bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiple glacial refugia and complex postglacial range shifts of the obligatory woodland plant Polygonatum verticillatum (Convallariaceae)
Authors: Kramp K. , Huck S. , Niketić M. , Tomović G. , Schmitt T.
Published: November 2008

The phylogeography of typical alpine plant species is well understood in Europe. However, the genetic patterns of boreo‐montane species are mostly unstudied. Therefore, we analysed the AFLPs of 198 individuals of Polygonatum verticillatum over a major part of its European distribution. We obtained a total of 402 reproducible fragments, of which 96.8% were polymorphic. The average ΦST over all samples was high (73.0%). The highest number of private fragments was observed in the Cantabrian Mountains; the highest genetic diversities of the populations were detected in populations from the Alps. BAPS, Principal Coordinates and Cluster analyses revealed a deep split between the Cantabrian population and all other samples. The latter further distinguished two major groups in western and eastern Europe. These results suggest a complex biogeographical history of P. verticillatum. The Cantabrian population was most probably isolated for the longest time. Furthermore, putative glacial survival centres might have existed in the western group around the glaciated Alps and in the eastern group in the foothills of the Carpathian and Balkan mountain systems. The origin of the Scandinavian populations is still unresolved, but an origin from the southeastern Alps or the western Balkans appears the most likely scenario.
Morphological variation in the flowers of Jacaratia mexicana A. DC. (Caricaceae), a subdioecious tree
Authors: Aguirre A. , Vallejo‐Marín M. , Piedra‐Malagón E. M. , Cruz‐Ortega R. , Dirzo R.
Published: November 2008

The Caricaceae is a small family of tropical trees and herbs in which most species are dioecious. In the present study, we extend our previous work on dioecy in the Caricaceae, characterising the morphological variation in sexual expression in flowers of the dioecious tree Jacaratia mexicana. We found that, in J. mexicana, female plants produce only pistillate flowers, while male plants are sexually variable and can bear three different types of flowers: staminate, pistillate and perfect. To characterise the distinct types of flowers, we measured 26 morphological variables. Our results indicate that: (i) pistillate flowers from male trees carry healthy‐looking ovules and are morphologically similar, although smaller than, pistillate flowers on female plants; (ii) staminate flowers have a rudimentary, non‐functional pistil and are the only flowers capable of producing nectar; and (iii) perfect flowers produce healthy‐looking ovules and pollen, but have smaller ovaries than pistillate flowers and fewer anthers than staminate flowers, and do not produce nectar. The restriction of sexual variation to male trees is consistent with the evolutionary path of dioecy from hermaphrodite ancestors through the initial invasion of male‐sterile plants and a subsequent gradual reduction in female fertility in cosexual individuals (gynodioecy pathway), but further work is needed to confirm this hypothesis.
The effect of tibia morphology on vector competency of mushroom sciarid flies
Authors: Shamshad A. , Clift A. D. , Mansfield S.
Published: November 2008

Mushroom sciarid flies Lycoriella ingenua (Dufour) and Bradysia ocellaris (Comstock) are major pests of cultivated mushrooms, Agaricus bisporus (Lange) Imbach. The economic threshold of these pests is very low because they vector pathogens across mushroom beds, e.g. Verticillium fungicola which causes ‘dry bubble’ disease. Under controlled conditions, B. ocellaris transported more V. fungicola spores than L. ingenua from infected to sterile culture plates. Similar results were obtained when L. ingenua and B. ocellaris were collected from a growing room infected with V. fungicola then introduced onto sterile culture plates for 90 min. The external morphology of B. ocellaris and L. ingenua was examined using scanning electron microscopy. The micrographs showed clusters of V. fungicola spores attached to the inner side of a comb‐like row of bristles on the fore tibia of B. ocellaris whereas L. ingenua does not possess an equivalent structure on the fore tibia. These morphological differences are the most probable explanation for the greater competence of B. ocellaris as a vector of V. fungicola compared with L. ingenua.
Serum Profiles of Pregnancy‐Associated Glycoprotein, Oestrone Sulphate and Progesterone During Gestation and Some Factors Influencing the Profiles in Ethiopian Borana and Crossbred Cattle
Authors: Lobago F , Bekana M , Gustafsson H , Beckers JF , Yohannes G , Aster Y , Kindahl H
Published: November 2008

Contents

This study presents serum concentrations of pregnancy‐associated glycoprotein (PAG), oestrone sulphate (E1‐S) and progesterone (P4), and the effects of some dam and foetus‐related factors on these profiles during gestation in Borana and crossbred cattle. The PAG concentrations at 4th week post‐conception ranged from 1.5–5.5 and 2.1–4.7 ng/ml in Borana (n = 6) and crossbred (n = 8) cattle, respectively. The mean PAG concentrations increased progressively from 4th to 33rd week of gestation (from 3.3–173 ng/ml for Borana and 4.2–240 ng/ml for crossbred cattle) and reached peak around calving. Breed, parity status, dam body weight, foetal sex and foetal birth weight significantly influenced the PAG concentrations. After delivery, the PAG concentrations declined steadily to 5.7 ng/ml in Borana (n = 7) and 3.9 ng/ml in crossbred (n = 6) cattle 10 weeks post‐partum. The serum E1‐S concentrations at 17th week of pregnancy ranged from 0.3–2.6 and 0.9–5.7 ng/ml in Borana (n = 8) and crossbred (n = 9) cattle, respectively. The mean E1‐S concentrations increased progressively from 17th to 33rd week of gestation (from 1.1–4.6 ng/ml for Borana and 2.7–10.8 ng/ml for crossbred). Breed, parity status, dam body weight and foetal sex significantly influenced E1‐S concentrations. The P4 concentrations at 4th week of pregnancy ranged from 3.2–5.1 and 1.7–8.9 ng/ml in Borana (n = 6) and crossbred (n = 8) cattle, respectively. The P4 level remained elevated throughout pregnancy. This study indicated that the serum PAG and P4 concentrations at 4th and E1‐S approximately 17th week of pregnancy were above the cut‐off value for pregnancy test and the hormonal profiles observed were comparable to the previous reports. Furthermore, the PAG and E1‐S profiles were considerably influenced by factors such as breed, weight and parity status of the dam, and foetal sex and foetal birth weight (only PAG).
An Abortion of Monozygotic Twins in a Warmblood Mare
Authors: Govaere J , Hoogewijs M , De Schauwer C , Van Zeveren A , Smits K , Cornillie P , De Kruif A
Published: November 2008

Contents

Naturally occurring monozygotic twins are extremely rare in the horse. This paper describes an abortion in a mare after 260 days of pregnancy with monozygotic twins, one a fresh foal and the other a mummified foal.
Systemic Concentrations of Endogenous and Exogenous FSH in Anoestrous Ewes Superstimulated with Folltropin®‐V
Authors: Bartlewski PM , Fuerst KJ , Alexander BD , King WA
Published: November 2008

Contents

The synchronization of follicular waves with medroxyprogesterone acetate (MAP) and oestradiol‐17β (E2‐17β) prior to ovarian superstimilation in anoestrous ewes reduces the variability in superovulatory responses by an unknown mechanism. Follicle stimulating hormone (FSH) is a primary promoter of antral follicular development, but the relevance of circulating FSH concentrations to the superovulation performance in ewes has not been examined. Eighteen anoestrous Rideau Arcott ewes (May–June) were superovulated with Folltropin®‐V (porcine FSH), with (n = 8; treated ewes) or without (n = 10; control ewes) a single i.m. dose of 350 μg of E2‐17β, given on the sixth day of a 14‐day treatment with MAP‐releasing intravaginal sponges (60 mg). The superovulatory treatment, begun 6 days after E2‐17β injection, consisted of six i.m. applications of Folltropin®‐V given twice daily (at 08:00 and 16:00 h), followed by an i.m. injection of GnRH (50 μg). Blood samples collected every 8 h throughout the 3‐day treatment, were analysed by radioimmunoassays for concentrations of ovine and porcine FSH, using species‐specific standards and primary antibodies. Serum concentrations of oFSH were greater (p < 0.05) in the controls compared to treated ewes at 40, 64 and 72 h and the variability in mean oFSH concentrations was greater (p < 0.05) in control ewes at 40, 48, 64 and 72 h after the 1st Folltropin®‐V injection. There were no differences (p > 0.05) between the two groups in serum concentrations of pFSH. Significant correlations were recorded between the number of corpora lutea (CL) and oFSH concentrations at 8 h (r = 0.72, p < 0.05), 16 h (r=0.63, p < 0.05) and 64 h (r = 0.84, p < 0.01) after the 1st Folltropin®‐V injection. The total number of recovered embryos was positively correlated to oFSH concentrations at 56 h (r = 0.69, p < 0.05). We concluded that changes in endogenous FSH concentrations during ovarian superstimulation with pFSH might contribute to the variability in superovulatory responses in ewes.
Buffalo (Bubalus bubalis) Pre‐antral Follicle Population and Ultrastructural Characterization of Antral Follicle Oocyte
Authors: Mondadori RG , Santin TR , Fidelis AAG , Porfírio EP , Báo SN
Published: November 2008

Contents

The main objectives of the present study were to determine the ultrastructural modifications occurring in the oocyte during late folliculogenesis and to estimate pre‐antral follicle population in buffalo. Half the collected ovaries were fixed and prepared for optic microscopy; the antral follicles from the other ovaries were measured and individually punctured. The cumulus–oocyte complexes (COCs) were processed for transmission electron microscopy. The number of pre‐antral follicles in buffalo ovaries was estimated at 19 819 structures. Cumulus–oocyte complexes derived from 1‐mm antral follicle had an eccentrical nucleus and compact corona radiata, ooplasm vilosities were fully embedded in zona pellucida (ZP) and a well‐defined junction could be observed. Mitochondria were predominantly round and well distributed in ooplasm, as were small lipid vacuoles. In COCs derived from 2‐mm antral follicles, the initial formation of perivitelline space was observed. The nucleus was peripherally located and the number of pleomorphic mitochondria increased. Cortical granules were clustered at oocyte periphery and lipid vacuoles increased in number and size. In COCs derived from 6‐mm antral follicles, the organelles were located mainly in the perinuclear region. Golgi complexes and smooth endoplasmic reticulum (SER) were more developed. Mitochondria migrated to the cortical region and lipid vacuoles migrated to the medullar region. In COCs derived from 10‐mm antral follicles, the lipid vacuoles coalesced and occupied the medullar region of the oocyte, together with a well‐developed SER. Mitochondria were pleomorphic and located at the oocyte periphery. In conclusion, the morphological differences described in this paper could be responsible for some functional differences observed in in vitro embryo production and follicular dynamics for buffalo, when compared with cattle.
INVOLVEMENT OF MITOCHONDRIAL PERMEABILITY TRANSITION, GLUTATHIONE STATUS, PENTOSE PHOSPHATE PATHWAY AND OXIDATIVE DAMAGE IN THE PROTECTIVE EFFECT OF FASTING ON THE ISCHAEMIC‐REPERFUSED RAT HEART
Authors: Marina Prendes María G , González Marcela S , Torresín María E , Hermann Romina , Pascale Natalia G , Del Mar Jaitovich María , Savino Enrique A , Varela Alicia
Published: November 2008

Fasting, which increases the catabolism of fatty acids, gives functional protection to the ischaemic–reperfused heart. To obtain further knowledge of this cardioprotective effect, changes in mitochondrial permeability transition (MPT) were measured by the entrapment of 2‐deoxy‐[3H]‐glucose (2‐DG). We also assessed whether MPT is associated with changes in glutathione status, the activity of glucose‐6‐phosphate‐dehydrogenase (G6PDH) and tissue oxidative damage, estimated by the measurement of Thiobarbituric acid‐reactive substances (TBARS).

Spontaneously beating hearts of fed and 24 h fasted rats were Langendorff perfused with Krebs’–Ringer bicarbonate solution (10 mmol/L glucose) and exposed to 25 min global ischaemia, followed by 30 min reperfusion.

Ischaemia–reperfusion resulted in a fourfold increase in mitochondrial entrapment of 2‐DG in the fed group. This response was 29% lower in the fasted group, but there were no concomitant changes in total retention of 2‐DG in the heart. Fasting increased the activity of G6PDH by a factor of 1.4 and caused a 2.8‐fold increase in the ratio of reduced glutathione to oxidized glutathione (GSH : GSSG) at the end of the pre‐ischaemic period. Ischaemia–reperfusion did not affect G6PDH activity, but reduced the GSH : GSSG ratio in both the fed and fasted groups by 50%. Therefore, the GSH : GSSG ratio remained higher in the fasted group. Fasting also decreased cellular levels of TBARS by approximately 25%. Lipolysis of endogenous triacylglycerol was increased during the pre‐ischaemic period in the fasted group.

These data suggest that the enhancement of fatty acid catabolism that occurs in fasting activates mechanisms that tend to reduce oxidative damage and limit MPT.
ROLE OF l‐ARGININE IN NITRIC OXIDE PRODUCTION IN HEALTH AND HYPERTENSION
Authors: Rajapakse Niwanthi W , Mattson David L
Published: November 2008

l‐Arginine is the substrate for vascular nitric oxide (NO) formation. Under normal physiological conditions, intracellular l‐arginine levels far exceed the Km of NO synthase for l‐arginine. However, endogenous NO formation is dependent on extracellular l‐arginine concentrations, giving rise to the concept of the ‘l‐arginine paradox’.

Nitric oxide production in epithelial and endothelial cells is closely coupled to cellular l‐arginine uptake, indicating that l‐arginine transport mechanisms play a major role in the regulation of NO‐dependent function.

Consistent with the data in endothelial and epithelial cells are functional data indicating that exogenous l‐arginine can increase renal vascular and tubular NO bioavailability and thereby influence kidney perfusion, function and arterial pressure. The integrated effect of increased cellular l‐arginine transport is to lower arterial pressure. Therefore, the use of l‐arginine in the treatment of hypertension warrants investigation.

Low NO bioavailability is central to the development and maintenance of hypertension and to related endothelial dysfunction and target organ damage. We propose that l‐arginine can interrupt the vicious cycle that initiates and maintains low NO in hypertension by increasing the formation of NO.
HYDROGEN PEROXIDE ENHANCES OSTEOPONTIN EXPRESSION AND MATRIX METALLOPROTEINASE ACTIVITY IN AORTIC VASCULAR SMOOTH MUSCLE CELLS
Authors: Hu Tao , Luan Ronghua , Zhang Haifeng , Lau Wayne B , Wang Qiong , Zhang Yao , Wang Hai‐Chang , Tao Ling
Published: November 2008

Restenosis after percutaneous coronary intervention (PCI) is a major clinical complication. However, the underlying mechanisms remain poorly understood. The present aim of the present study was to test the hypothesis that reactive oxygen species (ROS) enhance osteopontin (OPN) expression and increase matrix metalloproteinase (MMP)‐2 activity (two major factors that contribute to restenosis) in aortic vascular smooth muscle cells (VSMC), thus facilitating restenosis.

Primary cultured rat aortic VSMC were exposed to different concentrations (10, 50 and 100 µmol/L) of H2O2. The expression of OPN mRNA and protein was determined by reverse transcription–polymerase chain reaction and Western blotting, respectively. The activity of MMP‐2 was determined by gelatin zymography.

The expression of OPN mRNA and protein in VSMC was enhanced by H2O2 in a dose‐dependent manner. In addition, H2O2 at all concentrations tested (which are comparable to those seen in diabetic vascular tissues) significantly increased MMP‐2 activity in VSMC.

Because vascular ROS production is significantly increased in patients with ischaemic disease and OPN and MMP‐2 have been shown to play critical role in restenosis, the results of the present study strongly suggest that a ROS‐initiated and OPN‐ and MMP‐2‐mediated signalling pathway may play an important role in accelerated restenosis after PCI in patients with ischaemic disease. Therefore, the H2O2–OPN/MMP‐2 system may be a new therapeutic target in reducing restenosis in patients undergoing PCI.
PREVENTIVE AND CURATIVE EFFECTS OF ETIFOXINE IN A RAT MODEL OF BRAIN OEDEMA
Authors: Girard Philippe , Pansart Yannick , Gillardin Jean‐Marie
Published: November 2008

The aim of the present study was to test the hypothesis that increasing GABAergic neurotransmission is involved in the prevention or treatment of brain oedema. The study was conducted in the well‐established rat triethyltin (TET) model of brain oedema and examined the effects of etifoxine, a compound that increases GABAergic neurotransmission through multiple mechanisms, including neurosteroid synthesis.

Daily oral administration of 3 mg/kg per day TET for 5 consecutive days strongly perturbed rat behaviour and induced reproducible cerebral oedema. Coadministration of etifoxine (2 × 25 or 2 × 50 mg/kg per day, p.o.) over the 5 days of TET treatment blocked the development of brain oedema and the increase in brain sodium content induced by TET, as well as reducing the increase in brain chloride content. Moreover, etifoxine inhibited the decrease in bodyweight, the neurological deficit and the altered locomotor activity induced by TET. At a lower dose (2 ↔ 10 mg/kg per day, p.o.), etifoxine did not have any preventive effects.

To examine the curative effects of etifoxine, it was administered from the 4th day of TET treatment for 5 consecutive days, when brain oedema was already established. In these experiments, etifoxine (2 ↔ 50 mg/kg per day, p.o.) significantly reduced cerebral oedema and the outcomes induced by TET treatment. Moreover, etifoxine reduced the mortality in response to TET treatment.

In conclusion, because etifoxine has a good safety profile as an anxiolytic, the results of the present study suggest that it is worth further clinical investigation as a neuroprotectant.
ANGIOTENSIN‐CONVERTING ENZYME INHIBITORS IMPROVE HEPATIC STEATOSIS BY MODULATING EXPRESSION OF TUMOUR NECROSIS FACTOR‐α, INTERLEUKIN‐6 AND ADIPONECTIN RECEPTOR‐2 IN RATS WITH TYPE 2 DIABETES
Authors: Zhang Xia , Li Zhong‐Zhuan , Liu Dong‐Fang , Xu Xin , Mei Zhe‐Chuan , Shen Wei
Published: November 2008

Angiotensin‐converting enzyme inhibitors (ACEI) are hypotensive drugs that have been shown to prevent Type 2 diabetes mellitus (T2DM) in high‐risk individuals. However, in T2DM, the effects of ACEI on hepatic steatosis are not known. The aim of the present study was to examine the effects of ACEI on changes in liver histology and hepatic mRNA expression of adipokines in rats with T2DM.

Thirty‐six rats were divided into a normal control group, a T2DM group and a fosinopril‐treated group. After six weeks of treatment with 5 mg/kg per day fosinopril, an ACEI, changes in liver histology, serum fasting glucose (FG), insulin, triglyceride (TG), total cholersterol (TC), alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumour necrosis factor (TNF)‐α, interleukin (IL)‐6, adiponectin were evaluated, as was hepatic TNF‐α, IL‐6 and adiponectin receptor‐2 (adipoR2) mRNA expression.

The degree of hepatic steatosis and inflammation, serum FG, insulin, TG, TC, ALT, TNF‐α and IL‐6 concentrations and hepatic TNF‐α and IL‐6 mRNA expression were significantly higher in rats with T2DM than in normal controls. Serum adiponectin concentrations and hepatic adipoR2 mRNA expression in rats with T2DM were significantly lower than in normal controls. Fosinopril significantly reduced the degree of hepatic steatosis, serum FG, insulin, ALT, TNF‐α and IL‐6 concentrations and hepatic TNF‐α and IL‐6 mRNA expression. Fosinopril significantly increased serum adiponectin concentrations and hepatic adipoR2 mRNA expression.

In conclusion, the ACEI improved insulin sensitivity and hepatic steatosis in rats with T2DM by increasing circulating adiponectin and hepatic adipoR2 levels, in addition to reducing pro‐inflammatory cytokine levels in the circulation and liver.
Probiotic administration alters the gut flora and attenuates colitis in mice administered dextran sodium sulfate
Authors: Nanda Kumar Navalpur S , Balamurugan Ramadass , Jayakanthan Kabirdoss , Pulimood Anna , Pugazhendhi Srinivasan , Ramakrishna Balakrishnan S
Published: November 2008

Background:  Probiotics are used in the therapy of inflammatory bowel disease. This study aimed to determine whether prior administration of probiotic lactobacilli and bifidobacteria would prevent disease and change gut flora in an animal model of colitis.

Methods:  Swiss albino mice received a probiotic mixture (four Lactobacillus and four Bifidobacterium species) or medium (control) for a week prior to induction of colitis by oral 4% dextran sodium sulfate (DSS) for seven days. Appropriate non‐colitis controls were used. Histological damage was assessed (n = 5 per group), as was expression of mRNA for tumor necrosis factor (TNF)‐α, interferon (IFN)‐γ, transforming growth factor (TGF)‐β1 and SOCS‐1 in the colonic mucosa (n = 6 per group). Secretion of TNF‐α was measured in distal colon organ culture (n = 5–6 per group). Levels of Bacteroides, Bifidobacterium, and Lactobacillus acidophilus in feces were quantified by real time polymerase chain reaction (PCR) targeting 16S rDNA.

Results:  Compared to untreated DSS colitis, probiotic treatment significantly reduced weight loss (P < 0.05), shifted histological damage to lesser grades of severity (P < 0.001), reduced mRNA expression of TNF‐α and TGF‐β1 (P < 0.05), and down‐regulated production of TNF‐α from distal colon explants (P < 0.05). Colitis induced a significant reduction in the relative proportions of Bifidobacterium, Bacteroides and Lactobacillus acidophilus group bacteria in feces, and these levels were significantly increased in probiotic‐treated mice compared to DSS mice (P < 0.001).

Conclusion:  Prior administration of probiotic bacteria reduced mucosal inflammation and damage in DSS‐induced colitis. DSS colitis was associated with significant changes in the fecal anaerobic bacterial flora and these changes were modulated by administration of probiotic bacteria.
Genetic relationship between Echinochloa crus‐galli and Echinochloa oryzicola accessions inferred from internal transcribed spacer and chloroplast DNA sequences
Authors: AOKI DAISUKE , YAMAGUCHI HIROFUMI
Published: November 2008

Barnyardgrass, hexaploid Echinochloa crus‐galli, is considered to arise from the hybridization between tetraploid Echinochloa oryzicola and an unknown diploid species. The genetic relationship between E. crus‐galli and E. oryzicola was examined to investigate the position of E. oryzicola in the evolutionary process of E. crus‐galli, based on the nuclear DNA internal transcribed spacer (ITS) and the chloroplast cpDNA trnT‐L, trnL intron, and trnL‐F regions. New World E. crus‐galli was clearly separated from Eurasian E. crus‐galli and showed a close relationship to the American taxa, Echinochloa crus‐pavonis and Echinochloa walteri, in both the ITS and chloroplast DNA. The nrDNA ITS sequences indicated no differentiation between the Eurasian E. crus‐galli and E. oryzicola, in contrast to their clear divergence in the cpDNA sequence. The present results suggest that E. oryzicola is the male donor of E. crus‐galli.
The Modified Wöhler Curve Method applied along with the Theory of Critical Distances to estimate finite life of notched components subjected to complex multiaxial loading paths
Authors: SUSMEL L. , TAYLOR D.
Published: November 2008

This paper is concerned with the use of the Modified Wöhler Curve Method (MWCM) applied in conjunction with the Theory of Critical Distances (TCD) to estimate fatigue lifetime of mechanical components subjected to multiaxial cyclic loading and experiencing stress concentration phenomena. In more detail, our engineering approach takes as its starting point the idea that accurate estimates can be obtained by simply assuming that the value of the critical length, LM, to be used to evaluate fatigue damage in the medium–cycle multiaxial fatigue regime is a function of the number of cycles to failure, Nf. In other words, the MWCM, which is a bi‐parametrical critical plane approach, is suggested here to be applied by directly post‐processing the linear‐elastic stress state damaging a material point whose distance from the notch tip increases as Nf decreases. According to the main feature of the TCD, the above LM versus Nf relationship is assumed to be a material property to be determined experimentally: such an hypothesis results in a great simplification of the fatigue assessment problem because, for a given material, the same critical length can be used to estimate fatigue damage independent of the considered geometrical feature. The accuracy of the devised approach was checked by analysing about 150 experimental results we generated by testing V‐notched cylindrical samples made of a commercial cold‐rolled low‐carbon steel. The above specimens were tested under in‐phase and out‐of‐phase combined tension and torsion, considering the damaging effect of superimposed static stresses as well. Moreover, in order to better check its accuracy in assessing notched components subjected to complex loading paths, our method was also applied to several data sets taken from the literature. This extensive validation exercise allowed us to prove that the MWCM applied along with the TCD is successful in estimating medium‐cycle multiaxial fatigue damage (Nf values in the range 104–106), resulting in predictions falling within the widest scatter band between the two used to calibrate the method itself. Such a high accuracy level is very promising, especially in light of the fact that the proposed approach predicts multiaxial fatigue lifetime by post‐processing the linear elastic stress fields in the fatigue process zone: this makes our method suitable for being used to assess real components by performing the stress analysis through simple linear‐elastic FE models.
How does climate warming affect plant‐pollinator interactions?
Authors: Hegland Stein Joar , Nielsen Anders , Lázaro Amparo , Bjerknes Anne‐Line , Totland Ørjan
Published: November 2008

Climate warming affects the phenology, local abundance and large‐scale distribution of plants and pollinators. Despite this, there is still limited knowledge of how elevated temperatures affect plant‐pollinator mutualisms and how changed availability of mutualistic partners influences the persistence of interacting species. Here we review the evidence of climate warming effects on plants and pollinators and discuss how their interactions may be affected by increased temperatures. The onset of flowering in plants and first appearance dates of pollinators in several cases appear to advance linearly in response to recent temperature increases. Phenological responses to climate warming may therefore occur at parallel magnitudes in plants and pollinators, although considerable variation in responses across species should be expected. Despite the overall similarities in responses, a few studies have shown that climate warming may generate temporal mismatches among the mutualistic partners. Mismatches in pollination interactions are still rarely explored and their demographic consequences are largely unknown. Studies on multi‐species plant‐pollinator assemblages indicate that the overall structure of pollination networks probably are robust against perturbations caused by climate warming. We suggest potential ways of studying warming‐caused mismatches and their consequences for plant‐pollinator interactions, and highlight the strengths and limitations of such approaches.
Prostate‐specific antigen ‘bounce’ after permanent 125I‐implant brachytherapy in Japanese men: a multi‐institutional pooled analysis
Authors: Satoh Takefumi , Ishiyama Hiromichi , Matsumoto Kazumasa , Tsumura Hideyasu , Kitano Masashi , Hayakawa Kazushige , Ebara Shin , Nasu Yasutomo , Kumon Hiromi , Kanazawa Susumu , Miki Kenta , Egawa Shin , Aoki Manabu , Toya Kazuhito , Yorozu Atsushi , Nagata Hirohiko , Saito Shiro , Baba Shiro
Published: November 2008

OBJECTIVE

To examine the incidence, timing, and magnitude of the prostate‐specific antigen (PSA) level ‘bounce’ after permanent prostate brachytherapy (BT) and correlate the PSA bounce with clinical and dosimetric factors in Japanese patients with prostate cancer.

PATIENTS AND METHODS

A multi‐institutional pooled analysis was carried out in 388 consecutive patients with T1–T2N0M0 prostate cancer treated with 125I‐seed implant BT with no hormonal therapy or external beam radiotherapy. All patients had ≥1 year of follow‐up and at least three follow‐up PSA level measurements. Three definitions of PSA bounce were used: definition A, a PSA level rise of 0.1 ng/mL; definition B, a PSA level rise of 0.4 ng/mL; and definition C, a PSA level rise of 35% over the previous value, followed by a subsequent fall.

RESULTS

The actuarial likelihood of having PSA bounce at 24 months was 50.8% for definition A, 23.5% for definition B, and 19.4% for definition C. The median time to develop PSA bounce was 12 months for definition A, 18 months for definition B, and 18 months for definition C. There was a PSA bounce magnitude of 2 ng/mL in 5.3% of patients, and 95.3% of PSA bounce occurred within 24 months after 125I‐BT. Among the before and after 125I‐BT factors, clinical stage, initial PSA level, and Gleason score did not predict for PSA bounce using any definition; only being younger predicted for PSA bounce on multivariate analysis (P < 0.001).

CONCLUSIONS

PSA bounce is a common phenomenon after 125I‐BT and occurred at a rate of 19–51% in the Japanese men who underwent 125I‐BT, depending on the definition used. It is more common in younger patients, and early PSA bounce should be considered when assessing a patient with a rising PSA level after 125I‐BT, before implementing salvage interventions. Furthermore, PSA bounce magnitude might be lower in Japanese than in Caucasian patients.
Nucleocytoplasmic transit of human α1‐antichymotrypsin in tobacco leaf epidermal cells†
Authors: Benchabane Meriem , Saint‐Jore‐Dupas Claude , Faye Loïc , Gomord Véronique , Michaud Dominique
Published: November 2008

Recently, we have observed a nuclear localization for human α1‐antichymotrypsin (AACT) expressed in the cytosol of transgenic Bright Yellow‐2 (BY‐2) tobacco cultured cells (see accompanying paper:Benchabane, M., Saint‐Jore‐Dupas, C., Bardor, M., Faye, L., Michaud, D. and Gomord, V. (2008a)Targeting and post‐translational processing of human α1‐antichymotrypsin in BY‐2 tobacco cultured cells.Plant Biotechnol. J. doi: 10.1111/j.1467‐7652.2008.00382.x). In the present article, we assess whether the intrinsic DNA‐binding activity of AACT can explain its nuclear localization, and whether this same activity has an impact on its protease inhibitory potency and stabilityin planta. An engineered form of AACT with no DNA‐binding activity, rAACTΔK, was compared with the wild‐type polypeptide, rAACT, in terms of chymotrypsin inhibitory potency, stabilityin plantaand distribution in tobacco cells. In accordance with available data reporting distinct sites for protease inhibition and DNA binding, rAACT and rAACTΔK showed similar antichymotrypsin activity, similar to the activity of native AACT purified from human plasma. As observed for AACT in BY‐2 tobacco cells, a green fluorescent protein (GFP)‐AACT fusion transiently expressed in the cytosol of tobacco leaf epidermal cells was detected mainly in the nucleus by confocal laser microscopy. By contrast, rAACTΔK expressed as a GFP fusion showed a balanced distribution between the cytosol and the nucleus, similar to the distribution pattern of free GFP exhibiting no DNA‐binding affinity. In line with immunodetection data showing higher accumulation levels for GFP‐AACT in tobacco leaf cells, rAACTΔK was more susceptible than rAACT to tryptic digestion in the presence of DNA. Overall, these observations suggest the following: (i) a retention effect of DNA on AACT in the nucleus; and (ii) a stabilizing effect of the AACT–DNA interaction on rAACT challenged with non‐target proteases, which, possibly, may be useful in protecting this protein in plant expression platforms.
Enhanced triterpene saponin biosynthesis and root nodulation in transgenic barrel medic (Medicago truncatula Gaertn.) expressing a novel β‐amyrin synthase (AsOXA1) gene
Authors: Confalonieri Massimo , Cammareri Maria , Biazzi Elisa , Pecchia Paola , Fevereiro Manuel Pedro Salema , Balestrazzi Alma , Tava Aldo , Conicella Clara
Published: November 2008

Triterpene saponins are a group of bioactive compounds abundant in the genus Medicago, and have been studied extensively for their biological and pharmacological properties. In this article, we evaluated the effects of the ectopic expression of AsOXA1 cDNA from Aster sedifolius on the production of triterpene saponins in barrel medic (Medicago truncatula Gaertn.). AsOXA1 cDNA encodes β‐amyrin synthase, a key enzyme involved in triterpene saponin biosynthesis. One of the four transgenic lines expressing AsOXA1 accumulated significantly larger amounts of some triterpenic compounds in leaf and root than did control plants. In particular, the leaf exhibited significantly higher levels of bayogenin, medicagenic acid and zanhic acid. The amounts of medicagenic acid and zanhic acid, which represent the core of the M. truncatula leaf saponins, were 1.7 and 2.1 times higher, respectively, than the amounts extracted from the control line. In root, the production of bayogenin, hederagenin, soyasapogenol E and 2β‐hydroxyoleanolic acid was increased significantly. The increase in the total amounts of triterpenic compounds observed in the leaves of transgenic lines correlated with the AsOXA1 expression level. Interestingly, the plants expressing AsOXA1 showed, under different growth conditions, improved nodulation when compared with the control line. Nodulation enhancement was also accompanied by a significant change in the soyasapogenol B content. Our results indicate that the ectopic expression of AsOXA1 in barrel medic leads to a greater accumulation of triterpene saponins and enhanced root nodulation.
Plant recombinant erythropoietin attenuates inflammatory kidney cell injury
Authors: Conley Andrew J. , Mohib Kanishka , Jevnikar Anthony M. , Brandle Jim E.
Published: November 2008

Human erythropoietin (EPO) is a pleiotropic cytokine with remarkable tissue‐protective activities in addition to its well‐established role in red blood cell production. Unfortunately, conventional mammalian cell cultures are unlikely to meet the anticipated market demands for recombinant EPO because of limited capacity and high production costs. Plant expression systems may address these limitations to enable practical, cost‐effective delivery of EPO in tissue injury prevention therapeutics. In this study, we produced human EPO in tobacco and demonstrated that plant‐derived EPO had tissue‐protective activity. Our results indicated that targeting to the endoplasmic reticulum (ER) provided the highest accumulation levels of EPO, with a yield approaching 0.05% of total soluble protein in tobacco leaves. The codon optimization of the human EPO gene for plant expression had no clear advantage; furthermore, the human EPO signal peptide performed better than a tobacco signal peptide. In addition, we found that glycosylation was essential for the stability of plant recombinant EPO, whereas the presence of an elastin‐like polypeptide fusion had a limited positive impact on the level of EPO accumulation. Confocal microscopy showed that apoplast and ER‐targeted EPO were correctly localized, and N‐glycan analysis demonstrated that complex plant glycans existed on apoplast‐targeted EPO, but not on ER‐targeted EPO. Importantly, plant‐derived EPO had enhanced receptor‐binding affinity and was able to protect kidney epithelial cells from cytokine‐induced death in vitro. These findings demonstrate that tobacco plants may be an attractive alternative for the production of large amounts of biologically active EPO.
Price Transmission and Market Integration in Oyo State, Nigeria
Authors: Oladapo M.O. , Momoh S.
Published: November 2008

Abstract:  The paper tests the market integration of the main staple agricultural commodities in Oyo State. Monthly prices in covering a period of 8 years (1994–2001) were obtained from Oyo State Agricultural Development Programme (OYSADP) and analysed using the Ravallion Model. The study also calculated the Indices of Market Concentration (IMC) to measure the degree of spatial market integration. The IMCs for cassava, yam, white maize and yellow maize were 0.3074, 0.0814, 0.02712 and 0.1648 respectively. The IMCs imply high short‐run market integration between the reference and rural markets. The market integration indices confirm that price changes in the urban markets (Bodija and Ilora) translated to changes in the price of cassava, yam, maize, yellow maize in rural markets (Akanran, Towobowo, Anko, Irepodun, Oje, Kajola, Akala and Aberu). It is concluded that agricultural commodity arbitrage is working. The degree of market integration can be enhanced by the provision of not only transport infrastructure but by provision of adequate formal marketing information and standardization of weights and measures in the system.
The myths about e‐learning in higher education
Authors: Njenga James Kariuki , Fourie Louis Cyril Henry
Published: November 2008

Proponents have marketed e‐learning by focusing on its adoption as the right thing to do while disregarding, among other things, the concerns of the potential users, the adverse effects on users and the existing research on the use of e‐learning or related innovations. In this paper, the e‐learning‐adoption proponents are referred to as thetechnopositivists. It is argued that most of thetechnopositivistsin the higher education context are driven by a personal agenda, with the aim of propagating atechnopositivist ideologyto stakeholders.The technopositivist ideologyis defined as a ‘compulsive enthusiasm’ about e‐learning in higher education that is being created, propagated and channelled repeatedly by the people who are set to gain without giving the educators the time and opportunity to explore the dangers and rewards of e‐learning on teaching and learning. Ten myths on e‐learning that thetechnopositivistshave used are presented with the aim of initiating effective and constructive dialogue, rather than merely criticising the efforts being made.
You Can't Always Get What You Want
Authors: Brandone Amanda C. , Wellman Henry M.
Published: November 2008

At what age do infants understand that goals exist independently of the actions that result from them? Exploring infants' understanding of failed intentional actions—when the goal of the action is unfulfilled and thus not apparent in the actor's movements—is a critical step in answering this question. Using a visual habituation paradigm, we assessed when infants understand that a failed intentional action is goal directed and whether an understanding of successful intentional actions (actions that do overtly attain their goals) precedes an understanding of failed intentional actions. Results demonstrated that 10- and 12-month-olds recognized the goal directedness of both successful and failed reaching actions. Eight-month-olds also recognized the goal directedness of successful actions, but not of unsuccessful attempts. Thus, by the end of the 1st year of life, infants possess an impressive understanding of intentional action, and an understanding of failed intentional actions follows an earlier understanding of successful ones.
Cognitive Mechanisms Underlying Recovered-Memory Experiences of Childhood Sexual Abuse
Authors: Geraerts Elke , Lindsay D. Stephen , Merckelbach Harald , Jelicic Marko , Raymaekers Linsey , Arnold Michelle M. , Schooler Jonathan W.
Published: November 2008

People sometimes report recovering long-forgotten memories of childhood sexual abuse. The memory mechanisms that lead to such reports are not well understood, and the authenticity of recovered memories has often been challenged. We identified two subgroups of people reporting recovered memories of childhood sexual abuse. These subgroups differed dramatically in their cognitive profiles: People who recovered memories of abuse through suggestive therapy exhibited a heightened susceptibility to the construction of false memories, but showed no tendency to underestimate their prior remembering. Conversely, people who recovered memories of abuse spontaneously showed a heightened proneness to forget prior incidences of remembering, but exhibited no increased susceptibility to false memories. This double dissociation points to mechanisms that underlie recovered-memory experiences and indicates that recovered memories may at times be fictitious and may at other times be authentic.
STAKEHOLDERS AND PERSPECTIVISM IN QUALITATIVE POLICY EVALUATION: A REALIST REFLECTION
Authors: PORTER SAM , SHORTALL SALLY
Published: November 2008

This paper examines the epistemological bases for the inclusion of stakeholders in policy research. While it concedes that the input of stakeholders provides essential expert and experiential knowledge for the understanding of complex policies and programmes, it contends that the approach which assumes that all interpretations of policy including those of stakeholders should be afforded equal validity, which we term relativist perspectivism, undermines the possibility of robust research by allowing power to replace methodological rigour as the primary research dynamic. It is noted that this problem tends to be more acute when the research is qualitative. A study into the gendered effects of Common Agricultural Policy reforms is used as an illustrative example of how research can be compromised by relativist perspectivism. It is argued that realist research methodologies uniquely provide the capacity to maintain epistemological robustness, while also being able to take due account of the perspectives of stakeholders.
The College Wage Premium and the Expansion of Higher Education in the UK*
Authors: Walker Ian , Zhu Yu
Published: November 2008

This paper reports estimates of the UK “college premium” for young graduates across successive cohorts from large cross‐section datasets for the UK pooled from 1994 to 2006—a period when the higher education participation rate increased dramatically. The growth in relative labour demand suggests that graduate supply considerably outstripped demand which ought to imply a fall in the premium. We find no significant fall for men and even a large, but insignificant, rise for women. Quantile regression results reveal a fall in the premium only for men in the bottom quartile of the distribution of unobserved skills.
Compensating Wage Differentials for Schooling Risk in Denmark*
Authors: Diaz‐Serrano Luis , Hartog Joop , Nielsen Helena Skyt
Published: November 2008

In this paper we analyse the association between wage differentials and risk using detailed information on length and type of education as seen in Danish administrative registers. Our contribution to the literature is that we distinguish between transitory (time‐series) and permanent (cross‐sectional) income shocks, and estimate the compensation for both sorts of risk. We find that wage risk in a given education cell is associated with higher wages, while skewness is associated with lower wages. As a robustness check, we see that ad hoc risk measures based on earnings‐mobility indicators confirm these findings.
Signalling or Human Capital: Evidence from the Finnish Polytechnic School Reform
Authors: Hämäläinen Ulla , Uusitalo Roope
Published: November 2008

We use data from the Finnish polytechnic reform to distinguish between human capital and signalling theories of the value of education. We find that the reform increased the earnings of polytechnic graduates compared with those graduating from the same schools before the reform, as predicted by both the human capital and the signalling models. However, we also find that the relative earnings of vocational college graduates decrease after polytechnic graduates start entering the labour market. This finding is inconsistent with the pure human capital model and can be interpreted as evidence that supports the signalling model.
Education and Fertility: Evidence from a Natural Experiment*
Authors: Monstad Karin , Propper Carol , Salvanes Kjell G.
Published: November 2008

Declining fertility is often attributed to the increased education of women. It is difficult to establish a causal link because both fertility and education have changed secularly. In this paper we study the connection between fertility and education using educational reform as an instrument to control for selection. Our results indicate that increasing education leads to postponement of first births away from teenage motherhood and towards women having their first birth in their 20s as well as, for a smaller group, up to the age of 35–40. We find no evidence, however, that more education results in more women remaining childless or having fewer children.
Domestic Violence and the Exemption from Seeking Child Support: Providing Safety or Legitimizing Ongoing Poverty and Fear
Authors: Patrick Rebecca , Cook Kay , McKenzie Hayley
Published: November 2008

This article examines the experience of low‐income women on welfare in Australia and the process of seeking child support from a violent ex‐partner, contrasting this with research from the United States and the United Kingdom. Women in Australia who fear ongoing or renewed abuse as a result of seeking child support are eligible for an exemption. However, the exemption policy does not necessarily provide the intended protection of women and children from ongoing abuse and poverty. The exemption policy route also produces an unintended outcome whereby the perpetrators of violence are financially rewarded as they do not have to pay child support. These outcomes are shaped by a complex interaction of personal, cultural and structural forces that make the process of seeking child support for women who have experienced violence extremely problematic. The article demonstrates how in Australia, as in the US and UK policy contexts, the needs of women and their children are compromised by the details of policy specification and the way policies are implemented within the different systems.
Informing Debate or Fuelling Dispute? Media Communication of Reconfiguration in Scotland's Rural Maternity Care
Authors: Thomson Elizabeth , Farmer Jane , Tucker Janet , Bryers Helen
Published: November 2008

Public reaction to the UK's ongoing health sector reform often results in dilution of policy‐makers’ goals. Public participation in health service decision‐making is advocated in policy, but precisely how to do it and what role public opinion should have in formulating reform strategy is ambiguously described. Public opinion is formed through many influences, including media reporting. This paper examines how reconfiguration at a rural maternity unit at Caithness General Hospital in Wick, Scotland, was communicated in national and local media and considers potential implications of media communication on public participation in policy decision‐making. Content analysis of arguments for and against change revealed a high level of reporting of commentators against change in regional newspapers. Qualitative analysis identified emergent themes about how maternity service reconfiguration was portrayed. These included framing opposition between management and local people, and change drivers receiving superficial coverage. Findings suggest that media portrayal of the public role in change may promote an adversarial rather than a participative stance. More finely tuned understanding of the relationship between the reporting of change and public reaction should be attained as this could affect how planned social policy evolves into actual practice.