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1.
Ophthalmologe ; 118(4): 337-344, 2021 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-32638094

RESUMO

The Sicca-Förderpreis (Dry Eye Award) supports the development of scientific research on the pathogenesis, diagnostics, and treatment of dry eye and ocular surface diseases. It is awarded after a limited call for proposals in German-speaking countries, written application and selection of the award winner after evaluation by a jury of ophthalmologists working in basic and clinical science. In this article examples of the results of funded projects of the Sicca-Förderpreis 2016 are cursorily described, which were presented at the Ophthalmological Academy of Germany 2019 (Augenärztliche Akademie Deutschland 2019) and therefore provide an insight into current scientific developments. The role of muscarinic receptors and those of urea in the pathogenesis of dry eye as well as the (missing) correlation of tear film stability, viscosity and surface tension are highlighted. A project on the early detection of ocular involvement in graft versus host disease and the idea of treating meibomian gland dysfunction with eyelid surgery techniques are also groundbreaking. The outlined projects represent the potential for further substantial developments in the understanding, diagnostics and treatment of dry eye; however, their long-term clinical relevance still needs to be established.


Assuntos
Distinções e Prêmios , Síndromes do Olho Seco , Doenças Palpebrais , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/terapia , Alemanha , Humanos , Glândulas Tarsais , Lágrimas
2.
Sci Adv ; 6(9): eaaz3801, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32133409

RESUMO

Illegal, unreported, and unregulated fishing is widespread; it is therefore likely that illicit trade in marine fish catch is also common worldwide. We combine ecological-economic databases to estimate the magnitude of illicit trade in marine fish catch and its impacts on people. Globally, between 8 and 14 million metric tons of unreported catches are potentially traded illicitly yearly, suggesting gross revenues of US$9 to US$17 billion associated with these catches. Estimated loss in annual economic impact due to the diversion of fish from the legitimate trade system is US$26 to US$50 billion, while losses to countries' tax revenues are between US$2 and US$4 billion. Country-by-country estimates of these losses are provided in the Supplementary Materials. We find substantial likely economic effects of illicit trade in marine fish catch, suggesting that bold policies and actions by both public and private actors are needed to curb this illicit trade.


Assuntos
Conservação dos Recursos Naturais/economia , Ecossistema , Pesqueiros/economia , Peixes , Modelos Biológicos , Modelos Econômicos , Animais , Humanos
3.
J Appl Microbiol ; 123(5): 1168-1183, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28853204

RESUMO

AIMS: The work aimed at developing and evaluating practically relevant methods for testing of disinfectants on contaminated personal protective equipment (PPE). METHODS AND RESULTS: Carriers were prepared from PPE fabrics and contaminated with Bacillus subtilis spores. Peracetic acid (PAA) was applied as a suitable disinfectant. In method 1, the contaminated carrier was submerged in PAA solution; in method 2, the contaminated area was covered with PAA; and in method 3, PAA, preferentially combined with a surfactant, was dispersed as a thin layer. In each method, 0·5-1% PAA reduced the viability of spores by a factor of ≥6 log10 within 3 min. The technique of the most realistic method 3 proved to be effective at low temperatures and also with a high organic load. Vaccinia virus and Adenovirus were inactivated with 0·05-0·1% PAA by up to ≥6 log10 within 1 min. The cytotoxicity of ricin was considerably reduced by 2% PAA within 15 min of exposure. CONCLUSIONS: PAA/detergent mixture enabled to cover hydrophobic PPE surfaces with a thin and yet effective disinfectant layer. SIGNIFICANCE AND IMPACT OF THE STUDY: The test methods are objective tools for estimating the biocidal efficacy of disinfectants on hydrophobic flexible surfaces.


Assuntos
Desinfetantes/farmacologia , Desinfecção/métodos , Ácido Peracético/farmacologia , Equipamento de Proteção Individual/microbiologia , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/crescimento & desenvolvimento , Desinfecção/instrumentação
4.
Analyst ; 138(20): 6154-62, 2013 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-23971072

RESUMO

This article describes a novel bioluminescence assay for detecting the proteolytic activity of Botulinum NeuroToxins (BoNT) in complex matrices. The assay is capable of detecting traces of BoNT in blood samples as well as in food drinks. The assay was responsive to BoNT/A subtypes 1 to 5, and serotype E3 in buffered solutions. It was responsive to filtered Clostridium botulinum supernatants and BoNT/A1 in complex with neurotoxin associated proteins in bouillon and milk (3.8% fat) down to 400 fM after 4 h RT incubation and in bouillon at concentrations down to 120 fM after 21 h RT incubation. In combination with an immunocapture/enrichment step it could detect BoNT/A1 in citrated plasma at concentrations down to 30 fM (1.2 mouse LD50 per mL). The simplicity of the assay, combined with a demonstrated ability to lyophilize the reagents, demonstrates its usefulness for detection of BoNT in non-specialised analytical laboratories.


Assuntos
Toxinas Botulínicas Tipo A/análise , Toxinas Botulínicas Tipo A/química , Medições Luminescentes/métodos , Animais , Clostridium botulinum/química , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Secundária de Proteína
5.
Am J Transplant ; 13(5): 1203-16, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23433101

RESUMO

In an open-label, 24-month trial, 721 de novo heart transplant recipients were randomized to everolimus 1.5 mg or 3.0 mg with reduced-dose cyclosporine, or mycophenolate mofetil (MMF) 3 g/day with standard-dose cyclosporine (plus corticosteroids ± induction). Primary efficacy endpoint was the 12-month composite incidence of biopsy-proven acute rejection, acute rejection associated with hemodynamic compromise, graft loss/retransplant, death or loss to follow-up. Everolimus 1.5 mg was noninferior to MMF for this endpoint at month 12 (35.1% vs. 33.6%; difference 1.5% [97.5% CI: -7.5%, 10.6%]) and month 24. Mortality to month 3 was higher with everolimus 1.5 mg versus MMF in patients receiving rabbit antithymocyte globulin (rATG) induction, mainly due to infection, but 24-month mortality was similar (everolimus 1.5 mg 10.6% [30/282], MMF 9.2% [25/271]). Everolimus 3.0 mg was terminated prematurely due to higher mortality. The mean (SD) 12-month increase in maximal intimal thickness was 0.03 (0.05) mm with everolimus 1.5 mg versus 0.07 (0.11) mm with MMF (p < 0.001). Everolimus 1.5 mg was inferior to MMF for renal function but comparable in patients achieving predefined reduced cyclosporine trough concentrations. Nonfatal serious adverse events were more frequent with everolimus 1.5 mg versus MMF. Everolimus 1.5 mg with reduced-dose cyclosporine offers similar efficacy to MMF with standard-dose cyclosporine and reduces intimal proliferation at 12 months in de novo heart transplant recipients.


Assuntos
Rejeição de Enxerto/tratamento farmacológico , Transplante de Coração , Ácido Micofenólico/análogos & derivados , Sirolimo/análogos & derivados , Doença Aguda , Anti-Inflamatórios não Esteroides , Antineoplásicos , Ásia/epidemiologia , Austrália/epidemiologia , Biópsia , Relação Dose-Resposta a Droga , Europa (Continente)/epidemiologia , Everolimo , Feminino , Seguimentos , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/epidemiologia , Humanos , Imunossupressores/administração & dosagem , Incidência , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/administração & dosagem , Miocárdio/patologia , América do Norte/epidemiologia , Estudos Prospectivos , Sirolimo/administração & dosagem , América do Sul/epidemiologia , Resultado do Tratamento , Ultrassonografia de Intervenção
6.
J Fish Biol ; 80(5): 1643-77, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22497402

RESUMO

In this review, shark-fin-to-body-mass ratios, which have been legislated by several countries as a means of regulating and monitoring shark fisheries, have been compiled and reviewed. Observed and legislated wet-fin-mass-to-round-mass (M(fw) :M(r) ) ratios have been collected for 50 species and eight countries. Wet to dry-fin mass conversion factors have also been reviewed. Existing shark fishery legislation was compiled by political entity and regional fishery management organizations (RFMO). The mean observed M(fw) :M(r) ratio for all species was 3·0%, but actual fin to body-mass ratios varied considerably by species and location. Species-specific mean ratios ranged from 1·1 to 10·9%, and estimated mean ratios ranged from 1·5 to 6·1% by country, depending on fin-cutting practices and the mix of exploited species. The mean conversion factor for wet to dry-fin mass was 0·43. Shark-related legislation was found to exist in 37 countries and the 22 maritime members of the European Union, and shark-related regulations have been designated by nine RFMOs. Results suggest that currently regulated ratios may not be appropriate for all species and fin-cutting practices, and regulations based on generalized ratios for all sharks may be inadequate. Alternative policies may be necessary for the effective management of global shark fisheries.


Assuntos
Nadadeiras de Animais , Conservação dos Recursos Naturais/legislação & jurisprudência , Pesqueiros/legislação & jurisprudência , Tubarões/fisiologia , Animais , Tamanho Corporal
7.
Poult Sci ; 88(2): 281-90, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19151341

RESUMO

One of the key benefits in using chickens for immunization is the high yield of antibodies obtainable. It is known that egg production decreases over time, while animal maintenance costs remain stable. It would, however, be desirable to keep hens as long as possible to obtain maximal amounts of antibodies. To identify a suitable length of time that animals can be kept and to optimize the cost:yield ratio, we monitored the number of eggs laid, the total amount of chicken IgY, and the specific antibody titer from individually prepared eggs over a 2-yr period. The plant toxin ricin and the Clostridium botulinum neurotoxins type A and B were used to immunize 4 chickens. The number of eggs laid in 2 yr was approximately 600 per hen (about 80% of the maximum egg number), yielding about 20 to 40 g of total IgY per hen. A stable antibody titer of 1:100,000 to 1:1,000,000, as measured by ELISA, was obtained following up to 11 injections of 10 to 20 microg of immobilized native toxin. Laying capacities were found to decrease, on average, from 7 eggs/wk at the point of first immunization to 2 eggs/wk after more than 2 yr. In parallel, the yield of total and specific IgY increased over time, so that the antibody recovery remained high, even after prolonged immunization times. Using purified IgY preparations, classical immunological assays such as ELISA and Western blotting were performed. Furthermore, the IgY showed neutralizing capacity when used to block the functional activity of the toxins both in vitro and in vivo. Analysis of the total IgY content over time demonstrated a complex biological oscillation (and the antigen-specific titer), with a shorter time period of around 7 d (circaseptan rhythm). In summary, we successfully immunized chickens with ricin and botulinum neurotoxins and monitored laying capacity, IgY concentration, and specific antibody titer over an extended period of 2 yr.


Assuntos
Galinhas/fisiologia , Ovos/análise , Imunoglobulinas/análise , Imunotoxinas/sangue , Oviposição/imunologia , Animais , Toxinas Botulínicas/imunologia , Galinhas/imunologia , Feminino , Imunização/veterinária , Ricina/imunologia
8.
Pharmacogenomics J ; 6(3): 174-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16402084

RESUMO

Two common polymorphisms in the beta1-adrenergic receptor gene, Ser49Gly and Arg389Gly, are associated with variable antihypertensive response to metoprolol. We sought to determine whether similar pharmacogenetic associations were present with the negative chronotropic response phenotype to metoprolol. Metoprolol was titrated in 54 untreated hypertensive patients to achieve blood pressure control. We found no association between either resting or exercise heart rate at baseline (untreated) or in response to metoprolol by codon 389 genotype. In contrast, when compared by codon 49 genotype, Ser49 homozygotes had significantly higher resting heart rates at baseline (untreated) than Gly49 carriers (82+/-10 versus 74+/-11 bpm, respectively, P=0.016). When corrected for plasma concentration, we found no difference in reduction in exercise heart rate in response to metoprolol between Ser49 homozygotes and Gly49 carriers (0.75+/-0.11 versus 0.57+/-0.17%/ng/ml, respectively, P=0.37). However, if one fails to account for plasma concentration, trends toward a significant difference in heart rate reduction are seen between Ser49 homozygotes and Gly49 carriers (31% reduction versus 25% reduction, P=0.05). Our data suggest that neither the beta1-adrenergic receptor Arg389Gly, nor the Ser49Gly polymorphisms are associated with variable negative chronotropic response to metoprolol. In addition, our data highlight the importance of measuring metoprolol concentration in order to account for variable pharmacokinetics and avoid misinterpretation of the data.


Assuntos
Antagonistas Adrenérgicos beta/farmacocinética , Anti-Hipertensivos/farmacocinética , Metoprolol/farmacocinética , Farmacogenética , Alelos , Exercício Físico , Frequência do Gene , Triagem de Portadores Genéticos , Frequência Cardíaca/genética , Homozigoto , Humanos , Fenótipo
9.
Am J Transplant ; 6(1): 150-60, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16433769

RESUMO

Rejection diagnosis by endomyocardial biopsy (EMB) is invasive, expensive and variable. We investigated gene expression profiling of peripheral blood mononuclear cells (PBMC) to discriminate ISHLT grade 0 rejection (quiescence) from moderate/severe rejection (ISHLT > or = 3A). Patients were followed prospectively with blood sampling at post-transplant visits. Biopsies were graded by ISHLT criteria locally and by three independent pathologists blinded to clinical data. Known alloimmune pathways and leukocyte microarrays identified 252 candidate genes for which real-time PCR assays were developed. An 11 gene real-time PCR test was derived from a training set (n = 145 samples, 107 patients) using linear discriminant analysis (LDA), converted into a score (0-40), and validated prospectively in an independent set (n = 63 samples, 63 patients). The test distinguished biopsy-defined moderate/severe rejection from quiescence (p = 0.0018) in the validation set, and had agreement of 84% (95% CI 66% C94%) with grade ISHLT > or = 3A rejection. Patients >1 year post-transplant with scores below 30 (approximately 68% of the study population) are very unlikely to have grade > or = 3A rejection (NPV = 99.6%). Gene expression testing can detect absence of moderate/severe rejection, thus avoiding biopsy in certain clinical settings. Additional clinical experience is needed to establish the role of molecular testing for clinical event prediction and immunosuppression management.


Assuntos
Perfilação da Expressão Gênica , Rejeição de Enxerto/diagnóstico , Transplante de Coração , Adolescente , Adulto , Idoso , Feminino , Rejeição de Enxerto/genética , Rejeição de Enxerto/patologia , Transplante de Coração/imunologia , Humanos , Terapia de Imunossupressão , Leucócitos Mononucleares/química , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise
10.
Med Hypotheses ; 60(2): 149-51, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12606226

RESUMO

Cardiovascular disease still ranks as the leading cause of death in men and women. Adults have tried to lower their risk of cardiovascular disease by improving their diet, quitting smoking, controlling blood pressure and exercising regularly. Additionally, many adults have turned to nutriceutical or natural products. Myocardial ischemia, produces a depression in myocardial tissue levels of high energy compounds, along with a compromise in myocardial function. Ribose, a naturally occurring sugar, has been extensively investigated, both in animal and clinical studies, as an agent to enhance the recovery of these depressed energy compounds. Results of these studies have been promising in enhancing the recovery of these energy molecules along with an improvement in myocardial function. Therefore, ribose should be considered as a potential agent in the treatment of ischemic cardiovascular disease.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Ribose/uso terapêutico , Animais , Humanos , Miocárdio/metabolismo
11.
Nature ; 414(6863): 534-6, 2001 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-11734851

RESUMO

Over 75% of the world marine fisheries catch (over 80 million tonnes per year) is sold on international markets, in contrast to other food commodities (such as rice). At present, only one institution, the Food and Agriculture Organization of the United Nations (FAO) maintains global fisheries statistics. As an intergovernmental organization, however, FAO must generally rely on the statistics provided by member countries, even if it is doubtful that these correspond to reality. Here we show that misreporting by countries with large fisheries, combined with the large and widely fluctuating catch of species such as the Peruvian anchoveta, can cause globally spurious trends. Such trends influence unwise investment decisions by firms in the fishing sector and by banks, and prevent the effective management of international fisheries.


Assuntos
Agricultura/estatística & dados numéricos , Peixes , Animais , China , Conservação dos Recursos Naturais , Pesqueiros/estatística & dados numéricos , Cooperação Internacional , Nações Unidas
12.
Hum Gene Ther ; 12(5): 527-38, 2001 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-11268285

RESUMO

Pompe disease is a lethal cardioskeletal myopathy in infants and results from genetic deficiency of the lysosomal enzyme acid alpha-glucosidase (GAA). Genetic replacement of the cDNA for human GAA (hGAA) is one potential therapeutic approach. Three months after a single intramuscular injection of 10(8) plaque-forming units (PFU) of E1-deleted adenovirus encoding human GAA (Ad-hGAA), the activity in whole muscle lysates of immunodeficient mice is increased to 20 times the native level. Direct transduction of a target muscle, however, may not correct all deficient cells. Therefore, the amount of enzyme that can be transferred to deficient cells from virally transduced cells was studied. Fibroblasts from an affected patient were transduced with AdhGAA, washed, and plated on transwell culture dishes to serve as donors of recombinant enzyme. Deficient fibroblasts were plated as acceptor cells, and were separated from the donor monolayer by a 22-microm pore size filter. Enzymatic and Western analyses demonstrate secretion of the 110-kDa precursor form of hGAA from the donor cells into the culture medium. This recombinant, 110-kDa species reaches the acceptor cells, where it can be taken up by mannose 6-phosphate receptor-mediated endocytosis. It then trafficks to lysosomes, where Western analysis shows proteolytic processing to the 76- and 70-kDa lysosomal forms of the enzyme. Patient fibroblasts receiving recombinant hGAA by this transfer mechanism reach levels of enzyme activity that are comparable to normal human fibroblasts. Skeletal muscle cell cultures from an affected patient were also transduced with Ad-hGAA. Recombinant hGAA is identified in a lysosomal location in these muscle cells by immunocytochemistry, and enzyme activity is transferred to deficient skeletal muscle cells grown in coculture. Transfer of the precursor protein between muscle cells again occurs via mannose 6-phosphate receptors, as evidenced by competitive inhibition with 5 mM mannose 6-phosphate. In vivo studies in GAA-knockout mice demonstrate that hepatic transduction with adenovirus encoding either murine or human GAA can provide a depot of recombinant enzyme that is available to heart and skeletal muscle through this mechanism. Taken together, these data show that the mannose 6-phosphate receptor pathway provides a useful strategy for cell-to-cell distribution of virally derived recombinant GAA.


Assuntos
Técnicas de Transferência de Genes , Terapia Genética/métodos , Doença de Depósito de Glicogênio Tipo II/genética , Doença de Depósito de Glicogênio Tipo II/terapia , alfa-Glucosidases/genética , Adenoviridae/genética , Animais , Western Blotting , Células Cultivadas , Técnicas de Cocultura , DNA Complementar/metabolismo , Fibroblastos/metabolismo , Humanos , Imuno-Histoquímica , Lisossomos/metabolismo , Manosefosfatos/metabolismo , Camundongos , Camundongos Knockout , Camundongos Nus , Músculo Esquelético/citologia , Miocárdio/metabolismo , Placenta/metabolismo , Receptor IGF Tipo 2/metabolismo , Proteínas Recombinantes/metabolismo , Fatores de Tempo , Transdução Genética
13.
Ying Yong Sheng Tai Xue Bao ; 11(3): 435-40, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11767650

RESUMO

A Bohai Sea mass-balance ecopath model is constructed on the basis of fisheries resources data from the ecosystem survey conducted from April 1982 to May 1983. It is the first ecopath model which consists of 13 function groups (boxes), and only covers the main trophic flow in the Bohai Sea ecosystem. P/B and Q/B parameters (P: production, B: biomass, Q: consumption) for most groups were estimated from similar function groups in other ecopath models of the same latitude regions around. The value of EE (Ecotrophic Efficiency) is the main parameter to check the equilibration of the model. The EE parameters in the model are of high value (> 0.808) for most groups, because the fishing pressure was very high and small living organisms were being heavily preyed upon in the ecosystem. The biomass density of the species commercially utilized estimated by the model is 12.33 ton.km-2. Even though the value is low compared with the density in other ecosystems, such as Caribbean coral reef ecosystem and the Southern B.C. shelf model, it is higher than the value published by some papers on the Bohai Sea using other methods. Considering the lower value estimated by the stock assessment using bottom trawl survey data, the output here is reasonable. It is concluded that the biomass of commercial fishing species in the sea is 950 thousand metric tons, and 338 thousand tons are fish species in the value.


Assuntos
Biomassa , Modelos Biológicos , Animais , China , Crustáceos/crescimento & desenvolvimento , Ecossistema , Peixes/crescimento & desenvolvimento , Moluscos/crescimento & desenvolvimento , Oceanos e Mares , Plâncton/crescimento & desenvolvimento
14.
J Cardiovasc Pharmacol Ther ; 5(4): 249-58, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11150394

RESUMO

Metabolic support for the heart has been an attractive concept since the pioneering work of Sodi-Pallares et al. four decades ago.* Recently, interest has increased in the use of over-the-counter supplements and naturally occurring nutriceuticals for enhancement of cardiac and skeletal muscle performance. These include amino acids such as creatine, L-carnitine, and L-arginine, as well as vitamins and cofactors such as alpha-tocopherol and coenzyme Q. Like these other molecules, D-ribose is a naturally occurring compound. It is the sugar moiety of ATP and has also received interest as a metabolic supplement for the heart. The general hypothesis is that under certain pathologic cardiac conditions, nucleotides (particularly ATP, ADP, and AMP) are degraded and lost from the heart. The heart's ability to resynthesize ATP is then limited by the supply of D-ribose, which is a necessary component of the adenine nucleotide structure. In support of this hypothesis, recent reports have used D-ribose to increase tolerance to myocardial ischemia. Its use in patients with stable coronary artery disease improves time to exercise-induced angina and electrocardiographic changes. In conjunction with thallium imaging or dobutamine stress echocardiography, D-ribose supplementation has been used to enhance detection of hibernating myocardium. In this article, we review the biochemical basis for using supplemental D-ribose as metabolic support for the heart and discuss the experimental evidence for its benefit.


Assuntos
Suplementos Nutricionais , Metabolismo Energético , Isquemia Miocárdica/fisiopatologia , Miocárdio/metabolismo , Ribose/farmacologia , Trifosfato de Adenosina/biossíntese , Animais , Cardiomegalia/fisiopatologia , Doença das Coronárias/fisiopatologia , Doença das Coronárias/prevenção & controle , Modelos Animais de Doenças , Coração/efeitos dos fármacos , Coração/fisiologia , Humanos , Músculo Liso/fisiologia , Contração Miocárdica/fisiologia , Isquemia Miocárdica/prevenção & controle , Estresse Oxidativo , Ratos , Ribose/farmacocinética , Ribose/uso terapêutico
15.
Clin Cardiol ; 22(3): 233-5, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10084069

RESUMO

Although unusual in the older patient, coarctation of the aorta can be an occult cause of cardiomyopathy. This report describes a 53-year-old man with new-onset heart failure symptoms, global left ventricular (LV) dysfunction, and underlying aortic coarctation. Surgical correction resulted in reduced LV size, resolution of symptoms, and normalization of atrial natriuretic hormone levels.


Assuntos
Coartação Aórtica/cirurgia , Fator Natriurético Atrial/sangue , Ventrículos do Coração/patologia , Coartação Aórtica/sangue , Coartação Aórtica/complicações , Cardiomiopatia Dilatada/etiologia , Cardiomiopatia Dilatada/patologia , Humanos , Masculino , Pessoa de Meia-Idade
16.
Gene Ther ; 5(4): 473-80, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9614571

RESUMO

The enzyme acid alpha-glucosidase catalyzes the breakdown of lysosomal glycogen. Absence of this enzyme results in infantile Pompe disease, characterized by hypertrophic cardiomyopathy, skeletal muscle weakness and fatal heart failure by 2 years of age. We have examined the possibility of gene replacement therapy for this disease, by constructing an E1-deleted recombinant adenovirus encoding human acid alpha-glucosidase (Ad-GAA). The dose-response in fibroblasts from patients with Pompe disease transduced with this vector is linear over the range tested (one to 2000 plaque forming units (p.f.u.) of Ad-GAA per cell), and acid alpha-glucosidase activity comparable to that of normal fibroblasts is achieved at 100 p.f.u. per cell. Targeting of the recombinant protein to the lysosomal compartment was confirmed by immunocytochemistry. In vivo expression was examined by injecting Ad-GAA into newborn rats; intracardiac administration produced 10 times the normal level of acid alpha-glucosidase activity in whole heart lysates, while a hind-limb i.m. injection increased activity in that muscle to six times the normal level. Western blotting of these tissues defected species at 76 kDa consistent with the size of processed lysosomal enzyme, and levels of expression as high as 1.0 mg recombinant protein per gram of tissue wet weight were produced. These data demonstrate high-level, lysosomal expression of recombinant acid alpha-glucosidase in treated target tissues and support the feasibility of gene replacement strategies for Pompe disease.


Assuntos
Adenoviridae , Fibroblastos/enzimologia , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Glucana 1,4-alfa-Glucosidase/genética , Doença de Depósito de Glicogênio Tipo II/terapia , Animais , Animais Recém-Nascidos , Western Blotting , Células Cultivadas , Expressão Gênica , Glucana 1,4-alfa-Glucosidase/metabolismo , Doença de Depósito de Glicogênio Tipo II/metabolismo , Humanos , Lisossomos , Masculino , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Ratos , Ratos Sprague-Dawley , Transgenes , alfa-Glucosidases
17.
Science ; 279(5352): 860-3, 1998 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-9452385

RESUMO

The mean trophic level of the species groups reported in Food and Agricultural Organization global fisheries statistics declined from 1950 to 1994. This reflects a gradual transition in landings from long-lived, high trophic level, piscivorous bottom fish toward short-lived, low trophic level invertebrates and planktivorous pelagic fish. This effect, also found to be occurring in inland fisheries, is most pronounced in the Northern Hemisphere. Fishing down food webs (that is, at lower trophic levels) leads at first to increasing catches, then to a phase transition associated with stagnating or declining catches. These results indicate that present exploitation patterns are unsustainable.

18.
Trends Ecol Evol ; 12(11): 442, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21238144
19.
Trends Ecol Evol ; 10(10): 430, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21237093
20.
Circ Res ; 68(4): 1085-94, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2009609

RESUMO

The sensitivity of carnitine palmitoyl coenzyme A (CoA) transferase I to inhibition of its activity by malonyl-CoA is progressively reduced in mitochondria isolated from ischemic cardiac cells as blood flow decreases to 30% or less of the preocclusion flow. The activity of carnitine palmitoyl-CoA transferase I in mitochondria isolated from nonischemic cardiac cells demonstrates incomplete inhibition, even at high concentrations of malonyl-CoA. Kinetic analyses of these data gave results most consistent with the expression of two overt enzyme activities: one activity that is sensitive to inhibition by malonyl-CoA and one activity that demonstrates little or no sensitivity to such inhibition. The decrease in malonyl-CoA-sensitive activity associated with ischemia results from a 13% decrease in the activity of the sensitive component and a corresponding 13% increase in the activity of the insensitive component. Decreased sensitivity of ischemic carnitine palmitoyl-CoA transferase I to inhibition by malonyl-CoA, together with potential fluctuations in the content of malonyl-CoA in tissue, would increase the synthesis of palmitoylcarnitine during ischemia and facilitate return to the use of fatty acid as a preferred metabolic fuel on reperfusion. This apparent conversion occurs concomitantly with a decrease in the free protein thiol content of the mitochondrial membranes isolated from ischemic cardiac cells. Treatment of the mitochondria from ischemic cardiac cells with dithiothreitol in vitro partially reverses the loss in sensitivity to malonyl-CoA, suggesting the possible role of thiol oxidation in the altered metabolism of ischemic mitochondria. Western blot analysis of these mitochondria using an antibody against carnitine palmitoyltransferase II purified from beef heart demonstrates a 68-kDa protein, which under ischemic conditions apparently is decreased by 2 kDa. These results are more indicative of a modification in protein folding of carnitine palmitoyltransferase than proteolytic changes during ischemia.


Assuntos
Carnitina O-Palmitoiltransferase/metabolismo , Doença das Coronárias/enzimologia , Mitocôndrias Cardíacas/enzimologia , Animais , Carnitina O-Palmitoiltransferase/isolamento & purificação , Circulação Coronária , Doença das Coronárias/fisiopatologia , Ditiotreitol/farmacologia , Cães , Ácidos Graxos/metabolismo , Immunoblotting , Cinética , Valores de Referência , Fluxo Sanguíneo Regional
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