Search

Parasites impact wildlife populations and ecosystem health, thereby demanding regular monitoring. As part of the national conservation effort to preserve the free-ranging sirenians in Colombia, a parasitological survey was conducted between 2011 and 2023 on naturally deceased Antillean manatees (Trichechus manatus manatus). A total of 17 stranded carcasses were analysed for the occurrence of parasites. Herein, trematode adult stages were recovered from the stomach, small intestine, caecum and colon of an adult male manatee and microscopically analysed. Additionally, molecular analysis was conducted based on an almost complete coding sequence of the ITS1-5.8S-ITS2, partial sequence of 18S and 28S ribosomal DNA (rDNA) genes. Phylogenetic analysis clustered the trematode sequences within Chiorchis fabaceus species, thus constituting the first adult-based sequences isolated for the species. Presented data contribute to a better understanding of the sirenian parasite diversity., Competing Interests: Declaration of competing interest None., (Copyright © 2024. Published by Elsevier B.V.)

Plasticized starch (PLS) nanocomposite films using glycerol and reinforced with graphene (G) and graphene oxide (GO) were prepared by solvent casting procedure. On one hand, the influence of adding different G contents into the PLS matrix was analyzed. In order to improve the stability of G nanoflakes in water, Salvia extracts were added as surfactants. The resulting nanocomposites presented improved mechanical properties. A maximum increase of 287 % in Young's modulus and 57 % in tensile strength was achieved for nanocomposites with 5 wt% of G. However, it seemed that Salvia acted as co-plasticizer for the PLS. Moreover, the addition of the highest G content led to an improvement of the electrical conductivity close to 5 × 10 -6 S/m compared to the matrix. On the other hand, GO was also incorporated as nanofiller to prepare nanocomposites. Thus, the effect of increasing the GO content in the final behavior of the PLS nanocomposites was evaluated. The characterization of GO containing PLS nanocomposites showed that strong starch/GO interactions and a good dispersion of the nanofiller were achieved. Moreover, the acidic treatment applied for the reduction of the GO was found to be effective, since the electrical conductivity was 150 times bigger than its G containing counterpart., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

According to the last leishmaniasis report from the Pan American Health Organization (2021) so far Panama is considered free of visceral leishmaniasis (VL). Although the presence of potential vectors and reservoirs involved in the VL transmission cycle have been described in some rural regions of the country, no cases have been reported in humans and domestic or wild animals. Dogs play an important role in the urban transmission of VL; therefore, it is important to detect possible cases of canine visceral leishmaniasis (CVL) in the country. In this sense,this study reports for the first time the Leishmania (Leishmania) infantum infection in imported dogs in Panama. Eleven dogs with clinical suspicion of CVL were evaluated by parasitological (bone marrow aspirate smear), serological (indirect immunofluorescence and/or reference immunochromatographic rapid test) and molecular tests (conventional PCR). The dogs included in this study were analyzed during the period from 2013 to 2020. All dogs presented clinical manifestations compatible with CVL. The samples were initially evaluated by smears and/or rapid serological tests by private practice veterinarians, and later confirmed by serological and/or molecular tests at the national reference laboratory for Leishmania diagnosis. The diagnosis was confirmed in 5/11 dogs by serological, parasitological and/or conventionals PCR targeting kDNA minicircle and Hsp70 gene. Leishmania (L.) infantum species was identified in 3/5 dogs by PCR-RFLP and by sequencing Hsp70-PCR products. This study evidenced the need to increase awareness of private practitioners as well as public health veterinarians on visceral leishmaniasis (VL), and to consider this parasitosis in the differential diagnosis of dogs with clinical and epidemiological characteristics compatible with the disease., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Biomass burning (BB) emissions significantly deteriorate air quality in many regions worldwide, impact human health and perturbing Earth's radiation budget and climate. South America is one of largest contributors to BB emissions globally. After Amazonia, BB emissions from open and agricultural fires of Northern South America (NSA) are the most significant. Recent evidence shows a strong correlation between fire counts in NSA and Brown Carbon in some Colombian cities, suggesting a substantial seasonal contribution of regional BB sources to air pollution levels in the densely populated areas of NSA. In this work we use the atmospheric regional chemical transport model WRF-Chem to assess the contribution of open BB events to pollutant concentration and to estimate potential health impacts associated with wildfire events in NSA. Three nested domains are used to simulate atmospheric composition in the Northern part of South America and the Caribbean. Simulations included biogenic and anthropogenic emissions from a global emission inventory merged with local emissions for the city of Bogotá. Two modelling scenarios were considered, a base case without BB emissions (NO_FIRE) and a sensitivity scenario with BB emissions. Simulations were carried out for periods of strong BB activity in NSA. In the NO_FIRE scenario, aerosol concentrations are unrealistically low. When BB emissions are is included background PM 2.5 concentrations increase 80%. The increment in aerosol concentrations is mainly driven by Secondary Organic Aerosols. In the case of Bogotá, the most densely populated city in the domain, monthly mean increase in PM 2.5 is 3.3 μg m -3 and 4.3 ppb for O 3 . Modeled meteorological and air pollution fields are in better agreement with observations when high spatial resolution (3 × 3 km) is used in the simulations. The total estimated short-term all-cause mortality associated to BB during February in the region is 171 cases, 88 PM 2.5 -related and 83 O 3 -related mortality., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Starch-based nanocomposite hydrogels were successfully prepared by the Diels-Alder click cross-linking reaction between furan-functionalized starch derivative and a water-soluble tetrafunctional maleimide compound, adding cellulose nanocrystals (CNC) as nanoreinforcement. The effect of increasing the CNC content on rheological and swelling properties as well as on the morphology of the hydrogels was analyzed. Besides, in order to evaluate the applicability of the as-prepared hydrogels as delivery systems, drug release measurements and in vitro cytotoxicity assays were also performed. It was found that the prepared nanocomposite hydrogels presented higher stiffness as the CNC content increased. The incorporation of the nanocrystals modified the internal porous microstructure of the hydrogels, affecting consequently both the swelling capacity and the drug-delivery kinetics. Moreover, the prepared nanocomposite hydrogels showed non-toxic behavior, demonstrating their potential applicability in the biomedical field, especially as sustained drug delivery systems., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Objective: Self-administered non-invasive therapies with high-fluoride dentifrices are an attractive alternative to traditional restorative management of root carious lesions (RCLs), but the available evidence is still scarce, particularly in community-dwelling elders. The aim of this randomized controlled trial (RCT) was to compare the effectiveness of toothbrushing with 5,000 ppm versus 1,450 ppm fluoridated dentifrice (F- dentifrice) on preventing and arresting RCLs, in community-dwelling elders., Methods: A two years double-blinded RCT was carried out with 345 independently-living older adults, with at least one tooth with RCL. Participants were instructed to brush twice per day with either high-fluoride (5,000 ppm F) or the control dentifrice (1,450 ppm F). Incidence of new and arrested existing RCLs was recorded at two years and compared with the baseline data. Linear mixed regression model with repeated measures were used to test differences between groups (p < 0.05)., Results: The percentage of teeth with active lesions varied significantly at two years, but in opposite directions for both groups. While the control group significantly increased the mean percentage of RCLs activity from baseline to two years, from 24.32% to 40.52%, the intervention decreased the percentage of activity from 29.74% to 3.72%. The incidence of RCL was 93.5% and 35.2% in participants of the 1,450 ppm and 5,000 ppm in the F- dentifrice groups, respectively, with a relative risk (RR) of 0.10 [CI: 0.05 - 0.19]., Conclusion: Non-invasive treatment with 5,000 ppm F dentifrice is more effective than conventional dentifrices in preventing and arresting RCLs in community dwelling elders. ClinicalTrials.gov NCT02647203., Clinical Significance: RCLs can be effectively prevented and arrested with the use of 5,000 ppm F dentifrice. Oral health programs directed to community-dwelling older adults might benefit from the inclusion of high fluoride dentifrice in their portfolio., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Pesticide intoxication is a major public health concern, and unfortunately there is not an effective treatment for severe organophosphorus pesticide intoxication. In this work, a non-immunogenic enzymatic bioconjugate based on cytochrome P450 was assayed for organophosphorus pesticide transformation. Enzyme therapy is an alternative approach to inactivate pesticides in the bloodstream, transforming them into less toxic metabolites. A variant of cytochrome P450 (CYP BM3 F87A) from Bacillus megaterium was chemically modified with polyethylene glycol. The PEGylated enzyme showed enhanced pesticide transformation activity when compared with the unmodified protein. The transformation rates were higher than those obtained with the unmodified enzyme for all six pesticides transformed. The specific activity of PEGylated preparation for parathion and dichlorophen was up to 9-times higher than these obtained with the unmodified enzyme. In addition, the modified CYP (CYP-PEG) remained active at extremely high pHs, maintaining 90% of its maximal activity at pH 11, as opposed to the unmodified CYP that retained less than 20% of its maximal activity at that pH. In addition, the bioconjugate showed good catalytic activity in blood serum and innocuousness on immune cells. The potential use of PEGylated CYP as a detoxification strategy for pesticide poisoning is demonstrated and discussed., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The Caribbean mollusc Dolabrifera dolabrifera from Puerto Rico contains two new propionate-derived metabolites, dolabriferol B and C (2 and 3), in addition to the known compound dolabriferol (1). The structures of dolabriferol B (2) and C (3) were established by comparison of their spectral data with those of 1, and the absolute configuration of 2 was determined from chemical degradation studies. The structure of dolabriferol C (3) was confirmed by X-ray analysis.

The addition of milk and milk-based products to the diets of individuals subsisting on plant-based diets was reported to have positive effects on nutritional status and functional outcomes such as growth, morbidity, and cognition. We examined the effect of the addition of milk or yogurt on the bioavailability of zinc and iron from a plant-based rural diet. The subjects were 48 Mexican women (30.9 +/- 5.7 y) who habitually consumed a plant-based diet. The women were assigned to 1 of 3 groups: 1) the typical rural Mexican diet, 2) that diet with milk added, or 3) that diet with yogurt for 13 d. Zinc absorption was measured after extrinsically labeling meals with (67)Zn and an i.v. dose of (70)Zn; iron absorption was measured by extrinsically labeling meals with (58)Fe and a reference oral dose of (57)Fe. Including milk and yogurt in the diet increased zinc absorption by 50 and 68%, respectively (P < 0.05). The 3 groups did not differ in the percentage iron absorption. The total amount of zinc absorbed was increased (P < 0.05) by 70% when milk was added to the meal and 78% when yogurt was added. The total amount of iron absorbed did not differ among the groups. The addition of milk and yogurt to a plant-based diet high in phytate increases zinc bioavailability without affecting iron bioavailability.