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1.
Opt Express ; 30(2): 1723-1736, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209327

RESUMO

We present an automated method for COVID-19 screening based on reconstructed phase profiles of red blood cells (RBCs) and a highly comparative time-series analysis (HCTSA). Video digital holographic data -was obtained using a compact, field-portable shearing microscope to capture the temporal fluctuations and spatio-temporal dynamics of live RBCs. After numerical reconstruction of the digital holographic data, the optical volume is calculated at each timeframe of the reconstructed data to produce a time-series signal for each cell in our dataset. Over 6000 features are extracted on the time-varying optical volume sequences using the HCTSA to quantify the spatio-temporal behavior of the RBCs, then a linear support vector machine is used for classification of individual RBCs. Human subjects are then classified for COVID-19 based on the consensus of their cells' classifications. The proposed method is tested on a dataset of 1472 RBCs from 24 human subjects (10 COVID-19 positive, 14 healthy) collected at UConn Health Center. Following a cross-validation procedure, our system achieves 82.13% accuracy, with 92.72% sensitivity, and 73.21% specificity (area under the receiver operating characteristic curve: 0.8357). Furthermore, the proposed system resulted in 21 out of 24 human subjects correctly labeled. To the best of our knowledge this is the first report of a highly comparative time-series analysis using digital holographic microscopy data.


Assuntos
COVID-19/diagnóstico por imagem , Eritrócitos/classificação , Holografia/métodos , Microscopia Intravital/métodos , COVID-19/sangue , Estudos de Casos e Controles , Desenho de Equipamento , Holografia/instrumentação , Humanos , Microscopia Intravital/instrumentação , Dados Preliminares , Curva ROC , Sensibilidade e Especificidade
2.
Medicine (Baltimore) ; 100(37): e27255, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34664873

RESUMO

ABSTRACT: This study was performed to determine whether red blood cell distribution width (RDW) is associated with 3-month poor functional outcome in patients undergoing thrombolytic therapy for acute ischemic stroke.RDW was measured in patients with thrombolytic therapy in emergency department. Functional outcome was assessed after 3 months and poor functional outcome was defined as modified Rankin scale 3 to 6.A total of 240 patients were enrolled, and 82 (34.2%) had a poor functional outcome. The median RDW was significantly elevated in patients with a poor functional outcome compare with those with a good outcome. RDW was independently associated with a 3-month poor functional outcome (odds ratio 3.369, 95% confidence interval 2.214-5.125). The optimal RDW cutoff for predicting 3-month poor functional outcome was 12.8%, and the area under the curve for RDW was 0.818 (95% confidence interval 0.761-0.876). The area under the curve for RDW was higher in male patients than in female patients. The RDW correlated positively with the modified Rankin scale score after 3 months and the initial National Institutes of Health Stroke Scale score.Initial higher RDW level is related to a 3-month poor functional outcome in patients undergoing thrombolytic therapy for acute ischemic stroke.


Assuntos
Eritrócitos/classificação , AVC Isquêmico/complicações , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Terapia Trombolítica/normas , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Feminino , Humanos , AVC Isquêmico/epidemiologia , AVC Isquêmico/mortalidade , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Avaliação de Resultados em Cuidados de Saúde/métodos , Prognóstico , Curva ROC , Estudos Retrospectivos , Seul/epidemiologia , Estatísticas não Paramétricas , Terapia Trombolítica/métodos , Terapia Trombolítica/estatística & dados numéricos , Pesos e Medidas/instrumentação
3.
Sci Rep ; 11(1): 13553, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193899

RESUMO

Combining microfluidics technology with machine learning represents an innovative approach to conduct massive quantitative cell behavior study and implement smart decision-making systems in support of clinical diagnostics. The spleen plays a key-role in rare hereditary hemolytic anemia (RHHA), being the organ responsible for the premature removal of defective red blood cells (RBCs). The goal is to adapt the physiological spleen filtering strategy for in vitro study and monitoring of blood diseases through RBCs shape analysis. Then, a microfluidic device mimicking the slits of the spleen red pulp area and video data analysis are combined for the characterization of RBCs in RHHA. This microfluidic unit is designed to evaluate RBC deformability by maintaining them fixed in planar orientation, allowing the visual inspection of RBC's capacity to restore their original shape after crossing microconstrictions. Then, two cooperative learning approaches are used for the analysis: the majority voting scheme, in which the most voted label for all the cell images is the class assigned to the entire video; and the maximum sum of scores to decide the maximally scored class to assign. The proposed platform shows the capability to discriminate healthy controls and patients with an average efficiency of 91%, but also to distinguish between RHHA subtypes, with an efficiency of 82%.


Assuntos
Anemia Hemolítica Congênita , Eritrócitos , Processamento de Imagem Assistida por Computador , Dispositivos Lab-On-A-Chip , Aprendizado de Máquina , Técnicas Analíticas Microfluídicas , Anemia Hemolítica Congênita/classificação , Anemia Hemolítica Congênita/patologia , Deformação Eritrocítica , Eritrócitos/classificação , Eritrócitos/patologia , Feminino , Humanos , Masculino
4.
Opt Express ; 28(22): 33504-33515, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33115011

RESUMO

Rapid cell identification is achieved in a compact and field-portable system employing single random phase encoding to record opto-biological signatures of living biological cells of interest. The lensless, 3D-printed system uses a diffuser to encode the complex amplitude of the sample, then the encoded signal is recorded by a CMOS image sensor for classification. Removal of lenses in this 3D sensing system removes restrictions on the field of view, numerical aperture, and depth of field normally imposed by objective lenses in comparable microscopy systems to enable robust 3D capture of biological volumes. Opto-biological signatures for two classes of animal red blood cells, situated in a microfluidic device, are captured then input into a convolutional neural network for classification, wherein the AlexNet architecture, pretrained on the ImageNet database is used as the deep learning model. Video data was recorded of the opto-biological signatures for multiple samples, then each frame was treated as an input image to the network. The pre-trained network was fine-tuned and evaluated using a dataset of over 36,000 images. The results show improved performance in comparison to a previously studied Random Forest classification model using extracted statistical features from the opto-biological signatures. The system is further compared to and outperforms a similar shearing-based 3D digital holographic microscopy system for cell classification. In addition to improvements in classification performance, the use of convolutional neural networks in this work is further demonstrated to provide improved performance in the presence of noise. Red blood cell identification as presented here, may serve as a key step toward lensless pseudorandom phase encoding applications in rapid disease screening. To the best of our knowledge this is the first report of lensless cell identification in single random phase encoding using convolutional neural networks.


Assuntos
Eritrócitos/classificação , Holografia/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Redes Neurais de Computação , Imagem Óptica/instrumentação , Animais , Bovinos , Cavalos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional/instrumentação , Aprendizado de Máquina
5.
Transfusion ; 60(11): 2633-2646, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32812244

RESUMO

BACKGROUND: Characteristics of red blood cells (RBCs) are influenced by donor variability. This study assessed quality and metabolomic variables of RBC subpopulations of varied biologic age in red blood cell concentrates (RCCs) from male and female donors to evaluate their contribution to the storage lesion. STUDY DESIGN AND METHODS: Red blood cell concentrates from healthy male (n = 6) and female (n = 4) donors were Percoll separated into less dense ("young", Y-RCCs) and dense ("old", O-RCCs) subpopulations, which were assessed weekly for 28 days for changes in hemolysis, mean cell volume (MCV), hemoglobin concentration (MCHC), hemoglobin autofluorescence (HGB), morphology index (MI), oxygen affinity (p50), rigidity, intracellular reactive oxygen species (ROS), calcium ([Ca2+ ]), and mass spectrometry-based metabolomics. RESULTS: Young RCCs having disc-to-discoid morphology showed higher MCV and MI, but lower MCHC, HGB, and rigidity than O-RCCs, having discoid-to-spheroid shape. By Day 14, Y-RCCs retained lower hemolysis and rigidity and higher p50 compared to O-RCCs. Donor sex analyses indicated that females had higher MCV, HGB, ROS, and [Ca2+ ] and lower hemolysis than male RBCs, in addition to having a decreased rate of change in hemolysis by Day 28. Metabolic profiling indicated a significant sex-related signature across all groups with increased markers of high membrane lipid remodeling and antioxidant capacity in Y-RCCs, whereas O-RCCs had increased markers of oxidative stress and decreased coping capability. CONCLUSION: The structural, functional, and metabolic dissimilarities of Y-RCCs and O-RCCs from female and male donors demonstrate RCC heterogeneity, where RBCs from females contribute less to the storage lesion and age slower than males.


Assuntos
Doadores de Sangue , Preservação de Sangue , Senescência Celular , Eritrócitos , Estresse Oxidativo , Adulto , Eritrócitos/classificação , Eritrócitos/citologia , Eritrócitos/metabolismo , Feminino , Humanos , Masculino
6.
Hemoglobin ; 44(1): 31-36, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32400249

RESUMO

The best approach for prevention of alloimmunization in ß-thalassemia (ß-thal) patients is perfect matching of all red blood cell (RBC) antigens associated with clinically significant antibodies, but this is expensive and may limit the blood supply. Knowing the most common alloantibodies in transfusion-dependent ß-thal patients make it possible to establish more cost-effective matching strategies for high-risk antigens. With this in mind, we intended to determine the most common alloantibodies in different parts of Iran. A total of 480 alloimmunized ß-thal major (ß-TM) patients who were referred to the Tehran Adult Thalassemia Clinic in Tehran, Iran from all provinces between 2015 and 2017, were included in this study. Antibody screening was performed on the fresh serum of all patients. Subsequently, the specification of antibodies was identified using a panel of recognized blood group antigens. Anti-K was the most common alloantibody detected in ß-TM patients in all regions of Iran. The prevalence of this antibody reached to 37.7% in the western area, but in southeastern region, anti-E was predominant. Interestingly, the rare alloantibody anti-Kpa was detected with a high prevalence in the western region. The antibodies against E and D antigens were also encountered with high prevalence in most regions of the country. The present study demonstrated the distribution of alloantibodies in alloimmunized transfusion-dependent ß-thal patients from diverse ethnic and racial backgrounds of the Iranian population. The results of this study can be used as a basis to establish cost-effective RBC phenotyping and matching strategies for high-risk antigens in donors and chronic transfusion recipients in different regions of Iran.


Assuntos
Transfusão de Sangue/métodos , Eritrócitos/imunologia , Hemoglobinas Anormais/genética , Isoanticorpos/sangue , Globinas beta/genética , Talassemia beta/imunologia , Adolescente , Adulto , Idoso , Autoimunidade , Antígenos de Grupos Sanguíneos/imunologia , Tipagem e Reações Cruzadas Sanguíneas , Criança , Pré-Escolar , Eritrócitos/classificação , Etnicidade , Feminino , Expressão Gênica , Hemoglobinas Anormais/imunologia , Humanos , Soros Imunes/química , Lactente , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Globinas beta/deficiência , Globinas beta/imunologia , Talassemia beta/epidemiologia , Talassemia beta/etnologia , Talassemia beta/terapia
7.
Interdiscip Sci ; 12(2): 217-225, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32394271

RESUMO

Malaria is one of the epidemics that can cause human death. Accurate and rapid diagnosis of malaria is important for treatment. Due to the limited number of data and human factors, the prediction performance and reliability of traditional classification methods are often affected. In this study, we propose an efficient and novel classification network named Attentive Dense Circular Net (ADCN) which based on Convolutional Neural Networks (CNN). The ADCN is inspired by the ideas of residual and dense networks and combines with the attention mechanism. We train and evaluate our proposed model on a publicly available red blood cells (RBC) dataset and compare ADCN with several well-established CNN models. Compared to other best performing CNN model in our experiments, ADCN shows superiority in all performance criteria such as accuracy (97.47% vs 94.61%), sensitivity (97.86% vs 95.20%) and specificity (97.07% vs 92.87%). Finally, we discuss the obtained results and analyze the difficulties of RBCs classification.


Assuntos
Eritrócitos/parasitologia , Malária/diagnóstico , Modelos Biológicos , Redes Neurais de Computação , Plasmodium/crescimento & desenvolvimento , Aprendizado Profundo , Eritrócitos/classificação , Humanos , Malária/sangue , Malária/parasitologia , Reprodutibilidade dos Testes
8.
Appl Opt ; 59(10): 2969-2975, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32400572

RESUMO

In this work, the development and application of a cost-effective and robust digital lensless holographic microscopy (DLHM) system is presented. In the simple architecture of DLHM based on a point source and a digital camera, the production of the former is introduced by means of an engineered step-index optical fiber with a cone-shaped end tip. The conventional and regularly expensive point source in DLHM is produced by means of a high-numerical-aperture microscope objective and a metallic wavelength-sized pinhole. The proposed replacement renders to DLHM additional simplicity of building, in addition to mechanical stability and robustness, and further reduces the cost of the microscope. The simplified cost-effective DLHM architecture is utilized for imaging resolution test targets and samples of human blood and pond water, revealing competitive mechanical stability and trustable phase images of the imaged specimens.


Assuntos
Eritrócitos/classificação , Holografia/instrumentação , Microscopia/instrumentação , Fibras Ópticas , Água/química , Sangue , Análise Custo-Benefício , Desenho de Equipamento , Holografia/economia , Humanos , Processamento de Imagem Assistida por Computador , Microscopia/economia
9.
Malar J ; 19(1): 21, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941490

RESUMO

BACKGROUND: Multiple red blood cell (RBC) variants appear to offer protection against the most severe forms of Plasmodium falciparum malaria. Associations between these variants and uncomplicated malaria are less clear. METHODS: Data from a longitudinal cohort study conducted in 3 sub-counties in Uganda was used to quantify associations between three red blood cell variants Hb [AA, AS, S (rs334)], alpha thalassaemia 3.7 kb deletion, and glucose-6-phosphate dehydrogenase deficiency A-(G6PD 202A genotype) and malaria incidence, parasite prevalence, parasite density (a measure of anti-parasite immunity) and body temperature adjusted for parasite density (a measure of anti-disease immunity). All analyses were adjusted for age, average household entomological inoculation rate, and study site. Results for all variants were compared to those for wild type genotypes. RESULTS: In children, HbAS was associated, compared to wild type, with a lower incidence of malaria (IRR = 0.78, 95% CI 0.66-0.92, p = 0.003), lower parasite density upon infection (PR = 0.66, 95% CI 0.51-0.85, p = 0.001), and lower body temperature for any given parasite density (- 0.13 â„ƒ, 95% CI - 0.21, - 0.05, p = 0.002). In children, HbSS was associated with a lower incidence of malaria (IRR = 0.17, 95% CI 0.04-0.71, p = 0.02) and lower parasite density upon infection (PR = 0.31, 95% CI 0.18-0.54, p < 0.001). α-/αα thalassaemia, was associated with higher parasite prevalence in both children and adults (RR = 1.23, 95% CI 1.06-1.43, p = 0.008 and RR = 1.52, 95% CI 1.04-2.23, p = 0.03, respectively). G6PD deficiency was associated with lower body temperature for any given parasite density only among male hemizygote children (- 0.19 â„ƒ, 95% CI - 0.31, - 0.06, p = 0.003). CONCLUSION: RBC variants were associated with non-severe malaria outcomes. Elucidation of the mechanisms by which they confer protection will improve understanding of genetic protection against malaria.


Assuntos
Eritrócitos/citologia , Malária/sangue , Adulto , Fatores Etários , Distribuição Binomial , Cuidadores , Criança , Pré-Escolar , Estudos de Coortes , Eritrócitos/química , Eritrócitos/classificação , Feminino , Humanos , Incidência , Lactente , Estudos Longitudinais , Malária/epidemiologia , Malária/genética , Malária/parasitologia , Masculino , Parasitemia/sangue , Parasitemia/epidemiologia , Parasitemia/genética , Parasitemia/parasitologia , Prevalência , Estudos Prospectivos , Fatores Sexuais , Uganda/epidemiologia , Adulto Jovem
10.
Medicine (Baltimore) ; 98(11): e14884, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30882699

RESUMO

BACKGROUND: Restrictive red blood cell transfusion strategy is implemented to minimize risk following allogeneic blood transfusion in adult cardiac surgery. However, it is still unclear if it can be applied to pediatric cardiac patients. The purpose of this systematic review and meta-analysis was to determine the effect of postoperative restrictive transfusion thresholds on clinical outcomes based on up-to-date results of randomized controlled trials (RCTs) and observational studies in pediatric cardiac surgery. METHOD: We searched for RCTs and observational studies in the following databases: the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and ClinicalTrials.gov from their inception to October 26, 2017. We also searched reference lists of published guidelines, reviews, and relevant articles, as well as conference proceedings. No language restrictions were applied and no observational study met the inclusion criteria. RESULTS: Four RCTs on cardiac surgery involving 454 patients were included. There were no differences in the pooled fixed effects of intensive care unit (ICU) stay between the liberal and restrictive transfusion thresholds (standardized mean difference SMD, 0.007; 95% confidence interval CI, -0.18-0.19; P = .94). There were also no differences in the length of hospital stay (SMD, -0.062; 95% CI, -0.28-0.15; P = .57), ventilation duration (SMD, -0.015; 95% CI, -0.25-0.22; P = .90), mean arterial lactate level (SMD, 0.071; 95% CI, -0.22-0.36; P = .63), and mortality (risk ratio, 0.49; 95% CI, 0.13-1.94; P = .31). There was no inter-trial heterogeneity for any pooled analysis. Publication bias was tested using Egger, Begg, or the trim-and-fill test, and the results indicated no significant publication bias. CONCLUSION: Evidence from RCTs in pediatric cardiac surgery, though limited, showed non-inferiority of restrictive thresholds over liberal thresholds in length of ICU stay and other outcomes following red blood cell transfusion. Further high-quality RCTs are necessary to confirm the findings.


Assuntos
Transfusão de Sangue/classificação , Procedimentos Cirúrgicos Cardíacos/métodos , Eritrócitos/classificação , Resultado do Tratamento , Transfusão de Sangue/métodos , Humanos , Pediatria/métodos
11.
Arq. bras. med. vet. zootec. (Online) ; 71(1): 93-101, jan.-fev. 2019. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-989370

RESUMO

The objective of this study was to perform a quality control assessment of red blood cells after standardization of the blood production stages. For this purpose, separation of the blood components to obtain red blood cells, the storage of the blood packets and an evaluation of blood quality were performed. The mean (± SD) volume, globular volume, hemoglobin and hemolysis percentage of the red blood cell concentrate were 299.77±30.08mL, 60.87±2.60%, 20.57±0.93g/DL and 0.09±0.07%, respectively. The means (± SD) of the volume, globular volume, total hemoglobin percentage of hemolysis and hemoglobin per unit of packed red blood cells after the storage period (8.83±6.73 days) were 57.55±3.01%, 20.30±0.89 0, 20±0.12%, and 60.90±7.65. The red blood cell packets were within the parameters of quality control established by Health Ministry legislation in humans and allow us to conclude that the standardization of blood production stages involves the selection of donors until the end of storage and is necessary to produce quality red blood cells. Quality control aims to find possible flaws in the procedures to be repaired, increasing transfusion safety.(AU)


O objetivo deste estudo foi realizar o controle de qualidade do concentrado de hemácias após a padronização das etapas de produção do sangue. Para isso, realizou-se separação de hemocomponentes para obtenção de concentrado de hemácias, armazenamento das bolsas de sangue e avaliação da qualidade delas. Os valores médios (± DP) do volume, do volume globular, da hemoglobina e do percentual de hemólise do concentrado de hemácias foram: 299,77±30,08mL, 60,87±2,60%, 20,57±0,93g/DL e 0,09±0,07%, respectivamente. Os valores médios (± DP) do volume globular, da hemoglobina total percentual de hemólise e da hemoglobina por unidade de concentrado de hemácias após o período de armazenamento (8,83±6,73 dias) foram: 57,55±3,01%, 20,30±0,89 0,20±0,12%, 60,90±7,65. As bolsas de concentrado de hemácias ficaram dentro dos parâmetros de controle de qualidade estabelecidos pela legislação do Ministério da Saúde em humanos e possibilitaram concluir que a padronização das etapas de produção do sangue envolve desde a seleção de doadores até o final do armazenamento e é necessária para produzir concentrado de hemácias com qualidade. O controle de qualidade visa encontrar possíveis falhas nos procedimentos para que estas possam ser reparadas, aumentando, assim, a segurança transfusional.(AU)


Assuntos
Animais , Cães , Cães/sangue , Eritrócitos/classificação , Medicina Transfusional/classificação
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 4068-4071, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946765

RESUMO

Specialists may gauge the severity of sickle cell disease crisis by quantifying the number of abnormal-looking and sickle-shaped erythrocytes in blood smears. State-of-the-art integral geometry-based descriptors for automatic classification of erythrocytes as normal cells, sickle cells or cells with other deformations have achieved excellent results. Unfortunately, they are computationally expensive, requiring powerful desktop computers and a great deal of memory to run. We propose two new integral geometry-based descriptors for the shape of erythrocytes. Like state-of-the-art techniques, the overall sensitivity of our solutions is above 94%. Nevertheless, our descriptors are designed to avoid a great amount of computation in comparison to similar solutions and to present a lower memory footprint. Our descriptors offer a high specificity of normal cells and a high sensitivity of deformed cells, making them a good alternative in clinical applications.


Assuntos
Anemia Falciforme/diagnóstico , Biologia Computacional , Eritrócitos/citologia , Reconhecimento Automatizado de Padrão , Eritrócitos/classificação , Humanos , Sensibilidade e Especificidade
13.
Braz. J. Pharm. Sci. (Online) ; 55: e17680, 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1039046

RESUMO

Resealed erythrocytes have been explored in various dimensions of drug delivery, owing to their high biocompatibility and inability to initiate immune response. The present research was designed to evaluate the drug delivery potential of erythrocytes by loading a hydrophobic anti-malarial drug, Artemether. Three different loading techniques were applied to achieve maximum optimized drug loading. A HPLC method was validated for drug quantification in erythrocytes. The relatively high loading was achieved using hypotonic treatment was 31.39% as compared to other two methods. These, drug loaded erythrocytes were characterized for membrane integrity via ESR showing higher ESR values for drug loaded cells as compared to normal cells. Moreover, microscopic evaluation was done to observe morphological changes in erythrocytes after successful loading which showed swollen cells with slight rough surface as compared to smooth surface of normal cells. Drug release was studied for 8 h which showed more than 80% release within 3-7 h from erythrocytes treated with different hypotonic methods. Overall, the study revealed a potential application of erythrocytes in delivery of hydrophobic drugs using hypotonic treatment as compared to other methods.


Assuntos
Eritrócitos/classificação , Liberação Controlada de Fármacos , Artemeter/administração & dosagem , Preparações Farmacêuticas/administração & dosagem , Cromatografia Líquida de Alta Pressão/métodos
14.
PLoS Comput Biol ; 14(6): e1006278, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29906283

RESUMO

The manual evaluation, classification and counting of biological objects demands for an enormous expenditure of time and subjective human input may be a source of error. Investigating the shape of red blood cells (RBCs) in microcapillary Poiseuille flow, we overcome this drawback by introducing a convolutional neural regression network for an automatic, outlier tolerant shape classification. From our experiments we expect two stable geometries: the so-called 'slipper' and 'croissant' shapes depending on the prevailing flow conditions and the cell-intrinsic parameters. Whereas croissants mostly occur at low shear rates, slippers evolve at higher flow velocities. With our method, we are able to find the transition point between both 'phases' of stable shapes which is of high interest to ensuing theoretical studies and numerical simulations. Using statistically based thresholds, from our data, we obtain so-called phase diagrams which are compared to manual evaluations. Prospectively, our concept allows us to perform objective analyses of measurements for a variety of flow conditions and to receive comparable results. Moreover, the proposed procedure enables unbiased studies on the influence of drugs on flow properties of single RBCs and the resulting macroscopic change of the flow behavior of whole blood.


Assuntos
Biologia Computacional/métodos , Eritrócitos/classificação , Eritrócitos/citologia , Velocidade do Fluxo Sanguíneo , Forma Celular/fisiologia , Eritrócitos/fisiologia , Humanos , Hidrodinâmica , Aprendizado de Máquina , Modelos Teóricos , Redes Neurais de Computação
15.
Sociol Health Illn ; 40(4): 687-701, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29498085

RESUMO

The case of cultured red blood cells (RBCs) currently being grown in a laboratory for future use in human transfusion raises questions about the ontological status of such products of modern biotechnology. This paper presents results from a six-year ethnographic study involving interviews, focus groups and other forms of engagement with the scientific research team and other stakeholders, including public groups, which sought to understand respondents' reactions to cultured RBCs. These cells, derived from stem cell technology, have the potential to address the global shortage of donated blood. How these blood cells are situated within the spectrum of 'natural' to 'synthetic' will shape expectations and acceptance of this product, both within the scientific community and by wider publics: these blood cells are both novel and yet, at the same time, very familiar. Drawing on discussions related to classification and 'anchoring', we examine the contrasting discourses offered by our respondents on whether these blood cells are 'natural' or not and consider the impact that naming might have on both their future regulation and the eventual uptake of cultured RBCs by society.


Assuntos
Transfusão de Sangue , Eritrócitos/classificação , Pesquisa com Células-Tronco/ética , Antropologia Cultural , Doadores de Sangue , Transfusão de Sangue/métodos , Células Cultivadas , Grupos Focais , Humanos , Entrevistas como Assunto , Opinião Pública
16.
Eur J Nutr ; 57(5): 1771-1780, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28447203

RESUMO

PURPOSE: Folate required to achieve desirable red blood cell (RBC) folate concentrations within 4-8 weeks pre-pregnancy is not known. We studied the effect of supplementation with 400 or 800 µg/day folate in achieving RBC-folate ≥906 nmol/L. METHODS: Non-pregnant women were randomized to receive multinutrient supplements containing 400 µg/day (n = 100) or 800 µg/day (n = 101) folate [folic acid and (6S)-5-CH3-H4folate-Ca (1:1)]. The changes of folate biomarkers were studied after 4 and 8 weeks in the 198 women who returned at least for visit 2. RESULTS: At baseline, 12 of the 198 participants (6.1%) had RBC-folate <340 nmol/L, but 88% had levels <906 nmol/L. The RBC-folate concentrations increased significantly in the 800 µg/day (mean ± SD = 652 ± 295 at baseline; 928 ± 330 at 4 weeks; and 1218 ± 435 nmol/L at 8 weeks) compared with the 400 µg/day [632 ± 285 at baseline (p = 0.578); 805 ± 363 at 4 weeks (p < 0.001); 1021 ± 414 nmol/L at 8 weeks (p < 0.001)]. The changes of RBC-folate were greater in the 800 µg/day than in the 400 µg/day at any time (changes after 8 weeks: 566 ± 260 vs. 389 ± 229 nmol/L; p < 0.001). Significantly more women in the 800 µg group achieved desirable RBC-folate concentrations at 4 weeks (45.5 vs. 31.3%; p = 0.041) or 8 weeks (83.8 vs. 54.5%; p < 0.001) compared with the 400 µg group. RBC-folate levels below the population median (590 nmol/L) were associated with a reduced response to supplements. CONCLUSIONS: 88% of the women had insufficient RBC-folate to prevent birth defects, while 6.1% had deficiency. Women with low RBC-folate were unlikely to achieve desirable levels within 4-8 weeks, unless they receive 800 µg/day. The current supplementation recommendations are not sufficient in countries not applying fortification. TRIALS REGISTER: The trial was registered at The German Clinical Trials Register: DRKS-ID: DRKS00009770.


Assuntos
Suplementos Nutricionais , Eritrócitos/classificação , Ácido Fólico/administração & dosagem , Ácido Fólico/sangue , Defeitos do Tubo Neural/prevenção & controle , Adolescente , Adulto , Relação Dose-Resposta a Droga , Feminino , Alemanha , Humanos , Pessoa de Meia-Idade , Gravidez , Adulto Jovem
17.
J Clin Invest ; 128(2): 607-624, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29251628

RESUMO

Macrophages are a source of both proinflammatory and restorative functions in damaged tissue through complex dynamic phenotypic changes. Here, we sought to determine whether monocyte-derived macrophages (MDMs) contribute to recovery after acute sterile brain injury. By profiling the transcriptional dynamics of MDMs in the murine brain after experimental intracerebral hemorrhage (ICH), we found robust phenotypic changes in the infiltrating MDMs over time and demonstrated that MDMs are essential for optimal hematoma clearance and neurological recovery. Next, we identified the mechanism by which the engulfment of erythrocytes with exposed phosphatidylserine directly modulated the phenotype of both murine and human MDMs. In mice, loss of receptor tyrosine kinases AXL and MERTK reduced efferocytosis of eryptotic erythrocytes and hematoma clearance, worsened neurological recovery, exacerbated iron deposition, and decreased alternative activation of macrophages after ICH. Patients with higher circulating soluble AXL had poor 1-year outcomes after ICH onset, suggesting that therapeutically augmenting efferocytosis may improve functional outcomes by both reducing tissue injury and promoting the development of reparative macrophage responses. Thus, our results identify the efferocytosis of eryptotic erythrocytes through AXL/MERTK as a critical mechanism modulating macrophage phenotype and contributing to recovery from ICH.


Assuntos
Hemorragia Cerebral/patologia , Eritrócitos/classificação , Macrófagos/citologia , Animais , Apoptose , Lesões Encefálicas , Eritrócitos/citologia , Hematoma/metabolismo , Humanos , Imunidade Inata , Inflamação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fagocitose , Fenótipo , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Solubilidade , Resultado do Tratamento , c-Mer Tirosina Quinase/metabolismo , Receptor Tirosina Quinase Axl
18.
Phys Rev Lett ; 119(7): 078101, 2017 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-28949676

RESUMO

The capture of CO, a standard lung function test, results from diffusion-reaction processes of CO with hemoglobin inside red blood cells (RBCs). In its current understanding, suggested by Roughton and Forster in 1957, the capture is represented by two independent resistances in series, one for diffusion from the gas to the RBC periphery, the second for internal diffusion reaction. Numerical studies in 3D model structures described here contradict the independence hypothesis. This results from two different theoretical reasons: (i) The RBC peripheries are not equi-concentrations; (ii) diffusion times in series are not additive.


Assuntos
Monóxido de Carbono/farmacocinética , Eritrócitos/classificação , Hemoglobinas/química , Pulmão/fisiologia , Humanos , Modelos Teóricos
19.
Rev. bras. plantas med ; 18(1,supl.1): 341-348, 2016. tab, graf
Artigo em Português | LILACS | ID: lil-782984

RESUMO

RESUMO Tivemos como objetivo avaliar o efeito da infusão de Cunila microcephala Benth sobre a atividade da enzima acetilcolinesterase (AChE) e marcadores de estresse oxidativo em eritrócitos de agricultores. Foram utilizadas amostras provenientes de 16 trabalhadores rurais expostos a pesticidas agrícolas pelo período mínimo de 5 anos e um grupo controle constituído de 16 indivíduos não expostos a agrotóxicos. As hemácias dos agricultores e o grupo A foram expostos “in vitro” à solução salina (NaCl 0,9%). Os demais grupos foram expostos à infusão de poejo nas concentrações de 0; 5; 10; 25 e 50 g/L (Grupos B; C; D e E, respectivamente). Em seguida, foram realizadas as determinações da atividade da AChE e dos níveis de substâncias reativas ao ácido tiobarbitúrico (TBARS), proteínas carboniladas (PCs) e glutationa reduzida (GSH). Os resultados mostram que a infusão de poejo 50g/L, aumenta a atividade da enzima AChE e os níveis de GSH. Contudo, os níveis de TBARS e PCs diminuíram após o tratamento com a infusão de poejo 25 e 50 g/L. A infusão de poejo, na concentração de 50 g/L, é capaz de reverter, “in vitro” a inibição da atividade da AChE que ocorre pela exposição a pesticidas, e ainda demonstra um importante potencial antioxidante, tendo em vista que diminuiu danos lipídicos e proteicos e ainda, estimulou a produção do principal antioxidante não enzimático endógeno.


ABSTRACT Evaluating the effect of infusion Cunila microcephala Benth on acetylcholinesterase activity (AChE) enzyme and on biomarkers of oxidative stress in farmers erythrocytes. We used samples from 16 rural workers exposed to pesticides for a minimum of five years, and a control group composed of 16 individuals not exposed to pesticides. The erythrocytes of farmers and from group A were exposed “in vitro” the saline solution (NaCl 0,9%). The other groups were exposed to the infusion of “poejo” at concentrations of 0; 5; 10; 25 and 50 g/L (Groups B, C, D and E, respectively). Then, it was realized the analitical determinations of AChE activity and TBARS, PCs and GSH levels. The results showed that “poejo” infusion 50g/L, increased the AChE activity and GSH levels. However, the TBARS e PCs levels decreased after the treatment with “poejo” infusion 25 e 50 g/L. The “poejo” infusion 50 g/L is able to revert “in vitro” the inhibition of AChE activity that occurs by exposure to pesticides and also demonstrates an important antioxidant potential, given that decreased lipid and protein damage and also it stimulated the production of the main non-enzymatic antioxidant endogenous.


Assuntos
Humanos , Acetilcolinesterase/farmacologia , Técnicas In Vitro/instrumentação , Biomarcadores/análise , Estresse Oxidativo , Lamiaceae/classificação , Praguicidas , Eritrócitos/classificação , Fazendeiros/classificação
20.
Lancet Haematol ; 2(7): e282-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26207259

RESUMO

BACKGROUND: When problems with compatibility arise, transfusion services often use time-consuming serological tests to identify antigen-negative red cell units for safe transfusion. New methods have made red cell genotyping possible for all clinically relevant blood group antigens. We did mass-scale genotyping of donor blood and provided hospitals with access to a large red cell database to meet the demand for antigen-negative red cell units beyond ABO and Rh blood typing. METHODS: We established a red cell genotype database at the BloodCenter of Wisconsin on July 17, 2010. All self-declared African American, Asian, Hispanic, and Native American blood donors were eligible irrespective of their ABO and Rh type or history of donation. Additionally, blood donors who were groups O, A, and B, irrespective of their Rh phenotype, were eligible for inclusion only if they had a history of at least three donations in the previous 3 years, with one donation in the previous 12 months at the BloodCenter of Wisconsin. We did red cell genotyping with a nanofluidic microarray system, using 32 single nucleotide polymorphisms to predict 42 blood group antigens. An additional 14 antigens were identified via serological phenotype. We monitored the ability of the red cell genotype database to meet demand for compatible blood during 3 years. In addition to the central database at the BloodCenter of Wisconsin, we gave seven hospitals online access to a web-based antigen query portal on May 1, 2013, to help them to locate antigen-negative red cell units in their own inventories. FINDINGS: We analysed genotype data for 43,066 blood donors. Requests were filled for 5661 (99.8%) of 5672 patient encounters in which antigen-negative red cell units were needed. Red cell genotyping met the demand for antigen-negative blood in 5339 (94.1%) of 5672 patient encounters, and the remaining 333 (5.9%) requests were filled by use of serological data. Using the 42 antigens represented in our red cell genotype database, we were able to fill 14,357 (94.8%) of 15,140 requests for antigen-negative red cell units from hospitals served by the BloodCenter of Wisconsin. In the pilot phase, the seven hospitals identified 71 units from 52 antigen-negative red cell unit requests. INTERPRETATION: Red cell genotyping has the potential to transform the way antigen-negative red cell units are provided. An antigen query portal could reduce the need for transportation of blood and serological screening. If this wealth of genotype data can be made easily accessible online, it will help with the supply of affordable antigen-negative red cell units to ensure patient safety. FUNDING: BloodCenter of Wisconsin Diagnostic Laboratories Strategic Initiative and the NIH Clinical Center Intramural Research Program.


Assuntos
Bancos de Sangue/organização & administração , Antígenos de Grupos Sanguíneos/genética , Tipagem e Reações Cruzadas Sanguíneas , Eritrócitos/classificação , Técnicas de Genotipagem , Doadores de Sangue , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Wisconsin
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