Entrainment by a palatable meal induces food-anticipatory activity and c-Fos expression in reward-related areas of the brain

Rats maintained under restricted feeding schedules (RFS) develop food-anticipatory activity and entrainment of physiological parameters. Food entrainment is independent of the suprachiasmatic nucleus and depends on food-entrainable oscillators (FEO). Restricted feeding schedules lead animals toward a catabolic state and to increase their food driven motivation, suggesting that in this process metabolic- and reward-related mechanisms are implicated. This study explored if motivation driven by a palatable meal is sufficient to produce food-entrainment. To address this question, we evaluated whether daily fixed access to a highly palatable meal entrained (PME) locomotor activity, serum glucose and free fatty acids concentrations in rats maintained without food deprivation. The entrained response of PME rats was compared with rats entrained to RFS. In a second experiment, we used c-Fos-IR to identify structures in the central nervous system involved with PME. Rats showed anticipatory activity to a daily palatable meal, with a lower intensity than rats entrained to RFS. Anticipatory activity persisted at least for four cycles after interrupting palatable meal, suggesting that this persistence depends on an endogenous oscillator. Glucose and free fatty acids were not entrained in PME rats. c-Fos expression in limbic system nuclei was in phase with PME time, but not in the hypothalamus. Results suggest 1) that food deprivation, i.e. a catabolic state is not necessary for the expression of anticipatory activity; 2) that an increase in the motivational state due to taste and/or nutritional contents of palatable meal is sufficient to entrain behavior; and 3) that structures in the limbic system are involved in this entrainment process. The present study indicates that metabolic and motivational mechanisms are involved in food entrainment, and suggests that the FEO may be a multi-oscillatory system distributed over different regulatory systems in the brain.     

Checkpoint Blockade Immunotherapy Induces Dynamic Changes in PD-1−CD8+ Tumor-Infiltrating T Cells

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Cross-cultural aspects of the somatization trait

Studies using a variety of diagnostic rating scales have identified much higher levels of somatic symptoms in Hispanic psychiatric patients, particularly those with a diagnosis of schizophrenia or depression, than in their Anglo counterparts. However, this cultural difference cannot be generally demonstrated by using DSM-III somatoform disorders criteria. Many patients with "unfounded" somatic symptoms have another DSM-III primary diagnosis that is often assumed to cause or explain the somatic symptoms. In addition, the true prevalence of unfounded somatic symptoms is hidden because of the strict criteria required for a DSM-III primary diagnosis of somatization disorder. The author believes a more inclusive notion of somatization should be developed that would substantiate the presence of this trait among different populations and, if operationalized, would facilitate research on this important phenomenon. This is relevant not only because of the cross-cultural variability of somatization traits but also because they may become a salient feature of the primary syndrome and determine the use of clinical services. He proposes a new operational definition of somatization that encompasses the trait concept.     

Septicaemia caused by Klebsiella pneumoniae--a review of 28 cases

Twenty-eight children with septicaemia and positive blood cultures for Klebsiella pneumoniae were retrospectively studied and compared with 190 children with sepsis caused by other organisms, identified or not in blood cultures. Septicaemia due to Klebsiella pneumoniae occurred more frequently in children older than 2 years of age, especially those who had an underlying disease and, therefore, were malnourished or had an impaired immune defense system that had required invasive procedures and previous hospitalization. Although the case fatality rate was high in both groups, Klebsiella pneumoniae did not contribute to elevate the relative risk of death. In this study, Klebsiella pneumoniae isolates were highly sensitive to colistin (92.9%) and cefoxitin (82.1%), but poorly sensitive to third generation cephalosporin and imipenen.     

Humanistic and social education for physicians: the experience of the Colombian School of Medicine

Medical education at the Colombian School of Medicine has undergone a reconceptualization and reorganization so as to encompasses three fundamental elements of medical practice: 1) development of general abilities and standards necessarky for appropriate professional medical practice; 2) technical education which makes it possible to utilize the bases that science and technology have provided for the development and application of knowledge, and in turn, to expand this base through research and development; and 3) humanistic education to guide students into ethical professional practice.     

Cardiovascular Response and Anesthetic Recovery in Electroconvulsive Therapy with Propofol or Thiopental

Propofol provokes a slight hypotensive effect that could mitigate the cardiovascular response to electroconvulsive therapy (ECT). In this study we compared the effects of propofol and thiopental for ECT anesthesia in seven women (22-67 years of age). Anesthesia was induced with either thiopental or propofol, and with atropine and suxamethonium for each treatment. The first anesthesia was assigned to thiopental or propofol at random; the next anesthesia was induced with the other drug, and alternated thereafter. Systolic blood pressure, diastolic blood pressure (DBP), and heart rate (HR) were recorded before anesthesia, after anesthetic induction, and 1 and 5 min after ECT. ECT-induced increases in DBP and HR were less marked with propofol than with thiopental. Seizure durations were decreased with propofol compared with thiopental.