Biomedical subjects

Song Zhang

Publications and source records attributed to Song Zhang.

64 records · Page 4Linked to original sources

PubMed2002

Expression of tenascin and fibronectin in nasal polyps.

To explore the role of tenascin (TN) and fibronectin (FN) in the pathophysiology of nasal polyps (NP), the expression of TN and FN in NP from 34 patients and inferior turbinates from 20 patients with deviation of nasal septum was immunohistochemically studied. In patients with NP, the relations between expression and histopathological features, eosinophils (EOS) infiltration, clinical staging and the size of NP were analyzed. Our study showed that the gray score of TN and FN expression was 163.10 +/- 10.54 and 163.24 +/- 11.52 in NP respectively, whereas it was 175.49 +/- 9.29 and 173.93 +/- 7.92 in inferior turbinates respectively. The difference between two groups was significant (P < 0.01). The expression of TN and FN in endematous type was significantly stronger than that in cystic and glandular type and fibrous type (P < 0.05). The association between FN expression and EOS infiltration was significant (r = -0.60, P < 0.01). The expression of TN and FN did not correlate with clinical staging and size (P > 0.05). It was suggested that abnormal ECM might contribute to proliferation of epithelia, accumulation of EOS and edema formation, thereby causing development of NP.

Adolescent↗

PubMed2002

Determination of drug-protein interactions by microdialysis coupled with liquid chromatography and electrochemical detection based on a nickel hexacyanoferrate modified electrode.

Microdialysis sampling coupled with liquid chromatography-electrochemical detection (LC-ED) was developed and applied to determine the interaction of thiopurine (TP) with bovine serum albumin (BSA). A nickel hexacyanoferrate (NiHCNFe) modified electrode was fabricated and used as the working electrode in LC-ED for the determination of TP. Cyclic voltammetric experiments demonstrate that this chemically modified electrode (CME) can effectively catalyze the electrooxidation of TP. The mechanism of the catalytic oxidation of TP at the CME involves an 'EC' process. In the LC-ED, the CME also shows good stability and reproducibility for the determination of TP. The limit of detection is 5.0 x 10(-7) mol l(-1) for 6-TP with a signal-to-noise ratio of 3. The utility of microdialysis as a quantitative sampling technique for in vitro studies of drug-protein interactions was studied. The microdialysis experiments were performed in phosphate buffer solution (pH 7.4) containing different molar ratios of the drug and protein at 37 degrees C. The collected microdialysis sample with unbound TP was analyzed at the NiHCNFe CME in the LC-ED. The relative recovery of TP determined in vitro is 18.3% at a perfusion rate of 1.0 microl min(-1) and the RSD is about 2.1%. The association constant and the number of binding sites on a BSA molecule calculated with the Scatchard equation are 3.72 x 10(-3) (1 mol(-1)) and 1.51, respectively. This method provides a fast, sensitive and simple technique for the study of drug-protein interactions.

Allopurinol↗

PubMed2002

[Cytochrome P450 2C19 gene polymorphism in four Chinese nationality populations].

OBJECTIVE: To study the cytochrome P450 2C19(CYP2C19) gene polymorphism in 4 Chinese nationality populations. METHODS: The genotypes of the unrelated Miao, Buyi, Tu and Dulong subjects were analyzed by polymerase chain reaction and restriction fragment length polymorphism (RFLP). RESULTS: CYP2C19*2 allele frequencies were 0.291, 0.329, 0.315 and 0.349 in Miao, Buyi, Tu and Dulong population, respectively. The four populations were consistent with Hardy-Weinberg expectations (P>0.05). CONCLUSION: The frequencies of CYP2C19*2 were in agreement with those of other published data on Asian, but were different from those data on European and African.

Aryl Hydrocarbon Hydroxylases↗

PubMed2002

Clinical significance of cytogenetic analysis in chronic myeloid leukemia (with report of 155 cases).

OBJECTIVE: To explore the relation of cytogenetic changes in patients with chronic myeloid leukemia (CML) to the diagnosis, clinical staging and therapy protocol of the disease. METHODS: According to established diagnostic criteria, 155 CML patients were divided into 3 groups and 3 clinical phases were identified on the basis of their Sokal scores. The bone marrow was obtained for G banding and karyotype analysis. RESULTS: It was found that 148 patients (95.5%) carried Ph1 chromosome. Among the other 7 cases without Ph1 chromosome, 4 were identified as being bcr/abl fusion gene positive. The ratio of additional cytogenetic abnormalities were higher in patients in blast crisis or accelerated phase than in patients in chronic phase. CONCLUSION: CML consists of a group of diseases with high heterogeneity, and the prognoses of the patients mostly depend on the malignancy of the tumor. The occurrence of additional chromosomal abnormality is highly correlative with the risk index and clinical staging of the patients, which may serve prognostic purposes. Conventional cytogenetic analysis may help evaluate the therapeutic effect and make subsequent clinical decisions, and may also facilitate new karyotype identification.

Adolescent↗

PubMed2002

The expression of TNF-alpha mRNA and its significance in murine viral myocarditis.

OBJECTIVE: To study the change of serum tumor necrosis factor-alpha (TNF-alpha) and its mRNA in viral myocarditis (VMC) and its role in VMC. METHODS: The expression of TNF-alpha mRNA in VMC mice was studied by the way of RT-PCR. Changes of serum TNF-alpha on day 3, 5, 7, 9, 15 and 35 after virus inoculation in VMC mice were assayed using ELISA. The possible relationship of TNF-alpha and VMC was analysed. RESULTS: The expression of TNF-alpha mRNA in VMC mice increased apparently. The level of TNF-alpha mRNA expressed on the 7th day after virus inoculation (1.94) was higher than that on the 3rd day (1.09). Serum TNF-alpha of the VMC mice was higher than that of the control mice (127.2 +/- 13.8) from the 3rd to 35th day after virus inoculation (3rd day group 159.7 +/- 40.8, 5th day group 212.7 +/- 40.0, 7th day group 296.7 +/- 34.3, 9th day group 267.3 +/- 41.4, 15th day groups 187.8 +/- 49.6, and 35th day groups 155.4 +/- 35.9) and the peak expression was on the 7th day after the inoculation (P < 0.01 compared with the control group). CONCLUSIONS: Both serum TNF-alpha and its mRNA increased in murine VMC, which may take part in the pathogenesis of VMC.

Animals↗

PubMed2002

[Expression of extracellular matrix glycoprotein tenascin in the laryngeal cancer].

OBJECTIVE: Tenascin (TN) is an extracellular matrix glycoprotein upregulated in some pathological processes. In the study, we investigated its expression in the laryngeal epithelial lesions and explored the relation of TN with the laryngeal tumor. METHOD: Expression of TN were examined by immunohistochemistry SP method in sections of laryngeal lesions from 4 leukoplakia, 8 papilloma, 7 in situ carcinoma and 39 invasive squamous cell cancer patients. An automatic image analyzer was used to analyze the staining results. RESULT: No expression, of TN was found in the extracellular matrix of papilloma or leukoplakia. Only a weak stain was found at their epithelialstromal interface in seldom sections. There was a weak extracellular matrix stain of TN in all situ carcinoma and the stain difference between in situ cancer and papilloma or leukoplakia was significant (P < 0.001). There was a much stronger extracellular matrix stain in invasive cancer than that in situ cancer (P < 0.01). The differences of TN expression among different T stage and histological grade of invasive cancer were insignificant (P > 0.05). But there was a significantly stronger TN stain in the cases with lymph node metastasis than those without lymph node metastasis (P < 0.01). CONCLUSION: TN expression may be involved in the oncogenesis and metastasis of laryngeal squamous cell cancer. It was implicated that the risk of pre cancerous lesions progress to cancer.

Adult↗

PubMed2002

[Expression of tenascin and fibronectin in nasal polyps].

OBJECTIVE: To explore the role of tenascin (TN) and fibronectin (FN) in the pathophysiology of nasal polyp. METHODS: The expression of TN and FN in nasal polyps from 34 patients and in inferior turbinates from 20 patients with deviation of nasal septum was studied with immunohistochemical method. In patients with nasal polyps, the relations between expression and histopathologic characteristics, eosinophilias (EOS) infiltration, clinical staging and the size of nasal polyps were analyzed. RESULTS: (1) The gray score of TN and FN expression was 163.10 +/- 10.54 and 163.24 +/- 11.52 in nasal polyps respectively, whereas it was 175.49 +/- 9.29 and 173.93 +/- 7.92 in inferior turbinates respectively. The difference between two groups was significant(P < 0.01); (2) The expression of TN and FN in edematous type was significantly stronger than that in cystic fibrous and glandular type (P < 0.05); (3) The association between FN expression and EOS infiltration was significant(r = -0.60, P < 0.01); (4) The expression of TN and FN did not correlate with clinical staging and size(P > 0.05). CONCLUSION: Abnormal ECM may contribute to proliferation of epithelium, accumulation of EOS and edema formation, as a result, to enhance the development of nasal polyps.

Adolescent↗

PubMedDate not supplied

Interactive volume rendering of thin thread structures within multivalued scientific data sets.

We present a threads and halos representation for interactive volume rendering of vector-field structure and describe a number of additional components that combine to create effective visualizations of multivalued 3D scientific data. After filtering linear structures, such as flow lines, into a volume representation, we use a multilayer volume rendering approach to simultaneously display this derived volume along with other data values. We demonstrate the utility of threads and halos in clarifying depth relationships within dense renderings and we present results from two scientific applications: visualization of second-order tensor valued magnetic resonance imaging (MRI) data and simulated 3D fluid flow data. In both application areas, the interactivity of the visualizations proved to be important to the domain scientists. Finally, we describe a PC-based implementation of our framework along with domain specific transfer functions, including an exploratory data culling tool, that enable fast data exploration.

Algorithms↗

PubMedDate not supplied

CAVE and fishtank virtual-reality displays: a qualitative and quantitative comparison.

We present the results from a qualitative and quantitative user study comparing fishtank virtual-reality (VR) and CAVE displays. The results of the qualitative study show that users preferred the fishtank VR display to the CAVE system for our scientific visualization application because of perceived higher resolution, brightness and crispness of imagery, and comfort of use. The results of the quantitative study show that users performed an abstract visual search task significantly more quickly and more accurately on the fishtank VR display system than in the CAVE. The same study also showed that visual context had no significant effect on task performance for either of the platforms. We suggest that fishtank VR displays are more effective than CAVEs for applications in which the task occurs outside the user's reference frame, the user views and manipulates the virtual world from the outside in, and the size of the virtual object that the user interacts with is smaller than the user's body and fits into the fishtank VR display. The results of both studies support this proposition.

Data Display↗

PubMedDate not supplied

Use of cognitive enhancement medication in persons with Alzheimer disease who have a family caregiver: results from the Resources for Enhancing Alzheimer's Caregiver Health (REACH) project.

OBJECTIVE: Aging populations show increased prevalence of cognitive impairment and dementia. Recent efficacy studies report on prescription medications and herbal preparations that affect cognitive functioning, but the prevalence and correlates of cognitive-enhancement (CE) medication use among community-dwelling older persons is not well studied. The authors examined the frequency and appropriateness of use, the importance of a family caregiver in medication decisions for dementia patients, and differences in access to medical care. METHODS: REACH is a multisite feasibility study of several approaches to reducing the negative impacts of caregiving on those living with a family member with dementia. Data on medication use by care-recipients were collected at baseline and 1 year later. RESULTS: At baseline, 31% of 1,222 care-recipients were using a CE medication. Factors independently related to CE use were age, education, functional status, and caregiver vigilance. Within 1 year, 14% started and 30% quit taking CE. Care-recipients more likely to be Starters had spouse-caregivers, more education, and fewer baseline ADL impairments. Quitters had more ADL deficits at baseline and became less able to perform ADL at follow-up than those who continued on CE. CONCLUSIONS: CE medication use among dementia patients with a family caregiver is relatively common, though there is substantial geographic variability. Our findings are mixed with respect to appropriate use of CE medications, suggesting areas for physician education. Our data indicate the importance of the caregiver in CE medication use and suggest that there may be disparities in access to healthcare among people with cognitive impairment.

Adult↗