Biomedical subjects

Bin Hu

Publications and source records attributed to Bin Hu.

At least 55 records · Page 3Linked to original sources

PubMed2005

Photoacoustic phase study on the frequency dependence of phase angle and triplet state lifetime of Nd(III)-acetylacetonate.

The amplitude and phase of the photoacoustic (PA) signal generated in the rare earth complex powder of Nd(III)-acetylacetonate (Nd(AA)3) were examined. By using the reasonably simplified formula about phase angle at the wavelengths assigned to pi-pi* transition of ligand and f-f transitions of Nd3+, the instrumental contribution to phase angle at different chopping frequency was calculated. The frequency dependence of sample phase angle, the relative phase angle shift caused by instrumental factors and the calculation of triplet state lifetime of sample under study were also discussed. Being independent of sample, the instrumental contribution to phase angle was regarded as a parameter representing the situations of instruments and measurement and it became an approach to calculate the relaxation time of ligand in rare earth complex.

Acoustics↗

PubMed2005

[Effect of weight loss induced by laparoscopic adjustable gastric banding on immunity of morbid obesity].

OBJECTIVE: To compare the immunity of morbid obesity (MO) before and after laparoscopic adjustable gastric banding (LAGB). METHODS: 15 cases, with a mean body mass index (BMI) of 35.8 kg/m(2), were treated by LAGB from Jun. 2003 to Oct. 2003 in our department. Patients' immune parameters were determined preoperatively and 1, 3 and 6 months postoperatively. 15 cases with a normal BMI (23.6 kg/m(2)) were set as controls. RESULTS: Before surgery, the MO had a significant lower level of CD(4)(+), CD(4)(+)/CD(8)(+) and a higher level of serum interleukin-2 (IL-2), Interleukin-6 (IL-6) than the controls (P < 0.01). There was a significant reduction of weight and BMI 6 months postoperatively (P < 0.01). At the same time, CD(4)(+) increased and serum IL-2 decreased significantly. But CD(4)(+)/CD(8)(+)and serum IL-2, IL-6 were still abnormal compare to the controls. CONCLUSIONS: MO may combined with an abnormal immunity. But after enough weight loss induced by LAGB, it can be partly reversed.

Adolescent↗

PubMed2005

Molecular characterization and immunohistochemical localization of palmdelphin, a cytosolic isoform of the paralemmin protein family implicated in membrane dynamics.

Palmdelphin is a newly identified cytosolic isoform of paralemmin-1, a lipid raft-associated protein implicated in cell shape control. Like paralemmin-1, palmdelphin is phosphorylated, giving rise to electrophoretic band heterogeneity that is most pronounced in the brain. In ultracentrifugation and gel filtration palmdelphin behaves as a non-globular monomer. Its C-terminal region binds glutamine synthetase. Immunohistochemical analysis of the rat brain shows a prominent localization of palmdelphin in the cerebral cortex, hippocampus, amygdala, septum, indusium griseum, piriform cortex, nucleus supraopticus, and nucleus of the lateral olfactory tract. Many of the circumscript palmdelphin-positive areas are related to the olfactory system. Immunoperoxidase electron microscopy reveals a discontinuous distribution of palmdelphin immunoreactivity, in the form of spots scattered throughout the cytoplasm of selected neuronal perikarya and dendrites, including dendritic spines, often in association with endomembranes, and in a pattern which is similar to that of the cytoplasmic fraction of paralemmin-1. In subcellular fractionation experiments palmdelphin behaves as a cytosolic protein which, however, can be partially recruited from cytosol to the detergent-resistant fraction of a membrane/cytoskeletal cell ghost preparation. These observations suggest that palmdelphin may peripherally associate with endomembranes or cytoskeleton-linked structures.

Amino Acid Sequence↗

PubMed2005

Enhanced antitumor effect of the combination of tumstatin gene therapy and gemcitabine in murine models.

Targeting tumor endothelium is an important strategy for cancer therapy. We evaluated the effectiveness of gene therapy, that is, intramuscular delivery of plasmid DNA encoding tumstatin (pSecTag2B-tum), combined with gemcitabine administration in vitro and in vivo, using colon carcinoma (CT26) and Lewis lung carcinoma (LLC) murine models. The in vitro growth-inhibitory and proapoptotic effects of gemcitabine and/or tumstatin on human umbilical vein endothelial cells (HUVECs) and mouse endothelial cells (SVEC4-10), respectively, were assessed. in vitro, conditioned medium from pSecTag2B-tum-transfected COS cells inhibited the growth of endothelial cells but not of CT26 or LLC cells, whereas gemcitabine inhibited the growth of both endothelial cells and CT26 and LLC cells. Mice bearing subcutaneously established CT26 or LLC tumors received pSecTag2B-tum alone or in combination with gemcitabine to assess tumor growth inhibition. in vivo, combined treatment with pSecTag2B-tum and gemcitabine significantly decreased tumor growth through increased inhibition of tumor angiogenesis and increased tumor cell apoptosis compared with either agent alone. Enhanced antiproliferative and proapoptotic activity of the combination therapy on tumor-associated endothelial cells was calculated to be significant. This study suggests that combined treatment by the intramuscular delivery of plasmid DNA encoding tumstatin and gemcitabine augments tumor growth inhibition by suppressing angiogenesis and enhancing apoptosis in murine models. A combination of these agents could be used in future studies and translated into the clinical setting.

Angiogenesis Inhibitors↗

PubMed2005

Qri2/Nse4, a component of the essential Smc5/6 DNA repair complex.

We demonstrate a role for Qri2 in the essential DNA repair function of the Smc5/6 complex in Saccharomyces cerevisiae. We generated temperature-sensitive (ts) mutants in QRI2 and characterized their properties. The mutants arrest after S phase and prior to mitosis. Furthermore, the arrest is dependant on the Rad24 checkpoint, and is also accompanied by phosphorylation of the Rad53 checkpoint effector kinase. The mutants also display genome instability and are sensitive to agents that damage DNA. Two-hybrid screens reveal a physical interaction between Qri2 and proteins that are non-Smc elements of the Smc5/6 DNA repair complex, which is why we propose the name NSE4 for the open reading frame previously known as QRI2. A key role for Nse4 in Smc5/6 function is likely, as overexpressing known subunits of the Smc5/6 complex suppresses nse4(ts) cell cycle arrest. The nse4(ts) growth arrest is non-lethal and unlike the catastrophic nuclear fragmentation phenotype of smc6(ts) mutants, the nucleus remains intact; replicative intermediates and sheared DNA are not detected. This could imply a role for Nse4 in maintenance of higher order chromosome structure.

Amino Acid Sequence↗

PubMed2005

Synthesis and evaluation of gadolinium complexes based on PAMAM as MRI contrast agents.

Diethylenetriaminepentaacetic acid (DTPA) and pyridoxamine (PM) were incorporated into the amine groups on the surface of ammonia-core poly(amidoamine) dendrimers (PAMAM, Generation 2.0-5.0) to obtain dendritic ligands. These dendritic ligands were reacted with gadolinium chloride to yield the corresponding dendritic gadolinium (Gd) complexes. The dendritic ligands and their gadolinium complexes were characterized by(1)HNMR, IR, UV and elemental analysis. Relaxivity studies showed that the dendritic gadolinium complexes possessed higher relaxation effectiveness compared with the clinically used Gd-DTPA. After administration of the dendritic gadolinium complexes (0.09 mmol kg(-1) ) to rats, magnetic resonance imaging of the liver indicated that the dendritic gadolinium complexes containing pyridoxamine groups enhanced the contrast of the MR images of the liver, provided prolonged intravascular duration and produced highly contrasted visualization of blood vessels.

Animals↗

PubMed2005

Simultaneous wavelength selection and outlier detection in multivariate regression of near-infrared spectra.

Near-infrared (NIR) spectrometry will present a more promising tool for quantitative measurement if the robustness and predictive ability of the partial least square (PLS) model are improved. In order to achieve the purpose, we present a new algorithm for simultaneous wavelength selection and outlier detection; at the same time, the problems of background and noise in multivariate calibration are also solved. The strategy is a combination of continuous wavelet transform (CWT) and modified iterative predictors and objects weighting PLS (mIPOW-PLS). CWT is performed as a pretreatment tool for eliminating background and noise synchronously; then, mIPOW-PLS is proposed to remove both the useless wavelengths and the multiple outliers in CWT domain. After pretreatment with CWT-mIPOW-PLS, a PLS model is built finally for prediction. The results indicate that the combination of CWT and mIPOW-PLS produces robust and parsimonious regression models with very few wavelengths.

Journal Article↗

PubMed2005

[Quantitative analysis of human globin gene expression in beta-thalassemia using real-time RT-PCR].

Whole blood samples were collected from 100 normal healthy adults, from umbilical cord of 33 newborn infants, 111 individuals with beta-thalassemia minor (beta(T)/beta(A),alphaalpha/alphaalpha) and 39 with beta-thalassemia major (beta(T)/beta(T),alphaalpha/alphaalpha). Prior to quantitative analysis of globin gene expression, DNA was extracted from all blood samples and used for beta-thalassemia genotype analysis. Different types of beta globin gene mutations were analyzed using reverse dot blotting (RDB) method. Total RNA were extracted and subjected to real-time RT-PCR for quantitative measurement of alpha, beta and gamma globin mRNA using three sets of primers and fluorescent-labeled probes, designed according to the sequences of alpha, beta and gamma human globin gene. Real-time RT-PCR was performed in ABI 7700 system. Following the real-time RT-PCR, the mean values of alpha, beta and gamma globin mRNA were calculated and the ratios of alpha/beta, alpha/(beta + gamma ) and gamma /(beta + gamma ) were determined to characterize the relative expression levels of different globin genes among normal adult, infant, beta-thalassemia minor and beta-thalassemia major patients. The resultant data were analyzed using SPSS 10.0 software to determine statistical significance of human globin gene expression among normal controls and beta-thalassemia patients. Due to vast variations of the mean globin gene mRNA levels among different groups, log conversion of alpha/beta + 1, alpha/(beta + gamma ) + 1 and gamma /(beta + gamma ) +1 was used for statistical analyses and intergroup comparison. The alpha/beta globin gene mRNA ratios were determined to be 4.62+/-1.20, 7.81+/-2.89, 13.51+/-5.12, and 188.24+/-374.04 for normal healthy adult (beta(A)/beta(A),alphaalpha/alphaalpha), infant (beta(A)/beta(A),alphaalpha/alphaalpha), beta- thalassemia minor (beta(T)/beta(A),alphaalpha/alphaalpha) and beta-thalassemia major(beta(T)/beta(T),alphaalpha/alphaalpha) respectively. The alpha/(beta+ gamma ) ratios were 4.43+/-1.17, 0.56+/-0.49, 9.62+/-4.37, and 2.14+/-1.58 for normal healthy adult (beta(A)/beta(A),alphaalpha/alphaalpha), infant (beta(A)/beta(A),alphaalpha/alphaalpha), beta- thalassemia minor (beta(T)/beta(A),alphaalpha/alphaalpha) and beta- thalassemia major(beta(T)/beta(T),alphaalpha/alphaalpha) respectively. The gamma /(beta+ gamma ) ratios were 0.04+/-0.03, 0.92+/-0.06, 0.28+/-0.18, and 0.95+/-0.04 for normal healthy adult (beta(A)/beta(A),alphaalpha/alphaalpha), infant (beta(A)/beta(A),alphaalpha/alphaalpha), beta- thalassemia minor (beta(T)/beta(A),alphaalpha/alphaalpha) and beta- thalassemia major (beta(T)/beta(T),alphaalpha/alphaalpha) respectively. Following statistical analyses, the alpha/beta and alpha/(beta+ gamma ) globin gene mRNA ratios were significantly different among four different groups (normal adult, normal infant, beta- thalassemia minor and beta- thalassemia major). The gamma /(beta + gamma ) globin gene mRNA ratio was significantly different among all groups except for between infant and beta- thalassemia major patients. Human beta globin gene mRNA levels decrease progressively and dramatically from normal adults to beta-thalassemia patients with beta-thalassemia major having the lowest levels. On the other hand, the gamma globin gene mRNA levels increase progressively from normal adult to beta-thalassemia patients with beta-thalassemia major having the highest levels. Infants have relatively lower levels of beta but higher levels of gamma globin gene mRNA as compared to those in normal adults. Thus, the relative expression levels of alpha, beta or gamma globin genes varied but inter-related among different ages of normal individuals and different beta-thalassemia genotypes.

Adult↗

PubMed2005

[Quantification of human ermap by using real-time FQ-PCR].

To develop a real-time FQ-PCR method for quantifying human ermap, a set of primers and a fluorescent probe were designed by primer express 2.0. pBluescriptSK(+) plasmid contained ermap cDNA was transcribed to generate calibration standards for quantification. A real time FQ-PCR method was established. The results showed that when the concentrations of DNA to be amplified were ranged from 1.725 x 10(7) to 1.725 x 10(10) cps/ml, there was a good correlation between template concentration and cycle threshold, and the correlation coefficient reached to -0.999376. In conclusion, real time FQ-PCR which is specific, sensitive and accurate can be used to further research on human ermap.

Blood Group Antigens↗

PubMed2005

[An experimental study on the influence of osteoporosis to bone repairing with bone matrix gelatin in ovariectomized rats].

OBJECTIVE: To study the influence of experimentally osteoporosis to osteogenic efficiency of bone matrix gelatin(BMG) implanted into the calvarial defects of rats. METHODS: Sixty-eight female SD rats of 12 +/- 1 weeks were randomly divided into two groups with 34 rats in each group. The ovaries were excised in the ovariectomized group (VG). The control group underwent sham surgery. Ninety days after ovariectomy, 10 rats from each group were examined to ensure the formation of postmenopausal osteoporosis by measuring bone density of the femur with single photon absorptiometric measurements. A critical-sized (8 mm in diameter) calvarial defect was created on the rest of 48 rats. Bone matrix gelatin was implanted to the defect. The rats were scarified at the 21st and 56th day after surgery respectively. The new bone forming capability of BMG was evaluated with undecalcified histological observation, tetracycline fluorescence marker, quantitative bone histomorphometry, At 90th day after ovariectomy, bone density of scanning electron microscopy and X-ray spectrometry. RESULTS: OVG showed very significant difference compared with the control group (0.315 +/-.015) g/cm2 vs [(0.347 +/- 0.017) g/cm2, P < 0.01 ]. At the 21st day following the implantation operation, new bone formed within the bone defects in both groups. The amount of new bone in OVG was lower than the control group. The tetracycline-labeled region in the bone defect was sparser in the OVG. At the 56th day, the bone defects healed mostly in the control group but fibrous tissue filled parts of bone defect in the OVG. The distance between two fluorescent lines of incorporated tetracycline and the mean mineralization deposition were significantly lower in the OVG than the control at the 21st day and 56th day. Mineralization of callus in OVG was inferior. Significant difference was found between the OVG and the control group in the calcium to phosphate ratio of callus in bone defects at the two time-points. CONCLUSIONS: Experimentally induced osteoporosis depressed osteogenic efficiency of BMG, suggesting that estrogen could play an important role in bone remodeling with bone substitute participating.

Animals↗

PubMed2005

[Analysis of multi-component sugar aqueous solution in low-concentration by near-infrared spectrometry].

Near infrared spectrophotometry was used to determine the concentrations of one, two and three-component sugar aqueous solutions. However, this method was always applied to dry or low moisture products and was not practicable for fresh fruits and vegetables because of the strong absorption of water in near infrared region. In this paper, the authors applied NIR method to aqueous solutions and discussed how to enhance the sensitivity. In aqueous solution systems, concentration of each individual sugar was in range of 0.01-0.25 mol x L(-1). Different calibrations and predicted results were gotten and compared to each other when full spectra or significant spectra regions were considered. By selecting relevant spectra regions due to important structural information to overcome the disturbance from absorption of water, calculations could be optimized and predicted results of concentrations were more accurate regarding the standard error of calibration (SEC) and standard error of prediction (SEP).

Calibration↗

PubMed2005

[Study on the adsorption behavior of Ga, In and Tl on nanometer-size titanium dioxide by ICP-AES].

The adsorption behavior of nanometer TiO2 towards Gallium (Ga) Indium (In) and Thallium (Tl) was investigated with inductively coupled plasma atomic emission spectrometry (ICP-AES). The optimum conditions for adsorption were studied in detail, and the test included sorption kinetics, effect of pH on adsorption ratio, enrichment factor, and adsorption capacity. Under the optimum conditions, Ga (III), In(III) and Tl(I) ions could be adsorbed and recovered quantitatively. The static adsorption capacities of Ga(III), In(III) and Tl(I) on nanometer TiO2 were 48.6, 46.6 and 23.4 mg x g(-1) respectively. For the elution of Ga(III), In (III) and Tl(I), a mixture of 0.1 mol x L(-1) EDTA solution and 1.0 mol x L(-1) HNO3 was used, and the recovery ratio was above 92%. According to the definition of IUPAC, the detection limits (3sigma) of this method for Ga, In and Tl with an enrichment factor of 12.5 are 3.0, 6.0 and 13 ng x mL(-1), respectively; and relative standard deviations (RSD) are 1.85%, 1.96% and 3.4%, respectively (n = 6). The proposed method has been applied successfully to the analysis of geological samples with satisfactory results.

Edetic Acid↗

PubMed2005

[Clinical study on analgesic effect of Huaisanzhen on the nerve root pain due to prolapse of lumbar intervertebral disc].

OBJECTIVE: To search for an effective therapy for the nerve root pain caused by prolapse of lumbar intervertebral disc. METHODS: One hundred and ninety-two cases were randomly divided into a Huaisanzhen group of 96 cases, a drug control group of 48 cases and an acupuncture control group of 48 cases. The Huaisanzhen group were treated by Huaisanzhen therapy, the drug control group by intramuscular injection of aspirin-DL-lysine and the acupuncture control group by routine acupuncture. RESULTS: The time inducing analgesic effect was shorter, the effect-lasting time was longer, and the analgesic effect and the comprehensive therapeutic effect were better in the treatment group as compared with the two control groups with very significant differences (P < 0.01). CONCLUSION: Huaisanzhen therapy has a better analgesic effect on the nerve root pain due to prolapse of lumbar intervertebral disc.

Analgesics↗

PubMed2005

[Detection of glucocorticoid receptor-alpha mRNA expression using FQ-RT-PCR in nasal polyp].

OBJECTIVE: To detect the expression of the glucocorticoid receptor-alpha (GR-alpha) mRNA in nasal polyp and normal nasal mucosa and investigate the significance of GR-alpha in progression of nasal polyp. METHOD: The expression of GR-alpha mRNA in 36 samples of nasal polyp and 31 samples of normal nasal mucosa was examined by using fluorescent quantitative PCR(FQ RT-PCR). RESULT: The GR-alpha mRNA levels in normal nasal mucosa [(135.4 +/- 5.2) x 10(10) copy/g] were significantly higher than those in nasal polyp [(25.5 +/- 5.0) x 10(10) copy/g] (P < 0.01). CONCLUSION: The low expression of GR-alpha mRNA in nasal polyp is related to the progression of nasal polyp.

Adult↗

PubMed2004

Cloud point extraction for speciation of chromium in water samples by electrothermal atomic absorption spectrometry.

A new method based on the cloud point extraction (CPE) separation and electrothermal atomic absorption spectrometry (ETAAS) detection was proposed for the determination of chromium species. When the system temperature is higher than the cloud point extraction temperature (CPT) of selected surfactant p-octyl polyethyleneglycolphenyether (Triton X-100), the complex of Cr(VI) with dibromophenylfluorone (Br-PF) could enter surfactant-rich phase, whereas the Cr(III) remained in aqueous phase. Thus, an in situ separation of Cr(VI) and Cr(III) could be realized. Cr(VI) in surfactant-rich phase was analyzed by ETAAS and Cr(III) was calculated by subtracting of Cr(VI) from the total chromium which was directly determined by ETAAS. The main factors affecting the cloud point extraction, such as pH, concentration of Br-PF and Triton X-100, equilibration temperature and time, were investigated systematically. Under the optimized conditions, the quantitation limit for Cr(VI) as low as 0.01 microg/L was obtained by preconcentrating a 10 mL sample solution, and the relative standard deviation (n=6, c=2.0 microg/L) was 2.6%. The proposed method was applied to the speciation of chromium in different water samples and the recoveries in the range of 98.9-105.3% were obtained by spiking the real samples. In order to verify the accuracy of the method, a certified reference water sample was analyzed and the results obtained were in good agreement with the certified values.

Cations↗

PubMed2004

Diallyl sulfide induces heme oxygenase-1 through MAPK pathway.

Diallyl sulfide (DAS), is protective against chemically induced heptotoxicity, mutagenesis, and carcinogenesis. The mechanism of its protective effects is not fully understood. In this study, we found that DAS can induce the expression of heme oxygenase-1 (HO-1), which plays a critical role in the cell defense system against oxidative stress. DAS causes a dose- and time-dependent increase of HO-1 protein and mRNA level without toxicity in HepG2 cells. DAS-induced HO-1 protein expression is dependent on newly synthesized mRNA and newly synthesized protein. DAS increases Nrf2 protein expression, nuclear translocation, and DNA-binding activity. The MAP kinase ERK is activated by DAS. Both ERK and p38 pathways play an important role in DAS-induced Nrf2 nuclear translocation and ho-1 gene activation. DAS stimulates a transient increase of reactive oxygen species (ROS). N-Acetyl-cysteine blocked this increase of ROS production as well as DAS-induced ERK activation, Nrf2 protein expression and nuclear translocation, and ho-1 gene activation. The increase in HO-1 produced by DAS protected the HepG2 cells against toxicity by hydrogen peroxide or arachidonic acid. These results suggest that DAS induces ho-1 through production of ROS, and Nrf2 and MAPK (ERK and p38) mediate this induction. Induction of ho-1 may play a role in the protective effects of DAS.

Allyl Compounds↗

PubMed2004

A new hybrid strategy for constructing a robust calibration model for near-infrared spectral analysis.

A new hybrid algorithm is proposed for construction of a high-quality calibration model for near-infrared (NIR) spectra that is robust against both spectral interference (including background and noise) and multiple outliers. The algorithm is a combination of continuous wavelet transform (CWT) and a modified iterative reweighted PLS (mIRPLS) procedure. In the proposed algorithm the spectral interference is filtered by CWT at the first stage then mIRPLS is proposed to detect the multiple outliers in the CWT domain. Compared with the original IRPLS method, mIRPLS does not need to adjust variable parameters to achieve optimum calibration results, which makes it very convenient to perform in practice. The final PLS model is constructed robustly because both the spectral interference and multiple outliers are eliminated. In order to validate the effectiveness and universality of the algorithm, it was applied to two different sets of NIR spectra. The results indicate that the proposed strategy can greatly enhance the robustness and predictive ability of NIR spectral analysis.

Journal Article↗

PubMed2004

Monocytes recruited to the lungs of mice during immune inflammation ingest apoptotic cells poorly.

Apoptotic cells must be cleared to resolve inflammation, but few resident alveolar macrophages (AMo) from normal lungs ingest apoptotic cells. We examined how Mo ingestion of apoptotic cells is altered during immune inflammation induced by intratracheal challenge of primed C57BL/6 mice using sheep red blood cells. Resident AMo were labeled in situ before challenge using intravenous PKH26 to distinguish them from recruited monocytes. Using flow cytometry, we identified phagocytosis of fluorescently-labeled apoptotic thymocytes by alveolar mononuclear phagocytes in vitro and in vivo, and measured surface molecule expression. Intratracheal challenge induced rapid recruitment of monocytes, peaking at Day 3 and decreasing thereafter, whereas numbers of resident AMo did not change significantly. At all times, the percentage of phagocytes ingesting apoptotic thymocytes in vitro was greater among resident AMo (28-45%) than among recruited monocytes (9-19%), but was low in both cell types relative to ingestion of immunoglobulin-opsonized targets. There was also a nonsignificant trend toward lower ingestion by monocytes in vivo. MerTK, a receptor tyrosine kinase crucial for apoptotic cell phagocytosis, was expressed by resident AMo, but not by recruited monocytes. Relative to resident AMo, monocytes recruited to the alveolus ingest apoptotic cells meagerly, possibly due to absence of MerTK expression.

Animals↗