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.     

Effect of prior exercise in Pi/PC ratio and intracellular pH during a standardized exercise. A study on human muscle using [31P]NMR

Seven subjects underwent a standard localized exercise of calf muscles in order to investigate whether the metabolic exercise-induced steady-state, as revealed by the evaluation of inorganic phosphate/phosphocreatine ratio, depends on the conditioning of the muscle just prior to the exercise. The experimental protocols consisted of two separate experiments using first [³¹P]nuclear magnetic resonance spectroscopy and second (on 3 subjects) infrared oxyphotometry to respectively follow variation of energy metabolism and tissular deoxygenation. The exercise consisted of 240 successive plantar flexions (0.5 Hz frequency) against a high load equivalent to SO% of the maximal voluntary contraction. This exercise was accomplished before cold exercise and after warm exercise, a warming-up period bringing to approximately 50% of Vo_2max. The results showed that: (1) steady-state level of phosphate/phosphocreatine and intracellular acidosis was significantly lowered by warming-up; (2) cold and warm exercise steady-state of calculated adenosine diphosphate values were not significantly different; (3) cold exercise rapidly induced a high tissular deoxygenation that is not observed during warm exercise; and (4) time-constant of phosphocreatine resynthesis is lowered after warm exercise but the initial slope of time-evolution is not modified. Parallel experiments also showed that phosphate/phosphocreatine steady-state was not modified in comparison with warm exercise when the same power of exercise was reached by stepwise incrementation of the charge. From these results we postulate that a better tissue oxygenation due to a global or localized warming-up allows to reach the same mechanical performance with a lower decrease of PCr content, owing to a faster adjustment of oxidative metabolism during the transitional period. However the aerobic pathway flux during the steady-state is probably the same before and after the warming-up despite different values of phosphate/phosphocreatine. As a consequence it can be assumed that this ratio is not a good indicator of the rate of muscle oxidative metabolism during the steady-state phase of the exercise.     

In vivo 23Na NMR studies of myotonic dystrophy

Myotonic dystrophy is an inherited multi-system disease. Its pathophysiology leading to muscle malfunction and damage is not well understood. ²³Na NMR spectroscopy was applied here for an in vivo comparative study of the calf muscles of 7 myotonic dystrophy patients at various stages of the disease and 11 healthy volunteers. Both the total sodium content, expressed as the ratio of the ²³Na and ¹H water signals, and the fast transverse relaxation time, T₂₁, determined from the triple quantum-filtered spectra, increased in correlation with the severity of the disease. The results demonstrate that ²³Na NMR enables the quantitation of myotonic dystrophy progression.     

化工废水中N-亚硝基二正丙胺的吹扫捕集-GC-MS测定法

目的建立简单快速提取并测定N-亚硝基二正丙胺(NDPA)的方法。方法采用Trap3捕集管,利用标准吹扫捕集程序(吹扫气体流速40ml/min,吹扫时间11min,解吸温度225℃,解吸时间4min,烘烤温度230℃,烘烤时间10min),有效富集了化工废水中μg/L级的NDPA,建立了吹扫捕集(P&T)气相色谱质谱联用(GC-MS)化学源(CI)选择离子模式(uSIS)快速、准确分析废水中NDPA的分析方法。结果方法的相对标准偏差为7.5%;废水的加标回收率在62.60%～96.31%;在5～30μg/L范围内线性良好,线性回归系数为0.978;方法的最低检出限为3μg/L。结论采用P&T-GC-MS/CI/uSIS法可用于化工废水中半挥发性有机物NDPA的测定。     

质子磁共振波谱在胶质瘤诊断中的应用

目的探讨质子磁共振波谱（^1Hmagnetic resonance spectroscopy，^1HMRS）在胶质瘤诊断及分级中的应用。方法回顾分析我院2003年3月～2005年9月质子磁共振波谱检查并经病理证实的36例胶质瘤的临床资料，根据胶质瘤恶性程度不同分为A、B2组，其中A组为低恶性组（包括星形细胞瘤Ⅰ级和Ⅱ级、室管膜瘤、少突胶质细胞瘤等）21例，B组为高恶性组（包括星形细胞瘤Ⅲ级和Ⅳ级、多形性胶质母细胞瘤、间变型室管膜瘤、髓母细胞瘤）15例。观察氮乙酰门冬氨酸（Nacetylaspartate，NAA）、胆碱（choline，Cho）、肌酸（creatine，Cr）、肌醇（Ins）的共振峰及比值。大脑对侧对应正常脑组织的结果作内对照组。结果2组胶质瘤均表现为异常的。HMRS，与大脑对侧对应正常脑组织相比，A、B2组表现为NAA／Cr含量显著下降，Cho／Cr含量显著增高（P均〈0．05），cr总量变化不大，且无规律性（P〉0．05），Ins含量表现为轻度下降（P〉0．05）。A组NAA／Cr和NAA／Cho均显著高于B组（t=4．235，P=0．011；t=2．832，P=0．031），A组Cho／Cr显著低于B组（t=-2．323，P=0．042）。结论。HMRs可提高对胶质瘤诊断和分级的准确性。