Microstructural, Biomechanical, and In Vitro Studies of Ti-Nb-Zr Alloys Fabricated by Powder Metallurgy

Data Availability Statement: The data underpinning this publication can be accessed from Brunel University London’s data repository, Brunelfigshare here under a CCBY licence: https://doi.org/10.17633/rd.brunel.5446813.v1. Non-digital data supporting this study are stored by the corresponding author at Brunel University. Details of how to request access to these data are provided here: https://doi.org/10.17633/rd.brunel.5446813.v1.Supplementary Materials: The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/ma16124240/s1, Figure S1: Plasmid–DNA interaction assay for Ti-Nb-Zr based alloys. The migration pattern of plasmid DNA incubated with Ti-Nb-Zr-based alloys and TiRG4 reference materials is shown in the figure. The bands are labeled as NC: Nicked circular and SC: Supercoiled; ddH2O served as a negative control.Copyright © 2023 by the authors. This study investigated the microstructures, mechanical performances, corrosion resistances, and in vitro studies of porous Ti-xNb-10Zr (x: 10 and 20; at. %) alloys. The alloys were fabricated by powder metallurgy with two categories of porosities, i.e., 21–25% and 50–56%, respectively. The space holder technique was employed to generate the high porosities. Microstructural analysis was performed by using various methods including scanning electron microscopy, energy dispersive spectroscopy, electron backscatter diffraction, and x-ray diffraction. Corrosion resistance was assessed via electrochemical polarisation tests, while mechanical behavior was determined by uniaxial compressive tests. In vitro studies, such as cell viability and proliferation, adhesion potential, and genotoxicity, were examined by performing an MTT assay, fibronectin adsorption, and plasmid-DNA interaction assay. Experimental results showed that the alloys had a dual-phase microstructure composed of finely dispersed acicular hcp α-Ti needles in the bcc β-Ti matrix. The ultimate compressive strength ranged from 1019 MPa to 767 MPa for alloys with 21–25% porosities and from 173 MPa to 78 MPa for alloys with 50–56% porosities. Noted that adding a space holder agent played a more critical role in the mechanical behaviors of the alloys compared to adding niobium. The pores were largely open and exhibited irregular shapes, with uniform size distribution, allowing for cell ingrowth. Histological analysis showed that the alloys studied met the biocompatibility criteria required for orthopaedic biomaterial use.EPSRC Future LiME Hub (EP/N007638/1); PhD studentship, the Republic of Turkey Ministry of National Education

Prognostic significance of pathologic lymph node invasion in metastatic renal cell carcinoma in the immunotherapy era

Background This study aimed to test the prognostic significance of pathologically confirmed lymph node invasion in metastatic renal cell carcinoma (mRCC) patients in this immunotherapy era. Methods Surgically treated mRCC patients were identified in the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2018. Kaplan-Meier plots and multivariable Cox-regression models were fitted to test for differences in cancer-specific mortality (CSM) and overall mortality (OM) according to N stage (pN0 vs pN1 vs. pNx). Subgroup analyses addressing pN1 patients tested for CSM and OM differences according to postoperative systemic therapy status. Results Overall, 3149 surgically treated mRCC patients were identified. Of these patients, 443 (14%) were labeled as pN1, 812 (26%) as pN0, and 1894 (60%) as pNx. In Kaplan-Meier analyses, the median CSM-free survival was 15 months for pN1 versus 40 months for pN0 versus 35 months for pNx (P < 0.001). In multivariable Cox regression analyses, pN1 independently predicted higher CSM (hazard ratio [HR], 1.88; P < 0.01) and OM (HR, 1.95; P < 0.01) relative to pN0. In sensitivity analyses addressing pN1 patients, postoperative systemic therapy use independently predicted lower CSM (HR, 0.73; P < 0.01) and OM (HR, 0.71; P < 0.01). Conclusion Pathologically confirmed lymph node invasion independently predicted higher CSM and OM for surgically treated mRCC patients. For pN1 mRCC patients, use of postoperative systemic therapy was associated with lower CSM and OM. Consequently, N stage should be considered for individual patient counseling and clinical decision-making

Regional differences in clear cell metastatic renal cell carcinoma patients across the USA

Purpose To test for regional differences in clear cell metastatic renal cell carcinoma (ccmRCC) patients across the USA. Methods The Surveillance, Epidemiology, and End Results (SEER) database (2000–2018) was used to tabulate patient (age at diagnosis, sex, race/ethnicity), tumor (N stage, sites of metastasis) and treatment characteristics (proportions of nephrectomy and systemic therapy), according to 12 SEER registries. Multinomial regression models, as well as multivariable Cox regression models, tested the overall mortality (OM) adjusting for those patient, tumor and treatment characteristics. Results In 9882 ccmRCC patients, registry-specific patient counts ranged from 4025 (41%) to 189 (2%). Differences across registries existed for sex (24–36% female), race/ethnicity (1–75% non-Caucasian), N stage (N1 25–35%, NX 3–13%), proportions of nephrectomy (44–63%) and systemic therapy (41–56%). Significant inter-registry differences remained after adjustment for proportions of nephrectomy (46–63%) and systemic therapy (35–56%). Unadjusted 5-year OM ranged from 73 to 85%. In multivariable analyses, three registries exhibited significantly higher OM (SEER registry 5: hazard ratio (HR) 1.20, p = 0.0001; SEER registry 7:HR 1.15, p = 0.008M SEER registry 10: HR 1.15, p = 0.04), relative to the largest reference registry (n = 4025). Conclusion Important regional differences including patient, tumor and treatment characteristics exist, when ccmRCC patients included in the SEER database are studied. Even after adjustment for these characteristics, important OM differences persisted, which may require more detailed analyses to further investigate these unexpected differences

Effects on growth of persimmon (Diospyros virginiana) rootstock of arbuscular mycorrhizal fungi species

Persimmon (Diospyros kaki Thunb.) is grown in many parts of the world that display subtropical climate conditions, including Turkey. There are 2 common rootstocks used in its production: D. kaki and D. virginiana Thunb. Arbuscular mycorrhiza (AM), a symbiosis between plant roots and members of an ancient phylum of fungi, Glomeromycota, improves root development, water supply, and nutrients such as phosphate and zinc in the host plant. In this study, the effects of 5 AM fungi species (Glomus mosseae, G. clarium, G. etunicatum, G. caledonium, and G. intraradices) on plant growth, chlorophyll concentration, and chlorophyll fluorescence (Fv’/Fm’) in D. virginiana were investigated under greenhouse conditions. We determined that mycorrhizal inoculations increased shoot and root dry weight compared to the noninoculated plants. Plants inoculated with G. etunicatum showed the highest total plant dry weight. Highest leaf chlorophyll concentration was measured in a plant inoculated with G. caledonium. The results of chlorophyll fluorescence were similar for all AM inoculations; however, they significantly differed from those of noninoculated plants. The results demonstrated the benefit potential of mycorrhizal inoculations for persimmon production. © TÜBİTAK

Molecular characterization of sour orange (citrus aurantium) accessions and their relatives using SSR and SRAP markers

Citrus production with its many varieties is of importance since it provides economically important products for Turkish exports. Sour orange is a rootstock commonly used for propagating the different scion varieties. Knowledge of the genetic diversity of the rootstock accessions would be useful in order to improve citrus breeding programs. We studied genetic relationships and diversity of 51 accessions of sour orange (Citrus aurantium) and their relatives using SSR (simple sequence repeat) and SRAP (sequence-related amplifed polymorphism) molecular markers. Twenty-one SRAP primer combinations were tested on these accessions and relatives, producing 167 polymorphic fragments, with a mean of 8.0 and a mean polymorphism information content value of 0.47. Seventeen SSR primers also produced 30 polymorphic fragments, with a mean of 1.4 per primer and a mean polymorphism information content value of 0.39. The unweighted pair-group method with arithmetic average analysis using combined SSR and SRAP data showed a similarity range from 0.71 to 1.00 among the accessions. In the cluster analysis, sour orange relatives were indicated as a separate group from sour orange. 'Macrophylla' and 'Mexican lime' were the accessions most distinct (0.71) from the others. We conclude that genetic diversity in these sour orange accessions is lower and some of them were identical. © FUNPEC-RP www.funpecrp.com.br

Impact of Age on Long-Term Urinary Continence after Robotic-Assisted Radical Prostatectomy

Aim and Objectives: We aimed to test the impact of age on long-term urinary continence (≥12 months) in patients undergoing robotic-assisted radical prostatectomy. Methods and Materials: We relied on an institutional tertiary-care database to identify the patients who underwent robotic-assisted radical prostatectomy between January 2014 and January 2021. Patients were divided into three age groups: age group one (≤60 years), age group two (61–69 years) and age group three (≥70 years). Multivariable logistic regression models tested the differences between the age groups in the analyses addressing long-term urinary continence after robotic-assisted radical prostatectomy. Results: Of the 201 prostate cancer patients treated with robotic-assisted radical prostatectomy, 49 (24%) were assigned to age group one (≤60 years), 93 (46%) to age group two (61–69 years) and 59 (29%) to age group three (≥70 years). The three age groups differed according to long-term urinary continence: 90% vs. 84% vs. 69% for, respectively, age group one vs. two vs. three (p = 0.018). In the multivariable logistic regression, age group one (Odds Ratio (OR) 4.73, 95% CI 1.44–18.65, p = 0.015) and 2 (OR 2.94; 95% CI 1.23–7.29; p = 0.017) were independent predictors for urinary continence, compared to age group three. Conclusion: Younger age, especially ≤60 years, was associated with better urinary continence after robotic-assisted radical prostatectomy. This observation is important at the point of patient education and should be discussed in informed consent