Transcriptome analysis of hagfish leukocytes: a framework for understanding the immune system of jawless fishes

Jawless fishes occupy a critical phylogenetic position in understanding the origin of the adaptive immune system. Here, we performed large-scale expressed sequence tag analysis of leukocytes isolated from the inshore hagfish Eptatretus burgeri. Although we found many immunity-related genes such as those involved in lymphocyte or hematopoietic cell signaling and development as well as cytokine and cytokine receptor genes, MHC molecules or antigen receptors were not identified. We characterized two hagfish cDNAs that closely resembled mammalian proteins with essential roles in adaptive immunity, one encoding a GATA3-like molecule and another encoding a Bruton's tyrosine kinase (Btk)-like molecule. The GATA3-like gene of hagfish was equidistant from GATA3 and GATA2 in jawed vertebrates. Similarly, the hagfish Btk-like molecule was not Btk itself, but qualified as a pre-duplicated form of Btk and Bmx in jawed vertebrates. In total, our work provides circumstantial evidence that adaptive immunity is unique to jawed vertebrates.     

Irritant-induced cyclooxygenase-2 is involved in the defense mechanism of the gastric mucosa in mice

Background. Endogenous and exogenous prostaglandins (PGs) have been shown to contribute to reducing the gastric injury caused by irritants given subse-quently. The aim of this study was to clarify whether cyclooxygenase-2 (COX-2) protein induced by pretreatment was involved in the prevention of subsequent ethanol-caused gastric injury in mice. Methods. Mice were pretreated with acidified ethanol or saline and then COX-2 protein expression in the stomach was immunohistochemically determined every 8 h. Mice were administered 95% ethanol 24 h after the acidified ethanol pretreatment, and gastric mucosal damage was evaluated macroscopically and histologically. The effects of NS-398 or indomethacin on the 95% ethanol-caused damage were also examined. Results. Acidified ethanol pretreatment induced COX-2 protein expression in lamina propria macrophages of the gastric mucosa, with a peak level 24 h after the pretreatment. The 95% ethanol treatment caused gastric mucosal damage. The degree of the damage was not different between mice pretreated with acidified ethanol and those pretreated with saline. However, NS-398 aggravated the ethanol-caused damage only in mice pretreated with acidified ethanol, while indomethacin aggravated the damage, evaluated histologically, irrespective of the pretreatment. Conclusions. Pretreatment-induced COX-2, in addition to COX-1, seemed to be involved in the defense mechanism through minimizing the damage caused by a subsequent irritant. Received: October 16, 2000 / Accepted: September 14, 2001     

Suppressive effect of intragastric nutrients infusion on insulin release from perfused rat pancreas

Using the isolated and perfused rat pancreas preparations, we examined whether or not the direct transmission of signals from the gastro-duodenum to the pancreatic islets is existent. Pancreases were isolated en bloc with stomach and the proximal portion of duodenum and were perfused without recirculation. After perfusion with 5.5mM glucose in the perfusate for 40 minutes, 1 ml solution of the following nutrients (0.9% and 9% NaCl, 5% and 50% glucose, 5% and 50% fructose) was respectively infused into the stomach. And ten minutes after the infusion, the pancreas was perfused with 16.7 mM glucose for 20 minutes. Although the glucose-induced insulin release was similar to controls in the pancreas with intragastric infusion of 0.9% NaCl, 5% glucose, and 5% fructose, it was significantly lowered in the pancreas with intragastric infusion of 9% NaCl, 50% glucose, and 50% fructose. These results indicate that there is a direct transmission of some signals from the gastro-duodenum to the pancreatic islets through intragastric high osmolarity.     

Temperature changes caused by the difference in the distance between the ultrasound transducer and bone during 1?mhz and 3?mhz continuous ultrasound: a phantom study

[Purpose] This study aimed to use a thermograph to observe temperature changes caused by different distances between an ultrasound transducer and bone during 1 MHz and 3 MHz continuous ultrasound emission on a phantom. [Materials and Methods] We observed the distribution of temperature elevations on a phantom consisting of pig ribs and tissue-mimicking material. One megahertz and 3 MHz ultrasound were delivered at 2.0 W/cm² for 5 minutes. To record the temperature changes on the phantom, we took a screenshot of the thermograph with a digital camera every 20 seconds. [Results] With 1 MHz ultrasound at the distances of 2 and 3 cm, the temperature elevation near the bone was higher than that near the transducer. However, with 3 MHz ultrasound, the temperature elevation was higher near the transducer rather than near the bone. At this point, we consider that there is a possibility of heat injury to internal organs in spite of there being no elevation of skin temperature. [Conclusion] When performing ultrasonic therapy, not only should the frequency be taken into consideration, but also the influence of the absorption coefficient and the reflection of the tissue. We visually confirmed the thermal ultrasound effect by thermography. Special attention to the temperature elevation of the internal organs is necessary to avoid injuries.Key words: Ultrasound, Thermal effect, Thermography     

The varying effects of warm-water bathing therapies: partial bathing decreases exercise tolerance to levels similar to full-body bathing

[Purpose] The purpose of this study was to determine differences in postural sway and tolerance to exercise before and after full-body, forearm, and lower leg bathing in warm-water. [Subjects and Methods] Thirteen healthy, young adult males were subjected to full-body, forearm, and lower leg bathing at 41 °C for 10 minutes. [Results] The 2-point discrimination sense value and total trajectory length significantly decreased after bathing. [Conclusion] In summary, we found that warm-water bathing sharpens plantar sensation, and thus may help to prevent falls in the elderly. Even partial forearm and lower leg bathing increased exercise tolerance to levels similar to full-body bathing.Key words: Warm-water bathing, Static balance, Exercise test     

Neonatal exposure to MK‐801 reduces mRNA expression of mGlu3 receptors in the medial prefrontal cortex of adolescent rats

Schizophrenia is considered as a “neurodegenerative” and “neurodevelopmental” disorder, the pathophysiology of which may include hypofunction of the N‐methyl‐d ‐aspartate receptor (NMDA‐R) or subsequent pathways. Accordingly, administration of NMDA‐R antagonists to rodents during the perinatal period may emulate some core pathophysiological aspects of schizophrenia. The effect of 4‐day (postnatal day; PD 7–10) administration of MK‐801, a selective NMDA‐R antagonist, on gene expression in the medial prefrontal cortex (mPFC), hippocampus, and amygdala was evaluated using quantitative polymerase chain reaction methods. Specifically, we sought to determine whether genes related to Glu transmissions, for example those encoding for NMDA‐Rs, metabotropic Glu receptors (mGluRs), or Glu transporters, were altered by neonatal treatment with MK‐801. Model rats showed downregulation of the mGluR3 subtype in the mPFC around puberty, especially at PD 35 in response to MK‐801 or during ontogenesis without pharmacological manipulations. Genes encoding for other mGluRs subtypes, that is NMDA‐Rs and Glu transporters, were not affected by the neonatal insult. These results suggest that NMDA‐R antagonism in the early course of development modulates the expression of mGluR3 in mPFC around puberty. Thus, mGluR3 may serve as a potential target to prevent the onset and progression of schizophrenia. Synapse 68:202–208, 2014 . © 2014 Wiley Periodicals, Inc.