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Tomato yellow leaf curl virus (TYLCV) is a begomovirus transmitted by the whitefly Bemisia tabaci to tomato and other crops. TYLCV proteins are endangered by the host defenses. We have analyzed the capacity of the tomato plant and of the whitefly insect vector to degrade the six proteins encoded by the TYLCV genome. Tomato and whitefly demonstrated the highest proteolytic activity in the fractions containing soluble proteins, less-in large protein aggregates; a significant decrease of TYLCV proteolysis was detected in the intermediate-sized aggregates. All the six TYLCV proteins were differently targeted by the cytoplasmic and nuclear degradation machineries (proteases, ubiquitin 26S proteasome, autophagy). TYLCV could confront host degradation by sheltering in small/midsized aggregates, where viral proteins are less exposed to proteolysis. Indeed, TYLCV proteins were localized in aggregates of various sizes in both host organisms. This is the first study comparing degradation machinery in plant and insect hosts targeting all TYLCV proteins., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Cultured tomatoes are often exposed to a combination of extreme heat and infection with Tomato yellow leaf curl virus (TYLCV). This stress combination leads to intense disease symptoms and yield losses. The response of TYLCV-susceptible and resistant tomatoes to heat stress together with viral infection was compared. The plant heat-stress response was undermined in TYLCV infected plants. The decline correlated with the down-regulation of heat shock transcription factors (HSFs) HSFA2 and HSFB1, and consequently, of HSF-regulated genes Hsp17, Apx1, Apx2 and Hsp90. We proposed that the weakened heat stress response was due to the decreased capacity of HSFA2 to translocate into the nuclei of infected cells. All the six TYLCV proteins were able to interact with tomato HSFA2 in vitro, moreover, coat protein developed complexes with HSFA2 in nuclei. Capturing of HSFA2 by viral proteins could suppress the transcriptional activation of heat stress response genes. Application of both heat and TYLCV stresses was accompanied by the development of intracellular large protein aggregates containing TYLCV proteins and DNA. The maintenance of cellular chaperones in the aggregated state, even after recovery from heat stress, prevents the circulation of free soluble chaperones, causing an additional decrease in stress response efficiency.

Background: There is a paucity of information regarding descriptive epidemiology of paediatric concussions over time, and few studies include both emergency department (ED) and physician office visits., Objective: To describe trends in visits for paediatric concussions in both EDs and physician offices according to age and sex. A secondary objective was to describe the cause of concussion for children treated in EDs., Methods: A retrospective, population-based study using linked health administrative data from all concussion-related visits to the ED or a physician office by school-age children and youth (three to 18 years of age) in Ontario between April 1, 2003 and March 3, 2011 was conducted., Results: The number of children evaluated in both EDs and a physician offices increased between 2003 and 2010, and this linear trend was statistically significant (P=0.002 for ED visits and P=0.001 for office visits). The rate per 100,000 increased from 466.7 to 754.3 for boys and from 208.6 to 440.7 for girls during the study period. Falls accounted for approximately one-third of the paediatric concussions. Hockey/skating was the most common specific cause of paediatric sports-related concussions., Conclusions: The increasing use of health care services for concussions is likely related to changes in incidence over time and increased awareness of concussion as a health issue. Evidence-based prevention initiatives to help reduce the incidence of concussion are warranted, particularly in sports and recreation programs.

Background: Although injuries related to sports and recreation represent a significant burden to children and youth, few studies have examined the descriptive epidemiology of sports-related injury since 2005, and some sports such as ringette have not been evaluated to date. The primary purpose of this study was to provide the descriptive epidemiology of sports-related injuries treated in emergency departments for children and youth aged 5 - 19., Methods: A retrospective data analysis was performed using data from the Canadian Hospitals Injury Reporting and Prevention Program [CHIRPP] from fiscal years (April - March) 2007/08 to 2009/10. CHIRPP is a computerized information system designed by the Public Health Agency of Canada that collects information about injuries to people evaluated in emergency departments across 11 pediatric hospitals and 5 general hospitals in Canada. Thirteen sports or activities were analyzed (baseball, basketball, cycling, football, ice hockey, lacrosse, ringette, rugby, skiing, sledding, snowboarding, soccer, and volleyball). Descriptive statistics, including frequency by sport, age and sex, as well as the percent of concussions within each sport were calculated., Results: Out of a total of 56, 691 reported sports and recreational injuries, soccer accounted for the largest proportion of injuries with 11,941 reported cases over the 3 year time period. Of these, approximately 30% were fractures. The 10 - 14 year age group reported the greatest proportion of injuries in 10 out of the 13 sports analyzed. In addition, males reported a greater number of overall injuries than females in 11 out of the 13 sports analyzed. The largest percentage of concussions was reported in ringette; these injuries accounted for 17.1% of overall injuries within this sport., Conclusions: Injury prevention programs in Canada should focus on improving evidence-based programs to reduce the burden of injuries in all sports.

Depth of anesthesia can be indirectly measured by Bispectral Index (BIS), therefore it is possible to administer propofol in a closed loop to maintain the optimal level of anesthesia while minimizing the dose to improve the postanesthesia recovery. High-Order Sliding-Mode control can be used to individualize drug dosing. In this study, the controller is tested with four in silico patients.

Theoretically High-Order Sliding-Mode Controllers are well suited to perform closed loop glucose regulation because they are insensitive to parameter uncertainties and robust to unknown dynamics that may perturb the system. The implementation of the controller based on the concept of practical relative degree is presented. The controller was tested in Sprague-Dawley rats with steptozotocin induced diabetes. The tests demonstrated high efficacy and robustness of the controller.

The success of blood glucose automatic regulation depends on the robustness of the control algorithm used. It is a difficult task to perform due to the complexity of the glucose-insulin regulation system. The variety of model existing reflects the great amount of phenomena involved in the process, and the inter-patient variability of the parameters represent another challenge. In this research a High-Order Sliding-Mode Control is proposed. It is applied to two well known models, Bergman Minimal Model, and Sorensen Model, to test its robustness with respect to uncertain dynamics, and patients' parameter variability. The controller designed based on the simulations is tested with the specific Bergman Minimal Model of a diabetic patient whose parameters were identified from an in vivo assay. To minimize the insulin infusion rate, and avoid the hypoglycemia risk, the glucose target is a dynamical profile.

A single administration of an extremely low dose (0.002 mg/kg) of Delta9-tetrahydrocannabinol (THC; the psychoactive ingredient of marijuana) to ICR mice induced long-term cognitive deficits that lasted for at least 5 months. The behavioral deficits were detected by several tests that evaluated different aspects of memory and learning, including spatial navigation and spatial and non-spatial recognition. Our findings point to possible deficits in attention or motivation that represent a common upstream cognitive process that may affect the performance of the mice in the different behavioral assays. Similar ultra-low doses of THC (3-4 orders of magnitude lower than doses that are known to evoke the acute effects of THC) also induced sustained activation of extracellular-regulated kinase (ERK1/2) in the cerebellum, indicating that a single injection of such low doses of the cannabinoid drug can stimulate neuronal regulatory mechanisms. The relevance of these findings to the behavioral consequences of chronic exposure to marijuana is discussed.

Beta-endorphin is an endogenous opioid peptide, implicated in the behavioral effects of drugs of abuse. It is synthesized in the arcuate nucleus and secreted into the nucleus accumbens. In the present study, we examined the interaction between arcuate nucleus dopaminergic cells and accumbal beta-endorphin, during cocaine exposure. Using microdialysis, we found that blockade of arcuate dopamine-2 receptors with a selective antagonist significantly attenuated cocaine-induced increases of beta-endorphin levels in the nucleus accumbens. Moreover, rats chronically exposed to cocaine using the self-administration paradigm displayed extinction-like behavior following blockade of dopamine-2 receptors. These findings indicate that dopaminergic neurons in the arcuate nucleus may induce the secretion of beta-endorphin in the nucleus accumbens, and that they are implicated in the cocaine reward pathway.

Dehydroepiandrosterone (DHEA), which can act as a potential antidepressant in both animals and humans, appears to lower distress involved with cocaine withdrawal. In fact, a role for neurosteroids in modulation of substance-seeking behavior is becoming increasingly clear. Therefore, we tested the effects of DHEA on the self-administration of cocaine (1 mg/kg/infusion) by rats. At maintenance, a relatively low dose of exogenous DHEA (2 mg/kg; i.p.) attenuated cocaine self-administration after several days of chronic treatment. More than 2 weeks (19 days) of daily DHEA injections were required to decrease the cocaine-seeking behavior of rats to less than 20% of their maintenance levels. DHEA does not seem to decrease cocaine self-administration by increasing the reinforcing properties of the drug, as indicated by a cocaine dose-response determination. After being subjected to extinction conditions in the presence of DHEA, rats demonstrated a minimal response to acute exposure to cocaine (10 mg/kg), which indicated a protective effect of DHEA on relapse to cocaine usage. Our results suggest a potential role for the neurosteroid DHEA in controlling cocaine-seeking behavior, by reducing both the desire for cocaine usage and the incidence of relapse.

The differential diagnosis between intra- and extrahepatic causes of jaundice was studied. At the "20 Noviembre" ISSSTE Hospital in Mexico City, between January 1977 and May 1984, data were collected in 1,263 jaundiced patients. To the clinical data for 1,000 of these 1,263 patients and a new set of 105 jaundiced patients, the COMIC study group algorithm was applied. The differential diagnosis between medical and surgical causes of jaundice was correct in 90% of the cases. In 85% the algorithm could also differentiate between acute and chronic disease, or between benign and malignant causes of jaundice. The COMIC algorithm was then modified and applied to the same 1,000 cases examined previously, with 96% accuracy in distinguishing medical and surgical causes of jaundice and 94% accuracy in discriminating between acute and chronic, or benign and malignant, disease. In a new set of 105 cases of jaundiced patients the modified COMIC algorithm made the correct diagnosis between intra- and extrahepatic causes for 98% of the patients, and for 93% it was also capable of distinguishing benign from malignant and acute from chronic causes of jaundice.