GFAP and antibodies against NMDA receptor subunit NR2 as biomarkers for acute cerebrovascular diseases

We studied whether the serum levels of glial fibrillary acidic protein (GFAP) and of antibodies against the N‐methyl‐d ‐aspartate receptor subunit NR2 (NR2 R_NMDA) can discriminate between intracerebral haemorrhage (ICH) and ischaemic stroke (IS) in stroke patients. We prospectively recruited patients with suspected stroke (72 confirmed) and 52 healthy controls. The type of brain lesion (ICH or IS) was established using brain imaging. The levels of GFAP and of antibodies against NR2 R_NMDA were measured in blood samples obtained within 12 hrs after stroke onset and 24, 48 and 72 hrs and 1 and 2 weeks later using ELISA immunoassay. Improvement in diagnostic performance was assessed in logistic regression models designed to predict the diagnosis and the type of stroke. GFAP peaks early during haemorrhagic brain lesions (at significantly higher levels), and late in ischaemic events, whereas antibodies against NR2 R_NMDA have significantly higher levels during IS at all time‐points. Neither of the two biomarkers used on its own could sufficiently discriminate patients, but when they are used in combination they can differentiate at 12 hrs after stroke, between ischaemic and haemorrhagic stroke with a sensitivity and specificity of 94% and 91%, respectively.     

Plasma desmoplakin I biomarker of vascular recurrence after ischemic stroke

Stroke patients have a high risk of vascular recurrence. Biomarkers related to vascular recurrence, however, remain to be identified. The aim of the study was to identify, through proteomic analysis, plasma biomarkers associated with vascular recurrence within one year after the first ischemic stroke. This is a substudy (n = 134) of a large prospective multicenter study of post-stroke patients with an ischemic stroke. Plasma samples were obtained at inclusion. Among the identified proteins, only plasma levels of desmoplakin I were associated with protection against a new vascular event (Odds ratio: 0.64; 95% CI: 0.46-0.89; p = 0.009) after adjustment for hypercholesterolemia, statins and previous atherothrombotic stroke subtype. A greater number of patients without vascular recurrence had been treated with statins within three months of the recent ischemic stroke. Only patients who had been taking statins for 3 months after the ischemic stroke and did not suffer vascular recurrence over a follow-up year, have higher levels of desmoplakin I at the time of inclusion (Odds ratio 0.49; 95% CI: 0.28-0.86; p = 0.013). Increased desmoplakin I levels, determined within 1-3 months of the first ischemic stroke, could be a biomarker for statin responsiveness against a new vascular event in post-ischemic stroke patients taking statins early (1-3 months) after the ischemic stroke.     

应用手持激光器建立光化学法脑梗死动物模型

目的应用手持激光器作为光源建立光化学法局灶性脑梗死动物模型。方法将36只SD大鼠随机分为4组,即A组：开骨窗至硬脑膜,不注射玫瑰红,手持激光器照射5rain;B组：开骨窗至硬脑膜,注射玫瑰红,手持激光器照射5min;C组：保留颅骨内板,注射玫瑰红,手持激光器照射5min;D组：开骨窗至硬脑膜,注射玫瑰红,冷光源照射40rain。于术后24、48h对各组大鼠进行神经功能的行为学评分,进行MR扫描,术后48h处死动物,TTC染色测量梗死体积,光镜下观察病理改变,比较各组的模型制作成功率。结果不同方法进行动物模型制作时,24h神经功能的行为学评分有显著性差异,48h后差异消失。头部MR扫描显示,A组未见脑梗死形成,B组、c组全部有脑梗死灶形成,D组仅部分大鼠形成梗死灶,但体积明显较B、C组小,另外C组有2例合并硬膜外血肿。TTC染色A组未见梗死灶形成,B组、C组可见恒定的梗死灶,D组仅部分形成梗死灶。B、C、D组模型制作成功率分别为100％、80％、50％,将B组、C组合并为手持激光器组,与冷光源组（D组）比较,两种方法间有显著性差异（P=0．026）。结论应用手持激光器作为照射光源与冷光源相比,有更高的模型制作成功率。     

Hsp70 Induction and hsp70 Gene polymorphisms as Indicators of acclimatization under hyperthermic conditions

The possibility of using Hsp70 and hsp70 gene polymorphisms as markers of acclimatization was investigated. Volunteers (22) were subjected to an acclimatization regimen and blood analysed for Hsp70 (Hsp72) and hsp70 polymorphisms before and after a heat tolerance test. Physiological parameters denoting acclimatization, or not, were correlated to levels of Hsp70 and combination of hsp70 genes. Only individuals that acclimatized had decreased basal Hsp70 levels and increased ability to induce Hsp70 together with a specific hsp70 genotype combination. We propose that Hsp70 levels (basal vs. induced) with the genotype combination have the potential to be used as markers of acclimatization.     

Facile, alternative route to lubeluzole, its enantiomer, and the racemate

Lubeluzole [(S)-9] has been synthesized by a convergent synthesis, alkylation of N-methyl-N-piperidin-4-yl-1,3-benzothiazol-2-amine (4) with (+)-(R)-1-chloro-3-(3,4-difluorophenoxy)propan-2-ol [(+)-(R)-8] being the key step. Alcohol (+)-(R)-8 was obtained from commercially available (R)-epichlorohydrin [(R)-6], while the thiazole derivative 4 was easily obtained starting from N-protected piperidin-4-one (1) in a three-step procedure. The same method was used in order to obtain both the (R)-stereoisomer of lubeluzole [(R)-9] and its racemate [(RS)-9]. Overall yields ranged from 20% to 35%. The enantiomeric excess values for (S)-9 and (R)-9 were 97% and 94% respectively, as analyzed by chiral HPLC.     

Mesenchymal stem cells as trophic mediators

Adult marrow-derived Mesenchymal Stem Cells (MSCs) are capable of dividing and their progeny are further capable of differentiating into one of several mesenchymal phenotypes such as osteoblasts, chondrocytes, myocytes, marrow stromal cells, tendon-ligament fibroblasts, and adipocytes. In addition, these MSCs secrete a variety of cytokines and growth factors that have both paracrine and autocrine activities. These secreted bioactive factors suppress the local immune system, inhibit fibrosis (scar formation) and apoptosis, enhance angiogenesis, and stimulate mitosis and differentiation of tissue-intrinsic reparative or stem cells. These effects, which are referred to as trophic effects, are distinct from the direct differentiation of MSCs into repair tissue. Several studies which tested the use of MSCs in models of infarct (injured heart), stroke (brain), or meniscus regeneration models are reviewed within the context of MSC-mediated trophic effects in tissue repair.     

A preliminary investigation into tooth care, dental attendance and oral health related quality of life in adult stroke survivors in Tayside, Scotland

Objective: The aim of this study was to investigate patterns of oral care, dental attendance and oral health‐related quality of life among adults who had suffered a stroke. Background: Stroke is the most common cause of adult disability in the UK. Seventy per cent of strokes occur in adults over 65 years of age. A mild stroke may leave little residual disability but in cases of moderate or severe stroke the disability may be significant and may impact on oral health and function. Materials and methods: A cross‐sectional survey was conducted among adults surviving 1 year after stroke, between January and July 2001. A medical screening was carried out which included an assessment of disability and handicap using the modified Rankin scale. A structured interview was conducted to identify normal patterns of oral care and dental attendance and to elicit if since suffering a stroke any changes had occurred or were likely to occur. The Short Form Oral Health Impact Profile (OHIP‐14) was administered prior to an oral examination. Analysis used SPSS 11.0 for Windows. Parametric and nonparametric tests were undertaken (t‐tests and chi‐squared tests with Yates correction where appropriate). Results: Forty‐one adults were recruited into the study comprising 21 female and 20 male. They ranged in age from 50 to 87 years and the mean age was 69 years (SD = 9.8). Forty per cent of participants experienced moderate disability or greater following their stroke. Thirty‐seven per cent had difficulty with tooth cleaning. The most frequently reported problem was being unable to use one hand properly as a result of the stroke. There was a significant association between the degree of disability following stroke and difficulty with tooth cleaning (P = 0.015). Disability as a result of the stroke was cited as the main reason for reported or projected attendance pattern change. The most frequently experienced OHIP‐14 dimension was functional limitation (39%). Conclusion: Individuals who have been left disabled after a stroke may require help with or advice on oral care and information on how to access dental services in a setting appropriate to their disability. Further research is needed to identify the dental needs of adults with stroke and to identify appropriate interventions to meet these needs.     

Influence of transoesophageal echocardiography on therapy and prognosis in young patients with TIA or ischaemic stroke

Objective. To determine the influence of transoesophageal echocardiography (TEE) on therapy and prognosis in patients with cryptogenic transient ischaemic attack (TIA) or ischaemic stroke under the age of 50 years. Methods and results. We evaluated all patients aged 50 and under who were referred to our university hospital for cryptogenic TIA or ischaemic stroke during the period 1 January 1996 to 31 December 2004. All patients underwent both transthoracic echocardiography (TTE) and TEE. Patients with known pre-existent heart disease, such as atrial fibrillation, were excluded. Eighty-three patients with TIA (22) and ischaemic stroke (61) were enrolled. Mean age was 39±8 years (range 18 to 50). In 30% of the patients TEE detected one or more potential cardioembolic source, compared with 10% for TTE (p=0.003). Standard treatment (aspirin 38 mg daily) was changed in 7% of the patients due to the TEE findings. Complete followup was obtained in 93% with an average of 5±3 years. Twelve recurrences occurred; two out of six patients (33%) with therapy change and ten out of 71 (14%) of the patients without therapy change had a recurrent TIA or ischaemic Stroke. Conclusion. In patients with cryptogenic TIA or ischaemic stroke, TEE is superior to TTE in the detection of a potential cardiac source of embolism. However, findings obtained by TEE only influence the already initiated treatment in a small percentage of patients. The recurrence rate both in the group with and without therapy change is high. (Neth Heart J 2009;17:373–7.)     

Predicting order of conformational changes during protein conformational transitions using an interpolated elastic network model

The decryption of sequence of structural events during protein conformational transitions is essential to a detailed understanding of molecular functions ofvarious biological nanomachines. Coarse‐grained models have proven useful by allowing highly efficient simulations of protein conformational dynamics. By combining two coarse‐grained elastic network models constructed based on the beginning and end conformations of a transition, we have developed an interpolated elastic network model to generate a transition pathway between the two protein conformations. For validation, we have predicted the order of local and global conformational changes during key ATP‐driven transitions in three important biological nanomachines (myosin, F₁ ATPase and chaperonin GroEL). We have found that the local conformational change associated with the closing of active site precedes the global conformational change leading to mechanical motions. Our finding is in good agreement with the distribution of intermediate experimental structures, and it supports the importance of local motions at active site to drive or gate various conformational transitions underlying the workings of a diverse range of biological nanomachines. Proteins 2010. © 2010 Wiley‐Liss, Inc.