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1.
A high concentration of vanadium (V) has toxic effects on human and animals and is one of environmental pollutants. In the present study, we have conducted a fundamental study using cultured Vero cells from monkey kidney for the future environmental monitoring. Orthovanadate (VAN), one of V compounds, of 10−10 and 10−8 M did not affect the cell growth although the higher concentration of above 10−6 M VAN inhibited the cell growth accompanied with the decrease in cell numbers and morphological changes. Given that the washing method with ice-cold Li is also effective for determination of the cellular Na content, we used this method for the determination of the V content of the Vero cells. The V distributions in Vero cell; in the 10−3 M VAN solution, extracellular and intracellular were obtained as 1:0.564:0.036 and 1:0.662:0.098 at 60 and 120 min after the treatment of VAN. The intracellular V content was 10% of the applied concentration of VAN. Consequently, it was suggested that V concentration of 10−7 and 10−6 M in the tissue and environment, respectively, might become the threshold concentration; a criterion of the environmental contamination when we carry out environmental monitoring.  相似文献   

2.
Ulrich Demmer 《Ethnos》2015,80(1):91-116
This paper explores an understanding of the person in terms of practical reason. Based on my fieldwork among the Jenu Kurumba and on ethnographic data on four other communities, I analyse how these five communities conceptualise the ethical person. To understand these concepts, I consult studies of an anthropology of ethics concerned with practical reason. Additionally I draw on Charles Taylor's concept of the ‘agent plus’ and Alasdair MacIntyre's notion of the ‘practical reasoner’. I argue that both Neo-Aristotelian notions are fundamentally important for understanding the concepts of the ethical person among the five cultural formations investigated in this paper.  相似文献   

3.

Background

Of the putative psychopathological endophenotypes in major depressive disorder (MDD), the anhedonic subtype is particularly well supported. Anhedonia is generally assumed to reflect aberrant motivation and reward responsivity. However, research has been limited by a lack of objective measures of reward motivation. We present the Effort-Expenditure for Rewards Task (EEfRT or “effort”), a novel behavioral paradigm as a means of exploring effort-based decision-making in humans. Using the EEfRT, we test the hypothesis that effort-based decision-making is related to trait anhedonia.

Methods/Results

61 undergraduate students participated in the experiment. Subjects completed self-report measures of mood and trait anhedonia, and completed the EEfRT. Across multiple analyses, we found a significant inverse relationship between anhedonia and willingness to expend effort for rewards.

Conclusions

These findings suggest that anhedonia is specifically associated with decreased motivation for rewards, and provide initial validation for the EEfRT as a laboratory-based behavioral measure of reward motivation and effort-based decision-making in humans.  相似文献   

4.

Background

Research on the temporal relationship of parental risk factors with offspring’s suicide attempt is scarce and a life course approach has not been applied to date. We investigated the temporal relationship of parental morbidity and mortality with offspring’s suicide attempt and whether any such association was modified by offspring’s age at attempt.

Methods

We designed a case-control study through linkage of Swedish registers. Cases comprised all individuals in Sweden born 1973–1983 with inpatient care due to suicide attempt (15–31 years of age) and with information on both biological parents (N = 15 193). Ten controls were matched to each case (National Patient register with national complete coverage). Conditional logistic and spline regressions were applied.

Results

Particularly for women, most parental markers showed the strongest effect sizes if exposure was short-term (within 2 years after exposure) and related to the mother. Especially short-term exposure to maternal inpatient care due to psychiatric diagnoses had a significantly stronger effect on suicide attempt risk in women compared to men. Regarding exposure to parental inpatient care due to psychiatric diagnoses, short-term as opposed to long-term (exceeding 2 years after exposure) effects were highest during adolescence and decreased significantly with age for female and male offspring, respectively.

Conclusions

Although limited by the fact that data on parental morbidity and the outcome of suicidality were based on in-patient data only, the data suggest that the high risks of suicide attempt in case of exposure to parental psychopathology and suicidal behavior particularly during adolescence and the strong short-term effects associated with maternal psychopathology for female offspring are of direct clinical importance.  相似文献   

5.
6.
F. A. Fattah 《Plant and Soil》1988,109(2):195-198
Wheat,Triticum aestivum L. cv. Mexipak was artificially inoculated withAnguina tritici (Steinb.) under field conditions. Nematode inocula: 0, 0.1, 0.2 and 0.3 g of seed galls/50 seeds or, germinated seeds of wheat (sown in a 1-m long row) were either added as intact seed galls or as a suspension of 2nd stage juveniles. Inoculation of ungerminated seeds with juveniles produced the highest incidence of ear-cockle disease. Whereas, intact seed galls inocula produced the highest incidence of tundu disease. Ear-cockle incidence was always greater than that of tundu at all treatments. The highest reduction in grain yield was associated with the treatments that caused the highest incidence of tundu disease.  相似文献   

7.
Systems biology is a new and rapidly developing research area in which, by quantitatively describing the interaction among all the individual components of a cell, a systems-level understanding of a biological response can be achieved. Therefore, it requires high-throughput measurement technologies for biological molecules, such as genomic and proteomic approaches for DNA/RNA and protein, respectively.Recently, a new concept, lipidomics, which utilizes the mass spectrometry (MS) method for lipid analysis,has been proposed. Using this lipidomic approach, the effects of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) on sphingomyelin metabolism, a major class of sphingolipids, were evaluated. Sphingomyelin molecules were extracted from cells and analyzed by matrix-assisted laser desorption ionization-time of flight MS. It was found that MNNG induced profound changes in sphingomyelin metabolism, including the appearance of some new sphingomyelin species and the disappearance of some others, and the concentrations of several sphingomyelin species also changed. This was accompanied by the redistribution of acid sphingomyelinase (ASM), a key player in sphingomyelin metabolism. On the other hand, imipramine, an inhibitor of ASM,caused the accumulation of sphingomyelin. It also prevented some of the effects of MNNG, as well as the redistribution of ASM. Taken together, these data suggested that the lipidomic approach is highly effective for the systematic analysis of cellular lipids metabolism.  相似文献   

8.
Systems biology is a new and rapidly developing research area in which,by quantitativelydescribing the interaction among all the individual components of a cell,a systems-level understanding of abiological response can be achieved.Therefore,it requires high-throughput measurement technologies forbiological molecules,such as genomic and proteomic approaches for DNA/RNA and protein,respectively.Recently,a new concept,lipidomics,which utilizes the mass spectrometry(MS)method for lipid analysis,has been proposed.Using this lipidomic approach,the effects of N-methyl-N'-nitro-N-nitrosoguanidine(MNNG)on sphingomyelin metabolism,a major class of sphingolipids,were evaluated.Sphingomyelin moleculeswere extracted from cells and analyzed by matrix-assisted laser desorption ionization-time of flight MS.Itwas found that MNNG induced profound changes in sphingomyelin metabolism,including the appearance ofsome new sphingomyelin species and the disappearance of some others,and the concentrations of severalsphmgomyelin species also changed.This was accompanied by the redistribution of acid sphingomyelinase(ASM),a key player in sphingomyelin metabolism.On the other hand,imipramine,an inhibitor of ASM,caused the accumulation of sphingomyelin.It also prevented some of the effects of MNNG,as well as theredistribution of ASM.Taken together,these data suggested that the lipidomic approach is highly effectivefor the systematic analysis of cellular lipids metabolism.  相似文献   

9.
During the past few decades radiation research has developed into specialized sub-disciplines, ranging from basic physics and chemistry to tumor biology and experimental radiotherapy. Scientific issues as well as the techniques and methodologies applied are subject to diverging discussion. The annual scientific meetings of the German ”Gesellschaft für Biologische Strahlenfor-schung (GBS)” were established with the primary aim of allowing up-to-date transfer of current knowledge in any of the topics in radiation research and of promoting interaction between different research groups. This report provides a summary of the presentations at the third annual meeting which took place in 1999 in Dresden, Germany. The meeting particularly focussed on frontline research in radiation chemistry, modeling of radiation effects, dosimetry of non-ionizing radiation and unconventional radiation qualities, e.g., heavy ions or soft x-rays, stochastic radiation effects, DNA repair, and various aspects of radiobiological research of cells, normal tissues and tumors. Received: 3 February 2000 / Accepted: 10 May 2000  相似文献   

10.
Biophysics - The results of calorimetric studies of a histological preparation of a surgically excised Baker’s cyst are presented. The measurements were performed on a DSC 204 F1 Phoenix...  相似文献   

11.
The pathogenesis of Alzheimer’s disease (AD) is associated with the aggregation of amyloid-β (Aβ) peptides into toxic aggregates with β-sheet character. In a previous computational study, we showed that pristine single-walled carbon nanotubes (SWCNTs) can inhibit the formation of β-sheet-rich oligomers in the central hydrophobic core fragment of Aβ (Aβ16–22). However, the poor solubility of SWCNTs in water hinders their use in biomedical applications and nanomedicine. Here, we investigate the influence of hydroxylated SWCNT, a water-soluble SWCNT derivative, on the aggregation of Aβ16–22 peptides using all-atom explicit-water replica exchange molecular dynamics simulations. Our results show that hydroxylated SWCNTs can significantly inhibit β-sheet formation and shift the conformations of Aβ16–22 oligomers from ordered β-sheet-rich structures toward disordered coil aggregates. Detailed analyses of the SWCNT-Aβ interaction reveal that the inhibition of β-sheet formation by hydroxylated SWCNTs mainly results from strong electrostatic interactions between the hydroxyl groups of SWCNTs and the positively charged residue K16 of Aβ16–22 and hydrophobic and aromatic stacking interactions between SWCNTs and F19 and F20. In addition, our atomic force microscopy and thioflavin T fluorescence experiments confirm the inhibitory effect of both pristine and hydroxylated SWCNTs on Aβ16–22 fibrillization, in support of our previous and present replica exchange molecular dynamics simulation results. These results demonstrate that hydroxylated SWCNTs efficiently inhibit the aggregation of Aβ16–22; in addition, they offer molecular insight into the inhibition mechanism, thus providing new clues for the design of therapeutic drugs against amyloidosis.  相似文献   

12.

Introduction

Studies have shown that depression or anxiety occur in 10–20% of pregnant women. These disorders are often undertreated and may affect mothers and children’s health. This study investigates the relation between antenatal maternal depression, anxiety and children’s early cognitive development among 1380 two-year-old children and 1227 three-year-old children.

Methods

In the French EDEN Mother-Child Cohort Study, language ability was assessed with the Communicative Development Inventory at 2 years of age and overall development with the Ages and Stages Questionnaire at 3 years of age. Multiple regressions and structural equation modeling were used to examine links between depression, anxiety during pregnancy and child cognitive development.

Results

We found strong significant associations between maternal antenatal anxiety and poorer children’s cognitive development at 2 and 3 years. Antenatal maternal depression was not associated with child development, except when antenatal maternal anxiety was also present. Both postnatal maternal depression and parental stimulation appeared to play mediating roles in the relation between antenatal maternal anxiety and children’s cognitive development. At 3 years, parental stimulation mediated 13.2% of the effect of antenatal maternal anxiety while postnatal maternal depression mediated 26.5%.

Discussion

The partial nature of these effects suggests that other mediators may play a role. Implications for theory and research on child development are discussed.  相似文献   

13.
Even though the incidence of pregnancies in the female recipients is lower and also chronic renal disease in male patients is associated with impaired spermatogenesis, the health of the children born to these patients was not studied. In this report, we discuss information on the growth and development of offspring of 248 male and female kidney recipient patients. Physical and routine clinical measurements of the 252 offspring (129 male and 123 female) born to these transplantation patients were made along with the intelligence tests. In some of these children chest X-ray and immune indices were assessed. Among the recipients, 219 males fathered 223 children with an average birth weight of 3,255 ± 374 g and 29 female recipients gave birth to 29 children with an average birth weight of 2,923 ± 551. While most of these children were normal, we noticed a case of soft double toe, a case of short tongue tie, five cases of marginal mental retardation, three cases of proteinuria, six cases of microscopic hematuria, 15 cases of low hemoglobin, and 21 cases with recurrent respiratory tract infections. We conclude that kidney transplantation has no significant impact on the growth, development, health, and intelligence of the offspring born to recipients.  相似文献   

14.
The skeletal record of tyrannosaurids is well-documented, whereas their footprint record is surprisingly sparse. There are only a few isolated footprints attributed to tyrannosaurids and, hitherto, no reported trackways. We report the world’s first trackways attributable to tyrannosaurids, and describe a new ichnotaxon attributable to tyrannosaurids. These trackways are from the Upper Cretaceous (Campanian - Maastrichtian) of northeastern British Columbia, Canada. One trackway consists of three tridactyl footprints, and two adjacent trackways consist of two footprints each. All three trackways show animals bearing southeast within an 8.5 meter-wide corridor. Similarities in depth and preservation of the tyrannosaurid tracks indicate that these three trackways were made by track-makers walking concurrently in the same direction. These trackways add significantly to previous osteology-based hypotheses of locomotion and behavior in Tyrannosauridae by providing ichnologic support for gregariousness in tyrannosaurids, and the first record of the walking gait of tyrannosaurids.  相似文献   

15.
Salt stress can suppress the immune function of fish and other aquatic animals, but such an effect has not yet been examined in air-breathing vertebrates that frequently cope with waters (and prey) of contrasting salinities. We investigated the effects of seawater salinity on the strength and cost of mounting an immune response in the dunlin Calidris alpina, a long-distance migratory shorebird that shifts seasonally from freshwater environments during the breeding season to marine environments during migration and the winter period. Phytohaemagglutinin (PHA)-induced skin swelling, basal metabolic rate (BMR), body mass, fat stores, and plasma ions were measured in dunlins acclimated to either freshwater or seawater (salinity: 0.3 and 35.0 ‰, respectively). Seawater-acclimated dunlins mounted a PHA-induced swelling response that was up to 56 % weaker than those held under freshwater conditions, despite ad libitum access to food. Freshwater-acclimated dunlins significantly increased their relative BMR 48 h after PHA injection, whereas seawater-acclimated dunlins did not. However, this differential immune and metabolic response between freshwater- and seawater-acclimated dunlins was not associated with significant changes in body mass, fat stores or plasma ions. Our results indicate that the strength of the immune response of this small-sized migratory shorebird was negatively influenced by the salinity of marine habitats. Further, these findings suggest that the reduced immune response observed under saline conditions might not be caused by an energy or nutrient limitation, and raise questions about the role of osmoregulatory hormones in the modulation of the immune system.  相似文献   

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19.
Scab resistance is one of the most important goals of apple breeding, typically achieved by time-consuming and expensive conventional breeding techniques. Cisgenesis, which is the genetic modification of a recipient organism with genes from a crossable—sexually compatible—organism, is a promising tool for plant breeding to develop disease resistance in a rapid way. A cisgenic, scab-resistant line of the apple variety ‘Gala’ expressing the native apple scab resistance gene Rvi6 (formerly HcrVf2) under control of its own regulatory sequences has been recently developed. In this paper, we present the results from a phenotypic, molecular and biochemical evaluation of clonal replicates of this line (C11.1.53). The phenotype (shoot length, shoot diameter, internode length, number of leaves, leaf length and leaf width) of C11.1.53 was compared to that of the Gala parental background over a period of 108 days. Only a few statistically significant differences were detected, which are probably due to small differences in the quality of the budwood used for grafting rather than effects related to the presence of the cisgene. As the expression of a resistance gene can affect the downstream cascade of plant defence responses, a selection of apple defence-related genes was analyzed by quantitative real-time PCR analysis. These genes are also known as major allergen genes in apple. Even if three out of ten apple allergen genes tested in the leaves differed in the cisgenic line compared to both Gala (background) and ‘Florina’ (the variety from which the Rvi6 gene was cloned), using 2D-PAGE, we were unable to find any significant difference in the expressed proteomes of the leaves of C11.1.53 compared to Gala. Results are discussed in the context of a possible use of cisgenic lines for fruit crop improvement.  相似文献   

20.
The combined effects of grazing and nutrient regeneration by Daphnia and Eudiaptomus on the growth of Rhodomonas and heterotrophic bacteria was assessed experimentally. The responses of Rhodomonas and bacteria to the grazers were measured as net specific growth rate over the entire experimental periods, as well as production and specific production at the end of the experiments. Both zooplankton species had a negative effect on Rhodomonas net specific growth rate due to grazing and a positive effect on specific primary production due to nutrient regeneration. Daphnia had no effect on bacterial net specific growth rate, bacterial production or specific bacterial production in one of two experiments. In the other experiment, however, both bacterial growth rate and production decreased as a result of grazing. Furthermore, Daphnia had a negative effect on specific bacterial production, but Eudiaptomus had a positive effect on all bacterial parameters due to nutrient regeneration, probably of phosphorus. Positive effects of copepods on bacterial growth has previously been attributed to trophic cascades via protozoa. However, the present experiments show that regeneration of nutrients, especially phosphorus, may account for a large part of the stimulation of bacterial growth.  相似文献   

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