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1.
Braz. j. biol ; 83: e248420, 2023. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1339367

RESUMO

Abstract Very little is known about the malacofauna in district Swat of Khyber Pakhtunkhwa province, situated in the Northern part of Pakistan. The Swat valley possesses a variety of suitable environmental conditions, providing different types of habitats for both flora and fauna. Taken into consideration these points, the present study was conducted to explore the terrestrial snails diversity in agricultural and non-agricultural fields in the lower Swat valley. A total of 417 shells were collected from three sites: Kokarai, Kanju Township, and Deolai. Based on conchological features, three families: Bradybaenidae, Hygromiidae, and Zonitidae were identified using different terrestrial snail keys. In Kokarai and Deolai, shells of members of all the above-mentioned families were found from agricultural fields. In Kanju Township, shells of members of the family Bradybaenidae and Zonitidae were found. From these findings, it was concluded that district Swat possesses a significant malacofauna which was unexplored before and aided more to the existing literature on malacofauna. It also supports the idea that the agroecosystem is rich in species diversity. Further in-depth and extensive study is recommended to be carried out for a detailed taxonomy of the described terrestrial gastropod families.


Resumo Muito pouco se sabe sobre a malacofauna no distrito de Swat, na província de Khyber Pakhtunkhwa, situada na parte norte do Paquistão. O vale do Swat possui uma variedade de condições ambientais adequadas, proporcionando diferentes tipos de habitats para a flora e a fauna. Levando em consideração esses pontos, o presente estudo foi conduzido para explorar a diversidade dos caracóis terrestres em campos agrícolas e não agrícolas no vale inferior de Swat. Um total de 417 conchas foram coletadas em três locais: Kokarai, Kanju Township e Deolai. Com base em características concológicas, três famílias: Bradybaenidae, Hygromiidae e Zonitidae foram identificadas usando diferentes chaves de caramujos terrestres. Em Kokarai e Deolai, conchas de membros de todas as famílias mencionadas acima foram encontradas em campos agrícolas. No município de Kanju, foram encontradas conchas de membros da família Bradybaenidae e Zonitidae. A partir dessas constatações, concluiu-se que o distrito de Swat possui uma malacofauna significativa que antes era inexplorada e ajudava mais a literatura existente sobre a malacofauna. Também apoia a ideia de que o agroecossistema é rico em diversidade de espécies. Recomenda-se a realização de um estudo mais aprofundado e extenso para uma taxonomia detalhada das famílias de gastrópodes terrestres descritas.


Assuntos
Humanos , Animais , Ecossistema , Agricultura , Paquistão , Caramujos
2.
Braz. j. biol ; 83: e246934, 2023. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1285605

RESUMO

Abstract Physids belong to Class Gastropoda; Phylum Mollusca have important position in food web and act as bio indicators, pests and intermediate host. Being resistant these are called cockroaches of malacology. Physid snails were collected from different water bodies of Faisalabad (Punjab) and were identified up to species using morphological markers. The morphometry of the specimens was carried out with the help of a digital Vernier caliper in millimeters (mm) using linear measurement of shell characters. Linear regression analysis of the AL/SW ratio vs AL and SL/SW ratio vs AL indicated that allometric growth exists only in Physa acuta when compared with P.gyrina and P. fontinalis. This study will lead to assess the status of the Physid species in Central Punjab. The Principal component analysis shows that the Component 1 (Shell Length) and component 2 (Shell Width) are the most prolific components and nearly 80 percent of the identification. The distance between P. acuta and P. fontinalis is 5.4699, P. acuta and P. gyrina is 7.6411, P. fontinalis and P. gyrina is 16.6080 showing that P. acuta resembles with P. fontinalis, and both these specimens donot resemble with P. gyrina. P.acuta is an invasive species and shows bioactivity making it a potent candidate for bioactive substances.


Resumo Os físidos pertencem à classe Gastropoda; o filo Mollusca possui importante posição na teia alimentar e atua como bioindicador, praga e hospedeiro intermediário. Por serem resistentes, são chamadas baratas de malacologia. Os caramujos físidos foram coletados em diferentes corpos d'água de Faisalabad (Punjab) e identificados até as espécies por meio de marcadores morfológicos. A morfometria dos corpos de prova foi realizada com auxílio de paquímetro digital Vernier em milímetros (mm) por meio de medida linear dos caracteres da casca. A análise de regressão linear da razão AL / SW vs. AL e razão SL / SW vs. AL indicou que o crescimento alométrico existe apenas em Physa acuta quando comparado com P. gyrina e P. fontinalis. Este estudo levará a avaliar a situação das espécies de físido no Punjab Central. A análise do componente principal mostra que o componente 1 (comprimento da casca) e o componente 2 (largura da casca) são os componentes mais prolíficos e quase 80% da identificação. A distância entre P. acuta e P. fontinalis é 5,4699, P. acuta e P. gyrina é 7,6411, P. fontinalis e P. gyrina é 16,6080, mostrando que P. acuta se assemelha a P. fontinalis, e ambos os espécimes não se parecem com P. gyrina. P. acuta é uma espécie invasora e apresenta bioatividade, tornando-se uma candidata potente para substâncias bioativas.


Assuntos
Animais , Caramujos , Espécies Introduzidas
3.
Braz. j. biol ; 83: e243801, 2023. graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1278545

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 Demográfica
4.
Sci Rep ; 12(1): 8549, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35595826

RESUMO

Multi-elemental analysis is widely used to identify the geographical origins of plants. The purpose of this study was to explore the feasibility of combining chemometrics with multi-element analysis for classification of Codonopsis Radix from different producing regions of Gansu province (China). A total of 117 Codonopsis Radix samples from 7 counties of Gansu province were collected. Inductively coupled plasma mass spectrometry (ICP-MS) was used for the determination of 28 elements (39 K, 24 Mg, 44Ca, 27Al, 137Ba, 57Fe, 23Na, 88Sr, 55Mn, 66Zn, 65Cu, 85Rb, 61Ni, 53Cr, 51 V, 7Li, 208Pb, 59Co, 75As, 133Cs, 71 Ga, 77Se, 205Tl, 114Cd, 238U, 107Ag, 4Be and 202Hg). Among macro elements, 39 K showed the highest level, whereas 23Na was found to have the lowest content value. Micro elements showed the concentrations order of: 88Sr > 55Mn > 66Zn > 85Rb > 65Cu. Among trace elements, 53Cr and 61Ni showed higher content and 4Be was not detected in all samples. Intra-regions differentiation was performed by principal component analysis (PCA), cluster analysis (CA) and supervised learning algorithms such as linear discriminant analysis (LDA), k-nearest neighbors (k-NN), support vector machines (SVM), and random forests (RF). Among them, the RF model performed the best with an accuracy rate of 78.79%. Multi-elemental analysis combined with RF was a reliable method to identify the origins of Codonopsis Radix in Gansu province.


Assuntos
Codonopsis , Oligoelementos , China , Análise Discriminante , Caramujos , Oligoelementos/análise
5.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 34(2): 122-127, 2022 Apr 15.
Artigo em Chinês | MEDLINE | ID: mdl-35537833

RESUMO

OBJECTIVE: To analyze the trends of human schistosomiasis prevalence in Hubei Province from 2004 to 2018, so as to provide the evidence for formulating the schistosomiasis elimination strategy in the province. METHODS: All data pertaining to human schistosomiasis prevalence in Hubei Province were collected from 2004 to 2018, and the trends for changes in seroprevalence, egg-positive rate and prevalence of human Schistosoma japonicum infection were analyzed using a Joinpoint regression model. RESULTS: Both of the numbers of residents seropositive and egg-positive for S. japonicum infections appeared a tendency towards a decline in Hubei Province from 2004 to 2018, and the prevalence of human S. japonicum infections reduced from 6.85% in 2004 to 0 in 2018. Joinpoint regression analysis showed that the prevalence of human S. japonicum infections appeared an overall tendency towards a reduction in Hubei Province from 2004 to 2018 [average annual percent change (AAPC) = -24.1%, P < 0.01], and the trends for the reduction were both significant during the period from 2004 to 2006 [annual percent change (APC) = -35.1%, P < 0.01] and from 2006 to 2018 (APC = -22.1%, P < 0.01). The prevalence of human S. japonicum infections appeared a tendency towards a decline in islet (AAPC = -25.1%, P < 0.01), inner embankment (AAPC = -26.4%, P < 0.01) and hilly subtypes of schistosomiasis-endemic areas (AAPC = -32.5%, P < 0.01) of Hubei Province from 2004 to 2018, and the prevalence all appeared a tendency towards a decline during the infection control stage (from 2004 to 2008), the transmission control stage (from 2009 to 2013) and the transmission interruption stage (from 2014 to 2018) (AAPC = -28.0%, -24.4% and -63.8%, all P values < 0.01). The seroprevalence of human S. japonicum infections appeared an overall tendency towards a decline in Hubei Province from 2004 to 2018 (AAPC = -14.5%, P < 0.01), and the trends for the reduction were both significant during the period from 2004 to 2012 (APC = -8.4%, P < 0.01) and from 2012 to 2018 (APC = -22.1%, P < 0.01). In addition, the egg-positive rate of human S. japonicum infections appeared an overall tendency towards a decline in Hubei Province from 2004 to 2018 (AAPC = -30.6%, P < 0.05), and the trend for the reduction was significant during the period from 2007 to 2014 (APC = -15.5%, P < 0.01). CONCLUSIONS: The prevalence of human schistosomiasis appeared a tendency towards a decline in Hubei Province from 2004 to 2018, and the islet and inner embankment subtypes of endemic areas are a high priority for schistosomiasis control during the stage moving towards elimination in Hubei Province.


Assuntos
Esquistossomose Japônica , Esquistossomose , Animais , China/epidemiologia , Humanos , Prevalência , Análise de Regressão , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Esquistossomose Japônica/epidemiologia , Estudos Soroepidemiológicos , Caramujos
6.
Front Immunol ; 13: 878783, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35515005

RESUMO

Nematodes and bacteria are prevalent in soil ecosystems, and some have evolved symbiotic relationships. In some cases, symbionts carry out highly specialized functions: a prime example being entomopathogenic nematodes (EPNs), which vector bacteria (Xenorhabdus or Photorhabdus) into insect hosts, killing them to provide a food source for the nematodes. It is thought that the commercially available malacopathogenic (kills slugs and snails) biocontrol nematode Phasmarhabditis hermaphrodita vectors a bacterium (Moraxella osloensis) into slugs to kill them. To investigate this further we used a metagenomic approach to profile the bacteria present in the commercial strain of P. hermaphrodita, a wild strain of P. hermaphrodita and two other Phasmarhabditis species (P. californica and P. neopapillosa), after they had killed their slug host (Deroceras invadens). We show that these nematodes do not exclusively associate with one bacterium but a range of species, with members of the phyla Pseudomonadota, Bacillota, Actinobacteriota and Bacteroidota the most prevalent. The commercial strain of P. hermaphrodita had the least diverse bacterial community. Furthermore, we found that the bacterium P. hermaphrodita has been cultured on for 25 years is not the expected species M. osloensis but is Psychrobacter spp. and the only strain of the Phasmarhabditis species to associate with Psychrobacter spp. was the commercial strain of P. hermaphrodita. In summary, we found no evidence to show that P. hermaphrodita rely exclusively on one bacterium to cause host mortality but found variable and diverse bacterial communities associated with these nematodes in their slug hosts.


Assuntos
Microbiota , Nematoides , Rhabditoidea , Animais , Rhabditoidea/microbiologia , Caramujos , Solo
7.
Arch Environ Contam Toxicol ; 82(4): 520-538, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35441861

RESUMO

The effects of multigenerational Cu exposure on the freshwater gastropod Isidorella newcombi were investigated. Snails were exposed to a range of treatment-specific Cu concentrations in the parental to F2 generations, and a common Cu concentration in the F3 generation. In the parental to F2 generations, some general responses to 3 days Cu exposures included reduced survival and feeding in snails exposed to higher Cu concentrations. This suggested that the snails exposed to the high Cu concentration were experiencing Cu-induced stress that may apply selection pressure. In the F3 generation, when all treatments were exposed to a common Cu concentration, increased survival was correlated with the pre-exposure Cu concentration history. Snails that had been pre-exposed to Cu also displayed reduced stress at a sub-lethal level, indicated by lower lysosomal destabilisation (LD). Mortality and LD responses in the F3 generation were not related to Cu tissue concentrations, indicating increased tolerance and reduced stress were not related to changes in Cu bioaccumulation. Total antioxidant capacity increased in the higher Cu concentration pre-exposure treatments which could be associated with lower Cu-induced stress, however, this is not supported by the oxidative damage marker lipid peroxidation, which also increased. While Cu tissue concentrations and oxidative stress markers were assessed to determine underlying reasons for increased tolerance in snails from a population with a multi-generational exposure history to Cu, the results were not conclusive. Despite this, it was demonstrated through increased survival and reduced LD that Cu tolerance can develop over a short evolutionary time scale.


Assuntos
Cobre , Poluentes Químicos da Água , Animais , Biomarcadores , Cobre/análise , Cobre/toxicidade , Água Doce , Estresse Oxidativo , Caramujos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
8.
Physiol Biochem Zool ; 95(3): 251-264, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35443148

RESUMO

AbstractUnderstanding the physiology of invasive species will contribute to better prediction and prevention measures to avoid the economic and environmental consequences of biological invasions. Predicting the future range of Potamopyrgus antipodarum, a globally invasive aquatic snail, relies on a comprehensive understanding of its physiological tolerances to individual and combined environmental stressors. We conducted a laboratory study to investigate the interacting effects of temperature and dissolved oxygen in shaping the abiotic niche of P. antipodarum. We generated thermal performance curves (7°C-35°C) for resting respiration rate and voluntary locomotor behaviors under normoxia and hypoxia to find the conditions that limited each performance. Extreme high (>30°C) and low (<12°C) temperatures limited respiration and activity, but respiration rate was most oxygen sensitive at low temperatures. Under hypoxic conditions, activity was less thermally sensitive. Increased activity under high temperatures (22°C-28°C) may be fueled by anaerobic metabolism. Relying on anaerobic energy is a time-limited survival strategy, so further warming and deoxygenation of freshwater systems may limit the spread of this very tolerant invasive species.


Assuntos
Hipóxia , Caramujos , Animais , Água Doce , Espécies Introduzidas , Locomoção/fisiologia , Oxigênio , Caramujos/fisiologia , Temperatura
9.
Arch Microbiol ; 204(5): 271, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35445346

RESUMO

Schistosoma mansoni is a heteroxenous parasite, meaning that during its life cycle needs the participation of obligatory intermediate and definitive hosts. The larval development occurs in aquatic molluscs belonging to the Biomphalaria genus, leading to the formation of cercariae, which emerge to infect the final vertebrate host. For this reason, studies for control of the diseases caused by digenetic trematodes often focus on combating the snail hosts. Thus, the objective of this study was to evaluate the susceptibility of Biomphalaria tenagophila embryos to the fungus Pochonia chlamydosporia (isolate Pc-10). The entire experiment was conducted in duplicate, with five replicates for each repetition (five egg masses/replicate), utilizing a total of 100 egg masses, with 20-30 eggs/egg mass. At the end of 15 days, the egg masses were evaluated under a stereomicroscope to analyze the hatching of B. tenagophila embryos in both experimental groups. After days of interaction, the exposure to the fungal hyphae bodies significantly impaired the viability of the B. tenagophila eggs, inhibiting the embryogenesis process by 83.7% in relation to the control group. Transmission and scanning electron microscopic images revealed relevant structural alterations in the egg masses exposed to the hyphae action of the fungus, interfering in the development and hatching of the young snails under analysis. These results indicate the susceptibility of B. tenagophila embryos to the fungus P. chlamydosporia (isolate Pc-10) and suggest the potential of Pc-10 to be used in the control of intermediate host, for its ovicidal capacity and for being an ecologically viable option, but in vivo experiments become necessary.


Assuntos
Ascomicetos , Biomphalaria , Animais , Biomphalaria/parasitologia , Interações Hospedeiro-Parasita , Hypocreales , Schistosoma mansoni , Caramujos
10.
Biomedica ; 42(1): 67-84, 2022 03 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35471171

RESUMO

INTRODUCTION: Praziquantel (PZQ) is the only commercially available drug for schistosomiasis. The current shortage of alternative effective drugs and the lack of successful preventive measures enhance its value. The increase in the prevalence of PZQ resistance under sustained drug pressure is, therefore, an upcoming issue. OBJECTIVE: To overcome the tolerance to PZQ using nanotechnology after laboratory induction of a Schistosoma mansoni isolate with reduced sensitivity to the drug during the intramolluscan phase. MATERIALS AND METHODS: Shedding snails were treated with PZQ doses of 200 mg/kg twice/ week followed by an interval of one week and then repeated twice in the same manner. The success of inducing reduced sensitivity was confirmed in vitro via the reduction of cercarial response to PZQ regarding their swimming activity and death percentage at different examination times. RESULTS: Oral treatment with a single PZQ dose of 500 mg/kg in mice infected with cercariae with reduced sensitivity to PZQ revealed a non-significant reduction (35.1%) of total worm burden compared to non-treated control mice. Orally inoculated PZQ-encapsulated niosomes against S. mansoni with reduced sensitivity to PZQ successfully regained the pathogen's sensitivity to PZQ as evidenced by measuring different parameters in comparison to the non-treated infected animals with parasites with reduced sensitivity to PZQ. The mean total worm load was 1.33 ± 0.52 with a statistically significant reduction of 94.09% and complete eradication of male worms. We obtained a remarkable increase in the percentage reduction of tissue egg counts in the liver and intestine (97.68% and 98.56%, respectively) associated with a massive increase in dead eggs and the complete absence of immature stages. CONCLUSION: PZQ-encapsulated niosomes restored the drug sensitivity against laboratory-induced S. mansoni adult worms with reduced sensitivity to PZQ.


Introducción. El prazicuantel es el único fármaco disponible comercialmente para la esquistosomiasis. La escasez actual de medicamentos alternativos y la falta de medidas preventivas eficaces aumentan su valor. La creciente prevalencia de la resistencia al prazicuantel bajo una presión prolongada del fármaco es, por tanto, un tema emergente. Objetivos. Superar la tolerancia al prazicuantel mediante nanotecnología después de la inducción en laboratorio de un aislamiento de Schistosoma mansoni con sensibilidad reducida al fármaco durante la fase intramolusco. Materiales y métodos. Los caracoles que liberaban cercarias se trataron con prazicuantel en dosis de 200 mg/kg dos veces por semana, seguidas de un intervalo de una semana, y luego se repitieron dos veces de la misma manera. La inducción exitosa de la sensibilidad reducida se confirmó in vitro mediante la reducción de la reacción de las cercarias al prazicuantel con respecto a su actividad de natación y el porcentaje de muerte en diferentes momentos de examen. El éxito en inducir una menor sensibilidad se confirmó in vitro mediante la reducción de la reacción de las cercarias al prazicuantel. Resultados. El tratamiento oral con una dosis única de prazicuantel de 500 mg/kg en ratones infectados con cercarias con sensibilidad reducida al prazicuantel, reveló una reducción no significativa (35,1 %) de la carga total de gusanos en comparación con los ratones de control no tratados. Los niosomas encapsulados en prazicuantel inoculados por vía oral contra S. mansoni con sensibilidad reducida al prazicuantel, permitieron reestablecer con éxito la sensibilidad del patógeno al medicamento, como lo demostró la medición de diferentes parámetros en comparación con los animales infectados no tratados con parásitos con sensibilidad reducida a prazicuantel. La carga media total de gusanos fue de 1,33 ± 0,52, con una reducción estadísticamente significativa del 94,09 %, y la erradicación completa de los gusanos machos adultos. Se obtuvo un aumento notable en el porcentaje de reducción del recuento de huevos en el tejido del hígado y el intestino (97,68 % y 98,56 %, respectivamente), asociado con un aumento masivo de huevos muertos y ausencia total de estadios inmaduros. Conclusión. Los niosomas encapsulados en prazicuantel restauraron la sensibilidad al fármaco contra gusanos adultos de S. mansoni con sensibilidad reducida al prazicuantel inducida en el laboratorio.


Assuntos
Praziquantel , Schistosoma mansoni , Animais , Resistência a Medicamentos , Lipossomos/farmacologia , Masculino , Camundongos , Praziquantel/farmacologia , Praziquantel/uso terapêutico , Caramujos
11.
Mar Environ Res ; 177: 105618, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35405423

RESUMO

Tropical species are predicted to be among the most vulnerable to climate change as they often live close to their upper limits to thermal tolerance and in many cases, behavioural thermoregulation is required to persist in the thermal extremes of tropical latitudes. In concert with warming temperatures, near-shore species are faced with the additional threat of shoreline hardening, leading to a reduction in microhabitats that can provide thermal refuges. This situation is exemplified in Singapore, which lies almost on the equator and so experiences year-round hot temperatures, and much of its coastline is now seawall. To investigate the thermal ecology of a common intertidal gastropod, Nerita undata, on these artificial structures, we measured thermal conditions on two seawalls, the temperatures of habitats occupied by the snail, and compared these with the snail's thermal tolerance by measuring heart rate and behavioural thermoregulation (as preferred temperature, Tpref). At one of the two seawalls (Tanjong Rimau), temperatures experienced by N. undata exceeded all measures of thermal tolerance in the sun, while at the other (Palawan Beach), they did not. Temperatures in habitats occupied by the snails on the seawalls were similar to their measured Tpref in the laboratory and were lower than all measures of thermal tolerance. Behavioural thermoregulation by the snails, therefore, significantly increased the thermal safety margins of N. undata on the relatively homogenous seawalls in Singapore, and at one of the two seawalls were necessary to allow snails to survive. Accordingly, to facilitate motile species to maintain broad thermal safety margins through behavioural regulation, the provision of additional refuges from thermal stress is recommended on artificial coastal defences such as seawalls.


Assuntos
Mudança Climática , Caramujos , Animais , Ecossistema , Temperatura Alta , Temperatura
12.
Molecules ; 27(7)2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35408688

RESUMO

Acne vulgaris is a common skin disease mainly caused by the Gram-positive pathogenic bacterium, Propionibacterium acnes. This bacterium stimulates the inflammation process in human sebaceous glands. The giant African snail (Achatina fulica) is an alien species that rapidly reproduces and seriously damages agricultural products in Thailand. There were several research reports on the medical and pharmaceutical benefits of these snail mucus peptides and proteins. This study aimed to in silico predict multifunctional bioactive peptides from A. fulica mucus peptidome using bioinformatic tools for the determination of antimicrobial (iAMPpred), anti-biofilm (dPABBs), cytotoxic (ToxinPred) and cell-membrane-penetrating (CPPpred) peptides. Three candidate peptides with the highest predictive score were selected and re-designed/modified to improve the required activities. Structural and physicochemical properties of six anti-P. acnes (APA) peptide candidates were performed using the PEP-FOLD3 program and the four previous tools. All candidates had a random coiled structure and were named APAP-1 ori, APAP-2 ori, APAP-3 ori, APAP-1 mod, APAP-2 mod, and APAP-3 mod. To validate the APA activity, these peptide candidates were synthesized and tested against six isolates of P. acnes. The modified APA peptides showed high APA activity on three isolates. Therefore, our biomimetic mucus peptides could be useful for preventing acne vulgaris and further examined on other activities important to medical and pharmaceutical applications.


Assuntos
Acne Vulgar , Propionibacterium acnes , Acetaminofen/metabolismo , Acne Vulgar/tratamento farmacológico , Acne Vulgar/microbiologia , Animais , Antibacterianos/química , Humanos , Muco/química , Peptídeos/química , Preparações Farmacêuticas/análise , Propionibacterium acnes/metabolismo , Caramujos/química
13.
Vet Parasitol Reg Stud Reports ; 30: 100707, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35431065

RESUMO

Lymnaeid snails play an essential role in transmitting fasciolosis as intermediate hosts. Therefore, this study aims to use the molecular method to identify liver fluke in lymnaeid snails. A total of 320 lymnaeid snails were collected from a rice field. The samples were dissected to collect cercaria and identified using polymerase chain reaction. Furthermore, the internal transcribed spacer 2 (ITS2) was used as the target gene to identify the species of cercaria. The result showed that 3.75% (12/320) of the snails were infected by Fasciola gigantica, while the phylogenetic tree based on ITS2 showed that the cercaria in this study was monophyletic and similar to species from several countries in Southeast Asia, including China. Furthermore, the haplotype network showed that all four cercaria samples were similar with sequences from several countries. This study suggests that the F. gigantica cercaria isolated from lymnaeid snails in Kulon Progo, Yogyakarta, Indonesia, has a sequence similar to that of other species in Southeast Asian countries, although no hybrid type was detected in these sequences. This is the first report on the molecular identification of cercaria F. gigantica isolated from lymnaeid snails in Yogyakarta, Indonesia.


Assuntos
Fasciola , Fasciolíase , Animais , Cercárias/genética , Fasciola/genética , Fasciolíase/veterinária , Filogenia , Caramujos
14.
Vet Parasitol Reg Stud Reports ; 30: 100712, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35431070

RESUMO

Aelurostrongylus abstrusus is a metastrongilid nematode that causes feline aelurostrongylosis. The adult life stage parasitizes the lungs of wild and domestic felids. Terrestrial mollusks act as its intermediate host, and birds, amphibians, and small mammals act as paratenic hosts. Aelurostrongylus abstrusus presents a worldwide distribution, and in Brazil it has been recorded in most states. The present study investigates the occurrence of Aelurostrongylus abstrusus in terrestrial mollusks from urban areas of two out of the six Mesoregions of Rio de Janeiro state: Metropolitana and Centro Fluminense (46 municipalities). Larvae were recovered from the tissue of the mollusks collected during the surveys and identified based on morphology and sequences of the Internal Transcribed Spacer 2 (ITS2). In all, 2791 mollusks, belonging to 14 different species, were collected. Larvae of A. abstrusus were recovered from two species: Achatina fulica in 22 out of 46 municipalities, and from the slug Latipes erinaceus in 1 out of 46 municipalities. Aelurostrongylus abstrusus was recorded in half (50%) of the municipalities of the Metropolitana Mesoregion and in 44% of those of the Centro Fluminense Mesoregion. Results indicate a strong association between A. abstrusus and A. fulica, since 99% of the mollusks infected with A. abstrusus were A. fulica. This study recorded A. abstrusus in the Centro Fluminense Mesoregion and naturally parasitizing L. erinaceus for the first time. Despite the high number of mollusks infected with A. abstrusus and their wide distribution in Rio de Janeiro State, there are still few reports of infection in Brazilian felids, probably given that this is an under-diagnosed parasitosis in this country. Further studies in other regions of the Rio de Janeiro State, and other Brazilian States, focusing on intermediate and definitive hosts, particularly in the urban environments where they coexist, are needed. These studies will enable further understanding of the epidemiology and prevention of aelurostrongylosis.


Assuntos
Doenças do Gato , Felidae , Metastrongyloidea , Infecções por Strongylida , Animais , Aves , Brasil/epidemiologia , Gatos , Larva , Caramujos , Infecções por Strongylida/epidemiologia , Infecções por Strongylida/veterinária
15.
Ecotoxicol Environ Saf ; 236: 113514, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35427879

RESUMO

The interactions between hyperaccumulators and their associated herbivores have been mostly investigated in their natural habitats and largely ignored in the phytoremediation practice. Herein, we investigated the herbivory status of Zn/Cd-hyperaccumulating plant Sedum alfredii from both their natural habitats and their applied remediation field, and inspected the adaptive strategies of the herbivores from the perspective of their facilitative gut microbiota. Field investigations showed that snail species Bradybaena ravida was the dominant herbivore feeding on S. alfredii and they can be only found in sites with lower levels of heavy metals compared with the plant natural habitat. Gut microbial community was analyzed using two sequencing methods (16S rRNA and czcA-Zn/Cd resistant gene) to comparatively understand the effect of gut microbes in facilitating snail feeding on the hyperaccumulators. The results revealed significant differences in the diversity and richness between the gut microbiota of the two snail populations, which was more pronounced by the czcA sequencing method. Despite of the compositional differences, their functions seemed to converge into three categories as metal-tolerant and contaminant degraders, gut symbionts, and pathogens. Further function potentials predicted by Tax4Fun based on 16 S sequencing data were in accordance with this categorization as the most abundant metabolic pathways were two-component system and ABC transporter, which was closely related to metal stress adaptation. The prevalence of positive interactions (~80%) indicated by the co-occurrence network analysis based on czcA sequencing data in both groups of gut microbiota further suggested the facilitative effect of these metal-tolerant gut microbes in coping with the high metal diet, which ultimately assist the snails to successfully feed on S. alfredii plants and thrive. This work for the first time provides evidence that the herbivore adaptation to hyperaccumulators were also associated with their gut microbial adaptation to metals.


Assuntos
Microbioma Gastrointestinal , Metais Pesados , Sedum , Poluentes do Solo , Animais , Biodegradação Ambiental , Cádmio/metabolismo , Metais Pesados/análise , Raízes de Plantas/metabolismo , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Sedum/metabolismo , Caramujos/genética , Caramujos/metabolismo , Poluentes do Solo/análise
16.
Proc Biol Sci ; 289(1972): 20211855, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35382597

RESUMO

Transitions to terrestriality have been associated with major animal radiations including land snails and slugs in Stylommatophora (>20 000 described species), the most successful lineage of 'pulmonates' (a non-monophyletic assemblage of air-breathing gastropods). However, phylogenomic studies have failed to robustly resolve relationships among traditional pulmonates and affiliated marine lineages that comprise clade Panpulmonata (Mollusca, Gastropoda), especially two key taxa: Sacoglossa, a group including photosynthetic sea slugs, and Siphonarioidea, intertidal limpet-like snails with a non-contractile pneumostome (narrow opening to a vascularized pallial cavity). To clarify the evolutionary history of the panpulmonate radiation, we performed phylogenomic analyses on datasets of up to 1160 nuclear protein-coding genes for 110 gastropods, including 40 new transcriptomes for Sacoglossa and Siphonarioidea. All 18 analyses recovered Sacoglossa as the sister group to a clade we named Pneumopulmonata, within which Siphonarioidea was sister to the remaining lineages in most analyses. Comparative modelling indicated shifts to marginal habitat (estuarine, mangrove and intertidal zones) preceded and accelerated the evolution of a pneumostome, present in the pneumopulmonate ancestor along with a one-sided plicate gill. These findings highlight key intermediate stages in the evolution of air-breathing snails, supporting the hypothesis that adaptation to marginal zones played an important role in major sea-to-land transitions.


Assuntos
Gastrópodes , Animais , Núcleo Celular , Ecossistema , Gastrópodes/genética , Filogenia , Caramujos/genética
17.
Arch Environ Contam Toxicol ; 82(3): 429-438, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35332359

RESUMO

Behavioral endpoints are important parameters to assess the effects of toxicants on aquatic animals. These endpoints are useful in ecotoxicology because several toxicants modify the animal behavior, which may cause adverse effects at higher levels of ecological organization. However, for the development of new bioassays and for including the behavior in ecotoxicological risk assessment, the comparison of sensitivity between different behavioral endpoints is necessary. Additionally, some toxicants remain in aquatic environments for a few hours or days, which may lead to animal recovery after toxicant exposure. Our study aimed to assess the effect of unionized ammonia on the movement and feeding behaviors of the aquatic gastropod Potamopyrgus antipodarum (Tateidae, Mollusca) and its recovery after exposure. Four treatments were used: a control and three nominal concentrations of unionized ammonia (0.25, 0.5 and 1 mg N-NH3/L). Each treatment was replicated eight times, with six animals in each replicate. Animals were exposed to unionized ammonia for 48 h (exposure period) and, subsequently, to control water for 144 h (post-exposure period). Two movement variables were monitored without food and five feeding behavioral variables were monitored in the presence of food. Some of the feeding behavioral variables showed higher sensitivity (LOEC = 0.25-0.5 mg N-NH3/L) than the movement behavior variables monitored without food (LOEC = 1 mg N-NH3/L). After exposure to unionized ammonia, animals showed a recovery of most behavioral endpoints. The inclusion of post-exposure period and feeding behaviors in bioassays may make studies more realistic, which is crucial for a proper ecotoxicological risk assessment.


Assuntos
Amônia , Poluentes Químicos da Água , Amônia/toxicidade , Animais , Bioensaio , Ecotoxicologia , Caramujos , Poluentes Químicos da Água/toxicidade
18.
PLoS One ; 17(3): e0264996, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35286318

RESUMO

Quantifying feeding behaviour of generalist predators at the population and individual levels is crucial for understanding the structure and functioning of food webs. Individual predator/consumer feeding niches can be significantly narrower than that of the population across animal taxa. In such species, the population of a generalist predator becomes essentially an ensemble of specialist individuals and this often highly affects the dynamics of the prey-predator interactions. Currently, few experimental systems exist that are both easily technically manipulated in a lab and are reliable to accurately assess effects of individual specialisation within generalist predators. Here we argue that a freshwater predaceous snail, Anentome helena (also known as an 'assassin snail'), is a convenient and reliable experimental system to study feeding of a generalist predator on multiple food types which exhibits well-pronounced specialisation of foraging individuals. Using A. helena we experimentally test: (i) how relative prey abundances in the environment affect the feeding patterns, (ii) whether the feeding patterns are consistent over the duration of the experimental period, and (iii) compare the feeding niche breadth of individuals to that of the laboratory population. By offering four different prey snail species, at a range of relative abundances, we show that there are consistent patterns in feeding. Importantly, the consumption of each prey was independent of the relative abundance at which they were present. Individual predators showed selectivity to a particular prey, i.e. the population of assassin snails seems to be formed of individuals that specialise on different prey. Our findings would contribute to the recent revision and the ongoing debate on the classification of predator species into generalists and specialists.


Assuntos
Cadeia Alimentar , Comportamento Predatório , Animais , Comportamento Alimentar , Modelos Biológicos , Caramujos
19.
Gene ; 824: 146389, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35257790

RESUMO

Mechanisms of reproductive isolation between closely related sympatric species are of high evolutionary significance as they may function as initial drivers of speciation and protect species integrity afterwards. Proteins involved in the establishment of reproductive barriers often evolve fast and may be key players in cessation of gene flow between the incipient species. The five Atlantic Littorina (Neritrema) species represent a notable example of recent radiation. The geographic ranges of these young species largely overlap and the mechanisms of reproductive isolation are poorly understood. In this study, we performed a detailed analysis of the reproductive protein LOSP, previously identified in Littorina. We showed that this protein is evolutionary young and taxonomically restricted to the genus Littorina. It has high sequence variation both within and between Littorina species, which is compatible with its presumable role in the reproductive isolation. The strongest differences in the LOSP structure were detected between Littorina subgenera with distinctive repetitive motifs present exclusively in the Neritrema species, but not in L. littorea. Moreover, the sequence of these repetitive structural elements demonstrates a high homology with genetic elements of bacteria, identified as components of Littorina associated microbiomes. We suggest that these elements were acquired from a symbiotic bacterial donor via horizontal genetic transfer (HGT), which is indirectly confirmed by the presence of multiple transposable elements in the LOSP flanking and intronic regions. Furthermore, we hypothesize that this HGT-driven evolutionary innovation promoted LOSP function in reproductive isolation, which might be one of the factors determining the intensive cladogenesis in the Littorina (Neritrema) lineage in contrast to the anagenesis in the L. littorea clade.


Assuntos
Microbiota , Caramujos , Animais , Bactérias , Fluxo Gênico , Especiação Genética , Isolamento Reprodutivo , Caramujos/genética
20.
Acta Trop ; 230: 106396, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35283103

RESUMO

Heterorhabditis bacteriophora is an entomopathogenic nematode (EPN) that is mutually associated with Photorhabdus luminescens, utilized globally for biological control of numerous organisms. Freshwater snails of the species Biomphalaria glabrata have been incriminated as the main intermediate hosts of Schistosoma mansoni in Brazil, but virtually nothing is known about the susceptibility of these gastropod to EPNs. Information in this respect is relevant for control of these intermediate hosts, and thus of the helminthiases they transmit. This paper for the first time reports the susceptibility of B. glabrata to infective juveniles of H. bacteriophora (isolate HP88) under laboratory conditions. For that purpose, six groups were formed: three Control groups (not exposed) and three Treated groups, in which the snails were exposed to 300 juveniles infecting the nematode over three weeks. The entire experiment was conducted in triplicate, using a total of 270 snails. Significant physiological alterations in B. glabrata were observed in response to the infection by H. bacteriophora HP88, characterized by decreased levels of hemolymphatic glucose as well as reduced contents of glycogen stored in the host's digestive gland. In parallel, the hemolymphatic activity of lactate dehydrogenase increased in the infected snails, indicating that the infection induces breakdown of carbohydrate homeostasis in B. glabrata. Additionally, all the reproductive parameters analyzed were reduced as a consequence of the infection. The results indicate the occurrence of the phenomenon of parasitic castration in the B. glabrata/H. bacteriophora HP88 interface, probably due to the depletion of galactogen in the parasitized organism. Although the infection did not cause lethality in the population of infected snails, H. bacteriophora HP88 compromised the reproductive performance of B. glabrata, suggesting its applicability in programs for biological control of this planorbid.


Assuntos
Biomphalaria , Rabditídios , Esquistossomose , Animais , Biomphalaria/parasitologia , Rabditídios/fisiologia , Schistosoma mansoni/fisiologia , Caramujos
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