Biomedical subjects

Z Shen

Publications and source records attributed to Z Shen.

At least 55 records · Page 3Linked to original sources

PubMed2001

[The prevalence of renal artery stenosis in patients with coronary artery disease].

OBJECTIVE: To understand the prevalence of renal artery stenosis(RAS) in patients with coronary artery disease(CAD) and the relations among coronary artery disease, renal artery stenosis, hypertension and renal insufficiency. METHODS: 280 patients with coronary artery disease or suspected coronary disease were carried out renal artery angiography after coronary angiography over 1 year period. RESULTS: Of the total patient cohort, 43(15.3%) had significant RAS (> or = 50%), 3(1.0%) were obstructed and 14 (5.0%) were bilateral. 36 (19.1%) were diagnosed as having significant RAS among 188 CAD patients. 7 patients with significant RAS were found among 92 patients without significant coronary artery stenosis, all of them were found in the group of 22 patients with mild coronary artery atheroscloresis. The prevalence of significant RAS was 19.6% and 7.9% as referred to with or without hypertension, P < 0.05. 10 patients (55.6%) had significant RAS in 18 patients with mild renal insufficiency as compared to 33 patients (12.6%) had significant RAS in 262 patients with normal renal function, P < 0.05. In the subgroup of CAD, the prevalence of significant RAS were 15.3%, 17.1%, 25.4% in single vessel disease, two vessel disease and triple vessel disease patients, P < 0.05. 35 patients (81.4%) had hypertension among these 43 patients with RAS with 24 (56.0%) patient's blood pressure difficult to control. CONCLUSIONS: RAS is a frequent finding in patients with CAD, especially in triple vessel disease patients. Hypertension is closely related to RAS, it should be the risk factor of RAS, and can be the clinical manifestation of RAS. CAD patients with renal insufficiency but without history of chronic glomerulonephritis may indicate RAS.

Adult↗

PubMed2001

[Effect of rice canopy structural changes on bidirectional reflectance].

The study of vegetation bidirectional reflectance is useful for remote sensing data interpretation. Vegetation canopies information such as leaf area index, mean leaf inclination, mean plant height, and coverage, can be inverted from vegetation bidirectional reflectance. This paper discussed the dynamics of vegetation canopies reflectance with vegetation canopy structures by measuring rice canopy structure and bidirectional reflectance at 26, 35, 41, 49, 62, 67 and 86 days after transplanting. It is concluded that the sensitivity of vegetation canopies to directional reflectance variations varied with canopy structures, and hence, through bidirectional reflectance, more information about canopy structure can be know.

Light↗

PubMed2001

Investigation of infection risk and the value of urine endotoxin during extracorporeal shock wave lithotripsy.

OBJECTIVE: To clarify the infection risks and the value of endotoxin determination in urine during extracorporeal shock wave lithotripsy (ESWL). METHODS: According to the distribution and complications of upper urinary calculi, 164 patients were divided into five groups. Group A consisted of 48 patients with 1 to 4 renal calculi, which were or less than 2 cm in diameter. Group B was composed of 24 patients with renal calculus larger than 2 cm in diameter or one to multiple renal calculi. Group C was composed of 22 patients with 1 to 3 renal calculi accompanied by 1 to 2 ureteric calculi. Group D consisted of 51 patients with 1 to 3 ureteric calculi that were 0.5 to 1.2 cm in diameter, respectively. Group E included 19 patients with complicated renal calculus, such as casting and staghorn renal calculus. Urine and blood samples of these patients were obtained before and after ESWL, respectively. Their urine samples were proven sterile prior to treatment. All samples were cultured for bacteria and investigated for endotoxin concentration by the limulus lysate test. RESULTS: No significant difference in serum endotoxin was noted before and after ESWL. Blood bacterial cultures were all negative in all patients after ESWL, similar to those before ESWL. Significant increases in urine endotoxin after ESWL compared with that before ESWL in patients of Groups B, C and E were observed, respectively (P < 0.05). There was no significant difference in urine endotoxin after ESWL compared with that before ESWL in patients of Groups A and D. The positive incidences of urine bacterial culture were significantly increased (P < 0.05) in Groups B and C and very significantly increased (P < 0.01) in Group E compared with those in Groups A and D. CONCLUSIONS: Urinary infection risk following ESWL was lower in patients with one to several renal calculi, which were less than 2 cm in diameter and did not interfere obviously with the urine flow or in patients with 1 to 3 ureteric calculi that were 0.5 to 1.2 cm in diameter. The risk was higher in those with complicated calculi, such as casting, staghorn renal calculus, renal calculus larger than 2 cm in diameter or renal calculi accompanied by ureteric calculi. For patients with higher infection risk after ESWL, prophylactic antibiotics are necessary even if bacteriuria is not present before ESWL. Endotoxin determination in urine is a reliable, sensitive and simple method for the diagnosis of bacterial infection in patients undergoing ESWL.

Adolescent↗

PubMed2001

[Study on association of vascular endothelial growth factor with the pathogenesis of pregnancy induced hypertension].

OBJECTIVE: To investigate relationship between the vascular endothelial growth factor (VEGF) and the pathogenesis of pregnancy induced hypertension syndrome (PIHs). METHODS: Twenty-three women with PIHs and twenty normal pregnant women were studied. The levels of VEGF in maternal and umbilical venous serum, placenta and decidual tissue from normal pregnancy and PIHs women were detected by enzyme linked immunosorbent assay (ELISA) and immunohistochemistry. Furthermore, the expression of VEGF mRNA in placenta and decidua was examined by reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: (1) The levels of VEGF in maternal blood were significantly lower in PIHs women than that in normal pregnancies women (10.4 +/- 3.8) ng/L and (17.0 +/- 9.3) ng/L (P < 0.01). (2) The average gray of VEGF was determined on sections of placenta and decidua from PIHs or pregnancies women by computer image analysis. The expression of VEGF in placenta and decidua (69.0 +/- 8.9) and (55.0 +/- 7.3) was decreased significantly in PIHs women than that in normal pregnancies women (75.0 +/- 9.0) and (60.5 +/- 6.4, P < 0.05). (3) The transcription levels of the VEGF mRNA in placenta and decidua were increased significantly in PIHs women than those in normal pregnancies women (4.6 +/- 3.2 vs 2.8 +/- 1.0; 6.3 +/- 2.9 vs 3.9 +/- 1.5, P < 0.01). CONCLUSIONS: These findings suggested that the abnormal expression of VEGF in PIHs occurred within the low-stream of genic transcription. It was considered that the abnormal expression of VEGF may play an important role in the pathogenesis of placental ischemia in PIHs.

Endothelial Growth Factors↗

PubMed2001

[A study of tissue factor expression and hemostatic molecular markers in patients with acute promyelocytic leukemia].

OBJECTIVES: To study the changes of tissue factor expression and hemostatic molecular markers in acute promyelocytic leukemia during all-trans retinoic acid (ATRA) or arsenic trioxide (AS(2)O(3)) treatment. METHODS: The plasma level of tissue factor (TF), tissue factor pathway inhibitor(TFPI), thrombin antithrombin complex(TAT), plasmin antiplasmin complex(PAP), urokinase type plasminogen activator(u-PA), urokinase type plasminogen activator receptor(u-PAR) and the TF level of bone marrow blasts lysate were measured by ELISA. Transcription of TF mRNA was detected by RT-PCR. RESULTS: The plasma levels of TF [(98.3 +/- 19.8) ng/L, (89.6 +/- 15.2) ng/L], TFPI [(94.4 +/- 37.0) mg/L, (93.5 +/- 36.4) mg/L], TAT [(21.9 +/- 9.6) microg/L, (18.2 +/- 9.7) microg/L[, PAP [(0.73 +/- 0.26) mg/L, (0.63 +/- 0.33) mg/L], u-PA [(0.63 +/- 0.23) microg/L, (0.57 +/- 0.01) microg/L] and u-PAR [(0.41 +/- 0.14) microg/L, (0.47 +/- 0.16) microg/L], the TF of bone marrow blasts lysate [(680.24 +/- 456.61) pg/10(7), (368.02 +/- 151.2) pg/10(7)] and transcription of mRNA were all remarkably elevated at the time of diagnosis. They all decreased after ATRA and AS(2)O(3) administration. CONCLUSIONS: There is over expression of TF, activation of coagulation system and hyperfibrinolysis, in patients with acute promyelocytic leukemia, these can be ameliorated with clinical improvement. All-trans retinoic acid and arsenic trioxide down-regulate the expression of TF mRNA and decrease the TF contents in APL blasts. However, there is also high plasma level of TF and TAT indicating the existence of hypercoagulability after remission.

Adult↗

PubMed2001

[The mechanism of percutaneous transluminal balloon angioplasty as assessed by intracoronary ultrasound].

OBJECTIVE: To elucidate the mechanism of coronary balloon angioplasty intracoronary ultrasound imaging. METHOD: Intracoronary ultrasound imaging was performed in 68 coronary arteries of 52 patients. Ultrasound images obtained at the treatment site before and after balloon angioplasty were analyzed quantitatively for cross-sectional lumen area, area enclosed by internal elastic lamina (IELA) and plaque area. Qualitative analysis included assessment of presence of dissection, plaque composition and plaque topography. RESULTS: The internal elastic lamina area was significantly enlarged after balloon angioplasty [(6.67 +/- 1.45) mm(2) vs (8.14 +/- 1.13) mm(2), P < 0.05]. The difference between IELA before and after balloon angioplasty DeltaIELA was different among different plaques (fatty plaque 1.84 mm(2), fibrous plaque 1.52 mm(2), calcified plaque 0.40 mm(2), mixed plaque 1.23 mm(2)). 85% of the lesions had dissection in some degree after PTCA. Severe dissections occurred mostly in calcified lesions. CONCLUSION: The improvement in lumen dimensions after coronary balloon angioplasty is a result of both vessel stretch, as demonstrated by a larger internal elastic lamina area at the treated site, and dissection. Calcified lesions will have less vessel stretch and severer dissection after balloon angioplasty.

Adult↗

PubMed2001

[Experimental research of laser-induced collaterals in retinal vein occlusion].

OBJECTIVE: To evaluate the feasibility and safety of establishing chorioretinal venous anastomosis in rabbit eyes with a model of branch retinal vein occlusion METHODS: By using laser photocoagulation, a chorioretinal venous anastomosis was created in rabbit eyes in which a branch retinal vein occlusion had previously been established photochemically. A similar attempt to create an anastomosis was made in the control eyes in which no branch vein occlusion was present. RESULTS: In the 21 eyes with the model of branch retinal vein occlusion, a chorioretinal venous anastomosis formed in 4 eyes within 3 to 5 weeks. In the control eyes, an anastomosis in one eye presented by 5 weeks, during follow-up of 2 to 5 months. The hemorrhage in choroid, retina and vitreous associated with laser photocoagulation were absorbed within 3 weeks, and no other severe complications were found. CONCLUSIONS: Chorioretinal venous anastomosis can be created by using laser photocoagulation. This technique is relatively safe. However, to improve the rate of successfully creating an anastomosis, more research work needs to be performed.

Anastomosis, Surgical↗

PubMed2001

[The effects of sodium butyrate on proliferation, differentiation and apoptosis in immortalized esophageal epithelial cells].

OBJECTIVE: To study the effects of sodium butyrate on proliferation, differentiation and apoptosis of immortalized esophagus epithelial cells. METHODS: SHEE, an immortalized human fetal esophageal epithelial cell line induced by HPV18 E6E7, was cultivated in culture flasks and 24-well plates. Two experiment groups of cultured cells were treated with 1 and 5 mmol/L of sodium butyrate respectively for 4 days, and one group of untreated cells set aside as control. The numbers of cloned cells were calculated. The ultra-structure of SHEE cells was examined by transmission electron microscopy (TEM). The cell cycle and number of apoptotic cells were measured by flow cytometry, Ki-67 and cytokeratin of cells were detected by immunohistochemistry method and F-actin of cells labeled with phalloidin was examined by laser confocal scanning microscopy. RESULTS: Colony formations showed a significant decrease in the 2 experiment groups after 4 days of culture (P < 0.01). In the 1 mmol/L group, the cells at S phase were diminished and arrested at G(0)/G(1) phase. Compared with control group, Ki-67 positive cells were found decreased, while F-actin and cytokeratin were increased. Apoptotic cells in 5 mmol/L group were increased markedly. CONCLUSIONS: Sodium butyrate may induce SHEE cells growth arrest, differentiation and apoptosis. The effects depend on sodium butyrate concentration and time of exposure. Whether it can be used in combination with other anticancer drugs should be further studied.

Actins↗

PubMed2001

[The difference of intracellular cytokines produced by different lymphocyte subsets of cord blood and adult peripheral blood].

OBJECTIVE: To explore the difference of intracellular cytokines between cord blood and adult peripheral blood and elucidate its significance for GVHD. METHOD: Different lymphocyte subsets were categorized in cord and adult peripheral blood by monoclonal antibodies with 3 color fluorescence using flow cytometry. The IL-2, TNF-alpha and IFN-gamma produced by various lymphocyte subsets were compared between the two groups. RESULT: (1) In cord blood, dominant T cells were CD(4)(+)CD(45RA)(+), while the major T cells were both CD(4)(+)CD(45RO)(+) and CD(8)(+)CD(45RO)(+) in adult peripheral blood. (2) The quantities of IL-2, TNF-alpha and IFN-gamma produced by cord blood lymphocytes were lower than that of adult peripheral blood lymphocytes. Moreover, the majority of cells that produced cytokines in the cord blood were CD(4)(+)CD(45RA)(+), but in adult peripheral blood were mainly CD(4)(+)CD(45RO)(+) and CD(8)(+)CD(45RO)(+). CONCLUSION: As compared with adult peripheral blood, the cord blood not only possessed different proportion of lymphocyte subsets, but also significant low level of cytokines. The differences of various lymphocyte subset proportions and lower level of cytokines in cord blood probably related to the lower incidence of GVHD in cord blood stem cell transplantation.

Adult↗

PubMed2001

Long-term colonization levels of Helicobacter hepaticus in the cecum of hepatitis-prone A/JCr mice are significantly lower than those in hepatitis-resistant C57BL/6 mice.

Helicobacter hepaticus infection causes hepatitis in A/JCr mice but mild or no disease in C57BL/6 mice. Colonization of H. hepaticus in the cecum of experimentally infected A/JCr and C57BL/6 mice was quantified by use of real-time polymerase chain reaction (PCR) analysis with primers for the H. hepaticus cdtB gene and mouse 18srRNA. Eight-week-old mice were experimentally (n = 48) or sham (n = 24) infected with H. hepaticus, then were necropsied 6 months after infection. Liver specimens from experimentally infected mice had negative results of PCR analysis for H. hepaticus; thus, real-time quantification was not attempted. Quantitative PCR analysis of H. hepaticus in cecal specimens indicated that C57BL/6 mice were colonized to a greater extent than were A/JCr mice (P < 0.006). Appreciable typhlitis was not observed, but was consistent with that of previous reports; A/JCr mice developed more severe parenchymal necrosis, portal inflammation, and phlebitis in the liver (P < 0.0001), with mild disease observed in infected C57BL/6 mice. Thus, hepatitis in A/JCr mice caused by H. hepaticus infection is associated with significantly lower colonization levels of H. hepaticus in the cecum, compared with those of hepatitis-resistant C57BL/6 mice. Host responses of A/JCr mice that limit cecal colonization with H. hepaticus may have important roles in the pathogenesis of hepatic lesions.

Animals↗

PubMed2001

[Application of posterior canal wall reconstruction and mastoid obliteration].

OBJECTIVE: To explore the obliteration of the old mastoid cavity and reconstruction of the posterior canal wall after radical mastoidectomy. METHOD: Posterior canal wall reconstruction and mastoid obliteration of 11 ears of 10 patients with old mastoid cavity for 1 to 6 years after radical mastoidectomy were done using the pedicle postauricular composite skin flap (PPCSF), and their tympanoplasty were performed at the same time. Follow-up was performed at 3 to 30 months. RESULT: All PPCSFs survived. The old mastoid cavity of 11 ears vanished and reconstructed posterior canal wall remained in normal position without retraction. The drying ear time took 2 to 3 weeks postoperatively, and the symptoms of the radical cavity disease after radical mastoidectomy were cleared up nearly, and the average hearing threshold decreased 13.6 dB HL. The otorrhea and perforation of tympanic membrane resulted from infection happened to 1 of 11 ears three month after the operation. CONCLUSION: The PPCSF is an effective method in the obliteration of old mastoid cavity and reconstruction of the posterior canal wall. It can reduce drying ear time postoperatively, treat the radical cavity disease after radical mastoidectomy and is beneficial to the tympanoplasty at the posterior external at the same time.

Adolescent↗

PubMed2001

[Surgical treatment and reconstruction for the patients with advanced-stage tonsillar cancer].

OBJECTIVE: To investigate the operative approach and reconstruction for the patients with advanced-stage tonsillar cancer. METHOD: 7 cases with advanced-stage tonsillar cancer were operated from Dec. 1994 to May 1999. Among them, 5 cases were operated through combined neck-mandible-oral cavity approach (CNMOCA) and with immediate reconstruction. Forearm free skin (FFS) flaps were applied in 3 cases. Pectoralis major myocutaneous (PMM) flaps were applied in 2 cases. 2 other cases were operated separately through approach of oral cavity or lateral pharynx. 6 cases were operated with radical neck dissection. RESULT: 5 cases who were operated through CNMOCA or with reconstruction were followed up from 1 year to 5 years and 3 months. They had not recurrence of tumor and complication. All had function recovery of speech. Swallowing or appearance is satisfactory in the 3 cases with FFS flaps. 2 Other cases died as recurrence of tumor in 1 year and 2 years and 10 months post-operation. CONCLUSION: CNMOCA is able to provide a good exposure method to remove the extensive tumors completely for the patients with advanced stage tonsillar cancer. It is necessary to reconstruct immediately for the patients.

Adult↗

PubMed2001

[The effects of BDP on the inflammatory cells in nasal secretions of the patients with allergic rhinitis].

OBJECTIVE: To study the effects of beclomethasone dipropionate (BDP) on the inflammatory cells in nasal secretions of the patients with allergic rhinitis. METHOD: The variation of intercellular RNA and RNA/DNA ratio of the eosinophils, neutrocyte and lymphocyte in the nasal secretions were observed under the laser scanning confocal microscopy and technology of fluorescence. RESULT: The scanning images displayed that either in eosinophils or in neutrocyte, the fluorescence signal of intercellular RNA was significantly decreased after BDP treatment, and the intercellular RNA/DNA ratio was significantly reduced (eosinophils group P < 0.001, and neutrocyte group P < 0.01). The fluorescence singal of lymphocyte intercellular RNA and RNA/DNA ratio were not significantly changed (P > 0.05). CONCLUSION: BDP can reduce the content of intercellular RNA of the eosinophils and neutrocyte. The anti-inflammation function of BDP is realized by regulating the intercellular RNA synthesize and/or RNA degradation, and by inhibiting the intercellular inflammatory medium production. BDP does not directly influence the intercellular RNA metabolize of the lymphocyte.

Adult↗

PubMed2001

[Introduction of Vitreoscilla hemoglobin gene in a recombinant E. coli for PHB production].

Vitreoscilla hemoglobin gene (vgb) was introduced into the recombinant Escherichia coli VG1(pTU14) for production of poly-beta-hydroxybutyrate (PHB), in order to enhance the oxygen uptake of strain from molecular level and to solve the problem of oxygen limitation in process of fermentation. The carbon monoxide difference spectra analysis of Vitreoscilla hemoglobin (VHb) showed that vgb could be successfully expressed in VG1 (pTU14), and this expression was under the regulation of dissolved oxygen (DO). The higher amounts of VHb could be got correspond to the lower level of DO. Because of the introduction of vgb, cell growth and PHB accumulation of VG1 (pTU14) were all strongly promoted during the process of batch culture.

Bacterial Proteins↗

PubMed2001

[Effect of Ce3+ on reactive oxygen species in cells].

The effect of Ce3+ on the content of (reactive oxygen species ROS) in hepatocytes and V79 cells was studied with microfluorometry. The results showed that Ce3+ could enhance the concentration of ROS in hepatocytes in high dose and reduce the concentration of ROS in low dose. These results suggested that Ce3+ might decrease the damage of lipid peroxidation and DNA in low dose and might increase the damage of lipid peroxidaion and DNA in high dose.

Animals↗

PubMed2001

[Determination of trace as in health-giving drink by AA-670 atomic absorption spectrophotometry attached VA-90 atomization].

A new method has been developed for the determination of trace metal As in health-giving drink by AA-670 atomic absorption spectrophotometry attached VA-90 atomization. The method is convenient to determine element in water. The results show that the method has good precision and accuracy. The detection limit is 2 ng.L-1 for As. The relative standard deviation is 5.4%-6.1%, and the rates of recovery is 87.5%-115%. This method has been applied to the determination of health-giving drink with satisfactory results.

Arsenic↗

PubMed2001

[Determination of nickel in artificial cream by flame atomic absorption spectrometry].

This paper describes a new method for the determination of nickel in artificial cream by flame atomic absorption spectrometry. Compared with the others, the process of sample treatment by HNO3-H2SO4 is simple, and the operation is easy. The results show that the method offers good precision and accuracy. The relative standard deviation is 3.04% and the rate of recovery is 97.7%.

Food Contamination↗

PubMed2001

[Enhancement of bacillus Calmette-Guerin attachment to the bladder wall: experimental study].

OBJECTIVE: To provide experimentally a scientific basis for enhancement of bacillus Calmette-Guerin (BCG) antineoplastic effect. METHODS: Thirty rabbits were equally divided into five groups (groups A, B, C, D, and E) and the bladder mucosa of every rabbit was injured by electrocautery, cryocautery and incision on the left lateral wall, right lateral wall and posterior wall respectively. Then different drugs were instilled into bladders. Group A: pure phosphate-buffered sodium instillation (PBS); group B: PBS and radiolabeled BCG (3H-BCG) instillation; group C and group D: epsilon-aminocaproic acid or para-aminomethyl benzoic acid and 3H-BCG instillation; group E: heparin and 3H-BCG instillation. After instillation, every injured bladder wall and non-injured wall (anterior wall of bladder) were surgically removed and digested. The quantity of BCG adherence was determined by liquid scintillation counter. RESULTS: The quantity of BCG attached to injured bladder wall was significantly higher than that of non-injured wall (P < 0.001). The mean level of group C or group D was significantly higher than that of group B (P < 0.001) while the mean level of group E was significantly lower than that of group B (P < 0.001). CONCLUSION: For experimental rabbits, intravesical instillation of fibrin clot stabilizer EACA or PAMBA can enhance BCG attachment to the bladder wall while fibrin clot inhibitor heparin inhibits it.

Administration, Intravesical↗