Dependence on the thermodynamic state of self-diffusion of pseudo-hard-sphere and Lennard-Jones potentials.

Self-diffusion D in a system of particles that interact with a pseudo-hard-sphere or a Lennard-Jones potential is analyzed. Coupling with a solvent is represented by a Langevin thermostat, characterized by the damping time t_{d}. The hypotheses that D=D_{0}φ is proposed, where D_{0} is the small concentration diffusivity and φ is a thermodynamic function that represents the effects of interactions as concentration is increased. Molecular dynamics simulations show that different values of the noise intensity modify D_{0}, but do not have an effect on φ. This result is consistent with the assumption that φ is a thermodynamic function since the thermodynamic state is not altered by the presence of damping and noise.

Diffusion on a lattice: Transition rates, interactions, and memory effects.

We analyze diffusion of particles on a two-dimensional square lattice. Each lattice site contains an arbitrary number of particles. Interactions affect particles only in the same site, and are macroscopically represented by the excess chemical potential. In a recent work, a general expression for transition rates between neighboring cells as functions of the excess chemical potential was derived. With transition rates, the mean-field tracer diffusivity, D^{MF}, is immediately obtained. The tracer diffusivity, D=D^{MF}f, contains the correlation factor f, representing memory effects. An analysis of the joint probability of having given numbers of particles at different sites when a force is applied to a tagged particle allows an approximate expression for f to be derived. The expression is applied to soft core interaction (different values for the maximum number of particles in a site are considered) and extended hard core.

Application of the Widom insertion formula to transition rates in a lattice.

We consider diffusion of particles on a lattice in the so-called dynamical mean-field regime (memory effects are neglected). Interactions are local, that is, only among particles at the same lattice site. It is shown that a statistical mechanics analysis that combines detailed balance and Widom's insertion formula allows for the derivation of an expression for transition rates in terms of the excess chemical potential. The rates reproduce the known dependence of self-diffusivity as the inverse of the thermodynamic factor. Soft-core interactions and general forms of the excess chemical potential (linear, quadratic, and cubic with the density) are considered.

Causes of Death and Survival in Alcoholic Cirrhosis Patients Undergoing Liver Transplantation: Influence of the Patient's Clinical Variables and Transplant Outcome Complications.

BACKGROUND: Clinical and molecular mechanisms involved in the cause and time of death of alcoholic cirrhosis (AC) patients undergoing liver transplantation (LT) are not entirely understood. In sudden death cases, judicial autopsy practice is mandatory for determining the cause and circumstances of death. The medico-legal autopsy data are essential for helping health authorities to guide future public health activities, assess the effectiveness of health systems, and adopt the necessary preventive measures to improve and adapt the treatments in order to increase these patients' survival. OBJECTIVE: Our study aimed to determine the different clinical and sociodemographic causes that influence the different causes of death and the short- and long-term survival of AC patients undergoing liver transplantation. METHODS: A total of 122 deceased AC patients undergoing LT were analyzed at different times post-transplantation. The main pre- and post-transplant complications were analyzed in relation to the cause of death and the patient's survival, as well as the causes and time at which the patient's death occurred. RESULTS: A total of 53.3% of non-sudden death was observed. A large number of the deaths of AC patients undergoing transplantation were due to non-sudden death, sepsis, and graft failure (GF), the main causes of death in the sample being similar in both sexes. In non-sudden deaths, there were no significant differences between the death rates either related or not related to the liver transplant. Sepsis was the main cause, with the highest percentage (21.3%) of mortality, followed by GF (18.9%) and multiorgan failure (15.6%) at ten years. Furthermore, our results showed how pre-transplant clinical complications, such as viral infections and encephalopathy, influence the age at which multiorgan failure occurs in the transplanted patient. CONCLUSION: Multiorgan failure is the leading cause of sudden death, with higher mortality during the first year after transplantation, followed by sepsis and GF. Our results show the vulnerability of AC patients, both in the hospital period after the transplant and outside.

Identification of peripheral CD154+ T cells and HLA-DRB1 as biomarkers of acute cellular rejection in adult liver transplant recipients.

Decreasing graft rejection and increasing graft and patient survival are great challenges facing liver transplantation (LT). Different T cell subsets participate in the acute cellular rejection (ACR) of the allograft. Cell-mediated immunity markers of the recipient could help to understand the mechanisms underlying acute rejection. This study aimed to analyse different surface antigens on T cells in a cohort of adult liver patients undergoing LT to determine the influence on ACR using multi-parametric flow cytometry functional assay. Thirty patients were monitored at baseline and during 1 year post-transplant. Two groups were established, with (ACR) and without (NACR) acute cellular rejection. Leukocyte, total lymphocyte, percentages of CD4+ CD154+ and CD8+ CD154+ T cells, human leukocyte antigen (HLA) mismatch between recipient-donor and their relation with ACR as well as the acute rejection frequencies were analysed. T cells were stimulated with concanavalin A (Con-A) and surface antigens were analysed by fluorescence activated cell sorter (FACS) analysis. A high percentage of CD4+ CD154+ T cells (P = 0·001) and a low percentage of CD8+ CD154+ T cells (P = 0·002) at baseline were statistically significant in ACR. A receiver operating characteristic analysis determined the cut-off values capable to stratify patients at high risk of ACR with high sensitivity and specificity for CD4+ CD154+ (P = 0·001) and CD8+ CD154+ T cells (P = 0·002). In logistic regression analysis, CD4+ CD154+ , CD8+ CD154+ and HLA mismatch were confirmed as independent risk factors to ACR. Post-transplant percentages of both T cell subsets were significantly higher in ACR, despite variations compared to pretransplant. These findings support the selection of candidates for LT based on the pretransplant percentages of CD4+ CD154+ and CD8+ CD154+ T cells in parallel with other transplant factors.

[Sleep and academic performance in university students: a systematic review]. / Sueño y rendimiento académico en estudiantes universitarios: revisión sistemática.

INTRODUCTION: University students tend to suffer from problems of sleep regularity, quantity and quality, which can affect their academic performance. These problems are related to changes typical of the phase of the life cycle in which they find themselves due to maturational, psychosocial development (associated with the processes of individuation and socialisation) and academic factors. The study of the relationship between sleep and academic performance in university students is an area of research of growing interest, which has started to be studied over the last two decades. AIM: To conduct a systematic review of the existing literature on the relationship between sleep and academic performance in university students. SUBJECTS AND METHODS: The articles included in the PubMed database were selected, following the PRISMA guidelines. Studies evaluating samples of subjects with an average age between 18 and 26 years, published in English or Spanish during the period 2000-2019 were included. Subsequently, the quality of the selected articles was evaluated according to the STROBE standard. RESULTS: Thirty studies were identified, which were grouped according to different aspects of sleep: drowsiness, duration, experience of total sleep deprivation, sleep quality, chronotype, regularity and sleep disorders. CONCLUSION: The results of these studies suggest that inadequate sleep has a negative effect on the academic performance of university students.

TITLE: Sueño y rendimiento académico en estudiantes universitarios: revisión sistemática.Introducción. Los estudiantes universitarios tienden a padecer problemas de regularidad, cantidad y calidad de sueño, que pueden afectar a su rendimiento académico. Estos problemas se relacionan con cambios propios de la fase del ciclo vital en la que se encuentran debido a diversos factores: madurativos, del desarrollo psicosocial (asociados con los procesos de individuación y socialización) y académicos. El estudio de la relación entre el sueño y el rendimiento académico en estudiantes universitarios es un área de investigación de interés creciente, que ha empezado a ser objeto de estudio en las últimas dos décadas. Objetivo. Revisión sistemática de la bibliografía existente sobre la relación del sueño y el rendimiento académico en los estudiantes universitarios. Sujetos y métodos. Se seleccionaron los artículos recogidos en la base de datos PubMed, siguiendo las directrices PRISMA. Se incluyeron los estudios que valoraban muestras de sujetos con una edad media entre 18 y 26 años, publicados en inglés o castellano, durante el período 2000-2019. Posteriormente, se evaluó la calidad de los artículos seleccionados siguiendo la normativa STROBE. Resultados. Se identificaron 30 estudios, que fueron agrupados según distintos aspectos del sueño: somnolencia, duración, experiencia de privación total de sueño, calidad de sueño, cronotipo, regularidad y trastornos del sueño. Conclusión. Los resultados de estos estudios sugieren que un sueño inadecuado afecta negativamente al rendimiento académico de los estudiantes universitarios.

Hypnotic communication for periprocedural analgesia during transcatheter ablation of atrial fibrillation.

INTRODUCTION: Hypnosis is a therapeutic strategy for pain control. We aimed at investigating the use of this technique in a large population undergoing atrial fibrillation (AF) ablation. METHODS: 70 consecutive AF patients referred for transcatheter ablation, underwent hypnotic communication for periprocedural analgesia (Group A), were compared with 70 patients undergoing conventional analgesia (Group B). Procedural data, anxiety, perceived pain, perceived procedural duration and the dosages of administered analgesic drugs were compared using validated score scales. RESULTS: Hypnotic communication (Group A) resulted in a significant procedural-related anxiety reduction (Pre procedural 4.7 ±â€¯2.9 Vs Intra Procedural 0.8 ±â€¯1.2, P < 0.001) and perceived procedural duration (Real length 108 ±â€¯33 min Vs Perceived Length 77 ±â€¯39 min, P < 0.001). Group A patients reported a painless procedure in 78% (Pain scale ≤2). Regarding analgesic drug, Group A used only Fentanyl and Paracetamol. The Fentanyl dosage was similar in Group A and B (mean 0.142 Vs 0.146 mg, P = 0.65) while higher Paracetamol dosage was reported in Group A (mean 853 Vs 337 mg, P < 0.001). Group B also used Midazolam (mean 1.8 mg), Propofol (mean 43.8 mg) and narcosis was required in 2 patients. Total radiofrequency (RF) delivered time did not differ between the two groups (mean 28.9 Vs 27.6 min, P = 0.623) as well as mean RF power (mean 35.3 Vs 35.5 W, P = 0.424). No complications occurred. CONCLUSION: Hypnotic communication during AF ablation was related to a significant reduction of intra-procedural anxiety, perceived pain, procedural analgesic drugs dosage and perceived procedural duration without affecting total RF delivered time and procedural safety.

Dynamic vaccination in partially overlapped multiplex network.

In this work we propose and investigate a strategy of vaccination which we call "dynamic vaccination." In our model, susceptible people become aware that one or more of their contacts are infected and thereby get vaccinated with probability ω, before having physical contact with any infected patient. Then the nonvaccinated individuals will be infected with probability ß. We apply the strategy to the susceptible-infected-recovered epidemic model in a multiplex network composed by two networks, where a fraction q of the nodes acts in both networks. We map this model of dynamic vaccination into bond percolation model and use the generating functions framework to predict theoretically the behavior of the relevant magnitudes of the system at the steady state. We find a perfect agreement between the solutions of the theoretical equations and the results of stochastic simulations. In addition, we find an interesting phase diagram in the plane ß-ω, which is composed of an epidemic and a nonepidemic phase, separated by a critical threshold line ß_{c}, which depends on q. As q decreases, ß_{c} increases, i.e., as the overlap decreases, the system is more disconnected, and therefore more virulent diseases are needed to spread epidemics. Surprisingly, we find that, for all values of q, a region in the diagram where the vaccination is so efficient that, regardless of the virulence of the disease, it never becomes an epidemic. We compare our strategy with random immunization and find that, using the same amount of vaccines for both scenarios, we obtain that the spread of disease is much lower in the case of dynamic vaccination when compared to random immunization. Furthermore, we also compare our strategy with targeted immunization and we find that, depending on ω, dynamic vaccination will perform significantly better and in some cases will stop the disease before it becomes an epidemic.

Cell-Mediated Immunity (CMI) as the Instrument to Assess the Response Against the Allograft: Present and Future.

The concept of Cell-Mediated Immunity (CMI) monitoring in transplantation has gained popularity over time and is now a reality. Significant technological advances have enabled us to test for multiple molecules and cells implicated in inflammatory or suppressive reactions to the graft. The main challenge nowadays is whether clinicians can use the information provided by the measurement of such markers to predict post-transplant outcome. To date a wide range of markers have been identified as promising biomarkers in the monitoring of individual responses to immunosuppression or in the determination of patient alloreactivity to the graft, which could prove helpful in the assessment of the occurrence of an adverse/side effect. Before these biomarkers are deemed suitable, standardisation of the methodology and validation of its feasibility in clinical outcome remains an ongoing challenge. The research community is currently facing a large effort towards the implementation of a standard methodology that is both highly reproducible and can reduce inter-laboratory variability, therefore generating consistency with data. The aim of this manuscript is to review the current literature regarding CMI monitoring in the field of solid organ transplantation (SOT), undertaking a comprehensive study of the latest findings. In addition, based upon current literature, we aim to propose a comprehensive classification of biomarkers to further aid our current understanding, taking in to account the type of transplantation, when its measurement should be applied and which would be the most suitable biomarker to assess.

Three new HLA class I alleles with synonymous mutations: HLA-A*03:01:62, -C*07:02:82 and -C*12:03:42.

Three new HLA class I alleles with synonymous mutations were identified.

Cascading Failures in Interdependent Networks with Multiple Supply-Demand Links and Functionality Thresholds.

Various social, financial, biological and technological systems can be modeled by interdependent networks. It has been assumed that in order to remain functional, nodes in one network must receive the support from nodes belonging to different networks. So far these models have been limited to the case in which the failure propagates across networks only if the nodes lose all their supply nodes. In this paper we develop a more realistic model for two interdependent networks in which each node has its own supply threshold, i.e., they need the support of a minimum number of supply nodes to remain functional. In addition, we analyze different conditions of internal node failure due to disconnection from nodes within its own network. We show that several local internal failure conditions lead to similar nontrivial results. When there are no internal failures the model is equivalent to a bipartite system, which can be useful to model a financial market. We explore the rich behaviors of these models that include discontinuous and continuous phase transitions. Using the generating functions formalism, we analytically solve all the models in the limit of infinitely large networks and find an excellent agreement with the stochastic simulations.

Pretransplant CD28 Biomarker (Levels of Expression and Quantification of Molecules per Cell) in Peripheral CD4+ T Cells Predicts Acute Rejection Episodes in Liver and Kidney Recipients.

BACKGROUND: Acute rejection (AR) remains a significant cause of graft loss. Better approaches to predict AR are being investigated. Surface CD28 protein is essential for T-cell proliferation and survival as well as cytokine production. PATIENTS AND METHODS: Pretransplant CD4+CD28+ peripheral T cells were examined in 30 liver recipients (LRs) and 31 kidney recipients (KRs) by flow cytometry. RESULTS: Pretransplant CD4+CD28+ T cells in LRs were significantly lower in rejectors than nonrejectors (P = .002). Furthermore, the total number of CD28 molecules per cell in LRs (P = .02) as well as KRs (P = .047) was significantly lower in rejectors than nonrejectors. The healthy group did not display differences when compared with patients with end-stage liver disease or renal failure; however, stratification analysis displayed higher levels of CD4+CD28+ when compared with rejected LRs (P = .04) but not KRs. CD28 levels <41.94% were able to discriminate LRs at high risk of AR (P = .003). Similarly, a total number of CD28 molecules ≤8359 (P = .031) in LRs and ≤7669 (P = .046) in KRs correlated with high risk of AR. CONCLUSION: The preliminary results presented herein exhibit a fast and noninvasive method that assists clinicians to prevent AR by monitoring CD4+CD28+ peripheral T cells.

Report From the First and Second Spanish Killer Immunoglobulin-Like Receptor Genotyping Workshops: External Quality Control for Natural Killer Alloreactive Donor Selection in Haploidentical Stem Cell Transplantation.

An important factor affecting the success in the setting of related haploidentical hematopoietic stem cell transplantation (HSCT) is the graft-versus-leukemia effect mediated by natural killer (NK) cells when the donor displays NK alloreactivity versus the recipient. NK cell function is regulated by killer immunoglobulin-like receptors (KIR) and it has been described that donor KIR genotype influences transplantation outcome. This has led to a requirement of laboratories to have a quality assurance program for validation and control of their KIR genotyping methods. The goal of the 1st and 2nd Spanish KIR Genotyping Workshops was to provide an external proficiency testing program in KIR genotyping for Spanish immunology and transplant laboratories. These workshops were conducted during the years 2014-2016 and consisted of 17 participating laboratories typing a set of 20 samples. The presence/absence of 16 mandatory KIR loci (2DL1, 2DL2, 2DL3, 2DL4, 2DL5, 2DS1, 2DS2, 2DS3, 2DS4, 2DS5, 2DP1, 3DL1, 3DL2, 3DL3, 3DS1, and 3DP1) was evaluated per sample. Methods for KIR genotyping included polymerase chain reaction with the use of sequence-specific primers and sequence-specific oligoprobes. Consensus typing was reached in all samples, and the performance of laboratories in external proficiency testing was satisfactory in all cases. The polymorphism detected in the small sample studied in both workshops is indicative of an ample variety of KIR gene profiles in the Spanish population.

Cascading failures in interdependent networks with finite functional components.

We present a cascading failure model of two interdependent networks in which functional nodes belong to components of size greater than or equal to s. We find theoretically and via simulation that in complex networks with random dependency links the transition is first order for s≥3 and continuous for s=2. We also study interdependent lattices with a distance constraint r in the dependency links and find that increasing r moves the system from a regime without a phase transition to one with a second-order transition. As r continues to increase, the system collapses in a first-order transition. Each regime is associated with a different structure of domain formation of functional nodes.

Molecular characterisation and antifungal susceptibility of clinical Cryptococcus deuterogattii (AFLP6/VGII) isolates from Southern Brazil.

Cryptococcosis, caused by Cryptococcus gattii sensu lato, is an emerging disease that was initially found in (sub)tropical regions but recently expanded to temperate regions. Cryptococcus gattii s.l. infections are mostly encountered in healthy individuals, frequently affecting both lungs and the central nervous system (CNS). Usually, C. gattii s.l. is less susceptible to antifungal compounds than its counterpart, C. neoformans s.l. We studied 18 clinical C. gattii s.l. isolates with amplified fragment length polymorphism (AFLP) fingerprinting, mating-typing, multi-locus sequence typing (MLST) and antifungal susceptibility testing. All isolates were C. deuterogattii (genotype AFLP6/VGII), 14 were mating-type α and four were type a. Amphotericin B, itraconazole, voriconazole, posaconazole and isavuconazole showed high activity, with minimum inhibitory concentration (MIC) ranges of 0.063-0.25, 0.031-0.25, 0.031-0.25, 0.031-0.25 and <0.016-0.25 µg mL-1, respectively. Fluconazole and flucytosine had high geometric mean MICs of 2.07 and 3.7 µg mL-1, respectively. Most cases occurred in immunocompetent patients (n = 10; 55.6 %) and CNS involvement was the most common clinical presentation (n = 14; 77.8 %). Three patients (16.7 %) showed sequelae, hyperreflexia, dysarthria, diadochokinesia, anosmia and upper limb weakness. In conclusion, all infections were caused by C. deuterogattii (AFLP6/VGII) and the majority of patients were immunocompetent, with the CNS as the most affected site. All antifungal drugs had high in vitro activity against C. deuterogattii isolates, except fluconazole and flucytosine.

Recovery of Interdependent Networks.

Recent network research has focused on the cascading failures in a system of interdependent networks and the necessary preconditions for system collapse. An important question that has not been addressed is how to repair a failing system before it suffers total breakdown. Here we introduce a recovery strategy for nodes and develop an analytic and numerical framework for studying the concurrent failure and recovery of a system of interdependent networks based on an efficient and practically reasonable strategy. Our strategy consists of repairing a fraction of failed nodes, with probability of recovery γ, that are neighbors of the largest connected component of each constituent network. We find that, for a given initial failure of a fraction 1 - p of nodes, there is a critical probability of recovery above which the cascade is halted and the system fully restores to its initial state and below which the system abruptly collapses. As a consequence we find in the plane γ - p of the phase diagram three distinct phases. A phase in which the system never collapses without being restored, another phase in which the recovery strategy avoids the breakdown, and a phase in which even the repairing process cannot prevent system collapse.

Publisher's Note: Cascading failures in interdependent networks with finite functional components [Phys. Rev. E 94, 042304 (2016)].

This corrects the article DOI: 10.1103/PhysRevE.94.042304.

Activated Regulatory T Cells Expressing CD4(+)CD25(high)CD45RO(+)CD62L(+) Biomarkers Could Be a Risk Factor in Liver Allograft Rejection.

Activated regulatory T cells (aTregs) are nowadays a hot topic in organ transplantation to establish their role during acute rejection (AR) episodes. The aim of this multi-center study was to monitor the frequency of aTregs within the first year after transplantation in a cohort of first-time liver transplant recipients enrolled from 2010 to 2012. aTregs frequency was analyzed by means of flow cytometry. Patients who had AR showed higher levels of aTregs during first year after transplantation in comparison with patients who did not have higher levels. High levels of aTregs in liver recipients might be used as a biomarker of AR; however, further studies must be done to address the potential role of aTregs as biomarkers of AR in liver transplantation.