赖巴石隧洞存在的问题及技术改造措施

赖巴石隧洞设计流量25m^(3)/s,技改前最大过水13m^(3)/s。文章阐述了赖巴石隧洞过水能力不足问题的根源和技术改造设计方案,及技术改造实施经过。隧洞经过两期技术改造,过水能力达设计流量25m^(3)/s,技改效果十分显著。

Activation and dramatically increased cytolytic activity of tumor specific T lymphocytes after radio-frequency ablation in patients with hepatocellular carcinoma and colorectal liver metastases

AIM： To assess if a specific cytotoxic T cell response can be induced in patients with malignant liver tumors treated with radio-frequency ablation （RFA）. METHODS： Six Patients with liver metastases of colorectal cancer and 6 with hepatocellular carcinoma （HCC） underwent RFA. Blood was sampled before, 4 and 8 wk after RFA. Test antigens were autologous liver and tumor lysate obtained from each patient by biopsy. Peripheral T cell activation was assessed by an interferon gamma （IFNγ） secretion assay and flow cytometry. T cells were double-stained for CD4/CD8 and IFNγ to detect cytotoxic T cells. The ratio of IFNγ positive and IFNγ negative T cells was determined as the stimulation index （SI）. To assess cytolytic activity, T cells were co-incubated with human CaCo colorectal cancer and HepG2 HCC cells and release of cytosolic adenylate kinase was measured by a luciferase assay. RESULTS： Before RFA SI was 0.021 （±0.006） for CD4^＋ and 0.022 （± 0.004） for CD8^＋T cells against nonmalignant liver tissue and 0.018 （± 0.005） for CD4^＋ and 0.021 （± 0.004） for CD8^＋ cells against autologous tumor tissue. Four weeks after RFA SI against tumor tissue increased to 0.109 （± 0.005） for CD4＋ and 0.11 （± 0.012） for CD8＋ T cells against HCC, and to 0.115 （± 0.031） for CD4^＋ and 0.15 （± 0.02） for CD8^＋ cells for colorectal metastases （P 〈 0.0001）. No increased SI was observed with nonmalignant tumor tissue at all time points. Before RFA cytolytic activity against the respect（ve cancer cells was low with 2.62 （± 0.37） relative luminescence units （RLU）, but rose more than 100 fold 4 and 8 wk after RFA. Spontaneous release was 〈 2% of maximum release in all experiments. CONCLUSION： Patients with primary and secondary tumors of the liver show a significant tumor-specific cytotoxic T-cell stimulation with a dramatically increased tumor specific cytolytic activity of CD8^＋ T cells after RFA.

Interaction between enteric epithelial cells and Peyer's patch lymphocytes in response to Shigella lipopolysaccharide: Effect on nitric oxide and IL-6 release

AIM： TO investigate the effect of interaction between enteric epithelial cells and lymphocytes of Peyer＇s patch on the release of nitric oxide （NO） and IL-6 in response to Shigella lipopolysaccharide （LPS）. METHODS： Human colonic epithelial cells （Caco-2） were mixed cocultured with lymphocytes of Peyer＇s patch from wild-type （C57 mice） and inducible NO synthase knockout mice, and challenged with Shigella F2a-12 LPS. Release of NO and raiL-6 was measured by Griess colorimetric assay and enzyme-linked immunosorbent assay （ELISA）, respectively. RESULTS： In the absence of LPS challenge, NO was detected in the culture medium of Caco-2 epithelial cells but not in lymphocytes of Peyer＇s patch, and the NO release was further up-regulated in both cocultures with lymphocytes from either the wild-type or iNOS knockout mice, with a significantly higher level observed in the coculture with iNOS knockout lymphocytes. After Shigella F2a-12 LPS challenge for 24-h, NO production was significantly increased in both Caco-2 alone and the coculture with lymphocytes of Peyer＇s patch from the wild-type mice but not from iNOS knockout mice. LPS was found to stimulate the release of mIL-6 from lymphocytes, which was suppressed by coculture with Caco-2 epithelial cells. The LPS-induced mIL-6 production in lymphocytes from iNOS knockout mice was significantly greater than that from the wild-type mice. CONCLUSION： Lymphocytes of Peyer＇s patch maintain a constitutive basal level of NO production from the enteric epithelial cell Caco-2. LPS-induced mIL-6 release from lymphocytes of Peyer＇s patch is suppressed by the cocultured epithelial cells. While no changes are detectable in NO production in lymphocytes from both wild-type and iNOS knockout mice before and after LPS challenge, NO from lymphocytes appears to play an inhibitory role in epithelial NO release and their own mIL-6 release in response to LPS.

Differentiation induced by physiological and pharmacological stimuli leads to increased antigenicity of human neuroblastoma cells

Sympathetic neuronal differentiation is associated with favorable prognosis of neuroblastoma （NB）, the most common extra-cranial solid tumor of early childhood. Differentiation agents have proved useful in clinical protocols of NB treatment, but using them as a sole treatment is not sufficient to induce tumor elimination in patients. Therefore, complementary approaches, such as immunotherapy, are warranted. Here we demonstrate that differentiation of NB cell lines and ex vivo isolated tumor cells in response to physiological or pharmacological stimuli is associated with acquisition of increased antigenicity. This manifests as increased expression of surface major histocompatibility class I complexes and ICAM-1 molecules and translates into increased sensitivity of NB cells to lysis by cytotoxic T lymphocytes （CTLs） and natural killer （NK） cells. The latter is paralleled by enhanced ability of differentiated cells to form immune conjugates and bind increased amounts of granzyme B to the cell surface. We demonstrate, for the first time, that, regardless of the stimulus applied, the differentiation state in NBs is associated with increased tumor antigenicity that enables more efficient elimination of tumor cells by cytotoxic lymphocytes and paves the way for combined application of differentiation-inducing agents and immunotherapy as an auxiliary approach in NB patients.

The Content of Selenium and Other Ten Chemical Elements in Boletus Edulis from Bulgaria and Inhibition of Lipid Peroxidation

The goal of this study was to determine the content of such biological active metals as Se, Hg, AI, Cu, Zn, As, Cd, Pb, Mg, Ca and Fe in Boletus Edulis mushrooms and to study the effect of mushrooms as inhibitors of blood serum copper-initiated lipid peroxidation. The metals content was determined by ICP-OES technique and blood lipids peroxidation in vitro was assessed by thiobarbituric acid-reactive substances measurement. The dependency between quality and content of the determined biological active metals has been traced. Samples were analyzed of wild growing mushrooms Boletus Edulis from two mountain regions in Bulgaria. On the average the content of Se in Boletus Edulis was found to be 25 mg/kg dried mushroom, this content being higher in tubules than in fleshy part. We found that Boletus Edulis mushrooms inhibited lipid peroxidation in the concentration dependent manner. The effective concentration of Boletus Edulis is in 5 times lower compared to the concentration of Cantharellus Cibarius resulting in similar lipid peroxidation inhibition. This effect can be explained by 56 times higher content of Se and by 1.5 and 3 times lower content of such initiators of lipid peroxidation as Cu and Fe in Boletus Edulis compared to Cantharellus Cibarius. A system with a source of infrared radiation heating, developed by authors, was used for the mushroom mineralization. We conclude that Boletus Edulis is an effective inhibitor of blood lipid peroxidation and in 5 times stronger rather than Cantharellus Cibarius.

Investigation of the relationship between DNA-dependent protein kinase and lymphatic metastasis in colorectal cancer

Objective: To investigate DNA-dependent protein kinase (DNA-PK) expression,and its relationship with lymphat-ic metastasis in colorectal cancer. Methods: Tumor tissues from 60 patients,divided into two groups according to lymphatic metastasis,were immunohistochemically stained to detect the DNA-PK expression including Ku70,Ku80 and PKcs proteins. Results: Positivity of both Ku70 and Ku80 in colorectal cancer was negatively correlated with lymphatic metastasis with an r value of -0.57 and -0.38,respectively. Similar correlation was found between Ku expression,especially Ku70,and long-term survival. PKcs,however,displayed no significant correlation. Statistical analysis failed to detect any correlation between DNA-PK expression,and clinical characteristics,such as age,sex,tumor location,tumor thickness and distant metastasis (P>0.05). Conclusion: DNA-PK expression,especially Ku70 expression,is negatively correlated with lymphatic metastasis,and the survival of patients with colorectal cancer. Ku70 expression may be a potential indicator for the preoperative evaluation,and prognosis in colorectal cancer.

公道难讨

本是一桩简单的民事官司,却一拖八年,一审再审,给当事人造成了巨大的损失。责任该有谁来负?执法部门怎样做到执法为民?本案将给我们一些思考……

Modulation of M4 muscarinic acetylcholine receptors by interacting proteins

Protein-protein interactions represent an important mechanism for posttranslational modifications of protein expression and function.In brain cells,surface-expressed and membrane-bound neurotransmitter receptors are common proteins that undergo dynamic protein-protein interactions between their intracellular domains and submembranous regulatory proteins.Recently,the Gφi/o -coupled muscarinic M4 receptor（M4R）has been revealed to be one of these receptors.Through direct interaction with the intracellular loops or C-terminal tails of M4Rs,M4R interacting proteins（M4RIPs）vigorously regulate the efficacy of M4R signaling.A synapse-enriched protein kinase,Ca2＋/calmodulin-dependent protein kinase II （CaMKII）,exemplifies a prototype model of M4RIPs,and is capable of binding to the second intracellular loop of M4Rs. Through an activity-and phosphorylation-dependent mechanism,CaMKII potentiates the M4R/Gφi/o-mediated inhibition of M4R efficacy in inhibiting adenylyl cyclase and cAMP production.In striatal neurons where M4Rs are most abundantly expressed,M4RIPs dynamically control M4R activity to maintain a proper cholinergic tone in these neurons.This is critical for maintaining the acetylcholine-dopamine balance in the basal ganglia,which determines the behavioral responsiveness to dopamine stimulation by psychostimulants.