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The present investigation addresses the mechanical properties, wear behaviour, and high-temperature oxidation of cermets and hardmetals based on either Ti(C,N) or WC and a metal binder based on Fe15Ni or Fe15Ni10Cr. This study also includes a commercial-grade WC-Co for comparative purposes. The production of these materials involved a powder metallurgy and sinter-HIP processing route under identical conditions. It is found that WC-based materials have superior mechanical properties, including hardness, fracture toughness, transversal rupture strength (TRS), and wear response, compared to Ti(C,N)-based materials. However, the latter show better oxidation behaviour than the former. Notably, WC-FeNi exhibits a higher hardness and TRS than the commercial-grade material (an increase of 7% and 9%, respectively). The difference in wear behaviour is due to the difference in wear mechanisms. In this regard, cermets wear through a tribolayer of Ti and Fe oxides, while hardmetals primarily wear through abrasion from ploughing. Thus, hardmetals exhibit a lower coefficient of friction (COF) and wear rate than cermets. Furthermore, Ti(C,N)-based materials form a protective layer of TiO 2 , which enhances their integrity and reduces mass gain. The addition of Cr to the FeNi binder only appears to have a clear effect on the TRS of the materials.

Aim: To present state of the art on the management of urinary stones from a panel of globally recognized urolithiasis experts who met during the Experts in Stone Disease Congress in Valencia in January 2024. Options of treatment: The surgical treatment modalities of renal and ureteral stones are well defined by the guidelines of international societies, although for some index cases more alternative options are possible. For 1.5 cm renal stones, both m-PCNL and RIRS have proven to be valid treatment alternatives with comparable stone-free rates. The m-PCNL has proven to be more cost effective and requires a shorter operative time, while the RIRS has demonstrated lower morbidity in terms of blood loss and shorter recovery times. SWL has proven to be less effective at least for lower calyceal stones but has the highest safety profile. For a 6mm obstructing stone of the pelviureteric junction (PUJ) stone, SWL should be the first choice for a stone less than 1 cm, due to less invasiveness and lower risk of complications although it has a lower stone free-rate. RIRS has advantages in certain conditions such as anticoagulant treatment, obesity, or body deformity. Technical issues of the surgical procedures for stone removal: In patients receiving antithrombotic therapy, SWL, PCN and open surgery are at elevated risk of hemorrhage or perinephric hematoma. URS, is associated with less morbidity in these cases. An individualized combined evaluation of risks of bleeding and thromboembolism should determine the perioperative thromboprophylactic strategy. Pre-interventional urine culture and antibiotic therapy are mandatory although UTI treatment is becoming more challenging due to increasing resistance to routinely applied antibiotics. The use of an intrarenal urine culture and stone culture is recommended to adapt antibiotic therapy in case of postoperative infectious complications. Measurements of temperature and pressure during RIRS are vital for ensuring patient safety and optimizing surgical outcomes although techniques of measurements and methods for data analysis are still to be refined. Ureteral stents were improved by the development of new biomaterials, new coatings, and new stent designs. Topics of current research are the development of drug eluting and bioresorbable stents. Complications of endoscopic treatment: PCNL is considered the most invasive surgical option. Fever and sepsis were observed in 11 and 0.5% and need for transfusion and embolization for bleeding in 7 and 0.4%. Major complications, as colonic, splenic, liver, gall bladder and bowel injuries are quite rare but are associated with significant morbidity. Ureteroscopy causes less complications, although some of them can be severe. They depend on high pressure in the urinary tract (sepsis or renal bleeding) or application of excessive force to the urinary tract (ureteral avulsion or stricture). Diagnostic work up:  Genetic testing consents the diagnosis of monogenetic conditions causing stones. It should be carried out in children and in selected adults. In adults, monogenetic diseases can be diagnosed by systematic genetic testing in no more than 4%, when cystinuria, APRT deficiency, and xanthinuria are excluded. A reliable stone analysis by infrared spectroscopy or X-ray diffraction is mandatory and should be associated to examination of the stone under a stereomicroscope. The analysis of digital images of stones by deep convolutional neural networks in dry laboratory or during endoscopic examination could allow the classification of stones based on their color and texture. Scanning electron microscopy (SEM) in association with energy dispersive spectrometry (EDS) is another fundamental research tool for the study of kidney stones. The combination of metagenomic analysis using Next Generation Sequencing (NGS) techniques and the enhanced quantitative urine culture (EQUC) protocol can be used to evaluate the urobiome of renal stone formers. Twenty-four hour urine analysis has a place during patient evaluation together with repeated measurements of urinary pH with a digital pH meter. Urinary supersaturation is the most comprehensive physicochemical risk factor employed in urolithiasis research. Urinary macromolecules can act as both promoters or inhibitors of stone formation depending on the chemical composition of urine in which they are operating. At the moment, there are no clinical applications of macromolecules in stone management or prophylaxis. Patients should be evaluated for the association with systemic pathologies., Prophylaxis: Personalized medicine and public health interventions are complementary to prevent stone recurrence. Personalized medicine addresses a small part of stone patients with a high risk of recurrence and systemic complications requiring specific dietary and pharmacological treatment to prevent stone recurrence and complications of associated systemic diseases. The more numerous subjects who form one or a few stones during their entire lifespan should be treated by modifications of diet and lifestyle. Primary prevention by public health interventions is advisable to reduce prevalence of stones in the general population. Renal stone formers at "high-risk" for recurrence need early diagnosis to start specific treatment. Stone analysis allows the identification of most "high-risk" patients forming non-calcium stones: infection stones (struvite), uric acid and urates, cystine and other rare stones (dihydroxyadenine, xanthine). Patients at "high-risk" forming calcium stones require a more difficult diagnosis by clinical and laboratory evaluation. Particularly, patients with cystinuria and primary hyperoxaluria should be actively searched., Future Research: Application of Artificial Intelligence are promising for automated identification of ureteral stones on CT imaging, prediction of stone composition and 24-hour urinary risk factors by demographics and clinical parameters, assessment of stone composition by evaluation of endoscopic images and prediction of outcomes of stone treatments. The synergy between urologists, nephrologists, and scientists in basic kidney stone research will enhance the depth and breadth of investigations, leading to a more comprehensive understanding of kidney stone formation.

The objective of this study was to explore the mechanical properties of AlCrSiN and AlTiSiN coatings deposited on Inconel and steel substrates after thermal treatments of 500 °C and 800 °C. Nanoindentation was used to measure the hardness and elastic modulus of the coatings, and microindentation was used for observing the contact damage with Hertzian contact loadings. Microscratch and Mercedes tests were used to evaluate the adhesive strength between coating and substrate with both progressive and static loads, respectively. The surface damage was inspected by optical microscopy and scanning electron microscopy (SEM). Focus ion beams (FIB) were used to mill the cross-sections in order to detect the extent and mode of failure. The results show that AlCrSiN coatings and Inconel substrates exhibit better mechanical performance, even after thermal treatments.

This work aimed at the antimicrobial functionalization of 3D-printed polymer-infiltrated biomimetic ceramic networks (PICN). The antimicrobial properties of the polymer-ceramic composites were achieved by coating them with human- and environmentally safe silver nanoparticles trapped in a phenolated lignin matrix (Ag@PL NPs). Lignin was enzymatically phenolated and used as a biobased reducing agent to obtain stable Ag@PL NPs, which were then formulated in a silane (γ-MPS) solution and deposited to the PICN surface. The presence of the NPs and their proper attachment to the surface were analyzed with spectroscopic methods (FTIR and Raman) and X-ray photoelectron spectroscopy (XPS). Homogeneous distribution of 13.4 ± 3.2 nm NPs was observed in the transmission electron microscopy (TEM) images. The functionalized samples were tested against Gram-positive ( Staphylococcus aureus ) and Gram-negative ( Pseudomonas aeruginosa ) bacteria, validating their antimicrobial efficiency in 24 h. The bacterial reduction of S. aureus was 90% in comparison with the pristine surface of PICN. To confirm that the Ag-functionalized PICN scaffold is a safe material to be used in the biomedical field, its biocompatibility was demonstrated with human fibroblast (BJ-5ta) and keratinocyte (HaCaT) cells, which was higher than 80% in both cell lines.

Urothelial tumour of the upper urinary tract is a rare neoplasm, but unfortunately, it has a high recurrence rate. The reduction of these tumour recurrences could be achieved by the intracavitary instillation of adjuvant chemotherapy after nephron-sparing treatment in selected patients, but current instillation methods are ineffective. Therefore, the aim of this in vitro study is to evaluate the cytotoxic capacity of a new instillation technology through a biodegradable ureteral stent/scaffold coated with a silk fibroin matrix for the controlled release of mitomycin C as an anti-cancer drug. Through a comparative study, we assessed, in urothelial carcinoma cells in a human cancer T24 cell culture for 3 and 6 h, the cytotoxic capacity of mitomycin C by viability assay using the CCK-8 test (Cell counting Kit-8). Cell viability studies in the urothelial carcinoma cell line confirm that mitomycin C embedded in the polymeric matrix does not alter its cytotoxic properties and causes a significant decrease in cell viability at 6 h versus in the control groups. These findings have a clear biomedical application and could be of great use to decrease the recurrence rate in patients with upper tract urothelial carcinomas by increasing the dwell time of anti-cancer drugs.

The aim of this work was to prepare and characterize polymer-ceramic composite material for dental applications, which must resist fracture and wear under extreme forces. It must also be compatible with the hostile environment of the oral cavity. The most common restorative and biocompatible copolymer, 2,2-bis(p-(2'-2-hydroxy-3'-methacryloxypropoxy)phenyl)propane and triethyleneglycol dimethacrylate, was combined with 3D-printed yttria-stabilized tetragonal zirconia scaffolds with a 50% infill. The proper scaffold deposition and morphology of samples with 50% zirconia infill were studied by means of X-ray computed microtomography and scanning electron microscopy. Samples that were infiltrated with copolymer were observed under compression stress, and the structure's failure was recorded using an Infrared Vic 2D TM camera, in comparison with empty scaffolds. The biocompatibility of the composite material was ascertained with an MG-63 cell viability assay. The microtomography proves the homogeneous distribution of pores throughout the whole sample, whereas the presence of the biocompatible copolymer among the ceramic filaments, referred to as a polymer-infiltrated ceramic network (PICN), results in a safety "damper", preventing crack propagation and securing the desired material flexibility, as observed by an infrared camera in real time. The study represents a challenge for future dental implant applications, demonstrating that it is possible to combine the fast robocasting of ceramic paste and covalent bonding of polymer adhesive for hybrid material stabilization.

Objective: To review dermatofibrosarcoma protuberans (DFSP), which is a soft tissue neoplasm of the skin that can rarely affect the genitals., Material and Method: We report a case of inguinal DFSP in a 40-year-old male who presented a slow-growing mass adjacent to the spermatic cord., Results: After extensive surgical resection pathological analysis confirmed the diagnosis of DFSP with resection margins affected, so reoperation with margin exeresis and inguinal orchiectomy was required., Conclusions: DFSP is rarely localized in the inguinoescrotal region and it requires wide excision and sometimes orchiectomy.

To demonstrate that percutaneous nephrolithotomy (PCNL) in the Galdakao-modified supine Valdivia position can be safely and effectively reproduced by different surgeons. A multicentre retrospective cross-sectional case study on 317 patients was conducted. The centres enrolled were four hospitals from the Spanish National Health System and provided data for consecutive PCNL from January 2008 to December 2010. The patients were divided into two groups: the Galdakao group (134; operated on by the master PCNL surgeon) and the other surgeons group (183; operated on by the other surgeons). The results of the technique were analysed relative to success and complications. Finally, a multivariate analysis introducing the covariates age, gender, BMI, ASA and type of stone was performed (backward stepwise logistic regression). The univariate analysis did not reveal differences in age, gender and ASA scores (p > 0.05) between the Galdakao group and the other surgeons group. The success rate was 80.6 % in the Galdakao group and 72.7 % in the other surgeons group (p = 0.01), and the complication rate was 16.4 and 26.2 %, respectively (p = 0.03). Complications were categorised based on the Clavien classification, and no differences were discovered between the groups (p = 0.19). The logistic regression confirmed only the surgeon and the stone type as independent predictive variables. PCNL in the Galdakao-modified supine Valdivia position is feasible for the use by different urologic surgeons. The results depend on the surgeon's experience, but with specific training and, maybe, selecting the simplest cases at the beginning, it is possible to achieve competitive results.

Objective: To analyse the complaints made by users of the National Health System in the University Hospital of Getafe (Madrid, Spain), to characterise trends in complaint rates over time and to appraise the quality control in the management of complaints., Material and Methods: All complaints made between January 2000 and December 2005 were recorded and the incidence rate and annual percent change were calculated. The relationships between complaints and time were analysed. Finally, the percentage of complaints correctly dealt with in less than 30 days was calculated., Results: The number of complaints increased from 132.93 to 482.28 per 100,000 inhabitants. The annual percent increase was +15.21. There was a relationship between several types of complaints and time (disagreement with health care, the organisation, with loss of documents, with clinical information, with delays in surgical and non-surgical treatment and cancellations. In 2004, only 24.8% of complaints were answered in time, but increased to 44% in 2005., Conclusions: There was an increase in the incidence of the complaints in the University Hospital of Getafe (Madrid) during the period studied. The users give greater importance to the technical and human aspects of health care compared to organisational and planning aspects. The quality control in the management of the complaints is poor.

Objective: To address detection rates and clinical features of the cancers detected with low prostate specific antigen (PSA) levels., Methods: In the context of a prostate cancer (PCa) screening program 1097 men attended to a new rescreen round. Sextant prostate biopsy was recommended when PSA > or =3 ng/ml. We also recommended to undergo biopsy in the range 1.0-2.99 ng/ml when free to total (f/t) PSA ratio < or =20%. Detection rate was calculated and clinical features of the cancers detected were studied., Results: Mean age was 61.1 years. A total of 497 (45.3%) had total PSA <1.0 ng/ml, 439 (40%) between 1.0 and 2.99 ng/ml, and 161 (14.7%) > or =3.0 ng/ml. In the group with PSA between 1.0 and 2.99 ng/ml and f/t PSA ratio < or =20% a total of 249 biopsies were indicated (159 performed, acceptance 63.9%), and 15 cancers detected (detection rate 9.4%). Biopsy was recommended to 72 men with PSA between 3.0 and 3.99 ng/ml, performed in 56 (77.8%), and 12 tumors detected (detection rate 21.4%). All cancers in the study were clinically localized. Only 4 out of 15 cancers with PSA in the range 1.0-2.99 ng/ml (26.7%) fulfilled clinical criteria of insignificant cancer. Two were poorly differentiated and found to have patologically extracapsular disease. None of the 12 patients with PCa and PSA between 3.0 and 3.99 ng/ml had poorly differentiated features and only one complied with criteria of insignificant cancer. One out of seven who underwent RRP was found to have extracapsular disease., Conclusions: Cancer detection in low PSA ranges is lower but still relevant. The detection of potentially aggresive cancers is still of concern.

Objectives: To document the extent of prostate-specific antigen (PSA)-testing in the general population at Getafe (Spain) outside our prostate cancer (PC) screening program, and to check its performance in terms of PC detection., Methods: A total of 5371 PSA-test records (1997-1999) were reviewed and testing rates estimated per 1000 person-years. The extent of patient referral (men referred to our facilities) was calculated adjusting for PSA levels. To approach the performance of testing in the general population, our PC screening program acted as a standard for comparison. The probability of missing one PC in the general population was estimated in terms of number of men necessary to screen (NNS). Calculations were made adjusting for PSA levels., Results: PSA-testing rate in the general population was 21.6/1000 person-years. In the age-group 55-69 years, this rate was 86.8/1000 (152.6 in men >70 years). Referral rates were 67.9 and 39.5% for men with PSA 4-10 and >10 ng/ml, respectively. Overall PC detection rate was 1.76%. Detection rates for PSA 4-10 and >10 ng/ml were 4.66 and 12.94%, respectively. When compared with the performance of the screening program, for every 17 men with a PSA in the range 4-10 ng/ml one cancer was missed (95% confidence interval (CI), 9-580). Similarly, one cancer was lost for every four men with a PSA >10 ng/ml (95% CI, 2-8)., Conclusions: The extent of opportunistic testing in our setting is very high, particularly in the older age groups. Opportunistic screening renders PC detection rates lower than expected for every PSA level and cannot be encouraged.