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51.
The hypothalamo-neurohypophyseal system (HNS) is?the neurovascular structure through which the hypothalamic neuropeptides oxytocin and arginine-vasopressin exit the brain into the bloodstream, where they go on to affect peripheral physiology. Here, we investigate the molecular cues that regulate the neurovascular contact between hypothalamic axons and neurohypophyseal capillaries of the zebrafish. We developed a transgenic system in which both hypothalamic axons and neurohypophyseal vasculature can be analyzed in?vivo. We identified the cellular organization of the zebrafish HNS as well as the dynamic processes that contribute to formation of the HNS neurovascular interface. We show that formation of this interface is regulated during development by local release of oxytocin, which affects endothelial morphogenesis. This cell communication process is essential for the establishment of a tight axovasal interface between the neurons and blood vessels of the HNS. We present a unique example of axons affecting endothelial morphogenesis through secretion of a neuropeptide.  相似文献   
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The fatty acid and alcohol composition of the mesozooplanktonspecies analysed indicated a diatom-based diet in late summer.For the majority of organisms investigated, an opportunisticfeeding behaviour is assumed.  相似文献   
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Using historical data from the Utah Population Database, this analysis finds significant, consistent, but small adverse mortality effects for mothers after age 50 who had mostly sons. Examination of age-dependent effects indicates that this association increases with mother’s age. Additionally, mothers who had mostly daughters faced mortality risks that increased with age. Offspring sex composition did not have a significant effect on paternal mortality. Interaction analyses were conducted to examine the effect of offspring sex composition with regard to historical period, residential location, socioeconomic status, and childhood survival. No other interactions were found to be statistically significant. Having mostly boys remained detrimental to maternal mortality regardless of childhood survival.
Ken R. SmithEmail:
  相似文献   
55.
A series of N-heterocyclic dipeptide aldehydes 4-13 have been synthesised and evaluated as inhibitors of ovine calpain 1 (o-CAPN1) and ovine calpain 2 (o-CAPN2). 5-Formyl-pyrrole 9 (IC(50) values of 290 and 25nM against o-CAPN1 and o-CAPN2, respectively) was the most potent and selective o-CAPN2 inhibitor, displaying >11-fold selectivity. The amino acid sequences of o-CAPN1 and o-CAPN2 have been determined. Because of the lack of available structural information on the ovine calpains, in silico homology models of the active site cleft of o-CAPN1 and o-CAPN2 were developed based on human calpain 1 (h-CAPN1) X-ray crystal structure (PDB code 1ZCM). These models were used to rationalise the observed SAR for compounds 4-13 and the selectivity observed for 9. The o-CAPN2 selective inhibitor 9 (CAT0059) was assayed in an in vitro ovine lens culture system and shown to successfully protect the lens from calcium-induced opacification.  相似文献   
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Ecosystems - Decomposition of dead fine roots contributes significantly to nutrient cycling and soil organic matter stabilization. Most knowledge of tree fine-root decomposition stems from studies...  相似文献   
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The circulatory system is the first organ system that develops during embryogenesis, and is essential for embryo viability and survival. Crucial for developing a functional vasculature are the specification of arterial-venous identity in vessels and the formation of a hierarchical branched vascular network. Sprouting angiogenesis, intussusception, and flow driven remodeling events collectively contribute to establishing the vascular architecture. At the molecular level, arterial-venous identity and branching are regulated by genetically hardwired mechanisms involving Notch, vascular endothelial growth factor and neural guidance molecule signaling pathways, modulated by hemodynamic factors. MicroRNAs are small, non-coding RNAs that act as silencers to fine-tune the gene expression profile. MicroRNAs are known to influence cell fate decisions, and microRNA expression can be controlled by blood flow, thus placing microRNAs potentially at the center of the genetic cascades regulating vascular differentiation. In the present review, we summarize current progress regarding microRNA functions in blood vessel development with an emphasis on studies performed in zebrafish and mouse models.  相似文献   
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Stressful life events, especially Childhood Trauma, predict ADHD symptoms. Childhood Trauma and negatively biased memory are risk factors for affective disorders. The association of life events and bias with ADHD symptoms may inform about the etiology of ADHD. Memory bias was tested using a computer task in N = 675 healthy adults. Life events and ADHD symptoms were assessed using questionnaires. The mediation of the association between life events and ADHD symptoms by memory bias was examined. We explored the roles of different types of life events and of ADHD symptom clusters. Life events and memory bias were associated with overall ADHD symptoms as well as inattention and hyperactivity/impulsivity symptom clusters. Memory bias mediated the association of Lifetime Life Events, specifically Childhood Trauma, with ADHD symptoms. Negatively biased memory may be a cognitive marker of the effects of Childhood Trauma on the development and/or persistence of ADHD symptoms.  相似文献   
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