Search PubMed⌕ Search

Biomedical subjects

H Yang

Publications and source records attributed to H Yang.

At least 793 records · Page 44Linked to original sources
PubMed1995

Establishment of a leukemic lymphocyte culture from human aqueous humor.

We have recently developed new techniques for culturing chronic lymphocytic leukemia (CLL) lymphocytes from human aqueous humor. We used leukemic lymphocytes collected from the aqueous humor of a patient with CLL and leukemic glaucoma. We grew these leukemic cells in combination with a feeder cell layer and other technical refinements. Microscopy and immunoassay indicate success in obtaining a homogenous population of B-type CLL cells through the 12th passage of the culture. No significant effect on cell growth was found with either of two mitogens (PWM and PHA), or between culture with and without autologous serum. Our new techniques for culturing leukemic cells derived from the aqueous humor provide a reliable resource for the study of chronic lymphocytic leukemia lymphocytes and leukemic glaucoma.

Animals↗
PubMed1995

Phenopyrrozin, a new radical scavenger produced by Penicillium sp. FO-2047.

A new radical scavenger, named phenopyrrozin, was isolated from the culture broth of Penicillium sp. FO-2047. Phenopyrrozin was purified from whole broth solvent extraction, silica gel chromatography, and HPLC. The structure of phenopyrrozin was elucidated as 5,6,7,7a-tetrahydro-2-hydroxy-1-phenyl-3H-pyrrolizin-3-one. The IC50 of phenopyrrozin against lipid peroxidation induced by Cr2K2O7 was 73 micrograms/ml. Phenopyrrozin also reduced chromosomal aberrations induced by paraquat.

Animals↗
PubMed1995

[An outline of spreading of Western mediciine into Yantai in modern age].

At the turn of the last century, side by side with the infiltration of religious culture from Western countries, western medicine spread into Yantai. The religious force, headed by American Presbyterian Mission, carried out charitable activities in the process of preaching and laid down the foundation for western medicine rooted in Yantai by establishing schools, education and training followers. They cultivated local physicians by first setting up clinics which had later transformed into hospitals. These are their major measures for building bases for spreading Christianity by foreigners. The Temple Hill Hospital set up by the American physician Oscar F. Hills in Yantai was a successful example of mutual promotion of missionary and medical activities which pushed forward the spreading and development of western medicine in Yantai.

China↗
PubMed1995

[Induced expression of whiG, a gene crucial for sporulation of Streptomyces coelicolor].

whiG gene has been subcloned into Streptomyces expression vector pAK203 containing inducible promoter tipA. The expression of whiG gene promoted the spore formation of S. coelicolor J1501 and recovered the sporulation ability of whiG-deficient S. coelicolor C71. Increased amount of whiG gene product was detected by Western blot hybridization after induction of thiostrepton. It will be helpful for the future study of in vitro transcription of whiG-dependent promoters.

Gene Expression Regulation, Bacterial↗
PubMed1995

Expression of muscarinic receptor subtype mRNA in the human ciliary muscle.

PURPOSE: To investigate the expression of the muscarinic receptor (mAChR) subtypes (m1, m2, m3, m4, and m5) in the human ciliary muscle. METHODS: cDNA probes specific for the m1 to m5 subtypes were used to characterize the expression of subtype-specific mRNAs by in situ hybridization and Northern blot analysis on a cell line derived from human ciliary muscle tissue (H7CM), sectioned tissue from four donors, and fresh human ciliary muscle tissue from three donors. RESULTS: Messenger RNA for m2, m3, and m5 was detected in situ hybridization and Northern blot analysis in the H7CM cell line and in human ciliary muscle tissue from the donors. In human ciliary muscle tissues, the expression of mRNA of the m2 and m3 subtypes was more prominent in the circular portion than in the longitudinal portion. In contrast, mRNA for the m5 subtype was greater in the longitudinal portion than in the circular portion. Additionally, Northern blot analysis showed that m1 and m4 were expressed in ciliary muscle tissue. CONCLUSION: These studies show that the human ciliary muscle definitely expresses the mRNA of subtypes m2, m3, and m5, and may also express the mRNA of m1 and m4. Although the expression of mRNA for the m2, m3, and m5 subtypes differed between the circular and longitudinal portions of the ciliary muscle, the strong expression of all three subtypes of muscarinic receptors by both portions demonstrates that the differential distribution of muscarinic subtypes probably is not responsible for the dissociation between outflow facility and accommodation that can occur under certain conditions.

Adult↗
PubMed1995

[Sensitivity of Plasmodium falciparum to seven antimalarials in China-Laos border].

The sensitivity of P. falciparum to chloroquine (CHL), piperaquine (PIP), artesunate (ATS), dihydroartemisinine (DAT), artemether (ATM), arteether (ATE) and pyronaridine (PRN) were assayed by in vitro microtechnique in China-Laos border in 1992. The resistance rates of isolates from the south of Yunnan of China in the border were 97.0%, 96.4%, 12.5%, 16.0%, 6.3% and 34.5%, respectively; ID50 were 119.0, 320.0, 7.2, 5.4, 295.0, 74.4 and 31.9 nmol/L, ID95 were 625.0, 2426.0, 42.2, 36.6, 767.0, 371.1 and 325.2 nmol/L. The resistance rates of isolates from the north border of Laos were in order 9/10, 8/10, 1/5 to CHL, PIP, PRN, ID50 were 114.0, 166.9, 16.4 nmol/L, ID95 were 570.0, 631.1 and 107.7 nmol/L. All the isolates from Laos were sensitive to ATS, DAT, ATM and ATE. ID50 were 5.0, 4.4, 91.6 and 56.7 nmol/L, ID95 were 23.4, 11.1, 3276.1 and 223.9 nmol/L, respectively. The results indicate that P. falciparum in the border was highly resistant to CHL and PIP, while most of the isolates were susceptible to the other 5 of the above-mentioned drugs. A comparison between the isolates from China and Laos showed that there was no significant difference in resistance degree to CHL but the sensitivity of isolates from China to other 6 drugs was lower than those from Laos.

Animals↗
PubMed1995

[Study on hsp 70 gene level in cultured smooth muscle cells and aorta from SHR and WKY rats].

Using nucleic hybridization, we investigated hsp 70 gene level on: 1. aorta on spontaneous hypertension rats (SHR); 2. cultured SHR and WKY smooth muscle cells (SMCs) induced by heat shock; 3. cultured SHR and WKY SMCs in 6 weeks and 3 months. The results indicated that hsp 70 mRNA increased in aorta of SHR (6 weeks), in cultured SHR SMCs as compared with WKY SMCs induced by heat shock (42 degrees C, 15 minutes), and in cultured SHR SMCs (6 weeks) as compared with WKY SMCs (6 weeks). Meanwhile, hsp 70 mRNA of cultured SHR SMCs in 6 weeks was higher than that in 3 months. We postulated that overexpression of hsp 70 of cultured SMCs and aorta of SHR in 6 weeks might be related with cellular proliferation during the development of hypertension and that the cultured SHR SMCs might be sensitive to heat shock.

Animals↗
PubMed1995

[Multiple organ injury after delayed fluid resuscitation in severely scalded rats: role of oxygen free radicals].

Sixty gnotobiotic rats with 5 strains of bacteria in intestine were randomized to 4 groups: (1) Sham injury group (controls, n = 6). (2) Early fluid resuscitation (EFR) group (n = 24), receiving fluid resuscitation (Parkland formula) immediately after scald (40% TBSA, third degree). (3) Delayed fluid resuscitation (DFR) group (n = 24) receiving resuscitation 6 hours later after scald. (4) Treatment group (n = 12) receiving DFR and the therapy of VitC and VitE. At 8, 24, 48 and 72 hours after injury, the animals (n = 6, at each point) were sacrificed and the content of oxygen free radicals (OFR), SOD,GSHPx and MDA in the heart, liver, kidney and lung were determined. Morphological Changes of organs, PaO2, PaCO2 and the content of serum CPK, LDH, GPT, GOT, BUN and Cr were also examined. Both EFR and DFR groups demonstrated elevated content of OFR and MDA and reduced content of SOD and GSHPx in their organs. Morphological and serological changes were also observed. All these changes were more obvious in DFR group than in EFR group. After the treatment of VitC and VitE, the changes were ameliorated. Our results suggested that DFR induced the production of OFR, resulting in lipid peroxidation and that OFR injury might be one of the main factors in the pathogenesis of multiple organ injury after DFR.

Animals↗
PubMed1995

Hypercapnic acidosis and dimethyl amiloride reduce reperfusion induced cell death in ischaemic ventricular myocardium.

OBJECTIVE: The aim was to investigate the effects of slowing the recovery of ischaemia induced intracellular acidosis with hypercapnic acidosis or dimethyl amiloride (DMA) on the extent of reperfusion induced cell death. METHODS: Isolated arterially perfused rabbit papillary muscles and septa were suspended in a controlled atmosphere and perfused with a modified Tyrode solution containing erythrocytes and trypan blue (500 microM). Ischaemia was produced by arrest of perfusion and withdrawal of atmospheric O2. Extracellular pH of the muscle during reperfusion was controlled by adjusting the pH of the perfusate (pH 6.6 or pH 7.6 with and without DMA 20 microM) and changing the PCO2 of the chamber atmosphere. After 30 min of reperfusion following 30 min (group A) or 60 min (group B) of ischaemia, papillary muscles were fixed with paraformaldehyde. Cell death was assessed by trypan blue staining of nuclei in histological sections of the papillary muscles. RESULTS: The magnitude of cell death was greatest after reperfusion with pH 7.6 as measured by the percentage of nuclei staining with trypan blue (15.1% in group A; 41.8% in group B). By contrast, reperfusion at pH 6.6 reduced cell killing (group A, 3.6%; group B, 7.2%). Reperfusion at pH 7.6 with DMA (20 microM) also reduced trypan blue uptake (group A, 2.8%; group B, 3.8%). Despite the attenuation of cell death afforded by acidosis or Na+/H+ exchange inhibition, significant swelling of the extracellular space and microvascular injury was noted. CONCLUSIONS: Hypercapnic acidosis and Na+/H+ exchange inhibition during reperfusion attenuate lethal reperfusion injury to ventricular myocardium and extend to the intact myocardium the concept of the "pH paradox" in which recovery of intracellular pH after reperfusion is a precipitating factor in lethal cell injury.

Acidosis↗
PubMed1995

Experimental renal artery stenosis and angioplasty. The mechanism of the angioplasty.

The mechanism of percutaneous transluminal renal angioplasty (PTRA) was studied in 18 dogs. The dogs were divided into two groups. Seven dogs were in the early group and eleven were within 1-3 weeks after PTRA. A 4/0 resorbable chronic catgut was used to ligate subtotally the renal artery to create fibromuscular dysplasia. PTRA was performed after renal artery stenosis for 6-8 weeks. The changes of ultrastructure of renal artery were studied. A contrary orientation balance hypothesis was proposed to explain the mechanism of PTRA.

Angioplasty, Balloon↗
PubMed1995

Extensive wound excision in shock stage in patients with major burns.

To stop excessive plasma loss, alleviate noxious effects of devitalized tissues on the body and shorten the hospitalization time, we performed extensive escharectomy during the shock period in extensively burned patients. Group A consisted of 21 patients aged 9-45 years (26.1 +/- 7.9 years), with a mean total burn area of 63.2% +/- 18.1% TBSA, and full-thickness injury involving 35.9% +/- 19.6% TBSA. The first escharectomy was done at 24.1 +/- 13.9 hours postburn, and excision area averaged 32.3% +/- 6.7% TBSA (24%-46%). In 15 of them, Swan-Ganz catheter was introduced to monitor the hemodynamic changes. It was found that RAP, PAP, PAWP, ABP, HR, CO and CI were all stable during and after the operation. Group B consisted of 29 patients aged 11-50 years (30.4 +/- 11.7 years), in whom escharectomy was begun 4-5 days postburn. The mean healing time of the patients in group A was 33.1 days, shorter than that of group B patients (40.1 days). The duration of hemoconcentration was shorter in group A. The amount of blood transfusion was almost 700 ml less in group A during the first two weeks. Less antibiotics were used with fewer visceral complications in group A. We believe that escharectomy during the burn shock stage is feasible.

Adolescent↗
PubMed1995

Epidemiology of Helicobacter pylori infection in the People's Republic of China.

This paper presents a general review of the studies on the epidemiology of H. pylori infection in China. Among 3,519 dyspeptic individuals presenting for endoscopy, H. pylori detectable rate was 61.2%. A higher prevalence of infection was found in patients with peptic ulcer. The prevalence of gastric metaplasia was 82.5% in patients with duodenal ulcer, 53.1% in duodenitis and 34.5% in normal duodenal mucosa. H. pylori infection is significantly more common in gastric cancer patients (58.9%) than in the matched controls (42.5%). Endoscopic studies performed on asymptomatic volunteers aged 10-25 showed that the prevalence of gastritis and H. pylori was 45%-84% and 42%-67% respectively. Large scale prospective studies of the possible role of H. pylori in gastric cancer in populations with various gastric cancer mortality rates using ELISA assays showed a significant geographical association between gastric cancer mortality and the prevalence of H. pylori infection. H. pylori infection is acquired at an earlier age and has a higher prevalence in the high gastric cancer risk areas than in the low risk areas. H. pylori was detected in human saliva and dental plaque by PCR. H. pylori-like organisms were successfully isolated by culture and detected by nested PCR in the gastric mucosa of pigs and cats. Intrafamilial clustering of H. pylori infection was observed.

China↗
PubMed1995

Beneficial effects of NTG on left ventricular volumes and systolic function in patients with myocardial infarction.

The effect of sublingual administration and intravenous drip of nitroglycerin (SLNTG and IVNTG) on left ventricular volumes (LVVs) were studied and systolic function was quantitatively assessed with two-dimensional echocardiography (2DE) in 28 patients with myocardial infarction (MI), including 13 cases without heart failure (MI-NHF) in one group and 15 with heart failure (MI-HF) in another. The results showed that after SLNTG and IVNTG in both groups the heart rate (HR) increased significantly (P < 0.05-0.001); the systolic blood pressure (SBP) decreased significantly (P < 0.05-0.001); the diastolic blood pressure (DBP) was not significantly changed (all P > 0.05); the left ventricular end-diastolic and end-systolic volumes (EDV and ESV) both significantly reduced [EDV: decreased by 5.8-11.6% (-13.2-19.0 ml), P < 0.05-0.001; ESV: decreased by 9.6-16.6% (-8.6-17.3 ml), P < 0.05-0.001)]; the left ventricular ejection fraction (LVEF) all significantly elevated (increased by 6.6%-9.4% (3.2%-3.4%), P < 0.05-0.001] except in MI-NHF group after IVNTG; the segmental EF of normal and hypokinetic segments also significantly increased (P < 0.05-0.001). The results suggest that NTG could beneficially reduce left ventricular EDV and ESV; and improve or strengthen its global and segmental systolic function in MI patients, particularly noticeable in patients with heart failure.

Blood Pressure↗
PubMed1995

[Monitoring of lead content in foodstuff in China].

Lead contents in six kinds of foodstuff in China were monitored in 1992. Six hundred and three specimens of food were collected from the markets in Beijing, Shanghai, Jiangsu, Sichuan and Guangdong. Results showed that 96.2% of cereals, 84.4% vegetables, 97.6% dairy products, 96.0% eggs and, 100% meat and fish met the national food hygienic standards for lead allowable content. Daily dietary intake of lead of residents in six areas of China was lower than the provisional standard for Daily Allowable Intake of lead set by World Health Organization.

Animals↗
PubMed1995

Acute gastritis associated with infection of large spiral-shaped bacteria.

We report a case of gastric colonization of large spiral-shaped bacteria in a patient with acute gastritis. Endoscopy showed an acute erosive and hemorrhagic gastroduodenitis. Histopathological examination of antral biopsies revealed intense neutrophil infiltrates with microabscesses. Numerous large spiral-shaped bacteria were seen in the Gram-stained smear of the gastric biopsy. The patient was treated with colloidal bismuth subcitrate and cimetidine. Biopsy taken after treatment showed resolution of infection and histological gastritis. The results provide further evidence that large spiral-shaped bacteria are another infective cause of acute neutrophilic gastritis in humans.

Acute Disease↗
PubMed1995

Biological effects of carbon ions with medium energy on plant seeds.

The biological effects of 46.6 MeV/u 12C6+ ions on four kinds of plant seeds were studied at the Heavy Ion Research Facility in Lanzhou (HIRFL), Institute of Modern Physics (IMP), Academia Sinica. The results show that germination of the seeds is inhibited by exposure to ions. In root tip cells of irradiated seeds, a great variety of chromosomal aberrations were observed. Sensitivities in terms of inhibition of germination and induction of chromosomal aberrations in the four species are correlated.

Carbon↗
PubMed1995

Fluorescence spectroscopic study of the interaction of adenine and nucleotide with trichosanthin.

Trichosanthin (TCS) is an N-glycosidase that can attack the 28s rRNA of the ribosome at a highly conserved adenine residue. The interactions of adenine and its derivative nucleotides with TCS are reported. The fluorescence of Trp 192 of TCS is sensitive to the proximity of adenine, and produces a marked red shift indicative of trytophan in a more hydrophilic environment. By contrast AMP and ATP quench the maximal emission at 328nm. The binding of the adenine and ATP with TCS result in lower tryptophan accessibility to the quencher acrylamide, but higher tryptophan accessibility to the quencher iodide, while AMP caused higher tryptophan accessibility to acrylamide, and lower tryptophan accessibility to iodide. Also, the binding of nucleotides induces tryptophan heterogeneity in the protein. These findings lead us to propose that binding of nucleotides and adenine base cause different microenvironmental changes of the tryptophan residue, and Trp 192 may be involved in the active site of TCS.

Adenine↗