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Biomedical subjects

Jian-jun Li

Publications and source records attributed to Jian-jun Li.

32 records · Page 2Linked to original sources

[Effects of components isolated from Astragalus mongholicus on expression of p-selectin in shock wave induced kidney injury in rabbit model].

OBJECTIVE: To investigate the effective components of Astragalus mongholicus and their mechanisms in alleviating extracorporeal shock wave lithotripsy (ESWL) induced kidney injury. METHOD: 69 male rabbits were randomly assigned into control group, sham treatment group, Total Saponins of Astragalus (TSA) group, Total Flavonoids of Astragalus (TFA) group, and Total Polysaccharide of Astragalus group (TPA). The shock wave treated kidneys were observed for the expression of p-selectin and the change of cells ultrastructure pre and post ESWL. The concentration of Maleic Dialdehyde (MDA) as well as activity of superoxide dismutase (SOD) in the kidney tissues was also analyzed. RESULT: After application of shock wave treatment, p-selectin was expressed extensively in renal glomerulus, renal tubules and renal interstitium of the treated kidneys. It showed a significant increase of MDA levels and decrease of SOD activity in control group (P < 0.05) after ESWL. The comparison between controls and TSA group demonstrated that TSA could significantly reduce the positive rate of p-selectin P < 0.05) and alleviate the injuries of cells ultrastructure. The results also showed a significant decrease of MDA levels and increase of SOD activity in TSA group compared to controls (P < 0.05). The protective effects of TFA and TPA in alleviating kidney injury induced by shock wave were lower than those of TSA; they had no effects of the expression of P-selectin. CONCLUSION: TSA is the main components of A. mongholicus in alleviating shock wave induced kidney injury not only by scavenging oxygen free radicals but also inhibiting the expression of p-selectin.

Animals↗

Automatically extracting sheet-metal features from solid model.

With the development of modern industry, sheet-metal parts in mass production have been widely applied in mechanical, communication, electronics, and light industries in recent decades; but the advances in sheet-metal part design and manufacturing remain too slow compared with the increasing importance of sheet-metal parts in modern industry. This paper proposes a method for automatically extracting features from an arbitrary solid model of sheet-metal parts; whose characteristics are used for classification and graph-based representation of the sheet-metal features to extract the features embodied in a sheet-metal part. The extracting feature process can be divided for valid checking of the model geometry, feature matching, and feature relationship. Since the extracted features include abundant geometry and engineering information, they will be effective for downstream application such as feature rebuilding and stamping process planning.

Algorithms↗

[Effects of recombined pcDNA3.1-hBMP-2 transfection on human marrow stromal stem cells proliferation and vascular endothelial growth factor expression].

OBJECTIVE: To construct the recombined DNA pcDNA3.1-hBMP-2 and transfect into human marrow stromal stem cells (MSCs) in vitro, and to explore the effects of transfection on cellular proliferation and expression of vascular endothelial growth factor (VEGF). METHODS: The expression of human bone morphogenetic protein 2(hBMP-2) in these cells after transfection was determined by in situ hybridization and immunohistochemical analysis and Western blot analysis. The changes of cell proliferation were observed by flow cytometry. The effects of BMP-2 gene transfection on expression of VEGF in the cells were analyzed by in situ hybridization of VEGF cDNA probe. RESULTS: Stable expression of hBMP-2 in pcDNA3.1-hBMP-2 transfected MSCs was confirmed in the levels of mRNA and protein. Cellular proportion in S period increased, which indicated that the synthesis of cell DNA increased. The expression of VEGF in the cells increased obviously. CONCLUSION: With the help of lipofectamine, the pcDNA3.1-hBMP-2 were transfected into human MSCs successfully. hBMP-2 plays an important role in promoting cellular proliferation and vascular generation during bone repair.

Bone Marrow Cells↗

Effect of angiotensin II receptor 1 antisense oligodoexynucleotides on physiological and pathophysiological growth of cardiomyocytes.

AIM: To evaluate the role of angiotensin II receptor 1 antisense oligodexynucleotides (AT1R-AS-ODNs) on physiological and pathophysiological growth of cardiomyocytes from normotensive rats. METHODS: Cardiomyocytes were transfected with AT1R-AS-ODNs (200 nmol/L) followed by treatment with or without angiotensin II (1 micromol/L). In situ hybridization and Western blot were used for AT1R mRNA and protein detection, respectively. c-Jun N-terminal protein kinase (JNK) activity was characterized by immune complex kinase assay. c-Jun protein expression was examined by immunocytochemistry. DNA content was detected by flow cytometric assay. Atrial natriuretic factor (ANF) expression was identified by radioimmunoassay. RESULTS: Treatment with AT1R-AS-ODNs for 24 h resulted in 51.2 % decrease in AT1R mRNA and 60.7 % in protein (P<0.05 vs control). However, the basal level of JNK activity, c-Jun protein expression, and DNA content were not altered by AT1R-AS treatment in absence of overactive hormonal system. After treatment with angiotensin II for 30 min, both p46JNK and p54JNK were robustly activated. By 2 h, c-Jun protein expression was increased. By 24 h, angiotensin II caused a marked increase both in G0/G1 and G2/M DNA content, and increased ANF expression by 1.8-fold. All these were inhibited by AT1R-AS-ODNs pretreatment. In contrast, sense sequence was ineffective. CONCLUSION: Decrease of AT1R expression by AS-ODNs did not interfere with normal growth, but protected cardiomyocytes from angiotensin II-dependent pathophysiological growth.

Angiotensin II↗

[Comparison of serum biochemistry between specific pathogen-free and conventional aged Wistar rats].

OBJECTIVE: To investigate the differences in serum biochemistry between specific pathogen-free (SPF) and conventional aged Wistar rats. METHODS: Coulter-JT Analyzer was used to measure the values of serum biochemistry in the two grades of rats. RESULTS: The serum levels of alanine aminotransferase (ALT), total protein (TP), alkaline phosphatase (ALP), total cholesterol (TC), triglyceride (TG), blood urea nitrogen (BUN), creatinine, Fe, P, glucose, uric acid (UA), and low density lipoprotein (LDL) were very significantly different between male and female Wistar rats of either conventional or SPF grade (P<0.01), which also had significant difference in albumin, lactate dehydrogenase (LDH) and apolipoprotein B (ApoB) (P<0.05). Between male aged Wistar rats of the two grades, the differences of TP, albumin, albumin/globulin (A/G) ratio, TC, TG, blood glucose, ApoA1, ApoB, UA, high-density lipoprotein (HDL), LDL, and glutamic oxalacetic transaminase (GOT) were very significant (P<0.01), with also significant differences in ALT, Fe, Mg (P<0.05). Between the female rats of the two grades, the serum levels of ALT, TP, albumin, A/G ratio, ALP, TG, BUN, creatinine, Fe, ApoA1, APOB, HDL, LDL, and bile acids were very significantly different (P<0.01), and Mg was significantly different (P<0.05). CONCLUSION: Different microbiological profiles affect serum biochemistry of aged Wistar rats.

Aging↗

[Prevalence of low vision and blindness in defined populations in rural and urban areas in Beijing].

OBJECTIVE: To investigate the prevalence and causes of low vision and blindness in Beijing residents aged 40 and over. METHODS: 4,451 residents aged 40 and over in 3 rural communities and 5 urban communities in Beijing underwent eye examination, including examination of distant and near visual acuity (VA), best corrected distant and near VA, pinhole VA, and visual field, slit lamp biomicroscopy, and dilated ocular examination in the form of in-home survey by defined population-based sampling. The medical history was surveyed too. The data were analyzed based on the criteria of the World Health Organization. RESULTS: The general prevalence rates of low vision and blindness were 0.99% (95% CI: 0.70-1.28) and 0.39% (95% CI: 0.21-0.57) respectively. The prevalence rate of low vision in females was 1.45%, 2.23 times that of males (0.65%) (OR: 1.97, 95% CI: 1.00-3.95). The prevalence rate of low vision of rural residents was 1.76%, 2.89 times that of urban residents (0.61%) (OR: 2.93, 95% CI: 1.43-6.11). The prevalence rate of blindness in females was 0.64% and 0.37% in males. The prevalence rate of blindness of rural residents was 1.06%, 2.04 times that of the urban residents (0.52%) (OR: 3.77, 95% CI: 1.41-10.62). The 3 major causes of blindness were cataract (37.50%), glaucoma (29.20%), and high myopic macular degeneration (8.30%). The prevalence of blindness increased with age. CONCLUSION: The prevalence rates of low vision and blindness are higher in the rural areas. Cataract, glaucoma, and high myopic macular degeneration are the major causes of blindness. The prevalence of low vision and blindness are influenced by age, sex; area, health care level, educational level, and environmental factors.

Adult↗

[High intensity focused ultrasound for liver cancer].

OBJECTIVE: To evaluate the effect of high intensity focused ultrasound (HIFU) for liver cancer. METHODS: HIFU treatment was performed in 44 liver cancer patients under general anesthesia and ultrasound positioning. Before and after HIFU treatment, the clinical symptoms, liver functional tests, AFP and MRI were evaluated. RESULTS: After HIFU treatment, the remission rate of clinical symptoms was 87.5% (28/32), with the scanty ascites in 3 patients disappeared. ALT (79.73 +/- 12.31 U/L) and AST (103.47 +/- 24.55 U/L) before HIFU were reduced to normal in 84.6% (22/26) and 73.5% (25/34) patients. AFP in 64.3% (18/28) patients decreased > or = 50% of the original value. After HIFU, MRI showed coagulative necrosis and blood supply reduction or disappearance of tumor in the target region. CONCLUSION: HIFU treatment pocesses good effect on liver cancer, which will offer a considerable weight in noninvasive local treatment of hepatic tumor.

Adult↗

[The application of digital photography with retroillumination for lens in cataract study].

OBJECTIVE: To evaluate the reliability of digital photography with retroillumination for lens as a tool to assess the degree of lens opacity, and to study the morphological features of some lens diseases using the digital images. METHODS: The cataract screener (Neitz CT-S) was connected to a computer capable of acquiring digital images of lens. The digital lens retroillumination and slit lamp images were collected in 64 eyes. Three independent separate examiners took three sets of different CT-S digital photographs in four cataract subjects. The area of lens opacification in the images was measured and analyzed using threshold adjustment in PhotoShop software and a customized program in Matlab software. RESULTS: The distinct digital images of lens cortical opacity, posterior subcapsular opacity and other lens diseases were obtained with CT-S computer digital photography, which images were much better than slit lamp sectional digital images. The sensitivity and specificity of measuring lens opacification with CT-S digital images were 90% and 94% respectively. However, the digital lens retroillumination images were not as sensitive as the slit lamp images for nuclear cataracts. The variation coefficients of lens opacity area in the three sets of CT-S digital images in the same subject, which were taken by the independent examiners, were from 2.23% to 10.86%. The cortical opacification in CT-S digital images was linear, cuniform or clustered aggregate shadow configuration. The posterior subcapsular opacification was discal vacuolar or granular appearance. CONCLUSIONS: The reproducibility of the CT-S digital images taken by the independent examiners is excellent. This technique can objectively show cortical or posterior subcapsular opacities, but nuclear cataracts.

Adult↗

[Determination of trace lead in huaiyao by separating and enriching with sulfhydryl cotton-flame atomic absorption spectrometry].

The determination of trace lead in Huaiyao after separating and enriching with sulfhydryl cotton by FAAS is described in this paper. The enriching and eluting conditions were studied. The recovery of lead is 97.0%-102.0%. RSD is less than 4.3% sulfhydryl cotton is effective in eliminating the interference for common existing elements. The characteristics of this method is fast, simple and convenient. The determine results were consistent.

Drug Contamination↗

[A study of the architectural factors and the infection rates of healthcare workers in isolation units for severe acute respiratory syndrome].

OBJECTIVE: To investigate measures to prevent the outbreak of severe acute respiratory syndrome (SARS) in healthcare workers in isolation units. METHODS: The architectural factors and the infection of healthcare workers in different wards in our hospital between 30 January 2003 and 30 March 2003 were analyzed. RESULTS: Four kinds of isolation wards were evaluated, including the ward where the thirty-first bed lied in on the twelfth floor, the laminar flow ward in the intensive care unit (ICU) where the tenth bed lied in on the fifteenth floor, the ward where the twenty-seventh bed lied in on the thirteenth floor of Building A, and thirty wards on the fourteenth to eighteenth floors of Building B. The ratios (m2/m3) of the area of the ventilation windows to the volume of the room were 0, 0, 1:95 and 1:40, respectively. Numbers of SARS cases in the wards mentioned above were 1, 1, 1 and 96, respectively. The total lengths (hour) of hospitalization were 43, 168, 110 and 1,272, respectively. The infection rates of the healthcare workers in the areas mentioned above were 73%, 32%, 28% and 2%, respectively. The difference of the infection rates was of statistical significance. CONCLUSION: In addition to strict personal protective measures, isolation of SARS cases in wards with high ratio of the area of ventilation windows to the volume of the room and good ventilation may be the key to preventing the outbreak of SARS in healthcare workers in isolation units.

Adult↗

[Determination of Cu, Zn and Fe in Huaiyao by suspension sampling-flame atomic absorption spectrometry].

A new method--suspension sampling technique was applied to flame atomic absorption spectrometry and was successfully used to determine Cu, Zn, Fe in Huaiyao. Then studied the choice of suspension agent and elimination of chemical interference. The huaiyao sample was suspended in agar sol, and injected into air-acetylene flame by using standard addition method to determine Cu, Zn, Fe. Determined results were consistent with those obtained by HNO3 + H2SO4 + HClO4 method. The t-test showed that no obvious difference was found between the two methods. Displacement of HNO3 + H2SO4 + HClO4 method by suspension sampling method for the sample pretreatment is possible. This method is convenient, rapid and accurate.

Copper↗

[Determination of trace sulfur and mercury in the Chinese traditional medicine].

This paper reports that the sulfur compounds of traditional Chinese medicine were reduced to S2- by Auger reagent, and determined by cold atomic fluorescence. At the same time the trace mercury was determined. The conditions the for quantitative determination of Hg2+ and S2- were obtained. The linear range of the determination is 11.20-55.60 mg.mL-1, the correlation coefficient is 0.999 78. In this method, little reagent is needed, the treatment of the sample is simple, the process of determination is convenient, and the sensitivity is high.

Astragalus Plant↗