Biomedical subjects

B Li

Publications and source records attributed to B Li.

At least 181 records · Page 10Linked to original sources

PubMed2001

[Reconstruction of heel: long-term follow up of 12 cases].

OBJECTIVE: To study long-term follow up result of fibula transplantation to reconstruct partial or complete defect of the heel. METHODS: Heel defects were reconstructed by means of reverse transferring of combined vascular pedicled fibulaflap. The calcaneus was repaired by two segments of the fibula. Skin defects were covered by skin flap, and sensation was restored by anastomosing the sural nerve and medial pedal nerve. The residual cavity was filled by muscles surrounding the fibula to reconstruct the appearance of foot. RESULTS: Four patients with complete heel defect and 8 with partial defect were operated on successfully. Two to 13 years(average 5.2 years) follow-up showed that the function and appearance of foot were normal and adaptive changes happened in the tissue of foot. The fibula was getting into a real cal caneous gradually. Besides this, the skin was thickened and the sensation was restored with the two-point discrimination of 0.8 to 3.0 cm. All patients resumed physical work. Comprehensive evaluation revealed that 11 patients were excellent and 1 was good in their functional recovery. CONCLUSION: The results suggested that this operation is ideal for reconstructing heel defect. All kinds of tissues in heel can be reconstructed and more satisfactory function and appearance can be obtained through adaptive heel reshaping along with long-term walk.

Adolescent↗

PubMed2001

[Relationship between cholinesterase, prothrombin activity and albumin and the pathology of the liver].

BACKGROUND: To investigate the relationship between serum cholinesterase, albumin and plasma prothrombin activity and the pathology of the liver in patients with viral hepatitis. METHODS: Totally 135 patients diagnosed as chronic hepatitis, cirrhosis and/or severe hepatitis with needle biopsy of liver were enrolled in this study. Serum cholinesterase and albumin of the patients were detected with enzyme rate method; meanwhile, their plasma prothrombin activity was detected with turbidimetry test. RESULTS: The percentage of decrease of the level of serum cholinesterase was higher than that of albumin and plasma prothrombin activity in chronic mild and moderate hepatitis; the level of serum cholinesterase, albumin and plasma prothrombin activity decreased gradually followed by the exacerbation of inflammatory reaction (P<0.001) and by the elevation of degree of fibrosis of the liver (P <0.001) their correlation coefficient was 0.720 to 0.778 (P<0.001). CONCLUSION: The level of serum cholinesterase could better a nd more sensitively reflect the synthetic function and the damage of the pathology of the liver than that of albumin and plasma prothrombin activity could do, they all negatively correlated with the pathology of the liver.

Adolescent↗

PubMed2001

[Study of deletion and mutation of p16 gene in primary hepatocellular carcinoma].

OBJECTIVE: To investigate the role the deletion and mutation of p16 gene plays in the pathogenesis of human primary hepatocarcinoma. METHODS: Thirty-one cases of human hepatocarcinoma, 31 cases of adjacent noncancerous liver cirrhosis and the leukocytes of 8 normal human subjects were analyzed for deletion and mutation in p16 gene exons 1, 2 and introns 1, 2 with comparative multiple PCR and PCR-SSCP. RESULTS: Deletion of p16 gene exon 1 and partial intron 1 was found in 4 of 31 cases (13/%). No deletion of exon 2 or intron 2 was found. Three patterns of p16 gene intron 1 and 18 bp-flanking sequence in exon 2 at SSCP analysis were observed in hepatocellular carcinoma and corresponding adjacent noncancerous cirrhosis, and two patterns were found in human normal leukocyte DNA. No aberrant single strand at SSCP in p16 gene exon 1 or most part of exon 2 or intron 2 was detected. CONCLUSION: Low frequency of deletion and rare mutation of p16 suppressor gene occurred in hepatocellular carcinoma.

Carcinoma, Hepatocellular↗

PubMed2001

[Study on psychoprophylaxis and monoamines neurotransmitter of patients with burning mouth syndrome].

OBJECTIVE: Burning mouth syndrome (BMS) is a chronic ache disease, usually occurring in middle aged and old women. This study sought to understand the psychopathologic aspect and monoamines neurotransmitters in the plasma of the patients with BMS. METHODS: Thirty cases were selected (26 females, 4 males); 30 normal control subjects were similar to the BMS cases on age and sex. All subjects were required to complete the Eysenck personality questionnaire (EPQ), and the Self-report Symptom Inventory, Symptom Check List-90 (SCL-90) questionnaire. In case a subject's L (lie) score exceeded 50, she (he) would be removed from the test. 2 ml of blood was drawn from the subject under restine conditions with a fast in the morning to examine norepinephrine and epinephrine contents by high efficient liquid chromatography. Chi-square test, analysis of variance and t'-test were performed. RESULTS: The BMS group had higher scores of nervousness (N) and poikilergasia (P) and lower score of extro/introversion (E) as compared with the control (P < 0.05). The personality types in BMS group were focused on introversion and instability, but in the control group the types were focused on extroversion and stability (P < 0.05). The scores of 9 emotional factors of BMS group were significantly higher than those of the control group (P < 0.05), which indicated that the BMS patients had suffered from serial psychic disorders. The level of plasma norepinephrine in the BMS patients was higher than that of the control (P < 0.01). CONCLUSION: The personality of BMS patients raised body response to harmful stimulations, and obvious psychic disorders in the patient may cause the functional disorders in central and sympathetic nervous systems, which may be associated with BMS' occurrence.

Adult↗

PubMed2001

[p53 mutation in lung cancer in Gejiu and Xuanwei regions of Yunnan Province].

OBJECTIVE: To incidence rates of lung cancer among tin miners in Gejiu and among peasants in Xuanwei are higher than the average incidence rate in Yunnan Province, and the causes of the disease in these two regions have been preliminarily clarified. This study was directed to the molecular biological basis of its pathogenesis. METHODS: Twenty-six specimens of the lung cancers of Gejiu tin miners(GTM) and 15 ones of Xuanwei peasants (XP) were examined by single-strand conformation polymorphism analysis of polymerase chain reaction products. RESULTS: Using PCR primers for the most highly conserved region of the p53 including exons 5-8, we have identified p53 mutations in 13 lung cancer tumor DNA samples of GTM and in 4 ones of XP. Nucleotide sequencing of one of the exon 5 mutations of GTM indicated that there was a C to T transition, which resulted in substitution of Val for Ala at amino acid 135, and there was an AAC to TTC transertion in the exon 7 of XP, which resulted in substitution of Phe for Asn at amino acid 247. CONCLUSION: p53 mutation is a frequent incident in lung cancer of GTM and XP, and two new mutation sites were found in p53 gene, which have not been reported before now. There was no statistically significant correlation between the detection of p53 mutation and the patient's age, sex, mining history and histologic type of the cancer.

China↗

PubMed2001

[Phospholipase activities of Candida albicans isolates from oral pre-malignant lesions and oral cancers].

OBJECTIVE: The aim of this study is to compare activities of phospholipase of Candida albicans isolates from oral cavities of two groups of patients, including oral pre-malignant lesions and oral cancers. METHODS: A total of 55 isolates, including oral pre-malignant lesions (21), oral cancers (15), and normal health control (19), were studied using the precipitate zone assay on the egg yolk agar. RESULTS: No significant difference was found in phospholipase activities between these isolates from normal controls and oral pre-malignant lesions, while the activities of phospholipase of isolates from oral cancers were higher than those of the normal controls. CONCLUSION: Candida albicans may play different roles in different manners in these two closely related diseases.

Candida albicans↗

PubMed2001

[The examination of DNA repair capacity in the patients with oral precancerous lesion].

OBJECTIVE: The occurrence of oral precancerous lesion is related with not only carcinogenic environmental factors but also some self-regulating mechanisms. The genetic heredity factors determine individual's DNA repair capacity. The study is attempted to investigate the change of DNA repair capacity of the patients with the precancerous lesion. METHODS: The study is conducted in 16 pairs of oral precancerous lesion and normal controls by using host cell reactivation assay, while some dangerous factors such as smoking, alcohol intaking and family history of cancers are also recorded. RESULTS: The host cell reactivation in the patients with precancerous lesion is lower than that of normal controls (P < 0.05) and is shown to be an independent risk factor in the occurrence of oral precancerous lesion (OR: 3.25 95% CI = 1.01-10.49). CONCLUSION: The host cell reactivation is likely to be a helpful indicator for predict prognosis of cancer for the individuals with highly genetic sensitivity to cancer.

DNA Repair↗

PubMed2001

[A study on the breeding of new Ganoderma varieties by UV induced mutagenesis].

UV induced mutagenesis of Ganoderma's protoplast was carried out. By crude screen and careful screen, we obtained two mutants, 43020# and 43026$, whose dry weight and polysaccharides contents are higher than original strain. Results of continued cultivation for 10 generation on PDA slants and successive tests of shaking bottles, and successive 3 time pilot scale tests at 3 tons, showed that these two mutants are excellent strains with steady properties, high production and high content of polysaccharides. This study has provided a rapid and effective method for breeding of Ganoderma varieties which is suitable to industrial fermentation.

Breeding↗

PubMed2001

[Sequencing of E2 gene and comparison analysis of four strains hog cholera virus (HCV)].

Four cDNA fragments of envelope glycoprotoin E2 gene of SM strain, HCLV strain, F03 strain and F07 strain were amplified respectively with RT-PCR method. The amplified E2 fragments of four HCV strains were all 1273 bp in length by agarose gel electrophoresis. Four E2 fragments were cloned respectively into pGEM-T easy vector. 1273 bp cDNA fragment of Four HCV E2 gene were sequenced and 381 residues amino acid sequence of E2 glycoprotein were deduced. The signal peptide sequence (WLLLVTGA) located in the N-terminal residues 683-690 and the transmenbrane region (TMR) sequence located in the C-terminal residues 1031-1063 of Four E2 gene were highly conserved and hydrophobic region. The conserved sequence among the E2 protein of pestiviruses, RYLASLH which located in the N-terminal residues 753-759 of domains B and C, was hydrophilic, and none of them were variable among the pestiviruses, and the greatest values of antigenic in all E2 antigenic domain. This suggest that the conserved sequence RYLASLH are involved in E2 epitopes. The number and locations of 15 cysteine residues in E2 are conserved among pestiviruses, suggesting that the structure of this glycoprotein is similar in pestiviruses and the first six cysteines are critical for the correct folding of E2 and essential for all identified epitopes. It is showed epitopes. between HCLV strains and field strains are not variable obviously by analysising the varintion of some main amino acid residuse substitutions of E2 major antigenic domains.

Amino Acid Sequence↗

PubMed2001

[Production and detection of monoclonal anti-idiotype antibodies against Vibrio anguillarum].

Vibrio anguillarum is the pathogenic bacteria of Vibriosis, which is an infectious disease found in various fish species. Seven monoclonal anti-idiotype antibodies(mAb2) were raised against mAb1 4A6. Identification of subgroup showed that 1H5, 1D1, 2B12 and 2F12 belonged to IgG2b, 2H12 and 1H12 to IgG2a and 1E10 to IgG3. The titers of these mAb2 ascites were 1 x 10(-4)-1 x 10(-6). The capacity of the mAb2 to inhibit the binding between mAb1 and antigen was investigated with the competitive inhibition ELISA. The results showed that 1D1, 1E10 1H5 and 2H12 mAb2 were able to inhibit this binding. Another experiment demonstrated that four mAb2(1D1, 1E10, 1H5 and 2H12) might induce Balb/c mice to produce Ab3 and these Ab3 competed the same antigen epitopes with Ab1. These results indicate that mAb2(1D1, 1E10, 1H5 and 2H12) are likely to represent internal image of antigen and belong to Ab2 beta. They might be employed to induce antibodies against pathogenic epitopes of V. anguillarum in vivo so as to gave the safe and effective vaccine.

Animals↗

PubMed2001

[Inhibitory effects of beta-carotene on hepatic cancer cell line SMMC-7721].

The inhibitory effect of beta-carotene on the proliferation of hepatic cancer was studied. Cells from a hepatic cancer cell line SMMC-7721 were incubated in culture media with 20, 40 and 80 mumol/L beta-carotene for 12, 24 and 48 h respectively. MTT test, Trypan blue exclusion test and DNA gel electrophoresis were used. The results of MTT test revealed that beta-carotene (20-80 mumol/L) could inhibit the proliferation of SMMC-7721 cells in a dose-dependent manner. DNA gel electrophoresis showed that the apoptosis of hepatic cancer cells could be induced by beta-carotene (40 mumol/L). It is concluded that the proliferation of hepatic cancer cells inhibited by beta-carotene, probably through interfering DNA metabolism and inducing cell apoptosis.

Antineoplastic Agents, Phytogenic↗

PubMed2001

[Protective effect of total flavonoids of fructus choerospondiatis on adriamycin-induced rat cardiac peroxidation].

OBJECTIVE: To study the protection effect of total flavnoids of Fructus Choerospondiatis (TFFC) on rat cardiac muscle peroxidation in vitro and vivo. METHODS: Adriamycin-induced peroxidation model on rat was adopted. Activities of LDH, AST and CK in rat's serum, activities of SOD, GSH-Px and content of MDA in rat cardiac muscle were determinated. Activity of LDH and content of MDA in cultured suckling rat cardiac cell were also determinated. RESULTS: Compared with normal group, activities of LDH, AST, CK in serum and content of MDA in cardiac muscle on adriamycin group increased (P < 0.05, P < 0.001), activities of SOD, GSH-Px decreased in cardiac muscle (P < 0.001). Activity of LDH and content of MDA in cultured fluid of suckling rat cardiac cell were higher than that of normal group (P < 0.001). To various dosages TFFC groups, activity of LDH, AST, CK in serum and content of MDA in cardiac muscle decreased; activities of SOD and GSH-Px in cardiac muscle increased; activites of LDH and content of MDA in cultured fluid decreased (P < 0.01, P < 0.001). CONCLUSION: TFFC can maintain the integrity of cytomembrane by scavenging free radicals and inhibiting lipid peroxidation, namely, TFFC has an effect of protecting cardiac muscle.

Anacardiaceae↗

PubMed2001

[The effects of quercetin and isorhamnetin on oxidative modification of VLDL induced by Cu2+].

OBJECTIVE: To observe the effects of quercetin(Que) and isorhamnetin (Iso) on the oxidative modification of very low density lipoprotein (VLDL). METHODS: Human VLDL was prepared by one-step ultracentrifuge and oxidized by Cu2+ in vitro; Que and Iso in different concentrations were added to VLDL before incubation with Cu2+. The MDA, vitamin E contents and the activity of superoxide dismutase(SOD) in ox-VLDL were determined. RESULTS: Compared with ox-VLDL group, Que and Iso decreased MDA production in a dependent concentration-manner, Que and Iso also elevated Vit E level and SOD activity markedly. CONCLUSION: This experiment indicates that Que and Iso have similar inhibitory effects on the oxidative modification of VLDL.

Copper↗

PubMed2001

[Scaling the SF-36 in a Chinese population].

OBJECTIVE: To facilitate the cross-cultural comparison, we employed the principles of fuzzy mathematics in scaling the SF-36 in a Chinese population. METHODS: We stratified an urban population according to the age, sex, and occupation, and selected 650 people to participate in the study. A total of 646 valid questionnaires were returned. In the 8 domains of the SF-36, the interval estimation of the scores of different alternative answers of 6 domains which have more than 2 alternative answers were conducted. RESULTS: The fuzzy degrees of most interval estimations were less than 0.5, except 4 estimations in the domain "physical functions". The ordering of the scores of 8 domains was more similar to the original assumption by our scaling criteria than by the US scaling criteria. CONCLUSION: The scaling criteria set in this study is more suitable for use in Chinese population and we suggest that the alternative answers of the domain "physical functions" be simplified to "yes" and "no".

Activities of Daily Living↗

PubMed2001

[Retrospective analysis of supracricoid partial laryngectomy with epiglottis preserved and reconstruction of laryngeal function].

OBJECTIVE: To retrospectively evaluate the curative and functional consequences of supracricoid partial laryngectomy with epiglottis preserved. METHODS: From 1980 to 1996, 78 patients underwent supracricoid partial laryngectomy with the epiglottis preserved. The survival rate and the functional results were analyzed. RESULTS: Overall three-year survival rate was 87.2%(68/78), overall five-year survival rate was 75.6% (59/78), and ten-year survival rate was 21.1% (8/38). All patients resumed normal oral feeding. 97.4% (76/78) achieved tracheal extubation. Respiratory and speaking functions were good. CONCLUSION: Supracricoid partial laryngectomy with epiglottis preserved and reconstruction of laryngeal function not only improved local cancer control, but also preserves laryngeal physiologic function.

Adult↗

PubMed2001

The mechanism of cerebral evoked potentials by repetitive magnetic stimulation of gastrocnemius muscle in Duchenne muscular dystrophy.

OBJECTIVE: To study the features and mechanism of the cerebral evoked potentials by repetitive stimulation of calf muscle in Duchenne muscular dystrophy (DMD) patients with obvious muscular dystrophy and psuedohypertrophy. METHODS: Cerebral evoked potentials by stimulation of calf muscles and somatosensory evoked potentials (SEPs) by the stimulation of posterior tibial nerves at ankle were measured in 10 patients with DMD and 10 normal controls matched with gender and age. The intensity of the magnetic stimulation was at 30% of maximal output (2.1 Tesla, MagPro magnetic stimulator, Dantec) and the frequency was 1 Hz. The low intensity of magnetic stimulation was just sufficient to produce a contraction of the muscle belly underneath the coil. Recording electrode was placed at 2 cm posterior to the Cz, reference to Fpz. The latencies of N33, P38, N48 and P55 and amplitude (P38 - N48) were recorded. SEPs were recorded by routine methods. RESULTS: In normal subjects, the amplitudes of cerebral evoked potentials by magnetic stimulation of calf muscle was 40% lower than that by electrical stimulation of the posterior tibial nerves at ankle. The latency of P38 was 2.9 +/- 2.1 ms longer compared with electrical stimulation of the posterior tibial nerves at ankle. In 6 patients, P38 latency from magnetic stimulation was remarkably prolonged (P < 0.01), and in 4 patients, there was no remarkable response. SEPs evoked by electrical stimulation were normal in all of the patients. CONCLUSION: DMD is an available model for the study of mechanism of cerebral evoked potentials by magnetic stimulating muscle. We can conclude that the responses from magnetic stimulation were produced by muscle input. The abnormal responses in patients may relate to decreased input of muscle by stimulating dystrophic and psedohypertrophic muscle.

Adolescent↗

PubMed2001

[Spectral interferences of rare earth elements observed with a high resolution inductively coupled plasma atomic emission spectrometer. VI. Spectral interferences of lanthanum, terbium, holmium and erbium as matrices].

The spectral interferences of La, Tb, Ho and Er (1,000 micrograms.mL-1, separately) as matrices on the other rare earth elements (REEs, 1 or 5 micrograms.mL-1) were studied with a high resolution ICP atomic emission spectrometer with a grating of 3,600 grooves/mm. Totally 66 analytical lines of 15 REEs were selected as the prominent lines in the spectral interference studies. The overlapping profiles of analytical lines and interference line were obtained by scanning different solutions (blank, analyte, and four REE matrices, individually) within the selected wavelength windows (0.2 nm for each analytical line). Some new spectral lines of La, Tb, Ho and Er were observed. The "best" analytical lines of 14 REEs were recommended based on the Q-values and the true detection limits.

Erbium↗

PubMed2000

Proximity relationships between residue 6 of troponin I and residues in troponin C: further evidence for extended conformation of troponin C in the troponin complex.

Skeletal muscle troponin C (TnC) adopts an extended conformation when crystallized alone and a compact one when crystallized with an N-terminal troponin I (TnI) peptide, TnI(1-47) [Vassylyev et al. (1998) Proc. Natl. Acad. Sci. U.S.A. 95, 4847-4852]. The N-terminal region of TnI (residues 1-40) was suggested to play a functional role of facilitating the movement of TnI's inhibitory region between TnC and actin [Tripet et al. (1997) J. Mol. Biol. 271, 728-750]. To test this hypothesis and to investigate the conformation of TnC in the intact troponin complex and in solution, we attached fluorescence and photo-cross-linking probes to a mutant TnI with a single cysteine at residue 6. Distances from this residue to residues of TnC were measured by the fluorescence resonance energy transfer technique, and the sites of photo-cross-linking in TnC were determined by microsequencing and mass spectrometry following enzymatic digestions. Our results show that in the troponin complex neither the distance between TnI residue 6 and TnC residue 89 nor the photo-cross-linking site in TnC, Ser133, changes with Ca(2+), in support of the notion that this region plays mainly a structural rather than a regulatory role. The distances to residues 12 and 41 in TnC's N-domain are both considerably longer than those predicted by the crystal structure of TnC.TnI(1-47), supporting an extended rather than a compact conformation of TnC. In the binary TnC.TnI complex and the presence of Ca(2+), Met43 in TnC's N-domain was identified as the photo-cross-linking site, and multiple distances between TnI residue 6 and TnC residue 41 were detected. This was taken to indicate increased flexibility in TnC's central helix and that TnC dynamically changes between a compact and an extended conformation when troponin T (TnT) is absent. Our results further emphasize the difference between the binary TnC.TnI and the ternary troponin complexes and the importance of using intact proteins in the study of structure-function relationships of troponin.

Animals↗