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Biomedical subjects

Yan Wang

Publications and source records attributed to Yan Wang.

At least 505 records · Page 28Linked to original sources

[What the Prorocentrum species should be?--a review on identification of a Prorocentrum species from the East China Sea].

In the past decade, the Prorocentrum bloom was the most frequently occurred bloom in the East China Sea. It occurred every one year or two years, and covered huge areas. There were arguments on the identification of Prorocentrum bloom causative species. Some scientists thought the species being P. dentatum Stein, but the others thought that it was a new species, P. donghaiense Lu. For achieving the proper classification of the species, an "International Workshop on HAB Causative Species--Taxonomic View on a species of Prorocentrum in the East China Sea" was held in Shenzhen, China in November, 2002. By reviewing as much as available references, and by comparing the Prorocentrum specimen from the East China Sea with those from Japan, Korea and USA, scientists participated in this Workshop agreed that: 1) the specimens from Japanese and Korean waters, and from CCMP, USA were the same species; 2) the features of anterior projection and cell surface marking were similar to those of originally described P. dentatum Stein; 3) the major difference is the cell size. The specimens from the East China Sea were mostly less than 20 microns long, whereas the size of the original described P. deatatum was larger than 50 microns; 4) the minor difference is the shape of the cell end. The original described P. deatatum was with a pointed end, whereas the cells from the East China Sea were mostly with a rounded end. There was no final agreement for the species identification at the Workshop. By summing all views of scientists from the Workshop, the authors suggested that the bloom causative species of Prorocentrum in the East China Sea, as well as so-called species of P. dentatum from other East Asian waters, should be the same species. They are all P. donghaiense Lu.

China↗

Allolymphocyte apoptosis induced by soluble liver specific antigen.

OBJECTIVE: To investigate the alloimmunogenicity of liver specific antigen and its effects on allolymphocytes. METHODS: Liver specific antigen isolated from inbred F344 rats was used as immunogen to immunize inbred Lew rats through different immunization pathways such as low-dose long-term hind footpad, high-dose portal vein and thymus immunization. Western blotting, DNA fragments gel electrophoresis, mixed lymphocyte culture (MLC) and mixed lymphocyte hepatocyte culture (MLHC) were employed to analyze the immune state after immunization. RESULTS: At the time point of sampling, different degree of specific low immunoresponses appeared in all immunized groups as well as cyclophosphamide (CY) treated group. Compared with group I, other groups expressed caspase-3 significantly as detected by using Western blotting. DNA fragment gel electrophoresis of splenocytes showed lymphocyte apoptosis. Compared with the group I, MLC of the experimental groups showed no significant changes except that of the group V, whereas MLHC decreased markedly (P<0.05). CONCLUSIONS: Liver specific antigen not only has alloimmunogenicity to induce alloimmunoreaction but induce antigen specific low immunoresponses and antigen specific lymphocyte apoptosis by high-dose or low-dose long-term immunization. It may be an important transplantation antigen that may lead to a novel way to liver transplantation immunotolerance.

Animals↗

[Clinical significance of the parameters of prostate volume measured by TRUS in evaluating bladder outlet obstruction].

OBJECTIVES: To explore the parameters of prostate volume measured by TRUS in diagnosing bladder outlet obstruction (BOO) from BPH. METHODS: Prostate volume(PV), transition zone volume(TZV) and transition zone index (TZI) were measured with TRUS in 116 cases of BPH aged from 59-75. Urodynamics were conducted, including Qmax, Pdet. Qmax and AG value. The correlation analysis was performed among them. RESULTS: PV, TZV and TZI were (69.7 +/- 45.9) ml, (43.5 +/- 25.6) ml and 0.57 +/- 0.14, respectively. Qmax, Pdet. Qmax and AG were (8.31 +/- 5.12) ml/s, (82.34 +/- 33.47) cm H2O and 66.72 +/- 30.46, respectively. IPSS and PSA were 25.3 +/- 4.7 and (4.12 +/- 3.64) ng/ml, respectively. The correlation analysis showed TZI (r = 0.742, P = 0.017) and TZV (r = 0.674, P = 0.031) were positively correlated with AG value. IPSS was positively correlated with TZV and TZI. There was also a positive correlation between PSA and PV, TZV and TZI. CONCLUSIONS: As urodynamics, the parameters of prostate volume measured by TRUS are reliable to diagnose BOO due to BPH.

Aged↗

[Pathological study on the deep scleral flap and external trabecular membrane obtained from non-penetrating trabecular surgery].

OBJECTIVE: To study the anatomic background of non-penetrating trabecular surgery (NPTS) and to explore the resistant site of aqueous outflow in primary open-angle glaucoma. METHODS: NPTS was performed in 18 eyes of 12 cases (10 males, 2 females) with POAG. The age of these patients ranged from 42 to 65 years old. The deep scleral flap and external trabecular membrane were obtained during the surgical procedure and were examined by light microscope, scanning electron microscope (SEM) and transmission electron microscope (TEM). RESULTS: The beginning part of the collection canal in the outer wall of the Schlemm's canal were very narrow, and there was electron dense material (so-called plaques) around the outer wall of the Schlemm's canal. The external trabecular membrane consisted of adjacent trabecular meshwork and part of the corneoscleral trabecular meshwork. The number of the trabecular cells was decreased and a large amount of electron dense materials were deposited in the adjacent trabecular meshwork. The holes of the corneoscleral trabecular meshwork was small and irregular. In the corneoscleral trabecular meshwork, the trabecular lamellae was thicken, the amount of elastic-like fibers was increased and the trabecular cells, especially the nucleus, were enlarged. In the advanced stage of POAG, a great amount of electron dense material was deposited in the corneoscleral trabecular meshwork and the inter-trabecular spaces was blocked. CONCLUSIONS: The deep scleral flap of NPTS contains the outer wall of Schlemm's canal and the external trabecular membrane, which consists of the inner wall of the Schlemm's canal, the adjacent trabecular meshwork and part of the corneoscleral trabecular meshwork. The main resistant site of aqueous outflow in POAG lies in the adjacent trabecular meshwork and in part of the corneoscleral trabecular meshwork. The outer wall of the Schlemm's canal is another important resistant site for aqueous outflow.

Adult↗

[Biochemical pharmacological effects of lurongjing on young or old mice].

OBJECTIVE: To investigate the effect of Lurongjing (LRJ) on young or old mice. METHODS: In vivo monoamine oxidase (MAO) and superoxide dismutase(SOD) activities, the contents of monoamines(5-HT, NE, DA), malondialdehyde (MDA), RNA and protein, and the incorporations of [3H] Uridine into RNA and [3H] Leucine into protein in liver tissue were measured. RESULTS: The inhibition of MAO-B activity and the increase of monoamines(5-HT, DA) level, the increase of RNA and protein level, and the incorporations of [3H] Uridine into RNA and [3H] Leucine into protein in liver tissue, the enhancement of SOD activity and the decrease of MDA content in brain and liver tissues were selectively observed in old mice(24 months) than in young mice(1 month) by LRJ (i.g., 4.0 g/kg) administrated orally for 10 successive days. CONCLUSION: LRJ exhibits some anti-aging effect in old mice.

Aging↗

[Comparison of synthesizing Collagen I and III in periodontal ligament cells and gingival fibroblasts].

OBJECTIVE: To investigate the different characteristics of periodontal ligament cells and gingival fibroblasts in synthesizing Collagen I and III. METHODS: Periodontal ligament cells and gingival fibroblasts were cultured from the same patient and detected for expression of Collagen I and III by immunocytochemical methods. RESULTS: The immunocytochemical staining showed Collagen I and III were positive in periodontal ligament cells, and mild positive in gingival fibroblasts. Statistical analysis suggested the difference between gingival fibroblasts and periodontal ligament cells. CONCLUSION: There were differences between the periodontal ligament cells and gingival fibroblasts in synthesizing or secreting of Collagen matrix.

Cells, Cultured↗

[Clinical evaluation of tunnel-restoration].

OBJECTIVE: To evaluate the clinical effect of tunnel-restoration. METHODS: 35 teeth with pulpitis or periapical periodontitis caused by interproximal caries were selected. Tunnel-restoration was used after endodontic treatment. Clinical examinations were taken to follow up all the teeth at one year and two years respectively after treatment. RESULTS: At one year after treatment, 35 cases were followed up, the rate of success was 100%. At two years after treatment, 33 cases were followed up and 2 cases were lost, the rate of success was also 100%. CONCLUSIONS: Proximal contact point and marginal ridge of the teeth were preserved by using tunnel-restoration, which is very important to restore proximal contact, enhance the ability of resistance to fracture, and has good clinical effect.

Dental Restoration, Permanent↗

[Change of circulating TNF-alpha in patients with advanced periodontitis before and after periodontal initial therapy].

OBJECTIVE: To investigate the effect of periodontal initial therapy on circulating tumor necrosis factor-alpha (TNF-alpha) in patients with periodontitis. METHODS: Patients with advanced periodontitis were selected. Sulcus bleeding index (SBI), probing depth (PD), and circulating TNF-alpha concentration were assessed respectively before and 4-6 weeks after periodontal initial therapy. RESULTS: The level of circulating TNF-alpha in patients with periodontitis was significantly higher than that in healthy control subjects (P < 0.01). After periodontal initial therapy, SBI, PD and circulating TNF-alpha concentration were reduced significantly (P < 0.01) in patients with periodontitis. CONCLUSION: Periodontitis may have profound effects on systemic health through the elevation of circulating TNF-alpha. Prevention and treatment of periodontitis should be important in maintaining systemic health.

Adult↗

[The effect of periodontal initial therapy on circulating TNF-alpha and HbA1C in type 2 diabetes patients with periodontitis].

OBJECTIVE: To investigate the effect and mechanism of periodontal initial therapy on type 2 diabetes patients with periodontitis. METHODS: 15 type 2 diabetes patients with periodontitis were selected. Their body mass index (BMI), sulcus bleeding index (SBI), probing depth (PD), circulating tumor necrosis factor-alpha (TNF-alpha) concentration, and the value of glycosylated hemoglobin (HbA1C), triglycerides (TG) and cholesterol (CHOL) were assessed respectively before and 4-6 weeks after periodontal initial therapy. RESULTS: After initial therapy, SBI, PD, circulating TNF-alpha concentration, and the value of HbA1C and TG were reduced significantly (P<0.05), while there were no significant differences in BMI and CHOL value (P>0.05). CONCLUSIONS: Periodontal initial therapy can effectively reduce HbA1C value in type 2 diabetes patients with periodontitis, possibly through the reduction of circulating TNF-alpha concentration.

Adult↗

[Distribution of cerebral vascular hemodynamic indexes].

OBJECTIVE: To describe the distribution of cerebral vascular hemodynamic indexes (CVHI). METHODS: A number of 25,355 age 35 and over were selected in the Northeast China by cluster sampling. CVHI were checked during baseline survey and were followed to see the occurrence of stroke. Distribution of CVHI among non-stroke population, individuals prior to the onset of stroke and patients with stroke were described. RESULTS: The CVHI accumulative score, V(mean), V(max) and V(min) were dramatically decreasing, but RV, Zcv, WV and DR were significantly increasing as age increased. V(max), RV and CP were significantly higher in males but WV was lower than that of females. The CVHI accumulative score, V(min) and RV were 95.0, 10.23 and 75.8 in non-stroke population, 51.25, 6.71 and 122.72 pre stroke group, and 55.0, 6.78 and 115.89 in patients with stroke respectively. There were significant differences among three groups after controlling of age and sex (P < 0.01). CONCLUSION: Variance of CVHI was closely related to age, and there appeared a significant abnormal of CVHI before and after stroke.

Age Factors↗

[Impact of lead pollution in environment on children's health in Shenyang City].

In this thesis, based on field sampling and indoor integrated analysis with GIS technology, the impact of lead pollution in the atmosphere, dust, soil on the children was explored systemically. Results showed that, Lead exposure in environment was widely distributed and Lead pollution was serious in Shenyang city. The spatial variations of Lead, with four high content centers in the soil, dust and atmosphere, were distinct in all the environmental media. Moreover, there were daily, seasonal and annual variations in the atmosphere. The impact of lead pollution in environment on children health was serious in Shenyang city. The blood lead content of the children (ZPP > 2.3 mumol/L) with the age of 0-10 ranged from 10.98 to 511.2 micrograms/L, and the average of 135.59 micrograms/L. The blood content of 40% children was beyond the normal standard. And correlative degree of lead contents between in blood and in atmosphere was highest, secondly in soil, and last in dust. With the implication of non-lead gasoline the lead content in the atmosphere had declined greatly. Along with the flying dust, the lead in the soil and dust was likely to entering into the atmosphere to bring out potential pollution risk.

Child↗

[The reconstruction of three-dimension morphology of proximal femur].

OBJECTIVES: To reconstruct the morphology of the proximal femur and measure the parameters of them by means of the computer-aided design (CAD) in order to provide help to the design and research of the domestic prosthesis, event for the selection of the adapted implant for the doctors before operation. METHODS: The data of 160 healthy Chinese proximal femur images were obtained by the PHLLIP SR7000 computer tomography. The correlative parameters were measured exactly by medical imaging software. Then the imaging data were input into an computerized contouring program which generates the three dimensional coordinates representing periosteal and endosteal contours of the femur for each CT slice. Though the computer-aided design (CAD) software, the three-dimensional solid model was reconstructed by the vectorisation of image contours. In the circumstance of CAD system, the bone axis is defined as the line across the geometric center of the cross-section of the isthmus and 20 mm above the lesser trochanter mid-point. We measured the parameters of the endosteal and periosteal dimensions of the medullary canal. RESULTS: The parameters of the medullary canal measured with the reconstructed normal Chinese femur have significant difference from that measured with the Caucasian's. The extracortical and endosteal parameters of male have significant differences from most of female's. However, there were no significant differences in endosteal width between different age groups in two gender groups. From the proximal to the distal femur, the intersection angles between the longest mediolateral endosteal diameters of the slices and the plane of the femoral neck were increased. CONCLUSIONS: The reconstructive femur contains more information and can be cut at arbitrary levels which means it is facility to the research of the Morphology of the Proximal femur and the measurement of relative parameters. It is necessary to design the prosthesis which fit anatomic parameters of the Chinese femur. It needs to further study whether the gender factor will be considered in the prosthesis design. The angle between the anteversion and the helitorsion at the level 20 mm above the lesser trochanter midpoint should be noticed by the implant designers and doctors.

Aged↗

[Solid phase microextraction and derivatization of sulfide in blood with pentafluorobenzylbromide].

Solid phase microextraction (SPME) and derivatization with pentafluorobenzylbromide for sulfide in blood was presented in the paper. The derivative of sulfide was extracted for 20 min at the condition of room temperature by a polydimethylsiloxane fiber. 1,3,5-tribromobenzene (IS) was used as an internal standerd. GC/MS was used for analysis. The ions at m/z 394 (derivative of sulfide) and m/z 312 (IS) in the selected ion minitoring chromatograms were selected for quantitation. The compound was detectable at least 0.01 microgram/ml. By the determination in poisoning blood, this method would be demonstrated to be simple.

Benzene Derivatives↗

[Expression of ICAM-1 and VCAM-1 in human ameloblastoma and odontogenic keratocyst].

OBJECTIVE: To study the expression of ICAM-1 and VCAM-1 in human ameloblastoma (AB) and odontogenic keratocyst (OKC) and investigate the relation of ICAM-1 and VCAM-1 with the pathologic characteristic of AB and OKC. METHODS: The specimens of 38 cases of AB, 10 cases of OKC, 7 cases of normal oral mucosa (NOM) were examined by streptovidin-biotin method. Their expression was analyzed combining the pathologic characteristics. RESULTS: Comparing AB with OKC and NOM, there was a significant difference in ICAM-1 and VCAM-1 (P<0.05). The positive expression of ICAM-1 in AB was 65.2%, much higher than that in NOM(14.3%). There was no difference between the expression of ICAM-1 in OKC(60.0%) and in NOM. The positive vessels number stained by VCAM-1 in AB was significantly higher than that in OKC and NOM. The expression of ICAM-1 and VCAM-1 had no correlation to age, sex, histological types, lesion locations(P>0.05). CONCLUSION: ICAM-1 and VCAM-1 play an important role in genesis, development of AB and OKC and are related to cell differentiation and proliferation.

Adolescent↗

[Determination of puerarin, daidzin and daidzein in root of Pueraria lobata of different origin by HPLC].

OBJECTIVE: To develop an HPLC method to determine Puerarin, Daidzin and Daidzein in Pueraria lobata. METHOD: The separation was performed in a SYMMETRY C18 column with a mobile phase of methanol-1% HAC solution (gradient elution), the The detection wavelength being 250 nm. RESULT: The average recovery was respectively 101.7%, 100.7% and 101.7% (n = 3), RSD 0.43%, 0.82% and 1.50% (n = 3) for Puerarin, Daidzin and Daidzein. CONCLUSION: This method is suitable for the determination of Puerarin, Daidzin and Daidzein in Pueraria lobata and its preparation.

China↗

[Significantly improvement of antibody expression level in CHO cells through downregulation of the DHFR gene in expression vector].

AIM: To increase the expressed level of a human-mouse chimeric antibody against human bladder tumor in dihydrofolate reductase (DHFR) defective CHO cells(CHO/DHFR) via weakening the transcription of DHFR gene in the vector. METHODS: A series of chimeric antibody expression vectors with different deletions and mutations in the modulator sequence of DHFR gene were constructed to downregulate the DHFR gene expression. The vectors were used to transfect CHO/DHFR cells and the transfected cells were subjected to gene amplification in medium containing gradually increasing methotrexate (MTX). The expressed chimeric antibody was quantitated by ELISA. RESULTS: The downregulation of vector-produced DHFR gene introduced by mutation of the modulator sequence could significantly improve the gene amplification effect and the increased antibody production correlated to the reduction of DHFR gene expression. From the best group, a clone with antibody production of 55 microg/(10(6) cells.24 h) was obtained by subcloning. More than 100 microg/(10(6) cells.24 h) was achieved by zinic ion induction. CONCLUSION: MTX induced-increase of recombinant antibody production in CHO cells can be increased by weakening the expression of DHFR gene.

Animals↗