Remission of paroxysmal atrial fibrillation with iron reduction in haemophilia A

Summary. Two male first cousins with mild haemophilia A had baseline factor VIII levels of 12–15% and experienced bleeding requiring coagulation factor infusion therapy with trauma and surgical procedures. Both the patients with haemophilia A also had electrocardiographically documented symptomatic paroxysmal atrial fibrillation (PAF) for several years that had become resistant to pharmacological suppression. Radiofrequency ablation was considered in both the cases but deferred considering refusal of consent by the patients to undergo the procedure. Remission of arrhythmias has been reported in patients with iron‐overload syndromes. Body iron stores assessed by serum ferritin levels were elevated in both men but neither had the C282Y or H63D genes for haemochromatosis. Calibrated reduction of iron stores by serial phlebotomy, avoiding iron deficiency, was followed by remission of symptomatic PAF in both cases. Iron reduction may be an effective treatment for arrhythmias apart from the classic iron‐overload syndromes and deserves further study particularly in patients with bleeding disorders who might be at risk for arrhythmias and other diseases of ageing.     

Leukaemic T Cells from Patients with Chronic Lymphocytic Leukaemia of T-Cell Origin Respond to Staphylococcus aureus Enterotoxin Superantigens

We investigated the in vitro responsiveness of peripheral blood lymphocytes from two patients with T-cell chronic lymphocytic leukaemia (T-CLL) to Staphylococcus aureus enterotoxin (SE) superantigens. T-cell receptor (TcR) αβ(Vβ 7.1)-expressing CD4⁺ leukaemic T cells from patient HE (white blood cell count 480,000/μl) proliferated in response to SEA and, only at 1000-fold higher concentrations, to SEB, SED, and SEE. CD4⁺ CD8⁺ TcRαβ (Vβ 12.1)-expressing leukaemic T cells from patient KO (white blood cell count 120,000/μl) were activated by SEB but not by the other tested SEs. In both instances, the activation of leukaemic T cells by SE was dependent on the presence of HLA-DR⁺ cells. Southern blot analysis of TcRβ gene rearrangement confirmed that the proliferating cells were derived from the leukaemic T-cell clone and not from contaminating normal T cells. These data indicate that leukaemic T cells from patients with T-CLL exert a clonally variable responsiveness to SE superantigens. We conclude that recognition of specific antigen and subsequent signal transduction can be initiated via the TcR of leukaemic T-CLL cells.     

A Pro51Ser mutation in the COCH gene is associated with late onset autosomal dominant progressive sensorineural hearing loss with vestibular defects

We analysed a Dutch family with autosomal dominant non-syndromic progressive sensorineural hearing loss and mapped the underlying gene defect by genetic linkage analysis to a 11.0 cM region overlapping the DFNA9 interval on chromosome 14q12-q13. Clinically, the Dutch family differs from the original DFNA9 family by a later age at onset and a more clearly established vestibular impairment. A gene that is highly and specifically expressed in the human fetal cochlea and vestibule, COCH (previously described as Coch5B2 ), was mapped to the DFNA9 critical region. Sequence analysis revealed a 208C-->T mutation in the COCH gene, resulting in a Pro51Ser substitution in the predicted protein in all affected individuals of the family but not in unaffected family members and 200 control individuals. The same mutation was also identified in three apparently unrelated families with a similar phenotype, suggesting the presence of a Dutch founder mutation. The function of COCH is unknown but several characteristics of the protein point to a structural role in the extracellular matrix. The mutant serine at position 51 is situated between cysteines and possibly interferes with proper COCH protein folding or its interaction with extracellular matrix proteins.      

冠状动脉痉挛诱发心律失常的临床特点及治疗效果

目的探讨冠状动脉痉挛（CAS）诱发心律失常的临床特点及治疗效果。方法选择1998年7月至2008年12月期间入住本院的16例CAS患者,CAS的诊断根据病史和症状,结合标准12导联心电图、动态心电图及冠状动脉造影等检查确定。结果16例患者CAS发作时伴有心绞痛和心电图ST段抬高。全部病例均合并缓慢性和／或快速性心律失常,其中缓慢性心律失常6例,二、三度房室阻滞5例,窦性静止1例;快速性心律失常12例,其中持续性室性心动过速（室速）和心室颤动（室颤）5例,非持续性室速5例,室性早搏2例。冠状动脉造影显示,4例冠状动脉完全正常,4例冠状动脉狭窄等于或超过50％,其余8例冠状动脉狭窄均≤45％。全部病例均接受了大剂量钙拮抗剂和硝酸酯类的联合抗血管痉挛治疗。冠状动脉有明显狭窄的4例患者接受了介入治疗。除1例患者死亡外,其余患者平均随访（52．3±18．9）个月,无心绞痛及晕厥发作。结论有或无冠状动脉病变的CAS均可诱发缓慢性和／或快速性室性心律失常;除针对冠状动脉基础病变治疗外,地尔硫革和硝酸酯类等联合抗痉挛治疗是主要的治疗措施。     

The clinical picture of ectasia of the intracerebral arteries

Thirty-one patients with ectasia of intracranial arteries were studied. The carotid system was more frequently involved than the vertebrobasilar. The condition is relatively rare and usually occurs with other vascular disease. Ectasia presents with a variety of neurological symptoms, amongst which visual disorders are common. The overall mortality was 52%, but the prognosis was appreciably worse for the vertebrobasilar group, probably because of a higher incidence of compression of surrounding neural structures. Defects in the internal elastic lamina, with or without associated atheroma, are often found in the affected arteries.