RESUMO
The paper deals with the actual feeding status of infants in intensive care units (ICU). A total of 275 children aged 1 month to 15 years, treated in the ICU of a Tushino children's city hospital, Moscow, for brain injury, pyoinflammatory abdominal diseases, and severe pneumonia in 2000-2006, were examined to study the dietary provision of children in the ICU with essential nutrients and calories depending on age and feeding mode over time in the early post-aggression period. Mixed (parenteral and enteral) feeding was found to provide dietary intake with significantly large quantities of essential nutrients and calories than enteral feeding alone. At the same time, the changes between the enteral feeding and mixed feeding groups in such indices as the quantity of ingested protein, fat, and calories were significant (p < 0.05).
Assuntos
Ingestão de Energia , Nutrição Enteral , Unidades de Terapia Intensiva Pediátrica/normas , Nutrição Parenteral , Adolescente , Criança , Pré-Escolar , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Ingestão de Energia/fisiologia , Nutrição Enteral/métodos , Nutrição Enteral/normas , Humanos , Lactente , Minerais/administração & dosagem , Nutrição Parenteral/métodos , Nutrição Parenteral/normas , Vitaminas/administração & dosagemRESUMO
Thrombin stimulates the expression of multiple genes in endothelial cells (ECs), but the trans-acting factors responsible for this induction remain undefined. We have previously described a thrombin-inducible nuclear factor (TINF), which binds to an element in the PDGF B promoter and is responsible for the thrombin inducibility of this gene. Inactive cytoplasmic TINF is rapidly activated and translocated to nuclei of ECs upon stimulation with thrombin. We have now purified TINF from thrombin-treated ECs. Amino acid sequencing revealed it to be a member of the Y-box protein family, and the sole Y-box protein-encoding cDNA we detected in human or bovine ECs corresponded to DNA-binding protein B (dbpB). DbpB translocated to the nucleus after thrombin stimulation of ECs as shown by FACS analysis of nuclei from ECs expressing GFP-dbpB fusion proteins. During thrombin activation, dbpB was found to be cleaved, yielding a 30-kDa NH(2)-terminal fragment that recognized the thrombin-response element sequence, but not the Y-box consensus sequence. Preincubation of ECs with protein tyrosine phosphatase inhibitors completely blocked dbpB activation by thrombin and blocked induction of endogenous PDGF B-chain mRNA and promoter activation by thrombin. Y-box proteins are known to act constitutively to regulate the expression of several genes. Activation of this class of transcription factors in response to thrombin or any other agonist represents a novel signaling pathway.
Assuntos
Proteínas Estimuladoras de Ligação a CCAAT , Proteínas de Ligação a DNA/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Trombina/farmacologia , Fatores de Transcrição , Sequência de Aminoácidos , Animais , Sequência de Bases , Bovinos , Células Cultivadas , Sondas de DNA/genética , Proteínas de Ligação a DNA/genética , Expressão Gênica/efeitos dos fármacos , Humanos , Fatores de Transcrição NFI , Proteínas Nucleares , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína 1 de Ligação a Y-BoxRESUMO
BACKGROUND: Recent advances in high-throughput genomics technology have expanded our ability to catalogue allelic variants in large sets of candidate genes related to premature coronary artery disease. METHODS AND RESULTS: A total of 398 families were identified in 15 participating medical centers; they fulfilled the criteria of myocardial infarction, revascularization, or a significant coronary artery lesion diagnosed before 45 years in men or 50 years in women. A total of 62 vascular biology genes and 72 single-nucleotide polymorphisms were assessed. Previously undescribed variants in 3 related members of the thrombospondin protein family were prominent among a small set of single-nucleotide polymorphisms that showed a statistical association with premature coronary artery disease. A missense variant of thrombospondin 4 (A387P) showed the strongest association, with an adjusted odds ratio for myocardial infarction of 1.89 (P=0.002 adjusted for covariates) for individuals carrying the P allele. A variant in the 3' untranslated region of thrombospondin-2 (change of thymidine to guanine) seemed to have a protective effect against myocardial in individuals homozygous for the variant (adjusted odds ratio of 0.31; P=0.0018). A missense variant in thrombospondin-1 (N700S) was associated with an adjusted odds ratio for coronary artery disease of 11.90 (P=0.041) in homozygous individuals, who also had the lowest level of thrombospondin-1 by plasma assay (P=0.0019). CONCLUSIONS: This large-scale genetic study has identified the potential of multiple novel variants in the thrombospondin gene family to be associated with familial premature myocardial infarction. Notwithstanding multiple caveats, thrombospondins specifically and high-throughput genomic technology in general deserve further study in familial ischemic heart disease.
Assuntos
Doença da Artéria Coronariana/genética , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/genética , Polimorfismo de Nucleotídeo Único/genética , Trombospondinas/genética , Adulto , Idade de Início , Alelos , Estudos de Casos e Controles , Angiografia Coronária , Doença da Artéria Coronariana/epidemiologia , Estenose Coronária/diagnóstico , Estenose Coronária/genética , Demografia , Feminino , Predisposição Genética para Doença , Testes Genéticos , Genótipo , Homozigoto , Humanos , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2) , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Razão de Chances , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Valor Preditivo dos Testes , Trombospondina 1/genética , Estados UnidosRESUMO
Endothelial dysfunction is an early sign of diabetic vascular disease. Due to their unique position at the border between blood and vascular tissue, endothelial cells (EC) are the first vascular cells to sensor humoral changes, and they are able to transmit the information about these changes to other vascular cell types by changing their gene expression profile and producing growth factors, cytokines, adhesion molecules, and other bioactive molecules. These signals alter vascular cell dynamics and interactions, vascular tone and result in inability of the vessel to maintain athrombogenic luminal surface and in alteration of vascular permeability. Although researchers have yet to uncover the precise mechanism(s) that leads to diabetic vascular disease, hyperglycemia has been identified as an independent risk factor for micro- and macrovascular complications. Elevated levels of glucose induce the expression of a variety of genes related to atherogenesis and angiogenesis regulation. However, most of our current knowledge about the molecular mechanisms used by glucose to regulate gene expression is based on studies that used cells with insulin-dependent glucose transport (hepatocytes, adipocytes). Such cells are significantly different than vascular cells, in which glucose uptake is mostly imparted by insulin-independent mechanisms. This review summarizes current information about the effects of hyperglycemia and elevated glucose in in vitro systems on vascular gene expression and molecular transcriptional and post-transcriptional mechanisms that may regulate the changes related to diabetic vascular complications.
Assuntos
Vasos Sanguíneos/fisiologia , Angiopatias Diabéticas/genética , Glucose/fisiologia , Animais , Angiopatias Diabéticas/metabolismo , Angiopatias Diabéticas/fisiopatologia , Endotélio Vascular/fisiologia , Regulação da Expressão Gênica/fisiologia , Glucose/metabolismo , Humanos , Transdução de Sinais/fisiologiaRESUMO
The authors investigated the expression of cytoskeletal proteins and the ultrastructure of cells in normal intima and atheromatous plaque of human aorta. It has been established, using double immunofluorescent method and a set of antibodies that intimal smooth muscle cells /SMC/ of normal aorta express myosin, vimentin, alpha-actin and actin but not desmin. In seven out of 28 atherosclerotic plaques the cells contained desmin and all other SMC cytoskeletal proteins were found. These cells had the ultrastructural features of SMC, i.e. well-developed endoplasmic reticulum and Golgi apparatus. Besides, some cells in 13 atherosclerotic plaques proved to be myosin-, alpha-actin- and desmin-negative. The cells were stained with monoclonal antibodies specific to SMC but not with macrophage-specific antibody. Ultrastructurally, the cytoplasm of the cells was filled with rough endoplasmic reticulum and a developed Golgi complex, but a certain portion of the cells retained basal lamina and myofilament bundles. The peculiarities of cytoskeletal protein in expression and ultrastructure of cells in human aortic atherosclerotic plaques may be explained by a phenotypic modulation of vascular SMC.
Assuntos
Arteriosclerose/patologia , Variação Genética , Músculo Liso Vascular/ultraestrutura , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aorta/metabolismo , Aorta/ultraestrutura , Arteriosclerose/metabolismo , Proteínas do Citoesqueleto/metabolismo , Imunofluorescência , Histocitoquímica , Humanos , Microscopia Eletrônica , Pessoa de Meia-Idade , Proteínas Musculares/metabolismo , Músculo Liso Vascular/metabolismo , FenótipoRESUMO
The serotyping of pneumococci isolated from different material obtained from children aged 0 to 11 years was carried out. Out of 156 patients with different diseases, hospitalized in two clinics in Moscow during February-May 1983, pneumococci were isolated from 67 patients (43%). The isolated pneumococcal strains belonged to 11 serotypes. Pneumococci of serotypes 3, 6, 9 and 19 were shown to occur most frequently in different diseases and constituted 50% of the isolated strains. The inoculation of the material by the quantitative method permitted the authors to find out the role of pneumococci as the etiological factor in the pathogenesis of some diseases. A certain dependence of diversity in the types of isolated pneumococci on the age of sick children was noted. Almost all isolated strains were found to be sensitive to penicillin, ampicillin and benzylpenicillin. But a few individual strains were sensitive only to one of these antibiotics. The data on some biological properties of pneumococci cultivated on solid culture media are presented.
Assuntos
Infecções Respiratórias/microbiologia , Streptococcus pneumoniae/classificação , Fatores Etários , Testes de Aglutinação , Animais , Antibacterianos/farmacologia , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Camundongos , Testes de Sensibilidade Microbiana , Infecções Respiratórias/etiologia , Sorotipagem , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/isolamento & purificação , VirulênciaRESUMO
We have recently demonstrated that thrombin induces expression of the platelet-derived growth factor B-chain gene in endothelial cells (EC) through activation of the Y-box binding protein DNA-binding protein B (dbpB). We now present evidence that dbpB is activated by a novel mechanism: proteolytic cleavage leading to release from mRNA, nuclear translocation, and induction of thrombin-responsive genes. Cytosolic, full-length dbpB (50 kDa) was rapidly cleaved to a 30-kDa species upon thrombin stimulation of EC. This truncated, "active" dbpB exhibited nuclear localization and binding affinity for the thrombin response element sequence, which is distinct from the Y-box sequence. Oligo(dT) affinity chromatography revealed that cytosolic dbpB from control EC, but not active dbpB from thrombin-treated EC, was bound to mRNA. Latent dbpB immunoprecipitated from cytosolic extracts of control EC was activated by ribonuclease treatment. Furthermore, when EC cytosolic extracts were subjected to Nycodenz gradient centrifugation, latent dbpB fractionated with mRNA, whereas active dbpB fractionated with free proteins. The cytosolic retention domain of dbpB, which we localized to the region 247-267, was proteolytically cleaved during its activation. In contrast to full-length dbpB, truncated dbpB stimulated platelet-derived growth factor B-chain and tissue factor promoter activity by over 5-fold when transiently cotransfected with reporter constructs. These results suggest a novel mode of transcription factor activation in which an agonist causes release from mRNA of a latent transcription factor leading to its transport to the nucleus and its regulation of target gene expression.
Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Proteínas de Ligação a DNA/metabolismo , Endotélio Vascular/metabolismo , Fator de Crescimento Derivado de Plaquetas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Trombina/farmacologia , Fatores de Transcrição , Ativação Transcricional , Células 3T3 , Sequência de Aminoácidos , Animais , Aorta , Sítios de Ligação , Bovinos , Núcleo Celular/metabolismo , Citosol/metabolismo , Endotélio Vascular/citologia , Camundongos , Dados de Sequência Molecular , Fatores de Transcrição NFI , Proteínas Nucleares , Polirribossomos/metabolismo , Regiões Promotoras Genéticas , Transporte Proteico , RNA Mensageiro/efeitos dos fármacos , RNA Ribossômico 5S/metabolismo , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Proteína 1 de Ligação a Y-BoxRESUMO
This study was undertaken to investigate the expression of cytoskeletal proteins and the ultrastructure of cells in normal intima and atheromatous plaque of human aorta. It has been established, using double-labeling immunofluorescence, that smooth muscle cells (SMC) in normal aortic intima contain myosin, vimentin, and alpha-actin but do not react with antibodies against desmin. In contrast, 7 of 28 atherosclerotic plaques contained many cells expressing desmin in addition to the other cytoskeletal proteins characteristic of normal intima SMC. These cells were localized predominantly in the plaque cap and had the ultrastructural features of modulated SMC, ie, well-developed endoplasmic reticulum and Golgi apparatus. Besides, some cells in the 13 atherosclerotic plaques proved to be myosin, alpha actin, and desmin negative but contained vimentin and actin as revealed by fluorescent phalloidin. These cells were found in the immediate proximity of atheromatous material and reacted with a monoclonal antibody specific to SMC surface protein (11G10) but not with monoclonal anti-muscle actin (HHF35) and anti-macrophage (HAM56) antibodies. Electron microscopy of this plaque zone revealed that the cytoplasm of these cells was filled with rough endoplasmic reticulum and a developed Golgi complex. At the same time, a certain proportion of cells in this region retained morphologic features of differentiated SMC such as the presence of a basal lamina and myofilament bundles. The revealed peculiarities of cytoskeletal protein expression and the ultrastructure of cells in human aortic atherosclerotic plaques may be explained by a phenotypic modulation of vascular SMC.
Assuntos
Aorta/patologia , Arteriosclerose/patologia , Músculo Liso Vascular/patologia , Adolescente , Adulto , Idoso , Aorta/metabolismo , Arteriosclerose/metabolismo , Proteínas do Citoesqueleto/metabolismo , Imunofluorescência , Humanos , Microscopia Eletrônica , Pessoa de Meia-Idade , Músculo Liso Vascular/metabolismoRESUMO
Beta-adrenoceptor agonist isoproterenol potentiates the damaging effect of angiotensin II on rabbit aorta endothelium. Compared to the action of angiotensin II alone the amounts of injured cells, damaged intercellular contacts, cell form change, silver uptake and 125I--LDL uptake are increased under simultaneous action of angiotensin II and isoproterenol. Disturbance in barrier function is associated with the damaged cell contracts and cell death. 125I--LDL uptake increase is due to their accumulation in the adventitia. The simultaneous increase in angiotensin II and beta-adrenoceptor activating agents concentrations can damage endothelium and disturb its barrier function.
Assuntos
Angiotensina II/efeitos adversos , Endotélio Vascular/efeitos dos fármacos , Isoproterenol/efeitos adversos , Animais , Aorta , Sinergismo Farmacológico , Endotélio Vascular/citologia , Endotélio Vascular/fisiologia , CoelhosRESUMO
The vitamin K-dependent (VKD) carboxylase binds VKD proteins via their propeptide and converts Glu's to gamma-carboxylated Glu's, or Gla's, in the Gla domain. Multiple carboxylation is required for activity, which could be achieved if the carboxylase is processive. In the only previous study to test for this capability, an indirect assay was used which suggested processivity; however, the efficiency was poor and raised questions regarding how full carboxylation is accomplished. To unequivocally determine if the carboxylase is processive and if it can account for comprehensive carboxylation in vivo, as well as to elucidate the enzyme mechanism, we developed a direct test for processivity. The in vitro carboxylation of a complex containing carboxylase and full-length factor IX (fIX) was challenged with an excess amount of a distinguishable fIX variant. Remarkably, carboxylation of fIX in the complex was completely unaffected by the challenge protein, and comprehensive carboxylation was achieved, showing conclusively that the carboxylase is processive and highly efficient. These studies also showed that carboxylation of individual fIX/carboxylase complexes was nonsynchronous and implicated a driving force for the reaction which requires the carboxylase to distinguish Glu's from Gla's. We found that the Gla domain is tightly associated with the carboxylase during carboxylation, blocking the access of a small peptide substrate (EEL). The studies describe the first analysis of preformed complexes, and the rate for full-length, native fIX in the complex was equivalent to that of the substrate EEL. Thus, intramolecular movement within the Gla domain to reposition new Glu's for catalysis is as rapid as diffusion-limited positioning of a small substrate, and the Gla domain is not sterically constrained by the rest of the fIX molecule during carboxylation. The rate of carboxylation of fIX in the preformed complex was 24-fold higher than for fIX modified by free carboxylase, which supports carboxylase processivity and which indicates that binding and/or release is the rate-limiting step in protein carboxylation. These data indicate a model of tethered processivity, in which the VKD proteins remain bound to the carboxylase throughout the reaction via their propeptide, while the Gla domain undergoes intramolecular movement to reposition new Glu's for catalysis to ultimately achieve comprehensive carboxylation.
Assuntos
Carbono-Carbono Ligases/química , Carbono-Carbono Ligases/metabolismo , Fator IX/química , Fator IX/metabolismo , Ácido Glutâmico , Animais , Linhagem Celular , Clonagem Molecular , Cricetinae , Humanos , Cinética , Modelos Moleculares , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Especificidade por Substrato , TransfecçãoRESUMO
A method for quantitative analysis of interaction between 125I-LDL with perfused rabbit vessels in situ was developed. The method suggested enables the preservation of the integrity of the endothelium in the perfused vascular segment and the study of 125I-LDL incorporation into the affected vessels within the concentration ranges that make possible specific incorporation of LDL into cells. The method can be applied to studying the mechanisms and modulations of LDL uptake by the vascular wall in situ.