bluuebunny/crossref_metadata_2025_split huggingface dataset:
Not going with the flow: a comprehensive time‐calibrated phylogeny of dragonflies (Anisoptera: Odonata: Insecta) provides evidence for the role of lentic habitats on diversification
Authors: Letsch Harald , Gottsberger Brigitte , Ware Jessica L. 
Published: February 2016

AbstractEcological diversification of aquatic insects has long been suspected to have been driven by differences in freshwater habitats, which can be classified into flowing (lotic) waters and standing (lentic) waters. The contrasting characteristics of lotic and lentic freshwater systems imply different ecological constraints on their inhabitants. The ephemeral and discontinuous character of most lentic water bodies may encourage dispersal by lentic species in turn reducing geographical isolation among populations. Hence, speciation probability would be lower in lentic species. Here, we assess the impact of habitat use on diversification patterns in dragonflies (Anisoptera: Odonata). Based on the eight nuclear and mitochondrial genes, we inferred species diversification with a model‐based evolutionary framework, to account for rate variation through time and among lineages and to estimate the impact of larval habitat on the potentially nonrandom diversification among anisopteran groups. Ancestral state reconstruction revealed lotic fresh water systems as their original primary habitat, while lentic waters have been colonized independently in Aeshnidae, Corduliidae and Libellulidae. Furthermore, our results indicate a positive correlation of speciation and lentic habitat colonization by dragonflies: speciation rates increased in lentic Aeshnidae and Libellulidae, whereas they remain mostly uniform among lotic groups. This contradicts the hypothesis of inherently lower speciation in lentic groups and suggests species with larger ranges are more likely to diversify, perhaps due to higher probability of larger areas being dissected by geographical barriers. Furthermore, larger range sizes may comprise more habitat types, which could also promote speciation by providing additional niches, allowing the coexistence of emerging species.
Persistent Vascular Remodeling and Leakiness are Important Components of the Pathobiology of Re‐bleeding in Hemophilic Joints: Two Informative Cases
Authors: Kidder Wesley , Chang Eric Y. , M. Moran Colleen , Rose Steven C. , von Drygalski Annette 
Published: February 2016

AbstractObjectiveIt is unclear if vascular remodeling in hemophilic joints perpetuates bleeding because it is difficult to gauge leakiness in the setting of low clotting factor levels. Two patients provided the unique opportunity to demonstrate that vascular changes directly contribute to joint bleeding.Approach and ResultsTwo patients had severe hemophilic arthropathies; joint vascularity and bleeding were studied during periods of normalized plasma clotting factor activities with MSKUS and PD. One patient was “cured” of hemophilia with liver transplantation. Abnormal elbow vascularization persisted despite normalization of coagulation status and was associated with severe bleeding years after transplant. Dynamic vascular changes were detected prior to and during bleeding; angiography revealed enlarged, thickened vessels consistent with remodeling, and required arterial embolization. The second patient had continued knee bleeding and fluctuating vascular changes for months following knee replacement, unresponsive to intense daily factor treatment. Subsequently, new bleeds developed in other joints associated with similar vascular changes despite continued factor replacement.ConclusionsVascular remodeling contributes to perpetuated hemophilic joint bleeding and therefore contributes to progressive arthropathy. Intra‐articular or systemic administration of anti‐angiogenic drugs, such as vascular endothelial growth factor antagonists, might be of benefit in such patients, but requires study.
The Representation of Agents in Auditory Verbal Hallucinations
Authors: Wilkinson Sam , Bell Vaughan 
Published: February 2016

AbstractCurrent models of auditory verbal hallucinations (AVHs) tend to focus on the mechanisms underlying their occurrence, but often fail to address the content of the auditory experience. In other words, they tend to ask why there are AVHs at all, instead of asking why, given that there are AVHs, they have the properties that they have. One such property, which has been largely overlooked and which we will focus on here, is why the voices are often experienced as coming from (or being the voices of) agents, and often specific, individualised agents. In this article, we argue not only that the representation of agents is important in accurately describing many cases of AVH, but also that deeper reflection on what is involved in the representation of agents has potentially vital consequences for our aetiological understanding of AVH, namely, for understanding how and why AVHs come about.
Streptomyces coelicolor XdhR is a direct target of (p)ppGpp that controls expression of genes encoding xanthine dehydrogenase to promote purine salvage
Authors: Sivapragasam Smitha , Grove Anne 
Published: February 2016

SummaryThe gene encoding Streptomyces coelicolor xanthine dehydrogenase regulator (XdhR) is divergently oriented from xdhABC, which encodes xanthine dehydrogenase (Xdh). Xdh is required for purine salvage pathways. XdhR was previously shown to repress xdhABC expression. We show that XdhR binds the xdhABC–xdhR intergenic region with high affinity (Kd ∼ 0.5 nM). DNaseI footprinting reveals that this complex formation corresponds to XdhR binding the xdhR gene promoter at two adjacent sites; at higher protein concentrations, protection expands to a region that overlaps the transcriptional and translational start sites of xdhABC. While substrates for Xdh have little effect on DNA binding, GTP and ppGpp dissociate the DNA–XdhR complex. Progression of cells to stationary phase, a condition associated with increased (p)ppGpp production, leads to elevated xdhB expression; in contrast, inhibition of Xdh by allopurinol results in xdhB repression. We propose that XdhR is a direct target of (p)ppGpp, and that expression of xdhABC is upregulated during the stringent response to promote purine salvage pathways, maintain GTP homeostasis and ensure continued (p)ppGpp synthesis. During exponential phase growth, basal levels of xdhABC expression may be achieved by GTP serving as a lower‐affinity XdhR ligand.
Quorum sensing is a key regulator for the antifungal and biocontrol activity of chitinase‐producing Chromobacterium sp. C61
Authors: Kim In Seon , Yang Si Young , Park Seur Kee , Kim Young Cheol 
Published: February 2016

SummaryChromobacterium sp. strain C61 has strong biocontrol activity; however, the genetic and biochemical determinants of its plant disease suppression activity are not well understood. Here, we report the identification and characterization of two new determinants of its biocontrol activity. Transposon mutagenesis was used to identify mutants that were deficient in fungal suppression. One of these mutants had an insertion in a homologue of depD, a structural gene in the dep operon, that encodes a protein involved in non‐ribosomal peptide synthesis. In the second mutant, the insertion was in a homologue of the luxI gene, which encodes a homoserine lactone synthase. The luxI– and depD– mutants had no antifungal activity in vitro and a dramatically reduced capacity to suppress various plant diseases in planta. Antifungal production and biocontrol were restored by complementation of the luxI– mutant. Other phenotypes associated with effective biological control, including motility and lytic enzyme secretion, were also affected by the luxI mutation. Biochemical analysis of ethyl acetate extracts of culture filtrates of the mutant and wild‐type strains showed that a key antifungal compound, chromobactomycin, was produced by wild‐type C61 and the complemented luxI– mutant, but not by the luxI– or depD– mutant. These data suggest that multiple biocontrol‐related phenotypes are regulated by homoserine lactones in C61. Thus, quorum sensing plays an essential role in the biological control potential of diverse bacterial lineages.
Induction of systemic disease resistance in Nicotiana benthamiana by the cyclodipeptides cyclo (l‐Pro‐l‐Pro) and cyclo (d‐Pro‐d‐Pro)
Authors: Wu Liming , Wu Huijun , Chen Lina , Zhang Hongyue , Gao Xuewen 
Published: February 2016

SummaryCyclodipeptides, formed from two amino acids by cyclodehydration, are produced naturally by many organisms, and are known to possess a large number of biological activities. In this study, we found that cyclo (l‐Pro‐l‐Pro) and cyclo (d‐Pro‐d‐Pro) (where Pro is proline) could induce defence responses and systemic resistance in Nicotiana benthamiana. Treatment with the two cyclodipeptides led to a reduction in disease severity by Phytophthora nicotianae and Tobacco mosaic virus (TMV) infections compared with controls. Both cyclopeptides triggered stomatal closure, induced reactive oxygen species production and stimulated cytosolic calcium ion and nitric oxide production in guard cells. In addition, the application of cyclodipeptides significantly up‐regulated the expression of the plant defence gene PR‐1a and the PR‐1a protein, and increased cellular salicylic acid (SA) levels. These results suggest that the SA‐dependent defence pathway is involved in cyclodipeptide‐mediated pathogen resistance in N. benthamiana. We report the systemic resistance induced by cyclodipeptides, which sheds light on the potential of cyclodipeptides for the control of plant diseases.
Rituximab protects podocytes and exerts anti‐proteinuric effects in rat adriamycin‐induced nephropathy independent of B‐lymphocytes
Authors: Takahashi Yuichi , Ikezumi Yohei , Saitoh Akihiko 
Published: February 2016

AbstractAimThis study was aimed at examining the effects of treatment with rituximab, a chimeric monoclonal antibody against the protein CD20, in a B‐lymphocyte independent adriamycin‐induced rat model of nephrotic syndrome. Rituximab is an emerging rescue therapy used in patients with complicated nephrotic syndrome and, therefore, we sought to elucidate the apparent B‐lymphocyte independent mechanism underlying its anti‐proteinuric effect.MethodsAdriamycin‐induced nephropathy was established in Wistar rats by intravenously injecting 10 mg/kg of adriamycin, which were then treated with rituximab or purified human IgG weekly and euthanized on day 28. Proteinuria, glomerular expression of sphingomyelin phosphodiesterase acid‐like 3b protein, and podocyte‐related proteins were examined using immunofluorescence staining and a reverse transcription‐polymerase chain reaction.ResultsRituximab treatment of rats with adriamycin‐induced nephropathy significantly reduced urinary protein excretion 14 to 28 days after induction of disease, compared with those treated with purified normal human IgG. Furthermore, rituximab treatment also prevented the reduction of glomerular nephrin and podocin expression on day 28. Double‐immunofluorescence staining revealed that after in vivo administration, rituximab was bound to the glomeruli, which also expressed synaptopodin or sphingomyelin phosphodiesterase, acid‐like 3b. Moreover, sphingomyelin phosphodiesterase, acid‐like 3b expression was significantly decreased on day 28 of adriamycin‐induced nephropathy, which was also prevented by rituximab.ConclusionsThis study demonstrated that rituximab directly affected glomerular podocytes and ameliorated proteinuria in adriamycin‐induced nephropathy in rats. Furthermore, protection of podocyte function by rituximab may be mediated by direct modulation of a sphingomyelin phosphodiesterase, acid‐like 3b‐dependent mechanism.
Co‐expression of the protease furin in Nicotiana benthamiana leads to efficient processing of latent transforming growth factor‐β1 into a biologically active protein
Authors: Wilbers Ruud H. P. , Westerhof Lotte B. , van Raaij Debbie R. , van Adrichem Marloes , Prakasa Andreas D. , Lozano‐Torres Jose L. , Bakker Jaap , Smant Geert , Schots Arjen 
Published: February 2016

SummaryTransforming growth factor beta (TGF‐β) is a signalling molecule that plays a key role in developmental and immunological processes in mammals. Three TGF‐β isoforms exist in humans, and each isoform has unique therapeutic potential. Plants offer a platform for the production of recombinant proteins, which is cheap and easy to scale up and has a low risk of contamination with human pathogens. TGF‐β3 has been produced in plants before using a chloroplast expression system. However, this strategy requires chemical refolding to obtain a biologically active protein. In this study, we investigated the possibility to transiently express active human TGF‐β1 in Nicotiana benthamiana plants. We successfully expressed mature TGF‐β1 in the absence of the latency‐associated peptide (LAP) using different strategies, but the obtained proteins were inactive. Upon expression of LAP‐TGF‐β1, we were able to show that processing of the latent complex by a furin‐like protease does not occur in planta. The use of a chitinase signal peptide enhanced the expression and secretion of LAP‐TGF‐β1, and co‐expression of human furin enabled the proteolytic processing of latent TGF‐β1. Engineering the plant post‐translational machinery by co‐expressing human furin also enhanced the accumulation of biologically active TGF‐β1. This engineering step is quite remarkable, as furin requires multiple processing steps and correct localization within the secretory pathway to become active. Our data demonstrate that plants can be a suitable platform for the production of complex proteins that rely on specific proteolytic processing.
Biogenesis of water splitting by photosystem II during de‐etiolation of barley (Hordeum vulgare L.)
Authors: Shevela Dmitriy , Arnold Janine , Reisinger Veronika , Berends Hans‐Martin , Kmiec Karol , Koroidov Sergey , Bue Ann Kristin , Messinger Johannes , Eichacker Lutz A. 
Published: February 2016

AbstractEtioplasts lack thylakoid membranes and photosystem complexes. Light triggers differentiation of etioplasts into mature chloroplasts, and photosystem complexes assemble in parallel with thylakoid membrane development. Plastids isolated at various time points of de‐etiolation are ideal to study the kinetic biogenesis of photosystem complexes during chloroplast development. Here, we investigated the chronology of photosystem II (PSII) biogenesis by monitoring assembly status of chlorophyll‐binding protein complexes and development of water splitting via O2 production in plastids (etiochloroplasts) isolated during de‐etiolation of barley (Hordeum vulgare L.). Assembly of PSII monomers, dimers and complexes binding outer light‐harvesting antenna [PSII‐light‐harvesting complex II (LHCII) supercomplexes] was identified after 1, 2 and 4 h of de‐etiolation, respectively. Water splitting was detected in parallel with assembly of PSII monomers, and its development correlated with an increase of bound Mn in the samples. After 4 h of de‐etiolation, etiochloroplasts revealed the same water‐splitting efficiency as mature chloroplasts. We conclude that the capability of PSII to split water during de‐etiolation precedes assembly of the PSII‐LHCII supercomplexes. Taken together, data show a rapid establishment of water‐splitting activity during etioplast‐to‐chloroplast transition and emphasize that assembly of the functional water‐splitting site of PSII is not the rate‐limiting step in the formation of photoactive thylakoid membranes.
Long‐term effects of pneumococcal colonization during early childhood wheezing
Authors: Backman Katri , Piippo‐Savolainen Eija , Ollikainen Hertta , Pelli Minna , Koskela Heikki , Korppi Matti 
Published: February 2016

AbstractBackgroundBacterial colonization during wheezing in early childhood has been associated with short‐term relapses of wheezing, but no study has addressed the effects of Streptococcus pneumoniae colonization on long‐term outcome of wheezing. The aim of the present study was therefore to evaluate whether pneumococcal (PNC) colonization during the first wheezing episode in early childhood is a determinant of asthma, atopy or lung function in the long term.MethodsIn 1981–82 83 infants were hospitalized for first wheezing episode at <24 months of age. PNC colonization was defined as positive nasopharyngeal aspirate for S. pneumoniae either in culture or antigen detection on hospital admission. Atopy and repeated wheezing or asthma were diagnosed on all follow‐up visits from infancy until the age of 28–31 years. Spirometry was conducted at the ages of 8–10, 18–20 and 28–31 years.ResultsPNC colonization was found in 25/83 infants (30%) during hospitalization for wheezing in infancy. PNC colonization was not associated with later atopy, repeated wheezing, asthma or lung function at any time during the 30 year follow up.ConclusionPNC colonization during the first wheezing episode in early childhood is not a determinant of subsequent wheezing or later asthma, atopy or lung function in childhood, adolescence or adulthood.
Identification of genes involved in rice seed priming in the early imbibition stage
Authors: Cheng J. , Wang L. , Zeng P. , He Y. , Zhou R. , Zhang H. , Wang Z. 
Published: February 2016

AbstractPhase II of seed imbibition is a critical process during seed priming. To identify genes involved in rice seed priming, the altered proteins between the dry and imbibed (24 h) seeds were compared using a two‐dimensional gel electrophoresis system in this study. Ten significantly changed proteins (fold change ≥ twofold; P < 0.01) were successfully identified, which could be categorised as carbohydrate and protein biosynthesis and metabolism‐related, signalling‐related, storage and stress‐related proteins. A meta‐analysis indicated that the highest expression of the identified genes was at the milk and dough stages and in the endosperm tissue. Quantitative real‐time PCR analysis showed that there was significant variation in gene expression (except FAD‐dependent oxidoreductase) in embryos during seed priming (0–48 h). The expression of genes associated with stress appeared at the early imbibition stage, while those associated with carbohydrate metabolism, protein synthesis and signalling increased at the late imbibition stage. Three identified proteins (glucose‐1‐phosphate adenylyltransferase large subunit, aminotransferase and prolamin precursor) had similar transcript and protein expression patterns in embryos. Based on phenotype and gene expression, the optimal stop time for seed priming is 24 h, when these three genes have relatively low expression, followed by significant induction during imbibition in embryos. These three genes are ideal candidate biomarkers for rice seed priming.
Photosynthetic limitation of several representative subalpine species in the Catalan Pyrenees in summer
Authors: Fernàndez‐Martínez J. , Fleck I. 
Published: February 2016

AbstractInformation on the photosynthetic process and its limitations is essential in order to predict both the capacity of species to adapt to conditions associated with climate change and the likely changes in plant communities. Considering that high‐mountain species are especially sensitive, three species representative of subalpine forests of the Central Catalan Pyrenees: mountain pine (Pinus uncinata Mill.), birch (Betula pendula Roth) and rhododendron (Rhododendron ferrugineum L.) were studied under conditions associated with climate change, such as low precipitation, elevated atmospheric [CO2] and high solar irradiation incident at Earth's surface, in order to detect any photosynthetic limitations. Short‐term high [CO2] increased photosynthesis rates (A) and water use efficiency (WUE), especially in birch and mountain pine, whereas stomatal conductance (gs) was not altered in either species. Birch showed photosynthesis limitation through stomatal closure related to low rainfall, which induced photoinhibition and early foliar senescence. Rhododendron was especially affected by high irradiance, showing early photosynthetic saturation in low light, highest chlorophyll content, lowest gas exchange rates and least photoprotection. Mountain pine had the highest A, photosynthetic capacity (Amax) and light‐saturated rates of net CO2 assimilation (Asat), which were maintained under reduced precipitation. Furthermore, maximum quantum yield (Fv/Fm), thermal energy dissipation, PRI and SIPI radiometric index, and ascorbate content indicated improved photoprotection with respect to the other two species. However, maximum velocity of carboxylation of RuBisco (Vcmax) indicated that N availability would be the main photosynthetic limitation in this species.
Immunolocalization of the Anti‐Müllerian Hormone (AMH) in Caprine Follicles and the Effects of AMH on In Vitro Culture of Caprine Pre‐antral Follicles Enclosed in Ovarian Tissue
Authors: Rocha RMP , Lima LF , Carvalho AA , Chaves RN , Bernuci MP , Rosa‐e‐Silva ACJS , Rodrigues APR , Campello CC , Figueiredo JR 
Published: February 2016

ContentsThe aims of this study were to evaluate the localization, by immunohistochemistry, of the anti‐Müllerian hormone (AMH) in goat ovaries and to investigate its effects on the in vitro survival and development of caprine pre‐antral follicles enclosed in fragments of ovarian tissue. Pre‐antral follicles were cultured in vitro for 1 or 7 days in α‐MEM+ in the absence or presence of kit ligand (KL; 50 ng/ml, positive control) or AMH (50 or 150 ng/ml). The results showed that AMH was localized in oocytes and granulosa cells from the primordial follicle to antral follicle stages. Addition of AMH maintained the percentage of developing follicles, similar to that in the uncultured control; however, the percentage of developing follicles was significantly lower than that in the cultured control and KL. Nonetheless, addition of AMH to the culture medium did not affect survival rates and follicular growth. In conclusion, this study demonstrated that the expression of AMH varies according to the compartment and stage of follicular development. Furthermore, AMH inhibits the activation of caprine primordial follicles.