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1.
Environ Pollut ; 279: 116912, 2021 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-33751941

RÉSUMÉ

To understand the fate of plastic in oceans and the interaction with marine organisms, we investigated the incorporation of (bio)polymers and microplastics in selected benthic foraminiferal species by applying FTIR (Fourier Transform Infrared) microscopy. This experimental methodology has been applied to cultured benthic foraminifera Rosalina globularis, and to in situ foraminifera collected in a plastic remain found buried into superficial sediment in the Mediterranean seafloor, Rosalina bradyi, Textularia bocki and Cibicidoides lobatulus. In vitro foraminifera were treated with bis-(2-ethylhexyl) phthalate (DEHP) molecule to explore its internalization in the cytoplasm. Benthic foraminifera are marine microbial eukaryotes, sediment-dwelling, commonly short-lived and with reproductive cycles which play a central role in global biogeochemical cycles of inorganic and organic compounds. Despite the recent advances and investigations into the occurrence, distribution, and abundance of plastics, including microplastics, in marine environments, there remain relevant knowledge gaps, particularly on their effects on the benthic protists. No study, to our knowledge, has documented the molecular scale effect of plastics on foraminifera. Our analyses revealed three possible ways through which plastic-related molecules and plastic debris can enter a biogeochemical cycle and may affect the ecosystems: 1) foraminifera in situ can grow on plastic remains, namely C. lobatulus, R. bradyi and T. bocki, showing signals of oxidative stress and protein aggregation in comparison with R. globularis cultured in negative control; 2) DEHP can be incorporated in the cytoplasm of calcareous foraminifera, as observed in R. globularis; 3) microplastic debris, identified as epoxy resin, can be found in the cytoplasm and the agglutinated shell of T. bocki. We hypothesize that plastic waste and their associated additives may produce modifications related to the biomineralization process in foraminifera. This effect would be added to those induced by ocean acidification with negative consequences on the foraminiferal biogenic carbon (C) storage capacity.


Sujet(s)
Foraminifera , Polluants chimiques de l'eau , Écosystème , Surveillance de l'environnement , Sédiments géologiques , Concentration en ions d'hydrogène , Océans et mers , Matières plastiques , Polymères , Eau de mer , Analyse spectrale
2.
Mar Pollut Bull ; 163: 111933, 2021 Feb.
Article de Anglais | MEDLINE | ID: mdl-33484989

RÉSUMÉ

This paper aims to compare two foraminiferal based biotic indices generally used to evaluate the ecological quality status (EcoQS): the Foram-AMBI and the Foram Stress Index (FSI). For this purpose, we report the distribution and diversity of living foraminiferal assemblages and the environmental variables from a bathymetric transect in the Southern Adriatic Sea. The two indices agree well with the detected organic enrichment but indicate conflicting EcoQS as the Foram-AMBI detects good environmental conditions, whereas the FSI describes a poor-moderate quality. Many species not assigned (including soft-shelled foraminifera) are to blame for the different results. Also, both foraminiferal-based indices neglect the heavy metal increase encountered in the deepest stations. These findings suggest the need for a more in-depth analysis to improve the ecological status evaluation of marine benthic systems, including other descriptors as chemical pollutants in combination with biotic indices sensitive to organic matter enrichment.


Sujet(s)
Polluants environnementaux , Foraminifera , Métaux lourds , Écosystème , Surveillance de l'environnement , Sédiments géologiques , Métaux lourds/analyse
3.
Mar Environ Res ; 162: 105150, 2020 Dec.
Article de Anglais | MEDLINE | ID: mdl-32992223

RÉSUMÉ

Cigarette butts are the most common form of litter in the world and their environmental impact is related to both persistence and potential toxic effects for chemical composition. The objective of this study was to assess the acute toxicity (LC50-48 h) of human-smoked cigarette butts leachate on 3 cultured genera of benthic foraminifera: the calcareous perforate Rosalina globularis, the calcareous imperforate Quinqueloculina spp., and the agglutinated Textularia agglutinans. The specimens were exposed to 16, 8, 4, 2, and 1 cigarette butts/L concentrations that prove to be acutely toxic to all taxa. Starting from 4 cigarette butts/L, both calcareous genera showed shell decalcification, and death of almost all the individuals, except for the more resistant agglutinated species. These results suggest the potential harmfulness of cigarette butts leachate related to pH reduction and release of toxic substances, in particular nicotine, which leads to physiology alteration and in many cases cellular death.


Sujet(s)
Foraminifera , Produits du tabac , Humains , Fumer
4.
J Med Virol ; 85(1): 105-9, 2013 Jan.
Article de Anglais | MEDLINE | ID: mdl-23073996

RÉSUMÉ

Testicular germ cell tumors account for about 1% of all cancers. The incidence of these tumors is increasing and they represent the most common solid malignancies of young men aged 15-40 years with seminoma being one of the most common histotype. Pathogenesis of testicular germ cell tumors remains unknown and, although cryptorchidism is considered the main risk factor, there is evidence of an association with environmental and genetic risk factors. Human papillomaviruses (HPV) are a family of DNA viruses and represent a major risk factor for cervical cancer. In addition, they have been associated with other human non-malignant and malignant diseases, including breast and head and neck cancer. HPV sequences have been detected throughout the male lower genitourinary tract as well as in seminal fluid and an increased testicular tumorigenesis has been reported in HPV transgenic mice. Aim of this study was to evaluate the potential involvement of HPV in human testicular tumorigenesis. Real-time PCR employing GP5+/GP6+ consensus HPV primers was used to examine the presence of HPV sequences in a subset of human seminoma (n = 61) and normal testicles (n = 23). None of the specimens tested displayed the presence of HPV DNA. These findings do not support an association between HPV and human seminoma and warrant further studies to assess definitively the role of these viruses in human testicular tumorigenesis.


Sujet(s)
Papillomaviridae/isolement et purification , Infections à papillomavirus/complications , Infections à papillomavirus/virologie , Séminome/étiologie , Séminome/virologie , Animaux , Amorces ADN/génétique , Humains , Mâle , Souris , Souris transgéniques , Papillomaviridae/génétique , Réaction de polymérisation en chaîne/méthodes , Protéines virales structurales/génétique
5.
PLoS One ; 5(8): e11832, 2010 Aug 02.
Article de Anglais | MEDLINE | ID: mdl-20689848

RÉSUMÉ

Deep-sea ecosystems represent the largest biome of the global biosphere, but knowledge of their biodiversity is still scant. The Mediterranean basin has been proposed as a hot spot of terrestrial and coastal marine biodiversity but has been supposed to be impoverished of deep-sea species richness. We summarized all available information on benthic biodiversity (Prokaryotes, Foraminifera, Meiofauna, Macrofauna, and Megafauna) in different deep-sea ecosystems of the Mediterranean Sea (200 to more than 4,000 m depth), including open slopes, deep basins, canyons, cold seeps, seamounts, deep-water corals and deep-hypersaline anoxic basins and analyzed overall longitudinal and bathymetric patterns. We show that in contrast to what was expected from the sharp decrease in organic carbon fluxes and reduced faunal abundance, the deep-sea biodiversity of both the eastern and the western basins of the Mediterranean Sea is similarly high. All of the biodiversity components, except Bacteria and Archaea, displayed a decreasing pattern with increasing water depth, but to a different extent for each component. Unlike patterns observed for faunal abundance, highest negative values of the slopes of the biodiversity patterns were observed for Meiofauna, followed by Macrofauna and Megafauna. Comparison of the biodiversity associated with open slopes, deep basins, canyons, and deep-water corals showed that the deep basins were the least diverse. Rarefaction curves allowed us to estimate the expected number of species for each benthic component in different bathymetric ranges. A large fraction of exclusive species was associated with each specific habitat or ecosystem. Thus, each deep-sea ecosystem contributes significantly to overall biodiversity. From theoretical extrapolations we estimate that the overall deep-sea Mediterranean biodiversity (excluding prokaryotes) reaches approximately 2805 species of which about 66% is still undiscovered. Among the biotic components investigated (Prokaryotes excluded), most of the unknown species are within the phylum Nematoda, followed by Foraminifera, but an important fraction of macrofaunal and megafaunal species also remains unknown. Data reported here provide new insights into the patterns of biodiversity in the deep-sea Mediterranean and new clues for future investigations aimed at identifying the factors controlling and threatening deep-sea biodiversity.


Sujet(s)
Biodiversité , Animaux , Classification , Mer Méditerranée
6.
Diagn Microbiol Infect Dis ; 59(1): 81-4, 2007 Sep.
Article de Anglais | MEDLINE | ID: mdl-17532594

RÉSUMÉ

We report an unusual case of documented Bartonella henselae genotype I from hepatic tissue in an Italian immunocompetent girl presenting with erythema nodosum and hepatic granulomata. Polymerase chain reaction (PCR) was performed on biopsied liver sample to confirm the etiologic role of B. henselae and to identify the genetic variant of this organism. A PCR on the same liver biopsy for parvovirus B19 was also positive, but the clinical meaning of this was not clear.


Sujet(s)
Infections à Bartonella/diagnostic , Bartonella henselae/génétique , Érythème noueux/étiologie , Parvovirus humain B19/génétique , Antibactériens/usage thérapeutique , Infections à Bartonella/complications , Infections à Bartonella/traitement médicamenteux , Bartonella henselae/classification , Enfant d'âge préscolaire , Clarithromycine/usage thérapeutique , Érythème noueux/traitement médicamenteux , Femelle , Granulome/traitement médicamenteux , Granulome/microbiologie , Humains , Immunocompétence , Maladies du foie/traitement médicamenteux , Maladies du foie/microbiologie , Infections à Parvoviridae/complications , Infections à Parvoviridae/diagnostic , Infections à Parvoviridae/génétique , Réaction de polymérisation en chaîne
7.
Herpes ; 13(3): 72-4, 2006 Nov.
Article de Anglais | MEDLINE | ID: mdl-17147911

RÉSUMÉ

A case of primary infection by human herpesvirus 6 (HHV-6) variant A in a 54-year-old woman, which occurred at the same time as the onset of encephalomyelitis, is reported. The correlation between the two events is discussed. It is speculated that, during the early phase of the infection, the HHV-6 spread to the central nervous system and triggered a pathogenic process that initially developed without symptoms. When the neurological disorders appeared, HHV-6 had already established a latent state: only the virus carried by infected blood cells was detected in the cerebrospinal fluid.


Sujet(s)
Encéphalomyélite/virologie , Herpèsvirus humain de type 6/classification , Herpèsvirus humain de type 6/isolement et purification , Infections à roséolovirus/complications , Vertèbres cervicales/imagerie diagnostique , ADN viral/sang , ADN viral/liquide cérébrospinal , Encéphalomyélite/imagerie diagnostique , Femelle , Variation génétique , Herpèsvirus humain de type 6/génétique , Humains , Adulte d'âge moyen , Radiographie , Infections à roséolovirus/imagerie diagnostique , Infections à roséolovirus/virologie
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