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1.

Background

Recent data support the hypothesis that genetic damage occurring early in life during childhood can play an important role in the development of chronic diseases in adulthood, including cancer.

Objectives

The objective of this paper, part of the MAPEC_LIFE project, is to describe the frequency of micronuclei and meta-nuclear alterations in exfoliated buccal cells of 6–8year-old Italian children recruited in five Italian towns (i.e., Brescia, Torino, Pisa, Perugia and Lecce) with different air pollution levels.

Methods

About 200 children per town were recruited from primary schools. Biological samples were collected twice from the same children, in two different seasons (winter 2014-15 and late spring 2015). Cytogenetic damage was evaluated by the buccal micronucleus cytome assay.

Results

Overall,n?=?1046 children represent the final cohort of the MAPEC_LIFE study. On the whole, the results showed a higher mean MN frequency in winter (0.42?±?0.54‰) than late-spring (0.22?±?0.34‰). MN frequency observed among the five Italian towns showed a trend that follows broadly the levels of air pollution in Italy: the highest MN frequency was observed in Brescia during both seasons, the lowest in Lecce (winter) and Perugia (late-spring).

Conclusions

To the best of our knowledge, the number of recruited children included in the analysis (n?=?1046) is the highest compared to previous studies evaluating the frequency of MN in exfoliated buccal cells so far. MN frequency was associated with winter season and living in towns at various levels of air pollution, suggesting an important role of this exposure in determining early cytogenetic effects.  相似文献   
2.
AIM OF THE STUDY: Yueju-Wan (YJ), a traditional Chinese medicinal formula, is commonly used for the treatment of depression-related syndromes in China. This study was conducted to evaluate the antidepressant activity of YJ ethanol extract (YJ-E) and its four different fractions, the petroleum ether fraction (YJ-EA), ethyl acetate fraction (YJ-EB), n-butanol fraction (YJ-EC) and final aqueous fraction (YJ-ED). MATERIALS AND METHODS: Two experimental despair animal models: the mice tail suspension test (TST) and the mice forced swimming test (FST) were used to evaluate the antidepressant activity of YJ-E and its fractions. These extracts or fractions were administered orally for 7 days, while the parallel positive control was given at the same time using fluoxetine hydrochloride (FLU) in TST and imipramine hydrochloride (IMI) in FST respectively. RESULTS: YJ-E high dose (YJ-E2), YJ-EA, YJ-EC and the positive control groups could decrease the duration of immobility in the TST and FST and have no significant changes in locomotor activity. YJ-E low dose (YJ-E1), YJ-EB, YJ-ED and the vehicle solvent (VEH) control group have no obvious effect on these same tests. CONCLUSIONS: In these despair animal models, YJ ethanol extract, the petroleum ether fraction and n-butanol fraction show potent antidepressant effects. The petroleum ether fraction and n-butanol fraction appear to be the active fractions of YJ-E.  相似文献   
3.
Xiaobuxin-Tang (XBXT), a traditional Chinese herbal decoction, has been used for the treatment of depressive disorders for centuries in China. Our previous studies have demonstrated that the total flavonoids (XBXT-2) isolated from the extract of XBXT reversed behavioral alterations and serotonergic dysfunctions in chronically stressed rats. Recently, accumulating studies have suggested the behavioral effects of chronic antidepressants treatment might be mediated by the stimulation of hippocampal neurogenesis. In present study, we explored the effect of XBXT-2 on hippocampal neurogenesis and neurotrophic signal pathway in chronically stressed rats. Our immunohistochemistry results showed that concomitant administration of XBXT-2 (25, 50 mg/kg, p.o., 28 days, the effective doses for behavioral responses) significantly increased hippocampal neurogenesis in chronically stressed rats. Four weeks after BrdU injection, result in double immunofluorescence labeling showed that some of the newly generated cells in hippocampus co-expressed with NSE or GFAP, markers for neurons or astrocytes, respectively. Furthermore, XBXT-2 treatment reserved stress-induced decrease of hippocampal BDNF and pCREB (Ser133) expression, two important factors which were closely related to hippocampal neurogenesis. As a positive control drug, imipramine (10 mg/kg, p.o.) exerted same effects. In conclusion, the increase of neurogenesis, as well as expression of BDNF and pCREB in hippocampus may be one of the molecular and cellular mechanisms underlying the antidepressant action of XBXT-2.  相似文献   
4.
Serum and brain levels of the tricyclic antidepressant drug imipramine (IMI) were studied in the rat under a variety of conditions. IV doses (range 1 nmol kg-1 to 15 mol kg-1, 350 ng–5mg kg-1) and administered 5 min before death, were linearly correlated with IMI levels in serum, frontal cortex, and cerebellum. In this experiment, the highest levels of IMI were achieved in the frontal and occipital cortex and the lowest levels were found in the brain stem. The regional distribution was more even in rats pretreated with thiopental or -hydroxybutyric acid, drugs that alter cerebral blood flow. After 20 min or more, tracer amounts of IMI injected IV to IMI-pretreated rats [1 or 17 days, daily dose 2×36 mol kg-1 (10 mg kg-1), last dose 89 mol kg-1 (25 mg kg-1), 2–3 h before death] exhibited a distribution pattern in serum and various brain regions similar to that of the unlabeled drug. In the latter experiments, content (per volume) of the tracer or unlabeled IMI was more than 25-fold higher in various brain areas than in serum. It is concluded that despite large differences in drug levels in serum or brain, a close relationship is maintained under the conditions studied.deceased  相似文献   
5.
Ipomoea stans Cav., popularly known as "tumbavaqueros", is a plant widely used in Mexico for the treatment of epileptic seizures and nervous disorders. This work researched the action of the ethyl acetate extract from the root of I. stans (IS-EAE) on the central nervous system (CNS). The administration of IS-EAE (2.5 and 5.0 mg/kg, i.p.) produced an anxiolytic effect in mice. This extract (20.0 and 40.0 mg/kg, i.p.) significantly reduced spontaneous motor activity. 2.5, 5.0, 10.0, and 20.0 mg/kg of IS-EAE protected mice against pentylenetetrazole-induced convulsions and increased the hypnotic effect induced by pentobarbital. The administration of IS-EAE was able to increase the release of GABA in brain cortex of mice. These results suggest that IS-EAE possess anxiolytic and anticonvulsant effects, and could have potential sedative effect, probably through a GABAergic system. The extract did not show antidepressant effects on mice exposed to forced swimming test.  相似文献   
6.
There are now numerous in vitro and in silico ADME alternatives to in vivo assays but how do different industries incorporate them into their decision tree approaches for risk assessment, bearing in mind that the chemicals tested are intended for widely varying purposes? The extent of the use of animal tests is mainly driven by regulations or by the lack of a suitable in vitro model. Therefore, what considerations are needed for alternative models and how can they be improved so that they can be used as part of the risk assessment process? To address these issues, the European Partnership for Alternative Approaches to Animal Testing (EPAA) working group on prioritisation, promotion and implementation of the 3Rs research held a workshop in November, 2008 in Duesseldorf, Germany. Participants included different industry sectors such as pharmaceuticals, cosmetics, industrial- and agro-chemicals. This report describes the outcome of the discussions and recommendations (a) to reduce the number of animals used for determining the ADME properties of chemicals and (b) for considerations and actions regarding in vitro and in silico assays. These included: standardisation and promotion of in vitro assays so that they may become accepted by regulators; increased availability of industry in vivo kinetic data for a central database to increase the power of in silico predictions; expansion of the applicability domains of in vitro and in silico tools (which are not necessarily more applicable or even exclusive to one particular sector) and continued collaborations between regulators, academia and industry. A recommended immediate course of action was to establish an expert panel of users, developers and regulators to define the testing scope of models for different chemical classes. It was agreed by all participants that improvement and harmonization of alternative approaches is needed for all sectors and this will most effectively be achieved by stakeholders from different sectors sharing data.  相似文献   
7.
Zusammenfassung Bei Stoffwechselgesunden, Übergewichtigen und übergewichtigen Altersdiabetikern wurde das immunologisch meßbare Insulin (IMI) nach intravenöser Glucose (0.33 g/kg), Tolbutamid (1 g) und Glucagonbelastung (1 mg) bestimmt. —Bei Stoffwechsel-gesunden steigen die IMI-Werte schon in den ersten Minuten nach der Glucose-, Tolbutamid-bzw. Glucagonbelastung an. Von der 15. Minute ab liegen die IMI-Werte wieder im Bereich der Norm. Die Übergewichtigen reagieren auf die Glucose-, Tolbutamid-und Glucagon-Stimulation so prompt wie die Normalgewichtigen; der Anstieg erfolgt in den ersten Minuten, die Werte liegen jedoch signifikant höher. Bei Übergewichtigen mit manifestem Diabetes liegen die IMI-Werte nach Glucose-und Tolbutamidbelastung wesentlich niedriger, nach Glucagon jedoch im Bereich der Stoffwechselgesunden mit normalem Körpergewicht. —Zwischen dem Koeffizienten K der Glucoseassimilation und dem Seruminsulin nach der Glucosebelastung konnte bei Übergewichtigen keine Korrelation gefunden werden. Damit ist der Hyper-insulinismus mehr als Charakteristikum der Fettsucht als des Diabetes mellitus anzusehen.
Immunologically measurable insulin (IMI) in normal, obese and obese, diabetic subjects after intravenous administration of glucose, tolbutamide and glucagon.
Summary Serum insulin levels (immunologically measurable insulin, IMI) in normal, obese and obese, diabetic subjects were determined following injection of glucose (0.33 g/kg), tolbutamide (1 g) and glucagon (1 mg). —In normal non-obese subjects an immediate (after one minute) increase of serum insulin levels was observed following the injection of glucose, tolbutamide or glucagon. 15 minutes after injection, the IMI-values were within the normal range. Obese subjects also react with an immediate increase of serum insulin levels following injection of glucose, tolbutamide or glucagon; however, the IMI-values were significantly higher than in normal subjects. Furthermore, in obese patients with slight diabetes, the IMI-levels after glucose or tolbutamide were definitely lower than those observed in normal non-obese subjects, although the levels following glucagon were of the same magnitude.-Apparently the increase of endogenous insulin in obese non-diabetic-patients after administration of glucose does not influence the glucose assimilation coefficient, K. Hyperinsulinism appears to be associated with obesity rather than with diabetes.
Durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft, Bad Godesberg.  相似文献   
8.
9.
Production of laccase using a submerged culture of Pleurotus orstreatus IMI 395545 was optimized by the Taguchi orthogonal array (OA) design of experiments (DOE) methodology. This approach facilitates the study of the interactions of a large number of variables spanned by factors and their settings, with a small number of experiments, leading to considerable savings in time and cost for process optimization. This methodology optimizes the number of impact factors and enables to calculate their interaction in the production of industrial enzymes. Eight factors, viz. glucose, yeast extract, malt extract, inoculum, mineral solution, inducer (1 mM CuSO4) and amino acid (l‐asparagine) at three levels and pH at two levels, with an OA layout of L18 (21 × 37) were selected for the proposed experimental design. The laccase yield obtained from the 18 sets of fermentation experiments performed with the selected factors and levels was further processed with Qualitek‐4 software. The optimized conditions shared an enhanced laccase expression of 86.8% (from 485.0 to 906.3 U). The combination of factors was further validated for laccase production and reactive blue 221 decolorization. The results revealed an enhanced laccase yield of 32.6% and dye decolorization up to 84.6%. This methodology allows the complete evaluation of main and interaction factors. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
10.
Many marketed pharmaceuticals reach extremely high tissue concentrations due to accumulation in lysosomes (lysosomotropism). Quantitative prediction of intracellular concentrations of accumulating drugs is challenging, especially for macrocyclic compounds that mainly do not fit in current in silico models. We tested a unique library of 47 compounds (containing 39 macrocycles) specifically designed to cover the entire range of accumulation intensities observed with pharmaceuticals so far. For the first time, we show that intracellular concentration of compounds measured by liquid chromatography with tandem mass spectrometry correlates with the induction of phospholipidosis and inhibition of autophagy, but the highest correlation was observed with the increase of lysosomal volume (R = 0.95), all measured by high-throughput imaging assays. Based only on imaging data, we developed a 5-class in vitro model for the prediction of compound accumulation with the accuracy of 81%. The measured change of total lysosomal volume can thus be used in high-throughput screening for determination of the actual intensity of intracellular accumulation of new macrocyclic compounds. The models are largely based on macrocycles, greatly improving the screening and prediction of intracellular accumulation of this challenging class. However, all tested nonmacrocyclic compounds fitted well in the models, indicating potential use of the models in broader chemical space.  相似文献   
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