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61.
The Y-box binding protein YB-1 is associated with progressive disease and mediates survival and drug resistance in multiple myeloma 总被引:1,自引:0,他引:1
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Chatterjee M Rancso C Stühmer T Eckstein N Andrulis M Gerecke C Lorentz H Royer HD Bargou RC 《Blood》2008,111(7):3714-3722
Current knowledge about molecular mechanisms underlying disease progression and drug resistance in multiple myeloma (MM) is still limited. Here, we analyzed the potential pathogenetic role of the Y-box binding protein YB-1 in MM. YB-1 is a member of the cold-shock domain protein superfamily and involved in various cellular functions such as proliferation. Immunohistochemical analyses revealed that neither normal bone marrow (BM) plasma cells (PCs), premalignant PCs of patients with monoclonal gammopathy of unknown significance (MGUS), nor MM cells with a mature morphology showed expression of YB-1 in situ. In contrast, YB-1 was strongly expressed in situ in normal PC precursor blasts as well as in a MM subset and in vitro in all of the evaluated MM cell lines. The YB-1-expressing MM cells were characterized by an immature morphology and a highly proliferative phenotype as defined by Ki 67 expression. We observed that siRNA-mediated knockdown of YB-1 decreased proliferation and induced apoptosis in MM cells even in the presence of BM stromal cells. Furthermore, we found that overexpression of YB-1 mediated resistance toward doxorubicin-induced apoptosis in MM cells. Thus, YB-1 contributes to disease progression, survival, and drug resistance in MM and might therefore provide an attractive therapeutic target. 相似文献
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64.
Modafinil in the treatment of idiopathic hypersomnia without long sleep time—a randomized,double‐blind,placebo‐controlled study
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Geert Mayer Heike Benes Peter Young Marion Bitterlich Andrea Rodenbeck 《Journal of sleep research》2015,24(1):74-81
In 2010 the European Medicines Agency withdrew the indication of modafinil for the treatment of obstructive sleep apnea, shift work sleep disorder and for idiopathic hypersomnia (IH). In uncontrolled studies, modafinil has been reported to be efficacious in the treatment of sleep disorders. We therefore performed a randomized, placebo‐controlled study with the aim of proving the efficacy of modafinil treatment in these patients. Drug‐free IH patients without long sleep according to ICSD2 criteria, age >18 years and disease duration >2 years were included. After a washout phase, patients at baseline received placebo or 100 mg modafinil in the morning and at noon over 3 weeks, followed by 1 week without medication. At each visit the Epworth Sleepiness Scale (ESS) and Clinical Global Impression (CGI) rating scale were performed. At baseline and on days 8 and 21 four Maintenance of Wakefulness Tests (MWTs)/day or per day were performed. Patients kept a sleep–wake diary throughout the study. Between 2009 and 2011 three sleep centres recruited 33 participants. Compared to placebo, modafinil decreased sleepiness significantly and improved mean sleep latency in the MWT non‐significantly. The CGI improved significantly from baseline to the last visit on treatment. The most frequent adverse events were headaches and gastrointestinal disorders; skin and psychiatric reactions were not reported. The number of reported naps and duration of daytime sleepiness decreased significantly. Total sleep time of nocturnal sleep was slightly reduced. The sleep diaries showed increases in feeling refreshed in the morning; the diurnal diaries showed significant improvement of performance and of exhaustion. Modafinil is an effective and safe medication in the treatment of IH. Adverse events are mild to moderate. 相似文献
65.
Deformation strain is the main physical driver for skeletal precursors to undergo osteogenesis in earlier stages of osteogenic cell maturation
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Anna Finne‐Wistrand Melanie Krug Thomas Schwarz Franz Jakob Heike Walles Jan Hansmann 《Journal of tissue engineering and regenerative medicine》2018,12(3):e1474-e1479
Mesenchymal stem cells play a major role during bone remodelling and are thus of high interest for tissue engineering and regenerative medicine applications. Mechanical stimuli, that is, deformation strain and interstitial fluid‐flow‐induced shear stress, promote osteogenic lineage commitment. However, the predominant physical stimulus that drives early osteogenic cell maturation is not clearly identified. The evaluation of each stimulus is challenging, as deformation and fluid‐flow‐induced shear stress interdepend. In this study, we developed a bioreactor that was used to culture mesenchymal stem cells harbouring a strain‐responsive AP‐1 luciferase reporter construct, on porous scaffolds. In addition to the reporter, mineralization and vitality of the cells was investigated by alizarin red staining and 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide. Quantification of the expression of genes associated to bone regeneration and bone remodelling was used to confirm alizarin red measurements. Controlled perfusion and deformation of the 3‐dimensional scaffold facilitated the alteration of the expression of osteogenic markers, luciferase activity, and calcification. To isolate the specific impact of scaffold deformation, a computational model was developed to derive a perfusion flow profile that results in dynamic shear stress conditions present in periodically loaded scaffolds. In comparison to actually deformed scaffolds, a lower expression of all measured readout parameters indicated that deformation strain is the predominant stimulus for skeletal precursors to undergo osteogenesis in earlier stages of osteogenic cell maturation. 相似文献
66.
Fabio Vittadello Maria Mischo-Kelling Heike Wieser Luisa Cavada Lukas Lochner Carla Naletto 《Journal of interprofessional care》2018,32(3):266-273
This article presents a study that aimed to validate a translation of a multiple-group measurement scale for interprofessional collaboration (IPC). We used survey data gathered over a three month period as part of a mixed methods study that explored the nature of IPC in Northern Italy. Following a translation from English into Italian and German the survey was distributed online to over 5,000 health professionals (dieticians, nurses, occupational therapists, physicians, physiotherapists, speech therapists and psychologists) based in one regional health trust. In total, 2,238 different health professions completed the survey. Based on the original scale, three principal components were extracted and confirmed as relevant factors for IPC (communication, accommodation and isolation). A confirmatory analysis (3-factor model) was applied to the data of physicians and nurses by language group. In conclusion, the validation of the German and Italian IPC scale has provided an instrument of acceptable reliability and validity for the assessment of IPC involving physicians and nurses. 相似文献
67.
Maryam Aghighi Laura Pisani Ashok J. Theruvath Anne M. Muehe Jessica Donig Ramsha Khan Samantha J. Holdsworth Neeraja Kambham Waldo Concepcion Paul C. Grimm Heike E. Daldrup-Link 《Molecular imaging and biology》2018,20(1):139-149
Purpose
To evaluate whether ultrasmall superparamagnetic iron oxide nanoparticle (USPIO)-enhanced magnetic resonance imaging (MRI) can detect allograft rejection in pediatric kidney transplant patients.Procedures
The USPIO ferumoxytol has a long blood half-life and is phagocytosed by macrophages. In an IRB-approved single-center prospective clinical trial, 26 pediatric patients and adolescents (age 10–26 years) with acute allograft rejection (n = 5), non-rejecting allografts (n = 13), and normal native kidneys (n = 8) underwent multi-echo T2* fast spoiled gradient-echo (FSPGR) MRI after intravenous injection (p.i.) of 5 mg Fe/kg ferumoxytol. T2* relaxation times at 4 h p.i. (perfusion phase) and more than 20 h p.i. (macrophage phase) were compared with biopsy results. The presence of rejection was assessed using the Banff criteria, and the prevalence of macrophages on CD163 immunostains was determined based on a semi-quantitative scoring system. MRI and histology data were compared among patient groups using t tests, analysis of variance, and regression analyses with a significance threshold of p < 0.05.Results
At 4 h p.i., mean T2* values were 6.6 ± 1.5 ms for native kidneys and 3.9 ms for one allograft undergoing acute immune rejection. Surprisingly, at 20–24 h p.i., one rejecting allograft showed significantly prolonged T2* relaxation times (37.0 ms) compared to native kidneys (6.3 ± 1.7 ms) and non-rejecting allografts (7.6 ± 0.1 ms). Likewise, three additional rejecting allografts showed significantly prolonged T2* relaxation times compared to non-rejecting allografts at later post-contrast time points, 25–97 h p.i. (p = 0.008). Histological analysis revealed edema and compressed microvessels in biopsies of rejecting allografts. Allografts with and without rejection showed insignificant differences in macrophage content on histopathology (p = 0.44).Conclusion
After ferumoxytol administration, renal allografts undergoing acute rejection show prolonged T2* values compared to non-rejecting allografts. Since histology revealed no significant differences in macrophage content, the increasing T2* value is likely due to the combined effect of reduced perfusion and increased edema in rejecting allografts.68.
Nicole Rübsamen Stefanie Castell Johannes Horn André Karch J?rdis J. Ott Heike Raupach-Rosin Beate Zoch Gérard Krause Rafael T. Mikolajczyk 《Emerging infectious diseases》2015,21(6):1012-1018
Ebola virus disease (EVD) outbreaks have occurred during the past 5 decades, but none has affected European countries like the 2014 epidemic in West Africa. We used an online questionnaire to investigate risk perceptions in Germany during this epidemic peak. Our questionnaire covered risk perceptions, knowledge about transmission routes, media use, reactions to the outbreak, attitudes toward measures to prevent the spread of EVD and vaccination against EVD, and willingness to volunteer for aid missions. Of 974 participants, 29% indicated that they worried about EVD, 4% correctly stated virus transmission routes, and 75% incorrectly rated airborne transmission and transmission by asymptomatic patients as possible. Many indicated that if a patient were flown to Germany for treatment in a nearby hospital, they would adapt preventive behavior. Although most participants were not worried about EVD at the current stage of the epidemic, misperceptions regarding transmission were common and could trigger inappropriate behavior changes. 相似文献
69.
Moehler M Hoffmann T Hildner K Siebler J Galle PR Heike M 《Zeitschrift für Gastroenterologie》2002,40(12):957-964
Irinotecan (CPT-11), oxaliplatin (OXA) and different folinic acid(FA) modulated 5-fluorouracil (5-FU) regimens are active as first-and second-line chemotherapy of metastatic colorectal cancer. However, the best palliative sequence of these substances is still unclear. After CPT-11 containing regimens the optimal salvage protocol has not yet been defined. Here, we retrospectively analysed the weekly ambulant combination of OXA with continuous FA/5-FU (FUFOX) after two different CPT-11 containing chemotherapeutic regimens. PATIENTS: During October 1999 and May 2001, 20 patients (median 62; 48-74 years) were included who had disease progression after CPT-11 /bolus FA/5-FU (Saltz; 7 patients, group A) or after FA/5-FU followed by CPT-11 alone (13 patients, group B). OXA(60 mg/m2) was given for 2 hours prior to FA (500 mg/m2) as 2 h-infusion and continuous 5-FU (2.600 mg/m2) for 24 h-infusion on day 1,8,15 and 22 (repeated after week 6). RESULTS: FUFOX was administered 252 times. About 1,203 mg OXA per patient was given. Toxicities NC-CrC grade 3 were observed in 10 patients: diarrhoea (4), mucositis (5), nausea/vomiting (2), anaemia (1), leucopenia (1), thrombopenia (1) and hand-foot-syndrome (1), 3 patients showed minor remissions, II patients stable disease. The median time to progression was 16(0-39) weeks. The median survival from start of FUFOX and from start of any palliative therapy was 33 (5-65) and 99 (44-200) weeks for all patients, respectively. CONCLUSIONS: FUFOX was efficient for additional tumour control in 70% of patients pretreated with CPT-11/5-FU based regimens. Sequential palliative treatment can lead to prolonged survival. 相似文献
70.
Johannes E. A. Wolff Hans J. Galla Heike Poppenborg 《Journal of cancer research and clinical oncology》1998,124(8):409-414
In vitro cytotoxicity testing is used increasingly during the development of clinical treatment protocols. These tests are
influenced by many variables, not all of which have been assessed systematically yet. We analyzed the influence of the recovery
time between the end of treatments and measurements on the detection of cellular resistance. The development of resistance
to cisplatin and radiation was chosen as a model since the schedule of these treatments is the objective of several ongoing
clinical trials. C6 rat glioma, T98G, 86HG-39, A172 human glioma and TE671 human rhabdomyosarcoma cells were pretreated with
radiation or cisplatin. The cellular resistance was then compared in pretreated and wild-type cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium
bromide (MTT) test. In all cell lines, apparent drug concentrations killing 50% of the cells were dependent on the recovery
time. In A172 cells this concentration was 10.3 ± 02.1 μM after 48 h but decreased to 3.56 ± 0.44 μM after 120 h recovery
time (P < 0.001). After recovery times of more than 168 h, 53% of all pretreated cell lines were resistant to cisplatin or radiation,
25% were unchanged and 22% were more sensitive. However, only half the resistant cells could be identified when the MTT test
was done with only 48 h recovery time. The sensitivity of detection increased from 0.46 to 0.83 when the recovery time of
the test system was extended from 48 h to 168 h. The specificity was not dependent on the recovery time. Experi-ments showing
resistance after short recovery times are reliable, but lack of resistance can only be shown in experiments with long recovery
times. Cisplatin treatment can result in resistance to radiation in glioma cells.
Received: 7 March 1997 / Accepted: 18 March 1998 相似文献