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61.
62.
Wolfram Brugger Rainer Birken Hartmut Bertz Thomas Hecht Klaus Pressler† Jürgen Frisch‡ Gregor Schulz‡ Roland Mertelsmann Lothar Kanz 《British journal of haematology》1993,84(3):402-407
Summary. We report on the chemotherapy plus granulocyte colony-stimulating factor (G-CSF) induced mobilization of peripheral blood progenitor cells (PBPCs) and their impact on haematopoietic recovery following high-dose chemotherapy. Twenty-four patients with advanced solid tumours or lymphomas received standard-dose chemotherapy with VP16, ifosfamide and cisplatin (VIP) followed by filgrastim (G-CSF; 5 μg/kg s.c. daily for 14 d) for the prevention of chemotherapy induced neutropenia and for the simultaneous mobilization of PBPCs. Maximal numbers of progenitors of different lineages were reached at day 11 (range 9–14) after VIP chemotherapy. A median of 0·415 × 109/1 CD34+ cells (range 0·11–1·98), 9000 CFU-GM/ml (range 2800–17700). 3500 BFU-E/ml (range 400–10800) and 200 CFU-GEMM/ml (range 0–4400) were recruited. One single apheresis yielded a median of 1·6 × 108 mononuclear cells/kg (range 0·2–5·4) or 5·4 × 106 CD34+ cells/kg body weight (range 0·2–24·2). Fourteen patients who showed at least a partial remission after two cycles of the standard-dose chemotherapy regimen were subjected to high-dose VIP chemotherapy (cumulative doses of 1500 mg/m2 VP16, 12 g/m2 ifosfamide and 150 mg/m2 cisplatin) with or without PBPC support. The first six patients were treated with growth factors only (IL-3/GM-CSF) and did not receive PBPCs, whereas the following eight patients were supported with PBPCs in addition to IL-3 and GM-CSF. Neutrophil recovery as well as platelet recovery were significantly faster in patients receiving PBPCs with a median of 6·5 d below 0·1 × 109 neutrophils/1 and 3 d below 20 × 109 platelets/1 as compared to 10·5 d and 8 d in control patients receiving growth factors only. The accelerated platelet recovery in patients supported with PBPCs might be explained—in the absence of detectable colony-forming units megakaryocyte—by the presence of glycoprotein IIb/IIIa+, non-proliferating endomitotic megakaryocytic precursor cells within G-CSF mobilized PBPCs. Our data demonstrate that chemotherapy plus G-CSF mobilized PBPCs accelerate both neutrophil and platelet recovery after high-dose VIP chemotherapy in patients with solid tumours or lymphomas. 相似文献
63.
Jacob E. Resch Cathleen N. Brown Stephen N. Macciocchi C. Munro Cullum Damond Blueitt Michael S. Ferrara 《Journal of Athletic Training》2015,50(12):1292-1298
ContextSymptom presentation and recovery after sport concussion (SC) are variable. Empirically based models documenting typical symptom duration would assist health care providers in managing return to play after SC.ObjectiveTo develop a prediction model for SC symptom duration.DesignCross-sectional study.SettingTwo National Collegiate Athletic Association Division I university laboratories.Intervention(s)Participants completed the Revised Head Injury Scale (HIS-r), Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT), and Sensory Organization Test within 24 hours of SC diagnosis.ResultsThe final formula consisted of the HIS-r''s self-reported neck pain, drowsiness, tingling, and nervousness duration and ImPACT total symptom severity (R = 0.62, R2 = 39%, R2adj = 34.2%, P < .001). Approximately 29% (R2cv = 29%) of the variance associated with total days symptomatic after SC was explained by our preliminary formula when cross-validated. The current formula correctly identified 76% of participants who recovered within 10 days of injury.ConclusionsOur results suggest that self-reported duration of 4 symptoms during the initial 24 hours after injury along with total symptom severity as measured by ImPACT accounted for a considerable amount of variance associated with days symptomatic after SC in collegiate athletes. Until the formula is cross-validated in a college-aged sample, caution is warranted in using it clinically.Key Words: traumatic brain injuries, prediction, prolonged recovery, symptom severity, symptom duration
Key Points
- A formula to predict symptom resolution after sport concussion primarily consisting of initial symptom duration and severity correctly identified 76% of National Collegiate Athletic Association Division I collegiate athletes who recovered within 10 days.
- Before it can be used clinically, the formula must be cross-validated on larger samples.
64.
Khanlian Chung Lothar R. Schad Frank G. Zöllner 《International journal of computer assisted radiology and surgery》2018,13(10):1481-1495
Purpose
Cone beam computed tomography (CBCT) systems offer physicians crucial 3D and 2D imaging capabilities during interventions. However, certain medical applications only require very specific information from the CBCTs (e.g., determination of the position of high-contrast objects). In diagnostics, tomosynthesis techniques can be used in these cases to minimize dose exposure. Therefore, integrating such techniques on CBCT systems could also be beneficial for interventions. In this paper, we investigate the performance of our implementation of circular tomosynthesis on a CBCT device.Methods
The tomosynthesis scan trajectory is realized with step-and-shoot on a clinical C-arm device. The online calibration algorithm uses conventionally acquired 3D CBCT of the scanned object as prior knowledge to correct the imaging geometries. The online calibration algorithm was compared to an offline calibration to test its performance. A ball bearing phantom was used to evaluate the reconstructions with respect to geometric distortions. The evaluation was done for three different scenarios to test the robustness of our tomosynthesis implementation against object deviations (e.g., pen) and different object positioning.Results
The circular tomosynthesis was tested on a ball bearing and an anthropomorphic phantom. The results show that the calibration is robust against isocenter shifts and object deviations in the CBCT. All reconstructions used 100 projections and displayed limited angle artifacts. The accuracy of the positions and shapes of high-contrast objects were, however, determined precisely. (The maximal center position deviation is 0.31 mm.)Conclusion
For medical procedures that primarily determine the precise position of high-contrast objects, circular tomosynthesis could offer an approach to reduce dose exposure.65.
66.
Dehmer C Greinwald R Löffler J Grotz W Wolf L Hagmann HB Schneider W Kreisel W;German Salofalk Study Group 《International journal of colorectal disease》2003,18(5):406-412
BACKGROUND AND AIMS: Elevated levels of renal tubular markers in the urine are found in 20-30% of patients with chronic inflammatory bowel diseases. We investigated whether this reflects a dose-dependent tubulotoxicity of 5-aminosalicylic acid (5-ASA). PATIENTS AND METHODS: In an open, prospective, multicenter study 18 patients with Crohn's disease and 29 with ulcerative colitis were treated with 3 g 5-ASA or more daily as the sole drug for 6 weeks. Clinical activity (CDAI, CAI) and renal tubular markers [beta-N-acetyl-D-glucosaminidase (beta-NAG) and other proteins in urine] were monitored. We examined whether the proportion of patients with elevated beta-NAG is more than 15% higher (absolute difference) than that prior to treatment. RESULTS: The proportion decreased from 19.2% to 12.8% in the intention-to-treat analysis (n=47) and from 24.3% to 13.5% in the per-protocol analysis (n=37), which was not more than 15% higher than at baseline. Mean CDAI decreased from 222 to 146 and mean CAI from 7.3 to 3.1 (intention-to-treat analysis). Response to therapy was shown by 61% of patients with Crohn's disease and 66% of patients with ulcerative colitis. The cumulative dose of 5-ASA was not correlated with beta-NAG level in the urine. CONCLUSION: This study largely rules out that 5-ASA at 3 g or higher per day for 6 weeks induces renal tubular damage. Elevated renal tubular markers reflect inflammatory activity or an extraintestinal manifestation of inflammatory bowel diseases. 相似文献
67.
Distribution of vesicular glutamate transporter-2 messenger ribonucleic Acid and protein in the septum-hypothalamus of the rat 总被引:6,自引:0,他引:6
The excitatory neurotransmitter glutamate is involved in the control of most, perhaps all, neuroendocrine systems, yet the sites of glutamatergic neurons and their processes are unknown. Here, we used in situ hybridization and immunohistochemistry for the neuron-specific vesicular glutamate transporter-2 (VGLUT2) to identify the neurons in female rats that synthesize the neurotransmitter glutamate as well as their projections throughout the septum-hypothalamus. The results show that glutamatergic neurons are present in the septum-diagonal band complex and throughout the hypothalamus. The preoptic area and ventromedial and dorsomedial nuclei are particularly rich in glutamatergic neurons, followed by the supraoptic, paraventricular, and arcuate nuclei, whereas the suprachiasmatic nucleus does not express detectable amounts of VGLUT2 mRNA. Immunoreactive neurites are seen in very high densities in all regions analyzed, particularly in the preoptic region, followed by the ventromedial, dorsomedial, and arcuate nuclei as well as the external layer of the median eminence, whereas the mammillary complex does not exhibit VGLUT2 immunoreactivity. Many VGLUT2 immunoreactive fibers also contained synaptophysin, suggesting that the transporter is indeed localized to presynaptic terminals. Together, the results identify glutamatergic cell bodies throughout the septum-hypothalamus in region-specific patterns and show that glutamatergic nerve terminals are present in very large numbers such that most neurons in these brain regions can receive glutamatergic input. We examined the GnRH system as an example of a typical neuroendocrine system and could show that the GnRH perikarya are closely apposed by many VGLUT2-immunoreactive boutons, some of which also contained synaptophysin. The presence of VGLUT2 mRNA-containing cells in specific nuclei of the hypothalamus indicates that many neuroendocrine neurons coexpress glutamate as neurotransmitter, in addition to neuropeptides. These systems include the oxytocin, vasopressin, or CRH neurons as well as many others in the periventricular and mediobasal hypothalamus. The presence of VGLUT2 mRNA in steroid-sensitive regions of the hypothalamus, such as the anteroventral periventricular, paraventricular, or ventromedial nuclei indicates that gonadal and adrenal steroid can directly alter the functions of these glutamatergic neurons. 相似文献
68.
Dr. H. Vogelsang P. Ferenci W. Woloszczuk H. Resch C. Herold S. Frotz A. Gangl 《Digestive diseases and sciences》1989,34(7):1094-1099
Vitamin D deficiency is frequently observed in patients with Crohn's disease and may be associated with an increased risk of development of metabolic bone disease. To estimate the incidence of metabolic bone disease by noninvasive methods, 31 patients (17–75 years old) with Crohn's disease and low 25-hydroxy vitamin D (25-OHD) levels in winter were investigated in the following summer by measuring the bone mineral content (BMC) of the distal radius by single photon absorptiometry and the cortical area ratio (CAR) calculated from radiographs of the right hand and by x-ray of the lumbar spine. Forty-five percent of the patients showed signs of metabolic bone disease. BMC and CAR correlated with 25-OHD serum levels (P<0.05), especially in men. Furthermore, the amount of sun exposure has an influence not only on 25-OHD serum levels both in summer and in winter (P=0.0006), but also on the BMC (P=0.07). Consequently, vitamin D deficiency is of major importance for the development of metabolic bone disease in patients with Crohn's disease. Vitamin D deficiency can be prevented by increasing sun exposure and long-term vitamin D supplementation. 相似文献
69.
Bethge WA Faul C Bornhäuser M Stuhler G Beelen DW Lang P Stelljes M Vogel W Hägele M Handgretinger R Kanz L 《Blood cells, molecules & diseases》2008,40(1):13-19
Haploidentical hematopoietic cell transplantation (HHCT) after high dose conditioning with CD34-selected stem cells has been complicated by high regimen related toxicities, slow engraftment and delayed immune reconstitution leading to increased treatment related mortality (TRM). A new regimen using reduced intensity conditioning (RIC) and graft CD3/CD19 depletion with anti-CD3 and anti-CD19 coated microbeads on a CliniMACS device may allow HHCT with lower toxicity and faster engraftment. CD3/CD19 depleted grafts not only contain CD34+ stem cells but also CD34 negative progenitors, natural killer, graft facilitating and dendritic cells. RIC was performed with fludarabine (150-200 mg/m(2)), thiotepa (10 mg/kg), melphalan (120 mg/m(2)) and OKT-3 (5 mg/day, day -5 to +14) and no posttransplant immunosuppression. Twenty nine patients (median age=42 (range, 21-59) years) have been transplanted with this regimen. Diagnosis were AML (n=16), ALL (n=7), NHL (n=3), MM (n=2) and CML (n=1). Patients were "high risk" with refractory disease or relapse after preceding HCT. The CD3/CD19 depleted haploidentical grafts contained a median of 7.6x10(6) (range, 3.4-17x10(6)) CD34+ cells/kg, 4.4x10(4) (range, 0.006-44x10(4)) CD3+ T cells/kg and 7.2x10(7) (range, 0.02-37.3x10(7)) CD56+ cells/kg. Donor-recipient KIR-ligand-mismatch was found in 19 of 29 patients. The regimen was well tolerated with maximum acute toxicity being grade 2-3 mucositis. Because of severe neurotoxicity in 4 patients treated with 200 mg/m(2) fludarabine, the dose was reduced to 150 mg/m(2). Engraftment was rapid with a median time to >500 granulocytes/microL of 12 (range, 10-21) days, >20,000 platelets/microL of 11 (range, 7-38) days and full donor chimerism after 2-4 weeks in all patients. Incidence of grade II-IV degrees GVHD was 48% with grade II degrees =10, III degrees =2 and IV degrees =2. One patient, who received the highest T-cell dose, developed lethal grade IV GVHD. TRM in the first 100 days was 6/29 (20%) with deaths due to idiopathic pneumonia syndrome (n=1), mucormycosis (n=1), pneumonia (n=3) or GVHD (n=1). Overall survival is 9/29 patients (31%) with deaths due to infections (n=7), GVHD (n=1) and relapse (n=12) with a median follow-up of 241 days (range, 112-1271). In conclusion, this regimen is promising in high risk patients lacking a suitable donor, and a prospective phase I/II study is ongoing. 相似文献
70.
Prof. Dr. Lothar Engelmann 《Intensivmedizin und Notfallmedizin》2008,45(5):255-262
The VISEP study was conducted in a randomized manner from April 2003 to June 2005 in 18 interdisciplinary intensive care units. Two questions were to be clarified: (1) Is the benefit of intensive insulin therapy reproducible in septic patients and (2) should crystalloids or colloids be used for initial fluid resuscitation in severe sepsis? A total of 2212 patients were screened, but only 600 patients were randomized into the four study groups. Intensive insulin therapy The blood glucose level was adjusted to be between 80 and 110 mg/dl in the intensive insulin therapy (IIT) group and between 180 and 200 mg/dl in the “conservative” insulin group (CIT). There were no significant differences in mortality at day 28 and day 90 (24.7 vs 26.0%; p = 0.74 and 39.7 vs 35.4%; p = 0.31, respectively). Indeed, the study had to be stopped because of safety reasons due to significantly more serious hypoglycemic states (17.0 vs 4.1%; p < 0.001) in the IIT group. Although the study does not refute the benefit of intensive insulin therapy, the results will contribute to the end of IIT in intensive care units. Colloids vs crystalloids A total of 600 patients were randomized, but only 262 patients were treated by 10% HES 200/0.5 and 303 by Ringer’s lactate (Sterofundin®). At day 28, the mortality was insignificantly increased in the HES group compared with the Ringer’s lactate group (26.7 vs 24.1%; p = 0.48). At day 90, a significantly increased mortality was observed in the HES group (26.7 vs 24.1%; p = 0.48). In addition, a significantly increased incidence of acute renal failure (34.9 vs 22.8%; p = 0.02) was seen and renal replacement therapy became necessary more frequently (18.3 vs 9.2%). For these reasons, the authors warn about the use of hydroxyethyl starch in severe sepsis and septic shock. The submitted data do not justify this warning. The daily maximal dose of 20 ml/ kg/d for 10% HES 200/0.5 was exceeded and the recommended upper serum creatinine level was elevated from 177 to 320 µmol/l. For patients treated with recommended daily dosage of 20 ml/kg/ d (22 mg/kg/d in the study), the mortality is comparable with Ringer’s lactate at days 28 and 90 (22.8 vs 24.1%; p = 0.747 and 30.9 vs 33.9%; p = 0.562, respectively). The study has shown that 10% HES 200/0.5 is a drug, for which the indication, contraindications and daily maximal dose have to be met. 相似文献