Case report on postmortem fentanyl measurement after overdose with more than 67 fentanyl patches

PURPOSE: Fentanyl is an analgesic that is frequently prescribed, which resulted in non-intentional as well as intentional misuse and deaths. Here, we present a postmortem case of a patient who clearly died of a fentanyl overdose due to an extensive number of fentanyl patches combined with oral intake of fentanyl and cocaine. We aimed to show how postmortem analysis can be used to interpret postmortem fentanyl concentrations in unique cases like the one we present. CASE DESCRIPTION: A 23-year-old male was found dead in his bedroom with 67 non-prescribed patches of fentanyl on his body. In the room, there also were fentanyl tablets of 100 µg and cocaine powder, which had possibly also been taken by the deceased. To confirm the cause of death, urine and subclavian blood were retrieved to perform a standard postmortem toxicology screening. The toxicological screening revealed the presence of several drugs, including cocaine, fentanyl, lidocaine and paracetamol. Further analysis of the quantitative postmortem values of fentanyl with ultra-performance liquid chromatography-tandem mass spectrometry revealed a fentanyl concentration of 57.9 µg/L. Considering several issues around postmortem drug analyses, this value seemed to be in line with concentrations found in previously reported postmortem cases. CONCLUSION: We were able to confirm the expected cause of death with an extensive toxicological screening in combination with the circumstantial evidence. We identified fentanyl as most important cause for the fatal outcome in this specific case and simultaneously contributed to the limited availability of knowledge on postmortem fentanyl concentrations

Lianas and their supporting plants in the understorey at Los Tuxtlas, Mexico

Lianas are woody climbing plants that begin their life cycles as seedlings rooted in the ground, but eventually rely on other plants for physical support in order to reach the top of the forest canopy (Holbrook & Putz 1996, Putz & Holbrook 1991). Lianas can negatively affect plants they climb by competing with them for common resources such as light, water and nutrients, and by causing them direct physical damage (Dillenburg et al. 1995, Pérez-Salicrup & Barker 2000, Stevens 1987, Whigham 1984). Yet, there is little documentation about the size at which liana individuals of different species begin to climb on other plants in nature. This information is important because the size at which a liana begins to climb on other plants will determine when lianas potentially start physically affecting their supporting plants. Furthermore, although the growth of liana seedlings might be determined by light (Sanches & Válio 2002), the availability of support will also largely influence the rate of growth of liana stems (Peñalosa 1982, 1983, 1985). Thus, information about the size at which liana species find support in the forest understorey will be useful in understanding future growth of liana individuals

Positive effect of surrounding rainforest on composition, diversity and late-successional seed dispersal by bats

The configuration of a heterogeneous landscape has an important effect on species composition and landscape processes. The importance of the size, shape and habitat suitability of forest patches has been widely studied, but there is increasing evidence that the spatial context, e.g. adjacency or contact between two landscape elements, can have positive effects on ecological interactions, such as the movement of frugivorous bat species and seed dispersal. We compared the composition, diversity and richness of seed species transported by bats in rainforests and in secondary forests that were either partially or largely surrounded by rainforest, in relation to the fruit species’ life form and successional stage. To capture frugivorous bats we used mist nets with a plastic sheet placed below to allow dropped fruit and seeds from bat feces to be retrieved. Similar species composition and the highest diversity of transported seeds were found in rainforest and secondary forest largely surrounded by rainforest, while the highest number of seed species was recorded in rainforest and secondary forest partially surrounded by rainforest. More bats were captured transporting late successional stage seeds in secondary forest largely surrounded by rainforest. This study demonstrates the importance of rainforest surrounding secondary forests to bat species’ movement and its positive effect on diversity and late successional seed dispersal by bats. Maintaining large areas of rainforest around secondary forests is a useful management strategy for supporting high bat species diversity and abundance, and positively affects the transportation and potential dispersal of seed species of different successional stages

Tropical rain-forest matrix quality affects bat assemblage structure in secondary forest patches

We studied Phyllostomidae bat assemblage structure in patches of secondary forest dominated by the pioneer tree Ochroma pyramidale, largely (.85%) or partially (,35%) surrounded by a matrix of tropical rain forest, to test 3 hypotheses: the highest bat diversity and richness is observed in the matrix rain forest in comparison to secondary forest patches; the proportion of rain forest surrounding secondary forest positively affects bat diversity and richness; and canopy openness is an important structural variable negatively affecting bat abundance. Rain-forest control sites had the highest bat species diversity and richness, and contributed more to total diversity than did secondary forest. Bat diversity was similar between secondary forest patches largely enclosed by rain forest and their controls, but higher diversity, richness, and contribution to total diversity were recorded in largely enclosed patches compared to partially enclosed patches. Partially enclosed patches were dominated by 2 small, frugivorous understory bat species (Carollia sowelli and Carollia perspicillata), whereas largely enclosed patches were dominated by 2 large-bodied, canopy-dwelling, frugivorous bats (Artibeus lituratus and Artibeus jamaicensis), which primarily feed on figs, a tree species that is abundant in rain forest. Bat diversity, richness, and contribution to total diversity were positively correlated with the proportion of area with rain forest, and bat abundance was negatively correlated with canopy openness

Can a fast­growing early­successional tree (Ochroma pyramidale, Malvaceae) accelerate forest succession?

Species-specific traits of trees affect ecosystem dynamics, defining forest structure and understorey development. Ochroma pyramidale is a fast-growing tree species, with life-history traits that include low wood density, short-lived large leaves and a narrow open thin crown. We evaluated forest succession in O. pyramidale-dominated secondary forests, diverse secondary forests, both 10–15 y since abandonment, and rain forests by comparing height, density and basal area of all trees (> 5 cm dbh). Furthermore, we compared species richness of understorey trees and shrubs, and basal area and density of trees of early- and late-successional species ( 15%) and leaf litter (> 10 cm) were both highest in O. pyramidale forests, which positively affected density of understorey trees and shrubs and negatively affected density of late-successional trees. In conclusion, O. pyramidale forests presented structural features similar to those of rain forest, but this constrained the establishment of understorey tree species, especially late-successional species, decreasing successional developmen

Positive effect of surrounding rainforest on composition, diversity and late-successional seed dispersal by bats

The configuration of a heterogeneous landscape has an important effect on species composition and landscape processes. The importance of the size, shape and habitat suitability of forest patches has been widely studied, but there is increasing evidence that the spatial context, e.g. adjacency or contact between two landscape elements, can have positive effects on ecological interactions, such as the movement of frugivorous bat species and seed dispersal. We compared the composition, diversity and richness of seed species transported by bats in rainforests and in secondary forests that were either partially or largely surrounded by rainforest, in relation to the fruit species’ life form and successional stage. To capture frugivorous bats we used mist nets with a plastic sheet placed below to allow dropped fruit and seeds from bat feces to be retrieved. Similar species composition and the highest diversity of transported seeds were found in rainforest and secondary forest largely surrounded by rainforest, while the highest number of seed species was recorded in rainforest and secondary forest partially surrounded by rainforest. More bats were captured transporting late successional stage seeds in secondary forest largely surrounded by rainforest. This study demonstrates the importance of rainforest surrounding secondary forests to bat species’ movement and its positive effect on diversity and late successional seed dispersal by bats. Maintaining large areas of rainforest around secondary forests is a useful management strategy for supporting high bat species diversity and abundance, and positively affects the transportation and potential dispersal of seed species of different successional stages

Niche differentiation and its relationship with food abundance and vegetation complexity in four frugivorous bat species in southern Mexico

Species can co-exist within a community when their use of limiting resources is differentiated. To test whether differentiation facilitates coexistence, we quantified differences and overlap in habitat use, fruit consumption, morphological characteristics, and the relationship with vegetation structure for two pairs of ecologically similar frugivorous bat species, Carollia sowelli and C. perspicillata, and Artibeus jamaicensis and A. lituratus. In Carollia sowelli and C. perspicillata, differences in body mass and wing aspect ratio were not reflected in differences in fruit or habitat use (diet overlap, 96 percent; habitat overlap, 98 percent). However, the capture rate of Carollia sowelli positively correlated with canopy openness, and that of C. perspicillata positively correlated with tree height. Body mass and wing characteristics of Artibeus species suggested a greater maneuverability for A. jamaicensis. Also, more A. jamaicensis individuals were captured feeding on Ficus spp., while Artibeus lituratus preferred fruits of the early successional tree Cecropia. However, both habitat overlap and diet overlap were higher than by chance (diet overlap, 75 percent; habitat overlap, 92 percent). The co-existence of the four bat species in the study area may be facilitated by the abundance of the food resources forming part of the diets of both Carollia species, by the morphological differences between the Artibeus species, which allow the differentiation of foraging behavior in relation to fruit consumption, and by the structural characteristics of the vegetation

Deforestation Impacts on Bat Functional Diversity in Tropical Landscapes

<div><p>Functional diversity is the variability in the functional roles carried out by species within ecosystems. Changes in the environment can affect this component of biodiversity and can, in turn, affect different processes, including some ecosystem services. This study aimed to determine the effect of forest loss on species richness, abundance and functional diversity of Neotropical bats. To this end, we identified six landscapes with increasing loss of forest cover in the Huasteca region of the state of Hidalgo, Mexico. We captured bats in each landscape using mist nets, and calculated functional diversity indices (functional richness and functional evenness) along with species richness and abundance. We analyzed these measures in terms of percent forest cover. We captured 906 bats (Phyllostomidae and Mormoopidae), including 10 genera and 12 species. Species richness, abundance and functional richness per night are positively related with forest cover. Generalized linear models show that species richness, abundance and functional richness per night are significantly related with forest cover, while seasonality had an effect on abundance and functional richness. Neither forest cover nor season had a significant effect on functional evenness. All these findings were consistent across three spatial scales (1, 3 and 5 km radius around sampling sites). The decrease in species, abundance and functional richness of bats with forest loss may have implications for the ecological processes they carry out such as seed dispersal, pollination and insect predation, among others.</p></div