Cytokine and immunoglobulin production by PWM-stimulated peripheral and tumor-infiltrating lymphocytes of undifferentiated nasopharyngeal carcinoma (NPC) patients

BACKGROUND: Undifferentiated Nasopharyngeal Carcinoma (NPC) patients show a characteristic pattern of antibody responses to the Epstein-Barr virus (EBV) which is regularly associated with this tumor. However, no EBV-specific cytotoxic activity is detectable by the standard chromium-release assay at both peripheral and intratumoral levels. The mechanisms underlying this discrepancy between the humoral and cellular immune responses in NPC are still unknown, but might be related to an imbalance in immunoregulatory interleukin production. In this report, we investigated the ability of peripheral (PBL) and tumor- infiltrating (TIL) lymphocytes of undifferentiated NPC patients to produce in vitro three interleukins (IL-2, IL-6, IL-10) and three immunoglobulin isotypes (IgM, IgG, IgA). METHODS: Lymphocytes from 17 patients and 17 controls were cultured in the presence of Pokeweed mitogen (PWM) for 12 days and their culture supernatants were tested for interleukins and immunoglobulins by specific enzyme-linked immunosorbent assays (ELISA). Data were analysed using Student's t-test and probability values below 5% were considered significant. RESULTS: The data obtained indicated that TIL of NPC patients produced significantly more IL-2 (p = 0,0002), IL-10 (p = 0,020), IgM (p= 0,0003) and IgG (p < 0,0001) than their PBL. On the other hand, patients PBL produced significantly higher levels of IL-2 (p = 0,022), IL-10 (p = 0,016) and IgM (p = 0,004) than those of controls. No significant differences for IL-6 and IgA were observed. CONCLUSION: Taken together, our data reinforce the possibility of an imbalance in immunoregulatory interleukin production in NPC patients. An increased ability to produce cytokines such as IL-10 may underlie the discrepancy between humoral and cellular immune responses characteristic of NPC

Оптимізація електричних характеристик діода Шотткі Au/n-InN/InP на основі контактної техніки різних діаметрів

Оптимізація електричних характеристик електронних компонентів є основною метою більшості сучасних досліджень у цій галузі. У роботі проведено експериментальне дослідження діода Шотткі. Дослідження базується на застосуванні нового підходу вимірювання, який використовує контактний метод Шотткі при металізації золота. Досліджувана структура складається з підкладки InP обраного перерізу (1 см × 1 см), товщиною порядка 350 мкм, вирізаною в кристалографічній площині (100). На цій підкладці вигравіруваний тонкий шар InN (2 нм). Ми використовували золото для двох різних значень діаметрів, розміщених один біля іншого довільним чином; великий ( = 1,366038 мм) і малий ( = 0,815575 мм). Наша методика вимірювання дозволила отримати такі електричні характеристики діода Шотткі як I-V, C-V і G-V. Вимірювання дозволили обчислити коефіцієнт ідеальності ( 1,79, 2,58), струм насичення, потенційний бар'єр ( = 0,66 еВ, еВ) і послідовний опір ( Ω, Ω) для двох різних діаметрів. Результати вимірювань, отримані на нашому діоді InN/InP Au/n типу, показують оптимізовані електричні характеристики досліджуваного діода Шотткі. Ми порівняли отримані результати для кожного контакту з результатами інших нещодавніх робіт у тієї ж галузі досліджень. Порівняння показало гарне узгодження з точки зору числових значень, а також ефективності запропонованого нами методу вимірювання.Optimization of electrical characteristics for electronic components is a main objective for the majority of recent research in this field. In this work, an experimental study of the Schottky diode is realized. This study is based on the proposal of a new measurement approach which concerns the Schottky contact technique by metallization of gold. The structure studied is composed of the InP substrate of selected section (1cm × 1cm), thickness of the order of 350 μm and cut out in the crystallographic plane (100). On this substrate, a thin layer of InN (2 nm) is engraved. We have used gold (Au) for two different values of diameters placed one next to the other in an alternative way; large ( dL = 1.366038 mm) and small ( = 0.815575 mm). Our measurement technique has allowed us to obtain the electrical characteristics of the Schottky diode I-V, C-V and G-V. These measurements allowed us to calculate the ideality factor ( 1.79, 2.58), the saturation current ( IsL = 6.717x10-4mA, Issm = 6.84x10-4mA), the potential barrier (ФBL = 0.66 eV, ФBsm = 0.64 eV) and the series resistance (RsL = 271Ω, Rssm = 261Ω) of our diode for the two diameters. The measurement results obtained on our Au/n-type InN/InP diode show the optimized electrical characteristics of the studied Schottky diode. In the logic of comparison of our work, we compared the obtained results for each contact and also the important results of other recent works for the same field of research. This comparison showed us a good agreement from the point of view of numerical values as well as the effectiveness of our proposed measurement approach

Use of sedation for routine diagnostic upper gastrointestinal endoscopy: a European Society of Gastrointestinal Endoscopy Survey of National Endoscopy Society Members.

Sedation rates may vary among countries, depending on patients' and endoscopists' preferences. The aim of this survey was to investigate the rate of using premedication for routine diagnostic upper gastrointestinal (UGI) endoscopy in endoscopy societies, members of the European Society of Gastrointestinal Endoscopy (ESGE). We evaluated a multiple-choice questionnaire which was e-mailed to representatives of national endoscopy societies, which are members of the ESGE. The questionnaire had 14 items referring to endoscopy practices in each country and the representatives' endoscopy units. The response rate was 76% (34/45). In 47% of the countries, less than 25% of patients undergo routine diagnostic UGI endoscopy with conscious sedation. In 62% of the responders' endoscopy units, patients are not asked their preference for sedation and do not sign a consent form (59%). Common sedatives in use are midazolam (82%), diazepam (38%) or propofol (47%). Monitoring equipment is not available 'in most of the endoscopy units' in 46% (13/28) of the countries. Though they were available in 91% of the national representatives' endoscopy units, they are rarely (21%) used to monitor unsedated routine diagnostic UGI endoscopy. In about 50% of ESGE-related countries, less than 25% of patients are sedated for routine diagnostic UGI endoscopy. Major issues to improve include availability of monitoring equipment and the use of a consent form