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Purpose: To survive in an ischemic microenvironment with a lower extracellular pH, ability to up-regulate proton extrusion is critical for cancer cell survival. Gastric H+/K+-ATPase exchanges luminal K+ for cytoplasmic H+ and is the enzyme primarily responsible for gastric acidification. On the basis of the fact that blocking the clearance of acidic metabolites are known to induce the cell death, we hypothesized that pantoprazole (PPZ), one of gastric H+/K+-ATPase inhibitors used frequently to treat acid-related diseases, could inhibit growth of tumor cells. Experimental Design: Genomic DNA fragmentation, terminal deoxynucleotidyl transferase (Tdt)-mediated nick end labeling assay, and annexin V staining were performed to detect PPZ-induced apoptosis. Mitogen-activated protein kinase activation and heat shock proteins expression were determined by immunoblot with specific antibodies. The antitumor effect of PPZ was evaluated in vivo by a xenograft model of nude mice. Results: After PPZ treatment, apoptotic cell death was seen selectively in cancer cells and was accompanied with extracellular signal-regulated kinase deactivation. By contrast, normal gastric mucosal cells showed the resistance to PPZ-induced apoptosis through the overexpression of antiapoptotic regulators including HSP70 and HSP27. In a xenograft model of nude mice, administration of PPZ significantly inhibited tumorigenesis and induced large-scale apoptosis of tumor cells. Conclusions: PPZ selectively induced in vivo and in vitro apoptotic cell death in gastric cancer, suggesting that proton pump inhibitors could be used for selective anticancer effects.

One WLAN cell results in unintentional interference to the adjacent cells using the channel of which center frequency is insufficiently separated. The interference affects the adjacent cells as partial band jamming (PBJ). This paper presents the effect of partial band jamming on orthogonal frequency division multiplexing (OFDM) systems. PBJ is modeled on the rectangular spectrum with uniformly distributed random phase over [0, 2/spl pi/). An upper bound of bit error probability (BEP) performance based on the effective signal to noise power ratio (SNR) is provided for OFDM systems in Rayleigh fading channels in addition to AWGN. Finally, coding gain over partial band jamming is analyzed in an OFDM-based wireless local area network (WLAN).

Internet marketplaces are now faced with new challenges that arise from the need to seamlessly integrate an enormous number of product catalogs from different sources. In order to help users find products efficiently, Internet shops provide hierarchies of product catalogs (called category hierarchies). However, the absence of robust models (and well understood semantics) for product catalogs and their hierarchies severely impairs our ability to systematically support structured operations. We present an extended catalog model whose purpose is to provide a universal product catalog repository with browsing, searching and downloading capabilities in order to facilitate catalog sharing and interoperability. In addition, we present a model for category hierarchies with well defined semantics which allows flexible representation of product hierarchies as well as automatic merging of different category hierarchies as a special case of catalog integration.

Catalogs are an essential part of online commercial transactions. It is estimated that over 50% of the start-up cost of an average Internet shop is spent in building the digital catalogs that describe the products and services it offers. The manufacturers of the products must send their product information to each and every shop that carries their products. We present the architecture and technical issues of our DCL system. The primary objective of the system is to provide a shared repository of digital product catalogs for Internet shops to reduce the cost of catalog management. The manufacturer will upload the core catalogs that include the basic information about her products. The shop can download these core catalogs and build its own customized catalogs on top of them. The database is designed to accommodate evolving schemas for various product groups. The system also has a flexible categorization hierarchy which is used to define product classification.

Bluetooth systems result in unintentional interference to OFDM systems using industry, science and medical (ISM) bands. The performance degradation of orthogonal frequency division multiplexing (OFDM) systems from Bluetooth interference is analyzed numerically. Bluetooth interference is modeled on partial band jamming with a rectangular spectrum. Bit error probability (BEP) performance based on the effective signal-to-noise power ratio (SNR) is provided for OFDM systems in Rayleigh fading channels in addition to AWGN. Additionally, coding gain over Bluetooth interference is evaluated for an OFDM-based wireless local area network (WLAN) in IEEE 802.11g.

This paper presents an integrated 8-VSB receiver IC which demodulates and decodes the ATSC-compliant terrestrial RF transmission signal. The design has been accomplished in an ASIC-vendor independent way using only HDL description and synthesis tools. It can receive any IF signal of 5.38 MHz or 44 MHz. The chip has been implemented with equivalent 300 k gates comprising 200 k logic parts and 100 k gate-equivalent memory parts in an area of 8.0/spl times/7.7 mm/sup 2/. The chip is operative at 50 MHz and consumes approximately 3.2 W under 5 volts in a commercial operating condition.

With an increasing demand of ethical standard on current business environment, leader's ethical behavior (i.e., ethical leadership) has received a particular attention. Drawing on self-verification...

Learning goal orientation and self-efficacy have a significant impact on employees’ performance, and leader may affect it. Applying trait activation theory, this study focuses on the role of situat...

Limited data are available on severe community-acquired pneumonia (severe CAP or SCAP) caused by Streptococcus pneumoniae in Korea. All patients who were admitted to a tertiary hospital for CAP from January 2007 to December 2008 were reviewed retrospectively, and SCAP was defined by 2007 Infectious Disease Society of America/American Thoracic Society criteria. In total, 94 patients were diagnosed with SCAP (mean age, 73.5 ± 14.3 years; male, 70). Among them, pneumococcal SCAP (P-SCAP) accounted for 24.5%, and non-P-SCAP accounted for 18.1% (four with Pseudomonas aeruginosa, [4.3%]; four with Staphylococcus aureus, [4.3%]), and no organisms were identified in 57.4% of the patients. A history of neoplasm was Less frequent, and the incidence of shock and pneumonia severity index (PSI) scores were Lower in patients with P-SCAP than in those with non-P-SCAP or with SCAP with no organism identified (p = 0.012, 0.023 and 0.007, respectively). Patients with P-SCAP had a Lower rate of treatment failure (p = 0.048) and tended to have Lower in-hospital and 30-day mortalities compared with those with non-P-SCAP. In a multivariate analysis, the history of neoplasm was the strongest independent factor for predicting 30-day mortality (odds ratio, 9.068; 95% confidence interval, 1.856-44.309). SCAP accounted for 24.5% of SCAP cases. P-SCAP was associated with Lower disease severity and a tendency toward better hospital outcomes compared with non-P-SCAP. (Korean J Med 2012;82:52-59)

Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal-dominantly inherited disease that occurs in approximately one in 5000 to 8000 people. Clinical diagnosis of HHT is made when a person presents three of the following four criteria: family history, recurrent nosebleeds, mucocutaneous telangiectasis, and arteriovenous malformations (AVM) in the brain, lung, liver and gastrointestinal (GI) tract. Although epistaxis is the most common presenting symptom, AVMs affecting the lungs, brain and GI tract provoke a more serious outcome. Heterozygous mutations in endoglin, activin receptor-like kinase 1 (ACVRL1; ALK1), and SMAD4, the genes involved in the transforming growth factor-β family signaling cascade, cause HHT. We report here the case of a 63 year-old male patient who presented melena and GI bleeding episodes, proven to be caused by bleeding from multiple gastric angiodysplasia. Esophagogastroduodenoscopy revealed multiple angiodysplasia throughout the stomach. Endoscopic argon plasma coagulation was performed to control bleeding from a gastric angiodysplasia. The patient has been admitted several times with episodes of hemoptysis and hematochezia. One year ago, the patient was hospitalized due to right-sided weakness, which was caused by left basal ganglia hemorrhage as the part of HHT presentation. In family history, the patient’s mother and elder sister had died, due to intracranial hemorrhage, and his eldest son has been suffered from recurrent epistaxis for 20 years. A genetic study revealed a mutation in exon 3 of ALK1 (c.199C > T; p.Arg67Trp) in the proband and his eldest son presenting epistaxis.

Cowden syndrome is a rare autosomal dominant disorder that is characterized by multiple hamartomas in a variety of tissues and this is associated with germline mutations in the phosphatase and tensin homologue (PTEN) gene, which is the tumor suppressor gene located on chromosome 10q23.3. It is characterized by multiple hamartomatous neoplasms of the skin, oral mucosa, gastrointestinal (GI) tract, bones, central nervous system, eyes, and genitourinary tract. Cowden syndrome does not have increased risk of GI malignancy; however, it has an increased risk of breast, thyroid and endometrial cancer development. Here the authors report a rare case of Cowden syndrome incidentally diagnosed from multiple gastric polyposis. A 29-year-old woman presented with multiple gastric polyps. The laboratory results were normal except for mild anemia, with a hemoglobin level of 11.9 g/dL. Esophagogastroduodenoscopy revealed multiple gastric, duodenal polyps and esophageal acanthosis. Colonoscopy revealed possible hamartomatous polyps in the rectum. Under the suspicion of Cowden syndrome, sonography of the thyroid and breasts was carried out, which revealed multiple thyroid masses. Subsequent fine-needle aspiration biopsy revealed the presence of clusters of follicular epithelial cells, and due to the possibility of malignancy, the patient underwent total thyroidectomy. The pathology was reported as invasive follicular carcinoma. A gene study by direct sequencing showed the presence of a PTEN mutation (c.633C > A /p.Cys211*).

Background: Though infections of Helicobacter pylori (H. pylori) are closely associated with activation of host angiogenesis, the underlying mechanisms, as well as the strategy for its prevention, have not been identified. Here, we investigated a causal role of H. pylori infection in angiogenesis of gastric mucosa and a potent inhibitory effect of a gastric proton pump inhibitor (PPI) on the gastropathy. Materials and Methods: A comparative analysis of CD 34 expression in tissues obtained from 20 H. pylori-associated gastritis and 18 H. pylori-negative gastritis patients was performed. Expression of and VEGF were tested by using RT-PCR. To evaluate the direct effect of H. pylori infection on differentiation of endothelial HUVEC cells, we carried out an in vitro angiogenesis assay. Results: H. pyfori-associated gastritis tissues showed significantly higher density of blood vessels than did H. pylori-negative gastritis tissues, and the levels were well correlated with expressions of . Conditioned media from H. pylori-infected gastric mucosal cells stimulated a tubular formation of HUVEC cells. We also found a significant inhibitory effect of PPI, an agent frequently used for H. pylori eradication, on H. pylori-induced angiogenesis. This drug effectively inhibited the phosphorylation of MAP kinase ERK1/2, which is a principal signal for H. pylori-induced angiogenesis. Conclusion: The fact that PPls can down-regulate H. pylori-induced angiogenesis suggest that anti-angiogenic treatment using PPI may be a preventive approach for H. pylori-associated carcinogenesis.