bluuebunny/crossref_metadata_2025 huggingface dataset:
Transfection reagent Lipofectamine triggers type I interferon signaling activation in macrophages
Authors: Guo Xiaomin , Wang Huan , Li Yang , Leng Xiaopeng , Huang Weiwei , Ma Yanbing , Xu Tao , Qi Xiaopeng
Published: August 2018

The commercial transfection reagent Lipofectamine has been widely used for cytoplasmic delivery of nucleic acids and for cytosolic engagement with intracellular innate immune sensors to trigger type I interferon (IFN) production. However, the effect of Lipofectamine alone on type I IFN response has not been studied in detail. Here, we show that Lipofectamine induced type I IFN signaling in both RAW 264.7 macrophage‐like cells and primary bone marrow‐derived macrophages. Type I IFN induction was dependent on interferon regulatory factor (IRF)3 and IRF7 and partially required the toll/interleukin‐1 receptor‐domain‐containing adapter‐inducing interferon‐β. In contrast, the transfection reagent Xfect did not activate type I IFN signaling. Our study highlights the potential confounding experimental interpretation when using Lipofectamine‐based transfection for delivering intracellular ligands and provides important insights into lipid signaling in innate immune responses.
Copepod diapause and the biogeography of the marine lipidscape
Authors: Record Nicholas R. , Ji Rubao , Maps Frédéric , Varpe Øystein , Runge Jeffrey A. , Petrik Colleen M. , Johns David
Published: August 2018

Aim

One of the primary characteristics that determines the structure and function of marine food webs is the utilization and prominence of energy‐rich lipids. The biogeographical pattern of lipids throughout the ocean delineates the marine “lipidscape,” which supports lipid‐rich fish, mammal, and seabird communities. While the importance of lipids is well appreciated, there are no synoptic measurements or biogeographical estimates of the marine lipidscape. Productive lipid‐rich food webs in the pelagic ocean depend on the critical diapause stage of large pelagic copepods, which integrate lipid production from phytoplankton, concentrating it in space and time, and making it available to upper trophic levels as particularly energy‐rich wax esters. As an important first step towards mapping the marine lipidscape, we compared four different modelling approaches of copepodid diapause, each representing different underlying hypotheses, and evaluated them against global datasets.

Location

Global Ocean.

Taxon

Copepoda.

Methods

Through a series of global model runs and data comparisons, we demonstrated the potential for regional studies to be extended to estimate global biogeographical patterns of diapause. We compared four modelling approaches each designed from a different perspective: life history, physiology, trait‐based community ecology, and empirical relationships. We compared the resulting biogeographical patterns and evaluated the model results against global measurements of copepodid diapause.

Results

Models were able to resolve more than just the latitudinal pattern of diapause (i.e. increased diapause prevalence near the poles), but to also pick up a diversity of regions where diapause occurs, such as coastal upwelling zones and seasonal seas. The life history model provided the best match to global observations. The predicted global biogeographical patterns, combined with carbon flux estimates, suggested a lower bound of 0.031–0.25 Pg C yr−1 of downward flux associated with copepodid diapause.

Main conclusions

Results indicated a promising path forward for representing a detailed biogeography of the marine lipidscape and its associated carbon flux in global ecosystem and climate models. While complex models may offer advantages in terms of reproducing details of community structure, simpler theoretically based models appeared to best reproduce broad‐scale biogeographical patterns and showed the best correlation with observed biogeographical patterns.
The effect of periodontal therapy on oxidative stress biomarkers: A systematic review
Authors: da Silva Júlia Christ , Muniz Francisco Wilker Mustafa Gomes , Oballe Harry Juan Rivera , Andrades Michael , Rösing Cassiano Kuchenbecker , Cavagni Juliano
Published: August 2018

Aim

To systematically review the literature about the effect of periodontal treatment on oxidative stress (OxS) biomarkers.

Material and Methods

Three databases (PubMed, EMBASE, and Scopus) were searched up to February 2018. Clinical trials with a follow‐up of at least 6 weeks after mechanical periodontal treatment were included. Due to the high heterogeneity among the units and indices of measurements used in the studies, a meta‐analysis was not performed.

Results

Overall, 3,199 studies were retrieved, of which 20 were included. Four studies were randomized clinical trials (RCT), and 16 studies were non‐RCTs. The most common OxS biomarkers used were 8‐hydroxydeoxiguanosine (8‐OHdG), total oxidant status (TOS), and total antioxidant status (TAS). After treatment, most of the studies reported a decrease in 8‐OHdG concentration in the gingival crevicular fluid (GCF) and saliva. In addition, the salivary concentration of this biomarker was similar to periodontally healthy patients. Periodontal therapy was effective in reducing TOS in GCF, saliva, and serum in most studies. TAS, however, responded inconsistently to the periodontal intervention.

Conclusion

Periodontal therapy reduces the levels of OxS biomarkers, even to values similar to those found in periodontally healthy individuals. Additional RCTs are warranted, as the information is mainly based on nonrandomized studies.
Effects of Bifidobacterium probiotic on the treatment of chronic periodontitis: A randomized clinical trial
Authors: Invernici Marcos M. , Salvador Sérgio L. , Silva Pedro H. F. , Soares Mariana S. M. , Casarin Renato , Palioto Daniela B. , Souza Sérgio L. S. , Taba Mario , Novaes Arthur B. , Furlaneto Flávia A. C. , Messora Michel R.
Published: August 2018

Aim

This randomized placebo‐controlled clinical trial evaluated the effect of Bifidobacterium animalis subsp. lactis (B. lactis) HN019‐containing probiotic lozenges as adjuvant to scaling and root planing (SRP) in patients with generalized chronic periodontitis.

Materials and Methods

Forty‐one chronic periodontitis patients were recruited and monitored clinically, immunologically, and microbiologically at baseline (before SRP) and 30 and 90 days after SRP. All patients were randomly assigned to a Test (SRP + Probiotic, n = 20) or Control (SRP + Placebo, n = 21) group. The probiotic lozenges were used twice a day for 30 days. The data were statistically analysed.

Results

The Test group presented a decrease in probing pocket depth and a clinical attachment gain significantly higher than those of the Control group at 90 days. The Test group also demonstrated significantly fewer periodontal pathogens of red and orange complexes, as well as lower proinflammatory cytokine levels when compared to the Control group. Only the Test group showed an increase in the number of B. lactis HN019 DNA copies on subgingival biofilm at 30 and 90 days.

Conclusion

The use of B. lactis HN019 as an adjunct to SRP promotes additional clinical, microbiological, and immunological benefits in the treatment of chronic periodontitis (NCT03408548).
The effect of milk consumption on acne: a meta‐analysis of observational studies
Authors: Dai R. , Hua W. , Chen W. , Xiong L. , Li L.
Published: August 2018

Background

Acne is a common skin condition in developed countries with western diets. The effect of milk on acne has been highly controversial. To examine the association between milk consumption and acne risk, we conducted a meta‐analysis of available data.

Materials and Methods

We carried out comprehensive databases search of PubMed, Embase, Medline and Cochrane Library and identified four cohort studies and nine case–control or cross‐sectional studies, including a total of 71 819 participants. We evaluated the pooled odds ratio (OR) with its 95% confidence interval (CI) using a random effects model. Subgroup analyses on acne severity, milk forms and milk intake levels were performed.

Results

Compared with non‐consumers, the pooled OR was 1.16 (95% CI 1.09–1.24) for overall milk consumers in all included studies, and 1.17 (95% CI 1.10–1.24) in cohort studies and 1.16 (95% CI 1.09–1.24) in case–control or cross‐sectional studies. Subgroup analysis on milk forms determined a stronger association in skim milk consumers (OR = 1.24, 95% CI 1.13–1.37) than in low‐fat consumers (OR = 1.14, 95% CI 1.08–1.22) and full‐fat consumers (OR = 1.13, 95% CI 1.05–1.21). The pooled OR was greater for high intake level of milk (OR = 1.12, 95% CI 1.01–1.24) than medium intake level of milk (OR = 1.08, 95% CI 1.00–1.17). A subset study of moderate‐to‐severe acne also found a positive association with milk consumption (OR 1.18, 95% CI 1.01–1.37), while no statistically significant association was found between mild acne risk and milk consumption (OR 1.14, 95% CI 0.86–1.51).

Conclusion

This meta‐analysis provides evidence of a positive association between milk consumption and acne risk.
Resources mediate selection on module longevity in the field
Authors: Svanfeldt Karin , Monro Keyne , Marshall Dustin J.
Published: August 2018

The life histories of modular organisms are complicated, where selection and optimization can occur at both organismal and modular levels. At a modular level, growth, reproduction and death can occur in one module, independently of others. Across modular groups, there are no formal investigations of selection on module longevity. We used two field experiments to test whether selection acts on module longevity in a sessile marine invertebrate and whether selection varies across successional gradients and resource regimes. We found that selection does act on module longevity and that the strength of selection varies with environmental conditions. In environments where interspecific competition is high, selection favours colonies with longer zooid (module) longevity for colonies that initially received high levels of maternal investment. In environments where food availability is high and flow rate is low, selection also favours colonies with longer zooid longevity. These patterns of selection provide partial support for module longevity theory developed for plants. Nevertheless, that selection on module longevity is so context‐dependent suggests that variation in module longevity is likely to be maintained in this system.
Rethinking bias and truth in evidence‐based health care
Authors: Wieringa Sietse , Engebretsen Eivind , Heggen Kristin , Greenhalgh Trish
Published: August 2018

In modern philosophy, the concept of truth has been problematized from different angles, yet in evidence‐based health care (EBHC), it continues to operate hidden and almost undisputed through the linked concept of “bias.” To prevent unwarranted relativism and make better inferences in clinical practice, clinicians may benefit from a closer analysis of existing assumptions about truth, validity, and reality.

In this paper, we give a brief overview of several important theories of truth, notably the ideal limit theorem (which assumes an ultimate and absolute truth towards which scientific inquiry progresses), the dominant way truth is conceptualized in the discourse and practice of EBHC.

We draw on Belgian philosopher Isabelle Stengers' work to demonstrate that bias means one thing if one assumes a world of hard facts “out there,” waiting to be collected. It means something different if one takes a critical view of the knowledge‐power complex in research trials. Bias appears to have both an unproductive aspect and a productive aspect as argued by Stengers and others: Facts are not absolute but result from an interest, or interesse: a bias towards a certain line of questioning that cannot be eliminated.

The duality that Stengers' view invokes draws attention to and challenges the assumptions underlying the ideal limit theory of truth in several ways. Most importantly, it casts doubt on the ideal limit theory as it applies to the single case scenario of the clinical encounter, the cornerstone of EBHC. To the extent that the goal of EBHC is to support inferencing in the clinical encounter, then the ideal limit as the sole concept of truth appears to be conceptually insufficient. We contend that EBHC could usefully incorporate a more pluralist understanding of truth and bias and provide an example how this would work out in a clinical scenario.
Vertical bone augmentation in a single‐tooth gap with an allogenic bone ring: Clinical considerations
Authors: Giesenhagen Bernhard , Martin Nathalie , Donkiewicz Phil , Perić Kačarević Željka , Smeets Ralf , Jung Ole , Schnettler Reinhard , Barbeck Mike
Published: August 2018

Objective

The main objective of this case report is to introduce a one‐stage bone block augmentation with a cylindrical freeze‐dried bone allograft (FDBA) and simultaneous implantation for the reconstruction of a single‐tooth bone defect.

Clinical Considerations

The report describes this method on the basis of radiographical and clinical images derived from a single patient.

Conclusions

The report demonstrates the time‐saving and successful application of this treatment concept, which has the potential to increase patient satisfaction and comfort.

Clinical Significance

The application of the presented technique enabled a prosthetic rehabilitation of the extracted tooth about 3 months earlier as compared to the conventional procedure, while demonstrating no compromises regarding clinical outcome, functionality and esthetics.
Impacted teeth: Closed flap surgery
Authors: Nowzari Hessam , Rodriguez Angel Emmanuel
Published: August 2018

Objective

The present pilot study evaluated the impact of closed flap surgical technique on periodontal tissues and the esthetic outcome.

Materials and Methods

Twenty‐four consecutively treated patients with a mean age of 15 (range 12‐30) underwent closed flap surgery for the exposure of impacted teeth. The study evaluated periodontal probing depths, bone level, zone of keratinized tissue, and esthetic appearance after the completion of orthodontic treatment.

Results

Tooth impaction was more frequent in females (No. 14) than males (No. 10) in this study. Palatal and buccal impactions were 77% and 23%, respectively. Post‐orthodontic treatment, periodontal probing depth averaged 2.2 mm and zone of keratinized gingiva averaged 3.6 mm. No discernible radiographic bone loss or root resorption was noticed. Overall, gingival margins provided an esthetic appearance in all cases.

Conclusion

Closed flap surgical technique was associated with periodontal health and esthetic outcomes for an average of 10 years post‐orthodontic treatment.

Clinical Significance

The evolution of teeth and maxillary/mandibular bones has distinctively differed in origins and development contributing to tooth impaction and overcrowding. This study demonstrated that closed flap surgery is a reliable procedure for the treatment of impacted teeth that provides periodontal health and esthetic appearance post‐orthodontic treatment.
Multilocus sequence analysis revealed a high genotypic diversity of Aeromonas hydrophila infecting fish in Uganda
Authors: Wamala Samuel Posian , Mugimba Kizito Kahoza , Dubey Saurabh , Takele Abayneh , Munang'andu Hetron Mweemba , Evensen Øystein , Mutoloki Stephen , Byarugaba Denis Karuhize , Sørum Henning
Published: August 2018

A multilocus sequence analysis (MLSA) was carried out to delineate Aeromonas hydrophila from fish in Uganda. Five housekeeping genes including recA, gyrB, metG, gltA and pps; and the 16S rRNA gene were amplified and sequenced from a total of nine A. hydrophila isolates. The obtained sequences were edited, and consensus sequences generated for each gene locus. The housekeeping gene sequences were concatenated and phylogenetic analysis performed in MEGA version 7.0.2. Pairwise distances ranged from 0.000 to 0.118, highest within the gltA gene locus and lowest within the 16S rRNA gene. The average evolutionary diversity within isolates from the same source ranged between 0.002 and 0.037, and it was 0.033 between the different sources. Similar tree topologies were obtained from the different gene loci with recA, metG and gyrB being more consistent in discriminating isolates according to sources while the 16S rRNA gene had the lowest resolution. The concatenated tree had the highest discriminatory power. This study revealed that A. hydrophila strains infecting fish in Uganda are of diverse genotypes suggesting different sources of infection in a given outbreak. Efforts to minimize spread of the bacteria across sources should be emphasized to control infections of mixed genotypes.
Age‐dependent changes of the mandible bone throughout the lifespan in female F344/N rat
Authors: Nishijima Kazutoshi , Ohno Tamio , Saito Ryoichi , Sumi Yasunori , Aoyama Hiroaki , Tanaka Shin
Published: August 2018

Age‐dependent changes of the mandible bone in female F344/N rats, aged 22–1196 days, were analyzed using physiological bone properties and morphology. Bone weight, bone area, bone mineral components, and bone mineral density were assessed using dual‐energy X‐ray absorptiometry. The bone weight, bone area, bone mineral components, and bone mineral density increased rapidly until approximately 150 days of age, increased gradually thereafter, and then stabilized or decreased after 910 days of age. The ratio of bone mineral components to bone weight (bone mineral ratio) increased rapidly until approximately 43 days of age and stabilized thereafter. Size of the mandible, which was measured at 13 points on mandible surface, increased with age, and the rate of change showed a similar pattern to the other parameters. From a principal component analysis on morphometric measurements, principal component 1 (size factor) increased proportionally with age, whereas principal component 2 (shape factor) decreased until approximately 88 days of age and then increased after 365 days of age. As a result, the scatter plots for principal component 1 and principal component 2 were V‐shaped, which indicates that the mandible developed in size, with deformation at younger ages, and recovered its original shape later in life. Our results revealed the occurrence of inflection points at approximately 43, 88, 150, 365, and 910 days of age. Some of these ages corresponded to transition points revealed by the age‐dependent changes of the occlusal mandibular condyle and tooth wear in the same rat.
Ultrasound to improve the safety of hyaluronic acid filler treatments
Authors: Schelke Leonie W. , Decates Tom S. , Velthuis Peter J.
Published: August 2018

Background

Hyaluronic acid fillers are known for a reliable safety profile, but complications do occur, even serious vascular adverse events.

Objective

To improve the safety of hyaluronic acid filler treatments.

Methods

Ultrasound is used to image hyaluronic acid fillers.

Results

Before a filler treatment is performed with ultrasound, previous filler treatments can be brought in to sight and vascular mapping can be performed. In case of adverse events, the filler and the surrounding tissues are visible. Dislocation, abscesses, and vascular adverse events can be seen. Under ultrasound guidance, hyaluronidase can be injected directly into the filler deposit.

Conclusion

Ultrasound examination can be an important tool to improve the safety of hyaluronic acid filler treatments.
Antera 3D camera: A novel method for evaluating the therapeutic efficacy of fractional CO2 laser for surgical incision scars
Authors: Zhang Nan , Shi Kai , Hong Lei , Zhao Jingchun , Yu Jiaao
Published: August 2018

Objective

To introduce a novel method for evaluating the therapeutic efficacy of fractional CO2 laser for incision scars.

Methods

A total of 72 patients after incision healing for at least 2 years were included in the series, with scars on neck, thyroid, chest, and limb from September 2013 to September 2016. The image of scar was taken by Antrea 3D camera before the treatment, VSS, and UN4P were also applied for scar evaluation. A total of four sessions at 4‐6 intervals were conducted to each patient. After 3 months of last session, a final assessment was carried out by Antera 3D and VSS, UN4P independently.

Results

The Antera scores for color after 4 sessions were 8.78 ± 2.11, which were significantly lower than the prior treatment (9.62 ± 1.90, t = 2.51, P < 0.05). The Antera scores for texture after four sessions were 22.80 ± 5.23, which was significantly lower than the prior treatment (30.33 ± 5.41, t = 8.48, P < 0.05). The Antera scores for melanin levels after four sessions were 0.52 ± 0.05, which was significantly lower than the prior treatment (0.54 ± 0.05, t = 2.4, P < 0.05). The Antera scores for hemoglobin levels after four sessions were 1.88 ± 0.50, which was significantly lower than the prior treatment (2.11 ± 0.45, t = 2.90, P < 0.05). The Vancouver Scar scores after four sessions were 7.1 ± 2.0, which showed no statistically significant differences with the prior treatment (7.5 ± 2.4, t = 1.09, P = 0.25 > 0.05). The University of North Carolina "4P" Scar scores after four sessions were 6.6 ± 1.5, which also showed no statistically significant differences with the prior treatment (7.0 ± 1.9, t = 1.40, P = 0.15 > 0.05).

Conclusions

For scar therapeutic evaluation, Antera 3D camera is objective and accurate, and is worthy of wide promotion.
Prognostic impact of combined immunoprofiles in oropharyngeal squamous cell carcinoma patients with respect to AJCC 8th edition
Authors: Gurin Dominik , Slavik Marek , Hermanova Marketa , Shatokhina Tetiana , Sana Jiri , Kazda Tomas , Selingerova Iveta , Ahmad Parwez , Smilek Pavel , Horakova Zuzana , Hendrych Michal , Slampa Pavel , Slaby Ondrej
Published: August 2018

Objectives

To examine combined immunoprofiles of epidermal growth factor receptor (EGFR), CD44, and p16 in oropharyngeal squamous cell carcinoma (OPSCC) and to correlate them with radiotherapy treatment outcomes and clinicopathological parameters. Prognostic impact of the American Joint Committee on Cancer (AJCC) 8th edition staging system in comparison with 7th edition was analyzed.

Methods

The study included 77 OPSCC patients treated by definitive intensity‐modulated radiotherapy (IMRT). Clinical staging was assessed according to the AJCC, both 7th and 8th edition. Immunohistochemical (IHC) analysis of CD44 and EGFR was performed on primary biopsy tumor tissues. To evaluate the HPV status, IHC detection of p16 was employed.

Results

The AJCC 8th edition staging system revealed correlations between overall survival (OS), progression‐free survival (PFS), locoregional control (LRC), and clinical stage. EGFR and CD44 positivity (+) and p16 negativity (−) were associated with clinical stage IV of the disease. CD44+ and EGFR+ OPSCC displayed worse OS and LRC, and these cases also showed the worst 3‐year OS and LRC. Combined analysis of protein expressions identified an association between p16− and EGFR+, p16− and CD44+, EGFR+, and CD44+. Combined immunoprofiles CD44+/p16−, EGFR+/p16−, and EGFR+/CD44+ were associated with worst OS and LRC.

Conclusions

Combined immunoprofiles of p16, EGFR, and CD44 might provide valuable prognostic and predictive information for the individual OPSCC patients, especially in terms of response to IMRT and prediction of treatment outcomes. Application of the AJCC 8th edition staging for HPV+ OPSCC proved to improve hazard discrimination and prognostication of OPSCC.
Small intestinal epithelial permeability to water‐soluble nutrients higher in passerine birds than in rodents
Authors: Garro Cintia , Brun Antonio , Karasov William H. , Caviedes‐Vidal Enrique
Published: August 2018

In the small intestine transcellular and paracellular pathways are implicated in water‐soluble nutrient absorption. In small birds the paracellular pathway is quantitatively important while transcellular pathway is much more important in terrestrial mammals. However, there is not a clear understanding of the mechanistic underpinnings of the differences among taxa. This study was aimed to test the hypothesis that paracellular permeability in perfused intestinal segments is higher in passerine birds than rodents. We performed in situ intestinal perfusions on individuals of three species of passerine birds(Passer domesticus,Taeniopygia guttataandFurnarius rufus) and two species of rodents (Mus musculusandMeriones ungiculatus). Using radio‐labelled molecules, we measured the uptake of two nutrients absorbed by paracellular and transcellular pathways (L‐proline and 3–O–methyl–D‐glucose) and one carbohydrate that has no mediated transport (L‐arabinose). Birds exhibited ~2 to ~3 times higher L‐arabinose clearance per cm2epithelium than rodents. Moreover, paracellular absorption accounted for proportionally more of 3–O–methyl–D‐glucose and L‐proline absorption in birds than in rodents. These differences could be explained by differences in intestinal permeability and not by other factors such as increased retention time or higher intestinal nominal surface area. Furthermore, analysis of our results and all other existing data on birds, bats and rodents shows that insectivorous species (one bird, two bats and a rodent) had only 30% of the clearance of L‐arabinose of non‐insectivorous species. This result may be explained by weaker natural selection for high paracellular permeability in animal‐ than in plant‐consumers. Animal‐consumers absorb less sugar and more amino acids, whose smaller molecular size allow them to traverse the paracellular pathway more extensively and faster than glucose.
Effect of immune modulators on in vitro activation and proliferation of peripheral blood mononuclear cells from multiparous Holstein cows peripartum
Authors: Wang Shaopu , Meese Susanne , Ulbrich Susanne E. , Bollwein Heinrich , Röntgen Monika , Gimsa Ulrike , Schwarm Angela
Published: August 2018

This in vitro study examined the ability of important immune modulators [β‐hydroxybutyrate (BHB), cortisol, prolactin, isoproterenol and insulin] to influence the responsiveness of peripheral blood mononuclear cells (PBMC) from multiparous dairy cows 29 ± 2 days before and 14 ± 3 days after calving. The activation and proliferation of PBMC in response to the mitogen phytohemagglutinin was estimated by the oxygen consumption rate after 24 hr and the MTT (3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5diphenyl tetrazolium bromide) method after 72 hr respectively. In early lactation, the presence of 2 compared to 0.5 mmol/L BHB reduced PBMC activation (p < 0.05) and proliferation (p < 0.10), and the presence of 0.7 compared to 0.2 ng/ml insulin enhanced (p < 0.10) PBMC proliferation. In dry cows, the presence of low concentrations of BHB and insulin and both concentrations of prolactin (20 vs. 300 ng/ml) and isoproterenol (70 vs. 130 ng/L) enhanced activation (p < 0.10), but not proliferation (p ≥ 0.10) compared to cultures with no modulator addition. The presence or absence of high or low concentrations of hydrocortisone (20 vs. 45 nmol/L) did not (p ≥ 0.10) influence the activation and proliferation of PBMC from dry and early lactating cows. It is tempting to speculate that in antepartum PBMC the modulators represented an energy source or positive extrinsic signals to use nutrients for the activation process. On the other hand, PBMC from postpartum cows are known to be exposed to a metabolic challenging endocrine background. Under such conditions, high BHB concentrations and high insulin concentrations seem to act as negative and positive signals for PBMC, respectively, to utilize nutrients for activation and proliferation.
Fine‐scale geographic patterns of gene flow and reproductive character displacement inDrosophila subquinariaandDrosophila recens
Authors: Dyer Kelly A. , Bewick Emily R. , White Brooke E. , Bray Michael J. , Humphreys Devon P.
Published: August 2018

When two species are incompletely isolated, strengthening premating isolation barriers in response to the production of low fitness hybrids may complete the speciation process. Here, we use the sister speciesDrosophila subquinariaandDrosophila recensto study the conditions under which this reinforcement of species boundaries occurs in natural populations. We first extend the region of known sympatry between these species, and then we conduct a fine‐scale geographic survey of mate discrimination coupled with estimates of gene flow within and admixture between species. WithinD. subquinaria, reinforcement is extremely effective: we find variation in mate discrimination both againstD. recensmales and against conspecific allopatric males on the scale of a few kilometres and in the face of gene flow both from conspecific populations and introgression fromD. recens. InD. recens, we do not find evidence for increased mate discrimination in sympatry, even whereD. recensis rare, consistent with substantial gene flow throughout the species’ range. Finally, we find that introgression between species is asymmetric, with more fromD. recensintoD. subquinariathan vice versa. Within each species, admixture is highest in the geographic region where it is rare relative to the other species, suggesting that when hybrids are produced they are of low fitness. In sum, reinforcement withinD. subquinariais effective at maintaining species boundaries, but even when reinforcing selection is strong it may not always result in a pattern of strong reproductive character displacement due to variation in the frequency of hybridization and gene flow from neighbouring populations.
The sialic acid transporter NanT is necessary and sufficient for uptake of 3‐deoxy‐d‐manno‐oct‐2‐ulosonic acid (Kdo) and its azido analog in Escherichia coli
Authors: Nilsson Inga , Prathapam Ramadevi , Grove Kerri , Lapointe Guillaume , Six David A.
Published: August 2018

3‐Deoxy‐d‐manno‐oct‐2‐ulosonic acid (Kdo) is an essential component of lipopolysaccharides (LPS) in the Gram‐negative bacterial outer membrane. Metabolic labeling of Escherichia coli LPS with 8‐azido‐3,8‐dideoxy‐d‐manno‐oct‐2‐ulosonic acid (Kdo‐N3) has been reported but is inefficient. For optimization, it is important to understand how exogenous Kdo‐N3 enters the cytoplasm. Based on similarities between Kdo and sialic acids, we proposed and verified that the sialic acid transporter NanT imports exogenous Kdo‐N3 into E. coli. We demonstrated that E. coli ΔnanT were not labeled with Kdo‐N3, while expression of NanT in the ΔnanT mutant restored Kdo‐N3 incorporation. Induced NanT expression in a strain lacking Kdo biosynthesis led to higher exogenous Kdo incorporation and restoration of full‐length core‐LPS, suggesting that NanT also transports Kdo. While Kdo‐N3 incorporation was observed in strains having NanT, it was not detected in Pseudomonas aeruginosa and Acinetobacter baumannii, which lack nanT. However, heterologous expression of E. coli NanT in P. aeruginosa enabled Kdo‐N3 incorporation and labeling, though this led to abnormal morphology and growth arrest. NanT seems to define which bacteria can be labeled with Kdo‐N3, provides opportunities to enhance Kdo‐N3 labeling efficiency and spectrum, and raises the possibility of Kdo biosynthetic bypass where exogenous Kdo is present, perhaps even in vivo.
Feedback regulation of Caulobacter crescentus holdfast synthesis by flagellum assembly via the holdfast inhibitor HfiA
Authors: Berne Cécile , Ellison Courtney K. , Agarwal Radhika , Severin Geoffrey B. , Fiebig Aretha , Morton Robert I. , Waters Christopher M. , Brun Yves V.
Published: August 2018

To permanently attach to surfaces, Caulobacter crescentusproduces a strong adhesive, the holdfast. The timing of holdfast synthesis is developmentally regulated by cell cycle cues. When C. crescentusis grown in a complex medium, holdfast synthesis can also be stimulated by surface sensing, in which swarmer cells rapidly synthesize holdfast in direct response to surface contact. In contrast to growth in complex medium, here we show that when cells are grown in a defined medium, surface contact does not trigger holdfast synthesis. Moreover, we show that in a defined medium, flagellum synthesis and regulation of holdfast production are linked. In these conditions, mutants lacking a flagellum attach to surfaces over time more efficiently than either wild‐type strains or strains harboring a paralyzed flagellum. Enhanced adhesion in mutants lacking flagellar components is due to premature holdfast synthesis during the cell cycle and is regulated by the holdfast synthesis inhibitor HfiA. hfiA transcription is reduced in flagellar mutants and this reduction is modulated by the diguanylate cyclase developmental regulator PleD. We also show that, in contrast to previous predictions, flagella are not necessarily required for C. crescentus surface sensing in the absence of flow, and that arrest of flagellar rotation does not stimulate holdfast synthesis. Rather, our data support a model in which flagellum assembly feeds back to control holdfast synthesis via HfiA expression in a c‐di‐GMP‐dependent manner under defined nutrient conditions.
The eggplant AG91‐25 recognizes the Type III‐secreted effector RipAX2 to trigger resistance to bacterial wilt (Ralstonia solanacearum species complex)
Authors: Morel Arry , Guinard Jérémy , Lonjon Fabien , Sujeeun Lakshmi , Barberis Patrick , Genin Stéphane , Vailleau Fabienne , Daunay Marie‐Christine , Dintinger Jacques , Poussier Stéphane , Peeters Nemo , Wicker Emmanuel
Published: August 2018

To deploy durable plant resistance, we must understand its underlying molecular mechanisms. Type III effectors (T3Es) and their recognition play a central role in the interaction between bacterial pathogens and crops. We demonstrate that the Ralstonia solanacearum species complex (RSSC) T3E ripAX2 triggers specific resistance in eggplant AG91‐25, which carries the major resistance locus EBWR9. The eggplant accession AG91‐25 is resistant to the wild‐type R. pseudosolanacearum strain GMI1000, whereas a ripAX2 defective mutant of this strain can cause wilt. Notably, the addition of ripAX2 from GMI1000 to PSS4 suppresses wilt development, demonstrating that RipAX2 is an elicitor of AG91‐25 resistance. RipAX2 has been shown previously to induce effector‐triggered immunity (ETI) in the wild relative eggplant Solanum torvum, and its putative zinc (Zn)‐binding motif (HELIH) is critical for ETI. We show that, in our model, the HELIH motif is not necessary for ETI on AG91‐25 eggplant. The ripAX2 gene was present in 68.1% of 91 screened RSSC strains, but in only 31.1% of a 74‐genome collection comprising R. solanacearum and R. syzygii strains. Overall, it is preferentially associated with R. pseudosolanacearum phylotype I. RipAX2GMI1000 appears to be the dominant allele, prevalent in both R. pseudosolanacearum and R. solanacearum, suggesting that the deployment of AG91‐25 resistance could control efficiently bacterial wilt in the Asian, African and American tropics. This study advances the understanding of the interaction between RipAX2 and the resistance genes at the EBWR9 locus, and paves the way for both functional genetics and evolutionary analyses.
Role of the acquisition of a type 3 secretion system in the emergence of novel pathogenic strains of Xanthomonas
Authors: Meline Valérian , Delage Wesley , Brin Chrystelle , Li‐Marchetti Camille , Sochard Daniel , Arlat Matthieu , Rousseau Céline , Darrasse Armelle , Briand Martial , Lebreton Guillaume , Portier Perrine , Fischer‐Le Saux Marion , Durand Karine , Jacques Marie‐Agnès , Belin Etienne , Boureau Tristan
Published: August 2018

Cases of emergence of novel plant‐pathogenic strains are regularly reported that reduce the yields of crops and trees. However, the molecular mechanisms underlying such emergence are still poorly understood. The acquisition by environmental non‐pathogenic strains of novel virulence genes by horizontal gene transfer has been suggested as a driver for the emergence of novel pathogenic strains. In this study, we tested such an hypothesis by transferring a plasmid encoding the type 3 secretion system (T3SS) and four associated type 3 secreted proteins (T3SPs) to the non‐pathogenic strains of Xanthomonas CFBP 7698 and CFBP 7700, which lack genes encoding T3SS and any previously known T3SPs. The resulting strains were phenotyped on Nicotiana benthamiana using chlorophyll fluorescence imaging and image analysis. Wild‐type, non‐pathogenic strains induced a hypersensitive response (HR)‐like necrosis, whereas strains complemented with T3SS and T3SPs suppressed this response. Such suppression depends on a functional T3SS. Amongst the T3SPs encoded on the plasmid, Hpa2, Hpa1 and, to a lesser extent, XopF1 collectively participate in suppression. Monitoring of the population sizes in planta showed that the sole acquisition of a functional T3SS by non‐pathogenic strains impairs growth inside leaf tissues. These results provide functional evidence that the acquisition via horizontal gene transfer of a T3SS and four T3SPs by environmental non‐pathogenic strains is not sufficient to make strains pathogenic. In the absence of a canonical effector, the sole acquisition of a T3SS seems to be counter‐selective, and further acquisition of type 3 effectors is probably needed to allow the emergence of novel pathogenic strains.
Global guidelines and initiatives from the European Confederation of Medical Mycology to improve patient care and research worldwide: New leadership is about working together
Authors: Hoenigl Martin , Gangneux Jean‐Pierre , Segal Esther , Alanio Alexandre , Chakrabarti Arunaloke , Chen Sharon C.‐A. , Govender Nelesh , Hagen Ferry , Klimko Nikolaj , Meis Jacques F. , Pasqualotto Alessandro C. , Seidel Danila , Walsh Thomas J. , Lagrou Katrien , Lass‐Flörl Cornelia , Cornely Oliver A. ,   the European Confederation of Medical Mycology (ECMM)
Published: August 2018

Invasive mycoses present a global challenge with expansion into new hosts, emergence of new pathogens, and development of multidrug resistance. In parallel, new antifungal agents and advanced laboratory diagnostic systems are being developed. In response to these evolving challenges, the European Confederation of Medical Mycology (ECMM) is committed to providing international expertise, guidance, and leadership with the key objectives of improving diagnosis, treatment, outcome, and survival of persons with invasive fungal diseases. Representing 25 affiliated National Medical Mycology Societies, the ECMM has developed several major ways to achieving these critical objectives: (a) tasking specific medical mycology working groups; (b) founding the ECMM Academy and Fellow program (FECMM); (c) expanding the goals of ECMM beyond the European region; (d) implementing the ECMM Excellence Centre Initiative in Europe; and (e) the ECMM Global Guidelines and Neglected Orphan Disease Guidance Initiatives focusing on mucormycosis, rare mould diseases, rare yeast diseases, and endemic mycoses. We believe that these important initiatives and other strategies of the ECMM will advance the field of medical mycology and improve the outcome of patients with invasive mycoses worldwide.
Psychometric properties of the Chinese version of the Stress‐Related Growth Scale: Short Form in undergraduate nursing students
Authors: Li Ting , Wang Su‐Wei , Zhou Jing‐Jing , Ren Qing‐Zhuo , Gao Yu‐Lin
Published: August 2018

In this study, we examined the psychometric properties of the Chinese version of the Stress‐Related Growth Scale–Short Form (SRGS‐SF) for undergraduate nursing students. Using a cross‐sectional design, a convenience sample of 253 undergraduate nursing students was included in this study. Half of the sample (n = 126) was randomly selected to explore the factorial structure of the SRGS‐SF via exploratory factor analysis. The rest of the sample (n = 127) was selected to confirm the structure via confirmatory factor analysis. The results showed that the Chinese version of the SRGS‐SF consisted of two factors: interpersonal and intrapersonal growth. The scale also had the power to discriminate between undergraduate nursing students with high and low levels of stress‐related growth (SRG). The internal consistency and stability of the scale were also adequate. The Chinese version of the SRGS‐SF is a valid and reliable measurement for assessing SRG among undergraduate nursing students. One suitable application would be the evaluation of the process underpinning SRG and the effectiveness of interventions.
Balancing protection and efficiency in the regulation of photosynthetic electron transport across plant evolution
Authors: Alboresi Alessandro , Storti Mattia , Morosinotto Tomas
Published: August 2018

Contents

Summary
105

I.
Introduction
105

II.
Diversity of molecular mechanisms for regulation of
photosynthetic electron transport
106

III.
Role of FLVs in the regulation of photosynthesis in eukaryotes
107

IV.
Why were FLVs lost in angiosperms?
108

V.
Conclusions
108

Acknowledgements
109

References
109

Photosynthetic electron transport requires continuous modulation to maintain the balance between light availability and metabolic demands. Multiple mechanisms for the regulation of electron transport have been identified and are unevenly distributed among photosynthetic organisms. Flavodiiron proteins (FLVs) influence photosynthetic electron transport by accepting electrons downstream of photosystem I to reduce oxygen to water. FLV activity has been demonstrated in cyanobacteria, green algae and mosses to be important in avoiding photosystem I overreduction upon changes in light intensity. FLV‐encoding sequences were nevertheless lost during evolution by angiosperms, suggesting that these plants increased the efficiency of other mechanisms capable of accepting electrons from photosystem I, making the FLV activity for protection from overreduction superfluous or even detrimental for photosynthetic efficiency.
Efficacy of xenogeneic collagen matrix in the treatment of gingival recessions: A systematic review and meta‐analysis
Authors: Huang Jia‐Ping , Liu Jia‐Mei , Wu Yan‐Min , Chen Li‐Li , Ding Pei‐Hui
Published: August 2018

Objectives

This review aims to evaluate the efficacy of xenogeneic collagen matrix (XCM) for the treatment of single or multiple gingival recessions in terms of clinical parameters and patient‐related outcomes.

Materials and Methods

Various electronic databases (The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, etc.) from 1966 to April 2018 and hand literatures were searched. Quality of the included studies was assessed through the Cochrane Collaboration’s Risk of Bias tool. A meta‐analysis was performed to calculate risk ratios and mean differences.

Results

Nine randomized controlled trials were included. The results revealed a higher percentage of mean root coverage (MRC) and a greater recession reduction (RecRed) for single recessions for the combination of coronally advanced flap (CAF) with XCM compared to CAF alone (n = 3; MD = 10.00%; 95%CI [3.56%; 16.43%]; p = 0.002) (n = 3; MD = 0.35 mm; 95%CI [0.10 mm; 0.60 mm]; p = 0.005). Comparing XCM with connective tissue graft (CTG), no significant differences were detected in MRC or RecRed for single and multiple recessions.

Conclusions

The addition of XCM under CAF could improve MRC and RecRed at single tooth recessions. Initial data suggest that XCM shows promising results to improve the clinical efficacy of CAF for multiple recessions. In addition, XCM could be a valid alternative to CTG in terms of MRC and RecRed at both single and multiple recessions. Based on limited evidence, XCM may decrease postoperative morbidity and operation time compared to CTG.
Computational models evaluating the impact of sieve plates and radial water exchange on phloem pressure gradients
Authors: Stanfield Ryan C. , Schulte Paul J. , Randolph Katie E. , Hacke Uwe G.
Published: August 2018

The sugar conducting phloem in angiosperms is a high resistance pathway made up of sieve elements bounded by sieve plates. The high resistance generated by sieve plates may be a trade‐off for promoting quick sealing in the event of injury. However, previous modeling efforts have demonstrated a wide variation in the contribution of sieve plates towards total sieve tube resistance. In the current study, we generated high resolution scanning electron microscope images of sieve plates from balsam poplar and integrated them into a mathematical model using Comsol Multiphysics software. We found that sieve plates contribute upwards of 85% towards total sieve tube resistance. Utilizing the Navier–Stokes equations, we found that oblong pores may create over 50% more resistance in comparison with round pores of the same area. Although radial water flows in phloem sieve tubes have been previously considered, their impact on alleviating pressure gradients has not been fully studied. Our novel simulations find that radial water flow can reduce pressure requirements by half in comparison with modeled sieve tubes with no radial permeability. We discuss the implication that sieve tubes may alleviate pressure requirements to overcome high resistances by regulating their membrane permeability along the entire transport pathway.
Apnea in infants hospitalized with pertussis: Incidence and gestational smoking association
Authors: Ramos‐Fernández José Miguel , Sánchez‐Pérez Margarita , Sánchez‐González Jorge Miguel , Calvo‐Cillán Alicia , Moreno‐Pérez David
Published: August 2018

Background

Apnea is a life‐threatening complication of pertussis, now a re‐emerging cause of infant hospitalization worldwide. The incidence of apnea during pertussis ranges widely. The aim of this study was therefore to determine the incidence of apnea in hospitalized infants diagnosed with pertussis and to identify relevant risk factors for apnea.

Methods

This was a retrospective analytical study. We included children hospitalized with pertussis at a tertiary hospital during a 5 year period from 2010 to 2015. Nasopharyngeal aspirates (NPA) were obtained in all subjects. Real‐time polymerase chain reaction was used to test NPA samples for Bordetella pertussis. The daily charts were assessed to identify inpatients with apnea. Multivariable logistic regression was performed to identify independent risk factors for inpatient apnea.

Results

Inpatient apnea was identified in 51 of 147 infants with pertussis confirmation (34.7%: 95%CI: 27–42%). Maternal smoking during pregnancy was the only statistically significant, independent predictor of inpatient apnea (OR: 4.48; 95%CI: 1.35–14.8). No statistically significant association was found with gender, corrected age; birthweight, caregiver smoking; lactation, weight at admission <3rd percentile, or hematological parameters.

Conclusions

The incidence of pertussis apnea was nearly one in three hospitalized infants, and was fourfold more frequent in infants whose mothers smoked during pregnancy.