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1.
BMC Geriatr ; 20(1): 199, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32517653

RESUMO

BACKGROUND: The combined effect of sarcopenia and obesity, i.e., sarcopenic obesity, has been associated with disability and worse outcomes in older adults, but results are conflicting. The objectives of this study were to describe the prevalence of sarcopenic obesity (SO) in older adults, and to examine how the risk of mortality is associated with SO and its various components. METHODS: Data were obtained from two Swedish population studies, the Gothenburg H70 Birth Cohort Studies of 521 women and men at the age of 75, and the Uppsala Longitudinal Study of Adult Men (ULSAM), which included 288 men aged 87 years. Sarcopenia was defined using the recently updated EWGSOP2 definition. Obesity was defined by any of three established definitions: body mass index ≥30 kg/m2, fat mass > 30%/ > 42% or waist circumference ≥ 88 cm/≥102 cm for women and men, respectively. The Kaplan-Meier survival curve and the Cox proportional hazard model were used for 10-year and 4-year survival analyses in the H70 and ULSAM cohorts, respectively. RESULTS: SO was observed in 4% of the women and 11% of the men in the H70 cohort, and in 10% of the ULSAM male cohort. The 75-year-old women with SO had a higher risk (HR 3.25, 95% confidence interval (1.2-8.9)) of dying within 10 years compared to those with a "normal" phenotype. A potential similar association with mortality among the 75-year-old men was not statistically significant. In the older men aged 87 years, obesity was associated with increased survival. CONCLUSIONS: SO was observed in 4-11% of community-dwelling older adults. In 75-year-old women SO appeared to associate with an increased risk of dying within 10 years. In 87-year-old men, the results indicated that obesity without sarcopenia was related to a survival benefit over a four-year period.


Assuntos
Sarcopenia , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Humanos , Estudos Longitudinais , Masculino , Obesidade/diagnóstico , Obesidade/epidemiologia , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Suécia/epidemiologia
2.
J Exp Med ; 155(1): 140-54, 1982 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-6976411

RESUMO

Large cortical thymocytes from C57BL/6-Tla(a) mice have been prepared rapidly and in high yield by a combination of centrifugal elutriation and differential binding to peanut agglutinin (PNA)-coated plates. The cells in these lymphoblast-rich fractions were clearly distinct from the majority of thymocytes, with up to 70 percent in the S or G(2) + M phases of the cell cycle and an average rate of [(35)S]methionine incorporation per cell up to 20 times higher than that of the majority population. The populations of cells resolved in this fractionation were characterized by monitoring their rates of synthesis of specific glycoproteins, thymus- leukemia antigen (TL) and the Lyt-2, Lyt-3 complex (Lyt-2/3), relative to their total protein synthesis. Cells that bound to PNA synthesized high levels of Lyt-2/3, consistent with their identification as cortical thymocytes. Those that failed to bind made little or no Lyt-2/3, as expected for medullary cells, The fraction of dividing lymphoblasts that bound to PNA was enriched in cortical thymocyte precursors, including all the large cells detectably active in synthesizing Lyt-2. It differed sharply from the small cortical cells, however, in the synthesis of TL. Although both populations displayed abundant surface TL, the TL glycoprotein was produced actively in fractions containing dividing cells but made at a drastically reduced rate by the nondividing majority of cortical thymocytes. Thus, TL seems to be made at a narrowly circumscribed stage of early thymocyte development that is correlated with rapid proliferation. In most of the descendants of such blast cells, the TL glycoprotein is presumably retained on the cell surface as long as no substantial membrane turnover takes place. Ongoing TL synthesis may therefore serve as a marker for a unique developmental state which terminates rapidly in normal differentiation but may be extended by agents that give rise to TL(+) thymic lymphomas.


Assuntos
Antígenos de Neoplasias/imunologia , DNA/biossíntese , Glicoproteínas/imunologia , Ativação Linfocitária , Glicoproteínas de Membrana , Linfócitos T/imunologia , Animais , Antígenos Ly , Sítios de Ligação , Separação Celular , Transformação Celular Neoplásica , Feminino , Lectinas , Masculino , Metionina/metabolismo , Camundongos , Camundongos Endogâmicos A , Camundongos Endogâmicos C57BL , Aglutinina de Amendoim , Timo/imunologia
3.
J Exp Med ; 150(4): 777-91, 1979 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-315985

RESUMO

Thymus-leukemia (TL) antigens are expressed in murine lymphocytes under strict developmental regulation. To elucidate the molecular basis of TL expression, we have identified the molecular species that react with TL antiserum. At least three species can be resolved by metabolic radiolabeling of thymocytes and ASL1 leukemia cells, lysis, immune precipitation, and sodium dodecyl sulfate-polyacrylamide. After a brief incubation with [35S]methionine, the only radioactive molecule recognized by TL antiserum is a homogeneous species with an apparent Mr of 45,000 daltons. This molecule, 45K TL, includes high-mannose-type carbohydrate attached to a 45,000 dalton glycosidase-resistant backbone. In this form, 45K, it is never exposed on the cell surface. If pulse-labeled cells are further incubated with nonradioactive methionine before lysis, however, radioactivity disappears from the 45K TL species and appears in the slower migrating species 46K and 48K TL. Thus, 46K and 48K appear to represent products generated from the 45K TL precursor by posttranslational modification. These TL forms are displayed on the cell surface; they lack high-mannose carbohydrate but evidently include acidic complex-type carbohydrate. Normal thymocytes from Qa:Tla-negative mice lack not only the surface forms of TL but also the intracellular 45K TL form. Peripheral lymphoid cells of Qa:Tla-positive mice synthesize none of these TL species. But the TL antiserum, which contains Qa antibody, recognizes a distinct gene product in spleen and thymus of Qa-Tla-positive mice. In its pulse-labeled form, this molecule, which may represent Qa-1, has an apparent Mr of 44,000 daltons, and consists of a glycosidase-resistant polypeptide core of only 35,000 daltons linked to more high mannose carbohydrate than 45K TL.


Assuntos
Antígenos de Neoplasias/imunologia , Glicoproteínas/biossíntese , Leucemia Experimental/imunologia , Proteínas de Neoplasias/biossíntese , Linfócitos T/imunologia , Animais , Configuração de Carboidratos , Membrana Celular/metabolismo , Citoplasma/metabolismo , Glicoproteínas/metabolismo , Camundongos , Peso Molecular , Proteínas de Neoplasias/metabolismo , Timo/citologia
4.
J Exp Med ; 157(1): 365-70, 1983 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-6848621

RESUMO

We investigated the possibility that the Lyt-2 molecules made by uncloned mouse T lymphocytes would show variable primary structures like those of immunoglobulins. Newly synthesized Lyt-2/3 complexes were found to include only two major components, both discrete glycoproteins with apparent molecular weights of 31,000 (31 K) and 35,000 (35 K). When products of Lyt-2.1 and Lyt-2.2 thymocytes were compared by two-dimensional nonequilibrium pH gradient electrophoresis and sodium dodecyl sulfate polyacrylamide gel electrophoresis, the isoelectric points of the 35 K molecules were different; thus, the 35 K component was likely to be encoded by the Lyt-2 locus itself. However, the 35 K molecules made by any one genotype were homogeneous in charge as well as in size. The homogeneity was obscured rapidly by post-translational modification. Most strikingly, within 30 min of initial synthesis, these processing events generated the conspicuous array of microheterogeneous products that form the "38 K" component of cell-surface Lyt-2/3.


Assuntos
Glicoproteínas/biossíntese , Glicoproteínas/imunologia , Animais , Antígenos Ly , Ponto Isoelétrico , Substâncias Macromoleculares , Camundongos , Peso Molecular , Processamento de Proteína Pós-Traducional
5.
J Exp Med ; 179(3): 931-42, 1994 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8113685

RESUMO

Elevation of cAMP can cause gene-specific inhibition of interleukin 2 (IL-2) expression. To investigate the mechanism of this effect, we have combined electrophoretic mobility shift assays and in vivo genomic footprinting to assess both the availability of putative IL-2 transcription factors in forskolin-treated cells and the functional capacity of these factors to engage their sites in vivo. All observed effects of forskolin depended upon protein kinase A, for they were blocked by introduction of a dominant negative mutant subunit of protein kinase A. In the EL4.E1 cell line, we report specific inhibitory effects of cAMP elevation both on NF-kappa B/Rel family factors binding at -200 bp, and on a novel, biochemically distinct "TGGGC" factor binding at -225 bp with respect to the IL-2 transcriptional start site. Neither NF-AT nor AP-1 binding activities are detectably inhibited in gel mobility shift assays. Elevation of cAMP inhibits NF-kappa B activity with delayed kinetics in association with a delayed inhibition of IL-2 RNA accumulation. Activation of cells in the presence of forskolin prevents the maintenance of stable protein-DNA interactions in vivo, not only at the NF-kappa B and TGGGC sites of the IL-2 enhancer, but also at the NF-AT, AP-1, and other sites. This result, and similar results in cyclosporin A-treated cells, imply that individual IL-2 transcription factors cannot stably bind their target sequences in vivo without coengagement of all other distinct factors at neighboring sites. It is proposed that nonhierarchical, cooperative enhancement of binding is a structural basis of combinatorial transcription factor action at the IL-2 locus.


Assuntos
Colforsina/farmacologia , AMP Cíclico/metabolismo , Proteínas de Ligação a DNA/metabolismo , Interleucina-2/biossíntese , Fatores de Transcrição/metabolismo , Transcrição Gênica , Sequência de Bases , Sítios de Ligação , Calcimicina/farmacologia , Linhagem Celular , Proteínas Quinases Dependentes de AMP Cíclico/biossíntese , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ciclosporina/farmacologia , Proteínas de Ligação a DNA/isolamento & purificação , Expressão Gênica/efeitos dos fármacos , Interleucina-2/análise , Interleucina-2/isolamento & purificação , Cinética , NF-kappa B/metabolismo , RNA Mensageiro/biossíntese , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Timoma , Neoplasias do Timo , Fatores de Transcrição/antagonistas & inibidores , Transcrição Gênica/efeitos dos fármacos , Transfecção , Células Tumorais Cultivadas
6.
J Exp Med ; 161(5): 1048-62, 1985 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-3921650

RESUMO

We have tested the dividing cells in the mouse thymus for expression of interleukin 2 (IL-2) receptors (IL-2-R) using the rat monoclonal antibody 7D4. A discrete subpopulation of the lymphoblasts clearly expressed IL-2-R at levels comparable to those on mitogen-activated peripheral T cells. This subpopulation, however, represented a small minority of the proliferating cells. IL-2-R-bearing cells were depleted from the PNA+ (peanut agglutinin) lymphoblast population, which contains the direct precursors of most of the cells in the thymus. The majority of receptor-bearing cells were found in the PNA- lymphoblast population, where they constituted only approximately 12% of the cells. Thus, virtually all the PNA+ and most of the PNA- blast cells were in cycle without detectable IL-2-R expression. This indicates that they were not dividing in response to IL-2, and implies that they were not dividing in response to antigen, but rather to novel thymus-specific mitogenic stimuli. On the other hand, the proliferating cells that do express IL-2-R were enriched 4-5-fold in the rapidly growing neonatal thymus, suggesting that they may also play a key role in T cell development.


Assuntos
Ativação Linfocitária , Receptores de Antígenos de Linfócitos T/análise , Receptores Imunológicos/análise , Células-Tronco/metabolismo , Timo/citologia , Animais , Animais Recém-Nascidos/imunologia , Linhagem Celular , Separação Celular/métodos , Centrifugação , Feminino , Lectinas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Aglutinina de Amendoim , Fenótipo , Receptores de Antígenos de Linfócitos T/biossíntese , Receptores de Antígenos de Linfócitos T/fisiologia , Receptores Imunológicos/biossíntese , Receptores Imunológicos/fisiologia , Receptores de Interleucina-2 , Células-Tronco/classificação , Células-Tronco/imunologia , Timo/imunologia , Timo/metabolismo
7.
Curr Opin Genet Dev ; 10(4): 370-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10889068

RESUMO

B and T lymphocytes differentiate from multipotent precursors through distinct specification and commitment steps. New findings on the unique role of Pax5 in B-lineage commitment, dichotomous action of Notch signaling in B versus T cell development, and the gene expression changes comprising T-lineage specification and commitment now illuminate this process.


Assuntos
Linfócitos B/citologia , Células-Tronco Hematopoéticas/citologia , Linfócitos T/citologia , Fatores de Transcrição , Animais , Diferenciação Celular , Linhagem da Célula , Proteínas de Ligação a DNA/metabolismo , Humanos , Proteínas de Membrana/fisiologia , Fator de Transcrição PAX5 , Proteínas/metabolismo , Receptores Notch , Timo/citologia , Transativadores/metabolismo
8.
J Hum Nutr Diet ; 21(3): 239-47, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18477179

RESUMO

BACKGROUND: According to the Council of Europe, clinical dietitians should assume a more central role in nutritional support. The aim of this study was to assess the opinions among doctors, nurses and clinical dietitians regarding the use of clinical dietitians' expertise in the hospital units and, further, to assess whether the presence of clinical dietitians in hospital departments influenced doctors and nurses focus on clinical nutrition. METHODS: A questionnaire about the use of clinical nutrition was mailed to 6000 doctors and 6000 nurses working in hospital units where undernutrition is documented to be common, as well as to 678 clinical dietitians working in Scandinavian hospitals. RESULTS: The response rate of clinical dietitians, nurses and doctors were 53%, 46% and 29%, respectively. Nurses and doctors who saw clinical dietitians often found it less difficult to identify undernourished patients and found that insight into the importance of adequate nutrition was better than those who saw clinical dietitians seldom. Clinical nutrition had a higher priority in units with frequent visits by clinical dietitians. CONCLUSIONS: The present study shows that doctors and nurses on wards with greater access to clinical dietitians had better focus on clinical nutrition.


Assuntos
Dietética/normas , Desnutrição/terapia , Recursos Humanos de Enfermagem Hospitalar/psicologia , Apoio Nutricional/normas , Equipe de Assistência ao Paciente , Médicos/psicologia , Adulto , Feminino , Humanos , Masculino , Avaliação Nutricional , Inquéritos e Questionários
9.
Curr Opin Immunol ; 6(2): 257-65, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7516664

RESUMO

The processes known as positive and negative selection that determine the fate of T and B cells depend on finely tuned interactions between the T-cell receptor complex, CD4 or CD8 co-receptors, and a peptide-MHC complex. New work indicates that the avidity of this interaction is critical in the determination of its outcome. The effects of these interactions on developing thymocytes are also a function of the unique activation properties with which thymocytes are programmed just before they undergo selection.


Assuntos
Linfócitos T/citologia , Timo/citologia , Timo/crescimento & desenvolvimento , Animais , Antígenos de Superfície/fisiologia , Comunicação Celular/fisiologia , Ligantes , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2 , Receptores de Antígenos de Linfócitos T/fisiologia , Receptores de Superfície Celular/fisiologia , Transdução de Sinais , Receptor fas
10.
Mol Cell Biol ; 13(1): 228-37, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8417328

RESUMO

At least three stages in the intrathymic development of pre-T cells are demarcated by differences in the competence to express the interleukin-2 (IL-2) gene as an acute response to stimulation. IL-2 inducibility appears to be acquired relatively early, prior to T-cell receptor (TcR) gene rearrangement. It is then abrogated during the stage when cells are subject to positive and negative selection, i.e., the fate determination processes that select cells for maturation or death. IL-2 inducibility finally reappears in mature classes of thymocytes that have undergone positive selection. To provide a basis for a molecular explanation of these developmental transitions, we have examined the representation in different thymocyte subsets of a set of DNA-binding proteins implicated in IL-2 gene regulation. As the DNA-binding activities of many factors are elicited only by inductive stimuli, the cells were cultured in the presence or absence of the calcium ionophore A23187 and phorbol ester. Our results separate these factors into four regulatory classes: (i) constitutive factors, such as Oct-1 and probably Sp1, that are expressed in thymocytes at all stages; (ii) inducible factors, such as NF-kappa B and complexes binding to the region of a CD28 response element, that can be activated in all thymocytes, including those cells (CD4+ CD8+ TcRlow) that can undergo selection; (iii) inducible factors, such as NF-AT and AP-1, that can be activated in mature (CD4+ CD8- TcRhigh) and immature (CD4- CD8- TcR-) thymocytes alike but not in the transitional stages when the cells (CD4+ CD8+ TcRlow) are subject to selection; and (iv) a factor containing CREB, which can be activated in thymocytes of all developmental stages by culture but does not require specific induction. These results verify that inducible transcription factors are targets of intrathymic developmental change. They also identify NF-AT and AP-1 as factors that are particularly sensitive to the mechanism altering thymocyte responses during the stages when thymocytes may undergo positive and negative selection.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-2/farmacologia , Subpopulações de Linfócitos T/fisiologia , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Diferenciação Celular , Núcleo Celular/fisiologia , Células Cultivadas , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos/química , Proteínas Proto-Oncogênicas c-jun/metabolismo , Subpopulações de Linfócitos T/citologia , Timo/citologia
11.
Mol Cell Biol ; 10(12): 6325-34, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2174106

RESUMO

The macrophage-derived cytokine interleukin-1 (IL-1) can provide a second signal with antigen to elicit production of interleukin-2 (IL-2) by helper T cells. The pathway(s) involved remains controversial, with protein kinase C and cyclic AMP (cAMP) invoked as possible second messengers. In the murine thymoma EL4.E1, IL-1 could synergize with the phosphoinositide pathway, because the cells made higher levels of IL-2 in the presence of IL-1 than could be induced by phorbol ester plus calcium ionophore alone. IL-1 is unlikely to act through a sustained increase in cAMP in these cells because it did not raise cAMP levels detectably and because IL-1 and forskolin had opposite effects on IL-2 gene expression. Inducible expression of a transfected reporter gene linked to a cloned fragment of the murine IL-2 gene promoter was initially increased by IL-1 costimulation, implying that IL-1 can increase the rate of transcription of IL-2. The minimal promoter elements required for iL-1 responsiveness were located within 321 bp of the IL-2 RNA cap site, and further upstream sequences to -2800 did not modify this response. IL-1 costimulation resulted in enhanced activity of both an inducible NF-kappa B-like factor and one of two distinct AP-1-like factors that bind to IL-2 regulatory sequences. Neither was induced, however, by IL-1 alone. Another AP-1-like factor and NFAT-1, while inducible in other cell types, were expressed constitutively in the EL4.E1 cells and were unaffected by IL-1. These results are discussed in terms of the combinatorial logic of IL-2 gene expression.


Assuntos
Expressão Gênica/efeitos dos fármacos , Interleucina-1/farmacologia , Interleucina-2/genética , Fosfatidilinositóis/metabolismo , Sistemas do Segundo Mensageiro , Transdução de Sinais , Acetato de Tetradecanoilforbol/farmacologia , Transcrição Gênica/efeitos dos fármacos , Animais , Sequência de Bases , Calcimicina/farmacologia , Linhagem Celular , Cloranfenicol O-Acetiltransferase/biossíntese , Cloranfenicol O-Acetiltransferase/genética , Sinergismo Farmacológico , Interleucina-2/biossíntese , Camundongos , Dados de Sequência Molecular , NF-kappa B/genética , Sondas de Oligonucleotídeos , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes/farmacologia , Sistemas do Segundo Mensageiro/efeitos dos fármacos , Transfecção
12.
Mol Cell Biol ; 12(4): 1515-27, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1312665

RESUMO

We describe conditions under which exogenous DNA templates can be introduced for transient expression into primary murine T lymphocytes. T cells at various stages of development, including concanavalin A-activated splenic T cells, immature pre-T cells, and even small cortical thymocytes, could be successfully transfected. A variety of model DNA constructs were compared in which different viral promoter regions were used to drive expression of the chloramphenicol acetyltransferase (CAT) reporter gene. All showed enhanced expression in cells that had been acutely stimulated with the Ca2+ ionophore A23187 and phorbol ester as chemical proxies for T-cell receptor-mediated signals. In addition, splenocytes but not thymocytes required prior treatment with a mitogen and interleukin-2 in order to express these constructs, implying that even postmitotic thymocytes may be held in a quasiactivated state. A most striking result was the finding that the viral regulatory sequences in the Rous sarcoma virus long terminal repeat and the simian virus 40 early region were subject to sharply differential regulation, with a rank order that changed depending on the developmental stage of the T cells. The most immature thymic blasts and several lymphoma cell lines expressed the pRSV-Cat and pSV2-Cat constructs similarly, but cortical thymocytes exhibited a strong preference for pSV2-Cat. Splenic concanavalin A-stimulated blasts, on the other hand, slightly preferred pRSV-Cat, a tendency which became exaggerated in factor-dependent T-cell lines. The ratio of pRSV-Cat to pSV2-Cat expression varied according to cell type by as much as 500-fold. These results argue against a trivial linkage of promoter preference to cell cycle status but instead provide evidence that activation of T cells at distinct stages of differentiation results in the expression of different ensembles of nuclear regulatory proteins. In contrast to the simian virus 40 and Rous sarcoma virus promoter regions, the long terminal repeats of the retroviruses mink cell focus-forming virus and Akv were expressed well in all primary T-lineage cells. Thus, they represent excellent model promoters for engineering developmental stage-independent expression of exogenous genes in murine T cells.


Assuntos
Regulação da Expressão Gênica , Genes Virais/genética , Ativação Linfocitária/genética , Regiões Promotoras Genéticas/genética , Transfecção , Animais , Vírus do Sarcoma Aviário/genética , Células Cultivadas , Cloranfenicol O-Acetiltransferase/genética , Substâncias de Crescimento/metabolismo , Humanos , Técnicas In Vitro , Interleucina-2/metabolismo , Vírus da Leucemia Murina/genética , Camundongos , Vírus 40 dos Símios/genética , Baço/citologia , Subpopulações de Linfócitos T/metabolismo , Timo/citologia
13.
Mol Cell Biol ; 14(3): 2159-69, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8114746

RESUMO

Interleukin-2 (IL-2) transcription is developmentally restricted to T cells and physiologically dependent on specific stimuli such as antigen recognition. Prior studies have shown that this stringent two-tiered regulation is mediated through a transcriptional promoter/enhancer DNA segment which is composed of diverse recognition elements. Factors binding to some of these elements are present constitutively in many cell types, while others are signal dependent, T cell specific, or both. This raises several questions about the molecular mechanism by which IL-2 expression is regulated. Is the developmental commitment of T cells reflected molecularly by stable interaction between available factors and the IL-2 enhancer prior to signal-dependent induction? At which level, factor binding to DNA or factor activity once bound, are individual regulatory elements within the native enhancer regulated? By what mechanism is developmental and physiological specificity enforced, given the participation of many relatively nonspecific elements? To answer these questions, we have used in vivo footprinting to determine and compare patterns of protein-DNA interactions at the native IL-2 locus in cell environments, including EL4 T-lymphoma cells and 32D clone 5 premast cells, which express differing subsets of IL-2 DNA-binding factors. We also used the immunosuppressant cyclosporin A as a pharmacological agent to further dissect the roles played by cyclosporin A-sensitive factors in the assembly and maintenance of protein-DNA complexes. Occupancy of all site types was observed exclusively in T cells and then only upon excitation of signal transduction pathways. This was true even though partially overlapping subsets of IL-2-binding activities were shown to be present in 32D clone 5 premast cells. This observation was especially striking in 32D cells because, upon signal stimulation, they mobilized a substantial set of IL-2 DNA-binding activities, as measured by in vitro assays using nuclear extracts. We conclude that binding activities of all classes fail to stably occupy their cognate sites in IL-2, except following activation of T cells, and that specificity of IL-2 transcription is enforced at the level of chromosomal occupancy, which appears to be an all-or-nothing phenomenon.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Interleucina-2/genética , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Ciclosporina/farmacologia , Elementos Facilitadores Genéticos , Substâncias Macromoleculares , Camundongos , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos/química , Regiões Promotoras Genéticas , RNA Mensageiro/genética , Linfócitos T/fisiologia
14.
J Nutr Health Aging ; 11(6): 466-73, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17985061

RESUMO

OBJECTIVE: The aim of this study was to assess social disparities in food choices and diet quality in a population of 70-year old Swedes. DESIGN: Cross-sectional study among participants in the 2000 Gerontological and Geriatric Population Studies in Goteborg. PARTICIPANTS: A representative population of men (n=233) and women (n=321) from Goteborg, a city on the south western coast of Sweden. METHODS: One hour diet history interviews were performed and 35 specific foods and food groups were identified; in addition a diet quality index (DQI) was calculated. Differences in food choices and diet quality scores were tested across educational and socio-economic index categories (SEI). RESULTS: Men with higher education and SEI had higher diet quality scores than those with lower socio-economic status, while no differences in DQI were noted in women. Further analysis of women based on their husband's occupational group also yielded no differences in diet quality. When studying individual foods, socio-economic differences were observed in women and men. CONCLUSIONS: Selection of food varies by education and occupational status in both sexes although socio-economic disparities in diet quality were observed in men only.


Assuntos
Dieta/normas , Escolaridade , Preferências Alimentares/psicologia , Inquéritos Nutricionais , Atividades Cotidianas , Idoso , Intervalos de Confiança , Estudos Transversais , Dieta/psicologia , Comportamento Alimentar , Feminino , Humanos , Masculino , Razão de Chances , Distribuição por Sexo , Fatores Socioeconômicos , Suécia
16.
J Nutr Health Aging ; 21(7): 811-818, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28717811

RESUMO

OBJECTIVES: We examined if individually-adapted nutritional counselling could prevent > 5% weight loss among elderly patients 3 months after discharge from a rehabilitation institution. In addition we assessed quality of life (QoL) and appetite. DESIGN: An open, randomized trial. SETTING: Godthaab Health and Rehabilitation Institution in Bærum, Norway. PARTICIPANTS: Patients identified as being undernourished or at risk of disease-related malnutrition using the Nutritional Risk Screening tool NRS-2002. INTERVENTION: Shortly before discharge, patients in the intervention group received an individually-tailored nutrition plan. During the subsequent 3 months these patients were contacted 3 times via telephone calls and they received one visit at their homes, for nutrition counselling. Focus on this counselling was on optimizing meal environment, improving appetite, increasing food intake, advice on food preparation, and motivation and support. MEASUREMENTS: In addition to weight, QoL and appetite were assessed using the EQ-5D questionnaire and a modified version of the Disease-Related Appetite Questionnaire, respectively. RESULTS: Among 115 considered eligible for the study, 100 were enrolled (72 women and 28 men), with a mean age of 75 years and a mean body mass index of 20 kg/m2. Two in the intervention group (n = 52) and 5 in the control group (n = 48) lost > 5% of their body weight, giving an odds ratio of 0.34 (95% CI: 0.064 - 1.86; p = 0.22). We did not detect any significant differences in the QoL- or appetite scores between the two study groups after three months. CONCLUSION: An individually-adapted nutritional counselling did not improve body mass among elderly patients 3 months after discharge from a rehabilitation institution. Neither quality of life nor appetite measures were improved. Possibly, nutritional counselling should be accompanied with nutritional supplementation to be effective in this vulnerable group of elderly. The trial is registered in Clinical Trials (ID: NCT01632072).


Assuntos
Apetite , Peso Corporal , Desnutrição/dietoterapia , Qualidade de Vida , Idoso , Índice de Massa Corporal , Aconselhamento , Determinação de Ponto Final , Feminino , Instituição de Longa Permanência para Idosos , Humanos , Masculino , Desnutrição/reabilitação , Noruega , Casas de Saúde , Alta do Paciente , Inquéritos e Questionários
17.
Clin Nutr ; 36(1): 49-64, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27642056

RESUMO

BACKGROUND: A lack of agreement on definitions and terminology used for nutrition-related concepts and procedures limits the development of clinical nutrition practice and research. OBJECTIVE: This initiative aimed to reach a consensus for terminology for core nutritional concepts and procedures. METHODS: The European Society of Clinical Nutrition and Metabolism (ESPEN) appointed a consensus group of clinical scientists to perform a modified Delphi process that encompassed e-mail communication, face-to-face meetings, in-group ballots and an electronic ESPEN membership Delphi round. RESULTS: Five key areas related to clinical nutrition were identified: concepts; procedures; organisation; delivery; and products. One core concept of clinical nutrition is malnutrition/undernutrition, which includes disease-related malnutrition (DRM) with (eq. cachexia) and without inflammation, and malnutrition/undernutrition without disease, e.g. hunger-related malnutrition. Over-nutrition (overweight and obesity) is another core concept. Sarcopenia and frailty were agreed to be separate conditions often associated with malnutrition. Examples of nutritional procedures identified include screening for subjects at nutritional risk followed by a complete nutritional assessment. Hospital and care facility catering are the basic organizational forms for providing nutrition. Oral nutritional supplementation is the preferred way of nutrition therapy but if inadequate then other forms of medical nutrition therapy, i.e. enteral tube feeding and parenteral (intravenous) nutrition, becomes the major way of nutrient delivery. CONCLUSION: An agreement of basic nutritional terminology to be used in clinical practice, research, and the ESPEN guideline developments has been established. This terminology consensus may help to support future global consensus efforts and updates of classification systems such as the International Classification of Disease (ICD). The continuous growth of knowledge in all areas addressed in this statement will provide the foundation for future revisions.


Assuntos
Desnutrição/diagnóstico , Desnutrição/terapia , Política Nutricional , Terminologia como Assunto , Caquexia/complicações , Consenso , Dieta , Nutrição Enteral , Fragilidade/complicações , Humanos , Avaliação Nutricional , Estado Nutricional , Obesidade/complicações , Sobrepeso/complicações , Nutrição Parenteral , Sarcopenia/complicações , Sociedades Científicas
18.
Adv Immunol ; 51: 85-214, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1386962

RESUMO

The work reviewed in this article separates T cell development into four phases. First is an expansion phase prior to TCR rearrangement, which appears to be correlated with programming of at least some response genes for inducibility. This phase can occur to some extent outside of the thymus. However, the profound T cell deficit of nude mice indicates that the thymus is by far the most potent site for inducing the expansion per se, even if other sites can induce some response acquisition. Second is a controlled phase of TCR gene rearrangement. The details of the regulatory mechanism that selects particular loci for rearrangement are still not known. It seems that the rearrangement of the TCR gamma loci in the gamma delta lineage may not always take place at a developmental stage strictly equivalent to the rearrangement of TCR beta in the alpha beta lineage, and it is not clear just how early the two lineages diverge. In the TCR alpha beta lineage, however, the final gene rearrangement events are accompanied by rapid proliferation and an interruption in cellular response gene inducibility. The loss of conventional responsiveness is probably caused by alterations at the level of signaling, and may be a manifestation of the physiological state that is a precondition for selection. Third is the complex process of selection. Whereas peripheral T cells can undergo forms of positive selection (by antigen-driven clonal expansion) and negative selection (by abortive stimulation leading to anergy or death), neither is exactly the same phenomenon that occurs in the thymic cortex. Negative selection in the cortex appears to be a suicidal inversion of antigen responsiveness: instead of turning on IL-2 expression, the activated cell destroys its own chromatin. The genes that need to be induced for this response are not yet identified, but it is unquestionably a form of activation. It is interesting that in humans and rats, cortical thymocytes undergoing negative selection can still induce IL-2R alpha expression and even be rescued in vitro, if exogenous IL-2 is provided. Perhaps murine thymocytes are denied this form of rescue because they shut off IL-2R beta chain expression at an earlier stage or because they may be uncommonly Bcl-2 deficient (cf. Sentman et al., 1991; Strasser et al., 1991). Even so, medullary thymocytes remain at least partially susceptible to negative selection even as they continue to mature.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Subpopulações de Linfócitos T/imunologia , Animais , Antígenos CD/genética , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/imunologia , Complexo CD3 , Morte Celular , Diferenciação Celular , Divisão Celular , Movimento Celular , Embrião de Galinha , Regulação da Expressão Gênica , Rearranjo Gênico do Linfócito T , Células-Tronco Hematopoéticas/citologia , Humanos , Tolerância Imunológica , Imunidade Celular , Interleucina-2/biossíntese , Interleucina-2/genética , Ativação Linfocitária , Linfocinas/biossíntese , Linfocinas/fisiologia , Camundongos , Camundongos Nus/imunologia , Camundongos SCID/genética , Camundongos SCID/imunologia , Modelos Biológicos , Proteínas Proto-Oncogênicas/fisiologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais , Subpopulações de Linfócitos T/citologia , Timo/citologia , Timo/crescimento & desenvolvimento , Fatores de Transcrição/fisiologia
19.
Cancer Res ; 55(6): 1242-7, 1995 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-7533660

RESUMO

Previous studies have shown that PC12 cells undergo apoptosis (programmed cell death) when deprived of serum. In the present study, we examined the relationship of this death process to the cell cycle. PC12 cell populations synchronized at different, specific phases of the cell cycle exhibit similar kinetics of cell death following deprivation of serum. Flow cytometry analysis was used to examine the levels of apoptotic death in these cell populations in relationship to their progression in the cell cycle during the course of serum deprivation. Such analysis revealed that the cells die during the G0-G1, S, and perhaps G2-M phases and at the G2 to G1 transition. These results, therefore, suggest that the death of synchronized, serum-deprived PC12 cells occurs throughout the cell cycle and is not dependent on growth arrest. Flow cytometry methodology (acridine orange staining), which determines the RNA content of cells in relationship to their position in the cell cycle, was used to address these questions in nonsynchronized cells. These experiments revealed that, upon serum deprivation, an immediate loss of RNA occurred from cells in G1, S, and G2-M phases. This loss is accompanied by a slower appearance of cells with degraded DNA content. These results show that cells from all phases of the cell cycle are damaged upon serum deprivation and thus suggest that the apoptotic cell death of nonsynchronized PC12 cells may occur from each phase of the cell cycle.


Assuntos
Apoptose , Fenômenos Fisiológicos Sanguíneos , Substâncias de Crescimento/fisiologia , Animais , Ciclo Celular , DNA/análise , Células PC12 , RNA/análise , Ratos
20.
Eur J Clin Nutr ; 69(2): 256-61, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24801370

RESUMO

BACKGROUND/OBJECTIVES: Anorexia or lack of appetite is common in chronic obstructive pulmonary disease (COPD) and may be caused or augmented by several symptoms affecting appetite and eating. We aimed to investigate and quantify the extent of nutrition impact symptoms (NIS) in patients with COPD and to explore relationships between NIS and fat-free mass depletion. SUBJECTS/METHODS: The results in this cross-sectional study are based on 169 COPD patients (62% female subjects). Body composition was assessed using bioelectrical impedance spectroscopy and the patients reported NIS by two newly developed questionnaires: the Eating Symptoms Questionnaire (ESQ) and the Disease-Related Appetite Questionnaire (DRAQ). RESULTS: Symptoms with the highest prevalence were dry mouth (71%), stomach ache (39%), pain or aches affecting appetite (36%) and constipation (35%). Problems with diarrhoea and feeling affected by smells were more severe among women compared with men (P<0.05). Thirty-six percent of the patients were depleted (fat-free mass index (FFMI) <15 kg/m2 for women and FFMI<16 kg/m2 for men). Depleted patients had more NIS (P<0.05) and also rated appetite and taste of food as worse compared with non-depleted patients (P<0.05). CONCLUSIONS: NIS are common in patients with COPD, and depleted patients have more severe symptoms. To investigate how these symptoms are best prevented and/or managed and whether NIS prevention/treatment can affect development of malnutrition in patients with COPD is a challenge for the future.


Assuntos
Apetite , Composição Corporal , Compartimentos de Líquidos Corporais/metabolismo , Ingestão de Alimentos , Transtornos da Alimentação e da Ingestão de Alimentos/etiologia , Estado Nutricional , Doença Pulmonar Obstrutiva Crônica/complicações , Idoso , Índice de Massa Corporal , Peso Corporal , Estudos Transversais , Impedância Elétrica , Feminino , Gastroenteropatias/etiologia , Humanos , Masculino , Desnutrição/etiologia , Pessoa de Meia-Idade , Dor/etiologia , Doença Pulmonar Obstrutiva Crônica/metabolismo , Fatores Sexuais , Olfato , Inquéritos e Questionários , Paladar
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