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BACKGROUND: Contemporary data regarding the characteristics, treatment and outcomes of patients with atrial fibrillation (AF) are needed. We aimed to assess these data and guideline adherence in the EURObservational Research Programme on Atrial Fibrillation (EORP-AF) long-term general registry. METHODS: We analysed 967 patients from the EORP-AF long-term general registry included in the Netherlands and Belgium from 2013 to 2016. Baseline and 1year follow-up data were gathered. RESULTS: At baseline, 887 patients (92%) received anticoagulant treatment. In 88 (10%) of these patients, no indication for chronic anticoagulant treatment was present. A rhythm intervention was performed or planned in 52 of these patients, meaning that the remaining 36 (41%) were anticoagulated without indication. Forty patients were not anticoagulated, even though they had an indication for chronic anticoagulation. Additionally, 63 of the 371 patients (17%) treated with a non-vitamin K antagonist oral anticoagulant (NOAC) were incorrectly dosed. In total, 50 patients (5%) were overtreated and 89 patients (9%) were undertreated. However, the occurrence of major adverse cardiac and cerebrovascular events (MACCE) was still low with 4.2% (37 patients). CONCLUSIONS: Overtreatment and undertreatment with anticoagulants are still observable in 14% of this contemporary, West-European AF population. Still, MACCE occurred in only 4% of the patients after 1 year of follow-up.
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BACKGROUND: Fractures of the hand and wrist are one of the most common injuries seen in adults. The Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire has been developed as a patient-reported assessment of pain and disability to evaluate the outcome after hand and wrist injuries. Patient reported outcomes (PROs) can be interpreted as pain, function or patient satisfaction. To be able to interpret clinical relevance of a PRO, the structural validity and internal consistency is tested. The Dutch version of the DASH has not yet been validated. The aim of this study was to evaluate the structural validity and the internal consistency of the existing Dutch version of the DASH. The relevance of reporting subscale scores was investigated. METHODS: This study was a retrospective analysis of cross-sectional data of 370 patients with an isolated hand or wrist injury. Adult patients aged 18 to 65 years treated conservatively or surgically were included. Patients unable to understand or read the Dutch language were excluded. Confirmatory factor analysis was used to investigate the structural validity, while Cronbach's alpha and coefficient omega were used to assess internal consistency. RESULTS: All investigated models (a single factor model, a 3-correlated factor, and a bifactor model) were associated with a good model fit. Both the single factor and the 3-correlated factor model were associated with factor loadings of at least 0.70. In addition, the covariance between the factors in the 3-correlated factor model was positive (at least 0.89) and statistically significant (p < 0.001). In the bifactor model, the additional value of subscales was limited as the items loaded high on the general factor but low on the subscale factors. CONCLUSION: This study indicates that the Dutch version of the DASH should be considered as an unidimensional trait. A single score should be reported.
Assuntos
Braço , Avaliação da Deficiência , Traumatismos da Mão/diagnóstico , Ombro , Inquéritos e Questionários/normas , Traumatismos do Punho/diagnóstico , Adolescente , Adulto , Idoso , Braço/patologia , Estudos Transversais , Pessoas com Deficiência , Feminino , Traumatismos da Mão/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Medição da Dor/métodos , Medição da Dor/normas , Reprodutibilidade dos Testes , Estudos Retrospectivos , Ombro/patologia , Traumatismos do Punho/epidemiologia , Adulto JovemRESUMO
Antibodies recognizing denatured human leucocyte antigen (HLA) can co-react with epitopes on intact HLA or recognize cryptic epitopes which are normally unaccessible to HLA antibodies. Their specificity cannot be distinguished by single antigen beads (SAB) alone, as they carry a mixture of intact and denatured HLA. In this study, we selected pretransplant sera containing donor-specific HLA class I antibodies (DSA) according to regular SAB analysis from 156 kidney transplant recipients. These sera were analysed using a SAB preparation (iBeads) which is largely devoid of denatured HLA class I, and SAB coated with denatured HLA class I antigens. A total of 241 class I DSA were found by regular SAB analysis, of which 152 (63%) were also found by iBeads, whereas 28 (11%) were caused by reactivity with denatured DNA. Patients with DSA defined either by regular SAB or iBeads showed a significantly lower graft survival rate (P = 0·007) compared to those without HLA class I DSA, whereas reactivity to exclusively denatured HLA was not associated with decreased graft survival. In addition, DSA defined by reactivity to class I SAB or class I iBeads occurred more frequently in female patients and in patients with historic HLA sensitization, whereas reactivity to denatured HLA class I was not associated with any of these parameters. Our data suggest that pretransplant donor-specific antibodies against denatured HLA are clinically irrelevant in patients already sensitized against intact HLA.
Assuntos
Antígenos HLA/imunologia , Isoanticorpos/imunologia , Transplante de Rim/imunologia , Doadores de Tecidos , Adulto , Especificidade de Anticorpos/imunologia , Feminino , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Antígenos HLA/química , Humanos , Isoanticorpos/sangue , Masculino , Pessoa de Meia-Idade , Ligação Proteica/imunologia , Desnaturação ProteicaRESUMO
BACKGROUND: Cerebral palsy (CP) is a well-recognized neurodevelopmental condition persisting through the lifespan. In many individuals with CP, motor disorders are accompanied by other disturbances, including emotional and behavioural problems. Little is known on the course of such problems, also in relation to possible exacerbating or mitigating factors. Aims of this study were to test whether parental stress and support, apart from the severity of CP of the child, played a significant role in the course of behaviour problems. METHOD: The participants aged 9, 11 and 13 were assessed (baseline) and followed up after 1, 2 and 3 years. Situational and relational sources of support and stress for the primary caregiver were rated with a questionnaire: (CBCL), behaviour problems with the Child Behaviour Checklist. Physicians rated motor ability using the Gross Motor Function Classification System. RESULTS: Behaviour problems of children with CP started significantly higher than in the general population, but diminished over the 3-year period. Older children showed less problems overall, and girls showed less externalizing problems than boys. Children with the most severe CP had more externalizing problems; effects on internalizing problems were not significant. Across time, an excess of stress vs. support related to parents' socio-economic and living situation and to parents' social relationships was positively related to total behaviour problems, internalizing and externalizing behaviours of children. CONCLUSIONS: Levels of behaviour problems are elevated but diminish during adolescence for children with CP. Severity of CP plays a role as well as the family context in terms of the stress and support that caregivers experience.
Assuntos
Cuidadores/psicologia , Paralisia Cerebral/psicologia , Transtornos do Comportamento Infantil/psicologia , Pais/psicologia , Estresse Psicológico , Adolescente , Adulto , Criança , Transtornos do Comportamento Infantil/etiologia , Feminino , Humanos , Controle Interno-Externo , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Destreza Motora/classificação , Relações Pais-FilhoRESUMO
A metabolomic approach was applied to a mouse model of starvation-induced hepatic steatosis. After 24 h of fasting it appears that starvation reduced the phospholipids (PL), free cholesterol (FC), and cholesterol esters (CE) content of low-density lipoproteins (LDL). In liver lipid profiles major changes were observed using different techniques. High performance thin layer chromatography (HPTLC)-measurements of liver-homogenates indicated a significant rise of FC with 192%, triacylglycerols (TG) with 456% and cholesterol esters (CE) with 268% after 24 h of starvation in comparison with the control group. Reversed phase liquid chromatography coupled to mass spectrometry measurements (LC-MS) of liver homogenate indicated that the intensity of Phosphatidylcholine (PC) in the 24-h starvation group dropped to 90% of the value in the control group while the intensity of CE and TG increased to 157% and 331%, respectively, of the control group. Interestingly, a 49:4-TG with an odd number of C atoms appeared during starvation. This unique triacylglycerol has all characteristics of a biomarker for detection of hepatic steatosis. These observations indicate that in mammals liver lipid profiles are a dynamic system which are readily modulated by environmental factors like starvation.
Assuntos
Sangue/metabolismo , Fígado Gorduroso/metabolismo , Fígado/metabolismo , Animais , Ésteres do Colesterol/metabolismo , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Privação de Alimentos , Lipoproteínas LDL/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosfatidilcolinas/metabolismo , Fosfolipídeos/metabolismo , Triglicerídeos/metabolismoRESUMO
OBJECTIVE: Cholesterol ester transfer protein (CETP) plays an important role in HDL cholesterol metabolism. Leucocytes, including monocyte-derived macrophages in the arterial wall synthesize and secrete CETP, but its role in atherosclerosis is unclear. The aim of the current study was to investigate the effect of acute coronary syndromes (ACS) on leucocyte CETP expression. RESEARCH DESIGN: Peripheral blood mononuclear cells (PBMCs) were freshly isolated from hospitalized ACS patients displaying Braunwald class IIIB unstable angina pectoris (UAP) on admission (t = 0) and at 180 days post inclusion (t = 180) for analysis of CETP expression. In addition, to prove the potential correlation between leucocyte CETP and ACS the effect of acute myocardial infarction on leucocyte CETP expression was studied in CETP transgenic mice. RESULTS: Upon admission, UAP patients displayed approximately 3-6 fold (P < 0.01) lower CETP mRNA and nearly absent CETP protein expression in PBMCs, as compared to healthy age-/sex-matched controls. Interestingly, CETP mRNA and protein levels were significantly elevated in PBMCs isolated from UAP patients (both stabilized and refractory) at t = 180 as compared to t = 0 (P < 0.01), which was correlated with a reduced inflammatory status after medical treatment. In agreement with the data obtained in UAP patients, markedly down-regulated leucocyte CETP mRNA expression was observed after coronary artery ligation in CETP transgenic mice, which also correlated with increased serum amyloid A levels. CONCLUSIONS: We are the first to report that episodes of UAP in humans and myocardial infarction in CETP transgenic mice are associated with reduced leucocyte CETP expression. We propose that the impairment in leucocyte CETP production is associated with an enhanced inflammatory status, which could be clinically relevant for the pathogenesis of ACS.
Assuntos
Síndrome Coronariana Aguda/metabolismo , Proteínas de Transferência de Ésteres de Colesterol/análise , Leucócitos Mononucleares/metabolismo , Síndrome Coronariana Aguda/imunologia , Doença Aguda , Idoso , Animais , Colesterol/sangue , Proteínas de Transferência de Ésteres de Colesterol/genética , HDL-Colesterol/sangue , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Modelos AnimaisRESUMO
Cell proliferation and cell death (either necrosis or apoptosis) are key processes in the progression of atherosclerosis. The tumor suppressor gene p53 is an essential gene in cell proliferation and cell death and is upregulated in human atherosclerotic plaques, both in smooth muscle cells and in macrophages. In the present study, we investigated the importance of macrophage p53 in the progression of atherosclerosis using bone marrow transplantation in APOE*3-Leiden transgenic mice, an animal model for human-like atherosclerosis. APOE*3-Leiden mice were lethally irradiated and reconstituted with bone marrow derived from either p53-deficient (p53(-/-)) or control (p53(+/+)) donor mice. Reconstitution of mice with p53(-/-) bone marrow did not result in any hemopoietic abnormalities as compared with p53(+/+) transplanted mice. After 12 weeks on an atherogenic diet, APOE*3-Leiden mice reconstituted with p53(-/-) bone marrow showed a significant (P=0.006) 2.3-fold increase in total atherosclerotic lesion area as compared with mice reconstituted with p53(+/+) bone marrow. Although likely a secondary effect of the increased lesion area, p53(-/-) transplanted mice also showed significantly more lesion necrosis (necrotic index, 1.1+/-1.3 versus 0.2+/-0.7; P=0.04) and lesion macrophages (macrophage area, 79.9+/-40.0 versus 39.7+/-27.3x10(3) micrometer(2) per section; P=0.02). These observations coincided with a tendency toward decreased apoptosis (terminal deoxynucleotidyl transferase end-labeling [TUNEL]-positive nuclei going from 0.42+/-0.39 to 0.14+/-0.15%, P=0.071), whereas the number of proliferating cells (5'-bromo-2'-deoxyuridine-positive nuclei) was not affected (3.75+/-0.98 versus 4.77+/-2.30%; P=0.59). These studies indicate that macrophage p53 is important in suppressing the progression of atherosclerosis and identify a novel therapeutic target for regulating plaque stability.
Assuntos
Apolipoproteínas E/genética , Arteriosclerose/genética , Macrófagos/metabolismo , Proteína Supressora de Tumor p53/deficiência , Animais , Valva Aórtica/patologia , Apolipoproteína E3 , Apoptose , Arteriosclerose/metabolismo , Arteriosclerose/patologia , Transplante de Medula Óssea , Contagem de Células , Dieta Aterogênica , Modelos Animais de Doenças , Progressão da Doença , Marcação In Situ das Extremidades Cortadas , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Necrose , Índice de Gravidade de Doença , Baço/patologia , Linfócitos T/metabolismo , Linfócitos T/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
Lipoprotein lipase (LPL) synthesis by macrophages is upregulated in early atherogenesis, implicating the possible involvement of LPL in plaque formation. However, it is still unclear whether macrophage-derived LPL displays a proatherosclerotic or an antiatherosclerotic role in atherosclerotic lesion development. In this study, the role of macrophage-derived LPL on lipid metabolism and atherosclerosis was assessed in vivo by transplantation of LPL-deficient (LPL-/-) and wild-type (LPL+/+) bone marrow into C57BL/6 mice. Eight weeks after bone marrow transplantation (BMT), serum cholesterol levels in LPL-/--->C57BL/6 mice were reduced by 8% compared with those in LPL+/+-->C57BL/6 mice (P:<0.05, n=16), whereas triglycerides were increased by 33% (P:<0.05, n=16). Feeding the mice a high-cholesterol diet increased serum cholesterol levels in LPL-/--->C57BL/6 and LPL+/+-->C57BL/6 mice 5-fold and 9-fold, respectively, resulting in a difference of approximately 50% (P:<0. 01) after 3 months on the diet. No effects on triglyceride levels were observed under these conditions. Furthermore, serum apolipoprotein E levels were reduced by 50% in the LPL-/--->C57BL/6 mice compared with controls under both dietary conditions. After 3 months on a high-cholesterol diet, the atherosclerotic lesion area in LPL-/--->C57BL/6 mice was reduced by 52% compared with controls. It can be concluded that macrophage-derived LPL plays a significant role in the regulation of serum cholesterol, apolipoprotein E, and atherogenesis, suggesting that specific blockade of macrophage LPL production may be beneficial for decreasing atherosclerotic lesion development.
Assuntos
Arteriosclerose/metabolismo , Lipase Lipoproteica/metabolismo , Lipoproteínas/metabolismo , Macrófagos/enzimologia , Animais , Apolipoproteínas E/sangue , Arteriosclerose/sangue , Arteriosclerose/enzimologia , Transplante de Medula Óssea , Colesterol/sangue , Colesterol na Dieta , Feminino , Humanos , Iodo/metabolismo , Lipoproteínas VLDL/metabolismo , Testes de Função Hepática , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Triglicerídeos/sangueRESUMO
In the arterial wall, scavenger receptor class A (SRA) is implicated in pathological lipid deposition. In contrast, in the liver, SRA is suggested to remove modified lipoproteins from the circulation, thereby protecting the body from their pathological action. The role of SRA on bone marrow-derived cells in lipid metabolism and atherogenesis was assessed in vivo by transplantation of bone marrow cells overexpressing human SRA (MSR1) to apoE-deficient mice. In vitro studies with peritoneal macrophages from the transplanted mice showed that macrophage scavenger receptor function, as measured by cell association and degradation studies with acetylated LDL, was approximately 3-fold increased on overexpression of MSR1 in bone marrow-derived cells as compared with control mice. Despite the increased macrophage scavenger receptor function in vitro, no significant effect of MSR1 overexpression in bone marrow-derived cells on the in vivo atherosclerotic lesion development was found. In addition to arterial wall macrophages, liver sinusoidal Kupffer cells also overexpress MSR1 after bone marrow transplantation, which may scavenge atherogenic particles more efficiently from the blood compartment. Introduction of bone marrow cells overexpressing human MSR1 in apoE-deficient mice induced a significant reduction in serum cholesterol levels of approximately 20% (P:<0.001, 2-way ANOVA) as the result of a decrease in VLDL cholesterol. It is suggested that the reduction in VLDL cholesterol levels is due to increased clearance of modified lipoproteins by the overexpressed MSR1 in Kupffer cells of the liver, thereby protecting the arterial wall against the proatherogenic action of modified lipoproteins.
Assuntos
Arteriosclerose/etiologia , Células da Medula Óssea/metabolismo , Macrófagos Peritoneais/metabolismo , Proteínas de Membrana , Receptores Imunológicos/biossíntese , Receptores de Lipoproteínas , Animais , Aorta/patologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Arteriosclerose/sangue , Arteriosclerose/genética , Transplante de Medula Óssea , Células Cultivadas , VLDL-Colesterol/sangue , Feminino , Humanos , Células de Kupffer/metabolismo , Metabolismo dos Lipídeos , Lipoproteínas LDL/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Miocárdio/patologia , Receptores Imunológicos/genética , Receptores Depuradores , Receptores Depuradores Classe A , Receptores Depuradores Classe B , Triglicerídeos/sangue , Irradiação Corporal TotalAssuntos
Apolipoproteína A-II , Aterosclerose , Animais , Colesterol , Dieta , Ezetimiba , Células Espumosas , Peixe-ZebraRESUMO
BACKGROUND: The autonomic nervous system attenuates inflammation through activation of the α7 nicotinic acetylcholine receptor (α7nAChR), a pathway termed the cholinergic anti-inflammatory reflex. Interestingly, α7nAChR is expressed on immune cells and platelets, both of which play a crucial role in the development of atherosclerosis. OBJECTIVE: To investigate the role of hematopoietic α7nAChR in inflammation and platelet function in atherosclerotic ldlr(-/-) mice and to identify its consequences for atherosclerotic lesion development. METHODS: Bone marrow from α7nAChR(-/-) mice or wild-type littermates was transplanted into irradiated ldlr(-/-) mice. After a recovery period of 8 weeks, the mice were fed an atherogenic Western-type diet for 7 weeks. RESULTS: Hematopoietic α7nAChR deficiency clearly increased the number of leukocytes in the peritoneum (2.6-fold, P < 0.001), blood (2.9-fold; P < 0.01), mesenteric lymph nodes (2.0-fold; P < 0.001) and spleen (2.2-fold; P < 0.01), indicative of an increased inflammatory status. Additionally, expression of inflammatory mediators was increased in peritoneal leukocytes (TNFα, 1.6-fold, P < 0.01; CRP, 1.8-fold, P < 0.01) as well as in the spleen (TNFα, 1.6-fold, P < 0.01). The lack of α7nAChR on platelets from these mice increased the expression of active integrin αIIb ß3 upon stimulation by ADP (1.9-fold, P < 0.01), indicating increased activation status, while incubation of human platelets with an α7nAChR agonist decreased aggregation (-35%, P < 0.05). Despite the large effects of hematopoietic α7nAChR deficiency on inflammatory status and platelet function, it did not affect atherosclerosis development or composition of lesions. CONCLUSIONS: Hematopoietic α7nAChR is important for attenuation of inflammatory responses and maintaining normal platelet reactivity, but loss of hematopoietic α7nAChR does not aggravate development of atherosclerosis.
Assuntos
Doenças da Aorta/etiologia , Aterosclerose/etiologia , Plaquetas/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Inflamação/etiologia , Fator de Ativação de Plaquetas , Receptor Nicotínico de Acetilcolina alfa7/deficiência , Animais , Aorta/metabolismo , Aorta/patologia , Doenças da Aorta/sangue , Doenças da Aorta/genética , Doenças da Aorta/patologia , Aterosclerose/sangue , Aterosclerose/genética , Aterosclerose/patologia , Transplante de Medula Óssea , Dieta Ocidental , Modelos Animais de Doenças , Feminino , Genótipo , Transplante de Células-Tronco Hematopoéticas , Inflamação/sangue , Inflamação/genética , Mediadores da Inflamação/sangue , Leucócitos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Placa Aterosclerótica , Receptores de LDL/deficiência , Receptores de LDL/genética , Fatores de Tempo , Receptor Nicotínico de Acetilcolina alfa7/genéticaRESUMO
In a search for genes induced by DNA-damaging agents, we identified two genes that are activated by methyl methanesulfonate (MMS). Expression of both genes is regulated after endoplasmic reticulum (ER) stress via the unfolded protein response (UPR) pathway. The first gene of those identified is the molecular chaperone BiP/GRP78. The second gene, Mif1, is identical to the anonymous cDNA KIAA0025. Treatment with the glycosylation inhibitor tunicamycin both enhances the synthesis of Mif1 mRNA and protein. The Mif1 5' flanking region contains a functional ER stress-responsive element which is sufficient for induction by tunicamycin. MMS, on the other hand, activates Mif1 via an UPR-independent pathway. The gene encodes a 52 kDa protein with homology to the human DNA repair protein HHR23A and contains an ubiquitin-like domain. Overexpressed Mif1 protein is localized in the ER.
Assuntos
Dano ao DNA , Metanossulfonato de Metila/farmacologia , Sequência de Aminoácidos , Linhagem Celular , Clonagem Molecular , Enzimas Reparadoras do DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Humanos , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Dados de Sequência Molecular , Dobramento de Proteína , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Tunicamicina/farmacologiaRESUMO
Apolipoprotein E (apoE), a high affinity ligand for lipoprotein receptors, is synthesized by the liver and extrahepatic tissues, including cells of the monocyte/macrophage cell lineage. The role of monocyte/macrophage-derived apoE in atherogenesis was assessed by transplantation of apoE-deficient (apoE-/-) bone marrow into normolipidemic C57Bl/6 mice. No significant effect could be demonstrated on serum apoE levels in C57Bl/6 mice, transplanted with apoE-deficient bone marrow compared with control transplanted mice. Furthermore, no consistent effect on serum cholesteryl esters and triglyceride concentrations could be demonstrated on either a standard chow diet or a high cholesterol diet. Quantitative analysis of atherosclerosis in mice transplanted with apoE-deficient bone marrow, after two months on a high cholesterol diet, revealed a 4-fold increase in the atherosclerotic lesion area as compared to animals transplanted with apoE+/+ bone marrow. Analysis of the ability of apoE-deficient macrophages to release cholesterol after loading with acetylated LDL revealed that the release of cholesterol from apoE-deficient macrophages was impaired as compared to wild-type macrophages in the absence and the presence of specific cholesterol acceptors. In conclusion, apoE production by macrophages retards the formation of atherosclerotic plaques, possibly by mediating cholesterol efflux. We anticipate that pharmacological approaches to increase apoE synthesis and/or secretion by macrophages might be beneficial for the treatment of atherosclerosis.
Assuntos
Apolipoproteínas E/deficiência , Arteriosclerose/metabolismo , Transplante de Medula Óssea , Macrófagos/metabolismo , Animais , Aorta/metabolismo , Aorta/patologia , Apolipoproteínas E/metabolismo , Arteriosclerose/etiologia , Arteriosclerose/patologia , Colesterol/sangue , Ésteres do Colesterol/sangue , Colesterol na Dieta/administração & dosagem , Feminino , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Quimeras de Transplante , Triglicerídeos/sangueRESUMO
Apolipoprotein E (apoE) is a high affinity ligand for several receptor systems in the liver, including the low-density lipoprotein (LDL) receptor, and non-LDL receptor sites, like the LDL receptor-related protein (LRP), the putative remnant receptor and/or proteoglycans. Although the liver is the major source of apoE synthesis, apoE is also produced by a wide variety of other cell types, including macrophages. In the present study, the role of the LDL receptor in the removal of lipoprotein remnants, enriched with macrophage-derived apoE from the circulation, was determined using the technique of bone marrow transplantation (BMT). Reconstitution of macrophage apoE production in apoE-deficient mice resulted in a serum apoE concentration of only 2% of the concentration in wild-type C57Bl/6 mice. This low level of apoE nevertheless reduced VLDL and LDL cholesterol 12-fold (P<0.001) and fourfold (P<0.001), respectively, thereby reducing serum cholesterol levels and the susceptibility to atherosclerosis. In contrast, reconstitution of macrophage apoE synthesis in mice lacking both apoE and the LDL receptor induced only a twofold (P<0.001) reduction in VLDL cholesterol and had no significant effect on atherosclerotic lesion development, although serum apoE levels were 93% of the concentration in normal C57Bl/6 mice. In conclusion, a functional (hepatic) LDL receptor is essential for the efficient removal of macrophage apoE-enriched lipoprotein remnants from the circulation and thus for normalization of serum cholesterol levels and protection against atherosclerotic lesion development in apoE-deficient mice.
Assuntos
Apolipoproteínas E/fisiologia , Arteriosclerose/prevenção & controle , Colesterol/sangue , Fígado/metabolismo , Macrófagos/metabolismo , Receptores de LDL/fisiologia , Animais , Aorta/patologia , Apolipoproteínas E/biossíntese , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Arteriosclerose/patologia , Medula Óssea/metabolismo , Transplante de Medula Óssea , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout/genética , Receptores de LDL/genéticaRESUMO
Scavenger-receptor class A has been held responsible for the clearance of modified LDL from the blood circulation. However, in mice deficient in scavenger-receptor class A, the decay in vivo of acetylated LDL (t1/2 < 2 min), as well as tissue distribution and liver uptake (at 5 min 77.4 +/- 4.6% of the injected dose) are not significantly different from control mice. The degradation capacity of acetylated LDL with liver endothelial cells, Kupffer cells, and peritoneal macrophages from knock-out mice was 58%, 63%, and 17% of the control, respectively, indicating that scavenger-receptor class A is relatively more important for the degradation of acetylated LDL and foam cell formation in peritoneal macrophages as compared to the liver cell types. This might explain the 60% reduction in atherosclerotic lesion area in scavenger-receptor-deficient apoE knock-out mice as compared to control apoE knock-out mice. Scavenger-receptor BI can facilitate selective uptake of cholesterol esters from HDL. A high cholesterol diet for two weeks induced an 80% downregulation of scavenger-receptor BI in the liver parenchymal cells while expression in liver macrophages is increased fourfold. The in vivo kinetics for the selective uptake of (oxidized) cholesterol esters from HDL correlate with the changes in scavenger-receptor BI expression. It is suggested that scavenger-receptor BI is subject to different regulatory mechanisms in parenchymal liver cells and macrophages related to a difference in function in these cell types.
Assuntos
Arteriosclerose/fisiopatologia , Antígenos CD36/fisiologia , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Proteínas de Membrana , Receptores Imunológicos/fisiologia , Animais , Moléculas de Adesão Celular/fisiologia , Humanos , Fígado/metabolismo , Camundongos , Camundongos Knockout , Receptores Imunológicos/deficiência , Receptores Imunológicos/genética , Receptores de Lipoproteínas/fisiologia , Receptores Depuradores , Receptores Depuradores Classe A , Receptores Depuradores Classe BRESUMO
This study used experience sampling methodology to examine the relationship between stressful daily events and mood. Eighty-five male white-collar workers completed self-reports 10 times a day for 5 days. Controlling for individual differences in mood levels, multilevel regression analyses showed that events were followed by increases in negative affect (NA) and agitation (Ag) and by decreases in positive affect (PA). More unpleasant events were associated with greater changes in all three mood dimensions; controllability mitigated the effects of events on NA and PA. Prior events had persistent effects on current mood. High perceived stress (PS) was associated with greater reactivity of NA and PA to current events, whereas trait anxiety moderated reactivity of Ag. Results indicate that PS is related not only to a higher frequency of reported events but also to more intense and prolonged mood responses to daily stress.
Assuntos
Afeto , Estresse Psicológico/psicologia , Adulto , Ansiedade/psicologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Países Baixos , PersonalidadeRESUMO
Data from a dietary survey of patients in a rehabilitation hospital indicated that their nutrient intake was very low in comparison with the RDAs. Those patients are at risk of developing specific nutritional deficiencies. Recommendations to improve the nutrient intake of this group of elderly persons are given. Even if the "perfect diet" were served, however, a patient's food intake might not be sufficient to meet the RDAs because of lack of appetite or because of elevated requirements owing to various illnesses, multiple drug use, and physiological changes associated with aging. In such a patient, the potentially beneficial use of supplements must be considered.
Assuntos
Hospitalização , Necessidades Nutricionais , Estado Nutricional , Idoso , Ingestão de Energia , Feminino , Humanos , Masculino , Inquéritos Nutricionais , África do SulRESUMO
A Stress Inducing Speech Task was used to investigate the contribution of perceived stress, individual traits, and current mood states to individual differences in salivary cortisol responses. Additionally, we examined the correspondence between laboratory baseline cortisol levels and overall levels in daily life, and between cortisol responses to the speech task and a measure of stress reactivity to stressful events in daily life. Forty-two 'high stress' and forty-five 'low stress' white-collar males completed the speech task and an Experience Sampling study, in which stressful daily events and cortisol levels were monitored for five days. No association was found between perceived stress, trait anxiety, anger, depression, psychosomatic symptoms, coping style or personality and cortisol responses to the speech task. Negative mood state at baseline was associated with higher cortisol levels at baseline just before, and just after, the speech. Laboratory and field cortisol levels were moderately correlated, but no association was found between laboratory and field response measures. Laboratory baseline levels, but not responses to the speech task, were significant predictors of field cortisol levels.
Assuntos
Nível de Alerta/fisiologia , Hidrocortisona/sangue , Individualidade , Estresse Psicológico/complicações , Comportamento Verbal/fisiologia , Adulto , Ritmo Circadiano/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inventário de Personalidade , Meio Social , Estresse Psicológico/sangueRESUMO
Unpredictability of the intensity of an aversive event might be an important factor in producing negative effects of the event, especially if the UCS becomes stronger than could have been expected. The present experiment tested the hypothesis that unpredictability of intensity of a painful stimulus contributes to avoidance behaviour. The experiment was concealed in a shock working-up procedure, which was done to assess the pain level subjects were willing to tolerate in a subsequent experiment. The experimental subjects, who received an unannounced sudden increase of the pain stimulus during the working-up procedure, tolerated less pain on a subjective as well as on an objective level (avoidance of high levels of pain) than the control subjects, who received the stimuli in a predictable pattern. The results support the hypothesis that unpredictability of intensity of an aversive event contributes to avoidance behaviour.
Assuntos
Condicionamento Psicológico , Dor/fisiopatologia , Adulto , Cognição/fisiologia , Condicionamento Psicológico/fisiologia , Método Duplo-Cego , Eletrochoque , Feminino , Habituação Psicofisiológica/fisiologia , Humanos , Dor/psicologia , Medição da Dor , Limiar SensorialRESUMO
In a study of 40 subjects, who twice underwent extensive dental treatment, the relationships between expectations and experiences of pain and of anxiety were investigated. Inaccurate expectations were adjusted in the same way as observed in the laboratory. Especially anxious subjects expected more pain and anxiety than they experienced, and they appeared to need more experiences before their predictions became accurate. In the course of time, the expectations (and memories) of anxious subjects returned to their original more inaccurate level of prediction. The results suggest that the old schema is ultimately reinstated if disconfirmations are few and far between. Anxious subjects did not experience more pain, but they did experience more anxiety than fearless subjects. Detailed investigation of processes of change after disconfirmation showed that anxiety experienced during treatment is a factor that plays a part in maintaining the problem of inaccurate expectations and fear of treatment. Theoretical and clinical implications of these findings are discussed.