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OBJECTIVE: To evaluate the efficacy and tolerability of treatment with a combination of sumatriptan 50 mg (encapsulated) and naproxen sodium 500 mg administered concurrently in the acute treatment of migraine. BACKGROUND: The pathogenesis of migraine involves multiple peripheral and central neural mechanisms that individually have been successful targets for acute (abortive) and preventive treatment. This suggests that multi-mechanism therapy, which acts on multiple target sites, may confer improved efficacy and symptom relief for patients with migraine. DESIGN AND METHODS: This was a multicenter, randomized, double-blind, double-dummy, placebo-controlled, four-arm study. Participants (n = 972) treated a single moderate or severe migraine attack with placebo, naproxen sodium 500 mg, sumatriptan 50 mg, or a combination of sumatriptan 50 mg and naproxen sodium 500 mg. In the latter two treatment arms, the sumatriptan tablets were encapsulated in order to achieve blinding of the study. RESULTS: In the sumatriptan plus naproxen sodium group, 46% of subjects achieved 24-hour pain relief response (primary endpoint), which was significantly more effective than sumatriptan alone (29%), naproxen sodium alone (25%), or placebo (17%) (P < .001). Two-hour headache response also significantly favored the sumatriptan 50 mg plus naproxen sodium 500 mg therapy (65%) versus sumatriptan (49%), naproxen sodium (46%), or placebo (27%) (P < .001). A similar pattern of between-group differences was observed for 2-hour pain-free response and sustained pain-free response (P < .001). The incidence of headache recurrence up to 24 hours after treatment was lowest in the sumatriptan plus naproxen sodium group (29%) versus sumatriptan alone (41%; P = .048), versus naproxen sodium alone (47%; P= .0035), and versus placebo (38%; P= .08). The incidences of the associated symptoms of migraine were significantly lower at 2 hours following sumatriptan 50 mg plus naproxen sodium 500 mg treatment versus placebo (P < .001). The frequencies and types of adverse events reported did not differ between treatment groups, with dizziness and somnolence being the most common. CONCLUSIONS: This is among the first prospective studies to demonstrate that multi-mechanism acute therapy for migraine, combining a triptan and an analgesic, is well tolerated and offers improved clinical benefits over monotherapy with these selected standard antimigraine treatments. Specifically, sumatriptan 50 mg (encapsulated) and naproxen sodium 500 mg resulted in significantly superior pain relief as compared to monotherapy with either sumatriptan 50 mg (encapsulated) or naproxen sodium 500 mg for the acute treatment of migraine. Because encapsulation of the sumatriptan for blinding purposes may have altered its pharmacokinetic profile and thereby decreased the efficacy responses, additional studies are warranted that do not involve encapsulation of the active treatments and assess the true onset of action of multi-mechanism therapy in migraine. This study did show that the combination of sumatriptan and naproxen sodium was well tolerated and that there was no significant increase in the incidence of adverse events compared to monotherapy.  相似文献   
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Insulin resistance plays a primary role in the development of type 2 diabetes and may be related to alterations in fat metabolism. Recent studies have suggested that local accumulation of fat metabolites inside skeletal muscle may activate a serine kinase cascade involving protein kinase C-theta (PKC-theta), leading to defects in insulin signaling and glucose transport in skeletal muscle. To test this hypothesis, we examined whether mice with inactivation of PKC-theta are protected from fat-induced insulin resistance in skeletal muscle. Skeletal muscle and hepatic insulin action as assessed during hyperinsulinemic-euglycemic clamps did not differ between WT and PKC-theta KO mice following saline infusion. A 5-hour lipid infusion decreased insulin-stimulated skeletal muscle glucose uptake in the WT mice that was associated with 40-50% decreases in insulin-stimulated tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1) and IRS-1-associated PI3K activity. In contrast, PKC-theta inactivation prevented fat-induced defects in insulin signaling and glucose transport in skeletal muscle. In conclusion, our findings demonstrate that PKC-theta is a crucial component mediating fat-induced insulin resistance in skeletal muscle and suggest that PKC-theta is a potential therapeutic target for the treatment of type 2 diabetes.  相似文献   
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fMRI has been used to characterize the abnormal brain activity after stroke during attempted motor tasks, the change in brain activity accompanying spontaneous motor recovery, and response to interventions. However, many patients after stroke exhibit abnormally high effort during attempted movements, including undesired movements of the supposed quiescent, uninvolved limb, which could confound fMRI measures. We developed a method of identifying the potentially confounded scans, using EMG measures of muscle activity in the supposed quiescent limb. We found that there was no interference in the MRI signal from the EMG data acquisition system, during simultaneous use of both MRI and EMG. For EMG signal acquisition, as expected, we were able to identify EMG signal free of MRI noise contamination during the inter-scan interval between any given scan and its subsequent scan. We tested movement of the involved limb. We determined that when undesired muscle activation was present in the uninvolved, supposed quiescent limb, there was an over-estimation of the number of active voxels ranging from 10 to 11, depending upon the ROI.  相似文献   
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Thirty-nine critically ill infants with pulmonary disease received tolazoline because of severe hypoxemia refractory to administration of 100% O2 and mechanical ventilation. Twenty-seven (69%) of the infants responded with an increase in PaO2 greater than or equal to 20 torr in the first umbilical arterial gas after completion of the initial ten-minute infusion (1 to 2 mg/kg) of the drug. A response was not correlated with survival. The overall survival was 46%, essentially unchanged from our previous report (44%). Infants with hyaline membrane disease had the poorest survival rate (33%). Complications associated with the use of tolazoline occurred in 82% of the infants. A hypotensive reaction, defined as a 25% decrease in mean arterial pressure from the pre-tolazoline level, occurred in 67% of the infants, and more commonly in the infants with RDS (87%). In 11 infants who did not respond to the initial dose of tolazoline, the dose was increased up to 10 mg/kg/hour; only one infant responded, and eight (73%) had a hypotensive reaction.  相似文献   
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Cells of the intestinal mucosa of the infant and adult rat maintain a pattern of continuous growth, accumulating structural and functional proteins and lipids while migrating the length of the villus column. Cells of jejunal and ileal segments were fractionated sequentially from villus tip to inner crypt and distribution patterns were determined for DNA, total protein, cholesterol, phospholipid, and disaccharidases. Patterns of increasing ratios of protein, lipids, and disaccharidases to DNA were maintained to villus tips, with only slight fall-off of enzymes observed. Distribution profiles of disaccharidases, when computed relative to protein (as seen in previous reports), show distortion of the true cellular distribution pattern of these enzymes as determined by the DNA content of the fractions. Wide variation in cell protein concentrations was evident between jejunal and ileal segments in pre- and postweaned rats. Ileal cells of the suckling rat contained particularly high protein concentrations, which appeared to be largely transitory in nature and related to food intake. Cholesterol and phospholipids were found to be concentrated in the microvillus membrane and account for a significantly large fraction of the cellular content of these lipids.  相似文献   
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The toxicology laboratory can fill an important role in improving patient care. Whether the service provided by the laboratory is specifically in support of a pediatric population or devoted more to the entire hospital population, the considerations involved in its configuration are the same. These considerations involve establishment of an open dialogue between the laboratory and clinical staff, an integrated and comprehensive analytic approach, and provision of reliable laboratory data in a timely fashion.  相似文献   
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