Biomedical subjects

W Gao

Publications and source records attributed to W Gao.

At least 109 records · Page 6Linked to original sources

PubMed1999

[Effects of space flight on medicinal plant Agastache rugosa (Fisch. et Mey.) O. Ktze].

OBJECTIVE: To substantiate the effect of space conditions on medicinal plants. METHODS: The seeds of Agastache rugosa were set up in retrievable satellites. After returning to earth, the changes of isozymes of peroxidases, esterase and soluble proteins were studied. RESULTS: The peroxidase activity and protein content of the weightless group were a little lower than those of the earth controlled group, while these two items of the hit group were higher than those of the earth controlled group. The electrophoresis patterns of isoperoxidases and isoeasterase of these three groups, as well as the protein patterns of the weightless group and the earth controlled group were found alike. But the protein patterns of the hit group were different from those of the other two groups. CONCLUSION: The effect of weightlessness is smaller than that of the high energy heavy ions on Agastache rugosa. Different plants have different susceptibility to space conditions.

China↗

PubMed1999

Development of a universal immunoenzyme quantitative assay for detecting amplified products of nucleic acid and its preliminary application in hepatitis C virus.

OBJECTIVE: To develop a universal quantitative immunoenzyme assay (EIA) for detecting amplified products of nucleic acid and its application in hepatitis C virus (HCV). METHODS: The appropriate cycle number of amplification was selected to stop polymerase chain reaction (PCR) before the "plateau stage". At the same time, primers HCV (3) of the second PCR were modified with biotin so that the amplified products were labeled. The products were diluted and subsequently added to the streptavidin-coated wells, and the biotinylated products were captured, followed by denaturation of NaOH, and non-biotinylated strands were removed. Hybridization was performed by adding the specific probe labeled with fluorescein. Finally antifluorescein horse radish peroxidase (HRP) conjugates were added, after washing, 3, 3', 5, 5',-tetramethylbenzidine (TMB) was added to the wells and then measured on a microplate reader. RESULTS: EIA detection of amplified products of HCV showed that this assay was rapid, sensitive, specific and accurate. Correlation between the initial number of viral template and the EIA of amplified products was good. We also prospectively investigated the response to interferon in five patients with HCV coinfection. Results showed that this assay could be used as a guidance to the clinical therapy in directing the use of antiviral drugs. CONCLUSIONS: This assay could be widely used as a universal technique for the quantitative detection of amplified products of all nucleic acid (such as virus, bacterium) and other human genes (such as HLA B27), it has vast vistas.

Hepacivirus↗

PubMed1999

Hyperhomocysteinemia and hyperlipidemia in coronary heart disease.

OBJECTIVE: To examine the relationship between coronary heart disease (CHD) and serum lipid, plasma homocysteine (HCY) as well as the factors related to HCY metabolisms. METHODS: The mutation of the 677C-->T transition of 5, 10-methylenetetrahydrofolate reductase (MTHFR) was determined by PCR-based assay. Whole-blood and plasma folate and plasma vitamin B12, as cofactors of MTHFR, were determined by radio-immunologic assay. Plasma HCY was determined by HPLC. RESULTS: Patients with CHD had elevated plasma HCY concentrations (17.38 +/- 1.94 mumol/L vs 10.25 +/- 1.57 mumol/L, P < 0.01). In patients with myocardial infarction (MI) and family history (FH) of CHD, plasma HCY were elevated even higher (P < 0.05). Plasma HCY concentrations had significant non-linear inverse correlation with plasma folate and B12 concentrations, i.e. the lower the serum folate or B12 concentrations, the higher the plasma HCY concentrations (P < 0.01). Patients with homozygous mutants had higher plasma HCY concentrations. Patients with CHD had increased serum Chol and LDL-C and Apo-B levels (P < 0.01, P < 0.05 and P < 0.05 respectively). But plasma HCY concentrations had no correlation with serum lipid levels. 24.1% of the patients had high lipid and high HCY level, 25.9% had high lipid level and normal HCY level, 20.4% had normal lipid and high HCY level, and 29.6% had normal lipid and HCY level. CONCLUSIONS: HCY may have strong association with the genesis of CHD. Low plasma folate and B12 concentrations may induce Hyperhomocysteinemia [HH(e)]. Plasma HCY concentrations have no correlation with serum lipid levels, so HCY may be an independent risk factor. CHD may be induced by different mechanisms and can be classified into hyperlipidemia, HH (e) and normolipidemia, and normohomocysteinemia.

5,10-Methylenetetrahydrofolate Reductase (FADH2)↗

PubMed1999

[Effects of low-dose tritiated water on the developing central nerve system and their mechanisms].

OBJECTIVES: To provide experimental data for evaluating tritium risk of nuclear-energy plant and instituting safety protection standard of nuclear effects of low-dose tritiated water(HTO) on the developing central nerve system. METHODS: Pregnant adult C57BL/6J strain mice and Wistar rats were irradiated with beta-rays from HTO by a single intraperitoneal injection on the 12.5th and 13th day of gestation. The activity of HTO was (x 10(4) Bq/g. B.W) 24.09, 48.18 and 144.54, respectively. Neurobehavior and learning and memory ability were tested. Ca2+ currents of hippocampal neurons were examined by patch-clamp. Apoptosis of brain cells was detected morphologically and biochemically by DNA electrophoresis. SDS-PAGE and Western blotting were used to detect P53 protein in the cultures. RESULTS: After irradiation with beta-rays from HTO in utero, the offspring showed hyperactivity in their young age period and then showed depression-hypoactivity in adulthood. The exposed animals had difficulties in both learning and memory retention and the developing neurons of the central nerve system showed lower Ca2+ currents, higher number of apoptosis, a typical "ladder pattern" DNA and increasing P53 protein. CONCLUSIONS: Lower Ca2+ currents, higher number of apoptosis of brain cells and abnormal expression of P53 protein were the substance basis of the damage of central nerve system caused by tritium.

Animals↗

PubMed1999

[Analysis of mandibular movement and functional classification for malocclusion patients].

OBJECTIVE: To classify the paths of mandibular movements of patients with malocclusion. METHODS: 223 patients were examined clinically and mandibular Kinesiograph(MKG) was applied. RESULTS: Each kind of malocclusion has its corresponding characteristic paths of mandibular movement. The paths of mandibular movements of patients with the same class of malocclusion are similar. It was also found that the mandibular movement was related not only with occlusion but also with jaws, muscles, and joints. Meanwhile, they affect each other. CONCLUSION: Functional malocclusion classification includes functional class I, II, III and IV malocclusion.

Adolescent↗

PubMed1999

[The features of coronary angiography in coronary heart disease with non-insulin-dependent diabetes mellitus].

OBJECTIVE: To study the clinical and angiographical characteristics of coronary heart disease (CHD) in CHD patients with non-insulin-dependent diabetes mellitus (NIDDM). METHODS: The study was carried out by case control analysis of the clinical manifestations and the data from cine selective coronary angiography. RESULTS: CHD patients with NIDDM tended to have multiple cardiovascular risk factors. It is likely that NIDDM contributed more to dyslipidemia in the female than in the male. Unstable angina pectoris was found more frequently in CHD patients with NIDDM than in those without. The female CHD patients with NIDDM were more frequently afflicted with myocardial infarction. Moreover, CHD patients with NIDDM had much greater extent of coronary vessel involvement and more diffuse vascular lesion. CONCLUSION: The clinical and angiographical findings are quite different in CHD patients with and without NIDDM. The lesions in the coronary arteries tend to be more severe and diffuse in patients with NIDDM.

Adult↗

PubMed1999

[Diagnosis and treatment of gastric carcinoid tumors].

OBJECTIVE: To investigate the method for surgical diagnosis and treatment of gastric carcinoid tumors. METHODS: Clinicopathologic features of 9 patients with gastric carcinoid tumors were analyzed retrospectively. The patients were confirmed by biopsy at endoscopy or surgery. RESULTS: Eight of the 9 patients underwent elective operation, 6 showed gastric carcinoid tumors before operation found by biopsy at endoscopy. Five tumors were malignant and 4 benign. Two patients showed malignant carcinoid syndrome, but 5-HT and 5-HIAA were normal. CONCLUSIONS: Benign or malignant gastric carcinoid tumor depends upon tumor size, local lymph node invasion and distant metastases. The prognostic factor is based on benign or malignant tumors. Operation may be the first choice for such patients.

Adult↗

PubMed1999

[Early use of Chinese drug rhodiola compound for patients with post-trauma and inflammation in prevention of ALI/ARDS].

OBJECTIVE: To evaluate the effects of the Chinese drug rhodiola on the preventive treatment of acute lung injury (ALI) caused by post-traumatic/inflammatory and thoracic-cardiovascular operations. METHODS: 104 patients who coincide with their diagnosis and standard scale were divided randomly in to single number groups A(1), B(1), C(1) and D(1) (early preventive treatment group EG) and double number groups A(2), B(2), C(2) and D(2) (control group CG). The treatment of primary disease both in EG and CG was similar, but in EG four grams of rhodiola compound (RCO) were used every day for a period of 3-15 days since admission and 5-7 days after operation. The indicators related to ALI in each groups were measured. RESULTS: PaO(2), AaDO(2) and hemorheology were significant in EG than in CG (P < 0.05) or (P < 0.01). The complication rate of ARDS was decreased about of 50.0% in EG than in CG. CONCLUSIONS: Early use of RCO may protect against major risk factors of ALI/ARDS caused by massive trauma/infection and thoracic-cardio-operations.

Adolescent↗

PubMed1999

[Posttraumatic or inflammatory acute respiratory distress syndrome on high altitude area: a retrospective analysis of 94 deaths due to ARDS/MOF].

OBJECTIVE: To determine the characteristic predictors of acute respiratory distress syndrome (ARDS) in the high altitude area of China. METHODS: According to the diagnostic criteria of ARDS, 2 325 cases were screened in the recent 10 years. Except malignant tumors, cardio-cerebrovascular diseases, chronic obstructive pulmonary disease, and chronic multiple organ failure, the causes of death were analysed retrospectively. RESULTS: 94 cases (4.04%) were diagnosed as ARDS, but in the primary case record, only 27 cases (1.16%) had been diagnosed as ARDS/MOF. Of the 94 ARDS patients, 79 complicated by extrapulmonary organ damage involving the kidney, heart, liver, gastro-intestinal tract, and brain. A total of 305 organs were involved (average 3.24 organs each case). Lung failure only accounted for 15 cases. CONCLUSIONS: The combination of the diagnostic criteria of ARDS for high altitude area and flate area, injury severity scale, blood gas monitoring, and integrated traditional Chinese medicine and western medicine may improve the prognosis of ARDS.

Adolescent↗

PubMed1999

[Effects of environmental lead exposure in kindergartens on children's blood lead level].

OBJECTIVE: To determine if kindergartens' environmental status can influence children's lead exposure. METHODS: Environmental specimens, such as floor dust, peeled-off paint chip, soil and drinking water, as well as children's hand dust and blood samples, were collected and measured for their lead levels in 19 kindergartens, to analyze the relationship between children's blood lead levels and their environmental lead exposure. RESULTS: Geometric means of lead concentrations in indoor floor dust, peeled-off paint chip, dust fallout, outdoor floor dust, soil and drinking water were 86.5 microg/m(2), 235.5 microg/g, 445.9 microg/g, 172.4 microg/m(2), 70.1 microg/g and 12.5 microg/L, respectively. Lead level on children's hands averaged 3.4 microg at both hands. Blood lead levels in children correlated positively with the lead concentrations of outdoor floor dust and their hand dust, with correlation coefficients of 0.5186 and 0.2206, respectively. Multiple regression analysis showed that hand dust lead level in children entered the regression model with a largest standardized partial regression coefficient of 0.3842 and a coefficient of determination of 0.673 for the full equation with F = 6.52 and P < 0.01. CONCLUSION: Status of environmental health in kindergartens plays an important role in children's lead exposure. It is necessary to offer health education for children and make them wash their hands often and overcome unhealthy behavior of sucking their fingers.

Child Day Care Centers↗

PubMed1999

[Effects of lead exposure on their brain-stem auditory evoked potential in children].

OBJECTIVE: To determine if low lead exposure can influence auditory development in children. METHODS: Children were divided into two groups, i.e., low (< 0.483 micromol/L) and high (>or= 0.483 micromol/L) blood lead levels with atomic spectrophotometry (AAS). Latencies and latent intervals between peak waves of their brain-stem auditory evoked potentials (BAEP) in the two groups were measured and compared. RESULTS: There was positive correlation between blood lead levels and BAEP in wave III at right ear, wave V at both right and left ears and latent intervals between peak waves I to V, with correlation coefficients of 0.2991, 0.2748, 0.3248, 0.2064 and 0.2412, respectively. There was significant difference in latencies of wave III at right ear, wave V at both right and left ears and latent intervals between peak waves I to V at both right and left ears and those between waves of III to V at right ear in the low blood lead group. Latencies and latent intervals between peak waves were longer in the high blood level group (with a mean of 0.78 micromol/L and a range of 0.58 to 1.42 micromol/L) than those in the low one (with a mean of 0.30 micromol/L and a range of 0.17 to 0.45 micromol/L). CONCLUSION: Elevated blood lead level could cause prolongation of latencies and latent intervals between peak waves of BAEP and slowdown of the nerve conduction velocity, and so auditory development was influenced.

Child↗

PubMed1999

[Ultrastructural changes after space flight in Platycodon grandiflorum (Jacq.) DC].

OBJECTIVE: To substantiate the effect of space conditions on medicinal plants. METHOD: The seeds of platycodon grandiflorumg were set up in retrievable satellites. After returning to earth, the ultrastructural changes of leaves were studied. RESULT: Under light microscope, the leaf tissue structure of the flight group and the earth controlled group were alike and under electron microscope, some differences could be found in the nucleus and choloroplasts between the two groups. CONCLUSION: Space environment has some effect on Platycodon grandiflorum, and the effect needs to be further explored.

Cell Nucleus↗

PubMed1999

[Studies on the effects of space flight on Carthamus tinctorius L].

OBJECTIVE: To substantiate the effects of space condition of medicinal plants. METHODS: The seeds of Carthamus tinctorius were sent to space in retrievable satellites. After returning to earth, the seeds were stored at 0-4 degrees C, and cultured in the test field in the spring of next year. The peroxidases, soluble proteins and ultrastructure of leaves were studied in flowering stage. RESULTS: The peroxidase activity of the flight group was lower than that of the earth controlled group, and the protein content of the flight group was higher than that of the earth controlled group. The main bands in electrophoresis patterns of peroxidases and proteins were alike, and some bands were different. Some changes could be observed in the ultrastructure of chloroplast between the flight group and the earth controlled group. CONCLUSION: Space environments have some effect on Carthamus tinctorius. The results of this experiment are consistent with those of the previous experiment.

Carthamus tinctorius↗

PubMed1999

[Effect of space flight on ultrastructure in medicinal plant Datura innoxia Mill].

OBJECTIVE: To substantiate the effect of space environment on medicinal plants. METHOD: The seeds of Datura innoxia were set up in retrievable satellites. After returning to earth, the ultrastructural changes were observed by means of electron microscope. RESULTS: In cells of weightless group and hit group, some changes were found in chloroplast grana, starch grains and vesicles in chloroplasts. No obvious changes were observed in nuclei. CONCLUSION: Space environment has some effect on the ultrastructure in D. innoxia, and chloroplast is more sensitive to space environment than other organs.

Chloroplasts↗

PubMed1999

[Plasmid DNA expression in the muscle of rat tongue].

OBJECTIVE: To develop rat tongue model for plasmid DNA expression in vivo. METHODS: The expression vectors which contained either human-muscle specific promoter or SV40 promoter directing the transcription of reporter gene (E. coli LacZ gene) were used. The straited muscle of the tongue was used as a model system, and expression plasmid DNA was injected directly into Wistar rat tongue. PCR technique, X-gal histochemical staining and Southern blot hybridization were used to analyze reporter gene expression in vivo. RESULTS: The expression of reporter gene was correlated with the amount of injected DNA and the time of incubation in tongue muscle. beta-galactosidase activity can be detected 24 hours after injection of X-gal staining and even be detected after two months, but the maximal expression level was observed one week later. Coinjection of two expression plasmids resulted in co-expression in the same striated myofibers. E. coli LacZ DNA sequence was found in rat tongue injected with the plasmid DNA by PCR, which demonstrated capacity of the rat tongue myofibers uptaking foreign DNA. The Southern blot analysis showed the injected plasmid DNA existed outside the genome of rat muscle cells. No integration was detected. CONCLUSION: Direct plasmid DNA injection into tongue muscle was a simple and efficient approach to transfer foreign gene into striated muscle cells, and tongue was a good model for analyzing exogenous gene expression.

Animals↗

PubMed1999

[Cloning of DNA fragment related to salt tolerance in Sinorhizobium meliloti 042B].

Total DNA partially digested by EcoR I was prepared for S. meliloti 042B, in which 15-25 kb DNA fragments were collected. Vector pLAFR I was purified and digested by EcoR I, and then the various DNA fragments of 042B were ligated with pLAFR I by T4DNA ligase. Gene library of S. meliloti 042B was constructed with pLAFR I using E. coli S17-1 as recipient. The number of bacterial recombinants obtained was about 8,000 and 95% of them contained foreign DNA fragments. Using NTG, 042B was mutated on FY plates and 12 sensitive strains were screened at 0.5 mol/L NaCl from 2,000 colonies. One of them was named GZ17 and selected as a recipient strain. By biparental mating the foreign DNA fragments were introduced from gene library of strain 042B into recipient strain GZ17 which is sensitive to 0.5 mol/L NaCl. Then the transconjugants were grown on FY plates containing tetracycline (20 micrograms/mL) and 0.5 mol/L NaCl. A 7 kb inserted DNA fragment related to salt tolerance was obtained. In subcloning experiment, a 4 kb DNA fragment related to salt tolerance was obtained.

Cloning, Molecular↗

PubMed1999

[Effect of space flight on ultrastructure of chloroplast in Agastache rugosa].

OBJECTIVE: To substantiate the effects of space condition on medicinal plants, the seeds of Agastache rugosa were set up in retrievable satellites. METHODS: After returning to earth, the ultrastructural changes of chloroplasts were examined by means of electron microscope. RESULTS: Vesicles could be seen in the chloroplasts in the cells of earth controlled group, it was few and could not be found in the chloroplasts in the cells of weightless group and hit group. Some chloroplasts were degrading in the cells of weightless group, but this phenomenon was not observed in the cells of the other two groups. CONCLUSIONS: These results showed that space environment had some effect on the ultrastructure of chloroplasts in Agastache rugosa.

Agastache↗

PubMed1999

[GFAAS determination of trace lead in toothpaste using L'vov platform].

Sensitivity in determining low melting point metals is highly improved by means of platform technique in graphite furnace AAS. In this paper we describe a method of determining trace lead in toothpaste by this technique. The method of making the platform and the selection of the platform coating were discussed and the results with and without the platform were compared. The optimum ashing temperature, atomization temperature and experimental conditions were investigated. The interference of large amount Al and Ca in the matrix on determination of trace lead can be minimized by using platform technique. The precision of about 0.9% and detection limit of about 15 ng obtained by this improved method are much better than those by methods without platform.

Graphite↗