Histopathological changes in the gills and liver of Prochilodus lineatus from the Salado River basin (Santa Fe, Argentina)

This study evaluated the histopathological changes in gills and liver of Prochilodus lineatus inhabiting the Salado River basin. Fish were collected in four different sampling stations. The histological lesions in the tissues were examined under light microscopy and evaluated with quantitative analyses. The morphometric analysis of the gills showed a significant shortening of secondary lamellae and a lower percentage of area for gas exchange in fish from station 1 (an urban area, located near the mouth of the Salado River) in comparison with fish gills from the reference site (station 4, a relatively pristine area). Moreover, a significantly higher area occupied with necrotic foci and the occurrence of an important inflammatory response were observed in fish liver of station 1 than the samples caught from other stations. Thus, histopathological evidences showed differences among sites, which could be related to different environmental conditions.     

Individual leaf area estimations of a dioecious tropical tree species <Emphasis Type="Italic">Carpotroche brasiliensis</Emphasis> (Raddi) A. Gray,Achariaceae

Carpotroche brasiliensis is a dioecious tree species native of the Brazilian Atlantic rainforest. Due to medical and industrial use of the oil extracted from its seeds, C. brasiliensis has a great potential for cultivation as non-timber forest product in agroforestry systems. This study was conducted with the objective to analyze the leaf dimensions of male and female adult trees and seedlings of C. brasiliensis. Two hypotheses were tested: (a) leaf dimensions do not differ between male and female adult genotypes; and (b) it is possible to develop single regression models for predicting leaf area (LA) from dimensional variables encompassing male and female adult genotypes and seedlings. LA, leaf length (L) and maximum leaf width (W) were measured in leaves collected from seven male and seven female adult genotypes and three seedling lots. The feasibility of using a single model for leaves of males and females, and seedlings and adults, was tested by analysis of covariance (ANCOVA). The prediction errors (PE) for each of the regression models were calculated from the cross-validation method. The average values of L, W and LA were, respectively, 136, 142 and 457 % higher in adults than in seedlings, and the average values of leaf shapes (L:W) of seedlings were intermediate between the average values of L:W of adult males and females. The average values of L did not differ between adult males and females, but significant differences were observed between males and females for W, LA and L:W (both p < 0.01, nested ANOVA). The mean L:W values of adult males and females, and seedlings, indicate that leaf shape should be used as a criterion for sex differentiation in this species. It was not possible to develop single models encompassing adult males and females, and seedlings; but high accurate predictive models of LA from L × W measurements were developed for adult males (R² = 0.98, PE = 0.69, n = 350), adult females (R² = 0.98, PE = 0.01, n = 350), and seedlings (R² = 0.99, PE = 6.80, n = 150).     

Recreational Multifunctionality and its implications for agroforestry diffusion

Recreational Multifunctionality refers to those farms providing at least one recreational service to members of the farm household or the public. Based on the types of recreational services offered, two types of landowners have been identified: Productivists and Ruralists. They differ on their extent of Recreational Multifunctionality, farm household attributes and farm representation. Both types of landowners also have different behavior and understanding of agroforestry. This study builds on the Recreational Multifunctionality construct to identify message content, channels and agencies that can better facilitate the diffusion of agroforestry. In 2006, 353 randomly selected landowners from Missouri were interviewed and clustered in two groups: Productivists (38.0%) and Ruralists (62.0%). These groups were examined to identify differences regarding their perceptions of being a good farmer (i.e., message content); their preferred source of information (i.e., communication channel); and their preferred agencies for learning purposes (i.e., communication agencies). Study results show differences between Productivists and Ruralists in all three aspects of diffusion examined (i.e., message content, channels and agencies), suggesting that all landowners should not be approached in the same way when promoting agroforestry. Messages conveyed to Productivists should emphasize the economic benefits of agroforestry, while messages to Ruralists should emphasize the conservation benefits of agroforestry. Touring farms with active tree management is a good way to disseminate agroforestry practices among Productivists while state and federal extension agents appear to be more suitable to approach Ruralists. Both groups can effectively be reached using printed materials, especially through official conservation magazines.     

Redox Stratification and Salinization of Three Kettle Lakes in Southwest Michigan,USA

Redox stratification, especially hypolimnetic anoxia resulting from eutrophication, and salinization resulting from application of salts for road deicing is investigated in three kettle lakes in southwest Michigan. Two of the lakes (Asylum and Woods Lakes) are located in urban Kalamazoo, Michigan, and the third (Brewster Lake) is located in rural Hastings, Michigan. In summer, the water columns of all three lakes are distinctly redox stratified, with anoxic hypolimnia and significant accumulation of reduced solutes (e.g., Mn(II), Fe(II), ammonia) in the lake bottom waters. Extremely elevated conductivity, chloride, sodium, and potassium levels are observed in the urban Asylum and Woods Lakes compared to the rural Brewster Lake, presumably due to runoff of road salt deicers applied in the surrounding watershed. These significant changes in water quality are of concern because they may detrimentally impact lake mixing, biodiversity, and ecosystem function in the urban lakes.     

Domestication of Alpine blue-sow-thistle (<Emphasis Type="Italic">Cicerbita alpina</Emphasis> (L.) Wallr.): six year trial results

Alpine blue-sow-thistle (Cicerbita alpina (L.) Wallr.) is a perennial herb distributed all along the entire Alpine Arc, the shoots of which are still collected in the wild in several areas of Northern-Eastern Italy for food purposes. Our paper deals with experiments of domestication of this species carried out in the surroundings of Trento and lasted from 2004 to 2010. The cultivation was carried out transplanting seedlings, obtained by wild seed of a unique accession. One experimental trial (2004/2008) was carried in the location Frisanchi, located at 1,078 m a.s.l. In this trial the theses compared 4 harvests, 1 week spaced, carried out respectively in the 2nd, 3rd and 4th year after the transplant. Of the total quantity harvested after 4 years, the most shoots (60) and the highest dried weight per m² (14 g) were obtained from shoots collected 2 or 3 years after being transplanted. However, comparing the shoots yielded in the last year of the trial only (2008), the best results were obtained from 3 or 4-year-old transplants (42 shoots/m²; 8.2 g dry weight). Nevertheless there four times harvesting of shoots weakened the plants’ development and a high failure rates was recorded. In addition to the real experimental trial another small cultivation was carried out in an higher location, Monte Bondone at 1,500 m a.s.l., in which 5 years after the transplant (2010) only 2 harvests were carried out. In this experiment the yield recorded was very encouraging (10.5 g m²) and also the quality of the shoots collected was good.     

Association of Trypanosoma vivax in extracellular sites with central nervous system lesions and changes in cerebrospinal fluid in experimentally infected goats

ABSTRACT: Changes in cerebrospinal fluid (CSF) and anatomical and histopathological central nervous system (CNS) lesions were evaluated, and the presence of Trypanosoma vivax in CNS tissues was investigated through PCR. Twelve adult male goats were divided into three groups (G): G1, infected with T. vivax and evaluated during the acute phase; G2, infected goats evaluated during the chronic phase; and G3, consisting of non-infected goats. Each goat from G1 and G2 was infected with 1.25 × 105 trypomastigotes. Cerebrospinal fluid (CSF) analysis and investigation of T. vivax was performed at the 15th day post-infection (dpi) in G1 goats and on the fifth day after the manifestation of nervous system infection signs in G2 goats. All goats were necropsied, and CNS fragments from G1 and G2 goats were evaluated by PCR for the determination of T. vivax. Hyperthermia, anemia and parasitemia were observed from the fifth dpi for G1 and G2, with the highest parasitemia peak between the seventh and 21st dpi. Nervous system infection signs were observed in three G2 goats between the 30th and 35th dpi. CSF analysis revealed the presence of T. vivax for G2. Meningitis and meningoencephalitis were diagnosed in G2. PCR were positive for T. vivax in all the samples tested. In conclusion, T. vivax may reach the nervous tissue resulting in immune response from the host, which is the cause of progressive clinical and pathological manifestations of the CNS in experimentally infected goats.     

Prior and concomitant dehydroepiandrosterone treatment affects immunologic response of cultured macrophages infected with Trypanosoma cruzi in vitro?

DHEA, a steroid hormone synthesized from cholesterol by cells of the adrenal cortex, plays an essential role in enhancing the host's resistance to different experimental infections. Receptors for this hormone can be found in distinct immune cells (especially macrophages) that are known to be the first line defense against Trypanosoma cruzi infection. These cells operate through an indirect pathway releasing nitric oxide (NO) and cytokines such TNF-α and IL-12 which in turn trigger an enhancement of natural killer cells and lymphocytes which finally secrete pro and anti-inflammatory cytokines. The effects of pre- and post-infection DHEA treatment on production of IL-12, TNFα and NO were evaluated. T. cruzi infected macrophages post treated with DHEA displayed enhanced concentrations of TNF-α, IL-12 and NO. Probably, the mechanisms that induced the production of cytokines by infected cells are more efficient when the immune system has been stimulated first by parasite invasion, suggesting that the protective role of DHEA is greater when administered post infection.     

Responses of Biochemical Markers in the Fish Prochilodus lineatus Exposed to a Commercial Formulation of Endosulfan

Among the most extensively used compounds for the pest control in Argentinean crops is the organochlorine endosulfan. The sublethal effects of the commercial endosulfan formulation on hematology and lipid peroxidation (LPO) of the neotropical fish Prochilodus lineatus were investigated. Firstly, we calculated acute toxicity (LC₅₀) in order to define sublethal concentrations (0, 1.2, and 2.4 ??g L^?1). Hematological and oxidative stress responses were assessed at 24, 48, and 96 h. Endosulfan exposure significantly diminished the hemoglobin concentration, mean cell hemoglobin, and total plasma protein and increased white blood cells count and plasma glucose after 96 h. Exposed fish showed an alteration of the differential leukocytes count, evidenced by more thrombocytes and monocytes and less lymphocytes and neutrophils. Endosulfan increased LPO levels in intestine, liver, and brain in both sublethal concentrations. The present results suggest that endosulfan produces biochemical and physiological alterations, including immunological disorders, and it is a good inductor of oxidative stress in P. lineatus.     

Ocular and periocular radiation toxicity in dogs treated for sinonasal tumors: A critical review

Visual impairment from radiation‐induced damage can be painful, disabling, and reduces the patient's quality of life. Ocular tissue damage can result from the proximity of ocular organs at risk to irradiated sinonasal target volumes. As toxicity depends on the radiation dose delivered to a certain volume, dose‐volume constraints for organs at risk should ideally be known during treatment planning in order to reduce toxicity. Herein, we summarize published ocular toxicity data of dogs irradiated for sinonasal tumors from 36 publications (1976‐2018). In particular, we tried to extract a dose guideline for a clinically acceptable rate of ocular toxicity. The side effects to ocular and periocular tissues were reported in 26/36 studies (72%) and graded according to scoring systems (10/26; 39%). With most scoring systems, however, toxicities of different ocular and periocular tissues are summed into one score. Further, the scores were mostly applied in retrospect and lack volume‐ and dose‐data. This incomplete information reflects the crux of the matter for radiation dose tolerance in canine ocular tissues: The published information of the last three decades does not allow formulating dose‐volume guidelines. As a start, we can only state that a mean dose of 39 Gy (given in 10 x 4.2 Gy fractions) will lead to loss of vision by one or both eyes, while mean doses of <30 Gy seem to preserve functionality. With a future goal to define tolerated doses and volumes of ocular and periocular tissues at risk, we propose the use of combined ocular toxicity scoring systems.