Functionally Graded Al2O3–CTZ Ceramics Fabricated by Spark Plasma Sintering

We studied the fabrication of functionally graded Al₂O₃–CeO₂-stabilized-ZrO₂ (CTZ) ceramics by spark plasma sintering. The ceramic composite exhibits a gradual change in terms of composition and porosity in the axial direction. The composition gradient was created by layering starting powders with different Al₂O₃ to CTZ ratios, whereas the porosity gradient was established with a large temperature difference, which was induced by an asymmetric graphite tool configuration during sintering. SEM investigations confirmed the development of a porosity gradient from the top toward the bottom side of the Al₂O₃–CTZ ceramic and the relative pore volume distributed in a wide range from 0.02 to 100 µm for the samples sintered in asymmetric configuration (ASY), while for the reference samples (STD), the size of pores was limited in the nanometer scale. The microhardness test exhibited a gradual change along the axis of the ASY samples, reaching 10 GPa difference between the two opposite sides of the Al₂O₃–CTZ ceramics without any sign of delamination or cracks between the layers. The flexural strength of the samples for both series showed an increasing tendency with higher sintering temperatures. However, the ASY samples achieved higher strength due to their lower total porosity and the newly formed elongated CeAl₁₁O₁₈ particles.     

New serological markers in pediatric patients with inflammatory bowel disease

The spectrum of serological markers associated with inflammatory bowel disease(IBD)is rapidly growing.Due to frequently delayed or missed diagnoses,the application of non-invasive diagnostic tests for IBD,as well as differentiation between ulcerative colitis(UC)and Crohn’s disease(CD),would be useful in the pediatric population.In addition,the combination of pancreatic autoantibodies and antibodies against Saccharomyces cerevisiae antibodies/perinuclear cytoplasmic antibody(pANCA)improved the sensitivity of serological markers in pediatric patients with CD and UC.Some studies suggested that age-associated differences in the patterns of antibodies may be present,particularly in the youngest children.In CD,most patients develop stricturing or perforating complications,and a significant numberof patients undergo surgery during the disease course.Based on recent knowledge,serum antibodies are qualitatively and quantitatively associated with complicated CD behavior and CD-related surgery.Pediatric UC is characterized by extensive colitis and a high rate of colectomy.In patients with UC,high levels of antiCBir1 and pANCA are associated with the development of pouchitis after ileal pouch-anal anastomosis.Thus,serologic markers for IBD can be applied to stratify IBD patients into more homogeneous subgroups with respect to disease progression.In conclusion,identification of patients at an increased risk of rapid disease progression is of great interest,as the application of early and more aggressive pharmaceutical intervention could have the potential to alter the natural history of IBD,and reduce complications and hospitalizations.     

Narcolepsy and pregnancy: a retrospective European evaluation of 249 pregnancies

In a retrospective cohort study undertaken in 12 European countries, 249 female narcoleptic patients with cataplexy (n = 216) and without cataplexy (n = 33) completed a self‐administrated questionnaire regarding pregnancy and childbirth. The cohort was divided further into patients whose symptoms of narcolepsy started before or during pregnancy (308 pregnancies) and those in whom the first symptoms of narcolepsy appeared after delivery (106 pregnancies). Patients with narcolepsy during pregnancy were older during their first pregnancy (P < 0.001) and had a higher body mass index (BMI) prior to pregnancy (P < 0.01). Weight gain during pregnancy was higher in narcoleptic patients with cataplexy (P < 0.01). More patients with narcolepsy–cataplexy during pregnancy had impaired glucose metabolism and anaemia. Three patients experienced cataplexy during delivery. The rate of caesarean sections was higher in the narcolepsy–cataplexy group compared to the narcolepsy group (P < 0.05). The mean birth weight and gestational age of neonates were within the normal range and did not differ across groups. Neonatal care was affected adversely by symptoms of narcolepsy in 60.1% of those with narcolepsy during pregnancy. This study reports more obstetric complications in patients with narcolepsy–cataplexy during pregnancy; however, these were not severe. This group also had a higher BMI and higher incidence of impaired glucose metabolism during pregnancy. Caesarian section was conducted more frequently in narcolepsy–cataplexy patients, despite cataplexy being a rare event during delivery. Furthermore, symptoms of narcolepsy may render care of the infant more difficult.     

Contribution of I Ks to ventricular repolarization in canine myocytes

The role of the slow delayed rectifier K⁺ current (I _Ks) in cardiac repolarization seems to be largely influenced by the experimental conditions including the species and tissue studied. The aim of this study was to determine the contribution of I _Ks to repolarization in canine ventricular myocytes by measuring the frequency dependent action potential lengthening effect of 10 μM chromanol 293B using sharp microelectrodes. Pretreatment with isoproterenol (2 nM), E-4031 (1 μM), and injection of inward current pulses were applied to modify action potential configuration. Chromanol alone caused moderate but statistically significant lengthening of action potentials at cycle lengths longer than 500 ms. The lengthening effect of chromanol, which was strongly enhanced in the presence of either isoproterenol or E-4031, was proportional to the amplitude of plateau, whereas poor correlation was found with action potential duration. Similar results were obtained when action potential configuration was modified by injection of depolarizing current pulses. Computer simulations revealed that activation of I _Ks is a sharp function of the plateau amplitude within the physiological range, while elongation of repolarization may enhance I _Ks only when it is excessive. It was concluded that the effect of I _Ks on ventricular repolarization critically depends on the level of action potential plateau; however, other factors, like action potential duration, cycle length, or suppression of other K⁺ currents can also influence its contribution.     

Different patterns of morphological changes in the hippocampus and dentate gyrus accompany the differential expression of disability following nerve injury

Physical and psychological trauma which results in mood disorders and the disruption of complex behaviours is associated with reductions in hippocampal volume. Clinical evaluation of neuropathic pain reveals mood and behavioural change in a significant number of patients. A rat model of neuropathic injury results in complex behavioural changes in a subpopulation (~30%) of injured rats; these changes are co‐morbid with a range of other ‘disabilities’. The specific objective of this study was to determine in rats the morphology of the hippocampus and dentate gyrus in individuals with and without complex behavioural disruptions following a constriction injury of the sciatic nerve, and to determine whether rats that develop disabilities following nerve injury have a reduced hippocampal volume compared with injured rats with no disabilities. The social behaviours of nerve‐injured rats were evaluated before and after nerve injury. The morphology of the hippocampus of rats with and without behavioural disruptions was compared in serial histological sections. Single‐housing and repeated social‐interaction testing had no effect on the morphology of either the hippocampus or the dentate gyrus. Rats with transient or ongoing disability identified by behavioural disruption following sciatic nerve injury, show bilateral reductions in hippocampal volume, and lateralised reduction in the dentate gyrus (left side). Disabled rats display a combination of behavioural and physiological changes, which resemble many of the criteria used clinically to diagnose mood disorders. They also show reductions in the volume of the hippocampus similar to people with clinically diagnosed mood disorders. The sciatic nerve injury model reveals a similarity to the human neuropathic pain presentation presenting an anatomically specific focus for the investigation of the neural mechanisms underpinning the co‐morbidity of chronic pain and mood disorder.     

The Impact of the Universal Infant Free School Meal Policy on Dietary Quality in English and Scottish Primary School Children: Evaluation of a Natural Experiment

The Universal Infant Free School Meal (UIFSM) policy was introduced in September 2014 in England and January 2015 in Scotland and offered all infant schoolchildren (ages 4–7 years) a free school lunch, regardless of income. Yet, impacts of UIFSM on dietary intakes or social inequalities are not known. A difference-in-differences study using the National Diet and Nutrition Survey assessed pooled pre-UIFSM (2010–2014) and post-UIFSM (2014–2017) dietary data. English or Scottish infant schoolchildren (4–7 years; n = 458) were the intervention group, with junior schoolchildren (8–11 years; n = 401) as controls. We found that implementation of UIFSM led to an increase in infant schoolchildren having a school meal. Impacts on key food groups such as fruit and vegetables or sweetened beverages were not seen. However, there was evidence that the UIFSM policy lowered consumption of foods associated with packed lunches, such as crisps, and some nutrients, such as total fat and sodium. Policy impacts differed by income group, with larger effect sizes in low-income children. In conclusion, evaluation of UIFSM demonstrated some improvements in dietary quality but the findings suggest school meal quality needs to be improved to fully realise the benefits of UIFSM.