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1.
The effect of desoxycorticosterone on the adrenaline-induced relaxation of coronary arteries was studied in vitro, after a known inhibitor of COMT, pyrogallol. Relaxation induced by adrenaline was enhanced by desoxycorticosterone. Relaxation in response to adrenaline was increased by desoxycorticosterone. Pyrogallol potentiated the responses of coronary strips to adrenaline and also reduced or abolished the enhancing effects of desoxycorticosterone. It is concluded that desoxycorticosterone enhances the response of coronary smooth muscle to adrenaline by inhibiting an enzymatic pathway for the inactivation of catecholamines.  相似文献   
2.
Enkephalin-binding systems in human plasma   总被引:1,自引:0,他引:1  
Three amino acid-containing fractions present in human plasma are shown to bind both leu and met-enkephalin: serum albumin and two species of a much lower molecular weight, in all likelihood polypeptides. The amount of enkephalin associated with serum albumin seems comparatively smaller than that associated with the two low molecular weight systems. These systems jointly are apparently capable of binding a significant part of the circulating enkephalins. The possibility is suggested that the interactions described may play a role in maintaining the integrity of circulating enkephalins.  相似文献   
3.
Chronic inflammation is associated with the occurrence of several diseases. However, the side effects of anti‐inflammatory drugs prompt the identification of new therapeutic strategies. Plant‐derived extracellular vesicles (PDEVs) are gaining increasing interest in the scientific community for their biological properties. We isolated PDEVs from the juice of Citrus limon L. (LEVs) and characterized their flavonoid, limonoid and lipid contents through reversed‐phase high‐performance liquid chromatography coupled to electrospray ionization quadrupole time‐of‐flight mass spectrometry (RP‐HPLC–ESI‐Q‐TOF‐MS). To investigate whether LEVs have a protective role on the inflammatory process, murine and primary human macrophages were pre‐treated with LEVs for 24 h and then were stimulated with lipopolysaccharide (LPS). We found that pre‐treatment with LEVs decreased gene and protein expression of pro‐inflammatory cytokines, such as IL‐6, IL1‐β and TNF‐α, and reduced the nuclear translocation and phosphorylation of NF‐κB in LPS‐stimulated murine macrophages. The inhibition of NF‐κB activation was associated with the reduction in ERK1‐2 phosphorylation. Furthermore, the ability of LEVs to decrease pro‐inflammatory cytokines and increase anti‐inflammatory molecules was confirmed ex vivo in human primary T lymphocytes. In conclusion, we demonstrated that LEVs exert anti‐inflammatory effects both in vitro and ex vivo by inhibiting the ERK1‐2/NF‐κB signalling pathway.  相似文献   
4.
We investigated the molecular relationships between lipid peroxidation and mitochondrial DNA (mtDNA) single strand breaks (ssb) in isolated rat hepatocytes and mitochondria exposed to tert-butylhydroperoxide (TBH). Our results show that mtDNA ssb induced by TBH are independent of lipid peroxidation and dependent on the presence of iron and of hydroxyl free radicals. These data contribute to the definition of the mechanisms whereby mtDNA ssb are induced and provide possible molecular targets for the prevention of this kind of damage in vivo.  相似文献   
5.
X-linked adrenoleukodystrophy (X-ALD) is characterized by marked phenotypic variation ranging from adrenomyeloneuropathy (AMN) to childhood cerebral ALD (CCALD). X-ALD is caused by mutations in the ABCD1 gene, but no genotype-phenotype correlation has been established so far and modifier gene variants are suspected to modulate phenotypes. Specific classes of lipids, enriched in very long-chain fatty acids that accumulate in plasma and tissues from X-ALD patients are suspected to be involved in the neuroinflammatory process of CCALD. CD1 proteins are lipid- antigen presenting molecules encoded by five CD1 genes in human (CD1A-E). Association studies with 23 tag SNPs covering the CD1 locus was performed in 52 patients with AMN and 87 patients with CCALD. The minor allele of rs973742 located 4-kb downstream from CD1D was significantly more frequent in AMN patients (χ2 = 7.6; P = 0.006). However, this association was no longer significant after Bonferroni correction for multiple testing. The other polymorphisms of the CD1 locus did not reveal significant association. Further analysis of other CD1D polymorphisms did not detect stronger association with X-ALD phenotypes. Although the association with rs973742 warrants further investigations, these results indicate that the genetic variants of CD1 genes do not contribute markedly to the phenotypic variance of X-ALD.  相似文献   
6.

Background

Hypertension is the leading cause of death in developed countries and reduction of salt intake is recommended as a key preventive measure.

Objective

To assess the dietary sodium and potassium intakes in a national sample of Italian children and adolescents and to examine their relationships with BMI and blood pressure (BP) in the framework of the MINISAL survey, a program supported by the Italian Ministry of Health.

Population and Methods

The study population included 1424 healthy subjects (766 boys, 658 girls) aged 6-18 years (mean age: 10.1±2.9) who were consecutively recruited in participating National Health Service centers in 10 Italian regions. Electrolyte intake was estimated from 24 hour urine collections tested for completeness by the concomitant measurement of creatinine content. Anthropometric indices and BP were measured with standardized procedures.

Results

The average estimated sodium intake was 129 mmol (7.4 g of salt) per day among boys and 117 mmol (6.7 g of salt) among girls. Ninety-three percent of the boys and 89% of the girls had a consumption higher than the recommended age-specific standard dietary target. The estimated average daily potassium intakes were 39 mmol (1.53 g) and 36 mmol (1.40 g), respectively, over 96% of the boys and 98% of the girls having a potassium intake lower than the recommended adequate intake. The mean sodium/potassium ratio was similar among boys and girls (3.5 and 3.4, respectively) and over 3-fold greater than the desirable level. Sodium intake was directly related to age, body mass and BP in the whole population.

Conclusions

The Italian pediatric population is characterized by excessive sodium and deficient potassium intake. These data suggest that future campaigns should focus on children and adolescents as a major target in the framework of a population strategy of cardiovascular prevention.  相似文献   
7.
Abstract

Cobalt, nickel and chromium effects on germination of Alyssum, during after-ripening and aging. Cobalt (2.5–20mM), nickel (2.5–25mM) and chromium (0.2-1mM) effects have been studied in seeds of three species of Alyssum, of which two, A. bertolonii and A. argenteum, endemics to serpentine soils and one, A. nebrodense, closely related to the others but endemic to the Madonie (Sicily) where it grows on limestone.

The results, expressed as percentage of germinated seeds (p), Kotowski coefficient of velocity (v) and germination average ratio (), have been subjected to statistical analysis.

The effect per mM is generally inhibitory, not significant for cobalt, weak but significant for nickel, more marked and significant for chromium, linearly correlated to concentration. The inhibition reaches its highest level when seeds are ripe, being significantly related to the control germination capacity ().

The values of the specific inhibition (effect/mM modditppτ) for all the three species are higher for chromium, which is more toxic than nickel, and increase from A. nebrodense to A. argenteum, showing that of the two serpentine endemics A. bertolonii is more tolerant both to nickel and chromium.  相似文献   
8.
Summary

The evolution of the wood ring in arbutus andrachnoides link, in florence (from July 1946 to June 1947).

The anatomical characters of the wood ring of the stem and of the young branch of Arbutus andrachnoides Link have been studied in Florence.

The results are the following: the cambial tissue in the stem starts dividing at the end of April and continues during the summer months, ending completely in September.

In the branch the cambium differentiates almost a month earlier, namely at the beginning of April.

In both cases the only wood ring produced is completed at the end of September. Comparing the evolution of this wood with the climatic factors it can be seen that the cambium activity starts in a period of remarkable rainfall and of regular increase of temperature and presents a remarkable activity still at the end of August.

Arbutus andrachnoides Link. is a spontaneous hybrid between A. Unedo and A. Andrachne and its distribution (in Greece and in the gréek islands) shows that A. Unedo and A. Andrachne had the possibility to overlap in this area and to produce this hybrid.  相似文献   
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