Prophylactic clipping using the over-the-scope clip (OTSC) system after complex ESD and EMR of large colon polyps.

BACKGROUND: Delayed bleeding is the most frequent complication after endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) of large colon polyps. Today, prophylactic clipping with through-the-scope clips (TTSCs) is commonly used to reduce the risk of bleeding. However, the over-the-scope clip (OTSC) system might be superior to TTSCs in achieving hemostasis. This study aims to evaluate the efficacy and safety of prophylactic clipping using the OTSC system after ESD or EMR of large colon polyps. METHODS: This is a retrospective analysis of a prospective collected database from 2009 until 2021 of three endoscopic centers. Patients with large (≥ 20 mm) colon polyps were enrolled. All polyps were removed by either ESD or EMR. After the resection, OTSCs were prophylactically applied on parts of the mucosal defect with a high risk of delayed bleeding or/and perforation. The main outcome measurement was delayed bleeding. RESULTS: A total of 75 patients underwent ESD (67%, 50/75) or EMR (33%, 25/75) in the colorectum. The mean resected specimen diameter was 57 mm ± 24.1 (range 22-98 mm). The mean number of OTSCs placed on the mucosal defect was 2 (range 1-5). None of the mucosal defects were completely closed. Intraprocedural bleeding occurred in 5.3% (ESD 2.0% vs. EMR 12.0%; P = 0.105), and intraprocedural perforation occurred in 6.7% (ESD 8% vs. EMR 4%; P = 0.659) of the patients. Hemostasis was achieved in 100% of cases of intraprocedural bleeding, whereas two patients required surgical conversion due to intraprocedural perforation. Among the remaining 73 patients who received prosphylactic clipping, delayed bleeding occurred in 1.4% (ESD 0% vs. EMR 4.2%; P = 0.329), and delayed perforation occurred in 0%. CONCLUSIONS: The prophylactic partial closure of large post-ESD/EMR mucosal defects using OTSCs could serve as an effective strategy to reduce the risk of delayed bleeding and perforation. The prophylactic partial closure of large complex post-ESD/EMR mucosal defects using OTSCs could serve as an effective strategy to reduce the risk of delayed bleeding and perforation.

Clinical implantation of 92 VACStents in the upper gastrointestinal tract of 50 patients-applicability and safety analysis of an innovative endoscopic concept.

Introduction: Endoscopic vacuum therapy (EVT) has emerged as a promising treatment option for upper gastrointestinal wall defects, offering benefits such as evacuation of secretions and removal of wound debris by suction, and reduction and healing of wound cavities to improve clinical outcomes. In contrast, covered stents have a high rate of migration and lack functional drainage, while endoluminal EVT devices obstruct the GI tract. The VACStent is a novel device that combines the benefits of EVT and stent placement. Its design features a fully covered Nitinol-stent within a polyurethane sponge cylinder, enabling EVT while maintaining stent patency. Methods: This study analyzes the pooled data from three different prospective study cohorts to assess the safe practicality of VACStent placement, complete leak coverage, and effective suction-treatment of esophageal leaks. By pooling the data, the study aims to provide a broader base for analysis. Results: In total, trans-nasal derivation of the catheter, suction and drainage of secretion via vacuum pump were performed without any adversity. In the pooled study cohort of 92 VACStent applications, the mean stent indwelling time was 5.2 days (range 2-8 days) without any dislocation of the device. Removal of the VACStent was done without complication, in one case the sponge was lost but subsequently fully preserved. Minor local erosions and bleeding and one subsequent hemostasis were recorded unfrequently during withdrawal of the device (5.4%, 5/92) but no perforation or pressure ulcer. Despite a high heterogeneity regarding primary disease and pretreatments a cure rate of 76% (38/50 patients) could be achieved. Discussion: In summary, insertion and release procedure was regarded as easy and simple with a low potential of dislocation. The VACStent was well tolerated by the patient while keeping the drainage function of the sponge achieving directly a wound closure by continuous suction and improving the healing process. The implantation of the VACStent provides a promising new procedure for improved clinical treatment in various indications of the upper gastrointestinal wall, which should be validated in larger clinical studies.Clinical Trial Registration: Identifier [DRKS00016048 and NCT04884334].

Novel modified endoscopic mucosal resection of large GI lesions (> 20 mm) using an external additional working channel (AWC) may improve R0 resection rate: initial clinical experience.

BACKGROUND: En-bloc resection of large, flat dysplastic mucosal lesions of the luminal GI tract can be challenging. In order to improve the efficacy of resection for lesions ≥2 cm and to optimize R0 resection rates of lesions suspected of harboring high-grade dysplasia or early adenocarcinoma, a novel grasp and snare EMR technique utilizing a novel over the scope additional accessory channel, termed EMR Plus (EMR+), was developed. The aim of this pilot study is to describe the early safety and efficacy data from the first in human clinical cases. METHODS: A novel external over-the-scope additional working channel (AWC) (Ovesco, Tuebingen, Germany) was utilized for the EMR+ procedure, allowing a second endoscopic device to be used through the AWC while using otherwise standard endoscopic equipment. The EMR+ technique allows tissue retraction and a degree of triangulation during endoscopic resection. We performed EMR+ procedure in 6 patients between 02/2018-12/2018 for lesions in the upper and lower GI tract. RESULTS: The EMR+ technique utilizing the AWC was performed successfully in 6 resection procedures of the upper and/or lower GI tract in 6 patients in 2 endoscopy centers. All resections were performed successfully with the EMR+ technique, all achieving an R0 resection. No severe adverse events occurred in any of the procedures. CONCLUSIONS: The EMR+ technique, utilizing an additional working channel, had an acceptable safety and efficacy profile in this preliminary study demonstrating it's first use in humans. This technique may allow an additional option to providers to remove complex, large mucosal-based lesions in the GI tract using standard endoscopic equipment and a novel AWC device.

Endoscopic submucosal dissection with a novel high viscosity injection solution (LiftUp) in an ex vivo model: a prospective randomized study.

Introduction Endoscopic submucosal dissection (ESD) is increasingly being used in the western world. Submucosal injectates are an essential tool for the ESD procedure. In this study, we evaluated a novel copolymer injectate (LiftUp, Ovesco, Tübingen Germany) in an established ESD model (EASIE-R) in comparison to existing submucosal injectables. Materials and methods We conducted a prospective, randomized ex vivo study performing ESD with three injectates: LiftUp, hydroxyethyl starch (HAES 6 %) and normal saline solution (NaCl 0.9 %). A total of 60 artificial lesions, each 3 × 3 cm in size, were resected in an ex vivo porcine model, utilizing one of the three studied injectates (n = 20 ESDs per injectate). Study parameters were: en bloc resection rate, perforation rate, lifting property, time of injection, injectate volume, general ESD procedure time, and overall procedure time. Results All 60 lesions were successfully resected using the standard ESD technique. LiftUp had no procedure related perforations, one perforation occurred in the HAES group, and two perforations in the NaCl group ( P  > 0.05). Furthermore, adequate lifting was achieved in 16/20 (80 %) using LiftUp, 6/20 (30 %) in the HAES group and 6/20 (30 %) in the NaCl group ( P  < 0.0002). En bloc resection was achieved in 19 (95 %) with LiftUp, in 20 (100 %) with HAES, and in 16 (80 %) with NaCl. General ESD procedure time and overall procedure time were not different among the three groups. Conclusion LiftUp appears to be a safe alternative to established fluids for ESD. It had a significantly improved lifting effect and required significantly less injected volume compared to well-established lifting solutions.

A retrospective analysis of adverse effects of an in vivo fluoroquinolone antibiotic enrofloxacin treatment on oocyte quality in the common marmoset.

Here we report a retrospective analysis of negative effects of routine enrofloxacin treatment of recurrent diarrhea on the ovary and the developing oocytes of the common marmoset, a small New World primate. The most deleterious effect on oocytes was observed about two months post treatment suggesting that the enrofloxacin effect is on early growing follicles. Manifestations of toxicity included decreased numbers of growing follicles and recovered culturable oocytes, as well as signs of early atresia of granulosa cells. In addition, increased amounts of holed stroma after treatment strongly suggested increased death of the early growing follicles. Of the oocytes judged to be of adequate quality for culture, maturation rates were not affected but fertilization of in vitro matured MII oocytes and subsequent cleavage rates were severely reduced in the enrofloxacin treated animals. Further, the arrested oocytes, which failed to mature or fertilize, showed obvious meiotic spindle abnormalities.

Multicenter evaluation of first-line endoscopic treatment with the OTSC in acute non-variceal upper gastrointestinal bleeding and comparison with the Rockall cohort: the FLETRock study.

INTRODUCTION: The over-the-scope clip (OTSC) overcomes limitations of standard clips and achieves a more efficient and reliable hemostasis in non-variceal upper gastrointestinal bleeding (NVUGIB). The study aims to evaluate mortality, rebleeding, and mortality after rebleeding of patients in whom the OTSC was used as the first-line endoscopic treatment (FLET) of NVUGIB. PATIENTS AND METHODS: In total, 118 patients (FLET cohort) with a median age of 73.5 years (range 29-93 years; mean (±SD) 71.39 ± 12.39 years) were included. The distribution of patients with respect to risk category revealed a median Rockall score of 7 (range 3-10). For hypothesis testing, the FLET cohort was categorized into three risk groups taking into account the Rockall score: low risk [Rockall risk category (RRC ≤3)], moderate risk (RRC 4-7), and high risk (RRC ≥8). Event rates (mortality, rebleeding, and mortality after rebleeding) observed per risk group were compared to predicted event rates (Rockall cohort) using Fisher's Exact Test. RESULTS: Primary successful hemostasis (PSH) was achieved in 92.4% either by FLET alone or in combination with an additional hemostasis technique in 1.7% (SCS = secondary clinical success). In 7.5% of the FLET cohort PSH could not be achieved. Compared to RRC prediction, mortality after rebleeding was significantly reduced from 27.9 to 10.9% in the high-risk group (RRC ≥8) treated with FLET (p < 0.011). Furthermore, the occurrence of rebleeding or continued bleeding was significantly lower in the moderate risk group (RRC 4-7) with 4.9% as well as in the high-risk group (RRC ≥8) with 21.4% compared to the Rockall cohort 24.0 and 53.2%, respectively (p < 0.001). CONCLUSIONS: This study shows that OTSC is superior to standard care and FLET reduces significantly rebleeding and rebleeding-associated mortality in NVUGIB. For this reason, OTSC could be the treatment of choice as the first-line treatment as an alternative to standard hemostasis techniques in high-risk patients.

Detection of cross-sex chimerism in the common marmoset monkey (Callithrix jacchus) in interphase cells using fluorescence in situ hybridisation probes specific for the marmoset X and Y chromosomes.

Chimerism associated with placental sharing in marmosets has been traditionally analysed using conventional chromosome staining on metaphase spreads or polymerase chain reaction. However, the former technique requires the presence of proliferating cells, whereas the latter may be associated with possible blood cell contamination. Therefore, we aimed to develop a single-cell analysis technique for sexing marmoset cells. We applied fluorescent in situ hybridisation (FISH) to cell nuclei using differentially labelled X and Y chromosome-specific probes. Herein we present the validation of this method in metaphase cells from a marmoset lymphoblastoid cell line, as well as application of the method for evaluation of cross-sex chimerism in interphase blood lymphocytes and haematopoietic bone marrow cells from marmosets of same- and mixed-sex litters. The results show conclusively that haematopoietic cells of bone marrow and leucocytes from blood are cross-sex chimeric when the litter is mixed sex. In addition, single samples of liver and spleen cell suspensions from one individual were tested. Cross-sex chimerism was observed in the spleen but not in liver cells. We conclude that FISH is the method of choice to identify cross-sex chimerism, especially when combined with morphological identification of nuclei of different cell types, which will allow a targeted tissue-specific analysis.

Critical estradiol dose optimization for oocyte in vitro maturation in the common marmoset.

The aim of the present study was to critically evaluate the effect of different concentrations of estradiol (E2) during IVM of common marmoset (Callithrix jacchus) oocytes from antral follicles. The doses tested were 0, 0.1, 1, or 10 µg/mL E2 (referred to as 0 E2, 0.1 E2, 1 E2, and 10 E2 groups). After a preincubation, the concentration of E2 in IVM drops under oil was approximately 20% of the amount added (0.02; 0.2 and 1.9 µg/mL, respectively) because of absorption into the oil. Oocyte progression to metaphase II was significantly higher in the 0.1 E2 group than that in the absence of E2. With progressively higher doses, the maturation rate tended to decrease suggesting an overdose effect. Furthermore, the total first cleavage rate was significantly higher in the 0.1 E2 group than that in the 0 E2 group and decreased progressively with further increases in E2 concentration, with the 10 E2 group showing the same low rate as without E2. The oocytes which failed to cleave, after maturation in 10 E2, showed obvious signs of overdose with the highest rates of degeneration and abnormal spindle form, and an absence of embryo progression. In contrast to these obvious negative effects on the oocyte, 10 E2 was the only group in which a significant increase in radial cumulus expansion was observed. The concentration 0.1 E2, which is 10 times lower than the most commonly used E2 dose, produced the best results in all oocyte factors evaluated. These results represent the first study for a primate species showing a strong positive effect of E2 on oocyte maturation and embryo development, but only at the optimal concentration, and emphasize the critical limits of the optimal concentration range.

Numerical chromosome disorders in the common marmoset (Callithrix jacchus)--comparison between two captive colonies.

BACKGROUND: Chromosomal analyses were performed for marmosets from two colonies - Deutsches Primatenzentrum (DPZ) and Biomedical Primate Research Centre (BPRC). Chlorine-based disinfectants are used in DPZ; no chemical disinfection is applied in BPRC. METHODS: The rates of chromosomal non-disjunction, polyploidy and endoreduplication were investigated after G-banding. RESULTS: For DPZ monkeys, the mean rates of non-disjunction were 7.6% for bone marrow and 11.3% for lymphocytes. The polyploidy level was 2.5% in bone marrow and 0.8% in blood. Frequency of endoreduplication in bone marrow and in leucocytes was 0.5% and 0.8%, respectively. For BPRC, the rate of non-disjunction in leucocytes (1.3%) was significantly lower than that for DPZ; the polyploidy rate (0.2%) in blood was lower than that in DPZ; endoreduplication was not observed. CONCLUSION: The levels of chromosomal disorders are elevated for DPZ colony. We suggest that the increased rate of chromosomal disorders in DPZ marmosets can be related to the chemical disinfection of their environment.

[Endoscopic submucosal dissection]. / Endoskopische Submukosadissektion.

Endoscopic submucosal dissection (ESD) was developed in Japan but has now also become permanently established in various centers in Europe. ESD is an endoscopic en bloc mucosal resection technique for the treatment of early cancers with a diameter >1 cm and also superficial precancerous lesions, which could only be removed unsatisfactorily in several fragments or with uncertain lateral safety margins using previous loop excision procedures. Using ESD a lesion is excised after circular marking and generous submucosal injection with a safety margin of approximately 5 mm and subsequently resected at the level of the submucosa with a 1-3 mm short diathermic knife. ESD requires high technical skills in interventional endoscopy and is more time-consuming than snare resection techniques. However, numerous studies have shown a clear superiority for ESD with respect to the R0 resection rate and the local recurrence rate. The present article gives a current review of the use of ESD in the upper and lower gastrointestinal tract and demonstrates perspectives of the procedure.

A case report of spontaneous opening of congenitally fused labia in a female common marmoset (Callithrix jacchus) followed by pregnancy and birth of twins.

A first case of spontaneous opening of congenitally fused labia (CFL phenotype) in a captive common marmoset followed by pregnancy and birth is presented here. The occurrence of this phenotype has been previously published in captive marmosets, but so far the etiology is unknown.