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971.
Reiichiro Kondo Yasuko Iwakiri Masayoshi Kage Hirohisa Yano 《Pathology international》2023,73(9):381-393
Liver is the largest solid organ in the abdominal cavity, with sinusoid occupying about half of its volume. Under liver disease, hemodynamics in the liver tissue dynamically change, resulting in injury to liver sinusoidal endothelial cells (LSECs). We discuss the injury of LSECs in liver diseases in this article. Generally, in noninflamed tissues, vascular endothelial cells maintain quiescence of circulating leukocytes, and unnecessary blood clotting is inhibited by multiple antithrombotic factors produced by the endothelial cells. In the setting of inflammation, injured endothelial cells lose these functions, defined as inflammatory endotheliopathy. In chronic hepatitis C, inflammatory endotheliopathy in LSECs contributes to platelet accumulation in the liver tissue, and the improvement of thrombocytopenia by splenectomy is attenuated in cases with severe hepatic inflammation. In COVID-19, LSEC endotheliopathy induced by interleukin (IL)-6 trans-signaling promotes neutrophil accumulation and platelet microthrombosis in the liver sinusoids, resulting in liver injury. IL-6 trans-signaling promotes the expression of intercellular adhesion molecule-1, chemokine (C-X-C motif) ligand (CXCL1), and CXCL2, which are the neutrophil chemotactic mediators, and P-selectin, E-selectin, and von Willebrand factor, which are involved in platelet adhesion to endothelial cells, in LSECs. Restoring LSECs function is important for ameliorating liver injury. Prevention of endotheliopathy is a potential therapeutic strategy in liver disease. 相似文献
972.
目的 基于生物信息学筛选分析宫颈癌差异表达基因 ( differentially expressed gene, DEGs) 及差
异表达 miRNA, 并进一步对差异基因和蛋白进行验证, 以期寻找潜在的生物标志物和治疗靶点。 方法 从
肿瘤基因组图谱 (the cancer genome atlas, TCGA) 数据库获取宫颈癌相关数据, edgeR 算法筛选 DEGs 和差
异 miRNAs。 利用 Cytoscape3. 8. 2 软件构建 mRNA-miRNA 共表达网络。 利用 DAVID 软件对 DEGs 和通过
miRWalk 网站预测的差异 miRNA 的目标基因进行 GO 富集分析和 KEGG 富集分析。 利用 qPCR 和 Western 印
迹技术对 DEGs 进行进一步验证。 结果 筛选出 149 个上调的 DEGs 和 171 个下调的 DEGs, 以及 46 个上调
的差异 miRNAs 和 64 个下调的差异 miRNAs。 DEGs 和 miRNA 目标基因在细胞组成上的富集具有一致性,
都富集在胞质、 核和核质中。 但共表达网络发现 DEGs 和差异 miRNAs 之间不存在明显的调控关系。 因此,
后续实验重点放在了对 DEGs 的验证上, 对差异表达性较为显著的 TCEAL6、 CLEC3B、 LMOD1、 CNN1 进行
了验证。 qPCR 显示它们在宫颈癌中表达量均显著降低, 符合预期, 对 CNN1 进行的 Western 印迹也显示其
在宫颈癌中的低表达。 结论 TCEAL6、 CLEC3B、 LMOD1、 CNN1 在宫颈癌中均显著低表达, 有望成为宫颈
癌生物标志物。 相似文献
973.
Colin A Brown Steven J Charlton Michael R Boarder 《British journal of pharmacology》1997,120(6):1049-1052
- We have previously shown that both suramin and pyridoxal-phosphate-6-azophenyl-2′, 4′ disulphonic acid (PPADS) act as antagonists at transfected P2Y1 receptors. Here we show that under certain experimental conditions these two P2 antagonists can enhance the response to agonists acting at these receptors.
- The expression of either P2Y1 or P2Y2 receptors in 1321N1 human astrocytoma cells results, on a change of medium, in an elevation of basal (no added agonist) accumulation of [3H]-inositol(poly)phosphates([3H]-InsPx) compared to cells not expressing these receptors. This elevation is much greater in P2Y1 transfectants than in P2Y2 transfectants.
- Both PPADS and suramin reduced this basal level of [3H]-InsPx accumulation in the P2Y1 expressing cells.
- When a protocol was used which required changing the culture medium, antagonists were added at a concentration which reduced the basal accumulation by about 50%, there was a significant stimulation in response to increasing concentrations of 2-methylthioadenosine 5′-triphosphate (2MeSATP), in the absence of antagonists there was no significant effect of the agonist.
- However, when 2MeSATP was added in the absence of a change of medium and with no antagonist present, there was a several fold increase in [3H]-InsPx accumulation. These results show that a release of endogenous agonist activity (possibly ATP/ADP) from the P2Y1 expressing cells can create conditions in which a response to an agonist such as 2MeSATP can only be seen in the presence of a competitive antagonist.
974.
Milne Robert W. Jensen Rikke Holm Larsen Claus Evans Allan M. Nation Roger L. 《Pharmaceutical research》1997,14(8):1014-1018
Purpose. Humans and guinea pigs metabolise morphine extensively, forming the isomers morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) in relatively similar ratios. Both metabolites are formed in the liver, and their greater polarity relative to the parent aglycone may limit their permeability across hepatic membranes. This study compared the disposition of hepatically-generated M3G and M6G in perfused livers isolated from guinea pigs.
Methods. Livers were perfused at 30 ml/min in a non-recirculating manner with Krebs bicarbonate buffer containing morphine (6 to 7 M). Perfusing medium, venous perfusate and bile were collected at regular intervals and concentrations of morphine, M3G and M6G determined by reversed-phase HPLC.
Results. Concentrations of morphine, M3G and M6G in perfusate and the rates of biliary excretion of M3G and M6G were consistent between 20 and 50 min of perfusion. The mean (±s.d.) ratio for the rate of formation of M3G relative to M6G was 3.7 ± 1.5. A mean 33 ± 3% of morphine extracted by the liver was recovered as summed M3G and M6G. Of the M3G and M6G formed during a single passage, 19 ± 11% and 9 ± 9%, respectively, was excreted into bile; the values were significantly different (P = 0.002).
Conclusions. A greater fraction of hepatically-generated M3G excreted into bile compared to that for M6G reflects differences in their relative transport across sinusoidal and canalicular membranes of hepatocytes, possibly via carrier-mediated systems. 相似文献
975.
D. A. Stewart D. Guo J. A. Sutherland B. A. Ruether A. R. Jones M.-C. Poon C. deMetz J. Klassen A. Chaudhry C. B. Brown J. A. Russell 《Annals of oncology》1997,8(12):1277-1279
Background: Few data are available on the cost, safety, and long-termefficacy of single agent high-dose melphalan (HDM) followed by autologousbone marrow (ABMT) or blood stem cell (ABSCT) transplantation in the salvagetherapy of Hodgkins disease (HD).Patients and methods: From February 1981 to September 1996, 23 patientswith relapsed (n = 15) or refractory (n = 8) HD received salvage therapywith HDM 140–200 mg/m2 followed by non-cryopreservedABMT (n = 18) or cryopreserved ABSCT (n = 5). The cost of HDM/ABSCT in 1996,from initial consultation until transfer back to referring physician, wasdetermined and compared to the estimated costs of two multi-agent regimenscommonly used for HD.Results: HDM was well tolerated with no early transplant-relatedmortality. The five-year overall and progression-free survival rates were52% and 50%, respectively. The average total cost in Canadianfunds of HDM/ABSCT in 1996 was $34,400/patient. This cost wasestimated to be $4,700–6,800 cheaper per patient than themulti-agent high-dose regimens.Conclusion: These data suggest that HDM is safe, feasible, active, andreasonably inexpensive salvage therapy for patients with relapsed/refractoryHD. 相似文献
976.
J. R. Fischer M. Schindel H. Bülzebruck H. Lahm P. H. Krammer P. Drings 《Annals of oncology》1997,8(5):457-461
Background: We have previously shown that suppression of Interleukin-2(IL-2) secretion was mediated by transforming growth factor (TGF) 1secreted by small-cell lung cancer (SCLC) tumor cells. We have also shown thatIL-2 secretion was significantly impaired in patients with SCLC at the timeof diagnosis. Reconstitution of cytokine secretion correlated with reductionof tumor load. These data suggested that the immune system was suppressed bythe tumor. To address the clinical relevance of cytokine suppression in SCLC,we investigated the correlation of the level of IL-2 secretion with survival.Patients and methods: The significance of correlations between singleparameters in the test groups was calculated by using the linear regressionanalysis, the Wilcoxon rank sum test and the exact test according to Fisher.Using the Kaplan–Meier method, the log-rank test and the Cox-regressionmodel, we analysed the relation of IL-2 secretion in whole blood cell culturesfrom 52 patients with SCLC at the time of diagnosis to established prognosticfactors relevant for survival in SCLC.Results: Impairment of IL-2 secretion significantly correlates to survivalin SCLC (P = 0.004). Further univariate and multivariate analysis showed thatthis prognostic factor is independent from other factors of prognosticrelevance in SCLC, namely stage of disease, neurone specific enolase (NSE),lactate dehydrogenase (LDH), age, and sex. More important, the prognosticvalue of IL-2 secretion is comparable to the most predominant prognosticfactors for survival in SCLC identified so far. In the final model of the coxregression analysis, the P-value for IL-2 secretion in relation to stage ofdisease was 0.012 and 0.019, respectively.Conclusions: IL-2 secretion at the time of diagnosis represents anindependent prognostic factor for survival in SCLC. Although its prognosticvalue has to be confirmed in a larger group of patients, our resultsdemonstrate that IL-2 secretion may play an important role in diagnosis andtreatment of SCLC. Moreover, in contrast to other prognostic factors,impairment of IL-2 secretion may help to understand immunosuppression in SCLCand, thus, important elements of the pathogenesis of this disease. 相似文献
977.
Plant foods and colon cancer: an assessment of specific foods and their related nutrients (United States) 总被引:3,自引:0,他引:3
Martha L. Slattery John D. Potter Ashley Coates Khe-Ni Ma T. Dennis Berry Debra M. Duncan Bette J. Caan 《Cancer causes & control : CCC》1997,8(5):575-590
Plant foods have been associated inversely with colon cancer. Since amajor focus of this study was to identify components of plant foods whichmay account for their association with colon cancer, nutrients which arecommonly found in plant foods also were evaluated. A population-basedcase-control study was conducted in Northern California, Utah, and the TwinCities area of Minnesota (United States). Complete data were available frominterviewer-administered questionnaires on 1,993 cases and 2,410 controls.Higher intakes of vegetables (for highest relative to lowest quintile ofintake) were associated inversely with colon cancer risk: the odds ratio(OR) was 0.7 for both men (95 percent [CI] confidence interval = 0.5-0.9)and women (CI = 0.5-1.0). Associations were stronger among those withproximal tumors. Total fruit intake was not associated with colon cancerrisk although, among men, higher levels of whole grain intake wereassociated with a decreased risk (OR = 0.6, CI = 0.4-0.9 for older men);high intakes of refined grains were associated with an increased risk (OR =1.5, CI = 1.1-2.1). Dietary fiber intake was associated with a decreasedrisk of colon cancer: OR = 0.5 (CI = 0.3-0.9) for older men; OR = 0.7 (CI =0.4-1.2) for older women; OR = 0.6 (CI = 0.4-1.0) for men with proximaltumors; OR = 0.5 (CI = 0.3-0.9) for women with proximal tumors. Othernutrients, for which plant foods were the major contributor - such asvitamin B6, thiamin, and niacin (women only) - also were associatedinversely with colon cancer. Neither beta-carotene nor vitamin C wasprotective for colon cancer. Adjustment of plant foods for nutrients foundin plant foods or for supplement use did not appreciably alter the observedassociations between plant foods and colon cancer. 相似文献
978.
The antioxidant activity ofArtemisia iwayomogi was determined by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical The methanol extract
ofA. iwayomogi showed strong antioxidant activity, and thus fractionated with several solvents. The antioxidant activity potential of the
individual fraction was in the order of ethyl acetate>n-butanol>water>chloroform>n-hexane fraction. The ethyl acetate andn-butanol soluble fractions exhibiting strong antioxidant activity were further purified by repeated silica gel and Sephadex
LH-20 column chromatography. Antioxidant chlorogenic acid was isolated as one of the active principles from then-butanol fraction, together with the inactive components, 1-octacosanol, scopoletin, scopolin, apigenin 7,4′-di-O-methylether luteolin 6,3′-di-O-methylether (jaceosidin), apigenin 7-methylether (genkwanin), 2,4-dihydroxy-6-methoxyacetophenone 4-O-β-D-glucopyranoside and quebrachitol. The antioxidant activity of chlorogenic acid was comparable to that of L-ascorbic acid,
which is a well known antioxidant. 相似文献
979.
Omoto M Imai T Seki K Nomura R Otahara Y 《Environmental health and preventive medicine》1997,2(3):105-116
Based on the fact that chemical products such as binding agents are produced by mixing three kinds of phosphates with different
ratios, we mixed metaphosphate, polyphosphate and pyrophosphate. Each was made to Na-phosphate, K-phosphate, and Ca-phosphate
and each was mixed with commercial feeds so that the content of P would be approximately 0.1, 0.15, 0.3, 0.4, 0.6 and 1.0%.
The prepared pellets were given to ICR, CF # 1 and AKR strains of mice at 29 days of age for 680 days and observations were
made through this experimental period at different stages. The observations were also carried out on the mice administered
with the experimental feeds for 1.5 months from 9 to 10.5 months of age. The observations were compared with those of the
control group at all times. As a result, plasma 1 α, 25 (OH)2 D3 and P levels were always significantly higher in the phosphate administered groups relative to the control. Urine P and Fe
increased while urine Ca decreased in the phosphate-treated groups.
The effect of phosphates on the bones was studied taking soft X-ray pictures of hind legs and applying microdensitometry to
them. Through these observations we recognized thinning of the cortex of bones, reduction of marrow trabecules and development
of osteophyte. Histological observations disclosed that changes in knee joint tissues were apparent; that is, a decrease in
or an irregular loss of the number of cells in superficial, intermediate, and radial strata of the joint cartilage, proliferation
of subchondral bone, and the development of osteophytes were noted. As for muscles, diameters of musclar fibers became smaller;
in particular, type II fibers showed greater shrinkage. Regarding kidneys, swelling and atrophy of glomerular capillaries,
proliferation of mesangial cells, nephroselerosis, swelling, thinning, and loss of tubular epithelium, interstitial tissue
inflammation, development of cylindruria, and deposition of calcium were observed. All these changes seem to be a particularly
advanced aspect of the changes which are more pronounced with increasing dose and age.
These changes were found even in the group administered with the feed containing 0.1% phosphorus, and, these changes were
dependent on the concentration level of P. It was observed that administration to older subjects for a short term (1.5 months)
produced effects stronger than those to younger subjects administered for a long term (10.5 months).
The effects of condensed Ca-phosphate on bones were similar to those of condensed Na- and K-phosphates, and, hence, it was
supposed that these effects were caused by phosphate radicals.
An erratum to this article is available at . 相似文献
980.