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3.
RSC Adv ; 13(8): 5081-5095, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36777934

RESUMO

The synthesis and characterization of polydopamine (PDA) using dopamine (DA) as the monomer and (hydroxymethyl)aminomethane (TRIS) as the oxidant is studied. The effect of temperature and TRIS concentration on the kinetics of dopamine polymerization is evaluated, and the kinetic parameters are also calculated. Three TRIS concentrations are used to assess their effect on DA polymerization kinetics. The reaction at 1.5 mmol of TRIS shows a sustained increase of the rate constant with temperature from 2.38 × 10-4 to 5.10 × 10-4 when the temperature is increased from 25 to 55 °C; however, not all reactions follow an Arrhenius law. In addition, the correlation between the synthesis parameters and morphological, structural, and thermal properties of polydopamine is established. The morphology of the PDA particles is evaluated by Scanning Electron Microscopy (SEM), the relationships between the diameter, distribution size, and the rate constant. Thermal characterization by Differential Scanning Calorimetry (DSC) shows an endothermic transition around 130 °C associated with the melting of PDA's regular structure. It is supported by structural studies, such as infrared and Raman spectroscopy and X-ray Diffraction (XRD), by observing a broad peak at 23.1° (2θ) that fits with a graphitic-like structure of PDA.

4.
Neurocirugía (Soc. Luso-Esp. Neurocir.) ; 33(6): 350-355, nov.-dic. 2022. ilus
Artigo em Inglês | IBECS | ID: ibc-212994

RESUMO

Central nervous system (CNS) involvement in the context of relapsed/refractory Hodgkin lymphoma (HL) is a quite rare, but well-known complication. Nevertheless, primary CNS–HL is an exceedingly rare condition, which diagnosis is based on well-defined morphological and immunohistochemical features, in addition to isolated involvement of the CNS. In spite of limited casuistry (just over twenty cases reported in the literature), available data agree that primary and isolated CNS–HL, when treated with a combination of surgery followed by some form of adjuvant therapy (radiotherapy±chemotherapy), carries a better prognosis than those cases with CNS involvement in the context of relapsed/refractory HL or those with CNS non-Hodgkin lymphoma. We herein report a case of a 55-year-old female patient who was diagnosed with primary CNS–HL. The patient was treated with complete surgical resection followed by intrathecal chemotherapy and whole brain radiotherapy (WBRT), showing fourteen months of disease-free survival at the time of this case report. A review of the available literature is also presented (AU)


La afectación del sistema nervioso central (SNC) en pacientes con diagnóstico de linfoma de Hodgkin (LH) sistémico es una complicación muy poco frecuente, aunque bien definida. Sin embargo, el LH primario del SNC es una entidad extremadamente rara, cuyo diagnóstico precisa la identificación de un patrón morfológico e inmunohistoquímico específico, así como la afectación aislada del SNC. Pese a contar con una casuística muy limitada (apenas una veintena de casos publicados en la literatura) la bibliografía disponible coincide en que el LH con afectación primaria y aislada del SNC, cuando es tratado con cirugía y tratamiento adyuvante (radioterapia±quimioterapia), parece tener un mejor pronóstico que aquellos casos en los que la afectación del SNC se produce en el contexto de un LH sistémico o en el contexto de un linfoma no Hodgkin. En este artículo se presenta el caso de una mujer de 55 años con diagnóstico histopatológico de LH primario del SNC. La paciente fue sometida a una exéresis completa de la lesión y a tratamiento adyuvante con quimioterapia intratecal y radioterapia holocraneal, con una supervivencia libre de enfermedad hasta la fecha de 14 meses. Se presenta asimismo, la revisión de la literatura disponible (AU)


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Linfoma não Hodgkin/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Linfoma não Hodgkin/terapia , Neoplasias Encefálicas/terapia , Imageamento por Ressonância Magnética , Intervalo Livre de Doença , Terapia Combinada , Craniotomia
5.
Neurocirugia (Astur : Engl Ed) ; 33(6): 350-355, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36333092

RESUMO

Central nervous system (CNS) involvement in the context of relapsed/refractory Hodgkin lymphoma (HL) is a quite rare, but well-known complication. Nevertheless, primary CNS-HL is an exceedingly rare condition, which diagnosis is based on well-defined morphological and immunohistochemical features, in addition to isolated involvement of the CNS. In spite of limited casuistry (just over twenty cases reported in the literature), available data agree that primary and isolated CNS-HL, when treated with a combination of surgery followed by some form of adjuvant therapy (radiotherapy±chemotherapy), carries a better prognosis than those cases with CNS involvement in the context of relapsed/refractory HL or those with CNS non-Hodgkin lymphoma. We herein report a case of a 55-year-old female patient who was diagnosed with primary CNS-HL. The patient was treated with complete surgical resection followed by intrathecal chemotherapy and whole brain radiotherapy (WBRT), showing fourteen months of disease-free survival at the time of this case report. A review of the available literature is also presented.


Assuntos
Neoplasias do Sistema Nervoso Central , Doença de Hodgkin , Feminino , Humanos , Pessoa de Meia-Idade , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/terapia , Doença de Hodgkin/patologia , Neoplasias do Sistema Nervoso Central/diagnóstico por imagem , Neoplasias do Sistema Nervoso Central/terapia , Intervalo Livre de Doença , Prognóstico , Sistema Nervoso Central
10.
Nature ; 592(7854): 397-402, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33731930

RESUMO

The ocean contains unique biodiversity, provides valuable food resources and is a major sink for anthropogenic carbon. Marine protected areas (MPAs) are an effective tool for restoring ocean biodiversity and ecosystem services1,2, but at present only 2.7% of the ocean is highly protected3. This low level of ocean protection is due largely to conflicts with fisheries and other extractive uses. To address this issue, here we developed a conservation planning framework to prioritize highly protected MPAs in places that would result in multiple benefits today and in the future. We find that a substantial increase in ocean protection could have triple benefits, by protecting biodiversity, boosting the yield of fisheries and securing marine carbon stocks that are at risk from human activities. Our results show that most coastal nations contain priority areas that can contribute substantially to achieving these three objectives of biodiversity protection, food provision and carbon storage. A globally coordinated effort could be nearly twice as efficient as uncoordinated, national-level conservation planning. Our flexible prioritization framework could help to inform both national marine spatial plans4 and global targets for marine conservation, food security and climate action.


Assuntos
Biodiversidade , Clima , Conservação dos Recursos Naturais , Abastecimento de Alimentos , Aquecimento Global/prevenção & controle , Animais , Sequestro de Carbono , Pesqueiros , Sedimentos Geológicos/química , Atividades Humanas , Cooperação Internacional
11.
Sci Adv ; 6(44)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33115738

RESUMO

Contrary to most terrestrial organisms, which release their carbon into the atmosphere after death, carcasses of large marine fish sink and sequester carbon in the deep ocean. Yet, fisheries have extracted a massive amount of this "blue carbon," contributing to additional atmospheric CO2 emissions. Here, we used historical catches and fuel consumption to show that ocean fisheries have released a minimum of 0.73 billion metric tons of CO2 (GtCO2) in the atmosphere since 1950. Globally, 43.5% of the blue carbon extracted by fisheries in the high seas comes from areas that would be economically unprofitable without subsidies. Limiting blue carbon extraction by fisheries, particularly on unprofitable areas, would reduce CO2 emissions by burning less fuel and reactivating a natural carbon pump through the rebuilding of fish stocks and the increase of carcasses deadfall.

12.
Proc Natl Acad Sci U S A ; 117(45): 28134-28139, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33106411

RESUMO

Marine protected areas (MPAs) are conservation tools that are increasingly implemented, with growing national commitments for MPA expansion. Perhaps the greatest challenge to expanded use of MPAs is the perceived trade-off between protection and food production. Since MPAs can benefit both conservation and fisheries in areas experiencing overfishing and since overfishing is common in many coastal nations, we ask how MPAs can be designed specifically to improve fisheries yields. We assembled distribution, life history, and fisheries exploitation data for 1,338 commercially important stocks to derive an optimized network of MPAs globally. We show that strategically expanding the existing global MPA network to protect an additional 5% of the ocean could increase future catch by at least 20% via spillover, generating 9 to 12 million metric tons more food annually than in a business-as-usual world with no additional protection. Our results demonstrate how food provisioning can be a central driver of MPA design, offering a pathway to strategically conserve ocean areas while securing seafood for the future.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Pesqueiros , Segurança Alimentar , Alimentos Marinhos , Animais , Peixes , Humanos
14.
Sci Adv ; 4(8): eaau2161, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30083613

RESUMO

The patterns by which different nations share global fisheries influence outcomes for food security, trajectories of economic development, and competition between industrial and small-scale fishing. We report patterns of industrial fishing effort for vessels flagged to higher- and lower-income nations, in marine areas within and beyond national jurisdiction, using analyses of high-resolution fishing vessel activity data. These analyses reveal global dominance of industrial fishing by wealthy nations. Vessels flagged to higher-income nations, for example, are responsible for 97% of the trackable industrial fishing on the high seas and 78% of such effort within the national waters of lower-income countries. These publicly accessible vessel tracking data have important limitations. However, insights from these new analyses can begin to strategically inform important international- and national-level efforts underway now to ensure equitable and sustainable sharing of fisheries.


Assuntos
Países Desenvolvidos , Pesqueiros/estatística & dados numéricos , Pesqueiros/normas , Animais , Oceanos e Mares
15.
Science ; 361(6404)2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-30139846

RESUMO

Amoroso et al demonstrate the power of our data by estimating the high-resolution trawling footprint on seafloor habitat. Yet we argue that a coarser grid is required to understand full ecosystem impacts. Vessel tracking data allow us to estimate the footprint of human activities across a variety of scales, and the proper scale depends on the specific impact being investigated.


Assuntos
Pesqueiros , Peixes , Animais , Conservação dos Recursos Naturais , Ecossistema , Atividades Humanas , Humanos
17.
Sci Adv ; 4(6): eaat2504, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29881780

RESUMO

While the ecological impacts of fishing the waters beyond national jurisdiction (the "high seas") have been widely studied, the economic rationale is more difficult to ascertain because of scarce data on the costs and revenues of the fleets that fish there. Newly compiled satellite data and machine learning now allow us to track individual fishing vessels on the high seas in near real time. These technological advances help us quantify high-seas fishing effort, costs, and benefits, and assess whether, where, and when high-seas fishing makes economic sense. We characterize the global high-seas fishing fleet and report the economic benefits of fishing the high seas globally, nationally, and at the scale of individual fleets. Our results suggest that fishing at the current scale is enabled by large government subsidies, without which as much as 54% of the present high-seas fishing grounds would be unprofitable at current fishing rates. The patterns of fishing profitability vary widely between countries, types of fishing, and distance to port. Deep-sea bottom trawling often produces net economic benefits only thanks to subsidies, and much fishing by the world's largest fishing fleets would largely be unprofitable without subsidies and low labor costs. These results support recent calls for subsidy and fishery management reforms on the high seas.


Assuntos
Pesqueiros/economia , Modelos Econômicos , Humanos , Oceanografia , Oceanos e Mares , Análise Espacial
18.
Nat Ecol Evol ; 2(4): 650-658, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29572526

RESUMO

Perhaps the greatest challenge facing global fisheries is that recovery often requires substantial short-term reductions in fishing effort, catches and profits. These costs can be onerous and are borne in the present; thus, many countries are unwilling to undertake such socially and politically unpopular actions. We argue that many nations can recover their fisheries while avoiding these short-term costs by sharply addressing illegal, unreported and unregulated (IUU) fishing. This can spur fishery recovery, often at little or no cost to local economies or food provision. Indonesia recently implemented aggressive policies to curtail the high levels of IUU fishing it experiences from foreign-flagged vessels. We show that Indonesia's policies have reduced total fishing effort by at least 25%, illustrating with empirical evidence the possibility of achieving fishery reform without short-term losses to the local fishery economy. Compared with using typical management reforms that would require a 15% reduction in catch and 16% reduction in profit, the approach of curtailing IUU has the potential to generate a 14% increase in catch and a 12% increase in profit. Applying this model globally, we find that addressing IUU fishing could facilitate similar rapid, long-lasting fisheries gains in many regions of the world.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Pesqueiros/legislação & jurisprudência , Regulamentação Governamental , Indonésia
19.
Science ; 359(6378): 904-908, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29472481

RESUMO

Although fishing is one of the most widespread activities by which humans harvest natural resources, its global footprint is poorly understood and has never been directly quantified. We processed 22 billion automatic identification system messages and tracked >70,000 industrial fishing vessels from 2012 to 2016, creating a global dynamic footprint of fishing effort with spatial and temporal resolution two to three orders of magnitude higher than for previous data sets. Our data show that industrial fishing occurs in >55% of ocean area and has a spatial extent more than four times that of agriculture. We find that global patterns of fishing have surprisingly low sensitivity to short-term economic and environmental variation and a strong response to cultural and political events such as holidays and closures.


Assuntos
Pesqueiros/estatística & dados numéricos , Pesqueiros/tendências , Peixes , Animais , Atividades Humanas , Humanos , Oceanos e Mares , Navios , Análise Espaço-Temporal
20.
J Biol Chem ; 291(17): 9343-55, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-26929411

RESUMO

Cytochrome c oxidase assembly requires the synthesis of the mitochondria-encoded core subunits, Cox1, Cox2, and Cox3. In yeast, Pet54 protein is required to activate translation of the COX3 mRNA and to process the aI5ß intron on the COX1 transcript. Here we report a third, novel function of Pet54 on Cox1 synthesis. We observed that Pet54 is necessary to achieve an efficient Cox1 synthesis. Translation of the COX1 mRNA is coupled to the assembly of cytochrome c oxidase by a mechanism that involves Mss51. This protein activates translation of the COX1 mRNA by acting on the COX1 5'-UTR, and, in addition, it interacts with the newly synthesized Cox1 protein in high molecular weight complexes that include the factors Coa3 and Cox14. Deletion of Pet54 decreased Cox1 synthesis, and, in contrast to what is commonly observed for other assembly mutants, double deletion of cox14 or coa3 did not recover Cox1 synthesis. Our results show that Pet54 is a positive regulator of Cox1 synthesis that renders Mss51 competent as a translational activator of the COX1 mRNA and that this role is independent of the assembly feedback regulatory loop of Cox1 synthesis. Pet54 may play a role in Mss51 hemylation/conformational change necessary for translational activity. Moreover, Pet54 physically interacts with the COX1 mRNA, and this binding was independent of the presence of Mss51.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/biossíntese , Proteínas Mitocondriais/biossíntese , Biossíntese de Proteínas/fisiologia , Proteínas de Ligação a RNA/metabolismo , Proteínas de Saccharomyces cerevisiae/biossíntese , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Regiões 5' não Traduzidas/fisiologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas Mitocondriais/genética , RNA Fúngico/genética , RNA Fúngico/metabolismo , Proteínas de Ligação a RNA/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
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