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81.
Ali JG Alborn HT Campos-Herrera R Kaplan F Duncan LW Rodriguez-Saona C Koppenhöfer AM Stelinski LL 《PloS one》2012,7(6):e38146
While the role of herbivore-induced volatiles in plant-herbivore-natural enemy interactions is well documented aboveground, new evidence suggests that belowground volatile emissions can protect plants by attracting entomopathogenic nematodes (EPNs). However, due to methodological limitations, no study has previously detected belowground herbivore-induced volatiles in the field or quantified their impact on attraction of diverse EPN species. Here we show how a belowground herbivore-induced volatile can enhance mortality of agriculturally significant root pests. First, in real time, we identified pregeijerene (1,5-dimethylcyclodeca-1,5,7-triene) from citrus roots 9-12 hours after initiation of larval Diaprepes abbreviatus feeding. This compound was also detected in the root zone of mature citrus trees in the field. Application of collected volatiles from weevil-damaged citrus roots attracted native EPNs and increased mortality of beetle larvae (D. abbreviatus) compared to controls in a citrus orchard. In addition, field applications of isolated pregeijerene caused similar results. Quantitative real-time PCR revealed that pregeijerene increased pest mortality by attracting four species of naturally occurring EPNs in the field. Finally, we tested the generality of this root-zone signal by application of pregeijerene in blueberry fields; mortality of larvae (Galleria mellonella and Anomala orientalis) again increased by attracting naturally occurring populations of an EPN. Thus, this specific belowground signal attracts natural enemies of widespread root pests in distinct agricultural systems and may have broad potential in biological control of root pests. 相似文献
82.
Ben Abdeljelil J Saghrouni F Cabaret O Boukadida J Bretagne S Ben Saïd M 《DNA and cell biology》2012,31(7):1161-1166
The nosocomial transmission of Candida albicans in neonatal intensive care units (NICUs) is an increasing concern and understanding the route of this transmission is critical for adequate infection control measures. The aim of our study was to assess the likeliness of nosocomial acquisition of C. albicans in the NICU of Farhat Hached hospital in Sousse (Tunisia). We genotyped 82 isolates from 40 neonates and 7 isolates from 5 health care workers (HCWs) with onychomycosis, by using CDC3 microsatellite length polymorphism (MLP) and the high-resolution melting (HRM) analysis. Combined MLP and HRM CD3 analysis led to the delineation of 12 genotypes. Five temporal clustering caused by five genotypes occurred during the study period. Three of these genotypes were isolated in both neonates and HCWs. The first clustering included 28 isolates obtained between January 2003 and May 2004 from 16 neonates and 2 HCWs. The second clustering included three isolates collected in 2004 from three neonates and two HCWs. The third clustering included 11 isolates obtained from 6 neonates and 1 HCW in 2006. The two remaining clustering could not be associated with any HCW's contamination. These results argue for the nosocomial transmission of C. albicans in our NICU. The combined MLP and HRM analysis is a rapid first approach for tracking cross-contamination. 相似文献
83.
Meligy FY Shigemura K Behnsawy HM Fujisawa M Kawabata M Shirakawa T 《In vitro cellular & developmental biology. Animal》2012,48(4):203-215
The objective of the study is to evaluate efficiency of in vitro isolation and myogenic differentiation of mesenchymal stem
cells (MSCs) derived from adipose connective tissue (AD-MSCs), bone marrow (BM-MSCs), and skeletal muscle tissue (MC-MSCs).
MSCs were isolated from adipose connective tissue, bone marrow, and skeletal muscle tissue of two adult 6-wk-old rats. Cultured
MSCs were treated with 5-azacytidine (AZA) to induce myogenic differentiation. Isolated MSCs and differentiated cells were
evaluated by immunocytochemistry (ICC), fluorescence-activated cell sorting (FACS), PCR, and RT-PCR. AD-MSCs showed the highest
proliferation rate while BM-MSCs had the lowest one. In ICC, isolated MSCs had strong CD90- and CD44-positive expression and
negative expression of CD45, CD31, and CD34, while AZA-treated MSCs had strong positive desmin expression. In FACS analysis,
AD-MSCs had the highest percentage of CD90- and CD44-positive-expressing cells (99% and 96%) followed by BM-MSCs (97% and
94%) and MC-MSCs (92% and 91%).At 1 wk after incubation with AZA treatment, the peak of myogenin expression reached 93% in
differentiated MC-MSCs, 83.3% in BM-MSCs, and 77% in AD-MSCs. MSCs isolated from adipose connective tissue, bone marrow, and
skeletal muscle tissue have the same morphology and phenotype, but AD-MSCs were the most easily accessible and had the highest
rate of growth on cultivation and the highest percentage of stem cell marker expression. Moreover, although MC-MSCs showed
the highest rate of myogenic differentiation potential and expression of myoblast markers, AD-MSCs and BM-MSCs still can be
valuable alternatives. The differentiated myoblastic cells could be an available new choice for myoblastic auto-transplantation
in regeneration medicine. 相似文献
84.
Imamoğlu N Uyanik F Kocaoğlu Güçlü B Erdem O Cem Liman B Dönmez Altuntaş H 《Biological trace element research》2008,125(2):133-140
We report the effects of chromium picolinate (CrPic) on micronucleus frequency, morphology of lymphocytes, and lipid peroxidation
in calves. Twenty-four Holstein calves were selected for the study. They were kept in a farm and were fed a commercially available
calf diet and alfalfa, ad libitum. The animals were divided into three groups of eight subjects each and were treated as follows:
The first group was supplemented with a daily dose of 200 μg Cr as chromium picolinate; a second group received 400 μg Cr
per day and a third group that served as control received no supplemental chromium. After 12-week supplementation, blood samples
were collected to determine the micronucleus frequency, the apoptotic cell percentage, and the malondialdehyde (MDA) and blood
chromium levels. In both supplemented groups, the cells had irregularly shaped and segmented nuclei. Supplementation also
increased the percentage of apoptotic cells (p < 0.001) and serum MDA (p < 0.01) and slightly increased the chromium levels. The animals supplemented with 400 μg showed a significant increase of
micronucleus frequency (p < 0.01). The results of this study suggest that supplementation with 200 and 400 μg chromium as chromium picolinate may lead
to cytotoxicity. The higher level of supplementation may also have genotoxic effects. However, further studies investigating
the mechanism of the action of CrPic are required. 相似文献
85.
Maturity assessment of composted olive mill wastes using UV spectra and humification parameters 总被引:4,自引:1,他引:3
In this study, two olive mill wastes - exhausted olive cake (EOC) and paste of olive mill wastewater naturally dehydrated (POMW) - were co-composted and mixed with 25% sesame bark (SB). The humification process was evidenced by quantifying the humic substances and the generally accepted humification indices: (i) the ratio of humic acid (HA) carbon to fulvic acid (FA) carbon (CHA/CFA), (ii) the ratio of water soluble organic carbon (CW) to total organic nitrogen (Cw/Norg), (iii) and the ratio of humic acid carbon to total organic carbon CHA/Corg and by determining the absorbance ratios: E2/E4, E2/E6 and E4/E6. The results showed that the time required to reach maturity was dependant on the chemical properties of the initial raw materials used. The compost including EOC had more nitrogen and synthesised more polymerised HA, the POMW compost also had acceptable degrees of stability and maturity at the end of the process. Maturation was confirmed by a decline in Cw below 1.7, an increase in nitrogen, in HA, in CHA/CFA and an elimination of phytotoxicity. Composts produced with olive mill wastes, experimented on potato culture in the field, can be considered beneficial to soils because of their humification indexes and no toxicity. 相似文献
86.
The embryonic poly(A)-binding protein (EPAB) functions in the translational regulation of the maternal messenger RNAs (mRNAs) required during oocyte maturation, fertilization, and early embryo development. Since there is no antibody specific to mammalian EPAB protein, all studies related to the Epab gene could be performed at the mRNA levels except for the investigations in the Xenopus. In this study, we have produced an EPAB-specific antibody. When we examined its expressional distribution in the mouse gonadal and somatic tissues, the EPAB protein was found to be expressed only in the mouse ovary and testis tissues, but it is undetectable level in the somatic tissues including stomach, liver, heart, small intestine, and kidney. Additionally, the spatial and temporal expression patterns of the EPAB and poly(A)-binding protein cytoplasmic 1 (PABPC1) proteins were analyzed in the mouse germinal vesicle (GV) and metaphase II (MII) oocytes, one-cell, and two-cell embryos. While EPAB expression gradually decreased from GV oocytes to two-cell embryos, the PABPC1 protein level progressively increased from GV oocytes to one-cell embryos and remarkably declined in the two-cell embryos ( P < 0.05). We have also described herein that the EPAB protein interacted with Epab, Pabpc1, Ccnb1, Gdf9, and Bmp15 mRNAs dependent upon the developmental stages of the mouse oocytes and early embryos. As a result, we have first produced an EPAB-specific antibody and characterized its expression patterns and interacting mRNAs in the mouse oocytes and early embryos. The findings suggest that EPAB in cooperation with PABPC1 implicate in the translational control of maternal mRNAs during oogenesis and early embryo development. 相似文献
87.
K. S. Ramaswamy Claudio D. Carrasco Tasneem Fatma † James W. Golden 《Molecular microbiology》1997,23(6):1241-1249
The fdxN element, along with two other DNA elements, is excised from the chromosome during heterocyst differentiation in Anabaena sp. strain PCC 7120. Previous work showed that rearrangement of the fdxN element requires the xisF gene, which encodes a site-specific recombinase, and suggested that at least one other heterocyst-specific factor is involved. Here we report that the xisH and xisl genes are necessary for the heterocyst-specific excision of the fdxN element. Deletion of a 3.2 kb region downstream of the xisF gene blocked the fdxN-element rearrangement in hetero-cysts. The 3.2 kb deletion was complemented by the two overlapping genes xisH and xisl. Interestingly, extra copies of xlsHI on a replicating plasmid resulted in the xisF-dependent excision of the fdxN element in vegetative cells. Therefore, xisHI are involved in the control of cell-type specificity of the fdxN rearrangement. The xisHI genes had no effect on the two other DNA rearrangements. The xisHl-induced excision of the fdxN element produced strains lacking the element and demonstrates that the 55 kb element contains no essential genes. xisH and xisl do not show similarity to any known genes. 相似文献
88.
Silan F Gultekin Y Atik S Kilinc D Alan C Yildiz F Uludag A Ozdemir O 《Molecular biology reports》2012,39(2):1595-1599
Prostate cancer is a common malignancy that develops by structural mutation(s) and/or other genetic alterations in specific
genes.The G to T transversions in codon 12 and C to T transitions in codon 13 of KRAS proto-oncogene are predominant point
mutations that occur in about 20% of different cancers in human. In the current study it was aimed to investigate the prevalence
and predictive significance of KRAS mutations in patients with prostate carcinomas. In a total of 30 fresh tumoural tissue
specimens were investigated in patients with prostate carcinoma. All tumoural specimens were histo-pathologically diagnosed
and genotyped for codon 12, 13 KRAS point mutations by reverse hybridisation and direct sequencing methods. KRAS mutations
were found in 12 (40%) samples with 29 samples deriving from adenocarcinomas and 1 sample was small cell prostate carcinoma.
In 1 (3.44%) sample codon 12 was found to be mutated and in 2 (6.8%) samples codon 13 and in 9 (31%) samples combined codon
12 and 13 were found to be mutated particularly in higher grade of tumoural tissues. Our study, based on representative collection
of human prostate tumours, indicates that combined mutations in codons 12 and 13 KRAS are relatively infrequent and most commonly
occur in prostate carcinomas. 相似文献
89.
Evolution and ecology are essential to an understanding of biology, but questions remain as to when and how young children can learn about these concepts. The concept of adaptation represents an opportunity for children to engage with these ideas, and this article presents several lessons used to teach adaptation to children aged three through six at a summer Science Technology Engineering Art and Mathematics camp. The lessons incorporate interactive yarn stories to illustrate particular adaptations in three biomes: desert, arctic tundra, and deciduous forest. The yarn stories also introduce environmental features and particular organisms that are used in subsequent investigations. Examples and assessment data from preschool children in this camp are used to illustrate young children’s emerging understandings of adaptation throughout these lessons. 相似文献
90.
A strain of long-chain alkane–degrading bacteria, BT1A, was isolated from oil-contaminated soil in Diyarbak?r, in the southeast of Turkey. Morphological, biochemical, and physiological characterization and 16S rRNA gene sequence analysis showed that the strain BT1A was a member of Acinetobacter genus, and it was found to be closely related to Acinetobacter baumannii. The strain BT1A was able to utilize crude petroleum as carbon and energy sources in order to grow. Among the aliphatic hydrocarbons, growth was observed only in the medium containing long-chain alkanes (tridecane, pentadecane, and hexadecane) and squalene. Hexadecane was the most preferred hydrocarbon among the long-chain alkanes. Gas chromatography–mass spectrometry (GC-MS) analysis showed that BT1A degraded 83% of n-alkanes of 1% crude oil in 7 days. The present study indicates that the isolated strain can well be used for biodegradation of hydrocarbons in oil-contaminated sites. 相似文献