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41.
Platelet concentrates were prepared at twice the normal concentration and stored at room temperature for 7 days in either standard bags (controls) or bags to which 1 or 2 g of Amberlite resin beads charged with dibasic phosphate had been added. The resin beads served as a buffer system by providing a "slow release" form of phosphate ions as well as by binding CO2 produced during platelet metabolism. Control platelets demonstrated rapid falls in pH, ATP content, morphology score, and thrombin-induced nucleotide release after 24 hr of storage with a fall in pH to less than 6.0 by day 3. Profound ultrastructural changes and a rise in pO2, suggesting loss of platelet viability, accompanied these changes. In contrast, the resin-stored platelets remained near normal after 24 hr of storage, with preservation of discoid morphology, 95% of ATP levels, excellent ultrastructural appearance, and evidence of continued oxygen consumption after 3 days of storage. Even after 7 days of storage, ATP levels remained greater than 50% of baseline and ultrastructurally intact platelets were seen. In the 1-g resin bags the pH remained at baseline levels (6.9-7.0), while there was a rise in pH in the 2-g resin bags. These results demonstrate the beneficial effects of maintaining a higher pH during platelet storage and provide a new approach to studying the metabolic changes that occur during longer term storage. 相似文献
42.
Abruzzo LV; Schmidt K; Weiss LM; Jaffe ES; Medeiros LJ; Sander CA; Raffeld M 《Blood》1993,82(1):241-246
We describe a patient with angioimmunoblastic lymphadenopathy with dysproteinemia (AILD), who subsequently developed large-cell immunoblastic lymphoma of B-cell immunophenotype. At the time of the initial diagnosis, histologic examination of an inguinal lymph node showed typical features of AILD, and there was no evidence of a monoclonal B-cell population by immunohistochemical analysis. In situ hybridization and Southern blot analysis for Epstein-Barr virus (EBV) were negative. At autopsy 2 years later, the patient had widespread lymph node and organ involvement by large-cell immunoblastic lymphoma of B-cell immunophenotype. Southern blot analysis performed on DNA extracted from lymph nodes, liver, and spleen showed two patterns of Ig heavy chain and kappa light chain gene rearrangements. The T-cell receptor beta chain gene was in the germline configuration. Analysis with an EBV terminal repeat region probe showed two clonal populations that paralleled the Ig gene rearrangement studies. Double-labeling immunohistochemistry and in situ hybridization confirmed the presence of EBV within the neoplastic B cells. The data support the hypothesis that EBV was not etiologically related to AILD in this case, and that EBV proliferation may occur after the onset of the disease. Further, the data suggest that some B-cell lymphomas that arise in the setting of AILD resemble EBV-associated B-cell lymphomas that arise in other immunodeficiency states. 相似文献
43.
Effect of n-3 and n-6 fatty acids on proliferation and differentiation of promyelocytic leukemic HL-60 cells 总被引:9,自引:0,他引:9
Finstad HS; Kolset SO; Holme JA; Wiger R; Farrants AK; Blomhoff R; Drevon CA 《Blood》1994,84(11):3799-3809
Promyelocytic leukemic HL-60 cells were incubated with different fatty acids. Arachidonic acid (AA; 20:4, n-6) and eicosapentaenoic acid (EPA; 20:5, n-3) were the most potent inhibitors of proliferation in a dose- dependent way. Retinoic acid (RA) was used as a positive control. Inhibitors of cyclooxygenase and lipoxygenase or addition of antioxidants did not influence the effect of EPA or AA on cell proliferation. Increased capacity to generate superoxide anions after phorbol ester treatment and a reduced serglycin messenger RNA level in cells treated with AA or EPA indicated that these fatty acids induced differentiation in HL-60 cells similar to that induced by RA. However, down-regulation of the c-myc mRNA level, also typical for differentiation with RA in HL-60 cells, was not observed in cells incubated with AA or EPA. Flow cytometric analyses showed that in cultures incubated with AA or EPA, the proportion of cells in the G1 phase of the cell cycle increased. Similar effects were observed with RA. By flow cytometry and light scatter analyses it could be shown that AA made 8% of the cells apoptotic and 7% necrotic. The corresponding numbers were 21% and 10% for RA-treated cells, and 19% and 32% for EPA- treated cells. The present study shows that AA and EPA reduce the proliferation rate of HL-60 cells. This is mediated by mechanisms independent of eicosanoids or lipid peroxidation products and is due to effects both on apoptosis/necrosis and cell differentiation. 相似文献
44.
During the period from January 1970 until December 1973, therapy was started in 41 previously untreated adolescents and adults with acute lymphoblastic leukemia. Induction therapy was started with vincristine and prednisone in all patients, resulting in complete remission in 19 and death due to infection during the first month in one case. After 3 wk on these two drugs, the addition of daunorubicin was required in the remaining 21 patients. Fifteen of these obtained remission, one died during induction therapy, and five patients were unresponsive to this therapy, as well as to all subsequent induction schemes. The overall remission rate was 83%. Significantly higher initial leukocyte counts were found in the group treated with vincristine, prednisone, and daunorubicin. Meningeal leukemia prophylaxis, by either periodic methotrexate injections given intrathecally or a combination of cranial irradiation and intrathecally administrated methotrexate, was administered in 29 therapy responders. The median duration of complete remission obtained with various maintenance therapy schemes was 13 mo. No differences were seen in the results obtained in patients between 14 and 20 yr of age and older patients. Twenty-two patients relapsed within 2-37 mo. Relapses were confined to the central nervous system in two cases, to the bone marrow in 18, and to the bone marrow and CNS simultaneously in two. A second remission was obtained in 17 cases (77%). The median survival time of the whole group was 27 mo, as compared with 32 mo for therapy responders and 7 mo for the nonresponders. The percentage and duration of remission and the survival time in our group of adolescents and adults were comparable to those currently being achieved in other centers, but not as good as those reported for children treated with the same protocols. 相似文献
45.
Fetal persistent middle cerebral artery reversed end diastolic flow is a rare and ominous finding. Previous cases have been associated with intracranial hemorrhage, growth restriction, anaemia, and hepatic anomaly. Intrauterine demise or early neonatal death is a common outcome. We report the case of persistent middle cerebral artery reversed end diastolic flow in a well-grown fetus at 32 weeks’ gestation resulting from acute, severe anaemia due to a large feto-maternal hemorrhage. An emergency cesarean section was performed and the neonate required advanced resuscitation and immediate blood transfusion. Postnatal magnetic resonance imaging confirmed a hemorrhagic parietal infarct and bilateral ischaemic changes in the basal ganglia. This provides further evidence that persistent middle cerebral artery reversed end diastolic flow in any fetus is an ominous finding warranting urgent diagnostic evaluation and/or delivery. 相似文献
46.
G Bisi R Sciagrà G M Santoro G Cerisano A Vella F Zerauschek P F Fazzini 《Giornale italiano di cardiologia》1992,22(7):795-805
BACKGROUND. Tc-99m-teboroxime is a new tracer for myocardial perfusion scintigraphy. Its more remarkable features are the high myocardial extraction fraction, which is well correlated with the coronary blood flow, and the extremely rapid myocardial washout. This makes it necessary to complete the image collection shortly after the injection; on the other hand, repeated scans can be easily performed by renewed Tc-99m-teboroxime administrations. The aim of the present study was to test the feasibility of Tc-99m-teboroxime imaging and to evaluate its accuracy by comparing it with thallium-201 (TI-201) scintigraphy and coronary angiography. METHODS. The patient population included 16 male patients (mean age 57.8 +/- 6.3 years) affected by suspect effort angina and/or with signs of exercise-induced ischemia; 12 of them had history of previous myocardial infarction. They underwent effort TI-201 and Tc-99m-teboroxime myocardial scintigraphy within 48 hours; left heart catheterization and coronary angiography were performed within 5 days. Scintigraphic images were collected in 3 planar views; each projection was divided in 3 segments, with the apical one shared by all views, for a total of 7 segments/study. Tracer uptake was qualitatively assessed and graduated according to a scoring scheme (from 0 = normal through 4 = absent uptake). RESULTS. Tc-99m-teboroxime scans could be accomplished without major problems in all subjects. The image quality was comparable to TI-201 in 8 patients and poorer in the remaining 8. Coronary angiography showed 50% obstructions in 15 patients; of them 1 subject had a normal scintigraphic pattern with both TI-201 and Tc-99m-teboroxime. The presence of previous infarction was recognized by both tracers in the 12 patients with infarct history. The number of abnormal segments and the uptake score were not significantly different in the Tc-99m-teboroxime rest and in the TI-201 redistribution images (segments: 2.8 +/- 1.4 vs 2.8 +/- 1.6; score: 5.6 +/- 4.2 vs 6 +/- 4.5). The diagnosis of effort ischemia was made in 13 patients with Tc-99m-teboroxime and in 12 patients with TI-201. The number of abnormal segments in the exercise Tc-99m-teboroxime and TI-201 myocardial scintigraphy was not significantly different (3.3 +/- 1.3 vs 3.3 +/- 1.5); on the contrary the defect score was significantly higher with Tc-99m-teboroxime than with TI-201 (9.5 +/- 4.3 vs 8.4 +/- 4.6, p < 0.03). Therefore the ischemic score (exercise defect score minus rest defect score) of Tc-99m-teboroxime was significantly higher than that of TI-201 (3.9 +/- 2.8 vs 2.4 +/- 2.2, p < 0.02). The two tracers gave comparable results in terms of recognition of patients with one-vessel or multi-vessel coronary artery disease. CONCLUSIONS. Planar myocardial scintigraphy with Tc-99m-teboroxime can be performed without major problems. In terms of clinical reliability the results are comparable to those of TI-201 scans. On the other hand, taking into account the poor image quality of Tc-99m-teboroxime scintigraphy, it is still impossible to predict its future role in the radionuclide imaging of coronary artery disease. 相似文献
47.
Autologous bone marrow transplantation for acute myeloid leukemia using busulfan plus etoposide as a preparative regimen 总被引:1,自引:0,他引:1
We have studied the use of a new preparative regimen for the treatment of patients in remission of acute myeloid leukemia (AML) with autologous bone marrow transplantation. Chemotherapy consisted of busulfan 1 mg/kg every 6 hours for 4 days (total dose, 16 mg/kg) on days -7 through -4 followed by an intravenous infusion over 6 to 10 hours of etoposide 60 mg/kg on day -3. Autologous bone marrow, treated in vitro with 100 micrograms/mL of 4-hydroperoxycyclophosphamide, was infused on day 0. We have treated 58 patients up to the age of 60 years, 32 in first remission, 21 in second or third remission, and 5 with primary refractory AML unresponsive to high-dose Ara-C, but achieving remission with aggressive salvage regimens. Of the first remission patients, there has been 1 treatment related death and 5 relapses. With median follow-up of 22 months, the actuarial relapse rate is 22% +/- 9% and disease-free survival is 76% +/- 9% at 3 years. Patients with favorable French-American-British (FAB) subtypes (M3 or M4 EO) did especially well, with no relapses seen in 15 patients observed for a median of 30 months. Actuarial relapse rate at 3 years was 48% for first remission patients with less favorable FAB subtypes. Of patients in second or third remission, there were 5 treatment related deaths and 4 relapses. With median follow-up of 22 months, the actuarial relapse rate is 25% +/- 11% and disease-free survival is 56% +/- 11% at 3 years. Four of five primary refractory patients died during treatment and 1 remains in remission with short follow-up. These preliminary data are very encouraging and, if confirmed, support the use of autologous purged bone marrow transplantation using aggressive preparative regimens as one approach to improve the outcome of adults with AML. 相似文献
48.
BACKGROUND & AIMS: The functional significance of intestinal hyperplasia stimulated by insulin-like growth factor (IGF)-I is unclear and has not been studied in a model of mucosal atrophy induced by total parenteral nutrition (TPN). The aim of this study was to determine how IGF-I affects intestinal structure and epithelial function in the absence of luminal nutrition caused by TPN. METHODS: Rats were maintained with TPN with or without IGF-I (800 micrograms/day), and jejunal histology and epithelial ion transport were measured after 5 days. In a third TPN group without IGF-I, a short-term dose of IGF-I was added during in vitro flux chamber experiments. RESULTS: Rats given TPN with IGF-I had greater jejunal mucosal weight, greater protein and DNA content, and increased villus height and crypt depth compared with rats given TPN only. TPN increased ionic permeability and ion transport responses to secretory and absorptive agents. IGF-I in vivo reversed most of these changes; IGF-I in vitro enhanced sodium-dependent glucose absorption but had no other effects. CONCLUSIONS: Coinfusion of recombinant human IGF-I with TPN solution stimulates intestinal hyperplasia and attenuates transport changes induced by TPN. The latter effect seems to be primarily associated with the growth state of the epithelium. (Gastroenterology 1996 Dec;111(6):1501-8) 相似文献
49.
Corzo D; Yunis JJ; Salazar M; Lieberman JA; Howard A; Awdeh Z; Alper CA; Yunis EJ 《Blood》1995,86(10):3835-3840
Genes of the major histocompatibility complex (MHC) have been associated with susceptibility to drug-induced adverse reactions. We previously found that clozapine-induced agranulocytosis (CA) is associated with the HLA-DRB1*0402, DRB4*0101, DQB1*0302, DQA1*0301 haplotype in Ashkenazi Jewish patients and with the HLA-DRB1*1601, DRB5*02, DQB1*0502, DQA1*0102 haplotype in non-Jewish patients. In the present study, we tested the hypothesis that the variants of the heat- shock protein 70 (HSP-70) encoded by the HSP-70 loci located within the MHC region and known to be involved in apoptosis and regulation of cell proliferation could play an important role in molecular mechanisms of CA. First, we analyzed HSP70-2 polymorphism in risk-associated haplotypes from HLA homozygous cells and normal individuals and confirmed that the HSP70-2 9-kb variant was associated invariably with DR4 (HLA-DRB1*0402, DQB1*0302) and DR2 (HLA-DRB1*01601, DQB1*0502, DQA1*0102 and HLA-DRB1*1501, DQB1*0602) haplotypes, which were the haplotypes found increased in Jewish and non-Jewish patients with CA, respectively. The 9.0-kb variant was also found to be associated with HLA-B44, DRB1*0401 and HLA-B44, DRB1*07 haplotypes. Second, in patients with CA (12 Ashkenazi Jewish and 20 non-Jewish patients), HSP70-1 A and HSP70-2 9.0-kb variants were associated with the MHC haplotypes found by us to be markers of susceptibility to CA. The clozapine-treated control group had an excess number of HSP70-1 C and HSP70-2 8.5-kb variants, consistent with genetic resistance to CA associated with those variants. This finding supports our hypothesis that a dominant gene within the MHC region (marked by HSP70-1 and HSP70-2), but not necessarily HLA, is associated with CA in two different ethnic groups. 相似文献
50.
Caroline van Gemert Mark Stoove Tamara Kwarteng Siula Bulu Isabel Bergeri Ian Wanyeki Steve Badman Jayline Malverus Alyce Vella Len Tarivonda Lisa Grazina Johnston 《AIDS and behavior》2014,18(10):2040-2049
There is insufficient data on sexually transmitted infections (STI) and related behaviours among key populations, including female sex workers (FSW), in the Pacific region. Using respondent driven sampling, we conducted an integrated bio-behavioural survey with FSW in Vanuatu (aged ≥18 years) to investigate risk behaviours associations with Chlamydia trachomatis (CT). Weighted population estimates and correlates of CT infection were calculated. Among 149 FSW, prevalence of CT was 36 % (95 % CI 26–48 %). Few FSW reported consistent condom use with recent transactional sex partners (TSP) (8 %; 95 % CI 2–13 %). CT infection was positively associated with increasing number of TSP (adjusted odds ratio [AOR] 1.1; 95 % CI 1.0–1.2) and group sex (AOR 2.9; 95 % CI 1.1–8.2). CT was negatively associated with increasing age of first sex (AOR 0.6; 95 % CI 0.5–0.9) and previous STI treatment (AOR 0.1; 95 % CI 0.0–0.4). A comprehensive public health strategy for prevention and treatment of STI among FSW, incorporating community empowerment strategies, FSW-targeted health services and periodic presumptive treatment, is urgently needed in Vanuatu. 相似文献