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Three different types of fluorescence detection methods were employed to monitor amplification of a previously established isothermal cooperatively coupled amplification system as it can serve as a tool for the investigation of fundamental issues in evolutionary optimization. By using 5'IRD-41 fluorescent labeled primers, the intercalating dye TOPRO-1 and a 5'fluorescin/3'DABCYL 4-(4-dimethylamino-phenylazo)benzoic acid labeled ss 24 nt DNA, evolving molecular cooperation is accessible, sequence specifically as well as non-sequence-specifically without using radioactivity.  相似文献   
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Summary A simple technique of Giemsa staining is described giving characteristic banding patterns of human metaphase chromosomes; these patterns can be used to identify all 24 chromosome types.
Zusammenfassung Wir beschreiben eine einfache Methode, die mit geringem Zeitaufwand charakteristische Bandenmuster in menschlichen Metaphase-Chromosomen ergibt. Die Muster ermöglichen die Identifizierung aller 24 Chromosomentypen.


Director: Prof. Dr. W. Fuhrmann

Supported by the Deutsche Forschungsgemeinschaft and the Sonderforschungsbereich 35.  相似文献   
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This study aimed to investigate the association among genetic variants of the complement pathway CFB R32Q (rs641153), C3 R102G (rs2230199), and CFH (rs1410996) with age-related macular degeneration (AMD) in a sample of the Brazilian population. In a case-control study, 484 AMD patients were classified according to the clinical age-related maculopathy grading system (CARMS) and compared to 479 unrelated controls. The genetic variants rs1410996 of complement H (CFH), rs641153 of complement factor B (CFB), and rs2230199 of complement 3 (C3) were evaluated through polymerase chain reaction (PCR) and direct sequencing. The associations between single nucleotide polymorphisms (SNPs) and AMD, adjusted by age, were assessed by using logistic regression models. A statistically significant association was observed between AMD risk and rs2230199 variant with an OR of 2.01 (P  = 0.0002) for CG individuals compared to CC individuals. Regarding the comparison of advanced AMD versus the control group, the OR was 2.12 (P = 0.0036) for GG versus AA genotypes for rs1410996 variant. Similarly, the OR for rs2230199 polymorphism was 2.3034 (P  = 5.47e-05) when comparing CG individuals to CC carriers. In contrast, the rs641153 variant showed a significant protective effect against advanced AMD for GA versus GG genotype (OR = 0.4406; P  = 0.0019). When comparing wet AMD versus controls, a significant association was detected for rs1410996 variant (OR = 2.16; P  = 0.0039) comparing carriers of the homozygous GG versus AA genotype, as well as in the comparisons of GG (OR = 3.0713; P  = 0.0046) and CG genotypes (OR = 2.2249; P  = 0.0002) versus CC genotype for rs2230199 variant, respectively. The rs641153 variant granted a significant protective effect against wet AMD for GA versus GG genotypes (OR = 0.4601; P  = 0.0044). Our study confirmed the risk association between rs2230199 and rs1410996 variants and AMD, and the protective role against AMD for rs641153 variant.  相似文献   
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Magnesium (Mg) and calcium (Ca) are the principal essential elements involved in endothelial cell homeostasis. Extracellular changes in the levels of either alter endothelial contraction and dilatation. Consequently Mg and Ca imbalance is associated with a high risk of endothelial dysfunction, the main process observed during acute aortic dissection (AAD); in this clinical condition, which mainly affects elderly men, smooth muscle cell alterations lead to intimal tears, creating a false new lumen in the media of the aorta. AAD patients have a high risk of mortality as a result of late diagnosis because often it is not distinguished from other cardiovascular diseases. We investigated Mg and Ca total circulating levels and the associated pro-inflammatory mediators in elderly AAD patients, to gain further information on the pathophysiology of this disorder, with a view to suggesting newer and earlier potential biomarkers of AAD. Total circulating Mg and Ca levels were both lower in AAD patients than controls (p < 0.0001). Using Ca as cut-off, 90% of AAD patients with low Ca (<8.4 mg/dL) came into the type A classification of AAD. Stratifying AAD according to this cut-off, Mg was lower in patients with lower total Ca. Compared to controls, both type A and B AAD patients had higher levels of all the pro-coagulant and pro-inflammatory mediators analyzed, including sP-sel, D-dimer, TNF-α, IL-6, and CRP (p < 0.05). Dividing types A and B using the Stanford classification, no significant differences were found (p > 0.05) The levels of both ICAM-1 and EN-1 were lower in AAD than in a control group (p < 0.0001 and p < 0.05 respectively). These findings suggest that low Mg and Ca in AAD elderly patients may contribute to altering normal endothelial physiology and also concur in changing the normal concentrations of different mediators involved in vasodilatation and constriction, associated with AAD onset and severity.  相似文献   
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Sources of individual variation in plasma testosterone levels   总被引:2,自引:0,他引:2  
The steroid hormone testosterone (T) plays a central role in the regulation of breeding in males, because many physiological, morphological and behavioural traits related to reproduction are T dependent. Moreover, in many seasonally breeding vertebrates, male plasma T levels typically show a pronounced peak during the breeding season. While such population-level patterns are fairly well worked out, the sources and the implications of the large variability in individual T levels within the seasonal cycle remain surprisingly little understood. Understanding the potential sources of individual variation in T levels is important for behavioural and evolutionary ecologists, for at least two reasons. First, in 'honest signalling' theory, T is hypothesized to play a critical role as the assumed factor that enforces honesty of the expression of sexually selected quality indicators. Second, T is often considered a key mediator of central life-history trade-offs, such as investment in survival versus reproduction or in mating versus parental care. Here, we discuss the patterns of within- and between-individual variation in male plasma T levels in free-living populations of birds. We argue that it is unclear whether this variability mainly reflects differences in underlying individual quality (intrinsic factors such as genetic or maternal effects) or in the environment (extrinsic factors including time of day, individual territorial status and past experience). Research in avian behavioural endocrinology has mainly focused on the effects of extrinsic factors, while other sources of variance are often ignored. We suggest that studies that use an integrative approach and investigate the relative importance of all potential sources of variation are essential for the interpretation of data on individual plasma T levels.  相似文献   
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In many species, inbred individuals have reduced fitness. In plants with limited pollen and seed dispersal, post-pollination selection may reduce biparental inbreeding, but knowledge on the prevalence and importance of pollen competition or post-pollination selection after non-self pollination is scarce. We tested whether post-pollination selection favours less related pollen donors and reduces inbreeding in the dioecious plant Silene latifolia. We crossed 20 plants with pollen from a sibling and an unrelated male, and with a mix of both. We found significant inbreeding depression on vegetative growth, age at first flowering and total fitness (22% in males and 14% in females). In mixed pollinations, the unrelated male sired on average 57% of the offspring. The greater the paternity share of the unrelated sire, the larger the difference in relatedness of the two males to the female. The effect of genetic similarity on paternity is consistent with predictions for post-pollination selection, although paternity, at least in some crosses, may be affected by additional factors. Our data show that in plant systems with inbreeding depression, such as S. latifolia, pollen or embryo selection after multiple-donor pollination may indeed reduce inbreeding.  相似文献   
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Background

Wnt5a is a member of the wingless-type patterning regulators important in pre-natal development. The expression and distribution of Wnt5a and its receptors frizzled (fzd) 3 and fzd 5 in adult human skin have not been comprehensively studied to date.

Methodology/Principal Findings

We here show that Wnt5a, fzd3, fzd5, as well as fzd6 are restricted to specific layers in normal epidermis, analogous to their zonal distribution in hair follicles, suggesting a role in adult skin differentiation. In line, Wnt5a and fzd5 are both overexpressed and re-distributed in the epidermis of psoriasis which involves disturbed keratinocyte differentiation. Functionally, Wnt5a lowers the concentration of IFN required to induce target genes, and increases the magnitude of IFN target gene induction, suggesting a molecular mechanism underlying IFN hypersensitivity in psoriasis. Finally, we identify nedd8 and the amyloid precursor APP, previously shown to be upregulated in psoriasis, as targets of synergistic IFNα/Wnt5a induction.

Conclusions/Significance

The present data (i) suggest that Wnt5a regulates epidermal differentiation even in adult skin and (ii) identify synergistic induction of type 1 IFN target genes as a novel mode of Wnt5a action. Targeting Wnt5a in the skin may reduce IFN hypersensitivity and be of therapeutical value.  相似文献   
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