Unicentric extranodal lymphoma of the upper eyelid conjunctiva in a dog

A case of conjunctival lymphoma in a 4-year-old Siberian husky is reported. A large red mass protruding from the conjunctiva of the upper eyelid of the right eye was present. Irritation, blepharospasm and epiphora were revealed on initial ophthalmic examination. After anti-inflammatory treatment, surgery was performed. Histologically, the mass consisted of large polygonal cells with a high nucleus to cytoplasm ratio, moderate amounts of slightly eosinophilic cytoplasm, pleomorphic nuclei with vesicular chromatin and prominent multiple nucleoli. Mitotic figures were frequent. Approximately 70% of the neoplastic cells were CD3 positive and CD79alpha negative. On the basis of histologic and immunohistochemical findings, a diagnosis of intermediate-grade, diffuse large-cell lymphoma with T-cell immunophenotype was made. The surgical area healed uneventfully and, although chemotherapy was not received, after 12 months the dog exhibited no recurrence. To the authors' knowledge, this is the first report of unicentric extranodal conjunctival lymphoma in a dog.     

Colonist farmers' perceptions of fertility and the frontier environment in eastern Amazonia

Colonists, unlike indigenous peoples, are often assumed tohave little knowledge of their environment. However, their perceptions of the environment and their knowledgeof natural resource systems have a significant impact on their farming practices. Farmers in the frontier regionof Marabá, Eastern Amazonia, understand nutrient cycling and the links between different components in farmingsystems. Diagrams drawn by farmers show very diversified systems, and farmers' knowledge of soilcharacteristics, including sub-surface features, and distribution in their localities is very detailed in comparison to pedologicalclassifications. However, knowledge about nutrient cycling is very uneven, even between farmers from the same area.Generally, farmers were found to have very detailed knowledge of environmental resources, but very patchyknowledge of processes and functions underlying systems, and this conforms to evolutionary models of ecologicalknowledge. Perceptions of change in soil fertility are related to the length of settlement, and are closelylinked to the presence of forest. Overall, the majority of farmers believe they will not be able to sustain cropping in thefuture, and as forest and fallow become scarce the most feasible option will be for them to move to other areas.Farmers are more optimistic about pasture, which is viewed as a more stable system, with the key to long-termsustainability being weed control. These findings imply that a high degree of information sharing between farmers andscientists is required to establish resource management strategies and social institutions to supportsustainable development strategies at the frontier.     

Atmospheric Pollution in a Tropical Rain Forest: Effects of Deposition Upon Biosphere and Hydrosphere I. Concentrations of Chemicals

The effects of atmospheric deposition upon elementcycling and turnover in three rain forest ecosystems ofthe Serra do Mar, a mountain range along the atlanticcoast of Brazil, have been investigated as part of aninterdisciplinary German-Brazilian research project ondispersion, transformation and deposition of airpollutants in the vicinity the industrial complex ofCubatão, State of São Paulo. The projectincluded on-site measurements from 1991 to 1995, fieldexperiments and mathematical modelling with the goalof providing damage evaluation and risk assessment,and elucidating damage mechanisms with respect tosoils and vegetation. The role of the `Soil Module'sub-project reported here was to assess atmosphericdeposition and fluxes with precipitation and soilwater, and to investigate possible soil changesinduced by atmospheric deposition as well asbiological effects of pollutants via the soil path.Part I of this paper deals with concentrations ofchemicals in precipitation, soil water, surface waterand in litter. Part II will cover fluxes of chemicalsand element budgets.Three sites were chosen which differed significantlywith respect to pollution impact. Annual averages ofionic concentrations in precipitation found in openfield and below the tree canopy amounted to 5 and10 mg L<sup>-1</sup>, respectively, for sulfate-S, 0.4 and0.7 mg L<sup>-1</sup> for nitrate, 0.65 and 1.1 mg L<sup>-1</sup> for fluoride,1.8 and 2.6 mg L<sup>-1</sup> for ammonium-N, 0.76 and 2.3 mg L<sup>-1</sup>for Mg, and 3.5 and 7.5 mg L<sup>-1</sup> for Ca at the mostpolluted site. The relatively `clean' reference siteattained 1/3 to 1/9 of these averages, thus clearlyreflecting the difference in air pollution load.Chemical composition in the liquid phase is completelychanged when precipitation infiltrates the soilprofile. Nitrate concentration increases by the factor5 to 20. A clear increase is also found for sulfateand chloride. Concentration changes during ecosystempassage of seepage are interpreted in relation tochemical reactions taking place in differentcompartments. They are characterized by an almostcomplete retention of ammonium and some retention ofsulfate in the upper soil layers, and at the mostpolluted site by mobilization of Al from soil mineralsand very high leaching of nitrate as a consequence ofnitirification of organic matter.     

Long-term study of the reproductive timing of the Neotropical catfish Iheringichthys labrosus (Lütken, 1874): Influence of temperature and river discharge

Unravelling the effect of climate variability on species biology has been one of the main goals of ecological studies. Environmental factors such as river discharge and temperature have being proposed as triggers of reproductive cycle in fish. In temperate climates, fish reproduction is affected mainly by temperature, while is influenced by flood pulses in large tropical rivers. We evaluated the influence of temperature and river discharge as triggers of Iheringichthys labrosus’ reproduction. We studied the following reproductive variables: gonadosomatic index (GSI), hepatosomatic index (HSI) and condition factor (K). Females of I. labrosus were examined in a time series of ten years along three sites located in Lower Uruguay River at the beginning (last week of November-first week of December, spring) and by the end of the reproductive period (middle-end of April, autumn). Generalised linear models detected a positive effect of mean winter temperature and site on the spring mature female GSI. Site was significant in addition to the interaction between temperature and site. Moreover, the effect of winter temperature was stronger than water discharge in triggering reproductive timing of I. labrosus, contrary to the model proposed for other species in tropical systems. Additionally, a literature review suggested a latitudinal gradient on reproduction, occurring earlier and prolonged with decreasing latitude (and increasing temperature). In this study, we stated the effect of temperature on the life history in a Neotropical fish using a multifaceted approach, particularly important in the current context of global climate warming.     

Effect of phase-feeding crude protein on performance and carcass characteristics of crossbred beef bulls: an application to reduce nitrogen compounds in beef cattle diets

Beef cattle (24) with an average initial body weight of 417?±?54 kg were assigned in a 2?×?2 factorial design with six repetitions. The factors studied were two levels of CP: 11 (low CP) or 13 % (high CP) in the initial feedlot phase (days 1–36) and in the final phase (days 37–72). After 36 days, half of the bulls fed with each level of CP were selected to reverse the CP level. No interaction was observed (P?>?0.05) between the level of protein in the initial and final phases on the intake of the nutrients evaluated. There was no effect (P?>?0.05) of the protein levels in the initial and final phases on intake of dry matter, organic matter, CP, non-fiber carbohydrates, and total digestible nutrients. No differences were observed among treatments (P?>?0.05) for average daily gain (X = 1.99 kg/day) and carcass traits. We conclude that it is possible to feed Holstein-Zebu crossed bulls with an average daily gain of approximately 2 kg using a fixed level of 11 % CP during the entire feedlot period, and this diet is economically viable and environmentally sound.     

Acid rain: Threshold of leaf damage in eight plant species from a Southern Appalachian forest succession

Eight plant species were subjected to artifical acid rains of pH 2.5, 2.0, 1.5, 1.0 and 0.5 in order to determine the threshold for and symptoms of damage. The plants were Erechtites, Robinia, Pinus, Quercus, Carya, Liriodendron, Acer and Corpus from the Coweeta Hydrologic Laboratory near Franklin, North Carolina Droplets of pH 2.0 produced brown necrotic spots on all species except Pinus while droplets of pH 1.0 produced necroses on leaves of all species examined. The size of necrotic spots increased with increasing acidity. Comparison of these results with the literature suggests that developing leaves are more easily damaged than are the mature leaves used in this study. The volume weighted average rainfall pH for Coweeta is 4.6 with observations ranging from 3.2 to 5.9. Results of this study suggest that a 10-fold increase in acidity from pH 3.2 to 2.2 in a single spring or summer storm could bring damage or death to mature leaves of dominant flowering plants in the Southern Appalachians.     

Influence of cultivar on quality parameters and chemical composition of strawberry fruits grown in Brazil

Six strawberry cultivars grown on the same commercial plantation in Brazil were evaluated for their chemical composition and quality attributes at the ripe stage. The profiles of the main soluble sugars, ascorbic acid, and anthocyanins were also obtained during the developmental stages. Results showed significant differences among cultivars in all of the investigated parameters. Cv. Campineiro showed an average value for texture of 0.63 N, half the value found for cv. Oso Grande. Anthocyanin content ranged from 13 (cv. Campineiro) to 55 (cv. Mazi) mg/100 g. Total ascorbic acid found for cv. Campineiro (85 mg/100 g) was twice the amount found in cv. Dover (40 mg/100 g). Fructose was the predominant soluble sugar in almost all cultivars. The proportion among the main soluble sugars (fructose, sucrose, and glucose) was similar for Oso Grande and Toyonoka cultivars. The flavonol content (quercetin plus kaempferol derivatives) ranged from 2.7 to 7.1 mg/100 g, with a mean value of 6.1 mg/100 g, whereas free ellagic acid ranged from 0.9 to 1.9 and total phenolics varied from 159 to 289 (mean 221) mg/100 g.     

Honey with high levels of antioxidants can provide protection to healthy human subjects

Free radicals and reactive oxygen species (ROS) have been implicated in contributing to the processes of aging and disease. Humans protect themselves from these damaging compounds, in part, by absorbing antioxidants from high-antioxidant foods. This report describes the effects of consuming 1.5 g/kg body weight of corn syrup or buckwheat honey on the antioxidant and reducing capacities of plasma in healthy human adults. The corn syrup treatment contained 0.21 +/- 0.06 mg of phenolic antioxidants per gram, and the two buckwheat honey treatments contained 0.79 +/- 0.02 and 1.71 +/- 0.21 mg of phenolic antioxidants per gram. Following consumption of the two honey treatments, plasma total-phenolic content increased (P < 0.05) as did plasma antioxidant and reducing capacities (P < 0.05). These data support the concept that phenolic antioxidants from processed honey are bioavailable, and that they increase antioxidant activity of plasma. It can be speculated that these compounds may augment defenses against oxidative stress and that they might be able to protect humans from oxidative stress. Given that the average sweetener intake by humans is estimated to be in excess of 70 kg per year, the substitution of honey in some foods for traditional sweeteners could result in an enhanced antioxidant defense system in healthy adults.