bluuebunny/crossref_metadata_2025 huggingface dataset:
Tomato yellow leaf curl viruses: ménage à trois between the virus complex, the plant and the whitefly vector
Authors: DÍAZ‐PENDÓN JUAN ANTONIO , CAÑIZARES M. CARMEN , MORIONES ENRIQUE , BEJARANO EDUARDO R. , CZOSNEK HENRYK , NAVAS‐CASTILLO JESÚS
Published: March 2010

Tomato yellow leaf curl disease (TYLCD) is one of the most devastating viral diseases affecting tomato crops in tropical, subtropical and temperate regions of the world. Here, we focus on the interactions through recombination between the different begomovirus species causing TYLCD, provide an overview of the interactions with the cellular genes involved in viral replication, and highlight recent progress on the relationships between these viruses and their vector, the whitefly Bemisia tabaci.

Taxonomy:  The tomato yellow leaf curl virus‐like viruses (TYLCVs) are a complex of begomoviruses (family Geminiviridae, genus Begomovirus) including 10 accepted species: Tomato yellow leaf curl Axarquia virus (TYLCAxV), Tomato yellow leaf curl China virus (TYLCCNV), Tomato yellow leaf curl Guangdong virus (TYLCGuV), Tomato yellow leaf curl Indonesia virus (TYLCIDV), Tomato yellow leaf curl Kanchanaburi virus (TYLVKaV), Tomato yellow leaf curl Malaga virus (TYLCMalV), Tomato yellow leaf curl Mali virus (TYLCMLV), Tomato yellow leaf curl Sardinia virus (TYLCSV), Tomato yellow leaf curl Thailand virus (TYLCTHV), Tomato yellow leaf curl Vietnam virus (TYLCVNV) and Tomato yellow leaf curl virus(TYLCV). We follow the species demarcation criteria of the International Committee on Taxonomy of Viruses (ICTV), the most important of which is an 89% nucleotide identity threshold between full‐length DNA‐A component nucleotide sequences for begomovirus species. Strains of a species are defined by a 93% nucleotide identity threshold.

Host range:  The primary host of TYLCVs is tomato (Solanum lycopersicum), but they can also naturally infect other crops [common bean (Phaseolus vulgaris), sweet pepper (Capsicum annuum), chilli pepper (C. chinense) and tobacco (Nicotiana tabacum)], a number of ornamentals [petunia (Petunia×hybrida) and lisianthus (Eustoma grandiflora)], as well as common weeds (Solanum nigrum and Datura stramonium). TYLCVs also infect the experimental host Nicotiana benthamiana.

Disease symptoms:  Infected tomato plants are stunted or dwarfed, with leaflets rolled upwards and inwards; young leaves are slightly chlorotic; in recently infected plants, fruits might not be produced or, if produced, are small and unmarketable. In common bean, some TYLCVs produce the bean leaf crumple disease, with thickening, epinasty, crumpling, blade reduction and upward curling of leaves, as well as abnormal shoot proliferation and internode reduction; the very small leaves result in a bushy appearance.
Dual isotope and isotopomer measurements for the understanding of N2O production and consumption during denitrification in an arable soil
Authors: Meijide A. , Cardenas L. M. , Bol R. , Bergstermann A. , Goulding K. , Well R. , Vallejo A. , Scholefield D.
Published: March 2010

The aim of our research was to obtain information on the isotopic fingerprint of nitrous oxide (N2O) associated with its production and consumption during denitrification. An arable soil was preincubated at high moisture content and subsequently amended with glucose (400 kg C ha−1) and KNO3 (80 kg N ha−1) and kept at 85% water‐filled pore space. Twelve replicate samples of the soil were incubated for 13 days under a helium‐oxygen atmosphere, simultaneously measuring gas fluxes (N2O, N2 and CO2) and isotope signatures (δ18O‐N2O, δ15Nbulk‐N2O, δ15Nα, δ15Nβ and 15N site preference) of emitted N2O. The maximum N2O flux (6.9 ± 1.8 kg N ha−1 day−1) occurred 3 days after amendment application, followed by the maximum N2 flux on day 4 (6.6 ± 3.0 kg N ha−1 day−1). The δ15Nbulk was initially −34.4‰ and increased to +4.5‰ during the periods of maximum N2 flux, demonstrating fractionation during N2O reduction, and then decreased. The δ18O‐N2O also increased, peaking with the maximum N2 flux and remaining stable afterwards. The site preference (SP) decreased from the initial +7.5 to −2.1‰ when the N2O flux peaked, and then simultaneously increased with the appearance of the N2 peak to +8.6‰ and remained stable thereafter, even when the O2 supply was removed. We suggest that this results from a non‐homogenous distribution of NO in the soil, possibly linked to the KNO3 amendments to the soil, causing the creation of several NO pools, which affected differently the isotopic signature of N2O and the N2O and N2 fluxes during the various stages of the process. The N2O isotopologue values reflected the temporal patterns observed in N2O and N2 fluxes. A concurrent increase in 15N site preference and δ18O of N2O was found to be indicative of N2O reduction to N2.
Developmental variation in resistance and tolerance in a multi‐host–parasite system
Authors: Rohr Jason R. , Raffel Thomas R. , Hall Callyn A.
Published: March 2010

1. Organisms can protect themselves against parasitism by reducing either parasite burden (resistance) or damage caused by parasites at a given burden (tolerance), but little is known about resistance and tolerance to multiple parasites among wild animal populations and species. The fitness effects of parasitism can be broken down into two components: (i) cost of parasite exposure, the difference in fitness between organisms that were not exposed to parasites and those that were exposed but not infected, and (ii) tolerance, the change in host fitness as a function of parasite burden. For amphibians, a taxon that is being decimated by disease, knowing which species and ontogenetic stages are least resistant or least tolerant to which parasites would help target research and management efforts.

2. We reared American toad (Bufo americanus) and green frog (Rana clamitans) tadpoles in a common garden environment and quantified survival and trematode burdens after exposure to 20 Echinostoma trivolvis, Ribeiroia ondatrae or plagiorchid trematode cercariae.

3. All three trematodes caused significant B. americanus mortality, but R. ondatrae was the only species to induce significant mortality of R. clamitans and was the most deadly of the parasites. Young tadpoles had greater parasite‐induced mortality than older tadpoles.

4. Mortality patterns were driven by B. americanus having lower resistance and a higher cost of parasite exposure than R. clamitans, older tadpoles having higher tolerance than younger tadpoles, B. americanus and R. clamitans exhibiting lower resistance and a higher cost of parasite exposure, respectively, to R. ondatrae relative to the other tested trematodes, and skin‐penetrating trematodes inducing a higher cost of parasite exposure than non‐skin‐penetrators. Host size was not predictive of resistance but was a positive predictor of the cost of resistance and tolerance; however, size alone could not fully account for host differences in tolerance.

5. Interactions among developmental stage and host and trematode species emphasize the plasticity and context‐dependency of defence strategies and the importance of considering resistance and tolerance to multiple parasites in wild host species.
Phylogeographic analysis detects congruent biogeographic patterns between a woodland agamid and Australian wet tropics taxa despite disparate evolutionary trajectories
Authors: Edwards Danielle L. , Melville Jane
Published: March 2010

Aim  To test the congruence of phylogeographic patterns and processes between a woodland agamid lizard (Diporiphora australis) and well‐studied Australian wet tropics fauna. Specifically, to determine whether the biogeographic history of D. australis is more consistent with a history of vicariance, which is common in wet tropics fauna, or with a history of dispersal with expansion, which would be expected for species occupying woodland habitats that expanded with the increasingly drier conditions in eastern Australia during the Miocene–Pleistocene.

Location  North‐eastern Australia.

Methods  Field‐collected and museum tissue samples from across the entire distribution of D. australis were used to compile a comprehensive phylo‐geographic dataset based on c. 1400 bp of mitochondrial DNA (mtDNA), incorporating the ND2 protein‐coding gene. We used phylogenetic methods to assess biogeographic patterns within D. australis and relaxed molecular clock analyses were conducted to estimate divergence times. Hierarchical Shimodaira–Hasegawa tests were used to test alternative topologies representing vicariant, dispersal and mixed dispersal/vicariant biogeographic hypotheses. Phylogenetic analyses were combined with phylogeographic analyses to gain an insight into the evolutionary processes operating within D. australis.

Results  Phylogenetic analyses identified six major mtDNA clades within D. australis, with phylogeographic patterns closely matching those seen in many wet tropics taxa. Congruent phylogeographic breaks were observed across the Black Mountain Corridor, Burdekin and St Lawrence Gaps. Divergence amongst clades was found to decrease in a north–south direction, with a trend of increasing population expansion in the south.

Main conclusions  While phylogeographic patterns in D australis reflect those seen in many rain forest fauna of the wet tropics, the evolutionary processes underlying these patterns appear to be very different. Our results support a history of sequential colonization of D. australis from north to south across major biogeographic barriers from the late Miocene–Pleistocene. These patterns are most likely in response to expanding woodland habitats. Our results strengthen the data available for this iconic region in Australia by exploring the understudied woodland habitats. In addition, our study shows the importance of thorough investigations of not only the biogeographic patterns displayed by species but also the evolutionary processes underlying such patterns.
Birds and ants provide complementary seed dispersal in a neotropical savanna
Authors: Christianini Alexander V. , Oliveira Paulo S.
Published: March 2010

1. A substantial portion of the crop of fruiting trees falls beneath parent plants as a result of dispersal failure. Such diaspores are considered as waste because the likelihood of plant recruitment is usually very small close to parent trees. However, many animals may rescue fallen diaspores and provide them with another chance of dispersal and establishment.

2. We investigated the effectiveness of two broad types of seed dispersal vectors for the regeneration of Xylopia aromatica in the Brazilian cerrado savanna: birds that remove diaspores from plant canopies and ants that harvest diaspores on the ground under the parent plant (as rescuers) or from bird feces (as secondary dispersers).

3. Birds removed a mean of 32% of the crop from plant canopies, but removal was independent of crop size. A large part of the crop (mean of 25%) landed beneath parent plants or was dropped after manipulation by vertebrate frugivores as viable diaspores. Ants from at least five genera removed most fallen diaspores (up to 83%) within 24 h. Ants influenced the fate of a large amount of the crop, and for some trees ants removed as many diaspores as birds.

4. Large ants rescued some diaspores to distances beyond the parent plant crown, but birds may remove diaspores 40‐fold farther. However, seedlings of X. aromatica were only found close to nests of large ants, probably due to diaspore rescuing and/or directed secondary dispersal by certain ant groups following primary dispersal by birds. Although an unknown percentage of seeds was lost to granivorous ants, diaspore removal by ants potentially enhances the likelihood of plant recruitment due to distance‐related benefits and directed dispersal to ant nests, while birds play a premier role in long‐distance seed dispersal and metapopulation dynamics.

5. Synthesis. Birds and ants provide complementary seed dispersal at different spatial scales to X. aromatica. Since ants remove most fallen diaspores beneath parent plants, the use of diaspore removal rates from plant canopy as a surrogate of plant fitness may be misleading. By acting as secondary dispersers, ants may also provide a fine‐tuned dispersal following long‐distance dispersal by birds (i.e. diplochory).
Tree diversity promotes insect herbivory in subtropical forests of south‐east China
Authors: Schuldt Andreas , Baruffol Martin , Böhnke Martin , Bruelheide Helge , Härdtle Werner , Lang Anne C. , Nadrowski Karin , Von Oheimb Goddert , Voigt Winfried , Zhou Hongzhang , Assmann Thorsten
Published: March 2010

1. Insect herbivory can strongly affect ecosystem processes, and its relationship with plant diversity is a central topic in biodiversity–functioning research. However, very little is known about this relationship from complex ecosystems dominated by long‐lived individuals, such as forests, especially over gradients of high plant diversity.

2. We analysed insect herbivory on saplings of 10 tree and shrub species across 27 forest stands differing in age and tree species richness in an extraordinarily diverse subtropical forest ecosystem in China. We tested whether plant species richness significantly influences folivory in these highly diverse forests or whether other factors play a more important role at such high levels of phytodiversity.

3. Leaf damage was assessed on 58 297 leaves of 1284 saplings at the end of the rainy season in 2008, together with structural and abiotic stand characteristics.

4. Species‐specific mean damage of leaf area ranged from 3% to 16%. Herbivory increased with plant species richness even after accounting for potentially confounding effects of stand characteristics, of which stand age‐related aspects most clearly covaried with herbivory. Intraspecific density dependence or other abiotic factors did not significantly influence overall herbivory across forest stands.

5. Synthesis. The positive herbivory–plant diversity relationship indicates that effects related to hypotheses of resource concentration, according to which a reduction in damage by specialized herbivores might be expected as host plant concentration decreases with increasing plant diversity, do not seem to be major determinants for overall herbivory levels in our phytodiverse subtropical forest ecosystem. We discuss the potential role of host specificity of dominant herbivores, which are often expected to show a high degree of specialization in many (sub)tropical forests. In the forest system we studied, a much higher impact of polyphagous species than traditionally assumed might explain the observed patterns, as these species can profit from a broad dietary mix provided by high plant diversity. Further testing is needed to experimentally verify this assumption.
The population biology of the early spider orchid Ophrys sphegodes Mill. III. Demography over three decades
Authors: Hutchings Michael J.
Published: March 2010

1. Compared to animals, long‐term, large‐scale demographic studies based on plants are scarce. A 32‐year plant‐based demographic study of the rare early spider orchid Ophrys sphegodes is presented, covering periods of management by cattle grazing (1975–1979) and sheep grazing (1980–2006).

2. Annual recruitment exceeded mortality under sheep grazing, but numbers of emergent plants did not increase for many years. Eventually, following rapid population increase, numbers fluctuated strongly, with high recruitment in 1 year followed by heavy mortality the next.

3. The population’s distribution between different life states varied considerably, even between consecutive years with identical management. On average, almost 30% of plants were dormant. Most dormant periods lasted <4 years (c. 78% were ≤ 2 years), but dormancy of up to 8 years was recorded.

4. Most orchids had short lives from first to last appearance, but some lived for >20 years. Age‐specific survivorship data yielded a half‐life of 2.25 years.

5. Peak flowering date advanced by 0.5 day year−1 during the study. Flowering was earlier after warmer years and later after winters with more frosts. Inflorescence height and leaf number were positively correlated with rainfall during inflorescence extension, but negatively correlated with temperature and sunshine hours over up to a year before flowering. Higher temperature was associated with less of the population flowering and more being vegetative. The proportion in dormancy was unaffected by climatic variables.

6. Annual recruitment and mortality were positively correlated with temperature in the previous year, and annual recruitment was positively correlated with the number of flowering plants in each of the two previous years. In most years, <1 plant was recruited per flowering plant in each of the two previous years.

7. Despite a dramatic increase in the number of emergent plants c. 10 years after management changed to sheep grazing, and large numbers of emergent plants thereafter, mortality greatly exceeded recruitment over the last 10 years of this study.

8. Synthesis. Conservation of orchids like O. sphegodes, which have numerous ‘weedy’ life‐history characteristics, is heavily reliant on appropriate management. Although previous management prescriptions for conservation remain valid, some site disturbance will be beneficial to recruitment.
Characterization of susceptibility and carrier status of burbot, Lota lota (L.), to IHNV, IPNV, Flavobacterium psychrophilum, Aeromonas salmonicida and Renibacterium salmoninarum
Authors: Polinski M P , Fehringer T R , Johnson K A , Snekvik K R , LaPatra S E , LaFrentz B R , Ireland S C , Cain K D
Published: March 2010

In this study, susceptibility and potential carrier status of burbot, Lota lota, were assessed for five important fish pathogens. Burbot demonstrated susceptibility and elevated mortality following challenge with infectious haematopoietic necrosis virus (IHNV) by immersion and to Aeromonas salmonicida by intraperitoneal (i.p.) injection. IHNV persisted in fish for at least 28 days, whereas A. salmonicida was not re‐isolated beyond 17 days post‐challenge. In contrast, burbot appeared refractory to Flavobacterium psychrophilum following intramuscular (i.m.) injection and to infectious pancreatic necrosis virus (IPNV) by immersion. However, i.p injection of IPNV resulted in re‐isolation of virus from fish for the duration of the 28 day challenge. Renibacterium salmoninarum appeared to induce an asymptomatic carrier state in burbot following i.p. injection, but overt manifestation of disease was not apparent. Viable bacteria persisted in fish for at least 41 days, and bacterial DNA isolated by diagnostic polymerase chain reaction was detected from burbot kidney tissue 90 days after initial exposure. This study is the first to investigate susceptibility of burbot to selected fish pathogens, and this information will aid in efforts to culture and manage this species.
Controlled release recombinant human interferon‐α2b for treating patients with chronic hepatitis C genotype 1: a phase 2a clinical trial
Authors: Dzyublyk I. , Yegorova T. , Moroz L. , Popovych O. , Zaytsev I. , Miroshnichenko V. , Kromminga A. , Wilkes M. M. , van Hoogdalem E. J. , Humphries J. E.
Published: March 2010

Summary.  Better convenience and tolerability and sustained therapeutic concentrations might improve interferon (IFN) treatment for chronic hepatitis C virus (HCV) infection. In an open‐label, randomized study, controlled release free (chemically unmodified) recombinant human IFN‐α2b in poly(ether–ester) microspheres (CR‐rhIFN‐α2b), was injected at doses of 160, 320, 480 or 640 μg every 2 weeks for 12 weeks with concomitant weight‐based oral ribavirin in 32 treatment‐naïve patients with chronic HCV genotype 1. Treatment was well tolerated, with 31 patients (97%) successfully completing the study. Full doses of CR‐rhIFN‐α2b were administered on 96% of scheduled occasions. Flu‐like symptoms were generally mild and brief. Injection site reactions developed in 13 patients (41%), and neutropenia occurred in six of eight patients receiving 640 μg. In the 320, 480 and 640 μg groups, 62–75% of patients achieved a ≥2 log10 HCV RNA reduction by 4 weeks and 88–100% by 12 weeks. For those groups, the pooled median time to ≥2 log10 reduction was 11 days (95% confidence interval, 7–35 days). In those groups, viral reduction below the limit of detection was accomplished in 25% of patients by 4 weeks and in 62% by 12 weeks. The 160‐μg dose was less potent. After CR‐rhIFN‐α2b injection, stable plateau levels of serum IFN‐α2b were generally reached within 72 h. Treatment‐emergent neutralizing antibodies to IFN‐α2b were observed in one patient. No antibodies to host plant proteins were detected. CR‐rhIFN‐α2b with ribavirin cotherapy was well tolerated and displayed potent early antiviral activity in patients with chronic HCV genotype 1.
Clinical, epidemiological characteristics and indications for liver biopsy and treatment in immigrants with chronic hepatitis B at a referral hospital in Madrid
Authors: Pérez‐Molina J. A. , Herrero‐Martínez J. M. , Norman F. , Pérez‐Ayala A. , Monge‐Mahillo B. , Navarro‐Beltrá M. , López‐Vélez R.
Published: March 2010

Summary.  The increase in immigration from less developed countries to Europe has led to an increase in the incidence of hepatitis B infection. The objective of this study was to describe the clinical, epidemiological characteristics and indications for treatment of chronic hepatitis B in a cohort of immigrants, given the relative lack of current evidence. We performed a noninterventional retrospective chart review; different characteristics depending on geographical origin were compared. A case‐control study was also performed to describe factors potentially associated with chronic or past hepatitis B virus (HBV) infection. We selected a random sample of 436 patients out of the 2989 immigrants attending during the study period (1989‐2008). Hepatitis B serology was performed in 74% (322/436): 10.6% had chronic HBV infection (95% CI: 7.4–13.7%), and 46.9% had evidence of past infection (95% CI: 41.7–52.0%). The average age was 31 years, 60% were men, and 70% were sub‐Saharan Africans. Chronic infection was related to being men (OR 2.03; 95%CI: 1.29–3.18), younger (OR 0.98; 0.96–0.99) and sub‐Saharan African (OR 5.41; 2.71–10.83). Past or current infection was related to male sex (OR 2.80; 1.81–4.30), longer time elapsed until first seen at the unit (OR 0.998; 0.997–1.000), HIV infection (OR 4.99; 1.15–21.60) and being sub‐Saharan African (OR 15.46; 8.97–27.18). These associations were not confirmed after adjustment for geographical origin. In 27% and 29.5% of patients, liver biopsy and treatment, respectively, would have been indicated. Prevalence of chronic HBV infection amongst immigrants is high, especially in sub‐Saharan Africans. Almost a third could be considered for liver biopsy or antiviral therapy.
Single‐step real‐time PCR to quantify hepatitis B virus and distinguish genotype D from non‐D genotypes
Authors: Amini‐Bavil‐Olyaee S. , Pourkarim M. R. , Schaefer S. , Mahboudi F. , Van Ranst M. , Adeli A. , Trautwein C. , Tacke F.
Published: March 2010

Summary.  Hepatitis B virus (HBV) viral load and its genotype play important roles in clinical outcome, management of disease and response to antiviral therapy. In many parts of the world such as Europe or the Middle East, distinguishing HBV genotype D from non‐D is most relevant for treatment decisions, because genotype D‐infected patients respond poorly to interferon‐based therapeutic regimens. Here, we developed an in‐house real‐time PCR to concordantly assess HBV genotype (D vs non‐D) based on melt curve analysis and quantify the viral load. Genotype distinction was established with control plasmids of all HBV genotypes and validated with 57 clinical samples from patients infected with six different HBV genotypes. Our in‐house real‐time PCR assay could discriminate HBV genotype D from non‐D using single‐step melt curve analysis with a 2 °C difference in the melt curve temperature in all samples tested. Viral load quantification was calibrated with the WHO HBV international standard, demonstrating an excellent correlation with a commercial kit (r = 0.852; P < 0.0001) in a linear range from 3.2 × 102 to 3.2 × 1010 IU/mL. In conclusion, we developed a rapid, simple and cost‐effective method to simultaneously quantify and distinguish HBV genotypes D from non‐D with a single‐step PCR run and melt curve analysis. This assay should be a useful diagnostic alternative to aid clinical decisions about initiation and choice of antiviral therapy, especially in geographical regions with a high prevalence of HBV genotype D.
Open‐label, ascending dose, prospective cohort study evaluating the antiviral efficacy of Rosuvastatin therapy in serum and lipid fractions in patients with chronic hepatitis C
Authors: Patel K. , Jhaveri R. , George J. , Qiang G. , Kenedi C. , Brown K. , Cates C. , Zekry A. , Tillmann H. L. , Elliott L. , Kilaru R. , Albrecht J. , Conrad A. , G McHutchison J.
Published: March 2010

Summary.  HMG CoA reductase inhibition suppresses in vitro HCV replication through depletion of cellular sterol proteins such as geranylgeraniol. Our aims were to prospectively evaluate the changes in serum and lipid fraction HCV RNA with Rosuvastatin in non‐responder (NR) patients with CHC. A total of 11 patients with CHC genotype‐1 received Rosuvastatin at 20 mg qd (weeks 0–4), 40 mg qd (weeks 5–12), with 4 week follow up. Lipid fractions were separated by a sucrose density gradient ultracentrifugation, HCV RNA determined at wks 0, 2, 4, 8, 12, 16 in serum, and in selected very low‐ (VLDF) to high‐density (HDF) lipid fractions. A reduction in LDL and total cholesterol (TC) was not accompanied by significant decline in HCV RNA. At baseline, there was an inverse correlation between HDL and HCV RNA (ρ = −0.45, P = 0.036). At 20 mg, there was correlation between change (Δ) in TG and Δ HCV RNA (ρ = 0.75, P = 0.007), Δ ALT and Δ TC (ρ = −0.64, P = 0.03) and Δ LDL (ρ = −0.67, P = 0.02). At 40 mg, Δ TG maintained a positive correlation with Δ HCV RNA (ρ = 0.65, P = 0.03). There was a group difference for HCV RNA in relation to lipid fractions (P = 0.04) but not study time intervals (P = 0.17); mean log HCV RNA was greater in VLDF compared to HDF (5.81 ± 0.59 vs 5.06 ± 0.67, P = 0.0002) with no other differences to study time intervals (P = 0.099). Short‐term Rosuvastatin monotherapy is not associated with significant changes in serum or lipid fraction HCV RNA in NR patients. HCV co‐localizes with the lowest density lipid fractions in serum.
Light and nitrogen competition limitLolium perennein experimental grasslands of increasing plant diversity
Authors: Roscher C. , Kutsch W. L. , Schulze E.‐D.
Published: March 2010

Positive species richness effects on aboveground community productivity in experimental grasslands have been reported to correlate with variable responses of individual species. So far, it is largely unknown whether more complete use of resources at the community level correlates with resource limitation of particular species and may explain their decreasing performance with increasing plant diversity. Using the subordinate grass speciesLolium perenneL. as a model, we monitored populations in 82 experimental grasslands of different plant diversity (Jena Experiment) from year 2 to 6 after establishment, and measured ecophysiological leaf traits related to light and nutrient acquisition and use. Population and plant individual sizes ofL. perennedecreased with increasing species richness. A decrease in transmitted light with increasing species richness and legume proportion correlated with increasing specific leaf area (SLA). Despite this morphological adaptation to lower light availability, decreasing foliar δ13C signatures with increasing species richness and low variation in leaf gas exchange and chlorophyll concentrations suggested a low capacity ofL. perennefor adjustment to canopy shade. Leaf nitrogen concentrations and foliar δ15N signatures indicated a better N supply in communities with legumes and a shift in the uptake of different N forms with increasing species richness. Leaf blade nitrate and carbohydrate concentrations as indicators of plants nutritional status supported that light limitation with increasing species richness and legume proportions, combined with a N limitation in communities with increasing proportions of non‐legumes, correlated with the decreasing performance ofL. perennein communities of increasing plant diversity.
Shrinking genomes? Evidence from genome size variation inCrepis(Compositae)
Authors: Enke N. , Fuchs J. , Gemeinholzer B.
Published: March 2010

Large‐scale surveys of genome size evolution in angiosperms show that the ancestral genome was most likely small, with a tendency towards an increase in DNA content during evolution. Due to polyploidisation and self‐replicating DNA elements, angiosperm genomes were considered to have a ‘one‐way ticket to obesity’ (Bennetzen & Kellogg 1997). New findings on how organisms can lose DNA challenged the hypotheses of unidirectional evolution of genome size. The present study is based on the classical work of Babcock (1947a) on karyotype evolution withinCrepisand analyses karyotypic diversification within the genus in a phylogenetic context. Genome size of 21Crepisspecies was estimated using flow cytometry. Additional data of 17 further species were taken from the literature. Within 30 diploidCrepisspecies there is a striking trend towards genome contraction. The direction of genome size evolution was analysed by reconstructing ancestral character states on a molecular phylogeny based on ITS sequence data. DNA content is correlated to distributional aspects as well as life form. Genome size is significantly higher in perennials than in annuals. Within sampled species, very small genomes are only present in Mediterranean or European species, whereas their Central and East Asian relatives have larger 1C values.
The spectrum of clinical paediatric endocrinology: 28 years of referrals to an individual consultant
Authors: Thomsett Michael J
Published: March 2010

Aim:  To review referrals throughout the career of an individual paediatric endocrinologist.

Methods:  A retrospective cohort study in metropolitan clinics in Queensland analysed details of all 9062 patients aged <18 years referred between January 1980 and December 2007 to determine the proportion of diagnoses in major disease categories and changes in referral patterns over time.

Results:  Short stature (29%), type‐1 diabetes mellitus (20%) and pubertal disorders (12%) accounted for most cases, with thyroid disorders (7%), obesity (6%), tall stature (5%) and hypothalamic‐pituitary disorders (4%) the next commonest. An organic cause for short stature, early puberty, late puberty, tall stature and obesity was found in 39%, 32%, 19%, 15% and 6% of cases, respectively. Boys were more likely to present with short stature or delayed puberty, and girls with tall stature and early puberty. Substantially fewer boys than girls were diagnosed in infancy with congenital adrenal hyperplasia, suggesting that some may be dying undiagnosed. Comparisons between 1980 and 1984, and 2000–2004 revealed increases in the percentage of referrals for type‐1 diabetes mellitus (particularly in the young), early puberty, hypothalamic‐pituitary and bone disorders, and decreases in those for short and tall stature.

Conclusions:  Disorders of growth and puberty accounted for 52% of referrals and many have an organic cause. A neonatal screening programme for congenital adrenal hyperplasia is overdue. Changing attitudes to short and tall stature and a profound increase in new cases of diabetes mellitus indicate that substantially greater resources for treatment of childhood diabetes mellitus will be required in future.
Risk factors and clinical management of haemorrhage after open nephron‐sparing surgery
Authors: Huber Johannes , Pahernik Sascha , Hallscheidt Peter , Sommer Christof Matthias , Hatiboglu Gencay , Haferkamp Axel , Hohenfellner Markus
Published: March 2010

Study Type – Therapy (case series) Level of Evidence 4

OBJECTIVE

To identify risk factors for relevant haemorrhage after open nephron‐sparing surgery (NSS) for renal cell carcinoma, and to evaluate its clinical management.

PATIENTS AND METHODS

We evaluated bleeding complications after open NSS in 196 consecutive cases (193 patients) at our institution. The median (range) age of the patients was 64 (3–91) years and the tumour diameter was 2.7 (0.5–11.8) cm. Sex, age, body mass index, imperative vs elective indication, year of surgery, multifocality, tumour diameter and malignant vs benign pathology were tested exploratively and significant variables entered in a multivariate model. The clinical management of haemorrhage after NSS was analysed.

RESULTS

Bleeding required conservative (six), interventional (six) or surgical (three) therapy in 15 of the 196 cases (8%). Imperative indication (P= 0.043) and multifocality (P= 0.039) were independent risk factors in a multivariate model. Compared with superselective percutaneous transarterial embolization (TAE), surgery as a primary therapeutic option was more likely within 24 h after NSS (P= 0.012). Bleeding was finally controlled in all patients, while the kidney was preserved in 11 patients. There was only a minor decline of renal function at the 3‐month follow‐up.

CONCLUSIONS

We identified multifocal tumours and imperative indication as risk factors for haemorrhage after NSS. The management was very successful, relying on TAE as an effective and safe treatment for bleeding after NSS. In rare cases of severe bleeding surgical exploration is unavoidable, with a lower chance of kidney preservation.
Separation of Regulatory Powers When Contracts Are Incomplete
Authors: BARTOLINI DAVID
Published: March 2010

The investment of a regulated firm affects the service/good provided on many dimensions. Should an integrated regulator take care of them all? Or is it better to have separate regulators responsible for them? We analyze the effect of the separation of regulatory powers on the regulated firm's ex ante incentive to invest in a “cooperative” innovation. The effects of the innovation are not verifiable and the cost of investing is sunk, hence, there is a problem of hold‐up. We find that when the innovation produces opposite effects the ex ante firm's incentive to invest is larger in the case of separation than in the case of integrated regulation. We also stress the risk of over‐investment that the separation of regulatory powers may induce. We maintain that along with classical incentive regulation—which mainly provides incentives for the firm to be efficient—the separation of regulatory powers may play a role in providing an incentive for cooperative innovations.
Strategic Consumption Complementarities: Can Price Flexibility Eliminate Inefficiencies and Instability?
Authors: RANDON EMANUELA , SIMMONS PETER
Published: March 2010

Generally, two facts occur with strategic complementarities and fixed prices: (i) the equilibria are multiple and (ii) if the complementarities are strong, the law of demand is violated and the equilibrium is unstable. In this paper, we analyse the effect of price flexibility on these features as well as on market welfare properties. Assuming an exchange economy with H agents consuming two goods with one strategic complement, we show that flexibility of prices may remove both the multiplicity of the equilibria and the instability of behavior when the externalities are strong. Moreover, we find conditions to correct instability when it is caused by perverse wealth effects. When preferences are quasilinear and identical, if the externality is beneficial, any equilibrium is Pareto optimal despite the externality. But if the externality is detrimental, corrections are required.
The Social Value of Cost Information in a Monopolistically Competitive Economy
Authors: SZCZUTKOWSKI ANDREAS
Published: March 2010

An economy with monopolistic competition is endowed with an information system that produces a public information signal correlated to uncertain costs of production. Investment in the monopolistic competition sector is determined by consumers' savings under uncertainty. Savings are always lower than their efficient levels in the presented economy. If consumers' preferences exhibit prudence, then an improvement of the underlying information system (in the sense ofBlackwell 1953) leads to a decrease of expected savings. The social value of information may be negative in that case from an ex ante point of view. Better information may strengthen the market failure caused by imperfect competition. Without precautionary saving (negative prudence), the social value of information is always positive.
Effects of the cell type‐specific ablation of the cAMP‐responsive transcription factor in noradrenergic neurons on locus coeruleus firing and withdrawal behavior after chronic exposure to morphine
Authors: Parlato Rosanna , Cruz Hans , Otto Christiane , Murtra Patricia , Parkitna Jan Rodriguez , Martin Miquel , Bura Simona A. , Begus‐Nahrmann Yvonne , Von Bohlen und Halbach Oliver , Maldonado Rafael , Schütz Günther , Lüscher Christian
Published: March 2010

J. Neurochem.(2010)115, 563–573.

Repeated exposure to opiates leads to cellular and molecular changes and behavioral alterations reflecting a state of dependence. In noradrenergic neurons, cyclic AMP (cAMP)‐dependent pathways are activated during opiate withdrawal, but their contribution to the activity of locus coeruleus noradrenergic neurons and behavioral manifestations remains controversial. Here, we test whether the cAMP‐dependent transcription factors cAMP responsive element binding protein (CREB) and cAMP‐responsive element modulator (CREM) in noradrenergic neurons control the cellular markers and the physical signs of morphine withdrawal in mice. Using the Cre/loxP system we ablated theCreb1gene in noradrenergic neurons. To avoid adaptive effects because of compensatory up‐regulation of CREM, we crossed the conditionalCreb1mutant mice with aCrem−/− line. We found that the enhanced expression of tyrosine hydroxylase normally observed during withdrawal was attenuated in CREB/CREM mutants. Moreover, the withdrawal‐associated cellular hyperactivity andc‐fosexpression was blunted. In contrast, naloxone‐precipitated withdrawal signs, such as jumping, paw tremor, tremor and mastication were preserved. We conclude by a specific genetic approach that the withdrawal‐associated hyperexcitability of noradrenergic neurons depends on CREB/CREM activity in these neurons, but does not mediate several behavioral signs of morphine withdrawal.
Regulation of adult neural progenitor cells by Galectin‐1/β1 Integrin interaction
Authors: Sakaguchi Masanori , Imaizumi Yoichi , Shingo Tetsuro , Tada Hirobumi , Hayama Ko , Yamada Osamu , Morishita Tsuyoshi , Kadoya Toshihiko , Uchiyama Noboru , Shimazaki Takuya , Kuno Atsushi , Poirier Françoise , Hirabayashi Jun , Sawamoto Kazunobu , Okano Hideyuki
Published: March 2010

J. Neurochem. (2010) 113, 1516–1524.

Neural stem cells (NSCs) proliferate and generate new neurons in the adult brain. A carbohydrate‐binding protein (lectin), Galectin‐1, is expressed in the NSCs in the subependymal zone (SEZ) of the adult mouse brain. The infusion and knockout of Galectin‐1 in the SEZ results in an increase and decrease, respectively, of NSCs and subsequently born progenitor cells. The molecular mechanism of this effect, however, has been unknown. Previous studies outside the brain suggest that Galectin‐1 binds to a carbohydrate structure of β1 Integrin and modulates cell adhesion. Here, we studied the functional interaction between Galectin‐1 and β1 Integrin in the adult mouse SEZ. β1 Integrin was purified from adult SEZ tissue by binding to a Galectin‐1 affinity column, and this binding depended on Galectin‐1’s carbohydrate‐binding activity. In adult brain sections, Galectin‐1‐binding activity was detected on β1 Integrin‐expressing cells in the SEZ. Furthermore, in the adult SEZ, the simultaneous infusion of a β1 Integrin‐neutralizing antibody with Galectin‐1 protein reversed the increasing effect of Galectin‐1 on the number of adult neural progenitor cells (NPCs). Finally, intact β1 Integrin was required for Galectin‐1’s function in NPC adhesion in vitro. These results suggest that the interaction between β1 Integrin and Galectin‐1 plays an important role in regulating the number of adult NPCs through mechanisms including cell adhesion.
Neurochemical properties of enkephalinergic neurons in lumbar spinal dorsal horn revealed by preproenkephalin–green fluorescent protein transgenic mice
Authors: Huang Jing , Chen Jing , Wang Wei , Wang Wen , Koshimizu Yoshinori , Wei Yan‐Yan , Kaneko Takeshi , Li Yun‐Qing , Wu Sheng‐Xi
Published: March 2010

J. Neurochem. (2010) 113, 1555–1564.

Enkephalin (ENK) has been implicated in nociceptive transmission in the spinal cord while its functional role is not clear because of difficulties in ideally visualizing ENKergic neurons. We thus developed preproenkephalin–green fluorescent protein transgenic mice to better identify ENKergic neurons. Real‐time reverse transcriptase‐polymerase chain reaction (RT‐PCR) together with immunohistochemistry and in situ hybridization were first employed to confirm the successful transgenic manipulation and its application in showing spinal ENKergic neurons. The proportions of ENKergic neurons in the spinal cord laminae I, II, III and IV–VI among dorsal horn neurons were 15.8 ± 3.1%, 39.5 ± 3.3%, 11.8 ± 1.9% and 10.7 ± 2.1%, respectively. Double labeling with other molecules was then performed to further clarify the neurochemical properties of spinal ENKergic neurons. GABA was found to exist in 42.9 ± 2.8% of ENKergic neurons that were mainly located in lamina I–III. The proportions of parvalbumin‐, calretinin‐, calbindin‐ and neuronal nitric oxide synthase‐positive cells among the ENKergic neurons were 5.2 ± 0.7%, 42.6 ± 2.3%, 25.8 ± 2.2% and 11.1 ± 1.6%, respectively. Compared with previously findings obtained with ENK antibody labeling, this line of newly generated mice can be a reliable tool for the study of specific spinal ENKergic neuronal population.
A central role for RhoA during oligodendroglial maturation in the switch from Netrin‐1‐mediated chemorepulsion to process elaboration
Authors: Rajasekharan Sathyanath , Bin Jenea M. , Antel Jack P. , Kennedy Timothy E.
Published: March 2010

J. Neurochem. (2010) 113, 1589–1597.

The guidance cue netrin‐1 and its receptor Deleted in Colorectal Cancer play distinct roles during different stages of oligodendrocyte development. A gradient of netrin‐1 repels migrating oligodendrocyte precursor cells (OPCs) in the embryonic spinal cord by promoting process collapse, but later in development netrin‐1 increases oligodendrocyte process extension and branching. Here we investigate the intracellular mechanism that governs this switch in response to netrin‐1, and focus on the role of the GTPase RhoA and its effector Rho Kinase (ROCK) downstream of netrin‐1 in OPCs and maturing oligodendrocytes. In OPCs, we show that netrin‐1 induces a sustained increase in RhoA activity that requires Deleted in Colorectal Cancer function. Furthermore, we demonstrate that activation of RhoA and ROCK is required for the reduction in OPC process length triggered by netrin‐1, and for the chemorepellent response made by OPCs to netrin‐1. Unlike OPCs, application of netrin‐1 to oligodendrocytes decreases RhoA activity. We demonstrate that inactivation of RhoA is essential for netrin‐1 to increase oligodendrocyte process branching. We conclude that netrin‐1 induces distinct morphological responses in OPCs and oligodendrocytes through differential regulation of RhoA activity.
Evaluating Non‐Uniform Residual Stress by the Hole‐Drilling Method With Concentric and Eccentric Holes. Part II: Application of the Influence Functions to the Inverse Problem
Authors: Beghini M. , Bertini L. , Mori L. F.
Published: March 2010

Abstract:  This part deals with the applications of the influence functions developed in part I to solve the inverse problem of determining residual stresses from the measured relaxed strains. The effects of the hole eccentricity and the number of strain gauges on the accuracy of the reconstructed residual stresses are considered for typical experimental conditions. Influence functions for eccentric holes reduce the error in the reconstructed residual stress for typical experimental conditions below 1%, instead of 10% which would be obtained neglecting the eccentricity. The analysis was also applied for comparing the performance of three‐ and six‐element rosettes for compensating eccentricities. When the eccentricity is not included in the elaboration, six‐element rosettes with couples of opposite strain gauges halve the error committed by using the equivalent three‐element rosette. However, if the eccentricity is included in the influence functions, the three element rosette can predict with a smaller error.
INTERPRETING THE SOCIAL MEANING OF DIFFERENT SHAPES OF HOUSE STRUCTURES BY EXAMINING THE FLOW OF RESOURCES: A CASE STUDY OF SAQACENGALJ AT THE SOUTHERN TIP OF TAIWAN
Authors: CHEN MAA‐LING , CHEN YI‐LIN , LEE HAI‐LING
Published: March 2010

Social differentiation is characterized by differences in social status and wealth, which are established and maintained by controlling and constraining the labour and flow of resources. This would affect the development of various aspects of a settlement in establishing hierarchical relationships. This study focuses on identifying the variations in the distribution of certain resources, such as imported goods, that help interpret the social meaning, particularly with regard to social status and wealth, of house structures having different shapes in an ethnic settlement in Taiwan. A petrographic study and residue analysis of the pottery along with spatial examination of the material remains were conducted to achieve the goal.
THE WRONGS AND RIGHTS OF UNIT VALUE INDICES
Authors: Silver Mick
Published: March 2010

There are two sides to unit value indices. The first is their widespread and unwarranted use based on customs data as surrogates for price relatives of product groups of exports and imports. For the aggregation of heterogeneous items, superlative price indices are best and unit value indices are biased. The second is the widespread and unwarranted use of price indices for homogeneous items, for which unit value indices are best and superlative price indices are biased. Then there is the “in‐between”: the case of broadly comparable items. This paper examines such issues.
Survivor Derivatives: A Consistent Pricing Framework
Authors: Dawson Paul , Dowd Kevin , Cairns Andrew J. G. , Blake David
Published: March 2010

Abstract

Survivorship risk is a significant factor in the provision of retirement income. Survivor derivatives are in their early stages and offer potentially significant welfare benefits to society. This article applies the approach developed by Dowd et al. (2006), Olivier and Jeffery (2004), Smith (2005), and Cairns (2007) to derive a consistent framework for pricing a wide range of linear survivor derivatives, such as forwards, basis swaps, forward swaps, and futures. It then shows how a recent option pricing model set out by Dawson et al. (2009) can be used to price nonlinear survivor derivatives, such as survivor swaptions, caps, floors, and combined option products. It concludes by considering applications of these products to a pension fund that wishes to hedge its survivorship risks.