Cv.

Distribution by Scientific Domains

Kinds of Cv.

  • l. cv.


  • Selected Abstracts


    Predictors for Maintenance of Sinus Rhythm after Cardioversion in Patients with Nonvalvular Atrial Fibrillation

    ECHOCARDIOGRAPHY, Issue 5 2002
    Ökçün M.D.
    Recurrence of atrial fibrillation (AF) after cardioversion (CV) to sinus rhythm (SR) is determined by various clinical and echocardiographic parameters. Transesophageal echocardiographic (TEE) parameters have been the focus of clinicians' interests for restoring and maintaining SR. This study determined the clinical, transthoracic, and TEE parameters that predict maintenance of SR in patients with nonvalvular AF after CV. We enrolled 173 patients with nonvalvular AF in the study. TEE could not be performed in 26 patients prior to CV. Twenty-five patients had spontaneously CV prior to TEE. Six patients were excluded because of left atrial (LA) thrombus assessed by TEE. CV was unsuccessful in 6 patients. The remaining 110 consecutive patients (56 men, 54 women, mean age 69 ± 9 years), who had been successfully cardioverted to SR, were prospectively included in the study. Fifty-seven (52%) patients were still in SR 6 months after CV. Age, gender, the configuration of the fibrillation wave on the electrocardiogram, pulmonary venous diastolic flow, and the presence of diabetes, hypertension, coronary artery disease, mitral annulus calcification, and mitral valve prolapse (MVP) did not predict recurrence. Duration of AF, presence of chronic obstructive pulmonary disease (COPD), LA diameter, left ventricular ejection fraction (EF), left atrial appendage peak flow (LAAPF), LAA ejection fraction (LAAEF), pulmonary venous systolic flow (PVSF), and the presence of LA spontaneous echo contrast (LASEC) predicted recurrence of AF 6 months after CV. In multivariate analysis, LAAEF < 30% was found to be the only independent variable (P < 0.0012) predicting recurrence at 6 months after CV in patients with nonvalvular AF. LAAEF more than 30% had a sensitivity of 75% and a specificity of 88% in predicting maintenance of SR 6 months after CV in patients with nonvalvular AF. In conclusion, TEE variables often used to determine thromboembolic risk also might be used to predict the outcome of CV. [source]


    Strategic Use of Corporate Venturing

    ENTREPRENEURSHIP THEORY AND PRACTICE, Issue 2 2007
    Jeffrey G. Covin
    Corporate venturing (CV) is said to be most productive as a path to superior corporate performance when practiced in a strategic manner. Unfortunately, considerable ambiguity exists concerning what it means in an organizational practice sense to strategically pursue CV. The result is a failure of many companies to fully leverage CV for strategic purposes. Based on a review of the CV literature and findings from a field study of 15 Swedish, U.K., and U.S. corporations, this article describes several models that depict the ways in which CV and business strategy coexist as organizational phenomena. Empirically derived propositions are offered to suggest how some companies are strategically engaged in their CV efforts. [source]


    A Comparison of CV-Catheters (CV) Grafts (GR) and Fistulae (FI) in Quotidian Hemodialysis

    HEMODIALYSIS INTERNATIONAL, Issue 1 2003
    C Kjellstrand
    We studied longevity and complications from CV, GR, and FI in 23 patients on quotidian hemodialysis. There were a total of 409 patient months, mean 18,10 months observation and a total of 9209 dialyses. There were 14 FI, 5 GR and 4 CV. 1, 1 and 2 replacements were necessary during a total observation time of 254, 105 and 50 patient months, respectively. For fistulae there were 0.02 replacements/year vs. 0.30 for GR and 0.41 for CV. P = 0.042 FI vs. other. The cumulative survival at 15 months was 100% for FI, 80% for GR and 20% for CV. P = 0.041. The cumulative survival at 3 years were 80% for fistulae and grafts, no CV lasted beyond 15 months. P = 0.013. There were 27 events requiring hospitalization or outpatient intervention. FI: 0.42/patient year, GR 1.22/patient year and CV 1.36/patient year. P = 0.080, FI vs. Other. Patients reported more problems between dialysis for FI, 3.2% of the days and least on GR (0.2%), CV (0.4%). P < 0.0001. Of the problems 85% were pain and redness. To the contrary there were more problems during dialysis with CV, 9.1% vs. FI 2.7%, and GR 0.9%. P < 0.0001. The complications and survival data are similar to those reported by others for quotidian hemodialysis and no different from reports on conventional 3 times per week dialyses. Conclusion: Daily hemodialysis does not adversely affect the different types of blood access. The survival and intervention need of accesses is best for fistulae, worst for CV, but GR, when functioning, have fewer problems between and during dialyses. [source]


    The heart of the South American rattlesnake, Crotalus durissus

    JOURNAL OF MORPHOLOGY, Issue 9 2010
    Bjarke Jensen
    Abstract Most anatomical and physiological studies of the sauropsid heart have focused on species with extraordinary physiologies, and detailed anatomical descriptions of hearts from sauropsids with more common physiologies are therefore warranted. Here, we present a comprehensive study of the cardiac anatomy of the South American rattlesnake (Crotalus durissus). The cardiovascular physiology of this species has been investigated in a number of studies, whereas only a few cursory studies exist on the cardiac anatomy of viperid snakes. The heart of C. durissus is typically squamate in many regards. Both atria are thin-walled sacs, and the right atrium is the most voluminous. The single ventricle contains three major septa; the vertical septum, the muscular ridge (MR), and the bulbuslamelle. These partially divide the ventricle into three chambers; the systemic and left-sided cavum arteriosum (CA), the pulmonary and right-sided cavum pulmonale, and the medial cavum venosum (CV). The MR is the most developed septum, and several additional and minor septa are found within the CA and CV. An extraordinary thin cortical layer encloses the ventricle, and it is irrigated by a remarkably rich arborization of coronary arteries. Previous studies show high degrees of blood flow separation in the Crotalus heart, and this can only be explained by the coordinated actions of the septa and the prominent atrioventricular valves. J. Morphol. 271:1066-1077, 2010. © 2010 Wiley-Liss, Inc. [source]


    Reactions of 1,2,5-thiadiazole 1,1-dioxide derivatives with nitrogenated nucleophiles.

    JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 4 2003
    1-dioxide, 4-diphenyl-, 5-thiadiazole , Addition of amines, Part , amides to
    Abstract The addition reactions of some amides and aromatic amines to a CN double bond of 3,4-diphenyl-1,2,5-thiadiazole 1,1-dioxide (1) were studied in aprotic solvent solutions [N,N -dimethylformamide (DMF) and acetonitrile (MeCN)]. Equilibrium constants for the reactions of 1 with acetamide, 2-fluoroacetamide, butyramide, benzamide, aniline and 3-aminopyridine were measured using a previously reported cyclic voltammetric (CV) method. Aliphatic amines gave unstable solutions, probably owing to reactions of anionic species derived from 1. Other N nucleophiles tested (formamide, succinimide, thioacetamide and cyanamide) yielded different products that have not yet been characterized. DMF, N,N -dimethylacetamide (DMA) and N -methylacetamide did not react. The addition thiadiazoline produced in the reaction of acetamide with 1 was characterized by IR and 1H and 13C RMN NMR spectroscopy as a prototype compound. For this system, the equilibrium constant could also be measured by a standard UV,VIS method and was found to be in agreement with the value obtained by CV. The reaction of 1 with urea produced a bicyclic product, identified as 3a,6a-diphenyltetrahydroimidazo[4,5- c]-1,2,5-thiadiazol-5-one 2,2-dioxide. Copyright © 2003 John Wiley & Sons, Ltd. [source]


    The utility of quantitative calf muscle near-infrared spectroscopy in the follow-up of acute deep vein thrombosis

    JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 4 2006
    T. YAMAKI
    Summary.,Background:,To investigate patterns of venous insufficiency and changes in calf muscle deoxygenated hemoglobin (HHb) levels after an acute deep vein thrombosis (DVT). Methods:,A total of 78 limbs with an acute DVT involving 156 anatomic segments were evaluated with duplex scanning and near-infrared spectroscopy (NIRS) at 1, 3, 6 and 12 months. Venous segments were examined whether they were occluded, partially recanalized, and totally recanalized, and the development of venous reflux was noted. The NIRS was used to measure calf muscle HHb levels. Calf venous blood filling index (HHbFI) was calculated on standing, then the calf venous ejection index (HHbEI), and the venous retention index (HHbRI) were obtained after exercise. Results:,The segments investigated were the common femoral vein (CFV; 38 segments), femoral vein (FV; 37), popliteal vein (POPV; 44), and calf veins (CV; 37). At 1 year, thrombi had fully resolved in 67% of the segments, 27% remained partially recanalized, 6% were occluded. The venous occlusion was predominant in the FV (24%) at 1 year. On the contrary, rapid recanalization was obtained in CV than proximal veins at each examination (P < 0.01). Venous reflux was predominant in POPV (55%), followed by FV (19%), and no reflux was found in CV. At 1 year, the HHbFI in POPV reflux patients was significantly higher than those with resolution (0.19 ± 0.14, 0.11 ± 0.05 ,m s, P = 0.009, respectively). Similarly, there was a significant difference in the HHbRI between the two groups (3.08 ± 1.91, 1.42 ± 1.56, P = 0.002, respectively). In patients with FV occlusion, the value of HHbRI was significantly higher than those with complete resolution (2.59 ± 1.50, 1.42 ± 1.56, P = 0.011, respectively). Conclusions:,The lower extremity venous segments show different proportions of occlusion, partial recanalization, and total recanalization. The CV shows more rapid recanalization than proximal veins. The NIRS-derived HHbFI and HHbRI could be promising parameters as the overall venous function in the follow-up of acute DVT. These findings might be very helpful for physician in detecting patients who require much longer follow-up studies. [source]


    Multilayer Thin Films by Layer-by-Layer Assembly of Hole- and Electron-Transport Polyelectrolytes: Optical and Electrochemical Properties

    MACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 20 2006
    Kyungsun Choi
    Abstract Summary: In this paper, we present the synthesis of a series of p-type and n-type semiconducting polyelectrolytes with triarylamine, oxadiazole, thiadiazole and triazine moieties. The synthesized polymeric hole and electron transport materials were examined optically and electrochemically using UV/Vis spectroscopy, PL spectroscopy and CV. Based on the optical and electrochemical data, each of the energy levels were calculated and all values suggested that they were promising hole- (p-type) or electron-transport (n-type) materials for devices. Moreover, the synthesized ionic polymers were suitable for LBL thin film deposition from dilute polymer solutions and the multilayers were fully characterized by UV/Vis, PL spectroscopy and CV. [source]


    Re: Phull H, Salkini M, Escobar C, Purves T, Comiter CV. 2006.

    NEUROUROLOGY AND URODYNAMICS, Issue 1 2007
    The role of angiotensin II in stress urinary incontinence: A rat model.
    [source]


    The Influence of Left Ventricle Diastolic Function on Natriuretic Peptides Levels in Patients with Atrial Fibrillation

    PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 6 2009
    DAWID BAKOWSKI M.D., Ph.D.
    Background:The diagnosis of the impaired left ventricle (LV) diastolic function during atrial fibrillation (AF) using traditional methods is very difficult. Natriuretic peptides seem to be useful for assessment of diastolic function in patients with AF. Aim:To evaluate the influence of LV diastolic dysfunction on natriuretic peptides concentrations and to assess the diagnostic value of atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) in patients with AF and impaired LV diastolic function. Methods:The study included 42 patients (23 males, 19 females), aged 58.6 ± 8.2 years with nonvalvular persistent AF with preserved LV systolic function who were converted into sinus rhythm by DC cardioversion (CV) and maintained sinus rhythm for at least 30 days. Echocardiography (ECG), ANP, and BNP level measurements were taken at baseline 24 hours before CV and 24 hours and 30 days after CV. On the 30th day following CV in patients with sinus rhythm, Doppler ECG was performed to assess LV diastolic function. Results:Thirty days after CV, normal LV diastolic function in 15 patients and impaired diastolic function in 27 patients was diagnosed: 20 with impaired LV relaxation and seven with impaired LV compliance. During AF and 24 hours, and 30 days after sinus rhythm restoration, significantly higher ANP and BNP levels were observed in patients with LV diastolic dysfunction as compared to the subgroup with normal LV diastolic function. The average values of ANP during AF in patients with normal and impaired diastolic function were 167.3 ± 70.1 pg/mL and 298.7 ± 83.6 pg/mL, respectively (P < 0.001), and the average values of BNP in the above mentioned subgroups were 49.5 ± 14.7 pg/mL and 145.6 ± 49.6 pg/mL respectively (P < 0.001). While comparing the diagnostic value of both natriuretic peptides it was noted that BNP was a more specific and sensitive marker of impaired LV diastolic function. ANP value >220.7 pg/mL measured during AF identified patients with impaired LV diastolic function with 85% sensitivity and 90% specificity. BNP value >74.7 pg/mL proved 95% sensitive and 100% specific in the diagnosing of such a group. Conclusions:The increase of ANP/BNP concentration in patients with AF results not only from the presence of AF, but also reflects the impaired LV diastolic function. Natriuretic peptides, especially BNP, may be useful in diagnosing LV diastolic dysfunction in patients with AF. [source]


    Reversal of Atrial Remodeling after Cardioversion of Persistent Atrial Fibrillation Measured with Magnetocardiography

    PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2009
    MIKA LEHTO M.D.
    Background: Atrial fibrillation (AF) causes electrical, functional, and structural changes in the atria. We examined electrophysiologic remodeling caused by AF and its reversal noninvasively by applying a new atrial signal analysis based on magnetocardiography (MCG). Methods: In 26 patients with persistent AF, MCG, signal-averaged electrocardiography (SAECG), and echocardiography were performed immediately after electrical cardioversion (CV), and repeated after 1 month in 15 patients who remained in sinus rhythm (SR). Twenty-four matched subjects without history of AF served as controls. P-wave duration (Pd) and dispersion (standard deviation of Pd values in individual channels) and root mean square amplitudes of the P wave over the last 40 ms portions (RMS40) were determined. Results: In MCG Pd was longer (122.8 ± 18.2 ms vs 101.5 ± 14.6 ms, P < 0.01) and RMS40 was higher (60.4 ± 28.2 vs 46.9 ± 19.1 fT) in AF patients immediately after CV as compared to the controls. In SAECG Pd dispersion was increased in AF patients. Mitral A-wave velocity and left atrial (LA) contraction were decreased and LA diameter was increased (all P < 0.01). After 1 month, Pd in MCG still remained longer and LA diameter greater (both P < 0.05), while RMS40 in MCG, Pd dispersion in SAECG, mitral A-wave velocity, and LA contraction were recovered. Conclusions: Magnetocardiographically detected atrial electrophysiologic alterations in persistent AF diminish rapidly although incompletely during maintained SR after CV. This might be related to the known early high and late lower, but still existent tendency to AF relapses. [source]


    Reverse Electrical Remodeling of the Atria Post Cardioversion in Patients Who Remain in Sinus Rhythm Assessed by Signal Averaging of the P-Wave

    PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 4 2007
    NAGIB CHALFOUN M.D.
    Objectives: This study was designed to determine whether the signal-averaged electrocardiogram of the P-wave (SAPW) is an independent predictor of recurrence of atrial fibrillation (AF) post cardioversion (CV), and to assess atrial remodeling using SAPW. Background: There are limited electrophysiologic data to predict the recurrence of AF post-CV. The electrical remodeling that occurs post-CV is poorly understood. Methods: Sixty-four patients with persistent AF undergoing CV were prospectively enrolled. SAPW parameters were measured the day of CV and repeated at 1 month. These SAPW parameters were compared to other baseline indices for the recurrence of AF. Results: Sixty patients (94%) had successful CV. At 1 month, 22 (37%) maintained sinus rhythm (SR). The SAPW total duration decreased significantly in those who remained in SR (159 ms ± 19 to 146 ms ± 17; P < 0.0001). Only the duration of AF (46 ± 50 days vs 147 ± 227 days, P = 0.03) and the presence of left ventricular hypertrophy (LVH, 12% vs 65%, P = 0.0006) were significantly associated with recurrence of AF. Atrial size strongly correlated with the SAPW duration in patients who remained in SR (R2= 0.67, P = 0.003) but not in those who returned to AF (R2= 0.11, P = 0.65). Conclusions: Atrial electrical reverse remodeling occurs in patients with AF who maintain SR post-CV. This remodeling is likely inversely related to the duration of AF and LVH. SAPW duration does not predict recurrence of AF post-CV. [source]


    Public Values for River Restoration Options on the Middle Rio Grande

    RESTORATION ECOLOGY, Issue 6 2009
    Matthew A. Weber
    Abstract River restoration is a widespread phenomenon. This reflects strong public values for conservation, though missing are studies explicitly justifying restoration expenditures. Public restoration benefits are not well quantified, nor are public preferences among diverse activities falling into the broad category "restoration." Our study estimates public values for restoration on the Middle Rio Grande, New Mexico. Stakeholder meetings and public focus groups guided development of a restoration survey mailed to Albuquerque area households. Four restoration categories were defined: fish and wildlife; vegetation density; tree type; and natural river processes. Survey responses supplied data for both choice experiment (CE) and contingent valuation (CV) analyses, two established environmental economics techniques for quantifying public benefits of conservation policies. Full restoration benefits are estimated at over $150 per household per year via the CE and at nearly $50 per household per year via CV. The CE allows value disaggregation among different restoration categories. The most highly valued category was tree type, meaning reestablishing native tree dominance for such species as Cottonwood (Populus deltoides) and eradicating non-native trees such as Saltcedar (Tamarix ramosissma). The high public values we have found for restoration offer economic justification for intensive riparian management, particularly native plant-based restoration in the Southwest. [source]


    The relationships between half-life (t1/2) and mean residence time (MRT) in the two-compartment open body model

    BIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 4 2004
    Eyal Sobol
    Abstract Rationale. In the one-compartment model following i.v. administration the mean residence time (MRT) of a drug is always greater than its half-life (t1/2). However, following i.v. administration, drug plasma concentration (C) versus time (t) is best described by a two-compartment model or a two exponential equation: C=Ae,,t+Be,,t, where A and B are concentration unit-coefficients and , and , are exponential coefficients. The relationships between t1/2 and MRT in the two-compartment model have not been explored and it is not clear whether in this model too MRT is always greater than t1/2. Methods. In the current paper new equations have been developed that describe the relationships between the terminal t1/2 (or t1/2,) and MRT in the two-compartment model following administration of i.v. bolus, i.v. infusion (zero order input) and oral administration (first order input). Results. A critical value (CV) equals to the quotient of (1,ln2) and (1,,/,) (CV=(1,ln2)/(1,,/,)=0.307/(1,,/,)) has been derived and was compared with the fraction (f1) of drug elimination or AUC (AUC-area under C vs t curve) associated with the first exponential term of the two-compartment equation (f1=A/,/AUC). Following i.v. bolus, CV ranges between a minimal value of 0.307 (1,ln2) and infinity. As long as f1t1/2 and vice versa, and when f1=CV, then MRT=t1/2. Following i.v. infusion and oral administration the denominator of the CV equation does not change but its numerator increases to (0.307+,T/2) (T-infusion duration) and (0.307+,/ka) (ka-absorption rate constant), respectively. Examples of various drugs are provided. Conclusions. For every drug that after i.v. bolus shows two-compartment disposition kinetics the following conclusions can be drawn (a) When f1<0.307, then f1t1/2. (b) When ,/,>ln2, then CV>1>f1 and thus, MRT>t1/2. (c) When ln2>,/,>(ln4,1), then 1>CV>0.5 and thus, in order for t1/2>MRT, f1 has to be greater than its complementary fraction f2 (f1>f2). (d) When ,/,<(ln4,1), it is possible that t1/2>MRT even when f2>f1, as long as f1>CV. (e) As , gets closer to ,, CV approaches its maximal value (infinity) and therefore, the chances of MRT>t1/2 are growing. (f) As , becomes smaller compared with ,, ,/, approaches zero, the denominator approaches unity and consequently, CV gets its minimal value and thus, the chances of t1/2>MRT are growing. (g) Following zero and first order input MRT increases compared with i.v. bolus and so does CV and thus, the chances of MRT>t1/2 are growing. Copyright © 2004 John Wiley & Sons, Ltd. [source]


    Premières observations de Verticillium dahliae sur olivier en Tunisie

    EPPO BULLETIN, Issue 1 2006
    M. A. Triki
    Au cours des prospections effectuées dans les oliveraies de la délégation de Mahres (région de Sfax) située au centre-est de la Tunisie, 12 cas de dépérissement d'oliviers âgés, du cv. ,Chemlali' ont été observés dans deux parcelles voisines. Dans ces deux vergers, les oliviers malades sont répartis en foyers. Les investigations au champ et au laboratoire ont permis de mettre en évidence la présence du champignon Verticillium dahliae, qui est ainsi signalé pour la première fois en Tunisie sur olivier. [source]


    Protein disulfide isomerase family proteins involved in soybean protein biogenesis

    FEBS JOURNAL, Issue 3 2007
    Hiroyuki Wadahama
    Protein disulfide isomerase family proteins are known to play important roles in the folding of nascent polypeptides and the formation of disulfide bonds in the endoplasmic reticulum. In this study, we cloned two similar protein disulfide isomerase family genes from soybean leaf (Glycine max L. Merrill cv. Jack) mRNA by RT-PCR using forward and reverse primers designed from the expressed sequence tag clone sequences. The cDNA encodes a protein of either 364 or 362 amino acids, named GmPDIS-1 or GmPDIS-2, respectively. The nucleotide and amino acid sequence identities of GmPDIS-1 and GmPDIS-2 were 68% and 74%, respectively. Both proteins lack the C-terminal, endoplasmic reticulum-retrieval signal, KDEL. Recombinant proteins of both GmPDIS-1 and GmPDIS-2 were expressed in Escherichia coli as soluble folded proteins that showed both an oxidative refolding activity of denatured ribonuclease A and a chaperone activity. Their domain structures were identified as containing two thioredoxin-like domains, a and a,, and an ERp29c domain by peptide mapping with either trypsin or V8 protease. In cotyledon cells, both proteins were shown to distribute to the endoplasmic reticulum and protein storage vacuoles by confocal microscopy. Data from coimmunoprecipitation and crosslinking experiments suggested that GmPDIS-1 associates with proglycinin, a precursor of the seed storage protein glycinin, in the cotyledon. Levels of GmPDIS-1, but not of GmPDIS-2, were increased in cotyledons, where glycinin accumulates during seed development. GmPDIS-1, but not GmPDIS-2, was induced under endoplasmic reticulum-stress conditions. [source]


    Post-harvest storage effect on quantity and quality of rose-scented geranium (Pelargonium sp. cv. ,Bourbon') oil in Uttaranchal

    FLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2005
    P. Ram
    Abstract Drying and storage of herbage for 5 days prior to distillation significantly reduced the essential oil recovery as well as oil quality. The study suggested that the geranium green biomass should be distilled afresh for better oil yield and quality in the conditions of Uttaranchal. Copyright © 2005 John Wiley & Sons, Ltd. [source]


    Leaf and peel volatile compounds of an interspecific citrus somatic hybrid [Citrus aurantifolia (Christm.) Swing. + Citrus paradisi Macfayden]

    FLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2002
    Anne-Laure Gancel
    Abstract The volatile compounds from leaves and peels of an interspecific citrus somatic hybrid, Citrus aurantifolia (Christm.) Swing. + Citrus paradisi Macfayden, obtained by fusion of protoplasts from lime, Citrus aurantifolia (cv. Mexican Lime) and grapefruit, Citrus paradisi (cv. Star Ruby), were extracted by pentane : ether (1 : 1) from liquid nitrogen ball-milled leaves and flavedo and examined by GC,MS in comparison to those of its parents. The hybrid quantitatively retained the ability of the lime parent to synthesize in its leaves the major monoterpene aldehydes (neral, geranial) the monoterpene alcohols (nerol, geraniol), and their acetates, and also the capacity of the grapefruit parent to produce a sesquiterpene aldehyde (,-sinensal) in its leaves and nootkatone in its peel. Conversely, synthesis of most sesquiterpene hydrocarbons and long chain aliphatic aldehydes, which are present in the lime parent leaves and peel, was strongly inhibited in the hybrid, as in the grapefruit parent. In comparison to its parents, the hybrid overproduced citronellal in its leaves and ,-sinensal and ,-sinensal in its peel. Based on these results, the future prospects for a better understanding of the inheritance mechanisms with regards to aroma biosynthesis in citrus leaves and peels are discussed. Copyright © 2002 John Wiley & Sons, Ltd. [source]


    Distribution of degradative enzymatic activities in the mesocarp of two melon groups

    INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 5 2010
    Marco Chisari
    Summary The differences in polyphenol oxidase, peroxidase, pectin methylesterase and polygalacturonase activities as well as the main physical and chemical attributes of nine different slice portions (from the inner to the outer end and from the blossom to the stem end) of two groups of melon (Cucumis melo var. cantalupensis,Galia' cv. and inodorus,Piel de sapo' cv.) at commercial maturity were studied. Moving from the inner to the outer end of the pulp, physico-chemical properties, such as pH, total soluble solids and phenolics increased whereas titratable acidity, firmness and Chroma decreased in both types, reflecting different degrees of maturity within the same fruit. As for physico-chemical attributes, the enzymatic activities responsible for browning and softening phenomena showed an increasing trend moving from the inner to the outer end of mesocarp in both cv., except for polygalacturonase in cantalupensis type. [source]


    Compensative Effects of Chemical Regulation with Uniconazole on Physiological Damages Caused by Water Deficiency during the Grain Filling Stage of Wheat

    JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 1 2008
    L. Duan
    Abstract Chemical regulation using plant growth regulators has proved to be potentially beneficial in water-saving agriculture. This experiment was conducted with winter wheat (Triticum aestivum L. cv. ,Jingdong 6') to study the effect of chemical regulation on alleviation of water deficit stress during the grain filling stage. Uniconazole, a plant growth regulator, was foliar sprayed at 85 % (adequate irrigation) and 60 % (deficit irrigation) field capacity. Results showed that the distribution of 3H-H2O in roots and flag leaf, characteristics of vascular bundle in primary roots and internode below spike, roots activity, transpiration rate and stomatal conductance of flag leaf were negatively affected by deficit irrigation after flowering. Foliar spraying at the early jointing stage with 13.5 gha,1 uniconazole was able to relieve and compensate for the harmful effects of deficit irrigation. Both the area of vascular bundle in primary roots and internode below the ear were increased by uniconazole, while root viability and their ability to absorb and transport water were increased. In the flag leaf, stomatal conductance was reduced to maintain the transpiration rate and water use efficiency (WUE) measured for a single wheat plant was higher. Uniconazole increased WUE by 25.0 % under adequate and 22 % under deficit irrigations. Under adequate irrigations, the 14C-assimilates export rate from flag leaf in 12 h (E12h) was increased by 65 % and 36 % in early and late filling stages, while under deficit irrigations, the E12h of uniconazole-treated plants exceeded that of control plants by 5 % and 34 % respectively. Physiological damages caused by water deficiency during the grain filling stage of wheat was alleviated by foliar spraying with uniconazole. [source]


    Cadmium Enhances Generation of Hydrogen Peroxide and Amplifies Activities of Catalase, Peroxidases and Superoxide Dismutase in Maize

    JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 1 2008
    P. Kumar
    Abstract Maize (Zea mays L. cv. 777) plants grown in hydroponic culture were treated with 50 ,m CdSO4. Growth and metabolic parameters indicative of oxidative stress and antioxidant responses were studied in leaves of plants treated with Cd. Apart from increasing lipid peroxidation and H2O2 accumulation, supply of Cd suppressed growth, fresh and dry mass of plants and decreased the concentrations of chloroplastic pigments. The activities of catalase (CAT; EC 1.11.1.6), peroxidase (POD; EC 1.11.1.7), ascorbate peroxidase (APX; EC 1.11.1.11) and superoxide dismutase (SOD; EC 1.15.1.1) were increased in plants supplied 50 ,m Cd. Localization of activities of isoforms of these enzymes (POD, APX and SOD) on native gels also revealed increase in the intensities of pre-existing bands. Stimulated activities of CAT, POD, APX and SOD in maize plants supplied excess Cd do not appear to have relieved plants from excessive generation of reactive oxygen species (ROS). It is, therefore, concluded that supply of 50 ,m Cd induces oxidative stress by increasing production of ROS despite increased antioxidant protection in maize plants. [source]


    Mass Production of Intergeneric Chromosomal Translocations through Pollen Irradiation of Triticum durum-Haynaldia villosa Amphiploid

    JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 11 2007
    Tong-De Bie
    Abstract Haynaldia villosa possesses a lot of important agronomic traits and has been a powerful gene resource for wheat improvement. However, only several wheat,H. villosa translocation lines have been reported so far. In this study, we attempted to develop an efficient method for inducing wheat,H. villosa chromosomal translocations. Triticum durum-Haynaldia villosa amphiploid pollen treated with 1 200 rad 60Co-,-rays was pollinated to Triticum aestivum cv. ,Chinese Spring'. Ninety-eight intergeneric translocated chromosomes between T. durum and H. villosa were detected by genomic in situ hybridization in 44 of 61 M1 plants, indicating a translocation occurrence frequency of 72.1%; much higher than ever reported. There were 26, 62 and 10 translocated chromosomes involving whole arm translocations, terminal translocations, and intercarlary translocations, respectively. Of the total 108 breakage-fusion events, 79 involved interstitial regions and 29 involved centric regions. The ratio of small segment terminal translocations (W·W-V) was much higher than that of large segment terminal translocations (W-V·V). All of the M1 plants were self-sterile, and their backcross progeny was all obtained with ,Chinese Spring' as pollen donors. Transmission analysis showed that most of the translocations were transmittable. This study provides a new strategy for rapid mass production of wheat-alien chromosomal translocations, especially terminal translocations that will be more significant for wheat improvement. [source]


    Introgression of Resistance to Powdery Mildew Conferred by Chromosome 2R by Crossing Wheat Nullisomic 2D with Rye

    JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 7 2006
    Diao-Guo An
    Abstract Using the nullisomic back-cross procedure, four wheat-rye chromosome substitution 2R (2D) lines with different agronomic performance, designated WR02-145-1, WR01-145-2, WR02-145-3, and WR02-145-4, were produced from a cross between 2D nullisomic wheat (Triticum aestivum L. cv. "Xiaoyan 6") and rye (Secale cereale L. cv. "German White"). The chromosomal constitution of 2n=42=21 in WR02-145 lines was confirmed by cytological and molecular cytogenetic methods. Using genomic in situ hybridization on root tip chromosome preparations, a pair of intact rye chromosomes was detected in the WR02-145 lines. PCR using chromosome-specific primers confirmed the presence of 2R chromosomes of rye in these wheat-rye lines, indicating that WR02-145 lines are disomic chromosome substitution lines 2R(2D). The WR02-145 lines are resistant to the powdery mildew (Erysiphe graminis DC. f. sp. tritici E. Marchal) isolates prevalent in northern China and may possess gene(s) for resistance to powdery mildew, which differ from the previously identified Pm7 gene located on chromosome 2RL. The newly developed "Xiaoyan 6"- "German White" 2R (2D) chromosome substitution lines are genetically stable, show desirable agronomic traits, and are expected to be useful in wheat improvement. (Managing editor: Li-Hui Zhao) [source]


    Use of a Mini-Dome Bioassay and Grafting to Study Resistance of Chickpea to Ascochyta Blight

    JOURNAL OF PHYTOPATHOLOGY, Issue 10 2005
    W. Chen
    Abstract A mini-dome bioassay was developed to study pathogenicity of Ascochyta rabiei and relative resistance of chickpea (Cicer arietanium). It was determined that the best condition for assaying pathogenicity of A. rabiei was to use 2 × 105 spores/ml as inoculum and to maintain a leaf wetness period of 24 h under mini-domes at a temperature between 16 and 22°C. This mini-dome pathogenicity assay was used to determine relative resistance of six chickpea cultivars (cvs) to isolates of two pathotypes of A. rabiei. Grafting was employed to detect any translocated factors produced in the chickpea plant that mediate disease response, which could help elucidate possible resistance mechanisms to Ascochyta blight. The six chickpea cv. were grafted in all possible scion,rootstock combinations, and then inoculated with isolates of two pathotypes of A. rabiei using the mini-dome technique. Results showed that self-grafted-resistant plants remained resistant and self-grafted-susceptible plants stayed susceptible, indicating the grafting procedure did not alter host response to infection by A. rabiei. Susceptible scions always exhibited high and similar levels of disease severity regardless of rootstock genotypes, and resistant scions always showed low and similar levels of disease severity when they were grafted onto any of the six rootstock genotypes. Orthogonal contrasts showed that scion genotypes determined disease phenotype, and that rootstock genotypes had no contribution to disease phenotype of the scions. The pathogenicity assay did not detect any translocated disease-mediating agents responsible for susceptibility or resistance in chickpea. Disease phenotypes of Ascochyta blight of chickpea were conditioned locally by scion genotypes. [source]


    Utricularia (Lentibulariaceae) , a New Host Plant Genus of Powdery Mildew (Sphaerotheca sp.)

    JOURNAL OF PHYTOPATHOLOGY, Issue 3-4 2001
    Lebeda
    Symptoms of powdery mildew infections were recorded on a group of 15 Utricularia species cultivated in a glasshouse. A white superficial mycelium formed rings around the peduncles and also occurred on both sides of the leaves of several species. The microscopic examination proved that the fungus belonged to the powdery mildews , Erysiphales, only the anamorph was observed. Its morphological characters are typical for powdery mildews from the tribe Cystotheceae. Conidia were able to cause infections on cotyledons of susceptible Cucumis sativus cv. Stela F1. Based on all observations, it is very probable that this fungus belongs to the genus Sphaerotheca. This is the first report of a powdery mildew on Utricularia spp. and the family Lentibulariaceae. Utricularia(Lentibulariaceae) , eine neue Wirtspflanzengattung des Echten Mehltaus (Sphaerothecasp.) Symptome von Infektionen mit dem Echten Mehltau wurden bei einer Gruppe von 15 in einem Gewächshaus gehaltenen Utricularia -Arten festgestellt. Ein weißes oberflächliches Myzel bildete Ringe um die Blütenstandsstiele und trat bei verschiedenen Arten auch auf beiden Seiten der Blätter auf. Mikroskopische Untersuchungen ergaben, daß es sich um einen Echten Mehltaupilz (Erysiphales) handelte; ausschließlich die Anamorph wurde beobachtet. Die morphologischen Merkmale sind typisch für Echte Mehltaupilze vom Stamm Cystotheceae. Die Konidien konnten auch Infektionen auf den Keimblättern anfälliger Pflanzen von Cucumis sativus cv. Stela F1 auslösen. Auf der Grundlage aller Beobachtungen erscheint es als sehr wahrscheinlich, daß dieser Pilz der Gattung Sphaerotheca angehört. Dies ist der erste Bericht über Echten Mehltau an Utricularia spp. und der Familie Lentibulariaceae. [source]


    Excess nickel,induced changes in antioxidative processes in maize leaves

    JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 6 2007
    Praveen Kumar
    Abstract Maize (Zea mays L. cv. 777) plants grown in hydroponic culture were treated with 100 µM NiSO4 (moderate nickel (Ni) excess). In addition to growth parameters, metabolic parameters representative of antioxidant responses in leaves were assessed 24 h and 3, 7, and 14 d after initiating the Ni treatment. Extent of oxidative damage was measured as accumulation of malondialdehyde and hydrogen peroxide in leaves 7 and 14 d after treatment initiation. Apart from increasing membrane-lipid peroxidation and H2O2 accumulation, excess supply of Ni suppressed plant growth and dry mass of shoots but increased dry mass of roots and decreased the concentrations of chloroplastic pigments. Excess supply of Ni, though inhibited the catalase (EC 1.11.1.6) activity, increased peroxidase (EC 1.11.1.7), ascorbate peroxidase (EC 1.11.1.11), and superoxide dismutase (EC 1.15.1.1) activities. Localization of isoforms of these enzymes (peroxidase, ascorbate peroxidase, and superoxide dismutase) on native gels also revealed increases in the intensities of pre-existing bands. Enhanced activities of peroxidase, ascorbate peroxidase, and superoxide dismutase, however, did not appear to be sufficient to ameliorate the effects of excessively generated reactive oxygen species due to excess supply of Ni. [source]


    Effects of wastewater irrigation on soil and cabbage-plant (brassica olerecea var. capitate cv. yalova-1) chemical properties

    JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 1 2007
    Fatih M. Kiziloglu
    Abstract The use of wastewater for irrigation is increasingly being considered as a technical solution to,minimize soil degradation and to restore nutrient contents of soils. The aim of this study is to increase fertility and minimize degradation of soils irrigated with wastewater exposed to different purification treatments. A field experiment was conducted to investigate the effects of control and irrigation with wastewater, which had undergone different purification treatments, on macro- and micronutrient distribution within the soil profile and nutrient contents of cabbage (Brassica olerecea var. Capitate cv. Yalova-1) in Erzurum, Turkey. Wastewater irrigation and preliminary treatment,wastewater irrigation significantly affected soil chemical properties especially at 0,30,cm soil depth and plant nutrient contents after one year. Application of wastewater increased soil salinity, organic matter, exchangeable Na, K, Ca, Mg, plant-available P, and micro-elements and decreased soil pH. Wastewater increased also yield and N, P, K, Fe, Mn, Zn, Cu, B, and Mo contents of cabbage plants. Undesirable side effects were not observed in plant heavy-metal contents, due to salinity and toxic concentrations of metals from the application of wastewater to soil. [source]


    Compositional nutrient diagnosis and main nutrient interactions in yellow pepper grown on desert calcareous soils

    JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 4 2004
    José Luis García-Hernández
    Abstract Mineral-nutrient stress is one of the main factors limiting crop production, especially in arid lands. The mineral requirement of a crop is difficult to determine, and the interpretation of foliar chemistry composition is not easy. This study was conducted to compute the minimum yield target for fresh fruit of yellow pepper (Capsicum annuum L.) and the corresponding Compositional Nutrient Diagnosis (CND) as well as to identify significant nutrient interactions of this crop in desert calcareous soils. Preliminary CND norms were developed using a cumulative variance-ratio function and the chi-square distribution function. From a small database, we computed means and standard deviations of row-centered log ratios, VX, of five nutrients (N, P, K, Ca, and Mg) and a filling value, R, which comprises all nutrients not chemically analyzed and quantified them in 54 foliar samples of the popular yellow pepper cv. ,Santa Fé'. This cultivar is widely grown in northwest Mexico under arid conditions. These norms are associated to fresh fruit yields higher than 15.04 t ha,1. Principal-component analyses, performed using estimated CND nutrient indexes, allowed us to identify four interactions: negative P-Ca, P-Mg, and N-K, and positive Ca-Mg. Pepper plants growing on calcareous soils tend to take up more Ca and Mg than considered as optimum in other soil conditions. [source]


    Genotype x environment interaction in the uptake of Cs and Sr from soils by plants

    JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 1 2004
    Alexei Melnitchouck
    Abstract The soil-plant transfer factors for Cs and Sr were analyzed in relationship to soil properties, crops, and varieties of crops. Two crops and two varieties of each crop: lettuce (Lactuca sativa L.), cv. Salad Bowl Green and cv. Lobjoits Green Cos, and radish (Raphanus sativus L.), cv. French Breakfast 3 and cv. Scarlet Globe, were grown on five different soils amended with Cs and Sr to give concentrations of 1 mg kg,1 and 50,mg,kg,1 of each element. Soil-plant transfer coefficients ranged between 0.12,19.10 (Cs) and 1.48,146.10 (Sr) for lettuce and 0.09,13.24 (Cs) and 2.99,93.00 (Sr) for radish. Uptake of Cs and Sr by plants depended on both plant and soil properties. There were significant (P , 0.05) differences between soil-plant transfer factors for each plant type at the two soil concentrations. At each soil concentration about 60,% of the variance in the uptake of the Cs and Sr was due to soil properties. For a given concentration of Cs or Sr in soil, the most important factor effecting soil-plant transfer of these elements was the soil properties rather than the crops or varieties of crops. Therefore, for the varieties considered here, soil-plant transfer of Cs and Sr would be best regulated through the management of soil properties. At each concentration of Cs and Sr, the main soil properties effecting the uptake of Cs and Sr by lettuce and radish were the concentrations of K and Ca, pH and CEC. Together with the concentrations of contaminants in soils, they explained about 80,% of total data variance, and were the best predictors for soil-plant transfer. The different varieties of lettuce and radish gave different responses in soil-plant transfer of Cs and Sr in different soil conditions, i.e. genotype x environment interaction caused about 30,% of the variability in the uptake of Cs and Sr by plants. This means that a plant variety with a low soil-plant transfer of Cs and Sr in one soil could have an increased soil-plant transfer factor in other soils. The broad implications of this work are that in contaminated agricultural lands still used for plant growing, contaminant-excluding crop varieties may not be a reliable method for decreasing contaminant transfer to foodstuffs. Modification of soil properties would be a more reliable technique. This is particularly relevant to agricultural soils in the former USSR still affected by fallout from the Chernobyl disaster. Wechselwirkungen Genotyp x Umwelt im Hinblick auf die Aufnahme von Cs und Sr aus Böden durch Pflanzen Die Transferfaktoren von Cs und Sr vom Boden zur Pflanze wurden in Zusammenhang mit den Bodeneigenschaften, der Fruchtart und der Sorte untersucht. Zwei Fruchtarten mit je zwei Sorten: Salat (Lactua sativa L.) cv. Salad Bowl Green und cv. Lobjoits Green Cos, und Rettich (Raphanus sativus L.) cv. French Breakfast 3 und cv. Scarlet Globe, wurden in fünf verschiedenen Böden, die mit Cs und Sr in Konzentrationen von je 1 mg kg,1 und 50 mg kg,1 angereichert wurden, untersucht. Die Boden-Pflanze-Transferkoeffizienten variierten für Salat von 0,12,19,10 (Cs) und 1,48,146,1 (Sr) und für Rettich von 0,09,13,24 (Cs) und 2,99,93,00 (Sr). Die Aufnahme von Cs und Sr durch Pflanzen hängt sowohl von der Pflanze als auch von den Bodeneigenschaften ab. Es gab signifikante (P , 0,05) Unterschiede zwischen den Boden-Pflanze-Transferfaktoren für jede Pflanzensorte bei beiden Konzentrationen im Boden. Bei jeder Konzentration im Boden wurde die Varianz für die Aufnahme von Cs und Sr zu ca. 60,% von den Bodeneigenschaften bestimmt. Für jede vorgegebene Konzentration von Cs oder Sr im Boden wurde der Boden-Pflanze-Transfer mehr durch die Bodeneigenschaften beeinflusst als durch die Fruchtart oder Sorte. Daher ist der Transfer von Cs und Sr für die hier untersuchten Sorten am besten über eine Beeinflussung der Bodeneigenschaften steuerbar. Die Aufnahme in Rettich und Salat wurde für alle untersuchten Cs- und Sr-Konzentrationen am stärksten durch die K- und Ca-Konzentrationen, den pH-Wert und die KAK der jeweiligen Böden beeinflusst. Die Konzentrationen der Schadstoffe in Böden und die beschriebenen Bodeneigenschaften erklärten ca. 80,% die Gesamtdatenvarianz und sind die besten Voranzeiger für den Boden-Pflanze-Transfer. Die verschiedenen Salat- und Rettichsorten reagierten im Transport von Cs und Sr vom Boden zur Pflanze unterschiedlich auf die verschiedenen Bodeneigenschaften. So erklärte z.,B. die Wechselwirkung Genotyp x Umweltbedingungen ca. 30,% der Variabilität der Pflanzenaufnahme von Cs und Sr. Das bedeutet, dass eine Sorte, die auf einem Boden einen geringen Boden-Pflanze-Transfer von Cs und Sr aufweist, auf einem anderen Boden einen höheren Boden-Pflanze-Transfer aufweisen kann. Die wichtigste Erkenntnis dieser Untersuchung besteht darin, dass die Veränderung der Bodeneigenschaften im Vergleich zum Einsatz von Sorten mit einer geringen Cs- und Sr-Akkumulationsrate auf kontaminierten landwirtschaftlichen Standorten eine aussichtsreichere Methode sein könnte, um die Aufnahme von Cs und Sr in Nahrungsmittel zu minimieren. Diese Aussage ist besonders für landwirtschaftliche Flächen in der früheren UdSSR relevant, die durch die Katastrophe von Chernobyl kontaminiert wurden. [source]


    Influence of delayed cooling on storability and postharvest quality of European plums

    JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 6 2009
    Marcos Guerra
    Abstract BACKGROUND: Delayed cooling has been tested to delay the development of internal breakdown (IB) in other stone fruits, but the influence of delayed cooling on IB has not been studied to date in European plums. A controlled delayed treatment of 48 h at 20 °C was applied in order to study the storability and postharvest quality of European plum (Prunus domestica L.) cv. ,Green Gage'. RESULTS: Market life of ,Green Gage' plums after shelf life was 10 days shorter in delayed fruits than in control fruits at earlier harvest dates. Sensory attributes affected by delayed cooling treatment at harvest were astringency and aroma. Prompt cooling was essential to lower the rate of physiological deterioration of plums, helping to maintain fruit quality and prolong market life. CONCLUSION: Delayed cooling increased IB symptoms in ,Green Gage' plums, so, when storability is needed, rapid cooling of fruits is necessary in order to extend their market life. Delayed cooling modified the total soluble solids/titratable acidity (TSS/TA) ratio and the sensory properties aroma and astringency at harvest, so it is desirable to deliver fruits directly to market in order to improve TSS/TA, the instrumental property best correlated with sensory characteristics. Copyright © 2009 Society of Chemical Industry [source]


    Characterization of a novel Toll/interleukin-1 receptor (TIR)-TIR gene differentially expressed in common bean (Phaseolus vulgaris cv. Othello) undergoing a defence response to the geminivirus Bean dwarf mosaic virus

    MOLECULAR PLANT PATHOLOGY, Issue 2 2007
    YOUNG-SU SEO
    SUMMARY Common bean (Phaseolus vulgaris L.) cultivar (cv.) Othello develops a hypersensitive response-associated vascular resistance to infection by Bean dwarf mosaic virus (BDMV), a single-stranded DNA virus (genus Begomovirus, family Geminiviridae). A PCR-based cDNA subtraction approach was used to identify genes involved in this resistance response. Eighteen clones, potentially involved with BDMV resistance, were identified based upon being up-regulated in BDMV-infected tissues and/or having sequence similarity with known resistance-associated genes. Analysis of these clones revealed potential genes involved in pathogen defence, including pathogenesis-related protein genes and resistance gene analogues (RGAs). Further characterization of one RGA, F1-10, revealed that it encodes a predicted protein with a double Toll/interleukin-1 receptor (TIR) motif. Full-length (F1-10) and spliced (F1-10sp) forms of the RGA were strongly up-regulated in BDMV-infected cv. Othello hypocotyl tissues by 4 days post-inoculation, but not in equivalent mock-inoculated tissues. In agroinfiltration experiments, F1-10, but not F1-10sp, mediated resistance to BDMV in the susceptible common bean cv. Topcrop. By contrast, transgenic Nicotiana benthamiana lines expressing F1-10 or F1-10sp were not resistant to BDMV. Interestingly, when these transgenic lines were inoculated with the potyvirus Bean yellow mosaic virus, some F1-10 lines showed a more severe symptom phenotype compared with non-transgenic control plants. Based on these findings, F1-10 was named: Phaseolus vulgaris VIRUS response TIR-TIR GENE 1 (PvVTT1). [source]