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591.
Rackoff WR; Orazi A; Robinson CA; Cooper RJ; Alter BP; Freedman MH; Harris RE; Williams DA 《Blood》1996,88(5):1588-1593
This report examines the effect of filgrastim (granulocyte colony- stimulating factor, [G-CSF] in 12 patients with neutropenia [absolute neutrophil count [ANC] < 1,000/mm3]) caused by Fanconi anemia (FA). Two of 14 patients who were evaluated for study entry were ineligible because of unsuspected cytogenetic abnormalities in their bone marrow (BM). G-CSF was started at 5 micrograms/kg/d. All patients had an increase in their ANC at week 8 (mean increase = 15,664/mm3). The median ANC during therapy was 5,030/mm3. Eight of 10 patients who completed 40 weeks on study maintained an ANC > 1,500/mm3 on G-CSF given every-otherday. Four patients had an increase in their platelet count by week 8 without transfusion (maximum increase = 23,000 to 45,000/mm3); however, platelet counts fell toward baseline levels as the G-CSF dose was reduced. BM CFU-MK were increased at week 8 in three of four evaluable patients. Four patients who did not receive red blood cell transfusions had an increase in their hemoglobin level of at least 2.0 g/dL. A fifth patient had a red blood cell transfusion in week 2 and then had a similar increase in hemoglobin level without subsequent transfusion. Eight of 10 patients who completed 40 weeks of treatment showed increases in the percentage of BM CD34+ cells measured by flow cytometry. The same proportion showed increases in peripheral blood CD34+ cells. Increased BM cellularity and myeloid hyperplasia were constant findings and were associated with increased expression of the proliferating cell nuclear antigen. Adverse experiences were mild fever (1 patient) and a new BM cytogenetic abnormality at week 40 (1 patient). This study shows that prolonged administration of G-CSF exerts a stimulatory effect on the BM of FA patients and may be used to maintain a clinically adequate ANC in these patients. G-CSF has beneficial effects on multiple hematopoietic lineages in some patients and may be a good candidate for use in combination cytokine protocols for FA patients with progressive aplastic anemia. G-CSF use results in an increase in circulating CD34+ cells, a finding with important implications for future gene transfer protocols. 相似文献
592.
Kathryn Kumagai Shimamura Scott Cheatham Wendy Chung Daniel Farwell Francisco De la Cruz Jennifer Goetz Kaleigh Lindblom Darcy Powers 《International Journal of Sports Physical Therapy》2015,10(1):1-12
Background
Pitchers may be at greater risk of injury in comparison to other overhead throwing athletes due to the repetition of the pitching motion. It has been reported that approximately 30% of all baseball injuries occur in the lower body. This may be related to limited hip mobility, which can compromise pitching biomechanics while placing excessive stress on the trunk and upper quarter. Hip motion and strength measurements have been reported in professional baseball pitchers but have not been reported in collegiate pitchers.Purpose
The purpose of this study was to report preliminary findings for passive hip motion and isometric hip muscle strength in collegiate pitchers and compare them to previously published values for professional level pitchers.Study Design
Cross sectional studyMethods
Twenty‐nine collegiate baseball pitchers (age = 20.0 + 1.4 years, height = 1.88 + 0.06 m; weight = 89.3 + 10.7 kg; body mass index = 25.3 + 2.5 kg/m2) were recruited. Subjects were assessed for hip internal rotation (IR) and external rotation (ER) passive motion, hip anteversion or retroversion, gluteus maximus, gluteus medius, hip internal rotator, hip external rotator strength, and lumbo‐pelvic control with the prone active hip rotation test as described by Sahrmann. Statistical analysis included calculation of subject demographics (means and SD) and use of a two‐tailed t‐test (p >0.05).Results
Fifty‐two percent of the right‐handed and 50% of the left‐handed pitchers demonstrated poor lumbo‐pelvic motor control with an inability to stabilize during active hip IR and ER even though isolated strength deficits were not detected at a significant level. There were no significant differences in hip passive motion or gluteus medius strength between right and left‐handed pitchers. Differences did exist between collegiate data and previously published values for professional pitchers for IR motion measured in prone and gluteus maximus strength. Hip retroversion was present in 55% of the pitchers primarily in both limbs with four of the pitchers presenting with retroversion singularly in either the stride or trail limb where the ER rotation motion was greater than the IR.Conclusion
Assessing mobility and muscle strength of the lower quarter in isolation can be misleading and may not be adequate to ensure the potential for optimal pitching performance. These findings suggest that lumbo‐pelvic control in relation to the lower extremities should be assessed as one functional unit. This is the first study to explore hip motion, strength, and lumbo‐pelvic control during active hip rotation in collegiate baseball pitchers.Evidence Level
2 相似文献593.
Figures WR; Scearce LM; DeFeo P; Stewart G; Zhou F; Chen J; Daniel J; Colman RF; Colman RW 《Blood》1987,70(3):796-803
Previous reports have indicated that the nucleotide affinity analog 5'- p-fluorosulfonylbenzoyl adenosine (FSBA) at concentrations between 40 and 100 mumol/L and at times greater than 20 minutes covalently modifies a single protein component on the external platelet membrane surface and that adenosine diphosphate (ADP) protects against this reaction. That this protein is an ADP receptor linked to platelet activation is shown by FSBA inhibition of ADP-mediated platelet shape change, aggregation, and fibrinogen receptor exposure. In this report, further evidence for the interaction of FSBA with the ADP receptor on platelets is provided by the observation that FSBA at high concentrations (100 to 500 mumol/L) behaves as a weak agonist to produce platelet shape change within one minute as detected by spectroscopic assay and scanning electron microscopy with concomitant phosphorylation of the light chain of platelet myosin. The specificity of FSBA as an agonist is demonstrated by inhibition of FSBA-induced shape change by ATP and the covalent incorporation of SBA as well as the failure of 5'-fluorosulfonylbenozoyl guanosine (FSBG) to cause shape change. In contrast, incubation of platelets with low concentrations of [3H]-FSBA (40 mol/L) is not associated with stimulation of platelet shape change or myosin light chain phosphorylation. 相似文献
594.
Wang LM; Michieli P; Lie WR; Liu F; Lee CC; Minty A; Sun XJ; Levine A; White MF; Pierce JH 《Blood》1995,86(11):4218-4227
Interleukin-13 (IL-13) induced a potent mitogenic response in IL-3- dependent TF-1 cells and DNA synthesis to a lesser extent in MO7E and FDC-P1 cells. IL-13 stimulation of these lines, like IL-4 and insulin- like growth factor-1 (IGF-1), resulted in tyrosine phosphorylation of a 170-kD substrate. The tyrosine-phosphorylated 170-kD substrate strongly associated with the 85-kD subunit of phosphoinositol-3 (PI-3) kinase and with Grb-2. Anti-4PS serum readily detected the 170-kD substrate in lysates from both TF-1 and FDC-P1 cells stimulated with IL-13 or IL-4. These data provide evidence that IL-13 induces tyrosine phosphorylation of the 4PS substrate, providing an essential interface between the IL- 13 receptor and signaling molecules containing SH2 domains. IL-13 and IL-4 stimulation of murine L cell fibroblasts, which endogenously express the IL-4 receptor (IL-4R alpha) and lack expression of the IL-2 receptor gamma subunit (IL-2R gamma), resulted in tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1)/4PS. Enhanced tyrosine phosphorylation of IRS-1/4PS was observed in response to IL-4, but not IL-13 treatment of L cells transfected with the IL-2R gamma chain. These results indicate that IL-13 does not use the IL-2R gamma subunit in its receptor complex and that expression of IL-2R gamma enhances, but is not absolutely required for mediating IL-4-induced tyrosine phosphorylation of IRS-1/4PS. 相似文献
595.
Weight gain and new onset diabetes associated with olanzapine and risperidone 总被引:2,自引:0,他引:2 下载免费PDF全文
Farwell WR Stump TE Wang J Tafesse E L'Italien G Tierney WM 《Journal of general internal medicine》2004,19(12):1200-1205
OBJECTIVE: To assess whether newer antipsychotic medications are associated with weight gain and development of diabetes. DESIGN: Retrospective cohort study. SETTING: Data from a comprehensive electronic medical record serving an urban public hospital and a citywide network of mental health clinics. PATIENTS/PARTICIPANTS: Three thousand one hundred fifteen patients at least 18 years old who were prescribed a single antipsychotic drug for at least 1 year. METHODS: We identified independent predictors of significant weight gain (> or =7%) and new onset of diabetes mellitus in the first year of antipsychotic drug treatment, using logistic regression adjusted for demographic characteristics, obesity, preexisting psychiatric diagnoses, alcohol and drug abuse, number of primary care, psychiatric clinic, and emergency department visits, and pretreatment weight. MEASUREMENTS AND MAIN RESULTS: Twenty-five percent of patients taking older phenothiazines developed significant weight gain in the first year of treatment compared to 40% of the patients taking olanzapine (adjusted odds ratio [OR], 2.8; 95% confidence interval [CI], 1.7 to 4.6; P <.0001) and 37% of patients taking risperidone (adjusted OR, 2.3; 95% CI, 1.5 to 3.4; P <.0001). New diabetes developed in 3% of patients taking older phenothiazines was new onset diabetes compared to 8.0% of patients taking olanzapine (adjusted OR, 1.9; 95% CI, 1.1 to 3.3; P=.03) and 3.5% of patients taking risperidone (adjusted OR, 0.7; 95% CI, 0.4 to 1.4; P=.3). No association was found between significant weight gain and developing diabetes (adjusted OR, 0.7; 95% CI, 0.4 to 1.4; P=.4). CONCLUSIONS: Olanzapine and risperidone use was associated with gaining weight in the first year, but only olanzapine was associated with developing diabetes mellitus. 相似文献
596.
The human cardiac mast cell: localization, isolation, phenotype, and functional characterization 总被引:5,自引:0,他引:5
Sperr WR; Bankl HC; Mundigler G; Klappacher G; Grossschmidt K; Agis H; Simon P; Laufer P; Imhof M; Radaszkiewicz T 《Blood》1994,84(11):3876-3884
We have isolated and characterized the human cardiac mast cell (CMC) and compared this novel mast cell (MC type with MC obtained from uterus, skin, and lung. Heart tissue was obtained from 14 patients with cardiomyopathy (CMP, heart transplantation). CMC were isolated by enzymatic digestion using collagenase, pronase-E, hyaluronidase, and DNAse. Substantial amounts of CMC (0.5% to 1.5% of isolated cells) were found in the atrial appendages but not in ventricular digests or other sites of the heart (< 0.1%). In situ staining of atrial tissue revealed the presence of CMC in the myocardium (2.16 +/- 0.7 MC/mm2), endocardium (2.24 +/- 0.9 MC/mm2), and epicardium. As assessed by combined toluidine blue/immunofluorescence staining with monoclonal antibodies (MoAbs), isolated CMC expressed surface IgE, the receptor for stem cell factor (c-kit receptor/CD117), the p24 antigen (CD9), the Pgp-1 homing receptor (CD44), the pan leukocyte antigen (CD45), and the ICAM-1 antigen (CD54). CMC were not recognized by MoAbs to lymphocyte function associated antigen 2 (LFA-2; CD2), T-cell receptor (TcR; CD3), T4 antigen (CD4), LFA-1 alpha-chain (CD11a), C3biR alpha-chain (CD11b), CR4 alpha-chain (CD11c), LPS-R related Ag (CD14), 3-FAL/x-hapten (CD15), Fc gamma RIII (CD16), lactosylceramid (CDw17), the B-cell antigen CD19, or CR1 (CD35). In situ expression of leukocyte antigens on CMC was demonstrable by indirect immunoperoxidase staining technique and double-labeling immunohistochemistry. Almost all CMC (90%) reacted with MoAbs against tryptase and chymase and thus were MCTC. Cardiac mast cells were also stained by the heparin-binding dye Berberine sulfate and expressed measurable amounts of histamine (4.6 +/- 1.4 pg per cell). Cross linking of either IgE receptor or SCF receptor (c-kit) on CMC resulted in histamine secretion (non-specific release: < 6% of total histamine, alpha IgE induced: 12% to 52%; SCF-induced release: 9% to 18%), whereas neither substance P (a skin MC agonist) nor the basophil agonist FMLP showed an effect on CMC. Together, the CMC is an MCTC primarily located in the appendage of the atrium. This novel type of MC exhibits surface membrane antigen and functional properties similar to those of lung and uterus MC. 相似文献
597.
Ruff Andrew Ballard Hatcher J. Pantel Austin R. Namoglu Esin C. Hughes Mitchell E. Nasta Sunita D. Chong Elise A. Bagg Adam Ruella Marco Farwell Michael D. Svoboda Jakub Sellmyer Mark A. 《Molecular imaging and biology》2021,23(6):818-826
Molecular Imaging and Biology - 18F-Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) is a well-established imaging modality to assess responses in patients with... 相似文献
598.
Flow cytometric detection of platelet-reactive antibodies and application in platelet crossmatching 总被引:1,自引:0,他引:1
M Kohler ; J Dittmann ; TJ Legler ; R Lynen ; A Humpe ; J Riggert ; H Neumeyer ; A Pies ; S Panzer ; WR Mayr 《Transfusion》1996,36(3):250-255
Background: Alloimmunization against HLA or platelet antigens can cause refractoriness to platelet transfusions in multiply transfused patients. Crossmatching of platelet concentrates is effective in overcoming this problem. Study Design and Methods: A flow cytometric assay was used for simultaneous detection of lymphocyte-reactive and platelet-reactive antibodies in a single sample using fluorescein isothiocyanate-labeled anti-IgG. This assay was compared with the monoclonal antibody-specific immobilization of platelet antigens (MAIPA) assay in selected sera containing HLA and platelet antibodies. In a further study, this assay was compared with lymphocytotoxicity test results from thrombocytopenic patients, for whom platelet concentrates were ordered. The results of both assays were then correlated with the 1-hour corrected count increment, with a corrected count increment greater then 7500 considered as an adequate transfusion response. Results: The results of the MAIPA and flow cytometric assay in detecting platelet-reactive antibodies correlated well (p<0.0001, r = 0.84). The sensitivity and specificity of the flow cytometric assay in detecting platelet-reactive antibodies were 94.7 and 96.3 percent, when the MAIPA assay was taken as a reference. In unselected sera from patients, the sensitivity and specificity of the flow cytometric assays were, respectively, 72.7 and 91.7 percent in detecting lymphocyte- reactive antibodies and 70.6 and 77.7 percent in detecting platelet- reactive antibodies, when the lymphocytotoxicity test was used as a reference. With regard to an adequate transfusion response, the sensitivities and efficiencies were 20.0 and 82.1 percent, 33.3 and 84.3 percent, and 70.0 and 88.6 percent for the lymphocytotoxicity test and the lymphocyte-reactive and platelet-reactive flow cytometric assays, respectively. Conclusion: Flow cytometric crossmatching appears to be an effective method of detecting platelet-reactive antibodies that may affect the success of platelet transfusions. This procedure is well-suited for routine conditions and can be performed within 2 hours. 相似文献
599.
Genetic and epigenetic changes in human epithelial cells immortalized by telomerase 总被引:21,自引:0,他引:21 下载免费PDF全文
Farwell DG Shera KA Koop JI Bonnet GA Matthews CP Reuther GW Coltrera MD McDougall JK Klingelhutz AJ 《The American journal of pathology》2000,157(5):1537-1547
Exogenous expression of hTERT, the catalytic component of telomerase, is sufficient for the immortalization of human fibroblasts but insufficient for the immortalization of human foreskin keratinocytes (HFKs) and human mammary epithelial cells (HMECs). These latter cell types can overcome senescence by coexpression of hTERT and human papillomavirus (HPV) E7 or by expression of hTERT and loss of p16(INK4a) expression, indicating that the retinoblastoma (Rb) pathway, along with a telomere maintenance pathway, plays a role in determining the life span of epithelial cells. In this study, we further characterize hTERT-immortalized HFKs and human adenoid epithelial cells (HAKs) for genotypic and phenotypic alterations that are associated with immortalization. Of five hTERT-immortalized HFK and HAK cell lines examined, four exhibited repression of p16(INK4a) expression by promoter methylation or specific large-scale deletion of chromosome 9p, the location of p16(INK4a). Interestingly, one cell line exhibited complete down-regulation of expression of p14(ARF), with only slight down-regulation of expression of p16(INK4a). Yet, all of the immortal cells lines exhibited hyperphosphorylated Rb. Cytogenetic analysis revealed clonal chromosome aberrations in three of the five cell lines. All of the cell lines retained a growth block response with the expression of mutant ras. When grown on organotypic raft cultures, however, the hTERT-immortalized cells exhibited a maturation delay on terminal differentiation. Our results indicate that immortalization of epithelial cells may require both activation of telomerase and other genetic and/or epigenetic alterations that abrogate normal differentiation. 相似文献
600.
Efficient conditional mutation of the vertebrate CENP-C gene 总被引:9,自引:1,他引:9
We have used gene targeting in the DT40 cell line to create a cell line
which expresses a fusion between CENP-C and a mouse steroid receptor and
which behaves as a conditional loss of function mutant of CENP-C. Under
restrictive conditions these cells arrest at the metaphase/anaphase
junction and after a delay of approximately 2.5 h die by apoptosis. These
results indicate that CENP-C is either necessary for anaphase chromosome
movement or for mediating a signal which triggers centromere function
during anaphase. Our approach is simple and applicable to a wide range of
proteins with general cell autonomous functions in vertebrates.
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