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The aim of this safety study in mice was to determine in vivo toxicity and biodistribution potential of a single and multiple doses of L-glutamic acid-g-p(HEMA) polymeric nanoparticles as a drug delivery system. The single dose did not cause any lethal effect, and its acute oral LD50 was >2.000 mg/kg body weight (bw). Multiple doses (25, 50, or 100 mg/kg bw) given over 28 days resulted in no significant differences in body and relative organ weights compared to control. These results are supported by biochemical and histological findings. Moreover, nanoparticle exposure did not result in statistically significant differences in micronucleus counts in bone marrow cells compared to control. Nanoparticle distribution was time-dependent, and they reached the organs and even bone marrow by hour 6, as established by ex vivo imaging with the IVIS® spectrum imaging system. In conclusion, L-glutamic acid-g-p(HEMA) polymeric nanoparticles appear biocompatible and have a potential use as a drug delivery system.KEY WORDS: biocompatibility, blood biochemistry, genotoxicity, histology, in vivo toxicity, micronucleus test, polymers  相似文献   
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IntroductionNerve compression by anomalous masses located at the wrist and distal forearm is an infrequent condition. They may compress underlying structures in the carpal tunnel region, causing pain and paresthesias, which leads to the wrong diagnosis of carpal tunnel syndrome.Clinical casesWe present three cases of patients with symptomatology and clinical tests compatible with compression of the median nerve in the carpal tunnel but whose physical examination showed a soft mass in the distal region of the forearm which was compressing the median nerve, as demonstrated by ultrasound evaluation.DiscussionThe reported cases of accessory muscles or lipomas described in the literature as causes of median nerve compression clinic are mainly described only after the surgical decompression of the carpal tunnel, due to the maintenance of residual symptoms.ConclusionCareful examination with an ultrasound evaluation prior to surgery may help to identify these cases and help planning surgical treatment.  相似文献   
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Background: Children with Developmental Coordination Disorder (DCD) have difficulties performing daily activities which reflects negatively on participation, impacting their lives.

Objectives: To examine the effects of the cognitive orientation to daily occupational performance Approach (CO-OP Approach) protocol on occupational performance and satisfaction of Brazilian children who have DCD; to examine whether children could transfer strategies and skills learned during CO-OP to untrained goals.

Methods: A pre-post group comparison design with eight boys aged 6–10 years old. Children participated in 12 CO-OP sessions with their parents twice a week, with an extra session added to the protocol for parents´ orientation. The Canadian Occupational Performance Measure and the Performance Quality Rating Scale were used as outcome measures. The study was registered by the United States Institutes of Health at ClinicalTrials.gov (NCT03112746).

Results: Intervention resulted in higher, clinically and statistically significant, occupational performance measures according to parents, children’s, and external evaluators’ perspectives. All children improved occupational performance on their selected goals and five children could transfer the ability to use cognitive strategies to tasks not addressed in therapy.

Conclusions: This study provides initial directions for future research to investigate the applicability and to implement CO-OP approach on pediatric settings in Brazil.  相似文献   

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BackgroundThe efficacy of ticagrelor in the long-term post–ST-segment elevation myocardial infarction (STEMI) treated with fibrinolytic therapy remains uncertain.ObjectivesThe purpose of this study was to evaluate the efficacy of ticagrelor when compared with clopidogrel in STEMI patients treated with fibrinolytic therapy.MethodsThis international, multicenter, randomized, open-label with blinded endpoint adjudication trial enrolled 3,799 patients (age <75 years) with STEMI receiving fibrinolytic therapy. Patients were randomized to ticagrelor (180-mg loading dose, 90 mg twice daily thereafter) or clopidogrel (300- to 600-mg loading dose, 75 mg daily thereafter). The key outcomes were cardiovascular mortality, myocardial infarction, or stroke, and the same composite outcome with the addition of severe recurrent ischemia, transient ischemic attack, or other arterial thrombotic events at 12 months.ResultsThe combined outcome of cardiovascular mortality, myocardial infarction, or stroke occurred in 129 of 1,913 patients (6.7%) receiving ticagrelor and in 137 of 1,886 patients (7.3%) receiving clopidogrel (hazard ratio: 0.93; 95% confidence interval: 0.73 to 1.18; p = 0.53). The composite of cardiovascular mortality, myocardial infarction, stroke, severe recurrent ischemia, transient ischemic attack, or other arterial thrombotic events occurred in 153 of 1,913 patients (8.0%) treated with ticagrelor and in 171 of 1,886 patients (9.1%) receiving clopidogrel (hazard ratio: 0.88; 95% confidence interval: 0.71 to 1.09; p = 0.25). The rates of major, fatal, and intracranial bleeding were similar between the ticagrelor and clopidogrel groups.ConclusionAmong patients age <75 years with STEMI, administration of ticagrelor after fibrinolytic therapy did not significantly reduce the frequency of cardiovascular events when compared with clopidogrel. (Ticagrelor in Patients With ST Elevation Myocardial Infarction Treated With Pharmacological Thrombolysis [TREAT]; NCT02298088)  相似文献   
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In the work described here, our aim was to determine, in an elderly population, changes in muscle thickness (MT), cross-sectional area (CSA) and echo intensity (EI) of the quadriceps muscles at four time points (0, 5, 10 and 15 min; i.e., T0, T5, T10 and T15, respectively) after changing from a standing to supine position. Twenty-one elderly participants (14 men: 68.1 ± 4.6 y; 8 women: 66.8 ± 4.1 y) were evaluated at four time points. Rectus femoris CSA (RFCSA), MT and EI of the quadriceps femoris (QF) muscles were assessed. EI significantly increased from T0 to T5, T10 and T15 (p < 0.001), whereas no differences were observed between T5 and T15 in the rectus femoris (RFEI), vastus intermedius (VIEI) and quadriceps femoris (QFEI). No differences were observed between any time points in the RFCSA and MT of QF muscles. In summary, these results suggest that periods >5 min are not necessary to obtain consistent MT and EI measurements of quadriceps femoris muscles in the elderly population.  相似文献   
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Background and objectives

Sugamadex is a modified gamma‐cyclodextrin, the first selective agent for reversal of neuromuscular blockade induced by steroidal non‐depolarizing muscle relaxants, with greater affinity for rocuronium. In this article we present a case of severe bradycardia and asystole following sugammadex administration.

Case report

A 54‐year‐old male patient, ASA II, with a history of hypertension, dyslipidemia and obesity, who underwent an emergency umbilical herniorrhaphy under balanced general anesthesia. Intraoperative muscle relaxation was maintained with rocuronium. At the end of the surgery, the patient maintained a neuromuscular block with two TOF responses, and sugammadex (200 mg) was administered. About thirty seconds after its administration, the patient developed marked bradycardia (HR 30 bpm) followed by asystole.

Conclusions

Documented bradycardia and asystole were attributed to the administration of sugammadex. This case shows that, although rare, cardiac arrest is a possible adverse effect of this drug, and that the knowledge of this situation can be determinant for the patient's evolution.  相似文献   
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