304 research outputs found
Pre-clinical evaluation of eight DOTA coupled gastrin-releasing peptide receptor (GRP-R) ligands for in vivo targeting of receptor-expressing tumors
Background: Overexpression of the gastrin-releasing peptide receptor (GRP-R) has been documented in several human neoplasms such as breast, prostate, and ovarian cancer. There is growing interest in developing radiolabeled peptide-based ligands toward these receptors for the purpose of in vivo imaging and radionuclide therapy of GRP-R-overexpressing tumors. A number of different peptide sequences, isotopes, and labeling methods have been proposed for this purpose. The aim of this work is to perform a direct side-by-side comparison of different GRP-R binding peptides utilizing a single labeling strategy to identify the most suitable peptide sequence. Methods: Solid-phase synthesis of eight derivatives (BN1-8) designed based on literature analysis was carried out. Peptides were coupled to the DOTA chelator through a PEG4 spacer at the N-terminus. Derivatives were characterized for serum stability, binding affinity on PC-3 human prostate cancer cells, biodistribution in tumor-bearing mice, and gamma camera imaging at 1, 6, and 24 h after injection. Results: Serum stability was quite variable among the different compounds with half-lives ranging from 16 to 400 min at 37 °C. All compounds tested showed Kd values in the nanomolar range with the exception of BN3 that showed no binding. Biodistribution and imaging studies carried out for compounds BN1, BN4, BN7, and BN8 showed targeting of the GRP-R-positive tumors and the pancreas. The BN8 compound (DOTA-PEG-DPhe-Gln-Trp-Ala-Val-NMeGly-His-Sta-Leu-NH2) showed high affinity, the longest serum stability, and the highest target-to-background ratios in biodistribution and imaging experiments among the compounds tested. Conclusions: Our results indicate that the NMeGly for Gly substitution and the Sta-Leu substitution at the C-terminus confer high serum stability while maintaining high receptor affinity, resulting in biodistribution properties that outperform those of the other peptides
Oral anticoagulant therapy at hospital admission associates with lower mortality in older COVID-19 patients with atrial fibrillation. An insight from the Covid Registry
FUNDING ACKNOWLEDGEMENTS: Type of funding sources: None. ONBEHALF: the GeroCovid Investigators Introduction. Atrial fibrillation (AF), the arrhythmia most frequently diagnosed in older patients, associates with serious, thrombo-embolic, complications and high mortality. COVID-19 severely affects aged subjects, determining an important prothrombotic status. Purpose. Aim of this study was to evaluate mortality-related factors in older AF patients with COVID-19. Methods. We included 806 in-hospital COVID-19 patients aged 60 years or more hospitalized between March 1st and June 6th 2020 and enrolled in a multicenter observational study. Results. The prevalence of AF was 21.8%. In-hospital mortality was higher in the AF group (36.9 vs. 27.5%; p = 0.015). Among AF patients, those who survived were younger (81 ± 8 vs. 84 ± 7 years; p = 0.002), had a lower CHA2DS2-VASc score (3.9 ± 1.6 vs. 4.4 ± 1.3; p = 0.02) and were more frequently treated with oral anticoagulants at admission (63.1 vs. 32.3%; p < 0.001) than those who died in hospital. At multivariable logistic regression analysis, lower age (p = 0.042), a better functional profile (p = 0.007), less severe COVID-19 manifestations at admission (p = 0.001), and the use of Vitamin K antagonists (OR = 0.16, 95%CI: 0.03-0.84; p = 0.031) or DOACs (OR = 0.22, 95%CI: 0.08-0.56; p = 0.002), compared to antiplatelet therapy or no treatment at all, were associated with a lower chance of in-hospital death. Conclusions. AF is a prevalent condition and a severity factor in older COVID-19 patients. Advanced age, dependency and severe clinical manifestations of disease characterized older AF subjects with a worse prognosis. Interestingly, pre-admission anticoagulant therapy correlated positively with in-hospital survival
Clinical and treatment features associated with improved 5-year survival rate in ALK-positive lung cancer treated with ALK-TKIs
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Lymphatic drainage mapping with indirect lymphography for canine mammary tumors
Mammary gland tumors are the most common canine neoplasms. They account for 25– 50% of all tumors diagnosed in bitches. Metastases and recurrences develop in about 35–70% of bitches following excision. The presence of regional lymph node metastases is a relevant factor affecting prognosis and treatment in cases of mammary gland tumors. The sentinel lymph node (SLN) is the first lymph node (or nodes) in the regional lymphatic basin that receives lymphatic flow from the primary neoplasm. The aim of this study is to investigate the SLN with indirect lymphography for a mammary tumor in dogs. The knowledge of the precise drainage pattern and SLN of the neoplastic mammary glands would provide clinically relevant information to the surgeon and to the oncologist, and it would be of high importance for the surgeon not only for performing the most adequate surgical excision but also for determining an accurate post-surgical prognosis
Cosmic ray tests of the D0 preshower detector
The D0 preshower detector consists of scintillator strips with embedded
wavelength-shifting fibers, and a readout using Visible Light Photon Counters.
The response to minimum ionizing particles has been tested with cosmic ray
muons. We report results on the gain calibration and light-yield distributions.
The spatial resolution is investigated taking into account the light sharing
between strips, the effects of multiple scattering and various systematic
uncertainties. The detection efficiency and noise contamination are also
investigated.Comment: 27 pages, 24 figures, submitted to NIM
Limits on WWgamma and WWZ Couplings from W Boson Pair Production
The results of a search for W boson pair production in pbar-p collisions at
sqrt{s}=1.8 TeV with subsequent decay to emu, ee, and mumu channels are
presented. Five candidate events are observed with an expected background of
3.1+-0.4 events for an integrated luminosity of approximately 97 pb^{-1}.
Limits on the anomalous couplings are obtained from a maximum likelihood fit of
the E_T spectra of the leptons in the candidate events. Assuming identical
WWgamma and WWZ couplings, the 95 % C.L. limits are -0.62<Delta_kappa<0.77
(lambda = 0) and -0.53<lambda<0.56 (Delta_kappa = 0) for a form factor scale
Lambda = 1.5 TeV.Comment: 10 pages, 1 figure, submitted to Physical Review
Influence of operative time and blood loss on surgical margins and functional outcomes for laparoscopic versus robotic-assisted radical prostatectomy: a prospective analysis
Introduction: The aim of this article was to analyze whether operative time and blood loss during radical prostatectomy (RP) can significantly influence surgical margins (SM) status and post-operative functional outcomes.
Material and methods: We prospectively analyzed prostate cancer (PC) patients undergoing RP, using robot-assisted (RARP) or laparoscopic (LRP) procedures. Blood loss was defined using the variation in hemoglobin (Hb, g/dl) values from the day before surgery and no later than 4 hours after surgery.
Results: From a whole population of 413 cases considered for RP, 67% underwent LRP and 33.0% RARP. Positive SM (SM+) were found in 33.9% of cases. Mean surgical operative time was 172.3 ±76 min (range 49-485), whereas blood loss was 2.3 ±1.2 g/dl (range 0.3-7.6). Operative time and blood loss at RP were not significantly correlated (r = -0.028275; p = 0.684). SM+ rates significantly (p = 0.002) varied by operative time; a higher SM+ rate was found in cases with an operative time <120 min (41.2%) and >240 min (53.4%). The risk of SM+ significantly increased 1.70 and 1.94 times in cases with an operative time <120 min and >240 min, respectively, independently to the surgical approach. The rate of erectile disfunction (ED) varied from 22.4% to 60.3% between <120 min and >240 min procedures (p = 0.001). According to blood loss, SM+ rates slightly but significantly (p = 0.032) varied; a higher rate of SM+ was found in cases with a Hb variation between 2-4 g/dl (35.9%).
Conclusions: Independently to the surgical approach, operative time, more than blood loss at RP, represents a significant variable able to influence SM status and post-operative ED
Search for R-parity Violating Supersymmetry in Dimuon and Four-Jets Channel
We present results of a search for R-parity-violating decay of the neutralino
chi_1^0, taken to be the Lightest Supersymmetric Particle. It is assumed that
this decay proceeds through one of the lepton-number violating couplings
lambda-prime_2jk (j=1,2; k=1,2,3). This search is based on 77.5 pb-1 of data,
collected by the D0 experiment at the Fermilab Tevatron in ppbar collisions at
a center of mass energy of 1.8 TeV in 1992-1995.Comment: 10 pages, 3 figure
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