bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficacy of an emollient cream in the treatment of xerosis in diabetic foot: a double‐blind, randomized, vehicle‐controlled clinical trial
Authors: Martini J. , Huertas C. , Turlier V. , Saint‐Martory C. , Delarue A. 
Published: December 2016

AbstractBackgroundPeripheral neuronal impairment compromises foot health in patients with diabetes. Clinically, xerosis is the most common mild complication, but it should not be underestimated. An effective treatment must be able to restore the cutaneous barrier and prevent water loss, to maintain adequate hydration and protection.ObjectiveThis study aimed to assess the efficacy of an emollient cream on foot xerosis in patients with diabetes.MethodsThis is a prospective, multicenter, randomized, double‐blind contralateral vehicle‐controlled study in 57 patients with diabetes. Patients were treated twice daily for 27 ± 2 days with the study emollient containing glycerol 15%, liquid and soft paraffin 10%, glycerol monostearate, stearic acid, polydimethylcyclosiloxane, silicone oil, macrogol 600, trolamine, propyl parahydroxybenzoate and purified water (Dexeryl®; Pierre Fabre Medicament, Boulogne, France) or its vehicle (glycerol monostearate, stearic acid, polydimethylcyclosiloxane, silicone oil, macrogol 600, trolamine, propyl parahydroxybenzoate and purified water). Efficacy was assessed after a 28‐day treatment period using a validated score [Xerosis Assessment Scale (XAS) score], instrumental measurements and subjective assessment.ResultsThe XAS score decreased to 3.2 ± 2.6 points with the emollient and 4.1 ± 2.3 with the vehicle (P = 0.001). Improvement was observed from day 14 (P = 0.012). Compared with the vehicle, the emollient also significantly improved the overall skin score, hydration index, D‐Squame® (CuDerm Corporation, Dallas, TX, USA) test, skin roughness and patients’ opinions.ConclusionTreatment with an emollient is effective for improving foot xerosis in patients with diabetes.
Inner ear development in cetaceans
Authors: Thean Tara , Kardjilov Nikolay , Asher Robert J. 
Published: December 2016

AbstractCetaceans face the challenge of maintaining equilibrium underwater and obtaining sensory input within a dense, low‐visibility medium. The cetacean ear represents a key innovation that marked their evolution from terrestrial artiodactyls to among the most fully aquatic mammals in existence. Using micro‐CT and histological data, we document shape and size changes in the cetacean inner ear during ontogeny, and demonstrate that, as a proportion of gestation time, the cetacean inner ear is precocial in its growth compared with that of suid artiodactyls. Cetacean inner ears begin ossifying and reach near‐adult shape as early as at 32% of the gestation period, and near‐adult dimensions as early as at 27% newborn total length. Our earliest embryos with measurable inner ears (13% newborn length) exhibit a flattened cochlea (i.e. smaller distance from cochlear apex to round window) compared with later and adult stages. Inner ears of Sus scrofa have neither begun ossifying nor reached near‐adult dimensions at 55% of the gestation period, but have an adult‐like ratio of cochlear diameters to each other, suggesting an adult‐like shape. The precocial development of the cetacean inner ear complements previous work demonstrating precocial development of other cetacean anatomical features such as the locomotor muscles to facilitate swimming at the moment of birth.
The opsin genes of amazonian cichlids
Authors: Escobar‐Camacho Daniel , Ramos Erica , Martins Cesar , Carleton Karen L. 
Published: December 2016

AbstractVision is a critical sense for organismal survival with visual sensitivities strongly shaped by the environment. Some freshwater fishes with a Gondwanan origin are distributed in both South American rivers including the Amazon and African rivers and lakes. These different habitats likely required adaptations to murky and clear environments. In this study, we compare the molecular basis of Amazonian and African cichlid fishes’ visual systems. We used next‐generation sequencing of genomes and retinal transcriptomes to examine three Amazonian cichlid species. Genome assemblies revealed six cone opsin classes (SWS1, SWS2B, SWS2A, RH2B, RH2A and LWS) and rod opsin (RH1). However, the functionality of these genes varies across species with different pseudogenes found in different species. Our results support evidence of an RH2A gene duplication event that is shared across both cichlid groups, but which was probably followed by gene conversion. Transcriptome analyses show that Amazonian species mainly express three opsin classes (SWS2A, RH2A and LWS), which likely are a good match to the long‐wavelength‐oriented light environment of the Amazon basin. Furthermore, analysis of amino acid sequences suggests that the short‐wavelength‐sensitive genes (SWS2B, SWS2A) may be under selective pressures to shift their spectral properties to a longer‐wavelength visual palette. Our results agree with the ‘sensitivity hypothesis’ where the light environment causes visual adaptation. Amazonian cichlid visual systems are likely adapting through gene expression, gene loss and possibly spectral tuning of opsin sequences. Such mechanisms may be shared across the Amazonian fish fauna.
Evidence for microbial local adaptation in nature
Authors: Kraemer Susanne A. , Boynton Primrose J. 
Published: December 2016

AbstractLocal adaptation is an outcome of divergent selection on microbial populations and has been linked to the immense genetic diversity of microbes observed in nature. Because it is difficult to study microbes in their natural habitats, most tests of microbial local adaptation have been performed in model laboratory systems; as a result, microbiologists have limited understanding of local adaptation among natural microbial populations. In this review, we summarize the evidence for microbial local adaptation in nature. Local adaptation has been most frequently studied, and most frequently found, in host–pathogen systems. We argue that more research is needed to understand the prevalence of local adaptation in free‐living microbial populations. However, researchers will need to overcome a variety of logistical and conceptual challenges when studying natural microbial local adaptation, including a lack of solid understanding of many microbes’ natural histories. We propose strategies to facilitate future natural history research on divergent selection. We also summarize laboratory experimental work investigating the ecological and evolutionary processes leading to local adaptation. Microbiologists’ ongoing challenge is to integrate the valuable knowledge gained from laboratory experiments into well‐designed field experiments. Such integration will help us understand the prevalence of, and circumstances leading to, local adaptation among microorganisms.
The on‐again, off‐again relationship between mitochondrial genomes and species boundaries
Authors: Sloan Daniel B. , Havird Justin C. , Sharbrough Joel 
Published: December 2016

AbstractThe study of reproductive isolation and species barriers frequently focuses on mitochondrial genomes and has produced two alternative and almost diametrically opposed narratives. On one hand, mtDNA may be at the forefront of speciation events, with co‐evolved mitonuclear interactions responsible for some of the earliest genetic incompatibilities arising among isolated populations. On the other hand, there are numerous cases of introgression of mtDNA across species boundaries even when nuclear gene flow is restricted. We argue that these seemingly contradictory patterns can result from a single underlying cause. Specifically, the accumulation of deleterious mutations in mtDNA creates a problem with two alternative evolutionary solutions. In some cases, compensatory or epistatic changes in the nuclear genome may ameliorate the effects of mitochondrial mutations, thereby establishing coadapted mitonuclear genotypes within populations and forming the basis of reproductive incompatibilities between populations. Alternatively, populations with high mitochondrial mutation loads may be rescued by replacement with a more fit, foreign mitochondrial haplotype. Coupled with many nonadaptive mechanisms of introgression that can preferentially affect cytoplasmic genomes, this form of adaptive introgression may contribute to the widespread discordance between mitochondrial and nuclear genealogies. Here, we review recent advances related to mitochondrial introgression and mitonuclear incompatibilities, including the potential for cointrogression of mtDNA and interacting nuclear genes. We also address an emerging controversy over the classic assumption that selection on mitochondrial genomes is inefficient and discuss the mechanisms that lead lineages down alternative evolutionary paths in response to mitochondrial mutation accumulation.
Habitat continuity and stepping‐stone oceanographic distances explain population genetic connectivity of the brown alga Cystoseira amentacea
Authors: Buonomo Roberto , Assis Jorge , Fernandes Francisco , Engelen Aschwin H. , Airoldi Laura , Serrão Ester A. 
Published: December 2016

AbstractEffective predictive and management approaches for species occurring in a metapopulation structure require good understanding of interpopulation connectivity. In this study, we ask whether population genetic structure of marine species with fragmented distributions can be predicted by stepping‐stone oceanographic transport and habitat continuity, using as model an ecosystem‐structuring brown alga, Cystoseira amentacea var. stricta. To answer this question, we analysed the genetic structure and estimated the connectivity of populations along discontinuous rocky habitat patches in southern Italy, using microsatellite markers at multiple scales. In addition, we modelled the effect of rocky habitat continuity and ocean circulation on gene flow by simulating Lagrangian particle dispersal based on ocean surface currents allowing multigenerational stepping‐stone dynamics. Populations were highly differentiated, at scales from few metres up to thousands of kilometres. The best possible model fit to explain the genetic results combined current direction, rocky habitat extension and distance along the coast among rocky sites. We conclude that a combination of variable suitable habitat and oceanographic transport is a useful predictor of genetic structure. This relationship provides insight into the mechanisms of dispersal and the role of life‐history traits. Our results highlight the importance of spatially explicit modelling of stepping‐stone dynamics and oceanographic directional transport coupled with habitat suitability, to better describe and predict marine population structure and differentiation. This study also suggests the appropriate spatial scales for the conservation, restoration and management of species that are increasingly affected by habitat modifications.
Why UV vision and red vision are important for damselfish (Pomacentridae): structural and expression variation in opsin genes
Authors: Stieb Sara M. , Cortesi Fabio , Sueess Lorenz , Carleton Karen L. , Salzburger Walter , Marshall N. J. 
Published: December 2016

AbstractCoral reefs belong to the most diverse ecosystems on our planet. The diversity in coloration and lifestyles of coral reef fishes makes them a particularly promising system to study the role of visual communication and adaptation. Here, we investigated the evolution of visual pigment genes (opsins) in damselfish (Pomacentridae) and examined whether structural and expression variation of opsins can be linked to ecology. Using DNA sequence data of a phylogenetically representative set of 31 damselfish species, we show that all but one visual opsin are evolving under positive selection. In addition, selection on opsin tuning sites, including cases of divergent, parallel, convergent and reversed evolution, has been strong throughout the radiation of damselfish, emphasizing the importance of visual tuning for this group. The highest functional variation in opsin protein sequences was observed in the short‐ followed by the long‐wavelength end of the visual spectrum. Comparative gene expression analyses of a subset of the same species revealed that with SWS1, RH2B and RH2A always being expressed, damselfish use an overall short‐wavelength shifted expression profile. Interestingly, not only did all species express SWS1 – a UV‐sensitive opsin – and possess UV‐transmitting lenses, most species also feature UV‐reflective body parts. This suggests that damsels might benefit from a close‐range UV‐based ‘private’ communication channel, which is likely to be hidden from ‘UV‐blind’ predators. Finally, we found that LWS expression is highly correlated to feeding strategy in damsels with herbivorous feeders having an increased LWS expression, possibly enhancing the detection of benthic algae.
The metalloprotease SepA governs processing of accumulation‐associated protein and shapes intercellular adhesive surface properties in Staphylococcus epidermidis
Authors: Paharik Alexandra E. , Kotasinska Marta , Both Anna , Hoang Tra‐My N. , Büttner Henning , Roy Paroma , Fey Paul D. , Horswill Alexander R. , Rohde Holger 
Published: December 2016

SummaryThe otherwise harmless skin inhabitant Staphylococcus epidermidis is a major cause of healthcare‐associated medical device infections. The species' selective pathogenic potential depends on its production of surface adherent biofilms. The Cell wall‐anchored protein Aap promotes biofilm formation in S. epidermidis, independently from the polysaccharide intercellular adhesin PIA. Aap requires proteolytic cleavage to act as an intercellular adhesin. Whether and which staphylococcal proteases account for Aap processing is yet unknown. Here, evidence is provided that in PIA‐negative S. epidermidis 1457Δica, the metalloprotease SepA is required for Aap‐dependent S. epidermidis biofilm formation in static and dynamic biofilm models. qRT‐PCR and protease activity assays demonstrated that under standard growth conditions, sepA is repressed by the global regulator SarA. Inactivation of sarA increased SepA production, and in turn augmented biofilm formation. Genetic and biochemical analyses demonstrated that SepA‐related induction of biofilm accumulation resulted from enhanced Aap processing. Studies using recombinant proteins demonstrated that SepA is able to cleave the A domain of Aap at residue 335 and between the A and B domains at residue 601. This study identifies the mechanism behind Aap‐mediated biofilm maturation, and also demonstrates a novel role for a secreted staphylococcal protease as a requirement for the development of a biofilm.
Metabolic adaptation of Chlamydia trachomatis to mammalian host cells
Authors: Mehlitz Adrian , Eylert Eva , Huber Claudia , Lindner Buko , Vollmuth Nadine , Karunakaran Karthika , Goebel Werner , Eisenreich Wolfgang , Rudel Thomas 
Published: December 2016

SummaryMetabolic adaptation is a key feature for the virulence of pathogenic intracellular bacteria. Nevertheless, little is known about the pathways in adapting the bacterial metabolism to multiple carbon sources available from the host cell. To analyze the metabolic adaptation of the obligate intracellular human pathogen Chlamydia trachomatis, we labeled infected HeLa or Caco‐2 cells with 13C‐marked glucose, glutamine, malate or a mix of amino acids as tracers. Comparative GC‐MS‐based isotopologue analysis of protein‐derived amino acids from the host cell and the bacterial fraction showed that C. trachomatis efficiently imported amino acids from the host cell for protein biosynthesis. FT‐ICR‐MS analyses also demonstrated that label from exogenous 13C‐glucose was efficiently shuffled into chlamydial lipopolysaccharide probably via glucose 6‐phosphate of the host cell. Minor fractions of bacterial Ala, Asp, and Glu were made de novo probably using dicarboxylates from the citrate cycle of the host cell. Indeed, exogenous 13C‐malate was efficiently taken up by C. trachomatis and metabolized into fumarate and succinate when the bacteria were kept in axenic medium containing the malate tracer. Together, the data indicate co‐substrate usage of intracellular C. trachomatis in a stream‐lined bipartite metabolism with host cell‐supplied amino acids for protein biosynthesis, host cell‐provided glucose 6‐phosphate for cell wall biosynthesis, and, to some extent, one or more host cell‐derived dicarboxylates, e.g. malate, feeding the partial TCA cycle of the bacterium. The latter flux could also support the biosynthesis of meso‐2,6‐diaminopimelate required for the formation of chlamydial peptidoglycan.
Structural mechanism for bacterial oxidation of oceanic trimethylamine into trimethylamine N‐oxide
Authors: Li Chun‐Yang , Chen Xiu‐Lan , Zhang Dian , Wang Peng , Sheng Qi , Peng Ming , Xie Bin‐Bin , Qin Qi‐Long , Li Ping‐Yi , Zhang Xi‐Ying , Su Hai‐Nan , Song Xiao‐Yan , Shi Mei , Zhou Bai‐Cheng , Xun Lu‐Ying , Chen Yin , Zhang Yu‐Zhong 
Published: December 2016

SummaryTrimethylamine (TMA) and trimethylamine N‐oxide (TMAO) are widespread in the ocean and are important nitrogen source for bacteria. TMA monooxygenase (Tmm), a bacterial flavin‐containing monooxygenase (FMO), is found widespread in marine bacteria and is responsible for converting TMA to TMAO. However, the molecular mechanism of TMA oxygenation by Tmm has not been explained. Here, we determined the crystal structures of two reaction intermediates of a marine bacterial Tmm (RnTmm) and elucidated the catalytic mechanism of TMA oxidation by RnTmm. The catalytic process of Tmm consists of a reductive half‐reaction and an oxidative half‐reaction. In the reductive half‐reaction, FAD is reduced and a C4a‐hydroperoxyflavin intermediate forms. In the oxidative half‐reaction, this intermediate attracts TMA through electronic interactions. After TMA binding, NADP+ bends and interacts with D317, shutting off the entrance to create a protected micro‐environment for catalysis and exposing C4a‐hydroperoxyflavin to TMA for oxidation. Sequence analysis suggests that the proposed catalytic mechanism is common for bacterial Tmms. These findings reveal the catalytic process of TMA oxidation by marine bacterial Tmm and first show that NADP+ undergoes a conformational change in the oxidative half‐reaction of FMOs.
Elucidating the role of hyposalivation and autoimmunity in oral candidiasis
Authors: Billings M , Dye BA , Iafolla T , Grisius M , Alevizos I 
Published: December 2016

IntroductionOral candidiasis (OC) is a potential oral complication in Sjögren's syndrome (SS). Some studies indicate that the low stimulated salivary flow and not low unstimulated salivary flow is associated with OC in SS, while others report that the underlying autoimmune disorders contribute to OC, based solely on correlation coefficients. Given the conflicting and limited existing evidence, we purposed to ascertain the role of both salivary gland dysfunction (hyposalivation based on unstimulated and stimulated flow rates) and autoimmunity (SS, other autoimmune disorders) in OC among those with SS, other salivary gland dysfunction, and non‐salivary gland dysfunction controls (NSGD).MethodsA nested case–control study was designed within a larger NIH/NIDCR cohort. Descriptive analyses, nonparametric tests, comparative analyses, and multivariate logistic regression analyses were undertaken.ResultsData on 1526 subjects (701 SS, 247 ISS, 355 Sicca, and 223 NSGD) were obtained from the source cohort of 2046 and analyzed for this study. The median whole unstimulated salivary flow rate (WUS, ml 15 min−1) was lower in SS (0.8, interquartile range (IQR) 1.8) compared to ISS (5.5, IQR: 5.2, P < 0.001) and NSGD (3.8, IQR: 3.8, P < 0.001) but comparable with that of Sicca (1.0, IQR: 1.5, P = 0.777) participants. The median total stimulated salivary flow rate (TSS, ml 15 min−1) was lowest in SS (7.0, IQR: 12.4, P < 0.001) compared to other groups. Of the 45 OC cases in this cohort, 71.1% (n = 32) were from the SS group. The prevalence of OC was highest in the SS group (4.6%, P = 0.008). SS group had twice the risk of OC than NSGD (OR = 2.2, 95%CI: 1.1–4.2, P = 0.02) and Sicca (OR = 2.2, 95% CI: 1.0–4.8, P = 0.03), adjusting for confounders; hyposalivation [WUS (OR = 5.1, 95%CI: 2.5–10.4, P < 0.001), TSS (OR = 1.9, 95%CI: 1.0–3.5, P = 0.04)], history of other autoimmune disorders (OR = 4.4, 95%CI: 1.7–11.3, P = 0.002), medications for extraglandular manifestations (OR = 2.3, 95%CI: 1.1–4.9, P = 0.03), and diabetes mellitus (4.2, 95%CI: 1.2–15.2, P = 0.02) were independent predictors of OC; females had a lower risk than males (OR = 0.29, 95%CI: 0.13–0.67, P = 0.004). Age, race, anti‐SSA/SSB autoantibodies, focus score, other medications, anxiety, fatigue, cigarette smoking, alcohol, and caffeine use were not associated with oral candidiasis.ConclusionSalivary gland dysfunction (hyposalivation with WUS being a stronger predictor than TSS) and autoimmunity (SS, other autoimmune disorders, medications, i.e., DMARDS) are both independent predictors of OC. Diabetes mellitus is an independent predictor of OC among those with salivary gland dysfunction. Our findings suggest that these independent predictors should be considered in the prevention and management of OC in this population.
Active Atrial Function and Atrial Scar Burden After Multiple Catheter Ablations of Persistent Atrial Fibrillation
Authors: NÜHRICH JANA M. , GEISLER ANNE C. , STEVEN DANIEL , HOFFMANN BORIS A. , SCHÄFFER BENJAMIN , LUND GUNNAR , STEHNING CHRISTIAN , RADUNSKI ULF K. , SULTAN ARIAN , SCHWARZL MICHAEL , ADAM GERHARD , WILLEMS STEPHAN , MUELLERLEILE KAI 
Published: December 2016

BackgroundExtensive and repeated substrate modification (SM) is frequently performed as an ablation strategy in persistent atrial fibrillation (persAF). The effect of these extended ablation strategies on atrial function has not been investigated sufficiently so far. The purpose was to assess atrial function by cardiac magnetic resonance (CMR) and its association with left atrial (LA) scar burden by electroanatomical voltage‐mapping after multiple persAF ablation procedures.MethodsWe included 16 persAF patients who had ≥2 SM procedures and a control group (CG) of 21 persAF patients without prior ablation. CMR was performed in sinus rhythm at least 4 weeks after the last cardioversion. Active left and right (RA) atrial emptying fractions (AEF) as well as peak active left atrial appendage (LAA) emptying velocities were obtained by CMR flow measurements. Furthermore, LA scar burden was quantified on electroanatomical voltage maps by the portion of points with local voltage amplitude <0.2 mV.ResultsWe found median LA‐AEF to be lower (13 [9–22] vs 32 [26–36] %, P < 0.001) and median LA scar burden to be higher (40 [20–68] vs nine [3–18] %, P < 0.05) in the SM group compared with the CG. Furthermore, a significant correlation was found between mean LA voltage and LA‐AEF (r2 = 0.62, P < 0.001). No significant differences were detected with respect to median RA‐AEF (41 [28–48] vs 47 [35–50] %, P = 0.43) and median peak LAA emptying velocities (30 [16–40] vs 17 [13–28] cm/s, P = 0.07).ConclusionsActive LA function is preserved but significantly impaired and associated with ablation‐related LA scar burden after multiple extensive persAF ablations.