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Objective: The objective was to study the relationships between ultrasound estimated visceral fat and metabolic risk factors during early pregnancy. Research Methods and Procedures: Thirty consecutive healthy pregnant women at 11 to 14 weeks of gestation were studied. Maximum subcutaneous fat thickness (SFT) and visceral fat thickness (VFT) were successfully measured by ultrasound. Fasting plasma glucose, insulin, triglycerides, total cholesterol, high‐density lipoprotein cholesterol (HDL‐C), and blood pressure were measured. Insulin resistance was calculated by using the homeostasis model assessment (HOMA). Results: VFT significantly correlated with diastolic blood pressure (r = 0.37, p = 0.04), glycemia (r = 0.37, p = 0.04), insulinemia (r = 0.59, p = 0.001) insulin sensitivity (HOMA; r = 0.59, p = 0.001), triglycerides (r = 0.58, p = 0.03), HDL‐C (r = ?0.39, p = 0.03), and total cholesterol/HDL‐C ratio (p = 0.002), whereas SFT was significantly correlated with only diastolic blood pressure (p = 0.03). VFT better significantly correlated with the metabolic risk factors than pre‐gestational BMI [r = 0.39, p = 0.03 for insulinemia, r = 0.42, p = 0.02 for insulin sensitivity (HOMA), and r = 0.49, p = 0.01 for triglycerides and not significant for the rest]. Discussion: Visceral fat thickness can be easily measured by ultrasound at early pregnancy and correlates better than BMI with metabolic risk factors.  相似文献   
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The adoption of measures to protect the viability of threatened populations should be supported by empirical data identifying appropriate conservation units and management strategies. The global population of the majorera limpet, P. candei candei d’Orbigny, 1840, is restricted to the Macaronesian islands in the NE Atlantic, including near-to-extinct and healthy populations in Fuerteventura and Selvagens, respectively. The taxonomic position, genetic diversity and intra- and interspecific relationships of these populations are unclear, which is hindering the implementation of a recovery plan for the overexploited majorera limpet on Fuerteventura. In this study, ddRAD-based genome scanning was used to overcome the limitations of mitochondrial DNA-based analysis. As a result, P. candei candei was genetically differentiated from the closely related P. candei crenata for the first time. Moreover, genetic differentiation was detected between P. candei candei samples from Selvagens and Fuerteventura, indicating that translocations from the healthy Selvagens source population are inadvisable. In conclusion, the majorera limpet requires population-specific management focused on the preservation of exceptional genetic diversity with which to face future environmental challenges.

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Root cells take up K+ from the soil solution, and a fraction of the absorbed K+ is translocated to the shoot after being loaded into xylem vessels. K+ uptake and translocation are spatially separated processes. K+ uptake occurs in the cortex and epidermis whereas K+ translocation starts at the stele. Both uptake and translocation processes are expected to be linked, but the connection between them is not well characterized. Here, we studied K+ uptake and translocation using Rb+ as a tracer in wild‐type Arabidopsis thaliana and in T‐DNA insertion mutants in the K+ uptake or translocation systems. The relative amount of translocated Rb+ to the shoot was positively correlated with net Rb+ uptake rates, and the akt1 athak5 T‐DNA mutant plants were more efficient in their allocation of Rb+ to shoots. Moreover, a mutation of SKOR and a reduced plant transpiration prevented the full upregulation of AtHAK5 gene expression and Rb+ uptake in K+‐starved plants. Lastly, Rb+ was found to be retrieved from root xylem vessels, with AKT1 playing a significant role in K+‐sufficient plants. Overall, our results suggest that K+ uptake and translocation are tightly coordinated via signals that regulate the expression of K+ transport systems.  相似文献   
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Origins of Life and Evolution of Biospheres - In line with the postulated intermediacy of aminoxazoles derived from small sugars toward the direct assembly of nucleoside precursors, we show here a...  相似文献   
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Abstract Saccharomyces cerevisiae exponentially growing in basic or 0.7 M NaCl medium were isotopically labelled with 35S-methionine, followed by protein separation and quantification by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) combined with computerised image analysis. The electrophoretic separation resolved about 650 proteins of which 13 displayed significant and at least 2-fold changes in rate of synthesis during saline growth. By sequencing of 2D-PAGE resolved proteins, one of the 8 induced spot, p42.9/5.5, was shown to correspond to the full length (containing the N-terminal extension) product of the GPD 1 gene encoding the cytoplasmic glycerol 3-phosphate dehydrogenase. The expression of the TDH 3 gene, glyceraldehyde 3-phosphate dehydrogenase, and the ENO 2 gene, enolase, decreased during growth in NaCl medium, declines hypothesised to have an impact on the flux to glycerol.  相似文献   
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Animal toxins block voltage-dependent potassium channels (Kv) either by occluding the conduction pore (pore blockers) or by modifying the channel gating properties (gating modifiers). Gating modifiers of Kv channels bind to four equivalent extracellular sites near the S3 and S4 segments, close to the voltage sensor. Phrixotoxins are gating modifiers that bind preferentially to the closed state of the channel and fold into the Inhibitory Cystine Knot structural motif. We have solved the solution structure of Phrixotoxin 1, a gating modifier of Kv4 potassium channels. Analysis of the molecular surface and the electrostatic anisotropy of Phrixotoxin 1 and of other toxins acting on voltage-dependent potassium channels allowed us to propose a toxin interacting surface that encompasses both the surface from which the dipole moment emerges and a neighboring hydrophobic surface rich in aromatic residues.  相似文献   
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cDNA and genomic clones encoding a strawberry (Fragariaxananassa cv. Chandler) non-specific lipid transfer protein (Fxaltp gene) were isolated and characterized. The spatio-temporal expression pattern and structural features of this gene were studied for the first time in strawberry, a non-climacteric fruit of agricultural importance. The architecture and the encoded amino acid sequence of this non-climacteric fruit ltp gene were similar to those of other plant LTPs previously reported, and presents the eight cysteine residues and other features characteristic of plant LTPs. In addition, the deduced protein posseses an N-terminal signal peptide and lacks the K/HDEL retention signal, indicating that the strawberry LTP protein would enter the secretory pathway. In situ studies have shown that the Fxaltp gene is expressed in the epidermal cell layer of the strawberry fruit receptacle and achenes, flowers, and within the cell layer surrounding the endosperm. These results suggest that this Fxaltp gene promoter could be used as an endogenous promoter for biotechnological purposes in strawberry. Computer analysis using the PLACE database predicted the presence of several putative cis-regulatory sequences in response to abscisic acid and cold or wounding stresses within the Fxaltp 5'-flanking region. Accordingly, the strawberry gene responds to ABA and SA, but not to salt and heat stresses. It is also reported that ltp gene expression in strawberry is stimulated by wounding and repressed by cold stresses.  相似文献   
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