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91.
Kiyoaki Kuwasawa Hiroyuki Ai Tomoko Matsushita 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》1999,124(4):175
Previously described salines for lepidoptera did not maintain a constant heart rate for a very long. We have been successful in maintaining a normal heartbeat for many hours in a newly designed saline. This saline was also suitable for maintaining normal neuromuscular junctional potentials. The cardiac reflexes studied in larvae of Bombyx and Agrius were five types of cardiac responses induced by mechanical stimuli to sensillar setae. The cardiac responses were caused by electrical stimulation of nerves in the reflex pathways. The antidromic heartbeat was triggered even in larvae before the 5th instar by stimulation of axons in the visceral nerve arising from the frontal ganglion and terminating at the aorta, while spontaneous heartbeat reversal started to occur in wandering larvae. Other axons in the visceral nerve terminate at the rear end of the heart. Electrical stimuli to the nerves caused cardiac inhibition of the orthodromic heartbeat. Nerves extending from the visceral nerve to the alary muscles of the 2nd abdominal segment contain axons to increase the tone of the muscles. Nerves extending from the 7th abdominal ganglion to the most posterior alary muscles also contain axons to increase the tone of the muscles, and were responsible for acceleration of the antidromic and orthodromic heartbeat, respectively. 相似文献
92.
Kashiwagi Y Kawashima H Sato S Ioi H Amaha M Takekuma K Hoshika A Oshiro H Matsubayashi J Mukai K 《Microbiology and immunology》2007,51(1):53-62
We report three infants and one teenager with fatal virus-associated haemophagocytic syndrome (VAHS). Two infants were admitted to our hospital because of cardio-pulmonary arrest (CPA). The third infant was admitted to our department because of fever and liver dysfunction, and he was diagnosed as combined immunodeficiency with predominant T cell defect. The teenager was diagnosed as systemic lupus erythema (SLE) when she was 10 years old and admitted to our department because of fever and thrombocytopenia . The histological findings for the four patients' organs revealed many haemophagocytic cells . The patients were infected by Parainfluenza virus type 2 (PIV2), Enterovirus (EV), Cytomegalovirus (CMV), and Epstein-Barr virus (EBV), respectively. Their laboratory data revealed elevated levels of ferritin and IL-6, which also suggested virus-associated haemophagocytic syndrome (VAHS). Although aggressive therapies were performed in all cases, the outcome was fatal. Further investigation would be needed to clarify the mechanism of VAHS and an effective therapeutic regimen is needed. 相似文献
93.
In pursuance of economic growth and development, logging has exhausted the natural timber resource in the tropical rainforest
of Sabah, Malaysia. Realizing the forest depletion, the Sabah Forestry Department, with technical support from the German
Agency for Technical Cooperation, begun developing a management system with the intent of managing all commercial forest reserves
in a way that mimics natural processes for sustainable production of low volume, high quality, and high priced timber products
in 1989. As dictated by a forest management plan based on forest zoning, about 51,000 ha of the entire area is set aside for
log production and 4,000 ha for conservation in Deramakot Forest Reserve, Sabah, Malaysia. This Forest Management Plan has
served as the blueprint for operational work and biodiversity conservation in Deramakot to the present. A strict protection
area is set aside for biodiversity conservation within the reserve. A reduced-impact logging system is being employed for
harvesting with minimal impacts on the physical environment. Deramakot Forest Reserve was certified as “well managed” by an
international certification body, the Forest Stewardship Council, in 1997 and is the first natural forest reserve in Southeast
Asia managed in accordance with sustainable forestry principles. In addition to providing a "green premium," certification
provides easier market access, evidence of legality, multi-stakeholder participation, conservation of biodiversity and best
forest management practices, particularly reduced-impact logging techniques. Deramakot Forest Reserve is the flagship of the
Sabah Forestry Department and serves as a symbol of what can be achieved with political support and institutional commitment. 相似文献
94.
Nakamura T Yonesu K Mizuno Y Suzuki C Sakata Y Takuwa Y Nara F Satoh S 《Bioorganic & medicinal chemistry》2007,15(10):3548-3564
A series of Sodium 4-[(4-butoxyphenyl)thio]-2'-substituted-1,1'-biphenyl-3- sulfonates were identified as functional sphingosine-1-phosphate (S1P) antagonists with selectivity for the S1P(1) receptor subtype starting from chemical lead 2, which was found while screening our in-house compound library. We performed chemical modifications on each regional structure of compound 2, for example, on the three ring compartments, the benzyl substituents, and the long alkyl chain part. The introduction of a biphenyl skeletal structure and the installation of a hydroxyl group onto the terminal carbon in the side-chain region resulted in the potent derivative 35c, which showed >500-fold more potent S1P(1) inhibitory activity than lead compound 2. We report herein the synthesis and structure-activity relationships of structurally novel S1P(1) receptor antagonists. 相似文献
95.
Females of the hump earwig, Anechura harmandi, are completely consumed by their offspring at the end of their care (matriphagy). The effect of this matriphagy was assessed by manipulative experiments. Matriphagy led to a delay in the dispersal of the nymphs and an increase in their survival rate. The same results were obtained when mothers were removed and the nymphs were given sufficient food. Females separated from their offspring after larval hatching failed to produce a second clutch, and three-quarters of them did not develop their ovaries. These results suggest that the survival of nymphs and their stay in the nest are dependent on food availability and that A. harmandi females are strictly semelparous. 相似文献
96.
Hiroki Maeda Takeshi Hatta Daigo Tsubokawa Fusako Mikami Toshiyuki Nishimaki Takeshi Nakamura Makoto Matsubayashi Motoyuki Ogawa Clarissa Prazeres da Costa Naotoshi Tsuji 《Parasitology international》2018,67(5):609-611
Parasite-induced behavioral changes in their hosts favor to complete the lifecycle of parasites. Schistosome infection is also known to cause physiological changes in infected freshwater snail intermediate hosts. Here, we report, a novel phenomenon in which Schistosoma mansoni, a highly debilitating worm affecting millions of people worldwide, alters the phototropic behavior of Biomphalaria glabrata, the vector snail. S. mansoni-infection enhanced positive phototropism of vector snails and infected snails spent significantly more time in light. Possibly, these behavioral changes help the parasite to be released efficiently from the infected intermediate hosts, and to infect mammalian hosts. 相似文献
97.
Naoya Shinohara Takashi Owada Ami Tanaka Keiji Matsubayashi Tadashi Nagai Masahiro Satake 《Microbiology and immunology》2020,64(5):392-395
Hepatitis A virus (HAV) has begun to spread globally among men who have sex with men (MSM). Hepatitis E virus (HEV) also may be transmitted through sexual contact among MSM. To assess the current status of these viruses among MSM in Japan, the seroprevalence of both viruses using 503 plasma samples collected between 2009 and 2018 from human immunodeficiency virus (HIV)-positive male donors who were presumed to be mainly MSM was investigated. Our results suggested that HAV may be spreading within this population, as reported elsewhere. By contrast, the spread of HEV was confirmed only among younger HIV-positive donors. 相似文献
98.
Masao Yamasaki Tsuyoshi Shimizu Masao Miyake Yukako Miyamoto Shin-Ichiro Katsuda Hirotaka O-Ishi Tadanori Nagayama Hidefumi Waki Kiyoaki Katahira Haruyuki Wago Toshiyasu Okouchi Shunji Nagaoka Chiaki Mukai 《Biological Sciences in Space》2004,18(2):45-51
The effects of microgravity on the histological characteristics of the aortic depressor nerve, which is the afferent of the aortic baroreflex arc, were determined in 10 female adult rats. The rats were assigned for nursing neonates in the Space Shuttle Columbia or in the animal facility on the ground (NASA Neurolab, STS-90), and were housed for 16 days under microgravity in space (microg, n=5) or under one force of gravity on Earth (one-g, n=5). In the Schwann cell unit in which the axons of unmyelinated fibers are surrounded by one Schwann cell, the average number of axons per unit in the microg group was 2.1 +/- 1.6 (mean +/- SD, n=312) and significantly less than that in the one-g group (3.0 +/- 2.9, n=397, p<0.05). The proportion of unmyelinated fibers in the aortic depressor nerve in the microg group was 64.5 +/- 4.4% and significantly less than that in the one-g group (74.0 +/- 7.3%, p<0.05). These results show that there is a decrease in the number of high-threshold unmyelinated fibers in the aortic depressor nerve in adult rats flown on the Shuttle Orbiter, suggesting that the aortic baroreflex is depressed under microgravity during space flight. 相似文献
99.
Shuichi Matsuda Atsushi Funabiki Kaoru Furukawa Nozomi Komori Masanori Koike Yoshihiko Tokuji Itsuro Takamure Kiyoaki Kato 《Molecular genetics and genomics : MGG》2012,287(10):819-835
The roles of the proteins encoded by half-size adenosine triphosphate-binding cassette transporter subgroup G (ABCG) genes in abiotic stress responses are starting to be established in the dicot model Arabidopsis thaliana. In the monocot model rice, the functions of most half-size ABCG proteins in abiotic stress responses are unknown. Rcn1/OsABCG5 is an essential transporter for growth and development under abiotic stress, but its molecular function remains largely unclear. Here, we present a comprehensive overview of all 30 half-size ABCG genes in rice, including their gene structures, phylogeny, chromosome locations, and conserved motifs. Phylogenetic analysis revealed that the half-size OsABCG proteins were divided to four classes. All seven rice intronless genes, including Rcn1/OsABCG5, were in Class III, like the 12 intronless ABCG genes of Arabidopsis. The EST and FL-cDNA databases provided expression information for 25 OsABCG genes. Semi-quantitative and quantitative RT-PCR analyses demonstrated that seven OsABCG genes were up-regulated in seedlings, shoots or roots following treatments with abiotic stresses (6, 17, 42?°C, NaCl, or mannitol) and abscisic acid. Another 15 OsABCG genes were up-regulated under at least one of the abiotic stress conditions and other phytohormones besides abscisic acid. Hierarchical clustering analysis of gene expression profiles showed that expression of the OsABCG genes could be classified into four clusters. The Rcn1/OsABCG5 cluster was up-regulated by abscisic acid and included OsABCG2, 3, 13, and 27. The present study will provide a useful reference for further functional analysis of the ABCGs in monocots. 相似文献
100.