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1.
Biomed Res Int ; 2021: 8855248, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33748281

RESUMO

Neurodegenerative diseases are one of the major causes of death worldwide, characterized by neurite atrophy, neuron apoptosis, and synapse loss. No effective treatment has been indicated for such diseases so far, and the search for new drugs is being increased in the last years. Animal venoms' secretion/venom can be an alternative for the discovery of new molecules, which could be the prototype for a new treatment. Here, we present the biochemical characterization and activity of the extract from the box jellyfish Chiropsalmus quadrumanus (Cq) on neurites. The Cq methanolic extract was obtained and incubated to human SH-SY5Y neurons, and neurite parameters were evaluated. The extract was tested in other cell types to check its cytotoxicity and was submitted to biochemical analysis by mass spectrometry in order to check its composition. We could verify that the Cq extract increased neurite outgrowth length and branching junctions, amplifying the contact between SH-SY5Y neurons, without affecting cell body and viability. The extract action was selective for neurons, as it did not cause any effects on other cell types, such as tumor line, nontumor line, and red blood cells. Moreover, mass spectrometry analysis revealed that there are no proteins but several low molecular mass compounds and peptides. Three peptides, characterized as cryptides, and 14 low molecular mass compounds were found to be related to cytoskeleton reorganization, cell membrane expansion, and antioxidant/neuroprotective activity, which act together to increase neuritogenesis. After this evaluation, we conclude that the Cq extract is a promising tool for neuronal connection recovery, an essential condition for the treatment of neurodegenerative diseases.


Assuntos
Misturas Complexas/farmacologia , Cubomedusas/química , Neuritos/metabolismo , Fármacos Neuroprotetores/farmacologia , Animais , Linhagem Celular Tumoral , Misturas Complexas/química , Humanos , Fármacos Neuroprotetores/química
2.
J Morphol ; 279(6): 841-856, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29570829

RESUMO

Cubozoans (box jellyfish) are gonochoristic cnidarians with distinct reproductive strategies. This comparative histological study examines the gonad organization of Alatina alata and Copula sivickisi, two box jellyfish species that exhibit different modes of internal fertilization. A. alata reproduces via spermcasting aggregations while C. sivickisi reproduces via copulation; in both cases, internal fertilization occurs in the gastrovascular cavity. Herein, we provide the first histological description of subgastric sacs-structures unique to C. sivickisi. Although previously thought to function as sperm storage sacs, our findings reveal that subgastric sacs are nematocyst nests lacking sperm entirely. Conversely, we discovered that velarial spots in C. sivickisi females correspond to actual sperm storage structures. Histological examination of cubozoan sperm packages revealed that while sperm packages from both species have motile flagella, A. alata males produce nonencapsulated sperm bundles (i.e., "spermatozeugmata"), and C. sivickisi males produce encapsulated packages (i.e., "spermatophores"). Our findings corroborate the presence of several types of nematocysts in C. sivickisi embryo strands and spermatophores, and indicate their provenance to be both female and male gonads respectively, as well as subgastric sacs (i.e., nematocyst nests). In contrast to our findings of velarial spots as sperm storages structures in C. sivickisi females, and of nematocysts in the gonads of both sexes, we report that A. alata medusae lack both sperm storage structures and gonadal nematocysts. Finally, we discuss our findings on reproductive morphology of C. sivickisi and A. alata in light of the respective reproductive behavior of these two cubozoan species.


Assuntos
Cubomedusas/anatomia & histologia , Animais , Cubomedusas/fisiologia , Feminino , Masculino , Reprodução/fisiologia
3.
PLoS One ; 12(7): e0181611, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28746410

RESUMO

Jellyfish blooms cause important ecological and socio-economic problems. Among jellyfish, cubozoans are infamous for their painful, sometimes deadly, stings and are a major public concern in tropical to subtropical areas; however, there is little information about the possible causes of their outbreaks. After a bloom of the cubomedusa Carybdea marsupialis (Carybdeidae) along the coast of Denia (SW Mediterranean, Spain) in 2008 with negative consequences for local tourism, the necessity to understand the ecological restrictions on medusae abundance was evident. Here we use different models (GAM and zero-inflated models) to understand the environmental and human related factors influencing the abundance and distribution of C. marsupialis along the coast of Denia. Selected variables differed among medusae size classes, showing different environmental restriction associated to the developmental stages of the species. Variables implicated with dispersion (e.g. wind and current) affected mostly small and medium size classes. Sea surface temperature, salinity and proxies of primary production (chl a, phosphates, nitrates) were related to the abundances of small and large size classes, highlighting the roles of springtime salinity changes and increased primary production that may promote and maintain high densities of this species. The increased primary (and secondary) production due to anthropogenic impact is implicated as the factor enabling high numbers of C. marsupialis to thrive. Recommendations for monitoring blooms of this species along the study area and applicable to Mediterranean Sea include focus effort in coastal waters where productivity have been enriched by anthropogenic activities.


Assuntos
Distribuição Animal/fisiologia , Cubomedusas/fisiologia , Salinidade , Temperatura , Animais , Ecossistema , Geografia , Humanos , Mar Mediterrâneo , Modelos Teóricos , Densidade Demográfica , Dinâmica Populacional , Estações do Ano , Água do Mar/química , Espanha , Análise Espaço-Temporal , Movimentos da Água , Vento
4.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;20: 1-5, 04/02/2014. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484604

RESUMO

Background The effectiveness of the currently available box jellyfish (Chironex fleckeri) antivenom has been subject of debate for many years. To assess whether the box jellyfish antivenom has the ability to attenuate venom-induced damage at cellular level, the present study analyzed the dose and time dependence of the antivenom in a cell-based assay.Methods Different doses of antivenom were added to venom and subsequently administered to cells and the cell index was measured using xCelligence Technology (ACEA Biosciences). Similarly, antivenom and venom were incubated over different time periods and cell survival measured as stated above. For both experiments, the cell index was plotted as a measure of cell survival against the dose or incubation time and significance was determined with the use of a one-way ANOVA with a LSD post hoctest.Results Increasing concentrations of antivenom significantly augmented cell survival, with a concentration of approximately five times the currently recommended dose for human envenomation, causing the first significant increase in cell survival compared venom alone. Further, cell survival improved with increasing incubation time of venom and antivenom prior to addition to the cells, indicating that box jellyfish antivenom requires approximately 70 minutes to neutralize C. fleckeri venom.Conclusion The presented results suggest that the currently recommended dose of antivenom requires adjustment, and more importantly, a human trial to test the effects of higher concentrations is also necessary. Further, antivenom has delayed neutralizing effects (i.e. after 70 minutes) which underlines the eminence of immediate and prolonged cardiopulmonary resuscitation in victims suffering from a C. fleckerivenom-induced cardiovascular collapse.


Assuntos
Animais , Antivenenos , Cubomedusas , Relação Dose-Resposta a Droga , Venenos de Cnidários/antagonistas & inibidores
5.
Artigo em Inglês | VETINDEX | ID: vti-18228

RESUMO

Background The effectiveness of the currently available box jellyfish (Chironex fleckeri) antivenom has been subject of debate for many years. To assess whether the box jellyfish antivenom has the ability to attenuate venom-induced damage at cellular level, the present study analyzed the dose and time dependence of the antivenom in a cell-based assay.Methods Different doses of antivenom were added to venom and subsequently administered to cells and the cell index was measured using xCelligence Technology (ACEA Biosciences). Similarly, antivenom and venom were incubated over different time periods and cell survival measured as stated above. For both experiments, the cell index was plotted as a measure of cell survival against the dose or incubation time and significance was determined with the use of a one-way ANOVA with a LSD post hoctest.Results Increasing concentrations of antivenom significantly augmented cell survival, with a concentration of approximately five times the currently recommended dose for human envenomation, causing the first significant increase in cell survival compared venom alone. Further, cell survival improved with increasing incubation time of venom and antivenom prior to addition to the cells, indicating that box jellyfish antivenom requires approximately 70 minutes to neutralize C. fleckeri venom.Conclusion The presented results suggest that the currently recommended dose of antivenom requires adjustment, and more importantly, a human trial to test the effects of higher concentrations is also necessary. Further, antivenom has delayed neutralizing effects (i.e. after 70 minutes) which underlines the eminence of immediate and prolonged cardiopulmonary resuscitation in victims suffering from a C. fleckerivenom-induced cardiovascular collapse.(AU)


Assuntos
Animais , Venenos de Cnidários/antagonistas & inibidores , Antivenenos , Relação Dose-Resposta a Droga , Cubomedusas
6.
Zootaxa ; 3737: 473-87, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25112765

RESUMO

Here we establish a neotype for Alatina alata (Reynaud, 1830) from the Dutch Caribbean island of Bonaire. The species was originally described one hundred and eighty three years ago as Carybdea alata in La Centurie Zoologique-a monograph published by René Primevère Lesson during the age of worldwide scientific exploration. While monitoring monthly reproductive swarms of A. alata medusae in Bonaire, we documented the ecology and sexual reproduction of this cubozoan species. Examination of forty six A. alata specimens and additional archived multimedia material in the collections of the National Museum of Natural History, Washington, DC revealed that A. alata is found at depths ranging from surface waters to 675 m. Additional studies have reported it at depths of up to 1607 m in the tropical and subtropical Atlantic Ocean. Herein, we resolve the taxonomic confusion long associated with A. alata due to a lack of detail in the original description and conflicting statements in the scientific literature. A new cubozoan character, the velarial lappet, is described for this taxon. The complete description provided here serves to stabilize the taxonomy of the second oldest box jellyfish species, and provide a thorough redescription of the species.


Assuntos
Cubomedusas/classificação , Animais , Cubomedusas/anatomia & histologia , Antilhas Holandesas
7.
J Travel Med ; 13(3): 166-71, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16706948

RESUMO

BACKGROUND: Jellyfish stings are a common occurrence among ocean goers worldwide with an estimated 150 million envenomations annually. Fatalities and hospitalizations occur annually, particularly in the Indo-Pacific regions. A new topical jellyfish sting inhibitor based on the mucous coating of the clown fish prevents 85% of jellyfish stings in laboratory settings. The field effectiveness is unknown. The objective is to evaluate the field efficacy of the jellyfish sting inhibitor, Safe Sea. METHODS: A double-blind, randomized, placebo-controlled trial occurred at the Dry Tortugas National Park, FL, USA and Sapodilla Cayes, Belize. Participants were healthy volunteers planning to snorkel for 30 to 45 minutes. Ten minutes prior to swimming, each participant was directly observed applying a blinded sample of Safe Sea (Nidaria Technology Ltd, Jordan Valley, Israel) to one side of their body and a blinded sample of Coppertone (Schering-Plough, Kenilworth, NJ, USA) to the contralateral side as placebo control. Masked 26 g samples of both Safe Sea SPF15 and Coppertone SPF15 were provided in identical containers to achieve 2 mg/cm(2) coverage. Sides were randomly chosen by participants. The incidence of jellyfish stings was the main outcome measure. This was assessed by participant interview and examination as subjects exited the water. RESULTS: A total of 82 observed water exposures occurred. Thirteen jellyfish stings occurred during the study period for a 16% incidence. Eleven jellyfish stings occurred with placebo, two with the sting inhibitor, resulting in a relative risk reduction of 82% (95% confidence interval: 21%-96%; p= 0.02). No seabather's eruption or side effects occurred. CONCLUSIONS: Safe Sea is a topical barrier cream effective at preventing >80% jellyfish stings under real-world conditions.


Assuntos
Antivenenos/administração & dosagem , Mordeduras e Picadas/prevenção & controle , Venenos de Cnidários/antagonistas & inibidores , Cubomedusas , Dermatite/prevenção & controle , Cifozoários , Administração Cutânea , Adulto , Animais , Belize , Mordeduras e Picadas/complicações , Dermatite/etiologia , Método Duplo-Cego , Feminino , Florida , Humanos , Masculino , Protetores Solares/administração & dosagem , Resultado do Tratamento
8.
Biota neotrop. (Online, Ed. port.) ; 6(2): 0-0, 2006. mapas
Artigo em Inglês, Português | LILACS | ID: lil-447609

RESUMO

Most of the scyphozoans and cubozoans recorded for the Brazilian coast are presumed to be distributed over the entire coastline, but little information on precise records is available. This paper presents the first published records for the Ceará state (northeastern region) of the cubozoan Chiropsalmus quadrumanus, and the scyphozoans Chrysaora lactea, Linuche unguiculata (polyp), Lychnorhiza lucerna, Nausithoe sp. (polyp), Phyllorhiza punctata, and Stomolophus meleagris. The medusoid species have been known by local fishermen and non-specialists for a long time in the area.


A maioria das cifomedusas e cubomedusas registradas para o litoral brasileiro é presumivelmente distribuída por toda a costa; porém poucos registros precisos estão disponíveis. Este estudo apresenta os primeiros registros publicados para o estado do Ceará (região Nordeste) da cubomedusa Chiropsalmus quadrumanus, e dos cifozoários: Chrysaora lactea, Linuche unguiculata (pólipo), Lychnorhiza lucerna, Nausithoe sp. (pólipo), Phyllorhiza punctata and Stomolophus meleagris. As espécies de medusas são conhecidas de longa data por pescadores locais e não-especialistas no grupo.


Assuntos
Cubomedusas/anatomia & histologia , Cubomedusas/crescimento & desenvolvimento , Fauna Marinha/análise , Fauna Marinha/classificação , Cifozoários/classificação , Cifozoários/crescimento & desenvolvimento
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