Does an Extraoral Suction Device Reduce Aerosol Generation and Prevent Droplet Exposure to the Examiner during Esophagogastroduodenoscopy?

Esophagogastroduodenoscopy (EGD) is an aerosol-generating procedure. A major challenge in the COVID-19 era is how to prevent the spread of aerosols and droplets in endoscopic units. We evaluated the effectiveness of an extraoral suction device in preventing indoor aerosol diffusion and droplet exposure for examiners. The study involved 61 patients who underwent EGD at our institution from 1 February to 31 March 2022. To determine whether aerosol spread increases before or after EGD examination with an extraoral suction device located in front of the patient's mouth, aerosols of 0.3, 0.5, 1, 3, 5, and 10 µm were measured with a handheld particle counter. The degree of contamination of the plastic gowns on the examiners was assessed using the rapid adenosine triphosphate test. The extraoral suction device significantly reduced the diffusion of large particles (3, 5, and 10 µm) after finishing the EGD examination. However, the diffusion of small particles (0.3 and 0.5 µm) was significantly increased. This extraoral suction device was effective in reducing large particle diffusion during EGD examination but was limited for minimizing small particle diffusion or droplet exposure to the examiner.

Long-term outcomes of over-the-scope clip for refractory gastrointestinal diseases.

BACKGROUND: The Over-The-Scope Clip (OTSC) can effectively treat refractory gastrointestinal diseases. However, most reports have focused on short-term effectiveness. We examined clinical outcomes of the deployed clips and long-term characteristics. MATERIAL AND METHODS: Of 47 patients with OTSC treatment, 35 with follow-up periods of ≥3 months were retrospectively examined. The indications were 11 bleedings, 17 perforations, and seven fistulas. The observation period was defined as medium-term (3 to <12 months) or long-term (≥12 months). The primary outcome was the clinical success rate without disease recurrence. The secondary outcomes were the complication rate, survival duration, and clip retention rate. RESULTS: The medium- and long-term clinical success rates were 100% during the observation period (median, 44 months; range, 3-78 months). The complication rate was 2.9% (n = 1). The median survival time was 1,634 days for bleeding, 1,757 days for perforation, and 444 days for fistulas. The overall clip retention rates were 56.4%, 38.1%, 30.9%, and 25.9% after one, six, and 12 months and at the final follow-up, respectively. The average clip retention duration was 244 days in bleeding, 656 days in perforations, and 188 days in fistulas. CONCLUSIONS: Regardless of clip detachment, the OTSC can be effective in long-term.

Evaluating the Effect of Lenvatinib on Sorafenib-Resistant Hepatocellular Carcinoma Cells.

Hepatocellular carcinoma (HCC) is one of the major causes of cancer-related deaths worldwide. Sorafenib has been used as a first-line systemic treatment for over a decade. However, resistance to sorafenib limits patient response and presents a major hurdle during HCC treatment. Lenvatinib has been approved as a first-line systemic treatment for advanced HCC and is the first agent to achieve non-inferiority against sorafenib. Therefore, in the present study, we evaluated the inhibition efficacy of lenvatinib in sorafenib-resistant HCC cells. Only a few studies have been conducted on this topic. Two human HCC cell lines, Huh-7 and Hep-3B, were used to establish sorafenib resistance, and in vitro and in vivo studies were employed. Lenvatinib suppressed sorafenib-resistant HCC cell proliferation mainly by inducing G1 cell cycle arrest through ERK signaling. Hep-3B sorafenib-resistant cells showed partial cross-resistance to lenvatinib, possibly due to the contribution of poor autophagic responsiveness. Overall, the findings suggest that the underlying mechanism of lenvatinib in overcoming sorafenib resistance in HCC involves FGFR4-ERK signaling. Lenvatinib may be a suitable second-line therapy for unresectable HCC patients who have developed sorafenib resistance and express FGFR4.

Galectin-9 Induces Mitochondria-Mediated Apoptosis of Esophageal Cancer In Vitro and In Vivo in a Xenograft Mouse Model.

Galectin-9 (Gal-9) enhances tumor immunity mediated by T cells, macrophages, and dendritic cells. Its expression level in various cancers correlates with prognosis. Furthermore, Gal-9 directly induces apoptosis in various cancers; however, its mechanism of action and bioactivity has not been clarified. We evaluated Gal-9 antitumor effect against esophageal squamous cell carcinoma (ESCC) to analyze the dynamics of apoptosis-related molecules, elucidate its mechanism of action, and identify relevant changes in miRNA expressions. KYSE-150 and KYSE-180 cells were treated with Gal-9 and their proliferation was evaluated. Gal-9 inhibited cell proliferation in a concentration-dependent manner. The xenograft mouse model established with KYSE-150 cells was administered with Gal-9 and significant suppression in the tumor growth observed. Gal-9 treatment of KYSE-150 cells increased the number of Annexin V-positive cells, activation of caspase-3, and collapse of mitochondrial potential, indicating apoptosis induction. c-Jun NH2-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38) phosphorylation were activated and could be involved in apoptosis. Therefore, Gal-9 induces mitochondria-mediated apoptosis of ESCC and inhibits cell proliferation in vitro and in vivo with JNK and p38 activation.

Efficacy of sufficient operation view by ring-shaped thread counter traction for safer duodenal ESD.

Background: Duodenal ESD is considered especially difficult with perforation and bleeding. This study assessed safer duodenal ESD procedures, especially with regard to obtaining a good operation view using a ring-thread method and closure of a post-ESD artificial ulcer. Methods: From 2013 to 2015, 17 patients who were diagnosed with duodenal adenoma or early duodenal cancer >20 mm in diameter underwent conventional ESD (C group). From 2016 to 2017, 12 patients underwent ring-shaped thread counter traction ESD with hemoclips and/or Over-The-Scope Clip (OTSC) (Ovesco Endoscopy GmbH, Tuebingen, Germany) closure of post ESD artificial ulcer (ring group). An observational study between the C group and Ring group was conducted. The primary outcome was perforation events during ESD (UMIN000026184). Results: There was a significant difference in perforation during ESD with five cases vs. 0 case in C and ring groups (p = .038). For bleeding that needed to be coagulated by forceps during ESD, there was a significant difference with four cases in the C group (p = .07). The total procedure time was 96.6 ± 28.2 and 72.8 ± 24.2 (min) with a significant difference (p = .027). Conclusions: Ring-shaped thread counter traction makes the most difficult duodenal ESD safer and easier without complications.

Rare Primary Esophageal Paget's Disease Diagnosed on a Large Bloc Specimen Obtained by Endoscopic Mucosal Resection.

Primary esophageal Paget's disease is rare. Only a few case reports have described the intraepithelial papillary capillary loop (IPCL) pattern obtained by magnified Narrow Band Imaging (M-NBI) endoscopy in this rare pathology. This report highlights the usefulness of M-NBI and the successful diagnosis using a large bloc specimen obtained by endoscopic mucosal resection with the cap method (EMR-c). A 53-year-old man was referred to endoscopic examination for dysphagia. The endoscopic image revealed a ring-shaped scarring of the esophagus suggestive for eosinophilic esophagitis. The IPCL pattern by M-NBI endoscopy showed an inflammatory pattern, and the entire epithelium of the esophagus was not stained by Lugol iodine spraying. Based on six biopsies randomly performed, a poorly differentiated adenocarcinoma was diagnosed. Since the M-NBI pattern and the histology were completely different, EMR-c was performed to obtain large bloc specimens for a more detailed diagnosis. The pathological findings revealed extensive Paget's cells infiltration into the epithelium and multifocal invasion from the mucosa to the submucosal layer with adenocarcinoma. In conclusion, a large bloc specimen by EMR-c might be more useful than a small biopsy for an accurate diagnosis of the rare esophageal Paget's disease.

Oval mucosal opening bloc biopsy after incision and widening by ring thread traction for submucosal tumor.

Gastric submucosal tumors (SMTs) less than 2 cm are generally considered benign neoplasms, and endoscopic observation is recommended, but SMTs over 2 cm, 40% of which are gastrointestinal stromal tumors (GISTs), have malignant potential. Although the Japanese Guidelines for GIST recommend partial surgical resection for GIST over 2 cm with malignant potential as well as en bloc large tissue sample to obtain appropriate and large specimens of SMTs, several reports have been published on tissue sampling of SMTs, such as with endoscopic ultrasound sound fine needle aspiration, submucosal tunneling bloc biopsy, and the combination of bite biopsy and endoscopic mucosal resection. Because a simpler, more accurate method is needed for appropriate treatment, we developed oval mucosal opening bloc biopsy after incision and widening by ring thread traction for submucosal tumor (OMOB) approach. OMOB was simple and enabled us to obtain large samples under direct procedure view as well as allowed us to restore to original mucosa.

Comparison of Retroflexed and Forward Views for Colorectal Endoscopic Submucosal Dissection.

BACKGROUND: The use of a retroflexed view exposes the entire tumor surface, which is obscured in the forward view, and contributes to complete tumor resection when combined with forward views. However, the efficacy and safety of using the retroflexed view for colorectal endoscopic submucosal dissection (ESD) are poorly understood. METHODS: In this study, we assessed the efficacy and safety of the retroflexed view in colorectal ESD. From April 2009 to December 2013, 130 colorectal tumors were examined in 128 patients treated with ESD. A total of 119 patients with a mean tumor size of 27.2 mm were enrolled in the study, and these patients were assigned to undergo colorectal ESD with or without a retroflexed view. RESULTS: The use of retroflexion was successful in 84.2% of patients. There were no perforations in the study and no complications related to the use of retroflexed views. The mean procedure time was 103.6 ± 55.8 min in the retroflexed group, as compared with 108.0 ± 66.5 min in the forward view group. The mean procedure time for resecting tumors >40 mm was significantly shorter in the retroflexed group relative to the forward group. Additionally, the mean dissection speed per unit area was significantly faster in the retroflexed group, as compared with the forward group. CONCLUSIONS: Retroflexed views can be used to remove lesions >40 mm and shorten procedure times. Retroflexion may also contribute to an improved en bloc resection rate.

Molecular analysis of specificity of anti-nonylphenol polyethoxylate single-chain antibody fragments by grafting and designed point mutations.

Alkylphenol polyethoxylates and alkylphenols are widely distributed contaminants in the environment. Two anti-alkylphenol polyethoxylate monoclonal antibodies MOF3-139 and AP-14 were established to measure these chemicals by enzyme immunoassays in previous studies. Interestingly, these two monoclonal antibodies showed different specificity; AP-14 cross-reacts with nonylphenoxyacetic acid and nonylphenol, whereas MOF3-139 does not. To understand the molecular basis of the difference in specificity, single-chain Fv (scFv) antibodies derived from the monoclonal antibodies were each produced in Escherichia coli cells and characterized in competitive enzyme-linked immunosorbent assay. The scFv antibodies exhibited comparable reactivity profiles to the derived parent monoclonal antibodies. It was found that the VH domain of AP-14 play an important role in the cross-reaction when specificity tests were performed using variable domain-swapped scFv antibodies. An experiment using complementarity-determining region (CDR)-grafted scFv antibodies revealed that CDR1 and CDR2 of AP-14 are involved in the cross-reaction to nonylphenoxyacetic acid and nonylphenol, respectively. Site-directed mutagenesis was introduced in both regions and the assay revealed that 33rd Thr and 35th His in VH domain of AP-14 were highly involved in the cross-reaction with nonylphenoxyacetic acid and that 33rd Thr, 57th Asp, and 59th Glu were involved in the cross-reaction with nonylphenol. The findings herein would contribute to the antibody engineering for specificity modification and to the generation of an alkylphenol-specific recombinant antibody by antibody engineering.

Validation of a method for predicting the precision, limit of detection and range of quantitation in competitive ELISA.

The mathematical model for predicting the precision, limit of detection (LOD) and range of quantitation (ROQ) in a competitive enzyme-linked immunosorbent assay (ELISA) proposed by Hayashi et al. (Anal. Chem., 2004, 76, 1295) was validated. The model describes the relative standard deviation (RSD) of concentration estimates by the RSDs of pipetting volumes of analyte, enzyme-conjugated antigen, antibody and substrate solutions, and the standard deviation (SD) of inherent absorbances between the wells in an ELISA plate. For 6 kinds of direct competitive ELISA kits, the LOD and ROQ predicted by the model agreed well with those obtained by experiments with real samples. It was also confirmed that the model is applicable to the prediction of uncertainty that depends on the pipetting error of the viscous antiserum solution. The model was demonstrated to be useful for estimating the LOD and ROQ of competitive ELISA.

Evaluation of commercial immunoassays for the detection of estrogens in water by comparison with high-performance liquid chromatography tandem mass spectrometry HPLC-MS/MS (QqQ).

In this work four different commercially available enzyme-linked immunosorbent assays (ELISA) (from Japan EnviroChemicals, Ltd., Tokyo, Japan) were evaluated in terms of performance for the rapid screening of estrogens in different water matrices, including natural and spiked samples from urban wastewater, river water and ground water. All four test kits are based on monoclonal antibodies. The compounds detected by these immunoassays are (1) 17-beta-estradiol, (2) estrone, (3) 17-alpha-ethynyl estradiol and (4) estrogens in general, with high recognition properties for 17-beta-estradiol, estrone and estriol. Standards were prepared in water containing 10% (v/v) methanol. The IC50 (corresponding to the 50% of the effective concentration) values, the dynamic ranges, and the limits of detection of the ELISA kits were 0.060-0.304 microg/L, 0.05-5 microg/L and 0.05 microg/L, respectively. All samples were extracted by solid-phase extraction (SPE) beforehand, and the evaluation was carried out by comparing the results obtained by ELISA with those obtained by HPLC-MS/MS using a triple quadrupole (QqQ) instrument. In addition, two different solid-phase extraction procedures were carried out and compared. Except for moderate overestimation in the results observed with the ELISA kits in the analysis of complex wastewater samples, the results obtained using all of the tested techniques were generally in very good agreement.

Piezoelectric immunosensor for bisphenol A based on signal enhancing step with 2-methacrolyloxyethyl phosphorylcholine polymeric nanoparticle.

An immunoassay in which BPA competed with a BPA-horseradish peroxidase conjugate for binding to anti-BPA antibodies, coupled to a piezoelectric (PZ) immunosensor, was able to detect 0.1 ng mL(-1) BPA. To enhance the sensitivity of the assay, we tested nanoparticles approximately 200 nm in diameter, coupled to anti-BPA antibodies, to increase the mass change on the surface of the immunosensor and thereby increase the frequency shift detected. This second step, using nanoparticles coated with anti-BPA antibodies, improved the sensitivity of the assay by approximately eight times at BPA concentrations below 10 ng mL(-1). Field emission-scanning electron microscopy (FE-SEM) showed that polymeric 2-methacrolyloxyethyl phosphorylcholine (MPC) nanoparticles coupled to antibodies remained monodisperse on the surface of the immunosensor and therefore produced stable signals in the immunosensors. Since the frequency shift detected in the assay mainly originated from the mass change on the surface of the PZ crystal, the colloidal stability of the antibody-conjugated particles used in the enhancement step played an extremely important role in achieving a stable and highly sensitive signal.

Development of enzyme-linked immunosorbent assay for detection of alkylphenol polyethoxylates and their biodegradation products.

An enzyme-linked immunosorbent assay (ELISA) was developed for the quantitative analysis of alkylphenol polyethoxylates (APnEOs) and their biodegradation products. To generate a specific monoclonal antibody (mAb) for the ELISA, hybridoma cells were produced by the fusion of mouse myeloma cells and spleen cells from mice immunized with nonylphenol polyethoxylate (NPnEO) derivatives coupled to bovine serum albumin. The developed ELISA showed the detection limits of 16 and 30 microg/L NP10EO when 10% and 60% (v/v) methanol solutions were used as assay diluent. The mAb was shown to be specific to APnEOs and their metabolites, such as short-ethoxy-chain APnEOs and alkylphenoxy carboxylic acids, except for nonylphenol. Moreover, no response was observed with non-APnEO surfactants as well as other compounds structurally similar to APnEOs. The percentage river water recoveries of 85-118% were obtained for 10 microg/L NP10EO fortification after preconcentration by C18 solid-phase extraction. The ELISA was also validated by comparing it with high-performance liquid chromatography for the analysis of APnEOs and their metabolites in river samples; the correlation coefficient between the values obtained by these assays was 0.96.

Rapid and sensitive detection of 17beta-estradiol in environmental water using automated immunoassay system with bacterial magnetic particles.

A fully automated immunoassay of 17beta-estradiol (E2) was performed using anti-E2 monoclonal antibody immobilized on bacterial magnetic particles (AntiE2-BMPs) and alkaline phosphatase-conjugated E2 (ALP-E2). E2 concentration in environmental water samples was evaluated by decrease in luminescence based on competitive reaction. A linear correlation between the luminescence intensity and E2 concentration was obtained between 0.5 and 5 ppb. The minimum detectable concentration of E2 was 20 ppt. All measurement steps were done within 0.5 h. The analysis of environmental water samples by a commercially available ELISA kit and the BMP-based immunoassay gave good correlation plots with a correlation efficient of 0.992. These results suggest that the fully automated system using the BMP-based immunoassay has some advantages in the high rapidity and sensitivity of the measurement. This system will enable us to determine low E2 concentrations without sample condensation.