bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling the long-term dynamics of pre-vaccination pertussis
Authors: Rozhnova Ganna , Nunes Ana
Published: June 2012

The dynamics of strongly immunizing childhood infections is still not well understood. Although reports of successful modelling of several data records can be found in the previous literature, the key determinants of the observed temporal patterns have not yet been clearly identified. In particular, different models of immunity waning and degree of protection applied to disease- and vaccine-induced immunity have been debated in the previous literature on pertussis. Here, we study the effect of disease-acquired immunity on the long-term patterns of pertussis prevalence. We compare five minimal models, all of which are stochastic, seasonally forced, well-mixed models of infection, based on susceptible–infective–recovered dynamics in a closed population. These models reflect different assumptions about the immune response of naive hosts, namely total permanent immunity, immunity waning, immunity waning together with immunity boosting, reinfection of recovered and repeat infection after partial immunity waning. The power spectra of the output prevalence time series characterize the long-term dynamics of the models. For epidemiological parameters consistent with published data, the power spectra show quantitative and even qualitative differences, which can be used to test their assumptions by comparison with ensembles of several-decades-long pre-vaccination data records. We illustrate this strategy on two publicly available historical datasets.
The insectivorous batPipistrellus nathusiiuses a mixed-fuel strategy to power autumn migration
Authors: Voigt Christian C. , Sörgel Karin , Šuba Jurģis , Keišs Oskars , Pētersons Gunārs
Published: June 2012

In contrast to birds, bats are possibly limited in their capacity to use body fat as an energy source for long migrations. Here, we studied the fuel choice of migratoryPipistrellus nathusii(approximate weight: 8 g) by analysing the stable carbon isotope ratio (δ13CV-PDB) of breath and potential energy sources. Breathδ13CV-PDBwas intermediate betweenδ13CV-PDBof insect prey and adipocyte triacylglycerols, suggesting a mixed-fuel use ofP. nathusiiduring autumn migration. To clarify the origin of oxidized fatty acids, we performed feeding experiments with captiveP. nathusii. After an insect diet, bat breath was enriched in13C relative to the bulk and fat portion of insects, but not deviating from the non-fat portion of insects, suggesting that bats oxidized exogenous proteins and carbohydrates, but not exogenous fatty acids. A feeding experiment with13C-labelled substrates confirmed these findings. In conclusion, migratoryP. nathusiioxidized dietary proteins directly from insects captured en route in combination with endogenous fatty acids from adipocytes, and replenished their body reserves by routing dietary fatty acids to their body reserves.
Rapid antagonistic coevolution between strains of the social amoeba
Dictyostelium discoideum
Authors: Hollis Brian
Published: June 2012

Social groups face a fundamental problem of overcoming selfish individuals capable of destroying cooperation. In the social amoeba
Dictyostelium discoideum
, there is evidence that some clones (‘cheaters’) contribute disproportionately to the viable spores in a fruiting body while avoiding the dead stalk cell fate. It remains unclear, however, whether this cheating is actually the product of selection. Here, I report the results of an experimental evolution study designed to test whether clones of
D. discoideum
will evolve resistance to cheating in the laboratory with genetic variation created only through spontaneous mutation. Two strains, one green fluorescent protein (GFP)-labelled and one wild-type, were allowed to grow and develop together before the wild-type strain was removed and replaced with a naïve strain evolving in parallel. Over the course of 10 social generations, the GFP-labelled strain reliably increased its representation in the spores relative to control populations that had never experienced the competitor. This competitive advantage extended to the non-social, vegetative growth portion of the life cycle, but not to pairwise competition with two other strains. These results indicate strong antagonism between strains, mediated by ample mutational variation for cheating and also suggest that arms races between strains in the wild may be common.
Does morphological convergence imply functional similarity? A test using the evolution of quadrupedalism in ornithischian dinosaurs
Authors: Maidment Susannah C. R. , Barrett Paul M.
Published: June 2012

Convergent morphologies are thought to indicate functional similarity, arising because of a limited number of evolutionary or developmental pathways. Extant taxa displaying convergent morphologies are used as analogues to assess function in extinct taxa with similar characteristics. However, functional studies of extant taxa have shown that functional similarity can arise from differing morphologies, calling into question the paradigm that form and function are closely related. We test the hypothesis that convergent skeletal morphology indicates functional similarity in the fossil record using ornithischian dinosaurs. The rare transition from bipedality to quadrupedality occurred at least three times independently in this clade, resulting in a suite of convergent osteological characteristics. We use homology rather than analogy to provide an independent line of evidence about function, reconstructing soft tissues using the extant phylogenetic bracket and applying biomechanical concepts to produce qualitative assessments of muscle leverage. We also optimize character changes to investigate the sequence of character acquisition. Different lineages of quadrupedal ornithischian dinosaur stood and walked differently from each other, falsifying the hypothesis that osteological convergence indicates functional similarity. The acquisition of features correlated with quadrupedalism generally occurs in the same order in each clade, suggesting underlying developmental mechanisms that act as evolutionary constraints.
Line–Line Fault Analysis and Protection Challenges in Solar Photovoltaic Arrays
Authors: Zhao Ye , De Palma Jean-Francois , Mosesian Jerry , Lyons Robert , Lehman Brad
Published: June 2012

Fault analysis in solar photovoltaic (PV) arrays is a fundamental task to protect PV modules from damage and to eliminate risks of safety hazards. This paper focuses on line-line faults in PV arrays that may be caused by short-circuit faults or double ground faults. The effect on fault current from a maximum-power-point tracking of a PV inverter is discussed and shown to, at times, prevent overcurrent protection devices (OCPDs) to operate properly. Furthermore, fault behavior of PV arrays is highly related to the fault location, fault impedance, irradiance level, and use of blocking diodes. Particularly, this paper examines the challenges to OCPD in a PV array brought by unique faults: One is a fault that occurs under low-irradiance conditions, and the other is a fault that occurs at night and evolves during “night-to-day” transition. In both circumstances, the faults might remain hidden in the PV system, no matter how irradiance changes afterward. These unique faults may subsequently lead to unexpected safety hazards, reduced system efficiency, and reduced reliability. A small-scale experimental PV system has been developed to further validate the conclusions.
Lipid rafts, microdomain heterogeneity and inter‐organelle contacts: Impacts on membrane preparation for proteomic studies
Authors: Minogue Shane , Waugh Mark G.
Published: June 2012

In recent years, there has been considerable interest in mapping the protein content of isolated organelles using mass spectrometry. However, many subcellular compartments are highly dynamic with diverse and intricate architectures that are not always preserved during membrane isolation procedures. Furthermore, lateral heterogeneities in intra‐membrane lipid and protein concentrations underlie the formation of membrane microdomains, trafficking vesicles and inter‐membrane contacts. These complexities in membrane organisation have important consequences for the design of membrane preparation strategies and test the very concept of organelle purity. We illustrate how some of these biological considerations are relevant to membrane preparation and assess the numerous potential pitfalls in attempting to purify organelles from mammalian cells.
JAK2‐related pathway induces acquired erlotinib resistance in lung cancer cells harboring an epidermal growth factor receptor‐activating mutation
Authors: Harada Daijiro , Takigawa Nagio , Ochi Nobuaki , Ninomiya Takashi , Yasugi Masayuki , Kubo Toshio , Takeda Hiromasa , Ichihara Eiki , Ohashi Kadoaki , Takata Saburo , Tanimoto Mitsune , Kiura Katsuyuki
Published: June 2012

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors, such as gefitinib and erlotinib, are effective for non‐small cell lung cancer with activating EGFR mutations. However, even in patients with an initial dramatic response to such a drug, acquired resistance develops after 6–12 months. A secondary mutation of T790M in EGFR and amplification of the MET gene account for this resistance; however, the mechanism(s) of approximately 30% of acquired resistance cases remain unknown. We established an erlotinib‐resistant lung cancer cell line named PC‐9/ER3 that harbors an EGFR mutation after continuously exposing PC‐9 cells to erlotinib. PC‐9/ER3 cells were 136‐fold more resistant to erlotinib than the parental cells. Although the PC‐9/ER3 cells did not carry the T790M mutation or MET amplification and had similar levels of phosphorylated (p) STAT3, pJAK2 increased in the resistant cells. It was found in the present study that 3–12 h of exposure to erlotinib in both cell lines did not affect pJAK2 expression, but did result in increased pSTAT3 expression. pAkt in PC‐9/ER3 cells was less suppressed than in PC‐9 cells, although pEGFR and pMAPK were markedly suppressed in both cell lines. The combined treatment of erlotinib plus a JAK2 inhibitor (JSI‐124) suppressed pAkt in PC‐9/ER3 cells. Similarly, the combination of erlotinib plus JSI‐124 or siRNA against JAK2 restored sensitivity to erlotinib in PC‐9/ER3 cells. The combination of erlotinib plus JSI‐124 was also effective for reducing PC‐9/ER3 tumors in a murine xenograft model. Our results suggest that the activation of JAK2 partially accounts for acquired erlotinib resistance.(Cancer Sci, doi: 10.1111/j.1349‐7006.2012.02363.x, 2012)
An international legal strategy for alcohol control: not a framework convention—at least not yet
Authors: Taylor Allyn L. , Dhillon Ibadat S.
Published: June 2012

Aims  The perceived success of the Framework Convention on Tobacco Control (FCTC) in influencing national and global public health policies has led to growing interest in promulgating new international legal instruments to address global health issues—including calls for a Framework Convention on Alcohol Control (FCAC).

Methods  Despite broad support in the public health community, the authors caution that an analysis of the value of lawmaking for alcohol control cannot rest solely on the character of the underlying public health challenge and the similarities between alcohol control and tobacco control. Other factors must be considered, including the relative political feasibility for global health lawmaking. The potential contribution of non‐binding international legal instruments to advancing global alcohol control, in particular, deserves strong consideration.

Results  The authors propose a gradual international legal strategy for alcohol control, starting with a non‐binding code of practice focusing on areas of critical concern with wide political consensus, leading over time to a comprehensive binding treaty. Although often dismissed as ineffective relative to treaties, non‐binding international legal instruments have particular strengths and can create both norms and processes that impact the behavior of states and other actors, overcoming a number of limitations of more rigid legally binding strategies.

Conclusions  Ultimately, the authors contend that the negotiation and adoption of a non‐binding international legal instrument as a first step in a long‐run legal strategy offers a more politically realistic, and potentially superior, alternative to immediate efforts to achieve a Framework Convention on Alcohol Control.
Leucocytosis in women with polycystic ovary syndrome (PCOS) is incompletely explained by obesity and insulin resistance
Authors: Phelan N. , O'Connor A. , Kyaw Tun T. , Correia N. , Boran G. , Roche H. M. , Gibney J.
Published: June 2012

Objectives

Low‐grade chronic inflammation predicts cardiovascular outcomes and is observed in women with polycystic ovary syndrome (PCOS). Whether this is entirely a cause or consequence of insulin resistance (IR) is unknown.

Methods

Seventy pairs of women with and without PCOS, matched for age, body mass index (BMI) and IR (HOMA, QUICKI and Avignon index), were generated from a larger cohort of 103 women with and 104 BMI‐matched women without PCOS. Women with PCOS were studied in the follicular phase of the menstrual cycle. White cell count (WCC), high‐sensitivity CRP (hsCRP) and a series of 12 cytokines and growth factors were measured. These inflammatory markers were also compared between women with PCOS and 10 normal women studied in the follicular, peri‐ovulatory and luteal stages.

Results

When all subjects were compared, WCC (6·75 × 109 vs 5·60 × 109 g/l, P < 0·005), hsCRP (4·04 vs 2·90 mg/l, P < 0·05) and IL‐6 (1·11 vs 0·72 pg/ml, P < 0·05) were greater in women with PCOS. Pair‐matching for IR eliminated between‐group differences in hsCRP and cytokines but did not alter the difference in WCC (6·60 × 109 vs 5·60 × 109 g/l, P < 0·005). WCC was greater in PCOS compared to normal women at all stages of the menstrual cycle.

Conclusions

Low‐grade inflammation occurs in PCOS. Increased hsCRP and cytokines are associated with IR, but increased WCC is observed even when IR is accounted for. The explanation for this and its clinical significance is unknown.
Very‐long‐chain fatty acids have an essential role in plastid division by controlling Z‐ring formation in Arabidopsis thaliana
Authors: Nobusawa Takashi , Umeda Masaaki
Published: June 2012

Recent studies have showed the essential mechanisms for plastid division that have bacterial orthologues, such as
FtsZ
and Min system proteins; however, causal factors regulating plastid division in plant cells are poorly understood. Here, we show that plastid division is inhibited in
Arabidopsis by reduced amounts of very‐long‐chain fatty acids (VLCFAs), which have an acyl chain length of more than 20 carbons and are used for cuticular wax formation. The number of amyloplasts and chloroplasts decreased in the mutant defective in VLCFA synthesis and in wild‐type plants treated with an inhibitor of VLCFA synthesis. Although similar inhibition of plastid division was observed in transgenic plants that over‐expressed
PDV2
, one of the outer membrane proteins at the plastid division site, dot‐like aggregates of
FtsZ
protein and disordered placement of multiple Z‐rings were found in wild‐type chloroplasts treated the inhibitor of VLCFA synthesis. Expression analysis showed that
ARC3
, one of the Min system genes, was down‐regulated under low VLCFA conditions. Our results indicate that VLCFAs or VLCFA‐containing lipids have an essential role in plastid division by controlling Z‐ring formation, showing a novel function of plant VLCFAs.
Cannabinoid Modulation of Midbrain Urocortin 1 Neurones During Acute and Chronic Stress
Authors: Derks N. M. , Pintér O. , Zuure W. , Ledent C. , Watanabe M. , Molnár C. S. , Wei Y. , Roubos E. W. , Wu S. , Hrabovszky E. , Zelena D. , Kozicz T.
Published: June 2012

Neurones in the centrally projecting Edinger–Westphal nucleus (EWcp) are the main site of urocortin 1 (Ucn1) synthesis in the mammalian brain, and are assumed to play a role in the stress response of the animal. Because endocannabinoid signalling has also been strongly implicated in stress, we hypothesised that endocannabinoids may modulate the functioning of the urocortinergic EWcp. First, using in situ hybridisation, we demonstrated cannabinoid receptor 1 (CB1R) mRNA expression in mouse EWcp‐neurones that were Ucn1‐negative. Dual‐ and triple‐label immunocytochemistry revealed the presence of CB1R in several GABA‐immunopositive fibres juxtaposed to EWcp‐Ucn1 neurones. To test functional aspects of such an anatomical constellation, we compared acute (1 h of restraint) and chronic (14 days of chronic mild stress) stress‐induced changes in wild‐type (WT) and CB1R knockout (CB1R‐KO) mice. Acute and especially chronic stress resulted in an increase in Ucn1 content of the EWcp, which was attenuated in CB1R‐KO mice. CB1R‐KO mice had higher basal and chronic stress‐induced adrenocorticotrophin and corticosterone levels and were more anxious on the elevated plus‐maze versus WT. Collectively, our results show for the first time EWcp‐Ucn1 neurones are putatively innervated by endocannabinoid sensitive, inhibitory, GABAergic afferents. In addition, we provide novel evidence that the absence of the CB1 receptor alters the Ucn1 mRNA and peptide levels in EWcp neurones, concomitant with an augmented stress response and increased anxiety‐like behaviour.
Daytime continuous polysomnography predicts MSLT results in hypersomnias of central origin
Authors: PIZZA FABIO , MOGHADAM KEIVAN K. , VANDI STEFANO , DETTO STEFANIA , POLI FRANCESCA , MIGNOT EMMANUEL , FERRI RAFFAELE , PLAZZI GIUSEPPE
Published: June 2012

In the diagnostic work‐up of hypersomnias of central origin, the complaint of excessive daytime sleepiness should be objectively confirmed by MSLT findings. Indeed, the features and diagnostic utility of spontaneous daytime sleep at 24 h continuous polysomnography (PSG) have never been investigated. We compared daytime PSG features to MSLT data in 98 consecutive patients presenting with excessive daytime sleepiness and with a final diagnosis of narcolepsy with cataplexy/hypocretin deficiency (n = 39), narcolepsy without cataplexy (n = 7), idiopathic hypersomnia without long sleep time (n = 19), and ‘hypersomnia’ with normal sleep latency at MSLT (n = 33). Daytime sleep time was significantly higher in narcolepsy‐cataplexy but similar in the other groups. Receiver operating characteristics (ROC) curves showed that the number of naps during daytime PSG predicted a mean sleep latency ≤8 min at MSLT with an area under the curve of 0.67 ± 0.05 (P = 0.005). The number of daytime sleep‐onset REM periods (SOREMPs) in spontaneous naps strikingly predicted the scheduled occurrence of two or more SOREMPs at MSLT, with an area under the ROC curve of 0.93 ± 0.03 (P < 10−12). One spontaneous SOREMP during daytime had a sensitivity of 96% with specificity of 74%, whereas two SOREMPs had a sensitivity of 75%, with a specificity of 95% for a pathological REM sleep propensity at MSLT. The features of spontaneous daytime sleep well correlated with MSLT findings. Notably, the occurrence of multiple spontaneous SOREMPs during daytime clearly identified patients with narcolepsy, as well as during the MSLT.
Precocious egg development in the blowfly Calliphora vicina: implications for developmental studies and post‐mortem interval estimation
Authors: DAVIES K. , HARVEY M.
Published: June 2012

The occurrence of precocious egg development in forensically important calliphorid species has previously been reported; however, the frequency of occurrence in both wild and captive colonies, and the consequent effects on developmental studies and post‐mortem interval (PMI) estimates, are largely unknown. A PMI estimate based on samples developed from precocious eggs could be extended by the entire period of embryogenesis, which at 22 °C would result in a significant error of around 24 h. This study examined the occurrence of precocious egg development in Calliphora vicina Robineau‐Desvoidy (Diptera: Calliphoridae) wild‐caught and captive‐bred adults by investigating the presence of larvae in the adult female genital chamber and by monitoring hatching times of entire batches of eggs throughout embryogenesis, respectively. A total of 8.82% of gravid wild‐caught females contained a larva in the genital tract (i.e. a precocious egg). This indicates that all specimens collected should be considered potentially precocious for the purpose of PMI estimation. Less than 2.55% of a batch of eggs laid by captive females were precocious; protocols for minimizing the effect of precocious eggs on developmental studies are suggested.
The magnetosome membrane protein, MmsF, is a major regulator of magnetite biomineralization in Magnetospirillum magneticum AMB‐1
Authors: Murat Dorothée , Falahati Veesta , Bertinetti Luca , Csencsits Roseann , Körnig André , Downing Kenneth , Faivre Damien , Komeili Arash
Published: June 2012

Magnetotactic bacteria (MTB) use magnetosomes, membrane‐bound crystals of magnetite or greigite, for navigation along geomagnetic fields. In Magnetospirillum magneticum sp. AMB‐1, and other MTB, a magnetosome gene island (MAI) is essential for every step of magnetosome formation. An 8‐gene region of the MAI encodes several factors implicated in control of crystal size and morphology in previous genetic and proteomic studies. We show that these factors play a minor role in magnetite biomineralization in vivo. In contrast, MmsF, a previously uncharacterized magnetosome membrane protein encoded within the same region plays a dominant role in defining crystal size and morphology and is sufficient for restoring magnetite synthesis in the absence of the other major biomineralization candidates. In addition, we show that the 18 genes of the mamAB gene cluster of the MAI are sufficient for the formation of an immature magnetosome organelle. Addition of MmsF to these 18 genes leads to a significant enhancement of magnetite biomineralization and an increase in the cellular magnetic response. These results define a new biomineralization protein and lay down the foundation for the design of autonomous gene cassettes for the transfer of the magnetic phenotype in other bacteria.
A conformational switch controls cell wall‐remodelling enzymes required for bacterial cell division
Authors: Yang Desirée C. , Tan Kemin , Joachimiak Andrzej , Bernhardt Thomas G.
Published: June 2012

Remodelling of the peptidoglycan (PG) exoskeleton is intimately tied to the growth and division of bacteria. Enzymes that hydrolyse PG are critical for these processes, but their activities must be tightly regulated to prevent the generation of lethal breaches in the PG matrix. Despite their importance, the mechanisms regulating PG hydrolase activity have remained elusive. Here we investigate the control of cell division hydrolases called amidases (AmiA, AmiB and AmiC) required for Escherichia coli cell division. Poorly regulated amiB mutants were isolated encoding lytic AmiB variants with elevated basal PG hydrolase activities in vitro. The structure of an AmiB orthologue was also solved, revealing that the active site of AmiB is occluded by a conserved alpha helix. Strikingly, most of the amino acid substitutions in the lytic AmiB variants mapped to this domain and are predicted to disrupt its interaction with the active site. Our results therefore support a model in which cell separation is stimulated by the reversible relief of amidase autoinhibition governed by conserved subcomplexes within the cytokinetic ring. Analogous conformational control mechanisms are likely to be part of a general strategy used to control PG hydrolases present within multienzyme PG‐remodelling machines.
Refining the criterion for an abnormal Integrated Relaxation Pressure in esophageal pressure topography based on the pattern of esophageal contractility using a classification and regression tree model
Authors: Lin Z. , Kahrilas P. J. , Roman S. , Boris L. , Carlson D. , Pandolfino J. E.
Published: June 2012

Background  The Integrated Relaxation Pressure (IRP) is the esophageal pressure topography (EPT) metric used for assessing the adequacy of esophagogastric junction (EGJ) relaxation in the Chicago Classification of motility disorders. However, because the IRP value is also influenced by distal esophageal contractility, we hypothesized that its normal limits should vary with different patterns of contractility.

Methods  Five hundred and twenty two selected EPT studies were used to compare the accuracy of alternative analysis paradigms to that of a motility expert (the ‘gold standard’). Chicago Classification metrics were scored manually and used as inputs for MATLAB™ programs that utilized either strict algorithm‐based interpretation (fixed abnormal IRP threshold of 15 mmHg) or a classification and regression tree (CART) model that selected variable IRP thresholds depending on the associated esophageal contractility.

Key Results  The sensitivity of the CART model for achalasia (93%) was better than that of the algorithm‐based approach (85%) on account of using variable IRP thresholds that ranged from a low value of >10 mmHg to distinguish type I achalasia from absent peristalsis to a high value of >17 mmHg to distinguish type III achalasia from distal esophageal spasm. Additionally, type II achalasia was diagnosed solely by panesophageal pressurization without the IRP entering the algorithm.

Conclusions & Inferences  Automated interpretation of EPT studies more closely mimics that of a motility expert when IRP thresholds for impaired EGJ relaxation are adjusted depending on the pattern of associated esophageal contractility. The range of IRP cutoffs suggested by the CART model ranged from 10 to 17 mmHg.
Comparison of small‐bowel motility of the human jejunum and ileum
Authors: Seidl H. , Gundling F. , Pfeiffer A. , Pehl C. , Schepp W. , Schmidt T.
Published: June 2012

Background  Knowledge about human cyclic fasting motility (MMC) and the postprandial response is mostly based on manometric findings in the upper small intestine. Hardly any data exist on human ileal motility, as the acquisition of data has been limited by methodological concerns.

The aim was to study human jejunal and ileal motility in an optimized manometric setting.

Methods  Solid‐state 24‐h‐manometry was performed in the jejunum and ileum of healthy individuals, applying a strict protocol for fasting, resting, and the consumption of a standardized meal. Both visual qualitative and validated computerized quantitative contraction and propagation analysis were performed.

Key Results  MMC occurs in similar frequency in the jejunum and ileum, but it was significantly shorter in the jejunum at night. By many characteristics, ileal motility was less intense and propagative than jejunal: less migrating clustered contractions, and slower propagation velocity and shorter distance in phases II and III, and postprandially – possibly slowing and enhancing nutrient absorption. Prolonged propagated contractions in some individuals were identified as a unique ileal propulsive pattern. Postprandially, an abrupt conversion to a digestive motility pattern occurs simultaneously independent of the region.

Conclusions & Inferences  We found similar basic phenomena of fasting and postprandial motility in the jejunum and ileum of healthy humans. However, different calibration of propagative and contractile activity and special motor events in the ileum may account for a different physiological role in digestion. Future studies of small‐bowel motility in healthy and diseased subjects focusing on segmental differences of proximal and distal intestine may be rewarded.
Unique roles of Schistosoma japonicum protein Sj16 to induce IFN‐γ and IL‐10 producing CD4+CD25+ regulatory T cells in vitro and in vivo
Authors: SUN X. J. , LI R. , SUN X. , ZHOU Y. , WANG Y. , LIU X. J. , LU Q. , ZHOU C. L. , WU Z. D.
Published: June 2012

Various proteins are expressed during different stages of schistosome development that are essential for cercarial penetration of vertebrate skin and evasion of host immune response. CD4+CD25+ regulatory T cells are important in modulating immune responses towards helminth infections. Schistosoma japonicum protein Sj16 present in the secretions of schistosomula has been shown to have anti‐inflammatory effects; however, it is uncertain whether Sj16 can induce CD4+CD25+ regulatory T cells to participate in the regulation of early infection. In this study, we demonstrate a relationship between recombinant Sj16 (rSj16) and the induction of CD4+CD25+ Foxp3+ regulatory T cells. An increase in CD4+CD25+ T cells was observed both in splenic cells from mice injected with rSj16 and the cells pretreated with rSj16, respectively. The induced CD4+CD25+ T cells suppressed CD4+CD25− T‐cell proliferation; furthermore, IFN‐γ and IL‐10 released from rSj16‐stimulated cells contribute to this suppression. Additionally, rSj16‐treated bone marrow dendritic cells (BMDCs) demonstrate an immature phenotype and play a role in the conversion of CD4+CD25− T cells into suppressive CD4+CD25+ regulatory T cells. Our study identified a new CD4+CD25+ T‐cell population that induced by rSj16 and suggests that an IFN‐γ‐biased microenvironment during early infection of schistosome may favour the establishment of infection.
Discovery of a multigene family of aquaporin silicon transporters in the primitive plant Equisetum arvense
Authors: Grégoire Caroline , Rémus‐Borel Wilfried , Vivancos Julien , Labbé Caroline , Belzile François , Bélanger Richard R.
Published: June 2012

Plants benefit greatly from silicon (Si) absorption provided that they contain Si transporters. The latter have recently been identified in the roots of some higher plants known to accumulate high concentrations of Si, and all share a high level of sequence identity. In this study, we searched for transporters in the primitive vascular plant Equisetum arvense (horsetail), which is a valuable but neglected model plant for the study of Si absorption, as it has one of the highest Si concentrations in the plant kingdom. Our initial attempts to identify Si transporters based on sequence homology with transporters from higher plants proved unsuccessful, suggesting a divergent structure or property in horsetail transporters. Subsequently, through sequencing of the horsetail root transcriptome and a search using amino acid sequences conserved in plant aquaporins, we were able to identify a multigene family of aquaporin Si transporters. Comparison of known functional domains and phylogenetic analysis of sequences revealed that the horsetail proteins belong to a different group than higher‐plant Si transporters. In particular, the newly identified proteins contain a STAR pore as opposed to the GSGR pore common to all previously identified Si transporters. In order to determine its functionality, the proteins were heterologously expressed in both Xenopus oocytes and Arabidopsis, and the results showed that the horsetail proteins are extremely efficient a transporting Si. These findings offer new insights into the elusive properties of Si and its absorption by plants.
The Snf1‐related protein kinases SnRK2.4 and SnRK2.10 are involved in maintenance of root system architecture during salt stress
Authors: McLoughlin Fionn , Galvan‐Ampudia Carlos S. , Julkowska Magdalena M. , Caarls Lotte , van der Does Dieuwertje , Laurière Christiane , Munnik Teun , Haring Michel A. , Testerink Christa
Published: June 2012

The sucrose non‐fermenting‐1‐related protein kinase 2 (SnRK2) family represents a unique family of plant‐specific protein kinases implicated in cellular signalling in response to osmotic stress. In our studies, we observed that two class 1 SnRK2 kinases, SnRK2.4 and SnRK2.10, are rapidly and transiently activated in Arabidopsis roots after exposure to salt. Under saline conditions, snrk2.4 knockout mutants had a reduced primary root length, while snrk2.10 mutants exhibited a reduction in the number of lateral roots. The reduced lateral root density was found to be a combinatory effect of a decrease in the number of lateral root primordia and an increase in the number of arrested lateral root primordia. The phenotypes were in agreement with the observed expression patterns of genomic yellow fluorescent protein (YFP) fusions of SnRK2.10 and ‐2.4, under control of their native promoter sequences. SnRK2.10 was found to be expressed in the vascular tissue at the base of a developing lateral root, whereas SnRK2.4 was expressed throughout the root, with higher expression in the vascular system. Salt stress triggered a rapid re‐localization of SnRK2.4–YFP from the cytosol to punctate structures in root epidermal cells. Differential centrifugation experiments of isolated Arabidopsis root proteins confirmed recruitment of endogenous SnRK2.4/2.10 to membranes upon exposure to salt, supporting their observed binding affinity for the phospholipid phosphatidic acid. Together, our results reveal a role for SnRK2.4 and ‐2.10 in root growth and architecture in saline conditions.
Outcome in polytraumatized patients with and without brain injury
Authors: GROSS T. , SCHÜEPP M. , ATTENBERGER C. , PARGGER H. , AMSLER F.
Published: June 2012

Background

To investigate the long‐term outcome in polytrauma victims with traumatic brain injury (TBI) and without traumatic brain injury (NTBI).

Methods

Cohort study based on prospectively collected data. Evaluation of functional outcome and quality of life at least 2 years (median 2.5) following trauma in 111 survivors [39.5 ± 20.9 years; injury severity score (ISS) 27.9 ± 8.2; TBI: n = 45; NTBI: n = 66] out of a total of 211 consecutive multiply‐injured patients with an ISS > 16, all primarily admitted to the intensive care unit.

Results

Significantly fewer TBI patients lived independently compared with NTBI patients (71% vs. 95%; P < 0.001). TBI patients showed a higher decrease in their capacity to work compared with NTBI patients (P < 0.002). Both study groups experienced a significantly reduced long‐term outcome in comparison with pre‐injury level in all dimensions of the short form (SF)‐36. Following stepwise logistic regression, the mental sum component of the SF‐36 and the Nottingham Health Profile discriminated independently between TBI and NTBI patients (R
2 = 0.219; P < 0.001).

Conclusion

More than 2 years after injury, polytraumatized patients with and without TBI suffer from a reduction in functional outcome and quality of life, but TBI patients are doing importantly worse. Any comparison of trauma patient cohorts should consider these differences between TBI and NTBI patients. Given their discriminatory potential, the sensitivity of self‐reported measures needs further affirmation with neuropsychological assessments.
Vigilance Decreases with Time at Loafing Sites in Gulls (Larus spp.)
Authors: Beauchamp Guy , Ruxton Graeme D.
Published: June 2012

Understanding how animals partition effort between vigilance for predators and other conflicting activities has been a mainstay of animal behaviour research. Classical theories implicitly assume that animals alternate between high and low vigilance states over short timescales, but that average effort invested in vigilance is constant over an extended bout of such alternations. However, one recent model suggests that vigilance should be adjusted dynamically to short‐term changes in the perception of predation risk and would tend to decrease with time. Indeed, as time passes by without disturbances, perception of the need for vigilance should decrease and prey animals may allocate more time to competing activities. Here, we examined how the proportion of sleeping gulls (Larus spp.) in loafing groups changed over time. Sleeping gulls can only maintain low levels of vigilance against external threats (compared to alert individuals), and we predicted that the proportion of sleeping gulls at loafing sites should increase over time when no disturbances occur. Statistically significant changes in the proportion of sleeping gulls as a function of time occurred in the majority of sequences and an increase was observed significantly more often than predicted by chance alone. This temporal pattern cannot be caused by reduction in hunger levels because gulls are not feeding at loafing sites. The results indicate that vigilance can be adjusted dynamically in response to short‐term temporal changes in the perception of predation risk.
Chronological vs. Physiological Age as Determinants of Mating Decisions: Studies on Female Choice Over Lifespan in An Acoustic Moth
Authors: Ligout Séverine , Munier Damien , Marquereau Lucie , Greenfield Michael D.
Published: June 2012

Life history theory predicts that females may adjust the selectivity expressed in mate choice as they age. Particularly in cases where time is limiting, females are expected to reduce selectivity and thereby avoid losing a terminal mating opportunity. Some evidence for this reduction has been found in vertebrates and long‐lived insects, and several recent findings show that it may also exist in insects with very short adult longevities. Theory also predicts that behavioural adjustments should respond to remaining longevity (physiological age) rather than chronological age, but very little information relevant to this issue exists. We studied age‐related changes in mating behaviour in an acoustic moth species (Achroia grisella; Lepidoptera: Pyralidae) in which females choose males based on the intensity, rhythm and other temporal features of the male song, with the objective of determining whether observed adjustments reflect chronological or physiological age. In accordance with theory, we found that females became less selective in their evaluation of male song rhythm as they aged and that this adjustment was predicted by physiological rather than chronological age. The reduction in selectivity may be due to decreased movement and searching, factors that can prevent a female from perceiving all of the male songs being broadcast locally in a complex environment where the transmission of some songs is blocked in some locations. We did not observe these age‐related effects in a simpler, open environment.
Gas Exchange of Five Warm‐Season Grain Legumes and their Susceptibility to Heat Stress
Authors: Herzog H. , Chai‐Arree W.
Published: June 2012

Objective of this study was to compare the heat stress performance of four pulses from dry and hot areas (mungbeans, limabeans, and teparybeans and cowpeas) with that of soybeans. Two experiments were conducted in growth chambers, and data were pooled because results of both experiments were similar. Plants were raised up to flowering at 24/17 °C (day/night) and were then either exposed to these temperatures until maturity or stressed with 33/24 °C for 2 weeks starting at day 1 or 15 after onset of flowering (early vs. late stress). Before, during and after these stress intervals, gas exchange of representative upper leaves was examined; additionally, immediate effects of increasing leaf temperatures from 24 to 32 or 40 °C on chlorophyll fluorescence were assessed. Without heat stress rates of photosynthesis (Pn), and of transpiration (TR), stomatal and mesophyll conductance (gs, gm) and intrinsic transpiration efficiency (iTE) differed significantly among the five crops at each date. However, because of crop‐specific time‐courses ranking among unstressed crops was instable with time, so values were integrated or averaged over time. This procedure revealed high Pn potentials in mung‐ and teparybeans and high iTE values in limabeans compared to the other crops. Heat stress lowered Pn and gs considerably, but increased TR in all five crops. Relative lowering of Pn during heat stress displayed a crop‐specific pattern with limabeans being least susceptible to both early and late heat stress, while cowpeas were highly susceptible to early stress. Effects on Pn were mainly attributable to lowering of gs and only in part to gm. The latter was supported by very small changes (<10 %) of various chlorophyll fluorescence signals shortly after raising leaf temperature to 32 °C in all species. However, in limabeans, a decreased electron transport rate (e‐rate, −18 %) and an increased non‐photochemical quenching (QN, +16 %) pointed to an adaptive mechanism to avoid oxidative strains under heat. Leaf temperatures of 40 °C immediately provoked stronger changes in all fluorescence signals than 32 °C; substantial damages at 40 °C were indicated by effective quantum yield, photochemical quenching and ratio of fluorescence decrease in mungbeans and low ones in cowpeas and soybeans. Nevertheless, some adaptive responses of e‐rates and QN were observed in all crops and were most expressed in limabeans.
Large‐scale development of microsatellite markers in Nicotiana tabacum and construction of a genetic map of flue‐cured tobacco
Authors: Tong Zhijun , Yang Zemao , Chen Xuejun , Jiao Fangchan , Li Xuying , Wu Xingfu , Gao Yulong , Xiao Bingguang , Wu Weiren
Published: June 2012

With 1 figure and 1 table

Molecular markers and genetic maps are useful tools for genetic research and molecular breeding. Although significant progress has been made recently on molecular marker development and genetic map construction in tobacco (Nicotiana tabacum), more efforts are still required to meet the needs of genetic research and breeding in this allotetraploid species. In this study, based on the expressed sequence tag (EST) data and genome sequence data of N. tabacum, we developed a total of 4886 simple sequence repeat (SSR) markers (including 1365 genomic SSRs and 3521 EST‐SSRs), which were functional in a set of eight tobacco varieties of four different types and were basically novel. Using these newly developed SSR markers as well as published SSR markers and a population of 207 double haploid (DH) lines derived from a cross between two flue‐cured tobacco varieties ‘Honghua Dajinyuan’ and ‘Hicks Broad Leaf’, we constructed a genetic map consisting of 611 SSR loci distributed on 24 tentative linkage groups and covering a total length of 1882.1 cM with an average distance of 3.1 cM between adjacent markers.
Expression of CYP26b1 and Related Retinoic Acid Signalling Molecules in Young, Peripubertal and Adult Dog Testis
Authors: Kasimanickam VR , Kasimanickam RK
Published: June 2012

Contents

The objective of the study was to elucidate mRNA expression of CYP26b1 (cytochrome P450, family 26, subfamily B, polypeptide 1) and signalling molecules ALDH1 (aldehyde dehydrogenase 1), CRABPII (cellular retinoic acid‐binding protein II), RARα (retinoic acid receptor alpha) and STRA8 (stimulated by retinoic acid gene 8) in dog testis from different post‐natal developmental ages. Testicular tissue samples were collected from medium‐sized mixed breed dogs at different ages such as young (<4 months; N = 4), peripubertal (4–8 months; N = 3) and adult (>8 months; N = 4) were used to evaluate relative mRNA expression. Genes of RA‐degrading enzyme CYP26b1, ALDH1 involved in RA synthesis and genes of carrier protein CRABPII involved in RA metabolism were turned on during the post‐natal testicular development in dogs. Their expression pattern differs at different developmental ages (p < 0.05), and the levels of mRNA expression were compensated towards a normal developmental response for the sexual maturity and continuous spermatogenesis. The mRNA expression of RARα, one of the RA receptors participates in RA signalling in connection to spermatogenesis, was recorded in young and adult stages at varying degree. STRA8 is one of the responsive genes with regard to meiosis, and this functional gene product was expressed in all ages with the changing level (p < 0.01). In summary, the expression pattern of RA signalling molecules differed from young to adult ages, and it is expected that these changes are to compensate towards a normal developmental response for the sexual maturity and continuous spermatogenesis.
Real‐time ultrasound guided placement of temporary internal jugular vein catheters: Assessment of technical success and complication rates in nephrology practice
Authors: AKOGLU HADIM , PISKINPASA SERHAN , YENIGUN EZGI C , OZTURK RAMAZAN , DEDE FATIH , ODABAS ALI R
Published: June 2012

Aim:  Internal jugular vein (IJV) catheterization is often required to gain access for haemodialysis. Use of ultrasound guidance has reduced the complication rates of this procedure. We hypothesized that nephrologists may perform IJV cannulation with a high technical success and low immediate complication rates under real‐time ultrasound guidance.

Methods:  We prospectively analyzed 323 patients (186 male, 137 female) who underwent IJV cannulation with real‐time ultrasound guidance. The number of needle punctures, technical success, the time between injection of local anaesthetic and entry into the IJV, and immediate complications were recorded. Patients with a history of multiple catheter insertions, previous difficulties during catheterization, poor compliance, obesity, impaired consciousness, skeletal deformity, disorder of haemostasis were regarded as high‐risk group.

Results:  Cannulation of IJV was achieved in all patients. Of the 323 catheters, 125 (38.7%) were placed in high‐risk patients. Average number of puncture was 1.26 (range, 1–4). IJV was entered on the first attempt in 261 (80.8%) patients. Only ten complications (10/323, 3.2%) developed; five (2.5%) in the normal‐risk group, and five (4.0%) in the high‐risk group. Cannulation of IJV took a longer time in the high‐risk group than in the normal‐risk group. The number of needle punctures, percent of successful cannulation on the first attempt, and the frequency of complications were similar between the high‐ and normal‐risk groups.

Conclusions:  Cannulation of IJV under real‐time ultrasound guidance is very safe with high technical success rates. Nephrologists can use this technique with ease and with minimal complications in normal‐ and high‐risk patients.
Caregiving experiences of families of persons with serious mental health problems in the Niger Delta region of Nigeria
Authors: Jack‐Ide Izibeloko O. , Uys Leana R. , Middleton Lyn E.
Published: June 2012

Mental health services are provided at Rumuigbo Hospital, a single facility that renders psychiatric services in Rivers State and surrounding states in the Niger Delta region of Nigeria. Psychiatric services are not provided at primary health‐care clinic or district hospitals, and access to this service can be problematic for many caregivers due to the time and costs involved. Therefore, this study explored the family caregiving experiences of persons with serious mental health problems in terms of the mental health‐care policy and health systems environment. A qualitative study using a purposive sampling technique was conducted among 20 caregivers attending a neuropsychiatric clinic in Port Harcourt, Rivers State, Nigeria. The results show that 78% of caregivers lived outside Port Harcourt and 65% had no regular monthly income. Stigma, poor knowledge in managing symptoms of ill relatives, financial implications, lack of support network, and absence of community outreach clinics were found to affect family caregiving experiences. Policies need to be developed and implemented that provide mental health care through primary health‐care services to ameliorate families' financial burden, enable early diagnosis and treatment, reduce the need to travel, and improve the quality of life of family caregivers.