The mitral to aortic/pulmonary velocity-time integral ratio is a simple, feasible and accurate discriminator for echocardiographic evaluation of severe isolated mitral regurgitation

Background

Echocardiographic quantification of mitral regurgitation (MR) remains challenging, requiring dedicated image acquisition, and is limited by potential error from geometric assumptions of annular dimensions. Volume is a product of area and flow and assuming proportional mitral/aortic areas, an increased mitral-inflow volume compared to LV/RV-outflow semi-quantitatively represents greater MR regurgitant volume. Therefore, we investigated the feasibility and diagnostic performance of the mitral-aortic velocity-time integral (VTI) ratio in isolated MR. We also investigated the use of the mitral-pulmonary VTI ratio as an alternative in clinical situations where the LV outflow tract (LVOT) VTI could not be used.

Methods

We reviewed 166 consecutive patients (54 (33% severe MR by multi-parameter integrated expert opinion)). Pulsed-Doppler VTI at the mitral leaflet tips and the left ventricular outflow and continuous-wave Doppler of the right ventricular outflow tract were measured individually and independently by blinded readers (expert and trainee status) to derive the ratio. Receiver operator characteristic area under the curve (AUC) comparison was calculated and compared with effective regurgitant orifice area (EROA >40 mm), regurgitant volume (RVol >6 0mL), vena contracta (VC >0.7 cm), E-velocity >1.2 cm, systolic flow reversal (SFR), left atrial and ventricular dilatation.

Results

Increasing ratio was associated with severe MR (AUC 0.94) with optimal threshold defined at 1.3. This provided significant discrimination for severe MR (AUC 0.81) compared to EROA (0.68), VC (0.52), LV dilatation (0.69), LA dilatation (0.70), SFR (0.73), E-velocity (0.68) all p<0.05, with sensitivity 82% and specificity 94%. The mitral-pulmonary VTI ratio demonstrated similar discrimination (AUC 0.92) with optimal threshold defined at 1.14. Excellent inter-observer reproducibility (intra-class correlation 0.97) was seen between trainee and expert readers. There was no difference in AUC comparison by MR mechanism or patient rhythm.

Conclusions

The mitral-aortic or mitral-pulmonary VTI ratio is a simple, geometric-free parameter feasibly reproducible from routine echocardiographic datasets and is an excellent discriminative tool for severe MR. Readers should consider integration of this parameter in routine reporting.

Funding Acknowledgement

Type of funding sources: None.

The Landé factors of electrons and holes in lead halide perovskites: universal dependence on the band gap

The Landé or g-factors of charge carriers are decisive for the spin-dependent phenomena in solids and provide also information about the underlying electronic band structure. We present a comprehensive set of experimental data for values and anisotropies of the electron and hole Landé factors in hybrid organic-inorganic (MAPbI₃, MAPb(Br_0.5Cl_0.5)₃, MAPb(Br_0.05Cl_0.95)₃, FAPbBr₃, FA_0.9Cs_0.1PbI_2.8Br_0.2, MA=methylammonium and FA=formamidinium) and all-inorganic (CsPbBr₃) lead halide perovskites, determined by pump-probe Kerr rotation and spin-flip Raman scattering in magnetic fields up to 10 T at cryogenic temperatures. Further, we use first-principles density functional theory (DFT) calculations in combination with tight-binding and k ⋅ p approaches to calculate microscopically the Landé factors. The results demonstrate their universal dependence on the band gap energy across the different perovskite material classes, which can be summarized in a universal semi-phenomenological expression, in good agreement with experiment.

The Landé factors govern all the spin-related basic phenomena and are the key parameters which guide spintronics applications. Here, Kirstein et al. demonstrate a universal dependence of the Landé factors on the bandgap energy of several perovskite materials.

Neue Terminologie für Sprachentwicklungsstörungen?

Hintergrund

Sprachtherapeutisch-linguistische Fachkreise empfehlen die Anpassung einer von einem internationalen Konsortium empfohlenen Änderung der Nomenklatur für Sprachstörungen im Kindesalter, insbesondere für Sprachentwicklungsstörungen (SES), auch für den deutschsprachigen Raum.

Fragestellung

Ist eine solche Änderung in der Terminologie aus ärztlicher und psychologischer Sicht sinnvoll?

Material und Methode

Kritische Abwägung der Argumente für und gegen eine Nomenklaturänderung aus medizinischer und psychologischer Sicht eines Fachgesellschaften- und Leitliniengremiums.

Ergebnisse

Die ICD-10-GM (Internationale statistische Klassifikation der Krankheiten und verwandter Gesundheitsprobleme, 10. Revision, German Modification) und eine S2k-Leitlinie unterteilen SES in umschriebene SES (USES) und SES assoziiert mit anderen Erkrankungen (Komorbiditäten). Die USES- wie auch die künftige SES-Definition der ICD-11 (International Classification of Diseases 11th Revision) fordern den Ausschluss von Sinnesbehinderungen, neurologischen Erkrankungen und einer bedeutsamen intellektuellen Einschränkung. Diese Definition erscheint weit genug, um leichtere nonverbale Einschränkungen einzuschließen, birgt nicht die Gefahr, Kindern Sprach- und weitere Therapien vorzuenthalten und erkennt das ICD(International Classification of Disease)-Kriterium, nach dem der Sprachentwicklungsstand eines Kindes bedeutsam unter der Altersnorm und unterhalb des seinem Intelligenzalter angemessenen Niveaus liegen soll, an. Die intendierte Ersetzung des Komorbiditäten-Begriffs durch verursachende Faktoren, Risikofaktoren und Begleiterscheinungen könnte die Unterlassung einer dezidierten medizinischen Differenzialdiagnostik bedeuten.

Schlussfolgerungen

Die vorgeschlagene Terminologie birgt die Gefahr, ätiologisch bedeutsame Klassifikationen und differenzialdiagnostische Grenzen zu verwischen und auf wertvolles ärztliches und psychologisches Fachwissen in Diagnostik und Therapie sprachlicher Störungen im Kindesalter zu verzichten.

Cells of the human respiratory tract support the replication of pathogenic Old World orthohantavirus Puumala

BACKGROUND

Transmission of all known pathogenic orthohantaviruses (family Hantaviridae) usually occurs via inhalation of aerosols contaminated with viral particles derived from infected rodents and organ manifestation of infections is characterized by lung and kidney involvement. Orthohantaviruses found in Eurasia cause hemorrhagic fever with renal syndrome (HFRS) and New World orthohantaviruses cause hantavirus cardiopulmonary syndrome (HCPS). However, cases of infection with Old World orthohantaviruses with severe pulmonary manifestations have also been observed. Therefore, human airway cells may represent initial targets for orthohantavirus infection and may also play a role in the pathogenesis of infections with Eurasian orthohantaviruses.

METHODS

We analyzed the permissiveness of primary endothelial cells of the human pulmonary microvasculature and of primary human epithelial cells derived from bronchi, bronchioles and alveoli for Old World orthohantavirus Puumala virus (PUUV) in vitro. In addition, we examined the expression of orthohantaviral receptors in these cell types. To minimize donor-specific effects, cells from two different donors were tested for each cell type.

RESULTS

Productive infection with PUUV was observed for endothelial cells of the microvasculature and for the three tested epithelial cell types derived from different sites of the respiratory tract. Interestingly, infection and particle release were also detected in bronchial and bronchiolar epithelial cells although expression of the orthohantaviral receptor integrin β₃ was not detectable in these cell types. In addition, replication kinetics and viral release demonstrate enormous donor-specific variations.

CONCLUSIONS

The human respiratory epithelium is among the first targets of orthohantaviral infection and may contribute to virus replication, dissemination and pathogenesis of HFRS-causing orthohantaviruses. Differences in initial pulmonary infection due to donor-specific factors may play a role in the observed broad variance of severity and symptoms of orthohantavirus disease in patients. The absence of detectable levels of integrin α_Vβ₃ surface expression on bronchial and small airway epithelial cells indicates an alternate mode of orthohantaviral entry in these cells that is independent from integrin β₃.

Observations on early fungal infections with relevance for replant disease in fine roots of the rose rootstock Rosa corymbifera 'Laxa'

Replant disease is a worldwide phenomenon affecting various woody plant genera and species, especially within the Rosaceae. Compared to decades of intensive studies regarding replant disease of apple (ARD), the replant disease of roses (RRD) has hardly been investigated. The etiology of RRD is also still unclear and a remedy desperately needed. In greenhouse pot trials with seedlings of the RRD-sensitive rootstock Rosa corymbifera ‘Laxa’ cultured in replant disease affected soils from two different locations, early RRD symptom development was studied in fine roots. In microscopic analyses we found similarities to ARD symptoms with regards to structural damages, impairment in the root hair status, and necroses and blackening in the cortex tissue. Examinations of both whole mounts and thin sections of fine root segments revealed frequent conspicuous fungal infections in association with the cellular disorders. Particularly striking were fungal intracellular structures with pathogenic characteristics that are described for the first time. Isolated fungi from these tissue areas were identified by means of ITS primers, and many of them were members of the Nectriaceae. In a next step, 35 of these isolates were subjected to a multi-locus sequence analysis and the results revealed that several genera and species were involved in the development of RRD within a single rose plant. Inoculations with selected single isolates (Rugonectria rugulosa and Ilyonectria robusta) in a Perlite assay confirmed their pathogenic relationship to early necrotic host plant reactions, and symptoms were similar to those exhibited in ARD.

Rhizosphere microbial communities associated to rose replant disease: links to plant growth and root metabolites

Growth depression of Rosa plants at sites previously used to cultivate the same or closely related species is a typical symptom of rose replant disease (RRD). Currently, limited information is available on the causes and the etiology of RRD compared to apple replant disease (ARD). Thus, this study aimed at analyzing growth characteristics, root morphology, and root metabolites, as well as microbial communities in the rhizosphere of the susceptible rootstock Rosacorymbifera 'Laxa' grown in RRD-affected soil from two sites (Heidgraben and Sangerhausen), either untreated or disinfected by γ-irradiation. In a greenhouse bioassay, plants developed significantly more biomass in the γ-irradiated than in the untreated soils of both sites. Several plant metabolites detected in R. corymbifera 'Laxa' roots were site- and treatment-dependent. Although aloesin was recorded in significantly higher concentrations in untreated than in γ-irradiated soils from Heidgraben, the concentrations of phenylalanine were significantly lower in roots from untreated soil of both sites. Rhizosphere microbial communities of 8-week-old plants were studied by sequencing of 16S rRNA, ITS, and cox gene fragments amplified from total community DNA. Supported by microscopic observations, sequences affiliated to the bacterial genus Streptomyces and the fungal genus Nectria were identified as potential causal agents of RRD in the soils investigated. The relative abundance of oomycetes belonging to the genus Pythiogeton showed a negative correlation to the growth of the plants. Overall, the RRD symptoms, the effects of soil treatments on the composition of the rhizosphere microbial community revealed striking similarities to findings related to ARD.

The Hagfeldt Donor and Use of Next-Generation Bulky Donor Designs in Dye-Sensitized Solar Cells

"The Hagfeldt donor" is a bulky triarylamine building block with four alkyl chains in a 3-dimensional arrangement that is used with organic dyes in dye-sensitized solar cells (DSCs) in over 140 publications. Many of the highest performing DSC devices in literature make use of this group due to exceptional TiO₂ surface protection properties, which slows recombination of electrons in TiO₂ with the electrolyte. Importantly, record-setting cobalt and copper redox shuttle-based DSCs require exceptional surface protection to slow a facile recombination of electrons to these positively charged redox shuttles. Several syntheses have emerged for the Hagfeldt donor due to the need for iterative aryl-halide cross- coupling reactions complicating a straightforward route. Six synthetic strategies found in literature are described along with the challenges of each route. A recent method that has been put forward in the literature as a scalable, regioisomerically pure route is highlighted.

Incidence of dementia in the elderly: review of age and sex effects

A review of epidemiological studies about incidence of dementia among the aged is presented. Empirical studies on incidence of dementia have shown considerably differing estimations. Nevertheless, in all studies, an age-related increase in incidence becomes clearly apparent. Epidemiological field-studies could not yield consistent findings concerning the association of incidence and gender. However, most studies found an increased incidence for men until the age of 70–80 years. In older age most studies reported the same incidence for men and women or found an increased incidence of dementia in women. The findings are reviewed and discussed in the context of methodological issues.

Robust, Scalable Synthesis of the Bulky Hagfeldt Donor for Dye-Sensitized Solar Cells

The bulky triarylamine group commonly referred to as the "Hagfeldt donor" is a key building block found in many of the organic dyes used in dye-sensitized applications such as dye-sensitized solar cells (DSCs). This building block has gained popularity owing to its presence in many of the best-performing DSC devices reported to date, which use dyes containing this donor group. The Hagfeldt donor provides a desirable 3-dimensional structure that aids in surface protection of electrons injected into the semiconductor from oxidants in the electrolyte, allowing for record-setting cobalt- and copper-based redox shuttles to be utilized more frequently. However, the synthesis of this molecule has proven unreliable for many routes. This study concerns a novel, reliable and scalable five-step synthesis of the Hagfeldt donor.

Near-Infrared-Absorbing Indolizine-Porphyrin Push-Pull Dye for Dye-Sensitized Solar Cells

Porphyrins are attractive chromophores for application in dye-sensitized solar cells (DSCs), as judicious tuning of donor-acceptor properties can enable excellent near-infrared (NIR) absorption and exceptional device performance. Here, we report a porphyrin-based dye (SM85) conjugated to the planar strong electron donor, indolizine, designed to extend absorption further into the NIR region by inducing π-π interactions such as head-to-tail dye aggregation. The optoelectronic consequences of indolizine incorporation in SM85 include raising the ground-state oxidation potential and broadening and red-shifting ultraviolet-visible-NIR absorptions, along with increased molar absorptivity when compared to the dye SM315. Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations confirm the push-pull character of SM85, which features an overlap of frontier occupied and unoccupied orbitals. Steady-state spectrophotometric analyses reveal the presence of solution aggregates via absorption and emission spectroscopies. Aggregate modes were probed by DFT and TD-DFT analyses, and plausible models are presented. SM85-based DSC devices demonstrate a 5.7% power conversion efficiency (PCE) at full sun (7.4% PCE at 10% sun) with an exceptional improvement to the incident photon-to-current conversion onset at ∼850 nm. Current dynamics measurements, time-correlated single photon counting, and computational analyses are used to better understand device performances. This study puts forward a novel intramolecular charge-transfer porphyrin system with a dramatic shift into the NIR region, as is needed for nonprecious metal-based sensitizers, and provides an example of controlled, donor-acceptor-mediated aggregation as a complementary strategy to traditional donor-acceptor modifications to single-molecule π-systems in accessing enhancements in long wavelength light harvesting in molecular-based optoelectronic devices.

Analysis of the integrin β3 receptor for pathogenic orthohantaviruses in rodent host species

Host reservoir specificity of pathogens is complex and may depend on receptor variability. For pathogenic orthohantaviruses, integrin β₃ had been previously identified as entry receptor and the presence of aspartic acid residue at position 39 (D39) in human integrin β₃ was described to be a prerequisite for infection of primate cells with Hantaan virus (HTNV). However, the role of integrin β₃ in orthohantavirus infection of host animals is not completely understood. Therefore, we analyzed the nucleotide sequence of the integrin β₃ gene of Myodes glareolus and Apodemus agrarius, the hosts of Puumala virus (PUUV) and HTNV, respectively. Sequence analysis in tissue samples demonstrated that the amino acid residue D39 is not present in integrin β₃ of these natural orthohantavirus hosts. Furthermore, we analyzed the transcription and protein expression levels of integrin β₃ in the renal cell line BVK168 generated from the PUUV host, bank vole. Transcription level of integrin β₃ was 100-fold lower in BVK168 cells than in Vero E6 cells and integrin β₃ expression was not detectable in BVK168 cells. However, despite the absence of amino acid residue D39 and no detectable integrin β₃ expression, BVK168 cells are susceptible to infection with both PUUV and HTNV. These results indicate that the mechanism of orthohantaviral entry in rodent species does not correspond to the requirements that were described for the entry in primate cells in vitro.

Electronic decay of core-excited HCl molecules probed by THz streaking

The ultrafast electronic decay of HCl molecules in the time domain after resonant core excitation was measured. Here, a Cl-2p core electron was promoted to the antibonding σ^* orbital initiating molecular dissociation, and simultaneously, the electronic excitation relaxes via an Auger decay. For HCl, both processes compete on similar ultrashort femtosecond time scales. In order to measure the lifetime of the core hole excitation, we collinearly superimposed 40 fs soft x-ray pulses with intense terahertz (THz) radiation from the free-electron laser in Hamburg (FLASH). Electrons emitted from the molecules are accelerated (streaked) by the THz electric field where the resulting momentum change depends on the field's phase at the instant of ionization. Evaluation of a time-shift between the delay-dependent streaking spectra of photo- and Auger electrons yields a decay constant of (11 ± 2) fs for LMM Auger electrons. For further validation, the method was also applied to the MNN Auger decay of krypton. Reproduction of the value already published in the literature confirms that a temporal resolution much below the duration of the exciting x-ray pulses can be reached.

[Decision-making regarding treatment limitation after severe traumatic brain injury: A survey of French neurosurgeons]

BACKGROUND/INTRODUCTION

In France, the law defines and prohibits "unreasonable obstinacy" and provides a framework for the subsequent decision to limit or to cease treatment. It also gives the person the right to appoint a trusted person and to draft advance directives regarding this issue. There have been few studies of neurosurgeons' involvement in decision-making in regard to treatment limitation after severe traumatic brain injury.

AIM OF THE STUDY

The first aim of the study was to assess French neurosurgeons' adherence to the law on patients' rights and end of life which governs such decision-making. The second aim was to assess the prognostic and decision-making criteria applied by neurosurgeons.

METHODS

A declarative practice and opinion survey, using a self-administered questionnaire emailed to all practising neurosurgeons members of the French Society of Neurosurgery, was conducted from April to June 2016.

RESULTS

Of the 197 neurosurgeons contacted, 62 filled in the questionnaire. Discussions regarding treatment limitation were in all cases collegial, as required under the law, and the patient's neurosurgeon was always involved. The trusted person and/or family were always informed and consulted, but their opinions were not consistently taken into account. Advance directives were most often lacking (68%) [56; 80] or inappropriate (27%) [16; 38]. The most frequently used prognostic criteria were clinical parameters, intracranial pressure, cerebral perfusion pressure, and imaging, with significant interindividual variation in their use. The main decision-making criteria were foreseeable disability, expected future quality of life, and age.

CONCLUSIONS

Neurosurgeons showed good compliance with legal requirements, except in the matter of calling for the opinion of an external consultant. Furthermore, this survey confirmed variability in the use of prognosis predictors, and the need for further clinical research so as to achieve more-standardized practices to minimise the subjectivity in decision-making.

The role of oral anticoagulants in epistaxis

Purpose

The purpose of this retrospective study was to identify the impact of oral anticoagulants on epistaxis with the focus on new oral anticoagulants.

Methods

The study was conducted at the Department  for Ear- Nose- and Throat (ENT), Head and Neck Surgery, Technical University Munich, Germany. All patients presenting in 2014 with the diagnosis of epistaxis to a specialized ENT accident and emergency department were identified and analyzed in clinical data and medication.

Results

600 adult cases, with a median age of 66.6 years were identified with active bleeding. 66.8% of all cases were anticoagulated. Classic oral anticoagulants (COAC) were three times more common in patients than new-generation oral anticoagulants (NOAC). Recurrent bleeding was significantly associated with oral anticoagulants (OAC) (p = 0.014) and bleeding location was most often anterior (p = 0.006). In contrast, severe cases, which required surgery or embolization were significantly more likely in non-anticoagulated middle-aged patients with posterior bleedings (p < 0.05). In our epistaxis cohort, OAC were highly overrepresented (40%) when compared to the general German population (1%) but COAC as well as NOAC played only a minor role in severe courses of epistaxis.

Conclusion

Oral anticoagulation, especially with new-generation drugs, is not associated with more complicated and severe courses of epistaxis, but rather with recurrent bleeding. One should keep this information in mind when triaging the patient in the emergency room and when planning further procedures.

Real-life long-term effectiveness of fingolimod in Swiss patients with relapsing-remitting multiple sclerosis

Background and purpose

In 2011, fingolimod was approved in Switzerland for the treatment of relapsing‐remitting multiple sclerosis (RRMS). The aim of the present study was to assess the effectiveness and retention of fingolimod in a real‐life Swiss setting, in which patients can receive fingolimod as both first‐ and second‐line treatment for RRMS.

Methods

This cross‐sectional, observational study with retrospective data collection was performed at 19 sites that comprised both hospitals and office‐based physicians across Switzerland. Sites were asked to document eligible patients in consecutive chronological order to avoid selection bias. Demographic and clinical data from 274 consenting adult patients with RRMS who had received treatment with fingolimod were analyzed.

Results

Mean treatment duration with fingolimod was 32 months. Under fingolimod, 77.7% of patients remained free from relapses and 90.3% did not experience disability progression. The proportion of patients who were free from any clinical disease activity, i.e. without relapses and disability progression, was 72.1%. A total of 28.5% of patients had been RRMS treatment‐naïve prior to fingolimod therapy. High long‐term treatment retention rates ranging between 95.7% at 24 months and 87.8% at 36 months were observed.

Conclusion

In this Swiss cohort of naïve and pre‐treated subjects with RRMS, the majority of patients under fingolimod treatment showed freedom from relapses and disability progression. In addition, treatment retention rate over 2 and 3 years was high, irrespective of previous treatment.

Outcomes of Ulnar Shortening for Ulnar Impaction Syndrome Using the 2.7 mm AO Ulna Shortening Osteotomy System

Background: Ulnar shortening osteotomy is a well-established treatment for ulnar impaction syndrome. Controversy remains regarding the most effective system to achieve efficient bony union, whilst minimising incidence of complications, particularly hardware irritation. We present outcomes at 2 years using the recently released low profile AO osteotomy system.

Methods: 32 consecutive patients with significant pain from ulnar impaction syndrome (idiopathic or post-traumatic), without degenerative changes of the distal radio-ulnar joint, were included. Time to union, range of motion, grip strength, pain and complications were recorded.

Results: Median time to union was 10.14 weeks (9.27–11.01, 95%CI), with one nonunion. Visual Analogue Pain score, grip strength and range of motion improved significantly. No patient experienced hardware irritation. No plate required removal. Positive ulnar variance was reduced by 3.8 mm (mean).

Conclusions: The low profile AO system appears effective in achieving bony union whilst minimising incidence of hardware irritation, at a follow up of 2 years

Thermodynamic description of Tc(iv) solubility and carbonate complexation in alkaline NaHCO3–Na2CO3–NaCl systems

A comprehensive thermodynamic model is derived for the system Tc⁴⁺–Na⁺–Cl⁻–OH⁻–HCO₃⁻–CO₃²⁻–H₂O(l) based upon solubility experiments in alkaline carbonate solutions, advanced spectroscopic techniques and DFT calculations.

Iodine binding with thiophene and furan based dyes for DSCs

Donor–π-bridge–acceptor dyes with thiophene have been shown to bind I₂ leading to diminished dye-sensitized solar cell performances relative to furan based analogues.

International registry on the use of the CytoSorb® adsorber in ICU patients : Study protocol and preliminary results

INTRODUCTION

The aim of this clinical registry is to record the use of CytoSorb® adsorber device in critically ill patients under real-life conditions.

METHODS

The registry records all relevant information in the course of product use, e. g., diagnosis, comorbidities, course of the condition, treatment, concomitant medication, clinical laboratory parameters, and outcome (ClinicalTrials.gov Identifier: NCT02312024). Primary endpoint is in-hospital mortality as compared to the mortality predicted by the APACHE II and SAPS II score, respectively.

RESULTS

As of January 30, 2017, 130 centers from 22 countries were participating. Data available from the start of the registry on May 18, 2015 to November 24, 2016 (122 centers; 22 countries) were analyzed, of whom 20 centers from four countries provided data for a total of 198 patients (mean age 60.3 ± 15.1 years, 135 men [68.2%]). In all, 192 (97.0%) had 1 to 5 Cytosorb® adsorber applications. Sepsis was the most common indication for CytoSorb® treatment (135 patients). Mean APACHE II score in this group was 33.1 ± 8.4 [range 15-52] with a predicted risk of death of 78%, whereas the observed mortality was 65%. There were no significant decreases in the SOFA scores after treatment (17.2 ± 4.8 [3-24]). However interleukin-6 levels were markedly reduced after treatment (median 5000 pg/ml before and 289 pg/ml after treatment, respectively).

CONCLUSIONS

This third interim report demonstrates the feasibility of the registry with excellent data quality and completeness from 20 study centers. The results must be interpreted with caution, since the numbers are still small; however the disease severity is remarkably high and suggests that adsorber treatment might be used as an ultimate treatment in life-threatening situations. There were no device-associated side effects.

Deregulation of levels of angiopoietin-1 and angiopoietin-2 is associated with severe courses of hantavirus infection

BACKGROUND

Hantavirus disease is characterized by endothelial dysfunction. Angiopoietin-1 (Ang-1) and its antagonist angiopoietin-2 (Ang-2) play a key role in the control of capillary permeability. Ang-1 is responsible for maintenance of cell-to-cell contacts whereas Ang-2 destabilizes monolayers. An imbalance of Ang-1 and Ang-2 levels results in enhanced permeability and capillary leakage.

OBJECTIVES

To analyze the involvement of angiopoietins in hantavirus-induced disruption of endothelia, we measured the levels of Ang-1 and Ang-2 in hantavirus infection.

STUDY DESIGN

Levels of angiopoietins of 31 patients with acute Puumala virus (PUUV) infection and a patient infected with Dobrava-Belgrade virus genotype Sochi (DOBV-Sochi) were analyzed. An age-matched group of 16 healthy volunteers served as control. The ratios of Ang-2 to Ang-1 levels were calculated and correlated with laboratory parameters.

RESULTS

Patients with PUUV and DOBV-Sochi infection exhibited elevated ratios of Ang-2/Ang-1 compared to the control group. The imbalance of Ang-2 to Ang-1 levels was observed early after onset of symptoms and lasted for the acute phase of infection. The deregulation in DOBV-Sochi infection was more prominent than in PUUV infection. Analysis of Ang-2/Ang-1 ratio and laboratory parameters in the PUUV cohort revealed a positive correlation with serum creatinine and a negative correlation with serum albumin and thrombocyte levels.

CONCLUSIONS

We observed an imbalance between levels of Ang-1 and Ang-2 in patients infected with PUUV and DOBV-Sochi. Elevated Ang-2/Ang-1 ratios correlate with disease severity. The virus-induced deregulation of angiopoietin levels may enhance capillary permeability and contribute to the pathogenesis of hantavirus disease.

Functional disorders of swallowing

Swallowing involves complex coordination of the neuromuscular anatomy and physiology of the oropharynx and esophagus, controlled by the enteric and central nervous systems. Dysphagia is classified as either oropharyngeal or esophageal and results from mechanical or structural disturbances. Videofluoroscopy, fiberoptic endoscopic evaluation of swallowing, barium swallow, manometry, and endoscopy are common modalities utilized in diagnosis, but none is as important as a patient's history. Functional dysphagia is a diagnosis of exclusion and is based on Rome criteria. Its mechanism is unknown but potentially related to visceral hypersensitivity, inappropriate pain perception, or unidentified contraction abnormalities. Its management is mainly supportive; however, there is literature to suggest, but not confirm, benefit with the use of antidepressants. Continued understanding of functional dysphagia and other functional esophageal disorders, including globus sensation, will require further investigation into diagnostic algorithms and finding treatment methods.

Solubility and hydrolysis of Tc(iv) in dilute to concentrated KCl solutions: an extended thermodynamic model for Tc4+–H+–K+–Na+–Mg2+–Ca2+–OH−–Cl−–H2O(l) mixed systems

The solubility of Tc(iv) under strongly reducing conditions is investigated in KCl solutions with 1.5 ≤ pHm ≤ 14.5, and an extended thermodynamic model for the system Tc⁴⁺–H⁺–K⁺–Na⁺–Mg²⁺–Ca²⁺–OH⁻–Cl⁻–H₂O(l) is provided.

Clinical characterization of two severe cases of hemorrhagic fever with renal syndrome (HFRS) caused by hantaviruses Puumala and Dobrava-Belgrade genotype Sochi

BACKGROUND

Hantavirus disease belongs to the emerging infections. The clinical picture and severity of infections differ between hantavirus species and may even vary between hantavirus genotypes. The mechanisms that lead to the broad variance of severity in infected patients are not completely understood. Host- and virus-specific factors are considered.

CASE PRESENTATION

We analyzed severe cases of hantavirus disease in two young women. The first case was caused by Puumala virus (PUUV) infection in Germany; the second case describes the infection with Dobrava-Belgrade virus (DOBV) in Russia. Symptoms, laboratory parameters and cytokine levels were analyzed and compared between the two patients. Serological and sequence analysis revealed that PUUV was the infecting agent for the German patient and the infection of the Russian patient was caused by Dobrava-Belgrade virus genotype Sochi (DOBV-Sochi). The symptoms in the initial phase of the diseases did not differ noticeably between both patients. However, deterioration of laboratory parameter values was prolonged and stronger in DOBV-Sochi than in PUUV infection. Circulating endothelial progenitor cells (cEPCs), known to be responsible for endothelial repair, were mobilized in both infections. Striking differences were observed in the temporal course and level of cytokine upregulation. Levels of angiopoietin-2 (Ang-2), vascular endothelial growth factor (VEGF), and stromal derived factor-1 (SDF-1α) were increased in both infections; but, sustained and more pronounced elevation was observed in DOBV-Sochi infection.

CONCLUSIONS

Severe hantavirus disease caused by different hantavirus species did not differ in the general symptoms and clinical characteristics. However, we observed a prolonged clinical course and a late and enhanced mobilization of cytokines in DOBV-Sochi infection. The differences in cytokine deregulation may contribute to the observed variation in the clinical course.

Expression and characterization of a recombinant i-type lysozyme from the harlequin ladybird beetle Harmonia axyridis

Lysozymes are enzymes that destroy bacterial cell walls by hydrolysing the polysaccharide component of peptidoglycan. In insects, there are two classes of lysozymes, the c-type with muramidase activity and the i-type whose prototypical members from annelids and molluscs possess both muramidase and isopeptidase activities. Many insect genes encoding c-type and i-type lysozymes have been identified during genome and transcriptome analyses, but only c-type lysozymes have been functionally characterized at the protein level. Here we produced one of five i-type lysozymes represented in the immunity-related transcriptome of the invasive harlequin ladybird beetle Harmonia axyridis as recombinant protein. This was the only one containing the serine and histidine residues that are thought to be required for isopeptidase activity. This i-type lysozyme was recombinantly expressed in the yeast Pichia pastoris, but the purified protein was inactive in both muramidase and isopeptidase assays. Transcription and immunofluorescence analysis revealed that this i-type lysozyme is produced in the fat body but is not inducible by immune challenge. These data suggest that i-type lysozymes in insects may have acquired novel and as yet undetermined functions in the course of evolution.

Cerebral vasospasm after traumatic brain injury: an update

BACKGROUND

Post-traumatic vasospasm (PTV) remains a poorly understood entity. Using a systematic review approach, we examined the incidence, mechanisms, risk factors, impact on outcome and potential therapies of PTV.

METHODS

A search on Medline database up to 2015 performed with "traumatic brain injury" and "vasospasm" key-words retrieved 429 references. This systematic review was reported and analysed following the PRISMA criteria and according to the relevance in human clinical practice.

RESULTS

The research retrieved 429 references of which 226 were excluded from analysis because of their irrelevance and 87 finally included in the review.

CONCLUSION

Mechanical stretching, inflammation, calcium dysregulation, endotelin, contractile proteins, products of cerebral metabolism and cortical spreading depolarization have been involved in PTV pathophysiology. PTV occurs in up to 30-40% of the patients after severe traumatic brain injury. Usually, PTV starts within the first 3 days following head trauma and may last 5 to 10 days. Young age, low Glasgow Coma Score at admission and subarachnoid hemorrhage have been identified as risk factors of PTV. Suspected on transcranial Doppler, PTV diagnosis is best confirmed by angiography, CT angiography or MR angiography, and perfusion and ischaemic consequences by perfusion CT or MRI. Early PTV is associated with poor outcome. No PTV prevention strategy has proved efficient up to now. Regarding PTV treatment, only nimodipine and intra-arterial papaverine have been studied up to now. Treatment with milrinone has been described in a few cases reports and may represent a new therapeutic option.

Dynamic 1.5-T vs 3-T true fast imaging with steady-state precession (trueFISP)-MRI sequences for assessment of velopharyngeal function

OBJECTIVES

To compare the image quality of MRI scans produced with 1.5- and 3.0-T devices during functional test condition.

METHODS

65 MRI scans obtained with 1.5- (n = 43) or 3.0-T (n = 22) true fast imaging with steady-state precession (trueFISP) sequences from patients with a history of a cleft palate were evaluated. Two experts assessed the MRI scans, independently of each other, and blinded to the MRI technique used. Subjective ratings were entered on a five-point Likert scale. The median planes of three anatomical structures (velum, tongue and pharyngeal wall) were assessed in three functional states (at rest, during phonation of sustained "e" and during articulation of "kkk"). In addition, MRI scans taken during velopharyngeal closure were evaluated.

RESULTS

Under blinded conditions, both observers (radiologist and orthodontist) independently rated the quality of 1.5-T scans higher than that of 3.0 T. Statistical analysis of pooled data showed that the differences were highly significant (p < 0.009) in 4 out of 10 test conditions. The greatest differences in favour of 1.5 T were observed for MRI scans of the velum.

CONCLUSIONS

1.5 T used with trueFISP may be preferable over 3.0-T trueFISP for the evaluation of the velopharyngeal structures in the clinical routine.

Infectious disease outbreaks and increased complexity of care

AIM

This study examined the effects of healthcare-associated infectious disease outbreaks on nurses' work in a large acute care hospital in Ontario, Canada.

BACKGROUND

The incidence of healthcare-associated infections has increased. Previous research focuses on epidemiology, healthcare systems, and the economic burden of outbreaks. Few published studies focus on the impact of outbreaks on nurses' work in acute care facilities.

INTRODUCTION

Since the severe acute respiratory syndrome epidemic in 2003, combating infectious diseases has become a key issue. Hospitals have implemented measures related to healthcare-associated infections. However, nurses experience challenges in preventing, controlling, and contending with outbreaks.

METHODS

A retrospective exploratory case study approach was used. Data were collected over a 4-month period in 2012. The incidence rates of site-specific HAIs were analysed, and individual interviews were held with 23 bedside nurses and five nurse managers.

FINDINGS

Five themes emerged from the interviews: comparison of healthcare-associated infections outbreaks; the nature of nurses' work; impact of outbreaks on patient care; innovation and quality control in clinical practice; and increased and expanded IPAC measures. The incidence rates of methicillin-resistant Staphylococcus aureus, Clostridium difficile and vancomycin-resistant enterococci at the study site decreased, but remained above provincial benchmarks. Nurses experienced workload challenges, time pressures and psychological effects stemming from outbreaks and developed various innovations in response. Patient care was also affected.

CONCLUSION

Nurses' work has been impacted by healthcare-associated infectious disease outbreaks. Nursing workloads should be quantified to facilitate the development of guidelines for optimum nurse-patient ratio during outbreaks.

IMPLICATIONS FOR NURSING AND/OR HEALTH POLICY

A strong evidence-based policy framework is required to address healthcare-associated infectious disease outbreaks. Infection prevention and control guidelines and procedures should be established provincially and nationally. An interdisciplinary approach is essential for the creation of comprehensive and innovative strategies. Nursing research has increased understanding of the implications of infectious diseases in hospitals. Building on the literature, findings from this study can be used to influence policies on the care of patients who have secondary infections. Nurse-driven protocols are important and can lead to the creation of best practice guidelines that can be implemented across settings.

Cockroach GABAB receptor subtypes: molecular characterization, pharmacological properties and tissue distribution

γ-aminobutyric acid (GABA) is the predominant inhibitory neurotransmitter in the central nervous system (CNS). Its effects are mediated by either ionotropic GABAA receptors or metabotropic GABAB receptors. GABAB receptors regulate, via Gi/o G-proteins, ion channels, and adenylyl cyclases. In humans, GABAB receptor subtypes are involved in the etiology of neurologic and psychiatric disorders. In arthropods, however, these members of the G-protein-coupled receptor family are only inadequately characterized. Interestingly, physiological data have revealed important functions of GABAB receptors in the American cockroach, Periplaneta americana. We have cloned cDNAs coding for putative GABAB receptor subtypes 1 and 2 of P. americana (PeaGB1 and PeaGB2). When both receptor proteins are co-expressed in mammalian cells, activation of the receptor heteromer with GABA leads to a dose-dependent decrease in cAMP production. The pharmacological profile differs from that of mammalian and Drosophila GABAB receptors. Western blot analyses with polyclonal antibodies have revealed the expression of PeaGB1 and PeaGB2 in the CNS of the American cockroach. In addition to the widespread distribution in the brain, PeaGB1 is expressed in salivary glands and male accessory glands. Notably, PeaGB1-like immunoreactivity has been detected in the GABAergic salivary neuron 2, suggesting that GABAB receptors act as autoreceptors in this neuron.