Biomedical subjects

Fang Fang

Publications and source records attributed to Fang Fang.

At least 91 records · Page 5Linked to original sources

PubMed2004

[Thermo-alkali-stable catalase from Thermoascus aurantiacus and its potential use in textile bleaching process].

The effect of growth and fermentation conditions on the production of catalase by T. aurantiacus WSH 03-01 was investigated in shaking flasks. Catalase activity reached 1594 u/mL when the culture was grown on a complex carbon source containing 20 g/L dextrin and 1% (V/V) ethanol, which was 23% higher than the sum produced on 20 g/L dextrin and 1% (V/V) ethanol, respectively. It was concluded that dextrin might act as a major carbon source in the complex, while ethanol was rather a stimulator than a carbon source. The stimulation effect of ethanol on catalase production was postulated to be two aspects; catalase-dependent alcohol metabolism is activated by acute alcohol, thus more catalase need to be synthesized for that use, named direct induction. As for indirect induction, which may result from little amount of H2O2 generation in process of NADH regeneration in respiratory chain. Peptone was shown to be a favorable nitrogen source for catalase production and its optimum concentration was found to be 10 g/L. Catalase production by T. aurantiacus WSH 03-01 was further improved by optimizing the initial pH, volume of medium in flasks as well as the concentration of external H2O2. Under the optimum culture conditions, the activity of catalase reached 2762 u/mL, which was nearly 6.8 times higher than that of the initiate conditions. Furthermore, the potential application of this novel catalase in the treatment of textile bleaching effluents was evaluated. Thermo-and alkaline stability of this catalase was compared with the commercial available catalases produced from bovine and Aspergillus niger. The crude enzyme from T. aurantiacus WSH 03-01 showed stronger stabilities at (70 degrees C, 80 degrees C, 90 degrees C) and (pH 9.0, pH 10.0, pH 11.0) than the other two types of catalases, indicating a great application potential in the clean production process of textile industry.

Catalase↗

PubMed2004

[Effect of jiuxinfumai injection on L-type calcium currents in single guinea pig ventricular myocytes].

OBJECTIVE: To determine the effect of 311 and 417, both active ingredients isolated from Jiuxinfumai injection (Citrus Aurantium) on L-type calcium currents (I(Ca-L)) in ventricular myocytes of guinea pigs. METHODS: Single myocytes were dissociated by enzymatic dissociation method. The whole-cell patch-clamp recording technique was used to record the change of calcium current after the administration of 311and 417. RESULTS: 311 (10, 25, 50, 100 mmol/L) increased the (I(Ca-L)) by 8.27%, 27.29%, 41.01%, and 48.74% (P < 0.05), respectively. 417 (10, 25, 50, 100 mmol/L) increased the (I(Ca-L)) by 10.05%, 30.12%, 43.05%, and 51.90% (P < 0.05), respectively. Both 311 and 417 changed the (I(Ca-L)) significantly in a concentration-dependent manner. They did not change the shape of I-V cruves. CONCLUSION: 311 and 417 can increase I(I(Ca-L)) n ventricular myocytes of guinea pigs in a dose-response manner.

Animals↗

PubMed2003

Viral receptor blockage by multivalent recombinant antibody fusion proteins: inhibiting human rhinovirus (HRV) infection with CFY196.

Viral receptor blockage by monoclonal antibodies (mAbs) is a common strategy to inhibit viral infection; however, no drug candidate acting by this mechanism has reached the market so far. Analysis of the experimental and clinical data on a receptor-blocking mAb, mAb 1A6, against human rhinovirus (HRV) major receptor intercellular adhesion molecule 1 (ICAM-1) reveals that insufficient avidity of the mAb is probably the key factor to blame for its unsatisfactory clinical efficacy. In this article, we have summarized the recently published work from Perlan Therapeutics, Inc. and others that involves creation of multivalent Fab fusion proteins against the HRV major receptor ICAM-1. The multivalent Fab fusion proteins have exhibited much improved avidities over conventional mAbs, as well as superior HRV inhibition in vitro. This work has led to a promising drug candidate, CFY196, for prevention and treatment of HRV infections. Multivalent recombinant Fab fusion proteins may herald a new generation of potent antiviral receptor blockers and other therapeutic molecules.

Antibodies, Monoclonal↗

PubMed2003

Ginsenoside Rg1 attenuates dopamine-induced apoptosis in PC12 cells by suppressing oxidative stress.

In Parkinson's disease, neuroprotective therapy to rescue dopamine neurons has been proposed. Ginsenoside Rg1, one of the biologically active ingredients of ginseng, may be a candidate neuroprotective drug. In the present study, the mechanism underlying the neuroprotection provided by ginsenosde Rg1 was studied against apoptosis induced by exogenous dopamine in PC12 cells. Pretreatment with ginsenoside Rg1 markedly reduced the generation of dopamine-induced reactive oxygen species and the release of mitochondrial cytochrome c into the cytosol, and subsequently inhibited the activation of caspase-3. In addition, Rg1 pretreatment also reduced inducible nitric oxide (NO) synthase protein level and NO production. These results suggested that ginsenoside Rg1 may attenuate dopamine-induced apoptotic cell death through suppression of intracellular oxidative stress, and that it may rescue or protect dopamine neurons in Parkinson's disease.

Animals↗

PubMed2003

Humanization of an anti-ICAM-1 antibody with over 50-fold affinity and functional improvement.

The monoclonal antibody 1A6 binds to human intercellular adhesion molecule 1 (ICAM-1, CD54) and inhibits infection by 90% of human rhinovirus (HRV) serotypes. To make a therapeutic molecule for preventing and treating HRV infection, we humanized a single chain antibody (scFv), 1A6, by a structure-guided complementarity-determining region (CDR) grafting procedure. Our final humanized 1A6 scFv does not retain any mouse back mutations in the framework. Without changing the CDR sequences, the humanized 1A6 scFv demonstrates over 50-fold improvement in both affinity for ICAM-1 and protection efficacy against HRV infection in vitro.

Amino Acid Sequence↗

PubMed2003

Lie detection with contingent negative variation.

topographies of contingent negative variation (CNV) were recorded in a paradigm of delayed response with feedback for three kinds of faces: familiar, strange and target. Subjects made responses to the faces according to whether the faces were familiar or not, but also, gave deliberately deceptive responses to target faces to 'cheat the computer'. Subjects were told that the computer could judge whether they were being honest or not. For each trial of the experiment, if subjects cheated the computer successfully and their responses were judged as honest and they were given a reward, otherwise they received a penalty. In this simulated lie detection test, CNV exhibited more negative shifts for target than those for non-target (familiar and strange). These differences could be accounted for by subjects' motivation and uncertainty about passing the test. With the results of further paired t-tests between target and non-target faces at each electrode, CNV was demonstrated as a reliable indicator for lie detection. In addition, vector length was used to capture global CNV information and was found to be a very good indicator, even better than the CNV information at the individual electrode sites.

Adolescent↗

PubMed2003

Prevention of human rhinovirus infection by multivalent fab molecules directed against ICAM-1.

We have developed a technology for improving avidity by making bivalent, trivalent, or tetravalent recombinant polypeptides. We designed tripartite proteins consisting of the Fab fragment of an antibody fused with a hinge derived from human immunoglobulin D that was further linked to polymerization domains derived from human coiled-coil proteins. We report here on the application of this method with a Fab domain directed against the major human rhinovirus receptor, intercellular adhesion molecule 1 (ICAM-1). Multivalent anti-ICAM-1 molecules were produced in bacteria and purified as soluble preassembled homogeneous proteins at high yield. These proteins successfully blocked rhinovirus infection in vitro, with the efficiency increasing from monomer to dimer, trimer, and tetramer. The diminished dissociation rate of these multivalent antibodies and their improved efficacy in preventing rhinovirus infection provide a foundation for producing prophylactic and therapeutic molecules against human rhinovirus, the causative agent of the majority of common colds.

Amino Acid Sequence↗

PubMed2003

[Ginsenoside Rg1 may protect SHSY5Y cells from apoptosis induced by MPP+ through JNK way].

AIM: To explore possible signal transmission way through which ginsenoside Rg1 protect cells from MPP(+)-induced apoptosis. METHODS: The apoptosis of SHSY5Y induced by 1-methyl-4-phenylpyridinium (MPP+) was observed by AO-EB staining. Flow cytometry was used to quantitate the reactive oxygen species (ROS). Western Blotting was used to detect the c-jun NH2-terminal kinase (JNK) activity in SHSY5Y cells. Immunocytochemistry staining was used to detect cleaved Caspase-3 positive cells. RESULTS: MPP+ was shown to induce apoptosis in SHSY5Y cells. The percentage of apoptotic SHSY5Y cells induced by MPP+ was obviously lower in those groups pretreated with 10 mumol.L-1 Rg1 or 2.5 mmol.L-1 N-acetylcysyteine (NAC). It showed more ROS in MPP+ groups than in control. JNK activity increased with time within 72 hours in 1 mmol.L-1 MPP+ group. Simultaneously, it showed decrease of ROS, less activity of JNK and lower expression of cleaved Caspase-3 in 10 mumol.L-1 Rg1 and 2.5 mmol.L-1 NAC pretreated groups compared with groups treated with MPP+ only. CONCLUSION: Rg1 protects against MPP(+)-induced apoptosis in SHSY5Y cells and the effect might be attributed to its removal of ROS, inhibition of the activity of JNK and expression of cleaved Caspase-3.

1-Methyl-4-phenylpyridinium↗

PubMed2003

[Study of body mass index and waist circumference in association with blood pressure in adult Guangzhou residents].

OBJECTIVE: To assess the significance of body mass index (BMI) and waist circumference (WC) measurement in hypertension prediction and diagnosis and formulate the recommended values for these two indexes, aiming to provide scientific basis for determining the indicators and their cut-off points for obesity diagnosis in Chinese subjects. METHODS: A total of 1 265 residents over 20 years old were randomly selected from Yuexiu District of Guangzhou City in our multiphase study. Questionnaire-based survey was conducted in conjunction of the measurement of the height, body weight, WC and blood pressure, the results subjected to multivariate linear regression and logistic regression. RESULTS: The distribution of BMI varied significantly with gender and age with the subjects. The mean systolic and diastolic blood pressures both gradually increased with BMI, showing obvious linear relationship between BMI and blood pressure. After such factors as age, gender and education background etc were controlled, logistic regression analysis revealed that the risk for hypertension increased with BMI elevation. WC was related to the blood pressure in similar manner as BMI. CONCLUSIONS: We suggest that BMI be used as the indexes for overweight and obesity, the diagnoses of which are established in cases with BMI >or=23 and BMI >or=29 respectively. As the diagnostic index for abdominal obesity, the cut-off point of WC >or=80 cm should be instituted.

Adult↗

PubMed2003

Effects of "moxibustion serum" on proliferation and phenotypes of tumor infiltrating lymphocytes.

Tumor infiltrating lymphocytes (TIL) were cultured with "moxibustion serum" (MS), and the results were examined by flow cytometry. The results indicated that MS could enhance the proliferation of TIL, accelerate it to reach the exponential growth phase, and assist recombinant interleukin 2 (rIL-2) to enhance successively the percentage of CD3+ positive cells, maintain the number of CD4+ positive T cells, promote greatly the percentage of CD8+ positive T cells among TILs, and reverse the CD4+/CD8+ ratio. Such cooperative effects rely on relative specificity of acupoints. It is suggested that MS is beneficial to the growth of TIL both in the aspects of proliferation and phenotypes.

Animals↗

PubMed2003

[Effect of Citrus aurantium extract on L-type calcium currents in ventricular myocytes of single guinea pigs].

OBJECTIVE: To determine the effect of citrus aurantium extract (CAE) on L-type calcium currents (ICa-L) in ventricular myocytes of guinea pigs. METHODS: Single myocytes were dissociated by enzymatic dissociation method. The whole-cell patch-clamp recording technique was used to record the change of calcium current after the administration of CAE. RESULTS: 1. CAE 4 x 10(-3), 2 x 10(-2), 4 x 10(-2), and 1 x 10(-1) g/ml increased the ICa-L by 15.89%, 29.01%, 52.03% and 59.76% (P < 0.05), respectively. 2. CAE 2 x 10(-1) and 4 x 10(-1) g/ml decreased the ICa-L by 16.61% and 30.87% (P < 0.05), respectively. CAE changed the ICa-L significantly, but did not change the shape of I-V curves. CONCLUSIONS: CAE 4 x 10(-3)-1 x 10(-1) g/ml can increase the L-type calcium current in guinea pig ventricular myocytes significantly in a concentration-dependent manner, and promote the opening of calcium channel. CAE 2 x 10(-1)-4 x 10(-1) g/ml may inhibit the L-type calcium channels of ventricular myocytes, and depress the opening of calcium channel.

Animals↗

PubMed2003

Involvement of CDK4, pRB, and E2F1 in ginsenoside Rg1 protecting rat cortical neurons from beta-amyloid-induced apoptosis.

AIM: To explore the possible mechanism of beta-amyloid (Abeta)-induced apoptosis in rat cortical neurons and the protective effect of ginsenoside Rg1. METHODS: AO-EB staining was used to quantify the apoptotic cells. DNA fragmentation was observed by gel electrophoresis. The levels of cyclin-dependent kinases-4 (CDK4) and phosphorylated pRB were detected by Western blot. RT-PCR was used to examine the expression of E2F1 mRNA. RESULTS: Treatment with Abeta1-40 at the concentration of 20, 40, 80 mg/L for 48 h induced rat cortical neuron apoptosis from 12.5 %+/-1.5 % (control) to 22.3 %+/-1.4 %, 38.8 %+/-1.3 %, 36.7 %+/-1.4 %, respectively. Pretreatment with Rg1 at the dose of 0.5, 1, 2, 4, 8, 16 micromol/L for 24 h, then treatment with Abeta1-40 40 mg/L for 24 h, the percentage of apoptotic neurons decreased from 38.8 %+/-1.3 % to 14.5 %+/-1.3 %, 13.3 %+/-1.0 %, 11.6 %+/-0.29 %, 11.8 %+/-1.0 %, 6.2 %+/-0.8 %, 5.8 %+/-0.8 %, respectively. After treatment with Abeta1-40 40 mg/L for 24 h, there were transient increases in CDK4 and phosphorylated pRB protein level, as well as the expression of E2F1 mRNA. However, the above levels decreased markedly after pretreatment with Rg1 8 micromol/L for 24 h. CONCLUSION: Ginsenoside Rg1 attenuated Abeta1-40-induced apoptosis in rat cortical neurons via inhibiting the activity of CDK4, decreasing the phosphorylation of pRB and downregulating the expression of E2F1 mRNA.

Amyloid beta-Peptides↗

PubMed2003

Are you my mother? Bayesian phylogenetic inference of recombination among putative parental strains.

Reconstructing evolutionary relationships using Bayesian inference has become increasingly popular due to the ability of Bayesian inference to handle complex models of evolution. In this review we concentrate on inference of recombination events between strains of viruses when these events are sporadic, ie rare relative to point mutations. Bayesian inference is especially attractive in the detection of recombination events because it allows for simultaneous inferences about the presence, number and location of crossover points and the identification of parental sequences. Current frequentist recombination identification falls into a sequential testing trap. The most likely parental sequences and crossover points are identified using the data and then the certainty of recombination is assessed conditional on this identification. After briefly outlining basic phylogenetic models, Bayesian inference and Markov chain Monte Carlo (MCMC) computation, we summarise three different approaches to recombination detection and discuss current challenges in applying Bayesian phylogenetic inference of recombination.

Algorithms↗

PubMed2002

A facile synthesis of cis-1-methyl-1,2,3,3a,4,8b- hexahydropyrrolo[3,2-f]pyrindine, an annulated nicotine analog.

[reaction: see text] The title compound, 2, has been synthesized in 45% overall yield in six steps from 3-bromopyridine. The hexahydropyrrolo[3,2-f]pyrindine skeleton was constructed from key intermediate 5, via intramolecular azomethine ylide-alkene [3 + 2] cycloaddition. The present work constitutes a general method for rapid assembly of other related tricyclic nicotine analogues.

Ligands↗

PubMed2002

[Four surgical patterns of hysterectomy for uterine without prolapsis: a clinical study].

OBJECTIVE: To evaluate the clinical effects of the four surgical patterns of hysterectomy for uterine without prolapsis. METHODS: Six hundred and eight patients with different gynecological diseases were operated upon by transvaginal hysterectomy (TVH, 78 cases), laparoscopically assisted vaginal hysterectomy (LAVH, 102 cases), classical intrafascial supracervical hysterectomy (CISH, 228 cases), or transabdominal hysterectomy (TAH, 200 cases). The clinical effects of these surgical patterns were analyzed. RESULTS: The success rate was 100% for TVH, 99.1% for CISH, and 98.0% for LAVH. The bleeding time and bleeding amount were significantly shorter or less in the TVH group than in the other 3 groups (P < 0.05), without a significant difference among the 3 groups. The percentage of analgesic use and postoperative morbidity were significantly higher in the TAH group than in the other 3 groups (P < 0.01), without a significant difference among the 3 groups. The days of hospitalization in the TAH group were significantly more than those in the other 3 groups (P < 0.05), without a significant difference among the 3 groups. The hospitalization expense was greater in the LAVH and CISH groups than in the TVH and TAH groups Except 2 cases of damages to the supravesical artery or ureter occurring during the early stage of CISH group, no surgical damage was found. CONCLUSION: Highly effective and with less injury, minimally invasive surgery in hysterectomy is worth spreading. LAVH and CISH apply in the cases with severe pelvic adhesion, with adhesive adnexa to be resected, or with adnexal cyst > 5 cm. CISH and TAH apply in the uterine larger than 16 weeks pregnant size. LAVH and TAH apply in the cases highly suspected as malignant diseases of uterine or endometrium.

Adult↗

PubMed2002

Pharmacokinetic interactions between protease inhibitors and statins in HIV seronegative volunteers: ACTG Study A5047.

OBJECTIVE: Lipid lowering therapy is used increasingly in persons with HIV infection in the absence of safety data or information on drug interactions with antiretroviral agents. The primary objectives of this study were to examine the effects of ritonavir (RTV) plus saquinavir soft-gel (SQVsgc) capsules on the pharmacokinetics of pravastatin, simvastatin, and atorvastatin, and the effect of pravastatin on the pharmacokinetics of nelfinavir (NFV) in order to determine clinically important drug-drug interactions. DESIGN: Randomized, open-label study in healthy, HIV seronegative adults at AIDS Clinical Trials Units across the USA. METHODS: Three groups of subjects (arms 1, 2, and 3) received pravastatin, simvastatin or atorvastatin (40 mg daily each) from days 1-4 and 15-18. In these groups, RTV 400 mg and SQVsgc 400 mg twice daily were given from days 4-18. A fourth group (arm 4) received NFV 1250 mg twice daily from days 1-14 with pravastatin 40 mg daily added from days 15-18. Statin and NFV levels were measured by liquid chromatography/tandem mass spectrometry. RESULTS: Fifty-six subjects completed both pharmacokinetic study days. In arms 1-3, the median estimated area under the curves (AUC)(0-24) for the statins were: pravastatin (arm 1, n = 13), 151 and 75 ng.h/ml on days 4 and 18 (decline of 50% in presence of RTV/SQVsgc), respectively (P = 0.005); simvastatin (arm 2, n = 14), 17 and 548 ng.h/ml on days 4 and 18 (increase of 3059% in the presence of RTV/SQVsgc), respectively (P < 0.001); and total active atorvastatin (arm 3, n = 14), 167 and 289 ng.h/ml on days 4 and 18 (increase of 79% in the presence of RTV/SQVsgc), respectively (P < 0.001). In arm 4, the median estimated AUC(0-8) for NFV (24 319 versus 26 760 ng.h/ml; P = 0.58) and its active M8 metabolite (15 565 versus 14 571 ng.h/m; P = 0.63) were not statistically different from day 14 to day 18 (without or with pravastatin). CONCLUSIONS: Simvastatin should be avoided and atorvastatin may be used with caution in persons taking RTV and SQVsgc. Dose adjustment of pravastatin may be necessary with concomitant use of RTV and SQVsgc. Pravastatin does not alter the NFV pharmacokinetics, and thus appears to be safe for concomitant use.

Adult↗

PubMed2002

[Therapeutic effect of recombinant human interleukin-11 on thrombocytopenia models induced by anti-platelet serum in guinea pigs].

OBJECTIVE: To observe the effect of recombinant human interleukin-11 on the platelet counts and the CFU-Meg of the marrow cell culture. METHODS: Thrombocytopenia models of guinea pigs were made by injecting subcutaneously anti-platelet serum. RESULTS: 200, 100, and 50 micrograms.kg-1 of rHuIL-11 increased the CFU-Meg of the marrow cell culture and the peripheral platelet, showing a significant difference from that of the control group (P < 0.05). CONCLUSION: rHuIL-11 has a significantly therapeutic effect on thrombocytopenia models induced by anti-platelet serum in guinea pigs.

Animals↗

PubMed2002

Determination of nelfinavir free drug concentrations in plasma by equilibrium dialysis and liquid chromatography/tandem mass spectrometry: important factors for method optimization.

A method was developed and validated for measuring the free fraction of nelfinavir in plasma employing equilibrium dialysis for the separation of free (unbound) drug and liquid chromatography/tandem mass spectrometry for quantitation. Nelfinavir, widely used to treat HIV infection, is a highly bound HIV protease inhibitor with the fraction bound in plasma being greater than 98%. Thus variations in the free fraction may be clinically important when interpreting total drug concentrations. Optimization of the method was carried out considering the influence of sample matrix and physicochemical and absorptive properties of nelfinavir. Nelfinavir free fraction averaged 0.41 +/- 0.094, 0.43 +/- 0.087 and 0.41 +/- 0.063% at nelfinavir plasma concentrations of 1000, 2000 and 3000 ng/ml, respectively. Free nelfinavir concentrations were underestimated with this assay by approximately 25% because of unavoidable losses to adsorption. However, the adsorptive loss was reproducible and consistent across the concentration range of the assay. Within-day and between-day precisions ranged from 6.0 to 9.4% and 15.2 to 27.3%, respectively. The lower limit of quantitation of the unbound concentration of nelfinavir was 1.0 ng/ml, permitting analysis of samples with total concentrations of nelfinavir in plasma that are > or = 400 ng/ml. This developed method proves reproducible and sensitive and its application to patient plasma samples is also reported.

Adsorption↗