1.Fine Mapping of a Deafness Mutation hml on Mouse Chromosome 10.
Qing Yin ZHENG ; Belinda S HARRIS ; Patricia F WARD-BAILEY ; Heping YU ; Roderick T BRONSON ; Muriel T DAVISSON ; Kenneth R JOHNSON
Academic Journal of Xi'an Jiaotong University 2004;25(3):209-212
OBJECTIVE: to map a mouse deafness gene, identify the underlying mutation and develop a mouse model for human deafness. METHODS: genetic linkage cross and genome scan were used to map a novel mutation named hypoplasia of the membranous labyrinth (hml), which causes hearing loss in mutant mice. RESULTS: 1. hml was mapped on mouse Chr 10 (~43 cM from the centromere) suggests that the homologous human gene is on 12q22-q24, which was defined on the basis of known mouse-human homologies (OMIM, 2004). 2. This study has generated 25 polymorphic microsatellite markers, placed 3 known human genes in the correct order in a high-resolution mouse map and narrowed the hml candidate gene region to a 500kb area.
2. Study on chromatographic fingerprint of sarcandra glabra (Thunb.) by microwave-assisted extraction coupled to HPLC/DAD
Academic Journal of Xi'an Jiaotong University 2010;22(4):211-217
Microwave-assisted extraction (MAE) was used for extraction of effective components of sarcandra glabra (Thunb.), and then chromatographic fingerprint of sarcandra glabra (Thunb.) was studied by high performance liquid chromatography/diode array detector (HPLC/DAD). The conditions of MAE were optimized by an orthogonal experiment, and then the authentication and validation of the chromatographic fingerprint were conducted. Nine peaks were identified as common peaks in the fingerprint chromatograms, and isofraxidin was considered as a reference compound and quantified. Relative standard deviations of retention time and peak area of each component were less than 3 % and 8 %, respectively. Similarity and difference analysis were conducted by use of PCA and relation coefficient. Twenty batches of sarcandra glabra (Thunb.) samples from two different producing areas could be classified into two different groups in the PCA model. The results showed that MAE-HPLC/DAD method was simple, efficient and stable for the study of complex chromatographic fingerprint of sarcandra glabra (Thunb.), which could provide more reliable and precise information for quality evaluation.
3. Analysis of ganciclovir and its related substances using high performance liquid chromatography and liquid chromatography-mass spectrometry methods
Academic Journal of Xi'an Jiaotong University 2010;22(4):218-222
Objective: High performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC/MS) methods were developed for the determination of ganciclovir and its related substances. Methods: A Hypersil ODS2 column (4.6 mm x 250 mm, 5 μm) was used with a mobile phase of 0.02 M potassium dihydrogen phosphate buffer (pH 6.0)-methanol (92:8) at a flow rate of 1.0 mL/min, and UV detector set at 254 nm was used for monitoring the eluents. Results: The method was simple, rapid, selective and capable of separating all related substances at trace level with a detection limit of 0.04 μg/mL. It has been validated with respect to accuracy, precision, linearity, and limits of detection and quantification. The linearity range was 10.2-153.0 μg/mL with r = 0.9998. The percentage recoveries ranged from 96.7% to 101.6%, and RSD was 1.24%-1.96% (n = 5). Conclusion: The method was found to be suitable not only for monitoring the reactions during the process development but also for quality control of ganciclovir. For identification of related substances, LC/MS was used. The mainly related substances of ganciclovir active pharmaceutical ingredients (API) were determined as guanine, (1, 3-dioxolan-4-yl) methyl acetate, and diacetyl guanine.
4. In situ absorption and metabolism of stilbene glycoside in rat
Academic Journal of Xi'an Jiaotong University 2010;22(4):223-232
Stilbene glycoside (TSG) has been shown to have many beneficial properties. It is therefore essential to understand the absorption and metabolism of TSG in detail. We determined the recovery of TSG and its metabolites (TSG sulfate/glucuronides) in rat gastric contents, gastric mucosa, portal vein plasma, celiac arterial plasma, bile, and urine after administration of 15 mg of TSG in 0.5 mL physiological saline or incubation for 20 min in situ in the stomach of rats. Within 20 min, (64.0±9.8)% of the administered TSG disappeared from the stomach) later, TSG was recovered in both free and conjugated forms in plasma and bile, but not in urine. On the other hand, only free TSG was detected in the gastric contents and mucosa; it was also detected in the portal vein plasma as (48.1±3.5)% of the total TSG (all forms of TSG). However, the proportion of free TSG in the celiac arterial plasma and bile decreased to 4%-10%. In addition, the proportion of free TSG to total TSG in the liver microsome incubation mixture after TSG was incubated in liver microsome at 37°C for 30 min was very low [(10.6 ± 2.6)%]. These results indicate that TSG could be quickly absorbed from the rat stomach, conjugated in liver and excreted in bile. Such novel information would be helpful for the use of TSG as a beneficial natural product which may improve its proposed efficacy in preventing chronic diseases.
5. Effect of acidity of drugs on the prediction of human oral absorption by biopartitioning micellar chromatography
Academic Journal of Xi'an Jiaotong University 2010;22(4):233-240
Biopartitioning micellar chromatography (BMC) is a potentially high throughput and low cost alternative for in vitro prediction of drug absorption, which can mimic the drug partitioning process in biological systems. In this paper, a data set of 56 compounds representing acidic, basic, neutral and amphoteric drugs from various structure classes with human oral absorption (HOA) data available were employed to show the effect of acidity of drugs in oral absorption prediction. HOA was reciprocally correlated to the negative value of the capacity factor (kBMC) determined by BMC at pH 7.4 and 6.5. The relationships between kBMC and the corresponding HOA values of all compounds were rather poor, but the correlations were improved when the acidity of drugs was taken into consideration. Moreover, the proposed models allowed obtaining of good predictive values for both highly and poorly absorbed compounds. It is demonstrated that the constructed models derived from compounds with the same kind of charge property are of more practically meaningful and rigorous.
6. Preliminary study on Salvia miltiorrhiza bung endophytic fungus
Academic Journal of Xi'an Jiaotong University 2010;22(4):241-246
Objective: To select the strains which can produce tanshinone II A like its host plant Salvia miltiorrhiza bung. Methods: A total of 50 strains of endophytic fungi were isolated from healthy, living and symptomless tissues of Salvia miltiorrhiza bung, among which 29 strains were obtained from the root, 14 from the stem, 3 from the leaf, 3 from the flower and 1 from the seed. Their antimicrobial activities against nine different bacteria, including both Gram-negative and Gram-positive bacteria, were measured by Oxford plate agar diffusion bioassay. Results: Our data showed that all but four strains had significant antibacterial activities on at least one indicator bacterium to some extent, and five strains (DR1, DR4, DR16, DR18 and DF2) manifested quite prominent antibacterial activities against certain pathogenic bacteria. In some degree, it might indicate that this endophytic fungus isolated from the tissues of Salvia miltiorrhiza bung has a potential value as a natural antibacterial medicine as well. Thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC) were carried out to test selected strains, both inside and outside of the cell to see if any strain can produce tanshinone II A. The result showed that extracts from three strains, labeled as DR12 (outside cell), DR21 (inside cell) and DF3 (inside cell), had a component with the same Rf value in TLC assay as that of authentic tanshinone II A. The extract from DR12 (outside cell) and DR21 (inside cell) had a peak at retention time identical to that of authentic tanshinone II A in HPLC. Conclusion: The fungi appear to produce the bioactive compound tanshinone II A, and they could be used to produce tanshinone II A by fermentation. It provides a new way to synthesize this natural medicine.
7. Antibiotic prescribing patterns for upper respiratory tract infections in rural Western China
Academic Journal of Xi'an Jiaotong University 2010;22(4):247-251
Objective: To explore the prescribing patterns of outpatients receiving antibiotics for upper respiratory tract infections (URTIs) in rural Western China and to identify the correlation in terms of doctors and patients characteristics. Methods: Totally 7 678 prescriptions for URTIs were collected from 680 primary health village clinics of 40 counties across 10 provinces of Western China. Two outcome variables were used in the analysis: the occurrence of prescribing at least one antibiotic drug for an URTI and the occurrence of prescribing two or more antibiotics for an URTI. GEE logistic regression models were used to examine the socioeconomic and demographic determinants of the above two outcome variables. Results: The percentage of prescribing at least one antibiotic for URTIs was 48.6% while the percentage of prescribing antibiotic combination (two or more antibiotics) was 4.6%. The two measurements of antibiotic utilization differed remarkably among the 10 provinces. Patients diagnosed with tonsillitis and faucitis had higher odds (OR = 8.86 for tonsillitis and OR = 4.64 for faucitis) of antibiotic prescription than patients with other diagnosis of URTIs. Patients with tonsillitis and faucitis also had higher odds (OR = 3.82 for tonsillitis and OR = 2.71 for faucitis) of multiple antibiotic prescription than those with other diagnosis of URTIs. The number of drugs per prescription and injection in prescriptions were also significant predictors of antibiotic and multiple antibiotic utilization for URTIs. Conclusion: It is concluded that the percentage of antibiotic prescription for URTIs is higher in rural Western China than in most of other countries with available data and that prescriptions of antibiotics for URTIs are associated with residence regions of patients, URTI diagnosis and background information on drug prescription.
8. Increased expression of the 20S proteasome in peripheral blood mononuclear cells of type 2 diabetic patients
Academic Journal of Xi'an Jiaotong University 2010;22(4):255-259
Objective: To investigate the dynamic expression of the 20S proteasome in peripheral blood mononuclear cells (PBMCs) of type 2 diabetic patients without vascular complications. Methods: PBMCs were prepared from 30 type 2 diabetic patients and 30 nondiabetic controls. The general indexes including weight, height and blood pressure were recorded. Fasting plasma glucose, fasting plasma insulin and glycosylated hemoglobin were measured. The protein level of the 20S proteasome was measured by Western blotting. The mRNA expression levels of the 20S proteasome β1, β2 and β5 submits were detected by real-time PCR. Results: Compared with that in the nondiabetic controls, the protein level of the 20S proteasome was significantly increased in the diabetic patients and was positively associated with glycosylated hemoglobin. Conclusion: Type 2 diabetic patients without vascular complications have an increased 20S proteasome expression, the significance of which needs to be explored by further study.
9. Inhibitory action of docetaxel on the proliferation of HeLa and SiHa cells
Academic Journal of Xi'an Jiaotong University 2010;22(4):260-264
Objective: To study the inhibitory action of docetaxel (DOC) on the proliferation of HeLa and SiHa cells. Methods: Cell morphological changes were observed with inverted phase contrast microscope. MTT was adopted to test and calculate the cell inhibition ratio. Flow cytometry was used to detect cell cycle. Results: DOC had an obvious concentration-dependent inhibitory effect on the proliferation of both HeLa and SiHa cells. The inhibition ratio of DOC on SiHa was significantly higher than that on HeLa (P<0.05). DOC blocked HeLa at G2/M phase. Under the effect of DOC, the cell cycle of SiHa was not changed much. Conclusion: DOC has an obvious inhibitory action on both HeLa and SiHa cells, which shows a promising prospect of DOC in clinical treatment of cervical cancer.
10. Family lifestyle factors related to children's congenital heart defects in China: A case-control study
Academic Journal of Xi'an Jiaotong University 2010;22(4):265-269
Objective: To explore the multiple risk factors for family lifestyle of children with congenital heart defects (CHDs) in Shaanxi Province, China. Methods: A 1:1 case-control study was carried out to investigate 60 pairs of children and their parents. The univariate and multivariable logistic regression models were used to analyze the influence of risk factors related to parents' lifestyle on CHDs. Results: Several possible risk factors were found for CHDs, including fever (OR = 4.465, P = 0.017), pesticides contact (OR = 2.234, P = 0.083), passive smoking during pregnancy (OR = 20.529, P = 0.007) and father's smoking (OR = 3. 342, P = 0.005); fever (OR = 2.428, P = 0.012) and passive smoking during pregnancy (OR = 1.201, P = 0.037) were also correlated with ventricular sepal defect (VSD). Conclusion: Fever, pesticides contact and passive smoking are associated with CHDs during pregnancy. We should focus our attention on health care during pregnancy to avoid the above-mentioned risk factors and call on parents to hold on to a good healthy lifestyle.