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11.
Some carnation species (Dianthus spp., Caryophyllaceae) exhibit a strong resistance to drought stress that is connected with the increased surface wax formation. Wax composition is unknown for the majority of Dianthus spp. Herein, mass spectral and gas chromatographic data, in combination with synthesis and chemical transformations (transesterification and synthesis of dimethyl disulfide adducts), enabled the identification of 151 constituents of diethyl‐ether washings of fresh flowers of Dianthus cruentus Griseb . from Serbia. The flower wax contained, along with the dominant ubiquitous long‐chain n‐alkanes, homologous series of n‐ and branched (iso‐ and anteiso‐) long‐chain hexyl alkanoates/alkenoates and alkyl/alkenyl benzoates. The branching position in the mentioned hexyl esters was probed by synthesis of esters of three isomeric hexanols that were spectrally characterized (1H‐ and 13C‐NMR, IR, MS). The washings also contained long‐chain (Z)‐ and (E)‐alkenes (C23?C35) with several different double bond regiochemistries. Fifty‐five of these constituents (eight hexyl esters, two benzoates, and forty‐five alkenes) were detected for the first time in Plantae, while ten of these represent completely new compounds. The rare occurrence of these wax constituents makes them possible chemotaxonomic markers of this particular Dianthus sp.  相似文献   
12.
Conservation genetics is a well‐established scientific field. However, limited information transfer between science and practice continues to hamper successful implementation of scientific knowledge in conservation practice and management. To mitigate this challenge, we have established a conservation genetics community, which entails an international exchange‐and‐skills platform related to genetic methods and approaches in conservation management. First, it allows for scientific exchange between researchers during annual conferences. Second, personal contact between conservation professionals and scientists is fostered by organising workshops and by popularising knowledge on conservation genetics methods and approaches in professional journals in national languages. Third, basic information on conservation genetics has been made accessible by publishing an easy‐to‐read handbook on conservation genetics for practitioners. Fourth, joint projects enabled practitioners and scientists to work closely together from the start of a project in order to establish a tight link between applied questions and scientific background. Fifth, standardised workflows simplifying the implementation of genetic tools in conservation management have been developed. By establishing common language and trust between scientists and practitioners, all these measures help conservation genetics to play a more prominent role in future conservation planning and management.  相似文献   
13.
In recent literature, the concept of criticality aspires to provide a multifaceted risk assessment of resource supply shortage. However, most existing methodologies for the criticality assessment of raw materials are restricted to a fixed temporal and spatial reference system. They provide a snapshot in time of the equilibrium between supply and demand/economic importance and do not account for temporal changes of their indicators. The static character of criticality assessments limits the use of criticality methodologies to short‐term policy making of raw materials. In the current paper, we argue for an enhancement of the criticality framework to account for three key dynamic characteristics, namely changes of social, technical, and economic features; consideration of the spatial dimension in site‐specific assessments; and impact of changing governance frameworks. We illustrate how these issues were addressed in studies outside of the field of criticality and identify the dynamic parameters that influence resource supply and demand based on a review of studies that belong to the general field of resource supply and demand. The parameters are grouped in seven categories: extraction, social, economic, technical, policy, market dynamics, and environmental. We explore how these parameters were considered in the reviewed studies and propose ways and specific examples of addressing the dynamic effects in the criticality indicators. Furthermore, we discuss the current work on future scenarios to provide reference points for indicator benchmarks. The insights and guidelines derived from the review and our recommendations for future research set the foundations for an enhanced dynamic and site‐specific criticality assessment framework.  相似文献   
14.
15.
Non-coding variants have long been recognized as important contributors to common disease risks, but with the expansion of clinical whole genome sequencing, examples of rare, high-impact non-coding variants are also accumulating. Despite recent advances in the study of regulatory elements and the availability of specialized data collections, the systematic annotation of non-coding variants from genome sequencing remains challenging. Here, we propose a new framework for the prioritization of non-coding regulatory variants that integrates information about regulatory regions with prediction scores and HPO-based prioritization. Firstly, we created a comprehensive collection of annotations for regulatory regions including a database of 2.4 million regulatory elements (GREEN-DB) annotated with controlled gene(s), tissue(s) and associated phenotype(s) where available. Secondly, we calculated a variation constraint metric and showed that constrained regulatory regions associate with disease-associated genes and essential genes from mouse knock-outs. Thirdly, we compared 19 non-coding impact prediction scores providing suggestions for variant prioritization. Finally, we developed a VCF annotation tool (GREEN-VARAN) that can integrate all these elements to annotate variants for their potential regulatory impact. In our evaluation, we show that GREEN-DB can capture previously published disease-associated non-coding variants as well as identify additional candidate disease genes in trio analyses.  相似文献   
16.
A new separation-free method for detection of single nucleotide polymorphisms (SNPs) is described. The method is based on the single base extension principle, fluorescently labeled dideoxy nucleotides and two-photon fluorescence excitation technology, known as ArcDia™ TPX technology. In this assay technique, template-directed single base extension is carried out for primers which have been immobilized on polymer microparticles. Depending on the sequence of the template DNA, the primers are extended either with a labeled or with a non-labeled nucleotide. The genotype of the sample is determined on the basis of two-photon excited fluorescence of individual microparticles. The effect of various assay condition parameters on the performance of the assay method is studied. The performance of the new assay method is demonstrated by genotyping the SNPs of human individuals using double-stranded PCR amplicons as samples. The results show that the new SNP assay method provides sensitivity and reliability comparable to the state-of-the-art SNaPshot™ assay method. Applicability of the new method in routine laboratory use is discussed with respect to alternative assay techniques.  相似文献   
17.
Three groups of nine patients each were analyzed. The first two groups consisted of those that underwent tympanoplastic due to chronic inflammation of middle ear. Two different standard auditory canal skin incisions were applied, i.e. tympanomeatal flap (TMF) or vascular strip (VS). The third control group consisted of non-operated patients. All the operated patients were subjected to a quantitative analysis of the auditory canal revascularization by means of the Weibel stereological test method, i.e. the B 100 double network system. The density of capillaries, arterioles, venulolymphatic spaces and a total volume density of all vascular elements of the auditory canal skin were measured. The obtained results of vascularization were compared with those of the target control group. It was found out that there were no significant differences in vascularization of auditory canal skin between TMF and VS patients from one side and the control group on the other side.  相似文献   
18.
The ICF syndrome: new case and update   总被引:1,自引:0,他引:1  
The ICF syndrome: New case and update: We report the clinical progress in a 5-year-old boy with the (ICF) syndrome. Early diagnosis and intervention has led to a good outcome. DNMT3B mutation analysis was negative, supporting genetic heterogeneity in this condition.  相似文献   
19.
The present study was designed to evaluate the oxidative stress-related parameters in alloxan-induced diabetes in rabbits. After 3, 6, 12 and 24 weeks of hyperglycaemia the enzymatic and non-enzymatic factors were measured in heart tissue of diabetic and control groups. Superoxide dismutase and glutathione peroxidase activities and the contents of total sulfhydryl compounds significantly increased at all time intervals. Catalase activity increased initially (after 3 and 6 weeks), decreased after 12 weeks and increased again at the 24th week of the experiment. Glutathione reductase activity increased initially (at 3rd week), decreased below control level after 6 and 12 weeks, then increased again. Ascorbic acid concentration decreased after 3 and 6 weeks, and increased at the 12th and 24th weeks. The level of lipid peroxidation products was reduced after 3, 6 and 12 weeks of the experiment. After 24 weeks it was significantly elevated. These data suggest that hyperglycaemia induces oxidative stress in the heart but the defense mechanisms in the heart tissue are fairly efficacious against oxidative injury.  相似文献   
20.
The urokinase-type plasminogen activation system, including the serine protease uPA (urokinase-type plasminogen activator) and its cell surface receptor (uPAR, CD87), are important key molecules in tumor invasion and metastasis. Besides its proteolytic function, binding of uPA to uPAR on tumor cells exerts various cell responses such as migration, adhesion, proliferation, and differentiation. Hence, the uPA/uPAR system is a potential target for tumor therapy. We have designed a new generation of uPA-derived synthetic cyclic peptides suited to interfere with the binding of uPA to uPAR and present a new technology involving micro silica particles coated with uPA (SP-uPA) and reacting with recombinant soluble uPAR (suPAR), to rapidly assess the antagonistic potential of uPA-peptides by flow cytofluorometry (FACS). For this, we used silica particles of 10 microm in diameter to which HMW-uPA is coupled using the EDC/NHS method. Soluble, recombinant suPAR was added and the interaction of SP-uPA with suPAR verified by reaction with monoclonal antibody HD13.1 directed to uPAR, followed by a cyan dye (cy5)-labeled antibody directed against mouse IgG. Thereby it was possible to test naturally occurring ligands of uPAR (HMW-uPA, ATF) as well as highly effective, synthetic cyclic uPA-derived peptides (cyclo21,29[D-Cys21Cys29]-UPA21-30, cyclo21,29[D-Cys21Nle28Cys29]-uPA21-30, cyclo21,29[D-Cys(21)2-Nal24Cys29]-uPA21-30, and cyclo21,29[D-Cys21Orn23Thi24Thi25Cys29]-uPA21-30. The results obtained with the noncellular SP-uPA/uPAR system are highly comparable to those obtained with a cellular system involving FITC-uPA and the promyeloid cell line U937 as the source of uPAR.  相似文献   
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