单蒂横行腹直肌肌皮瓣乳房再造中Ⅳ区皮瓣的取舍

目的探讨单蒂横行腹直肌肌皮瓣乳房再造术中Ⅳ区皮瓣的取舍。方法通过16例实施单蒂横行腹直肌肌皮瓣乳房再造术，术中观察皮瓣的皮色、断面出血颜色，并利用近红外血氧监测仪测定皮瓣各区的组织血氧饱和度，决定Ⅳ区皮瓣的取舍。术后观察指标包括术后并发症及美学效果。结果16例中5例Ⅳ皮瓣的肤色正常、断面出血呈鲜红色而非暗红色、组织血氧饱和度不低于Ⅲ区组织血氧饱和度的95％。在接受了保留Ⅳ区皮瓣的单蒂横行腹直肌肌皮瓣乳房再造术后，再造乳房全部成活，无严重术后并发症，患者对再造乳房均很满意。结论近红外血氧无创检测有助于决定Ⅳ区皮瓣的取舍。有选择地实施保留Ⅳ区皮瓣的单蒂横行腹直肌肌皮瓣乳房再造术，可用于大面积胸壁缺损或乳腺尾叶的修复重建。     

质子磁共振波谱对颞叶癫癎的诊断价值

目的:评价磁共振质子波谱(H MRS)对颞叶癫癎的诊断价值.方法:对20例健康人和18例颞叶癫癎病人进行1H MRS采集,并定量分析了癫痫病人的N-乙酰天门冬氨酸(NAA)、肌酸(Cr)和胆碱复合物(Cho)等代谢产物的变化.结果:癫癎病人致癫灶NAA峰以及NAA/(Cho cr)、NAA/Cr和NAA/Cho比值低于病灶对侧,亦低于健康对照组.正常对照组NAA/(Cho Cr)值平均为0.78,双侧差别小于0.07.我们以NAA/(Cho Cr)值＜0.68和双侧NAA/(Cho Cr)比值的差别＞0.07为判断标准,18例颞叶癫癎病人中,16例为单侧MRS异常,2例为双侧异常.结论:质子磁共振波谱能无创性探测脑组织内生化及代谢改变,是诊断颞叶癫癎的有效手段之一.     

Chemical shift differences between free and Fab-bound peptide correlate with a two-stage selection of peptide sequences from a random phage display library to delineate critical and non-critical residues for antibody recognition

Epitope libraries provide a method to identify peptide ligands for antibodies, receptors or other binding proteins. As such, they provide a powerful tool to rapidly identify lead ligands in the drug discovery process. In an attempt to correlate structural information with the results from peptide screening, we have used NMR spectroscopy of peptide/antibody complexes to demonstrate that core residues identified through a two-stage selection process undergo a larger structural change upon binding antibody than do positions in the peptide amenable to a variety of side chains. The model system used was the M2 monoclonal antibody/Flag? octapeptide epitope system. We have analyzed two peptides: Ac-Asp-Tyr-Lys-Leu-Gly-Asp-Asp-Leu-NH₂ (peptide l), which contains several non-core positions randomized, and Ac-Asp-Tyr-Lys-Asp-Asp-Asp-Asp-Leu-NH₂ (peptide 2), which closely corresponds to the original Flag? sequence. Enrichment of the peptides with ¹⁵N facilitated the investigation by permitting spectral editing of the peptide resonances in the presence of antibody. For peptide 1 the absolute shifts for the free vs. Fab-bound peptide were found to be largest for the amide groups of Asp-1 and Asp-6, in agreement with classification of these residues as critical by the phage display library selection process. For peptide 2 the largest absolute shifts were observed for Asp-1 and Asp-4, with the other aspartic acid residues also showing significant but smaller changes. © Munksgaard 1995.     

Evidence of an abnormal intramuscular component of fatigue in multiple sclerosis

The goals of this study were to investigate muscle fatigue in patients with multiple sclerosis (MS), and to determine the relationships between muscle fatigue, clinical status, and perceived fatigue. The fatigability of the anterior tibial muscle was quantitated in patients and controls during 9 min of intermittent stimulation (used to eliminate central sources of muscle fatigue). During exercise, the decline in tetanic force, phosphocreatine, and intracellular pH was greater in patients than in controls. The compound muscle action potential amplitude did not decrease during exercise, indicating that there was no failure of neuromuscular transmission during fatigue. Thus, the excessive fatigue in MS developed from sources beyond the muscle membrane. Following exercise, the recovery of tetanic force was delayed in patients (a pattern that suggests abnormal excitation–contraction coupling), whereas the recovery of metabolites was complete in both groups. Muscular fatigue was correlated with clinical disability but not with perceived fatigue. These results suggests that fatigue in MS has both central (perception, upper motor neuron dysfunction) and peripheral (impaired metabolism and excitation–contraction coupling) components.© 1995 John Wiley &Sons, Inc.     

Highly resolved in vivo 1H NMR spectroscopy of the mouse brain at 9.4 T.

An efficient shim system and an optimized localization sequence were used to measure in vivo 1H NMR spectra from cerebral cortex, hippocampus, striatum, and cerebellum of C57BL/6 mice at 9.4 T. The combination of automatic first- and second-order shimming (FASTMAP) with strong custom-designed second-order shim coils (shim strength up to 0.04 mT/cm2) was crucial to achieve high spectral resolution (water line width of 11-14 Hz). Requirements for second-order shim strengths to compensate field inhomogeneities in the mouse brain at 9.4 T were assessed. The achieved spectral quality (resolution, S/N, water suppression, localization performance) allowed reliable quantification of 16 brain metabolites (LCModel analysis) from 5-10-microL brain volumes. Significant regional differences (up to 2-fold, P < 0.05) were found for all quantified metabolites but Asp, Glc, and Gln. In contrast, 1H NMR spectra measured from the striatum of C57BL/6, CBA, and CBA/BL6 mice revealed only small (<13%, P < 0.05) interstrain differences in Gln, Glu, Ins, Lac, NAAG, and PE. It is concluded that 1H NMR spectroscopy at 9.4 T can provide precise biochemical information from distinct regions of the mouse brain noninvasively that can be used for monitoring of disease progression and treatment as well as phenotyping in transgenic mice models.     

Mid-infrared spectroscopy on skin using a silver halide fibre probe in vivo

Background/aim: Mid-infrared spectroscopy is a versatile method for in vivo investigation of skin after topical treatment with skin care products.
Methods: FTIR-spectrometer (Bruker Optics) with a flexible silver halide fibre probe (Infrared Fiber Sensors).
Results: Absorbance spectra from 700 to 3000 cm⁻¹ have been recorded to gain information about proteins (amide-I and amide-II vibrations at 1650 and 1550 cm⁻¹), esters (1740 cm⁻¹), carboxylic acid (1710 cm⁻¹), polyalcohols (1050 cm⁻¹) and hydrocarbons (CH _n vibrations at 2800–3000 cm⁻¹).
Conclusions: Using the particular light guide, we were able to measure for the first time the effects of lip care products on lips directly. Furthermore, water binding and glycerol content of the skin could be determined simultaneously, as well as the replenishment of lipids by lipid-enriched bath oil.     

质子磁共振波谱对创伤后应激障碍患者海马神经元异常的诊断价值

目的 探讨质子磁共振波谱（1HMRS）在诊断创伤后应激障碍（post traumatic stress disorder，PTSD）患者海马神经元异常中的价值。方法 对19例PTSD患者及19例健康对照组行常规MRI和1HMRS检查。结果 PTSD患者MRI检查未出现信号的异常。19例患者两侧海马均显示NAA／Cr明显减低，与健康对照组相比，差异有统计学意义（P〈0．01）；而患者两侧海马的Cho／Cr与健康对照组相比，差异无统计学意义（P〉0．05）。结论 1HMRS揭示了PTSD时海马存在着神经元的丢失或功能紊乱，而这些改变是构成PTSD的神经生物学基础之一。     

Calcium pyrophosphate dihydrate deposition disease: morphological and microanalytical features

The light microscopic and polarization appearances of calcium pyrophosphate dihydrate crystal deposits in tissues are reviewed. In routine sections haematoxylinophilic crystalline deposits with a feathery or brush-like pattern are typical of calcium pyrophosphate dihydrate. Short rhomboidal crystals showing positive birefringence are seen on polarization; X-ray microanalytical and infrared spectroscopic data support the specificity of these appearances. The appearances of the crystal deposits in decalcified specimens are also described. We include six cases of calcium pyrophosphate dihydrate deposition within periarticular bone; to the best of our knowledge this has not previously been described.     

二乙基二硫代氨基甲酸钠对沙土鼠脑缺血再灌注损伤的影响

沙土鼠脑缺血60min后,脑组织氧自由基和MDA含量无明显升高,而Mn-SOD的活性下降。缺血60min再灌注5min时,氧自由基显著升高。再灌注30min时,MDA的生成显著增多,Mn-SOD和Cu,Zn-SOD活性显著降低。缺血前15 min,iv DTC对缺血再灌注脑组织中氧自由基和MDA升高有显著抑制作用,对Mn-SOD活性有显著保护作用,且呈剂量依赖关系。     

Localized proton spectroscopy of inoperable brain gliomas. Response to radiation therapy

Within vivo 1H-MRS resonances of several metabolites were simultaneously measured in cerebral gliomas and adjacent normal brain. 15 patients with inoperable brain gliomas all histologically verified were monitored with 1H-MRS and MRI before and after radiotherapy. 11 patients were evaluable. 1H-MRS technique evolved from single volume measurements to one dimensional and two dimensional 1H spectroscopic imaging. In all patients N-acetyl-aspartate signals were decreased in tumour areas compared to the normal brain hemisphere. No recovery was seen after radiotherapy. Choline signals were increased in tumour margins of high grade gliomas and more diffusely in low grade gliomas. In 5 patients the choline resonance decreased after radiotherapy, accompanied by a shrinkage of tumour diameter on MRI. Lactate signals were present in high grade and unspecified astrocytomas and absent in most low grade gliomas. In 3 patients the lactate signal disappeared after radiotherapy. These observations indicate the feasibility of 1H-MRS in monitoring metabolic responses on radiotherapy of brain gliomas.