Biomedical subjects

Y J Wu

Publications and source records attributed to Y J Wu.

At least 37 records · Page 2Linked to original sources

PubMed2001

[Expression of heme oxygenase-1 in neonatal rat cardiocytes induced by lipopolysaccharide].

To study the alterations of heme oxygenase-1 mRNA in neonatal rat cardiomyocytes (NRCMs) induced by lipopolysaccharide (LPS) and the role of heme oxygenase-1 (HO-1) in the LPS induced disorders of myocardium function, 10 (L, 6 h), 30 (M, 6 h), 50 micrograms/ml (H, 6 h) LPS and 10 micrograms/ml LPS + 10 mumol/ml Zn-protoporphyrin-IX (ZnPPIX; L + I, 6 h) and 10 mumol/ml ZnPPIX alone (I, 6 h) were added to the medium for a 6-hour culture of NRCMs, and 10 micrograms/ml LPS for 9 h (L, 9 h) and 18 h (L, 18 h) cultures. LDH release and MDA contents of the cells were measured. When NRCMs were collected, Trypan blue stain method was used to examine the mortality (the rate of Trypan blue uptake) of NRCMs. HO-1 mRNA expression was examined by Northern blot. The results showed that HO-1 mRNA expression of NRCMs increased gradually along with the increase of LPS concentration below the level of 30 micrograms/ml. When the final concentrations of LPS were 10 and 30 micrograms/ml, the HO-1 mRNA expression of NRCMs increased by 81.2% and 126.3% respectively compared with control. When the final concentration of LPS was 50 micrograms/ml, the HO-1 mRNA expression decreased to the level of 10 micrograms/ml group. When the final concentration was 10 micrograms/ml, the HO-1 mRNA expression increased gradually along with the culture time. After a 9- or 18-hour culture, the HO-1 mRNA expression of NRCMs increased by 93.6% and 105.8% respectively compared with control. Only when NRCMs had been cultured with 30, 50 micrograms/ml LPS and 10 micrograms/ml LPS + 10 mumol/ml ZnPPIX for 6 h and 10 micrograms/ml LPS for 18 h, the rate of Trypan blue stain uptake, MDA contents and LDH release significantly increased. With 10 micrograms/ml LPS alone and 10 mumol/ml ZnPPIX alone for 6 h, the above parameters were not significantly increased (P > 0.05). The results demonstrate that LPS induces HO-1 mRNA expression of NRCMs dose- and time-dependently to some extent. The inducible HO can protect NRCMs from injury and thus play an important role in pathogenesis of myocardium under LPS.

Animals↗

PubMed2001

Correlation of acoustic velocity of synovial fluid with markers of inflammation in arthritic patients.

Analysis of synovial fluid is important in the evaluation and treatment of arthritic conditions. This study measured the acoustic velocity of synovial fluids in patients with degenerative joint diseases, crystal arthropathy, and other inflammatory arthropathies using the ultrasonic pulse-echo method. The measured acoustic velocities of these bio-fluids were then correlated with clinical parameters including the synovial white blood cell count (WBC), clarity, viscosity, string test, erythrocyte sedimentation rate (ESR), and serum C-reactive protein (CRP). Results showed that the acoustic velocities were correlated with ESR (p = 0.0016) and CRP (p = 0.0001). The mean acoustic velocity of inflammatory synovial fluids, defined as synovial fluids with WBCs of more than 2000/mm3, was greater than that of synovial fluids with WBCs of less than 2000/mm3 (1550 +/- 4.5 m/s vs 1544 +/- 1.5 m/s, p = 0.007). This study demonstrated that the acoustic velocity of synovial fluid correlates well with severity of inflammation. These findings suggest that measurement of acoustic velocity may be useful in the clinical evaluation and management of arthritic conditions.

Arthritis↗

PubMed2001

Effect of recombinant human basic fibroblast growth factor on acute inflammation in mice and rats.

AIM: To investigate the anti-inflammatory effects of recombinant human basic fibroblast growth factor (rh-bFGF). METHODS: Several inflammation models such as croton oil-induced ear swelling, carrageenan-induced hind paw edema, and acute peritonitis in rats or mice were prepared. Superoxide dismutase (SOD) activity was measured by hydroxyamine method, nitric oxide (NO) concentration by Griess reaction assay, nitric oxide synthase (NOS) activity by NADPH-diaphoras stain assay, N-acetyl-beta- D-glucosaminidase (NAG) activity by colorimetry, prostaglandin E2 (PGE2) production by radioimmunoassay (RIA), malondialdehyde (MDA) content by thiobarbituric acid (TBA) fluorescence technique, and protein content by Coomassie brilliant blue method in peritoneal exudate in rats. RESULTS: Recombinant human bFGF 2, 4 kU/kg im inhibited croton oil-induced ear swelling and carrageenan-induced paw edema in mice. In addition, rh-bFGF 2, 4 kU/kg im reduced neutrophil counts in the rat peritoneal exudate, and lessened protein content in peritoneal exudate in rats and mice. In the rat peritonitis induced by carrageenan, rh-bFGF 4 kU/kg decreased the MDA and NO levels, inhibited the NOS activity, augmented the SOD activity, and lowered the production of PGE(2) in exudate. However, rh-bFGF had no effect on NAG content. CONCLUSION: Recombinant human bFGF has an anti-inflammatory effect and its mechanisms are related to the inhibition of NOS activity, reduction of NO, MDA, and PGE(2) content, and increase of SOD activity.

Animals↗

PubMed2001

Effects of recombinant human basic fibroblast growth factor on restenosis after arterial endothelial injury in rats.

AIM: To study the preventive effect of recombinant human basic fibroblast growth factor (rh-bFGF) on restenosis after percutaneous transluminal coronary angioplasty (PTCA). METHODS: Sixty male Wistar rats were randomly divided into sham operation group, intima injured group, and intima injured plus rh-bFGF treated group. Rat carotid arteries were injured using a balloon catheter except sham operation group. The rats of rh-bFGF treated group were injected im rh-bFGF 10 kU . kg-1 . d-1 after intima was injured. Ten rats in each group were killed on d 7 and d 14 after injury, respectively. [3H]Thymidine incorporation assay and pathological examination were carried out to each vessel. RESULTS: (1) Seven days after injury, the average intimal thickness in sham operation group, intima injured group, and rh-bFGF treated group was (7 +/- 1), (32 +/- 11), and (17 +/- 3) micron; average intimal area was (384 +/- 145), (1530 +/- 817), and (586 +/- 185) micron2; the numbers of smooth muscle cells in neointima per transect were 0 +/- 0, 146 +/- 18, and 105 +/- 26; the ratio of the collagen area to intimal area plus medial area were 0.29 +/- 0.09, 0.7 +/- 0.3, and 0.30 +/- 0.14; [3H]thymidine incorporation were (17 +/- 6), (62 +/- 23), (20 +/- 8) kBq/g tissue, respectively. (2) Fourteen days after injury, the average intimal thickness of sham operation group, intima injured group, and rh-bFGF treated group was (8 +/- 1), (41 +/- 9), and (20 +/- 3) micron; average intimal area was (391 +/- 134), (1761 +/- 337), and (731 +/- 124) micron2; the numbers of smooth muscle cells in neointima per transect were 0 +/- 0, 145 +/- 9, and 102 +/- 6; the ratio of collagen area to intimal area plus medial area were 0.28 +/- 0.14, 0.59 +/- 0.21, and 0.38 +/- 0.03; [3H]thymidine incorporation was (15 +/- 4), (57 +/- 11), and (22 +/- 6) kBq/g tissue, respectively. CONCLUSION: Large dosage of rh-bFGF inhibits neointimal hyperplasia and reduces restenosis after balloon injury.

Angioplasty, Balloon, Coronary↗

PubMed2001

Anti-inflammatory effect and mechanism of proanthocyanidins from grape seeds.

AIM: To investigate the anti-inflammatory effect and mechanism of proanthocyanidins (PA) from grape seeds. METHODS: Croton oil-induced ear swelling in mice and carrageenan-induced hind paw edema in rats were prepared. The nitric oxide synthase (NOS) activity was measured by NADPH-diaphoras stain assay, nitric oxide (NO) content by Griess diazotization assay, N-acetyl-beta- D-glucosaminidase (beta-NAG) activity by spectrophotography, malondialdehyde (MDA) content by thiobarbituric acid (TBA) fluorescence technique, and IL-1beta, TNFalpha, and PGE2 content by radioimmunoassay (RIA). RESULTS: PA 10-40 mg/kg ip inhibited carrageenan-induced paw edema in rats and croton oil-induced ear swelling in mice in a dose-dependent manner. PA 10 mg/kg reduced MDA content in inflamed paws, inhibited beta-NAG and NOS activity, and lowered the content of NO, IL-1beta, TNFalpha, and PGE2 in exudate from edema paws of rats induced by carrageenan. The inhibitory effect of PA on all above indices was more evident than that of dexamethasone 2 mg/kg. CONCLUSION: PA has anti-inflammatory effect on experimental inflammation in rats and mice. Its mechanisms of anti-inflammatory action are relevant to oxygen free radical scavenging, anti-lipid peroxidation, and inhibition of the formation of inflammatory cytokines.

Animals↗

PubMed2001

[Clinical observation on small doses Tripterygium wilfordii polyglycoside combined with methotrexate in treating rheumatoid arthritis].

OBJECTIVE: To observe the effect and adverse reaction of small doses Tripterygium wilfordii polyglycoside (TWP) combined with methotrexate (MT) in treating rheumatoid arthritis (RA). METHODS: Seventy RA patients were randomly divided into two groups, the control group (35 patients) and the TWP combined MT Group (TWPM group). Both of them were continued to use the non-steroidal anti-inflammatory drugs. The control group took MT 15 mg orally, once every week; the TWPM group took TWP 10 mg orally, 3 times a day, and MT 7.5 mg orally once every week. The clinical effect and adverse reaction after treatment were evaluated. RESULTS: The markedly effective rate in the control group and the TWPM group was 28.6% and 34.3% respectively, with no significant difference (P > 0.05). Data of symptoms and signs, erythrocyte sedimentation rate (ESR), rheumatoid factor (RF) were determined respectively with significant difference (P < 0.01). The rate of adverse reaction was 20 cases-times in the control group and 8 cases-times in the TWPM group. CONCLUSION: MT combined small doses of TWP in treating RA has better effect and less adverse reactions than un-combined MT.

Adult↗

PubMed2000

The C termini of Arabidopsis cryptochromes mediate a constitutive light response.

Cryptochrome blue light photoreceptors share sequence similarity to photolyases, flavoproteins that mediate light-dependent DNA repair. However, cryptochromes lack photolyase activity and are characterized by distinguishing C-terminal domains. Here we show that the signaling mechanism of Arabidopsis cryptochrome is mediated through the C terminus. On fusion with beta-glucuronidase (GUS), both the Arabidopsis CRY1 C-terminal domain (CCT1) and the CRY2 C-terminal domain (CCT2) mediate a constitutive light response. This constitutive photomorphogenic (COP) phenotype was not observed for mutants of cct1 corresponding to previously described cry1 alleles. We propose that the C-terminal domain of Arabidopsis cryptochrome is maintained in an inactive state in the dark. Irradiation with blue light relieves this repression, presumably through an intra- or intermolecular redox reaction mediated through the flavin bound to the N-terminal photolyase-like domain.

Alleles↗

PubMed2000

On-column amperometric detection in capillary electrophoresis with an improved high-voltage electric field decoupler.

An improved fabrication method for a decoupler for on-column amperometric detection in capillary electrophoresis (CE) is described. The decoupler is fabricated by etching one side-wall of the capillary with hydrofluoric acid after the polymer coating had been etched by laser, then the etched hole is sealed with adhesive. The steady time, electric conductivity efficiency and performance are investigated. On-column amperometric detection by CE of para-substituted phenols was carried out by coupling with a carbon-fiber microelectrode (10-microm diameter) and a practical small electrochemical detection cell.

Electrochemistry↗

PubMed2000

Effects of tri-o-cresyl phosphate on serum estrogen and progesterone concentration and ATPase activity in the shell gland of adult hens.

The activities of calcium-activated ATPase (Ca2+-ATPase) and calcium magnesium-activated ATPase (Ca2+-Mg2+-ATPase) in the shell gland, and concentrations of 17beta-estradiol (E2) and progesterone in serum were monitored, respectively, from hens orally dosed with tri-o-cresyl phosphate (TOCP) (750 mg/kg). Treated birds were monitored daily for laying and development of delayed neurotoxicity, and activities of Ca2+-ATPase and Ca2+-Mg2+-ATPase were measured at 7 and 10 days after dosing. TOCP-treated birds manifested motor deficit by 7-9 days postdosing, while hens administered vehicle exhibited no signs of delayed neurotoxicity. Ca2+-ATPase and Ca2+-Mg2+-ATPase activities of shell glands from TOCP-dosed hens were not significantly affected (P > 0.05). The serum E2 concentration was significantly reduced in TOCP-treated hens (P < 0.01); however, progesterone levels were unaffected.

Administration, Oral↗

PubMed2000

Beta-cell dysfunction in 48-hour glucose-infused rats is not a consequence of elevated plasma lipid or islet triglyceride levels.

The abnormal insulin secretion found in human diabetics and animal models of diabetes has been attributed to the deleterious effects of chronic hyperglycemia and/or elevated circulating levels of nonesterified fatty acids (NEFAs). In this study, abnormal glucose-induced insulin secretion (GIIS) was generated by a 48-hour infusion of glucose and assessed by the isolated perfused pancreas technique. In these hyperglycemic animals, abnormal GIIS is accompanied by a decrease in plasma NEFAs, while plasma and, more importantly, islet triglycerides remain at levels comparable to those in the controls. It is concluded that the abnormal insulin secretion in this glucose infusion model was likely caused by 48 hours of hyperglycemia and not by changes in circulating or islet lipids.

Animals↗

PubMed2000

Abdominal fat pad mass reduction by in ovo administration of anti-adipocyte monoclonal antibodies in chickens.

The effect of in ovo administration of antiadipocyte monoclonal antibodies (MAb) on growth and adipose tissue development in chickens was investigated. In Trial 1, 60 fertilized eggs from layer-type chickens were injected into allantoic circulation with different amounts of MAb against chicken adipocyte plasma membranes (0, 0.05, 0.1, 0.2, and 0.4 mg) on Day 15 of embryogenesis. In Trial 2, 180 fertilized broiler eggs were injected into allantoic circulation with 0.2 mg MAb on Day 15 of embryogenesis. In Trial 1, high doses (0.2 and 0.4 mg) of MAb in in ovo injection reduced (P < or = 0.05) abdominal fat pad weight without affecting total body weight at 42 d of age. Only the highest dose (0.4 mg) significantly reduced hatch rate. In Trial 2, adipose tissue (pectoral, femoral, and abdominal), major organ (heart, liver, and spleen), and total body weights at 14 d of age were not affected by in ovo injection. Hatch success rate of eggs was not significantly different among treatments. However, by 6 wk of age, in ovo injection of MAb significantly reduced (P < or = 0.05) abdominal fat pad weight by more than 28%. This relative fat pad mass reduction occurred without affecting femoral or pectoral fat tissues. Total body weight and feed intake were not affected among treatments. Our experiments demonstrated for the first time that in ovo administration of anti-adipocyte MAb on Day 15 of embryogenesis reduced the chicken abdominal fat pad mass by 42 d of age without affecting growth or body weight.

Abdomen↗

PubMed2000

Inhibition of chicken adipocyte differentiation by in vitro exposure to monoclonal antibodies against embryonic chicken adipocyte plasma membranes.

Specific monoclonal antibodies (MAb) against adipocyte precursor antigens were developed. These MAb identified adipocyte precursors and reduced their prominence in primary stromal-vascular (SV) cultures by complement-mediated cytotoxicity or by inhibition of differentiation. Binding of antibodies to chicken adipocyte precursors was confirmed by immunofluorescence visual examination following secondary exposure to fluorescein isothiocyanate-conjugated goat antimouse IgG. Cross-reaction of MAb with muscle, kidney, liver, fibroblasts, and other cell types not containing lipid droplets was not observed in primary cultures. Adipocyte precursors were obtained from 18-d chick embryo adipose tissue by collagenase digestion to investigate complement-mediated cytotoxicity of preadipocytes. Cultures were maintained in Medium 199 with 5% fetal bovine serum (FBS) for 4 d. Subsequently, Medium 199 supplemented with 10% chicken serum initiated adipocyte differentiation. At Day 5 postinoculation, individual or combinations of MAb were administered to preadipocyte cultures; rabbit complement was added 30 min later. After 1 d of incubation, four of the six individual MAb with complement significantly (P < 0.05) reduced the number of fat cell clusters that developed by 40 to 60%. These MAb in the presence of complement also significantly (P < 0.05) reduced mean cell width and apparent cell area or cell cluster area of lipid-containing cells. Neither MAb nor complement alone reduced fat cell cluster number, cell size, or cluster size. Treatment with pools of two and four MAb decreased the total amount of MAb protein required to reduce fat cell cluster number. Four antibodies, alone or in combination, reduced fat cell cluster development in a complement-dependent manner.

Adipocytes↗

PubMed2000

The clinical features and prognosis of lupus with disease onset at age 65 and older.

Systemic lupus erythematosus (SLE) in the elderly is uncommon and rarely reported with disease onset at age 65 and older. The aim of this study is to retrospectively analyze the influence of age at disease onset on the clinical features and prognosis of SLE. From 1988 to 1998, we encountered 21 lupus patients with disease onset at age 65 and older (all are included in group A). For comparison, 21 lupus patients with disease onset between 50-64 years of age (group B) and 152 lupus patients with disease onset before 50 years of age (group C) were obtained by a simple random sampling method from the hospital registry. Clinical features as included in the 1982 ARA revised criteria for classification of SLE and survival rate were analyzed and compared among these three groups. Group A had a smaller female to male ratio, longer duration from disease onset to diagnosis, less malar rash, more discoid lupus, and shorter survival rate that group C. There was no statistically significant difference in clinical features and survival between groups A and B, as well as between female and male patients of these two groups. The main cause of death in group A was septic shock. In conclusion, the clinical features and prognosis of SLE were influenced by the age at disease onset. However, clinical features and prognosis of SLE were similar in both late-onset lupus groups.

Adult↗

PubMed2000

Highlights of semi-synthetic developments from erythromycin A.

Earlier semi-synthetic studies of erythromycin A culminated in the discovery of two successful second generation macrolide antibiotics, azithromycin and clarithromycin, for the treatment of community-acquired bacterial infections. More recent structural modifications of erythromycin A have resulted in the discovery of novel ketolide antibiotics and new motilide prokinetic agents. This review is an account of the semi-synthetic developments from erythromycin A by chemical transformations.

Anti-Bacterial Agents↗

PubMed2000

[Mutants of subtilisin E].

Ser 236, located in the surface of subtilisin E and at the end of alpha-helex with Ser221, is far from the active center (Asp32, His64, Ser221). The replacement of Ser236 with Cys via directed-mutagenesis should effect protease activity insignificantly and may be able to improve the stability of enzyme due to the potency to form disulfide across two molecules. The results indicated that BP-1 (Ser236Cys) was found to gain 150% activity (Kcat/Km value) of the wild-type subtilisin E and 3-fold increase in stability in aqueous solution at pH7.4 and 50 degrees C, compared to the wild-type enzyme. However, further mutations on BP-1 to introduce Ala15Asp/Gly20His (BU-1) or Ser24His/Lys27Asp (BW-1) was found negative effects on the activity and stability of subtilisin E.

Enzyme Stability↗

PubMed2000

[Site-directed mutagenesis and effects on the enzymatic properties of subtilisin E].

Site-directed mutagenesis was used to investigate the effects of S221C/P225A, N118S/S221C/P225A, D60N/N118S/S221C/P225A and Q103R/N118S/S221C/P225A mutations on the properties of Subtilisin E. It was found that S221C/P225A mutant is 73,000-fold decreased in amidase activity than subtilisin E and 3-fold increased than subtiligase in the ratio of esterase/amidase; N118S/S221C/P225A mutant has 3.6-fold and 15-fold decreased in amidase and esterase activity respectively and as a result, it has a 4-fold lower in the ratio of amidase/esterase than S221C/P225A mutant; Although it has no effect on the esterase activity, D60N/N118S/S221C/P225A mutant enhanced its ratio of amidase/esterase by 15 fold, 3.3-fold and 10.3 fold compared to N118S/S221C/P225A mutant, S221C/P225A mutant and subtiligase respectively; Q103R/N118S/S221C/P225A mutant, however, has a 5-fold enhanced in the amidase activity and 55-fold and 1000-fold decrease in the esterase activity and the ratio of esterase/amidase compared to N118S/S221C/P225A.

Amidohydrolases↗

PubMed2000

[Gene cloning, expression and purification of its production of recombinant human superoxide dismutase].

Human SOD cDNA was cloned and constructed an expression plasmid with high sufficient and stabilility expression in E. coli. The rhSOD cDNA was amplified by RT-PCR with the template of the total RNA extracted from human liver tissue. The expression plasmid, pLY-4/rhSOD, containing rhSOD cDNA, was transformed into the E. coli JF1125. The sequence of the cloned rhSOD cDNA was identified with the reported data. The expression level reached to more than 68% of total bacteria proteins; The technology for protein renature and purification was efficiency and fast. The purity of the final products reached more than 98%. The value of bioactivity was determined as 2529 u/mg. This study gave enough support for production of rhSOD by biotechnology.

Cloning, Molecular↗

PubMed2000

[Effect of extract from overground part of Tripterygium wilfordii Hook. f. on Masugi nephritis in rabbits].

OBJECTIVE: To observe the effect of extract from overground part of Trpterygium wilfordii on Masugi nephritis in rabbits. METHOD: Masugi nephritis was made by giving i.v. the rabbit an injection of sheep antirabbit serum. RESULT: The extract could effectively inhibit the increase of uric protein, serum BUN, creatinine and glomerulus cells in rabbits. CONCLUSION: The extract from overground part of Tripterygium wilfordii has better curative effect on Masugi nephritis in rabbits.

Albuminuria↗