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101.
102.
Doreen Zegers Sigri Beckers Fenna de Freitas Armand V. Peeters Ilse L. Mertens Stijn L. Verhulst Raoul P. Rooman Jean‐Pierre Timmermans Kristine N. Desager Guy Massa Luc F. van Gaal Wim van Hul 《Obesity (Silver Spring, Md.)》2011,19(1):152-159
The melanocortin‐3 receptor (MC3R), a G‐protein‐coupled receptor expressed in the hypothalamus, is a key component of the leptin‐melanocortin pathway that regulates energy homeostasis. It is suggested that an MC3R defect leads to an increased feed efficiency, by which nutrients are partitioned preferentially into fat. In this study, we hypothesized that early‐onset obesity could be induced by mutations in MC3R. To investigate this hypothesis, we screened the entire coding region of the MC3R gene for mutations in obese subjects. A total of 404 overweight and obese children and adolescents, 86 severely obese adults (BMI ≥40 kg/m2), and 150 normal‐weight control adults were included. Besides three synonymous coding variations in the MC3R gene (S69S, L95L, I226I), we were able to identify three novel heterozygous, nonsynonymous, coding mutations (N128S, V211I, L299V) in three unrelated obese children. None of these mutations were found in any of the control subjects. Functional studies assessing localization and signaling properties of the mutant receptors provided proof for impaired function of the L299V mutated receptor, whereas no conclusive evidence for functional impairment of the N128S and V211I mutated receptors could be established. First, these results provide supporting evidence for a role of the MC3R gene in the pathogenesis of obesity in a small subset of patients. Second, they show that caution is called for the interpretation of newly discovered mutations in MC3R. 相似文献
103.
Influence of certain soil factors on chocolate spot of beans 总被引:1,自引:0,他引:1
In the summer of 1941 chocolate spot of beans was widespread in the South-Eastern Agricultural Province and caused much damage to the crop. Soil samples were collected from forty-nine affected fields on a variety of soil types, and the relation between the severity of attack by chocolate spot and the texture, pH, available potassium and available phosphorus determined. Severity of attack was classified into three grades: 'slight', in which only spotting of the foliage occurred; 'moderate', in which death of leaves and blossoms on the three or four lowest nodes occurred; and 'severe', in which there was generally a total loss of crop. No significant relation between severity of attack and soil texture, pH or available potassium was found. A highly significant relation was found to exist between the severity of attack and the amount of available phosphorus in the soil as determined by the method of soil analysis used in this Province. Damage by chocolate spot was generally slight on soils containing 'medium to medium high' or higher amounts of available phosphorus, and generally severe on soils containing low amounts of available phosphorus. 相似文献
104.
Tabitha R. Siegfried Mariana M. P. B. Fuentes Matthew Ware Nathan J. Robinson Emma Roberto Joseph R. Piacenza Susan E. Piacenza 《Ecology and evolution》2021,11(12):8226
Point 1: Stereo‐video camera systems (SVCSs) are a promising tool to remotely measure body size of wild animals without the need for animal handling. Here, we assessed the accuracy of SVCSs for measuring straight carapace length (SCL) of sea turtles.Point 2: To achieve this, we hand captured and measured 63 juvenile, subadult, and adult sea turtles across three species: greens, Chelonia mydas (n = 52); loggerheads, Caretta caretta (n = 8); and Kemp''s ridley, Lepidochelys kempii (n = 3) in the waters off Eleuthera, The Bahamas and Crystal River, Florida, USA, between May and November 2019. Upon release, we filmed these individuals with the SVCS. We performed photogrammetric analysis to extract stereo SCL measurements (eSCL), which were then compared to the (manual) capture measurements (mSCL).Point 3: mSCL ranged from 25.9 to 89.2 cm, while eSCL ranged from 24.7 to 91.4 cm. Mean percent bias of eSCL ranged from −0.61% (±0.11 SE) to −4.46% (±0.31 SE) across all species and locations. We statistically analyzed potential drivers of measurement error, including distance of the turtle to the SVCS, turtle angle, image quality, turtle size, capture location, and species.Point 4: Using a linear mixed effects model, we found that the distance between the turtle and the SVCS was the primary factor influencing measurement error. Our research suggests that stereo‐video technology enables high‐quality measurements of sea turtle body size collected in situ without the need for hand‐capturing individuals. This study contributes to the growing knowledge base that SVCS are accurate for body size measurements independent of taxonomic clade. 相似文献
105.
The effects of time and temperature on flow cytometry enumerated live Cryptosporidium parvum oocysts
AIMS: Recoveries of spiked standard suspensions are used to evaluate method performance. For many applications, gamma-irradiated Cryptosporidium oocysts are appropriate. In contrast, methods that determine viability, such as Cryptosporidium cell culture, require the use of live oocysts. Oocyst standards are usually prepared at a flow cytometry laboratory for use at another laboratory, and thus the samples are shipped. The goal of this study was to evaluate the shipping and storage stability of flow cytometry enumerated live oocysts over time at three temperatures: 4 degrees C, room temperature and 37 degrees C. METHODS AND RESULTS: Replicate samples containing 100 live C. parvum oocysts were prepared by flow cytometry and stored at 4 degrees C, room temperature and 37 degrees C. These samples were counted at various time points. Significant oocyst losses were observed after storage for 1 day at 37 degrees C, 7 days at room temperature and 21 days at 4 degrees C. CONCLUSIONS: Live C. parvum oocysts internal standards should be used within 10 days of preparation, and stored and shipped at 4 degrees C. SIGNIFICANCE AND IMPACT OF THE STUDY: When evaluating method performance with live oocysts, both the storage temperature and time are critical factors for obtaining reliable and accurate results. 相似文献
106.
Mayhew JL Bird M Cole ML Koch AJ Jacques JA Ware JS Buford BN Fletcher KM 《Journal of strength and conditioning research / National Strength & Conditioning Association》2005,19(3):514-518
The purpose of this study was to determine the relationship of the backward overhead medicine ball (BOMB) throw to power production in college football players. Forty National Collegiate Athletic Association Division II college football players were studied at the end of an 8-week off-season conditioning program for power output determined from a countermovement vertical jump on a force plate and for maximal distance in the standing BOMB throw. Although the reliability of the BOMB test was high (interclass correlation coefficient = 0.86), there was a significant learning effect across 3 trials (p < 0.01). Peak and average powers generated during the vertical jump correlated moderately but significantly with the best BOMB throw distance (r = 0.59 and 0.63, respectively). Considering power relative to body mass or lean body mass failed to produce significant correlations with BOMB throw distance (r = 0.27 and 0.28, respectively). Therefore, the BOMB throw may have limited potential as a predictor of total body explosive power in college football players. 相似文献
107.
Tian X Field T Mazur AW Ebetino FH Wos JA Crossdoersen D Pinney BB Sheldon RJ 《Bioorganic & medicinal chemistry letters》2005,15(11):2819-2823
A series of proline based melanocortin ligands has been developed on the basis of initial piperazine leads by using a more conformationally rigid scaffold. A number of these novel ligands showed significant binding affinity for MC3 and MC4 receptors. 相似文献
108.
Dual phospholipase C/diacylglycerol requirement for protein kinase D1 activation in lymphocytes 总被引:2,自引:0,他引:2
The serine/threonine kinase protein kinase D1 (PKD1) is a protein kinase C (PKC) substrate that mediates antigen receptor signal transduction in lymphocytes. PKC phosphorylates serines 744/748 within the PKD1 catalytic domain, and this is proposed to be necessary and sufficient for enzyme activation. Hence, a PKD1 mutant with alanine substituted at positions 744 and 748 (PKD-S744A/S748A) is catalytically inactive. Conversely, a PKD1 mutant with glutamic residues substituted at positions 744 and 748 as phospho-mimics (PKD-S744E/S748E) is constitutively active when expressed in Cos7 or HeLa cells. The present study reveals that Ser-744/Ser-748 phosphorylation is required for PKD1 activation in lymphocytes. However, PKD-S744E/S748E is not constitutively active but, like the wild type enzyme, requires antigen receptor triggering or phorbol ester stimulation. Antigen receptor activation of wild type PKD is dependent on phospholipase C (PLC)/diacylglycerol (DAG) and PKC, whereas PKD-S744E/S748E is only dependent on PLC/DAG but no longer requires PKC. Hence, substitution of serines 744 and 748 with glutamic residues as phospho-mimics bypasses the PKC requirement for PKD1 activation but does not bypass the need for antigen receptors, PLC, or DAG. In lymphocytes, PKD1 is, thus, not regulated by PLC and PKC in a linear pathway; rather, PKD1 activation has more stringent requirements for integration of dual PLC signals, one mediated by PKCs and one that is PKC-independent. 相似文献
109.
Mure M Kurtis CR Brown DE Rogers MS Tambyrajah WS Saysell C Wilmot CM Phillips SE Knowles PF Dooley DM McPherson MJ 《Biochemistry》2005,44(5):1583-1594
Adduct I (lambda(max) at approximately 430 nm) formed in the reaction of 2-hydrazinopyridine (2HP) and the TPQ cofactor of wild-type Escherichia coli copper amine oxidase (WT-ECAO) is stable at neutral pH, 25 degrees C, but slowly converts to another spectroscopically distinct species with a lambda(max) at approximately 530 nm (adduct II) at pH 9.1. The conversion was accelerated either by incubation of the reaction mixture at 60 degrees C or by increasing the pH (>13). The active site base mutant forms of ECAO (D383N and D383E) showed spectral changes similar to WT when incubated at 60 degrees C. By contrast, in the Y369F mutant adduct I was not stable at pH 7, 25 degrees C, and gradually converted to adduct II, and this rate of conversion was faster at pH 9. To identify the nature of adduct II, we have studied the effects of pH and divalent cations on the UV-vis and resonance Raman spectroscopic properties of the model compound of adduct I (2). Strikingly, it was found that addition of Cu2+ to 2 at pH 7 gave a product (3) that exhibited almost identical spectroscopic signatures to adduct II. The X-ray crystal structure of 3 shows that it is the copper-coordinated form of 2, where the +2 charge of copper is neutralized by a double deprotonation of 2. These results led to the proposal that adduct II in the enzyme is TPQ-2HP that has migrated onto the active site Cu2+. The X-ray crystal structure of Y369F adduct II confirmed this assignment. Resonance Raman and EPR spectroscopy showed that adduct II in WT-ECAO is identical to that seen in Y369F. This study clearly demonstrates that the hydrogen-bonding interaction between O4 of TPQ and the conserved Tyr (Y369) is important in controlling the position and orientation of TPQ in the catalytic cycle, including optimal orientation for reactivity with substrate amines. 相似文献
110.
Look-Align: an interactive web-based multiple sequence alignment viewer with polymorphism analysis support 总被引:2,自引:0,他引:2
SUMMARY: We have developed Look-Align, an interactive web-based viewer to display pre-computed multiple sequence alignments. Although initially developed to support the visualization needs of the maize diversity website Panzea (http://www.panzea.org), the viewer is a generic stand-alone tool that can be easily integrated into other websites. AVAILABILITY: Look-Align is written in Perl using open-source components and is available under an open-source license. Live installation and download information can be found at the Panzea website (http://www.panzea.org/software/alignment_viewer.html). CONTACT: ware@cshl.edu SUPPLEMENTARY INFORMATION: The Supplementary information includes sample lists of multiple sequence alignment software and sample screenshots of the viewer. 相似文献