Search PubMed⌕ Search

Biomedical subjects

Zhen Wang

Publications and source records attributed to Zhen Wang.

At least 91 records · Page 5Linked to original sources
PubMed2004

[Fabrication of custom-made artificial semi-knee joint based on rapid prototyping technique: three-dimensional reconstruction of femoral condyle].

OBJECTIVE: To achieve three-dimensional (3D) contour image of bone and articular cartilage for fabricating custom-made artificial semi-knee joint as segment bone allograft. METHODS: The distal femora of human and pig were scanned with Picker 6000 spiral X-ray computed tomography with 1.0 mm thick slice. The data obtained were treated in Voxel Q image workstation for 3D reconstruction with volume rendering technique. After being downloaded to personal computer at 0.1 mm interval, the transaxial 2D image data were converted into 2D digitized contour data by using image processing software developed by the team. The 2D digitized data were inputted into image processing software of Surfacer 9.0 (Imageware Company, USA), then the 3D wire frame and solid images of femoral condyle were reconstructed. Subsequently, based on the clinical experience and the requirement of the design of artificial knee joint, the 3D contour image of bone or articular cartilage was extracted from the surrounding. RESULTS: The 3D contour image of bone or articular cartilage presented was edited and processed easily for the computer aided design (CAD) of custom-made artificial knee joint. CONCLUSION: The 3D contour image of bone and articular cartilage can be obtained by spiral CT scanning, and the digitized data can be applied directly to CAD of custom-made artificial joint and subsequently rapid prototyping fabricating. In addition, the reconstruction method is simple and can be applied widely to clinical implant fabricating practice of dentistry and orthopaedics.

Adult↗
PubMed2004

[Cloning of human angiogenesis inhibitor METH1 and its expression in mammalian cells].

OBJECTIVE: To get the full length of human METH1 cDNA and express it steadily in mammalian cell stably. METHODS: METH1 was amplified by RT-PCR, and cloned into pCDNA3.0 after confirmed by sequence analysis. HepG2 cells were transfected by Lipofectamine reagent and then selected in medium with G418. The expression level of METH1 was detected by RT-PCR and Western blot. RESULTS: METH1 with expected length was effectively amplified, and completely matched the published sequence of encoding mature peptide [GI:5725505] as shown by sequence analysis. Eukaryotic vector expressing METH1 was obtained by gene cloning, cells expressing METH1 was got by selection with G418 at 3 weeks after transfection. RT-PCR and Western blot showed high level expression of METH1. CONCLUSION: Full length of human METH1 gene is cloned successfully and expressed in HepG2 steadily, The results set up a basis for the study of effects of METH1 on hypertrophic scar angiogenesis.

ADAM Proteins↗
PubMed2004

[Fabrication of custom-made artificial semi-knee joint based on rapid prototyping technique: computer-assisted design and manufacturing].

OBJECTIVE: To design a new custom-made artificial semi-knee joint based on rapid prototyping(RP) technique and to explore a method to solve necroses of allocartilage in hemi-joint allotransplantation. METHODS: Based on the extracted 3D contour image of the articular cartilage of femoral condyle, the custom-made artificial semi-knee joint was designed with Surfacer 9.0 image processing software. The artificial semi-knee joint design used the femoral condylar 3D contour of the patient as the outer face and the subchondral bone 3D contour of allograft bone as inner face. One dado for medullary nail and two for special designing cages which were used to fix the cartilage into the allograft were added on the inner face. After being converted into RP data format, the computer-assisted design was imported into the LPS600 rapid prototyping machine, and the prototype was achieved. Furthermore, the prototype could be modified by hand according to the design. Then the RP model was used as a positive mould to build up a silica gel negative mould, and the negative mould was sent to the factory to manufacture Ti-6A1-4V alloy articular cartilage through ordinary mould-melted founding process. Finally, the whole metal cartilage was completed after melting two special cages on it and polishing it. RESULTS: A new custom-made artificial semi-knee joint was made and used to treat a 14-year old patient. The custom-made artificial semi-knee joint and the subchondral bone were a perfect match. The operative result was satisfactory. The patient could walk 5 weeks after operation. The bone healing of the auto-bone and allo-bone was achieved 6 months later. A follow-up period lasting 1 year showed that the knee joint played a good function. CONCLUSION: The artificial semi-knee joint is a good match for the allograft bone and a good idea to solve necroses of allocartilage in hemi-joint allotransplantation.

Adolescent↗
PubMed2004

[Clinical analysis of 7 cases of adult prostate sarcoma].

OBJECTIVE: To investigate the diagnosis, treatment and prognosis of adult prostatic sarcoma. METHODS: The records of 7 patients with prostate sarcoma were reviewed in the light of clinical manifestation, laboratory examination, therapeutic methods and histological subtypes. Several clinicopathological variables were assessed for prognostic significance. RESULTS: Of the 7 cases, 3 were leiomyosarcoma, 3 rhabdomyosarcoma and the other malignant neurilemoma. Most patients presented urinary obstruction, and the diagnosis of prostate sarcoma was established with ultrasound guided biopsy. Histological subtypes were related to the rate of survival. Two patients received radical cystoprostatectomy and died 13 and 21 months respectively after operation. Two cases underwent total pelvic exenteration, followed by chemotherapy and/or radiotherapy and still alive 15 months after operation. The other 3 received only chemotherapy and/or radiotherapy and died 7 months on average after diagnosis. CONCLUSION: The long-term survival rate for adults with prostate sarcoma is low. Early diagnosis and complete surgical resection offer patients the best chance for survival. Long-term surveillance is necessary for the early detection of recurrence.

Adult↗
PubMed2004

[The relationship between serum calcitonin gene-related peptide, sex hormone, homocysteine and coronary artery disease in postmenopausal women].

OBJECTIVE: To investigate the relationship between serum calcitonin gene-related peptide (CGRP), homocysteine (Hcy), sex hormone, and coronary heart disease (CHD) in postmenopausal women. METHODS: In a cross-sectional study, serum CGRP, estradiol (E(2)), progesterone (P) and Hcy levels of 144 postmenopausal women undergoing diagnostic CHD (75 with CHD and 69 without CHD) and 66 healthy young women were measured. RESULTS: The occurrence of CHD was correlated with high Hcy level and low CGRP level. The mean serum CGRP level was significantly lower in CHD postmenopausal women than in without CHD ones [(103.6 +/- 59.8) ng/L vs (164.6 +/- 50.7) ng/L, P < 0.01]. The mean serum E(2) level was significantly lower in CHD postmenopausal women than in without CHD ones [(67.9 +/- 24.4) pmol/L vs (91.7 +/- 23.0) pmol/L, P < 0.01]. The mean serum P level was significantly lower in CHD than in without CHD postmenopausal women [(0.89 +/- 0.46) nmol/L vs (1.11 +/- 0.45) nmol/L, P < 0.01]. The mean serum Hcy level was significantly higher in CHD than in without CHD postmenopausal women [(15.3 +/- 6.5) micromol/L vs (10.2 +/- 2.8) micromol/L, P < 0.01]. By multivariate logistic regression, the OR of high Hcy level > or = 1, P < 0.01, that means Hcy is an independent risk factor of CHD. The OR of CGRP, E(2) and P were all < or = 1, indicating that they were independent protective factor. CONCLUSIONS: Hcy is an independent risk factor of CHD. CGRP, E(2) and P are independent protective factors of CHD. There was no relationship between Hcy, CGRP and E(2) and P.

Adult↗
PubMed2004

[Study on extraction technology for extract and flavonoids in Chrysanthemum morifolium by orthogonal design].

OBJECTIVE: To ascertain extraction technology condition for extract and flavonoids from Chrysanthum morifoliwn. METHOD: The optimizing ultrasonic extraction condition on the basis of extractive yield and flavonoids were determined by orthogonal design. RESULT: The order of factors which affected the flavonoid extraction was extraction times > ethanol concentration > ultrasonic time > solvent quantity. CONCLUSION: The optimum ultrasonic extractions are A2B3C3D3. Compared with traditional extraction, ultraction method is timesaving, simple to operate, stable and need not be heated.

Chrysanthemum↗
PubMed2004

[Study on ultrasonic extraction techniques of flavonoids in Chrysanthemum morifolium].

OBJECTIVE: To optimize the ultrasonic extraction condition for flavonoids from Chrysanthemum morifolium. METHOD: The extraction rate of flavonoids optimized condition (ethanol concentration, ultrasonic time, solvent quantity and extraction times) was determined by orthogonal design. UV-Spectrophotometry was used for the determination. RESULT: The order of factors to affect the flavonoid extraction was ethanol concentration > extraction times > solvent quantity > ultrasonic time. CONCLUSION: The optimum ultrasonic extractions were: A2 B2 C3 D3. Compared with traditional extraction, ultraction method can save time, be easy to operate, improve extraction rates and need no heating.

Chrysanthemum↗
PubMed2003

Three-dimensional structural location and molecular functional effects of missense SNPs in the T cell receptor Vbeta domain.

The mechanisms by which human single nucleotide polymorphisms (SNPs) influence susceptibility to disease are not yet well understood. In a previous study, we developed a structure-based model that may be used to identify which missense SNPs are neutral and which are deleterious to protein function and so potentially involved in disease (Wang and Moult, Hum Mutat 2001;263-270). The model has now been applied to a set of 54 missense cSNPs in the 46 functional T-cell receptor Vbeta-genes. Most of these missense cSNPs are found to be neutral, but 10 are identified as likely deleterious to protein function. Only one was previously associated with disease. We suggest that the others may be disease related but that redundancy in the T-cell response prevents any simple, monogenic effect. Therefore, these SNPs are the most likely contributors to complex, polygenic disease traits. It has been noted that there is a surprisingly high (74%) fraction of nonsynonymous SNPs in these genes. Contrary to expectation, the analysis shows that these are not associated with an unusually high fraction of deleterious SNPs, nor do they significantly contribute to a larger range of antigen recognition or a reduced superantigen-binding repertoire.

Binding Sites↗
PubMed2003

Modulation of glucocorticoid receptor transcriptional activation, phosphorylation, and growth inhibition by p27Kip1.

The cyclin-dependent kinase inhibitor p27Kip1 is frequently inactivated in human cancers. Glucocorticoids, acting through the glucocorticoid receptor (GR), are frequently used to treat certain malignancies and are growth inhibitive, but the relationship between GR activity and p27 status has not been explored. We have therefore examined GR-dependent transcriptional activation, receptor phosphorylation, and glucocorticoid-dependent growth inhibition in p27-deficient (p27-/-) murine embryonic fibroblasts (MEFs). We find that GR transcriptional enhancement as well as receptor phosphorylation at two putative cyclin-dependent kinase sites are elevated in p27-/- MEFs, relative to control cells. This increased GR transcriptional activation appears to be mediated through the GR N terminus, and coexpression of the GR N-terminal coactivator, DRIP150, further enhanced GR-dependent transcriptional activation. Furthermore, p27-/- MEFs are partially resistant to the growth inhibitory effects of glucocorticoids. Thus, p27 appears to be an important element in the GR transcription and growth inhibitory responses.

Animals↗
PubMed2003

Endothelial cell diversity revealed by global expression profiling.

The vascular system is locally specialized to accommodate widely varying blood flow and pressure and the distinct needs of individual tissues. The endothelial cells (ECs) that line the lumens of blood and lymphatic vessels play an integral role in the regional specialization of vascular structure and physiology. However, our understanding of EC diversity is limited. To explore EC specialization on a global scale, we used DNA microarrays to determine the expression profile of 53 cultured ECs. We found that ECs from different blood vessels and microvascular ECs from different tissues have distinct and characteristic gene expression profiles. Pervasive differences in gene expression patterns distinguish the ECs of large vessels from microvascular ECs. We identified groups of genes characteristic of arterial and venous endothelium. Hey2, the human homologue of the zebrafish gene gridlock, was selectively expressed in arterial ECs and induced the expression of several arterial-specific genes. Several genes critical in the establishment of left/right asymmetry were expressed preferentially in venous ECs, suggesting coordination between vascular differentiation and body plan development. Tissue-specific expression patterns in different tissue microvascular ECs suggest they are distinct differentiated cell types that play roles in the local physiology of their respective organs and tissues.

Cells, Cultured↗
PubMed2003

Non-caspase-mediated apoptosis contributes to the potent cytotoxicity of the enediyne antibiotic lidamycin toward human tumor cells.

Enediyne antibiotics have been reported to be the most potent cytotoxic antitumor agents. The pathway by which these compounds cleave DNA and induce apoptosis of tumor cells may be different from the caspase-mediated pathways that initiate typical apoptosis. In this report, we studied the apoptosis induced by lidamycin (LDM), a member of the enediyne antibiotic family, and compared the characteristics of LDM-induced apoptosis with those of typical apoptosis induced by mitomycin C or etoposide. Chromatin condensation occurred very rapidly and appeared as speckles in human hepatoma BEL-7402 and breast carcinoma MCF-7 cells after treatment with 1 microM LDM. In addition, co-staining the cells with the mitochondria-specific dye Mitosensor and the DNA-specific dye Hoechst 33342 enabled the visualization of mitochondria in normal control and LDM-treated cells but not in mitomycin C-treated cells. Neither the caspase inhibitor VAD-fmk nor the caspase-3 inhibitor DEVD-fmk was able to inhibit the DNA ladder patterns caused by LDM in BEL-7042 or MCF-7 cells. Smaller fragments of histone H1 cleaved by LDM were detected by SDS-PAGE, indicating that the site of LDM action is the internucleosomal structure. Although caspase-9, caspase-3/7, and caspase-6 activities were increased in BEL-7402 cells, and caspase-7 activity was increased in MCF-7 cells after treatment with 1 microM LDM, this occurred much later, indicating that chromatin condensation reached the maximal level rapidly while caspase activities still remained low. Taken together, these results demonstrate that LDM induced rapid DNA cleavage and chromatin condensation independently of caspase activities; this may contribute to its highly potent cytotoxicity toward tumor cells.

Aminoglycosides↗
PubMed2003

p38 Inhibitors: piperidine- and 4-aminopiperidine-substituted naphthyridinones, quinolinones, and dihydroquinazolinones.

We have synthesized a series of C7-piperidine- and 4-aminopiperidine-substituted naphthyridinones, quinolinones, and dihydroquinazolinones that are highly potent inhibitors of both p38MAP kinase activity and TNF-alpha release. The 4-aminopentamethylpiperidine naphthyridinone 5, which was designed to block metabolism at major 'hot spots', combined excellent inhibitory potency with good oral bioavailability in the rat.

Animals↗
PubMed2003

Design and synthesis of potent, orally bioavailable dihydroquinazolinone inhibitors of p38 MAP kinase.

The development of potent, orally bioavailable (in rat) and selective dihydroquinazolinone inhibitors of p38alpha MAP kinase is described. These analogues are hybrids of a pyridinylimidazole p38alpha inhibitor reported by Merck Research Laboratories and VX-745. Optimization of the C-5 phenyl and the C-7 piperidinyl substituents led to the identification of 15i which gave excellent suppression of TNF-alpha production in LPS-stimulated whole blood (IC(50)=10nM) and good oral exposure in rats (F=68%, AUCn PO=0.58 microM h).

Animals↗
PubMed2003

Microsurgical treatment of Mooren's corneal ulcer.

This study evaluated the effect of microsurgery of lamellar keratoplasty (LKP) on Mooren's corneal ulcer. The surgical effect, postoperative astigmatism, postoperative vision, postoperative ulcer recurrence, and surgical complications of 2 groups of consecutive Mooren's ulcer inpatients treated respectively by non-microsurgery of LKP and microsurgery of LKP were analyzed. There were significant differences of the effect, postoperative astigmatism, postoperative vision, postoperative ulcer recurrence, and surgical complications between the 2 groups. The effect and postoperative vision of the microsurgery-treated group were better than those of the non-microsurgery-treated group. The postoperative astigmatism, postoperative ulcer recurrence, and surgical complications of the microsurgery-treated group were less than those of the non-microsurgery-treated group. Microsurgery of LKP of Mooren's corneal ulcer can greatly improve the cure rate of the disease and postoperative vision, and reduce surgical complication and postoperative ulcer recurrence.

Adolescent↗
PubMed2003

The unanticipated loss of SO2 from sulfonamides in collision-induced dissociation.

A potent and selective sulfonamide beta3 agonist with an excellent pharmacokinetic profile has recently been synthesized. During the analysis by liquid chromatography/tandem mass spectrometry (LC/MS/MS) of metabolites of the sulfonamide N-[4-[2-(2-hydroxy-2-pyridin-3-ylethylamino)ethyl]phenyl]-4-[4-(4-trifluoromethylphenyl)thiazol-2-yl]benzulfonamide (compound A), we observed loss of 64 Da for a few of the metabolites in the negative ion mode. Accurate mass measurements performed with Fourier transform ion cyclotron resonance (FTICR) mass spectrometry and quadrupole time-of-flight (Q-TOF) mass spectrometry suggested that the loss of 64 Da corresponded to the loss of SO(2). The same phenomenon was observed for a group of structurally related and commercially available compounds that also contain a sulfonamide moiety. MS/MS analysis of the fragment ions that had lost SO(2) in the ion source suggested that these ions were covalently bound rather than ion-molecule complexes. The neutral loss involving the cleavage of two bonds was unanticipated and suggested a complex rearrangement process. A mechanism for the loss of SO(2) has been proposed.

Animals↗
PubMed2003

Mechanism of three inhibitors of TACE in blocking the converting of pro-TNF alpha into sTNF alpha.

The effects of inhibitors of TNF alpha converting enzyme (TACE) on TNF alpha secretion were studied to develop an approach to interfere inflammation processes. The HL-60 cell lines were stimulated in vitro with LPS intravenously for different time to establish the cellular model of inflammation and simultaneously induce in vivo inflammation animal model by LPS The cytotoxic effects of soluble TNF alpha were checked using MTT colorimetric method to determine the rate of cell proliferation. The level of expression of TACE was detected by using RT-PCR, FCM and immuno-histochemical technique respectively. It was found Chinese medicine Reduqing (RDQ) could inhibit the transcription of TNF alpha mRNA induced by LPS stimulation (P < 0.01, compared with the control). The antioligodeoxyribonucleotide (anti-ODN) of TNF alpha mRNA could inhibit 78.9% of TNF alpha secretion. The mimic peptides of TACE substrates with hydroxamine group showed potency in vivo and in vitro against converting of pro-TNF alpha. It was concluded that all the three types of TACE inhibitors can regulate the expression of TACE at different levels and inhibit sTNF alpha secretion, indicating TACE is a novel target for inflammation therapy.

ADAM Proteins↗
PubMed2003

[Immunological research of rat osteoblast xenotransplantation].

OBJECTIVE: To detect the immunoreaction after osteoblast xenotransplantation and to investigate the possibility of heterogenic osteocyte transplantation and tissue engineered bone reconstruction. METHODS: Rat osteoblasts were isolated by two-part bony digestion/elements in culturing, and incubated in vitro at 37 degrees C, 5% carbon dioxide for 5 days until they multiplied and formed a monolayer on the bottom of dish. Twenty-eight rabbits were divided into 3 groups. Autograft of osteoblasts(group A), xenograft of osteoblasts(group B) and normal saline(group C) were implanted into the rectus abdominus muscle. The immunological and histological observations were performed after 1, 2, 4 and 8 weeks of transplantation. RESULTS: Cultured cells reached confluence within 5 days and was identified as osteoblasts by ALP staining and Bon kossa staining. The result of host versus graft reaction was negative. In group B, specific antibody reaction was detected 2 weeks and 4 weeks after transplantation. Cell mediated cytotoxicity was detected after 2 weeks, reached the peak value 4 weeks later, and then began to decline 8 weeks later. HE staining showed mass inflammatory cells and no ectopic ossification after 8 weeks. CONCLUSION: Heterogenic osteoblast transplantation will lead to an obvious change in host humoral and cellular immunity and lost the ability of bone formation. So, it can not be used for the reliable cell sources for osteocyte transplantation or tissue-engineering bone reconstruction.

Animals↗