Detection of triazolam and its hydroxy metabolites in rat hair by reversed-phase liquid chromatography with electrospray ionization mass spectrometry

A sensitive method using reversed-phase liquid chromatography coupled with electrospray ionization mass spectrometry (LC-ESI-MS) for simultaneous determination of triazolam (TZ) and its hydroxy metabolites in hair has been developed. After the addition of deuterium-labeled 1 -hydroxymethyltriazolam (1-HT-d4) as an internal standard, analytes in hair shaft and hair root samples were extracted with a basic medium, CH2Cl2/MeOH/28% NH4OH (20:80:2), at room temperature overnight. The chromatographic separation of the analytes was achieved using a 3-microm micro HPLC column (100 x 2.0-mm i.d.) with a gradient of acetonitrile in water containing 1% acetic acid as the mobile phase at a flow rate of 0.15 mL/min. The mass spectrometer was operated in selected-ion monitoring mode at quasi molecular ions [M+H]+ of TZ and its metabolites. Under the proposed conditions, the ranges of quantitation of TZ, 1-HT, and 4-HT were 0.1-10 ng/0.2 mL. The method has been applied to determine the hair shaft and hair root incorporation of TZ and its metabolites into Dark Agouti rats administered with 3 mg/kg or 6 mg/kg intraperitoneally twice a day for five days. Judging from the retention behavior by the chromatography and the mass spectra of the peaks detected, TZ, 1-HT, and 4-HT were incorporated in the hair shaft and the hair root. The concentration of 4-HT was the highest of all compounds detected. An unknown substance thought to be 1,4-diHT also appeared in both hair shaft and hair root samples. This substance was obtained from in vitro metabolic studies of TZ using rat liver microsome fraction and was accompanied by the other two metabolites, 1-HT and 4-HT. Structural elucidation was performed with online high-performance liquid chromatography-MS after acetylation of the substance with acetic anhydride and pyridine. This is the first report of the detection of the hydroxy metabolites of TZ in hair. The method has been found to be useful as a screening procedure of TZ intake in humans.     

Short dwell times reduce the local defence mechanism of chronic peritoneal dialysis patients

The effect of different intraperitoneal dwell times on the phagocytic capacity of the effluent-derived macrophages in 6 peritoneal dialysis patients was studied. The number of peritoneal cells increased after longer dwell times, and a significant increase in the percentage of macrophages phagocytosing opsonized sheep red blood cells [( IgG]SRBC) and unopsonized latex beads was determined when the dwell time increased from 1.5 to 15 h. Thus, the total phagocytic capacity of the effluent-derived macrophages dramatically increased with prolonged dwell times. In addition, the IgG concentration showed a five-fold increase following long intraperitoneal dwell times. The increasing IgG levels were accompanied by an increase, however not significant (p less than 0.06), in the opsonic activity of the effluents. The increase in local phagocytic and opsonic capacity following longer intraperitoneal dwell times must be taken in consideration by dialysis fluid exchange schedules of peritoneal dialysis patients.     

Superior protective effect of low-calcium, magnesium-free potassium cardioplegic solution on ischemic myocardium. Clinical study in comparison with St. Thomas' Hospital solution

The protective effect of low-calcium, magnesium-free potassium cardioplegic solution on ischemic myocardium has been assessed in adult patients undergoing heart operations. Postreperfusion recovery of cardiac function and electrical activity was evaluated in 34 patients; 16 received low-calcium, magnesium-free potassium cardioplegic solution (group I) and 18 received St. Thomas' Hospital solution, which is enriched with calcium and magnesium (group II). There were no significant differences between the two groups in age, sex, body weight, and New York Heart Association functional class. Aortic occlusion time (107.3 +/- 46.8 minutes versus 113.6 +/- 44.3 minutes), highest myocardial temperature during elective global ischemia (11.5 degrees C +/- 3.1 degrees C versus 9.3 degrees C +/- 3.2 degrees C), and total volume of cardioplegic solution (44.2 +/- 20.5 ml/kg versus 43.4 +/- 17.6 ml/kg) were also similar in the two groups. On reperfusion, electrical defibrillation was required in four cases (25.5%) in group I and in 15 cases (83.3%) in group II (p less than 0.005), and bradyarrhythmias were significantly more prevalent in group II (6.3% versus 44.4%; p less than 0.05). Serum creatine kinase MB activity at 15 minutes of reperfusion (12.3 +/- 17.0 IU/L versus 42.6 +/- 46.1 IU/L; p less than 0.05) and the dose of dopamine or dobutamine required during the early phase of reperfusion (1.8 +/- 2.5 micrograms/kg/min versus 6.1 +/- 3.3 micrograms/kg/min; p less than 0.0002) were both significantly greater in group II. Postischemic left ventricular function, as assessed by percent recovery of the left ventricular end-systolic pressure-volume relationship in patients who underwent aortic valve replacement alone, was significantly better in group I (160.4% +/- 45.5% versus 47.8% +/- 12.9%; p less than 0.05). Serum level of calcium and magnesium ions was significantly lower in group I. Thus low-calcium, magnesium-free potassium cardioplegic solution provided excellent protection of the ischemic heart, whereas St. Thomas' Hospital solution with calcium and magnesium enabled relatively poor functional and electrical recovery of the heart during the early reperfusion period. These results might be related to differing levels of extracellular calcium and magnesium on reperfusion.     

The discussion of the need of mediastinal lymph node dissection in the surgical treatment of lung cancer

The need of lymph node dissection in the case of operative lung cancer with negative mediastinoscopy was discussed. As a preliminary study, the N-number obtained from the mediastinoscopy and that of postoperative examination was compared. The rate of agreement of N-number was as high as 96%. Secondary, 183 cases of lung cancer with squamous-or adenocarcinoma pathologically T-1 or 2. N-0 and P-0 or 1 were picked up and examined. In those cases, the result of 3 years survival rate was 80% in the cases of absolute curative operation and 60% in that of relative non-curative cases, and 5 years survival rate was 70% and 52% respectively, and the cases of absolute curative operation was statistically excellent than that of another group. However, the background of the two groups was different to some degree on account of the advancement of the cancer and the age of the patients. Therefore, the randomized study as for the lymph node dissection in the cases of negative mediastinoscopy was finally performed. In the 30 cases of squamous cell carcinoma where dissection was carried out in 13 cases and not done in 17 cases, the result of 3 years survival was 84% (dissecting group) and 89% (non-dissecting group), and 5 years survival was 73% and 63% respectively. In 23 cases of adenocarcinoma (13; dissecting, 10; non-dissecting), the result of 3 years survival was 100%, 63% and that of 5 years survival rate was 100%, 63% respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of Outcomes of Single-Incision Laparoscopic and Open Appendectomy in Management of Uncomplicated and Complicated Appendicitis

Several reports have demonstrated the effectiveness and feasibility of single-incision laparoscopic appendectomy (SILA). We have introduced SILA including transumbilical laparoscopic-assisted appendectomy (TULAA) and pure single-incision laparoscopic appendectomy (PSILA). A total of 124 patients underwent SILA for acute appendicitis in our department. Our consecutive experiences with SILA are reviewed, and its outcomes including medical treatment cost are compared to open appendectomy (OA). In the SILA group, the mean length of the operation was 65.0 min. Five patients required an additional port insertion, and three patients required open conversion. The postoperative hospital stay was significantly shorter (P < 0.01); an abdominal drain was placed in significantly fewer cases (P < 0.01). There were no significant differences in the total cost medical treatment with OA (P = 0.48). In patients with complicated appendicitis, the hospital stay was significantly shorter in SILA groups. There were no significant differences in all operative outcomes between TULAA and PSILA. SILA represents an expeditious and reliable technique for appendicitis especially in complicated cases. Further assessment including multicenter prospective study is thought to be required to confirm this.     

Reattachment of an osteotomized greater trochanter in total hip arthroplasty using an ultra-high molecular weight polyethylene fiber cable

Background

The optimum approach in total hip arthroplasty (THA) should reduce the risk of postoperative dislocation or limping, be applicable in every case, and be reusable in the future. The purpose of this study was to introduce our transgluteal approach for THA and to evaluate the type and frequency of complications around the greater trochanter.

Modification of the surgical procedure to enable the complete resection of lung cancer with carcinomatous pleuritis

Carcinomatous pleuritis, accompanied by pleural dissemination or malignant pleural effusion, is listed as one of the factors limiting adequate surgical treatment. It is relatively easy to peel the parietal pleura of the chest wall and mediastinum during a pleuropneumonectomy, but it is quite difficult to peel the parietal pleura of the diaphragm. A pleuropneumonectomy was conducted with the combined resection of the pericardium and all layers of the diaphragm without opening of the peritoneum through a posterolateral subcostal approach. This approach thus made it possible to perform a complete resection of the diaphragm relatively easily in a reliable manner, and also contributed to a more thorough resection of pleural dissemination without a second thoracotomy.