Biomedical subjects

Y Song

Publications and source records attributed to Y Song.

At least 109 records · Page 6Linked to original sources

PubMed2001

[Co-metabolic degradation of pyrene in soil].

High molecular weight Polycyclic Aromatic Hydrocarbons (PAHs) are always degraded by means of co-metabolism. This study compared the degradation process of pyrene as sole source of carbon and energy and co-metabolic degradation process of pyrene. The degradation rate of pyrene after 25 days in the first process was 57%, while the degradation rate of pyrene in the co-metabolic processes were about 80%. The half-life of pyrene in the co-metabolic process was shorter than those in the processes without co-metabolism. Salicylic acid, phthalic acid, sodium succinate could serve as co-metabolic substrate to enhance the degradation rate of pyrene, and sodium succinate has the best effect. There was co-metabolic relationship between pyrene and phenanthrene which was a kind of low molecular weight PAHs, phenanthrene accelerated the degradation of pyrene, while naphthalene didn't. The principle of the co-metabolism and the optimal material used as co-metabolic substrate were demonstrated in this paper.

Environmental Pollution↗

PubMed2001

[Study on the exercise test in young health men].

OBJECTIVE: To define the reaction of the respiration and circulation; and to find methods to quantitatively evaluation dyspnea and evaluate the methods that determine anaerobic threshold(AT) with the healthy man during exercise. METHODS: Exercise test was used for 43 healthy young man to measure the index of gas metabolism and artery potassium. The relation between the index of Borg scale (BS) and the oxygen uptake per minute (VO2) was observed. The methods of how to obtain anaerobic threshold(AT) were evaluated by the five kinds of gas metabolism. RESULTS: (1) VD/VT were significantly decreased from the rest to the maximal load exercise (0.28 +/- 0.55 vs 0.19 +/- 0.55, P < 0.01). (2) Seran potassium is state of after exercise (3.76 mmol/Lvs +/- 0.29 mmol/Lvs 4.10 mmol/L +/- 0.38 mmol/L, P < 0.01). (3) BS were closely correlated with VO2 during exercise, From the linear regression line 3 variables Borg scale slop(BSS), Threshold load of dyspnea(TLD), and breakpoint load of dyspnea (BLD), could be derived for quantitative evaluation of dyspnea. (4) ATVCO2 were1208 ml/min +/- 233 ml/min, and it were consistent with ATVE and ATVEO2 (P > 0.05). CONCLUSION: The artery potassium is increased after exercise in young health men. The methods of quantrta-tive evaluation of dyspnea can be used during exercise. It is suitable for AT to obtained by the sharp turning point of the carbon dioxide production (VCO2), minute ventilation (VE) and Ventilation equivalent oxygen (VEO2).

Adult↗

PubMed2001

[Changes of pulmonary function and partial oxygen pressure before and after bronchoalveolar lavage in patients with interstitial lung diseases].

OBJECTIVE: To study the influence of bronchoalveolar lavage(BAL) on pulmonary physiological function and partial oxygen pressure(PaO2). METHODS: Pulmonary function and partial oxygen pressure were measured in 42 patients with interstitial lung disease (ILD) before and after BAL, 7 non-smoker volunteers as control group. RESULTS: VC% and FEV1% decreased significantly from (74 +/- 17)% to (64 +/- 19)% and from (72 +/- 9)% to (65 +/- 12)%, respectively. PaO2 decreased from(77 +/- 11) mm Hg to (63 +/- 11) mm Hg. The above parameters were also decreased in control group, but had no statistical significance. CONCLUSION: Pulmonary physiological function and partial oxygen pressure of patients with ILD are influenced by BAL process.

Adult↗

PubMed2001

Surgical treatment of 52 patients with congenital coronary artery fistulas.

OBJECTIVE: To evaluate the outcome of surgical treatment for congenital coronary artery fistulas (CAF) in 52 patients seen between May 1988 and July 1999. METHODS: Fifty-two patients ranging in age from 9 months 58 years (mean 15.7 +/- 16.4 years) were studied. Thirty-six patients had no other cardiac defects, 9 of those patients were more than 20 years old and presented with symptoms. Only one of 36 patients less than 20 years old had clinical findings before surgery. Sixteen patients had associated cardiac lesions. The site of fistula origin was the right coronary artery in 37 patients (71.2%), and the left coronary artery in 15 patients (28.8%). The sites of CAF drainage were the right ventricle, right atrium, left ventricle, left atrium and pulmonary artery in 22 (42.3%), 16 (30.8%), 6 (11.5%), 3 (5.8%), and 5 (9.6%) patients, respectively. The mean diameter of the fistula in 43 patients with single ostium was 7.34 +/- 4.12 mm. RESULTS: Cardiopulmonary bypass was used in all patients and no patient died. An arteriotomy was made on the anomalous coronary artery and the proximal opening of a fistula was closed within the vessel in 10 patients. Closure of the distal opening of a fistula draining into a cardiac chamber or pulmonary artery was performed in 26 patients. In 16 patients, both the proximal and distal opening were closed. Two and 3 distal opening of a fistula were found in 6 and 3 patients, respectively. No residual shunt was found before patients were discharged from the hospital. Forty patients were followed up for a mean period of 3.14 +/- 1.84 years. The remaining 12 patients could not be contacted during follow-up. No clinical symptoms were found in those patients during follow-up but one patient still presented with ST-T change. CONCLUSION: Early and properly surgical management is safe and effective for congenital coronary fistula.

Adolescent↗

PubMed2001

Detection of human herpesvirus 8 DNA in acute leukemia patients.

OBJECTIVE: To determine the prevalence of human herpesvirus 8 (HHV-8) DNA in acute leukemia (AL) patients. METHODS: The presence of HHV-8 DNA sequences in peripheral blood mononuclear cells (PBMC) and bone marrow mononuclear cells (BMMC) from 50 AL patients was examined using polymerase chain reaction (PCR). Nine human hematopoietic cell lines and PBMC from 30 normal donors were also included. RESULTS: HHV-8 DNA sequences were detected in one case of acute myelogenous leukemia (AML). The specimens from the bone marrow aspirate, peripheral blood and serum of this patient were all positive. None of the normal donors and human hematopoietic cell lines showed evidence of HHV-8 DNA. CONCLUSION: The results suggest that the prevalence of HHV-8 is low in AL in China.

Acute Disease↗

PubMed2001

[mRNA expression and mutation of MTA1 and nm23H1 genes in ovarian carcinoma in relation to lymph node metastasis].

OBJECTIVE: To investigate mRNA expression and mutation of MTA1 and nm23H1 genes in ovarian carcinoma (OC) in relation to lymph node (LN) metastasis. METHODS: A panel of eight normal ovarian tissues, twenty primary OC specimens and twenty corresponding LNs was examined for mRNA expression and mutation of MTA1 and nm23H1 genes by using RT-PCR and RT-PCR-SSCP. The level of expression was determined by the relative optic density (ROD) of the PCR products. RESULTS: The frequency of MTA1 overexpression was 100% (7/7) in primary OC with metastasis but only 38.5% (5/13) in those without metastasis (P = 0.0103). Overexpression of MTA1 was observed in 87.5% (6/7) of LNs with metastasis but in only 23% (3/13) of LNs without metastasis (P = 0.0118). In contrast with MTA1, low expression of nm23H1 mRNA was seen in 7 of 7 OC with metastasis but only in 4 of 13 (30%) of those without metastasis (P = 0.0043). Low nm23H1 expression was also seen in 7 of 7 LNs with metastasis but only in 5 of 13 (38.5%) nonmetastatic LNs (P = 0.0102). The ROD ratio of MTA1 to nm23H1 increased with the development of metastasis. No mutation of MTA1 and nm23H1 was found by SSCP analysis. CONCLUSION: The mRNA expression of MTA1 and nm23H1 is positively and negatively correlated with LN metastasis, respectively. Expression abnormalities but not mutation of the two genes are frequent events related to LN metastasis of ovarian cancer.

Down-Regulation↗

PubMed2001

[Video colposcopy in diagnosis of cervical squamous intraepithelial lesions].

OBJECTIVE: To study the accuracy and efficiency of video colposcopy in diagnosis of cervical squamous intraepithelial lesions and clinical significance of seven colposcopic signs. METHODS: Two hundred and seventy-five patients with an abnormal cervical smear or vulva condyloma acuminata were re-evaluated by video colposcopy. 265 cervical biopsies performed under the guidance of video colposcopy for pathological study, as well 8 endocervical curettage (ECC) and 237 loop electrosurgical excision procedure (LEEP). RESULTS: The sensitivity, specificity and positive rate of video colposcopy in evaluation of cervical squamous intraepithelial lesions were 95.9%, 77.7%, and 84.5%. Video colposcopy diagnostic accuracy was 93.8% tally with the pathological results in observing normal transformation zone. False negative rate was 6.1%. 76.2% of cases with subclinical papillomavirus infection by acetowhite epithelium, while false negative rate was 23.7%. Twin signs, triple signs and cervical carcinoma were 100.0% tallying with the diagnosis of cervical lesions. CONCLUSIONS: Video colposcopy can be a very accurate diagnostic method in clinical practice. It is quite sensitive in diagnosis of severe cervical lesions. However, there was a relative high false negative rate in diagnosing mild cervical lesions.

Colposcopy↗

PubMed2001

[Experimental study for lung fluid transport by epithelial cells and aquaporins].

OBJECTIVE: To explore the effects of aquaporins (AQP) 1, 4 on water transport between airspace and pulmonary capillary and high pressure pulmonary edema. The other purpose was to study the active alveolar fluid transport as well as alveolar fluid clearance (AFC) in different pH of airspace. METHODS: The effects of AQP1, 4 on water transport between airspace and pulmonary capillary and high pressure pulmonary edema were studied by surface fluorescence methods and gravimetric method respectively, AFC and AFC in airspace with different pH were measured by isotope method. RESULTS: AQP1 knockout inhibited water transport through pulmonary capillary and also reduced high pressure pulmonary edema. Salbutamol increased AFC, but it was reduced when propranolol was used together. AFC was improved by terbutaline, isoproterenol, salmeterol when pH > 2.5 in airspace, but the effect was reduced after pH < 2.5 in airspace. Sodium channel inhibitor, Benzamil, could also inhibit AFC. CONCLUSIONS: AQP1 knockout significantly reduced water transport through alveolar capillary, and also reduced high pulmonary edema slightly. beta adrenergic stimulant improved AFC in mechanically ventilated rats. Intact airspace is very important for the function of AFC, however, the effect of AFC was impaired after lung injury induced by pH < 2.5 in airspace.

Animals↗

PubMed2001

[A study on pathological changes and the potential role of growth factors in the airway wall remodeling of COPD rat models].

OBJECTIVE: To study the pathological features of the smooth muscles and collagen in small airways of the COPD rat models and their roles in the airway obstruction, to evaluate the relationship between TGF-beta(1), EGF and bFGF and the airway wall remodeling. METHOD: Rat COPD model (model group) was established by intratracheal instillation of lipopolysaccharide (LPS 200 microgram/200 microL) twice and exposure to cigarette smoke daily. Drug intervention groups received either daily inhalation of budesonide, ipratropine or heparin respectively, starting on the 8 th day or TGF-beta(1) monoclonal antibody (TB21) 0.5 mg twice (6 th and 19 th day) via the tail veinous injection. At the end of four weeks, the thickness of the smooth muscles and collagen in bronchi and pulmonary arteriole wall were measured by means of image analyzer (CMIAS). Expression and localization of the 3 growth factors were observed in trachea, bronchi and lung tissues by immunohistochemistry and in situ hybridization. The levels of PC III, Ln and HA in the serum and BALF were determined by the RIA method. RESULTS: Significant thickening of the smooth muscles and collagen were found in the bronchi and pulmonary arterioles of the model group in comparison with those of the control group. There was significant decrease in the thickness of the collagen and smooth muscles in the small airways in TB21 group and heparin group. Statistically negative relationships were shown between the thickness of either smooth muscles or collagen in the small airways and FEV(0.3) (all P < 0.05). The levels of PC III, Ln and HA in COPD rat models were higher than those of control groups to varying extent. Expressions of TGF-beta(1), EGF and bFGF in the epithelial cells of bronchi, endothelial cells of pulmonary arterioles and in the macrophages of the model group were significantly higher than those of control group. The above mentioned parameters were reduced in different extent in drug intervention groups, in particular, the smooth muscles thickness in heparin group and the collagen thickness in TB21 group were significantly decreased compared to the model group. CONCLUSION: Thickening of smooth muscles and collagen in the bronchi constitutes the fundamental pathology of airway remodeling in the rat COPD model. The excessive depositions of ECM are important characteristics of COPD. TGF-beta(1), EGF and bFGF may play an important role in the airway wall as well as pulmonary arteriole remodeling. The intervention against TGF-beta(1) and long term inhalation of heparin may be of use in the inhibition of airway remodeling in COPD.

Animals↗

PubMed2001

[Study on the pitting corrosion-resistant of Ti-75 alloys with different from oxidize temperatures in vacuum in oral cavity].

OBJECTIVE: To study the property of pitting corrosion-resistant of Ti-75 alloys with different from oxidize temperatures in vacuum in oral. METHODS: Ti-75 alloys were prepared 30 mm x 10 mm x 1 mm specimens and annealed at 200 degrees C, 300 degrees C, 400 degrees C, 500 degrees C oxidize temperatures in vacuum. The open-circuit potential (Ecoor) and the breakdown potential (Eb) were measured, and the cyclic anodic polarization curves was drawn. RESULTS: The Ecoor of Ti-75 alloys annealed at 200 degrees C oxidize temperatures in vacuum is -49.0 mV. At 300 degrees C, 400 degrees C, 500 degrees C oxidize temperatures in vacuum, the different Ecoor is -75.3 mV, -51.3 mV and -60 mV respectively. The Eb of Ti-75 alloys annealed at 200 degrees C oxidize temperature for 5 minutes in vacuum is the highest (+180 mV). CONCLUSION: It is better for Ti-75 alloys being annealed at 200 degrees C for 5 minutes in vacuum to release the stress of machine duplication and to resistant pitting corrosion.

Alloys↗

PubMed2001

[Bioremediation of mineral oil and polycyclic aromatic hydrocarbons (PAHs) in soils with two plant species].

With alfalfa (Medicago sativa) and paddy rice as test plants, and with pollutant level, specific bacteria, fungi and organic fertilizer as control factors, the bioremediation of mineral oil and polycyclic aromatic hydrocarbons (PAHs) in soils with two plant species was conducted. The results showed that the degradation rate of mineral oil was promoted by fertilization in alfalfa soil, but not in paddy rice soil. The degradation rate of total PAHs (11 PAH listed in USEPA) was increased by fertilization both in alfalfa and in paddy rice soil, and the promotion effect of fertilizer was better in paddy rice soil than in alfalfa soil. The fertilization rate was positively related to the rhizospheric indigenous fungi and bacteria's CFU in alfalfa soil, but only to the indigenous bacteria's CFU in paddy rice soil. The fungi and bacteria's CFU in both test soils had no positive relation with the amount of specific bacteria and fungi spiked. The degradation rate of 3-ring PAHs was enhanced in both alfalfa and paddy rice soil by fertilization, and the effect was stronger in paddy rice soil than in alfalfa soil. However, fertilization had no positive effect on the degradation of 4-ring PAHs.

Bacteria↗

PubMed2001

[Morphological observation of Mahaim's fibers in 7 cases].

OBJECTIVE: To investigate the Mahaim's fibers of the cardiac conduction system (CCS) of human hearts and study their morphological features. METHODS: The CCS from 165 cases of sudden death without extracardiac causes and those from 760 cases of non-cardiac death were sampled using a method established by the authors. Serial sections were prepared for histological observation. RESULTS: Mahaim's fibers were discovered in 7 cases, 5 cases were in the sudden death group, accounting for 3% in that group, 2 cases were in the non-cardiac death group, accounting for 0.26% in that group. All cases belonged to the bundle-ventricular branch type. The characteristics of Mahaim's fibers were found to be as follows. Their transverse diameter was 10 - 35 microns. The bodies of the Mahaim's fibers that originated from A-V bundle were slender with nucleus in the middle of the cell. While the shape of cells from the left bundle branch varied according to the origin of the Mahaim's fiber with size enlarging from up downward. Both types of cells showed abundant lightly stained cytoplasm, similar to A-V bundle and left bundle branch cells. The cells were not bifurcated and some of them were surrounded by a thin layer of fibrous tissue. CONCLUSION: Mahaim's fibers are not a rarity and it is an abnormal development of an A-V by-path.

Adolescent↗

PubMed2001

[The correlation of multidrug resistance phenotype with clinical response to chemotherapy in laryngeal cancer].

OBJECTIVE: The correlation of multidrug resistance(MDR) phenotype with clinical response to chemotherapy was investigated in patients with laryngeal cancer. METHOD: Tumor specimens prior to neoadjuvant chemotherapy from 36 cases of laryngeal cancer were collected for detection of P-glycoprotein (P-gp) with anti-Pgp monoclonal antibodies (JSB-I). Immunohistochemical assays were used for P-gp detection on 5 microns thick frozen section. Anti-Pgp monoclonal antibodies(JSB-I) as primary antibodies and goat anti-mouse IgG monoclonal antibodies as second antibodies were applied. All patients received preoperative induction chemotherapy with a regimen of cisplatin, 5-fluorouracil and pingyangmycin. Evaluation for tumor response was scored as follows: Response to chemotherapy was graded as good for complete response or partial response; as poor for stable disease or progressive disease. RESULT: Of the 36 pretreatment specimens, 12(33.3%) were P-gp positive and 24 (66.7%) were P-gp negative. Among the 12 patients with P-gp positive, 3(25%) had a good response and 9(75%) had a poor response. Of the 24 patients with P-gp negative, 21(87.5%) had a good response and 3(12.5%) had a poor response (P < 0.05). CONCLUSION: These preliminary data suggest that a significant correlation between MDR phenotype, Pgp-mediated and chemotherapy resistance existed.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2001

[Effect of gene disruption of aveD on avermectins production in Streptomyces avermitilis].

Recombinant plasmid pCZ2(pKC1139::475 bp aveD) was used for aveD gene disruption in Streptomyces avermitilis 76-9. The plasmid was inserted into the chromosome by homogenous recombination between partial aveD gene in the plasmid and aveD in the chromosome. Disruptants were confirmed by Southern blotting. Shaking flask experiments and HPLC analysis showed that the disruptant produced only four components, which were C5-oxo-avermectin B1a, B1b, B2a, B2b as identified by UV, IR, NMR, and MS. This revealed that both aveD and aveF were not expressed in the disruptant. This is consistent with that aveD and aveF are in a transcription unit. This paper also provided a new genetic method to obtain C5-oxo-avermectin B-producing strain.

Bacterial Proteins↗

PubMed2001

[Analysis of the plasma radiation induced by laser ablating Al at low pressure].

The plasma was obtained with Nd:YAG laser ablating aluminum. The energy of a pulsed laser beam was set up to 145 mJ. Ar gas was used as protecting gas, its pressure was set up to 100 Pa. The information of the plasma radiation was acquired with time-resolved technique. The time-resolved spectra including continuum radiation, absorption of continuum radiation and Al atomic spectral lines radiation were obtained. The evolutions of all these radiations were analyzed, and the relationship between them was discussed briefly. We found that the evolutions of all these radiation at the low pressure were similar to that of at the pressure of one atmosphere.

English Abstract↗

PubMed2001

[Determination of Fe, Al, Ca, Ti, P and Cu in silicon metal by XRF].

This article puts forward a sample preparation method that first dissolve the sample by acid and evaporate the solution then melt the remains by flux. This method resolves the problem that silicon metal can't easy to prepare sample by fusion, and it can determine several elements in the sample simultaneously. This method overcomes the limit of standard sample and removes the matrix effects. The range of determination is wide and the results is accurate. The condition of preparing sample was confirmed by test.

Aluminum↗

PubMed2000

Study on the fluorescence spectra and electrochemical behavior of ZnL2 and Morin with DNA.

The interactions of Morin (2', 3, 4', 5, 7-pentahydroxyflavone) and its Zn-complex, ZnL2.3H2O [L = Morin (2'-OH group deprotonated)], with calf thymus DNA have been studied using fluorimetric and electrochemical methods. ZnL2.3H2O has different spectral characteristics and electrochemical behavior from that of Morin in the presence of DNA. Increasing fluorescence is seen for ZnL2.3H2O with DNA addition whereas decreased fluorescence is observed for Morin. An isosbestic point appears at 560 nm for the DNA-ZnL2.3H2O system with ethidium bromide (EB) addition while no isosbestic point is detectable for Morin. Quenching fluorescence is observed for DNA-EB system when ZnL2.3H2O is added whereas no quenched fluorescence is seen for DNA-EB system with Morin addition. The above results suggest that Morin and ZnL2.3H2O can both bind to DNA, but the binding mode is different. The complex binds to DNA mainly by intercalation, while Morin binds in a non-intercalating mode. The binding constant and binding site sizes are derived from electrochemical methods. For ZnL2.3H2O, the binding constant is 5.0 x 10(4) l mol(-1) at 20 degrees C, and the binding site size n(s) is 5.

DNA↗

PubMed2000

Overexpression of wild-type RhoA produces growth arrest by disrupting actin cytoskeleton and microtubules.

We have investigated the role of Rho GTPase in cell growth by generating stable cells that express the wild-type RhoA (RhoA(wt)) under the control of an inducible promoter. Induction of RhoA(wt) had a biphasic effect on the actin cytoskeleton. At low levels of expression, RhoA(wt) stimulated the assembly of actin stress fibers without affecting cell growth. At high levels, there was a paradoxical disruption of the actin cytoskeleton accompanied by a growth arrest. Cell cycle analysis revealed a dual block at the G(1)/S and G(2)/M checkpoints. The G(1)/S arrest correlated with the accumulation of p21(Cip1), resulting in the inhibition of cdk2 activity, whereas the G(2)/M block correlated with the loss of microtubules. The cyclin B level and the cdc2 kinase activity, however, were increased, suggesting that the progression through mitosis rather than entry into the G(2)/M is defective when RhoA(wt) is overexpressed. Similar cell cycle defects and the loss of microtubules were observed after a cytochalasin D treatment, indicating that the ability of RhoA to regulate the integrity of actin cytoskeleton may be critical for the cell cycle transition through both the G(1)/S and M phase checkpoints.

Actins↗