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2.
Med Klin Intensivmed Notfmed ; 115(3): 213-221, 2020 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-31197418

RESUMO

BACKGROUND: Endotracheal (ET) intubation has been the gold standard in out-of-hospital airway management for a long time. Recent guidelines suggest an alternative airway management with supraglottic airway devices like the laryngeal tube (LT) especially for less experienced rescue personnel. However, scientific evidence on the prognostic impact of the laryngeal tube in the setting of cardiopulmonary resuscitation is limited. METHODS: We aimed to compare mortality outcomes in out-of-hospital cardiac arrest (OHCA) patients after preclinically initiated airway management with either ET or LT in a propensity score matched, single-center retrospective analysis. RESULTS: A total of 208 patients with OHCA were resuscitated and intubated with either ET (n = 160; 77%) or LT (n = 48; 23%) in the urban area of Frankfurt am Main, Germany, and treated thereafter on the intensive care unit of the University Hospital Frankfurt from 2006-2014. In-hospital mortality was 84% versus 85% in the ET and LT group (p = 0.86). No difference regarding in-hospital mortality has been observed between the two airway management techniques in univariate as well as in multivariate mortality analysis (HR = 0.98, 95% confidence interval [CI] 0.69-1.39; p = 0.92; adjusted HR = 1.01, 95% CI 0.76-1.56; p = 0.62). To adjust for potential confounders, propensity score matching was additionally performed resulting in a cohort of 120 matched patients in a 3:1 ratio (ET:LT). Again, survival to hospital discharge was comparable between the two patient groups (propensity-adjusted HR = 0.99, 95% CI 0.65-1.51, p = 0.97). Further, preclinical airway management with LT or ET showed no difference in mortality within first 24 h (propensity-adjusted HR = 1.02; 95% CI 0.44-2.36; p = 0.96). CONCLUSION: Preclinical airway management with LT shows similar mortality outcomes in direct comparison to intubation with ET in OHCA patients. Further randomized studies are warranted.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar/terapia , Manuseio das Vias Aéreas , Alemanha , Mortalidade Hospitalar , Humanos , Intubação Intratraqueal , Estudos Retrospectivos
3.
Artigo em Inglês | MEDLINE | ID: mdl-31421524

RESUMO

INTRODUCTION: Pentadecanoic (C15:0), heptadecanoic (C17:0) and trans-palmitoleic (t-C16:1n-7) fatty acids (FAs) are often used as biomarkers for dairy fat in adults. This study aimed to investigate the relationship between dairy product intake and these FAs in adolescents. MATERIAL AND METHODS: Healthy adolescents were randomized to one of three groups (Group 1: control; Group 2: consume 3 dairy servings/day; and Group 3: consume ≥ 4 servings/d). C15:0, C17:0 and t-C16:1n-7 were quantified using gas chromatography. Dietary intakes were assessed by 24 h diet recalls. RESULTS: No difference was observed in FAs at baseline or 6 months (mo), however, at 12 mo, erythrocyte C15:0 increased in group 3 (+0.37 µg/ml, p = 0.01). Dairy intake increased in both intervention groups (Group 2: +1.4 servings/d; Group 3: +2.4 servings/d, p < 0.0001) and positively correlated with erythrocyte C15:0 at 12 mo. CONCLUSION: Erythrocyte FAs appear to be associated with increasing dairy intakes during adolescence.


Assuntos
Laticínios , Gorduras na Dieta , Ingestão de Alimentos , Eritrócitos/metabolismo , Ácidos Graxos Monoinsaturados/sangue , Ácidos Graxos/sangue , Adolescente , Biomarcadores , Dieta , Feminino , Humanos , Masculino
4.
Sci Total Environ ; 684: 113-125, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31153061

RESUMO

In forest ecosystems, litter quality is a major driver for soil and understorey characteristics, but elevation, microtopography and subsoil properties may also be important. We tested the importance of each factor in two ancient mixed forests on decalcified marl, dominated by trees with different litter quality such as European hornbeam, with high-palatable litter, and beech, with low-palatable litter. We mapped elevation, differences in local height (microtopography), tree distribution and understorey cover on slopes ranging from crest to bottom, and sampled 200 7 × 7 m grid cells for characteristics of litter input, understorey, topsoil and subsoil. In both forests, elevation decreased gradually, but microtopography showed irregular patterns of depressions and mounds of a few cm below or above average local height. Tree distribution was not affected by elevation or subsoil properties, but clearly by microtopography. Adult beech was abundant on local mounds, while hornbeam was more common in local depressions. Topsoil and understorey characteristics were mainly affected by litter quality (tree species dominance) and microtopography. Litter quality had separate effects from microtopography, but could reinforce this. High litter quality (hornbeam) and low local height both led to high earthworm activity, low litter mass, high erosion, impermeable clay layers close to the surface, high pH, high soil moisture and high diversity of the understorey. Low litter quality (beech) and high local height both led to low earthworm activity, high litter mass, low erosion, low pH, low soil moisture and low plant diversity. Beech and hornbeam may act as ecosystem engineers, which change habitat conditions and local hydrology, and make habitats more suitable to themselves, and/or unsuitable to the other. However, they also increased spatial complexity of the forest and length of the habitat gradient. This may increase forest biodiversity as a whole, but also resilience to prolonged wet or dry periods.


Assuntos
Biodiversidade , Florestas , Dispersão Vegetal , Solo/química , Árvores/fisiologia , Geografia , Luxemburgo
5.
J Thromb Haemost ; 17(1): 63-71, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30565388

RESUMO

Essentials Defective binding to collagen IV has been seen in von Willebrand factor (VWF) A1 domain variants. We developed a murine model of defective VWF-collagen IV interactions with VWF variant p.R1399H. p.1399HH homozygous mice had decreased binding to collagen IV and increased bleeding times. p.1399HH homozygous mice had increased time to thrombosis and decreased platelet adhesion. SUMMARY: Background von Willebrand factor (VWF) binding to type IV collagen occurs via the VWF A1 domain, with p.R1399H being the most common VWF variant affecting this interaction. Objectives We generated a murine model of 1399H VWF to investigate its in vivo effects. Methods Mice expressing the murine 1399H variant were generated via gene targeting in embryonic stem cells. VWF antigen and VWF collagen binding were measured with ELISA. Tail bleeding time assays were performed by clipping a 3-mm segment. Ferric chloride-induced thrombosis was measured via ultrasound in the carotid artery. Platelet aggregation in response to collagens I and IV was measured. VWF-dependent platelet adhesion to collagen IV was measured under flow. Results Breeding of heterozygous p.R1399H and homozygous p.1399HH mice was observed to follow normal Mendelian ratios. No spontaneous bleeding was observed for any of the offspring. VWF expression was normal, but VWF binding to collagen IV was decreased in both heterozygous and homozygous offspring. Blood loss following tail resection was increased for p.1399HH mice, and occlusion times following ferric chloride-induced thrombosis were prolonged. Platelet aggregation was unaffected, but platelet adhesion to collagen IV under flow was diminished for p.1399HH mice. Conclusions These results show that a decrease in the ability of 1399H VWF to bind collagen IV under static conditions corresponds to a decrease in binding under flow conditions, an increased bleeding time, and a prolonged time to thrombosis. This study supports the potential for a bleeding phenotype in patients with aberrant VWF-collagen IV binding.


Assuntos
Colágeno Tipo IV/metabolismo , Hemorragia/sangue , Hemostasia , Adesividade Plaquetária , Doenças de von Willebrand/sangue , Fator de von Willebrand/metabolismo , Animais , Modelos Animais de Doenças , Hemorragia/genética , Homozigoto , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Agregação Plaquetária , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Doenças de von Willebrand/genética , Fator de von Willebrand/genética
6.
Osteoporos Int ; 29(9): 1933-1948, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29740667

RESUMO

A summary of systematic reviews and meta-analyses addressing the benefits and risks of dietary protein intakes for bone health in adults suggests that dietary protein levels even above the current RDA may be beneficial in reducing bone loss and hip fracture risk, provided calcium intakes are adequate. Several systematic reviews and meta-analyses have addressed the benefits and risks of dietary protein intakes for bone health in adults. This narrative review of the literature summarizes and synthesizes recent systematic reviews and meta-analyses and highlights key messages. Adequate supplies of dietary protein are required for optimal bone growth and maintenance of healthy bone. Variation in protein intakes within the "normal" range accounts for 2-4% of BMD variance in adults. In older people with osteoporosis, higher protein intake (≥ 0.8-g/kg body weight/day, i.e., above the current RDA) is associated with higher BMD, a slower rate of bone loss, and reduced risk of hip fracture, provided that dietary calcium intakes are adequate. Intervention with dietary protein supplements attenuate age-related BMD decrease and reduce bone turnover marker levels, together with an increase in IGF-I and a decrease in PTH. There is no evidence that diet-derived acid load is deleterious for bone health. Thus, insufficient dietary protein intakes may be a more severe problem than protein excess in the elderly. Long-term, well-controlled randomized trials are required to further assess the influence of dietary protein intakes on fracture risk.


Assuntos
Proteínas Alimentares/administração & dosagem , Osteoporose/prevenção & controle , Equilíbrio Ácido-Base/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Cálcio da Dieta/administração & dosagem , Proteínas Alimentares/efeitos adversos , Proteínas Alimentares/farmacologia , Humanos , Fraturas por Osteoporose/prevenção & controle , Medição de Risco/métodos
7.
Hum Reprod ; 32(11): 2332-2339, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28927238

RESUMO

STUDY QUESTION: Is the thrombophilia mutation factor V Leiden (FVL) associated with an increased total sperm count? SUMMARY ANSWER: Carriers of FVL have a higher total sperm count than non-FVL-carriers, which could not be explained by genetic linkage or by observations in a FVL-mouse model. WHAT IS KNOWN ALREADY: FVL has a high prevalence in Caucasians despite detrimental health effects. Carriers have been shown to have higher fecundity, which might partly explain this evolutionary paradox. STUDY DESIGN, SIZE, DURATION: We determined FVL status in two cohorts (Dutch, n = 627; Danish, n = 854) of consecutively included men without known causes for spermatogenic failure, and performed an individual patient data meta-analysis of these two cohorts together with one previously published (Dutch, n = 908) cohort. We explored possible biological underpinnings for the relation between sperm count and FVL, by use of a FVL-mouse model and investigations of genetic linkage. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were male partners of subfertile couples (two Dutch cohorts) and young men from the general population (Danish cohort): FVL carrier rate was 4.0%, 4.6% and 7.3%, respectively. There were differences in smoking, abstinence time and age between the cohorts. We corrected for these in the primary analysis, which consisted of a mixed linear effects model, also incorporating unobjectified population differences. In public haplotype data from subjects of European descent, we explored linkage disequilibrium of FVL with all known single nucleotide polymorphisms in a 1.5 MB region around the F5 gene with an R2 cutoff of 0.8. We sequenced exons of four candidate genes hypothesized to be linked to FVL in a subgroup of FVL carriers with extreme sperm count values. The animal studies consisted of never mated 15-18-week-old C57BL/J6 mice heterozygous and homozygous for FVL and wild-type mice. We compared spermatogenesis parameters (normalized internal genitalia weights, epididymis sperm content and sperm motility) between FVL and wild-type mice. MAIN RESULTS AND THE ROLE OF CHANCE: Human FVL carriers have a higher total sperm count than non-carriers, with an adjusted mean difference of 31 × 106 (95%CI 0.2-61.7; P = 0.048). Mice with the FVL mutation do not have increased spermatogenesis as compared to wildtype mice. None of the studied polymorphisms was in linkage disequilibrium, either in the public databases or in a subgroup of FVL carriers with extremely high sperm counts. LIMITATIONS, REASONS FOR CAUTION: The difference in total sperm count would benefit from confirmation in other cohorts. The finding of higher count in carriers was consistent however, with no heterogeneity between the cohorts. The lack of effect of murine FVL might suggest there is no direct causality. The exploratory efforts on genetic linkage do not rule out that the association is a reflection of FVL co-inheritance with a non-studied causative polymorphism. WIDER IMPLICATIONS OF THE FINDINGS: A high sperm count in FVL-carrying males contributes to understanding the high prevalence of this otherwise disadvantageous mutation. The findings might provide directions for future research on male fertility. STUDY FUNDING/COMPETING INTEREST(S): No conflicts of interest. Research was conducted with funding from the Netherlands Organisation for Scientific Research (NWO, VIDI innovative research grant 016.126.364 awarded to S. Middeldorp). The Danish cohort was supported by the Innovation Fund Denmark (InnovationsFonden, grant no. 14-2013-4), The Danish Ministry of Health and the Danish Environmental Protection Agency. TRIAL REGISTRATION NUMBER: Not applicable.


Assuntos
Fator V/genética , Infertilidade Masculina/genética , Contagem de Espermatozoides , Motilidade dos Espermatozoides/genética , Adolescente , Adulto , Animais , Humanos , Masculino , Camundongos Endogâmicos C57BL , Análise do Sêmen , Adulto Jovem
8.
Int J Obes (Lond) ; 41(5): 776-782, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28163319

RESUMO

BACKGROUND/OBJECTIVES: Infant complementary feeding is important for establishing food preferences. Few studies exist on the effects of infant complementary feeding choices (food preparation methods) on dietary intake, growth or adiposity. We examined whether provision of homemade complementary food is associated with the development of dietary diversity, nutrient intakes and quality of infant growth. SUBJECTS/METHODS: Secondary analysis of feeding practices from a randomized trial of vitamin D supplementation in 132 healthy breastfed 1-month-old infants from Montréal, Canada. This longitudinal study used diet records, anthropometric and body composition data (dual-energy X-ray absorptiometry) from assessments that occurred when infants were 6, 9, 12 and 36 months of age. Infants were grouped into three categories of food preparation method on the basis of whether or not they had consumed homemade or commercial meat or fruit and vegetable by 9 months (homemade, commercial and both). Multivariable regression controlled for family income, maternal education and infant sex. RESULTS: Dietary data were available for 65 infants. By 9 months, 22% of infants had exclusively received homemade (n=14), 14 infants had exclusively received commercial and 37 infants had received both. The development of dietary diversity (number of World Health Organization-recommended food groups) was higher (0.76 (95% confidence interval (CI): 0.14, 1.38); P<0.05) in the homemade group versus commercial. Energy and nutrient intakes did not differ by group over time. The homemade group had 773 g (-1364, -182; P<0.01) lower whole-body fat mass and 7.1% (-12.6, -1.6; P<0.05) lower % body fat at 12 months compared with the reference group (both homemade and commercial). Reduced whole-body fat mass in the homemade group persisted at 36 months (-696 g (95% CI: -1341, -52); P<0.05). There were no differences between groups for changes in growth Z-scores (length-for-age, weight-for-age and body mass index-for-age). CONCLUSIONS: Provision of homemade complementary food is associated with increased dietary diversity during the first year of life and reduced adiposity.


Assuntos
Adiposidade/fisiologia , Aleitamento Materno , Dieta/estatística & dados numéricos , Alimentos Infantis , Fenômenos Fisiológicos da Nutrição do Lactente , Aumento de Peso/fisiologia , Peso Corporal , Canadá , Proteínas Alimentares , Ingestão de Energia/fisiologia , Comportamento Alimentar , Feminino , Frutas , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Carne , Verduras
9.
Pediatr Obes ; 12(1): 38-47, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-26843140

RESUMO

BACKGROUND: The impact of vitamin D status on body composition is not well understood. OBJECTIVES: Evaluate how vitamin D supplementation in infancy affects body composition at 3 years of age. METHODS: Double-blind randomized trial of 132, 1-month-old healthy, breastfed infants randomly assigned to receive oral vitamin D3 supplements of 400, 800, 1200 or 1600 IU d-1 for 11 months. In the present analysis, 87 (66%) returned at 3 years of age. Body composition was measured using dual-energy x-ray absorptiometry and plasma 25-hydroxyvitamin D [25(OH)D] concentrations by liquid chromatography tandem mass spectrometry. RESULTS: Anthropometry, body composition, diet, activity and demographics were similar across dosage groups at 3 years. Mean 25(OH)D concentration from 1 month to 3 years was higher (P < 0.001) in the 1200 IU group than 800 and 400 IU groups. Children with 25(OH)D concentrations above 75 nmol L-1 had lower fat mass (~450 g; P = 0.049). In multiple linear regression, mean 25(OH)D was associated with lean mass percent (ß = 0.06; CI: 0.00, 0.12; P = 0.042), fat mass (ß = -11.29; CI: -22.06, -0.52; P = 0.048) and body fat percent (ß = -0.06; CI: -0.12, -0.01; P = 0.045). CONCLUSIONS: Higher vitamin D status from infancy through to 3 years of age associates with leaner body composition.


Assuntos
Composição Corporal/efeitos dos fármacos , Colecalciferol/uso terapêutico , Absorciometria de Fóton , Antropometria , Canadá , Pré-Escolar , Cromatografia Líquida , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Lactente , Masculino , Espectrometria de Massas , Estudos Prospectivos , Vitamina D/análogos & derivados , Vitamina D/sangue
10.
J Thromb Haemost ; 15(1): 98-109, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27496751

RESUMO

Essentials Platelet-Factor (F) VIII gene therapy is a promising treatment in hemophilia A. This study aims to evaluate if platelet-FVIII expression would increase the risk for thrombosis. Targeting FVIII expression to platelets does not induce or elevate thrombosis risk. Platelets expressing FVIII are neither hyper-activated nor hyper-responsive. SUMMARY: Background Targeting factor (F) VIII expression to platelets is a promising gene therapy approach for hemophilia A, and is successful even in the presence of inhibitors. It is well known that platelets play important roles not only in hemostasis, but also in thrombosis and inflammation. Objective To evaluate whether platelet-FVIII expression might increase thrombotic risk and thereby compromise the safety of this approach. Methods In this study, platelet-FVIII-expressing transgenic mice were examined either in steady-state conditions or under prothrombotic conditions induced by inflammation or the FV Leiden mutation. Native whole blood thrombin generation assay, rotational thromboelastometry analysis and ferric chloride-induced vessel injury were used to evaluate the hemostatic properties. Various parameters associated with thrombosis risk, including D-dimer, thrombin-antithrombin complexes, fibrinogen, tissue fibrin deposition, platelet activation status and activatability, and platelet-leukocyte aggregates, were assessed. Results We generated a new line of transgenic mice that expressed 30-fold higher levels of platelet-expressed FVIII than are therapeutically required to restore hemostasis in hemophilic mice. Under both steady-state conditions and prothrombotic conditions induced by lipopolysaccharide-mediated inflammation or the FV Leiden mutation, supratherapeutic levels of platelet-expressed FVIII did not appear to be thrombogenic. Furthermore, FVIII-expressing platelets were neither hyperactivated nor hyperactivatable upon agonist activation. Conclusion We conclude that, in mice, more than 30-fold higher levels of platelet-expressed FVIII than are required for therapeutic efficacy in hemophilia A are not associated with a thrombotic predilection.


Assuntos
Fator VIII/metabolismo , Terapia Genética/métodos , Hemofilia A/genética , Hemofilia A/terapia , Trombose/genética , Animais , Antitrombinas/metabolismo , Coagulação Sanguínea/genética , Plaquetas/metabolismo , Coagulantes/uso terapêutico , Fator V/genética , Fator VIII/genética , Fibrina/metabolismo , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Fibrinogênio/metabolismo , Hemostasia , Humanos , Leucócitos/metabolismo , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Fenótipo , Ativação Plaquetária , Trombina/metabolismo
11.
Osteoporos Int ; 27(8): 2459-66, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26968165

RESUMO

UNLABELLED: Whether infant vitamin D supplementation may have long-term bone benefits is unclear. In this study, breastfed infants who received vitamin dosages greater than 400 IU/day did not have higher bone mineralization at 3 years. This study provides important data to inform pediatric public health recommendations for vitamin D. INTRODUCTION: North American health agencies recommend breastfed infants should be supplemented with 400 IU of vitamin D/day to support bone health. Few studies examined the long-term benefits of early life vitamin D supplementation on bone mineralization. The objective of this study was to determine if a dose-response relationship exists between infant vitamin D supplementation, vitamin D status, and bone outcomes at 3 years of age. METHODS: This was a double-blind randomized trial of 132, 1-month-old healthy, breastfed infants from Montréal, Canada, between 2007 and 2010. In this longitudinal analysis, 87 infants (66 %) returned for follow-up at 3 years of age, between 2010 and 2013. At 1 month of age, participants were randomly assigned to receive oral cholecalciferol (vitamin D3) supplements of 400, 800, 1200, or 1600 IU/day until 12 months of age. Lumbar spine vertebrae 1-4 (LS) bone mineral density (BMD), LS and whole body bone mineral content (BMC), and mineral accretion were measured by dual-energy x-ray absorptiometry at 3 years. RESULTS: At follow-up, the treatment groups were similar in terms of diet, sun exposure, and demographics. There were no significant differences among the groups in LS or whole body BMC, BMD, or accretion. Although, 25(OH)D concentrations were not different among the groups, higher doses (1200 and 1600 IU/day) achieved higher 25(OH)D area under the curve from 1 to 36 months vs. 400 IU/day. CONCLUSIONS: This is the first longitudinal follow-up of an infant vitamin D dose-response study which examines bone mineralization at 3 years of age. Dosages higher than 400 IU/day do not appear to provide additional benefits to the bone at follow-up. Larger studies with more ethnically diverse groups are needed to confirm these results.


Assuntos
Densidade Óssea , Colecalciferol/administração & dosagem , Suplementos Nutricionais , Vitamina D/análogos & derivados , Aleitamento Materno , Canadá , Pré-Escolar , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Lactente , Masculino , Vitamina D/sangue
12.
J Thromb Haemost ; 13(12): 2210-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26453193

RESUMO

BACKGROUND: We have recently developed a successful gene therapy approach for hemophilia A in which factor VIII (FVIII) expression is targeted to platelets by the αIIb promoter. Levels of platelet-expressed FVIII (2bF8) achieved by gene therapy may vary between individuals due to differences in ex vivo transduction and gene expression efficiency. Accurate assays to evaluate 2bF8 efficacy are desirable. OBJECTIVE: To compare the hemostatic efficacy of 2bF8 with replacement therapy over a wide therapeutic dose range. METHODS: Efficacy of 2bF8 was assessed using a new transgenic mouse model expressing high 2bF8 levels (LV18(tg) ). Blood from LV18(tg) mice or FVIII(null) mice infused with recombinant FVIII was mixed with FVIII(null) blood at different ratios ex vivo to achieve several concentrations of 2bF8 or plasma FVIII. Samples were evaluated with a novel native whole blood thrombin generation assay that uses recalcified whole blood without the addition of tissue factor to initiate coagulation. RESULTS: FVIII dose dependency was observed in all five thrombin generation parameters. While the total amount of thrombin generated was similar, 2bF8 significantly accelerated thrombin generation compared with plasma FVIII. Remarkably, a 10-fold lower dose of 2bF8 than plasma FVIII (0.2% vs. 2%) significantly shortened the onset and peak of thrombin generation compared with FVIII(null) blood. CONCLUSION: Using a new transgenic mouse model, we showed that the novel native whole blood thrombin generation assay established here can be used to monitor platelet targeted FVIII gene therapy. The higher therapeutic efficacy of 2bF8 compared with factor replacement therapy seemed to be due to acceleration of thrombin generation.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Coagulantes/farmacologia , Fator VIII/biossíntese , Fator VIII/farmacologia , Animais , Coagulação Sanguínea/genética , Testes de Coagulação Sanguínea , Relação Dose-Resposta a Droga , Fator VIII/genética , Genótipo , Humanos , Cinética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Fenótipo , Glicoproteína IIb da Membrana de Plaquetas/genética , Regiões Promotoras Genéticas , Proteínas Recombinantes/farmacologia , Trombina/metabolismo
13.
J Thromb Haemost ; 13(6): 1073-80, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25690763

RESUMO

BACKGROUND: The high allelic frequency of the prothrombotic Leiden polymorphism in human blood coagulation factor V (FV) has been speculated to reflect positive selection during evolution. Heterozygous Leiden carriers enrolled in the placebo arm of the PROWESS sepsis trial and heterozygous Leiden mice challenged with endotoxin both showed reduced mortality, whereas homozygous Leiden mice were not protected from lethal endotoxemia. Follow-up analyses of clinical outcomes and of mouse models of infection with various pathogens remained inconclusive. OBJECTIVE: To establish whether activated protein C resistance of FV Leiden modifies the outcome of bacterial infection in murine sepsis models. METHODS: Homozygous and heterozygous FV Leiden mice were subjected to gram-positive (S. aureus) or gram-negative (Y. pestis; E. coli) septic peritonitis or polymicrobial, focal septic peritonitis induced by cecal ligation and puncture. The effect of FV Leiden on 7-day survival and bacterial dissemination was assessed. Outcomes were compared with the sepsis survival of mice with genetically impaired hemostasis (hemophilia A, thrombocytopenia, thrombin receptor PAR4 [protease activated receptor 4] deficiency, endothelial protein C receptor [ProcR/EPCR] deficiency). RESULTS: Heterozygous, but not homozygous, Leiden mice were protected from lethal infection with highly virulent S. aureus and Y. pestis strains. FV Leiden did not affect the outcome of sepsis induced by cecal ligation and puncture, staphylokinase-deficient S. aureus, Pla-deficient Y. pestis, or E. coli. Thrombocytopenia, deficiency of PAR1 or PAR4 did not affect S. aureus sepsis survival, whereas hemophilia A increased mortality. ProcR deficiency selectively abolished the survival advantage of heterozygous Leiden mice. CONCLUSIONS: In mice, heterozygous FV Leiden carriers are protected from sepsis mortality after infection with clinically relevant human bacterial pathogens.


Assuntos
Resistência à Proteína C Ativada/genética , Fator V/metabolismo , Heterozigoto , Sepse/genética , Resistência à Proteína C Ativada/sangue , Animais , Translocação Bacteriana , Coagulação Sanguínea , Plaquetas/metabolismo , Plaquetas/microbiologia , Modelos Animais de Doenças , Receptor de Proteína C Endotelial , Escherichia coli/patogenicidade , Infecções por Escherichia coli/sangue , Infecções por Escherichia coli/microbiologia , Fator V/genética , Fibrinólise , Genótipo , Homozigoto , Humanos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Peritonite/sangue , Peritonite/microbiologia , Fenótipo , Peste/sangue , Peste/microbiologia , Fatores de Proteção , Receptor PAR-1/genética , Receptor PAR-1/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Receptores de Trombina/genética , Receptores de Trombina/metabolismo , Fatores de Risco , Sepse/sangue , Sepse/microbiologia , Infecções Estafilocócicas/sangue , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/patogenicidade , Fatores de Tempo , Yersinia pestis/patogenicidade
14.
Regul Toxicol Pharmacol ; 70 Suppl 1: S81-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25455220

RESUMO

The biological activity of mainstream smoke from experimental kretek cigarettes with and without three mixes of ingredients was assessed in a 90-day rat inhalation study and in a 4-day in vivo micronucleus assay. 350 ingredients, commonly used in various combinations and in a limited number in a given brand in the manufacture of marketed kretek cigarettes, were applied at a low and a high target level to test cigarettes with a typical Indonesian blend of tobaccos and cloves. In the 90-day inhalation study, effects commonly seen in rat inhalation studies with mainstream smoke were observed. In general, no ingredients-related histopathological changes were found in the respiratory tract. In the 4-day micronucleus assay exposure of male rats to mainstream smoke from the test cigarettes containing any of the three mixes did not increase the proportions of micronucleated cells in peripheral blood and bone marrow over the proportion of micronucleated cells in the control group. Based on the results of these studies, it can be concluded that the addition of ingredients commonly used in the manufacture of kretek cigarettes did not change the overall in vivo toxicity profile of the mainstream smoke.


Assuntos
Sistema Respiratório/efeitos dos fármacos , Fumaça/efeitos adversos , Syzygium , Produtos do Tabaco/toxicidade , Administração por Inalação , Animais , Carboxihemoglobina/análise , Feminino , Masculino , Testes para Micronúcleos , Nicotina/metabolismo , Fenômenos Fisiológicos Respiratórios/efeitos dos fármacos , Sistema Respiratório/patologia , Testes de Toxicidade Subcrônica
15.
Regul Toxicol Pharmacol ; 70 Suppl 1: S26-40, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25455226

RESUMO

A typical Indonesian kretek cigarette brand and an experimental kretek reference cigarette were compared to the reference cigarette 2R4F in two 90-day inhalation studies. Male and female rats were exposed nose-only to mainstream smoke for 6 hours daily, for 90 consecutive days. Biological endpoints were assessed according to OECD guideline 413, with special emphasis on respiratory tract histopathology and on lung inflammation (broncho-alveolar lavage fluid levels of neutrophils, macrophages and lymphocytes). Histopathological alterations included: in the nose, hyperplasia and squamous metaplasia of the respiratory epithelium and squamous metaplasia and atrophy of the olfactory epithelium; in the larynx, epithelial squamous metaplasia and hyperplasia; in the lungs, accumulation of macrophages in alveoli and goblet cell hyperplasia in bronchial epithelium. The findings were qualitatively consistent with observations from previous similar studies on conventional cigarettes. Compared to 2R4F cigarette, however, kretek smoke exposure was associated with a pronounced attenuation of pulmonary inflammation and less severe histopathological changes in the respiratory tract. Neutrophilic inflammation was also significantly lower (>70%). These results are consistent with the observations made on smoke chemistry and in vitro toxicology. They do not support any increased toxicity of the smoke of kretek cigarettes compared to conventional American-blended cigarettes.


Assuntos
Fumaça/efeitos adversos , Syzygium , Produtos do Tabaco/toxicidade , Administração por Inalação , Animais , Peso Corporal/efeitos dos fármacos , Líquido da Lavagem Broncoalveolar/citologia , Carboxihemoglobina/análise , Contagem de Células , Feminino , Irritantes/toxicidade , Masculino , Nicotina/metabolismo , Ratos , Ratos Sprague-Dawley , Sistema Respiratório/efeitos dos fármacos , Sistema Respiratório/patologia , Sistema Respiratório/fisiopatologia , Testes de Toxicidade Subcrônica
16.
Regul Toxicol Pharmacol ; 70 Suppl 1: S54-65, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25455231

RESUMO

The biological effects of mainstream smoke (MS) from Indonesian-blended cigarettes with and without added cloves, cloves extracted with hot ethanol, and extracted cloves replenished with eugenol or clove oil were assessed in a 90-day inhalation study in rats. A separate 35-day inhalation study in rats was performed with MS from American-blended cigarettes with 0%, 2.5%, 5% or 10% added eugenol. Effects commonly seen in inhalation studies with MS were observed. These included histopathological changes indicative of irritation in the entire respiratory tract and inflammatory responses in the lung. Adding cloves to American- or Indonesian-blended cigarettes reduced the inflammatory response in the lung but with no difference between the two blend types. When the clove oil was extracted (∼ 75% reduction of eugenol achieved) from cloves, the inflammatory response in the lung was still reduced similarly to whole cloves but the severity of histopathological changes in the upper respiratory tract was less reduced. Add back of clove oil or pure eugenol reduced this response to a level similar to what was seen with whole cloves. When eugenol was added to American-blended cigarettes, similar findings of reduced lung inflammation and severity of histopathological changes in respiratory the tract was confirmed. These studies demonstrate a clear effect of cloves, and in particular eugenol, in explaining these findings.


Assuntos
Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Óleo de Cravo/toxicidade , Eugenol/toxicidade , Fumaça/efeitos adversos , Produtos do Tabaco/toxicidade , Administração por Inalação , Animais , Carboxihemoglobina/análise , Contagem de Células , Citocinas/metabolismo , Feminino , Masculino , Nicotina/metabolismo , Pneumonia/patologia , Pneumonia/fisiopatologia , Ratos Sprague-Dawley , Sistema Respiratório/efeitos dos fármacos , Sistema Respiratório/patologia , Sistema Respiratório/fisiopatologia , Syzygium
17.
Artigo em Inglês | MEDLINE | ID: mdl-24928793

RESUMO

Long chain PUFA enhance bone mass in non-pregnant mammals. We examined the effects of arachidonic (AA; 20:4n-6) and docosahexaenoic (DHA; 22:6n-3) acid on bone mass of mothers and neonates. Guinea pig sows (n=15) were fed control, DHA or AA+DHA diets from mating to weaning. Measurements included: osteocalcin (OC), deoxypyridinoline (DPD), areal bone mineral density (aBMD) in sows and neonates; and volumetric density (vBMD) in neonates. Only vertebral aBMD and OC:DPD ratio declined during reproduction and only DHA reduced OC:DPD. Male pup weight was reduced by DHA and female weight elevated by AA+DHA. Whole body and femur aBMD were reduced by DHA and AA+DHA; whereas tibia vBMD was reduced by DHA in males. Female whole body, tibia and vertebrae aBMD plus tibia vBMD were elevated by AA+DHA; and DHA elevated whole body, tibia and vertebrae aBMD. Dietary AA+DHA and DHA elicit sex-dependent effects on neonatal bone, with minimal impact on mothers.


Assuntos
Ácido Araquidônico/administração & dosagem , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/administração & dosagem , Fêmur/efeitos dos fármacos , Reprodução , Coluna Vertebral/efeitos dos fármacos , Tíbia/efeitos dos fármacos , Aminoácidos/metabolismo , Animais , Animais Recém-Nascidos , Peso Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Feminino , Fêmur/crescimento & desenvolvimento , Feto , Cobaias , Masculino , Osteocalcina/metabolismo , Gravidez , Fatores Sexuais , Coluna Vertebral/crescimento & desenvolvimento , Tíbia/crescimento & desenvolvimento , Desmame
18.
J Thromb Haemost ; 12(1): 71-81, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24175924

RESUMO

BACKGROUND: Tumor cell tissue factor (TF)-initiated coagulation supports hematogenous metastasis by fibrin formation, platelet activation and monocyte/macrophage recruitment. Recent studies identified host anticoagulant mechanisms as a major impediment to successful hematogenous tumor cell metastasis. OBJECTIVE: Here we address mechanisms that contribute to enhanced metastasis in hyperthrombotic mice with functional thrombomodulin deficiency (TM(Pro) mice). METHODS: Pharmacological and genetic approaches were combined to characterize relevant thrombin targets in a mouse model of experimental hematogenous metastasis. RESULTS: TF-dependent, but contact pathway-independent, syngeneic breast cancer metastasis was associated with marked platelet hyperreactivity and formation of leukocyte-platelet aggregates in immune-competent TM(Pro) mice. Blockade of CD11b or genetic deletion of platelet glycoprotein Ibα excluded contributions of these receptors to enhanced platelet-dependent metastasis in hyperthrombotic mice. Mice with very low levels of the endothelial protein C receptor (EPCR) did not phenocopy the enhanced metastasis seen in TM(Pro) mice. Genetic deletion of the thrombin receptor PAR1 or endothelial thrombin signaling targets alone did not diminish enhanced metastasis in TM(Pro) mice. Combined deficiency of PAR1 on tumor cells and the host reduced metastasis in TM(Pro) mice. CONCLUSIONS: Metastasis in the hyperthrombotic TM(Pro) mouse model is mediated by platelet hyperreactivity and contributions of PAR1 signaling on tumor and host cells.


Assuntos
Metástase Neoplásica , Trombina/metabolismo , Tromboplastina/metabolismo , Trombose/patologia , Animais , Sequência de Bases , Linhagem Celular Tumoral , Primers do DNA , Camundongos , Camundongos Endogâmicos C57BL , Ativação Plaquetária , Reação em Cadeia da Polimerase , Trombose/metabolismo
19.
Int J Obes (Lond) ; 38(1): 1-10, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23828100

RESUMO

The prevalence of excess weight in children and adults worldwide has increased rapidly in the last 25 years. Obesity is positively associated with increased risk for many health issues such as type 2 diabetes, cardiovascular disease and psychosocial problems. This review focuses on child populations, as it is known that the sedentary behaviors of overweight/obese youth often endure into adulthood. Assessment of physical activity (PA), among other factors such as diet and socio-economic status, is important in understanding weight variation and in designing interventions. This review highlights common subjective and objective PA assessment tools, the validity of these methods and acceptable ways of collecting and interpreting PA data. The aim is to provide an update on PA assessment in overweight/obese children, highlighting current knowledge and any gaps in the literature, in order to facilitate the use of PA assessments and interventions by health-care professionals as well as suggest future research in this area.


Assuntos
Acelerometria/métodos , Dieta , Exercício Físico , Comportamentos Relacionados com a Saúde , Obesidade Infantil/prevenção & controle , Comportamento Sedentário , Adolescente , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Obesidade Infantil/epidemiologia , Prevalência , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Autorrelato , Classe Social
20.
Hamostaseologie ; 31(3): 185-95, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21826371

RESUMO

The central effector protease of the protein C pathway, activated protein C (APC), interacts with the endothelial cell protein C receptor, with protease activated receptors (PAR), the apolipoprotein E2 receptor, and integrins to exert multiple effects on haemostasis and immune cell function. Such receptor interactions modify the activation of PC and determine the biological response to endogenous and therapeutically administered APC. This review summarizes the current knowledge about interactions of APC with cell surface-associated receptors, novel substrates such as histones and tissue factor pathway inhibitor, and their implications for the biologic function of APC in the control of coagulation and inflammation.


Assuntos
Fatores de Coagulação Sanguínea/imunologia , Coagulação Sanguínea/imunologia , Endotélio Vascular/imunologia , Hemostasia/imunologia , Proteína C/imunologia , Receptores de Superfície Celular/imunologia , Animais , Humanos
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