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871.
The problem of controlling invasive species has emerged as a global issue. In response to invasive species threats, governments often propose eradication. This article challenges the eradication view by studying optimal strategies for controlling invasive species in a simple dynamic model. The analysis mainly focuses on deriving policy implications of catchability in a situation where a series of controlling actions incurs operational costs that derive from the fact that catchability depends on the current stock size of invasive species. We analytically demonstrate that the optimal policy changes drastically, depending on the sensitivity of catchability in response to a change in the stock size, as well as on the initial stock. If the sensitivity of catchability is sufficiently high, the constant escapement policy with some interior target level is optimal. In contrast, if the sensitivity of catchability is sufficiently low, there could exist a threshold of the initial stock which differentiates the optimal action between immediate eradication and giving-up without any control. In the intermediate range, immediate eradication, giving-up without any control, or more complex policies may be optimal. Numerical analysis is employed to present economic intuitions and insights in both analytically tractable and intractable cases. 相似文献
872.
Yasuko Watanabe Manabu Igarashi Yuhei Shimoyama Tohru Yamamori Mikinori Kuwabara Osamu Inanami 《Biochemical and biophysical research communications》2010,394(3):522-38545
To explore Cu(II) ion coordination by His186 in the C-terminal domain of full-length prion protein (moPrP), we utilized the magnetic dipolar interaction between a paramagnetic metal, Cu(II) ion, and a spin probe introduced in the neighborhood of the postulated binding site by the spin labeling technique (SDSL technique). Six moPrP mutants, moPrP(D143C), moPrP(Y148C), moPrP(E151C), moPrP(Y156C), moPrP(T189C), and moPrP(Y156C,H186A), were reacted with a methane thiosulfonate spin probe and a nitroxide residue (R1) was created in the binding site of each one. Line broadening of the ESR spectra was induced in the presence of Cu(II) ions in moPrP(Y148R1), moPrP(Y151R1), moPrP(Y156R1), and moPrP(T189R1) but not moPrP(D143R1). This line broadening indicated the presence of electron-electron dipolar interaction between Cu(II) and the nitroxide spin probe, suggesting that each interspin distance was within 20 Å. The interspin distance ranges between Cu(II) and the spin probes of moPrP(Y148R1), moPrP(Y151R1), moPrP(Y156R1), and moPrP(T189R1) were estimated to be 12.1 Å, 18.1 Å, 10.7 Å, and 8.4 Å, respectively. In moPrP(Y156R1,H186A), line broadening between Cu(II) and the spin probe was not observed. These results suggest that a novel Cu(II) binding site is involved in His186 in the Helix2 region of the C-terminal domain of moPrPC. 相似文献
873.
874.
Takakazu Kaneko Kiwamu Minamisawa Tsuyoshi Isawa Hiroki Nakatsukasa Hisayuki Mitsui Yasuyuki Kawaharada Yasukazu Nakamura Akiko Watanabe Kumiko Kawashima Akiko Ono Yoshimi Shimizu Chika Takahashi Chiharu Minami Tsunakazu Fujishiro Mitsuyo Kohara Midori Katoh Naomi Nakazaki Shinobu Nakayama Manabu Yamada Satoshi Tabata Shusei Sato 《DNA research》2010,17(1):37-50
We determined the nucleotide sequence of the entire genome of a diazotrophic endophyte, Azospirillum sp. B510. Strain B510 is an endophytic bacterium isolated from stems of rice plants (Oryza sativa cv. Nipponbare). The genome of B510 consisted of a single chromosome (3 311 395 bp) and six plasmids, designated as pAB510a (1 455 109 bp), pAB510b (723 779 bp), pAB510c (681 723 bp), pAB510d (628 837 bp), pAB510e (537 299 bp), and pAB510f (261 596 bp). The chromosome bears 2893 potential protein-encoding genes, two sets of rRNA gene clusters (rrns), and 45 tRNA genes representing 37 tRNA species. The genomes of the six plasmids contained a total of 3416 protein-encoding genes, seven sets of rrns, and 34 tRNAs representing 19 tRNA species. Eight genes for plasmid-specific tRNA species are located on either pAB510a or pAB510d. Two out of eight genomic islands are inserted in the plasmids, pAB510b and pAB510e, and one of the islands is inserted into trnfM-CAU in the rrn located on pAB510e. Genes other than the nif gene cluster that are involved in N2 fixation and are homologues of Bradyrhizobium japonicum USDA110 include fixABCX, fixNOQP, fixHIS, fixG, and fixLJK. Three putative plant hormone-related genes encoding tryptophan 2-monooxytenase (iaaM) and indole-3-acetaldehyde hydrolase (iaaH), which are involved in IAA biosynthesis, and ACC deaminase (acdS), which reduces ethylene levels, were identified. Multiple gene-clusters for tripartite ATP-independent periplasmic-transport systems and a diverse set of malic enzymes were identified, suggesting that B510 utilizes C4-dicarboxylate during its symbiotic relationship with the host plant. 相似文献
875.
Yuhko Suzuki Takeshi Nakamura Masaharu Tokoro Tomiteru Togano Manabu Ohsaka Mika Kohri Yasuyoshi Hirata Koji Miyazaki Mikio Danbara Ryouichi Horie Ikuo Miura Keisuke Sunakawa Masaaki Higashihara 《Parasitology international》2010,59(3):487-489
An 88-year-old Japanese woman was referred to our hospital due to a one-month history of face edema, aphagia, shortness of breath, and skin rush over almost her entire skin. She had no abdominal symptoms. Her peripheral blood count showed a white blood cell (WBC) count of 27.1 × 109/L with 82.1% eosinophils. Serum non-specific Immunoglobulin E was within a normal range. Soluble interleukin-2 receptor was elevated to 4200 U/mL. At first, her eosinophil count was so high that we suspected she had an eosinophilic leukemia or hypereosinophilic syndrome. After admission, cysts of Giardia duodenalis (G. duodenalis) were detected in the patient's feces by microscopic analysis, then she was diagnosed with giardiasis, and 750 mg per day of metronidazole was administered for seven days. Her WBC count decreased to 6.0 × 109/L with 10% eosinophils, and her systemic symptoms improved. At that time her serum IL-5 was within a normal range. A few months later, the patient again complained of skin rush, and G. duodenalis was once again found in her feces. Her serum IL-5 was elevated to 751 pg/mL. Metronidazole was administered for two weeks, and her eosinophil count decreased. G. duodenalis is a protozoan parasite, and it is one of the most common waterborne transmission gastrointestinal parasites in the world. G. duodenalis rarely causes hypereosinophilia. To our knowledge, this is the first case report of giardiasis with extreme hypereosinophilia and severe systemic symptoms. 相似文献
876.
877.
Sabrina Pankey Hiroshi Sunada Tetsuro Horikoshi Manabu Sakakibara 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2010,180(8):1205-1211
Dermal photoreceptors in the pond snail Lymnaea stagnalis mediate the whole-body withdrawal response, including pneumostome closure, elicited by a shadow passing over the pneumostome
area. The pneumostome closure response is part of the defense reaction in Lymnaea. The shadow or ‘light-off’ stimulus elicits activity in a higher order interneuron, RPeD11, which has a major role in mediating
defensive withdrawal behavior elicited by noxious or threatening stimuli. Here, we tested our hypothesis that cyclic nucleotide-gated
(CNG) channels are involved in the dermal photoreceptor-mediated transduction of the shadow stimulus. The response to the
shadow stimulus recorded in RPeD11 was abolished by 500 μM cis-diltiazem, which blocks cGMP-activated conductance of CNG channels. On the other hand, the shadow response elicited in RPeD11
was not blocked by 2-amino ethyldiphenyl borate (2-APB), a transient receptor potential (TRP) channel blocker. Consistent
with the electrophysiologic data, cis-diltiazem blocked the shadow-evoked withdrawal response, whereas 2-APB did not block the withdrawal response evoked by the
shadow stimulus in intact freely behaving Lymnaea. Together, these findings support the hypothesis that the second messenger in dermal photoreceptors involves CNG and not
TRP channels. 相似文献
878.
Kimura S Maruyama J Watanabe T Ito Y Arioka M Kitamoto K 《Fungal genetics and biology : FG & B》2010,47(12):1044-1054
Properly folded proteins destined for secretion exit through a specific subdomain of the endoplasmic reticulum (ER) known as transitional ER (tER) sites or ER exit sites (ERES). While such proteins in filamentous fungi localize at the hyphal tips overlapping the Spitzenk?rper, the distribution of misfolded proteins remains unknown. In the present study, we analyzed the distribution of mutant protein as well as ER and tER sites visualized by expression of AoClxA and AoSec13 fused with fluorescent protein, respectively, in the filamentous fungus Aspergillus oryzae. Discrete tER subdomains were visualized as the punctate dots of AoSec13 overlapping or associated with AoClxA distribution. Both ER and tER sites were concentrated near hyphal tips and formed apical gradients. Interestingly, while the expression of wild-type α-amylase fusion protein (AmyB-mDsRed) showed its localization coinciding with the Spitzenk?rper, a disulfide bond-deletion in AmyB causing its misfolding resulted in its accumulation in the subapical and basal ER, creating a reciprocal gradient to the tER sites. Furthermore, the reciprocal gradient enabled a clear distinction between the tER sites and the mutant AmyB accumulation sites near the apex. Based on these findings, we conclude that A. oryzae accumulates aberrant proteins toward basal hyphae while maintaining polarized tER sites for secretion of properly folded proteins at the hyphal tip. 相似文献
879.
Nagai K Takikawa O Kawakami N Fukao M Soma T Oda A Nishiya T Hayashi M Lu L Nakano M Kajita E Fujita H Miwa S 《Archives of biochemistry and biophysics》2006,452(1):29-37
Acetylcarnitine exerts therapeutic effects on some neurological disorders including Alzheimer's disease. OCTN2 is known as a transporter for acetylcarnitine, but its expression in the brain is very low. To examine a brain-specific transporter for acetylcarnitine, we screened a rat brain cDNA library by hybridization using a DNA probe conserved among an OCTN family. A cDNA homologous to OCTN2 cDNA was isolated. The cDNA encoded a novel 146-amino acid protein with one putative transmembrane domain. The mRNA was expressed not only in rat brain but also in some other tissues. The novel protein was localized in endoplasmic reticulum when expressed in COS-7 cells but exhibited no transport activity for acetylcarnitine. However, when co-expressed with OCTN2, it enhanced the OCTN2-mediated transport by about twofold. The enhancement was accompanied by an increase in the levels of mRNA and protein. When OCTN2 was expressed in Xenopus oocytes by injection of its cRNA, its transport activity was enhanced by co-expression of the novel protein. These data suggest that the novel protein increases OCTN2 by stabilizing the mRNA in endoplasmic reticulum. The protein may be an up-regulator of OCTN2 and is tentatively designated cartregulin. 相似文献
880.
Unoki H Bujo H Shibasaki M Saito Y 《Biochemical and biophysical research communications》2006,350(2):392-398
Using preadipocyte implantation methods, we recently demonstrated that adipocytes in the visceral area change their function, as the expression of tumor necrosis factor-alpha (TNF-alpha) increases, thereby causing insulin resistance. In order to clarify the mechanism for changes in the function of adipocytes in visceral area, we examined the mRNA expression profiles in visceral fat tissue specimens. Four weeks after cell implantation, we performed a microarray analysis using the RNA of fat tissue specimens implanted either with 3T3-L1 cells or PBS alone. Sixty-three genes were thus isolated and the expression of matrix metalloproteinase-3 (MMP-3) mRNA was found to dramatically increase in the fat tissue specimens. The neutralization of MMP-3 protein inhibited adipogenesis and the free fatty acid-induced TNF-alpha secretion in 3T3-L1 adipocytes. These results suggest a potential role of MMP-3, which promotes the TNF-alpha secretion, thus contributing to the disturbance of the functions in the adipocytes which accumulate in the visceral area. 相似文献