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Other Environmental Factors (other + environmental_factor)
Selected AbstractsThe ultrastructure of chilling stressPLANT CELL & ENVIRONMENT, Issue 4 2000H. A. Kratsch ABSTRACT Chilling injury to crop plants was first described 70 years ago and has been systematically investigated with electron microscopy since the late 1960s. Chloroplasts are the first and most severely impacted organelle. Thylakoids swell and distort, starch granules disappear, and a peripheral reticulum (vesicles arising from inner membrane of chloroplast envelope) appears. Chloroplast disintegration follows prolonged chilling. Mitochondria, nuclei and other organelles are less susceptible to chilling injury. Organellar development and ontogeny may also be disrupted. The inherent chilling sensitivity of a plant, as well as the ability of some species to acclimate to chilling, influence the timing and appearance of ultrastructural injury with the resulting outcome being mild, moderate, or severe. Other environmental factors that exacerbate injury are irradiance, chilling duration, and water status. The physiological basis for chloroplast swelling may be linked to chilling-stable starch-degrading enzymes that produce soluble sugars thus lowering stromal water potential at a time when chloroplast photosynthate export is reduced. Thylakoid dilation appears to be related to photo-oxidative conditions produced during chilling in the light. The peripheral reticulum is proposed to increase surface area of the transport-limiting membrane (chloroplast inner membrane) in response to the chilling-induced reduction in metabolite transport. Many of the ultrastructural symptoms appearing during moderate stress resemble those seen in programmed cell death. Future research directions are discussed. [source] Influence of seasonal, diel, lunar, and other environmental factors on upstream fish passage in the Igarapava Fish Ladder, BrazilECOLOGY OF FRESHWATER FISH, Issue 3 2009P. M. Bizzotto Abstract,,, Upstream fish passage was evaluated during 12 months in the vertical-slot Igarapava Fish Ladder constructed around Igarapava Dam, in the heavily dammed Grande River, Southeast Brazil. A video monitoring system was used to observe 61,621 fish that passed the ladder, of which 93.5% were identified to 15 taxa. Among the migratory species, the most abundant were Pimelodus maculatus (33.6% of all fish), Leporinus octofasciatus (31.4%), Leporinus friderici (4.5%), and Prochilodus lineatus (3.1%). Seven taxa were classified as nonmigratory, and of these taxa, the small Bryconamericus stramineus was the most abundant (12.7%) of all fishes. Passage of the ,nonmigratory' taxa upstream in the ladder shows they are migratory in this system and have a strong behavioural drive to move to upstream habitat. Passage of most taxa had a strong seasonal pattern. While some species passed primarily during the day, others showed a distinct nocturnal pattern. Lunar phase and water temperature also strongly affected passage of some taxa. Rainfall and dam discharge had a small or null influence on most taxa; perhaps due to the fairly small catchment area of the reservoir and the highly regulated discharge at Igarapava Dam. [source] Interaction of an insecticide with larval density in pond-breeding salamanders (Ambystoma)FRESHWATER BIOLOGY, Issue 4 2005BRIAN S. METTS Summary 1. Amphibian populations residing in or near agricultural areas are often susceptible to pesticide contamination. Recent evidence suggests that the effects of pesticides on amphibians often exceed those estimated in laboratory toxicity tests because other environmental factors (e.g. predators, resource abundance) can influence pesticide toxicity. 2. To examine the effects of an insecticide (carbaryl) on two species of Ambystoma salamanders experiencing the natural stress of competition, we manipulated chemical concentration (control, 3.5 and 7.0 mg L,1) and larval density (low and high). We determined the effect of treatments on snout-vent length (SVL), growth rate, lipid reserves, time to metamorphosis, per cent survival and per cent metamorphosis. 3. Carbaryl negatively affected all response variables of Ambystoma maculatum significantly, and significantly reduced survival and metamorphosis of A. opacum. Increased density significantly influenced SVL, lipid reserves, growth rate and metamorphosis of A. maculatum. 4. The effects of carbaryl and increased density on per cent metamorphosis were nearly additive, but were generally less than additive on other variables. 5. The negative effects of chemical contamination on salamanders were likely because of pesticide-induced reductions of food resources, as zooplankton abundance decreased by as much as 97% following carbaryl application. 6. Our study demonstrates the importance of the interactive effects that chemical contamination and natural environmental factors have on salamanders. [source] Epidemiology Of Hodgkin's disease: a reviewHEMATOLOGICAL ONCOLOGY, Issue 1 2004R. A. Cartwright Abstract The descriptive and aetiological epidemiology of Hodgkin's Disease (HD) are reviewed. Key issues which are highlighted include the evidence suggesting that HD is a complex of related conditions that are part mediated by infectious diseases, immune deficits and genetic susceptibilities. There is little convincing evidence to suggest any other environmental factors are involved in the aetiology. The apparent changing pattern of disease by time and from country to country, needs careful future study. Copyright © 2004 John Wiley & Sons, Ltd. [source] Preterm birth but not mode of delivery is associated with an increased risk of developing inflammatory bowel disease later in lifeINFLAMMATORY BOWEL DISEASES, Issue 11 2007Barbara Sonntag MD Abstract Background: Exposure to bacterial antigens and other environmental factors in combination with a genetic susceptibility have been implicated in the etiology of inflammatory bowel disease (IBD). As certain perinatal circumstances, e.g., delivery by cesarean section, predispose to a different intestinal colonizations the aim of this analysis was to define a potential influence on the development of IBD in later life. Methods: In a case-control study design, birth data were recorded from patients diagnosed with IBD (Crohn's disease [CD], n = 1096; ulcerative colitis [UC], n = 763) and healthy controls ([C], n = 878) by a self-administered questionnaire. Results: Preterm birth (CD: odds ratio [OR] 1.5 [95% confidence interval 1.1,2.0], UC: OR 1.3 [0.9,1.9]), mother's disease during pregnancy (CD: OR 1.9 [1.3,2.9], UC: OR 1.6 [1.0,2.4]), and disease in the first year of life (CD: OR 2.2 [1.6,2.9], UC: OR 1.7 [1.3,2.3]) are associated with the development of IBD in later life. No significant associations were found for the mode of delivery and breast feeding. In a logistic regression analysis female sex, smoking, appendectomy, maternal IBD, and disease in the first year of life were independently associated with CD. Female sex, appendectomy, and disease in the first year of life were independently associated with UC. Conclusions: Preterm birth and other perinatal circumstances are associated with the development of IBD, of which disease in the first year of life is an independent risk factor in multivariate analysis. (Inflamm Bowel Dis 2007) [source] Nickel hypersensitivity: a clinical review and call to actionINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 2 2010Sarah E. Schram MD Nickel sensitivity is common and increasing in prevalence. This review discusses nickel sensitivity and its association with body piercing and other environmental factors, occupational relevance, and potential implications for implantable metal medical devices. In addition, current European legislation that limits the release of nickel from jewelry is highlighted and an argument for similar legislation elsewhere is presented. [source] Synergistic, antagonistic and additive effects of multiple stressors: predation threat, parasitism and pesticide exposure in Daphnia magnaJOURNAL OF APPLIED ECOLOGY, Issue 6 2008Anja Coors Summary 1Predation and parasitism are important factors in the ecology and evolution of natural populations and may, along with other environmental factors, interact with the impact of anthropogenic pollutants. 2Our study aimed at identifying potential interactions between three stressors (predation threat, parasitism and pesticide exposure) and at exploring the predictability of their joint effects by using the model of independent action. We assessed in a full-factorial design the impacts of these stressors on key life-history traits and population growth rate of the water flea Daphnia magna. 3When applied as single stressors, predation threat and parasite challenge induced varying stressor-specific adaptive responses. The pesticide carbaryl was applied at a generally sublethal concentration, which caused low mortality only in first-brood offspring. 4Pesticide exposure interacted synergistically with parasite challenge regarding survival, which suggests immunomodulatory activity of the pesticide. Predation threat by phantom midge larvae showed antagonistic interactions for amount of first-brood offspring with both parasite challenge and carbaryl exposure. All stressors additively affected age and size at maturity, which added up to a considerable delay in the onset of reproduction in the three-stressor combination. The intrinsic rate of natural increase, r, reflected the non-additive and additive effects on single endpoints and showed significant synergistic interactions for all two-stressor combinations. The combination of all stressors resulted in a dramatic reduction of r compared to the stressor-free control. 5The model of independent action proved useful in quantitatively predicting effects of additively acting stressors, and in visualizing the occurrence and magnitude of non-additive effects in accordance with results of analysis of variances. 6Synthesis and applications. Cumulative additive effects and non-additive interactions of natural antagonists and pollutants are shown to result in considerable impacts on ecologically relevant parameters. As a starting point for an environmentally more realistic risk assessment of chemicals, it may be a valuable strategy to screen for non-additive effects among many stress factors simultaneously in simplified experimental designs by using the model of independent action. [source] A comparison of regeneration dynamics following gap creation at two geographically contrasting heathland sitesJOURNAL OF APPLIED ECOLOGY, Issue 5 2000A.J. Britton 1.,Lowland Calluna -dominated heathlands are a high priority for conservation in Europe. As an anthropogenic subclimax community they require regular management intervention to maintain their conservation interest. 2.,Increasingly, Calluna is disappearing from lowland heathlands and being replaced by grasses, especially in the Netherlands and more recently in south-east England. While Calluna is highly competitive over much of its life cycle, its competitive ability is reduced during the regeneration phase that follows the death of stands or results from management activity. 3.,We examined the influence of five factors on regeneration of vegetation in gaps in two broadly similar lowland dry heaths over a 3-year period. These were: geographical location (combining a variety of environmental contrasts); dominant species (Calluna or grasses); management techniques; gap size; and seed source availability. 4.,Site location had the greatest effect on patterns of regeneration. Regeneration on the Wirral (north-west England) was faster and more dominated by Calluna than regeneration in Breckland (south-east England), which was dominated by other species including grasses and annual plants. Addition of Calluna seed at the Breckland site failed to increase Calluna cover. It was concluded that climatic or other environmental factors were the most probable cause of poor regeneration. 5.,Cover of grasses in regenerating areas was greatest in Breckland, where Deschampsia was able to establish in all gaps where there was a seed source (either in the surrounding vegetation or applied as a treatment). On the Wirral, Deschampsia establishment was limited, even in gaps where a seed source was applied. 6.,This work has implications for the conservation management of heathlands, which currently follows a standard prescription throughout the UK. It is suggested that management regimes should be tailored to suit the conditions prevailing at individual sites as regeneration dynamics may be extremely variable. [source] The potential role of plant oxygen and sulphide dynamics in die-off events of the tropical seagrass, Thalassia testudinumJOURNAL OF ECOLOGY, Issue 1 2005J. BORUM Summary 1Oxygen and sulphide dynamics were examined, using microelectrode techniques, in meristems and rhizomes of the seagrass Thalassia testudinum at three different sites in Florida Bay, and in the laboratory, to evaluate the potential role of internal oxygen variability and sulphide invasion in episodes of sudden die-off. The sites differed with respect to shoot density and sediment composition, with an active die-off occurring at only one of the sites. 2Meristematic oxygen content followed similar diel patterns at all sites with high oxygen content during the day and hyposaturation relative to the water column during the night. Minimum meristematic oxygen content was recorded around sunrise and varied among sites, with values close to zero at the die-off site. 3Gaseous sulphide was detected within the sediment at all sites but at different concentrations among sites and within the die-off site. Spontaneous invasion of sulphide into Thalassia rhizomes was recorded at low internal oxygen partial pressure during darkness at the die-off site. 4A laboratory experiment showed that the internal oxygen dynamics depended on light availability, and hence plant photosynthesis, and on the oxygen content of the water column controlling passive oxygen diffusion from water column to leaves and below-ground tissues in the dark. 5Sulphide invasion only occurred at low internal oxygen content, and the rate of invasion was highly dependent on the oxygen supply to roots and rhizomes. Sulphide was slowly depleted from the tissues when high oxygen partial pressures were re-established through leaf photosynthesis. Coexistence of sulphide and oxygen in the tissues and the slow rate of sulphide depletion suggest that sulphide reoxidation is not biologically mediated within the tissues of Thalassia. 6Our results support the hypothesis that internal oxygen stress, caused by low water column oxygen content or poor plant performance governed by other environmental factors, allows invasion of sulphide and that the internal plant oxygen and sulphide dynamics potentially are key factors in the episodes of sudden die-off in beds of Thalassia testudinum. Root anoxia followed by sulphide invasion may be a more general mechanism determining the growth and survival of other rooted plants in sulphate-rich aquatic environments. [source] Low-level lead exposure and childrenJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 5 2001NR Wigg Abstract: The adverse effects of environmental lead exposure on the mental development of young children are well established. There is no safe level of blood lead below which children are not affected. Recent research expands our understanding of the impact of lead exposure continuing into later childhood, as well as its effects on children's behaviour. However, social and other environmental factors also contribute to variance in measures of developmental and behavioural outcomes. Lead is associated with only modest effects on children's development, but is a potentially modifiable risk factor. As environmental exposure to lead declines for the whole population, continued specific attention is needed for children living in industrial areas. [source] Stimulatory Effect of Procaine on the Growth of Several Microalgae and CyanobacteriaJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 2 2000TAKAHIRO SUZUKI Procaine has been used to stimulate plant growth and it has been noted that it also promotes growth of microorganisms. The effect of procaine hydrochloride concentration on the growth rates of several species of microalgae and cyanobacteria was studied under both photoautotropic and heterotrophic growth conditions. Procaine hydrochloride was added to cultures at concentrations over the range 0.01,1000 mg L,1. A stimulating effect of procaine hydrochloride on photoautotrophic growth was observed for the cyanobacteria Anabaena cylindrica and Anabaena variabilis, and for the salt-tolerant green algae Dunaliella primolecta and Dunaliella parva. During active growth in batch culture an increase in growth rate (compared with control culture without procaine hydrochloride) of about 25% was observed at 0.1 mg L,1 of procaine hydrochloride for A. cylindrica. However, procaine hydrochloride was toxic at concentrations of > 10 mg L,1. Simultaneous administration of hydrolysis products of procaine, p -amino-benzoic acid and diethyl aminoethanol, in lieu of procaine hydrochloride, was as effective as procaine in stimulating growth of A. cylindrica. Heterotrophic growth of Chlorella ellipsoidea and Prototheca zopfii was not stimulated by procaine hydrochloride over the concentration range studied (0.1,10 mg L,1). The combined effects of procaine hydrochloride concentration and four other environmental factors (temperature, light intensity, CO2 concentration in the flushing gas and NaCl concentration) on growth rate of D. primolecta was modelled using both a neural network approach and a response surface method. These results indicate that procaine hydrochloride exerts different effects on the growth of microalgal and cyanobacterial cells as functions of dosage, species and culture conditions. [source] An epidemiological study of environmental factors associated with canine obesityJOURNAL OF SMALL ANIMAL PRACTICE, Issue 7 2010E. A. Courcier Objectives: To assess the relationships between socioeconomic and other environmental factors with canine obesity. Methods: This was a cross-sectional questionnaire study of dog owners attending five primary veterinary practices in the UK. Owners were asked about dog age, neuter status, feeding habits, dog exercise, household income and owner age. The body condition score of the dogs was also assessed. Factors hypothesised to be associated with obesity were investigated. Results: In total, data from 696 questionnaires were evaluated. Out of those data evaluated, 35·3% of dogs (n=246) were classed as an ideal body shape, 38·9% (n=271) were overweight, 20·4% (n=142) were obese and 5·3% (n=37) were underweight. Identified risk factors associated with obesity included owner age, hours of weekly exercise, frequency of snacks/treats and personal income. Clinical Significance: Environmental risk factors associated with canine obesity are multifactorial and include personal income, owner age, frequency of snacks/treats and amount of exercise the dog receives. Awareness about health risks associated with obesity in dogs is significantly less in people in lower income brackets. This phenomenon is recognised in human obesity. [source] Ecology of an anchialine cave in the Adriatic Sea with special reference to its thermal regimeMARINE ECOLOGY, Issue 2007Maja Novosel Abstract This study examines the ecology and thermal regime in the ,iva Voda anchialine cave on Hvar Island (Adriatic Sea, Croatia). The cave, which has no direct connections with the open sea, contains a dense population of the deep-sea hexactinellid sponge Oopsacas minuta Topsent, 1927. Several species of polychaetes, molluscs and crustaceans were also recorded. Two-year temperature data recorded simultaneously at two depths within the cave and at a nearby outside site provide information on thermal conditions in the system. The temperature oscillations within the cave are strongly dampened , varying from 14.6 °C in winter to 17.9 °C in summer , the annual range being four times smaller than in the adjoining sea. These data suggest that O. minuta can withstand higher temperatures than previously expected from deep-sea or cold-water cave occurrences, and that other environmental factors must be playing an important role. [source] Field studies on the environmental fate of the Cry1Ab Bt-toxin produced by transgenic maize (MON810) and its effect on bacterial communities in the maize rhizosphereMOLECULAR ECOLOGY, Issue 8 2005SUSANNE BAUMGARTE Abstract Field studies were done to assess how much of the transgenic, insecticidal protein, Cry1Ab, encoded by a truncated cry1Ab gene from Bacillus thuringiensis (Bt), was released from Bt-maize MON810 into soil and whether bacterial communities inhabiting the rhizosphere of MON810 maize were different from those of the rhizosphere of nontransgenic maize cultivars. Bacterial community structure was investigated by SSCP (single-strand conformation polymorphism) of PCR-amplified 16S rRNA genes from community DNA. Using an improved extraction and detection protocol based on a commercially available ELISA, it was possible to detect Cry1Ab protein extracted from soils to a threshold concentration of 0.07 ng/g soil. From 100 ng of purified Cry1Ab protein added per gram of soil, only an average of 37% was extractable. At both field sites investigated, the amount of Cry1Ab protein in bulk soil of MON810 field plots was always lower than in the rhizosphere, the latter ranging from 0.1 to 10 ng/g soil. Immunoreactive Cry1Ab protein was also detected at 0.21 ng/g bulk soil 7 months after harvesting, i.e. in April of the following year. At this time, however, higher values were found in residues of leaves (21 ng/g) and of roots (183 ng/g), the latter corresponding to 12% of the Cry1Ab protein present in intact roots. A sampling 2 months later indicated further degradation of the protein. Despite the detection of Cry1Ab protein in the rhizosphere of MON810 maize, the bacterial community structure was less affected by the Cry1Ab protein than by other environmental factors, i.e. the age of the plants or field heterogeneities. The persistence of Cry1Ab protein emphasizes the importance of considering post-harvest effects on nontarget organisms. [source] Why does elevated CO2 affect time of flowering?NEW PHYTOLOGIST, Issue 2 2009An exploratory study using the photoperiodic flowering mutants of Arabidopsis thaliana Summary ,,Evidence is accumulating that the effect of CO2 on time of flowering involves interactions with photoperiod, but the basis for this interaction is unclear. Here, which components of the photoperiod flowering pathway account for this interaction in Arabidopsis thaliana were examined. ,,Ten mutants deficient in particular loci in the photoperiod pathway, as well as the wild type, were grown under short and long days at either ambient or elevated CO2. Leaf number at flowering and the number of days required for induction of flowering were determined. ,,Elevated CO2 interacted with both the photoreceptors and the subsequent transduction reactions in the photoperiod pathway. The direction and magnitude of the effects varied with photoperiod. Elevated CO2 also affected flowering by increasing rate of leaf production. ,,The net effect of elevated CO2 on time of flowering varies because CO2 has a complex array of effects on different elements of the developmental pathway leading to flower induction that may either hasten or delay flowering depending upon the influence of other environmental factors such as photoperiod. [source] Epigenetic effects of infection on the phenotype of host offspring: parasites reaching across host generationsOIKOS, Issue 3 2008Robert Poulin Parasite-induced changes in host phenotype are now well-documented from a wide range of taxa. There is a growing body of evidence indicating that parasites can also have trans-generational consequences, with infection of a host leading to changes in the phenotype of its offspring, though the latter are not parasitised. Several proximate mechanisms have been put forward to explain these ,maternal' effects, most involving hormonal or other physiological pathways, ultimately leading to offspring that are pre-adapted to the parasites they are most likely to encounter based on their mother's experience. Here, we propose that all these trans-generational effects on offspring phenotype must involve epigenetic phenomena. Epigenetics concerns the appearance and inheritance of seemingly new phenotypic traits without changes in the underlying DNA sequence. Since diet and other environmental factors experienced by a mother can affect gene expression in her offspring by turning genes ,on' or ,off' (for example, via DNA methylation), why couldn't parasites do it? Although epigenetic effects have not been explicitly invoked to account for trans-generational impacts of parasites on the phenotype of host offspring, the existing evidence is fully compatible with their involvement. We argue that epigenetic mechanisms must play a central role; we also discuss their evolutionary implications and suggest questions for future investigations in this new and exciting research direction. [source] Photosynthetic Acclimation to Simultaneous and Interacting Environmental Stresses Along Natural Light Gradients: Optimality and ConstraintsPLANT BIOLOGY, Issue 3 2004ü. Niinemets Abstract: There is a strong natural light gradient from the top to the bottom in plant canopies and along gap-understorey continua. Leaf structure and photosynthetic capacities change close to proportionally along these gradients, leading to maximisation of whole canopy photosynthesis. However, other environmental factors also vary within the light gradients in a correlative manner. Specifically, the leaves exposed to higher irradiance suffer from more severe heat, water, and photoinhibition stresses. Research in tree canopies and across gap-understorey gradients demonstrates that plants have a large potential to acclimate to interacting environmental limitations. The optimum temperature for photosynthetic electron transport increases with increasing growth irradiance in the canopy, improving the resistance of photosynthetic apparatus to heat stress. Stomatal constraints on photosynthesis are also larger at higher irradiance because the leaves at greater evaporative demands regulate water use more efficiently. Furthermore, upper canopy leaves are more rigid and have lower leaf osmotic potentials to improve water extraction from drying soil. The current review highlights that such an array of complex interactions significantly modifies the potential and realized whole canopy photosynthetic productivity, but also that the interactive effects cannot be simply predicted as composites of additive partial environmental stresses. We hypothesize that plant photosynthetic capacities deviate from the theoretical optimum values because of the interacting stresses in plant canopies and evolutionary trade-offs between leaf- and canopy-level plastic adjustments in light capture and use. [source] Contractile roots in succulent monocots: convergence, divergence and adaptation to limited rainfallPLANT CELL & ENVIRONMENT, Issue 8 2008GRETCHEN B. NORTH ABSTRACT Contractile roots (CRs) that pull shoots further down in the soil are a possible example of convergent evolution in two monocot families, the Agavaceae and the Asphodelaceae. The association between CRs, water uptake and habitat aridity was investigated for agaves, yuccas and aloes by assessing the occurrence of CRs and the amount of root contraction for glasshouse-grown plants with respect to mean annual rainfall of their native habitats. Structural features of CRs as well as root hydraulic conductance were compared with those of non-contractile roots (NCRs). CRs occurred in 55% of the 73 species examined, including 64% of the agaves and 85% of the yuccas, but in none of the aloes despite the occurrence of CRs in related genera. The phylogenetic distribution of CRs was consistent with multiple acquisitions or losses of the trait. The amount of root contraction showed a highly significant negative relationship with mean annual rainfall, although other environmental factors may also be important. Radial hydraulic conductance of the basal (contractile) zone exceeded that of the midroot zone for CRs; for NCRs, the opposite was true. Thus, CRs in the species examined may provide a mechanism for greater water uptake near the soil surface in regions with limited rainfall. [source] Prevalence of Herpes Simplex Virus in Malignant Laryngeal Lesions,THE LARYNGOSCOPE, Issue 2 2000Anna M. Pou MD Abstract Objective: To determine the prevalence of herpes simplex virus (HSV) in malignant laryngeal lesions. Study Design: Retrospective review. Materials and Methods: Paraffin-embedded, histologically confirmed specimens containing benign laryngeal lesions, squamous cell carcinoma of the larynx, and squamous cell carcinoma of the oral cavity were identified from archived surgical specimens. Biopsies of normal-appearing oral cavity tissue were also obtained from fresh-frozen cadavers. These tissues were analyzed for the presence of HSV DNA using polymerase chain reaction techniques. Patient charts were reviewed for patient demographics, risk factors, stage, clinical course, treatment, and outcome. Results: HSV was detected in nine laryngeal squamous cell carcinomas (75%) and in none of the benign laryngeal lesions (P = .0001). HSV was also found in three oral cavity squamous cell carcinomas (25%) and in none of the controls (P = .049). Conclusion: HSV is more prevalent in squamous cell carcinoma of the larynx and oral cavity than in their respective control groups, suggesting a role for carcinogenesis. HSV is more prevalent in squamous cell carcinoma of the larynx than of the oral cavity. Further studies to determine the role of HSV as a cocarcinogen and its interrelationship with other environmental factors in laryngeal cancer are warranted. [source] Plant functional trait variation in relation to riparian geomorphology: The importance of disturbanceAUSTRAL ECOLOGY, Issue 7 2009GARRETH KYLE Abstract This study examined the patterns of plant functional trait variation in relation to geomorphology, disturbance and a suite of other environmental factors in the riparian margin of the Upper Hunter River, New South Wales, Australia. Vegetation was surveyed on three geomorphic surfaces (point bar, bench and bank) along a 5.5-km stretch of the Upper Hunter River. Functional traits relating to plant growth and reproduction were collected for the identified species. anova and principal components analysis were used to compare the trait assemblages of species associated with each geomorphic unit. Pearson's correlation coefficients were used to investigate trait variation with respect to environmental variables. There were clear differences in the plant functional trait assemblages associated with the three geomorphic units. Generally the point bar was associated with species that were herbaceous, with small seed mass, a short stature and a high specific leaf area (SLA). Conversely, the bench was associated with grasses that had unassisted seed dispersal and intermediate seed mass and SLA, while species on the bank had tall stature, large seed mass, a high SLA and a perennial life cycle. Variation along the primary gradient of plant functional trait composition was most strongly related to disturbance frequency and to a lesser extent soil nutrients and the proportion of clay and silt, while variation along the secondary gradient was associated with variation in substrate texture as well as soil nutrients. [source] Food/nutrient intake and risk of atrophic gastritis among the Helicobacter pylori -infected population of northeastern JapanCANCER SCIENCE, Issue 4 2003Ai Montani Although Helicobacter pylori (H. pylori) infection is considered a key risk factor for atrophic gastritis, along with other environmental factors, it is still unclear which factor is involved in the development of atrophic gastritis among H. pylori -infected subjects. In the present cross-sectional study, therefore, we analyzed various dietary factors in relation to the presence of atrophic gastritis among H. pylori -infected subjects who participated in a health check-up program in a town in northeastern Japan. One thousand and seventy-one subjects (362 males and 709 females) who provided both self-administered validated food frequency questionnaires and blood samples were the basis for the study, and all of them were serologically positive for H. pylori immunoglobulin G (IgG) antibody. Among them, 663 (223 males and 440 females) were diagnosed as having atrophic gastritis on the basis of serum pepsinogen levels. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated based on tertile categories of subjects without atrophic gastritis, using logistic regression analysis. Among females, high consumptions of rice (OR=1.6, 95% CI: 1.1,2.3), cod roe (OR=1.5, 95% CI: 1.0,2.2) and cuttlefish (OR=1.5, 95% CI: 1.0,2.3) were associated with a moderately increased risk of atrophic gastritis after adjustment for age (P for trend=0.02 for these items). Among males, high consumptions of rice and miso soup showed a tendency toward an increased risk (P for trend=0.12 and 0.13, respectively). Vegetables and fruits showed no association among either males or females. From these results, it is suggested that the dietary habits of consumers of traditional Japanese foods may play a role in the development of atrophic gastritis after H. pylori infection. (Cancer Sci 2003; 94: 372,377) [source] | |||||||||||||||||||||||||