Thermal tissue damage caused by new endoscope model due to light absorption.

BACKGROUND AND AIM: Bright endoscopic light sources improve the visibility of the intestinal mucosa. A newly launched endoscopic system developed by Olympus Corporation (Tokyo, Japan) in 2020 required modification to prevent heat-induced tissue damage, which reportedly occurs during magnifying chromoendoscopy. We investigated the mechanism of this phenomenon by evaluating the rise in temperature of stained and unstained porcine mucosa using the new and previous endoscopic systems. METHODS: Surface temperatures of stained (India ink, 0.05% crystal violet, 0.5% methylene blue, or 0.2% indigo carmine) and unstained porcine mucosa were evaluated using infrared imaging after contact with the new endoscopic system before it was modified (system-EVIS X1; scope-GIF-EZ1500) and compared with a previous endoscopic system (system-EVIS EXERAIII; scope-GIF-H190). We performed histological analysis of the porcine mucosa stained with 0.05% crystal violet after contact with the new endoscope to evaluate the degree of tissue damage. RESULTS: Surface temperatures remained < 40°C when the new endoscope was in contact with the unstained mucosa. However, the maximum surface temperature rose to > 70°C when the new endoscope was in contact with the stained mucosa (stained other than indigo carmine). Histological analysis revealed cavity formation in porcine epithelium stained with crystal violet where the endoscope made contact for ≥ 5 s . Using the previous endoscope, the maximum surface temperature of stained mucosa remained below approximately 60°C, and the surface temperature of the unstained mucosa remained below 30°C. CONCLUSIONS: Heat transfer by light absorption could cause heat-induced tissue damage during magnifying chromoendoscopy using the new endoscope.

Repeated talaporfin sodium photodynamic therapy for esophageal cancer: safety and efficacy.

BACKGROUND: Talaporfin sodium photodynamic therapy (tPDT) is an effective salvage treatment for local failure after chemoradiotherapy for esophageal cancer. Repeated tPDT could also be indicated for local recurrence or residue after the first salvage tPDT. However, the safety and efficacy of repeated tPDT have not been elucidated. METHODS: We reviewed 52 patients with esophageal cancer who were treated with the first tPDT at Kyoto University Hospital between October 2015 and April 2020. RESULTS: Among 52 patients, repeated tPDT after the first tPDT was indicated for 13 patients (25%), of which six had residual tumor, four had local recurrence after complete response (CR) after the first tPDT at the primary site, and six had metachronous lesion. The total session of repeated tPDT was 25; 16 were for primary sites and nine were for metachronous sites. Among them, six patients (46.2%) achieved local (L)-CR and nine lesions (56.3%) achieved lesion L-CR. By session, 10 sessions (40%) achieved L-CR. There were no severe adverse events except for one patient; this patient showed grade 3 esophageal stenosis and perforation after the third tPDT on the same lesion that was previously treated with porfimer sodium photodynamic therapy four times. CONCLUSION: Repeated tPDT could be an effective and safe treatment for local failure even after salvage tPDT for esophageal cancer.

Factors affecting dilation force in balloon dilation of severe esophageal strictures: an experiment using an artificial stricture model.

BACKGROUND: The multidiameter balloon catheter is used widely for severe esophageal stricture dilation. However, the relationships between inflation pressure, balloon size, and radial dilation force at the stricture site have not been examined fully. METHODS: We performed an experiment using phantom models to investigate the relationships between inflation pressure, balloon size, and radial dilation force. The balloon dilation procedure was performed for each stricture model using three sizes of balloon: 10-11-12, 12-13.5-15, and 15-16.5-18 mm. RESULTS: A positive association between inflation pressure and dilation force was observed for each balloon size. In balloons inflated by targeting the same diameter, the dilation force was higher for smaller balloons than for larger balloons. An inverse association between stricture size and dilation force was observed in the 12-13.5-15 mm balloon (3 vs 5 mm, P = .002; 5 vs 7 mm, P < .001). CONCLUSIONS: We found relationships between inflation pressure, balloon size, severity of strictures, and dilation force. To perform safe and effective esophageal balloon dilation, the inflation pressure and balloon size should be selected after considering the stricture size and target diameter.

Endoscopic laryngo-pharyngeal surgery for superficial laryngo-pharyngeal cancer.

BACKGROUND AND STUDY AIMS: Narrow band imaging (NBI) combined with magnifying endoscopy enables us to detect superficial laryngo-pharyngeal cancers, which are difficult to detect by standard endoscopy. Endoscopic laryngo-pharyngeal surgery (ELPS) is a technique developed to treat such lesions and the purpose of this study is to evaluate the usefulness of ELPS for superficial laryngo-pharyngeal cancer. PATIENTS AND METHODS: Seventy five consecutive patients with 104 fresh superficial laryngo-pharyngeal cancers are included in this study. Under general anesthesia, a specially-designed curved laryngoscope was inserted to create a working space in the pharyngeal lumen. A magnifying endoscope was inserted transorally to visualize the field and a head & neck surgeon dissected the lesion using the combination of the orally-inserted curved grasping forceps and electrosurgical needle knife in both hands. The safely, functional outcomes, and oncologic outcomes of ELPS were evaluated retrospectively. RESULTS: Median operation time per lesion was 35 min. Post-operative bleeding occurred in 3 cases and temporal subcutaneous emphysema occurred in 10 cases. No vocal fold impairment occurred after surgery. The median fasting period was 2 days and all patients except one have a normal diet with no limitations. Local recurrence occurred in 1 case, and the 3-year overall survival rate and the 3-year disease specific survival rate was 90% and 100%, respectively. CONCLUSIONS: ELPS is a hybrid of head and neck surgery and gastrointestinal endoscopic treatment, and enjoys the merit of both procedures. ELPS makes it possible to perform minimally-invasive surgery, preserving both the swallowing and phonation functions.

Diagnostic accuracy of endoscopic features of pediatric acute gastrointestinal graft-versus-host disease.

BACKGROUND AND AIM: Acute gastrointestinal graft-versus-host disease (GI-GVHD) is a major cause of morbidity and mortality after hematopoietic stem cell transplantation (HSCT). There are very few studies on specific endoscopic findings in pediatric acute GI-GVHD. The aim of this retrospective case-control study was to elucidate the characteristic endoscopic findings in pediatric acute GI-GVHD that improve the diagnostic accuracy of endoscopy. METHODS: All consecutive patients under 18 years of age who underwent allogeneic HSCT in Kyoto University Hospital from May 2003 to October 2014 were identified retrospectively. Patients who underwent GI endoscopy as a result of sustained GI symptoms were identified. Intestinal villous patterns were evaluated by magnification endoscopy with the water-immersion technique. The patients were diagnosed with acute GI-GVHD and non-GVHD on the basis of biopsy histology. Endoscopic findings of the two groups were compared. RESULTS: Of the 171 patients who underwent HSCT, 30 underwent GI endoscopy. Of these, 17 and nine were diagnosed with acute GI-GVHD and non-GVHD, respectively. Compared with non-GVHD, acute GI-GVHD was associated significantly more often with short blunt villi in the duodenum (P = 0.013), variable defect villi and short blunt villi in the ileum (P = 0.009 and 0.035, respectively), and edema, erosion, and tortoiseshell-like mucosae in the colon (P = 0.017, 0.023, and 0.017, respectively). CONCLUSION: Pediatric acute GI-GVHD was associated with several characteristic features on magnifying endoscopy with the water-immersion technique. These features will be useful for endoscopic diagnosis of pediatric acute GI-GVHD.

Prior use of immunomodulatory drugs improves the clinical outcome of endoscopic balloon dilation for intestinal stricture in patients with Crohn's disease.

BACKGROUND: Endoscopic balloon dilation is a promising procedure to improve symptoms of intestinal stricture in patients with Crohn's disease (CD). However, the long-term efficacy of endoscopic balloon dilation combined with immunomodulatory drugs remains unclear. The aim of the present study is to investigate whether prior use of immunomodulatory drugs affects the clinical outcome of endoscopic balloon dilation for intestinal stricture in CD. PATIENTS AND METHODS: Between January 2004 and December 2011, 83 dilations were carried out in 25 patients with CD. Median follow-up period was 46 months. Patients were categorized into two groups based on their medications at the first endoscopic balloon dilation: early immunomodulatory drug-induction group (early IM-induction group) in which patients were already treated with immunomodulatory drugs before the dilation; and post-immunomodulatory drug-induction group (post-IM-induction group) in which patients were not yet treated withimmunomodulatory drugs before dilation. We compared the long-term cumulative non-surgical rate and the mean number of dilation procedures per patient between early and post-IM-induction groups to clarify the influence of prior use of immunomodulatory drugs on the clinical outcome of endoscopic balloon dilation. RESULTS: There was a significant difference in the mean number of dilation procedures per patient between the early IM-induction and post-IM-induction groups (P = 0.04), although no significant difference in the cumulative non-surgical rate was observed between the two groups (P = 0.14). CONCLUSION: Prior use of immunomodulatory drugs may improve the clinical outcome of endoscopic balloon dilation for intestinal stricture in CD.

Biostimulant red seaweed (Gracilaria tenuistipitata var. liui) extracts spray improves yield and drought tolerance in soybean.

Drought has a deleterious impact on the growth, physiology, and yield of various plants, including soybean. Seaweed extracts are rich in various bioactive compounds, including antioxidants, and can be used as biostimulants for improving yield and alleviating the adverse effect of drought stress. The purpose of this study was to evaluate the effect of soybean growth and yield with different concentrations (0.0%, 5.0%, and 10.0% v/v) of water extracts of the red seaweed Gracilaria tenuistipitata var. liui under well-watered (80% of field capacity (FC) and drought (40% of FC)) conditions. Drought stress decreased soybean grain yield by 45.58% compared to well-watered circumstances but increased the water saturation deficit by 37.87%. It also decreased leaf water, chlorophyll content, plant height, and the fresh weight of the leaf, stem, and petiole. Drought stress decreased soybean grain yield by 45.58% compared to well-watered circumstances but increased the water saturation deficit by 37.87%. It also decreased leaf water, chlorophyll content, plant height, and the fresh weight of the leaf, stem, and petiole. Under both drought and well-watered situations, foliar application of seaweed extracts dramatically improved soybean growth and production. Under drought and well-watered situations, 10.0% seaweed extract increased grain yield by 54.87% and 23.97%, respectively in comparison to untreated plants. The results of this study suggest that red seaweed extracts from Gracilaria tenuistipitata var. liui may be used as a biostimulant to improve soybean yield and drought tolerance in the presence of insufficient water. However, the actual mechanisms behind these improvements need to be further investigated in field conditions.

Effects of free immunoglobulin light chains on viral myocarditis.

RATIONALE: In recent work, we have demonstrated a crucial role of mast cells in the development of viral myocarditis. Viral infection could lead to increased synthesis of free immunoglobulin light chains (FLC) and our earlier work showed that FLC can trigger mast cell activation. OBJECTIVE: We studied the possible involvement of FLC in the pathogenesis of viral myocarditis, and therapeutic effects of FLC using an animal model of viral myocarditis. METHODS AND RESULTS: DBA/2 mice were inoculated intraperitoneally with encephalomyocarditis (EMC) virus. Serum levels and concentrations in the heart of kappa FLC on day 14 in mice inoculated with EMC virus were significantly increased compared with controls. Myocardial viral concentration was significantly inhibited, the area of myocardial lesions was smaller in mice treated with kappa or lambda FLC, and survival of mice given FLC significantly improved. In contrast, an FLC antagonist deteriorated myocarditis. kappa and lambda FLC chains inhibited EMC viral replication in human amnion cells in vitro. lambda FLC significantly increased the gene expression of interleukin-10 in the heart which was previously shown to improve viral myocarditis when given exogenously. FLC also tended to increase the gene expressions of interferon-alpha and -gamma in the heart mice. CONCLUSIONS: FLC have antiviral and antiinflammatory effects and improved viral myocarditis in mice. FLC may be promising agents for the treatment of viral myocarditis.

A novel endoscopic imaging system for quantitative evaluation of colonic mucosal inflammation in patients with quiescent ulcerative colitis.

Background and study aims Mucosal healing (MH) is associated with clinical outcome in ulcerative colitis (UC) patients. In most clinical trials, a Mayo endoscopic subscore (MES) of 0 or 1 is defined as MH. However, several recent studies have reported that clinical outcome is different between UC patients with MES 0 and those with MES 1. In addition, the MES is subjective and may differ among endoscopists. Therefore, a repeatable and objective scoring system is required to distinguish MES 0 from MES 1, even in clinically quiescent UC. Here, we assessed the usefulness of new image-enhancing endoscopic technology, the i-scan TE-c, to quantitatively evaluate colonic inflammation in patients with quiescent UC. Methods We retrospectively reviewed the data from 52 UC patients in clinical remission who had undergone routine colonoscopy with standard white light. The white-light images were reassessed using the new system, and the degree of colonic mucosal inflammation was quantified according to the MAGIC (Mucosal Analysis of Inflammatory Gravity by i-scan TE-c Image) score. We used the i-scan TE-c system to investigate the association among the MAGIC score, MES, and histologic activity (Geboes score). Results The MAGIC score was significantly higher in the MES 1 group than in the MES 0 group ( P  = 0.0034). The MAGIC score significantly correlated with the Geboes score ( P  = 0.015). Conclusions Our novel image-enhancing endoscopic system was useful for objective and quantitative evaluation of MH in patients with quiescent UC. Further clinical studies using this imaging system are required to confirm its clinical benefit for the management of UC patients.

Mast cells play a critical role in the pathogenesis of viral myocarditis.

BACKGROUND: Mast cells are powerful producers of multiple cytokines and chemical mediators playing a pivotal role in the pathogenesis of various cardiovascular diseases. We examined the role of mast cells in murine models of heart failure due to viral myocarditis, using 2 strains of mast cell-deficient mice. METHODS AND RESULTS: Two strains of mast cell-deficient mice, WBB6F1-Kit(W)/Kit(W-v) (W/W(V)) and WCB6F1-Kitl(Sl)/Kitl(Sl-d) (Sl/Sl(d)), were inoculated with 10 plaque-forming units of the encephalomyocarditis virus intraperitoneally. On day 14 after inoculation, survival of W/W(V) mice was significantly higher than that of their control littermates (77% versus 31%; P=0.03; n=13). On histological examination on day 7, myocardial necrosis and cellular infiltration were significantly less pronounced in W/W(V) and Sl/Sl(d) mice than in their control littermates (area of infiltration, 7.6+/-3.5% versus 29.3+/-15.6%; P=0.002; area of necrosis, 7.6+/-3.5% versus 30.0+/-17.2%; P=0.003; n=10). Histological examination showed more severe changes in mast cell-reconstituted than in -nonreconstituted W/W(V) and Sl/Sl(d) mice. The gene expressions of mast cell proteases were upregulated in the acute phase of viral myocarditis and rose further in the subacute phase of heart failure. Their activation coincided with the development of myocardial necrosis and fibrosis and correlated with the upregulation of gene expression of matrix metalloproteinase-9. The histamine H1-receptor antagonist bepotastine improved encephalomyocarditis viral myocarditis. CONCLUSIONS: These observations suggest that mast cells participate in the acute inflammatory reaction and the onset of ventricular remodeling associated with acute viral myocarditis and that the inhibition of their function may be therapeutic in this disease.

French maritime pine bark extract inhibits viral replication and prevents development of viral myocarditis.

BACKGROUND: French maritime pine bark extract (Pycnogenol) revealed diverse anti-inflammatory actions by an inhibition of NF-kappaB-dependent gene expression. The aim of this study was to determine whether Pycnogenol had a beneficial effect on viral myocarditis in mice. METHODS AND MATERIALS: Four-week-old inbred male DBA/2 mice were inoculated intraperitoneally with 10 plaque-forming units (pfu) of the encephalomyocarditis (EMC) virus. Pycnogenol was administered orally at a dose of 1 or 10 mg/kg per day for the histologic study, and 10 or 100 mg/kg for the gene expression study, beginning on the day of viral inoculation. RESULTS: The area of myocardial infiltration and necrosis on day 7 was significantly smaller in the hearts of mice treated with Pycnogenol 10 mg/kg (16.2 +/- 8.9% and 19.2 +/- 9.7%, respectively, n = 10, mean +/- SEM) compared with controls (27.6 +/- 15.0% and 30.1 +/- 15.7%, respectively, n = 10, P < .05). There was a nonsignificant trend for less myocardial infiltration in the Pycnogenol 1 mg/kg group. Myocardial virus concentration on day 7 was 8.4 +/- 0.3 x 10(3) pfu/mg in mice treated with 1 mg/kg of Pycnogenol, and 2.7 +/- 0.6 x 10(4) pfu/mg in control mice, and the difference was statistically significant (P < .05). Gene expressions of tumor necrosis factor, type-I procollagen, stem cell factor, and mast cell tryptase were significantly suppressed in the hearts of mice treated with Pycnogenol 100 mg/kg. CONCLUSIONS: These results suggest that Pycnogenol exerts its beneficial effects on viral myocarditis by decreasing virus replication, and by suppressing expression of pro-inflammatory cytokines, genes related to cardiac remodeling, and mast cell-related genes in the hearts of mice.

Carbon-polydimethylsiloxane-based integratable optical technology for spectroscopic analysis.

A polydimethylsiloxane (PDMS)-based optical system has been demonstrated. To suppress intense background radiation due to multiple internal scatting in a transparent material, a composite structure of a carbon-PDMS compound and PDMS was proposed. The index matching of the real part of the refractive index can suppress internal scattering, and an absorption of 99-99.7% was attained by using carbon micro particles and carbon nano tubes. The black-PDMS light channel functions as a light filter for straight pass, and an optical density of 5 was obtained by bending the filter.

Tricho-hepato-enteric syndrome with novel SKIV2L gene mutations: A case report.

RATIONALE: Tricho-hepato-enteric syndrome (THES) is a rare disorder caused by mutations in the TTC37 or SKIV2L genes and characterized by chronic diarrhea, liver disease, hair abnormalities, and high mortality in early childhood due to severe infection or liver cirrhosis. PATIENT CONCERNS: The patient is the second child of three siblings born to non-consanguineous healthy Japanese parents. She had intrauterine growth retardation and was delivered at 33 weeks of gestation due to placental abruption. She presented with watery diarrhea, elevated levels of liver enzymes, multiple episodes of recurrent bacterial infection, and mild mental retardation. She had facial dysmorphism, including prominent forehead and hypertelorism, and had woolly hair without trichorrhexis nodosa. DIAGNOSIS: Clinical features led to consideration of THES. Novel compound heterozygous nonsense mutations, c.1420G>T (p.Q474*) and c.3262G>T (p.E1088*), in the SKIV2L gene were identified in the patient, and decreased levels of SKIV2L protein expression were revealed by flow cytometry and confirmed by western blot analysis using patient peripheral blood mononuclear cells (PBMCs). INTERVENTIONS: Total parenteral nutrition was required from day 30 to day 100. Trimethoprim-sulfamethoxazole prophylaxis was started at the age of 7 years after multiple episodes of bacterial pneumonia and otitis media. OUTCOMES: Chronic diarrhea persisted for more than 10 years, but the symptoms gradually improved with age. At the age of 13 years, she started a normal diet in combination with oral nutritional supplementation and her height and weight were just below the 3rd percentile for healthy individuals. She developed secondary sex characteristics, and menarche occurred at the age of 12 years. Facial dysmorphism, including prominent forehead and hypertelorism, and woolly hair without trichorrhexis nodosa became noticeable as she matured. LESSONS: Physicians must be aware of THES when they encounter a patient with infantile diarrhea, hair abnormalities, immune deficiency, mental retardation, and liver disease. Moreover, flow cytometric detection of SKIV2L protein in PBMCs may facilitate early diagnosis.

Differences of image enhancement in image-enhanced endoscopy: narrow band imaging versus flexible spectral imaging color enhancement.

BACKGROUND: Narrow band imaging (NBI) can emphasize images of the surface microvasculature of lesions, because the central wavelengths of the NBI filter are 415 and 540 nm and these wavelengths are well absorbed by hemoglobin. Flexible spectral imaging color enhancement (FICE) increases the contrast in depictions of mucosal lesions. However, quantitative evaluation of the image enhancement shown by NBI and FICE has not been reported. The aim of this study was to measure and compare the degrees of image enhancement in NBI and FICE. METHODS: We compared the visibility of human blood diluted with distilled water between that shown by white-light imaging (WLI) and that shown by NBI or FICE. One milliliter of human blood was plated onto a 12-well transparent plastic plate to set up doubling dilutions, from 1/2 to 1/2(23). High-definition endoscopes were used for each imaging method. A total of 11 endoscopists independently evaluated the visibility of the diluted blood. The median dilution was defined as the limit of visibility in each image. RESULTS: NBI enabled clearer visualization of the presence of blood compared with conventional WLI. NBI recognized blood contamination up to a 1/2(14) dilution, whereas conventional WLI recognized blood contamination up to a 1/2(11) dilution. In contrast, FICE did not improve the visualization of diluted blood and recognized blood contamination up to a 1/2(10) dilution. CONCLUSIONS: NBI more effectively enhanced images of diluted blood compared to conventional WLI, while FICE did not improve the visualization of the diluted blood. These data suggest the usefulness of NBI for the early detection of gastrointestinal neoplasia, which is accompanied by abundant neovascularization.

The impact of adenosine pharmacologic stress combined with low-level exercise in patients undergoing myocardial perfusion imaging (BIWAKO adenosine-Ex trial).

BACKGROUND: The combination of adenosine infusion with low-level exercise has become a common approach for inducing stress during stress myocardial perfusion imaging (MPI). We investigated stress MPI performed by combined low-level exercise and adenosine infusion. This combined protocol can decrease adverse reactions and reduce the effect of scattered rays from the liver. METHODS AND RESULTS: Subjects were clinically referred for a 53-min rest-stress Tc-99m Sestamibi MPI procedure using BIWAKO PROTOCOL. Ninety-eight patients (44.5%) underwent adenosine infusion with ergometer exercise testing and 122 patients (55.5%) underwent adenosine infusion without exercise testing. We evaluated the liver/heart (L/H) uptake ratio, background activity in the upper mediastinum, and adverse reactions. RESULTS: The L/H ratio and background activity were lower in the adenosine-exercise group than in the adenosine-non-exercise group (1.8 ± 0.54 vs. 2.1 ± 0.62, P < 0.0056; 43.1 ± 12.2 vs. 61.5 ± 15.4, P < 0.0001). The adenosine-exercise group had fewer adverse reactions than the adenosine-non-exercise group (11.2 vs. 19.7%). All of the adverse reactions were minor, with the exception of severe back pain in one case. The incidence of adverse reactions in our study was lower than that in previous studies for unknown reason. CONCLUSION: Adenosine infusion in combination with low-level exercise seems to result in higher-quality images and fewer adverse reactions than adenosine infusion without exercise. The combined protocol decreases adverse reactions and improves the quality of myocardial perfusion images by decreasing background activity.

New protocol of myocardial SPECT imaging with technetium-99m sestamibi for reducing the time interval between rest and adenosine stress phases.

We have developed a new protocol of myocardial perfusion-gated single-photon emission computed tomography (SPECT), by use of technetium-99m sestamibi (MIBI), in which SPECT imaging at rest followed by SPECT imaging after adenosine with low level ergometer stress can be conducted by use of the Monzen position within a shortened total testing time of 1 h or less. The study group consisted of 137 patients who underwent this new imaging protocol. The diagnostic quality of the images was as good as that of images obtained with the conventional method (30-60 min after the injection of MIBI). The SPECT image quality for the 137 patients was evaluated, and the percentages of images rated as excellent, good, fair, and poor were 65.3, 27.4, 5.8, and 1.5% for the rest image, and 68.2, 21.9, 8.4, and 1.5% for the stress image, respectively. The shortened total testing time reduced the physical and mental burden on the patient compared with that of conventional myocardial perfusion imaging. Because this technique allows us to perform rest and stress myocardial imaging within a short period, it is expected to be very useful in the clinical setting.