Common bile duct calculi: updated experience with dissolution with methyl tertiary butyl ether

The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control.     

Clinical MR imaging with a Helmholtz-type surface coil

Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution.     

Enhancement of chemotactic factor-stimulated neutrophil oxidative metabolism by leukotriene B4

Leukotriene B4 (LTB4) is a potent primary stimulator of neutrophil chemotaxis, aggregation, and degranulation and induces superoxide production at higher concentrations. In order to determine whether LTB4 modulates neutrophil responses to oxidative stimuli, human neutrophils (PMNs) were incubated with LTB4 prior to stimulation with f-Met-Leu-Phe (fMLP, 10(-7) mol/L), opsonized zymosan (OZ, 250 micrograms/mL), or phorbol myristate acetate (PMA, 32 nmol/L). Superoxide (O2-) production by stimulated PMNs was assessed by the superoxide dismutase-inhibitable reduction of cytochrome c. LTB4 alone did not stimulate O2- production in concentrations below 10(-7) mol/L and had no effect on the O2- assay. In the concentration range of 10(-12) to 10(-8) mol/L, LTB4 did not alter O2- release induced by OZ or PMA. In contrast, LTB4-treated cells demonstrated enhanced O2- production following exposure to fMLP, and in the presence of 10 nmol/LLTB4, generated 180% +/- 41% of O-2 quantities produced by control cells (n = 23). Enhancement was LTB4 dose-dependent, was maximal in the range of 1 to 10 nmol/L LTB4, was not reversed by removal of the lipid from the medium prior to fMLP stimulation, and was not dependent on the presence of Ca++ or Mg++ in the suspending medium. Chemiluminescence of fMLP-stimulated neutrophils was increased to 323% of controls in neutrophils preincubated with 10 nmol/L LTB4. Unlike augmentation of oxidative responses to fMLP seen with other degranulating stimuli, enhancement by LTB4 was not correlated with an increase in 3H-fMLP receptor binding. These results indicate that, in addition to its primary effects on neutrophil function, LTB4 modulates PMN oxidative responses to the chemotactic peptide and, thus, may amplify the release of oxygen metabolites at inflammatory foci.     

Proton spectroscopic imaging (Dixon method) of the liver: clinical utility

The contribution of proton spectroscopic (PS) imaging to magnetic resonance (MR) imaging of the liver was assessed at 0.5 T in 55 patients with known or suspected hepatic malignancy. PS images were compared subjectively with T1- and T2-weighted spin-echo (SE) images for hepatic lesion detection and conspicuity. For hepatic metastases (n = 27), PS images were equal to T1-weighted images in lesion detection in 17 patients but showed fewer lesions in five patients and false-negative results in two. When compared with T2-weighted images, PS images depicted more lesions in six patients, an equal number of lesions in 18, and fewer lesions in two. Hepatomas (n = 8) were detected with each sequence in all patients. Hepatomas were often more conspicuous on PS images than on T2-weighted images; they were of equal conspicuity on PS and T1-weighted images in most cases. Whereas fatty infiltration (n = 16) appeared on PS images as areas of low signal intensity similar to that of paraspinal muscle, it produced no detectable abnormality on either T1- or T2-weighted images. PS imaging is inferior to T1-weighted SE imaging in the detection of hepatic metastases. The major role of PS imaging at intermediate field strength is to differentiate focal fatty infiltration from hepatic metastases.     

Eversion and inversion muscle group peak torque in hyperpronated and normal individuals

BackgroundExcessive subtalar pronation causes significant changes in the biomechanics of the lower leg, adversely influences proprioceptive feedback and neuromuscular reflex behavior and consequently, affects stability of the foot. However, the changes in muscle strength, caused by hyperpronation are unclear.ObjectivesThe purpose of the present study was to compare the evertor and invertor peak torque between hyperpronated and normal individuals as well as between their dominant and non-dominant foot.Method20 healthy male participants volunteered for this study. Leg dominance was assessed on the basis of a questionnaire and navicular drop measurements were used to classify participants into two groups: hyperpronated (≥10 mm) and normals (5–9 mm). Isokinetic concentric eversion and inversion muscle group strength was tested at 30° and 120°/s using the Con-Trex MJ isokinetic dynamometer.ResultsIn all cases, inversion peak torque was greater than eversion peak torque and declined with increasing angular velocity. No significant differences were found for inversion and eversion concentric strength at both speeds tested, neither between normal and hyperpronated individuals neither between their dominant and non-dominant foot.ConclusionsThese results indicate the need re-evaluation of navicular drop values in order to identify normal and abnormal subtalar pronation. The assessment of eccentric contractions is also proposed when examining invertors and evertors isokinetic strength.     

高效液相色谱法测定炎痛净乳膏中双氯芬酸钠和苯佐卡因的含量

目的：测定炎痛净乳膏中双氯芬酸钠和苯佐卡因的含量。方法：高效液想象以谱法，甲醇为提取溶剂，地西泮为内标，No-va-PakC18色谱柱，甲醇-水-冰醋酸（80：20：0.5)为流动相，检测波长为283nm。结果：双氯芬酸钠和苯佐卡因在5μg/ml-40μg/ml范围内，其浓度与峰面积均呈良好的线性关系（r=0.9999)，平均回收率分别为101.0%,RSD=1.21%,99.8%,RSD=0.62%。结论：本法专属性强，操作简便，结果准确。