The Influence of the Bright Light Exposure during Daytime on Melatonin Excreting Rate in Urine

The present study was conducted to know the effects of different light intensities exposed during daytime for several hours on melatonin excreting rate in urine and tympanic temperature. Eleven healthy female subjects were exposed to bright light of 6000 lx (Bright) or dim light of 100 lx (Dim) during daytime from 09:00 h to 13:30 h, and then the light condition was kept at 100 lx until the end of test at 14:30 h. The urinary samples were collected from 10:00 h to 14:30 h every 1.5 hours, and melatonin excreting rate in urine was measured by enzyme immunoassay. Melatonin excreting rate in urine was significantly higher in Bright than in Dim at 11:30 h and 14:30 h, and not significant but at high level at 13:00 h (p <0.07). Moreover, average tympanic temperatures were significantly lower in Bright than in Dim from 11:43 h to 14:30 h. These results showed that the bright light exposure during daytime could reduce tympanic temperature, which might result from the increase of melatonin level.     

Circadian Rhythms of Core Body Temperature and Urinary Noradrenaline Secretion under the Influence of Skin Pressure due to Foundation Garments Worn during Wakefulness

The present experiment investigated the effects of skin pressure by foundation garments (brassiere plus girdle) worn during wakefulness on the circadian rhythms of core temperature and endocrine secretion. Eight healthy females (18–23 yrs) maintaining regular sleep-wake cycles for a week prior to participation in the experiment served as participants. The experiments were performed from June to August, 1999, using a bioclimatic chamber controlled at 26.5 ± 0.2°C and 62 ± 3% RH. Ambient light intensity was controlled at 500 lx from 07:30 h to 17:30 h, 100 lx from 17:30 h to 19:30 h, 20 lx from 19:30 h to 23:30 h and there was total darkness from 23:30 h to 07:30 h. The experiment lasted for 58?h over 3 nights. The participant rose at 07:30?h in the morning of the first day and retired at 23:30 h, adhering to a set schedule for 24 h but without wearing foundation garments. From 07:30 h to 23:30 h of the second day the participant wore foundation garments but did not wear foundation garments during the sleep. Rectal and leg skin temperatures were continuously measured throughout the experiment. Urine was collected every 4 h for the analysis of catecholamines. Skin pressure applied by the foundation garments was in the range 11–17 gf/cm² at the regions of abdomen, hip, chest and back. The main results were as follows: Rectal temperature was significantly higher (p < 0.01) during wakefulness, but significantly lower (p < 0.01) during sleep with than without foundation garments. Furthermore, the amplitude of rectal temperature was larger with than without foundation garments (p < 0.033). Urinary noradrenaline was mostly lower with foundation garments throughout the day and night. The results suggest that skin pressure by foundation garments worn during wakefulness could influence the level of core body temperature and noradrenaline secretion not only during wakefulness, but also during sleep.     

Quantification of Chitinase mRNA Levels in Human and Mouse Tissues by Real-Time PCR: Species-Specific Expression of Acidic Mammalian Chitinase in Stomach Tissues

Chitinase hydrolyzes chitin, which is an N-acetyl-D-glucosamine polymer that is present in a wide range of organisms, including insects, parasites and fungi. Although mammals do not contain any endogenous chitin, humans and mice express two active chitinases, chitotriosidase (Chit1) and acidic mammalian chitinase (AMCase). Because the level of expression of these chitinases is increased in many inflammatory conditions, including Gaucher disease and mouse models of asthma, both chitinases may play important roles in the pathophysiologies of these and other diseases. We recently established a quantitative PCR system using a single standard DNA and showed that AMCase mRNA is synthesized at extraordinarily high levels in mouse stomach tissues. In this study, we applied this methodology to the quantification of chitinase mRNAs in human tissues and found that both chitinase mRNAs were widely expressed in normal human tissues. Chit1 mRNA was highly expressed in the human lung, whereas AMCase mRNA was not overexpressed in normal human stomach tissues. The levels of these mRNAs in human tissues were significantly lower than the levels of housekeeping genes. Because the AMCase expression levels were quite different between the human and mouse stomach tissues, we developed a quantitative PCR system to compare the mRNA levels between human and mouse tissues using a human-mouse hybrid standard DNA. Our analysis showed that Chit1 mRNA is expressed at similar levels in normal human and mouse lung. In contrast, the AMCase expression level in human stomach was significantly lower than that expression level observed in mouse stomach. These mRNA differences between human and mouse stomach tissues were reflecting differences in the chitinolytic activities and levels of protein expression. Thus, the expression level of the AMCase in the stomach is species-specific.     

Phylogeographic insights into the invasion history and secondary spread of the signal crayfish in Japan

Successful invasion by nonindigenous species is often attributed to high propagule pressure, yet some foreign species become widespread despite showing reduced genetic variation due to founder effects. The signal crayfish (Pacifastacus leniusculus) is one such example, where rapid spread across Japan in recent decades is believed to be the result of only three founding populations. To infer the history and explore the success of this remarkable crayfish invasion, we combined detailed phylogeographical and morphological analyses conducted in both the introduced and native ranges. We sequenced 16S mitochondrial DNA of signal crayfish from across the introduced range in Japan (537 samples, 20 sites) and the native range in western North America (700 samples, 50 sites). Because chela size is often related to aggressive behavior in crayfish, and hence, their invasion success, we also measured chela size of a subset of specimens in both introduced and native ranges. Genetic diversity of introduced signal crayfish populations was as high as that of the dominant phylogeographic group in the native range, suggesting high propagule pressure during invasion. More recently established crayfish populations in Japan that originated through secondary spread from one of the founding populations exhibit reduced genetic diversity relative to older populations, probably as a result of founder effects. However, these newer populations also show larger chela size, consistent with expectations of rapid adaptations or phenotypic responses during the invasion process. Introduced signal crayfish populations in Japan originate from multiple source populations from a wide geographic range in the native range of western North America. A combination of high genetic diversity, especially for older populations in the invasive range, and rapid adaptation to colonization, manifested as larger chela in recent invasions, likely contribute to invasion success of signal crayfish in Japan.     

uPA Attenuated LPS-induced Inflammatory Osteoclastogenesis through the Plasmin/PAR-1/Ca2+/CaMKK/AMPK Axis

Chronic inflammatory diseases, such as rheumatoid arthritis and periodontitis-caused bone destruction, results from an increase of bone-resorbing osteoclasts (OCs) induced by inflammation. However, the detailed mechanisms underlying this disorder remain unclear. We herein investigated that the effect of urokinase-type plasminogen activator (uPA) on inflammatory osteoclastogenesis induced by lipopolysaccharide (LPS), which is a potent stimulator of bone resorption in inflammatory diseases. We found that the uPA deficiency promoted inflammatory osteoclastogenesis and bone loss induced by LPS. We also showed that LPS induced the expression of uPA, and the uPA treatment attenuated the LPS-induced inflammatory osteoclastogenesis of RAW264.7 mouse monocyte/macrophage lineage cells. Additionally, we showed that the uPA-attenuated inflammatory osteoclastgenesis is associated with the activation of plasmin/protease-activated receptor (PAR)-1 axis by uPA. Moreover, we examined the mechanism underlying the effect of uPA on inflammatory osteoclastogenesis, and found that uPA/plasmin/PAR-1 activated the adenosine monophosphate-activated protein kinase (AMPK) pathway through Ca2+/calmodulin dependent protein kinase kinase (CaMKK) activation, and attenuated inflammatory osteoclastogenesis by inactivation of NF-κB in RAW264.7 cells. These data suggest that uPA attenuated inflammatory osteoclastogenesis through the plasmin/PAR-1/Ca2+/CaMKK/AMPK axis. Our findings may provide a novel therapeutic approach to bone loss caused by inflammatory diseases.     

Water entry for the black locust (<Emphasis Type="Italic">Robinia pseudoacacia</Emphasis> L.) seeds observed by dedicated micro-magnetic resonance imaging

Water entry at germination for black locust (Robinia pseudoacacia L.) seeds which are known as hard seeds with impermeable seed coat to water, was examined using micro-magnetic resonance imaging (MRI). The MRI apparatus equipped with a low-field (1 T; Tesla) permanent magnet was used, which is open access, easy maintenance, operable and transportable. The excellent point of the apparatus is that T ₁-enhancement of water signals absorbed in dry seeds against steeping free water is stronger than the apparatuses with high-field superconducting magnets, which enabled clear detection of water entry. Water hardly penetrated into the seeds for more than 8 h but approximately 60 % of seeds germinated by incubating on wet filter papers for several days. Hot water treatments above 75 °C for 3 min effectively induced water gap; scarification was 70 % at 100 °C and 75 °C, declined to 15 % at 50 °C and decreased further at room temperature. Water entered into the scarified seeds exclusively through the lens, spread along the dorsal side of the seeds and reached the hypocotyl, whereas water migrated slowly through hilum side to radicle within 3 h.     

Growth of zinnia,Italian ryegrass,and alfalfa and their remediation effects in diesel oil-contaminated soils

Abstract

Our objective in this study was to compare the growth of zinnia, Italian ryegrass, and alfalfa, and their remediation effects in oil-contaminated soils. The soils were prepared by mixing 2, 4, or 8% diesel oil by weight with soil. The plant height and dry weights of shoots and roots were highest for zinnia in the 2 and 4% oil treatments, and highest for Italian ryegrass in the 8% oil treatment. The reduction ratios in soil total petroleum hydrocarbons concentration (TPH) for 3 plants were lower in the 4 and 8% oil treatments than those in the 2% treatment. The reduction ratios for Italian ryegrass and zinnia contaminated with 2, 4, and 8% diesel oil treatments were significantly higher than those for alfalfa and the non-cultivation treatment at 45?days after sowing, and there were no significant differences in reduction ratios between Italian ryegrass and zinnia. The reduction ratio of soil TPH concentration brought about by zinnia was also comparable to that of Italian ryegrass. Therefore, we conclude that zinnia shows growth and remediation effects that are equivalent to those of Italian ryegrass, in soils contaminated with less than 8% oil.