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1.
Int J Cosmet Sci ; 31(3): 193-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19563587

RESUMO

The assessment of odours and in particular of human axillary odour is an integral part of the research and development of deodorant and anti-perspirant products. One method to perform odour assessment is the odour evaluation that is carried out by experts, designated as odour testers or sniffers. Product development decisions are therefore based on human assessment. As for every scientific measurement, the influencing factors need to be standardized or regularly calibrated as effectively as possible for reasons of quality assurance. We therefore developed a screening and training concept aiming to examine the general suitability of odour testers by determining the individual odour sensitivity for relevant odours. This newly developed method is based on the national and international standards and guidelines EN 13725:2003, VDI 3882 sheet 1 and ASTM-1207. Suitable odour testers are subsequently trained to correlate their individual odour intensity perception with an intensity calibration scale in order to achieve reproducible results. Training sessions held on a regular basis help to achieve a greater homology in the response of an existing panel. Our established screening and training protocol has already been successfully put into practice and is also subject to permanent improvement with regard to practical requirements.


Assuntos
Cosméticos , Capacitação em Serviço , Odorantes , Humanos
2.
Cell ; 83(5): 793-802, 1995 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-8521496

RESUMO

The 60 kDa tumor necrosis factor receptor (TNFR60) is regarded as the major signal transducer of TNF-induced cellular responses, whereas the signal capacity and role of the 80 kDa TNFR (TNFR80) remain largely undefined. We show here that the transmembrane form of TNF is superior to soluble TNF in activating TNFR80 in various systems such as T cell activation, thymocyte proliferation, and granulocyte/macrophage colony-stimulating factor production. Intriguingly, activation of TNFR80 by membrane TNF can lead to qualitatively different TNF responses such as rendering resistant tumor cells sensitive to TNF-mediated cytotoxicity. This study demonstrates that the diversity of TNF effects can be controlled through the differential sensitivity of TNFR80 for the two forms of TNF and suggests an important physiological role for TNFR80 in local inflammatory responses.


Assuntos
Receptores do Fator de Necrose Tumoral/imunologia , Transdução de Sinais/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Anticorpos Monoclonais , Sequência de Bases , Células CHO , Divisão Celular , Membrana Celular , Células Cultivadas , Técnicas de Cocultura , Cricetinae , Citotoxicidade Imunológica/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Antígenos HLA-DR/biossíntese , Humanos , Cinética , Ligantes , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Dados de Sequência Molecular , Receptores do Fator de Necrose Tumoral/agonistas , Receptores do Fator de Necrose Tumoral/metabolismo , Solubilidade , Linfócitos T/imunologia , Timo/citologia , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/química , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
3.
J Exp Med ; 166(6): 1788-97, 1987 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-2824656

RESUMO

The regulatory action of activators for protein kinase C on the specific binding capacity for recombinant human tumor necrosis factor alpha (TNF-alpha) was studied on various human cell lines. Phorbol myristate acetate (PMA) and oleyl acetyl glycerol (OAG) both are able to rapidly downregulate TNF-binding capacity of normal and malignant cells derived from various tissues. As PMA treatment did not enhance internalization of TNF-alpha-receptor complexes at 37 degrees C, and since OAG was able to downregulate TNF-binding capacity under conditions where internalization and shedding of receptor protein are prevented, we conclude that protein kinase C controls ligand affinity of the TNF-receptor protein, possibly via direct phosphorylation. Protein kinase C triggered downregulation of TNF-alpha-binding capacity concomitantly resulted in reduction of TNF-alpha sensitivity, as revealed from decreased cytotoxic action of TNF-alpha on L 929 cells and from inhibition of TNF-alpha-mediated enhancement of HLA class II antigen expression in Colo 205 cells. Restoration of TNF-binding capacity upon abrogation of protein kinase C stimulation leads to full recovery of TNF responsiveness, further supporting the close linkage of TNF-receptor expression and TNF sensitivity. These data suggest that regulation of TNF-binding capacity by protein kinase C is one of the cellular control mechanisms of TNF responsiveness.


Assuntos
Proteína Quinase C/fisiologia , Receptores de Superfície Celular/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Sobrevivência Celular , Células Cultivadas , Endocitose , Humanos , Proteína Quinase C/antagonistas & inibidores , Receptores do Fator de Necrose Tumoral , Proteínas Recombinantes/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/toxicidade
4.
Biochem Biophys Res Commun ; 141(2): 855-60, 1986 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-3026394

RESUMO

Tumor necrosis factor membrane receptors are rapidly down-regulated upon treatment of activated T lymphocytes with various activators of protein kinase C. Loss of binding-capacity was half maximal after 2 min. incubation in 10 ng/ml of phorbol 12-myristate 13-acetate. A similar modulation could be induced with either the calcium ionophore A 23187 or the protein kinase C activator 1-oleyl-2-acetyl glycerol, whereas 1,2-diolein and dibutyryl cAMP were ineffective. Protein kinase C inhibitor H7 antagonizes the phorbol ester-induced TNF receptor modulation. These data suggest an important role of protein kinase C in the control of TNF responsiveness by regulation of TNF binding-capacity possibly via direct phosphorylation of specific receptor proteins.


Assuntos
Glicoproteínas/metabolismo , Proteína Quinase C/metabolismo , Receptores de Superfície Celular/metabolismo , Linfócitos T/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina , Calcimicina/farmacologia , Células Cultivadas , Diglicerídeos/farmacologia , Humanos , Isoquinolinas/farmacologia , Ativação Linfocitária , Piperazinas/farmacologia , Proteína Quinase C/antagonistas & inibidores , Receptores do Fator de Necrose Tumoral , Linfócitos T/efeitos dos fármacos , Fator de Necrose Tumoral alfa
5.
Immunobiology ; 169(5): 472-85, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2864311

RESUMO

In order to study the postnatal development of functional T cell subsets in the mouse, a mitogen-driven limiting dilution culture system was used for a precursor frequency analysis of proliferating, of cytolytic and of IL 2-producing T cells, respectively, present in spleen and thymus of mice from neonatal to adult age. In adult mice, the majority (up to 100%) of splenic T cells was capable to respond to Concanavalin A. In contrast, an up to tenfold lower frequency of mitogen-reactive precursors was found within positively selected Thy-1+ spleen cells of neonatal mice. Within this fraction of Con A reactive neonatal T cells, there was an apparent imbalance in the CTLp/PTLp ratio within the first to second week after birth. Accordingly, significant numbers of immunocompetent precursors of HTLp were detected in the spleen shortly after birth, while the vast majority of CTLp developed later on. This differential development of CTLp and PTLp was not seen with thymocytes of the same mice, where from the age of two to three days on up to the adult age the frequency of both CTLp and PTLp remained largely unchanged. Analysis of the Lyt-antigen expression, in addition, revealed phenotypical differences between neonatal and adult Thy-1+ spleen cells, such that Lyt-2 antigen density but not the proportion of Lyt-2 positive T cells, was considerably lower in newborn mice. An age related increase in both Lyt-2 antigen density and CTLp frequency was parallelled by the rapid increase in the total number of splenic T cells during the second and third postnatal week, reaching 60-70% of adult values. At this time, a normalisation of the CTLp/PTLp ratio at approximately 0.4 had occurred.


Assuntos
Linfócitos T/imunologia , Fatores Etários , Animais , Animais Recém-Nascidos/imunologia , Anticorpos Monoclonais , Antígenos de Diferenciação de Linfócitos T , Antígenos Ly/análise , Antígenos de Superfície/análise , Diferenciação Celular , Citotoxicidade Imunológica , Interleucina-2/biossíntese , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos CBA , Baço/citologia , Linfócitos T/classificação , Linfócitos T/citologia , Linfócitos T Citotóxicos/imunologia , Antígenos Thy-1 , Timo/citologia
6.
J Sch Health ; 46(2): 81-5, 1976 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1044931

RESUMO

Although certain exceptions may be noted with respect to sex and type of school, generally lower socioeconomic students obtained lower mean scores on the knowledge and attitude sections of the survey instrument than their counterparts from the higher economic strata. Disadvantaged children from lower socioeconomic levels are reared in an atmosphere hardly conducive to study. Their homes are overcrowded; the children are often hungry, obtain insufficent rest, and possess little interest or motivation for the future--they just live for today. The lower socioeconomic child suffers most when he comes to school. His experiences in living have not prepared him for the demands of the typical school. Shaped by his environment, seeing himself as a person of little worth, he is called upon to conform and communicate. His value system that was bred in deprivation shows sharp contrast to the established "middle class" value system held by the school. Furthermore, disadvantaged children enter school with habits and attitudes that may conflict with many of the traditional modes of teaching. They have had few opportunities to learn the relationship between effort and achievement or to observe that learning has its own reward. Educators have a responsibility to provide the best type of family life education program to meet the needs of all youth. Innovative and challenging ways must be found to make family life education programs relevant to all socioeconomic strata. It would appear essential that educators should possess a thorough knowledge of the economic, social, and cultural conditions that exist in the area in which the educational process is to be conducted.


Assuntos
Educação Sexual , Estudantes , Atitude , Criança , Avaliação Educacional , Características da Família , Humanos , Illinois , Masculino , Autoimagem , Fatores Sexuais , Fatores Socioeconômicos
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