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1.
Faraday Discuss ; 197: 403-419, 2017 04 28.
Article in English | MEDLINE | ID: mdl-28186515

ABSTRACT

Fischer-Tropsch synthesis was conducted in a small channel compact heat exchange reactor that was constructed of aluminum. While limited to lower temperature-pressure regions of the Fischer-Tropsch synthesis, the reactor could be operated in an isothermal mode with nearly a constant temperature along the length of the channel. The results obtained with the compact heat exchange reactor were similar to those obtained in the isothermal continuous stirred tank reactor, with respect to both activity and selectivity. Following a planned or unplanned shutdown, the reactor could be restarted to produce essentially the same catalytic activity and selectivity as before the shutdown.

2.
Patient Educ Couns ; 99(4): 542-548, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26796067

ABSTRACT

OBJECTIVE: To examine spoken interactions between pediatricians and community-based interpreters speaking with adolescents and parents with Limited English proficiency (LEP) in primary care to identify the challenges of interpreting in a four-person or tetradic visit, its sources of co-constructed errors, and specific practices for educational intervention. METHODS: As part of a larger study of vaccine decision-making at six clinical sites in two states, this descriptive study used discourse analysis to examine 20 routine primary care visits in a Latino Clinic in interactions between adolescents, parents, community-based interpreters, and pediatricians. Specific patterns of communication practices were identified that contributed to inaccuracies in medical interpretation RESULTS: Practices needing improvement were tallied for simple frequencies and included: omissions; false fluency; substitutions; editorializing; added clarification, information, or questions; medical terminology; extra explanation to mother; and, cultural additions. Of these speaking practices, omissions were the most common (123 out of 292 total) and the most affected by pediatricians. CONCLUSION: The dynamics of both pediatricians and interpreters contributed to identification of areas for improvement, with more adolescent participation in bilingual than monolingual visits. PRACTICE IMPLICATIONS: These observations provide opportunities for mapping a communication skills training intervention based on observations for future testing of an evidence-based curriculum.


Subject(s)
Communication Barriers , Hispanic or Latino/psychology , Language , Parents/psychology , Pediatrics , Physician-Patient Relations , Translating , Adolescent , Adult , Ambulatory Care Facilities , Child , Female , Humans , Male , Middle Aged , Mothers , Multilingualism , Primary Health Care
3.
Cytometry B Clin Cytom ; 86(1): 44-55, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23922226

ABSTRACT

BACKGROUND: Recent Flow Cytometric guidelines to detect Paroxysmal Nocturnal Hemoglobinuria (PNH) in white blood cells recommend using FLAER-based assays to detect granulocytes and monocytes lacking expression of GPI-linked structures. However national proficiency testing results continue to suggest a need for improved testing algorithms, including the need to optimize diagnostic analytes in PNH. METHODS: CD157 is another GPI-linked structure expressed on both granulocytes and monocytes and here we assess its ability to replace CD24 and CD14 in predicate 4-color granulocyte and monocyte assays respectively. We also assess a single tube, 5-color combination of FLAER, CD157, CD64, CD15, and CD45 to simultaneously detect PNH clones in granulocyte and monocyte lineages. RESULTS: Delineation of PNH from normal phenotypes with 4- or 5-color CD157-based assays compared favorably with 4-color predicate methods and PNH clone size data were similar and highly correlated (R(2) >0.99) with predicate values over a range (0.06%-99.8%) of samples. Both CD157-based assays exhibited similar high levels of sensitivity and low background levels in normal samples. CONCLUSIONS: While CD157-based 4- and 5-color assays generated closely similar results to the predicate assays on a range of PNH and normal samples, the 5-color assay has significant advantages. Only a single 5-color WBC reagent cocktail is required to detect both PNH granulocytes and monocytes. Additionally, sample preparation and analysis time is reduced yielding significant efficiencies in technical resources and reagent costs. All 4- and 5-color reagent sets stained stabilized whole blood PNH preparations, used in external quality assurance programs.


Subject(s)
Flow Cytometry/methods , Granulocytes/cytology , Hemoglobinuria, Paroxysmal/diagnosis , Monocytes/cytology , Pore Forming Cytotoxic Proteins , ADP-ribosyl Cyclase/analysis , Antigens, CD/analysis , Bacterial Toxins , CD24 Antigen/analysis , Fucosyltransferases/analysis , GPI-Linked Proteins/analysis , Humans , Leukocyte Common Antigens/analysis , Lewis X Antigen/analysis , Lipopolysaccharide Receptors/analysis , Receptors, IgG/analysis
4.
Article in English | MEDLINE | ID: mdl-23893962

ABSTRACT

Background: Recent Flow Cytometric guidelines to detect Paroxysmal Nocturnal Hemoglobinuria (PNH) in white blood cells recommend using FLAER-based assays to detect granulocytes and monocytes lacking expression of GPI-linked structures. However national proficiency testing results continue to suggest a need for improved testing algorithms, including the need to optimize diagnostic analytes in PNH. Methods: CD157 is another GPI-linked structure expressed on both granulocytes and monocytes and here we assess its ability to replace CD24 and CD14 in predicate 4-color granulocyte and monocyte assays respectively. We also assess a single tube, 5-color combination of FLAER, CD157, CD64, CD15 and CD45 to simultaneously detect PNH clones in granulocyte and monocyte lineages. Results: Delineation of PNH from normal phenotypes with 4- or 5-color CD157-based assays compared favorably with 4-color predicate methods and PNH clone size data were similar and highly correlated (R2 >0.99) with predicate values over a range (0.06% - 99.8%) of samples. Both CD157-based assays exhibited similar high levels of sensitivity and low background levels in normal samples. Conclusion: While CD157-based 4- and 5-color assays generated closely similar results to the predicate assays on a range of PNH and normal samples, the 5-color assay has significant advantages. Only a single 5-color WBC reagent cocktail is required to detect both PNH granulocytes and monocytes. Additionally, sample preparation and analysis time is reduced yielding significant efficiencies in technical resources and reagent costs. All 4- and 5-color reagent sets stained stabilized whole blood PNH preparations, used in external quality assurance programs. © 2013 Clinical Cytometry Society.

5.
Int J Lab Hematol ; 35(5): 548-54, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23521723

ABSTRACT

BACKGROUND: Flow cytometric methods (FCMs) are the contemporary standard for fetal red blood cell (RBC) quantitation and fetomaternal hemorrhage (FMH) detection. FCM provides greater sensitivity and repeatability relative to manual microscopic Kleihauer-Betke methods. FCM assays are not totally objective, employing subjective manual gating of fetal RBCs with measureable interobserver imprecision. We investigated Probability State Modeling to automate analysis of fetal RBCs using an assay for hemoglobin F (HbF)-containing RBCs. METHODS: Two hundred human bloods were processed using the FMH QuikQuant™ assay (Trillium Diagnostics, Brewer, ME, USA). A Probability State Model (PSM) was designed to enumerate fetal RBCs by selecting the three RBCs subpopulation based on differences in intensity levels of several parameters. The GemStone™ program uses a PSM that requires no operator intervention. Routine manual analysis by experienced users was performed, along with replicate analyses for both methods. RESULTS: The PSM by GemStone™ correlates strongly with the expert manual analysis, r(2) = 0.9986. The mean absolute difference of the FMH results between GemStone™ and manual 'expert' analysis was 0.04% with no intermethod bias detected. Manual gating demonstrated coefficient of variations (CVs) of 10.6% for intra-analyst replicates and 22.6% for interanalyst imprecision. The interanalyst agreement in GemStone™ is a perfect correlation, r(2) = 1.00, and no imprecision with a 0.00% CV. CONCLUSION: Automated PSM analysis of fetal RBCs strongly correlates with expert traditional manual analysis. PSM enumerates fetal RBCs accurately with significantly greater objectivity and lower imprecision than the traditional manual gating method. Thus, PSM provides a means to markedly improve interlaboratory variance with FMH assays based upon subjective gating strategies.


Subject(s)
Erythrocytes/metabolism , Fetal Blood/cytology , Fetal Hemoglobin/metabolism , Fetomaternal Transfusion/diagnosis , Flow Cytometry/methods , Models, Statistical , Female , Humans , Pregnancy , Probability , Reproducibility of Results
6.
Cytometry B Clin Cytom ; 72 Suppl 1: S5-13, 2007.
Article in English | MEDLINE | ID: mdl-17803188

ABSTRACT

The clinical indications for diagnostic flow cytometry studies are an evolving consensus, as the knowledge of antigenic definition of hematolymphoid malignancies and the prognostic significance of antigen expression evolves. Additionally the standard of care is not routinely communicated to practicing clinicians and diagnostic services, especially as may relate to new technologies. Accordingly there is often uncertainty on the part of clinicians, payers of medical services, diagnostic physicians and scientists as to the appropriate use of diagnostic flow cytometry. In an attempt to communicate contemporary diagnostic utility of immunophenotypic flow cytometry in the diagnosis and follow-up of patients with hematolymphoid malignancies, the Clinical Cytometry Society organized a two day meeting of international experts in this area to reach a consensus as to this diagnostic tool. This report summarizes the appropriate use of diagnostic flow cytometry as determined by unanimous approval of these experienced practitioners.


Subject(s)
Flow Cytometry/methods , Hematologic Neoplasms/diagnosis , Hematologic Neoplasms/metabolism , Immunophenotyping/methods , Hematologic Neoplasms/pathology , Humans , Paraproteinemias/pathology
7.
J Evol Biol ; 20(5): 1772-82, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17714295

ABSTRACT

The evolution of resource sharing requires that the fitness benefits to the recipients be much higher than the costs to the giver, which requires heterogeneity among individuals in the fitness value of acquiring additional resources. We develop four models of the evolution of resource sharing by either direct or indirect reciprocity, with equal or unequal partners. Evolution of resource sharing by reciprocity requires differences between interacting individuals in the fitness value of the resource, and these differences must reverse although previous acts of giving are remembered and both participants survive. Moreover, inequality in the expected reproductive value of the interacting individuals makes reciprocity more difficult to evolve, but may still allow evolution of sharing by kin selection. These constraints suggest that resource sharing should evolve much more frequently by kin selection than by reciprocity, a prediction that is well supported by observations in the natural world.


Subject(s)
Altruism , Behavior, Animal , Biological Evolution , Animals , Models, Theoretical
8.
Handb Exp Pharmacol ; (180): 117-65, 2007.
Article in English | MEDLINE | ID: mdl-17554507

ABSTRACT

An increasing number of patients living with cardiovascular disease (CVD) and still unacceptably high mortality created an urgent need to effectively treat and prevent disease-related events. Within the past 5 years, skeletal myoblasts (SKMBs) and bone marrow (or blood)-derived mononuclear cells (BMNCs) have demonstrated preclinical efficacy in reducing ischemia and salvaging already injured myocardium, and in preventing left ventricular (LV) remodeling, respectively. These findings have been translated into clinical trials, so far totaling over 200 patients for SKMBs and over 800 patients for BMNCs. These safety/feasibility and early phase II studies showed promising but somewhat conflicting symptomatic and functional improvements, and some safety concerns have arisen. However, the patient population, cell type, dose, time and mode of delivery, and outcome measures differed, making comparisons problematic. In addition, the mechanisms through which cells engraft and deliver their beneficial effects remain to be fully elucidated. It is now time to critically evaluate progress made and challenges encountered in order to select not only the most suitable cells for cardiac repair but also to define appropriate patient populations and outcome measures. Reiterations between bench and bedside will increase the likelihood of cell therapy success, reduce the time to development of combined of drug- and cell-based disease management algorithms, and offer these therapies to patients to achieve a greater reduction of symptoms and allow for a sustained improvement of quality of life.


Subject(s)
Bone Marrow Cells/cytology , Cardiomyoplasty , Heart Failure/therapy , Myoblasts, Skeletal/transplantation , Myocardial Infarction/therapy , Stem Cell Transplantation/methods , Animals , Arrhythmias, Cardiac/etiology , Bone Marrow Transplantation , Clinical Trials as Topic , Hematopoietic Stem Cell Transplantation , Humans , Research Design , Transplantation, Autologous
9.
Clin Lab Haematol ; 23(3): 149-54, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11553054

ABSTRACT

Level of foetal haemoglobin (HbF) containing red cells (F cells) is a parameter for monitoring sickle cell anaemia (SS) patients undergoing treatment with HbF modulating drugs (including hydroxyurea (HU)). One convenient technique for F cell assay is flow cytometry. A flow cytometric method for the simultaneous assay of F cells, reticulocytes and HbF-containing reticulocytes (F reticulocytes) is described in this paper. These three parameters can be obtained within 2 h using double colour staining flow cytometry. Glutaraldehyde fixation, Triton X-100 permeabilization, monoclonal antibody to HbF Tri-colour conjugate (MoAb-HbF-TC; deep-red fluorescence) immuno-staining and thiazole orange (TO; green fluorescence) are employed. The red cell gate was set on forward scatter (FSC) and logarithmic side scatter (logSSC) for 50 000 cells on the flow cytometer. Fluorescent signals were acquired from fluorescent channel 1 (FL1; green) and (FL4; deep-red). Coefficient of variation percent (%CVs) of intra- and inter-assay were less than 9% and 15%, respectively. EDTA, citrate, heparin and CTAD anticoagulants are all suitable; the samples can be stored at 4 degrees C for up to 6 days. The method is a simple, rapid, convenient, reproducible and useful way of determining F cell, reticulocyte and F reticulocyte levels in sickle cell and thalassaemic patients.


Subject(s)
Erythrocytes/chemistry , Fetal Hemoglobin/analysis , Flow Cytometry/methods , Reticulocytes/chemistry , Anemia, Sickle Cell/blood , Anemia, Sickle Cell/drug therapy , Anticoagulants/pharmacology , Erythrocyte Indices , Humans , Hydroxyurea/pharmacology , Hydroxyurea/therapeutic use , Reproducibility of Results , Reticulocytes/cytology , Thalassemia/blood
10.
Clin Exp Immunol ; 125(2): 258-65, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11529918

ABSTRACT

Evidence is growing to suggest that the multiple organ damage of the systemic inflammatory response syndrome (SIRS) arises from the untoward activity of blood polymorphonuclear cells (PMNs), which upon activation acquire the IgG high affinity receptor, CD64. In the current study, flow cytometry was used to assess the prevalence of CD64-bearing PMNs and the intensity of expression of CD64 in whole blood samples from 32 SIRS patients, 11 healthy normal subjects and from eight non-SIRS patients in the intensive care unit (ICU). The percentage of PMNs expressing CD64 was higher in SIRS patients (mean 65%) than in non-SIRS patients (mean 42%; P < 0.02) and in healthy controls (mean 19%; P < 0.001) and was particularly evident in patients with SIRS and sepsis (mean 71%; P < 0.02) as opposed to SIRS alone (mean 55%). There were more CD64 molecules expressed on PMNs from patients with SIRS (median 1331 molecules/cell) in comparison with PMNs from healthy subjects (median 678 molecules/cell; P < 0.01). The highest intensity of CD64 expression was associated with PMNs from patients with both SIRS and sepsis. Functional studies revealed that the supranormal binding of PMNs from patients with SIRS to endothelial monolayers treated with TNFalpha was impeded by anti-CD64 antibodies (mean 24% inhibition; P < 0.01). Monitoring the distribution of CD64+ PMNs and their level of CD64 expression could be of assistance in the rapid discrimination of patients with SIRS from other ICU patients and in the identification of PMNs which are likely to participate in the pathological manifestations of the disease.


Subject(s)
Neutrophils/immunology , Receptors, IgG/biosynthesis , Systemic Inflammatory Response Syndrome/immunology , Adult , Aged , Antibodies/immunology , Cell Adhesion , Endothelium, Vascular/immunology , Flow Cytometry , Humans , Middle Aged , Receptors, IgG/immunology
11.
Am J Clin Pathol ; 116(1): 41-50, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11447750

ABSTRACT

We describe 2 male patients in whom hepatosplenic gamma/delta T-cell lymphoma (HSTL) developed 6 and 10 years after renal transplantation. The onset was abrupt with systemic symptoms, cytopenia, and hepatosplenomegaly. The histologic examination of the spleen (case 1), liver, and bone marrow revealed sinusoidal infiltrates of markedly abnormal lymphocytes. The neoplastic cells in these cases were CD2+, CD3+, CD4-, CD5-, CD7+, CD8+, CD16+, CD56+, beta F1-negative, and TIA-1-negative. Both cases displayed clonal rearrangement of the T-cell receptor (TCR) delta gene and the TCR beta gene. The spleen in case 1 was positive for Epstein-Barr virus genome and showed TCR-gamma gene rearrangement by polymerase chain reaction. Isochromosome 7 [i(7)(q10)] was found in each case. Both patients died within 4 months of diagnosis. HSTL has been reported in only 5 renal transplant recipients. HSTL may be relatively more frequent in immunocompromised patients compared with the general population.


Subject(s)
Immunocompromised Host , Liver Neoplasms/genetics , Liver Neoplasms/immunology , Receptors, Antigen, T-Cell, gamma-delta/genetics , Splenic Neoplasms/genetics , Splenic Neoplasms/immunology , Adult , Bone Marrow/metabolism , Bone Marrow/pathology , Cytogenetic Analysis , Humans , Immunophenotyping , Immunosuppression Therapy/adverse effects , Kidney Transplantation , Liver Neoplasms/etiology , Liver Neoplasms/pathology , Male , Middle Aged , Splenic Neoplasms/etiology , Splenic Neoplasms/pathology
13.
Semin Hematol ; 38(2): 148-59, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11309696

ABSTRACT

The majority of clinical applications of flow cytometry begin with various approaches to remove red blood cells (RBCs) from the clinical sample. However, multiparameter cytometry has and will continue to contribute much to the understanding of the pathophysiology and diagnostic accuracy in the clinical evaluation of human diseases affecting erythroid cells. This review summarizes the diagnostic advances relating to erythroid cells in the areas of immunohematology, laboratory hematology, and infectious disease with particular emphasis on medical evaluation of the anemic patient and fetomaternal hemorrhage. Semin Hematol 38:148-159.


Subject(s)
Erythrocytes, Abnormal , Erythropoiesis/immunology , Hematologic Diseases/diagnosis , Animals , Erythrocytes, Abnormal/immunology , Erythrocytes, Abnormal/microbiology , Flow Cytometry/methods , Humans , Immunophenotyping/methods
14.
Cytometry ; 46(1): 23-7, 2001 Feb 15.
Article in English | MEDLINE | ID: mdl-11241503

ABSTRACT

At the ISAC 2000 Congress, the Clinical Cytometry Society organized a meeting of international experts to reach consensus on the minimum number of antibodies required for a full evaluation of hematologic and lymphoid neoplasias. A questionnaire was distributed prior to the meeting to numerous experts from US and European institutions and 13 responses were received. At the meeting, 25 individuals, including most of those who returned responses, participated in the discussions and voted on the issues presented. In chronic lymphoproliferative disorders (CLD), 9 antibodies (anti-CD5, CD19, kappa, lambda, CD3, CD20, CD23, CD10, and CD45) were deemed essential for initial evaluation by 75% of the participants. There was near unanimity that additional markers (selected from CD22, FMC7, CD11c, CD103, CD38, CD25, CD79b and heavy chains for B-cell disorders, and CD4, CD7, CD8, CD2, CD56, CD16, TCRa/b, and TCRg/d for T-cell disorders) would be needed to fully characterize CLD, although not every marker would be useful in all cases. Tissue lymphomas were believed to be similar to CLD, needing a minimum of 12--16 markers. However, for some cases, CD30, bcl-2, TdT, CD71, CD1a, and CD34 were cited as useful by the participants. Markers mentioned for plasma cell disorders included kappa, lambda, CD38, CD45, CD56, CD19, CD20, CD138, and heavy chains. Of 17 voting participants, 16 agreed that between 5 to 8 markers would be essential reagents for plasma cell disorders. For acute leukemia (AL), 10 markers (CD10, CD19, CD13, CD33, CD34, CD45, CD7, CD14, CD3, and HLADR) were considered essential by 75% of participants for initial characterization of the leukemia lineage. Most (>75%) agreed that at least one more B (CD20, CD22, CD79a, IgM), T (CD1a, CD2, CD4, CD5, CD8), myeloid (CD11b, CD15, CD64, CD117, myeloperoxidase), erythroid (CD36, CD71, glycophorin A), and megakaryocytic (CD41, CD61) reagents should be included in the essential panel. However, there was no agreement as to which was optimal. Thus, approximately 13--15 of those reagents would be considered essential in all cases of AL, whereas others (CD16, CD56, CDw65, TdT, and cytoplasmic CD3) were mentioned as useful in some cases. Almost all voting participants believed that the appropriate number of markers for complete characterization of AL would average 20--24. The majority of the responders (11 of 13) indicated that fewer reagents could be used in monitoring or staging patients with previously characterized disease, but not all ventured a specific number of reagents. From the above results, we conclude that the phenotypic analysis of hematologic and lymphoid neoplasia requires a rather extensive panel of reagents. Supplementary reagents might even be necessary if they prove to become relevant for diagnostic purposes. Reducing the number of antibodies could significantly compromise the diagnostic accuracy, appropriate monitoring, or therapy of these disorders.


Subject(s)
Biomarkers , Hematologic Neoplasms/diagnosis , Immunophenotyping/standards , Lymphoma/diagnosis , Biomarkers/analysis , Flow Cytometry , Hematologic Neoplasms/immunology , Humans , Leukemia/diagnosis , Leukemia/immunology , Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis , Leukemia, Lymphocytic, Chronic, B-Cell/immunology , Lymphoma/immunology , Plasmacytoma/diagnosis , Plasmacytoma/immunology , Surveys and Questionnaires
15.
Am J Clin Pathol ; 115(2): 258-65, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11211615

ABSTRACT

CD23 and FMC-7 are normal B-cell antigens used during diagnostic immunophenotyping of suspected lymphoproliferative disorders, but the diagnostic usefulness of antigenic expression patterns of simultaneous 2-color staining and flow cytometric analysis has not been reported. We evaluated the FMC-7 and CD23 expression pattern in 201 cases of B-cell lymphoma from tissue biopsy specimens by multiparameter flow cytometry. The CD23-/FMC-7+ pattern was the most common pattern in large cell, mantle cell, and marginal zone lymphomas. The CD23 and FMC-7 antigen, along with the CD5 coexpression pattern, permitted accurate classification of all 71 cases of small lymphocytic, mantle cell, and marginal zone types of lymphoma. The widest variation of patterns was with follicular cell lymphoma, although most cases expressed the CD23 +/-/FMC-7+ pattern (+/-, partial or minor subset expression). The CD23 and FMC-7 antigen expression pattern was predictive of subtypes in more than 95% of lymphoma cases and could narrow the differential diagnosis in the remaining cases. We conclude the flow cytometric CD23/FMC-7 expression pattern achieved by dual staining facilitates accurate and reproducible classification of B-cell lymphomas and has diagnostic usefulness.


Subject(s)
Antigens, Neoplasm/metabolism , Glycoproteins/metabolism , Lymphoma, B-Cell/classification , Receptors, IgE/metabolism , Algorithms , Biopsy , CD5 Antigens/metabolism , Flow Cytometry , Humans , Lymph Nodes/pathology , Lymphoma, B-Cell/diagnosis , Lymphoma, B-Cell/metabolism , Precursor Cell Lymphoblastic Leukemia-Lymphoma/classification , Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolism
16.
Clin Lab Med ; 21(4): 829-40, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11770290

ABSTRACT

Although most of the diagnostic applications of flow cytometry bring forth examples of leukocyte immunophenotyping for immunodeficiency diseases and leukemia-lymphoma diagnosis, the same technology has improved medical assessment of diseases affecting the red cell and erythropoiesis. Flow cytometric methods were first applied to laboratory hematology with the improvement in reticulocyte counting and the creation of the immature reticulocyte fraction for better anemia evaluation and therapeutic monitoring. A more recent improvement attributable to flow cytometry is accurate detection of fetal red cells in the evaluation of FMH hemorrhage. The same method used in the detection of fetal RBCs based on HbF content measurement using monoclonal antibodies also offers the potential for enumeration of F cells, which promises to have use in therapeutic monitoring of patients with sickle cell disease and the evaluation of other hemoglobinopathies and myelodysplasia. Other clinical uses of flow cytometric RBC analysis include nonisotopic red cell survival studies, sensitive blood group typing, sensitive detection of immune-mediated hemolytic diseases, and evaluation of parasitic diseases whose life cycle involves intracellular RBC infestation. This article summarizes red cell flow cytometry, particularly as it impacts the areas of immunohematology and laboratory hematology, and points to areas of potential future contribution of this technology to diagnostic medicine.


Subject(s)
Erythrocytes, Abnormal/pathology , Flow Cytometry/methods , Hematologic Diseases/diagnosis , Adult , Antigens, Surface/analysis , Erythrocytes, Abnormal/chemistry , Erythropoiesis/physiology , Female , Fetomaternal Transfusion/diagnosis , Flow Cytometry/instrumentation , Flow Cytometry/trends , Hemoglobins/analysis , Humans , Pregnancy , Reproducibility of Results , Sensitivity and Specificity
17.
Hematology ; 6(1): 91-100, 2001.
Article in English | MEDLINE | ID: mdl-27419609

ABSTRACT

Red blood cells (RBCs) from sickle cell patients (SS) express thrombospondin receptor (CD36), contain ribonucleic acid (RNA, recognised as reticulocytes) and fetal haemoglobin (HbF, defined as F cells) in a higher proportion than RBCs from healthy individuals. The co-distribution of CD36, RNA and HbF on the same RBCs has not been demonstrated due to a lack of detection methods. A triple-colour staining flow cytometry for the co-distribution of CD36, RNA and HbF was developed. The method can simultaneously determine CD36-expressing RBCs (CD36 cells), RNA-bearing RBCs (reticulocytes), HbF-bearing RBCs (F cells), CD36-expressing reticulocytes (CD36 reticulocytes), CD36-expressing-F cells (CD36-F cells), HbF-bearing reticulocytes (F reticulocytes) and CD36-expressing-F reticulocjrtes (CD36-F reticulocytes). Mouse monoclonal antibody against CD36 (MoAb-CD36), antibodagainst mouse-immunoglobulin conjugated to biotin (Ab-Molg-Bi), streptavidin conjugated to rhodamine phycoerythrin (StA-RFE), MoAb against HbF conjugated to Tri-Colour® (MoAb-HbF-TC), Thiazole orange (TO), Glutaraldehyde and Triton X-100 were used. The procedure takes approximately 7 hours. The numbers of CD36 cells, reticulocytes and F cells obtaining from single and triple staining were well correlated and not significantly different. Intra- and inter-assay coefficient of variation percents (%CVs) of the triple-colour staining were less than 10 and 15% respectively. EDTA blood samples stored at 4°C for less than 3 days are suitable. The method trial was then employed on blood samples from SS and healthy individuals. The method is reproducible, objective and applicable for determination of co-distribution of other membrane and intracellular markers in RBCs.

18.
Cytometry ; 42(4): 239-46, 2000 Aug 15.
Article in English | MEDLINE | ID: mdl-10934343

ABSTRACT

BACKGROUND: Quantitation of adult erythrocytes (RBC) containing fetal hemoglobin (F cells) is of potential clinical utility in evaluating erythropoietic disorders, such as myelodysplasia and hemoglobinopathies, and in monitoring F-cell augmenting therapy. F-cell counting methodologies include fluorescence microscopy and flow cytometry. Previous flow cytometric methods have employed an isotype antibody control to distinguish F cells from non-F cells. We investigated the feasibility of using the orange autofluorescence signal (FL2) in glutaraldehyde-fixed RBC to substitute for fluorescein isothiocyanate (FITC)-labeled isotype control antibody use in F-cell quantitation. METHODS: Our previously published method for fetal red cell detection in fetomaternal hemorrhage was used, employing a FITC-labeled anti-hemoglobin F (HbF) monoclonal antibody reagent. Blood samples with varying F-cell counts were quantitated for F cells using both immunofluorescence microscopy and flow cytometry comparing FITC-labeled isotype to FL1 thresholding defined by FL2 autofluorescence. RESULTS: F cell percentages obtained by using an FL2 defined threshold for FL1 gating correlated well with expected values in diluted blood samples (r(2) = 0.994, slope = 1. 019, intercept = 0.24), values obtained using an isotype control (r(2) = 0.996, slope = 1.012, intercept = -0.17), and microscopic immunofluorescence counts (r(2) = 0.989, slope = 0.999, intercept = -0.72). F-cell quantitation by the isotype control and FL2 autofluorescence methods was also comparable in 40 blood samples (r(2) = 0.994, slope = 1.014, intercept = 0.03). Intra-assay, interobserver, and interinstrument precision with this autofluorescence gating method exhibited low imprecision (coefficient of variation <14%). CONCLUSION: This novel method is a more objective and less laborious alternative for F-cell quantitation by flow cytometry compared to using an isotype control or microscopy, thereby providing a more robust methodology for clinical studies and consideration as a laboratory reference method for F-cell counting.


Subject(s)
Erythrocyte Count/methods , Erythrocytes/metabolism , Fetal Hemoglobin/metabolism , Flow Cytometry/methods , Adult , Evaluation Studies as Topic , Female , Fetomaternal Transfusion/blood , Fetomaternal Transfusion/diagnosis , Flow Cytometry/standards , Fluorescein-5-isothiocyanate , Fluorescent Dyes , Humans , Microscopy, Fluorescence , Pregnancy , Quality Control
19.
Leuk Res ; 24(5): 417-26, 2000 May.
Article in English | MEDLINE | ID: mdl-10785264

ABSTRACT

The outcome of patients diagnosed myelodysplastic syndromes (MDS) between 1990 and 1997 from William Beaumont Hospital (WBH) was analyzed according to the International Prognostic Scoring System (IPSS) risk categorization. A retrospective study of 195 MDS patients wa s performed. Seventy-nine patients with MDS, in whom a karyotype was obtained and with an adequate follow-up were included in the final analysis. Cases of proliferative CMML (WBC > 12x10(9)/l) were excluded from the study. The overall median survival was 3.1 years, and median survival stratified by IPSS was 3.4, 4.1 and 0.5 years for the INT-1, INT-2 and high risk group and not yet reached for the low risk group. The overall survival by IPSS subcategorization were 6.88, 5.29, 5.30 and 2.12 years for the low, INT-1, INT-2, and high risk groups respectively. Cytogenetics were significant in predicting the overall survival. The IPSS score stratified patients into risk categories for development of AML. The risk of development into AML was 8, 8, 33 and 54% for the low, INT-1, INT-2 and high risk groups, respectively. We conclude that IPSS score can be useful in predicting survival and AML evolution in some MDS patients.


Subject(s)
Myelodysplastic Syndromes/physiopathology , Acute Disease , Aged , Female , Hospitals, Community , Humans , Leukemia, Myeloid/etiology , Male , Middle Aged , Myelodysplastic Syndromes/complications , Myelodysplastic Syndromes/mortality , Prognosis , Retrospective Studies , Risk , Survival Analysis
20.
Mol Cell Biol ; 20(8): 2818-26, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10733585

ABSTRACT

Alcohol-induced cirrhosis results partially from the excessive production of collagen matrix proteins, which, predominantly alphaI(I) collagen, are produced and secreted by activated hepatic stellate cells (HSC). The accumulation of alphaI(I) collagen in HSC during cirrhosis is largely due to an increase in alphaI(I) collagen gene expression. Acetaldehyde, the major active metabolite of alcohol, is known to stimulate alphaI(I) collagen production in HSC. However, the mechanisms responsible for it remain unknown. The aim of this study was to elucidate the mechanisms by which alphaI(I) collagen gene expression is induced by acetaldehyde in rat HSC. In the present study, the acetaldehyde response element was located in a distal GC box, previously described as the UV response element, in the promoter of the alphaI(I) collagen gene (-1484 to -1476). The GC box was predominantly bound by the DNA binding transcription factor BTEB (basic transcription element binding protein), expression of which was acetaldehyde and UV inducible. Blocking BTEB protein expression significantly reduced the steady-state levels of the acetaldehyde-induced alphaI(I) collagen mRNA, suggesting that BTEB is required for this gene expression. Further studies found that acetaldehyde activated Jun N-terminal kinase (JNK) 1 and 2 and activator protein 1 (AP-1) transactivating activity. Inhibition of JNK activation resulted in the reduction of the acetaldehyde-induced BTEB protein abundance and alphaI(I) collagen mRNA levels, indicating that the expression of both genes is JNK dependent in HSC. Taken together, these studies demonstrate that BTEB mediates acetaldehyde-induced, JNK-dependent alphaI(I) collagen gene expression in HSC.


Subject(s)
Collagen/biosynthesis , Collagen/genetics , Connective Tissue Cells/physiology , DNA-Binding Proteins/genetics , Gene Expression Regulation , Mitogen-Activated Protein Kinases/genetics , Transcription Factors/genetics , Acetaldehyde/pharmacology , Animals , DNA-Binding Proteins/metabolism , Gene Expression Regulation/drug effects , JNK Mitogen-Activated Protein Kinases , Kruppel-Like Transcription Factors , Liver , Male , Mitogen-Activated Protein Kinases/metabolism , Rats , Rats, Sprague-Dawley , Signal Transduction/drug effects , Transcription Factors/metabolism , Zinc Fingers
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