2,699 research outputs found
THERMAL STABILITY AND EXTRA-STRENGTH OF AN ULTRAFINE GRAINED STAINLESS STEEL PRODUCED BY HIGH PRESSURE TORSION
International audienceInvestigations of an ultrafine-grained (UFG) Cr-Ni austenitic stainless steel produced by high pressure torsion (HPT) at room and elevated (400 C) temperatures followed by series of annealing up to 700 C are reported. The grain size of the alloy processed at room temperature (55 nm) was found to be about twice lower than the grain size of the alloy (90 nm) processed at elevated temperature. Besides, both as-processed states demonstrated a very high value of microhardness (~590 Hv) , while the steel in initial quenched state had the microhardness about 155 Hv. It is shown that the hardness of the steel in both UFG states does not decrease with annealing up to 650 C, and even a certain increase in hardness was observed for the steel produced at room temperature. At higher temperature (700 C), the recrystallization starts, and precipitation was observed
Dephosphorylated-uncarboxylated Matrix Gla protein concentration is predictive of vitamin K status and is correlated with vascular calcification in a cohort of hemodialysis patients.
Background: Matrix Gla protein (MGP) is known to act as a potent local inhibitor of vascular calcifications.
However, in order to be active, MGP must be phosphorylated and carboxylated, with this last process being
dependent on vitamin K. The present study focused on the inactive form of MGP (dephosphorylated and
uncarboxylated: dp-ucMGP) in a population of hemodialyzed (HD) patients. Results found in subjects being treated
or not with vitamin K antagonist (VKA) were compared and the relationship between dp-ucMGP levels and the
vascular calcification score were assessed.
Methods: One hundred sixty prevalent HD patients were enrolled into this observational cohort study, including
23 who were receiving VKA treatment. The calcification score was determined (using the Kauppila method) and
dp-ucMGP levels were measured using the automated iSYS method.
Results: dp-ucMGP levels were much higher in patients being treated with VKA and little overlap was found with
those not being treated (5604 [3758; 7836] vs. 1939 [1419; 2841] pmol/L, p <0.0001). In multivariate analysis,
treatment with VKA was the most important variable explaining variation in dp-ucMGP levels even when adjusting
for all other significant variables. In the 137 untreated patients, dp-ucMGP levels were significantly (p < 0.05) associated
both in the uni- and multivariate analysis with age, body mass index, plasma levels of albumin, C-reactive protein, and
FGF-23, and the vascular calcification score.
Conclusion: We confirmed that the concentration of dp-ucMGP was higher in HD patients being treated with VKA. We
observed a significant correlation between dp-ucMGP concentration and the calcification score. Our data support the
theoretical role of MGP in the development of vascular calcifications. We confirmed the potential role of the inactive
form of MGP in assessing the vitamin K status of the HD patients
Impact of Ureteral Stent Material on Stent-related Symptoms: A Systematic Review of the Literature
CONTEXT
Ureteral stents are essential implants that are used on a daily basis. Since their invention, advances in stent design have been directed towards alleviating stent-related symptoms. It remains unclear how the material composition of the stent affects stent-related symptoms.
OBJECTIVE
To review the literature and define the clinical impact of ureteral stent material on stent-related symptoms.
EVIDENCE ACQUISITION
A literature search of the Embase, MEDLINE (PubMed), and Web of Science databases was conducted on December 17, 2021 to collect articles comparing stent composition materials regarding stent-related symptoms. Thirteen publications met the inclusion criteria, of which only one met the high-quality requirements of the Cochrane Collaboration tool for assessing the risk of bias in randomized trials.
EVIDENCE SYNTHESIS
Most trials, including the highest quality trial, seem to support that silicone double-J (DJ) stents reduce stent-related symptoms compared to nonsilicone DJ stents. Regarding physical properties, it seems that "soft" or "flexible" DJ stents reduce stent-related symptoms. However, since there was only one high-quality study with a low risk of bias, it is impossible to draw a definitive conclusion owing to the lack of quality data.
CONCLUSIONS
Silicone DJ stents, and by extension "soft" DJ stents, appear to reduce stent-related symptoms compared to nonsilicone polymers and "hard" DJ stents. No definitive conclusion can be drawn owing to a lack of quality evidence. Creating a standard for measuring and reporting physical stent properties should be the first step for further research.
PATIENT SUMMARY
A ureteral stent is a small hollow tube placed inside the ureter to help urine drain from the kidney. We reviewed the literature on the impact of stent material on stent-related symptoms. We found that silicone may reduce stent-related symptoms, but no definitive conclusion can be drawn and further studies are needed
Lettres d'un militaire sur les changemens qui s'annoncent dans le systeme politique de l'Europe
La BNF atribuye la obra a Ricard, N. X. y COPAC a Etienne Pierre Silvestre RicardSign.: [ ]1, A-L4, M
Observation of the e/3 Fractionally Charged Laughlin Quasiparticles
The existence of fractional charges carrying the current is experimentally
demonstrated. Using a 2-D electron system in high magnetic field, we measure
the shot noise associated with tunneling in the fractional quantum Hall regime
at Landau level filling factor 1/3. The noise gives a direct determination of
the quasiparticle charge, which is found to be e*=e/3 as predicted by Laughlin.
The existence of e/3 Laughlin quasiparticles is unambiguously confirmed by the
shot noise to Johnson-Nyquist noise cross-over found for temperature e*V/2k.Comment: 4 pages, 4 figures, to appear in Phys. Rev. Lett. (accepted August
22
Prostate cancer detection rate in men undergoing transperineal template-guided saturation and targeted prostate biopsy
OBJECTIVES
To compare prostate cancer (PCa) detection rate of transperineal template-guided saturation prostate biopsy (SBx) and multiparametric magnetic resonance imaging (mpMRI)/transrectal ultrasound fusion guided targeted biopsy (TBx). MATERIALS AND METHODS: We prospectively enrolled 392 men who underwent SBx and TBx in case of suspicious lesions from November 2016 to October 2019. Triggers for a biopsy were an elevated prostate-specific antigen (PSA) and/or positive digital rectal examination and only treatment naïve patients without a previous diagnosis of PCa were included. Study inclusion occurred before biopsy and a prebiopsy mpMRI was available in all men. SBx were taken from 20 different locations according to the modified Barzell zones. The primary endpoint was the detection rate of clinically significant PCa (csPCa) and insignificant PCa (ciPCa) by SBx and/or TBx by comparing the two methods alone and in combination. Additional TBx were taken for any prostate imaging-reporting and data system (PI-RADS) lesion ≥3 seen on the mpMRI. csPCa was defined as any Gleason score ≥7 and ciPCa as Gleason score 6.
RESULTS
A total of 392 men with a median age of 64 years (interquartile range [IQR]: 58-69), a median PSA of 7.0 ng/ml (IQR: 4.8-10.1) were enrolled. Overall, PCa was found in 200 (51%) of all biopsied men, with 158 (79%) being csPCa and 42 (21%) ciPCa. A total of 268 (68%) men with a suspicious mpMRI and underwent a combined TBx and SBx, of whom csPCa was found in 139 (52%). In this subgroup, 116/139 (83%) csPCa would have been detected by TBx alone, and an additional 23 (17%) were found by SBx. Men with a negative mpMRI (PI-RADS < 3, n = 124, 32%) were found to have csPCa in 19 (15%) cases. In patients with a negative mpMRI in combination with a PSA density <0.1 ng/ml , only 8% (3/36) had csPCa. If only TBx would have been performed and all men with a negative mpMRI would not have been biopsed, 42/158 (27%) of csPCa would have been missed, and 38/42 (90%) ciPCa would have not been detected. On multivariable analysis, significant predictors of csPCa were increasing PSA (odds ratio, OR: 1.07 [95% confidence interval, CI: 1.03-1.11]), increasing age (OR: 1.07 [95% CI: 1.03-1.11]), PI-RADS score ≥ 3 (OR: 6.49 [95% CI: 3.55-11.89]), and smaller prostate volume (OR: 0.96 [95% CI: 0.95 -0.97] (p < 0.05 for all parameters).
CONCLUSION
In comparison to SBx, TBx alone detects csPCa in only ¾ of all men with a positive mpMRI lesion. Thus, systematic biopsies in addition to TBx have to be considered at least in some who undergo a prostate biopsy. In men with a negative mpMRI, SBx still detects 15% csPCa, but similarly overdetecting ciPCa. According to our results, low PSA density and negative mpMRI findings could be used to decide which men can safely avoid biopsy
A multifactorial approach including tumoural epidermal growth factor receptor, p53, thymidylate synthase and dihydropyrimidine dehydrogenase to predict treatment outcome in head and neck cancer patients receiving 5-fluorouracil
The prognostic value of tumoural epidermal growth factor receptor (EGFR), p53, thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) was analysed on 82 advanced head and neck cancer patients (71 men, 11 women; mean age 59). Induction treatment was cisplatin–5-FU ± folinic acid (61 patients, Chem group) or concomitant cisplatin–5-FU–radiotherapy (21 patients, RChem group). EGFR (binding assay), p53 protein (Sangtec immunoluminometric assay), TS and DPD activities (radioenzymatic assays) were measured on biopsies obtained at time of diagnosis. Significant positive correlation was demonstrated between p53 and EGFR. In the RChem group, p53 was higher in non-complete responders (median 1.03 ng mg−1) than in complete responders (median 0.08 ng mg−1) (P = 0.057). Univariate Cox analyses stratified on treatment group showed that specific survival (33 events) was significantly related to T staging, p53 taken as continuous or categorial (below vs over 0.80 ng mg−1) variable, and EGFR (below vs over 220 fmol mg−1); survival increased when EGFR and p53 were below thresholds. Multivariate stepwise analysis including T staging, EGFR and p53 revealed that T staging and EGFR were independent predictors of survival; relative risks were 3.68 for T staging and 2.65 for EGFR. Overall, EGFR remained an independent prognostic factor when response to treatment and T staging were considered in the multivariate analysis. © 1999 Cancer Research Campaig
An aPKC-Exocyst Complex Controls Paxillin Phosphorylation and Migration through Localised JNK1 Activation
The exocyst/aPKC complex controls the spatiotemporal activation of the kinases JNK and ERK at the leading edge of migrating cells and thereby controls the dynamic behaviour of the adhesion protein paxillin during cell migration
- …