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841.
CE Beyer Q Lin B Platt J Malberg G Hornby KM Sullivan DL Smith T Lock PJ Mitchell NT Hatzenbuhler DA Evrard BL Harrison R Magolda MN Pangalos LE Schechter S Rosenzweig-Lipson TH Andree 《British journal of pharmacology》2009,157(2):307-319
Background and purpose
As a combination of 5-HT selective reuptake inhibitor (SSRI) with 5-HT1A receptor antagonism may yield a rapidly acting antidepressant, WAY-211612, a compound with both SSRI and 5-HT1A receptor antagonist activities, was evaluated in preclinical models.Experimental approach
Occupancy studies confirmed the mechanism of action of WAY-211612, while its in vivo profile was characterized in microdialysis and behavioural models.Key results
WAY-211612 inhibited 5-HT reuptake (Ki = 1.5 nmol·L−1; KB = 17.7 nmol·L−1) and exhibited full 5-HT1A receptor antagonist activity (Ki = 1.2 nmol·L−1; KB = 6.3 nmol·L−1; Imax 100% in adenyl cyclase assays; KB = 19.8 nmol·L−1; Imax 100% in GTPγS). WAY-211612 (3 and 30 mg·kg−1, po) occupied 5-HT reuptake sites in rat prefrontal cortex (56.6% and 73.6% respectively) and hippocampus (52.2% and 78.5%), and 5-HT1A receptors in the prefrontal cortex (6.7% and 44.7%), hippocampus (8.3% and 48.6%) and dorsal raphe (15% and 83%). Acute or chronic treatment with WAY-211612 (3–30 mg·kg−1, po) raised levels of cortical 5-HT approximately twofold, as also observed with a combination of an SSRI (fluoxetine; 30 mg·kg−1, s.c.) and a 5-HT1A antagonist (WAY-100635; 0.3 mg·kg−1, s.c). WAY-211612 (3.3–30 mg·kg−1, s.c.) decreased aggressive behaviour in the resident-intruder model, while increasing the number of punished crossings (3–30 mg·kg−1, i.p. and 10–56 mg·kg−1, po) in the mouse four-plate model and decreased adjunctive drinking behaviour (56 mg·kg−1, i.p.) in the rat scheduled-induced polydipsia model.Conclusions and implications
These findings suggest that WAY-211612 may represent a novel antidepressant. 相似文献842.
843.
Background
Nasal modes of respiratory support cause variable amounts of gastric dilatation which may increase gastro-oesophageal reflux (GER) in preterms. To compare the incidence of GER in nasally ventilated, preterm babies with controls (babies not on ventilation). Type of study: A prospective, observational comparative study.Method
Twenty-three preterm babies of gestational age 28–36 weeks and weight ranging between 1,000 g and < 2,500 g on either nasal continuous positive airway pressure (nCPAP) or nasal intermittent positive pressure venti-lation (nIPPV) were assessed for GER. They were compared with controls not on ventilation some of who were test babies when off ventilation (subgroup A) and some were unrelated babies not on ventilator but matched for gestational age and weight with test babies (subgroup B). All babies were subjected to continuous, oesophageal pH monitoring with dual sensor (upper and lower oesophageal) catheters. Reflux index (RI) was calculated as the percentage of study time the lower oesophageal pH was < 4. Primary outcome was the RI in the test and controls groups. Secondary outcome was the temporal relation of the reflux with symptoms if any. Numerical data were shown as mean with standard deviation and statistical comparisons were done using the χ2-test, Fischer test, and t-test wherever applicable.Results
The RI was higher in ventilated babies as compared to the control group, particularly in the subgroup A, where test babies formed their own controls. Grade IV reflux (7 cases) was seen only in the ventilated babies. There was no difference in the incidence of GER in babies on nCPAP as compared with nIPPV. Grade IV reflux could not be reliably predicted by RI alone. No definite temporal relation between episodes of reflux and symptoms could be determined in this study.Conclusion
There is an increase in GER in preterms on nasal modes of ventilation. A combination of upper (pharyngeal) and lower oesophageal sensors are preferred to a single lower oesophageal sensor when assessing GER by oesophageal pHmetry in neonates. 相似文献844.
845.
Ivanov D Hamby SE Stenson PD Phillips AD Kehrer-Sawatzki H Cooper DN Chuzhanova N 《Human mutation》2011,32(6):620-632
Mutations associated with tumorigenesis may either arise somatically or can be inherited through the germline. We performed a comparison of somatic, germline, shared (found in both soma and germline) and somatic recurrent mutational spectra for 17 human tumor suppressor genes, which focused upon missense single base‐pair substitutions and microdeletions/microinsertions. Somatic and germline mutational spectra were similar in relation to C.G>T.A transitions but differed with respect to the frequency of A.T>G.C, A.T>T.A, and C.G>A.T substitutions. Shared missense mutations were characterized by higher mutability rates, greater physicochemical differences between wild‐type and mutant residues, and a tendency to occur in evolutionarily conserved residues and within CpG/CpHpG oligonucleotides. Mononucleotide runs (≥4 bp) were identified as hotspots for shared microdeletions/microinsertions. Both germline and somatic microdeletions/microinsertions were found to be significantly overrepresented within the “indel‐hotspot” motif, GTAAGT. Using a naïve Bayes' classifier trained to discriminate between five missense mutation groups, 63% of mutations in our dataset were on average correctly recognized. Applying this classifier to an independent dataset of probable driver mutations, we concluded that ~50% of these somatic missense mutations possess features consistent with their being either shared or recurrent, suggesting that a disproportionate number of such lesions are likely to be drivers of tumorigenesis. Hum Mutat 32:1–13, 2011. © 2011 Wiley‐Liss, Inc. 相似文献
846.
Michael T Milano Daniel J Haraf Kerstin M Stenson Mary Ellyn Witt Cathy Eng Bharat B Mittal Athanassios Argiris Harold Pelzer Mark F Kozloff Everett E Vokes 《Clinical cancer research》2004,10(15):4922-4932
PURPOSE: We previously demonstrated high locoregional control, in patients with poor-prognosis head and neck cancer (HNC), using paclitaxel, 5-fluorouracil, hydroxyurea, and concomitant hyperfractionated radiotherapy. In the present phase I trial, gemcitabine, a novel antimetabolite with strong radiation-enhancing activity, replaces hydroxyurea. We sought to determine the recommended phase II dose and clinical efficacy in poor-prognosis HNC patients. EXPERIMENTAL DESIGN: Seventy-two patients enrolled. Eligibility criteria included recurrent or second primary HNC, metastases or expected 2-year survival <20%. Chemoradiotherapy consisted of 5-fluorouracil, 600 mg/m(2)/d, for 5 days; paclitaxel, 100 mg/m(2) on Day 1; and concurrent 1.5 Gy twice-daily radiation for 5 days. Gemcitabine was dose escalated, 50-300 mg/m(2) on day 1. Cycles repeated every 14 days until the completion of chemoradiation. Dose-limiting toxicities (DLTs) included: neutropenic fever; grade > or =4 neutropenia or thrombocytopenia for >4 days; grade > or =4 mucositis or dermatitis for >7 days; or grade 3 toxicity necessitating chemotherapy dose reductions. Non-DLT dose reductions in 5-fluorouracil and/or paclitaxel were allowed. RESULTS: Seventy-nine percent of assessable patients experienced a clinical response. Five-year actuarial survival is 33.0%, and locoregional control is 61.4%. The recommended phase II dose of gemcitabine in this regimen is 100 mg/m(2) during cycles 1-5 (1 of 7 patients with DLT) or 200 mg/m(2) delivered only during cycles 3-5 (3 of 19 with DLT). Grades 3 and 4 mucositis (56 and 21%, respectively) and dermatitis (25 and 21%, respectively) were common. CONCLUSIONS: Gemcitabine, 5-fluorouracil, paclitaxel, and twice-daily radiation, delivered on alternating weeks, is active in patients with poor-prognosis HNC, although severe mucositis limits the clinical applicability of this regimen. Refinements in radiotherapy, including intensity-modulated radiation therapy, may improve the tolerance for this regimen. 相似文献
847.
848.
Walter Stenson 《American journal of surgery》1940,48(3):599-600
849.
Anthony R. Stenson Paul Whitney John M. Hinson Devon A. Hansen Darian Lawrence-Sidebottom Lillian Skeiky Samantha M. Riedy Courtney A. Kurinec Hans P. A. Van Dongen 《Journal of sleep research》2023,32(2):e13744
Sleep deprivation consistently decreases vigilant attention, which can lead to difficulty in performing a variety of cognitive tasks. However, sleep-deprived individuals may be able to compensate for degraded vigilant attention by means of top-down attentional control. We employed a novel task to measure the degree to which individuals overcome impairments in vigilant attention by using top-down attentional control, the Flexible Attentional Control Task (FACT). The FACT is a two-choice task that has trials with valid, invalid, and neutral cues, along with an unexpected switch in the probability of cue validity about halfway in the task. The task provides indices that isolate performance components reflecting vigilant attention and top-down attentional control. Twelve healthy young adults completed an in-laboratory study. After a baseline day, the subjects underwent 39 hours of total sleep deprivation (TSD), followed by a recovery day. The FACT was administered at 03:00, 11:00, and 19:00 during sleep deprivation (TSD condition) and at 11:00 and 19:00 after baseline sleep and at 11:00 after recovery sleep (rested condition). When rested, the subjects demonstrated both facilitation and interference effects on cued trials. While sleep deprived, the subjects showed vigilant attention deficits on neutral cue trials, and an impaired ability to reduce these deficits by using predictive contextual cues. Our results indicate that the FACT can dissociate vigilant attention from top-down attentional control. Furthermore, they show that during sleep deprivation, contextual cues help individuals to compensate partially for impairments in vigilant attention, but the effectiveness of top-down attentional control is diminished. 相似文献