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1.
Dokl Biochem Biophys ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38955915

RESUMO

Metacestode infestation of Semibalanus balanoides (L., 1767) and Balanus crenatus Bruguiеre, 1789, collected in the Barents and White Seas and in the northern part of the Sea of Okhotsk in 2020 and 2021, respectively, was studied. A total of 313 S. balanoides from Mogilnaya Bay of Kildin Island (Barents Sea) and isolated mature wrinkled barnacles B. crenatus, two and four specimens from the Pechora Sea and Kandalaksha Bay of the White Sea, respectively, were examined in 2020. Metacestodes Fimbriarioides intermedia (Fuhrmann, 1913) (Cyclophyllidea, Hymenolepididae) were found in 1.0 ± 0.6% of S. balanoides in the Barents Sea with an invasion intensity (I. I.) of 2-5 specimens, and in one of two B. crenatus from the Pechora Sea (I. I. 15 specimens). For the first time, in both B. crenatus from the Pechora Sea, taken from the valves of the mussel Mytilus edulis, metacestodes Microsomacanthus sp. I (I. I. 13 and 20 specimens) with proboscis hooks 38-41 (39.4 ± 0.1) µm long and blades of 9.5-11 (10.7 ± 0.1) µm were obtained. One of four B. crenatus from the Kandalaksha Bay was infected with another Microsomacanthus sp. II (I. I. 19 specimens) with proboscis hooks 44.0-49.5 (45.7 ± 0.5) µm long and blades 14.0-16.0 (14.8 ± 0.07) µm long. A total of 362 S. balanoides were collected and dissected in Gizhiginskaya Bay of the northern part of the Sea of Okhotsk in 2021, of which 8.0 ± 1.4% were infected with F. intermedia metacestodes (I. I. 1-19 specimens). Study results of the infestation of S. balanoides on the Koni-Pyagin coast of the Sea of Okhotsk (according to the collections of 2006-2007) were supplemented and clarified. Description of metacestodes and the taxonomic affiliation of cysticercoids Microsomacanthus spp. are given.

2.
Heliyon ; 10(11): e31683, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38828329

RESUMO

The application of enzymes as antifoulants is one of the environment-friendly strategies in biofouling management. In this study, antifouling activities of commercially available proteinase K and α-amylase enzymes were evaluated using barnacle larva and biofilm-forming bacteria as test organisms. The enzymes were also tested against barnacle cement protein through in silico analysis. The results showed that both enzymes inhibited the attachment of bacteria and settlement of barnacle larvae on the test surface. The lowest minimum inhibitory concentration of 0.312 mg ml-1 was exhibited by proteinase K against biofilm-forming bacteria. The calculated LC50 values for proteinase K and α-amylase against the barnacle nauplii were 91.8 and 230.96 mg ml-1 respectively. While α-amylase showed higher antibiofilm activity, proteinase K exhibited higher anti-larval settlement activity. Similarly, in silico analysis of the enzymes revealed promising anti-settlement activity, as the enzymes showed good binding scores with barnacle cement protein. Overall, the results suggested that the enzymes proteinase K and α-amylase could be used in antifouling coatings to reduce the settlement of biofouling on artificial materials in the marine environment.

3.
Curr Biol ; 34(1): 196-203.e2, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38194916

RESUMO

Innovation is a key to evolutionary success and entrance into novel ecosystems.1 Species that float freely at the ocean's surface, termed obligate neuston (also called pleuston, here referred to simply as neuston), include highly specialized taxa from distinct evolutionary lineages that evolved floating morphologies.2 In 1958, Soviet scientist, A.I. Savilov,3 stated that floating animal species are derived from benthic ancestors, rather than species from the adjacent pelagic zone, and that floating morphologies are homologous to benthic attachment structures. To test Savilov's hypothesis, we constructed molecular phylogenies and ancestral states for all major floating groups for which molecular data were available. Our results reveal that four of the five clades examined arose directly from a substrate-attached ancestor, although that substrate was not necessarily the benthos, as Savilov stated, and instead included epibiotic and rafting ancestors. Despite their diverse evolutionary origins, floating animals use gas-trapping mechanisms to remain at the surface,4,5,6 and many of these gas-trapping structures appear to be homologous to substrate attachment structures. We also reconstruct the trophic habits of floating mollusks and their sister species, revealing that prey preference remains conserved upon entering the ocean's surface ecosystem. Colonization of the ocean's surface seems to have occurred through successive evolutionary steps from the seafloor. Our results suggest that these steps often included transitions through epibiotic (where species attach to other living organisms) or rafting (where species attach to floating debris) habits. The water-air interface, despite its unique properties, may, in some ways, be just another substrate.


Assuntos
Ecossistema , Hábitos , Animais , Água , Oceanos e Mares
4.
Integr Zool ; 19(2): 200-223, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37248329

RESUMO

A diverse sessile barnacle fauna from a Miocene shallow-water deposit at Dolnja Stara vas in Slovenia is described. It includes the first descriptions of early post settlement juveniles of Actinobalanus sloveniensis attached to mangrove leaves. These represent three distinct growth phases, the earliest being interpreted as being less than 24 h post settlement, the others being 1 to 2 days post settlement. An assessment of their taphonomy is provided. Associated adult balanomorphs are attached to a variety of organic substrates, including mangrove leaves and branches, fragments of the conifers ?Taxodioxylon, Carapoxylon, pine cones, molluscs, and cetacean bones. The barnacles include A. sloveniensis, Amphibalanus venustus, and Perforatus perforatus-many with opercula retained within the shells. A. venustus retains some of the original shell color. This is the second record of barnacle-plant associations from the Central Paratethys from Kamnik and Trbovlje. The paleoecology and paleogeography of the site are discussed.


Assuntos
Fósseis , Thoracica , Animais , Cetáceos , Folhas de Planta , Água
5.
Mar Drugs ; 21(9)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37755093

RESUMO

Barnacles, a prevalent fouler organism in intertidal zones, has long been a source of annoyance due to significant economic losses and ecological impacts. Numerous antifouling approaches have been explored, including extensive research on antifouling chemicals. However, the excessive utilization of small-molecule chemicals appears to give rise to novel environmental concerns. Therefore, it is imperative to develop new strategies. Barnacles exhibit appropriate responses to environmental challenges with complex physiological processes and unique sensory systems. Given the assumed crucial role of bioactive peptides, an increasing number of peptides with diverse activities are being discovered in barnacles. Fouling-related processes have been identified as potential targets for antifouling strategies. In this paper, we present a comprehensive review of peptides derived from barnacles, aiming to underscore their significant potential in the quest for innovative solutions in biofouling prevention and drug discovery.


Assuntos
Incrustação Biológica , Thoracica , Animais , Incrustação Biológica/prevenção & controle , Descoberta de Drogas , Peptídeos/farmacologia
6.
Int J Biol Macromol ; 253(Pt 5): 127125, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37776922

RESUMO

Biomaterials with excellent biocompatibility, mechanical performance, and self-recovery properties are urgently needed for tissue regeneration. Inspired by barnacle cement and spider silk, we genetically designed and overexpressed a fused protein (cp19k-MaSp1) composed of Megabalanus rosa (cp19k) and Nephila clavata dragline silk protein (MaSp1) in Pichia pastoris. The recombinant cp19k-MaSp1 exhibited enhanced adhesion capability beyond those of the individual proteins in both aqueous and non-aqueous conditions. cp19k-MaSp1 protein fiber scaffolds prepared through electrospinning have adequate hydrophilicity compared to cp19k and MaSp1 protein fiber scaffolds, and offer improved overall porosity compared to MaSp1 protein fiber scaffolds. The cp19k-MaSp1 protein fiber scaffolds showed excellent proteolytically stable properties because of only 9.6 % depletion after incubation in a biodegradation solution for 56 d. The cp19k-MaSp1 protein fiber scaffolds present remarkably high extreme tensile strength (112.7 ± 11.6 MPa) and superior ductility (438.4 ± 43.9 %) compared with cp19k (34.4 ± 8.1 MPa, 115.4 ± 32.7 %) and MaSp1 protein fiber scaffolds (65.8 ± 9.3 MPa, 409.6 ± 23.1 %), also 68.4 % of tensile strength was recovered by incubation in K+ buffer after multiple stretches, which create a favorable cell adhesion, growth, and proliferation environment for human umbilical vein endothelial cells (HUVECs). The improved biocompatibility, extensive adhesion, mechanical strength, and self-recovery properties make the bioinspired synthetic cp19k-MaSp1 a potential candidate for biomedical tissue reconstruction.


Assuntos
Fibroínas , Aranhas , Thoracica , Animais , Humanos , Células Endoteliais , Seda
7.
Biodivers Data J ; 11: e105726, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37455699

RESUMO

Background: The characteristics of the Strait of Magellan promote the formation of unique environments, with diverse habitats and marine organisms. This fragmentation of the landscape generates diverse little-explored ecological associations, especially in the zone of sub-Antarctic islands of the Tierra del Fuego archipelago. One way to address this lack of knowledge is through the biotope characterization methodology, with ecological units composed of the habitat and the communities associated with these environments, obtaining data and information on the dominant and incidental taxonomic groups. This is a good research model to conduct baseline studies in coastal benthic marine environments. New information: A data set in Darwin Core standard is presented of the species that make up the intertidal biotopes of Clarence Island (Tierra del Fuego Archipelago, south of the Strait of Magellan). This includes 50 identified species and the specific coordinates for each sampled location, with a total of 1400 georeferenced records. Mollusks were the most diverse taxon with 21 species, followed by algae (14 species). Sessile organisms such as the barnacles Elminiuskingii and Austromegabalanuspsittacus predominate in these ecosystems, followed by bivalve mollusks such as Choromytiluschorus and Mytiluschilensis, which together with Nacellamagellanica and the alga Hildenbrandia sp. make up more than 50% of the total records. The inclusion of biotope patterns in this study complements the information on benthic marine flora and fauna in the intertidal zone, including new records for the coast in the Clarence Island area, which is within the boundary of the Kawésqar National Park.

8.
J Invertebr Pathol ; 198: 107913, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36940868

RESUMO

Cancer-like neoplasms are extremely rarely present in arthropods, particularly in crustaceans. Thus, it is assumed that these animals have some efficient cancer-preventing mechanisms. However, several cases of cancer-like neoplasms are described in crustaceans, though only for the Decapoda. We identified a tumor in the parasitic barnacle Peltogaster paguri (Cirripedia: Rhizocephala), and described its histological structure. A spherical cell mass consisting mostly of roundish cells with big translucent nuclei, prominent nucleoli, and sparse chromatin, and of cells with condensed chromosomes, was found in the main trunk of the P. paguri rootlet system. Numerous mitoses were observed in this area. Such tissue organization is utterly uncharacteristic of the Rhizocephala. Based on acquired histological data, we assume that this tumor is a cancer-like neoplasm. This is the first report of a tumor identified in the rhizocephalans, as well as in non-decapod crustaceans as a whole.


Assuntos
Artrópodes , Neoplasias , Parasitos , Thoracica , Animais , Interações Hospedeiro-Parasita , Neoplasias/veterinária
9.
Arthropod Struct Dev ; 72: 101227, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36436363

RESUMO

The complete larval development of Parasacculina pilosella (Van Kampen et Boschma, 1925) and Sacculina pugettiae Shiino, 1943 including five naupliar stages and one cypris stage is described and illustrated using SEM. P. pilosella and S. pugettiae have a sacculinid type of development. Nauplii possess a naupliar eye, short frontolateral horns with terminal processes, and a ventral process between the furcal rami. Larvae lack a flotation collar, seta 6 on the antennule and a seta on the antennal basis. Cyprids have a nearly straight LO2. Breakage zone and a spinous process are present only in male larvae. Nauplii of the two species differ by the morphology of the furca: in P. pilosella, the furcal rami are longer and not drowned into cuticular sockets. Naupliar antenna of S. pugettiae has a lateral seta on the endopod which is lacking in P. pilosella. Dorsal head shield setae 1 and 2a are present in S. pugettiae nauplii and not found in P. pilosella larvae. In P. pilosella, all dorsal setae have subterminal pores, whereas in S. pugettiae, pores of the setae 2 are shifted proximally. It is possible that the presence/absence of setae 1 and 2a is the distinctive feature of nauplii of the families Sacculinidae and Polyascidae.


Assuntos
Thoracica , Masculino , Animais , Thoracica/anatomia & histologia , Larva/anatomia & histologia , Microscopia Eletrônica de Varredura
10.
Comput Methods Biomech Biomed Engin ; 26(3): 350-372, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36218238

RESUMO

Multi-disease prediction is regarded as the capacity to simultaneously identify various diseases that are expected to be affected an individual at a certain period. These multiple diseases are seemed to be at various progression levels and need to be detected in the patient at the time of clinical visits. Diverse studies in the literature have included the predictive models for particular diseases yet, it is unable to notice humans with multiple diseases since humans are mostly suffered not only from a single disease but also from multiple diseases. Hence, this article aims to implement a novel multi-disease prediction model using an ensemble learning approach with deep features. The required data for the multi-disease prediction is collected from the standard datasets. Then, the collected data are given into the "Deep Belief Network (DBN)" approach, where the features are obtained from the RBM layers. These RBM features are tuned with the help of Deviation-based Hybrid Grasshopper Barnacles Mating Optimization (D-HGBMO) for improving the prediction performance. The optimized RBM features are considered in the ensemble learning model named Ensemble, in which the multi-disease prediction is performed with "Deep Neural Network (DNN), Extreme Learning Machine (ELM), and Long Short Term Memory." The predicted score from three classifiers is used in the optimized weighted score and thresholding-based final prediction using the same D-HGBMO for determining the accurate multi-disease prediction results. The experimental results show the effective performance of the proposed model by comparing it with the existing classifiers with the help of different quantitative measures.


Assuntos
Algoritmos , Redes Neurais de Computação , Humanos , Aprendizado de Máquina , Fatores de Tempo
11.
Biofouling ; 38(9): 876-888, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36503292

RESUMO

The biological impact of chemical formulations used in various coating applications is essential in guiding the development of new materials that directly contact living organisms. To illustrate this point, an investigation addressing the impact of chemical compositions of polydimethylsiloxane networks on a common platform for foul-release biofouling management coatings was conducted. The acute toxicity of network components to barnacle larvae, the impacts of aqueous extracts of crosslinker, silicones and organometallic catalyst on trypsin enzymatic activity, and the impact of assembled networks on barnacle adhesion was evaluated. The outcomes of the study indicate that all components used in the formulation of the silicone network alter trypsin enzymatic activity and have a range of acute toxicity to barnacle larvae. Also, the adhesion strength of barnacles attached to PDMS networks correlates to the network formulation protocol. This information can be used to assess action mechanisms and risk-benefit analysis of PDMS networks.


Assuntos
Incrustação Biológica , Thoracica , Animais , Tripsina , Biofilmes , Incrustação Biológica/prevenção & controle , Silicones/química
12.
Molecules ; 27(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36558114

RESUMO

This study has reviewed the naturally occurring bioadhesives produced in marine and freshwater aqueous environments and in the mucinous exudates of some terrestrial animals which have remarkable properties providing adhesion under difficult environmental conditions. These bioadhesives have inspired the development of medical bioadhesives with impressive properties that provide an effective alternative to suturing surgical wounds improving closure and healing of wounds in technically demanding tissues such as the heart, lung and soft tissues like the brain and intestinal mucosa. The Gecko has developed a dry-adhesive system of exceptional performance and has inspired the development of new generation re-usable tapes applicable to many medical procedures. The silk of spider webs has been equally inspiring to structural engineers and materials scientists and has revealed innovative properties which have led to new generation technologies in photonics, phononics and micro-electronics in the development of wearable biosensors. Man made products designed to emulate the performance of these natural bioadhesive molecules are improving wound closure and healing of problematic lesions such as diabetic foot ulcers which are notoriously painful and have also found application in many other areas in biomedicine. Armed with information on the mechanistic properties of these impressive biomolecules major advances are expected in biomedicine, micro-electronics, photonics, materials science, artificial intelligence and robotics technology.


Assuntos
Bivalves , Adesivos Teciduais , Animais , Inteligência Artificial , Adesivos/farmacologia , Seda , Adesivos Teciduais/química
13.
PeerJ ; 10: e14073, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36193430

RESUMO

Background: Large numbers of exotic marine species have been introduced worldwide. Monitoring of introduced species is important to reveal mechanisms underlying their establishment and expansion. Balanus glandula is a common intertidal barnacle native to the northeastern Pacific. However, this species has been introduced to Japan, South America, South Africa, and Europe. While a latitudinal genetic cline is well known in its native range, it is unclear whether such a genetic cline occurs in introduced areas. Twenty years have passed since it was first identified in Japan and its distribution now ranges from temperate to subarctic regions. Methods: In the present study, we examined genotypes of cytochrome oxidase subunit I (COI) of mitochondrial (mt)-DNA and elongation factor 1a (EF1) across the distribution of B. glandula in Japan at high and mid intertidal zones. Results: At all sampling sites, native northern genotypes are abundant and I did not detect significant effects of latitude, tide levels, or their interaction on genotypic frequencies. Further, I did not detect any change of genotype composition between data collected during a study in 2004 and samples in the present study collected in 2019. Data from the present study offer an important baseline for future monitoring of this species and supply valuable insights into the mechanisms of establishment and expansion of introduced marine species generally.


Assuntos
Thoracica , Animais , Thoracica/genética , Japão , Espécies Introduzidas , DNA Mitocondrial/genética , Europa (Continente)
14.
Proc Biol Sci ; 289(1982): 20221535, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36100022

RESUMO

The calcareous shell and sessile lifestyle are the representative phenotypes of many molluscs, which happen to be present in barnacles, a group of unique crustaceans. The origin of these phenotypes is unclear, but it may be embodied in the convergent genetics of such distant groups (interphylum). Herein, we perform comprehensive comparative genomics analysis in barnacles and molluscs, and reveal a genome-wide strong convergent molecular evolution between them, including coexpansion of biomineralization and organic matrix genes for shell formation, and origination of lineage-specific orphan genes for settlement. Notably, the expanded biomineralization gene encoding alkaline phosphatase evolves a novel, highly conserved motif that may trigger the origin of barnacle shell formation. Unlike molluscs, barnacles adopt novel organic matrices and cement proteins for shell formation and settlement, respectively, and their calcareous shells have potentially originated from the cuticle system of crustaceans. Therefore, our study corroborates the idea that selection pressures driving convergent evolution may strongly act in organisms inhabiting similar environments regardless of phylogenetic distance. The convergence signatures shed light on the origin of the shell and sessile lifestyle of barnacles and molluscs. In addition, notable non-convergence signatures are also present and may contribute to morphological and functional specificities.


Assuntos
Thoracica , Animais , Evolução Molecular , Genoma , Moluscos/genética , Filogenia , Thoracica/genética
15.
Sensors (Basel) ; 22(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36146336

RESUMO

The goal of this research is to accurately extract the parameters of the photovoltaic cells and panels and to reduce the extracting time. To this purpose, the barnacles mating optimizer algorithm is proposed for the first time to extract the parameters. To prove that the algorithm succeeds in terms of accuracy and quickness, it is applied to the following photovoltaic cells: monocrystalline silicon, amorphous silicon, RTC France, and the PWP201, Sharp ND-R250A5, and Kyocera KC200GT photovoltaic panels. The mathematical models used are single and double diodes. Datasets for these photovoltaic cells and panels were used, and the results obtained for the parameters were compared with the ones obtained using other published methods and algorithms. Six statistical tests were used to analyze the performance of the barnacles mating optimizer algorithm: the root mean square error mean, absolute percentage error, mean square error, mean absolute error, mean bias error, and mean relative error. The results of the statistical tests show that the barnacles mating optimizer algorithm outperforms several algorithms. The tests about the computational time were made using two computer configurations. Using the barnacles mating optimizer algorithm, the computational time decreases more than 30 times in comparison with one of the best algorithms, hybrid successive discretization algorithm.


Assuntos
Thoracica , Algoritmos , Animais , França , Modelos Teóricos , Silício
16.
Mar Environ Res ; 181: 105738, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36075156

RESUMO

Coral-associated invertebrates contribute much to the biodiversity of Caribbean coral reefs. Although the nature of their symbiotic relation is usually not fully understood, they can cause damage to their hosts, especially when they occur in high densities. The abundance of seven groups of coral-associated invertebrates was investigated on reefs along the leeward side of Curaçao, southern Caribbean. In particular, coral barnacles (Pyrgomatidae), boring mussels (Mytilidae: Leiosolenus spp.), gall crabs (Cryptochiridae), and Christmas tree worms (Serpulidae: Spirobranchus spp.) were recorded together with their host corals by means of a photo survey at four depths (5, 10, 15, 20 m) and across seven sites with high and five sites with low eutrophication values (based on δ15N isotope data). Feather duster worms (Sabellidae: Anamobaea), coral blennies (Chaenopsidae: Acanthemblemaria), and worm snails (Vermetidae: Petaloconchus) were insufficiently abundant for thorough quantitative analyses. The results show a decrease in the number of barnacles and Christmas tree worms per host over depth, which could be related to the availability of their host corals. Sites with high δ15N values show a higher abundance of barnacles and Christmas tree worms per host than sites with low values. This indicates that eutrophication could be favourable for these filter feeding organisms but when their densities become too high, they tend to overgrow their hosts and may become a threat to them.


Assuntos
Antozoários , Braquiúros , Thoracica , Animais , Curaçao , Recifes de Corais , Região do Caribe , Biodiversidade , Peixes
17.
Arthropod Struct Dev ; 70: 101190, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35785583

RESUMO

Specialized morphology of diverse parasitic crustaceans reflects their adaptations to an endoparasitic lifestyle. Rhizocephalan barnacles are one of the most highly modified obligatory parasites of other crustaceans. Comprehension of the functional morphology of rhizocephalans could elucidate the main evolutionary trends not only inside parasitic barnacles, but in parasitism as a whole. Despite that, the available morphological information on the rhizocephalans is very fragmented. In this study, we examined the organization and ultrastructural features in different parts of the interna of Peltogaster reticulata (fam. Peltogastridae). The main trunk cuticle is much thicker than that of the side branches due to the different functions of these body parts. The central lumen in the main trunk is lined by an extracellular matrix, while the side branches are not. Muscular fibers are only present in the body wall of the main trunk, where they are organized as a "wicker basket". Furthermore, functional differentiation can be found at the ultrastructural level in the cells of the rootlets: there are distinct cell types both in hypodermal and axial cell layers. The rootlets of P. reticulata are covered by a network of the host's neurons and capillaries.


Assuntos
Thoracica , Animais , Interações Hospedeiro-Parasita , Thoracica/anatomia & histologia
18.
J Exp Biol ; 225(8)2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35389496

RESUMO

Crustacean filter feeders capture oil droplets with the use of their ramified appendages. These appendages behave as paddles or sieves, based on the system's Reynolds number. Here, we used high-speed videography, scanning electron microscopy and fluid mechanics to study the capturing mechanisms of crude oil droplets and the filtering appendage's wettability by two species of barnacles (Balanus glandula and Balanus crenatus) and of the freshwater cladoceran Daphnia magna. Our results show that barnacle appendages behave as paddles and capture droplets in their boundary layers at low Reynolds number. At high Reynolds number, droplets are most likely to be captured via direct interception. There is an intermediate range of Reynolds number where droplets can be captured by both mechanisms at the same time. Daphnia magna captures droplets in the boundary layers of the third and fourth pair of thoracic legs with a metachronal motion of the appendages. All studied surfaces were revealed to be highly lipophobic, demonstrating captured oil droplets with high contact angles. We also discuss implications of such capture mechanisms and wettability on potential ingestion of crude oil by filter feeders. These results further our understanding of the capture of crude oil by filter feeders, shedding light on the main entry point of oil in marine food webs.


Assuntos
Poluição por Petróleo , Petróleo , Thoracica , Animais , Daphnia , Cadeia Alimentar
19.
Mater Today Bio ; 14: 100256, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35469253

RESUMO

In nature, barnacles and bacterial biofilms utilize self-assembly amyloid to achieve strong and robust interface adhesion. However, there is still a lack of sufficient research on the construction of macroscopic adhesives based on amyloid-like nanostructures through reasonable molecular design. Here, we report a genetically programmed self-assembly living-cell bioadhesive inspired by barnacle and curli system. Firstly, the encoding genes of two natural adhesion proteins (CsgA and cp19k) derived from E. coli curli and barnacle cement were fused and expressed as a fundamental building block of the bioadhesive. Utilizing the natural curli system of E. coli, fusion protein can be delivered to cell surface and self-assemble into an amyloid nanofibrous network. Then, the E. coli cells were incorporated into the molecular chain network of xanthan gum (XG) through covalent conjugation to produce a living-cell bioadhesive. The shear adhesive strength of the bioadhesive to the surface of the aluminum sheet reaches 278 â€‹kPa. Benefiting from living cells encapsulated inside, the bioadhesive can self-regenerate with adequate nutrients. This adhesive has low toxicity to organisms, strong resistance to the liquid environment in vivo, easy to pump, exhibiting potential application prospects in biomedical fields such as intestinal soft tissue repair.

20.
Environ Pollut ; 305: 119297, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35421552

RESUMO

Microplastics (MPs) are a global environmental concern and pose a serious threat to marine ecosystems. This study aimed to determine the abundance and distribution of MPs in beach sediments (12 beaches), marine biota (6 beaches) and the influence of microbes on MPs degradation in eco-sensitive Palk Bay and Gulf of Mannar coast. The mean MP abundance 65.4 ± 39.8 particles/m2 in beach sediments; 0.19 ± 1.3 particles/individual fish and 0.22 ± 0.11 particles g-1 wet weight in barnacles. Polyethylene fragments (33.4%) and fibres (48%) were the most abundant MPs identified in sediments and finfish, respectively. Histopathological examination of fish has revealed health consequences such as respiratory system damage, epithelial degradation and enterocyte vacuolization. In addition, eight bacterial and seventeen fungal strains were isolated from the beached MPs. The results also indicated weathering of MPs due to microbial interactions. Model simulations helped in tracking the fate and transboundary landfall of spilled MPs across the Indian Ocean coastline after the X-Press Pearl disaster. Due to regional circulations induced by the monsoonal wind fields, a potential dispersal of pellets has occurred along the coast of Sri Lanka, but no landfall and ecological damage are predicted along the coast of India.


Assuntos
Desastres , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental , Peixes , Sedimentos Geológicos , Índia , Microplásticos , Plásticos , Poluentes Químicos da Água/análise
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