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Contains fulltext : 174098.pdf (Publisher’s version ) (Open Access) Ataxia-telangiectasia (AT) is a neurodegenerative disorder characterized by ataxia, telangiectasia, and immunodeficiency. An increased risk of malignancies and respiratory diseases dramatically reduce life expectancy. To better counsel families, develop individual follow-up programs, and select patients for therapeutic trials, more knowledge is needed on factors influencing survival. This retrospective cohort study of 61 AT patients shows that classical AT patients had a shorter survival than variant patients (HR 5.9, 95%CI 2.0-17.7), especially once a malignancy was diagnosed (HR 2.5, 95%CI 1.1-5.5, compared to classical AT patients without malignancy). Patients with the hyper IgM phenotype with hypogammaglobulinemia (AT-HIGM) and patients with an IgG2 deficiency showed decreased survival compared to patients with normal IgG (HR 9.2, 95%CI 3.2-26.5) and patients with normal IgG2 levels (HR 7.8, 95%CI 1.7-36.2), respectively. If high risk treatment trials will become available for AT, those patients with factors indicating the poorest prognosis might be considered for inclusion first.

Translesion DNA synthesis, a process orchestrated by monoubiquitinated PCNA, is critical for DNA damage tolerance. While the ubiquitin-conjugating enzyme RAD6 and ubiquitin ligase RAD18 are known to monoubiquitinate PCNA, how they are regulated by DNA damage is not fully understood. We show that NBS1 (mutated in Nijmegen breakage syndrome) binds to RAD18 after UV irradiation and mediates the recruitment of RAD18 to sites of DNA damage. Disruption of NBS1 abolished RAD18-dependent PCNA ubiquitination and Polη focus formation, leading to elevated UV sensitivity and mutation. Unexpectedly, the RAD18-interacting domain of NBS1, which was mapped to its C terminus, shares structural and functional similarity with the RAD18-interacting domain of RAD6. These domains of NBS1 and RAD6 allow the two proteins to interact with RAD18 homodimers simultaneously and are crucial for Polη-dependent UV tolerance. Thus, in addition to chromosomal break repair, NBS1 plays a key role in translesion DNA synthesis., 放射線の修復蛋白NBS1放によるRAD18を介した損傷乗り越えDNA合成の開始. 京都大学プレスリリース. 2011-09-02.

The purpose of this study is to ascertain possible efficacy and to understand possible mechanisms of action of intramuscular or intravenous immunoglobulin (IVIg) in the treatment of intractable epilepsy, through a review of all identifiable articles on this topic. In 24 studies, none with a placebo controlled design, 368 patients with epilepsy receiving IVIg were identified. Patients' ages ranged from < 1 to 35 years, mean 7.3 years. Female/male ratio was 0.6. All patients were reported to suffer from intractable epilepsy. The average percentage of patients with an IgG2 deficiency was 25%. The total dose of IVIg varied between 0.3 and 6.8 g/kg for a period of 0.15 to 12 months. Whenever reported, adverse effects of IVIg were minimal. None of the studies reported the need of cessation of IVIg administration due to adverse effects. On the average, the mean clinical seizure reduction and the mean EEG improvement were 52% and 45%, respectively. On the average the percentage of patients with complete seizure remission and the percentage of patients with behavioral improvement were 23% and 63%, respectively. Cumulative meta-analysis of the identified articles is not possible due to the lack of controlled studies, the heterogeneity of the available studies, and the possible publication bias of unpublished negative data. Given these pitfalls, this literature study nevertheless allows some conclusions: (i) There is no formal proof of efficacy of IVIg treatment in epilepsy, and the present review underscores the need of controlled clinical trials before firm conclusions concerning efficacy can be drawn. The uncontrolled clinical observations discussed in this 'state-of-the-art' review generate suggestive evidence at best. They suggest that IVIg might be effective in some patients with intractable epilepsy, and may be considered as a safe add-on medication in various types of idiopathic and symptomatic intractable epilepsy. (ii) Review of the literature did not help in explaining intractable epilepsy or the mechanism of action of IVIg, but did permit some inferences that could serve to design future clinical and experimental approaches to IVIg administration in epilepsy.

ATAXIA-TELANGIECTASIA, or the Louis-Bar syndrome, is a recessive autosomal disorder clinically characterized by progressive cerebel lar ataxia, oculocutaneous telangiectasia, immunodef ic iency, and a predisposi t ion to the deve lopment o f neoplasia. Most often pat ients die f rom pu lmona ry insufficiency or cancer in the first two decades of life. A T is one of the classical ch romosome breakage syndromes; the cells of the pat ients usually display an increased f requency of spontaneous chromosome breaks and rear rangements . C h r o m o s o m e 14 abnor malities are especially f requent and very often there is a t andem 14q/14q translocation, a so-called Dq + marker c h r o m o s o m e ; , Recent ly we have detected ano the r chromosomal abnormal i ty which might be especially associated with AT: in three subsequent ly studied patients we did not find D q + markers but typical ch romosome 7 abnormal i t ies .