Biomedical subjects

X Zhou

Publications and source records attributed to X Zhou.

At least 541 records · Page 30Linked to original sources

PubMed1997

[Effect of calcium and angiotensin II receptor on angiotensin II-stimulated protein synthesis in neonatal myocardial cells].

In this study, the role of angiotensin II (Ang II) receptor, Ca2+ in the Ang II-stimulated neoeatal myocytes protein synthesis were investigated and the effect of Ang II on expression of c-fos gene was observed. The results showed that the stimulatory effect of Ang II on protein synthesis was blocked by the Ang II antagonist-[Sar1 Ile8] Ang II. When verapamil, EG-TA, dantrolene, and Fura-2/AM, were added to the medium, the 3H-leucine incorporations stimulated by Ang II were reduced by 17%, 19%, 22%, and 27%. Using calcium ionophore-A23187 did not stimulate protein synthesis, but enhanced Ang II-induced 3H-leucine incorporation. In addition, Ang II could induce expression of c-fos gene. These results indicated that the hypertrophic effect of Ang II on the myocytes was mediated by Ang II receptor and depended on increase in [Ca2+]i and may be associated with enhanced expression of c-fos.

Angiotensin II↗

PubMed1997

[The association between vitamin D receptor gene polymorphisms, bone mineral density and osteocalcin in Chinese women].

OBJECTIVE: To investigate the correlations between vitamin D receptor (VDR) gene polymorphisms, and bone mineral density (BMD) as well as osteocalcin. METHODS: We used PCR-RFLP and Southern hybridization analysis to determine VDR genotypes in 202 Chinese women. BMD was measured by dual-energy X-ray absorptiometry (DEXA) and serum osteocalcin level was determined by radioimmunoassay. Analysis of covariance was used to test differences in mean BMDs across genotypes. RESULTS: We realized that VDR genotype frequencies in Chinese women were apparently different from those of Caucasians. In group of postmenopausal women, "bb" or "aa" genotype was related to lower BMD in Femoral Neck and Trochanter. No association was found between VDR genotypes and the serum osteocalcin level. CONCLUSION: There was some association between VDR genotypes and BMD in Chinese women. Its function in predicting osteoporosis still requires further study.

Adult↗

PubMed1997

[Separation and purefied of calf osteocalcin, set up radioimmunoassay for osteocalcin].

OBJECTIVE AND METHODS: We extracted and purified osteocalcin (BGP) from calf femur by gel filtration, FPLC and HPLC subsequently. The rabbits were immunized by this antigen and produced antibody. With this antibody (final 1: 35,000 dilution) we established RIA for BGP. This assay is stable and sensitive, the kd was 2.29 x 10(11). The intra assay variation was 2.1% and the inter assay variaton was 5.6%. It has no crossreaction with insulin, parathyroid hormone or calcitonin. RESULTS: The serum BGP values were detected in normal subjects and six kinds of bone metabolic diseases. In 81 normal subjects, the average serum BGP level was (5.3 +/- 1.5) ng/ml and in postmenopausal osteoporosis the serum BGP level [(6.2 +/- 1.9) ng/ml, n = 42] was higher than the normal (P < 0.05). The serum BGP levels were increased much in primary hyperparathyroidism [(12.8 +/- 7.0) ng/ml, n = 21, P < 0.001]. Increased values of BGP were also found in patients with chronic renal failure [(8.5 +/- 2.4) ng/ml, n = 18, P < 0.01] and Paget's disease [(6.7 +/- 2.2) ng/ml, n = 12, P < 0.05]. Decreased serum BGP values were found in Cushing syndrome [(2.9 +/- 0.9) ng/ml, n = 16, P < 0.001] and hypoparathyroidism [(3.4 +/- 1.1) ng/ml, n = 42, P < 0.001]. This result showed that in diseases with high bone turnover, the serum BGP levels were increased and in diseases with low bone turnover, the serum BGP levels were decreased. CONCLUSION: The data suggest that serum BGP is a sensitive marker for bone turnover. It is very improtant in studying bone metabolic diseases.

Adult↗

PubMed1997

[Mandibular ridge augmentation by sandwich osteotomy and BMP-HA implantation].

In order to solve a series of problems ridge augmentation by subperiosteal implantstion, HA combined with BMP was implanted in between the two pieces of mandible produced by osteotomy. Nine adult mongrel dogs were used in this study and six patients were treated with this mathod. The specimens were examined by light microscope, scanning electron microscope in the experimental study. The results show that there are a large amount of new bone formation both within and around the combined material. The amount is increasing as the time lapsed and the new bone is connected directly with the host bone of two side. Clinical application showed that after augmentation of the atrophic alveolar ridge with this mathod, the shape and volume of the alveolar ridge were good. The retention and stability of the lower denture was improved significantly. The results showed that this method of alveolar ridge augmentation has many advantages.

Alveolar Process↗

PubMed1997

[Serial modifications of bacon's pull through resection for low rectal cancer].

Four modifications of Bacon's pull-thru resection were undertaken to improve postoperative defecatory control and to avoid the 2nd stage resection of the pull-thru colon stump. 54 cases of modified Bacon's rectal resection (9.64% of sphincter saving resections) were performed between 1954-1989. The 1st modification (1954) preserves the levator ani and the intact anorectal ring. The 2nd modification (1964) preserves the dentate margin and anal transitional zone (acute anal sensation), thus greatly improving defecatory control. The 3rd modification (1980) simplified intraanal resective procedure. The 4th modification (1991) was to encircle and ligate the distal end of colon over a sterilized corrugated intraluminal splinting tube (The other end of which is already connected to a long latex tube prior to operation). The latex tube was pulled out thru anus, until the colonic ligature reaches the Dentate margin, to substitute for colonic pull-thru and to divert feces during & after operation, 4-8 fine stitches approximate the colon wall 1 cm proximal to the ligature, to the cut edge of anal mucosa. The colon wall distal to the ligature sloughed in 7-10 days, the proximal colon has partially healed to the raw areas of anal canal without infection. The 2nd stage colon stump resection is thus obviated and hospitalization shortened. The postoperative anal function was good in 86.66%. Modified Bacon's operation is indicated for very low rectal cancer when the rectal remnant above levator ani after adequate resection is less than 1 cm which is difficult for intraabdominal anastomosis. It extends the scope of sphincter-saving operation. It is a good substitute for Park's coloanal anastomosis.

Defecation↗

PubMed1997

[Characteristics of lip-mouth region in smiling position from 80 adults with acceptable faces and individual normal occlusions].

The Characteristics of Lip-mouth region including the soft and hard tissues in smiling position with frontal fixed position photographic computered analysis was studied. The examples were 80 adults (40 males and 40 females) with acceptable faces and individual normal occlusions. The age was between 17-25 years of age. The method adopting maximum smiling position to study the lip-mouth region is scientific, and the maximum smile line could be divided into three categories: low smile line-a-counted for 16.25% of the total samples; average smile line--68.75%; high smile line--15%.

Adolescent↗

PubMed1997

[The immune response in rats immunized systemically by the surface protein antigen P1 from streptococcus mutans conjugated with procholeragenoid].

This study was carried out to observe the antibody responses in rats after they were immunized with the surface protein P1 of streptococcus mutans when a special adjuvant was used. Antigen P1 was conjugated covalently with procholeragenoid (PCG), and then Sprague Dawley rats were immunized with P1 or the conjugated antigen P1-PCG subcutaneously or intragastrically. Anti-P1 antibody level was assayed at different time points by ELISA. The results showed that the levels of anti-P1 SIgA antibody in saliva rose when P1-PCG was given subcutaneously or intragastrically; the antibody level following the subcutaneous injection was higher and lasted longer, compared with that following the intragastric administretion. The level of anti-P1 IgG antibody in serum only rose when the rats were immunized subcutaneously. These results implied that mucosal immune response or humoral immune response could be induced subcutaneously when PCG was used as an adjuvant.

Animals↗

PubMed1997

[High performance liquid chromatographic determination of quercetin in the extract of Ginkgo biloba L. leaves].

This paper reports the HPLC determination of one of the flavones quercetin in the extract of Ginkgo biloba leaves. Quercetin was separated completely on an YWG-C18 column(0.46 cm x 15 cm), using a mixture of methanol, water and phosphoric acid(50:49.8:0.2) as mobile phase, with UV detection at 360 nm. The results have shown the recoveries to be between 95.3%-103.2% and RSD 1.86%.

Chromatography, High Pressure Liquid↗

PubMed1997

[Molecular biology studies on metalloproteinase and tissue inhibitor of metalloproteinase expression in salivary adenoid cystic carcinoma].

In order to research the relation between metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) and metastasis of salivary adenoid cystic carcinoma (ACC). We use dot blotting to analyse the expression of MMP-2, MMP-9 and TIMP-2 in ACC-2, a cell line of ACC in palate and ACC-M, a high lung metastasis clone which cloned from ACC-2. The result showed the expression of MMP-2 and MMP-9 were higher in ACC-M than that in ACC-2, but the expression of TIMP-2 were higher in ACC-2 than that in ACC-M This suggest MMP-2 and MMP-9 can promote ACC metastasis, TIMP-2 can suppress ACC metastasis. MMP and TIMP maybe a key mechanism of ACC metastasis.

Carcinoma, Adenoid Cystic↗

PubMed1997

Study on small hepatocellular carcinoma and its extension.

This paper summarizes the "study on small hepatocellular carcinoma and its extension" in Liver Cancer Institute, Zhongshan Hospital of Shanghai Medical University during the past 25 years. The results indicated that it was an important approach to obtain long-term HCC survivors, of the 239 patients with 5-year survival, small HCC resection accounted for 51.4%. It was an effective approach to improve the prognosis of HCC in the entire series, the 5-year survival of inpatients treated in authors' institution was 4.8% in 1958-1970, 12.2% in 1971-1983, and 46.7% in 1984-1995; which were correlated to the increase proportion of small HCC resection in the series; it was more effective as compared to large HCC resection, the 5 year survival was 61.3% (n = 645) versus 33.6% (n = 950). Extensions of small HCC study included early detection and treatment of small recurrent HCC, of the 147 patients with re-resection, the 5-year survival was 48.9% calculated from the time of first resection. Another extension was conversion of large HCC into small HCC, using multimodality combination treatment, 72 out of the 663 patients with surgically verified unresectable HCCs have been converted to resectable, 5-year survival being 62.1%, which was comparable to that of small HCC resection. Studies on related basic aspect of small HCC such as cell origin of recurrence, and molecular aspect of small HCC, indicated that biological characteristics, particularly the tumor invasiveness, remained the key link for further prolong survival after small HCC resection. Recently, a "patient-like" human HCC metastatic model in nude mice has been established. Experimental interventions have also been tried. Clinical trials for prevention of recurrence after small HCC resection have shown preliminary encouraging results. However, the "cost-effectiveness" of screening, the invasiveness of HCC, the multicentric origin, the coexisted Child C cirrhosis, etc., remained great challenge.

Animals↗

PubMed1997

[Effects of different dilution of specific antibodies against the cell surface protein P1 of S. mutans MT 6R upon its adherence].

The sera and saliva were obtained from BALB/C mice by injection of the cell surface protein P1 and Freud's adjuvant. High antibody titers were showed in the sera and saliva by an enzyme-linked immunosorbent assay. Different dilution of the specific antibodies against the protein P1 of S. mutans had different inhibition effects on adhering of S. mutans MT 6R. Adherence of streptococcus mutans MT 6R on saliva-coated hydroxyapatite was reduced significantly by using sera and salivary antibodies in dilution of 1:1, 1:2, 1:4, 1:8, 1:16, 1:32 (P < 0.05).

Animals↗

PubMed1997

[Comparison of the activity for carbohydrate metabolism enzymes of plaque in different ages].

Plaque samples were collected from tooth surface by the sampling method in 28 volunteers (two groups, 14 young people, ages ranged from 19-26 years, mean: 22.29 years old; 14 old people, aged between 60-70 years, mean: 64.35 years old, DMFT > 3). The activity for three enzymes including amylases, LDH, GTF was tested by micro-chemistry enzyme analysis method. The results showed that there were no significant difference for the activity of three enzymes in two groups (P > 0.05). The finding suggests that dental plaque is a specific microecologic environment and cariogenic factor, age does not affect the activity of enzymes, plaque in different ages has similar cariogenicity.

Adult↗

PubMed1997

[A primary observation of the active immune prevention effects against dental caries using the streptococcus mutans surface protein P1 in rats].

To observe the anti-caries effects of a small dose of the surface protein antigen P1. The SD rats were immunized with P1-CTB and P1-PCG through IN (intranasal immunization) and IG (intragastric immunization). The results showed that caries was reduced heavily. There was no obvious difference between IN and IG. P1-CTB and P1-PCG can be used as an antigen to prevent the dental caries, but much further research work still need to do.

Animals↗

PubMed1997

[Simulation study on the blood volume feedback control].

To describe the relationship between blood volume and the cardiac function mathematically, a computer cardiovascular model, was developed including a systemic circulation, a heart and a pulmonary model and a blood volume feedback control. Simulation results indicate that the chronic heart failure could be compensated by increasing the blood volume to maintain the proper arterial pressure. Deterioration in heart failure causes an increase in blood volume, as well as increases in heart volume and cardiac energy consumption. These results are in agreement with the clinical data and results reported in the literature. The simulation also shows that for a predetermined ventricular contractility, an adequate increase in blood volume will increase the heart volume but decrease the cardiac energy consumption and lead the heart to work in an optimum condition.

Aerospace Medicine↗

PubMed1997

[Clinical and pathological study on liver fibrosis in viral hepatitis].

49 patients with viral hepatitis were studied on the correlationship between liver fibrosis and the level of serum precollagen type III (PC III), pre-collagen III pre-peptide (P III P), Laminin (LN), hyaluronic acid (HA) and collagen type IV (IV-C), as well as relationship between them and the expression of LN, IV-C, a-smooth muscle actin (a-SMA) and cytokeration (CK) in the liver tissues examined by immunohistochemistry. Results showed that the level of PC III, P III P, LN, HA and IV-C in the groups of liver cirrhosis and chronic severe hepatitis were higher than that in the groups of acute and chronic hepatitis. High correlation was found between the level of these markers (especially the level of the IV-C) and the degree of fibrosis in the group of chronic hepatitis. So were the expression of LN, IV-C, a-SMA and CK in the liver tissue. The results also showed that the liver fibrosis correlated with inflammatory reaction in the liver. So the authors suggested that more attention should be paid to the inflammatory reaction of the liver for prevention and treatment of liver fibrosis.

Adolescent↗

PubMed1997

[Cord blood plasma selectively stimulates the expansion of hematopoietic pregenitor cells in vitro].

OBJECTIVE: To explore the effect of cord blood (CB) plasma on the expansion of hematopoietic progenitor cells. METHODS: The effect of CB plasma on the expansion of CB and bone marrow (BM)-derived hematopoietic progenitor cells was studies and compared with those of adult's peripheral blood (PB) plasma and cytokines such as IL-3 and SCF. RESULTS: (1) CB plasma increased CFU yields of CB-derived progenitor cells by 2.23 +/- 0.52-fold and this expansion was dependent on CB plasma concentrations supplemented in the cultures. Greater expansion of progenitor cells was found when ABO was unmatched between the CB-derived cells and CB plasma. (2) Stimulating effect of CB plasma on BM-derived progenitor cells was also related to ABO type. CFU yields were increased by 1.55 +/- 0.43-fold when ABO was unmatched and not increased when ABO was matched. (3) Expansion of CB-derived progenitor cells by IL-3 and SCF was revealed. Significant increase in CFU yields occurred in the addition of both the cytokine and the CB plasma. (4) No expansion occurred in CB-and BM-derived cell cultures supplemented with PB plasma. CONCLUSION: There is factor(s) selectively stimulating expansion of progenitor cells in CB plasma. It may be beneficial that CB plasma was transfused with CB-derived stem cell transplantation.

Animals↗

PubMed1997

[Correlation between the serum levels of interleukin-2 and soluble interleukin-2 receptor and the response to immunosuppressive therapy in severe aplastic anemia patients].

OBJECTIVE: To explore factors influencing the effectiveness of immunosuppressive therapy in severe aplastic anemia (SAA). METHODS: The serum levels of interleukin-2 (IL-2) and soluble IL-2 receptor (sIL-2R) of 22 SAA patients and 15 normal controls were measured by immunoenzyme assay. RESULTS: Comparing with the normal controls, 40.9% and 63.6% of the SAA patients had higher serum levels of IL-2 (>840ng/L) and of sIL 2R (>320 x 10(3) U/L), respectively. Those who had higher IL-2 levels and higher sIL-2R levels got better responses to cyclosporin A(CsA) and CsA plus antilymphocyte globulin (ALG). CONCLUSION: The serum levels of IL-2 and sIL-2R were correlated with the responsiveness to immunosuppressive therapy in SAA patients and might be useful for directing treatment.

Adolescent↗

PubMed1997

[Effects of antisense oligodeoxynucleotides targeting multidrug resistance gene on resistant cell line K562/ AO2].

OBJECTIVE: To investigate the reversal effect of antisense oligodeoxynucleotide on human multidrug-resistant leukemic cell line K562/AO2. METHODS: Antisense oligodeoxynucleotides (AOD) targeting-6 approximately 9 sites of exon 2 in human multidrug resistance gene(mdr-1), one of which is sequence-strict-complied and linked with polyethyleneglycol (PEG) at 5' end (AP, 15 mer), the other lacks nucleotide complied site-1 (AP', 14mer), were synthesized. AP, AP' and verapamil were simultaneously added to human mdr-1-mRNA positive leukemia cell line K562/AO2 and, mdr-1-mRNA and p170 were detected. AS' and AP'were labelled by FITC and designated as ASF' and APF', respectively. In addition, the intracellular concentration of them was detected by FACS. RESULTS: AP' significantly enhanced the sensitivity of K562/AO2 to DOX, down-regulated the expression of mdr-1 and MRP-mRNA and p170, elevated the intracellular concentration of the two AOD, while AP had no effect. The uptake of APF' was significantly higher than that of ASF' in K562/AO2, and the fluorescence was observed in the plasma and nuclear of K562/AO2 cells. CONCLUSION: (AOD targeting mdr-1 promoted the drug sensitivity of drug-resistant tumor cells. 2 AOD had no cytotoxicity to tumor cells. 5 Low molecule PEG enhanced significantly the uptake of AOD by tumor cells.

ATP Binding Cassette Transporter, Subfamily B, Mem↗