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81.
No regulatory role for adult predation in cyclic population dynamics of the autumnal moth,Epirrita autumnata 下载免费PDF全文
1. Multiannual population cycles of geometrid moths are thought to be driven by trophic‐level interactions involving a delayed density‐dependent component. Predation on adult moths has been a little‐studied mechanism of this phenomenon. 2. Using 29 daytime and 61 night‐time predation trials in the field, we exposed living autumnal moth (Epirrita autumnata Borkhausen, Lepidoptera: Geometridae) females to their natural predators during each autumn throughout the 10‐year population cycle. 3. In our northern study location (70°N), insectivorous passerines had already migrated, and harvestman Mitopus morio Fabricius (Opiliones: Phalangiidae) was found to be the main predator of the adult moths. The predation mortality occurred mainly at night and was positively correlated with the minimum temperature measured during the predation trial. 4. Despite high annual variability in the degree of adult predation, both direct and delayed density‐dependent effects were weak and indicate that predation on adult moths in the autumn does not have any regulatory role in cyclic population dynamics of the autumnal moth in northern Fennoscandia. 相似文献
82.
JAE‐GYUN GWAG JONG‐WOOK CHUNG HUN‐KI CHUNG JEONG‐HEUI LEE KYUNG‐HO MA ANUPAM DIXIT YONG‐JIN PARK EUN‐GI CHO TAE‐SAN KIM SUK‐HA LEE 《Molecular ecology resources》2006,6(4):1132-1134
The present work reports the isolation and characterization of new polymorphic microsatellites in mung bean (Vigna radiata L.). Of 93 designed primer pairs, seven were found to amplify polymorphic microsatellite loci, which were then characterized using 34 mung bean accessions. The number of alleles ranged from two to five alleles per locus with an average of three alleles. Observed and expected heterozygosity values ranged from 0 to 0.088 and from 0.275 to 0.683, respectively. All seven loci showed significant deviations from Hardy–Weinberg equilibrium, whereas only one pairwise combination (GBssr‐MB77 and GBssr‐MB91) exhibited significant departure from linkage disequilibrium. These newly developed markers are currently being utilized for diversity assessment within the mung bean germplasm collection of the Korean Gene Bank. 相似文献
83.
Sanae Iwana Tomoya Kawazoe Hwan KI. Park Koichiro Tsuchiya Koji Ono Kazuko Yorita 《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):901-911
D-Amino acid oxidase (DAO), a potential risk factor for schizophrenia, has been proposed to be involved in the decreased glutamatergic neurotransmission in schizophrenia. Here we show the inhibitory effect of an antipsychotic drug, chlorpromazine, on human DAO, which is consistent with previous reports using porcine DAO, although human DAO was inhibited to a lesser degree (Ki = 0.7 mM) than porcine DAO. Since chlorpromazine is known to induce phototoxic or photoallergic reactions and also to be transformed into various metabolites, we examined the effects of white light-irradiated chlorpromazine on the enzymatic activity. Analytical methods including high-resolution mass spectrometry revealed that irradiation triggered the oligomerization of chlorpromazine molecules. The oligomerized chlorpromazine showed a mixed type inhibition with inhibition constants of low micromolar range, indicative of enhanced inhibition. Taken together, these results suggest that oligomerized chlorpromazine could act as an active substance that might contribute to the therapeutic effects of this drug. 相似文献
84.
Thomas B Mandir AS West N Liu Y Andrabi SA Stirling W Dawson VL Dawson TM Lee MK 《PloS one》2011,6(1):e16706
Genetic and biochemical abnormalities of α-synuclein are associated with the pathogenesis of Parkinson's disease. In the present study we investigated the in vivo interaction of mouse and human α-synuclein with the potent parkinsonian neurotoxin, MPTP. We find that while lack of mouse α-synuclein in mice is associated with reduced vulnerability to MPTP, increased levels of human α-synuclein expression is not associated with obvious changes in the vulnerability of dopaminergic neurons to MPTP. However, expressing human α-synuclein variants (human wild type or A53T) in the α-synuclein null mice completely restores the vulnerability of nigral dopaminergic neurons to MPTP. These results indicate that human α-synuclein can functionally replace mouse α-synuclein in regard to vulnerability of dopaminergic neurons to MPTP-toxicity. Significantly, α-synuclein null mice and wild type mice were equally sensitive to neurodegeneration induced by 2'NH(2)-MPTP, a MPTP analog that is selective for serotoninergic and noradrenergic neurons. These results suggest that effects of α-synuclein on MPTP like compounds are selective for nigral dopaminergic neurons. Immunoblot analysis of β-synuclein and Akt levels in the mice reveals selective increases in β-synuclein and phosphorylated Akt levels in ventral midbrain, but not in other brain regions, of α-synuclein null mice, implicating the α-synuclein-level dependent regulation of β-synuclein expression in modulation of MPTP-toxicity by α-synuclein. Together these findings provide new mechanistic insights on the role α-synuclein in modulating neurodegenerative phenotypes by regulation of Akt-mediated cell survival signaling in vivo. 相似文献
85.
Shabhat Rasool Rubiya Dar Mosin S Khan Sheikh Gazalla Ayoub Sabia Rashid Muneeb U Rehman Tariq Jan Meenu A Qureshi Khurshid I Andrabi 《International Journal of Biochemistry and Molecular Biology》2021,12(1):35
High Myopia (HM) is a common complex-trait eye disorder. There is essential evidence that genetic factors play a significant role in the development of nonsyndromic high myopia. Identification of susceptibility genes of high myopia will shed light on the pathophysiological mechanism underlying their genesis. This was a case control study examining the prospect of association of DLGAP1, EMILIN2 & MYOM1 genes on MYP2 locus in purely ethnic (Kashmiri) population representing a homogeneous cohort. Genomic DNA was extracted using phenol chloroform and salting out method. Extracted DNA was genotyped for polymorphic variations in MYOM1, EMILIN2 and DLGAP1 genes involving Sanger di-deoxy method. Allele frequencies were tested for Hardy-Weinberg disequilibrium in 224 cases and compared with 220 emmetropic controls. In DLGAP1, documented single nucleotide polymorphism (SNP); Pro517Pro was observed. A previously reported Asn451Asn SNP was observed in EMILIN2. MYOM1 showed five polymorphic variations; two in coding region (Gly333Gly & Gly341Ala) and three intronic (c.1022+23, G>A; c.3418+44 G>T & c.3418+65; C>G). All of the elucidated SNPs were having statistical significant role in increasing or decreasing the risk of disease. Although not statistically significant, a novel Glu507Lys SNP was observed in DLGAP1 (P>0.05). In silico predictions showed MYOM1 Gly341Ala to be benign & tolerated substitution while as DLGAP1 Glu507Lys to be possibly damaging substitution. The studied SNPs followed Over-Dominant, Recessive and Co-Dominant mode of inheritance with specific haplotypes associated with the disease. Our study reveals the involvement of MYP2 locus candidate gene polymorphism in the pathogenesis of HM. 相似文献
86.
Sadaf Rafiq Z.A. Rather Reyaz Ahmad Bhat I.T. Nazki Mohammad S. AL-Harbi Neelofar Banday Iqra Farooq Bassem N. Samra M.H. Khan Atef F. Ahmed Najmah Andrabi 《Saudi Journal of Biological Sciences》2021,28(12):7581
Micropropagation protocol of Oriental Hybrid Lilium cv. Ravenna was developed using bulb scale segments (Basal and Tip) as explants. Surface sterilization of healthy bulb scales with carbendazim 200 ppm for 30 min, then 0.1 percent mercuric chloride for 10 min, then 70% ethyl alcohol for 30 s was superior to all other treatments in recording highest culture asepsis (77.08%) and higher explant survival (86.12%). Explant survival was higher in basal segments (88.54%) compared to tip segments (85.52%). Highest culture establishment was recorded in basal scale segments (68.26%) followed by tip scale segments (55.21%). MS medium augmented with 0.50 mgl−1 Naphthalene acetic acid and 2.0 mgl−1. 6-Benzylamino Purine recorded maximum culture establishment (76.17%), highest bulblet number/explant (5.52) with maximum length of shoots (2.20 cm) and number of leaves (3.39). This treatment combination of growth regulators resulted in highest shoot proliferation (83.33%) along with maximum shoot number (2.41explant−1), shoot length (2.35 cm) and leaf number (5.44) of micro shoots during proliferation stage. Rooting of explants was superior with Indole-3-butyric acid compared to Naphthalene acetic acid. Highest rooting of 92.71% along with maximum number of primary roots shoot−1 (12.06), maximum primary root length (3.17 cm) was documented in Murashige and Skoog medium added with Indole-3-butyric acid 1.50 mgl−1 with best ex vitro survival rate (98.96%) of rooted plantlets during primary hardening in perlite + vermiculite (1:1) mixture. 相似文献
87.
88.
JOHANNA ROUTA SEPPO KELLOMÄKI ANTTI KILPELÄINEN HELI PELTOLA HARRI STRANDMAN 《Global Change Biology Bioenergy》2011,3(6):483-497
The aim of this work was to study the sensitivity of carbon dioxide (CO2) emissions from wood energy to different forest management regimes when aiming at an integrated production of timber and energy biomass. For this purpose, the production of timber and energy biomass in Norway spruce [Picea abies (L.) Karst] and Scots pine (Pinus sylvestris L.) stands was simulated using an ecosystem model (SIMA) on sites of varying fertility under different management regimes, including various thinning and fertilization treatments over a fixed simulation period of 80 years. The simulations included timber (sawlogs, pulp), energy biomass (small‐sized stem wood) and/or logging residues (top part of stem, branches and needles) from first thinning, and logging residues and stumps from final felling for energy production. In this context, a life cycle analysis/emission calculation tool was used to assess the CO2 emissions per unit of energy (kg CO2 MWh?1) which was produced based on the use of wood energy. The energy balance (GJ ha?1) of the supply chain was also calculated. The evaluation of CO2 emissions and energy balance of the supply chain considered the whole forest bioenergy production chain, representing all operations needed to grow and harvest biomass and transport it to a power plant for energy production. Fertilization and high precommercial stand density clearly increased stem wood production (i.e. sawlogs, pulp and small‐sized stem wood), but also the amount of logging residues, stump wood and roots for energy use. Similarly, the lowest CO2 emissions per unit of energy were obtained, regardless of tree species and site fertility, when applying extremely or very dense precommercial stand density, as well as fertilization three times during the rotation. For Norway spruce such management also provided a high energy balance (GJ ha?1). On the other hand, the highest energy balance for Scots pine was obtained concurrently with extremely dense precommercial stands without fertilization on the medium‐fertility site, while on the low‐fertility site fertilization three times during the rotation was needed to attain this balance. Thus, clear differences existed between species and sites. In general, the forest bioenergy supply chain seemed to be effective; i.e. the fossil fuel energy consumption varied between 2.2% and 2.8% of the energy produced based on the forest biomass. To conclude, the primary energy use and CO2 emissions related to the forest operations, including the production and application of fertilizer, were small in relation to the increased potential of energy biomass. 相似文献
89.
90.
ZSOLT PÉNZES GEORGE MELIKA ZOLTÁN BOZSÓKI PÉTER BIHARI ISTVÁN MIKÓ MAJID TAVAKOLI JULI PUJADE‐VILLAR BALÁZS FEHÉR DÁVID FÜLÖP KRISZTIÁN SZABÓ MIKLÓS BOZSÓ BOTOND SIPOS KÁLMÁN SOMOGYI GRAHAM N. STONE 《Systematic Entomology》2009,34(4):688-711
Several unanswered questions remain regarding the taxonomy and phylogeny of inquiline gallwasps (Cynipidae: Synergini), obligate inhabitants of plant galls induced primarily by other gallwasps (Cynipidae: Cynipini and Diplolepidini). Here we use morphological and molecular data to revise the inquiline genus Synophrus, members of which are notable for extensively modifying the structure of galls induced by oak gallwasp hosts on oaks in the section Cerris of Quercus subgenus Quercus in the Western Palaearctic. Previous taxonomic treatments have recognized three Western Palaearctic species of Synophrus: S. pilulae, S. politus and S. olivieri. Our results support the establishment of four additional Western Palaearctic species: Synophrus hungaricus sp.n. , S. libani sp.n. , S. syriacus sp.n. and S. hispanicus sp.n. We describe and diagnose these new taxa, analyse their phylogenetic relationships, and show that Synophrus inquilines are able to impose their own gall phenotypes on those of their hosts. We provide an updated key to Synophrus. 相似文献