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991.
5-Hydroxytryptamine (5-HT) activates the extracellular signal-regulated kinase (Erk) mitogen-activated protein kinases (MAPKs) in the vasculature, resulting in contraction. The mechanisms by which this occurs are unclear. G protein-coupled receptors can activate Erk MAPK pathways through a variety of mechanisms, including stimulation of Src, phosphoinositide-3 kinase (PI-3-K), protein kinase C (PKC), or the epidermal growth factor (EGF) receptor tyrosine kinase. We hypothesize that 5-HT uses one or more of these pathways. In isolated strips of rat aorta, the MAPK/Erk kinase inhibitor U0126 (50 microM), Src inhibitor PP1 (0.5 microM), PKC inhibitors calphostin C (1 microM) and chelerythrine (10 microM), and the PI-3-K inhibitor LY294002 (1-20 microM) reduced 5-HT-induced contraction. The EGF receptor tyrosine kinase inhibitor AG1478 (0.25-1 microM) was without effect. Thus, 5-HT activates PKC, Src, and possibly PI-3-K to result in contraction. In rat aortic myocytes, 5-HT (1 microM) activated Erk MAPK proteins 2- to 3-fold over basal values; activation was reduced by U0126, PP1, and LY294002 and unaffected by calphostin C or chelerythrine, wortmannin, or AG1478. The lack of effect of EGF receptor tyrosine kinase and PI-3-K inhibitors was confirmed in that the EGF receptor immunoprecipitated from 5-HT-exposed cells did not display an increase in autophosphorylation, nor did 5-HT significantly increase activation of Akt/protein kinase B, a downstream substrate for PI-3-K. These data suggest that the rat aortic 5-HT(2A) receptor uses Src but not PKC, PI-3-K, or the EGF receptor tyrosine kinase in stimulating Erk MAPK activation.  相似文献   
992.
In 2016, the workflow for MRSA detection in nasal swabs was changed from a classic-manual workflow to an automated workflow using total lab automation (TLA; BD Kiestra). This change entailed a reduction of the incubation time from 2 days to 20 h and reading of plates on weekdays and weekends instead of weekdays only. The workflow alteration did not include the introduction of 24/7. We wanted to follow up on the consequences for the times to report (TTR). We compared the TTR of all nasal swabs, which were sent for MRSA detection from June until August in 2015 (workflow—classic-manual) and in 2016 (workflow—automated). We calculated median TTR and interquartile ranges for the three possible reporting outcomes (negative, MRSA-known, MRSA-new) per day and workflow. A multivariable linear regression modeled the exposure variables workflow, day, and reporting outcome on TTR including interaction variables. The quantity and reasons for a TTR longer than 3 days were analyzed. During both 3-month periods, a total of 16,111 reports were issued (2015:7620; 2016:8491). The median TTR for negative reports was 48:28 (hh:mm) in 2015 and 23:58 in 2016. In the linear regression, all exposure variables had a strong and highly significant (p?<?0.001) influence on the TTR. The number of reports with a TTR longer than 3 days shrank from 2418 (2015) to 60 (2016). The workflow alteration halved the median TTR for negative reports and the number of reports with a TTR longer than 3 days was reduced by 97.5%.  相似文献   
993.
994.
Hemicrania continua (HC) is a primary chronic headache disorder, characterized by a continuous and strictly unilateral headache, with possible cranial autonomic symptoms during episodes of pain exacerbation. The unilateral headache generally responds well to indomethacin; however, continuous indomethacin intake is often not tolerated due to severe adverse effects, like hypertension, gastrointestinal discomfort (especially if combined with aspirin), slightly increased risk of vascular events, and bronchial spasms. Therefore, alternative treatment options are desperately needed. Non‐invasive vagus nerve stimulation (nVNS) has been shown to be effective in patients with cluster headache, another trigeminal autonomic cephalalgia (TAC), with cranial parasympathetic autonomic activation during the attacks.  相似文献   
995.
Severe blunt chest trauma is frequently associated with multiple organ failure and sepsis. Posttraumatic immunosuppression seems to play a major role in their development. However, the immunologic alterations following pulmonary contusion are insufficiently elucidated. Specifically, it remains unknown whether immunocompetent cells located distant from the site of the impact are affected. We therefore aimed to characterize the influence of pulmonary contusion on lymphocytes and splenic macrophages. Male C3H/HeN mice (n = 8-10/group) were anesthetized and subjected to trauma or sham procedure. Blunt chest trauma was induced by a blast wave focused on the thorax. Two or 24 h later, splenocytes and splenic macrophages were isolated and stimulated for 48 h. The cytokine release (IFN-gamma, IL-2, IL-3, IL-10, IL-12, IL-18) from splenocytes as well as from splenic macrophages (TNF-alpha, IL-10, IL-12, IL-18) and plasma levels of TNF-alpha and IL-6 were quantified by ELISA. The results indicate that at 2 h after blunt chest trauma, plasma TNF-alpha and IL-6 were markedly increased. At the same time, no differences in splenocyte cytokine production were detectable. However, at 24 h a significantly depressed cytokine release was observed in trauma animals. Furthermore, splenic macrophages showed a significantly decreased production of TNF-alpha, IL-10, and IL-12 at 24 h and markedly increased release of IL-18 at 2 h after trauma. These results indicate that blunt chest trauma causes severe immunodysfunction of lymphocytes and splenic macrophages. Thus, lung contusion as a localized type of trauma causes dysfunction of immunocompetent cell populations, which are located distant from the site of injury.  相似文献   
996.
Chronic nausea occurs in most patients with advanced cancer. This study was done to assess the antiemetic effects of dexamethasone in patients with chronic nausea refractory to metoclopramide. Secondary outcomes included appetite, fatigue, and pain. Fifty-one patients who had nausea (> or = 3/10 on a 0-10 scale) for > or = 2 weeks despite 48 hours of oral metoclopramide therapy (40-60 mg/day) were enrolled. Patients received 20 mg/day dexamethasone (DM) orally (n = 25) or placebo (n = 26) for severe nausea in addition to metoclopramide (60 mg/day orally). At baseline the mean nausea intensity ratings in the DM and placebo groups were 8.0 and 7.4. At Day 8 they were 2.1 and 2.0, respectively. At Day 3 and Day 8, the mean difference in nausea intensity for the DM and placebo groups was 4.5 and 2.9 (P = 0.16) and 5.9 and 5.7 (P = 0.85), respectively. Improvement in appetite and fatigue were observed on Day 3 and Day 8 in both groups as compared with the baseline. Pain, vomiting, well-being, and quality of life remained unchanged in both groups at both times. We conclude that DM was not superior to placebo in the management of chronic nausea in our patients with advanced cancer.  相似文献   
997.
The incidence of human errors in the field of medicine is high. Two strategies to increase patient safety are simulator training and crew resource management (CRM) seminars, psychological courses on human performance and error management. AIM: To establish a CRM course combining psychological training on human error with simulator training. METHODS: Evaluation of a new 1-day training approach targeting physicians, nurses, and paramedics. The course was divided into four modules focusing on situation awareness, task management, teamwork, and decision-making. Each of the modules was set up according to a new six-step approach. The course started with an introduction into good CRM behaviour and an instructor demonstration of a simulator scenario. The participants had to debrief the instructors regarding their human performance. Step 2 was a lecture about the psychological background, and the third step consisted of psychological exercises related to the topic of the module. A psychological exercise in a medical context (MiniSim) made up step 4, which involved a patient simulator. The last two steps were a simulator scenario and a debriefing, as in other simulator courses. A psychologist and a physician were the facilitators in all steps. Two pilot courses were evaluated. RESULTS: Seventeen evaluation questionnaires were received. All participants rated the course as good (10) and very good (7). The psychological exercises were highly valued (good, 5; very good, 11 participants). Thirteen participants agreed that the course content was related to their work. CONCLUSION: We established the first course curriculum combining psychological teaching with simulator training for healthcare professionals in emergency medicine. Similar concepts using the six-step approach can be applied to other medical specialties.  相似文献   
998.
BACKGROUNDTo understand the features of a replicating vaccine that might drive potent and durable immune responses to transgene-encoded antigens, we tested a replication-competent adenovirus type 4 encoding influenza virus H5 HA (Ad4-H5-Vtn) administered as an oral capsule or via tonsillar swab or nasal spray.METHODSViral shedding from the nose, mouth, and rectum was measured by PCR and culturing. H5-specific IgG and IgA antibodies were measured by bead array binding assays. Serum antibodies were measured by a pseudovirus entry inhibition, microneutralization, and HA inhibition assays.RESULTSAd4-H5-Vtn DNA was shed from most upper respiratory tract–immunized (URT-immunized) volunteers for 2 to 4 weeks, but cultured from only 60% of participants, with a median duration of 1 day. Ad4-H5-Vtn vaccination induced increases in H5-specific CD4+ and CD8+ T cells in the peripheral blood as well as increases in IgG and IgA in nasal, cervical, and rectal secretions. URT immunizations induced high levels of serum neutralizing antibodies (NAbs) against H5 that remained stable out to week 26. The duration of viral shedding correlated with the magnitude of the NAb response at week 26. Adverse events (AEs) were mild, and peak NAb titers were associated with overall AE frequency and duration. Serum NAb titers could be boosted to very high levels 2 to 5 years after Ad4-H5-Vtn vaccination with recombinant H5 or inactivated split H5N1 vaccine.CONCLUSIONReplicating Ad4 delivered to the URT caused prolonged exposure to antigen, drove durable systemic and mucosal immunity, and proved to be a promising platform for the induction of immunity against viral surface glycoprotein targets.TRIAL REGISTRATIONClinicalTrials.gov NCT01443936 and NCT01806909.FUNDINGIntramural and Extramural Research Programs of the NIAID, NIH (U19 AI109946) and the Centers of Excellence for Influenza Research and Surveillance (CEIRS), NIAID, NIH (contract HHSN272201400008C).  相似文献   
999.
1000.
It is unclear why some species become successful invaders whilst others fail, and whether invasive success depends on pre-adaptations already present in the native range or on characters evolving de-novo after introduction. Ants are among the worst invasive pests, with Lasius neglectus and its rapid spread through Europe and Asia as the most recent example of a pest ant that may become a global problem. Here, we present the first integrated study on behavior, morphology, population genetics, chemical recognition and parasite load of L. neglectus and its non-invasive sister species L. turcicus. We find that L. neglectus expresses the same supercolonial syndrome as other invasive ants, a social system that is characterized by mating without dispersal and large networks of cooperating nests rather than smaller mutually hostile colonies. We conclude that the invasive success of L. neglectus relies on a combination of parasite-release following introduction and pre-adaptations in mating system, body-size, queen number and recognition efficiency that evolved long before introduction. Our results challenge the notion that supercolonial organization is an inevitable consequence of low genetic variation for chemical recognition cues in small invasive founder populations. We infer that low variation and limited volatility in cuticular hydrocarbon profiles already existed in the native range in combination with low dispersal and a highly viscous population structure. Human transport to relatively disturbed urban areas thus became the decisive factor to induce parasite release, a well established general promoter of invasiveness in non-social animals and plants, but understudied in invasive social insects.  相似文献   
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