Participation in sports by children and adolescents with chronic kidney disease

Judging a person's ability to engage in competitive sports is the task of the sports physician. However, in the presence of chronic kidney disease (CKD) or urinary abnormalities such as hematuria or microproteinuria, or in the event of Cakut-type congenital abnormalities a second, qualified opinion by a nephrologist may be needed. A group of pediatric nephrologists belonging to the Italian Society of Pediatric Nephrology were asked to fill in a questionnaire regarding their attitude towards noncompetitive sports and their opinion on whether it is appropriate for them to express their judgment on the suitability/unsuitability of competitive sports activities in children and adolescents with CKD. Regarding noncompetitive sports the nephrologists' attitude was mostly positive, with the only exception of severe CKD. There were some reservations regarding unilateral renal agenesis and kidney transplant recipients. The situation with regard to competitive sports is more complex, as the expression of a favorable opinion often depends on the outcome of a series of instrumental examinations. There are no guidelines and no evidence-based positions on this issue. In order to make the opinions more uniform, the assessment methods should be standardized so that young people with CKD will be able to benefit from sports activities not only in terms of physical performance but also socialization and personal well-being.     

Psychometric properties of self-administered Lequesne Algofunctional Indexes in patients with hip and knee osteoarthritis: an evaluation using classical test theory and Rasch analysis

The aim of this study is to perform a psychometric analysis of the Lequesne Algofunctional Indexes (LAI) for the severity of osteoarthritis (OA) of the hip (LAI-hip) and knee (LAI-knee), using classical test theory (CTT) and Rasch analysis. Questionnaires were completed by 1,214 patients with symptomatic OA of the knee (n = 697) and hip (n = 517). Internal consistency was evaluated using Cronbach’s alpha and an item-to-total correlation. Dimensionality was investigated with a factor analysis. Raw scores underwent Rasch analysis. Cronbach’s alpha was 0.84 for LAI-hip and 0.82 for LAI-knee. LAI-hip resulted in unidimensionality according to the factor analysis, while LAI-knee supported both a single and a two-factor solution (items 1–6b and 7–10, respectively). At Rasch analysis, the rating categories of item ‘maximum distance walked’ did not comply with the criteria for category functioning in either LAI-hip or LAI-knee. A test of the residual correlation showed item dependency in both LAI-hip and LAI-knee. Misfitting items were present in both the scales. According to both CTT and Rasch analysis, in our two samples representing a wide spectrum of both hip and knee OA severity the LAI-hip and LAI-knee showed a series of drawbacks, which rendered both questionnaires inadequate in relation to their metric properties and severely limit their ability to perform, as a composite measure, in line with the main aims of their developers.     

Chest pain caused by myocardial ischemia or not: sometimes the old handgrip test can solve the dilemma

We describe the case of a patient with typical chest pain but negative maximal bicycle exercise-electrocardiogram test and for whom significant coronary artery disease was hypothesized by a positive handgrip exercise test and demonstrated by coronary angiography. Despite negative exercise stress test, handgrip as well as other provocative tests have to be considered when the pretest probability of coronary artery disease is intermediate and the symptoms are typical for angina.     

Janus kinase (JAK) 2 V617F mutation as the cause of primary thrombocythemia in acromegaly with severe visceromegaly and divergence between growth hormone and insulin-like growth factor-1 concentrations during the follow-up: causal or casual association?

ObjectiveAn increased prevalence of hematological abnormalities is reported in acromegaly, but to date no reports about the presence of the Janus Kinase (JAK) 2 mutation in acromegalic patients have been described.DesignWe report the complex clinical presentation of the unique case, never described, of acromegaly due to GH-secreting pituitary adenoma associated with JAK2 V617F mutation.ResultsThe patient shows primary thrombocythemia and myelofibrosis, due to JAK2 V617F mutation, severe visceromegaly and a peculiar clinical course of the disease characterized by discrepant values of GH and IGF-1 during somatostatin analog (SA) treatment despite a significant reduction in pituitary adenoma size and therapeutic resistance both to SA and pegvisomant.ConclusionsThe presence of JAK2 V617F mutation is a cause of primary thrombocythemia and myelofibrosis in acromegaly. In this patient, a peculiar clinical course of acromegaly was observed, with the difficulty in controlling the disease. More data, on a larger cohort of patients, could clarify whether JAK2 V617F mutation has a serious impact on the clinical features and course of acromegaly.     

猪精子细胞中胰岛素诱导产生的一氧化氮自由基促进精子获能

近期,胰岛素被证实具有诱导猪精子获能的能力。在不同的哺乳动物中,精子获能被认为与一氧化氮信号通路相关;因此,本研究使用荧光激活细胞分选技术探究经胰岛素处理的猪精子中一氧化氮水平。在同一样本中,用金霉素染色、蛋白质酪氨酸磷酸化模式和顶体状态来评估精子获能。结果显示经胰岛素处理的精子内一氧化氮水平及三种评价精子获能的指标均有显著提高;相反,用一氧化氮合成酶抑制剂（N-硝基-L-精氨酸甲酯）或抗胰岛素受体β抗体预处理的精子中胰岛素相关的作用全被逆转。这些结果表明胰岛素具有增强猪精子细胞内一氧化氮浓聚的能力并且提示胰岛素可能通过一氧化氮促进精子获能。