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Growing interest in the clinical use of cannabidiol (CBD) as adjuvant therapy for pediatric refractory epileptic encephalopathy emphasizes the need for drug treatment optimization. The aim of this study was to characterize the pharmacokinetics of CBD in pediatric patients with refractory epileptic encephalopathy receiving an oil‐based oral solution. To evaluate CBD concentrations, six serial blood samples per patient were collected after the morning dose of CBD, at least 21 days after the beginning of treatment. Twelve patients who received a median (range) dose of 12.2 (5.3‐19.4) mg/kg/d (twice daily) were included in the analysis. Median (range) CBD time to maximum plasma concentration, maximum plasma concentration, and area under the concentration versus time curve up to 6 hours after dosing were 3.2 hours (1.9‐6.2), 49.6 ng/mL (14.4‐302.0), and 226.3 ng ? h/mL (70.5‐861.3), respectively. CBD systemic exposure parameters were in the lower range of previous reports in pediatric patients receiving doses in a similar range. Most of our patients (83%) showed little CBD plasma level fluctuation during a dosing interval, comparable to that encountered after oral administration of an extended release drug delivery system. CDB administration was generally safe and well tolerated, and a novel levothyroxine‐CBD interaction was recorded. Similar to other studies, large interindividual variability in CBD exposure was observed, encouraging the use of CBD therapeutic drug monitoring.  相似文献   
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BackgroundSpinal muscular atrophy (SMA) is a neuromuscular disease caused by homozygous deletion of SMN1 exons 7 and 8. However, exon 8 is retained in some cases, where SMN2 exon 7 recombines with SMN1 exon 8, forming a hybrid SMN gene. It remains unknown how the hybrid SMN gene contribute to the SMA phenotype.MethodWe analyzed 515 patients with clinical suspicion for SMA. SMN1 exons 7 and 8 deletion was detected by PCR followed by enzyme digestion. Hybrid SMN genes were further analyzed by nucleotide sequencing. SMN2 copy number was determined by real-time PCR.ResultsSMN1 exon 7 was deleted in 228 out of 515 patients, and SMN1 exon 8 was also deleted in 204 out of the 228 patients. The remaining 24 patients were judged to carry a hybrid SMN gene. In the patients with SMN1 exon 7 deletion, the frequency of the severe phenotype was significantly lower in the patients with hybrid SMN gene than in the patients without hybrid SMN gene. However, as for the distribution of SMN2 exon 7 copy number among the clinical phenotypes, there was no significant difference between both groups of SMA patients with or without hybrid SMN gene.ConclusionHybrid SMN genes are not rare in Japanese SMA patients, and it appears to be associated with a less severe phenotype. The phenotype of patients with hybrid SMN gene was determined by the copy number of SMN2 exon 7, as similarly for the patients without hybrid SMN gene.  相似文献   
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Purpose

Total hip arthroplasty (THA) is a widespread option for treating hip osteoarthritis. Peri-prosthetic complications after THA represent a common event influencing patient outcome and costs. The purpose of this paper is to report the use of ultrasonography (US) to detect peri-prosthetic complications in symptomatic patients who underwent THA.

Methods

We retrospectively reviewed the records of patients with THA who underwent imaging evaluation between January 2009 and December 2012 at two different institutions. We evaluated the presence/absence of superficial and/or deep peri-prosthetic collections as well as the presence/absence of a cutaneous sinus tract. For patients who underwent both MRI and US, a concordance correlation analysis between US and MR findings was performed.

Results

In the reference period, 532 symptomatic patients (mean age ± standard deviation 74 ± 12 years) underwent X-ray and MRI examinations for suspected peri-prosthetic complications. Among them, 111 (20.9 %) underwent also US. Overall, 108 patients underwent both US and MRI. US findings included 67 superficial collections, 48 subcutaneous fistulas, 74 deep peri-prosthetic collections. Twenty-four patients had solid, mass-like peri-prosthetic collections. In 11 patients, no peri-prosthetic complications were seen. MRI findings included 68 superficial collections, 49 subcutaneous fistulas, 79 deep peri-prosthetic collections. Twenty-four patients had solid, mass-like peri-prosthetic collections. In four patients, no peri-prosthetic complications were seen. Concordance analysis between US and MRI findings showed almost perfect agreement (k ≥ 0.89).

Conclusion

US is an efficient and practical imaging modality to evaluate peri-prosthetic complications in patients with THA, being almost comparable to MRI in detecting and characterizing these complications.  相似文献   
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AIMS: To evaluate possible modifications in the manganese superoxide dismutase (MnSOD) activity during neoplastic transformation of a cirrhotic liver and to find out whether its assessment may have predictive value to identify cirrhotic patients at a higher risk of hepatocellular carcinoma (HCC). METHODS: Seventy-one consecutive subjects with Child-Pugh class A liver cirrhosis were recruited. At the time of enrolment, HCC was diagnosed in 20 cirrhotic patients. The 51 cirrhotic patients without HCC were followed up for the occurrence of tumour by 6-monthly screening for 7 years. During follow-up, 16 patients developed HCC. Seventy healthy subjects formed the control group. MnSOD activity was assayed spectrophotometrically. RESULTS: Serum MnSOD activity was significantly lower in 70 healthy subjects compared with 51 cirrhotic patients and 20 cirrhotic patients with HCC. Cirrhotic patients who developed HCC during follow-up showed significantly higher values of MnSOD activity than HCC-free patients. The best cut-off of MnSOD activity was 0.40 U/ml. At this cut-off, chi2 analysis revealed that MnSOD activity was significantly different between the HCC-free cirrhotic patients and cirrhotic patients who developed HCC. CONCLUSION: The present findings suggest that during neoplastic transformation of cirrhotic liver, an increase in MnSOD activity may occur already during the precancerous phase, making this enzyme a probable malignancy-associated parameter.  相似文献   
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This review concentrates on the most important developments since the WHO classification of 2005. In particular, the identification of specific translocations is revolutionising the way salivary tumours are considered and will have a major impact on future diagnostic practice. This is true so far in four malignancies: mammary analogue secretory, mucoepidermoid, adenoid cystic and hyalinising clear cell carcinomas. In each, the gene rearrangement is found in 80 % or more of cases. Two 2014 publications have added further possible candidates with molecular abnormalities to the list (cribriform adenocarcinoma of the tongue and minor salivary glands and epithelial-myoepithelial carcinoma), but these findings have yet to be confirmed by other investigators. The advances in molecular pathology have also allowed re-evaluation of the morphology; for example, it is now realised that the histological spectrum of hyalinising clear cell carcinoma includes intracellular mucin in over half of cases, as well as tumours with only scanty clear cells. In a separate development, it is now proposed that salivary duct carcinoma can be subdivided along molecular lines, in ways analogous to breast cancer, suggesting new therapeutic prospects in an otherwise highly aggressive malignancy.  相似文献   
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The gerbil is a rodent considered a good model for studies of prostatic morphophysiology under different experimental conditions. Studies involving castration and steroidal blockers of aged gerbils showed that the glandular epithelium persists after long-term therapy, preventing the organ atrophy. Thus, the objective of this study was to evaluate the phenotypic characteristics and behavior of prostatic epithelial cells that remained after different periods of hormone ablation in aged gerbils. The identification of elements that influenced the survival of this cell type was performed by morphometric, nuclear phenotypes, ultrastructural and immune histochemical analysis. The most significant responses to treatment, by analyzing morphometric features, were observed during the first three time points (day 1, day 3, and day 7), after which there appeared to be an adjustment of the gland to the hormone ablation. All treatments led to changes in the state of chromatin condensation, DNA methylation pattern and phenotypic changes indicated cell senescence. Additionally, an increase in the basal cells seemed to guarantee self-renewal properties to the epithelium. These data indicate that changes occur at many levels, including gene expression and nuclear architecture in the epithelial cells, when aging and steroidal blockade are associated. These aspects are important when considering castration-resistant prostate cancer, a malignant tumor posing difficult therapeutic intervention.  相似文献   
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