bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of six European tree species and land‐use legacy for nitrogen and water budgets in forests
Authors: CHRISTIANSEN JESPER RIIS , VESTERDAL LARS , CALLESEN INGEBORG , ELBERLING BO , SCHMIDT INGER KAPPEL , GUNDERSEN PER 
Published: September 2009

AbstractWater and nutrient fluxes for single stands of different tree species have been reported in numerous studies, but comparative studies of nutrient and hydrological budgets of common European deciduous tree species are rare. Annual fluxes of water and inorganic nitrogen (N) were established in a 30‐year‐old common garden design with stands of common ash (Fraxinus excelsior), European beech (Fagus sylvatica L.), pedunculate oak (Quercus robur), small‐leaved lime (Tilia cordata Mill.), sycamore maple (Acer pseudoplatanus) and Norway spruce (Picea abies [L.] Karst.) replicated at two sites in Denmark, Mattrup and Vallø during 2 years. Mean annual percolation below the root zone (mm yr−1±SE, n=4) ranked in the following order: maple (351±38)>lime (284±32), oak (271±25), beech (257±30), ash (307±69)≫ spruce (75±24). There were few significant tree species effects on N fluxes. However, the annual mean N throughfall flux (kg N ha−1 yr−1±SE, n=4) for spruce (28±2) was significantly larger than for maple (12±1), beech (11±1) and oak (9±1) stands but not different from that of lime (15±3). Ash had a low mean annual inorganic N throughfall deposition of 9.1 kg ha−1, but was only present at Mattrup. Annual mean of inorganic N leaching (kg ha−1 yr−1±SE, n=4) did not differ significantly between species despite of contrasting tree species mean values; beech (25±9)>oak (16±10), spruce (15±8), lime (14±8)≫ maple (1.9±1), ash (2.0±1). The two sites had similar throughfall N fluxes, whereas the annual leaching of N was significantly higher at Mattrup than at Vallø. Accordingly, the sites differed in soil properties in relation to rates and dynamics of N cycling. We conclude that tree species affect the N cycle differently but the legacy of land use exerted a dominant control on the N cycle within the short‐term perspective (30 years) of these stands.
Associations of leaf miners and leaf gallers with island plants of different residency histories
Authors: Sugiura Shinji 
Published: September 2009

AbstractAim  Introduced plant species are less likely to be attacked by herbivores than are native plant species. Isolated oceanic islands provide an excellent model system for comparing the associations between herbivore species and plant species of different residency histories, namely endemic, indigenous (non‐endemic) or introduced (naturalized or cultivated) species. My aim was to test the prediction that, on isolated oceanic islands, introduced plant species have a lower tendency to have an association with insect herbivores than do endemic and indigenous plant species.Location  Ogasawara (Bonin) Islands in the western Pacific Ocean.Methods  I examined the presence/absence of leaf‐mining and leaf‐galling insect species on 71 endemic, 31 indigenous, 18 naturalized and 31 cultivated (introduced but not naturalized) species of woody plants from 2004 to 2008.Results  Leaf‐mining insect species were found on 53.5%, 35.5%, 11.1% and 16.1% and leaf‐galling species were found on 14.1%, 9.7%, 5.6% and 0% of endemic, indigenous, naturalized and cultivated plant species, respectively. Species of Lepidoptera (moths) and Hemiptera (primarily psyllids) comprised the dominant types of leaf miners and leaf gallers, respectively.Main conclusions  The incidence of leaf miners and leaf gallers differed as a function of residency history of the plant species. Introduced (naturalized and cultivated) species were less frequently associated with leaf miners and leaf gallers than were native (endemic and indigenous) species, indicating that the leaf‐mining and leaf‐galling insect species, most of which feed on leaves of a particular native plant genus (i.e. they show oligophagy), have not yet begun to utilize most introduced plant species.
Geographic limits of a clonal population of wheat yellow rust in the Mediterranean region
Authors: BAHRI B. , LECONTE M. , OUFFROUKH A. , DE VALLAVIEILLE‐POPE C. , ENJALBERT J. 
Published: September 2009

AbstractMost plant pathogens present complex life cycles, in which the clonal reproduction may impede the delimitation of population entities. By studying the genetic structure of the wheat yellow rust caused by Puccinia striiformis f.sp. tritici (PST), we highlighted difficulties impeding population delimitation in highly clonal species. Despite the high dispersal potential of PST, southern France isolates were shown to be divergent from a northwestern European population. A 2‐year survey was performed in the Mediterranean region to assess the geographic distribution of southern isolates: 453 isolates collected in 11 countries were genotyped using 15 simple sequence repeat markers. A subsample was analysed for virulence against 23 resistance genes. The dominant strain in the western Mediterranean region was further studied with amplified fragment length polymorphism markers to test for a geographic substructure. Both ‘individual’‐ and ‘population’‐centred analyses of polymorphism markers revealed two south‐specific groups: a predominant group, with a broad variability and a wide distribution in both western and eastern Mediterranean countries, and a minor group in the western Mediterranean. The east–west gradient of genetic diversity suggested gene flow from the Middle East with subsequent founder effects and genetic divergence, and demonstrated the local survival of a western Mediterranean population. The high frequency of the resistance gene Yr8 observed in cultivars from Tunisia and Algeria may contribute to maintain the north/south structure observed in France. In addition to migration and local adaptation, the dynamics of clonal lineage diversification and replacement should be considered to define population entities in strongly clonal species.
Comparison of contemporary mating patterns in continuous and fragmented Eucalyptus globulus native forests
Authors: MIMURA MAKIKO , BARBOUR ROBERT C. , POTTS BRAD M. , VAILLANCOURT RENÉ E. , WATANABE KAZUO N. 
Published: September 2009

AbstractWhile habitat fragmentation is a central issue in forest conservation studies in the face of broad‐scale anthropogenic changes to the environment, its effects on contemporary mating patterns remain controversial. This is partly because of the inherent variation in mating patterns which may exist within species and the fact that few studies have replication at the landscape level. To study the effect of forest fragmentation on contemporary mating patterns, including effective pollen dispersal, we compared four native populations of the Australian forest tree, Eucalyptus globulus. We used six microsatellite markers to genotype 1289 open‐pollinated offspring from paired fragmented and continuous populations on the island of Tasmania and in Victoria on mainland Australia. The mating patterns in the two continuous populations were similar, despite large differences in population density. In contrast, the two fragmented populations were variable and idiosyncratic in their mating patterns, particularly in their pollen dispersal kernels. The continuous populations showed relatively high outcrossing rates (86–89%) and low correlated paternity (0.03–0.06) compared with the fragmented populations (65–79% and 0.12–0.20 respectively). A greater proportion of trees contributed to reproduction in the fragmented (de/d≥ 0.5) compared with the continuous populations (de/d = 0.03–0.04). Despite significant inbreeding in the offspring of the fragmented populations, there was little evidence of loss of genetic diversity. It is argued that enhanced medium‐ and long‐distance dispersal in fragmented landscapes may act to partly buffer the remnant populations from the negative effects of inbreeding and drift.
Female philopatry in coastal basins and male dispersion across the North Atlantic in a highly mobile marine species, the sperm whale (Physeter macrocephalus)
Authors: ENGELHAUPT DANIEL , RUS HOELZEL A. , NICHOLSON COLIN , FRANTZIS ALEXANDROS , MESNICK SARAH , GERO SHANE , WHITEHEAD HAL , RENDELL LUKE , MILLER PATRICK , DE STEFANIS RENAUD , CAÑADAS ANA , AIROLDI SABINA , MIGNUCCI‐GIANNONI ANTONIO A. 
Published: September 2009

AbstractThe mechanisms that determine population structure in highly mobile marine species are poorly understood, but useful towards understanding the evolution of diversity, and essential for effective conservation and management. In this study, we compare putative sperm whale populations located in the Gulf of Mexico, western North Atlantic, Mediterranean Sea and North Sea using mtDNA control region sequence data and 16 polymorphic microsatellite loci. The Gulf of Mexico, western North Atlantic and North Sea populations each possessed similar low levels of haplotype and nucleotide diversity at the mtDNA locus, while the Mediterranean Sea population showed no detectable mtDNA diversity. Mitochondrial DNA results showed significant differentiation between all populations, while microsatellites showed significant differentiation only for comparisons with the Mediterranean Sea, and at a much lower level than seen for mtDNA. Samples from either side of the North Atlantic in coastal waters showed no differentiation for mtDNA, while North Atlantic samples from just outside the Gulf of Mexico (the western North Atlantic sample) were highly differentiated from samples within the Gulf at this locus. Our analyses indicate a previously unknown fidelity of females to coastal basins either side of the North Atlantic, and suggest the movement of males among these populations for breeding.
Genetic variation and local adaptation at a cheatgrass (Bromus tectorum) invasion edge in western Nevada
Authors: LEGER ELIZABETH A. , ESPELAND ERIN K. , MERRILL KEITH R. , MEYER SUSAN E. 
Published: September 2009

AbstractCheatgrass (Bromus tectorum) is an invasive weed in western North America found primarily growing at elevations less than 2200 m. We asked whether cheatgrass is capable of becoming adapted to a marginal habitat, by investigating a population at a high elevation invasion edge. We used a combination of methods, including reciprocal field transplants, controlled environment studies and molecular analysis. High levels of SSR gene diversity (0.50 vs. 0.43) and comparable variation in phenotypic traits were observed at both the invasion edge and a low elevation, high‐density population. Three heterozygotes were observed in the edge population, which is unusual in this predominantly self‐pollinating plant. Plants from high elevations germinated more slowly in a growth chamber and had slower seedling growth rates. Survivorship was low at the edge (13%), compared with the low elevation site (55%), but surviving plants were of similar size and had equivalent reproductive output. Seed size positively affected survival and plant performance in the field and this trait was inherited. Emergence timing affected survival at the low elevation site and germination timing was also inherited. Local adaptation was seen in the low, rather than in the high elevation site, because of differential survival. While there was no evidence for local adaptation to the high elevation site observed in the field, family level and genotype‐level differences in traits that affected field performance, high genetic diversity at the invasion edge, and evidence of outcrossing in this highly selfing species indicates that the potential for adaptation to a marginal habitat exists within this population.
Concordant genetic breaks, identified by combining clustering and tessellation methods, in two co‐distributed alpine plant species
Authors: THIEL‐EGENTER CONNY , HOLDEREGGER ROLF , BRODBECK SABINE ,   INTRABIODIV CONSORTIUM, GUGERLI FELIX 
Published: September 2009

AbstractNatural genetic breaks may indicate limitations to gene flow or the presence of contact zones of previously isolated populations. Molecular evidence suggests that genetic breaks have aggregated in distinct geographical areas. We propose a new application of well‐established statistical methods for analysing multilocus genetic data to identify intraspecific genetic breaks. The methodological approach combines Bayesian clustering with a spatially explicit maximum‐difference algorithm to visualize and quantify breaks between clusters. We used amplified fragment length polymorphism data of two co‐distributed, silicicolous alpine plant species, Geum montanum and Geum reptans, exhaustively sampled on a consistent, regular grid over their entire range of the European Alps and the Carpathians. We found a distinct and highly similar allocation of genetic breaks in both species. The pattern of breaks did not conform to scenarios of glacial refugial survival, alternatively in peripheral refugia or on nunataks, as expected because of the species’ ecologies (late‐successional low alpine vs. early‐successional high alpine). Our findings rather substantiated the postulate of a general pattern of genetic breaks in alpine plants and corresponded well with biogeographical regions formerly described. Our approach could serve as a tool not only for landscape genetics and comparative phylogeography, but also for floristics or faunistics to compare biogeographic with phylogeographic breaks.
Hydrogen sulphide protects H9c2 cells against chemical hypoxia‐induced injury
Authors: Chen Si‐Lin , Yang Chun‐Tao , Yang Zhan‐Li , Guo Rui‐Xian , Meng Jin‐Lan , Cui Yu , Lan Ai‐Ping , Chen Pei‐Xi , Feng Jian‐Qiang 
Published: September 2009

Summary1. The aim of the present study was to investigate the effect of hydrogen sulphide (H2S) on cobalt chloride (CoCl2)‐induced injury in H9c2 embryonic rat cardiac cells.2. After 36 h incubation in the presence of 600 μmol/L CoCl2, reduced cell viability of H9c2 cells was observed, as well as the induction of apoptosis. In addition, CoCl2 (600 μmol/L) enhanced the production of reactive oxygen species (ROS) and the expression of cleaved caspase 3, induced a loss of mitochondrial membrane potential (MMP) and decreased reduced glutathione (GSH) production. These results suggest that CoCl2 induces similar responses to hypoxia/ischaemia.3. Pretreatment of cells with 400 μmol/L NaHS (a H2S donor) for 30 min prior to exposure to CoCl2 (600 μmol/L) significantly protected H9c2 cells against CoCl2‐induced injury. Specifically, increased cell viability and decreased apoptosis were observed. In addition, NaHS pretreatment blocked the CoCl2‐induced increases in ROS production and cleaved caspase 3 expression, as well as the decreases in GSH production and loss of MMP.4. Pretreatment of cells with 2000 μmol/L N‐acetylcysteine (NAC), a ROS scavenger, for 1 h prior to CoCl2 exposure significantly protected H9c2 cells against CoCl2‐induced injury, specifically enhancing cell viability, decreasing ROS production and preventing loss of MMP.5. The findings of the present study suggest that H2S protects H9c2 cells against CoCl2‐induced injury by suppressing oxidative stress and caspase 3 activation.
(Pro)renin receptor contributes to diabetic nephropathy by enhancing renal inflammation
Authors: Matavelli Luis C , Huang Jiqian , Siragy Helmy M 
Published: September 2009

Summary1. (Pro)renin receptor (PRR) binding to renin or prorenin mediates angiotensin (Ang) II‐dependent and ‐independent effects. Expression of the PRR is increased in kidneys of diabetic rats, but its role in diabetic nephropathy is unknown. In the present study, we investigated the contribution of the PRR to the development of diabetic nephropathy through enhancement of renal production of tumour necrosis factor (TNF)‐α and interleukin (IL)‐1β.2. Normoglycaemic control and streptozotocin‐diabetic Sprague‐Dawley rats were used in the study. The urine albumin : creatinine ratio (UACR), renal interstitial fluid (RIF) levels of AngII, TNF‐α and IL‐1β and renal expression of TNF‐α and IL‐1β were evaluated in control, untreated diabetic and diabetic rats treated with either a PRR blocker (PRRB; 0.2 mg/kg per day NH3‐RILLKKMPSV‐COOH), the AT1 receptor antagonist valsartan (2 mg/kg per day) or combined therapy, administered directly into the renal cortical interstitium for 14 days via osmotic minipumps.3. Compared with values in normoglycaemic control rats, UACR and RIF AngII, TNF‐α and IL‐1β were significantly higher in untreated diabetic rats. Treatment of diabetic rats with the PRRB or valsartan alone and in combination significantly reduced UACR and RIF TNF‐α and IL‐1β levels. Renal expression of TNF‐α and IL‐1β was higher in untreated diabetic rats than in control rats, but was reduced significantly following treatment with PRRB or valsartan alone and in combination. Renal PRR expression was increased in untreated and PRRB‐treated diabetic rats and reduced in rats receiving valsartan alone or combination therapy. The PRRB had no effect on RIF AngII levels, whereas valsartan alone and in combination with the PRRB significantly increased AngII levels.4. In conclusion, the PRR is involved in the development and progression of kidney disease in diabetes by enhancing renal production of the inflammatory cytokines TNF‐α and IL‐1β, independent of renal AngII effects.
Central and baroreflex control of heart period during the wake–sleep cycle in consomic rats with different genetic susceptibility to hypertension
Authors: Silvani Alessandro , Bastianini Stefano , Berteotti Chiara , Franzini Carlo , Lenzi Pierluigi , Martire Viviana Lo , Zoccoli Giovanna 
Published: September 2009

Summary1. In spontaneously hypertensive rats (SHR), the contributions of the baroreflex and central autonomic commands to the control of heart period (HP) vary among wake–sleep states and are impaired during quiet wakefulness and rapid eye movement sleep (REMS), respectively.2. Dahl salt‐sensitive (SS) rats are genetically susceptible to salt‐sensitive hypertension, the development of which depends on diet. Substitution of chromosome 13 of SS rats with that of Brown Norway rats confers salt‐resistance to consomic SS‐13BN rats.3. In the present study, we tested whether differences in the central and baroreflex contributions to HP control occur among wake–sleep states in SS and SS‐13BN rats and reflect genetic susceptibility to hypertension. Rats (n = 5 per group) were fed a prohypertensive diet late during development to minimize hypertension in SS rats and were instrumented with an arterial catheter and electrodes for discriminating wake–sleep states.4. The cross‐correlation function between HP and blood pressure indicated that, in SS and SS‐13BN rats, the contributions of the baroreflex and central commands to the control of HP differed significantly among wake–sleep states, with central commands outweighing the baroreflex in REMS. However, these contributions did not differ significantly between SS and SS‐13BN rats in any wake–sleep state.5. The data suggest that differences in the central and baroreflex contributions to HP control among wake–sleep states, which have been demonstrated in SHR, can be generalized to other rat models used in hypertension research. Impairments in the baroreflex and central autonomic control of HP during quiet wakefulness and REMS, respectively, cannot be generalized as an index of genetic susceptibility to hypertension.
Proteinase‐activated receptor‐2 (PAR2) and mouse osteoblasts: Regulation of cell function and lack of specificity of PAR2‐activating peptides
Authors: Georgy Smitha R , Pagel Charles N , Wong David M , Sivagurunathan Sutharshani , Loh Lay H , Myers Damian E , Hollenberg Morley D , Pike Robert N , Mackie Eleanor J 
Published: September 2009

Summary1. Using synthetic proteinase‐activated receptor‐2 (PAR2)‐activating peptides (PAR2APs) corresponding to the tethered ligand domain of the extracellular N‐terminus of PAR2to mimic the actions of activating proteinases and using primary cultures of calvarial osteoblasts derived from both wild‐type (WT) and PAR2‐null (KO) mice, we investigated the potential role of PAR2in regulating osteoblast function.2. Primary calvarial osteoblasts from WT and KO mice were evaluated for their growth kinetics and mineralization in the absence of PAR2agonists and for their responses in a variety of functional assays to the PAR2APs Ser‐Leu‐Ile‐Gly‐Arg‐Leu‐amide (SLIGRL‐NH2) and 2‐furoyl‐Leu‐Ile‐Gly‐Arg‐Leu‐Orn‐amide (2‐fLIGRLO‐NH2), as well as to trypsin.3. In contrast with WT cells, PAR2‐KO osteoblasts did not exhibit increased collagen Type I mRNA expression in response to SLIGRL‐NH2. When grown in serum‐containing medium, KO cells increased in number more rapidly than WT cells, an effect that could be attributed to decreased apoptosis rather than increased proliferation. Surprisingly, in both WT and KO osteoblasts, the two PAR2APs induced mobilization of intracellular calcium stores. Similarly, the PAR2APs inhibited serum deprivation‐induced apoptosis and parathyroid hormone‐, 1,25‐dihydroxyvitamin D3‐ or interleukin‐11‐induced mineralization in WT and KO cells.4. We conclude that PAR2plays a role in osteoblast survival and collagen Type I mRNA induction and that osteoblasts can respond to the PAR2APs via both PAR2‐dependent and ‐independent mechanisms.
Effect of antihypertensive drug therapy on short‐term heart rate variability in newly diagnosed essential hypertension
Authors: Pavithran Purushothaman , Prakash E Sankaranarayanan , Dutta Tarun K , Madanmohan Trakroo 
Published: September 2009

Summary1. Abnormalities of cardiac autonomic regulation are a potential mechanism for morbidity despite blood pressure (BP) lowering in hypertension. Analysis of short‐term (5 min) heart rate variability (HRV) provides a non‐invasive probe of autonomic regulation of sino‐atrial (SA) node automaticity.2. We hypothesized that antihypertensive drug therapy would be associated with an increase in 5 min overall HRV, along with a decrease in blood pressure (BP), at 8 weeks follow up in subjects with newly diagnosed, never‐treated essential hypertension.3. One hundred and fifty patients (84 men and 66 women; mean (±SD) age 48 ± 10 years) with newly diagnosed essential hypertension were divided to five groups of 30 patients each to receive one of the following antihypertensive drugs (or drug combinations): 5 mg/day amlodipine; 50 mg/day atenolol; 5 mg/day enalapril; 25 mg/day hydrochlorothiazide; or a combination of 5 mg/day amlodipine and 50 mg/day atenolol.4. The only significant change in HRV indices was an increase in total variability of RR intervals and an increase in high‐frequency (HF) RR interval spectral power in the amlodipine + atenolol‐treated group (P < 0.05).5. The results indicate that there is a dissociation between changes in short‐term HRV and mean RR interval and BP lowering in patients with newly diagnosed hypertension.6. We interpret the increase in HF RR interval spectral power in the amlodipine + atenolol‐treated group as being due to an increase in vagal modulation of RR intervals and/or diminution in sympathetic restraint of respiratory sinus arrhythmia.
Secretory control: Evidence for agonist regulation of post‐fusion vesicle behaviour
Authors: Soekmadji Carolina , Thorn Peter 
Published: September 2009

Summary1. Here, we review recent work on vesicular secretion, with a focus on the control of post‐fusion events as a means of regulating secretory output.2. In the classical model of secretion, each fused vesicle releases the entirety of its content in an all‐or‐none manner. In this way, the secretory output of a cell is controlled by regulating the numbers of fused vesicles. The realisation that post‐fusion events can control secretory output leads to a distinct model of partial release of vesicle content.3. Recent work shows that post‐fusion events are under cellular control. Further, new data from our laboratory demonstrates agonist‐dependent regulation of fusion pore behaviour.4. We conclude that post‐fusion events are not epiphenomena, but are likely an important mechanism of secretory control.