Multi-omics for studying and understanding polar life.

Polar ecosystems are experiencing amongst the most rapid rates of regional warming on Earth. Here, we discuss 'omics' approaches to investigate polar biodiversity, including the current state of the art, future perspectives and recommendations. We propose a community road map to generate and more fully exploit multi-omics data from polar organisms. These data are needed for the comprehensive evaluation of polar biodiversity and to reveal how life evolved and adapted to permanently cold environments with extreme seasonality. We argue that concerted action is required to mitigate the impact of warming on polar ecosystems via conservation efforts, to sustainably manage these unique habitats and their ecosystem services, and for the sustainable bioprospecting of novel genes and compounds for societal gain.

Relationship between Shear Stiffness Measured by MR Elastography and Perfusion Metrics Measured by Perfusion CT of Meningiomas.

BACKGROUND AND PURPOSE: When managing meningiomas, intraoperative tumor consistency and histologic subtype are indispensable factors influencing operative strategy. The purposes of this study were the following: 1) to investigate the correlation between stiffness assessed with MR elastography and perfusion metrics from perfusion CT, 2) to evaluate whether MR elastography and perfusion CT could predict intraoperative tumor consistency, and 3) to explore the predictive value of stiffness and perfusion metrics in distinguishing among histologic subtypes of meningioma. MATERIALS AND METHODS: Mean tumor stiffness and relative perfusion metrics (blood flow, blood volume, and MTT) were calculated (relative to normal brain tissue) for 14 patients with meningiomas who underwent MR elastography and perfusion CT before surgery (cohort 1). Intraoperative tumor consistency was graded by a neurosurgeon in 18 patients (cohort 2, comprising the 14 patients from cohort 1 plus 4 additional patients). The correlation between tumor stiffness and perfusion metrics was evaluated in cohort 1, as was the ability of perfusion metrics to predict intraoperative tumor consistency and discriminate histologic subtypes. Cohort 2 was analyzed for the ability of stiffness to determine intraoperative tumor consistency and histologic subtypes. RESULTS: The relative MTT was inversely correlated with stiffness (P = .006). Tumor stiffness was positively correlated with intraoperative tumor consistency (P = .01), while perfusion metrics were not. Relative MTT significantly discriminated transitional meningioma from meningothelial meningioma (P = .04), while stiffness did not significantly differentiate any histologic subtypes. CONCLUSIONS: In meningioma, tumor stiffness may be useful to predict intraoperative tumor consistency, while relative MTT may potentially correlate with tumor stiffness and differentiate transitional meningioma from meningothelial meningioma.

Paid employment and common mental disorders in 50-64-year olds: analysis of three cross-sectional nationally representative survey samples in 1993, 2000 and 2007.

AIMS: Associations between employment status and mental health are well recognised, but evidence is sparse on the relationship between paid employment and mental health in the years running up to statutory retirement ages using robust mental health measures. In addition, there has been no investigation into the stability over time in this relationship: an important consideration if survey findings are used to inform future policy. The aim of this study is to investigate the association between employment status and common mental disorder (CMD) in 50-64-year old residents in England and its stability over time, taking advantage of three national mental health surveys carried out over a 14-year period. METHODS: Data were analysed from the British National Surveys of Psychiatric Morbidity of 1993, 2000 and 2007. Paid employment status was the primary exposure of interest and CMD the primary outcome - both ascertained identically in all three surveys (CMD from the revised Clinical Interview Schedule). Multivariable logistic regression models were used. RESULTS: The prevalence of CMD was higher in people not in paid employment across all survey years; however, this association was only present for non-employment related to poor health as an outcome and was not apparent in those citing other reasons for non-employment. Odds ratios for the association between non-employment due to ill health and CMD were 3.05 in 1993, 3.56 in 2000, and 2.80 in 2007, after adjustment for age, gender, marital status, education, social class, housing tenure, financial difficulties, smoking status, recent physical health consultation and activities of daily living impairment. CONCLUSIONS: The prevalence of CMD was higher in people not in paid employment for health reasons, but was not associated with non-employment for other reasons. Associations had been relatively stable in strength from 1993 to 2007 in those three cross-sectional nationally representative samples.

Comparison of structural, thermal and proton conductivity properties of micro- and nanocelluloses.

Our search for a cellulose-based proton conducting material is continued. This paper presents selected physicochemical properties of cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs) together with cellulose microcrystals (CMCs) and cellulose microfibrils (CMFs), determined by X-ray diffraction (XRD), thermogravimetric analysis (TGA + DTA), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FT-IR), and electrical impedance spectroscopy (EIS). The CNCs and CNFs were studied in the forms of powder and film. They were produced in the process of transition metal catalyzed oxidative process or by TEMPO-mediated oxidation. It has been shown that regardless of the production method and the form of the sample the celluloses retained the cellulose Iß crystalline structure, the cellulose films showed similar thermal properties in the relevant temperature range from room temperature to about 200 °C, and the TEMPO-oxidized CNF film showed the highest proton conductivity when compared with those of the other samples studied.

Waveguide effects and implications for cardiac magnetic resonance elastography: A finite element study.

Magnetic resonance elastography (MRE) is increasingly being applied to thin or small structures in which wave propagation is dominated by waveguide effects, which can substantially bias stiffness results with common processing approaches. The purpose of this work was to investigate the importance of such biases and artifacts on MRE inversion results in: (i) various idealized 2D and 3D geometries with one or more dimensions that are small relative to the shear wavelength; and (ii) a realistic cardiac geometry. Finite element models were created using simple 2D geometries as well as a simplified and a realistic 3D cardiac geometry, and simulated displacements acquired by MRE from harmonic excitations from 60 to 220 Hz across a range of frequencies. The displacement wave fields were inverted with direct inversion of the Helmholtz equation with and without the application of bandpass filtering and/or the curl operator to the displacement field. In all geometries considered, and at all frequencies considered, strong biases and artifacts were present in inversion results when the curl operator was not applied. Bandpass filtering without the curl was not sufficient to yield accurate recovery. In the 3D geometries, strong biases and artifacts were present in 2D inversions even when the curl was applied, while only 3D inversions with application of the curl yielded accurate recovery of the complex shear modulus. These results establish that taking the curl of the wave field and performing a full 3D inversion are both necessary steps for accurate estimation of the shear modulus both in simple thin-walled or small structures and in a realistic cardiac geometry when using simple inversions that neglect the hydrostatic pressure term. In practice, sufficient wave amplitude, signal-to-noise ratio, and resolution will be required to achieve accurate results.

MR Elastography Analysis of Glioma Stiffness and IDH1-Mutation Status.

BACKGROUND AND PURPOSE: Our aim was to noninvasively evaluate gliomas with MR elastography to characterize the relationship of tumor stiffness with tumor grade and mutations in the isocitrate dehydrogenase 1 (IDH1) gene. MATERIALS AND METHODS: Tumor stiffness properties were prospectively quantified in 18 patients (mean age, 42 years; 6 women) with histologically proved gliomas using MR elastography from 2014 to 2016. Images were acquired on a 3T MR imaging unit with a vibration frequency of 60 Hz. Tumor stiffness was compared with unaffected contralateral white matter, across tumor grade, and by IDH1-mutation status. The performance of the use of tumor stiffness to predict tumor grade and IDH1 mutation was evaluated with the Wilcoxon rank sum, 1-way ANOVA, and Tukey-Kramer tests. RESULTS: Gliomas were softer than healthy brain parenchyma, 2.2 kPa compared with 3.3 kPa (P < .001), with grade IV tumors softer than grade II. Tumors with an IDH1 mutation were significantly stiffer than those with wild type IDH1, 2.5 kPa versus 1.6 kPa, respectively (P = .007). CONCLUSIONS: MR elastography demonstrated that not only were gliomas softer than normal brain but the degree of softening was directly correlated with tumor grade and IDH1-mutation status. Noninvasive determination of tumor grade and IDH1 mutation may result in improved stratification of patients for different treatment options and the evaluation of novel therapeutics. This work reports on the emerging field of "mechanogenomics": the identification of genetic features such as IDH1 mutation using intrinsic biomechanical information.

Order-disorder phase transition in an anhydrous pyrazole-based proton conductor: the enhancement of electrical transport properties.

The crystal structure of 1H-pyrazol-2-ium hydrogen oxalate has been studied at 100 K. It consists of two-dimensional layers built with one-dimensional chains that contain pyrazolium and oxalate acids bonded by N-HO and O-HO hydrogen bonds. According to the X-ray data and the Quantum Theory of Atoms in Molecules, it was shown that weak and moderate hydrogen bonds are present in the crystal at room temperature. The thermal stability was studied with the DSC, TGA, and DTG methods: three endothermic peaks are observed at 384, 420, and 469 K. Conductivity measurements have been performed in the temperature range from 300 to 433 K. At 383 K the pyrazole-oxalic acid framework loses its rigidity and the crystal undergoes an ordered-disordered phase transition. At this temperature, the value of the activation energy of proton conductivity changes from 1.14 to 2.31 eV. The proton conduction pathways and the transport mechanism have been studied with theoretical methods.

Predicting the diagnosis of autism in adults using the Autism-Spectrum Quotient (AQ) questionnaire.

BACKGROUND: Many adults with autism spectrum disorder (ASD) remain undiagnosed. Specialist assessment clinics enable the detection of these cases, but such services are often overstretched. It has been proposed that unnecessary referrals to these services could be reduced by prioritizing individuals who score highly on the Autism-Spectrum Quotient (AQ), a self-report questionnaire measure of autistic traits. However, the ability of the AQ to predict who will go on to receive a diagnosis of ASD in adults is unclear. METHOD: We studied 476 adults, seen consecutively at a national ASD diagnostic referral service for suspected ASD. We tested AQ scores as predictors of ASD diagnosis made by expert clinicians according to International Classification of Diseases (ICD)-10 criteria, informed by the Autism Diagnostic Observation Schedule-Generic (ADOS-G) and Autism Diagnostic Interview-Revised (ADI-R) assessments. RESULTS: Of the participants, 73% received a clinical diagnosis of ASD. Self-report AQ scores did not significantly predict receipt of a diagnosis. While AQ scores provided high sensitivity of 0.77 [95% confidence interval (CI) 0.72-0.82] and positive predictive value of 0.76 (95% CI 0.70-0.80), the specificity of 0.29 (95% CI 0.20-0.38) and negative predictive value of 0.36 (95% CI 0.22-0.40) were low. Thus, 64% of those who scored below the AQ cut-off were 'false negatives' who did in fact have ASD. Co-morbidity data revealed that generalized anxiety disorder may 'mimic' ASD and inflate AQ scores, leading to false positives. CONCLUSIONS: The AQ's utility for screening referrals was limited in this sample. Recommendations supporting the AQ's role in the assessment of adult ASD, e.g. UK NICE guidelines, may need to be reconsidered.

Six-year follow-up study of combined type ADHD from childhood to young adulthood: Predictors of functional impairment and comorbid symptoms.

BACKGROUND: ADHD in childhood is associated with development of negative psychosocial and behavioural outcomes in adults. Yet, relatively little is known about which childhood and adulthood factors are predictive of these outcomes and could be targets for effective interventions. To date follow-up studies have largely used clinical samples from the United States with children ascertained at baseline using broad criteria for ADHD including all clinical subtypes or the use of DSM III criteria. AIMS: To identify child and adult predictors of comorbid and psychosocial comorbid outcomes in ADHD in a UK sample of children with DSM-IV combined type ADHD. METHOD: One hundred and eighteen adolescents and young adults diagnosed with DSM-IV combined type ADHD in childhood were followed for an average of 6years. Comorbid mental health problems, drug and alcohol use and police contact were compared for those with persistent ADHD, sub-threshold ADHD and population norms taken from the Adult Psychiatric Morbidity Study 2007. Predictors included ADHD symptomology and gender. RESULTS: Persistent ADHD was associated with greater levels of anger, fatigue, sleep problems and anxiety compared to sub-threshold ADHD. Comorbid mental health problems were predicted by current symptoms of hyperactivity-impulsivity, but not by childhood ADHD severity. Both persistent and sub-threshold ADHD was associated with higher levels of drug use and police contact compared to population norms. CONCLUSIONS: Young adults with a childhood diagnosis of ADHD showed increased rates of comorbid mental health problems, which were predicted by current levels of ADHD symptoms. This suggests the importance of the continuing treatment of ADHD throughout the transitional years and into adulthood. Drug use and police contact were more common in ADHD but were not predicted by ADHD severity in this sample.

Outbreak of multidrug-resistant Escherichia coli sequence type 131 in a neonatal intensive care unit: efficient active surveillance prevented fatal outcome.

BACKGROUND: Outbreaks of infections with multidrug-resistant bacteria in neonatal intensive care units (NICUs) pose a major threat, especially to extremely preterm infants. This study describes a 35-day outbreak of multidrug-resistant Escherichia coli (E. coli) in a tertiary-level NICU in Germany. AIM: To underline the importance of surveillance policies in the particularly vulnerable cohort of preterm infants and to describe the efficacy of outbreak control strategies. METHODS: Data were collected retrospectively from medical reports. Infants and environment were tested for E. coli. FINDINGS: The outbreak affected a total of 13 infants between 25(+1) and 35(+0) weeks of gestation with seven infants showing signs of infection. The outbreak strain was identified as E. coli sequence type 131. Environmental screening provided no evidence for an environmental source. Through colonization surveillance and immediate and adequate treatment of potentially infected preterm infants, no fatalities occurred. Outbreak control was achieved by strict contact precautions, enhanced screening and temporary relocation of the NICU. Relocation and reconstruction improved the NICU's structural layout, focusing on isolation capacities. Follow-up indicated carriage for several months in some infants. CONCLUSION: Routine surveillance allowed early detection of the outbreak. The identification of carriers of the outbreak strain was successfully used to direct antibiotic treatment in case of infection. Enhanced hygienic measures and ward relocation were instrumental in controlling the outbreak.

MR Elastography Demonstrates Increased Brain Stiffness in Normal Pressure Hydrocephalus.

BACKGROUND AND PURPOSE: Normal pressure hydrocephalus is a reversible neurologic disorder characterized by a triad of cognitive impairment, gait abnormality, and urinary incontinence that is commonly treated with ventriculoperitoneal shunt placement. However, multiple overlapping symptoms often make it difficult to differentiate normal pressure hydrocephalus from other types of dementia, and improved diagnostic techniques would help patient management. MR elastography is a novel diagnostic tool that could potentially identify patients with normal pressure hydrocephalus. The purpose of this study was to assess brain stiffness changes in patients with normal pressure hydrocephalus compared with age- and sex-matched cognitively healthy individuals. MATERIALS AND METHODS: MR elastography was performed on 10 patients with normal pressure hydrocephalus and 21 age- and sex-matched volunteers with no known neurologic disorders. Image acquisition was conducted on a 3T MR imaging scanner. Shear waves with 60-Hz vibration frequency were transmitted into the brain by a pillowlike passive driver. A novel postprocessing technique resistant to noise and edge artifacts was implemented to determine regional brain stiffness. The Wilcoxon rank sum test and linear regression were used for statistical analysis. RESULTS: A significant increase in stiffness was observed in the cerebrum (P = .001), occipital lobe (P < .001), parietal lobe (P = .001), and the temporal lobe (P = .02) in the normal pressure hydrocephalus group compared with healthy controls. However, no significant difference was noted in other regions of the brain, including the frontal lobe (P = .07), deep gray and white matter (P = .43), or cerebellum (P = .20). CONCLUSIONS: This study demonstrates increased brain stiffness in patients with normal pressure hydrocephalus compared with age- and sex-matched healthy controls; these findings should motivate future studies investigating the use of MR elastography for this condition and the efficacy of shunt therapy.

An 8-month history of meningitis in an extremely low birth weight infant? - Long-lasting Infection with Ureaplasma parvum.

INTRODUCTION: Ureaplasma spp. have been implicated in the pathogenesis of both preterm labor and neonatal morbidity including pneumonia and sepsis and the development of chronic lung disease of prematurity. Data on Ureaplasma meningitis are limited and partly controversially discussed. PATIENT: We report the unique case of a 9-month-old infant with progressive internal hydrocephalus of unknown origin and developmental delay due to a history of>200 days of inflammation of the central nervous system. The female extremely low birth weight infant had been referred to our hospital for ventriculoperitoneal shunt implantation. She had been born at 26+3 weeks of gestation with a birth weight of 940 g. With the exception of a moderate respiratory distress syndrome, postnatal period had been reported uneventful. However, internal hydrocephalus had become manifest at 4 weeks of postnatal age. Intraventricular hemorrhage had not been documented by cranial ultrasound and magnetic resonance imaging. Cerebrospinal fluid (CSF) analysis had repetitively revealed pronounced inflammation reflected by pleocytosis (50-86 leukocytes/µL, 60% lymphocytes), CSF protein levels of 578-1,026 mg/dL and undetectable CSF glucose. Although suggesting bacterial meningitis, microbial diagnostics had not been indicative, and empirical antibiotics had not affected the CSF findings. On admission to our hospital, CSF analysis still documented significant inflammation (125 leukocytes/µL, CSF protein 565 mg/dL, CSF glucose<2 mg/dL). RESULTS: Due to a prenatal history of cerclage, we initiated microbial diagnostics on Ureaplasma spp. and Mycoplasma hominis. U. parvum was detected in CSF by culture and PCR, no other pathogens were isolated. On intravenous treatment with chloramphenicol, CSF profile continuously normalized, and cultures and PCR became negative. Treatment was continued for 3 weeks, and the infant was discharged after uncomplicated ventriculoperitoneal shunt placement. During a 12-month observation period she has shown encouraging recovery. CONCLUSION: In preterm infants, in particular, internal hydrocephalus of unknown origin and sustained CSF inflammation are highly suggestive of Ureaplasma meningitis. Our case highlights that infection may escape detection if not explicitly considered, since microbial diagnosis requires complex media and PCR.

The impact of atraumatic fibrin sealant vs. staple mesh fixation in TAPP hernia repair on chronic pain and quality of life: results of a randomized controlled study.

BACKGROUND: Mesh reinforcement has become the standard of care in the open and laparoscopic repair of inguinal hernia. Chronic pain after inguinal hernia repair is often due to nerve injury by penetrating mesh fixation devices such as staples (ST), tacks, or sutures. In several studies on hernioplasty, atraumatic mesh fixation with fibrin sealant (FS) proved to be efficient in terms of fixation strength and elasticity. Unfortunately, most of these studies did not provide a standardized follow-up and assessment of the development of chronic pain (CP) and the quality of life (QoL). Therefore, a randomized controlled trial comparing CP and QoL after FS fixation of mesh with ST in transabdominal preperitoneal hernioplasty (TAPP) was performed at our department. The primary end point of our study was to assess the patient outcome by using a visual analog scale (VAS) and the short form 36 (SF-36). The evaluation of recurrence rates was the secondary aim. METHODS: According to the randomization, a macroporous mesh (TiMESH(®)) was fixed in group A (44 patients with 54 inguinal hernias) with FS (TISSEEL) or in group B (45 patients with 56 inguinal hernias) with ST (EMS(®) Stapler). The observation period was 1 year with regular clinical check ups and assessment of VAS and SF-36. RESULTS: Patient characteristics expressed by BMI, ASA scores, and Schumpelick hernia classification were similar in both treatment groups. In each group there was one recurrence within 8 (FS) and 9 months (ST) postsurgery. The mean preoperative pain values scored by VAS were 1.7 (range = 0-7.5) in the FS group and 2.2 (range = 0-6) in the ST group. Postoperative mean VAS scores measured at 1 year postsurgery were 0.4 (range = 0-3) in the FS group and 0.9 (range = 0-7.5) in the ST group. One year postsurgery there was no significant difference between the two groups with respect to the parameter pain in the SF-36 and VAS. CONCLUSION: Fibrin sealant fixation leads to a low rate of hernia recurrence and avoids tissue trauma. ST provide similar results in the hand of the expert but bear inherent risks of complications due to tissue perforation.

Effects of Toxoplasma gondii genotype and absence of host MAL/Myd88 on the temporal regulation of gene expression in infected microglial cells.

The majority of strains of Toxoplasma gondii belong to three distinct clonal lines known as types I, II, and III. The outcome of the immune response to infection is influenced by the parasite strain type. The goal of this study was to examine differences in the kinetics of gene expression in microglial cells infected with types I, II, or III of T. gondii. In addition, a requirement for the integrity of host Toll-like receptor (TLR) signaling in parasite-mediated changes in gene expression was evaluated. Wild type murine microglial cells infected with T. gondii displayed different kinetic patterns of pro-inflammatory cytokine expression that were dependent on the parasite strain type. In general, types II and III elicited higher sustained responses compared to type I which induced fluctuating patterns of cytokine gene expression. Contrary to this, differences in the induction of anti-apoptotic gene expression were minimal among the different type strains throughout infection. Experiments with cells lacking the TLR adaptor molecules MAL and Myd88 showed a dependency on these factors for the pro-inflammatory response but not the anti-apoptotic response. The results show that the outcome of gene expression in T. gondii-infected microglial cells is dependent on the parasite strain type in a time-dependent manner and is selective to particular subsets of genes. The induction of an anti-apoptotic response by T. gondii infection in the absence of TLR signaling reflects a complex level of modulation of host functions by the parasite.

FT NIR Raman studies of alginic acid-benzimidazole polymer composite.

New bio-inspired polymer composites of alginic acid and benzimidazole were created and characterized by FT NIR Raman spectroscopy. The obtained films with 1:0.5, 1:1 and 1:1.5 molar ratio are homogeneous, with good mechanical properties. Raman spectra recorded at room temperature revealed that the obtained films are a new compound with a different molecular structure and physical properties compared with pure substrates: alginic acid and benzimidazole. Raman band related to vibration of COOH entity at 1740 cm(-1) of alginic acid disappears in the alginic acid:benzimidazole composites, in which new Raman band related to COO(-) was found. Additionally, characteristic lines observed in polymer composites which may be associated with vibrations of NH groups, can be attributed to the linking of proton to deprotonated N atom in benzimidazole group. Possibility of such proton exchange is a promising property which might facilitate the application of obtained composites to anhydrous proton conducting electrolytes in fuel cells.

Collagen implants in inguinal and ventral hernia repair.

Collagen has been used in various medical fields and more recently serves as matrix for biomeshes in hernia repair. Meshes derived from organic sources have been designed to reduce foreign body reaction, seromas, adhesions, limited integration, and mesh infection that are frequently found with synthetic meshes. However, synthetic meshes made from polymer materials, e.g., polypropylene or polyester represent the standard of care in both open and laparoscopic inguinal and ventral hernia repair. This review aims to outline the current state of collagen implants and to investigate their potential to replace or compete with synthetic products. Unfortunately, literature reveals a discrepancy between cautious reports and a growing number of acclaiming studies. Special attention has therefore been paid to experimental data of adequate animal models, providing second look data and histology.