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1.
Mol Ecol ; 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37697448

RESUMO

Phytoplankton have short generation times, flexible reproduction strategies, large population sizes and high standing genetic diversity, traits that should facilitate rapid evolution under directional selection. We quantified local adaptation of copper tolerance in a population of the diatom Skeletonema marinoi from a mining-exposed inlet in the Baltic Sea and in a non-exposed population 100 km away. We hypothesized that mining pollution has driven evolution of elevated copper tolerance in the impacted population of S. marinoi. Assays of 58 strains originating from sediment resting stages revealed no difference in the average tolerance to copper between the two populations. However, variation within populations was greater at the mining site, with three strains displaying hyper-tolerant phenotypes. In an artificial evolution experiment, we used a novel intraspecific metabarcoding locus to track selection and quantify fitness of all 58 strains during co-cultivation in one control and one toxic copper treatment. As expected, the hyper-tolerant strains enabled rapid evolution of copper tolerance in the mining-exposed population through selection on available strain diversity. Within 42 days, in each experimental replicate a single strain dominated (30%-99% abundance) but different strains dominated the different treatments. The reference population developed tolerance beyond expectations primarily due to slowly developing plastic response in one strain, suggesting that different modes of copper tolerance are present in the two populations. Our findings provide novel empirical evidence that standing genetic diversity of phytoplankton resting stage allows populations to evolve rapidly (20-50 generations) and flexibly on timescales relevant for seasonal bloom progressions.

2.
J Eukaryot Microbiol ; 70(4): e12975, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36972021

RESUMO

The health of coastal marine environments is severely declining with global changes. Proxies, such as those based on microeukaryote communities, can record biodiversity and ecosystem responses. However, conventional studies rely on microscopic observations of limited taxonomic range and size fraction, missing putatively ecologically informative community components. Here, we tested molecular tools to survey foraminiferal biodiversity in a fjord system (Sweden) on spatial and temporal scales: Alpha and beta diversity responses to natural and anthropogenic environmental trends were assessed and variability of foraminiferal environmental DNA (eDNA) compared to morphology-based data. The identification of eDNA-obtained taxonomic units was aided by single-cell barcoding. Our study revealed wide diversity, including typical morphospecies recognized in the fjords, and so-far unrecognized taxa. DNA extraction method impacted community composition outputs significantly. DNA extractions of 10 g sediment more reliably represented present diversity than of 0.5-g samples and, thus, are preferred for environmental assessments in this region. Alpha- and beta diversity of 10-g extracts correlated with bottom-water salinity similar to morpho-assemblage diversity changes. Sub-annual environmental variability resolved only partially, indicating damped sensitivity of foraminiferal communities on short timescales using established metabarcoding techniques. Systematically addressing the current limitations of morphology-based and metabarcoding studies may strongly improve future biodiversity and environmental assessments.


Assuntos
DNA Ambiental , Foraminíferos , Ecossistema , Estuários , DNA Ambiental/genética , Foraminíferos/genética , Monitoramento Ambiental/métodos , Biodiversidade , DNA , Código de Barras de DNA Taxonômico
3.
Environ Microbiol ; 21(1): 125-141, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30277305

RESUMO

The assimilation of inorganic compounds in foraminiferal metabolism compared to predation or organic matter assimilation is unknown. Here, we investigate possible inorganic-compound assimilation in Nonionellina labradorica, a common kleptoplastidic benthic foraminifer from Arctic and North Atlantic sublittoral regions. The objectives were to identify the source of the foraminiferal kleptoplasts, assess their photosynthetic functionality in light and darkness and investigate inorganic nitrogen and sulfate assimilation. We used DNA barcoding of a ~ 830 bp fragment from the SSU rDNA to identify the kleptoplasts and correlated transmission electron microscopy and nanometre-scale secondary ion mass spectrometry (TEM-NanoSIMS) isotopic imaging to study 13 C-bicarbonate, 15 N-ammonium and 34 S-sulfate uptake. In addition, respiration rate measurements were determined to assess the response of N. labradorica to light. The DNA sequences established that over 80% of the kleptoplasts belonged to Thalassiosira (with 96%-99% identity), a cosmopolitan planktonic diatom. TEM-NanoSIMS imaging revealed degraded cytoplasm and an absence of 13 C assimilation in foraminifera exposed to light. Oxygen measurements showed higher respiration rates under light than dark conditions, and no O2 production was detected. These results indicate that the photosynthetic pathways in N. labradorica are not functional. Furthermore, N. labradorica assimilated both 15 N-ammonium and 34 S-sulfate into its cytoplasm, which suggests that foraminifera might have several ammonium or sulfate assimilation pathways, involving either the kleptoplasts or bona fide foraminiferal pathway(s) not yet identified.


Assuntos
Carbono/metabolismo , Ecossistema , Foraminíferos/metabolismo , Nitrogênio/metabolismo , Enxofre/metabolismo , Citoplasma/metabolismo , Foraminíferos/classificação , Foraminíferos/genética , Foraminíferos/efeitos da radiação , Luz , Fotossíntese , Filogenia
4.
ISME J ; 16(2): 511-520, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34446855

RESUMO

Despite widespread metal pollution of coastal ecosystems, little is known of its effect on marine phytoplankton. We designed a co-cultivation experiment to test if toxic dose-response relationships can be used to predict the competitive outcome of two species under metal stress. Specifically, we took into account intraspecific strain variation and selection. We used 72 h dose-response relationships to model how silver (Ag), cadmium (Cd), and copper (Cu) affect both intraspecific strain selection and competition between taxa in two marine diatoms (Skeletonema marinoi and Thalassiosira baltica). The models were validated against 10-day co-culture experiments, using four strains per species. In the control treatment, we could predict the outcome using strain-specific growth rates, suggesting low levels of competitive interactions between the species. Our models correctly predicted which species would gain a competitive advantage under toxic stress. However, the absolute inhibition levels were confounded by the development of chronic toxic stress, resulting in a higher long-term inhibition by Cd and Cu. We failed to detect species differences in average Cu tolerance, but the model accounting for strain selection accurately predicted a competitive advantage for T. baltica. Our findings demonstrate the importance of incorporating multiple strains when determining traits and when performing microbial competition experiments.


Assuntos
Diatomáceas , Cobre/toxicidade , Diatomáceas/genética , Ecossistema , Fitoplâncton/genética
5.
ACS Omega ; 7(39): 35102-35108, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36211069

RESUMO

Black carbon (BC), spheroidal carbonaceous particles (SCP), and polycyclic aromatic hydrocarbons (PAH) are carbonaceous pollutants affecting the climate, environment, and human health. International regulations limit their emissions, and the present emissions are followed by monitoring programs. However, the monitoring programs have limited spatio-temporal coverage and only span the last decades. We can extend the knowledge of historical emission rates by measuring pollution levels in radiometrically dated marine and lacustrine sediment sequences. Here we present measurements of BC, SCP, and PAH from a sediment sequence sampled in the Öresund strait, between Denmark and Sweden and dated back to CE 1850. Our data show a massive increase in the burial rates of all measured pollutants starting in the 1940s. The pollution deposition peaked in the 1970-1980s and declined through the 1990s. However, the declining trend was reversed in the 2000s. Source appointment of PAHs shows a relatively higher contribution of emissions from wood-burning since CE 2000. This coincides with a change towards the increased use of biomass for both municipal and regional energy production in Scandinavia. Our results demonstrate that changes in energy production have caused changes in the delivery of carbonaceous pollution to marine environments. The increase in particle emissions from wood burning is potentially posing a future environmental and health risk.

6.
Sci Adv ; 7(22)2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34039603

RESUMO

Oceanic deoxygenation is increasingly affecting marine ecosystems; many taxa will be severely challenged, yet certain nominally aerobic foraminifera (rhizarian protists) thrive in oxygen-depleted to anoxic, sometimes sulfidic, sediments uninhabitable to most eukaryotes. Gene expression analyses of foraminifera common to severely hypoxic or anoxic sediments identified metabolic strategies used by this abundant taxon. In field-collected and laboratory-incubated samples, foraminifera expressed denitrification genes regardless of oxygen regime with a putative nitric oxide dismutase, a characteristic enzyme of oxygenic denitrification. A pyruvate:ferredoxin oxidoreductase was highly expressed, indicating the capability for anaerobic energy generation during exposure to hypoxia and anoxia. Near-complete expression of a diatom's plastid genome in one foraminiferal species suggests kleptoplasty or sequestration of functional plastids, conferring a metabolic advantage despite the host living far below the euphotic zone. Through a unique integration of functions largely unrecognized among "typical" eukaryotes, benthic foraminifera represent winning microeukaryotes in the face of ongoing oceanic deoxygenation.

7.
Aquat Toxicol ; 226: 105551, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32707232

RESUMO

Strains of microalgae vary in traits between species and populations due to adaptation or stochastic processes. Traits of individual strains may also vary depending on the acclimatization state and external forces, such as abiotic stress. In this study we tested how metal tolerance differs among marine diatoms at three organizational levels: species, populations, and strains. At the species level we compared two pelagic Baltic Sea diatoms (Skeletonema marinoi and Thalassiosira baltica). We found that the between-species differences in tolerance (EC50) to the biologically active metals (Cu, Co, Ni, and Zn) was similar to that within-species. In contrast, the two species differed significantly in tolerance towards the non-essential metals, Ag (three-fold higher in T. baltica), Pb and Cd (two and three-fold higher in S. marinoi). At the population level, we found evidence that increased tolerance against Cu and Co (17 and 41 % higher EC50 on average, respectively) had evolved in a S. marinoi population subjected to historical mining activity. On a strain level we demonstrate how the growth phase of cultures (i.e., cellular densities above exponential growth) modulated dose-response relationships to Ag, Cd, Co, Cu, and Zn. Specifically, the EC50's were reduced by 10-60 % in non-exponentially growing S. marinoi (strain RO5AC), depending on metal. For the essential metals these differences were often larger than the average differences between the two species and populations. Consequently, without careful experimental design, interactions between nutrient limitation and metal stress may interfere with detection of small, but evolutionary and ecologically important, differences in tolerance between microalgae. To avoid such artifacts, we outline a semi-continuous cultivation approach that maintains, and empirically tests, that exponential growth is achieved. We argue that such an approach is essential to enable comparison of population or strain differences in tolerance using dose-response tests on cultures of microalgae.


Assuntos
Aclimatação/efeitos dos fármacos , Diatomáceas/crescimento & desenvolvimento , Metais Pesados/toxicidade , Microalgas/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade , Diatomáceas/efeitos dos fármacos , Microalgas/efeitos dos fármacos , Mineração , Dinâmica Populacional , Especificidade da Espécie
8.
Front Microbiol ; 11: 604979, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33343548

RESUMO

Nitrogen availability often limits biological productivity in marine systems, where inorganic nitrogen, such as ammonium is assimilated into the food web by bacteria and photoautotrophic eukaryotes. Recently, ammonium assimilation was observed in kleptoplast-containing protists of the phylum foraminifera, possibly via the glutamine synthetase/glutamate synthase (GS/GOGAT) assimilation pathway imported with the kleptoplasts. However, it is not known if the ubiquitous and diverse heterotrophic protists have an innate ability for ammonium assimilation. Using stable isotope incubations (15N-ammonium and 13C-bicarbonate) and combining transmission electron microscopy (TEM) with quantitative nanoscale secondary ion mass spectrometry (NanoSIMS) imaging, we investigated the uptake and assimilation of dissolved inorganic ammonium by two heterotrophic foraminifera; a non-kleptoplastic benthic species, Ammonia sp., and a planktonic species, Globigerina bulloides. These species are heterotrophic and not capable of photosynthesis. Accordingly, they did not assimilate 13C-bicarbonate. However, both species assimilated dissolved 15N-ammonium and incorporated it into organelles of direct importance for ontogenetic growth and development of the cell. These observations demonstrate that at least some heterotrophic protists have an innate cellular mechanism for inorganic ammonium assimilation, highlighting a newly discovered pathway for dissolved inorganic nitrogen (DIN) assimilation within the marine microbial loop.

9.
J Clin Endocrinol Metab ; 94(2): 639-44, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19050057

RESUMO

CONTEXT: There is considerable individual variation in the clinical response to GH replacement therapy in GH deficient (GHD) adults. Useful predictors of treatment response are lacking. OBJECTIVE: The aim of the study was to assess the influence of the exon 3-deleted (d3-GHR) and full-length (fl-GHR) GH receptor isoforms on the response to GH replacement therapy in adults with severe GHD. DESIGN AND PATIENTS: A total of 124 adult GHD patients (79 men; median age, 50 yr) were studied before and after 12 months of GH therapy. GHD patients were divided into those bearing fl/fl alleles (group 1) and those bearing at least one d3-GHR allele (group 2), and the genotype was related to the effects of GH therapy on IGF-I levels and total body fat (BF). INTERVENTION: GH dose was individually titrated to obtain normal serum IGF-I levels. MAIN OUTCOME MEASURES: GHR genotype was determined by PCR amplification, IGF-I levels by immunoassay, and BF by a four-compartment model. RESULTS: Seventy-two (58%) patients had fl/fl genotype and were classified as group 1, whereas 52 (42%) had at least one d3-GHR allele and were classified as group 2 (40 were heterozygous and 12 were homozygous). At baseline, there were no significant differences in the study groups. Changes in IGF-I and BF after 12 months of GH treatment did not differ significantly between the two genotype groups. CONCLUSION: The presence of d3-GHR allele did not influence the response to GH replacement therapy in our cohort of adults with severe GHD.


Assuntos
Transtornos do Crescimento/tratamento farmacológico , Transtornos do Crescimento/genética , Hormônio do Crescimento Humano/uso terapêutico , Polimorfismo Genético/fisiologia , Receptores da Somatotropina/genética , Adolescente , Adulto , Idoso , Éxons , Feminino , Deleção de Genes , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/deficiência , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
10.
Endocr J ; 56(4): 601-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19352053

RESUMO

The aims were assessing liver function tests (LFT) in women with congenital adrenal hyperplasia (CAH) on glucocorticoids. Sixty-one women with genetically verified CAH due to 21-hydroxylase deficiency, aged 18-63 years were compared to 61 controls. Serum alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transpeptidase (GGT), anthropometry and fat mass (dual energy X-ray absorptiometry) were measured. ALT and GGT were higher in the entire patient group (p=0.01 and 0.002); AST, GGT and ALP in patients > or =30 years (p=0.007-0.045); all LFT in salt-wasting (p<0.001-0.042); GGT in simple virilizing (p=0.008); ALT, GGT and ALP in Null/Null genotype (p=0.018-0.040); ALT and GGT in I2splice genotype (p<0.001 and 0.011). Using a recently proposed cut-off level for ALT (>0.317 microkat/L), 54% of patients vs 23% of controls had elevated levels (p=0.028). In patients, GGT and ALP correlated with waist circumference and with total body and trunk fat (r=0.274-0.406, p=0.001-0.043). However, ALT, GGT and ALP were increased even in non-obese patients (waist circumference < or =88 cm and body mass index <30 kg/m(2)) (p=0.012-0.045) mainly attributed to the patients > or =30 years who also demonstrated elevated insulin levels and HOMA-indices. In conclusion, compared with controls, women with CAH have higher LFT, in particular patients > or =30 years and those with severe forms, probably reflecting a higher lifetime glucocorticoid exposure. LFT were positively correlated to measurements of body fat. These women might have increased frequency of NAFLD. The finding of higher LFT also in non-obese patients suggests that not only central obesity but also glucocorticoids per se may influence.


Assuntos
Hiperplasia Suprarrenal Congênita/enzimologia , Fígado/enzimologia , Adolescente , Adulto , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Aspartato Aminotransferases/sangue , Glicemia/metabolismo , Feminino , Humanos , Insulina/sangue , Testes de Função Hepática , Pessoa de Meia-Idade , Esteroide 21-Hidroxilase , Circunferência da Cintura , gama-Glutamiltransferase/sangue
11.
BMJ Open ; 9(11): e031168, 2019 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-31685507

RESUMO

INTRODUCTION: Cognitive impairment and reduced well-being are common manifestations of Graves' disease (GD). These symptoms are not only prevalent during the active phase of the disease but also often prevail for a long time after hyperthyroidism is considered cured. The pathogenic mechanisms involved in these brain-derived symptoms are currently unknown. The overall aim of the CogThy study is to identify the mechanism behind cognitive impairment to be able to recognise GD patients at risk. METHODS AND ANALYSIS: The study is a longitudinal, single-centre, case-controlled study conducted in Göteborg, Sweden on premenopausal women with newly diagnosed GD. The subjects are examined: at referral, at inclusion and then every 3.25 months until 15 months. Examinations include: laboratory measurements; eye evaluation; neuropsychiatric and neuropsychological testing; structural MRI of the whole brain, orbits and medial temporal lobe structures; functional near-infrared spectroscopy of the cerebral prefrontal cortex and self-assessed quality of life questionnaires. The primary outcome measure is the change in medial temporal lobe structure volume. Secondary outcome measures include neuropsychological, neuropsychiatric, hormonal and autoantibody variables. The study opened for inclusion in September 2012 and close for inclusion in October 2019. It will provide novel information on the effect of GD on medial temporal lobe structures and cerebral cortex functionality as well as whether these changes are associated with cognitive and affective impairment, hormonal levels and/or autoantibody levels. It should lead to a broader understanding of the underlying pathogenesis and future treatment perspectives. ETHICS AND DISSEMINATION: The study has been reviewed and approved by the Regional Ethical Review Board in Göteborg, Sweden. The results will be actively disseminated through peer-reviewed journals, national and international conference presentations and among patient organisations after an appropriate embargo time. TRIAL REGISTRATION NUMBER: 44321 at the public project database for research and development in Västra Götaland County, Sweden (https://www.researchweb.org/is/vgr/project/44321).


Assuntos
Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Doença de Graves/diagnóstico por imagem , Fadiga Mental/diagnóstico por imagem , Encéfalo/fisiopatologia , Estudos de Casos e Controles , Circulação Cerebrovascular , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Feminino , Neuroimagem Funcional , Doença de Graves/fisiopatologia , Doença de Graves/psicologia , Humanos , Estudos Longitudinais , Fadiga Mental/fisiopatologia , Fadiga Mental/psicologia , Testes Neuropsicológicos , Córtex Pré-Frontal/diagnóstico por imagem , Pré-Menopausa , Qualidade de Vida , Espectroscopia de Luz Próxima ao Infravermelho , Suécia , Lobo Temporal/diagnóstico por imagem
12.
Ambio ; 48(8): 816-830, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30430407

RESUMO

Major climate and ecological changes affect the world's oceans leading to a number of responses including increasing water temperatures, changing weather patterns, shrinking ice-sheets, temperature-driven shifts in marine species ranges, biodiversity loss and bleaching of coral reefs. In addition, ocean pH is falling, a process known as ocean acidification (OA). The root cause of OA lies in human policies and behaviours driving society's dependence on fossil fuels, resulting in elevated CO2 concentrations in the atmosphere. In this review, we detail the state of knowledge of the causes of, and potential responses to, OA with particular focus on Swedish coastal seas. We also discuss present knowledge gaps and implementation needs.


Assuntos
Ecossistema , Água do Mar , Dióxido de Carbono , Mudança Climática , Recifes de Corais , Humanos , Concentração de Íons de Hidrogênio , Oceanos e Mares
13.
Ambio ; 48(8): 831-854, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30506502

RESUMO

Ocean temperatures are rising; species are shifting poleward, and pH is falling (ocean acidification, OA). We summarise current understanding of OA in the brackish Baltic-Skagerrak System, focussing on the direct, indirect and interactive effects of OA with other anthropogenic drivers on marine biogeochemistry, organisms and ecosystems. Substantial recent advances reveal a pattern of stronger responses (positive or negative) of species than ecosystems, more positive responses at lower trophic levels and strong indirect interactions in food-webs. Common emergent themes were as follows: OA drives planktonic systems toward the microbial loop, reducing energy transfer to zooplankton and fish; and nutrient/food availability ameliorates negative impacts of OA. We identify several key areas for further research, notably the need for OA-relevant biogeochemical and ecosystem models, and understanding the ecological and evolutionary capacity of Baltic-Skagerrak ecosystems to respond to OA and other anthropogenic drivers.


Assuntos
Ecossistema , Água do Mar , Animais , Países Bálticos , Ecologia , Concentração de Íons de Hidrogênio , Oceanos e Mares
14.
J Clin Endocrinol Metab ; 93(2): 380-6, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18029470

RESUMO

CONTEXT: In congenital adrenal hyperplasia (CAH) caused by different mutations, feminizing surgery is mostly performed in childhood, and many patients are lost to follow-up. OBJECTIVE/PATIENTS: A follow-up study on 62 CAH women aged 18-63 yr and 62 age-matched controls to correlate findings of both operative method and mutation was performed. DESIGN: Semistructured interviews were performed in cases and controls, as well as a gynecological examination in the cases. The results were correlated with disease-causing mutations and earlier surgical procedures if performed. SETTING: The study was conducted at university hospital referral clinics. MAIN OUTCOME MEASURES: Gynecological examination in all cases correlated to previous surgery (n = 49), type of mutation, and questionnaire responses. RESULTS: Half of the CAH women claimed that the disease affected their sex life. The women were less satisfied with their genitals, whether operated or not. Clitoris size and functions were affected by the surgical method. Five women had a clinically evident vaginal stenosis on examination. However, almost half of patients experienced a narrow vagina. The overall psychosexual aspects of life were affected in these patients with later sexual debut, fewer pregnancies and children, and an increased incidence of homosexuality. These quality of life factors were correlated to the severity of the mutations. CONCLUSIONS: The overall quality of life in adult women with CAH is affected both by the type of mutation and operative procedure. Indications for clitoroplasty should be restrictive. Medical, surgical, and psychological treatment should be centralized.


Assuntos
Hiperplasia Suprarrenal Congênita/genética , Hiperplasia Suprarrenal Congênita/cirurgia , Clitóris/cirurgia , Esteroide 21-Hidroxilase/genética , Vagina/cirurgia , Adolescente , Hiperplasia Suprarrenal Congênita/enzimologia , Hiperplasia Suprarrenal Congênita/psicologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Mutação , Desenvolvimento Psicossexual , Qualidade de Vida
15.
Mar Environ Res ; 138: 36-45, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29680163

RESUMO

Coastal areas display natural large environmental variability such as frequent changes in salinity, pH, and carbonate chemistry. Anthropogenic impacts - especially ocean acidification - increase this variability, which may affect the living conditions of coastal species, particularly, calcifiers. We performed culture experiments on living benthic foraminifera to study the combined effects of lowered pH and salinity on the calcification abilities and survival of the coastal, calcitic species Ammonia sp. and Elphidium crispum. We found that in open ocean conditions (salinity ∼35) and lower pH than usual values for these species, the specimens displayed resistance to shell (test) dissolution for a longer time than in brackish conditions (salinity ∼5 to 20). However, the response was species specific as Ammonia sp. specimens survived longer than E. crispum specimens when placed in the same conditions of salinity and pH. Living, decalcified juveniles of Ammonia sp. were observed and we show that desalination is one cause for the decalcification. Finally, we highlight the ability of foraminifera to survive under Ωcalc < 1, and that high salinity and [Ca2+] as building blocks are crucial for the foraminiferal calcification process.


Assuntos
Adaptação Fisiológica , Foraminíferos/fisiologia , Água do Mar/química , Calcificação Fisiológica , Carbonato de Cálcio , Monitoramento Ambiental , Foraminíferos/química , Concentração de Íons de Hidrogênio , Salinidade
16.
BMJ Open ; 8(4): e019945, 2018 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-29643159

RESUMO

INTRODUCTION: Iodine is essential for normal brain development. Moderate and severe fetal iodine deficiency results in substantial to serious developmental delay in children. Mild iodine deficiency in pregnancy is associated with neurodevelopmental deficits in the offspring, but evidence from randomised trials is lacking. The aim of the Swedish Iodine in Pregnancy and Development in Children study is to determine the effect of daily supplementation with 150 µg iodine during pregnancy on the offspring's neuropsychological development up to 14 years of age. METHODS AND ANALYSIS: Thyroid healthy pregnant women (n=1275: age range 18-40 years) at ≤12 weeks gestation will be randomly assigned to receive multivitamin supplements containing 150 µg iodine or non-iodine-containing multivitamin daily throughout pregnancy. As a primary outcome, IQ will be measured in the offspring at 7 years (Wechsler Intelligence Scale for Children-V). As secondary outcomes, IQ will be measured at 3.5 and 14 years, psychomotor development at 18 months and 7 years, and behaviour at 3.5, 7 and 14 years. Iodine status (urinary iodine concentration) will be measured during pregnancy and in the offspring at 3.5, 7 and 14 years. Thyroid function (thyroid hormones, thyroglobulin), and deiodinase type 2 polymorphisms will be measured during pregnancy and in the offspring at 7 and 14 years. Structural MRI or other relevant structural or functional brain imaging procedures will be performed in a subgroup of children at 7 and 14 years. Background and socioeconomic information will be collected at all follow-up times. ETHICS AND DISSEMINATION: This study is approved by the Ethics Committee in Göteborg, Sweden (Diary numbers: 431-12 approved 18 June 2012 (pregnancy part) and 1089-16 approved 8 February 2017 (children follow-up)). According to Swedish regulations, dietary supplements are governed by the National Food Agency and not by the Medical Product Agency. Therefore, there is no requirement for a monitoring committee and the National Food Agency does not perform any audits of trial conduct. The trial will be conducted in accordance with the Declaration of Helsinki. The participating sites will be contacted regarding important protocol changes, both orally and in writing, and the trial registry database will be updated accordingly. Study results will be presented at relevant conferences, and submitted to peer-reviewed journals with open access in the fields of endocrinology, paediatrics and nutrition. After the appropriate embargo period, the results will be communicated to participants, healthcare professionals at the maternal healthcare centres, the public and other relevant groups, such as the national guideline group for thyroid and pregnancy and the National Food Agency. TRIAL REGISTRATION NUMBER: NCT02378246; Pre-results.


Assuntos
Encéfalo , Suplementos Nutricionais , Inteligência , Iodo , Efeitos Tardios da Exposição Pré-Natal , Adolescente , Adulto , Encéfalo/efeitos dos fármacos , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Feminino , Humanos , Recém-Nascido , Iodo/administração & dosagem , Iodo/deficiência , Lactação , Gravidez , Complicações na Gravidez/tratamento farmacológico , Suécia , Adulto Jovem
17.
J Clin Endocrinol Metab ; 92(1): 110-6, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17032717

RESUMO

CONTEXT: The chronic, often supraphysiological glucocorticoid doses used in congenital adrenal hyperplasia (CAH) might increase morbidity in cardiovascular disease and diabetes. OBJECTIVE: Our aim was to assess risk factors for cardiovascular disease and diabetes in CAH women. SUBJECTS, METHODS, AND DESIGN: We compared 61 women, 18-63 yr, with CAH due to 21-hydroxylase deficiency with 61 age- and sex- matched controls. Twenty-seven were younger than 30 yr, and 34 were 30 yr or older. Anthropometry, fat and lean mass measured by dual-energy x-ray absorptiometry, serum lipids, insulin, and adrenocortical steroids were studied. MAIN OUTCOME MEASURE: Body composition and cardiovascular risk factors were the main outcome measures. RESULTS: Younger patients and controls had similar waist to hip ratio, lean and fat mass, and insulin. Older patients had higher waist to hip ratio, lean mass, and insulin than controls. Fat mass was similar to controls but higher than in younger patients. Lipid profiles were slightly more favorable in older patients than controls. Gestational diabetes was more common in patients (21% of pregnancies vs. 0, P < 0.026). Few older patients had hypertension, cardiovascular disease, or diabetes. Despite moderate glucocorticoid doses, most patients had suppressed androgens. CONCLUSIONS: No clear evidence of unfavorable cardiovascular risk factors were found. Increased fat mass and higher insulin levels were, however, found in patients older than 30 yr. High frequency of gestational diabetes is a risk marker for future diabetes. Lifelong follow-up, lifestyle modifications, and attempts to adjust and reduce the glucocorticoid doses seem important.


Assuntos
Hiperplasia Suprarrenal Congênita/metabolismo , Composição Corporal , Adolescente , Hiperplasia Suprarrenal Congênita/complicações , Adulto , Pressão Sanguínea , Índice de Massa Corporal , Peso Corporal , Doenças Cardiovasculares/etiologia , Sulfato de Desidroepiandrosterona/sangue , Diabetes Mellitus/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Esteroide 21-Hidroxilase/análise
18.
J Clin Endocrinol Metab ; 92(12): 4643-9, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17878254

RESUMO

CONTEXT: Patients with classical congenital adrenal hyperplasia (CAH) receive lifelong, often supraphysiological, glucocorticoid therapy. Pharmacological doses of glucocorticoids are an established risk factor for osteoporosis. OBJECTIVE: Our objective was to evaluate bone mineral density (BMD), fracture prevalence, and markers of bone metabolism in adult females with CAH. DESIGN: This was a cross-sectional observational study. SETTING: Tertiary care referral centers were used in this study. PARTICIPANTS: We studied 61 women, aged 18-63 yr, with genetically verified CAH due to 21-hydroxylase deficiency. They were patients with salt wasting (n = 27), simple virilizing (n = 28), and nonclassical 21-hydroxylase deficiency (n = 6). A total of 61 age-matched women were controls. MAIN OUTCOME MEASURES: History of fractures was recorded. Total body, lumbar spine, and femoral neck BMD were measured by dual-energy x-ray absorptiometry. The World Health Organization criteria for osteopenia and osteoporosis were used. Serum marker of bone resorption, beta-C telopeptide was studied. RESULTS: The mean glucocorticoid dose in hydrocortisone equivalents was 16.9 +/- 0.9 mg/m2. Patients had lower BMD than controls at all measured sites (P < 0.001). In patients younger than 30 yr old, 48% were osteopenic vs. 12% in controls (P < 0.009). In patients 30 yr or older, 73% were osteopenic or osteoporotic vs. 21% in controls (P < 0.001). BMD was similar in the two classical forms and had no obvious relationship to genotypes. beta-C-telopeptide was decreased in older patients. More fractures were reported in patients than controls (P < 0.001). The number of vertebrae and wrist fractures almost reached significance (P = 0.058). CONCLUSIONS: Women with CAH have low BMD and increased fracture risk. BMD should be monitored, adequate prophylaxis and treatment instituted, and glucocorticoid doses optimized from puberty.


Assuntos
Hiperplasia Suprarrenal Congênita/complicações , Hiperplasia Suprarrenal Congênita/epidemiologia , Densidade Óssea/genética , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/genética , Esteroide 21-Hidroxilase/genética , Hiperplasia Suprarrenal Congênita/enzimologia , Adulto , Biomarcadores , Osso e Ossos/metabolismo , Estudos de Coortes , Colágeno Tipo I/sangue , Feminino , Fraturas Ósseas/enzimologia , Genótipo , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Hormônios/sangue , Humanos , Mutação/fisiologia , Osteoporose/epidemiologia , Osteoporose/genética , Hormônio Paratireóideo/sangue
19.
Horm Res ; 68 Suppl 5: 182-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18174742

RESUMO

BACKGROUND: Glucocorticoid (GC) deficiency is a consequence of various disorders that are by themselves rare. Because of this low prevalence, the low cost of GC replacement therapy and the belief that existing outcomes are good, there has been little interest in development of new and improved pharmaceutical products for treatment of GC deficiency. However, GC replacement therapy is complex: diurnal variation of endogenous cortisol must be replicated, GC needs may change during times of physical and psychological stress and there is no biomarker of its action that can be used to monitor individual dose response. CURRENT LIMITATIONS: Recent data suggest that the outcome of established long-term GC replacement therapy may not be as good as previously believed. Short-acting GCs such as hydrocortisone (HC) and cortisone acetate for replacement therapy require 2 to 3 administrations per day. DEVELOPING ALTERNATIVES: Drug delivery system technologies are now available that could permit design and manufacture of a formulation that could accommodate once-daily administration of HC. Such a formulation would enable more physiological serum cortisol-time profiles than are possible with currently available formulations. This short review provides some background on GC replacement therapy, along with recent data on the outcome of patient groups with GC insufficiency, and briefly discusses some general principles for a controlled-release ('long-acting') HC formulation.


Assuntos
Glucocorticoides/deficiência , Glucocorticoides/uso terapêutico , Terapia de Reposição Hormonal , Hidrocortisona/administração & dosagem , Insuficiência Adrenal/mortalidade , Química Farmacêutica , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Esquema de Medicação , Sistemas de Liberação de Medicamentos , Humanos , Hidrocortisona/uso terapêutico
20.
Minerva Med ; 108(2): 147-158, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28001012

RESUMO

Iodine nutrition is a result of geological conditions, iodine fortification and monitoring strategies within a country together with the dietary habits of the population. This review summarizes the basis for the current iodine situation in the Scandinavian countries in order to identify gaps in knowledge, determine necessary future steps, highlight landmarks in Scandinavian iodine research and consider ongoing studies in Scandinavian countries with high international impact. Historically, iodine deficiency disorders such as goiter were common in Norway and Sweden, but not in Denmark. Different strategies have been used in Scandinavia to improve iodine nutrition. The major source of iodine is iodized salt in Sweden and from milk and dairy products in Norway. In Denmark, drinking water, milk, dairy products and iodized salt used in commercial production of bread are the important sources of iodine. The current iodine status in Scandinavia is not optimal and action is ongoing to increase iodination in Denmark, where there is mild iodine deficiency in the general population. Data from all three countries indicate insufficient iodine nutrition during pregnancy and there is a need for data from children, adolescents and young women. Monitoring a population's iodine status and dietary iodine sources is necessary to secure iodine nutrition in Scandinavia. Ongoing studies in Scandinavia will contribute significantly to the knowledge about the effects of mild to moderate iodine deficiency.


Assuntos
Suplementos Nutricionais , Iodo/administração & dosagem , Iodo/deficiência , Oligoelementos/administração & dosagem , Oligoelementos/deficiência , Adolescente , Adulto , Criança , Dinamarca/epidemiologia , Feminino , Geografia Médica , Bócio Endêmico/epidemiologia , Bócio Endêmico/prevenção & controle , Humanos , Iodo/urina , Masculino , Noruega/epidemiologia , Gravidez , Fatores Sexuais , Cloreto de Sódio na Dieta/administração & dosagem , Suécia/epidemiologia , Oligoelementos/urina
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