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1.
Rev Sci Instrum ; 92(2): 023205, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648096

RESUMO

Many samples of current interest in molecular physics and physical chemistry exist in the liquid phase and are vaporized for use in gas cells, diffuse gas targets, or molecular gas jets. For some of these techniques, the large sample consumption is a limiting factor. When rare, expensive molecules such as custom-made chiral molecules or species with isotopic labels are used, wasting them in the exhaust line of the pumps is quite an expensive and inefficient approach. Therefore, we developed a closed-loop recycling system for molecules with vapor pressures below atmospheric pressure. Once filled, only a few valves have to be adjusted, and a cold trap must be moved after each phase of recycling. The recycling efficiency per turn exceeds 95%.

2.
Br J Ophthalmol ; 97(3): 333-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23335208

RESUMO

AIMS: This study explored the association of active acute anterior uveitis (AAU) with depressive feelings and patients' general health. METHODS: This case-control study comprised 80 participants: 35 patients with an active case of AAU and 45 healthy peers were analysed to compare their depressive moods (Beck depression inventory (BDI), Zerssen Mood Scale (ZMS)) and general health (Short form-8 health survey (SF8)). Furthermore, patients were questioned regarding the presence of distress, occupational satisfaction and impairment in performing daily life tasks. RESULTS: During an acute attack, AAU patients were shown to suffer from depressive moods more often than their healthy peers (BDI 54% vs 9%, respectively; ZMS 2.7-fold shift in mood levels towards depression) and experienced a reduction in mental and physical scores (SF8). Patients felt impaired reading (94%), driving (69%) and working (69%). In all, 74% of the patients believed that distress was a probable trigger. Lack of occupational satisfaction was associated with a persistence of depressive feelings and a reduction in physical health. CONCLUSIONS: AAU patients exhibited a significant psychopathology towards depression, a reduction of general health and impairment of performing daily life tasks. Patients who were unsatisfied at work seemed to suffer even more. The results underline the importance of offering psychological support to the patients and providing information to patients and close social contacts.


Assuntos
Depressão/etiologia , Inquéritos Epidemiológicos , Inventário de Personalidade , Qualidade de Vida , Estresse Psicológico/etiologia , Uveíte Anterior/complicações , Doença Aguda , Adulto , Áustria/epidemiologia , Depressão/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Escalas de Graduação Psiquiátrica , Estudos Retrospectivos , Estresse Psicológico/epidemiologia , Inquéritos e Questionários , Uveíte Anterior/epidemiologia
3.
Br J Ophthalmol ; 95(5): 699-704, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20971789

RESUMO

BACKGROUND/AIMS: To evaluate depression, coping with disease and stress, and the subjective impression of distress and/or life events as triggers for recurrences in HLA-B27-associated anterior uveitis (B27-AU), with attention to gender-specific characteristics. METHODS: 171 patients with a history of B27-AU responded to a postal survey performed between January 2006 and April 2008 using standardised psychological questionnaires: Beck Depression Inventory, Freiburg Questionnaire on Coping with Illness, and Stress Coping Inventory. RESULTS: Patients with B27-AU differed from healthy controls showing more depressive symptoms (Beck Depression Inventory, 31.6%), applying characteristic disease coping as well as negative stress coping strategies. Female B27-AU patients tended to react with depression and male patients to use negative stress coping strategies. 57.9% of patients believed that psychological distress was a trigger for relapses, and 34.5% stated specific life events. Together, this group of patients achieved higher depression scores and used more negative disease and stress coping styles than patients without perception of distress. CONCLUSION: Patients with B27-AU patients exhibited significant psychopathology concerning depression and disease coping. Distress and life events were subjectively suspected to be a trigger. By imparting knowledge to the patients on probable development of depressive moods and the role of stress/life events as trigger for relapses, as well as offering behaviour therapy to optimise coping, may help patients to cope better with B27-AU.


Assuntos
Transtorno Depressivo/psicologia , Antígeno HLA-B27/imunologia , Estresse Psicológico/psicologia , Uveíte Anterior/psicologia , Adulto , Estudos Transversais , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/imunologia , Feminino , Antígeno HLA-B27/genética , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Recidiva , Fatores Sexuais , Estresse Psicológico/epidemiologia , Estresse Psicológico/imunologia , Inquéritos e Questionários , Uveíte Anterior/epidemiologia , Uveíte Anterior/genética , Uveíte Anterior/imunologia
4.
Appl Microbiol Biotechnol ; 63(2): 153-8, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-13680201

RESUMO

A cDNA coding for laccase was isolated from the white-rot fungus Trametes trogii 201. This cDNA corresponded to the lcc1 gene, which coded for a precursor protein of 517 amino acids with a 21 amino acid signal peptide. Comparison of the deduced sequence with known laccases showed that this enzyme was most closely related to Lac1 from basidiomycete PM1 and Trametes C30 (98% similarity). The expression of lcc1 was analysed under different growth conditions; transcription of this gene was enhanced by the addition of organic nitrogen to the medium. The level of lcc1 transcription was higher when T. trogii was grown on synthetic medium supplemented with yeast extract rather than mycological peptone or tryptone. The transcription data were in agreement with total laccase activity measured in the supernatant and suggested that laccase production and lcc1 transcription are coordinately regulated in this organism. The lcc1 cDNA was expressed in the methylotrophic yeast Pichia pastoris and the detection of laccase activity indicated that this cDNA encodes a laccase.


Assuntos
Basidiomycota/enzimologia , Lacase/genética , Lacase/metabolismo , Transcrição Gênica , Basidiomycota/genética , Basidiomycota/crescimento & desenvolvimento , Clonagem Molecular , Meios de Cultura , Regulação Fúngica da Expressão Gênica , Lacase/química , Dados de Sequência Molecular , Pichia/enzimologia , Pichia/genética , Análise de Sequência de DNA
5.
Shock ; 16(1): 25-7, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11442311

RESUMO

Procalcitonin (PCT) has been described as an early and discriminating marker of bacteria-associated sepsis in patients. However, little is known of its source and actions, especially with regard to its relation to tumor necrosis factor (TNF). TNF is responsible for the release of several other mediators of sepsis e.g., chemokines. We tested the hypothesis that plasma PCT levels during sepsis differ with regard to the degree of TNF availability. Severe hyperdynamic sepsis was induced in baboons (n = 14) by i.v. infusion of live E. coli (approximately 2 x 10(9) colony-forming units/kg) over 2 h. Animals were pretreated 2 h before E. coli either with 1 mg/kg humanized anti-TNF antibody (CDP571) or placebo (Ringer solution). Plasma PCT levels at baseline was barely detectable, but increased to about 4000 pg/mL at 4 h after E. coli infusion. Levels were maximal between 8 and 24 h and had returned nearly to baseline at 72 h. Although no TNF could be measured in the treated group, PCT levels were not different between the placebo and the TNF antibody treatment group. We conclude that PCT levels are not dependent on the systemic presence of TNF in an E. coli sepsis model in baboons. Such sepsis induced PCT release is clearly different from the previously reported PCT release during infusion of rhTNF in volunteers or chimpanzees.


Assuntos
Calcitonina/sangue , Precursores de Proteínas/sangue , Sepse/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Anticorpos/farmacologia , Citocinas/sangue , Modelos Animais de Doenças , Masculino , Papio , Sepse/tratamento farmacológico , Fator de Necrose Tumoral alfa/imunologia
6.
Appl Environ Microbiol ; 66(6): 2311-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10831404

RESUMO

From a ferulic-acid-degrading Pseudomonas fluorescens strain (BF13), we have isolated a transposon mutant, which retained the ability to bioconvert ferulic acid into vanillic acid but lost the ability to further degrade the latter acid. The mutant, BF13-97, was very stable, and therefore it was suitable to be used as a biocatalyst for the preparative synthesis of vanillic acid from ferulic acid. By use of resting cells we determined the effect on the bioconversion rate of several parameters, such as the addition of nutritional factors, the concentration of the biomass, and the carbon source on which the biomass was grown. The optimal yield of vanillic acid was obtained with cells pregrown on M9 medium containing p-coumaric acid (0.1% [wt/vol]) as a sole carbon source and yeast extract (0.001% [wt/vol]) as a source of nutritional factors. Under these conditions, 1 mg (wet weight) of biomass produced 0.23 mg of vanillic acid per h. The genomic region of BF13-97 flanking the transposon's site of insertion was cloned and sequenced revealing two open reading frames of 1,062 (vanA) and 954 (vanB) bp, respectively. The van genes are organized in a cluster and encode the subunits of the vanillate-O-demethylase, which catalyzes the first step of the vanillate catabolism. Amino acid sequences deduced from vanA and vanB genes were shown to have high identity with known VanAs and VanBs from Pseudomonas and Acinetobacter spp. Highly conserved regions known to exist in class IA oxygenases were also found in the vanillate-O-demethylase components from P. fluorescens BF13. The terminal oxygenase VanA is characterized by a conserved Rieske-type [2Fe-2S](R) ligand center. The reductase VanB contains a plant-type ferredoxin [2Fe-2S](Fd), flavin mononucleotide, and NAD-ribose binding domains which are located in its C-terminal and N-terminal halves, respectively. Transfer of wild-type vanAB genes to BF13-97 complemented this mutant, which recovered its ability to grow on either vanillic or ferulic acid.


Assuntos
Ácidos Cumáricos/metabolismo , Mutação , Oxirredutases O-Desmetilantes/genética , Pseudomonas fluorescens/genética , Ácido Vanílico/metabolismo , Sequência de Bases , Clonagem Molecular , Teste de Complementação Genética , Hidroxibenzoatos/metabolismo , Dados de Sequência Molecular , Oxirredutases/genética , Oxirredutases O-Desmetilantes/metabolismo , Oxigenases/genética , Filogenia , Pseudomonas fluorescens/metabolismo , Análise de Sequência de DNA
8.
J Infect Dis ; 171(6): 1522-7, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7769287

RESUMO

This study was designed to test whether thrombomodulin is shed in septic baboons and whether shedding is blocked by antibody to tumor necrosis factor (anti-TNF). Live Escherichia coli were injected intravenously into 24 baboons according to one of the following regimens: 5 x 10(8) or 2 x 10(9) cfu/kg (n = 6/8), 2 x 10(9) cfu/kg with placebo (n = 5), or pretreatment with 1 mg/kg anti-TNF 2 h before E. coli injection (n = 5). E. coli administration resulted in a significant release of thrombomodulin in a dose-dependent manner; however, thrombomodulin release was significantly attenuated (180 to 40 ng/mL) by anti-TNF pretreatment. This is parallel to the reduction of neutrophil activation (elastase). These results provide evidence for an E. coli dose-related and TNF-dependent thrombomodulin release into the plasma of septic baboons and suggest a possible role of anti-TNF in protection of the endothelium.


Assuntos
Sepse/metabolismo , Trombomodulina/metabolismo , Fator de Necrose Tumoral alfa/fisiologia , Alanina Transaminase/sangue , Animais , Escherichia coli , Masculino , Elastase Pancreática/sangue , Papio , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Contagem de Plaquetas
9.
Am J Physiol ; 264(6 Pt 2): H2119-23, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8322941

RESUMO

Phospholipase A (PLA) activity is elevated in plasma after polytrauma and in sepsis. During both situations, tumor necrosis factor (TNF) and free fatty acids (FFAs) are also increased. To determine whether there is a relationship between the changes in PLA and in TNF that occur during sepsis, we used a primate model of bacteremia. Live Escherichia coli (5 x 10(8) colony-forming units/kg) was injected into anesthetized baboons (n = 10). Four of these animals were pretreated with an anti-TNF antibody (anti-TNF Ab, 15 mg/kg). After the administration of bacteria (2 h), the plasma TNF was 10.2 +/- 3.2 ng/ml. PLA and FFA reached their maximum values of 191 +/- 14 U/l and 1.5 +/- 0.3 mM at 10 and 24 h after the injection of bacteria, respectively. In the animals treated with anti-TNF Ab, plasma TNF was undetectable; the highest values recorded for PLA and FFA were 71 +/- 23 U/l and 0.7 +/- 0.3 mM, respectively. Thus TNF appears to be an important mediator of PLA release during sepsis.


Assuntos
Bacteriemia/fisiopatologia , Infecções por Escherichia coli/enzimologia , Infecções por Escherichia coli/fisiopatologia , Fosfolipases A/metabolismo , Fator de Necrose Tumoral alfa/fisiologia , Animais , Anticorpos/imunologia , Bacteriemia/enzimologia , Ácidos Graxos não Esterificados/metabolismo , Masculino , Papio , Fator de Necrose Tumoral alfa/imunologia
10.
J Lipid Mediat ; 2 Suppl: S195-201, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2133282

RESUMO

It has been reported that a platelet-activating factor (PAF) antagonist ONO-6240 had little effect on pulmonary hypertension and lung lymph in sheep injected with endotoxin lipopolysaccharide (LPS); consequently we evaluated a new PAF antagonist, BN 52021. Twelve adult sheep were surgically prepared for chronic study including lung lymph drainage. LPS (S. abortus equii, 36 ng/kg/h over 7 h) was then administered with (BN group) or without (control group) infusion (1 h before LPS) of the PAF antagonist BN 52021 (4 mg/kg/30 min). Comparison of the hemodynamic data between the control group and the BN group reveals an almost identical pattern. In contrast, we find differences in the pulmonary response of the two experimental groups. The early elevation of pulmonary artery pressure after LPS administration is less in the treatment group, as is the duration of pulmonary hypertension. Similarly, thromboxane levels are lower in the treated animals. The increases in lymph flow (LQ) and transvascular protein clearance (L/P X LQ) as well as the protein flux were less prominent in the treatment group. The mean lymph flow per hour was significantly higher in the control group. The mean lymph flow per hour was significantly higher in the control group, as were the corresponding parameters for clearance and protein flux. Thus the pulmonary vasculature and lung fluid balance disruption produced by LPS was markedly reduced by treatment with the PAF blocker.


Assuntos
Diterpenos , Lactonas/farmacologia , Fator de Ativação de Plaquetas/antagonistas & inibidores , Choque Séptico/prevenção & controle , Animais , Ginkgolídeos , Lactonas/administração & dosagem , Lipopolissacarídeos/administração & dosagem , Pulmão/efeitos dos fármacos , Pulmão/fisiopatologia , Linfa/efeitos dos fármacos , Circulação Pulmonar/efeitos dos fármacos , Ovinos , Choque Séptico/etiologia , Choque Séptico/fisiopatologia , Equilíbrio Hidroeletrolítico/efeitos dos fármacos
11.
Acta Orthop Scand ; 60(6): 693-5, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2624090

RESUMO

Demineralized bone matrix and bone-matrix gelatin prepared from cortical rat bone, and from cortical and cancellous canine bone were implanted into muscle pouches of nude rats for 6 weeks. Evaluation was done by histology, histomorphometry, and determination of alkaline phosphatase. Rat matrix consistently induced new bone and high phosphatase levels. Canine matrix induced but small amounts of bone and lower phosphatase levels, with cortical matrix somewhat more inductive than cancellous matrix; demineralized cancellous bone matrix from the dog was the only material tested not showing any inductivity. Irrespective of bone type or species, gelatin had clearly higher induction capacity than demineralized bone matrix.


Assuntos
Matriz Óssea/transplante , Osteogênese/fisiologia , Fosfatase Alcalina/metabolismo , Animais , Matriz Óssea/enzimologia , Cães , Masculino , Ratos , Ratos Endogâmicos , Ratos Nus , Especificidade da Espécie , Transplante Heterotópico
12.
Biol Met ; 2(1): 6-10, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2562042

RESUMO

Manganese accumulation was studied by room-temperature electron spin resonance (ESR) spectroscopy in Saccharomyces cerevisiae grown in the presence of increasing amounts of MnSO4. Mn2+ retention was nearly linear in intact cells for fractions related to both low-molecular-mass and macromolecular complexes ('free' and 'bound' Mn2+, respectively). A deviation from linearity was observed in cell extracts between the control value and 0.1 mM Mn2+, indicating more efficient accumulation at low Mn2+ concentrations. The difference in slopes between the two straight lines describing Mn2+ retention at concentrations lower and higher than 0.1 mM, respectively, was quite large for the free Mn2+ fraction. Furthermore it was unaffected by subsequent dialyses of the extracts, showing stable retention in the form of low-molecular-mass complexes. In contrast, the slope of the line describing retention of 'bound' Mn2+ at concentrations higher than 0.1 mM became less steep after subsequent dialyses of the cell extracts. This result indicates that the macromolecule-bound Mn2+ was essentially associated with particulate structures. In contrast to Cu2+, Mn2+ had no effect on the major enzyme activities involved in oxygen metabolism except for a slight increase of cyanide-resistant Mn-superoxide dismutase activity, due to dialyzable Mn2+ complexes.


Assuntos
Manganês/metabolismo , Saccharomyces cerevisiae/metabolismo , Superóxido Dismutase/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Saccharomyces cerevisiae/enzimologia , Temperatura
13.
Clin Orthop Relat Res ; (238): 282-7, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2463128

RESUMO

Allogeneic demineralized bone matrix (DBM) and bone matrix gelatin (BMG) were implanted with or without fibrin sealant (FS) ectopically (abdominal wall) and orthotopically (7-mm trepanation defect) in 38 male Sprague-Dawley rats. Evaluation was done by descriptive histology, histomorphometry of orthotopic implants, and determination of alkaline phosphatase in ectopic implants. The observation period was 21 days with ectopic implantation and 26 days with orthotopic implantation. In all ectopic specimens, new bone developed without any qualitative difference between specimens with and without FS. The alkaline phosphatase activity did not change significantly upon addition of FS. Morphometry revealed slight differences between the groups with and without FS. The peripheral bone deposits in the BMG + FS group, was significantly larger than in the BMG group. These investigations demonstrated neither a clearly positive nor negative effect of FS on ectopic osteoinduction or BMG-dependent osteoregeneration.


Assuntos
Aprotinina/farmacologia , Matriz Óssea/transplante , Regeneração Óssea/efeitos dos fármacos , Fator XIII/farmacologia , Fibrinogênio/farmacologia , Osteogênese/efeitos dos fármacos , Trombina/farmacologia , Adesivos Teciduais/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Osso e Ossos/enzimologia , Coristoma/fisiopatologia , Combinação de Medicamentos/farmacologia , Adesivo Tecidual de Fibrina , Masculino , Músculos , Ratos , Ratos Endogâmicos
17.
Int J Food Microbiol ; 7(1): 19-24, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2908612

RESUMO

The microbiological quality of fresh pasta dumplings sold in Bologna and the surrounding district was evaluated. A total of 60 lots (300 subsamples) of fresh pasta dumplings, both 'home-made' and manufactured, were analysed for aerobic plate count (APC), coliforms (total and fecal), Staphylococcus aureus, Clostridium perfringens and Salmonella spp. Thirty one of the 39 lots of 'home-made' pasta were found to exceed APC standards and six lots exceeded S. aureus standards. Five (24%) and six (29%) lots of the manufactured pasta were found to be unsatisfactory as regards APC standards and S. aureus standards respectively. The results obtained indicated that a high percentage of samples had a contamination of fecal origin. No Cl. perfringens or Salmonella spp. were found.


Assuntos
Bactérias/isolamento & purificação , Microbiologia de Alimentos/normas , Clostridium perfringens/isolamento & purificação , Contagem de Colônia Microbiana , Enterobacteriaceae/isolamento & purificação , Itália , Controle de Qualidade , Staphylococcus aureus/isolamento & purificação
18.
Biol Chem Hoppe Seyler ; 369 Suppl: 153-6, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3060136

RESUMO

Small doses of endotoxin have been shown to induce pulmonary microvascular injury in sheep, possibly by the action of granulocytes. Eglin, a potent inhibitor of neutrophil elastase, was tested in an ovine model of endotoxemia. The experiment was performed in 12 unanesthetized chronically instrumented sheep with a lung lymph preparation. Endotoxin (S. abort. equii) was infused at 24 ng/(kg x h) with application of 20 mg/kg eglin 1 h before endotoxin in the treatment group and followed by 5 mg/(kg x h). No significant improvement due to the treatment was seen for either cardiovascular status (pulmonary and systemic vascular resistance) or permeability changes in the lung (lymph flow and lymph/plasma protein ratio), although sufficient eglin concentrations were achieved in plasma and lymph. The lack of an effect of eglin might be because higher concentrations are needed to block elastase-like activity of ovine granulocytes or because of a minor role for neutrophil elastase in this shock model.


Assuntos
Elastase Pancreática/antagonistas & inibidores , Proteínas/uso terapêutico , Serpinas , Toxemia/tratamento farmacológico , Animais , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Endotoxinas , Escherichia coli , Granulócitos/efeitos dos fármacos , Humanos , Técnicas In Vitro , Contagem de Leucócitos , Sistema Linfático/efeitos dos fármacos , Proteínas/farmacocinética , Ovinos , Tromboxano B2/sangue
19.
Acta Orthop Scand ; 59(2): 165-7, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3364186

RESUMO

Bone matrix gelatin induces bone formation in muscle, and when implanted orthotopically it improves bone repair. Co-60 sterilization of bone gelatin impairs the protein-bound induction mechanisms. Gelatin samples nonirradiated or irradiated by 25 or 50 kGy were implanted into a pouch in the abdominal wall of Sprague-Dawley rats, as well as into a 7-mm calvarial defect. Evaluation was done by histologic studies, histomorphometry of orthotopic implants, and determination of alkaline phosphatase in ectopic implants. Gelatin irradiated with 50 kGy was absorbed in the muscle bed without evidence of any specific host reaction. Irradiation of 25 kGy led to histologically confirmed ectopic bone formation, but the wet weight of the explants was only half that of the nonirradiated control samples. Alkaline phosphatase activity was equal in both of these groups. With orthotopic implantation, neither a histologic nor a morphometric effect was seen with 25 kGy. Loss of osteoinduction with 25-kGy irradiation is apparently masked by osteoconductive mechanisms with orthotopic implantation.


Assuntos
Desenvolvimento Ósseo/efeitos da radiação , Matriz Óssea/efeitos da radiação , Radioisótopos de Cobalto , Esterilização/métodos , Fosfatase Alcalina/análise , Animais , Matriz Óssea/enzimologia , Radioisótopos de Cobalto/administração & dosagem , Relação Dose-Resposta à Radiação , Gelatina/efeitos da radiação , Ratos , Ratos Endogâmicos
20.
Biochim Biophys Acta ; 965(1): 46-51, 1988 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-2831994

RESUMO

Aerobic growth of Saccharomyces cerevisiae in the presence of CuSO4 (between 0.1 and 1 mM) caused a generalized induction of major enzyme activities involved in 'housekeeping' routes of oxygen metabolism (cytochrome oxidase, glutathione peroxidases and catalase) which were comparable to or higher than that observed with Cu,Zn-superoxide dismutase. Fumarase and glutathione transferase, tested as controls for oxygen-unrelated activities, were found to decrease under the same conditions. In the absence of oxygen, copper addition to yeast resulted in significant increases of Cu,Zn-superoxide dismutase and glutathione peroxidases and a slight increase of cytochrome oxidase, with catalase remaining undetectable irrespective of whether or not copper was present. Other metal ions tested (Mn2+, Co2+) were unable to produce such effects. It is concluded that copper has a general inducing effect on enzymes related to metabolism of oxygen and oxygen derivatives, which is mediated neither by formation of O2-. and H2O2 nor by interaction with copper-specific apoproteins. These results point to a general role of copper as regulator of the expression of major enzyme activities involved in biological oxygen activation.


Assuntos
Cobre/farmacologia , Oxigênio/metabolismo , Saccharomyces cerevisiae/enzimologia , Aerobiose , Anaerobiose , Catalase/biossíntese , Complexo IV da Cadeia de Transporte de Elétrons/biossíntese , Indução Enzimática/efeitos dos fármacos , Glutationa Peroxidase/biossíntese , Selênio/farmacologia , Superóxido Dismutase/biossíntese
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