共查询到20条相似文献,搜索用时 31 毫秒
1.
zur Hausen H 《Biochemistry. Biokhimii?a》2008,73(5):498-503
High risk human papillomavirus (HPV) types 16 and 18 DNAs were initially identified in 1983-1984. Subsequently the DNA of several other high risk HPV types has been identified. HPV 16 is present in more than 50% of cervical cancer biopsies, and HPV 18 is close to 20%. Some geographic variations exist in the prevalence of HPV high risk types: e.g. HPV 45 is more frequently observed in equatorial Africa, whereas types 58 and 52 have been more often found in East Asia. Molecular as well as epidemiological studies demonstrate that high risk HPV are indeed the causative agents for cervical cancer, they are also involved in other anogenital cancers, and in 25-30% of oropharyngeal carcinomas. Some of the mechanistic aspects are discussed in this review. 相似文献
2.
In response to agriculture''s vulnerability and contribution to climate change, many governments are developing initiatives that promote the adoption of mitigation and adaptation practices among farmers. Since most climate policies affecting agriculture rely on voluntary efforts by individual farmers, success requires a sound understanding of the factors that motivate farmers to change practices. Recent evidence suggests that past experience with the effects of climate change and the psychological distance associated with people''s concern for global and local impacts can influence environmental behavior. Here we surveyed farmers in a representative rural county in California''s Central Valley to examine how their intention to adopt mitigation and adaptation practices is influenced by previous climate experiences and their global and local concerns about climate change. Perceived changes in water availability had significant effects on farmers'' intention to adopt mitigation and adaptation strategies, which were mediated through global and local concerns respectively. This suggests that mitigation is largely motivated by psychologically distant concerns and beliefs about climate change, while adaptation is driven by psychologically proximate concerns for local impacts. This match between attitudes and behaviors according to the psychological distance at which they are cognitively construed indicates that policy and outreach initiatives may benefit by framing climate impacts and behavioral goals concordantly; either in a global context for mitigation or a local context for adaptation. 相似文献
3.
4.
Chantal Deschamps Arnaud Echard Florence Niedergang 《Traffic (Copenhagen, Denmark)》2013,14(4):355-364
Eukaryotic cells with specialized functions often use and adapt common molecular machineries. Recent findings have highlighted that actin polymerization, contractile activity and membrane remodelling with exocytosis of internal compartments are required both for successful phagocytosis, the internalization of particulate material and for cytokinesis, the last step of cell division. Phagocytosis is induced by the triggering of specific cell surface receptors, which leads to membrane deformation, pseudopod extension and contraction to engulf particles. Cytokinesis relies on intense contractile activity and eventually leads to the physical scission of sister cells. In this review, shared features of signalling, cytoskeletal reorganization and vesicular trafficking used in both phagocytosis and cytokinesis will be described, but non‐common mechanisms and questions that remain open in these dynamic areas of research are also highlighted . 相似文献
5.
Malashichev YB Wassersug RJ 《BioEssays : news and reviews in molecular, cellular and developmental biology》2004,26(5):512-522
The last decade has seen a dramatic increase in studies on the development, function and evolution of asymmetries in vertebrates, including amphibians. Here we discuss current knowledge of behavioral and anatomical asymmetries in amphibians. Behavioral laterality in the response of both adult and larval anurans to presumed predators and competitors is strong and may be related, respectively, to laterality in the telencephalon of adults and the Mauthner neurons of tadpoles. These behavior lateralities, however, do not seem to correlate with visceral asymmetries in the same animals. We briefly compare what is known about the evolution and development of asymmetry in the structure and function of amphibians with what is known about asymmetries in other chordate and non-chordate groups. Available data suggest that the majority of asymmetries in amphibians fall into two independent groups: (1) related to situs viscerum and (2) of a neurobehavioral nature. We find little evidence linking these two groups, which implies different developmental regulatory pathways and independent evolutionary histories for visceral and telencephalic lateralizations. Studies of animals other than standard model species are essential to test hypotheses about the evolution of laterality in amphibians and other chordates. 相似文献
6.
7.
Plasma ANP (atrial natriuretic peptide), thyroid hormones, and calcium and magnesium levels as well as heart tissue calcium
and magnesium concentrations were determined in male Wistar rats after exposure of 114 rats at low temperature (4°C) and 95
rats at high temperature (35–36°C) for 28 d. Plasma ANP, triiodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH), free T3, and free T4 were estimated by radioimmunoassay, and plasma and heart tissue levels of Ca and Mg by flame atomic absorption spectrophotometry.
Results were compared to a control group exposed at 20–22°C (76 rats).
All the above parameters in control rats did not show statistically significant variations during the study. A significant
increase of plasma ANP, T3, T4, Ca, and Mg concentrations developed during cold exposure, whereas a gradual decrease of plasma ANP, T3, T4, and Mg concentrations was revealed during hot exposure. A significant increase of heart tissue Mg concentrations developed
during hot exposure. Results also indicate that plasma ANP and T3 levels are proportionally related, whereas an inverse relationship exists between plasma ANP and T3 levels and heart Mg concentrations, in both cold and hot exposed rats. In conclusion, ANP and thyroid hormones in relation
to Ca and Mg play an important role in temperature adaptation. 相似文献
8.
P.A.T. Martins 《生物化学与生物物理学报:生物膜》2008,1778(5):1308-1315
The bovine milk lipocalin, β-Lactoglobulin (β-LG), has been associated with the binding and transport of small hydrophobic and amphiphilic compounds, whereby it is proposed to increase their bioavailability. We have studied the binding of the fluorescent phospholipid-derivative, NBD-didecanoylphosphatidylethanolamine (NBD-diC10PE) to β-LG by following the increase in amphiphile fluorescence upon binding to the protein using established methods. The equilibrium association constant, KB, was (1.2 ± 0.2) × 106 M− 1 at 25 °C, pH 7.4 and I = 0.15 M. Dependence of KB on pH and on the monomer-dimer equilibrium of β-LG gave insight on the nature of the binding site which is proposed to be the hydrophobic calyx formed by the β-barrel in the protein. The monomer-dimer equilibrium of β-LG was re-assessed using fluorescence anisotropy of Tryptophan. The equilibrium constant for dimerization, KD, was (7.0 ± 1.5) × 105 M− 1 at 25 °C, pH 7.4, and 0.15 M ionic strength. The exchange of NBD-diC10PE between β-LG and POPC lipid bilayers was followed by the change in NBD fluorescence. β-LG was shown to be a catalyst of phospholipid exchange between lipid bilayers, the mechanism possibly involving adsorption of the protein at the bilayer surface. 相似文献
9.
Objectives
Single nucleotide polymorphisms (SNPs), genetic background, and epigenetics play important roles in rheumatoid arthritis (RA). These factors can be useful in RA diagnosis, prognosis, and treatment response evaluation, particularly with the growing trends in personalized medicine. Therefore, categorizing classic genes and SNPs in RA can present an appropriate guideline for RA management.Discussion
Prognostic and diagnostic biomarkers play important roles in RA diagnosis and treatment. Categorizing SNPs is not an easy process yet, but selecting classic SNPs can be useful worldwide, according to basic similarities that exist in genomes. In this review, we compiled some of these RA-associated SNPs and biomarkers in a table, according to newly identified factors. The role of epigenetics in RA is undeniable; using epigenetic biomarkers like histone deacetylase (HDACs) can be useful in RA diagnosis and treatment. miRs such as miR-146a, miR-155, and miR-222 are useful in diagnosis and can be used in treatment by interfering with other factors’ functions. Interleukins (ILs) seem to be good prognostic and diagnostic markers and can be targeted in RA treatment.Conclusion
Using multiple types of biomarkers, such as genes, SNPs, and epigenetic biomarkers like HDACs can be useful in RA management and treatment. PTPN22, HLA-DR polymorphisms, miRs, and HDACs are considerable in RA susceptibility; hence, they can be valuable biomarkers in future studies. This article gathered separate information from approximately 100 articles to present useful biomarkers and polymorphisms in one review.10.
Carbonari Caio A. Latorre Débora O. Gomes Giovanna L. G. C. Velini Edivaldo D. Owens Daniel K. Pan Zhiqiang Dayan Franck E. 《Planta》2016,243(4):925-933
Planta - Insertion of the gene encoding phosphinothricin acetyltransferase (PAT) has resulted in cotton plants resistant to the herbicide glufosinate. However, the lower expression and commensurate... 相似文献
11.
Species richness in vascular plants was related to the plants’ calcifuge or calcicole behaviour using documentation from forests
and open-land vegetation at about one thousand sites in the southern parts of Sweden. It is concluded that vegetation of strongly
acid soils (pH-KCl < 4.5) have fewer vascular plant species than comparable vegetation of other soils, whereas there are no
consistent differences in species richness between slightly-moderately acid and calcareous sites. Low species richness is
particularly related to high concentrations of Al3+ and H+ ions (either soil solution concentrations or concentrations of exchangeable ions), not to a lack of calcium carbonate. The
majority of plant species are able to render the sparingly soluble phosphate, iron and manganese compounds of high-pH soils
available, but they are unable to tolerate much Al3+ or H+. Acidicole (calcifuge) species have developed the power of tolerating Al3+ and H+, which may be considered a secondary property of plants, but they have lost the power of solubilizing critical mineral nutrients
in high-pH soils. The reasons why these ecophysiological properties are inversely related in the current flora are obscure,
difficult to account for experimentally and a main ecological problem. In areas with cool-temperate climates the flora was
partly or mainly extinguished by the Pleistocene glaciations. Comparatively fewer calcifuge than calcicole species have, since
then, had enough time to develop, and the number of calcifuges is lower, in spite of the fact that most natural and seminatural
soils of these areas are nowadays acidic. 相似文献
12.
Wolf U. Blanckenhorn Richard F. Preziosi Daphne J. Fairbairn 《Evolutionary ecology》1995,9(4):369-381
Summary We present an empirical test of the Ghiselin—Reiss small-male hypothesis for the evolution of sexual size dimorphism (SSD). In mating systems dominated by scramble competition, where male reproductive success is a function of encounter rate with females, small males may be favoured when food is limiting because they require lower absolute amounts of food. Given a trade-off between time and energy devoted to foraging and to mate acquisition, small males should be able to devote more time to the latter. If at the same time larger females are favoured, this mechanism will contribute to the evolution of SSD and may be the major determinant of the female-biased SSDs that characterize most animal taxa. We tested this hypothesis using the water strider,Aquarius remigis (Heteroptera: Gerridae), a scramble competitor which mates many times over a prolonged mating season and which shows female-biased SSD. Laboratory experiments demonstrated that foraging success and giving up times (GUTs) are lower for males than for females during the reproductive season and that male water striders flexibly alter their time budgets under conditions of energy limitation. Controlled feeding experiments showed that male and female longevity, female fecundity and male mating success are positively related to food availability. As predicted, male body size is negatively correlated with several indices of male fitness (longevity, number of mating attempts and mating success), while female body size is positively correlated with longevity. These results are consistent with the hypothesis that scramble competition for mates favours small males in this species and provides empirical support for the Ghiselin—Reiss small-male hypothesis. 相似文献
13.
14.
15.
Whatever happened to the pyrenomycetes and loculoascomycetes? 总被引:3,自引:2,他引:1
16.
A forthcoming article in Nature reveals that inflammasome deficiency disturbs gut microbiota and predisposes to diet-induced obesity and liver disease. The aberrant microbiota and its consequences could be transferred by cohousing mutant and wild-type mice, suggesting that some aspects of metabolic syndrome can be communicable (Henao-Mejia et?al., 2012). 相似文献
17.
Background
The progression of cancer through stages that guide a benign hyperplastic epithelial tissue towards a fully malignant and metastatic carcinoma, is driven by genetic and microenvironmental factors that remodel the tissue architecture. The concept of epithelial–mesenchymal transition (EMT) has evolved to emphasize the importance of plastic changes in tissue architecture, and the cross-communication of tumor cells with various cells in the stroma and with specific molecules in the extracellular matrix (ECM).Scope of the review
Among the multitude of ECM-embedded cytokines and the regulatory potential of ECM molecules, this article focuses on the cytokine transforming growth factor β (TGFβ) and the glycosaminoglycan hyaluronan, and their roles in cancer biology and EMT. For brevity, we concentrate our effort on breast cancer.Major conclusions
Both normal and abnormal TGFβ signaling can be detected in carcinoma and stromal cells, and TGFβ-induced EMT requires the expression of hyaluronan synthase 2 (HAS2). Correspondingly, hyaluronan is a major constituent of tumor ECM and aberrant levels of both hyaluronan and TGFβ are thought to promote a wounding reaction to the local tissue homeostasis. The link between EMT and metastasis also involves the mesenchymal–epithelial transition (MET). ECM components, signaling networks, regulatory non-coding RNAs and epigenetic mechanisms form the network of regulation during EMT-MET.General significance
Understanding the mechanism that controls epithelial plasticity in the mammary gland promises the development of valuable biomarkers for the prognosis of breast cancer progression and even provides new ideas for a more integrative therapeutic approach against disease. This article is part of a Special Issue entitled Matrix-mediated cell behaviour and properties. 相似文献18.
Membrane translocation is a crucial issue when addressing the activity of both cell-penetrating and antimicrobial peptides. Translocation is responsible for the therapeutic potential of cell-penetrating peptides as drug carriers and can dictate the killing mechanisms, selectivity and efficiency of antimicrobial peptides. It is essential to evaluate if the internalization of cell-penetrating peptides is mediated by endocytosis and if it is able to internalize attached cargoes. The mode of action of an antimicrobial peptide cannot be fully understood if it is not known whether the peptide acts exclusively at the membrane level or also at the cytoplasm. Therefore, experimental methods to evaluate and quantify translocation processes are of first importance. In this work, over 20 methods described in the literature for the assessment of peptide translocation in vivo and in vitro, with and without attached macromolecular cargoes, are discussed and their applicability, advantages and disadvantages reviewed. In addition, a classification of these methods is proposed, based on common approaches to detect translocation. 相似文献
19.
20.
Seifried HE 《The Journal of nutritional biochemistry》2007,18(3):168-171
The thrust of this presentation takes a more programmatic approach and gives an overview of the programs at the NIH and the NCI that have a broad nutritional and basic science undercurrent and outline. Also discussed briefly are some areas of general concern that are under investigation in the nutrition group and are included in the group's outreach efforts among professional and academic organizations. The overarching focus of these efforts is to stress the importance of nutrition as a potential modulator of health/disease risks associated with genetic predisposition and environmentally induced disease from diet, lifestyle and exposure to pollutants. 相似文献