High-glutathione mesenchymal stem cells isolated using the FreSHtracer probe enhance cartilage regeneration in a rabbit chondral defect model

BACKGROUND

Mesenchymal stem cells (MSCs) are a promising cell source for cartilage regeneration. However, the function of MSC can vary according to cell culture conditions, donor age, and heterogeneity of the MSC population, resulting in unregulated MSC quality control. To overcome these limitations, we previously developed a fluorescent real-time thiol tracer (FreSHtracer) that monitors cellular levels of glutathione (GSH), which are known to be closely associated with stem cell function. In this study, we investigated whether using FreSHtracer could selectively separate high-functioning MSCs based on GSH levels and evaluated the chondrogenic potential of MSCs with high GSH levels to repair cartilage defects in vivo.

METHODS

Flow cytometry was conducted on FreSHtracer-loaded MSCs to select cells according to their GSH levels. To determine the function of FreSHtracer-isolated MSCs, mRNA expression, migration, and CFU assays were conducted. The MSCs underwent chondrogenic differentiation, followed by analysis of chondrogenic-related gene expression. For in vivo assessment, MSCs with different cellular GSH levels or cell culture densities were injected in a rabbit chondral defect model, followed by histological analysis of cartilage-regenerated defect sites.

RESULTS

FreSHtracer successfully isolated MSCs according to GSH levels. MSCs with high cellular GSH levels showed enhanced MSC function, including stem cell marker mRNA expression, migration, CFU, and oxidant resistance. Regardless of the stem cell tissue source, FreSHtracer selectively isolated MSCs with high GSH levels and high functionality. The in vitro chondrogenic potential was the highest in pellets generated by MSCs with high GSH levels, with increased ECM formation and chondrogenic marker expression. Furthermore, the MSCs' function was dependent on cell culture conditions, with relatively higher cell culture densities resulting in higher GSH levels. In vivo, improved cartilage repair was achieved by articular injection of MSCs with high levels of cellular GSH and MSCs cultured under high-density conditions, as confirmed by Collagen type 2 IHC, Safranin-O staining and O'Driscoll scores showing that more hyaline cartilage was formed on the defects.

CONCLUSION

FreSHtracer selectively isolates highly functional MSCs that have enhanced in vitro chondrogenesis and in vivo hyaline cartilage regeneration, which can ultimately overcome the current limitations of MSC therapy.

Suppression of Tobacco Carcinogen-Induced Lung Tumorigenesis by Aerosol-Delivered Glycerol Propoxylate Triacrylate-Spermine Copolymer/Short Hairpin Rab25 RNA Complexes in Female A/J Mice

BACKGROUND

Rab25, a member of Rab family of small guanosine triphosphatase, is associated with progression of various types of human cancers, including lung cancer, the leading cause of cancer-associated deaths around the globe.

METHODS

In this study, we report the gene therapeutic effect of short hairpin Rab25 RNA (shRab25) on 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung tumorigenesis in female A/J mice. Initially, mice (6 weeks old) were injected with single dose of NNK (2 mg/0.1 mL saline/mouse) by intraperitoneal injection to induce the tumor. Eight weeks later, shRab25 was complexed with glycerol propoxylate triacrylate-spermine (GPT-SPE) copolymer and delivered into tobacco-induced lung cancer models through a nose-only inhalation system twice a week for 2 months.

RESULTS

GPT-SPE/shRab25 largely decreased the tobacco-induced tumor numbers and tumor volume in the lungs compared to GPT-SPE- or GPT-SPE/shScr-delivered groups. Remarkably, aerosol-delivered GPT-SPE/shRab25 significantly decreased the expression level of Rab25 and other prominent apoptosis-related proteins in female A/J mice. The apoptosis in these mice was determined by detecting the expression level of Bcl-2, proliferating cell nuclear antigen, Bax, and further confirmed by TUNEL assay.

CONCLUSIONS

Our results strongly confirm the tumorigenic role of Rab25 in tobacco carcinogen-induced lung cancer and hence demonstrate aerosol delivery of shRab25 as a therapeutic target for lung cancer treatment.

Meta-analysis of predictive clinicopathologic factors for lymph node metastasis in patients with early colorectal carcinoma

The objective of this study was to conduct a meta-analysis to determine risk factors that may facilitate patient selection for radical resections or additional resections after a polypectomy. Eligible articles were identified by searches of PUBMED, Cochrane Library and Korean Medical Database using the terms (early colorectal carcinoma [ECC], lymph node metastasis [LNM], colectomy, endoscopic resection). Thirteen cohort studies of 7,066 ECC patients who only underwent radical surgery have been analysed. There was a significant risk of LNM when they had submucosal invasion (≥ SM2 or ≥ 1,000 µm) (odds Ratio [OR], 3.00; 95% confidence interval [CI], 1.36-6.62, P = 0.007). Moreover, it has been found that vascular invasion (OR, 2.70; 95% CI, 1.95-3.74; P < 0.001), lymphatic invasion (OR, 6.91; 95% CI, 5.40-8.85; P < 0.001), poorly differentiated carcinomas (OR, 8.27; 95% CI, 4.67-14.66; P < 0.001) and tumor budding (OR, 4.59; 95% CI, 3.44-6.13; P < 0.001) were significantly associated with LNM. Furthermore, another analysis was carried out on eight cohort studies of 310 patients who underwent additional surgeries after an endoscopic resection. The major factors identified in these studies include lymphovascular invasion on polypectomy specimens (OR, 5.47; 95% CI, 2.46-12.17; P < 0.001) and poorly or moderately differentiated carcinomas (OR, 4.07; 95% CI, 1.08-15.33; P = 0.04). For ECC patients with ≥ SM2 or ≥ 1,000 µm submucosal invasion, vascular invasion, lymphatic invasion, poorly differentiated carcinomas or tumor budding, it is deemed that a more extensive resection accompanied by a lymph node dissection is necessary. Even if the lesion is completely removed by an endoscopic resection, an additional surgical resection should be considered in patients with poorly or moderately differentiated carcinomas or lymphovascular invasion.

[Clinical characteristics and treatment outcome of colonic diverticulitis in young patients]

BACKGROUND/AIMS

The clinical course and the most appropriate management of colonic diverticulitis in young patients are currently unresolved. This retrospective study was designed to compare young patients (≤40 years) with older patients (>40 years) regarding clinical characteristics of acute colonic diverticulitis and to determine whether differences exist in treatment outcome.

METHODS

Three-hundred sixty eight patients presenting with acute colonic diverticulitis from March 2001 through April 2011 at Ewha Womans University Mokdong Hospital were reviewed retrospectively. The differences in clinical characteristics, treatment modality and recurrence between each group were analyzed.

RESULTS

Two-hundred and six patients were aged 40 years or younger and 162 patients were older than 40 years. The older group was diagnosed more frequently with severe diverticulitis. Surgical treatment was significantly more frequent in the older group than in the younger group (15.4% vs. 4.4%, p<0.001). No significant difference was found in preatment modality between the two groups in patients with recurrence. The difference in recurrence between groups was not statistically significant. In multivariate analysis, left colonic diverticulitis was significantly associated with severe diverticulitis (OR, 14.651; 95% CI, 4.829-44.457) and emergency surgery (OR, 13.745; 95% CI, 4.390-43.031).

CONCLUSIONS

When patients with colonic diverticulitis are treated conservatively, young age is no longer an independent risk factor for subsequent poor outcome. Diverticulitis in young patients does not have a particularly aggressive or fulminant course. Therefore, we recommend that diverticulitis management should be based on the severity and location of the disease, and not on the age of the patient.

Gastric schwannoma diagnosed by endoscopic ultrasonography-guided trucut biopsy

Schwannomas of the gastrointestinal (GI) tract are rare subepithelial tumors comprising approximately 3.3% to 12.8% of all mesenchymal tumors of the GI tract. On endoscopic ultrasound (EUS) they are seen as hypoechoic tumors arising most commonly from the 4th proper muscle layer. Although EUS helps to distinguish tumor characteristics, tissue sampling is required for differentiation with other more common tumors such as GI stromal tumors. Both EUS-guided fine needle aspiration and EUS-guided trucut biopsy (EUS-TCB) can be used for tissue sampling. However, only EUS-TCB allows core biopsy and a high yield of immunohistochemical staining. We report a case of a gastric schwannoma diagnosed by EUS-TCB.

Helicobacter pylori eradication on iatrogenic ulcer by endoscopic resection of gastric tumour: a prospective, randomized, placebo-controlled multi-centre trial

INTRODUCTION

The role of Helicobacter pylori (H. pylori) eradication has not been clarified in the healing of iatrogenic ulcer after endoscopic resection of gastric neoplasm. The aim of this study was to evaluate whether H. pylori eradication could facilitate the healing of iatrogenic ulcer after endoscopic resection of gastric neoplasm.

METHODS

A total of 232 patients with H. pylori-positive early gastric cancer or gastric adenoma underwent endoscopic resection and were randomly allocated to eradication or placebo group in a prospective, double-blinded, and placebo-controlled manner. The primary outcome was measured by healing rate of ulcer, and the secondary outcomes by reduction rate of ulcer size, relief rate from ulcer-related symptoms, and adverse event rates.

RESULTS

The healing rate of ulcer was 53% in eradication group and 51.6% in placebo group, respectively (p value=0.95). The reduction rate of ulcer size, relief rate from ulcer-related symptoms and adverse event rates were also not different between two groups. In multivariate analysis, initial ulcer size more than 3 cm and histology of cancer were significant factors affecting iatrogenic ulcer healing.

CONCLUSIONS

H. pylori eradication did not facilitate iatrogenic ulcer healing at early and late phase after endoscopic resection of gastric neoplasm.

Endoscopic resection of hypopharyngeal squamous cell carcinoma

Hypopharyngeal cancers are often diagnosed at an advanced stage and have a poor prognosis. Even when they are diagnosed at an operable stage, surgery often results in substantial morbidity and decreased patients' quality of life. Although the endoscopic diagnosis of early hypopharyngeal cancer is difficult, recent developments in advanced imaging endoscopy have enabled easier diagnosis of these lesions. Endoscopic resection of early hypopharyngeal cancer is a potential minimally invasive treatment that can preserve the function and quality of life of patients. Reports of this procedure are limited, however. We report a case of hypopharygeal cancer treated with endoscopic resection.

Intra-Abdominal Tuberculous Lymphadenitis Diagnosed Using an Endoscopic Ultrasonography-Guided ProCore Needle Biopsy

Intra-abdominal tuberculous lymphadenitis can mimic a variety of other abdominal disorders such as pancreatic cancer, metastatic lymph nodes, or lymphoma, which can make a proper diagnosis difficult. A correct diagnosis of intra-abdominal tuberculous lymphadenitis can lead to appropriate management. Endoscopic ultrasonography (EUS)-guided needle biopsy may be the procedure of choice for tissue acquisition when onsite cytopathology examination is unavailable because it is essential to obtain sufficient material suitable for the examination using an ancillary method, such as flow cytometry, molecular diagnosis, cytogenetics, or microbiological culture. We report a case of intra-abdominal tuberculous lymphadenitis diagnosed using an EUS-guided, 22-gauge histology new needle biopsy without an onsite cytopathology examination.

Rectal hyposensitivity and functional anorectal outlet obstruction are common entities in patients with functional constipation but are not significantly associated

BACKGROUND/AIMS

The causes of functional anorectal outlet obstruction (outlet obstruction) include functional defecation disorder (FDD), rectocele, and rectal intussusception (RI). It is unclear whether outlet obstruction is associated with rectal hyposensitivity (RH) in patients with functional constipation (FC). The aim of this study was to determine the association between RH and outlet obstruction in patients with FC.

METHODS

This was a retrospective study using a prospectively collected constipation database, and the population comprised 107 patients with FC (100 females; median age, 49 years). We performed anorectal manometry, defecography, rectal barostat, and at least two tests (balloon expulsion test, electromyography, or colon transit time study). RH was defined as one or more sensory threshold pressures raised beyond the normal range on rectal barostat. We investigated the association between the presence of RH and an outlet obstruction such as large rectocele (> 2 cm in size), RI, or FDD.

RESULTS

Forty patients (37.4%) had RH. No significant difference was observed in RH between patients with small and large rectoceles (22 [44.9%] vs. 18 [31%], respectively; p = 0.140). No significant difference was observed in RH between the non-RI and RI groups (36 [36.7%] vs. 4 [30.8%], respectively; p = 0.599). Furthermore, no significant difference in RH was observed between the non-FDD and FDD groups (19 [35.8%] vs. 21 [38.9%], respectively; p = 0.745).

CONCLUSIONS

RH and outlet obstruction are common entities but appear not to be significantly associated.

Does immunohistochemical staining have a clinical impact in early gastric cancer conducted endoscopic submucosal dissection?

AIM: To evaluate clinicopathologic parameters and the clinical significance related lymphovascular invasion (LVI) by immunohistochemical staining (IHCS) in endoscopic submucosal dissection (ESD).

METHODS: Between May 2005 and May 2010, a total of 348 lesions from 321 patients (mean age 63 ± 10 years, men 74.6%) with early gastric cancer (EGC) who met indication criteria after ESD were analyzed retrospectively. The 348 lesions were divided into the absolute (n = 100, differentiated mucosal cancer without ulcer ≤ 20 mm) and expanded (n = 248) indication groups after ESD. The 248 lesions were divided into four subgroups according to the expanded ESD indication. The presence of LVI was determined by factor VIII-related antigen and D2-40 assessment. We compared LVI IHCS-negative group with LVI IHCS-positive in each group.

RESULTS: LVI by hematoxylin-eosin staining (HES) and IHCS were all negative in the absolute group, while was observed in only the expanded groups. The positive rate of LVI by IHCS was higher than that of LVI by HES (n = 1, 0.4% vs n = 11, 4.4%, P = 0.044). LVI IHCS-positivity was observed when the cancer invaded to the mucosa 3 (M3) or submucosa 1 (SM1) levels, with a predominance of 63.6% in the subgroup that included only SM1 cancer (P < 0.01). In a univariate analysis, M3 or SM1 invasion by the tumor was significantly associated with a higher rate of LVI by IHCS, but no factor was significant in a multivariate analysis. There were no cases of tumor recurrence or metastasis during the median 26 mo follow-up.

CONCLUSION: EGCs of the absolute group are immunohistochemically stable. The presence of LVI may be carefully examined by IHCS in an ESD expanded indication group with an invasion depth of M3 or greater.

Successful treatment of early gastric cancer adjacent to a fundal varix by endoscopic submucosal dissection and endoscopic cyanoacrylate therapy

Endoscopic submucosal dissection (ESD) was developed for the en bloc resection of large early gastrointestinal neoplasms. A disadvantage of ESD is its technical difficulty, which requires advanced skills and is associated with a higher rate of complications. Endoscopic variceal obturation (EVO) using cyanoacrylate has emerged as the initial treatment of choice for acute gastric variceal bleeding. This procedure achieves hemostasis in 90% of cases. A 52-year-old patient with Child A alcoholic liver cirrhosis presented with early gastric cancer in the cardia and type 1 isolated gastric varices in the fundus. The two lesions were so close together that treatment was not easy. The lesions were managed successfully with a combination of ESD and EVO using cyanoacrylate.

Submucosal endoscopy, a new era of pure natural orifice translumenal endoscopic surgery (NOTES)

Natural orifice translumenal endoscopic surgery (NOTES) involves the intentional perforation of the viscera with an endoscope to access the abdominal cavity and perform an intraabdominal operation. In a brief time period, NOTES has been shown to be feasible in laboratory animal and human studies. Easy access to the peritoneal cavity and complete gastric closure should be secured before NOTES can be recommended as an acceptable alternative in clinical practice. The concept of submucosal endoscopy has been introduced as a solution to overcome these two primary barriers to human NOTES application. Its offset entry/exit access method effectively prevents contamination and allows the rapid closure of the entry site with a simple mucosal apposition. In addition, it could be used as an endoscopic working space for various submucosal conditions. Herein, the detailed procedures, laboratory results and human application of the submucosal endoscopy will be reviewed.

Recent Advances in Image-enhanced Endoscopy

The desire to better recognized such malignancies, which may be difficult to distinguish from inflammation or trauma, has accelerated the development of endoscopy with new optical technologies. Narrow-band imaging is a novel endoscopic technique that may enhance the accuracy of diagnosis using narrow-bandwidth filters in a red-green-blue sequential illumination system. Autofluorescence imaging is based on the detection of natural tissue fluorescence emitted by endogenous molecules. I-scan technology using a digital filter that modifies normal images through software functions, is the newly developed image-enhanced endoscopic technology from PENTAX. Flexible spectral imaging color enhancement enhances the visualization of mucosal structure and microcirculation by the selection of spectral transmittance with a dedicated wavelength. Confocal laser endomicroscopy images were collected with an argon beam with a scanning depth of 0 (epithelium) to 250 µm (lamina propria) and analyzed using the reflected light.

Optical biopsies by confocal endomicroscopy prevent additive endoscopic biopsies before endoscopic submucosal dissection in gastric epithelial neoplasias: a prospective, comparative study

BACKGROUND

Confocal laser endomicroscopy (CLE) allows real-time in vivo histologic evaluation of GI lesions. To our knowledge, there is no reported prospective study comparing endoscopic and optical biopsy using CLE before endoscopic submucosal dissection (ESD) with post-ESD histopathology.

OBJECTIVE

We compared endoscopic and optical biopsy before ESD and thereby assessed the ability of CLE to effectively diagnose and differentiate gastric epithelial neoplasia.

DESIGN

Single tertiary-care center, prospective comparative study.

SETTING

Soonchunhyang University Hospital, between September 2009 and April 2010.

PATIENTS

This study involved 31 patients with 35 gastric epithelial neoplasias, previously diagnosed by endoscopic biopsy, who were scheduled for ESD.

INTERVENTION

Target lesions were imaged in vivo by using CLE.

MAIN OUTCOME MEASUREMENTS

The overall accuracy of endoscopic and CLE diagnosis was compared with post-ESD histopathology.

RESULTS

In histopathology after ESD, 11 of 35 lesions (31.5%) were adenomas and 24 (68.5%) were adenocarcinomas. The overall accuracy of CLE diagnosis of gastric adenomas and adenocarcinomas was significantly higher at 94.2% (95% confidence interval [CI], 81.3-98.4), versus 85.7% (95% CI, 70.6-93.7) for endoscopic biopsy (P = .031). The overall accuracy of CLE diagnosis of differentiated and undifferentiated adenocarcinomas also was higher (95.4%; 95% CI, 78.2-99.1) than that of endoscopic biopsy (84.2%; 95% CI, 62.4-94.4) but did not differ significantly (P = .146).

LIMITATIONS

Single tertiary-care center experience and small patient number.

CONCLUSION

This study demonstrates the high accuracy of diagnosis of gastric epithelial neoplasia by using CLE. The use of CLE could possibly thus reduce the number of unnecessary biopsies and mistaken diagnoses before ESD.

Frozen Section Biopsy to Evaluation of Obscure Lateral Resection Margins during Gastric Endoscopic Submucosal Dissection for Early Gastric Cancer

Purpose

To determine the diagnostic utility of a frozen section biopsy in patients undergoing endoscopic submucosal dissection (ESD) for early gastric neoplasms with obscure margins even with chromoendoscopy using acetic acid and indigo carmine (AI chromoendoscopy).

Materials and Methods

The lateral spread of early gastric neoplasms was unclear even following AI chromoendoscopy in 38 patients who underwent ESD between June 2007 and May 2011. Frozen section biopsies were obtained by agreement of the degree of lateral spread between two endoscopists. Thus, frozen section biopsies were obtained from 23 patients (FBx group) and not in the other 15 patients (AI group).

Results

No significant differences were observed for size, histology, invasive depth, and location of lesions between the AI and FBx groups. No false positive or false negative results were observed in the frozen section diagnoses. Adenocarcinoma was revealed in three patients and tubular adenoma in one, thereby changing the delineation of lesion extent and achieving free lateral margins. The rates of free lateral resection margins and curative resection were significantly higher in the FBx group than those in the AI group.

Conclusions

Frozen section biopsy can help endoscopists perform more safe and accurate ESD in patients with early gastric neoplasm.

Endoscopic submucosal dissection for early gastric cancer: Quo vadis?

The diagnosis of early gastric cancer (EGC) is of great interest because its endoscopic and surgical treatment presents the best chance for a cure. With technical development, endoscopic submucosal dissection (ESD) has been widely performed for the curative treatment of EGC in Korea. Multinational studies of ESD for EGC will be the next missions that overcome these limitations and global guidelines will be processed for ESD for EGC.

Usefulness of magnifying endoscopy for iodine-unstained lesions in a high-risk esophageal cancer population

AIM: To investigate the usefulness of magnified observations of iodine-unstained esophageal lesions in the histological diagnosis of esophageal mucosa abnormalities, in high-risk esophageal cancer groups.

METHODS: The subjects included 38 patients who had at least one of the four criteria known to be high-risk factors for esophageal cancer. Following endoscopic observation, magnified observations were performed on iodine-unstained lesions of the esophagus. The total number of lesions was 43. These lesions were classified as type A (clear papilla), type B (fused papilla), and type C (non-visible papilla) according to the findings. Tissue biopsy was then carried out. Finally the histological findings were graded in terms of histological factors, and their relationships were compared.

RESULTS: Of the 43 lesions, 11 were type A, 17 were type B, and 15 were type C under magnifying endoscopy. Histological findings such as inflammatory cell infiltration and basal cell hyperplasia were significantly increased in type B and type C lesions compared with type A lesions (P < 0.05). Low-grade esophageal dysplasia was apparent in 1 (9%) of 11 type A lesions, in 3 (18%) of 17 type B lesions, and in 6 (40%) of 15 type C lesions, with the highest rate in type C.

CONCLUSION: Magnified observations of the esophagus, classified by papillary aspects using magnifying endoscopy of iodine-unstained lesions in high-risk esophageal cancer groups, are considered useful in estimating dysplasia and inflammation of esophageal mucosa.

[A case of jeujunogastric intussusception presented with hematemesis after distal gastrectomy]

Adult intussusception represents 5% of all cases of intussusception and accounts for only 1-5% intestinal obstructions. Intussusception is a rare complication after gastric surgery with an incidence estimated at 0.1%. Early diagnosis of the acute onset intussusception is critical because mortality rates increase abruptly with delay in surgical treatment. We present here a case of jejunogastric intussusception diagnosed by gastroscopy in a patient with a history of distal gastrectomy due to early gastric cancer who had experienced hematemesis.

Appropriate indications for endoscopic submucosal dissection of early gastric cancer according to tumor size and histologic type

BACKGROUND

Endoscopic submucosal dissection (ESD) is increasingly being performed for early gastric cancers (EGCs) that are larger than 2 cm and those that are not intestinal-type (IT) cancers by Lauren's classification. The technical feasibility of ESD for these EGCs has not been fully evaluated.

OBJECTIVE

To identify appropriate expanded indications for ESD of EGC.

DESIGN AND SETTING

A retrospective analysis of prospectively collected data was performed on consecutive patients who underwent ESD at a single tertiary center.

PATIENTS AND METHODS

In total, 487 EGCs in 461 patients treated by ESD were classified by size and histologic type: IT EGCs 2 cm or less (257 lesions in 235 patients), IT EGCs larger than 2 cm (172 lesions in 168 patients), and non-IT EGCs (58 lesions in 58 patients).

MAIN OUTCOME MEASUREMENTS

Curative resections were assessed among the 3 groups, and logistic regression analysis was used to analyze factors related to curative resection.

RESULTS

The rates of curative resection significantly decreased from IT EGCs 2 cm or less (88.7%) to IT EGCs larger than 2 cm (73.3%) to non-IT EGCs (37.9%). Tumor size (>3 cm), ulceration, histologic type (non-IT), and piecemeal resection were independently unfavorable factors in curative resection.

LIMITATIONS

Small sample size and short-term duration of follow-up study.

CONCLUSIONS

ESD with curative intent is technically most feasible for nonulcerative and IT EGCs smaller than 3 cm.

The Antro-pyloric Capsular Movement by Capsule Endoscopy

Background/Aims

Capsule endoscopy (CE) is used for various purposes. The aims of this study were to classify the types of antro-pyloric capsular movement in CE and to investigate the relationship between the types of capsular movement and clinical factors, including gastric emptying time (GET).

Methods

Out of 103 patients who received CE between January 2004 and July 2006, 82 patients (33 female, mean age of 50.6 years) were retrospectively analyzed for capsular movement; 21 patients were excluded because of the history of medications and previous surgeries. CE images were interpreted by a single investigator in relation to the GET and types of antro-pyloric capsular movement.

Results

Antro-pyloric capsular movement was classified into four patterns: type 1, large longitudinal to-and-fro movements in the antrum followed by passage through the pylorus without resistance; type 2, after large longitudinal to-and-fro movements, passage through the pylorus with resistance (> 1 minute); type 3, mixed pattern of type 1 and 4; type 4, weak movement. Median GET by CE were 14.1 minutes (range, 1.2-50.1), 21.7 minutes (6.2-154.9), 57.3 minutes (14.9-249.8), and 58.8 minutes (21.0-249.5) for type 1, 2, 3, and 4, respectively. GET in type 1 and 2 were significantly shorter than that in type 3 and 4 (p < 0.05). Ten diabetic patients presented with type 2 (n = 5), 3 (n = 3), and 4 (n = 2) patterns, but not with type 1.

Conclusions

Our results suggest the analysis of capsule movement using CE to be a possible method of evaluating the antro-pyloric movement.

A case of asymptomatic aspiration of a capsule endoscope with a successful resolution

Aspiration is a very rare complication of capsule endoscopy, but it is potentially life-threatening and should be considered an emergency requiring immediate intervention since it can evolve into major airway compromise and obstructive pneumonitis. We experienced a case of asymptomatic aspiration of a capsule in a 75-year-old man. The aspirated capsule was diagnosed on routine chest and abdomen X-rays to confirm its position after ingestion. The capsule was removed via bronchoscopy using a net, without sequelae, after inducing the patient to cough. To prevent this complication, a thorough history of swallowing disorders is needed before capsule ingestion, and patients with swallowing difficulties should have the capsule placed in the duodenum endoscopically. Moreover, on capsule aspiration, cough induction is the most effective method of capsule removal.

Toward the global standardization of endoscopic submucosal dissection proposal for 10 years from now - present and future view of Korea

Endoscopic submucosal dissection (ESD) is the main treatment of early gastric cancer in Korea. The Korean Society of Gastrointestinal Endoscopy (KSGE) has organized an ESD research group and made several plans to standardize pathologic and therapeutic points of view. This article is to introduce the present and future view of ESD in Korea.

Therapeutic outcomes in 1000 cases of endoscopic submucosal dissection for early gastric neoplasms: Korean ESD Study Group multicenter study

BACKGROUND

The technique of endoscopic submucosal dissection (ESD) was introduced to be able to obtain en bloc specimens of large early GI neoplasms. The drawback of ESD is its technical difficulty, which, consequently, is associated with a higher rate of complication and which requires advanced endoscopic techniques and a long procedure time.

OBJECTIVE

To assess the therapeutic outcome of ESD by expert endoscopists who have at least 3 years' experience of EMR in Korea.

DESIGN

A retrospective, multicenter study.

PATIENTS

From January 2006 to June 2007, 1000 early gastric cancers in 952 patients (502 men, 450 women; mean age 62.1 years, range 43-90 years) were treated by using ESD at 6 Korean ESD study group (KESG)-related university hospitals in Korea.

INTERVENTION

We performed ESD procedures with typical sequences (marking, incision, and submucosal dissection).

MAIN OUTCOME MEASUREMENTS

The rate of en bloc resection, incidence of complication, and length of procedure. Predetermined factors (various endoscopic and final pathologic features) for these outcomes.

RESULTS

The rates of en bloc resection, complete en bloc resection, vertical incomplete resection, and piecemeal resection were 95.3%, 87.7%, 1.8%, and 4.1%, respectively. The rates of delayed bleeding, significant bleeding, perforation, and surgery related to complication were 15.6%, 0.6%, 1.2%, and 0.2%, respectively. The mean procedure time was 47.8 +/- 38.3 minutes. The rates of en bloc resection differed significantly in relation to the location of the lesions (upper portion vs middle portion vs lower portion of the stomach, 88.6% vs 95.2% vs 96.0%, respectively; P = .02), presence of a scar (no vs yes, 96.0% vs 89.5%, respectively; P = .002), and histologic type (low-grade adenoma vs high-grade adenoma vs differentiated early gastric cancer vs undifferentiated early gastric cancer, 95.8% vs 94.6% vs 96.2% vs 83.8%, respectively; P = .007). The rates of delayed bleeding differed significantly in relation to location (upper portion vs lower portion of the stomach, 28.6% vs 13.8%, respectively; P = .003), the size of the tumor (>40 mm vs <20 mm, 28.6% vs 13.7%, respectively; P = .009), recurrent lesion (29.4% vs 15.1%, respectively; P = .024), and macroscopic type (flat vs elevated, 18.8% vs 12.4%, respectively; P = .047). Factors related to the longer procedure time were location (upper portion vs lower portion of the stomach, 64.8 vs 44.1 minutes, respectively; P < .001), the size of the tumor (>40 mm vs < 20 mm, 67.1 vs 42.0 minutes, respectively; P < .001), the presence of ulcer (54.6 vs 46.8 minutes; P < .045), and the presence of a scar (69.2 vs 45.0 minutes; P < .001).

CONCLUSIONS

ESD is an effective and safe therapy in the management of early gastric neoplasms. Endoscopists have to accept the need for advanced endoscopic techniques for performing ESD in the case of large lesions, scar lesions, undifferentiated cancers, or for the lesions in the upper portion of the stomach. Endoscopists require more experience to decrease complications in patients who have a large or recurrent lesion in the upper portion of the stomach; these lesions also take more time to complete the ESD procedure.

Endoscopic ultrasonography does not differentiate neoplastic from non-neoplastic small gallbladder polyps

AIM: To assess the ability of endoscopic ultrasonography (EUS) to differentiate neoplastic from non-neoplastic polypoid lesions of the gallbladder (PLGs).

METHODS: The uses of EUS and transabdominal ultrasonography (US) were retrospectively analyzed in 94 surgical cases of gallbladder polyps less than 20 mm in diameter.

RESULTS: The prevalence of neoplastic lesions with a diameter of 5-10 mm was 17.2% (10/58); 11-15 mm, 15.4% (4/26), and 16-20 mm, 50% (5/10). The overall diagnostic accuracies of EUS and US for small PLGs were 80.9% and 63.9% (P < 0.05), respectively. EUS correctly distinguished 12 (63.2%) of 19 neoplastic PLGs but was less accurate for polyps less than 1.0 cm (4/10, 40%) than for polyps greater than 1.0 cm (8/9, 88.9%) (P = 0.02).

CONCLUSION: Although EUS was more accurate than US, its accuracy for differentiating neoplastic from non-neoplastic PLGs less than 1.0 cm was low. Thus, EUS alone is not sufficient for determining a treatment strategy for PLGs of less than 1.0 cm.

A novel device for endoscopic submucosal dissection, the Fork knife

AIM: To introduce and evaluate the efficacy and technical aspects of endoscopic submucosal dissection (ESD) using a novel device, the Fork knife.

METHODS: From March 2004 to April 2008, ESD was performed on 265 gastric lesions using a Fork knife (Endo FS^®) (group A) and on 72 gastric lesions using a Flexknife (group B) at a single tertiary referral center. We retrospectively compared the endoscopic characteristics of the tumors, pathological findings, and sizes of the resected specimens. We also compared the en bloc resection rate, complete resection rate, complications, and procedure time between the two groups.

RESULTS: The mean size of the resected specimens was 4.27 ± 1.26 cm in group A and 4.29 ± 1.48 cm in group B. The en bloc resection rate was 95.8% (254/265 lesions) in group A and 93.1% (67/72) in group B. Complete ESD without tumor cell invasion of the resected margin was obtained in 81.1% (215/265) of group A and in 73.6% (53/72) of group B. The perforation rate was 0.8% (2/265) in group A and 1.4% (1/72) in group B. The mean procedure time was 59.63 ± 56.12 min in group A and 76.65 ± 70.75 min in group B (P < 0.05).

CONCLUSION: The Fork knife (Endo FS^®) is useful for clinical practice and has the advantage of reducing the procedure time.

Prevention of uncuffed hemodialysis catheter-related bacteremia using an antibiotic lock technique: A prospective, randomized clinical trial

As a result of the high rate of infection, the NKF-K/DOQI guidelines recommended that an uncuffed catheter (UC) should not be used for longer than three weeks. However, the findings of the Dialysis Outcomes and Practice Patterns Study recognized that 48% of new hemodialysis patients in the US and 75% in Europe used UC for temporary access during arteriovenous fistula or graft maturation. The antibiotic lock technique (ALT) has been recommended to prevent catheter-related bacteremia (CRB). Here, we prospectively evaluated the efficacy of catheter-restricted filling using an antibiotic lock solution in preventing CRB. A total of 120 new hemodialysis patients requiring a temporary catheter while waiting for placement and maturation of an arteriovenous fistula or graft were enrolled in this study. Patients with a UC were randomly assigned to receive either an antibiotic-heparin lock solution (antibiotic group: cefazolin 10 mg/ml, gentamicin 5 mg/ml, heparin 1000 U/ml) or a heparin lock solution (no-antibiotic group: heparin 1000 U/ml) as a catheter lock solution during the interdialytic period. The end point of the trial was CRB. CRB developed in seven (11.7%) patients in the no-antibiotic group (Staphylococcus aureus, two; Staphylococcus epidermidis, five) whereas only one patient in the antibiotic group had S. aureus bacteremia. CRB rates per 1000 catheter-days were 0.44 in the antibiotic group versus 3.12 in the no-antibiotic group (P=0.031). Kaplan-Meier analysis also showed that mean CRB-free catheter survival of 59 days (95% CI, 58-61 days) in the antibiotic group was greater than that in the no-antibiotic group (55 days; 95% CI, 50-59 days). The results suggest that ALT may be a beneficial means of reducing the CRB rate in hemodialysis patients with UC.

alpha-Melanocyte stimulating hormone (MSH) decreases cyclosporine a induced apoptosis in cultured human proximal tubular cells

The pathogenesis of chronic cyclosporine A (CsA) nephrotoxicity has not been elucidated, but apoptosis is thought to play an important role in CsA induced tubular atrophy. Recently Fas-Fas ligand system mediated apoptosis has been frequently reported in many epithelial cells as well as in T lymphocytes. We investigated the ability of CsA to induce apoptosis in cultured human proximal tubular epithelial cells and also the effect of alpha-MSH on them. Fas, Fas ligand, and an intracellular adaptor protein, Fas-associating protein with death domain (FADD) expression, and poly-ADP ribose polymerase (PARP) cleavage were also studied. CsA induced apoptosis in cultured tubular epithelial cells demonstrated by increased number of TUNEL positive cells and it was accompanied by a significant increase in Fas mRNA and Fas ligand protein expressions. FADD and the cleavage product of PARP also increased, indicating the activation of caspase. In alpha-MSH co-treated cells, apoptosis markedly decreased with downregulation of Fas, Fas ligand and FADD expressions and also the cleavage product of PARP. In conclusion, these data suggest that tubular cell apoptosis mediated by Fas system may play a role in tubular atrophy in chronic CsA nephrotoxicity and pretreatment of alpha-MSH may have a some inhibitory effect on CsA induced tubular cell apoptosis.

alpha-MSH decreases apoptosis in ischaemic acute renal failure in rats: possible mechanism of this beneficial effect

BACKGROUND

Apoptosis frequently occurs in acute renal injury but the molecular mechanisms responsible for this distinct form of cell death are largely unknown. Fas belongs to the tumour necrosis factor (TNF)/nerve growth factor superfamily and engagement by Fas ligand induces apoptosis in various epithelial cells. To investigate the role of apoptosis and associated mechanisms, we examined the occurrence of apoptosis and Fas and Fas ligand expression, and the therapeutic effect of alpha-melanocyte-stimulating hormone (alpha-MSH), a potent anti-inflammatory cytokine in an ischaemic acute renal failure (ARF) rat model. We also examined neutrophil infiltration together with intercellular adhesion molecule-1 (ICAM-1) expression because of their possible involvement in apoptosis due to their ability to release various inflammatory cytokines and reactive oxygen species.

METHODS

After unilateral nephrectomy in female Sprague-Dawley rats, the renal artery of the contralateral kidney was clamped for 40 min and reperfused. alpha-MSH or vehicle was injected intraperitoneally immediately after reperfusion and at 1, 6, or 24 h after reperfusion. The expression of Fas and Fas ligand was studied by western blot analysis and semiquantitative reverse transcription polymerase chain reaction (RT-PCR). Apoptosis was assessed by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labelling (TUNEL) method, and neutrophil infiltration by naphthol AS-D chloracetate staining. The degree of apoptosis, neutrophil infiltration, and Fas and Fas ligand, and ICAM-1 expression, as well as biochemical and histological data were compared between the alpha-MSH and the vehicle-treated groups.

RESULTS

Intraperitoneally administered alpha-MSH significantly reduced renal injury, measured by blood urea nitrogen (BUN) and creatinine and by the degree of tubular necrosis (109.6+/-7.1/54.7+/-3.1 mg/dl for BUN, and 1.6+/-0.2/1.03+/-0.06 mg/dl for creatinine 24 h after ischaemia) (5.4+/-0.8/2.6+/-0.3 for injury score 24 h after ischaemia). Ischaemia caused an increase in Fas and Fas ligand expression and was accompanied by morphological evidence of apoptosis. alpha-MSH significantly reduced the degree of apoptosis, as well as Fas and Fas ligand expression (mean apoptotic cell number, 41.7+/-3.5/14.2+/-2.2 per x200 field at 24 h after ischaemia. Fas protein expression: sham, 1409+/-159 DI (densitometric index); vehicle/alpha-MSH, 2818+/-635/1306+/-321 DI at 24 h and 5542+/-799/2867+/-455 DI at 72 h after ischaemia. Fas ligand protein expression: sham, 1221+/-181 DI; vehicle/alpha-MSH, 2590+/-85/1279+/-169 DI at 4 h, 4376+/-268/2432+/-369 DI at 24 h and 5200+/-648/2253.7+/-1104 DI at 72 h after ischaemia). Neutrophil infiltration and ICAM-1 expression were also significantly reduced in alpha-MSH group (neutrophil infiltration: vehicle/ alpha-MSH, 5.05+/-1.8/1.59+/-0.4) (ICAM-1 expression, vehicle/alpha-MSH 0.46+/-0.21/0.29+/-0.19).

CONCLUSION

These results suggest that apoptosis clearly contributes to tubular cell loss in ischaemia/reperfusion (I/R) injury possibly by neutrophil-mediated pathways or an increase in Fas-Fas ligand expression. The observed beneficial effect of alpha-MSH could be related to these mechanisms.

A case of Rathke's Cleft Cyst inflammation presenting with diabetes insipidus

Rathke's Cleft Cyst (RCC), which is located at the intrasellar region, is considered to be the distended remnants of Rathke's pouch, an invagination of the stomodeum. Lined with columnar or cuboidal epithelium of ectodermal origin, RCC usually contains mucoid material and it is found in 13-22% of normal pituitary glands. The cyst rarely leads to the development of symptoms but, when it does, the most common presenting symptoms are headache, visual impairment, hypopituitarism and hypothalamic dysfunction. However, in some cases it presents symptoms of diabetes insipidus, decreased libido and impotence. Recently we experienced a case of RCC inflammation presenting with diabetes insipidus and treated with transsphenoidal surgery. To our knowledge, this is the first report of RCC presenting with symptoms of diabetes insipidus in Korea.

Role of vascular endothelial growth factor in diabetic nephropathy

BACKGROUND

Vascular endothelial growth factor (VEGF) is a potent cytokine that is considered to be an important mediator in the pathogenesis of endothelial dysfunction in diabetes.

METHODS

This study investigates the effect of high glucose on the signaling and production of VEGF in rat mesangial cells in culture and measures the urinary VEGF level in patients with different stages of diabetic nephropathy. To elucidate the role of VEGF in vivo further, expression of VEGF in control and diabetic kidneys was examined using immunohistochemistry.

RESULTS

A high ambient glucose concentration in the culture medium increased VEGF mRNA expression and protein production within 3 h in a concentration-dependent manner. A protein kinase C (PKC) inhibitor and PKC down-regulation inhibited glucose-induced increases in VEGF production. Urinary excretion of VEGF significantly increased according to the degree of proteinuria in patients with diabetes. A weak but significant correlation was found between urinary VEGF excretion and the levels of serum creatinine, creatinine clearance, microalbuminuria, and proteinuria. Immunohistochemistry revealed marked differences in the extent of mesangial VEGF staining between diabetic and control kidneys. Pronounced up-regulation of VEGF was observed in the glomerular epithelial cell in the early phase of diabetic kidney disease, whereas widespread expression of VEGF was found in the tubular segments, especially the proximal segment, in advanced diabetic nephropathy.

CONCLUSIONS

These results suggest that VEGF may play a role in the pathogenesis of diabetic nephropathy.

ACE gene polymorphism and renal responsiveness to ACE inhibitors in IgA nephropathy patients

We examined the renal responsiveness to ACE inhibitor in IgA nephropathy (IgAN) patients according to the grouping of ACE gene polymorphism. Sixty one patients diagnosed as IgAN by renal biopsy and prescribed with ACE inhibitors were enrolled. Genomic DNA was extracted from whole blood and PCR was performed. The I/D polymorphism was determined by the presence of the 287 bp fragment in intron 16 of chromosome 17. During the follow-up period (mean; 44.6 months, median: 44.5 months, 5 to 113 months), the blood pressure of 61 patients was controlled below 130/80 mmHg. The renal responsiveness was determined by the degree of changes of proteinuria at 12 months after initiation of ACE inhibitors and by the slope of reciprocal variation of the serum creatinine against follow-up duration ¿(1/Cr2-1/Cr1)/durations¿. The distribution of the II, ID and DD genotype among 61 patients was 21, 16 and 24 patients, respectively. There were no differences among three genotypes in age, sex, the number of patients with initial blood pressure over 140/90 mmHg, initial serum creatinine level, the number of patients with initial azotemia (> 1.4 mg/dL) and with initial 24-hr proteinuria amount over 2.0 g. Significant anti-proteinuric effect of ACE inhibitor was found in IgAN (p = 0.001), but no significant difference was found among genotypes. Significant difference (p = 0.011) was noticed between II type and DD type in the slope of reciprocal variation of the serum creatinine against follow-up duration. In conclusion, efficacy of ACE inhibitors on renal function preservation in IgAN was more pronounced in DD genotype than II genotype.

Homocyst(e)ine and atherosclerosis in patients on chronic hemodialysis

Hyperhomocyst(e)inemia is an established risk factor for atherosclerosis. We performed this study to identify the correlating variables and risk factors for atherosclerosis, as measured by the atherosclerotic score (AS), and to determine the relative risk for cardiovascular disease in relation to plasma homocyst(e)ine levels in patients on chronic hemodialysis. We evaluated and measured 61 patients on chronic hemodialysis for clinical and biochemical parameters including atherosclerotic score (AS) and plasma homocyst(e)ine. We divided patients into high and low groups, first, by the mean AS, and second, by the median value of plasma total homocyst(e)ine levels. Then we compared the variables between the two groups. Out of the 61 patients, the median plasma total homocyst(e)ine level was 24.4 micromol/L (mean+/-SD, 27.7+/-17.4; range, 9.8-127.4 micromol/L), and the median AS was 5 (mean+/-SD, 6.2+/-2.8; range, 3-13) out of a possible 20 points. AS was significantly correlated with plasma total homocyst(e)ine levels (r=0.37) and age (r=0.67). Through multivariate analysis, plasma total homocyst(e)ine level and age were determined as significant risk factors for the high-AS group (p<0.05). However, plasma total homocyst(e)ine level did not correlate with age (p>0.05). Eighteen of the 61 patients, presented with cardiovascular disease until the present study, had an AS>6. Cardiovascular disease was found more often in the high-homocyst(e)ine group (>24.4 micromol/L) than in the low-homocyst(e)ine group (odds ratio, 9.3; 95% confidence interval, 2.3-37.4). Regardless of age, hyperhomocyst(e)inemia (especially homocyst(e)ine levels >24.4 micromol/L) is a risk factor that can be modified for the development of cardiovascular disease in patients on chronic hemodialysis.

Degradation of human immunoglobulins and cytotoxicity on HeLa cells by live Trichomonas vaginalis

The present study was undertaken to determine whether live T. vaginalis degrades human secretory IgA, serum IgA and IgG molecules. Human immunoglobulins were exposed to live trophozoites, parasite lysate, and excretory-secretory product (ESP) of T. vaginalis. To determine the fragmentation of immunoglobulins, the reaction sample was subjected to SDS-PAGE and EITB, and peroxidase conjugated antihuman IgA and IgG were used as probes. Live trophozoites degraded secretory IgA. Serum IgA and IgG, and degradation were pressed forward by the prolongation of the incubation time and by increasing the number of trichomonads respectively. Also the lysates and ESP of trichomonads degraded IgA and IgG. The cysteine and serine proteinase inhibitors such as E-64, antipain, iodoacetic acid, iodoacetamide, TLCK reduced the ability of cleaving immunoglobulins. The proteinase activity and cytotoxicity of T. vaginalis to HeLa cells were decreased when live T. vaginalis was treated with metallo-proteinase inhibitor as well as cysteine and serine proteinase inhibitors. These results suggest that proteinase secreted from live T. vaginalis may play a part role in host pathogenesis by T. vaginalis, and the cleaving ability of host immunoglobulins by the proteinase may contribute as a one of immune evasion mechanism for parasite survival in the host.

Mycobacterium fortuitum peritonitis associated with continuous ambulatory peritoneal dialysis

Runyon group IV atypical mycobacteria, Mycobacterium fortuitum, is an environmental organism and is capable of producing a variety of clinical infections such as cutaneous infection, abscess and pulmonary and ocular infection. Rarely, it has been a documented cause of peritonitis in patients receiving continuous ambulatory peritoneal dialysis (CAPD). We report a case of M. fortuitum peritonitis in a patient undergoing CAPD and emphasize the importance of mycobacterial cultures in patients with CAPD-associated peritonitis whose routine culturing yields no organisms repeatedly.

Thyrotropin binding inhibiting antibody (TBIAb) in Graves' disease

To determine the nature of TBIAb in Graves’ disease, TBIAb was measured and correlated to various clinical, thyroid functional indices and thyroid autoantibodies. The incidence of TBIAb in untreated Graves’ patients, patients in treatment and those in remission was 70.9%, 53.1% and 19.2%, respectively. With respect to clinical indices, there was no correlation between TBIAb and the presence of exophthalmos or periodic paralysis, onset age, diseage duration or sex, but goiter size on initial examination did show significant correlation (r=0.95). Regarding the indices of thyroid function, 20min 99m-Tc uptake (r=0.28), free T4 index (r=0.39) and free T3 index (r=0.40) were well correlated to TBIAb activity. Also Grave’s patients with strong antimicrosomal activity exhibited a high incidence of TBIAb positiveness.