RESUMO
The occurrence of furan in some food products has already been known for a few decades, and it has been reconfirmed in more recent investigations that furan is present in a variety of foodstuffs. This list of products includes roasted coffee, which has been shown to generate furan as a result of the heat treatment at roasting which is applied to achieve the desired aroma and flavour profile of a roasted coffee. The objective of this study is to provide data to allow a better understanding of the available data of furan in coffee, the kinetics of furan generated during roasting, and to estimate the reduction of furan levels afterwards due to subsequent processing steps and consumer handling. Finally, the study is meant as a contribution to establish exposure data on the basis of scientific data at the stage of coffee consumption. This paper shows that the formation of furan during roasting is dependent on roasting conditions and is, therefore, directly linked to achieving targeted flavour profiles. Furthermore, it is demonstrated that modifications in process conditions potentially to reduce furan levels may have the opposite effect on other undesired reaction products of the roasting chemistry such as, for example, acrylamide. Due to the high volatility of furan, any subsequent processing step or consumer handling has an impact on the level of furan. As a guidance from this study and in consideration of the identified losses of each process and handling step on the basis of the trial conditions, it is estimated that only approximately 10% of the initially generated furan during roasting gets into the cup of coffee for consumption.
Assuntos
Coffea/química , Café/química , Contaminação de Alimentos/análise , Furanos/química , Sementes/química , Manipulação de Alimentos , Projetos PilotoRESUMO
The aim of this study was to explore intensive care nurses' experiences of focus group-oriented supervision with particular reference to family members' needs. In addition, the aim was to focus on the intensive care nurses' perceived change in their insight into caring for patients and family members in an intensive care unit. Four themes were constructed: increased perception of and response to the family members' needs; increased self-insight related to the therapeutic use of oneself in the relationship with patients and their family members; nurses' reflection on factors that increased their competence; and increased creativity. In conclusion, focus group-oriented supervision increased the intensive care nurses' understanding of their role. This has consequences not only for the family members but also for the teamwork in the intensive care unit, where this type of work is common.
Assuntos
Competência Clínica , Família , Grupos Focais , Unidades de Terapia Intensiva/organização & administração , Recursos Humanos de Enfermagem Hospitalar/psicologia , Humanos , Relações Enfermeiro-Paciente , Supervisão de Enfermagem/normas , Relações Profissional-Família , Suécia , Recursos HumanosRESUMO
AIM: To describe and analyse the nursing students' experiences of the effects of process-orientated group supervision. BACKGROUND: There is a need to promote the development of the nursing student's professional identity and preparedness to act as well as to provide the opportunity for reflection and setting up a group supervision programme. METHOD: This paper is an in-depth study using both quantitative and qualitative methodologies. An open-ended interview form including 24 items and four open-ended questions was used and 80 nursing students answered a questionnaire. The data were analysed by a factor analysis with varimax rotation and by open coding. FINDINGS: The three analysis factors were labelled: 'Increased patient attentiveness', Increased empathy ability', and 'Increased insight and security'. From the findings of the qualitative analysis two main categories emerged: 'Increased ability to communicate' and 'Personal growth'. CONCLUSIONS: The findings of this study suggest that there is an association between the effects of group supervision and the nursing students' development of a nurse identity.
Assuntos
Bacharelado em Enfermagem/organização & administração , Processos Grupais , Supervisão de Enfermagem/organização & administração , Estudantes de Enfermagem/psicologia , Atitude do Pessoal de Saúde , Humanos , Pesquisa em Educação em Enfermagem , Pesquisa Metodológica em Enfermagem , Competência Profissional , Autoimagem , Inquéritos e QuestionáriosRESUMO
Transforming growth factor-beta (TGF-beta) has been known to be involved in the pathogenesis of various kidney diseases. TGF-beta is also a potent immunosuppressor that has been shown to be induced after allogeneic transplantation. We have studied the distribution of immunoreactive TGF-beta proteins in different compartments of 21 allogeneic transplanted kidneys that had been rejected through acute (eight interstitial or six vascular) and chronic (seven vascular) processes. This distribution was compared with that in seven non-rejected transplanted and five non-transplanted kidneys with intact morphology. There were no obvious differences between the three groups of rejected grafts and the transplanted non-rejected group for the expression of TGF-beta s. A major difference was seen between transplanted kidneys, which exhibited clearly positive TGF-beta and LTBP1 (latent TGF-beta binding protein) immunoreactivities, and the non-transplanted kidneys. The non-transplanted kidneys showed only very weak or no immunoreactivity for these proteins. The morphologically intact non-rejected grafts showed a significantly increased immunoreactivity compared with the non-transplanted kidneys. When the transplanted kidneys were classified into two groups (i.e. with or without diabetes mellitus) and compared with regard to the expression of all TGF-beta s, no difference was found. Thus, transplantation was the most important predictor for expression of TGF-beta s and LTBP1, and the largest expression increase in the allografts occurred in the interstitium, followed by the glomeruli and blood vessels. Tubuli and lymphocyte aggregates stained only faintly. The results imply that TGF-beta is induced rapidly after kidney transplantation. This induction can suppress immunoreactivation, but concomitantly promotes changes such as arteriosclerosis and fibrosis associated with rejection.
Assuntos
Transplante de Rim/imunologia , Fator de Crescimento Transformador beta/imunologia , Humanos , Glomérulos Renais/química , Túbulos Renais/química , Artéria Renal/química , Veias Renais/químicaRESUMO
Hemorphins are endogenous opioids derived by enzymatic degradation of hemoglobin, a protein released in blood plasma during long distance running. We examined levels of beta-endorphin and the heptapeptide hemorphin-7, in heparinized venous blood plasma from 15 sedentary controls (8 males, 7 females) and from 15 age- and sex-matched marathon runners at baseline and after running 42 km or 21 km. Baseline levels of beta-endorphin (range 0.2-4.3 fmol/ml) were neither dependent upon weight, body mass index weight/height, running status nor sex. Baseline levels of hemorphin-7 (range 0.2-6.9 pmol/ml) were lower in women (P < 0.04) and covariated positively with body weight (P = 0.06), explaining lower levels in runners by their lower body weight. Covariation with body mass index was positive, but not significant (P = 0.10), however, here the dependence upon sex appeared stronger (P = 0.014). Running induced significant and correlated increases in hemorphin-7 and beta-endorphin (r = 0.74; P < 0.002), possibly indicating a functional relationship between these two peptides.
Assuntos
Hemoglobinas/metabolismo , Neurotransmissores/sangue , Fragmentos de Peptídeos/metabolismo , Corrida/fisiologia , beta-Endorfina/sangue , Adulto , Sequência de Aminoácidos , Cromatografia em Gel , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Radioimunoensaio/métodos , Caracteres SexuaisRESUMO
Human ACE obtained from different tissues and body fluids was assayed with regard to degradative action on tachykinins and various opioid peptides. Substance P (1-9) was easily cleaved, whereas substance P and neurokinin A seemed stable against ACE activity. However, endopeptidase-24.11 easily degraded both of these amidated peptides. When the same peptides were assayed as potential inhibitors of the hydrolysis of hippuryl-His-Leu (specific substrate for ACE activity), substance P and its (1-9) fragment were equally potent, whereas neurokinin A was inactive. The beta-casomorphins, beta-casein derived opioid peptides, with a proline residue at their C-terminus also showed inhibitory action on ACE activity, without being cleaved by the enzyme. These results indicate a modulatory action of these peptides. No differences between ACE originating from different tissues or body fluids could be demonstrated in this regard.
Assuntos
Encéfalo/metabolismo , Pulmão/metabolismo , Neuropeptídeos/metabolismo , Peptidil Dipeptidase A/metabolismo , Sequência de Aminoácidos , Cromatografia Líquida de Alta Pressão , Endotélio/enzimologia , Humanos , Espectrometria de Massas , Dados de Sequência Molecular , Neprilisina/metabolismo , Neurônios/enzimologia , Peptidil Dipeptidase A/sangue , Peptidil Dipeptidase A/líquido cefalorraquidianoRESUMO
The hemorphins are opioid active peptides, which are enzymatically released from the beta-chain of hemoglobin. In this paper we report an inhibitory effect of these peptides on angiotensin converting enzyme (ACE) activity, known to be involved in blood pressure regulation. The hemorphins were found to be quite stable in tissue extracts containing ACE, and their importance as naturally occurring ACE inhibitors is discussed.
Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Hemoglobinas/farmacologia , Fragmentos de Peptídeos/farmacologia , Sequência de Aminoácidos , Pressão Sanguínea/fisiologia , Cromatografia Líquida de Alta Pressão , Ácido Edético/farmacologia , Hemoglobinas/isolamento & purificação , Hemoglobinas/metabolismo , Humanos , Pulmão/enzimologia , Dados de Sequência Molecular , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/metabolismo , Peptidil Dipeptidase A/metabolismoRESUMO
Three different molecular forms of angiotensin converting enzyme (ACE) (approximately Mr 150,000, 80,000 and 40,000, respectively), have been recovered from human cerebrospinal fluid. All three enzymes were inhibited by captopril and enalapril and their activity was potentiated by chloride ions. They were capable of degrading Leu-enkephalin-Arg6 and substance -P, but gave no conversion of neurokinin A. In all these aspects, the CSF enzymes were identical with the human pulmonary enzyme. The Mr 40,000 form of ACE is the smallest active form of the enzyme hitherto reported and is likely to represent a fragment of the C-terminal part of native ACE, where its active center is located.
Assuntos
Peptidil Dipeptidase A/líquido cefalorraquidiano , Sequência de Aminoácidos , Inibidores da Enzima Conversora de Angiotensina , Captopril/farmacologia , Cloretos/farmacologia , Cromatografia Líquida de Alta Pressão , Enalapril/farmacologia , Encefalina Leucina/análogos & derivados , Encefalina Leucina/metabolismo , Humanos , Dados de Sequência Molecular , Peso Molecular , Neurocinina A/metabolismo , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Radioimunoensaio , Substância P/metabolismoRESUMO
The metabolism of enkephalin peptides was studied in human cerebrospinal fluid. The degradation rates of (Leu)-enkephalin and (Leu)-enkephalin-Arg6 were compared and the latter was degraded at a 10-fold higher rate. The major enzyme activity was investigated by Mr determination and inhibition experiments, showing marked similarity with angiotensin-converting enzyme.