Search PubMed⌕ Search

Biomedical subjects

T Zhang

Publications and source records attributed to T Zhang.

At least 199 records · Page 11Linked to original sources
PubMed1999

[Study on the reversal of cancer multidrug resistance by Chinese medicine Fw13-te41 in nude mice].

We have reported that three reversal agents were sifted out from 32 Chinese galenicals through a series of cell culture tests. Among them, Fw13-te41 has the best effect of reversal cancer multidrug resistance (MDR) in vitro. In this study, the reversal action of Fw13-te41 in vivo was studied on the animal model of nude mice with human leukemia k562/ADR. Twenty SPF BALB/c-nu/nu nude mice with xenograft tumor were randomly divided into the control group (n = 6), VCR group [intraperitoneal (i.p.) VCR 250 micrograms/week, n = 5], VCR + Fw13-te41 group (i.p VCR 250 micrograms/week + Fw13-te41 0.2 ml/day, equivalent to crude drug 10 g/kg, n = 5), and Fw13-te41 group (i.p Fw13-te41 0.2 ml/day, equivalent to crude drug 10 g/kg, n = 4). After 18 days, the rate of tumor inhibition (RTI) of VCR group was 19.79%, but the RTI of VCR + Fw13-te41 group was as high as 86.95% (P < 0.05). There results demonstrate that the Chinese medicine Fw13-te41 has an evident reversal action of malignancy MDR in vitro and in vivo.

Animals↗
PubMed1999

Dietary L-arginine attenuates expression of vascular cell adhesion molecule-1 in the aortae of hypercholesterolemic rats.

OBJECTIVE: To determine whether the antiatherogenic effect of L-arginine is due to an inhibition of vascular cell adhesion molecule-1 (VCAM-1) expression in the aortae of hypercholesterolemic rats. METHODS: Twenty-four male Wistar rats were randomized into three groups: Group NC with normal diet (NC, n = 8), Group CC with 4% cholesterol and 1% cholic acid diet (CC, n = 8), Group AC with 4% cholesterol and 1% cholic acid diet supplemented with 3% L-arginine HCl in the drinking water (AC, n = 8). Eight weeks later, the blood samples were collected for biochemical studies, and the aortae were harvested for RT-PCR and immunohistochemical studies. RESULTS: The results showed that dietary L-arginine supplementation reduced expression of VCAM-1 in protein level and mRNA level. CONCLUSION: Inhibitory effect of dietary supplementation of L-arginine on VCAM-1 expression may be one of the mechanisms of its antiatherosclerosis.

Animals↗
PubMed1999

Quantitative assessment of Parkinson's disease deficits.

OBJECTIVE: To quantitatively analyze the tremor and rigidity due to Parkinson's disease. METHODS: 38 patients with Parkinson's disease (PD) ranging in age from 45 to 72 years and 211 normal subjects aged from 16 to 76 years were investigated. The frequency and range of tremor, the muscle tone of the upper limbs in elbow were detected by a computerized video motion detecting system and a new invented apparatus which can detects skeletal muscle tone. RESULTS: For the PD patients, the frequency of resting tremors was detected in 4 to 6 per second. For extensor and flexor in the PD patients, the value of muscle tone was higher than that of normal subjects and the value of muscle tone in flexor was higher than that of extensor. The rigidity increased gradually with repeat passive movement. The curves of rigidity were shown on computer screen or printed out. The data of rigidity were compared with the M-A Scale. A patient who was suspected to suffer from PD above by the equipments and found the muscle tone was higher than normal. In another PD patient the rigidity was obvious at one side and the muscle tone in "normal side" was also high. These equipments were used to record changes of rigidity and tremor in one more PD patient taking with different drugs in order to see the drug effect. CONCLUSION: Quantitative methods are useful to analyse the motion disorders due to PD.

Aged↗
PubMed1999

[Studies on the expression of complement regulatory proteins in three kinds of stem cell defect anemias and its clinical implications].

OBJECTIVE: To investigate the expression of membrane associated complement regulatory proteins (CRP)--CD55 and CD59 on the peripheral blood cells in patients with paroxysmal nocturnal hemoglobinuria (PNH), aplastic anemia(AA) and myelodysplastic syndrome (MDS) and its clinical implications. METHODS: Expression of CD55 and CD59 on neutrophils, lymphocytes and erythrocytes was analyzed with flow cytometry, using FITC and PE labeled anti-CD55 and CD59 monoclonal antibodies. RESULTS: CD55 and CD59 expression on neutrophils was significantly decreased in 21 PNH patients (including 2 cases of AA-PNH syndrome). CD59- cells in neutrophils were constantly in excess of 10% in all of the PNH patients. Reduction in CD59 expression on erythrocytes was related to the severity of the disease. CD55- neutrophils were also significantly increased in PNH patients but with a greater variation. Expressions of CD55 and CD59 on neutrophils were remarkably decreased in 31 AA patients but to a less extent as compared to PNH. No significant difference in the expressions of CD55 and CD59 was found in all the 21 MDS patients. CONCLUSION: Expression of CRP is reduced in PNH and its related disorder-AA but remains unchanged in MDS. Flow cytometric analysis of complement regulatory proteins is of value in diagnosis and differential diagnosis of PNH, AA and MDS. In terms of diagnostic sensitivity and specificity, CD59 is superior to CD55, and neutrophil is superior to lymphocyte and erythrocyte.

Adolescent↗
PubMed1999

[Telomerase activity in breast carcinoma].

OBJECTIVE: To investigate the significance of telomerase activity in breast carcinoma with respect to axillary lymph node status. METHODS: Telomerase activity was analyzed in 88 breast carcinomas specimens and 16 benign breast lesions, using PCR-based telomeric repeat amplification protocol (TRAP) assay. RESULTS: Telomerase activity was detected in 75 (85.2%) of 88 breast carcinomas (including three breast carcinomas in situ which were all positive for telomerase activity), whereas in benign breast lesions analyzed only 2 (12.5%) of 16 cases were positive (P < 0.001). Besides, telomerase activity was significantly higher in node-positive breast carcinomas (93.2%) than in node-negative ones (77.3%, P < 0.05). CONCLUSION: The results suggest that telomerase activation plays an important role during breast carcinoma progression. It may serve as an early marker of breast carcinoma.

Biomarkers, Tumor↗
PubMed1999

[Expression of metastasis suppressor gene nm23-H1 in oral squamous cell carcinoma and its relation to tumor prognosis].

OBJECTIVE: To study the relation between the expression level of nm23-H1 protein and prognosis of oral squamous cell carcinoma (OSCC). METHODS: The expression of nm23-H1 protein in 75 cases of OSCC, 27 cases of oral mucosa, 9 cases of cervical lymph-node metastases by immunohistochemical technique (SABC), and the relation between nm23-H1 protein expression level and prognosis of OSCC was evaluated by chi-test and single-factor, multi-factor Cox proportional hazards regression model analysis. RESULTS: These immunoreactivities of nm23-H1 protein were mostly in the cytoplasm of tumor and epithelial cells. There was a significant difference of nm23-H1 protein expression level between three-year survival and seven-year survival group (P < 0.05), and there was a relation between nm23-H1 protein expression level and prognosis of OSCC in single-factor Cox analysis. But no relation was found between nm23-H1 protein expression level and prognosis in multi-factor Cox analysis. CONCLUSION: nm23-H1 protein expression level was probably not a valuable predictor of OSCC patients' prognosis. It may indirectly affect OSCC prognosis through its effect on OSCC metastasis.

Carcinoma, Squamous Cell↗
PubMed1999

[Study on relationship between insulin-resistance and syndrome differentiation typing in hypertensive patients].

OBJECTIVE: To find the relationship between insulin-resistance and Syndrome Differentiation typing (SDT) in hypertensive patients. METHODS: Two hundred and nine patients of early stage hypertension with no complication of heart, brain or kidney were selected and classified into 4 types according to SDT, the Liver-Fire exuberant type (A), the Phlegm-Dampness abundant type (B), the Yin-Deficiency and Yang-Excess type (C) and the both Yin-Yang Deficiency type (D). Their insulin sensitivity were examined and compared with that of 40 healthy subjects. RESULTS: (1) Compared with healthy subjects, all hypertensive patients had apparent insulin resistance (P < 0.05). If the insulin sensitivity of healthy subjects was defined as 1, that of patients of type A, B, C and D were 0.54, 0.58, 0.65 and 0.80 respectively. (2) Comparison between the insulin sensitivity of type A, B and C showed no significant difference, while they were compared with type D, the difference was significant (P < 0.05), that is, the insulin sensitivity of type D was close to that of healthy subjects. (3) The fasting blood insulin of type D was obviously lower and the insulin sensitivity of type D was obviously higher than that of the other three types (P = 0.0001). (4) After adjusting age, sex and body mass indexes, multivariate regression analysis demonstrated that insulin sensitivity was closely correlated with SDT (P = 0.0001). CONCLUSION: Insulin resistance is one of the pathological basis for SDT in hypertension.

Adult↗
PubMed1999

[Clinicopathological study of mucosa-associated lymphoid tissue lymphoma of salivary glands].

OBJECTIVE: To study the histopathological features and pathogenesis of mucosa associated lymphoid tissue lymphoma (MALT-oma) of salivary glands. METHODS: Surgical specimens from 27 cases of MALT-oma of salivary glands were studied using paraffin-embedded section, immunohistochemical method (SP method) and electron microscope. RESULTS: 12 tumors were located in the pariotid glands, the other 15 in the submandibular glands. Much of the MALT-oma of the salivary glands were composed of diffuse centrocyte-like (CCL) cells with "lymphoepithelial lesions". Immunohistochemically, CD20 expression was found to be positive and CD45RO expression was negative in all MALT-omas of salivary glands. CONCLUSIONS: Most of the MALT-omas are low grade malignant tumors and the tumor cells have a "homing back" phenomenon. A small number of MALT-omas can become highly malignant tumors with poor prognosis. Acquired MALT may develop as a reaction to autoimmune disease and/or infection. Hyperimmune reaction and MALT hyperplasia under continuous stimulation may result in myoepithelial sialadenitis and develop into MALT-oma of salivary glands.

Adolescent↗
PubMed1999

[mRNA and protein expression of apoptosis-regulating gene bcl-x in lymphomas].

OBJECTIVE: To observe mRNA and protein expression of bcl-x and explore the role of bcl-x in the regulation of apoptosis and oncogenesis and their value in differential diagnosis of lymphomas. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) and citric acid-microwave-ABC immunohistochemistry (ICH) were used to observe mRNA transcription forms and protein distributions of bcl-x in 30 frozen tissues and 109 paraffin embedded tissues (both including reactive hyperplasia and common types of lymphoma). RESULTS: RT-PCR revealed that all 30 frozen cases showed bcl-x transcription, of which 29 had bcl-x1 band and 13 had bcl-xs band. Bcl-x1 band was always stronger than bcl-xs band. IHC found that 97/109 cases had fine positive bcl-x granules in the cytoplasm. In lymphoid reactive hyperplasia, bcl-x exhibited weak immunoactivity in cells located in the germinal centers and interfollicular regions of the nodes but not in the mantle zone lymphocytes which surround germinal centers. In lymphomas, bcl-x immunoactivity was always strong and diffuse. The staining fractions in different types of lymphomas were significantly higher than those in lymphoid reactive hyperplasias (P > 0.05), but no significant difference was found between the positive rate and staining fraction of different types of lymphomas. CONCLUSION: Bcl-x shows active mRNA transcription and high protein expression in lymphomas. The long isoform of bcl-x (bcl-xl) is the predominant expression. The characteristics of bcl-x protein expression may be helpful in differential diagnosis of reactive hyperplasia and lymphoma.

Apoptosis↗
PubMed1999

[Histological grading in ductal carcinoma in situ of the breast].

OBJECTIVE: To study the significance of histological grading as a prognostic factor in ductal carcinoma in situ of the breast. METHODS: According to Van Nuy's classification, 32 cases of ductal carcinoma in situ (DCIS) of the breast were divided into three grades. RESULTS: Low grade (well differentiated, low grade DCIS) 12 patients (37.5%); Intermediate grade, 9 patients (28.1%); High grade (poorly differentiated DCIS) 11 patients (34.4%). Among the high grade DCIS, the histological subtypes were comedo (9 patients), micto papillary (1 patient) and solid (1 patient). The positive expression of c-erbB-2, p53 and MIB-1 in high grade DCIS was higher than that in intermediate and low grade DCIS. The difference between high grade and low grade DCIS was significant (P < 0.05). The expression of ER in high grade DCIS was lower than that in intermediate and low grade DCIS. CONCLUSIONS: Histological grading of breast ductal carcinoma in situ may be a good prognostic factor.

Adult↗
PubMed1999

[Molecular cloning of rat OB gene and its expression in Escherichia coli].

In order to provide rat OB gene product for studying the relationship between obesity and noninfectious diseases, rat OB cDNA was amplified by RT-PCR technique. 460 bp fragment of OB cDNA was subcloned into EcoRI/BamHI site of plasmid pUC 19. Sequence analysis of OB cDNA revealed that the translation reading frame was identical with that reported in the literature. Thereby plasmid pBV220-rOB was constructed and the specific expression of OB gene in E. coli identified by SDS-PAGE electrophoresis was obtained.

Amino Acid Sequence↗
PubMed1999

[Study of rhinophysiology for normal young adult in the Cantonese of China by acoustic rhinometer].

OBJECTIVE: In order to study the site of nasal parameters, nasal minimal cross-sectional area (NMCA), nasal cavity volume (NCV), nasal resistance (NR) and the relations among them. METHOD: 276 younger adult of normal Cantonese were tested by ECCOVISION acoustic rhinometer. RESULT: The results were as follows: 72.95% NMCA in subjects are positioned at internal nostril. The distance from the position of NMCA to the nostril is 1.36 +/- 0.53 cm in male, and 1.06 +/- 0.46 cm in female. There was no difference in NMCA, NCV and NR between male and female. There was significant relationship between the NR and NMCA. There was relationship between the NR and NCV, and there was little relationship between the NR and DCAN. CONCLUSION: Acoustic rhinometry is a new objective rhinometric method, but different race must have its standard respectively.

Acoustics↗
PubMed1999

[Expression of nm23-H1 gene in oral squamous cell carcinoma and its relation to tumor metastasis].

OBJECTIVE: To make an inquiry into the relation between the expression level of nm23-H1 protein and metastasis of oral squamous cell carcinoma (OSCC). METHODS: We evaluated the expression of nm23-H1 protein in 75 cases of OSCC by immunohistochemical technique (SABC). RESULTS: These immunoreactivities of nm23-H1 protein were most common in the cytoplasm of tumor and epithelia cell. Using single-factor chi-test, we found there was a significant correlation between the expression of nm23-H1 protein and lymph node metastasis of OSCC (P < 0.01), pathology grade (P < 0.05). But no statistical association was found among nm23-H1 protein expression level and tumor size, site and patient's sex, age. Using multi-factor logistic stepwise regression analysis, we found that nm23-H1 protein expression level had more effect on OSCC cervical lymph node metastasis than any other parameters. CONCLUSIONS: The results suggested that nm23-H1 protein play an important role in the suppression of the metastasis of OSCC, and that determining the expression level of nm23-H1 protein may help us prognose the metastasis of OSCC.

Adult↗
PubMed1999

[Clinical analysis of traumatic optic nerve dysfunction].

OBJECTIVE: To evaluate the key factors in diagnosis, treatment and prognosis of optic nerve trauma at the canalicular segment. METHODS: Twenty-six patients with optic nerve dysfunction resulted from trauma to the nerve at canalicular segment were analyzed. All the patients received orbital CT scans, corticosteroid therapy and surgical optic canal decompression through the external ethmoid approach. RESULTS: With the help of CT scan, the total diagnostic rate was 66.7%; that for canal fracture was 81.3%, for nerve swelling 56.3%. The improvement rate of surgical decompression depended on the time of visual loss and types of toauma. Specifically, the improvement rate was 57.1% in patients with visual loss occurred immediately after the trauma, 83.3% in patients with visual loss occurred a moment after the trauma, 66.7% in patients with optic nerve swelling and 56.3% with optic canal fracture. The possibility of recovery decreased with delay of the surgery. CONCLUSION: Orbital CT scan facilitates the diagnosis of optic canal fracture. However, the possibility of traumatic optic nerve dysfunction can not be ruled out in patients without the sign of canal fracture in the CT scan. The key factors in determining nerve recovery were associated with the severity of optic nerve trauma and the chance of surgery. Serious trauma and delay of the surgery may result in the blindness.

Adolescent↗
PubMed1999

[Study on the association between squamous cell carcinoma of larynx and HPV subgene by PCR].

OBJECTIVE: To measure the human papilloma virus(HPV) HPV-E1 in squamous cell carcinoma of larynx. METHODS: Polymerase chain reaction(PCR) was used to detect the HPV subgene in 25 specimens of laryngeal carcinoma and 6 normal larynges. RESULTS: Positive expression of HPV-E1 was detected in 17 of 25 cases(68%) with squamous cell carcinoma and all the recurrent cases. However, there was no positive expression of HPV-E1 in the normal larynges (P < 0.01). The expression rate was not significantly different among the histological grad groups. CONCLUSION: HPV-E1 infection was found in laryngeal carcinoma but not related to its histologic grading.

Carcinoma, Squamous Cell↗
PubMed1999

The diagnosis and treatment of gastrinoma: report of 17 cases.

OBJECTIVE: To study the experience of diagnosis and treatment of gastrinoma. METHODS: A retrospective study of 17 patients with gastrinoma seen from 1978 through 1998 in PUMC hospital. RESULTS: Three of the 17 cases were associated with multiple endocrine neoplasia type I (MEN-I) syndrome. Tumors dispersed extensively in pancreas (31%), duodenum (25%), lymphnode (19%) and other place (25%). Ultrasonography and computed tomography (CT) were sensitive in localizing tumor in pancreas and liver, but were not so well for small tumor in duodenum and lymph node. The angiography, percutaneous transhepatic portal sampling (PTPS), scintigraphy and endoscopic ultrasonography (EUS) also can be used. Sixteen of 17 patients underwent 38 operations and 56 percent of the 16 cases underwent several operations. Seven patients at last performed total gastrectomy that was still considered as a choice of treatment. Tumor resection was rare because the advancing of tumor in most cases. CONCLUSIONS: Diagnosing gastrinoma in its early stage and striving for the tumor resection and reducing the metastasis of liver were the cruxes for good prognosis.

Adolescent↗