Atomistic Picture of Fluorescent Probes with Hydrocarbon Tails in Lipid Bilayer Membranes: An Investigation of Selective Affinities and Fluorescent Anisotropies in Different Environmental Phases.

By reverting to spectroscopy, changes in the biological environment of a fluorescent probe can be monitored and the presence of various phases of the surrounding lipid bilayer membranes can be detected. However, it is currently not always clear in which phase the probe resides. The well-known orange 1,1'-dioctadecyl-3,3,3',3'-tetramethylindodicarbo-cyanine perchlorate (DiI-C18(5)) fluorophore, for instance, and the new, blue BODIPY (4,4-difluoro-4-bora-3 a,4 a-diaza- s-indacene) derivative were experimentally seen to target and highlight identical parts of giant unilamellar vesicles of various compositions, comprising mixtures of dipalmitoylphosphatidylcholine (DPPC), dioleoylphosphatidylcholine (DOPC), sphingomyelin (SM), and cholesterol (Chol). However, it was not clear which of the coexisting membrane phases were visualized (Bacalum et al., Langmuir. 2016, 32, 3495). The present study addresses this issue by utilizing large-scale molecular dynamics simulations and the z-constraint method, which allows evaluating Gibbs free-energy profiles. The current calculations give an indication why, at room temperature, both BODIPY and DiI-C18(5) probes prefer the gel (So) phase in DOPC/DPPC (2:3 molar ratio) and the liquid-ordered (Lo) phase in DOPC/SM/Chol (1:2:1 molar ratio) mixtures. This study highlights the important differences in orientation and location and therefore in efficiency between the probes when they are used in fluorescence microscopy to screen various lipid bilayer membrane phases. Dependent on the lipid composition, the angle between the transition-state dipole moments of both probes and the normal to the membrane is found to deviate clearly from 90°. It is seen that the DiI-C18(5) probe is located in the headgroup region of the SM/Chol mixture, in close contact with water molecules. A fluorescence anisotropy study also indicates that DiI-C18(5) gives rise to a distinctive behavior in the SM/Chol membrane compared to the other considered membranes. The latter behavior has not been seen for the studied BODIPY probe, which is located deeper in the membrane.

Structural patterns of the human ABCC4/MRP4 exporter in lipid bilayers rationalize clinically observed polymorphisms.

The ABCC4/MRP4 exporter has a clinical impact on membrane transport of a broad range of xenobiotics. It is expressed at key locations for drug disposition or effects such as in the liver, the kidney and blood cells. Several polymorphisms and mutations (e.g., p.Gly187Trp) leading to MRP4 dysfunction are associated with an increased risk of toxicity of some drugs. So far, no human MRP4 structure has been elucidated, precluding rationalization of these dysfunctions at a molecular level. We constructed an atomistic model of the wild type (WT) MRP4 and the p.Gly187Trp mutant embedded in different lipid bilayers and relaxed them for hundreds of nanoseconds by molecular dynamics simulations. The WT MRP4 molecular structure confirmed and ameliorated the general knowledge about the transmembrane helices and the two nucleotide binding domains. Moreover, our model elucidated positions of three generally unresolved domains: L1 (linker between the two halves of the exporter); L0 (N-terminal domain); and the zipper helices (between the two NBDs). Each domain was thoroughly described in view of its function. The p.Gly187Trp mutation induced a huge structural impact on MRP4, mainly affecting NBD 1 structure and flexibility. The structure of transporter enabled rationalization of known dysfunctions associated with polymorphism of MRP4. This model is available to the pharmacology community to decipher the impact of any other clinically observed polymorphism and mutation on drug transport, giving rise to in silico predictive pharmacogenetics.

Pilot randomized experimental study evaluating isopropyl alcohol and ultraviolet-C radiation in the disinfection of healthcare workers' smartphones.

BACKGROUND: Smartphones in medical settings pose infection risks due to harbouring pathogenic bacteria. AIM: This pilot study assessed the effectiveness duration of sanitization methods, focusing on 70% isopropyl alcohol wipes and ultraviolet-C (UVC) boxes, aiming to obtain preliminary data on the reduction in total bacterial load 3 h post-sanitization. METHODS: A randomized monocentric trial with two intervention arms (wipes and UVC boxes) was designed. As participants, healthcare workers from three wards at Fondazione Policlinico Universitario 'A. Gemelli' IRCCS Hospital were recruited, stratified by ward, and block randomized within each ward to control confounders. FINDINGS: Seventy-one healthcare workers, mostly nurses (62%) were included in the study. Initial bacterial load reduction was significant with both disinfection techniques, but after 3 h both methods showed increased bacterial levels, with wipes displaying potentially higher residual efficacy (P=0.056). To adequately size a trial (89% power, significance level 0.05) for assessing the residual efficacy of alcohol-impregnated wipes compared with UVC boxes at 3 h post-sanitization, 503 professionals per group were required. CONCLUSION: This study highlights the necessity for guidelines on hospital smartphone sanitization and educational initiatives for healthcare workers and patients. Further studies, adequately sized, are necessary to determine optimal sanitization intervals and assess pathogen transmission risks.

Application of recent double-hybrid density functionals to low-lying singlet-singlet excitation energies of large organic compounds.

The present work assesses some recently developed double-hybrid density functionals (B2π-PLYP, PBE0-DH, and PBE0-2) using linear-response Tamm-Dancoff Time-Dependent Density Functional Theory. This assessment is achieved against experimentally derived low-lying excitation energies of large organic dyes of recent interest, including some excitations dominated by charge-transfer transitions. Comparisons are made with some of the best-performing methods established from the literature, such as PBE0 or B3LYP hybrid or the recently proposed B2-PLYP and B2GP-PLYP double-hybrid models, to ascertain their quality and robustness on equal footing. The accuracy of parameter-free or empirical forms of double-hybrid functionals is also briefly discussed. Generally speaking, it turns out that double-hybrid expressions always provide more accurate estimates than corresponding hybrid methods. Double-hybrid functionals actually reach averaged accuracies of 0.2 eV, that can be admittedly considered close to any intended accuracy limit within the present theoretical framework.

Total parenteral nutrition is associated with worse hospital outcomes among elderly diabetic patients: a propensity score matched analysis on discharge records.

Background: Recent trials and reviews have raised question about the safety of total parenteral nutrition (TPN), due to the increased rate of TPN related complications. Diabetic patients are vulnerable to hyperglycaemia, and poor studies have investigated hospital out-comes of diabetic patients requiring TPN. The aim of this study was to evaluate the association of in-hospital mortality, prolonged length of stay and transfer to long-term care facilities among diabetic patients with TPN. Methods: The study considered all hospital admissions of diabetic patients over 65 years of age performed between 2006 and 2015 in Abruzzo Region, Italy. To compare the outcomes of TPN and non-TPN patients, a propensity score matching procedure was performed. Results: A total of 140,556 admissions were analyzed. After matching, 1947 patients were included into the analyses: 649 patients with TPN and 1298 controls. TPN was significantly associated to in-hospital mortality (OR=7.15; 95%CI 5.54-9.22), prolonged LOS (OR=2.78; 95%CI 2.28-3.38) and transfer to LTCF (OR=2.16; 95%CI 1.64-2.85). Discussion: TPN is associated with poor outcomes among elderly diabetic patients in the Italian setting. Being aware of the risk factors among diabetic patients with TPN can be used to anticipate the patients' needs during the admission and the immediate post-discharge period.

Measurements of intrinsic ion Bernstein waves in a tokamak by collective Thomson scattering.

In this Letter we report measurements of collective Thomson scattering (CTS) spectra with clear signatures of ion Bernstein waves and ion cyclotron motion in tokamak plasmas. The measured spectra are in accordance with theoretical predictions and show clear sensitivity to variation in the density ratio of the main ion species in the plasma. Measurements with this novel diagnostic demonstrate that CTS can be used as a fuel ion ratio diagnostic in burning fusion plasma devices.

Gender differences in childhood bmi z-score, alimentary behaviour and lifestyle in a sample of 9-11 children.

BACKGROUND: Child overweight and obesity prevalence has risen substantially in most high-income countries. The prevention of childhood overweight and obesity is a major public health issue. Childhood obesity leads to an increased risk of both physical and mental health consequences,. The aim of this study was to investigate the gender differences in BMI z-score, eating habits, life style and healthy behaviors in children. MATERIALS AND METHODS: With an approach so-called "cluster" method we selected third classes of primary schools. The study was conducted from September 2016 and May 2017 during a school year. Information was collected through a questionnaire filled in by the children with the help of their parents. The biometric data relating to height in meters and weight in kilograms was obtained through the questionnaire. RESULT: A total of 1122 children were included in the current study. 33.9% of boys being overweight compared with 27.8% of girls and 19.1% of boys being obese compared with 12.5% of girls (p<0.001). There were significant differences between boys and girls for physical activity (p=0.004), sedentary behaviors (p<0.001), eating habits (p=0.004). DISCUSSION: In this study, gender differences were analyzed with respect to BMI z-score, eating habits, life style and healthy behaviors in children between 9 and 11 years old. The results of the study confirm the differences that the scientific literature described. Between boys and girls there are different habits that on the one hand can determine differences in the quality of life and future health and on the other hand can be the key to implementing effective and targeted prevention interventions.

Predictors and Trend of Ketoacidosis Hospitalization Rate in Type 2 Diabetes Mellitus Patients from 2006 to 2015 in Abruzzo Region, Italy.

AIMS: This study aimed to assess the trend of hospitalizations for DKA in adult patients with type 2 diabetes mellitus and its associated factors. DESIGN: A retrospective cross-sectional study was performed. Data were collected from hospital discharge records (HDRs) of patients (age ≥18) with either primary or secondary discharge diagnosis for DKA and type 2 diabetes from 2006 to 2015 in Abruzzo region. Age-adjusted hospitalization rates were computed by gender and standardized on the regional population in 2006. A logistic regression model was implemented using presence of DKA as dependent variable. RESULTS: We identified 160,366 HDRs with type 2 diabetes. Out of them, 1611 (1.00%) were due to DKA. The hospitalization rates for DKA increased both for male +115.9 and female +142.8%, from 2006 to 2015. The most significant predictors of DKA were age 18-44 (aOR=4.17), uncontrolled diabetes (aOR=1.79), trauma (aOR=1.38), any infection (aOR=1.68), liver disease (aOR=1.29), fluid and electrolyte disorders (aOR=2.09), psychosis (aOR=1.69). CONCLUSIONS: Trends of DKA in adult patients with type 2 diabetes has been increasing in both male and female. Multimorbidity is an open challenge for public health, therefore better coordination is needed among different specialist consultants to reduce the occurrence of this preventable complication.

Free radical scavenging properties of guaiacol oligomers: a combined experimental and quantum study of the guaiacyl-moiety role.

Natural polyphenols are known to exhibit a lot of different biological properties, including antioxidant activity. For some polyphenols these activities are attributed to the presence of a guaiacol moiety. In the present paper we focus on the role of this moiety. For this purpose nine different compounds were enzymatically synthesized from guaiacol. To elucidate the structure-activity relationship of these polyphenols, DFT-(PCM)B3P86/6-311+G(2d,3pd)//(PCM)B3P86/6-31+G(d,p) calculations supported the experimental DPPH free radical scavenging activities. The antioxidant activities were correlated to (i) O-H BDEs (bond dissociation enthalpies), (ii) BDE(D) (BDE of a second H atom abstraction from the phenoxyradicals), (iii) spin density, (iv) HOMO (highest occupied molecular orbital) distribution, (v) IPs (ionization potentials), (vi) DeltaG and DeltaG(#) free energies of HAT (H atom transfer), and (vii) HAT rate constants. BDE(D) appeared to be the most important descriptor to understand the free radical scavenging ability of these compounds.

Temporal evolution of confined fast-ion velocity distributions measured by collective Thomson scattering in TEXTOR.

Fast ions created in the fusion processes will provide up to 70% of the heating in ITER. To optimize heating and current drive in magnetically confined plasmas insight into fast-ion dynamics is important. First measurements of such dynamics by collective Thomson scattering (CTS) were recently reported [Bindslev, Phys. Rev. Lett. 97, 205005 2006]. Here we extend the discussion of these results which were obtained at the TEXTOR tokamak. The fast ions are generated by neutral-beam injection and ion-cyclotron resonance heating. The CTS system uses 100-150kW of 110-GHz gyrotron probing radiation which scatters off the collective plasma fluctuations driven by the fast-ion motion. The technique measures the projected one-dimensional velocity distribution of confined fast ions in the scattering volume where the probe and receiver beams cross. By shifting the scattering volume a number of scattering locations and different resolved velocity components can be measured. The temporal resolution is 4ms while the spatial resolution is approximately 10cm depending on the scattering geometry. Fast-ion velocity distributions in a variety of scenarios are measured, including the evolution of the velocity distribution after turnoff of the ion heating. These results are in close agreement with numerical simulations.

Prognostic factors in prosthetic rehabilitation of bilateral dysvascular above-knee amputee: is the stump condition an influencing factor?

AIM: The aim of this study was to evaluate the prognostic factors for rehabilitation outcome in bilateral dysvascular lower limb amputees, specifically to ascertain how the stump condition can influence the mobility outcome. METHODS: A retrospective study of 30 selected bilateral above-knee amputees for vascular disease was carried out. Barthel Index (BI) was given and stump condition was assessed at admission and at discharge. Influence of age, comorbidities and stump condition on effectiveness of BI was evaluated. Locomotor Capability Index (LCI) was performed at discharge. Influence of stump problems (pain, flexion, pain with flexion) on LCI was evaluated. RESULTS: At discharge, 25 patients were able to ambulate. Age and pathological conditions of stumps correlated negatively with BI effectiveness. LCI values were higher for patients with ideal stumps and lower for patients with combined stump pain and flexion deformities. Post hoc analysis showed that the principal factor negatively influencing the LCI score was the presence of stump flexion deformities. CONCLUSIONS: In our homogeneous group of bilateral amputees, age reduced the possibility of improving the level of autonomy. Good stump quality is one of the major determinants of mobility outcome. Efforts should be made to minimize stump complications. In particular, incorrect positioning of the stump, which is responsible for hip flexor retraction, should be avoided after surgery.

Paroxysmal atrial fibrillation in myotonic dystrophy type 1 patients: P wave duration and dispersion analysis.

OBJECTIVE: Myotonic dystrophy type 1 (MD1) is characterized by cardiac involvement, in about 80% of case, that predominantly affects the conduction system. Aim of our study was to evaluate the P-wave duration and dispersion (PD) in MD1 patients underwent pacemaker implantation with conserved systolic and diastolic function. PATIENTS AND METHODS: We enrolled 60 MD1 patients (age 51.3 ± 5 years; 11 females) underwent dual chamber pacemaker implantation for various grade of atrioventricular (AV) block. Sixty sex-and age matched non-MD1 subjects were recruited as controls. P-wave duration and dispersion were carefully measured using 12-lead electrocardiogram. RESULTS: Compared with healthy control group, MD1 patients presented increased maximum P wave duration (106.4 ± 20.9 vs 65.9 ± 8.2 ms, p = 0.03) and PD values (40.1 ± 11 vs 27.1 ± 4.2 ms, p = 0.003). No statistically significant difference was found in minimum P wave duration (69.7 ± 11.8 vs 65.4 ± 8.1 ms, p = 0.4). The MD1 patients with paroxysmal atrial fibrillation, compared with MD1 patients without evidence of atrial fibrillation, presented increased maximum P wave duration (108.1 ± 10.4 vs 78.1 ± 7.9 ms, p = 0.001) and PD values (41.1 ± 8.5 vs 33.2 ± 4.2 ms, p = 0.003). Minimum P wave duration (68.4 ± 8.2 vs 67.1 ± 4.9 ms, p = 0.5) didn't differ between the two groups. CONCLUSIONS: Our data showed a significantly increased P wave duration and dispersion in MD1 patients compared with age and sex-matched healthy controls. We showed a statistically significant increase in PD and P max in MD1 patients subgroup with AF compared to MD1 patients with no arrhythmias.

Basal 17beta-estradiol did not correlate with ovarian response and in vitro fertilization treatment outcome.

OBJECTIVE: To verify the correlation of basal 17beta-E(2) with ovarian response to stimulation and outcome of in vitro fertilization (IVF). DESIGN: Retrospective observational study. SETTING: The Assisted Conception Unit, University College London Hospitals. PATIENT(S): Three hundred five women undergoing IVF and IVF with intracytoplasmic sperm injection. INTERVENTION(S): Basal follicle-stimulating hormone (FSH) and 17beta-E(2) were assessed. The cutoff level for day 2 E(2) established was 250 pmol/L. Each patient was noted for below (group A) or above (group B) the cutoff point according to her basal E(2) level. MAIN OUTCOME MEASURE(S): Basal E(2), age, duration of infertility, cycle day 2 FSH, number of ampules of gonadotropin used, number of days of stimulation, number of retrieved oocytes, fertilization rate, number of embryos transferred, number of cycles with embryo freezing, cancellation rate, clinical pregnancy rate, and implantation rate were compared between the two groups. RESULT(S): No differences were found between group A and group B in the number of oocytes retrieved (8.8 +/- 4.2 vs. 9.3 +/- 4.8), embryos transferred (2.5 +/- 0.8 vs. 2.7 +/- 0.7), cancellation (9.1% vs. 6.9%), pregnancy (24.8% vs. 30%), and implantation rate (12.3% vs. 15.6%). Correlation coefficient and coefficient of determination showed no significant correlation between basal E(2) and the number of oocytes retrieved, age, and basal FSH. CONCLUSION(S): In our study population, basal E(2) was not a sensitive predictor of ovarian response to stimulation and did not correlate with IVF outcome.

Red blood cell energy metabolism during cardiopulmonary bypass.

BACKGROUND: During cardiopulmonary bypass (CPB) an intracellular ATP deficit could theoretically play a role in changes of erythrocyte shape and deformability caused by mechanical trauma. We therefore studied erythrocyte energy metabolism in 12 patients undergoing normothermic CPB for myocardial revascularization. METHODS: Blood samples were collected prior to and 45 minutes after CPB beginning and analyzed for erythrocyte ATP, ADP, and AMP and their metabolites, erythrocyte NAD and NADP, plasma and whole blood lactate (Lact(p) and Lact(b) respectively), and whole blood pyruvate (Pyr(b)). RESULTS: Values were expressed as mean +/- standard deviation or median (lower and higher quartiles) on the ground of a test for normality. During CPB erythrocyte nucleotides and their metabolites did not change significantly (ATP: 60.2+/-12.1 vs. 68.3+/-13.0; ADP: 12.2+/-3.6 vs. 12.0+/-3.1; AMP: 0.43+/-24 vs. 0.44+/-0.26; adenosine: 0.063 (0.034-0.203) vs. 0.77 (0.032-0.221); inosine: 0.064 (0.023-0.072) vs. 0.075 (0.025-0.111); hypoxanthine: 0.330+/-0.272 vs. 0.367+/-0.223; xanthine: 0.193+/-0.090 vs. 0.220+/-0.095; NAD: 3.149+/-0.743 vs. 3.358+/-0.851; values in microM/mM packed red blood cell hemoglobin) while NADP increased (2.110+/-0.390 vs. 2.433+/-0.288 microM/mM packed red blood cell hemoglobin; p<0.05). Ringer lactate, with which the extracorporeal circuit was primed, caused Lact(p) to increase (1.87+/-0.81 vs. 3.27+/-1.15 mM/l; p<0.01). Some lactate entered erythrocytes since Lact(p)/Lact(b) ratio did not change (1.09+/-0.25 vs. 1.07+/-0.23) and some was transformed into pyruvate since Pyr(b) increased [62.9 (30.3-73.3) vs. 100.5 (61.0-146.9) microM/l; p<0.01]. Lact(b)/Pyr(b) ratio did not change significantly [22.6 (16.1-40.5) vs. 27.9 (17.5-35.2)] so that NAD/NADH ratio and, consequently, the rate of glycolysis were unlikely to change too. CONCLUSIONS: Erythrocyte energy metabolism is not affected by CPB, at least during the period of time taken into account in this study.

Anesthetic management of pheochromocytoma in a long term hemodialysed patient.

The anesthetic management of a hemodialyzed patient with a dopamine producing pheochromocytoma is described. A 56-years old man underwent surgical procedure the day after hemodialysis. Prior to intervention adrenal cortex hormones were normal as well as other endocrine variables (T3-T4-TSH-cortisol-ACTH-parathyroid hormone); epinephrine and norepinephrine, were in a normal range while dopamine was elevated (185 pg/ml). Preoperatively the patient was alpha-blocked with oral phenoxybenzamine (20 mg/day). A balanced anesthesia was performed (isoflurane and fentanyl). Plasma catecholamines were determined. During the induction of anesthesia and before tracheal intubation phentolamine and labetalol were injected till 3.4 mg and 50 mg total dose respectively. During surgical manipulation a nitroglycerin infusion was started (1.5 gamma/kg/min) and after tumor resection dopamine was given till 15 gamma/kg/min. Hormonal values increased in presence of unchanged hemodynamic parameters, likely due to alpha and/or beta blockade. In this case report our problem was especially fluid replacement after tumor resection, because of renal failure. On the basis of CVP and PCWP values, fluid treatment and dopamine infusion allowed to achieve an adequate preload. A sufficient level of analgesia and an efficient alpha blockade may assure hemodynamic stability also in a so compromised patient status.

Resolving the bulk ion region of millimeter-wave collective Thomson scattering spectra at ASDEX Upgrade.

Collective Thomson scattering (CTS) measurements provide information about the composition and velocity distribution of confined ion populations in fusion plasmas. The bulk ion part of the CTS spectrum is dominated by scattering off fluctuations driven by the motion of thermalized ion populations. It thus contains information about the ion temperature, rotation velocity, and plasma composition. To resolve the bulk ion region and access this information, we installed a fast acquisition system capable of sampling rates up to 12.5 GS/s in the CTS system at ASDEX Upgrade. CTS spectra with frequency resolution in the range of 1 MHz are then obtained through direct digitization and Fourier analysis of the CTS signal. We here describe the design, calibration, and operation of the fast receiver system and give examples of measured bulk ion CTS spectra showing the effects of changing ion temperature, rotation velocity, and plasma composition.

Temporally resolved plasma composition measurements by collective Thomson scattering in TEXTOR (invited).

Fusion plasma composition measurements by collective Thomson scattering (CTS) were demonstrated in recent proof-of-principle measurements in TEXTOR [S. B. Korsholm et al., Phys. Rev. Lett. 106, 165004 (2011)]. Such measurements rely on the ability to resolve and interpret ion cyclotron structure in CTS spectra. Here, we extend these techniques to enable temporally resolved plasma composition measurements by CTS in TEXTOR, and we discuss the prospect for such measurements with newly installed hardware upgrades for the CTS system on ASDEX Upgrade.

Elevation angle alignment of quasi optical receiver mirrors of collective Thomson scattering diagnostic by sawtooth measurements.

Localized measurements of the fast ion velocity distribution function and the plasma composition measurements are of significant interest for the fusion community. Collective Thomson scattering (CTS) diagnostics allow such measurements with spatial and temporal resolution. Localized measurements require a good alignment of the optical path in the transmission line. Monitoring the alignment during the experiment greatly benefits the confidence in the CTS measurements. An in situ technique for the assessment of the elevation angle alignment of the receiver is developed. Using the CTS diagnostic on TEXTOR without a source of probing radiation in discharges with sawtooth oscillations, an elevation angle misalignment of 0.9° was found with an accuracy of 0.25°.

Design and performance of the collective Thomson scattering receiver at ASDEX Upgrade.

Here we present the design of the fast-ion collective Thomson scattering receiver for millimeter wave radiation installed at ASDEX Upgrade, a tokamak for fusion plasma experiments. The receiver can detect spectral power densities of a few eV against the electron cyclotron emission background on the order of 100 eV under presence of gyrotron stray radiation that is several orders of magnitude stronger than the signal to be detected. The receiver down converts the frequencies of scattered radiation (100-110 GHz) to intermediate frequencies (IF) (4.5-14.5 GHz) by heterodyning. The IF signal is divided into 50 IF channels tightly spaced in frequency space. The channels are terminated by square-law detector diodes that convert the signal power into DC voltages. We present measurements of the transmission characteristics and performance of the main receiver components operating at mm-wave frequencies (notch, bandpass, and lowpass filters, a voltage-controlled variable attenuator, and an isolator), the down-converter unit, and the IF components (amplifiers, bandpass filters, and detector diodes). Furthermore, we determine the performance of the receiver as a unit through spectral response measurements and find reasonable agreement with the expectation based on the individual component measurements.