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1.

Objective

The aim of this study was to elucidate the clinicopathological significance and prognostic role of loss of claudin-1 in colorectal cancer (CRC).

Methods

The correlations between claudin-1 expression and clinicopathological characteristics, including survival rates, were assessed using immunohistochemistry on 260 archival, paraffin-embedded CRC tissues. In addition, the correlations between cludin-1 and nuclear factor-kappa B (NF-κB), epithelial-mesenchymal transition markers and tumor-infiltrating lymphocytes were investigated.

Results

Claudin-1 expression was markedly lost in 42.7% of the 260 CRCs analyzed. Loss of claudin-1 expression significantly correlated with larger tumor size, vascular invasion, higher pT stage, and high metastatic lymph node ratio. In addition, loss of claudin-1 expression significantly correlated with NF-κB activation (P?<?0.001), high SNAI (P?<?0.001), and low E-cadherin (P?<?0.001) expressions. Patients with high immunoscores showed significantly lower rates of claudin-1 expression loss (P?=?0.020). In detail, loss of claudin-1 expression were frequently found in CRCs low CD3- and CD8-positive lymphocytes. There were significant correlations between claudin-1 expression loss and poor overall and recurrence-free survivals (P?<?0.001 and P?<?0.001, respectively).

Conclusion

Taken together, our results suggest that the loss of claudin-1 expression significantly correlates with aggressive tumor behaviors, high SNAI expression, lower immunoscore, and poor prognoses.  相似文献   
2.
Methods for derivation of human embryonic stem cells   总被引:6,自引:0,他引:6  
The expanded blastocysts, developed from 2PN-stage embryos, are generally divided into three categories: a good blastocyst containing a large and distinguishable inner cell mass (ICM), a blastocyst with a small and distinct ICM, and a blastocyst with a poorly defined ICM. In this study, we introduce methods for the derivation of human embryonic stem cells (hESCs) depending on the quality of the blastocysts. An immunosurgical method was used for the good expanded blastocysts. This method, however, raises the probability of ICM loss in cases of hESC derivation from blastocysts with smaller or indistinct ICMs. Furthermore, this method is also associated with a risk of the contamination of the hESCs with animal pathogens. To overcome these shortcomings, the partial- or whole-embryo culture method was used. For blastocysts with no visible ICM, the whole-embryo culture method was used to establish hESCs via the seeding of the entire blastocyst without its zona pellucida directly on a STO feeder layer. However, trophectodermal overgrowth tends to hinder the expansion of the ICM during the initial steps of hESC derivation. Therefore, the partial-embryo culture method was developed to establish hESCs from blastocysts with smaller ICMs. The surgical isolation of the region containing the ICM with an ultra-fine glass pipette alleviates trophectoderm overgrowth. This method is also applicable to blastocysts with large and distinct ICMs, and the efficiency of this method is comparable to that of the immunosurgical method.  相似文献   
3.
While several studies have explored nutrient intake and dietary habits associated with depression, few studies have reflected recent trends and demographic factors. Therefore, we examined how nutrient intake and eating habits are associated with depression, according to gender and age. We performed simple and multiple regressions using nationally representative samples of 10,106 subjects from the Korea National Health and Nutrition Examination Survey. The results indicated that cholesterol, dietary fiber, sodium, frequency of breakfast, lunch, dinner, and eating out were significantly associated with depression (p-value < 0.05). Moreover, depression was associated with nutrient intake and dietary habits by gender and age group: sugar, breakfast, lunch, and eating out frequency in the young women’s group; sodium and lunch frequency among middle-age men; dietary fibers, breakfast, and eating out frequency among middle-age women; energy, moisture, carbohydrate, lunch, and dinner frequency in late middle-age men; breakfast and lunch frequency among late middle-age women; vitamin A, carotene, lunch, and eating out frequency among older age men; and fat, saturated fatty acids, omega-3 fatty acid, omega-6 fatty acid, and eating out frequency among the older age women’s group (p-value < 0.05). This study can be used to establish dietary strategies for depression prevention, considering gender and age.  相似文献   
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Background

Modern ceramic-on-ceramic bearings have become attractive alternatives to conventional polyethylene in total hip arthroplasty (THA) as a result of their low wear and minimal particle production. However, 28-mm heads in ceramic-on-ceramic bearing couples have been associated with ceramic fracture. To address these issues, 32-mm and larger ceramic heads with a titanium-alloy sleeve have been introduced, although limited data are available on their durability and clinical outcomes.

Questions/purposes

We determined (1) the survivorship of the primary ceramic-on-ceramic THA using a 32-mm ceramic head with a titanium-alloy sleeve at a minimum followup of 5 years; (2) Harris hip scores; (3) the incidence of ceramic fracture and noisy hip; and (4) the proportion of hips showing radiographic evidence of osteolysis.

Methods

From November 2005 to August 2009, we performed 301 ceramic-on-ceramic THAs using a 32-mm ceramic head with a titanium-alloy sleeve in 270 patients. Of these, 12 patients (12 hips [4%]) died from problems unrelated to surgery and 13 patients (15 hips [5%]) were lost during followup before a minimum of 5 years had been reached, leaving 245 patients who had 274 THAs with a minimum followup of 5 years (mean, 6.5 years; range, 5–9 years) in this retrospective analysis. During the study period, 30% (301 of 997 hips) were performed with this articulation based on the operating surgeon’s discretion. The mean patient age at the time of surgery was 55 years (range, 16–82 years). All operations were performed at a single center. All of the ceramic implants were hot isostatic-pressed, laser-marked, proof-tested third-generation alumina. We determined the implant survival, Harris hip scores, incidence of ceramic fracture or noisy hips (based on a questionnaire), and presence of osteolysis.

Results

The survival rate of ceramic-on-ceramic bearings in primary THA using a 32-mm ceramic head with a titanium-alloy sleeve was 98% (95% confidence interval, 96%–100%) at 9 years. The Harris hip score improved from a mean of 47 points preoperatively to 93 points at last followup. One ceramic head fractured at 6 years postoperatively. No ceramic liners fractured. Audible hip clicking and squeaking were identified in four hips and one hip, respectively. Osteolysis was detected in three hips, but none had symptoms.

Conclusions

Primary ceramic-on-ceramic THA using a 32-mm ceramic head with a titanium-alloy sleeve has a survivorship of 98% at 9-year followup. Nevertheless, surgeons should be aware of the potential risks of ceramic fracture, noise, and osteolysis associated with the use of a ceramic head with a titanium-alloy sleeve.

Level of Evidence

Level IV, therapeutic study.  相似文献   
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This study aimed to assess vaccination coverage for novel influenza A (H1N1) in Korea using a immunization registry system as the data source. Vaccination coverage was found to be 26.1% for the total population and 54.4% for priority groups targeted by a national vaccination campaign between October 27, 2009, to March 31, 2010. The factors associated with increased coverage were rapid vaccination and free vaccination; these factors may need to be considered in future pandemics.  相似文献   
9.
IL-17 is involved in inducing and mediating pro-inflammatory responses. The association of IL-17 with tumor growth or graft-versus-host disease (GVHD) has become a subject of controversy. We hypothesized that serum IL-17 (sIL-17) levels during the peri-transplant period may affect alloreactive responses after allogeneic stem cell transplantation (SCT). sIL-17 levels of 95 patients with leukemia who had undergone myeloablative allogeneic SCT were measured using ELISA before conditioning and on day?0, +7, and +14 after transplantation. With a median follow-up of 17?months, the overall survival, disease-free survival, non-relapse mortality, and relapse incidence were 70.9%, 66.3%, 10.3%, and 23.4%, respectively. Ten patients relapsed within 180?days (early relapse, 10.5%) post-transplant. The cumulative incidence of acute GVHD over grade II and chronic GVHD was 55.8% and 69.0%, respectively. Analyses using repeated measures of ANOVA and mean values of sIL-17 revealed that patients relapsed within 180?days had higher sIL-17 levels, whereas no association existed between sIL-17 levels and other clinical outcomes, including acute GVHD. Receiver operating characteristic curve analyses also revealed that sIL-17 levels were available for the prediction of early relapse and that patients with higher sIL-17 levels at each time point had a significantly higher early relapse. Multivariate analyses and subgroup analyses with only standard disease status suggest the association of sIL-17 levels with subsequent early relapse independent of disease status at transplantation. This study is the first one demonstrating the early change in sIL-17 during the peri-transplant period and the association with early relapse in humans.  相似文献   
10.
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