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81.
Persistence of the underlying malignancy remains the major obstacle limiting the success of high-dose chemoradiotherapy with allogeneic bone marrow transplantation (BMT) for lymphomas and multiple myeloma. We used the C3H 38C13 murine B-cell lymphoma, which expresses and secretes clonally derived Ig, the idiotype of which can serve as a tumor-specific antigen, to test the principle of transfer of tumor idiotype-specific immunity with BM. BALB/c marrow donors were twice immunized with 38C13-derived Ig, or with an isotype-matched control Ig, conjugated to keyhole limpet hemocyanin. Lethally irradiated C3H recipients reconstituted with marrow from idiotype immune, but not nonspecifically immune, donors demonstrated protection against subsequent lethal tumor challenge. The immunoprotective effect of immune allogeneic marrow was abrogated by T-cell depletion of the marrow graft before infusion. Low levels of serum anti-idiotypic antibody remained unaltered in recipients of T-cell-depleted immune marrow, consistent with a primary role for T-cell immunity in the cellular mechanism of this phenomenon. A modest therapeutic effect of immune allogeneic marrow was observed against 10 day, 1 cm established subcutaneous tumors, but only in combination with a booster immunization of the recipient post-BMT. These results provide the rationale for a novel strategy for enhancing the specific antitumor effect of allogeneic marrow grafts. 相似文献
82.
Clay WF Bartels PG Katterman FR 《Proceedings of the National Academy of Sciences of the United States of America》1976,73(9):3220-3223
The mechanism of nuclear DNA replication in radicles of germinating cotton (Gossypium barbadense) was investigated. Pulse-labeling with [3H]thymidine indicates that replication intermediates are of small molecular weight (4-10S) and behave as if single-stranded. Prolonged labeling indicates that intermediates are of discrete size, suggesting a mechanism of discontinuous replication. Electron microscopy of nuclear DNA demonstrates a complex architecture which may include “eye forms” and “forks” similar to those reported in prokaryotes and animal systems. The possible universality of DNA replication mechanisms is discussed. 相似文献
83.
John-Paul Kilday Ute Katharina Bartels Eric Bouffet 《Current neurology and neuroscience reports》2014,14(4):1-9
Collectively, pediatric low-grade gliomas account for most brain tumors reported in children. Surgery is typically curable for operable lesions. However, more effective therapies are required for inaccessible tumors, both to overcome refractory disease and to minimize the toxicity associated with conventional adjuvant chemotherapy and radiotherapy regimens. Recent years have witnessed rapid improvements in our understanding of the molecular pathogenesis of several childhood tumors, including low-grade gliomas. As a result, several novel compounds targeting and inhibiting critical components of molecular signaling pathways purported to be overactive in the disease have been developed. This article summarizes the most recent literature evaluating such novel targeted agents in childhood low-grade gliomas. 相似文献
84.
Wilawan Thirapatarapong Hilary F. Armstrong Matthew N. Bartels 《Heart & lung : the journal of critical care》2014
Background
Coronary artery disease (CAD) is a common concomitant condition and an important cause of morbidity and mortality in patients with chronic obstructive pulmonary disease (COPD). Since COPD and CAD can both independently cause reduced exercise capacity, it is reasonable to hypothesize that the combination of these diseases may compound the abnormalities observed during cardiopulmonary exercise testing (CPET). However, little is known about the impact of CAD on the CPET response in COPD patients. The aim of this study is to compare exercise capacity and gas exchange variables in COPD patients with and without CAD.Methods
Fifty-four COPD subjects without CAD (COPDnoCAD) were matched to 54 COPD subjects diagnosed with CAD (COPD/CAD) according to age, gender, body mass index and severity of COPD. All subjects underwent resting pulmonary function and symptom-limited CPET.Results
Comparing COPDnoCAD patients with COPD/CAD patients revealed that exercise capacity, as measured by % peak oxygen consumption (42 ± 16% vs 53 ± 19%, p = 0.002) and % peak wattage (23 ± 13% vs 32 ± 16%, p = 0.001), was significantly lower in COPD/CAD. Ventilatory response, as measured by VE/VCO2 nadir (36 ± 9 vs 32 ± 5, p = 0.001), was significantly higher in COPD/CAD, with % peak VO2 and VE/VCO2 nadir correlating to % FEV1 and inversely correlating with %DLCO.Conclusion
COPD patients with CAD have significantly impaired CPET responses with lower exercise capacity and impaired gas exchange compared to COPD patients without CAD. These findings may affect the clinical interpretation of CPET data in COPD patients who have concomitant CAD. 相似文献85.
C. Lübbert D. Becker-Rux A. C. Rodloff S. Laudi T. Busch M. Bartels U. X. Kaisers 《Infection》2014,42(2):309-316
Purpose
From mid-2010 to early 2013 there was a large single-center (Leipzig University Hospital, Germany) outbreak of Klebsiella pneumoniae carbapenemase (KPC) type 2 producing K. pneumoniae (KPC-2-KP) involving a total of 103 patients. The aim of this study was to compare KPC-positive liver transplant recipients (LTR) and KPC-negative controls to determine both the relative risk of infection following colonization with KPC-2-KP and the case fatality rate associated with KPC-2-KP.Methods
The study cohort of this retrospective observational study comprised nine patients who had undergone orthotopic liver transplantation (LTx) (median age of 52 years, range 28–73 years) with confirmed evidence of colonization with KPC-2-KP. The data from these nine LTR were matched to 18 LTR (1:2) in whom carbapenem-resistant pathogens were not present and compared for clinical outcomes.Results
Of these nine cases, eight (89 %) progressed to infection due to KPC-2-KP, and five (56 %) were confirmed to have bloodstream infection with KPC-2-KP. Matched-pair analysis of KPC-positive LTR and KPC-negative controls revealed a substantially increased relative risk of 7.0 (95 % confidence interval 1.8–27.1) for fatal infection with KPC-2-producing K. pneumoniae after transplantation with a mortality rate of 78 % (vs. 11 %, p = 0.001).Conclusions
Colonization with KPC-2-KP in LTR leads to high infection rates and excess mortality. Therefore, frequent screening for carbapenem-resistant bacteria in patients on LTx waiting lists appears to be mandatory in an outbreak setting. Patients with evidence of persistent colonization with KPC-producing pathogens should be evaluated with extreme caution for LTx. 相似文献86.
87.
Torben K. Becker MD Bhakti Hansoti MBChB MPH Susan Bartels MD MPH Mark Bisanzo MD Gabrielle A. Jacquet MD MPH Kevin Lunney MD PhD Regan Marsh MD MPH Maxwell Osei‐Ampofo MBChB MBA MPH Indi Trehan MD MPH Christopher Lam BA Adam C. Levine MD MPH the Global Emergency Medicine Literature Review Group 《Academic emergency medicine》2016,23(10):1183-1191
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90.
Eva Freier Cora Stefanie Weber Ulrike Nowottne Christiane Horn Katrin Bartels Sabrina Meyer York Hildebrandt Tim Luetkens Yanran Cao Caroline Pabst Julia Muzzulini Benjamin Schnee Monika Christine Brunner-Weinzierl Maurizio Marangolo Carsten Bokemeyer Hans-Christian Deter Djordje Atanackovic 《Psychoneuroendocrinology》2010