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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Prática em transfusão de glóbulos vermelhos e índice de oxigenação em um centro de terapia intensiva pediátrico / Red blood cell transfusion practice and oxygenation index in a pediatric intensive care unit.

Cibele Mendes 06 August 2007 (has links)
A anemia é a causa primária de indicação de transfusão de glóbulos vermelhos e é especialmente prevalente e esperada em centros de terapia intensiva. Os benefícios das transfusões incluem aumento da oxigenação tissular, diminuição de hemorragias, tratamento da anemia e da hipovolemia. Os poucos estudos publicados têm demonstrado variações significativas nas práticas de transfusões de glóbulos vermelhos e o melhor momento para a indicação destas transfusões ainda não foi identificado. Objetivos Descrever a população de crianças que recebeu transfusão de glóbulos vermelhos com relação à faixa etária, concentração de hemoglobina (Hb) e taxa de hematócrito (HT), uso de saturação venosa central de oxigênio (SvO2), lactato sérico arterial, procedimentos terapêuticos e presença de disfunção de múltiplos órgãos e sistemas (DMOS). Métodos Estudo retrospectivo observacional, realizado no Centro de Terapia Intensiva Pediátrico (CTIP) do Instituto da Criança da Faculdade de Medicina da Universidade de São Paulo, em 2004, com crianças que receberam transfusão de glóbulos vermelhos. Descrevemos o número de pacientes, faixa etária, motivo de internação no CTIP, presença de doença de base e de DMOS, uso de SvO2, lactato sérico arterial, Hb, HT e procedimentos terapêuticos (ventilação mecânica, drogas vasoativas e métodos de substituição renal). Resultados A transfusão de glóbulos vermelhos foi realizada em 50% dos pacientes internados. A idade mediana foi de 18 meses e o principal motivo de internação foi insuficiência respiratória (35% dos casos). Doença de base estava presente em 84% dos casos e DMOS em 47% dos casos. Foram realizadas coletas de Hb e HT em todos os casos e de SvO2 e lactato sérico arterial em 24% dos casos. A mediana de Hb pré-transfusional foi de 7,8 g/dl. Os pacientes transfundidos estavam sendo submetidos a algum procedimento terapêutico em 82% dos casos. Conclusões São realizadas transfusões de glóbulos vermelhos em todas as idades. A concentração de hemoglobina e a taxa de hematócrito são os principais dados utilizados para a indicação destas transfusões. O lactato sérico arterial e a SvO2 são pouco utilizados para se indicar a transfusão de glóbulos vermelhos. A maioria dos pacientes transfundidos recebe algum procedimento terapêutico e, em muitos casos, são realizadas transfusões em pacientes que apresentam DMOS. / Anemia is the primary cause of red blood cell transfusions and it is especially prevalent and even expected in critical care settings. The benefits of red blood cell transfusions include increase in tissue oxygenation, treatment of anemia and hypovolemia. There are substantial variations in transfusion practices and the optimal transfusion practice for various types of critically ill patients with anemia has not been established. Objectives To describe the clinical, hematological and therapeutic characteristics of children who received red blood cell transfusion in a Pediatric Intensive Care Unit (PICU). Methods Retrospective observational study, performed in the PICU of ?Instituto da Criança?, Medicine School of University of São Paulo, in 2004, with one hundred children who received red blood cell transfusion. We described the number of patients included in the study, age, reason for admission to the PICU, presence of baseline illness and multiple organ system failure (MODS), use of oxygen central venous saturation, arterial lactate, hemoglobin concentration (Hb), hematocrit (HT) and therapeutics procedures (mechanical ventilation, use of vasoactive drugs and renal replacement methods). Results The red blood cell transfusion occurred in 50% of the patients. Median age of patients was 18 months. The most common reason for admission was respiratory failure, in 35% of the cases. Baseline illness was present in 84% of the cases and MODS in 47% of the cases. Hb and HT were collected in all the cases and oxygen central venous saturation and arterial lactate were collected in 24% of the cases. The median pre-transfusion hemoglobin concentration was 7.8 g/dl. The patients were receiveing therapeutics procedures in 82% of the cases. Conclusions Red blood cell transfusions are performed in children of all ages. The hemoglobin concentration and hematocrit are the main reason to indicate the red blood cell transfusion. Arterial lactate and oxygen central venous saturation are rarely utilized. The majority of patients receive therapeutic procedures and, in many cases, patients with MODS are given red blood cell transfusions.
32

Interação de porfirinas hidrofílicas e de hemoglobina extracelular com modelos biomiméticos de membrana biológica / Interaction of hidrophilic porphyrins and extracellular hemoglobin with biomimetic models of biological membranes

Patricia Soares Santiago 04 April 2008 (has links)
Na primeira parte deste trabalho foi estudada a interação da porfirina catiônica meso-tetrakis N-metil-4-piridil (TMPyP) e a porfirina aniônica meso-tetrakis 4-fenilsulfonato (TPPS4) nas formas de base livre com sistemas modelos de membrana biológica (micelas iônicas, micelas mistas e vesículas de fosfolipídios) em soluções aquosas, através das técnicas de absorção ótica, espalhamento de luz ressonante (RLS do inglês \"resonante light scattering), fluorescência e SAXS, do inglês \"Small Angle X-Ray Scattering\". As curvas de SAXS das micelas catiônicas de CTAC (cloreto de cetiltrimetilamônio) foram ajustadas como um elipsóide prolato na ausência e na presença de 2-10 mM de TPPS4. Os dados de SAXS mostraram que a presença da porfirina TPPS4 modifica o centro hidrofóbico micelar, levando a formação de micelas menores. Através das análises dos dados de SAXS das micelas de SDS (dodecilsulfato de sódio) observamos que a forma da micela na ausência e na presença de 2-10 mM TMPyP apresenta a forma de um elipsóide prolato sem mudanças. Entretanto, o coeficiente de ionização, diminuiu com o aumento da concentração de porfirina, sugerindo a \"blindagem\" da carga aniônica do SDS pela porfirina catiônica. A supressão de fluorescência da TPPS4 e TMPyP foi estudada na ausência e na presença de diferentes micelas de surfactantes, tais como as de SDS, CTAC, HPS (N-hexadecil-N,N,dimetil-3-amônio-1-propano sulfato) e TX-100 (t-octil-fenoxi-polietoxi-etanol). O iodeto de potássio (KI) foi utilizado como supressor. Os gráficos de Stern-Volmer dos dados de fluorescência no estado estacionário foram ajustados pela equação quadrática, incluindo a supressão dinâmica (KD) e estática (KS). Os valores de KS são muito menores do que os valores de KD. Os resultados da TMPyP são consistentes com as constantes de ligação reportadas na literatura: uma redução significativa de supressão acontece para a TMPyP na presença de SDS, e uma redução moderada é observada para o sistema TMPyP-HPS e quase nenhuma mudança é vista para a TMPyP na presença de TX-100. Para o sistema CTAC-TPPS4 um aumento na supressão foi observado quando comparada com a TPPS4 em tampão puro. Isto provavelmente é associado ao acúmulo de iodeto na interface da micela catiônica. A atração entre a cabeça polar do CTAC e I-, e a repulsão entre SDS e I-, aumenta e reduz a supressão de fluorescência, respectivamente, das porfirinas que se localizam na interface micelar. A pequena supressão da TPPS4 em TX-100 é coerente com a forte ligação entre a TPPS4-TX-100 reportada na literatura. A TPPS4 e a TMPyP na presença de concentrações baixas dos surfactantes CTAC e SDS, respectivamente, apresentaram formação de agregados pré-micelares. A adição de surfactante neutro, TX-100, reduziu o efeito de agregação, acompanhada pelas várias técnicas espectroscópicas utilizadas neste trabalho. Portanto, sob condições onde temos a máxima formação de agregados (porfirina-surfactante), a titulação da TPPS4 com micelas de 40%CTAC-60%TX-100 e a TMPyP com micelas de 80%SDS-20%TX-100 não foi suficiente para eliminar a agregação, apesar da diminuição significativa do efeito de supressão de fluorescência e da intensidade de luz espalhada. A interação da TMPyP com 1-Palmitoil-2-Oleoil-sn-Glicero-3-fosfocolina (POPC), 1-Palmitoil-2-Oleoil-sn-Glicero-3-[Fosfo-rac-(1-glicero)] (POPG) e a mistura POPC + POPG é predominantemente devido à contribuição de eletrostática. O aumento da carga negativa, devido à adição de POPG, favorece a interação das vesículas com a porfirina catiônica. Na segunda parte deste trabalho foram estudados os efeitos de três surfactantes na estrutura oligomérica da hemoglobina extracelular gigante de Glossoscolex paulistus (HbGp) na sua forma oxi. O estudo com o SDS, CTAC e HPS permitiu diferenciar os efeitos de cargas opostas da cabeça polar dos surfactantes na dissociação da estrutura oligomérica e na autoxidação da hemoglobina. A interação do HPS com HbGp foi claramente menos intensa que a interação desta hemoglobina com os surfactantes catiônico (CTAC) e aniônico (SDS). Provavelmente, esta menor interação da HbGp com HPS, quando comparada com o SDS e o CTAC, é devido a menor atração eletrostática entre o HPS e os sítios iônicos da proteina. Dados espectroscópicos foram discutidos e comparados com os da literatura, afim de compreender a interação hemoglobina-surfactante, e como o ponto isoelétrico ácido (pI) pode influenciar na relação da estrutura-atividade das hemoglobinas gigantes extracelulares. As amostras de HbGp foram estudadas por espalhamento de luz dinâmico (DLS do inglês \"Dynamic light scattering\"). Na faixa de pH 6.0 a 8.0, HbGp é bastante estável e a distribuição de tamanho das partículas é monodispersa com um diâmetro hidrodinâmico médio (Dh) de 27 nm. O aumento dos valores de pH (pH>9.0) induziu um processo de dissociação irreversível, resultando num valor do Dh menor (10 nm). A diminuição do Dh sugere uma dissociação completa da hemoglobina. Em pH>9,0 a cinética de dissociação é lenta, com um mínimo 24 h para ser completada. As constantes cinéticas de dissociação aumentam progressivamente, com o aumento do valor do pH. As curvas de melting point para HbGp apresentaram dissociação oligomérica e desnaturação da proteina em função do pH. Os processos de autoxidação e dissociação estão intimamente relacionados, de modo que a dissociação da proteina oligomérica promove um aumento na velocidade de autoxidação e vice-versa. / In the first part of this work interactions of the cationic meso tetrakis (4-N-methilpyridil) porphyrin (TMPyP) and meso-tetrakis (4-sulfonatophenyl) porphyrin (TPPS4) in the free base forms with membrane model systems (ionic micelles, mixed micelles and phospholipids vesicles) in aqueous solutions, have been investigated by optical absorption, resonance light scattering (RLS), fluorescence and SAXS (Small Angle X-Ray Scattering). The best-fit SAXS curves were obtained assuming for cetyltrimethylammonium chloride (CTAC) micelle a prolate ellipsoidal shape in the absence and upon incorporation of 2-10 mM TPPS4. SAXS results show that the presence of TPPS4 impacts on micellar hydrophobic core, leading to a micellar reassembling into smaller micelles. SAXS data analysis demonstrated a prolate ellipsoidal shape for sodium dodecyl sulfate (SDS) micelles; no significant changes in shape and size were observed for SDS-TMPyP co-micelles. Moreover, the ionization coefficient, α, decreases with the increase of the porphyrin concentration, suggesting the \"screening\" of the anionic charge of SDS by the cationic porphyrin. These results are consistent with optical absorption, fluorescence and RLS spectroscopies data, allowing to conclude that neutral surfactants present a smaller interaction with the cationic porphyrin as compared with ionic surfactants. Fluorescence quenching of TPPS4 and TMPyP is studied in aqueous solution and upon addition of micelles of SDS, CTAC, N-hexadecyl-N,N-dimethyl-3-ammonio-1- propanesulfonate (HPS) and t-octylphenoxypolyethoxyethanol (Triton X-100). Potassium iodide (KI) was used as quencher. Steady-state Stern-Volmer plots were best fitted by a quadratic equation, including dynamic (KD) and static (KS) quenching. KS was significantly smaller than KD. For TMPyP quenching results are consistent with reported binding constants: a significant reduction of quenching takes place for SDS, a moderate reduction is observed for HPS and almost no change is seen for Triton X-100. For CTAC-TPPS4 system an enhancement of quenching was observed as compared to pure buffer. This is probably associated to accumulation of iodide at the cationic micellar interface. The attraction between CTAC headgroups and I-, and repulsion between SDS and I-, enhances and reduces the fluorescence quenching, respectively, of porphyrins located at the micellar interface. The small quenching of TPPS4 in Triton X-100 is consistent with strong binding as reported in the literature. Anionic TPPS4 and cationic TMPyP in the presence of low concentrations of the surfactants CTAC and SDS, respectively, showed formation of aggregates, monitored by optical absorption, fluorescence and resonance light scattering intensity (RLS). The addition of nonionic surfactant, Triton X-100, reduced the effect of aggregation monitored by the various techniques used in the present work. Therefore, under conditions for the maximum of aggregate formation (porphyrin-surfactant), apparently, the CTAC: TX-100 ratio equal to 40:60 and SDS:TX-100 ratio equal to 80:20 are not sufficient to eliminate aggregation, despite the significant decrease of the quenching effect of fluorescence and of the light scattering intensity. The interaction of TMPyP with 1-Palmitoyl-2-Oleoyl-sn- Glycero-3-Phosphocholine (POPC), 1-Palmitoyl-2-Oleoyl-sn-Glycero-3-[Phospho-rac-(1- glycerol)] (POPG) and the mixture POPC+POPG is predominantly due to the electrostatic contribution. The increase of the negative charge, due to addition of POPG, favors the interaction of vesicles with the cationic porphyrin. On the second part of this work the effects of three surfactants upon the oligomeric structure of the giant extracellular hemoglobin of Glossoscolex paulistus (HbGp) in the oxy - form was studied. The use of SDS, CTAC and HPS has allowed to differentiate the effects of opposite headgroup charges on the oligomeric structure dissociation and hemoglobin autoxidation. Furthermore, the interaction of HPS with HbGp was clearly less intense than the interaction of this hemoglobin with cationic (CTAC) and anionic (SDS) surfactants. Probably, this lower interaction with HPS is due to the lower electrostatic attraction between the HPS surfactant and the protein surface ionic sites when compared to the electrostatic interaction between HbGp and cationic and anionic surfactants. Spectroscopic data are discussed and compared with the literature in order to improve the understanding of hemoglobin-surfactant interaction as well as the acid isoelectric point (pI) influence of the giant extracellular hemoglobins on its structure-activity relationship. HbGp samples were studied by dynamic light scattering (DLS). In the pH from range 6.0 to 8.0, HbGp is stable and a monodisperse size distribution with a z-average hydrodynamic diameter (Dh) of 27±1 nm is observed. More alkaline pH (pH>9.0) induced an irreversible dissociation process, resulting in smaller Dh of 10±1 nm. Dh decrease suggests a complete hemoglobin dissociation. At pH 9.0 the dissociation kinetics is slow, taking a minimum of 24 h to be completed. Dissociation rate constants progressively increase at higher pH. Melting curves for HbGp showed oligomeric dissociation and protein denaturation as a function of pH. Autoxidation and dissociation processes are intimately related, so that oligomeric protein dissociation promotes the increase of autoxidation rate and vice-versa.
33

BIOGEOGRAPHY AND DIVERSIFICATION OF THE ANDEAN SEEDSNIPES (Thinocoridae): AN ANTARCTIC AVIAN LINEAGE ?

IBARGUCHI, GABRIELA 18 August 2011 (has links)
South America and the Andes harbour a rich biodiversity. High levels of in-situ speciation, survival of relict lineages into modern times, and mixing of biotas (Gondwanian and North American), have been demonstrated to contribute to the extant biodiversity. Here I examined the four species in the shorebird family Thinocoridae (seedsnipes) as a test case of complementary hypotheses about the origins of this diversity: 1) that some lineages arose from cold-adapted Antarctic ancestors (post-Gondwana), and 2) that the Andes have promoted diversification through vicariance and via the creation of novel alpine niches. First, I reviewed the tectonic and environmental history of the Andes, and the major biogeographic patterns in South America. Second, I reviewed Antarctic and Southern Hemisphere paleoenvironments, putative refugia, colonisation routes, molecular and biogeographic studies, and found strong evidence supporting the role of Antarctica as a source of global cold-hardy biodiversity. Third, I developed universal protocols to purify mitochondrial DNA (mtDNA). Using these methods, I uncovered nuclear pseudogenes, true mtDNA heteroplasmy, and possible hybridisation between seedsnipe lineages. Fourth, I investigated geographic patterns in seedsnipe morphology in four species. I also investigated the relationships of ecogeographic variables related to cold on morphology. I found strong and significant regional differences particularly in the smaller Thinocorus species, including an effect of the high Central Andes. Altitude, latitude, and wind (the effect of cold) have shaped seedsnipe morphology; Thinocoridae as a group generally support Bergmann’s and Allen’s rules. Fifth, based on phylogeographic and phylogenetic analyses of mtDNA and hemoglobin sequences, a putative southern origin for seedsnipes was supported, and an early origin in alpine habitats is suggested. Sixth, I compared data on Andean uplift and glaciation in South America, and found concordance between seedsnipe diversity, known areas of endemism in other taxa, and paleoenvironmental history. Finally, I briefly examined molecular evolution in hemoglobins and mtDNA and found preliminary evidence of adaptations to high altitude (hemoglobins) and to cold (mtDNA and hemoglobins). In summary, an Antarctic ancestor for seedsnipes, pre-adapted for life in the Andes, is supported. Antarctica may have contributed a great proportion of cold-hardy biodiversity to the South and globally. / Thesis (Ph.D, Biology) -- Queen's University, 2011-08-17 23:30:31.324
34

Folding and Assembly of Multimeric Proteins: Dimeric HIV-1 Protease and a Trimeric Coiled Coil Component of a Complex Hemoglobin Scaffold: A Dissertation

Fitzgerald, Amanda Ann 22 August 2007 (has links)
Knowledge of how a polypeptide folds from a space-filling random coil into a biologically-functional, three-dimensional structure has been the essence of the protein folding problem. Though mechanistic details of DNA transcription and RNA translation are well understood, a specific code by which the primary structure dictates the acquisition of secondary, tertiary, and quarternary structure remains unknown. However, the demonstrated reversibility of in vitroprotein folding allows for a thermodynamic analysis of the folding reaction. By probing both the equilibrium and kinetics of protein folding, a protein folding mechanism can be postulated. Over the past 40 years, folding mechanisms have been determined for many proteins; however, a generalized folding code is far from clear. Furthermore, most protein folding studies have focused on monomeric proteins even though a majority of biological processes function via the association of multiple subunits. Consequently, a complete understanding of the acquisition of quarternary protein structure is essential for applying the basic principles of protein folding to biology. The studies presented in this dissertation examined the folding and assembly of two very different multimeric proteins. Underlying both of these investigations is the need for a combined analysis of a repertoire of approaches to dissect the folding mechanism for multimeric proteins. Chapter II elucidates the detailed folding energy landscape of HIV-1 protease, a dimeric protein containing β-barrel subunits. The folding of this viral enzyme exhibited a sequential three-step pathway, involving the rate-limiting formation of a monomeric intermediate. The energetics determined from this analysis and their applications to HIV-1 function are discussed. In contrast, Chapter III illustrates the association of a coiled coil component of L. terrestriserythrocruorin. This extracellular hemoglobin consists of a complex scaffold of linker chains with a central ring of interdigitating coiled coils. Allostery is maintained by twelve dodecameric hemoglobin subunits that dock upon this scaffold. Modest association was observed for this coiled coil, and the implications of this fragment to linker assembly are addressed. These studies depict the complexity of multimeric folding reactions. Chapter II demonstrates that a detailed energy landscape of a dimeric protein can be determined by combining traditional equilibrium and kinetic approaches with information from a global analysis of kinetics and a monomer construct. Chapter III indicates that fragmentation of large complexes can show the contributions of separate domains to hierarchical organization. As a whole, this dissertation highlights the importance of pursuing mulitmeric protein folding studies and the implications of these folding mechanisms to biological function.
35

Variáveis hematológicas e perfil do ferro na abdominoplastia após a cirurgia bariátrica / Hematological variables and iron status in abdominoplasty after bariatric surgery

Pedroso, Juan Carlos Montano [UNIFESP] 25 May 2011 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-05-25 / Introdução: O tratamento da deformidade na parede abdominal resultante do emagrecimento após a cirurgia bariátrica é a abdominoplastia, a qual pode induzir anemia pós-operatória. Além disso, a cirurgia bariátrica promove uma tendência a deficiência de ferro. Baixas reservas de ferro comprometem a eritropoese. Não há estudo avaliando o grau de anemia e sua evolução após a abdominoplastia pós-bariátrica. Objetivo: Avaliar a anemia e sua evolução após a abdominoplastia pós-bariátrica. Métodos: Os valores de hemoglobina, reticulócitos, ferro, ferritina, e índice de saturação da transferrina foram mensurados na véspera da abdominoplastia e na primeira, quarta e oitava semana de pós-operatório. A hemoglobina também foi mensurada com 48h de pós-operatório. Vinte mulheres adultas foram operadas e tiveram seus dados comparados com 12 controles. Resultados: Os níveis de hemoglobina caíram, em média, de 12,98g/dL para 10,8g/dL com 48h. Houve um aumento significante da hemoglobina no sétimo dia com correção de um terço do déficit, sem aumentos significantes posteriores. Houve um aumento dos reticulócitos na primeira semana. O ferro sérico e índice de saturação de transferrina caíram na primeira semana e mantiveram-se baixos. Os níveis de ferritina apresentaram aumento não significante na primeira semana e posteriormente caíram. Nenhuma das pacientes foi transfundida. Conclusão: Os níveis de hemoglobina caíram após a abdominoplastia e demonstraram um aumento na primeira semana de pós-operatório, com correção de um terço do déficit de hemoglobina, porém, não recuperaram por completo na oitava semana. Ao término do seguimento, 45% das pacientes desenvolveram deficiência de ferro e apresentaram déficit de hemoglobina maior que as pacientes que mantiveram estoques de ferro normais / Background: The treatment of the abdominal wall deformity resulted from weight loss after bariatric surgery is a mixed type of abdominoplasty, which can induce post-operative anemia. In addition, bariatric surgery itself promotes a tendency to iron deficiency which could compromise erythropoiesis. To our knowledge, there is no study evaluating the degree of anemia and its recovery after post-bariatric abdominoplasty. Methods: The values of hemoglobin, reticulocytes, iron, ferritin and transferrin saturation index were measured the day prior to abdominoplasty and the first, fourth and eighth weeks after surgery. Hemoglobin was measured within 48h after surgery. Twenty adult women underwent surgery and had their data compared with 12 controls. Results: Hemoglobin levels dropped significantly from 12,98g/dL to 10,8g/dL within 48h. Hemoglobin increased significantly to 11,5g/dL by day seven, with correction of one third of the deficit, without significant increases thereafter. There was an increase in reticulocytes in the first week. Serum iron and transferrin saturation index fell in the first week and remained low. Ferritin levels showed no significant increase in the first week and subsequently fell. None of the patients received blood transfusion. Conclusion: Hemoglobin levels fell from 12,98 g/dL to 10,8 g/dL after abdominoplasty and showed an increase in the first week after surgery, with correction of one third of the deficit, but did not completely recover in the eighth week. At the end of the follow-up, 45% of the patients developed an iron deficiency and had a hemoglobin deficit higher than the patients that maintained normal iron stores. / TEDE / BV UNIFESP: Teses e dissertações
36

Effect of a patient blood management programme on preoperative anaemia, transfusion rate, and outcome after primary hip or knee arthroplasty: a quality improvement cycle

Kotze, A., Carter, L. A., Scally, Andy J. January 2012 (has links)
No / There are few data on the associations between anaemia, allogeneic blood transfusion (ABT), patient blood management, and outcome after arthroplasty in the UK. National agencies nevertheless instruct NHS Trusts to implement blood conservation measures including preoperative anaemia management. Internationally, blood management programmes show encouraging results. METHODS: We retrospectively audited 717 primary hip or knee arthroplasties in a UK general hospital and conducted regression analyses to identify outcome predictors. We used these data to modify previously published algorithms for UK practice and audited its introduction prospectively. The retrospective audit group served as a control. RESULTS: Preoperative haemoglobin (Hb) concentration predicted ABT (odds ratio 0.25 per 1 g dl(-1), P<0.001). It also predicted the length of stay (LOS, effect size -0.7 days per 1 g dl(-1), P=0.004) independently of ABT, including in non-anaemic patients. Patient blood management implementation was associated with lower ABT rates for hip (23-7%, P<0.001) and knee (7-0%, P=0.001) arthroplasty. LOS for total hip replacement and total knee replacement decreased from 6 (5-8) days to 5 (3-7) and 4 (3-6) days, respectively, after algorithm implementation (P<0.001). The all-cause re-admission rate within 90 days decreased from 13.5% (97/717) before to 8.2% (23/281) after algorithm implementation (P=0.02). CONCLUSIONS: We conclude that preoperative Hb predicts markers of arthroplasty outcome in UK practice. A systematic approach to optimize Hb mass before arthroplasty and limit Hb loss perioperatively was associated with improved outcome up to 90 days after discharge.
37

Birth weight, head circumference, and prenatal exposure to acrylamide from maternal diet: the European prospective mother-child study (NewGeneris)

Pedersen, M., von Stedingk, H., Botsivali, M., Agramunt, S., Alexander, J., Brunborg, G., Chatzi, L., Fleming, S., Fthenou, E., Granum, B., Gutzkow, K.B., Hardie, L.J., Knudsen, L.E., Kyrtopoulos, S.A., Mendez, M.A., Merlo, D.F., Nielsen, J.K., Rydberg, P., Segerback, D., Sunyer, J., Wright, J., Tornqvist, M., Kleinjans, J.C., Kogevinas, M., NewGeneris, Consortium January 2012 (has links)
No / Acrylamide is a common dietary exposure that crosses the human placenta. It is classified as a probable human carcinogen, and developmental toxicity has been observed in rodents. OBJECTIVES: We examined the associations between prenatal exposure to acrylamide and birth outcomes in a prospective European mother-child study. METHODS: Hemoglobin (Hb) adducts of acrylamide and its metabolite glycidamide were measured in cord blood (reflecting cumulated exposure in the last months of pregnancy) from 1,101 singleton pregnant women recruited in Denmark, England, Greece, Norway, and Spain during 2006-2010. Maternal diet was estimated through food-frequency questionnaires. RESULTS: Both acrylamide and glycidamide Hb adducts were associated with a statistically significant reduction in birth weight and head circumference. The estimated difference in birth weight for infants in the highest versus lowest quartile of acrylamide Hb adduct levels after adjusting for gestational age and country was -132 g (95% CI: -207, -56); the corresponding difference for head circumference was -0.33 cm (95% CI: -0.61, -0.06). Findings were similar in infants of nonsmokers, were consistent across countries, and remained after adjustment for factors associated with reduced birth weight. Maternal consumption of foods rich in acrylamide, such as fried potatoes, was associated with cord blood acrylamide adduct levels and with reduced birth weight. CONCLUSIONS: Dietary exposure to acrylamide was associated with reduced birth weight and head circumference. Consumption of specific foods during pregnancy was associated with higher acrylamide exposure in utero. If confirmed, these findings suggest that dietary intake of acrylamide should be reduced among pregnant women.

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