摘要:

AbstractWe studied the red cell membrane neutral phosphatase, which is part of the Na+K+ATPase, in several types of oxidative hemolytic anemias. We used an artificial substrate, the p‐nitrophenylphosphate. In controls and in patients heterozygous for various unstable hemoglobins (Hb Hope, Hb Köln, or Hb Hammersmith), the kinetics were of the Michaelis‐Menten type. On the contrary, in nearly all patients with α‐ or β‐thalassemia, the kinetics displayed an abnormally biphasic character. The apparent Michaelis constant (KMapp) was significantly decreased. The biphasic character correlated with the imbalance of globin chain synthesis. The β‐mercaptoethanol markedly increased Vmaxin controls, but had little effect on the biphasic kinetics. Omission of K+abolished the biphasic kinetics. The abnormal kinetics failed to appear with another artificial substrate, the 4‐methylum‐belliferylphosphate, nor did it appear with ATP, the natural substrate. In vitro, H2O2treatment of normal and thalassemic red cells was unable to induce or exaggerate, respectively, the biphasic kinetics, but generated alterations of a different nature. We suggest that the various kinetic alterations of the phosphatase in thalassemic syndromes originate from the imbalance of globin chain synthesis. However, the involvement of an oxidative process remains t

ISSN:0361-8609    

DOI:10.1002/ajh.2830130402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractThe deformability of the erythrocyte (RBC) is greatly influenced by its state of hydration. The purpose of this investigation is to quantitate this relationship by measuring the deformability of an RBC population over a broad range of cell water content. By manipulation of the ion content of the RBC, we performed all of the experiments in media which were isotonic with plasma. To raise ion and water content, RBC were incubated in a Li2CO3medium. To lower cell ion and water content, RBC were exposed to the K ionophore, valinomycin. The range of cell water content achieved during the entire experiment was 900–3200 g/kg cell solid (normal in vivo cell water content being 1800–1950 g/kg cell solid). By using the Ektacytometer, an automated cylindrical viscometer, we were able to measure deformability of the RBC sampled at various points along this range of cell water content. We found that optimal rheologic behavior was exhibited by normal RBC when their water content was in the normal range. A rise or a fall in cell hydration resulted in a decrease in cell deformability. By contrast, the deformability of freshly drawn, well‐oxygenated sickle RBC was well below that found for normal RBC. Upon volume expansion, however, the deformability of these sickle RBC improved markedly. This observation suggests that sickle RBC are suboptimally hydrated and that their abnormal rheology is at least in part a consequence of cell dehydr

ISSN:0361-8609    

DOI:10.1002/ajh.2830130403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractFive members of a new family with hemoglobin Osler are described. Exercise studies were performed before and after phlebotomy in one patient. These studies demonstrated that anaerobic threshold was directly related to hematocrit. Our data suggest that the elevation of red cell mass seen with this high oxygen affinity hemoglobin is an appropriate physiologic response which improves tissue oxygen delivery. Despite the increase in whole blood viscosity associated with erythrocytosis, our data do not support the use of therapeutic phlebotomy to improve exercise performance in patients with hemoglobin Osler.

ISSN:0361-8609    

DOI:10.1002/ajh.2830130404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractNeutrophil engulfment by megakaryocytes was observed within 20 to 30% of megakaryocytes from two children: one with metastatic rhabdomyosarcoma, the other with fever of unknown origin. Other cell types and neutrophil precursors were not observed within megakaryocytes. Only late megakaryocytes were involved in the process, and often these cells appeared vacuolated or degenerating at the light and electron microscope level. Ultrastructurally the engulfed neutrophils were intact and were within the open canalicular system of the megakaryocyte cytoplasm. No evidence of neutrophil granule exocytosis could be demonstrated in ultrastructural morphologic and peroxidase preparations; however, many neutrophils appeared to be endocytosing portions of the megakaryocyte cytoplasm. The phenomenon could not be transferred to normal marrow incubated with patient serum or plasma. Thus, our patients differ from previous observations of emperipolesis in: 1) the extreme frequency of the observation; 2) the selective involvement of neutrophils; and 3) the association of the anomaly with dysmorphic and/or disrupted megakaryocytes. These observations are consistent with a neutrophil response to altered and/or injured megakaryocytes.

ISSN:0361-8609    

DOI:10.1002/ajh.2830130405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractThe clinical features and disease course of 29 consecutive multiple myeloma patients without monoclonal globulins are described. This variant accounted for 4.7% of all patients with this disease referred over a 17 year time span. Despite bone marrow plasmacytosis and multiple bone lesions in all, hemoglobin levels were less frequently depressed and immunoglobulin values more frequently preserved in comparison with typical myeloma patients. A low tumor mass was defined in 69%, in comparison with 24% of those with evidence of myeloma protein production. Such earlier disease contributed to the long median survival of 39 months in these patients, a duration about 1 year longer than that of typical patients.

ISSN:0361-8609    

DOI:10.1002/ajh.2830130406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractHemoglobin H (HbH) disease was recently described in three unrelated northern European boys with mental retardation. We have studied a somewhat similar patient, in whom HbH disease was associated with multiple congenital anomalies. Restriction endonuclease analysis of DNA from this proband yielded a pattern consistent with the α‐/– genotype commonly associated with the HbH phenotype in Asians. His parents both carry α thalassemia, in contrast to the previously described families in which only one of the two parents was a ca

ISSN:0361-8609    

DOI:10.1002/ajh.2830130407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractHemoglobin Queens: α34 (B15) Leu‐Arg was found in association with Hb E in a Vietnamese boy. The observed microcytosis and hypochromia were due to Hb E, which also occurred in other members of this family. The functional properties of Hb Queens in the absence and presence of allosteric effectors were normal. The abnormal hemoglobins appear to be unrelated to the hyperbilirubinemia that was observed at bir

ISSN:0361-8609    

DOI:10.1002/ajh.2830130408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractIn recent years, chromosomal aberrations in various hematologic disorders have raised a great deal of interest. In fact, several nonrandom chromosomal abnormalities are now recognized to be responsible for a specific type of dyshemopoiesis while others are closely associated with characteristic hematologic features. Monosomy C, later shown to be monosomy 7 by different banding methods, has been described in children in relation to a peculiar myeloproliferative disorder. Retrospective analysis of early cases published in the literature and a recent observation that we wish to report suggest that the most consistent phenotypic expression of monosomy 7 is an increased susceptibility to bacterial infections related to a preleukemic dyshemopoiesis. Acute nonlymphocytic leukemia is the terminal event of this peculiar preleukemic syndrome, and thus suggests that monosomy 7 involves a stem cell already committed to myeloid differentiation.

ISSN:0361-8609    

DOI:10.1002/ajh.2830130409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractThere is much evidence to indicate that inhibitors to Factor VIII in patients with classical hemophilia are the result of an immunological response to exposure to material (VIII:C or VIII:CAg) that is absent or present in reduced amounts in these patients. The inhibitor is an antibody that is usually restricted in immunochemical composition and in many instances contains predominantly or exclusively γG3 or γG4 heavy chains. Exposure to Factor VIII in many inhibitor patients leads to typical anamnestic responses with marked increases in the level of the inhibitor. The tendency to develop inhibitors and the clinical characteristics of the inhibitor may be affected by genetic factors, basal levels of Factor VIII:C and/or VIII:CAg, and the nature and amount of the “immunizing” material. Currently accepted therapeutic modalities are aimed primarily at the management of acute bleeding epi

ISSN:0361-8609    

DOI:10.1002/ajh.2830130410

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractRecently, much attention has been focused on various enzyme alterations found in leukemic cells. Most of the data generated thus far has involved the study of terminal deoxynucleotidyl transferase, the purine pathway enzymes, and hexosaminidase and other lysosomal enzymes. Differences in both total enzyme activities and isoenzyme patterns have been found to occur among the various leukemia types and subtypes. These changes may prove to be useful aids in diagnosing, classifying, detecting subclinical recurrent or residual disease, and as therapeutic determinants in hematopoietic neoplasia, especially in the lymphoid malignancies.

ISSN:0361-8609    

DOI:10.1002/ajh.2830130411

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY