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Lei Yang

Publications and source records attributed to Lei Yang.

At least 73 records · Page 4Linked to original sources
PubMed2005

Prevention and treatment of rejection after simultaneous pancreas-kidney transplantation.

OBJECTIVE: To explore methods of preventing and reversing rejection after simultaneous pancreas-kidney (SPK) transplantation. METHODS: Seventeen patients underwent SPK transplantation from September 1999 to September 2003 were reviewed retrospectively. Immunosuppression was achieved by a triple drug regimen consisting of cyclosporine, mycophenolate mofteil (MMF), and steroids. Three patients were treated with anti-CD3 monoclone antibody (OKT3, 5 mg x d(-1)) for induction therapy for a mean period of 5-7 days. One patients received IL-2 receptor antibodies (daclizumab) in a dose of 1 mg x kg(-1) on the day of transplant and the 5th day posttransplant. One patient was treated with both OKT3 and daclizumab for induction. RESULTS: No primary non-functionality of either kidney or pancreas occurred in this series of transplantations. Function of all the kidney grafts recovered within 2 to 4 days after transplantation. The level of serum creatinine was 94 +/- 11 micromol/L on the 7th day posttransplant. One patient experienced the accelerated rejection, resulting in the resection of the pancreas and kidney grafts because of the failure of conservative therapy. The incidence of the first rejection episodes at 3 months was 47.1% (8/17). Only the kidney was involved in 35.3% (6/17); and both the pancreas and kidney were involved in 11.8% (2/17). All these patients received a high-dose pulse of methylprednisone (0.5 g x d(-1)) for 3 days. OKT3 (0.5 mg x d(-1)) was administered for 7-10 days in two patients with both renal and pancreas rejection. All the grafts were successfully rescued. CONCLUSION: Rejection, particularly acute rejection, is the major cause influencing graft function in SPK transplantation. Monitoring renal function and pancreas exocrine secretion, and reasonable application of immunosuppressants play important roles in the diagnosis and treatment of rejection.

Adult↗
PubMed2005

[Inhibition of the expression of prostate specific antigen by curcumin].

AIM: To study the effect of curcumin on the expression of prostate specific antigen (PSA). METHODS: AXSYM system-chemical luciferase method was used to examine the content of PSA in prostate cancer cell lines, LNCap after treated with different doses of curcumin. pGL3-PSA luciferase expression vector, containing 640 bp DNA of PSA gene 5' promoter region was constructed and transfected into LNCap cell with lipofectin. Through detecting the activity of luciferase, the effect of curcumin on the promoter of PSA was studied. Western blotting was used to detect expression of androgen receptor (AR) in LNCap cell with different concentrations of curcumin. RESULTS: The expression of PSA was inhibited and activity of luciferase was reduced by curcumin. There was also significant difference in AR expression as shown by Western blotting experiment after treatment of different doses of curcumin. CONCLUSION: Through inhibiting AR expression, curcumin reduced the function of PSA promoter and inhibited PSA protein expression.

Antineoplastic Agents↗
PubMed2005

[A case-control study on risk factor of Kaposi's sarcoma in Xinjiang].

OBJECTIVE: To analyse related risk factors of classic Kaposi' s sarcoma in Xinjiang. METHODS: A 1:4 case-control study was used and the conditional logistic regression model was performed in this study. Cases were followed up in Xinjiang while controls were selected by the same sex, nation and age within 5 years with cases. RESULTS: Interleukin-6,vascular endothelial growth factor, beta-MG, neopterin, human herpevirus 8, were found to be associated with Kaposi's sarcoma risk in one-way variance model while beta2 -MG and human herpevirus 8 entered the multiple conditional logistic regression model, and their ORs were 1.002(95%CI: 1.000-1.003), 81.041 (95%CI: 1.790-3669.620). CONCLUSION: There was a correlate relationship between beta2 -MG and classic Kaposi's sarcoma being found that human herpevirus 8 exposure related factors seemed to have played important roles on classic Kaposi's sarcoma in Xinjiang.

Adult↗
PubMed2004

[Analysis of rejection after simultaneous pancreas-kidney transplantation].

OBJECTIVE: To explore methods of preventing and reversing rejection after simultaneous pancreas-kidney transplantation (SPK). METHODS: Seventeen patients performed SPK operation from Sep, 1999 to Sep, 2003 were reviewed retrospectively. Immunosuppression was achieved by triple regimen consisting of cyclosporine, mycophenolate mofetil (MMF)/azathioprine and steroid. 2 patients were treated with Dalizumab, the other three patients used OKT3 as immune induction. RESULTS: 1 patient experienced the accelerated rejection, the pancreas and kidney grafts were resected because of failure of conservative therapy. 8 patients experienced renal acute rejection, 2 cases suffered from pancreas acute rejection at the same time. All these patients received daily high dose pulse steroid for 3 days. OKT3 was administered in 2 patients with steroid resistance rejection. All the grafts were successfully rescued. CONCLUSIONS: Reasonable application of immunosuppression after SPK operation and adoption of systemic measures which can reduce sensitivity of high risk receptor before SPK operation are the effective methods of preventing and treating rejection.

Administration, Oral↗
PubMed2004

Lattice scale-free networks with weighted linking.

Recently, models of the scale-free (SF) networks on lattices were investigated, which consider the influence of the embedded space on the networks. Since a lot of real networks exist on the 2D global surface, it is helpful to discuss these models. In this paper, based on the lattice SF networks model, a linking weight is added, thus an additional parameter which can control the clustering coefficient is introduced. Depending on the linking weight, the properties of the model change smoothly from the lattice SF model to the SF random graphs.

Journal Article↗
PubMed2004

[Instability of C1,2 treated with transcutaneous anterior lateral mass fixation and bone grafting].

OBJECTIVE: Creating the method of transcutaneous anterior lateral mass fixation for instability of C(1,2). METHODS: The regular and safe angle and the distance between the median margin of vertebral artery and median line of superior and inferior margin of axis were measured with computerized tomography. Fifteen cases of C(1,2) instability including 7 cases atlanto-axial dislocation, 3 cases of Jefferson's fracture, 1 case of dental fracture and dislocation and 4 cases of fractures of anterior arch of C1 were treated with pertacuneous anterior lateral mass screws and bone grafting with new-designed hole instrumentations according to the measurement of 40 normal atlanto-axial vertebrae. RESULTS: In posterior-anterior ray the regular angle was 24.0 degrees +/- 3.7 degrees (right side), and 23.8 degrees +/- 1.8 degrees (left side); safe angle is 15.2 degrees - 30.3 degrees (left side) and 14.8 degrees - 32.1 degrees (right side), respectively. The distance between the median margin of vertebral artery and median line of superior and inferior margin of vertebral artery and median line of superior and inferior margin of lateral mass was (5.6 +/- 2.2) mm (right) and (5.8 +/- 1.9) mm (left). In lateral ray the regular angle was 24.1 degrees +/- 1.8 degrees, and safe angle 12.6 degrees - 26.8 degrees. All cases reach a satisfactory result of fixation without the injury of vertebral artery, spinal cord and esophagus. The acupuncture point recovers without infection. CONCLUSIONS: This operation procedure for instability of C(1,2) has the advantage of less trauma and bleeding, simply operation and bone grafting at the same time. The operation procedure is safe with reasonable instrument and selecting the correct puncture point, angle and depth.

Adult↗
PubMed2004

Smad4 protein stability is regulated by ubiquitin ligase SCF beta-TrCP1.

Smad4 is a key intracellular mediator for the transforming growth factor-beta (TGF-beta) superfamily of growth factors and is also an important tumor suppressor. The receptor-regulated Smad (R-Smad) proteins are regulated by ubiquitin-mediated degradation, yet the precise control of Smad4 protein stability is unclear. We have identified SCF(beta-TrCP1), a ubiquitin (E3) ligase, as a critical determinant for the protein degradation of Smad4 protein. F-box protein beta-TrCP1 in this E3 ligase interacts with Smad4 both in yeast and in mammalian cells, but has no interaction with Smad2 and has weak interaction with Smad3. The beta-TrCP1/Smad3 interaction was abolished by Smad4 gene silencing, indicating the interaction is indirect and is through Smad4. Ectopic expression of SCF complex containing beta-TrCP1 is sufficient to induce the ubiquitination and degradation of Smad4. Furthermore, small interfering RNA-triggered endogenous beta-TrCP1 suppression increases the expression of Smad4 protein. Consistent with these results, cells that overexpress the SCF complex display an inhibited TGF-beta-dependent transcriptional activity and an impaired cell cycle arrest function. Thus, SCF(beta-TrCP1) abrogates TGF-beta function in vivo by decreasing Smad4 stability.

Blotting, Western↗
PubMed2004

Effects of Huangqi (Hex) on inducing cell differentiation and cell death in K562 and HEL cells.

Huangqi (Astragalus membranaceus), a traditional Chinese medicine, has been used to ameliorate side effects of cancer chemotherapy in China. However, little is known about its molecular mechanisms. Here we show that induction of K562 or HEL cells with 1.5 mg/ml of Huangqi (Hex) (Components extracted from Huangqi) for 3-5 d results in the expression of beta-globin gene in both cell lines and leads to terminal differentiation. Moreover, the apoptosis in HEL cells can be induced by increasing concentration of Huangqi (Hex) to 4.5 mg/ml for 3-5 d. Upregulation of Apaf-1, caspase-3 and acetylcholinesterase (AChE) in HEL cells may play a crucial role in the process of apoptosis. The prospect of inducing expression of adult (beta) globin gene and apoptosis selectively in cancer cells is obviously attractive from a therapeutic point of view.

Acetylcholinesterase↗
PubMed2004

Identification of a novel variant CYP2C9 allele in Chinese.

OBJECTIVES: Cytochrome P450 (CYP) 2C9 metabolizes about 16% of drugs in current clinical use, including lornoxicam and tolbutamide. SNPs in the CYP2C9 gene have increasingly been recognized as determinants of the metabolic phenotype that underlies interindividual and ethnic differences. METHODS: The present study focused on a Chinese poor metabolizer (PM) whose apparent genotype (CYP2C9*1/CYP2C9*3) did not agree with his PM phenotype for both lornoxicam and tolbutamide. By sequencing his CYP2C9 gene, we identified a new variant CYP2C9 allele involving a T269C transversion in exon 2 that leads to a Leu90Pro substitution in the encoded protein. RESULTS: The CYP2C9 genotype analysis in the family of the poor metabolizer showed the new exon 2 change and CYP2C9*3 occurred on different alleles. Thus, the PM status of this subject could be attributed to his being heterozygous for the CYP2C9 T269C allele together with the CYP2C9*3. Frequency analysis in 147 unrelated Chinese males indicated approximately 2% of the Chinese population carry the allele. CONCLUSION: This study suggests that this novel CYP2C9 allele was correlated with reduced plasma clearance of drugs that are substrates for CYP2C9.

3' Untranslated Regions↗
PubMed2004

[Evaluation of operation and anesthesia on hemodynamic variables in patients undergoing elective abdominal surgery by noninvasive thoracic bioimpedance technique].

OBJECTIVE: To analyse and discuss the effects of elective abdominal operation and anaesthesia on patients' cardiac output via noninvasive thoracic bioimpedance technique. METHODS: Noninvasive monitoring system HeMo-601 was applied to detect the hemodynamic variables of 32 elective abdominal surgery patients. The clinical data of cardiac output (CO), cardiac index (CI), cardiac working per minute (CW), left ventricular end-diastolic pressure (LVEDP), stroke volume (SV), cardiac stroke working (SW) and heart rate (HR) were analysed at 1 hour before operation, 4-6 hours after operation and 24 hours after operation, respectively. RESULTS: No significant differences were found in CO, CI, CW and LVEDP between various time points and preoperation (all P>0.05). SV and SW at 4-6 hours after operation were significant lower than those before operation (all P<0.05). Whereas, SV and SW at 24 hours after operation were no significant differences compared with those before operation (all P>0.05). As compared with preoperation, HR at 4-6 hours after operation was significantly faster (P<0.05). However, there was no significant difference in HR between 24 hours after operation and preoperation (P>0.05). CONCLUSION: The reductions in SV and SW at 4-6 hours after operation might be a result of anaesthesia that could weaken the contraction of heart. The presence of rapidness of HR at 4-6 hours after operation might be a compensatory mechanism for the decreases in SV and SW. Therefore, optimizing adequate infusion by the greatest extent during and after operation is very crucial for the maintenance of CO, CI and tissue perfusion.

Abdomen↗
PubMed2004

[Clinical analysis of complications after non- invasive positive pressure ventilation and an inquiry into the respiratory treatment strategy in patients with SARS].

OBJECTIVE: To analyze the clinical data of severe acute respiratory syndrome (SARS) patients with pneumothorax and mediastinal emphysema occurring after the non-invasive positive pressure ventilation (NIPPV), and to inquire into relevant strategy in respiratory treatment in the SARS patients. METHODS: Twenty-seven serious cases of SARS undergone NIPPV were analyzed retrospectively. RESULTS: Pneumothorax and mediastinal emphysema occurred in 7 of 27 serious cases of SARS with NIPPV, and mediastinal emphysema occurred in 1 of 189 cases of SARS without mechanical ventilation (MV). The incidence of pneumothorax and mediastinal emphysema in serious cases of SARS with NIPPV was significantly higher (chi2=25.052, P<0.01) than that in cases of SARS without receiving MV. The peripheral blood oxygen saturation level was not changed significantly after reasonable adjustment of ventilation pressure and increase in oxygen concentration inhaled. Seven cases of pneumothorax and mediastinal emphysema improved gradually. CONCLUSION: The incidence of pneumothorax and mediastinal emphysema in serious SARS patients with NIPPV is significantly higher than that in SARS patients without receiving MV. This might be related to SARS related pulmonary injuries, intensive cough and high mechanical ventilation pressure. The pneumothorax and mediastinal emphysema improve gradually in all cases after reasonable adjustment of mechanical ventilative pressure. So when NIPPV is used in the treatment of serious SARS patients to improve hypoxemia, optimized mechanical ventilative pressure should be acquired in order to avoid pneumothorax and mediastinal emphysema.

Adult↗
PubMed2004

[Expression of Smads in lung tissue of quartz-induced pulmonary fibrosis in mice].

OBJECTIVE: To observe Smads protein expression in lung tissue of quartz exposed mice and to explore its association with pulmonary fibrosis in silicosis. METHODS: The experimental mice were divided into control and quartz groups. 0.2 g/kg weight of quartz was injected intratracheally in quartz group. Samples were collected at the 1st, 3rd, 5th, 7th, 14th and 28th day after injection. Immunohistochemical methods with quantitative image analysis were used to assay the protein expression of transforming growth factor beta(1) (TGF-beta(1)), Smad 2/3, Smad 4, and Smad 7 protein levels. Protein expression level is presented by positive unit (PU). RESULTS: Smad 2/3 protein expression increased from day 3, reaching its peak level in day 14 [(42.2 +/- 2.4) PU], and decreased gradually. The elevation of Smad 4 protein level began from day 5, and the highest degree came into day 14 [(40.0 +/- 1.8) PU], decreased thereafter. The expression of Smad 7 presented a decreasing tendency at the beginning and reaching the lowest level in day 14 [(33.5 +/- 3.3) PU]. It seemed to elevate in day 28, but was still lower than the controls. There were positive correlation between Smad 2/3, Smad 4 and TGF-beta(1) (r = 0.91, r = 0.71, respectively, P < 0.05) and also between Smad 2/3 and hydroxyproline contents of lung tissue (r = 0.85, P < 0.05) except Smad 7. CONCLUSION: Smad protein may have certain association with pulmonary fibrosis in silicosis.

Animals↗
PubMed2004

[The dynamic changes of collagen fiber in quartz-induced pulmonary fibrosis in mice with picrosirius red plus polarized microscopy in vivo].

OBJECTIVE: To investigate the use value of picrosirius red staining plus polarized microscopy to observe the dynamic changes of collagen fiber in lung fibrosis in silicotic mice model. METHODS: The experimental mice were divided into control and quartz groups. 0.2 g/kg weight of quartz was injected intratracheally in quartz group. Lung tissues were collected at the 1st, 3rd, 5th, 7th, 14th and 28th day after injection respectively. Lung tissue slides were stained with picrosirius red. With the aid of polarized microscope, image analysis software, the distribution and change of type I and type III collagen could be qualitatively and quantitatively analyzed. Lung tissue hydroxyproline was determined by chloramines T method. RESULTS: In early stage the predominant increment was type III collagen, but in late stage type I was predominant. The contents of both type collagen tended to increase as postexposure time prolonged. The time course of the ratio of type I to type III showed increasing trend, and there was a statistical significance on day 28 (1.49 +/- 0.39 vs 0.59 +/- 0.24, P < 0.05). The total area of collagen was positively correlated with hydroxyproline concentration of lung tissue (r(2) = 0.928 5, P < 0.01). CONCLUSION: Picrosirius red staining combined with polarized microscopy and digital image processing is a useful method to elucidate collagen accumulation, distribution and subtype ratio in silicosis.

Animals↗
PubMed2004

[Influence of cage culture in Yaling Bay on water environment].

On the basis of on-the-spot survey and analysis of water quality and bed mud in different cage culture section from April of 2002 to January of 2003, the analysis result indicate that the main influence of cage culture on environment are that: (1) It increase the content of nutrition salt, BOD, COD, organic matter and TSS, especially inorganic-nitrogen, inorganic-phosphor and ammonia nitrogen; (2) It enrich N, P, sulphide and organic matter in sediment. The most obvious is nitrogen, sulphide and ammonia nitrogen, next is total nitrogen and organic matter.

Animal Feed↗
PubMed2004

[Analysis on pneumoconiosis characteristic and its prediction in one coal mine].

OBJECTIVE: We aimed to investigate the characteristic of pneumoconiosis on coal miners and provide scientific evidences for its prevention. METHODS: To analyze the data of pneumoconiosis from one coal mine with the historical study and to predict its development tendency by the grey model of GM (1,1). RESULTS: (1) The year of work experience of pneumoconiosis (stage I) was 19.9 years and the age of its diagnosis (stage I) was 51.4 years. There was an obvious tendency that they became longer with years' back-shift. (2) During near forty years, the progression rates of pneumoconiosis from stage I to II and II to III were 13.6% and 11.2%, and the mean time was 8.3 and 8.1 years, respectively. It was obvious that the progression rate decreased gradually and the span prolonged with years' back-shift. (3) The complication rate of pneumoconiosis with lung tuberculosis was 12.5% and it increased with the progression of pneumoconiosis. The rate in dead cases was significantly higher than that in live cases (P < 0.01). (4) The sequence of death causes was pneumoconiosis (20.0%), lung tuberculosis (18.3%), chronic cor pulmonale (17.9%), and pulmonary carcinoma (9.0%), et al. (5) It was predicted that there would be 28 new cases every year during 2001-2020 years and the accumulated numbers of pneumoconiosis would be 2854 cases in 2020, but with a downward trends in the prevalence of -1.7%. CONCLUSION: It was suggested that the prevalence of pneumoconiosis should decrease obviously. However, it still remains a challenge about the task of effectively preventing and curing it or its complication.

Adult↗
PubMed2004

[Analysis of surface electromyography on repetitive lifting task-induced fatigue of back muscles].

OBJECTIVE: Using surface electromyography (SEMG) technique to evaluate repetitive lifting task-induced fatigue of back muscles. METHODS: Thirteen volunteers lifted and lowered an 8 kg weight from floor to waist level for 100 times. Fatigue in the erector spinae muscles was quantified by comparing the frequency content of the EMG signal during static contractions performed before, and immediately after the 100 lifts. RESULTS: EMG average amplitude rose gradually during 100 lifts, the difference was significant at T10 right (P < 0.05) and L3 left (P < 0.01), the difference was not significant at T10 left and L3 right (P > 0.05). The median frequency intercept at T10 right, T10 left, L3 right, L3 left erector spinae muscles decreased by 2.0% (P > 0.05) 10.9% and 29.9% (P < 0.05), 27.9% (P < 0.01), respectively. The mean power frequency intercept decreased by 9% at L3 left erector spinae muscle (P < 0.05), the decrease was not statistically significant at other sites (P > 0.05). CONCLUSION: Repetitive lifting may induce measurable fatigue in the erector spinae muscles. Erector spinae muscle at L3 is more easily fatigued than at T10. Using the median frequency intercept to assess muscle fatigue is more sensitive than using mean power frequency intercept.

Adult↗
PubMed2004

[Estimation of intramuscular load of the upper limb in static postures and repetitive work by surface electromyography].

OBJECTIVE: To evaluate the intramuscular loads of the upper limb during static postures and repetitive work by surface electromyography. METHODS: Twenty-six male college student volunteers were recruited for the experiment. The surface electromyography (SEMG) singal were recorded from the brachioradialis, biceps brachii, deltoid and trapezius of right arm during static postures including forward elevating, abducting, extending and a repetitive performance at different height of the bench, and root mean square (RMS) values were educed from the singal. RESULTS: The SEMG amplitudes from forward elevating and abducting were in direct proportion to the angle of the elevating and abducting (r > 0.9, P < 0.01). The maximal voluntary electrical activation (MVE) of the deltoid were 6.4%, 10.1%, 12.6%, 16.2% and 20.8% while the arm elevated forward at an angle of 0 degrees , 45 degrees , 90 degrees , 135 degrees and 180 degrees respectively. The repetitive work showed that the height of the bench and the duration had more effects on deltoid and trapezius than the other muscles. The MVE% of the deltoid were 13.0%, 14.4% and 15.6% while the bench was 74, 79 and 84 cm in height respectively (P < 0.01). CONCLUSION: SEMG which is suitable for determining and reflecting the muscle strain during static postures and repetitive work may be a reasonable indicator for the assessment of manual workload and the ergonomic design.

Arm↗