21 results on '"Haemoglobin"'
Search Results
2. [Evaluation of a new portable analyzer, HemoCue ® Hb801, for hemoglobin point-of-care testing].
- Author
-
Zamorano B, Sakr Y, and Galopin-Dubois F
- Subjects
- Humans, Hemoglobinometry methods, Point-of-Care Systems, Hemoglobins analysis, Point-of-Care Testing
- Abstract
The use of portable hemoglobin measuring devices is widespread. In this context, the company HemoCue® has put on the market a new device, the Hb801. It uses a whole blood absorbance measurement method and not the azidmethemoglobin measurement method used by HemoCue's older devices. We evaluated this new equipment on EDTA venous blood. Hb801 is lightweight, compact, requires a volume of 10 μL of blood and renders its result in less than a second. The repeatability and intermediate precision are close to the values expected according to Ricos, with coefficients of variation respectively for a low level of hemoglobin: 2.1% and 1.9%, for an average level: 0.8% and 1.5% and for a high level: 1.5% and 1.3%. Comparison to our laboratory reference method (XN-10 Sysmex®) and HemoCue® Hb201+ was performed on 96 samples. Bias (SD) found were: XN-10: +0.42 g/dL (0.17), HemoCue® Hb201+: +0.17 g/dL (0.41). Clinically acceptable performance (within ± 1 g/dL of reference hemoglobin) was high: 93.8%. In the end, this device seems to us to be suitable for hemoglobin point-of-care testing.
- Published
- 2024
- Full Text
- View/download PDF
3. Distribution of haemoglobin genotypes, knowledge, attitude and practices towards sickle cell disease among unmarried youths in the Buea Health District, Cameroon
- Author
-
Nini Yesih Ngwengi, Peter Nde Fon, and Dora Mbanya
- Subjects
haemoglobin ,knowledge ,attitude ,practice ,sickle cell disease ,Medicine - Abstract
INTRODUCTION: Sickle cell disease (SCD) is one of the commonest genetic causes of morbidity and mortality in the world. In resource-limited settings, SCD prevention through public education and screening could be a significant strategy to curb its prevalence. The study aimed at determining the distribution of haemoglobin genotypes among unmarried youths in Buea, Cameroon as well as their knowledge, attitude and practices towards SCD. METHODS: a community-based, analytic, cross-sectional study was conducted within the city of Buea. Data was collected from 410 youths using self-administered questionnaires. Of the 410 youths, 100 were selected by purposive random sampling and their haemoglobin genotyping was done using haemoglobin electrophoresis. The data was analysed using the statistical software Epi Info Version 7. RESULTS: the majority (51.5%) of the 410 respondents were females. The modal age range was 18- 21 years (46.8%) and 60.4% had tertiary education. Less than one quarter (20.5%) had good knowledge of SCD. Only 13.2% knew their genotype and 59.3% were willing to avoid carrier marriages. Out of the 100 participants for genotyping, 84.0% had normal haemoglobin (HbAA) and 16.0% had the sickle cell trait (HbAS). CONCLUSION: most of the respondents had moderate knowledge of SCD. Only a few knew their haemoglobin genotype and more than half were willing to avoid carrier marriages. The prevalence of sickle cell trait is high in Buea. The promotion of preventive methods like public education and genetic screening is recommended to reduce the burden of SCD in Cameroon.
- Published
- 2020
- Full Text
- View/download PDF
4. Prévention de l’anémie chez les donneurs de sang.
- Author
-
Fillet, A.-M. and Gross, S.
- Abstract
Résumé La prévention de l’anémie du donneur de sang est un enjeu essentiel pour la sécurité du donneur mais aussi pour l’autosuffisance quantitative et qualitative en produits sanguins labiles. Cette prévention repose, d’une part, sur l’ajournement des donneurs dont le taux d’hémoglobine est en dessous du seuil réglementaire, et d’autre part, sur la prévention de la carence en fer. Des populations de donneurs sont plus à risque de carence en fer et des conséquences cliniques de cette carence : les femmes en âge de procréer ; les donneurs dont le taux d’hémoglobine est juste au-dessus du seuil d’éligibilité et ceux qui donnent fréquemment. Plusieurs mesures peuvent être utilisées : l’accroissement de l’intervalle minimal entre deux dons de ST et/ou la réduction de la fréquence annuelle maximale de dons ; le dosage de la ferritine sérique mesurant les réserves en fer et enfin la supplémentation en fer des donneurs. The prevention of anemia of blood donor is a main issue for donor safety and self-supplying. This prevention is done in one hand by donor deferral whose haemoglobin level is under defined threshold and in other hand by preventing iron deficiency. Some subgroups of donors are at increased risk for developing iron deficiency and adverse effects of iron deficiency: premenopausal females; donors with haemoglobin values near the minimum for eligibility and frequent donors. Different interventions could be used: lengthening the inter-donational interval and/or decreasing the number of donations per year; donor ferritin testing to evaluate iron store and at least donor iron supplementation. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
5. Assessment of iron status among preschool children (6 to 59 months) with and without malaria in Western Province, Kenya
- Author
-
Isaac Kisiangani, Charles Mbakaya, Anzelimo Makokha, and Dennis Magu
- Subjects
serum ferritin ,haemoglobin ,plasmodium falciparum malaria ,preschool children ,Medicine - Abstract
INTRODUCTION: iron deficiency is a major public health concern. Globally, iron deficiency ranks number 9 and is responsible for about 60% of all anemia cases among preschool children. In Africa iron deficiency is 43-52% while in Kenya, children under 5 years constitute the largest burden with 69% of them being deficient. There is limited iron deficiency data in Kenya. This study determined haemoglobin levels, serum ferritin levels, nutritional status and P.falciparum malaria infection in preschool children.
- Published
- 2015
- Full Text
- View/download PDF
6. Incidence and predictors of recovery from anaemia within an HIV-infected South African Cohort, 2004-2010
- Author
-
Zibusiso Ndlovu, Tobias Chirwa, and Simbarashe Takuva
- Subjects
haemoglobin ,human immunodeficiency virus ,aids ,themba lethu clinical cohort ,antiretroviral therapy ,Medicine - Abstract
INTRODUCTION: Anaemia is one of the most frequent haematological complications in HIV-infected persons. Understandingfactors associated with recovery from anaemia during ART is vital in improving clinical outcomes since anaemia is a strong predictor of mortality. METHODS: Cohort study of 12,441 HIV-infected adults initiating ART between 2004- 2010 in Johannesburg, South Africa. A further 2,489 patients with prevalent anaemia at ART initiation were examined to determine the incidence and predictors of recovery from anaemia. Cox proportional hazards models were fitted to investigate predictors of recovery from anaemia. RESULTS: Of the 2,489 patients with prevalent anaemia, most patients (n=2,225, 89.4%) recovered from anaemia. Median time to anaemia recoverywas 3.9 months (IQR: 3.22-6.20) and incidence rate was 180 per 100person years (95% CI: 172-187). In univariateanalysis, sex, CD4 count, BMI, WHO stage, employment status, smoking status and presence of tuberculosis at initiation ofART were significant predictors of recovery from anaemia. However in multivariateanalysis, predictors of recovery from anaemia were: male sex- HR: 1.43 (95% CI: 1.29-1.59) p=0.001, advanced WHO stage III/IV - HR: 1.17 (95% CI: 1.07-1.29) p=0.001). There was no significant association with CD4 count in multivariate analysis. CONCLUSION: A large proportion of HIV infected patients with anaemia at baseline recover early during the course of ART. Females and those with less advanced WHO stage seem to be at higher risk of poor recovery from anaemia. Understanding the predictors for poor recovery from anaemia would allow closer follow-up and more targeted interventions thus reducing excess anaemia and mortality burden.
- Published
- 2014
- Full Text
- View/download PDF
7. Cord blood full blood count parameters in Lagos, Nigeria
- Author
-
Adediran Adewumi, Adeyemo Titilope A, Akinbami A Akinsegun, Gbadegesin Abidoye, Uche Ebele, and Akanmu A Sulaimon
- Subjects
haemoglobin ,cord blood ,stem cell ,umbilical cord ,neonatologist ,Medicine - Abstract
INTRODUCTION: Full blood count (FBC), one of the most frequently requested for laboratory investigations, is a simple, fast and cheap test and is a reliable indicator of health. Due to its usefulness in the assessment of health status of individuals, its parameters in cord blood, a major source of haemopoietic stem cell transplantation and an ideal source for laboratory investigations for newborns were determined to provide a useful guide to local neonatologists and stem cell transplant physicians. METHODS: Three millilitres of umbilical cord blood was collected from 130 normal birth weight newborns (69 males and 61 females) whose cord were clamped immediately after delivery, at a teaching hospital in Lagos, Nigeria and full blood count parameters were determined using Sysmex autoanalyzer, model KX-21N. Consented mothers of the newborns were selected based on, age between 18 and 45 years; uneventful pregnancy and delivery and haemoglobin (Hb) concentration e" 10 g/dL. RESULTS: There were no statistical gender differences in the mean values of Hb concentrations (M=13.27 ,1.60 g/dL; F=13.32,1.61g/dL; p=0.93), total white cell count (M=3.16,5.43 , 109/L; F=13.07,4.98 , 109/L; p= 0.92), platelet count (M= 223.64, 64.21 , 109/L; F=226.69,80.83 , 109/L; p=0.81) and other parameters. CONCLUSION: Mean values of full blood count parameters obtained in this study are comparable to reports from other studies in developing countries and could be a useful guide for neonatologists and stem cell transplant physicians in our geographical location.
- Published
- 2014
- Full Text
- View/download PDF
8. Assessment of iron status among preschool children (6 to 59 months) with and without malaria in Western Province, Kenya.
- Author
-
Kisiangani, Isaac, Mbakaya, Charles, Makokha, Anzelimo, and Magu, Dennis
- Subjects
- *
PRESCHOOL children , *IRON deficiency anemia , *MALARIA , *HEALTH - Abstract
Introduction: Iron deficiency is a major public health concern. Globally, iron deficiency ranks number 9 and is responsible for about 60% of all anemia cases among preschool children. In Africa iron deficiency is 43-52% while in Kenya, children under 5 years constitute the largest burden with 69% of them being deficient. There is limited iron deficiency data in Kenya. This study determined haemoglobin levels, serum ferritin levels, nutritional status and P.falciparum malaria infection in preschool children. Methods: A household cross sectional study was undertaken among 125 preschoolers in Western province, drawn from 37 clusters. Systematic random sampling was used for sample selection. Data was collected using pretested structured questionnaires, entered in Microsoft package. Data analysis was done in Statistical package for social science (SPSS) version 20 using bivariate and multivariate logistic regression and differences were considered significant at P < 0.05. Results: The prevalence of iron deficiency (Serum ferritin <12mg/l), anaemia (Hb<110g/l) and plasmodium falciparum malaria were 20.8%, 25% and 6.8% respectively. There was a significant association between iron deficiency and anaemia (OR=3.43, 95% CI: 1.33-8.84, p=0.008). A preschool child with anaemia was 3.43 times likely to be iron deficient compared to a preschool child who was not anaemic. Conclusion: Iron deficiency, anaemia and plasmodium falciparum malaria was prevalent among preschool children. The findings revealed a significant association between iron deficiency and anaemia. Therefore effective interventions to improve iron status will have large health benefits by greatly reducing anaemia in preschool children. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
9. Faisabilité de la stratégie d’administration de la darbepoetin alfa tous les 15 jours : expérience 2005–2007 d’un centre de dialyse.
- Author
-
Rottembourg, Jacques B. and Dansaert, Aurélie
- Subjects
UNITS of measurement ,ERYTHROPOIESIS ,HEMODIALYSIS ,MEDICAL protocols ,ANEMIA treatment ,FEASIBILITY studies - Abstract
Copyright of Néphrologie & Thérapeutique is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2011
- Full Text
- View/download PDF
10. Prévalence de l’anémie ferriprive au cours de la grossesse dans la wilaya de Blida (Nord de l’Algérie)
- Author
-
Bitam, Arezki and Belkadi, Naima
- Subjects
- *
DURATION of pregnancy , *ANEMIA in pregnancy , *PREGNANCY complications , *NUTRITION disorders , *THERAPEUTIC use of iron , *PREVENTION - Abstract
Abstract: The study was carried out among 90 pregnant women divided equitably into three groups (30 pregnant women of three months and 30 of pregnant women of six months, 30 of other pregnant women of nine months) recruited at the hospital and a private laboratory located at Blida near Algiers. The definite World Health Organisation anemia at the pregnant women showing lower rate has 11g/dl. The prevalence of martial deficiency is 10% for groups G1 and G2 and G3 respectively. The results showed us a high prevalence of anaemia (10%, 33.33%, 46.66%) for the three, six and nine month of pregnancy. The prevalence of anaemia is all the more high as the age of the pregnancy is more advanced. However, it appears essential to consider a program of systematic iron supplementation from the second quarter of the pregnancy. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
11. Détermination de l'hémoglobine plasmatique et évaluation spectrophotométrique de lhemolyse en biochimie clinique.
- Author
-
Mezzou, Hicham, Khelifa, Anis Belhaj, Neffati, Fadoua, Douki, Wahiba, Amor, Adel Ben, and Najjar, Mohamed Fadhel
- Subjects
HEMOGLOBINOMETRY ,HEMOGLOBINS ,TRIGLYCERIDES ,BILIRUBIN ,SPECTROMETERS ,SPECTROPHOTOMETRY - Abstract
Copyright of Revue Francophone des Laboratoires is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2006
- Full Text
- View/download PDF
12. Électrophorèse capillaire et hémoglobinopathies.
- Author
-
Cotton, F., Vertongen, F., and Gulbis, B.
- Subjects
CAPILLARY electrophoresis ,ELECTROPHORESIS ,SEPARATION (Technology) ,LIQUID chromatography ,HEMOGLOBINS - Abstract
Copyright of IBS, Immuno-analyse & Biologie Specialisee is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2006
- Full Text
- View/download PDF
13. Oxygen transport enhancing agents: methods and strategies of detection
- Author
-
Audran, M. and Varlet-Marie, E.
- Subjects
- *
ENDURANCE sports , *PHYSIOLOGICAL transport of oxygen , *OXYGEN in the body , *SPORTS , *RECOMBINANT erythropoietin , *THERAPEUTICS - Abstract
Aims. – Draw up the inventory of various methods able to increase the oxygen transport by the blood and present methods and strategy of detection.Current knowledge. – Maximal oxygen uptake is the major performance limiting factor in endurance sports. Sophisticated training methods have been developed to increase this variable. On the other hand, attempts have been made to improve maximal oxygen uptake by artificial means: blood doping, administration of human recombinant erythropoietin (rhu-Epo) and, probably, by the use of a new class of therapeutic agents: the artificial oxygen carriers. All these substances and methods are prohibited by the International Olympic Committee. But, until now, the detection of the misuse of these compounds is a problem: there is no detection method for blood doping, the current test method for rhu-Epo can do false negative cases and no screening methods are performed for oxygen carriers.Points of views and plans. – Despite the emergence of the oxygen carriers, in fact easy to detect, the use of r-HuEpo seems the most efficient practice. Today there is a test to detect abuse of r-HuEpo, that’s why the cheats should have recourse to red blood cells transfusion. However concomitant injections of r-HuEpo and GH or IL-3 should use least doses and so to make the detection more difficult. Although indirect methods will be refined, this approach will likely insufficient by itself. A careful definition of an individual’s hematologic profile, the so-called “hematologic passport”, should form the basis for a more successful application of any indirect method and should disturb recourse to doping. [Copyright &y& Elsevier]
- Published
- 2004
- Full Text
- View/download PDF
14. Haemoglobin from microorganism to man: a single protein folding, a variety of functions.
- Author
-
Wajcman, Henri and Kiger, Laurent
- Subjects
- *
HEMOGLOBINS , *PEPTIDES , *OXYGEN - Abstract
Haemoglobins from unicellular organisms, plants or animals, share a common structure, which results from the folding, around the heme group, of a polypeptide chain made from 6–8 helices. Nowadays, deciphering the genome of several species allows one to draw the evolutionary tree of this protein going back to 1800 millions of years, at a time when oxygen began to accumulate in the atmosphere. This permits to follow the evolution of the ancestral gene and of its product. It is likely that, only in complex multicellular species, transport and storage of oxygen became the main physiological function of this molecule. In addition, in unicellular organisms and small invertebrates, it is likely that the main function of this protein was to protect the organism from the toxic effect of O2, CO and NO•. The very high oxygen affinity of these molecules, leading them to act rather as a scavenger as an oxygen carrier, supports this hypothesis. Haemoglobins from microorganisms, which may probably be the closest vestiges to the ancestral molecules, are divided into three families. The first one is made from flavohaemoglobins, a group of chimerical proteins carrying a globin domain and an oxido-reduction FAD-dependant domain. The second corresponds to truncated haemoglobins, which are hexacoordinated with very high oxygen-affinity molecules, 20–40 residues shorter than classical haemoglobins. The third group is made from bacterial haemoglobins such as that of Vitreoscilla. Some specific structural arrangements in the region surrounding the heme are cause of their high oxygen affinity. In plants, two types of haemoglobins are present (non-symbiotic and symbiotic), that arose from duplication of an ancestral vegetal gene. Non-symbiotic haemoglobins, which are probably the oldest, are scarcely distributed within tissues having high energetic consumption. Conversely, symbiotic haemoglobins (also named leghaemoglobins) are present at a high concentration (mM) mostly in the rhizomes of legumes, where they are involved in nitrogen metabolism. In some species, haemoglobin was proposed to be an oxygen sensor bringing to the organism information to adjust metabolism or biosynthesis to the oxygen requirement. Elsewhere haemoglobin may act as final electron acceptors in oxido-reduction pathways. Evolution of haemoglobin in invertebrates followed a large variety of scenarios. Some surprising functions as sulphide acquisition in invertebrates living near hydrothermal vents, or a role in the phototropism of worm need to be mentioned. In invertebrates, the size of haemoglobin varies from monomers to giant molecules associating up to 144 subunits, while in vertebrates it is always a tetramer. In some species, several haemoglobins, with completely different structure and function, may coexist. This demonstrates how hazardous may be to extrapolate the function of a protein from only structural data. [Copyright &y& Elsevier]
- Published
- 2002
15. Hémorragies du post-partum non diagnostiquées : recherche fondée sur la variation du taux d'hémoglobinémie auprès de 3282 patientes
- Author
-
Duchenoy, Aude, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and François Jathières
- Subjects
Hémoglobine ,Erreur médicale ,Post-partum haemorrhage ,Hémorragie du postpartum ,Hémorragie de la délivrance ,Haemoglobin ,[SDV.MHEP.GEO]Life Sciences [q-bio]/Human health and pathology/Gynecology and obstetrics ,Blood loos ,Medical error ,Non diagnostique ,Perte sanguine ,Undiagosed ,Post-partum - Abstract
Introduction / Objective: Post-partum haemorrhage (PPH) is defined as bleeding more than 500mL within 24 hours after the delivery. In France it concerns 5 to 10% of the delivery. .Other studies show an underestimation of blood loss.Methods: We carried an observational retrospective study in a type 3 maternity in Ile de France. Inclusion criteria were a single pregnancy, who delivered vaginally after 37 weeks gestation. Our diagnostic criteria for undiagnosed PPH (UDPPH) was a change in blood haemoglobin greater than 2g/dl. We compared characteristics of the controle's groupe and the diagnosed PPHs groupe, with the undiagnosed PPHs groupe. Results The incidence of undiagosed PPH in our population was 9.5%.Risk factors associated with UDPPH were: instrumental delivery, episiotomy, epidural anaesthesia, oxytocine, primiparity, multipara with previous cesariean and hyperthermia during labor.Conclusion: The use of systematic screening may allow an assessment of professional practices. But the usefulness of systematic prevention in long term compared to targeted prevention needs to be sought.; Introduction / Objectifs : L'hémorragie du post-partum (HPP) est définie comme une perte sanguine supérieure à 500 ml dans les 24 heures qui suivent l'accouchement. Elle concerne en France 5 à 10% des accouchements. Certaines études antérieures montrent qu'il y a une sous estimation des pertes sanguines comprise entre 20 et 62%.Matériel et méthodes : Nous avons réalisé une étude observationnelle rétrospective au sein d'une maternité de type 3 en Île de France. Les critères d'inclusion étaient des patientes singletons, ayant accouché par voie basse à un terme supérieur ou égale à 37 semaines d'aménorrhées. Notre critère de diagnostique des HPP non diagnostiquées (HPPND) était une variation de l'hémoglobine sanguine de plus de 2g/dl. Une comparaison des caractéristiques du groupe témoin et du groupe des HPP diagnostiquées a été réalisée par rapport au groupe des HPP non diagnostiquées.Résultats : L'incidence des HPP non diagnostiquées au sein de notre population était de 9.5%. Les facteurs de risques d'HPPND mis en exergue sont : l'utilisation d'instrument, la pratique d'épisiotomie, l'analgésie péridurale et l'utilisation d'oxytocine, les patientes primipares, l'antécédent d'utérus cicatriciel chez les multipares et l'hyperthermie pendant le travail. Conclusion : La pratique d'un dépistage systématique peut permettre une évaluation des pratiques professionnelles au sein d'un service. Mais l'utilité d'un dépistage systématique au long court par rapport à un dépistage ciblé est encore à rechercher.
- Published
- 2019
16. Détermination de métalloprotéines par dilution isotopique associée à la spectrométrie de masse à plasma induit afin d'assurer la traçabilité métrologique en biochimie clinique
- Author
-
PALOS, MARIE, Université de Pau et des Pays de l'Adour (UPPA), Laboratoire National de Métrologie et d'Essais [Trappes] (LNE ), Laboratoire de Chimie Analytique Bio-Inorganique et Environnement (LCABIE), Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS), UPPA, Pr. Florence PANNIER, and Dr. Paola FISICARO
- Subjects
ICPMS ,Hémoglobine ,[CHIM.ANAL]Chemical Sciences/Analytical chemistry ,Haemoglobin ,Metrology ,Isotope dilution ,Métrologie ,Dilution isotopique - Abstract
This work is based on the implementation of metrological protocols to ensure traceability to the International System of Units (SI) of analysis in clinical biochemistry. The main objective is to develop and validate primary reference methods for the analysis of iron (Fe) and haemoglobin (Hb) in biological fluids. In a first part, a double isotope dilution (ID) reference method associated with ICPMS for the analysis of total Fe in serum allowing a connection of the result to SI was developed. In a second part, three approaches to ID for the analysis of total Hb in hemolysate were studied. A first method consists of mineralizing the sample and applying the ID-ICPMS by determining the Hb concentration through the Fe content. This developed and validated method is promising, however, it remains limited to samples where no other ferric species must be present. Thus, the implementation of the elementary speciation analysis using the ID with the HPLC-ICPMS coupling is necessary. Two modes of elementary speciation are evaluated: the non-specific mode and the specific mode. The results are encouraging, however, additional work, in terms of accuracy, will have to be done in order to be able to use these methods for the assignment of reference values.; Ce travail repose sur la mise en œuvre de protocoles métrologiques permettant d’assurer la traçabilité au Système International des unités (SI) des analyses en biochimie clinique. L’objectif principal consiste à développer et à valider des méthodes de référence primaire pour l’analyse du fer (Fe) et de l’hémoglobine (Hb) dans des fluides biologiques. Dans une première partie, une méthode de référence par double dilution isotopique (ID) associée à l’ICPMS pour l’analyse du Fe total dans du sérum permettant un raccordement du résultat au SI a été mise au point. Dans une deuxième partie, trois approches de l’ID pour l’analyse de l’Hb totale dans de l’hémolysat ont été étudiées. Une première méthode consiste à minéraliser l’échantillon et à appliquer l’ID-ICPMS en déterminant la concentration en Hb à travers la teneur en Fe. Cette méthode développée et validée est prometteuse, cependant, elle reste limitée aux échantillons où aucune autre espèce ferrique ne doit être présente. Ainsi, la mise en place de l’analyse de spéciation élémentaire utilisant l’ID avec le couplage HPLC-ICPMS est nécessaire. Deux modes d’ID en spéciation élémentaire sont évalués : le mode non-spécifique et le mode spécifique. Les résultats sont encourageants, cependant, un travail supplémentaire, au niveau de la justesse, devra être effectué afin de pouvoir utiliser ces méthodes pour l’assignation de valeurs de références.
- Published
- 2016
17. [Use of « Reference change value » in medical biology: about two examples: total PSA and hemoglobin].
- Author
-
Bouverot C, Blachier S, Roquigny N, and Guerber F
- Subjects
- Automation, Laboratory instrumentation, Automation, Laboratory standards, Data Interpretation, Statistical, Diagnostic Tests, Routine instrumentation, Diagnostic Tests, Routine methods, Female, Humans, Laboratory Proficiency Testing, Male, Meta-Analysis as Topic, Observer Variation, Prostatic Neoplasms blood, Prostatic Neoplasms diagnosis, Reference Standards, Reference Values, Reproducibility of Results, Sensitivity and Specificity, Biological Variation, Individual, Clinical Laboratory Services standards, Diagnostic Tests, Routine standards, Hemoglobins analysis, Prostate-Specific Antigen analysis
- Abstract
The interpretation of the variation between the results of two dosages performed on the same patient is generally quite empirical. It is usually based on the experience of the biologist or physician. Through two examples, total PSA and hemoglobin, we hoped to set up an indicator of the significance variation between results: The Reference change value or RCV to provide assistance to the validator biologist and prescriber based on measured statistical arguments. This article describes the methodology used for the RCV calculation, the formatting on analysis reports and the limitations of the system.
- Published
- 2020
- Full Text
- View/download PDF
18. Les dérivées de l’hémoglobine dans la structure rétinienne par la technique de réflectométrie multi-spectrale
- Author
-
Vucea, Valentina and Diaconu, Vasile
- Subjects
Hémoglobine ,Oximeter ,Oxymétrie ,Retinal blood vessels ,Spectrophotométrie ,Concentration d’oxygène ,Modélisation ,Spectrophotometry ,Oxygen concentration ,Oxyhaemoglobin ,Vaisseaux sanguins rétiniens ,Haemoglobin ,Oxyhémoglobine ,Model - Abstract
L’examen de la rétine par des moyens non invasifs et in vivo a été un objectif de recherche pendant plusieurs années. Pour l’œil comme pour tous les organes du corps humain, un apport soutenu en oxygène est nécessaire pour le maintien de l’homéostasie. La concentration en oxygène du sang des vaisseaux rétiniens peut être déterminée principalement à partir des mesures du spectre de réflexion du fond de l’œil. En envoyant une lumière, à différentes longueurs d’onde, sur la rétine et en analysant la nature de la lumière réfléchie par la rétine, il est possible d’obtenir des informations quantitatives sur le niveau d'oxygène dans les vaisseaux sanguins de la rétine ou sur le flux sanguin. Cependant, la modélisation est compliquée due aux différentes interactions et aux chemins que la lumière prend à travers les tissus oculaires avant de quitter l’œil. L’objectif de cette thèse a été de développer et de valider un modèle mathématique afin de calculer les dérivées d’hémoglobine à partir de mesures spectrales de réflectométrie sur les vaisseaux sanguins de la rétine. L’instrument utilisé pour mesurer la fonction spectrale de réflectométrie a été un spectroréflectomètre multi-canal, une technologie capable de mesurer in vivo et en continu 800 spectres simultanément. L'équation mathématique qui décrit la fonction spectrale de réflectométrie dans la zone spectrale de 480 nm à 650 nm a été exprimée comme la combinaison linéaire de plusieurs termes représentant les signatures spectrales de l'hémoglobine SHb, de l'oxyhémoglobine SOHB, l’absorption et la diffusion des milieux oculaires et une famille de fonctions multigaussiennes utilisées pour compenser l’incompatibilité du modèle et les données expérimentales dans la zone rouge du spectre. Les résultats du modèle révèlent que le signal spectral obtenu à partir de mesures de réflectométrie dans l’œil est complexe, contenant la lumière absorbée, réfléchie et diffusée, mais chacun avec une certaine prédominance spécifique en fonction de la zone spectrale. La fonction spectrale d’absorption du sang est dominante dans la zone spectrale 520 à 580 nm, tandis que dans la zone spectrale de longueurs d’ondes plus grandes que 590 nm, la diffusion sur les cellules rouges du sang est dominante. Le modèle a été utilisé afin de mesurer la concentration d’oxygène dans les capillaires de la tête du nerf optique suite à un effort physique dynamique. L’effort physique a entraîné une réduction de la concentration d’oxygène dans les capillaires, ainsi qu’une réduction de la pression intraoculaire, tandis que la saturation sanguine en oxygène, mesurée au niveau du doigt, restait constante. Le modèle mathématique développé dans ce projet a ainsi permis, avec la technique novatrice de spectroréflectométrie multicanal, de déterminer in vivo et d’une manière non invasive l’oxygénation sanguine des vaisseaux rétiniens., In vivo retinal exams done through non-invasive methods have been an objective for researchers these past years. The eye, just like any other organ in the human body, has a constant need of oxygen in order to maintain homeostasis. The concentration of oxygen present in the retinal blood vessels can be determined mainly by measurements of spectral reflections of the fundus. By sending rays of light at different wavelengths on the retina and analyzing the nature of the reflected light, it is possible to obtain quantitative information on the level of oxygen found in the blood vessels of the retina. However, the establishment of a model is complicated due to the different interactions and pathways taken by the light when passing through the different ocular tissues before leaving the eye. The objective of this thesis has been to develop and validate a mathematical model that calculates the derivatives of haemoglobins by using spectral measurements of reflectometry on the retinal blood vessels. The instrument used to measure the spectral function of reflectometry was a multichannel spectroreflectometer, a technology capable of measuring continuously and simultaneously 800 spectral in vivo. The mathematical equation describing the spectral function of reflectometry in the spectral zone ranging from 480 nm to 650 nm, has been formulated to include the linear combination of multiple terms representing the spectral signatures of haemoglobin SHb, the oxyhaemoglobin SOHB, the absorption and diffusion of ocular media, and a family of multigaussian functions used to compensate the incompatibility of the model and the experimental results in the red zone of the spectral. The results of the model reveal that the spectral signal obtained by the measurements of reflectometry in the eye are complex, such as light absorption, reflection and diffusion, but that each has a specific predominance depending on the spectral zone. The spectral function describing blood absorption is dominant in the 520 to 580 nm spectral zone, whereas diffusion on red blood cells is dominant in the spectral zone containing higher wavelengths starting at 590 nm. The model was used to measure the concentration of oxygen in the microcapillaries found in the optic nerve head following a dynamic physical effort. The physical effort caused a reduction in the concentration of oxygen in the microcapillaries and a reduction of the intraocular eye pressure, whereas the blood saturation of oxygen measured in the finger remained constant. The mathematical model developed in this project, combined with the innovative technique of multichannel spectroreflectometry, allowed to determine in a non-invasive in-vivo method, the oxygenation of the retinal blood vessels.
- Published
- 2013
19. Optical methods of biological tissues investigation. Spectrometry of cerebral tissu with small optical probes and Imaging by Optical Coherence Tomography
- Author
-
Bradu, Adrian and Bradu, Adrian
- Subjects
hemodynamique ,[PHYS.PHYS.PHYS-BIO-PH] Physics [physics]/Physics [physics]/Biological Physics [physics.bio-ph] ,resonant scanner ,SLO ,turbid media ,spectrometrie ,tomography ,hemodynamics ,haemoglobin ,tomographie ,coherence ,spectrometry ,OCT ,scanner resonant ,oxymetry ,confinement ,hemoglobine ,optical ,optique ,milieux troubles ,oxymetrie ,Monte Carlo ,coherente - Abstract
We present in this thesis two optical methods of biological media investigation. First, we present an investigation invasive technique of the deep cerebral tissues. This technique using small optical probes is based on the strong light backscattering by the biological tissues. Thus, the measured light attenuation contains information on scattering properties of the medium but also on chromophores' concentrations. As a result, it seems possible to envisage a method of direct observation of some physiological parameters as the tissue oxygen saturation or hemoglobine concentration. Second, we present an imaging technique of the biological tissues, particulary used for eye imaging: the optical coherence tomography. This technique is based on the coherence properties of the light. Thus, the interfernce of the light from the two arms of a Michaelson interferometer give a signal containing informations on the reflectivity of a spatial domain of the target limited by the coherence lenght of the light source. Using this approach we built and characterised a fast OCT system using a resonant scanner., Nous abordons dans ce memoire deux methodes d'exploration des tissus biologiques. Premierement nous presenterons une technique spectroscopique invasive d'investigation des tissus cerebraux profonds. Cette technique utilisant des sondes optiques en miniature tire partie de la forte retrodiffusion de la lumiere par les tissus biologiques. Ainsi, l'attenuation lumineuse qu'on mesure experimentallement contient des informations non seulement sur les proprietes de diffusion mais aussi sur les concentrations des chromophores qu'ils contiennent. Le resultat est la posibilite d'envisager la mise en oeuvre d'une methode d'observation directe de certains paramatres hemodynamiques dont la saturation tissulaire en oxygene ou la concentration en hemoglobine totale. Deuxiemement nous presenterons une methode d'imagerie des tissus biologiques en particulier de l'oeil: la tomographie optique coherente. Sa technique tire partie de proprietes de coherence de la lumiere. Ainsi, l'interference constructive des faisceux lumineux provenant de deux bras d'un interferometre de type Michelson donne naissance a un signal contenant des informations sur la reflectivite provenant d'un domaine spatial de la cible limite par la longueur de coherence de la source. En utilisant ces bases theoriques nous avons mis en oeuvre un system OCT rapide utilisant un scanner resonant.
- Published
- 2004
20. Damage control, hémoglobine et hypothermie
- Author
-
Mion, G., Le Noël, A., Mérat, S., Ausset, S., and De Rudnicki, S.
- Published
- 2012
- Full Text
- View/download PDF
21. [Importance of comorbidities in the anemia of COPD: Economic implications and 3-year survival analysis].
- Author
-
Menou A, Pain M, Pivette J, Chenivesse C, Magnan A, and Chambellan A
- Subjects
- Aged, Anemia complications, Anemia mortality, Blood Gas Analysis, Cardiovascular Diseases economics, Cardiovascular Diseases epidemiology, Cardiovascular Diseases mortality, Comorbidity, Female, France epidemiology, Humans, Male, Middle Aged, Prevalence, Prognosis, Pulmonary Disease, Chronic Obstructive complications, Pulmonary Disease, Chronic Obstructive mortality, Respiratory Function Tests, Retrospective Studies, Survival Analysis, Anemia economics, Anemia epidemiology, Health Care Costs, Pulmonary Disease, Chronic Obstructive economics, Pulmonary Disease, Chronic Obstructive epidemiology
- Abstract
Introduction: Anemia occurs commonly in COPD and is associated with a poor prognosis. The role of comorbidities in this is suspected but poorly characterized and the economic implications of anemia combined with COPD in France have not been studied. The healthcare resource utilization and cost impact of anemia remain to be investigated., Methods: One hundred and fifty-one COPD patients attending a pulmonology outpatient department during a 6 months period were retrospectively selected if they had undergone a pulmonary function test, a blood gas analysis or a blood count. The Charlson comorbidity index, resource utilization and economic data from the year before the diagnosis of anemia were compared between anemic and non-anemic patients as well as 3-year survival analysis., Results: The prevalence of anemia was 18.5% and was not influenced by GOLD stage. The identification of anemia was similar from blood gas results and full blood count analysis. Comorbidities - mainly cardiovascular - were found in 86% of the anemic patients. The Charlson index was 5.4±2 in the anemic group compared to 4.1±1.5 in the non-anemic group (P<0.01). The Charlson index was the only predictive factor of anemia using logistic regression analysis. The 3-year mortality was 36% in the anemic versus 7% in the non-anemic group (P<0.05). The main factor identified which predicted 3-year mortality was the presence of anemia using logistic regression. Healthcare costs the year prior to the diagnosis of anemia were not significantly different between groups, but there was a tendency to an increase in the cost of the hospitalizations in the anemic group., Conclusions: Anemia is easy to diagnose in COPD from the blood gas analysis. It is frequently linked to the presence of comorbidities - mainly cardiovascular diseases - and is the more important predictive factor of the 3-year mortality. There was a tendency towards an increase in the costs of hospitalizations in anemic patients but this remains to be confirmed in a larger economic study., (Copyright © 2015 SPLF. Published by Elsevier Masson SAS. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.