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1.
Rev Fish Biol Fish ; 32(1): 101-121, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34092936

RESUMO

Food from the sea can make a larger contribution to healthy and sustainable diets, and to addressing hunger and malnutrition, through improvements in production, distribution and equitable access to wild harvest and mariculture resources and products. The supply and consumption of seafood is influenced by a range of 'drivers' including ecosystem change and ocean regulation, the influence of corporations and evolving consumer demand, as well as the growing focus on the importance of seafood for meeting nutritional needs. These drivers need to be examined in a holistic way to develop an informed understanding of the needs, potential impacts and solutions that align seafood production and consumption with relevant 2030 Sustainable Development Goals (SDGs). This paper uses an evidence-based narrative approach to examine how the anticipated global trends for seafood might be experienced by people in different social, geographical and economic situations over the next ten years. Key drivers influencing seafood within the global food system are identified and used to construct a future scenario based on our current trajectory (Business-as-usual 2030). Descriptive pathways and actions are then presented for a more sustainable future scenario that strives towards achieving the SDGs as far as technically possible (More sustainable 2030). Prioritising actions that not only sustainably produce more seafood, but consider aspects of access and utilisation, particularly for people affected by food insecurity and malnutrition, is an essential part of designing sustainable and secure future seafood systems. Supplementary Information: The online version contains supplementary material available at 10.1007/s11160-021-09663-x.

2.
Int J Nanomedicine ; 11: 3731-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27563240

RESUMO

Nosocomial diseases are mainly caused by two common pathogens, Escherichia coli and Staphylococcus aureus, which are becoming more and more resistant to conventional antibiotics. Therefore, it is becoming increasingly necessary to find other alternative treatments than commonly utilized drugs. A promising strategy is to use nanomaterials such as selenium nanoparticles. However, the ability to produce nanoparticles free of any contamination is very challenging, especially for nano-medical applications. This paper reports the successful synthesis of pure selenium nanoparticles by laser ablation in water and determines the minimal concentration required for ~50% inhibition of either E. coli or S. aureus after 24 hours to be at least ~50 ppm. Total inhibition of E. coli and S. aureus is expected to occur at 107±12 and 79±4 ppm, respectively. In this manner, this study reports for the first time an easy synthesis process for creating pure selenium to inhibit bacterial growth.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Nanopartículas , Selênio/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Lasers , Testes de Sensibilidade Microbiana , Nanopartículas/química , Selênio/química , Água/química
3.
Dalton Trans ; 41(48): 14547-56, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23080218

RESUMO

The interaction of trivalent lanthanide and actinide cations with polyaminopolycarboxylic acid complexing agents in lactic acid buffer systems is an important feature of the chemistry of the TALSPEAK process for the separation of trivalent actinides from lanthanides. To improve understanding of metal ion coordination chemistry in this process, the results of an investigation of the kinetics of lanthanide complexation by ethylenediamine-N,N,N',N'-tetraacetic acid (EDTA) and diethylenetriamine-N,N,N',N'',N''-pentaacetic acid (DTPA) in 0.3 M lactic acid/0.3 M ionic strength solution are reported. Progress of the reaction was monitored using the distinctive visible spectral changes attendant to lanthanide complexation by the colorimetric indicator ligand Arsenazo III, which enables the experiment but plays no mechanistic role. Under the conditions of these experiments, the reactions occur in a time regime suitable for study by stopped-flow spectrophotometric techniques. Experiments have been conducted as a function of EDTA/DTPA ligand concentration, total lactic acid concentration, and pH. The equilibrium perturbation reaction proceeds as a first order approach to equilibrium over a wide range of conditions, allowing the simultaneous determination of complex formation and dissociation rate constants. The rate of the complexation reaction has been determined for the entire lanthanide series (except Pm(3+)). The predominant pathway for lanthanide-EDTA and lanthanide-DTPA dissociation is inversely dependent on the total lactate concentration; the complex formation reaction demonstrates a direct dependence on [H(+)]. Unexpectedly, the rate of the complex formation reaction is seen in both ligand systems to be fastest for Gd(3+). Correlation of these results indicates that in 0.3 M lactate solutions the exchange of lanthanide ions between lactate complexes and the polyaminopolycarboxylate govern the process.

6.
Am J Transplant ; 8(1): 162-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17973959

RESUMO

Biliary cirrhosis complicates some adults with cystic fibrosis (CF) and may require transplantation. Cardio-respiratory disease severity varies such that patients may require liver transplantation, heart/lung/liver (triple) grafts or may be too ill for any procedure. A 15-year experience of adults with CF-related liver disease referred for liver transplantation is presented with patient survival as outcome. Twelve patients were listed for triple grafting. Four died of respiratory disease after prolonged waits (4-171 weeks). Eight underwent transplantation (median wait 62 weeks); 5-year actuarial survival was 37.5%. Four died perioperatively; only one is alive at 8-years. Eighteen patients underwent liver transplant alone (median wait 7 weeks); 1- and 5-year actuarial survival rates were 100% and 69%. Three long-term survivors required further organ replacement (two heart/lung and one renal). Two others were turned down for heart/lung transplantation and four have significant renal impairment. Results for triple grafting were poor with unacceptable waiting times. Results for liver transplant alone were satisfactory, with acceptable waiting times and survival. However, further grafts were required and renal impairment was frequent. The policy of early liver transplantation for adults with CF with a view to subsequent heart/lung or renal transplantation needs assessment in the context of long-term outcome.


Assuntos
Fibrose Cística/cirurgia , Hepatopatias/cirurgia , Transplante de Fígado , Adulto , Fibrose Cística/complicações , Fibrose Cística/mortalidade , Feminino , Humanos , Hepatopatias/mortalidade , Transplante de Fígado/mortalidade , Masculino , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Estudos Retrospectivos , Análise de Sobrevida , Sobreviventes
7.
J Cyst Fibros ; 7(3): 252-7, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18042441

RESUMO

BACKGROUND: Liver disease is an important cause of death in adults with cystic fibrosis (CF). Ursodeoxycholic acid (UDCA) may slow progression. Managing varices and timely evaluation for liver transplantation are important. METHODS: Adults with CF underwent annual review. Abnormalities of liver function tests or ultrasound prompted referral to the CF/liver clinic where UDCA was commenced. Endoscopic surveillance for varices was undertaken if ultrasound suggested portal hypertension. RESULTS: 154 patients were followed for a median 5 years. 43 had significant liver disease, 29 had cirrhosis with portal hypertension and 14 had ultrasound evidence of cirrhosis without portal hypertension. All started UDCA. Only one patient developed chronic liver failure and none required liver transplantation. 27 underwent endoscopy; 1 required variceal banding, the others had insignificant varices. Ultrasound was normal in 97 patients while five had steatosis; nine further patients had splenomegaly but no other evidence of portal hypertension. Neither spleen size nor platelet count correlated with portal hypertension. CONCLUSIONS: Liver disease was common in adults with CF but disease progression was rare. Thus liver disease detected and closely monitored in adults appeared to have a milder course than childhood CF. Splenomegaly, unrelated to portal hypertension may be a consequence of CF.


Assuntos
Colagogos e Coleréticos/uso terapêutico , Fibrose Cística/epidemiologia , Hepatopatias/epidemiologia , Ácido Ursodesoxicólico/uso terapêutico , Adulto , Comorbidade , Feminino , Humanos , Hipertensão Portal/epidemiologia , Cirrose Hepática/epidemiologia , Hepatopatias/cirurgia , Transplante de Fígado , Masculino , Contagem de Plaquetas , Estudos Prospectivos , Esplenomegalia , Trombocitopenia/epidemiologia
8.
Transpl Infect Dis ; 10(4): 272-5, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17868274

RESUMO

The management of patients with pre-existing tuberculosis (TB) undergoing liver transplantation is challenging. Cautious immunosuppression is required to prevent reactivation of disease, and second-line anti-tuberculous treatment may be necessary to prevent graft hepatotoxicity. Furthermore, liver transplantation in the context of isoniazid-resistant TB has seldom been reported. We report on a 44-year-old man with recent isoniazid-resistant extra-pulmonary TB who developed subacute hepatic failure requiring emergency liver transplantation and treatment with second-line anti-tuberculous therapy. We demonstrate that patients who have pre-existing TB can be successfully treated with alternative anti-tuberculous medication while under immunosuppression post transplantation. Pre-existing TB, including resistant strains, should not be an absolute contraindication to liver transplantation.


Assuntos
Antituberculosos/efeitos adversos , Farmacorresistência Bacteriana , Isoniazida/efeitos adversos , Falência Hepática Aguda/cirurgia , Transplante de Fígado , Tuberculose dos Linfonodos/tratamento farmacológico , Adulto , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Humanos , Isoniazida/farmacologia , Isoniazida/uso terapêutico , Falência Hepática Aguda/induzido quimicamente , Masculino , Mycobacterium tuberculosis/efeitos dos fármacos , Resultado do Tratamento , Tuberculose dos Linfonodos/microbiologia
9.
J Viral Hepat ; 12(4): 346-56, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15985004

RESUMO

Chronic hepatitis B virus (HBV) infection is an important cause of cirrhosis and hepatocellular carcinoma. Current treatments are limited and may be ineffective. Nucleic acid-mediated targeting of viral mRNA is an attractive and specific approach for viral infection and lentiviral vectors provide a means to express antisense sequences or ribozymes stably in target cells permitting continuous production within that cell and its progeny. To demonstrate long-term gene expression by lentiviral vectors in hepatocytes and to introduce lentiviral vectors expressing anti-HBV genes to assess their effect against HBV, lentiviral vectors expressing a reporter gene were assessed for longevity of gene expression in hepatocytes in vitro. Hammerhead ribozymes and antisense sequences targeting the HBV encapsidation signal (epsilon), X or surface antigen on mRNAs were cloned into lentiviral vectors and used to transduce HBV expressing hepatocytes where the effect on HBV mRNA level was assessed using ribonuclease protection. Gene expression in hepatocytes from integrated vectors continued for over 4 months without selection. Antisense RNA targeting HBs mRNA reduced this transcript, whilst antisense RNA to HBX mRNA was ineffective. Sense RNAs corresponding to epsilon and HBX mRNA also reduced HBV mRNA levels. Ribozymes targeting HBs and HBX mRNA effectively reduced HBV mRNA levels compared with inactive constructs indicating their effect to be enzymatic rather than antisense. Lentiviral vectors can produce long-term gene expression in hepatocytes and thus permit prolonged expression of antiviral genes targeting the HBV encapsidation signal, surface and X mRNAs as treatments for chronic HBV infection.


Assuntos
Vetores Genéticos , Vírus da Hepatite B/genética , Hepatócitos/virologia , RNA Antissenso/genética , RNA Catalítico/genética , RNA Viral/antagonistas & inibidores , Sequência de Bases , Linhagem Celular , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/crescimento & desenvolvimento , Humanos , Lentivirus/genética , Dados de Sequência Molecular , RNA Antissenso/uso terapêutico , RNA Catalítico/uso terapêutico , RNA Mensageiro/antagonistas & inibidores , Transativadores/genética , Proteínas Virais Reguladoras e Acessórias
10.
Dalton Trans ; (11): 2011-6, 2005 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-15909052

RESUMO

The kinetics of the reaction between dioxouranium(VI) and benzene-1,2-diphosphonic acid (BzDPA) has been investigated by stopped-flow spectrophotometry. The rate of reaction of uranyl ions with Arsenazo III (2,7-bis(2,2'-arsonophenylazo)-1,8-dihydroxynaphthalene-3,6-disulfonic acid) in 50:50 methanol-water solutions was also determined. Both formation and dissociation rate constants for the 1:1 complex between uranyl-BzDPA in acidic solutions were resolved. To gain insight into the effect of solvation on the progress of the reaction, the system was studied in triply distilled water, in 50:50 methanol-water, 80:20 methanol-water and in 50:50 tert-butanol-water as a function of temperature at pH 1.0. The rates of complex formation and dissociation reactions decrease as methanol substitutes for water in the medium and further decrease as tert-butanol replaces methanol as co-solvent. Activation parameters are most consistent with an associative process governing the progress of both complex formation and dissociation reactions. Introduction of alcoholic co-solvents results in notably more negative activation entropies for both complex formation and dissociation reactions, while the activation enthalpies are only slightly reduced in the mixed methanol-water medium. These results are compared with the kinetic features of other U(VI) systems.

12.
Nucl Med Biol ; 28(4): 419-24, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11395315

RESUMO

The new bisphosphonate ligand SEDP (2-sulfonato-1,1-ethylidene bisphosphonic acid) has been synthesized and characterized, including the determination of the protonation constants, and used to form (188)Re-(Sn)SEDP from Na(188)ReO4. The title compound (188)Re-(Sn)SEDP shows slightly greater bone uptake and less kidney uptake than (188)Re-(Sn)HEDP in rat biodistribution studies.


Assuntos
Osso e Ossos/diagnóstico por imagem , Organofosfonatos/síntese química , Compostos Radiofarmacêuticos/síntese química , Animais , Difosfonatos , Feminino , Concentração de Íons de Hidrogênio , Ligantes , Espectroscopia de Ressonância Magnética , Cintilografia , Compostos Radiofarmacêuticos/farmacocinética , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
13.
Int J Clin Pract ; 51(6): 384-5, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9489068

RESUMO

The underlying cause of heart failure should be established, where possible. In particular the failure to respond to diuretic and vasodilator therapy requires careful evaluation.


Assuntos
Amiloidose/complicações , Captopril/uso terapêutico , Cardiomiopatias/complicações , Idoso , Cardiomiopatias/tratamento farmacológico , Diuréticos/uso terapêutico , Evolução Fatal , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/etiologia , Humanos , Masculino
15.
Science ; 222(4630): 1323-5, 1983 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-17773333

RESUMO

The solubility of plutonium in Mono Lake water is enhanced by the presence of large concentrations of indigenous carbonate ions and moderate concentrations of fluoride ions. In spite of the complex chemical composition of this water, only a few ions govern the behavior of plutonium, as demonstrated by the fact that it was possible to duplicate plutonium speciation in a synthetic water containing only the principal components of Mono Lake water.

16.
Science ; 221(4607): 271-3, 1983 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-17815196

RESUMO

Neptunium and americium are relatively insoluble in ground waters containing high sulfate concentrations, particularly at 90 degrees C. The insoluble neptunium species is Np(IV); hence reducing waters should enhance its formation. Americium can exist only in the trivalent state under these conditions, and its solubility also should be representative of that of curium.

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