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21.
Matthieu Heidet Abdel Abdel Wahab Vahid Ebadi Yann Cogne Charlotte Chollet-Xemard Mehdi Khellaf 《The Journal of emergency medicine》2019,56(3):279-281
Background
Bodybuilding is a demanding sport, which requires high-volume, high-resistance weight training and augmented nutritional intake, toward an increase of overall body muscle mass accompanied by an overall decrease of body fat percentage and mass. Among bodybuilders, the use of various legal and illegal supplements is common. These supplements may be naturally occurring or man-made.Case Report
We discuss the case of a 30-year-old male bodybuilder presenting with coma due to severe hypoglycemia from unknown cause, necessitating iterative glucose infusions, which was subsequently found to be related to cryptic insulin injections.Why Should an Emergency Physician Be Aware of This?
In strength athletes, especially amateurs, the recourse to performance-enhancement drugs (e.g., insulin) is frequent. Beyond the specificity of care required for surreptitious insulin intoxication, emergency physicians should be alert to the possibility that exogenous insulin has been injected for use as an ergogenic aid by bodybuilders and others seeking to increase their body muscle mass when they encounter a patient with a decreased level of consciousness and treatment-refractory hypoglycemia. Moreover, in case of suspicion of such intoxication, the use of other illegal supplements should be screened, due to potentially associated risks of complication. 相似文献22.
Outcomes of regenerative treatment with rhPDGF‐BB and rhFGF‐2 for periodontal intra‐bony defects: a systematic review and meta‐analysis 下载免费PDF全文
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Erythropoietin attenuates motor impairments induced by bilateral renal ischemia/reperfusion in rats 下载免费PDF全文
Mahshid Tahamtan Seyed M.S. Moosavi Vahid Sheibani Mohsen Nayebpour Saeed Esmaeili‐Mahani Mohammad Shabani 《Fundamental & clinical pharmacology》2016,30(6):502-510
Neurologic sequelae remain a common and destructive problem in patients with acute kidney injury. The objective of this study was to evaluate the possible neuroprotective effect of erythropoietin (EPO) on motor impairments following bilateral renal ischemia (BRI) in two time points after reperfusion: short term (24 h) and long term (1 week). Male Wistar rats underwent BRI or sham surgery. EPO or saline administration was performed 30 min before surgery (1000 U/kg, i.p.). Explorative behaviors and motor function of the rats were evaluated by open field, rotarod, and wire grip tests. Plasma concentrations of blood urea nitrogen (BUN) and creatinine (Cr) were significantly enhanced in BRI rats 24 h after reperfusion. BRI group had only an increased level of BUN but not Cr 1 week after reperfusion. Impairment of balance function by BRI was not reversed by EPO 24 h after reperfusion, but counteracted 7 days after renal ischemia. Muscle strength had no significant differences between the groups. BRI group had a decrease in locomotor activity, and EPO could not reverse this reduction in both time points of the experiment. Although EPO could not be offered as a potential neuroprotective agent in the treatment of motor dysfunctions induced by BRI, it could be effective against balance dysfunction 1 week after renal ischemia. 相似文献
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Cellular expression of CD markers in immune thrombocytopenic purpura: implications for prognosis 下载免费PDF全文
Masumeh Maleki Behzad Ali Amin Asnafi Mohammad Ali Jalalifar Mostafa Moghtadaei Kaveh Jaseb Najmaldin Saki 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2018,126(6):523-532
Immune thrombocytopenic purpura (ITP) is an autoimmune bleeding disorder associated with platelet destruction. Abnormalities in frequency and function of different immune cells can play a crucial role in this disease. The aim of this study was to evaluate the prognostic value of CD markers’ expressions by immune cells in ITP. Peripheral blood samples were collected from 25 ITP patients before and after treatment. The expression of CD markers was evaluated by flow cytometry technique. The expression of CD38 and CD56 was significantly lower before treatment than after it (p = 0.025 and p = 0.036, respectively). Furthermore, a positive correlation was found between CD38 expression with platelet count before (r = 0.496, p = 0.012) and after treatment (r = 0.404, p = 0.045). No significant relationship was found between this marker and platelet count while CD4 expression was higher before treatment than after it (p = 0.002). In conclusion, CD38 may have independent prognostic value in ITP and we suggest that it can be a prognostic marker for this disease. 相似文献
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Vahid Mehrpour Travis Meyer Eero P. Simoncelli Nicole C. Rust 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(18)
Memories of the images that we have seen are thought to be reflected in the reduction of neural responses in high-level visual areas such as inferotemporal (IT) cortex, a phenomenon known as repetition suppression (RS). We challenged this hypothesis with a task that required rhesus monkeys to report whether images were novel or repeated while ignoring variations in contrast, a stimulus attribute that is also known to modulate the overall IT response. The monkeys’ behavior was largely contrast invariant, contrary to the predictions of an RS-inspired decoder, which could not distinguish responses to images that are repeated from those that are of lower contrast. However, the monkeys’ behavioral patterns were well predicted by a linearly decodable variant in which the total spike count was corrected for contrast modulation. These results suggest that the IT neural activity pattern that best aligns with single-exposure visual recognition memory behavior is not RS but rather sensory referenced suppression: reductions in IT population response magnitude, corrected for sensory modulation.Under the right conditions, we are very good at remembering the images that we have seen: we can remember thousands of images after viewing each only once and only for a few seconds (1, 2). How our brains support this remarkable ability, often called “visual recognition memory” (3), is not well understood. The most prominent proposal to date suggests that memories about whether images have been encountered before are signaled in high-level visual brain areas such as inferotemporal cortex (IT) and perirhinal cortex via adaptation-like reductions of the population response to repeated as compared to novel stimuli, a phenomenon referred to as repetition suppression (RS) (4–9). Repetition suppression exhibits the primary attributes needed to account for the vast capacity of single-exposure visual memory behavior: response decrements in subsequent exposures are selective for image identity (even after viewing an extensive sequence of other images), and last for several minutes to hours (5, 6, 10). RS has also been shown to account for behavior in an image recognition memory task: a linear decoder with positive weights can predict single-exposure visual recognition memory behavior from neural responses in IT cortex (10).Despite the fact that the RS hypothesis is consistent with available evidence, it seems likely to be too simplistic an explanation for visual recognition memory encoding. In particular, it is well known that sensory neurons such as those of IT cortex are modulated not only by image memory, but also by stimulus properties such as image contrast (11). It is thus unclear whether and how these stimulus-induced effects interfere with judgments of whether images are novel or have been encountered before, and if they do not, how image memory can be decoded from neural responses in a way that disambiguates it from changes in these stimulus properties. To investigate this, we measured behavioral and neural responses of monkeys trained to report whether images were novel or repeated while disregarding image contrast (Fig. 1A).Open in a separate windowFig. 1.Visual memory behavior. (A) The contrast-invariant, single-exposure visual memory task. The monkeys viewed a sequence of images and reported whether they were novel (never seen before) or repeated (seen exactly once) while ignoring randomized changes in contrast. Monkeys were trained to saccade to one of two response targets to indicate their choice (red arrows). Images were repeated with a randomly chosen delay between the first and repeated presentation (“n-back”). (B) Images were displayed at one of two contrast levels, yielding two conditions for novel images, high (H) and low (L), and four conditions for repeated images: HH (repeated H preceded by novel H), LL (repeated L preceded by novel L), HL (repeated L preceded by novel H), and LH (repeated H preceded by novel L). The four repeated conditions were organized into same-contrast and mixed-contrast groups depending on whether the initial and repeated presentations were at the same or different contrasts, respectively. (C) Behavioral performance for the data pooled across monkeys in the task, where small black dots indicate average performance for an individual session and large colored dots indicate the average performance across sessions. A measure of contrast invariance, I, was computed as the ratio of the variance across contrast conditions and the variance with respect to the maximally contrast-modulated pattern after taking overall performance into account, subtracted from 1 (SI Appendix, SI Methods). Insets illustrate the expected behavioral pattern with minimal (I = 0) and maximal (I = 1) contrast invariance. 相似文献
30.
Somayeh Shahani Mostafa Rostamnezhad Vahid Ghaffari-rad Arash Ghasemi Tayyeb Allahverdi Pourfallah Seyed Jalal Hosseinimehr 《Dose-response》2015,13(1)
The radioprotective effect of Achillea millefolium L (ACM) extract was investigated against genotoxicity induced by ionizing radiation (IR) in human lymphocytes. Peripheral blood samples were collected from human volunteers and incubated with the methanolic extract of ACM at different concentrations (10, 50, 100, and 200 μg/mL) for 2 hours. At each dose point, the whole blood was exposed in vitro to 2.5 Gy of X-ray and then the lymphocytes were cultured with mitogenic stimulation to determine the micronuclei in cytokinesis-blocked binucleated cell. Antioxidant capacity of the extract was determined using free radical-scavenging method. The treatment of lymphocytes with the extract showed a significant decrease in the incidence of micronuclei binucleated cells, as compared with similarly irradiated lymphocytes without any extract treatment. The maximum protection and decrease in frequency of micronuclei were observed at 200 μg/mL of ACM extract which completely protected genotoxicity induced by IR in human lymphocytes. Achillea millefolium extract exhibited concentration-dependent radical-scavenging activity on 1,1-diphenyl-2-picryl hydrazyl free radicals. These data suggest that the methanolic extract of ACM may play an important role in the protection of normal tissues against genetic damage induced by IR. 相似文献