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31.
Acquired granular pool defect in stored platelets   总被引:1,自引:0,他引:1  
Rao  AK; Niewiarowski  S; Murphy  S 《Blood》1981,57(2):203-208
Platelets stored as concentrates (PC) for 72 h at 22 degrees C develop a functional defect. Alterations in adenine nucleotides of platelets have been shown to affect platelet function. Adenine nucleotide content of platelets was measured before and after storage and a decrease of 27.1 /+- 1.7% (mean /+- SE) in ATP and 39.1 /+- 2.6% in ADP were found in 34 PC stored with final volume of 50 ml. In 11 PC with 30 ml volume. ATP and ADP decreased by 39.4 /+- 3.2% and 49.4 /+- 2.1%, respectively. The mean ATP to ADP ratio of stored platelets was significantly higher than of fresh platelets in both groups, suggesting a relatively greater decrease in granular than metabolic pool nucleotides. Levels of low affinity platelet factor 4 measured by radioimmunoassay in plasma from 0.86 /+- 0.08 microgram/ml in the fresh PC to 8.59 /+- 0.39 microgram/ml in stored PC, indicating a concomitant alpha-granular secretion. Labeling of metabolic pool with 14C-adenine revealed a mean decrease in the adenylate energy charge of 2.0 /+- 0.4% in 12 of 16 stored PC, with a lower ATP and higher hypoxanthine labeling in stored as compared to fresh platelets. These observations suggest that stored platelets develop an acquired defect in both dense and alpha granules and in their ability to maintain ATP homeostasis.  相似文献   
32.
The glutathione redox system and alpha-tocopherol, both of which are essential for maintaining the normal structure of biological membranes, some other lipid-soluble antioxidants (lycopene, beta-carotene, retinol), and lipid peroxidation, were investigated in the blood from two triosephosphate isomerase (TPI)-deficient brothers. Both of the genetically identical compound heterozygote brothers have congenital hemolytic anemia, but only one of them has a neurological defect, the second cardinal symptom of TPI deficiency. Whole blood reduced glutathione levels were markedly decreased in both brothers. The glutathione reductase activities as well as the NADPH contents of their erythrocytes were in the normal range or slightly enhanced. Increased ratio of oxidized/reduced glutathione, elevated glutathione S-transferase activity, and increased d-lactate level, a metabolite of the glyoxalase pathway, were detected only in the neurologically affected propositus. The plasma carotenoids (lycopene + beta-carotene), alpha-tocopherol/cholesterol + triglyceride ratios, and the erythrocyte alpha-tocopherol levels were significantly decreased in both patients. It seems conceivable that membrane alterations due to the low level of these reducing agents may contribute to the shortened life span of erythrocytes. The imbalance of the prooxidant/antioxidant homeostasis as well as the increased rate of methylglyoxal formation may also have been involved in the development of the neurological manifestations in the propositus.  相似文献   
33.
T Sauerbruch  J Holl  M Sackmann    G Paumgartner 《Gut》1992,33(7):969-972
Extracorporeal shock wave lithotripsy of pancreatic duct stones (largest stone 12 (SD) 6 mm) was performed in 24 patients with abdominal pain and a dilated duct system (main pancreatic duct 10 (3) mm). The procedure was well tolerated in all but two patients, who had a mild pancreatitic attack immediately after lithotripsy. Disintegration of the stones was achieved in 21 patients. This allowed complete clearance of the duct system by an endoscopic approach in 10 (42%) patients and partial clearance in 7 (29%) patients. Within a mean follow up period of 24 (14) months half of the patients showed complete or considerable relief of pain and alleviation of symptoms was achieved in seven patients. Relief of pain occurred more often after complete ductal clearance. There were no fatalities within the follow up period. These findings underline the value of a combined non-surgical approach, using endoscopy and adjuvant shock wave lithotripsy to patients with large pancreatic calculi and pain attacks.  相似文献   
34.
Reduced dynamic knee stability, often evaluated with one‐leg hops (OLHs), is reported after anterior cruciate ligament (ACL) injury. This may lead to long‐standing altered movement patterns, which are less investigated. 3D kinematics during OLH were explored in 70 persons 23 ± 2 years after ACL injury; 33 were treated with physiotherapy in combination with ACL reconstruction (ACLR) and 37 with physiotherapy alone (ACLPT). Comparisons were made to 33 matched controls. We analyzed (a) maximal knee joint angles and range of motion (flexion, abduction, rotation); (b) medio‐lateral position of the center of mass (COM) in relation to knee and ankle joint centers, during take‐off and landing phases. Unlike controls, ACL‐injured displayed leg asymmetries: less knee flexion and less internal rotation at take‐off and landing and more lateral COM related to knee and ankle joint of the injured leg at landing. Compared to controls, ACLR had larger external rotation of the injured leg at landing. ACLPT showed less knee flexion and larger external rotation at take‐off and landing, and larger knee abduction at Landing. COM was more medial in relation to the knee at take‐off and less laterally placed relative to the ankle at landing. ACL injury results in long‐term kinematic alterations during OLH, which are less evident for ACLR.  相似文献   
35.
IntroductionPostoperative pain after breast surgery is one of the major factors contributing to delay in mobilisation and prolonged hospital stay. A retrospective analysis was performed of patients undergoing skin sparing mastectomy and insertion of a subpectoral implant. The aim was to determine whether the use of an elastomeric local anaesthetic pump improved pain control and length of stay.MethodsTwenty-five consecutive patients undergoing the above procedure were sited with an elastomeric local anaesthetic infusion pump intraoperatively, in addition to standard regular and pro re nata analgesia. The control group comprised 25 patients undergoing the same procedure in the same year who received standard analgesia alone. Visual analogue scale scores were recorded for the duration of inpatient stay, as was any further analgesic requirement.ResultsThe median age was 51 years (range: 26–75 years) in the intervention group and 50 years (range: 28–70 years) in the control group. The mean visual analogue scale score was 0.28 (standard deviation [SD]: 0.61) at 24 hours for the intervention group and 1.84 (SD: 0.37) for the control group (p<0.0001). The mean length of stay was 1.8 days (SD: 0.71 days) for the intervention group and 2.28 days (SD: 0.94 days) for the control group (p=0.15). There were no complications involving catheter placement, leakage or toxicity relating to use of the local anaesthetic.ConclusionsThere was significantly reduced pain with the use of the local anaesthetic infusion pump. The elastomeric pump is a step towards enhanced patient recovery after breast surgery in the case of skin sparing mastectomy and subpectoral tissue expander reconstruction.  相似文献   
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38.
Siefer  AK; Longo  DL; Harrison  CL; Reynolds  CW; Murphy  WJ 《Blood》1993,82(8):2577-2584
Purified populations of natural killer (NK) cells were obtained from mice with severe combined immune deficiency (SCID). SCID spleen cells were cultured and activated with recombinant human interleukin-2 (rhIL- 2) in vitro. The activated NK cells were then transferred with syngeneic BALB/c bone marrow cells (BMC) and rhIL-2 into lethally irradiated syngeneic recipients to determine their effect on long-term hematopoietic reconstitution. On analysis, the transfer of rhIL-2- activated NK cells along with BMC resulted in significant increases in splenic and BM hematopoietic progenitor cells when compared with those for mice not receiving NK cells. Histologic and flow cytometric analysis showed a marked increase in granulocytic and megakaryocytic lineage cells present in the spleens of the mice receiving activated NK cells. Analysis of the peripheral blood indicated that the transfer of activated NK cells with BMC also significantly improved platelet and total white blood cell counts, with increases in segmented neutrophils. Erythroid recovery was not affected. Finally, lethally irradiated mice receiving activated NK cells and rhIL-2 along with limiting numbers of syngeneic BMC showed a marked increase in survival rate. These results show that the use of populations enriched for activated NK cells after syngeneic BM transplantation (BMT) has a profound enhancing effect on engraftment primarily affecting megakaryocytic and granulocytic cell reconstitution. Therefore, the transfer of activated NK cells and rhIL- 2 may be of clinical use to promote hematopoietic reconstitution after BMT.  相似文献   
39.
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   
40.
Diarrhoea and weight loss are frequently reported adverse events in rheumatoid arthritis (RA) patients receiving the disease-modifying antirheumatic drug (DMARD) leflunomide. According to the available literature these side effects occur mostly during the first 6 months of treatment, are rather mild and rarely lead to treatment withdrawal. In this report, we describe the clinical, endoscopic and histologic findings in two RA patients with severe diarrhoea and important weight loss more than 12 months after starting treatment with leflunomide. In both cases the symptoms were caused by colitis, but one had ulcerative and the other microscopic colitis. Despite treatment with budesonide the complaints only improved after withdrawal of leflunomide, making a causal relationship between this drug and the pathogenesis of colitis probable. The heterogeneous histopathological findings in these two patients, however, do not allow us to draw any definitive conclusions about the mechanism by which leflunomide causes diarrhoea and weight loss in RA patients. We conclude that persistent diarrhoea or weight loss in patients taking leflunomide can be more serious than what is previously reported in the literature. In such cases leflunomide treatment should be stopped and an endoscopic examination of the colon is recommended. Given the long half-life of this drug a washout procedure with cholestyramine should be considered whenever the problem is severe or persistent.  相似文献   
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