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991.
Gene directed enzyme pro-drug therapy (GDEPT) is one of the adjuvant therapeutic regimens for advanced prostate adenocarcinoma, and this research intended to explore how to apply targeting therapy of prostate adenocarcinoma under the mediation of a promoter/enhancer of prostate-specific membrane antigen (PSMA(EP)) as a specific regulatory element. Recombinant adenoviruses (Ad-PSMA(E-P)-enhanced green fluorescent protein [EGFP], Ad-CMV-EGFP, Ad-PSMA(E-P)-CD, and Ad-CMV-CD) were constructed and could express cytosine deaminase (CD) or the EGFP reporter gene driven by a PSMA(EP) or cytomegalovirus (CMV) promoter. LNCaP, CL-1, MCF-7, and A549 were infected with CD-produced recombinant adenoviruses and treated with pro-drug 5-fluorocytosine (5-FC) in vivo and vitro; then, the growth inhibition of the cells and the cell cycle variation were assessed by an [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay and flow cytometry. Growth suppression of the xenograft tumor was also adopted to evaluate the efficiency of the suicide system. Morphologic changes after treatment in vivo were assessed with hematoxylin and eosin staining. In the 4 examined cancer cell lines, PSMA-positive prostate cancer cells LNCap and CL-1 were exclusively sensitive to the Ad-PSMA(E-P)-CD/5-FC system. The S phase of cell cycle arrest was thought to be involved in the cytotoxicity of 5-fluorouracil (5-FU) converted from 5-FC by CD. CL-1 implanted Athymic BALB/c mice showed growth inhibition of tumors when they were treated with the Ad-PSMA(E-P)-CD/5-FC system without systemic conversion toxicity. The PSMA-based, CD-produced adenovirus, deserving further investigation in the future, might be a good candidate for targeting gene therapy of prostate adenocarcinoma.  相似文献   
992.
West R  Zhou X 《Thorax》2007,62(11):998-1002
BACKGROUND: Increasing smoking cessation rates is an important goal in preventing lung cancer and chronic obstructive pulmonary disease. Nicotine replacement therapy (NRT) has been found in clinical trials to improve the chances of success at stopping, but recent cross-sectional survey data have raised doubts as to whether it is effective when used by smokers making quit attempts unsupervised outside clinical trials. Because of biases inherent in cross-sectional surveys, this issue can only be adequately addressed using longitudinal studies. This paper reports the first study of its kind to examine the issue. METHODS: The ATTEMPT cohort is a multinational cohort study with data collection by the internet which recruited smokers of > or = 5 cigarettes per day aged 35-65 years who were intending to stop smoking within the next 3 months. Phase 1 began in spring 2003 and involved 2009 smokers from the USA, UK, Canada and France. Phase 2 involved 3645 smokers and included the same countries plus Spain. Follow-up assessments were carried out every 3 months. 492 smokers who made a quit attempt without formal behavioural support or bupropion in the first 3-month follow-up period were identified from phase 1, 357 of whom were followed up for a further 6 months. The phase 2 sample involved 906 smokers making quit attempts, 732 of whom were followed up. At baseline, demographic characteristics, smoking history and nicotine dependence were assessed. Smokers who made quit attempts were questioned on methods used to aid them. The main outcome measure was self-report of complete abstinence throughout both the 3-month periods following the quit date. RESULTS: 35.6% of smokers followed up in phase 1 and 29.6% of those followed up in phase 2 used NRT. The odds ratios comparing abstinence for 6 months in those using and those not using NRT, adjusting for nicotine dependence, were 3.0 (95% CI 1.2 to 7.5) for the phase 1 sample and 2.1 (95% CI 1.0 to 4.1) for the phase 2 sample. The difference in success rates between those using NRT and those not using it, adjusted for the Fagerstrom test for nicotine dependence (FTND) score, was 6% in the phase 1 sample and 3.7% in the phase 2 sample. The improved odds of success were not explicable in terms of motivation to use some form of aid to cessation or differential loss to follow-up. CONCLUSION: NRT use by smokers making self-initiated quit attempts without formal behavioural support is associated with improved long-term abstinence rates.  相似文献   
993.
Reconstruction after resection of tumor about the acetabulum represents a considerable challenge in reconstructive surgery. Between 1999 and 2003, three patients with periacetabular tumors underwent tumor resections (Ennecking type B) and pelvic ring reconstruction with microsurgical fibular flaps. Histological diagnosis showed osteosarcoma, giant cell tumor, and aneurysmoid bone cyst. All patients survived surgery without complications. The follow-up for patients ranged from 14 to 42 months. The average time for bone healing and full weight bearing was 13.6 weeks after surgery. In evaluations of the functional outcome using Enneking scoring system, two reached the score of excellent (>or= 23 points), and one reached the score of good (15 to 22 points). This report shows our experience in use of microsurgical fibular flaps for arthrodesis of the hip after periacetabular tumor resection, which restores the continuity of the pelvic ring with minimal shortening of the limb.  相似文献   
994.
995.
Thoracic ossification of ligamentum flavum (OLF) caused by skeletal fluorosis is rare. Only six patients had been reported in the English literature. This study reports findings from the first clinical series of this disease. This was a retrospective study of patients with thoracic OLF due to skeletal fluorosis who underwent surgical management at the authors' hospital between 1993 and 2003. Diagnosis of skeletal fluorosis was made based on the epidemic history, clinical symptoms, radiographic findings, and urinalysis. En bloc laminectomy decompression of the involved thoracic levels was performed in all cases. Cervical open door decompression or lumbar laminectomy decompression was performed if relevant stenosis was present. Neurological status was evaluated preoperatively, at the third day postoperatively, and at the end point of follow-up using the Japanese Orthopaedic Association (JOA) scoring system of motor function of the lower extremities. A total of 23 cases were enrolled, 16 (69.6%) males and 7 (30.4%) females, age ranging from 42 to 72 years (mean 54.8 years). All patients came from a high-fluoride area, and 22 (95.7%) had dental fluorosis. Medical imaging showed OLF together with ossification of many ligaments and interosseous membranes, including interosseous membranes of the forearm (18/23 patients 78.3%), leg (14/23 patients 60.9%), and ribs (11/23 patients 47.8%). OLF was classified into five types based on MRI findings: localized (4/23 patients 17.4%), continued (12/23 patients 52.2%), skip (3/23 patients 13.0%), combining with anterior pressure (2/23 patients 8.7%), and combining with cervical and/or lumbar stenosis (2/23 patients, 8.7%). Urinalysis showed a markedly high urinary fluoride level in 14 of 23 patients (60.9%). Patients were followed up for an average duration of 4 years, 5 months. Paired t-test showed that the JOA score was slightly but nonsignificantly increased relative to preoperative measurement 3 days after surgery (P = 0.0829) and significantly increased at the end of follow-up (P = 0.0001). In conclusion, Fluorosis can cause ossification of thoracic ligamentum flavum, as well as other ligaments. Comparing with other OLF series, a larger number of spinal segments were involved. The diagnosis of skeletal fluorosis was made by the epidemic history, clinical symptom, imaging study findings, and urinalysis. En bloc laminectomy decompression was an effective method.  相似文献   
996.
Zhu Y  Zhou XY  Yao XD  Dai B  Ye DW 《BJU international》2007,100(1):204-208
OBJECTIVE: To evaluate the prognostic significance of p53, Ki-67, epithelial cadherin (E-cadherin) and matrix metalloproteinase-9 in primary penile cancer, as the presence of lymph node metastasis and long-term survival are hard to define in penile squamous cell carcinoma. PATIENTS AND METHODS: Paraffin-embedded primary tumour samples were obtained from 73 Chinese patients who had penile amputation and regional lymphadenectomy. The expression of molecular markers was determined by immunohistochemistry. Logistic regression was used to identify factors associated with lymph node metastasis, and a Cox proportional-hazards model was used to measure cancer-specific survival (CSS). RESULTS: Thirty (41%) patients presented with nodal disease and the 3-year CSS rate for all patients was 72%. Lymph node metastasis was significantly correlated with tumour stage, histological grade, lymphatic and vascular embolization, and the expression of p53, Ki-67 and E-cadherin. By multivariate analysis, tumour embolization and the expression of p53 were independent predictors of metastasis. Survival analysis showed that the expression of p53 was an independent prognostic factor for CSS. In stage T1 tumours, high expression of p53 was significantly associated with metastasis and poor survival. CONCLUSION: Lymphatic and vascular embolization, and p53 immunoreactivity, are helpful in establishing the probability of lymph node metastasis. The expression of p53 is an independent predictor of CSS in Chinese patients with penile cancer. In stage T1 tumours, p53 staining is an important variable determining the prognosis and treatment outcome.  相似文献   
997.
Nephronophthisis-associated ciliopathies   总被引:7,自引:0,他引:7  
Nephronophthisis (NPHP), an autosomal recessive cystic kidney disease, represents the most frequent genetic cause of end-stage kidney disease in the first three decades of life. Contrary to polycystic kidney disease, NPHP shows normal or diminished kidney size, cysts are concentrated at the corticomedullary junction, and tubulointerstitial fibrosis is dominant. NPHP can be associated with retinitis pigmentosa (Senior-L?ken syndrome), liver fibrosis, and cerebellar vermis aplasia (Joubert syndrome) in approximately 10% of patients. Positional cloning of six novel genes (NPHP1 through 6) as mutated in NPHP and functional characterization of their encoded proteins have contributed to the concept of "ciliopathies." It has helped advance a new unifying theory of cystic kidney diseases. This theory states that the products of all genes that are mutated in cystic kidney diseases in humans, mice, or zebrafish are expressed in primary cilia or centrosomes of renal epithelial cells. Primary cilia are sensory organelles that connect mechanosensory, visual, osmotic, and other stimuli to mechanisms of cell-cycle control and epithelial cell polarity. The ciliary theory explains the multiple organ involvement in NPHP regarding retinitis pigmentosa, liver fibrosis, ataxia, situs inversus, and mental retardation. Mutations in NPHP genes cause defects in signaling mechanisms, including the noncanonical Wnt signaling pathway. The "ciliopathy" NPHP thereby is caused by defects in tissue differentiation and maintenance as a result of impaired processing of extracellular cues. Nephrocystins, the proteins that are encoded by NPHP genes, are highly conserved in evolution. Positional cloning of additional causative genes of NPHP will elucidate further signaling mechanisms that are involved, thereby establishing therapeutic approaches using animal models in mouse, zebrafish, and Caenorhabditis elegans.  相似文献   
998.
OBJECTIVE: To test the hypothesis that administration of ghrelin attenuates inflammatory responses in sepsis through vagal nerve stimulation. SUMMARY BACKGROUND DATA: Ghrelin has been demonstrated to possess multiple functions, including stimulation of the vagus nerve. Our recent study has shown that plasma levels of ghrelin were significantly reduced in sepsis; and ghrelin administration improved organ perfusion and function. However, it remained unknown whether ghrelin also decreases proinflammatory cytokines in sepsis and, if so, whether the down-regulatory effect of ghrelin is mediated by activation of the vagus nerve. METHODS: Male rats were subjected to sepsis by cecal ligation and puncture (CLP). At 5 hours after CLP, a bolus intravenous injection of 2 nmol ghrelin was followed by a continuous infusion of 12 nmol ghrelin via a primed 200-microL Alzet mini-pump for 15 hours. At 20 hours after CLP, plasma and peritoneal fluid levels of TNF-alpha and IL-6 were determined. The direct effect of ghrelin on cytokine production was studied using cultured normal rat Kupffer cells or peritoneal macrophages stimulated by lipopolysaccharide (LPS). In additional animals, vagotomy or sham vagotomy was performed in sham and septic animals immediately prior to ghrelin administration and cytokine levels were then measured. RESULTS: Ghrelin significantly reduced TNF-alpha and IL-6 levels in sepsis. In contrast, ghrelin did not inhibit TNF-alpha and IL-6 release from LPS-stimulated Kupffer cells or peritoneal macrophages. However, vagotomy, but not sham vagotomy, prevented ghrelin's down-regulatory effect on TNF-alpha and IL-6 production. CONCLUSIONS: Ghrelin down-regulates proinflammatory cytokines in sepsis through activation of the vagus nerve. Pharmacologic stimulation of the vagus nerve may offer a novel approach of anti-sepsis therapy.  相似文献   
999.
育精阴对雄性豚鼠免疫性不育的实验研究   总被引:7,自引:0,他引:7  
目的 研究中药育精阴治疗免疫性不育的作用及其机理。方法 运用主动免疫法造成豚鼠实验性变态反应性睾丸炎 (EAO)模型 ,观察睾丸生精细胞和附睾尾部精子质量的变化。运用不同剂量育精阴灌胃 ,观察育精阴对生精上皮和附睾尾部精子质量的作用。结果 发现实验性变态反应性睾丸炎造成睾丸生精细胞退行性病变 ,附睾精子质量下降。育精阴可减轻和修复实验性变态反应对睾丸附睾的损伤 ,提高附睾精子质量。结论 育精阴对实验性变态反应性睾丸炎造成的免疫损伤有修复作用  相似文献   
1000.
微创技术在腹腔镜胆囊切除术后黄疸诊治中的应用   总被引:5,自引:2,他引:5  
目的:探讨微创技术在腹腔镜胆囊切除术(LC)后黄疸的诊断与治疗中的作用。方法:在微创观念指导下,对LC术后出现黄疸的患者运用内镜逆行胰胆管造影(ERCP)和内镜括约肌切开(EST)等微创技术进行诊断与治疗。结果:我院1998年8月至2001年5月间共行3160例LC手术,术后出现黄疸者5例,均先接受B超、ERCP检查,提示胆总管结石与胆总管末端狭窄,3例EST取石一次成功,1例首次EST取石失败后予保守治疗5天后再行ERCP与碎石治疗成功,1例因结石较多较大行开腹胆总管探查术。结论:对LC术后黄疸,在B超等检查排除明显胆道损伤和胆漏后,胆总管结石应首先考虑。ERCP可进一步明确诊断,EST取石或碎石这一微创技术治疗胆道细小结石伴有胆总管末端炎性狭窄引起的梗阻效果良好。  相似文献   
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