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Carmine Zoccali Renke Maas Sebastiano Cutrupi Patrizia Pizzini Piero Finocchiaro Francesco Cambareri Vincenzo Panuccio Carmela Martorano Friedrich Schulze Giuseppe Enia Giovanni Tripepi Rainer Boger 《Nephrology, dialysis, transplantation》2007,22(3):801-806
BACKGROUND AND METHODS: The endogenous inhibitor of nitric oxide synthase (NOs) asymmetrical dimethyl-arginine (ADMA) has been implicated as a possible modulator of inducible NOs during acute inflammation. We examined the evolution in the plasma concentration of ADMA measured at the clinical outset of acute inflammation and after its resolution in a series of 17 patients with acute bacterial infections. RESULTS: During the acute phase of inflammation/infection, patients displayed very high levels of C-reactive protein (CRP), interleukin-6 (IL-6), procalcitonin and nitrotyrosine. Simultaneous plasma ADMA concentration was similar to that in healthy subjects while symmetric dimethyl-arginine (SDMA) levels were substantially increased and directly related with creatinine. When infection resolved, ADMA rose from 0.62 +/- 0.23 to 0.80 +/- 0.18 micromol/l (+29%, P = 0.01) while SDMA remained unmodified. ADMA changes were independent on concomitant risk factor changes and inversely related with baseline systolic and diastolic pressure. Changes in the ADMA/SDMA ratio were compatible with the hypothesis that inflammatory cytokines activate ADMA degradation. CONCLUSIONS: Resolution of acute inflammation is characterized by an increase in the plasma concentration of ADMA. The results imply that ADMA suppression may actually serve to stimulate NO synthesis or that in this situation plasma ADMA levels may not reflect the inhibitory potential of this methylarginine at the cellular level. 相似文献
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Possible relevance of pigeons as an indicator species for monitoring air pollution. 总被引:4,自引:1,他引:3 下载免费PDF全文
P A Schilderman J A Hoogewerff F J van Schooten L M Maas E J Moonen B J van Os J H van Wijnen J C Kleinjans 《Environmental health perspectives》1997,105(3):322-330
Wild city pigeons were caught at four different locations in the Netherlands to represent areas of high (Amsterdam-high), moderate (Amsterdam-medium), and low (Maastricht and Assen) traffic density. It is assumed that local ambient air pollution decreases as a function of traffic density. In these pigeons levels of polycyclic aromatic hydrocarbon (PAH)-DNA adducts, oxidative DNA damage, and heavy metal residues were determined in kidney, lung, liver, and blood (no adduct analysis in blood). The contribution of leaded gasoline to total body lead content was estimated by measuring concentrations of Pb and its isotopes in blood. We also analyzed samples of ambient air particulate matter for PAH and heavy metal concentrations at the four different locations. Interregional differences in heavy metals in ambient air particulate matter were reflected relatively well by pigeon body loads. The higher lead and cadmium concentrations in blood, kidney, liver, and lung were found in the Amsterdam high traffic density area, followed by Amsterdam medium, Assen, and Maastricht. A high Pb concentration in blood coincided with relatively low 206Pb/207Pb values, indicating a high contribution of leaded gasoline to total blood Pb concentrations in pigeons from the Amsterdam high traffic density area. Significantly enhanced blood zinc values were found in pigeons from both locations in Amsterdam compared to pigeons from the other two areas. However, no differences in Zn tissue levels between the four different groups were found. Oxidative DNA damage, determined as the ratio of 7-Hydro-8-oxo-2'-deoxyguanosine/ deoxyguanosine, in pigeon liver was highest in Amsterdam-high, followed by Assen (low traffic density). Pb content, but not the Cd content, was positively associated with oxidative DNA damage in liver tissue. In lung tissue, a negative correlation was found between oxidative DNA damage and Zn content. These results indicate that the carcinogenic potential of Pb might be ascribed to oxygen radical formation, whereas Zn plays a protective role against oxidative DNA damage. Places with high and medium traffic density could be clearly discriminated on the basis of PAH levels in the ambient air. The PAH content in particulate air samples was not, however, reflected in total PAH-related DNA adduct levels because no differences could be observed in tissue adduct levels in pigeons from the four different locations. Our results indicate that wild city pigeons can be used as biological indicators of exposure to heavy metal pollution in outdoor air. 相似文献
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Cindy A. Scherb Carla Gene Rapp Marion Johnson Meridean Maas 《Rehabilitation nursing》1998,23(4):174-191
Measuring patient outcomes is important to rehabilitation nurses and the patients they serve. This article describes research conducted at the University of Iowa College of Nursing to develop the Nursing Outcomes Classification (NOC) and the validation of this research by surveys conducted through specialty nursing organizations, particularly the Association of Rehabilitation Nurses. Nurses responded to surveys designed to validate (a) the importance of outcome indicators to the achievement of an outcome and (b) nursing's contribution to the achievement of the indicators. The results of the surveys indicated that rehabilitation nurses believe that nursing makes a substantial contribution to most outcomes and indicators. 相似文献
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J P Mackenbach C W Looman A E Kunst J D Habbema P J van der Maas 《Social science & medicine (1982)》1988,27(9):889-894
In order to assess the impact of medical care innovations on post-1950 mortality in The Netherlands, we analysed trends in mortality from a selection of conditions suggested by Rutstein et al.'s lists of "unnecessary untimely mortality". This selection covers 11 types of innovation, and includes 35 conditions which have become amenable to medical care. Loglinear regression analysis shows that for most of these conditions mortality declined during each of two subperiods (1950-1968; 1969-1984). Mortality decline accelerated in the second subperiod for many conditions. Reductions in mortality from these conditions between 1950/54 and 1980/84 added 2.96 and 3.95 years to life expectancy at birth of Dutch males and Dutch females respectively. A priori evidence indicates that these mortality reductions are due to some extent to 'spontaneous' incidence declines. Although the exact contribution of medical care innovations to these changes in mortality thus cannot be determined, the impact of medical care on post-1950 mortality in The Netherlands could well have been substantial. 相似文献
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Regional differences in mortality from conditions amenable to medical intervention in The Netherlands: a comparison of four time periods. 总被引:8,自引:7,他引:1 下载免费PDF全文
J P Mackenbach A E Kunst C W Looman J D Habbema P J van der Maas 《Journal of epidemiology and community health》1988,42(4):325-332
In The Netherlands, as in many other countries, important geographical variation in mortality from conditions amenable to medical intervention exists. Associations with a number of simple medical care supply characteristics (general practitioner density, hospital bed density, and percentage of regional hospital beds located in university and small hospitals) are generally weak and inconsistent, both before and after controlling for possible confounding factors. We explored one of the possible reasons for this lack of consistency, which is the time dependency of the relationship between medical care supply and avoidable mortality. A comparison of associations in four time periods (1950-54, 1960-64, 1970-74 and 1980-84) shows that the percentage of variance in regional mortality levels which can be "explained" by the medical care supply variables has changed over time. Although the patterns of change differ little from what one would expect on the basis of the time of introduction of medical care innovations, the exact nature of the associations is puzzling. Apart from some expected negative associations between mortality and the presence of university hospitals, we also found a few unexpected positive associations with general practitioner density. Possible explanations for these findings are discussed, and it is concluded that further study is necessary to reveal the causes of a higher or lower mortality level for conditions considered to be amenable to medical intervention. 相似文献
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Differential increases in brain levels of neuropeptide Y and vasoactive intestinal polypeptide after kainic acid-induced seizures in the rat 总被引:7,自引:0,他引:7
Josef Marksteiner Günther Sperk Dagmar Maas 《Naunyn-Schmiedeberg's archives of pharmacology》1989,339(1-2):173-177
Summary Changes in immunoreactivities of neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) were investigated in the brain of rats after severe kainic acid (KA, 10 mg/kg, i.p.) induced limbic seizures. Decreased levels of both neuropeptides were observed in the frontal cortex, striatum, dorsal hippocampus and amygdala/pyriform cortex subsequently to the period of acute seizures (3 h after injection of the toxin). Then NPY increased consistently in the frontal cortex, hippocampus and amygdala/pyriform cortex. Highest levels (290% of controls) were found in the frontal cortex after two months. Anticonvulsant therapy with phenobarbital (20 mg/kg, i.p., twice daily for three weeks) partially suppressed the rise in NPY levels. Immunoreactivity of VIP increased (to 150%) in the frontal cortex only transiently 3 days after injection of kainic acid. At the subsequently examined time intervals (10–60 days after kainic acid) it declined to control values. Levels decreasing subsequently to acute seizures reflect increased release and degradation of the respective peptide. Increased NPY levels suggest upregulation of NPY/ somatostatin/GABA neurons due to the decreased seizure threshold of the animals. The early, reversible rise of VIP in the cortex points to a short-lasting activation of this peptide system contained in local cholinergic neurons. This may be a consequence either of the acute seizures or subsequent neuropathological changes.
Send offprint requests to G. Sperk at the above address 相似文献
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