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31.
BACKGROUND: Granulocyte collection relies on the use of a red cell- sedimenting agent and is influenced by poorly defined intrinsic donor characteristics. The donor's baseline red cell (erythrocyte) sedimentation rate (ESR), a readily measurable intrinsic donor variable, may influence the effectiveness of red cell-sedimenting agents and affect the granulocyte yield. STUDY DESIGN AND METHODS: The in vitro and in vivo effects of 6-percent hydroxyethyl starch on the donor ESR were prospectively studied in 67 granulocytapheresis procedures with a blood cell separator, and the findings were correlated with granulocyte collection efficiency (GCE). A relationship that predicts the GCE on the basis of the donor ESR was then derived and tested. RESULTS: The 3.7-fold mean increase in the donor ESR measured after in vitro addition of hydroxyethyl starch approximated the 3.3-fold increase measured when it was administered to the donors. Higher baseline ESR correlated with larger in vitro and in vivo hydroxyethyl starch-induced increases in ESR and predicted more efficient cell collections and greater cell yields. Furthermore, both ESR and GCE, which varied significantly among donors, remained constant for a given donor undergoing repeat procedures. The results could be summarized by a simple predictive formula that relates the GCE (%) to the ESR (mm/hour): GCE = 1.3ESR + 45. The GCE and yield as predicted by the formula were accurate within 10 percent of the observed values in six subsequent procedures. CONCLUSION: In granulocyte harvests using a blood cell separator with hydroxyethyl starch as the sedimenting agent, 1) both ESR and GCE vary widely among donors yet may remain relatively constant for a given donor; 2) the baseline ESR correlates with hydroxyethyl starch-modified ESR and with GCE; and 3) it may be possible to predict GCE and yield from the donor's baseline ESR. 相似文献
32.
White cells (WBCs) present in stored platelet concentrates have adverse effects on platelet function and on posttransfusion recovery. Although these effects have been attributed to the fall in pH that results from active WBC metabolism, platelets stored in gas-permeable storage bags still exhibit abnormalities, despite maintenance of a stable pH of greater than 6.0. The changes in platelet proteins and function brought about by storage with a controlled number of WBCs were studied. Twelve platelet-pheresis specimens were centrifuged at 180 x g to achieve a WBC count of less than 2 x 10(5) per mL (which contained less than 10% granulocytes). These specimens were split into two aliquots and placed in platelet bags for storage at 22 degrees C with constant horizontal agitation. Neutrophils, obtained from the same donor by centrifugation of 50 mL of whole blood through a discontinuous ficoll gradient, were added to one of the two platelet storage bags to achieve a final neutrophil count of 1 x 10(6) per mL. Platelet aliquots were removed and studied on Days 3 and 5. In platelets stored without neutrophils, the average response to ristocetin, using the mean slope as an index of platelet responsiveness, was 10.3 (n = 9, SD = 11) on Day 3, whereas for the platelets stored with neutrophils, it was 1.25 (n = 12, SD = 0.9, p less than 0.01). Significant differences were also seen on Day 5 (slope = 4.5 for platelets stored without neutrophils, slope = 0.3 for platelets stored with neutrophils, p less than 0.01). Platelet aggregation with 8 microM ADP and 1.5 mg per mL of collagen did not differ significantly.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
33.
Pre-B cells and other possible precursor lymphoid cell lines derived from patients with X-linked agammaglobulinemia 总被引:14,自引:6,他引:14
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SM Fu JN Hurley JM McCune HG Kunkel RA Good 《The Journal of experimental medicine》1980,152(6):1519-1526
A group of unique Epstein-Barr virus-containing cell lines was derived from the bone marrow of three patients with X-linked agammaglobulinemia. Efforts to obtain cell lines from the peripheral blood of these patients were uniformly unsuccessful. Immunofluorescence analyses as well as biosynthetic studies with [(35)S]methionine indicated unusual patterns of Ig synthesis in many of these bone marrow derived lines. Seven of the lines were of particular interest in that two produced no Ig of any type; two others showed no Ig by fluorescence but small amounts by [(35)S]methionine labeling; one expressed only cytoplasmic μ chains without any evidence of light chain synthesis, and two produced primarily μ chains with only slight amounts of light chains. One of the lines without membrane or cytoplasmic Ig studied in detail grew like a typical lymphoid line and was carried in intermittent culture over a period of 2 yr without Ig expression. One line grew quite differently and resembled the round cell type described previously, which has been obtained from a variety of sources. The cell line with cytoplasmic μ chains and no light-chain expression had the characteristic properties of pre-B cells. Three normal type Ig-producing cell lines also were obtained from the patients. The accumulated evidence obtained in the present study indicates that these unusual cell lines represent normal precursor cells of the B-cell lineage; these grew out in these cases because of the virtual absence of mature B cells that ordinarily overgrow the culture system. However, the possibility that in certain instances they reflect abnormal Ig synthesis characteristic of the disease has not been ruled out. 相似文献
34.
Interdigestive small bowel motility and duodenal bacterial overgrowth in experimental acute pancreatitis 总被引:10,自引:0,他引:10
I. D. Van felius L. M. A. akkermans K. bosscha A. Verheem W. Harmsen† M. R. Visser† & H. G. Gooszen 《Neurogastroenterology and motility》2003,15(3):267-276
The objective of this study is to investigate the effects of an acute necrotizing pancreatitis (ANP), without biliary obstruction, on the migrating motor complex (MMC), small bowel bacterial overgrowth (SBBO), bacterial translocation (BT) and infection of the pancreas simultaneously. Rats were divided into four groups: mild pancreatitis, control, ANP and sham operated control. Jejunal myoelectrodes were used to measure MMCs. Blood, peritoneal fluid, bile, and abdominal organs were harvested for microbial culturing 72 h after induction of pancreatitis. The splenic portion of the pancreas was taken for histology. During ANP the MMC cycle length was significantly increased from 14.1 +/- 0.2 to 22.4 +/- 1.9 min (P < 0.05). The duodenum of ANP rats was in contrast with the other groups characterized by Enterobacteriacae (> 3 log 10 CFU g-1 in seven of 12 rats, P < 0.05). A positive correlation (r = 0.78, P < 0.01) existed between duodenal Gram-negative and anaerobic flora and the MMC cycle. Correlation between MMC cycle length and BT to the pancreas was positive as well (r = 0.70, P < 0.01). A positive correlation (r = 0.85, P < 0.01) was found between the severity of pancreatitis and duodenal bacterial overgrowth. During ANP without biliary obstruction, the jejunal MMC is disturbed and consequently SBBO occurs. The correlation between the severity of pancreatitis, the disturbance of the MMC and SBBO suggests an important pathophysiological role of the proximal small bowel in the infection of pancreatic necrosis. 相似文献
35.
36.
白介素与溃疡性结肠炎 总被引:17,自引:1,他引:17
近年来对白介素(interleukin,IL)和溃疡性结肠炎(ulcerative colitis,UC)的研究取得了很大进展,我们通过总结整理以前有关IL和UC的文献,概括出IL的产生和在UC发病及病理变化中的作用机制:IL-1直接介导了UC初期阶段炎症的发生:IL-8、IL-6直接促进炎性细胞过度分泌和/或抑制了炎性细胞的凋亡,IL-2分泌减少导致免疫系统内细胞间网络调节失衡, 使局部炎症介质和自由基释放,引起细胞毒作用,IL主要通过影响机体整体和/或局部免疫系统的功能介导UC的产生,并与UC的迁延难愈和反复发作有关. 相似文献
37.
Background In order to know the role of gastric emptying in the mechanism of weight loss and early satiety after a restrictive surgical
procedure for treatment of morbid obesity, a consecutive series of patients were scintigraphically investigated before and
after laparoscopic adjustable gastric banding.
Methods Sixteen patients undergoing laparoscopic adjustable gastric banding underwent preoperatively, and at 6 months postoperatively,
a gastric emptying study (solid meal and single isotope). Esophageal retention time, lag phase, peak activity time, gastric
emptying rate, fundus emptying rate, and weight loss were recorded. Upper GI symptom assessment was carried out by using a
standardized questionnaire. Gastric emptying parameters were correlated with the upper GI symptoms.
Results Gastric band placement showed no significant influence on postoperative gastric emptying rate [median % (interquartile range):
42 (23.3–59) preoperatively vs 38 (31–71) postoperatively and fundus emptying rate: 59(37–91) preoperatively vs 70 (53–89)
postoperatively]; however, an increase in early satiety was found. Neither gastric emptying rate nor fundus emptying rate
showed a relation with early satiety or weight loss. Furthermore, no correlation was found between early satiety and lag phase,
esophageal retention time, start of activity, and peak activity time in proximal stomach.
Conclusion Laparoscopic adjustable gastric banding seems not to affect gastric emptying. Neither a relation between postoperative gastric
emptying rate and weight loss nor between early satiety and weight loss was found. Therefore, it is unlikely that gastric
emptying plays a role in the mechanism of weight loss following laparoscopic adjustable gastric banding.
The authors disclose that there was no commercial interest and declare that there was no financial or material support. 相似文献
38.
39.
Petrov MS van Santvoort HC Besselink MG Cirkel GA Brink MA Gooszen HG 《The American journal of gastroenterology》2007,102(9):2079-2084
BACKGROUND: Oral refeeding in patients recovering from acute pancreatitis may cause pain relapse. Patients with pain relapse may be ill for prolonged periods, thereby consuming additional health care resources. We aimed to determine the incidence and risk factors of pain relapse on the basis of reviewing all studies on oral refeeding in acute pancreatitis. METHODS: Relevant literature cited in three electronic databases (Cochrane Central Register of Controlled Trials, EMBASE, and MEDLINE) as well as the abstracts of major gastroenterological meetings was reviewed. Outcome measures studied were the incidence of pain relapse and length of hospital stay. RESULTS: A total of three studies met the inclusion criteria. Sixty of 274 patients (21.9%) experienced pain relapse during the course of acute pancreatitis. In 47 of 60 (78.3%) patients pain relapse occurred within 48 h after commencement of oral refeeding. Two studies showed a significantly higher Balthazar's CT score on hospital admission in patients with pain relapse, whereas all three studies found no difference in the severity scores between patients with and without pain relapse. All three studies found a significant increase in the length of hospital stay in patients with pain relapse. CONCLUSIONS: The incidence of pain relapse after oral refeeding in acute pancreatitis is relatively high. Thereby, the quest for new therapeutical modalities that can prevent pain relapse is of current importance. 相似文献
40.
Doeksen A Gooszen JA van Duijvendijk P Tanis PJ Bakx R Slors JF van Lanschot JJ 《International journal of colorectal disease》2011,26(12):1549-1557