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991.
992.
993.
Mustafa Hassan Kaki M. York Haihong Li Qin Li David S. Sheps 《Journal of nuclear cardiology》2007,14(3):308-313
Background Reduced left ventricular ejection fraction (LVEF) is a risk factor for poor outcomes in patients with coronary artery disease
(CAD). Mental stress-induced myocardial ischemia (MSIMI) also identifies a subset of CAD patients at increased risk for future
cardiovascular events. Susceptibility to MSIMI in patients with CAD and reduced LVEF is unknown.
Methods and Results We enrolled 182 patients (67 women) with a mean age of 64 years and a documented history of CAD in this study. Baseline resting
ejection fraction was determined by use of technetium 99m sestamibi gated single photon emission computed tomography. Abnormal
LVEF was defined as less than 45% for men and less than 50% for women (based on published norms for our software [Cedars-Sinai
Medical Center]). All participants underwent mental stress testing with a public speaking task. Rest/stress myocardial perfusion
single photon emission computed tomography was performed via conventional methodology. Images were visually compared for number
and severity of perfusion defects by use of a scoring method from 0 to 4. A summed difference score was calculated as the
difference between summed stress and rest scores. A score of greater than 3 was considered abnormal. MSIMI developed in 19%
of patients with normal LVEF and 31% of those with reduced LVEF. There is no statistically significant difference between
the two groups (P=.11).
Conclusions CAD patients with left ventricular dysfunction are equally susceptible to MSIMI as those with normal LVEF.
This study was supported by grants HL 070265 and HL 072059 from the National Heart. Lung, and Blood Institute. This material
is also the result of work supported by resources and with the use of facilities at the Department of Veterans. Affairs Medical
Center, Gainesville, Fla. 相似文献
994.
Lee L. Eckhardt MD Amanda L. Farley MS Esther Rodriguez MD Karen Ruwaldt BS Daniel Hammill David J. Tester BS Michael J. Ackerman MD PhD Jonathan C. Makielski MD 《Heart rhythm》2007,4(3):323-329
BACKGROUND: Loss-of-function mutations in the KCNJ2 cause approximately 50% of Andersen-Tawil Syndrome (ATS) characterized by a classic triad of periodic paralysis, ventricular arrhythmia, and dysmorphic features. Do KCNJ2 mutations occur in patients lacking this triad and lacking a family history of ATS? OBJECTIVES: The purpose of this study was to identify and characterize mutations in the KCNJ2-encoded inward rectifier potassium channel Kir2.1 from patients referred for genetic arrhythmia testing. METHODS: Mutational analysis of KCNJ2 was performed for 541 unrelated patients. The mutations were made in wild type (WT) and expressed in COS-1 cells and voltage clamped for ion currents. RESULTS: Three novel missense mutations (R67Q, R85W, and T305A) and one known mutation (T75M) were identified in 4/249 (1.6%) patients genotype-negative for other known arrhythmia genes with overall incidence 4/541 (0.74%). They had prominent U-waves, marked ventricular ectopy, and polymorphic ventricular tachycardia but no facial/skeletal abnormalities. Periodic paralysis was present in only one case. Outward current was decreased to less than 5% of WT for all mutants expressed alone. Co-expression with WT (simulating heterozygosity) caused a marked dominant negative effect for T75M and R82W, no dominant negative effect for R67Q, and a novel selective enhancement of inward rectification for T305A. CONCLUSIONS: KCNJ2 loss of function mutations were found in approximately 1% of patients referred for genetic arrhythmia testing that lacked criteria for ATS. Characterization of three new mutations identified a novel dominant negative effect selectively reducing outward current for T305A. These results extend the range of clinical phenotype and molecular phenotype associated with KCNJ2 mutations. 相似文献
995.
Acute selective serotonin reuptake inhibitors increase conditioned fear expression: blockade with a 5-HT(2C) receptor antagonist. 总被引:3,自引:0,他引:3
Nesha S Burghardt David E A Bush Bruce S McEwen Joseph E LeDoux 《Neuropsychopharmacology》2007,62(10):1111-1118
BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs) effectively treat various anxiety disorders, although symptoms of anxiety are often exacerbated during early stages of treatment. We previously reported that acute treatment with the SSRI citalopram enhances the acquisition of auditory fear conditioning, which is consistent with the initial anxiogenic effects reported clinically. Here, we extend our findings by assessing the effects of acute SSRI treatment on the expression of previously acquired conditioned fear. METHODS: Rats underwent fear conditioning drug-free. Tone-evoked fear responses were tested after drug treatment the following day. This protocol more closely resembles the clinical setting than pre-conditioning treatment, because it evaluates effects of treatment on a pre-existing fear rather than on the formation of a new fear memory. RESULTS: A single pre-testing injection of the SSRIs citalopram or fluoxetine significantly increased fear expression. There was no effect of the antidepressant tianeptine or the norepinephrine reuptake inhibitor tomoxetine, indicating that this effect is specific to SSRIs. The SSRI-induced enhancement in fear expression was not blocked by tropisetron, a 5-HT(3) receptor antagonist, but was blocked by SB 242084, a specific 5-HT(2C) receptor antagonist. CONCLUSIONS: Enhanced activation of 5-HT(2C) receptors might be a mechanism for the anxiogenic effects of SSRIs observed initially during treatment. 相似文献
996.
997.
Efficacy and safety of transcranial magnetic stimulation in the acute treatment of major depression: a multisite randomized controlled trial. 总被引:6,自引:0,他引:6
John P O'Reardon H Brent Solvason Philip G Janicak Shirlene Sampson Keith E Isenberg Ziad Nahas William M McDonald David Avery Paul B Fitzgerald Colleen Loo Mark A Demitrack Mark S George Harold A Sackeim 《Neuropsychopharmacology》2007,62(11):1208-1216
BACKGROUND: We tested whether transcranial magnetic stimulation (TMS) over the left dorsolateral prefrontal cortex (DLPFC) is effective and safe in the acute treatment of major depression. METHODS: In a double-blind, multisite study, 301 medication-free patients with major depression who had not benefited from prior treatment were randomized to active (n = 155) or sham TMS (n = 146) conditions. Sessions were conducted five times per week with TMS at 10 pulses/sec, 120% of motor threshold, 3000 pulses/session, for 4-6 weeks. Primary outcome was the symptom score change as assessed at week 4 with the Montgomery-Asberg Depression Rating Scale (MADRS). Secondary outcomes included changes on the 17- and 24-item Hamilton Depression Rating Scale (HAMD) and response and remission rates with the MADRS and HAMD. RESULTS: Active TMS was significantly superior to sham TMS on the MADRS at week 4 (with a post hoc correction for inequality in symptom severity between groups at baseline), as well as on the HAMD17 and HAMD24 scales at weeks 4 and 6. Response rates were significantly higher with active TMS on all three scales at weeks 4 and 6. Remission rates were approximately twofold higher with active TMS at week 6 and significant on the MADRS and HAMD24 scales (but not the HAMD17 scale). Active TMS was well tolerated with a low dropout rate for adverse events (4.5%) that were generally mild and limited to transient scalp discomfort or pain. CONCLUSIONS: Transcranial magnetic stimulation was effective in treating major depression with minimal side effects reported. It offers clinicians a novel alternative for the treatment of this disorder. 相似文献
998.
R. Parker Ward MD Mouaz H. Al-Mallah MD Gabriel B. Grossman MD PhD Christopher L. Hansen MD Robert C. Hendel MD Todd C. Kerwin MD Benjamin D. McCallister Jr MD Rupa Mehta MD Donna M. Polk MD MPH Peter L. Tilkemeier MD Aseem Vashist MD Kim Allan Williams MD David G. Wolinsky MD Edward P. Ficaro PhD 《Journal of nuclear cardiology》2007,14(6):911-e38
999.
1000.
Radiation therapy has been a major treatment option for patients with prostate cancer with documented efficacy over the last 30 years. Recent research has shown a correlation between improved local control, disease-free survival, and overall survival and dose delivered. Excessive dose to the rectum is one of the leading causes of morbidity in the treatment of prostate cancer. The RTOG and others have suggested dose limitations based on various treatment parameters. Intensity-modulated radiation therapy (IMRT) is becoming more widely used, with the goal of improving dose coverage while limiting morbidity. In an effort to evaluate our inverse-planning technique relative to our forward-planned technique based on rectal dose, 2 plans were generated on 10 patients. One plan was generated with 9-field forward planning, using 2 posterior obliques to decrease dose to the rectum. The other plan utilized inverse IMRTplanning. To evaluate dose to the rectum, we compared the dose gradient from the posterior edge of the prostate across the anterior third of the rectal wall. This gradient, which is not part of the IMRT planning objectives, proved useful in assessing plan differences, and led to new dose objectives for certain IMRT plans. 相似文献