Stimulation of hydrogen peroxide production by drinking water contaminants in HL-60 cells sensitized by retinoic acid

Chemical carcinogens, such as chloroform and trichloroethylene, are present in drinking water in Japan. As these contaminants are believed to have a role in carcinogenesis, we examined if chloroform and trichloroethylene, as well as methylene chloride, xylene, benzene, and ethanol, have the ability to generate hydrogen peroxide (H₂O₂) in human polymorphonuclear leukocytes (PMN) and human leukemia (HL-60) cells. Methylene chloride, benzene, xylene, trichloroethylene, and ethanol did not increase cellular H₂O₂: production as measured by flow cytometry nor as observed by confocal laser microscopy. In PMN and RAuntreated HL-60 cells chloroform did not significantly affect H₂O₂ levels. However, in HL-60 cells sensitized by pretreatment of 10 nM retinoic acid (RA) for 12 h, chloroform induced a significant increase in H₂O₂, but the increase induced by trichloroethylene was not significant. The observed increase in fluorescence was confirmed using a confocal laser microscope. These results indicate that chloroform and trichloroethylene may stimulate H₂O₂ production in HL60 cells sensitized by pretreatment of RA. Our method may be useful to test if weak stimulants can stimulate intracellular H₂O₂ production.     

An economic evaluation of Japanese telemedicine, focusing on teleradiology and telepathology

We collected information by postal survey from 622 medical institutions reported to be using telemedicine in Japan. The questionnaire asked about willingness to pay (WTP) for telemedicine and willingness to undertake (WTU) it. The Kernel Estimation Method was used to obtain WTP for teleradiology (4379 yen), telepathology (9526 yen), teleconferencing (2084 yen) and teleconsultation (633 yen). The estimated WTU were teleradiology (3875 yen), telepathology (17,918 yen), teleconferencing (3230 yen) and teleconsultation (3643 yen). These values are larger than the current charges that customers actually pay or providers receive. Multiplying these values by the number of medical institutions that had implemented telemedicine allows the total annual benefits of telemedicine to be estimated, e.g. for teleradiology, the annual benefit in terms of WTP and WTU (millions of yen per year) were 140.20 and 1101.75, respectively. Based on the results of the survey, specific policy measures to promote telemedicine further include improvement of quality and reimbursement.     

Dietary intake of seaweed and minerals and prevalence of allergic rhinitis in Japanese pregnant females: baseline data from the Osaka Maternal and Child Health Study

PURPOSE: It may be worthwhile to assess the possible protective effect of the traditional Japanese diet on allergic disorders. This cross-sectional study investigated the relationship between dietary intake of seaweed, vegetables, fruit, antioxidants, fiber, and minerals and the prevalence of allergic rhinitis. METHODS: Study subjects were 1002 Japanese pregnant women. Allergic rhinitis (including cedar pollinosis) was defined as present if subjects had received drug treatment at some point during the previous 12 months. Information on dietary factors was collected by using a self-administered diet history questionnaire. RESULTS: Seaweed intake was associated independently with a decreased prevalence of allergic rhinitis. Significant inverse dose-response relationships were found between calcium and phosphorus intake and allergic rhinitis prevalence. There also was a tendency for an inverse association between magnesium consumption and allergic rhinitis. Additional adjustment for calcium or magnesium intake apparently did not influence the inverse association with seaweed consumption. Consumption of vegetables, fruit, vitamins C and E, fiber, and zinc showed no association with allergic rhinitis, whereas a significant positive relationship was observed between beta-carotene intake and allergic rhinitis. CONCLUSIONS: High dietary intake of seaweed, calcium, magnesium, and phosphorus may be associated with a decreased prevalence of allergic rhinitis.     

Comparison of Symptomatic Vasospasm after Surgical Clipping and Endovascular Coiling

Vasospasm, initial neurological damage, rebleeding, and periprocedural complications are associated prognostic factors for clinical outcomes after aneurysmal subarachnoid hemorrhage (SAH). In this study, factors related to delayed ischemic neurological deficit (DIND) are evaluated using data from our institute for the last 18 years. Data from 2001 to 2018 of patients with aneurysmal SAH who underwent surgical clipping (SC) or endovascular coiling (EC) within 7 days of onset were retrospectively analyzed. Cases of mortality within 5 days after treatment were excluded. Multivariate analysis was used to identify the risk factors for DIND. In total, 840 cases of SAH were assessed; among these cases, 384 (45.7%) and 456 (54.3%) were treated with SC and EC, respectively. The frequency of DIND in the EC group was significantly less than that in the SC group (11.8% vs. 17.7%; p = 0.016). In the results of multivariate analysis, internal carotid artery (ICA) aneurysm and hemorrhagic complications were the risk factors for DIND. Cilostazol administration and EC were significant factors for vasospasm prevention after aneurysmal SAH (odds ratio of ICA aneurysm: 1.59, hemorrhagic complications: 1.76, SC: 1.51, and cilostazol administration: 0.51, respectively). Cilostazol administration was also a significant factor in patients who were treated with EC. ICA aneurysm, treatment strategy, hemorrhagic complications, and cilostazol administration were associated with DIND. Oral administration of cilostazol and avoiding hemorrhagic complications were effective in DIND prevention. If both treatments are available for ruptured aneurysms, clinicians should choose EC on the basis of its ability to prevent DIND.     

Effect of Host Structure on Optical Freedericksz Transition in Dye-Doped Liquid Crystals

The optical Freedericksz transition (OFT) can reversibly control the molecular orientation of liquid crystals (LCs) only by light irradiation, leading to the development of all-optical devices, such as smart windows. In particular, oligothiophene-doped LCs show the highly sensitive OFT due to the interaction between dyes and an optical-electric field. However, the sensitivity is still low for the application to optical devices. It is necessary to understand the factors in LCs affecting the OFT behavior to reduce the sensitivity. In this study, we investigated the effect of the host LC structure on the OFT in oligothiophene-doped LCs. The threshold light intensity for the OFT in trifluorinated LCs was 42% lower than that in LCs without fluorine substituents. This result contributes to the material design for the low-threshold optical devices utilizing the OFT of dye-doped LCs.     

Predictive factors for surgical complications of laparoscopy-assisted distal gastrectomy for gastric cancer

Background  Some studies have found high incidences of intraoperative and postoperative complications for patients with gastric cancer. To determine the predictive factors for the surgical complications of laparoscopic gastric surgery, surgical outcomes were evaluated. Methods  Between April 2002 and December 2007, 152 patients with preoperatively diagnosed early gastric cancer who underwent laparoscopy-assisted distal gastrectomy (LADG) were enrolled. Visceral (VFA) and subcutaneous fat areas (SFA) were assessed by Fat Scan software. The predictive factors for surgical complications of LADG were evaluated by univariate and logistic regression analyses. Results  Of 152 patients, conversion to open surgery due to uncontrollable bleeding was observed in nine male patients, and postoperative complications were detected in seven male and one female patient (four anastomotic leakage, two intraabdominal abscess, one pancreatic fistula, and one lymphorrhea). High body mass index (BMI) and high VFA independently predicted conversion to open surgery and postoperative complications. VFA was significantly higher, operation time was longer, blood loss was greater, and SFA was lower in male than in female patients, whereas no significant difference was observed in BMI between male and female patients. Conclusions  High BMI and high VFA can predict technical difficulties during laparoscopic gastric surgery and postoperative complications. Particularly, LADG should be performed cautiously to prevent surgical complications for male patients with high VFA. Predictive impact of VFA should be further determined in a larger set of patients.     

Therapeutic action of 5-HT3 receptor antagonists targeting peritoneal macrophages in post-operative ileus

Background and Purpose

Post-operative ileus (POI) is induced by intestinal inflammation. Here, we aimed to clarify the effects of 5-HT₃ receptor antagonists against POI.

Experimental Approach

We administered three 5-HT₃ receptor antagonists, ondansetron, tropisetron and palonosetron, to a mouse model of POI induced by surgical intestinal manipulation (IM). Immunohistochemistry, intestinal transit, inflammatory mediator mRNA expression and 5-HT content were measured. In some experiments, 5-HT₃A receptor null mice were used.

Key Results

Three 5-HT₃ receptor antagonists reduced IM-induced infiltration of inflammatory CD68-positive macrophages and myeloperoxidase-stained neutrophils. Ondansetron exhibited no anti-inflammatory actions in 5-HT₃A receptor null mice. Ondansetron inhibited expression of the chemokine CCL2, IL-1β, IL-6, TNF-α and iNOS mRNAs up-regulated by IM, and also ameliorated the delayed gastrointestinal transit. Peritoneal macrophages, but not most infiltrating monocyte-derived macrophages, expressed 5-HT₃ receptors. IM stimulation increased the 5-HT content of peritoneal lavage fluid, which up-regulated mRNA expression of proinflammatory cytokines in peritoneal macrophages. Immunohistochemical localization of 5-HT₃ receptors suggests that ondansetron suppressed expression of these mRNAs in activated peritoneal macrophages, adhering to the serosal region of the inflamed intestinal wall.

Conclusion and Implications

5-HT₃ receptor antagonists were anti-inflammatory, mainly targeting peritoneal macrophages expressing these receptors. They also restored the delayed gastrointestinal transit by IM. 5-HT₃ receptor antagonists should be therapeutically useful agents against POI.     

Comprehensive genetic characterization of rectal cancer in a large cohort of Japanese patients: differences according to tumor location

Journal of Gastroenterology - In clinical practice, rectal cancer (RC) is classified according to tumor location. However, RC’s genetic characteristics according to tumor location remain...