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1.
PLoS One ; 19(4): e0298668, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38625919

RESUMEN

Limax maximus, or great gray slug, is a common agriculture pest. The pest infests crops during their growth phase, creating holes in vegetable leaves, particularly in seedlings and tender leaves. A study was conducted to assess the insecticidal activity of Ageratina adenophora extract against these slugs. Factors such as fecundity, growth, hatching rate, offspring survival rate, protective enzyme activity, and detoxifying enzyme activity were examined in slugs exposed to the extract's sublethal concentration (LC50) for two different durations (24 and 48 h). The phytochemical variability of the extracts was also studied. The LC50 value of the A. adenophora extract against L. maximus was 35.9 mg/mL. This extract significantly reduced the hatching rate of eggs and the survival rate of offspring hatched from exposed eggs compared with the control. The lowest rates were observed in those exposed for 48 h. The survival, growth, protective enzyme, and detoxification activity of newly hatched and 40-day-old slugs decreased. The A. adenophora extract contained tannins, flavonoids, and saponins, possibly contributing to their biological effects. These results suggest that the extract could be used as an alternative treatment for slug extermination, effectively controlling this species.


Asunto(s)
Ageratina , Asteraceae , Gastrópodos , Insecticidas , Animales , Insecticidas/farmacología , Moluscos , Extractos Vegetales/farmacología
2.
Proc Natl Acad Sci U S A ; 121(14): e2311597121, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38527199

RESUMEN

Warmer temperatures and higher sea level than today characterized the Last Interglacial interval [Pleistocene, 128 to 116 thousand years ago (ka)]. This period is a remarkable deep-time analog for temperature and sea-level conditions as projected for 2100 AD, yet there has been no evidence of fossil assemblages in the equatorial Atlantic. Here, we report foraminifer, metazoan (mollusks, bony fish, bryozoans, decapods, and sharks among others), and plant communities of coastal tropical marine and mangrove affinities, dating precisely from a ca. 130 to 115 ka time interval near the Equator, at Kourou, in French Guiana. These communities include ca. 230 recent species, some being endangered today and/or first recorded as fossils. The hyperdiverse Kourou mollusk assemblage suggests stronger affinities between Guianese and Caribbean coastal waters by the Last Interglacial than today, questioning the structuring role of the Amazon Plume on tropical Western Atlantic communities at the time. Grassland-dominated pollen, phytoliths, and charcoals from younger deposits in the same sections attest to a marine retreat and dryer conditions during the onset of the last glacial (ca. 110 to 50 ka), with a savanna-dominated landscape and episodes of fire. Charcoals from the last millennia suggest human presence in a mosaic of modern-like continental habitats. Our results provide key information about the ecology and biogeography of pristine Pleistocene tropical coastal ecosystems, especially relevant regarding the-widely anthropogenic-ongoing global warming.


Asunto(s)
Ecosistema , Moluscos , Humanos , Animales , Guyana Francesa , Plantas , Polen , Fósiles
3.
Small ; 20(5): e2304183, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37759411

RESUMEN

Mollusks, as well as many other living organisms, have the ability to shape mineral crystals into unconventional morphologies and to assemble them into complex functional mineral-organic structures, an observation that inspired tremendous research efforts in scientific and technological domains. Despite these, a biochemical toolkit that accounts for the formation of the vast variety of the observed mineral morphologies cannot be identified yet. Herein, phase-field modeling of molluscan nacre formation, an intensively studied biomineralization process, is used to identify key physical parameters that govern mineral morphogenesis. Manipulating such parameters, various nacre properties ranging from the morphology of a single mineral building block to that of the entire nacreous assembly are reproduced. The results support the hypothesis that the control over mineral morphogenesis in mineralized tissues happens via regulating the physico-chemical environment, in which biomineralization occurs: the organic content manipulates the geometric and thermodynamic boundary conditions, which in turn, determine the process of growth and the form of the biomineral phase. The approach developed here has the potential of providing explicit guidelines for the morphogenetic control of synthetically formed composite materials.


Asunto(s)
Nácar , Animales , Nácar/química , Minerales/química , Moluscos , Biomineralización , Fenómenos Físicos , Carbonato de Calcio/química
4.
Environ Res ; 212(Pt C): 113370, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35504343

RESUMEN

One of the most common environmental pollutant in aquatic ecosystems are polypropylene microplastics and their impacts on aquatic organisms are still scarce. The study aimed to prepare polypropylene microplastics using organic solvent (spherical and 11.86-44.62 µm) and then test their toxicity on the freshwater benthic mollusc grazer Pomaceae paludosa. The present study investigated chronic (28 days) exposure of polypropylene microplastics via dietary supplements (250 mg kg-1, 500 mg kg-1 & 750 mg kg-1) in P. paludosa, and the toxic effect was evaluated in digestive gland tissue. The FTIR results revealed no change in polypropylene microplastics during ingestion or after egestion. On the other hand, Ingestion causes accumulation in their bodies and disrupts redox homeostasis. Meanwhile, alteration occurs in oxidative stress-related biomarkers such as increased reactive oxygen species level (ROS), impaired the biochemical parameters of antioxidant system catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), and glutathione - S- transferase (GST), deterioration of oxidative stress effects in lipid peroxidation (LPO) and carbonyl protein (CP) and changed the digestive enzymes such as amylase, pepsin, esterase and alkaline phosphatase that are measured in hepatopancreas tissue. The histology results revealed that ingesting these microplastics caused severe damage to the digestive gland cells. According to the findings, ingestion of polypropylene microplastics in benthic freshwater mollusc causes more serious harm and impacts energy acquisition. This finding represents the ecological risk of polypropylene microplastic pollution in the freshwater ecosystem.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Ecosistema , Agua Dulce , Glutatión Transferasa/metabolismo , Moluscos/metabolismo , Estrés Oxidativo , Plásticos/metabolismo , Plásticos/toxicidad , Polipropilenos/metabolismo , Polipropilenos/toxicidad , Contaminantes Químicos del Agua/química
5.
Nature ; 597(7876): 360-365, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34526707

RESUMEN

Fish and other aquatic foods (blue foods) present an opportunity for more sustainable diets1,2. Yet comprehensive comparison has been limited due to sparse inclusion of blue foods in environmental impact studies3,4 relative to the vast diversity of production5. Here we provide standardized estimates of greenhouse gas, nitrogen, phosphorus, freshwater and land stressors for species groups covering nearly three quarters of global production. We find that across all blue foods, farmed bivalves and seaweeds generate the lowest stressors. Capture fisheries predominantly generate greenhouse gas emissions, with small pelagic fishes generating lower emissions than all fed aquaculture, but flatfish and crustaceans generating the highest. Among farmed finfish and crustaceans, silver and bighead carps have the lowest greenhouse gas, nitrogen and phosphorus emissions, but highest water use, while farmed salmon and trout use the least land and water. Finally, we model intervention scenarios and find improving feed conversion ratios reduces stressors across all fed groups, increasing fish yield reduces land and water use by up to half, and optimizing gears reduces capture fishery emissions by more than half for some groups. Collectively, our analysis identifies high-performing blue foods, highlights opportunities to improve environmental performance, advances data-poor environmental assessments, and informs sustainable diets.


Asunto(s)
Acuicultura , Ecosistema , Monitoreo del Ambiente , Alimentos Marinos , Desarrollo Sostenible , Animales , Acuicultura/tendencias , Cambio Climático , Dieta , Ecología , Política Ambiental , Explotaciones Pesqueras , Abastecimiento de Alimentos/métodos , Gases de Efecto Invernadero , Humanos , Moluscos , Nitrógeno , Fósforo , Alimentos Marinos/provisión & distribución , Algas Marinas , Desarrollo Sostenible/tendencias
6.
Int J Mol Sci ; 21(22)2020 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-33198405

RESUMEN

Gonadotropin-releasing hormones (GnRHs) play pivotal roles in reproduction via the hypothalamus-pituitary-gonad axis (HPG axis) in vertebrates. GnRHs and their receptors (GnRHRs) are also conserved in invertebrates lacking the HPG axis, indicating that invertebrate GnRHs do not serve as "gonadotropin-releasing factors" but, rather, function as neuropeptides that directly regulate target tissues. All vertebrate and urochordate GnRHs comprise 10 amino acids, whereas amphioxus, echinoderm, and protostome GnRH-like peptides are 11- or 12-residue peptides. Intracellular calcium mobilization is the major second messenger for GnRH signaling in cephalochordates, echinoderms, and protostomes, while urochordate GnRHRs also stimulate cAMP production pathways. Moreover, the ligand-specific modulation of signal transduction via heterodimerization between GnRHR paralogs indicates species-specific evolution in Ciona intestinalis. The characterization of authentic or putative invertebrate GnRHRs in various tissues and their in vitro and in vivo activities indicate that invertebrate GnRHs are responsible for the regulation of both reproductive and nonreproductive functions. In this review, we examine our current understanding of and perspectives on the primary sequences, tissue distribution of mRNA expression, signal transduction, and biological functions of invertebrate GnRHs and their receptors.


Asunto(s)
Hipotálamo/metabolismo , Invertebrados/metabolismo , Receptores LHRH/metabolismo , Animales , Evolución Biológica , Células COS , Calcio/metabolismo , Chlorocebus aethiops , Ciona intestinalis , AMP Cíclico/metabolismo , Equinodermos , Femenino , Hormona Liberadora de Gonadotropina/metabolismo , Células HEK293 , Humanos , Ligandos , Masculino , Cadenas de Markov , Moluscos , Transducción de Señal , Distribución Tisular , Urocordados
7.
Mar Drugs ; 18(11)2020 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-33228163

RESUMEN

Respiratory diseases place an immense burden on global health and there is a compelling need for the discovery of new compounds for therapeutic development. Here, we identify research priorities by critically reviewing pre-clinical and clinical studies using extracts and compounds derived from molluscs, as well as traditional molluscan medicines, used in the treatment of respiratory diseases. We reviewed 97 biomedical articles demonstrating the anti-inflammatory, antimicrobial, anticancer, and immunomodulatory properties of >320 molluscan extracts/compounds with direct relevance to respiratory disease, in addition to others with promising bioactivities yet to be tested in the respiratory context. Of pertinent interest are compounds demonstrating biofilm inhibition/disruption and antiviral activity, as well as synergism with approved antimicrobial and chemotherapeutic agents. At least 100 traditional medicines, incorporating over 300 different mollusc species, have been used to treat respiratory-related illness in cultures worldwide for thousands of years. These medicines provide useful clues for the discovery of bioactive components that likely underpin their continued use. There is particular incentive for investigations into anti-inflammatory compounds, given the extensive application of molluscan traditional medicines for symptoms of inflammation, and shells, which are the principal molluscan product used in these preparations. Overall, there is a need to target research toward specific respiratory disease-related hypotheses, purify bioactive compounds and elucidate their chemical structures, and develop an evidence base for the integration of quality-controlled traditional medicines.


Asunto(s)
Antiinflamatorios/aislamiento & purificación , Moluscos/química , Enfermedades Respiratorias/tratamiento farmacológico , Animales , Antiinflamatorios/farmacología , Antivirales/aislamiento & purificación , Antivirales/farmacología , COVID-19 , Infecciones por Coronavirus/complicaciones , Descubrimiento de Drogas , Humanos , Inflamación/tratamiento farmacológico , Medicina Tradicional , Pandemias , Neumonía Viral/complicaciones
8.
PLoS One ; 15(9): e0235588, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32946457

RESUMEN

Data on the historical change of the Transbaikalian malacofauna in the Neopleistocene and Holocene is presented. Aquatic mollusc shells from archaeological excavations of the ancient settlements dating from the Neolithic period to Medieval and also from a drill hole of the Neopleistocene alluvial deposits were collected. In total eight species of bivalve molluscs from the families Margaritiferidae, Unionidae, Lymnocardiidae, Glycymerididae [marine], and two gastropod species from families Viviparidae and Planorbidae were identified. These species were aged using radiocarbon dating. It was found that the species ranged in age from more than 50.000 to 2.080-1.210 years BP. Five species inhabited the Transbaikal region which are locally extirpated today. Their disjunctive ranges in the past included southern Europe and Western and Eastern Siberia to Transbaikalia and in the east to Far East and Primorye Territory of Russia. A remarkable finding is that of the bivalve genus Monodacna, which was found very far from its native range, the Ponto-Caspian region. The time of existence and extirpation of the thermophilic species of genera Monodacna, Planorbis, Lanceolaria and Amuropaludina corresponds to cycles of the warming and cooling in Pleistocene and Holocene according to regional climate chronological scales. These species can be used as palaeoclimate indicators. Change of the regional malacofaunal species composition is connected with the natural climatochron cycles in the Pleistocene and Holocene resulting in evidence for succession. In the course of this succession, these stenothermal species became extirpated on a regional level, decreasing their global ranges.


Asunto(s)
Distribución Animal , Organismos Acuáticos/fisiología , Biodiversidad , Ecología/métodos , Moluscos/fisiología , Exoesqueleto/química , Animales , Organismos Acuáticos/química , Organismos Acuáticos/clasificación , Arqueología , Europa (Continente) , Asia Oriental , Fósiles , Agua Dulce , Geografía , Historia Antigua , Moluscos/química , Moluscos/clasificación , Datación Radiométrica , Siberia
9.
Genomics ; 112(6): 3991-3999, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32650091

RESUMEN

The gastropod mollusk Limax flavus, one of the most widespread pests in China, is used to treat infectious diseases in traditional Chinese medicine. However, little genomic information is available for this non-model species. In this study, the whole-body transcriptome of L. flavus was sequenced using next generation sequencing technology. A total of 6.81 Gb clean reads were obtained, which were assembled into 150,766 transcripts with 132,206 annotated unigenes. Functionally classification assigned 30,542 unigenes to 56 Gene Ontology terms, 16,745 unigenes were divided into 26 euKaryotic Ortholog Groups of proteins categories, and 13,854 unigenes were assigned to 230 Kyoto Encyclopedia of Genes and Genomes pathways. Furthermore, we identified 17,251 simple sequence repeats and several kinds of antimicrobial peptide and protein (AMPs) genes. The transcriptome data of L. flavus will provide a valuable genomic resource for further studies on this species, and the AMPs identified in L. flavus will support its medical potential.


Asunto(s)
Moluscos/genética , Proteínas Citotóxicas Formadoras de Poros/farmacología , Transcriptoma , Animales , Moluscos/metabolismo
10.
Nat Commun ; 11(1): 2006, 2020 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-32332739

RESUMEN

How climate and ecology affect key cultural transformations remains debated in the context of long-term socio-cultural development because of spatially and temporally disjunct climate and archaeological records. The introduction of agriculture triggered a major population increase across Europe. However, in Southern Scandinavia it was preceded by ~500 years of sustained population growth. Here we show that this growth was driven by long-term enhanced marine production conditioned by the Holocene Thermal Maximum, a time of elevated temperature, sea level and salinity across coastal waters. We identify two periods of increased marine production across trophic levels (P1 7600-7100 and P2 6400-5900 cal. yr BP) that coincide with markedly increased mollusc collection and accumulation of shell middens, indicating greater marine resource availability. Between ~7600-5900 BP, intense exploitation of a warmer, more productive marine environment by Mesolithic hunter-gatherers drove cultural development, including maritime technological innovation, and from ca. 6400-5900 BP, underpinned a ~four-fold human population growth.


Asunto(s)
Arqueología , Clima , Evolución Cultural/historia , Recursos Naturales/provisión & distribución , Crecimiento Demográfico , Agricultura , Animales , Historia Antigua , Humanos , Invenciones/historia , Moluscos , Océanos y Mares , Países Escandinavos y Nórdicos
11.
PLoS One ; 15(2): e0228546, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32027712

RESUMEN

A cave site Shelter in Smolen III (southern Poland) contains an approximately 2-m-thick stratified sequence of Upper Pleistocene and Holocene clastic sediments, unique for Central Europe. The sequence contents abundant fossil fauna, including mollusk, rodent and bat remains. The cave sites with long profiles of subfossil fauna present a great value for reconstructions of regional terrestrial paleoenvironment. We explore the stratigraphy of this site through analyses of the lithology and geochemistry of sediments, radiocarbon dating of faunal and human remains and charcoals, and archaeological study, as well as the paleoecology derived from the taxonomic composition of fossil faunal assemblages. Our data show that the entire period of the Holocene is recorded in the rockshelter, which makes that site an exceptional and highly valuable case. We present paleoenvironmental reconstructions of regional importance, and we propose to regard Shelter in Smolen III as a regional stratigraphic stratotype of Holocene clastic cave sediments.


Asunto(s)
Arqueología/métodos , Cuevas/química , Sedimentos Geológicos/análisis , Paleontología/métodos , Animales , Quirópteros/clasificación , Clasificación , Bases de Datos Factuales , Europa (Continente) , Fósiles/patología , Historia Antigua , Humanos , Moluscos/clasificación , Polonia , Roedores/clasificación
12.
Braz. arch. biol. technol ; 63: e20180501, 2020. graf
Artículo en Inglés | LILACS | ID: biblio-1132211

RESUMEN

Abstract Mesenchymal stem cells and osteoblasts play important roles in bone formation. Achatina fulica mucus presented the property of osteoinduction. This study aimed to examine the effects of A. fulica mucus on human mesenchymal stem cell (hMSC) and human fetal osteoblastic cell line (HFOB) differentiation. The integrated effects of A. fulica mucus and polycaprolactone (PCL) on the differentiation of hMSCs were tested. The cell viability of hMSCs treated with A. fulica mucus was investigated by the MTT assay. The cell mineralization was observed by Alizarin Red S staining, the gene expression was investigated using RT-PCR, and the PI3K activation was studied using flow cytometry. The results indicated that A. fulica mucus induced osteogenic differentiation in hMSCs and HFOBs by upregulation of the osteogenic markers; osteopontin (OPN) and osteocalcin (OCN). The results of the Alizarin Red S staining indicated that A. fulica mucus supported mineralization in both hMSCs and HFOBs. The hMSCs cultured on PCL supplemented with A. fulica mucus showed significantly increased RUNX2 and OPN expressions. A. fulica mucus was observed to increase PI3K activation in hMSCs. The findings of this study suggested that A. fulica mucus and biomaterials could be applied together for use in bone regeneration in the future.


Asunto(s)
Humanos , Animales , Osteogénesis/fisiología , Regeneración Ósea , Células Madre Mesenquimatosas/citología , Moluscos/química , Moco/química , Pruebas de Toxicidad , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Citometría de Flujo
13.
J Mol Biol ; 431(22): 4381-4407, 2019 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-31442478

RESUMEN

Selenoproteins typically contain a single selenocysteine, the 21st amino acid, encoded by a context-redefined UGA. However, human selenoprotein P (SelenoP) has a redox-functioning selenocysteine in its N-terminal domain and nine selenium transporter-functioning selenocysteines in its C-terminal domain. Here we show that diverse SelenoP genes are present across metazoa with highly variable numbers of Sec-UGAs, ranging from a single UGA in certain insects, to 9 in common spider, and up to 132 in bivalve molluscs. SelenoP genes were shaped by a dynamic evolutionary process linked to selenium usage. Gene evolution featured modular expansions of an ancestral multi-Sec domain, which led to particularly Sec-rich SelenoP proteins in many aquatic organisms. We focused on molluscs, and chose Pacific oyster Magallana gigas as experimental model. We show that oyster SelenoP mRNA with 46 UGAs is translated full-length in vivo. Ribosome profiling indicates that selenocysteine specification occurs with ∼5% efficiency at UGA1 and approaches 100% efficiency at distal 3' UGAs. We report genetic elements relevant to its expression, including a leader open reading frame and an RNA structure overlapping the initiation codon that modulates ribosome progression in a selenium-dependent manner. Unlike their mammalian counterparts, the two SECIS elements in oyster SelenoP (3'UTR recoding elements) do not show functional differentiation in vitro. Oysters can increase their tissue selenium level up to 50-fold upon supplementation, which also results in extensive changes in selenoprotein expression.


Asunto(s)
Codón de Terminación/genética , Moluscos/química , Moluscos/genética , Selenoproteína P/química , Selenoproteína P/genética , Animales , Evolución Biológica , Biosíntesis de Proteínas , Selenocisteína/química , Selenocisteína/genética
14.
Environ Pollut ; 253: 474-487, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31330340

RESUMEN

Anthropogenic activities including coastal industries, urbanization, extensive agriculture and aquaculture as well as their cumulative impacts represent major sources of perturbation of marine coastal systems. Macrobenthic communities are useful ecological indicators for monitoring the health status of marine environments (or polluted environments). The present study reports, for the first time, the response of benthic macrofauna sampled during two years survey (2015-2016) to multiple anthropogenic pressures on the coastal zone south of Sfax (Tunisia). A total of 12 stations were monitored seasonally at locations downstream from the main potential sources of disturbance. 106 macrobenthos taxa, belonging to six animal phyla and 70 families, were identified with a dominance of polychaetes (42%), crustaceans (35%) and molluscs (18%). We used an ANOVA test and cluster analysis to identify spatial gradient linked to environmental and anthropogenic factors, including depth, sedimentary texture and anthropogenic activities (i.e. phosphogypsum discharges).The macrofauna present lowest species number and abundance on stations undergoing anthropogenic inputs, which are extremely polluted by heavy metals (Cd, Cu, F and N) and excess of organic matter. Univariate parameters reveal a general trend of increasing species diversity with increasing distance from the pollution source. The polluted stations are strongly dominated by carnivores, and selective deposit feeders, and more closely linked to the availability of trophic resources than to anthropogenic constraints. The seasonal changes in macrobenthic abundance, diversity indices and community structure are mainly linked to the biological cycle (e.g. recruitment events) of the dominant species. Biotic indices (AMBI and BO2A) classified the coastal zone south of Sfax as moderate and good ecological status. This study suggests that initiating a long-term monitoring programme would improve our understanding of the temporal changes of macrobenthic communities of this ecosystem, contributing to the assessment of effective management and conservation measures in this disturbed area.


Asunto(s)
Organismos Acuáticos/fisiología , Monitoreo del Ambiente , Invertebrados/fisiología , Contaminación del Agua/análisis , Animales , Acuicultura , Sulfato de Calcio , Crustáceos , Ecología , Ecosistema , Contaminantes Ambientales , Mar Mediterráneo , Metales Pesados/análisis , Moluscos , Fósforo , Túnez
15.
PLoS One ; 14(6): e0217596, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31188856

RESUMEN

During the past decade, over 3000 shell middens or shell matrix deposits have been discovered on the Farasan Islands in the southern Red Sea, dating to the period c. 7,360 to 4,700 years ago. Many of the sites are distributed along a palaeoshoreline which is now 2-3 m above present sea level. Others form clusters with some sites on the shoreline and others located inland over distances of c. 30 m to 1 km. We refer to these inland sites as 'post-shore' sites. Following Meehan, who observed a similar spatial separation in shell deposition in her ethnographic study of Anbarra shellgathering in the Northern Territory of Australia, we hypothesise that the shoreline sites are specialised sites for the processing or immediate consumption of shell food, and the post-shore sites are habitation sites used for a variety of activities. We test this proposition through a systematic analysis of 55 radiocarbon dates and measurement of shell quantities from the excavation of 15 shell matrix sites in a variety of locations including shoreline and post-shore sites. Our results demonstrate large differences in rates of shell accumulation between these two types of sites and selective removal of shoreline sites by changes in sea level. We also discuss the wider implications for understanding the differential preservation and visibility of shell-matrix deposits in coastal settings in other parts of the world extending back into the later Pleistocene in association with periods of lowersea level. Our results highlight the importance of taphonomic factors of post-depositional degradation and destruction, rates of shell accumulation, the influence on site location of factors other than shell food supply, and the relative distance of deposits from their nearest palaeoshorelines as key variables in the interpretation of shell quantities. Failure to take these variables into account when investigating shells and shell-matrix deposits in late Pleistocene and early Holocene contexts is likely to compromise interpretations of the role and significance of shell food in human evolutionary and socio-cultural development.


Asunto(s)
Exoesqueleto/química , Dieta Paleolítica/historia , Sedimentos Geológicos/análisis , Moluscos/química , Exoesqueleto/anatomía & histología , Animales , Arqueología/métodos , Historia Antigua , Humanos , Océano Índico , Islas , Moluscos/anatomía & histología , Arabia Saudita
16.
Environ Sci Pollut Res Int ; 26(13): 13522-13538, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30911967

RESUMEN

Skhira Bay located in the Gulf of Gabès, on the southeastern coast of Tunisia, is an important area in terms of its dense vegetation coverage, wide continental shelf, and fisheries resources. However, this area with a typically micro-tidal range is subject to intensive anthropogenic pressures: soft bottom trawling, chemical pollution from phosphoric acid production, and shipping activity. The present study is the first investigation of the structure of the benthic macrofauna on this part of the Tunisian coast. In April 2010, 28 stations were sampled along four transects from the phosphogypsum outfall on an inshore-offshore gradient. A total of 239 macrobenthos taxa, belonging to nine zoological groups and 140 families, were identified with a dominance of polychaetes (33.5%), crustaceans (29.4%), and mollusks (19.6%). Results show that the stations facing the phosphogypsum discharges are the most disturbed and characterized by a poorly diversified macrofauna. The macrofauna is dominated by carnivores, suspension feeders, and selective deposit feeders, and seems to be linked more to the availability of trophic resources than to disturbance. Four benthic assemblages are identified using Cluster and MDS analyses linked to edaphic factors, such as sediment structure, organic matter content, inshore/offshore gradient, and the proximity of the phosphogypsum outfall. The biotic indices (AMBI and BO2A) calculated from macrofauna data show that the ecological status of Skhira Bay varies overall from moderate to good. This study suggests initiating a long-term monitoring program to improve our understanding of the temporal changes of this ecosystem, to recommend the necessary conservation measures in this area of high-value natural heritage.


Asunto(s)
Sulfato de Calcio/química , Crustáceos/química , Sedimentos Geológicos/análisis , Fósforo/química , Animales , Bahías , Ecología , Ecosistema , Sedimentos Geológicos/química , Mar Mediterráneo , Moluscos , Túnez
17.
Sci Rep ; 9(1): 1003, 2019 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-30700797

RESUMEN

Isolated spherical carbonate concretions are frequently observed in finer grained marine sediments of widely varying geological age. Recent studies on various kinds of spherical carbonate (CaCO3) concretions revealed that they formed very rapidly under tightly constrained conditions. However, the formation ages of the isolated spherical carbonate concretions have never been determined. Here we use 87Sr/86Sr ratios to determine the ages of these spherical concretions. The studied concretions formed in the Yatsuo Group of Miocene age in central Japan. Some formed post-mortem around tusk-shells (Fissidentalium spp.), while other concretions have no shell fossils inside. The deformation of sedimentary layers around the concretions, combined with geochemical analyses, reveal that Sr was incorporated into the CaCO3 concretions during their rapid formation. Strontium isotopic stratigraphy using 87Sr/86Sr ratios of all concretions indicates an age of 17.02 ± 0.27 Ma, with higher accuracy than the ages estimated using micro-fossils from the Yatsuo Group. The results imply that the 87Sr/86Sr ratio of isolated spherical carbonate concretions can be applied generally to determine the numerical ages of marine sediments, when concretions formed soon after sedimentation. The 87Sr/86Sr age determinations have high accuracy, even in cases without any fossils evidence.


Asunto(s)
Carbonato de Calcio/análisis , Fósiles/historia , Sedimentos Geológicos/química , Geología , Moluscos/química , Isótopos de Estroncio/análisis , Animales , Historia Antigua , Japón
19.
Pak J Pharm Sci ; 31(4(Supplementary)): 1555-1563, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30058548

RESUMEN

The aim of this study is to explore the presence of antimicrobial bioactive agents in the foot muscle extracts of snails belonging to genus Physa and Ceciloides. Antibacterial activity of foot extracts belonging to species named as P. fontinalis, P. gyrina, P. acuta, C. acicula, C. eulima, C. petitiana, was checked and compared against three bacterial strains i.e. E.coli, P. auroginosa, S. aureus by using disc diffusion method. The results were highly significant with maximum zone of inhibition of 20.10 mm in the P. fontinalis acetone extract and the least was 12.97 mm of C. eulima diethyl ether extract. The microdilution method was employed to observe MIC to evaluate antimicrobial resistance pattern of snails foot muscle extract against three mentioned strains. MIC of foot extracts was ranging from 0.03µ/ml-5 µg/ml for six species. TLC was carried out for profiling of extracts with positive results. Foot extracts from species of both genera eluted in different fractions of compounds with a good resolution in 100% n-hexane and ethyl acetate each. The plates developed in solvent system showed purple and yellow spots indicating the presence proteins and organic compounds showing it a promising canditadate for the therapeutic purposes.


Asunto(s)
Antibacterianos/farmacología , Productos Biológicos/farmacología , Gastrópodos , Músculo Esquelético , Animales , Antibacterianos/aislamiento & purificación , Productos Biológicos/aislamiento & purificación , Evaluación Preclínica de Medicamentos/métodos , Extremidades/fisiología , Gastrópodos/fisiología , Pruebas de Sensibilidad Microbiana/métodos , Moluscos , Músculo Esquelético/fisiología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología
20.
J Ethnopharmacol ; 210: 156-178, 2018 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-28830818

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: This review focuses on traditional and contemporary anti-inflammatory uses of mollusc-derived products summarising all the in vitro, in vivo and human clinical trials that have tested the anti-inflammatory activity of molluscan natural products. Inflammatory conditions, burns and wounds have been an ongoing concern for human health since the early era of civilisation. Many texts from ancient medicine have recorded the symptoms, signs and treatments for these conditions. Natural treatments are well-documented in traditional European medicine, Traditional Chinese Medicine (TCM), Siddha and ancient Mediterranean and African traditional medicine and include a surprisingly large number of molluscan species. MATERIALS AND METHODS: An extensive review of the Materia Medica and scientific literature was undertaken using key word searches for "mollusc" and "anti-inflammatory" or "immunomodulatory" or "wound healing". RESULTS: Molluscs have been used in ethnomedicine by many traditional cultures to treat different aspects of inflammatory conditions. We found 104 different anti-inflammatory preparations from a variety of molluscan species, of which 70 were from the well-documented Traditional Chinese Medicine (TCM). This traditional use of molluscs has driven the testing for inflammatory activity in extracts from some species in the phylum Mollusca, with 20 in vitro studies, 40 in vivo animal studies and 14 human clinical trials performed to substantiate the anti-inflammatory and wound healing activity of molluscs. Some of these studies have led to the approval of mollusc-derived products to be used as over-the-counter (OTC) nutraceuticals, like Lyprinol® and Biolane™ from the New Zealand green lipped mussel Perna canaliculus. CONCLUSION: Natural products provide important leads for the development of pharmaceuticals, including anti-inflammatory agents. Only a small proportion of the molluscan traditional medicines have been tested to confirm their anti-inflammatory activity and most screening studies have tested crude extracts from molluscs without any chemical characterisation. This highlights the need for further research to strategically identify the anti-inflammatory compounds in molluscan medicines to provide leads for novel anti-inflammatory drugs in the future.


Asunto(s)
Antiinflamatorios/farmacología , Factores Inmunológicos/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Antiinflamatorios/aislamiento & purificación , Etnofarmacología , Humanos , Factores Inmunológicos/aislamiento & purificación , Inflamación/tratamiento farmacológico , Medicina Tradicional/métodos , Moluscos
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