Biomedical subjects

S Yang

Publications and source records attributed to S Yang.

At least 379 records · Page 21Linked to original sources

PubMed1997

Relationship between hepatic blood flow, liver tests, haemodynamic values and clinical characteristics in patients with chronic liver disease.

Although hepatic blood flow (HBF) has been measured in patients with liver disease for many years, the results of these studies have not provided clear information concerning the usefulness of this measurement. Hepatic blood flow was measured in 392 patients with either cirrhosis (n = 356) or hepatic fibrosis (n = 36). The control group included 59 subjects with normal liver architecture. Hepatic clearance of indocyanine green (ICG) was markedly reduced in patients with cirrhosis and hepatic fibrosis compared with controls (182 +/- 5, 276 +/- 22 and 421 +/- 25 mL/min, respectively). In patients with cirrhosis, ICG clearance and extraction were significantly correlated, but were not correlated to HBF. Although HBF did not differ between patients with cirrhosis and controls (1.26 +/- 0.04 vs 1.35 +/- 0.07 L/min, respectively), patients with hepatic fibrosis had lower HBF (1.04 +/- 0.07 L/min; P < 0.05). In patients with cirrhosis, no correlation was observed between HBF and cardiac output, mean arterial pressure, azygos blood flow, the hepatic venous pressure gradient or Pugh's score. However, a significant difference in HBF was observed in patients with and without hepatic encephalopathy (1.00 +/- 0.09 vs 1.28 +/- 0.03 L/min, respectively; P < 0.05). In conclusion, the present study shows that, in patients with cirrhosis, HBF is normal and is not related to other haemodynamic values or liver tests. These results discourage the measurement of HBF in the evaluation of patients with cirrhosis.

Aged↗

PubMed1997

The effect of panic attack on mitral valve prolapse.

It has been reported that panic attacks might cause mitral valve prolapse (MVP) via haemodynamic or indirect effects. Such prolapse can be classified as being physiological (benign course) or pathological (poor course). It is therefore important to consider whether panic attacks, as a risk factor for MVP, are associated with its physiological or pathological type. Our study sample consisted of two groups of patients with panic disorder (PD), one having onset within 1 year (n=24) and the other with a history of more than 10 years (n=21). Demographic data, symptom presentations, auscultatory and echocardiographic findings of both groups were compared, but no significant difference was found except with regard to anticipatory anxiety. It is concluded that panic attack exerts no significant effect on mitral valve prolapse.

Adult↗

PubMed1997

Synergistic anticryptosporidial potential of the combination alpha-1-antitrypsin and paromomycin.

The combined effect of the serine protease inhibitor alpha-1-antitrypsin (AAT) and the aminoglycoside paromomycin on Cryptosporidium parvum infection in vitro was investigated. AAT and paromomycin were mixed with C. parvum oocysts as either single or combined treatments and used to inoculate epithelial cell cultures. Single- and combined-treatment groups had significantly lower (P < 0.01) parasite numbers than untreated controls. The mean fractional inhibitory concentration indices suggested significant synergistic activity.

Animals↗

PubMed1997

Inhibition of recombinant human immunodeficiency virus type 1 replication by a site-specific recombinase.

Current molecular genetic strategies to inhibit productive human immunodeficiency virus type 1 (HIV-1) replication have involved the generation of gene products which provide intracellular inhibition of essential virally encoded proteins or RNA structures. A molecular strategy to excise proviral DNA from HIV-1-infected cells and render these cells virus free would provide an attractive direct antiviral strategy, providing a mechanism to remove viral genes from infected cells. The potential of such a molecular genetic intervention was examined by using the Cre-loxP recombination system. A recombinant HIV-1 clone, designated HIV(lox), that contains loxP within a nonessential U3 region of the long terminal repeats was synthesized. The loxP motif was maintained during replication of HIV(lox) in CEM cells, as demonstrated by reverse transcriptase PCR analyses of genomic RNA isolated from virions. Two different types of HIV-1-permissive cells, CEM cells and 293 cells expressing the CD4 glycoprotein, were transformed with a Cre expression vector which was shown to encode Cre DNA binding and recombinase activities. HIV(lox) infection of CEM or CD4+ 293 cells expressing Cre resulted in a substantial reduction in virus replication compared to control cells, and evidence for the presence of the expected excision product was found. Site-specific excision of HIV-1 can therefore be achieved by using this model system with acute infection. These studies represent one step toward the development of a novel antiviral strategy for the treatment of AIDS.

Anti-HIV Agents↗

PubMed1997

Relationship between portal pressure, esophageal varices, and variceal bleeding on the basis of the stage and cause of cirrhosis.

BACKGROUND AND METHODS: Hepatic venous pressure gradient, esophageal varices, and variceal bleeding were investigated in 957 patients with cirrhosis. The causes (alcoholic/virus) and stage (Child-Pugh's classification) of cirrhosis were also taken into account. RESULTS: The prevalence of variceal bleeding was 35% in patients with large varices and 17% in those with small varices (P < 0.05). It was higher in patients with alcoholic cirrhosis (41% and 19%, respectively) than in those with viral cirrhosis (22% and 10%, respectively). In patients with alcoholic cirrhosis the hepatic venous pressure gradient was higher in Child A and B patients with small or large varices than in those with no varices; these differences were not found in Child C patients and in patients with viral cirrhosis. In all subgroups the pressure gradient was higher in Child C patients than in Child A patients. There was no significant difference in the hepatic venous pressure gradient between patients with varices and previous variceal bleeding and those with no bleeding whatever the stage of cirrhosis. CONCLUSIONS: This study shows that the hepatic venous pressure gradient is associated with the stage and causes of cirrhosis and the presence of varices. These factors should be taken into account in studies evaluating the hepatic venous pressure gradient in heterogeneous groups of patients.

Esophageal and Gastric Varices↗

PubMed1997

Effect of melittin on ion transport across cell membranes.

Extensive work with melittin has shown that the venom has multiple effects, probably, as a result of its interaction with negatively changed phospholipids. It inhibits well known transport pumps such as the Na(+)-K(+)-ATPase and the H(+)-K(+)-ATPase. Melittin increases the permeability of cell membranes to ions, particularly Na+ and indirectly Ca2+, because of the Na(+)-Ca(2+)-exchange. This effect results in marked morphological and functional changes, particularly in excitable tissues such as cardiac myocytes. In some other tissues, e.g., cornea, not only Na+ but Cl- permeability is also increased by melittin. Similar effects to melittin on H(+)-K(+)-ATPase have been found with the synthetic amphipathic polypeptide Trp-3.

Animals↗

PubMed1997

[Treatment of congenital glaucoma with trabeculotomy].

OBJECTIVE: To investigate the method of localization of Schlemm's canal during trabeculotomy to evaluate the successful rate of trabeculotomy. METHOD: The author treated 38 cases (46 eyes) of congenital glaucoma with trabeculotomy. Harms trabeculotomy knife was introduced into the Schlemm's canal through the cutting end of an external collecting channel. The follow-up period was over 6 months in 37 eyes. RESULTS: The intraocular pressure, C/D ratio were significantly improved after surgery compared to the preoperative ones (P < 0.05). But no significant differences were found in the corneal diameter, the depth of the anterior chamber, the length of ocular axis before and after surgery (P > 0.05). The intraocular pressure of 27 eyes (73.0%) was less than or equal to 2.8 kPa (1 kPa = 7.5 mmHg), showing good control of glaucoma. CONCLUSION: During trabeculotomy, the trabeculotomy knife introduced in to the Schlemm's canal through an external collecting channel is a better and accurate method of localization of Schlemm's canal. The method is relatively simple, reliable and has certain value in clinical application.

Child↗

PubMed1997

[Serotype distribution of Actinobacillus actinomycetemcomitans].

A total of 131 Actinobacillus actinomycetemcomitans clinical strains from 28 periodontally healthy or diseased subjects were serologically categorized by indirect enzyme-linked immnosorbent assay. Sepecies-specific and serotype b, c-specific monoclonal antibodies against Actinobacillus actinomycetemcomitans were used. Preliminary data revealed that each subject harbored only one serotype of Actinobacillus actinomycetemcomitans. The distribution of serotype a, b and c were respectively 11%, 21% and 68%, both of periodontally healthy subjects harbered serotype b, 7 of 9 juvenile periodontitis subjects harbered serotype c, 12 of the other subjects which included 3 adult periodontitis and 14 gingivitis harbered serotype c.

Adolescent↗

PubMed1997

[Clinical observations on syringomyelia treated by syrinx-peritoneal shunting with "T" tube].

We 22 cases of syringomyelia were verified by MR and treated by syrinx-peritoneal shunting with "T" tube. After the operation, the patients were reexamined by MR and B ultrasound and confirmed that their shunting was functional. Symptoms of the patients disappeared. But four patients got slight numbness in one leg or at the saddle area. One patient suffered from a difficult movement in one hand. With the exception of 6 patients, 16 showed that both of the newly and original symptoms improved significantly. Follow up for 2 years with regular MR and B ultrasound reexaminations was made. The patients resumed their work and study. MR and B ultrasound reexaminations showed that all of syrinxes collapsed significantly as the same as that after the operation immediately. These mean that this kind of operation is useful and effective for most syringomeylias.

Adolescent↗

PubMed1997

[Effects of estrone on transmission at neuromuscular junction of the toad].

The effects of estrone on neuromuscular transmission were studied intracellularly at the muscle fiber endplate in isolated sciatic nerve-sartorius muscle preparations of the toad (Bufo bufo gargarizans) in vitro. The results showed that estrone (10(-4) mol/L), added to bath medium, caused an increase in amplitudes of endplate potentials (EPP) both in 10 micrograms tubocurarine treated and 10 mmol/L MgCl2 treated preparations, but the increase was more prominent in the former, and that estrone, 30 min after being added to bath medium, caused clear increase both in frequency and amplitude of miniature endplate potentials (MEPP), but the wave form of MEPP remained unchanged and the resting membrane potentials were also unchanged. These results suggest that estrone can increase neuromuscular transmission, which seems to involve primarily the presynaptic mechanism.

Animals↗

PubMed1997

[Application of serum bile acid chromatography to the diagnoses of liver diseases].

In order to explore the specificity of serum bile acid (SBA) chromatograph in the diagnoses of different kinds of hepatosis, we investigated by means of gas chromatography the changes of serum bile acids in workers who exposed to hexogen or chloroethylene and in patients who suffered from hepatosis such as acute jaundice hepatitis, chronic active hepatitis, cirrhosis and liver cancer. The results revealed different disturbances of SBA occurring in the liver injuries induced by the two kinds of hepatotoxicant. Serum lithocholic acid (LCA), deoxycholic acid (DCA) and chenodeoxycholic acid (CDCA) in workers exposed to hexogen and wre significantly different from those of the control group respectively (P < 0.01, P < 0.01, P < 0.05); on the other hand, only serum LCA and DCA went up in workers exposed to chloroethylene (P < 0.0005, P < 0.001). The main changes both concentrated on the secondary bile acids. In acute jaundice hepatitis, chronic active hepatitis, cirrhosis and liver cancer, serum LCA, DCA, CDCA and cholic acids (CA) all went up in different degrees compared with the control group respectively (P < 0.005, P < 0.025, P < 0.005, P < 0.005). But no difference was noted among the 4 kinds of bile acids (P > 0.5), except that between CA and CDCA. These provided the evidence of the diagnosis and identification of clinical hepato-biliary diseases and occupational liver injures.

Cholic Acids↗

PubMed1997

[Diagnosis and management of Mondini malformation].

Owing to the development of imaging technology and audiology, some of the sensorineural hearing loss cases that were previcusly considered to be of unknown cause have been found to be inner ear malformation. Five cases of Mondini malformation are reviewed in this paper. CSF otorhinorrhea occurred in four cases, Klippel-Feil syndrome in three, and concurrent otosclerosis in one patient. In discussion, the authors point out that: 1) CT scanning is an supplement to audiologic tests for such patients; 2) perilymph fistula in Mondini malformation is often found at the oval window and its vicinity, the foot plate and the round window; 3) the fistula can be treated by plugging with fascial tissue via tympanoplastic approach with endaural incision. The mucosa around the fistula should be stripped away and the plugging tissue should be of dumb-bell shape.

Adolescent↗

PubMed1997

[Optimal high-yield agronomic measures for Curcuma longa L].

Regression method of orthogonal conic substitution with factors was employed to build up a tuber yield simulation model. Three main measures (sowing time, plant population, application rate of fertilizer) affecting the tuber yield were analyzed by the mathematical model of three unknown second order orthogonal rotative regression. The optimal agronomic measures were obtained. The results indicate that sowing time and plant population play a important role in raising the tuber yield. Sowing time is clearly interrelated with plant population, and likewise, plant population application rate of fertilizer.

Fertilizers↗

PubMed1997

[Chemical constitutents of Podocarpus imbricatus BI. (II)].

From Podocarpus imbricatus five compounds were isolated and identified as 2"-O-rhamnosylvitexin (I), hinokiflavone (II), ecdysterone (III), beta-sitosteryl heptadecoate (IV) and daucosterol(V) on the basis of spectral studies (UV, IR, 1HNMR, 13CNMR, MS) and chemical reactions. I, II, III, IV are obtained from this plant for the first time, and IV is obtained as beta-sitosteryl odd number carboxylic ester for the first time.

Biflavonoids↗

PubMed1997

[Anticarcinogenic effect and hormonal effect of Cordyceps militaris Link].

Cordyceps militaris (CML) has been found good for inhibiting the growth of tumor, prolonging the survival period of mice implanted with S180, inhibiting the growth and metastasis of Lewis pneumonic cancer in the implanted mice, increasing the plasm content of cortisol and testosterone in normal rats, and elevating the weight of sexual organs in normal and castrated rats. CML exerts a malehormone-like effect.

Animals↗

PubMed1997

[Chemical composition of Fagopyrum cymosum (Trev.) Meisn].

From the ethanolic extracts of the aerial parts of Fagopyrum cymosum, eleven compounds were isolated, of which eight have been identified as benzoic acid(1), beta-sitosterol(2),5,5'-di-alpha-furaldehyde dimethyl ether(3), p-hydroxybenzoic acid(4), rutin(5), quercetin(6), daucosterol(7), succinic acid(8) by spectroscopic methods. Compound 3 is obtained from the genus for the first time.

Drugs, Chinese Herbal↗

PubMed1997

[Detection of hepatitis G virus RNA in sera in non A-E hepatitis patients using polymerase chain reaction with multiple set primers].

A double polymerase chain reaction, involoving nested primers deduced from NS3-5 regions of the hepatitis G virus (GBV-c/HGV) genome, was developed for a sensitive and specific detection of GBV-C (HGV) RNA. With this method, 10 anti-HGV positive patients with non A-E hepatitis and 10 healthy subjects were tested. Among 10 patients, GBV-C RNA was detected in 9, 8, 4, 9 patients by the NS-3 (1) primers, the NS3(2) primers, the NS4 primers, the NS5(1) primers and the NS5(2) primers respectively. Control sera from 10 healthy subjects did not reveal GBV-C (HGV) RNA by any set of the primers. These data suggest that the detection rate of GBV-C (HGV) RNA is different in various set of primers, the NS3(1) and the NS5(2) primers are superior to other primers and are more suitable for RT-PCR of GBV-C (HGV) RNA.

DNA Primers↗

PubMed1997

[Determination of icariin in Epimedium koreanum nakai by high performance liquid chromatography].

An HPLC method for determination of icariin in epimedium koreanum nakai was investigated. The results showed that this method was simple, specific and accurate. The recovery was 97.6% and relative standard deviation was 1.2%. About 0.5 g of dried powdered crude drug was weighed accurately, placed in 25 mL of the mobile phase and refluxed on a water-bath for 30 min. After cooling, the solution was decanted. The residue was refluxed twice with 10 mL of the mobile phase. The extract were placed in a 50 mL volumetric flask and diluted to 50 mL with the mobile phase. A 3 microL of the solution was injected into the HPLC system. Linear calibration graphs for icariin were obtained for the concentration ranges of 0.08-0.4 microg. HPLC conditions were used was Shimadzu LC-6A with UV spectrometric detector SPD-6AV; at 270 nm and auto injector SIL-6A. Water-acetonitrile (70:30) as the mobile phase, Shim-pack CLC-ODS column (6.0 mm x 150 mm).

Chromatography, High Pressure Liquid↗