bluuebunny/crossref_metadata_2025_split huggingface dataset:
Toll‐like receptors 2 and 4 modulate the contractile response induced by serotonin in mouse ileum: analysis of the serotonin receptors involved
Authors: Forcén R. , Latorre E. , Pardo J. , Alcalde A. I. , Murillo M. D. , Grasa L. 
Published: June 2015

AbstractBackgroundMicrobiota through toll‐like receptors (TLR) may regulate gastrointestinal motility by activating neuroendocrine mechanisms. We evaluated the influence of TLR2 and TLR4 in the spontaneous contractions and serotonin (5‐HT)‐induced motor response in mouse ileum, and the 5‐HT receptors involved.MethodsMuscle contractility studies to evaluate the spontaneous intestinal motility and the response to 5‐HT were performed in the ileum from wild type (WT), TLR2−/−, TLR4−/−, and TLR2/4 double knockout (DKO) mice. 5‐HT receptor expression was determined by real‐time PCR.Key ResultsThe amplitude of spontaneous contractions in ileum was higher in TLR2−/−, TLR4−/−, and TLR2/4 DKO mice with respect to WT. 5‐HT evoked concentration‐dependent contractile responses in the ileum from TLR2−/− and TLR4−/− mice similar to WT. However, in ileum from TLR2/4 DKO, 5‐HT did not induce any contractile response. Expression of 5‐HT2A, 5‐HT2B, 5‐HT2C, and 5‐HT3 receptors resulted increased in ileum from TLR4−/− and TLR2/4 DKO. Expression of the 5‐HT4 receptor was diminished in TLR2−/− and TLR2/4 DKO. High levels of 5‐HT7 receptor expression were found in TLR2/4 DKO but not in TLR2−/− or TLR4−/−. In WT and TLR4−/−, 5‐HT2, 5‐HT3, 5‐HT4, and 5‐HT7 receptor antagonists reduced the contractile response evoked by 5‐HT. In TLR2−/− mice, 5‐HT4 antagonist did not reduce the 5‐HT response. In TLR2/4 DKO mice, only 5‐HT4 and 5‐HT7 receptor antagonists reduced the relaxing response induced by 5‐HT.Conclusions & InferencesTLR2 and TLR4 signaling may modulate the spontaneous contractions and the serotonin contractile response by acting on 5‐HT2, 5‐HT3, 5‐HT4, and 5‐HT7 receptors.
Treatment of solar urticaria using antihistamine and leukotriene receptor antagonist combinations tailored to disease severity
Authors: Levi Assi , Enk Claes D. 
Published: June 2015

SummaryBackgroundSolar urticarial (SU) is characterized by erythema, whealing, and/or pruritus occurring minutes after sun exposure. Treatment is difficult and often unsatisfactory.ObjectivesTo determine the action spectra and minimal urticaria dose (MUD) and to tailor a treatment regimen graded according to disease severity in a series of patients with SU.Patients and MethodsEleven patients (seven females, four males, age range: 5–60 years) with a clinical history suggestive of SU, verified by photo‐provocation tests to ultraviolet A (UVA), visible light, and/or UVB, were treated with various combinations of antihistamines and leukotriene receptor antagonist.ResultsAll patients were sensitive to visible light (median MUD 50 J/cm2). Three patients were sensitive to UVA (median MUD 3.75 J/cm2), and one patient was sensitive to UVB (MUD of 0.03 J/cm2). Two patients experienced a spontaneous remission without treatment. One patient declined treatment. The remaining eight patients were managed by a combination of antihistamines (desloratidine, fexofenadine, cetirizine HCl) and a leukotriene receptor antagonist (montelukast). Seven of the 8 patients experienced a sustained remission of symptoms and signs following treatment.ConclusionsPhotoprovocation for SU with determination of action spectra and MUD enables specifically tailored treatment regimens consisting of combinations of antihistamines and leukotriene receptor antagonist.
Two‐year post‐transplantation cytomegalovirus DNAemia in asymptomatic kidney transplant recipients: incidence, risk factors, and outcome
Authors: Viot B. , Garrigue I. , Taton B. , Bachelet T. , Moreau J.‐F. , Dechanet‐Merville J. , Merville P. , Couzi L. 
Published: June 2015

AbstractBackgroundThe incidence and the impact of asymptomatic cytomegalovirus (CMV) DNAemia occurring after the first year post transplantation is unknown.MethodsIn this retrospective cross‐sectional study, we analyzed the incidence, risk factors, and impact of 2‐year post‐transplantation asymptomatic CMV DNAemia (2YCD) on graft function. We included 892 consecutive asymptomatic kidney transplant recipients transplanted for at least 2 years and all were monitored using whole blood CMV quantitative nucleic acid amplification testing (CMV‐QNAT).ResultsTwenty‐eight patients displayed 2YCD (3.1%). Using multivariate analysis in 578 patients, we found that female gender (odds ratio [OR] = 2.57, P = 0.02), a past history of CMV drug‐resistance mutation (OR = 8.73, P = 0.005), and corticosteroid use (OR = 2.37, P = 0.03) were independently associated with an increased risk of 2YCD. 2YCD was associated with an increased incidence of subsequent CMV disease over the year following its diagnosis (7% vs. 0.6%, P = 0.02). Patients with 2YCD also exhibited a declining estimated glomerular filtration rate more frequently (77%) than patients with a negative CMV‐QNAT (56%, P = 0.02).Conclusion2YCD appears to be a rare entity, which appears to be associated with chronic graft dysfunction.
Peroxide‐based oxygen generating topical wound dressing for enhancing healing of dermal wounds
Authors: Chandra Prafulla K. , Ross Christina L. , Smith Leona C. , Jeong Seon S. , Kim Jaehyun , Yoo James J. , Harrison Benjamin S. 
Published: June 2015

AbstractOxygen generating biomaterials represent a new trend in regenerative medicine that aims to generate and supply oxygen at the site of requirement, to support tissue healing and regeneration. To enhance the healing of dermal wounds, we have developed a highly portable, in situ oxygen generating wound dressings that uses sodium percarbonate (SPO) and calcium peroxide (CPO) as chemical oxygen sources. The dressing continuously generated oxygen for more than 3 days, after which it was replaced. In the in vivo testing on porcine full‐thickness porcine wound model, the SPO/CPO dressing showed enhanced wound healing during the 8 week study period. Quantitative measurements of wound healing related parameters, such as wound closure, reepithelialization, epidermal thickness and collagen content of dermis showed that supplying oxygen topically using the SPO/CPO dressing significantly accelerated the wound healing. An increase in neovascularization, as determined using Von Willebrand factor (vWF) and CD31 staining, was also observed in the presence of SPO/CPO dressing. This novel design for a wound dressing that contains oxygen generating biomaterials (SPO/CPO) for supplying topical oxygen, may find utility in treating various types of acute to chronic wounds.
High levels of positive end‐expiratory pressure preserve diaphragmatic contractility during acute respiratory distress syndrome in rats
Authors: Jiao Guang‐Yu , Hao Li‐Ying , Chen Lie , Gao Chun‐E , Feng Rui , Hu Hui‐Yuan , Tan Shu‐Tao , Wang Meng‐Meng , Zhong Bin , Wang Ping‐Ping 
Published: June 2015

New Findings
What is the central question of this study?
Higher levels of positive end‐expiratory pressure (PEEP) have recently been used in patients with acute respiratory distress syndrome (ARDS). In normal physiological conditions, the ability of the diaphragm to generate pressure is reduced when the lung volume is elevated beyond its functional residual capacity. It is unknown whether higher levels of PEEP will have a negative impact on diaphragmatic contraction in the presence of the pathophysiology of ARDS.

What is the main finding and its importance?
Mechanical ventilation with higher levels of PEEP reduced lung injury, improved diaphragmatic contractility and increased the expression of both dihydropyridine receptor and ryanodine receptor in the diaphragms of rats with ARDS.Higher levels of positive end‐expiratory pressure (PEEP) have recently been used in patients with acute respiratory distress syndrome (ARDS). In normal physiological conditions, the ability of the diaphragm to generate pressure is reduced when the lung volume is elevated beyond its functional residual capacity. Thus, it is critical to understand whether higher levels of PEEP will have a negative impact on diaphragmatic contraction in the presence of the pathophysiology of ARDS. This study was designed to determine whether higher levels of PEEP reduce diaphragmatic contractility in a rat model of ARDS generated using i.p. lipopolysaccharide. Forty rats were randomly assigned to the following five groups: a control group with no special treatment; an ARDS group with no mechanical ventilation; and three ARDS groups with mechanical ventilation with PEEP at 0, 5 or 10 cmH2O, respectively. We found that mechanical ventilation with PEEP reduced lung injury, improved diaphragmatic contractility and increased the expression of both dihydropyridine receptor and ryanodine receptor in the diaphragms of rats with ARDS. These changes were most significant at a PEEP of 10 cmH2O among all applied levels of PEEP. In conclusion, using a rat ARDS model, this study confirmed that diaphragmatic contractility was preserved by mechanical ventilation with high levels of PEEP.
Tracks through the genome to physiological events
Authors: Lipscombe Diane , Pan Jen Q. , Schorge Stephanie 
Published: June 2015

New Findings

What is the topic of this review?
We discuss tools available to access genome‐wide data sets that harbour cell‐specific, brain region‐specific and tissue‐specific information on exon usage for several species, including humans. In this Review, we demonstrate how to access this information in genome databases and its enormous value to physiology.

What advances does it highlight?
The sheer scale of protein diversity that is possible from complex genes, including those that encode voltage‐gated ion channels, is vast. But this choice is critical for a complete understanding of protein function in the most physiologically relevant context.

Many proteins of great interest to physiologists and neuroscientists are structurally complex and located in specialized subcellular domains, such as neuronal synapses and transverse tubules of muscle. Genes that encode these critical signalling molecules (receptors, ion channels, transporters, enzymes, cell adhesion molecules, cell–cell interaction proteins and cytoskeletal proteins) are similarly complex. Typically, these genes are large; human Dystrophin (DMD) encodes a cytoskeletal protein of muscle and it is the largest naturally occurring gene at a staggering 2.3 Mb. Large genes contain many non‐coding introns and coding exons; human Titin (TTN), which encodes a protein essential for the assembly and functioning of vertebrate striated muscles, has over 350 exons and consequently has an enormous capacity to generate different forms of Titin mRNAs that have unique exon combinations. Functional and pharmacological differences among protein isoforms originating from the same gene may be subtle but nonetheless of critical physiological significance. Standard functional, immunological and pharmacological approaches, so useful for characterizing proteins encoded by different genes, typically fail to discriminate among splice isoforms of individual genes. Tools are now available to access genome‐wide data sets that harbour cell‐specific, brain region‐specific and tissue‐specific information on exon usage for several species, including humans. In this Review, we demonstrate how to access this information in genome databases and its enormous value to physiology.
Metabolic aspects of high‐altitude adaptation in Tibetans
Authors: Ge Ri‐Li , Simonson Tatum S. , Gordeuk Victor , Prchal Josef T. , McClain Donald A. 
Published: June 2015

New Findings

What is the topic of this review?
The topic of this review is how Tibetans have adapted genetically to high altitude, particularly with reference to altitude‐induced changes in metabolism.

What advances does it highlight?
It highlights recent work on metabolic phenotyping in Tibetans and demonstrates that selected genetic haplotypes influence their metabolism of fats and glucose.

Recent studies have identified genes involved in high‐altitude adaptation in Tibetans. Three of these genes (EPAS1, EGLN1 and PPARA) are associated with decreased haemoglobin levels compared with non‐Tibetans living at altitude. Consistent with the phenotype, EGLN1 in Tibetans has a gain‐of‐function mutation that confers a higher affinity for oxygen, hence less sensitivity to hypoxia. Considering the demands imposed upon metabolism in meeting energy demands despite limitations on fuel oxidation, we hypothesized that other selected genes might alter metabolism to allow adaptation to altitude despite the desensitization of the upstream hypoxia sensing caused by the EGLN1 mutation that results in the failure to sense hypoxia. A shift in fuel preference to glucose oxidation and glycolysis at the expense of fatty acid oxidation would provide adaptation to decreased oxygen availability. Measurements of serum metabolites from Tibetans living at high altitude are consistent with this hypothesis; the EPAS1 haplotype is significantly associated with increased lactate levels (suggesting increased anaerobic metabolism), and the PPARA haplotype and serum free fatty acids are positively related (suggesting decreased fat oxidation). These data suggest that the high‐altitude adaptations may offer protection from diabetes at high altitude but increase the risk of diabetes at lower elevations and/or with adoption of a non‐traditional diet. It should also be considered in future work in the field that because iron is a cofactor for EGLN1, there may be significant associations of phenotypes with the significant degrees of variation seen in tissue iron among human populations.
Physiology, Genomics, and Pathway Engineering of an Ethanol-Tolerant Strain of Clostridium phytofermentans
Authors: Tolonen Andrew C. , Zuroff Trevor R. , Ramya Mohandass , Boutard Magali , Cerisy Tristan , Curtis Wayne R. 
Published: June 2015

ABSTRACT

Novel processing strategies for hydrolysis and fermentation of lignocellulosic biomass in a single reactor offer large potential cost savings for production of biocommodities and biofuels. One critical challenge is retaining high enzyme production in the presence of elevated product titers. Toward this goal, the cellulolytic, ethanol-producing bacterium
Clostridium phytofermentans
was adapted to increased ethanol concentrations. The resulting ethanol-tolerant (ET) strain has nearly doubled ethanol tolerance relative to the wild-type level but also reduced ethanol yield and growth at low ethanol concentrations. The genome of the ET strain has coding changes in proteins involved in membrane biosynthesis, the Rnf complex, cation homeostasis, gene regulation, and ethanol production. In particular, purification of the mutant bifunctional acetaldehyde coenzyme A (CoA)/alcohol dehydrogenase showed that a G609D variant abolished its activities, including ethanol formation. Heterologous expression of
Zymomonas mobilis
pyruvate decarboxylase and alcohol dehydrogenase in the ET strain increased cellulose consumption and restored ethanol production, demonstrating how metabolic engineering can be used to overcome disadvantageous mutations incurred during adaptation to ethanol. We discuss how genetic changes in the ET strain reveal novel potential strategies for improving microbial solvent tolerance.
Microbial Infections Are Associated with Embryo Mortality in Arctic-Nesting Geese
Authors: Hansen Cristina M. , Meixell Brandt W. , Van Hemert Caroline , Hare Rebekah F. , Hueffer Karsten 
Published: June 2015

ABSTRACT

To address the role of bacterial infection in hatching failure of wild geese, we monitored embryo development in a breeding population of Greater white-fronted geese (
Anser albifrons
) on the Arctic Coastal Plain of Alaska. During 2013, we observed mortality of normally developing embryos and collected 36 addled eggs for analysis. We also collected 17 infertile eggs for comparison. Using standard culture methods and gene sequencing to identify bacteria within collected eggs, we identified a potentially novel species of
Neisseria
in 33 eggs,
Macrococcus caseolyticus
in 6 eggs, and
Streptococcus uberis
and
Rothia nasimurium
in 4 eggs each. We detected seven other bacterial species at lower frequencies. Sequences of the 16S rRNA genes from the
Neisseria
isolates most closely matched sequences from
N. animaloris
and
N. canis
(96 to 97% identity), but phylogenetic analysis suggested substantial genetic differentiation between egg isolates and known
Neisseria
species. Although definitive sources of the bacteria remain unknown, we detected
Neisseria
DNA from swabs of eggshells, nest contents, and cloacae of nesting females. To assess the pathogenicity of bacteria identified in contents of addled eggs, we inoculated isolates of
Neisseria
,
Macrococcus
,
Streptococcus
, and
Rothia
at various concentrations into developing chicken eggs. Seven-day mortality rates varied from 70 to 100%, depending on the bacterial species and inoculation dose. Our results suggest that bacterial infections are a source of embryo mortality in wild geese in the Arctic.
pSW2, a Novel Low-Temperature-Inducible Gene Expression Vector Based on a Filamentous Phage of the Deep-Sea Bacterium Shewanella piezotolerans WP3
Authors: Yang Xin-Wei , Jian Hua-Hua , Wang Feng-Ping 
Published: June 2015

ABSTRACT

A low-temperature-inducible protein expression vector (pSW2) based on a filamentous phage (SW1) of the deep-sea bacterium
Shewanella piezotolerans
WP3 was constructed. This vector replicated stably in
Escherichia coli
and
Shewanella
species, and its copy number increased at low temperatures. The pSW2 vector can be utilized as a complementation plasmid in WP3, and it can also be used for the production of complex cytochromes with multiple heme groups, which has the potential for application for metal ion recovery or bioremediation. Promoters of low-temperature-inducible genes in WP3 were fused into the vector to construct a series of vectors for enhancing protein expression at low temperature. The maximum green fluorescent protein intensity was obtained when the promoter for the
hfq
gene was used. The WP3/pSW2 system can efficiently produce a patatin-like protein (PLP) from a metagenomic library that tends to form inclusion bodies in
E. coli
. The yields of PLP in the soluble fraction were 8.3 mg/liter and 4.7 mg/liter of culture at 4°C and 20°C, respectively. Moreover, the pSW2 vector can be broadly utilized in other
Shewanella
species, such as
S. oneidensis
and
S. psychrophila
.
Acromyrmex Leaf-Cutting Ants Have Simple Gut Microbiota with Nitrogen-Fixing Potential
Authors: Sapountzis Panagiotis , Zhukova Mariya , Hansen Lars H. , Sørensen Søren J. , Schiøtt Morten , Boomsma Jacobus J. 
Published: June 2015

ABSTRACT

Ants and termites have independently evolved obligate fungus-farming mutualisms, but their gardening procedures are fundamentally different, as the termites predigest their plant substrate whereas the ants deposit it directly on the fungus garden. Fungus-growing termites retained diverse gut microbiota, but bacterial gut communities in fungus-growing leaf-cutting ants have not been investigated, so it is unknown whether and how they are specialized on an exclusively fungal diet. Here we characterized the gut bacterial community of Panamanian
Acromyrmex
species, which are dominated by only four bacterial taxa:
Wolbachia
,
Rhizobiales
, and two
Entomoplasmatales
taxa. We show that the
Entomoplasmatales
can be both intracellular and extracellular across different gut tissues,
Wolbachia
is mainly but not exclusively intracellular, and the
Rhizobiales
species is strictly extracellular and confined to the gut lumen, where it forms biofilms along the hindgut cuticle supported by an adhesive matrix of polysaccharides. Tetracycline diets eliminated the
Entomoplasmatales
symbionts but hardly affected
Wolbachia
and only moderately reduced the
Rhizobiales
, suggesting that the latter are protected by the biofilm matrix. We show that the
Rhizobiales
symbiont produces bacterial NifH proteins that have been associated with the fixation of nitrogen, suggesting that these compartmentalized hindgut symbionts alleviate nutritional constraints emanating from an exclusive fungus garden diet reared on a substrate of leaves.
Implications of Genome-Based Discrimination between Clostridium botulinum Group I and Clostridium sporogenes Strains for Bacterial Taxonomy
Authors: Weigand Michael R. , Pena-Gonzalez Angela , Shirey Timothy B. , Broeker Robin G. , Ishaq Maliha K. , Konstantinidis Konstantinos T. , Raphael Brian H. 
Published: June 2015

ABSTRACT

Taxonomic classification of
Clostridium botulinum
is based on the production of botulinum neurotoxin (BoNT), while closely related, nontoxic organisms are classified as
Clostridium sporogenes
. However, this taxonomic organization does not accurately mirror phylogenetic relationships between these species. A phylogenetic reconstruction using 2,016 orthologous genes shared among strains of
C. botulinum
group I and
C. sporogenes
clearly separated these two species into discrete clades which showed ∼93% average nucleotide identity (ANI) between them. Clustering of strains based on the presence of variable orthologs revealed 143
C. sporogenes
clade-specific genetic signatures, a subset of which were further evaluated for their ability to correctly classify a panel of presumptive
C. sporogenes
strains by PCR. Genome sequencing of several
C. sporogenes
strains lacking these signatures confirmed that they clustered with
C. botulinum
strains in a core genome phylogenetic tree. Our analysis also identified
C. botulinum
strains that contained
C. sporogenes
clade-specific signatures and phylogenetically clustered with
C. sporogenes
strains. The genome sequences of two
bont/B2
-containing strains belonging to the
C. sporogenes
clade contained regions with similarity to a
bont
-bearing plasmid (pCLD), while two different strains belonging to the
C. botulinum
clade carried
bont/B2
on the chromosome. These results indicate that
bont/B2
was likely acquired by
C. sporogenes
strains through horizontal gene transfer. The genome-based classification of these species used to identify candidate genes for the development of rapid assays for molecular identification may be applicable to additional bacterial species that are challenging with respect to their classification.