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1.
Glob Chang Biol ; 30(5): e17334, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38780465

RESUMO

The crises of climate change and biodiversity loss are interlinked and must be addressed jointly. A proposed solution for reducing reliance on fossil fuels, and thus mitigating climate change, is the transition from conventional combustion-engine to electric vehicles. This transition currently requires additional mineral resources, such as nickel and cobalt used in car batteries, presently obtained from land-based mines. Most options to meet this demand are associated with some biodiversity loss. One proposal is to mine the deep seabed, a vast, relatively pristine and mostly unexplored region of our planet. Few comparisons of environmental impacts of solely expanding land-based mining versus extending mining to the deep seabed for the additional resources exist and for biodiversity only qualitative. Here, we present a framework that facilitates a holistic comparison of relative ecosystem impacts by mining, using empirical data from relevant environmental metrics. This framework (Environmental Impact Wheel) includes a suite of physicochemical and biological components, rather than a few selected metrics, surrogates, or proxies. It is modified from the "recovery wheel" presented in the International Standards for the Practice of Ecological Restoration to address impacts rather than recovery. The wheel includes six attributes (physical condition, community composition, structural diversity, ecosystem function, external exchanges and absence of threats). Each has 3-5 sub attributes, in turn measured with several indicators. The framework includes five steps: (1) identifying geographic scope; (2) identifying relevant spatiotemporal scales; (3) selecting relevant indicators for each sub-attribute; (4) aggregating changes in indicators to scores; and (5) generating Environmental Impact Wheels for targeted comparisons. To move forward comparisons of land-based with deep seabed mining, thresholds of the indicators that reflect the range in severity of environmental impacts are needed. Indicators should be based on clearly articulated environmental goals, with objectives and targets that are specific, measurable, achievable, relevant, and time bound.


Assuntos
Mineração , Biodiversidade , Ecossistema , Meio Ambiente , Conservação dos Recursos Naturais , Mudança Climática
2.
EBioMedicine ; 94: 104692, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37451904

RESUMO

BACKGROUND: People with Down syndrome (DS) show clinical signs of accelerated ageing. Causative mechanisms remain unknown and hypotheses range from the (essentially untreatable) amplified-chromosomal-instability explanation, to potential actions of individual supernumerary chromosome-21 genes. The latter explanation could open a route to therapeutic amelioration if the specific over-acting genes could be identified and their action toned-down. METHODS: Biological age was estimated through patterns of sugar molecules attached to plasma immunoglobulin-G (IgG-glycans, an established "biological-ageing-clock") in n = 246 individuals with DS from three European populations, clinically characterised for the presence of co-morbidities, and compared to n = 256 age-, sex- and demography-matched healthy controls. Isogenic human induced pluripotent stem cell (hiPSCs) models of full and partial trisomy-21 with CRISPR-Cas9 gene editing and two kinase inhibitors were studied prior and after differentiation to cerebral organoids. FINDINGS: Biological age in adults with DS is (on average) 18.4-19.1 years older than in chronological-age-matched controls independent of co-morbidities, and this shift remains constant throughout lifespan. Changes are detectable from early childhood, and do not require a supernumerary chromosome, but are seen in segmental duplication of only 31 genes, along with increased DNA damage and decreased levels of LaminB1 in nucleated blood cells. We demonstrate that these cell-autonomous phenotypes can be gene-dose-modelled and pharmacologically corrected in hiPSCs and derived cerebral organoids. Using isogenic hiPSC models we show that chromosome-21 gene DYRK1A overdose is sufficient and necessary to cause excess unrepaired DNA damage. INTERPRETATION: Explanation of hitherto observed accelerated ageing in DS as a developmental progeroid syndrome driven by DYRK1A overdose provides a target for early pharmacological preventative intervention strategies. FUNDING: Main funding came from the "Research Cooperability" Program of the Croatian Science Foundation funded by the European Union from the European Social Fund under the Operational Programme Efficient Human Resources 2014-2020, Project PZS-2019-02-4277, and the Wellcome Trust Grants 098330/Z/12/Z and 217199/Z/19/Z (UK). All other funding is described in details in the "Acknowledgements".


Assuntos
Síndrome de Down , Células-Tronco Pluripotentes Induzidas , Adulto , Humanos , Envelhecimento , Diferenciação Celular , Síndrome de Down/genética , Quinases Dyrk
3.
Sci Total Environ ; 852: 158162, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35988633

RESUMO

Increased suspended sediment concentrations (SSC) are a major stressor across aquatic habitats. Here, the literature was synthesized to show that animal responses to increases in relative SSC (test concentration/natural background concentration) were similar in type and negative across different shallow-water (marine, estuarine, freshwater) habitats. Further, animal sensitivities are similar across habitats based on relative SSC and occur starting at low relative SSC increases in all habitats despite differences in natural background SSC. Based upon these similarities in relative SSC sensitivities, deep-sea sensitivity values for acute exposure to increased SSC, where empirical data are almost non-existent, were estimated. Because of the low natural SSC in deep sea environments, very small increases in absolute SSC could result in acute effects. How the methods and results can be used to inform regulatory thresholds are discussed. Because of the large variability in shallow water datasets and differences between deep-sea and shallow-water habitats, deep-sea specific data are needed to verify the estimates and improve their precision. Following the precautionary principle and the results presented here, it is recommended that the threshold for acute plume impacts is set very close to natural background levels.


Assuntos
Monitoramento Ambiental , Água , Animais , Monitoramento Ambiental/métodos , Mineração , Ecossistema
4.
J Fish Biol ; 84(5): 1519-26, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24697612

RESUMO

Paraliparis hawaiiensis n.sp. is described from the north-western Hawaiian Islands from two specimens collected at 2196 and 3055 m. It differs from other North Pacific Ocean species in its chin pore arrangement, tooth pattern and body proportions. Although liparid specimens have previously been collected from Hawaii, they were undescribed and are now lost. Therefore, this is the first liparid species described from the archipelago. In situ photographs of Hawaiian snailfishes are also shown and discussed here.


Assuntos
Perciformes/anatomia & histologia , Perciformes/classificação , Animais , Havaí
5.
J Fish Biol ; 83(6): 1592-612, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24298953

RESUMO

Owing to the paucity of data on the red muscle of deep-sea fishes, the goal of this study was to determine the proportions of red muscle in demersal fishes and its enzymatic activities to characterize how routine swimming abilities change with depths of occurrence. Cross sectional analysis of the trunk musculature was used to evaluate the proportion of red muscle in 38 species of Californian demersal fishes living at depths between 100 and 3000 m. The activity of metabolic enzymes was also assayed in a sub-set of 18 species. Benthic fishes had lower proportions of red muscle and lower metabolic enzyme activities than benthopelagic species. Mean proportion of red muscle declined significantly with depth with the greatest range of values in shallow waters and species with low proportions found at all depths. This suggested that while sedentary species occur at all depths, the most active species occur in shallow waters. Citrate synthase activity declined significantly with depth across all species, indicating that the mass-specific metabolic capacity of red muscle is lower in deep-sea species. These patterns may be explained by coupling of red and white muscle physiologies, a decrease in physical energy of the environment with depth or by the prevalence of anguilliform body forms and swimming modes in deep-living species.


Assuntos
Peixes/fisiologia , Músculos/enzimologia , Natação/fisiologia , Animais , California , Citrato (si)-Sintase/metabolismo , Meio Ambiente , Oceano Pacífico
7.
Eur Respir J ; 36(5): 995-1001, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20223919

RESUMO

The 2008-2013 World Health Organization (WHO) action plan on noncommunicable diseases (NCDs) includes chronic respiratory diseases as one of its four priorities. Major chronic respiratory diseases (CRDs) include asthma and rhinitis, chronic obstructive pulmonary disease, occupational lung diseases, sleep-disordered breathing, pulmonary hypertension, bronchiectiasis and pulmonary interstitial diseases. A billion people suffer from chronic respiratory diseases, the majority being in developing countries. CRDs have major adverse effects on the life and disability of patients. Effective intervention plans can prevent and control CRDs, thus reducing morbidity and mortality. A prioritised research agenda should encapsulate all of these considerations in the frame of the global fight against NCDs. This requires both CRD-targeted interventions and transverse NCD programmes which include CRDs, with emphasis on health promotion and disease prevention.


Assuntos
Saúde Global , Pneumopatias/prevenção & controle , Pneumopatias/terapia , Pesquisa/tendências , Organização Mundial da Saúde , Doença Crônica , Comorbidade , Humanos , Pneumopatias/epidemiologia , Prevalência
8.
Eur Respir J ; 31(1): 143-78, 2008 01.
Artigo em Inglês | MEDLINE | ID: mdl-18166595

RESUMO

Asthma is a serious health problem throughout the world. During the past two decades, many scientific advances have improved our understanding of asthma and ability to manage and control it effectively. However, recommendations for asthma care need to be adapted to local conditions, resources and services. Since it was formed in 1993, the Global Initiative for Asthma, a network of individuals, organisations and public health officials, has played a leading role in disseminating information about the care of patients with asthma based on a process of continuous review of published scientific investigations. A comprehensive workshop report entitled "A Global Strategy for Asthma Management and Prevention", first published in 1995, has been widely adopted, translated and reproduced, and forms the basis for many national guidelines. The 2006 report contains important new themes. First, it asserts that "it is reasonable to expect that in most patients with asthma, control of the disease can and should be achieved and maintained," and recommends a change in approach to asthma management, with asthma control, rather than asthma severity, being the focus of treatment decisions. The importance of the patient-care giver partnership and guided self-management, along with setting goals for treatment, are also emphasised.


Assuntos
Asma/diagnóstico , Asma/prevenção & controle , Asma/terapia , Corticosteroides/farmacologia , Antiasmáticos/uso terapêutico , Asma/epidemiologia , Diagnóstico Diferencial , Gerenciamento Clínico , Saúde Global , Guias como Assunto , Humanos , Comunicação Interdisciplinar , Saúde Pública , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Pneumologia/métodos , Fatores de Risco
9.
Ned Tijdschr Geneeskd ; 148(38): 1870-1, 2004 Sep 18.
Artigo em Holandês | MEDLINE | ID: mdl-15497781

RESUMO

Altruistic motives and trust are central to scientific investigations involving people. These prompt volunteers to participate in clinical trials. However, publication bias and other causes of the failure to report trial results may lead to an overly positive view of medical interventions in the published evidence available. Registration of randomised controlled trials right from the start is therefore warranted. The International Committee of Medical Journal Editors has issued a statement to the effect that the 11 journals represented in the Committee will not consider publication of the results of trials that have not been registered in a publicly accessible register such as www.clinicaltrials.gov. Patients who voluntarily participate in clinical trials need to know that their contribution to better human healthcare is available for decision making in clinical practice.


Assuntos
Ensaios Clínicos como Assunto/normas , Políticas Editoriais , Publicações Periódicas como Assunto/normas , Sistema de Registros
10.
Genet Epidemiol ; 23(4): 335-48, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12432502

RESUMO

Interleukin 13 (IL-13) has been demonstrated to have a crucial role in animal models of allergy and asthma. In human case-control genetic-association studies, the Arg130Gln polymorphism has been associated with elevated total serum IgE and an asthma diagnosis in atopic and nonatopic individuals (Graves et al. [2000] J. Allergy Clin. Immunol. 105:506-513; Heinzmann et al. [2000] Hum. Mol. Genet. 9:549-559). To apply family-based association methods, we obtained DNA samples from 685 asthmatic children from 640 sibships and their parents in the Childhood Asthma Management Program (CAMP). Six hundred and sixty-six asthmatic children had complete phenotypic information and were used for this analysis. We performed quantitative association analysis using the transmission disequilibrium test (TDT) on 22 individual phenotypes and 5 grouped phenotypes relating to allergy, airway responsiveness, pulmonary function, bronchodilator responsiveness, and asthma severity, using genotypes at the Arg130Gln polymorphism of the IL-13 gene. A positive association was obtained between Arg130Gln and a grouped phenotype of allergy (consisting of the individual phenotypes of eosinophils, IgE, and positive skin tests), using FBAT-GEE, a multivariate extension of the family-based association test (Lange et al. [2002] Biostatistics 1:1-15). The three phenotypes were then evaluated individually and revealed a significant association between total eosinophil count and the Arg130Gln locus; there was a trend for association between total IgE and the Arg130Gln polymorphism. The Arg130Gln polymorphism is associated with an elevated eosinophil count as well as with a grouped allergy phenotype, in children with mild to moderate asthma. No evidence for association was found between Arg130Gln and airway responsiveness, asthma diagnosis, or asthma severity.


Assuntos
Asma/genética , Interleucina-13/genética , Polimorfismo Genético , Alérgenos/imunologia , Asma/imunologia , Distribuição de Qui-Quadrado , Criança , DNA/análise , Eosinófilos , Feminino , Genótipo , Humanos , Imunoglobulina E/genética , Imunoglobulina E/imunologia , Interleucina-13/imunologia , Desequilíbrio de Ligação , Masculino , Núcleo Familiar , Fenótipo , Reação em Cadeia da Polimerase , Testes de Função Respiratória , Índice de Gravidade de Doença
11.
Nitric Oxide ; 6(2): 236-41, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11890749

RESUMO

Nitric oxide (NO) plays an important role in a number of physiological processes in the airways, including host defense. Although the exact cellular and molecular source of the NO formation in airways is unknown, there is recent evidence that neuronal NO synthase (NOS1) contributes significantly to NO in the lower airways of cystic fibrosis (CF) patients. NOS1 protein has been shown to be expressed in nasal epithelium, suggesting an involvement of NOS1-derived NO in upper airway biology. We here hypothesized that nasal NO concentrations in CF patients are related to genotype variants in the NOS1 gene. Measurements of nasal NO concentration and pulmonary function were performed in 40 clinically stable CF patients. Genomic DNA from all patients was screened for an intronic AAT-repeat polymorphism in the NOS1 gene using polymerase chain reaction and simple sequence length polymorphism (SSLP) analysis. The allele size at that locus was significantly (P = 0.001) associated with upper airway NO. Mean (+/- SD) nasal NO concentrations were 40.5 +/- 5.2 ppb in CF patients (n = 12) with high repeat numbers (i.e., both alleles > or =12 repeats) and 72.6 +/- 7.4 ppb in patients (n = 28) with low repeat numbers (i.e., at least one allele <12 repeats). Furthermore, in the group of CF patients harboring NOS1 genotypes associated with low nasal NO, colonization of airways with P. aeruginosa was significantly more frequent than in patients with NOS1 genotypes associated high nasal NO concentrations (P = 0.0022). We conclude that (1) the variability in CF nasal NO levels are related to naturally occurring variants in the NOS1 gene, and (2) that nasal NOS1-derived NO affects the susceptibility of CF airways to infection with P. aeruginosa.


Assuntos
Fibrose Cística/genética , Óxido Nítrico Sintase/genética , Óxido Nítrico/metabolismo , Polimorfismo Genético , Adolescente , Adulto , Alelos , Criança , Fibrose Cística/enzimologia , Fibrose Cística/metabolismo , Feminino , Genótipo , Humanos , Masculino , Mucosa Nasal/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo I , Nariz/química , Fenótipo , Infecções por Pseudomonas/genética
12.
J Allergy Clin Immunol ; 108(6): 946-53, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11742272

RESUMO

BACKGROUND: Eotaxin, a CC chemokine expressed in the asthmatic lung, has been associated with impaired lung function. The role of its variant form is unknown. OBJECTIVE: The purpose of this study was to detect the population frequency and effects of a known single-nucleotide polymorphism in the eotaxin gene in which a threonine residue (THR(23)) is substituted for the wild-type alanine (ALA(23)) at the 23rd amino acid at the terminus of the peptide leader sequence. METHODS: We measured eotaxin protein secretion in 293 cells transfected with expression vectors and in PBMCs obtained from individuals bearing the alternative forms of the gene. A case-control study of plasma eotaxin levels and eosinophil counts, a comparison of baseline lung function by genotype in a population of 806 subjects with asthma, and a comparison of the allele frequency with a nonasthmatic population were performed. RESULTS: Human 293 cells and PBMCs with THR(23) variant eotaxin secreted significantly less eotaxin protein than did ALA(23)-bearing cells. In the case-control study, THR(23)-THR(23) individuals had lower plasma levels of eotaxin (310 [240-350] vs 420 [270-700] pg/mL; P < .05) and eosinophil counts (120 [5-220] vs 190 [110-470] cells/microL; P < .05) than ALA(23)-ALA(23) subjects; heterozygous subjects had intermediate levels. Higher levels of lung function were associated with THR(23) eotaxin (percent of predicted FEV(1), 65% +/- 3.5% [THR(23)-THR(23)] vs 58% +/- 0.9% [THR(23)-ALA(23)] and 56% +/- 0.5% [ALA(23)-ALA(23)]; P < .05). CONCLUSION: The THR(23) variant is associated with both decreased eosinophil counts and higher levels of lung function in subjects with asthma.


Assuntos
Asma/genética , Quimiocinas CC/genética , Adulto , Estudos de Casos e Controles , Células Cultivadas , Quimiocina CCL11 , Clonagem Molecular , Feminino , Genótipo , Humanos , Masculino , Mutação , Fenótipo , Polimorfismo Conformacional de Fita Simples
13.
Am J Respir Crit Care Med ; 164(10 Pt 2): S90-4, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11734475

RESUMO

The airway is exposed to a variety of mechanical stimuli, the most prominent of which is the acute compressive stress caused by bronchoconstriction. The folding of the airway wall into a rosette pattern during bronchoconstriction creates a complex stress field, with the highest stresses compressing the epithelial layer at the inner surface of the airway wall. The epithelial cells lining the airway possess the capacity to modulate the inflammatory environment of the airway wall, and produce factors that influence the recruitment, proliferation, and activity of fibroblasts and smooth muscle cells. A variety of in vitro studies have demonstrated that airway epithelial cells, along with lung fibroblasts and smooth muscle cells, are responsive to mechanical stimuli. Airway epithelial cells exposed to compressive stresses matched to those occurring in the constricted airway increase expression of genes relevant to airway remodeling, and increase the collagen synthesis of cocultured fibroblasts. These findings demonstrate that mechanical stress may contribute to the remodeling of the asthmatic airway.


Assuntos
Asma/patologia , Asma/fisiopatologia , Broncoconstrição , Pulmão/patologia , Estresse Mecânico , Animais , Asma/genética , Brônquios/metabolismo , Brônquios/patologia , Gatos , Células Cultivadas , Técnicas de Cocultura , Colágeno/biossíntese , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Expressão Gênica , Humanos , Pulmão/citologia , Pulmão/metabolismo , Músculo Liso/citologia , Músculo Liso/metabolismo , Músculo Liso/patologia , Coelhos , Ratos , Traqueia/metabolismo , Traqueia/patologia , Regulação para Cima
15.
Control Clin Trials ; 22(6 Suppl): 196S-206S, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11728624

RESUMO

Because there is reason to believe that genetic variants could account for different treatment responses in subjects with asthma, it is important to collect blood for genetic-analysis purposes when conducting clinical trials in asthma. This article describes issues related to maintaining subject confidentiality, tracking and shipping blood samples, quality control procedures at the laboratory performing the genotyping, and necessary data verification checks when implementing the genetic-analysis database for the Asthma Clinical Research Network.


Assuntos
Albuterol/análogos & derivados , Asma/genética , Ensaios Clínicos como Assunto/métodos , Comitês de Ética em Pesquisa , Agonistas Adrenérgicos beta/uso terapêutico , Albuterol/uso terapêutico , Asma/tratamento farmacológico , Confidencialidade , Genótipo , Humanos , Controle de Qualidade , Xinafoato de Salmeterol
19.
Chest ; 120(5): 1474-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11713122

RESUMO

STUDY OBJECTIVE: Beta(2)-adrenoceptor Gly16 polymorphism has been associated with asthma severity and beta(2)-adrenoceptor receptor downregulation, but not with the diagnosis of asthma. Glu27 polymorphism may limit beta(2)-adrenoceptor downregulation and predict body mass index (BMI), particularly among sedentary persons. In addition, BMI predicts asthma. We hypothesized that these DNA sequence variants predict adult-onset asthma only in sedentary women. DESIGN: Nested case-control study. SETTING: Nurses' Health Study, a large, prospective cohort study with participants throughout the United States. PARTICIPANTS: Among lifelong nonsmokers, 171 women with adult-onset, medication-requiring asthma and 137 age-matched control subjects. MEASUREMENTS: Physical activity and BMI were self-reported by previously validated questionnaire items. Genomic DNA was obtained from buccal brushings collected via first-class mail. RESULTS: Of 76 sedentary women, the adjusted odds ratios of Gly16 allele were 7.4 (p = 0.047) for asthma and 13.8 (p = 0.02) for steroid-requiring asthma. No similar associations were observed among 232 active women (p = 0.91). Sedentary individuals with both Gly16 and Glu27 alleles had a less elevated risk for asthma. BMI was associated with asthma and Glu27 allele among sedentary women. CONCLUSION: This exploratory analysis suggests an important gene/environment interaction for asthma involving physical activity level. Further study in larger populations is warranted to confirm if sedentary lifestyle unmasks a genetic risk for asthma.


Assuntos
Asma/etiologia , Índice de Massa Corporal , Exercício Físico , Polimorfismo Genético , Receptores Adrenérgicos beta 2/genética , Adulto , Idade de Início , Asma/genética , Feminino , Predisposição Genética para Doença , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Mutação Puntual
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