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the influence of time and temperature on molecular gut content analysis： Adalia bipunctata fed with Rhopalosiphum padi

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Insect Science 2007年第5期14卷 353-358页

作者： STUART MCMILLAn anna-KARIn KUUSK anna CASSELLUnDHAGEn BARBARA EKBOM Department of Ecology Swedish University of Agricultural Sciences Box 7044 750 07 Uppsala Sweden

Gut content analysis is a useful tool when studying arthropod predator-prey interactions. We used polymerase chain reaction （PCR） technique to examine how detection of prey DnA in the gut content of predators was influenced by digestion time and temperature. Such knowledge is critical before applying PCR-based gut content analysis to field collected predators. Larvae of the two-spotted ladybeetle （Adalia bipunctata L.） were fed with the bird cherry-oat aphid （Rhopalosiphum padi L.） at either 21℃ or 14℃. After consuming one aphid, the predators were allowed to digest the prey for a range of time periods up to 24 hours. the influence of temperature on A. bipunctata feeding behavior was also recorded. From the fed larvae, total DnA was extracted and PCR reactions with R. padi specific primers were run. the number ofA. bipunctata that tested positive for R. padi DnA was negatively related to the length of digestion time. Temperature influenced larval feeding behavior but did not have a significant effect on R. padi DnA detection. After pooling the data from both temperature treatments we estimated the time point when R. padi DnA could be amplified from 50% of the fed A. bipunctata by PCR to be 4.87 hours. With such a rapid decrease in prey DnA detection success, positive PCR reactions will most likely be the result of predation events occurring shortly before capture. If a defined digestion temperature range has proven not to influence prey detection, PCR data obtained from predators collected within that particular range can be interpreted in the same way.

关键词： Adalia bipunctata aphidophagous predator prey DnA detection success gut content analysis PCR Rhopalosiphum padi

CYP24A1 inhibition facilitates the anti-tumor effect of vitamin D3 on colorectal cancer cells

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World Journal of Gastroenterology 2013年第17期19卷 2621-2628页

作者： János P Kósa Péter Horváth János Wlfling Dóra Kovács Bernadett Balla Péter Mátyus Evelin Horváth Gábor Speer István Takács Zsolt nagy Henrik Horváth Péter Lakatos 1 st Department of Internal Medicine Semmelweis University Department of Organic Chemistry University of Szeged Department of Organic Chemistry Semmelweis University

AIM:the effects of vitamin D3 have been investigated on various tumors, including colorectal cancer (CRC). 25-hydroxyvitamin-D3-24-hydroxylase (CYP24A1), the enzyme that inactivates the active vitamin D3 metabolite 1,25-dihydroxyvitamin D3 (1,25-D3), is considered to be the main enzyme determining the biological halflife of 1,25-D3. During colorectal carcinogenesis, the expression and concentration of CYP24A1 increases significantly, suggesting that this phenomenon could be responsible for the proposed efficacy of 1,25-D3 in the treatment of CRC. the aim of this study was to investigate the anti-tumor effects of vitamin D3 on the human CRC cell line Caco-2 after inhibition of the cytochrome P450 component of CYP24A1 activity. MEthODS:We examined the expression of CYP24A1 mRnA and the effects of 1,25-D3 on the cell line Caco-2 after inhibition of CYP24A1. Cell viability and proliferation were determined by means of sulforhodamine-B staining and bromodeoxyuridine incorporation, respectively, while cytotoxicity was estimated via the lactate dehydrogenase content of the cell culture supernatant. CYP24A1 expression was measured by realtime reverse transcription polymerase chain reaction. A number of tetralone compounds were synthesized to investigate their CP24A1 inhibitory activity. RESULTS:In response to 1,25-D3, CYP24A1 mRnA expression was enhanced significantly, in a time- and dose-dependent manner. Caco-2 cell viability and proliferation were not influenced by the administration of 1,25-D3 alone, but were markedly reduced by coadministration of 1,25-D3 and KD-35, a CYP24A1-inhibiting tetralone. Our data suggest that the mechanism of action of co-administered KD-35 and 1,25-D3 does not involve a direct cytotoxic effect, but rather the inhibition of cell proliferation. COnCLUSIOn:these findings demonstrate that the selective inhibition of CYP24A1 by compounds such as KD-35 may be a new approach for enhancement of the anti-tumor effect of 1,25-D3 on CRC.

关键词： Colorectal cancer CYP24A1 inhibition Vitamin D3 Tetralone derivatives Caco-2 cell culture

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孕震过程与地壳电磁辐射关系的模拟研究

世界地震译丛 1991年第2期22卷 20-26页

作者： gers.,nI 金耀

the effect of growth conditions on the relationship between fine root and foliage biomass

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Journal of Forestry Research 2022年第5期33卷 1585-1591页

作者： Yury Karpechko anna Karpechko Andrej Tuyunen Forest Research Institute of the Karelian Research Centre of the Russian Academy of Sciences 11 Pushkinskaya St.PetrozavodskKareliaRussia 185910

this article examines the physiological relationships between fine roots and foliage, and how their biomass ratio correlates with changes in stand quality class. the biomass of fine roots ≤ 3 mm in diameter of spruce stands in the Republic of Karelia (northwest Russia) was determined by the soil monolith method. Foliage biomass was calculated using a previously designed technique from the standing stock, average height and quality class of the stand. A relation between fine-root: foliage biomass ratio and stand quality class (representing soil fertility) has been established. the closest correlation between fine-root: foliage biomass ratio and stand quality based on soil fertility was for the 1-2 mm root fraction. Analysis of the water flux balance in the trees revealed a correlation between fine-root: foliage ratio and the ratio of the specific volume of transpiration by the stand to the specific volume of water uptake from the soil by roots. theoretical explanations for the decrease in fine-root: foliage biomass ratios with increasing stand quality class are offered.

关键词： Fine-root biomass Foliage biomass Stand quality class Soil fertility

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Radial and longitudinal density variations in Abies cephalonica and Pinus halepensis

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Journal of Forestry Research 2023年第3期34卷 853-863页

作者： Vasiliki Dimou anna Tsaliki Kyriaki Kitikidou Laboratory of Forest Technology Department of Forestry and Management of the Environment and Natural ResourcesDemocritus University of Thrace193 Pandazidou68200 OrestiadaPCGreece Laboratory of Forest Biometry-Biostatistics Department of Forestry and Management of the Environment and Natural ResourcesDemocritus University of Thrace193 Pandazidou68200 OrestiadaPCGreece

Basic wood density is an excellent indicator of quality,it is correlated with numerous physical,physiological and mechanical characteristics of a species and is a good descriptor of wood quality and important indicator of tree performance in community *** accurate method is thus needed to estimate wood *** standard way is to calculate the ratio of the oven-dried mass of a wood sample divided by its green volume,but wood characteristics within and between growth rings are highly variable;the density can vary in the longitudinal and the radial *** present study investigates the longitudinal and radial fl uctuations in the basic density of Abies cephalonica Loud and Pinus halepensis *** logs were cut from four diff erent trees for each species and 16 discs were formed(two discs from each log,one at the base and one at the top).Each disc was cut into cubes where their distance from the pith was measured and then sorted into 2 cm wide concentric *** results revealed a mild decreasing trend in basic density from the foot of the trunk upward for both *** pith in both species also seems to have a relatively high density,which in the immediate next growth rings decreases only to resume increasing toward the bark.

关键词： Aleppo pine Physical properties Specifi c gravity Wood quality

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Brillouin distributed time-domain sensing in optical fibers:state of the art and perspectives

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Frontiers of Optoelectronics 2010年第1期3卷 13-21页

作者： Luc théVEnAZ Ecole Polytechnique Fédérale de Lausanne Institute of Electrical Engineering

Optical fiber sensors based on stimulated Brillouin scattering have now clearly demonstrated their excellent capability for long-range distributed strain and temperature measurements. the fiber is used as sensing element, and a value for temperature and/or strain can be obtained from any point along the fiber. After explaining the principle and presenting the standard implementation,the latest developments in this class of sensors will be introduced, such as the possibility to measure with a spatial resolution of 10 cm and below while preserving the full accuracy on the determination of temperature and strain.

关键词： optical fiber optical fiber sensors distributed fiber sensors stimulated Brillouin scattering nonlinear fiber optics

Stomatal regulation: Role of H2S-induced persulfidation in ABA signaling

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Molecular Plant 2021年第6期14卷 858-860页

作者： anna Siodmak Heribert Hirt DARWIn21 Center for Desert AgricultureKing Abdullah University of Science and TechnologyThuwalSaudi Arabia Max F.Perutz Laboratories University of ViennaDr.Bohrgasse 91030 ViennaAustria

Hydrogen sulfide(H2S)is an important signaling molecule in *** is a small gasotransmitter with high permeativity through lipid membranes.H2S can convert the mercapto groups(Cys–SH)of the amino acid cysteine into hydropersulfide groups(–Cys–SSH).this process is called *** modifications such as persulfidation can play an important role in protein functionality,altering protein conformation and/or *** plants,H2S can be generated within guard cells by CYSTEInE-DESULFHYDRASES,such as DES1,by degradation of cysteines into H2S,ammonia,and pyruvate(Zhang et al.,2020).H2S was reported to take part in physiological processes,such as stress response,and in the regulation of the functions of phytohormones such as salicylic acid and abscisic acid(ABA)(Pandey and Gautam,2020).Although the mechanism of how H2S affects ABA signaling pathways is not well understood,two recent studies by Chen et al.(2020)and Zhou et al.(2021)shed light on this topic,reporting how H2S-induced persulfidation regulates the stomatal ABA signaling pathway.

关键词： sulfide ammonia convert

the Serum Level of CD16 + 56 in Zona

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Journal of Cosmetics, Dermatological Sciences and Applications 2021年第1期11卷 1-9页

作者： nguyễn Lan Anh Bùi thị Vân Vũ thu Trang Đặng Trung thành nguyễn thị Quỳnh Trang nguyễn thị Tuấn Đặng Văn Em Department of Dermatology Venereology Allergy 108 Military Central Hospital Ha Noi Vietnam Department of Immunology 108 Military Central Hospital Ha Noi Vietnam

Objectives: To study the change of CD16 + 56 in zona. Materials and Methods: 62 zona patients admitted at Inpatient Department of Dermatology, Venereology Allergy, 108 Military Central Hospital, and 30 healthy volunte... 详细信息

ng>Objectives:ng> To study the change of CD16 + 56 in zona. ng>Materials and Methods:ng> 62 zona patients admitted at Inpatient Department of Dermatology, Venereology Allergy, 108 Military Central Hospital, and 30 healthy volunteers who were matched for age and sex participated in this study. Prospective, cross-sectional study with controls was conducted. We measured the number of CD16 + CD56 by flow cytometry using FACS Callibur. ng>Results:ng> the mean level of CD16 + 56 in zona patients was 253 ± 200 (106 cells/l), which was lower than that of control group but then increased after treatment. the change of CD16 + 56 did not correlate with patients’ age. Patients who were in severe condition or had affected size from 3% or more had a lower number of CD16 + 56 than control group. ng>Conclusion:ng> the number of CD16 + 56 in zona patients were lower than that of healthy people.

关键词： CD16 + 56 Zona

Coordination of Plastid and Light Signaling Pathways upon Development of Arabidopsis Leaves under Various Photoperiods

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Molecular Plant 2012年第4期5卷 799-816页

作者： anna Lepisto Eevi Rintamaki Molecular Plant Biology Department of Biochemistry and Food Chemistry University of Turku FI-20014 Turku Finland

Plants synchronize their cellular and physiological functions according to the photoperiod （the length of the light period） in the cycle of 24 h. Photoperiod adjusts several traits in the plant life cycle, including flowering and senes- cence in annuals and seasonal growth cessation in perennials. Photoperiodic development is controlled by the coordinated action of photoreceptors and the circadian clock. During the past 10 years, remarkable progress has been made in under- standing the molecular mechanism of the circadian clock, especially with regard to the transition of Arabidopsis from the vegetative growth to the reproductive phase. Besides flowering photoperiod also modifies plant photosynthetic struc- tures and traits. Light signals controlling biogenesis of chloroplasts and development of leaf photosynthetic structures are perceived both by photoreceptors and in chloroplasts. In this review, we provide evidence suggesting that the photope- riodic development of Arabidopsis leaves mimics the acclimation of plant to various light intensities. Furthermore, the chloroplast-to-nucleus retrograde signals that adjust acclimation to light intensity are proposed to contribute also to the signaling pathways that control photoperiodic acclimation of leaves.

关键词： acclimation chloroplast biology circadian clock leaf/vegetative development light signaling photomor-phogenesis plastid signaling.