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Hui Zhao

Publications and source records attributed to Hui Zhao.

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

[Adenoidectomy under indirectly visualization with laryngoscope].

OBJECTIVE: To describe the easy-performed, cost-effective adenoidectomy under indirect laryngoscope visualization. METHOD: Fifty-six patients were undergone adenoidectomy. Intra-operatively, soft palate was retracted with catheter, adenoid was indirectly visualized using laryngoscope and removed with adenoid curette. RESULT: All patients were free of snore postoperatively, conductive hearing loss was improved as well. In addition, hearing threshold was stable in two patients with inner ear malformation postoperatively. The blood loss was 20-50 ml, the surgical time was 5-20 min. No patient complained of blood bleed and other complications postoperatively. CONCLUSION: Adenoidectomy under indirect laryngoscope visualization is easy-performed, cost-effective surgical procedures. As well, it is safe and satisfied with surgeons and patients.

Adenoidectomy↗
PubMed2006

[The factors associated with viral relapse after interferon treatment in chronic hepatitis C patients].

OBJECTIVE: To investigate the relationship between hepatitis C virus (HCV) genotype, serum viral load and ALT levels, and the factors associated with the viral relapse after IFN treatment in patients with chronic hepatitis C. METHODS: The HCV RNA levels were determined with Cobas Amplicor Monitor Test, version 2.0, and HCV genotypes were examined by means of PCR products of 5' NTR digested with restriction endonucleases. The patients with chronic hepatitis C were treated with PEG-IFN alpha -2a and Roferon-A for 24 weeks. Those with a viral response after 24 week treatment were followed for an additional 24 weeks. The association of clinical characteristics, such as sex, age, the way of the HCV infection, IFN treatment history and platelet counts, and the HCV genotype, virus load and medicine used for the viral relapse after IFN treatment were analyzed. RESULTS: Of the 208 chronic hepatitis C patients, the ALT levels were not related to HCV RNA levels (r = 0.093, P > 0.05). No difference of ALT levels between HCV genotypes was found, and the HCV RNA load was also of no difference between HCV genotype 1 patients and non 1 patients. Of the 119 patients with viral response after 24 week treatment, 58 cases (48.7%) relapsed after another 24 week's follow-up. Relapse was not significantly related to the clinical characteristics, such as sex, age, mode of the infection, treatment history of IFN, AST/ALT ratio, platelet counts and the baseline viral load. Among patients with genotype 1 virus, the relapse rate was significantly higher than those patients with non-genotype 1 virus (54.5% vs 32.1%, P=0.039). The relapse rate after PEG-IFN alpha -2a treatment was lower than that of Roferon-A treatment (47.0% vs. 52.8%), but not significantly. CONCLUSION: The viral relapse of chronic hepatitis C patients after IFN treatment was significantly associated with the genotypes of the HCV.

Antiviral Agents↗
PubMed2006

[SSR polymorphism on the waxy gene locus and their relationship to amylose content in wheat].

Variation of one simple sequence repeat (SSR)(AT (AT)n AT) in the 3 end of the waxy gene was analyzed in samples of 32 cultivars, including different wheat cultivars in Shandong region and representing a wide distribution range of amylose content (AC) in cultivated wheat. In this study, we found two fragments were present in all cultivars, one of 204bp, the expected size, and one of 225-346bp. 204bp fragment located on the chromosome 7DS, while 225-346bp fragment located on the chromosome 7AS. That is, Wx-Ala gene and Wx-Dla gene present in all wheat lines, but the larger fragment showed length polymorphism. The result showed that the amylose level is highly positive correlated with the length of the polymorphic SSR. Amplified fragment is long in high AC cultivars and electrophoresis migration rate is small, while the fragment is short in low AC cultivars and electrophoresis migration rate is large. AC is highly diverse among different lines with the various SSR genotypes. Although the SSR variation did not seem to have obvious function in the synthesis of the starch synthase encoded by the waxy gene, the correlation between the SSR and AC level could be used as molecular marker for quality improvement in wheat programs.

Amylose↗
PubMed2006

[Short-term effects of chemotherapy combined with hydroxycamptothecine and oxaliplatin in treatment of recurrent and metastatic colorectal cancer].

BACKGROUND & OBJECTIVE: Although 5-fluarouracil (5-FU)-based chemotherapy has become a standard regimen for treatment of recurrent and metastatic colorectal cancer, the efficacy, as a second line therapy, is not high. Thus, it is necessary to find a new regimen as a substitute. This study was to evaluate the short-term effects and toxicity of combination of hydroxycamptothecine (HCPT) plus oxaliplatin (L-OHP) protocol in the treatment of recurrent and metastatic colorectal cancer. METHODS: 47 patients with pathological evidence of recurrent and metastatic colorectal cancer were enrolled and treated with HCPT plus L-OHP regimen for 86 cycles. All patients were treated with (L-OHP 130 mg/m(2), day 1 and HCPT 6 mg/m(2), day 1-4) and the chemotherapy was repeated every 3 weeks. The short-term effects and side effects were evaluated after every 2 cycles for each patient. RESULTS: 38 cases were evaluable and RR [complete remission (CR)+partial remission (PR)] was 36.8% (14/38). KPS was improved in 20 cases (52.6%). In total 86 cycles, leucopenia occurred in 59 cycles (68.6%), 18 cycles (30.5%) in grade III and IV, and diarrhea occurred in 48 cycles (55.8%), 18 cycles (37.5%) in grade III and IV. One year survival rate was 40.0% and medium overall survival (mOS) and medium progression free survival (mPFS) were 11.7 and 7.8 months, respectively. CONCLUSIONS: HCPT plus L-OHP regimen achieved relatively satisfactory short-term effects in the treatment for colorectal cancer patients, who suffered from recurrence and metastasis after the first-line chemotherapy with 5-FU. The main toxicities of the regimen were leucopenia and diarrhea.

Adenocarcinoma↗
PubMed2005

Cardiac glycoside downregulates NHE3 activity and expression in LLC-PK1 cells.

Ouabain, a cardiotonic steroid and a specific inhibitor of the Na(+)-K(+)-ATPase, has been shown to significantly inhibit transcellular Na(+) transport without altering the intracellular Na(+) concentration ([Na(+)](i)) in the epithelial cells derived from the renal proximal tubules. We therefore studied whether ouabain affects the activity and expression of Na(+)/H(+) exchanger isoform 3 (NHE3) representing the major route of apical Na(+) reabsorption in LLC-PK(1) cells. Chronic basolateral, but not apical, exposure to low-concentration ouabain (50 and 100 nM) did not change [Na(+)](i) but significantly reduced NHE3 activity, NHE3 protein, and mRNA expression. Inhibition of c-Src or phosphoinositide 3-kinase (PI3K) with PP2 or wortmannin, respectively, abolished ouabain-induced downregulation of NHE3 activity and mRNA expression. In caveolin-1 knockdown LLC-PK(1) cells, ouabain failed to downregulate NHE3 mRNA expression and NHE3 promoter activity. Ouabain response elements were mapped to a region between -450 and -1,194 nt, where decreased binding of thyroid hormone receptor (TR) and Sp1 to their cognate cis-elements was documented in vitro and in vivo by protein/DNA array analysis, EMSA, supershift, and chromatin immunoprecipitation. These data suggest that, in LLC-PK(1) cells, ouabain-induced signaling through the Na(+)-K(+)-ATPase-Src pathway results in decreased Sp1 and TR DNA binding activity and consequently in decreased expression and activity of NHE3. These novel findings may represent the underlying mechanism of cardiotonic steroid-mediated renal compensatory response to volume expansion and/or hypertension.

Animals↗
PubMed2005

Poly[strontium(II)-mu2-aqua-mu5-4-carboxylatophenoxyacetato].

In the title three-dimensional coordination polymer, [Sr(4-CPOA)(H2O)](n) (where 4-CPOA2- is the 4-carboxylatophenoxyacetate dianion, C9H6O5), each Sr(II) atom displays a bicapped triangular prismatic configuration, defined by five carboxyl and one ether O atom from five different 4-CPOA2- ligands, as well as two water molecules. The Sr(II) atoms are covalently linked by 4-CPOA2- ligands and water molecules, giving rise to a three-dimensional open framework. In previously studied polymers of this type, the 4-CPOA2- ligand shows a variety of binding modes to metal ions, from mono- to pentadentate. In the present Sr(II) complex, a novel hexadentate bridging mode is observed.

Journal Article↗
PubMed2005

XBP1 forms a regulatory loop with BMP-4 and suppresses mesodermal and neural differentiation in Xenopus embryos.

The active form of the Xenopus X-box binding protein 1 (xXBP1) partially synergizes and partially antagonizes with BMP-4 signaling. xXBP1 overexpression inhibits mesoderm differentiation and formation of neural tissues. A functional knockdown promotes differentiation of lateral and dorsal mesoderm but not of ventral mesoderm and of neuroectoderm. We show that the active form of xXBP1 in gastrula and early neurula stage embryos is generated by removal of exon 4 and not by an endoribonuclease activity in the endoplasmic reticulum. The N-terminal region of xXBP1 which contains the basic leucine-zipper also contains a nuclear localization signal and both, the N-terminal as well as the C-terminal regions are required for xXBP1 function. The effects of xXBP1 are in part correlated to a regulatory loop between xXBP1 and BMP-4. xXBP1 and BMP-4 stimulate mutually the transcription of each other, but xXBP1 inhibits the BMP-4 target gene, Xvent-2. Both, in vitro and in vivo assays demonstrate that xXBP1 interacts with BMP-4 and Xvent-2B promoters. GST-pulldown assays reveal that xXBP1 can interact with c-Jun, the transcriptional co-activator p300 and with the BMP-4 responsive Smad1. On the other hand, xXBP1 also binds to the inhibitory Smads, Smad6 and Smad7, that can act as transcriptional co-repressors. Based on these data, we conclude that xXBP1 might function as an inhibitor of mesodermal and neural tissue formation by acting either as transcriptional activator or as repressor. This dual activity depends upon binding of co-factors being involved in the formation of distinct transcription complexes.

Alternative Splicing↗
PubMed2005

Fetal source extraction from magnetocardiographic recordings by dependent component analysis.

Fetal magnetocardiography (fMCG) has been extensively reported in the literature as a non-invasive, prenatal technique that can be used to monitor various functions of the fetal heart. However, fMCG signals often have low signal-to-noise ratio (SNR) and are contaminated by strong interference from the mother's magnetocardiogram signal. A promising, efficient tool for extracting signals, even under low SNR conditions, is blind source separation (BSS), or independent component analysis (ICA). Herein we propose an algorithm based on a variation of ICA, where the signal of interest is extracted using a time delay obtained from an autocorrelation analysis. We model the system using autoregression, and identify the signal component of interest from the poles of the autocorrelation function. We show that the method is effective in removing the maternal signal, and is computationally efficient. We also compare our results to more established ICA methods, such as FastICA.

Algorithms↗
PubMed2005

Cubane, cuneane, and their carboxylates: a calorimetric, crystallographic, calculational, and conceptual coinvestigation.

[reaction: see text] This study is a multinational, multidisciplinary contribution to the thermochemistry of dimethyl1,4-cubanedicarboxylate and the corresponding isomeric, cuneane derivative and provides both structural and thermochemical information regarding the rearrangement of dimethyl 1,4-cubanedicarboxylate to dimethyl 2,6-cuneanedicarboxylate. The enthalpies of formation in the condensed phase at T = 298.15 K of dimethyl 1,4-cubanedicarboxylate (dimethyl pentacyclo[4.2.0.0.(2,5)0.(3,8)0(4,7)]octane-1,4-dicarboxylate) and dimethyl 2,6-cuneanedicarboxylate (dimethyl pentacyclo[3.3.0.0.(2,4)0.(3,7)0(6,8)]octane-2,6-dicarboxylate) have been determined by combustion calorimetry, delta(f) H(o)m (cr)/kJ x mol(-1) = -232.62 +/- 5.84 and -413.02 +/- 5.16, respectively. The enthalpies of sublimation have been evaluated by combining vaporization enthalpies evaluated by correlation-gas chromatography and fusion enthalpies measured by differential scanning calorimetry and adjusted to T = 298.15 K, delta(cr) (g)Hm (298.15 K)/kJ x mol(-1) = 117.2 +/- 3.9 and 106.8 +/- 3.0, respectively. Combination of these two enthalpies resulted in delta(f) H(o)m (g., 298.15 K)/kJ x mol(-1) of -115.4 +/- 7.0 for dimethyl 1,4-cubanedicarboxylate and -306.2 +/- 6.0 for dimethyl 2,6-cuneanedicarboxylate. These measurements, accompanied by quantum chemical calculations, resulted in values of delta(f) Hm (g, 298.15 K) = 613.0 +/- 9.5 kJ x mol(-1) for cubane and 436.4 +/- 8.8 kJ x mol(-1) for cuneane. From these enthalpies of formation, strain enthalpies of 681.0 +/- 9.8 and 504.4 +/- 9.1 kJ x mol(-1) were calculated for cubane and cuneane by means of isodesmic reactions, respectively. Crystals of dimethyl 2,6-cuneanedicarboxylate are disordered; the substitution pattern and structure have been confirmed by determination of the X-ray crystal structure of the corresponding diacid.

Journal Article↗
PubMed2005

The thermochemistry of 2,4-pentanedione revisited: observance of a nonzero enthalpy of mixing between tautomers and its effects on enthalpies of formation.

The enthalpies of formation of pure liquid and gas-phase (Z)-4-hydroxy-3-penten-2-one and 2,4-pentanedione are examined in the light of some more recent NMR studies on the enthalpy differences between gas-phase enthalpies of the two tautomers. Correlation gas chromatography experiments are used to evaluate the vaporization enthalpies of the pure tautomers. Values of (51.2 +/- 2.2) and (50.8 +/- 0.6) kJ.mol(-1) are measured for pure 2,4-pentanedione and (Z)-4-hydroxy-3-penten-2-one, respectively. The value of (50.8 +/- 0.6) kJ.mol(-1) can be contrasted to a value of (43.2 +/- 0.2) kJ.mol(-1) calculated for pure (Z)-4-hydroxy-3-penten-2-one when the vaporization enthalpy is measured in a mixture of tautomers. The difference is attributed to an endothermic enthalpy of mixing that destabilizes the mixture relative to the pure components. Calculation of new enthalpies of formation for (Z)-4-hydroxy-3-penten-2-one and 2,4-pentanedione in both the gas, Delta(f)H degrees (m)(g) = (-378.2 +/- 1.2) and (-358.9 +/- 2.5) kJ.mol(-1), respectively, and liquid phases, Delta(f)H degrees (m)(l) = (-429.0 +/- 1.0) and (-410.1 +/- 1.2) kJ.mol(-1), respectively, results in enthalpy differences between the two tautomers both in the liquid and gas phases that are identical within experimental error, and in excellent agreement with recent gas-phase NMR studies.

Journal Article↗
PubMed2005

Poly[[diaquabarium(II)]-mu5-m-phenylenedioxydiacetato]: a three-dimensional barium(II) coordination polymer.

In the title coordination polymer, [Ba(1,3-BDOA)(H2O)2]n (where 1,3-BDOA2- is the m-phenylenedioxydiacetate dianion, C10H8O6), each Ba(II) ion is ten-coordinated by six carboxyl O atoms and two ether O atoms from different 1,3-BDOA(2-) ligands, as well as by two water molecules, thus defining a dodecahedron. The Ba(II) atoms are covalently linked by 1,3-BDOA2- ligands in different crystallographic directions, giving rise to a three-dimensional open framework. The crystal structure is further stabilized by hydrogen bonds and pi-pi stacking interactions. In previously studied polymers of this type, the 1,3-BDOA2- ligand showed multiple bridging modes with metal ions, including bi-, tri-, tetra- and hexadentate. The title Ba(II) complex represents a novel three-dimensional coordination polymer constructed by octadentate bridging 1,3-BDOA2- ligands.

Journal Article↗
PubMed2005

[Craniofacial hyperhidrosis treated by video-assisted thoracoscopic sympathectomy].

OBJECTIVE: To investigate the feasibility, safety and prospect application value of video-assisted thoracoscopic sympathectomy utilized in the treatment of craniofacial hyperhidrosis. METHODS: Eighteen patients with craniofacial hyperhidrosis underwent sympathectomy from January 2003 to December 2004, including 10 cases combined with palmar hyperhidrosis. There were 17 males and 1 females with a mean age of 36.5 years (ranges, 25-42). Sympathetic chain was transected just below the stellate ganglion in pure craniofacial hyperhidrosis. Additional T(3) sympathectomy was performed in those patients combined with palmar hyperhidrosis. RESULTS: There were no surgical complication or surgical mortality cases. Seventeen patients achieved improvement of craniofacial hyperhidrosis without recurrent symptoms, but one had partial remission due to thoracic adhesion and false location of the ganglions. The effective rate was 97% (35/36). No recurrent symptoms occurred after a mean of 8.3 months of follow-up. No relapse occurred. Fifteen patients (83%) developed compensatory sweating of the trunk and lower limbs. Six patients (33%) presented palmar dry (severe hypohidrosis) and they all can tolerate the condition. All patients were satisfied with the outcomes of their operations. CONCLUSION: The initial results show that thoracoscopic sympathectomy is a safe and effective method for the treatment of craniofacial hyperhidrosis.

Adult↗
PubMed2005

Ultrafast breathinglike oscillation in the exciton density of ZnSe quantum wells.

The spatial density profile of a low-density exciton ensemble in ZnSe quantum wells shows a breathinglike oscillation on a 30-ps time scale. This breathing results from the emission of the first acoustic phonon at the end of the quasiballistic transport phase of the excitons which reverses their direction of propagation. Since the scattering destroys the phase of the excitonic wave function, one can deduce simultaneously the coherence length and the coherence time of excitonic transport by evaluation of the oscillation measured from a single experiment. The breathing, which can be modeled by Monte Carlo simulations, is quenched for rising lattice temperature, i.e., increasing phonon absorption, and in samples with significant disorder. These results were obtained by time-resolved nanophotoluminescence with 5 ps and 250 nm temporal and spatial resolution, respectively.

Journal Article↗
PubMed2005

[The value of mediastinoscopy in the diagnosis of thoracic sarcoidosis].

OBJECTIVE: To evaluate the role of mediastinoscopy in the diagnosis of thoracic sarcoidosis. METHODS: This study was retrospective. Mediastinoscopy was performed in a total of 30 patients who had enlarged mediastinal lymph nodes on chest CT and were clinically suspected of having sarcoidosis from November 1999 to June 2004. Biopsy tissues from peritracheal, retrosternal, subcarinal, or bilateral hilar regions were obtained for pathological study. RESULTS: All the patients had a definitive pathologic diagnosis, consisting of 24 cases of stage I and 6 stage II thoracic sarcoidosis. The diagnostic consistency between preoperation and postoperation was 40% (12/30), and the misdiagnosis rate preoperation was 60% (18/30). In this series, the initial diagnosis had been malignancy in 17 cases (57%), of whom 3 had received chemotherapy at local hospitals. The overall incidences of postoperative complication and mortality were 0. CONCLUSION: Our experience showed that mediastinoscopy is a valuable procedure which helps confirm the diagnosis of mediastinal disease. Given its safety and efficacy, it should be considered in the diagnosis and differential diagnosis of thoracic sarcoidosis of stage I or II.

Adult↗
PubMed2005

Monitoring age-related susceptibility of young mice to oral Salmonella enterica serovar Typhimurium infection using an in vivo murine model.

Neonates and young children are acutely susceptible to infections by gastrointestinal bacterial pathogens, such as Salmonella enterica serovar Typhimurium (S. typhimurium). To reveal age-related differences in susceptibility to this pathogen, we used in vivo bioluminescence imaging (BLI) to monitor the progression of infection in neonatal (1-wk-old), suckling (2-wk-old), juvenile (4-wk-old), and adult (6-wk-old) BALB/c mice. Mice were orally infected with various doses of a bioluminescent-labeled wild-type or mutant S. typhimurium strain, and progression of infection was monitored by BLI for 2 wks. We found that neonatal and suckling mice were more susceptible to the wild-type strain at inoculum sizes 4 and 2 log(10)'s lower for neonatal and suckling mice, respectively, than those for adult mice. At the lower inocula, newborn mice showed disseminated systemic infection as indicated by the pattern of photon emission assessed by BLI, whereas no bioluminescent signals were detectable in adult mice. In addition, an orgA(-) mutant strain of S. typhimurium with reduced virulence in adult mice produced systemic infection in newborn, suckling, and juvenile mice. Furthermore, as low as 3 log(10) CFU could be detected by BLI in tissue. The present study demonstrates that susceptibility to S. typhimurium infection decreases with age. Also, we established that BLI can be used to monitor the progression of infection in mice. Thus, this model of age-related susceptibility to S. typhimurium using BLI can be used to advance our understanding of the mechanisms involved in newborn susceptibility to infection.

Age Factors↗
PubMed2005

AML1-ETO fusion protein up-regulates TRKA mRNA expression in human CD34+ cells, allowing nerve growth factor-induced expansion.

The AML1-ETO fusion protein, generated by the t(8;21) in acute myeloid leukemia (AML), exerts dominant-negative functions and a variety of gains of function, including a positive effect on the growth of primary human CD34+ hematopoietic stem/progenitor cells. We now show that AML1-ETO expression up-regulates the level of TRKA mRNA and protein in these cells and that AML1-ETO-expressing CD34+ hematopoietic cells grown in the presence of five early-acting hematopoietic cytokines further proliferate in response to nerve growth factor (NGF). These cells also show a unique response to NGF and IL-3; namely, they expand in liquid culture. To determine the biological relevance of our findings, we analyzed 262 primary AML patient samples using real-time RT-PCR and found that t(8;21)-positive AML samples express significantly higher levels of TRKA mRNA than other subtypes of AML. NGF, which is normally expressed by bone marrow stromal cells, could provide important proliferative or survival signals to AML1-ETO-expressing leukemic or preleukemic cells, and the NGF/TRKA signaling pathway may be a suitable target for therapeutic approaches to AML.

Antigens, CD34↗
PubMed2005

Electrical coupling and release of K+ from endothelial cells co-mediate ACh-induced smooth muscle hyperpolarization in guinea-pig inner ear artery.

The physiological basis of ACh-elicited hyperpolarization in guinea-pig in vitro cochlear spiral modiolar artery (SMA) was investigated by intracellular recording combined with dye labelling of recorded cells and immunocytochemistry. We found the following. (1) The ACh-hyperpolarization was prominent only in cells that had a low resting potential (less negative than -60 mV). ACh-hyperpolarization was reversibly blocked by 4-DAMP, charybdotoxin or BAPTA-AM, but not by N(omega)-nitro-L-arginine methyl ester, glipizide, indomethacin or 17-octadecynoic acid. (2) Ba(2)(+) (100 microm) and ouabain (1 microm) each attenuated ACh-hyperpolarization by approximately 30% in smooth muscle cells (SMCs) but had only slight or no inhibition in endothelial cells (ECs). A combination of Ba(2)(+) and 18beta-glycyrrhetinic acid near completely blocked the ACh-hyperpolarization in SMCs. (3) High K(+) (10 mm) induced a smaller hyperpolarization in ECs than in SMCs, with an amplitude ratio of 0.49 : 1. Ba(2)(+) blocked the K(+)-induced hyperpolarization by approximately 85% in both cell types, whereas ouabain inhibited K(+)-hyperpolarization differently in SMCs (19%) and ECs (35%) and increased input resistance. 18beta-Glycyrrhetinic acid blocked the high K(+)-hyperpolarization in ECs only. (4) Weak myoendothelial dye coupling was detected by confocal microscopy in cells recorded with a propidium iodide-containing electrode for longer than 30 min. A sparse plexus of choline acetyltransferase-immunoreactive (ChAT) fibres was observed around the SMA and its up-stream arteries. (5) Evoked excitatory junction potentials (EJP) were partially blocked by 4-DAMP in half of the cells tested. We conclude that ACh-induced hyperpolarization originates from ECs via activation of Ca(2)(+)-activated potassium channels, and is independent of the release of NO, cyclo-oxygenase or cytochrome P450 products. ACh-induced hyperpolarization in smooth muscle cells involves two mechanisms: (a) electrical spread of the hyperpolarization from the endothelium, and (b) activation of inward rectifier K(+) channels (K(ir)) and Na(+)-K(+) pump current by elevated interstitial K(+) released from the endothelial cells, these being responsible for about 60% and 40% of the hyperpolarization, respectively. The role ratio of K(ir) and pump current activation is at 8 : 1 or less.

Acetylcholine↗