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Biomedical subjects

H Z Yang

Publications and source records attributed to H Z Yang.

At least 19 recordsLinked to original sources
PubMed2001

[Detection of telomerase activity level in human non-small-cell lung cancer].

OBJECTIVE: To investigate the telomerase activity in human non-small-cell lung cancer (NSCLC) and to investigate the possibility of telomerase as a tumor biological marker. METHODS: The semi-quantitative assay and expression of PCR-based telomeric repeats amplification Protocol ELISA (TRAP-PCR-ELISA) and PAGE (TRAP-PCR-PAGE) were detected in 15 NSCLC tissues and 15 tumor-adjacent tissues, 3 normal lung tissues. RESULTS: No telomerase activity in 15 tumor-adjacent tissues and 3 normal lung tissues was detected, However, of 15 NSCLC tissues, 13 were positive for telomerase activity with a 86.7% positive rate, telomerase activity was significantly higher in NSCLC than in Tumor-adjacent tissues and normal lung tissues (P < 0.001). CONCLUSION: The results suggest that telomerase is a tumor specific gene marker.

Adenocarcinoma↗
PubMed2001

Involvement of pressure-related mechanism in activation of inducible nitric oxide synthase.

The goal of this study was to clarify the relationship between blood pressure and inducible nitric oxide synthase (iNOS) activity. Different levels of blood pressure were obtained by long-term (six days) intravenous infusion of different concentrations (0.3%-8%) of NaCl solution to normal SD rats. iNOS activity assay and measurement of urinary nitrate/nitrite (UNOx), an index of NO production of the whole body, were carried out by isotope-labeled L-arginine conversion rate measurement and Greiss Reaction respectively. Groups of normotensive and hypertensive rats including normal Wistar rats, normal Sprague-Dawley (SD) rats, high NaCl-induced hypertensive rats (NaHR) and spontaneously hypertensive rats (SHR) were used to detect the changes in iNOS protein under normotension and hypertension by Western blotting. iNOS activity of aorta and kidney tissues and UNOx increased more significantly in hypertensive animals than in the normotensive control ones. Accordingly, iNOS protein in the aortas of NaHR and SHR increased by 149% and 261% respectively. It is suggested that in addition to cytokine and bacterial products etc, blood pressure is also an effective regulatory factor involved in iNOS activation and expression.

Animals↗
PubMed2000

[Study of plasma neuron-specific enolase activity of patients with chronic pulmonary heart disease complicated by pulmonary encephalopathy].

The plasma neuron-specific enolase (NSE) activity in the 15 patients of chronic pulmonary heart disease complicated by pulmonary encephalopathy and 10 chronic pulmonary heart disease without pulmonary encephalopathy (controls) were detected. The results showed that NSE activity in patients with moderate, severe pulmonary encephalopathy were significantly higher than those of patients with mild pulmonary encephalopathy, stable patients and controls. The plasma NSE activity from the patients with pulmonary encephalopathy were negatively correlated with the PaO2 and were positively correlated with PaCO2. This study suggests that plasma NSE activity may reflect the degree of brain damage by chronic hypoxia and remain of CO2 in the patients with chronic pulmonary heart disease.

Aged↗
PubMed2000

[Detection of circulating antigen in urine from mice infected with Toxoplasma tachyzoites by SPA-ELISA].

OBJECTIVE: To explore a simple and convenient immunoassay for early diagnosis of Taxoplasma infection. METHODS: Urine samples collected from three groups of mice infected with different doses of tachyzoites were detected for Taxoplasma circulating antigen (TCA) by dot-ELISA using HRP-SPA as a second antibody (SPA-ELISA). RESULTS: Taxoplasma circulating antigens were detected in all three groups of infected mice in contrast with the normal control group. Taxoplasma circulating antigen was detected on d6 and d3 after infection in mice of light- and moderate-infection groups, respectively. CONCLUSION: SPA-ELISA is a simple and convenient method for early immunodiagnosis of recent Taxoplasma infection.

Animals↗
PubMed1999

Lipophilicity determination of some potential photosystem II inhibitors on reversed-phase high-performance thin-layer chromatography.

The retention characteristics of 25 2-cyano-3-methylthio-3-substituted amine-acrylates are determined using reversed-phase thin-layer chromatography (RP-TLC) with methanol-water mixtures as eluents. The relationship between Rm values and partition coefficients (C log P) are established. The Rm values decrease linearly with increasing methanol concentration in the eluent. The Rm values extrapolated to zero organic modifier concentration (Rm0) in the eluent are highly related to C log P. The Rm0 value can be used to evaluate the lipophilicity of this kind of compound.

Acrylates↗
PubMed1998

A preliminary study of steroid reproductive hormones in human hair.

Nowadays research and clinical studies of human reproductive endocrinology are generally carried out using human blood reproductive hormone assays. However the acquisition of human blood samples has some shortcomings. In search of new approaches, we paid attention to the fact that progesterone can be detected in cow's hair. Consequently we investigated whether or not steroid hormones are measurable in human hair. The results showed that the levels of steroid hormones in hair are not affected by shampoo and do not significantly vary between different segments of hair (i.e. top, middle and basal segments). The menstrual estradiol and progesterone rhythm of female hair is similar to that of female serum. The ratio of hair estradiol to serum estradiol in the female is 41.2% and that of hair progesterone to serum progesterone is 59.0%; the ratio of hair testosterone to serum testosterone in male is 116%. There are significant correlations between hair and serum steroid hormones of healthy human adult: gamma (estradiol) = 0.395 (n = 20), p < 0.05; gamma (progesterone) = 0.440 (n = 22), p < 0.025 and gamma (testosterone) = 0.395 (n = 25), p < 0.05.

Adult↗
PubMed1993

[Isolation of different strains of Toxoplasma gondii from monstera by DNA hybridization].

A specific 32P labelled DNA probe of the cloned DNA fragment (1.1kb) was used in Southern hybridization to determine seven tachyzoites of toxoplasma isolated from dead fetus of malformation during the period of 1986-1989. The results show that seven parasite strains (SH) have identical bands in the same position (2.0kb) compared with RH, Zs2, CN strains, and this provides reliable evidence for identification of toxoplasma.

Abnormalities, Severe Teratoid↗
PubMed1993

[Analysis of proteins and antigens in nine strains of Toxoplasma gondii by means of SDS-PAGE and immunoblotting].

The proteins and antigens of nine strains of Toxoplasma gondii were analyzed by SDS-PAGE and immunoblotting. These strains including RH strain, Zs-2 strain, CN strain and SH1, SH2, SH3, SH4, SH5, SH8 strains, were obtained from other laboratories or isolated from deformity fetus in our laboratory. SDS-PAGE analysis revealed that these strains were very close in the major bands of proteins and differences were observed only in part. There were common components in antigens of all strains using IgG antibody prepared from high-titre rabbit antisera raised against RH strain of Toxoplasma.

Animals↗
PubMed1993

[Detection of circulating antigen in urine from mice infected with Toxoplasma tachyzoites].

Urine samples collected from three groups of mice infected experimentally with different numbers doses of Toxoplasma trophozoites were detected for the presence of Toxoplasma circulating antigen by using fast ELISA. The results showed that presence of circulating antigen in all three infected groups of mice in comparison with the normal control group. Toxoplasma circulating antigen was detected on days 5, 4 and 3 after infection in light-, moderate- and heavy-infection groups, respectively. The concentration of circulating antigen was on a parallel with the duration of infection. Western blot analysis of the Toxoplasma circulating antigen in urine revealed the existence of seven specific bands with molecular weights of 75, 67, 55, 43, 30, 28 and 22 kDa.

Animals↗
PubMed1992

Construction of a genomic DNA library of the Toxoplasma gondii ZS2 strain, screening of specific clones, and DNA diagnosis of toxoplasmosis.

We have constructed a genomic DNA library of the Toxoplasma gondii ZS2 strain and isolated a specific cloned DNA sequence from this organism. The restriction map of this cloned 1.1-kb DNA fragment was analyzed. Southern and dot-blot analyses showed that the 32P-labeled DNA fragment hybridized to parasite DNA, to DNAs from peripheral blood leukocytes and the thymus of baby pigs that were artificially infected with T. gondii, and to DNAs of T. gondii-positive anencephalic and hydrocephalic fetuses. It did not hybridize with DNA from controls, (i.e., normal human and baby pig peripheral blood leukocytes, spleen of normal mice, Plasmodium falciparum, Pneumocystis carinii, and pBR322). As few as 100 T. gondii parasites or 500 pg of purified DNA from T. gondii can be detected by dot-blot hybridization. This probe method was specific and sensitive, and has been used successfully in detecting various clinical cases of toxoplasmosis with T. gondii.

Animals↗
PubMed1992

[Effect of compound and minor prescription of heat-nature products radix Aconiti lateralis preparata, rhizoma Zingiberis and cortex Cinnamomi on the sympathetic nervous system, adrenal gland, TSH and LH].

The effect of compound and minor prescriptions of Radix Aconiti Lateralis Preparata, Rhizoma Zingiberis and Cortex Cinnamomi on sympathetic nervous system, adrenal gland, TSH and LH of rats was studied. Results showed that both prescriptions made the heart rate quicken, estrous cycle shorten, improved the adrenal cortex hormone and promote TSH and LH synthesis and secretion. The two Heat-nature products (Radix Aconiti Praeparata and Rhizoma Zingiberis) may be used instead of all the three products to make a Heat Syndrome animal model.

17-Hydroxycorticosteroids↗
PubMed1992

[Diagnosis of toxoplasmosis by polymerase chain reaction].

Based on the partial sequences of the specific DNA cloned fragment from T. gondii (ZS2 strain) a specific primer of the oligonucleotide for the Toxoplasma gondii DNA sequence has been designed and synthesized in our laboratory. The method of the DNA diagnosis for toxoplasmosis by polymerase chain reaction (PCR) has been established. A specific amplified band was shown in the PCR products from DNAs of T. gondii and seven manifold terata. The DNAs from the peripheral blood leukocytes of fifty normal individuals and seventy-five patients as infants with hepatitis syndrome and pregnant women with previous abnormal birth histories were diagnosed by PCR. Among the seventy-five diagnosed cases, ten were positive. The normal individuals all were negative. Using 32P-cloned T. gondii specific DNA fragment as probe and Southern blot assay, the results showed that the probe only hybridized to the specific amplified DNA bands, but did not hybridize to the amplified DNA products of negative cases. Our PCR method is a rapid, highly specific and sensitive one for detecting toxoplasmosis as compared with DNA probing, immunoassay and animal inoculation.

Anencephaly↗
PubMed1992

[Toxoplasmic retinochoroiditis].

Retinochoroiditis is a frequent ocular lesion in toxoplasmosis. It may be severe, and even lead to blindness. Sixteen cases of toxoplasmic retinochoroiditis verified through IFA were presented in this paper. Among these cases, 1 was of the multifocal type, its appearance being similar to that of the Coats disease; while the other 15 were of the focal type resembling to the central exudative retinitis (Rieger disease) or retinochoroidal scar. Serological finding of all the cases showed a positive IFA titer of > 1:80. A combination of pyrimethamine and sulfadiazine as well as spiramycin in addition to dexamethasone had been administered and proved effective. Since toxoplasmosis mostly occurs as latent and examination of the eye cannot differentiate from other causes of retinochoroiditis, so such clinical report of toxoplasmic retinochoroiditis was rare with particular reference in our country. The authors claimed that any individual presenting with retinochoroiditis suspected of toxoplasmosis should be subjected to serologic antibody test for establishing diagnosis.

Adolescent↗
PubMed1990

[The effect of various cleansing methods for total fiber optic colonoscopy].

It is a fact that there are recent increasing trends of incidence of the colorectal carcinoma among other colorectal diseases. In such trend, the early detection remain to be most important by the air contrast barium enema and total fiber optic colonoscopy There are several ways to prepare the colon for barium enema and fiber optic colonoscopy which include several agents. The mechanical cleansing have been used most frequently since Brown's method was adapted to be most perfect for colon cleansing. The ideal laxatives and enema solutions were limited to adequate dose, it's effectiveness, patient's diet and bowel habit, minimal side effect, low cost and simple to perform. In order to compare the effectiveness of various cleansing solutions, six experimental methods were formed as shown; 1. normal saline enema, 2. castor oil with normal saline enema, 3. castor oil with soapsuds enema, 4. magnesium citrate with normal saline, 5. magnesium citrate with soapsuds enema and 6. ingestion of Golyetly solution. The authors have compared and determined the degree of cleanliness by an experienced endoscopist The total number of patients was 247, age distribution was 43 +/- 15 years old, and sex distribution was 133 males and 114 females. The grade I and II represented no difficulties at performing the fiber optic colonoscopy+, but grade III and IV had some difficulties, even unable to perform the fiber optic colonoscopy. The effectiveness the cleansing agents, represented with grade I and II was 95.9% (47/49) in method 6, 93.2% (54/58) in method 2, 83.3% (30/33) in method 3, 70.0% (28/40) in method 5, 66.7% (16/24) in method 1, and 45.7% (18/40) in method 4. Method 2 and 6 were the most effective in normal bowel habit patients. In constipated patients, method 6 was the most effective and all method except method 4 were effective in diarrhea patients. The degrees of less mucosal irritation by various bowel cleansing method were in the order of method 6(100%), 1(100%), 5(74%), 2(69%). In subjective symptoms and cleansing groups, abdominal distension, pain, nausea and vomiting were complained, and that's subject symptoms were in the order of method 3(88.9%), 6(79.6%), 1(75%), 5(72.5%), 2(72.4%), 4(67.5%). In conclusion, we believe that the Golytely of the mechanical cleansing solution for fiber optic colonoscopy was the most effective, but others depended on the patient's condition and bowel habit.

Adult↗
PubMed1990

[Construction of a genomic DNA library of Toxoplasma gondii (ZS2 strain), screening of specific clone and DNA diagnosis of toxoplasmosis].

We have constructed a genomic DNA library of Toxoplasma gondii (ZS2 strain) and screened out a specific DNA sequence for T. gondii. The restriction map of the cloned DNA fragment (1.1kb) was analysed. The Southern and dot-blot analyses showed that the 32P-labeled cloned DNA fragment hybridized to the parasite DNA, DNAs from peripheral white blood cells and thymus of baby pigs artificially infected with T. gondii and DNAs of T. gondii- positive anencephalus and hydrocephalus, but did not hybridize to DNAs from controls, i. e., normal human and baby pig peripheral white blood cells, spleen of normal mouse, Plasmodium falciparum, Pneumocystis carinii and pBR322. As few as 100 T. gondii parasites or 500pg purified DNA from T. gondii can be detected by dot blot hybridization. This established DNA probe method was specific and sensitive and has been successfully used in detecting various cases infected with T. gondii.

Animals↗