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81.
We aimed to describe the negative and positive impacts of changes in cancer care delivery due to COVID-19 pandemic for adolescents and young adults (AYAs) in Canada, as well as the correlates of negative impact and their perspectives on optimization of cancer care. We conducted an online, self-administered survey of AYAs with cancer living in Canada between January and February 2021. Multiple logistic regression was used to identify factors associated with a negative impact on cancer care. Of the 805 participants, 173 (21.5%) experienced a negative impact on their cancer care including delays in diagnostic tests (11.9%), cancer treatment (11.4%), and appointments (11.1%). A prior diagnosis of mental or chronic physical health condition, an annual income of <20,000 CAD, ongoing cancer treatment, and province of residence were independently associated with a negative cancer care impact (p-value < 0.05). The majority (n = 767, 95.2%) stated a positive impact of the changes to cancer care delivery, including the implementation of virtual healthcare visits (n = 601, 74.6%). Pandemic-related changes in cancer care delivery have unfavorably and favorably influenced AYAs with cancer. Interventions to support AYAs who are more vulnerable to the adverse effects of the pandemic, and the thoughtful integration of virtual care into cancer care delivery models is essential.  相似文献   
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We describe the case of a patient with known Wegener's Granulomatosis who developed a spontaneous intradural haematoma in the thoracic spine against a background of a recent relapse in her vasculitis. Decompression resulted in a rapid recovery of lower limb function. We propose involvement of the spinal meninges in the systemic vasculitis as the cause of haemorrhage.  相似文献   
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Venous thromboembolism (VTE) is a frequent complication in melanoma patients with brain metastases (BM). The management of these patients is challenging because of the high risk of intracranial hemorrhage (ICH) and the limited data available on the safety of anticoagulation in this scenario. We reviewed the treatments and outcomes among melanoma patients with BM and VTE at our institution to determine the safety of anticoagulation in these patients. A retrospective chart review was performed to identify melanoma patients with BM who were diagnosed with VTE. The clinical characteristics of the BM and the VTE, the treatments given for VTE, subsequent ICH, and overall survival (OS) were determined. The characteristics and outcomes were compared between patients who received systemic anticoagulation and those who did not. A total of 74 evaluable melanoma patients with BM and VTE were identified. Fifty-seven (77%) patients received systemic anticoagulation. There was no significant difference in the number (P=0.40) or the maximum diameter (P=0.55) of brain metastasis between the patients who received anticoagulation and those who did not. Two (4%) patients who received anticoagulation developed ICH, which was not statistically different from the patients who did not receive anticoagulation (0%, P=1.00). There was a trend toward longer OS from VTE among patients who received systemic anticoagulation (median OS: 4.2 vs. 1.2 months, P=0.06). Anticoagulation for VTE did not significantly increase the risk of ICH or decrease OS in patients with melanoma BM. These data support the safety of systemic anticoagulation for VTE in these patients.  相似文献   
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Objective: Oral acetazolamide is a potent medical treatment for pediatric glaucoma, but ophthalmologists may have concerns that it retards weight gain in children and may choose surgical management instead.Design: Retrospective chart review.Participants: Twenty-two well children with glaucoma taking acetazolamide orally for ≥ 3 months.Methods: Abnormal weight gain was determined using downward crossing of 2 percentile lines on growth charts and change in z score for weight using a hierarchical linear model.Results: One patient with Sturge-Weber syndrome and growth failure was excluded when growth hormone deficiency was diagnosed. Two patients crossed 2 lines downward; both showed metabolic acidosis. The trend for the 2 reversed after medication was discontinued. The other 20 tracked steadily on growth curves. Eleven patients (11/22, 50%) showed a decline in z score for weight over the follow-up period, and the remainder showed an increase, for an overall estimate of slope in this sample of 0.01, which was not significant (p = 0.8).Conclusions: Oral acetazolamide may cause poor weight gain in a small subset of children on treatment. Metabolic acidosis may be a mediating factor for growth failure. Our data suggest that acetazolamide does not cause significant weight changes in cases of pediatric glaucoma. Growth parameters should be followed. Growth hormone deficiency should be considered in Sturge-Weber syndrome. Prospective study is needed.  相似文献   
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Betaine homocysteine S-methyltransferase (BHMT) catalyzes the transfer of a methyl group from betaine to homocysteine (Hcy), forming dimethylglycine and methionine. We previously showed that inhibiting BHMT in mice by intraperitoneal injection of S-(α-carboxybutyl)-dl-homocysteine (CBHcy) results in hyperhomocysteinemia. In the present study, CBHcy was fed to rats to determine whether it could be absorbed and cause hyperhomocysteinemia as observed in the intraperitoneal administration of the compound in mice. We hypothesized that dietary administered CBHcy will be absorbed and will result in the inhibition of BHMT and cause hyperhomocysteinemia. Rats were meal-fed every 8 hours an l-amino acid–defined diet either containing or devoid of CBHcy (5 mg per meal) for 3 days. The treatment decreased liver BHMT activity by 90% and had no effect on methionine synthase, methylenetetrahydrofolate reductase, phosphatidylethanolamine N-methyltransferase, and CTP:phosphocholine cytidylyltransferase activities. In contrast, cystathionine β-synthase activity and immunodetectable protein decreased (56% and 26%, respectively) and glycine N-methyltransferase activity increased (52%) in CBHcy-treated rats. Liver S-adenosylmethionine levels decreased by 25% in CBHcy-treated rats, and S-adenosylhomocysteine levels did not change. Furthermore, plasma choline decreased (22%) and plasma betaine increased (15-fold) in CBHcy-treated rats. The treatment had no effect on global DNA and CpG island methylation, liver histology, and plasma markers of liver damage. We conclude that CBHcy-mediated BHMT inhibition causes an elevation in total plasma Hcy that is not normalized by the folate-dependent conversion of Hcy to methionine. Furthermore, metabolic changes caused by BHMT inhibition affect cystathionine β-synthase and glycine N-methyltransferase activities, which further deteriorate plasma Hcy levels.  相似文献   
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The availability of newer technologies for identification and characterization of the human genome has enabled our understanding of the genetic variations in a majority of human diseases. Human genomic sequence varies in less than 1% among the different population group and these differences known as gene polymorphisms are the primary reasons for differences in individuals’ response to various drug therapy. Also understanding the genetic changes may enable implementation of targeted therapy, thus providing for effective treatment strategies and minimizing the adverse side effects. Pharmacogenomics is a recent development in the field of personalized medicine which focuses on the genetic determinants of drug response at the levels of entire human genome. It primarily deals with tailoring of drug therapy for every individual based on their genetic make-up and identifying new target in various diseases for drug therapy. While the application of pharmacogenomics in systemic illness is well researched, its role in oral diseases needs documentation. Identifying specific targets in periodontitis, head and neck cancer, infections and genetic disorders can be beneficial in discovery of new drugs. This editorial provides an overview of basics of pharmacogenomics, its current role in disease management and its potential role in various head and neck diseases.  相似文献   
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