Biomedical subjects

J Fang

Publications and source records attributed to J Fang.

At least 91 records · Page 5Linked to original sources

PubMed2001

In vitro characterization of the metabolism of haloperidol using recombinant cytochrome p450 enzymes and human liver microsomes.

A systematic in vitro study was carried out to elucidate the enzymes responsible for the metabolism of haloperidol (HAL) using human liver microsomes and recombinant human cytochrome P450 isoenzymes. In the first series of experiments, recombinant cytochrome P450 (P450) isoenzymes were used to evaluate their catalytic involvement in the metabolic pathways of HAL. Recombinant CYP3A4, CYP3A5, and CYP1A1 were shown to be able to catalyze the metabolism of HAL to its pyridinium analog (HP(+)) and the oxidation of reduced HAL (RH) back to HAL; Recombinant CYP3A4, CYP3A5, CYP1A1, CYP2C19, CYP2C8, CYP2C9, and CYP2D6 were able to catalyze the dealkylation of HAL to 4-(4-chlorophenyl)-4-hydroxypiperidine (CPHP). CYP3A4 was capable of metabolizing HAL to its tetrahydropyridine analog 4-(4-chlorophenyl)-1-[4-(4-fluorophenyl)-4-oxobutyl]-1,2,3,6-tetrahydropyridine and metabolizing to CPHP; CYP3A4 and CYP3A5 were able to metabolize RH to its pyridinium analog (RHP(+)); CYP1A1, CYP1A2, and CYP3A4 were able to catalyze the oxidation of RHP(+) to HP(+). In the second series of experiments, the metabolic activities of human liver microsomes from 12 donors were correlated with catalytic activities of selective substrates of different P450 isoenzymes and immuno-reactivities toward different P450 isoenzymes. CYP3A4 activities were found to correlate to all the seven metabolic pathways of HAL mentioned above. This suggests a prominent role for CYP3A4 in the metabolism of HAL. Interestingly, it was found that recombinant CYP1A1 has the highest activity for oxidizing RHP(+) to HP(+). The activity of recombinant CYP1A1 was 50 times higher than CYP1A2 and 220 times higher than CYP3A4.

Antipsychotic Agents↗

PubMed2001

Dual function of human necrosis factor receptor 75 in cytotoxicity induced by human tumor necrosis factor alpha.

AIM: To study the function of human TNF receptor-75 (hTR75) and the interaction between human TNF receptor-55 (hTR55) and hTR75 in hTNFalpha-induced cytotoxicity. METHODS: HEp-2 cells were transfected with bicistronic expression vector of hTR75 gene, and HEp-2-A75 cells with intrinsic hTR55 and overexpressed hTR75 were obtained. Two hTNFalpha muteins with exclusive specificity for hTR55 or hTR75 were constructed, expressed in high-levels in E coli, and then purified. hTNFalpha-induced cytotoxicity was determined by crystal violet colorimetric method. RESULTS: The expression of hTR75 in HEp-2 cells was demonstrated by RT-PCR and indirect ELISA, and was quantified by binding of [125I]hTNFalpha and Scatchard analysis. The overexpressed hTR75 could markedly increase the susceptibility of HEp-2 cells to hTNFalpha. CONCLUSION: hTR75 could not only partially mediate hTNFalpha-induced cytotoxicity independently but also fulfill an accessory role in enhancing or synergizing hTR55-mediated cytotoxicity. It played a dual function in hTNFalpha-induced cytotoxicity in HEp-2 cells.

Antigens, CD↗

PubMed2001

[Allogeneic peripheral blood stem cell transplantation for 3 patients with beta-thalassemia major and 1 patient with congenital idiopathic haemolytic anemia].

OBJECTIVE: To examine the feasibility of allogeneic peripheral blood stem cell transplantation (Allo-PBSCT) for the hereditary haemolytic anemia (HHA). METHODS: Allo-PBSCTs were performed on 3 patients with beta-thalassemia major and 1 patient with congenital idiopathic haemolytic anemia by the HLA-identical siblings' donors or 1 locus-mismatch parent. The harvested stem cell contained nucleated cells (4.7-14.4) X 10(8)/kg recipient weight, CD(34) (+) CD(38)(-) cells(4.8-32.9) X 10(6)/kg and colony-forming-unit-granulocyte-macrophages (CFU-GM)(3.22-9.8) X 10(5)/kg. The conditioning regimen consisted of busulfan, cyclophosphamide, melphalan, thiotepa, fludarabine and antithymocyte globulin (ATG). RESULTS: All patients were engrafted and accomplished with the acute graft-versus-host disease (aGVHD). A patient had the controlled chronic GVHD. Three patients are survivals with ex-anemia; their Hb levels have been maintaining normality without transfusion. One died of the hepatic veno-occlusive disease. CONCLUSION: Allo-PBSCT is an effective and a new way to treat beta-thalassemia major and congenital idiopathic haemolytic anemia.

Anemia, Hemolytic, Congenital↗

PubMed2001

[Sentinel lymph node biopsy in head and neck cancer patients].

OBJECTIVE: By performing sentinel lymph node (SLN) biopsy, its detecting and predictive value to the cervical metastasis in the head and neck cancer patients was studied. METHODS: Intraoperative SLN biopsy was done in 51 untreated head and neck cancer patients who all had no metastasis before operation. The lesions were: laryngeal cancer 23, pharyngeal cancer 6, thyroid cancer 20 and cancer of the tongue 2. Fifteen minutes before taking the SLN, local 0.2 to 0.5 ml 2% isosulfan blue dye was submucously injected 0.5 cm away from the upper, lower, right and left margin of the primary tumor. The frozen sections of SLN were compared with the routine pathological sections of the cervical lymph nodes. The metastatic relation between the SLN and the cervical nodes as well as SLN's predictive value to the cervical nodes metastasis were analyzed. RESULTS: SLN was successfully revealed in 48 (94%) of these 51 patients, averaging 2.5 nodes per patient. They were: laryngeal cancer 22, pharyngeal cancer 6, thyroid cancer 18 and lingual cancer 1. Eleven of these SLNs were positive, among whom two had lymph node metastasis in addition to the SLN. Two others were false negative. The positive predictive value of SLNs to the cervical lymph node metastasis was 85%. CONCLUSION: The predictive value of sentinel lymph node to the cervical metastasis is important in head and neck cancer patients.

Adult↗

PubMed2001

[The status quo survey of false and inferior species in Chinese medicinal materials market in Hubei Province].

By taking a sample, unqualified varieties were investigated found in Chinese medicinal material examinatorial work near twenty years of six regional level and three countrylish level institutes for drug control and one comprehensive level-three grade-A hospital. By mail, false and inferior species and their origin of Chinese medicinal material were investigated found by sixteen institutes for drug control near ten years in Hubei province. 539 kinds of adulterants (750 cases) including 24 toxic species were found in above-mentioned investigations. Fales and inferior species are rampant in minority regions, which threatens people's health severely. It is urgent for supervising department to gorem the condition strictly.

Drugs, Chinese Herbal↗

PubMed2001

[Preparation and characteristics of human adherent natural killer cells induced by rhIL-15].

OBJECTIVE: This work was to do preliminary study on the characteristics and preparation of rhIL-15 induced adherent human natural killer cells (A-NK). METHODS: Natural killer cells (NK cells) were first separated by centrifugation on Ficoll-Hypaque gradients, plastic adherence and nylon wool column adherence. Then, they were further purified by Percoll discontinuous density gradient centrifugation and T cell panning. Fluorescence-activated cell scan (FACScan) was applied to evaluate the natural killer cells and assess their degree of purification. Then, the purified NKs were incubated in the presence of rhIL-2 (6,000 U/ml) or rhIL-15 (6,000 U/ml) and changed into adherent NK cells. In the next step, the adherent kinetics, proliferation and cytotoxicity of A-NKs obtained by two different cytokines were analyzed by cell counting, MTT and reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The adherent percentage, cytotoxity and proliferation of A-NKs generated in rhIL-15 culture were higher than those in rhIL-2. CONCLUSION: IL-15 is a better stimulator than IL-2 to induce adherent natural killer cells.

Cell Adhesion↗

PubMed2001

[Stratified 'capture-recaptured' methodology in the estimation on the number of cancer incidence cases].

OBJECTIVE: To develop a new method in estimating the number of cancer incidence in Yuexiu district in Guangzhou. METHODS: Data of cancer incidence was collected through hospital records and death certificates to develop a stratified capture-recaptured model. Related procedures for the parameter estimation were given and implemented on SAS language. RESULTS: Estimated numbers of both male and female cancer incidence in Yuexiu district were 610 and 520 respectively. The estimated miss-reporting rates on both male and female cancer incidence from hospital records and death certificates were 8.5% and 5.4% respectively. CONCLUSION: The result of simulation studies showed that stratified "capture-recaptured" model proposed in this paper was reliable for the estimation of the number of cancer incidence cases.

Female↗

PubMed2001

[Umbilical cord blood transplantation (UCBT) in thalassemia children].

OBJECTIVE: To evaluate the efficacy of allo-UCBT in thalassemia children. METHODS: Five patients with beta-thalassemia major (genotypes were homozygote of beta41-42, beta654 and double heterozygosities of beta41-42/beta654, beta41-42/-28, beta654/-28, respectively) were treated by allo-UCBT. The median age was 3 year and ten month old (31/2 - 7 2/12). Four donor-recipient pairs were HLA-identical and one 1 locus mismatch. The patients received a median UCB nucleated cells (NC) of 5.5 x 10(7)/kg body weight [range (4.7 - 7.7) x 10(7)/kg] and CD(34)(+)CD(38)(-) cells 2.8 x 10(5)/kg [range (0.6 - 4.5) x 10(5)/kg] and CFU-GM 1.09 x 10(5)/kg [range (0.24 - 230.00) x 10(5)/kg]. The conditioning regimen consisted ofbusalphan 16 - 20 mg/kg, cyclophosphamide 180 - 200 mg/kg, horse antithymocyte globulin (ATG) 90 mg/kg or rabbit anti-lymphocyte globulin (ALG) 25 mg/kg and melphalan of 90 mg/m(2) was added to four cases. Cyclosporine A (CsA) alone was administered in 3 cases, and a combination of CsA and methotrexate in the other 2 cases. RESULTS: Four cases were engrafted, but one rejected and recurred thalassemia state at day 60 past UCBT. One case had autologous reconstitution. The reconstitutions were found in all patients with neutrophils 0.5 x 10(9)/L at day 19 (14 - 22), platelets > 20 x 10(9)/L at day 37 (21 - 63). Two cases developed grade I and II acute GVHD respectively. None developed chronic GVHD. Three patients survived disease-freely (survival with ex-thalassemia state). The median follow-up was 18 months, the probability of survival was 100%. CONCLUSION: Allo-UCBT could reconstitute hematopoiesis with low frequency and mild grade of GVHD. It is an effective treatment for thalassemia.

Child↗

PubMed2001

[Effect of liuwei dihuang decoction, on the cytokine expression in splenocytes in AA rats].

OBJECTIVE: The effect of Liuwei Dihuang decoction (LW) on the function of splenic T helper cells (Th) was studied and compared with those of the immune inhibitors such as cyclophosphamide (Cy) and cyclosporin A (CsA) in AA rats. METHODS: The expression of mRNA for IFN-gamma, IL-2, IL-4 and IL-10 in splenic T-Lymphocytes of adjuvant arthritis (AA) rats was evaluated using reverse transcription polymerase chain reaction (RT-PCR) technique. RESULTS: mRNA expression level of IL-2 had a tendency to elevate, but the mRNA expression levels of IFN-gamma, IL-4 and IL-10 were significantly decreased in AA rats in comparison with control groups. LW treatment significantly inhibited the mRNA expression of IL-2 and promoted the expression of IFN-gamma, IL-4 and IL-10 in splenocytes of AA rats, with an obvious characteristic as compared with that of Cy or CsA. CONCLUSION: LW can correct the indifferent balance of the functions of splenocyte Th1/Th2 in AA rats.

Animals↗

PubMed2001

[Clinical study of the sentinel lymph node of patients with laryngeal and hypopharyngeal carcinomas].

OBJECTIVE: To investigate the methods of detecting the sentinel lymph node of laryngeal and hypopharyngeal carcinomas and its predictive value in the cervical metastasis of the carcinoma. METHODS: In 29 patients who suffered from laryngeal or hypopharyngeal carcinoma with NO neck, the patent blue was injected into the surrounding tissue of the tumor during the operation to identify the sentinel lymph nodes. The sentinel lymph nodes were dyed blue. The frozen histopathology was done during the operation, the lymph nodes at the ipsilateral side of the neck were dissected completely, and the routine histopathology was done as the gold standard to study the predictive value of the sentinel lymph node in the metastasis of the cervical node. RESULTS: Of 29 patients, 28 patients' sentinel lymph nodes were detected successfully during operation. There was an average of 2.5 lymph nodes per side per patient. Most of the sentinel lymph nodes were in the level II and level III regions of the ipsilateral side of the neck, and there were bilateral sentinel nodes in patients suffered from superglottic carcinoma. Three patients' sentinel lymph nodes were found to be positive in the frozen inspection, and the routine histopathology confirmed the result. The micrometastasis rate was 10.7% (3/28). There were no metastatic lymph nodes found in patients who were negative for the sentinel lymph nodes during the operative frozen histopathology. The predicted value of the sentinel lymph nodes to the cervical lymph node metastasis was 100 per cent. CONCLUSION: There is a very important predicted value of sentinel lymph nodes in the cervical metastasis of patients suffered from laryngeal and hypopharyngeal carcinomas. It could reduce the neck dissection in patients with laryngeal and hypopharyngeal carcinomas.

Adult↗

PubMed2001

[Differentiation of natural killer cells into two functional subsets: NKh1 and NKh2].

OBJECTIVE: To verify the presence of functional subsets of natural killer cells based on the cytokine production. METHODS: NK cells were purified and cultured in complete RPMI1640 medium in the presence of either IFN gamma + anti-IL-4(classical Th1 polarization) or IL-4 + anti-IFN gamma (classical Th2 polarization) for three days, and then were collected and detected for type I/type II cytokines by RT-PCR method. RESULTS: NK cells were purified from 15 healthy donors, over 70% purity of NK cells were determined by flow cytometry. NK cells in peripheral blood expressed high level of type I cytokines, mainly IFN gamma, but low level of type II cytokines such as IL-10 and IL-13, IL-4 was not produced by NK cells. Cells cultured in IFN gamma + anti-IL-4 condition exhibited significantly increased level of IFN gamma, unchanged IL-2, and decreased type II cytokines. Cells grew in IL-4 + anti-IFN gamma condition exhibited increased IL-10 and IL-13, and decreased IFN gamma expressions. CONCLUSIONS: Based on the cytokine production, NK cells may be divided into two functional subsets in the same manner as that of T lymphocytes(e.g. Th1/Th2): NKh1 and NKh2. The biological characterization and phenotypic marker are under investigate.

Cells, Cultured↗

PubMed2001

[The clinical significance of detection of urinary ceruloplasmin in type 2 diabetes].

OBJECTIVE: To evaluate the clinical significance of detection of urinary ceruloplasmin (Cp) in type 2 diabetes. METHODS: To measure albumin/creatinine(Alb/Cr) and Cp/Cr in morning urinary specimens, from 134 normal controls and 3 960 diabetes, with RIA and ELISA separately. RESULTS: (1) The range of urinary Cp/Cr for normal controls was 0.01 - 1.12 ng/mmol, median 0.36 ng/mmol. Cp/Cr > 0.924 ng/mmol was considered as abnormal, and there was no significant difference between males and females, as well as among subjects of different age. (2) The sensitivity and specificity of Cp/Cr were 90% and 66% respectively with Alb/Cr > 2.5 mg/mmol as a golden standard for diabetic nephropathy, and Kappa value 0.48. Urinary Cp/Cr correlated well with Alb/Cr. (3)After sub-maximal exercise, Cp/Cr elevated markedly with no significant change of Alb/Cr. CONCLUSION: Urinary Cp/Cr could be considered as a marker of diabetic nephropathy and might be more sensitive than Alb/Cr.

Adult↗

PubMed2000

Synthesis of alpha-Gal epitope derivatives with a galactosyltransferase-epimerase fusion enzyme.

Alpha-Gal epitopes are carbohydrate structures bearing an alpha-D-Galp-(1-->3)-beta-D-Galp terminus and are the main cause of antibody-mediated hyperacute rejection in xenotransplantation. Nine monosaccharides and ten disaccharides were evaluated as substrates for a fusion protein, which contains both alpha-(1-->3)-galactosyltransferase and uridine-5'-diphosphogalactose 4-epimerase. Four disaccharide and six trisaccharide alpha-Gal epitope derivatives were synthesized utilizing this novel fusion enzyme.

Animals↗

PubMed2000

Differential gene expression between normal and tumor-derived ovarian epithelial cells.

The majority of ovarian tumors arise from the transformation of the ovarian surface epithelial cells, a single layer of cells surrounding the ovary. To identify genes that may contribute to the malignant phenotype of ovarian cancers, cDNA representational difference analysis was used to compare expressed genes in primary cultures of normal human ovarian surface epithelium (HOSE) and ovarian tumor-derived epithelial cells from the Cedars-Sinai Ovarian Cancer (CSOC) repository. A total of 255 differentially expressed genes were identified, of which 160 and 95 were specifically expressed in HOSE and CSOC cells, respectively. Using cDNA array hybridization, the expression profiles of the genes identified by cDNA-representational difference analysis were examined in an additional 5 HOSE and 10 CSOC lines. The comparison of average signal of each gene revealed 44 HOSE-specific and 16 CSOC-specific genes that exhibited at least a 2.5-fold difference in expression. A large number of genes identified in this study encode membrane-associated or secreted proteins and, hence, may be useful as targets in the development of serum-based diagnostic markers for ovarian cancer. Very few genes associated with protein synthesis or metabolism were identified in this study, reflecting the lack of observable differences in phenotypic or growth characteristics between HOSE and CSOC cells. Northern blot analysis on a subset of these genes demonstrated comparable levels of gene expression as observed in the cDNA array hybridization.

Blotting, Northern↗

PubMed2000

Mutations in FOXC2 (MFH-1), a forkhead family transcription factor, are responsible for the hereditary lymphedema-distichiasis syndrome.

Lymphedema-distichiasis (LD) is an autosomal dominant disorder that classically presents as lymphedema of the limbs, with variable age at onset, and double rows of eyelashes (distichiasis). Other complications may include cardiac defects, cleft palate, extradural cysts, and photophobia, suggesting a defect in a gene with pleiotrophic effects acting during development. We previously reported neonatal lymphedema, similar to that in Turner syndrome, associated with a t(Y;16)(q12;q24.3) translocation. A candidate gene was not found on the Y chromosome, and we directed our efforts toward the chromosome 16 breakpoint. Subsequently, a gene for LD was mapped, by linkage studies, to a 16-cM region at 16q24.3. By FISH, we determined that the translocation breakpoint was within this critical region and further narrowed the breakpoint to a 20-kb interval. Because the translocation did not appear to interrupt a gene, we considered candidate genes in the immediate region that might be inactivated by position effect. In two additional unrelated families with LD, we identified inactivating mutations-a nonsense mutation and a frameshift mutation-in the FOXC2 (MFH-1) gene. FOXC2 is a member of the forkhead/winged-helix family of transcription factors, whose members are involved in diverse developmental pathways. FOXC2 knockout mice display cardiovascular, craniofacial, and vertebral abnormalities similar to those seen in LD syndrome. Our findings show that FOXC2 haploinsufficiency results in LD. FOXC2 represents the second known gene to result in hereditary lymphedema, and LD is only the second hereditary disorder known to be caused by a mutation in a forkhead-family gene.

Adolescent↗

PubMed2000

Changing the donor cofactor of bovine alpha 1, 3-galactosyltransferase by fusion with UDP-galactose 4-epimerase. More efficient biocatalysis for synthesis of alpha-Gal epitopes.

Two fusion enzymes consisting of uridine diphosphogalactose 4-epimerase (UDP-galactose 4-epimerase, EC ) and alpha1, 3-galactosyltransferase (EC ) with an N-terminal His(6) tag and an intervening three-glycine linker were constructed by in-frame fusion of the Escherichia coli galE gene either to the 3' terminus (f1) or to the 5' terminus (f2) of a truncated bovine alpha1, 3-galactosyltransferase gene, respectively. Both fusion proteins were expressed in cell lysate as active, soluble forms as well as in inclusion bodies as improperly folded proteins. Both f1 and f2 were determined to be homodimers, based on a single band observed at about 67 kDa in SDS-polyacrylamide gel electrophoresis and on a single peak with a molecular mass around 140 kDa determined by gel filtration chromatography for each of the enzymes. Without altering the acceptor specificity of the transferase, the fusion with the epimerase changed the donor requirement of alpha1, 3-galactosyltransferase from UDP-galactose to UDP-glucose and decreased the cost for the synthesis of biomedically important Galalpha1,3Gal-terminated oligosaccharides by more than 40-fold. For enzymatic synthesis of Galalpha1,3Galbeta1,4Glc from UDP-glucose and lactose, the genetically fused enzymes f1 and f2 exhibited kinetic advantages with overall reaction rates that were 300 and 50%, respectively, higher than that of the system containing equal amounts of epimerase and galactosyltransferase. These results indicated that the active sites of the epimerase and the transferase in fusion enzymes were in proximity. The kinetic parameters suggested a random mechanism for the substrate binding of the alpha1, 3-galactosyltransferase. This work demonstrated a general approach that fusion of a glycosyltransferase with an epimerase can change the required but expensive sugar nucleotide to a less expensive one.

Animals↗

PubMed2000

Characterization of methanotrophic bacteria on the basis of intact phospholipid profiles.

The intact phospholipid profiles (IPPs) of seven species of methanotrophs from all three physiological groups, type I, II and X, were determined using liquid chromatography/electrospray ionization/mass spectrometry. In these methanotrophs, two major classes of phospholipids were found, phosphatidylglycerol (PG) and phosphatidylethanolamine (PE) as well as its derivatives phosphatidylmethylethanolamine (PME) and phosphatidyldimethylethanolamine (PDME). Specifically, the type I methanotrophs, Methylomonas methanica, Methylomonas rubra and Methylomicrobium album BG8 were characterized by PE and PG phospholipids with predominantly C16:1 fatty acids. The type II methanotrophs, Methylosinus trichosporium OB3b and CSC1 were characterized by phospholipids of PG, PME and PDME with predominantly C18:1 fatty acids. Methylococcus capsulatus Bath, a representative of type X methanotrophs, contained mostly PE (89% of the total phospholipids). Finally, the IPPs of a recently isolated acidophilic methanotroph, Methylocella palustris, showed it had a preponderance of PME phospholipids with 18:1 fatty acids (94% of total). Principal component analysis showed these methanotrophs could be clearly distinguished based on phospholipid profiles. Results from this study suggest that IPP can be very useful in bacterial chemotaxonomy.

Bacterial Typing Techniques↗

PubMed2000

Identification of the increased expression of monocyte chemoattractant protein-1, cathepsin S, UPIX-1, and other genes in dystrophin-deficient mouse muscles by suppression subtractive hybridization.

The lack of dystrophin results in muscular dystrophy characterized by degeneration, inflammation, and partial regeneration of skeletal muscles. The fate of these muscles may be determined by the extent of adaptation to the defect and the efficiency of regeneration that is affected by inflammatory cells. We have used suppression subtractive hybridization and quantitative Northern blot analysis to identify differentially expressed genes. Increased expression of murine monocyte chemoattractant protein-1 (JE/MCP-1), cathepsin S, UPIX-1, nmb, cathepsin B, and lysozyme M mRNAs were identified in 2-month-old mdx mouse leg muscles. UPIX-1 is a novel gene. Although it was not expressed in control muscles, it was expressed in control brain, heart, and spleen. JE/MCP-1 and cathepsin S proteins in mdx muscles, as well as JE/MCP-1 protein in the serum of mdx mice were also detected. JE/MCP-1 may be responsible for attraction of inflammatory cells, and cathepsin S, a potent elastolytic protease, may contribute to the remodeling of the extracellular matrix that is required for the migration of these cells to the injured muscles.

Animals↗