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1.
Animals (Basel) ; 13(11)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37889740

RESUMO

Traditional methods for age determination of wildlife include either slicing thin sections off or grinding a tooth, both of which are laborious and invasive. Especially when it comes to ancient and valuable museum samples of rare or extinct species, non-invasive methods are preferable. In this study, X-ray micro-computed tomography (µ-CT) was verified as an alternative non-invasive method for age determination of three species within the order of Carnivora and suborders Odontoceti. Teeth from 13 red foxes (Vulpes vulpes), 2 American mink (Neogale vison), and 2 harbor porpoises (Phocoena phocoena) of known age were studied using µ-CT. The number of visible dental growth layers in the µ-CT were highly correlated with true age for all three species (R2 = 96%, p < 0.001). In addition, the Bland-Altman plot showed high agreement between the age of individuals and visible dental layers represented in 2D slices of the 3D µ-CT images. The true age of individuals was on average 0.3 (±0.6 SD) years higher than the age interpreted by the µ-CT image, and there was a 95% agreement between the true age and the age interpreted from visible dental layers in the µ-CT.

2.
bioRxiv ; 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37292721

RESUMO

The majority of the world population carry the gastric pathogen Helicobacter pylori. Fortunately, most individuals experience only low-grade or no symptoms, but in many cases the chronic inflammatory infection develops into severe gastric disease, including duodenal ulcer disease and gastric cancer. Here we report on a protective mechanism where H. pylori attachment and accompanying chronic mucosal inflammation can be reduced by antibodies that are present in a vast majority of H. pylori carriers. These antibodies block binding of the H. pylori attachment protein BabA by mimicking BabA's binding to the ABO blood group glycans in the gastric mucosa. However, many individuals demonstrate low titers of BabA blocking antibodies, which is associated with an increased risk for duodenal ulceration, suggesting a role for these antibodies in preventing gastric disease.

3.
R Soc Open Sci ; 9(12): 220459, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36533195

RESUMO

Recently, a unique mechanism for protecting the airway during lunge feeding was discovered in rorqual whales (Balaenopteridae). This mechanism is based on an oral plug structure in the soft palate with similarities in musculo-fatty composition to the nasal plugs protecting the respiratory tract of rorquals from water entry and barotrauma during diving. As a follow-up, we present here a developmental series on fetal, prenatal, juvenile and adult specimens across five species of rorquals, showing differential maturation of the nasal and oral respiratory protection plugs. Nasal plugs are fully formed to serve an immediate crucial function at birth. By contrast, the soft palate remains muscular until the onset of solid food intake, where a musculo-fatty oral plug is developed.

4.
Nat Commun ; 13(1): 6400, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36302850

RESUMO

Shared cars will likely have larger annual vehicle driving distances than individually owned cars. This may accelerate passenger car retirement. Here we develop a semi-empirical lifetime-driving intensity model using statistics on Swedish vehicle retirement. This semi-empirical model is integrated with a carbon footprint model, which considers future decarbonization pathways. In this work, we show that the carbon footprint depends on the cumulative driving distance, which depends on both driving intensity and calendar aging. Higher driving intensities generally result in lower carbon footprints due to increased cumulative driving distance over the vehicle's lifetime. Shared cars could decrease the carbon footprint by about 41% in 2050, if one shared vehicle replaces ten individually owned vehicles. However, potential empty travel by autonomous shared vehicles-the additional distance traveled to pick up passengers-may cause carbon footprints to increase. Hence, vehicle durability and empty travel should be considered when designing low-carbon car sharing systems.

5.
Int J Emerg Med ; 15(1): 47, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096726

RESUMO

BACKGROUND: Most Swedish emergency departments (ED) use the triage system Rapid Emergency Triage and Treatment System (RETTS©), which over time has proven to prioritize patients to higher triage levels. When many patients are prioritized to high triage levels, challenges with identifying true high-risk patients and increased waiting time for these patients has emerged. In order to achieve a more balanced triage in relation to actual medical risk, the triage system WEst coast System for Triage (WEST) was developed, based on the South African Triage Scale (SATS). The aim of this study was to perform an initial evaluation of the novel emergency triage system WEST compared to the existing RETTS©. METHODS: Both RETTS© and WEST are five level triage systems illustrated by colors. Nurses from each of the three adult EDs of Sahlgrenska University Hospital in Gothenburg and the ambulance service assessed and triaged 1510 patients according to RETTS© and immediately thereafter filled out the WEST triage form. Data from each triage report were analyzed and grouped according to the triage color, chief complaint, and outcome of each patient. Data on discharge categories and events within 72 h were also collected. Data were analyzed with descriptive statistical methods. RESULTS: In general, WEST displayed lower levels of prioritization compared to RETTS©, with no observed impact on patients' medical outcomes. In RETTS© orange triage level, approximately 50% of the patients were down prioritized in WEST to yellow or green triage levels. Also, in the RETTS© yellow triage level, more than 55% were down prioritized to green triage level in WEST. The number of patients who experienced a serious event during the first 72 h was few. Three patients died, these were all prioritized to red triage level in RETTS©. In WEST two of these patients were prioritized to red triage level and one to orange triage level. All these patients were admitted to hospital before deterioration. CONCLUSIONS: WEST may reduce over prioritization at the ED, especially in the orange and yellow triage levels of RETTS©, with no observed increase in medical risk. WEST can be recommended for a clinical comparative study.

6.
Environ Sci Technol ; 56(13): 9593-9603, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35735988

RESUMO

This research investigates carbon footprint impacts for full fleet electrification of Swedish passenger car travel in combination with different charging conditions, including electric road system (ERS) that enables dynamic on-road charging. The research applies a prospective life cycle analysis framework for estimating carbon footprints of vehicles, fuels, and infrastructure. The framework includes vehicle stock turnover modeling of fleet electrification and modeling of optimal battery capacity for different charging conditions based on Swedish real-world driving patterns. All new car sales are assumed to be electric after 2030 following phase-out policies for gasoline and diesel cars. Implementing ERS on selected high-traffic roads could yield significant avoided emissions in battery manufacturing compared to the additional emissions in ERS construction. ERS combined with stationary charging could enable additional reductions in the cumulative carbon footprint of about 12-24 million tons of CO2 over 30 years (2030-2060) compared to an electrified fleet only relying on stationary charging. The range depends on uncertainty in emission abatement in global manufacturing, where the lower is based on Paris Agreement compliance and the higher on current climate policies. A large share of the reduction could be achieved even if only a small share of the cars adopts the optimized battery capacities.


Assuntos
Automóveis , Emissões de Veículos , Gasolina , Veículos Automotores , Estudos Prospectivos , Emissões de Veículos/análise , Emissões de Veículos/prevenção & controle
7.
Clim Change ; 172(1-2): 1, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35529022

RESUMO

It has been claimed that COVID-19 public stimulus packages could be sufficient to meet the short-term energy investment needs to leverage a shift toward a pathway consistent with the 1.5 °C target of the Paris Agreement. Here, we provide complementary perspectives to reiterate that substantial, broad, and sustained policy efforts beyond stimulus packages will be needed for achieving the Paris Agreement long-term targets. Low-carbon investments will need to scale up and persist over the next several decades following short-term stimulus packages. The required total energy investments in the real world can be larger than the currently available estimates from integrated assessment models (IAMs). Existing databases from IAMs are not sufficient for analyzing the effect of public spending on emission reduction. To inform what role COVID-19 stimulus packages and public investments may play for reaching the Paris Agreement targets, explicit modelling of such policies is required.

9.
Nutr Rev ; 80(6): 1648-1663, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-34741520

RESUMO

Cereal grains are the main dietary source of energy, carbohydrates, and plant proteins world-wide. Currently, only 41% of grains are used for human consumption, and up to 35% are used for animal feed. Cereals have been overlooked as a source of environmentally sustainable and healthy plant proteins and could play a major role in transitioning towards a more sustainable food system for healthy diets. Cereal plant proteins are of good nutritional quality, but lysine is often the limiting amino acid. When consumed as whole grains, cereals provide health-protecting components such as dietary fiber and phytochemicals. Shifting grain use from feed to traditional foods and conceptually new foods and ingredients could improve protein security and alleviate climate change. Rapid development of new grain-based food ingredients and use of grains in new food contexts, such as dairy replacements and meat analogues, could accelerate the transition. This review discusses recent developments and outlines future perspectives for cereal grain use.


Assuntos
Fibras na Dieta , Grão Comestível , Fibras na Dieta/análise , Grão Comestível/química , Humanos , Valor Nutritivo , Proteínas de Plantas , Grãos Integrais
10.
Sci Adv ; 7(22)2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34049873

RESUMO

Greenhouse gas (GHG) metrics, that is, conversion factors to evaluate the emissions of non-CO2 GHGs on a common scale with CO2, serve crucial functions in the implementation of the Paris Agreement. While different metrics have been proposed, their economic cost-effectiveness has not been investigated under a range of pathways, including those substantially overshooting the temperature targets. Here, we show that cost-effective metrics for methane that minimize the overall mitigation costs are time-dependent, primarily determined by the pathway, and strongly influenced by temperature overshoot. Parties to the Paris Agreement have already adopted the conventional GWP100 (100-year global warming potential), which is shown to be a good approximation of cost-effective metrics for the coming decades. In the longer term, however, we suggest that parties consider adapting the choice of common metrics to the future pathway as it unfolds, as part of the recurring global stocktake, if global cost-effectiveness is a key consideration.

11.
ESC Heart Fail ; 7(6): 3633-3643, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32881399

RESUMO

AIMS: The aim of this study is to study the introduction of sacubitril/valsartan (sac/val) in Sweden with regards to regional differences, clinical characteristics, titration patterns, and determinants of use and discontinuation. METHODS AND RESULTS: A national cohort of heart failure was defined from the Swedish Prescribed Drug Register and National Patient Register. A subcohort with additional data from the Swedish Heart Failure Registry (SwedeHF) was also studied. Cohorts were subdivided as per sac/val prescription and registration in SwedeHF. Median sac/val prescription rate was 20 per 100 000 inhabitants. Between April 2016 and December 2017, we identified 2037 patients with ≥1 sac/val prescription, of which 1144 (56%) were registered in SwedeHF. Overall, patients prescribed with sac/val were younger, more frequently male, and had less prior cardiovascular disease than non-sac/val patients. In SwedeHF subcohort, patients prescribed with sac/val had lower ejection fraction. Overall, younger age [hazard ratio 2.81 (95% confidence interval 2.45-3.22)], registration in SwedeHF [1.97 (1.83-2.12)], male gender [1.50 (1.37-1.64)], ischaemic heart disease [1.50 (1.39-1.62)], lower left ventricular ejection fraction [3.06 (2.18-4.31)], and New York Heart Association IV [1.50 (1.22-1.84)] were predictors for sac/val use. As initiation dose in the sac/val cohort, 38% received 24/26 mg, 54% 49/51 mg, and 9% 97/103 mg. Up-titration to the target dose was achieved in 57% of the overall cohort over a median follow-up of 6 months. The estimated treatment persistence for any dose at 360 days was 82%. CONCLUSIONS: Implementation of sac/val in Sweden was slow and varied five-fold across different regions; younger age, male, SwedeHF registration, and ischaemic heart disease were among the independent predictors of receiving sac/val. Overall, treatment persistence and tolerability was high.

12.
Sci Rep ; 9(1): 8939, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31222107

RESUMO

In situ fibrillation of plant proteins in presence of the superparamagnetic iron oxide nanoparticles (NP) promoted formation of a hybrid nanocomposite. The morphology of NP-fibril composite was revealed using ex-situ atomic force microscopy (AFM) in air. The NP-fibrils were associated into extended multi-fibril structures, indicating that the addition of NPs promoted protein association via ß-sheet assembly. Real-time movement of NPs attached to fibrils under an external magnetic field was visualized using in-situ AFM in liquid, revealing that composite structures were stable at low pH, and displaying dipolar property of the NPs in the composite at high pH. Changes in magnetic properties of NPs when interacting with protein fibrils were quantitatively mapped using magnetic force microscopy (MFM). The magnetic moment of the NPs in composite was increased by co-existing with protein at low pH, while their dipolar nature was maintained at high pH. Self-assembly of the protein into fibrils is accelerated with increasing NP concentration within an optimal range, which is attributed to a fibrillation-competent conformation of the peptides. The latter was explained by the formation of favorable hydrogen bonds, electrostatic interactions, and efficient surface energy transfer between NPs and proteins.


Assuntos
Magnetismo , Nanopartículas de Magnetita/química , Proteínas de Plantas/química , Eletroforese em Gel de Poliacrilamida , Microscopia de Força Atômica , Ligação Proteica , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Nutrients ; 10(11)2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30380770

RESUMO

Sourdough fermented bread has been suggested to have beneficial health effects, in part mediated by increased satiety in the postprandial phase, but only limited research has been conducted to verify this. The current study aimed to investigate the effect of the amounts of sourdough and rye in soft bread on postprandial appetite. On 6 occasions, 23 healthy volunteers consumed 5 different test breads, with varying amount of rye and sourdough, and a yeast-fermented refined wheat control bread as part of a breakfast meal. The sourdough ranged between 9⁻51% of dough weight and rye content between 35⁻48% of flour weight. Appetite was recorded using visual analogue scales from immediately before breakfast and every 30 min the following 4 h. An ad libitum lunch was served 4 h after the breakfast meal, from which voluntary energy intake was measured. While some of the test breads resulted in lower hunger ratings and increased sense of fullness compared to the refined wheat bread, there were no differences between the test breads. The content of rye in the test breads differed within a narrow range, which might explain the lack of a consistent effect of rye on appetite. Microstructural examination of the test breads showed an increased aggregation of proteins in the breads with high content of sourdough, indicating additional changes to the breads, beyond change in pH, which may counteract the potential effect of decreased pH in the bread on appetite. In conclusion, our study does not support an effect of sourdough on appetite and ad libitum food intake.


Assuntos
Apetite , Pão/análise , Ingestão de Alimentos , Adulto , Idoso , Desjejum , Estudos Cross-Over , Ingestão de Energia , Feminino , Fermentação , Farinha/análise , Voluntários Saudáveis , Humanos , Fome/fisiologia , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial , Secale , Triticum , Adulto Jovem
14.
Front Immunol ; 9: 950, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29867939

RESUMO

T-cell activation is characteristic during the development of atherosclerosis. While overall T-cell responses have been implicated in disease acceleration, regulatory T cells (Tregs) exhibit atheroprotective effects. The expression of the enzyme indoleamine 2,3-dioxygenase-1 (IDO1), which catalyzes the degradation of tryptophan (Trp) along the kynurenine pathway, has been implicated in the induction and expansion of Treg populations. Hence, Tregs can reciprocally promote IDO1 expression in dendritic cells (DCs) via reverse signaling mechanisms during antigen presentation. In this study, we hypothesize that triggering the "Treg/IDO axis" in the artery wall is atheroprotective. We show that apolipoprotein B100-pulsed tumor growth factor beta 2-treated tolerogenic DCs promote de novo FoxP3+ Treg expansion in vivo. This local increase in Treg numbers is associated with increased vascular IDO1 expression and a robust reduction in the atherosclerotic burden. Using human primary cell cultures, we show for the first time that IDO1 expression and activity can be regulated by cytotoxic T-lymphocyte associated protein-4, which is a constitutive molecule expressed and secreted by Tregs, in smooth muscle cells, endothelial cells, and macrophages. Altogether, our data suggest that Tregs and IDO1-mediated Trp metabolism can mutually regulate one another in the vessel wall to promote vascular tolerance mechanisms that limit inflammation and atherosclerosis.


Assuntos
Aterosclerose/etiologia , Aterosclerose/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Ativação Linfocitária , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Vasculite/etiologia , Vasculite/metabolismo , Animais , Aterosclerose/patologia , Biomarcadores , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Ativação Enzimática , Expressão Gênica , Humanos , Hiperlipidemias/complicações , Hiperlipidemias/metabolismo , Imuno-Histoquímica , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Contagem de Linfócitos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Transgênicos , Fenótipo , Placa Aterosclerótica/etiologia , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Linfócitos T Reguladores/efeitos dos fármacos , Fator de Crescimento Transformador beta2/metabolismo , Fator de Crescimento Transformador beta2/farmacologia , Vasculite/patologia
15.
Arterioscler Thromb Vasc Biol ; 38(8): e145-e158, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29880490

RESUMO

Objective- Dyslipidemia is a component of the metabolic syndrome, an established risk factor for atherosclerotic cardiovascular disease, and is also observed in various autoimmune and chronic inflammatory conditions. However, there are limited opportunities to study the impact of acquired dyslipidemia on cardiovascular and immune pathology. Approach and Results- We designed a model system that allows for the conversion to a state of acute hyperlipidemia in adult life, so that the consequences of such a transition could be observed, through conditionally deleting APOE (apolipoprotein E) in the adult mouse. The transition to hypercholesterolemia was accompanied by adaptive immune responses, including the expansion of T lymphocyte helper cell 1, T follicular helper cell, and T regulatory subsets and the formation of germinal centers. Unlike steady-state Apoe-/- mice, abrupt loss of APOE induced rapid production of antibodies recognizing rheumatoid disease autoantigens. Genetic ablation of the germinal center reduced both autoimmunity and atherosclerosis, indicating that the immune response that follows loss of APOE is independent of atherosclerosis but nevertheless promotes plaque development. Conclusions- Our findings suggest that immune activation in response to hyperlipidemia could contribute to a wide range of inflammatory autoimmune diseases, including atherosclerosis.


Assuntos
Imunidade Adaptativa , Aorta/imunologia , Doenças da Aorta/imunologia , Apolipoproteínas E/imunologia , Aterosclerose/imunologia , Autoimunidade , Dislipidemias/imunologia , Inflamação/imunologia , Animais , Aorta/metabolismo , Aorta/patologia , Doenças da Aorta/genética , Doenças da Aorta/metabolismo , Doenças da Aorta/patologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Progressão da Doença , Dislipidemias/genética , Dislipidemias/metabolismo , Dislipidemias/patologia , Centro Germinativo/imunologia , Centro Germinativo/metabolismo , Imunidade Humoral , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Placa Aterosclerótica , Transdução de Sinais , Linfócitos T/imunologia , Linfócitos T/metabolismo , Fatores de Tempo
16.
Eur J Nutr ; 57(4): 1651-1666, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28417207

RESUMO

PURPOSE: Rye products have been reported to elicit postprandial insulin and glucose responses which may be beneficial for prevention of type-2 diabetes. However, mechanisms underlying variations in responses related to processing techniques are not fully understood. METHODS: Five differently processed rye products (sourdough-fermented bread, fermented and unfermented crispbread, extrusion-cooked rye, and porridge) and refined wheat bread were characterised. Two in vitro methods, a dynamic method simulating digestion in the stomach and small intestine and a static method, simulating conditions in the stomach were used to determine viscosity development, structural changes and release of glucose during digestion. RESULTS: Structural and compositional differences induced by processing influenced product digestion. Gastric disintegration and digesta particle size were related to characteristics of the starch/protein matrix, while digesta viscosity was reduced due to fibre degradation during fermentation. More cohesive boluses were associated with slower glucose release. Sourdough fermentation increased amylose leakage and appeared to inhibit starch hydrolysis despite low digesta viscosity and rapid disintegration. CONCLUSIONS: The net release of glucose during digestion of foods is determined by several factors which may vary in their importance depending on product specific properties.


Assuntos
Digestão/fisiologia , Manipulação de Alimentos , Secale/metabolismo , Triticum/metabolismo , Glicemia , Pão , Fibras na Dieta , Período Pós-Prandial , Amido
17.
Br J Nutr ; 118(9): 686-697, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29185930

RESUMO

Sourdough fermentation is considered to have beneficial effects on postprandial satiety and metabolic responses, but studies demonstrating effects at physiological conditions are lacking. The aim of this acute breakfast intervention study was to determine the effect of consumption of sourdough-fermented and unfermented rye crispbread on self-rated appetite, postprandial glucose and insulin response in healthy subjects. In all, twenty-four Swedish adults were included in a single-blinded, randomised cross-over trial. Three crispbreads (sourdough-fermented and unfermented whole grain rye and yeast-fermented refined wheat as control) were consumed as part of a standardised breakfast. Subjective appetite score, assessed using visual analogue scale, and plasma glucose and insulin concentrations were measured at baseline and postprandially until 360 and 240 min, respectively. Structural changes and viscosity during mastication and gastric digestion were investigated using in vitro methods. Hunger and desire to eat were lower (P<0·05) based on AUC measurements after intake of sourdough-fermented rye crispbread compared with after intake of yeast-fermented refined wheat crispbread. On the basis of AUC (0-230 min), insulin response was lowest after intake of unfermented rye crispbread compared with sourdough-fermented rye and yeast-fermented refined wheat crispbread. Degradation of viscous fibres and faster bolus disintegration for the sourdough-fermented bread may partly explain the less favourable metabolic responses compared with unfermented bread. Our results showed that food processing affects the composition and structural characteristics of rye bread, which has implications for appetite and metabolic responses.


Assuntos
Apetite , Glicemia/metabolismo , Pão , Alimentos Fermentados , Período Pós-Prandial , Secale/química , Adulto , Desjejum , Estudos Cross-Over , Fibras na Dieta/administração & dosagem , Digestão , Feminino , Peptídeo 1 Semelhante ao Glucagon/sangue , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Saciação , Método Simples-Cego , Suécia , Triticum/química , Grãos Integrais/química , Adulto Jovem
18.
BMC Ecol ; 17(1): 14, 2017 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-28381278

RESUMO

BACKGROUND: Establishing populations in ecologically marginal habitats may require substantial phenotypic changes that come about through phenotypic plasticity, local adaptation, or both. West-Eberhard's "plasticity-first" model suggests that plasticity allows for rapid colonisation of a new environment, followed by directional selection that develops local adaptation. Two predictions from this model are that (i) individuals of the original population have high enough plasticity to survive and reproduce in the marginal environment, and (ii) individuals of the marginal population show evidence of local adaptation. Individuals of the macroalga Fucus vesiculosus from the North Sea colonised the hyposaline (≥2-3‰) Baltic Sea less than 8000 years ago. The colonisation involved a switch from fully sexual to facultative asexual recruitment with release of adventitious branches that grow rhizoids and attach to the substratum. To test the predictions from the plasticity-first model we reciprocally transplanted F. vesiculosus from the original population (ambient salinity 24‰) and from the marginal population inside the Baltic Sea (ambient salinity 4‰). We also transplanted individuals of the Baltic endemic sister species F. radicans from 4 to 24‰. We assessed the degree of plasticity and local adaptation in growth and reproductive traits after 6 months by comparing the performance of individuals in 4 and 24‰. RESULTS: Branches of all individuals survived the 6 months period in both salinities, but grew better in their native salinity. Baltic Sea individuals more frequently developed asexual traits while North Sea individuals initiated formation of receptacles for sexual reproduction. CONCLUSIONS: Marine individuals of F. vesiculosus are highly plastic with respect to salinity and North Sea populations can survive the extreme hyposaline conditions of the Baltic Sea without selective mortality. Plasticity alone would thus allow for an initial establishment of this species inside the postglacial Baltic Sea at salinities where reproduction remains functional. Since establishment, the Baltic Sea populations have evolved adaptations to extreme hyposaline waters and have in addition evolved asexual recruitment that, however, tends to impede local adaptation. Overall, our results support the "plasticity-first" model for the initial colonisation of the Baltic Sea by Fucus vesiculosus.


Assuntos
Fucus/fisiologia , Água do Mar/química , Aclimatação , Ecossistema , Meio Ambiente , Fucus/crescimento & desenvolvimento , Salinidade
19.
PLoS One ; 11(8): e0161266, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27525655

RESUMO

Closely related taxa provide significant case studies for understanding evolution of new species but may simultaneously challenge species identification and definition. In the Baltic Sea, two dominant and perennial brown algae share a very recent ancestry. Fucus vesiculosus invaded this recently formed postglacial sea 8000 years ago and shortly thereafter Fucus radicans diverged from this lineage as an endemic species. In the Baltic Sea both species reproduce sexually but also recruit fully fertile new individuals by asexual fragmentation. Earlier studies have shown local differences in morphology and genetics between the two taxa in the northern and western Bothnian Sea, and around the island of Saaremaa in Estonia, but geographic patterns seem in conflict with a single origin of F. radicans. To investigate the relationship between northern and Estonian distributions, we analysed the genetic variation using 9 microsatellite loci in populations from eastern Bothnian Sea, Archipelago Sea and the Gulf of Finland. These populations are located in between earlier studied populations. However, instead of bridging the disparate genetic gap between N-W Bothnian Sea and Estonia, as expected from a simple isolation-by-distance model, the new populations substantially increased overall genetic diversity and showed to be strongly divergent from the two earlier analysed regions, showing signs of additional distinct populations. Contrasting earlier findings of increased asexual recruitment in low salinity in the Bothnian Sea, we found high levels of sexual reproduction in some of the Gulf of Finland populations that inhabit extremely low salinity. The new data generated in this study supports the earlier conclusion of two reproductively isolated but very closely related species. However, the new results also add considerable genetic and morphological complexity within species. This makes species separation at geographic scales more demanding and suggests a need for more comprehensive approaches to further disentangle the intriguing relationship and history of the Baltic Sea fucoids.


Assuntos
Fucus/genética , Variação Genética , Oceanos e Mares , Europa (Continente) , Fucus/classificação , Frequência do Gene , Genótipo , Repetições de Microssatélites/genética , Salinidade
20.
PLoS One ; 11(2): e0147791, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26840533

RESUMO

A protocol for extraction of yellow mealworm larvae proteins was established, conditions were evaluated and the resulting protein extract was characterised. The freeze-dried yellow mealworm larvae contained around 33% fat, 51% crude protein and 43% true protein on a dry matter basis. The true protein content of the protein extract was about 75%, with an extraction rate of 70% under optimised extraction conditions using 0.25 M NaOH, a NaOH solution:ethanol defatted worm ratio of 15:1 mL/g, 40°C for 1 h and extraction twice. The protein extract was a good source of essential amino acids. The lowest protein solubility in distilled water solution was found between pH 4 and 5, and increased with either increasing or decreasing pH. Lower solubility was observed in 0.5 M NaCl solution compared with distilled water. The rheological tests indicated that temperature, sample concentration, addition of salt and enzyme, incubation time and pH alterations influenced the elastic modulus of yellow mealworm protein extract (YMPE). These results demonstrate that the functional properties of YMPE can be modified for different food applications.


Assuntos
Proteínas Alimentares/química , Proteínas de Insetos/química , Tenebrio/química , Aminoácidos/análise , Aminoácidos/química , Animais , Proteínas Alimentares/análise , Ácidos Graxos/química , Concentração de Íons de Hidrogênio , Proteínas de Insetos/análise , Larva , Reologia , Solubilidade , Temperatura
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