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1.
1. As for some other spring‐feeding moths, adult flight of Epirrita autumnata (Lepidoptera: Geometridae) occurs in late autumn. Late‐season flight is a result of a prolonged pupal period. Potential evolutionary explanations for this phenological pattern are evaluated. 2. In a laboratory rearing, there was a weak correlation between pupation date and the time of adult emergence. A substantial genetic difference in pupal period was found between two geographic populations. Adaptive evolution of eclosion time can thus be expected. 3. Metabolic costs of a prolonged pupal period were found to be moderate but still of some ecological significance. Pupal mortality is likely to form the main cost of the prolonged pupal period. 4. Mortality rates of adults, exposed in the field, showed a declining temporal trend from late summer to normal eclosion time in autumn. Lower predation pressure on adults may constitute the decisive selective advantage of late‐season flight. It is suggested that ants, not birds, were the main predators responsible for the temporal trend. 5. Egg mortality was estimated to be low; it is thus unlikely that the late adult period is selected for to reduce the time during which eggs are exposed to predators. 6. In a laboratory experiment, oviposition success was maximal at the time of actual flight peak of E. autumnata, however penalties resulting from sub‐optimal timing of oviposition remained limited. 相似文献
2.
Tatsuya Matsunami Toshihiro Suzuki Yasuo Hisa Kuniaki Takata Tetsuro Takamatsu Masahito Oyamada 《Cell communication & adhesion》2006,13(1):93-102
To elucidate the role of the spiral limbus in glucose transport in the cochlea, we analyzed the expression and localization of GLUT1, connexin26, connexin30, and occludin in the spiral limbus of the rat cochlea. GLUT1 and occludin were detected in blood vessels. GLUT1, connexin26, connexin30, and occludin were also expressed in fibrocytes just basal to the supralimbal lining cells. Connexin26 and connexin30 were present among not only these GLUT1-positive fibrocytes but also GLUT1-negative fibrocytes. In vivo glucose imaging using 6-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-6-deoxyglucose (6-NBDG, MW 342) together with Evans Blue Albumin (EBA, MW 68,000) showed that 6-NBDG was rapidly distributed throughout the spiral limbus, whereas EBA was localized only in the vessels. Moreover, the gap junctional uncoupler heptanol inhibited the distribution of 6-NBDG. These findings suggest that gap junctions play an important role in glucose transport in the spiral limbus, i.e., that gap junctions mediate glucose transport from GLUT1-positive fibrocytes to GLUT1-negative fibrocytes in the spiral limbus. 相似文献
3.
Jun Iwaki Kunio Kikuchi Yoshiaki Mizuguchi Yutaka Kawahigashi Hiroshi Yoshida Eiji Uchida Toshihiro Takizawa 《PloS one》2013,8(7)
MicroRNA miR-376c was expressed in normal intrahepatic biliary epithelial cells (HIBEpiC), but was significantly suppressed in the HuCCT1 intrahepatic cholangiocarcinoma (ICC) cell line. The biological significance of the down-regulation of miR-376c in HuCCT1 cells is unknown. We hypothesized that miR-376c could function as a tumor suppressor in these cells. To test this hypothesis, we sought the targets of miR-376c, and characterized the effect of its down-regulation on HuCCT1 cells. We performed proteomic analysis of miR-376c-overexpressing HuCCT1 cells to identify candidate targets of miR-376c, and validated these targets by 3′-UTR reporter assay. Transwell migration assays were performed to study the migratory response of HuCCT1 cells to miR-376c overexpression. Furthermore, microarrays were used to identify the signaling that were potentially involved in the miR-376c-modulated migration of HuCCT1. Finally, we assessed epigenetic changes within the potential promoter region of the miR-376c gene in these cells. Proteomic analysis and subsequent validation assays showed that growth factor receptor-bound protein 2 (GRB2) was a direct target of miR-376c. The transwell migration assay revealed that miR-376c significantly reduced epidermal growth factor (EGF)-dependent cell migration in HuCCT1 cells. DNA microarray and subsequent pathway analysis showed that interleukin 1 beta and matrix metallopeptidase 9 were possible participants in EGF-dependent migration of HuCCT1 cells. Bisulfite sequencing showed higher methylation levels of CpG sites upstream of the miR-376c gene in HuCCT1 relative to HIBEpiC cells. Combined treatment with the DNA-demethylating agent 5-aza-2′-deoxycytidine and the histone deacetylase inhibitor trichostatin A significantly upregulated the expression of miR-376c in HuCCT1 cells. We revealed that epigenetic repression of miR-376c accelerated EGF-dependent cell migration through its target GRB2 in HuCCT1 cells. These findings suggest that miR-376c functions as a tumor suppressor. Since metastasis is the major cause of death in ICC, microRNA manipulation could lead to the development of novel anti-cancer therapy strategies for ICC. 相似文献
4.
This paper defines a collection of Drosophila deletion mutations (deficiencies) that can be systematically screened for embryonic phenotypes, orphan receptor ligands, and genes affecting protein localization. It reports the results of deficiency screens we have conducted that have revealed new axon guidance phenotypes in the central nervous system and neuromuscular system and permitted a quantitative assessment of the number of potential genes involved in regulating guidance of specific motor axon branches. Deficiency “kits” that cover the genome with a minimum number of lines have been established to facilitate gene mapping. These kits cannot be systematically analyzed for phenotypes, however, since embryos homozygous for many deficiencies in these kits fail to develop due to the loss of key gene products encoded within the deficiency. To create new kits that can be screened for phenotype, we have examined the development of the nervous system in embryos homozygous for more than 700 distinct deficiency mutations. A kit of ∼400 deficiency lines for which homozygotes have a recognizable nervous system and intact body walls encompasses >80% of the genome. Here we show examples of screens of this kit for orphan receptor ligands and neuronal antigen expression. It can also be used to find genes involved in expression, patterning, and subcellular localization of any protein that can be visualized by antibody staining. A subset kit of 233 deficiency lines, for which homozygotes develop relatively normally to late stage 16, covers ∼50% of the genome. We have screened it for axon guidance phenotypes, and we present examples of new phenotypes we have identified. The subset kit can be used to screen for phenotypes affecting all embryonic organs. In the future, these deficiency kits will allow Drosophila researchers to rapidly and efficiently execute genome-wide anatomical screens that require examination of individual embryos at high magnification. 相似文献
5.
Aiyi Liu James F. Troendle Kai F. Yu Vivian W. Yuan 《Biometrical journal. Biometrische Zeitschrift》2004,46(6):760-768
We consider estimation after a group sequential test. An estimator that is unbiased or has small bias may have substantial conditional bias (Troendle and Yu, 1999, Coburger and Wassmer, 2001). In this paper we derive the conditional maximum likelihood estimators of both the primary parameter and a secondary parameter, and investigate their properties within a conditional inference framework. The method applies to both the usual and adaptive group sequential test designs. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
6.
Kai Grosch 《Journal of avian biology》2004,35(3):217-223
Although redstarts Phoenicurus phoenicurus and black redstarts P. ochruros breed in different habitats they have been found to interbreed and to produce viable and fertile offspring, which backcross to the parental species. In a dual choice experiment, I investigated the preference of black redstarts and redstarts, and F1 -hybrids for different habitat structures in an aviary. Black redstarts strongly preferred a perch type on which they could stand to a perch they had to cling to. Redstarts were less selective and used both perch types equally as long as food was offered between both perches on the ground. If food was given at one of the perches redstarts changed their preference depending on food location. Black redstarts, however, showed only a slight response. They always preferred the same perch type. Hybrids behaved like redstarts. They did not show a preference as long as food was placed on the ground. When food was offered at one of the perch sites they more often chose the one with food. Due to high phenotypic variability among individuals perch type preference overlapped between the three experimental groups. 相似文献
7.
Gisela Drews Kai Graszynski 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1987,157(3):345-353
Summary Euryhaline Crustacea living in dilute media, counterbalance the salt loss by active absorption of NaCl across the gill epithelium. To investigate the mechanisms involved in salt absorption, transeptithelial potential difference (PDte) was measured in isolated, perfused gills of the fiddler crab,Uca tangeri. The influence of some specific inhibitors of epithelial ion transport on the PDte was tested.With symmetrical conditions on both sides of the epithelium, the posterior gills ofUca tangeri showed a spontaneous PDte of +5 to +10 mV, that is an active transport potential which was positive on the bath side as referred to the hemolymph side. This potential decreased considerably after application of KCN or 2,4-dinitrophenol (DNP) to the perfusion saline.Omission of K+ from the perfusion saline or addition of ouabain led to a reversible drop of the PDte, suggesting that the absorption of Na+ and also of Cl– is driven by the (Na++K+)ATPase located in the basolateral membrane of the epithelial cells.Perfusion of the hemolymph space with saline containing diphenylamine-2-carboxylate (DPC) or the loop diuretic furosemide resulted in a decrease of the PDte.After application of amiloride to the bath saline the PDte increased. Half-maximum response to amiloride was reached at a concentration of about 10–5 mol·l–1. This suggests that one of the Na+ pathways across the apical membrane may consist of Na+ channels.Abbreviations
PD
te
transepithelial potential difference
-
DPC
diphenylamine-2-carboxylate
-
R
ps
resistance of perfusate shunt
-
R
te
transepithelial resistance
-
R
in
input resistance
-
DNP
2,4-dinitrophenol
Parts of this study have been reported at the 1st Congress of Comparative Physiology and Biochemistry, Liège 1984, and at the Vth European Colloquium on Renal Physiology, Frankfurt, 1985 相似文献
8.
Ogawa Masahiro; Kumamaru Toshihiro; Satoh Hikaru; Iwata Nobuo; Omura Takeshi; Kasai Zenzaburo; Tanaka Kunisuke 《Plant & cell physiology》1987,28(8):1517-1527
Protein body type one (PB-I) was isolated and purified fromdeveloping rice grain by a combination of sucrose density gradientcentrifugation and treatment with pepsin. SDS-PAGE analysisshowed that isolated PB-I contains several polypeptide groups,the largest having an apparent molecular size of 13 kDa andtwo smaller ones of 10 kDa and 16 kDa. The 13-kDa group wasfound to be composed of two polypeptides of slightly differentmolecular sizes, 13a (larger component) and 13b (smaller component).Most of the 13a and 13b polypeptides were shown to be largelyprolamins, although there were also some salt- and alcohol-insolublepolypeptides with an apparent molecular size of 13 kDa. It wasconcluded that PB-I is the accumulation site of rice prolamin.It was further estimated that the protein amount in PB-I accountedfor about 20% of the total protein of rice endosperm. (Received March 20, 1987; Accepted September 8, 1987) 相似文献
9.
Ulrik Pedersen-Bjergaard Lars B geskov Nielsen Kai Jensen Lars Edvinsson Inger Jansen Jes Olesen 《Peptides》1989,10(6):1147-1152
Neurokinin A (NKA), substance P (SP) and the two peptides combined (SP + NKA) were injected intracutaneously on the forearm and into the temporal muscle of healthy volunteers. Pain intensity, cutaneous wheal and flare responses and tenderness of the temporal muscle were quantitated. SP but not NKA induced cutaneous pain. This relates the algesic effect of SP to the specific N-terminal amino acid sequence of the peptide, not shared by NKA. NKA, however, potentiated the algesic effect of SP as SP + NKA induced a significantly prolonged cutaneous pain sensation. Both peptides induced wheals, but only SP induced flare. These results confirm previous studies relating wheal formation to the identical C-terminal amino acid sequence of the two peptides and flare reaction to the N-terminal part of SP. Injections into the temporal muscle did not cause pain or tenderness. 相似文献
10.
Nobutaka Fujii Akira Otaka Susumu Funakoshi Toshihiro Watanabe Hiromitsu Arai Kiyoshi Bessho Haruaki Yajima 《Journal of Protein Chemistry》1988,7(2):151-156
Treatment of a mixture of Cys(R)(O) and Cys(R) with an acid was found to generate cystine in fairly good yields, when suitable R, R, and an acid were selected. An unsymmetrical cystine peptide was prepared by treatment of a mixture of Z(OMe)-Cys(R) (0)-Ala-NH2 (R=Acm or MBzl) and Z(OMe)-Cys(MBzl)-Gly-OBzl with TFA or 1 M TFMSA/TFA.3 Oxytocin was obtained in an excellent yield by TFA treatment of the protected peptide containing Cys(Acm)(0) and Cys(MBzl). Thus, formation of the disulfide bond was found feasible at the position of Cys(R) (0).The following abbreviations are used Boc
t-butyloxycarbonyl
- Z(OMe)
p-methoxybenzyloxycarbonyl
- MBzl
p-methoxybenzyl
- Acm
acetamidomethyl
- Bzl
benzyl
- Ad
l-adamantyl
- tBu
t-butyl
- TFA
trifluoroacetic acid
- TFMSA
trifluoromethanesulfonic acid
- TMSOTf
trimethylsilyl trifluoromethane sulfonate 相似文献