Resumo
The genus Conus includes over 900 species of marine invertebrates known as cone snails, whose venoms are among the most powerful described so far. This potency is mainly due to the concerted action of hundreds of small bioactive peptides named conopeptides, which target different ion channels and membrane receptors and thus interfere with crucial physiological processes. By swiftly harpooning and injecting their prey and predators with such deadly cocktails, the slow-moving cone snails guarantee their survival in the harsh, competitive marine environment. Each cone snail species produces a unique venom, as the mature sequences of conopeptides from the venoms of different species share very little identity. This biochemical diversity, added to the numerous species and conopeptides contained in their venoms, results in an immense biotechnological and therapeutic potential, still largely unexplored. That is especially true regarding the bioprospection of the venoms of cone snail species found off the Brazilian coast - a region widely known for its biodiversity. Of the 31 species described in this region so far, only four - Conus cancellatus, Conus regius, Conus villepinii, and Conus ermineus - have had their venoms partially characterized, and, although many bioactive molecules have been identified, only a few have been actually isolated and studied. In addition to providing an overview on all the cone snail species found off the Brazilian coast to date, this review compiles the information on the structural and pharmacological features of conopeptides and other molecules identified in the venoms of the four aforementioned species, paving the way for future studies.(AU)
Assuntos
Animais , Venenos/síntese química , Caramujos/fisiologia , Conotoxinas/análise , Compostos FitoquímicosResumo
This study presents a four-year follow-up of an introduced population of Physa acuta Draparnaud, 1805, from initial stages to an established population. This introduction occurred on a small impacted stream of Vila do Abraão, the main village of Ilha Grande (Angra dos Reis, Rio de Janeiro, Brazil). The population size increased during the study, and presented a relationship to environmental factors, especially with rainfall. On the initial stages of introduction prevailed the smaller specimens, but on the overall, predominated the intermediate size classes. After less than a year, P. acuta becomes established on this stream and was possibly affecting the other species found on the stream. The information presented here is useful to understand the invasion process of invasive snails, as well as directing conservation efforts.
Neste estudo é apresentado um acompanhamento de quatro anos de uma população de Physa acuta Draparnaud, 1805, desde os estágios iniciais da introdução até seu pleno estabelecimento. Esta introdução ocorreu em um pequeno riacho impactado da Vila do Abraão, o principal vilarejo da Ilha Grande (Angra dos Reis, Rio de Janeiro, Brasil). A população cresceu durante o estudo, e apresentou uma relação com os fatores ambientais, especialmente a pluviosidade. Nos estágios iniciais de introdução prevaleceram os exemplares menores, contudo no panorama geral, predominaram as classes de tamanho intermediárias. Em menos de um ano de introdução, P. acuta se estabeleceu neste riacho, e possivelmente está afetando as demais espécies encontradas no rio. A informação apresentada aqui é importante para a compreensão do processo de invasão de moluscos invasores no Brasil, assim como no direcionamento de esforços de conservação.
Assuntos
Animais , Espécies Introduzidas , Gastrópodes/crescimento & desenvolvimentoResumo
Abstract This study presents a four-year follow-up of an introduced population of Physa acuta Draparnaud, 1805, from initial stages to an established population. This introduction occurred on a small impacted stream of Vila do Abraão, the main village of Ilha Grande (Angra dos Reis, Rio de Janeiro, Brazil). The population size increased during the study, and presented a relationship to environmental factors, especially with rainfall. On the initial stages of introduction prevailed the smaller specimens, but on the overall, predominated the intermediate size classes. After less than a year, P. acuta becomes established on this stream and was possibly affecting the other species found on the stream. The information presented here is useful to understand the invasion process of invasive snails, as well as directing conservation efforts.
Resumo Neste estudo é apresentado um acompanhamento de quatro anos de uma população de Physa acuta Draparnaud, 1805, desde os estágios iniciais da introdução até seu pleno estabelecimento. Esta introdução ocorreu em um pequeno riacho impactado da Vila do Abraão, o principal vilarejo da Ilha Grande (Angra dos Reis, Rio de Janeiro, Brasil). A população cresceu durante o estudo, e apresentou uma relação com os fatores ambientais, especialmente a pluviosidade. Nos estágios iniciais de introdução prevaleceram os exemplares menores, contudo no panorama geral, predominaram as classes de tamanho intermediárias. Em menos de um ano de introdução, P. acuta se estabeleceu neste riacho, e possivelmente está afetando as demais espécies encontradas no rio. A informação apresentada aqui é importante para a compreensão do processo de invasão de moluscos invasores no Brasil, assim como no direcionamento de esforços de conservação.
Resumo
Abstract This study presents a four-year follow-up of an introduced population of Physa acuta Draparnaud, 1805, from initial stages to an established population. This introduction occurred on a small impacted stream of Vila do Abraão, the main village of Ilha Grande (Angra dos Reis, Rio de Janeiro, Brazil). The population size increased during the study, and presented a relationship to environmental factors, especially with rainfall. On the initial stages of introduction prevailed the smaller specimens, but on the overall, predominated the intermediate size classes. After less than a year, P. acuta becomes established on this stream and was possibly affecting the other species found on the stream. The information presented here is useful to understand the invasion process of invasive snails, as well as directing conservation efforts.
Resumo Neste estudo é apresentado um acompanhamento de quatro anos de uma população de Physa acuta Draparnaud, 1805, desde os estágios iniciais da introdução até seu pleno estabelecimento. Esta introdução ocorreu em um pequeno riacho impactado da Vila do Abraão, o principal vilarejo da Ilha Grande (Angra dos Reis, Rio de Janeiro, Brasil). A população cresceu durante o estudo, e apresentou uma relação com os fatores ambientais, especialmente a pluviosidade. Nos estágios iniciais de introdução prevaleceram os exemplares menores, contudo no panorama geral, predominaram as classes de tamanho intermediárias. Em menos de um ano de introdução, P. acuta se estabeleceu neste riacho, e possivelmente está afetando as demais espécies encontradas no rio. A informação apresentada aqui é importante para a compreensão do processo de invasão de moluscos invasores no Brasil, assim como no direcionamento de esforços de conservação.
Assuntos
Animais , Caramujos , Brasil , Densidade DemográficaResumo
This study presents a four-year follow-up of an introduced population of Physa acuta Draparnaud, 1805, from initial stages to an established population. This introduction occurred on a small impacted stream of Vila do Abraão, the main village of Ilha Grande (Angra dos Reis, Rio de Janeiro, Brazil). The population size increased during the study, and presented a relationship to environmental factors, especially with rainfall. On the initial stages of introduction prevailed the smaller specimens, but on the overall, predominated the intermediate size classes. After less than a year, P. acuta becomes established on this stream and was possibly affecting the other species found on the stream. The information presented here is useful to understand the invasion process of invasive snails, as well as directing conservation efforts.(AU)
Neste estudo é apresentado um acompanhamento de quatro anos de uma população de Physa acuta Draparnaud, 1805, desde os estágios iniciais da introdução até seu pleno estabelecimento. Esta introdução ocorreu em um pequeno riacho impactado da Vila do Abraão, o principal vilarejo da Ilha Grande (Angra dos Reis, Rio de Janeiro, Brasil). A população cresceu durante o estudo, e apresentou uma relação com os fatores ambientais, especialmente a pluviosidade. Nos estágios iniciais de introdução prevaleceram os exemplares menores, contudo no panorama geral, predominaram as classes de tamanho intermediárias. Em menos de um ano de introdução, P. acuta se estabeleceu neste riacho, e possivelmente está afetando as demais espécies encontradas no rio. A informação apresentada aqui é importante para a compreensão do processo de invasão de moluscos invasores no Brasil, assim como no direcionamento de esforços de conservação.(AU)
Assuntos
Animais , Gastrópodes/crescimento & desenvolvimento , Espécies IntroduzidasResumo
Megaspiridae include land snails with a tall spire. They occur in Brazil, New Guinea and Australia. Megaspira Lea, 1839 is distributed through the central and southeast regions of Brazil There is controversy regarding the number of species in the genus, and their taxonomic status. The characters used to identify Megaspira include a large cylindrical shell and internal armature in the columella. The goal of the present study is to describe a new species for the genus, based on shell morphology, microsculpture and the inner anatomy. These anatomic characters had not been described before for any of the included species. The material was collected at the Jararaca trail, Ilha Grande (Angra dos Reis, state of Rio de Janeiro). Seven linear measurements were taken from the shells. Megaspira adenticulata sp. nov. differs from the other species of the genus by not having apertural lamella in the shell aperture or in the columella in adult specimens. Also, the shell does not have light brown spots, as observed in other species of Megaspira. The shell has a mean of 16 whorls and height of 27 mm. It is smaller in average size than the shell of other described species. The new species was found under leaf litter, especially near rocks and in shallow soil.(AU)
Assuntos
Animais , Gastrópodes/classificação , Exoesqueleto/anatomia & histologia , Brasil , Tamanho CorporalResumo
The introduction of the African snail Lissachatina fulica worldwide poses a risk to the environment, agriculture and human health. Considered a socio-environmental pest it causes problems to plantations and gardens, in addition to threatening native species. Also, it can be an intermediate host of worms that affect humans and mammals. This work aims to evaluate the socioenvironmental impact caused by L. fulica in Alto Paraíso de Goiás, Goiás, Brazil. Specifically, it aimed to analyze the residents' knowledge about L. fulica, if they were able to recognize the invasive snail and differentiate it from the giant native snail Megalobulimus sp., in addition to the community's ability to carry out actions to combat the invasive species. Semi-structured interviews were conducted, guided by a questionnaire, with the urban population, and an unstructured interview with a health surveillance agent in the municipality. The area of the city was divided into five zones and ten residences were visited in each zone. It was found that the residents most affected by L. fulica are those who live in the most urbanized region of the city, with 86% of respondents reporting seeing the animal in the city center. The presence of the Megalobulimus sp. was reported by four residents in the city's border regions with the native Cerrado. Most of the reports of the African snail in the houses occurred by residents of Alto Paraíso de Goiás who had plants in their backyard and personally took care of them.(AU)
Assuntos
Humanos , Animais , Caramujos , Meio Ambiente , Indicadores de Impacto Social , Espécies Introduzidas/estatística & dados numéricos , Brasil , Controle de Pragas , Entrevista , PradariaResumo
Background: Conopeptides from cone snail venom have aroused great interest related to the discovery of novel bioactive candidates, due to their excellent prospects for the treatment of various health problems such as pain, addiction, psychosis and epilepsy. In order to explore novel biopeptides, we investigated the structure and function of five novel conopeptides isolated from the venom of Conus marmoreus from South China Sea. Methods: C. marmoreus crude venom was prepared, fractionated and purified by HPLC system. The primary sequences of the five novel disulfide-poor conopeptides Mr-1 to Mr-5 were identified by comprehensive analysis of de novo MALDI-TOF tandem mass spectrometry and Edman degradation data. In order to investigate their function, these five conopeptides were synthesized by Fmoc-SPPS chemistry, and their biological effects at several heterologous rat nicotinic acetylcholine receptor (nAChR) subtypes (α1β1δε, α3β2, α3β4, α4β2) were determined by electrophysiological technique. Results: Five novel disulfide-poor conopeptides were identified and named as follows: Mr-1 (DWEYHAHPKPNSFWT), Mr-2 (YPTRAYPSNKFG), Mr-3 (NVIQAPAQSVAPP NTST), Mr-4 [KENVLNKLKSK(L/I)] and Mr-5 [NAVAAAN(L/I)PG(L/I)V]. None of them contains a disulfide bond. The sequences of conopeptides Mr-2 to Mr-5 do not belong to any category of the known disulfide-poor conopeptides. No significant activity against the above nAChR subtypes were observed for the five conopeptides at 100 µM. Conclusion: We purified and structurally characterized five novel disulfide-poor conopeptides from C. marmoreus crude venom and first investigated their nAChR inhibitory effects. This work expanded our knowledge on the structure and function of disulfide-poor conopeptides from this cone snail venom.(AU)
Assuntos
Animais , Conotoxinas/isolamento & purificação , Dissulfetos/efeitos adversos , Venenos de Moluscos , Espectrometria de MassasResumo
Abstract Megalobulimus dryades sp. nov. is described from the Atlantic Forest in the Vale do Ribeira region, in the states of Paraná and São Paulo, S-SE Brazil, based on morphology. Representatives of the new species with white peristome and glossy periostracum have been misidentified as Megalobulimus gummatus (Hidalgo, 1870) since the 19th Century. The true M. gummatus is revised and redescribed, and its distribution is here restricted to Rio de Janeiro state. Externally, the new species differs from M. gummatus in having distinct protoconch color and sculpture, teleoconch sculpture marked by strong anastomosing rugosities and malleations, and lighter colored white-greyish head-foot. Internally, it presents distinct jaw and radular features, a talon, and a long convoluted penis bearing two flagella. Additional comparisons with other Brazilian congeneric species are also provided.
Resumo
Abstract Megalobulimus dryades sp. nov. is described from the Atlantic Forest in the Vale do Ribeira region, in the states of Paraná and São Paulo, S-SE Brazil, based on morphology. Representatives of the new species with white peristome and glossy periostracum have been misidentified as Megalobulimus gummatus (Hidalgo, 1870) since the 19th Century. The true M. gummatus is revised and redescribed, and its distribution is here restricted to Rio de Janeiro state. Externally, the new species differs from M. gummatus in having distinct protoconch color and sculpture, teleoconch sculpture marked by strong anastomosing rugosities and malleations, and lighter colored white-greyish head-foot. Internally, it presents distinct jaw and radular features, a talon, and a long convoluted penis bearing two flagella. Additional comparisons with other Brazilian congeneric species are also provided.
Resumo
Diverse and unique bioactive neurotoxins known as conopeptides or conotoxins are produced by venomous marine cone snails. Currently, these small and stable molecules are of great importance as research tools and platforms for discovering new drugs and therapeutics. Therefore, the characterization of Conus venom is of great significance, especially for poorly studied species. Methods: In this study, we used bioanalytical techniques to determine the venom profile and emphasize the functional composition of conopeptides in Conus taeniatus, a neglected worm-hunting cone snail. Results: The proteomic analysis revealed that 84.0% of the venom proteins were between 500 and 4,000 Da, and 16.0% were > 4,000 Da. In C. taeniatus venom, 234 peptide fragments were identified and classified as conotoxin precursors or non-conotoxin proteins. In this process, 153 conotoxin precursors were identified and matched to 23 conotoxin precursors and hormone superfamilies. Notably, the four conotoxin superfamilies T (22.87%), O1 (17.65%), M (13.1%) and O2 (9.8%) were the most abundant peptides in C. taeniatus venom, accounting for 63.40% of the total conotoxin diversity. On the other hand, 48 non-conotoxin proteins were identified in the venom of C. taeniatus. Moreover, several possibly biologically active peptide matches were identified, and putative applications of the peptides were assigned. Conclusion: Our study showed that the composition of the C. taeniatus-derived proteome is comparable to that of other Conus species and contains an effective mix of toxins, ionic channel inhibitors and antimicrobials. Additionally, it provides a guidepost for identifying novel conopeptides from the venom of C. taeniatus and discovering conopeptides of potential pharmaceutical importance.(AU)
Assuntos
Animais , Proteoma , Conotoxinas , Caramujo Conus , Venenos de Moluscos , Neurotoxinas , Produtos BiológicosResumo
Megalobulimus dryadessp. nov. is described from the Atlantic Forest in the Vale do Ribeira region, in the states of Paraná and São Paulo, S-SE Brazil, based on morphology. Representatives of the new species with white peristome and glossy periostracum have been misidentified as Megalobulimus gummatus (Hidalgo, 1870) since the 19th Century. The true M. gummatus is revised and redescribed, and its distribution is here restricted to Rio de Janeiro state. Externally, the new species differs from M. gummatus in having distinct protoconch color and sculpture, teleoconch sculpture marked by strong anastomosing rugosities and malleations, and lighter colored white-greyish head-foot. Internally, it presents distinct jaw and radular features, a talon, and a long convoluted penis bearing two flagella. Additional comparisons with other Brazilian congeneric species are also provided.(AU)
Assuntos
Animais , Gastrópodes/classificação , Gastrópodes/genética , Gastrópodes/anatomia & histologia , Exoesqueleto/anatomia & histologiaResumo
Diverse and unique bioactive neurotoxins known as conopeptides or conotoxins are produced by venomous marine cone snails. Currently, these small and stable molecules are of great importance as research tools and platforms for discovering new drugs and therapeutics. Therefore, the characterization of Conus venom is of great significance, especially for poorly studied species. Methods: In this study, we used bioanalytical techniques to determine the venom profile and emphasize the functional composition of conopeptides in Conus taeniatus, a neglected worm-hunting cone snail. Results: The proteomic analysis revealed that 84.0% of the venom proteins were between 500 and 4,000 Da, and 16.0% were > 4,000 Da. In C. taeniatus venom, 234 peptide fragments were identified and classified as conotoxin precursors or non-conotoxin proteins. In this process, 153 conotoxin precursors were identified and matched to 23 conotoxin precursors and hormone superfamilies. Notably, the four conotoxin superfamilies T (22.87%), O1 (17.65%), M (13.1%) and O2 (9.8%) were the most abundant peptides in C. taeniatus venom, accounting for 63.40% of the total conotoxin diversity. On the other hand, 48 non-conotoxin proteins were identified in the venom of C. taeniatus. Moreover, several possibly biologically active peptide matches were identified, and putative applications of the peptides were assigned. Conclusion: Our study showed that the composition of the C. taeniatus-derived proteome is comparable to that of other Conus species and contains an effective mix of toxins, ionic channel inhibitors and antimicrobials. Additionally, it provides a guidepost for identifying novel conopeptides from the venom of C. taeniatus and discovering conopeptides of potential pharmaceutical importance.(AU)
Assuntos
Animais , Proteoma , Conotoxinas , Caramujo Conus , Venenos de Moluscos , Neurotoxinas , Produtos BiológicosResumo
Abstract Background: Diverse and unique bioactive neurotoxins known as conopeptides or conotoxins are produced by venomous marine cone snails. Currently, these small and stable molecules are of great importance as research tools and platforms for discovering new drugs and therapeutics. Therefore, the characterization of Conus venom is of great significance, especially for poorly studied species. Methods: In this study, we used bioanalytical techniques to determine the venom profile and emphasize the functional composition of conopeptides in Conus taeniatus, a neglected worm-hunting cone snail. Results: The proteomic analysis revealed that 84.0% of the venom proteins were between 500 and 4,000 Da, and 16.0% were > 4,000 Da. In C. taeniatus venom, 234 peptide fragments were identified and classified as conotoxin precursors or non-conotoxin proteins. In this process, 153 conotoxin precursors were identified and matched to 23 conotoxin precursors and hormone superfamilies. Notably, the four conotoxin superfamilies T (22.87%), O1 (17.65%), M (13.1%) and O2 (9.8%) were the most abundant peptides in C. taeniatus venom, accounting for 63.40% of the total conotoxin diversity. On the other hand, 48 non-conotoxin proteins were identified in the venom of C. taeniatus. Moreover, several possibly biologically active peptide matches were identified, and putative applications of the peptides were assigned. Conclusion: Our study showed that the composition of the C. taeniatus-derived proteome is comparable to that of other Conus species and contains an effective mix of toxins, ionic channel inhibitors and antimicrobials. Additionally, it provides a guidepost for identifying novel conopeptides from the venom of C. taeniatus and discovering conopeptides of potential pharmaceutical importance.
Resumo
Conopeptides are neuropharmacological peptides derived from the venomous salivary glands of cone snails. Among 29 superfamilies based on conserved signal sequences, T-superfamily conotoxins, which belong to the smallest group, include four different frameworks that contain four cysteines denominated I, V, X and XVI. In this work, the primary structure and the cysteine connectivity of novel conotoxin of Conus bandanus were determined by tandem mass spectrometry using collision-induced dissociation. Methods: The venom glands of C. bandanus snails were dissected, pooled, and extracted with 0.1% trifluoroacetic acid in three steps and lyophilized. The venom was fractionated and purified in an HPLC system with an analytical reversed-phase C18 column. The primary peptide structure was analyzed by MALDI TOF MS/MS using collision-induced dissociation and confirmed by Edman's degradation. The peptide's cysteine connectivity was determined by rapid partial reduction-alkylation technique. Results: The novel conotoxin, NGC1C2(I/L)VREC3C4, was firstly derived from de novo sequencing by MS/MS. The presence of isoleucine residues in this conotoxin was confirmed by the Edman degradation method. The conotoxin, denominated Bn5a, belongs to the T1-subfamily of conotoxins. However, the disulfide bonds (C1-C4/C2-C3) of Bn5a were not the same as found in other T1-subfamily conopeptides but shared common connectivities with T2-subfamily conotoxins. The T1-conotoxin of C. bandanus proved the complexity of the disulfide bond pattern of conopeptides. The homological analysis revealed that the novel conotoxin could serve as a valuable probe compound for the human-nervous-system norepinephrine transporter. Conclusion: We identified the first T1-conotoxin, denominated Bn5a, isolated from C. bandanus venom. However, Bn5a conotoxin exhibited unique C1-C4/C2-C3 disulfide connectivity, unlike other T1-conotoxins (C1-C3/C2-C4). The structural and homological analyses herein have evidenced novel conotoxin Bn5a that may require further investigation.(AU)
Assuntos
Animais , Peptídeos , Conotoxinas , Dissulfetos , Caramujo Conus , Glândulas SalivaresResumo
Background: Conopeptides are neuropharmacological peptides derived from the venomous salivary glands of cone snails. Among 29 superfamilies based on conserved signal sequences, T-superfamily conotoxins, which belong to the smallest group, include four different frameworks that contain four cysteines denominated I, V, X and XVI. In this work, the primary structure and the cysteine connectivity of novel conotoxin of Conus bandanus were determined by tandem mass spectrometry using collision-induced dissociation. Methods: The venom glands of C. bandanus snails were dissected, pooled, and extracted with 0.1% trifluoroacetic acid in three steps and lyophilized. The venom was fractionated and purified in an HPLC system with an analytical reversed-phase C18 column. The primary peptide structure was analyzed by MALDI TOF MS/MS using collision-induced dissociation and confirmed by Edman's degradation. The peptides cysteine connectivity was determined by rapid partial reduction-alkylation technique. Results: The novel conotoxin, NGC1C2(I/L)VREC3C4, was firstly derived from de novo sequencing by MS/MS. The presence of isoleucine residues in this conotoxin was confirmed by the Edman degradation method. The conotoxin, denominated Bn5a, belongs to the T1-subfamily of conotoxins. However, the disulfide bonds (C1-C4/C2-C3) of Bn5a were not the same as found in other T1-subfamily conopeptides but shared common connectivities with T2-subfamily conotoxins. The T1-conotoxin of C. bandanus proved the complexity of the disulfide bond pattern of conopeptides. The homological analysis revealed that the novel conotoxin could serve as a valuable probe compound for the human-nervous-system norepinephrine transporter. Conclusion: We identified the first T1-conotoxin, denominated Bn5a, isolated from C. bandanus venom. However, Bn5a...(AU)
Assuntos
Animais , Venenos de Moluscos/análise , Venenos de Moluscos/química , Dissulfetos/análise , Conotoxinas/isolamento & purificação , Caramujo Conus/patogenicidadeResumo
Achatina fulica snails cause environmental problems and represent a public health hazard since it is a host in the life cycles of various parasites, among them, Angiostrongylus cantonensis and, less frequently, Ancylostoma caninum. We report the occurrence of Angistrongylus cantonensis, as well as the unexpected finding of Ancylostoma caninum, in a total of 936 specimens of Achatina fulica snails from different regions of São Paulo city, Brazil. Samples were divided into 492 pools which were screened for nematodes. If present, larvae were submitted to DNA extraction and PCR protocol targeting, the ITS-2 gene junction. From the 183 positive pools for larvae presence, 97 showed specific 650 bp band at electrophoresis and 21 presented bands nearly 300 bp. Two amplicons from each size were and sequenced. A BLAST/n of 650 bp sequences presented identity with Angistrongylus cantonensis, while the two of 300 bp, showed identity with Ancylostoma caninum, also supported by phylogenetic analysis. This is the second report of Ancylostoma caninum found in these snails in the world, therefore, this study allows a better understanding about these diseases and highlights the need of continue systematically mapping sites that can be infested with the mollusc.
Os caramujos Achatina fulica causam problemas ambientais e representam um perigo em Saúde Pública uma vez que são hospedeiros de vários parasitas, entre eles o Angiostrongylus cantonensis e menos frequentemente o Ancylostoma caninum. Nós relatamos a ocorrência de Angistrongylus cantonensis, bem como o achado de Ancylostoma caninum, a partir de 936 espécimens de caramujos Achatina fulica de diferentes regiões da cidade de São Paulo, Brasil. Amostras foram divididas em 492 pools os quais foram triados para nematóides. Se presentes, larvas foram submetidas a extração de DNA e um protocolo de PCR tendo como alvo a junção do gene ITS-2. De 183 pools contendo larvas, 97 apresentaram bandas específicas de 650 pb e na eletroforese 21 apresentaram bandas próximas aos 300 pb. Dois amplicons de cada tamanho foram sequenciados. A submissão ao BLAST/n das sequências de 650 pb apresentaram identidade das sequências com Angistrongylus cantonensis, enquanto que as duas de 300 pb apresentaram identidade com Ancylostoma caninum, também corroboradas por análises filogenéticas. Este é o segundo relato do encontro de Ancylostoma caninum nestes caramujos no mundo, sendo assim, este estudo permite um melhor entendimento destas doenças e denota a necessidade de contínuo monitoramento de regiões que estejam infestadas pelo molusco.
Assuntos
Animais , Ancylostoma/isolamento & purificação , Angiostrongylus cantonensis/isolamento & purificação , Caramujos/parasitologia , Caramujos/patogenicidade , Espécies Introduzidas/estatística & dados numéricosResumo
Achatina fulica snails cause environmental problems and represent a public health hazard since it is a host in the life cycles of various parasites, among them, Angiostrongylus cantonensis and, less frequently, Ancylostoma caninum. We report the occurrence of Angistrongylus cantonensis, as well as the unexpected finding of Ancylostoma caninum, in a total of 936 specimens of Achatina fulica snails from different regions of São Paulo city, Brazil. Samples were divided into 492 pools which were screened for nematodes. If present, larvae were submitted to DNA extraction and PCR protocol targeting, the ITS-2 gene junction. From the 183 positive pools for larvae presence, 97 showed specific 650 bp band at electrophoresis and 21 presented bands nearly 300 bp. Two amplicons from each size were and sequenced. A BLAST/n of 650 bp sequences presented identity with Angistrongylus cantonensis, while the two of 300 bp, showed identity with Ancylostoma caninum, also supported by phylogenetic analysis. This is the second report of Ancylostoma caninum found in these snails in the world, therefore, this study allows a better understanding about these diseases and highlights the need of continue systematically mapping sites that can be infested with the mollusc.(AU)
Os caramujos Achatina fulica causam problemas ambientais e representam um perigo em Saúde Pública uma vez que são hospedeiros de vários parasitas, entre eles o Angiostrongylus cantonensis e menos frequentemente o Ancylostoma caninum. Nós relatamos a ocorrência de Angistrongylus cantonensis, bem como o achado de Ancylostoma caninum, a partir de 936 espécimens de caramujos Achatina fulica de diferentes regiões da cidade de São Paulo, Brasil. Amostras foram divididas em 492 pools os quais foram triados para nematóides. Se presentes, larvas foram submetidas a extração de DNA e um protocolo de PCR tendo como alvo a junção do gene ITS-2. De 183 pools contendo larvas, 97 apresentaram bandas específicas de 650 pb e na eletroforese 21 apresentaram bandas próximas aos 300 pb. Dois amplicons de cada tamanho foram sequenciados. A submissão ao BLAST/n das sequências de 650 pb apresentaram identidade das sequências com Angistrongylus cantonensis, enquanto que as duas de 300 pb apresentaram identidade com Ancylostoma caninum, também corroboradas por análises filogenéticas. Este é o segundo relato do encontro de Ancylostoma caninum nestes caramujos no mundo, sendo assim, este estudo permite um melhor entendimento destas doenças e denota a necessidade de contínuo monitoramento de regiões que estejam infestadas pelo molusco.(AU)
Assuntos
Animais , Caramujos/parasitologia , Caramujos/patogenicidade , Angiostrongylus cantonensis/isolamento & purificação , Ancylostoma/isolamento & purificação , Espécies Introduzidas/estatística & dados numéricosResumo
This work aimed to assessing Strongyluris sp. cysts distribution pattern in the several inner organs from pallial system of Achatina fulica Bowdich, 1822. Also we verified if there is a relationship between the mollusk size and the number of specimens from parasites collected from two touristic villages in Ilha Grande (Angra dos Reis, Rio de Janeiro state): Vila Dois Rios (VDR) and Vila do Abraão (ABR). The samples were obtained through a field work conducted bimonthly during 2007, 2008, 2010, and 2011, at both locations. Height and width were measured from shells collected, and the all specimens were classified in different classes: class 1 - 4.0 cm, class 2 - 4.1-9.0 cm and class 3 - 9.0 cm. After the specimens were dissected in order to find and count the number cysts in the pallial system. In specimens from both locations, the pulmonary and secondary veins showed a high number of cysts. No significance difference was found both in the abundance of cysts among the specimens in ABR (p=0.138) and VDR (p=0.181). Achatina fulica showed different intensities of cyst infection based on the size classes: the class-3 specimens, at both locations, showed the greatest cyst average (ABR Anova F= 3.8; p=0.02); (VDR T of Student T= -2.04; p=0.04). The results suggested that the highest number of cysts in the vascularized area in pallial system of A. fulica was a consequence of a greater hemolymph circulation in that area, delivering more nutrients for larvae development. We think that bigger individuals host a higher number of cysts, as they usually present a larger biomass and a larger area of the pallial system, allowing an efficient parasite colonization. Other possible explanation could be the long exposure of the molluscs of class 3 to the parasites, which allowed a longer time to the larvae to allocate themselves.(AU)
O objetivo do estudo foi analisar o padrão de distribuição dos cistos de Strongyluris sp. nos diversos órgãos do complexo pallial de Achatina fulica Bowdich, 1822 e verificar se existe relação entre o tamanho do molusco e o número de parasitos em espécimes procedentes de dois vilarejos da Ilha Grande, Vila Dois Rios (VDR) e Vila do Abraão (ABR), município de Angra dos Reis, Rio de Janeiro. As coletas foram realizadas bimestralmente nos anos de 2007, 2008, 2010 e 2011 nas duas localidades. A altura e largura das conchas foram medidas, os espécimes classificados em classe 1 - 4,0 cm; classe 2 - 4,1-9,0 cm e classe 3 - 9,0 cm e posteriormente dissecados sob estereomicroscópio para a busca e contagem dos cistos no complexo pallial. Em ambas localidades, VDR e ABR, as veias pulmonares e secundárias apresentaram predominância de alocação dos cistos. Não foi encontrada diferença na abundância de cistos entre os espécimes de ABR (p=0,138) e VDR (p=0,181). Achatina fulica apresentou intensidades diferentes de infecção de acordo com as classes de tamanho: os espécimes pertencentes a classe 3, nas duas localidades, apresentaram a maior média de cistos visíveis (ABR Anova F= 3,8; p=0,02); (VDR T de Student T= -2,04; p=0,04). Os resultados sugerem que o maior número de cistos na região vascularizada de A. fulica foi decorrente do maior aporte de hemolinfa nesta área, proporcionando mais nutrientes para o desenvolvimento das larvas. Acreditamos que indivíduos maiores albergam um elevado número de cistos, pois, geralmente, apresentam maior biomassa e maior área da cavidade pallial, possibilitando uma eficiente colonização dos parasitos, outra causa pode ser explicada pelo maior tempo de exposição dos moluscos da classe 3 aos parasitas, que possibilitou um período maior para as larvas se alocarem.(AU)
Resumo
Since the foundation of the Malacological Center in 1980, Universidad Centro Americana (UCA), Managua-Nicaragua, has been monitoring and collecting the marine, terrestrial, fluvial and lake mollusk population of the country. Many specimens have been photographed by Scanning Electronic Microscope (SEM), and in one of these, observation of the hairy periostracum reveals a seemingly thriving population of minute protists in possible symbiosis with their host. Adequate magnification and comparison with previous studies allowed the determination of these hosts as diatoms, testaceous amoebae, yeast, phacus, spores and other undetermined organisms which occur in tropical forests on rocks, trees and leaves. Here illustrated are diatoms and other organisms detected for the first time on the periostracum of a tropical rainforest mollusk.(AU)
Desde a fundação do Centro Malacológico em 1980, a Universidad Central Americana (UCA), Manágua-Nicarágua, vem acompanhando e coletando a população de moluscos marinhos, terrestres, fluviais e lagoas do país. Muitos espécimes foram fotografados pelo microscópio eletrônico de varredura (SEM) e, em um deles, a observação do periostracum peludo revela uma população aparentemente próspera de protistas de minuto em possível simbiose com o hospedeiro. A ampliação adequada e a comparação com estudos anteriores permitem a determinação dessas diatomáceas, amebas testaceas, leveduras, phacus, esporos e outros organismos indeterminados que ocorrem em florestas tropicais em rochas, árvores e folhas. Aqui estão as diatomeas e outros organismos pela primeira vez detectados no periostracum de um molusco tropical.(AU)