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1.
Mar Pollut Bull ; 143: 33-41, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31789163

RESUMO

The effects of CO2-related acidification on two crustacean populations, the isopod Cyathura carinata and the amphipod Elasmopus rapax, were studied. Three pH levels were tested: artificial seawater without CO2 injection and two levels of reduced pH. Even though RNA:DNA ratio was reduced for both species, no statistical significant differences were found between the control and the treatments. Both species experienced a reduction in survivorship, longevity and the body length of surviving animals; although the impairment observed in E. rapax was more severe than in C. carinata. The long life span isopod and the short life span amphipod experienced a high degree of impairment in the reproduction, likely due to the reallocation of resources from reproduction to body maintenance and increasing survival by postponing the brood production. Regardless of the underlying processes and the energetic pathways, both experienced failure to reproduce, which could lead to the local extinction of these species.


Assuntos
Anfípodes/fisiologia , Dióxido de Carbono , Isópodes/fisiologia , Reprodução/fisiologia , Água do Mar/química , Anfípodes/anatomia & histologia , Anfípodes/genética , Animais , Tamanho Corporal , Ecotoxicologia , Sedimentos Geológicos/química , Concentração de Íons de Hidrogênio , Isópodes/anatomia & histologia , Isópodes/genética , Mortalidade , Especificidade da Espécie
2.
BMC Evol Biol ; 19(1): 207, 2019 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703555

RESUMO

BACKGROUND: Parasite attachment structures are critical traits that influence effective host exploitation and survival. Morphology of attachment structures can reinforce host specificity and niche specialisation, or even enable host switching. Therefore, it is important to understand the determinants of variation in attachment structures. Cymothoid isopods are striking ectoparasites of fishes that include the infamous 'tongue-biters.' They are known to parasitise hosts in one of four qualitatively distinct anatomical regions. Here, we quantify variation in cymothoid attachment structures - hook-like appendages called dactyli - and test whether differences in dactylus shape are correlated with parasite mode (where they attach), allometry, or both, using multivariate ordinary least squares regression. We also assess the influence of shared ancestry on shape using a molecular phylogeny to weight our models using phylogenetic generalised least squares regression. RESULTS: We find clear differences in shape between externally-attaching and internally-attaching cymothoids but also between anterior and posterior dactyli across various species with the same attachment mode. Allometric effects are significant for anterior but not posterior dactyli. Mouth-attaching species show greater shape variability than gill- and mouth-attaching species. We find no evidence that there are clade-specific patterns of association between parasite mode and dactylus shape. CONCLUSIONS: Parasite mode appears to be the main driver of attachment morphology. This likely reflects several components of parasite ecology including feeding and functional demands of attachment in different microhabitats. Geometric morphometric approaches to the quantification of shape variation of simple structures is an effective tool that provides new insights into the evolvability of parasite attachment.


Assuntos
Ectoparasitoses/veterinária , Doenças dos Peixes/parasitologia , Interações Hospedeiro-Parasita , Isópodes/anatomia & histologia , Isópodes/fisiologia , Animais , Ectoparasitoses/parasitologia , Feminino , Peixes , Brânquias/parasitologia , Isópodes/classificação , Masculino , Boca/parasitologia , Filogenia
3.
Zootaxa ; 4683(4): zootaxa.4683.4.5, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31715911

RESUMO

We describe a new species of Stenasellus Dollfus, 1897 (Isopoda: Asellota: Stenasellidae) from stagnant freshwater habitats in a cave on Socotra Island, Yemen. S. taitii n. sp. is the first endemic stenasellid found in Socotra, showing relatively closer morphological affinities to species from the Middle East (Oman, Iran) than from the African mainland, corresponding to the known paleogeographical connection of the archipelago to Southern Arabia. With notes on the protection of Socotran groundwaters.


Assuntos
Isópodes , Animais , Arábia , Irã (Geográfico) , Ilhas , Oriente Médio , Omã , Iêmen
4.
Zootaxa ; 4683(3): zootaxa.4683.3.7, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31715921

RESUMO

Xenuraega bythionekta sp. nov., is described from a single specimen taken off southern Japan. It is the second species of Xenuraega Tattersall, 1909, and extends the known range of the genus from North Atlantic to the northern Pacific Ocean. The species is characterized by the posteriorly narrowed pleotelson, and both uropodal rami being elongate and provided with a mass of long plumose setae. Xenuraega bythionekta sp. nov. is known only from the type locality, Kagoshima Prefecture, southern Japan at a depth of 1178-1179 m.


Assuntos
Isópodes , Distribuição Animal , Animais , Japão , Oceano Pacífico
5.
Zootaxa ; 4590(2): zootaxa.4590.2.5, 2019 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-31716094

RESUMO

Species of the bopyrid isopod genus Rhopalione Pérez, 1920, are parasites of Indo-West Pacific pinnotherid crabs. Unlike other bopyrid parasites of brachyurans that occupy the branchial chambers, however, species of Rhopalione (subfamily Pseudioninae) infest the abdominal cavity. Prior to the present study, four species of Rhopalione were recognized: R. atrinicolae Page, 1985 (New Zealand), R. incerta (Bonnier, 1900) (Madagascar), R. sinensis Markham, 1990 (East Asia), and R. uromyzon Pérez, 1920 (Persian Gulf). A fifth species of Rhopalione, from Perhentian Besar, Malaysia, is described herein, parasitic on the pinnotherid crab Serenotheres besutensis (Serène, 1967). Keys are provided to females and males of the species in the genus.


Assuntos
Braquiúros , Isópodes , Parasitos , Animais , Extremo Oriente , Feminino , Madagáscar , Malásia , Masculino , Nova Zelândia
6.
Zootaxa ; 4624(3): zootaxa.4624.3.6, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31716213

RESUMO

A new freshwater isopod, Caecidotea camaxtli sp. nov. (Isopoda, Asellidae) is described from Mexico. The new species can be distinguished from all other species of Caecidotea by the presence of cuticular scales on the caudal process, as well as a short and simple cannula in the apex of the endopodite of pleopod II. [Zoobank URL: urn:lsid:zoobank.org:act:082CF870-ABC3-4E25-B5F2-8CA59359C2B0].


Assuntos
Isópodes , Animais , Meio Ambiente , Água Doce , México
7.
Zootaxa ; 4622(1): zootaxa.4622.1.1, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31716284

RESUMO

The parasitic isopod family Cymothoidae Leach, 1818 of the India exclusive economic zone is reviewed. A total of 56 nominal species corresponding to 48 valid species belonging to sixteen genera are reviewed from 73 host species belonging to 35 families. Mothocya plagulophora (Haller, 1880), Nerocila depressa Milne Edwards, 1840, Nerocila loveni Bovallius, 1887, Nerocila trichiura (Miers, 1877), Norileca triangulata (Richardson, 1910) and Ryukyua globosa Williams Bunkley-Williams, 1994 are redescribed. Indusa pustulosa Pillai, 1954 is synonymised with Agarna malayi Tiwari, 1952; Cymothoa krishnai Jayadev Babu Sanjeeva Raj, 1984 is synonymised with Cymothoa eremita (Brünnich, 1783) and Nerocila priacanthusi Kumari, Rao Shyamasundari, 1987 is synonymised with Nerocila arres Bowman Tareen, 1983. Ourozeuktes bopyroides (Lesueur, 1814) is revised and excluded from the Indian fauna. The Indian cymothoid species Agarna bengalensis Kumari, Rao Shaymasundari, 1990, Cymothoa asymmetrica Pillai, 1954 and Nerocila hemirhamphusi Shyamasundari, Rao Kumari, 1990 are regarded here as species inquirenda. A key to the Indian genera of the family Cymothoidae and keys to the Indian species of the genera Cymothoa, Joryma, Mothocya, and Nerocila are presented. A checklist of the valid Cymothoidae species until now reported from Indian marine fishes are compiled. Host preferences, morphological variability and distribution are discussed.


Assuntos
Isópodes , Parasitos , Animais , Crustáceos , Peixes , Especificidade de Hospedeiro , Índia
8.
Zootaxa ; 4564(2): zootaxa.4564.2.6, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-31716505

RESUMO

To date, approximately 190 species of terrestrial isopods are known from Brazil and only 14 are considered troglobiotic. After the examination of a large collection from caves in Bambuí and Una geomorphological areas, along the states of Bahia, Minas Gerais and Goiás, two new troglobiotic species were recognized. Pectenoniscus liliae Campos-Filho, Bichuette Taiti sp. n. (Styloniscidae) is described from Serra do Ramalho karst area, and Benthana xiquinhoi Campos-Filho, Bichuette Taiti sp. n. (Philosciidae) from sandstone caves of Chapada Diamantina region. The latter constitutes the second troglomorphic species of the genus. Xangoniscus aganju (Styloniscidae) is also recorded from two caves in the Serra do Ramalho karst area. The systematic position of Iuiuniscus iuiuensis is briefly discussed and Venezillo congener (Armadillidae) is redescribed from São Domingos karst area.


Assuntos
Isópodes , Animais , Brasil , Malpighiales
9.
Zootaxa ; 4657(3): zootaxa.4657.3.4, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31716771

RESUMO

Alpioniscus (Illyrionethes) is a widespread subgenus of Trichoniscidae in the Dinaric Karst with 15 nominal troglobiotic species. Here we redescribe Alpioniscus (Illyrionethes) magnus and describe three new species (A. lossinii n. sp., A. drazinai n. sp., and A. mandalinae n. sp.) restricted to coastal areas. As a result, 18 nominal Illyrionethes species are known from the Dinaric Karst.


Assuntos
Isópodes , Animais
10.
Zootaxa ; 4609(1): zootaxa.4609.1.2, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31717118

RESUMO

Eleven species including six new species of Gnathiidae (Crustacea, Isopoda, Cymothoida) are reported from the Heron Island and Wistari Reef, Capricorn Group, southern Great Barrier Reef: Elaphognathia queenslandica sp. nov., Gnathia acrorudus sp. nov., Gnathia capricornica sp. nov., Gnathia carinodenta sp. nov., Gnathia formosa sp. nov. and Gnathia glaucostega sp. nov. Gnathia cornuta Holdich Harrison, 1980 and Gnathia grutterae Ferreira, Smit Davies, 2010 are for the first time reported from Heron Island and new records from Heron Island are provided for Gnathia biorbis Holdich Harrison, 1980, Gnathia variobranchia Holdich Harrison, 1980, and Gnathia wistari Svavarsson Bruce, 2012.


Assuntos
Isópodes , Animais , Aves , Ilhas
11.
PLoS Biol ; 17(10): e3000438, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31600190

RESUMO

Microbial endosymbiosis is widespread in animals, with major ecological and evolutionary implications. Successful symbiosis relies on efficient vertical transmission through host generations. However, when symbionts negatively affect host fitness, hosts are expected to evolve suppression of symbiont effects or transmission. Here, we show that sex chromosomes control vertical transmission of feminizing Wolbachia endosymbionts in the isopod Armadillidium nasatum. Theory predicts that the invasion of an XY/XX species by cytoplasmic sex ratio distorters is unlikely because it leads to fixation of the unusual (and often lethal or infertile) YY genotype. We demonstrate that A. nasatum X and Y sex chromosomes are genetically highly similar and that YY individuals are viable and fertile, thereby enabling Wolbachia spread in this XY-XX species. Nevertheless, we show that Wolbachia cannot drive fixation of YY individuals, because infected YY females do not transmit Wolbachia to their offspring, unlike XX and XY females. The genetic basis fits the model of a Y-linked recessive allele (associated with an X-linked dominant allele), in which the homozygous state suppresses Wolbachia transmission. Moreover, production of all-male progenies by infected YY females restores a balanced sex ratio at the host population level. This suggests that blocking of Wolbachia transmission by YY females may have evolved to suppress feminization, thereby offering a whole new perspective on the evolutionary interplay between microbial symbionts and host sex chromosomes.


Assuntos
Isópodes/genética , Cromossomos Sexuais , Processos de Determinação Sexual , Simbiose/genética , Wolbachia/fisiologia , Alelos , Animais , Feminino , Genótipo , Homozigoto , Isópodes/microbiologia , Masculino , Modelos Genéticos , Característica Quantitativa Herdável , Razão de Masculinidade
12.
Physiol Biochem Zool ; 92(6): 531-543, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31556843

RESUMO

Cellulose is an abundant source of carbon, accounting for more than 50% of foliage and 90% of woody tissues of plants. Despite the diversity of species that include living or dead plant tissue in their diets, the ability to digest cellulose through self-produced enzymatic machinery is considered rare in the animal kingdom. The majority of animals studied to date rely on the cellulolytic activity of symbiotic microorganisms in their digestive tract, with some evidence for a complementary action of endogenous cellulases. Terrestrial isopods have evolved a lifestyle including feeding on a lignocellulose diet. Whether isopods utilize both external and internal cellulases for digestion of a diet is still not understood. We experimentally manipulated the content of cellulose (30%, 60%, or 90%) and the amount of biofilm (small or large) in the offered food source and quantified growth and cellulolytic activity in the gut of the isopod Porcellio scaber. The presence of a visible biofilm significantly promoted isopod growth, regardless of the cellulose content in the diet. The activity of gut cellulases was not significantly affected by the amount of biofilm or the cellulose content. Our results do not support a significant contribution of either ingested or host enzymes to cellulose utilization in P. scaber. Cellulose might not represent a key nutrient for isopods and does not seem to affect the nutritional value of the diet-associated biofilm. We propose that it is the biofilm community that determines the quality of plant diet in terrestrial isopods and potentially also in other detrital plant feeders.


Assuntos
Ração Animal , Biofilmes , Celulose , Isópodes/crescimento & desenvolvimento , Animais , Dieta
13.
Microsc Res Tech ; 82(12): 2014-2025, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31471999

RESUMO

To estimate trace element bioaccumulation in Armadillo officinalis, specimens were collected from Ghar El Melh lagoon then exposed for 3 weeks in contaminated sediments with copper, zinc, and cadmium. From the first week until the end of the experiment, a decrease in A. officinalis growth related to the increase of Cd concentration in the sediment was recorded. However, a mass gain was highlighted under Cu and Zn exposures. At the end of experiment, body metal concentrations were measured using flame atomic emission spectrometry. Results of the bioaccumulation factor showed that the species could be considered as a macroconcentrator of copper (BAF > 2) and a deconcentrator of zinc (BAF < 2). Microscopy observations of hepatopancreas cells showed morphological and histological changes even at the lowest concentration. They consisted in the microvillus border destruction, lipid droplets modifications, trace element accumulation, and the condensation of the majority of cellular organelles. The degree of these alterations was found to be dose-dependent. Through these results, the isopod A. officinalis could be used as relevant monitor organisms for soil metal contamination.


Assuntos
Bioacumulação , Cádmio/farmacocinética , Cobre/farmacocinética , Isópodes/química , Oligoelementos/análise , Zinco/farmacocinética , Animais , Cádmio/toxicidade , Cobre/toxicidade , Poluição Ambiental/análise , Sedimentos Geológicos/química , Hepatopâncreas/química , Hepatopâncreas/citologia , Isópodes/ultraestrutura , Tunísia , Zinco/toxicidade
14.
Med Arch ; 73(2): 131-133, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31391704

RESUMO

Introduction: Diabetic foot ulcer (DFU) is a common lower-extremity complication in patients with diabetes mellitus. A novel DFU treatment is tested by using an ointment containing as healing agent olive oil isopod Ceratothoa oestroidesextract. Case report: A 58 years old obese man,smoker, with a history of unregulated Type 2 Diabetes Mellitus, peripheral neuropathy and Hodgkin lymphoma was referred to Athens-Greece university hospital Laikon. The patient presented clinically with a lower extremity DFU and peripheral neuropathy with dysesthesia and disturbed sensation of hot and cold. He was treated with an ointment containing C. oestroides extract for five months, without any antimicrobial treatment. Therapy was evaluated by measurement of the transepidermal water loss, skin hydration, photo documentation and planimetry. At each patient's visit, DFU presented a satisfactory healing process. Five months after treatment initiation the patient had complete healing of his DFU. Blood tests after treatment revealed a significant reduction of the levels of the inflammatory markers. Ulcer cultures did not reveal any microbial development neither before nor after treatment. Conclusion: The administration of the C. oestroides extract ointment proved to be effective in this case. Although these results should be further investigated, the reported case suggests a novel option for the management of neuropathic diabetic foot ulcers, especially in patients with severe co-morbidities.


Assuntos
Pé Diabético/terapia , Isópodes , Pomadas/uso terapêutico , Extratos de Tecidos/uso terapêutico , Animais , Diabetes Mellitus Tipo 2/complicações , Pé Diabético/complicações , Pé Diabético/imunologia , Neuropatias Diabéticas/complicações , Doença de Hodgkin/complicações , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Fumar , Resultado do Tratamento , Cicatrização
15.
Chemosphere ; 237: 124480, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31394449

RESUMO

The use of degradable chelating agent to enhance phytoextraction is a promising and low-cost method for remediation of heavy metals-polluted soil. However, very limited information is available regarding the effect of chelating agent combinations on plant growth and its capacity to extract metals. In this study, a pot experiment was conducted to evaluate the applicability of [N, N]-bis glutamic acid (GLDA), nitrilotriacetic acid (NTA), [S, S]- ethylenediamine disuccinic acid (EDDS), and citric acid (CA) alone and in combination to enhance the phytoextraction efficiency of amaranth (Amaranthus hypochondriacus L.) in two Cd-contaminated agricultural soils (S1 soil 2.12 mg/kg and S2 soil 2.89 mg/kg; the environmental standard value of Cd in agricultural soils in China is lower than 0.8 mg/kg). The results showed that, except for EDDS, other treatments had no obvious effect on plant biomass, and even promoted biomass increase to reach 1.06 (S1), 2.07 (S2) g/pot. The increase in total Cd extraction amount by 5 mM of single chelators GLDA and NTA reached 3.87 and 2.81 (S1), and 3.28 and 2.50 (S2) times that of the control group, respectively. For complexed chelating agents, G-N (GLDA + NTA) combinations (GLDA = 3 mM, NTA = 2 mM) extracted the highest amount of Cd compared with other treatments, reaching 0.36 and 0.52 mg/pot (4.50 and 3.71 times that of the control group), respectively. The order of extraction amount was G-N > GLDA > NTA > G-E (GLDA + EDDS) > G-C (GLDA + CA) > CA (5 mM total Cd concentration). Moreover, soil enzyme activity of G-N treatment increased significantly compared to that of the control group, indicating the great application potential of a composite chelating agent relative to a single chelating agent. Therefore, degradable chelators, especially the G-N combination, can effectively increase the available Cd content and greatly enhance the ability of plants to absorb and transport Cd in soils.


Assuntos
Amaranthus/metabolismo , Biodegradação Ambiental , Cádmio/metabolismo , Quelantes/química , Poluentes do Solo/metabolismo , Animais , Biomassa , Cádmio/análise , China , Ácido Cítrico , Etilenodiaminas , Isópodes , Metais Pesados/análise , Ácido Nitrilotriacético , Solo , Poluentes do Solo/análise
16.
Parasit Vectors ; 12(1): 387, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31370874

RESUMO

BACKGROUND: Anilocra capensis Leach, 1818 is the only named species of Anilocra Leach, 1818 from South Africa. Anilocra is a large genus (> 40 species) with high levels of diversity reported from the Caribbean and Indo-West Pacific. Considering it is highly unlikely that all records of Anilocra from South Africa can be of a single species, the aim of this study was to better understand the diversity of Anilocra from this region and continent. METHODS: To redescribe A. capensis, the syntypes of A. capensis and specimens recorded as A. capensis from Africa were borrowed from the Natural History Museum, London, UK, and The iZiko South African Museum, Cape Town. Newly collected fresh samples of A. capensis were collected from off Cape Town, South Africa. Morphological redescriptions of the syntypes, and other museum and fresh material were conducted. Fresh samples were used to characterise molecularly A. capensis using the mitochondrial cytochrome c oxidase subunit 1 gene (cox1). RESULTS: Morphological analyses demonstrated that apart from A. capensis there are six Anilocra species new to science from Africa: Anilocra ianhudsoni n. sp., Anilocra bunkleywilliamsae n. sp., Anilocra paulsikkeli n. sp., Anilocra jovanasi n. sp., Anilocra angeladaviesae n. sp. and Anilocra hadfieldae n. sp. Of the species under study, specimens of A. capensis appear to demonstrate the most individual variation, which occurs in pleonite width, pleotelson form and uropod length. We determined that African species of Anilocra can be primarily differentiated by the proportional shape and size of the full body in dorsal view and pereonites 1, 6 and 7. Other defining morphological traits include proportional shape and size of the pereopods, and the antenna and antennula peduncles. Lastly, the molecular characterisation of A. capensis is provided and the interspecific divergence with Mediterranean species is smaller than that with Caribbean species. CONCLUSIONS: The results of this study provide a detailed redescription of A. capensis and the first molecular barcode for this organism. Six new species of Anilocra from Africa are described, establishing that the diversity of Anilocra in this region is greater than previously known. With this new understanding of species differences, we can accurately conduct detailed molecular and ecological analyses of Anilocra from Africa with certainty of the organism under study.


Assuntos
Ectoparasitoses/veterinária , Peixes/parasitologia , Variação Genética , Isópodes/classificação , Animais , Ectoparasitoses/parasitologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Isópodes/fisiologia , Masculino , Filogenia , Análise de Sequência de DNA , África do Sul
17.
Artigo em Inglês | MEDLINE | ID: mdl-31400475

RESUMO

Ingestion of microplastics can impair nutrition of marine invertebrates. In a laboratory study, we tested whether microplastics affect ingestion rates and gastrointestinal enzyme activities in the marine isopod Idotea emarginata. Isopods were fed for eight days with one out of four different food formulations: natural food (the brown alga Fucus vesiculosus) or synthetic diet consisting of freeze-dried algal powder embedded in agarose, both, with or without microplastic particles (fluorescent polymethyl methacrylate, 10-100 µm) at a concentration of 40 items per mg of food. The isopods accepted both types of food but consumed significantly more (average 3.1-fold) of the agar based synthetic food. I. emarginata responded to the reduced content of digestible organic matter in the synthetic food by a compensatory adjustment of the ingestion rates. Addition of microplastics had no effect on ingestion rates in natural food whereas the feeding rates for synthetic food varied in response to microplastics. Similarly, activity patterns of digestive enzymes, particularly those of esterases, changed significantly in the treatment with synthetic food. Isopods fed with synthetic food alone showed elevated esterase activities in the gut while those isopods fed with synthetic food and microplastics showed elevated esterase activities in the midgut gland but not in the gut. Apparently, not the exposure to microplastic alone, but the combined effects of reduced nutrient availability and microplastic ingestion caused considerable biochemical reactions in the digestive organs of the isopods.


Assuntos
Ração Animal , Sistema Digestório/enzimologia , Esterases/metabolismo , Isópodes/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/fisiologia , Ingestão de Alimentos , Monitoramento Ambiental
18.
Parasit Vectors ; 12(1): 415, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31443734

RESUMO

BACKGROUND: Although parasitic isopods can negatively affect the reproduction and ingestion of several commercially important crustaceans, little is known regarding the mechanisms that underlie these effects. METHODS: In the present study, the iTRAQ (isobaric tags for relative and absolute quantification) approach was applied to identify differentially expressed proteins in the Chinese grass shrimp Palaemonetes sinensis infected with the parasitic isopod Tachaea chinensis. RESULTS: On the basis of our analysis, we identified 1262 proteins from a total of 4292 peptides. There was a significant difference in the expression of 182 proteins between the control and infected groups, among which 69 were upregulated and 113 were downregulated after T. chinensis infection. The differentially expressed proteins revealed that parasitism may inhibit the immune response, thereby increasing host vulnerability to additional lethal infection. Furthermore, T. chinensis may secrete anticoagulants to inhibit hemolymph clotting. Moreover, the isopod parasite placed a heavy metabolic burden on the host, particularly with respect to glucose metabolism. CONCLUSIONS: Our study is the first to use the iTRAQ-based proteomic approach to analyze the effects of an isopod parasite on its host. The results we obtained using this approach will make a valuable contribution to understanding the molecular mechanisms underlying isopod parasitism on crustaceans.


Assuntos
Interações Hospedeiro-Parasita/genética , Isópodes/patogenicidade , Palaemonidae/parasitologia , Proteoma , Proteínas de Frutos do Mar/análise , Animais , Palaemonidae/genética
19.
Oecologia ; 190(4): 783-797, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31267237

RESUMO

Predation on parasites is an important ecological process, but few experimental studies have examined the long-term impacts on the prey. Cleaner fish prey upon large numbers and selectively feed on the larger individuals of the ectoparasitic stage of gnathiid isopods. Removal of cleaner fish Labroides dimidiatus for 1.5-12.5 years negatively affects coral reef fishes, but the mechanism is unclear. A reduction in local parasite populations or the size of individual parasites would benefit all susceptible fishes. We tested whether cleaner presence reduces local gnathiid populations using 18 patch-reefs distributed between two sites (both at Lizard Island, Great Barrier Reef) which were maintained cleaner-free or undisturbed for 12 years. Using emergence traps (1 m2), free-living gnathiid stages were sampled before and after cleaner fish were removed during the day and night, up to 11 times over the course of the experiment. There were effects of the removal in the predicted direction, driven largely by the response at one site over the other involving 200% more gnathiids, but manifested only in the daytime sampling after 4 months. There was also a main effect (36%) for the shared sample dates at both sites after 12 years. Gnathiid size occasionally differed with cleaner presence, but in no consistent way over time. Contrary to our predictions, changes in free-living gnathiid population numbers and their size structure rarely reflected the changes in fish populations and individuals observed on cleaner-free reefs. Therefore, evidence that this predator alone regulates gnathiids remains limited, suggesting other contributing processes are involved.


Assuntos
Isópodes , Parasitos , Perciformes , Animais , Recifes de Corais , Peixes
20.
Chemosphere ; 235: 498-509, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31276864

RESUMO

Anthropogenic substances pollute freshwater systems worldwide, with serious, long-lasting effects to aquatic biota. Present methods of detecting elevated levels of trace metal pollutants are typically accurate but expensive, and therefore not suitable for applications requiring high spatial resolution. Additionally, these methods are not efficient solutions for the determination of long-term averages of pollution concentration. This is the rationale for the implementation of a biomonitoring programme as an alternative means of pollutant detection. This review summarises recent literature concerning the past and potential uses of the benthic isopod Asellus aquaticus as a biomonitor for pollution in freshwater systems. Recent studies indicate that A. aquaticus is well suited for this purpose. However, the mechanisms by which it bioaccumulates toxins have yet to be fully understood. In particular, the interactions between coexisting trace metal pollutants in the aquatic environment have only recently been considered, and it remains unclear how a biomonitoring programme should adapt to the effects of these interactions. It is evident that failing to account for these additional stressors will result in an ineffective biomonitoring programme; for this reason, a comprehensive understanding of the bioaccumulation mechanisms is required in order to reliably anticipate the effects of any interferences on the outcome.


Assuntos
Monitoramento Ambiental/métodos , Isópodes/fisiologia , Poluentes da Água/metabolismo , Animais , Água Doce , Isópodes/efeitos dos fármacos , Oligoelementos/farmacologia , Poluentes da Água/análise
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