-
Genes Nov 2023The polymorphism of SINE-containing loci reflects the evolutionary processes that occurred both during the period before the divergence of the taxa and after it....
The polymorphism of SINE-containing loci reflects the evolutionary processes that occurred both during the period before the divergence of the taxa and after it. Orthologous loci containing SINE in two or more genomes indicate the relatedness of the taxa, while different copies may have a specific set of mutations and degree of difference. Polymorphic insertion can be interpreted with a high degree of confidence as a shared derived character in the phylogenetic reconstruction of the history of the taxon. The computational comparison of the entire set of SINE-containing loci between genomes is a challenging task, and we propose to consider it in detail using the genomes of representatives of squamate reptiles (lizards) as an example. Our approach allows us to extract copies of SINE from the genomes, find pairwise orthologous loci by using flanking genomic sequences, and analyze the resulting sets of loci for the presence or absence of SINE, the degree of similarity of the flanks, and the similarity of the SINE themselves. The workflow we propose allows us to efficiently extract and analyze orthologous SINE loci for the downstream analysis, as shown in our comparison of species- and genus-level taxa in lacertid lizards.
Topics: Animals; Phylogeny; Evolution, Molecular; Short Interspersed Nucleotide Elements; Genome; Lizards
PubMed: 38003031
DOI: 10.3390/genes14112089 -
PLoS Neglected Tropical Diseases Oct 2023Snakebite envenoming remains a public health threat in many tropical countries including Malawi. Traditional healers (THs) have been consulted by victims of snakebites...
Snakebite envenoming remains a public health threat in many tropical countries including Malawi. Traditional healers (THs) have been consulted by victims of snakebites as primary caregivers for millennia. There are no studies in Malawi to understand this phenomenon, therefore, our study aimed to explore the experiences and practices of THs regarding snakebite treatment and prevention in rural Malawi. Between August and September 2022, we conducted semi-structured interviews with 16 THs who were purposefully selected from various locations across Neno District, Malawi. We analysed the interview data using Dedoose software, where we generated codes and grouped them into themes. Out of the 16 THs interviewed, 68.8% (n = 11) were male, and 43.8% were aged between 40 and 60 years. Our study identified five themes: THs' knowledge of snakes and treatment, the continuum of care they provide, payment procedures, snakebite prevention, and their relationship with health facilities. They claimed a good understanding of the snakes in their area, including the seasons with more snakebites, and were confident in their ability to provide treatment, however, this was not scientifically proven. They offered a comprehensive care package, including diagnosis, first aid, main treatment, and follow-up care to monitor the victim's condition and adjust treatment as needed. THs provide free treatment for snakebites or use a "pay later" model of service delivery. All THs claimed a "vaccine" for snakebites that could prevent bites or neutralize the venom. However, no formal relationship existed between THs and Health Care Workers (HCWs). We recommend collaboration between HCWs and THs, establishing clear referral pathways for snakebite victims and educating THs on identifying danger signs requiring prompt referral to healthcare facilities.
Topics: Animals; Humans; Male; Adult; Middle Aged; Female; Snake Bites; Traditional Medicine Practitioners; Malawi; Snakes; First Aid; Antivenins
PubMed: 37792697
DOI: 10.1371/journal.pntd.0011653 -
Scientific Reports Jan 2024Climate change and human activity threaten sea turtle nesting beaches through increased flooding and erosion. Understanding the environmental characteristics that enable...
Climate change and human activity threaten sea turtle nesting beaches through increased flooding and erosion. Understanding the environmental characteristics that enable nesting can aid to preserve and expand these habitats. While numerous local studies exist, a comprehensive global analysis of environmental influences on the distribution of sea turtle nesting habitats remains largely unexplored. Here, we relate the distribution of global sea turtle nesting to 22 coastal indicators, spanning hydrodynamic, atmospheric, geophysical, habitat, and human processes. Using state-of-the-art global datasets and a novel 50-km-resolution hexagonal coastline grid (Coastgons), we employ machine learning to identify spatially homogeneous patterns in the indicators and correlate these to the occurrence of nesting grounds. Our findings suggest sea surface temperature, tidal range, extreme surges, and proximity to coral and seagrass habitats significantly influence global nesting distribution. Low tidal ranges and low extreme surges appear to be particularly favorable for individual species, likely due to reduced nest flooding. Other indicators, previously reported as influential (e.g., precipitation and wind speed), were not as important in our global-scale analysis. Finally, we identify new, potentially suitable nesting regions for each species. On average, [Formula: see text] of global coastal regions between [Formula: see text] and [Formula: see text] latitude could be suitable for nesting, while only [Formula: see text] is currently used by turtles, showing that the realized niche is significantly smaller than the fundamental niche, and that there is potential for sea turtles to expand their nesting habitat. Our results help identify suitable nesting conditions, quantify potential hazards to global nesting habitats, and lay a foundation for nature-based solutions to preserve and potentially expand these habitats.
Topics: Humans; Animals; Turtles; Anthozoa; Climate Change; Computer Systems; Floods
PubMed: 38191897
DOI: 10.1038/s41598-023-50239-5 -
Toxins Sep 2023Snake venoms constitute a complex, rapidly evolving trait, whose composition varies between and within populations depending on geographical location, age and preys...
Snake venoms constitute a complex, rapidly evolving trait, whose composition varies between and within populations depending on geographical location, age and preys (diets). These factors have determined the adaptive evolution for predatory success and link venom heterogeneity with prey specificity. Moreover, understanding the evolutionary drivers of animal venoms has streamlined the biodiscovery of venom-derived compounds as drug candidates in biomedicine and biotechnology. The king cobra (; Cantor, 1836) is distributed in diverse habitats, forming independent populations, which confer differing scale markings, including between hatchlings and adults. Furthermore, king cobra venoms possess unique cytotoxic properties that are used as a defensive trait, but their toxins may also have utility as promising anticancer-agent candidates. However, the impact of geographical distribution and age on these potential venom applications has been typically neglected. In this study, we hypothesised that ontogenetic venom variation accompanies the morphological distinction between hatchlings and adults. We used non-transformed neonatal foreskin (NFF) fibroblasts to examine and compare the variability of venom cytotoxicity between adult captive breeding pairs from Malaysian and Chinese lineages, along with that of their progeny upon hatching. In parallel, we assessed the anticancer potential of these venoms in human-melanoma-patient-derived cells (MM96L). We found that in a geographical distribution and gender-independent manner, venoms from hatchlings were significantly less cytotoxic than those from adults (NFF; ~Log EC: 0.5-0.6 vs. 0.2-0.35 mg/mL). This is consistent with neonates occupying a semifossorial habitat, while adults inhabit more above-ground habitats and are therefore more conspicuous to potential predators. We also observed that Malaysian venoms exhibited a slightly higher cytotoxicity than those from the Chinese cobra cohorts (NFF; Log EC: 0.1-0.3 vs. 0.3-0.4 mg/mL), which is consistent with Malaysian king cobras being more strongly aposematically marked. These variations are therefore suggestive of differential anti-predator strategies associated with the occupation of distinct niches. However, all cobra venoms were similarly cytotoxic in both melanoma cells and fibroblasts, limiting their potential medical applications in their native forms.
Topics: Adult; Animals; Humans; Infant, Newborn; Male; Elapid Venoms; Foreskin; Geography; Melanoma; Ophiophagus hannah; Fibroblasts
PubMed: 37755975
DOI: 10.3390/toxins15090549 -
Toxicon : Official Journal of the... Jun 2024Around 95% of snake venom is protein. Along with the soluble proteins, snake venom also contains proteins encapsulated in vesicles known as Snake Venom Extracellular... (Review)
Review
Around 95% of snake venom is protein. Along with the soluble proteins, snake venom also contains proteins encapsulated in vesicles known as Snake Venom Extracellular Vesicles (SVEV). SVEVs are nano-sized membrane-bound vesicles released from the snake venom gland cells. The available published research works on SVEVs are minimal. Extracellular vesicles in the Snake Venom gland were initially discovered during the histopathological analysis of the Crotalus durissus terrificus snakes' venom gland. Later, various techniques were employed to isolate and characterize the SVEVs. The cargo of SVEV consists of a variety of proteins like Phospholipase A-2, C-type Lectins, L-Amino Acid Oxidase, Cysteine-Rich Secretory Proteins, Serine Proteinases, Dipeptidyl Peptidase-IV, Aminopeptidase-A, Ecto-5'-nucleotidases, Disintegrins. Proteomic data revealed the presence of some exclusive proteins in the SVEVs, and the other proteins are in varying concentrations in the SVEVs compared to their whole Venom. Interaction of SVEVs with mammalian cell lines showed the disruption of primary physiological functions leads to host immune modulation, and long-term effects of envenoming. Snakebite victim's blood showed variations in the specific Extracellular vesicle concentration. It has been hypothesized that SVEVs are responsible for long-term toxicity. The current review focuses on the various techniques adopted to isolate and characterize SVEVs and discusses the exclusiveness and variations of SVEV proteins and their role in snakebites.
Topics: Extracellular Vesicles; Animals; Snake Venoms; Proteomics; Crotalus
PubMed: 38768828
DOI: 10.1016/j.toxicon.2024.107772 -
Scientific Reports Jul 2023Dinosaurs and mammals have coexisted for the last ~ 230 million years. Both groups arose during the Late Triassic and diversified throughout the Mesozoic and into...
Dinosaurs and mammals have coexisted for the last ~ 230 million years. Both groups arose during the Late Triassic and diversified throughout the Mesozoic and into the Cenozoic (the latter in the form of birds). Although they undoubtedly interacted in many ways, direct fossil evidence for their interaction is rare. Here we report a new fossil find from the Lujiatun Member of the Lower Cretaceous Yixian Formation of China, showing a gobiconodontid mammal and psittacosaurid dinosaur locked in mortal combat. We entertain various hypothesized explanations for this association, but the balance of the evidence suggests that it represents a predation attempt on the part of the smaller mammal, suddenly interrupted by, and preserved within, a lahar-type volcanic debris flow. Mesozoic mammals are usually depicted as having lived in the shadows of their larger dinosaurian contemporaries, but this new fossil convincingly demonstrates that mammals could pose a threat even to near fully-grown dinosaurs. The Yixian Formation-and the Chinese fossil Jehol Biota more broadly-have played a particularly important role in revealing the diversity of small-bodied dinosaurs and other fauna. We anticipate that the volcanically derived obrution deposits specific to the Lujiatun Member will likewise continue to yield evidence for biotic interactions otherwise unknown from the rest of the fossil record.
Topics: Animals; Fossils; Dinosaurs; Birds; Mammals; Predatory Behavior; Biological Evolution; Phylogeny
PubMed: 37464026
DOI: 10.1038/s41598-023-37545-8 -
PLoS Neglected Tropical Diseases Jul 2023Snake bite envenoming (SBE) is one neglected tropical disease that has not received the needed attention. The sequelae of burdensome disability and mortality impact the...
BACKGROUND
Snake bite envenoming (SBE) is one neglected tropical disease that has not received the needed attention. The sequelae of burdensome disability and mortality impact the socioeconomic life of communities adversely with little documentation of SBE in health facility records in Ghana. This study details SBE and snake distribution, habits/habitats, type of venom expressed and clinical manifestations.
METHODOLOGY
We conducted a structured thematic desk review of peer reviewed papers, books and reports from repositories including PubMed, World Health Organization (WHO) and Women's & Children's Hospital (WCH) Clinical Toxinology Resources using bibliographic software EndNote and search engine Google Scholar with the following key words; snakes, medical importance, snake bites, venom and venom type, envenomation, symptoms and signs, vaccines, venom expenditure, strike behaviour and venom-metering + Ghana, West Africa, Africa, World. We also reviewed data from the District Health Information Management System (DHIMS) of the Ghana Health Service (GHS). Outcome variables were organized as follows: common name (s), species, habitat/habit, species-specific toxin, clinical manifestation, antivenom availability, WHO category.
FINDINGS
Snake bites and SBE were grouped by the activity of the expressed venom into neurotoxic, cardiotoxic, haemorrhagic, cytotoxic, myotoxic, nephrotoxic and procoagulants. Neurotoxic snake bites were largely due to elapids. Expressed venoms with cardiotoxic, haemorrhagic, nephrotoxic and procoagulant activities principally belonged to the family Viperidae. Snakes with venoms showing myotoxic activity were largely alien to Ghana and the West African sub-region. Venoms showing cytotoxic activity are expressed by a wide range of snakes though more prevalent among the Viperidae family. Snakes with neurotoxic and haemorrhagic venom activities are prevalent across all the agro-ecological zones in Ghana.
CONCLUSION/SIGNIFICANCE
Understanding the characteristics of snakes and their venoms is useful in the management of SBE. The distribution of snakes by their expressed venoms across the agro-ecological zones is also instructive to species identification and diagnosis of SBE.
Topics: Animals; Antivenins; Elapid Venoms; Elapidae; Ghana; Snake Bites; Snake Venoms; Snakes; Viperidae
PubMed: 37506181
DOI: 10.1371/journal.pntd.0011050 -
Communications Biology Sep 2023Long noncoding RNAs have been identified in most vertebrates, but the functional characterization of these molecules is challenging, mainly due to the lack of linear...
Long noncoding RNAs have been identified in most vertebrates, but the functional characterization of these molecules is challenging, mainly due to the lack of linear sequence homology between species. In this work, we aimed to find functional evolutionary convergent lncRNAs involved in development by screening of k-mer content (nonlinear similarity) and secondary structure-based approaches combining in silico, in vitro and in vivo validation analysis. From the Madagascar gecko genes, we have found a non-orthologous lncRNA with a similar k-mer content and structurally concordant with the human lncRNA EVX1AS. Analysis of function-related characteristics together with locus-specific targeting of human EVX1AS and gecko EVX1AS-like (i.e., CRISPR Display) in human neuroepithelial cells and chicken mesencephalon have confirmed that gecko EVX1AS-like lncRNA mimics human EVX1AS function and induces EVX1 expression independently of the target species. Our data shows functional convergence of non-homologous lncRNAs and presents a useful approach for the definition and manipulation of lncRNA function within different model organisms.
Topics: Animals; Female; Humans; Biological Evolution; Embryonic Development; Lizards; RNA, Long Noncoding
PubMed: 37670146
DOI: 10.1038/s42003-023-05278-z -
PeerJ 2023On Caribbean coral reefs, losses of two key groups of grazers, herbivorous fishes and , coincided with dramatic increases in macroalgae, which have contributed to...
On Caribbean coral reefs, losses of two key groups of grazers, herbivorous fishes and , coincided with dramatic increases in macroalgae, which have contributed to decreases in the resilience of these coral reefs and continued low coral cover. In some locations, herbivorous reef fishes and populations have begun to recover, and reductions in macroalgal cover and abundance have followed. Harder to determine, and perhaps more important, are the combined grazing effects of herbivorous fishes and on the structure of macroalgal communities. Surprisingly few studies have examined the feeding preferences of for different macroalgal species, and there have been even fewer comparative studies between these different herbivore types. Accordingly, a series of in-situ and ex-situ feeding assays involving herbivorous fishes and were used to examine feeding preferences. Ten macrophytes representing palatable and chemically and/or structurally defended species were used in these assays, including nine macroalgae, and one seagrass. All species were eaten by at least one of the herbivores tested, although consumption varied greatly. All herbivores consumed significant portions of two red algae species while avoiding , which has both chemical and structural defenses. Herbivorous fishes mostly avoided chemically defended species while consumed less of the structurally defended algae. These results suggest complementarity and redundancy in feeding by these different types of herbivores indicating the most effective macroalgal control and subsequent restoration of degraded coral reefs may depend on the recovery of both herbivorous fishes and .
Topics: Animals; Herbivory; Alligators and Crocodiles; Coral Reefs; Sea Urchins; Seaweed; Fishes
PubMed: 38025680
DOI: 10.7717/peerj.16264 -
Veterinary Medicine and Science Nov 2023The Greek or Mediterranean tortoise (Testudo graeca), commonly known as the spur-thighed tortoise, is a species of tortoise in the family Testudinidae that is found in...
BACKGROUND
The Greek or Mediterranean tortoise (Testudo graeca), commonly known as the spur-thighed tortoise, is a species of tortoise in the family Testudinidae that is found in North Africa, Western Asia and Europe. Several species of this genus are under threat in the wild, mainly from habitat destruction therefore, accurate information about the sexual cycle and the exact time of follicular development can be effective in successful reproduction planning and preventing species extinction.
OBJECTIVE
The experimental part of this study is focused on the evaluation of the reproductive apparatus of tortoises and development of follicles in ovaries during 1 year by ultrasonography and computed tomography.
METHODS
Ultrasonography and CT scanning was carried out on 10 female 'T. Graeca' tortoises which were maintained at Tehran Eram Zoo from November 2021 to November 2022 (1 year). Ultrasonography and CT exams were performed on all animals.
RESULTS
In the first study, on 28 November 2021, the ovarian cycle was characterized by the presence of previtellogenic follicles and atretic follicles. The numbers of follicles were best demonstrated on CT examination. Ultrasonography and CT scan in the second study showed no change in type of follicles from previous study. In the third study, atretic follicles were more than previtellogenic follicles, whereas in the fourth one, the numbers of previtellogenic follicles were more than atretic follicles. In following, at 6 and 29 June 2022, the absence of atretic follicles and just presence of previtellogenic follicles were observed. On 20 July 2022, the presence of a few number of atretic follicles and more previtellogenic follicles were noticed. On 30 July 2022, the absence of atretic follicles and presence of previtellogenic follicles and, for the first time, preovulatory follicles were obvious. In four following studies the absence of atretic follicles and the presence of previtellogenic follicles were diagnosed. In the last study, the absence of atretic follicles and the presence of preovulatory and previtellogenic follicles were observed.
CONCLUSION
In current study, the reproductive cycle of female T. Graeca is evaluated during 1 year in captivity with ultrasonography and CT scan. It can be concluded that in captivity, the reproductive cycle does not result in the formation of eggs or calcareous shells and atretic follicles in the study year continued as before; so this should be highly considered in captivity breeding programmes. This study also revealed that among imaging modalities, CT scan is the best modality for detecting the shape, size, type and numbers of the follicles for further evaluation of location and shape of the follicles.
Topics: Animals; Female; Turtles; Iran; Ovary; Ovarian Follicle; Ultrasonography
PubMed: 37669425
DOI: 10.1002/vms3.1259