Analysis of two single nucleotide polymorphisms and loss of heterozygosity detection in the VHL gene in Chinese patients with sporadic renal cell carcinoma.
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Adult↗
Biomedical subjects
Ning Liu
Publications and source records attributed to Ning Liu.
Gender related effects of heroin abuse on the simple reaction time task.
Accumulated studies have demonstrated that there are serious negative consequences of drug abuse, especially the impairment of central nervous system (CNS) function. The simple reaction time (SRT) is the simplest model of measuring the function of the CNS. The purpose of the present study is to examine whether the SRT is affected by heroin abuse and whether such drug effect, if exists, is gender related. We found significant slowing of the SRT in both male and female heroin dependent patients at 1-3 months from withdrawal. However, the SRT slowing remitted after 3 months of abstinence in heroin dependent males but not in females. Our results suggested that the SRT is slowed by heroin abuse and such slowing is gender related.
Adult↗
Vibronic spectroscopy of single C60 molecules and monolayers with the STM.
A scanning tunneling microscope is used to study the differential conductance (dI/dV) of single C(60) molecules in isolation and in monolayers adsorbed on NiAl(110) and on an ultrathin alumina film grown on the NiAl(110) surface. On the oxide layer, the electronic bands in the dI/dV spectra display a series of equally spaced features, attributed to the vibronic states of the molecules, which are absent when the molecules are adsorbed on the metal. A comparison between the molecular spectra measured on the oxide film reveals the effect of adsorption temperature and geometry, as well as intermolecular interactions on the vibronic features.
Journal Article↗
Age-related effects of bromocriptine on sensory gating in rhesus monkeys.
Declines in dopamine neurotransmission are a robust characteristic of the process of normal aging. Using neuroimaging, biochemical and cognitive methods, age-related reduction of D2 receptor has been noted in a wide range of species. On the other hand, it is well known that dopamine plays a crucial role in the modulation of sensory gating. Here, we examined age-related alterations of D2 receptor in rhesus monkeys, using a sensory gating paradigm. The direct D2 receptor agonist, bromocriptine, was characterized in young adult and aged monkeys. We found bromocriptine disrupted sensory gating in young adult monkeys but not in aged ones. Our results provided new evidence that there is a functional decline of D2 receptor in aged monkeys.
Aging↗
Bayesian non-response models for categorical data from small areas: an application to BMD and age.
We provide a Bayesian analysis of data categorized into two levels of age (younger than 50 years, at least 50 years) and three levels of bone mineral density (normal, osteopenia, osteoporosis) for white females at least 20 years old in the third National Health and Nutrition Examination Survey. For the sample, the age of each individual is known, but some individuals did not have their BMD measured. We use two types of models: In the ignorable non-response models the propensity to respond does not depend on BMD and age of an individual, while in the non-ignorable non-response models it does. These are the baseline models which are used to derive all models for testing. Our non-ignorable non-response models are 'close' to the ignorable non-response models, thereby reducing the effects of the assumptions about non-respondents that cannot be tested in non-response models. We have data from 35 counties, small areas, and therefore our models are hierarchical, a feature that allows a 'borrowing of strength' across the counties, and they provide a substantial reduction in variation. The non-ignorable non-response models are generalizations of the ignorable non-response models, and therefore, the non-ignorable non-response models allow broader inference. The joint posterior density of the parameters for each model is complex, and therefore, we fit each model using Markov chain Monte Carlo methods to obtain samples which are used to make inference about BMD and age. For each county we can estimate the proportion of individuals in each BMD and age cell of the categorical table, and we can assess the relation between BMD and age using the Bayes factor. A sensitivity analysis shows that there are differences (typically small) in inference that permits different levels of association between BMD and age. A simulation study shows that there is not much difference between the baseline ignorable and non-ignorable non-response models.
Adult↗
Suppressive mechanisms of Sairei-to on mesangial matrix expansion in rat mesangioproliferative glomerulonephritis.
BACKGROUND: Sairei-to (TJ-114) is a Japanese herbal medicine of standardized quality, originating from traditional Chinese medicine. In the present in vivo study, we investigated the suppressive effects of TJ-114 and related drugs, Shosaiko-to (TJ-9), and Saiboku-to (TJ-96), on mesangioproliferative glomerulonephritis (MsPGN) in rats. TJ-9 is a basal prescription of TJ-96 and TJ-114. We evaluated the efficacy of these drugs on proteinuria, extracellular matrix (ECM) accumulation, and superoxide dismutase (SOD)-activity. METHODS: MsPGN in Wistar rats was induced by intravenous injection of rabbit anti-rat thymocyte serum (ATS). TJ-114, TJ-9, TJ-96 (500 mg/kg/day), or prednisolone (PSL, 2 mg/kg/day) was orally administered to the rats as drinking water from the day of ATS injection (day 0) to day 8, when rats were sacrificed and the kidney specimens were collected. Macrophage infiltration was evaluated by immunostaining for ED-1. ECM was measured by trichrome-staining, and fibronectin immunostaining. Northern blotting was performed to clarify the mRNA expression of cytokines and fibronectin. SOD-activity in the homogenate of renal cortex was also evaluated. RESULTS: The amount of urinary protein was significantly decreased only in the TJ-114-treated group compared with the disease control group (p < 0.05). The number of ED-1-positive cells was significantly decreased in all the treatment groups (p < 0.05, respectively). Decreases in the trichrome-stained area were observed moderately in the TJ-114-treated group (66% of control, p < 0.001) and mildly in the PSL-treated group (76% of control, p < 0.001). The staining area of fibronectin in the glomerulus was significantly decreased in all the treated groups except PSL, and was especially suppressed in the TJ-114-treated group (45% of control, p < 0.001). Transforming growth factor (TGF) and connective tissue growth factor (CTGF) expression significantly decreased in the TJ-114-treated group to the control level (p < 0.05). TGF-beta, CTGF, and fibronectin mRNA were upregulated in the disease control group, and TJ-114 suppressed these mRNA expressions in glomeruli. The SOD-activity of renal cortex-homogenate was significantly augmented in all the treated groups except PSL, markedly in the TJ-96- and TJ-114-treated groups. CONCLUSION: These results suggest that TJ-114 ameliorates ECM accumulation in experimental rat MsPGN, partly suppressing TGF-beta and CTGF expression through the recovery of SOD-activity.
Animals↗
Expression, localization, and functional characteristics of breast cancer resistance protein in Caco-2 cells.
The function of breast cancer resistance protein (BCRP) and its role in drug absorption, distribution, and elimination has recently been evaluated. The objective of the present study was to examine the expression, localization, and functional characteristics of BCRP in Caco-2 cells, a widely used human intestinal epithelial cell model for investigating intestinal drug absorption. The expression of BCRP in Caco-2 cells was measured by Western blotting using the antibody BXP-21. Localization of BCRP was determined by an immunofluorescence technique using both antibodies BXP-21 and BXP-34. The drug efflux function of BCRP was evaluated via the epithelial transport of methotrexate (MTX) and estrone-3-sulfate (E3S) across Caco-2 cell monolayers in the presence or absence of the BCRP inhibitors Ko143 or GF120918 (N-(4-[2-(1,2,3,4-tetrahydro-6,7-dimethoxy-2-isoquinolinyl)ethyl]-phenyl)-9,10-dihydro-5-methoxy-9-oxo-4-acridine carboxamide). Results from Western blot assay indicated that Caco-2 cells in the late passage (p56) expressed a higher level of BCRP as compared with the level in the early passages (p33). The total amount of BCRP protein did not change after the cells were confluent. Immunofluorescence studies revealed the positive staining of BCRP on the apical membrane of Caco-2 cells but not on the basolateral membrane after cell confluence. MTX and E3S showed a preferential basolateral-toapical (B-to-A) transport across Caco-2 cell monolayers. Both BCRP inhibitors Ko143 and GF120918 increased the apical-to-basolateral (A-to-B) transport but decreased the B-to-A transport of MTX and E3S. Caco-2 cells may therefore be used as an in vitro model to study the transport characteristics of BCRP.
ATP Binding Cassette Transporter, Subfamily G, Mem↗
Enhancement of Schwann cell myelin formation by K252a in the Trembler-J mouse dorsal root ganglion explant culture.
The Trembler-J (TrJ) mouse, containing a point mutation in the peripheral myelin protein 22 gene, is characterized by severe hypomyelination and is a representative model of Charcot-Marie-Tooth 1A disease/Dejerine-Sottas Syndrome. Previous studies have shown that protein kinase inhibitor K252a enhances wild-type Schwann cell myelination in culture. We used a dorsal root ganglion (DRG) explant culture system from the heterozygous TrJ/+ mouse to investigate if myelination could be enhanced by K252a. The TrJ/+ DRG explant cultures replicated some important features of the TrJ/+ mouse, showing reduced myelin protein accumulation, thinner myelin sheaths, and shortened myelin internodes. K252a increased myelin protein accumulation and myelin sheath thickness but did not substantially increase myelin internode length. Furthermore, the TrJ/+ DRG explant culture and sciatic nerves continued to respond to K252a during the stage when myelination is complete in the wild type. A general tyrosine kinase inhibitor, genistein, but not inhibitors of serine/threonine protein kinase inhibitors, had a similar effect to K252a. K252a is therefore able to partially overcome hypomyelination by enhancing mutant Schwann cell myelin formation in the TrJ/+ mouse.
Animals↗
Three-element phased-array approach to diffuse optical imaging based on postprocessing of continuous-wave data.
We present a multielement phased-array approach to diffuse optical imaging based on postprocessing of continuous-wave data for the improvement of spatial resolution. In particular, we present a theoretical and experimental analysis of the performance of a three-element source array in the study of an optically turbid medium with two embedded cylindrical inclusions. We find that the proposed phased-array approach is able to resolve two cylinders with side-to-side separation of 10 mm that are not resolved by the intensity associated with a single light source.
Image Enhancement↗
[Analysis of biallelic inactivation of the von Hippel-Lindau tumor suppressor gene VHL in patients of renal cell carcinoma patient].
OBJECTIVE: To investigate biallelic inactivation of the von Hippel-Lindau tumor suppressor gene (VHL) in patient of renal cell carcinoma (RCC) patient. METHODS: We extracted tumor and normal DNA from 41 RCC patients. Mutation of VHL gene from tumor tissue was detected from tumor tissue by polymerase chain reaction (PCR) and direct sequencing. Two single nucleotide polymorphism (SNP) sites located in VHL gene were analyzed by PCR restriction fragment length polymorphism, and loss of heterozygosity (LOH) was analyzed for VHL gene by comparing between tumor with normal tissue. RESULTS: Mutation and LOH of VHL gene was found in 51% (21/41) and 42% (8/19) of RCC patients respectively. LOH was highly associated with mutation positive tumors (r = 0.78) and VHL biallelic inactivation was detected in 37% of RCC patients. CONCLUSION: Biallelic inactivation of VHL gene occurs in RCC due to VHL mutation and LOH, and its frequency rate is 37%.
Adult↗
Calcium antagonistic effects of Chinese crude drugs: preliminary investigation and evaluation by 45 Ca.
Coronary and other diseases in cardiac or brain blood vessels are considered to be due to the excessive influx of Ca(2+) into cytoplasm. If Ca(2+) channels in cell membrane are blocked by medicines or other substances with considerable calcium antagonistic effects, these diseases might be cured or controlled. The influence of some Chinese crude drugs, including Crocus sativus, Carthamus tinctorius, Ginkgo biloba and Bulbus allii macrostemi on Ca(2+) influx in isolated rat aortas was investigated by using (45)Ca as a radioactive tracer, and their calcium antagonistic effects were evaluated. It can be noted that Ca(2+) uptake in isolated rat aorta rings in normal physiological status was not markedly altered by these drugs, whereas the Ca(2+) influxes induced by norepinephrine of 1.2 micromol/L and KCl of 100 mmol/L were significantly inhibited by Crocus, Carthamus and Bulbus in a concentration-dependent manner, but not by Ginkgo. The results show that extracellular Ca(2+) influx through receptor-operated Ca(2+)channels and potential-dependent Ca(2+)channels can be blocked by Crocus, Carthamus and Bulbus. This implies that these Chinese crude drugs have obvious calcium antagonistic effects.
Animals↗
High level expression, purification, and characterization of the shrimp antimicrobial peptide, Ch-penaeidin, in Pichia pastoris.
Penaeidins, members of a new family of antimicrobial peptides constitutively produced and stored in the haemocytes of penaeid shrimp, display antimicrobial activity against bacteria, and fungi. Here, a DNA sequence encoding the mature Ch-penaeidin peptide was cloned into the pPIC9K vector and transformed into Pichia pastoris. The transformed cells were screened for multi-copy plasmids using increasing concentrations of G418. Positive colonies carrying chromosomal integrations of the Chp gene were identified by phenotype and PCR. When transformed cells were induced with methanol, SDS-PAGE and Western blotting revealed the production of a approximately 6100 Da recombinant CHP (rCHP) expression product. Large scale expression revealed that rCHP was produced at 108 mg/L under optimal conditions in the highest Chp-producing P. pastoris clone. The antimicrobial activities of rCHP were studied by liquid phase analysis, which revealed that rCHP exhibited activities against some Gram-negative and Gram-positive bacteria, but had a relatively low activity against some fungi. Purification of rCHP by cation exchange chromatography and subsequent automated amino acid sequencing revealed the presence of four additional amino acids (YVEF) at the N-terminus that belonged to the cleaved fusion signal peptide; these residues may account for the observed decrease in antifungal activity. Together, these observations indicate that rCHP is an effective antimicrobial peptide that can be successfully produced at high levels in the yeast, and therefore may be a potential antimicrobial candidate for practical use.
Amino Acid Sequence↗
Tuning the bipolar conductance of an alkali-doped C(60) layer sandwiched between two tunneling barriers.
Resonant tunneling through a C(60) monolayer doped with single Na, K, Rb, and Cs atoms was measured between the tip of a scanning tunneling microscope and a NiAl(110) substrate. By supporting the monolayer on a thin aluminum oxide film grown on the substrate, a double barrier tunnel junction is formed, consisting of the vacuum and oxide. This geometry enables conductance through an electronic state of the alkali-C(60) complex at both positive and negative sample bias. The positions of the conductance peaks can be varied by tuning the vacuum barrier. An opposite variation is found for Na and K as compared to Rb and Cs, suggesting the influence of bonding on nanoscale transport.
Journal Article↗
Role of coagulation factor Xa and protease-activated receptor 2 in human mesangial cell proliferation.
BACKGROUND: Fibrin deposition and mesangial cell proliferation are frequently observed in the active type of mesangioproliferative glomerulonephritis. Coagulation factors, such as factor V and factor Xa are colocalized with fibrin in the mesangial areas in active type of IgA nephropathy with mesangial cell proliferation. In this study, therefore, we studied the role of factor Xa and its receptor, protease-activated receptor 2 (PAR2) in mesangial cell proliferation and fibrin deposition, and examined ant-proliferative effects of a specific factor Xa inhibitor, DX-9065a, in cultured human mesangial cells. METHODS: To examine the effect of DX-9065a on the factor Xa-induced proliferation of cultured human mesangial cells, we measured thymidine incorporation and cell numbers. We also examined the effect of DX-9065a on extracellular regulated kinase (ERK) activation and fibrin production induced by factor Xa in human mesangial cells. RESULTS: Factor Xa increased [(3)H]-thymidine incorporation and cell numbers in a dose-dependent manner in mesangial cells, which was inhibited by DX-9065a. DX-9065a also suppressed factor Xa-triggered fibrin deposition on mesangial cell surface. Factor Xa induced the activation of ERK in mesangial cells and this activation was also completely inhibited by DX-9065a, but not inhibited by PAR1 antagonist. Factor Xa-induced cell proliferation and ERK activation were inhibited by PD98059. CONCLUSION: There results suggest that factor Xa can induce mesangial cell proliferation through the activation of ERK via PAR2 in mesangial cells and that PAR2 may play a crucial role in the cell proliferation induced by factor Xa. Our results implicate that DX-9065a may be a promising agent to regulate proliferation of mesangial cellss and inhibit the coagulation process in mesangium.
Benzamides↗
Spatial and spectral information in optical mammography.
This article reviews our research activities in the area of optical mammography and relates them to the historical developments and the current state and trends in the field. The guiding threads for this article are the roles played in optical mammography by spatial and spectral information. The first feature, spatial information, is limited by the diffusive nature of light propagation but can take advantage of the exceptionally high optical contrast featured by blood vessels and blood-rich areas in the breast. We describe a method to correct for edge effects, a spatial second-derivative algorithm, and a two-dimensional phased-array approach that enhance the image contrast, the spatial resolution, and the depth discrimination in optical mammograms. The second feature, spectral information, is the most powerful and unique capability of optical mammography, and allows for functional measurements associated with hemoglobin concentration and oxygenation, water concentration, lipids content, and the wavelength dependence of tissue scattering. We present oxygenation-index images obtained from multi-wavelength optical data that point to the diagnostic potential of oxygenation information in optical mammography. The optimization of the spatial and spectral information in optical mammography has the potential to create a role for this imaging modality in the detection and monitoring of breast cancer.
Breast Neoplasms↗
[Analysis of two single nucleotide polymorphisms in von Hippel-Lindau gene and detection of loss of heterozygosity in Chinese sporadic renal cell carcinoma].
OBJECTIVE: To exam two single nucleotide polymorphism(SNP) in VHL gene and intragenic loss of heterozygosity (LOH) of VHL gene in 79 Chinese sporadic renal cell carcinomas(RCCs), and to analyze the relationships between VHL LOH and clinicopathological parameters. METHODS: The authors extracted tumor and normal tissue DNA and detected two genotypes of intragenic SNP sites, rs779805 in the 5'terminal and rs 1642742 in the 3'terminal of VHL gene by polymerase chain reaction-restriction frament length polymorphism, then analyzed VHL LOH by comparing tumor tissue versus normal tissue in heterozygosities. Subsequently the relationships between VHL LOH and clinicopathological parameters of RCCs were analyzed. RESULTS: The computed heritage parameters of two SNPs, included genotype frequency, allele frequency, heterozygosity, and polymorphism information content. Twenty-nine heterozygosities were detected in 79 RCCs. LOH was found in 41.4%(12/29) of RCCs. No significant relationships between VHL LOH and age, sex, tumor stage, pathological grade were found. CONCLUSION: LOH of VHL gene is an important genetic event in Chinese sporadic renal carcinoma, and the LOH frequency is 41.4%. VHL LOH has no influence on stage and grade of RCC.
Adult↗
[The effect of nandrolone phenylpropionate on fibroblasts after injury in rats].
OBJECTIVE: To explore the effect of nandrolone phenylpropionate (NP) on rats' fibroblasts after injury. METHODS: After being isolated from granulation tissue of a one-month Wistar rat,the fibroblasts(FB) were grouped into 5 groups and cultured in RPMI1640 and 5% FBS culturing liquid with 0.5, 1.0, 5.0, 10.0, and 15.0 microg/ml NP respectively. The control group was cultured in RPMI1640 and 5% FBS culturing liquid Fibroblasts were isolated from granulation tissue of a one-month Wistar rat and cultured with RPMI1640 culturing liquid with 5% FBS added different doses of NP from 0.5 approximately 15.0 microg/ml in NP group, but only 5% FBS for the control group. Cell validity of fibroblasts was measured by MTT. The proliferative index (PI) of the most effected group was measured by flow cytometry. RESULTS: Compared with control group, higher FB validity occurred in every NP group (P < 0.05) The PI of FB in every NP group measured by flow cytometry was significantly higher than that in control group (P < 0.01). CONCLUSION: NP can promote the replication and proliferation of FB.
Anabolic Agents↗
[Expression of androgen receptor on fibroblast and hepatocyte of rats after deep second-degree burn caused by scalding].
OBJECTIVE: To investigate the effect of protein anabolic hormone on fibroblast and hepatocyte of rat and the mechanism therein involved. METHODS: Thirty-two Wistar rats with deep second-degree scald injury of 20% total body surface area (TBSA) were randomly divided into two groups to receive either 5 mg/kg of an anabolic steroid--nandrolone phenylpropionate (NP group) or normal saline as placebo (control group) every other day. Mean Integrated Optical Density (mIOD) of androgen receptor (AR) in fibroblast and hepatocyte of rats were measured by immunohistochemistry individually on the post-burn days 4, 7, 14 and 21. RESULTS: The expression levels of AR on fibroblast and hepatocyte in NP group were significantly higher than those in the control group respectively. CONCLUSION: Nandrolone phenylpropionate can enhance the expression and activation of AR on fibroblast and hepatocyte.
Animals↗