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Quantitative Differences (quantitative + difference)
Selected AbstractsDiamondback moth females oviposit more on plants infested by non-parasitised than by parasitised conspecificsECOLOGICAL ENTOMOLOGY, Issue 5 2008YASUYUKI CHOH Abstract 1.,When offered a choice, female diamondback moths (Plutella xylostella) oviposited more eggs on plants with non-parasitised conspecific larvae than on plants with parasitised larvae. 2.,The leaf area consumed by parasitised larvae was significantly lower than that by non-parasitised larvae. However, this quantitative difference in larval damage did not explain the female's ability to discriminate between plants with parasitised and non-parasitised larvae, as females showed an equal oviposition preference for plants infested by higher or lower densities of non-parasitised larvae. 3.,Pupal weight and duration of the larval stage of P. xylostella were independent of whether larvae were reared on plants that were previously infested by either non-parasitised or parasitised larvae. 4.,The larval parasitoid Cotesia vestalis did not distinguish between plants infested by non-parasitised larvae and plants infested by larvae that had already been parasitised by conspecific wasps. 5.,Based on these data, it can be concluded that the moth oviposition preference for plants infested by non-parasitised conspecifics relative to plants infested by parasitised conspecifics was not explained by plant quality or by the attractiveness of plants towards wasps. It is hypothesised that one of the reasons for this preference is avoidance of plants where a relatively high risk of parasitism is expected due to the emergence of parasitoids from the parasitised host larvae. [source] Purification and characterization of two bacteriocins produced by lactic acid bacteria isolated from Mongolian airagJOURNAL OF APPLIED MICROBIOLOGY, Issue 4 2006B. Batdorj Abstract Aims:, The aim of this study was to isolate and identify bacteriocin-producing lactic acid bacteria (LAB) issued from Mongolian airag (traditional fermented mare's milk), and to purify and characterize bacteriocins produced by these LAB. Methods and Results:, Identification of the bacteria (Enterococcus durans) was carried out on the basis of its morphological, biochemical characteristics and carbohydrate fermentation profile and by API50CH kit and 16S rDNA analyses. The pH-neutral cell-free supernatant of this bacterium inhibited the growth of several Lactobacillus spp. and food-borne pathogens including Escherichia coli, Staphylococcus aureus and Listeria innocua. The antimicrobial agent (enterocin A5-11) was heat stable and was not sensitive to acid and alkaline conditions (pH 2,10), but was sensitive to several proteolytic enzymes. Its inhibitory activity was completely eliminated after treatment with proteinase K and , -chymotrypsin. The activity was however not completely inactivated by other proteases including trypsin and pepsin. Three-step purification procedure with high recovery yields was developed to separate two bacteriocins. The applied procedure allowed the recovery of 16% and 64% of enterocins A5-11A and A5-11B, respectively, present in the culture supernatant with purity higher than 99%. SDS-PAGE analyses revealed that enterocin A5-11 has a molecular mass of 5000 Da and mass spectrometry analyses demonstrates molecular masses of 5206 and 5218 Da for fractions A and B, respectively. Amino acid analyses of both enterocins indicated significant quantitative difference in their contents in threonine, alanine, isoleucine and leucine. Their N -termini were blocked hampering straightforward Edman degradation. Conclusions:, Bacteriocins A5-11A and B from Ent. durans belong to the class II of bacteriocins. Significance and Impact of the Study:, Judging from molecular masses, amino acid composition and spectrum of activities, bacteriocins A5-11A and B from Ent. durans show high degree of similarity with enterocins L50A and L50B isolated from Enterococcus faecium (Cintas et al. 1998, 2000) and with enterocin I produced by Ent. faecium 6T1a, a strain originally isolated from a Spanish-style green olive fermentation (Floriano et al. 1998). [source] Simultaneous quantification of cell motility and protein-membrane-association using active contoursCYTOSKELETON, Issue 4 2002Dirk Dormann Abstract We present a new method for the quantification of dynamic changes in fluorescence intensities at the cell membrane of moving cells. It is based on an active contour method for cell-edge detection, which allows tracking of changes in cell shape and position. Fluorescence intensities at specific cortical subregions can be followed in space and time and correlated with cell motility. The translocation of two GFP tagged proteins (CRAC and GRP1) from the cytosol to the membrane in response to stimulation with the chemoattractant cAMP during chemotaxis of Dictyostelium cells and studies of the spatio-temporal dynamics of this process exemplify the method: We show that the translocation can be correlated with motility parameters and that quantitative differences in the rate of association and dissociation from the membrane can be observed for the two PH domain containing proteins. The analysis of periodic CRAC translocation to the leading edge of a cell responding to natural cAMP waves in a mound demonstrates the power of this approach. It is not only capable of tracking the outline of cells within aggregates in front of a noisy background, but furthermore allows the construction of spatio-temporal polar plots, capturing the dynamics of the protein distribution at the cell membrane within the cells' moving co-ordinate system. Compilation of data by means of normalised polar plots is suggested as a future tool, which promises the so-far impossible practicability of extensive statistical studies and automated comparison of complex spatio-temporal protein distribution patterns. Cell Motil. Cytoskeleton 52:221,230, 2002. © 2002 Wiley-Liss, Inc. [source] Screening for synaptic defects revealed a locus involved in presynaptic and postsynaptic functions in Drosophila embryosDEVELOPMENTAL NEUROBIOLOGY, Issue 2 2001Etsuko Takasu-Ishikawa Abstract To identify genes involved in synaptic functions, we screened lethal enhancer trap lines by monitoring synaptic activities at the neuromuscular junction in Drosophila embryos. It was found that MY7919, thus isolated, has moderate defects in both pre- and postsynaptic functions. The mean amplitudes of spontaneous as well as evoked synaptic currents were smaller than those in wild-type. The failure rate was higher than normal at any given concentration of external Ca2+, indicating that presynaptic functions were impaired. In addition, the mean amplitude of miniature synaptic currents was smaller, and the unitary current amplitudes of junctional glutamate receptor channels were slightly but significantly smaller. Thus, postsynaptic functions were also altered. The gene was cloned and found to be identical to the previously reported apontic (=tracheae defective) locus, which is believed to be a transcription factor expressed in the central nervous system (CNS) as well as in the head, tracheae, and heart. Immunohistochemical analysis using an antiapontic antibody revealed that the protein is localized to nuclei. Null alleles of the apontic locus were obtained by imprecise excision of the enhancer trap vector. Synaptic activities in null mutants were not different from those of the original allele, even though null homozygotes had uncontracted ventral nerve cords and more severe behavioral phenotypes. The morphology of the neuromuscular junction of the null mutant was qualitatively similar to that of wild-type, with the presence of typical pre- and postsynaptic specializations, but with some suggestions of quantitative differences. This strategy for screening mutants with synaptic defects will reveal more genes directly or indirectly affecting synaptic transmission. © 2001 John Wiley & Sons, Inc. J Neurobiol 48: 101,119, 2001 [source] Whole body extract of Mediterranean fruit fly males elicits high attraction in virgin femalesENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2008Vassilis G. Mavraganis Abstract The search for effective female attractants emanating from the host or body of fruit flies has been an area of intensive research for over three decades. In the present study, bodies of male Mediterranean fruit flies, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), were extracted with diethyl ether or methanol and subjected to gas chromatography,mass spectrometry. Analysis revealed substantial qualitative and quantitative differences between males from a laboratory culture and wild males captured alive in an orchard. Most notably, the hydrocarbon sesquiterpene (±)-,-copaene, which is known to be involved in the sexual behaviour of the species, was found in substantial amounts in wild males, but was not detected in laboratory males. In laboratory tests, 15 laboratory or wild male equivalents of diethyl ether extracts or combined diethyl ether and methanol extracts, or, to a lesser extent, methanol extracts alone, were found to attract virgin females. In a citrus orchard, traps baited with combined diethyl ether and methanol extracts of wild males attracted significantly more virgin females than traps baited with various doses of pyranone or blends of other compounds identified in the extracts or reported in the literature, such as ethyl acetate, ethyl-(E)-3-octenoate, and 1-pyrroline. Traps baited with blends of compounds, however, displayed substantial attractiveness compared to control (non-baited) traps. These results are important for better understanding the mating system of C. capitata as well as for further improving existing monitoring and control systems. [source] Cold adaptation in the marine bacterium, Sphingopyxis alaskensis, assessed using quantitative proteomicsENVIRONMENTAL MICROBIOLOGY, Issue 10 2010Lily Ting Summary The cold marine environment constitutes a large proportion of the Earth's biosphere. Sphingopyxis alaskensis was isolated as a numerically abundant bacterium from several cold marine locations, and has been extensively studied as a model marine bacterium. Recently, a metabolic labelling platform was developed to comprehensively identify and quantify proteins from S. alaskensis. The approach incorporated data normalization and statistical validation for the purpose of generating highly confident quantitative proteomics data. Using this approach, we determined quantitative differences between cells grown at 10°C (low temperature) and 30°C (high temperature). Cold adaptation was linked to specific aspects of gene expression: a dedicated protein-folding system using GroESL, DnaK, DnaJ, GrpE, SecB, ClpB and PPIase; polyhydroxyalkanoate-associated storage materials; a link between enzymes in fatty acid metabolism and energy generation; de novo synthesis of polyunsaturated fatty acids in the membrane and cell wall; inorganic phosphate ion transport by a phosphate import PstB homologue; TonB-dependent receptor and bacterioferritin in iron homeostasis; histidine, tryptophan and proline amino acid metabolism; and a large number of proteins without annotated functions. This study provides a new level of understanding on how important marine bacteria can adapt to compete effectively in cold marine environments. This study is also a benchmark for comparative proteomic analyses with other important marine bacteria and other cold-adapted organisms. [source] Efficient use of DNA molecular markers to construct industrial yeast strainsFEMS YEAST RESEARCH, Issue 8 2007Philippe Marullo Abstract Saccharomyces cerevisiae yeast strains exhibit a huge genotypic and phenotypic diversity. Breeding strategies taking advantage of these characteristics would contribute greatly to improving industrial yeasts. Here we mapped and introgressed chromosomal regions controlling industrial yeast properties, such as hydrogen sulphide production, phenolic off-flavor and a kinetic trait (lag phase duration). Two parent strains derived from industrial isolates used in winemaking and which exhibited significant quantitative differences in these traits were crossed and their progeny (50,170 clones) was analyzed for the segregation of these traits. Forty-eight segregants were genotyped at 2212 marker positions using DNA microarrays and one significant locus was mapped for each trait. To exploit these loci, an introgression approach was supervised by molecular markers monitoring using PCR/RFLP. Five successive backcrosses between an elite strain and appropriate segregants were sufficient to improve three trait values. Microarray-based genotyping confirmed that over 95% of the elite strain genome was recovered by this methodology. Moreover, karyotype patterns, mtDNA and tetrad analysis showed some genomic rearrangements during the introgression procedure. [source] Volatile constituents of different organs of Psoralea bituminosa L.FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2004Alessandra Bertoli Abstract The essential oil and SPME samples of the leaves, ,owers and seeds of Psoralea bituminosa L. were analysed by GC and GC,MS. We have investigated also the presence of monoterpene or aliphatic alcohol glucosides. The essential oils showed both qualitative and quantitative differences. The main constituents of the leaf and the ,ower essential oils were caryophyllene (23% and 18%, respectively), , -farnesene (15% and 6%, respectively), and germacrene D (24% and 18%, respectively). Signi,cant amounts (7%) of the same compounds were also directed in the seed essential oil, but tricyclene (11%) and , -pinene (50%) were the most important constituents of this oil. The volatile fractions of remaining leaf aqueous extracts after treatment with , -glucosidase revealed qualitative differences in comparison with the composition of the corresponding essential oils, and high levels of 3-hexen-1-ol (37%) and 1-octen-3-ol (27%) were observed. The SPME analysis of the fresh leaves, ,owers and seeds of P. bituminosa con,rmed the qualitative composition of the volatile oils, even if we detected signi,cative differences in the percentage ratio between monoterpenes and sesquiterpenes in comparison with the oils, where sesquiterpenes were the main components. In fact the variation of the monoterpenes, tricyclene, , -pinene and camphene between the leaf oil and the corresponding headspace sample was remarkable: tricyclene increased from 0.1% to 8%, , -pinene from 0.1% to 16% and camphene from 0.3% to 10% in the SPME samples. Copyright © 2004 John Wiley & Sons, Ltd. [source] The essential oils of Boesenbergia stenophylla R. M. Sm. as natural sources of methyl (E)-cinnamateFLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2003Fasihuddin bin Ahmad Abstract The rhizome and leaf oils of Boesenbergia stenophylla R. M. Sm. were analysed by gas chromatography on two columns of different polarity, retention indices and GC,MS. The oils were found to possess compositional similarities but quantitative differences in the concentration of each component. The oils are natural sources of methyl (E)-cinnamate, constituting 49.9,53.4% of the oils. They are also rich in sesquiterpenoids (39.8 and 40.3%, respectively) with , -elemene, , -elemene, , -santalene, , -humulene, , -muurolene, spathulenol, caryophyllene alcohol and kaur-16-ene as the main representatives. Copyright © 2003 John Wiley & Sons, Ltd. [source] Essential oils from flowers of Centaurea kotschyi var. kotschyi and C. kotschyi var. decumbens from TurkeyFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2003Kuddisi Ertugrul Abstract The compositions of the essential oils obtained from fresh capitula of Centaurea kotschyi var. kotschyi and Centaurea kotschyi var. decumbens, two endemic plants from Turkey, have been studied. Sesquiterpenes were the main components of both essential oils, with germacrene D (44.2%), , -caryophyllene (12.1%) and bicyclogermacrene (5.5%) in C. kotschyi var. kotschyi and germacrene D (29.4%), , -caryophyllene (11.2%), , -cedrene (7.1%) in C. kotschyi var. decumbens as the principal components. The qualitative and quantitative differences between the two essential oils are in agreement with the morphological observation that led to the differentiation of the two varieties.Copyright © 2003 John Wiley & Sons, Ltd. [source] Strength of signal: a fundamental mechanism for cell fate specificationIMMUNOLOGICAL REVIEWS, Issue 1 2006Sandra M. Hayes Summary:, How equipotent cells develop into complex tissues containing many diverse cell types is still a mystery. However, evidence is accumulating from different tissue systems in multiple organisms that many of the specific receptor families known to regulate cell fate decisions target conserved signaling pathways. A mechanism for preserving specificity in the cellular response that has emerged from these studies is one in which quantitative differences in receptor signaling regulate the cell fate decision. A signal strength model has recently gained support as a means to explain ,,/,, lineage commitment. In this review, we compare the ,,/,, fate decision with other cell fate decisions that occur outside of the lymphoid system to attain a better picture of the quantitative signaling mechanism for cell fate specification. [source] Assessment of genomic instability in breast cancer and uveal melanoma by random amplified polymorphic DNA analysisINTERNATIONAL JOURNAL OF CANCER, Issue 2 2002Sarantos Papadopoulos Abstract Some types of cancer have been associated with abnormal DNA fingerprinting. We used random amplified polymorphic DNA (RAPD) to generate fingerprints that detect genomic alterations in human breast cancer. Primers were designed by choosing sequences involved in the development of DNA mutations. Seventeen primers in 44 different combinations were used to screen a total of 6 breast cancer DNA/normal DNA pairs and 6 uveal melanoma DNA/normal DNA pairs. Forty-five percent of these combinations reliably detected quantitative differences in the breast cancer pairs, while only 18% of these combinations detected differences in the uveal melanoma pairs. Fourteen (32%) and 12 (27%) primers generated a smear or did not produce any band patterns in the first and second cases, respectively. Taking into account the ability of RAPD to screen the whole genome, our results suggest that the genomic damage in breast cancer is significantly higher than in uveal melanoma. Our study confirms other reports that the molecular karyotypes produced with random priming, called amplotypes, are very useful for assessing genomic damage in cancer. © 2002 Wiley-Liss, Inc. [source] Volatile compounds characterising Tunisian virgin olive oils: the influence of cultivarINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 5 2010Dhouha Krichene Summary In this work, the volatile profiles of four Tunisian virgin olive oils were established by headspace-solid phase microextraction and gas chromatography, using flame ionisation and mass spectrometer detectors. More than eighty compounds were isolated and characterised, representing 97,99% of the total GC area. The main volatile compounds present in the oil samples were determined quantitatively, the major constituents were often aldehydes, particularly (E)-2-hexenal (48,90%). Significant differences in the content of volatile constituents were observed. These quantitative differences were used to distinguish between virgin olive oils from different varieties. [source] Variation in mammalian proximal femoral development: comparative analysis of two distinct ossification patternsJOURNAL OF ANATOMY, Issue 3 2007Maria A. Serrat Abstract The developmental anatomy of the proximal femur is complex. In some mammals, including humans, the femoral head and greater trochanter emerge as separate ossification centres within a common chondroepiphysis and remain separate throughout ontogeny. In other species, these secondary centres coalesce within the chondroepiphysis to form a single osseous epiphysis much like the proximal humerus. These differences in femoral ontogeny have not been previously addressed, yet are critical to an understanding of femoral mineralization and architecture across a wide range of mammals and may have key implications for understanding and treating hip abnormalities in humans. We evaluated femora from 70 mammalian species and categorized each according to the presence of a ,separate' or ,coalesced' proximal epiphysis based on visual assessment. We found that ossification type varies widely among mammals: taxa in the ,coalesced' group include marsupials, artiodactyls, perissodactyls, bats, carnivores and several primates, while the ,separate' group includes hominoids, many rodents, tree shrews and several marine species. There was no clear relationship to body size, phylogeny or locomotion, but qualitative and quantitative differences between the groups suggest that ossification type may be primarily an artefact of femoral shape and neck length. As some osseous abnormalities of the human hip appear to mimic the normal morphology of species with coalesced epiphyses, these results may provide insight into the aetiology and treatment of human hip disorders such as femoroacetabular impingement and early-onset osteoarthritis. [source] Fungal flora associated with Tomicus piniperda L. in an area close to a timber yard in southern PolandJOURNAL OF APPLIED ENTOMOLOGY, Issue 8 2007R. Jankowiak Abstract:, The association between Tomicus piniperda L. (Col., Scolytinae) and fungi was studied in a Pinus sylvestris L. forest in Mielec-Mo,ciska. Fungi were isolated from overwintered adult beetles taken from two stands situated in different distance from timber yard. Two media were used for isolation. The results showed great diversity of fungi associated with T. piniperda: 1895 cultures, representing 64 species, were isolated. Penicillia and Hormonema dematioides were the dominant species, found in 20.2% and 17.8% of all beetles, respectively. A frequently isolated ophiostomatoid fungi was Ophiostoma minus. Qualitative and quantitative differences in the mycobiota composition of this insect between two stands were detected. The highest richness and diversity of fungal species appeared in the samples taken from the location where the trees were heavily damaged by shoot-feeding of T. piniperda. Differences were most clear for the pathogenic O. minus, which was a common fungal associate of the insects in this stand. [source] Acute oral toxicity of colchicine in rats: effects of gender, vehicle matrix and pre-exposure to lipopolysaccharideJOURNAL OF APPLIED TOXICOLOGY, Issue 5 2007Paddy L. Wiesenfeld Abstract The oral toxicity of a single administration by gavage (10, 20 or 30 mg kg,1 body weight) of colchicine (COL) was determined in young, mature male and female Sprague-Dawley rats. The effect of COL was evaluated in the presence or absence of additional treatment variables that included vehicle and lipopolysaccharide (LPS) pre-exposure. The vehicle for COL was either Half and Half cream (H & H) or saline, and each group included pretreatment with either saline or a low, minimally toxic dose (83 µg kg,1 body weight) of LPS. Colchicine toxicity in both male and female age-matched rats was characterized by progressively more severe dose-related clinical signs of toxicity. These included mortality, decreased body weight and feed intake during the first several days after dosing, with recovery thereafter in surviving animals. There were differences in the severity of the toxic response to COL between male and female rats. The most notable sex-related difference was in COL lethality. Female rats were two times more susceptible to the lethal effects of COL than male rats. Saline or H & H delivery vehicles did not result in any apparent qualitative or quantitative differences in COL toxicity. LPS pretreatment significantly potentiated COL lethality in both males and females, although the potentiation in males was greater than in females. LPS pretreatment modestly increased the COL induced anorexic effect in surviving males, but not in surviving female animals. LPS did not appear to modulate either the body weights or clinical signs of COL induced toxicity in surviving males or females. Copyright © 2007 John Wiley & Sons, Ltd. [source] A simple system for biofilm potential monitoring in drinking waterJOURNAL OF BASIC MICROBIOLOGY, Issue 1 2006Eric Delahaye Dr. SAGEP-EAU DE PARIS produces drinking water for the city of Paris (France). In order to supply a high quality water, one of the main SAGEP's concerns is to monitor the Biofilm Formation Potentials of the produced drinking waters. Biofilm incubators were installed at the outlet of three Water Treatment Plants (WTP). These incubators allowed biofilm formation and quantification in terms of Fixed Total Organic Carbon (FTOC), fixed culturable bacteria (HPC-R2A) and fixed total bacteria. During this study, quantitative differences appeared between the biofilms formed at the outlet of the three WTPs, leading to different classifications of the Biofilm Formation Potentials of the three produced waters, depending on the used parameter for biofilms quantification. This observation underlined the necessity of a multi-parametric approach for the study of biofilms. More generally, our results validated the use of these sturdy stainless steel incubators, highly adapted to industrial field conditions, for the monitoring of Biofilm Formation Potentials in drinking water networks. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Morph-specific selection on floral traits in a polymorphic plantJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 6 2010D. VANHOENACKER Abstract Correlations between phenotypic traits are common in many organisms, but the relative importance of nonadaptive mechanisms and selection for the evolution and maintenance of such correlations are poorly understood. In polymorphic species, morphs may evolve quantitative differences in additional characters as a result of morph-specific selection. The perennial rosette herb Primula farinosa is polymorphic for scape length. The short-scaped morph is less damaged by grazers and seed predators but is more strongly pollen limited than the long-scaped morph. We examined whether morph-specific differences in biotic interactions are associated with differences in selection on two other traits affecting floral display (number of flowers and petal size) and on one trait likely to affect pollination efficiency (corolla tube width) in three P. farinosa populations. Differences in selection between morphs were detected in one population. In this population, selection for more flowers and larger petals was stronger in the short-scaped than in the long-scaped morph, and although there was selection for narrower corolla tubes in the short-scaped morph, no statistically significant selection on corolla tube width could be detected in the long-scaped morph. In the study populations, the short-scaped morph produced more and larger flowers and wider corolla tubes. Current morph-specific selection was thus only partly consistent with trait differences between morphs. The results provide evidence of morph-specific selection on traits associated with floral display and pollination efficiency, respectively. [source] Two-Dimensional Electrophoretic Analysis of Soluble Leaf Proteins of a Salt-sensitive (Triticum aestivum) and a Salt-tolerant (T. durum) Cultivar in Response to NaCl StressJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 7 2007Mustafa YILDIZ Abstract In this research, 3-day-old etiolated wheat seedlings of Triticum aestivum L. cv. Ceyhan-99 (salt-sensitive) and T. durum Desf. cv. F,rat-93 (salt-tolerant) were grown in control and salt (150 mmol/L NaCl) treatments at a 15/25 °C temperature regime in the light for 12 days. Soluble proteins extracted from the first leaf tissues of two cultivars were analyzed by two-dimensional (2-D) electrophoresis in order to detect NaCl-induced changes. The soluble leaf protein profiles of cultivars were observed to be similar. However, quantitative differences in 74 proteins were detected in the salt treatment group, compared to the control. Among the 74 protein spots, 14 were common for two cultivars. As a result of NaCl treatment, two low-molecular-weight (LMW) proteins (28.9 and 30.0 kDa) and one intermediate-molecular-weight (IMW) protein (44.3 kDa) in cv. Ceyhan-99 and six LMW proteins (18.6, 19.4, 25.7, 25.9, 26 and 27.6 kDa) in cv. F,rat-93 were newly synthesized. The newly synthesized proteins were specific to each cultivar. In the F,rat-93 cultivar, four proteins with LMW (24.8,27.9 kDa) were completely lost in NaCl treatment. Moreover, these four protein spots were not observed in both protein profiles of cv. Ceyhan-99. Most of these proteins were in acidic character (pl <6.0,6.9) and low molecular weight (<31.6 kDa). It is suggested that the newly synthesized or completely lost LMW proteins may be important for cultivars differing in sensitivity towards NaCl. [source] Identification and composition of cuticular hydrocarbons of the major Afrotropical malaria vector Anopheles gambiae s.s. (Diptera: Culicidae): analysis of sexual dimorphism and age-related changes,JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 12 2005Beniamino Caputo Abstract Forty-eight cuticular hydrocarbons (CHCs) were characterized by gas chromatography-mass spectrometry from the epicuticular surface of the major Afrotropical malaria vector Anopheles gambiae. The hydrocarbons identified were 14 n -alkanes, 16 monomethyl alkanes, 13 dimethyl alkanes, 5 alkenes, with main-chain lengths ranging from C17 to C47, and the results are consistent with those from other Culicidae species. Qualitative differences were not observed between laboratory pools of three females and males, between different age-groups (0,16 days) and between single field specimens, whereas quantitative differences in CHC profiles were observed. Differences between sexes were more marked in individuals aged 0,2 days than in older ones. Both sexes undergo strong CHC profile changes with age, and individuals aged 0,2 days differ remarkably from the older ones. The possibility of exploiting these changes for estimating the age of mosquito was explored through multivariate analyses of the relative abundance of the compounds, using either the whole CHC profile or a subset of CHCs. Such a method allows us to assign more than 85% of females and 75% of males to the correct age-group. Although preliminary, these results show that the method is promising, as it has already been shown in Aedes aegypti and An. stephensi. The correct determination of the vector age (particularly in the case of the An. gambiae complex of sibling species) provides valuable information in malaria epidemiology and in evaluation of the effectiveness of vector control strategies. Further efforts will be made to validate this method on single specimens reared in seminatural conditions before being proposed to medical entomologists working in the Afrotropical region. Copyright © 2005 John Wiley & Sons, Ltd. [source] Cellular normalization of viral DNA loads on whole blood improves the clinical management of cytomegalovirus or Epstein Barr virus infections in the setting of pre-emptive therapyJOURNAL OF MEDICAL VIROLOGY, Issue 1 2009Céline Bressollette-Bodin Abstract Two quantitative duplex real-time PCR assays were developed for co-amplification of human albumin and cytomegalovirus (CMV) or Epstein Barr virus (EBV) genes after automated extraction on whole blood, and compared two units for expressing viral DNA loads (copies per ml of blood or per 106 peripheral blood leukocytes (PBLs)) on 1,138 positive samples. Both PCRs were characterized by high sensitivity, reproducibility, and linear range. Automated extraction by a MagNA Pure LC Instrument was shown to be more efficient when peripheral blood cell count was inferior to 5,×,109 PBLs/L. Albumin co-amplification allows the detection of PCR inhibitors and normalization of viral load according to the number of cells calculated in the sample. The two ways of expressing viral load results were highly correlated, but quantitative differences varied in relation to variations of blood cell count. As these two viruses are highly cell associated, viral loads can be underestimated in patients with leucopenia. In the setting of pre-emptive strategies during CMV infection, the units in which results are expressed can influence clinical management, as illustrated in this article. J. Med. Virol. 81:90,98, 2009. © 2008 Wiley-Liss, Inc. [source] Regulation and Expression of Progesterone Receptor mRNA Isoforms A and B in the Male and Female Rat Hypothalamus and Pituitary Following Oestrogen TreatmentJOURNAL OF NEUROENDOCRINOLOGY, Issue 3 2002R. E. M. Scott Abstract Progesterone receptors play a central role in neuroendocrine and behavioural regulation. To gain insight into the sex- and tissue-specific regulation of progesterone receptors, protein binding on a progesterone receptor-oestrogen response element and mRNA levels for progesterone receptor (PR)-A and PR-B were compared between female and male rats following oestradiol benzoate replacement treatment in hypothalamic and pituitary tissue. Both male and female pituitary protein extracts demonstrated an increase in nuclear protein binding activity to a progesterone receptor-oestrogen response element following oestradiol benzoate treatment. However, there was a greater difference in total binding activity seen in the female pituitary extracts compared to male pituitary protein extracts. In both cases, reflecting the binding data, oestradiol benzoate pretreatment led to an increase in pituitary PR-B messenger RNA, although this increase was significantly larger in females than in males. Oestradiol benzoate treatment also led to a significant increase in specific binding of hypothalamic nuclear proteins to the progesterone receptor oestrogen response element from both females and male hypothalamic extracts. In addition, PR-B messenger RNA was induced by oestradiol benzoate treatment in the female rat hypothalamus, under circumstances where no PR-A could be detected. The male also demonstrated an increase in PR-B messenger RNA following oestradiol benzoate treatment, with undetectable levels of PR-A, although to a lesser degree than that seen in the female. The predominance of PR-B over PR-A messenger RNA in rat hypothalamus and pituitary, and the quantitative differences between female and male rats, could both contribute to the greater responsiveness of female rats to progesterone with respect to control over luteinizing hormone release from the pituitary, and lordosis behaviour regulated by hypothalamic neurones. [source] Biocontrol and Plant Pathogenic Fusarium oxysporum -Induced Changes in Phenolic Compounds in Tomato Leaves and RootsJOURNAL OF PHYTOPATHOLOGY, Issue 7-8 2007Y. Panina Abstract The biocontrol fungus Fusarium oxysporum strain CS-20 was previously shown to reduce the incidence of Fusarium wilt of tomato through an uncharacterized host-mediated response. As phenolic compounds are involved in the defence response of tomato to pathogens and other stressors, this work was undertaken to determine whether biocontrol strains induced changes in phenolic compounds in leaves and roots of tomato seedlings in the presence and absence of pathogenic F. oxysporum f. sp. lycopersici. Roots of intact tomato seedlings were placed in water or aqueous fungal spore suspensions. Two biocontrol F. oxysporum strains [CS-20 (host-mediated mechanism) and 85SK-1 (control mechanism unknown)] and two plant pathogenic strains of F. oxysporum f. sp. lycopersici Race 1 were used. After 24 or 72 h exposure, phenolic compounds were extracted from leaves and roots before identification by HPLC. There were significant qualitative and quantitative differences between the two sampling times. Compared with the control treatment, strain CS-20 significantly altered (usually increasing) the ferulic, caffeic and vanillic acid contents, and concentrations once unidentified phenolic compounds recovered from leaves and roots. In another experiment, tomato seedlings growing in sterile sand were drenched with spores of strain CS-20 the day before treating them with varying concentrations of spores of the pathogen for 24 or 72 h. The amount of pathogen present did not significantly affect the plant phenolic response to the presence of strain CS-20. This work demonstrates that tomato responds within 24 h to the presence of the biocontrol strain CS-20 by alterations in secondary metabolism that are typical of resistance responses in tomato. [source] Quoting ethnicity: Constructing dialogue in Aotearoa/New Zealand1JOURNAL OF SOCIOLINGUISTICS, Issue 1 2010Alexandra D'Arcy Within the system of direct quotation, speakers have a number of resources at their disposal from which they can select to construct dialogue. This article presents an investigation of the ways in which Maori and Pakeha English speakers deploy these resources. The analysis reveals extensive differences in the construction of dialogue between Maori and Pakeha which include, but are not limited to, quantitative differences in the use of individual verbs of quotation. Distinct effects of tense/temporal reference and mimetic re-enactment permeate the systems, and patterns of use surrounding the zero quotative emerge as central to many points of differentiation. It is argued that these patterns form distinct strategies in the deployment of quotative resources and in this sense are indexical of ethnic identity in Aotearoa/New Zealand. [source] Fruit physical, chemical and aromatic attributes of early, intermediate and late apricot cultivarsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 6 2010Riccardo Lo Bianco Abstract BACKGROUND: In order to reach good fruit quality, apricots require a balance of sugars and acids as well as a strong apricot aroma. In this study, fruit quality of early, intermediate and late apricot cultivars was evaluated by measuring physical, chemical and olfactory attributes. Multivariate analysis of quality and aroma attributes was used to identify groups of similar cultivars and association with ripening season. RESULTS: Physical, chemical and aromatic attributes showed great variation among cultivars but no relation to ripening season. Aromatic profiles (34 volatiles) of fruit tissues indicated qualitative and quantitative differences among cultivars. Ninfa and Mandorlon were richest in aroma, with a prevailing fruity component; Goldrich and Orange Red were also highly aromatic, with all odour components well represented; Pinkot, Alba and Pellecchiella were lowest in aroma, with a prevailing grassy component. Linear functions including five volatiles (concentrations) and fruit diameter or six aromatic compounds (odour units) and peel colour were found to discriminate cultivars by ripening season. Principal component analysis individuated three groups of cultivars: Ninfa and Mandorlon with sweet and fruity-flavoured fruits; Bulida, Alba, Goldrich, Ouardy and Silvercot with large, acidic and well-coloured fruits; and Fracasso, Pellecchiella, Palummella and Pinkot with small and floral/grassy-flavoured fruits. CONCLUSION: In apricot, detailed analysis of the aromatic profile may represent an efficient tool for classification of genotypes by ripening season, and volatiles with relevant odour contribution may serve as quality markers for selecting towards an extended ripening season of best quality apricots. Copyright © 2010 Society of Chemical Industry [source] A comparison of the peel oil components of Australian native lime (Microcitrus australe) and Mexican lime (Citrus aurantifolia Swingle)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2005John D Craske Abstract The essential oil components extracted from the pericarp layer of two varieties of lime fruit, viz. Mexican lime (Citrus aurantifolia Swingle) and an Australian native lime (Microcitrus australe) have been analysed by gas chromatography/mass spectrometry. Thirty-three components were identified in M australe and 34 in C aurantifolia. The compound types comprised monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpenes and coumarins. For the more volatile monoterpenoid compounds, the major component was limonene, with significant amounts of ,-terpinene, ,-pinene, geranial, neral, neryl acetate and geranyl acetate. From an examination of the nature and contents of individual components, there was no indication that any one compound might be responsible for the predominant aroma impact. The possible contribution to aroma differences due to quantitative differences in the amounts of these components is discussed. However, sensory evaluation indicated that there was little or no difference between the aromas of the two oils. Copyright © 2004 Society of Chemical Industry [source] Comparative study on the proteolytic activities and storage globulins in seeds of Theobroma grandiflorum (Willd ex Spreng) Schum and Theobroma bicolor Humb Bonpl, in relation to their potential to generate chocolate-like aromaJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2004Christoph Reisdorff Abstract The cocoa relatives T grandiflorum (cupuaçu) and T bicolor (macambo) are promising crop plants for sustainable agroforestry in the Amazon region of South America. The market for cupuaçu is expanding since the fruit flesh is utilised by the foodstuffs industry. Attempts to commercialise chocolate-like wares from the seeds have failed so far because of unreliable product quality. It is not known whether this is due to an insufficient aroma potential of cupuaçu seeds. We therefore investigated the proteolytic enzymes and the seed storage globulins which are both decisive for the formation of aroma precursors in cocoa. We found that the activities of the aspartic endopeptidase and the carboxypeptidase in T bicolor and T grandiflorum differed slightly from those in cocoa. The specificity of the carboxypeptidase for hydrophobic amino acids was quite similar across the three species, while the optimal pH of the T grandiflorum enzyme was lower than that of the other species. The qualitative and quantitative differences between the globulins indicate a lower maximum yield of aroma precursors in T grandiflorum and a higher maximum yield of aroma precursors in T bicolor, compared to cocoa. We conclude that the quality of chocolate-like products made from the studied cocoa relatives can be improved by adapting fermentation procedures to particular biochemical features of these seeds. Copyright © 2004 Society of Chemical Industry [source] Comparative study of six pear cultivars in terms of their phenolic and vitamin C contents and antioxidant capacityJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 10 2003Andrea C Galvis Sánchez Abstract The main phenolic compounds in six pear cultivars were identified and quantified using high-performance liquid chromatography/diode array detection (HPLC/DAD) and HPLC/electrospray ionisation mass spectrometry (HPLC/ESIMS). Major quantitative differences were found in the phenolic profiles. The peel contained higher concentrations of chlorogenic acid, flavonols and arbutin than the flesh, where only chlorogenic acid was detected. Total phenolics ranged from 1235 to 2005 mg kg,1 in the peel and from 28 to 81 mg k g,1 in the flesh. Ascorbic acid and dehydroascorbic acid were detected in the peel, whereas only dehydroascorbic acid was present in the flesh. The ranges of vitamin C content were from 116 to 228 mg kg,1 in the peel and from 28 to 53 mg kg,1 in the flesh. The antioxidant capacity was correlated with the content of chlorogenic acid (r = 0.46), while ascorbic acid made only a small contribution to the total antioxidant capacity of the fruit. Copyright © 2003 Society of Chemical Industry [source] Divergence in gene expression related to variation in host specificity of an ectomycorrhizal fungusMOLECULAR ECOLOGY, Issue 12 2004ANTOINE LE QUÉRÉ Abstract Ectomycorrhizae are formed by mutualistic interactions between fungi and the roots of woody plants. During symbiosis the two organisms exchange carbon and nutrients in a specific tissue that is formed at the contact between a compatible fungus and plant. There is considerable variation in the degree of host specificity among species and strains of ectomycorrhizal fungi. In this study, we have for the first time shown that this variation is associated with quantitative differences in gene expression, and with divergence in nucleotide sequences of symbiosis-regulated genes. Gene expression and sequence evolution were compared in different strains of the ectomycorrhizal fungus Paxillus involutus; the strains included Nau, which is not compatible with birch and poplar, and the two compatible strains Maj and ATCC200175. On a genomic level, Nau and Maj were very similar. The sequence identity was 98.9% in the 16 loci analysed, and only three out of 1075 genes analysed by microarray-based hybridizations had signals indicating differences in gene copy numbers. In contrast, 66 out of the 1075 genes were differentially expressed in Maj compared to Nau after contact with birch roots. Thirty-seven of these symbiosis-regulated genes were also differentially expressed in the ATCC strain. Comparative analysis of DNA sequences of the symbiosis-regulated genes in different strains showed that two of them have evolved at an enhanced rate in Nau. The sequence divergence can be explained by a decreased selection pressure, which in turn is determined by lower functional constraints on these proteins in Nau as compared to the compatible strains. [source] Mechanisms of homology-facilitated illegitimate recombination for foreign DNA acquisition in transformable Pseudomonas stutzeriMOLECULAR MICROBIOLOGY, Issue 4 2003Petra Meier Summary Intra- and interspecific natural transformation has been observed in many prokaryotic species and is considered a fundamental mechanism for the generation of genetic variation. Recently, it has been described in detail how, in transformable Acinetobacter BD413 and Streptococcus pneumoniae, long stretches of nucleotides lacking homology were integrated into recipient genomes when they were linked on one side to a small piece of DNA with homology to resident DNA serving as a recA -dependent recombination anchor. Now, such homology-facilitated illegitimate recombination (HFIR) has also been detected in transformable Pseudomonas stutzeri. However, analysis of the recombinants revealed qualitative and quantitative differences in their generation compared with that in Acinetobacter BD413. In P. stutzeri, foreign DNA with an anchor sequence was integrated 105 - to 106 -fold less frequently than fully homologous DNA, but still at least 200-fold more frequently than without the anchor. The anchor sequence could be as small as 311 bp. Remarkably, in 98% of the events, the 3, end was integrated within the homologous anchor, whereas the 5, end underwent illegitimate fusion. Moreover, about one-third of the illegitimate fusion sites shared no or only a single identical basepair in foreign and resident DNA. The other fusions occurred within microhomologies of up to 6 bp with a higher GC content on average than the interacting nucleotide sequences. Foreign DNA of 69,1903 bp was integrated, and resident DNA of 22,2345 bp was lost. In a recA mutant, HFIR was not detectable. The findings suggest that genomic acquisition of foreign DNA by HFIR during transformation occurs widely in prokaryotes, but that details of the required recombination and strand fusion mechanisms may differ between organisms from different genera. [source] | ||||||||||||||||||||||||||||||||||