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Hua Li

Publications and source records attributed to Hua Li.

At least 91 records · Page 5Linked to original sources
PubMed2005

[Soluble expression and characterization of the immunoreactive multiepitope antigen of Toxoplasma gondii in E.coli].

OBJECTIVE: To obtain soluble expression product of immunoreactive recombinant multiepitope antigen of Toxoplasma gondii from E.coli. METHODS: The gene encoding the multiple epitopes (MEG) of Toxoplasma gondii was amplified by PCR from the original plasmid containing MEG gene and cloned into the prokaryotic soluble expression vector pET32a. After identification by enzyme digestion and sequencing, the positive recombinant plasmid pET32a-MEG was transformed into BL21(DE3), which was induced with IPTG for expression of the target antigen. The relative molecular mass, solubility and antigenicity of the expression products were analyzed by SDS-PAGE and Western blotting. RESULTS: The recombinant expression plasmid pET32a-MEG was successfully constructed and the highly efficient expression of the antigen was achieved after IPTG induction of E.coli. Improvement of the induction condition increased the expression product which accounted for about 28% of the total bacterial protein. The target protein, with good solubility and a relative molecular mass of about 31 000, was purified by immobilized metal affinity chromatography (Ni-NTA resin) and could be well recognized by mouse and rabbit antisera derived by infection of the animals with Toxoplasma gondii B36 and RH, respectively. CONCLUSION: The recombinant multiepitope antigen has good antigenicity and potential value in diagnosis and vaccine development of toxoplasmosis.

Animals↗
PubMed2005

[A colloidal gold immunochromatographic assay for detecting p38 antigen of Schistosome japonicum].

OBJECTIVE: To establish a colloidal gold immunochromatographic assay (GICA) for detecting Schistosome japonicum (Sj). METHODS: Eight monoclonal antibodies (mAbs) against Sj p38 antigen (1A6, 3C4, 3D12, 6F10, 6G12, 9H6, 9G7 and A5H) prepared previously were purified by protein-G affinity chromatography. The affinity constant (K(aff)) was determined by indirect enzyme-linked immunosorbent assay. All the mAbs were labeled with horseradish peroxidase by sodium oxidation method and the mAb pairs with high affinity and stability were identified according to their optical density at 450 nm (OD450). Four mAbs (1A6, 6G12, 9H6 and 9G7) were chosen for colloidal gold labeling. GICA was then performed by further optimization of the labeling and the conditions were determined. The sera of mice at different infection stages were examined with GICA dipstick, with the sera collected before infection and those of Toxoplasma gondii-infected mice as negative controls. RESULTS: The purity of the 8 mAbs was higher than 95% with K(aff) ranging from 2.8x10(-10) to 1x10(-8) mol/L. 9G7 coating (2.5 mg/ml) as the capture antibody and detection with 1A6 (diluted at 1:4) as the labeling antibody was determined as the best reaction model. With this combination, the positivity rates of the detection were 40%, 50%, 60% and 80% for mouse sera collected at 3, 4, 5 and 6 weeks after Schistosome japonicum infection, respectively, without positive results for the negative control samples. CONCLUSION: GICA established in this study is characterized by simplicity, rapidity and good sensitivity, and the prepared rSjP38 dipstick can test the circulating antigen SjP38 in early stage of infection.

Animals↗
PubMed2005

[Analysis of prognostic factors in 159 cases of cervical adenocarcinoma].

OBJECTIVE: To assess prognostic factors in patients with cervical adenocarcinoma. METHODS: Totally 159 cases of primary cervical adenocarcinoma were diagnosed in Cancer Hospital, Peking Union Medical College between 1992 and 2002. Clinical and pathological data including patients'age, delivery, tumor size, stage, grade, histological subtype, Pap smear, serum CA125 and treatment were reviewed. Mean age at presentation was 51.4 years. And the mean follow-up time was 59.8 months. According to the International Federation of Gynecology and Obstetrics (FIGO), patients with stages I-IV accounted for 13.2%, 34.0%, 45.3% and 7.5%, respectively. Survival analysis was carried out using SPSS software version 11.0. RESULTS: The overall 5-year survival rate was 47.9%. It was 86.1%, 56.4%, 36.0% and 0 for stages I, II, III and IV respectively. And 29.6% cases experienced recurrence or distant metastasis. The 5-year survival rate for them was 17.3%. In univariate analysis, tumor size (P = 0.009), stage (P < 0.01) and elevated serum CA125 values (P = 0.039) were significant factors for survival. In the group of 27 cases who received surgery, the survival was significantly poorer for cases with pelvic lymph node metastases (P = 0.001) and deep stromal invasion (P = 0.009). Only stage and pelvic lymph node metastases remained significant predictors for survival when multivariate analysis was performed. CONCLUSIONS: This retrospective study suggests that FIGO stage and pelvic lymph node metastasis are independent factors in prediction of survival in cervical adenocarcinoma. Survival rate remains to be improved.

Adenocarcinoma↗
PubMed2005

[The anatomic basis and the clinical treatment of the elbow joint stiffness after electric injury].

OBJECTIVE: To explore the optimal method for the treatment of the elbow joint stiffness accompanied with neural injury after electrical injury. METHODS: Thirty adult cadaver elbows were fixed and dissected to observe the attachments of the ligaments and the muscles around the joint, and its relationship with the major nerves. Ten patients with electric burns with stiffness of the elbow joint were treated by means of loosening the anterior and posterior fascicles of radial and ulnar collateral ligaments, at the same time down shifting the insertion of flexor muscles, replacing the ulnar nerve anteriorly, in order to reconstruct flexor and extension functions of the elbow. The effect was evaluated with biomechanics criteria. RESULTS: Through anatomical study, it was revealed that contracture of the posterior fascicles of the radial and ulnar collateral ligaments and triceps brachii muscle would result in stiffness of the elbow joint, and contracture due to disuse of the two anterior fascicles of the radial and ulnar collateral ligaments and M.biceps brachii would produce flexion deformity of the elbow joint. Postoperatively, the functions of the elbow joints of all the 10 patients recovered satisfactorily. Follow-up from 1 to 3 years showed no change in the range of flexion and extension movements of the elbows, and on the contrary, mobility of the elbow joints was improved. CONCLUSION: Loosening of the anterior and posterior fascicles of the two collateral ligaments and replacement of insertions of biceps and triceps are pivotal in the treatment of stiffness of the elbow joint. Meanwhile lowering the origins of forearm flexor muscles on epicondylus and replacing anteriorly the ulnar nerve can further improve the flexion, function of the joint and relieve compression of the nerve.

Adult↗
PubMed2005

[Clinicopathologic study of 24 patients with vulvar intraepithelial neoplasia III].

OBJECTIVE: To review the diagnosis methods and treatment modalities of vulvar intraepithelial neoplasia III (VINIII) and to analyse its prognostic factors. METHODS: The data of 24 patients with VINIII from 1992 to 2002 were retrospectively reviewed and analysed. RESULTS: Among these 24 patients, 62.5% (15 patients) were aged less than 40 years and 37.5% (9 patients) over 40 years. Human papillomavirus (HPV) infection was found in 53.3% and 2/9 of these two groups. Treatment modality for all patients was surgical excision including extended local excision (33.3%) and simple vulvectomy (66.7%). 3 patients (12.5%) developed recurrence. Positive resection margin was correlated with recurrence, while age, HPV infection, multifocality and resection modality were not. CONCLUSION: During recent years, the incidence of VIN has been on the increase in younger woman patients which maybe due to the increase of HPV infection, and the data show that the recurrence rate is correlated with positive margin. Treatment should be individualized and either extended local excision or simple vulvectomy is appropriate. Periodical follow-up should be done.

Adult↗
PubMed2005

[Observe the dissection of the tunnels of augmentation rhinoplasty under endoscope].

OBJECTIVE: To observe and analyse the dissection of the tunnels in traditional blind operation of augmentation rhinoplasty. METHODS: 11 Cases of augmentation rhinoplasty were collected and be observed by an endoscope as soon as the tunnels were formed during the operations. RESULTS: (1) Some of the tunnels did not go through one layer. (2) The bilateral cartilage separated in the mid-line. (3) There were two blood vessels in the surface of alar cartilage. There were perforating blood vessels in the edge of pyriform aperture. (4) In some cases whose incision were in unilateral alar margin, the tunnel were asymmetric. CONCLUSION: In some cases of traditional blind operation of augmentation rhinoplasty, tunnels were not suitable, they were asymmetric; and there were desmo and septa in the tunnels. Those might be the causes of complications post-op of augmentation rhinoplasty.

Endoscopes↗
PubMed2005

[Protection of oxyphenamone against cardiac arrest-reperfusion injury of isolated rat hearts].

AIM: To ascertain the protective effect of oxyphenamone, a novel inodilator, against myocardial ischemia-reperfusion injury. METHODS: A model of global myocardial ischemia-reperfusion injury (I-R) was established by arresting the infusion to heart 40 min followed by reperfusion 30 min in the preparations of rat Langendorff' s hearts. The protective effects of oxyphenamone were evaluated by the cardiac function, the activity of creatine phosphokinase (CPK) in coronary efflux, the myocardial energy metabolism and antioxidation, the membrane fluidity, the activity of ATPase, the calcium content and ultrastructure of mitochondria. RESULTS: Administration of oxyphenamone to the infused heart before cardiac arrest and during reperfusion ameliorated the decreases of myocardial contractile force and coronary flow and the increase of the activity of CPK in coronary efflux induced by cardiac arrest-reperfusion (A-R). At the concentration of 1-10 micromol x L(-1) oxyphenamone dose-dependently antagonized the decrease of myocardial adenosine triphosphate (ATP) and creatine phosphate (PCr) induced by A-R, increased the activities of myocardial superoxide dismutase (SOD) and glutathione peroxidase (GSH-px), decreased mitochondrial malondialdehyde (MDA) content and increased membrane fluidity, glutathione (GSH) content and the activities of GSH-px and ATPase of mitochondria. The parameters mentioned above even maintained at normal level when high concentration of oxyphenamone (10 micromol x L(-1)) was applied. Oxyphenamone also antagonized the mitochondrial calcium overload and the ultrastructure damage of mitochondria induced by A-R obviously. Addition of oxyphenamone (1-100 micromol x L(-1)) to the system of Fe2+-cysteine or Fe2+-H2O2, which could produce oxygen free radicals, decreased MDA content and increased GSH and membrane fluidity of mitochondria significantly. CONCLUSION: With the results of examinations of the cardiac physiological function, myocardial energy metabolism and antioxidation and the calcium content and ultrastructure of mitochondria, it is indicated that oxyphenamone could protect the isolated rat heart against cardiac arrest-reperfusion injury markedly and the mechanism of its action may be related to the antioxidative effect of this agent.

Animals↗
PubMed2005

[Bidens maximowicziana's adsorption ability and remediation potential to lead in soils].

Bidens maximowicziana's adsorption ability and remediation potential to lead were studied. The results show: (1) The Bidens maximowicziana has a strong adsorption to lead, the concentration of lead in plants increased linearly with the increase of lead concentration in soil. Then maximum concentration was 1509.3 mg x kg(-1) in roots and 2164.7 mg x kg(-1) in shoots when lead concentration in soil was 2000 mg x L(-1); (2) The lead concentration distribution order in the Bidens maximorwicziana is: leaf>stem>root>seed, which indicate that Bidens maximowicziana has a strong ability to transfer lead; (3) Uptaking ability differes in different vegetal periods. Maximum lead uptaking rate occured in the period of blooming for 40-60 days, in which daily uptake capacity was 15.81 mg x (kg x d)(-1) in roots and 19.83 mg x (kg x d)(-1) in shoots respectively. It can be concluded that Bidens maximowicziana appeares to be a moderate Pb accumulator making it suitable for phytoremediation of Pb contaminated soil.

Bidens↗
PubMed2005

[Clinical study on canalith repositioning procedure for benign paroxysmal positional vertigo of semicircular canal].

OBJECTIVE: To determine the effectiveness of canalith repositioning procedure for the treatment of benign paroxysmal positional vertigo (BPPV). METHOD: Medical records from two hundred and thirty cases with benign paroxysmal positional vertigo treated between January 2002 to June 2004 were analyzed retrospectively. Patients were divided into two groups,treatment group (122 cases) and control group (108 cases). Treatment group received a single treatment of canalith repositioning procedure based on the hypothesis that the vertigo and nystagmus of BPPV were due to debris floating in the long arm of the semicircular canal. Treatment outcome was analyzed after two weeks classified as cure, improvement or no change. RESULT: After a single treatment of canalith repositioning procedure, the vertigo and nystagmus in 88 cases of treatment group immediately or gradually disappeared in 1-2 weeks, 18 cases improved, 16 cases got no effect. Complete remission of vertigo and nystagmus was found in 72.1%, the total improvement rate was 86.9%. The vertigo and nystagmus in 51 cases of control group immediately disappeared in 1-2 weeks, 23 cases improved, 34 cases got no effect. Complete remission of vertigo and nystagmus was found in 47.2%, the total improvement rate was 68.5%, and the difference between groups was very significant (P < 0.001, P < 0.01). CONCLUSION: The canalith repositioning procedure was effective for most patients with benign paroxysmal positional vertigo and can be recommended as the first-line treatment modality.

Adult↗
PubMed2004

On-line chemiluminescence determination protocatechuic aldehyde and protocatechuic acid in pharmaceutical preparations by capillary electrophoresis.

Capillary electrophoresis (CE) with on-line direct chemiluminescence (CL) detection was first used in detecting protocatechuic aldehyde (PAH) and protocatechuic acid (PA) in their pharmaceutical preparations. It was found that the weak CL produced from the reaction of luminol with ferricyanide in an alkaline solution was strongly increased by PAH and PA which was separated by CE. Parameters affecting separation process and CL detection have been examined in detail. Under the optimum conditions, the baseline separation of PAH and PA was obtained within 6 min. The relative standard deviation (R.S.D.) for the analysis of PAH and PA was less than 1.1% for the migration time and 1.6% for the peak height. The detection limits (S/N=3) of PAH and PA were 7.0 x 10(-8)M and 5.0 x10(-8)M, respectively. The proposed method has been satisfactorily applied to the determination of PAH and PA in Salivia miltorrhrza pharmaceutical preparations.

Anticarcinogenic Agents↗
PubMed2004

New synthetic peptides can enhance gene expression of key antioxidant defense enzymes in vitro and in vivo.

Neurodegenerative, cardiovascular, and age-related disorders have been attributed to the cellular damage caused by elevated production of reactive oxygen species (ROS) and free radicals (FRs). These cannot be adequately defended by existing levels of key antioxidant enzymes. Two peptides, 8 and 14 amino acids long, were synthesized and found to up-regulate, at nanomolar concentrations, superoxide dismutase (SOD) and catalase (CAT) m-RNAs (9- to 12-fold) within 3 h, and then elevate by 5- to 10-fold the protein levels of SOD, CAT, and glutathione peroxidase (GPX) in rat primary cortical cultures. Kinetic studies showed that the peptide up-regulation of all three enzymes appears to be a coordinated process which occurs in vitro and in vivo. We also found that ischemia alone, without added drugs, can lead to enhanced gene expression of SOD, CAT, and GPX. This suggests that the CNS can initiate its own "defense" against ROS and FR. Thus, our peptides may activate such systems, as well as AP-1 transcription factor, reported in earlier findings to lead to "repair" (growth) of injured cells.

Animals↗
PubMed2004

Grouping solvents by statistical analysis of solvent property parameters: implication to polymorph screening.

The success rate of discovering new polymorphs by crystallization from solution may be increased if solvents with diverse properties are used during initial polymorph screening. In this study, eight solvent parameters, including hydrogen bond acceptor propensity, hydrogen bond donor propensity, polarity/dipolarity, dipole moment, dielectric constant, viscosity, surface tension and cohesive energy density (equal to square of solubility parameter), of 96 solvents were collected. Using the cluster statistical analysis of the parameters, these 96 solvents were separated into 15 solvent groups. Such solvent groups may provide guidelines for the judicious choice of solvents with diverse properties for polymorph screening.

Chemistry, Pharmaceutical↗
PubMed2004

Co-administration of a DNA vaccine encoding the prostate specific membrane antigen and CpG oligodeoxynucleotides suppresses tumor growth.

BACKGROUND: Prostate-specific membrane antigen (PSMA) is a well characterized prostate-specific tumor associated antigen. Its expression is elevated in prostate carcinoma, particularly in metastatic and recurrent lesions. These observations suggest that PSMA can be used as immune target to induce tumor cell-specific recognition by the host and, consequently tumor rejection. We utilized a DNA-based vaccine to specifically enhance PSMA expression. An immune modulator, such as CpG oligodeoxynucleotides which promote Th1-type immune responses was combined to increase the efficacy of tumor recognition and elimination. METHODS: A eukaryotic expression plasmid pCDNA3.1-PSMA encoding full-length PSMA was constructed. C57BL/6 mice were immunized with endotoxin-free pCDNA3.1-PSMA alone or in combination with CpG oligodeoxynucleotides by intramuscular injection. After 4 immunizations, PSMA specific antibodies and cytotoxic T lymphocyte reactivity were measured. Immunized C57BL/6 mice were also challenged subcutaneously with B16 cells transfected with PSMA to evaluate suppression of tumor growth. RESULTS: Vaccine-specific cytotoxic T lymphocytes reactive with B16 cells expressing PSMA could be induced with this treatment schedule. Immune protection was observed in vaccinated mice as indicated by increased tumor growth in the control group (100%) compared with the groups vaccinated with DNA alone (66.7%) or DNA plus CpG oligodeoxynucleotides (50%) respectively. Average tumor volume was smaller in vaccinated groups and tumor-free survival time was prolonged by the vaccination. CONCLUSION: The current findings suggest that specific anti-tumor immune response can be induced by DNA vaccines expressing PSMA. In addition, the suppression of in vivo growth of tumor cells expressing PSMA was augmented by CpG oligodeoxynucleotides. This strategy may provide a new venue for the treatment of carcinoma of prostate after failure of standard therapy.

Journal Article↗
PubMed2004

Model development and numerical simulation of electric-stimulus-responsive hydrogels subject to an externally applied electric field.

Based on a multi-phasic mixture theory with consideration of ionic diffusion and convection, a multi-physic model, called the multi-effect-coupling electric-stimulus (MECe) model, is developed for simulation of responsive behavior of the electric-sensitive hydrogels when they are immersed into a bathing solution subject to an externally applied electric field. In the developed model, with chemo-electro-mechanical coupling effects, the convection-diffusion equations for concentration distribution of diffusive ions incorporate the influence of electric potential. The electroneutrality condition is replaced by the Poisson equation for distribution of electric potential. The steady and transient analyses of hydrogel deformation are easily carried out by the continuity and momentum equations of the mixture phase. Further, the computational domain of the present model covers both the hydrogel and the surrounding solution. In order to solve the present mathematical model consisting of multi-field coupled nonlinear partial differential governing equations, a hierarchical iteration technique is proposed and a meshless Hermite-Cloud method (HCM) is employed. The steady-state simulation of the electric-stimulus responsive hydrogel is numerically conducted when it is subjected to an externally applied electric field. The hydrogel deformation and the ionic concentrations as well as electric potentials of both the hydrogel and external solution are investigated. The parameter influences on the swelling behaviors of the hydrogel are also discussed in detail. The simulating results are in good agreement with the experimental data and they validate the presently developed model.

Biosensing Techniques↗
PubMed2004

[Liver transplantation for hepatocellular carcinoma: a report of 60 cases].

OBJECTIVE: To evaluate the role of orthotopic liver transplantation (OLT) in treatment of hepatocellular carcinoma (HCC) and the selection of recipients. METHODS: OLT was performed in 60 patients with HCC at Organ Transplantation Centre of the First Affiliated Hospital of Sun Yat-sen University between September 1993 and September 2002. Medical records were retrospectively analyzed with regard to the response to OLT and survival. RESULTS: One-month, 1, 2, 3-year survival rate of 23 liver transplant performed from September 1993 to July 2002 were 73.9%, 60.9%, 43.5% and 29.0%, respectively. One-month, 1, 2-year survival rate of 37 liver transplant performed from August 2000 to September 2002 were 89.2%, 75.8% and 61.2%, respectively. One-month survival rate was significantly greater in the patients with a preoperative liver function of Child A or B than Child C (P < 0.05). One-month, 1, 2, 3-year survival rate of small HCC (single tumor 5 cm diameter, n = 41) were 84.2%, 76.6%, 65.6%, 65.6% and 82.9%, 63.1%, 46.7%, 37.4%, respectively. The median survival of large HCC was 18.0 months and mean survival of small HCC was 29.6 months, respectively. The recurrence rate of small HCC and large HCC were 15.8% and 27.7%, respectively. There was no significant difference between the cumulative survival of small HCC and large HCC. The quality of life of patients with long-term survival was good. CONCLUSIONS: HCC associated with cirrhosis can be effectively treated by OLT on condition that no extrahepatic spread and no vascular involvement. OLT is recommended for treatment of small HCC combined with liver cirrhosis, meanwhile, OLT performed in the partial large HCC still is reasonable at the present time.

Adult↗
PubMed2004

Differential expression patterns of the hox gene are associated with differential growth of insect hind legs.

Diversification of leg appendages is one of the hallmarks of morphological evolution in insects. In particular, insect hind (T3) legs exhibit a whole spectrum of morphological diversification, ranging from uniform to extremely modified. To elucidate the developmental basis of T3 leg evolution, we have examined the expression patterns of two homeotic genes, Ultrabithorax and abdominal-A (collectively referred to as UbdA), in a broad range of species. First, our results show that UbdA expression in hemimetabolous insects is localized only in specific T3 leg segments undergoing differential growth (compared to their foreleg counterparts). In contrast, in basal hexapod and insect lineages, the absence of the UbdA signal coincides with uniform leg morphology. The same situation exists in first instar larvae of holometabolous insects, in which absence of UbdA expression in the embryonic T3 legs is associated with the lack of larval T3 leg diversification. Second, there is a clear difference in the timing of expression between species with greatly enlarged T3 leg, such as crickets and grasshoppers, and species that exhibit more moderate enlargement of hind legs, such as mantids and cockroaches. In the former, the UbdA expression starts much earlier, coinciding with the elongation of T3 limb buds. In the latter, however, the UbdA expression starts at much later stages of development, coinciding with the establishment of distinct leg segments. These results suggest that diversification of insect hind legs was influenced by changes in both the spatial and temporal regulation of the UbdA expression.

Animals↗
PubMed2004

Pressure-dissociable reversible assembly of intrinsically denatured lysozyme is a precursor for amyloid fibrils.

Although a diversity of proteins is known to form amyloid fibers, their common mechanisms are not clear. Here, we show that an intrinsically unfolded protein (U), represented by a disulfide-deficient variant of hen lysozyme with no tertiary structure, forms an amyloid-like fibril after prolonged incubation. Using variable pressure NMR along with sedimentation velocity, circular dichroism, and fluorescence measurements, we show that, before the fibril formation, the protein forms a pressure-dissociable, soluble assemblage (U'(n)) with a sedimentation coefficient of 17 S and a rich intermolecular beta-sheet structure. The reversible assemblage is characterized with a Gibbs energy for association of -23.3 +/- 0.8 kJ.mol(-1) and a volume increase of 52.7 +/- 11.3 ml.mol(-1) per monomer unit, and involves preferential interaction of hydrophobic residues in the initial association step. These results indicate that amyloid fibril formation can proceed from an intrinsically denatured protein and suggest a scheme N <==>U <==>U'(n)-->fibril as a common mechanism of fibril formation in amyloidogenic proteins, where two-way arrows represent reversible processes, one-way arrow represents an irreversible process, and N, U, and U'(n)represent, respectively, the native conformer, the unfolded monomeric conformer, and the soluble assemblage of unfolded conformers.

Amyloid↗