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Major Constituents (major + constituent)
Selected AbstractsThe Eye Irritation and Odor Potencies of Four Terpenes which are Major Constituents of the Emissions of VOCs from Nordic Soft WoodsINDOOR AIR, Issue 4 2000L. MØLHAVE [source] Chemical composition of essential oils from aerial parts of Cinnamomum malabatrum (Burman f.) Bercht & Presl.FLAVOUR AND FRAGRANCE JOURNAL, Issue 1 2009N. K. Leela Abstract The constituents of the essential oils of leaf, petiole, shoot and terminal shoot of Cinnamomum malabatrum were determined by GC and GC,MS. Thirty-nine compounds, constituting 95% of the oil, were identified in the leaves. Major constituents of the leaf oil were (E)-caryophyllene (28.6%), (E)-cinnamyl acetate (15.1%), bicyclogermacrene (14.4%) and benzyl benzoate (8.5%). Twenty-eight compounds, representing 98% and 97% of the oil, were identified in the petioles and shoots, respectively, whereas in the oil of the terminal shoots 34 compounds, accounting for 97%, were identified. The essential oils of the petioles, shoots and terminal shoots were dominated by linalool (77.8,79.4%). This is the first report of the essential oil constituents of C. malabatrum. Copyright © 2008 John Wiley & Sons, Ltd. [source] The essential oil composition of Acroptilon repens (L.) DC. of Turkish originFLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2006Zeynep Tunalier Abstract The composition of essential oil obtained from the aerial parts of Russian knapweed [Acroptilon repens (L.) DC.] (Asteraceae) was analyzed by GC and GC-MS. Seventy-two components were identified in the essential oil of Acroptilon repens (L.) DC. Major constituents of the essential oil were , -copaene (22.8%), , -caryophyllene (9.5%), germacrene D (9.0%), , -cubebene (7.9%) and caryophyllene oxide (6.4%). Copyright © 2006 John Wiley & Sons, Ltd. [source] Essential oil composition of Pimpinella aurea D.C. from IranFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2005F. Askari Abstract Essential oils were isolated by hydrodistillation from the stems, ,owers and seeds of Pimpinella aurea D.C. They were collected individually from Fasham (north-west of Tehran province). The yields of stem + leaf, ,ower and seed oils were 0.4%, 1.5% and 2.0% w/w, respectively; 32 constituents were identi,ed in the stem + leaf oil, 18 in the ,ower oil and eight in the seed oil. Major constituents of the stem + leaf oil were: 1,8-cineol and limonene (21.4%), viridi,orol (12.8%), , -pinene (11.5%), kessane (10.5%), germacrene D (4.9%), , -bisabolene (4.2%), , -zingiberene (3.3%) and citronellyl acetate (3.1%). Major constituents of the ,ower oil were: viridi,orol (32.5%), , -bisabolene (29.5%), caryophyllene oxide (6.6%), 1,8-cineol + limonene (8.9%) and estragol (5.1%). Major constituents of the seed oil were: , -bisabolene (50.8%), and viridi,orol (37.0%). Three compounds (, -bisabolene, viridi,orol and caryophyllene oxide) were common to all three oils. 1,8-Cineol and limonene, kessane and , -pinene were the major compounds in the stem + leaf and ,ower oils but were not found in the seed oil. Copyright © 2004 John Wiley & Sons, Ltd. [source] Requirement of phospholipase C-,2 (PLC,2) for Dectin-1-induced antigen presentation and induction of TH1/TH17 polarizationEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 5 2009Ilaria Tassi Abstract DC recognize microbial components through an array of receptors known as PRR. PRR initiate intracellular signals, which engender DC with the capacity to stimulate T-cell responses. Dectin-1 is a PRR that recognizes ,-glucan, a major constituent of many fungi's outer cell wall. Here we show that Dectin-1 activates DC through phospholipase (PLC),2 signaling. PLC,2-deficient DC were unable to expand antigen-specific T cells and induce TH1 and TH17 differentiation in response to ,-glucan. Mechanistically, PLC,2-deficiency impaired the capacity of DC to secrete polarizing cytokines following exposure to ,-glucan. Dectin-1 required PLC,2 to activate MAPK, AP-1 and NF-,B, which induce cytokine gene expression. Moreover, PLC,2 controlled Dectin-1-mediated NFAT activation and induction of NFAT-dependent genes such as IL-2, cyclooxigenase-2 and Egr transcription factors. We conclude that PLC,2 is a crucial signaling mediator that modifies DC gene expression program to activate DC responses to ,-glucan-containing pathogens. [source] Antioxidant properties of extracts and compounds from Psoralea morisianaEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7-8 2005Antonella Rosa Abstract The antioxidant activity of various extracts (MeOH, petroleum ether, EtOAc) from the aerial parts of Psoralea morisiana, an endemic Sardinian plant, was evaluated during autoxidation and iron-mediated oxidation of linoleic acid at 37,°C and during cholesterol oxidation at 140,°C, in the absence of solvent. The activity of erybraedin,C, bitucarpin,A and plicatin,B, isolated from the extracts, was investigated under the same experimental conditions and compared to that of BHT and ,-tocopherol. All the extracts, erybraedin,C (major constituent of the extracts) and plicatin,B showed powerful antioxidant properties. None of the extracts and pure compounds showed any prooxidant activity. The cytotoxicity of the extracts, erybraedin,C, and plicatin,B was further evaluated in VERO cells, a line of fibroblasts derived from monkey kidney. Erybraedin,C, at non-cytotoxic concentrations, showed a strong inhibition of FeCl3 -induced oxidation in VERO cells. [source] Calcite-specific coupling protein in barnacle underwater cementFEBS JOURNAL, Issue 24 2007Youichi Mori The barnacle relies for its attachment to underwater foreign substrata on the formation of a multiprotein complex called cement. The 20 kDa cement protein is a component of Megabalanus rosa cement, although its specific function in underwater attachment has not, until now, been known. The recombinant form of the protein expressed in bacteria was purified in soluble form under physiological conditions, and confirmed to retain almost the same structure as that of the native protein. Both the protein from the adhesive layer of the barnacle and the recombinant protein were characterized. This revealed that abundant Cys residues, which accounted for 17% of the total residues, were in the intramolecular disulfide form, and were essential for the proper folding of the monomeric protein structure. The recombinant protein was adsorbed to calcite and metal oxides in seawater, but not to glass and synthetic polymers. The adsorption isotherm for adsorption to calcite fitted the Langmuir model well, indicating that the protein is a calcite-specific adsorbent. An evaluation of the distribution of the molecular size in solution by analytical ultracentrifugation indicated that the recombinant protein exists as a monomer in 100 mm to 1 m NaCl solution; thus, the protein acts as a monomer when interacting with the calcite surface. cDNA encoding a homologous protein was isolated from Balanus albicostatus, and its derived amino acid sequence was compared with that from M. rosa. Calcite is the major constituent in both the shell of barnacle base and the periphery, which is also a possible target for the cement, due to the gregarious nature of the organisms. The specificity of the protein for calcite may be related to the fact that calcite is the most frequent material attached by the cement. [source] Rough and smooth forms of fluorescein-labelled bacterial endotoxin exhibit CD14/LBP dependent and independent binding that is influencedby endotoxin concentrationFEBS JOURNAL, Issue 8 2000Martha Triantafilou Lipopolysaccharide (LPS, or endotoxin), is a major constituent of the outer membrane of Gram-negative bacteria. Bacteria express either smooth LPS, which is composed of O-antigen (O-Ag), complete core oligosaccharides, and the lipid A, or rough LPS which lack O-Ag but possess lipid A and progressively shorter core oligosaccharides. CD14 has been described as the receptor for complexes of LPS with LPS-binding protein (LBP). Using flow cytometry we have compared the binding of Salmonella minnesota rough LPS (ReLPS) and Escherichia coli smooth LPS labelled with fluorescein isothiocyanate (FITC-LPS) to Chinese hamster ovary (CHO) cells transfected with human CD14 gene (hCD14-CHO), to MonoMac 6 cells and to endothelial cells. Our results showed that both forms of LPS display the same binding characteristics, and that the binding of FITC-LPS to cells was both CD14- and LBP-dependent for LPS concentrations up to 100 ng·mL,1. At LPS concentrations higher than 100 ng·mL,1 we observed CD14/LBP-independent binding. CD14/LBP-dependent binding was dose dependent, saturable, and enhanced in the presence of human pooled serum (HPS), and the monoclonal anti-CD14 antibody (MY4) or unlabelled LPS could outcompete it. [source] Essential oil composition of Pimpinella affinis Ledeb. from two localities in IranFLAVOUR AND FRAGRANCE JOURNAL, Issue 5 2006F. Askari Abstract Essential oils were isolated by hydrodistillation from the stems plus leaves, inflorescences and seeds of Pimpinella affinis Ledeb. individually. The plants were collected from Khojir and Chaloos (north-east and north of Tehran province, respectively). The yields of stem plus leaf, inflorescence and seed oils for the Khojir samples were 0.04%, 1.98% and 5.33% w/w and for the Chalous samples were 0.37%, 1.74% and 4.05% w/w, respectively. Limonene is a major constituent in the inflorescence and seed oils of the Khojir (47.9% and 90.5%, respectively) and Chalous samples (37.8% and 70.8%, respectively), whereas it was found in the stem plus leaf oil of the Khojir and the Chalous samples in low amounts (1.4% and 0.8%, respectively). , -Terpinen-7-al is the major constituent in the stem plus leaf and inflorescence oils of the Khojir (69.9% and 37.6%) and Chalous samples (72.8% and 49.1%), but was not found at all in the seed oils. Caryophyllene oxide (9.1%) was found in the stem plus leaf oil of the Khojir sample, and methyl eugenol (9.7%) and (E)-nerolidol acetate (9.1%) in the seed oil of the Chalous sample. Copyright © 2006 John Wiley & Sons, Ltd. [source] Determination of essential oil quality index by using energy summation indices in an elite strain of Cymbopogon citratus (DC) Stapf [RRL(J)CCA12]FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2005Ashok Kumar Shahi Abstract Out of the several accessions of Cymbopogon citratus (DC) Stapf introduced from Central and West India, one accession coded as RRL(J)CCA12, selected through a mass selection technique, was found to have citral (,80%) as the major constituent in its essential oil. Citral has tremendous application in the ,avour and perfume industries. Plant adaptation was judged by quantifying the regression coef,cient (b) value, which was 1.0 using essential oil growth indices. For prediction of essential oil quality index (EOQI), a multiple regression equation was developed for the ,rst time by using essential oil yield/plant and energy summation indices as EOQI (citral %) = 61.6 + 1.09 × essential oil yield/plant (g) - 0.005 × heat use ef,ciency + 0.675 × phenothermal index. For obtaining a better quality of essential oil (citral ,78%), the optimal value of independent variable would be: X1 = 2.49; X2 = 0.018 and X3 = 20.47, where X1, X2 and X3 denote essential oil yield/plant, heat use ef,ciency and phenothermal index, respectively. The validation of the EOQI model is done by correlating the predicted and calculated values of citral (%) which exhibited signi,cant r value = 0.955 at 5% probability level. The thermal requirement of the selectant was ,5500 degree days to exhibit plant maturity in terms of qualitative and quantitative characteristics of its essential oil at 6.0 vegetative lea,ng stage, with attainment of plant height ,1.0 m from previous date of harvest (December 2001). Prediction of essential oil quality by using the mathematical model is helpful for integrating the growth processes and evaluating crop management strategies. Copyright © 2004 John Wiley & Sons, Ltd. [source] Study of essential oils of Eucalyptus resinifera Smith, E. tereticornis Smith and Corymbia maculata (Hook.) K. D. Hill & L. A. S. Johnson, grown in CubaFLAVOUR AND FRAGRANCE JOURNAL, Issue 1 2002Jorge A. Pino Abstract The yields and chemical composition are reported of oils obtained by hydrodistillation from the leaves of three species grown in the western region of Cuba: Eucalyptus resinifera Smith, Eucalyptus tereticornis Smith and Corymbia maculata (Hook.) K. D. Hill & L. A. S. Johnson. The analyses were made by GC and GC,MS. The oil of E. resinifera was found to contain 1,8-cineole (68.0%) as the major constituent. In contrast, the oil of E. tereticornis was found to contain 1,8-cineole (23.2%) and p - cymene (13.8%), while that of C. maculata contained ,-pinene (49.7%), ,-eudesmol (18.0%) and ,-eudesmol (11.3%) as major constituents. Copyright © 2001 John Wiley & Sons, Ltd. [source] Essential oil constituents of Melia dubia, a wild relative of Azadirachta indica growing in the Eastern Ghats of Peninsular IndiaFLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2001M. A. H. Nagalakshmi Abstract The leaf essential oil of Melia dubia Cav. (Meliaceae) has been studied by GC,MS. The leaf essential oil consists chiefly of monoterpenes (35.71%) and oxygenated monoterpenes (27.98%), accompanied by a relatively much smaller amount of alkanes (11.17%), sesquiterpene hydrocarbons (9.26%) and phenylpropanoids (3.90%). The monoterpene camphene occurs as a major constituent (21.68%) of this leaf essential oil. It is accompanied by a noticeable amount of ,- and ,-pinene (3.12% and 5.13%, respectively) and a much smaller amount of sabinene (2.75%). The oxygenated monoterpenes are distinctly dominated by the presence of the bicyclic ketone camphor (17.85%), while iso-borneol and borneol are detected in much smaller amounts (4.15% and 1.12%, respectively). Copyright © 2001 John Wiley & Sons, Ltd. [source] Beta-2-Microglobulin in nocturnal hemodialysis , A comparative study in low and high flux dialysersHEMODIALYSIS INTERNATIONAL, Issue 1 2005A.B. Reid In end-stage renal failure, impaired renal catabolism leads to retention of beta 2 microglobulin (ß2M), identified as the major constituent of hemodialysis (HD) related amyloidosis. It has been previously shown that, while using a high flux (HF) HD membrane, nocturnal hemodialysis (NHD) with its increased time and frequency provides a much higher clearance of ß2M compared to conventional HD. We compared serum ß2M levels between low flux (LF) and HF in a group of 9 NHD patients who dialyse 8 hours 6 nights/week. Fresenius polysulfone LF membrane size F6-F8 HPS dialyser were used for the first 15 months (mth) of NHD (SA 1.3,1.8 m2). Subsequently, polysulfone HF FX80 dialyzer were used (SA 1.8 m2). Blood flow and dialysate flow rates were unchanged throughout the study. ß2M levels were measured at 6, 12, 15 mth on LF and at 6, 12 mth on HF. Albumin, homocysteine (Hcy), and phosphate (Phos) levels were also recorded at these times. ß2M levels trended upwards during the 15 mth on LF (36.6 ± 10.57 at 6 mth vs 47.1 ± 11.7 at 15 mth). On introduction of HF, there was a significant fall in ß2M at 6 mth to 12.4 ± 3.5 (p < 0.003), while ß2M levels were unchanged at 12 mth of HF. A downward trend in Hcy levels with the use of HF was noted (12.9 ± 2.9 at 0 mth Vs 11.1 ± 3.7 at 12 mth). Plasma albumin and Phos levels remained unchanged as did the use of Phos supplementation. Levels of ß2M continued to rise on NHD with LF, indicating inadequate clearance. With the introduction of HF there was a significant fall in ß2M levels consistent with improved clearance. The implications of this are that ß2M clearance may be time and frequency dependent only if dialyser membrane flux is adequate. [source] Characterisation of oregano water extracts and their effect on the quality characteristics of cooked porkINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 2 2009Jonas Dama Summary The present study characterises oregano water extracts and reports their effects on the shelf life and quality characteristics of cooked pork. Some changes in oregano extract taking place during its thermal treatment were observed. The main volatile compound in the unheated and heated extracts was carvacrol; however, the second major constituent in the unheated extract ,-caryophyllene was absent in the heated one. Colour changes during heating were characterised by an International Commission on Illumination (CIE L a b) method. The heated extract better scavenged 1,1-diphenyl-2-picryl hydrazyl radicals, most likely owing to the formation of stronger radical-scavenging derivatives during thermal treatment. The effect of oregano extracts on the shelf life and colour characteristics of stored meat samples in most cases was not significant; however, sensory assessment clearly showed that the addition of extracts had some negative influence on meat flavour and colour. [source] An extract of Apium graveolens var. dulce leaves: structure of the major constituent, apiin, and its anti-inflammatory propertiesJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 6 2007T. Mencherini Flavonoids, natural compounds widely distributed in the plant kingdom, are reported to affect the inflammatory process and to possess anti-inflammatory as well as immunomodulatory activity in-vitro and in-vivo. Since nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) is one of the inflammatory mediators, the effects of the ethanol/water (1:1) extract of the leaves of Apium graveolens var. dulce (celery) on iNOS expression and NO production in the J774.A1 macrophage cell line stimulated for 24 h with Escherichia coli lipopolysaccharide (LPS) were evaluated. The extract of A. graveolens var. dulce contained apiin as the major constituent (1.12%, w/w, of the extract). The extract and apiin showed significant inhibitory activity on nitrite (NO) production in-vitro (IC50 0.073 and 0.08 mg mL,1 for the extract and apiin, respectively) and iNOS expression (IC50 0.095 and 0.049 mg mL,1 for the extract and apiin, respectively) in LPS-activated J774.A1 cells. The croton-oil ear test on mice showed that the extract exerted anti-inflammatory activity in-vivo (ID50 730 ,g cm,2), with a potency seven-times lower than that of indometacin (ID50 93 ,g cm,2), the non-steroidal anti-inflammatory drug used as reference. Our results clearly indicated the inhibitory activity of the extract and apiin in-vitro on iNOS expression and nitrite production when added before LPS stimulation in the medium of J774.A1 cells. The anti-inflammatory properties of the extract demonstrated in-vivo might have been due to reduction of iNOS enzyme expression. [source] Late Quaternary vegetation changes around Lake Rutundu, Mount Kenya, East Africa: evidence from grass cuticles, pollen and stable carbon isotopesJOURNAL OF QUATERNARY SCIENCE, Issue 1 2003Dr M. J. Wooller Abstract Woody, subalpine shrubs and grasses currently surround Lake Rutundu, Mount Kenya. Multiple proxies, including carbon isotopes, pollen and grass cuticles, from a 755-cm-long core were used to reconstruct the vegetation over the past 38 300 calendar years. Stable carbon-isotope ratios of total organic carbon and terrestrial biomarkers from the lake sediments imply that the proportion of terrestrial plants using the C4 photosynthetic pathway was greater during the Late Pleistocene than in the Holocene. Pollen data show that grasses were a major constituent of the vegetation throughout the Late Pleistocene and Holocene. The proportion of grass pollen relative to the pollen from other plants was greatest at the last glacial maximum (LGM). Grass cuticles confirm evidence that C4 grass taxa were present at the LGM and that the majority followed the cold-tolerant NADP-MEC4 subpathway. Copyright © 2003 John Wiley & Sons, Ltd. [source] Genomic origin, processing and developmental expression of testicular outer dense fiber 2 (ODF2) transcripts and a novel nucleolar localization of ODF2 proteinMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 11 2008Eugene Rivkin Abstract Outer dense fibers are a major constituent of the sperm tail and outer dense fiber 2 (ODF2) protein is one of their major components. ODF2 shares partial homology with cenexin 1 and cenexin 2, regarded as centriolar proteins. We show that ODF2 and cenexin 2 transcripts are the product of differential splicing of a single gene, designated Cenexin/ODF2 and that cenexin 1 is an incomplete clone of ODF2. ODF2 terminates in exon 20b whereas in cenexin 2 this exon is spliced out and translation terminates in exon 24. We demonstrate a transcriptional switch during rat testicular development, from somatic-type to testis-type ODF2 and cenexin transcripts during the onset of meiosis. The switch is completed when spermiogenesis is established. ODF2 immunoreactive sites were visualized in the acroplaxome, along the sperm tail and the centrosome-derived sperm head-to-tail coupling apparatus. An unexpected finding was the presence of ODF2 antigenic sites, but not cenexin antigenic sites, in the dense fibrillar component of the nucleolus of Sertoli cells, spermatogonia and primary spermatocytes. The characterization of the genomic origin, processing and developmental expression of ODF2 transcript isoforms and their protein products can help reconcile differences in the literature on the role of ODF2 and cenexin in the centrosome. Furthermore, the finding of ODF2 in the dense fibrillar component of the nucleolus suggests that this protein, in addition to its presence in sperm outer dense fibers and centrosome, highlights and adds to the nucleolar function during spermatogenesis and early embryogenesis. Mol. Reprod. Dev. 75: 1591,1606, 2008. © 2008 Wiley-Liss, Inc. [source] Clinical entity of frontotemporal dementia with motor neuron diseaseNEUROPATHOLOGY, Issue 6 2009Yoshio Mitsuyama Non-Alzheimer-type dementias occur in association with a variety of pathological conditions that include a group of diseases characterized by atrophy of the frontal and temporal lobes. Frontotemporal dementia (FTD) is a clinical entity that comprises at least two distinct diseases: Pick's disease with Pick bodies and frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U). The vast majority of FTLD-U is now referred to as FTLD-TDP, following the recent discovery of TAR DNA-binding protein of 43 kDa (TDP-43) as the major constituent of the ubiquitin-positive inclusions. FTLD-TDP, but not Pick's disease with Pick bodies, is often associated with motor neuron disease (MND). MND is a group of diseases in which the central nervous system lesions were long believed to be confined to the motor neuron system. In other words, MND was not considered to be associated with other neurological symptoms such as dementia. Nevertheless, more than 200 FTD cases associated with clinical MND have been reported in Japan since 1964. Neuropathologically, MND in such FTD cases was essentially similar to MND in cases without dementia. The combination of FTD and MND was so characteristic that we considered these cases comprise a unique clinicopathological subgroup of FTD. FTD with MND and the classical MND without dementia share the occurrence of ubiquitinated TDP-43-positive inclusions, a finding that could be a key to unlock the pathological backgrounds of both diseases. [source] Composition of volatiles of banana cultivars from Madeira IslandPHYTOCHEMICAL ANALYSIS, Issue 2 2003J. M. F. Nogueira Abstract The composition of the volatiles of banana fruit from various cultivars grown on Madeira Island has been determined. Using GC-MS, the volatiles were shown to be complex mixtures of several classes of components, mainly esters, alcohols, aldehydes, ketones and acids. The average contents of the total volatiles from cultivars "Dwarf Cavendish", "Giant Cavendish", "Robusta" and "Williams" were 93.0, 116.5, 157.3 and 157.0,mg/kg, respectively. The ester and alcoholic fractions appear to play a decisive role in the organoleptic characteristics of banana fruit, presenting a substantial content ranging from 57.2 to 89.8,mg/kg and 19.0 to 47.7,mg/kg, respectively, in all cultivars from Madeira Island studied. 3-Methyl butyl butanoate ester was the major constituent. Copyright © 2003 John Wiley & Sons, Ltd. [source] A 15N-aided artificial atmosphere gas flow technique for online determination of soil N2 release using the zeolite Köstrolith SX6®RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 22 2006Oliver Spott N2 is one of the major gaseous nitrogen compounds released by soils due to N-transformation processes. Since it is also the major constituent of the earth's atmosphere (78.08% vol.), the determination of soil N2 release is still one of the main methodological challenges with respect to a complete evaluation of the gaseous N-loss of soils. Commonly used approaches are based either on a C2H2 inhibition technique, an artificial atmosphere or a 15N-tracer technique, and are designed either as closed systems (non-steady state) or gas flow systems (steady state). The intention of this work has been to upgrade the current gas flow technique using an artificial atmosphere for a 15N-aided determination of the soil N2 release simultaneously with N2O. A 15N-aided artificial atmosphere gas flow approach has been developed, which allows a simultaneous online determination of N2 as well as N2O fluxes from an open soil system (steady state). Fluxes of both gases can be determined continuously over long incubation periods and with high sampling frequency. The N2 selective molecular sieve Köstrolith SX6® was tested successfully for the first time for dinitrogen collection. The presented paper mainly focuses on N2 flux determination. For validation purposes soil aggregates of a Haplic Phaeozem were incubated under aerobic (21 and 6 vol.% O2) and anaerobic conditions. Significant amounts of N2 were released only during anaerobic incubation (0.4 and 640.2,pmol N2 h,1,g,1 dry soil). However, some N2 formation also occurred during aerobic incubation. It was also found that, during ongoing denitrification, introduced [NO3], will be more strongly delivered to microorganisms than the original soil [NO3],. Copyright © 2006 John Wiley & Sons, Ltd. [source] Correction of the CF defect by curcumin: hypes and disappointmentsBIOESSAYS, Issue 1 2005Marcus Mall Cystic fibrosis (CF), the most-common lethal hereditary disease in the white population, is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The mutation that is most frequently responsible for the disease, ,F508, causes misfolding and retention of the CFTR protein in the endoplasmic reticulum. This leads to a series of cellular dysfunctions and results in a multi-organ disease. In a recent report, Egan et al.1 demonstrated that curcumin, a non-toxic natural product and major constituent of turmeric spice, corrected the CF defects in ,F508 CF mice. This paper aroused a lot of attention and hopes were raised that curcumin might produce similar effects in human, giving an efficient treatment for most CF patients. However, skepticism is growing since subsequent studies fail to reproduce these initial exciting results. Thus, although herbal medicines and dietary supplements can be desirable alternatives to classical pharmacological compounds, their efficacy needs careful evaluation both in vivo and ex vivo. BioEssays 27:9,13, 2005. © 2004 Wiley Periodicals, Inc. [source] Thiophilic interaction chromatography of Alzheimer's , -amyloid peptidesCHEMICAL BIOLOGY & DRUG DESIGN, Issue 2005S. Parry Abstract:, Alzheimer's disease is characterized by a progressive formation of senile plaques in the brain, the major constituent of which is , -amyloid (A,) peptide, a proteolytic product of the transmembrane , -amyloid precursor protein (APP). Prior to the measurement of levels of the A, peptide for diagnostic purposes, this peptide must be isolated from the myriad of proteins resident in the human serum. Thiophilic interaction chromatography is an effective method for the isolation of proteins and peptides containing clusters of aromatic residues such as tryptophan, phenylalanine and tyrosine. The purpose of the present study was to develop a protocol for binding and recovery of A, peptides (1,38), (1,40) and (1,42) to T-gels by varying T-gel type and elution conditions such as the salt concentration and type of eluent. We established the minimal salt concentration necessary for the binding of the A,(1,40) peptide to the 3S-gel; binding at that concentration was subsequently compared with that of model proteins, lysozyme and , -chymotrypsin and this methodology was extended to 2S-gels and PyS. , -Amyloid peptide (1,40) showed a remarkably strong affinity for all three types of T-gels in comparison to lysozyme and , -chymotrypsin and was found to bind best to 2S-gel. [source] Highly Potent Modulation of GABAA Receptors by Valerenic Acid DerivativesCHEMMEDCHEM, Issue 5 2010Sascha Kopp Dipl.-Chem. Traditional medicine to potent drug leads: Valerenic acid (1) is a major constituent of common valerian and potentiates the effect of ,-aminobutyric acid on GABAA receptors. Through systematic modification of the carboxyl group of 1 we have discovered a noncarboxylate-containing analogue, tetrazole 10, which exceeds the modulatory activity of 1 at GABAA receptors by one order of magnitude. [source] Rare variations of the left subclavian arteryCLINICAL ANATOMY, Issue 5 2005Faysal A. Saadeh Abstract The subclavian artery is a major constituent of the blood circulatory system. Its position in the root of the neck and its course through the interscalene triangle are significant. Its branches supply divers areas in the body from the brain to the thorax. This case report describes an unusual range of anatomical variations of the course of the left subclavian artery, the origin, and absence of some of its branches and the concomitant abnormal course of the phrenic nerve. Clinical syndromes related to certain variations are reviewed. Clin. Anat. 18:370,372, 2005. © 2005 Wiley-Liss, Inc. [source] PROTECTIVE EFFECTS OF ICARIIN ON COGNITIVE DEFICITS INDUCED BY CHRONIC CEREBRAL HYPOPERFUSION IN RATSCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 8 2009Rui-Xia Xu SUMMARY 1Icariin is a major constituent of flavonoids derived from the Chinese medicinal herb Epimedium revicornum Maxim. The aim of the present study was to investigate whether icariin has protective effects on learning ability and memory in a rat model of chronic cerebral hypoperfusion. 2Chronic cerebral hypoperfusion was induced by permanent ligation of the common carotid artery in Wistar rats for 4 months. One month after permanent artery occlusion, rats were adminitered icariin at doses of 0, 30, 60 or 120 mg/kg per day, p.o., for 3 months. Neurobehavioural and neurobiochemical parameters were examined to evaluate the effects of icariin on cognitive deficits induced by chronic cerebral hypoperfusion. 3The Morris water maze test revealed that learning ability and memory were severely impaired in untreated rats, but were significantly improved in icariin-treated rats. Icariin treatment also ameliorated chronic cerebral hypoperfusion-induced oxidative stress in the brain, as evidenced by reduced malondialdehyde formation and maintained superoxide dismutase activity. In addition, the decreased hippocampal levels of acetylcholine, acetylcholinesterase and choline acetyltransferase associated with chronic cerebral hypoperfusion were significantly prevented by icariin treatment. 4In conclusion, icariin protects against cognitive deficits induced by chronic cerebral hypoperfusion in rats. These effects appear to be mediated through its anti-oxidant effects, as well as its effects on the circulatory and cholinergic systems. [source] The role of matrix metalloproteinases -9 and -2 in development of neonatal chronic lung diseaseACTA PAEDIATRICA, Issue 6 2004DG Sweet Aim: Matrix metalloproteinases (MMPs) -9 and -2 degrade type-IV collagen, a major constituent of lung basement membrane, and may have a role in the pathogenesis of neonatal chronic lung disease (CLD). We determined factors influencing MMP levels in neonatal bronchoalveolar lavage (BAL) fluid to establish whether an imbalance between MMP and its inhibitor could be implicated in CLD. Methods: We measured MMP-9 and -2 and tissue inhibitor of metalloproteinase-1 (TIMP-1) levels in 316 BAL fluid samples from 121 babies of gestational ages 23 to 42 wk over the first 14 d of life to determine effects of gestation and postnatal age. Median MMP-9, -2, TIMP-1 and MMP-9/TIMP-1 ratio in BAL were further studied in a subgroup of 85 babies >33 wk gestation to determine their ability to predict CLD and to establish effects of antenatal corticosteroid therapy (ANCS). Results: MMP-9, -2 and TIMP levels did not vary with postnatal age over the first week. Median MMP-9 levels and MMP-9/TIMP-1 ratio increased with decreasing gestation in preterm babies. The MMP-9/TIMP-1 ratio was higher in babies who developed CLD, implying a proteinase/antiproteinase imbalance, but this association disappeared when controlled for gestational age. ANCS had no effect on BAL fluid MMP or TIMP levels. Conclusion: MMPs may have a role in the development of lung injury and fibrosis, but estimating their levels in the first week of life does not help with prediction of CLD. [source] Abnormal myelin formation in rhizomelic chondrodysplasia punctata type 2 (DHAPAT-deficiency)DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 7 2000László Sztriha MD PhD The case of a Yemeni girl with isolated peroxisomal acyl-CoA:dihydroxyacetonephosphateacyltransferase (DHAPAT) deficiency is reported. She had rhizomelic chondrodysplasia punctata, microcephaly, failure to thrive, delayed motor and mental development, and spastic quadriplegia. Deficient de novo plasmalogen synthesis in her fibroblasts as a result of low DHAPAT activity was found, while her very-long-chain fatty acid profile, phytanic acid concentration, alkyl-dihydroxyacetonephosphate synthase (alkyl-DHAP synthase) activity, and peroxisomal 3-ketoacyl-CoA thiolase protein were normal. A mutation in her DHAPAT complementary DNA resulted in the substitution of an arginine residue in the protein at position 211 by a histidine (R211H). Magnetic resonance imaging showed abnormal white matter signal in the centrum semiovale involving the arcuate fibers, while the corpus callosum was normal. DHAPAT and alkyl-DHAP synthase initiate the synthesis of plasmalogens, which are major constituents of myelin phospholipids. The reported girl's abnormal formation of myelin is probably related to the inadequacy of plasmalogen biosynthesis, which is likely to be due to deficient DHAPAT activity. [source] Major components of a sea urchin block to polyspermy are structurally and functionally conservedEVOLUTION AND DEVELOPMENT, Issue 3 2004Julian L. Wong Summary One sperm fusing with one egg is requisite for successful fertilization; additional sperm fusions are lethal to the embryo. Because sperm usually outnumber eggs, evolution has selected for mechanisms that prevent this polyspermy by immediately modifying the egg extracellular matrix. We focus here on the contribution of cortical granule contents in the sea urchin block to polyspermy to begin to understand how well this process is conserved. We identified each of the major constituents of the fertilization envelope in two species of seaurchins, Strongylocentrotus purpuratus and Lytechinus variegatus, that diverged 30 to 50 million years ago. Our results show that the five major structural components of the fertilization envelope, derived from the egg cortical granules, are semiconserved. Most of these orthologs share sequence identity and encode multiple low-density lipoprotein receptor type A repeats or CUB domains but at least two contain radically different carboxy-terminal repeats. Using a new association assay, we also show that these major structural components are functionally conserved during fertilization envelope construction. Thus, it seems that this population of female reproductive proteins has retained functional motifs while gaining significant sequence diversity,two opposing paths that may reflect cooperativity among the proteins that compose the fertilization envelope. [source] Microfibril-associated glycoprotein-1 binding to tropoelastinFEBS JOURNAL, Issue 14 2004Multiple binding sites, the role of divalent cations Microfibrils and elastin are major constituents of elastic fibers, the assembly of which is dictated by multimolecular interactions. Microfibril-associated glycoprotein-1 (MAGP-1) is a microfibrillar component that interacts with the soluble elastin precursor, tropoelastin. We describe here the adaptation of a solid-phase binding assay that defines the effect of divalent cations on the interactions between MAGP-1 and tropoelastin. Using this assay, a strong calcium-dependent interaction was demonstrated, with a dissociation constant of 2.8 ± 0.3 nm, which fits a single-site binding model. Manganese and magnesium bestowed a weaker association, and copper did not facilitate the protein interactions. Three constructs spanning tropoelastin were used to quantify their relative contributions to calcium-dependent MAGP-1 binding. Binding to a construct spanning a region from the N-terminus to domain 18 followed a single-site binding model with a dissociation constant of 12.0 ± 2.2 nm, which contrasted with the complex binding behavior observed for fragments spanning domains 17,27 and domain 27 to the C-terminus. To further elucidate binding sites around the kallikrein cleavage site of domains 25/26, MAGP-1 was presented with constructs containing C-terminal deletions within the region. Construct M1659, which spans a region from the N-terminus of tropoelastin to domain 26, inclusive, bound MAGP-1 with a dissociation constant of 9.7 ± 2.0 nm, which decreased to 4.9 ± 1.0 nm following the removal of domain 26 (M155n), thus displaying only half the total capacity to bind MAGP-1. These results demonstrate that MAGP-1 is capable of cumulative binding to distinct regions on tropoelastin, with different apparent dissociation constants and different amounts of bound protein. [source] Essential oils and a novel polyacetylene from Eryngium yuccifolium Michaux. (Apiaceae),FLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2006Nahla Ayoub Abstract The essential oils of Eryngium yuccifolium Michaux. (Apiaceae) were isolated from the leaves, stalks and roots by hydrodistillation. Analysis of the oils by GC and GC,MS revealed that the leaves oil contained 49 compounds, of which germacrene D (18.3%), terpinolene (17.8%), bicyclogermacrene (8.8%), , -pinene (7.6%), ß-caryophyllene (6.2%) and falcarinol (9.6%) were found to be the major constituents. In addition, 40 compounds were identified from the stalk oil, among which, germacrene D (38.4%), , -amorphene (12.2%), bicyclogermacrene (10.1%), bicyclosesquiphellandrene (3.4%) and falcarinol (3.2%) were the major components. The roots oil was found to contain 25 compounds, of which, terpinolene (25.8%), trans - , -bergamotene (18.6%) and the benzaldehyde 2,3,6-trimethylbenzaldehyde (13.9%), were the major constituents. Yuccifolol (nonadeca-1,11-diene-4,6,8-triyne-3,10-diol), a novel polyacetylene, was isolated and identified from the hexane:ether extract of the aerial parts, together with the known polyacetylenes, falcarinone [heptadeca-1,9-(Z)-dien-4,6-diyn-3-one], falcarinol (heptadeca-1,9-dien-4,6-diyn-3-ol) and heptadeca-1,8-diene-4,6-diyne-3,9-diol. The chemical structures of these constituents were established by NMR (DEPT, COSY, HMQC and HMBC) as well as HRESI,MS analysis. Copyright © 2006 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||