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Biomedical subjects

Wei Li

Publications and source records attributed to Wei Li.

At least 397 records · Page 22Linked to original sources

[A study of hemodynamic changes in the arteries of rabbit's eye caused by acute high intraocular pressure].

OBJECTIVE: Using the color Doppler flow imaging (CDFI) to measure and to study the hemodynamic changes of rabbit's retrobulbar artery caused by changes of intraocular pressure (IOP). To provide information for screening of drugs that improves the blood circulation and decrease the IOP. METHODS: This is a self-contrast research performed at the left eye: high IOP was induced, then the hemodynamic changes of rabbit's retrobulbar artery at different IOP stages were observed. RESULTS: Rabbit's ophthalmic artery (OA), ciliary artery (CA), short posterior ciliary artery (SPCA), central retinal artery (CRA) are low resistant artery. When the IOP raised rapidly, the velocity of blood flow became slower and resistance force index became higher. The hemodynamic changes could not return to normal even after the IOP decreased to the normal level. CONCLUSION: A short-term high IOP can influence the hemodynamic pattern of retro-bulbar arteries. Color Doppler flow imaging is a valuable method for monitoring these changes.

Animals↗

[Study on the current situation and influential factors of child neglect among aged 3-6 year-olds in the urban areas of China].

OBJECTIVE: Children aged 3 - 6 years in the urban areas of China were surveyed for the first time to find out the state of child neglect (CN) as well as the major relevant risk factors so as to provide evidence for developing intervention measures. METHODS: 1163 children (of whom 49.6% were males and 4.5% were minority nationality) were randomly sampled under multistage stratification, from 25 cities which representing 15 provinces of China. Based on the Child Neglect Norms used by China, prevalence of CN was identified and SPSS-Windows 11.0 was employed for statistical analysis. Scores, frequency/degrees, age, sex and 5 types (physical, emotional, educational, medical and safety) of CN on every group of the regions, were calculated. Multifactorial analysis was conducted through Binary Logistic Regression and multiple linear regression to determine the relevant risk factors. RESULTS: (1) The average degree of CN for the 3 - 6 year-olds was 42.2, with its prevalence as 28.0%. Degrees of CN for the groups of 3, 4, 5, 6-year-olds were 41.7, 42.2, 42.1 and 43.1 (F = 0.988, P > 0.05), with frequencies of 25.0%, 25.3%, 27.9% and 35.4% (chi(2) = 4.798, P > 0.05), respectively. Degrees for CN in males and females were 42.7 and 41.8 (F = 2.502, P > 0.05) with the frequencies as 32.6% and 23.7% (chi(2) = 6.585, P < 0.05), respectively. Degrees of CN for the five types were 39.4-43.4 with the frequencies as 5.1%-12.9%, respectively. No significant difference was found in the frequency of the types (with an exception on 'physical neglect') between males and females (P > 0.05). The highest frequency (42.9%) of CN was seen in the single-parent families and the lowest in large family with three generations (25.5%). (2) According to monofactorial chi(2) test, the possible risk factors of CN would include: educational background, occupation and decrease of income of the parents during last year, etc. (3) Binary Logistic regression analysis showed that the influential factors to the occurrence of CN would include: father's educational background, sex of the child and mother's occupation, etc. (4) Multiple linear regression showed that the influential factors to the degree of CN were: family structure, number of supporting family members, relationship between parents and children, etc. CONCLUSION: The degree and frequency of CN among children aged 3 to 6 in the urban areas of China were high but similar among the four age groups. Male children had a higher frequency of neglect than females, but with similar degree. Children in single-parent families had the highest frequency. The major influential factors of CN would include: educational background, occupation, family structure, family income of the parents which were similar to the results reported from foreign literature.

Child↗

[Infiltration length of gastric cancer on giant sections].

BACKGROUND & OBJECTIVE: The resection boundary for gastric cancer is controversial. The study was designed to investigate gastric wall infiltration length of gastric cancer. METHODS: A total of 105 patients with gastric cancer who underwent gastrectomy at Cancer Center of Sun Yat-sen University from Apr. 2002 to Feb. 2004 were eligible. During gastrectomy, gastric wall lengths of 18 patients before traction (L1), after traction (L2), and after isolation (L3) were measured. Longitudinal specimen along the center of gastric cancer was fixed to measure the lengths of proximal and distal margins to the cancer. Giant section was observed under microscope to calculate the true infiltration length in proximal and distal margins according to the principle of the length changing uniformity. RESULTS: In the 18 specimens, L2 was significantly longer than L1 and L3 (P < 0.05); no significant difference was showed between L1 and L3 (P > 0.05). The infiltration length of localized gastric cancer, including early stage cancer, Borrmann I type cancer, and Borrmann II type cancer, was less than 2 cmû that of invasive gastric cancer, including Borrmann III type cancer and Borrmann IV type cancer, was less than 5 cm. CONCLUSION: The resection length for localized gastric cancer is at least 2 cm to tumor margin, and for invasive gastric cancer is at least 5 cm to tumor margin.

Adenocarcinoma↗

[Up-regulation of costimulatory molecules by sodium butyrate in acute leukemia cells and its molecular mechanism].

OBJECTIVE: To explore the effect of sodium butyrate (SB) on the expression of costimulatory molecules in acute leukemia cells and its mechanism. METHODS: The expression of CD86 and CD80 was examined on the surfaces of NB4, HL-60, Kasumi-1, U937 and Jurkat cells by flow cytometric analysis after treated by SB or not. Allogeneic mixed lymphocyte reaction was used to evaluate the immunomodulatory effects of cells treated by SB. Activated NF-kappaB was measured with an NF-kappaB assay kit. RESULTS: Up-regulation of CD86 and CD80 at various levels was observed on these leukemia cells treated by SB. The ratio of CD86 expressing cell in NB4 cells treated by 0.5 mmol/L SB was 36.8 times higher than that in control. Up-regulation of NF-kappaB was similar to that of CD86. Allogeneic lymphocyte proliferation was strongly stimulated by the SB treated cells. CONCLUSION: SB can improve the expression of CD86 in acute leukemia cells. NF-kappaB was an important transcription factor involved in the up-regulation of CD86.

B7-1 Antigen↗

[Construction and expression of scFv phage antibody from natural anti-keratin monoclonal antibody 3B4].

AIM: To construct and express the scFv phage antibody from natural anti-keratin monoclonal antibody 3B4 in E.coli and then compare its antigenic specificity with that of the parental antibody 3B4. METHODS: The V(H) and V(L) of 3B4 were amplified by PCR from pMD-18T- mAb 3B4 V(H) and pMD-18T- mAb 3B4 V(L), and then cloned into the phagemid pscMH. E.coli was transfected by recombined pscMH and superinfected by the helper phage VCSM13. Then the antigenic specificity of the scFv concentrated from the supernatant of the transfected E.coli was detected by indirect ELISA. RESULTS: DNA sequence analysis showed that the scFv sequence was the same as the original sequence except that there was one base mutation in the FR1 of V(L). Indirect ELISA showed that the scFv phage antibody was polyreactive as mAb 3B4, but its antigenic specificity was not the same with that of mAb 3B4. CONCLUSION: The scFv phage antibody from natural anti-keratin monoclonal antibody 3B4 was successfully constructed and expressed. Its antigenic specificity was different from that of its parental antibody 3B4.

Amino Acid Sequence↗

[The relationship between the expression of HIF-1alpha and the angiogenesis in infancy hemangioma].

OBJECTIVE: To investigate the expression of HIF-1alpha and its roles on the vascular endothelial cell growth factor (VEGF) and microvessel density (MVD ) in hemangioma. METHODS: Immunohistochemical streptavidin/peroxidase(SP) stain was applied to examine the expression of HIF-1alpha, VEGF and CD34. The amount of microvessel was counted, which the endothelial cell expressed CD34. RESULTS: The nuclei and cytoplasm of the endothelial cell showed positive staining for HIF-1alpha in hemangioma. In 28 cases, positive rate for HIF-1alpha was 64%, for VEGF was 71.4%. In the proliferating phase, positive rate for HIF-1alpha was 87.5%, for VEGF was 93.7%. However, the positive rate for HIF-1alpha, in the involuting phase, was 33.3%, and for VEGF was 41.7%. There was a very significantly different between two phases (P < 0.01). In the proliferating phase, MVD was 73.4 +/- 14.63 . In the involuting phase, MVD was 30.2 +/- 9.1 (P < 0.01). The correlation between the HIF-1alpha and VEGF was positive (P < 0.01). There was a positive correlation between the HIF-1alpha and MVD (P < 0.01). CONCLUSIONS: There might be a special hypoxia microenvironment in endothelial cell of the hemangioma in proliferating phase , which could up-regulate the expression of the HIF-1alpha protein. The HIF-1alpha protein could also up-regulate the VEGF protein and then result in the angiogenesis.

Adolescent↗

[Determination of complanatoside A in semen Astragali complanati by HPLC].

OBJECTIVE: To establish the determination method for complanatoside A in seeds of Astragalus complanatus. METHOD: An HPLC method has been developed to separate complanatoside A on ZORBAX EXTEND-C18 (4.6 mm x 250 mm, 5 microm) column with acetonitrile-water-phosphoric acid (20:80:0.2) as mobile phase and UV detection at 267 nm. RESULT: The good linearity of complanatoside A ranged 0.086-0.430 microg, r = 0.9999. An average recovery of 99.8% (n = 5) was obtained with a RSD of 1.0%. CONCLUSION: The established method is proved to be stability, fast, accurate and can be used for quantification of Complanatoside A in Semen Astragali Complanati.

Astragalus Plant↗

[Relationship between congenital long QT syndrome and Brugada syndrome gene mutation].

OBJECTIVE: To investigate the molecular pathology in families with long QT syndrome (LQTS) including Jervell-Longe-Nielsen syndrome (JLNS) and Romano-ward syndrome (RWS) and Brugada syndrome (BS) in Chinese population. METHODS: Polymerase chain reaction and DNA sequencing were used to screen for KCNQ1, KCNH2, KCNE1, and SCN5A mutation. RESULTS: We identified a novel mutation N1774S in the SCN5A gene of the BS family, a novel mutation G314S in a RWS family which had also been found in Europe, North America, and Japan, and a single nucleotide polymorphisms (SNPs) G643S in the KCNQ1 of the JLNS family. In this JLNS family, another heterozygous novel mutation in exon 2a was found in KCNQ1 of the patients. CONCLUSION: New mutations were found in our experiment, which expand the spectrum of KCNQ1 and SCN5A mutations that cause LQTS and BS.

Adolescent↗

[Effects of Qilan Tangzhining capsule on glucose and lipid metabolism in rats with diabetes mellitus and hyperlipemia].

OBJECTIVE: To study the effects of Qilan Tangzhining capsule on glucose and lipid metabolism in diabetes mellitus and hyperlipemia. METHOD: Rats were fed with high sugar and fat food for 2 months, then 2% streptozocin (STZ, 30 mg kg(-1)) was injected intraperitoneally to induce hyperglycemia and hyperlipemia. After the model rats were administrated drugs, the blood glucose, the serum lipids, and the histopathology of the liver and pancreas were observed. RESULT: Qilan Tangzhining capsule could decrease the FBG and the serum TC, TG, LDL-C, increase HDL-C, and improve the histopathologic injury of the liver and pancreas. CONCLUSION: Qilan Tangzhining capsule can not only adjust the blood glucose and lipid, but also improve the histopathology injury of the liver and pancreas.

Animals↗

[Effects of Guanyu capsule on the behavior and cerebral cortex monoamine neurotransmitters in depressive model of olfactory bulb damage rats].

OBJECTIVE: To investigate the behavioral changes and the levels of monoamine neurotransmitters in the anterior cortex in the olfactory bulb damage rats after being treated with Guanyu capsules (GYC). METHOD: Open-field test and step-down passive avoidance test were used to observe the behavior in model rats. HPLC-ECD was used to analyze the influences of GYC on the levels of monoamine neurotransmitters. RESULT: In the model rats, there was a characteristic hyperactivity in the Open-field and learning deficits in step-down passive avoidance (P < 0.01). The contents of 5-HT reduced, and the rate of DOPAC/DA increased significantly (P < 0.01). GYC 1.2, 0.6 g x kg(-1) could correct behavioral changes increase the contents of 5-HT, and decrease DOPAC/DA level (P < 0.01). CONCLUSION: GYC can correct behavioral changes in rats model of olfactory bulb damage, and regulating 5-HT and DA metabolism in cortex is one of the antidepressive mechanisms of GYC.

3,4-Dihydroxyphenylacetic Acid↗

Regular expression of discoidin domain receptor 2 in the improved adjuvant-induced animal model for rheumatoid arthritis.

OBJECTIVE: To investigate the expression of discoidin domain receptor 2 (DDR2) of fibroblast-like synovial cells in improved adjuvant-induced animal (AIA) model for rheumatoid arthritis (RA) and to provide evidence for DDR2's antagonist use clinically. METHODS: AIA was modified by administrating 0.1 mL of complete Freund's adjuvant (CFA, mixed with 5 mg Bacillus Calmette-Guerin vaccine/mL) into rats' right hind paws and 0.125 mL tumor necrosis factor-alpha (2 U/mL) into right ankles and subpatellar fatty tissue. The expression of DDR2 in fibroblast-like synovial cells was assessed using immunohistochemistry, immunofluorescence histochemistry, and in situ hybridization methods. Levels of anti-collagen II antibody were measured using enzyme-linked immunosorbent assay. RESULTS: Given the terms mentioned above, we found a more practical rat model, apparently decreasing immunization time (average 3-5 days). DDR2 can be detected upon the 15th day of immunization; expression gradually increased with time going on, and reaching a peak 35 days after immunization before gradually decreasing. Serum anti-collagen II antibody showed similar expression patterns as DDR2, but reached peak later than DDR2, about 40 days after immunization. CONCLUSION: Regular expression of DDR2 in animal models infers its important role in the pathological process of RA.

Animals↗

[Dynamic release of tinidazole from the degradable PLLA-tinidazole blend gel].

OBJECTIVE: To determine the dynamic release of tinidazole from the degradable poly-lactic acid (PLLA)-tinidazole blend gel (a periodontal local drug delivery) by high-performance liquid chromatography (HPLC) in vitro and to observe the polylactic acid (as a vector of tinidazole) how to affect the release of tinidazole. METHODS: HPLC analysis was conducted. The operating conditions were C18-ODS-A column, water-methanol-acetic acid as mobile phase at a flow rate of 1.5 ml/min and a detection wavelength at 310 nm and a column temperature at 30 degrees C. RESULTS: The retention time of tinidazole was about 12 min. There was good linear relationship between the concentrations of tinidazole in blend gel and their peak areas in the ranges of 5 - 500 mg/L. The regression reaction was y = 0.836 + 8.452 2 x 10(-5) x (r = 0.998 6). RSD was 0.2%. Polylactic acid had no influence on the determination of tinidazole. The daily average release of tinidazole was 5.60%. The cumulative release of tinidazole was about 78.40% in 14 days. CONCLUSION: The in vitro drug release analysis is an useful method in evaluating the performance of local drug delivery system. HPLC analysis is a simple and accurate method with good reproducibility.

Chromatography, High Pressure Liquid↗

[Beneficial neurohormonal profiles of beta-blockades in chronic left heart failure].

OBJECTIVES: The aims of this study were to evaluate the effects of beta-blockers on neurohormonal factors in patients with chronic left heart failure (CHF). METHODS: 44 patients, 33 men and 11 women, with age of 60.1 +/- 10.6 years with chronic left heart failure (ejection fraction less or equal to 40% by UCG) were included in this study. All patients received conventional therapy and were randomly assigned either to a bisoprolol or carvedilol group. The dosage of beta-blockers were increased gradually to target or the tolerant dosages (bisoprolol 10 mg qd, carvedilol 25 mg bid) during 3 months in 36 patients. Maintenance dose was continued for 4 months. Plasma concentrations of renin activity (PRA), angiotensin II (Ang II), aldosterone (Ald) and the N-terminal portion of brain natriuretic (NT-proBNP) were assessed with RIA and ELISA at baseline and 3 and 7 months after staring beta-blocker therapy. Left ventricular ejection fraction (LVEF, Modify SIMPSON) was assessed at baseline and 7 months after starting therapy. RESULTS: (1) In patients with left heart failure, the baseline plasma level of PRA, Ang II and Ald were at normal range. N-terminal BNP concentration was much higher than 200 pg/ml as a result of impaired systolic function, as it elevated with increasing of NYHA grade. (2) The plasma level of NT-proBNP decreased significantly, as compared with that before therapy, but there is no significant change of plasma level of PRA, Ang II and Ald. (3) There were no significant differences between the event group and non-event group for the plasma level of renin-angiotensin and aldosterone during 7 months after starting beta-blocker. The Plasma levels of NT-proBNP were much higher in the event group than non-event group. (4) Multi regression analysis showed that the value of LVEF increased with the decreasing of NT-proBNP levels (beta = -0.389, P = 0.009) and increasing of Ang II level (beta = 0.341, P = 0.020) at baseline. After-therapy LVEF increased with the decreasing of NT-proBNP levels at titration-end (beta = -0.424, P = 0.020). CONCLUSIONS: The plasma level of NT-proBNP is more sensitive and accurate than the plasma level of PRA, Ang II and Ald in evaluation of severity and prognosis of CHF. beta-Blocker administration in patients with CHF decreases circulating levels of NT-proBNP and thus improves left ventricular function, but there is no significant effect on plasma level of PRA, Ang II and Ald.

Adolescent↗

[Efficacy of gefitinib on Chinese patients with locally advanced or metastatic non-small cell lung cancer: a clinical trial].

BACKGROUND & OBJECTIVE: Gefitinib, a selective inhibitor of epidermal growth factor receptor (EGFR) tyrosine kinase, has been approved to be used in treatment of locally advanced or metastatic non-small cell lung cancer (NSCLC) in many countries. This study, a multicenter clinical trial, was designed to evaluate the efficacy of gefitinib on Chinese patients with locally advanced or metastatic NSCLC after failure of previous chemotherapy, and explore its safety. METHODS: A total of 159 pathologically-confirmed NSCLC patients were enrolled. Gefitinib was orally administered 250 mg once daily until disease progression or the occurrence of intolerable toxicity. RESULTS: The objective response rate was 27.0%; the disease control rate was 54.1%. The median progression-free survival time was 97 days; the median overall survival time was 10.0 months; the 1-year survival rate was 44%. The most common drug-related adverse events were rash (44.0%), pruritus (15.7%), and diarrhea (10.1%), and most of them were grade 1-2 events with no need of further treatment. CONCLUSION: Gefitinib is effective and safe in treating Chinese patients with locally advanced or metastatic NSCLC after failure of previous chemotherapy.

Adult↗

[Reactivity of IgG class of anti-keratin autoantibodies in healthy human sera].

AIM: To analyze the reaction patterns of IgG class of anti-keratin autoantibodies (AK auto Abs) in normal human sera before and after purification, and to explore the effects of serum non-IgG components on the reaction patterns of IgG class of AK auto Abs. METHODS: Titers of IgG AK auto Abs in healthy human sera before and after purification were measured by indirect ELISA, and the reaction patterns of the AK auto Abs to a group of keratins with different relative molecule mass were analysed by Western blot. RESULTS: Titers of purified IgG class of AK auto Abs were higher than those of unpurified sera. Western blot analysis showed purified AK auto Abs recognized more keratins with stronger avidity than unpurified AK auto Abs. The reaction patterns of AK auto Abs from different individuals tended to be homogenous after purification. CONCLUSION: The reaction patterns of serum IgG class of AK auto Abs are influenced by some non-IgG components in sera. The homogeneity of reaction patterns of AK auto Abs from different individuals indicated that B cells producing IgG class of AK auto Abs may be selected by a set of conserved self-antigens, and this process may have no relationship with an individual's exposure to foreign antigens.

Adult↗

[Studies on subset, location and secretion of natural keratin-reactive B cells].

AIM: To clarify the subsets and location of B cells responsible for the production of natural anti-keratin autoantibody (AK auto Ab), and analyze the function of each subset. METHODS: Cells isolated from spleen and peritoneal cavity of C57BL/6 mice were cultured in vitro. FACS was employed to detect keratin reactive B cell subsets. The anti-keratin IgM level in supernatant was analyzed by ELISA, while ELISPOT was utilized to detect the B cells which can secrete AK auto Ab. RESULTS: Keratin reactive B cells were mainly marginal zone B cells in spleen, while they were mainly B-1a cells in peritoneal cavity. There were more B cells producing AK auto Ab in peritoneal cavity than in spleen. The anti-keratin IgM level in the supernatant of cultured peritoneal cells was much higher than that of splenocytes. CONCLUSION: There are three subsets of keratin-reactive B cells: B-1 B cells, follicular B cells and marginal zone B cells. B-1 B cells are active in secreting AK auto Ab.

Animals↗

[Antisense hypoxia inducible factor-1alpha and B7-1 combination gene therapy for mouse lymphoma].

OBJECTIVE: To investigate the synergistic effects of antisense HIF-1alpha gene therapy combined with B7-1-mediated immunotherapy on cancer treatment. METHODS: Antisense HIF-1alpha and B7-1 expression vector were constructed. Lymphoma cells EL-4 were injected subcutaneously into C57BL/6 mice and transplanted lymphomas were established. The mice received either antisense HIF-1alpha, B7-1, or a combinational agent, complexed with DOTAP cationic liposomes. The tumor growth in the mice was monitored. Expression of HIF-1alpha, B7-1 and VEGF were detected by immunohistochemistry and Western blotting. The tumor blood vessels were immunostained with CD31- antibodies and the tumor vascular density was assessed by light microscopy. RESULTS: Gene transfer of plasmid expressing the encoded antisense HIF-1alpha inhibited VEGF expression and reduced vascular density in the tumors, eradicated tumors in diameter smaller than 0.1 cm and only retarded the growth of larger tumors. Whereas combination of antisense HIF-1alpha gene therapy and B7-1 immunotherapy eradicated all tumors in diameter of 0.4 cm. CONCLUSION: Antisense HIF-1alpha blocks tumor hypoxia pathway by downregulating VEGF expression, reduction of vascular density and enhances B7-1-mediated immunotherapy. Strategies that target HIF-1 may have therapeutic potential in cancer treatment and are worthy of further studying.

Animals↗

[The effect of Doppler effect on ultraviolet absorption spectrum from difference in temperature (UVASDT)].

In this paper, the formation of UV absorption spectrum from difference in temperature (UVASDT) is discussed. Broadening of spectral lines might be one of the reasons for the formation of UVASDT. The effect of temperature on the broadening of spectral lines is analyzed. The Doppler SDT function is deduced, and the SDT of C60 and progesterone can be explained by it. It is indicated that the Doppler effect might be the primary reason for the formation of UVASDT of this kind of substance.

Algorithms↗