Nonlinear statistical data assimilation for HVC $$_{\mathrm{RA}}$$ RA neurons in the avian song system

Abstract

With the goal of building a model of the HVC nucleus in the avian song system, we discuss in detail a model of HVC \(_{\mathrm{RA}}\) projection neurons comprised of a somatic compartment with fast Na \(^+\) and K \(^+\) currents and a dendritic compartment with slower Ca \(^{2+}\) dynamics. We show this model qualitatively exhibits many observed electrophysiological behaviors. We then show in numerical procedures how one can design and analyze feasible laboratory experiments that allow the estimation of all of the many parameters and unmeasured dynamical variables, given observations of the somatic voltage \(V_\mathrm{s}(t)\) alone. A key to this procedure is to initially estimate the slow dynamics associated with Ca, blocking the fast Na and K variations, and then with the Ca parameters fixed estimate the fast Na and K dynamics. This separation of time scales provides a numerically robust method for completing the full neuron model, and the efficacy of the method is tested by prediction when observations are complete. The simulation provides a framework for the slice preparation experiments and illustrates the use of data assimilation methods for the design of those experiments.

http://ift.tt/2dhO8GN

Esophageal stricture after endoscopic submucosal dissection treated successfully by temporary stent placement

Abstract

The growing use of endoscopic submucosal dissection (ESD) has enabled the highly curative treatment of early esophageal cancer. The circumferential extent of the tumor is reportedly related to the frequency of post-treatment stricture, with postoperative esophageal stricture reported to occur frequently when the post-resection mucosal defect exceeds 75 % of the esophageal luminal circumference. In some clinical cases, locally injected or orally administered steroids aimed at preventing post-treatment stricture fail to prevent re-stricture. Only two prior reports have investigated temporary stent placement for stricture after ESD for early esophageal cancer, and consensus is lacking on the appropriate duration and timing of stent placement. Here, we report our experience with a case of stricture after ESD for early esophageal cancer, in which temporary stent placement was effective for releasing the stricture for at least 6 months.

http://ift.tt/2cF0k6D

Quality of life and disability: can they be improved by active postoperative rehabilitation after spinal fusion surgery in patients with spondylolisthesis? A randomised controlled trial with 12-month follow-up

Abstract

Purpose

The aim of the study was to investigate the effectiveness of the postoperative 12-month exercise program compared to usual care on disability and health-related quality of life (HRQoL) in patients after lumbar spine fusion surgery (LSF).

Methods

Altogether, 98 patients with isthmic (31) or degenerative (67) spondylolisthesis were randomised to exercise therapy group (EG) (n = 48) or usual care group (UCG) (n = 50) 3 months after LSF. EG patients had home-based progressive strength and aerobic training program for 12 months. UCG patients received only oral and written instructions of exercises. Oswestry Disability Index (ODI) and HRQoL (RAND-36) were evaluated at the time of randomization, at the end of the intervention and 1 year after intervention.

Results

The mean ODI score decreased from 24 (12) to 18 (14) in the EG and from 18 (12) to 13 (11) in the UCG during intervention (between-groups p = 0.69). At 1-year follow-up, 25 % of the EG and 28 % of the UCG had an ODI score ≥20. No between-group differences in HRQoL change were found at any time point. The mean (95 % CI) physical functioning dimension of the HRQoL improved by 10.0 (4.6–15.3) in the EG and by 7.8 (2.5–13.0) in the UCG. In addition, the role physical score improved by 20.0 (7.7–32.3) in the EG and by 16.4 (4.4–28.4) in the UCG during the intervention.

Conclusions

The exercise intervention did not have an impact on disability or HRQoL beyond the improvement achieved by usual care. However, disability remained at least moderate in considerable proportion of patients.

http://ift.tt/2cFfqnH

Chirurgische Innovationen brauchen die Überprüfung in kontrollierten klinischen Studien

http://ift.tt/2dq9a42

Cacogenic Cartographies: Space and Place in the Eugenic Family Study

Abstract

Though only one component product of the larger eugenics movement, the eugenic family study proved to be, by far, its most potent ideological tool. The Kallikak Family, for instance, went through eight editions between 1913 and 1931. This essay argues that the current scholarship has missed important ways that the architects of the eugenic family studies theorized and described the subjects of their investigation. Using one sparsely interrogated work (sociologist Frank Wilson Blackmar's "The Smoky Pilgrims") and one previously unknown eugenic family study (biologist Frank Gary Brooks' untitled analysis of the flood-zone Oklahomans) from the Southern Plains, this essay aims to introduce "environment" as a schema that allows for how the subjects of the eugenic family study were conceptualized with respect to their surroundings. Geospatially and environmentally relevant constructions of scientific knowledge were central to the project of eugenics during its formative years, but remain largely and conspicuously absent from the critical literature which engages this project to separate the fit from the unfit in American society. The dysgenic constituted a unique human geography, giving us significant insight into how concatenations of jurisprudence as well as cultural and social worth were tied to the land.

http://ift.tt/2dhFl7K

Association between a functional variant in RAD51 gene’s 3′ untranslated region and its mRNA expression in lymphoblastoid cell lines

Variants of microRNA (miRNA)-binding sites in RAD51 gene's 3′ untranslated region (3′UTR) are significantly associated with cancer risk, but the roles of these genetic variants in post-transcriptional regulation ...

http://ift.tt/2deBXde

Genome characterization of two NADC30-like porcine reproductive and respiratory syndrome viruses in China

The recent emergence of NADC30-like porcine reproductive and respiratory syndrome virus (PRRSV) in vaccinated pigs arose more attentions for the high incidents of mutation and recombination of PRRSVs.

http://ift.tt/2dI3arl

Efficacy of low dose capecitabine and sorafenib in patients with advanced alfa-fetoprotein secreting hepatocellular carcinoma: a 1 year experience

There is no global consensus for the optimal management of HCC. Most of patients at the time of diagnosis are not candidate for potentially curative therapy. The study aimed to evaluate the efficacy of low dos...

http://ift.tt/2deB2tt

Crayfish bury their own exuviae: a newly discovered behavioral pattern in decapods

Invertebrates are a very diverse group of animals, showing a wide spectrum of life strategies and adaptations. They often exhibit very complex behavioural and social patterns. In crayfish, the largest freshwat...

http://ift.tt/2dI3dUr

Impact of headaches on university students in Durban, South Africa

Introspection into the factors that affect student success at higher education institutions has gained significant momentum in recent years. Teaching and learning has come under the spotlight with quality enha...

http://ift.tt/2deBbgA

Erratum to: Perceptions and Preferences of Two Etanercept Autoinjectors for Rheumatoid Arthritis: A New European Union-Approved Etanercept Biosimilar (Benepali ® ) Versus Etanercept (Enbrel ® ) - Findings from a Nurse Survey in Europe

http://ift.tt/2dxZ3Po

Selective debarking by ungulates in temperate deciduous forests: preference towards tree species and stem girth

Abstract

Debarking by ungulates has various effects on stem development and forest tree composition. Selectivity for debarking may prevail based on tree species and stem girth. We investigated this selective utilization based on species and size composition of available and debarked stems. Measurements were taken on 2100 sampling points in different temperate deciduous forests of Mátra Mountains region, Hungary. We distinguished specific stem injuries from each other. Factors influencing debarking (stem density and diversity, understory browsing) were also studied. Frequency of debarking was very low (5 % of sampling points). It was the lowest in beech forests (0.2 %) and the highest in Turkey oak–sessile oak forests (6 %). The proportion of injured stems varied between 0.001 % in beech forests to 0.04 % in Turkey oak–sessile oak forests. Ash, linden and maple trees were the most utilized; ash was revealed as significantly preferred species. Most of the injured stems had a perimeter between 12 and 21 cm, proved as preferred stem size interval. Trunks larger than 50 cm girth were generally avoided. Bark stripping and antler rubbing occurred mainly on thinner ash stems, whereas bark rubbing on larger oak stems. Understory density and diversity was significantly higher at debarked sampling points than intact ones. Ungulate debarking is functioning as selective natural disturbance. As a driver of forest vegetation dynamics, its total elimination should not be targeted from forest ecosystems. We recommend maintaining a diverse forest composition to ensure selective stem utilization of ungulates and reduce damage on major tree species of economic importance.

http://ift.tt/2ddKInN

Temporal Regularity Detection and Rate Discrimination in Cochlear-Implant Listeners

Abstract

Cochlear implants (CIs) convey fundamental-frequency information using primarily temporal cues. However, temporal pitch perception in CI users is weak and, when measured using rate discrimination tasks, deteriorates markedly as the rate increases beyond 300 pulses-per-second. Rate pitch may be weak because the electrical stimulation of the surviving neural population of the implant recipient may not allow accurate coding of inter-pulse time intervals. If so, this phenomenon should prevent listeners from detecting when a pulse train is physically temporally jittered. Performance in a jitter detection task was compared to that in a rate-pitch discrimination task. Stimuli were delivered using direct stimulation in cochlear implants, on a mid-array and an apical electrode, and at two different rates (100 and 300 pps). Average performance on both tasks was worse at the higher pulse rate and did not depend on electrode. However, there was a large variability across and within listeners that did not correlate between the two tasks, suggesting that rate-pitch judgement and regularity detection are to some extent limited by task-specific processes. Simulations with filtered pulse trains presented to NH listeners yielded broadly similar results, except that, for the rate discrimination task, the difference between performance with 100- and 300-pps base rates was smaller than observed for CI users.

http://ift.tt/2de75cO

Influence of Numerical Cementation on Multiphase Displacement in Rough Fractures

Abstract

We present an application of 3D X-ray computed microtomography for studying the influence of numerical cementation on flow in a cement-lined rough-walled fracture. The imaged fracture geometry serves as input for flow modeling using a combination of the level set and the lattice Boltzmann methods to characterize the capillary-dominated fluid displacement properties and the relative permeability of the naturally cemented fracture. We further numerically add cement to the naturally cement-lined fracture to quantify the effect of increasing cement thickness and diminishing aperture on flow properties. Pore space geometric tortuosity and capillary pressure as a function of water saturation both increase with the numerically increased fracture cement thickness. The creation of unevenly distributed apertures and cement contact points during numerical cement growth causes the wetting and non-wetting fluids to impede each other, with no consistent trends in relative permeability with increasing saturation. Tortuosity of wetting and non-wetting fluid phases exhibits none to poor correlation with relative permeability and thus cannot be used to predict it, contrary to previous findings in smoother fractures.

http://ift.tt/2dpq6Yi

Free Surface Flow in a Microfluidic Corner and in an Unconfined Aquifer with Accretion: The Signorini and Saint-Venant Analytical Techniques Revisited

Abstract

Steady, laminar, fully developed flows of a Newtonian fluid driven by a constant pressure gradient in (1) a curvilinear constant cross section triangle bounded by two straight no-slip segments and a circular meniscus and (2) a wedge bounded by two rays and an adjacent film bulging near the corner are studied analytically by the theory of holomorphic functions and numerically by finite elements. The analytical solution of the first problem is obtained by reducing the Poisson equation for the longitudinal flow velocity to the Laplace equation, conformal mapping of the corresponding transformed physical domain onto an auxiliary half-plane and solving there the Signorini mixed boundary value problem (BVP). The numerical solution is obtained by meshing the circular sector and solving a system of linear equations ensuing from the Poisson equation. Comparisons are made with known solutions for flows in a rectangular conduit, circular annulus and Philip's circular duct with a no-shear sector. Problem (2) is treated by the Saint-Venant semi-inverse method: the free surface (quasi-meniscus) is reconstructed by a one-parametric family, which specifies a holomorphic function of the first derivative of the physical coordinate with respect to an auxiliary variable. The latter maps the flow domain onto a quarter of a unit disc where a mixed BVP for a characteristic function is solved by the Zhukovsky–Chaplygin method. Velocity distributions in a cross section perpendicular to the flow direction are obtained. It is shown that the change of the type of the boundary condition from no slip to perfect slip (along the meniscus) causes a dramatic increase of the total flow rate (conductance). For example, the classical Saint-Venant formulae for a sector, with all three boundaries being no-slip segments, predict up to four times smaller rate as compared to a free surface meniscus. Mathematically equivalent problems of unconfined flows in aquifers recharged by a constant-intensity infiltration are also addressed.

http://ift.tt/2dp9wYI

Limiting overdiagnosis of low-risk prostate cancer through an evaluation of the predictive value of transrectal and power Doppler ultrasonography

Abstract

Purpose

Overdiagnosis induced by prostate cancer screening makes necessary a better selection of candidate patients for prostate biopsy. The objective of our study is to assess the probability of having a high- or low-risk lesion that could require active surveillance (AS) after biopsies and a normal or abnormal examination, including transrectal and power Doppler ultrasonography (TRUS-PDS).

Methods

Four hundred and twenty-nine consecutive patients with a PSA level <10 ng/ml and a normal digital rectal examination (DRE) had guided biopsies in a prospective study. We used D'Amico's criteria to assess the risk of a biological recurrence and Dall'Era's criteria to assess possible AS. The TRUS-PDS was considered positive if one biopsy was positive in the same sextant as the suspect image.

Results

One hundred and seventy-seven out of 429 (41 %) T1c cancers were diagnosed; 131 out of 177 (74 %) could be qualified as low risk, and 119 out of 177 (67 %) could require AS. The TRUS-PDS was normal in 285 of 429 patients (66 %). With a normal TRUS-PDS, the probability of not having cancer with a high or intermediate risk was 96 % (negative predictive value). With an abnormal TRUS-PDS, the probability of having a positive biopsy was 59 %, and the probability of having a significant cancer was 30 %, according to the Dall'Era criteria. When TRUS-PDS was normal, these probabilities significantly decreased to 32 and 5 %, respectively (p < 0.01).

Conclusions

Patients with a PSA level <10 ng/ml, a normal DRE, and a normal TRUS-PDS have a less than 5 % risk of high- or intermediate-risk cancer.

http://ift.tt/2de6Z4Y

Clinical spectrum and diagnostic pitfalls of multiple abnormal uptakes on bone scintigraphy

Abstract

Bone scintigraphy with technetium-99m (^99mTc)-labeled diphosphonates is one of the most frequently performed radionuclide procedures. Accumulation of ^99mTc-labeled diphosphonate is well recognized to reflect conditions of accelerated bone turnover and metabolism. Therefore, it is a functional imaging modality for detecting metastatic bone tumors, metabolic bone disease, traumatic injury, and inflammation. This pictorial essay describes the possible patterns of distribution of abnormal uptake for differential diagnosis of metastatic bone tumor, as well as the diagnostic pitfalls of bone scintigraphy.

http://ift.tt/2cEFv6l

Umbilical Cord-Derived Mesenchymal Stem Cell Transplantation in Hepatitis B Virus Related Acute-on-Chronic Liver Failure Treated with Plasma Exchange and Entecavir: a 24-Month Prospective Study

Abstract

Background & Aim

Search for an effective therapy for patients with hepatitis B virus related acute-on-chronic liver failure (HBV-ACLF) remains an important issue. This study investigated the efficacy of umbilical cord-derived mesenchymal stem cell (UC-MSC) transplantation in patients with HBV-ACLF.

Methods

45 consecutive entecavir-treated HBV-ACLF patients were prospectively studied. Among these patients, 11 received both plasma exchange (PE) and a single transplantation of UC-MSCs (group A), while 34 received only PE (group B). The primary endpoint was survival at 24 months.

Results

Compared with group B, levels of albumin, alanine aminotransferase, aspartate aminotransferase, total bilirubin, direct bilirubin, prothrombin time (PT), international normalized ratio (INR) and model for end-stage liver disease score in group A improved significantly at 4 weeks after transplantation (p < 0.05). Levels of albumin, PT and INR in group A were also markedly improved at 24 months (p < 0.05). Group A had significantly higher cumulative survival rate at 24 months (54.5 % v.s. 26.5 %, p = 0.015 by log rank test). Between the two groups, levels of creatinine, White blood cell, hemoglobin and platelet were similar. HBeAg loss and hepatocellular carcinoma incidence were similar at 24 months. Group assignment (relative risk: 2.926, 95%confidence interval: 1.043–8.203, p = 0.041) was an independent predictor for survival at 24 months. Success rate of UC-MSC transplantation was 100 % in group A. No severe adverse event was observed in any patient.

Conclusion

UC-MSC transplantation is safe and effective for HBV-ACLF patients treated with PE and entecavir. It further improves the hepatic function and survival.

http://ift.tt/2duAJOS

Incidence of infusion reactions to anti-neoplastic agents in early phase clinical trials: The MD Anderson Cancer Center experience

Abstract

Infusion reactions (IRs) to anti-neoplastic agents require prompt recognition and immediate treatment to avert significant complications. We conducted a retrospective review of the medical records of consecutive patients who received anti-neoplastic therapy in the outpatient treatment center of the Department of Investigational Cancer Therapeutics from January 1, 2013 to November 30, 2013. Of the 597 patients who received treatment, 9 (1.5 %) had IRs (all ≤ grade 2). The most common IRs observed on first occurrence were chills (n = 5), itching, rash, and facial flushing (n = 3 each). There were no IR-related deaths. All the IRs were reversible with appropriate symptomatic treatment and the therapy was completed after temporary cessation of infusion in 7 of the 9 patients. The infusion was stopped in 2 patients due to symptoms suggestive of IgE-mediated allergic reaction and cytokine storm. Five of the 8 patients who were re-challenged with the same therapy developed a similar reaction. However, the infusion was completed in 4 of the 5 patients after administration of intravenous diphenhydramine and/or hydrocortisone, or slowing the rate of infusion. And, subsequent cycles with the same agents were uneventful. IRs to anti-neoplastic agents are rare. Though the clinical presentations are overlapping, most IRs are not IgE-mediated allergic reactions. Appropriate premedication and slow rate of infusion facilitates uneventful administration of the anti-neoplastic agents in subsequent cycles. Further study in a larger cohort of patients to identify biomarkers of hypersensitivity is warranted.

http://ift.tt/2cO4wPX

Risk factors for recurrent injurious falls that require hospitalization for older adults with dementia: a population based study

Abstract

Background

Older adults with dementia are at an increased risk of falls, however, little is known about risk factors for recurrent injurious falls (a subsequent fall after the first fall has occurred) among this group. This study aimed to identify risk factors for recurrent injurious falls requiring hospitalization among adults aged 60+ years with dementia.

Methods

This retrospective, whole-population cohort study was conducted using the Western Australian Hospital Morbidity Data System and Western Australian Death Registrations from 2001 to 2013. Survival analysis using a stratified conditional Cox model (type 1) was undertaken to identify risk factors for recurrent injurious falls requiring hospitalization.

Results

There were 32,519 participants with an index hospital admission with dementia during the study period. Over 27 % (n = 8970) of the cohort experienced a total of 11,073 injurious falls requiring hospitalization during follow up with 7297 individuals experiencing a single fall, 1330 experiencing two falls and 343 experiencing three or more falls. The median follow-up time for each individual was 2.49 years. Females were at a significantly increased risk of 7 % for recurrent injurious falls resulting in hospitalization (adjusted hazard ratio 1.07, 95 % CI 1.01–1.12), compared to males. Increasing age, living in rural areas, and having an injurious fall in the year prior to the index hospital admission with dementia also increased the risk of recurrent injurious falls resulting in hospitalization.

Conclusions

Screening those with dementia for injurious falls history could help to identify those most at risk of recurrent injurious falls. Improvement of heath care and falls prevention services for those with dementia who live in rural areas may also reduce recurrent injurious falls.

http://ift.tt/2dxADWu

Persistency, medication prescribing patterns, and medical resource use associated with multiple sclerosis patients receiving oral disease-modifying therapies: a retrospective medical record review

Abstract

Background

In the US, the approved multiple sclerosis (MS) oral disease-modifying therapies (ODMTs) are fingolimod (FTY), teriflunomide (TFN), and dimethyl fumarate (DMF). FTY and TFN are recommended with once-daily doses with no up-titration, whereas DMF treatment is recommended twice-daily (BID) and is initiated with a 7-day starter dose of 120 mg BID before up-titration to the maintenance dose of 240 mg BID. Limited information exists regarding real-world ODMT prescribing patterns to aid physician/patient decision-making.

Methods

Eligible patients for this retrospective medical record review were ≥18 years, had one visit related to ODMT initiation (index visit), and ≥1 visit within 12 months before and after the index visit. Primary objectives were to assess post-index ODMT persistency (i.e., discontinuation), prescribing patterns (medication switching, dose up-titrations, dose reduction, re-starts, and add-ons) and medical resource utilization (office-visits, MRI procedures, and mobility indicators) at distinct time windows of 3, 6, 9, and 12 months. Chi-square or Wilcoxon Rank Sum tests were used for 3-way ODMT group comparisons.

Results

Medical records of 293 MS-diagnosed patients using ODMTs were abstracted from 19 US-based neurology clinics between December 31, 2010 and June 30, 2014 (FTY: 101; DMF: 133; TFN: 59). Persistency rates among ODMT groups were similar. MS-related medication switching, dose reduction, re-starts, and add-ons were infrequently observed and were similar across ODMT groups. Of DMF patients with a confirmed starting dose of 120 mg BID with ≥12 months follow-up (n = 26), the percentage who were prescribed dose up-titrations to the recommended maintenance DMF dose was 23.1 % at 1–3 months, 26.9 % at 4–6 months, 42.3 % at 7–9 months, and 0 % at 10–12 months. There were no significant differences at any time window among the ODMT groups in the number of office visits or percent of patients receiving MRIs. Mobility indicator patterns (proportion of patients with abnormal gait, wheelchair use, etc.) were consistent over time.

Conclusions

There was no difference in persistency, prescribing patterns (medication switching, dose reduction, re-starts, and add-ons) or medical resource utilization (office-visits, MRI procedures, and mobility indicators) among the ODMTs. However, in a small sub-group of patients, delays of up to 9 months in DMF dose-up titration to the recommended maintenance dose were observed.

http://ift.tt/2d8SsIG

Efficacy and safety of pharmacological treatments for Lyme neuroborreliosis in children: a systematic review

Abstract

Background

Many aspects of pharmacological treatment of Lyme neuroborreliosis in children, such as choice of drug, dosage, and duration are subject to intense debates, leading to uncertainties in patients' parents and healthcare providers alike. To assess the available evidence for pharmacological treatment for children with Lyme neuroborreliosis we conducted a systematic review.

Methods

The comprehensive systematic literature search included randomized-controlled trials (RCTs) and non-randomized studies (NRS) on treatment of Lyme neuroborreliosis in children (age <18 years). Our primary outcome was neurological symptoms after treatment. Risk of bias was assessed with the Cochrane risk of bias tools for RCTs and NRS. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

Results

Two RCTs and four NRS were eligible for inclusion. Risk of bias in RCTs and NRS was generally high. Reporting of studies was generally poor. Regarding the primary outcome neurological symptoms at 1–3 months, no statistically significant difference could be found in cohort studies between doxycycline and beta-lactam antibiotics. In two RCTs comparing penicillin G and ceftriaxone, no patient experienced residual neurological symptoms at the last reported time points. Quality of evidence according to GRADE was judged very low.

Conclusions

Data is scarce and with limited quality. Several issues could not be addressed due to scarcity of information. No eligible study compared different treatment durations. According to the available evidence, there seems to be no difference between different antibiotic agents for the treatment of Lyme neuroborreliosis in children regarding neurological symptoms. We found no evidence that supports extended antibiotic regimes.

Review registration

Systematic review registration: CRD42014008839.

http://ift.tt/2dxA0Mr

Hes1: the maestro in neurogenesis

Abstract

The process of neurogenesis is well orchestrated by the harmony of multiple cues in a spatiotemporal manner. In this review, we focus on how a dynamic gene, Hes1, is involved in neurogenesis with the view of its regulation and functional implications. Initially, we have reviewed the immense functional significance drawn by this maestro during neural development in a context-dependent manner. How this indispensable role of Hes1 in conferring the competency for neural differentiation partly relies on the direct/indirect mode of repression mediated by very specific structural and functional arms of this protein has also been outlined here. We also review the detailed molecular mechanisms behind the well-tuned oscillatory versus sustained expression of this antineurogenic bHLH repressor, which indeed makes it a master gene to implement the elusive task of neural progenitor propensity. Apart from the functional aspects of Hes1, we also discuss the molecular insights into the endogenous regulatory machinery that regulates its expression. Though Hes1 is a classical target of the Notch signaling pathway, we discuss here its differential expression at the molecular, cellular, and/or regional level. Moreover, we describe how its expression is fine-tuned by all possible ways of gene regulation such as epigenetic, transcriptional, post-transcriptional, post-translational, and environmental factors during vertebrate neurogenesis.

http://ift.tt/2cOjl4M

Cadmium acetate as a ring opening polymerization catalyst for the polymerization of rac -lactide, ε -caprolactone and as a precatalyst for the polymerization of ethylene

Abstract

In the present study, we have discussed the bulk ring opening polymerization (ROP) of rac-lactide (rac-LA) and ε-caprolactone (ε-CL) using Cd(OAc)₂. Cd(OAc)₂ appeared to be a good catalyst for the polymerization of rac-LA and ε-CL yielding high molecular weight (M _n) polymers with narrow molecular weight distributions (MWDs). The catalytic activity of the system can be increased markedly upon using catalytic amount of BnOH as external alcoholic initiator. There is a first order dependence of the rate constant with respect to monomer concentrations as understood from the kinetic studies. The rate was found to be faster in the presence of BnOH. The polymerization process was controlled. The polymerization proceeded via the coordination-insertion mechanism without BnOH as well as activated monomer mechanism in the presence of BnOH. In the absence of BnOH, the acetyl group initiated the polymerization as understood from the ¹H NMR and MALDI-TOF analysis. The benzyloxy group initiated the polymerization in the presence of BnOH. Moderate activity towards the polymerization of ethylene was observed using MAO as alkyl aluminum activator. The polymerization parameters towards the polymerization of ethylene were widely investigated.

Graphical abstract

The catalytic activity of Cd(OAc)₂ towards the ROP of rac-LA and ε-CL and precatalyst for the polymerization of ethylene were investigated.

http://ift.tt/2dpdkcx

Der Nightmare Effects Questionnaire (NEQ)

Zusammenfassung

Hintergrund

Alpträume kommen auch im Jugend- und Erwachsenenalter vor und können zum Teil massive Auswirkungen auf das Tagesbefinden der Betroffenen haben. Die wenigen Fragebögen zur Erfassung der Auswirkungen von Alpträumen erheben oft nur einen Teilbereich der möglichen Beeinträchtigungen und berücksichtigen nur das Erwachsenenalter.

Fragestellung

Der Nightmare Effects Questionnaire (NEQ) wurde entwickelt, um die Lücke an fehlenden umfassenden Messinstrumenten zur Erfassung von Alptraumauswirkungen auf das Tagesbefinden von Jugendlichen und Erwachsenen zu schließen.

Material und Methoden

Der NEQ ist in zwei Abschnitte unterteilt. Der erste Abschnitt erfasst anhand von sechs Fragen die Häufigkeit verschiedener Traumarten. Im zweiten Abschnitt wird durch 35 Items die Tagesbeeinträchtigung durch Alpträume erfasst. 382 Teilnehmer (14–24 Jahre) füllten den NEQ vollständig aus, und mit den Daten von 73 Probanden mit regelmäßigen Alpträumen wurden die psychometrischen Daten des NEQ geprüft.

Ergebnisse

Mithilfe einer Hauptkomponentenanalyse wurde die Faktorenstruktur des NEQ geprüft. Es ergaben sich folgende sechs Faktoren: 1) Emotionsregulation, 2) Stress und Aggressivität, 3) Depression, 4) Aufmerksamkeit/Konzentration, 5) Angst, 6) Hyperaktivität. Die Reliabilität der Gesamtskala lag im sehr guten Bereich mit α = 0,929.

Diskussion

Der NEQ weist eine hohe Reliabilität auf und kann damit als ein gut einsetzbares Instrument zu Erfassung der Tagesbeeinträchtigungen durch Albträume bei Jugendlichen und Erwachsenen angesehen werden. Er ist somit gut in Forschung und Praxis einsetzbar.

http://ift.tt/2ddYJBZ

MITK-OpenIGTLink for combining open-source toolkits in real-time computer-assisted interventions

Abstract

Purpose

Due to rapid developments in the research areas of medical imaging, medical image processing and robotics, computer-assisted interventions (CAI) are becoming an integral part of modern patient care. From a software engineering point of view, these systems are highly complex and research can benefit greatly from reusing software components. This is supported by a number of open-source toolkits for medical imaging and CAI such as the medical imaging interaction toolkit (MITK), the public software library for ultrasound imaging research (PLUS) and 3D Slicer. An independent inter-toolkit communication such as the open image-guided therapy link (OpenIGTLink) can be used to combine the advantages of these toolkits and enable an easier realization of a clinical CAI workflow.

Methods

MITK-OpenIGTLink is presented as a network interface within MITK that allows easy to use, asynchronous two-way messaging between MITK and clinical devices or other toolkits. Performance and interoperability tests with MITK-OpenIGTLink were carried out considering the whole CAI workflow from data acquisition over processing to visualization.

Results

We present how MITK-OpenIGTLink can be applied in different usage scenarios. In performance tests, tracking data were transmitted with a frame rate of up to 1000 Hz and a latency of 2.81 ms. Transmission of images with typical ultrasound (US) and greyscale high-definition (HD) resolutions of \(640\times 480\) and \(1920\times 1080\) is possible at up to 512 and 128 Hz, respectively.

Conclusion

With the integration of OpenIGTLink into MITK, this protocol is now supported by all established open-source toolkits in the field. This eases interoperability between MITK and toolkits such as PLUS or 3D Slicer and facilitates cross-toolkit research collaborations. MITK and its submodule MITK-OpenIGTLink are provided open source under a BSD-style licence (http://mitk.org).

http://ift.tt/2duATkU

Staphylococcus capitis isolated from prosthetic joint infections

Abstract

Further knowledge about the clinical and microbiological characteristics of prosthetic joint infections (PJIs) caused by different coagulase-negative staphylococci (CoNS) may facilitate interpretation of microbiological findings and improve treatment algorithms. Staphylococcus capitis is a CoNS with documented potential for both human disease and nosocomial spread. As data on orthopaedic infections are scarce, our aim was to describe the clinical and microbiological characteristics of PJIs caused by S. capitis. This retrospective cohort study included three centres and 21 patients with significant growth of S. capitis during revision surgery for PJI between 2005 and 2014. Clinical data were extracted and further microbiological characterisation of the S. capitis isolates was performed. Multidrug-resistant (≥3 antibiotic groups) S. capitis was detected in 28.6 % of isolates, methicillin resistance in 38.1 % and fluoroquinolone resistance in 14.3 %; no isolates were rifampin-resistant. Heterogeneous glycopeptide-intermediate resistance was detected in 38.1 %. Biofilm-forming ability was common. All episodes were either early post-interventional or chronic, and there were no haematogenous infections. Ten patients experienced monomicrobial infections. Among patients available for evaluation, 86 % of chronic infections and 70 % of early post-interventional infections achieved clinical cure; 90 % of monomicrobial infections remained infection-free. Genetic fingerprinting with repetitive sequence-based polymerase chain reaction (rep-PCR; DiversiLab®) displayed clustering of isolates, suggesting that nosocomial spread might be present. Staphylococcus capitis has the potential to cause PJIs, with infection most likely being contracted during surgery or in the early postoperative period. As S. capitis might be an emerging nosocomial pathogen, surveillance of the prevalence of PJIs caused by S. capitis could be recommended.

http://ift.tt/2dxvcH3

Potential clinical and economic outcomes of active beta-D-glucan surveillance with preemptive therapy for invasive candidiasis at intensive care units: a decision model analysis

Abstract

Early initiation of antifungal treatment for invasive candidiasis is associated with change in mortality. Beta-D-glucan (BDG) is a fungal cell wall component and a serum diagnostic biomarker of fungal infection. Clinical findings suggested an association between reduced invasive candidiasis incidence in intensive care units (ICUs) and BDG-guided preemptive antifungal therapy. We evaluated the potential cost-effectiveness of active BDG surveillance with preemptive antifungal therapy in patients admitted to adult ICUs from the perspective of Hong Kong healthcare providers. A Markov model was designed to simulate the outcomes of active BDG surveillance with preemptive therapy (surveillance group) and no surveillance (standard care group). Candidiasis-associated outcome measures included mortality rate, quality-adjusted life year (QALY) loss, and direct medical cost. Model inputs were derived from the literature. Sensitivity analyses were conducted to evaluate the robustness of model results. In base-case analysis, the surveillance group was more costly (1387 USD versus 664 USD) (1 USD = 7.8 HKD), with lower candidiasis-associated mortality rate (0.653 versus 1.426 per 100 ICU admissions) and QALY loss (0.116 versus 0.254) than the standard care group. The incremental cost per QALY saved by the surveillance group was 5239 USD/QALY. One-way sensitivity analyses found base-case results to be robust to variations of all model inputs. In probabilistic sensitivity analysis, the surveillance group was cost-effective in 50 % and 100 % of 10,000 Monte Carlo simulations at willingness-to-pay (WTP) thresholds of 7200 USD/QALY and ≥27,800 USD/QALY, respectively. Active BDG surveillance with preemptive therapy appears to be highly cost-effective to reduce the candidiasis-associated mortality rate and save QALYs in the ICU setting.

http://ift.tt/2d8PjIW

Local Health Study

Zusammenfassung

Hintergrund

Der unzureichende Zugang zur Prävention und medizinischen Versorgung von Sexarbeiterinnen (SW) stellt eine Herausforderung für das deutsche Gesundheitssystem dar. Die Erreichbarkeit und die Versorgung der SW in Bochum durch eine Zusammenarbeit zwischen der Interdisziplinären Immunologischen Ambulanz, Zentrum für Sexuelle Gesundheit und Medizin des St. Josef-Hospitals (ZSG), dem Gesundheitsamt Bochum und Madonna e. V. zu verbessern stand im Fokus dieser Arbeit.

Patienten und Methodik

Es wurde ein aufsuchendes medizinisches Angebot zur Diagnostik von sexuell übertragbaren Infektionen (STI) bei SW im Bochumer Bordellbereich zwischen August 2013 und Januar 2014 bereitgestellt. Nach Aufklärung und mündlichem Einverständnis der SW wurden pseudonymisierte, kostenlose HIV-, Syphilis-, Chlamydien-, Gonorrhö- und Trichomonadentests angeboten und durchgeführt.

Ergebnisse

Es wurden 112 SW erreicht (zu 55,4 % im Rahmen der STI-Outreach-Studie), 94,6 % der SW wiesen einen Migrationshintergrund auf. Die Mehrzahl der SW war zwischen 20 und 29 Jahre alt (61,3 %). Im Kollektiv waren lediglich 19,0 % krankenversichert. Folgende STI wurden diagnostiziert: 12,5 % Chlamydien, 6,2 % Syphilis, 3,6 % Gonorrhö, 3,6 % Trichomonaden und 0,9 % HIV. Weiterhin erfolgte eine Gegenüberstellung dieser Ergebnisse mit STI-Untersuchungen bei SW in Deutschland. Die Behandlung erfolgte nach den Standards der Deutschen STI-Gesellschaft.

Schlussfolgerungen

Das Angebot verbesserte in Bochum die Erreichbarkeit und die Inanspruchnahme des medizinischen Angebots durch SW. Eine weitere Verbesserung dieses Angebotes ist dringend notwendig.

http://ift.tt/2dainmF

Stereotactic body radiotherapy in non-operable lung cancer patients

http://ift.tt/2cYR6hz

Emotion Ideology Mediates Effects of Risk Factors on Alexithymia Development

Abstract

Despite its connection to mental and behavioral health complications, elevated alexithymia tends to be associated with low responsiveness and high resistance to psychological intervention. To further understanding of potential treatment targets for clients with alexithymic traits, the present study explored the (a) independent contributions of various risk factors to statistical predictions of alexithymic trait severity, (b) generalizability of risk factor contributions across two culturally distinct samples, and (c) potential for emotion ideology (i.e., beliefs about emotion and emotional experience) to mediate such contributions. Preliminary results suggest emotion socialization and child abuse may be salient contributors to alexithymia severity, whereas effects of trauma exposure may be limited to samples with high overall exposure to alexithymia risk-factors. Moreover, emotion ideology mediates the relation between risk-factor exposure and alexithymia severity. Thus, psychotherapeutic interventions targeting emotion ideology may be beneficial when working with clients with elevated alexithymia.

http://ift.tt/2dnFsQQ

Delayed gadolinium-enhanced MRI of meniscus (dGEMRIM) and cartilage (dGEMRIC) in healthy knees and in knees with different stages of meniscus pathology

Abstract

Background

Lesions in the meniscus are risk factors for developing knee osteoarthritis (OA), not least because of the role of the meniscus in the pathological progression of OA. Delayed gadolinium enhanced MRI of cartilage (dGEMRIC) has extensively been used to identify pre-radiographic cartilage changes in OA. In contrast, its counterpart with regard to examination of the meniscus, gadolinium enhanced MRI of meniscus (dGEMRIM), has been less utilized. In this study we use 3D dGEMRIM in patients with meniscus lesions and compare them with previous results of healthy individuals.

Methods

Eighteen subjects with MRI-verified posteromedial meniscus lesions and 12 healthy subjects with non-injured and non-symptomatic knee joints, together 30 volunteers, were examined using 3D Look-Locker sequence after intravenous injection of Gd-DTPA²⁻ (0.2 mmol/kg body weight). Relaxation time (T1) was measured in the posterior meniscus and femoral cartilage before and 60, 90, 120 and 180 min after injection. Relaxation rate (R1 = 1/T1) and change in relaxation rate (ΔR1) were calculated. For statistical analyses, Student's t-test and Analysis of Variance (ANOVA) were used.

Results

The pre-contrast diagnostic MRI identified two sub-cohorts in the 18 patients with regard to meniscus injury: 1) 11 subjects with MRI verified pathological intrameniscal changes (grade 2) in the posteromedial meniscus only and no obvious cartilage changes. The lateral meniscus showed no pathology. 2) 7 subjects with MRI verified pathological rupture (grade 3) of the posteromedial meniscus and pathological changes in the lateral meniscus and/or medial and lateral joint cartilage.

Comparisons of pathological and healthy posteromedial meniscus revealed opposite patterns in both T1_Gd and ΔR1 values between pathological meniscus grade 2 and grade 3. The concentration of the contrast agent was lower than in healthy meniscus in grade 2 lesions (p = 0.046) but tended to increase in grade 3 lesions (p = 0.110). Maximum concentration of contrast agent was reached after 180 min in both cartilage and menisci (except for grade 3 menisci where the maximum concentration was reached after 90 min).

Conclusion

dGEMRIM and dGEMRIC may be feasible to combine in vivo, preferably with one examination before and one 2 h after contrast injection. Possible different dGEMRIM patterns at different stages of meniscus lesions must be taken into account when evaluating meniscus pathology.

http://ift.tt/2dCJcLV

Diagnostic utility of a computer-aided diagnosis system for whole-body bone scintigraphy to detect bone metastasis in breast cancer patients

Abstract

Objective

To compare the diagnostic ability of planar images (PI) and images obtained by a computer-aided diagnosis (CAD) system (Viewer for Standardized Bone Scintigraphies; VSBONE) of whole-body bone scintigraphy for detecting bone metastases in breast cancer patients.

Methods

81 women (median: 56 years; range: 32–79) with a history of breast cancer were included in this study. They underwent whole-body bone scintigraphy after intravenous injection of 740 MBq technetium-99m hydroxymethylene diphosphonate. A total of 1066 bones (162 regions of the skull, 657 regions of the spine and pelvis, 223 regions of the sternum and rib, 18 regions of the upper extremities, and 6 regions of the lower extremities) were analyzed. The PI alone, VSBONE images alone, and both PI and VSBONE images (PI + VSBONE) were interpreted independently by two radiologists to diagnose bone metastases, which were then confirmed by magnetic resonance imaging. The sensitivity and specificity for each modality were analyzed using Fisher's exact and McNemar tests. Inter-reviewer agreement was evaluated using a kappa statistic.

Results

Bone metastases were confirmed in 43 patients with 442 positive lesions. The average sensitivity of PI, VSBONE images, and PI + VSBONE images was 40.8, 50.2, and 61.8 %, respectively. The average specificity was 97.8, 97.5, and 97.6 %, respectively. The kappa scores were 0.62 for PI, 0.69 for VSBONE, and 0.77 for PI + VSBONE.

Conclusions

VSBONE was superior to PI in regard to sensitivity for detecting bone metastases in breast cancer patients. However, an improved CAD system is required to decrease the number of false-negative results.

http://ift.tt/2cEpoFR

Incidence of infusion reactions to anti-neoplastic agents in early phase clinical trials: The MD Anderson Cancer Center experience

Abstract

Infusion reactions (IRs) to anti-neoplastic agents require prompt recognition and immediate treatment to avert significant complications. We conducted a retrospective review of the medical records of consecutive patients who received anti-neoplastic therapy in the outpatient treatment center of the Department of Investigational Cancer Therapeutics from January 1, 2013 to November 30, 2013. Of the 597 patients who received treatment, 9 (1.5 %) had IRs (all ≤ grade 2). The most common IRs observed on first occurrence were chills (n = 5), itching, rash, and facial flushing (n = 3 each). There were no IR-related deaths. All the IRs were reversible with appropriate symptomatic treatment and the therapy was completed after temporary cessation of infusion in 7 of the 9 patients. The infusion was stopped in 2 patients due to symptoms suggestive of IgE-mediated allergic reaction and cytokine storm. Five of the 8 patients who were re-challenged with the same therapy developed a similar reaction. However, the infusion was completed in 4 of the 5 patients after administration of intravenous diphenhydramine and/or hydrocortisone, or slowing the rate of infusion. And, subsequent cycles with the same agents were uneventful. IRs to anti-neoplastic agents are rare. Though the clinical presentations are overlapping, most IRs are not IgE-mediated allergic reactions. Appropriate premedication and slow rate of infusion facilitates uneventful administration of the anti-neoplastic agents in subsequent cycles. Further study in a larger cohort of patients to identify biomarkers of hypersensitivity is warranted.

http://ift.tt/2cO4wPX

First genetic characterisation of Giardia in human isolates from Jordan

Abstract

Little is known about the epidemiology of Giardia in Jordan and to date, no genotyping studies have been conducted on Giardia isolates from Jordanians. In the present study, a total of 49 microscopy-positive faecal samples from Jordanian patients suffering from giardiasis were analysed at two loci: the triose phosphate isomerase (tpi) gene and the glutamate dehydrogenase (gdh) gene. At the tpi locus, a total of 28 samples amplified and assemblage A was identified in 46.4 % (13/28) samples, while assemblage B was identified in 50 % (14/28) samples and a mixed assemblage A and B was identified in one sample (3.6 %) (Table 1). At the gdh locus 48 isolates amplified and of these assemblages A was identified in 43.7 % (21/48) of isolates and assemblage B in 56.3 % (27/48) of isolates. No mixed infections were detected at the gdh locus. Subtyping at the gdh locus identified sub-assemblage AII in 43.7 % (21/48) of isolates and sub-assemblages BIII and BIV in 25 % (12/48) and 31.2 % (15/48) of isolates, respectively, with more genetic diversity in AII isolates than BIII or BIV isolates. Novel sub-types within each sub-assemblage were identified suggesting unique endemicity and anthroponotic transmission of Giardia in Jordanian patients suffering from giardiasis. Further studies are required to better understand the epidemiology and transmission of Giardia in Jordan.

http://ift.tt/2dH0hr1

Aelurostrongylus abstrusus in wild felids of South Africa

Abstract

The increasing interest on respiratory nematodes of domestic cats (Felis silvestris catus) has recently stimulated several studies on their epidemiology and geographic distribution. At the same time, there are still important gaps in our knowledge of the infections caused by respiratory nematodes in wild felids. The present study investigated the occurrence of pulmonary parasites in wild hosts housed in sanctuaries and protected areas of South Africa. Faecal samples collected from seven species of wild felids living in three study sites were copromicroscopically and genetically examined. Of twenty-one samples six, i.e. three from caracals (Caracal caracal), two from lions (Panthera leo) and one from a serval (Leptailurus serval), scored positive for the metastrongyloid Aelurostrongylus abstrusus at copromicroscopic and/or molecular tests. No other lungworms were recorded. The occurrence of the cosmopolitan cat lungworm A. abstrusus in wild hosts has been so far questioned. Importantly, the present findings represent an unequivocal evidence of the capability of A. abstrusus to infect some species of wild felids. Further studies are warranted to understand the epidemiological patterns of lungworms in wild and domestic felids, and to better investigate the impact of these parasitoses on health and welfare of wild animals.

http://ift.tt/2ddFCZ4

Echinococcus multilocularis (Cestoda, Cyclophyllidea, Taeniidae): oncospheral hook morphogenesis

Abstract

Ultrastructural characteristics of the oncospheral hook morphogenesis in the taeniid cestode Echinococcus multilocularis Leuckart, 1863, a parasite of medical and veterinary importance, are described. Oncospheral hook primordia appear at the preoncospheral phase of the embryonic development. Within six specialised cells of the so-called oncoblasts, high concentration of mitochondria, numerous ribosomes and extended Golgi regions are involved in hook development. During hook growth, the blade and base gradually protrude outside the oncoblast plasma membrane. The nucleated oncoblast persists around the handles of fully formed hooks. Simultaneously with the hook primordium elongation and transformation into a blade, handle and base, the hook material differentiates into an electron-dense cortex and a less dense inner core. The exit of the blade of each mature hook, protruding from the oncosphere, is surrounded by a circular, septate desmosome and two rigid, dense rings on either side. The pattern of oncospheral hook morphogenesis in E. multilocularis is compared with that of other previously examined cyclophyllidean cestodes. Though oncoblasts have never been observed around the mature hooks, their remnants are often still visible in the fully developed infective oncospheres in particular in some taeniid species so far examined in this respect. The origin and formation of oncospheral hooks in E. multilocularis, evidently differs from that of the rostellar hooks. Thus, although the hooks may have slight similarity at the gross level, they are neither analogous nor homologous structures.

http://ift.tt/2dH0Xwp

Analysis of the virulence determination mechanisms in a local Toxoplasma strain (T.gHB1) isolated from central China

Abstract

Several rhoptry proteins (ROPs) have been confirmed to be critical virulence factors of Toxoplasma gondii strains from North America and Europe. The two active kinases ROP17 and ROP18, and pseudokinase ROP5 were thought to be the key determinants of parasites' virulence in laboratory mice. Given the genetic diversity of Toxoplasma strains from different geographical regions, the virulence determinants in other strains, particularly the ones that are phylogenetically distant to the North American and European strains, are yet to be elucidated. In this study, we sought to examine the contribution of three known virulence factors to the virulence of a type I strain (T.gHB1) isolated from Central China. We deleted ROP17 and ROP18 individually, as well as in combination with GRA7 by the CRISPR-Cas9 system in this local isolate. Subsequent virulence tests in mice indicated that deletion of GRA7, ROP17, or ROP18 in T.gHB1showed similar attenuation in mice as the type I RH strain lacking the corresponding proteins. However, in contrast to the reported double knockouts in RH, double deletions of GRA7 plus ROP17 or GRA7 plus ROP18 in T.gHB1 did not show significant further virulence attenuation compared to the ROP17 or ROP18 single knockouts. These results indicated that GRA7, ROP18 and ROP17 may play different roles in virulence determination in genetically diverse strains of Toxoplasma.

http://ift.tt/2ddIx3A

Ectoparasites of bats (Mammalia: Chiroptera) in Atlantic forest fragments in north-eastern Brazil

Abstract

In Brazil, most studies involving parasites of bats (bat flies) treat the mid-west, south-east, and south of the country. This work aimed to characterize the ectoparasites community associated with bats in the Atlantic forest in the state of Sergipe, north-eastern Brazil. Sampling was conducted between January and June 2013 in the Serra de Itabaiana National Park (PNSI) and between November 2013 and June 2015 in the Wildlife Refuge Mata do Junco (RVSMJ). Parasitological indexes were determined, and the influence of host sex and the seasonality in prevalence rates and mean intensity for the most abundant parasites was evaluated. Some 129 parasites were collected in PNSI and 296 in RVSMJ, and 100 and 70.6 %, respectively, belong to the family Streblidae. The differences in parasitological rates in Sergipe in relation to other studies may be associated with the environmental characteristics and the composition of the host community. The influence of sex and the seasonal prevalence of Speiseria ambigua and Trichobius joblingi, associated with Carollia perspicillata, may be associated with a lower rate of female captures and low sampling in the dry season. This is a pioneer study in Sergipe that reveals the occurrence of 16 species of streblids and representatives of Acari and Basilia spp., highlighting the need for more studies to increase the wealth and understanding of host-parasite associations in the state.

http://ift.tt/2dH0udQ

Molecular survey of arthropod-borne pathogens in sheep keds ( Melophagus ovinus ), Central Europe

Abstract

In the study, we screened a total of 399 adult sheep keds (Melophagus ovinus) for the presence of RNA and DNA specific for arboviral, bacterial, and protozoan vector-borne pathogens. All investigated keds were negative for flaviviruses, phleboviruses, bunyaviruses, Borrelia burgdorferi, Rickettsia spp., Anaplasma phagocytophilum, "Candidatus Neoehrlichia mikurensis," and Babesia spp. All ked pools were positive for Bartonella DNA. The sequencing of the amplified fragments of the gltA and 16S-23S rRNA demonstrated a 100 % homology with Bartonella melophagi previously isolated from a sheep ked and from human blood in the USA. The identification of B. melophagi in sheep keds in Central Europe highlights needs extending a list of hematophagous arthropods beyond ticks and mosquitoes for a search of emerging arthropod-borne pathogens.

http://ift.tt/2ddFGrA

Histological location of myxosporean plasmodia in fish tissue with Luna’s method

Abstract

In the present study, a staining technique, Luna's method, has been used for detection and tissue location of myxosporean spores/plasmodia in histological sections of gills and liver. The Luna's staining was performed on the sections of the tissue fixed in Bouin's, embedded in paraffin wax. The mature plasmodia were stained in bright red color and pansporoblasts and gill tissue stained in blue. This staining helped to detect and locate even a single myxospore of less than 15 μm in size located within the tissues of the host.

http://ift.tt/2dH1kHq

Impact of experimental flooding on larvae and pupae of dung-breeding Culicoides

Abstract

Culicoides biting midges (Diptera: Ceratopogonidae) spend the greatest part of their life in the larval stage. However, knowledge on the immature stages and the impact of abiotic factors on their development is still poor. Therefore, we investigated the effect of flooding on the larvae and pupae of Culicoides chiopterus (Meigen, 1830) and C. dewulfi Goetghebuer, 1936. In water, the larvae of both species showed head-to-tail flexions and sinuous flexions, at slow rates, but were not able to swim. Flooding of larvae for 24 h did not affect the number of emerging adults; flooding of pupae significantly reduced the emergence rate of C. chiopterus, compared to the control group, while C. dewulfi was not affected. Pupae were not able to float and no pupae survived flooding for 10 days. After flooding of larvae for 10 days, 50 % of C. chiopterus and 4 % of C. dewulfi completed the pre-adult development. During this treatment, 84 % of C. chiopterus and 48 % of C. dewulfi larvae pupated in water.

http://ift.tt/2ddGflm

Ecological study on antimicrobial-resistant zoonotic bacteria transmitted by flies in cattle farms

Abstract

Flies were qualitatively and quantitatively monitored on both livestock animals and the surrounding environment to investigate their role as a potential carrier for antimicrobial-resistant bacteria of zoonotic importance in cattle farms. This was done by the use of visual observations and animal photography; meanwhile, in the surrounding environment, flies were collected using sticky cards and then microscopically identified. Representative fly samples were cultured for bacterial isolation, biochemical identification, and then tested against common 12 antibiotics. The total average of dipterous flies in examined farms was 400.42 ± 6.2. Culicoides biting midges were the most common existing species (70.01 %) followed by house flies, stable flies, and mosquitoes (18.31, 7.74, and 3.91 %, respectively) at X ² = 9.0, P < 0.05. The most predominant bacterial isolates were Escherichia coli (22.6 %), Staphylococcus aureus and Enterobacter (17.3 % each), coagulase-negative Staphylococci (CNS) (14.7 %), Klebsiella sp. (8 %), Salmonella spp. (6.7 %), and Shigella spp. and Proteus spp. (6.7 % each). The tested bacterial isolates were resistant to variant antibiotics used. S. aureus exhibited 100 % resistance to colistine. However, E. coli revealed 92.9 and 78.6 % resistance against tetracycline and colistine, respectively. Both Salmonella spp. and Shigella spp. were 100 % resistant to penicillin, and Klebsiella sp. had 100 % resistance to tetracycline. In conclusion, Culicoides biting midges and house flies could be considered as a potential carrier for multi-drug-resistant bacteria of zoonotic importance. Furthermore, cows' environment has an essential role in propagation and wide spread of antimicrobial-resistant bacterial pathogens.

http://ift.tt/2dGZHJE

A novel PCR-RFLP assay for molecular characterization of Echinococcus granulosus sensu lato and closely related species in developing countries

Abstract

Cystic echinococcosis, due to Echinococcus granulosus sensu lato (s. l.), currently affects three million people, especially in low-income countries and results in high livestock production loss. DNA-based methods demonstrated genetic variability of E. granulosus s. l., and five species were recognized to belong to the complex, including E. granulosus sensu stricto (s.s) (genotypes G1–G3), Echinococcus equinus (genotype G4), Echinococcus ortleppi (genotype G5), Echinococcus canadensis (genotypes G6–G10), and the lion strain Echinococcus felidis. The characterization of Echinococcus species responsible for human and animal echinococcosis is crucial to adapt the preventive measures against this parasitic disease. The sequencing approach is the gold standard for genotyping assays. Unfortunately, developing countries do not often have access to these techniques. Based on in silico RFLP tools, we described an accurate PCR-RFLP method for Echinococcus spp. characterization. The double digestion with the HaeIII and HinfI restriction enzymes of the PCR product from nad1 gene (1071 bp) led to a clear discrimination between E. granulosus s. l. and most closely related species (Echinococcus shiquicus and Echinococcus multilocularis).

Molecular procedures and phylogenetic analysis confirmed the efficiency and the reproducibility of this simple and fast PCR-RFLP method. This technique is proved useful for fresh/unfixed and FF-PET tissues and enables large-scale molecular epidemiological screening in developing countries.

http://ift.tt/2ddGwog

Origin of host-parasite associations of Marsupialges misonnei (Acariformes: Psoroptidae)—a parasitological detective story

Abstract

Host associations of permanent ectoparasitic mite Marsupialges misonnei Fain, 1963 (Acariformes: Psoroptidae: Marsupialginae) are analyzed. This species was first recorded from an ethanol-preserved museum specimen of Caluromys philander (Linnaeus, 1758) (Didelphimorphia: Didelphidae) originating from French Guiana. We discovered specimens of M. misonnei from both species known in the carnivore genus Nasua (Carnivora: Procyonidae): N. narica (Linnaeus, 1766) from Panama (collected in the field) and N. nasua (Linnaeus, 1766) from Brazil (collected from dry museum specimen). Two alternative hypotheses about an initial host of this mite (bare-tailed woody opossum or coatis) are discussed. We argue that M. misonnei was originally parasitic on Nasua spp. and occasionally contaminated C. philander from these hosts in the collecting process.

http://ift.tt/2dH0IS0

Unveiling the oxidative metabolism of Rhipicephalus microplus (Acari: Ixodidae) experimentally exposed to entomopathogenic fungi

Abstract

Rhipicephalus microplus is an important tick in tropical regions due to the high economic losses caused by its parasitism. Metarhizium anisopliae and Beauveria bassiana are well-known entomopathogenic fungi that can afflict R. microplus ticks. The development of new targets and strategies to control this parasite can be driven by studies of this tick's physiology. Recently, it was reported that when exposed to adverse physiological conditions, ticks can activate fermentative pathways, indicating transition from aerobic to anaerobic metabolism. Nevertheless, the precise mechanism by which entomopathogenic fungi influence R. microplus metabolism has not been clarified, limiting understanding of the tick-fungus association. Thus, the present study aimed to evaluate the effect of infection of ticks by M. anisopliae and B. bassiana on the amount of selected carboxylic acids present in the hemolymph, enabling increased understanding of changes previously reported. The results showed preservation in the concentrations of oxalic, lactic, and pyruvic acids in the hemolymph 24 and 48 h after dropping from cattle; while there were variations in the concentration of these carboxylic acids after infection of female ticks to M. anisopliae and B. bassiana. Significant increases were observed in the concentration of oxalic and lactic acids and significant reduction of pyruvic acid for both observation times (24 and 48 h) after infection by entomopathogenic fungi. These results indicate that B. bassiana and M. anisopliae infection alters the basal metabolism of R. microplus females, resulting in the activation of fermentative pathways.

http://ift.tt/2ddGpsE

Comparative diagnostic accuracy of hepatocyte-specific gadoxetic acid (Gd-EOB-DTPA) enhanced MR imaging and contrast enhanced CT for the detection of liver metastases: a systematic review and meta-analysis

Abstract

Purpose

This systematic review evaluated the diagnostic accuracy and impact on patient management of hepatocyte-specific gadoxetic acid enhanced magnetic resonance imaging (GA-MRI) compared to contrast enhanced computed tomography (CE-CT) in patients with liver metastases.

Method

Four biomedical databases (PubMed, EMBASE, Cochrane Library, York CRD) were searched from January 1991 to February 2016. Studies investigating the accuracy or management impact of GA-MRI compared to CE-CT in patients with known or suspected liver metastases were included. Bias was evaluated using QUADAS-II. Univariate meta-analysis of sensitivity ratios (RR) were conducted in the absence of heterogeneity, calculated using I ² , Tau values (τ) and prediction intervals.

Results

Nine diagnostic accuracy studies (537 patients with 1216 lesions) and four change in management studies (488 patients with 281 lesions) were included. Per-lesion sensitivity and specificity estimates for GA-MRI ranged from 86.9–100.0 % and 80.2–98.0 %, respectively, compared to 51.8–84.6 % and 77.2–98.0 % for CE-CT. Meta-analysis found GA-MRI to be significantly more sensitive than CE-CT (RR = 1.29, 95 % CI = 1.18–1.40, P < 0.001), with equivalent specificity (RR = 0.97, 95 % CI 0.910–1.042, P = 0.44). The largest difference was observed for lesions smaller than 10 mm for which GA-MRI was significantly more sensitive (RR = 2.21, 95 % CI = 1.47–3.32, P < 0.001) but less specific (RR = 0.92, 95 % CI 0.87–0.98, P = 0.008). GA-MRI affected clinical management in 26 of 155 patients (16.8 %) who had a prior CE-CT; however, no studies investigated the consequences of using GA-MRI instead of CE-CT.

Conclusion

GA-MRI is significantly more sensitive than CE-CT for detecting liver metastases, which leads to a modest impact on patient management in the context of an equivocal CE-CT result.

http://ift.tt/2du7WW3

Language identification of multilingual posts from Twitter: a case study

Abstract

This paper describes a method for handling multi-class and multi-label classification problems based on the support vector machine formalism. This method has been applied to the language identification problem in Twitter. The system evaluation was performed mainly on a Twitter data set developed in the TweetLID workshop. This data set contains bilingual tweets written in the most commonly used Iberian languages (i.e., Spanish, Portuguese, Catalan, Basque, and Galician) as well as the English language. We address the following problems: (1) social media texts. We propose a suitable tokenization that processes the peculiarities of Twitter; (2) multilingual tweets. Since a tweet can belong to more than one language, we need to use a multi-class and multi-label classifier; (3) similar languages. We study the main confusions among similar languages; and (4) unbalanced classes. We propose threshold-based strategy to favor classes with less data. We have also studied the use of Wikipedia and the addition of new tweets in order to increase the training data set. Additionally, we have tested our system on Bergsma corpus, a collection of tweets in nine languages, focusing on confusable languages using the Cyrillic, Arabic, and Devanagari alphabets. To our knowledge, we obtained the best results published on the TweetLID data set and results that are in line with the best results published on Bergsma data set.

http://ift.tt/2cE6Zct

Role of lasers as an adjunct to scaling and root planing in patients with type 2 diabetes mellitus: a systematic review

Abstract

The aim of the study was to assess the efficacy of adjunctive use of laser therapy (LT) alone or antimicrobial photodynamic therapy (aPDT) to improve clinical periodontal and HbA1c levels in patients with both chronic periodontitis (CP) and type 2 diabetes mellitus (T2DM). Electronic search of the MEDLINE, PubMed, EMBASE, Science Direct, and SCOPUS databases were combined with hand searching of articles published from 1975 up to and including March 2016 using relevant MeSH terms. Six studies were selected for this review. In these six studies, laser treatment was applied, after scaling and root planing (SRP), in two ways: Three studies used laser alone and three studies used laser with photosensitizer. All the six included studies reporting clinical periodontal and glycemic parameters showed that LT and aPDT were effective in the treatment of CP in T2DM subjects at follow-up. Two studies showed significantly better periodontal outcomes for LT as an adjunct to SRP as compared to SRP alone, whereas four studies showed comparable periodontal outcomes among adjunctive LT or aPDT with SRP. Two studies showed significant reduction of HbA1c levels in LT and aPDT as compared to SRP, whereas three studies showed comparable percentage levels at follow-up. It remains debatable whether LT or aPDT as adjunct to SRP is more effective as compared to SRP alone in the improvement of clinical periodontal and glycemic control in patients with both CP and T2DM, given that the scientific evidence is weak.

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Body fluid levels of neuroactive amino acids in autism spectrum disorders: a review of the literature

Abstract

A review of studies on the body fluid levels of neuroactive amino acids, including glutamate, glutamine, taurine, gamma-aminobutyric acid (GABA), glycine, tryptophan, d-serine, and others, in autism spectrum disorders (ASD) is given. The results reported in the literature are generally inconclusive and contradictory, but there has been considerable variation among the previous studies in terms of factors such as age, gender, number of subjects, intelligence quotient, and psychoactive medication being taken. Future studies should include simultaneous analyses of a large number of amino acids [including d-serine and branched-chain amino acids (BCAAs)] and standardization of the factors mentioned above. It may also be appropriate to use saliva sampling to detect amino acids in ASD patients in the future—this is noninvasive testing that can be done easily more frequently than other sampling, thus providing more dynamic monitoring.

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