bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecular analysis of the diets of snakes: changes in prey exploitation during development of the rare smooth snake Coronella austriaca
Authors: Brown David S. , Ebenezer Katie L. , Symondson William O. C. 
Published: July 2013

AbstractReptiles are declining in many parts of the world, mainly due to habitat loss and environmental change. A major factor in this is availability of suitable food. For many animals, dietary requirements shift during developmental stages and a habitat will only be suitable for conserving a species if it supports all stages. Conventional methods for establishing diet often rely on visual recognition of morphologically identifiable features of prey in faeces, regurgitation or stomach contents, which suffer from biases and poor resolution of taxa. DNA‐based techniques facilitate noninvasive analysis of diet from faeces without these constraints. We tested the hypothesis that diet changes during growth stages of smooth snakes (Coronella austriaca), which have a highly restricted distribution in the UK but are widespread in continental Europe. Small numbers of the sympatric grass snake (Natrix natrix) were analysed for comparison. Faecal samples were collected from snakes and prey DNA analysed using PCR, targeting amphibians, reptiles, mammals and invertebrates. Over 85% of smooth snakes were found to have eaten reptiles and 28% had eaten mammals. Predation on mammals increased with age and was entirely absent among juveniles and subadults. Predation on reptiles did not change ontogenetically. Smooth snakes may, therefore, be restricted to areas of sufficiently high reptile densities to support young snakes.
The APSES transcription factor Efg1 is a global regulator that controls morphogenesis and biofilm formation in Candida parapsilosis
Authors: Connolly Leona A. , Riccombeni Alessandro , Grózer Zsuzsana , Holland Linda M. , Lynch Denise B. , Andes David R. , Gácser Attila , Butler Geraldine 
Published: July 2013

SummaryEfg1 (a member of the APSES family) is an important regulator of hyphal growth and of the white‐to‐opaque transition in Candida albicans and very closely related species. We show that in Candida parapsilosis Efg1 is a major regulator of a different morphological switch at the colony level, from a concentric to smooth morphology. The rate of switching is at least 20‐fold increased in an efg1 knockout relative to wild type. Efg1 deletion strains also have reduced biofilm formation, attenuated virulence in an insect model, and increased sensitivity to SDS and caspofungin. Biofilm reduction is more dramatic in in vitro than in in vivo models. An Efg1 paralogue (Efh1) is restricted to Candida species, and does not regulate concentric‐smooth phenotype switching, biofilm formation or stress response. We used ChIP‐seq to identify the Efg1 regulon. A total of 931 promoter regions bound by Efg1 are highly enriched for transcription factors and regulatory proteins. Efg1 also binds to its own promoter, and negatively regulates its expression. Efg1 targets are enriched in binding sites for 93 additional transcription factors, including Ndt80. Our analysis suggests that Efg1 has an ancient role as regulator of development in fungi, and is central to several regulatory networks.
The DivJ, CbrA and PleC system controls DivK phosphorylation and symbiosis in Sinorhizobium meliloti
Authors: Pini Francesco , Frage Benjamin , Ferri Lorenzo , De Nisco Nicole J. , Mohapatra Saswat S. , Taddei Lucilla , Fioravanti Antonella , Dewitte Frederique , Galardini Marco , Brilli Matteo , Villeret Vincent , Bazzicalupo Marco , Mengoni Alessio , Walker Graham C. , Becker Anke , Biondi Emanuele G. 
Published: July 2013

SummarySinorhizobium meliloti is a soil bacterium that invades the root nodules it induces on Medicago sativa, whereupon it undergoes an alteration of its cell cycle and differentiates into nitrogen‐fixing, elongated and polyploid bacteroid with higher membrane permeability. In Caulobacter crescentus, a related alphaproteobacterium, the principal cell cycle regulator, CtrA, is inhibited by the phosphorylated response regulator DivK. The phosphorylation of DivK depends on the histidine kinase DivJ, while PleC is the principal phosphatase for DivK. Despite the importance of the DivJ in C. crescentus, the mechanistic role of this kinase has never been elucidated in other Alphaproteobacteria. We show here that the histidine kinases DivJ together with CbrA and PleC participate in a complex phosphorylation system of the essential response regulator DivK in S. meliloti. In particular, DivJ and CbrA are involved in DivK phosphorylation and in turn CtrA inactivation, thereby controlling correct cell cycle progression and the integrity of the cell envelope. In contrast, the essential PleC presumably acts as a phosphatase of DivK. Interestingly, we found that a DivJ mutant is able to elicit nodules and enter plant cells, but fails to establish an effective symbiosis suggesting that proper envelope and/or low CtrA levels are required for symbiosis.
Postprandial cardiac vagal tone and transient lower esophageal sphincter relaxation (TLESR)
Authors: Kuo P. , Bravi I. , Marreddy U. , Aziz Q. , Sifrim D. 
Published: July 2013

AbstractBackgroundTransient lower esophageal sphincter relaxation (TLESR) is a vagally mediated reflex that occurs most frequently after a meal. Cardiac vagal tone (CVT) decreases after a meal, and correlates with changes in gastric electrical activity. Furthermore, decreased CVT has been reported in patients with gastro‐esophageal reflux disease. We therefore aimed to characterize the association between postprandial changes in CVT and the occurrence of TLESR and reflux.MethodsTen healthy volunteers underwent simultaneous autonomic nervous system, gastric myoelectric activity, lower esophageal‐sphincter pressure, and reflux monitoring for 30 min in the fasting state, followed by a standard meal, and a further 4 h postprandially. Results are in mean ± SEM.Key ResultsThe number of TLESRs (P < 0.0001) and reflux episodes (P < 0.0001) increased after the meal, while CVT decreased (P < 0.01). Cardiac sensitivity to baroreceptor reflex (CSB) showed similar time course changes to CVT (P = 0.06). During the first postprandial hour there was a strong correlation between the number of TLESRs and reflux episodes with CVT (R2 = 0.51 and R2 = 0.50, respectively; P < 0.05). There was also an increase in the dominant power and power ratio on electrogastrography (P < 0.05) after the meal.Conclusions & InferencesIn healthy volunteers, the increase in the number of TLESRs and reflux episodes after a meal occurred mostly at a time of reduced CVT. Further studies should explore whether modulation of CVT can modify frequency of TLESRs and also this relationship should be further explored in patients with reflux disease.
MyD88 is essential for alveolar bone loss induced by Aggregatibacter actinomycetemcomitans lipopolysaccharide in mice
Authors: Madeira M.F.M. , Queiroz‐Junior C.M. , Cisalpino D. , Werneck S.M.C. , Kikuchi H. , Fujise O. , Ryffel B. , Silva T.A. , Teixeira M.M. , Souza D.G. 
Published: July 2013

SummaryAggregatibacter actinomycetemcomitans is a Gram‐negative bacteria highly associated with localized aggressive periodontitis. The recognition of microbial factors, such as lipopolysaccharide from A. actinomycetemcomitans (AaLPS), in the oral environment is made mainly by surface receptors known as Toll‐like receptors (TLR). TLR4 is the major LPS receptor. This interaction leads to the production of inflammatory cytokines by myeloid differentiation primary‐response protein 88 (MyD88) ‐dependent and ‐independent pathways, which may involve the adaptor Toll/interleukin‐1 receptor‐domain‐containing adaptor inducing interferon‐β (TRIF). The aim of this study was to assess the involvement of MyD88 in alveolar bone loss induced by AaLPS in mice. C57BL6/J wild‐type (WT) mice, MyD88, TRIF or TRIF/MyD88 knockout mice received 10 injections of AaLPS strain FDC Y4 (5 μg in 3 μl), in the palatal gingival tissue of the right first molar, every 48 h. Phosphate‐buffered saline was injected in the opposite side and used as control. Animals were sacrificed 24 h after the 10th injection and the maxillae were removed for macroscopic and biochemical analyses. The injections of AaLPS induced significant alveolar bone loss in WT mice. In the absence of MyD88 or TRIF/MyD88 no bone loss induced by AaLPS was observed. In contrast, responses in TRIF−/− mice were similar to those in WT mice. Diminished bone loss in the absence of MyD88 was associated with fewer TRAP‐positive cells and increased expression of osteoblast markers, RUNX2 and osteopontin. There was also reduced tumor necrosis factor‐α production in MyD88−/− mice. There was less osteoclast differentiation of hematopoietic bone marrow cells from MyD88−/− mice after AaLPS stimulation. Hence, the signaling through MyD88 is pivotal for AaLPS‐induced osteoclast formation and alveolar bone loss.
Linkage mapping in the oilseed crop Jatropha curcas L. reveals a locus controlling the biosynthesis of phorbol esters which cause seed toxicity
Authors: King Andrew J. , Montes Luis R. , Clarke Jasper G. , Affleck Julie , Li Yi , Witsenboer Hanneke , van der Vossen Edwin , van der Linde Piet , Tripathi Yogendra , Tavares Evanilda , Shukla Parul , Rajasekaran Thirunavukkarasu , van Loo Eibertus N. , Graham Ian A. 
Published: July 2013

SummaryCurrent efforts to grow the tropical oilseed crop Jatropha curcas L. economically are hampered by the lack of cultivars and the presence of toxic phorbol esters (PE) within the seeds of most provenances. These PE restrict the conversion of seed cake into animal feed, although naturally occurring ‘nontoxic’ provenances exist which produce seed lacking PE. As an important step towards the development of genetically improved varieties of J. curcas, we constructed a linkage map from four F2 mapping populations. The consensus linkage map contains 502 codominant markers, distributed over 11 linkage groups, with a mean marker density of 1.8 cM per unique locus. Analysis of the inheritance of PE biosynthesis indicated that this is a maternally controlled dominant monogenic trait. This maternal control is due to biosynthesis of the PE occurring only within maternal tissues. The trait segregated 3 : 1 within seeds collected from F2 plants, and QTL analysis revealed that a locus on linkage group 8 was responsible for phorbol ester biosynthesis. By taking advantage of the draft genome assemblies of J. curcas and Ricinus communis (castor), a comparative mapping approach was used to develop additional markers to fine map this mutation within 2.3 cM. The linkage map provides a framework for the dissection of agronomic traits in J. curcas, and the development of improved varieties by marker‐assisted breeding. The identification of the locus responsible for PE biosynthesis means that it is now possible to rapidly breed new nontoxic varieties.
Physical activity and working memory in healthy older adults: An ERP study
Authors: Chang Yu‐Kai , Huang Chung‐Ju , Chen Kuan‐Fu , Hung Tsung‐Min 
Published: July 2013

AbstractThis study examined the effects of physical activity on working memory in older adults using both behavioral and neuroelectric measures. Older adults were assigned to either a higher or lower physical activity group, and event‐related potentials were recorded during assessments of a modified Sternberg task. The results indicated that older adults in the higher physical activity group exhibited shorter response times, independent of the working memory load. Enhanced P3 and N1 amplitudes and a decreased P3 latency were observed in the higher physical activity group. These findings suggested that physical activity facilitates working memory by allocating more attentional resources and increasing the efficiency of evaluating the stimulus during the retrieval phase as well as engaging more attentional resources for the early discriminative processes during the encoding phase of a working memory task.
Structure and properties of the Adriatic crust in the central‐eastern Southern Alps (Italy) from local earthquake tomography
Authors: Viganò Alfio , Scafidi Davide , Martin Silvana , Spallarossa Daniele 
Published: July 2013

AbstractStructure and properties of the Adriatic crust were determined from local earthquake tomography around the Giudicarie fault zone (central‐eastern Southern Alps, Italy). Tomographic results, based on well‐suited 436 revised earthquakes (period 1994–2007), have a resolution comparable to the scale of regional geological domains and tectonic structures. The observed strong velocity anomalies correlate well with lithological variations corresponding to different geological domains (particularly magmatic complexes at depth) and with high fracturing and/or presence of fluids along active fault systems (South Giudicarie and Valsugana–Bassano del Grappa–Montello thrusts).
Low‐dose acyclovir prophylaxis for the prevention of herpes simplex virus disease after allogeneic hematopoietic stem cell transplantation
Authors: Kawamura K. , Wada H. , Yamasaki R. , Ishihara Y. , Sakamoto K. , Ashizawa M. , Sato M. , Machishima T. , Terasako K. , Kimura S.‐I. , Kikuchi M. , Nakasone H. , Yamazaki R. , Kanda J. , Kako S. , Tanihara A. , Nishida J. , Kanda Y. 
Published: July 2013

AbstractBackgroundCurrently, acyclovir (ACV) at 1000 mg/day is widely used as prophylaxis in the early phase of hematopoietic stem cell transplant (HSCT) in Japan. However, low‐dose ACV (200 mg/day) has been shown to prevent varicella zoster virus reactivation in the middle and late phases of HSCT.MethodsTherefore, in this study, we decreased the dose of ACV to 200 mg/day in the early phase after HSCT. We analyzed 93 consecutive herpes simplex virus (HSV)‐seropositive patients who underwent allogeneic HSCT for the first time in our center between June 2007 and December 2011.ResultsBefore August 2009, 38 patients received oral ACV at 1000 mg/day (ACV1000) until day 35 after HSCT, whereas 55 patients received oral ACV at 200 mg/day (ACV200) after September 2009. We compared the cumulative incidence of HSV infection in the 2 groups. Oral ACV was changed to intravenous administration because of intolerance in 66% and 45% of the patients in the ACV1000 and ACV200 groups, respectively (P = 0.060). The probability of severe stomatitis (Bearman grade II–III) was 76% and 60% in the ACV1000 and ACV200 groups, respectively (P = 0.12). The number of patients who developed HSV disease before day 100 after HSCT was 0 in the ACV1000 group and 2 in the ACV200 group, with a cumulative incidence of 3.6% (P = 0.43). HSV disease in the latter 2 patients was limited to the lips and tongue and was successfully treated with ACV or valacyclovir at a treatment dose.ConclusionACV at 200 mg/day appeared to be effective for preventing HSV disease in the early phase after HSCT.
Apical F‐actin‐regulated exocytic targeting of NtPPME1 is essential for construction and rigidity of the pollen tube cell wall
Authors: Wang Hao , Zhuang Xiaohong , Cai Yi , Cheung Alice Y. , Jiang Liwen 
Published: July 2013

SummaryIn tip‐confined growing pollen tubes, delivery of newly synthesized cell wall materials to the rapidly expanding apical surface requires spatial organization and temporal regulation of the apical F‐actin filament and exocytosis. In this study, we demonstrate that apical F‐actin is essential for the rigidity and construction of the pollen tube cell wall by regulating exocytosis of Nicotiana tabacum pectin methylesterase (NtPPME1). Wortmannin disrupts the spatial organization of apical F‐actin in the pollen tube tip and inhibits polar targeting of NtPPME1, which subsequently alters the rigidity and pectic composition of the pollen tube cell wall, finally causing growth arrest of the pollen tube. In addition to mechanistically linking cell wall construction and apical F‐actin, wortmannin can be used as a useful tool for studying endomembrane trafficking and cytoskeletal organization in pollen tubes.
‘Real time’ genetic manipulation: a new tool for ecological field studies
Authors: Schäfer Martin , Brütting Christoph , Gase Klaus , Reichelt Michael , Baldwin Ian , Meldau Stefan 
Published: July 2013

SummaryField experiments with transgenic plants often reveal the functional significance of genetic traits that are important for the performance of the plants in their natural environments. Until now, only constitutive overexpression, ectopic expression and gene silencing methods have been used to analyze gene‐related phenotypes in natural habitats. These methods do not allow sufficient control over gene expression for the study of ecological interactions in real time, of genetic traits that play essential roles in development, or of dose‐dependent effects. We applied the sensitive dexamethasone (DEX)‐inducible pOp6/LhGR expression system to the ecological model plant Nicotiana attenuata and established a lanolin‐based DEX application method to facilitate ectopic gene expression and RNA interference‐mediated gene silencing in the field and under challenging conditions (e.g. high temperature, wind and UV radiation). Fully established field‐grown plants were used to silence phytoene desaturase and thereby cause photobleaching only in specific plant sectors, and to activate expression of the cytokinin (CK) biosynthesis gene isopentenyl transferase (ipt). We used ipt expression to analyze the role of CKs in both the glasshouse and the field to understand resistance to the native herbivore Tupiocoris notatus, which attacks plants at small spatial scales. By spatially restricting ipt expression and elevating CK levels in single leaves, damage by T. notatus increased, demonstrating the role of CKs in this plant–herbivore interaction at a small scale. As the arena of most ecological interactions is highly constrained in time and space, these tools will advance the genetic analysis of dynamic traits that matter for plant performance in nature.
Use of 222radon as a simple tool for surface water–groundwater connectivity assessment: a case study in the arid Limarí basin, north‐central Chile
Authors: Oyarzún Ricardo , Jofré Elizabeth , Maturana Hugo , Oyarzún Jorge , Aguirre Evelyn 
Published: July 2013

AbstractWe report the results from a pilot study on the use of 222Rn (222radon) for river–aquifer interaction assessment in the Limarí watershed, north‐central Chile. Previous studies on this tool for such applications are not abundant at international level, and no records exist for Chile. The lowest 222Rn levels (less than 1000 Bq/m3) were found in water reservoirs, thus indicating that this isotope is easily lost (and therefore usually absent) in surface waters. Conversely, the highest levels of 222Rn were found in groundwater, with maxima activities around 20 000 Bq/m3. This remarkable contrast allowed clear identification of zones of surface water–groundwater connectivity in the searched watershed domain.
Pharmacokinetics and Pharmacodynamics of Once-Daily Administration of Intravenous Tobramycin in Adult Patients with Cystic Fibrosis Hospitalized for an Acute Pulmonary Exacerbation
Authors: Butterfield Jill M. , Lodise Thomas P. , Beegle Scott , Rosen Jonathan , Farkas Joshua , Pai Manjunath P. 
Published: July 2013

ABSTRACT
The serum pharmacokinetic profile of intravenous (i.v.) tobramycin administration was characterized for a sample of nine adult patients with cystic fibrosis (CF) who were hospitalized for an acute pulmonary exacerbation. Current recommended i.v. tobramycin dosing protocols are predicted through modeling and simulation to be suboptimal. Empirical tobramycin regimens of ≥15 mg/kg of body weight administered i.v. once daily should be evaluated for adult patients with CF to optimize outcomes.
Dried Blood Spot Analysis Suitable for Therapeutic Drug Monitoring of Voriconazole, Fluconazole, and Posaconazole
Authors: van der Elst Kim C. M. , Span Lambert F. R. , van Hateren Kai , Vermeulen Karin M. , van der Werf Tjip S. , Greijdanus Ben , Kosterink Jos G. W. , Uges Donald R. A. , Alffenaar Jan-Willem C. 
Published: July 2013

ABSTRACT

Invasive aspergillosis and candidemia are important causes of morbidity and mortality in immunocompromised and critically ill patients. The triazoles voriconazole, fluconazole, and posaconazole are widely used for the treatment and prophylaxis of these fungal infections. Due to the variability of the pharmacokinetics of the triazoles among and within individual patients, therapeutic drug monitoring is important for optimizing the efficacy and safety of antifungal treatment. A dried blood spot (DBS) analysis was developed and was clinically validated for voriconazole, fluconazole, and posaconazole in 28 patients. Furthermore, a questionnaire was administered to evaluate the patients' opinions of the sampling method. The DBS analytical method showed linearity over the concentration range measured for all triazoles. Results for accuracy and precision were within accepted ranges; samples were stable at room temperature for at least 12 days; and different hematocrit values and blood spot volumes had no significant influence. The ratio of the drug concentration in DBS samples to that in plasma was 1.0 for voriconazole and fluconazole and 0.9 for posaconazole. Sixty percent of the patients preferred DBS analysis as a sampling method; 15% preferred venous blood sampling; and 25% had no preferred method. There was significantly less perception of pain with the DBS sampling method (
P
= 0.021). In conclusion, DBS analysis is a reliable alternative to venous blood sampling and can be used for therapeutic drug monitoring of voriconazole, fluconazole, and posaconazole. Patients were satisfied with DBS sampling and had less pain than with venous sampling. Most patients preferred DBS sampling to venous blood sampling.
Trimethoprim Resistance of Dihydrofolate Reductase Variants from Clinical Isolates of Pneumocystis jirovecii
Authors: Queener S. F. , Cody V. , Pace J. , Torkelson P. , Gangjee A. 
Published: July 2013

ABSTRACT

Pneumocystis jirovecii
is an opportunistic pathogen that causes serious pneumonia in immunosuppressed patients. Standard therapy and prophylaxis include trimethoprim (TMP)-sulfamethoxazole; trimethoprim in this combination targets dihydrofolate reductase (DHFR). Fourteen clinically observed variants of
P. jirovecii
DHFR were produced recombinantly to allow exploration of the causes of clinically observed failure of therapy and prophylaxis that includes trimethoprim. Six DHFR variants (S31F, F36C, L65P, A67V, V79I, and I158V) showed resistance to inhibition by trimethoprim, with

K
i

values for trimethoprim 4-fold to 100-fold higher than those for the wild-type
P. jirovecii
DHFR. An experimental antifolate with more conformational flexibility than trimethoprim showed strong activity against one trimethoprim-resistant variant. The two variants that were most resistant to trimethoprim (F36C and L65P) also had increased

K
m

values for dihydrofolic acid (DHFA). The catalytic rate constant (
k
cat
) was unchanged for most variant forms of
P. jirovecii
DHFR but was significantly lowered in F36C protein; one naturally occurring variant with two amino acid substitutions (S106P and E127G) showed a doubling of
k
cat
, as well as a

K
m

for NADPH half that of the wild type. The strongest resistance to trimethoprim occurred with amino acid changes in the binding pocket for DHFA or trimethoprim, and the strongest effect on binding of NADPH was linked to a mutation involved in binding the phosphate group of the cofactor. This study marks the first confirmation that naturally occurring mutations in the gene for DHFR from
P. jirovecii
produce variant forms of DHFR that are resistant to trimethoprim and may contribute to clinically observed failures of standard therapy or prophylaxis.