[Clinical evaluation of in-plane ultrasound-guided thoracic paravertebral block using laterally intercostal approach].

OBJECTIVE: To evaluate the feasibility and success rate of in-plane ultrasound-guided paravertebral block using laterally intercostal approach. METHODS: In the study, 27 patients undergoing elective thoracic surgery were selected to do paravertebral block preoperatively. The fifth intercostal space was scanned by ultrasound probe which was placed along the long axis of the rib and 8 cm lateral to the midline of the spine. The needle was advanced in increments aiming at the space between the internal and innermost intercostal muscles. Once the space between the muscles was achieved, 20 mL of 0.5% (mass fraction) ropivacaine was injected and a catheter was inserted. Whether the tip of catheter was in right place was evaluated by ultrasound image. The block dermatomes of cold sensation were recorded 10, 20 and 30 min after the bolus drug was given. Then 0.2% ropivacaine was infused with 6 mL/h via the catheter by an analgesia pump postoperatively. The block dermatomes of cold sensation and pain score were recorded 1, 6, 24 and 48 h postoperatively. RESULTS: The first attempt success rate of catheteration was 81.48% (22/27); the tips of catheter were proved in right places after the second or third attempt in 5 patients. The median numbers of the block dermatomes 10, 20 and 30 min after the bolus drug was given were 2, 3, 4; the median numbers of block dermatomes were 5, 5, 5, 4, and of pain score were 1, 1, 2, 2 at 1, 6, 24, 48 h postoperatively; no case of bilateral block, pneumothorax or vessel puncture occurred. CONCLUSION: Thoracic paravertebral block using laterally intercostal approach is feasible, which has high success rate of block and low rate of complications.

Comparative study of barnidipine and felodipine in Chinese patients with essential hypertension.

This study evaluated the efficacy and safety of barnidipine for the treatment of mild-to-moderate essential hypertension in Chinese patients. A total of 131 patients were randomized to receive either barnidipine (10 -15 mg) or felodipine (5 - 10 mg) once daily for 4 weeks. Both drugs reduced blood pressure significantly, with > or = 87% of patients obtaining a marked or moderate effect. The mean +/- SD reductions in systolic and diastolic blood pressure were 19.2 +/- 13.6 and 14.4 +/- 7.0 mmHg, respectively, for barnidipine treatment, and 20.3 +/- 11.3 and 14.7 +/- 7.7 mmHg, respectively, for felodipine treatment. There were no significant differences between the two drugs in terms of anti-hypertensive effect, heart rate, laboratory test results or incidence of adverse events. More patients taking felodipine experienced palpitations, but this difference was not statistically significant. Barnidipine is as efficacious and safe as felodipine in the treatment of essential hypertension in Chinese patients.

Biological nitrification and denitrification of opto-electronic industrial wastewater.

Development and application of biological nutrient removal processes accelerated significantly over the past decade due to more stringent nutrients (nitrogen and phosphorus) discharge limits being imposed on wastewater treatment plants. The opto-electronic industry has developed very fast over the past decade in the world. The wastewater often contains a significant quantity of organic nitrogen compounds and has a ratio of over 95% in organic nitrogen (Org-N) to total nitrogen (T-N). In this study, a 2-stage Anoxic/Aerobic pre-denitrification process was established and the efficiency of wastewater treatment was evaluated. Wastewater from an actual LCD-plant was obtained as the sample for looking into the feasibility of opto-electronic industrial wastewater treatment. Hydraulic retention time (HRT) and mixed liquor recycle rate (MLR) were controlled independently to distinguish between the effects of these two factors. Under suitable HRT and mixed liquor recycle ratio, effluents of NH4-N, NOx-N and COD can fall below 20 mg/l, 30 mg/l and 80 mg/l.

Heterogeneous catalytic ozonation of 2-chlorophenol aqueous solution with alumina as a catalyst.

Heterogenous catalytic ozonation of 2-chlorophenol (2-CP) in the presence of gamma-alumina as a solid catalyst has been investigated in this research. It showed that the rate for degradation of TOC could increase from 21% to 43%. The pseudo-first reaction constants of 2-CP could increase from 0.8688 min-1 to 0.1270, increasing by approximately 40%. At the same time, the consumption of ozone was only half that of ozone alone. This research also explored the effects of the catalyst dosage, pH values and removal kinetics of 2-CP. In addition, three consecutive running with the same catalyst revealed insignificant reduction of the activity. Furthermore, the elimination of toxicity was evaluated by Microtox analysis. The detoxification was more stable and with good results.

Effects of dofetilide, a class III antiarrhythmic drug, on various ventricular arrhythmias in dogs.

Dofetilide, a new class III antiarrhythmic agent, was tested in various kinds of canine ventricular arrhythmias to compare its effects with those of other class III agents. Ventricular arrhythmia models used were induced by two-stage coronary ligation, digitalis, epinephrine, coronary ligation and reperfusion, and programmed electrical stimulation (PES). Dofetilide (100 micrograms/kg intravenously) did not suppress automaticity arrhythmias induced by two-stage coronary ligation and epinephrine or the coronary ligation and reperfusion arrhythmias, but suppressed the reentry arrhythmia induced by PES in dogs with old myocardial infarction (MI). This effect was associated with a prolongation of QT interval. Dofetilide also showed antiarrhythmic effect in some dogs with digitalis arrhythmia. Dofetilide increased QT interval and showed negative chronotropic effect like that of other class III drugs, but was different in antiarrhythmic profiles from those of other class III agents such as D-sotalol, E-4031, and MS-551 in that it did not prevent the occurrence of ventricular fibrillation (VF) immediately after coronary reperfusion and had some antiarrhythmic effects on digitalis arrhythmia.

Studies on contractures induced in mouse diaphragm by caffeine and cupric and selenite ions.

Mouse diaphragm contractures induced by Cu2+, caffeine and selenite were studied comparatively. Both Cu2+- and caffeine-contractures were produced rapidly and relaxed spontaneously; the selenite-contracture occurred after a latent period of about 45 min and lasted for more than 3 hr. All contractures were myogenic, since neither d-tubocurarine nor tetrodotoxin prevented them. The susceptibility of these contractures to the depletion and replenishment of Ca2+ differed: the Cu2+-contracture increased proportionally with rising extracellular Ca2+ concentrations ranging from 2.5 to 12.5 mM and were abolished by 5 mM EGTA. Caffeine- and selenite-contractures were not affected by changes in extracellular Ca2+ concentration. The caffeine-contracture was abolished by EGTA in high concentration (30 mM) and the selenite-contracture was inhibited by 50 mM EGTA. After removal of Ca2+ with 5 mM EGTA, followed by replacement with 2.5 mM Ca2+ for 1 min, the Cu2(+)-contracture was fully restored. Caffeine- and selenite-contractures were restored only after a longer period (10-20 min) of re-exposure to Ca2+. These findings suggest that the Cu2(+)-contracture is dependent on external Ca2+ and probably caused by an increasing Ca2+ entry through sarcolemma. Caffeine- and selenite-contractures apparently result from internal Ca2+ release by sarcoplasmic reticulum. Substitution of either Sr2+ or Co2+ for Ca2+ fully supports the Cu2(+)-contracture. 45Ca2+ uptake and calcium content of the diaphragm were markedly increased by Cu2+ but not by selenite. Furthermore, the Cu2(+)-contracture was inhibited by exposing the outer membrane to trypsin, phospholipase C or saponin. The selenite-contracture was inhibited only by trypsin. The caffeine-contracture was unaffected by these treatments. These results support the notion that the Cu2(+)-contracture is induced by an increased entry of Ca2+ through the outer membrane. Cu2(+)-, caffeine- and selenite-contractures were respectively abolished, potentiated and unaffected by chronic denervation of the diaphragm. This and the other findings provide evidence that Cu2(+)-, caffeine- and selenite-contractures are induced in mouse diaphragm muscle via different sites of action.

New humantenine-type alkaloids from Gelsemium elegans.

The alkaloid extract of the whole plant of Gelsemium elegans has afforded four new alkaloids: N-desmethoxyrankinidine [1], 11-hydroxrankinidine [3], 11-hydroxyhuman-humantenine [4] and humantenirine [6]. The structures of 5 was established through X-ray crystallographic analysis, and the structures of the other three new alkaloids were deduced by spectral analysis (1H, 13C, APT, 2D-COSY and 2D-HETCOR).

Hematoporphyrin phototherapy for experimental intraocular malignant melanoma.

Administration of a hematoporphyrin derivative (HpD) followed by photoradiation with red light completely or partially destroyed Greene hamster melanoma developed in the anterior chamber of rabbit eyes. Tumor-bearing eyes were divided into two groups. Twenty-two eyes received an HpD injection followed by exposure to red light from a slide projector with a 500-W quartz halogen lamp and a red filter (intensity to the tumor was about 4.0 mW/sq cm). In the control group (six eyes), eyes were exposed either to red light only or to HpD injection only. Local complications after therapy included edema and congestion of the conjunctiva, clouding of the cornea, and hemorrhage on the iris surface. The HpD itself has no cytotoxic effect, is preferentially retained in tumor cells, and causes a destructive photodynamic effect as a result of the production of cytotoxic singlet oxygen in the tumor. Accordingly, it may be a safe and potentially therapeutic procedure in the treatment of uveal melanoma.