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991.
In recent years a large number of coronary artery disease risk factors were discovered. The knowledge of these factors improves the estimate of the coronary artery disease (CAD) risk--however it still remains to be only an "estimate". A perfect prediction of an upcoming CAD event is not possible, despite all high score laboratory technology. Therefore the use of specialized laboratory procedures should be applied carefully. Knowing the blood levels of cholesterol, triglycerides, HDL- and LDL-cholesterol and Lp(a) can be sufficient for many therapeutical decisions. Severe dyslipidemia, familial CAD and CAD without any obvious reasons demand a more specialized work-up, however, risk stratification factors such as family history, clinical history (CAD, hypertension, diabetes mellitus, smoker) and genetics are crucial, apart from the above mentioned laboratory values. Purely on the basis of the lipidologic baseline concentrations we can't give well based recommendations for the treatment of individual patients. Currently there are expert systems available which allow a risk estimate once important laboratory values (LDL cholesterol, HDL cholesterol, Triglycerides) as well as clinical data (blood pressure, family history, clinical history) are available. This system can be accessed by internet under "http:/(/)www.chd-taskforce.com". 相似文献
992.
Neutrophil transfusion: effect of storage and of collection method of neutrophil blood kinetics 总被引:1,自引:0,他引:1
The kinetics in blood of autologous neutrophils collected by phlebotomy, filtration leukapheresis (FL), or intermittent-flow centrifugation (IFC), labeled with 32P-diisopropylfluorophosphate, and stored at 4 degrees C for up to 2 days were measured in 41 normal subjects. Mean initial recovery for unstored IFC cells was 34.0%, compared to 7.9% for unstored FL cells. Blood half-lives were 4.1 and 2.7 hr for unstored IFC and FL cells, respectively. With neutrophils collected by phlebotomy and stored in whole blood for 1-2 days, posttransfusion recoveries and blood half-times were significantly decreased. Storage of both IFC and FL preparations resulted in only moderate kinetic abnormalities in comparison to the unstored cells. These studies indicate that the ability of unstored IFC cells to circulate is basically normal, whereas that of unstored FL cells is significantly impaired. The data further suggest that these neutrophil concentrates might be stored for 1-2 days prior to transfusion. 相似文献
993.
STUDY OBJECTIVES: Different beta-agonists are compared with regard to their cardiodepressive side effects. DESIGN: The metaphenolic bronchodilators reproterol, salbutamol, fenoterol, and terbutaline were introduced at a dosage of 0.0005 micromol to a maximum of 10 micromol per gram of heart tissue into the isolated working rat heart under hypoxic conditions, and the response was observed during subsequent reoxygenation. As an index of external heart work, aortic flow was measured. Heart rate, coronary flow, and developed pressure were recorded. At the end of heart perfusion, mitochondria were isolated and analyzed for adenosine triphosphatase activity, adenosine triphosphate (ATP) synthesis, and membrane fluidity. Moreover, intact mitochondria and lipid peroxidation were investigated using a model system. Measurements and results: Compared to controls, reproterol gave the most favorable results, with an increase of 25 to 30% of aortic flow during reoxygenation at a concentration of 10 micromol/g heart tissue. In contrast, both fenoterol and salbutamol at a concentration of 1 micromol/g heart tissue decreased aortic flow during reoxygenation, whereas terbutaline had a negative influence on aortic flow at 0.01 to 0.1 micromol/g heart tissue. Mitochondria of these hearts were isolated at the end of the experiment. Mitochondrial ATP synthesis was increased above controls at nearly all concentrations of reproterol. ATP synthesis was decreased at 1 micromol and 10 micromol fenoterol. As little as 0.0005 micromol terbutaline decreased ATP synthesis by 50%. In intact mitochondria, adenosine diphosphate (ADP) to oxygen ratios were found to be increased with terbutaline and fenoterol, indicating ADP consumption by myokinase activation. Lipid peroxidation was increased in a model system between concentrations of 0.002 micromol/mg and 0.04 micromol/mg phosphatidylcholine by fenoterol and terbutaline, whereas a decrease was noted with reproterol. Membrane fluidity was found increased after addition of reproterol, which supports the evidence of efficient ATP synthesis by this compound. CONCLUSIONS: Cardiodepressive side effects and greater toxicity of fenoterol and terbutaline were found under the conditions of our experiment. Salbutamol and, in particular, reproterol appear much better tolerated. In addition to partial beta-adrenergic agonism, reproterol may exert an inhibitory influence on adenosine receptor sites and phosphodiesterase, which could result in membrane stabilization by saving cyclic adenosine monophosphate or ATP. 相似文献
994.
Glucocorticoids inhibit apoptosis of human neutrophils 总被引:6,自引:2,他引:6
Human neutrophils rapidly undergo apoptotic cell death. Because glucocorticoids are known to modulate an array of neutrophil functional activities as well as induce rapid apoptosis in susceptible lymphocyte populations, we have examined the effects of glucocorticoids on apoptosis in mature human neutrophils. In cultures of neutrophils maintained in vitro, the glucocorticoids, dexamethasone, 6 alpha- methylprednisolone, and hydrocortisone, inhibited the development of apoptotic morphology by 59% to 90% when assessed at 12, 24, and 48 hours. In contrast, corticosteroids lacking anti-inflammatory activity and progesterone failed to affect development of the morphologic features of apoptosis. The concentration of dexamethasone required to reduce apoptosis by 50% at 24 hours was approximately 5 x 10(-8) mol/L, a concentration that is achievable in plasma after dexamethasone treatment. Dexamethasone (10(-6) mol/L), but not progesterone, reduced the percentage of hypodiploid (apoptotic) nuclei by 40% to 90% over this time course. Similarly, dexamethasone reduced the DNA cleavage associated with apoptosis and prolonged the viability of neutrophils maintained in culture for 12 to 48 hours. Glucocorticoid-mediated modulation of neutrophil apoptosis was qualitatively similar, but lesser in magnitude, when compared with the effects of granulocyte colony-stimulating factor (100 ng/mL). Thus, glucocorticoids exert a protective effect on human neutrophil survival by delaying apoptosis. 相似文献
995.
Previous studies have shown that tumor-specific bcr-abl mRNA can often be detected by polymerase chain reaction. (PCR) for months to years after allogeneic bone marrow transplantation (BMT) for chronic myelocytic leukemia (CML). Nevertheless, the presence of bcr-abl mRNA by itself does not invariably predict for clinical relapse post-BMT. This has led to the hypothesis that bcr-abl mRNA might be expressed in cells that have lost either proliferative or myeloid differentiation potential. To directly characterize the cells detected by PCR in patients with CML after allogeneic BMT, we first identified five individuals in whom PCR-positive cells could be detected at multiple times post-BMT. Bone marrow samples from these individuals were cultured in vitro and single erythroid, granulocytic, and macrophage colonies, each containing 50 to 100 cells, were examined for the presence of bcr-abl mRNA by PCR. PCR-positive myeloid colonies could be detected in four of five individuals in marrow samples obtained 5 to 56 months post-BMT. Overall, 7 of 135 progenitor cell colonies (5.2%) were found to be PCR-positive. The expression of bcr-abl mRNA appeared to be equally distributed among committed erythroid, macrophage, and granulocyte progenitors. These patients have now been followed-up for an additional 20 to 33 months from the time of progenitor cell PCR analysis but only one of these individuals has been found to have cytogenetic evidence of recurrent Ph+ cells. These results show that long-term persistence of PCR-detectable bcr-abl mRNA after allogeneic BMT can be caused by the persistence of CML-derived clonogenic myeloid precursors that have survived the BMT preparative regimen. These cells continue to have both proliferative and myeloid differentiation capacity in vitro. Nevertheless, these PCR-positive cells do not appear to either expand or differentiate in vivo for prolonged periods, suggesting the presence of mechanisms for suppression of residual clonogenic leukemia cells in vivo. 相似文献
996.
Timed-sequential induction therapy improves postremission outcome in acute myeloid leukemia: a report from the Children's Cancer Group 总被引:3,自引:12,他引:3
Woods WG; Kobrinsky N; Buckley JD; Lee JW; Sanders J; Neudorf S; Gold S; Barnard DR; DeSwarte J; Dusenbery K; Kalousek D; Arthur DC; Lange BJ 《Blood》1996,87(12):4979-4989
Timed sequencing of cycles of induction chemotherapy in acute myeloid leukemia (AML) has been proposed as a way to achieve maximal leukemic cell kill through recruitment and synchronization of residual neoplastic cells. Furthermore, whether intensive induction therapy should be continued in the presence of profound myelosuppression is an important question. The Children's Cancer Group (CCG) conducted a prospective randomized trial in which 589 patients with AML were randomized at diagnosis to one of two induction approaches involving a 4-day cycle of five active chemotherapeutic agents, with the second cycle administered either 10 days after the first cycle, despite low or dropping blood counts (intensive timing), or 14 days or later from the beginning of the first cycle, depending on bone marrow status (standard timing). All patients achieving remission received a total of four cycles of induction therapy. They were then allocated to allogeneic bone marrow transplantation (BMT) if a compatible family donor was present or randomized to aggressive nonmyeloablative therapy or to myeloablative therapy with purged autologous BMT rescue. The three postremission arms remain coded. Induction success and median days to complete induction were similar for the 295 patients randomized to the intensive timing arm (75%, 99 days) compared with the 294 patients randomized to the standard timing arm (70%, 105 days; P = .18 for remission). However, a marked improvement in outcome was demonstrated in patients randomized to the intensive timing arm, with an actuarial event-free survival at 3 years of 42% +/- 7% (95% confidence interval [CI]) versus 27% +/- 6% for patients on the standard timing arm (P = .0005). Disease-free survival results at 3 years from the end of induction were superior for patients receiving intensively timed induction therapy (N = 211), 55% +/- 9% versus 37% +/- 9% for standard timing patients (N = 195, P = .0002), with a median follow-up from achieving remission of 28 months. Superior results were documented for patients receiving intensive timing irrespective of the postremission therapy to which they were allocated. Intensively timed induction therapy for patients with AML markedly improves event-free survival, even for patients undergoing myeloablative therapy with BMT rescue. Without controlling for the type of induction therapy received, results of various BMT studies in AML comparing different preparative regimens will be difficult to interpret. 相似文献
997.
998.
Watanabe T; Kuszynski C; Ino K; Heimann DG; Shepard HM; Yasui Y; Maneval DC; Talmadge JE 《Blood》1996,87(12):5032-5039
Human bone marrow mononuclear cells (BMMNCs) and enriched CD34 positive (CD34+) cells were transduced with adenovirus vectors encoding Escherichia coli beta-galactosidase gene. Tranductions were carried out by 24-hour coincubation with adenovirus vectors at different multiplicities of infections (moi). Efficacy of gene transfer into BM cells and expression of the gene product (ie, beta-galactosidase) were studied using X-Gal histochemical staining and flow cytometric analysis. X-Gal staining demonstrated that the percentage of positive cells at mois of 5 to 500 was 3.4% to 34.5% for BMMNCs and 6.0% to 20.0% for enriched CD34+ cells. Similar results (1.5% to 35.7% for BMMNCs and 5.4% to 24.2% for enriched CD34+ cells) were obtained with flow cytometric analysis using fluorescein di-beta-D-galactopyranoside (FDG). Multicolor flow cytometry analysis, which included FDG, demonstrated that BM progenitors (CD34+ or CD34+CD38-), T cells (CD2+), B cells (CD19+), natural killer cells (CD56+), granulocytes, and monocytes all expressed the adenovirus transgene. To ascertain the effects of adenovirus vectors on normal BM progenitors, the numbers of colony forming unit-granulocyte/macrophage (CFU-GM), burst-forming unit- erythrocyte (BFU-E), and high-proliferative potential-colony-forming cells (HPP-CFC) after 24-hour coincubation with adenovirus vectors were determined. When BMMNCs or enriched CD34+ cells were incubated with adenovirus vectors at mois of 5 and 50, no significant differences in the numbers of CFU-GM, BFU-E, and HPP-CFC were observed compared with the uninfected control cells. However, the numbers of CFU-GM were significantly (P < .01) decreased when BMMNCs or enriched CD34+ cells were incubated with adenovirus vectors at a moi of 500, compared with the uninfected control cells. The adenovirus infected cells, purified by cell sorting for FDG expression, were capable of growing in culture and gave rise to various colonies (ie, CFU-GM, BFU-E, and HPP-CFC). These data indicate that recombinant adenovirus vectors can be used to transfer genes to human BM hematopoietic cells with expression of the exogenous gene at a high transduction efficiency. 相似文献
999.
Gillio AP; Faulkner LB; Alter BP; Reilly L; Klafter R; Heller G; Young DC; Lipton JM; Moore MA; O'Reilly RJ 《Blood》1993,82(3):744-751
This report describes the response of eighteen Diamond-Blackfan anemia (DBA) patients to recombinant human interleukin-3 (rhIL-3). rhIL-3 was administered subcutaneously once daily on an escalating dose schedule (0.5 to 10 micrograms/kg/d). The rhIL-3 dose was escalated every 21 days until erythroid response was attained, grade III or IV nonhematologic toxicity was observed, or the maximum rhIL-3 dose was reached. Four patients experienced clinically significant erythroid responses. Two of the responders were steroid-dependent and transfusion- independent, while two were steroid-independent and transfusion- dependent. Baseline clinical or laboratory parameters, in particular in vitro bone marrow erythroid progenitor assays, were not useful in predicting rhIL-3 response. rhIL-3 administered at 5 to 10 micrograms/kg/d was associated with an increase in total white blood cell count, secondary to increases in neutrophils, eosinophils, and lymphocytes. Patients experienced a dose-dependent elevation in absolute eosinophils across the entire dose range. Two of the responding patients remain on maintenance rhIL-3, without diminution of effect at 244 and 370 + days. rhIL-3 was discontinued in the other two responders, because of the development of deep venous thrombi. 相似文献
1000.
DC Whitcomb RA Preston CE Aston MJ Sossenheimer PS Barua Y Zhang A Wong- Chong GJ White PG Wood LK Gates Jr C Ulrich SP Martin JC Post GD Ehrlich 《Gastroenterology》1996,110(6):1975-1980
BACKGROUND & AIMS: Hereditary pancreatitis (HP) is an autosomal- dominant disorder with incomplete penetrance characterized by recurrent bouts of severe epigastric pain with onset usually at 5-10 years of age. A genetic linkage study was designed to identify the HP gene. METHODS: A 500-member pedigree was constructed from a U.S. kindred centered in eastern Kentucky and western Virginia. A genome-wide search strategy was employed using a 36-member subset of this family to determine the genetic locus for HP. Testing for linkage to microsatellite loci was performed at 20-cM intervals. RESULTS: Linkage was established between the HP phenotype and chromosome 7q in this subset of the family. Modeled as an autosomal dominant disorder with 80% penetrance, a maximal multipoint logarithm of the odds score of 4.3 was obtained using a four-point analysis consisting of markers D7S684, D7S661, D7S505, and the HP locus. Two microsatellite markers, D7S661 and D7S505, that correspond to the 7q35 region of chromosome 7 spanning a 6-cM region did not evidence obligate recombinations with HP. The centromeric and telomeric limits are defined by recombinations at D7S684 and D7S483, respectively, which generates a 19-cM locus for HP. Utilizing family members from the extended pedigree, a break in the high-risk haplotype between D7S684 and D7S661 was observed, which suggests it may be possible to exclude an additional 8 cM from the HP locus. A maximal pairwise logarithm of the odds score of 4.73 at a recombination fraction of theta at D7S684 was obtained with the addition of these extended family members. CONCLUSIONS: Linkage of HP to 7q35 represents a major advancement in our understanding of the genetic basis of this disorder. (Gastroenterology 1996 Jun;110(6):1975-80) 相似文献