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Hao Li

Publications and source records attributed to Hao Li.

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

[Research of modified rat laryngeal transplantation model].

OBJECTIVE: To study modified rat laryngeal transplantation model. METHODS: Eighty isogeneic histocompatible F344 rats were randomized into control and experimental groups. Strome model of laryngeal transplantation was established in the the control group, and in the experimental group, the ascending pharyngeal artery was preserved and the base of the tongue, larynx and pharyngolarynx were harvested as a complex allograft followed by end-to-end anastomosis of the both allograft common carotid arteries with the recipient common carotid artery and the anterior jugular vein, respectively. The arterial and nenous patency rate and allograft viability rate were compared between the two groups. RESULTS: The artery and vein patency rates and graft survival rate were 30%, 15%, and 30% in the control group, and 75%, 65%, and 80% in the experimental group, respectively, showing significant difference between the two groups (P<0.05). CONCLUSION: In modified rat laryngeal transplantation model, the allograft viability rate and vessel patency rate are improved, which provides a good model for immunological study of larynx transplantation.

Anastomosis, Surgical↗
PubMed2006

[An experimental research on the combination treatment of sFLK-1 gene therapy combined with gamma knife].

OBJECTIVE: To evaluate whether the sustained expression by adenovirus-mediated gene (sFLK-1) transfer can enhance the treatment efficacy of gamma knife radiosurgery. METHODS: The mouse sFLK-1 gene was cloned to construct the recombinant adenovirus. The gliomata growing in BALB/c female nude mice with an initial mean volume of (109.3 +/- 20.5) mm3 were treated with gamma knife alone (13 Gy on day 12), sFLK-1 adenovirus alone (1 x 10(9) plaque-forming units, PFU was given to two mouse tail vein by injections, 7 and 14 days), gamma knife associated with sFLK-1 adenovirus or control adenovirus (1 x 10(9) PFU was given to two mouse tail vein by injections, 13 and 17 days). After the completion of therapy, the tumor size was recorded. The microvessel density (MVD) and tumor apoptosis were evaluated by immunohistochemical means. RESULTS: As comparing with three other control groups, the combination treatment group with sFLK-1 gene therapy and gamma knife not only significantly reduced tumor volume and prolonged the life span of tumor burden mice as well. In addition, the average tumor weights were lower in sFLK-1 combined with gamma knife group than in any other control group. Immunohistochemical analysis of glioma demonstrated a decreased MVD and a high apoptosis cell rate in sFLK-1 combined with gamma knif group. CONCLUSION: The antitumor effect of gamma knife can be potentiated by sFLK-1 gene therapy. Thus the combination of sFLK-1 gene therapy and gamma knife results an additive effect of antitumor. The observation may provide an important strategy for treatment cancer metastasis.

Adenoviridae↗
PubMed2006

[Correlation of cervical lymphatic metastasis to prognosis of T3-T4 glottic cancer].

BACKGROUND & OBJECTIVE: The cervical lymphatic metastasis rate of glottic cancer is low, and has seldom been reported. This study was to explore the factors related to cervical lymphatic metastasis of T3-T4 glottic cancer, and analyze its correlation to prognosis. METHODS: Clinical data of 83 patients with T3-T4 glottic cancer, treated in Cancer Center of Sun Yat-sen University from 1992 to 2000, were reviewed retrospectively. The lymphatic metastasis rate, distribution of metastatic lymph nodes, influence factors of neck recurrence of cN0 glottic cancer, and correlation of cervical lymphatic metastasis to prognosis of T3-T4 glottic cancer were analyzed. RESULTS: Overall lymphatic metastasis rate was 20.5%. The neck recurrence rate of cN0 patients was 14.3%. Most metastatic lymph nodes located at the ipsilateral levels II, III, and IV, while only 1 located at the contralateral level II. For cN0 patients, there was no difference in the neck recurrence rate between observation group and prophylactic cervical radiation group (P=0.772). Histopathologic differentiation affected the neck recurrence of cN0 patients (P=0.028); while T stage did not relate to the neck recurrence (P=0.217). The prognosis of cN+ patients was poorer than that of cN0 patients (P<0.001). The neck recurrence of CN0 patients did not affect the prognosis (P=0.460). CONCLUSION: Most metastatic lymph nodes of T3-T4 glottic cancer locate at the ipsilateral levels II, III, and IV. Poor differentiation is significantly correlated to high risk of neck recurrence among cN0 patients. However, the recurrence does not affect the prognosis. Close observation should be done to the cervix of cN0 patients; while neck dissection should be done to cN+ patients.

Adult↗
PubMed2006

[In vitro chemo-sensitivity MTT assay guided intraperitoneal chemotherapy for malignant ascites].

OBJECTIVE: To evaluate the feasibility and efficacy of intraperitoneal chemotherapy for malignant ascites caused by different types of abdominal cancers guided by chemo-sensitivity methyl tetrojolium coloremetric (MTT) assay in vitro. METHODS: Cancer cells in the malignant ascites were collected for MTT assay to determine the chemo-sensitivity. The drug producing the highest or the second highest inhibition rate was selected for intraperitoneal chemotherapy. The correlation between the results of MTT assay and the response of malignant ascites, the clinical features, Karnofsky performance score (KPS) and prognosis were analyzed. RESULTS: MTT assay indicated that Taxotere (TXT) and Hydroxycamptothecin (HCPT) were the most effective to cancer cells in malignant ascites, and HCPT was mostly frequently used for intraperitoneal chemotherapy (56.9%). Twenty-four patients showed response by intraperitoneal chemotherapy (complete response: 7; partial response: 17) with a slightly significant correlation between the results of MTT assay and response of malignant ascites (P = 0. 014). The KPS of the responders was improved significantly (P < 0.001), and the response of malignant ascites to intraperitoneal chemotherapy was demostrated as an independent prognostic factor by multi-variate analysis in this series. CONCLUSION: In vitro chemo-sensitivity MTT assay guided intraperitoneal chemotherapy for malignant ascites is simple, effective and safe, which can improve the KPS and prognosis of the responders.

Adenocarcinoma↗
PubMed2005

Synthesis and characterization of 3,5-bis(2-hydroxyphenyl)-1,2,4-triazole functionalized tetraaryloxy perylene bisimide and metal-directed self-assembly.

[structure: see text] New perylene bisimide dyes bearing 3,5-bis(2-hydroxyphenyl)-1,2,4-triazole receptor units with different spacers have been synthesized and characterized. The fluorescence and electronic properties of these compounds have been studied. MALDI-TOF, UV-vis, and fluorescence titration experiments proved that monotopic perylene bisimide ligands could be assembled into dimmers by Fe(III) coordination. The coordination properties of the ditopic perylene bisimide ligands have also been studied preliminarily. Furthermore, the SEM images indicated that well-defined nanoscale structures could be fabricated by self-assembly due to metal ion coordination and pi-pi stacking interactions of perylene rings with the help of a proper spacer.

Journal Article↗
PubMed2005

Sensitive and selective liquid chromatography-electrospray ionisation-mass spectrometry analysis of astragaloside-IV in rat plasma.

Astragaloside-IV (3-O-beta-d-xylopyranosyl-6-O-beta-d-glucopyranosyl-cycloastragenol) is the major active constituent contained in Radix Astragali. This paper describes a rapid, sensitive and specific assay for quantitative determination of astragaloside-IV in rat plasma. After a liquid/liquid extraction (LLE) with n-butanol and high-performance liquid chromatography (HPLC) gradient separation with acetonitrile-NH4Cl solution (0.5 micromol/L) as the mobile phase, the anions adduct [M + Cl]- at m/z 819.4 of astragaloside-IV, and [M + Cl]- at m/z 815.35 of internal standard (IS) digoxin were analyzed by electrospray ionisation-mass spectrometry (LC-ESI-MS) in selected ion monitoring (SIM) mode. Chromatographic separation was achieved in less than 9 min and calibration curve was linear over a concentration range of 2-200 ng/ml. The described assay method was successfully applied to the preclinical pharmacokinetic study of astragaloside-IV. After intragastric administration of astragaloside-IV to rats, Cmax and Tmax of astragaloside-IV were 134.73 +/- 39.86 ng/ml and 1.5 h, respectively, and the elimination half-life (t1/2) was 5.45 +/- 0.39 h.

Animals↗
PubMed2005

Simple, sensitive and rapid LC-ESI-MS method for the quantitation of lafutidine in human plasma--application to pharmacokinetic studies.

A sensitive and specific liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS) method has been developed and validated for the identification and quantification of lafutidine in human plasma. Lafutidine and internal standard were isolated from plasma samples by liquid-liquid extraction with diethyl ether. The chromatographic separation was accomplished on a stainless-steel column (C18 Shim-pack 5 microm 150 mm x 2.0 mm i.d. Shimadzu) at a flow rate of 0.2 ml/min by a gradient elution. Detection was performed on a single quadrupole mass spectrometer by selected ion monitoring (SIM) mode via electrospray ionization (ESI) source. The method was proved to be sensitive and specific by testing six different plasma batches. Linearity was established for the range of concentrations 1.0-400.0 ng/ml with a coefficient of determination (r) of 0.9998 and good back-calculated accuracy and precision. The intra- and inter-day precision (R.S.D.%) was lower than 10% and accuracy ranged from 85 to 115%. The lower limit of quantification was identifiable and reproducible at 0.5 ng/ml with 0.2 ml plasma. The proposed method enables the unambiguous identification and quantification of lafutidine for pharmacokinetic, bioavailability or bioequivalence studies.

Acetamides↗
PubMed2005

Genome-wide identification of the regulatory targets of a transcription factor using biochemical characterization and computational genomic analysis.

BACKGROUND: A major challenge in computational genomics is the development of methodologies that allow accurate genome-wide prediction of the regulatory targets of a transcription factor. We present a method for target identification that combines experimental characterization of binding requirements with computational genomic analysis. RESULTS: Our method identified potential target genes of the transcription factor Ndt80, a key transcriptional regulator involved in yeast sporulation, using the combined information of binding affinity, positional distribution, and conservation of the binding sites across multiple species. We have also developed a mathematical approach to compute the false positive rate and the total number of targets in the genome based on the multiple selection criteria. CONCLUSION: We have shown that combining biochemical characterization and computational genomic analysis leads to accurate identification of the genome-wide targets of a transcription factor. The method can be extended to other transcription factors and can complement other genomic approaches to transcriptional regulation.

Amino Acid Motifs↗
PubMed2005

Significance and relationship between infiltrating inflammatory cell and tumor angiogenesis in hepatocellular carcinoma tissues.

AIM: To investigate the relationship between infiltrating inflammatory cell and tumor angiogenesis in hepatocellular carcinoma (HCC) tissues and their clinicopathological features. METHODS: The paraffin-embedded specimens from 70 cases with HCC were stained using EliVision immunohistochemistry with mAbs against CD68, tryptase, and CD34. The counts of tumor-associated macrophage (TAM), mast cell (MC) and tumor microvessel (MV) were performed in the tissue sections. RESULTS: The mean counts of TAM, MC, and MV in HCC tissues were significantly higher than those in pericarcinomatous liver tissues (TAM: 69.31+/-11.58 vs 40.23+/-10.36; MC:16.74+/-5.67 vs 7.59+/-4.18; MV: 70.11+/-12.45 vs 38.52+/-11.16, P<0.01). The MV count in the patients with metastasis was markedly higher than that with non-metastasis (P<0.01). In addition, the MC count in the patients with poorly differentiated HCC was obviously higher than that with well differentiated HCC (P<0.01). The correlation analysis showed that the TAM count was significantly correlated with the count of MV (r=0.712, P<0.01), and the MC count was obviously correlated with the MV count (r=0.336, P<0.05). CONCLUSION: TAM and MC might be closely related to the enhancement of tumor angiogenesis. The MV count might be associated with tumor invasion and metastasis. Moreover, the MC count might be associated with tumor differentiation and prognosis of HCC.

Adult↗
PubMed2005

Energy transfer switching in a bistable molecular machine.

[reaction: see text] A novel [2]rotaxane, containing pyrene and perylene bisimide as both stoppers and photoactive units, has been prepared. The shuttling of the protonated macrocycle switched the energy transfer (EN) from a pyrene moiety to a perylene moiety, which resulted in changes of fluorescence of the perylene moiety.

Journal Article↗
PubMed2005

Determination of schizandrin in rat plasma by high-performance liquid chromatography-mass spectrometry and its application in rat pharmacokinetic studies.

A sensitive liquid chromatography-mass spectrometric (LC/MS) method for the quantification of schizandrin in rat plasma was developed and validated after solid-phase extraction (SPE). Chromatographic separation was achieved on a reversed-phase Shimadzu C(18) column with the mobile phase of acetonitrile-sodium acetate (10 micromol/L) and step gradient elution resulted in a total run time of about 11.7 min. The analytes were detected using an electrospray positive ionization mass spectrometry in the selected ion monitoring (SIM) mode. A good linear relationship was obtained in the concentration range studied (0.005-2.000 microg/mL) (r=0.9999). Lower limit of quantification (LLOQ) was 5 ng/mL and the lower limit of detection (LLOD) was 2 ng/mL using 100 microL plasma sample. Average recoveries ranged from 75.85 to 88.51% in plasma at the concentrations of 0.005, 0.100 and 1.000 microg/mL. Intra- and inter-day relative standard deviations were 5.95-12.93% and 3.87-14.53%, respectively. This method was successfully applied for the pharmacokinetic studies in rats.

Animals↗
PubMed2005

Polymorphism of CYPIA1 and GSTM1 genes associated with susceptibility of gastric cancer in Shandong Province of China.

AIM: To explore whether polymorphisms of the CYPIA1 and GSTM1 genes are associated with susceptibility of stomach cancer. METHODS: A total of 102 stomach cancer cases and 62 healthy persons were diagnosed by pathology in 1998-2000 in the Qilu Hospital of Shandong University. Gene polymorphisms were detected by the PCR using sequence-specific primers. Data analysis of the case-control study was carried out using the unconditional logistic method. RESULTS: After adjustment for age, sex, educational levels, and occupation, the risk factors for stomach cancer were shown to be smoking, Helicobacter pylori (H pylori), and presence of the CYPIM G/G and GSTM1 O/O genotypes. Interaction was observed between the combined genotypes of either CYPIA1 G/G and GSTM1 O/O or H pylori infection, or GSTM1 O/O and H pylori infection or smoking. CONCLUSION: Polymorphisms of the CYPIA1 and GSTM1 genes, H pylori infection and smoking are related to susceptibility to stomach cancer.

Adult↗
PubMed2005

Chiral binaphthyl-derived amine-thiourea organocatalyst-promoted asymmetric Morita-Baylis-Hillman reaction.

[reaction: see text] A new bifunctional binaphthyl-derived amine thiourea organocatalyst has been developed to promote enantioselective Morita-Baylis-Hillman reaction of cyclohexenone with a wide range of aldehydes. The process, catalyzed by the amine thiourea, affords synthetically valuable chiral allylic alcohol building blocks in high yields and high enantioselectivities.

Aldehydes↗
PubMed2005

Simultaneous determination of loratadine and pseudoephedrine sulfate in human plasma by liquid chromatography-electrospray mass spectrometry for pharmacokinetic studies.

To support the pharmacokinetic and bioavailability study of an extended-release loratadine (LOR)/pseudoephedrine sulfate (PES) tablet, a high performance liquid chromatographic-electrospray ionisation-mass spectrometric method (LC-MS) was developed for the simultaneous determination of LOR and PES in human plasma. Diazepam (DP) and phenylpropanolamine (PPA) were used as internal standards for LOR and PES, respectively. Analytes were extracted from alkalized human plasma by liquid/liquid extraction using ethyl ether. Chromatographic separation was performed on an ODS column at flow rate of 0.2 ml/min. The total chromatographic run time was 10.5 min with the retention time of 7.1 min and 6.2 min for LOR and DP, respectively, and 2.2 min for both of PES and PPA. The LOQ was 10 pg/ml and 50 pg/ml for LOR and PES, respectively. The method is accurate and precise enough for its intended purpose.

Calibration↗
PubMed2005

Direct, facile aldehyde and ketone alpha-selenenylation reactions promoted by L-prolinamide and pyrrolidine sulfonamide organocatalysts.

[reaction: see text] A new catalytic method for direct alpha-selenenylation reactions of aldehydes and ketones has been developed. The results of exploratory studies have demonstrated that L-prolinamide is an effective catalyst for alpha-selenenylation reactions of aldehydes, whereas pyrrolidine trifluoromethanesulfonamide efficiently promotes reactions of ketones. Under optimized reaction conditions, using N-(phenylseleno)phthalimide as the selenenylation reagent in CH2Cl2 in the presence of L-prolinamide (2 mol %) or pyrrolidine trifluoromethanesulfonamide (10 mol %), a variety of aldehydes and ketones undergo this process to generate alpha-selenenylation products in high yields. Mechanistic insight into the L-proline and L-prolinamide catalyzed alpha-selenenylation reactions of aldehydes with N-(phenylseleno)phthalimide has come from theoretical studies employing ab initio methods and density functional theory. The results reveal that (1) the rate-limiting step of the process involves attack of the enamine intermediate at selenium in N-(phenylseleno)phthalimide and (2) the energy of the transition state for the reaction catalyzed by prolinamide is lower than that promoted by proline. This result is consistent with experimental observations. The role of hydrogen bond interactions in stabilizing the transition states for this process is also discussed.

Aldehydes↗
PubMed2005

Iliac hyperdense line: a new radiographic sign of gluteal muscle contracture.

BACKGROUND: A hyperdense line on the ilium that runs roughly parallel to the sacroiliac joint (we called it "iliac hyperdense line sign") was frequently observed on pelvic radiographs of patients with gluteal muscle contracture (GMC). A literature search revealed no description of this sign. OBJECTIVE: To determine the relationship between the iliac hyperdense line sign and GMC and to explore how this sign is formed. MATERIALS AND METHODS: Pelvic plain films of 103 cases of GMC and those of 200 control individuals were reviewed for the presence or absence of the iliac hyperdense line sign. Pelvic CT scans in 8 of 103 cases and 13 of 200 controls were analyzed with relation to the plain films. RESULTS: The iliac hyperdense line sign was visualized in 85 of 103 (82.5%) cases of GMC and none of the 200 controls. In the GMC group, pelvic CT scans showed a deformity of the posterior ilium. The lateral cortex of the posterior ilium took on a partly or completely anteroposterior course, while in the control group the course appeared as an oblique orientation from posteromedial to anterolateral. CONCLUSION: The iliac hyperdense line on pelvic plain film can be used as a radiographic sign to suggest a diagnosis of GMC. This sign might be a result of the long and persistent pulling effect of the contracted gluteus maximus muscle, which deforms the lateral cortex of the posterior ilium from an oblique course to an anteroposterior course tangential to the X-ray beam.

Adolescent↗
PubMed2005

High performance liquid chromatographic-mass spectrometric determination of ginsenoside Rg3 and its metabolites in rat plasma using solid-phase extraction for pharmacokinetic studies.

To support pharmacokinetic studies of ginsenosides, a novel method to quantitatively analyze ginsenoside Rg3 (Rg3), its prosapogenin ginsenoside Rh2 (Rh2) and aglycone 20(S)-protopanaxadiol (ppd) in rat plasma was developed and validated. The method was based on gradient separation of ginsenosides present in rat plasma using high performance liquid chromatography (HPLC), followed by detection with electrospray ionization(ESI) mass spectrometry (MS) in negative ion mode with the mobile phase additive, ammonium chloride (500 microM). Differentiation of ginsenosides was achieved through simultaneous detection of the [M(+)Cl(-)] adduct of ginsenoside Rg3 and [M(+)Cl(-)] adducts of its deglycosylated metabolites Rh2 and ppd, and other ions after solid phase extraction (SPE). The /specific ions monitored were m/z 819.50 for Rg3, m/z 657.35 for Rh2, m/z 495.40 for ppd and m/z 799.55 for the internal standard (digitoxin). The mean recoveries for Rg3, Rh2 and ppd were 77.85, 82.65 and 98.33%, respectively using 0.1 ml plasma for extraction. The lower limits of quantification were 10.0, 2.0 and 8.0 ng/ml (equivalent to 0.1, 0.02 and 0.08 ng in each 10 microl injection onto the HPLC column) for Rg3, Rh2 and ppd, respectively. The method has been demonstrated to be highly sensitive and accurate for the determination of Rg3 and its metabolites in rat plasma.

Animals↗