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Biomedical subjects

H Li

Publications and source records attributed to H Li.

At least 451 records · Page 25Linked to original sources
PubMed2001

[Study on the dynamic changes of retinoblastoma gene of SO-Rb50 cell line].

PURPOSE: To study the dynamic changes of Retinoblastoma Gene of SO-Rb50 cell line. METHODS: 1) Southern blot hybridization was used to analyse the tumor cell DNA of 327th passage of SO-Rb50 cell line. 2) A promoter and 27 exons of Rb gene were screened exon-by-exon by using PCR-SSCP at 415th and 713th passages of SO-Rb50 cell line. 3) Three cell cloning strains named as MC2, MC3 and MC4 were isolated by single cell cloning technique from the SO-Rb50-775, and mutation of Rb gene were also screened exon-by-exon by using PCR-SSCP-HA in MC2-11, MC3-11, MC4-11 and MC3-138. RESULTS: The 3.5 Kb, 2.9 Kb and 1.0 Kb bands were deleted in the DNA of SO-Rb50-327 tumor cells, showing the deletion of Rb gene in SO-Rb50 cell line. Exon23 of 451th passage cells decreased one band; but exon 25 of 713th passage cells decreased two bands, indicating that exon 25 had new mutation. PCR-SSCP-HA analysis of exon24 showed that MC4-11 and MC3-138 had abnormal bands, but MC2-11 and MC3-11 weren't found mutation of Rb gene. This result suggested that new mutation occurred to exon24 of MC3 during a long-term culture in vitro. CONCLUSION: Retinoblastoma gene mutation of SO-Rb50 cell line had dynamic changes during a long-term culture.

Exons↗
PubMed2001

[Effect of experimental infection with Schistosoma japonicum on the pregnancy of mice].

OBJECTIVE: To understand the effect of Schistosoma infection on the gestation in mice. METHODS: Female mice infected with Schistosoma japonicum cercariae, and mated with male mice (uninfected) at 40 d and 100 d post-infection, the changes during pregnant period and the growth of offspring were observed until birth. The serum level of estradiol and progesterone of the infected mice was measured by RIA at oestrus. RESULTS: The level of estradiol and progesterone, and the pregnant rate were much lower in schistosome infected group than that of the control. The rate of abortion, the mortality of pregnant mice and the death rate due to abortion of infected mice increased significantly. The mortality increased with the time of merging male and female mice in one cage prolonged. The body weight and length of the offspring in both infected and control groups were found no significant difference. CONCLUSION: The results revealed that schistosome infection may suppress estradiol and progesterone secretion, decrease the rate of pregnancy, and that it may also increase the complications and mortality during the gestation periods.

Animals↗
PubMed2001

[Application of dot immunogold filtration assay in antibody detection for cysticercosis].

OBJECTIVE: To detect serum antibody of cysticercosis by dot immunogold filtration assay for establishing a diagnostic kit for cysticercosis patients. METHODS: Cyst fluid of cysticercus of Taenia solium after dialysis was used as diagnostic antigen in dot immunogold filtration assay and enzyme-linked immunosorbent assay to detect the serum antibody in patients with cysticercosis. Samples to be detected included 71 sera from patients with cysticercosis, 90 sera from healthy people, 20 sera from patients with other parasitic infections or brain tumor. RESULTS: The sensitivity and specificity of dot immunogold filtration assay were 90.1%(64/71) and 95.6%(86/90), respectively. No positive reaction was recorded in cases with other diseases except one serum from a patient with brain tumor. The coincidence rate between dot immunogold filtration assay and enzyme-linked immunosorbent assay was 94.4% (152/161). CONCLUSION: Dot immunogold filtration assay showed promising result for the diagnosis of cysticercosis.

Animals↗
PubMed2001

[Effect of huancongdan capsule on lipoprotein, apolipoprotein and serum immunoglobulin in vascular dementia patients].

OBJECTIVE: To probe into the effect of Huancongdan capsule (HCDC) on the vascular dementia (VD) related factors, including lipoprotein, apolipoprotein (apo) and serum immunoglobulin. METHODS: Fifty-two patients of VD were divided into the HCDC group (27 patients, treated with HCDC) and the control group (25 patients, treated with Naofukang). Changes of related parameters were observed. RESULTS: The effects in lowering triglyceride and total cholesterol and elevating high density lipoprotein cholesterol in the HCDC group were superior to those in the control group (P < 0.01 or P < 0.05), but the effect in lowering low density lipoprotein cholesterol was similar in the two groups (P > 0.05). Compared with data before treatment, in the HCDC group after treatment, the levels of serum apoA1 increased, and serum apoB100, IgA, IgG and circulating immune complex decreased significantly (P < 0.05 or P < 0.01), but the change of apoE level was insignificant (P > 0.05). CONCLUSION: Through adjusting lipid metabolism, HCDC could improve blood rheologic characteristics, promote cerebral blood flow, improve the oxygen carrying capacity of blood to prevent and treat VD. One of its mechanisms is increasing apoA1 and decreasing apoB100 levels, preventing and improving atherosclerosis and reducing damage of vascular endothelial cells, the another may be its action in improving immune function.

Aged↗
PubMed2001

[Effects of laser welding on ceramic fused to metal].

OBJECTIVE: This study was aimed to investigate the bonding effect of laser welding on ceramic fused to metal. METHODS: Ten laser welded CW-PA ceramo-alloy rods were fused with porcelain at fusion zone. The porcelain-metal bond strength was measured with pull-through test. SEM examination and EDAX analysis were performed. Ten non-welded CW-PA ceramo-alloy pull-rod plates were used as comparison. RESULTS: The results showed that the bond strength of laser welded sample was 41.32 +/- 6.69 MPa, approaching to 45.71 +/- 9.98 MPa of the non-welded sample (P > 0.05). The microscope displayed the interface compacted union of the two phase boundary. There was no change in the elements and their ratio at the fusion zone. CONCLUSION: These results indicate that laser welding does not affect ceramic fused to metal.

Dental Porcelain↗
PubMed2001

[Subtotal laryngectomy reconstructed by platysma myocutaneous flaps].

OBJECTIVE: To study the feasibility, surgical techniques and the results of laryngeal function preservation during subtotal laryngectomy in laryngeal carcinoma. METHODS: A retrospective review was made of 13 patients treated by subtotal laryngectomy and laryngeal reconstruction from 1991 to 1996. Eleven patients were male and 2 were female. The age ranged from 46 to 72 years, with a mean of 53.25. All cases were of stage IV. The essence of this operation is to reconstruct the new larynx with two platysma myocutaneous flaps following subtotal laryngectomy. RESULTS: The success rate of voice rehabilitation was 100%. Among them, the acceptability rating scores in 11 cases were 7 and the intelligibility scores ranged from 95% to 98%. The other two cases had acceptability 5 and intelligibility form 90% to 94%. The three-year survival rate was 84.6% (11/13), 5-year survival rate was 76.9% (10/13). CONCLUSION: This form of laryngeal reconstruction in subtotal laryngectomy is helpful to restore laryngeal function and decrease the rate of total laryngectomy. The procedure is easy, safe and applicable to patients treated by subtotal laryngectomy.

Aged↗
PubMed2001

[Surgery of substernal goiter].

OBJECTIVE: To study the surgical approaches and operative techniques for substernal goiter. METHOD: A retrospective study of 27 cases with substernal thyroid nodules was made in our hospital. RESULT: The operations on 27 patients with substernal nodules have been successfully carried out. Among them, 10 were goiters, 9 adenomas, 4 malignancy and 4 were thyroid cancer metastasizing to paratracheal or substernal nodes. Resection via cervical collar incision was adequate in 23 cases. Three thyroid cancers with paratracheal node metastasis were completely resected by sternotomy and only one thyroid cancer with paratracheal and substernal nodes metastasis was resected by combined thoracotomy and cervical collar incision. CONCLUSION: Resection via cervical collar incision for all retrosternal thyroid nodules were advised. The preliminary experience with this procedure suggests that it has some advantages in the management of substernal goiter, including: 1. ease of operation compared to both sternotomy and thoracotomy; 2. relatively low morbidity; 3. safe and reliable.

Adult↗
PubMed2001

[Intact-bridge tympanomastoidectomy procedure: a reasonable option in the surgery of chronic otitis media and mastoiditis with cholesteatoma and/or granulation tissue].

OBJECTIVE: To study and evaluate a surgical option for the treatment of otitis media and mastoiditis with cholesteatoma and/or granulation tissue. METHODS: The procedure is called intact-bridge tympanomastoidectomy (IBM). There are some modifications for the treatment of patients suffered from chronic otitis media and mastoiditis with cholesteatoma and/or granulation tissue. The features of IBM include: 1. the aditus, mastoid and attic opened and the intractable pathological tissues eradicated thoroughly. 2. the posterior tympanal space opened through the facial recess if necessary. 3. a widened middle ear space by lowering bony bridge established. 4. the adults blocked. 5. immediate or staging tympanoplasties conducted according to the conditions of mucosa in the tympanum. RESULTS: The modified IBM procedure was performed on 62 ears from 61 cases. The follow-up has been 12-38 months and more than two years in 51 ears. The dry ear was obtained within 5-13 weeks with an average of 6 weeks. In 24.2% of ears the air-bone gap(ABG) was 20dB HL or less and within 21-30 dB HL in 41.9% of ears, the ABG over 31 dB HL was 16.1%. CONCLUSION: Our results indicate that IBM procedure fulfills the desired purposes of both open- and close-cavity techniques, the thorough eradication of diseased tissue allow to get a dry ear and restoration of hearing. IBM, therefore, is a reasonable choice for the surgery of otitis media and mastoiditis with cholesteatoma and/or granulation tissue.

Adolescent↗
PubMed2001

[Effect of transduction bax gene on experimental nasopharyngeal carcinoma].

OBJECTIVE: To evaluate the effect of transduction bax gene on nasopharyngeal carcinoma (NPC). METHODS: The transduced bax gene was mediated by Dosper lipidsome to the HNE-1 cell lines, and confirmed by immunofluorescent stain. The apoptosis of the cell lines was studied by MTT stain and flow cytometry and the growth of implanted tumor in naked mouse after local injection of bax geneobserved. RESULTS: Instantaneous expression of bax gene in HNE1 cell lines was testified by immunofluorescent stain after transduction for 48 hours, the apoptotic index were 10.7% and 69.4% for pre- and post-transduction, respectively. MTT stain showed the values of A in 490 nm after transduction to be 2.004(36 h) and 1.902(48 h). The diameter of implanted tumor mass was (1.8 +/- 0.64) cm and (3.0 +/- 0.44) cm in experimental and control groups, respectively. CONCLUSION: The transduction bax gene can enhance the apoptosis of HNE1 cell lines and prevent growth of implanted tumor.

Animals↗
PubMed2001

[Expressions of vascular endothelial growth factor and basic fibroblast growth factor in nasal polyp and its role].

OBJECTIVE: To evaluate the role of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor(bFGF) in the pathophysiology of nasal polyp. METHODS: Thirty-nine patients with nasal polyp were divided into two groups: group A(representing type 1 and type 2 phase 1-2) and group B (representing type 2 phase 3 and type 3). The expression of VEGF and and bFGF in both groups were studied with immunohistochemical method. RESULTS: VEGF and bFGF were not detected in norms. The detection rates of VEGF and bFGF were 59%, 41%, and 71%, 80% in group A and group B respectively. The positive rate and the number of positive cells were higher significantly in group B than that in group A. VEGF and bFGF were located mainly in the inflammatory cells and epithelial cells around the basilar membrane and inflammatory cells and endothelial cells around the vessel. CONCLUSIONS: The overexpression of VEGF and bFGF in nasal polyp may contribute to the growth of vessels, accumulation of inflammatory cells, as a result, to enhance the development of nasal polyposis. This phenomenon maybe an important histological mark distinguishing ordinary polyp from polyposis.

Adolescent↗
PubMed2001

[Effects of lovastatin combined with cyclosporine A on cultured human peripheral blood mononuclear cells proliferation, cytokines expression and cytotoxicity].

OBJECTIVE: To investigate the effects of lovastatin combined with cyclosporine A (CsA) on cultured human peripheral blood mononuclear cells (PBMC) proliferation, cytokines expression and cytotoxicity in vitro. METHODS: The PBMC was isolated by using Ficoll-Hypague density gradient centrifugation method and its viability was evaluated with LDH-release assay. The effects of lovastatin combined with CsA on cultured PBMC proliferation and cytotoxicity were observed in 3H-TdR incorporation assay. The levels of supernatant IFN-gamma and IL-2 were quantitated respectively with RIA and ELISA-SPOT assay. The IL-2 and IFN-gamma mRNA expressions were determined by RT-PCR. RESULTS: Both lovastatin and CsA inhibited PBMC proliferation, expression of IL-2 and IFN-gamma, and NK cell cytotoxicity in a dose-dependent manner. Combination of the two drugs produced synergism. CONCLUSION: Statins combined with cyclosporine A have a synergic effect and can delay the incidence and development of allograft rejection and prolong the graft life-span in animal models and clinical trials.

Cell Division↗
PubMed2001

[Development of a canine adenovirus type 1 vaccine strain E3-deleted based expression vector].

OBJECTIVE: To evaluate canine adenovirus type 1 vaccine strain (Cannaught Laboratory Limited, CLL) as recombinant vaccine and gene transfer vector. METHODS: Recombinant virus CLLEGFP which contains enhanced green fluorescent protein(EGFP) reporter gene was constructed. CLLEGFP was used to infect various human derived cell lines(293, Hela, CO, SW, Hep-2 and CAM) by inoculating intraperitoneally(i.p.), intravenously(i.v.) and intramuscularly (i.m.) to Kunming mice other than oral administration. Various tissue samples of the mice were collected at multi-time point for observing EGFP green fluorescence. Anti-EGFP antibodies were detected by Western blot analysis in the sera after 4 weeks. RESULTS: CLLEGFP can infect various human derived cell lines and express EGFP. EGFP green fluorescence were observed in liver tissue cells after i.p. transducing 3 days. All immune inoculation ways above could induce Kunming mice producing anti-EGFP antibodies which were identified by Western blot analysis. CONCLUSIONS: These results indicate that CLL possess powerful potential as recombinant vaccine and gene transfer vector.

Adenoviruses, Canine↗
PubMed2001

[Tuberculosis in patients with chronic renal failure undergoing hemodialysis].

OBJECTIVE: To improve the level of early diagnosis and outcome of tuberculosis (TB) in patients with chronic renal failure on regular hemodialysis (HD). METHODS: Thirteen cases among 306 patients undergoing HD from January 1995 to May 2000 were identified, and the clinical presentations, diagnostic procedures and management were analyzed. RESULTS: The incidence of TB in HD patients was 4.2%. The extrapulmonary TB is common, accounting for 76.9%. The main site of TB was pleural in 4 (30.8%) patients. Most of patients were sensitive to anti-TB agents with the total effective rate of 84.6%. CONCLUSIONS: The TB should be diagnosed carefully and treated promptly if suspected in patients with CRF during the period of HD.

Adult↗
PubMed2001

[Clinical significance of matrix metalloproteinase-2 expression in patients with epithelial ovarian tumor].

OBJECTIVE: To investigate the relationship between the expression of matrix metalloproteinase-2 (MMP-2) and clinical characteristics of patients with epithelial ovarian tumor. METHODS: Reverse transcriptase-ploymerase chain reaction and immunohistochemistry were used to detect the expression of MMP-2 in 41 epithelial ovarian cancer and 26 ovarian benign tumors. Western blot analysis was used to examine proMMP-2 and active MMP-2 in these tumors. RESULTS: The expression of MMP-2 gene and protein was not significantly higher in malignant tissues than that in benign ones. The positive percentage of active MMP-2 expression in epithelial ovarian cancer was 71% and 42% in ovarian benign tumor (P < 0.05). The positive percentage of active MMP-2 in stage IlI and IV epithelial ovarian cancer was significantly higher than in stage I and II epithelial ovarian cancer (P < 0.05). The positive percentage of active MMP-2 in progressive patients with epithelial ovarian cancer was significantly higher than in patients in remission (P < 0.05). CONCLUSIONS: MMP-2 gene and protein were generally expressed in epithelial ovarian tumor. There was a significant correlation between active MMP-2 and the invasion and metastasis of epithelial ovarian cancer. Active MMP-2 is a prognostic indicator in patients with epithelial ovarian cancer.

Biomarkers, Tumor↗
PubMed2001

[Clinical value of preserving intercostal-brachial nerve during breast cancer operations].

OBJECTIVE: To study the value of preserving intercostal-brachial nerve during axillary dissection for breast neoplasms. METHODS: From June 1996 to December 1997, stage I, II breast cancer patients were divided into experimental group (n = 45) and control group (n = 60) respectively. The intercostal-brachial nerve was preserved in the experimental group and not in the control group. Both were followed up after operations. RESULTS: The postoperation morbidity of arm sensory disturbance was 7.1% in the experimental group, which was significantly different from that of the control group(63.3%, chi2 = 34.69, P < 0.01). No difference was noted in the recurrence rate between the two groups. CONCLUSIONS: Preserving intercostal-brachial nerve may significantly decrease the morbidity of postoperation arm sensory disturbance during axillary dissection for stage I, II breast cancer patients.

Adult↗
PubMed2001

[An epidemiological study of spongiform leucoencephalopathy among heorin abusers].

OBJECTIVE: To understand the distribution and related risk factors of heroin spongiform leucoencephalopathy among drug users in coastland of Guangdong Province. METHODS: A cross-sectional study was conducted in four thousand four hundred and twenty eight drug users from eighteen detoxification organizations in six cities on coastland of Guangdong, using clustered random sampling methods. The six cities are Chaoyang (714), Heyuan (462), Shantou (572), Huidong (1286), Guangzhou (871) and Zhanjiang (523) and heroin abuse was considered serious in these cities. Questionnaire was used to collect the data on sex (man 3632, 82 percent; woman 795, 18 percent), age (minimum 15y, maximum 54y), duration of using heroin (minimum 1 month, maximum 150 months), daily dosage (minimum 0.02 g, maximum 6.0 g) and manner of using heroin. In addition, the neurological examination was taken in all of them and cerebral MRI was carried out in those with signs of cerebellar ataxia. RESULTS: Results showed that the total incidence of heroin spongiform leucoencephalopathy in six cities is 3.16 per thousand. Poisson regression analysis showed that the incidence was related to residential areas. In comparison with other cities, there are higher incidences in Chaoyang and Heyuan. Our investigation also showed that all the patients with this disease used heroin by inhaling the pyrolysate. The incidence of heroin spongiform leucoencephalopathy was unrelated to the daily inhaling amount of heroin and the duration of inhaling heroin. No differences could be observed between the groups of different age and sex. CONCLUSIONS: Spongiform leucoencephalopathy after inhalation of heroin is a rare complication and has never been reported in mainland of China before. The lesions are symmetrical and spongiform, but not necrotic and the cerebellum is invariably involved--a feature consistent with the clinical presentation that begins with ataxia. Cerebral CT showed symmetrical non-enhancing hypodense areas in both cerebellar hemispheres. Cerebral MRI showed the corresponding areas with decreased signal intensity on T1 weighted images and increased signal intensity on T2 weighted images. There was no contrast enhancement. When it occurs, several cases are affected as a small epidemic. It is suggested that the aetiology is related to the heroin batch and could perhaps be a toxic effect of a substance which came from heroin pyrolysis.

Administration, Inhalation↗
PubMed2000

Intracellular labeling study of neurons in the superficial part of the magnocellular layer of the medullary dorsal horn of the rat.

Morphology and electrical membrane properties of neurons in the superficial part of the magnocellular layer of the rat medullary dorsal horn (MDH: caudal subnucleus of the spinal trigeminal nucleus) were examined by using horizontal slice preparations. Intracellular recording and biocytin-injection combined with histochemical and immunohistochemical staining were done. Twenty-four neurons were examined successfully and classified into projection neurons (PNs) and intrinsic neurons (INs). The PNs were further divided into type I PNs (I-PNs) and type II PNs (II-PNs). The I-PNs sent axons to the medullary reticular formation; the II-PNs sent axons to the interpolar subnucleus of the spinal trigeminal nucleus but had no axons extending to the medullary reticular formation. The INs that sent no axons to the brain regions outside the MDH were also divided into small INs with spiny dendrites (INSSs) and large INs with aspiny dendrites (INLAs). The dendritic fields of the PNs extended to laminae I and II of the MDH and occasionally further to the spinal tract of the trigeminal nerve, whereas those of the INs were confined within the magnocellular layer of the MDH. The axonal branches of each IN formed a dense axonal mesh around the cell body of the parent neuron. Although the main bodies of the axonal fields of the INs were located in the magnocellular layer, some axonal branches extended to laminae I and II of the MDH. Immunoreactivity for NK1 receptor (substance P receptor) was found in approximately half of the PNs but not in the INs. Although no strong correlation was found between morphology and electrical membrane properties, there were some differences in electrical properties among the morphologically classified neuron groups, e.g., hyperpolarizing sag was observed in some PNs but not in the Ins; inward rectification was observed in some of the INSSs and INLAs but not in the PNs; the slow ramp depolarization and the slow afterdepolarization were observed in all INSSs examined but not in the PNs or INLAs.

Animals↗