bluuebunny/crossref_metadata_2025 huggingface dataset:
An insight into real and average structure from diffuse X-ray scattering – a case study
Authors: Chodkiewicz Michał Leszek , Makal Anna , Gajda Roman , Vidovic Dragoslav , Woźniak Krzysztof
Published: July 2016

Two-dimensional diffuse X-ray scattering from an organic salt [N-(3-(2,6-dimethylanilino)-1-methylbut-2-enylidene)-2,6-dimethylanilinium chloride, C21H27N2+Cl−] was interpreted with the help of an analytical model of diffuse scattering. An analysis of the relationship between symmetry and diffuse scattering for the studied system has been undertaken. The symmetry of the system explains the extinction pattern, taking the form of curves, on the diffuse scattering planes. We have also tested the relationship between the average structure model and scattering intensities. Two models, differing in their representation of overlapping atoms, were used. In the case of diffuse scattering the difference between resulting intensities is immense, while for the Bragg intensities it is much smaller. This sensitivity of diffuse scattering could potentially be used to improve the description of the average structure.
Generation of crystal structures using known crystal structures as analogues
Authors: Cole Jason C. , Groom Colin R. , Read Murray G. , Giangreco Ilenia , McCabe Patrick , Reilly Anthony M. , Shields Gregory P.
Published: July 2016

This analysis attempts to answer the question of whether similar molecules crystallize in a similar manner. An analysis of structures in the Cambridge Structural Database shows that the answer is yes – sometimes they do, particularly for single-component structures. However, one does need to define what we mean bysimilarin both cases. Building on this observation we then demonstrate how this correlation between shape similarity and packing similarity can be used to generate potential lattices for molecules with no known crystal structure. Simple intermolecular interaction potentials can be used to minimize these potential lattices. Finally we discuss the many limitations of this approach.
An optimized intermolecular force field for hydrogen-bonded organic molecular crystals using atomic multipole electrostatics
Authors: Pyzer-Knapp Edward O. , Thompson Hugh P. G. , Day Graeme M.
Published: July 2016

We present a re-parameterization of a popular intermolecular force field for describing intermolecular interactions in the organic solid state. Specifically we optimize the performance of the exp-6 force field when used in conjunction with atomic multipole electrostatics. We also parameterize force fields that are optimized for use with multipoles derived from polarized molecular electron densities, to account for induction effects in molecular crystals. Parameterization is performed against a set of 186 experimentally determined, low-temperature crystal structures and 53 measured sublimation enthalpies of hydrogen-bonding organic molecules. The resulting force fields are tested on a validation set of 129 crystal structures and show improved reproduction of the structures and lattice energies of a range of organic molecular crystals compared with the original force field with atomic partial charge electrostatics. Unit-cell dimensions of the validation set are typically reproduced to within 3% with the re-parameterized force fields. Lattice energies, which were all included during parameterization, are systematically underestimated when compared with measured sublimation enthalpies, with mean absolute errors of between 7.4 and 9.0%.
YsbA and LytST are essential for pyruvate utilization in Bacillus subtilis
Authors: van den Esker Marielle H. , Kovács Ákos T. , Kuipers Oscar P.
Published: July 2016

The genome of Bacillus subtilis encodes homologues of the Cid/Lrg network. In other bacterial species, this network consists of holin‐ and antiholin‐like proteins that regulate cell death by controlling murein hydrolase activity. The YsbA protein of B. subtilis is currently annotated as a putative antiholin‐like protein that possibly impedes cell death, whereas YwbH is thought to act as holin‐like protein. However, the actual functions of YsbA and YwbH in B. subtilis have never been characterized. Therefore, we examined the impact of these proteins on growth and cell death in B. subtilis. We did not find a connection to the regulation of programmed cell death, but instead, our experiments reveal that YsbA and its two‐component regulator LytST are essential for growth on pyruvate. Moreover, deletion of ysbA and lytS significantly reduces pyruvate consumption. Our findings suggest that LytST induces ysbA transcription in the presence of pyruvate, and that YsbA is involved in pyruvate utilization presumably by functioning as pyruvate uptake system. We show that B. subtilis excretes pyruvate as overflow metabolite in rich medium, indicating that pyruvate could be a common nutrient in the environment. Hence, YsbA and LytST might play a major role in environmental growth of B. subtilis.
Nomadic lifestyle of Lactobacillus plantarum revealed by comparative genomics of 54 strains isolated from different habitats
Authors: Martino Maria Elena , Bayjanov Jumamurat R. , Caffrey Brian E. , Wels Michiel , Joncour Pauline , Hughes Sandrine , Gillet Benjamin , Kleerebezem Michiel , van Hijum Sacha A.F.T. , Leulier François
Published: July 2016

The ability of bacteria to adapt to diverse environmental conditions is well‐known. The process of bacterial adaptation to a niche has been linked to large changes in the genome content, showing that many bacterial genomes reflect the constraints imposed by their habitat. However, some highly versatile bacteria are found in diverse habitats that almost share nothing in common. Lactobacillus plantarum is a lactic acid bacterium that is found in a large variety of habitat. With the aim of unravelling the link between evolution and ecological versatility of L. plantarum, we analysed the genomes of 54 L. plantarum strains isolated from different environments. Comparative genome analysis identified a high level of genomic diversity and plasticity among the strains analysed. Phylogenomic and functional divergence studies coupled with gene–trait matching analyses revealed a mixed distribution of the strains, which was uncoupled from their environmental origin. Our findings revealed the absence of specific genomic signatures marking adaptations of L. plantarum towards the diverse habitats it is associated with. This suggests fundamentally similar trends of genome evolution in L. plantarum, which occur in a manner that is apparently uncoupled from ecological constraint and reflects the nomadic lifestyle of this species.
Oxidation of urea‐derived nitrogen by thaumarchaeota‐dominated marine nitrifying communities
Authors: Tolar Bradley B. , Wallsgrove Natalie J. , Popp Brian N. , Hollibaugh James T.
Published: July 2016

Urea nitrogen has been proposed to contribute significantly to nitrification by marine thaumarchaeotes. These inferences are based on distributions of thaumarchaeote urease genes rather than activity measurements. We found that ammonia oxidation rates were always higher than oxidation rates of urea‐derived N in samples from coastal Georgia, USA (means ± SEM: 382 ± 35 versus 73 ± 24 nmol L−1 d−1, Mann‐Whitney U‐test p < 0.0001), and the South Atlantic Bight (20 ± 8.8 versus 2.2 ± 1.7 nmol L−1 d−1, p = 0.026) but not the Gulf of Alaska (8.8 ± 4.0 versus 1.5 ± 0.6, p > 0.05). Urea‐derived N was relatively more important in samples from Antarctic continental shelf waters, though the difference was not statistically significant (19.4 ± 4.8 versus 12.0 ± 2.7 nmol L−1 d−1, p > 0.05). We found only weak correlations between oxidation rates of urea‐derived N and the abundance or transcription of putative Thaumarchaeota ureC genes. Dependence on urea‐derived N does not appear to be directly related to pH or ammonium concentrations. Competition experiments and release of 15NH3 suggest that urea is hydrolyzed to ammonia intracellularly, then a portion is lost to the dissolved pool. The contribution of urea‐derived N to nitrification appears to be minor in temperate coastal waters, but may represent a significant portion of the nitrification flux in Antarctic coastal waters.
Effects of working memory capacity in processing wh‐extractions: eye‐movement evidence from Chinese–English bilinguals
Authors: Zhou Huixia , Rossi Sonja , Li Juan , Liu Huanhuan , Chen Ran , Chen Baoguo
Published: July 2016

By using the eye‐tracking method, the present study explores whether working memory capacity assessed via the second language (L2) reading span (L2WMC) as well as the operational span task (OSPAN) affects the processing of subject‐extraction and object‐extraction in Chinese–English bilinguals. Results showed that L2WMC has no effects on the grammatical judgement accuracies, the first fixation duration, gaze duration, go‐past times and total fixation duration of the critical regions in wh‐extractions. In contrast, OSPAN influences the first fixation duration and go‐past times of the critical regions in wh‐extractions. Specifically, in region 1, (e.g., Who do you think loved the comedian [region 1] with [region 2] all his heart [subject‐extraction]? versus Who do you think the comedian loved [region 1] with [region 2] all his heart? [object‐extraction]), participants with high OSPAN were much slower than those with low OSPAN in their first fixation duration in reading subject‐extractions, whereas there were no differences between participants with different OSPANs in reading object‐extractions. In region 2, participants with high OSPAN were much faster than those with low OSPAN in their go‐past times of object‐extractions. These results indicated that individual differences in OSPAN rather than in L2WMC more strongly affect processing of wh‐extractions. Thus, OSPAN results to be more suitable to explore the influences of working memory while processing L2 sentences with complex syntax, at least for intermediate proficient bilinguals. Results of the study also provide further support for the Capacity Theory of Comprehension.
Candidate gene analysis of osteochondrosis inSpanishPurebred horses
Authors: Sevane N. , Dunner S. , Boado A. , Cañon J.
Published: July 2016

Equine osteochondrosis (OC) is a frequent developmental orthopaedic disease with high economic impact on the equine industry and may lead to premature retirement of the animal as a result of chronic pain and lameness. The genetic background ofOCincludes different genes affecting several locations; however, these genetic associations have been tested in only one or few populations, lacking the validation in others. The aim of this study was to identify the genetic determinants ofOCin theSpanishPurebred horse breed. For that purpose, we used a candidate gene approach to study the association between loci previously implicated in the onset and development ofOCin other breeds and differentOClocations using radiographic data from 144 individuals belonging to the Spanish Purebred horse breed. Of the 48 polymorphisms analysed, three single nucleotide polymorphisms (SNPs) located in theFAF1,FCN3andCOL1A2genes were found to be associated with different locations ofOClesions. These data contribute insights into the complex gene networks underlying the multifactorial diseaseOC, and the associatedSNPs could be used in a marker‐assisted selection strategy to improve horse health, welfare and competitive lifespan.
Mid‐ventricular Hypertrophic Obstructive Cardiomyopathy with Apical Aneurysm Complicated with Syncope by Sustained Monomorphic Ventricular Tachycardia
Authors: Pérez‐Riera Andrés Ricardo , Barbosa‐Barros Raimundo , de Lucca Augusto Armando , Viana Mujimbi Jose , de Abreu Luiz Carlos
Published: July 2016

Mid‐ventricular hypertrophic obstructive cardiomyopathy with secondary formation of apical aneurysm is a rare variant of hypertrophic cardiomyopathy. They have a unique behavior because unlike other variants it causes sustained monomorphic ventricular tachycardia, which makes it particularly severe.
Clinical risk management – a 3‐year experience of team timeout in 18 081 ophthalmic patients
Authors: Weingessel Birgit , Haas Michaela , Vécsei Christina , Vécsei‐Marlovits Pia Veronika
Published: July 2016

Purpose

Clinical risk management aims to identify, analyse and avoid errors and risks systematically to improve patient's safety. Preoperative checklists to prevent mistakes have gained importance in the last few years. A so‐called team timeout checklist was introduced in October 2011 at the Department of Ophthalmology, Hietzing Hospital, Vienna. The purpose of the study is to evaluate the benefits and demonstrate the value of team timeout.

Methods

After the team timeout had been in use for 6 months, all near misses that occurred over a period of 34 months were assigned to the following groups: wrong side, wrong lens, wrong patient and miscellaneous.

Results

Eighteen thousand and eighty‐one surgeries were performed in the specified period; 53 cases of ‘wrong side’ and 52 cases of ‘wrong intraocular lens’ were noted. Ninety‐six near misses concerned the patients’ data and 38 concerned documentation. A reduction of near misses was noted after an adaptation phase of 3 months.

Conclusions

Team timeout proved valuable, as it improved the patients' safety with minimum effort. Errors may occur despite several preoperative controls and can be detected by performing team timeout.
Surgical responses and outcomes of bilateral lateral rectus recession in exotropia with cerebral palsy
Authors: Ma Dae Joong , Yang Hee Kyung , Hwang Jeong‐Min
Published: July 2016

Purpose

To determine surgical responses and outcomes of bilateral lateral rectus (BLR) recession in exotropes with cerebral palsy (CP) and to compare the results with exotropes without CP.

Methods

Forty‐one exotropes with CP and 82 age‐ and type (intermittent or constant)‐matched exotropes without CP who underwent BLR recession by one surgeon (J‐M.H.) were evaluated. Main outcome measures were surgical responses, factors affecting surgical response, success rates, cumulative probabilities of success and recurrence, and drifts of ocular alignment towards exodeviation after surgery (exodrift).

Results

The surgical responses of BLR recession were not significantly different between both groups (p = 0.136). After a mean follow‐up period of 2 years, success rates showed no significant difference between the two groups (p = 1.000). The cumulative probabilities of success and recurrence were not significantly different between the two groups (p = 0.770 and 0.754, respectively). The rate of recurrence per person‐year during follow‐up was 16.7% in patients with CP and 20.2% in patients without CP. The amount of exodrift showed no significant difference between both groups (p = 0.118).

Conclusions

Exotropes with CP showed a similar surgical response, an amount of exodrift, cumulative success and recurrence rates after BLR recession compared to exotropes without CP.
Endothelium‐in versus endothelium‐out for Descemet membrane endothelial keratoplasty graft preparation and implantation
Authors: Parekh Mohit , Ruzza Alessandro , Ferrari Stefano , Ahmad Sajjad , Kaye Stephen , Ponzin Diego , Romano Vito
Published: July 2016

Purpose

To evaluate the difference between endothelium‐in and endothelium‐out for Descemet membrane endothelial keratoplasty (DMEK) preparation and implantation using injection method.

Methods

The study was a randomized, comparative, institutional, laboratory investigation. Eighteen human donor corneas were included. A total of 9.5 mm DMEK grafts were stripped and restored on the corneal base with a hinge and preserved in the deswelling medium. The grafts were detached from the hinge and either manually tri‐folded with the endothelium on the inside, or allowed to spontaneously roll in phosphate‐buffered saline (PBS) with endothelium outwards. The corneas were mounted on an artificial anterior chamber (AAC) and four incisions made using a 15° eye knife for the side ports and slit knife to create a 3.0 mm incision for delivery of the graft into the AAC. The grafts with endothelium‐in (endo‐in) were pulled into a cartridge, whereas those with endothelium‐out (endo‐out) were aspirated using a modified Jones tube. Both were delivered using an injection method. Central and peripheral endothelial cell density (pre‐ and post‐delivery and after removal), time of preparation and unfolding were measured.

Results

Endothelial cell loss postimplantation was 10.53% (±2.82) with endo‐in (n = 9) compared to 7.56% (±14.74) with endo‐out (n = 9) (p > 0.05). Preparation and unfolding time was 4.43 min (±3.43) and 0.96 min (±1.10) for endo‐in compared to 1.68 min (±0.57) and 4.92 min (±4.21) for endo‐out. A statistical significance between endo‐in and endo‐out for loading (p = 0.04) and unfolding (p = 0.023) time was observed.

Conclusions

Descemet membrane endothelial keratoplasty tissues can be tri‐folded (endo‐in) with no significantly less cell loss as compared to endo‐out. Spontaneous unfolding of endo‐in may reduce overall time and surgical manipulation.
Malignant pleural mesothelioma with lacrimal gland metastasis
Authors: Hanafi Hanida , Verdijk Rob M. , Paridaens Dion
Published: July 2016

Purpose

To describe a rare clinical case of biopsy‐proven metastatic mesothelioma of the lacrimal gland which responded well to chemo and radiation therapy.

Methods

Interventional case report.

Results

A 55‐year‐old woman with an untreated malignant biopsy‐proven pleural mesothelioma presented with right proptosis, diplopia and hypoglobus. Magnetic resonance imaging showed an aggressive lacrimal gland tumour with bony erosion. A biopsy concluded a diagnosis of metastatic mesothelioma of the lacrimal gland. Her lacrimal and lung tumours showed a marked regression following palliative chemo (carboplatin) and radiation therapy.

Conclusions

Malignant pleural mesothelioma may metastasize to the orbit, including the lacrimal gland. A combined chemo and radiation therapy may reduce the size of the metastatic and primary tumour.
Right services to right patients at right time in right setting in Tays Eye Centre
Authors: Tuulonen Anja , Kataja Marko , Syvänen Ulla , Miettunen Sirpa , Uusitalo Hannu
Published: July 2016

Purpose

The report describes the concepts behind procedures implemented in Tays Eye Centre to enable improved access to care and improved productivity.

Methods

The strategy was developed in 2009 after hospital district decided to construct a new eye hospital which was opened in 2012. The following principles were implemented: (i) identification of high‐volume patient groups: the ‘big four’ eye diseases accounting for 70% of patient visits and costs: age‐related macular degeneration (AMD), glaucoma, retinal diseases and cataract; (ii) stratification and prioritization of patient care based on risk of permanent visual disability; (iii) standardization of services for low‐risk patients; (iv) maximization of productivity; and (v) shared care. The impact of the new strategy on access to care and productivity is reported for years 2011–2015.

Results

In 2011–2015, the total number of services provided increased 46% while the work contribution increased 15%. The number of referrals increased 76% and the number of outpatient appointments increased 2.5‐fold. Simultaneously, the number of delayed follow‐up visits decreased to zero. Age‐related macular degeneration (AMD) injections increased 1.8‐fold. However, after 50% yearly increase in Age‐related macular degeneration (AMD) injections, a plateau was reached in 2014 with a 3% decline in 2014–2015 with no changes in treatment indications. In the beginning of 2016, the number of injections has started to increase again (+9% compared to 2015).

 The total number of surgical procedures increased 98%. The annual number of cataract surgeries increased 64% and bilateral surgeries from 11% to 39%.

Conclusion

Revised operational concepts and new facilities together with a 15% increase in work contribution led to a 46% increase in overall productivity, improved access to care and the clearance of delayed services. Efforts continue to further refine cost‐effective care and to define the appropriate levels of services.
Thermoresponsive Polymers with Lower Critical Solution Temperature‐ or Upper Critical Solution Temperature‐Type Phase Behaviour Do Not Induce Toxicity to Human Endothelial Cells
Authors: Ji Yuejia , Zhu Mengxiang , Gong Yu , Tang Haoyu , Li Juan , Cao Yi
Published: July 2016

Thermoresponsive polymers have gained extensive attention as biomedical materials especially for targeted drug delivery systems. We have recently developed water‐soluble polypeptide‐based thermoresponsive polymers that exhibit lower critical solution temperature (LCST)‐ or upper critical solution temperature (UCST)‐type phase behaviours. In this study, the toxicity of these polymers to human umbilical vein endothelial cells (HUVECs) was investigated to assess the safety and biocompatibility. Up to 100 μg/ml, thermoresponsive polymers did not induce cytotoxicity to HUVECs, showing as unaltered mitochondrial viability assessed as cell counting kit‐8 (CCK‐8) assay and membrane integrity assessed as lactate dehydrogenase (LDH) assay. Inflammatory response, assessed as the release of chemokine‐soluble monocyte chemotactic protein 1 (sMCP‐1) and interleukin‐8 (IL‐8) as well as cytokine IL‐6, was not significantly affected by the polymers. In addition, 1 μM thapsigargin (TG), an endoplasmic reticulum (ER) stress inducer, significantly decreased mitochondrial viability, but did not affect membrane integrity or inflammatory response. The presence of thermoresponsive polymers with LCST‐type phase behaviour did not further affect the effects of TG. In conclusion, the thermoresponsive polymers used in this study are not toxic to endothelial cells and therefore could be further considered as safe materials for biomedical applications.
Technology enhanced teaching and learning in South African higher education – A rearview of a 20 year journey
Authors: Ng'ambi Dick , Brown Cheryl , Bozalek Vivienne , Gachago Daniela , Wood Denise
Published: July 2016

In the last 20 years, the South African higher education has changed significantly, influenced by global trends national development goals and pressure from local educational imperatives, in the context of a digitally networked world. Shifts in technology enhanced pedagogical practices and in discourses around information and communication technologies (ICTs) have had varying degrees of influence in higher education. This paper takes a rearview of a 20‐year journey of technology enhanced learning in South African higher education. An analysis of literature view is presented chronologically in four phases: phase 1 (1996–2000), phase 2 (2001–05), phase 3 (2006–10) and phase 4 (2011–16). In phase 1 technology was used predominantly for drill and practice, computer‐aided instruction, with growing consciousness of the digital divide. In phase 2 institutions primarily focused on building ICT infrastructure, democratizing information, policy development and research; they sought to compare the effectiveness of teaching with or without technology. During phase 3 institutions began to include ICTs in their strategic directions, digital divide debates focused on epistemological access, and they also began to conduct research with a pedagogical agenda. In phase 4 mobile learning and social media came to the fore. The research agenda shifted from whether students would use technology to how to exploit what students already use to transform teaching and learning practices. The paper concludes that South Africa's higher education institutions have moved from being solely responsible for both their own relatively poor ICT infrastructure and education provision to cloud‐based ICT infrastructure with “unlimited” educational resources that are freely, openly and easily available within and beyond the institution. Although mobile and social media are more evident now than ever before, teaching and learning practice in South African higher education remains largely unchanged.
Antagonism of the proinflammatory and pronociceptive actions of canonical and biased agonists of protease‐activated receptor‐2
Authors: Lieu T , Savage E , Zhao P , Edgington‐Mitchell L , Barlow N , Bron R , Poole D P , McLean P , Lohman R‐J , Fairlie D P , Bunnett N W
Published: July 2016

Background and Purpose

Diverse proteases cleave protease‐activated receptor‐2 (PAR2) on primary sensory neurons and epithelial cells to evoke pain and inflammation. Trypsin and tryptase activate PAR2 by a canonical mechanism that entails cleavage within the extracellular N‐terminus revealing a tethered ligand that activates the cleaved receptor. Cathepsin‐S and elastase are biased agonists that cleave PAR2 at different sites to activate distinct signalling pathways. Although PAR2 is a therapeutic target for inflammatory and painful diseases, the divergent mechanisms of proteolytic activation complicate the development of therapeutically useful antagonists.

Experimental Approach

We investigated whether the PAR2 antagonist GB88 inhibits protease‐evoked activation of nociceptors and protease‐stimulated oedema and hyperalgesia in rodents.

Key Results

Intraplantar injection of trypsin, cathespsin‐S or elastase stimulated mechanical and thermal hyperalgesia and oedema in mice. Oral GB88 or par2 deletion inhibited the algesic and proinflammatory actions of all three proteases, but did not affect basal responses. GB88 also prevented pronociceptive and proinflammatory effects of the PAR2‐selective agonists 2‐furoyl‐LIGRLO‐NH2 and AC264613. GB88 did not affect capsaicin‐evoked hyperalgesia or inflammation. Trypsin, cathepsin‐S and elastase increased [Ca2+]i in rat nociceptors, which expressed PAR2. GB88 inhibited this activation of nociceptors by all three proteases, but did not affect capsaicin‐evoked activation of nociceptors or inhibit the catalytic activity of the three proteases.

Conclusions and Implications

GB88 inhibits the capacity of canonical and biased protease agonists of PAR2 to cause nociception and inflammation.
Design, synthesis, and in vitro antimicrobial activity of hydrazide–hydrazones of 2‐substituted acetic acid
Authors: Popiołek Łukasz , Biernasiuk Anna
Published: July 2016

In this study, 30 hydrazide–hydrazones of phenylacetic (3–10) and hydroxyacetic acid (11–32) were synthesized by the condensation reaction of appropriate 2‐substituted acetic acid hydrazide with different aromatic aldehydes. The obtained compounds were characterized by spectral data and evaluated in vitro for their potential antimicrobial activities against a panel of reference strains of micro‐organisms, including Gram‐positive bacteria, Gram‐negative bacteria, and fungi belonging to the Candida spp. The results from our antimicrobial assays indicated that among synthesized compounds 3–32, especially compounds 6, 14, and 26 showed high bactericidal activity (MIC = 0.488–7.81 μg/ml) against reference Gram‐positive bacteria, and in some cases, their activity was even better than that of commonly used antibiotics, such as cefuroxime or ampicillin.
Environmental Contaminants and Child Development
Authors: Trentacosta Christopher J. , Davis‐Kean Pamela , Mitchell Colter , Hyde Luke , Dolinoy Dana
Published: July 2016

Developmental scientists have long been interested in how the environment influences children's development. However, with few exceptions, they have not researched how exposure to contaminants in the physical environment affects developmental processes. Children are uniquely at risk for exposure to contaminants because they drink more, eat more, and breathe more air than adults as a proportion of their body weight. In this article, we provide an ecosystems perspective to illustrate how contexts—from the prenatal environment and neighborhood‐level exposure to laws and policies—contribute to children's exposure to contaminants. We also discuss four mechanisms that account for how and when exposure to contaminants affects children, and we provide examples to spur research on these mechanisms. We conclude with recommendations to foster integrative science where developmental science interacts with environmental health and toxicology.
Combined Magnesium/Polyethylene Glycol Facilitates the Neuroprotective Effects of Magnesium in Traumatic Brain Injury at a Reduced Magnesium Dose
Authors: Busingye Diana S. , Turner Renée J. , Vink Robert
Published: July 2016

Aims

While a number of studies have shown that free magnesium (Mg) decline is a feature of traumatic brain injury (TBI), poor central penetration of Mg has potentially limited clinical translation. This study examines whether polyethylene glycol (PEG) facilitates central penetration of Mg after TBI, increasing neuroprotection while simultaneously reducing the dose requirements for Mg.

Methods

Rats were exposed to diffuse TBI and administered intravenous MgCl2 either alone (254 μmol/kg or 25.4 μmol/kg) or in combination with PEG (1 g/kg PEG) at 30‐min postinjury. Vehicle‐treated (saline or PEG) and sham animals served as controls. All animals were subsequently assessed for blood‐brain barrier permeability and edema at 5 h, and functional outcome for 1 week postinjury.

Results

Optimal dose (254 μmol/kg) MgCl2 or Mg PEG significantly improved all outcome parameters compared to vehicle or PEG controls. Intravenous administration of 10% MgCl2 alone (25.4 μmol/kg) had no beneficial effect on any of the outcome parameters, whereas 10% Mg in PEG had the same beneficial effects as optimal dose Mg administration.

Conclusion

Polyethylene glycol facilitates central penetration of Mg following TBI, reducing the concentration of Mg required to confer neuroprotection while simultaneously reducing the risks associated with high peripheral Mg concentration.
Cerebral Functional Reorganization in Ischemic Stroke after Repetitive Transcranial Magnetic Stimulation: An fMRI Study
Authors: Li Jing , Zhang Xue‐Wei , Zuo Zhen‐Tao , Lu Jie , Meng Chun‐Ling , Fang Hong‐Ying , Xue Rong , Fan Yong , Guan Yu‐Zhou , Zhang Wei‐Hong
Published: July 2016

Aims

Our study aimed to figure out brain functional reorganization evidence after repetitive transcranial magnetic stimulation (rTMS) using the resting‐state functional magnetic resonance imaging (rsfMRI).

Methods

Twelve patients with unilateral subcortex lesion in the middle cerebral artery territory were recruited. Seven of them received a 10‐day rTMS treatment beginning at about 5 days after stroke onset. The remaining five received sham treatment. RsfMRI and motor functional scores were obtained before and after rTMS or sham rTMS.

Results

The rTMS group showed motor recovery according to the behavioral testing scores, while there was no significant difference of motor functional scores in the sham group before and after the sham rTMS. It proved that rTMS facilitates motor recovery of early ischemic stroke patients. Compared with the sham, the rTMS treatment group achieved increased functional connectivity (FC) between ipsilesional M1 and contralesional M1, supplementary motor area, bilateral thalamus, and contralesional postcentral gyrus. And decreased FC was found between ipsilesional M1 and ipsilesional M1, postcentral gyrus and inferior and middle frontal gyrus.

Conclusion

Increased or decreased FC detected by rsfMRI is an important finding to understand the mechanism of brain functional reorganization. The rTMS treatment is a promising therapeutic approach to facilitate motor rehabilitation for early stroke patients.
Are there differences in outcome after elective sigmoidectomy for diverticular disease and for cancer? A national inpatient study
Authors: Ilyas M. I. M. , Zangbar B. , Nfonsam V. N. , Maegawa F. A. , Joseph B. A. , Patel J. A. , Wexner S. D.
Published: July 2016

Aim

The postoperative outcome after elective sigmoidectomy for diverticulitis has not been compared to that for cancer. The study aimed to evaluate the differences in the postoperative outcome after sigmoidectomy for diverticular disease and cancer.

Method

The National Inpatient Sample Database was used to identify patients who underwent elective sigmoid resection for diverticular disease or cancer between 2004 and 2011. After excluding patients with metastatic cancer and preoperative weight loss, sigmoid cancer and diverticulitis patients were matched using propensity score, controlling for age, gender, race, type of operation (open vs laparoscopic) and comorbidities. The end‐points of interest were infective complications, reoperation, anastomotic leakage, rebleeding, length of hospital stay and in‐hospital mortality.

Results

After propensity score matching (diverticulitis 11 192 patients, sigmoid cancer 11 192 patients), the mean age was 65 ± 12.5 years, 53.8% were male and 61.5% were Caucasian. Only 18.0% of the operations were done by laparoscopy. The overall complication rate was 17.7% and the in‐hospital mortality rate was 0.9%. The diverticulitis group had a higher rate of surgical site infection (3.2% vs 2.6%, P = 0.004), intra‐abdominal abscess formation (1.2% vs 0.4%, P < 0.0001) and reoperation (6.1% vs 4.1%, P < 0.0001) compared with the cancer group. The cancer group had a higher incidence of pneumonia (1.9% vs 1.5%, P = 0.01) and anastomotic leakage (9.2% vs 8.3%, P = 0.001). There was no difference in sepsis, deep vein thrombosis, respiratory failure, renal failure, rebleeding, overall complication rate or length of hospital stay. Subgroup analysis showed a higher in‐hospital mortality for cancer than for diverticulitis patients whether resected by open or by laparoscopic surgery.

Conclusion

Although elective sigmoidectomy for diverticular disease has a higher risk of infective complications, elective sigmoidectomy for cancer has a higher risk of anastomotic leakage.
Surgical management of fistulating perianal Crohn's disease: a UK survey
Authors: Lee M. J. , Heywood N. , Sagar P. M. , Brown S. R. , Fearnhead N. S. ,   pCD Collaborators
Published: July 2016

Aim

Around one‐third of patients with Crohn's disease are affected by Crohn's fistula‐in‐ano (pCD). It typically follows a chronic course and patients undergo long‐term medical and surgical therapy. We set out to describe current surgical practice in the management of pCD in the UK.

Method

A survey of surgical management of pCD was designed by an expert group of colorectal surgeons and gastroenterologists. This assessed acute, elective, multidisciplinary and definitive surgical management. A pilot of the questionnaire was undertaken at the 2015 meeting of the Digestive Disease Federation. The survey was refined and distributed nationally through the trainee collaborative networks.

Results

National rollout obtained responses from 133 of 179 surgeons approached (response rate 74.3%). At first operation, 32% of surgeons would always consider drainage of sepsis and 31.1% would place a draining seton. At first elective operation, 66.6% would routinely insert of draining seton, and 84.4% would avoid cutting seton. An IBD multidisciplinary team was available to 87.6% of respondents, although only 25.1% routinely discussed pCD patients. Anti‐tumour necrosis factor‐alpha therapy was routinely considered by 64.2%, although 44.2% left medical management to gastroenterologists. Common definitive procedures were removal of the seton only (70.7%), fistulotomy (57.1%), advancement flap (38.9%), fistula plug (36.4%) and ligation of intersphincteric track (LIFT) procedure (31.8%). Indications for diverting stoma or proctectomy were intractable sepsis, incontinence and poor quality of life.

Conclusion

This survey has demonstrated areas of common practice, but has also highlighted divergent practice including choices of definitive surgery and multimodal management. Practical guidelines are required to support colorectal surgeons in the UK.
Cytomegalovirus infection in high‐risk kidney transplant recipients receiving thymoglobulin induction—a single‐center experience
Authors: Puttarajappa Chethan , Bhattarai Manoj , Mour Girish , Shen Chengli , Sood Puneet , Mehta Rajil , Shah Nirav , Tevar Amit D. , Humar Abhinav , Wu Christine , Hariharan Sundaram
Published: July 2016

Background

The burden of cytomegalovirus infection in CMV high‐risk (donor positive to recipient negative) kidney transplant recipients getting thymoglobulin induction and six months of valganciclovir is not well characterized. Additionally, the role of post‐prophylaxis surveillance remains unclear.

Methods

One‐year observational study of forty‐eight high‐risk CMV kidney transplant recipients transplanted under thymoglobulin between January 2013 and July 2014. All received valganciclovir for six months, followed by monthly CMV PCR for three months.

Results

CMV infection defined as viremia with or without symptoms occurred in 40% (19/48). Of these, 47% (9/19) occurred during prophylaxis, 32% (6/19) during surveillance and 21% (4/19) during post‐surveillance period (9–12 months). Among breakthrough infections, suboptimal valganciclovir dosing was present in 55% (5/9). With routine surveillance, there was a trend toward lower CMV‐related hospitalization (17% vs 56% and 75% during prophylaxis and post‐surveillance, respectively [P=.23]) and lower mean peak viral loads (19 432 copies/mL vs 97 925 copies/mL and 536 021 copies/mL during prophylaxis and post‐surveillance, respectively [P=.07]).

Conclusion

CMV infection remains a significant problem with thymoglobulin induction despite six months of valganciclovir. Suboptimal valganciclovir dosing was common among breakthrough infections. Monthly surveillance post‐prophylaxis appears to detect early CMV infection with lower degree of viremias requiring fewer hospitalizations.
Improving graft survival by understanding the mechanism of segment 4 complications after split liver transplantation
Authors: Komatsu Shohei , Vicentine Fernando Pompeu Piza , El Mouhadi Sanaâ , Brustia Raffaele , Perdigao Fabiano , Sepulveda Ailton , Soubrane Olivier , Scatton Olivier
Published: July 2016

Background

This study was designed to assess the actual mechanism of segment 4 (S4)‐related complications after split liver transplantation (SLT) and their impact on graft and overall survival with reference to those of left lateral sectionectomy for pediatric living donor liver transplantation (LLSLD).

Methods

Clinical data from 53 SLT recipients and 62 LLSLD patients were assessed to determine the mechanism of S4‐related complications. The postoperative parameters of SLT and their impact on graft and overall survival were also evaluated.

Results

Although two biliary leakages were noted (3.2%), no necrosis of S4 developed after LLSLD. S4‐related complications were seen in 15 (28.3%) patients after SLT. Radiological volumetry of S4 and the ischemic area after SLT showed no significant difference between those with and without S4‐related complications. There were no significant differences between the patients with and without S4‐related complications regarding both overall and graft survival rates. Significant better overall and graft survival rates were observed in patients treated during the later period.

Conclusions

S4‐related complications after SLT are totally independent of the S4 volume, and biliary leakage is inherently an actual mechanism. Adequate intervention with early identification leads to better graft and overall survival, which validates SLT as a treatment option.
Long‐term outcomes of infective encephalitis in children: a systematic review and meta‐analysis
Authors: Khandaker Gulam , Jung Jenny , Britton Philip N , King Catherine , Yin J Kevin , Jones Cheryl A
Published: July 2016

Aim

The long‐term outcomes of childhood infective encephalitis are variable and not well quantified. We aimed to systematically review the literature and undertake meta‐analyses on predetermined outcomes to address this knowledge gap and identify areas for future research.

Method

We searched electronic databases, performed complementary reviews of references of fully extracted articles, and made contact with experts on infective encephalitis. Articles published up until April 2016 were selected for screening.

Results

We evaluated sequelae of 1018 survivors of childhood infective encephalitis (934 with complete follow‐up) from 16 studies. Mean age during acute encephalitis episodes was 5 years 3.6 months (range 1.2mo–17y), 57.6% were male (500/868), and mean follow‐up period was 4 years 1.2 months (range 1–12y). Incomplete recovery was reported in 312 children (42.0%; 95% confidence interval [CI] 31.6–53.1% in pooled estimate). Among the other sequelae, developmental delay, abnormal behaviour, motor impairment, and seizures were reported among 35.0% (95% CI 10.0–65.0%), 18.0% (95% CI 8.0–31.0%), 17.0% (95% CI 10.0–26.0%), and 10.0% (95% CI 6.0–14.0%) respectively.

Interpretation

Almost half of childhood infective encephalitis survivors report incomplete recovery in the long‐term; most commonly developmental delay, behavioural abnormality, and neurological impairments (i.e. seizure). Well designed, large‐scale prospective studies are needed to better quantify neurodevelopmental sequelae among childhood encephalitis survivors.
Cerebral palsy is associated with an elevated risk of stroke throughout life: evidence from Taiwan
Authors: Day Steven M
Published: July 2016

This commentary is on the original article by Wu et al. on pages 52–56 of this issue.
Measuring functional ability of autism spectrum disorder in a global context
Authors: de Vries Petrus J , Bölte Sven
Published: July 2016

This commentary is on the original article by Di Rezze et al. on pages 942–948 of this issue.
The relation between mirror movements and non‐use of the affected hand in children with unilateral cerebral palsy
Authors: Zielinski Ingar M , Green Dido , Rudisch Julian , Jongsma Marijtje L A , Aarts Pauline B M , Steenbergen Bert
Published: July 2016

Aim

In children with unilateral cerebral palsy (CP), it is widely believed that mirror movements contribute to non‐use of the affected hand despite preserved capacity, a phenomenon referred to as developmental disregard. We aimed to test whether mirror movements are related to developmental disregard, and to clarify the relation between mirror movements and bimanual function.

Method

A repetitive squeezing task simultaneously measuring both hands' grip‐forces was developed to assess mirror movements by using maximum cross‐correlation coefficient (CCCmax) as well as strength measures (MMstrength). Developmental disregard, bimanual performance, and capacity were assessed using a validated video‐observation method. Twenty‐one children with unilateral CP participated (Median age 10y 7mo, interquartile range [IQR] 10y 1mo–12y 9mo). Outcome measures of mirror movements were correlated to developmental disregard, bimanual performance, and capacity scores using Spearman's correlations (significance level: α<0.05).

Results

Mirror movements were not related to developmental disregard. However, enhanced mirror movements in the less‐affected hand were related to reduced performance (CCCmax: ρ=−0.526, p=0.007; MMstrength: ρ=−0.750, p<0.001) and capacity (CCCmax: ρ=−0.410, p=0.033; MMstrength: ρ=−0.679, p<0.001). These relations were only moderate (performance:MMstrength: ρ=−0.504, p=0.010), low (capacity: MMstrength: ρ=−0.470, p=0.016) or absent for mirror movements in the affected hand. Additionally, seven children showed stronger movements in their less‐affected hands when actually being asked to move their affected hand.

Interpretation

These findings show no relation between mirror movements and developmental disregard, but support an association between mirror movements and bimanual function.
Prevalence of specific gait abnormalities in children with cerebral palsy revisited: influence of age, prior surgery, and Gross Motor Function Classification System level
Authors: Rethlefsen Susan A , Blumstein Gideon , Kay Robert M , Dorey Frederick , Wren Tishya A L
Published: July 2016

Aim

To examine the impact of age, surgery, and Gross Motor Function Classification System (GMFCS) level on the prevalence of gait problems in children with cerebral palsy (CP).

Method

Gait analysis records were retrospectively reviewed for ambulatory patients with CP. Gait abnormalities were identified using physical exam and kinematic data. Relationships among age, sex, previous surgery, GMFCS level, and prevalence of gait abnormalities associated with crouch and out‐toeing, and equinus and in‐toeing were assessed using univariable and multivariable logistic regression.

Results

One‐thousand and five records were reviewed. The most common gait problems were in‐toeing, excessive knee flexion, stiff knee, hip flexion, internal rotation, adduction, and equinus (all >50%). Odds ratios (OR) for various gait problems associated with crouch and out‐toeing increased (OR 1.07–1.32), and those associated with equinus and in‐toeing decreased (OR 0.80–0.94) significantly with increasing age for patients in GMFCS levels I to III. The same trends were seen with prior surgery (OR for crouch and out‐toeing: 1.86–7.14; OR for equinus and in‐toeing: 0.16–0.59).

Interpretation

The prevalence of gait abnormalities varies by GMFCS level, but similarities exist among levels. The study results suggest that in younger children, particularly those in GMFCS levels III and IV, treatments for equinus and in‐toeing should be undertaken with caution because these problems tend to decrease with age even without orthopedic intervention. Such children may end up with the ‘opposite’ deformities of calcaneal crouch and out‐toeing, which tend to increase in prevalence with age.
Non‐native rainbow trout (Oncorhynchus mykiss) occupy a different trophic niche to native Breede River redfin (Pseudobarbus burchelli) which they replace in South African headwater streams
Authors: Shelton Jeremy M. , Bird Matthew S. , Samways Michael J. , Day Jenny A.
Published: July 2016

Recent research has revealed that non‐native rainbow trout Oncorhynchus mykiss have largely replaced a native cyprinid, the Breede River redfin Pseudobarbus burchelli, as the dominant species of fish in many headwater streams in the Cape Floristic Region (CFR) of South Africa. Moreover, differences in the composition of benthic communities in CFR headwater streams with and without trout suggest that trout do not functionally compensate for the native redfin which they have replaced in these food webs. In this study, we used gut content and stable isotope analyses to characterise and compare the trophic niches and diet compositions of allopatric populations of trout and redfin in six CFR headwater streams (three containing trout, three containing redfin). Results indicate that native redfin exploit a broader trophic niche, and a more omnivorous diet, than do trout. Gut content analyses showed terrestrial invertebrates to be an important prey source for trout, which could potentially offset predation pressure on aquatic invertebrates and explain why benthic invertebrate density in streams with trout is higher than that in streams with no trout. Contrastingly, redfin diet appeared to be dominated by aquatic invertebrates, with terrestrial prey a less important food item in the guts of redfin. That redfin and trout exploit nonequivalent trophic niches may have consequences for benthic community composition in CFR headwater streams, and this study highlights the importance of quantifying how the functional role of predators changes following a predator replacement for understanding and managing the consequences of non‐native predator invasions.