogenesis after radiation or chemotherapy by suppressing T production, MPA, at least in the doses used in the present study, is suboptimal. The combination of an estrogen with T appears to be most effective for stimulating such recovery. 相似文献
147.
Xin-Da Zhou Zhao-You Tang Ye-Qin Yu Jian-Mao Weng Zeng-Chen Ma Bo-Heng Zhang Ya-Xin Zheng 《Journal of cancer research and clinical oncology》1993,120(1-2):100-102
From November 1973 to June 1992, cryosurgery with liquid nitrogen (–196°C) was performed on 113 patients with hepatic cancer, including 107 patients with primary liver cancer (PLC) and 6 patients with secondary liver cancer (SLC). Of the 107 PLC patients, the subclinical stage constituted 30.8% (33/107), the moderate stage 61.7% (66/107), and the late stage 7.5% (8/107). There were 32 cases with small PLC (up to 5 cm). Liver cirrhosis was observed in 86.0% (92/107). We designed flat cryoprobes for freezing surface tumors, and single and multiple trocar cryoprobes for freezing tumors deep within the hepatic parenchyma. Intraoperative ultrasound was used for monitoring hepatic cryolesions. There were no operative mortalities and complications, such as rupture of a tumor, delayed bleeding, or bile leakage. The 5-year and 10-year survival rates were 22.0% and 8.2%, respectively, for the 107 PLC patients and 48.8% and 17.1%, respectively, for the 32 patients with small PLC. Of the 6 SLC patients, survival ranged from 2 months to 90 months (average, 23.2 months). One SLC patient has been well for 7 years and 6 months after cryosurgery. These results indicate that cryosurgery, the in situ freezing of cancer, is a safe and effective treatment for unresectable hepatic cancer.Abbreviations PLC
primary liver cancer
- SLC
secondary liver cancer
- IOUS
intraoperative ultrasound
- AFP
-fetoprotein
Presented in part at the 4th World Congress of Hepato-Pancreato-Biliary Surgery, 7–11 June 1992, Hong Kong 相似文献
148.
老年心肌缺血者QTc和QTcd变化及临床意义 总被引:1,自引:0,他引:1
测定了64例老年心肌缺血(MIS)患者和21例心肌梗塞(MI)患者心电图的QTc间期和QTc离散度(QTcd),并与心血管神经官能症(CVN)及正常老年人进行比较;探讨QTc、QTcd与致命性室性心律失常(FVA)、心原性猝死(CSD)的关系;分析MI不同部位的QTcd变化以及稳定性心绞痛(SAP)和不稳定性心绞痛(USAP)的QTcd差异。结果:老年女性患者QTc较男性长(P<0.05),而QTcd两者无差异;老年MIS患者QTc和QTcd较正常组明显延长(P<0.01);MI前壁、下壁和后壁3组QTcd无明显差异(P>0.05);USAP患者QTcd较SAP长(P<0.05)。 相似文献
149.
Effect of interferon-gamma on hepatic fibrosis in chronic hepatitis B virus infection: a randomized controlled study. 总被引:4,自引:0,他引:4
Hong-Lei Weng Bao-En Wang Ji-Dong Jia Wan-Fen Wu Jian-Zhong Xian Peter R Mertens Wei-Min Cai Steven Dooley 《Clinical gastroenterology and hepatology》2005,3(8):819-828
BACKGROUND & AIMS: Hepatic fibrosis due to chronic HBV infection has enormous socioeconomic impact. Besides strategies targeting virus elimination, prevention or reversal of liver fibrosis is amenable. Given the antifibrotic activity of interferon-gamma (IFN-gamma), a randomized open-labeled multicenter trial was initiated to test IFN-gamma in HBV infection. METHODS: HBsAg-positive patients with biopsy proven hepatic fibrosis (n = 99, stages 2-4, Scheuer criterion) were treated with diammone-glycyrrhizinate and potassium-magnesium aspartate. Sixty-six randomly assigned patients were treated with 50 mug IFN-gamma intramuscularly on a daily basis for 3 months and on alternate days the subsequent 6 months. Efficacy was evaluated by liver biopsy and serologic markers. RESULTS: Fifty-four patients in the IFN-gamma group and 29 patients in the control group completed the study. The hepatic fibrosis score was significantly reduced in 63% of IFN-gamma treated patients compared with 24.1% in the control group by using a semiquantitative scoring system evaluating both liver architecture and fibrotic deposits. Mean values for the total fibrosis score decreased from 13.8 +/- 5.8 to 10.1 +/- 5.1 in the IFN-gamma group (P = .0001), whereas they were unchanged in control subjects (13.2 +/- 6.8 vs 12.6 +/- 4.8, P = .937). The Scheuer system showed 12 out of 54 patients improved >or=1 stage(s) in the IFN-gamma group compared with 1 of 29 in the control group. Antifibrotic activity might be attributed to decreased transforming growth factor-beta signaling via phosphorylated Smad2 and reduced number of activated, alpha-smooth muscle actin positive hepatic stellate cells. CONCLUSIONS: IFN-gamma treatment for 9 months improves fibrosis scores in patients with chronic HBV infection most likely by antagonizing profibrogenic transforming growth factor-beta effects. 相似文献
150.
老年肺心病患者吸入一氧化氮后血流动力学与血管调节因子的变化 总被引:1,自引:0,他引:1
自的为探讨血管内皮细胞在慢性阻塞性肺疾病(COPD)肺心病发生发展中的作用,对该病患者血浆内皮细胞释放的舒血管因子──一氧化氮(No)的含量与血管紧张素转换酶(ACE)活性进行测定,并观察提供外源性NO对肺心病晚期患者肺血流动力学的影响。方法采用分光光度法测定9例老年COPD肺心病晚期患者血浆NO的含量与ACE活性,另有12例健康老年人作为对照,并应用右心导管技术观察了吸入40×10-6NO20分钟对晚期肺心病患者肺血流动力学的影响。结果老年肺心病患者血浆NO含量与ACE活性显著降低;吸入NO后,血浆NO代谢产物显著增加的同时,肺动脉平均压(PAPm)从4.1±0.7kPa(1kPa=7.5mmHg)降为3.3±0.5kPa(P值<0.01),肺血管阻力及其指数显著降低,输氧量(DO2)、心输出量(CO)增加,右室作功降低。全血谷胱甘肽过氧化物酶(GSH-px)活力显著降低(37.3%)。结论老年慢性心病患者血管内皮依赖性舒张因子缺乏,其肺血管内皮可能存在一定的损伤,外源性补充NO可显著改善肺循环,增加输氧量,而副作用很少,对老年肺心病患者有益 相似文献