Longitudinal changes in haemoglobin mass and <Emphasis Type="Italic">V</Emphasis>O<Subscript>2max</Subscript> in adolescents

This study assessed the relationship between haemoglobin mass (Hb_mass) and maximum oxygen consumption (VO_2max) in adolescents over 1 year. Twenty-three subjects (11–15 years) participated; 12 undertook ~12 months of cycle training (cyclists) and 11 were sedentary (controls). Hb_mass and VO_2max were measured approximately every 3 months. At baseline there was a high correlation (r = 0.82, P < 0.0001) between relative VO_2max (ml kg⁻¹ min⁻¹) and relative Hb_mass (g kg⁻¹). During 12 months there was a significant increase in relative VO_2max of the cyclists but not the controls; however, there was no corresponding increase in relative Hb_mass of either group. The correlation between percent changes in relative VO_2max and relative Hb_mass was not significant for cyclists (r = 0.31, P = 0.33) or controls (r = 0.42, P = 0.19). Training does not increase relative Hb_mass in adolescents consistent with a strong hereditary role for Hb_mass and VO_2max. Hb_mass may be used to identify adolescents who have a high VO_2max.     

Lack of pathogenic mutations in SOS1 gene in phenytoin-induced gingival overgrowth patients

ObjectiveGingival overgrowth is a side effect associated with some distinct classes of drugs, such as anticonvulsants, immunosuppressants, and calcium channel blockers. One of the main drugs associated with gingival overgrowth is the antiepileptic phenytoin, which affects gingival tissues by altering extracellular matrix metabolism. It has been shown that mutation of human SOS1 gene is responsible for a rare hereditary gingival fibromatosis type 1, a benign gingival overgrowth. The aim of the present study is to evaluate the possible contribution of SOS1 mutation to gingival overgrowth-related phenotype.DesignWe selected and screened for mutations a group of 24 epileptic patients who experienced significant gingival overgrowth following phenytoin therapy. Mutation scanning was carried out by denaturing high-performance liquid chromatography analysis of the entire coding region of the SOS1 gene. Novel identified variants were analyzed in-silico by using Alamut Visual mutation interpretation software, and comparison with normal control group was done.ResultsMutation scanning of the entire coding sequence of SOS1 gene identified seven intronic variants and one new exonic substitution (c.138G > A). The seven common intronic variants were not considered to be of pathogenic importance. The exonic substitution c.138G > A was found to be absent in 100 ethnically matched normal control chromosomes, but was not expected to have functional significance based on prediction bioinformatics tools.ConclusionsThis study represents the first mutation analysis of the SOS1 gene in phenytoin-induced gingival overgrowth epileptic patients. Present results suggest that obvious pathogenic mutations in the SOS1 gene do not represent a common mechanism underlying phenytoin-induced gingival overgrowth in epileptic patients; other mechanisms are likely to be involved in the pathogenesis of this drug-induced phenotype.     

蜗后性听力减退29例病因分析

目的　探讨蜗后性低频听力减退的发病原因。方法　复习 1988～ 2 0 0 2年 2 9例原因明确的蜗后性低频听力减退患者的临床特点和听力学检查结果。结果　头部外伤、听神经瘤、周围神经病、遗传性聋、多发性硬化和脑干疾病均可表现为蜗后性低频听力减退 ,其共同的特点是 :低频听力减退 ,诱发性耳声发射正常或至少在部分频率正常 ,不受对侧噪声抑制 ,引不出镫骨肌反射 ,听性脑干反应 (auditorybrainstemresponse ,ABR)异常。结论　以耳声发射正常和ABR异常为主要特征的听功能障碍是一组症状群 ,可为不同病因引起的听神经和 (或 )听性脑干病变的表现 ,建议对这一组听力学表现称之为蜗后性低频听力减退。     

Management of patients with hereditary angio-oedema in dental,oral, and maxillofacial surgery: a review

Hereditary angio-oedema (HEA) is an autosomal dominant, life-threatening genetic disorder that is caused by insufficiency or dysfunction of the C1 esterase inhibitor that develops coincidentally with recurrent oedema in the skin, internal organs, and upper respiratory tract. Increased production of bradykinin secondary to increased plasma kallikrein activity is the primary cause of attacks. Dental procedures cause emotional stress and mechanical trauma and may also initiate attacks. The most feared complication is asphyxiation as a result of laryngeal oedema. Cases that resulted in death after tooth extraction have been reported, so dentists and oral and maxillofacial surgeons should take maximum care in the treatment of patients with HAO, consult with the patient’s doctor, and ensure that prophylaxis is given before the procedure. They should work as atraumatically as possible and use procedures to minimise stress. In the event of an attack of HAO, despite all the correct measures having been taken, the procedure should be terminated immediately and treatment of the attack started as soon as possible. The first drugs for the treatment of acute attacks are C1-INH (C1 inhibitor), ecallantide, or icatibant.     

“When information is not enough”: A model for understanding BRCA-positive previvors’ information needs regarding hereditary breast and ovarian cancer risk

ObjectiveTo investigate BRCA-positive, unaffected patients’ – referred to as previvors – information needs after testing positive for a deleterious BRCA genetic mutation.Methods25 qualitative interviews were conducted with previvors. Data were analyzed using the constant comparison method of grounded theory.ResultsAnalysis revealed a theoretical model of previvors’ information needs related to the stage of their health journey. Specifically, a four-stage model was developed based on the data: (1) pre-testing information needs, (2) post-testing information needs, (3) pre-management information needs, and (4) post-management information needs. Two recurring dimensions of desired knowledge also emerged within the stages—personal/social knowledge and medical knowledge.ConclusionsWhile previvors may be genetically predisposed to develop cancer, they have not been diagnosed with cancer, and therefore have different information needs than cancer patients and cancer survivors.Practice ImplicationsThis model can serve as a framework for assisting healthcare providers in meeting the specific information needs of cancer previvors.     

Syndrome in question

Ross syndrome is a rare disease characterized by peripheral nervous systemdysautonomia with selective degeneration of cholinergic fibers. It is composedby the triad of unilateral or bilateral segmental anhidrosis, deep hyporeflexiaand Holmes-Adie''s tonic pupil. The presence of compensatory sweating isfrequent, usually the symptom that most afflicts patients. The aspects of thesyndrome are put to discussion due to the case of a male patient, caucasian, 47years old, with clinical onset of 25 years.