bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transformation of isolated barley (Hordeum vulgareL.) microspores: II. Timing of pretreatment and temperatures relative to results of bombardment
Authors: Shim Youn-Seb , Pauls K. Peter , Kasha Ken J. 
Published: February 2009

Based on paper I in this series, our goals in this paper were to determine the relationship between prebombardment pretreatments and temperatures, microspore cell cycle when bombarded, and the frequencies of homozygous and hemizygous transgenic progeny in barley ( Hordeum vulgare L.). Of the 104 fluorescent plants selected when using the GFP fluorescence transgene, 28 were albino and 76 plants were green. Thirty-one green plants were confirmed to be transgenic; the others were either transient green fluorescent protein expression or selected due to autofluorescence. Of the 31 plants, 23 came from embryos expressing a high level of fluorescence during selection and eight from 51 plants exhibiting a low level of fluorescence. Of the two pretreatments used to induce embryogenesis, 24 of 31 plants were from the cold pretreatment for 21 days (C) versus seven from the 4 day cold plus mannitol pretreatment. Following pretreatment, the microspores were subjected to a high-osmotic period (0.5 mol/L mannitol plus sorbitol) of 4 h prebombardment and 18 h postbombardment at either 25 or 4 °C. Of the 31 transgenic plants, 19 were produced following the 25 °C 4 h prebombardment. Sixteen of the 19 were doubled haploid plants (seven being homozygous for the transgene) and the other three plants were haploid. Of the remaining 12 plants recovered following the 4 h 4 °C prebombardment treatment, nine were haploid and three were doubled haploid plants, two of the latter being homozygous for the transgene. All 12 haploid plants obtained were treated with colchicine and produced homozygous transgenic doubled haploids. Of the two promoters compared, 30 plants had the actin promoter and only one had the 35S promoter. The use of arabinogalactan protein in the culture medium was very beneficial, giving rise to 29 of the 31 plants. The best procedure for obtaining transgenic barley plants from this study was pretreatment C, leaving the cultures at either 4 or 25 °C during the 4 h prebombardment high-osmotic period, using the actin promoter and having arabinogalactan protein in the microspore culture medium. With this procedure, the transgenic frequency was improved 8- to10-fold over previous reports on bombardment of microspores. It yielded about one transgenic plant per Petri dish and is comparable with Agrobacterium frequencies on structures derived from microspores.
Development of SCAR markers for sex determination in the dioecious shrub Aucuba japonica (Cornaceae)
Authors: Maki Masayuki 
Published: February 2009

Two sex-linked fragments were identified by RAPD analyses in the dioecious diploid shrub Aucuba japonica var. ovoidea and were converted into markers of male-specific sequence characterized amplified region (SCAR) markers. PCRs using the primers designed in this study correctly discriminated 24 flowering males and 24 flowering females at higher annealing temperatures (SCAR markers OPA10-424 at 55 °C and OPN11-1095 at 65 °C), although at relatively low annealing temperatures, the fragments were amplified in both males and females. These SCAR primers were also tested to see whether they were applicable to sex identification in the conspecific tetraploid Aucuba japonica var. japonica. One set pf SCAR primers could be used for sex identification even in this tetraploid variety, although the other failed. The SCAR markers developed in this study will provide a powerful tool in identifying the sex of immature plants of dioecious A. japonica, which is a commercially valuable shrub due to its conspicuous fruits.
Delimitation of thePSH1(t) gene for rice purple leaf sheath to a 23.5 kb DNA fragment
Authors: Wang Wen-Ying , Ding Han-Feng , Li Guang-Xian , Jiang Ming-Song , Li Run-Fang , Liu Xu , Zhang Yu , Yao Fang-Yin 
Published: February 2009

Leaf sheath color plays an important role as a marker for rice genetic improvement. A recombinant inbred line (RIL) population consisting of 220 individuals was developed from a cross between an Oryza sativa subsp. indica variety, IRBB60, and an Oryza sativa subsp. japonica variery, 9407. Within the RIL population, a line, RI51, was found to have purple leaf sheath (PSH). To map the gene governing PSH, RI51 was crossed with 9407 green leaf sheath (GSH) to develop an F2segregating population. The distribution of F2plants with PSH and GSH fitted a segregation ratio of 3:1, indicating that the PSH was controlled by a major dominant gene. The gene locus for PSH, tentatively designated as PSH1(t), was identified by surveying two bulks made of the respective 40 individuals with PSH and GSH with SSR markers covering the entire rice genome. The survey indicated that the PSH1(t) region was located on chromosome 1. Further confirmation was made using a large random sample of 360 individuals from the same F2population and the PSH1(t) locus was then mapped on chromosome 1 between SSR markers RM3475 and RM7202 with genetic distances of 2.0 and 1.1 cM, respectively. For fine mapping of PSH1(t), a large F2:3segregating population with 3300 individuals from the seven heterozygous F2plants in the RM3475–RM7202 region was constructed. Analysis of recombinants in the PSH1(t) region anchored the gene locus to an interval of 23.5 kb flanked by the left marker L03 and the right marker L05. Sequence analysis of this fragment predicted six open reading frames encoding a putative trans-sialidase, a putative Plastidic ATP/ADP-transporter, and four unknown proteins. The detailed genetic and physical maps of the PSH1(t) locus will be very useful in molecular cloning of the PSH1(t) gene.
Construction of chromosomal recombination maps of three genomes of lilies (Lilium) based on GISH analysis
Authors: Khan Nadeem , Barba-Gonzalez Rodrigo , Ramanna M. S. , Visser Richard G.F. , Van Tuyl Jaap M. 
Published: February 2009

Chromosomal recombination maps were constructed for three genomes of lily ( Lilium ) using GISH analyses. For this purpose, the backcross (BC) progenies of two diploid (2n = 2x = 24) interspecific hybrids of lily, viz. Longiflorum × Asiatic (LA) and Oriental × Asiatic (OA), were used. Mostly the BC progenies of LA hybrids consisted of both triploid (2n = 3x = 36) and diploid (2n = 2x = 24) with some aneuploid genotypes and those of OA hybrids consisted of triploid (2n = 3x = 36) and some aneuploid genotypes. In all cases, it was possible to identify the homoeologous recombinant chromosomes as well as accurately count the number of crossover points, which are called “recombination sites”. Recombination sites were estimated in the BC progeny of 71 LA and 41 OA genotypes. In the case of BC progenies of LA hybrids, 248 recombination sites were cytologically localized on 12 different chromosomes of each genome (i.e., L and A). Similarly, 116 recombinant sites were localized on the 12 chromosomes each from the BC progenies of OA hybrids (O and A genomes). Cytological maps were constructed on the basis of the percentages of distances (micrometres) of the recombination sites from the centromeres. Since an Asiatic parent was involved in both hybrids, viz. LA and OA, two maps were constructed for the A genome that were indicated as Asiatic (L) and Asiatic (O). The other two maps were Longiflorum (A) and Oriental (A). Remarkably, the recombination sites were highly unevenly distributed among the different chromosomes of all four maps. Because the recombination sites can be unequivocally identified through GISH, they serve as reliable landmarks and pave the way for assigning molecular markers or desirable genes to chromosomes of Lilium and also monitor introgression of alien segments.
Characterization of a tandemly repeated subtelomeric sequence with inverted telomere repeats in maize
Authors: Li Jun , Yang Fei , Zhu Jia , He Shibin , Li Lijia 
Published: February 2009

In this study, two complementary telomere primers were applied to a single-primer PCR. A clear amplification band was obtained with one primer, while a smear pattern was seen with the other primer. Sequence analysis of the isolated clones from this specific amplification band revealed that a 412 bp clone designated as MTAS1 shared high homology with a reported subtelomeric sequence (382 bp) from maize ( Zea mays L.), which indicated that this clone was possibly present at subtelomeric regions. The clone MTAS1 displayed a novel structural feature flanked by the forward and inverted telomere repeats. Southern hybridization revealed a ladder of hybridization bands, suggesting that MTAS1 was a tandemly repeated sequence. Fluorescence in situ hybridization results showed that the strong MTAS1 signals were present at the ends of short arms of several long chromosomes, confirming that MTAS1 was a subtelomeric sequence and the high brightness of signals further indicated this cloned sequence was a highly and tandemly repetitive sequence in maize. Fluorescence in situ hybridization with telomeric DNA and MTAS1 as probes on metaphase chromosomes and extended genomic DNA fibers showed that hybridization signals of this clone located adjacent to or overlapped with signals of telomere tandem repeats distributed heterogeneously in subtelomeric regions of several chromosomes and even exhibited differences in two subtelomeres of a single chromosome.
An acute bout of endurance exercise but not sprint interval exercise enhances insulin sensitivity
Authors: Brestoff Jonathan R. , Clippinger Benjamin , Spinella Thomas , von Duvillard Serge P. , Nindl Bradley , Arciero Paul J. 
Published: February 2009

An acute bout of endurance exercise (EE) enhances insulin sensitivity, but the effects of sprint interval exercise (SIE) have not yet been described. We sought to compare insulin sensitivity at baseline and after an acute bout of EE and SIE in healthy men (n = 8) and women (n = 5) (age, 20.7 ± 0.3 years; peak oxygen consumption (VO2 peak), 42.6 ± 1.7 mL·kg–1·min–1; <1.5 days·week–1 structured exercise; body fat, 21.1 ± 1.9%). Subjects underwent 3 oral glucose tolerance tests (OGTTs) the day after each of the following 3 conditions: no exercise, baseline (OGTTB); SIE at ~125% VO2 peak (OGTTSIE); and EE at ~75% VO2 peak (OGTTEE). SIE and EE sessions were randomized for each subject. Subjects consumed identical meals the day preceding each OGTT. Two insulin sensitivity indices — composite whole-body insulin sensitivity index (ISI-COMP) and ISI-hepatic insulin sensitivity (HOMA) — were calculated, using previously validated formulas (ISI-COMP = 10 000/√(glucosefasting × insulinfasting × glucosemean OGTT × insulinmean OGTT); ISI-HOMA = 22.5/(insulinfasting × glucosefasting)), and the plasma concentrations of cytokines interleukin-6 and tumor necrosis factor-α were measured. There were no differences by sex for any condition (men vs. women, p > 0.05). Pearson’s correlation coefficients between ISI-COMP and ISI-HOMA for each condition were highly correlated (p < 0.01), and followed similar patterns of response. ISI-COMPEE was 71.4% higher than ISI-COMPB (8.4 ± 1.4 vs. 4.9 ± 1.0; p < 0.01) and 40.0% higher than ISI-COMPSIE (8.4 ± 1.4 vs. 6.0 ± 1.5; p < 0.05), but there was no difference between ISI-COMPB and ISI-COMPSIE (p = 0.182). VO2 peak was highly correlated with both ISI-COMP and ISI-HOMA during baseline and SIE test conditions (p < 0.02). These findings demonstrate that an acute bout of EE, but not SIE, increases insulin sensitivity relative to a no-exercise control condition in healthy males and females. While these findings underscore the use of regular EE as an effective intervention strategy against insulin resistance, additional research examining repeated sessions of SIE on insulin sensitivity is warranted.
Using simple anthropometric measures to predict body fat in South Asians
Authors: Kohli Simi , Gao Min , Lear Scott A. 
Published: February 2009

Previously determined predictive equations for body fat mass (BFM) are primarily derived from populations of European origin, which may not be appropriate for all ethnic groups. The objective of this study was to develop an improved predictive equation for BFM specific to South Asians and derived from common anthropometric measurements that include measures of central adiposity. A total of 208 apparently healthy South Asian men and women, aged 30–65 years, were recruited. Anthropometric measurements and BFM by dual energy X-ray absorbitometry (DEXA) were obtained. Sex-specific equations predicting BFM were developed using regression models on a reference subset (68 men, 70 women) and tested on a validation group. New predictive equations (BFMNEW) were tested for agreement with Durin and Wormersley and Siri equations and with the reference method, DEXA. The best predictive sex-specific equation involved a combination of skinfolds, waist circumference, hip circumference, humerus breadth, height, mass, and age. Models significantly correlated with BFM determined by DEXA (r = 0.946 for men; r = 0.974 for women; p < 0.001). The estimates of BFM from reference and validation groups had excellent correlations and displayed excellent agreement to DEXA measures. We demonstrated new predictive equations for BFM that are specific to South Asians and incorporate measures of central adiposity. This may help resolve issues surrounding inaccurate determination of adiposity in South Asians, and consequently provide better estimations of disease risk.
Effect of different models of physical exercise on oxidative stress markers in mouse liver
Authors: da Silva Luciano A. , Pinho Cleber A. , Rocha Luis G.C. , Tuon Talita , Silveira Paulo C.L. , Pinho Ricardo A. 
Published: February 2009

The aim of this study was to investigate the effect of different protocols of physical exercise on oxidative stress markers in mouse liver. Twenty-eight male CF1 mice (30–35 g) were distributed into 4 groups (n = 7) — untrained (UT), continuous running (CR), downhill running (D-HR), and intermittent running (IR) — and underwent an 8-week training program. Forty-eight hours after the last training session, the animals were killed, and their livers were removed. Blood lactate, creatine kinase, citrate synthase, thiobarbituric acid reactive species, carbonyl, superoxide dismutase (SOD), and catalase (CAT) activities were assayed. Results show a decrease in the level of lipoperoxidation and protein carbonylation in the CR and D-HR groups. SOD activity was significantly increased and CAT activity was reduced in the CR and D-HR groups. Our findings indicate that CR and D-HR may be important for decreasing oxidative damage and in the regulation of antioxidant enzymes (SOD and CAT) in the livers of trained mice.
Alpha-linolenic acid supplementation and resistance training in older adults
Authors: Cornish Stephen M. , Chilibeck Philip D. 
Published: February 2009

Increased inflammation with aging has been linked to sarcopenia. The purpose of this study was to evaluate the effects of supplementing older adults with alpha-linolenic acid (ALA) during a resistance training program, based on the hypothesis that ALA decreases the plasma concentration of the inflammatory cytokine tumor necrosis factor (TNF)-α and interleukin (IL)-6, which in turn would improve muscle size and strength. Fifty-one older adults (65.4 ± 0.8 years) were randomized to receive ALA in flax oil (~14 g·day–1) or placebo for 12 weeks while completing a resistance training program (3 days a week). Subjects were evaluated at baseline and after 12 weeks for muscle thickness of knee and elbow flexors and extensors (B-mode ultrasound), muscle strength (1 repetition maximum), body composition (dual energy X-ray absorptiometry), and concentrations of TNF-α and IL-6. Males supplementing with ALA decreased IL-6 concentration over the 12 weeks (62 ± 36% decrease; p = 0.003), with no other changes in inflammatory cytokines. Chest and leg press strength, lean tissue mass, muscle thickness, hip bone mineral content and density, and total bone mineral content significantly increased, and percent fat and total body mass decreased with training (p < 0.05), with the only benefit of ALA being a significantly greater increase in knee flexor muscle thickness in males (p < 0.05). Total-body bone mineral density improved in the placebo group, with no change in the ALA group (p = 0.05). ALA supplementation lowers the IL-6 concentration in older men but not women, but had minimal effect on muscle mass and strength during resistance training.
Improved endurance capacity following chocolate milk consumption compared with 2 commercially available sport drinks
Authors: Thomas Kevin , Morris Penelope , Stevenson Emma 
Published: February 2009

This study examined the effects of 3 recovery drinks on endurance performance following glycogen-depleting exercise. Nine trained male cyclists performed 3 experimental trials, in a randomized counter-balanced order, consisting of a glycogen-depleting trial, a 4-h recovery period, and a cycle to exhaustion at 70% power at maximal oxygen uptake. At 0 and 2 h into the recovery period, participants consumed chocolate milk (CM), a carbohydrate replacement drink (CR), or a fluid replacement drink (FR). Participants cycled 51% and 43% longer after ingesting CM (32 ± 11 min) than after ingesting CR (21 ± 8 min) or FR (23 ± 8 min). CM is an effective recovery aid after prolonged endurance exercise for subsequent exercise at low-moderate intensities.
Prefrontal cortex oxygenation is preserved and does not contribute to impaired neuromuscular activation during passive hyperthermia
Authors: Morrison Shawnda A. , Sleivert Gordon G. , Neary J. Patrick , Cheung Stephen S. 
Published: February 2009

We investigated the role of passive hyperthermia upon motor unit activation and prefrontal cortex oxygenation. Six healthy males were passively heated, using a liquid conditioning garment in a hot environment (35 °C, 50% relative humidity). Maximal force output and voluntary activation were examined during a 10 s maximal isometric knee extension. Of the initial 6 subjects, 1 experienced syncope at a rectal temperature (Tre) of 38.0 °C and was removed from the study. The remaining 5 subjects completed heating and testing to a Tre of 38.5 °C (n = 1), 39.0 °C (n = 3), or 39.5 °C (n = 1), and then were cooled back to baseline. Force production decreased from 553 ± 133 to 430 ± 176 N (p < 0.01) with passive heating, as did voluntary activation (from 90 ± 5% to 84 ± 7%). Percent heart rate reserve increased from 8 ± 5% to 59 ± 3% before returning to 4 ± 8% (p < 0.001). Although mean arterial pressure remained unchanged, there were significant decreases in diastolic blood pressure with heating (80 ± 3 to 63 ± 8 mm Hg). Passive heating did not alter prefrontal cortex oxygenation, but cooling back to baseline core temperature attenuated cerebral oxygenated and total hemoglobin levels (p < 0.05). Passive heating to the point of voluntary exhaustion elevated cardiovascular and thermal strain and subjective perceptions of thermal discomfort. However, while this resulted in a marked decrement in maximal isometric force production and central voluntary activation, no concomitant changes in cerebral oxygenation were observed, suggesting that overall cerebrovascular regulation was maintained.
Six years of plant community development after clearcut harvesting in western Washington
Authors: Peter David H. , Harrington Constance 
Published: February 2009

What roles do ruderals and residuals play in early forest succession and how does repeated disturbance affect them? We examined this question by monitoring plant cover and composition on a productive site for 6 years after clearcutting and planting Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco). The replicated experiment included three treatments: vegetation control with five annual herbicide applications superimposed over two levels of slash removal (bole only or total tree plus most other wood) and an untreated control. Three species groups were analyzed: native forest, native ruderals, and exotic ruderals. Without vegetation control, the understory was rapidly invaded by exotic ruderals but was codominated by native and exotic ruderals by year 6. Douglas-fir cover surpassed covers in the three species group covers at least 3 years sooner with herbicide treatments than without. Species richness and coverage were lower for all species groups with vegetation control than without vegetation control. The effects of organic matter removal were much less than that of vegetation control. As predicted by the Intermediate Disturbance Hypothesis, repeated vegetation control resulted in declining cover and richness; however, native forest species were surprisingly resilient, maintaining as much or more cover and richness as the ruderal groups.
Responses of insect pests, pathogens, and invasive plant species to climate change in the forests of northeastern North America: What can we predict?This article is one of a selection of papers from NE Forests 2100: A Synthesis of Climate Change Impacts on Forests of the Northeastern US and Eastern Canada.
Authors: Dukes Jeffrey S. , Pontius Jennifer , Orwig David , Garnas Jeffrey R. , Rodgers Vikki L. , Brazee Nicholas , Cooke Barry , Theoharides Kathleen A. , Stange Erik E. , Harrington Robin , Ehrenfeld Joan , Gurevitch Jessica , Lerdau Manuel , Stinson Kristina , Wick Robert , Ayres Matthew 
Published: February 2009

Climate models project that by 2100, the northeastern US and eastern Canada will warm by approximately 3–5 °C, with increased winter precipitation. These changes will affect trees directly and also indirectly through effects on “nuisance” species, such as insect pests, pathogens, and invasive plants. We review how basic ecological principles can be used to predict nuisance species’ responses to climate change and how this is likely to impact northeastern forests. We then examine in detail the potential responses of two pest species (hemlock woolly adelgid ( Adelges tsugae Annand) and forest tent caterpillar ( Malacosoma disstria Hubner)), two pathogens (armillaria root rot ( Armillaria spp.) and beech bark disease ( Cryptococcus fagisuga Lind. + Neonectria spp.)), and two invasive plant species (glossy buckthorn ( Frangula alnus Mill.) and oriental bittersweet ( Celastrus orbiculatus Thunb.)). Several of these species are likely to have stronger or more widespread effects on forest composition and structure under the projected climate. However, uncertainty pervades our predictions because we lack adequate data on the species and because some species depend on complex, incompletely understood, unstable relationships. While targeted research will increase our confidence in making predictions, some uncertainty will always persist. Therefore, we encourage policies that allow for this uncertainty by considering a wide range of possible scenarios.