Immunologic status of hemophilia patients treated with cryoprecipitate or lyophilized concentrate

We evaluated 37 patients with moderate or severe hemophilia A and six patients with severe factor IX deficiency for clinical or laboratory evidence of immune abnormalities. Patients were assigned to one of four groups according to the type of clotting factor replacement. Twenty patients had received only cryoprecipitate during the two years preceding the evaluation (group I); 11 additional patients were treated predominantly with cryoprecipitate but had also received up to nine bottles of factor VIII concentrate (group II); six patients received factor VIII concentrate (group III); six patients received factor IX concentrate (group IV). There was no clinical or laboratory evidence of immunodeficiency among the 43 patients. The mean absolute number of Th cells was normal in all patient groups, but the mean absolute number of Ts cells was increased compared with controls, both in patients treated with cryoprecipitate and in patients treated with factor VIII or factor IX concentrate. There was no correlation between the Th/Ts ratio and patient age, alanine aminotransferase level, hepatitis serology, in vitro lymphocyte function, or amount of clotting factor administered. Our observations demonstrate that the volunteer or commercial origin of clotting factor replacement cannot fully explain the alterations in lymphocyte subset distribution previously described in patients with hemophilia A.     

A statistical analysis of murine stem cell suicide techniques

The clinical application of soft agar cloning techniques for granulocyte-macrophage stem cells (CFU-C) has resulted in a number of contradictory reports that may in part be due to an inadequate data base. Growth of murine CFU-C is more reproducible and less variable than that of human CFU-C. We utilized in vivo hydroxyurea suicide of murine marrow CFU-C to address the question of how many experiments are needed to detect a specific difference with a p of less than 0.05. In 66 experiments the mean marrow CFU-C hydroxyurea kill was 23.3%; 6-9 separate experiments were necessary to detaect differences of 25%-30%. In order to be sure that a 25%-30% difference is not present, 15-21 experiments were required. Using a Dec-20 computer, 1000 samples of sample size 3, 4, or 10 were drawn from the 66 experiments; it was found that with 3 experiments and a true value of 23%, the actually observed value was below 10%, 17% of the time, and was over 40% in 10% of the samplings. In a smaller number of experiments similar results were obtained analyzing 3HTdR suicide of pluripotent stem cells and CFU- C. These data could provide a base from which to judge the validity of studies utilizing the CFU-C technique.     

小唾液腺癌治疗新进展

该文旨在对小唾液腺癌的治疗进行回顾。小唾液腺癌可发生在头颈部很多位置,通常表现为黏膜下肿块。影像学检查是对肿瘤发病部位及病变范围内解剖结构的关系进行评估的基础。切取活检或穿吸活检可以决定肿瘤的病理类型和分级。随着分子生物学技术的不断进步,小唾液腺癌的诊断     

Higher order aberrations,refractive error development and myopia control: a review

Evidence from animal and human studies suggests that ocular growth is influenced by visual experience. Reduced retinal image quality and imposed optical defocus result in predictable changes in axial eye growth. Higher order aberrations are optical imperfections of the eye that alter retinal image quality despite optimal correction of spherical defocus and astigmatism. Since higher order aberrations reduce retinal image quality and produce variations in optical vergence across the entrance pupil of the eye, they may provide optical signals that contribute to the regulation and modulation of eye growth and refractive error development. The magnitude and type of higher order aberrations vary with age, refractive error, and during near work and accommodation. Furthermore, distinctive changes in higher order aberrations occur with various myopia control treatments, including atropine, near addition spectacle lenses, orthokeratology and soft multifocal and dual-focus contact lenses. Several plausible mechanisms have been proposed by which higher order aberrations may influence axial eye growth, the development of refractive error, and the treatment effect of myopia control interventions. Future studies of higher order aberrations, particularly during childhood, accommodation, and treatment with myopia control interventions are required to further our understanding of their potential role in refractive error development and eye growth.     

"Stem cell" origin of the hematopoietic defect in dyskeratosis congenita

We have used the long-term bone marrow culture (LTBMC) system to analyze hematopoiesis in three patients with dyskeratosis congenita (DC), two of whom had aplastic anemia, and the third had a normal blood count (apart from mild macrocytosis) and normal BM cellularity. Hematopoiesis was severely defective in all three patients, as measured by a low incidence of colony-forming cells and a low level of hematopoiesis in LTBMC. The function of the marrow stroma was normal in its ability to support the growth of hematopoietic progenitors from normal marrows seeded onto them in all three cases, but the generation of hematopoietic progenitors from patients marrow cells inoculated onto normal stromas was reduced, thus suggesting the defect to be of stem cell origin. The parents and unaffected brother of one of the families have also been studied in LTBMC and all showed normal hematopoietic and stromal cell function. From this study we speculate that there are some similarities between DC and the defect in the W/Wv mouse.     

Plasma levels of plasminogen activator inhibitor type 1, beta- thromboglobulin, and fibrinopeptide A before, during, and after treatment of acute myocardial infarction with alteplase

Plasma levels of plasminogen activator inhibitor type-1 (PAI-1), beta- thromboglobulin (beta TG), and fibrinopeptide A (FPA) were followed over 24 hours in 30 patients treated with alteplase for acute myocardial infarction. Samples were taken at baseline (T Oh), after 90 minutes (under alteplase, no heparin, T 1.5h), after 120 minutes (under alteplase and heparin, T 2h), 30 minutes after thrombolytic therapy (T 3.5h), as well as 12 hours (T 12h) and 24 hours (T 24h) after baseline. PAI-1 antigen levels (55 +/- 9 ng/mL at T Oh, mean +/- SEM) decreased to 35 +/- 5 (T 1.5h) and 40 +/- 6 (T 2h) ng/mL under alteplase, before increasing to 84 +/- 22 (T 3.5h), 130 +/- 30 (T 12h), and 64 +/- 7 (T 24h) ng/mL after therapy, P less than .001. A high baseline PAI-1 activity (18 +/- 3 ng/mL) decreased to 2.0 +/- 0.4 (T 1.5h) and 1.7 +/- 0.2 (T 2h) under alteplase and increased to 32 +/- 5 (T 12h) and 19 +/- 3 (T 24h) ng/mL after therapy (P less than .0001). beta TG levels (339 +/- 105 ng/mL at T Oh) decreased to 203 +/- 48 (T 2h), 154 +/- 51 (T 3.5h), 187 +/- 40 (T 12h), and 142 +/- 32 (T 24h) ng/mL under heparin (P less than .01). FPA levels (34 +/- 9 ng/mL at T Oh) increased to 85 +/- 15 ng/mL under alteplase alone (T 1.5h) and normalized under heparin (11 +/- 4, 6 +/- 2, 4 +/- 2, and 3 +/- 1 ng/mL at T 2h, T 3.5h, T 12h, and T 24h, respectively). A high level of FPA at T 3.5h correlated with reocclusion (33 +/- 12 ng/mL, n = 4 v 2.9 +/- 0.5 ng/mL, n = 21, P less than .005). We conclude that plasma levels of PAI- 1 antigen as well as activity markedly increase after alteplase therapy of acute myocardial infarction. The high activity of PAI-1 and decreasing beta TG levels suggest that platelets do not contribute significantly to this phenomenon. The marked increase of FPA levels under recombinant tissue-type plasminogen activator alone and its normalization under heparin emphasize the important role of concomitant anticoagulation in controlling further intravasal fibrin generation under alteplase.     

Heterogeneity of B cell involvement in acute nonlymphocytic leukemia

In order to study the pattern of B cell involvement in acute nonlymphocytic leukemia (ANLL), multiple B lymphoid cell lines were established by Epstein-Barr virus transformation of peripheral blood mononuclear cells from two patients with the disease who were heterozygous for the X chromosome-linked glucose-6-phosphate dehydrogenase (G6PD). In one patient, the progenitor cells involved by the leukemia exhibited multipotent differentiative expression, whereas in the other patient the cells showed differentiative expression restricted to the granulocytic pathway. In the patient whose abnormal clone showed multipotent expression, the ratio of B-A G6PD in B lymphoid cell lines was skewed in the direction of type B (the enzyme characteristic of the leukemia clone) and significantly different from the 1:1 ratio expected. It is, therefore, likely that the neoplastic event occurred in a stem cell common to the lymphoid series as well as to the myeloid series. In contrast, evidence for B cell involvement was not detected in the patient whose ANLL progenitor cells exhibited restricted differentiative expression. These findings underscore the heterogeneity of ANLL. Clinically and morphologically similar malignancies in these two patients originated in progenitors with different patterns of stem cell differentiative expression. This difference may reflect differences in cause and pathogenesis.     

The growth factor requirements of STRO-1-positive human bone marrow stromal precursors under serum-deprived conditions in vitro

Factors that regulate the growth and development of primitive bone marrow stromal cell precursors are not well defined. We have examined 25 purified recombinant growth factors for their ability to initiate and support clonogenic growth of fibroblast colony-forming cells (CFU- F) from adult human bone marrow. Assays were performed using bone marrow mononuclear cells (BMMNC) enriched in CFU-F by magnetic- activated cell sorting (MACS) using the monoclonal antibody (MoAb) STRO- 1. A serum-deprived assay was developed to avoid components of fetal calf serum (FCS) that may mask or otherwise modify the response of CFU- F to exogenously added factors. L-ascorbate and the glucocorticoid dexamethasone were found to be essential for CFU-F colony development under serum-deprived conditions. Importantly, clonogenic growth of CFU- F in this culture system was absolutely dependent on an exogenous source of growth factor. Platelet-derived growth factor-BB (PDGF) and epidermal growth factor (EGF) demonstrated the greatest ability to support colony growth. Colony formation was dose-dependent, with half- maximal colony numbers at approximately 0.2 ng/mL for either factor and plateau numbers at concentrations in excess of 1.0 ng/mL. Simultaneous addition of PDGF and EGF had no effect on the number of colonies initiated but resulted in dose-dependent increases in mean colony diameter that were significant (P < or = .05) when compared with the effect of either factor alone or with the size of colonies elicited in control cultures by 20% FCS. Fluorescence-activated cell sorting (FACS) of BMMNC using MoAbs to the alpha chain of the PDGF receptor and to the EGF receptor in combination with the Moab STRO-1 demonstrated constitutive expression of both receptors by greater than 90% on CFU-F. Receptors for insulin-like growth factor-1 (IGF-1) and nerve growth factor (NGF) were also detected on STRO-1+ CFU-F, but in vitro both IGF- 1 and NGF did not support colony growth. This report demonstrates the development of a simple, reproducible, and stringent culture system for the growth and assay of stromal precursors under serum-deprived conditions and represents an important prerequisite for future studies of the role of growth factors in the regulation of stromal cell proliferation, differentiation, and development.