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81.
Kohta Suzuki Miri Sato Wei Zheng Ryoji Shinohara Hiroshi Yokomichi Zentaro Yamagata 《PloS one》2015,10(2)
Pregestational weight status and maternal smoking during pregnancy are significantly associated with fetal and childhood growth. However, few studies have examined associations between childhood growth and combinations of these factors using multilevel analysis. This study aimed to describe differences in childhood growth trajectories according to these combinations, using data from a prospective cohort study in Japan. The study participants were 1,973 women and their singletons, who were born between April 1, 1991 and March 31, 2003. Children were categorized according to whether they were born to normal-weight, nonsmoking mothers (NN); normal-weight, smoking mothers (NS); underweight, nonsmoking mothers (UN); underweight, smoking mothers (US); overweight, nonsmoking mothers (ON); or overweight, smoking mothers (OS). Birth weight and anthropometric data were collected from 1,965 children at birth (99.6%), 1,655 aged 3 (83.9%), 1,527 aged 5 (77.4%), 1,497 aged 7–8 (75.9%), and 1,501 aged 9–10 (76.1%). Multilevel analysis examining both individual and age as different level variables according to sex was used to describe the trajectories of body mass index z scores for statistical analyses. Although children of the OS group were the leanest at birth, their body mass indices had increased rapidly by 3 years of age. Moreover, body mass index was also likely to increase in boys in the NS and ON groups. A different trend was observed in girls. Body mass index decreased from 5 years of age in girls in the US group. There were no remarkable differences in body mass index trajectories between children in the other groups. In conclusion, childhood growth trajectories differed according to combinations of pregestational weight status and maternal smoking during pregnancy. Further, there were sex-related differences in the associations between childhood growth and factor combinations. 相似文献
82.
David W. Killilea Jodi L. Westropp Ryoji Shiraki Matthew Mellema Jennifer Larsen Arnold J. Kahn Pankaj Kapahi Thomas Chi Marshall L. Stoller 《PloS one》2015,10(6)
One of the most common types of urinary stones formed in humans and some other mammals is composed of calcium oxalate in ordered hydrated crystals. Many studies have reported a range of metals other than calcium in human stones, but few have looked at stones from animal models such as the dog. Therefore, we determined the elemental profile of canine calcium oxalate urinary stones and compared it to reported values from human stones. The content of 19 elements spanning 7-orders of magnitude was quantified in calcium oxalate stones from 53 dogs. The elemental profile of the canine stones was highly overlapping with human stones, indicating similar inorganic composition. Correlation and cluster analysis was then performed on the elemental profile from canine stones to evaluate associations between the elements and test for potential subgrouping based on elemental content. No correlations were observed with the most abundant metal calcium. However, magnesium and sulfur content correlated with the mineral hydration form, while phosphorous and zinc content correlated with the neuter status of the dog. Inter-elemental correlation analysis indicated strong associations between barium, phosphorous, and zinc content. Additionally, cluster analysis revealed subgroups within the stones that were also based primarily on barium, phosphorous, and zinc. These data support the use of the dog as a model to study the effects of trace metal homeostasis in urinary stone disease. 相似文献
83.
The photoreceptors for chloroplast photorelocation movement have been known, but the signal(s) raised by photoreceptors remains unknown. To know the properties of the signal(s) for chloroplast accumulation movement, we examined the speed of signal transferred from light-irradiated area to chloroplasts in gametophytes of Adiantum capillus-veneris. When dark-adapted gametophyte cells were irradiated with a microbeam of various light intensities of red or blue light for 1 min or continuously, the chloroplasts started to move towards the irradiated area. The speed of signal transfer was calculated from the relationship between the timing of start moving and the distance of chloroplasts from the microbeam and was found to be constant at any light conditions. In prothallial cells, the speed was about 1.0 µm min−1 and in protonemal cells about 0.7 µm min−1 towards base and about 2.3 µm min−1 towards the apex. We confirmed the speed of signal transfer in Arabidopsis thaliana mesophyll cells under continuous irradiation of blue light, as was about 0.8 µm min−1. Possible candidates of the signal are discussed depending on the speed of signal transfer.Key words: Adiantum capillus-veneris, Arabidopsis thaliana, blue light, chloroplast movement, microbeam, red light, signalOrganelle movement is essential for plant growth and development and tightly regulated by environmental conditions.1 It is well known that light regulates chloroplast movement in various plant species. Chloroplast movement can be separated into three categories, (1) photoperception by photoreceptors, (2) signal transduction from photoreceptor to chloroplasts and (3) movement of chloroplasts and has been analyzed from a physiological point of view.2 We recently identified the photoreceptors in Arabidopsis thaliana, fern Adiantum capillus-veneris, and moss Physcomitrella patens. In A. thaliana, phototropin 2 (phot2) mediates the avoidance movement,3,4 whereas both phototropin 1 (phot1) and phot2 mediate the accumulation response.5 A chimeric photoreceptor neochrome 1 (neo1)6 was identified as a red/far-red and blue light receptor that mediates red as well as blue light-induced chloroplast movement in A. capillusveneris.7 Interestingly, neo1 mediated red and blue light-induced nuclear movement and negative phototropic response of A. capillus-veneris rhizoid cells.8,9 On the mechanism of chloroplast movement, we also found a novel structure of actin filaments that appeared between chloroplast and the plasma membrane at the front side of moving chloroplast.10 Recent studies using the technique of microbeam irradiation have revealed that chloroplasts do not have a polarity for light-induced accumulation movement and can move freely in any direction both in A. capillus-veneris prothallial cells and in A. thaliana mesophyll cells.11 However, the signal that may be released from photoreceptors and transferred to chloroplasts remains unknown.To understand the properties of the signal for the chloroplast accumulation response, we examined the speed of signal transfer in dark-adapted A. capillus-veneris gametophyte cells and A. thaliana mesophyll cells by partial cell irradiation with a red and/or blue microbeam of various light intensities for 1 min and the following continuous irradiation, respectively.12As shown in Figure 1, the relation between the distance of chloroplasts from the microbeam and the timing when each chloroplast started moving toward the microbeam irradiated area (shown as black dots in Fig. 1) was obtained and plotted. The lag time between the onset of microbeam irradiation and the timing of start moving of chloroplasts is the time period needed for a signal to reach each chloroplast. To obtain more accurate data many chloroplasts at various positions were used. The slope of the approximate line indicates the average speed of the signal transfer. Shown with a protonemal cell at the left side of this figure is an instance where the speed of signal transfer from basal-to-apical (acropetal) direction is obtained.Open in a separate windowFigure 1How to calculate the speed of signal transfer in the basal cell of two-celled protonema of Adiantum capillus-veneris. The relationship between the distance of chloroplast position from the edge of the microbeam to the center of each chloroplast as shown in left side of figure and the timing of chloroplast movement initiated shown as the black dots was obtained. Inclination of the approximate lines connecting dots indicates the speeds of the signal transfer.In protonemal cells, which are tip-growing linear cells, the average speed of signal transfer was about 2.3 µm min−1 from basal-to-apical (acropetal) and about 0.7 µm min−1 from apical-to-basal (basipetal) directions. These values were almost constant irrespective of light intensity, wavelength, irradiation period, and the region of the cell irradiated.12 The difference of speed between basipetal and acropetal directions may be depending on cell polarity. The signal transfer in prothallial cells of A. capillus-veneris and mesophyll cells of A. thaliana was about 1.0 µm min−1 to any direction, probably because they may not have a polarity comparing to protonemal cells or have a weak polarity if any. Thus, the speed of signal transfer must be conserved in most land plants,12 if not influenced by strong polarity. R1W m−2 R1W m−2 B1W m−2 R0.1W m−2 R10W m−2 B10W m−2 1 min countinuous countinuous countinuous countinuous countinuous Protonemal cell (towards apical region) 2.32 2.37 2.28 2.41 2.39 Protonemal cell (towards basal region) 0.58 0.73 0.80 0.74 0.86 Prothallial cell 1.13 0.92 1.10 1.08 0.95 Arabidopsis thaliana 0.70