bluuebunny/crossref_metadata_2025 huggingface dataset:
Osteoradionecrosis of the Temporal Bone: An Evidence-Based Approach
Authors: Yuhan Brian T. , Nguyen Brandon K. , Svider Peter F. , Raza Syed N. , Hotaling Jeffrey , Chan Eleanor , Hong Robert S.
Published: August 2018

Objectives:

To perform a systematic review evaluating etiologies, associated complications, and management of osteoradionecrosis of the temporal bone (ORNTB).

Methods:

The authors searched the PubMed, Embase, and Cochrane Library databases for relevant literature. Patient demographics, etiologies, treatments, and other clinical characteristics were obtained. Treatment success was defined as resolution of symptoms at last follow-up. Results were reported using the preferred reporting systems for systematic reviews and meta-analysis (PRISMA) guidelines.

Results:

Thirty-eight studies encompassing 364 patients with ORNTB were identified. The most common etiologies necessitating radiotherapy included: nasopharyngeal carcinoma (n = 133 [36.8%]), parotid tumors (n = 73 [20.2%]), and external auditory canal pathology (n = 59 [16.3%]). The mean dose of radiation was 58.0 Gy. The mean lag time between radiotherapy and osteoradionecrosis (ORN) symptoms was 7.9 years. The most common presenting symptoms were purulent otorrhea (33.3%), hearing loss (29.1%), and otalgia (17%). ORNTB complications included tympanic membrane perforation (n = 102 [63.8%]) and chronic otitis media (n = 16 [10%]). Treatments included lateral temporal bone resection (n = 99 [28.3%]), conservative treatment (n = 92 [26.3%]), and mastoidectomy (n = 82 [23.5%]) with 90.9, 89.13, and 59.76% considered successful, respectively.

Conclusions:

ORNTB is a rare complication of radiotherapy that may present years after initial radiation exposure. Management should be aimed at relief of presenting symptoms and treatment of ORNTB associated complications. Both conservative and surgical measures may adequately control the disease process and symptomatology; however, randomized controlled studies comparing treatments would serve to further corroborate these findings.
The Performance of Patient-reported Outcome Measures as Diagnostic Tools for Eustachian Tube Dysfunction
Authors: Smith Matthew E. , Cochrane Isabelle L. , Donnelly Neil , Axon Patrick R. , Tysome James R.
Published: August 2018

Objective:

To develop and validate a novel patient-reported outcome measure (PROM) to distinguish patulous from obstructive Eustachian Tube Dysfunction (ETD). To determine accuracy of PROMs and ET function tests as diagnostic tools for ETD.

Study Design:

1) PROM development and validation. 2) Test case-control diagnostic accuracy study.

Interventions:

Cambridge ETD Assessment (CETDA) and ETDQ-7 PROMs, sonotubometry and tubomanometry ET function tests.

Setting:

Tertiary referral center.

Patients:

Cases with patulous (n = 7) or obstructive (n = 60) ETD, controls with either no ear symptoms (n = 33), or symptoms arising from hearing loss or Menière's disease (n = 24).

Main Outcome Measures:

PROMs were assessed in terms of internal consistency, ceiling and floor effects, test–retest reliability and content, structural and criterion validity. PROMs and function test sensitivity and specificity was determined as diagnostic tests for ETD.

Results:

The 10-item CETDA was developed. CETDA validity and performance were good, though five items suffered floor effects. There was no difference in scores for either PROM in the patulous ETD, obstructive ETD, and symptomatic control groups. Both PROMS had excellent diagnostic accuracy using only healthy controls as comparator for ETD, but specificity was very poor when controls with other otological disorders were included. Both objective tests had sensitivity and specificity of 63% and 79% for obstructive ETD.

Conclusions:

The CETDA and ETDQ-7 are not disease-specific and cannot distinguish obstructive from patulous ETD subtypes. A relatively weak correlation between sonotubometry and tubomanometry results, PROM scores, and the clinical diagnosis suggests that a varied core set of outcome measures is required to monitor response to treatments for ETD.
Impact of Colonoscopy Bowel Preparation Quality on Follow-up Interval Recommendations for Average-risk Patients With Normal Screening Colonoscopies
Authors: Butterly Lynn F. , Nadel Marion R. , Anderson Joseph C. , Robinson Christina M. , Weiss Julia E. , Lieberman David , Shapiro Jean A.
Published: August 2018

Background and Aims:

National guidelines for colonoscopy screening and surveillance assume adequate bowel preparation. We used New Hampshire Colonoscopy Registry (NHCR) data to investigate the influence of bowel preparation quality on endoscopist recommendations for follow-up intervals in average-risk patients following normal screening colonoscopies.

Methods:

The analysis included 9170 normal screening colonoscopies performed on average risk individuals aged 50 and above between February 2005 and September 2013. The NHCR Procedure Form instructs endoscopists to score based on the worst prepped segment after clearing all colon segments, using the following categories: excellent (essentially 100% visualization), good (very unlikely to impair visualization), fair (possibly impairing visualization), and poor (definitely impairing visualization). We categorized examinations into 3 preparation groups: optimal (excellent/good) (n=8453), fair (n=598), and poor (n=119). Recommendations other than 10 years for examinations with optimal preparation, and >1 year for examinations with poor preparation, were considered nonadherent.

Results:

Of all examinations, 6.2% overall received nonadherent recommendations, including 5% of examinations with optimal preparation and 89.9% of examinations with poor preparation. Of normal examinations with fair preparation, 20.7% of recommendations were for an interval <10 years. Among those examinations with fair preparation, shorter-interval recommendations were associated with female sex, former/nonsmokers, and endoscopists with adenoma detection rate ≥20%.

Conclusions:

In 8453 colonoscopies with optimal preparations, most recommendations (95%) were guideline-adherent. No guideline recommendation currently exists for fair preparation, but in this investigation into community practice, the majority of the fair preparation group received 10-year follow-up recommendations. A strikingly high proportion of examinations with poor preparation received a follow-up recommendation greater than the 1-year guideline recommendation. Provider education is needed to ensure that patients with poor bowel preparation are followed appropriately to reduce the risk of missing important lesions.
Early Enteral Nutrition Prevent Acute Pancreatitis From Deteriorating in Obese Patients
Authors: Jin Zhouxiang , Wang Zhaohong , Wang Jisheng
Published: August 2018

Goals:

The aim of this study was to determine a potential strategy to prevent acute pancreatitis (AP) from deteriorating in obese patients.

Background:

Nutritional support plays a critical role in the treatment of AP. Early enteral nutrition (EEN) is considered to be able to protect mucosa of AP patients and alleviate inflammatory reactions. Obesity worsen AP prognosis. However, little is known about the effects of EEN in obese patients.

Study:

Prospective randomized control trial. Subjects with moderately severe AP or severe AP were divided into the visceral fat obesity (VFO) group and the non-VFO group by obesity index VFO. The patients received “delayed” enteral nutrition (started enteral nutrition feeding after the first 48 hours after admission to the hospital: group A: patients of non-VFO, n=108; group B: VFO patients, n=88) or EEN (in the VFO subgroup, group C: n=91).Occurrence of complication, clinical outcomes, plasma levels of cytokines, and intestine gut barrier index were measured at different timepoints after admission.

Results:

VFO was a risk factor for aggravating of AP. EEN prevented the VFO patients from developing pancreatic necrotic infection, the mechanism of which might be related with inhibiting excessive inflammatory reactions, adjusting the imbalance of inflammatory response, and alleviating ischemia of intestine mucosa.

Conclusions:

The potential strategy, EEN, was able to prevent AP from deteriorating in obese patients.
Fibroscan Reliably Rules Out Advanced Liver Fibrosis and Significant Portal Hypertension in Alcoholic Patients
Authors: Salavrakos Melissa , Piessevaux Hubert , Komuta Mina , Lanthier Nicolas , Stärkel Peter
Published: August 2018

Background/Goals:

To date, there is no consensus on optimal cut-off values and timing of transient elastography (TE, Fibroscan) for fibrosis staging and prediction of portal hypertension in alcoholic liver disease. We evaluated the accuracy of Fibroscan for the diagnosis of fibrosis and clinically significant portal hypertension in alcoholic patients.

Study:

Heavy drinkers admitted to our standardized alcohol withdrawal program were evaluated by Fibroscan, by transjugular hepatic venous pressure gradient (HVPG) measurement and liver biopsy if significant fibrosis was suspected and by upper gastrointestinal endoscopy. All investigations were performed within 3 days of admission. Patients who had remained abstinent for 2 weeks underwent a second Fibroscan.

Results:

A total of 118 patients were included. Fibroscan correlated well with histology and HVPG. Negative predictive value of 92% and 93% for ruling out severe fibrosis (≥F3) and cirrhosis, and optimal cut-offs at ≥11.7, ≥15.2, and ≥21.2 kPa for F2, F3, and F4, respectively, were found. In abstinent patients, a mean decrease of 2.7 kPa improved concordance between Fibroscan and histology. A TE value of 30.6 kPa predicted a HVPG>10 mm Hg with 94% specificity and showed a good negative predictive value of 84% for ruling out the presence of varices at endoscopy. Steatosis, alcoholic hepatitis, sinusoidal fibrosis, cholestasis, and high transaminases did not influence TE values.

Conclusions:

Fibroscan is an accurate non-invasive method for the diagnosis of fibrosis in alcoholic patients. TE values below 11 and 30 kPa likely rule out significant fibrosis and varices, respectively.
Association of smoking with liver fibrosis and mortality in primary biliary cholangitis
Authors: Mantaka Aikaterini , Koulentaki Mairi , Samonakis Dimitrios , Sifaki-Pistolla Dimitra , Voumvouraki Argyro , Tzardi Maria , Kouroumalis Elias
Published: August 2018

Background

The outcome of primary biliary cholangitis (PBC) is affected by both genetic and environmental factors.

Objective

The aim of this study was to study the effect of smoking on liver histology and mortality in a genetically homogeneous population having PBC.

Patients and methods

Smoking and drinking habits at diagnosis (based on standard criteria) were recorded in 171 Cretan patients with PBC (163 women). A total of 148 patients had a liver biopsy. Odds ratios were calculated with logistic regression analysis. Kaplan–Meier curves were used for mortality estimation.

Results

Smoking was associated with alcohol consumption of more than 20 g/day [adjusted odds ratio (AOR)=2.20, 95% CI: 1.029–4.099], severe steatosis (AOR=5.31, 95% CI: 2.019–9.919), and fibrosis stage F3–F4 (AOR=1.21, 95% CI: 1.015–3.031). Heavy smoking, years of passive smoking, and serious necroinflammatiοn were independent factors associated with advanced fibrosis after adjustment for sex, age, BMI, and alcohol consumption in multivariate analysis. For every pack-year increase in smoking intensity, there was a 3.2 times higher likelihood of advanced fibrosis (95% CI: 2.018–6.294). Increased mortality was found in smokers with advanced PBC.

Conclusion

There is an association between smoking, whether active or passive, and advanced fibrosis in PBC. Mortality is increased in smokers with advanced disease at presentation.
Hemolysis During Pediatric Extracorporeal Membrane Oxygenation: Associations With Circuitry, Complications, and Mortality
Authors: Dalton Heidi J. , Cashen Katherine , Reeder Ron W. , Berg Robert A. , Shanley Thomas P. , Newth Christopher J. L. , Pollack Murray M. , Wessel David , Carcillo Joseph , Harrison Rick , Dean J. Michael , Meert Kathleen L. ,   for the Eunice Kennedy Shriver National Institute of Child Health and Human Development Collaborative Pediatric Critical Care Research Network (CPCCRN)
Published: August 2018

Objectives:

To describe factors associated with hemolysis during pediatric extracorporeal membrane oxygenation and the relationships between hemolysis, complications, and mortality.

Design:

Secondary analysis of data collected prospectively by the Collaborative Pediatric Critical Care Research Network between December 2012 and September 2014.

Setting:

Three Collaborative Pediatric Critical Care Research Network-affiliated hospitals.

Patients:

Age less than 19 years and treated with extracorporeal membrane oxygenation.

Interventions:

None.

Measurements and Main Results:

Hemolysis was defined based on peak plasma free hemoglobin levels during extracorporeal membrane oxygenation and categorized as none (< 0.001 g/L), mild (0.001 to < 0.5 g/L), moderate (0.5 to < 1.0 g/L), or severe (≥ 1.0 g/L). Of 216 patients, four (1.9%) had no hemolysis, 67 (31.0%) had mild, 51 (23.6%) had moderate, and 94 (43.5%) had severe. On multivariable analysis, variables independently associated with higher daily plasma free hemoglobin concentration included the use of in-line hemofiltration or other continuous renal replacement therapy, higher hemoglobin concentration, higher total bilirubin concentration, lower mean heparin infusion dose, lower body weight, and lower platelet count. Using multivariable Cox modeling, daily plasma free hemoglobin was independently associated with development of renal failure during extracorporeal membrane oxygenation (defined as creatinine > 2 mg/dL [> 176.8 μmol/L] or use of in-line hemofiltration or continuous renal replacement therapy) (hazard ratio, 1.04; 95% CI, 1.02–1.06;p< 0.001), but not mortality (hazard ratio, 1.01; 95% CI, 0.99–1.04;p= 0.389).

Conclusions:

Hemolysis is common during pediatric extracorporeal membrane oxygenation. Hemolysis may contribute to the development of renal failure, and therapies used to manage renal failure such as in-line hemofiltration and other forms of continuous renal replacement therapy may contribute to hemolysis. Hemolysis was not associated with mortality after controlling for other factors. Monitoring for hemolysis should be a routine part of extracorporeal membrane oxygenation practice, and efforts to reduce hemolysis may improve patient care.
Recent developments in the epidemiology, diagnosis, and treatment of Fasciola infection
Authors: Webb Camille M. , Cabada Miguel M.
Published: August 2018

Purpose of review

This review aims at describing the latest research in Fasciola epidemiology, diagnosis, treatment, and control in endemic countries.

Recent findings

The geographic distribution and range of reservoirs for Fasciola hepatica continues to expand. The impact of fascioliasis goes beyond human disease to affect food security and income in developed and developing countries. Promising serologic and molecular methods to diagnose fascioliasis have been described, but are not widely available. Triclabendazole remains the only highly active medication to treat human and livestock infected with juvenile and adult forms of Fasciola spp. Efforts to control fascioliasis may be hindered by the emergence of resistance to triclabendazole among livestock and subsequently in humans.

Increased awareness and surveillance are likely to uncover the real distribution and burden of fascioliasis in human. Research into new drugs or adjuvants to tackle the emerging resistance to triclabendazole is imperative to treat and control Fasciola infection.
Imported onchocerciasis in migrants and travelers
Authors: Showler Adrienne J. , Nutman Thomas B.
Published: August 2018

Purpose of review

With increasing international travel and mass global population migration, clinicians in nonendemic countries must be familiar with imported neglected tropical diseases including onchocerciasis, which is commonly known as ‘river blindness’.

Recent findings

Imported onchocerciasis manifests differently in travelers compared with migrants from endemic areas and is likely underdiagnosed in both groups. Recent clinical studies confirm that eosinophilia is not a sensitive marker for Onchocerca volvulus, with one-third of patients having a normal eosinophil count. Novel diagnostics measuring antibodies to multiple recombinant O. volvulus antigens maintain a high sensitivity while improving specificity compared with conventional pan-filarial serologic testing. A 6-week course of doxycycline has macrofilaricidal activity through Wolbachia depletion and may be useful in nonendemic areas in addition to standard serial ivermectin.

Recent studies characterizing distinct clinical presentations in travelers and migrants may enable clinicians to better recognize imported onchocerciasis. Although novel diagnostics have improved specificity, most remain restricted to tropical disease reference laboratories and to date there is no marker of cure. Prolonged doxycycline treatment may reduce the need for serial ivermectin, though more potent short-course macrofilaricidal drugs are being developed.
Cyclin B3 promotes APC/C activation and anaphase I onset in oocyte meiosis
Authors: Karasu Mehmet E. , Bouftas Nora , Keeney Scott , Wassmann Katja
Published: August 2018

As obligate kinase partners, cyclins control the switch-like cell cycle transitions that orchestrate orderly duplication and segregation of genomes. Meiosis, the cell division that generates gametes for sexual reproduction, poses unique challenges because two rounds of chromosome segregation must be executed without intervening DNA replication. Mammalian cells express numerous, temporally regulated cyclins, but how these proteins collaborate to control meiosis remains poorly understood. Here, we delineate an essential function for mouse cyclin B3 in the first meiotic division of oocytes. Females genetically ablated for cyclin B3 are viable, indicating the protein is dispensable for mitotic divisions, but are sterile. Mutant oocytes appear normal until metaphase I but then display a highly penetrant failure to transition to anaphase I. They arrest with hallmarks of defective APC/C activation, including no separase activity and high MPF, cyclin B1, and securin levels. Partial APC/C activation occurs, however, as exogenously expressed APC/C substrates can be degraded and arrest can be suppressed by inhibiting MPF kinase. Cyclin B3 is itself targeted for degradation by the APC/C. Cyclin B3 forms active kinase complexes with CDK1, and meiotic progression requires cyclin B3-associated kinase activity. Collectively, our findings indicate that cyclin B3 is essential for oocyte meiosis because it fine-tunes APC/C activity as a kinase-activating CDK partner. Cyclin B3 homologs from frog, zebrafish, and fruitfly rescue meiotic progression in cyclin B3-deficient mouse oocytes, indicating conservation of the biochemical properties and possibly cellular functions of this germline-critical cyclin.
Refinement of anesthetic choice in procedures preceding psychopharmacological studies
Authors: Herbst LS , Gaigher T , Siqueira AA , Joca SRL , Sampaio KN , Beijamini V
Published: August 2018

Rationale

Previous studies indicated that some general anesthetics induce long-term antidepressant and/or anxiolytic-like effects. This raises the concern about the use of anesthesia in surgeries that precede psycopharmacological tests, since it may be a potential bias on results depending on the experimental design used.

Objectives

To evaluate whether commonly used general anesthetics in surgeries preceding psychopharmacological tests would affect rat behavior in tests predictive of antidepressant or anxiolytic-like effects. We also evaluated whether prior anesthesia would interfere in the detection of the antidepressant-like effect of imipramine or the anxiolytic-like effect of diazepam.

Methods

We tested if a single exposure to subanesthetic or anesthetic doses of 2,2,2-tribromoethanol, chloral hydrate, thiopental or isoflurane would change rat’s behavior in the forced swimming test (FST) or in the elevated plus-maze (EPM) test, at 2 hours or 7 days after administration.

Results

Previous anesthesia with the aforementioned anesthetics did not change rat behavior in FST per se nor it changed the antidepressant-like effect induced by imipramine treatment. Rats previously anesthetized with tribromoethanol or chloral hydrate exhibited, respectively, anxiogenic-like or anxiolytic-like behavior in the EPM. Prior anesthesia with thiopental or isoflurane did not produce anyper seeffect in rat behavior in the EPM nor disturbed the anxiolytic-like effect of diazepam.

Conclusion

Our results suggest that, in our experimental conditions, tribromoethanol and chloral hydrate are improper anesthetics for surgeries that precede behavioral tests related to anxiety. Isoflurane or thiopental may be suitable for anesthesia before evaluation in animal models predictive of antidepressant or anxiolytic-like effect.
Boundaries in Spatial Cognition: Looking like a Boundary is More Important than Being a Boundary
Authors: Negen James , Sandri Angela , Lee Sang Ah , Nardini Marko
Published: August 2018

Large walls and other typical boundaries strongly influence neural activity related to navigation and the representations of spatial layouts. They are also major aids to reliable navigation behavior in young children and non-human animals. Is this because they are physical boundaries (barriers to movement), or because they present certain visual features, such as visually extended 3D surfaces? Here, these two factors were dissociated by using immersive virtual reality and real boundaries. Eighty adults recalled target locations in one of four environments: plywood, where a virtual wall coincided with a large piece of real plywood; pass through, where the virtual wall coincided with empty space and participants could pass through it; pass over, where the virtual wall was projected downward to be visible underneath a transparent floor; and cones, where the walls were replaced with traffic cones. One condition had features that were boundaries and looked like boundaries (plywood); two had features that were not boundaries but looked like boundaries (pass over/through); and one had features that were not boundaries and did not look like boundaries (cones). The precision and bias of responses changed only as a function of looking like a boundary. This suggests that variations in spatial coding are more closely linked to the visual properties of environmental layouts than to whether they contain physical boundaries (barriers to movement).
Deforming the metric of cognitive maps distorts memory
Authors: Bellmund Jacob L. S. , de Cothi William , Ruiter Tom A. , Nau Matthias , Barry Caswell , Doeller Christian F.
Published: August 2018

Environmental boundaries anchor cognitive maps that support memory. However, trapezoidal boundary geometry distorts the regular firing patterns of entorhinal grid cells proposedly providing a metric for cognitive maps. Here, we test the impact of trapezoidal boundary geometry on human spatial memory using immersive virtual reality. Consistent with reduced regularity of grid patterns in rodents and a grid-cell model based on the eigenvectors of the successor representation, human positional memory was degraded in a trapezoid compared to a square environment; an effect particularly pronounced in the trapezoid’s narrow part. Congruent with spatial frequency changes of eigenvector grid patterns, distance estimates between remembered positions were persistently biased; revealing distorted memory maps that explained behavior better than the objective maps. Our findings demonstrate that environmental geometry affects human spatial memory similarly to rodent grid cell activity — thus strengthening the putative link between grid cells and behavior along with their cognitive functions beyond navigation.
Development of a multi-locus CRISPR gene drive system in budding yeast
Authors: Yan Yao , Finnigan Gregory C.
Published: August 2018

The discovery of CRISPR/Cas gene editing has allowed for major advances in many biomedical disciplines and basic research. One arrangement of this biotechnology, a nuclease-based gene drive, can rapidly deliver a genetic element through a given population and studies in fungi and metazoans have demonstrated the success of such a system. This methodology has the potential to control biological populations and contribute to eradication of insect-borne diseases, agricultural pests, and invasive species. However, there remain challenges in the design, optimization, and implementation of gene drives including concerns regarding biosafety, containment, and control/inhibition. Given the numerous gene drive arrangements possible, there is a growing need for more advanced designs. In this study, we use budding yeast to develop an artificial multi-locus gene drive system. Our minimal setup requires only a single copy ofS. pyogenesCas9 and three guide RNAs to propagate three separate gene drives. We demonstrate how this system could be used for targeted allele replacement of native genes and to suppress NHEJ repair systems by modifying DNA Ligase IV. A multi-locus gene drive configuration provides an expanded suite of options for complex attributes including pathway redundancy, combatting evolved resistance, and safeguards for control, inhibition, or reversal of drive action.
Hydrogenotrophic methanogenesis in archaeal phylum Verstraetearchaeota reveals the shared ancestry of all methanogens
Authors: Berghuis Bojk A. , Yu Feiqiao Brian , Schulz Frederik , Blainey Paul C. , Woyke Tanja , Quake Stephen R.
Published: August 2018

Methanogenic archaea are major contributors to the global carbon cycle and were long thought to belong exclusively to the euryarchaeotal phylum. Discovery of the methanogenesis gene cluster methyl-coenzyme M reductase (Mcr) in the Bathyarchaeota and thereafter the Verstraetearchaeota led to a paradigm shift, pushing back the evolutionary origin of methanogenesis to pre-date that of the Euryarchaeota. The methylotrophic methanogenesis found in the non-Euryarchaota distinguished itself from the predominantly hydrogenotrophic methanogens found in euryarchaeal orders as the former do not couple methanogenesis to carbon fixation through the reductive acetyl-coenzyme A (Wood-Ljungdahl) pathway, which was interpreted as evidence for independent evolution of the two methanogenesis pathways. Here, we report the discovery of a complete and divergent hydrogenotrophic methanogenesis pathway in a novel, thermophilic order of the Verstraetearchaeota which we have named Candidatus Methanohydrogenales, as well as the presence of the Wood-Ljungdahl pathway in the crenarchaeal order Desulfurococcales. Our findings support the ancient origin of hydrogenotrophic methanogenesis, suggest that methylotrophic methanogenesis might be a later adaptation of specific orders, and provide insight into how transition from hydrogenotrophic to methylotrophic methanogenesis might occur.
A widespread coral-infecting apicomplexan contains a plastid encoding chlorophyll biosynthesis
Authors: Kwong Waldan K. , Campo Javier del , Mathur Varsha , Vermeij Mark J. A. , Keeling Patrick J.
Published: August 2018

The Apicomplexa are an important group of obligate intracellular parasites that include the causative agents of human diseases like malaria and toxoplasmosis. They evolved from free-living, phototrophic ancestors, and how this transition to parasitism occurred remains an outstanding question. One potential clue lies in coral reefs, where environmental DNA surveys have uncovered several lineages of uncharacterized, basally-branching apicomplexans. Reef-building corals form a well-studied symbiotic relationship with the photosynthetic dinoflagellateSymbiodinium, but identification of other key microbial symbionts of corals has proven elusive. Here, we used community surveys, genomics, and microscopy to identify an apicomplexan lineage, which we name ‘corallicola’, that was found in high prevalence (>80%) across all major groups of corals. In-situ fluorescence and electron microscopy confirmed that corallicola lives intracellularly within the tissues of the coral gastric cavity, and possesses clear apicomplexan ultrastructural features. We sequenced the plastid genome, which lacked all genes for photosystem proteins, indicating that corallicola harbours a non-photosynthetic plastid (an apicoplast). However, the corallicola plastid differed from all other known apicoplasts because it retains all four genes involved in chlorophyll biosynthesis. Hence, corallicola shares characteristics with both its parasitic and free-living relatives, implicating it as an evolutionary intermediate, and suggesting that a unique ancestral biochemistry likely operated during the transition from phototrophy to parasitism.
Genomic from Plasmodium falciparum field isolates from Benin allows the identification of PfEMP1 variants by LC-MS/MS at the patient’s level
Authors: Kamaliddin Claire , Rombaut David , Guillochon Emilie , Royo Jade , Ezinmegnon Sem , Huguet Stéphanie , Guemouri Sayeh , Peirera Céline , Broussard Cédric , Alao Jules M , Aubouy Agnès , Guillonneau François , Deloron Philippe , Bertin Gwladys
Published: August 2018

PfEMP1 are the major protein family from parasitic origin involves in the pathophysiology of severe malaria, and PfEMP1 domain subtypes are associated with the infection outcome. In addition, PfEMP1 variability in endless and current protein repository do not reflect the immense diversity of the sequences of PfEMP1 proteins. The aim of our study was to identify the different PfEMP1 variants expressed within a patient sample by mass spectrometry. We performed a proteogenomic approach to decipher at the patient’s level PfEMP1 expression in different clinical settings: cerebral malaria, severe anemia and uncomplicated malaria. The combination of whole genome sequencing approach, RNAsequencing, and mass spectrometry proteomic analysis allowed to attribute PfEMP1 sequences to each sample and classify the relative expression level of PfEMP1 proteins within each sample. We predicted PfEMP1 structures using the newly identified protein sequences. We confirmed the involvement of DBLβ in malaria pathogenesis and observed that CIDRα domains linked to ICAM-1 binding DBLβ domains displayed EPCR binding structure.
Quantitative modelling predicts the impact of DNA methylation on RNA polymerase II traffic
Authors: Cholewa-Waclaw Justyna , Shah Ruth , Webb Shaun , Chhatbar Kashyap , Ramsahoye Bernard , Pusch Oliver , Yu Miao , Greulich Philip , Waclaw Bartlomiej , Bird Adrian
Published: August 2018

Patterns of gene expression are primarily determined by proteins that locally enhance or repress transcription. While many transcription factors target a restricted number of genes, others appear to modulate transcription levels globally. An example is MeCP2, an abundant methylated-DNA binding protein that is mutated in the neurological disorder Rett Syndrome. Despite much research, the molecular mechanism by which MeCP2 regulates gene expression is not fully resolved. Here we integrate quantitative, multi-dimensional experimental analysis and mathematical modelling to show that MeCP2 is a novel type of global transcriptional regulator whose binding to DNA creates "slow sites" in gene bodies. Waves of slowed-down RNA polymerase II formed behind these sites travel backward and indirectly affect initiation, reminiscent of defect-induced shock waves in non-equilibrium physics transport models. This mechanism differs from conventional gene regulation mechanisms, which often involve direct modulation of transcription initiation. Our findings uncover a genome-wide function of DNA methylation that may account for the reversibility of Rett syndrome in mice. Moreover, our combined theoretical and experimental approach provides a general method for understanding how global gene expression patterns are choreographed.
Structural basis for ligand modulation of the CCR2 conformational landscape
Authors: Taylor Bryn C. , Lee Christopher T. , Amaro Rommie E.
Published: August 2018

CC Chemokine Receptor 2 (CCR2) is a part of the chemokine receptor family, an important class of therapeutic targets. These class A G-protein coupled receptors (GPCRs) are involved in mammalian signaling pathways and control cell migration toward endogenous CC chemokine ligands. Chemokine receptors and their associated ligands are involved in a wide range of diseases and thus have become important drug targets. Of particular interest is CCR2, which has been implicated in cancer, autoimmunity driven type-1 diabetes, diabetic nephropathy, multiple sclerosis, asthma, atherosclerosis, neuropathic pain, and rheumatoid arthritis. Although promising, CCR2 antagonists have been largely unsuccessful to date. Here, we investigate the effect of an orthosteric and an allosteric antagonist on CCR2 dynamics by coupling long timescale molecular dynamics simulations with Markov-state model theory. We find that the antagonists shift CCR2 into several stable inactive conformations that are distinct from the crystal structure conformation, and that they disrupt a continuous internal water and sodium ion pathway preventing transitions to an active-like state. Several of these stable conformations contain a putative drug binding pocket that may be amenable to targeting with another small molecule antagonist. In the absence of antagonists, the apo dynamics reveal intermediate conformations along the activation pathway that provide insight into the basal dynamics of CCR2, and may also be useful for future drug design.
Two new Rb–Ga arsenates: RbGa(HAsO4)2 and RbGa2As(HAsO4)6
Authors: Schwendtner Karolina , Kolitsch Uwe
Published: August 2018

The crystal structures of hydrothermally synthesized (T = 493 K, 7–9 d) rubidium gallium bis[hydrogenarsenate(V)], RbGa(HAsO4)2, and rubidium digallium arsenic(V) hexa[hydrogenarsenate(V)], RbGa2As(HAsO4)6, were solved by single-crystal X-ray diffraction. Both compounds have tetrahedral–octahedral framework topologies. The M
+ cations are located in channels of the respective framework. RbGa(HAsO4)2 crystallizes in the RbFe(HPO4)2 structure type (R\overline{3}c), while RbGa2As(HAsO4)6 adopts the structure type of RbAl2As(HAsO4)6 (R\overline{3}c), which represents a modification of the RbFe(HPO4)2 structure type. In this modification, one third of the M
3+O6 octahedra are replaced by AsO6 octahedra, and two thirds of the voids in the structure, which are usually filled by M
+ cations, remain empty to achieve charge balance.
Visual servoing of dynamic wheeled mobile robots with anti-interference finite-time controllers
Authors: Chen Hua , Chen Lei , Zhang Qian , Tong Fei
Published: August 2018

Purpose

The finite-time visual servoing control problem is considered for dynamic wheeled mobile robots (WMRs) with unknown control direction and external disturbance.

Design/methodology/approach

By using finite-time control method and switching design technique.

Findings

First, the visual servoing kinematic WMR model is developed, which can be converted to the dynamic chained-form systems by using a state and input feedback transformation. Then, for two decoupled subsystems of the chained-form systems, according to the finite-time stability control theory, a discontinuous three-step switching control strategy is proposed in the presence of uncertain control coefficients and external disturbance.

Originality/value

A class of discontinuous anti-interference control method has been presented for the dynamic nonholonomic systems.
The impact of foreign capital inflows on economic growth on selected African countries
Authors: Mowlaei Mohammad
Published: August 2018

Purpose

Nowadays, foreign capital inflow (FCI) is considered as a catalyst for economic development and an important source of transferring technology and foreign exchange earnings from developed to developing countries. The purpose of this paper is to study, first, the impact of different forms of FCIs, namely, foreign direct investment (FDI), personal remittances (PR) and official development assistant (ODA) on economic growth on 26 top African countries; and, second, which of them is more effective on economic growth of the studied countries. The results of this paper are very important for host governments’ policy and help them to design their economic plans to absorb the suitable foreign inflow.

Design/methodology/approach

The paper uses Pooled Mean Group (PMG) econometric technique to estimate the heterogeneous panels over the period 1992–2016.

Findings

The results of the study show that all three forms of FCIs have positive and significant effects on economic growth in the long and short run. However, the PR had the most effect on economic growth in the long and short run. The study suggests that the governments should design and implement appropriate fiscal, monetary and trade policies in order to create and improve an enabling environment to attract FCIs as a supplementary source of domestic investment.

Research limitations/implications

The research limitations of this paper are as follows: data sets of FDI, PR and ODA were available not for all African countries; and, data sets that were available were of before the year 1992. Thus, the research is done for the African countries which had the data sets after the year 1992.

Practical implications

The result of this paper indicates the impact of each FDI, PR and ODA in economic growth. So, countries can take more attentions to each of them on economic planning.

Social implications

FCIs are one of the important external source of exchange for each country. So, the study of importance of each of them is necessary for economic planning.

Originality/value

Most of the previous studies have examined the impact of three different forms of FCIs on economic growth separately, on different countries and regions and using various models and econometric techniques. One of the contributions of this paper is focused on the impacts of FDI, PR and ODA on economic growth separately and simultaneously in 26 top recipient African countries and using the PMG technique which is an advanced econometrical estimation and studied less about it. The other contribution of this research is the comparison of the impact of different FCIs on economic growth, and it is very important for governments’ economic policy.
Can internal strategic alignment influence performance? An empirical research applying structural equation modelling
Authors: Prieto Vanderli Correia , de Carvalho Marly M.
Published: August 2018

Purpose

The purpose of this paper is to investigate the impact of internal strategic alignment (ISA) on business performance. A model is developed in which internal alignment is explained by the covariance between vertical and horizontal alignment. The perspective of business strategy implementation is adopted in order to support the theoretical relationship between the variables.

Design/methodology/approach

The partial least squares method, a structural equation modeling technique, is applied to estimate the model.

Findings

The results provide empirical validation for the model and confirm the positive relationship between internal alignment and business performance.

Practical implications

The ISA model is an essential aid for executives when implementing strategies and the validated research instrument can be applied for firms as a diagnosis of internal alignment in the organization.

Originality/value

The research contributed to meet the need for studies involving strategy implementation, as its formulation has already been emphasized, as well as to the need for models of strategic internal alignment that include activities relevant to the successful execution of the strategy, and to the need for alignment studies based on a holistic perspective.
Corruption and supply chain management toward the sustainable development goals era
Authors: Monteiro Marcelo de Sousa , Viana Fernando Luiz E. , Sousa-Filho José Milton de
Published: August 2018

Purpose

This paper aims to identify academic literature studies on corruption in the supply chain management (SCM) from 2005 to 2016 to propose a research agenda. The review links this possible new course of research within the sustainable development goals (SDGs) framework, proposed by the United Nations from 2015 to 2030.

Design/methodology/approach

A literature review method was used in the academic research to identify which approaches are used for corruption in SCM. The analysis of the context of SDGs required an integrated approach once the goals are interconnected.

Findings

Despite the increase in research studies in 2015, there is still little research focusing specifically on corruption in SCM. There is a broad opportunity to connect the research on corruption in SCM with the context of the practice to achieve the SDGs.

Originality/value

Considering the economic, social and environmental risks of corruption practices in SCM and the scarce academic literature on these themes together, a research agenda with interdisciplinary groups is suggested to deepen the subjects. There are some questions related to corruption in SCM and its connections with practice to achieve the SDGs.
Axe of kindness: introducing appreciative exnovation
Authors: November Eben David
Published: August 2018

Purpose

The purpose of this paper is to present a model of exnovation that integrates the spirit of appreciative inquiry (AI) yet addresses some of AI’s assumptions.

Design/methodology/approach

Draws on the ample AI literature, sparse exnovation literature, and uses conceptual reasoning to develop a new process called appreciative exnovation.

Findings

This paper proposes a 4-phase model of appreciative exnovation. Specifically, this paper suggests that appreciative exnovation can produce valuable future knowledge while accomplishing the necessary task of removal of innovations incongruent with current organizational needs.

Originality/value

This paper is the first to link AI and exnovation concepts. It has also critically questioned key assumptions of AI. It is also the first to suggest that exnovation may be initiated on a bottom-up basis.
Towards semantically-aided domain specific business process modeling
Authors: Lagos Nikolaos , Mos Adrian , Cortes-cornax Mario
Published: August 2018

Purpose

Domain-specific process modeling has been proposed in the literature as a solution to several problems in business process management. The problems arise when using only the generic Business Process Model and Notation (BPMN) standard for modeling. This language includes domain ambiguity and difficult long-term model evolution. Domain-specific modeling involves developing concept definitions, domain-specific processes and eventually industry-standard BPMN models. This entails a multi-layered modeling approach, where any of these artifacts can be modified by various stakeholders and changes done by one person may influence models used by others. There is therefore a need for tool support to keep track of changes done and their potential impacts. The paper aims to discuss these issues.

Design/methodology/approach

The authors use a multi-context systems-based approach to infer the impacts that changes may cause in the models; and alsothe authors incrementally map components of business process models to ontologies.

Findings

Advantages of the framework include: identifying conflicts/inconsistencies across different business modeling layers; expressing rich information on the relations between two layers; calculating the impact of changes taking place in one layer to the rest of the layers; and selecting incrementally the most appropriate semantic models on which the transformations can be based.

Research limitations/implications

The authors consider this work as one of the foundational bricks that will enable further advances toward the governance of multi-layer business process modeling systems. Extensive usability tests would enable to further confirm the findings of the paper.

Practical implications

The approach described here should improve the maintainability, reuse and clarity of business process models and in extension improve data governance in large organizations. The approaches described here should improve the maintainability, reuse and clarity of business process models. This can improve data governance in large organizations and for large collections of processes by aiding various stakeholders to understand problems with process evolutions, changes and inconsistencies with business goals.

Originality/value

This paper fulfills an identified gap to enabling semantically aided domain–specific process modeling.
Impact of cleanliness on the productivity of employees
Authors: Horrevorts Mirte , Van Ophem Johan , Terpstra Paul
Published: August 2018

Purpose

The purpose of this paper is to investigate whether the cleanliness of a work environment has influence on the productivity of employees working in office environments of non-profit organizations in The Netherlands.

Design/methodology/approach

In the study, an online survey (including questions about the perceived cleanliness) and two objective cleanliness assessment methods (particle counts and surface cleanliness) are used. The data are collected using an online questionnaire to determine the workers’ perception (of productivity and cleanliness) and to measure the cleanliness (visual assessment of the surface cleanliness and measured [dust] particle counts in the ambient air) at five different non-profit organizations in The Netherlands.

Findings

It is found that a higher objective cleanliness correlates significantly with a higher perceived productivity of employees working in office environments of non-profit organizations in The Netherlands. A higher measured cleanliness also correlates significantly with a higher work satisfaction level of employees working in office environments. Finally, a significant correlation is found between the satisfaction of employees with their work as a whole and the perceived productivity of the employees; a higher satisfaction leads to a higher perceived productivity.

Research limitations/implications

The cleanliness is measured in five non-profit organizations, so it is not possible to draw any strong generalization. Future studies are needed to confirm or contradict the findings in this research.

Practical implications

The results highlight the aspects of the cleanliness in the office environment that influence the perceived productivity. This concerns the measured cleanliness. Employees evaluate their own productivity lower at a higher level of particle counts in the ambient air in the office environment and when more dirt and stain are found on the surface (lower surface cleanliness). In response to these findings, it is recommended to carry out regular cleaning activities in the office environment where the employees perform their work. Overall, to maintain or achieve maximum personal productivity, a clean office environment is important.

Originality/value

This research is the first to identify the relationship between perceived productivity and measured cleanliness of the office environment.