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Biomedical subjects

S S Yang

Publications and source records attributed to S S Yang.

At least 127 records · Page 7Linked to original sources
PubMed1990

[Studies on chemical constituents from Glycyrrhiza paliddiflora Maxim].

Five compounds were isolated from the rhizome of Glycyrrhiza pallidiflora Maxim. Four of them were elucidated by spectroscopic and chemical methods as beta-sitosterol (II), macedonic acid methyl ester (III), 21-dehydro-macedonic acid methyl ester (IV) and 5-hydroxy-4'-methoxy isoflavone (V). VI was isolated for the first time as a natural compound, named pallidifloric acid methyl ester. V is a new compound, named pallidiflorin. Studies of the chemical structure of II are in progress.

Drugs, Chinese Herbal↗
PubMed1990

The unique treatment needs of female substance abusers in correctional institutions: the obligation of the criminal justice system to provide parity of services.

State legislatures and the courts in the United States have not been diligent in guaranteeing female prisoners equal access to rehabilitative programmes when compared with men. Drug and alcohol abuse treatment programmes are fewer and are not tailored to the specific needs of women. This disparity is of particular concern in the light of the growing number of female addicts. The data reveals that a larger portion of women involved with the criminal justice system are substance abusers than are men. In addition, female substance abusers have unique needs which may call for more, rather than equal, resources than male addicts. They have greater medically-related problems, a greater mental health problem, lack of vocational skills and child rearing problems. An understanding of the clinical and social needs of female substance abusers will facilitate the implementation of appropriate programmes and clarify how best to fulfil the legal obligations of the criminal justice system.

Criminal Law↗
PubMed1990

Isolation and characterization of temperature-sensitive mutants of Saccharomyces cerevisiae.

Temperature-sensitive (ts) mutants of Saccharomyces cerevisiae Y-196 were isolated by UV irradiation and/by EMS treatment. There were 163 ts mutants isolated from 66,957 colonies. These mutants were designated as AMY-1 to AMY-163. These ts mutants grew normally at 30 degrees C, but did not grow at 38 degrees C. In an auxanographic study, we showed that AMY-46 was an absolute ts mutant, while AMY-10, AMY-15, AMY-16, AMY-49, AMY-66, AMY-88, AMY-114, AMY-126, AMY-127, AMY-129, AMY-136, AMY-150, AMY-157, AMY-158, AMY-159, AMY-161, and AMY-162 were auxotrophic ts mutants except AMY-16 had cell size 2-42% larger than that of the wild type. Cell aggregation phenomenon was found when the ts mutants were cultivated at 30 degrees C to stationary phase then cultured at 38 degrees C for 4 hr. The budding numbers at 30 degrees C were less than that at 38 degrees C. Mutant AMY-49 had the highest budding number. There was a positive correlation between the growth rate and the average budding number. However, there was a negative correlation between the growth rate at 30 degrees C and the length of long axis of cell or the size of cell.

Mutation↗
PubMed1989

Digoxin-like immunoreactive substances in chronic liver disease.

Digoxin-like immunoreactive substances, which cross-react with digoxin antibody, have been found to have natriuretic effect and Na+,K+-ATPase inhibitory effect. The role of digoxin-like immunoreactive substances in chronic liver disease was studied by radioimmunoassay in 63 serum and 60 urine samples from 58 patients with chronic liver disease and compared with 16 controls. Although the mean serum digoxin-like immunoreactive substances level of compensated chronic liver disease patients (0.06 +/- 0.05 ng per ml, p less than 0.01) was higher than that of controls (0.02 +/- 0.03 ng per ml), only four patients had serum digoxin-like immunoreactive substances higher than 0.10 ng per ml. Mean serum digoxin-like immunoreactive substances level was much higher in patients with decompensated chronic liver disease who had ascites (0.32 +/- 0.17 ng per ml, p less than 0.001), hepatorenal syndrome (0.57 +/- 0.20 ng per ml, p less than 0.001) and hepatic encephalopathy (0.43 +/- 0.20 ng per ml, p less than 0.001). Five patients with recent variceal hemorrhage requiring transfusions and saline infusion had significantly increased serum digoxin-like immunoreactive substances (mean: 0.16 +/- 0.06 ng per ml, p less than 0.001) before the development of clinically detectable ascites.(ABSTRACT TRUNCATED AT 250 WORDS)

Chronic Disease↗
PubMed1989

Fibrinous pericarditis in alcoholic liver disease.

The autopsy data at the University of Southern California Liver Unit was studied during a 6-year period to investigate the relationship of fibrinous pericarditis with liver diseases. We found 18 cases of fibrinous pericarditis in 220 patients with alcoholic liver disease but none in 32 patients with fulminant and subacute hepatitis without alcoholism or in 39 patients with nonalcoholic cirrhosis. Although all the 18 patients with pericarditis had azotemia, 3 patients had pericarditis develop only in mild renal function impairment. These findings suggest that chronic alcoholism may precipitate pericarditis during the hepatorenal syndrome.

Adult↗
PubMed1989

Cavernous lymphohemangioendothelioma of the right atrium--a case report.

The authors report a successful resection of a rare cystic tumor in the right atrium, discovered in an asymptomatic patient with atrial fibrillation. The cystic nature of the tumor was characterized by two-dimensional echocardiogram preoperatively. The site of attachment and movement of the tumor were clearly shown by cine computed tomography preoperatively. The tumor contained numerous endothelium-lined cavernous channels and groups of red blood cells. These features are distinctly different from those of other cystic tumors.

Echocardiography↗
PubMed1989

Treatability of the sex offender: considerations of etiology, pathology, and treatment in repealing sexually dangerous offender statutes.

This article embraces legal and legislative concerns about treatability of dangerous sex offenders; the disease concept of chronic offenders; treatment modalities; an evaluation of treatment; a consideration of treatability. The shortcomings of clinical methods must be borne in mind when evaluating and redesigning sexually dangerous offender statutes.

Aggression↗
PubMed1989

Macromolecule synthesis in temperature-sensitive mutants of methanol-utilizing Hansenula polymorpha.

Temperature sensitive (ts) mutants of methanol-utilizing Hansenula polymorpha NTU-AM-P5 were isolated by UV irradiation, EMS and/or NTG treatment. They grow normally at permissive temperature (PT) 38 degrees C, but can not grow at restrictive temperature (RT) 46 degrees C. From chemical composition analysis, it was found that ts mutants NTU-AM-L2 and NTU-AM-L3 had higher RNA content than the others; while ts mutant NTU-AM-E19 had the highest protein content among the isolated strains. Leucinyl-tRNA synthetases activity was the highest among the twenty aminoacyl-tRNA synthetases in both wild type and their ts mutants. When the cells were shifted from PT to RT for 12 h, total aminoacyl-tRNA synthetase activity decreased in all tested strains. Leucinyl-tRNA synthetase of ts mutant NTU-AM-E10 decreased 91.23%. At RT, it was found that ts mutants NTU-AM-E10 and NTU-AM-E20 were defective in DNA synthesis; ts mutants NTU-AM-E15, NTU-AM-E20, NTU-AM-N37 and NTU-AM-m5 were defective in RNA synthesis; ts mutants NTU-AM-E10, NTU-AM-E20 and NTU-AM-m5 were somewhat defective in protein synthesis; while ts mutants NTU-AM-L2 and NTU-AM-L3 did not belong to any one of the above classifications.

Amino Acyl-tRNA Synthetases↗
PubMed1989

[Observations on the growth dynamics of 4 strains of Toxoplasma gondii in HeLa cells].

Growth dynamics of PP, CN and ZS2 strains of Toxoplasma gondii isolated in China was studied and compared with that of RH strain. HeLa cells were used in this work. It took only 2 min for the organisms of RH strain to infect the HeLa cells when contacting with the cells. By contrast, the CN strain requires 5 min, the ZS2 and PP strains, 10 min. Toxoplasma began its multiplication after a lag time of about 6 h in the HeLa cells. The mean generation time of the 4 strains was assessed by calculating the number of the parasites in the parasitophorous vacuoles at different incubation times and by the linear regression equation. The results showed that the mean generation time was 5.2 h for RH strain, 5.98 h for CN strain, 6.78 h for ZS2 strain and 7.69 h for PP strain. Among the 3 strains of Toxoplasma gondii isolated in China. CN strain was similar to RH strain in their infectivity and proliferation.

Animals↗
PubMed1988

Portal-systemic encephalopathy: alterations in somatosensory and brainstem auditory evoked potentials.

Median somatosensory and brainstem auditory evoked potentials (SEP and BAEP) were studied in 40 patients with liver cirrhosis consequent to chronic viral hepatitis. The patients were divided into 4 groups: group 1 with liver cirrhosis only, group 2 with hepatic failure (HF), group 3 with grade 1 or 2 hepatic encephalopathy (HE), and group 4 with grade 3 or 4 HE. The control group consisted of 10 age-matched normal subjects. The major changes occurred in the median cortical SEP late components (peaks after N20 and P25). From group 1 to group 4, there were progressive prolongation and sequential disappearance of the late components. Those changes in the cortical SEPs were reversible. The subcortical somatosensory and brainstem auditory conductions (SEP N13-N20 and BAEP I-V interpeak latencies) were slightly prolonged in all groups of patients. The present data indicate that SEP may be useful in detecting subclinical HE and in monitoring the clinical course of HE. The present data further indicate that chronic portal-systemic shunting in liver cirrhosis may result in a minimal impairment of cerebral function and sensory conduction in the CNS.

Adult↗
PubMed1988

Analysis of cough/cold products using an adamantyl column.

High-performance liquid chromatographic methods are developed for the determination of active ingredients in several cough/cold preparations. A novel adamantyl phase is used in combination with either totally aqueous or high aqueous hydroorganic mobile phases.

Adamantane↗
PubMed1988

Fixed spinal cord: diagnosis with MR imaging.

Pulsatile motion of the spinal cord was examined with phase imaging techniques. Sagittal images of the spinal cord were obtained at different times of the cardiac cycle in healthy volunteers, as well as in patients in whom the spinal cord either was tethered, was compressed, or contained an intramedullary lesion. Pulsatile velocity changes of the spinal cord, observed on the phase images, were most marked at the cervical-upper thoracic level. Cord motion was found to be significantly decreased in cases in which the cord was either tethered or compressed. Cord enlargement due to an intramedullary lesion generally did not lead to decreased cord motion. Imaging of pulsatile cord motion may be clinically useful in evaluating diseases restricting cord motion or changing the status of parenchymal compliance.

Adult↗
PubMed1988

Transforming DNA sequences of human hepatocellular carcinomas, their distribution and relationship with hepatitis B virus sequence in human hepatomas.

Several related human transforming DNA sequences, hhc, and a putative normal liver homologue, c-hhc, have been molecularly cloned from the genomic DNAs of individual African and Asian hepatomas and from normal liver respectively. hhcM (Mahlavu) and hhcK3 (Korean), but not c-hhc, transformed NIH3T3 cells in DNA-mediated gene transfer assays. Transformed cells were found tumorigenic in athymic NIH Swiss nu/nu mice. In view of recent epidemiological studies implicating hepatitis B virus (HBV) infection early in life as causative for the eventual development of primary hepatocellular carcinoma in humans in Southeast Asia, the Far-East, and certain areas of Africa, we hereby analyzed the relationship between these hhcs and HBV in a survey of 20 hepatomas for DNA sequences homologous to hhcM and HBV by sequential hybridizations against [32p]hhcM and [32p]HBV probes. hhcM related DNA sequence were found highly amplified in 80% of the 20 hepatomas but HBV DNA sequence was rare or low. hhcM lends itself as a marker for human hepatomas. However, overall results indicated that patients with integrated HBV DNA sequences showed high copy number of hhcM sequence. Furthermore, EcoR1-restricted hepatoma DNAs showed that HBV and hhcM DNA sequences resided at different fragments in hepatomas. Our results suggest that HBV contributes to hepatocarcinogenesis probably via an activation mechanism involving possibly an integration or transient interaction of HBV DNA with hepatocyte DNA sequences, leading to recombination and eventual amplifications of the hhcM sequence in Mahlavu.

Animals↗
PubMed1988

Isolation and characterization of temperature-sensitive mutants of Hansenula.

For investigation of the feasibility of obtaining yeast strains with high protein and low nucleic acid content or high nucleic acid and low protein content for industrial production of single cell protein or nucleotide, the methanol-utilizing Hansenula polymorpha NTU-AM-P5 was chosen for isolation of temperature-sensitive mutants. Approximately 70 temperature-sensitive (ts) mutants were obtained. All of the ts mutants increased in cell size and aggregated when they were cultivated at permissive temperature and shifted to restrictive temperature in the late log phase or in the stationary phase. 86.1% of ts mutants had a lower growth rate than that of their wild-type. Only ts mutants, NTU-AM-L2, NTU-AM-E10, NTU-AM-E19, NTU-AM-E25 and NTU-AM-E30 had same or slightly higher than that of their wild-type strain. Cycloheximide at 1 mg/ml inhibited the growth of ts mutant NTU-AM-E19, but inhibited one-third of the other ts mutants, and their wild-type strain. Rifampicin at 0.1 mg/ml had an inhibitory activity on wild-type strain but not on ts mutant NTU-AM-E1. ts mutants NTU-AM-L2 and NTU-AM-E19 converted methanol to cell mass more efficiently than others. The ts mutants divided into two groups. One included absolute ts mutants, such as NTU-AM-E15 and NTU-AM-E20, which did not grow even in enriched media at restrictive temperature; the other group, such as NTU-AM-L2, NTU-AM-L3, NTU-AM-E10, NTU-AM-E19, NTU-AM-N37 and NTU-AM-m5, was auxotrophic ts mutants, which grew slightly in enriched media at restrictive temperature.

Mutation↗
PubMed1988

Induction of B-cell lymphomas in athymic NIH Swiss nu/nu mice.

A B-cell lymphoma was induced in athymic NIH Swiss nu/nu mice by challenging the animals with NIH3T3 cells, previously transfected with a recombinant DNA carrying a human oncogene hhcM, ligated to an SV40 promoter with a neomycin-resistance marker. The gross pathology of the tumor-bearing animal revealed generalized lymphadenopathy and the histopathology indicated widespread infiltration of lymphocytes into organs, such as brain, liver, kidney and lung, in addition to the lymphoid tissues and spleen; the appearance was consistent with diffuse histiocytic lymphoma. Direct immunofluorescence assays with specific typing anti-sera on live cells prepared from spleen and various lymph nodes in short-term culture, suggested the cells were B-cells. This B-cell lymphoma provides an experimental model, not only for studying possible oncogene activation but also for studying the various interactions involved in signal transduction essential for the activation of B-cell proliferation and differentiation.

Animals↗
PubMed1988

Reperfusion-induced arrhythmias: characterization studies with the globally ischemic rat heart.

It has previously been demonstrated in the rat heart, in vivo and in vitro, with regional ischemia, that an asymmetric bell-shaped curve defines the relationship between the vulnerability to reperfusion-induced arrhythmias and the duration of the preceding period of ischemia. The present study sought to establish whether a similar relationship occurred with global ischemia and reperfusion. Using rats from three different sources (two British, one North American) it was observed that, when an appropriate duration of ischemia was selected, reperfusion was capable of eliciting a very high incidence (up to 100%) of ventricular fibrillation and ventricular tachycardia. In the first series of studies an asymmetric bell-shaped relationship was observed such that with reperfusion after 5, 10, 20, 25, 28, 30, 33, 37 and 45 mins 0, 8, 8, 8, 50, 58, 83, 33, 33 and 25% of hearts fibrillated, respectively (12 hearts per group). However, upon repeating the studies with groups of rats from other suppliers or different batches from the same supplier, different results were obtained. Thus, in some study groups a very high incidence of arrhythmia was observed with reperfusion after very short (7.5 mins) durations of ischemia and low incidences were sometimes obtained with reperfusion after 30 mins, a time which, in some study groups, elicited a very high (100%) incidence of severe arrhythmias. These results contrast strikingly with those obtained with regional ischemia where a highly reproducible profile for the incidence of arrhythmias is consistently observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗