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PubMed1999

Bioconcentration of polycyclic aromatic hydrocarbons in vegetables grown in an industrial area.

The polycyclic aromatic hydrocarbon (PAH) content was determined in the inner tissue of various vegetable species and their growing environment (soil and atmosphere) in the greater industrial area of Thessaloniki, northern Greece. The lower molecular weight compounds dominated in both vegetable leaves and roots. Statistical analysis of variance showed that species and season are the factors that significantly affect PAH concentrations in inner vegetable tissue and soil, respectively. Principal component analysis indicated that the mixture of PAHs in inner vegetable tissue was very similar to that in air vapour thus suggesting gaseous deposition as the principal pathway for the accumulation of PAHs. Soil-to-vegetation and air-to-vegetation bioconcentration factors were calculated and their relationships with PAHs' physicochemical properties were investigated. Solubility and the octanol-water partition coefficient, as well as vapour pressure and the octanol-air partition coefficient were proved to be good predictors for the accumulation of PAHs in inner root and leaf tissue, respectively.

Journal Article↗

PubMed1998

Transesophageal ultrasonographic imaging in rat hearts: visualization of aortic valve vegetations in non-bacterial thrombotic endocarditis.

The aim of this study was to test the feasibility of transesophageal ultrasonography in rats by using an intravascular ultrasound system for visualization of vegetations at the aortic valve in the animal model of experimental endocarditis. After anesthesia and preparation of the right carotid artery, a polyethylene catheter was advanced across the aortic valve into the left ventricle in 91 rats. For transesophageal ultrasonography an intravascular ultrasound catheter (3.5 French; 30 MHz) linked to an imaging system was introduced into the esophagus. Sonographic investigations were performed every 24 hours until death. The presence, size, and echogenicity of vegetations were evaluated. Presence and size were compared to autopsy findings. No complications occurred as a result of the sonographic investigation. Left-sided valvular structures were imaged regularly. For detection of vegetations, sensitivity and specificity were 93% and 88%, respectively. Comparing the measurements of the vegetation size the following regression equation was obtained: y = 0.74x + 0.04 (r = 0.89; standard error of estimate = 0.02 cm). Inter- and intraobserver variabilities for sonographic measurements were 8.3% and 6.2%, respectively. Transesophageal ultrasonography permits reliable detection and repetitive accurate quantification of vegetations in the rat model of endocarditis. The technique enhances longitudinal studies of the dynamic process of the growth of vegetations under defined microbial conditions.

Animals↗

PubMed2000

Dorsal induction from dorsal vegetal cells in Xenopus occurs after mid-blastula transition.

We performed some experiments to investigate the temporal and spatial details of the dorsal induction exerted by dorsal vegetal cells in Xenopus embryo. Two dorsal vegetal cells (D1 cells) were transplanted into the ventral vegetal region of a recipient at the 32-cell stage. At various times after transplantation, the ventral animal-equatorial part was explanted and cultured. The explants isolated 5.5 h after transplantation (time 5.5) elongated and formed somites. In RT-PCR analysis, the expression of dorsal gene, chordin was activated in the explants isolated after time 4.0 (about the 4000-cell stage which corresponds to the mid blastula transition (MBT)) at control stage 10. In another series of experiments, ventral animal-equatorial and dorsal vegetal parts were isolated from the 4000-cell stage embryos and they were combined for 2.0-2.5 h. These ventral animal-equatorial explants elongated and formed somites. The chordin expression was also observed in the explants. But the 32- and 256-cell stage dorsal vegetal cells failed to exert the dorsalizing activity within the 2.0-2.5 h of the conjugation. These results suggest that 2 h contact after MBT is necessary and sufficient for the dorsal induction from the dorsal vegetal cells and it occurs as a result of the zygotic gene expression. Consistent with this idea, the zygotic dorsal genes, siamois and chordin were expressed on the upper regions of the transplanted D1 descendants at stage 10. Furthermore, this region began to gastrulate when the D1 cell was transplanted with upside-down orientation. Our data indicate that the upper region of the D1 descendants by itself act as the Spemann organizer rather than the Nieuwkoop center.

Animals↗

PubMed1996

Expression of S9 and actin CyIIa mRNAs reveals dorso-ventral polarity and mesodermal sublineages in the vegetal plate of the sea urchin embryo.

We have used whole amount in situ hybridization to analyze the patterns of expression of two genes, S9 and actin CyIIa, during the development of the sea urchin, Strongylocentrotus purpuratus. We demonstrate that at the late blastula stage, these two mRNAs are expressed specifically by cells of the vegetal plate. Their domains of expression, however, are different. S9 mRNA is broadly distributed within most of the vegetal plate except for the central region, while CyIIa expression is restricted to a population of 10-15 cells in the ventral region of the plate. S9-expressing secondary mesenchyme cells (SMCs) migrate from the vegetal plate into the blastocoel early in gastrulation and later populate the dorsal ectoderm. The numbers, morphology, and migratory behavior of these cells strongly suggest that they are pigment cells. Throughout gastrulation, CyIIa mRNA is expressed by a population of presumptive SMCs at the ventral aspect of the archenteron tip. The pattern of expression of this mRNA is dynamic, however, and by the early pluteus stage, CyIIa mRNA accumulates in primary mesenchyme cells (PMCs), SMCs, and endodermal cells of the gut. When embryos are treated with NiCl2, a compound that has been shown to ventralize other embryonic tissues, CyIIa mRNA is expressed by an increased number of cells in the vegetal plate in a radially symmetrical pattern. The spatial pattern of CyIIa expression provides the first direct molecular evidence that the vegetal plate is polarized along the dorso-ventral (D-V) axis of the embryo. This gene product should be a valuable marker in future studies of D-V axis specification, as it can be detected at earlier developmental stages than existing molecular markers of this axis. Our observations show that the vegetal plate consists of subterritories of gene expression, and provide further support for the view that diversification of the presumptive, non-skeletogenic mesoderm begins prior to the onset of invagination.

Actins↗

PubMed1999

Removal of vegetal yolk causes dorsal deficencies and impairs dorsal-inducing ability of the yolk cell in zebrafish.

To examine the nature of cytoplasm determinants for dorsal specification in zebrafish, we have developed a method in which we remove the vegetal yolk hemisphere of early fertilized eggs (vegetal removed embryos). When the vegetal yolk mass was removed at the 1-cell stage, the embryos frequently exhibited typical ventralized phenotypes: no axial structures developed. The frequency of dorsal defects decreased when the operation was performed at later stages. Furthermore, the yolk cell obtained from the vegetal-removed embryos lost the ability to induce goosecoid in normal blastomeres while the normal yolk cell frequently did so in normal and vegetal-removed embryos. These results suggested that the vegetal yolk cell mass contains the dorsal determinants, and that the dorsal-inducing ability of the yolk cell is dependent on the determinants.

Animals↗

PubMed2003

Magnetic response of soils and vegetation to heavy metal pollution--a case study.

Fast and cost-effective detection of industrial pollution can significantly promote its ecological, economic, and social assessment. A magnetometric method, used for qualitative determination of anthropogenic contamination, meets these requirements but needs further development in more quantitative terms. It could be used successfully in numerous cases when the heavy metals coexist with strongly magnetic iron oxide particles in the source dust. We present an integrated magnetic and geochemical study that examines the utility of magnetometric techniques for rapid, qualitative detection of metallic pollutants in soils and vegetation. The new aspect of our approach, in comparison with previously published articles on this subject, is the combined investigation (magnetic and geochemical) of both soils and vegetation, thus using an additional medium for employing the magnetometry as a pollution proxy at a site. The study area is a small (approximately 3 km2) region in the suburbs of Sofia (Bulgaria), with the main pollution source being a metallurgical factory. Soil samples have been taken from the topmost 20 cm from private gardens, located at different distances from the factory. Vegetation samples were taken from ryegrass (both leaves and roots) and leaves from two kinds of deciduous trees (maple and acacia). The results show that both vegetation and soils are characterized by enhanced magnetic properties, compared to background material, which is due to the presence of magnetite particles of anthropogenic origin accompanying heavy metal emissions. SEM images and microprobe analyses reveal the presence of a significant amount of particles, containing heavy metals (including iron) in vegetation samples taken close to the main pollution source. Correlation analyses show a statistically significant link (correlation coefficients ranging from 0.6 to 0.7) between magnetic susceptibility and the main heavy metals (Cu, Zn, Pb) in soil samples, indicating that the magnetic susceptibility can provide a proxy method for identifying the relative contribution of industrial pollution in soils and vegetation, that is reliable, inexpensive, and less time-consuming than standard chemical analyses.

Environmental Monitoring↗

PubMed2000

Men who consume vegetable oils rich in monounsaturated fat: their dietary patterns and risk of prostate cancer (New Zealand).

OBJECTIVES: To investigate (i) dietary patterns associated with consumption of vegetable oils rich in monounsaturated fatty acids (MUFA), and (ii) the risk of prostate cancer associated with consumption of these oils. METHODS: A population-based case-control study was conducted in Auckland, New Zealand, involving 317 prostate cancer cases and 480 controls. A food-frequency questionnaire was used to collect data concerning consumption of MUFA-rich vegetable oils (including olive oil, canola or peanut oil) and other dietary variables. Biomarkers for fatty acids were measured in erythrocytes. RESULTS: The group of participants who reported regular consumption of greater than 5.5 ml of MUFA-rich vegetable oils per day had a diet relatively high in monounsaturated fat, vegetables, lycopene, vitamin E, selenium, and n-3 fish oils. Increasing levels of MUFA-rich vegetable oil intake were associated with a progressive reduction in prostate cancer risk (multivariate relative risk = 0.5; 95% confidence interval 0.3-0.9; > 5.5 ml per day vs. nonconsumption, p trend = 0.005), and similar trends were observed across all strata of socioeconomic status. Prostate cancer risk was not associated with intake of total MUFA or the major animal food sources of MUFA. CONCLUSION: This finding may be explained by the protective effect of an associated dietary pattern high in antioxidants and fish oils, an independent protective effect of MUFA-rich vegetable oils unrelated to the MUFA component, or a combination of these factors.

Adult↗

PubMed2002

A pooled analysis of case-control studies of thyroid cancer. VII. Cruciferous and other vegetables (International).

OBJECTIVE: To investigate the association between cruciferous and other vegetables and thyroid cancer risk we systematically reanalyzed the original data from 11 case-control studies conducted in the US, Asia, and Europe. METHODS: A total of 2241 cases (1784 women, 457 men) and 3716 controls (2744 women, 972 men) were included. Odds ratios (OR) and the corresponding 95% confidence intervals (CI) were estimated for each study by logistic regression models, conditioned on age and sex, and adjusted for history of goiter, thyroid nodules or adenomas, and radiation. Summary ORs for all studies combined were computed as the weighted average of the estimates from each study. RESULTS: A decreased risk for the highest level of cruciferous vegetable intake, as compared to the lowest, was observed in Los Angeles, Hawaii, Connecticut, southeastern Sweden, Tromsø, and Switzerland; the OR were above unity in Japan and Uppsala, whereas no material association was found in northern Sweden, Italy, or Greece. The OR values for all studies combined were 0.87 (95% CI 0.75-1.01) for moderate and 0.94 (95% CI 0.80-1.10) for high cruciferous vegetables intake. The results were similar in studies from iodine-rich areas and endemic goiter areas, and were consistent when the analysis was restricted to papillary carcinomas and women. The summary OR values for vegetables other than cruciferous were 1.04 (0.88-1.22) for moderate and 0.82 (0.69-0.98) for high consumption. CONCLUSIONS: This combined analysis indicates that cruciferous vegetables are not positively related to thyroid cancer risk. Their effect does not seem to be substantially different from that of other vegetables, which appear to be protective on this cancer.

Brassica↗

PubMed2003

Sensitivity of transthoracic versus transesophageal echocardiography for the detection of native valve vegetations in the modern era.

BACKGROUND: Thirteen years ago, transthoracic echocardiography (TTE) was found to be less sensitive than transesophageal echocardiography (TEE) for native valve vegetations. Since then, harmonic imaging and other advances have improved TTE. How this affects the sensitivity of TTE is unknown. METHODS: Fifty patients with echocardiography-diagnosed endocarditis had TTE and TEE examinations on high-end machines. These were matched for date of study with 50 patients who had TTE and TEE examinations that were negative for vegetations. RESULTS: A total of 51 vegetations were seen on TEE. The sensitivity of TTE for vegetations was only 55% (aortic 50% [12/24]; mitral 62% [16/26]; tricuspid 0% [0/1]). Anatomic valvular abnormalities did not alter the sensitivity of TTE (P =.42 for mitral; P =.97 for aortic valves). However, larger vegetations were more likely to be found by TTE. CONCLUSION: Despite advances in imaging during 12 years, TTE is still insensitive compared with TEE for the detection of native valve vegetations, and fails to demonstrate nearly half of them.

Aged↗

PubMed1989

Lithium evokes expression of vegetal-specific molecules in the animal blastomeres of sea urchin embryos.

The mechanism of determination of early embryonic cells has been investigated using sea urchin embryos. An efficacious method of isolating blastomere pairs from the animal or vegetal half of sea urchin embryos was developed. The overt differentiation of separated animal and vegetal blastomere pairs resembles that of separated animal and vegetal hemispheres isolated by manual dissection. Treatment of animal blastomeres with LiCl caused them to display a morphology resembling that of isolated vegetal blastomeres. The effects of separation of animal and vegetal blastomeres and of treatment of animal blastomeres with LiCl were examined at the molecular level using gut alkaline phosphatase and a spicule matrix protein RNA as markers of differentiation. Histochemical staining and in situ hybridization studies showed that these markers are normally only expressed in vegetal blastomeres but that their expression can be evoked in animal blastomeres by treatment with LiCl.

Alkaline Phosphatase↗

PubMed2001

Using isothiocyanate excretion as a biological marker of Brassica vegetable consumption in epidemiological studies: evaluating the sources of variability.

OBJECTIVE: Brassica vegetable consumption (e.g. broccoli) leads to excretion of isothiocyanates (ITC) in urine. We evaluated the consistency of ITC as a biomarker for dietary Brassica vegetable consumption across the types of vegetables and methods of preparation used in Western societies, and across consumption levels. DESIGN: A single-armed behavioural intervention with duplicate baseline assessment and post-intervention assessment. Urinary ITC excretion and estrogen metabolites were measured from 24-hour urine samples. Dietary intake was measured by a 24-hour recall. SETTING: The behavioural intervention facilitated daily Brassica intake among participants by providing peer support, food preparation instruction, guided practice in a teaching kitchen, and other information. SUBJECTS: Thirty-four healthy free-living postmenopausal women who recently had a negative screening mammogram at the University of Massachusetts Medical Center. RESULTS: Urinary ITC excretion and total Brassica intake followed the same pattern over the intervention. The ITC biomarker significantly predicted Brassica intake when Brassica consumption averaged about 100 g day-1, but not when Brassica consumption averaged about 200 g day-1. Urinary ITC levels were somewhat higher when more raw vegetables were consumed as compared to lightly cooked vegetables, while the types of Brassica consumed appeared to have only a small, non-significant effect on urinary ITC levels. CONCLUSION: Urinary ITC excretion would be a good exposure biomarker among populations regularly consuming a vegetable serving/day, but may be less accurate among populations with greater intake levels or a wide range of cooking practices.

Aged↗

PubMed2006

Evolutionary history of vegetative reproduction in Porpidia s.L. (Lichen-forming ascomycota).

The evolutionary history of gains and losses of vegetative reproductive propagules (soredia) in Porpidia s.l., a group of lichen-forming ascomycetes, was clarified using Bayesian Markov chain Monte Carlo (MCMC) approaches to monophyly tests and a combined MCMC and maximum likelihood approach to ancestral character state reconstructions. The MCMC framework provided confidence estimates for the reconstructions of relationships and ancestral character states, which formed the basis for tests of evolutionary hypotheses. Monophyly tests rejected all hypotheses that predicted any clustering of reproductive modes in extant taxa. In addition, a nearest-neighbor statistic could not reject the hypothesis that the vegetative reproductive mode is randomly distributed throughout the group. These results show that transitions between presence and absence of the vegetative reproductive mode within Porpidia s.l. occurred several times and independently of each other. Likelihood reconstructions of ancestral character states at selected nodes suggest that--contrary to previous thought--the ancestor to Porpidia s.l. already possessed the vegetative reproductive mode. Furthermore, transition rates are reconstructed asymmetrically with the vegetative reproductive mode being gained at a much lower rate than it is lost. A cautious note has to be added, because a simulation study showed that the ancestral character state reconstructions were highly dependent on taxon sampling. However, our central conclusions, particularly the higher rate of change from vegetative reproductive mode present to absent than vice versa within Porpidia s.l., were found to be broadly independent of taxon sampling.

Ascomycota↗

PubMed1993

Establishing relevant ozone standards to protect vegetation and human health: exposure/dose-response considerations.

For assessing the efficacy of a specific form of the National Ambient Air Quality Standard for O3, those exposure patterns that result in vegetation and human health effects must be identified. For vegetation, it has been found that the higher hourly average concentrations should be weighted more than the lower concentrations. Controlled human exposure work supports the suggestion that concentration may be more important than exposure duration and ventilation rates. It has been indicated in the literature that the current form of the federal O3 standard may not be appropriate for protecting vegetation and human health from O3 exposures. The proposed use of the cumulative index alone as a form of the standard may not provide sufficient protection to vegetation. An extended-period average index, such as a daily maximum 8-hour average concentration, may not be appropriate to protect human health because of the reduced ability to observe differences among hourly O3 concentrations exhibited within exposure regimes. For both vegetation and human health effects research, additional experimentation is required to identify differences in responses that occur when ambient-type exposure regimes are applied. Any standard promulgated to protect vegetation and human health from O3 exposures should consider combining cumulative exposure indices with other parameters so that those unique exposures that have the potential for eliciting an adverse effect can be adequately described.

Air Pollution↗

PubMed1999

MOD-D, a Galpha subunit of the fungus Podospora anserina, is involved in both regulation of development and vegetative incompatibility.

Cell death via vegetative incompatibility is widespread in fungi but molecular mechanism and biological function of the process are poorly understood. One way to investigate this phenomenon was to study genes named mod that modified incompatibility reaction. In this study, we cloned the mod-D gene that encodes a Galpha protein. The mod-D mutant strains present developmental defects. Previously, we showed that the mod-E gene encodes an HSP90. The mod-E1 mutation suppresses both vegetative incompatibility and developmental defects due to the mod-D mutation. Moreover, we isolated the PaAC gene, which encodes an adenylate cyclase, as a partial suppressor of the mod-D1 mutation. Our previous results showed that the molecular mechanisms involved in vegetative incompatibility and developmental pathways are connected, suggesting that vegetative incompatibility may result from disorders in some developmental steps. Our new result corroborates the involvement of mod genes in signal transduction pathways. As expected, we showed that an increase in the cAMP level is able to suppress the defects in vegetative growth due to the mod-D1 mutation. However, cAMP increase has no influence on the suppressor effect of the mod-D1 mutation on vegetative incompatibility, suggesting that this suppressor effect is independent of the cAMP pathway.

Alleles↗

PubMed1988

Effects of tissue-type plasminogen activator (t-PA) on Streptococcus sanguis-infected endocardial vegetations in vitro.

The effects were studied of in-vitro exposure to tissue-type plasminogen activator (t-PA) on endocardial vegetations isolated from rabbits with Streptococcus sanguis endocarditis as well as on Str. sanguis-infected plasma clots. For both vegetations and clots t-PA induced lysis of the infected fibrin matrix, demonstrated by a release of streptococci into the incubation medium and by an increase in the concentration of fibrin degradation products. The clots decreased in weight, whereas only partial lysis of the vegetations was obtained. Addition of plasminogen to the incubation medium did not enhance the effect of t-PA on vegetations. Fibrinolysis by t-PA did not interfere with the antimicrobial action of benzylpenicillin on the bacteria in a fibrin matrix. It is concluded that t-PA can degrade the fibrin matrices of infected endocardial vegetations and plasma clots. Reduction of vegetation size by t-PA may prove to be useful in the treatment of bacterial endocarditis.

Animals↗

PubMed1996

The protein efficiency ratios of 30:70 mixtures of animal:vegetable protein are similar or higher than those of the animal foods alone.

Animal foods in general are considered to be foods with high protein qualities, although their qualities are not always similar because of differences in essential amino acids. The purpose of this study was to compare the protein quality of different animal foods and of their mixtures with vegetable foods, mainly cereals, at the 30:70 animal:vegetable protein proportion with experiments performed under the same conditions. The animal foods were eggs, beef, pork, barbecued lamb, chicken, ham, sausage and milk powder. The vegetable foods used in the mixtures were rice, lime-treated corn flour, wheat flour and cooked black beans. The protein concentrations in the raw and cooked materials were analyzed. The protein efficiency ratios (PER) and digestibilities were determined in Fisher 344 weanling rats. Based on the corrected PER, the foods with the best protein quality were egg (3.24), sirloin beef (3.16), lamb (3.11) and chicken breast (3.07), which were significantly different (P < 0.05) from milk powder (2.88) and beef liver and beef round (2.81 and 2.70, respectively). The ham (2.63) and the pork loin (2.57) had a similar protein quality to that of casein (2.50). The lowest protein quality was found in sausages (2.14). In most of the mixtures of animal and vegetable protein (30:70), the PER was similar to or higher than that of the animal food alone. Beans were the vegetable food that showed the lowest response to the addition of animal food. The conclusion of the study is that some 30:70 mixtures of animal:vegetable protein, such as chicken, beef round and pork with cereals could be utilized for regular meals because of their high PER and low cost.

Animals↗

PubMed1983

Metabolism of carbon and nitrogen by soybean seedlings in response to vegetative apex removal.

Short-term (31-hour diurnal) growth-chamber studies were conducted to determine the effects of removing the vegetative apex (meristem and developing trifoliolate leaves) on net photosynthesis (changes in plant dry weight), on distribution of metabolites among plant parts, and on nitrate metabolism and reduced-N accumulation by soybean [Glycine max (L.) Merr.] seedlings. Roots and stems served as alternate sinks for dry matter accumulation in the absence of the vegetative apex. Sugar concentration in roots increased (42%) within 4 hours of vegetative apex removal, and remained higher than for the controls during the 31-hour experimental period. Nitrate assimilation (nitrate reductase activity and total accumulation of reduced-N) was also enhanced in response to vegetative apex removal. Although dry matter accumulation was similar between treated and control plants (113 versus 116 milligrams per plant) over the 31-hour sampling period, more nitrate (1.31 versus 0.79 milligrams per plant) and more reduced-N (3.96 versus 3.45 milligrams per plant) accumulated in treated plants during the same interval. It was concluded that vegetative apex removal had little effect on overall net photosynthesis of soybean seedlings during the 31-hour treatment period, but did alter partitioning of photosynthate and enhanced uptake, transport, and reduction of nitrate. Implications are that uptake and metabolism of nitrate by soybeans may be limited by flux of carbohydrate to the roots, although hormonal effects due to vegetative apex removal cannot be ruled out.

Journal Article↗

PubMed1998

A recessive heterochronic mutation, plastochron1, shortens the plastochron and elongates the vegetative phase in rice

We describe two recessive alleles of a rice heterochronic gene, plastochron1-1 (pla1-1) and pla1-2, that reduce the length of the plastochron to approximately half that of the wild type. Because the onset of the reproductive phase in pla1 was not temporally affected, the number of leaves produced in the vegetative phase was nearly twice that produced in the wild type. Panicle development was severely disturbed in pla1 mutants. In pla1-1, many primordia of primary rachis branches were converted into vegetative shoots. These ectopic shoots repeated the initiation of panicle development and the conversion of primary rachis branches into shoots. In the weak allele pla1-2, however, only the basal one or two primordia developed as vegetative shoots, and the remaining primordia developed to produce a truncated panicle. These results indicate that both vegetative and reproductive programs are expressed simultaneously during the reproductive phase of pla1; however, the degree varied depending on the strength of the allele. Accordingly, pla1 is a heterochronic mutation that extends the vegetative period. The shoot apical meristem of pla1 was larger than that of the wild type, although the shape was not modified. An in situ hybridization experiment using the histone H4 gene as a probe revealed that cell divisions are accelerated in the pla1 meristem. The PLA1 gene is considered to regulate the duration of the vegetative phase by controlling the rate of leaf production in the meristem.

Journal Article↗