bluuebunny/crossref_metadata_2025 huggingface dataset:
Fine mapping of the chicken salmonellosis resistance locus (SAL1)
Authors: Fife M. S. , Salmon N. , Hocking P. M. , Kaiser P.
Published: June 2009

Salmonella enterica serovar Typhimurium is a Gram‐negative bacterium that has a significant impact on both human and animal health. It is one of the most common food‐borne pathogens responsible for a self‐limiting gastroenteritis in humans and a similar disease in pigs, cattle and chickens. In contrast, intravenous challenge with S. Typhimurium provides a valuable model for systemic infection, often causing a typhoid‐like infection, with bacterial replication resulting in the destruction of the spleen and liver of infected animals. Resistance to systemic salmonellosis in chickens is partly genetically determined, with bacterial numbers at systemic sites in resistant lines being up to 1000‐fold fewer than in susceptible lines. Identification of genes contributing to disease resistance will enable genetic selection of resistant lines that will reduce Salmonella levels in poultry flocks. We previously identified a novel resistance locus on Chromosome 5, designated SAL1. Through the availability of high‐density SNP panels in the chicken, combined with advanced back‐crossing of the resistant and susceptible lines, we sought to refine the SAL1 locus and identify potential positional candidate genes. Using a 6th generation backcross mapping population, we have confirmed and refined the SAL1 locus as lying between 54.0 and 54.8 Mb on the long arm of Chromosome 5 (F = 8.72, P = 0.00475). This region spans 14 genes, including two very striking functional candidates; CD27‐binding protein (Siva) and the RAC‐alpha serine/threonine protein kinase homolog, AKT1 (protein kinase B, PKB).
The structural evolution of the Halten Terrace, offshore Mid‐Norway: extensional fault growth and strain localisation in a multi‐layer brittle–ductile system
Authors: Marsh N. , Imber J. , Holdsworth R. E. , Brockbank P. , Ringrose P.
Published: June 2009

Tectonic subsidence in rift basins is often characterised by an initial period of slow subsidence (‘rift initiation’) followed by a period of more rapid subsidence (‘rift climax’). Previous work shows that the transition from rift initiation to rift climax can be explained by interactions between the stress fields of growing faults. Despite the prevalence of evaporites throughout the geological record, and the likelihood that the presence of a regionally extensive evaporite layer will introduce an important, sub‐horizontal rheological heterogeneity into the upper crust, there have been few studies that document the impact of salt on the localisation of extensional strain in rift basins. Here, we use well‐calibrated three‐dimensional seismic reflection data to constrain the distribution and timing of fault activity during Early Jurassic–Earliest Cretaceous rifting in the Åsgard area, Halten Terrace, offshore Mid‐Norway. Permo‐Triassic basement rocks are overlain by a thick sequence of interbedded halite, anhydrite and mudstone. Our results show that rift initiation during the Early Jurassic was characterised by distributed deformation along blind faults within the basement, and by localised deformation along the major Smørbukk and Trestakk faults within the cover. Rift climax and the end of rifting showed continued deformation along the Smørbukk and Trestakk faults, together with initiation of new extensional faults oblique to the main basement trends. We propose that these new faults developed in response to salt movement and/or gravity sliding on the evaporite layer above the tilted basement fault blocks. Rapid strain localisation within the post‐salt cover sequence at the onset of rifting is consistent with previous experimental studies that show strain localisation is favoured by the presence of a weak viscous substrate beneath a brittle overburden.
High‐sensitive radioimmunoassay for human serum hepcidin
Authors: Grebenchtchikov Nicolai , Geurts‐Moespot Anneke J. , Kroot Joyce J. C. , Den Heijer Martin , Tjalsma Harold , Swinkels Dorine W. , Sweep Fred G. J.
Published: June 2009

The hepatic peptide hormone hepcidin plays a central role in body iron metabolism. Despite its promise as a biomarker, the availability of high‐sensitive hepcidin assays is still limited. We developed and validated a RadioImmunoAssay (RIA) to measure hepcidin quantitatively in human serum. This assay exhibited a very low detection limit (0·02 μg/l), low imprecision (coefficient of variation‐range 4·4–6·2%) and good linearity and recovery (range: 81–105%). Hepcidin levels of samples of controls and patients with iron deficiency and inflammation showed an excellent correlation with our previously described quantitative time‐of‐flight mass spectrometry assay (range 2·5–266·8 μg/l, r = 0·92, P < 0·0001). The RIA detected: (i) differences in mean hepcidin levels between men (n = 29) and women (n = 35), (ii) differences between individuals of different HFE‐genotypes (n = 60) and (iii) daily increases in hepcidin levels (n = 64). The assay (i) is easy to perform and many samples can be processed within one assay‐run, (ii) shows accurate, reproducible and high‐sensitive measurements and (iii) is anticipated to be particularly useful to study the effects of pathological and physiological stimuli on hepcidin levels in the lower range.
Post‐ingestive effects of nectar alkaloids depend on dominance status of bumblebees
Authors: MANSON JESSAMYN S. , THOMSON JAMES D.
Published: June 2009

Abstract 1. Secondary metabolites have acute or chronic post‐ingestive effects on animals, ranging from death to growth inhibition to reduced nutrient assimilation.

2. Although characterised as toxic, the nectar of Gelsemium sempervirens is not lethal to pollinators, even when the concentration of the nectar alkaloid gelsemine is very high. However, little is known about the sublethal costs of nectar alkaloids.

3. Using a microcolony assay and paired worker bumblebees, the present study measured the effects of artificial nectar containing gelsemine on oocyte development. Oocytes are a sensitive indicator of protein utilisation and general metabolic processes. We also calculated carbohydrate concentrations in the haemolymph to examine energetic costs of gelsemine consumption.

4. High concentrations of gelsemine significantly reduced mean oocyte width in subordinate bees, while dominant bees showed only a trend towards oocyte inhibition. Gelsemine consumption did not reduce carbohydrate concentrations in haemolymph.

5. The cost of ingesting gelsemine may be due to direct toxicity of alkaloids or may be an expense associated with detoxifying gelsemine. Detoxification of alkaloids can require reallocation of resources away from essential metabolic functions like reproduction. The risks associated with nectar alkaloid consumption are tied to both the social and nutritional status of the bee.
Pulmonary involvement of autoimmune pancreatitis
Authors: Tsushima K. , Tanabe T. , Yamamoto H. , Koizumi T. , Kawa S. , Hamano H. , Honda T. , Uehara T. , Kawakami S. , Kubo K.
Published: June 2009

Background  A wide variety of systemic lesions have been seen in patients with autoimmune pancreatitis. The pulmonary involvement of autoimmune pancreatitis was analysed to clarify the clinicopathological features of pulmonary lesions in comparison with pulmonary sarcoidosis.

Materials and methods  Nineteen patients had autoimmune pancreatitis and eight had pulmonary sarcoidosis. The symptoms, laboratory data, chest computed tomography, Gallium‐67 scintigraphy, pulmonary function testing and bronchoscopy findings, including the histological IgG4‐immunostaining and IgG subclasses in the bronchoalveolar lavage in autoimmune pancreatitis, were collected to compare them with pulmonary sarcoidosis.

Results  The serum total protein, IgG and IgG4 levels were found to be significantly elevated in comparison with pulmonary sarcoidosis. In autoimmune pancreatitis, 17 patients showed bilateral hilar lymphadenopathy, while eight showed pulmonary nodules on chest computed tomography. Eighteen of 19 patients on Gallium‐67 scintigraphy showed accumulation spots in either the hilar or mediastinal lymph nodes. Six patients with pulmonary nodules demonstrated accumulation spots in the corresponding lesions on chest computed tomography. All eight patients with pulmonary sarcoidosis showed accumulation spots in either the hilar or mediastinal lymph nodes. Bronchoalveolar lavage IgG4 in autoimmune pancreatitis showed a significant increase in comparison with pulmonary sarcoidosis. The histological findings obtained by a transbronchial lung biopsy showed the infiltration of lymphocytes and plasma cells in the thickened interstitum and alveoli with IgG4‐positive plasma cell infiltration in patients with autoimmune pancreatitis.

Conclusion  IgG4 in the bronchoalveolar lavage was seen at remarkably increased levels and IgG4‐positive plasma cells were identified in the pulmonary lesions of patients with autoimmune pancreatitis.
N‐acetylcysteine versus N‐acetylcysteine + theophylline for the prevention of contrast nephropathy
Authors: Baskurt M. , Okcun B. , Abaci O. , Dogan G. M. , Kilickesmez K. , Ozkan A. A. , Ersanli M. , Gurmen T.
Published: June 2009

Background  The use of N‐acetylcysteine or theophylline in specific subgroups of patients has been suggested to reduce the incidence of contrast‐induced nephropathy (CIN) in patients undergoing angiographic procedures. Our purpose was to compare the use of N‐acetylcysteine versus N‐acetylcysteine + theophylline for the prevention of CIN.

Materials and methods  We randomized 217 patients with estimated glomerular filtration rate (eGFR) (calculated by Modification of Diet in Renal Disease formula) between 30 and 60 mL min−1 1·73 m−2 who were undergoing coronary angiography to three prophylactic treatment groups:

Group 1: Intravenous hydration with isotonic saline (1 mL kg−1 h−1 for 12 h before and after contrast, n = 72).

Group 2: Intravenous hydration with isotonic saline (1 mL kg−1 h−1 for 12 h before and after contrast)+ N‐acetylcysteine (600 mg p.o. twice daily the preceding day and the day of angiography, n = 73).

Group 3: Intravenous hydration with isotonic saline (1 mL kg−1 h−1 for 12 h before and after contrast)+ N‐acetylcysteine + theophylline (600 mg N‐acetylcysteine p.o. and 200 mg theophylline p.o. twice daily for the preceding day and the day of angiography, n = 72).

The incidence of CIN (0·5 mg dL−1 increase in serum creatinine from the baseline value 48 h after intravascular injection of contrast) was compared in three groups.

Results  Of the 217 patients, 12 patients (5·5%) experienced CIN. Five patients (6·9%) in group 1, seven patients (9·6%) in group 2 and zero (0%) patients in group 3 experienced CIN (P < 0·033).

Conclusion  Among patients with eGFR between 30 and 60 mL min−1 1·73 m−2 undergoing coronary angiography, oral administration of N‐acetylcysteine + theophylline in addition to saline hydration has a beneficial effect in the prevention of CIN.
Daily energy expenditure increases in response to low nutritional stress in an Arctic‐breeding seabird with no effect on mortality
Authors: Welcker Jorg , Harding Ann M. A. , Kitaysky Alexander S. , Speakman John R. , Gabrielsen Geir W.
Published: June 2009

1. The regulation of energy expenditure in relation to food availability and its consequences for individual fitness in free‐ranging animals are poorly understood. Increased daily energy expenditure (DEE) may be viewed as the result of two different processes: expenditure may be forced upwards by low food availability (forcing hypothesis) or enabled to increase by high levels of food resources (enabling hypothesis). Several studies have suggested long‐term fitness costs due to increased mortality as a trade‐off to increased DEE.

2. We examined the relationship between energy expenditure and an indirect measure of food availability, and the short‐term fitness consequences associated with changes in DEE in a small, Arctic seabird, the little auk (Alle alle). We measured DEE of 43 parent little auks by the doubly labelled water method during two consecutive breeding seasons and inferred food availability from plasma concentrations of the stress hormone corticosterone (CORT).

3. We found that DEE was elevated by 26·7% in the year with reduced levels of CORT, indicating that little auks responded to increased food availability by increasing their DEE. These results support the enabling hypothesis. Elevated DEE was presumably caused by increased parental effort as reflected by higher chick provisioning rates and larger chick meals, and was associated with fitness benefits in terms of enhanced current reproductive success.

4. Contrary to earlier studies, our data did not indicate adverse effects associated with elevated DEE; there was no negative relationship between DEE and the probability of adults returning to the colony the following year. Instead, adult return rate was positively related to body mass, with lower return rates when food was limited.

5. These results suggest that ecological consequences associated with limited resource availability may outweigh possible direct negative physiological effects of elevated DEE.
Phylogenetic relationships, diversification and biogeography in Neotropical Brotogeris parakeets
Authors: Ribas Camila C. , Miyaki Cristina Y. , Cracraft Joel
Published: June 2009

Aim  We present a molecular phylogenetic analysis of Brotogeris (Psittacidae) using several distinct and complementary approaches: we test the monophyly of the genus, delineate the basal taxa within it, uncover their phylogenetic relationships, and finally, based on these results, we perform temporal and spatial comparative analyses to help elucidate the historical biogeography of the Neotropical region.

Location  Neotropical lowlands, including dry and humid forests.

Methods  Phylogenetic relationships within Brotogeris were investigated using the complete sequences of the mitochondrial genes cyt b and ND2, and partial sequences of the nuclear intron 7 of the gene for Beta Fibrinogen for all eight species and 12 of the 17 taxa recognized within the genus (total of 63 individuals). In order to delinetae the basal taxa within the genus we used both molecular and plumage variation, the latter being based on the examination of 597 skin specimens. Dates of divergence and confidence intervals were estimated using penalized likelihood. Spatial and temporal comparative analyses were performed including several closely related parrot genera.

Results  Brotogeris was found to be a monophyletic genus, sister to Myiopsitta. The phylogenetic analyses recovered eight well‐supported clades representing the recognized biological species. Although some described subspecies are diagnosably distinct based on morphology, there was generally little intraspecific mtDNA variation. The Amazonian species had different phylogenetic affinities and did not group in a monophyletic clade. Brotogeris diversification took place during the last 6 Myr, the same time‐frame as previously found for Pionus and Pyrilia.

Main conclusions  The biogeographical history of Brotogeris implies a dynamic history for South American biomes since the Pliocene. It corroborates the idea that the geological evolution of Amazonia has been important in shaping its biodiversity, argues against the idea that the region has been environmentally stable during the Quaternary, and suggests dynamic interactions between wet and dry forest habitats in South America, with representatives of the Amazonian biota having several independent close relationships with taxa endemic to other biomes.
Biogeography of Iberian freshwater fishes revisited: the roles of historical versus contemporary constraints
Authors: Filipe Ana F. , Araújo Miguel B. , Doadrio Ignacio , Angermeier Paul L. , Collares‐Pereira Maria J.
Published: June 2009

Aim  The question of how much of the shared geographical distribution of biota is due to environmental vs. historical constraints remains unanswered. The aim of this paper is to disentangle the contribution of historical vs. contemporary factors to the distribution of freshwater fish species. In addition, it illustrates how quantifying the contribution of each type of factor improves the classification of biogeographical provinces.

Location  Iberian Peninsula, south‐western Europe (c. 581,000 km2).

Methods  We used the most comprehensive data on native fish distributions for the Iberian Peninsula, compiled from Portuguese and Spanish sources on a 20‐km grid‐cell resolution. Overall, 58 species were analysed after being categorized into three groups according to their ability to disperse through saltwater: (1) species strictly intolerant of saltwater (primary species); (2) species partially tolerant of saltwater, making limited incursions into saltwaters (secondary species); and (3) saltwater‐tolerant species that migrate back and forth from sea to freshwaters or have invaded freshwaters recently (peripheral species). Distance‐based multivariate analyses were used to test the role of historical (basin formation) vs. contemporary environmental (climate) conditions in explaining current patterns of native fish assemblage composition. Cluster analyses were performed to explore species co‐occurrence patterns and redefine biogeographical provinces based on the distributions of fishes.

Results  River basin boundaries were better at segregating species composition for all species groups than contemporary climate variables. This historical signal was especially evident for primary and secondary freshwater fishes. Eleven biogeographical provinces were delineated. Basins flowing to the Atlantic Ocean north of the Tagus Basin and those flowing to the Mediterranean Sea north of the Mijares Basin were the most dissimilar group. Primary and secondary freshwater species had higher province fidelity than peripheral species.

Main conclusions  The results support the hypothesis that historical factors exert greater constraints on native freshwater fish assemblages in the Iberian Peninsula than do current environmental factors. After examining patterns of assemblage variation across space, as evidenced by the biogeographical provinces, we discuss the likely dispersal and speciation events that underlie these patterns.
The effect of hyperoxygenation and reduced flow in fresh water and subsequent infectious pancreatic necrosis virus challenge in sea water, on the intestinal barrier integrity in Atlantic salmon, Salmo salar L.
Authors: Sundh H , Olsen R‐E , Fridell F , Gadan K , Evensen Ø , Glette J. , Taranger G‐L , Myklebust R , Sundell K
Published: June 2009

In high intensive fish production systems, hyperoxygenation and reduced flow are often used to save water and increase the holding capacity. This commonly used husbandry practice has been shown to be stressful to fish and increase mortality after infectious pancreatic necrosis virus (IPNV) challenge, but the cause and effect relationship is not known. Salmonids are particularly sensitive to stress during smoltification and the first weeks after seawater (SW) transfer. This work aimed at investigating the impact of hyperoxygenation combined with reduced flow in fresh water (FW), on the intestinal barrier in FW as well as during later life stages in SW. It further aims at investigating the role of the intestinal barrier during IPNV challenge and possible secondary infections. Hyperoxygenation in FW acted as a stressor as shown by significantly elevated plasma cortisol levels. This stressful husbandry condition tended to increase paracellular permeability (Papp) as well as translocation of Aeromonas salmonicida in the posterior intestine of Atlantic salmon. After transfer to SW and subsequent IPNV challenge, intestinal permeability, as shown by Papp, and translocation rate of A. salmonicida increased in the anterior intestine, concomitant with further elevation in plasma cortisol levels. In the anterior intestine, four of five fish displayed alterations in intestinal appearance. In two of five fish, IPNV caused massive necrosis with significant loss of cell material and in a further two fish, IPNV caused increased infiltration of lymphocytes into the epithelium and granulocytes in the lamina propria. Hyperoxygenation and reduced flow in the FW stage may serve as stressors with impact mainly during later stages of development. Fish with an early history of hyperoxygenation showed a higher stress response concomitant with a disturbed intestinal barrier function, which may be a cause for the increased susceptibility to IPNV infection and increased susceptibility to secondary infections.
Development and evaluation of a loop‐mediated isothermal amplification assay for rapid and simple detection of Flavobacterium psychrophilum
Authors: Fujiwara‐Nagata E , Eguchi M
Published: June 2009

Flavobacterium psychrophilum is the causative agent of bacterial cold‐water disease and rainbow trout fry syndrome of salmonids. The pathogen has been reported from all regions in the world involved in salmonid aquaculture, but also from natural fresh‐water environments. We established a quantitative loop‐mediated isothermal amplification of DNA (LAMP) method to estimate quantities of F. psychrophilum. LAMP primers were designed based on the sequence of the DNA topoisomerase IV subunit B gene, parE, of F. psychrophilum. parE LAMP exhibited a high specificity for the parE gene of F. psychrophilum but not for other related species. parE LAMP detected the gene in a wide range of concentrations from 2.0 × 101 to 2.0 × 109 copies/reaction within 70 min and revealed a good correlation between threshold times and gene copy number.
NOD2/CARD15 genotype and common gastrointestinal diseases in 43 600 individuals
Authors: Yazdanyar S. , Nordestgaard B. G.
Published: June 2009

Abstract.  Yazdanyar S, Nordestgaard BG (Herlev Hospital, Herlev; Copenhagen University Hospital, University of Copenhagen, Copenhagen; Denmark). NOD2/CARD15 genotype and common gastrointestinal diseases in 43 600 individuals. J Intern Med 2010; 267 228–236.

Objectives.  NOD2/CARD15 is involved in the innate immune response and three polymorphisms in this gene (Arg702Trp rs2066844, Gly908Arg rs2066845 and Leu1007fsinsC rs5743293) have been associated with risk of the rare Crohn’s disease. We tested the hypothesis that polymorphisms in NOD2/CARD15 associate with risk of nine common gastrointestinal diseases.

Design and setting.  We genotyped 43 596 white individuals from the Danish general population followed for 31 years, during which time 782 developed oesophagitis and reflux, 1395 ulcus ventriculi and duodeni, 1384 gastritis and dyspepsia, 1407 appendicitis, 646 irritable bowel syndrome, 1301 infectious diseases of the gastrointestinal tract, 681 anal fissure, fistula and abscess, 826 gastrointestinal cancer and 161 developed cancer in liver and pancreas.

Results.  Some 89% were non‐carriers, 11% heterozygotes, 0.15% homozygotes and 0.23% compound heterozygotes. Cumulative incidences differed by genotype for appendicitis (log‐rank P = 0.02), anal fissure, fistula and abscess (P = 0.003) and gastrointestinal cancer (P = 0.004), but not for any of the other endpoints. Compared with non‐carriers, age and sex adjusted hazard ratios were 2.7 (95%CI 1.4–5.5) for appendicitis amongst compound heterozygotes, 3.2 (1.3–7.8) for anal fissure, fistula and abscess amongst compound heterozygotes, and 3.8 (1.6–9.2) for gastrointestinal cancer amongst homozygotes, whilst other genotypes did not have increased risk. The increased risk of gastrointestinal cancer amongst homozygotes appeared to be similar amongst both men and women and amongst those below or above 60 years, and likely included both upper gastrointestinal cancer and colorectal cancer.

Conclusions.  NOD2/CARD15 polymorphisms are not major risk factors for common gastrointestinal diseases; however, we cannot completely exclude association with appendicitis, anal fissure, fistula and abscess, and gastrointestinal cancer.
Neonatal Lipopolysaccharide Exposure Delays Puberty and Alters Hypothalamic Kiss1 and Kiss1r mRNA Expression in the Female Rat
Authors: Knox A. M. I. , Li X. F. , Kinsey‐Jones J. S. , Wilkinson E. S. , Wu X. Q. , Cheng Y.S. , Milligan S. R. , Lightman S. L. , O’Byrne K. T.
Published: June 2009

Immunological challenge experienced in early life can have long‐term programming effects on the hypothalamic‐pituitary‐adrenal axis that permanently influence the stress response. Similarly, neonatal exposure to immunological stress enhances stress‐induced suppression of the hypothalamic‐pituitary gonadal (HPG) axis in adulthood, but may also affect earlier development, including the timing of puberty. To investigate the timing of the critical window for this programming of the HPG axis, neonatal female rats were injected with lipopolysaccharide (LPS; 50 μg/kg i.p.) or saline on postnatal days 3 + 5, 7 + 9, or 14 + 16 and monitored for vaginal opening and first vaginal oestrus as markers of puberty. We also investigated the effects of neonatal programming on the development of the expression patterns of kisspeptin (Kiss1) and its receptor (Kiss1r) in hypothalamic sites known to contain kisspeptin‐expressing neuronal populations critical to reproductive function: the medial preoptic area (mPOA) and the arcuate nucleus in neonatally‐stressed animals. We determined that the critical period for a significant delay in puberty as a result of neonatal LPS exposure is before 7 days of age in the female rat, and demonstrated that Kiss1, but not Kiss1r mRNA, expression in the mPOA is down‐regulated in pre‐pubertal females. These data suggest that the mPOA population of kisspeptin neurones play a pivotal role in controlling the onset of puberty, and that their function can be affected by neonatal stress.
Projections of RFamide‐related Peptide‐3 Neurones in the Ovine Hypothalamus, with Special Reference to Regions Regulating Energy Balance and Reproduction
Authors: Qi Y. , Oldfield B. J. , Clarke I. J.
Published: June 2009

RFamide‐related peptide‐3 (RFRP‐3) is a neuropeptide produced in cells of the paraventricular nucleus and dorsomedial nucleus of the ovine hypothalamus. In the present study, we show that these cells project to cells in regions of the hypothalamus involved in energy balance and reproduction. A retrograde tracer (FluoroGold) was injected into either the arcuate nucleus, the lateral hypothalamic area or the ventromedial nucleus. The distribution and number of retrogradely‐labelled RFRP‐3 neurones was determined. RFRP‐3 neurones projected to the lateral hypothalamic area and, to a lesser degree, to the ventromedial nucleus and the arcuate nucleus. Double‐label immunohistochemistry was employed to identify cells receiving putative RFRP‐3 input to cells in these target regions. RFRP‐3 cells were seen to project to neuropeptide Y and pro‐opiomelanocortin neurones in the arcuate nucleus, orexin and melanin‐concentrating hormone neurones in the lateral hypothalamic area, as well as orexin cells in the dorsomedial nucleus and corticotrophin‐releasing hormone and oxytocin cells in the paraventricular nucleus. Neurones expressing gonadotrophin‐releasing hormone in the preoptic area were also seen to receive input from RFRP‐3 projections. We conclude that RFRP‐3 neurones project to hypothalamic regions and cells involved in regulation of energy balance and reproduction in the ovine brain.
Peripheral Lipopolysaccharide Administration Induces Cytokine mRNA Expression in the Viscera and Brain of Fever‐Refractory Mice Lacking Microsomal Prostaglandin E Synthase‐1
Authors: Nilsberth C. , Hamzic N. , Norell M. , Blomqvist A.
Published: June 2009

We examined the expression of interleukin (IL)‐1β, IL‐6 and tumour necrosis factor (TNF) α in mice lacking microsomal prostaglandin E synthase‐1 (mPGES‐1), which neither produce prostaglandin E2, nor mount a febrile response upon immune challenge. Intraperitoneal lipopolysaccharide (LPS) injection resulted in a strongly induced expression of all three cytokines in the brain and viscera, similar to wild‐type animals. Several brain regions additionally showed modest induction of receptors for these cytokines in both genotypes. Telemetric recordings of body temperature showed that the mPGES‐1 deficient mice remained afebrile upon LPS challenge, in contrast to the prominent fever displayed by the wild‐type mice. These data demonstrate that LPS‐induced cytokine expression occurs independently of prostaglandin E2, and imply that endogenously expressed IL‐1β, IL‐6, and TNFα are not pyrogenic per se, supporting the role of prostaglandin E2 as the final and obligatory mediator of LPS‐induced fever.
Leptin Modulates Spike Coding in the Rat Suprachiasmatic Nucleus
Authors: Inyushkin A. N. , Bhumbra G. S. , Dyball R. E. J.
Published: June 2009

The mammalian circadian pacemaker, the suprachiasmatic nucleus (SCN), contains receptors to the adipose tissue hormone leptin. In the present study, the effects of leptin on the electrophysiological activity of the SCN cells were characterised in vitro in rat brain slices. During extracellular recording, application of 20 nm leptin (n = 36) decreased mean spike frequency (Wilcoxon signed rank test, z = −3.390, P < 0.001) and increased the irregularity of firing measured by the entropy of the log interspike interval distribution (Student’s paired t‐test, t = 2.377, P = 0.023), but had no consistent effect on spike patterning as measured by the mutual information between adjacent log interspike intervals (z = 0.745, P = 0.456). Intracellular current‐clamp recordings (n = 25) revealed a hyperpolarising effect of 20 nm leptin on SCN neurones (z = −2.290, P = 0.022). The hyperpolarisation largely resulted from the effect of leptin on the subgroup of cells (n = 13) that generated ‘rebound’ spikes upon termination of a hyperpolarising current pulse (z = −2.697, P = 0.007). Leptin application also increased the group mean duration of the afterhyperpolarisation (n = 25, t = 2.512, P = 0.023). The effects of leptin on extracellularly recorded spike activity were consistent with the changes in membrane potential and spike shape. They suggest that leptin can directly modulate the electrical properties of SCN neurones and, in this way, contribute to the mechanism by which metabolic processes influence the circadian clock.
Progesterone Increases Dopamine Neurone Number in Differentiating Mouse Embryonic Stem Cells
Authors: Díaz N. F. , Díaz‐Martínez N. E. , Velasco I. , Camacho‐Arroyo I.
Published: June 2009

Progesterone participates in the regulation of several functions in mammals, including brain differentiation and dopaminergic transmission, but the role of progesterone in dopaminergic cell differentiation is unknown. We investigated the effects of progesterone on dopaminergic differentiation of embryonic stem cells using a five‐stage protocol. Cells were incubated with different progesterone concentrations during the proliferation (stage 4) or differentiation (stage 5) phases. Progesterone added at 1, 10 and 100 nm during stage 4 increased the number of dopamine neurones at stage 5 by 72%, 80% and 62%, respectively, compared to the control group. The administration of progesterone at stage 5 did not induce significant changes in the number of dopamine neurones. These actions were not mediated by the activation of intracellular progesterone receptors because RU 486 did not block the positive effects of progesterone on differentiation to dopaminergic neurones. The results obtained suggest that progesterone should prove useful with respect to producing higher proportions of dopamine neurones from embryonic stem cells in the treatment of Parkinson’s disease.
Frequent mitochondrial gene introgression among high elevation Tibetan megophryid frogs revealed by conflicting gene genealogies
Authors: CHEN WEI , BI KE , FU JINZHONG
Published: June 2009

Historical mitochondrial introgression causes differences between a species’ mitochondrial gene genealogy and its nuclear gene genealogy, making tree‐based species delineation ambiguous. Using sequence data from one mitochondrial gene (cytochrome b) and three nuclear genes (introns), we examined the evolutionary history of four high elevation Tibetan megophryid frog species, Scutiger boulengeri, Scutiger glandulatus, Scutiger mammatus and Scutiger tuberculatus. The three nuclear genes shared a similar history but the mitochondrial gene tree suggested a drastically different evolutionary scenario. The conflicts between them were explained by multiple episodes of mitochondrial introgression events via historical interspecific hybridization. ‘Foreign’ mitochondrial genomes might have been fixed in populations and extended through a large portion of the species’ distribution. Some hybridization events were probably as old as 10 Myr, while others were recent. An F1 hybrid was also identified. Historical hybridization events among the four species appeared to be persistent and were not restricted to the period of Pleistocene glaciation, as in several other well‐studied cases. Furthermore, hybridization involved several species and occurred in multiple directions, and there was no indication of one mitochondrial genome being superior to others. In addition, incomplete lineage sorting resulting from budding speciation may have also explained some discrepancies between the mitochondrial DNA and nuclear gene trees. Combining all evidences, the former ‘Scutiger mammatus’ appeared to be two species, including a new species. With the availability of a wide range of highly variable nuclear gene markers, we recommend using a combination of mitochondrial gene and multiple nuclear genes to reveal a complete species history.
Composition of floating weed seeds in lowland rice fields in China and the effects of irrigation frequency and previous crops
Authors: LI R H , QIANG S
Published: June 2009

The diversity and composition of floating weed seed communities were surveyed in 27 sites across the main rice‐growing regions in China with the aim of better understanding weed seed dispersal via irrigation water. Seed of 74 species, belonging to 20 families, were identified from floating matter on the water surface in lowland rice fields. Thirty‐five species from three families: Poaceae (15), Asteraceae (11), and Polygonaceae (9), accounted for 47% of all species identified. Species with seed maturing in the summer accounted for 64% of the weed seed and their mean relative abundance was 0.74. Species richness, Shannon–Wiener index and Pielou evenness index were significantly different among the floating weed seed communities. The diversity of weed seed communities in the Yangtze river valley was higher than that in other sites, and some sites were dominated by only a few weed species, such as Beckmannia syzigachne, Alopecurus aequalis, A. japonicus, and Polypogon fugax. At all sites, the dominant weed seeds reflected the dominant weed species in the previous crop. The 27 sample sites of weed seed communities can be clustered into two groups on the basis of previous crop, either lowland rice or sites with previous crops of winter fallow, winter wheat or oilseed rape. Canonical correspondence analysis (CCA) revealed that irrigation frequency, previous crop, and latitude, but not soil type or longitude, significantly affected species composition. The numbers of floating weed seed species were high in lowland rice fields; composition was affected by previous crops and irrigation frequency. Filtering irrigation water and collecting and removing floating weed seeds from the water surface could be integrated into weed management practices to control weeds in lowland rice fields.
Prospective evaluation of the time to peak effect of propofol to target the effect site in children
Authors: MUÑOZ H. R. , LEÓN P. J. , FUENTES R. S. , ECHEVARRÍA G. C. , CORTÍNEZ L. I.
Published: June 2009

Background: The plasma‐effect site equilibration rate constant (ke0) of propofol has been determined in children with the use of the time to maximum effect (tpeak), however, it has not been validated. The objective was to measure the tpeak; of propofol with two depths of anesthesia monitors in children and to evaluate these measurements with a target‐controlled infusion (TCI) system.

Methods: Unpremedicated, ASA I children from 3 to 11 years were studied. In Part 1, children were monitored simultaneously with the bispectral index (BIS) and the A‐Line ARX‐index (AAI) from the Alaris A‐Line auditory‐evoked potential monitor/2. The tpeak after a bolus dose of propofol was measured. In Part 2, the tpeak measured was used to target the effect site with a TCI system. The median (MD) and the absolute median (MDA) difference between the predicted time of peak concentration at the effect site (Ce) and the measured time of peak effect in the index of depth of anesthesia (terror) was used to evaluate the performance of the system.

Results: The BIS recordings were of a better quality than the AAI. The mean ± standard deviation tpeak was 65 ± 14 s with the BIS (n=25) and 201 ± 74 s with the AAI (n=10)(P<0.001). Validation was only performed with the BIS monitor in 40 children, yielding an MD terror of −9.5 s and an MDA terror of 10.0 s.

Conclusions: The small delay between the evolution of Ce of propofol and the observed effect suggests that this can be a useful model to target the effect site in children.
The incidence of intra‐operative awareness during general anesthesia in China: a multi‐center observational study
Authors: XU L. , WU A.‐S. , YUE Y.
Published: June 2009

Background: The incidence of awareness in patients undergoing general anesthesia is 0.1–0.2% in Western countries. The medical literatures about awareness during general anesthesia are still rare in China, but some previous studies have reported a higher incidence (1.4–6%) of intra‐operative awareness. To find out the reason why the incidence reported in China is much higher than that in Western countries, we performed a prospective, multicenter, non‐randomized observational study to determine the true incidence of intra‐operative awareness in China.

Methods: This is a prospective, non‐randomized descriptive cohort study that was conducted at 25 academic medical centers in China. Eleven thousand one hundred and eighty‐five patients were interviewed by research staff for evaluation of awareness at the first and fourth day after general anesthesia with muscle relaxation. An independent blinded committee evaluated the responses and determined whether awareness occurred. Necessary data were collected for a binary logistic regression analysis.

Results: Data from 11,101 patients were presented. Forty‐six cases (0.41%) were reported as definite awareness and 47 additional cases (0.41%) as possible awareness. Three hundred and fifty‐five patients (3.19%) had dreams during general anesthesia. Awareness was associated with increased American Society of Anesthesiologists (ASA) physical status, a previous anesthesia, and anesthesia methods of total intravenous anesthesia.

Conclusion: The incidence of intra‐operative awareness in China is approximately 0.41%, two to three times higher than that widely cited in Western countries. Inappropriately light anesthesia, and the population proportion of surgery and general anesthesia in China may account for the difference. (ClinicalTrials.gov Identifier, NCT00693875.)
Prognostic factors and outcome after drowning in an adult population
Authors: BALLESTEROS M. Á. , GUTIÉRREZ‐CUADRA M. , MUÑOZ P. , MIÑAMBRES E.
Published: June 2009

Background: Drowning remains an actual problem. Although medical assistance has improved, it still has high rates of morbidity and mortality. We set out to explore the clinical characteristics and outcome of drowning patients admitted to the intensive care unit (ICU) of tertiary‐care university hospital.

Methods: We designed a retrospective observational study to analyse all drowning patients admitted to our ICU after successful cardiopulmonary resuscitation. The study was conducted during 1 January 1992–31 December 2005. There was no exclusion. We used a univariate analysis to evaluate the effect on patient and management characteristics on survival.

Results: There were 43 patients (five children and 38 adults), with male predominance. Fifteen patients, all adults (34.9%), died. Submersion time, age, Glasgow Coma Score (GCS), pupillary reactivity and acute physiology and chronic health evaluation (APACHE II) at ICU admission were related to mortality. Non‐survivors presented a higher glycaemia level at ICU admission than survivors (P=0.005).

Conclusions: The outcome is closely related to the patient's clinical status on arrival to the hospital. We have found that submersion time, age, GCS, pupillary reactivity and APACHE II at ICU admission were related to mortality. Further research in prospective studies is needed.
Mate availability contributes to maintain the mixed‐mating system in a scolytid beetle
Authors: GOTTLIEB D. , HOLZMAN J. P. , LUBIN Y. , BOUSKILA A. , KELLEY S. T. , HARARI A. R.
Published: June 2009

We investigated the mating system and population genetic structure of the beetle, Coccotrypes dactyliperda, with life history characteristics that suggest the presence of a stable mixed‐mating system. We examined the genetic structure of seven populations in Israel and found significant departures from the Hardy–Weinberg equilibrium and an excess of homozygosity. Inbreeding coefficients were highly variable across populations, suggesting that low levels of outbreeding occur in nature. Experiments were conducted to determine whether the observed high inbreeding in these populations is the result of a reproductive assurance strategy. Females reared in the laboratory took longer to mate with males from the same population (inbreeding) than with males from a different population (outbreeding). These results suggest that females delayed inbreeding, and were more inclined to outbreed when possible. Thus inbreeding, which predominates in most populations, may be due to a shortage of mates for outbreeding rather than a preference for inbreeding. We conclude that C. dactyliperda has a mixed‐mating system that may be maintained by a reproductive assurance strategy.
Efficacy of preoperative recombinant human erythropoietin administration for reducing transfusion requirements in patients undergoing surgery for hip fracture repair. An observational cohort study
Authors: García‐Erce J. A. , Cuenca J. , Haman‐Alcober S. , Martínez A. A. , Herrera A. , Muñoz M.
Published: June 2009

Background  Preoperative anaemia is a major risk factor for allogeneic blood transfusion (ABT) in patients undergoing hip fracture repair. We investigated the efficacy of preoperative recombinant human erythropoietin (rHuEPO) administration for reducing ABT requirements in a series of consecutive hip fracture patients presenting with haemoglobin (Hb) between 10 g/dl and 13 g/dl.

Methods  The blood conservation protocol consisted of the application of a restrictive transfusion trigger (Hb < 8 g/dl) and the perioperative administration of intravenous iron sucrose (3 × 200 mg/48 h) (group 1, n = 115). Additionally, some patients received preoperative rHuEPO (40 000 IU sc) on admission to the orthopaedic ward (group 2, n = 81).

Results  Overall, 103 of 196 patients (52·5%) received at least one ABT unit (2·1 ± 1·0 U/patient). However, there were significant differences in perioperative ABT rates between groups (60% vs. 42%, for groups 1 and 2, respectively; P = 0·013). Postoperative Hb on postoperative days 7 and 30 was higher in group 2 than in group 1. In addition, in group 2, Hb levels were higher on postoperative day 30 than on admission (12·7 ± 1·0 g/dl vs. 11·9 ± 0·8 g/dl, respectively; P = 0·030). Administration of rHuEPO did not increase postoperative complications or 30‐day mortality rate. Only three mild intravenous iron adverse effects were witnessed.

Conclusions  In anaemic hip fracture patients managed with perioperative intravenous iron and restrictive transfusion protocol, preoperative administration of rHuEPO is associated with reduced ABT requirements. However, appropriate training, education and awareness are needed to avoid protocol violations and to limit further exposure to ABT and ABT‐related risks.
Large‐scale Input Matching by Urban Feral Pigeons (Columba livia)
Authors: Morand‐Ferron Julie , Lalande Émilie , Giraldeau Luc‐Alain
Published: June 2009

Ideal Free Distribution (IFD) theory predicts the number of animals choosing habitats of differing quality. Most experimental tests of the IFD have been conducted at small spatial scales (i.e. smaller than maximum daily movement of animals) by comparing the number of animals foraging at adjacent food patches of different quality. Urban pigeons (Columba livia) feed in large, open aggregations, and can distribute according to predictions of the IFD at alternative food patches. In this study, we test IFD predictions over a much larger spatial scale by comparing the abundance of urban feral pigeons at four sites spread over the city centre of Montréal, Québec, Canada, to the amount of anthropogenically provided food in each site. We found that the pigeons’ distribution among the four sites qualitatively matched that of resources available at these sites. After controlling for the effect of stochastic variation in food resources, two pair‐wise comparisons between sites indicated undermatching, one indicated matching and three indicated overmatching of consumers to resources. These results suggest that the pigeons inhabiting the downtown area of Montréal may behave as a single population that distributes qualitatively among foraging sites in proportion to the quantity of food offered, and that deviations from expectations cannot be attributed simply to stochastic variation in the food levels at the sites.
Evaluation of Juglans species for resistance to Phytophthora cinnamomi: differences in isolate virulence and response to fosetyl‐Al
Authors: Belisario A. , Galli M. , Wajnberg E.
Published: June 2009

Phytophthora is considered as an important pathogen on walnut, and severe losses are reported in European as well as in American walnut stands. Though several Phytophthora spp. are known to attack walnut, P. cinnamomi is considered the most virulent and widespread in southern Europe. Up to now, no walnut species or hybrid is known to have a high resistance level towards P. cinnamomi. Efforts are addressed in finding rootstock material graft compatible with English walnut and resistant/tolerant to P. cinnamomi. The extension of P. cinnamomi lesions on five Juglans species was studied to find out sources of resistance/tolerance to this pathogen. Walnut species clustered into two main groups, J. hindsii, J. nigra, and J. mandshurica were the less susceptible to the colonization of P. cinnamomi, while J. regia and J. sieboldiana were the most susceptible. On this account, J. mandshurica represents the best alternative as rootstock because its employment overcomes the risk of the occurrence of black line disease, it has good level of resistance to Agrobacterium temefaciens and Brenneria nigrifluens, and it is tolerant to Xanthomonas arboricola pv. juglandis. J. mandshurica is also compatible in cross‐pollinations with J. regia and J. nigra. Differences in virulence of P. cinnamomi isolates was assessed and a marked interaction between species and isolate emerged. Treatment with fosetyl‐Al by dipping was mainly efficient in reducing the length P. cinnamomi lesions, and an interaction between species and treatment was evident with the highest efficacy on J. regia and J. sieboldiana.