288 research outputs found
Topical Flunixin Meglumine Effects on Pain Associated Biomarkers after Dehorning
Twenty-four calves were dehorned and treated with either topical flunixin meglumine formulated for systemic absorption or a placebo. Biomarkers associated with pain were evaluated for up to 72 hour after the dehorning procedure. Plasma cortisol concentrations, 90 minutes post-dehorning, and mechanical nociception threshold at the control site were the only tested biomarkers where a significant difference was demonstrated. No other differences of biomarkers between the two dehorned groups were observed for any time points. Although this product is easy to dose and dispense, its effects on pain biomarkers appears to be negligible
Excessive toxicity of cabozantinib in a phase II study in patients with recurrent and/or metastatic salivary gland cancer
AIM: Because the tyrosine kinases c-MET and vascular endothelial growth factor receptors (VEGFR) are often overexpressed in salivary gland cancer (SGC), this study evaluated the efficacy and safety of cabozantinib in patients with recurrent/metastatic (R/M) SGC. PATIENTS AND METHODS: A single-centre phase II study was conducted. Patients with immunohistochemical c-MET-positive R/M SGC were included in three cohorts: adenoid cystic carcinoma (ACC); salivary duct carcinoma (SDC) and other miscellaneous SGCs. No prior systemic treatments were required. Patients started cabozantinib 60 mg once daily. The primary outcome was the objective response rate (ORR). Secondary outcomes included survival, safety and quality of life. Per Simon-two-stage design, depending on efficacy, a maximum of 43 patients would be included. RESULTS: In total, 25 patients were included until premature closure owing to severe toxicity. Six patients (24%) had grade 3-5 wound complications, occurring at a median of 7.1 months on cabozantinib treatment (range 2.1-12.6). Remarkably, four of these six patients developed this complication in the area prior exposed to high-dose radiotherapy. Other grade ≥3 adverse events in >1 patient were hypertension (20%), diarrhoea (8%) and dehydration (8%). Twenty-one patients were evaluable for response; 1/15 ACC (ORR: 7%); 1/4 SDC and 0/2 patients with other miscellaneous SGC responded. Median progression-free survival was 9.4 months (95% confidence interval [CI] 7.4-11.4 months), 7.2 months (95%CI 0.0-15.1) and 6.9 months (95%CI 0.0-15.1), respectively. CONCLUSION: This study showed too many severe cabozantinib-associated wound complications in patients with SGC, especially in prior irradiated areas. Therefore, the study closed prematurely. The efficacy in the limited number of evaluable patients was low to moderate. TRIAL REGISTRATION: This trial was registered on ClinicalTrials.gov: NCT03729297
Allosteric control of Ubp6 and the proteasome via a bidirectional switch
The interplay of the proteasome and deubiquitinase Ubp6 is crucial for the degradation of ubiquitylated substrates. Here, the authors provide structural insights into the allosteric mechanism by which the activities of both Ubp6 and the proteasome are regulated. The proteasome recognizes ubiquitinated proteins and can also edit ubiquitin marks, allowing substrates to be rejected based on ubiquitin chain topology. In yeast, editing is mediated by deubiquitinating enzyme Ubp6. The proteasome activates Ubp6, whereas Ubp6 inhibits the proteasome through deubiquitination and a noncatalytic effect. Here, we report cryo-EM structures of the proteasome bound to Ubp6, based on which we identify mutants in Ubp6 and proteasome subunit Rpt1 that abrogate Ubp6 activation. The Ubp6 mutations define a conserved region that we term the ILR element. The ILR is found within the BL1 loop, which obstructs the catalytic groove in free Ubp6. Rpt1-ILR interaction opens the groove by rearranging not only BL1 but also a previously undescribed network of three interconnected active-site-blocking loops. Ubp6 activation and noncatalytic proteasome inhibition are linked in that they are eliminated by the same mutations. Ubp6 and ubiquitin together drive proteasomes into a unique conformation associated with proteasome inhibition. Thus, a multicomponent allosteric switch exerts simultaneous control over both Ubp6 and the proteasome
Imaging angiogenesis in patients with head and neck squamous cell carcinomas by [68Ga]Ga-DOTA-E-[c(RGDfK)]2 PET/CT
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Slater-Pauling Behavior of the Half-Ferromagnetic Full-Heusler Alloys
Using the full-potential screened Korringa-Kohn-Rostoker method we study the
full-Heusler alloys based on Co, Fe, Rh and Ru. We show that many of these
compounds show a half-metallic behavior, however in contrast to the
half-Heusler alloys the energy gap in the minority band is extremely small.
These full-Heusler compounds show a Slater-Pauling behavior and the total
spin-magnetic moment per unit cell (M_t) scales with the total number of
valence electrons (Z_t) following the rule: M_t=Z_t-24. We explain why the
spin-down band contains exactly 12 electrons using arguments based on the group
theory and show that this rule holds also for compounds with less than 24
valence electrons. Finally we discuss the deviations from this rule and the
differences compared to the half-Heusler alloys.Comment: 10 pages, 8 figures, revised figure 3, new text adde
89Zr-DFO-durvalumab PET/CT before durvalumab treatment in patients with recurrent or metastatic head and neck cancer
In this PD-L1 ImagiNg to prediCt durvalumab treatment response in SCCHN (PINCH) study, we performed 89Zr-DFO-durvalumab (anti- PD-L1 [programmed death ligand 1]) PET/CT in patients with recurrent or metastatic (R/M) squamous cell carcinoma of the head and neck (SCCHN) before monotherapy durvalumab treatment. The primary aims were to assess safety and feasibility of 89Zr-DFO-durvalumab PET imag-ing and predict disease control rate during durvalumab treatment. Sec-ondary aims were to correlate 89Zr-DFO-durvalumab uptake to tumor PD-L1 expression, 18F-FDG uptake, and treatment response of individ-ual lesions.Methods: In this prospective multicenter phase I-II study (NCT03829007), patients with incurable R/M SCCHN underwent base-line 18F-FDG PET and CT or MRI. Subsequently, PD-L1 PET imaging was performed 5 d after administration of 37 MBq of 89Zr-DFO-durvalumab. To optimize imaging conditions, dose finding was per-formed in the first 14 patients. For all patients (n = 33), durvalumab treatment (1,500 mg/4 wk, intravenously) was started within 1 wk after PD-L1 PET imaging and continued until disease progression or unacceptable toxicity (maximum, 24 mo). CT evaluation was assessed according to RECIST 1.1 every 8 wk. PD-L1 expression was deter-mined by combined positive score on (archival) tumor tissue. 89Zr-DFO-durvalumab uptake was measured in 18F-FDG-positive lesions, primary and secondary lymphoid organs, and blood pool.Results: In total, 33 patients with locoregional recurrent (n = 12) or metastatic SCCHN (n = 21) were enrolled. 89Zr-DFO-durvalumab injection was safe. A dose of 10 mg of durvalumab resulted in highest tumor-to-blood ratios. After a median follow-up of 12.6 mo, overall response rate was 26%. The disease control rate at 16 wk was 48%, with a mean duration of 7.8 mo (range, 1.7-21.1). On a patient level, 89Zr-DFO-durvalumab SUVpeak or tumor-to-blood ratio could not predict treatment response (hazard ratio, 1.5 [95% CI, 0.5-3.9; P = 0.45] and 1.3 [95% CI, 0.5-3.3; P = 0.60], respectively). Also, on a lesion level, 89Zr-DFO-durvalumab SUVpeak showed no substantial correlation to treatment response (Spearman p, 0.45; P = 0.051). Lesional 89Zr-DFO-durvalumab uptake did not correlate to PD-L1 combined positive score but did correlate to 18F-FDG SUVpeak (Spearman p, 0.391; P = 0.005).Conclusion: PINCH is the first, to our knowledge, PD-L1 PET/CT study in patients with R/M SCCHN and has shown the feasibility and safety of 89Zr-DFO-durvalumab PET/CT in a multicenter trial. 89Zr-DFO-durvalumab uptake did not correlate to durvalumab treat-ment response.Radiolog
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Cross-accent intelligibility of speech in noise: Long-term familiarity and short-term familiarization
Listeners must cope with a great deal of variability in the speech signal, and thus theories of speech perception must also account for variability, which comes from a number of sources, including variation between accents. It is well-known that there is a processing cost when listening to speech in an accent other than one’s own, but recent work has suggested that this cost is reduced when listening to a familiar accent widely represented in the media, and/or when short amounts of exposure to an accent are provided. Little is known, however, about how these factors (long-term familiarity and short-term familiarization with an accent) interact. The current study tested this interaction by playing listeners difficult-to-segment sentences in noise, before and after a familiarization period where the same sentences were heard in the clear, allowing us to manipulate short-term familiarization. Listeners were speakers of either Glasgow English or Standard Southern British English, and they listened to speech in either their own or the other accent, thereby allowing us to manipulate long-term familiarity. Results suggest that both long-term familiarity and short-term familiarization mitigate the perceptual processing costs of listening to an accent that is not one’s own, but seem not to compensate for them entirely, even when the accent is widely heard in the media
Half-metallicity and Slater-Pauling behavior in the ferromagnetic Heusler alloys
Introductory chapter for the book "Halfmetallic Alloys - Fundamentals and
Applications" to be published in the series Springer Lecture Notes on Physics,
P. H. Dederichs and I. Galanakis (eds). It contains a review of the theoretical
work on the half-metallic Heusler alloys.Comment: Introductory chapter for the book "Halfmetallic Alloys - Fundamentals
and Applications" to be published in the series Springer Lecture Notes on
Physics, P. H. Dederichs and I. Galanakis (eds
[F-18]FDG-PET/CT to prevent futile surgery in indeterminate thyroid nodules: a blinded, randomised controlled multicentre trial
Purpose To assess the impact of an [F-18]FDG-PET/CT-driven diagnostic workup to rule out malignancy, avoid futile diagnostic surgeries, and improve patient outcomes in thyroid nodules with indeterminate cytology.Methods In this double-blinded, randomised controlled multicentre trial, 132 adult euthyroid patients with scheduled diagnostic surgery for a Bethesda III or IV thyroid nodule underwent [F-18]FDG-PET/CT and were randomised to an [F-18] FDG-PET/CT-driven or diagnostic surgery group. In the [F-18]FDG-PET/CT-driven group, management was based on the [F-18]FDG-PET/CT result: when the index nodule was visually [F-18]FDG-positive, diagnostic surgery was advised; when [F-18]FDG-negative, active surveillance was recommended. The nodule was presumed benign when it remained unchanged on ultrasound surveillance. In the diagnostic surgery group, all patients were advised to proceed to the scheduled surgery, according to current guidelines. The primary outcome was the fraction of unbeneficial patient management in one year, i.e., diagnostic surgery for benign nodules and active surveillance for malignant/borderline nodules. Intention-to-treat analysis was performed. Subgroup analyses were performed for non-Hurthle cell and Hurthle cell nodules.Results Patient management was unbeneficial in 42% (38/91 [95% confidence interval [CI], 32-53%]) of patients in the [F-18] FDG-PET/CT-driven group, as compared to 83% (34/41 [95% CI, 68-93%]) in the diagnostic surgery group (p < 0.001). [F-18]FDG-PET/CT-driven management avoided 40% (25/63 [95% CI, 28-53%]) diagnostic surgeries for benign nodules: 48% (23/48 [95% CI, 33-63%]) in non-Hurthle cell and 13% (2/15 [95% CI, 2-40%]) in I-Liable cell nodules (p = 0.02). No malignant or borderline tumours were observed in patients under surveillance. Sensitivity, specificity, negative and positive predictive value, and benign call rate (95% CI) of [F-18]FDG-PET/CT were 94.1% (80.3-99.3%), 39.8% (30.0-50.2%), 95.1% (83.5-99.4%), 35.2% (25.4-45.9%), and 31.1% (23.3-39.7%), respectively.Conclusion An [F-18]FDG-PET/CT-driven diagnostic workup of indeterminate thyroid nodules leads to practice changing management, accurately and oncologically safely reducing futile surgeries by 40%. For optimal therapeutic yield, application should be limited to non-Hurthle cell nodules.Imaging- and therapeutic targets in neoplastic and musculoskeletal inflammatory diseas
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