962 resultados para Blood cells count


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The dynamics, shape, deformation, and orientation of red blood cells in microcirculation affect the rheology, flow resistance and transport properties of whole blood. This leads to important correlations of cellular and continuum scales. Furthermore, the dynamics of RBCs subject to different flow conditions and vessel geometries is relevant for both fundamental research and biomedical applications (e.g drug delivery). In this thesis, the behaviour of RBCs is investigated for different flow conditions via computer simulations. We use a combination of two mesoscopic particle-based simulation techniques, dissipative particle dynamics and smoothed dissipative particle dynamics. We focus on the microcapillary scale of several μm. At this scale, blood cannot be considered at the continuum but has to be studied at the cellular level. The connection between cellular motion and overall blood rheology will be investigated. Red blood cells are modelled as viscoelastic objects interacting hydrodynamically with a viscous fluid environment. The properties of the membrane, such as resistance against bending or shearing, are set to correspond to experimental values. Furthermore, thermal fluctuations are considered via random forces. Analyses corresponding to light scattering measurements are performed in order to compare to experiments and suggest for which situations this method is suitable. Static light scattering by red blood cells characterises their shape and allows comparison to objects such as spheres or cylinders, whose scattering signals have analytical solutions, in contrast to those of red blood cells. Dynamic light scattering by red blood cells is studied concerning its suitability to detect and analyse motion, deformation and membrane fluctuations. Dynamic light scattering analysis is performed for both diffusing and flowing cells. We find that scattering signals depend on various cell properties, thus allowing to distinguish different cells. The scattering of diffusing cells allows to draw conclusions on their bending rigidity via the effective diffusion coefficient. The scattering of flowing cells allows to draw conclusions on the shear rate via the scattering amplitude correlation. In flow, a RBC shows different shapes and dynamic states, depending on conditions such as confinement, physiological/pathological state and cell age. Here, two essential flow conditions are studied: simple shear flow and tube flow. Simple shear flow as a basic flow condition is part of any more complex flow. The velocity profile is linear and shear stress is homogeneous. In simple shear flow, we find a sequence of different cell shapes by increasing the shear rate. With increasing shear rate, we find rolling cells with cup shapes, trilobe shapes and quadrulobe shapes. This agrees with recent experiments. Furthermore, the impact of the initial orientation on the dynamics is studied. To study crowding and collective effects, systems with higher haematocrit are set up. Tube flow is an idealised model for the flow through cylindric microvessels. Without cell, a parabolic flow profile prevails. A single red blood cell is placed into the tube and subject to a Poiseuille profile. In tube flow, we find different cell shapes and dynamics depending on confinement, shear rate and cell properties. For strong confinements and high shear rates, we find parachute-like shapes. Although not perfectly symmetric, they are adjusted to the flow profile and maintain a stationary shape and orientation. For weak confinements and low shear rates, we find tumbling slippers that rotate and moderately change their shape. For weak confinements and high shear rates, we find tank-treading slippers that oscillate in a limited range of inclination angles and strongly change their shape. For the lowest shear rates, we find cells performing a snaking motion. Due to cell properties and resultant deformations, all shapes differ from hitherto descriptions, such as steady tank-treading or symmetric parachutes. We introduce phase diagrams to identify flow regimes for the different shapes and dynamics. Changing cell properties, the regime borders in the phase diagrams change. In both flow types, both the viscosity contrast and the choice of stress-free shape are important. For in vitro experiments, the solvent viscosity has often been higher than the cytosol viscosity, leading to a different pattern of dynamics, such as steady tank-treading. The stress-free state of a RBC, which is the state at zero shear stress, is still controversial, and computer simulations enable direct comparisons of possible candidates in equivalent flow conditions.

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This is an abstract of a presented talk at the European Biotechnology Conference held in Latvia during 05–07 May 2016

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The objective of this study was to study leukocytes characteristics of Acipenseridae of southern Caspian Sea stained by cytochemical stains in order to classify these cells more accurately. The samples were taken from Sturgeon propagation centers and International Sturgeon Research Institute in the north part of Iran. 10 fish were selected randomly from each age group (fingerling, 1, 2, 3 to 11 years) and blood samples were taken from caudal vein using syringes with no anticoagulant. Blood smears were prepared immediately and fixed by methanol. The smears then stained using cytochemical staining according to the Sigma-Aldrich instructions. Neutrophils were positive for Sudan Black-B(SBB), Periodic acid-Schiff (PAS) and Peroxidase (PER) but negative for choloroacetate esterase (CAE). Eosinophi is stained positively for PER and SBB and weakly for PAS, acid phosphatase (ACP), CAE and a-naphthyl acetate esterase (a-NAE). Basophil was absent in the studied blood smears. Lymphocytes were positive for ACP but weak for PAS, CAE and a-NAE. Monocytes stained positively for B-glucoronidase (BG) in Acipenser persicus 5 and 11 years group, in Acipenser stellatus 1 and 2 years group, in Acipenser gueldenstaedtii 1 year group, in Acipenser nudiventris 9 year and in Huso huso 7 year group and stained weakly for a-NAE.

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Our purpose was to study the determinants of coronary and carotid subclinical atherosclerosis, aortic stiffness and their relation with inflammatory biomarkers in familial hypercholesterolemia (FH) subjects. Furthermore, we evaluated the agreement degree of imaging and inflammatory markers` severity used for coronary heart disease (CHD) prediction. Coronary calcium scores (CCS), carotid intima media thickness (IMT), carotid-femoral pulse wave velocity (PWV), C reactive protein (CRP) and white blood cells count (WBC) were determined in 89 FH patients (39 +/- 14 years, mean LDL-C=279 mg/dl) and in 31 normal subjects (NL). The following values were considered as imaging and biomarkers` severity: CCS > 75th% for age and sex, IMT > 900 mu m, PWV > 12 m/s, and CRP > 3 mg/l. Coronary artery calcification (CAC) prevalence and severity, IMT, PWV and WBC values were higher in FH than in NL (all parameters, p < 0.05). After multivariate analysis, the following variables were considered independent determinants of (1) IMT: systolic blood pressure, 10-year CHD risk by Framingham risk scores (FRS) and apolipoprotein B (r(2)=0.33); (2) PWV: age (r(2)=0.35); (3) CAC as a continuous variable: male gender and LDL-cholesterol year score (LYS) (r(2)=0.32); (4) presence of CAC as dichotomous variable: FRS (p=0.0027) and LYS (p=0.0228). With the exception of a moderate agreement degree between IMT and PWV severity (kappa=0.5) all other markers had only a slight agreement level (kappa < 0.1). In conclusion, clinical parameters poorly explained IMT, CAC and PWV variability in FH subjects. Furthermore, imaging markers and inflammatory biomarkers presented a poor agreement degree of their severity for CHD prediction. (C) 2007 Elsevier Ireland Ltd. All rights reserved.

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SUMMARY Introduction: We present a fatal case of disseminated cryptococcosis in a young man whose diagnosis of HIV infection was made at the time of admission to the emergency room. Case report: The patient was a twenty-three-year-old man, with a history of daily fever during one month associated with diarrhea, weight loss, headache, vomiting and generalized seizures. He also had a history of diabetes mellitus, alcoholism and drug addiction. Upon physical examination the patient was pale, disoriented and had periods of agitation. White blood cells count was 3,440/mm3 (5% lymphocytes), hemoglobin was 10g/dL, platelets were 83,000/ mm3. Creatinine was 0.7 mg/dL; urea 19 mg/dL; Na, K, and liver enzymes were within normal limits. Lactic dehydrogenase was 494 IU/L. Cerebrospinal fluid (CSF) analysis revealed 10 white blood cells/mm3 (58% neutrophils, 31% lymphocytes, 11% monocytes) and 2 red blood cells/mm3. India ink test revealed six Cryptococcus yeasts/mm3. CSF glucose was 122 mg/dL and protein was 36 mg/ dL. VDRL test was negative and anti-HIV test was positive. Intravenous hydration, insulin, phenytoin, fluconazole, pyrimethamine, sulfadiazine, folinic acid, and amphotericin B were started. The patient did not improve and became obtunded and hypotensive. He was intubated and put on mechanical respiration. He received vasoactive drugs and died less than 24 hours after admission. A postmortem examination was performed and revealed disseminated cryptococcosis, with severe involvement of the kidneys. Conclusion: Cryptococcosis, as a rule, is a systemic disease that affects mostly immunocompromised individuals, especially patients with AIDS. When diagnosed late in its course it has a very high mortality.

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Protozoan and helminthes are frequently associated with persistent digestive complaints, not only in returning travelers from the tropics, but also in industrialized countries. The symptoms are often more vague than those associated to bacterial or viral infections and diarrhea is not always a key feature of the clinical presentation. Three stool examinations and a full blood cells count looking for eosinophilia is the comer stone of the investigations looking for digestive parasites. This article reviews the epidemiology, clinical presentation, diagnostic and management of digestive protozoans and helminthes.

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Os efeitos da captura (perseguição, contenção em puçá e exposição aérea) no perfil sanguíneo do cortisol, glicose, cloreto, sódio, potássio, cálcio e na osmolaridade, hematócrito, hemoglobina, número de células vermelhas (CV) e volume corpuscular médio (VCM) foram investigados no pacu (Piaractus mesopotamicus). Um total de 132 peixes (49,7 ± 11,7 g) foi submetido à captura com 3 ou 5 minutos de exposição aérea. Nove peixes de cada tratamento foram amostrados 5, 15, 30, 60 minutos e 24 horas depois e outros nove peixes foram amostrados antes da captura e considerados controle. A captura resultou em aumento do cortisol e glicose no sangue 30 e 5 minutos depois da captura, respectivamente, independente do tempo de exposição aérea. Ambos os indicadores recuperaram os valores controle em 24 horas. Nos dois grupos de peixes, o cloreto plasmático diminuiu 60 minutos após captura e não recuperou os valores controle, enquanto o sódio sérico aumentou entre 15 e 30 minutos recuperando a condição controle em 24 horas. Não houve alteração significativa nos valores de potássio, cálcio, osmolaridade ou no hematócrito, hemoglobina, CV e VCM como consequência da captura. Os estressores sequenciais aplicados no pacu durante a captura ativaram o eixo cérebro-pituitária-interrenal (respostas do cortisol e glicose), mas a ativação do eixo cérebro-sistema simpático-células cromafins foi aparentemente moderada (respostas iônicas e hematológicas).

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The hematological responses in tuvira (Gymnotus aff. inaequilabiatus) after clove oil anesthesia at different concentrations were evaluated in this study. Fish (n = 25) with average length of 26.8 +/- 2.4 cm and weighing 94.4 +/- 23.6 g were separated in five groups composed with five animals each and submitted individually to respective concentrations of clove oil: 40, 80, 120, 160 and 200 mg L-1. After anesthetic recuperation, the blood samples collection were performed, as well as complete hemogram. The results were submitted to analysis of variance, Tukey test (P<0.05) and Sperman's correlation analysis. There was an increase (P<0.05) on hematocrit, red blood cells count, thrombocytes count and in the values of neutrophils with increasing of clove oil concentrations. In addition, positive correlation (P<0.05) were observed on total leukocytes, as well as negative linear correlation (P<0.05) for mean corpuscular hemoglobin concentration (MCHC). The clove oil anesthesia on tuvira cause hematological changes with an effect dose-dependent. These changes should be considered mainly in future studies designed to establish the reference values of hematologic variables for this specie.

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Trinta gatas, saudáveis, foram submetidas à ovariectomia pela técnica convencional e por videolaparoscopia. Amostras de sangue foram obtidas com o objetivo de verificar a intensidade da resposta inflamatória por meio da análise das concentrações de proteinas de fase aguda e contagem de leucócitos antes e até 144 horas após procedimento cirúrgico. As proteínas que apresentaram aumento significativo 24 horas após a cirurgia foram: ceruloplasmina, hemopexina, haptoglobina e α1-glicoproteína ácida, 69,8%, 103,5%, 117,3% e 199,0%, respectivamente, para ovariectomia convencional, e 22,3%, 46,1%, 79,8% e 74,6%, respectivamente, para ovariectomia por videolaparoscopia. A resposta inflamatória foi mais evidente nas gatas submetidas à ovariectomia convencional. Os resultados mostram aumento e diminuição na concentração de proteínas de fase aguda e na contagem de leucócitos, podendo ser utilizados na avaliação da resposta inflamatória induzida por procedimentos cirúrgicos.

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The Pelger-Huët anomaly is a dominant autosomal disease, characterized by the incomplete segmentation of the granulocytes nucleus without lost of the cellular function. The heterozygotes form of this anomaly is assintomatic and it did not possess physic meant, while the homozygote form is rare and can be lethal, being therefore, important differentiates of other infectious alterations. The pseudo-anomaly can occasionally be observed in cases of granulocitic leukemia, mieloproliferatives Diseases, some infections and after exposition the determined drugs. We evaluate eleven members of a familiar nucleus and, after the blood cells analysis, six of then had presented neutrophils and eosinophils with nuclei characteristic of the heterozygotes form of the Pelger-Huët anomaly. The recognition of this leukocyte anomaly, mainly in patients without infection and presenting great number of not segmented neutrophils, can prevent wrong interpretations of the blood cells count and unnecessary clinical and therapeutically behaviors.

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As características hematológicas do jundiá Rhamdia quelen Quoy & Gaimard, 1824 (Osteichthyes: Pimelodidae), oriundo de cativeiro foram estudadas. Determinou-se o valor médio da contagem de eritrócitos, taxa de hemoglobina, hematócrito, volume corpuscular médio (VCM), concentração de hemoglobina corpuscular média (CHCM) e distribuição percentual de células sangüíneas de defesa orgânica. As células sangüíneas de defesa orgânica (leucócitos e trombócitos) foram identificadas e caracterizadas morfologicamente. Trombócitos e linfócitos foram as células sangüíneas de defesa orgânica mais freqüente nas extensões sangüíneas do R. quelen. A análise de regressão mostrou correlação linear negativa entre o percentual de trombócitos e linfócitos. Os resultados deste estudo fornecem valores sangüíneos normais em R. quelen, em cultivo intensivo, que poderão servir de comparação com dados dessa espécie em outras situações de cultivo.

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Estudaram-se as variáveis eritrométricas, leucométricas e a concentração de proteína total (PT) de éguas gestantes das raças Brasileiro de Hipismo (BH) e Bretão. Utilizaram-se 175 éguas sadias, com 3 a 13 anos de idade. Dentre as éguas utilizadas, 89 foram da raça BH, divididas em 14 não-prenhes e 75 prenhes, e 86 éguas da raça Bretão divididas em 11 não-prenhes e 75 prenhes. As éguas foram subdivididas em quatro grupos por raça: grupo controle (éguas não-prenhes, n=14 para BH e n=11 para Bretão); grupo I (primeiro período de gestação, 25-110 dias, n=25 para BH e Bretão), grupo II (segundo período de gestação, 111-210 dias, n=25 para BH e Bretão); e grupo III (terceiro período de gestação, 211-340 dias, n=25 para BH e Bretão). Os valores médios de cada variável eritrométrica, leucométrica e de proteína total foram obtidos para cada raça e, posteriormente, realizou-se comparação entre as mesmas. O número de hemácias (He), volume globular (VG) e teor de hemoglobina (Hb) aumentaram no segundo período de gestação e diminuíram no último período tanto para a raça BH, como para a raça Bretão. Além disso, essas mesmas variáveis apresentaram diferença estatística significativa tanto nas éguas não-prenhas como nas prenhes durante os três períodos gestacionais. Os valores médios obtidos de leucócitos e neutrófilos segmentados aumentaram a partir do segundo período de gestação para as duas raças estudadas.