bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evidence of pAgK84 transfer from Agrobacterium rhizogenes K84 to natural pathogenic Agrobacterium spp. in an Italian peach nursery
Authors: Raio A. , Peluso R. , Puopolo G. , Zoina A. 
Published: May 2009

Nine Italian peach nurseries, which use Agrobacterium rhizogenes strain K84 to protect plants from crown gall, were monitored for three years with the aim of determining whether transconjugant populations may arise following plasmid exchanges between K84 and autochtonous soil agrobacteria. Six hundred and seventy‐eight Agrobacterium isolates were obtained from 120 tumours developed on apricot and peach rootstocks that had been treated in pre‐planting with the antagonist. Agrobacteria were characterized for pathogenicity, biovar, opine catabolism and agrocin 84 sensitivity. Colony hybridization was used for screening the isolates harbouring plasmids pTi and/or pAgK84. Analysis of plasmid content and Southern blotting were performed on putative transconjugant agrobacteria found in tumours collected from one nursery where a biological control breakdown was observed. The RFLP analysis of 16S + IGS regions showed that pAgK84 was transferred from the antagonist to virulent and avirulent soil agrobacteria belonging to different ribotypes. Pathogenic transconjugants, inoculated on GF677 rootstocks, were not controlled in vivo by K84 and stably maintained pTi and pAgK84 in the bacterial cells for at least one year. At the end of a biocontrol trial, new transconjugant tumorigenic agrobacteria originated by the transfer of pAgK84 to the pathogen. Virulent and avirulent transconjugants may represent a real threat for biological control by K84 strain since all of them produced agrocin and were insensitive to it. Survival in soil of these populations could make the future application of K84 ineffective.
Evidence for hyperparasitism of coffee rust (Hemileia vastatrix) by the entomogenous fungus, Lecanicillium lecanii, through a complex ecological web
Authors: Vandermeer J. , Perfecto I. , Liere H. 
Published: May 2009

The entomogenous fungus, Lecanicillium lecanii is hyperparasitic on Hemileia vastatrix, the cause of coffee leaf rust in the laboratory, and has frequently been observed attacking it in the field. The existence of a complex ecological web involving the spatially clustered mutualism of an ant (Azteca instabilis) with a scale insect (Coccus viridis), where the scale insect was infected by L. lecanii, prompted a search for a spatial correlation between the attack of L. lecanii on the scale insect and the incidence of rust in a commercial coffee crop. A weak but statistically significant effect of hyperparasitic control of coffee rust was observed on two distinct scales: in a 45‐ha plot and on a scale of approximately 10 m. It was concluded that this effect was linked to an indirect effect of the ant–coccid mutualism, where L. lecanii was a parasite of the coccid.
Adaptation to an extraordinary environment by evolution of phenotypic plasticity and genetic assimilation
Authors: LANDE R. 
Published: May 2009

AbstractAdaptation to a sudden extreme change in environment, beyond the usual range of background environmental fluctuations, is analysed using a quantitative genetic model of phenotypic plasticity. Generations are discrete, with time lagτbetween a critical period for environmental influence on individual development and natural selection on adult phenotypes. The optimum phenotype, and genotypic norms of reaction, are linear functions of the environment. Reaction norm elevation and slope (plasticity) vary among genotypes. Initially, in the average background environment, the character is canalized with minimum genetic and phenotypic variance, and no correlation between reaction norm elevation and slope. The optimal plasticity is proportional to the predictability of environmental fluctuations over time lagτ. During the first generation in the new environment the mean fitness suddenly drops and the mean phenotype jumps towards the new optimum phenotype by plasticity. Subsequent adaptation occurs in two phases. Rapid evolution of increased plasticity allows the mean phenotype to closely approach the new optimum. The new phenotype then undergoes slow genetic assimilation, with reduction in plasticity compensated by genetic evolution of reaction norm elevation in the original environment.
The allometric pattern of sexually size dimorphic feather ornaments and factors affecting allometry
Authors: CUERVO J. J. , MØLLER A. P. 
Published: May 2009

AbstractThe static allometry of secondary sexual characters is currently subject to debate. While some studies suggest an almost universal positive allometry for such traits, but isometry or negative allometry for nonornamental traits, other studies maintain that any kind of allometric pattern is possible. Therefore, we investigated the allometry of sexually size dimorphic feather ornaments in 67 species of birds. We also studied the allometry of female feathers homologous to male ornaments (female ornaments in the following) and ordinary nonsexual traits. Allometries were estimated as reduced major axis slopes of trait length on tarsus length. Ornamental feathers showed positive allometric slopes in both sexes, although that was not a peculiarity for ornamental feathers, because nonsexual tail feathers also showed positive allometry. Migration distance (in males) and relative size of the tail ornament (in females) tended to be negatively related to the allometric slope of tail feather ornaments, although these results were not conclusive. Finally, we found an association between mating system and allometry of tail feather ornaments, with species with more intense sexual selection showing a smaller degree of allometry of tail ornaments. This study is consistent with theoretical models that predict no specific kind of allometric pattern for sexual and nonsexual characters.
Demographic history, geographical distribution and reproductive isolation of distinct lineages of blue rockfish (Sebastes mystinus), a marine fish with a high dispersal potential
Authors: BURFORD M. O. 
Published: May 2009

AbstractUnderstanding the barriers to genetic exchange in taxonomic groups that have a high dispersal potential will provide critical information on speciation in general. Blue rockfish (Sebastes mystinus) are good taxa to examine speciation because they are nonmigratory inhabitants of shallow rocky reef habitats along the eastern North Pacific with a pelagic larval stage lasting 3–5 months. The goal of this study was to analyse the evolutionary history and distribution patterns of different lineages withinS. mystinusdescribed previously and use this information to understand the speciation process in this group of high dispersal fish. The molecular data derived from specimens sampled over approximately 1650 km of theS. mystinusrange revealed a northerly and southerly distribution for the two lineages. Almost equal frequencies of both lineages occurred at centrally located sample locations, with evidence of reproductive isolation between the lineages. A demographic analysis showed that the two lineages diverged and experienced sudden expansion prior to the last glacial maximum, which affected the observed pattern of genetic structure. The spatial distribution, demographic history and degree of genetic distinctiveness found from the genetic analysis, despite the high potential for dispersal inS. mystinus, suggest both lineages diverged in allopatry.
Displacement of flowering phenologies among plant species by competition for generalist pollinators
Authors: DEVAUX C. , LANDE R. 
Published: May 2009

AbstractWe model the evolution of allochronic isolation between sympatric animal‐pollinated plant species via displacement of their flowering times. The plant species share generalist pollinators and either produce inviable hybrid seeds or do not hybridize at all. Displacement of flowering times between reproductively isolated species reduces competition for pollinators and the formation of inviable hybrid seeds. Under strong pollen limitation, competition for pollinators causes rapid evolution of allochronic isolation both for hybridizing and nonhybridizing species. Under weak pollen limitation, allochronic isolation evolves rapidly for hybridizing species but more slowly for nonhybridizing species. Positive density‐dependent pollinator visitation rate at low flower densities facilitates allochronic isolation under weak pollen limitation. Allochronic isolation among sympatric species sharing generalist pollinators could be common under any intensity of pollen limitation if the flowering season is sufficiently long.
Juniperus communis: victim of the combined action of climate warming and nitrogen deposition?
Authors: Verheyen K. , Adriaenssens S. , Gruwez R. , Michalczyk I. M. , Ward L. K. , Rosseel Y. , Van den Broeck A. , García D. 
Published: May 2009

AbstractResearch on the combined effects of climate change and nitrogen deposition on reproductive traits, and especially on the production of viable seeds, is still scarce despite their importance for population persistence and expansion. Hence, in this study we set out to investigate the direct and indirect effects of the above‐mentioned global change drivers on seed viability in the coniferous shrub Juniperus communis L. In many parts of its European range, juniper is increasingly threatened, partly because of a lack of sexual reproduction. We hypothesised that this regeneration failure is partly due to poor seed viability. Using data from 39 populations throughout Europe, we were able to demonstrate that a strong, triangular‐shaped relationship exists between the percentage of viable seeds produced and the percentage of juniper seedlings occurring in a population, which indicates that the species is indeed partly seed limited. Furthermore, based on an extended dataset of 42 populations, we found that seed viability was negatively affected by temperature, measured as mean annual growing degree‐days, and nitrogen deposition (but not by drought). Suggestions are made about the processes behind the observed patterns, but more research is required. Nevertheless, our results do raise serious concerns for the conservation of juniper in light of the predicted rise in temperature and global nitrogen emissions. Furthermore, it is likely that similar patterns can also be observed for other species.
Histology and Mucin Histochemistry of The Digestive Tract of Yellow Catfish, Pelteobagrus fulvidraco
Authors: Cao X. J. , Wang W. M. 
Published: May 2009

SummaryThe histology and characteristics of mucins secreted by epithelial mucous cells of the digestive tract in yellow catfish, Pelteobagrus fulvidraco were investigated using light microscope and transmission electron microscope. The digestive tract was divided into a pharynx, oesophagus, U‐shaped stomach (with a cardiac, fundic and pyloric part) and intestine, composed of anterior intestine, middle intestine and posterior intestine, which consisted of a mucosa (epithelial layer), lamina propria‐submucosa, muscularis and serosa. A large number of isolated longitudinal striated muscular bundles were present in the lamina propria‐submucosa of pharynx. Goblet cells were observed throughout the digestive tract, except in the stomach. In the cardiac and fundic stomach, a plenty of gastric glands were observed, whereas they were absent in the pyloric part. Numerous mitochondria and endoplasmic reticulum were observed in the columnar epithelial cells of the intestine, especially of the anterior part. The epithelial mucous cells contained neutral or other two mixtures of acid and neutral mucins, the first being the most common. The neutral mucin was the only type of mucins in the stomach, anterior intestine and middle intestine. The results of this study will be helpful for understanding the digestive physiology and diagnosing some gastrointestinal diseases in yellow catfish.
Rudimentary Coronary Artery in Syrian Hamsters (Mesocricetus auratus)
Authors: Durán A. C. , Arqué J. M. , Fernández B. , Fernández M. C. , Fernández‐Gallego T. , Rodríguez C. , Sans‐Coma V. 
Published: May 2009

SummaryCongenital underdevelopment of one or more main branches of the coronary arteries has been reported in man, but not in non‐human mammals. In man, this defective coronary artery arrangement may cause myocardial ischaemia and even sudden death.The main goal of this study was to describe the coronary artery distribution patterns associated with the presence of a markedly underdeveloped (rudimentary) coronary artery in Syrian hamsters. Moreover, an attempt was made to explain the morphogenesis of these patterns, according to current knowledge on coronary artery development. Eleven affected hamsters belonging to a laboratory inbred family were examined by means of internal casts of the heart, great arterial trunks and coronary arteries. The aortic valve was tricuspid (normal) in seven hamsters and bicuspid in the other four. A rudimentary coronary artery arose from the right side of the aortic valve in four specimens, from the left side of the aortic valve in a further three, and from the dorsal aortic sinus in the remaining four. In all cases, a second, well‐developed coronary artery provided for all the coronary blood flow. Except for the existence of a rudimentary coronary artery, the present anomalous coronary artery distribution patterns are similar to coronary artery patterns reported in Syrian hamsters, dogs and humans in association with a solitary coronary ostium in aorta. We suggest that an unusual prolonged time interval in the development of the embryonic coronary stems might be a key factor in the formation of coronary arteries displaying significantly dissimilar developmental degrees.
Phase variation, capsular polysaccharide, pilus and flagella contribute to uptake of Vibrio vulnificus by the Eastern oyster (Crassostrea virginica)
Authors: Srivastava Milan , Tucker Matthew S. , Gulig Paul A. , Wright Anita C. 
Published: May 2009

Summary Vibrio vulnificus infections are associated with raw oyster consumption, and disease reservoirs are determined by the ability of this bacterium to infect and persist in oysters. Surface structures, such as capsular polysaccharide (CPS), pili and flagella, function as virulence factors in mouse infection models. Furthermore, virulence is related to phase variation in colony morphology, which reflects CPS expression and includes opaque (encapsulated, virulent), translucent (reduced encapsulation, avirulent) and rugose (wrinkled, biofilm‐enhanced) colony types. The role of these factors in environmental survival is unknown; therefore, mutational analysis and phase variation of V. vulnificus were examined in an oyster infection model. Oysters (Crassostrea virginica) were pre‐treated with tetracycline to reduce background bacteria and subsequently inoculated via filter feeding with 106 colony‐forming units (cfu) ml−1 of V. vulnificus wild‐type strains and phase variants, as well as strains with deletion mutations in genes related to CPS (Δwza), pili (ΔpilA), flagella (ΔflaCDE/ΔflaFBA) and motility (ΔmotAB). All mutants were significantly reduced in their dissemination to oyster haemolymph as compared with wild type; however, recovery of mutants from gills and intestinal tissue was generally similar to wild type. Translucent and rugose inocula showed induction of high‐frequency phase variation to the opaque encapsulated phenotype (100% and 72% respectively) during oyster infections that did not occur in strains recovered from seawater. Thus, multiple bacterial factors determine uptake of V. vulnificus in oysters, and phase variation during oyster infection is a likely mechanism for environmental survival and for induction of the more virulent phenotype.
Saxagliptin given in combination with metformin as initial therapy improves glycaemic control in patients with type 2 diabetes compared with either monotherapy: a randomized controlled trial
Authors: Jadzinsky M. , Pfützner A. , Paz‐Pacheco E. , Xu Z. , Allen E. , Chen R. ,   CV181‐039 Investigators
Published: May 2009

Aim:  The study aim was to evaluate the efficacy and safety of initial combination therapy with saxagliptin + metformin vs. saxagliptin or metformin monotherapy in treatment‐naïve patients with type 2 diabetes (T2D) and inadequate glycaemic control.Methods:  In this multicentre, randomized, double‐blind, active‐controlled phase 3 trial, 1306 treatment‐naïve patients with T2D ≥18 to ≤77 years, glycosylated haemoglobin (HbA1c) ≥8 to ≤12%, fasting C‐peptide concentration ≥1.0 ng/ml, body mass index ≤40 kg/m2 were randomized to receive saxagliptin 5 mg + metformin 500 mg, saxagliptin 10 mg + metformin 500 mg, saxagliptin 10 mg + placebo or metformin 500 mg + placebo for 24 weeks. From weeks 1–5, metformin was uptitrated in 500‐mg/day increments to 2000 mg/day maximum in the saxagliptin 5 mg + metformin, saxagliptin 10 mg + metformin and metformin + placebo treatment groups. The main outcome measure was HbA1c change from baseline to week 24. Selected secondary outcomes included change from baseline to week 24 in fasting plasma glucose (FPG), proportion of patients achieving HbA1c <7% and postprandial glucose area under the curve (PPG‐AUC).Results:  At 24 weeks, saxagliptin 5 mg + metformin and saxagliptin 10 mg + metformin demonstrated statistically significant adjusted mean decreases vs. saxagliptin 10 mg and metformin monotherapies in HbA1c (−2.5 and −2.5% vs. −1.7 and −2.0%, all p < 0.0001 vs. monotherapy) and FPG (−60 and −62 mg/dl vs. −31 and −47 mg/dl, both p < 0.0001 vs. saxagliptin 10 mg; p = 0.0002 saxagliptin 5 mg + metformin vs. metformin; p < 0.0001 saxagliptin 10 mg + metformin vs. metformin). Proportion of patients achieving an HbA1c <7% was 60.3 and 59.7%, respectively, for saxagliptin 5 mg + metformin and saxagliptin 10 mg + metformin (all p < 0.0001 vs. monotherapy). PPG‐AUC was significantly reduced [−21 080 mg·min/dl (saxagliptin 5 mg + metformin) and −21 336 mg·min/dl (saxagliptin 10 mg + metformin) vs. −16 054 mg·min/dl (saxagliptin 10 mg) and −15 005 mg·min/dl (metformin), all p < 0.0001 vs. monotherapy]. Adverse event occurrence was similar across all groups. Hypoglycaemic events were infrequent.Conclusion:  Saxagliptin + metformin as initial therapy led to statistically significant improvements compared with either treatment alone across key glycaemic parameters with a tolerability profile similar to the monotherapy components.
REAL EXCHANGE RATE, DISTRIBUTION AND MACRO FLUCTUATIONS IN EXPORT‐ORIENTED ECONOMIES
Authors: La Marca Massimiliano 
Published: May 2009

ABSTRACTThe paper investigates the emergence of alternative growth, distribution and real exchange rate patterns as outcomes of institutional and socio‐economic interactions between broadly defined actors in an export‐oriented economy. The focus is on both the long‐run configuration and short‐run dynamics of the real exchange rate, the profit and wage shares, output growth, capacity utilization, and net foreign asset accumulation in a stock‐flow consistent framework with fiscal polices affecting the internal and external equilibrium. Fluctuations in output and distribution between income shares and the real exchange rate are obtained via Structuralist‐Goodwin dynamics.
Sub‐optimal CD4 recovery on long‐term suppressive highly active antiretroviral therapy is associated with favourable outcome
Authors: Önen NF , Overton ET , Presti R , Blair C , Powderly WG , Mondy K 
Published: May 2009

Objectives
To examine risk factors for sub‐optimal CD4 recovery on suppressive highly active antiretroviral therapy (HAART) and assess long‐term clinical and immunological outcomes.Methods
Retrospective analysis of 286 HIV‐positive patients from a university clinic who initiated HAART with CD4 count <350 cells/μL between January 1996 and July 2006 and achieved ≥52 weeks of viral suppression (VS). Sub‐optimal and optimal CD4 count recovery were defined by gains of <150 and ≥150 cells/μL during the first year of VS, respectively. Risk factors were analysed by multivariate logistic regression and markers of immune maturation and activation were evaluated prospectively for a sub‐group of patients with prolonged (>5 years) VS.Results
One hundred and two (36%) patients had sub‐optimal CD4 recovery. Male gender, lower pre‐HAART viral load, HAART toxicity and use of opportunistic infection (OI) prophylaxis were independent risk factors on multivariate analysis (P<0.05). Outcomes of duration of VS on HAART (4 years), new OI events (1%) and mortality (5%) were similar between groups. Markers of immune maturation and activation were higher among patients with sub‐optimal CD4 recovery (P<0.05).Conclusions
Among HIV‐positive patients with long‐term VS, sub‐optimal CD4 recovery was common but morbidity and mortality remained low. In addition, persistent CD4 T‐cell activation appeared to blunt long‐term CD4 gains.
Cryptogenic liver disease in HIV‐seropositive men
Authors: Dinh MH , Stosor V , Rao SM , Miller FH , Green RM 
Published: May 2009

Objectives
In the era of highly active antiretroviral therapy (HAART), liver disease has become a leading cause of morbidity and mortality in HIV‐seropositive individuals. Although liver disease is commonly caused by viral co‐infection, it has also been described in patients without viral hepatitis. In this study, we determined clinical factors associated with the development of cryptogenic liver disease in HIV‐infected individuals.Methods
HIV‐seropositive and ‐seronegative patients undergoing evaluation for liver transplantation were selected if they met clinical criteria for cryptogenic liver disease. Clinical data were collected retrospectively, and radiological and histological data were reviewed separately.Results
Nine HIV‐seropositive individuals were compared with 41 HIV‐seronegative patients with cryptogenic liver disease. Only one HIV‐seropositive patient (11%) had cirrhosis, compared to 39 HIV‐seronegative patients (93%) (P<0.001). Three HIV‐infected patients (33%) had histological evidence of nodular regenerative hyperplasia. HIV‐seropositive patients had significantly lower body mass indices, and lower Child–Pugh–Turcotte and Model for Endstage Liver Disease scores than HIV‐seronegative patients (P<0.05).Conclusions
Advanced cryptogenic liver disease in HIV‐infected patients is infrequently caused by cirrhosis, and more frequently by nodular regenerative hyperplasia. This disease entity may become more common in the HAART era, and may contribute to an increased morbidity in HIV‐infected individuals.