Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-22742589

RESUMO

Climate change will affect the development of cereal crops and the occurrence of mycotoxins in these crops, but so far little research has been done on quantifying the expected effects. The aim of this study was to assess climate change impacts on the occurrence of deoxynivalenol in wheat grown in north-western Europe by 2040, considering the combined effects of shifts in wheat phenology and climate. The study used climate model data for the future period of 2031-2050 relative to the baseline period of 1975-1994. A weather generator was used for generating synthetic series of daily weather data for both the baseline and the future periods. Available models for wheat phenology and prediction of deoxynivalenol concentrations in north-western Europe were used. Both models were run for winter wheat and spring wheat, separately. The results showed that both flowering and full maturation of wheat will be earlier in the season because of climate change effects, about 1 to 2 weeks. Deoxynivalenol contamination was found to increase in most of the study region, with an increase of the original concentrations by up to 3 times. The study results may inform governmental and industrial risk managers to underpin decision-making and planning processes in north-western Europe. On the local level, deoxynivalenol contamination should be closely monitored to pick out wheat batches with excess levels at the right time. Using predictive models on a more local scale could be helpful to assist other monitoring measures to safeguard food safety in the wheat supply chain.


Assuntos
Mudança Climática , Produtos Agrícolas/química , Contaminação de Alimentos , Fungos/metabolismo , Modelos Biológicos , Tricotecenos/análise , Triticum/química , Agricultura/tendências , Animais , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/microbiologia , Europa (Continente) , Topos Floridos/crescimento & desenvolvimento , Previsões/métodos , Fungos/crescimento & desenvolvimento , Fusarium/crescimento & desenvolvimento , Fusarium/metabolismo , Humanos , Modelos Estatísticos , Estações do Ano , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/microbiologia , Análise Espaço-Temporal , Tricotecenos/biossíntese , Triticum/crescimento & desenvolvimento , Triticum/microbiologia , Tempo (Meteorologia)
2.
Eur J Vasc Endovasc Surg ; 34(1): 44-9, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17400486

RESUMO

OBJECTIVES: To compare polytetrafluorethylene (PTFE) and polyester grafts (Dacron) for above knee femoropopliteal bypass. DESIGN: Multicenter randomised clinical trial. MATERIAL AND METHODS: 427 patients were randomised between 6mm Dacron (Uni-Graft, B. Braun Melsungen AG, 34212 Melsungen, Germany) and PTFE (Goretex, W. L. Gore & Ass. Inc., Newark DE 19711, USA) above-knee femoropopliteal bypass grafts within 13 centres in Denmark (n=261), Norway (n=113) & Finland (n=53) between 1993 and 1998. Fourteen (3%) patients were excluded, leaving 413 patients with 208 Dacron and 205 PTFE grafts for analysis. Age, gender, indication (claudication: 65%), run-off (2 or 3 vessels: 76%), diabetes (17%) and hypertension (31%) as well as cerebrovascular (9%) and cardiac (33%) risks were evenly distributed. Patients were followed postoperatively at 1, 12 and 24 months. Patency assessment was based on ankle-brachial pressures or imaging in case of doubt. RESULTS: The two-year primary patency rates for Dacron and PTFE were 70% and 57% (p=0.02), whereas the secondary patency rates were 76% and 65% (p=0.04), respectively. Primary patency at two years was significantly influenced by the number of patent crural vessels (two or three 67%, one 50%, p=0.01). Amputations at two years, major in 4% and minor in 3%, 30-days mortality and complications (wound infections: 3% and other wound complications: 13%) occurred equally frequent in both groups. At two years, patients treated for critical limb ischemia had a major amputation more often than patients operated on for intermittent claudication, 10 and 3 respectively (p=0.003), and had higher mortality rates, 20% and 8% respectively (p=0.001). CONCLUSION: This trial confirms that Dacron is at least as durable as PTFE for above-knee bypass procedures, and might even be superior.


Assuntos
Prótese Vascular , Artéria Femoral/cirurgia , Isquemia/cirurgia , Perna (Membro)/irrigação sanguínea , Polietilenotereftalatos , Politetrafluoretileno , Artéria Poplítea/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia , Implante de Prótese Vascular/instrumentação , Feminino , Artéria Femoral/diagnóstico por imagem , Seguimentos , Humanos , Isquemia/diagnóstico , Isquemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Artéria Poplítea/diagnóstico por imagem , Desenho de Prótese , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia , Grau de Desobstrução Vascular
4.
FEMS Microbiol Lett ; 160(1): 75-9, 1998 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-9495015

RESUMO

NADP(+)-specific isocitrate dehydrogenase (EC 1.1.1.42) was purified to homogeneity from the sulfate-reducing bacterium Desulfobacter vibrioformis, and shown to be a monomeric protein with a molecular mass of 80 kDa. The pH and temperature optima were 8.5 and 45 degrees C, respectively. The N-terminal amino acid sequence (Thr, Glu, Thr, Ile, Arg, Trp, Thr, X, Thr, Asp, Glu, Ala, Pro, Leu, Leu, Ala, Thr) showed similarity with that of other known monomeric isocitrate dehydrogenases. Catalytically active isocitrate dehydrogenase from D. vibrioformis was obtained by activity staining after SDS-PAGE and removal of SDS from the gel. This technique revealed a NADP(+)-dependent monomeric enzyme in other Desulfobacter spp., Desulfuromonas acetoxidans and Chlorobium tepidium. These findings imply that monomeric isocitrate dehydrogenases are present in distantly related bacteria and indicate an early evolution of monomeric isocitrate dehydrogenases in the bacterial lineage.


Assuntos
Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/isolamento & purificação , Bactérias Redutoras de Enxofre/enzimologia , Bactérias Redutoras de Enxofre/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Evolução Biológica , Ciclo do Ácido Cítrico/fisiologia , Eletroforese em Gel de Poliacrilamida , Isocitrato Desidrogenase/metabolismo , Dados de Sequência Molecular , NADP/metabolismo , Homologia de Sequência de Aminoácidos
5.
Ugeskr Laeger ; 160(3): 273-6, 1998 Jan 12.
Artigo em Dinamarquês | MEDLINE | ID: mdl-9454395

RESUMO

Five hundred and ninety-nine patients with traumatic wounds of hands or feet with underlying lesions of the bone, tendon or joint, were randomized to double blind treatment with either A) one injection of penicillin, B) penicillin tablets for six days or C) no antibiotic treatment. In group A the infection rate was 4.9%, in group B it was 6.6% and in group C 10.2%. The difference between the infection rates in group A and C was 5.3% with a 95% confidence interval (CI) from 0.1 to 10.4%, (p = 0.046). Correction for an interim analysis and subgroup analysis increases this p-value to 0.096. The difference between the infection rates in group B and C was 3.6% (95%, CI from -1.9 to 8.9%, p = 0.20). Patients in group B had gastrointestinal complaints five times as often as patients in group A and C. Based on the results we advise that a single prophylactic injection of penicillin is given to patients with these injuries.


Assuntos
Traumatismos do Pé/complicações , Traumatismos da Mão/complicações , Penicilina G/administração & dosagem , Penicilina V/administração & dosagem , Infecção dos Ferimentos/prevenção & controle , Adolescente , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecção dos Ferimentos/microbiologia
6.
J Theor Biol ; 184(2): 111-6, 1997 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-9059590

RESUMO

Antiviruses are designed to inhibit virus replication and arrest infections. A particular antivirus derives from a specific virus, on which it depends for propagation. Antiviruses have a natural equivalent in defective interfering particles (DIPs). To obtain design criteria for antiviruses, antivirus therapies for treating virus infections are modelled by a system of equations with continuous dynamics. The results reveal that such therapies can eliminate viruses given either a large but achievable inoculum of antivirus or an outcompeting advantage to the antivirus. Since such therapies are relatively insensitive to many parameters of infections, they may be applicable to many viral diseases.


Assuntos
Viroses/terapia , Replicação Viral , Biotecnologia , Vírus Defeituosos , Humanos , Modelos Biológicos , RNA Catalítico , Interferência Viral , Viroses/virologia
7.
Acta Biotheor ; 44(3-4): 209-18, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8953210

RESUMO

To discover a unifying theory of biology, it is necessary first to believe in its existence and second to seek its elements. Such a theory would explain the regulation of the cell cycle, differentiation and the origin of life. Some elements of the theory may be obtained by considering both eukaryotic and prokaryotic cell cycles. These elements include cytoskeletal proteins, calcium, cyclins, protein kinase C, phosphorylation, transcriptional sensing, autocatalytic gene expression and the physical properties of lipids. Other more exotic candidate elements include the dynamic enzoskeleton, ATP generation, mechanotransduction, the piezoelectric effect and resonance. Bringing these disparate elements together--and discovering others--will require extensive collaborations between specialists from different sciences. This can only be achieved within the context of an integrated approach to biology.


Assuntos
Ciclo Celular/fisiologia , Diferenciação Celular/fisiologia , Sobrevivência Celular/fisiologia , Modelos Biológicos , Origem da Vida , Animais , Células Eucarióticas/fisiologia , Humanos
8.
Injury ; 27(4): 275-8, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8762789

RESUMO

The purpose of the study was to examine the effect of prophylactic penicillin treatment on the infection rate in patients with traumatic wounds of hands or feet with underlying lesions of bone, tendon or joint. A total of 599 patients were randomized to double-blind treatment with either (A) one injection of penicillin G, (B) penicillin V tablets for 6 days or (C) no antibiotic treatment. In group A the infection rate was 4.9 per cent, in group B 6.7 per cent and in group C 10.2 per cent. The difference between the infection rates in group A and C was 5.3 per cent with a 95 per cent confidence interval (CI) from 0.1 to 10.4 per cent (P = 0.046). Correction for an interim analysis and subgroup analyses increases this P value to 0.096. The difference between the infection rates in group B and C was 3.6 per cent (95 per cent CI from -1.9 to 8.9, P = 0.20). Patients in group B had gastrointestinal complaints five times as often as patients in group A and C. Prophylactic tablets for 6 days require patients' co-operation while an injection ensures that the prophylaxis is given. We therefore conclude that a single prophylactic injection of two million units of penicillin G is advisable for patients with these injuries.


Assuntos
Traumatismos do Pé/cirurgia , Traumatismos da Mão/cirurgia , Penicilina G/uso terapêutico , Penicilina V/uso terapêutico , Penicilinas/uso terapêutico , Infecção da Ferida Cirúrgica/prevenção & controle , Adolescente , Adulto , Idoso , Método Duplo-Cego , Feminino , Traumatismos do Pé/complicações , Traumatismos da Mão/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Fatores de Tempo
9.
J Mol Biol ; 253(5): 739-48, 1995 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-7473748

RESUMO

When bacteria contain two chromosomes, two or more copies of the same gene are present in the same cytoplasm and, if these copies are subject to negative regulation in trans and positive (autocatalytic) regulation in cis, one copy will be expressed at the expense of the other copy(ies). This autocatalytic process depends on the coupled transcription, or translation and insertion of nascent proteins into the membrane, or transertion. Transertion is responsible for looping genes out of the nucleoid and increasing their accessibility to transcription factors. Transertion of proteins with lipid preferences creates proteolipid domains in the membrane. These domains fuse to give two types of large domains, each associated with the expression of a particular set of genes. These large domains organize kinases, proteases and transcription factors and result in the expression of one set of genes encoding proteins with common lipid preferences from one chromosome and expression of a different set from the other. These intracellular differences underlie the production of different progeny by cell division that follows, for example, reception of extracellular signals, and that constitutes differentiation in bacteria.


Assuntos
Proteínas de Bactérias/metabolismo , Cromossomos Bacterianos/metabolismo , DNA Bacteriano/genética , Regulação Bacteriana da Expressão Gênica , Lipídeos de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Modelos Genéticos , Proteolipídeos/metabolismo , Catálise , Divisão Celular , Endopeptidases/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/ultraestrutura , Genes Bacterianos , Substâncias Macromoleculares , Fosfotransferases/metabolismo , Biossíntese de Proteínas , Ribonucleases/metabolismo , Transcrição Gênica
10.
Trends Microbiol ; 1(9): 355-7, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8162427

RESUMO

Potentially, antiviruses that interfere with HIV propagation could be used as AIDS therapy. If problems associated with HIV recombination and the dynamics of the interactions between HIV and antivirus can be resolved by an appropriate design, an antivirus might defer or prevent the development of AIDS, and might benefit AIDS patients.


Assuntos
Síndrome da Imunodeficiência Adquirida/terapia , Vírus Defeituosos/fisiologia , Humanos
11.
Ugeskr Laeger ; 152(36): 2550-2, 1990 Sep 03.
Artigo em Dinamarquês | MEDLINE | ID: mdl-2402840

RESUMO

A questionnaire about prophylactic antibiotic treatment of open bone, tendon or joint lesions in the extremities was sent to the 83 casualty departments in Denmark. The questionnaire was answered by 56 casualty departments which treated 72% of the orthopaedic surgical injuries in Denmark. In cases of lesions of the hands and feet, 23% of the patients were treated in casualty departments where prophylactic antibiotic therapy was rarely employed while 24% were treated in casualty departments where prophylactic antibiotic therapy was always employed. In cases of lesions proximal to the wrist or ankle joints, the figures were 26% and 38%, respectively. Penicillin was nearly always employed and treatment was commenced before or during operation. The majority of departments continued treatment for four days or longer. Considerable scatter was reported in the dosage of penicillin employed. The literature about prophylactic antibiotic treatment in cases of complicated lesions of the extremities is insufficient and controlled investigations are necessary to elucidate a series of conditions.


Assuntos
Traumatismos do Braço/tratamento farmacológico , Traumatismos da Perna/tratamento farmacológico , Penicilinas/administração & dosagem , Traumatismos do Braço/complicações , Traumatismos do Braço/cirurgia , Humanos , Traumatismos da Perna/complicações , Traumatismos da Perna/cirurgia , Infecção da Ferida Cirúrgica/prevenção & controle , Inquéritos e Questionários
12.
Ugeskr Laeger ; 152(27): 1985-7, 1990 Jul 02.
Artigo em Dinamarquês | MEDLINE | ID: mdl-2195735

RESUMO

During the years 1983-1987, 1,266 operations for abdominal aortic aneurysm (AAA) were carried out in eight surgical departments with vascular surgical function. The activity increased constantly corresponding to 311 patients in 1987 or 50% more than in 1983. During this period the distribution between patients subjected to elective operation and those operated upon as emergencies was very uniform. In the latter group, only a slight increase in the number of AAA patients with rupture was observed. The risk of complications was low with a significant decrease in the need for dialysis. The early mortality was constant for the patients subjected to elective operation remained constant about 5.5%. A marked decrease in the early mortality was observed for the patients operated upon as emergencies with rupture from 63 to 50% and without rupture from 37 to 25%. At the conclusion of the period, ultrasonic scanning became the preoperative investigation of election and introduction of an aortic prosthesis the method of operation of election. Patients with AAA should be recognized so that elective surgery can be offered before a condition endangering life develops.


Assuntos
Aneurisma Aórtico/cirurgia , Adulto , Idoso , Aorta Abdominal/cirurgia , Aneurisma Aórtico/diagnóstico , Ruptura Aórtica/cirurgia , Dinamarca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Estudos Retrospectivos , Ultrassonografia
13.
Scand J Gastroenterol ; 21(10): 1180-4, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3809993

RESUMO

A Danish, randomized study with Hemoccult-II, including 60,000 persons between 45 and 74 years old, began in 1985. Methods of increasing acceptability are described for the first 8000. The first 1000 refusals are also analyzed. Written invitations including prestamped envelopes for return of the slides resulted in an acceptability of 58.8%. Two reminders increased the figure to 65.6%. Personal attempts to change the mind of those refusing increased the last figure to 68.9%. Incomplete slides were returned by 49 persons, but on request 43 sent a complete set. All 78 persons with positive tests had colonoscopy, which detected carcinomas in 10 and adenomas in 39. The study confirmed that results of trials from different countries are difficult to compare because of major differences among populations and methods. However, the present results were similar to those obtained in a Swedish study including only persons between 60 and 64 years old.


Assuntos
Neoplasias do Colo/prevenção & controle , Programas de Rastreamento/organização & administração , Sangue Oculto , Neoplasias Retais/prevenção & controle , Idoso , Dinamarca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Ann Surg ; 204(1): 72-7, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3729585

RESUMO

Isolated obstruction of the splenic vein leads to segmental portal hypertension, which is a rare form of extrahepatic portal hypertension, but it is important to diagnose, since it can be cured by splenectomy. In a review of the English literature, 209 patients with isolated splenic vein obstruction were found. Pancreatitis caused 65% of the cases and pancreatic neoplasms 18%, whereas the rest was caused by various other diseases. Seventy-two per cent of the patients bled from gastroesophageal varices, and most often the bleeding came from isolated gastric varices. The spleen was enlarged in 71% of the patients. A correct diagnosis in connection with the first episode of bleeding was made in only 49%; 22% were operated on because of gastrointestinal bleeding, but the cause of bleeding was not found. The diagnosis should be suspected in patients with gastroesophageal varices, but without signs of a liver disease, especially if isolated gastric varices are found. The diagnosis is confirmed by portography.


Assuntos
Hipertensão Portal/etiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Varizes Esofágicas e Gástricas/complicações , Feminino , Humanos , Hipertensão Portal/complicações , Hipertensão Portal/diagnóstico , Hipertensão Portal/cirurgia , Lactente , Masculino , Pessoa de Meia-Idade , Esplenectomia , Veia Esplênica
15.
Acta Chir Scand ; 152: 393-5, 1986 May.
Artigo em Inglês | MEDLINE | ID: mdl-3488630

RESUMO

Isolated splenic vein obstruction may lead to bleeding from gastric varices. The condition is rare, the varices may be difficult to demonstrate and therefore the diagnosis often is delayed. This is illustrated by an example of a 79-year-old man who had intermittent melena for two years before the diagnosis was made. Following splenectomy there was no bleeding.


Assuntos
Hemorragia Gastrointestinal/etiologia , Melena/etiologia , Veia Esplênica , Trombose/complicações , Idoso , Carcinoma/patologia , Varizes Esofágicas e Gástricas/etiologia , Humanos , Neoplasias Hepáticas/secundário , Masculino , Metástase Neoplásica , Neoplasias Pancreáticas/patologia , Veia Esplênica/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...