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1.
B. Jáuregui M.C. de Vicente R. Messeguer A. Felipe A. Bonnet G. Salesses P. Arús 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(8):1169-1176
A map with 51 markers (46 RFLPs and five isozymes) was constructed using an interspecific F2 population between ’Garfi’ almond (Prunus amygdalus Batsch.) and ’Nemared’ peach [Prunus persica (L.) Batsch.]. This map was developed by selecting markers covering most of the distance of the eight linkage groups from
previously constructed Prunus maps. The markers studied in this population mapped to seven linkage groups instead of the eight expected in Prunus. Markers belonging to groups 6 and 8 in previous maps formed a single group in the ’Garfi’×’Nemared’ F2 and several marker pairs placed in different groups in other maps exhibited tight linkages. The study of pollen fertility
and chromosome behavior during meiosis in the F1 generation allowed us to confirm the hypothesis that a reciprocal translocation exists between ’Garfi’ and ’Nemared’. Based
on independent evidence of linkage between markers and pollen fertility data in the F2 population, we concluded that the breakpoint of the reciprocal translocation was placed between markers AC50 and AG26A in
group 6 and between markers AG112A and FG230A in group 8.
Received: 28 June 2000 / Accepted: 17 October 2000 相似文献
2.
Maltotriose is metabolized by baker’s and brewer’s yeast only oxidatively, with a respiratory quotient of 1.0, the
being, depending on the strain used, 0–11, as compared with
of 6–42μL CO2 per h per mg dry substance. The transport appeared to proceed by facilitated diffusion (no effects of NaF, iodoacetamide
and 3-chlorophenylhydrazonomalononitrile) with a KT of more than 50mm and was inhibited by maltose > maltotriose > methyl-α-D-glucoside > maltotetraose >D-fruetose >D-glucose. The transport was present constitutively in bothSaccharomyces cerevisiae (baker’s yeast) and inS. uvarum (brewer’s yeast) and it was not significantly stimulated by preincubation with glucose or maltose. The pH optimum was 4.5–5.5,
the temperature dependence yielded an activation energy of 26 kJ/mol. 相似文献
3.
The objective of this paper is the structural and narrative reconstruction of representations of ‘nature’, ‘wildlife’ and
‘landscape’, held by rural residents of the Dadia Forest Reserve. Data collection involved in-depth interviews. Employing
a social representations’ approach, we recovered representational elements that are expected in the case of rural belief systems,
such as negative dispositions towards wolves and foxes, as well as elements of an urban adherence, such as nature’s independence.
Representational elements refer to visual aspects of the countryside, which seem compatible with the figurative nucleus of
the rural idyll. Concerning ‘wildlife’, residents focused on vultures, which comprise the main tourist attraction of the reserve.
Scientific knowledge adds to the complexity of the narrative schema, which corresponds to the representation of ‘wildlife’.
Interviewees perceived the rural landscape as an interface between the natural and the human-conditioned environment. Our
study shows that interviewees make no reference to environmental conservation or quality of life issues, as it could be expected
according to relatively wide definitions of the term ‘environmentalism’. Environmental messages reinforced by ecotourism development
seem to be recalled primarily in terms of their compatibility with the perceived economic benefit of local people. Despite
ecotourism development, representational elements that diverge from a tourist version of ‘nature’, ‘wildlife’ and ‘landscape’
were not pronounced within rural belief-systems. Further interventions within the study area are needed, in order to address
a variety of topics under the environmental conservation discourse and raise the environmental awareness of rural residents. 相似文献
4.
Retinal neurodegeneration and visual dysfunctions have been reported in a majority of Alzheimer’s and Parkinson’s patients, and, in light of the quest for novel biomarkers for these neurodegenerative proteinopathies, the retina has been receiving increasing attention as an organ for diagnosing, monitoring, and understanding disease. Thinning of retinal layers, abnormalities in vasculature, and protein deposition can be imaged at unprecedented resolution, which offers a unique systems biology view on the cellular and molecular changes underlying these pathologies. It makes the retina not only a promising target for biomarker development, but it also suggests that novel fundamental insights into the pathophysiology of Alzheimer’s and Parkinson’s disease can be obtained by studying the retina–brain axis. 相似文献
5.
《Mutation Research/Genetic Toxicology》1983,116(3-4):323-331
Perchloroethylene (PCE) was tested in a diploid strain (D7) of the yeast Saccharomyces cerevisiae in suspension tests with and without a mammalian microsomal activation system (S9) and ‘in vivo’ by the intrasanguineous host-mediated assay. In addition, enzyme alteration studies were performed in mice non-pretreated or pretreated with phenobarbital + β-naphthoflavone. PCE did not induce any genetic effect either ‘in vitro’ or ‘in vivo’. In the suspension test, PCE was more toxic without metabolic activation and less toxic with mammalian microsomal activation. The enzymatic determinations showed an increase of the aminopyrine demethylase activity and of the level of cytochrome P-450. 相似文献
6.
Morgan Sheng Bernardo L. Sabatini Thomas C. Südhof 《Cold Spring Harbor perspectives in biology》2012,4(5)
Alzheimer’s disease (AD) is a major cause of dementia in the elderly. Pathologically, AD is characterized by the accumulation of insoluble aggregates of Aβ-peptides that are proteolytic cleavage products of the amyloid-β precursor protein (“plaques”) and by insoluble filaments composed of hyperphosphorylated tau protein (“tangles”). Familial forms of AD often display increased production of Aβ peptides and/or altered activity of presenilins, the catalytic subunits of γ-secretase that produce Aβ peptides. Although the pathogenesis of AD remains unclear, recent studies have highlighted two major themes that are likely important. First, oligomeric Aβ species have strong detrimental effects on synapse function and structure, particularly on the postsynaptic side. Second, decreased presenilin function impairs synaptic transmission and promotes neurodegeneration. The mechanisms underlying these processes are beginning to be elucidated, and, although their relevance to AD remains debated, understanding these processes will likely allow new therapeutic avenues to AD.Alzheimer’s disease (AD) is a common neurodegenerative disease of the elderly, first described by the physician-pathologist Alois Alzheimer in 1907 (Maurer and Maurer 2003). Clinically, AD is characterized by progressive impairment of memory (particularly short-term memory in early stages) and other cognitive disabilities, personality changes, and ultimately, complete dependence on others. The most prevalent cause of dementia worldwide, AD afflicts >5 million people in the United States and >25 million globally (Alzheimer’s Association, http://www.alz.org). Age is the most important risk factor, with the prevalence of AD rising exponentially after 65 (Blennow et al. 2006). However, many cases of so-called AD above 80 yr of age may result from a combination of pathological dementia processes (Fotuhi et al. 2009). The apolipoprotein E (ApoE) gene is the most important genetic susceptibility factor for AD, with the relatively common ApoE4 allele (prevalence ∼16%) increasing the risk for AD threefold to fourfold in heterozygous dose (Kim et al. 2009).The histopathological hallmarks of AD are amyloid plaques (extracellular deposits consisting largely of aggregated amyloid beta [Aβ] peptide that are typically surrounded by neurons with dystrophic neurites) and neurofibrillary tangles (NFTs, intracellular filamentous aggregates of hyperphosphorylated tau, a microtubule-binding protein) (Blennow et al. 2006). The development of amyloid plaques typically precedes clinically significant symptoms by at least 10–15 yr. Amyloid plaques are found in a minority of nondemented elderly patients, who may represent a “presymptomatic” AD population. As AD progresses, cognitive function worsens, synapse loss and neuronal cell death become prominent, and there is substantial reduction in brain volume, especially in the entorhinal cortex and hippocampus. The best correlation between dementia and histopathological changes is observed with neurofibrillary tangles, whereas the relationship between the density of amyloid plaques and loss of cognition is weaker (Braak and Braak 1990; Nagy et al. 1995). In addition to amyloid plaques and neurofibrillary tangles, many AD cases exhibit widespread Lewy body pathology. (Lewy bodies are intracellular inclusion bodies that contain aggregates of α-synuclein and other proteins.) Particularly in very old patients, considerable overlap between AD, frontotemporal dementia, Lewy body dementia, and vascular disease is observed, and pure AD may be rare (Fotuhi et al. 2009). 相似文献
7.
8.
Altered glutamatergic neurotransmission and neuronal metabolic dysfunction appear to be central to the pathophysiology of
Parkinson’s disease (PD). The substantia nigra pars compacta—the area where the primary pathological lesion is located—is
particularly exposed to oxidative stress and toxic and metabolic insults. A reduced capacity to cope with metabolic demands,
possibly related to impaired mitochondrial function, may render nigral neurons highly vulnerable to the effects of glutamate,
which acts as a neurotoxin in the presence of impaired cellular energy metabolism. In this way, glutamate may participate
in the pathogenesis of PD. Degeneration of dopamine nigral neurons is followed by striatal dopaminergic denervation, which
causes a cascade of functional modifications in the activity of basal ganglia nuclei. As an excitatory neurotransmitter, glutamate
plays a pivotal role in normal basal ganglia circuitry. With nigrostriatal dopaminergic depletion, the glutamatergic projections
from subthalamic nucleus to the basal ganglia output nuclei become overactive and there are regulatory changes in glutamate
receptors in these regions. There is also evidence of increased glutamatergic activity in the striatum. In animal models,
blockade of glutamate receptors ameliorates the motor manifestations of PD. Therefore, it appears that abnormal patterns of
glutamatergic neurotransmission are important in the symptoms of PD. The involvement of the glutamatergic system in the pathogenesis
and symptomatology of PD provides potential new targets for therapeutic intervention in this neuro-degenerative disorder. 相似文献
9.
Autophagy is an essential degradation pathway in clearing abnormal protein aggregates in mammalian cells and is responsible for protein homeostasis and neuronal health. Several studies have shown that autophagy deficits occurred in early stage of Alzheimer’s disease (AD). Autophagy plays an important role in generation and metabolism of β-amyloid (Aβ), assembling of tau and thus its malfunction may lead to the progress of AD. By considering the above evidences, autophagy may be a new target in developing drugs for AD. So far, a number of mammalian target of rapamycin (mTOR)-dependent and independent autophagy modulators have been identified to have positive effects in AD treatment. In this review, we summarized the latest progress supporting the role for autophagy deficits in AD and the potential therapeutic effects of autophagy modulators in AD. 相似文献
10.
Chronic oral anticoagulant treatment is obligatory in patients (class I) with mechanical heart valves and in patients with atrial fibrillation with CHADS2 score >1. When these patients undergo percutaneous coronary intervention with placement of a stent, there is also an indication for treatment with aspirin and clopidogrel. Unfortunately, triple therapy is known to increase the bleeding risk. For this group of patients, the bottom line is to find the ideal therapy in patients with indications for both chronic anticoagulation therapy and percutaneous intervention to prevent thromboembolic complications such as stent thrombosis without increasing the risk of bleeding. (Neth Heart J 2010;18:444-50.) 相似文献
11.
Daniele Daffonchio Francesca Mapelli Ameur Cherif Hanan I. Malkawi Michail M. Yakimov Yasser R. Abdel-Fattah Mohamed Blaghen Peter N. Golyshin Manuel Ferrer Nicolas Kalogerakis Nico Boon Mirko Magagnini Fabio Fava 《Reviews in Environmental Science and Biotechnology》2012,11(3):207-211
The civilizations in the Mediterranean Sea have deeply changed the local environment, especially with the extraction of subsurface oil and gas, their refinery and transportation. Major environmental impacts are affecting all the sides of the basin with actual and potential natural and socio-economic problems. Events like the recent BP??s oil disaster in the Gulf of Mexico would have a tremendous impact on a close basin like the Mediterranean Sea. The recently EU-funded project ULIXES (http://www.ulixes.unimi.it/) aims to unravel, categorize, catalogue, exploit and manage the microbial diversity available in the Mediterranean Sea for addressing bioremediation of polluted marine sites. The rationale of the project is based on the multiple diverse environmental niches of the Mediterranean Sea and the huge range of microorganisms inhabiting therein. Microbial consortia and their ecology, their components or products are used for designing novel pollutant- and site-tailored bioremediation approaches. ULIXES exploits microbial resource mining by the isolation of novel microorganisms as well as by novel advanced ??meta-omics?? technologies for solving pollution of three major high priority pollutant classes, petroleum hydrocarbons, chlorinated compounds and heavy metals. A network of twelve European and Southern Mediterranean partners is exploring the microbial diversity and ecology associated to a large set of polluted environmental matrices including seashore sands, lagoons, harbors and deep-sea sediments, oil tanker shipwreck sites, as well as coastal and deep sea natural sites where hydrocarbon seepages occur. The mined collections are exploited for developing novel bioremediation processes to be tested in ex situ and in situ field bioremediation trials. 相似文献
12.
Metalloproteinase’s Activity and Oxidative Stress in Mild Cognitive Impairment and Alzheimer’s Disease 总被引:1,自引:0,他引:1
Martín-Aragón S Bermejo-Bescós P Benedí J Felici E Gil P Ribera JM Villar AM 《Neurochemical research》2009,34(2):373-378
Matrix metalloproteinases (MMPs) and oxidative stress have been implicated in neurological diseases such as Alzheimer’s disease
(AD). Plasma MMP-2 and MMP-9 activities were assessed in Mild Cognitive Impairment (MCI) and AD subjects compared with aged-matched
controls, and subsequently analysed in relation to oxidative stress markers. Both MMP-2 and MMP-9 showed no significant changes
versus control subjects. Plasma glutathione peroxidase Se-dependent (GPx-Se) activity and malondialdehyde (MDA) levels were
higher in AD than in controls (P < 0.05), suggesting a role for GPx-Se in controlling oxidative stress in AD. Negative correlations were observed between MMPs
and MDA in AD and MCI patients (P < 0.05). In conclusion, oxidative stress events did not include activation of MMPs and this similar pattern in AD and MCI
suggests that both are biochemically equivalent. 相似文献
13.
Mapping of four major rice blast resistance genes from ’Lemont’ and ’Teqing’ and evaluation of their combinatorial effect for field resistance 总被引:1,自引:0,他引:1
R. E. Tabien Z. Li A. H. Paterson M. A. Marchetti J. W. Stansel S. R. M. Pinson W. D. Park 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(8):1215-1225
A framework linkage map was developed using 284 F10 recombinant inbred lines (RILs) from a ’Lemont’×’Teqing’ rice cultivar cross. Evaluation of a subset of 245 of these RILs
with five races of the rice blast pathogen permitted RFLP mapping of three major resistance genes from Teqing and one major
gene from Lemont. All mapped genes were found to confer resistance to at least two blast races, but none conferred resistance
to all five races evaluated. RFLP mapping showed that the three resistance genes from Teqing, designated Pi-tq5, Pi-tq1 and Pi-tq6, were present on chromosomes 2, 6 and 12, respectively. The resistance gene from Lemont, Pi-lm2, was located on chromosome 11. Pi-tq1 is considered a new gene, based on its reaction to these five races and its unique map location, while the other three genes
may be allelic with previously reported genes. Lines with different gene combinations were evaluated for disease reaction
in field plots. Some gene combinations showed both direct effects and non-linear interaction. The fact that some of the lines
without any of the four tagged genes exhibited useful levels of resistance in the field plots suggests the presence of additional
genes or QTLs affecting the blast reaction segregating in this population.
Received: 16 December 1999 / Accepted: 28 February 2000 相似文献
14.
15.
David E. Kime 《Reviews in Fish Biology and Fisheries》1993,3(2):160-180
Summary The nature of the steroids secreted by gonads of fish differs significantly from those of the mammals. The classical teleost steroids, oestradiol, testosterone, 11-ketotestosterone and 17,20P, have been measured in a wide variety of teleosts but do not always reflect biological activities. There is increasing evidence that teleost gonads may produce a number of non-classical steroids which may play an important role in their reproductive biology. Such products include metabolites reduced at C5 to 5 or 5, at C3 to 3 or 3, or hydroxylated at 6-, 7-, or 21. Conjugation, as either glucuronides or sulphates, may contribute either to localization of action within the gonad or to production of pheromones during the immediate pre-spawning period. Although it is often possible only to measure the steroids for which assays are readily available, it is important to recognize that there may be production of steroids that are not detected by such assays, but which nevertheless play a major role in reproductive activity. In evolutionary terms, the teleost hydroxylases probably originated in the very early fishes and show parallels with their analogues in amphibians and mammals. Gene sequencing may reveal a possible common ancestor for all vertebrate 6, 7 and 11-hydroxylases. 相似文献
16.
Amy E. Lerman 《Ethnic and racial studies》2014,37(10):1739-1746
In this short response to Loïc Wacquant's ‘Marginality, Ethnicity and Penality in the Neo-liberal City’, I outline two intellectual conversations that emerge from the author's work. The first develops out of the connections that the author draws between systems of criminal justice and welfare. The second grows out of the disassociation he urges us to see between the logics and trajectories of crime, on the one hand, and criminal justice on the other. I then briefly describe how my own work has been influenced by and contributes to these two ongoing streams of research. 相似文献
17.
Chasing genes in Alzheimer’s and Parkinson’s disease 总被引:4,自引:0,他引:4
Alzheimers disease (AD), the most common type of dementia, and Parkinsons disease (PD), the most common movement disorder, are both neurodegenerative adult-onset diseases characterized by the progressive loss of specific neuronal populations and the accumulation of intraneuronal inclusions. The search for genetic and environmental factors that determine the fate of neurons during the ageing process has been a widespread approach in the battle against neurodegenerative disorders. Genetic studies of AD and PD initially focused on the search for genes involved in the aetiological mechanisms of monogenic forms of these diseases. They later expanded to study hundreds of patients, affected relative-pairs and population-based studies, sometimes performed on special isolated populations. A growing number of genes (and pathogenic mutations) is being identified that cause or increase susceptibility to AD and PD. This review discusses the way in which strategies of gene hunting have evolved during the last few years and the significance of finding genes such as the presenilins, -synuclein, parkin and DJ-1. In addition, we discuss possible links between these two neurodegenerative disorders. The clinical, pathological and genetic presentation of AD and PD suggests the involvement of a few overlapping interrelated pathways. Their imbricate features point to a spectrum of neurodegeneration (tauopathies, synucleinopathies, amyloidopathies) that need further intense investigation to find the missing links. 相似文献
18.
We examined the degree to which civic learning activities and civic discussion in the classroom were associated with children’s civic engagement in the upper elementary grades. We also explored the types of civic activities used by teachers during middle childhood. Survey data were collected from 359 ethnically and economically diverse 4th–6th grade students (M age?=?10.56, 56% female), their parents, and teachers (n?=?20) from six public schools in Southern California. The results of path analyses showed that teachers’ greater use of civic learning activities was associated with higher levels of social responsibility to people and civic values in students. However, general civic discussion was not associated with any indicators of children’s civic engagement. Additionally, teachers reported using numerous types of civic activities, thus showing the diversity in “civic learning” across classrooms. Practical implications for elementary civic education are discussed. 相似文献
19.
Gabriele Alex 《Ethnos》2013,78(4):523-543
In India, touch is a prime marker of status and social relations. Those who are impure are ‘untouchable’,1 but those who are of a relatively higher purity are also, depending on the context, either ‘untouchable’ or ‘touchable’ only under certain fixed rules. In this paper, I will explore the contexts in which body contact and touch can be part of personal relations. I describe how these body contacts signify important social relations and establish community identity. Further, I will analyse how patterns of body contact on the one hand change during childhood, and on the other hand produce changes in the status of a social persona. The last point to be investigated is the meaning of touch as a sign for public representations. 相似文献
20.
Cooperation towards public goods relies on credible threats of punishment to deter cheats. However, punishing is costly, so
it remains unclear who incurred the costs of enforcement in our evolutionary past. Theoretical work suggests that human cooperation
may be promoted if people believe in supernatural punishment for moral transgressions. This theory is supported by new work in cognitive psychology and by anecdotal ethnographic
evidence, but formal quantitative tests remain to be done. Using data from 186 societies around the globe, I test whether
the likelihood of supernatural punishment—indexed by the importance of moralizing “high gods”—is associated with cooperation.
Dominic Johnson is a fellow in the Princeton University Society of Fellows. He holds a D.Phil. in biology from Oxford University
and a Ph.D. in political science from Geneva University. His research revolves around the evolutionary biology of human behavior
and how this impacts on conflict, cooperation, politics, and religion. His recent book, Overconfidence and War: The Havoc and Glory of Positive Illusions, was published in 2004 by Harvard University Press. 相似文献