Rapid and selective determination of free chlorine in aqueous solution using electrophilic addition to styrene by gas chromatography/mass spectrometry.

We developed a rapid and selective method for determination of free chlorine in aqueous solution by gas chromatography/mass spectrometry for the first time. Free chlorine was converted to styrene chlorohydrin using electrophilic addition to styrene in sodium acetate buffer solution (pH 5). The chlorine derivative obtained was extracted with chloroform, and then analyzed by GC/MS. The calibration curve showed good linearity from 0.2-100 µg/mL (as available chlorine). The detection limit was 0.1 µg/mL, and the intra- and interday accuracy were measured at concentrations of 10, 50, and 75 µg/mL to be -1.3 to 6.9% (intraday) and 3.8-8.0% (interday) as % Bias. The precision was between 1.4 and 4.5% as % RSD. These results indicate that this method is a superior technique for the identification of free chlorine. This method was successfully applied to quantification in commercial samples and in samples of a criminal case.

Arthroscopic capsular release for painful throwing shoulder with posterior capsular tightness.

Posterior capsular tightness with glenohumeral internal rotation deficit is usually considered to be an acquired condition of the throwing shoulder and is usually treated conservatively. However, because posterior capsular tightness is sometimes irreversible, we have performed arthroscopic capsular release for painful throwing shoulder with posterior capsular tightness. The true loss of internal rotation and posterior stiffness was confirmed by examination with the patient under anesthesia, and contracture of the posterior capsule and the posterior band of the inferior glenohumeral ligamant was observed arthroscopically. Because an extensive adhesion between the capsule and the fascia of the external rotators was noted, a capsular release was performed from 6 o'clock to 11 o'clock (in the right shoulder) to completely expose the muscle belly of the external rotators. Of the first 16 consecutive patients, 4 had no concomitant lesions and underwent posterior capsular release alone. With a minimum of 2 years' follow-up, it was ascertained that the throwing pain completely disappeared in 14 patients and improved in 2. In all, 11 patients returned to their preinjury performance level, and 5 returned to a lower level of function. In the 4 patients who had no concomitant lesions, throwing pain completely disappeared, and all were able to return to their preinjury performance level.

Arthroscopic Bankart repair with knotless suture anchor for traumatic anterior shoulder instability: results of short-term follow-up.

PURPOSE: To assess the clinical results of arthroscopic Bankart repair with the knotless suture anchor for traumatic recurrent anterior shoulder instability. METHODS: A total of 47 patients with traumatic recurrent anterior shoulder instability and without severe glenoid bone defect who underwent arthroscopic Bankart repair with knotless suture anchors and were followed-up for longer than 2 years were included in the present study. The average age at surgery was 26 years (range, 16 to 49 years), with an average follow-up period of 28 months (range, 24 to 38 months). RESULTS: Clinical score as evaluated by the modified Rowe score advanced from 31 points to 91 points. In all, 35 patients were scored as excellent and 6 as good; the success rate was 87% (41 of 47), and the recurrence rate was 6.4% (3 of 47). External rotation was reduced by 8 degrees at adduction and by 6 degrees at 90 degrees of abduction. Of 12 patients, 7 (58%) returned completely to collision sports at preinjury levels, and 2 of 12 (17%) returned at a lower level. We experienced anchor-related trouble in 3 cases. One was the backwardness of the anchor at 2 months after operation. Breakage of the anchor loop occurred during the procedures in 2 cases. CONCLUSIONS: The clinical results of arthroscopic Bankart repair with knotless suture anchor were favorable; however, some pitfalls, such as the backwardness of the anchor and cutting of the anchor loop, were experienced. When using this anchor, its properties should be well recognized. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Analysis of hallucinogenic constituents in Amanita mushrooms circulated in Japan.

The constituents of seven mushrooms sold as Amanita muscaria or Amanita pantherina (five A. muscaria and two A. pantherina) and four "extracts purported to contain A. muscaria" products that are currently circulated in Japan were determined. All mushroom samples were identified as A. muscaria or A. pantherina by macroscopic and microscopic observation. The dissociative constituents, ibotenic acid (IBO) and muscimol (MUS), were extracted with 70% methanol twice and determined by gas chromatography/mass spectrometry. The IBO (as the hydrate)/MUS contents were in the range of <10-2845ppm/46-1052ppm in the cap of A. muscaria and 188-269ppm/1554-1880ppm in the cap of A. pantherina. In the caps, these compounds had a tendency to be more concentrated in the flesh than in the cuticle. On the other hand, the IBO/MUS contents in the stem were far lower than in the caps. In the "extracts purported to contain A. muscaria" products, IBO/MUS were detected below the lower limit of calibration curve (<10ppm/<25ppm) or not detected. However, these samples contained other psychoactive compounds, such as psychoactive tryptamines (5-methoxy-N,N-diisopropyltryptamine and 5-methoxy-N,N-dimethyltryptamine), reversible monoamine oxidase inhibitors (harmine and harmaline) and tropane alkaloids (atropine and scopolamine), which were not quantified. This is the first report of the chemical analysis of Amanita mushrooms that are circulated in the drug market.

Forced shoulder abduction and elbow flexion test: a new simple clinical test to detect superior labral injury in the throwing shoulder.

PURPOSE: Although several clinical tests for detecting superior labral injury of the shoulder have been reported, some of the maneuvers involved are complicated and diagnosis is still inaccurate. The purpose of this report is to introduce our forced shoulder abduction and elbow flexion test (forced abduction test) along with an assessment of its efficacy in the throwing shoulder in comparison with other clinical tests. TYPE OF STUDY: Prospective nonrandomized clinical trial. METHODS: Fifty-four throwing athletes who underwent arthroscopic surgery were prospectively studied. Superior labral injury was present in 24 cases (Snyder's classification was type 2 in 22, and type 3 in 2). Several clinical tests were performed preoperatively and the results were recorded on our original chart. The condition of the superior labrum was then examined during arthroscopic surgery. The results of these tests were compared with the arthroscopic findings as a standard. The forced abduction test was defined as positive when pain at the posterosuperior aspect of the shoulder on forced maximal abduction was relieved or diminished by elbow flexion. RESULTS: The sensitivity, specificity, and accuracy of the forced abduction test were 67%, 67%, and 67%, respectively. It was one of the most useful tests, along with the crank test and O'Brien's test (crank test, 58%, 72%, 66%; O'Brien's test, 54%, 60%, 57%; respectively). Furthermore, the results of the forced abduction test showed a significant correlation with the presence of superior labral injury (P = .0275, chi-square test). CONCLUSIONS: The forced abduction test was technically simple and its usefulness was comparable to the O'Brien's and crank tests for diagnosing superior labral injury in throwing shoulders. LEVEL OF EVIDENCE: Level II.

Dynamic enhanced MRI of the subacromial bursa: correlation with arthroscopic and histological findings.

OBJECTIVE: To assess dynamic MRI with Gd-DTPA enhancement for evaluating inflammatory changes in the subacromial bursa. DESIGN AND PATIENTS: We detected the signal intensity changes in dynamic MRI of the subacromial bursa, and confirmed these macroscopically by arthroscopy and histologically. The signal intensity was measured using built-in software, and the enhancement ratio (E ratio) was calculated from dynamic MR images. In addition, as a parameter of the rate of the increase in the signal intensity from 0 to 80 s, the mean increase per second in the E ratio was obtained as the coefficient of enhancement (CE). The correlation was studied of the E ratio and CE with the arthroscopic findings (redness, villous formation, thickening and adhesion), and of the E ratio and CE with the histological findings (capillary proliferation, papillary hyperplasia, fibrosis and inflammatory cell infiltration) of the subacromial bursa. Of patients with shoulder pain, this study included those with rotator cuff injury; patients with rheumatoid arthritis or pitching shoulder disorders were excluded. There were 27 patients (15 men, 12 women) ranging in age from 25 to 73 years (mean 49.1 years). Dynamic MRI of the shoulder was also performed on the healthy side of 10 patients and in five normal young volunteers. RESULTS AND CONCLUSIONS: Changes in signal intensity on dynamic MRI were measured in the subacromial bursa. The E ratio (80 s) and CE (0-80 s) were significantly correlated with redness and villous formation as arthroscopic findings, positively correlated with capillary proliferation and papillary hyperplasia as histological findings (p < 0.05), and negatively correlated with fibrosis as a histological finding (p < 0.05) in the subacromial bursa. The patterns of dynamic curves were well correlated with the bursoscopic and histological findings of the synovium of the subacromial bursa. Dynamic MRI appears to correlate with inflammatory activity of synovium of the subacromial bursa. Clarifying the state of the synovium of the subacromial bursa may be useful in determining therapeutic strategies (e.g., indicating topical infusion of hyaluronic acid or steroids for preservative treatment and selecting the site). Furthermore, the evaluation may be useful for indicating surgery, selecting the technique, and evaluating preoperative and postoperative inflammatory changes.

Arthroscopic removal of symptomatic Bennett lesions in the shoulders of baseball players: arthroscopic Bennett-plasty.

BACKGROUND: Bennett lesions are often observed in throwing athletes, and, although usually asymptomatic, they can sometimes become painful and disturb an athlete's throwing ability. Because it is clinically difficult to determine whether a Bennett lesion is symptomatic or whether pain is from another lesion, the outcome of surgical treatment is variable. HYPOTHESIS: Arthroscopic resection of Bennett lesions diagnosed according to our criteria and arthroscopic treatment of associated lesions performed simultaneously were effective for treatment of baseball players with symptomatic Bennett lesions. STUDY DESIGN: Prospective cohort study. METHODS: The following criteria for diagnosis of a symptomatic Bennett lesion were used to identify 16 baseball players who later underwent arthroscopic removal of the symptomatic Bennett lesion (arthroscopic Bennett-plasty): 1) detection of a bony spur at the posterior glenoid rim on radiographs; 2) posterior shoulder pain during throwing, especially in the follow-through phase; 3) tenderness at the posteroinferior aspect of the glenohumeral joint; and 4) relief of pain by injection of local anesthesia. RESULTS: After a minimum follow-up of 1 year, there was no tenderness at the posteroinferior aspect of the glenohumeral joint in any of the patients. Throwing pain disappeared in 10 shoulders and was mitigated in 6 shoulders. Eleven patients returned to baseball at their previous level of competition. CONCLUSIONS: Accurate diagnosis and minimally invasive arthroscopic surgery are important for appropriate treatment of baseball players with symptomatic Bennett lesions.

Augmentation with a Gore-Tex patch for repair of large rotator cuff tears that cannot be sutured.

The objective of this study was to determine the effectiveness of augmentation with a Gore-Tex patch in reconstruction of rotator cuff tears that cannot be repaired by direct suture. Twenty-eight shoulders of 27 patients underwent this procedure. The average age at surgery was 62 years, the average duration of symptoms before surgery was 16 months, and the average follow-up period was 44 months. The shoulders were classified into two groups according to patch size (anteroposterior dimension up to 2 cm or greater than 2 cm). The clinical outcome was evaluated by using the shoulder surgery classification system issued by the Japanese Orthopaedic Association (JOA score), and the postoperative isometric abduction strength at 90 degrees of abduction was assessed by the method of Constant. The average total JOA score improved from 57.7 to 88.7 points, a statistically significant change. There was no difference in the improvement in score between shoulders treated with small patches (12 shoulders) and those treated with large patches (16 shoulders). The average abduction strength was 6.2 kg in the small-patch group and 1.5 kg in the large-patch group, with a statistically significant difference between the two groups. Good clinical results, especially pain relief, could be achieved with this procedure in both the small- and the large-patch groups, but good abduction strength was obtained only in the small-patch group. The mechanism of the improvement by this procedure is still controversial.

Dansyl chloride derivatization of methamphetamine: a method with advantages for screening and analysis of methamphetamine in urine.

The screening and quantitation of methamphetamine (MP) in urine using dansyl chloride (DNC) as the derivatization reagent were studied. Urinary MP derivatized with DNC could be detected by visual observation of the fluorescence in a solid-phase extraction column such as a Sep-Pak C18 cartridge to which the whole reaction solution was applied. The DNC-derivatized MP was eluted from the cartridge and then identified and quantitated by gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). In the GC-MS analysis with the MS detector in the electron-impact mode, DNC-derivatized MP and amphetamine (AP), exhibited diagnostic molecular ion peaks. The intensities of the molecular ions were 15% (DNC-MP) and 35% (DNC-AP) of the base peak (a fragment ion because of the loss of dimethylnaphthalene from M+), demonstrating that this method of derivatization has a major advantage for confirming APs by GC-MS. MP derivatized with DNC could be determined by HPLC with ultraviolet detection. Because a good correlation (r = 0.95) between the GC-MS and HPLC method for urinary MP was confirmed, both HPLC and GC-MS appear to be useful tools for determining urinary MP. The intensity of the cartridge fluorescence due to DNC-derivatized MP was approximately related to the urinary content of MP determined by HPLC or GC-MS, although a false positive in the visual fluorescence was observed in some urinary specimens from healthy volunteers. From these results, screening and confirmation/determination following DNC derivatization is proposed as a suitable method for the analysis of MP.