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Biomedical subjects

W S Guo

Publications and source records attributed to W S Guo.

8 recordsLinked to original sources
PubMed2001

[Selective isolation of anethole from volatile oil of Foeniculum vulgare Mill by inclusion crystalline with chela-shape host].

AIM: To isolate the components from the volatile oil of Foeniculum vulgare Mill. METHODS: According to the function of molecular recognition of supramolecular chemistry, chela shape molecule, trans-1, 2-biphenyl-1, 2-acenaphthendiol was used as host molecule and the volatile oil of Foeniculum vulgare Mill as guest molecule. Trans-1, 2-biphenyl-1, 2-acenaphthendiol can recognize the components that endowed with interactional complementarity and form inclusion compound as crystals. RESULTS: The anethole in the volatile oil was selectively included as trans-1,2-biphenyl-1,2-acenaphthendiol which was obtained in pure state from the inclusion compound by Kugelrohr vacuum technology. The formation of inclusion compound was confirmed by means of IR and powder XRD. The structure of the selectively isolated component was elucidated as trans-anethole by means of IR, 1HMMR and MS. CONCLUSION: The experimental results showed that the method is simple, rapid and selective for isolation anethole from volatile oil of Foeniculum vulgare Mill.

Allylbenzene Derivatives↗
PubMed2000

[Selective isolation of isopsoralen from crude extract of Psoralea corylifolia. L by using inclusion method of host-guest molecules].

AIM: To isolate the chemical components from extracted crude of Psoralea corylifolia L. METHODS: Applicate the function of molecular recognition in supramolecular chemistry, use 1,1,6,6-tetraphenylhexa-2,4-diyne-1,6-diol as the host molecule and chemical components in extracted crude of Psoralea corylifolia L. as guest molecules, which represent different from either in sort, quantity and sites of function groups or in structural topological character, 1,1,6,6-tetraphenylhexa-2,4-diyne-1,6-diol could selectively form inclusion compound with component endowed with interactional complementarity and isolate as crystalline from the extracted crude of Psoralea corylifolia L. RESULTS: The isopsoralen as guest molecule is selectively included by 1,1,6,6-tetraphenylhexa-2,4-diyne-1,6-diol in inclusion crystal and removed by acetone from the inclusion compound and total yield is 0.18%. Isopsoralen is determined by UV, IR, 1HNMR and MS and its inclusion compound is determined by means of IR, powder XRD and single crystal XRD. The isolation effect is analyzed by GC/MS. CONCLUSION: The method is simple and selective for isolation isopsoralen from extracted crude of Psoralea corylifolia L.

Furocoumarins↗
PubMed1997

Endoscopic variceal ligation in prophylaxis of first variceal bleeding in cirrhotic patients with high-risk esophageal varices.

To determine the efficacy of endoscopic variceal ligation (EVL) in prophylaxis on the rate of first esophageal variceal bleeding, we conducted a prospective, randomized trial in 126 cirrhotic patients with no history of previous upper gastrointestinal bleeding and with esophageal varices endoscopically judged to be at high risk of hemorrhage. The end-points of the study were bleeding and death. Life-table curves showed that prophylactic EVL significantly diminished the rate of variceal hemorrhage (12/62 [19%] vs. 38/64 [60%]; P = .0001) and overall mortality (17/62 [28%] vs. 37/64 [58%]; P = .0011). The 2-year cumulative bleeding rate was 19% (12/ 62) in the EVL group and 60% (38/64) in the control group. The 2-year cumulative mortality rate was 28% (17/62) in the EVL group and 58% (37/64) in the control group. Comparison of Kaplan-Meier estimates of the time to death of both groups showed significantly lower mortality in the ligation group (P = .001). Patients undergoing EVL had few treatment failures and died mainly of hepatic failure. The lower risk in the EVL group was attributed to a rapid reduction of variceal size. Prophylactic EVL was more efficient in preventing first bleeding in patients with good condition (Child A) than in those with decompensated disease (Child B and C). We conclude that prophylactic EVL can decrease the incidence of first variceal bleeding and death over a period of 2 years in cirrhotic patients with high-risk esophageal varices.

Aged↗
PubMed1996

Characteristics of patients with benign gastric outlet obstruction requiring surgery after endoscopic balloon dilation.

OBJECTIVES: The aim of this study is to identify factors that will predict which patients with benign gastric outlet obstruction will not respond to endoscopic balloon dilation, in a long-term observation. METHODS: Over a 51-month period, 42 patients with benign gastric outlet obstruction received endoscopic balloon dilation. The "through-the-scope" technique with the aid of a guide wire was used for dilation. Fifteen factors were analyzed prospectively in 40 patients. Multivariate analysis was used to find the independent factors of the failure of treatment. RESULTS: The median follow-up period was 23 months (range 1-51 months). Twenty-eight (67%) patients achieved sustained improvement, and 14 (33%) patients underwent surgery. The overall symptom-free rates in 12, 24, 36, and 48 months were 85.3%, 78%, 68.8%, and 68.8%, respectively. The independent prognostic factor for failure of treatment was the need for more than two courses of endoscopic balloon dilation to relieve symptoms (odds ratio, 6.857; 95% confidence interval, 1,031-45,606). CONCLUSIONS: Endoscopic balloon dilation for the treatment of benign gastric outlet obstructions is an effective alternative to surgery. Patient who needs more than two courses of endoscopic balloon dilation to relieve symptoms should receive surgery.

Adult↗
PubMed1995

A randomized study comparing glucagon and hyoscine N-butyl bromide before endoscopic retrograde cholangiopancreatography.

BACKGROUND: This study tried to resolve whether glucagon is a better premedication for endoscopic retrograde cholangiopancreatography (ERCP). METHODS: We first measured the basal blood sugar and amylase levels. Then an endoscope was placed in the duodenum without premedication, and basal pulse and duodenal peristaltic rates were measured. ERCP began after studied subjects were randomly premedicated with either 1 mg glucagon (n = 38) or 40 mg hyoscine N-butyl bromide (n = 36) intravenously. Ten minutes later the variables were measured again. RESULTS: Glucagon elicited hyperglycemia whereas hyoscine N-butyl bromide manifested an anticholinergic effect. No difference was found between these two groups with regard to the necessary interval for ERCP (20.6 +/- 14.1 min versus 21.4 +/- 14.7 min; NS) or the success rate for cholangiopancreatography (92.1% versus 91.7%; NS). Neither hyperamylasemia nor pancreatitis was preventable when glucagon was used. CONCLUSIONS: The two premedications appear equally effective in the performance of ERCP.

Aged↗
PubMed1994

Endoscopic injection for the treatment of bleeding ulcers: local tamponade or drug effect?

Fifty-two patients with Forrest Ia or Ib bleeding ulcers were randomized to receive endoscopic injection therapy with either 1:10,000 epinephrine in water (Group I) or distilled water (Group II). Twenty-five out of 27 patients in group I, versus 22 out of 25 patients in group II, achieved initial hemostasis after endoscopic injection therapy (p > 0.05). Five patients who did not respond to local injection had bleeding controlled by heater probe thermocoagulation or surgical intervention. Three patients in each group developed rebleeding after initial hemostasis. Four of these patients had bleeding controlled by surgical intervention, while the other two died of underlying diseases. No change in systemic blood pressure, but a significant drop in the pulse rate were noted in both groups after injection therapy. Patients with shock at admission or ulcer size greater than 2 cm had a significantly higher rebleeding rate after initial hemostasis than patients with normal blood pressure and ulcers under 2 cm (p < 0.05). No serious complications were observed after injection therapy, and no significant difference in the amounts of solution required for successful hemostasis was noted between the two groups. We conclude that a local tamponade with distilled water is as effective and safe as diluted epinephrine solution for endoscopic injection therapy.

Double-Blind Method↗
PubMed1994

The changes of serum acidic markers in human subjects receiving pharmacological dosage of antispasmodics.

BACKGROUND: Anticholinergic and glucagon result in the diminished gastric acid secretion, it is unknown whether these agents may again influence serum acidic markers. METHODS: The changes of serum levels of acidic markers represented with gastrin and pepsinogen I at 10 min after the injection of either hyoscine-N-butyl-bromide (HNBB) 20 mg (n = 31) or glucagon 1 mg (n = 32) were investigated when these subjects were receiving endoscopic retrograde cholangiopancreatography for various reasons. RESULTS: At this period, both medications exerted an antispasmodic action on the duodenum. An anticholinergic effect was seen only among the HNBB group, whereas hyperglycemia appeared among the glucagon group. HNBB did significantly inhibit serum pepsinogen I levels when compared with their basal levels (mean +/- SD: 92.1 +/- 33.2 ng/ml vs. 83.2 +/- 27.4 ng/ml, P < 0.01). However, HNBB did not influence serum gastrin levels. Glucagon inhibited both serum pepsinogen I (89.1 +/- 39.7 ng/ml vs. 80.5 +/- 37.4 ng/ml, P < 0.005) and gastrin (79.3 +/- 31.3 pg/ml vs. 71.3 +/- 23.8 pg/ml, P < 0.01) levels compared with their basal levels. CONCLUSIONS: Present observations indicate that glucagon and HNBB may inhibit serum PGI level, whereas the former has the additional effect of inhibiting serum gastrin level.

Butylscopolammonium Bromide↗