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101.
Priapism is defined as an unwanted, prolonged, and painful erection which is unrelated to sexual stimulation. Some case studies suggest that priapism is an adverse effect of antipsychotic medications. In our case study a 30 year-old Iranian male with schizophrenia was experiencing recurrent priapism associated with quetiapine use. There are three interesting facts about this case: Firstly, the patient suffered priapism after even low dose consumption of quetiapine. Secondly, this case had experienced priapism with risperidone, olanzapine, and even clozapine in the past, suggesting a possible pharmacodynamic interaction of antipsychotics and inner biological traits in this particular case. Thirdly, priapism induced by low dose quetiapine was resolved after cigarette smoking.  相似文献   
102.

Purpose

Conditions such as lung cancer currently lack non-invasively targetable and controlled release topical inhalational therapies. Superparamagnetic iron-oxide nanoparticles (SPIONs) have shown promising results as a targetable therapy. We aimed to fabricate and test the in-vitro performance of particles with SPION and drug within a lipid matrix as a potentially targetable and thermo-sensitive inhalable drug-delivery system.

Methods

Budesonide and SPIONs were incorporated into lipid particles using oil-in-water emulsification. Particles size, chemical composition, responsiveness to magnetic field, thermosensitiveness and inhalation performance in-vitro were investigated.

Results

Particles of average diameter 2?C4???m with budesonide and SPIONs inside the lipid matrix responded to a magnetic field with 100% extraction at a distance of 5?mm. Formulations were shown to have accelerated rate of drug release at hyperthermic temperatures (45°C)??controlled release. The produced inhalation dry powder presented promising inhalation performance, with an inhalable fine particle fraction of 30%.

Conclusions

The lipid system presented thermo-sensitive characteristics, suitable for controlled delivery, the model drug and SPION loaded lipid system was magnetically active and movable using simple permanent magnets, and the system demonstrates promise as an effective drug vehicle in targeted and controlled inhalation therapy.  相似文献   
103.
Proteases that degrade the amyloid-β peptide (Aβ) are important in protecting against Alzheimer's disease (AD), and understanding these proteases is critical to understanding AD pathology. Endopeptidases sensitive to inhibition by thiorphan and phosphoramidon are especially important, because these inhibitors induce dramatic Aβ accumulation (~30- to 50-fold) and pathological deposition in rodents. The Aβ-degrading enzyme neprilysin (NEP) is the best known target of these inhibitors. However, genetic ablation of NEP results in only modest increases (~1.5- to 2-fold) in Aβ, indicating that other thiorphan/phosphoramidon-sensitive endopeptidases are at work. Of particular interest is the NEP homolog neprilysin 2 (NEP2), which is thiorphan/phosphoramidon-sensitive and degrades Aβ. We investigated the role of NEP2 in Aβ degradation in vivo through the use of gene knockout and transgenic mice. Mice deficient for the NEP2 gene showed significant elevations in total Aβ species in the hippocampus and brainstem/diencephalon (~1.5-fold). Increases in Aβ accumulation were more dramatic in NEP2 knockout mice crossbred with APP transgenic mice. In NEP/NEP2 double-knockout mice, Aβ levels were marginally increased (~1.5- to 2-fold), compared with NEP(-/-)/NEP2(+/+) controls. Treatment of these double-knockout mice with phosphoramidon resulted in elevations of Aβ, suggesting that yet other NEP-like Aβ-degrading endopeptidases are contributing to Aβ catabolism.  相似文献   
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Abdominal aortic aneurysm (AAA) is among a number of vascular disorders to be recently associated with a common allelic variant situated on chromosome 9p21. To further assess the significance of this region of the genome in AAA development, we genotyped the sequence variation tagged by rs10757278 in two geographically independent cohorts of patients and compared them to matched controls. We also assessed the impact of this variant on AAA growth rate in cohorts with a median surveillance period of 3.2 and 4.5 years. Using meta-analysis to combine the findings of both cohorts, we found a significant association between rs10757278-G and the presence of AAA (OR (95%CI) 1.38 (1.04-1.82) P=0.03), an effect size completely consistent with that originally reported. rs10757278 was not significantly associated with altered AAA growth rate in either cohort.  相似文献   
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Cardiovascular morbidity and mortality are highly prevalent among patients with chronic renal failure (CRF). Endothelial dysfunction is regarded as the initial reversible step in the development of atherosclerosis and has been demonstrated in all stages of renal failure. Non-invasive techniques to assess endothelial function have been recently developed and have been proven to predict future mortality in adults. We aimed to assess endothelial function in children with stage 4 chronic kidney disease (CKD 4) on conservative treatment, using a-non invasive, high-resolution, ultrasound Doppler study of the brachial artery flow, correlating it with other clinical and laboratory parameters. This study included 34 children with CKD 4 on conservative treatment who were compared with 30 healthy controls. Flow-mediated dilatation (FMD), nitroglycerin-mediated dilatation (NTG-MD) and FMD/NTG-MD ratio were estimated. FMD was abnormal (< 5%) in 24 patients (71%). FMD and FMD/NTG-MD ratio were significantly lower in patients than in controls (P = 0.001 and P = 0.01, respectively). FMD correlated positively with serum calcium and negatively with alkaline phosphatase. We concluded that endothelial dysfunction is present in children with CKD 4 on conservative treatment and may reflect increased atherogenic and thrombogenic properties of the endothelium, contributing to subsequent adverse cardiovascular outcome.  相似文献   
110.
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