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Indonesian vs. Bribri: Striking lexical similarities in two unrelated languages
(2021) Krohn, Haakon Stensrud
Despite the fact that Indonesian and Bribri belong to two different language families and are spoken on opposite sides of the world, their lexicons contain many words that are strikingly similar. In this paper I analyze the origin of three word pairs from these languages that not only sound similar, but also have almost exactly the same meaning: (1) Indonesian kulit and Bribri kuö ́lit ‘skin, hide, leather, crust, shell, bark, rind, peel’, (2) Indonesian kutu and Bribri kú̱ ‘louse’, and (3) Indonesian kupu-kupu and Bribri kua’kua ‘butterfly’. The intention is not to propose any genealogical link between the Austronesian and the Chibchan language families, but rather to show how phonological, morphological and semantic properties can converge in two unrelated languages and produce this kind of eye-catching similarities.
Duración vocálica en el español de la Gran Área Metropolitana de Costa Rica
(2019-03-26) Krohn, Haakon Stensrud
En este artículo se describe un análisis acústico de la duración vocálica en palabras españolas leídas por estudiantes universitarios hispanohablantes de la Gran Área Metropolitana de Costa Rica. Los resultados revelan tres factores en el contexto lingüístico que aumentan la duración de las vocales en palabras bisilábicas. En primer lugar, las vocales en la primera sílaba son más largas cuando son tónicas que cuando son átonas. Asimismo, las vocales en la primera sílaba son más largas cuando la sílaba es abierta que cuando es cerrada. Por último, las vocales acentuadas en sílaba cerrada son más largas cuando esta sílaba es la segunda de la palabra que cuando es la primera.
In vitro antiplasmodial activity of phospholipases A2 and a phospholipase homologue isolated from the venom of the snake Bothrops asper
(2012-12-14) Quintana Castillo, Juan Carlos; Vargas, Leidy Johana; Segura Latorre, César Hernando; Gutiérrez, José María; Alarcón Pérez, Juan Carlos
The antimicrobial and antiparasite activity of phospholipase A2 (PLA2) from snakes and bees has been extensively explored. We studied the antiplasmodial effect of the whole venom of the snake Bothrops asper and of two fractions purified by ion-exchange chromatography: one containing catalytically-active phospholipases A2 (PLA2) (fraction V) and another containing a PLA2 homologue devoid of enzymatic activity (fraction VI). The antiplasmodial effect was assessed on in vitro cultures of Plasmodium falciparum. The whole venom of B. asper, as well as its fractions V and VI, were active against the parasite at 0.13 ± 0.01 µg/mL, 1.42 ± 0.56 µg/mL and 22.89 ± 1.22 µg/mL, respectively. Differences in the cytotoxic activity on peripheral blood mononuclear cells between the whole venom and fractions V and VI were observed, fraction V showing higher toxicity than total venom and fraction VI. Regarding toxicity in mice, the whole venom showed the highest lethal effect in comparison to fractions V and VI. These results suggest that B. asper PLA2 and its homologue have antiplasmodial potential.
"Bad things come in small packages": Predicting venom-induced coagulopathy in Bothrops atrox bites using snake ontogenetic parameters
(2019-08-06) Contreras Bernal, Jorge Carlos; Ferreira Bisneto, Pedro; Tavares Pereira, João Pedro; Najibe dos Santos Ibiapina, Hiochelson; Santos Sarraff, Lybia Kássia; Monteiro-Júnior, Cláudio; da Silva Pereira, Handerson; Santos, Bruno; Mourão de Moura, Valeria; Silva de Oliveira, Sâmella; Guimarães de Lacerda, Marcus Vinicius; de Souza Sampaio, Vanderson; Kaefer, Igor Luis; Gutiérrez, José María; Bernarde, Paulo Sérgio; Fan, Hui Wen; de Almeida Gonçalves Sachett, Jacqueline; Moura da Silva, Ana Maria; Monteiro, Wuelton Marcelo
Introduction: Snake venom composition shows significant inter- and intra-species variation. In the case of the viperid species Bothrops atrox, responsible for the majority of snakebites in the Amazon region, geographical and ontogenetic variables affect venom composition, with ecological and medical implications. Previous studies had shown that venom from neonate and juvenile Bothrops specimens have a higher in vitro coagulant activity. The aim of this investigation was to assess the association of clinical outcomes, such as venom-induced coagulopathy and local complications, with B. atrox ontogenetic variables. Methods: This study explored the relationship between some clinical parameters in patients suffering envenomations by B. atrox in the Amazon and several morphometric parameters of the snake specimens causing the bites. Results: There were 248 specimens confirmed as agents of envenomation, mostly female snakes (70.5%) and classified as juveniles (62.7%). Patients bitten by neonates compared to adult snakes [OR = 2.70 (95%CI 1.15-6.37); p = .021] and by snakes with white tail tip [OR = 1.98 (95%CI 1.15–3.41); p = .013] were more likely to develop coagulopathy. Time from patient admission to the unclottable blood reversion was not affected by the snake gender (p = .214) or age (p = .254). Patients bitten by neonate (p = .024) or juvenile snakes (p < .0001) presented a lower frequency of moderate to severe edema, as compared to those bitten by adult snakes. In agreement with experimental observations, patients bitten by neonates and by snakes with a white tail tip were more likely to develop coagulopathy than those bitten by adult snakes. In contrast, envenomations by adult snakes were associated with a higher incidence of severe local edema. Conclusion: Despite these variations, no difference was observed in the time needed to recover blood clotting in these patients after Bothrops antivenom administration.
Climate change-related distributional range shifts of venomous snakes: a predictive modelling study of effects on public health and biodiversity
(2024-03-05) Martinez, Pablo Ariel; Barbosa da Fonseca Teixeira, Irene; Siqueira Silva, Tuany; Barbosa da Silva, Franciely Fernanda; Gonzaga Lima, Luiz Antônio; Chaves Silveira, Jonatas; Olalla Tárraga, Miguel Ángel; Gutiérrez, José María; Ferreira Amado, Talita
Background. Climate change is expected to have profound effects on the distribution of venomous snake species, including reductions in biodiversity and changes in patterns of envenomation of humans and domestic animals. We estimated the effect of future climate change on the distribution of venomous snake species and potential knock-on effects on biodiversity and public health. Methods. We built species distribution models based on the geographical distribution of 209 medically relevant venomous snake species (WHO categories 1 and 2) and present climatic variables, and used these models to project the potential distribution of species in 2070. We incorporated different future climatic scenarios into the model, which we used to estimate the loss and gain of areas potentially suitable for each species. We also assessed which countries were likely to gain new species in the future as a result of species crossing national borders. We integrated the species distribution models with different socioeconomic scenarios to estimate which countries would become more vulnerable to snakebites in 2070. Findings. Our results suggest that substantial losses of potentially suitable areas for the survival of most venomous snake species will occur by 2070. However, some species of high risk to public health could gain climatically suitable areas for habitation. Countries such as Niger, Namibia, China, Nepal, and Myanmar could potentially gain several venomous snake species from neighbouring countries. Furthermore, the combination of an increase in climatically suitable areas and socioeconomic factors (including low-income and high rural populations) means that southeast Asia and Africa (and countries including Uganda, Kenya, Bangladesh, India, and Thailand in particular) could have increased vulnerability to snakebites in the future, with potential effects on public human and veterinary health. Interpretation. Loss of venomous snake biodiversity in low-income countries will affect ecosystem functioning and result in the loss of valuable genetic resources. Additionally, climate change will create new challenges to public health in several low-income countries, particularly in southeast Asia and Africa. The international community needs to increase its efforts to counter the effects of climate change in the coming decades.