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Ying Hu

Publications and source records attributed to Ying Hu.

At least 55 records · Page 3Linked to original sources
PubMed2006

Multidetector-row computed tomography in the management of hepatocellular carcinoma with transcatheter arterial chemoembolization.

With the introduction of spiral computed tomography and the development of novel imaging technology in recent years, multidetector-row computed tomography (MDCT) has increasingly been used for the diagnosis of various lesions, especially hepatocellular carcinoma (HCC), due to its volume acquisitions, short scanning time, and especially its double-phase scanning nature, which takes advantage of the dual blood supply of liver. Multidetector-row computed tomography is used to classify HCC into several types based on the blood supply and the histological characteristics of HCC. The evaluation of HCC by MDCT provides crucial clues for the doctors to adopt correct clinical management strategies such as the selection of the appropriate dose of lipiodol before transcatheter arterial chemoembolization (TACE) and the prediction of the prognosis of HCC after TACE. The MDCT scanning allows doctors to choose the region of interest and to evaluate the blood supply according to the lipiodol uptake in order to decide whether there is recrudescence and whether a repeated therapy should be taken. This review describes MDCT, its biphasic scanning, its evaluation of blood supply in HCC and the subsequent classification of HCC, its therapeutic significance before TACE and the prognostic value after TACE.

Carcinoma, Hepatocellular↗
PubMed2006

Delineation of diversified desmoglein distribution in stratified squamous epithelia: implications in diseases.

Desmogleins play critical roles in cell adhesion and skin blistering diseases, as they are the target antigens of autoimmune antibodies and bacterial toxins. We recently cloned several novel members of the desmoglein gene family, bringing the number of desmogleins to four in the rat and human genomes and six in the mouse. Here, we have produced a monoclonal antibody to a cytoplasmic epitope of Dsg4, assessed its specificity and compared it to several existing Dsg1-3 antibodies. We also demonstrated cross-reactivity of commercially available and often used Dsg1 antibodies. Using these tools, we delineated the unique expression patterns of each desmoglein isoform in various human and mouse stratified squamous epithelia, including skin, hair, palm, and oral mucosa. Interestingly, in the epidermis, the expression of each desmoglein correlates with their gene arrangement in the cadherin locus. In human, Dsg4 was detected primarily in the granular and cornified cell layers of the epidermis, while present throughout all differentiated layers of the oral mucosa and palm, and in the matrix cells of anagen hair bulb. Similar pattern of expression for Dsg4 was observed in mouse, with the exception that it was expressed at significantly lower levels in the mouse epidermis. These results demonstrate the complexity of desmoglein gene expression and provide additional insights into the correlation between tissue expression patterns and disease phenotypes.

Adult↗
PubMed2006

Temperature-jump apparatus with Raman detection based on a solid-state tunable (1.80-2.05 microm) kHz optical parametric oscillator laser.

The operating characteristics of a pulsed (10 ns) tunable near-infrared (NIR) laser source are described for temperature-jump (T-jump) applications. A Q-switched Nd:YLF laser (approximately 10 ns pulses) with a 1 kHz repetition rate is used to pump a potassium titanyl arsenate (KTA) crystal-based optical parametric oscillator (OPO), producing approximately 1 mJ NIR pulses that are tunable (1.80-2.05 microm) across the 1.9 microm vibrational overtone band of water. This T-jump source has been coupled to a deep ultraviolet (UV) probe laser for Raman studies of protein dynamics. T-jumps of up to 30 degrees C, as measured via the O-H stretching Raman band of water, are readily achieved. Application to cytochrome c unfolding is demonstrated.

Animals↗
PubMed2006

Expression of p53, p16 and COX-2 in pancreatic cancer with tissue microarray.

BACKGROUND: Pancreatic cancer development and progression is driven by the accumulation of genetic changes. In this study we constructed tissue microarray containing specimens from pancreatic cancer, adjacent non-cancer tissue and normal tissue to survey the expression of p53, p16 and cyclooxygenase-2 (COX-2). METHODS: Tissue microarray containing 337 specimens from different stages of pancreatic cancer, adjacent non-cancer tissue and normal tissues was constructed, and the expression of p53, p16 and COX-2 was assayed by immunohistochemistry to consecutive formalin-fixed tissue microarray sections. RESULTS: The expression of p53, p16 and COX-2 was significantly higher in tumorous tissues than in non-tumorous ones. A significant relationship was observed between p53 and COX-2, or p16 and COX-2. But no obvious correlation was seen between p53 and p16 expressions. Logistic regression analysis showed p53 and COX-2 as dependent predictors in pancreatic carcinogenesis, and a reciprocal relationship to neoplastic progression between p53 and COX-2. CONCLUSION: Combination analysis of p53 and COX-2 may be useful in predicting pancreatic carcinogenesis.

Adolescent↗
PubMed2006

[Applications of terahertz pulse in the DNA molecule].

Terahertz (THz) radiation is a newly developed coherent far infrared source, which has been applied in many research fields, especially medical application and biological application. In the present paper, the mechanism and methods of its generation and detection are introduced. The properties and its uniqueness in applications to biological researches and DNA molecular spectroscopy are discussed. A brief review is given to the latest progress in THz spectroscopy of DNA samples, and the prospect of the research in this cross-discipline is presented.

Animals↗
PubMed2006

[Distribution of ion channels in pulmonary arterial smooth muscle cells and their roles in hypoxia pulmonary vasoconstriction].

Hypoxic pulmonary vasoconstriction (HPV) is the rapid, reversible increase in pulmonary vascular resistance that occurs when the alveolar oxygen tension falls below a threshold level, thereby achieving ventilation/perfusion matching. HPV is closely related to the state of K+, Ca2+ and Cl- channels in pulmonary arterial smooth muscle cells, which distribute heterogeneously along the longitude of pulmonary artery tree, and cause heterogeneous vasoconstriction response in different part of pulmonary artery in HPV. In this review we summarize current knowledge about the distribution of these ion channels and their roles in HPV.

Animals↗
PubMed2006

[Terahertz time-domain spectroscopic study of carbon monoxide].

Terahertz time-domain spectroscopy is a new coherent spectral technique based on femtosecond laser technology. The radiation band belongs to far infrared. This paper presents the absorption spectra of carbon monoxide measured by terahertz time-domain spectroscopy in the frequency range between 0.2 and 2.5 THz. The experimental results indicate that the carbon monoxide has many distinct characteristic spectra between 0.2 and 2.5 THz which agree with the calculated results. The absorption peaks become sharper with decreasing the pressure. This work establishes the basic spectra data for the future identification and characterization of carbon monoxide, and it is very significative to measure the harmful substance in the atmosphere by terahertz technology.

English Abstract↗
PubMed2006

[Expression of tissue microarray p53, p16 and cyclooxygenase-2 in gastric cancer].

OBJECTIVE: To constructed tissue microarray containing specimens from gastric cancer and adjacent non-cancer tissue to survey the expression of p53, p16 and cyclooxygenase-2 (COX-2), and to obtain a comprehensive survey on the expression of three proteins in gastric cancer progression and their clinical significance. METHODS: We constructed a tissue microarray containing 50 specimens from gastric cancer and 78 specimens from adjacent non-cancer tissue, and assayed three different proteins (p53, p16 and COX-2) by immunohistochemistry to consecutive formalin-fixed tissue microarray sections. RESULTS: In non-cancer tissue, p53, p16 and COX-2 positive staining were 19%, 15% and 74% respectively. In gastric cancer tissue, p53, p16 and COX-2 positive staining were 50%, 54% and 94% respectively. There were a significant difference between two different tissues (P < 0.05). 52% (66/128) cases were COX-2+/p53-, only 1 case were COX-2-/p53+. There was a significant association between COX-2 and p53 (P < 0.05). COX-2 negative expression tissues were found significantly more often in p53-negative than in p53-positive cases. 52% (67/128) cases were COX-2+/p16-, only 1 case were COX-2-/p16+. A significant correlation was recognized between expression of COX-2 and p16 (P < 0.05). Logistic regression analysis revealed that the risk factors of tumorous histotype were p53, p16 and COX-2 positive expression together, determined by Wald chi2 test (P < 0.05; odds ratio, 18.889). There was reciprocal relationship among p53, p16 and COX-2. CONCLUSION: Combination analysis of p53, p16 and COX-2 may be useful for the prediction of gastric carcinogenesis.

Adult↗
PubMed2006

[Management in squamous cell carcinoma of maxillary sinus with orbital invasion].

OBJECTIVE: To explore the orbital management in advanced squamous cell carcinoma of maxillary sinus with orbital invasion. METHOD: Forty-six postoperative cases of advanced squamous cell carcinoma of maxillary sinus with orbital invasion were followed up. Two,three,five-year survival rates and 2-year recurrence rates were analysed in,orbital bone invaded group, periorbit invaded group and orbital content invaded group. RESULT: Two, three,five-year survival rates and 2-year recurrence rates were 65.2%, 55.6%, 46.7% and 38.1% in orbital bone invaded group; 57.1%, 50.0%, 45.5% and 53.8% in periorbit invaded group; 44. 4%, 37. 5%, 37. 5% and 62. 5% in orbital content invaded group, respectively. Survival rates of three groups descended and recurrence rates of three groups ascended but without statistical significance( P >0. 05). CONCLUSION: During the surgery for advanced squamous cell carcinoma of maxillary sinus with orbital invasion without the evidence of optical nerve and eye ball involvement, preservation of orbital contents is considerable even though the orbital bone and periorbit are involved by the tumor.

Adult↗
PubMed2005

Density and chain conformation profiles of square-well chains confined in a slit by density-functional theory.

Density and chain conformation profiles of square-well chains between two parallel walls were studied by using density-functional theory. The free energy of square-well chains is separated into two contributions: the hard-sphere repulsion and the attraction. The Heaviside function is used as the weighting function for both of the two parts. The equation of state of Hu et al. is used to calculate the excess free energy of the repulsive part. The equation of state of statistical associating fluid theory for chain molecules with attractive potentials of variable range [A. Gil-Villegas et al. J. Chem. Phys. 106, 4168 (1997)] is used to calculate the excess free energy of the attractive part. Because the wall is inaccessible to a mass center of a longer chain, there exists a sharp fall in the distribution of end-to-end distance near the wall as the chain length increases. When the average density of the system is not too low, the prediction of this work is in good agreement with computer simulation results for the density profiles and the chain conformation over a wide range of chain length, temperature, and attraction strength of the walls. However, when the average density and the temperature are very low, the prediction deviates to a certain degree from the computer simulation results for molecules with long chain length. A more accurate functional approximation is needed.

Journal Article↗
PubMed2005

Sulindac corrects defective apoptosis and suppresses azoxymethane-induced colonic oncogenesis in p53 knockout mice.

The acute apoptotic response to genotoxic carcinogens (AARGC) might be important for controlling the subsequent colonic mutational load and progression through oncogenesis. We have found previously that AARGC is p53-dependent with a gene-dosage effect, and that decreased AARGC in p53(+/-) and p53(-/-) mice is associated with increased susceptibility to carcinogen-induced oncogenesis. We tested the ability of sulindac to reverse these defects. The effect of sulindac on azoxymethane (AOM)-induced apoptosis was measured in colonic epithelium in wild-type, p53(+/-) and p53(-/-) mice, 8 hr after a single AOM injection. Sulindac supplementation (0.5 +/- 0.1 mg/day) restored defective AARGC in p53(+/-) but not in p53(-/-) mice. For effect on colon tumor development, sulindac treatment was started at age 4 weeks in wild-type, p53(+/-) and p53(-/-) mice; three weekly AOM injections were commenced at 6 weeks of age to induce tumors. Sulindac reduced significantly tumor incidence and multiplicity in wild-type mice (17% and 0.3 tumors/mouse compared to 36% and 0.8 respectively without drug), in p53(+/-)mice (38% and 0.8 compared to 64% and 1.63) and in p53(-/-) mice (63% and 1.0 compared to 90% and 1.74). Although loss of p53 function impairs the apoptotic response to AOM-induced DNA damage, sulindac is capable of partly restoring this defect. As sulindac also reverses the increased risk of oncogenesis due to p53 dysfunction, its enhancement of the apoptotic response to initiating mutations might act to reduce mutational load driving oncogenesis. Sulindac is an effective chemopreventive agent in the presence of p53 dysfunction.

Animals↗
PubMed2005

Nanografting de novo proteins onto gold surfaces.

The immobilization of novel proteins onto addressable locations on a flat surface has potential applications in a range of biotechnologies. Here we describe the nanopatterning of a de novo protein onto a gold surface. Patterning was achieved using a technique called nanografting, in which the tip of an atomic force microscope is used to disrupt a preexisting monolayer of alkanethiol molecules on a gold surface, thereby facilitating exchange with alternative thiol-linked molecules from the surrounding solution. The protein used for these studies was chosen from a designed combinatorial library of de novo sequences expressed in E. coli and was engineered to have a glycine-glycine-cysteine tag at its C-terminus, thereby enabling attachment to the gold surface through a single cysteine thiol. The average height of the grafted protein patterns was found to be somewhat higher than expected from the known NMR structure of the protein. Compression of the nanografted patches by an external force (below 10 nN) was reversible but showed some hysteresis. Interestingly, both the energy required to deform the immobilized protein patterns and the energy defined by the hysteresis loop were found to be of the same order as the energy required to unfold the monomeric protein in solution. These studies demonstrate the possibility of preparing nanometer scale protein arrays, lowering significantly the volume requirements of the protein samples necessary to fabricate protein-based biosensor arrays and thereby providing a base for increasing their sensitivity.

Adsorption↗
PubMed2005

Interfacial tension in phase-separated aqueous cationic/anionic surfactant mixtures.

Interfacial tensions in two aqueous phase-separated cationic/anionic surfactant mixtures, CTAB/AS and 12-3-12/AS, without and with NaBr added were determined by the spinning drop method at 318.15 K. CTAB, 12-3-12 and AS are the abbreviations for cetyltrimethylammonium bromide, 1,3-propanediyl-bis(dodecyldimethylammonium bromide) and sodium dodecyl sulfonate, respectively. The interfacial tension sigma was found to be in the range of 0.06-21 microNm(-1). Toward a better understanding of the influence of the concentration difference between the separated phases in aqueous two-phase systems (ATPS) to interfacial tension, compositions of equilibrium phases were determined by elemental analysis coupled with material balance and electroneutrality. The investigation indicates that the concentration differences of surfactant ions between the separated phases and the adsorption of surfactant ions at the interface are the decisive factors determining the magnitude of interfacial tension.

Journal Article↗
PubMed2005

Absence of acute apoptotic response to genotoxic carcinogens in p53-deficient mice is associated with increased susceptibility to azoxymethane-induced colon tumours.

Acute apoptotic response to genotoxic carcinogens (AARGC) might be important for controlling the consequences of mutational load in the colon. It has been shown to occur in parallel with activation of DNA repair mechanisms. Inadequate AARGC might allow development of mutated clones with the potential to progress to cancer. In this study, we tested if p53 levels were important for AARGC in the colon and whether defective AARGC was associated with increased risk for colorectal oncogenesis. Apoptosis was measured in colonic epithelium of mice from each p53 genotype (p53-/-, p53+/-, wild-type) without and 8 hr following a single injection of azoxymethane (AOM). To determine risk for carcinogen-induced colorectal cancer (CRC), groups of mice from each p53 genotype received 3 weekly injections of AOM and colons were examined for tumour 20 weeks later. Rates of spontaneous apoptosis in colon were not affected by p53 level. However, AARGC was absent in p53-/- mice and reduced by 50% in p53+/- mice (both p < 0.01) compared to wild-type mice. AOM induced tumours in 30% of wild-type mice (average multiplicity 1.0 tumours/mouse) compared to 72% of p53+/- mice (2.0 tumours/mouse, p < 0.01) and 100% of p53-/- mice (2.8 tumours/mouse, p < 0.01). Without AOM, significantly fewer mice in all groups had tumours. Rates of apoptosis in tumours were independent of p53 status. p53 dysfunction puts intestinal epithelia at increased risk of genotoxin-induced oncogenesis due to impairment of apoptotic response mechanisms. p53 levels do not appear, however, to be important for spontaneous apoptosis in normal epithelium or apoptosis in tumours. Subsequent studies are now warranted to test the converse, namely, that enhanced apoptotic response to carcinogen reduces risk for colorectal oncogenesis.

Animals↗
PubMed2005

[Selective heterologous communication among human lung epithelial cells, fibroblasts, and lung cancer PG cells].

OBJECTIVE: To further understand the roles of gap junctional intercellular communication in carcinogenesis and progression of human lung cancer. METHODS: The heterologous communication was characterized among human lung epithelial cells HLEC, human lung fibroblasts HLF, human lung giant carcinoma PG cells and its Cx43 transfectants PG/C4 by using a preloading assay. Cx43 immunofluorescent staining and Northern blot were performed to examine Cx43 gene expression. RESULTS: Although both human lung fibroblasts HLF and epithelial cells HLEC expressed Cx43 and had very strong homologous communication, HLEC cells were unable to communicate with HLF cells. The human lung carcinoma cell line PG was defective of both homologous communication, and heterologous communication with its epithelial origin HLEC. Transfection of Cx43 into PG cells, which rescued PG cells' homologous communication and enhanced heterologous communication with HLF cells, could restore heterologous coupling with HLEC cells. CONCLUSION: Selective heterologous communication exists among different kinds of human lung cells, when human lung carcinoma cells lost coupling with its epithelial origin, Cx43 gene expression is not enough to establish heterologous communication between them.

Cell Communication↗
PubMed2005

Effects of hyperthyroidism on delayed rectifier K+ currents in left and right murine atria.

Hyperthyroidism has been associated with atrial fibrillation (AF); however, hyperthyroidism-induced ion channel changes that may predispose to AF have not been fully elucidated. To understand the electrophysiological changes that occur in left and right atria with hyperthyroidism, the patch-clamp technique was used to compare action potential duration (APD) and whole cell currents in myocytes from left and right atria from both control and hyperthyroid mice. Additionally, RNase protection assays and immunoblotting were performed to evaluate the mRNA and protein expression levels of K(+) channel alpha-subunits in left and right atria. The results showed that 1) in control mice, the APD was shorter and the ultra-rapid delayed rectifier K(+) conductance (I(Kur)) and the sustained delayed rectifier K(+) conductance (I(ss)) were larger in the left than in the right atrium; also, mRNA and protein expression levels of Kv1.5 and Kv2.1 were higher in the left atrium; 2) in hyperthyroid mice, the APD was shortened and I(Kur) and I(ss) were increased in both left and right atrial myocytes, and the protein expression levels of Kv1.5 and Kv2.1 were increased significantly in both atria; and 3) the influence of hyperthyroidism on APD and delayed rectifier K(+) currents was more prominent in right than in left atrium, which minimized the interatrial APD difference. In conclusion, hyperthyroidism resulted in more significant APD shortening and greater delayed rectifier K(+) current increases in the right vs. the left atrium, which can contribute to the propensity for atrial arrhythmia in hyperthyroid heart.

Action Potentials↗
PubMed2005

Effects of simvastatin on oxidative stress in streptozotocin-induced diabetic rats: a role for glomeruli protection.

AIMS: To study the effects of simvastatin on oxidative stress in rats with early stage diabetic nephropathy. METHODS: 60 male Sprague-Dawley rats were divided into three groups: control group (CN), streptozotocin (STZ)-induced diabetic rats group (DM) and STZ-induced diabetic rats group treated with simvastatin (DM+S). The following parameters were measured at weeks 6 and 12 in similar rats chosen randomly from each group: body and kidney weight, 24-hour urinary albumin excretion (UAE), biochemical indexes including blood glucose (GLU), low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TG), serum creatinine (SCr), antioxidant enzymes including superoxide dismutase (SOD), glutathione S-transferase (GST), catalase (CAT) in plasma, lipid peroxidation production as malondialdehyde in plasma (MDAp) and erythrocytes (MDAe), morphology parameters such as glomerular volume (GV) and mesangial area/total glomerular area (M/T). RESULTS: At weeks 6 and 12, GLU and kidney weight to body weight ratio were notably increased in both of the diabetic groups compared with those in the CN group without significant differences between the two diabetic groups. There were no significant differences of SCr, LDL, HDL and TG among all groups within all the experimental time. MDAp and MDAe were significantly increased in both of the diabetic groups, especially at week 12, while SOD, GST and CAT were significantly decreased compared with those in the CN group. At week 12, GV, M/T and UAE were also increased in the two diabetic groups. However, in the DM+S group, changes of lipid peroxidation production, antioxidant enzymes, UAE and GV were less pronounced than those in the DM group. Pearson's correlation analysis and regression analysis shown that MDAp was increased while SOD, GST and CAT in plasma were decreased with elevation of UAE, GV and M/T. CONCLUSION: Increased lipid peroxidation and decreased antioxidant enzymes in plasma may play a role in the progression of diabetic nephropathy. Simvastatin may ameliorate these changes to protect kidney from oxidative lesion in diabetes even in the absence of lipid abnormalities.

Albuminuria↗