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1.
Genome Biol Evol ; 15(1)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36648250

RESUMO

For aerobic organisms, both the hypoxia-inducible factor pathway and the mitochondrial genomes are key players in regulating oxygen homeostasis. Recent work has suggested that these mechanisms are not as highly conserved as previously thought, prompting more surveys across animal taxonomic levels, which would permit testing of hypotheses about the ecological conditions facilitating evolutionary loss of such genes. The Phylum Cnidaria is known to harbor wide variation in mitochondrial chromosome morphology, including an extreme example, in the Myxozoa, of mitochondrial genome loss. Because myxozoans are obligate endoparasites, frequently encountering hypoxic environments, we hypothesize that variation in environmental oxygen availability could be a key determinant in the evolution of metabolic gene networks associated with oxygen-sensing, hypoxia-response, and energy production. Here, we surveyed genomes and transcriptomes across 46 cnidarian species for the presence of HIF pathway members, as well as for an assortment of hypoxia, mitochondrial, and stress-response toolkit genes. We find that presence of the HIF pathway, as well as number of genes associated with mitochondria, hypoxia, and stress response, do not vary in parallel to mitochondrial genome morphology. More interestingly, we uncover evidence that myxozoans have lost the canonical HIF pathway repression machinery, potentially altering HIF pathway functionality to work under the specific conditions of their parasitic lifestyles. In addition, relative to other cnidarians, myxozoans show loss of large proportions of genes associated with the mitochondrion and involved in response to hypoxia and general stress. Our results provide additional evidence that the HIF regulatory machinery is evolutionarily labile and that variations in the canonical system have evolved in many animal groups.


Assuntos
Cnidários , Myxozoa , Animais , Cnidários/metabolismo , Oxigênio/metabolismo , Myxozoa/genética , Hipóxia/genética , Homeostase , Subunidade alfa do Fator 1 Induzível por Hipóxia
2.
Sci Adv ; 9(4): eadd2873, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36706182

RESUMO

During meiosis, DNA recombination allows the shuffling of genetic information between the maternal and paternal chromosomes. Recombination is initiated by double-strand breaks (DSBs) catalyzed by the conserved enzyme Spo11. How this crucial event is connected to other meiotic processes is unexpectedly variable depending on the species. Here, we knocked down Spo11 by CRISPR in the jellyfish Clytia hemisphaerica. Germ cells in Clytia Spo11 mutants fail to assemble synaptonemal complexes and chiasmata, and in consequence, homologous chromosome pairs in females remain unassociated during oocyte growth and meiotic divisions, creating aneuploid but fertilizable eggs that develop into viable larvae. Clytia thus shares an ancient eukaryotic dependence of synapsis and chromosome segregation on Spo11-generated DSBs. Phylogenetically, Clytia belongs to Cnidaria, the sister clade to Bilateria where classical animal model species are found, so these results provide fresh evolutionary perspectives on meiosis regulation.


Assuntos
Cnidários , Animais , Feminino , Cromossomos , Meiose/genética , Células Eucarióticas
3.
Mar Pollut Bull ; 186: 114462, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36521364

RESUMO

Massive blooms of Nemopilema nomurai have occurred recently across East Asian waters. They are potentially important as zooplankton predators, as well as being competitors for prey with zooplanktivorous fish. Few studies have estimated the predation effects on zooplankton by N. nomurai in situ. To quantify the natural diets and feeding rates and estimate the predation effects, N. nomurai medusae were collected in the northern East China Sea and southern Yellow Sea, one of the principal nursery grounds of this jellyfish, during May 2019. The gut contents indicated that copepods were an important food source for N. nomurai; copepods <1000 µm represented the bulk of total prey intake in number (> 99 %). Linear regression analyses showed that the copepods number in the gut contents was significantly influenced by medusa diameter and prey abundance. Calculations using the above data indicated that one medusa (mean diameter: 26.06 ± 9.73 cm) consumed approximately 5248 ± 2768 of copepods daily. However, even the maximum predation pressure was <0.1 % of the total copepods standing stock daily due to the small diameter and low density/biomass of N. nomurai medusae in May 2019. The data presented here suggested that the predation effects of N. nomurai on copepods were low and might not reduce prey availability to fish with diets consisting mainly of copepods during the early occurrence stage of the N. nomurai population.


Assuntos
Cnidários , Copépodes , Cifozoários , Animais , Comportamento Predatório , Zooplâncton
4.
Genome Biol Evol ; 15(1)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36508343

RESUMO

Hox and ParaHox transcription factors are important for specifying cell fates along the primary body axes during the development of most animals. Within Cnidaria, much of the research on Hox/ParaHox genes has focused on Anthozoa (anemones and corals) and Hydrozoa (hydroids) and has concentrated on the evolution and function of cnidarian Hox genes in relation to their bilaterian counterparts. Here we analyze together the full complement of Hox and ParaHox genes from species representing all four medusozoan classes (Staurozoa, Cubozoa, Hydrozoa, and Scyphozoa) and both anthozoan classes (Octocorallia and Hexacorallia). Our results show that Hox genes involved in patterning the directive axes of anthozoan polyps are absent in the stem leading to Medusozoa. For the first time, we show spatial and temporal expression patterns of Hox and ParaHox genes in the upside-down jellyfish Cassiopea xamachana (Scyphozoa), which are consistent with diversification of medusozoan Hox genes both from anthozoans and within medusozoa. Despite unprecedented taxon sampling, our phylogenetic analyses, like previous studies, are characterized by a lack of clear homology between most cnidarian and bilaterian Hox and Hox-related genes. Unlike previous studies, we propose the hypothesis that the cnidarian-bilaterian ancestor possessed a remarkably large Hox complement and that extensive loss of Hox genes was experienced by both cnidarian and bilaterian lineages.


Assuntos
Antozoários , Cnidários , Animais , Cnidários/genética , Filogenia , Antozoários/genética , Genes Homeobox , Evolução Molecular
5.
Sci Total Environ ; 803: 149923, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34487898

RESUMO

While it is often assumed that oncogenic processes in metazoans can influence species interactions, empirical evidence is lacking. Here, we use the cnidarian Hydra oligactis to experimentally explore the consequences of tumor associated phenotypic alterations for its predation ability, relationship with commensal ciliates and vulnerability to predators. Unexpectedly, hydra's predation ability was higher in tumorous polyps compared to non-tumorous ones. Commensal ciliates colonized preferentially tumorous hydras than non-tumorous ones, and had a higher replication rate on the former. Finally, in a choice experiment, tumorous hydras were preferentially eaten by a fish predator. This study, for the first time, provides evidence that neoplastic growth has the potential, through effect(s) on host phenotype, to alter biotic interactions within ecosystems and should thus be taken into account by ecologists.


Assuntos
Cnidários , Hydra , Neoplasias , Animais , Ecossistema , Água Doce
6.
Folia Parasitol (Praha) ; 692022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36534003

RESUMO

A synopsis of 43 nominal species from five genera of tailed Myxobolidae infecting Indian freshwater and marine fishes is presented. The main characteristic of this group is the presence of at least one tail-like caudal process. For each species, relevant morphological and morphometric data are provided, such as the host(s), site(s) of infection within the host and sampling state. A key for the identification of 13 genera of tailed Myxobolidae is also included.


Assuntos
Cnidários , Doenças dos Peixes , Myxozoa , Doenças Parasitárias em Animais , Animais , Peixes , Filogenia
7.
Cells ; 11(24)2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36552730

RESUMO

Understanding the molecular underpinnings of the evolution of complex (multi-part) systems is a fundamental topic in biology. One unanswered question is to what the extent do similar or different genes and regulatory interactions underlie similar complex systems across species? Animal eyes and phototransduction (light detection) are outstanding systems to investigate this question because some of the genetics underlying these traits are well characterized in model organisms. However, comparative studies using non-model organisms are also necessary to understand the diversity and evolution of these traits. Here, we compare the characteristics of photoreceptor cells, opsins, and phototransduction cascades in diverse taxa, with a particular focus on cnidarians. In contrast to the common theme of deep homology, whereby similar traits develop mainly using homologous genes, comparisons of visual systems, especially in non-model organisms, are beginning to highlight a "deep diversity" of underlying components, illustrating how variation can underlie similar complex systems across taxa. Although using candidate genes from model organisms across diversity was a good starting point to understand the evolution of complex systems, unbiased genome-wide comparisons and subsequent functional validation will be necessary to uncover unique genes that comprise the complex systems of non-model groups to better understand biodiversity and its evolution.


Assuntos
Cnidários , Evolução Molecular , Animais , Opsinas/genética , Transdução de Sinal Luminoso/genética , Células Fotorreceptoras
8.
Toxins (Basel) ; 14(12)2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36548728

RESUMO

Jellyfish stings can result in local tissue damage and systemic pathophysiological sequelae. Despite constant occurrences of jellyfish stings in oceans throughout the world, the toxinological assessment of these jellyfish envenomations has not been adequately reported in quantitative as well as in qualitative measurements. Herein, we have examined and compared the in vivo toxic effects and pathophysiologic alterations using experimental animal models for two representative stinging jellyfish classes, i.e., Cubozoa and Scyphozoa. For this study, mice were administered with venom extracts of either Carybdea brevipedalia (Cnidaria: Cubozoa) or Nemopilema nomurai (Cnidaria: Scyphozoa). From the intraperitoneal (IP) administration study, the median lethal doses leading to the deaths of mice 24 h post-treatment after (LD50) for C. brevipedalia venom (CbV) and N. nomurai venom (NnV) were 0.905 and 4.4697 mg/kg, respectively. The acute toxicity (i.e., lethality) of CbV was much higher with a significantly accelerated time to death value compared with those of NnV. The edematogenic activity induced by CbV was considerably (83.57/25 = 3.343-fold) greater than NnV. For the evaluation of their dermal toxicities, the epidermis, dermis, subcutaneous tissues, and skeletal muscles were evaluated toxinologically/histopathologically following the intradermal administration of the venoms. The minimal hemorrhagic doses (MHD) of the venoms were found to be 55.6 and 83.4 µg/mouse for CbV and NnV, respectively. Furthermore, the CbV injection resulted in extensive alterations of mouse dermal tissues, including severe edema, and hemorrhagic/necrotic lesions, with the minimum necrotizing dose (MND) of 95.42 µg/kg body weight. The skin damaging effects of CbV appeared to be considerably greater, compared with those of NnV (MND = 177.99 µg/kg). The present results indicate that the toxicities and pathophysiologic effects of jellyfish venom extracts may vary from species to species. As predicted from the previous reports on these jellyfish envenomations, the crude venom extracts of C. brevipedalia exhibit much more potent toxicity than that of N. nomurai in the present study. These observations may contribute to our understanding of the toxicities of jellyfish venoms, as well as their mode of toxinological actions, which might be helpful for establishing the therapeutic strategies of jellyfish stings.


Assuntos
Cnidários , Venenos de Cnidários , Cubomedusas , Cifozoários , Animais , Camundongos , Venenos de Cnidários/toxicidade , Pele , Hemorragia
9.
Int Marit Health ; 73(4): 199-202, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36583407

RESUMO

An increasing presence on many beaches worldwide, jellyfish are a diverse group of Cnidarians equipped with stinging cells termed cnidocytes. Though few of the over 10,000 species are dangerous to humans, and most that are produce no more than a painful sting, some jellyfish can produce systemic symptoms and even death. Chironex fleckeri, the Australian box jellyfish, has a venom potent enough to kill in less than 10 minutes, and for which there is an antivenom of debatable efficacy. Stings from Carukia barnesi can cause Irukandji syndrome, characterised by severe pain and hypertension. Jellyfish stings have also been associated with Guillain-Barre syndrome and anaphylaxis. Though optimal treatment of stings remains controversial, after removal from the water and addressing any immediate life threats, the tentacles should be removed and the area washed, with seawater being the best choice due to its low likelihood of inducing further cnidocyte discharge. Hot water immersion may be beneficial for pain control for non-tropical jellyfish stings, and cold packs for tropical stings. In general, there is no consensus for the optimal treatment of jellyfish stings, and so further research is needed into species-specific guidelines and whether there are any overarching rules.


Assuntos
Mordeduras e Picadas , Cnidários , Venenos de Cnidários , Cubomedusas , Cifozoários , Animais , Humanos , Água , Austrália , Dor , Mordeduras e Picadas/terapia
10.
Front Cell Infect Microbiol ; 12: 1032347, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389158

RESUMO

Tetracapsuloides bryosalmonae is a malacosporean endoparasite that causes proliferative kidney disease (PKD) in wild and farmed salmonids in Europe and North America. The life cycle of T. bryosalmonae completes between invertebrate bryozoan and vertebrate fish hosts. Inside the fish, virulence factors of T. bryosalmonae are induced during infection or interactions with host cells. T. bryosalmonae genes expressed in vivo are likely to be important in fish pathogenesis. Herein, we identify in vivo induced antigens of T. bryosalmonae during infection in brown trout (Salmo trutta) using in vivo induced antigen technology (IVIAT). Brown trout were exposed to the spores of T. bryosalmonae and were sampled at different time points. The pooled sera were first pre-adsorbed with antigens to remove false positive results. Subsequently, adsorbed sera were used to screen a T. bryosalmonae cDNA phage expression library. Immunoscreening analysis revealed 136 immunogenic T. bryosalmonae proteins induced in brown trout during parasite development. They are involved in signal transduction, transport, metabolism, ion-protein binding, protein folding, and also include hypothetical proteins, of so far unknown functions. The identified in vivo induced antigens will be useful in the understanding of T. bryosalmonae pathogenesis during infection in susceptible hosts. Some of the antigens found may have significant implications for the discovery of candidate molecules for the development of potential therapies and preventive measures against T. bryosalmonae in salmonids.


Assuntos
Cnidários , Doenças dos Peixes , Nefropatias , Myxozoa , Parasitos , Doenças Parasitárias em Animais , Animais , Myxozoa/genética , Truta/parasitologia , Tecnologia
11.
Dis Aquat Organ ; 152: 1-7, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36394135

RESUMO

Kudoa thyrsites is a myxozoan parasite of marine fish with a global distribution. In British Columbia (BC), Canada, severe infections are associated with an economically significant degradation of fillet quality in farmed Atlantic salmon. Exposures to naturally occurring actinospores at a coastal research laboratory were used to test the hypothesis that the prevalence and severity of K. thyrsites infections acquired by exposure of Atlantic salmon to seawater (SW) of various depths are not different. In Expt 1, fish were exposed to SW from 1, 7 or 13 m below the surface. Following exposure to deeper-sourced SW, the prevalence of K. thyrsites, determined from microscopic examination of muscle histology sections, was greater in all 4 trials and the severity of infection was greater in 2 trials. In Expt 2, infections were compared over time among salmon held in tanks supplied with deep-sourced SW (raw or UV-irradiated) or in a surface net-pen. The infection was observed in 35 of 40 fish sampled between 3 and 6 mo after tank exposure to raw SW. Coincidentally, the parasite was observed in 4 of 40 fish maintained in the net-pen. No consistent association of the parasite infection was observed with temperature; however, reduced salinity and solar radiation were not ruled out as factors which may reduce the risk of infection from surface SW. These findings require verification at commercial aquaculture sites in BC, as they will inform considerations related to farm siting and net-pen configuration.


Assuntos
Cnidários , Doenças dos Peixes , Myxozoa , Salmo salar , Animais , Prevalência , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Água do Mar/parasitologia , Colúmbia Britânica/epidemiologia
12.
J Parasitol ; 108(6): 545-552, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36395189

RESUMO

Between November 2018 and December 2021, 35 juvenile and adult Western Creek Chubsuckers, Erimyzon claviformis, were collected from 5 sites in western and southern Arkansas (Ouachita and Red River drainages), and their gills, gallbladders, fins, integument, other major organs, and musculature were examined for myxozoans. The fins of 12 (34%) individuals were infected with a novel species, Myxobolus stuartae n. sp. Qualitative and quantitative morphological data were obtained from formalin-fixed preserved myxospores. Molecular data from ethanol-preserved specimens consisted of a 2,028 base pair sequence of small subunit (SSU) ribosomal DNA (rDNA) from a specimen collected in Nevada County. Three other specimens from Polk County yielded partial SSU rDNA sequences that were identical to the first sequence. Phylogenetic analyses placed M. stuartae n. sp. as sister to Myxobolus bibullatus (Kudo, 1934), both clustering with other catostomid-infecting myxobolids. This is the first fin-infecting myxozoan reported from E. claviformis.


Assuntos
Cnidários , Cipriniformes , Doenças dos Peixes , Myxobolus , Myxozoa , Humanos , Animais , Myxobolus/genética , Myxozoa/genética , Cnidários/genética , Filogenia , Arkansas/epidemiologia , Doenças dos Peixes/epidemiologia , DNA Ribossômico/genética
13.
Sci Rep ; 12(1): 19157, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36357444

RESUMO

The complexity of engineering optimization problems is increasing. Classical gradient-based optimization algorithms are a mathematical means of solving complex problems whose ability to do so is limited. Metaheuristics have become more popular than exact methods for solving optimization problems because of their simplicity and the robustness of the results that they yield. Recently, population-based bio-inspired algorithms have been demonstrated to perform favorably in solving a wide range of optimization problems. The jellyfish search optimizer (JSO) is one such bio-inspired metaheuristic algorithm, which is based on the food-finding behavior of jellyfish in the ocean. According to the literature, JSO outperforms many well-known meta-heuristics in a wide range of benchmark functions and real-world applications. JSO can also be used in conjunction with other artificial intelligence-related techniques. The success of JSO in solving diverse optimization problems motivates the present comprehensive discussion of the latest findings related to JSO. This paper reviews various issues associated with JSO, such as its inspiration, variants, and applications, and will provide the latest developments and research findings concerning JSO. The systematic review contributes to the development of modified versions and the hybridization of JSO to improve upon the original JSO and present variants, and will help researchers to develop superior metaheuristic optimization algorithms with recommendations of add-on intelligent agents.


Assuntos
Cnidários , Cifozoários , Animais , Inteligência Artificial , Algoritmos , Heurística , Resolução de Problemas
14.
Proc Biol Sci ; 289(1986): 20221623, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36321492

RESUMO

Exoskeletal dwelling tubes are widespread among extant animals and early fossil assemblages. Exceptional fossils from the Cambrian reveal independent origins of tube dwelling by several clades including cnidarians, lophophorates, annelids, scalidophorans, panarthropods and ambulacrarians. However, most fossil tubes lack preservation of soft parts, making it difficult to understand their affinities and evolutionary significance. Gangtoucunia aspera (Wulongqing Formation, Cambrian Stage 4) was an annulated, gradually expanding phosphatic tube, with occasional attachments of multiple, smaller juveniles and has previously been interpreted as the dwelling tube of a 'worm' (e.g. a scalidophoran), lophophorate or problematicum. Here, we report the first soft tissues from Gangtoucunia that reveal a smooth body with circumoral tentacles and a blind, spacious gut that is partitioned by septa. This is consistent with cnidarian polyps and phylogenetic analysis resolves Gangtoucunia as a total group medusozoan. The tube of Gangtoucunia is phenotypically similar to problematic annulated tubular fossils (e.g. Sphenothallus, Byronia, hyolithelminths), which have been compared to both cnidarians and annelids, and are among the oldest assemblages of skeletal fossils. The cnidarian characters of G. aspera suggest that these early tubular taxa are best interpreted as cnidarians rather than sessile bilaterians in the absence of contrary soft tissue evidence.


Assuntos
Cnidários , Animais , Filogenia , Fosfatos , Fósseis , Evolução Biológica , Preservação de Tecido
15.
PLoS One ; 17(11): e0276080, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36322524

RESUMO

The use of by-products of salted jellyfish for gelatin production offers valuable gelatin products rather than animal feed. Several washes or washing machines have reported removing salt in salted jellyfish. However, the green ultrasound technique has never been reported for the desalination of salted jellyfish. The objectives were to determine how effectively the raw material's salt removal was done by combining the traditional wash and then subjected to the ultrasonic waves in a sonication bath for 20-100 min. For gelatin production, the ultrasonicated jellyfish by-products were pretreated with sodium hydroxide and hydrochloric acid, washed, and extracted with hot water for 4, 6, and 8 h. Results showed that the increased duration of ultrasound time increased the desalination rate. The highest desalination rate of 100% was achieved using 100 min ultrasonic time operated at a fixed frequency (40 kHz) and power (220 W). The jellyfish gelatin extracted for 4, 6, and 8 h showed gel strengths in 121-447, 120-278, and 91-248 g. The 80 min ultrasonicated sample and hot water extraction for 8 h (JFG80-8) showed the highest gel yield of 32.69%, with a gel strength of 114.92 g. Still, the 40 min ultrasonicated sample with 4 h of extraction delivered the highest gel strength of 447.01 g (JFG40-4) and the lower yield of 10.60%. The melting and gelling temperatures of jellyfish gelatin from ultrasonicated samples ranged from 15-25°C and 5-12°C, which are lower than bovine gelatin (BG) and fish gelatin (FG). Monitored by FITR, the synergistic effect of extended sonication time (from 20-100 min) with 4 h extraction time at 80 °C caused amide I, II, and III changes. Based on the proteomic results, the peptide similarity of JFG40-4, having the highest gel strength, was 17, 23, or 20 peptides compared to either BG, FG, or JFG100-8 having the lowest gel strength. The 14 peptides were similarly found in all JFG40-4, BG, and FG samples. In conclusion, for the first time in this report, the improved jellyfish gel can be achieved when combined with traditional wash and 40 min ultrasonication of desalted jellyfish and extraction time of 4 h at 80 °C.


Assuntos
Cnidários , Gelatina , Animais , Bovinos , Proteômica , Géis , Coloides , Peixes , Cloreto de Sódio , Peptídeos , Água
16.
J Parasitol ; 108(5): 476-486, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36269893

RESUMO

During October and November 2021, 33 creek chubs, Semotilus atromaculatus, were collected from 3 sites in Polk County, Arkansas (Ouachita River drainage), and their gills, gallbladder, fins, integument, musculature, and other major organs were examined for myxozoans. The gills of 9 (27%) were infected with a new myxozoan, Myxobolus fountainae n. sp. Qualitative and quantitative morphological data were from fresh and formalin-fixed preserved spores, while molecular data consisted of a 1918 base pair sequence of the partial small subunit ribosomal RNA gene. Phylogenetic analysis grouped M. fountainae n. sp. with the other leuciscid-infecting myxobolids from North America and within a larger clade of European myxozoans. In addition, histological information is provided on the infection. A previous record of Myxobolus muelleriBütschli, 1882, from the gills and ureters of S. atromaculatus is considered invalid and represents an unknown species. Myxobolus fountainae n. sp. is the only named myxozoan known to infect the gill filaments of S. atromaculatus, whereas Myxobolus pendula (Guilford, 1967) infects the gill arches.


Assuntos
Cnidários , Cyprinidae , Cipriniformes , Doenças dos Peixes , Myxobolus , Myxozoa , Animais , Myxobolus/genética , Myxozoa/genética , Brânquias , Cnidários/genética , Filogenia , Arkansas/epidemiologia , RNA Ribossômico 18S/genética , Doenças dos Peixes/epidemiologia , DNA Ribossômico/genética , Formaldeído
17.
Dev Biol ; 492: 187-199, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36272560

RESUMO

Across eumetazoans, the ability to perceive and respond to visual stimuli is largely mediated by opsins, a family of proteins belonging to the G protein-coupled receptor (GPCR) superclass. Lineage-specific gains and losses led to a striking diversity in the numbers, types, and spectral sensitivities conferred by visual opsin gene expression. Here, we review the diversity of visual opsins and differences in opsin gene expression from well-studied protostome, invertebrate deuterostome, and cnidarian groups. We discuss the functional significance of opsin expression differences and spectral tuning among lineages. In some cases, opsin evolution has been linked to the detection of relevant visual signals, including sexually selected color traits and host plant features. In other instances, variation in opsins has not been directly linked to functional or ecological differences. Overall, the array of opsin expression patterns and sensitivities across invertebrate lineages highlight the diversity of opsins in the eumetazoan ancestor and the labile nature of opsins over evolutionary time.


Assuntos
Cnidários , Opsinas , Animais , Opsinas/genética , Cnidários/genética , Evolução Molecular , Filogenia , Invertebrados , Opsinas de Bastonetes/genética
18.
Int J Mol Sci ; 23(19)2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36232791

RESUMO

Jellyfishes are considered a new potential resource in food, pharmaceutical and biomedical industries. In these latter cases, they are studied as source of active principles but are also exploited to produce marine collagen. In the present work, jellyfish skin polysaccharides (JSP) with glycosaminoglycan (GAG) features were extracted from Rhizostoma pulmo, a main blooming species of Mediterranean Sea, massively augmented by climate leaded "jellyfishication" of the sea. Two main fractions of R. pulmo JSP (RP-JSPs) were isolated and characterized, namely a neutral fraction (RP-JSP1) and a sulphate rich, negatively charged fraction (RP-JSP2). The two fractions have average molecular weights of 121 kDa and 590 kDa, respectively. Their sugar composition was evaluated through LC-MS analysis and the result confirmed the presence of typical GAG saccharides, such as glucose, galactose, glucosamine and galactosamine. Their use as promoters of wound healing was evaluated through in vitro scratch assay on murine fibroblast cell line (BALB/3T3 clone A31) and human keratinocytes (HaCaT). Both RP-JSPs demonstrated an effective confluency rate activity leading to 80% of scratch repair in two days, promoting both cell migration and proliferation. Additionally, RP-JSPs exerted a substantial protection from oxidative stress, resulting in improved viability of treated fibroblasts exposed to H2O2. The isolated GAG-like polysaccharides appear promising as functional component for biomedical skin treatments, as well as for future exploitation as pharmaceutical excipients.


Assuntos
Cnidários , Cifozoários , Animais , Carboidratos , Colágeno/metabolismo , Excipientes , Fibroblastos/metabolismo , Galactosamina , Galactose , Glucosamina , Glucose , Glicosaminoglicanos , Humanos , Peróxido de Hidrogênio , Camundongos , Polissacarídeos/farmacologia , Cifozoários/metabolismo , Sulfatos , Cicatrização
19.
J Emerg Med ; 63(4): 507-519, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36229325

RESUMO

BACKGROUND: Extremity ischemia and necrosis after jellyfish envenomation can be mutilating and cause long-term functional deficits. The best way to manage these presentations is unknown. OBJECTIVE: The aim of this review was to establish an evidence-based consensus for the management of extremity ischemia after jellyfish envenomation. METHODS: A systematic review of cases of extremity ischemia and necrosis after envenomation by marine cnidarians was performed to clarify what is and what is not known about management and outcomes, to draw conclusions about how best to manage these rare presentations, and to establish an evidence-based algorithm. RESULTS: The ischemic sequelae of envenomation typically evolves over a few days. Close medical supervision is necessary to react promptly to the evolving clinical scenario. In the literature, 15 different pharmacologic classes have been used to manage these presentations. Only IV infusions of prostaglandin derivatives and intra-arterial thrombolytics have been found to improve the clinical picture and avoid the need for surgical fasciotomy and debridement in some cases. Anticoagulants, antiplatelet agents, steroids, antibiotics, and nitrates, which are among the most commonly prescribed pharmacologic agents, have not been observed to alter the clinical picture. CONCLUSIONS: Surgery for compartment syndrome and necrosis are common sequelae of extremity envenomation by marine cnidarians. Only prompt use of IV prostaglandins or intra-arterial thrombolytics can halt ischemic progression and avoid the need for surgery. An algorithm is proposed to guide management of these rare and mutilative presentations.


Assuntos
Cnidários , Síndromes Compartimentais , Animais , Humanos , Isquemia/complicações , Síndromes Compartimentais/etiologia , Síndromes Compartimentais/cirurgia , Extremidades , Necrose/complicações , Fibrinolíticos
20.
Mar Drugs ; 20(9)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36135760

RESUMO

Pelagia noctiluca stings are common in Mediterranean coastal areas and, although the venom is non-lethal, they are painful. Due to its high toxicity and abundance, P. noctiluca is considered a target species for the focus of research on active ingredients to reduce the symptoms of its sting. To determine the effect of 31 substances and formulations on nematocyst discharge, we performed three tests: (1) screening of per se discharge activator solutions, (2) inhibitory test with nematocyst chemical stimulation (5% acetic acid) and (3) inhibitory test quantifying the hemolytic area. Ammonia, barium chloride, bleach, scented ammonia, carbonated cola, lemon juice, sodium chloride and papain triggered nematocyst discharge. All of them were ruled out as potential inhibitors. Butylene glycol showed a reduction in nematocyst discharge, while the formulations of 10% lidocaine in ethanol, 1.5% hydroxyacetophenone in distilled water + butylene glycol, and 3% Symsitive® in butylene glycol inhibited nematocyst discharge. These last results were subsequently correlated with a significant decrease in hemolytic area in the venom assays versus seawater, a neutral solution. The presented data represent a first step in research to develop preventive products for jellyfish stings while at the same time attempting to clarify some uncertainties about the role of various topical solutions in P. noctiluca first-aid protocols.


Assuntos
Mordeduras e Picadas , Cnidários , Venenos de Cnidários , Cifozoários , Amônia/análise , Amônia/farmacologia , Animais , Mordeduras e Picadas/prevenção & controle , Butileno Glicóis/análise , Butileno Glicóis/farmacologia , Venenos de Cnidários/análise , Venenos de Cnidários/farmacologia , Etanol/farmacologia , Hemólise , Lidocaína/farmacologia , Nematocisto/química , Papaína/farmacologia , Cifozoários/química , Cloreto de Sódio/farmacologia , Água
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