Enhancement of preimplantation mouse embryo development with optimized in vitro culture dish via stabilization of medium osmolarity.

Objective: We evaluated the efficacy of the newly developed optimized in vitro culture (OIVC) dish for cultivating preimplantation mouse embryos. This dish minimizes the need for mineral oil and incorporates microwells, providing a stable culture environment and enabling independent monitoring of individual embryos.

Methods: Mouse pronuclear (PN) zygotes and two-cell-stage embryos were collected at 18 and 46 hours after human chorionic gonadotropin injection, respectively.

Effects of dynamic oxygen concentrations on the development of mouse pre- and peri-implantation embryos using a double-channel gas supply incubator system.

Objective: We aimed to evaluate the effects of different oxygen conditions (20% [high O2], 5% [low O2] and 5% decreased to 2% [dynamic O2]) on mouse pre- and peri-implantation development using a novel double-channel gas supply (DCGS) incubator (CNC Biotech Inc.) to alter the oxygen concentration during in vitro culture.

Methods: The high-O2 and low-O2 groups were cultured from the one-cell to the blastocyst stage under 20% and 5% oxygen concentrations, respectively.

Endoscopic hemostasis in nonvariceal upper gastrointestinal bleeding: comparison of physician practice in the East and the West.

Background: Endoscopic hemostasis is commonly practiced during GI endoscopy practice. We hypothesized that, because the choice of endoscopic intervention is influenced by many factors, for example personal experience, prior training, guidelines, etc., there would be differences in practice patterns among different groups of endoscopists.

Managing anticoagulation and antiplatelet medications in GI endoscopy: a survey comparing the East and the West.

Background: Anticoagulation and antiplatelet medications may potentiate GI bleeding, and their use may lead to an increased need for a GI endoscopy. We hypothesized that there might be different practice patterns among international endoscopists.

Objective: To explore the differences in management practices for patients who receive anticoagulation and antiplatelet medications from Eastern and Western endoscopists.

Irritable bowel syndrome is more common in women regardless of the menstrual phase: a Rome II-based survey.

Functional gastrointestinal disorders are more common in women in relation to the fluctuations of female sex hormones. We tried to know the gender-related differences in the prevalence of irritable bowel syndrome and gastrointestinal symptoms according to the menstrual phase. A total of 253 women before menopause and 252 men below age 50 were examined by a gastroenterologist after completing the questionnaire.

Link between a preference for women colonoscopists and social status in Korean women.

Background: Although the sex preference in women patients for their colonoscopist has been reported, the characteristics of these women have not been evaluated yet.

Objective: The aim of this study was to investigate the characteristics of women who have a specific preference for a man or a woman colonoscopist.

Design: Single-center prospective study.

Decreasing prevalence of Helicobacter pylori infection: a 9-year observational study.

Background/aims: Detailed information is still lacking on the trends of changes in Helicobacter pylori infection. The aim of the study was to investigate how the prevalence of H. pylori infection varied with gender and age during the past 9 years.

Sonic hedgehog expression in gastric cancer and gastric adenoma.

Hedgehog protein is essential to gastrointestinal tract development, and disruption of the hedgehog signaling pathway is associated with gastrointestinal tumorigenesis. Here, we analyzed the degree of hedgehog expression in gastric cancer and precancerous tissue. From August 2005 to May 2006, 52 gastric cancers and 16 gastric adenomas were obtained from surgically or endoscopically resected specimens.

In vitro differentiation of germ cells from nonobstructive azoospermic patients using three-dimensional culture in a collagen gel matrix.

Objective: To assess the effectiveness of the three-dimensional culture of spermatogenic cells in a collagen gel matrix from nonobstructive azoospermic patients and examine the relation between the success rate of in vitro spermatogenesis and serum FSH level as a diagnostic prediction.

Design: Prospective study using radioimmunoassay, immunocytochemistry, and flow cytometry with primary cultured cells.

Setting: Gynecologic clinics and human reproduction research laboratory.

Epidemiology of HIV/AIDS among Asians and Pacific Islanders in the United States.

Although the percentage of overall AIDS diagnoses remains low among Asian and Pacific Islanders (APIs) in the United States compared with other racial/ethnic groups, research on API risk behaviors and health status suggest that the low number of AIDS cases may not provide a full picture of the epidemic and issues faced by this understudied and underserved population. Data from national HIV/AIDS surveillance systems and the Behavioral Risk Factor Surveillance System (BRFSS) were examined to delineate the magnitude and course of the HIV/AIDS epidemic among APIs in the United States. Same-sex sexual activity is the main HIV risk for API men, whereas heterosexual contact is for API women.

Recalling sexual partners: the accuracy of self-reports.

Accuracy of recall of the number of sexual partners individuals had over a period of one month, three months, six months and one year was studied in a group of 285 young, single, heterosexual adults. Self-reports of the number of partners were obtained on a weekly basis and then compared with recall of behavior over longer time periods that overlapped the weekly measures. For individuals who claimed abstinence or who claimed to be monogamous, accuracy of recall was relatively high, especially at the shorter time frames.

Clinical usefulness of carbohydrate antigen 19-9 as a screening test for pancreatic cancer in an asymptomatic population.

Background And Aim: Although the prognosis for pancreatic cancer is generally poor, it is well known that the survival rate for resected pancreatic cancer is much higher than that for more conservative treatment. The importance of early detection is emphasized for resection of pancreatic cancer. Measurement of serum carbohydrate antigen (CA) 19-9 has shown satisfactory sensitivity and predictive value in symptomatic patients, but no available data has been found on healthy asymptomatic subjects.

[The clinical usefulness of SPIO-MRI in detection and staging of hepatocellular carcinoma].

Background/aims: It is still unclear whether Super Paramagnetic Iron Oxide-Magnetic Resonance Imaging (SPIO-MRI) is a clinically useful imaging modality for patients with hepatocellular carcinoma (HCC). This study searched for the clinical usefulness and limitations of SPIO-MRI with respect to tumor detection capacity, false positive and negative rate, and early recurrence rate.

Methods: From December 1999 to February 2001, 218 patients who were surgical candidates by 3-phase dynamic helical CT (3dHCT) were enrolled.

TT virus infection in patients on maintenance hemodialysis in Korea.

Background/aims: TT virus is a novel DNA virus that is associated with posttransfusion hepatitis. The prevalence, risk factors, and clinical significance of TT virus infection were evaluated in patients with chronic renal failure who are on hemodialysis.

Methodology: Nested polymerase chain reaction was used to test for TT virus DNA in the serum of patients on hemodialysis as well as in healthy controls.

[Prospective randomized trial of intravenous ciprofloxacin for prevention of bacterial infection in cirrhotic patients with esophageal variceal bleeding].

Background/aims: In cirrhotic patients with esophageal variceal bleeding, bacterial infections are a frequent complication. Oral antibiotic prophylaxis decreases the incidence of bacterial infections. The administration of oral antibiotics, however, may be difficult in some cirrhotic patients with active bleeding.

Role of TGF-beta 1 and TGF-beta type II receptor in gastric cancer.

Background: TGF-beta is known as a cell growth inhibitory factor to suppress almost all cells, including the epithelial cell. Unlike normal cells, cancer cells are not affected by TGF-beta growth inhibitory action and the lack of TGF-beta receptor expression or mutation is being reported as its mechanism, which is rarely studied in Korea. Therefore, we investigated this study to clarify the role of TGF-beta I and TGF-beta II receptors in gastric cancer.

Apoptosis and its correlation with proliferative activity in rectal cancer.

Background And Objectives: Alterations in the normal control of apoptosis and cell proliferation are important factors in multistep colorectal carcinogenesis. The aim of this study was to determine the frequency of apoptosis and cell proliferation in rectal cancers and to examine their relationship to clinicopathological variables and expression of bcl-2 and p53.

Methods: Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) staining and immunohistochemical staining for Ki-67, bcl-2, and p53 were performed on paraffin-embedded tissue samples of 57 rectal cancers.

Clinical diagnosis of primary epiploic appendagitis: differentiation from acute diverticulitis.

Background: Primary epiploic appendagitis (PEA) is an uncommon cause of abdominal pain that occurs either from appendageal torsion or spontaneous thrombosis of an appendageal draining vein. Primary epiploic appendagitis is frequently misdiagnosed as either appendicitis or diverticulitis, depending on its location.

Study: Clinical and radiologic characteristics of 8 patients with PEA were retrospectively reviewed and compared with 18 patients with acute diverticulitis.