Tissue-Penetrating Ultrasound-Triggered Hydrogel for Promoting Microvascular Network Reconstruction.

The microvascular network plays an important role in providing nutrients to the injured tissue and exchanging various metabolites. However, how to achieve efficient penetration of the injured tissue is an important bottleneck restricting the reconstruction of microvascular network. Herein, the hydrogel precursor solution can efficiently penetrate the damaged tissue area, and ultrasound triggers the release of thrombin from liposomes in the solution to hydrolyze fibrinogen, forming a fibrin solid hydrogel network in situ with calcium ions and transglutaminase as catalysts, effectively solving the penetration impedance bottleneck of damaged tissues and ultimately significantly promoting the formation of microvascular networks within tissues. First, the fibrinogen complex solution is effectively permeated into the injured tissue. Second, ultrasound triggered the release of calcium ions and thrombin, activates transglutaminase, and hydrolyzes fibrinogen. Third, fibrin monomers are catalyzed to form fibrin hydrogels in situ in the damaged tissue area. In vitro studies have shown that the fibrinogen complex solution effectively penetrated the artificial bone tissue within 15 s after ultrasonic triggering, and formed a hydrogel after continuous triggering for 30 s. Overall, this innovative strategy effectively solved the problem of penetration resistance of ultrasound-triggered hydrogels in the injured tissues, and finally activates in situ microvascular networks regeneration.

Human umbilical cord mesenchymal stem cell-derived exosomes promote microcirculation in aged diabetic mice by TGF-ß1 signaling pathway.

BACKGROUND: Microvascular dysfunction is one of the most common pathological characteristics in Type 2 diabetes. Human mesenchymal stem cell-derived exosomes (hUCMSCs-Exo) have diverse functions in improving microcirculation; however, the molecular mechanism of hUCMSCs-Exo in regulating burn-induced inflammation is not well understood. METHODS: hUCMSCs-Exo were extracted by hypervelocity centrifugation method, and exosome morphology was observed by transmission electron microscopy, exosome diameter distribution was detected by particle size analysis, and exosome specific proteins were identified by Western blot.2. DB/DB mice were randomly divided into exosomes group and PBS group. Exosomes and PBS were injected into the tail vein, respectively, and the calf muscle tissue was taken 28 days later. 0.5% Evans blue fluorescence assessment microvascular permeability. The expression of CD31 was detected by immunofluorescence.The morphology and function of microvessels in muscle tissue of lower limbs was evaluated by transmission electron microscopy.3. TMT proteomics was used to detect the changes of differential protein expression in lower limb muscle tissues of the PBS group and the exosome group, and data analysis was performed to screen key signal molecules and their involved biological pathways. Key signal molecules CD105 were verified by Western blot. The expression of TGF-ß1 in exosomes were evaluated by Western blot. RESULTS: Electron microscopy showed that hUCMSCs-Exo presented a uniform vesicle structure, and NTA showed that its diameter was about 160 nm. Western blot showed positive expression of specific proteins CD9, CD81 and TSG101 on exosomes.2. There is no significant change in blood glucose and body weight before and after the exosome treatment. The exosome group can significantly reduce the exudation of Evans blue. Compared with the PBS group. Meanwhile, CD31 immunofluorescence showed that the red fluorescence of exosome treatment was significantly increased, which was higher than that of PBS group. Transmission electron microscopy showed smooth capillary lumen and smooth and complete surface of endothelial cells in the exosome group, while narrow capillary lumen and fingerlike protrusion of endothelial cells in the PBS group.3.Quantitative analysis of TMT proteomics showed that there were 82 differential proteins, including 49 down-regulated proteins and 33 up-regulated proteins. Go enrichment analysis showed that the differential proteins were involved in molecular function, biological process, cell components,among which CD105 was one of the up-regulated proteins. Through literature search, CD105 was found to be related to endothelial cell proliferation. Therefore, this study verified the changes of CD105 in the exosome group, and it was used as the mechanism study of this study. 4. Western blot analysis showed that the expression of CD105 protein in lower limb muscle tissue of exosome group was significantly increased compared with that of PBS group. Based on the fact that CD105 is a component of the TGF-ß1 receptor complex and exosomes are rich in growth factors and cytokines, this study further examined the expression of TGF-ß1 in exosomes, and the results showed that exosomes had high expression of TGF-ß1. CONCLUSION: By improving the integrity of microvascular endothelial cells, hUCMSCs-Exo can improve the permeability of microvessels in diabetic lower muscle tissue, further promote the proliferation of lower limb muscle cells and inhibit the apoptosis of tissue cells. The mechanism may be associated with exosomes rich in TGF-ß1, which is likely to promote endothelial cell proliferation and improve permeability through binding to the endothelial CD105/TßR-II receptor complex, while promoting angiogenesis and protecting skeletal muscle cells from apoptosis.

Intestinal epithelial pH-sensing receptor GPR65 maintains mucosal homeostasis via regulating antimicrobial defense and restrains gut inflammation in inflammatory bowel disease.

Intestinal epithelial cell (IEC) regulation of barrier function and mucosal homeostasis enables the establishment of a harmonious gut microenvironment. However, host-derived regulatory networks that modulate intestinal antimicrobial defenses have not been fully defined. Herein we generated mice with IEC-specific deletion of Gpr65 (Gpr65ΔIEC) and investigated the role of epithelial GPR65 using DSS- and C. rodentium-induced murine colitis models. RNA sequencing analysis was conducted on colonic IECs from Gpr65fl/fl and Gpr65ΔIEC mice, and colonoids and colonic epithelial cell lines were used to evaluate the pH-sensing effect of GPR65. The expression of GPR65 was determined in IECs from patients with inflammatory bowel disease (IBD) and DSS colitis mice by qRT-PCR, Western blot, and immunohistochemistry, respectively. We observed that the absence of GPR65 in IECs abrogated homeostatic antimicrobial programs, including the production of antimicrobial peptides (AMPs) and defense response-associated proteins. Gpr65ΔIEC mice displayed dysbiosis of the gut microbiota and were prone to DSS- and C. rodentium-induced colitis, as characterized by significantly disrupted epithelial antimicrobial responses, pathogen invasion, and increased inflammatory infiltrates in the inflamed colon. RNA sequencing analysis revealed that deletion of GPR65 in IECs provoked dramatic transcriptome changes with respect to the downregulation of immune and defense responses to bacteria. Forced AMP induction assays conducted in vivo or in ex vivo colonoids revealed that IEC-intrinsic GPR65 signaling drove antimicrobial defense. Mechanistically, GPR65 signaling promoted STAT3 phosphorylation to optimize mucosal defense responses. Epithelial cell line and colonoid assays further confirmed that epithelial GPR65 sensing pH synergized with IL-22 to facilitate antimicrobial responses. Finally, the expression of GPR65 was markedly decreased in the inflamed epithelia of IBD patients and DSS colitis mice. Our findings define an important role of epithelial GPR65 in regulating intestinal homeostasis and mucosal inflammation and point toward a potential therapeutic approach by targeting GPR65 in the treatment of IBD.

Medical Data Classification Assisted by Machine Learning Strategy.

With the development of science and technology, data plays an increasingly important role in our daily life. Therefore, much attention has been paid to the field of data mining. Data classification is the premise of data mining, and how well the data is classified directly affects the performance of subsequent models. In particular, in the medical field, data classification can help accurately determine the location of patients' lesions and reduce the workload of doctors in the treatment process. However, medical data has the characteristics of high noise, strong correlation, and high data dimension, which brings great challenges to the traditional classification model. Therefore, it is very important to design an advanced model to improve the effect of medical data classification. In this context, this paper first introduces the structure and characteristics of the convolutional neural network (CNN) model and then demonstrates its unique advantages in medical data processing, especially in data classification. Secondly, we design a new kind of medical data classification model based on the CNN model. Finally, the simulation results show that the proposed method achieves higher classification accuracy with faster model convergence speed and the lower training error when compared with conventional machine leaning methods, which has demonstrated the effectiveness of the new method in respect to medical data classification.

Cyclosporine modulates neutrophil functions via the SIRT6-HIF-1α-glycolysis axis to alleviate severe ulcerative colitis.

BACKGROUND: Cyclosporine A (CsA) is routinely used to treat patients with steroid-refractory acute severe ulcerative colitis (ASUC). Here, we studied the underlying mechanisms of CsA-mediated alleviation in ASUC patients. METHODS: Neutrophil functions including expression of cytokines, apoptosis, and migration were measured by qRT-PCR, flow cytometry, and Transwell assay. Dynamic changes of glycolysis and tricarboxylic acid (TCA) cycle were measured by a Seahorse extracellular flux analyzer. Gene differences were determined and verified by RNA sequencing, qRT-PCR, and Western blotting. Small interfering RNA and inhibitors were used to knock down Sirtuin 6 (SIRT6) in HL-60 cells and block expression of SIRT6, hypoxia-inducible factor-1α (HIF-1α), and pyruvate dehydrogenase lipoamide kinase isozyme 4 (PDK4) in neutrophils. RESULTS: We found that HIF-1α expression and glycolysis significantly increased, while the release of IL-8, myeloperoxidase (MPO) and reactive oxygen species (ROS), the apoptosis, and ability of migration markedly decreased in neutrophils of ASUC patients who responded to CsA (Response group) compared with those who did not respond to CsA (Nonresponse group). We also observed that CsA-induced functional alternation of neutrophils was initiated through suppressing SIRT6 expression, which is responsible for expression of the downstream signaling molecules (e.g., HIF-1α, PFKFB3) and PDK4 ubiquitination, leading to fueling neutrophil glycolysis and TCA cycle. Furthermore, blockage of SIRT6 signaling demonstrated to be the same functional changes as CsA to decrease the migration of neutrophils. CONCLUSIONS: The data reveal a novel mechanism of CsA in alleviating ASUC by promoting neutrophil HIF-1α expression and restricting excessive neutrophil activation in a SIRT6-HIF-1α-glycolysis axis, suggesting SIRT6 as a candidate target for maintaining mucosal homeostasis and treating intestinal inflammation.

Transcatheter Arterial Infusion of Autologous CD133(+) Cells for Diabetic Peripheral Artery Disease.

Microvascular lesion in diabetic peripheral arterial disease (PAD) still cannot be resolved by current surgical and interventional technique. Endothelial cells have the therapeutic potential to cure microvascular lesion. To evaluate the efficacy and immune-regulatory impact of intra-arterial infusion of autologous CD133(+) cells, we recruited 53 patients with diabetic PAD (27 of CD133(+) group and 26 of control group). CD133(+) cells enriched from patients' PB-MNCs were reinfused intra-arterially. The ulcer healing followed up till 18 months was 100% (3/3) in CD133(+) group and 60% (3/5) in control group. The amputation rate was 0 (0/27) in CD133(+) group and 11.54% (3/26) in control group. Compared with the control group, TcPO2 and ABI showed obvious improvement at 18 months and significant increasing VEGF and decreasing IL-6 level in the CD133(+) group within 4 weeks. A reducing trend of proangiogenesis and anti-inflammatory regulation function at 4 weeks after the cells infusion was also found. These results indicated that autologous CD133(+) cell treatment can effectively improve the perfusion of morbid limb and exert proangiogenesis and anti-inflammatory immune-regulatory impacts by paracrine on tissue microenvironment. The CD133(+) progenitor cell therapy may be repeated at a fixed interval according to cell life span and immune-regulatory function.

Tripterine treatment improves endothelial progenitor cell function via integrin-linked kinase.

BACKGROUND/AIMS: Atherosclerosis is associated with dysfunction of endothelial progenitor cells (EPCs). Tripterine, a chemical compound derived from the Chinese medicinal plant Tripterygium wilfordii Hook, displays anti-inflammatory properties in several animal models. We hypothesized that tripterine can improve EPC function and thus the efficiency of EPC transplantation. METHODS AND RESULTS: Tripterine preconditioning (2.5 µM, 4 h) improved EPC proliferation, tube formation, migration, and adhesion, and reduced apoptosis in cells cultured in ox-LDL (200 µg/ml). Tripterine restored integrin-linked kinase (ILK) levels downregulated by ox-LDL in EPCs, suggesting the involvement of the ILK/Akt pathway. Small interfering RNA-mediated depletion of ILK and dominant-negative ILK transduction inhibited the phosphorylation of the ILK downstream signaling targets protein kinase B/Akt and glycogen synthase kinase 3-beta (GSK-3ß), and reduced ß-catenin and cyclin D1 expression. In atherosclerotic mice injected with green fluorescent protein-labeled EPCs to evaluate EPC function, tripterine decreased aortic lesions and plaque deposition, and injection of tripterine-treated EPCs restored ILK levels. CONCLUSION: The present results suggest that tripterine improves vascular function in atherosclerosis by enhancing EPC function through a mechanism involving the ILK signaling pathway.

MiR-21 suppresses endothelial progenitor cell proliferation by activating the TGFß signaling pathway via downregulation of WWP1.

Endothelial damage is strongly associated with cardiovascular diseases such as atherosclerosis. Bone marrow-derived endothelial progenitor cells (EPCs) play an important role in the maintenance of endothelial homeostasis and contribute to re-endothelialization of injured vessels as well as revascularization of ischemic tissues. MicroRNAs (miRNAs) have been reported to regulate EPC biological functions. In this study, we found that EPCs of atherosclerosis patients and EPCs exposed to hypoxia have increased expression of miRNA-21 (miR-21) as well as diminished ability to proliferate. MiR-21 knockdown rescued hypoxia-induced growth arrest in EPCs. Next, we used a luciferase reporter assay to demonstrate that miR-21 downregulates the expression of WW domain-containing protein 1 (WWP1), a negative regulator of TGFß signaling, by directly targeting the 3'-UTR of WWP1. Finally, miR-21 overexpression or WWP1 knockdown in EPCs significantly activates the TGFß signaling pathway and inhibits cell proliferation. Taken together, our results indicate that miR-21 suppresses EPC proliferation by activating the TGFß signaling pathway via downregulation of WWP1. These findings may help the development of strategies to enhance the vitality of EPCs for therapeutic applications.

A dysregulated microRNA-26a/EphA2 axis impairs endothelial progenitor cell function via the p38 MAPK/VEGF pathway.

BACKGROUND: Dysfunction of circulating endothelial progenitor cells (EPCs) is associated with the onset of cardiovascular disorders. Circulating microRNAs (miRNAs) have been recognized as novel biomarkers and potential therapeutic targets. Here, we examined the role of miR-26a overexpression in atherosclerosis and explored the underlying mechanisms. METHODS: EPCs were obtained from patients with atherosclerosis and healthy controls. Bone marrow (BM)-derived EPCs were exposed to hypoxia to mimic the atherosclerotic environment and miR-26a, EphA2 and p38 MAPK levels were measured by qRT-PCR and western blotting, and VEGF levels were determined by enzyme linked immunosorbent assay. Cell viability was assessed using the MTT assay, and luciferase activity assays confirmed EphA2 as a target of miR-26a. RESULTS: MiR-26a was overexpressed in patients with atherosclerosis and associated with EPC dysfunction. EphA2 was identified as a direct target of miR-26a. Overexpression of miR-26a downregulated EphA2 and impaired EPC function, whereas knockdown of miR-26a upregulated EphA2 and reversed hypoxia-induced EPC dysfunction. MiR-26a overexpression or knockdown modulated the activity of p38 MAPK and the levels of VEGF in EPCs. CONCLUSIONS: The role of miR-26a in atherosclerosis is mediated by its target EphA2 via a mechanism involving the p38 MAPK/VEGF pathway.

Genotype-Guided Dosing of Coumarin Anticoagulants: A Meta-analysis of Randomized Controlled Trials.

BACKGROUND: Coumarin anticoagulants (acenocoumarol, phenprocoumon, and warfarin) are generally used for the prevention of stroke in patients with atrial fibrillation or for the therapy and prevention of venous thromboembolism. However, the safe use of coumarin anticoagulants is restricted by a narrow therapeutic window and large interindividual dosing variations. Some studies found that the effectiveness and safety of coumarin anticoagulants therapy were increased by pharmacogenetic-guided dosing algorithms, while others found no significant effect of genotype-guided therapy. METHODS: Four electronic databases were searched from January 1, 2000, to March 1, 2014, for randomized controlled trials of patients who received coumarin anticoagulants according to genotype-guided dosing algorithms. The primary outcome was the percentage of time that the international normalized ratio (INR) was within the normal range (2.0-3.0). Secondary outcomes included major bleeding events, thromboembolic events, and INR ≥4 events. RESULTS: Eight studies satisfied the inclusion and exclusion criteria. Genotype-guided dosing of coumarin anticoagulants improved the percentage of time within the therapeutic INR range (95% confidence interval [CI], 0.02-0.28; P = .02; I(2) = 70%). Subgroup analysis was performed after dividing the nongenotype-guided group into a standard-dose group (95% CI, 0.14-0.49; P = .0004; I(2) = 50%) and a clinical variables-guided dosing algorithm group (95% CI, -0.07-0.15; P = .48; I(2) = 34%). There is a statistically significant reduction in numbers of secondary outcomes (INR ≥4 events, major bleeding events, and thromboembolic events; 95% CI, 0.79-1.00; P = .04). Subgroup analysis of secondary outcomes showed no significant difference between genotype-guided dosing and clinical variables-guided dosing (95% CI, 0.84-1.10; P = .57; I(2) = 11%), but genotype-guided dosing reduced secondary outcomes compared with standard dosing (95% CI, 0.62-0.92; P = .006; I(2) = 0%). CONCLUSIONS: This meta-analysis showed that genotype-guided dosing increased the effectiveness and safety of coumarin therapy compared with standard dosing but did not have advantages compared with clinical variables-guided dosing.

Short time tripterine treatment enhances endothelial progenitor cell function via heat shock protein 32.

The dysfunction of endothelial progenitor cells (EPCs) limits their potential for the treatment of ischemia and atherosclerosis. Therefore, we investigated the effect of tripterine on EPC function and examined the underlying mechanisms. The effect of tripterine, an active component of Tripterygium wilfordii Hook, on the enhancement of EPC function and the efficiency of EPC transplantation was investigated in vitro and in vivo. Treatment of EPCs with tripterine at 2.5 µM for 4 h inhibited oxidized low-density lipoprotein (ox-LDL) induced ROS production, cell apoptosis, and cell senescence and improved the migration and tube formation capacities of EPCs treated with ox-LDL (200 µg/ml). In vivo studies showed that tripterine conditioning of EPCs administered to ischemic foci improved blood perfusion and microvascular density in a mouse hindlimb ischemia model. Examination of the underlying mechanisms indicated that the effect of tripterine is mediated by the induction of heat shock protein 32 expression and the inhibition of JNK activation. The present results are of clinical significance because they suggest the potential of tripterine as a therapeutic agent to improve the efficacy of EPC transplantation for the treatment of ischemic diseases.

Upregulated miR-155 in papillary thyroid carcinoma promotes tumor growth by targeting APC and activating Wnt/ß-catenin signaling.

CONTEXT: MicroRNAs (miRNAs) are strongly implicated in many cancers, including papillary thyroid carcinoma (PTC), which is the most common malignancy in thyroid tissue. Recently, miRNA-155 (miR-155) has been proved to play a substantial role in liposarcoma and breast cancer, but its functions in the context of PTC remain unknown. OBJECTIVES: The objective was to investigate the potential involvement of miR-155 in PTC. DESIGN: Expression levels of miR-155 were assessed via quantitative real-time PCR in 20 pairs of human PTC and adjacent normal tissues and in 4 human PTC cell lines. Lentiviral miR-155 overexpression models were performed in TPC-1 and CGTH-W3 cells, and the effects on cell growth were evaluated. We have searched for miR-155 targets and identified the hypothesis that miR-155 could promote tumor growth of PTC by targeted regulation of adenomatous polyposis coli (APC) expression and activating the Wnt/ß-catenin signaling. RESULTS: MiR-155 levels were markedly increased in PTC specimens and PTC cell lines. Overexpression of miR-155 dramatically promoted PTC cell viability and colony formation in vitro, whereas miR-155 depletion reduced these parameters. Further studies revealed that APC is a novel miR-155 target, because miR-155 bound directly to its 3'-untranslated region and reduced both the mRNA and protein levels of APC. Similar to the miR-155 over-expression, APC downregulation promoted cell growth, whereas rescued APC expression reversed the promotive effect of miR-155. Furthermore, miR-155 overexpression resulted in activation of ß-catenin and induction of several downstream genes including c-Myc, cyclin D1, TCF-1. and LEF-1. Depletion of ß-catenin partially prevented miR-155-induced tumor cell viability and colony formation. In xenograft animal experiments, we found overexpressed miR-155 effectively promoted tumor growth of PTC cells. CONCLUSIONS: Our results indicate that miR-155 functions as an oncogene in PTC. By targeting APC, miR-155 efficiently regulates the Wnt/ß-catenin signaling. And miR-155 may be a potential therapeutic or diagnostic/prognostic target for treating PTC.

Inhibition of Rho and Rac geranylgeranylation by atorvastatin is critical for preservation of endothelial junction integrity.

BACKGROUND: Small GTPases (guanosine triphosphate, GTP) are involved in many critical cellular processes, including inflammation, proliferation, and migration. GTP loading and isoprenylation are two important post-translational modifications of small GTPases, and are critical for their normal function. In this study, we investigated the role of post-translational modifications of small GTPases in regulating endothelial cell inflammatory responses and junctional integrity. METHODS AND RESULTS: Confluent human umbilical vein endothelial cell (HUVECs ) treated with atorvastatin demonstrated significantly decreased lipopolysaccharide (LPS)-mediated IL-6 and IL-8 generation. The inhibitory effect of atorvastatin (Atorva) was attenuated by co-treatment with 100 µM mevalonate (MVA) or 10 µM geranylgeranyl pyrophosphate (GGPP), but not by 10 µM farnesyl pyrophosphate (FPP). Atorvastatin treatment of HUVECs produced a time-dependent increase in GTP loading of all Rho GTPases, and induced the translocation of small Rho GTPases from the cellular membrane to the cytosol, which was reversed by 100 µM MVA and 10 µM GGPP, but not by 10 µM FPP. Atorvastatin significantly attenuated thrombin-induced HUVECs permeability, increased VE-cadherin targeting to cell junctions, and preserved junction integrity. These effects were partially reversed by GGPP but not by FPP, indicating that geranylgeranylation of small GTPases plays a major role in regulating endothelial junction integrity. Silencing of small GTPases showed that Rho and Rac, but not Cdc42, play central role in HUVECs junction integrity. CONCLUSIONS: In conclusion, our studies show that post-translational modification of small GTPases plays a vital role in regulating endothelial inflammatory response and endothelial junction integrity. Atorvastatin increased GTP loading and inhibited isoprenylation of small GTPases, accompanied by reduced inflammatory response and preserved cellular junction integrity.

Computed tomography manifestations of common inferior vena cava dysplasia and its clinical significance.

This study aimed to review and analyse the computed tomography (CT) imaging results of frequently encountered developmental anomalies of the inferior vena cava (IVC). The underlying clinical significance was evaluated with reference to the relevant literature. CT images of patients who received abdominal or thoracic scanning between July 2009 and September 2011 were reviewed. Developmental anomalies observed in the IVC were identified and categorised. Images of the cases with typical anomalies were presented and their developmental mechanism, as well as clinical significance, was discussed. The most frequently encountered IVC developmental anomalies include the left vena cava, double vena cava, azygos continuation of the IVC, left circumaortic renal vein, left retroaortic renal vein and retrocaval ureter. The embryogenesis of the IVC is a complex process that results in various congenital anomalies. The developmental anomalies of the IVC are distinguished using a CT scan and have significant implications on clinical perspective.

Prognosis of patients with gastric cancer and solitary lymph node metastasis.

AIM: To investigate the relationship of solitary lymph node metastasis (SLNM) and age with patient survival in gastric cancer (GC). METHODS: The medical records databases of China's Beijing Cancer Hospital at the Peking University School of Oncology and Shanghai Tenth People's Hospital affiliated to Tongji University were searched retrospectively to identify patients with histologically proven GC and SLNM who underwent surgical resection between October 2003 and December 2012. Patients with distant metastasis or gastric stump carcinoma following resection for benign disease were excluded from the analysis. In total, 936 patients with GC + SLNM were selected for analysis and the recorded parameters of clinicopathological disease and follow-up (range: 13-2925 d) were collected. The Kaplan-Meier method was used to stratify patients by age (≤ 50 years-old, n = 198; 50-64 years-old, n = 321; ≥ 65 years-old, n = 446) and by metastatic lymph node ratio [MLR < 0.04 (1/25), n = 180; 0.04-0.06 (1/25-1/15), n = 687; ≥ 0.06 (1/15), n = 98] for 5-year survival analysis. The significance of intergroup differences between the survival curves was assessed by a log-rank test. RESULTS: The 5-year survival rate of the entire GC + SLNM patient population was 49.9%. Stratification analysis showed significant differences in survival time (post-operative days) according to age: ≤ 50 years-old: 950.7 ± 79.0 vs 50-64 years-old: 1697.8 ± 65.9 vs ≥ 65 years-old: 1996.2 ± 57.6, all P < 0.05. In addition, younger age (≤ 50 years-old) correlated significantly with mean survival time (r = 0.367, P < 0.001). Stratification analysis also indicated an inverse relationship between increasing MLR and shorter survival time: < 0.04: 52.8% and 0.04-0.06: 51.1% vs ≥ 0.06: 40.5%, P < 0.05. The patients with the shortest survival times and rates were younger and had a high MLR (≥ 0.06): ≤ 50 years-old: 496.4 ± 133.0 and 0.0% vs 50-65 years-old: 1180.9 ± 201.8 and 21.4% vs ≥ 65 years-old: 1538.4 ± 72.4 and 37.3%, all P < 0.05. The same significant trend in shorter survival times and rates for younger patients was seen with the mid-range MLR group (0.04-0.06), but the difference between the two older groups was not significant. No significant differences were found between the age groups of patients with MLR < 0.04. Assessment of clinicopathological parameters identified age group, Borrmann type, histological type and tumor depth as the most important predictors of the survival rates and times observed for this study population. CONCLUSION: GC patients below 51 years of age with MLR of SLNM above 0.06 have shorter life expectancy than their older counterparts.

Short-hairpin RNA-mediated Heat shock protein 90 gene silencing inhibits human breast cancer cell growth in vitro and in vivo.

Hsp90 interacts with proteins that mediate signaling pathways involved in the regulation of essential processes such as proliferation, cell cycle control, angiogenesis and apoptosis. Hsp90 inhibition is therefore an attractive strategy for blocking abnormal pathways that are crucial for cancer cell growth. In the present study, the role of Hsp90 in human breast cancer MCF-7 cells was examined by stably silencing Hsp90 gene expression with an Hsp90-silencing vector (Hsp90-shRNA). RT-PCR and Western blot analyses showed that Hsp90-shRNA specifically and markedly down-regulated Hsp90 mRNA and protein expression. NF-kB and Akt protein levels were down-regulated in Hsp90-shRNA transfected cells, indicating that Hsp90 knockout caused a reduction of survival factors and induced apoptosis. Treatment with Hsp90-shRNA significantly increased apoptotic cell death and caused cell cycle arrest in the G1/S phase in MCF-7 cells, as shown by flow cytometry. Silencing of Hsp90 also reduced cell viability, as determined by MTT assay. In vivo experiments showed that MCF-7 cells stably transfected with Hsp90-shRNA grew slowly in nude mice as compared with control groups. In summary, the Hsp90-shRNA specifically silenced the Hsp90 gene, and inhibited MCF-7 cell growth in vitro and in vivo. Possible molecular mechanisms underlying the effects of Hsp90-shRNA include the degradation of Hsp90 breast cancer-related client proteins, the inhibition of survival signals and the upregulation of apoptotic pathways. shRNA-mediated interference may have potential therapeutic utility in human breast cancer.

Emergency endovascular repair of complicated Stanford type B aortic dissections within 24 hours of symptom onset in 30 cases.

OBJECTIVE: To investigate the results of emergency endovascular repair of complicated Stanford type B aortic dissections within 24 hours of symptom onset. METHODS: A retrospective analysis of the clinical data of 30 patients with complicated Stanford type B aortic dissections who underwent emergency endovascular repair between June 2007 and October 2008. Endovascular repairs were performed within 24 hours of symptom onset. Stent-grafts were deployed at the first entry tear through the femoral artery under fluoroscopic guidance. Follow-up computed tomography scans were performed at 1, 3, 6, 12, and 18 months after treatment. RESULTS: The mean patient age was 64 years (range, 43-83 years). There were 3 cases associated with rupture, 6 cases associated with refractory hypertension, 15 cases associated with persistent pain, 2 cases associated with retrograde dissection, and 4 cases associated with malperfusion. The technical success rate was 100%, and the incidence of immediate postoperative endoleaks was 13.4%. One patient died of dissection rupture within 30 days. The mean follow-up period was 12 ± 8 months. A small, persistent endoleak (<10%) occurred in 1 patient, and 1 patient died of acute liver failure 2 months after the operation. No stent dislocation, false lumen expansion, or paraplegia occurred. The false lumen was completely thrombosed in 6 patients and partially thrombosed in 19 patients. The mortality rate was 6.67%. CONCLUSIONS: Our results suggest that emergency endovascular repair of complicated Stanford type B aortic dissections within 24 hours of symptom onset is associated with good outcomes and can decrease mortality.

[Effect of overexpression of glycosylphosphatidylinositol-specific phospholipase D on biological character of hepatocellular carcinoma cell line HepG2].

OBJECTIVE: To investigate the effect of overexpression of glycosylphosphatidyl-inositol-specific phospholipase D (GPI-PLD) on the biological character of hepatocellular carcinoma cell line HepG2. METHODS: The GPI-PLD gene eukaryon expression vector pcDNA3.1(+)/ GPI-PLD was transiently transfected into HepG2 cell by lipid-media transfection. The untransfected HepG2 and HepG2 transfected with pcDNA3.1(+) were used as controls. After screening with G418, the single clone was obtained. The expression level of GPI-PLD mRNA in HepG2 was identified by reverse transcription polymerase chain reaction (RT-PCR). GPI-PLD activities were analyzed quantitatively by triton-X-114 partition with GPI anchored placental alkaline phosphatase (PLAP) as a substrate. Cell count was used to detect the proliferation of the 3 groups, and complement dependent cytotoxicity (CDC) effects were observed by the staining of trypan blue. Apoptosis cells were analyzed by flow cytometry. Carcinoembryonic antigen (CEA)was detected by enzyme linked immunosorbent assay (ELISA). RESULTS: Compared with HepG2 and pcDNA3.1(+)/HepG2 cell, the levels of GPI-PLD activities and its mRNA from pcDNA3.1(+)/GPI-PLD/HepG2 were increased with almost 2 to 5 times,respectively. The GPI anchored PLAP and CEA released into the medium by GPI-PLD, and the rate of CDC killing on the cells were significantly increased. However, the proliferative capacity was obviously decreased, and the typical apoptosis cells were presented in positive clones and its apoptosis rates were increased significantly. CONCLUSION: The stable cell line with overexpression of GPI-PLD has been constructed. The overexpression of GPI-PLD in these cells increases the sensitivity of these cells to CDC killing and impairs the proliferative capacity of cells, and promotes the apoptosis.