Respiratory effects of extradural analgesia after lower abdominal surgery

Blood-gas tensions, FRC and volume of trapped gas (VTG) in the lung were measured in patients on the day before lower abdominal gynaecological surgery, and twice on the day following surgery, before and after establishing lumbar extradural block (EDB) using 0.5% bupivacaine to provide analgesia after operation. FRC and VTG were measured with the closed-circuit helium-dilution technique. Mean VTG was 175 ml before operation and 275 ml after operation. PaO2 decreased significantly after operation, and the changes in FRC and VTG that occurred were related qualitatively. EDB did not significantly alter FRC, VTG or PaO2. Individual changes in FRC could not be related to changes in VTG or PaO2. Although EDB provided effective analgesia, the variables measured did not indicate that EDB conferred an immediate respiratory advantage.     

Sudden incapacitation: USAF experience, 1970-80

During the period 1970-80, there were reported 146 cases of in-flight sudden incapacitation in the USAF. Of these, 62 involved pilots, 14 were navigators, and 70 were student pilots. The etiologies of sudden incapacitation included illness without loss of consciousness, loss of consciousness, spatial disorientation, and improper M-1 maneuver. Each of these categories is analyzed with emphasis upon prevention, for example, not flying with symptomatic preexisting disease, continued emphasis upon spatial disorientation training, and correct performance of the M-1 maneuver. Based upon the data, conclusions and recommendations are suggested to minimize the risk of episodes of in-flight sudden incapacitation.     

Simultaneous dual-task performance reveals parallel response selection after practice.

E. H. Schumacher, T. L. Seymour, J. A Glass, D. E. Kieras, and D. E. Meyer (2001) reported that dual-task costs are minimal when participants are practiced and give the 2 tasks equal emphasis. The present research examined whether such findings are compatible with the operation of an efficient response selection bottleneck. Participants trained until they were able to perform both tasks simultaneously without interference. Novel stimulus pairs produced no reaction time costs, arguing against the development of compound stimulus-response associations (Experiment 1). Manipulating the relative onsets (Experiments 2 and 4) and durations (Experiments 3 and 4) of response selection processes did not lead to dual-task costs. The results indicate that the 2 tasks did not share a bottleneck after practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Identification of beta-L-gulose as the sugar moiety of the main polar lipid Thermoplasma acidophilum

We studied the antibody binding capacity (ABC) of various cell-surface antigens in normal human fetuses and term neonates on lymphocyte, monocyte, and polymorphonuclear (PMN) cells by quantitative flow cytometry also designated by quantimetry. Analysis of changes of expression level on these leukocytes during the developmental process was also investigated. The results indicated that the ABC values of most studied markers change during the maturational process. The ABC of lymphocyte-associated antigens studied such as CD5 and CD7 showed only a decrease from fetus to adult, whereas according to the type of molecule on monocyte and PMN there was either an increase or a decrease of ABC values dependent on the stage of the developmental process, from fetus to neonate or from neonate to adult. However, the ABC values of leukocyte membrane antigens such as CD16, CD46, and CD55 on all leukocytes and CD11b, CD11c, and CD35 on myeloid cells did not change. Their expression level was already mature in fetuses compared with adult cells. In addition, in this quantimetric approach, the analysis of the results for CD11a and CD8 suggested that the changes of CD11a expression level on lymphocyte subsets can depend on one mechanism, whereas there are probably at least two for CD8. Furthermore, the expression patterns of CD5, CD7, and CD11a change during maturation. We concluded that, even if the neonate response pattern to immunological challenge differs from an adult and this is based primarily on the relative numbers and functional activity of lymphocyte T subsets (especially TH1/TH2) and their cytokine profiles, these quantitative and qualitative phenotypical differences might also contribute to explain the functional peculiarities of leukocyte fetal and cord blood cells. All these findings support the notion of immaturity and maturity of ABC expression.     

Tuft-to-capsule adhesions and their precursors: differences between the vascular and tubular poles of the human glomerulus

The hypothalamo-pituitary-adrenal (HPA) axis is modulated by sex hormones. Few data exist on the relation between acute estrogen deficit and HPA axis response to corticotropin-releasing hormone (CRH). The effects of a sudden drop in estradiol levels on basal and CRH-stimulated levels of ACTH, cortisol, testosterone, androstenedione and 17-hydroxyprogesterone (17-OHP) were assessed in nine premenopausal women (44-48 years of age), before and after ovariectomy. The CRH test was performed before and 8 days after ovariectomy. A significant reduction in ACTH and adrenal steroids but not in cortisol response to CRH was observed after ovariectomy. The ratio of deltamax androstenedione/17-OHP after CRH stimulation was substantially the same before and after ovariectomy, whereas deltamax 17-OHP/cortisol was significantly lower in ovariectomized women showing increased 21- and 11beta-hydroxylase activity. The results show that the acute estrogen deficit induces changes in the HPA axis characterized by reduced stimulated secretion of ACTH and steroids but normal stimulated cortisol production.