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. These were cultured for 120 hours using potassium simplex optimized medium (KSOM) to reach the blastocyst stage. The embryos were randomly allocated into three groups, each cultured in one of three dishes: a 60-mm culture dish, a microdrop dish, and an OIVC dish that we developed. RESULTS: The OIVC dish effectively maintained the osmolarity of the KSOM culture medium over a 5-day period using only 2 mL of mineral oil. This contrasts with the significant osmolarity increase observed in the 60-mm culture dish. Additionally, the OIVC dish exhibited higher blastulation rates from two-cell embryos (100%) relative to the other dish types. Moreover, blastocysts derived from both PN zygotes and two-cell embryos in the OIVC dish group demonstrated significantly elevated mean cell numbers. CONCLUSION: Use of the OIVC dish markedly increased the number of cells in blastocysts derived from the in vitro culture of preimplantation mouse embryos. The capacity of this dish to maintain medium osmolarity with minimal mineral oil usage represents a breakthrough that may advance embryo culture techniques for various mammals, including human in vitro fertilization and embryo transfer programs.

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. In the dynamic-O2 group, mouse embryos were cultured from the one-cell to the morula stage under 5% O2 for 3 days, followed by culture under 2% O2 to the blastocyst stage. To evaluate peri-implantation development, the blastocysts from the three groups were individually transferred to a fibronectin-coated dish and cultured to the outgrowth stage in droplets. RESULTS: The blastocyst formation rate was significantly higher in the low-O2 and dynamic-O2 groups than in the high-O2 group. The total cell number was significantly higher in the dynamic-O2 group than in the low-O2 and high-O2 groups. Additionally, the apoptotic index was significantly lower in the low-O2 and dynamic-O2 groups than in the high-O2 group. The trophoblast outgrowth rate and spread area were significantly higher in the low-O2 and dynamic-O2 groups than in the high-O2 group. CONCLUSION: Our results showed that a dynamic oxygen concentration (decreasing from 5% to 2%) had beneficial effects on mouse pre- and peri-implantation development. Optimized, dynamic changing of oxygen concentrations using the novel DCGS incubator could improve the developmental competence of in vitro cultured embryos in a human in vitro fertilization and embryo transfer program.

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. OBJECTIVE: To explore the potentially different practices for endoscopic hemostasis between the "East" (eight Asian countries) and the "West" (USA and Canada). DESIGN: Cross-sectional descriptive study (internet-based survey). STUDY SUBJECTS: We administered a questionnaire survey to American Society of Gastrointestinal Endoscopy (ASGE) and Korean Society of Gastroenterology (KSGE) members (see: http://www4.utsouthwestern.edu/inetdemo/endoscopy/hemostasis.html , or supplementary paper for review online). RESULTS: Eastern ASGE members (n = 112) were more likely to complete this survey than ASGE members in the West (n = 180): 15.1 vs. 5.0%, P < 0.001. Choice of hemostatic method, regardless of primary or recurrent bleeding, varied significantly among Eastern and Western endoscopists. For example, for treatment of a gastric ulcer with a visible vessel, a vast majority (70%) of Western endoscopists preferred pre-injection followed by thermocoagulation whereas responses from the East were more diverse, with endoclip application +/- pre-injection being the top choice (29%) (P < 0.001). Personal EGD volume and hospital bed numbers did not seem to be associated with hemostatic choices in either the East or the West. CONCLUSIONS: Endoscopic hemostasis practice patterns for upper GI tract bleeding differed among Eastern and Western endoscopists, suggesting fundamental differences in practice habit determinants.

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. DESIGN: International survey study. SETTING: Academic medical centers and private clinics. SUBJECTS: Members of the American Society for Gastrointestinal Endoscopy (ASGE) in Eastern (Korea, Japan, China, India, Thailand, Singapore, Malaysia, and Philippines) and Western (United States and Canada) countries were invited to complete a Web-site-based questionnaire. In addition, the questionnaire was sent to university hospitals in South Korea and academic institutions in the United States. METHODS: A survey was administered that contained detailed questions about the use of an endoscopy in patients on anticoagulation and antiplatelet medications. MAIN OUTCOME MEASUREMENTS: Different opinions and clinical practice patterns regarding the use of anticoagulation and antiplatelet medications by Eastern and Western endoscopists. RESULTS: A total of 105 Eastern and 106 Western endoscopists completed the survey. Western endoscopists experienced more instances of procedure-related bleeding (P = .003) and thromboembolism after withdrawal of medications (P = .016). Eastern endoscopists restarted medications later (1-3 days) than Western endoscopists after a biopsy (same day) (P < .001). Eastern endoscopists withdrew aspirin for more than 7 days before a polypectomy and then restarted it 1 to 3 days after a polypectomy, whereas Western endoscopists performed a polypectomy without withdrawing aspirin (P < .001). ASGE guidelines were followed less often by Eastern than by Western endoscopists (P < .001). LIMITATIONS: Low response rate, heterogeneity of the sample, and recall bias. CONCLUSIONS: The opinions and clinical practice patterns for the management of anticoagulation and antiplatelet medications differed significantly between Eastern and Western endoscopists. The lack of uniformity in practice patterns suggests that more data and better education are required in the area of GI endoscopy for patients on anticoagulation and antiplatelet medications, particularly given that individual patient characteristics may be associated with unique types of complications.

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. SETTING: Academic medical center, from October to November 2005. SUBJECTS: A total of 465 women who visited the Digestive Disease Center. METHODS: Subjects were asked to complete a self-administered questionnaire on the sex preference of the colonoscopist, employment status, and clinical symptoms. MAIN OUTCOME MEASUREMENTS: Factors related with sex preference for the colonoscopist. RESULTS: Only 358 subjects (77.0%) completed the questionnaire. Of these, 195 women (54.5%) had no preference, whereas 115 women (32.1%) preferred a woman colonoscopist and 48 women (13.4%) preferred a man colonoscopist. Subjects who preferred women colonoscopists were generally younger (P< .0001), more educated (P< .0001), single (P< .0001), and employed (P< .0001) than the other population. Neither the symptoms of functional dyspepsia nor irritable bowel syndrome were related with the sex preference of the colonoscopist. LIMITATIONS: A self-administered questionnaire study did not investigate specific physician interpersonal or communication styles. CONCLUSIONS: More than half of the women had no sex preference for their colonoscopist, and the sex preference for a specific sex was related to employment status, education level, age, and marital status. Such a sex-based preference in employed, highly educated young women predicts an increasing demand for women colonoscopists in the near future, particularly given the increasing social participation of women in these times of rapid industrialization.

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. Blood tests, endoscopic procedures, and imaging studies were done, if needed. Women were subclassified into three groups according to their menstruation period; menstrual phase, proliferative phase, and secretory phase. Finally, 179 men and 193 women were analyzed. Irritable bowel syndrome was more frequently noticed in women than in men (p=0.01). The diarrhea-dominant type was more common in men, while constipation-dominant or alternating types were more common in women (p<0.001). Of 193 women, there was no significant difference in their gastrointestinal symptoms according to their menstrual phase. Regardless of the menstrual phase, gastrointestinal symptoms are more frequent in women. Physicians should consider different symptomatic manifestations between men and women should be considered when evaluating functional gastrointestinal disorders.

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. METHODOLOGY: A total of 8646 subjects who submitted to a rapid urease test were included. The prevalence of H. pylori infection according to age and gender was analyzed. RESULTS: H. pylori infection was noted in 3747 cases (43.3%) of all cases. The infection rate was 50.0% in 1997, but declined gradually down to 40.6% in 2005 (P < 0.001). The rate of H. pylori infection reached a peak at the age of 30-39 years and decreased thereafter in men while it reached a peak at the age of 40-49 years in women (P < 0.001). The prevalence was higher in men than in women before the age 50 years (P < 0.001) while there was no difference after the age 50 years (P = 0.28) in any of the years studied. CONCLUSIONS: H. pylori infection has gradually decreased over the past decade, and there is a gender-related difference in the prevalence of H. pylori infection manifesting as a lower rate of infection in young women and an earlier plateau of infection rate in men.

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. Immunohistochemical staining using sonic hedgehog (Shh) antibody was performed in cancerous and noncancerous tissue portions. Hedgehog expression was assessed based on the summed scores of the intensity and proportion of Shh staining. According to Lauren's classification, Shh expression was stronger in the intestinal type than in the diffuse type (p<0.001). Although Shh expression was not related to the location, size, metastatic status, or mucin phenotype of the gastric cancer, the expression was stronger in the tubular type of gastric cancer than in the mucinous and signet-ring cell types (p=0.001). Shh expression was stronger in gastric adenoma than in the diffuse-type gastric cancer (p<0.001), but revealed no difference with that of the intestinal-type gastric cancer (p=0.30). Shh expression was strongest in all types of intestinal metaplasia of noncancerous tissues. Shh expression is related to the intestinal type of gastric cancer. The stronger Shh expression in intestinal metaplasia and gastric adenoma indicates that hedgehog protein is involved at an early phase of gastric carcinogenesis.

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. PATIENT(S): Primary culture of spermatogenic cells established from 18 nonobstructive azoospermic patients who underwent histologic diagnoses. INTERVENTION(S): Primary culture of spermatogenic cells in a collagen-based gel matrix, subjected to immunological and flow cytometric analyses. MAIN OUTCOME MEASURE(S): In vitro culture of spermatogenic cells was established in an extracellular milieu that more closely resembled the in vivo condition. The number of chromosomes in newly generated cells during culture was determined by fluorescence-activated cell sorter (FACS) and immunocytochemical analysis. Effects of FSH on the differentiation of the spermatogenic cells were measured. RESULT(S): Results of histologic studies indicated that 8 of 18 patients showed the spermatocyte arrest. Immunocytochemical and FACS analysis indicated that after 12 days in culture, haploid cells comprised 11%-37% of the cultured cell population with a characteristic expression of a cellular marker for spermatids. The serum level of FSH appeared to be closely correlated with an increase in the number of haploid cells in culture. CONCLUSION(S): The present three-dimensional culture in a collagen gel matrix provides a suitable means by which spermatocytes could be induced to differentiate into presumptive spermatids in vitro. In addition, the plasma FSH level could be a good indicator for the success of differentiation of cultured spermatogenic cells obtained from patients with spermatogenic arrest.

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. Thus, the authors aimed to determine the clinical usefulness of CA 19-9 as a screening tool for pancreatic cancer in asymptomatic subjects. METHODS: From December 1994 to November 2000, 70 940 asymptomatic persons visiting the Health Promotion Center at the Samsung Medical Center, Seoul, Korea, participated. All subjects underwent abdominal ultrasonography and serum CA 19-9 measurement. The authors analyzed the sensitivity, specificity, and predictive values of CA 19-9 for detecting pancreatic cancer. Also, those subjects who had a serum CA 19-9 level above the cut-off value were followed up using a serial check of CA 19-9, computed tomography, or endoscopic retrograde cholangiopancreatography. RESULTS: The number of subjects with a level of CA 19-9 above the cutoff of 37 U/mL was 1063 (1.5%), including four cases diagnosed with pancreatic cancer. The prevalence of pancreatic cancer over the age of 30 years is 13.66 per 100 000 population in Korea. Therefore, the sensitivity is 100% and the specificity 98.5%. However, the positive predictive value of CA 19-9 for detecting pancreatic cancer is only 0.9% in the asymptomatic population. CONCLUSION: Mass screening for pancreatic cancer using CA 19-9 levels in asymptomatic subjects is ineffective because of a very low positive predictive value, despite its high sensitivity and specificity.

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. RESULTS: TT virus DNA was detected in 15 (20.0%) of the 75 patients on hemodialysis and 10 (13.2%) of the 76 healthy controls (P > 0.05). In chronic renal failure patients on hemodialysis, the prevalence of TT virus did not differ according to the duration of hemodialysis or the amount of blood transfusion. The prevalence of TT virus was higher in IgG anti-hepatitis B core antibody-positive patients than IgG anti-hepatitis B core antibody-negative patients (27.5% vs. 4.2%, P = 0.03). Two (13.3%) of the 15 TT virus-positive and 6 (10.0%) of the 60 TT virus-negative patients showed elevated alanine aminotransferase levels (P > 0.05). CONCLUSIONS: TT virus infection did not occur more frequently in patients on hemodialysis than in healthy controls. No relationship was found between TT virus infection and liver disease. The correlation between TT virus infection and IgG anti-hepatitis B core antibody suggests that TT virus may share some routes of transmission with hepatitis B virus.

[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. The purpose of this study was to assess the efficacy of prophylactic intravenous antibiotics for the prevention of bacterial infections in cirrhotic patients with esophageal variceal bleeding. METHODS: From December 1998 to September 2001, a total of 40 consecutive cirrhotic patients with Child-Pugh class B or C were enrolled after emergent endoscopic esophageal variceal ligation (EVL) was taken because of esophageal variceal bleeding. Enrolled patients were randomized into a treatment group and a control group. The treatment group (n=20) received the intravenous ciprofloxacin 200mg IV q 12 hours for 3 days while the control group(n=20) didn,t. RESULTS: Bacterial infection developed in nine patients (45%) of the control group and only two patients (10%) in the treatment group. The incidence of bacterial infections was significantly lower in the treatment group than the control group (p < 0.005). The hospital cost and length of hospital stay decreased in the treatment group compared with the control group (p < 0.001). There were no differences in the hospital course and mortality within 30 days between the two groups. CONCLUSIONS: In cirrhotic patients with variceal bleeding and with Child-Pugh class B or C, the use of intravenous ciprofloxacin for 3 days after EVL was not only effective in the prevention of bacterial infections but also cost-effective.

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. METHODS: 23 cases that underwent operations for gastric cancer provided RNA collected from their carcinoma tissues and adjacent normal tissues. We investigated the level of TGF-beta 1 and T beta R-II mRNA expression with semi-quantitatively reverse transcription PCR and analyzed the correlation with prognostic factors, such as tumor size, depth of invasion, tumor differentiation and lymph-node metastasis. RESULTS: (1) TGF-beta 1 and T beta R-II mRNA were expressed in all carcinoma tissues and adjacent normal tissues of the 23 cases without statistical difference in the level of the expression. (2) The level of TGF-beta 1 mRNA expression was higher in patients with gastric cancer invaded only at the mucosa and submucosa than in patients with gastric cancer invaded over muscular propria, and also higher in the patients without lymph-node metastasis or perineural invasion than in the patients with lymph-node metastasis or perineural invasion. There was no significant correlation between the level of T beta R-II mRNA expression and several parameters, such as age, gender, tumor size, location, differentiation, Lauren's classification and vascular invasion. (3) There was a significant correlation between the level of TGF-beta 1 and T beta R-II mRNA expression in carcinoma tissues. CONCLUSION: It indicated that TGF-beta 1 mRNA expression in gastric cancer might concern the early stage of gastric carcinogenesis and, unlike the earlier reports, it was higher in patients with early gastric cancer, negative lymph-nodes or negative perineural invasion. Further studies are required to clarify the role of TGF-beta 1 in gastric carcinogenesis with more patients.

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. RESULTS: Patients with PEA presented with lower abdominal pain of recent onset that was localized to the left (seven cases) and right (one case) lower quadrants. Well-localized tenderness without peritoneal irritation sign was usually the only physical finding. Blood tests were not significant. In acute diverticulitis, the pain was more evenly distributed throughout the lower abdomen and findings like nausea, fever, and leukocytosis were more frequently associated than in PEA. Computed tomography findings, such as pedunculated oval fatty mass with streaky densities connected to the serosal surface of the adjacent colon, can lead to the diagnosis of PEA. Symptoms of PEA were resolved within 1 week (mean, 4.7 days) without surgery. CONCLUSIONS: When patients with very localized lower abdominal pain and tenderness do not have associated symptoms or laboratory abnormalities, a high index of suspicion for PEA and early radiologic examinations are required.

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. RESULTS: There was a positive linear correlation between apoptotic index (AI) and proliferative index (PI) (gamma = 0.276, P = 0.038). Both apoptosis and cell proliferation were more frequently found in rectal cancers with lymph node metastasis (P = 0.045 and 0.010, respectively). However, the ratio of AI and PI was not different by nodal status. There was no association between Dukes stage and AI or PI. The frequency of apoptosis was inversely related to the expression of bcl-2, but was not related to the p53 status of rectal cancer. There were no association between cell proliferation and the expression of bcl-2 or p53. CONCLUSIONS: Our results suggest that the susceptibility to apoptosis in rectal cancer is clearly related to the proliferative activity and high turnover rate of tumor cells may contribute to lymph node metastasis.