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1.
Molecules ; 28(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36838603

RESUMO

In the present work, the microclimatic conditions (temperature (T), relative humidity (RH), and illuminance (I)), together with the air quality (both aerosol particulate matter (PM) and gaseous pollutants), were monitored to evaluate the environmental conditions inside the Santuario della Beata Vergine dei Miracoli in Saronno (VA), a masterpiece of the Italian Renaissance. For this purpose, dataloggers were used to carry out the T, RH, and I measurements, whereas an optical particle counter (OPC) was employed to perform the particle count and determine the concentration of the aerosol PM. Finally, diffusive passive samplers were used to determine the concentration of nitrogen dioxide (NO2) and BTEX (benzene, toluene, ethylbenzene, and xylenes). To identify possible spatial variations, the studies were conducted at different sites and different heights in the Sanctuary. Particular focus was given to the Easter week during which liturgical services attracting large numbers of people were carried out. Additionally, a comparison with the outdoor values was performed to highlight the accumulation phenomena and other variations in the concentrations of the species. Despite the indoor concentrations of pollutants and variations in the thermohygrometric parameters being generally lower compared to the outdoors (e.g., 5.2-15.0 µg m-3 versus 17.7-45.3 µg m-3 for NO2), the microclimatic conditions were often not in line with the Italian legislation and technical standards.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluição do Ar , Poluentes Ambientais , Humanos , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Dióxido de Nitrogênio , Monitoramento Ambiental , Poluição do Ar/análise , Material Particulado/análise
2.
Vaccines (Basel) ; 10(11)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36366380

RESUMO

(1) Background: this study investigated the preventive measures implemented in the workplace and evaluated knowledge, attitudes and adherence behaviors regarding SARS-CoV-2 routes of transmission and preventive measures in a group of workers. (2) Methods: this cross-sectional study was conducted from May to July 2021 among 501 workers in the Campania region, in Southern Italy. (3) Results: 80.5% of respondents declared that their company had implemented the main COVID-19 preventive measures, and 54.7% of respondents knew SARS-CoV-2 routes of transmission along with the main preventive measures. Moreover, 34.2% were highly concerned about contracting SARS-CoV-2 in the workplace and transmitting it to family. Adherence to all preventive measures in the workplace involved 42.5% of respondents. The results of the multivariate logistic regression model revealed that significant determinants of adherence to all preventive measures in the workplace were being female, working not as a manager or office employee, cohabiting with someone that received a diagnosis of SARS-CoV-2 infection, knowing SARS-CoV-2 routes of transmission and the related main preventive measures, being highly concerned of contracting SARS-CoV-2 in the workplace and transmitting it to family and believing that COVID-19 vaccine offers high protection against disease. At the time of the survey, 47.5% of respondents had already received COVID-19 vaccine. Among unvaccinated respondents, 11.8% expressed unwillingness to get vaccinated for COVID-19. (4) Conclusions: These findings highlighted a good awareness about COVID-19 prevention and underlined a good propensity to get vaccinated among workers. Therefore, there is the need that preventive measures should be prioritized in the working context.

3.
Vaccines (Basel) ; 10(5)2022 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-35632429

RESUMO

BACKGROUND: This study explored the extent of COVID-19 vaccination coverage and investigated drivers and barriers to COVID-19 vaccine uptake among people in prison. METHODS: This cross-sectional study was conducted from July to October 2021 among 517 detained people in the Campania region of South Italy. RESULTS: In total, 47.1% of participants expressed a high concern about contracting COVID-19 after vaccination, whereas 60.6% and 53.8% of respondents reported a positive attitude towards usefulness and safety of COVID-19 vaccines, respectively. Adherence to the active offer of COVID-19 vaccination involved 89.7% of detained subjects. COVID-19 vaccination uptake was significantly higher in females, and in those who reported influenza vaccination uptake, had received information about COVID-19 vaccination from media and newspapers, did not express need of additional information about COVID-19 vaccine, believed that COVID-19 vaccine is safe, were involved in working activities in the prison, and had a high school or university degree. CONCLUSIONS: These findings showed a high self-reported COVID-19 vaccination coverage in detained subjects, supporting the effectiveness of the strategy aimed at giving priority to COVID-19 vaccinations in prisons. Further efforts are needed to contrast the hesitancy of those who refused vaccination to increase their confidence about usefulness and safety of COVID-19 vaccines.

4.
Mar Environ Res ; 169: 105342, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33933902

RESUMO

In coastal marine ecosystems coralline algae often create biogenic reefs. These calcareous algal reefs affect their associated invertebrate communities via diurnal oscillations in photosynthesis, respiration and calcification processes. Little is known about how these biogenic reefs function and how they will be affected by climate change. We investigated the winter response of a Mediterranean intertidal biogenic reef, Ellissolandia elongata exposed in the laboratory to reduced pH conditions (i.e. ambient pH - 0.3, RCP 8.5) together with an extreme heatwave event (+1.4 °C for 15 days). Response variables considered both the algal physiology (calcification and photosynthetic rates) and community structure of the associated invertebrates (at taxonomic and functional level). The combination of a reduced pH with a heatwave event caused Ellisolandia elongata to significantly increase photosynthetic activity. The high variability of calcification that occurred during simulated night time conditions, indicates that there is not a simple, linear relationship between these two and may indicate that it will be resilient to future conditions of climate change. In contrast, the associated fauna were particularly negatively affected by the heatwave event, which impoverished the communities as opportunistic taxa became dominant. Local increases in oxygen and pH driven by the algae can buffer the microhabitat in the algal fronds, thus favouring the survival of small invertebrates.


Assuntos
Ecossistema , Rodófitas , Animais , Mudança Climática , Recifes de Corais , Concentração de Íons de Hidrogênio , Invertebrados , Água do Mar
5.
Eur J Pharm Sci ; 156: 105588, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33045367

RESUMO

The aim of this study was to optimize the parameters of the complex melt-emulsification process coupled with the spray-drying, in order to maintain the balance between solid lipid microparticles (SLMs) powders aerodynamic performance and salbutamol sulfate release rate. Quality target product profile was identified and risk management and principal component analysis were used to guide formulation development. Obtained dry powders for inhalation (DPIs) were evaluated in terms of SLMs size distribution, morphology, true density, drug content, solid state characterization studies, in vitro aerosol performance and in vitro drug release. SLMs micrographs indicated spherical, porous particles. Selected powders showed satisfactory aerosol performance with a mean mass aerodynamic diameter of around 3 µm and acceptable fine particle fraction (FPF). Addition of trehalose positively affected SLMs aerodynamic properties. The results of in vitro dissolution testing indicated that salbutamol sulfate release from the tested SLMs formulations was modified, in comparison to the raw drug release. In conclusion, SLMs in a form of DPIs were successfully developed and numerous factors that affects SLMs properties were identified in this study. Further research is required for full understanding of each factor's influence on SLMs properties and optimization of DPIs with maximized FPFs.


Assuntos
Sistemas de Liberação de Medicamentos , Inaladores de Pó Seco , Administração por Inalação , Aerossóis , Portadores de Fármacos , Composição de Medicamentos , Lipídeos , Tamanho da Partícula , Pós
6.
Zookeys ; (812): 1-22, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30647522

RESUMO

This study provides taxonomic and distributional data of bryozoan species from the Ross Sea area, mainly around Terra Nova Bay, based on specimens curated at the Italian National Antarctic Museum (MNA, Section of Genoa). Bryozoan specimens were collected at 75 different sampling stations in the Ross Sea and in the Magellan Strait, in a bathymetric range of 18-711 meters, during 13 expeditions of the Italian National Antarctic Research Program (PNRA) conducted between 1988 and 2014. A total of 282 MNA vouchers corresponding to 311 specimens and 127 morphospecies have been identified and included in the present dataset. 62% of the species were already reported for the Terra Nova Bay area, where most of the Italian samples come from, with a 35% of samples representing new records classified at the specific level, and 3% classified at the genus level. These new additions increase to 124 the total number of species known to occur in Terra Nova Bay. Four 3D-models of Antarctic bryozoans from the Ross Sea are also presented and will be released for research and educational purposes on the Museum website.

7.
Oncotarget ; 9(88): 35813-35829, 2018 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-30533197

RESUMO

Strigolactones (SLs) are carotenoid-derived plant hormones that exhibit anti-cancer activities. We previously demonstrated that two SL analogues, MEB55 and ST362, inhibit the growth and survival of various cancer cell lines. However, these compounds have low aqueous solubility and stability at physiological pH. Here, we generated SL-loaded glutathione/pH-responsive nanosponges (GSH/pH-NS) to selectively deliver SLs to prostate cancer cells and enhance their therapeutic efficacy. The SLs were readily incorporated into the GSH/pH-NS. The drug loading efficiency was 13.9% for MEB55 and 15.4% for ST362, and the encapsulation efficiency was 88.7% and 96.5%, respectively. Kinetic analysis revealed that release of MEB55 and ST362 from the GSH/pH-NS was accelerated at acidic pH and in the presence of a high GSH concentration. Evaluation of the effects of MEB55- and ST362-loaded GSH/pH-NS on the growth of DU145 (high GSH) and PC-3 (low GSH) prostate cancer cells revealed that the GSH/pH-NS inhibited the proliferation of DU145 cells to a greater extent than free MEB55 or ST362 over a range of concentrations. These findings indicate GSH/pH-NS are efficient tools for controlled delivery of SLs to prostate cancer cells and may enhance the therapeutic efficacy of these compounds.

8.
Chemistry ; 24(58): 15622-15630, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-29999556

RESUMO

A small library of carborane-BODIPY/aza-BODIPY dyads were efficiently synthesized by means of a novel convergent synthetic approach, the key step of which is a Pd-catalyzed Heck coupling reaction. The structural characterization and photoluminescence properties of the newly synthesized dyads were evaluated. The presence of the carborane did not significantly alter the photophysical patterns of the BODIPY or aza-BODIPY in the final fluorophores, but it produced a decrease of the emission fluorescent quantum yields that was in the range from 1.4 % for aza-BODIPY to 48 % for BODIPY-dyads. The carborane-BODIPY dyads were successfully incorporated into cells, especially compounds 2, 4 and 13, demonstrating their cytoplasmic localization. The fluorescent and biocompatibility properties make these compounds good candidates for in vitro cell tracking.

9.
J Exp Bot ; 69(9): 2333-2343, 2018 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-29554337

RESUMO

Strigolactones (SLs) are plant hormones with various functions in development, responses to stress, and interactions with (micro)organisms in the rhizosphere, including with seeds of parasitic plants. Their perception for hormonal functions requires an α,ß-hydrolase belonging to the D14 clade in higher plants; perception of host-produced SLs by parasitic seeds relies on similar but phylogenetically distinct proteins (D14-like). D14 and D14-like proteins are peculiar receptors, because they cleave SLs before undergoing a conformational change that elicits downstream events. Structure-activity relationship data show that the butenolide D-ring is crucial for bioactivity. We applied a bioisosteric approach to the structure of SLs by synthetizing analogues and mimics of natural SLs in which the D-ring was changed from a butenolide to a lactam and then evaluating their bioactivity. This was done by using a novel bioassay based on Arabidopsis transgenic lines expressing AtD14 fused to firefly luciferase, in parallel with the quantification of germination-inducing activity on parasitic seeds. The results obtained showed that the in planta bioassay is robust and quantitative, and thus can be confidently added to the SL-survey toolbox. The results also showed that modification of the butenolide ring into a lactam one significantly hampers the biological activity exhibited by SLs possessing a canonical lactonic D-ring.


Assuntos
Lactonas/química , Lactonas/metabolismo , Orobanche/química , Orobanche/metabolismo , Bioensaio/métodos , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/metabolismo , Relação Estrutura-Atividade
10.
Org Biomol Chem ; 15(38): 8232, 2017 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-28932861

RESUMO

Correction for 'Recent advances in the synthesis of analogues of phytohormones strigolactones with ring-closing metathesis as a key step' by Chiara Lombardi, et al., Org. Biomol. Chem., 2017, DOI: 10.1039/c7ob01917c.

11.
Org Biomol Chem ; 15(38): 8218-8231, 2017 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-28880031

RESUMO

In this paper, we synthesized and evaluated the biological activity of structural analogues of natural strigolactones in which the butenolide D-ring has been replaced with a γ-lactam. The key step to obtain the α,ß-unsaturated-γ-lactam was an RCM on suitably substituted amides. Strigolactones (SLs) are plant hormones with various developmental functions. As soil signaling chemicals, they are required for establishing beneficial mycorrhizal plant/fungus symbiosis. Beside these auxinic roles, recently SLs have been successfully investigated as antitumoral agents. Peculiar to the SL perception system is the enzymatic activity of the hormone receptor. SARs data have shown that the presence of the butenolide D-ring is crucial to retain the biological activity. The substitution of the butenolide with a lactam might shed light on the mechanism of perception. In the following, a dedicated in silico study suggested the binding modes of the synthesized compounds to the receptor of SLs in plants.


Assuntos
Lactonas/síntese química , Reguladores de Crescimento de Plantas/síntese química , Germinação/efeitos dos fármacos , Lactonas/química , Modelos Moleculares , Estrutura Molecular , Micorrizas , Orobanchaceae/efeitos dos fármacos , Reguladores de Crescimento de Plantas/química , Sementes/efeitos dos fármacos
12.
Mar Environ Res ; 125: 110-117, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28208067

RESUMO

Many aquatic animals grow into colonies of repeated, genetically identical, modules (zooids). Zooid interconnections enable colonies to behave as integrated functional units, while plastic responses to environmental changes may affect individual zooids. Plasticity includes the variable partitioning of resources to sexual reproduction, colony growth and maintenance. Maintenance often involves regeneration, which is also a routine part of the life history in some organisms, such as bryozoans. Here we investigate changes in regenerative capacity in the encrusting bryozoan Cryptosula pallasiana when cultured at different seawater pCO2 levels. The proportion of active zooids showing polypide regeneration was highest at current oceanic pH (8.1), but decreased progressively as pH declined below that value, reaching a six-fold reduction at pH 7.0. The zone of budding of new zooids at the colony periphery declined in size below pH 7.7. Under elevated pCO2 conditions, already experienced sporadically in coastal areas, skeletal corrosion was accompanied by the proportional reallocation of resources from polypide regeneration in old zooids to the budding of new zooids at the edge of the colony. Thus, future ocean acidification can affect colonial organisms by changing how they allocate resources, with potentially profound impacts on life-history patterns and ecological interactions.


Assuntos
Briozoários/fisiologia , Concentração de Íons de Hidrogênio , Água do Mar/química , Estresse Fisiológico , Animais , Monitoramento Ambiental , Invertebrados , Estágios do Ciclo de Vida
13.
Org Biomol Chem ; 15(4): 884-893, 2017 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-28045179

RESUMO

As part of our ongoing work on the synthesis of a new class of plant hormones named Strigolactones (SLs) and their analogues, we became interested in tracing bioactive molecules with red emitting BODIPY fluorophores in order to unravel signaling and distribution of SLs in plants. In this paper we report on an unprecedented Heck functionalization of azadipyrromethenes (aza-DIPY) which allows for the introduction of suitable functional groups to convert aza-BODIPY in bioconjugate complexes useful for untangling biological processes.


Assuntos
Compostos Aza/farmacocinética , Compostos de Boro/farmacocinética , Corantes Fluorescentes/farmacocinética , Arabidopsis/química , Compostos Aza/química , Compostos de Boro/química , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Estrutura Molecular , Processos Fotoquímicos , Raízes de Plantas/química , Espectroscopia de Luz Próxima ao Infravermelho , Distribuição Tecidual
14.
Evol Appl ; 9(9): 1054-1071, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27695515

RESUMO

Ocean acidification (OA) is likely to exert selective pressure on natural populations. Our ability to predict which marine species will adapt to OA and what underlies this adaptive potential is of high conservation and resource management priority. Using a naturally low-pH vent site in the Mediterranean Sea (Castello Aragonese, Ischia) mirroring projected future OA conditions, we carried out a reciprocal transplant experiment to investigate the relative importance of phenotypic plasticity and local adaptation in two populations of the sessile, calcifying polychaete Simplaria sp. (Annelida, Serpulidae, Spirorbinae): one residing in low pH and the other from a nearby ambient (i.e. high) pH site. We measured a suite of fitness-related traits (i.e. survival, reproductive output, maturation, population growth) and tube growth rates in laboratory-bred F2 generation individuals from both populations reciprocally transplanted back into both ambient and low-pH in situ habitats. Both populations showed lower expression in all traits, but increased tube growth rates, when exposed to low-pH compared with high-pH conditions, regardless of their site of origin suggesting that local adaptation to low-pH conditions has not occurred. We also found comparable levels of plasticity in the two populations investigated, suggesting no influence of long-term exposure to low pH on the ability of populations to adjust their phenotype. Despite high variation in trait values among sites and the relatively extreme conditions at the low pH site (pH < 7.36), response trends were consistent across traits. Hence, our data suggest that, for Simplaria and possibly other calcifiers, neither local adaptations nor sufficient phenotypic plasticity levels appear to suffice in order to compensate for the negative impacts of OA on long-term survival. Our work also emphasizes the utility of field experiments in natural environments subjected to high level of pCO 2 for elucidating the potential for adaptation to future scenarios of OA.

15.
J Nat Prod ; 78(11): 2624-33, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26502774

RESUMO

Strigolactones (SLs) are new plant hormones with various developmental functions. They are also soil signaling chemicals that are required for establishing beneficial mycorrhizal plant/fungus symbiosis. In addition, SLs play an essential role in inducing seed germination in root-parasitic weeds, which are one of the seven most serious biological threats to food security. There are around 20 natural SLs that are produced by plants in very low quantities. Therefore, most of the knowledge on SL signal transduction and associated molecular events is based on the application of synthetic analogues. Stereochemistry plays a crucial role in the structure-activity relationship of SLs, as compounds with an unnatural D-ring configuration may induce biological effects that are unrelated to SLs. We have synthesized a series of strigolactone analogues, whose absolute configuration has been elucidated and related with their biological activity, thus confirming the high specificity of the response. Analogues bearing the R-configured butenolide moiety showed enhanced biological activity, which highlights the importance of this stereochemical motif.


Assuntos
Lactonas/farmacologia , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/farmacologia , Germinação/efeitos dos fármacos , Lactonas/química , Estrutura Molecular , Raízes de Plantas/química , Plantas Daninhas/efeitos dos fármacos , Sementes/efeitos dos fármacos , Relação Estrutura-Atividade , Simbiose
16.
Sci Rep ; 5: 12009, 2015 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-26156262

RESUMO

Anthropogenic atmospheric carbon dioxide (CO2) is being absorbed by seawater resulting in increasingly acidic oceans, a process known as ocean acidification (OA). OA is thought to have largely deleterious effects on marine invertebrates, primarily impacting early life stages and consequently, their recruitment and species' survival. Most research in this field has been limited to short-term, single-species and single-life stage studies, making it difficult to determine which taxa will be evolutionarily successful under OA conditions. We circumvent these limitations by relating the dominance and distribution of the known polychaete worm species living in a naturally acidic seawater vent system to their life history strategies. These data are coupled with breeding experiments, showing all dominant species in this natural system exhibit parental care. Our results provide evidence supporting the idea that long-term survival of marine species in acidic conditions is related to life history strategies where eggs are kept in protected maternal environments (brooders) or where larvae have no free swimming phases (direct developers). Our findings are the first to formally validate the hypothesis that species with life history strategies linked to parental care are more protected in an acidifying ocean compared to their relatives employing broadcast spawning and pelagic larval development.


Assuntos
Organismos Aquáticos , Comportamento Animal , Concentração de Íons de Hidrogênio , Invertebrados , Água do Mar/química , Animais , Organismos Aquáticos/classificação , Organismos Aquáticos/genética , Clima , Invertebrados/classificação , Invertebrados/genética
17.
R Soc Open Sci ; 2(2): 140413, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26064601

RESUMO

Understanding is currently limited of the biological processes underlying the responses of modular organisms to climate change and the potential to adapt through morphological plasticity related to their modularity. Here, we investigate the effects of ocean acidification and seawater warming on the growth, life history and morphological plasticity in the modular bryozoan Calpensia nobilis using transplantation experiments in a shallow Mediterranean volcanic CO2 vents system that simulates pH values expected for the year 2100. Colonies exposed at vent sites grew at approximately half the rate of those from the control site. Between days 34 and 48 of the experiment, they reached a possible 'threshold', due to the combined effects of exposure time and pH. Temperature did not affect zooid length, but longer zooids with wider primary orifices occurred in low pH conditions close to the vents. Growth models describing colony development under different environmental scenarios suggest that stressed colonies of C. nobilis reallocate metabolic energy to the consolidation and strengthening of existing zooids. This is interpreted as a change in life-history strategy to support persistence under unfavourable environmental conditions. Changes in the skeletal morphology of zooids evident in C. nobilis during short-time (87 days) exposure experiments reveal morphological plasticity that may indicate a potential to adapt to the more acidic Mediterranean predicted for the future.

18.
Mar Environ Res ; 112(Pt B): 11-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26004519

RESUMO

Coralline algae are calcareous algae able to build biogenic structures, thus playing a key-role as marine biodiversity promoters and calcium carbonate producers. The aim was to estimate the growth of Ellisolandia elongata under thermal stress. E. elongata were cultured for 2, 4 and 6 months under "natural" temperature (Tc) and increased temperature (Ti = Tc + 3 °C). In order to determine a possible culturing effect, growth in the field was also measured. For the first time, Alizarin Red S dye was used in high energy shallow water environments. Thallus linear extension was higher in the cultured specimens (Tc and Ti) compared to the field specimens. The carbonate mass in the field was higher than in Ti and Tc after 2, 4 months but decreased after 6 months. Partly unknown in situ environmental factors could have affected growth and calcification rates in the field while thermal adaptation could explain growth rates in the culturing experiment.


Assuntos
Aquecimento Global , Temperatura Alta , Rodófitas/crescimento & desenvolvimento , Estresse Fisiológico , Calcificação Fisiológica , Carbonato de Cálcio/metabolismo , Itália , Mar Mediterrâneo , Água do Mar/química
19.
Biol Rev Camb Philos Soc ; 90(4): 1118-50, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25370313

RESUMO

Many animal phyla have the physiological ability to produce biomineralized skeletons with functional roles that have been shaped by natural selection for more than 500 million years. Among these are bryozoans, a moderately diverse phylum of aquatic invertebrates with a rich fossil record and importance today as bioconstructors in some shallow-water marine habitats. Biomineralizational patterns and, especially, processes are poorly understood in bryozoans but are conventionally believed to be similar to those of the related lophotrochozoan phyla Brachiopoda and Mollusca. However, bryozoan skeletons are more intricate than those of these two phyla. Calcareous skeletons have been acquired independently in two bryozoan clades - Stenolaemata in the Ordovician and Cheilostomata in the Jurassic - providing an evolutionary replicate. This review aims to highlight the importance of biomineralization in bryozoans and focuses on their skeletal ultrastructures, mineralogy and chemistry, the roles of organic components, the evolutionary history of bimineralization in bryozoans with respect to changes in seawater chemistry, and the impact of contemporary global changes, especially ocean acidification, on bryozoan skeletons. Bryozoan skeletons are constructed from three different wall types (exterior, interior and compound) differing in the presence/absence and location of organic cuticular layers. Skeletal ultrastructures can be classified into wall-parallel (i.e. laminated) and wall-perpendicular (i.e. prismatic) fabrics, the latter apparently found in only one of the two biomineralizing clades (Cheilostomata), which is also the only clade to biomineralize aragonite. A plethora of ultrastructural fabrics can be recognized and most occur in combination with other fabrics to constitute a fabric suite. The proportion of aragonitic and bimineralic bryozoans, as well as the Mg content of bryozoan skeletons, show a latitudinal increase into the warmer waters of the tropics. Responses of bryozoan mineralogy and skeletal thickness to oscillations between calcite and aragonite seas through geological time are equivocal. Field and laboratory studies of living bryozoans have shown that predicted future changes in pH (ocean acidification) combined with global warming are likely to have detrimental effects on calcification, growth rate and production of polymorphic zooids for defence and reproduction, although some species exhibit reasonable levels of resilience. Some key questions about bryozoan biomineralization that need to be addressed are identified.


Assuntos
Briozoários/fisiologia , Minerais/metabolismo , Distribuição Animal , Animais , Fenômenos Biomecânicos , Briozoários/ultraestrutura , Fósseis
20.
Philos Trans R Soc Lond B Biol Sci ; 368(1627): 20120444, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23980245

RESUMO

Metabolic rate determines the physiological and life-history performances of ectotherms. Thus, the extent to which such rates are sensitive and plastic to environmental perturbation is central to an organism's ability to function in a changing environment. Little is known of long-term metabolic plasticity and potential for metabolic adaptation in marine ectotherms exposed to elevated pCO2. Consequently, we carried out a series of in situ transplant experiments using a number of tolerant and sensitive polychaete species living around a natural CO2 vent system. Here, we show that a marine metazoan (i.e. Platynereis dumerilii) was able to adapt to chronic and elevated levels of pCO2. The vent population of P. dumerilii was physiologically and genetically different from nearby populations that experience low pCO2, as well as smaller in body size. By contrast, different populations of Amphiglena mediterranea showed marked physiological plasticity indicating that adaptation or acclimatization are both viable strategies for the successful colonization of elevated pCO2 environments. In addition, sensitive species showed either a reduced or increased metabolism when exposed acutely to elevated pCO2. Our findings may help explain, from a metabolic perspective, the occurrence of past mass extinction, as well as shed light on alternative pathways of resilience in species facing ongoing ocean acidification.


Assuntos
Aclimatação/fisiologia , Adaptação Biológica/fisiologia , Dióxido de Carbono/análise , Meio Ambiente , Poliquetos/fisiologia , Água do Mar/química , Animais , Concentração de Íons de Hidrogênio , Modelos Lineares , Mar Mediterrâneo , Poliquetos/metabolismo , Especificidade da Espécie
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