Three cases of jejunal tumors detected by standard upper gastrointestinal endoscopy: A case series.

BACKGROUND: In patients with obscure gastrointestinal bleeding, re-examination with standard upper endoscopes by experienced physicians will identify culprit lesions in a substantial proportion of patients. A common practice is to insert an adult-sized forward-viewing endoscope into the second part of the duodenum. When the endoscope tip enters after the papilla, which is a marker for the descending part of the duodenum, it is difficult to endoscopically judge how far the duodenum has been traversed beyond the second part. CASE SUMMARY: We experienced three cases of proximal jejunal masses that were diagnosed by standard upper gastrointestinal endoscopy and confirmed with surgery. The patients visited the hospital with a history of melena; during the initial upper gastrointestinal endoscopy and colonoscopy, the bleeding site was not confirmed. Upper gastrointestinal bleeding was suspected; thus, according to guidelines, upper endoscopy was performed again. A hemorrhagic mass was discovered in the small intestine. The lesion of the first patient was thought to be located in the duodenum when considering the general insertion depth of a typical upper gastrointestinal endoscope; however, during surgery, it was confirmed that it was in the jejunum. After the first case, lesions in the second and third patients were detected at the jejunum by inserting the standard upper endoscope as deep as possible. CONCLUSION: The deep insertion of standard endoscopes is useful for the diagnosis of obscure gastrointestinal bleeding.

Effect of Ranitidine Intake on the Risk of Gastric Cancer Development.

Gastric cancer is one of the most prevalent cancers globally, with high mortality, particularly in East Asia. Certain ranitidine products contain potentially carcinogenic N-nitrosodimethylamine. We investigated the potential association between gastric cancer risk and ranitidine intake using a nationwide cohort, extracted from the Korean National Health Insurance Service. In this longitudinal study, we employed a 1:1 propensity score matching according to sociodemographic factors. A total of 40,887 subjects were enrolled, of which 906 developed gastric cancer during the follow-up period. We investigated gastric cancer events during the follow-up period using the survival analysis, log-rank test, and Cox proportional hazards regression models to estimate incidence, survival rate, and hazard ratio. The incidence of gastric cancer was 67,422; 67,470; and 67,444 person-years in the control, other histamine-2 blockers, and ranitidine groups, respectively. Because the adjusted hazard ratio of gastric cancer was 0.98 and 1.01 in the other histamine-2 blockers and ranitidine groups, respectively, we could not calculate the likelihood of gastric cancer development in the ranitidine group. Ranitidine intake did not significantly increase the incidence of gastric cancer. Therefore, the relative risk of gastric cancer may be low in patients taking ranitidine products in South Korea.

Primary and secondary aerosols in small passenger vehicle emissions: Evaluation of engine technology, driving conditions, and regulatory standards.

The characteristics of primary gas/aerosol and secondary aerosol emissions were identified for small passenger vehicles using typical fuel types in South Korea (gasoline, liquefied petroleum gas (LPG), and diesel). The generation of secondary organic aerosol (SOA) was explored using the potential aerosol mass (PAM) oxidation flow reactor. The primary emissions did not vary significantly between fuel types, combustion technologies, or aftertreatment systems, while the amount of NH3 was higher in gasoline and LPG vehicle emissions than that in diesel vehicle emissions. The SOA emission factor was 11.7-66 mg kg-fuel-1 for gasoline vehicles, 2.4-50 mg kg-fuel-1 for non-diesel particulate filter (non-DPF) diesel vehicles (EURO 2-3), 0.4-40 mg kg-fuel-1 for DPF diesel vehicles (EURO 4-6), and 3-11 mg kg-fuel-1 for LPG vehicles (lowest). The carbonaceous aerosols (equivalent black carbon (eBC) + primary organic aerosol + SOA) of diesel vehicles in EURO 4-6 were reduced by up to 95% compared to those in EURO 2-3. The expected SOA yield increased through the hot-condition combustion section of a vehicle, over the SOA range of 0.2-155 µg m-3. These results provide the necessary data to analyze all types of SOA generated by the gas-phase oxidation in vehicle emissions in metropolitan areas.

Clinical Outcomes of Endoscopic Resection for Low-Grade Dysplasia and High-Grade Dysplasia on Gastric Pretreatment Biopsy: Korea ESD Study Group.

BACKGROUND/AIMS: Some cases of gastric low-grade dysplasia (LGD) and high-grade dysplasia (HGD) on forceps biopsy (FB) are diagnosed as gastric cancer (GC) after endoscopic resection (ER). This study aims to evaluate the clinical outcomes of ER for gastric LGD and HGD on pretreatment FB and to identify the factors that predict pathologic upstaging to GC. METHODS: Patients who underwent ER for LGD and HGD on pretreatment FB from March 2005 to February 2018 in 14 hospitals in South Korea were enrolled, and the patients' medical records were reviewed retrospectively. RESULTS: This study included 2,150 cases of LGD and 1,534 cases of HGD diagnosed by pretreatment FB. In total, 589 of 2,150 LGDs (27.4%) were diagnosed as GC after ER. Helicobacter pylori infection, smoking history, tumor location in the lower third of the stomach, tumor size >10 mm, depressed lesion, and ulceration significantly predicted GC. A total of 1,115 out of 1,534 HGDs (72.7%) were diagnosed with GC after ER. Previous history of GC, H. pylori infection, smoking history, tumor location in the lower third of the stomach, tumor size >10 mm, depressed lesion, and ulceration were significantly associated with GC. As the number of risk factors predicting GC increased in both LGD and HGD on pretreatment FB, the rate of upstaging to GC after ER increased. CONCLUSIONS: A substantial proportion of LGDs and HGDs on pretreatment FB were diagnosed as GC after ER. Accurate ER procedures such as endoscopic submucosal dissection should be recommended in cases of LGD and HGD with factors predicting pathologic upstaging to GC.

Characterization of particulate matter from diesel passenger cars tested on chassis dynamometers.

Emission characterization of particle number as well as particle mass from three diesel passenger cars equipped with diesel particulate filter (DPF), diesel oxidation catalyst (DOC) and exhaust gas recirculation (EGR) under the vehicle driving cycles and regulatory cycle. Total particle number emissions (PNEs) decreased gradually during speed-up of vehicle from 17.3 to 97.3km/hr. As the average vehicle speed increases, the size-segregated peak of particle number concentration shifts to smaller size ranges of particles. The correlation analysis with various particulate components such as particle number concentration (PNC), ultrafine particle number concentration (UFPNC) and particulate matter (PM) mass was conducted to compare gaseous compounds (CO, CO2, HC and NOx). The UFPNC and PM were not only emitted highly in Seoul during severe traffic jam conditions, but also have good correlation with hydrocarbons and NOx influencing high potential on secondary aerosol generation. The effect of the dilution temperature on total PNC under the New European Driving Cycle (NEDC), was slightly higher than the dilution ratio. In addition, the nuclei mode (DP: ≤13nm) was confirmed to be more sensitive to the dilution temperature rather than other particle size ranges. Comparison with particle composition between vehicle speed cycles and regulatory cycle showed that sulfate was slightly increased at regulatory cycle, while other components were relatively similar. During cold start test, semivolatile nucleation particles were increased due to effect of cold environment. Research on particle formation dependent on dilution conditions of diesel passenger cars under the NEDC is important to verify impact on vehicular traffic and secondary aerosol formation in Seoul.

Cryptococcal meningitis in a patient with chronic hepatitis C treated with pegylated-interferon and ribavirin.

Various adverse events have been reported during combination therapy with pegylated (PEG)-interferon-α and ribavirin, although opportunistic infections, especially cryptococcal meningitis, are very rare. A 61-year-old woman complained of headaches and a fever during treatment of a chronic hepatitis C virus (HCV) infection. She had been treated for 7 months. Her headaches were refractory to analgesics, and she developed subtle nuchal rigidity. The cerebral spinal fluid (CSF) revealed a white blood cell count of 205/mm(3), 51 mg/dL protein, 35 mg/dL glucose, and negative Cryptococcus antigen. The CSF culture resulted in no growth. Five days later, the CSF was positive for Cryptococcus antigen. We administered amphotericin B and flucytosine, followed by fluconazole. Approximately 2 months later, she was discharged. For the first time, we report a case of cryptococcal meningitis during the treatment of chronic HCV with PEG-interferon-α and ribavirin.

Microanalysis of stomach cancer glycosaminoglycans.

Glycosaminoglycans (GAGS) are anionic, linear, polysaccharides involved in cell signaling. The GAG content, composition and structure of human tissue have been suggested to play a role in cancer and might provide useful diagnostic or prognostic markers. The current study examines 17 stomach tissue biopsy samples taken from normal individuals and from patients with gastric cancers. An ultrasensitive liquid chromatography (LC) - mass spectrometry assay was applied to individual biopsy samples as small 250 µg providing GAG content and disaccharide composition. The results of these analyses show a significant increase in non-sulfated chondroitin/dermatan sulfate concentration in all cancer samples when compared to normal tissues. In addition in advanced gastric cancer, a significant decrease is observed in hyaluronan.

Does the exposure of urine samples to air affect diagnostic tests for urine acidification?

BACKGROUND AND OBJECTIVES: For accurate measurement of pH, urine collection under oil to limit the escape of CO(2) on air exposure is recommended. This study aims to test the hypothesis that urine collection under oil is not necessary in acidic urine in which bicarbonate and CO(2) are minor buffers, because loss of CO(2) would have little effect on its pH. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: One hundred consecutive random urine samples were collected under oil and analyzed for pH, pCO(2), and HCO(3)(-) immediately and after 5 minutes of vigorous shaking in uncovered flasks to allow CO(2) escape. RESULTS: The pH values in 97 unshaken samples ranged from 5.03 to 6.83. With shaking, urine pCO(2) decreased by 76%, whereas urine HCO(3)(-) decreased by 60%. Meanwhile, urine baseline median pH (interquartile range) of 5.84 (5.44-6.25) increased to 5.93 (5.50-6.54) after shaking (ΔpH=0.12 [0.07-0.29], P<0.001). ΔpH with pH≤6.0 was significantly lower than the ΔpH with pH>6.0 (0.08 [0.05-0.12] versus 0.36 [0.23-0.51], P<0.001). Overall, the lower the baseline pH, the smaller the ΔpH. CONCLUSIONS: The calculation of buffer reactions in a hypothetical acidic urine predicted a negligible effect on urine pH on loss of CO(2) by air exposure, which was empirically proven by the experimental study. Therefore, exposure of urine to air does not substantially alter the results of diagnostic tests for urine acidification, and urine collection under oil is not necessary.

An effective instillation method for water-assisted colonoscopy as performed by in-training endoscopists in terms of volume and temperature.

BACKGROUND AND STUDY AIMS: There is general consensus that water instillation helps insert a colonoscope. However, the most effective method for water instillation has not yet been established, especially for endoscopists-in-training. The aim of this study was to determine volume and temperature for effective water instillation colonoscopy. PATIENTS AND METHODS: This is a prospective, randomized, controlled trial that was carried out at a single center, and a total of 207 consecutive subjects who underwent colonoscopic examination for health checkup were included in the study. Water instillation of supplied water was conducted under four different conditions: 100 and 300 ml at room temperature, 300 ml at 30 °C and no use of water instillation. The following parameters were recorded and analyzed: intubation success rate, independent predictors of successful intubation and intubation time to reach the cecum. RESULTS: The intubation success rate was not significantly different between individual groups. Independent predictors of successful intubation were younger age (P = 0.004) and later examined subjects (P = 0.016). The 300-ml warm water instillation during colonoscopy significantly reduced intubation time over the conventional method without water instillation (P = 0.034). CONCLUSIONS: Instillation of 300-ml warm (30 °C) water during colonoscopy can reduce cecal intubation time for in-training endoscopists without improving the intubation success rate.

Flagellin promotes the proliferation of gastric cancer cells via the Toll-like receptor 5.

Signaling of the Toll-like receptor (TLR) is closely associated with tumor development and progression processes including cell proliferation, angiogenesis, metastasis, and immunosuppression. In this study, we examined the expression of TLR5 in gastric cancer cells and its function in cell proliferation. RT-PCR revealed that the TLR5 gene was expressed in all gastric cancer cell lines examined, SNU638, SNU601, SNU216, and AGS. The TLR5 agonist, flagellin, induced IL-8 production and NF-κB activation in the gastric cancer cell lines. In addition, flagellin enhanced the proliferation of all gastric cancer cells examined, whereas LPS did not affect that of SNU638 cells. Blockade of TLR5 using an antibody, restored the proliferation of SNU638 cells enhanced by flagellin, indicating that TLR5 is essential for cell proliferation by flagellin. Flagellin also led to phosphorylation of ERK in SNU638 cells. The ERK inhibitor, PD98059, restored the proliferation ability of SNU638 cells enhanced by flagellin, suggesting that ERK may play an important role in the proliferation of gastric cancer cells. These findings suggest that TLR5 may play an important role in tumor progression of gastric cancer via the regulation of cell proliferation.