Cerebral autoregulation is preserved in multiple system atrophy: A transcranial Doppler study.

Patients with multiple system atrophy (MSA) present large changes in blood pressure (BP) due to autonomic disturbances. We analyzed how this change may influence dynamic cerebral autoregulation (DCA). Simultaneous recordings of arterial BP (Finapres) and middle cerebral artery (MCA) blood flow velocity (BFV) (transcranial Doppler) were performed in 10 patients with MSA (61 +/- 12 yr of age) and 12 healthy volunteers (61 +/- 11 yr of age): cerebral BFV response to oscillations in mean BP was studied in the supine position by cross-spectral analysis of mean BP and mean MCA BFV. The DCA was also studied during the decrease in BP the first seconds when standing up from a sitting position by the assessment of the cerebrovascular resistance index (CR; mean BP/mean MCA BFV ratio). The MCA BFV/BP cross-spectral analysis showed a phase for the mid-frequency band (0.07-0.2 Hz) significantly larger in MSA, suggesting more active autoregulation in response to larger changes in BP. Changes in CR reflecting the rate of autoregulation, when standing did not differ between the two groups. These data suggest that dynamic cerebral autoregulation is preserved in MSA.     

促血小板生成素对预测脑瘫高危儿的意义

目的探讨缺氧缺血性脑病(hypoxia-ischem ia encephalopathy,H IE)胎儿和H IE新生儿血清中促血小板生成素(Thrombopoietin,TPO)水平与脑损伤的关系,为脑瘫(cerebral palsy,CP)高危儿人群进行早期干预提供监测手段。方法收集23例H IE胎儿和34例H IE新生儿血清以及25例正常胎儿和30例正常新生儿血清,34例H IE新生儿包括11例轻度H IE,8例中度H IE和15例重度H IE。采用双抗体夹心ABC-ELISA法检测H IE胎儿组和轻、中、重H IE新生儿组血清中TPO的水平,并与正常胎儿组和正常新生儿组比较。结果H IE胎儿组和H IE新生儿组TPO分别高于正常胎儿组和正常新生儿组(分别P<0.01,P<0.01),重度H IE组TPO低于轻度H IE组(P<0.05)。结论血清TPO水平与H IE所致脑损伤严重程度有关。脐血TPO检测可为脑瘫高危儿人群进行早期干预提供监测手段。     

Pharmacokinetic profile of tamsulosin OCAS

The tamsulosin oral‐controlled absorption system (OCAS®) is a new tablet formulation of the α₁‐adrenoceptor (α₁‐AR) antagonist tamsulosin, which is used for treating lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH). The tablet uses the OCAS technology, which was specifically designed to give a more continuous 24‐h release of tamsulosin, resulting in a more consistent and continuous 24‐h plasma concentration, a lower maximum plasma concentration (C_max) and an independence of pharmacokinetics (PKs) on food intake. It was expected that the improved PK profile would translate into a better control of day‐ and night‐time symptoms of BPH and a lower risk of adverse events. Phase I PK studies showed that tamsulosin OCAS indeed has a flattened PK profile with a lower C_max and a more stable and consistent 24‐h concentration of tamsulosin, independent of food intake, compared to conventional tamsulosin. A study combining γ‐scintigraphy and PK analysis of blood samples confirmed that the improved PK profile of tamsulosin OCAS is attributed to the tablet being consistently and continuously released throughout the entire gastrointestinal tract, including the colon.     

急性肺栓塞时心肌血流灌注的变化

目的观察急性肺栓塞（APE）后冠状动脉血流量及心脏肌钙蛋白T（cTnT）与肌红蛋白（Mb）含量变化，探讨心肌血流灌注在急性肺栓塞继发心肌损伤机制中的作用。方法通过介入方法经导管注入自体血栓选择性栓塞肺动脉，建立不同栓塞面积的急性肺栓塞动物模型。监测栓前、栓后5、30min，1、2h冠状动脉血流量变化及栓后4h血清cTnT与Mb含量。结果急性肺栓塞后血清cTnT与Mb含量升高。急性肺栓塞导致冠状动脉血流量显著下降，肺血管栓塞后15～30min降至最低值，30min后趋于平稳。右冠血流量下降程度与肺栓塞面积有显著相关性。结论冠状动脉血流量减少及血清心肌结构蛋白含量升高为急性肺栓塞继发心肌缺血改变提供了直接证据。急性心肌缺血严重影响急性肺栓塞的预后。     

Diagnostic accuracy of the Retinal Thickness Analyser: differentiation between normal eyes and eyes with glaucoma or macular pathologies

Background The Retinal Thickness Analyser (RTA) is intended to detect glaucomatous changes as well as macular pathologies at the posterior pole. We determined the diagnostic accuracy for eyes with manifest glaucoma or macular diseases.Methods We examined 71 eyes with long-term, established eye conditions. Included were 28 eyes with glaucoma, 21 with different macular diseases and 22 normal eyes. All examinations were evaluated in a blind-test by RTA experts without any clinical information on the patients. After comparison of the RTA interpretation with the clinical diagnosis, we determined sensitivity, specificity, positive and negative predictive values.Results Of 71 examinations, 15 (21%) were not interpretable. If these results are excluded, the following diagnostic accuracy values were calculated for glaucoma and macular disorders respectively: sensitivity 75 and 59%, specificity 55 and 97%, positive predictive value 48 and 90% and negative predictive value 80 and 84%. These values were not significantly different when both eyes of each patient were included in the final analysis (n=133).Conclusion The diagnostic values of the RTA determined in this case control study were not satisfactory. However, no clinical information was used in the assessment. The extent to which additional clinical information increases the diagnostic value remains to be determined.     

三维骨建模在全膝关节置换术中韧带平衡的作用

目的探讨以三维骨建模为基础、无需影像的计算机辅助系统在人工全膝关节置换术(totalknee arthroplasty,TKA)中韧带平衡的作用。方法2002年11月～2003年6月,采用后稳定型人工全膝关节,在Ceravision无需影像资料的三维骨建模系统导航监控下,辅助完成TKA21例。男5例,女16例,年龄64～79岁,平均72.4岁。其中2例既往行胫骨近端截骨术,1例行股骨远端截骨术。14例膝内翻,7例膝外翻。术前下肢全长X线正位片测量,内翻13°～外翻13°,平均2.36°;膝关节X线正位片测量,应力下内翻平均8.47°(内翻2°～内翻20°),应力下外翻平均3.63°(内翻7°～外翻12°)。结果术中导航系统测量,额面内翻12°～外翻10°,平均3.33°,与术前比较差异有统计学意义(P<0.05);额面应力下内翻平均6.47°(内翻0°～内翻24°),应力下外翻平均4.32°(内翻8°～外翻15°),与术前比较差异有统计学意义(P<0.05)。术毕导航系统测得膝内外翻平均0.175°(内翻2°～外翻3°),而术后下肢全长X线正位片测量平均0.3°(内翻3.5°～外翻1.5°),二者差异无统计学意义(P>0.05)。术后3个月关节活动度为105～130°,平均115°,膝关节额面松弛度0.2～0.5cm,平均0.27cm。人工膝关节胫、股骨假体取得满意的对位置入和韧带平衡,无关节失稳和髌骨脱位等并发症发生。结论以三维骨建模为基础、无需影像的Ceravision系统,具有三维立体定位、优化截骨,并通过旋转对位和韧带松解获得伸屈膝关节等距间隙与韧带平衡稳定的作用,近期临床疗效满意,可在TKA中常规使用。     

Primary angiitis of the central nervous system: MRI features and clinical presentation

We report the MRI features in a series of four patients with primary angiitis of the central nervous system (PACNS). Based on MRI features, clinical presentation, paraclinical investigations and laboratory tests, including cerebrospinal fluid (CSF) analysis, various differentials were considered. In two patients with MRI findings of cortical, subcortical and deep white matter lesions, lack of mass effect, focal areas of bleed and heterogeneous parenchymal, leptomeningeal or pial enhancement and a normal magnetic resonance angiography, a differential diagnosis of primary angiitis of the CNS was also considered. In all patients, an open brain biopsy was advised to establish a definitive diagnosis of PACNS. Here, we briefly discuss the MRI features, correlation with clinical presentation and paraclinical parameters for the diagnosis of this entity. We also briefly review the literature.     

Freezing of gait in postmortem-confirmed atypical parkinsonism.

The frequency and pathophysiology of freezing of gait (FoG) in atypical parkinsonism is unknown. We analysed the frequency of FoG in postmortem-confirmed atypical parkinsonian disorders (APD) comprising corticobasal degeneration (CBD), dementia with Lewy bodies (DLB), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP). Sixty-six patients with pathologically confirmed APD (CBD, n = 13; DLB, n = 14; MSA, n = 15; PSP, n = 24) formed the basis for a multicenter clinicopathological study. Clinical features at first and last clinical visit were abstracted from patient records on standardized forms following strict instructions. At the first visit (median 36 months after symptom onset), 24% of APD had FoG (CBD, 8%; DLB, 21%; PSP, 25%; MSA, 40%). Logistic regression analysis showed a significant association of FoG and urinary incontinence (P = 0.04) at first visit. At last visit, 47% of APD had FoG (CBD, 25%; PSP, 53%; DLB, 54%; MSA, 54%). Clinicopathological correlation based on routine postmortem examination failed to identify a consistent neuropathological substrate of FoG. This study demonstrates that (1) FoG is common in APD, and (2) urinary incontinence is significantly associated with FoG in these disorders. Whether FoG and urinary incontinence share similar neuropathological substrates remains to be determined by future studies.     

Non-invasive Assessment of Coronary Flow Velocity Reserve: A New Method Using Transthoracic Doppler Echocardiography

Coronary flow reserve (CFR) has been used toassess coronary microcirculation and epicardial coro-nary stenoses[1— 3 ] . CFR is defined as the ratio ofcoronary flow under maximal coronary vasodilatationto coronary flow under resting conditions[4 ] .Whenthe cross- sectional area of epicardial coronary arteriesis constant,coronary flow velocity (CFV) ratios areequal to volume flow ratios.The most common method used clinically formeasuring CFVR is intracoronary Doppler flow(ICD) analysis re…     

百年乐与人参黄芪合剂对心血管系统的药理作用比较

百年乐和人参黄芪合剂对心血管系统的作用研究表明:百年乐能加速小鼠肠系膜微循环障碍的恢复,增加离体兔耳血管的流量,使主动脉平滑肌松弛,对抗心肌缺氧,抑制血栓形成,其作用强于人参黄芪合剂。