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1.
Sci Total Environ ; 915: 170155, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38228241

RESUMO

Plastic pollution in the Southern Ocean around Antarctica is a growing concern, but many areas in this vast region remain unexplored. This study provides the first comprehensive analysis of marine microplastic (MPs) concentrations in Potter Cove, located near the Argentinian Carlini research station on 25 de Mayo/King George Island, Antarctica. Water samples were collected at 14 sites within the cove, representing various influences from the station's activities. Two sampling methods were used: a 5 L Niskin bottle and an in-situ filtering device called Microfilter, allowing for large water volumes to be filtered. MPs were found in 100 % of the samples. Microfilter samples ranged from 0.02 to 2.14 MPs/L, with a mean concentration of 0.44 ± 0.44 MPs/L. Niskin bottle samples showed concentrations from 0.40 to 55.67 MPs/L, with a mean concentration of 19.03 ± 18.21 MPs/L. The dominant types of MPs were anthropogenic black, transparent, and pink microfibers (MFs) measuring between 0.11 and 3.6 mm (Microfilter) and 0.06 to 7.96 mm (Niskin bottle), with a median length of 0.01 mm for both methods. Transparent and black irregular microfragments (MFRs) with diameters from 0.10 to 5.08 mm and a median diameter of 0.49 mm were also prevalent. FTIR-spectroscopy revealed the presence of 14 types of polymers. Cellulose-based materials and polyethylene terephthalate were the most abundant in MFs, while polyurethanes and styrene-based copolymers dominated in MFRs. MPs were more abundant near the Carlini station. Compared to other coastal Antarctic areas, the MPs in the cove were relatively abundant and mostly smaller than 1 mm. Local activities on the island were identified as the primary source of MPs in the cove, and the cyclonic water circulation likely affects the distribution of small-sized particles. To protect the ecosystem, reducing plastic usage, improving waste management, regulating MPs debris, and enhancing wastewater practices are essential.

2.
Artigo em Inglês | MEDLINE | ID: mdl-35036300

RESUMO

OBJECTIVES: Only few studies evaluated whether hurricane preparedness impacts health. The PREPARE study addresses this gap. METHODS: We recruited participants who had pertinent pre-hurricane data from the San Juan Overweight Adults Longitudinal Study (SOALS: n=364) and 125 patients with diabetes from Federally Qualified Health Center (COSSMA) in Puerto Rico. Participants aged 42-75 years completed interviews 20-34 months after Hurricanes Irma and Maria. We evaluated associations between self-reported hurricane preparedness and health and other related associations using logistic regression controlling for age, location, education and interview date. RESULTS: Only 41% of participants reported high pre-hurricane preparedness; 25% reported gaps (moderate/low availability) in information and 48% reported gaps in resources for hurricane preparedness. Participants reporting lower pre-hurricane preparedness had higher reported hurricane-related detrimental health impact (OR=1.96; 95% CI: 1.31, 2.95) and higher odds (OR=2.07; 95% CI: 0.92, 4.68) of developing new non-communicable disease (NCD) compared to others. Post-hurricane drinking water disruption for ≥ 3 months versus none or less (OR=2.76; 95% CI: 1.39, 5.47) and similarly diet changes due to cooking/refrigeration access (OR=1.96; 95% CI: 1.24, 3.07), and diet changes for ≥ 20 months due to finances/access to shops (OR=2.83; 95% CI: 1.85, 4.32) were also associated with detrimental health impact. CONCLUSION: Lower preparedness was associated with higher detrimental impact of the hurricanes on overall health, and marginally significant impact on NCD. Future preparedness efforts could especially target means of coping with disruption of water services and regular diet, as these were also associated with detrimental health impact.

3.
West Afr J Med ; 38(8): 807-810, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34508330

RESUMO

Antiphospholipid syndrome is a systemic autoimmune disease characterized by thrombosis and/or pregnancy morbidity in the presence of persistently positive antiphospholipid antibodies. The finding of individuals who present a clinical picture highly suggestive of antiphospholipid syndrome, but who are persistently negative for "criteria" of antiphospholipid antibodies has led physicians to refer to this patient population as having "seronegative" Antiphospholipid syndrome. We present a case of a 35-years old patient with strong clinical suspicion of antiphospholipid syndrome, with a history of recurrent pregnancy loss and one episode of deep vein thrombosis, but serologically negative, who was admitted and successfully managed and discharged.


Le syndrome des antiphospholipides est une maladie autoimmune systémique caractérisée par une thrombose et/ou une morbidité de la grossesse en présence d'anticorps antiphospholipides positifs persistants. La découverte d'individus qui présentent un tableau clinique hautement évocateur du syndrome des antiphospholipides, mais qui sont constamment négatifs pour les « critères ¼ des anticorps antiphospholipides a conduit les médecins à qualifier cette population de patients de syndrome des antiphospholipides « séronégatifs ¼. Nous présentons le cas d'une patiente de 35 ans avec une forte suspicion clinique de syndrome des antiphospholipides, avec des antécédents de fausses couches à répétition et un épisode de thrombose veineuse profonde, mais sérologiquement négative, qui a été admise et prise en charge avec succès et sortie de l'hôpital.


Assuntos
Síndrome Antifosfolipídica , Trombose , Adulto , Anticorpos Antifosfolipídeos , Síndrome Antifosfolipídica/diagnóstico , Feminino , Gana , Hospitais de Ensino , Humanos , Gravidez
8.
Acta Neuropathol ; 131(2): 281-298, 2016 02.
Artigo em Inglês | MEDLINE | ID: mdl-26687980

RESUMO

Remyelination in multiple sclerosis (MS) lesions often remains incomplete despite the presence of oligodendrocyte progenitor cells (OPCs). Amongst other factors, successful remyelination depends on the phagocytic clearance of myelin debris. However, the proteins in myelin debris that act as potent and selective inhibitors on OPC differentiation and inhibit CNS remyelination remain unknown. Here, we identify the transmembrane signalling protein EphrinB3 as important mediator of this inhibition, using a protein analytical approach in combination with a primary rodent OPC assay. In the presence of EphrinB3, OPCs fail to differentiate. In a rat model of remyelination, infusion of EphrinB3 inhibits remyelination. In contrast, masking EphrinB3 epitopes using antibodies promotes remyelination. Finally, we identify EphrinB3 in MS lesions and demonstrate that MS lesion extracts inhibit OPC differentiation while antibody-mediated masking of EphrinB3 epitopes promotes it. Our findings suggest that EphrinB3 could be a target for therapies aiming at promoting remyelination in demyelinating disease.


Assuntos
Efrina-B3/metabolismo , Esclerose Múltipla/metabolismo , Bainha de Mielina/metabolismo , Células-Tronco Neurais/metabolismo , Oligodendroglia/metabolismo , Animais , Células Cultivadas , Modelos Animais de Doenças , Efrina-B3/genética , Epitopos/metabolismo , Feminino , Humanos , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos Knockout , Esclerose Múltipla/patologia , Bainha de Mielina/patologia , Regeneração Nervosa/fisiologia , Células-Tronco Neurais/patologia , Neurogênese/fisiologia , Oligodendroglia/patologia , Distribuição Aleatória , Ratos Sprague-Dawley , Receptor EphA4/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-21096816

RESUMO

In this work we study the effects of viscosity variations in thin-layer electrochemical deposition (ECD) under galvanostatic conditions through experimental measurements and theoretical modeling. The theoretical model, written in terms of dimensionless quantities, describes diffusive, migratory and convective ion transport in a fluid under galvanostatic conditions. Experiments reveal that as viscosity increases, convection decreases when the cell resistance remains constant. Our numerical model predicts that as viscosity increases, electroconvection becomes less relevant and concentration and convective fronts slow down. The time scaling of this phenomenon is studied and compared to previously reported low viscosity solution studies.


Assuntos
Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/efeitos da radiação , Galvanoplastia/métodos , Modelos Químicos , Simulação por Computador , Campos Eletromagnéticos , Transporte de Íons/efeitos da radiação , Soluções/química , Soluções/efeitos da radiação , Viscosidade
11.
Ophthalmology ; 105(9): 1775-9, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9754191

RESUMO

OBJECTIVE: Ketorolac tromethamine 0.5% and diclofenac sodium 0.1% ophthalmic solutions are approved for use by the U.S. Food and Drug Administration to avoid excessive postoperative inflammation after cataract surgery and implantation of an intraocular lens. This study compares the efficacy and toxicity of these nonsteroidal anti-inflammatory drugs for the first time. DESIGN: Randomized, double-masked, prospective clinical trial. PARTICIPANTS: A total of 120 patients assigned in equal numbers to 1 of the 2 treatment regimens. INTERVENTION: Treatment with either ketorolac 0.5% or diclofenac 0.1% ophthalmic solutions instilled four times daily for 30 days beginning the first postoperative day after surgery. MAIN OUTCOME MEASURES: Objective (Kowa FC 1000 laser cell and flare meter) and subjective (slit-lamp biomicroscope) measurements of inflammation and toxicity were made and compared at three separate post-operative visits. RESULTS: The anti-inflammatory effects of the two treatment regimens were not statistically different at any of the postoperative visits. Patients tolerated both treatments equally well. CONCLUSIONS: This study shows diclofenac sodium 0.1% and ketorolac tromethamine 0.5% ophthalmic solutions are equally effective and safe for the control of postoperative inflammation after uncomplicated cataract surgery performed by phacoemulsification followed by the implantation of a foldable intraocular lens.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Diclofenaco/administração & dosagem , Facoemulsificação/efeitos adversos , Tolmetino/análogos & derivados , Trometamina/análogos & derivados , Uveíte Anterior/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/efeitos adversos , Diclofenaco/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Inflamação/etiologia , Inflamação/prevenção & controle , Cetorolaco de Trometamina , Implante de Lente Intraocular/efeitos adversos , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas , Estudos Prospectivos , Segurança , Tolmetino/administração & dosagem , Tolmetino/efeitos adversos , Resultado do Tratamento , Trometamina/administração & dosagem , Trometamina/efeitos adversos , Uveíte Anterior/etiologia
13.
Yeast ; 9(12): 1349-54, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8154186

RESUMO

As part of the EEC yeast genome program, a fragment of 15,820 bp from the right arm of Saccharomyces cerevisiae chromosome XI has been sequenced. This fragment corresponds roughly to the centromere-distal half of cosmid pUKG046 and to a small fragment of cosmid pUKG096, which are located approximately 150 kb from the centromere. It contains four open reading frames (ORFs) which encode potential proteins of more than 100 amino acid residues, as well as the UBI2 gene which carries an intron and does not show up as an ORF in the sequence analysis programs. One of the putative proteins, YKR412, is very rich in serine and has significant homology at the carboxyl end to Nopp140 phosphoprotein. YKR413 has several predicted transmembrane domains. YKR15, which has been recently cloned as the MPL1 gene, encodes a polypeptide that shows homologies to myosin heavy chain and to the cytoskeleton protein Uso1.


Assuntos
Genes Fúngicos , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Sequência de Bases , Cromossomos Fúngicos , DNA Fúngico/genética , Proteínas Fúngicas/genética , Humanos , Dados de Sequência Molecular , Miosinas/genética , Fases de Leitura Aberta , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico
15.
Invest Ophthalmol Vis Sci ; 34(10): 2970-5, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8395484

RESUMO

PURPOSE: Agents that increase intracellular levels of cAMP mediate gene expression associated with cellular morphology, growth, and/or differentiation via the cAMP response element (CRE). The cAMP element binding protein (CREB) is a transcriptional activator that binds and stimulates gene expression from the CRE in the promoters of cAMP responsive genes. This study was designed to characterize the cyclic AMP (cAMP) transcription apparatus in bovine corneal endothelial cells (BCE). METHODS: CRE transcriptional activity was determined by transient transfection assays using the CRE-chloramphenicol acetyl transferase gene (CRE-CAT) fusion reporter construct. Western blot analyses were performed to determine whether CREB was present in BCE. Mobility shift DNA-binding assay using gel electrophoresis and DNase I protection assays were performed to exclude the possibility of other CRE-binding factors. RESULTS: The authors identified the transcription factor, CREB, in nuclear extracts from BCE by Western blot analysis and showed that its DNA-binding characteristics are identical to the previously characterized CREB protein by DNase I protection and mobility shift DNA-binding studies. Transient transfection studies using the CRE-CAT reporter constructs revealed that the beta-adrenergic receptor agonist, isoproterenol, stimulates gene expression to levels similar to those induced by forskolin, a direct activator of adenylate cyclase (6.0- and 7.2-fold, respectively). CONCLUSIONS: The results suggest that agents that modulate receptors coupled to adenylate cyclase may effect the corneal endothelium by altering gene expression through the second messenger, cAMP.


Assuntos
AMP Cíclico/metabolismo , Endotélio Corneano/enzimologia , Regulação Enzimológica da Expressão Gênica , Adenilil Ciclases/genética , Adenilil Ciclases/metabolismo , Animais , Western Blotting , Bovinos , Células Cultivadas , Colforsina/farmacologia , AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Eletroforese em Gel de Poliacrilamida , Endotélio Corneano/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Isoproterenol/farmacologia , Transfecção
16.
Mol Cell Biol ; 11(3): 1306-12, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1671708

RESUMO

Cyclic AMP mediates the hormonal stimulation of a number of eukaryotic genes by directing the protein kinase A (PK-A)-dependent phosphorylation of transcription factor CREB. We have previously determined that although phosphorylation at Ser-133 is critical for induction, this site does not appear to participate directly in transactivation. To test the hypothesis that CREB ultimately activates transcription through domains that are distinct from the PK-A site, we constructed a series of CREB mutants and evaluated them by transient assays in F9 teratocarcinoma cells. Remarkably, a glutamine-rich region near the N terminus appeared to be important for PK-A-mediated induction of CREB since removal of this domain caused a marked reduction in CREB activity. A second region consisting of a short acidic motif (DLSSD) C terminal to the PK-A site also appeared to synergize with the phosphorylation motif to permit transcriptional activation. Biochemical experiments with purified recombinant CREB protein further demonstrate that the transactivation domain is more sensitive to trypsin digestion than are the DNA-binding and dimerization domains, suggesting that the activator region may be structured to permit interactions with other proteins in the RNA polymerase II complex.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Regulação da Expressão Gênica , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição/fisiologia , Transcrição Gênica , Sequência de Aminoácidos , Animais , Clonagem Molecular , AMP Cíclico/fisiologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Análise Mutacional de DNA , Técnicas Imunológicas , Técnicas In Vitro , Dados de Sequência Molecular , Proteínas Nucleares/fisiologia , Fragmentos de Peptídeos/metabolismo , Fosforilação , Proteínas Quinases/fisiologia , Ratos , Proteínas Recombinantes , Somatostatina/genética , Relação Estrutura-Atividade
17.
Metabolism ; 39(9 Suppl 2): 6-12, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2169573

RESUMO

Cyclic AMP (cAMP) mediates the hormonal stimulation of numerous cellular processes by regulating the phosphorylation of critical target proteins. In this report, we review current work suggesting that cAMP regulates transcription of eukaryotic genes through the reversible phosphorylation of a target nuclear protein called CREB. As CREB is currently the only transcription factor that is regulated by a well-defined cytoplasmic kinase-kinase-A, these studies may help to elucidate the general mechanisms underlying signal transduction.


Assuntos
AMP Cíclico/fisiologia , Proteínas de Ligação a DNA/fisiologia , Proteínas Nucleares/fisiologia , Transdução de Sinais/fisiologia , Fatores de Transcrição/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Proteínas de Ligação a DNA/genética , Células Eucarióticas/fisiologia , Humanos , Dados de Sequência Molecular , Mutação
18.
Trends Neurosci ; 13(5): 184-8, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-1693237

RESUMO

A large number of neuropeptides and neurotransmitters stimulate neuronal cells through the second messenger cAMP. These synaptic signals often cause profound changes in neuronal function by altering basic patterns of gene expression. Cyclic AMP, in turn, regulates a number of these genes through a conserved cAMP response element (CRE). Recently, a nuclear CRE-binding protein, CREB, has been shown to bind to the CRE and stimulate the transcription of cAMP-responsive genes. This article reviews recent progress towards understanding the mechanism by which cAMP modulates the activity of CREB to stimulate gene transcription.


Assuntos
AMP Cíclico/fisiologia , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Sistemas do Segundo Mensageiro , Animais , Sequência de Bases , AMP Cíclico/farmacologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Proteínas de Ligação a DNA/fisiologia , Dados de Sequência Molecular , Transcrição Gênica
19.
Cell ; 60(4): 611-7, 1990 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-2137373

RESUMO

In this paper, we characterize a trans-activating region in CREB, termed alpha, that interacts cooperatively with the kinase A phosphorylation motif to stimulate transcription. The alpha region appears to be encoded by an alternate exon that is deleted in a CREB-related cDNA named delta CREB. Both proteins are expressed in eukaryotic cells, although the activity of CREB is 10-fold higher than that of delta CREB. Circular dichroism data on a synthetic "alpha peptide" combined with results from in vitro mutagenesis experiments support the hypothesis that the alpha region contains an amphipathic alpha helix whose structure is critical to CREB activity. We propose that phosphorylation by kinase A may stimulate CREB activity in part by modulating the structure of alpha and thus may stimulate its ability to interact with other proteins in the polymerase II complex.


Assuntos
Proteínas de Ligação a DNA/genética , Transativadores/genética , Fatores de Transcrição/genética , Neoplasias das Glândulas Suprarrenais , Sequência de Aminoácidos , Animais , Sequência de Bases , Encéfalo/metabolismo , Linhagem Celular , Clonagem Molecular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , DNA/metabolismo , Proteínas de Ligação a DNA/isolamento & purificação , Proteínas de Ligação a DNA/metabolismo , Substâncias Macromoleculares , Dados de Sequência Molecular , Feocromocitoma , Plasmídeos , Conformação Proteica , Ratos , Transfecção
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