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Abstract: The electrospinning of urethane based low molecular weight polymers differing only in the nature of the hydrogen bonding end-groups has been investigated. For the end-groups with the lowest binding constants at maximum solubility only droplets, are produced at the electrode; in contrast, increasing the binding constant of the end-group results in electrospun fibres being produced. The properties of the fibres produced are subject to changes in solvent, concentration and temperature. Typical diameters for these fibres were found to be some 10s of μm, rather than the sub-micron dimensions often produced in electrospinning systems. Such diameters are related to the high initial concentrations required; this also may influence the rate of solvent removal and preferential surface solidification which feature in these examples. A simple theoretical model is used to relate the association constant to the molecular weight required for fibre formation; significantly lower levels of association are required for higher molecular weight macromonomers compared to smaller molecular systems. [Copyright &y& Elsevier]

Introduction Along with death engraftment, in recent years, antibody-mediated damage has been identified as the leading cause of loss of kidney transplants. Despite the recognition of the role of the B-lymphocyte subpopulation in the development of both tolerance and rejection, little is known about the trigger mechanisms and effectors of this humoral response. Background We analyzed the relationship between B lymphocyte subpopulations and levels of B-cell–activating factor (BAFF) with the histological findings in biopsies of renal transplantation. Material and Methods We selected 35 patients whose kidney transplant biopsy was performed between January and November 2015. The biopsy specimens were classified according to Banff criteria. At the moment of the biopsy BAFF levels and B-lymphocyte subpopulations in blood were measured using enzyme-linked immunosorbent assay (ELISA) and using flow cytometry, respectively. Results Mean BAFF levels were 493 ± 245 pg/mL. The median performance of biopsy post-transplantation was 12.9 (11.7-23.9) months. BAFF levels correlated with pretransplantation antibodies ( r = 0.523; P = .002) but not with kidney function. In biopsies performed more than 1 year after transplantation BAFF levels correlated with the severity of chronic glomerular (cg) involvement ( r = 0.625; P = .003). Histological variables related to antibody-mediated injury selected by principal component analysis (glomerulitis, peritubular capillary, and chronic glomerulopathy) related to BAFF levels (B factor, 116; 95% confidence interval [CI], 12–220; P = .029). Biopsy specimens with transplant glomerulopathy (TG) showed lower levels of circulating naive CD19 + subpopulation, IgD+, and CD27- (32.7 ± 28.1 vs 87.9 ± 79.1; P = .017) compared with biopsy specimens without TG. Conclusions Elevated levels of BAFF are associated with increased presence and severity of TG and a set of variables related to antibody-mediated histological damage. TG is associated with changes in circulating B-lymphocyte subpopulations that could contribute to its pathogenesis. [ABSTRACT FROM AUTHOR]

The effect of autohydrolysis (AH) temperature (165 °C, 195 °C, 225 °C) on the structure, purity, and recovery yield of the cellulose residue isolated after additional alkaline and bleaching steps from wheat straw, was investigated. The processes were quantified for mass yields in the different steps and for antioxidants and sugars release during AH. AH at 195 °C allowed for the highest cellulose residue yield (83.5%) with purity (∼70%) and structure similar to the other residues. FTIR and XRD analyses showed straw cellulose (SC) with a type II polymorphism and crystallinity index increasing with AH temperature. SC obtained at the end of the entire fractionation process (SC-195 °C) starting from AH residue-195 °C was tested as a reinforcing agent in different percentage (0, 2 and 5% by weight) in poly(butylene adipate- co -terephthalate) (PBAT) films. The Young's modulus of the films increased by ∼17% with 5 wt% cellulose, while tensile strength and elongation at break decreased. [Display omitted] • Investigation of autohydrolysis pretreatment for cellulose recovery from wheat straw • Effect of autohydrolysis on cellulose purity and structure • Cellulose from autohydrolysis tested as a reinforcing agent for PBAT films • Improvement of Young's module of PBAT films with cellulose [ABSTRACT FROM AUTHOR]

Aims. – To examine the different components of fatigue.Current knowledge. – Numerous works have shown that enhanced physical load could result in fatigue which is characterised by a decrease in physical and mental performance. Fatigue is caused by an energy imbalance between nutritional intake and energy expenditure due to muscular work. Supplementary chronobiological and psychological stress facilitates fatigue. The general effect of these different factors is responsible for hormonal and immune changes.Points of view and plans. – The main hormonal axes, which respond to fatigue, are the gonadal and somatotrope axes, the hypothalamo–pituitary–adrenal axis, the medullo-sympathetic axis, and the neurotransmitters. The metabolic and hormonal changes during fatigue are responsible of important modifications, both of some central neurotransmitters and of some immune functions. Several data underline that increases and decreases in serotonergic activity during prolonged exercise hasten and delay fatigue. It has been also shown that there is a functional link between the hormonal response and the immune status decrease, which is under influence of muscle inflammation because of exercise excess. [Copyright &y& Elsevier]

Aims. – To examine the effects of physical exercise on leptin levels.Current knowledge. – Leptin plays a key role in the regulation of energy balance. Leptin acts as a satiety factor informing the central nervous system of changes in the amount of adipose tissue in the body and plays a role in the lipid metabolism. Exercise may contribute to the regulation of circulating leptin levels and leptin action. It would be a threshold in energy expenditure to reach during acute exercise (~800 kcal) to reduce leptin levels. A short or long-term training (< or > to 12 weeks) will not modify basal leptin levels without changes in body composition (body fat reduction). Caloric restriction is necessary during training to modify leptin levels.Points of views and plans. – Physiological mechanisms are now proposed to explain exercise-induced changes in leptin levels. Exercise-induced reduction in insulin levels and elevation in circulating catecholamines could be considered as mediators of leptin response. Determination of changes in leptin levels during exercise could represent an important indicator of nutritional status, body composition, and reproductive disorders. It would be of interest during the overtraining syndrome. [Copyright &y& Elsevier]

Highlights: [•] A reduced-complexity kinetic model for the FTS over Co–Re/Al2O3 was formulated. [•] The model described well the catalyst performance for CO conversions below 50%. [•] Strong diffusional limitations develop at high space-times and CO conversions. [•] Isothermal plug-flow model is valid for microreactors at moderate CO conversion. [•] Transport effects may become an issue for the FTS in microstructured reactors. [ABSTRACT FROM AUTHOR]

Abstract: Serotonin (5-HT) is a neurotransmitter and an immune modulator. At the periphery, the serotonergic system appears to possess a regulatory activity via 5-HT1B receptors. The present study investigated the effects of a 5-day military course following 3 weeks of combat training on the functional activity of 5-HT1B/1D receptors in peripheral blood lymphocytes of male soldiers. The results of [35S]GTPγS binding assays showed that h5-HT1B/1D receptors were desensitized after the training program, although serum 5-HT was unchanged. These data suggest the existence of a control on T cells mediated through h5-HT1B/1D receptors leading cytokine production modulation after a physical training. [Copyright &y& Elsevier]

Abstract: Objectives. – This study assesses on patients with myophosphorylase deficiency (McArdle’s disease) the effects of a moderate aerobic training program (8 weeks, 3 sessions of 45 minutes per week at 60–70% of maximal heart rate) on the physiological response during exercise. Methods. – The cardiorespiratory, electromyographic (EMG) and metabolic responses are evaluated on four patients before and after training to an acute exercise (1 h) on an ergometric bicycle (20–35 Watts) followed by 30 minutes recovery. Results. – Before training, the EMG activity is very high during the first ten minutes of exercise while oxygen uptake (VO2) remains stable over the 60 minutes of exercise. The heart rate (FC) and the rate of perceived exertion (RPE) are markedly increased. Patients highly use circulatory glucose and free fatty acids for oxidation. During exercise, the 8-week training program reduces EMG activity, FC, RPE and the time of second-wind apparition whereas it has any effect on VO2. At the end of exercise recovery, patients use more circulatory glucose and product lactate; moreover, their respiratory exchange ratio is increased. Conclusion. - Patients with McArdle disease show an exacerbation of cardiorespiratory, electromyographic and metabolic responses to exercise. A moderate aerobic training program induces muscle, cardiac and metabolic adaptations to physical strain and improves the tolerance of the patients to the physical exercise. [Copyright &y& Elsevier]

The brain serotonin (5-HT) system and circulating corticosteroids are in close interaction and both implicated in the pathogenesis of affective disorders. We evaluated the effects of adrenalectomy (ADX) on 5-HT1B receptors mRNA expression in cerebellum, frontal cortex, striatum and hippocampus in rats, using the RNase protection assay technique. Eight weeks after bilateral adrenalectomy, 5-HT1B receptor mRNA levels were decreased in the cerebellum and in the frontal cortex. The expression of 5-HT1B receptors mRNA was unchanged in the hippocampus and in the striatum. This data indicates regional differences in the effects of long term adrenalectomy on the expression of 5-HT1B receptors. [Copyright &y& Elsevier]

• Supramolecular polyurethanes with varied loadings of a low molecular weight bis-urea additive. • LMWAs cooperatively self-assemble with supramolecular polyurethanes. • LMWAs enhance the properties of the addressable and healable polymer networks. Low molecular weight additives which can cooperatively self-assemble with supramolecular polyurethanes via complementary hydrogen bonding interactions offer an attractive route to enhancing the properties of addressable polymer networks. Here, we present the design, synthesis, characterisation and mechanical properties of a series of supramolecular polyurethanes with varied loadings of a low molecular weight bis-urea additive. These additives are able to self-assemble with analogous recognition motifs within the supramolecular polyurethanes to form polar 'hard' domains, promoting phase separation within the material and, crucially, increasing the strength of the polymer network. In addition, the bis-urea additive is a by-product within the polymerisation and thus can be synthesised in situ , without the need for complex purification or blending. The mechanical properties of these reinforced polymers were enhanced when compared to the pristine supramolecular polyurethane alone, as a result of higher degrees of order within the polymer matrix. Furthermore, a formulation comprising the small molecule blended with the supramolecular polyurethane was produced to examine the effect of material preparation and filler dispersion within the polymer matrix. Interestingly, the mechanical performance of a blended material was diminished as a result of modest dispersion and incorporation within the polymer matrix. These findings thus demonstrate a facile, one-pot, method that does not require purification to produce reinforced supramolecular polyurethanes. This methodology may find use in industrial applications in which enhancements to the physical and mechanical properties can be easily achieved through the in situ synthesis of low molecular weight additives within the polymerisation. [ABSTRACT FROM AUTHOR]

Abstract: Heterozygous familial hypercholesteremia type II is a recessive autonomic disease with a population incidence ≤1:500. It develops as a consequence of a mutation in the LDLR gene. Patients suffer extremely high LDL and VLDL cholesterol values, dying from coronary compromise at early ages. As cholesterol synthesis is an hepatic process, and as there is a lack of gene therapy, hepatic transplantation is the only therapeutic option in cases refractory to medical treatment. In this report, we have described the first case of combined cardiohepatic transplantation in Argentina, which was performed in a male patient with severe aortic stenosis and terminal ischemic cardiopathy secondary to severe familial hypercholesteremia type II. [Copyright &y& Elsevier]

Abstract: Introduction: The Argentine Society of Transplants has set in motion an activity called Grand Rounds to Provide Feedback on Procurement Activities with the purpose of informing, training, and creating awareness by providing information about the evolution of transplanted patients. Objective: To measure, describe and analyze the impact that the transplant results presented at the rounds had on participants. Results: One hundred and fifty-eight surveys were conducted. The respondents'' average age was 40.06 years (95% confidence interval [CI 95%] 38.39–41.73) including 52.08% women (CI 95%: 43.92%–60.24%); 77.14% physicians (CI 95%: 84.09%–70.18%); 7.85% nurses (CI 95%: 3.4%–12.31%;) and 4.28% surgical nurses and other professional (CI 95%: 0.93%–7.64). When asked how comforted they felt when they learnt about a transplantation, the score prior to the round was 4 (CI 95%: 3.79–4.20) and after it, 4.8 (CI 95%: 4.69–4.90; P < .05). When asked about the transparency of the donation process, the average score before the round was 4.16 (CI 95%: 3.96–4.36) and after it, 4.76 (CI 95%: 4.67–4.86; P < .05). When asked how proactive they considered themselves before, before the average score was 3.54 (CI 95% 3.30–3.78) and post-round, 4.53 (CI 95%: 4.38–4.67; P < .05). When asked if they thought that this activity might be useful for them to manage future donors, 97.41% (CI 95%: 89%–96.98%) of respondents answered affirmatively. The answers to the question whether they thought this activity might increase donation were affirmative in 92.99% of cases; “Don''t know”, 6.36%; and negative in less than 1%. When consulted about their feelings, the preferred one was “happiness” for 46.82% of respondents; followed by “satisfaction” for 29.36% and “emotion” for 23.80%. The analysis of the open-ended questions revealed that the rounds were perceived as closure of the procurement-transplantation process. Conclusions: This widely accepted tool was viewed as a vehicle to interconnect links in the work process from organ procurement to transplantation. [Copyright &y& Elsevier]