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We report the simultaneous screening of highly polar, water-soluble, and less-volatile herbicides, including glyphosate, glufosinate, paraquat, and diquat, in serum using liquid chromatography-mass spectrometry. The herbicides were separated by solid-phase extraction using a Strata-XC cartridge. A heptafluorobutyric acid solution was chosen as the mobile phase for ion-pair liquid chromatography. Mass spectrometry was used for analysis and was optimized for operation in the positive mode for all analytes. The serum specimens were screened for the presence of the herbicides at the following concentrations: 5 ng/mL for glyphosate, 2 ng/mL for glufosinate, 1 ng/mL for diquat, and 5 ng/mL for paraquat. This is the first report on the simultaneous detection of these compounds.

Aristolochic acids (AAs) which exist in plants of the genus Aristolochia are the toxins responsible for aristolochic acid nephropathy (AAN). To investigate the pharmacokinetics and nephrotoxicity of AAs, rabbits were used in this study. The plasma concentrations of the main components of AAs, aristolochic acid I (AA I) and aristolochic acid II (AA II), were determined by a validated high-performance liquid chromatographic method. After intravenous administration of different doses (0.25, 0.5, 1.0, and 2.0mg/kg) of aristolochic acid sodium (AANa) to 4 respective groups of rabbits (n=6 for each dose), linear relationships between the doses of AA I and AA II and the area under the plasma concentration curve (AUC) were found to exist (p<0.001). AANa was also given in escalating doses (0.5, 1.0, and 2.0mg/kg) to the same rabbits at 7-day intervals. The clearance rates of both AA I and AA II significantly decreased with the escalating dose (p<0.001). A nonlinear relationship between the dose and AUC was obtained. Kidney specimens of rabbits were obtained to observe morphological changes on days 1 and 7 after AANa administration. The renal lesions caused by AAs consisted of progressive and dose-dependent tubular damage. However, no remarkable changes in the morphology of glomeruli were observed.

Objective: This study examined test-retest agreement and measurement errors for the Rivermead Mobility Index (RMI) and the Mobility subscale of the Stroke Rehabilitation Assessment of Movement (M-STREAM) in patients with chronic stroke and mild to moderate disability. The authors aimed to determine the level of agreement between test and retest as well as the extent to which a mobility score varies on test-retest measurements., Methods: Both mobility measures were tested on 50 chronic stroke patients twice, 7 days apart. Intraclass correlation coefficient (ICC(2,1)), a relative reliability index, was used to examine the level of agreement between test and retest. Absolute reliability indices, including the standard error of measurement and the smallest real differences, were used to determine the extent to which the mobility scores varied due to chance variation in measurement., Results: Test-retest agreements were excellent for both mobility measures. The standard errors of measurement of the RMI and the M-STREAM, representing the smallest change threshold that indicates a real improvement (beyond measurement error) for a group of individuals, were 0.8 and 1.5, respectively. The smallest real differences of the RMI and the M-STREAM, exhibiting the smallest change threshold that indicates a real improvement for a single individual, were 2.2 and 4.2, respectively., Conclusion: The RMI and the M-STREAM have high agreement between the test-retest measurements with acceptable measurement errors due to variation in measurement. The 2 measures can be used by clinicians and researchers to assess the mobility performance and monitor changes over time in stroke patients.

Murdannia bracteata has been used as a Taiwanese folk medicine for its anti-inflammatory properties. However, neither its active ingredients nor its anti-inflammatory actions are well defined. Nitric oxide (NO), overproduced by activated macrophages via inducible NO synthase (iNOS), is suggested to be a significant pathogenic factor in various inflammatory tissue injuries. In order to elucidate the anti-inflammatory actions of M. bracteata, the present study was designed to isolate its active constituents and examine its effects on iNOS in lipopolysaccharide (LPS)-activated macrophages. Two new hydroxybutenolides, bracteanolide A (1) and B (2), together with (+)-(R)-p-hydroxyphenyllactic acid (3) and isovitexin (4), were isolated and identified from M. bracteata by the NO production assay. All of the compounds inhibited NO production except 3. Their rank order of potency was 1>2>4. Among these, 1 significantly inhibited NO production, which is associated with its suppression on iNOS induction in a concentration-dependent manner, with an IC(50) of 33.27+/-0.86 microM. Nevertheless, isometric tension recordings in isolated endothelium-intact rat aorta revealed that 1-4 did not affect acetylcholine-induced endothelial NO-dependent relaxation, an index of endothelial NOS (eNOS) activity. The selective inhibition on iNOS provides a possible explanation for the anti-inflammatory use of M. bracteata.

Objectives: To evaluate the efficacy of ultrasound-guided percutaneous closed drainage in the management of abscesses in the head and neck., Study Design: Prospective, controlled study., Methods: From January 1998 to December 1999, patients presenting with a unilocular abscess in the head and neck and who subsequently underwent echo-guided percutaneous drainage were enrolled in the study., Results: Fourteen patients were enrolled in the study. No patients needed open surgical drainage afterward. By our protocol, only 8 patients had an indwelling catheter. After treatment, all patients were cured of their disease completely without any complication., Conclusions: Ultrasound-guided percutaneous closed drainage is a safe and effective procedure and might be most beneficial in well-defined and/or unilocular abscess in the head and neck. Closed drainage could be tried initially in an abscess of the deeper visceral spaces and will not impede any subsequent intervention by surgery. Hospital stay can be shortened and potential surgical complications may be avoided by using this procedure.