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1.
Lymphocytes obtained from the spleen of Balb/C mice have been subjected to transformation by LPS in the presence of varying concentrations of Pb2+, Cd2+, or Cr3+. Both DNA and protein turnover were followed. It was found that Pb2+ and Cr3+ are mitogenic over a broad range of concentrations, while Cd2+ is slightly mitogenic at very low (10?6M) concentration and rapidly becomes inhibitory of both [3H]TdR and [3H]ALA uptake. Pb2+ appears to stimulate the action of LPS, while Cr3+ appears to inhibit. Each of the metals protects the lymphocytes from cell death arising from incubation with LPS. The mechanism of the observed changes is as yet obscure.  相似文献   
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Polysialic acid (PSA) is a polymer of N-acetylneuraminic acid residues added post-translationally to the membrane-bound neural cell adhesion molecule (NCAM). The large excluded volume created by PSA polymer is thought to facilitate cell migration by decreasing cell adhesion. Here we used live cell imaging (spot fluorescence recovery after photobleaching and fluorescence correlation spectroscopy) combined with biochemical approaches in an attempt to uncover a link between cell motility and the impact of polysialylation on NCAM dynamics. We show that PSA regulates specifically NCAM lateral diffusion and this is dependent on the integrity of the cytoskeleton. However, whereas the glial-derivative neurotrophic factor chemotactic effect is dependent on PSA, the molecular dynamics of PSA-NCAM is not directly affected by glial-derivative neurotrophic factor. These findings reveal a new intrinsic mechanism by which polysialylation regulates NCAM dynamics and thereby a biological function like cell migration.  相似文献   
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The aim of this study was to evaluate the efficacy of a food supplement combination based on isoflavones and berberine (ISB) in the treatment of menopausal symptoms and dyslipidaemia. Isoflavones are extracted from soy and absorbed in the body after being activated by lactobacillus. Berberine, extracted from the plant Berberis aristata, lowers plasma cholesterol and triglycerides (TG) by increasing low-density lipoprotein (LDL) receptors and reducing hepatic synthesis of TG. One hundred twenty women with a mean age of 54.8?±?0.6 years were enrolled and randomized to treatment with ISB (estromineral lipid [EL]?=?60 cases) or calcium and vitamin D(3) (CaD?=?60 cases). Menopausal symptoms, plasma cholesterol, and TG were evaluated at baseline, and after 4 and 12 weeks. EL treatment significantly lowered plasma total cholesterol (-13.5% ± 0.7 vs -0.2% ± 0.5), LDL cholesterol (-12.4% ± 1.5 vs + 0.8 % ± 0.7) and TG (-18.9% ± 2.5 vs -1.3% ± 1.2) and improved menopausal symptoms compared with CaD treatment. Safety parameters were unchanged during the study. The combination of berberine and isoflavones was effective in lowering cardiovascular (CV) risk factors in menopausal women with moderate dyslipidaemia and in improving their quality of life.  相似文献   
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This article examines the curvature of the manual proximal and middle phalanges of species belonging to Pan, Gorilla, Ateles, Macaca, Pongo, Hylobates, and Cebus to determine whether middle phalangeal curvature, when considered in conjunction with proximal phalangeal curvature, yields a locomotor signal. Prior studies have demonstrated the discriminatory power of proximal phalanges for separating suspensory species (including knuckle walkers) from pronograde quadrupedal species, but less emphasis has been placed on the distinguishing phalangeal characteristics of taxa within the suspensory category. This study demonstrates, first, that middle phalanges discriminate suspensory from nonsuspensory species, although not as cleanly as proximal phalanges. Finer discrimination of locomotor signals, including subtle differences among animals employing different modes of suspension, is possible through a comparison of the curvatures of the proximal phalanges and corresponding middle phalanges. Their relative curvature differs in quadrupeds, brachiators, and knuckle walkers. Knuckle walkers (Pan and Gorilla) have relatively little curvature of the middle phalanges coupled with marked curvature of the proximal phalanges, whereas brachiators (Ateles and Hylobates) display marked curvature of both proximal and middle phalanges, and pronograde quadrupeds (Cebus and Macaca) have relatively straight proximal and moderately curved middle phalanges. Quadrumanous climbers (Pongo) have a unique combination of traits, whereby curvature is high in both proximal and middle phalanges, but less so in the latter than the former. These differences, predictable on the basis of the biomechanical forces to which digits are subjected, may open a new venue for future research on the locomotor repertoire of prebipedal ancestors of hominins.  相似文献   
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IntroductionMuscle injury is common among athletes and amateur practitioners of sports. Following an injury, the production of reactive oxygen species (ROS) occurs, which can harm healthy muscle fibers (secondary damage) and delay the repair process. Low-level laser therapy (LLLT) administered prior to or following an injury has demonstrated positive and protective effects on muscle repair, but the combination of both administration times together has not been clarified.AimTo evaluate the effect of LLLT (660 nm and 780 nm, 10 J/cm², 40 mW, 3.2 J) prior to injury with or without the administration after injury on oxidative stress during the muscle repair process.MethodsWistar rats were divided into following groups: control; muscle injury alone; LLLT 660 nm + injury; LLLT 780 nm + injury; LLLT 660 nm before and after injury; and LLLT 780 nm before and after injury. The rats were euthanized on days 1, 3 and 7 following cryoinjury of the tibialis anterior (TA) muscle, which was then removed for analysis.ResultsLipid peroxidation decreased in the 660+injury group after one day. Moreover, red and infrared LLLT employed at both administration times induced a decrease in lipid peroxidation after seven days. CAT activity was altered by LLLT in all periods evaluated, with a decrease after one day in the 780+injury+780 group and after seven days in the 780+injury group as well as an increase in the 780+injury and 780+injury+780 groups after three days. Furthermore, increases in GPx and SOD activity were found after seven days in the 780+injury+780 group.ConclusionThe administration of red and infrared laser therapy at different times positively modulates the activity of antioxidant enzymes and reduces stress markers during the muscle repair process.  相似文献   
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Purpose

This study aims at comparing, from an environmental point of view, four different scenarios of freight transport at the Italian level, on an equal base of route between supplier and customer. The first scenario included freight movements by truck and mainly ship, the second included track and mainly train, the third was the three-modal based scenario, whilst the fourth scenario was the only uni-modal, based only upon truck movement.

The study was conducted to find the environmentally sustainable solution, or at least a sustainable trade-off, as well as the most environmentally burdening issues, associated with the geographic dimension of transport in Italy, towards sustainability.

Methods

Using uni‐ and multi-modal freight movements by truck, rail and ship, a life cycle assessment (LCA) was developed to estimate the related environmental burdens both at the midpoint and at the endpoint levels from the consumption of primary energy and natural resources along with the emissions of greenhouse gases (GHGs) and of other pollutants. Primary data were compiled as part of the inventory analysis and consisted in the transport flows associated with the system investigated: those were calculated from the distance travelled and the goods load transported. Primary data were then combined with secondary data that were modelled with the transport life cycle modules contained in Ecoinvent: from those modules, the fuel consumption amounts associated transport flows were extrapolated, and used for the assessment.

Results

Results showed that the environmental impact of the multi-modal scenarios is lower compared with the uni-modal scenario. The best performing option was found to be the third scenario providing use of all the three freight means, namely ship, train and truck. However, this scenario is not being practiced for several reasons, mainly due to control and monitoring difficulties of each step and higher operational costs. The first and second scenarios showed a quite comparable environmental behaviour and so are to be considered as viable options.

Conclusions

Apart from highlighting the most environmentally viable transport options, the study contributed to finding the indicators of environmental impact and damage that best describe the system investigated and are recommended by this author team to be accounted for in future assessments in the transport sector. Finally, although site-specific, the results of this study may be useful to logistics companies, policy and decision makers of other regions and countries towards identifying and promoting environmentally optimal freight transport solutions, contributing to sustainability of the transport sector.

  相似文献   
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Human olfactory receptor, hOR17-210, is identified as a pseudogene in the human genome. Experimental data has shown however, that the gene product of frame-shifted, cloned hOR17-210 cDNA was able to bind an odorant-binding protein and is narrowly tuned for excitation by cyclic ketones. Supported by experimental results, we used the bioinformatics methods of sequence analysis (genome-wide and pair-wise), computational protein modeling and docking, to show that functionality in this receptor is retained due to sequence-structure features not previously observed in mammalian ORs. This receptor does not possess the first two transmembrane helical domains (of seven typically seen in GPCRs). It however, possesses an additional TM that has not been observed in other human olfactory receptors. By incorporating these novel structural features, we created two putative models for this receptor. We also docked odor ligands that were experimentally shown to bind hOR17-210. We show how and why structural modifications of OR17-210 do not hinder this receptor's functionality. Our studies reveal that novel gene rearrangements that result in sequence and structural diversity may have a bearing on OR and GPCR function and evolution.  相似文献   
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DNA methylation 40 years later: Its role in human health and disease   总被引:4,自引:0,他引:4  
A long path, initiated more than 40 years ago, has led to a deeper understanding of the complexity of gene regulation in eukaryotic genomes. In addition to genetic mechanisms, the imbalance in the epigenetic control of gene expression may profoundly alter the finely tuned machinery leading to gene regulation. Here, we review the impact of the studies on DNA methylation, the "primadonna" in the epigenetic scenario, on the understanding of basic phenomena, such as X inactivation and genomic imprinting. The effect of deregulation of DNA methylation on human health, will be also discussed. Finally, an attempt to predict future directions of this rapidly evolving field has been proposed, with the certainty that, fortunately, science is always better than predictions.  相似文献   
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