超音波画像を用いた筋膜リリース後の筋筋膜の性状の経時的変化の検討

首都大学東

Development of an animal-borne blood sample collection device and its deployment for the determination of cardiovascular and stress hormones in phocid seals

The research was supported by Bilateral Program between Japan and the United Kingdom and a Grant-in-Aid for Scientific Research (23247010) to Y. Takei and by Grant-in-Aid for challenging Exploratory Research (15K14567) to I. Suzuki from the Japan Society for the Promotion of Science. This work was also supported by funding from the U.K. Natural Environment Research Council (Grant SMRU1001).An animal-borne blood sampler with data-logging functions was developed for phocid seals, which collected two blood samples for the comparison of endocrino-logical/biochemical parameters under two different conditions. The sampler can be triggered by preset hydrostatic pressure, acceleration (descending or ascending), temperature, and time, and also man-ually by light. The sampling was reliable with 39/50 (78%) successful attempts to collect blood samples. Contamination of fluids in the tubing to the next blood sample was 1%, following the prior clearance of the tubing to a waste syringe. In captive harbor seals (Phoca vitulina), the automated blood-sampling method was less stressful than direct blood withdrawal, as evidenced by lower levels of stress hormones (P < 0.05 for ACTH and P = 0.078 for cortisol). HPLC analyses showed that both cortisol and cortisone were circu-lating in seal blood. Using the sampler, plasma levels of cardiovascular hormones, atrial natriuretic peptide (ANP), AVP, and ANG II were compared in grey seals (Halichoerus grypus), between samples collected when the animals were on land and in the water. HPLC analyses determined that [Met12] ANP (1-28) and various forms of angiotensins (ANG II, III, and IV) were circulating in seal blood. Although water immersion profoundly changes the plasma levels of cardiovascular hormones in terrestrial mammals, there were only tendencies toward an increase in ANP (P = 0.069) and a decrease in AVP (P = 0.074) in the seals. These results suggest that cardiovascular regulation in phocid seals may have undergone adaptation during evolution of the carnivore to a semiaquatic lifestyle.PostprintPeer reviewe

Aerobic and Anaerobic Biotransformation of Bile Acids by Escherichia coli (III)

The oxidation/reduction reactions of bile acids by Escherichia coli (E. coli) K-12 were examined in both Davis and brain-heart infusion (BHI) media under aerobic and anaerobic conditions. The pH in the Davis medium changed by almost the same amount, around pH 6.5?7.0 in both aerobic and anaerobic cultures, but the pH in the BHI medium was different in both cultures, that is, about pH 9.0 in the aerobic culture but only about 6.5 in the anaerobic culture. The growth curve of E. coli in the Davis medium showed a similar pattern in both conditions. Cholic acid (CA) was oxidized to 3α12α-dihydroxy-7-oxo-5β-cholanoic acid (3α12α7=O) in both cultures, but the reaction in the anaerobic culture was somewhat slower than that in the aerobic culture. On the other hand, reduction of 3α12α7=O to CA did not occur in the aerobic culture, but about 10% reduction was observed in the anaerobic culture after 4 days. These data suggest that the oxidation/reduction reaction of E. coli was oxidative in aerobic culture but reductive in anaerobic culture and these characteristics were not due to the changes in the pH of the medium. The reactions of CA and glycocholic acid to crude 7α-HSDH prepared from E. coli were examined and it was found that both free and conjugated CA as a substrate for the 7α-HSDH showed similar Km values

The Amphibious Mudskipper: A Unique Model Bridging the Gap of Central Actions of Osmoregulatory Hormones Between Terrestrial and Aquatic Vertebrates

Body fluid regulation, or osmoregulation, continues to be a major topic in comparative physiology, and teleost fishes have been the subject of intensive research. Great progress has been made in understanding the osmoregulatory mechanisms including drinking behavior in teleosts and mammals. Mudskipper gobies can bridge the gap from aquatic to terrestrial habitats by their amphibious behavior, but the studies are yet emerging. In this review, we introduce this unique teleost as a model to study osmoregulatory behaviors, particularly amphibious behaviors regulated by the central action of hormones. Regarding drinking behavior of mammals, a thirst sensation is aroused by angiotensin II (Ang II) through direct actions on the forebrain circumventricular structures, which predominantly motivates them to search for water and take it into the mouth for drinking. By contrast, aquatic teleosts can drink water that is constantly present in their mouth only by reflex swallowing, and Ang II induces swallowing by acting on the hindbrain circumventricular organ without inducing thirst. In mudskippers, however, through the loss of buccal water by swallowing, which appears to induce buccal drying on land, Ang II motivates these fishes to move to water for drinking. Thus, mudskippers revealed a unique thirst regulation by sensory detection in the buccal cavity. In addition, the neurohypophysial hormones, isotocin (IT) and vasotocin (VT), promote migration to water via IT receptors in mudskippers. VT is also dipsogenic and the neurons in the forebrain may mediate their thirst. VT regulates social behaviors as well as osmoregulation. The VT-induced migration appears to be a submissive response of subordinate mudskippers to escape from competitive and dehydrating land. Together with implications of VT in aggression, mudskippers may bridge the multiple functions of neurohypophysial hormones. Interestingly, cortisol, an important hormone for seawater adaptation and stress response in teleosts, also stimulates the migration toward water, mediated possibly via the mineralocorticoid receptor. The corticosteroid system that is responsive to external stressors can accelerate emergence of migration to alternative habitats. In this review, we suggest this unique teleost as an important model to deepen insights into the behavioral roles of these hormones in relation to osmoregulation

Biotransformation of Bile Acids by Bacteroides sp. Strain T-40 Isolated from Human Microflora

The effects of Bacteroides sp. strain T-40 isolated from human feces on the biotransformation of bile acids were examined in an anaerobic culture system. Bacteroides sp. T-40 oxidized cholic acid (CA) and chenodeoxycholic acid (CDCA) to 3α,12α-dihydroxy-7-oxo-5β-cholanoic acid and 3α-hydroxy-7-oxo-5β-cholanoic acid, and reduced these oxo-bile acids to CA and CDCA, respectively. However, the reduction activities were lower than the oxidation activities. Hyocholic acid was dehydrogenated, but to a lesser extent than CA or CDCA. On the other hand, α-muricholic acid, which has a hydroxyl group at the position of 7α, was not dehydrogenated. Glycocholic acid was converted to free 3α,12α-dihydroxy-7-oxo-5β-cholanoic acid but any glycine conjugated 7-oxo product was not detected. These data indicate that Bacteroides sp. T-40 possesses bile acid hydrolase and 7α-hydroxysteroid dehydrogenase, by which conjugated bile acids are initially deconjugated, and then undergo oxidization of the 7α-hydroxy group

Collapsin response mediator protein 1 mediates Reelin signaling in cortical neuronal migration

Collapsin response mediator protein 1 ( CRMP1) is one of the CRMP family members that mediates signal transduction of axon guidance molecules. Here, we show evidence that CRMP1 is involved in Reelin ( Reln) signaling to regulate neuronal migration in the cerebral cortex. In crmp1(-/-) mice, radial migration of cortical neurons was retarded. This phenotype was not observed in the sema3A(-/-) and crmp1(+/+); sema3A(+/+) cortices. However, CRMP1 was colocalized with disabled- 1 ( Dab1), an adaptor protein in Reln signaling. In the Reln(rl/rl) cortex, CRMP1 and Dab1 were expressed at a higher level, yet tyrosine phosphorylated at a lower level. Loss of crmp1 in a dab1 heterozygous background led to the disruption of hippocampal lamination, a Reeler- like phenotype. In addition to axon guidance, CRMP1 regulates neuronal migration by mediating Reln signaling