Biomedical subjects

Xueyuan Zhang

Publications and source records attributed to Xueyuan Zhang.

6 recordsLinked to original sources

PubMed2006

[An in vitro investigation of the regulation mechanism to the blood-labyrinth barrier permeability of guinea pig inner ear].

OBJECTIVE: To investigate the regulation mechanism of the blood-labyrinth barrier permeability of guinea pig inner ear. METHOD: The cultured endothelial cell was derived from the stria vascularis from guinea pig inner ear. We exposed guinea pig inner ear capillary endothelial cell monolayers to substances known to increase or decrease cyclic AMP and measured their effect on endothelial permeability to albumin and Evan's blue and endothelial cell cyclic AMP and F-actin concentrations. RESULT: Cholera toxin (CT) led to a remarkable increase in cyclic AMP concentration and a marked reduction in F-actin concentration which was associated with remarkable reduction in albumin and Evan's blue transfer across endothelial monolayers; In contrast, katlex led to an obvious reduction in cyclic AMP concentration and a marked increase in F-actin concentration which was associated with obvious increase in albumin and Evan's blue transfer across endothelial monolayers. CONCLUSION: The results indicated that cyclic AMP is an important determinant of the blood-labyrinth barrier in vitro. The barrier function changes are probably associated with apparent endothelial shape changes and qualitative and quantitative changes in F-actin.

Actins↗

PubMed2005

[Effect of adriamycin on expression of mdr1 gene in guinea pig cochlea lateral wall].

OBJECTIVE: To study whether ADM affect the expression of mdr1 gene in guinea pig cochlea lateral wall. METHOD: Sixty white guinea pigs with red eyes were divided into three groups: control group, NS group and ADM group. Guinea pigs were administered an intravenous injection of 30 mg/kg ADM. Four hoars later,ten animals were then immediately sacrificed, and the bony labyrinths were removed. The remaining ten animals were sacrificed after 24 h. The effect of ADM, an ototoxicity drug, on expression of mdrl gene in guinea pigs cochlea lateral walls were observed with RT-PCR. Furthermore, the ADM concentration in endolymph were measured by high performance liquid chromatography. RESULT: For ADM group, the density ratio of mdr1 to beta-action of the 24 h was significantly greater compared to that of the 4 h or controls; In contrast, the ADM concentration of 4 h was significantly higher than that of the 24 h. CONCLUSION: mdr1 gene in normal guinea pig cochlea lateral wall is a stress gene. It can be induced by ADM; it may be not only related to reduce the accumulation of ototoxicity drug in endolymph, but also associated with the protective function of inner ear.

Animals↗

PubMed2005

[Microecosystem of ostiomeatal complex and its changes via functional endoscopic sinus surgery].

OBJECTIVE: To study the composition of microecosystem in ostiomeatal complex on adults and its changes via functional endoscopic sinus surgery. METHOD: Two hundred adults were grouped based on pre- or postoperation as well as its type of sinusitis. Swab speciemens were taken from three different sites of ostiomeatal complex in each individual, cultivations and identifications of aerobes, anaerobes and fungi were performed simultaneously; the microecosystem of OMC was analysesed. RESULT: All aerobes belonged to thirteen genera thirty species, anaerobes were three species and three major species of fungus were cultured, most of them have none or less virulence; statistically, none significance were shown between differences of type I and II (P > 0.05); as to aerobes, difference between preoperative group and control group had significance (P < 0.01); culture rate descended postoperatively while the difference had no significance compared to preoperative group (P > 0.05); difference of rate of same aerobic culture from three sites (RSAC) between preoperative and control group was significant (P < 0.01), while wasn't between postoperative group and control one (P > 0.05). Taking fungi into account, differences among all groups had no significance (P > 0.05); anaerobes were rare in all groups. CONCLUSION: Being a microecosystem under normal condition, ostiomeatal complex is relatively clean and exists as a whole space; while chronic inflammation separate different parts of which from each other with multimicrobial existence; FESS reverses the separation of the microecosystem in OMC and rebuild it as a whole again, thus promote the recovery.

Adolescent↗

PubMed2005

[Expression of ECP during different phrase of transitionary process of mucosa in sinus cavity after endoscopic sinus surgery].

OBJECTIVE: To study the secretion of ECP during different phrase of transitionary process of mucosa in sinus cavity after endoscopic sinus surgery. METHOD: Secretion of ECP was determined with enzyme-fluoroimmunoassay method during different phrase of transitionary process of mucosa in sinus cavity in 20 patients with type I and type II chronic sinusitis after endoscopic sinus surgery. RESULT: Comparing the patients in 1-2 week after surgery with the conditions before surgery,a significant decrease of secretion of ECP was found (P < 0.01). In 4-6 weeks after surgery, increasing amounts of secretion of ECP were found, nearly reaching the conditions before surgery again. In 10-12 weeks, the secretion of ECP tended to the level as 1-2 week after surgery. CONCLUSION: This study may indicate that the ECP involves in the transitionary process of mucosa in sinus cavity after endoscopic sinus surgery.

Chronic Disease↗

PubMed2004

Predictive models of copper runoff from external structures.

A general model for annual runoff rate predictions of total copper from naturally patinated copper on buildings at specific urban or rural sites of low chloride influence has been deduced from laboratory and field data. All parameters within the model have a physical meaning and include the average annual rain acidity (pH), the annual rain quantity and the geometry of a building in terms of surface inclination. In 70% of all reported annual runoff rates, the predicted values are within 30% from the observed values. The individual and interactive effect of rain composition in terms of pH, sulfate, chloride and nitrate concentration was investigated in immersion experiments in artificial rain water representative of urban and rural sites of Europe. The results show pH to have a dominating effect on patina dissolution, nitrate to have a small inhibiting effect, whereas no significant effect was seen for chloride and sulfate. In case pH data are not available, a model has been statistically deduced from field data by considering SO2 as influencing parameter, rather than pH. The predictability with the SO2 model is not as good as with the pH model i.e. the pH model should preferentially be used since it is a better predictor and all parameters within the model can be physically explained.

Chlorides↗

PubMed2002

[Transendothelium electric resistance and permeability on bovine serum album of cochlear microvascular endothelial cells from guinea pig].

OBJECTIVE: To study the dynamic changes and the peak phases of transendothelial electric resistance (TEER) during the growth of cochlear microvascular endothelial cells (CMEC) in guinea pigs and the monolayer endothelial cells permeability on radioiodinated 125I bovine serum album (RISA). METHOD: 1. Establish a model in vitro for the permeability of CMEC using small pool technique. 2. Research the model's TEER and its permeability on RISA. RESULT: 1. The TEER changed dynamically and reached the peak about seven days after inoculation of culture cells at 5 x 10(4)/cm2 level during the CMEC proliferated. The peak values of TEER was 118.9 +/- 18.5 omega/cm2; 2. After RISA administration, the Bake-time curve took on an ascending parabola, while within 90 min appeared like a straight line. CONCLUSION: The TEER and the Varity curve on RISA reveals the permeability of CMEC in vitro.

Animals↗