-
Toxicon : Official Journal of the... Jun 2024Of the mycotoxicoses caused by molds contaminating grains or their byproducts, leukoencephalomalacia of horses and less frequently aflatoxicosis in cattle have been... (Review)
Review
Of the mycotoxicoses caused by molds contaminating grains or their byproducts, leukoencephalomalacia of horses and less frequently aflatoxicosis in cattle have been reported in South America. However, the most important group of mycotoxins in the region are those caused by fungi that infect forages and other types of plants and have regional distribution. In this group, ergotism is important, both caused by Claviceps purpurea infecting grains or by Epichloë coenophiala infecting Schedonorus arundinaceus. Other important mycotoxicoses are those caused by indole-diterpenes produced by Clavicipitaceous fungi including Claviceps paspali in Paspalum spp., Claviceps cynodontes in Cynodon dactylon, and by Periglandula a seed transmitted symbiont associated with the tremorgenic plant Ipomoea asarifolia. The latter is an important poisoning in the northeastern and northern Brazil. Other important mycotoxicoses are those caused by swainsonine containing plants. It was demonstrated that swainsonine contained in Ipomoea carnea var. fistulosa is produced by an epibiotic fungus of the order Chaetothyriales whose mycelia develop on the adaxial surface of the leaves. Swainsonine is also produced by the symbiotic, endobiotic fungi Alternaria section Undifilum spp., which is associated with Astragalus spp. in the Argentinian Patagonia causing poisoning. Another form of mycotoxicosis occurs in poisoning by Baccharis spp., mainly B. coridifolia, a very important toxic plant in South America that contains macrocyclic trichothecenes probably produced by an endophytic fungus that has not yet been identified. Pithomycotoxicosis caused by Pithomyces chartarum used to be an important mycotoxicosis in the region, mainly in cattle grazing improved pastures of legumes and grasses. Slaframine poisoning, diplodiosis and poisoning by barley contaminated by Aspergillus clavatus has been rarely diagnosed in Brazil, Uruguay and Argentina.
PubMed: 38909760
DOI: 10.1016/j.toxicon.2024.107827 -
Revista Alergia Mexico (Tecamachalco,... Feb 2024To identify and registry the most important aeroallergens trapped at the aerobiology station in the city of Samborondon, Ecuador.
OBJETIVO
To identify and registry the most important aeroallergens trapped at the aerobiology station in the city of Samborondon, Ecuador.
METHODS
Pollen grains and fungal spore counts were performed according to the standardized technique with a Hirst-type collection equipment, Burkard spore trap for seven days, following the recommendations of the National Allergy Bureau (NAB) of the American Academy of Allergy Asthma and Immunology (AAAAI). The equipment was installed on the roof of the Universidad de Especialidades Espiritu Santo (UEES), 25 m above ground level, coordinates: 2°07 ́57 ́ ́S 79°52 ́06 ́ ́W, in the city of Samborondon. The sampling period was performed from November 2022 to April 2023.
RESULTS
We identified the following pollen families: Poaceae (258 grains/m3), Apocynaceae (Plumeria rubra pc) (214 grains/m3), Lamiaceae (180 grains/m3), Asteraceae Ambrosía spp.- (60 grains/m3), Chenopodiacea (27 grains/m3), Myrtaceae (17 grains/m3), Pinaceae (11 grains/m3), Betulaceae (7 grains/m3). Also identified fungical spores: Fuzariella spp./Leptosphaeria spp. (1899/m3), Cladosporium spp. (1407/m3), Nigrospora spp. (1183/m3), Dreschlera/Helmintosporum spp. (329/m3), Alternaria spp. (98/m3), Pithomyces spp. (79/m3), Curvularia spp. (48/m3), Stemphylium spp. (46/m3).
CONCLUSIONS
We reported the first study of aerobiology (capture and identification of environmental pollens and fungi) in the city of Samborondon. The inhabitants of this area are exposed to different aeroallergens with a predominance of Poaceaes pollen and Fuzzariella spp./Leptosphaeria spp. spores. The identified allergens should be part of the usual allergy studies. The results of this first preliminary study should be compared with information from the forthcoming years, which will help to identify variations in the concentration of seasonal aeroallergens, annual fluctuations, and extend the traps to other parts of the city.
Topics: Ecuador; Pollen; Spores, Fungal; Allergens; Environmental Monitoring
PubMed: 38683070
DOI: 10.29262/ram.v71i1.1366 -
Marine Drugs Mar 2024, a common food-borne pathogen, forms biofilms and generates virulence factors through a quorum sensing (QS) mechanism. In this study, six compounds (dankasterone A,...
, a common food-borne pathogen, forms biofilms and generates virulence factors through a quorum sensing (QS) mechanism. In this study, six compounds (dankasterone A, demethylincisterol A, zinnimidine, cyclo-(L-Val-L-Pro), cyclo-(L-Ile-L-Pro), and cyclo-(L-Leu-L-Pro)) were isolated from the endophytic fungus of the sp. in the South China Sea. Among them, demethylincisterol A, a sterol derivative, exhibited strong QS inhibitory activity against . The QS inhibitory activity of demethylincisterol A was evaluated through experiments. The minimum inhibitory concentration (MIC) of demethylincisterol A against was 6.25 μg/mL. At sub-MIC concentrations, it significantly decreased biofilm formation, hindered mobility, and diminished the production of protease and hemolysin activity. Moreover, RT-qPCR results demonstrated that demethylincisterol A markedly inhibited the expression of QS-related genes ( and ) in . The exposure to demethylincisterol A3 resulted in the downregulation of genes (, , , , , , , and ) associated with biofilm formation, mobility, and virulence factors. Hence, demethylincisterol A is a potentially effective compound in the pipeline of innovative antimicrobial therapies.
Topics: Quorum Sensing; Bacillus cereus; Biofilms; Anti-Bacterial Agents; Microbial Sensitivity Tests; Laurencia; Virulence Factors; China; Endophytes
PubMed: 38667778
DOI: 10.3390/md22040161 -
Microbial Pathogenesis Dec 2023Facial eczema is often found in flocks of grazing sheep in China. To investigate fungi species those cause disease and pathological roles. Forage and soil samples were...
Facial eczema is often found in flocks of grazing sheep in China. To investigate fungi species those cause disease and pathological roles. Forage and soil samples were collected during the pathogenic season and cultured. Samples were collected from regions with and without facial eczema affected sheep. Fungal isolation and identification, statistical analysis of fungal species and distribution were performed. Pathological changes, biochemical parameters of serum liver function and protection of inflammatory factors that tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-12 (IL-12) were observed. Fungal cultivation and identification showed that separation rate of Alternaria, Pithomyces chartarum, Fusarium and Aspergillus were higher, particularly, Pithomyces chartarum was significantly identical. Pathological anatomy and histology indicated that the disease likely attacked merino ewes with the age of 6 months old. The clinical manifestations were characterized by inflammational edema in face (ears and eyelids) and mandibular area. Postmortem examination of dead lambs showed enlargement of liver with yellow white patchs of necrotic lesion and tuberous sclerosis and fibrosis on section. Histologic examination of liver showed extravasated blood, severe lesion of liver cells and bile duct, and fatty degeneration. In sheep, fungal toxin induced the secretion of TNF-α, IL-6 and IL-12. These results revealed that Pithomyces chartarum maybe caused facial eczema and inflammation in sheep. The facial eczema was allergic eczema caused by hepatic dysfunction and hepatonecrosis.
Topics: Sheep; Animals; Female; Interleukin-6; Tumor Necrosis Factor-alpha; Eczema; Inflammation; Ascomycota; Sheep, Domestic; Interleukin-12; Sheep Diseases
PubMed: 37981078
DOI: 10.1016/j.micpath.2023.106451 -
New Zealand Veterinary Journal Jan 2024To examine the relationship in dairy cattle between serum and faecal Zn concentrations and daily intake of Zn supplemented with an oral drench; and whether total daily...
AIMS
To examine the relationship in dairy cattle between serum and faecal Zn concentrations and daily intake of Zn supplemented with an oral drench; and whether total daily intake (TDI) of Zn in dairy cattle can be predicted from single measurements of Zn concentration in serum or faeces.
METHODS
A convenience sample of 20 animals from three stock classes (lactating cows, dry cows, heifers), that had not received Zn supplementation in the previous 60 days, was enrolled in the study. From Days -7 to -1, animals received no Zn supplementation. On Day 0, 15 animals per class were assigned daily drenching with increasing doses of ZnSO.7HO while five remained controls. From Days 0-6, treatment animals received 12.5 mg/kg LWT of Zn/day; from Days 7-13, 25 mg/kg LWT Zn/day and from Days 14-20, 37.5 mg/kg LWT Zn/day. Animals co-grazed within each stock class. Pasture, serum and faecal samples were collected at the start and at weekly intervals before each increase in Zn supplementation. Mixed and non-parametric models were used to assess treatment effects and whether daily intake of Zn could be predicted from Zn concentrations in serum and faeces.
RESULTS
Dosing with 0, 12.5, 25.0 and 37.5 mg Zn/kg LWT resulted in serum Zn concentrations of 12.1, 16.7, 27.2 and 35.8 µmol/L in heifers, 13.3, 17.1, 26.4 and 40.0 µmol/L in dry and 11.9, 12.1, 23.4 and 27.2 µmol/L in lactating cows. Dosing with the same amounts of Zn resulted in faecal Zn concentrations of 2.95, 21.72, 40.32 and 53.27 mmol/kg DM in heifers, 2.81, 23.77, 55.16 and 68.20 mmol/kg DM in dry and 3.00, 12.71, 34.86 and 57.53 mmol/kg DM in lactating cows, respectively. Treatment elevated serum and faecal Zn concentrations above controls (p < 0.001). Supplemented lactating cows had lower serum Zn concentrations than dry cows or heifers (p < 0.01). Supplemented dry cows had faecal DM Zn concentrations higher than heifers or lactating cows (p < 0.05). Analysis showed serum and faecal Zn concentrations could predict TDI of Zn (p < 0.001). Concentrations of Zn in faeces estimated TDI of Zn within a narrower predictive interval than serum Zn concentrations.
CONCLUSIONS AND CLINICAL RELEVANCE
Concentrations of Zn in serum and faeces were positively associated with TDI of Zn in dairy cattle and could predict TDI of Zn. When using serum and faecal Zn concentrations to estimate TDI Zn, stock class must be accounted for.
Topics: Animals; Cattle; Female; Zinc; Zinc Sulfate; Lactation; New Zealand; Dietary Supplements; Feces; Diet; Milk
PubMed: 37972406
DOI: 10.1080/00480169.2023.2269131