消融右肺动脉神经节丛对肾上腺素能刺激和胆碱 能刺激诱发房颤的影响

目的:探讨右肺动脉神经节丛(RPVGP)消融对胆碱能及儿茶酚胺诱发房颤的影响。方法:20只犬麻醉开胸后,暴露RPVGP,分别在消融RPVGP前后,经股静脉静滴乙酰胆碱(ACh)及儿茶酚胺。测量房颤诱发率及两类递质诱发房颤的阈浓度。结果:RPVGP消融前,静滴Ach和异丙基肾上腺素(IPA)及肾上腺素(EPI)(1～100μmol/l)均可诱发AF,诱发率100%。Ach、IPA和EPI的诱发阈浓度分别为2.6±0.3μmol/l,3.3±0.2μmol/l,5.6±0.2μmol/l。RPVGP消融后,Ach及儿茶酚胺的AF诱发率分别降至10%及35%,且三种递质的诱发阈浓度分别提高至2.6±0.3μmol/l、22.5±2.4μmol/l和26.±2.6μmol/(lP<0.05)。结论:消融RPVGP使乙酰胆碱和儿茶酚胺诱发房颤的阈浓度增高,并降低此二类介质的房颤诱发率。     

Intrauterine growth restriction alters the metabonome of the serum and jejunum in piglets

Intrauterine growth restriction (IUGR) is not only an underlying factor for stunted postnatal growth and newborn deaths, but also associated with disease prevalence, such as hypertension and diabetes, in both adult humans and animals. To investigate the metabolic status of IUGR, the differences in serum and jejunal tissue metabonome were examined in IUGR and normal weight 21 day old piglets. IUGR piglets had a significantly lower birth weight (785 ± 42 g vs. 1451 ± 124 g), weaned weight (3053 ± 375 g vs. 6489 ± 545 g) and average daily gain (108 ± 16 g vs. 240 ± 21 g) than normal weight piglets (p < 0.05). IUGR piglets also had a shorter villus height and smaller villus height to crypt depth ratio (p < 0.05) in jejunum. An NMR-based metabonomic study found that serum levels of glycoprotein, albumin and threonine were higher in IUGR than in normal weight piglets, while serum levels of HDL, lipids, unsaturated lipids, glycerophosphorylcholine, myo-inositol, citrate, glutamine and tyrosine were lower in IUGR piglets (p < 0.05). In addition, marked changes in jejunal metabolites, including elevated levels of lipids and unsaturated lipids, and decreased levels of valine, alanine, glutamine, glutamate, choline, glycerophosphorylcholine, trimethylamine-N-oxide, scyllo-inositol, lactate, creatine, glucose, galactose, phenylalanine, tyrosine, glutathione, inosine and taurine were observed in IUGR piglets (p < 0.05). These novel findings indicate that IUGR piglets have a distinctive metabolic status compared to normal weight piglets, including changes in lipogenesis, lipid oxidation, energy supply and utilization, amino acid and protein metabolism, and antioxidant ability; these changes could contribute to impaired growth and jejunal function.     

Lymphangiogenesis is required for pancreatic islet inflammation and diabetes

Lymphangiogenesis is a common phenomenon observed during inflammation and engraftment of transplants, but its precise role in the immune response and underlying mechanisms of regulation remain poorly defined. Here we showed that in response to injury and autoimmunity, lymphangiogenesis occurred around islets and played a key role in the islet inflammation in mice. Vascular endothelial growth factors receptor 3 (VEGFR3) is specifically involved in lymphangiogenesis, and blockade of VEGFR3 potently inhibited lymphangiogenesis in both islets and the draining LN during multiple low-dose streptozotocin (MLDS) induced autoimmune insulitis, which resulted in less T cell infiltration, preservation of islets and prevention of the onset of diabetes. In addition to their well-known conduit function, lymphatic endothelial cells (LEC) also produced chemokines in response to inflammation. These LEC attracted two distinct CX3CR1(hi) and LYVE-1(+) macrophage subsets to the inflamed islets and CX3CR1(hi) cells were influenced by LEC to differentiate into LYVE-1(+) cells closely associated with lymphatic vessels. These observations indicate a linkage among lymphangiogenesis and myeloid cell inflammation during insulitis. Thus, inhibition of lymphangiogenesis holds potential for treating insulitis and autoimmune diabetes.     

Bivariate genome-wide association analyses of femoral neck bone geometry and appendicular lean mass

Objective

Femoral neck geometric parameters (FNGPs), such as periosteal diameter (W), cross-sectional area (CSA), cortical thickness (CT), buckling ratio (BR), and section modulus (Z), are highly genetically correlated with body lean mass. However, the specific SNPs/genes shared by these phenotypes are largely unknown.

Methods

To identify the specific SNPs/genes shared between FNGPs and appendicular lean mass (ALM), we performed an initial bivariate genome-wide association study (GWAS) by scanning ∼690,000 SNPs in 1,627 unrelated Han Chinese adults (802 males and 825 females) and a follow-up replicate study in 2,286 unrelated US Caucasians.

Results

We identified 13 interesting SNPs that may be important for both FNGPs and ALM. Two SNPs, rs681900 located in the HK2 (hexokinase 2) gene and rs11859916 in the UMOD (uromodulin) gene, were bivariately associated with FNGPs and ALM (p = 7.58×10⁻⁶ for ALM-BR and p = 2.93×10⁻⁶ for ALM-W, respectively). The associations were then replicated in Caucasians, with corresponding p values of 0.024 for rs681900 and 0.047 for rs11859916. Meta-analyses yielded combined p values of 3.05×10⁻⁶ and 2.31×10⁻⁶ for rs681900 and rs11859916, respectively. Our findings are consistent with previous biological studies that implicated HK2 and UMOD in both FNGPs and ALM. Our study also identified a group of 11 contiguous SNPs, which spanned a region of ∼130 kb, were bivariately associated with FNGPs and ALM, with p values ranging from 3.06×10⁻⁷ to 4.60×10⁻⁶ for ALM-BR. The region contained two neighboring miRNA coding genes, MIR873 (MicroRNA873) and MIR876 (MicroRNA876).

Conclusion

Our study implicated HK2, UMOD, MIR873 and MIR876, as pleiotropic genes underlying variation of both FNGPs and ALM, thus suggesting their important functional roles in co-regulating both FNGPs and ALM.     

Trastuzumab in the adjuvant treatment of HER2-positive early breast cancer patients: a meta-analysis of published randomized controlled trials

Background

Adjuvant trastuzumab therapy has yielded conflicting results for overall survival, concerns about central nervous system (CNS) metastasis, and questions about optimal schedule. Therefore, we carried out a meta-analysis to assess the benefits of concurrent or sequential trastuzumab with adjuvant chemotherapy for early breast cancer patients with HER2-positive tumors.

Methods

Computerized and manual searches were performed to identify randomized clinical trials comparing adjuvant chemotherapy with or without trastuzumab in HER2-positive early breast cancer patients. Odds ratios were used to estimate the association between the addition of trastuzumab to adjuvant chemotherapy and various survival outcomes. The fixed-effects or random-effects model was used to combine data.

Findings

With six eligible studies identified, this analysis demonstrated that patients with HER2-positive breast cancer derived benefit in disease-free survival, overall survival, locoregional recurrence and distant recurrence (all P<0.001) from the addition of trastuzumab to adjuvant chemotherapy, whereas trastuzumab did worse in CNS recurrence as compared to the control group (P = 0.018). Furthermore, concomitant use of trastuzumab significantly lowered the hazard of death (P<0.001) but bore a higher incidence of CNS recurrence (P = 0.010), while statistical significance failed to be discerned for either overall survival (P = 0.069) or CNS metastasis (P = 0.374) between the sequential and observation arms.

Conclusion

This analysis verifies the efficacy of trastuzumab in the adjuvant setting. Additionally, our findings indirectly corroborate the superiority of concurrent trastuzumab to sequential use and also illuminate that prolonged survival is the possible reason for the higher incidence of CNS with trastuzumab versus observation.     

Diphenyl difluoroketone: a potent chemotherapy candidate for human hepatocellular carcinoma

Diphenyl difluoroketone (EF24), a molecule having structural similarity to curcumin, was recently reported to inhibit proliferation of various cancer cells significantly. Here we try to determine the effect and mechanism of EF24 on hepatocellular carcinoma. 2 μM EF24 was found to inhibit the proliferation of PLC/PRF/5, Hep3B, HepG2, SK-HEP-1 and Huh 7 cell lines. However, even 8 μM EF24 treatment did not affect the proliferation of normal liver LO2 cells. Accordingly, 20 mg/kg/d EF24 inhibited the growth of the tumor xenografts conspicuously while causing no apparent change in liver, spleen or body weight. In addition, significant apoptosis and G(2)/M phase cell cycle arrest were found using flow cytometry. Besides, caspases and PARP activation and features typical of apoptosis including fragmented nuclei with condensed chromatin were also observed. Furthermore, the mechanism was targeted at the reduction of nuclear factor kappa b (NF-κB) pathway and the NF-κB-regulated gene products Bcl-2, COX-2, Cyclin B1. Our study has offered a strategy that EF24 being a therapeutic agent for hepatocellular carcinoma.