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91.
92.
Happo MS Hirvonen MR Halinen AI Jalava PI Pennanen AS Sillanpaa M Hillamo R Salonen RO 《Inhalation toxicology》2008,20(14):1215-1231
Inflammation is regarded as an important mechanism in mortality and morbidity associated with exposures of cardiorespiratory patients to urban air particulate matter. We investigated the association of the chemical composition and sources of urban air fine (PM(2.5-0.2)) and coarse (PM(10-2.5)) particulate samples with the inflammatory activity in the mouse lung. The particulate samples were collected during selected seasons in six European cities using a high-volume cascade impactor. Healthy C57BL/6J mice were intratracheally instilled with a single dose (10 mg/kg) of the particulate samples. At 4, 12, and 24 h after the exposure, the lungs were lavaged and the bronchoalveolar lavage fluid (BALF) was assayed for indicators of inflammation and tissue damage: cell number, total protein, and cytokines (tumor necrosis factor [TNF]-alpha, interleukin [IL]-6, and KC). Dicarboxylic acids and transition metals, especially Ni and V, in PM(2.5-0.2) correlated positively and some secondary inorganic ions (NO3(-), NH4(+)) negatively with the inflammatory activity. Total organic matter and SO4(2-) had no consistent correlations. In addition, the soil-derived constituents (Ca2+, Al, Fe, Si) showed positive correlations with the PM(2.5-0.2)-induced inflammatory activity, but their role in PM(10-2.5) remained obscure, possibly due to largely undefined biogenic material. Markers of poor biomass and coal combustion, i.e., monosaccharide anhydrides and As, were associated with elevated PAH contents in PM(2.5-0.2) and a consistent immunosuppressive effect. Overall, our results support epidemiological findings that the local sources of incomplete combustion and resuspended road dust are important in urban air particulate pollution-related health effects. 相似文献
93.
Inducible heme oxygenase in the kidney: a model for the homeostatic control of hemoglobin catabolism 总被引:7,自引:6,他引:7 下载免费PDF全文
Neville R. Pimstone Peter Engel Raimo Tenhunen Paul T. Seitz Harvey S. Marver Rudi Schmid 《The Journal of clinical investigation》1971,50(10):2042-2050
We have recently identified and characterized NADPH-dependent microsomal heme oxygenase as the major enzymatic mechanism for the conversion of hemoglobin-heme to bilirubin-IXalpha in vivo. Enzyme activity is highest in tissues normally involved in red cell breakdown, that is, spleen, liver, and bone marrow, but it usually is negligible in the kidney. However, renal heme oxygenase activity may be transiently increased 30- to 100-fold following hemoglobinemia that exceeded the plasma haptoglobin-binding capacity and consequently resulted in hemoglobinuria. Maximal stimulation of enzyme activity in rats is reached 6-16 hr following a single intravenous injection of 30 mg of hemoglobin per 100 g body weight; activity returns to basal levels after about 48 hr. At peak level, total enzyme activity in the kidneys exceeds that of the spleen or liver. Cyclohexamide, puromycin, or actinomycin D, given just before, or within a few hours after, a single intravenous injection of hemoglobin minimizes or prevents the rise in renal enzyme activity; this suggests that the increase in enzyme activity is dependent on continued synthesis of ribonucleic acid and protein. The apparent biological half-life of renal heme oxygenase is about 6 hr. These observations indicate that functional adaptation of renal heme oxygenase activity reflects enzyme induction either directly or indirectly by the substrate, hemoglobin.Filtered rather than plasma hemoglobin appears to regulate renal heme oxygenase activity. Thus, stabilization of plasma hemoglobin in its tetrameric form with bis (N-maleimidomethyl) ether, which diminishes its glomerular filtration and retards it plasma clearance, results in reduced enzyme stimulation in the kidney, but enhances its activity in the liver. These findings suggest that the enzyme is localized in the tubular epithelial cells rather than in the glomeruli and is activated by luminal hemoglobin. Direct support for this concept was obtained by the demonstration of heme oxygenase activity in renal tubules isolated from rabbits that had been injected with hemoglobin. 相似文献
94.
95.
Raimo Pohjanvirta Satu Sankari Tauno Kulju Anita Naukkarinen Markku Ylinen Jouko Tuomisto 《Basic & clinical pharmacology & toxicology》1990,66(5):399-408
Lipid peroxidation has been shown to be enhanced following exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), but its role in TCDD toxicity is unclear. The present study was undertaken to further elucidate the relations between lipid peroxidation and TCDD lethality. A time course and dose-response experiment in Long-Evans (L-E; LD50 ca. 10 μg/kg) and Han/Wistar (H/W; LD50 > 3000 μg/kg) rats showed that hepatic lipid peroxidation, measured as the amount of thiobarbituric acid-reactive substances (TBA-RS), was induced by TCDD dose-dependently in L-E, but not in H/W rats. Hepatic glutathione peroxidase activity was suppressed in much the same manner in both strains. Lipid peroxidation correlated with body weight loss in L-E rats alone. When 500 μg/kg of TCDD was given to L-E rats, lipid peroxidation increased about 3-fold on Day 11 in the liver, while no change was seen in cardiac or renal TBA-RS. The pair-fed controls did not survive the 11-day test period and exhibited gastrointestinal hemorrhages. At 6 days, liver atrophy and elevated (over 2-fold) TBA-RS values were recorded in pair-fed controls but not in their TCDD-treated counterparts. TCDD decreased hepatic glutathione peroxidase activity by almost 50% at 6 days, while pair-feeding was without effect. Liver morphology was different between TCDD-treated and pair-fed rats. Moreover, the livers of TCDD-treated L-E rats contained much higher concentrations of probably peripheral fat-derived fatty acids than did the livers of pair-fed or ad libitum control rats. Restricted feeding over 6 days induced hepatic lipid peroxidation more in H/W than in L-E rats. Endotoxin increased liver TBA levels similarly in both strains having an additive effect with high doses of TCDD in H/W rats. Added as a 0.5% concentration in chow, butylated hydroxyanisole (BHA), but not ethoxyquin, tended to increase survival rate and time in L-E rats exposed to 20 μg/kg of TCDD; at 50 μg/kg the only survivor was again in the BHA group. However, neither antioxidant had any effect on initial body weight loss. It is concluded that lipid peroxidation mainly arises as a secondary phenomenon in TCDD toxicity, is not the cause of the typical histopathological liver lesion, but may contribute to lethality. 相似文献
96.
Elena De Mattia Erika Cecchin Michela Guardascione Luisa Foltran Tania Di Raimo Francesco Angelini Mario D’Andrea Giuseppe Toffoli 《World journal of gastroenterology : WJG》2019,25(29):3870-3896
Hepatocellular carcinoma (HCC) accounts for the majority of primary liver cancers. To date, most patients with HCC are diagnosed at an advanced tumor stage, excluding them from potentially curative therapies (i.e., resection, liver transplantation, percutaneous ablation). Treatments with palliative intent include chemoembolization and systemic therapy. Among systemic treatments, the small-molecule multikinase inhibitor sorafenib has been the only systemic treatment available for advanced HCC over 10 years. More recently, other smallmolecule multikinase inhibitors (e.g., regorafenib, lenvatinib, cabozantinib) have been approved for HCC treatment. The promising immune checkpoint inhibitors (e.g., nivolumab, pembrolizumab) are still under investigation in Europe while in the US nivolumab has already been approved by FDA in sorafenib refractory or resistant patients. Other molecules, such as the selective CDK4/6inhibitors (e.g., palbociclib, ribociclib), are in earlier stages of clinical development, and the c- MET inhibitor tivantinib did not show positive results in a phase III study. However, even if the introduction of targeted agents has led to great advances in patient response and survival with an acceptable toxicity profile, a remarkable inter-individual heterogeneity in therapy outcome persists and constitutes a significant problem in disease management. Thus, the identification of biomarkers that predict which patients will benefit from a specific intervention could significantly affect decision-making and therapy planning. Germ-line variants have been suggested to play an important role in determining outcomes of HCC systemic therapy in terms of both toxicity and treatment efficacy. Particularly, a number of studies have focused on the role of genetic polymorphisms impacting the drug metabolic pathway and membrane translocation as well as the drug mechanism of action as predictive/prognostic markers of HCC treatment. The aim of this review is to summarize and critically discuss the pharmacogenetic literature evidences, with particular attention to sorafenib and regorafenib, which have been used longer than the others in HCC treatment. 相似文献
97.
98.
The terms ‘alternative medicine’, ‘complementary medicine’ and ‘integrative medicine’ are of recent origin. According to Medline and PubMed, ‘alternative medicine’ first appeared in medical journals in 1975, when Nursing Times commenced a series of articles on topics such as transcendental meditation, spiritual healing and homeopathy. According to the same databases, the first appearance of ‘complementary medicine’ occurred in 1985, when The Lancet published an article titled ‘Complementary medicine in the United Kingdom’. ‘Integrative medicine’ was introduced in an English language journal in 1995, although it had appeared in German in an article 2 years earlier and in French already in 1951. Since the terms have no historical bearing whatsoever, we claim that they are used, together with many other slogans that thrive in contemporary Western health care, for ideological or commercial reasons to promote ideologies or to facilitate the selling of products and services. 相似文献
99.
Kerola T Hiltunen M Kettunen R Hartikainen S Sulkava R Vuolteenaho O Nieminen T 《Annals of medicine》2011,43(8):650-659
INTRODUCTION. The aim of the present study was to examine the power of B-type natriuretic peptide (BNP) and mild cognitive impairment as independent predictors of total and cardiovascular mortality in combination with established cardiovascular risk markers in an elderly general population without severe cognitive impairment. METHODS. A total of 499 individuals, aged more than 75 years, were examined and followed up for a median of 7.9 years in a prospective population-based stratified cohort study carried out in eastern Finland. The Cox proportional hazards regression model was used to determine the impact of multiple factors on total and cardiovascular mortality. RESULTS. In a multivariable model including established cardiovascular risk factors and conditions, both continuous BNP (adjusted hazard ratio (HR) 1.44 for a 1-SD change; 95% confidence interval (CI) 1.22-1.77; P < 0.001) and continuous MMSE score (HR 0.81 for a 1-SD change; 95% CI 0.70-0.94; P = 0.007) were independently associated with all-cause mortality. In a multivariable model, BNP remained a significant predictor of cardiovascular mortality, while MMSE score lost its significance. CONCLUSIONS. BNP, a measure of cardiovascular burden, and MMSE score 18-23, an indicator of mild cognitive impairment, are both independent predictors of total mortality. BNP and MMSE score may potentially be useful in screening elderly patients for elevated risk of mortality. 相似文献
100.
Puoliväli J Nurmi A Miettinen TK Soleti A Riccardino F Kalesnykas G Heikkinen T Vartiainen N Pussinen R Tähtivaara L Lehtimäki K Yrjänheikki J Canistro D Sapone A Spisni E Paolini M 《Journal of Alzheimer's disease : JAD》2011,27(3):499-510
The purpose of this study was to evaluate the efficacy of the radical scavenger IAC (bis(1-hydroxy-2,2,6,6-tetramethyl-4-piperidinyl) decantionate) in alleviating behavioral deficits and reducing amyloid-β (Aβ) accumulation in an Alzheimer's disease (AD) transgenic Tg2576 mouse model. Daily treatment with IAC (3-30 mg/kg, i.p.) was started at the age of 6 months and continued until the mice were 13 months old. At the age of 9 months and again at 12 months, the mice were tested in open field and water maze tests. At the age of 13 months, the mice were sacrificed and the brains processed for immunohistochemistry. Mortality was significantly reduced in all IAC-treated groups. In addition, IAC treatment improved the water maze hidden platform training performance but had no effect on motor activity in the open field or water maze swim speed in transgenic mice. Lastly, IAC treatment (10 mg/kg) significantly reduced the cortical Aβ plaque burden. In vitro, IAC is able to increase the number of neurites and neurite branches in cultured cortical primary neurons. In conclusion, IAC slowed down the development of the AD-like phenotype in Tg2576 mice and accelerated neurite growth in cultured neurons. 相似文献