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991.

Background

DNA hypermethylation plays important roles in carcinogenesis by silencing key genes. This study aims to identify pivotal genes in hepatocellular carcinoma (HCC) by DNA methylation microarray and to assess their prognostic values.

Materials and Methods

DNA methylation microarray was performed in 45 pairs of HCC and adjacent nontumorous tissues and six normal liver tissues to identify hypermethylated genes in HCC. Potential prognosis-related genes were selected among hypermethylated genes by analyzing influences of methylation levels on disease-free survival (DFS) and overall survival (OS) in 45 patients. Their prognostic values were validated in 154 patients with HCC (including the initial 45 patients) to determine the independent prognostic gene.

Results

Altogether, 54 CpG islands in 44 genes were hypermethylated in HCC compared with liver tissues. Among them, methylation levels of ERG and HOXA11 were inversely associated with DFS (both P < 0.050), and methylation levels of EYA4 were inversely related to DFS and OS (both P < 0.050). EYA4 expression was inversely related to tumor size (P < 0.050). Lower EYA4 expression and larger tumor size were independent predictors of both shorter DFS and OS, and higher Barcelona Clinic Liver Cancer (BCLC) staging was an independent predictor of shorter OS (all P < 0.050).

Conclusions

EYA4 functions as a prognostic molecular marker in HCC. Its aberrant hypermethylation and subsequent down-regulation may promote tumor progression.  相似文献   
992.
The natural history of lamivudine-resistant hepatitis B virus (HBV) infection in renal transplant recipients (RTx) is unclear, despite its increasing incidence. Twenty-nine HBsAg-positive RTx with rising HBV DNA received lamivudine therapy. The course of lamivudine-resistant HBV infection was studied prospectively. During 68.7 +/- 12.5 months of follow-up, 14 (48.3%) patients developed lamivudine resistance, at 10-35 months (mean 16.9 +/- 7.0). All showed mutant sequences at codons 552 and 528 of the YMDD motif, while 13 patients demonstrated wild-type sequence at codon 555. Lamivudine resistance was unrelated to patient demographics, HBeAg status/sero-conversion, or genotype. Following resistance, HBV DNA and alanine aminotransferase showed an initial increase followed by spontaneous gradual reduction. The subsequent peak HBV DNA was lower (1.26 +/- 1.09 x 10(9) vs. 6.26 +/- 12.23 x 10(9) copies/mL, p = 0.011), while that of alanine aminotransferase was higher (196 +/- 117 vs. 77 +/- 47 imicro/l, p = 0.005), compared with pretreatment levels. Post-resistance hepatitic flare occurred in 11 (78.6%) patients. This was transient in four (36.4%), but became chronic in six (54.5%) patients. Decompensation was noted in one patient during this flare, but all survived. We conclude that drug resistance is prevalent in lamivudine-treated RTx. Despite a lower ensuing peak viremia compared with baseline, hepatitic flare is common. While most patients have spontaneous resolution, a minority may develop potentially fatal decompensation during the preceding exacerbation.  相似文献   
993.
Retrievable Inferior Vena Cava Filters: Initial Clinical Results   总被引:9,自引:0,他引:9  
Anticoagulation is the accepted therapy for patients with thromboembolic disease. When contraindications to anticoagulant therapy are present, however, interruption of the inferior vena cava (IVC) may prevent pulmonary embolism (PE). The objective of this study was to report our early technical and clinical results with retrievable IVC filters (IVCFs) for the prevention of PE. One hundred and twenty-seven multitrauma patients between December 1, 2002, and December 31, 2004, underwent placement of Gunther-Tulip (n = 49), Recovery (n = 41), or OptEase (n = 37) retrievable IVCFs under real-time intravascular ultrasound (IVUS) guidance. All patients had abdominal X-rays to verify filter location. Prior to IVCF retrieval, all patients underwent femoral vein color flow ultrasonography to rule out deep vein thrombosis (DVT) and vena-cavography to assess the IVCF for trapped emboli, filter tilt, or retrained thrombus. Thirty-nine patients died of their injuries; no deaths were related to IVCF placement. One PE occurred during follow-up after filter retrieval, and two femoral vein insertion-site DVTs occurred. One hundred twenty (94.4%) of IVCFs were placed without complication at the L2-3 level, as verified by abdominal X-rays. Filter-related complications included three groin hematomas (2.9%) and three IVCFs misplaced in the right iliac vein early in our experience (2.3%); these filters were uneventfully retrieved and replaced in the IVC within 24 hr. Sixty-six patients underwent uneventful retrieval of IVCFs after DVT or PE anticoagulation prophylaxis was initiated. Forty-five IVCFs were not removed: 41 due to contraindications due to anticoagulation and four because of trapped thrombus within the filter. The role of retrievable IVCFs continues to evolve, but in this study of 127 patients, prophylactic temporary IVCF placement was simple and safe, prevented fatal PE, and served as an effective “bridge” to anticoagulation. Further investigation of this bedside IVUS technique and the role of temporary IVCFs in different patient populations is warranted. SECTION EDITOR: Samuel S. Ahn, MD  相似文献   
994.
BACKGROUND: Cell culture experiments show that peritoneal mesothelial cells express aquaporin-1 (AQP1) and aquaporin-3 (AQP3), which can be important for peritoneal transport. However, the functional relevance of aquaporin in mesothelial cells remains uncertain because endothelial cells are generally regarded as the major barrier of peritoneal transport. METHODS: We studied 74 prevalent peritoneal dialysis (PD) patients. Peritoneal permeability was determined by the standard peritoneal equilibration test (PET). Messenger RNA (mRNA) was extracted from the peritoneal dialysis effluent (PDE) after PET, and the aquaporin gene expression was determined by quantitative polymerase chain reaction (PCR). RESULTS: AQP3 mRNA expression in PDE correlated closely with peritoneal transport characteristics, including dialysate-to-plasma creatinine (Cr) ratio at 4 hr (D/P4) (r=0.42, p=0.007), mass transfer area coefficient (MTAC) of Cr (r=0.60, p<0.0001), and net ultrafiltration (UF) (r=0.34, p=0.03). On the other hand, AQP1 mRNA expression did not correlate with D/P4 (r=0.21, p=0.2), MTAC of Cr (r=0.05, p=0.7), or with net UF (r=0.17, p=0.3). There was a modest correlation between AQP3 and connective tissue growth factor (CTGF) mRNA expression in PDE (r=0.30, p=0.06), while AQP1 expression correlated closely with CTGF expression (r=0.56, p=0.0002) and vascular endothelial growth factor (VEGF) expression (r=0.37, p=0.02). AQP3 expression was unaffected by dialysis duration or peritonitis history. The expression of neither AQP1 nor AQP3 correlated with that of transforming growth factor. CONCLUSIONS: Since mesothelial cells are the major source of aquaporin mRNA found in PDE, our findings support a functional role for mesothelial AQP3 in peritoneal transport. Our findings also suggest that AQP3 expression in vivo is regulated by mechanisms other than glucose exposure, peritonitis and traditional growth factors.  相似文献   
995.
Effective design of photocatalysts is an effective method to improve the separation of photogenerated carriers, which improves the photocatalytic performance of photocatalysts. In this work, CoCu-ZIF materials with bimetallic structure were synthesized at room temperature for efficient photocatalytic fuel denitrification. The properties and structures of CoCu-ZIF photocatalysts can be effectively controlled by adjusting the molar ratio of cobalt to copper. The as-prepared CoCu-ZIF photocatalysts were characterized by XRD, FT-IR, SEM, TEM, UV-vis, Raman, BET and other techniques. The photoactivity of CoCu-ZIF for the denitrogenation of NCCs has been evaluated using visible light (λ ≥ 420 nm). The results indicate that Co8Cu2-ZIF photocatalysts exhibit excellent photocatalytic properties, in which the denitrification rate almost reached 80% after 4 hours under visible light irradiation, which is higher than the degradation ability of ZIF-67 (38%). Transient photoelectrochemical experiments and EIS Nyquist plots indicate that Co8Cu2-ZIF with unique structure efficiently improves the separation and transfer of photogenerated electron–hole pairs. Moreover, a possible reaction mechanism was proposed by LC-MS analysis.

Effective design of photocatalysts is an effective method to improve the separation of photogenerated carriers, which improves the photocatalytic performance of photocatalysts.  相似文献   
996.
Cutaneous damage is one of the characterized manifestations in chronic graft‐versus‐host disease (cGVHD). When local effective immunity in the skin is altered to a dysimmune reaction, cutaneous injuries occur. Toll‐like receptor 4 signaling is regarded as a central mediator of inflammation and organ injury. In this study, we found that TLR4 mRNA in peripheral blood from patients with cutaneous cGVHD was markedly increased compared with that from non‐GVHD patients and healthy controls. In addition, NF‐κB expression, TLR4 downstream signaling, and TLR4‐mediated cytokines, including IL‐6 and ICAM‐1, were upregulated. Moreover, ICAM‐1 was widely distributed in skin biopsies from patients with cutaneous cGVHD. We also found that LPS induced TLR4‐mediated NF‐κB activation and IL‐6 and ICAM‐1 secretion in human fibroblasts in vitro. Thus, TLR4, NF‐κB, IL‐6, and ICAM‐1 contribute to the inflammatory response that occurs in cutaneous cGVHD, indicating the TLR4 pathway may be a novel target for cutaneous cGVHD therapy.  相似文献   
997.
Methods for the treatment of tuberculous spondylitis still are controversial. The authors treated 32 consecutive patients with a two-stage surgical technique combined with antituberculous chemotherapy for 1 year. After anterior debridement, fusion with autogenous anterior iliac tricortical strut bone graft was done, and in a second stage, posterior instrumentation and fusion with autogenous posterior iliac corticocancellous bone graft was done 11 days (range, 4-22 days) later. Postoperatively, patients were encouraged to ambulate with brace protection as early as possible. Twenty-nine patients were followed up for a minimum of 2 years (median, 4.7 years; range, 2-10 years) of whom 28 patients achieved solid fusion (97%). All patients had improvement of back pain including the only patient with pseudarthrosis. Neurologic deficits completely recovered in 84% (16 of 19) of patients after 3 months. Kyphotic deformity improved in all 29 patients (34.6 degrees versus 17.3 degrees ) with the average correction angle of 17.3 degrees. Clinically, 27 patients had achieved a satisfactory outcome (93%). There were no evident surgical complications. The authors, therefore, recommend a two-stage surgical technique combined with antituberculous chemotherapy to treat patients with severe vertebral body destruction attributable to tuberculosis because of its high success rate and a low complication rate.  相似文献   
998.
内置式下颌骨牵引成骨术及其常见并发症的处理   总被引:4,自引:12,他引:4  
目的 探讨内置式下颌骨牵引成骨术的常见术后并发症发生的原因及防治措施。方法 总结分析1997至2004年采用内置式下颌骨牵引成骨术治疗下颌骨畸形或缺损患者46例61侧,其中半侧颜面短小27例,下颌骨发育不足或小颌畸形双侧8例、单侧4例,电击伤或肿瘤术后缺损畸形3例,Treaeher Colins综合征2例,睡眠呼吸暂停综合征2例。结果 46例61侧发生并发症者9例,包括牵引机械装置故障3例,局部感染2例,前牙开骀2例,皮肤窦道2例。经积极处理后均达到预期治疗目的。结论 减少下颌骨牵引成骨术并发症的关键在于充分理解下颌骨牵引成骨术的机理,熟悉掌握下颌骨及邻近解剖结构,操作规范熟练,充分的术前准备和术后处理尤为重要。  相似文献   
999.
Aim: To review the evidence in using inflow occlusion during liver resection. Other strategies to minimize the untoward effects of inflow occlusion will also be discussed. Methods: Randomized trials evaluating the use of inflow occlusion in hepatectomy and strategies to minimize its associated adverse effects were reviewed in this article. Recent experience showing comparable operative outcomes without the use of portal clamping was also described. Results: Results from randomized trials and meta‐analyses were not conclusive on the benefits of routine inflow occlusion during liver resection. Intermittent inflow occlusion and ischaemic preconditioning had been found to be effective in reducing ischaemic–reperfusion injury to remnant liver. With refined operative techniques and better instruments, routine inflow occlusion in liver resection can now be safely avoided. Conclusion: Vascular inflow occlusion is an important armamentarium during liver resection, but it should not be used indiscriminately. With refined techniques and better instruments, hepatectomy can be performed safely without the need for routine inflow occlusion.  相似文献   
1000.
INTRODUCTION: Our previous randomized clinical trial comparing the laparoscopic medial-to-lateral dissection with the more classic lateral-to-medial approach for resection of rectosigmoid cancer showed that the medial approach reduces the operative time and the postoperative proinflammatory response. Besides the oncologic advantages of an early vessel division and a "no-touch" dissection, we feel that the longer the lateral abdominal wall attachments of the colon are preserved, the better the exposure and the easier the dissection. Encouraged by the above-mentioned positive findings, we therefore further conduct this phase II clinical trial to examine the feasibility and surgical outcomes regarding the utilization of this medial-to-lateral laparoscopic dissection approach for the curative resection of right-sided colon cancer. METHODS: A total of 104 patients (from December 2000 to January, 2005) with advanced right-sided colon cancer (TNM stage II: n = 56; stage III: n = 48) requiring a curative right hemicolectomy were subjected to the laparoscopic medial-to-lateral approach that included initial exploration and ligation of ileocolic, right colic, and middle colic vessels in no-touch isolation fashion, subsequent medial-to-lateral extension of retroperitoneal dissection along Gerota fascia, opening of lesser sac by transection of gastrocolic ligament, and the final mobilization of hepatic flexure and lateral attachments of ascending colon (Fig. 1). This study was approved by the institutional review committee of National Taiwan University Hospital. The surgical details were shown in the video. Postoperatively, adjuvant chemotherapy with Mayo Clinic Regimen was given in patients with stage III diseases. The functional recovery and surgical outcomes were prospectively evaluated. RESULTS: The laparoscopic medial-to-lateral approach for a curative right hemicolectomy can be preformed with acceptable operation time (192.6 +/- 32.8 min, mean +/- standard deviation) and little blood loss (48.4 +/- 14.4 ml) through a small wound (6.0 +/- 0.8 cm). The number of dissected lymph node was 16.0 +/- 2.8. The operative complications represented 5.7% of all cases, including anastomotic leakage in two cases (1.9%) and wound infection in four cases (3.8%). The patients have quick functional recovery, as evaluated by the length of postoperative ileus (60.0 +/- 12.0 h), hospitalization (9.0 +/- 1.5 days) and degree of postoperative pain (4.0 +/- 0.5, visual analogue scale). Besides the expenses covered by the National Bureau of Health Insurance in Taiwan, the patient had to pay an extra-expenses of NT$ 25,000.0 +/- 2,800.0 (1.0 US$ = 32.0 NT$). During the follow-up periods (median: 30 months, range 6-55 months), recurrence of tumor developed in 6 (10.7%) of stage II and 10 (20.8%) of stage III patients, with liver metastasis in six patients, lung metastasis in 4, liver and lung metastasis in 1, intraperitoneal recurrence in 2, bone metastasis in 1, brain metastasis in 1, and port-site recurrence in 1. CONCLUSIONS: By medial-to-lateral dissection method, the laparoscopic right hemicolectomy can be performed with technical efficiency, short convalescence, and acceptable short-term oncologic results. We therefore encourage the use of this approach for patients requiring a curative laparoscopic right hemicolectomy.  相似文献   
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