10 research outputs found
Allicin-induced Activation of Peristalsis in Rat Ileum Depends on Bicarbonate Ion Transport
Background: Allicin, a main component of garlic, possesses various beneficial pharmacological and therapeutic properties, including anticarcinogenic, bactericidal, and intestinal regulatory effects. Although it is known to regulate intestinal contraction and ion transport, the direct correlation between these two activities remains unclear. Hence, this study investigated the correlation between the allicin-induced activation of peristalsis and ion transport in the rat intestine.Methods: In this work, we used ileal segments of nine-week-old Sprague-Dawley rats, which have more active spontaneous contractions than colonic segments. To examine the role of allicin in regulating electrogenic ion transport in the rat ileum, we measured the transmural potential difference (ΔPD) with an Ussing chamber system. To study intestinal peristalsis, we performed an experiment to measure the velocity of the movement of an artificial pellet during intestinal peristalsis by recording videos with an overhead camera. SPSS software was used for data analysis and P-values<0.05 was considered as significant.Results: A dose of 100 μM allicin induced a significant positive ΔPD when administered to the serosal side of the ileum (P-value for 100 μM vs. 30 μM=0.038). Removing chloride ions from the incubation solution did not significantly change the allicin-induced positive ΔPD. Removing bicarbonate ions from the incubating solution completely suppressed the allicin-induced increase in ΔPD. Allicin-induced pellet movement in the ileum significantly diminished when bicarbonate ions were removed from the incubation solution. Allicin-induced ileal spontaneous peristalsis was completely suppressed in the presence of an inhibitor of a bicarbonate ion transporter (30 μM 5-nitro-2-(3-phenylpropylamine) benzoic acid).Conclusion: The present study on ion transport suggests that allicin mainly induces the ileal electrogenic secretion of bicarbonate ions in the rat ileum. In addition, a study of intestinal peristalsis suggested that allicin-induced ileal peristalsis depends on the extracellular bicarbonate ions electrogenically secreted in the ileum
Artificial Production and Natural Breeding of the Endangered Frog Species Odorrana ishikawae, with Special Reference to Fauna Conservation in the Laboratory
Odorrana ishikawae is listed as a class IB endangered species in the IUCN Red List and is protected by law in both Okinawa and Kagoshima Prefectures, Japan. Here, in an effort to help effectively preserve the genetic diversity of this endangered species in the laboratory, we tested a farming technique involving the artificial breeding of frogs, and also promoted natural breeding in the laboratory. Field-caught male/female pairs of the Amami and Okinawa Island populations were artificially bred using an artificial insemination method in the 2004, 2006, and 2008 breeding seasons (March to April). Although fewer than 50% of the inseminated eggs achieved metamorphosis, approximately 500, 300, and 250 offspring from the three respective trials are currently being raised in the laboratory. During the 2009 and 2010 breeding seasons, second-generation offspring were produced by the natural mating activities of the first offspring derived from the two artificial matings in 2004. The findings and the methods presented here appear to be applicable to the temporary protection of genetic diversity of local populations in which the number of individuals has decreased or the environmental conditions have worsened to levels that frogs are unable to survive by themselves
Induction of Thymic Stromal Lymphopoietin Production by Nonanoic Acid and Exacerbation of Allergic Inflammation in Mice
Background: Thymic stromal lymphopoietin (TSLP) plays critical roles in the induction and exacerbation of allergic diseases. We tested various chemicals in the environment and found that xylene and 1,2,4-trimethylbenzene induced the production of TSLP in vivo. These findings prompted us to search for additional chemicals that induce TSLP production. In this study, we examined whether fatty acids could induce the production of TSLP in vivo and exacerbate allergic inflammation.
Methods: Various fatty acids and related compounds were painted on the ear lobes of mice and the amount of TSLP in the homogenate of ear lobe tissue was determined. The effects of nonanoic acid on allergic inflammation were also examined.
Results: Octanoic acid, nonanoic acid, and decanoic acid markedly induced TSLP production, while a medium-chain aldehyde and alcohol showed only weak activity. Nonanoic acid induced the production of TSLP with a maximum at 24 h. TSLP production was even observed in nonanoic acid-treated C3H/HeJ mice that lacked functional toll-like receptor 4. The aryl hydrocarbon receptor agonist β-naphthoflavone did not induce TSLP production. Nonanoic acid promoted sensitization to ovalbumin, resulting in an enhancement in the cutaneous anaphylactic response. In addition, painting of nonanoic acid after the sensitization augmented picryl chloride-induced thickening of the ear, which was reversed in TSLP receptor-deficient mice.
Conclusions: Nonanoic acid and certain fatty acids induced TSLP production, resulting in the exacerbation of allergic inflammation. We propose that TSLP-inducing chemical compounds such as nonanoic acid be recognized as chemical allergo-accelerators
National trends in the outcomes of subarachnoid haemorrhage and the prognostic influence of stroke centre capability in Japan: retrospective cohort study
Objectives To examine the national, 6-year trends in in-hospital clinical outcomes of patients with subarachnoid haemorrhage (SAH) who underwent clipping or coiling and the prognostic influence of temporal trends in the Comprehensive Stroke Center (CSC) capabilities on patient outcomes in Japan.Design Retrospective study.Setting Six hundred and thirty-one primary care institutions in Japan.Participants Forty-five thousand and eleven patients with SAH who were urgently hospitalised, identified using the J-ASPECT Diagnosis Procedure Combination database.Primary and secondary outcome measures Annual number of patients with SAH who remained untreated, or who received clipping or coiling, in-hospital mortality and poor functional outcomes (modified Rankin Scale: 3–6) at discharge. Each CSC was assessed using a validated scoring system (CSC score: 1–25 points).Results In the overall cohort, in-hospital mortality decreased (year for trend, OR (95% CI): 0.97 (0.96 to 0.99)), while the proportion of poor functional outcomes remained unchanged (1.00 (0.98 to 1.02)). The proportion of patients who underwent clipping gradually decreased from 46.6% to 38.5%, while that of those who received coiling and those left untreated gradually increased from 16.9% to 22.6% and 35.4% to 38%, respectively. In-hospital mortality of coiled (0.94 (0.89 to 0.98)) and untreated (0.93 (0.90 to 0.96)) patients decreased, whereas that of clipped patients remained stable. CSC score improvement was associated with increased use of coiling (per 1-point increase, 1.14 (1.08 to 1.20)) but not with short-term patient outcomes regardless of treatment modality.Conclusions The 6-year trends indicated lower in-hospital mortality for patients with SAH (attributable to better outcomes), increased use of coiling and multidisciplinary care for untreated patients. Further increasing CSC capabilities may improve overall outcomes, mainly by increasing the use of coiling. Additional studies are necessary to determine the effect of confounders such as aneurysm complexity on outcomes of clipped patients in the modern endovascular era