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The performance of CoCrMo alloy in orthopaedic implants may be unfavourably affected by hyaluronic acid (HA) in synovial fluid. In this study, the authors aimed to understand the interactions between HA and CoCrMo using dedicated electrochemical experiments and surface analyses. A sequence of electrochemical measurements (open‐circuit potential, linear polarization resistance, potentiodynamic and potentiostatic polarizations) was run on LC‐CoCrMo (ASTM F1537) in Dulbecco's phosphate‐buffered saline (DPBS) solution with and without HA and in DPBS mixed with newborn calf serum (NCS) and HA, partially under simultaneous recording of surface pH using custom‐made microelectrodes. Samples were analysed by optical and electron microscopy. HA had no significant impact on the corrosion potential of CoCrMo alloy (ECORR = −173 ± 8, −211 ± 16, and −254 ± 30 mVAg/AgCl, in DPBS, DPBS + HA, and DPBS + NCS + HA, respectively). Average current density values at the transpassive domain were double in DPBS compared to DPBS + HA and DPBS + NCS + HA. At potentials above +0.6 VAg/AgCl, surface pH values decreased from 7.5 to 6.5 in DPBS and from 7.5 to below 4 in DPBS + HA. In conclusion, the presence of HA did not compromise the corrosion resistance of CoCrMo alloy at free potential, but it enhanced acidic conditions at the near surface under anodic‐applied potential in the transpassive domain.

Background Intestinal ultrasound (IUS) is accurate to assess endoscopic activity in ulcerative colitis (UC). The Milan ultrasound criteria (MUC) is a validated scoring system to assess and grade endoscopic activity in UC. The most accurate cutoff value for MUC was > 6.2 for endoscopic activity (defined as a Mayo endoscopic score, MES ≥ 2). The aim of this study was to assess the predictive value of IUS and MUC for treatment response in a longitudinal cohort, using colonoscopy (CS) as reference standard. Methods Consecutive active UC patients starting biologic therapy were included. All patients underwent CS, IUS, clinical and faecal calprotectin (FC) evaluations prior commencing a biological therapy, and within one year (mean 9.4 months). In addition, patients were evaluated by IUS, clinical and FC assessments at week 12. The primary objective was to evaluate whether ultrasound improvement (defined as MUC ≤ 6.2) at week 12 predicted endoscopic improvement at reassessment (defined as MES ≤ 1). Endoscopic remission was defined as MES = 0. Results Forty-nine patients were included (59% under infliximab, 29% under vedolizumab, 8% under adalimumab, 4% under ustekinumab). MUC and MES correlated at reassessment (r= 0.767, p < 0.001). Ultrasound improvement at week 12 was the only independent predictor for MES ≤ 1 and MES = 0 at reassessment (OR 5.80, p = 0.010; OR 10.41, p = 0.041; respectively). Ultrasound improvement at week 12 showed NPV of 96% for detecting MES = 0. A ≥ 2 reduction of the MUC score predicted MES=0 (area under the curve, AUC 0.816). MUC ≤ 4.3 was the most accurate cut-off value for MES = 0 (AUC 0.876). The responsiveness ratio of Guyatt for the MUC was 1.73 and the standardized effect size ratio was 1.6. Both these values > 0.8 indicate a large effect of responsiveness for the MUC. Conclusion MUC is highly accurate to monitor treatment response. Ultrasound improvement after the induction period may predict long-term endoscopic response. The MUC may be used both in clinical trials and routine practice.

The management of pituitary adenomas in the elderly has become a relevant clinical issue, in relationship with improved life expectancy and spreading use of imaging techniques. In this single-center and retrospective study, we investigated the impact of age on peri- and postsurgical outcomes in patients undergoing transnasal sphenoidal (TNS) surgery for pituitary adenomas. One-hundred-sixty-nine patients (62% males) undergoing endoscopic transphenoidal (TNS) surgery for nonfunctioning pituitary adenomas (NFPAs) were enrolled. Patients were subdivided into three groups according to age tertiles: ≤56 (group 1), 57–69 (group 2), and ≥70 (group 3) years. Postsurgical and endocrinological outcomes were evaluated and compared among the three age groups. 37/169 patients (21.9%) developed at least one perisurgical complication, without significant association with the patients’ age (P = 0.838), Charlson co-morbidity score (P = 0.326), and American Society of Anesthesiologist score (P = 0.616). In the multivariate regression analysis, the adenoma size resulted the only determinant of perisurgical complication (odds ratio [OR] 1.07, 95% confidence interval [C.I.] 1.00–1.13; P = 0.044). The development and the recovery of at least one pituitary hormone deficiency were observed in 12.2% and 14.2% of patients, respectively. The risk of developing new pituitary hormone deficiencies was correlated with cavernous sinus invasion as evaluated by magnetic resonance imaging (hazard ratio [HR] 4.19, 95% C.I. 1.39–12.66; P = 0.010), whereas the probability to normalize at least one pituitary hormone deficiency was significantly correlated with younger age of patients (HR 0.27, 95% CI 0.12–0.61; P = 0.002). The results of this study reinforce the concept that endoscopic TNS surgery is a safe therapeutic option in the elderly patients with NFPA, even in presence of comorbidities and high anesthetic risk.

We report on the observation of non-metallic electrical conduction, resistive switching, and a negative temperature coefficient of resistance in cluster-assembled nanostructured gold films above the electrical percolation and in strong-coupling regime, from room to cryogenic temperatures (24K). The structure of the films is characterized by an extremely high density of randomly oriented crystalline nanodomains, separated by grain boundaries. The observed behavior can be explained by considering space charge limited conduction and Coulomb blockade phenomena highlighting the influence of the high density of defects and grain boundaries on the localization of conduction electrons. Our findings have implications for a broad class of resistive switching systems based on random assemblies of nanoobjects., Comment: 12 pages, 4 figures

Background Intestinal ultrasound (IUS) is accurate and non-invasive to detect and monitor disease activity in Crohn’s disease (CD). The Bowel Ultrasound Score (BUSS= 0.75 × bowel wall thickness + 1.65 × presence (1) or absence (0) of bowel wall flow) demonstrated high accuracy in detecting therapy-related changes, and good correlation with the Simple Endoscopic Score for CD (SES-CD). The most accurate cutoff value for BUSS was 3.52 for endoscopic remission (SES-CD ≤ 2).This study aimed to prospectively evaluate ultrasound remission as a relevant treatment target. Methods Consecutive patients with active CD (SES-CD > 2) starting biologic treatments were included. Patients underwent colonoscopy and IUS at baseline and after 1 year of treatment. Clinical, biochemical and ultrasound assessments were additionaly performed at week 12. Primary outcome was to evaluate whether ultrasound remission at week 12 could predict endoscopic remission at week 54. Endoscopic remission was defined as SES-CD ≤ 2, ultrasound remission was defined by BUSS ≤ 3.52, clinical remission was defined by HBI (Harvey-Bradshaw Index) < 5, and biochemical remission was defined by normalization of C-reactive protein (< 5 mg/L) and fecal calprotectin (three different thresholds were assessed: < 250 µg/g, < 100 µg/g, < 50 µg/g). Results Ninety-three patients were included (8 under infliximab, 40 under adalimumab, 5 under vedolizumab and 40 under ustekinumab). Eighteen patients (19%) and 36 patients (39%) achieved endoscopic remission and ultrasound remission at week 54, respectively. CD patients with ultrasound remission at week 12 were more likely to achieve endoscopic remission (odds ratio [OR] 6.88 [2.14–22.04]; p = 0.001) and ultrasound remission (OR 4.26 [1.61–11.24]; p = 0.003) at week 54. Calprotectin value < 50 µg/g at week 12 predicted endoscopic remission at univariable (OR 3.14 [1.04–9.45]; p = 0.041), but not at multivariable analysis. No other clinical or biochemical variables at week 12 predicted endoscopic and/or ultrasound remission at week 54. Conclusion Ultrasound remission achieved at week 12 may predict long-term endoscopic remission and may be a strategic treatment target, both in clinical practice and in clinical trials.

CoCrMo alloys are well-established biomaterials used for orthopedic joint replacement implants. However, such alloys have been associated with clinical problems related to wear and corrosion. A new generation of austenitic high-nitrogen steels (AHNSs) has been developed for biomedical applications. Here, we have addressed influences of hyaluronic acid, combined with inflammatory (oxidizing) conditions, on tribocorrosion of the high-nitrogen FeCrMnMoN0.9 steel (DIN/EN X13CrMnMoN18-14-3, 1.4452), and of the low carbon CoCrMo0.03 alloy (ISO 5832-12). We aimed to elucidate critical and clinically relevant conditions affecting the implant's performance in certain orthopedic applications. Tribocorrosion tests were conducted in triplicate, with discs under reciprocating sliding wear against a ceramic ball. Different lubricants were prepared from standardized bovine serum solution (ISO 14242-1), with variable additions of hyaluronic acid (HA) and hydrogen peroxide (H2 O2 ). Test conditions were: 37°C, 86,400 cycles, 37 N load (20-40 MPa after run-in phase). Volumetric wear was quantified; surfaces were evaluated by electrochemical parameters and microscopy/spectroscopy analyses (SEM/EDS). Factorial analysis of variance tests was conducted to examine the effects of HA, H2 O2 , and test material on wear- and corrosion-related dependent variables. Tribocorrosion performances of CoCrMo0.03 and FeCrMnMoN0.9 were comparable in fluids without H2 O2 . With higher H2 O2 concentrations, tribocorrosion increased for CoCrMo0.03 , while this was not the case for FeCrMnMoN0.9 . HA significantly enhanced wear of CoCrMo0.03 in the absence of H2 O2 , while it mitigated the tribocorrosive action of 3 mM H2 O2 ; HA had no impact on FeCrMnMoN0.9 . These results indicate a favorable performance of FeCrMnMoN0.9 compared to CoCrMo0.03 , and encourage further research on AHNS for certain orthopedic applications.

Background Lémann Index (LI) is a well-established validated index to assess cumulative bowel damage in Crohn’s disease (CD). Magnetic resonance imaging and colonoscopy are usually used to measure LI. We assessed the accuracy of bowel ultrasound in assessing LI and its sensitivity to change in a longitudinal cohort of CD patients, in comparison with magnetic resonance imaging. Methods We performed a prospective observational study of 60 patients with active CD. All patients underwent bowel ultrasound, magnetic resonance imaging, and colonoscopy at baseline and at reassessment, within 1 year from treatment with biologics (30 patients were treated with adalimumab, 22 with ustekinumab, four patients with infliximab, and four with vedolizumab). The primary analysis was to determine the correlation between magnetic resonance-based LI and ultrasonography-based LI, both at baseline and at reassessment. Additional analyses established the magnitude of change in LI over time, measured by magnetic resonance imaging and colonoscopy, and its correlation with those in LI measured by bowel ultrasound and colonoscopy. Results The mean values of magnetic resonance-based LI and ultrasonography-based LI at baseline were 6.3 (± 4.8) and 6.4 (± 4.9) respectively, p= 0.39; at reassessment, 5.3 (± 4.6) and 5.5 (± 4.9) respectively, p= 0.30. No differences were observed according to different treatments (Table1). There were significant differences between LI assessed at baseline and LI at reassessment, independently by the imaging tool used for measuring it (p < 0.05). Very high correlations were observed between the magnetic resonance-based LI and ultrasonography-based LI (at baseline, r= 0.964, p < 0.0001; at reassessment, r= 0.970, p < 0.0001) (Figure 1). The magnitude of change in magnetic resonance-based LI correlated with those in ultrasonography-based LI (r= 0.871; p < 0.0001) (Figure 1). Conclusion LI can be measured by bowel ultrasound alternatively to magnetic resonance imaging, without no meaningful change in its value.

Background We assessed the accuracy and the responsiveness to change of Milan Ultrasound Criteria (MUC) in patients with ulcerative colitis (UC), using colonoscopy as the reference standard. Methods We performed a prospective observational study of 49 patients with active UC. All patients underwent bowel ultrasound and colonoscopy at baseline and at reassessment, at week 48, after treatment with biologics (29 patients were treated with infliximab, 14 with vedolizumab, four with adalimumab, two with ustekinumab). Furthermore, patients underwent bowel US also at week 12 and 24. Disease activity was quantified using Mayo endoscopic subscore and MUC. The primary analysis was to determine the accuracy of MUC in identification of endoscopic remission defined as a Mayo endoscopic subscore < 2. Additional analyses established the accuracy of MUC in determining change in lesion severity. Logistic regression was used to examine the relationship between the absence or presence (0/1) of endoscopic remission at reassessment as the dependent variable and possible predictors at week 12 as the independent variables. The model was performed using the stepwise backward method. Results Eighteen patients (37%) got endoscopic remission at reassessment. In Table 1 are summarized endoscopic and ultrasound outcomes achieved at reassessment according to the different treatments. MUC < 6.2 determined endoscopic remission with 83% sensitivity, 84% specificity, 84% accuracy, 75% PVP and 90% PVN (Table 2). MUC was sensitive to change in ulcerative colitis [Guyatt’s responsiveness index: 1.73; standardised effect size ratio: 2.0]. MUC changed significantly from baseline to reassessment [8.72 (7.78−9.14) vs 7.60 (4.71−8.53), p < 0.0001], with the largest drop at week 12 [8.72 (7.82−9.19) vs 7.46 (5.80−7.98), p < 0.0001] (Figure 1). A change of -2 in MUC overtime predicted endoscopic remission at reassessment (AUC 0.806, 95% CI 0.667–0.904; sensitivity 89%, specificity 77%). At multivariable analysis only MUC < 6.2 at week 12 was statistically significantly associated with endoscopic remission at reassessment (Table 3). Conclusion MUC accurately detects endoscopic remission. MUC is a highly responsive, reliable tool for assessing treatment response in patients with ulcerative colitis.

Periprosthetic fluids often contain reactive oxygen species, including H(2)O(2), that are generated during inflammatory processes. Here, we investigated the fretting-corrosion behavior of CoCrX-alloys (X = Mo, Fe) in a complex protein-containing lubricant, with and without the addition of H(2)O(2). Given the known protective role of molybdenum as an alloying element in metal degradation, we considered its effects by designing a two-way factorial experiment. The aim of the study was to investigate tribocorrosive mechanisms in modular joints of knee and hip prostheses. A previously described test-rig was used to run fretting corrosion tests of CoCrX-alloys with (X=Mo) and without (X=Fe) molybdenum against TiAl6V4 in bovine calf serum (BCS) with and without a physiological relevant H(2)O(2) level (3 mM) in gross slip mode (4 Hz, ±50 μm, p(max)=0.18 GPa, 37 °C, 50,000 cycles). Two CoCr-pins were pressed against a cylindrical TiAl6V4-rod, forming a line contact. Normal and frictional forces, the displacement, and the open circuit potential (OCP) were measured and recorded continuously. The dissipated frictional work was independent of alloy composition. The addition of H(2)O(2) lowered the dissipated frictional work and increased wear, and this was significant in the absence of Mo. The mean OCP value was lower with Mo-containing than with Mo-free alloy in both pure BCS (p = .042), and BCS ± H(2)O(2) (p < .0005). The wear scar was deeper for the Mo-free alloy, and this was significant (p = .013) in the presence of H(2)O(2). These findings suggest a marked weakening of the passive film in the presence of H(2)O(2), which is mitigated by the availability of Mo.

The management of pituitary adenomas in the elderly has become a relevant clinical issue, in relationship with improved life expectancy and spreading use of imaging techniques. In this single-center and retrospective study, we investigated the impact of age on peri- and postsurgical outcomes in patients undergoing transnasal sphenoidal (TNS) surgery for pituitary adenomas.One-hundred-sixty-nine patients (62% males) undergoing endoscopic transphenoidal (TNS) surgery for nonfunctioning pituitary adenomas (NFPAs) were enrolled. Patients were subdivided into three groups according to age tertiles: ≤56 (group 1), 57-69 (group 2), and ≥70 (group 3) years. Postsurgical and endocrinological outcomes were evaluated and compared among the three age groups.37/169 patients (21.9%) developed at least one perisurgical complication, without significant association with the patients' age (P = 0.838), Charlson co-morbidity score (P = 0.326), and American Society of Anesthesiologist score (P = 0.616). In the multivariate regression analysis, the adenoma size resulted the only determinant of perisurgical complication (odds ratio [OR] 1.07, 95% confidence interval [C.I.] 1.00-1.13; P = 0.044). The development and the recovery of at least one pituitary hormone deficiency were observed in 12.2% and 14.2% of patients, respectively. The risk of developing new pituitary hormone deficiencies was correlated with cavernous sinus invasion as evaluated by magnetic resonance imaging (hazard ratio [HR] 4.19, 95% C.I. 1.39-12.66; P = 0.010), whereas the probability to normalize at least one pituitary hormone deficiency was significantly correlated with younger age of patients (HR 0.27, 95% CI 0.12-0.61; P = 0.002).The results of this study reinforce the concept that endoscopic TNS surgery is a safe therapeutic option in the elderly patients with NFPA, even in presence of comorbidities and high anesthetic risk.

Nickel-free, high-nitrogen austenitic steels (AHNS) have been introduced for biomedical applications, with encouraging results in terms of mechanical and corrosion properties. Here, we tested the corrosion resistance of a nickel-free high nitrogen steel (FeCrMnMoN0.9) in bovine serum solutions containing 0 or 3 g/L hyaluronic acid (HA), and 0, 3, or 30 mM hydrogen peroxide (H2 O2 ) simulating no, moderate, or strong inflammatory conditions, respectively. Nondestructive electrochemical measurements (open circuit potential [OCP], linear polarization resistance "RP ", and electrochemical impedance spectroscopy) were run in triplicate over 10 hr. The presence of HA had no significant effect either on the stabilized OCP values, or on the corrosion resistance of FeCrMnMoN0.9. Increasing H2 O2 concentrations shifted the OCP to more electropositive values; the corrosion resistance decreased only at a 30 mM H2 O2 . Final RP values at 0, 3, and 30 mM H2 O2 resulted in 1598 ± 276, 1746 ± 308, and 439 ± 47 kΩ cm2 , respectively. These values were 4-14 times higher, than the RP values measured on LC-CoCrMo in our previous study, conducted under identical conditions. While these findings are encouraging, future studies need to focus on tribocorrosive properties of the AHNS to evaluate its applicability in joint replacement.

Background Telemedicine is one of the major changes that clinicians have encountered over the past decade; in particular during the COVID-19 pandemic, televisits were rapidly implemented to guarantee patients’ assistance, with the intention of Health Care Providers (HCPs) to continue to use them beyond the pandemic. The aim of our national survey was to evaluate the current usage of telemedicine for IBD patients from their perspective, investigating patients’ impressions about telemedicine and factors affecting them through a Machine Learning (ML) analysis. Methods In March 2021, the Italian IBD patients’ association (AMICI Onlus) distributed to their members - through its mailing list and on social media platforms - an anonymous online questionnaire investigating the use of telemedicine. Socio-demographic and IBD characteristics were collected; the usage, patients’ satisfaction and trust of telemedicine were assessed through Likert scales. ML tools - Decision Trees (DT) and Random Forest (RF) - were applied to identify the determinants of patient’s perceptions about telemedicine; the produced RF ranking displays two indicators: %IncMSE and IncNodePurity. Results Nine hundred and seventy-eight IBD patients (women 58.9%) from every Italian region completed the questionnaire. Among the respondents, 87 (8.9%) personally had a telemedicine experience; 153 reported that their Centre performed a telemedicine service during the COVID-19 pandemic (24.2% televisits, 39.2% e-mails, 24.8% phone-calls, 3.9 % dedicated website, 7.9% others). Overall, 707 (72.3%) would trust a telemedicine service, 760 (77.7%) would like to have it also with another HCP (e.g., nutritionist, psychologist) and 778/961 (81%) would like to use telemedicine in the future (17 did not answer to this specific question); 792 (81%) stated they thought useful to have the possibility to use telemedicine and 847 (86.6%) would like their Centre to offer them this facility. Considering this last question as the output at the DT, the variable which have been found to influence the most this patients’ willingness is patient’s perception of the usefulness of telemedicine in treating their disease, since it represented the root of the tree explaining the results. The RF rankings confirmed that this variable influenced the most patients’ perception with the highest levels of %IncMSE and IncNodePurity(Figure 1). Conclusion The practice of telemedicine in the management of IBD patients has not been very relevant throughout Italy so far (less than 10%), but more than four every five respondents would like to use telemedicine. Machine learning analysis shows that the perceived usefulness of telemedicine service is the key point for patients who would like it was a part of usual clinical practice.

The problem of wear and corrosion of CoCrMo-implant surfaces in the human body following total joint replacement has been commonly investigated with tribocorrosion tests, using different lubricants meant to simulate the pseudo-synovial fluid. While results considering the synovial fluid components separately have highlighted their individual influence on the tribological performance of CoCrMo-alloy, an understanding about the influence of the synovial fluid components under the electrochemical point of view is missing. This work aims to investigate the effect of bovine serum albumin (BSA) and hyaluronic acid (HA) on electrochemical potential variations of CoCrMo alloys tested in a model synovial fluid. To simulate the environment inside the synovial capsule, the tests were performed inside a CO(2) incubator at 37°C. Open circuit potential, electrochemical impedance spectroscopy, cathodic and anodic potentiodynamic measurements were performed with different electrolytes, prepared with cell culture medium (RMPI-1640), BSA and HA. The final CoCrMo-surface was analyzed by SEM/EDS and infrared spectroscopy. The influence of HA on the corrosion of the CoCrMo-alloy depended on the presence of BSA proteins adsorbed on the CoCrMo-surface: EIS and anodic polarization results showed a corrosive action of HA in the absence of adsorbed proteins. In the presence of both BSA and HA, organometallic precipitates were found on the CoCrMo surface following reverse anodic polarization, which remind of corrosion products found in-vivo. These results indicate that HA affects the interaction of CoCrMo implant alloys with protein-containing model synovial fluids, and suggest that HA needs to be considered in tribocorrosion studies for more clinically relevant outcomes.

During joint inflammation, various reactive oxygen species (ROS) are present in the surrounding tissue and joint fluid. In the laboratory, hydrogen peroxide (H(2)O(2)) is typically used to simulate inflammatory conditions, and media containing proteins and hyaluronic acid (HA) are employed to simulate joint synovial fluid. Electrochemical interactions between H(2)O(2) and HA in the presence of a CoCrMo surface are expected, since HA molecules contain redox-active moieties. We hypothesized that any redox reactions of these moieties with ROS will mitigate the oxidizing effect of H(2)O(2) on the CoCrMo surface, limiting the corrosion rate of the metal. Non-destructive electrochemical measurements (open circuit potential, linear polarization resistance and electrochemical impedance spectroscopy) were used to investigate the corrosion response of CoCrMo in synovial model fluid containing physiologically relevant concentrations of albumin proteins and hyaluronic acid, with and without H(2)O(2). Two different molarities of H(2)O(2), 3 mM and 30 mM, were tested. While both molarities are within physiological limits, 3mM is well within the range HA could mitigate, whereas 30 mM is not. Contrary to our hypothesis, HA did not alleviate corrosion in 3 mM H(2)O(2) and even caused a corrosion increase in the case of 30 mM H(2)O(2). The decrease in corrosion resistance of the alloy may be attributed to the complexation of degenerated HA molecular chains with chromium ions released from the metallic surface, which are necessary to build a protective oxide film. This finding has clinical implications, suggesting that HA accelerates corrosion of CoCrMo implants in the presence of strong inflammation.

Wear and corrosion in total hip replacement negatively impact implant service-life and patient well-being. The aim of this study was to generate a statistical response surface of material loss using an apparatus, capable of testing the effect of wear and corrosion products in situ on cells, such as macrophages. The test chamber of a ball-on-flat tribometer operating inside a CO2 incubator was integrated with an electrochemical setup and adapted for cell culture work. A 20-test series, following a 2-level 3-factor design of experiments, was performed with a ceramic head in reciprocating rotational motion against a CoCrMo-alloy disc, under constant load. The lubricant was cell culture medium (RPMI-1640 + 10 vol% bovine serum). Response surfaces were generated, which statistically showed the influence of motion amplitude, load, and potential on the total mass loss and wear scar volume of the metallic discs. Potential had the highest impact on the total mass loss, while motion amplitude and load significantly influenced the wear scar volume. The concentrations of the alloy elements found in the lubricants reflected the bulk-alloy stoichiometry. The total concentration of Co released into the lubricant (2.3–63 ppm by total mass loss, 1.5 to 62 ppm by ICP-MS) corresponded well with the known range to trigger cell response. Tribocorrosion tests in the presence of cells and tissues, such as macrophages, lymphocytes and/or synovium, will be carried out in the future.

Tribocorrosion of implants has been widely addressed in the orthopedic and dental research fields. This study is a systematic scoping review about research methods that combine tribocorrosion tests with cells/tissues cultures, aimed to identify related current problems and future challenges. We used 4 different databases to identify 1022 records responding to an articulated keywords search-strategy. After removing the duplicates and the articles that didn't meet the search-criteria, we assessed 20 full-text articles for eligibility. Of the 20 eligible articles, we charted 8 records on cell cultures combined with tribocorrosion tests on implant materials (titanium, CoCrMo, and/or stainless steel). The year of publication ranged from 1991 to 2019. The cell line used was mostly murine. Two records used fretting tests, while 6 used reciprocating sliding with pin-on-disc tribometers. An electrochemical three-electrode setup was used in 4 records. We identified overall two experimental approaches: cells cultured on the metal (5 records), and cells cultured near the metal (3 records). Research activities on tribocorrosion processes in the presence of cells have been undertaken worldwide by a few groups. After a limited initial interest on this topic in the 1990's, research activities have restarted in the last decade, renewing the topic with technologically more advanced setups and analytical tools. We identified the main problems to be the lack of test reproducibility and wear particle characterization. We believe that the main challenges lay in the interdisciplinary approach, the inter-laboratory validation of experiments, and the interpretation of results, particularly in relation to potential clinical significance.

In the northeast region of the Buenos Aires province, stone fruits, mainly peach, are cultivated. The harvest period is extended from October to January but some lapses are not covered because there are few varieties available or the varieties are not accepted by the market. For this reason, a breeding program has begun. 'Flavorcrest' and 'Dixiland' are varieties well adapted to the zone and cultivated at present, so they have been selected as parents for the new hybrids production. The present study shows the results obtained these last two years from the sequence of the pollinations and fertilization until the fruit collected and the final embryo growth was registered. Pollen viability, pollination efficiency, fruit set and fruit and seed measure were evaluated in a comparative way between those obtained from the self-fertilization and those obtained by cross-pollination. All these events were studied in relation to the climatic conditions registered in the respective period. 'Flavorcrest' did not display auto-incompatibility or self-fertility problems. Nevertheless, 90 days after pollination, the weight, length and thickness of the fruits collected from the cross-pollination treatment with 'Dixiland' were significantly greater than those obtained from autogamy.

Titanium is an interesting material for biomedical implants thanks to its physical and chemical properties. In particular, TiO2 coatings with a surface characterized by micro-patterning combined with nano-topography are extremely attractive for orthopaedic implants in terms of enhanced osteointegration and consequently improved implant fixation. In the present work, a new method for the preparation of TiO2 multi-scale structured coatings is presented. This method is based on three steps. Firstly, monodispersed polystyrene (PS) microsized beads are functionalized with TiO2 submicron particles by a wet process involving a cationic polyelectrolyte. Secondly, the resulting TiO2-PS composite particles in suspension are used to prepare coatings by electrophoretic deposition (EPD), a simple and flexible electrochemical technique. The EPD is performed cathodically, avoiding uncontrolled oxidation of the substrate. Finally, after removal of the PS spacers during the sintering process, TiO2 coatings with a combined micro- and nano-topography are achieved from deposits thicker than 100 mu m. This achievement presents two relevant aspects: potential applications of the multi-scale structured TiO2 surfaces (particularly in the biomedical field); the simplicity and flexibility of the process used. (C) 2009 Elsevier B.V. All rights reserved.

This study was triggered by our experience on electrophoretic deposition (EPD) with different suspension systems showing evidence of a particle concentration threshold, below which no deposit was formed. In this study, the role of particle concentration in the mechanism of EPD was investigated with a model system, consisting of isopropanol suspensions with TiO2 nanosized particles (d50 = 130 nm). The investigated concentration range was 0.01 - 0.4 vol% TiO2. Constant voltage EPD tests with variable particle concentration were performed for 1 min under different applied voltages (25 - 300 V corresponding to 62.5 - 750 V/cm). A longer deposition time (30 min) was tested for a lower concentration value (0.003 vol% TiO2). The deposition process was evaluated in situ by means of the current measured during EPD. The deposits obtained were characterized by weight and profile measurements and scanning electron microscope (SEM). The results confirmed the finding of a lower limit value of particle concentration, determining a threshold in the formation of an EPD coating. Above this threshold, proportionality between deposited mass and particle concentration was observed, in agreement with the equation of Hamaker. Below this threshold, the proportionality was lost with evidence of a lack of coating formation. A possible interpretation for this experimental finding was provided.

Composite bilayer coatings on Ti6Al4V substrates were prepared by electrophoretic deposition, a simple and fast low temperature coating technique. Biocompatible yttrium-stabilized zirconia (YSZ) in the form of nanoparticles and bioactive Bioglass® (45S5) in the form of microparticles were chosen as coating materials. The first layer consisted of 5 μm of YSZ, deposited with the intention to avoid any metal tissue contact. The second layer consisted of 15-μm thick 45S5-YSZ composite, supposed to react with the surrounding bone tissue and to enhance implant fixation. The adsorption of YSZ nanoparticles on 45S5 microparticles in organic suspension was found to invert the surface charge of the 45S5 particles from negative to positive. This enabled cathodic electrophoretic deposition of 45S5, avoiding uncontrolled anodization (oxidation) of the substrate. The coatings were sintered at 900°C for 2 h under argon flow. The characterization was performed using SEM, EDX, and nanoindentation (cross section). Potential applications in the orthopedics field are discussed. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007

The effect of alumina nanoparticles suspended in an aqueous acetate buffer solution on the tribocorrosion behaviour of a 316L steel/alumina sliding contact was investigated using a reciprocating wear test rig equipped with an electrochemical cell. Through the addition of 10% volume of alumina nanoparticles to an acetate buffer solution it was possible to reduce the coefficient of friction by a factor of 2 and the stainless steel wear by a factor of 10 and this over a range of electrochemical and mechanical conditions. The presence of alumina particles caused a significant wear on the alumina counter part. The lubricating behaviour of the suspension was comparable to a commercial oil in water emulsion used for metal cutting. The lubricating effect was attributed to a third body formed by nanoparticles trapped within the contact. The agglomeration state of the alumina particles and their size were found to play a critical role.

Flowers of Prunus persica (L.) Batch. cv. Forastero have an orange toral nectary. The nectariferous tissue was formed by densely packed parenchyma cells (secretory cells) and an epidermis with hairs and modified stomata. The epidermal cells were highly vacuolated with a striated cuticle. The ultrastructure of these cells contained a cytoplasm with endoplasmic reticulum, plastids, mitochondria and dictyosomes. Sub-epidermal cells were barely vacuolated and their ultrastructure was similar to that of the epidermal cells. Differences were observed only in the endoplasmic reticulum, which is organized in a parallel configuration. Plasmodesmata were found between adjacent secretory cells and between secretory and epidermal cells. An electron dense secretion occurred in the intercellular spaces and between the external tangential wall and the cuticle of the epidermal cells. According to the ultrastructural observations, the sugar solution could be passed through the symplast or the apoplast. The nectar could be exuded from the stomata and the micro-channels of the cuticle covering the epidermal cells.

In this work a new class of ionomeric block perfluropolyether (PFPE) polyurethanes are presented; these polymers are obtained in the form of aqueous dispersions due to the presence of hydrophilic sites (ionomeric groups such as acetates or trialkylammonium salts) along the macromolecular chain, offering the chance to combine PFPEs in a variety of possible structures for coating or surface treatments with an environmentally friendly use. X-ray photoelectron spectroscopy analysis at two different sampling depths, as well as time-of-flight secondary ion mass spectrometry analysis modelled by the use of principal component analysis (PCA), were used to investigate the first nanometres of the surface samples. It resulted in a clear surface enrichment in fluorine, and the different extent of the fluorine stratification will be discussed in relation to the ionic character, film-forming from water and cross-linking. Copyright © 2003 John Wiley & Sons, Ltd.

In a porcine model of endotoxic shock, we evaluated the circulatory and respiratory effects of NO synthase (NOS) blockade. Twenty anaesthetised pigs were divided into three groups and studied for 240 min after induction of endotoxic shock with lipopolysaccharides of Escherichia coli (LPS). After 180 min of endotoxic shock, one group ( n = 6) received aminoguanidine, another group ( n = 6) received N G -nitro-L -arginine methyl ester (L -NAME) and a third group ( n = 8) received only LPS. A sham group ( n = 3) was also studied. LPS decreased systemic arterial pressure and cardiac output (CO) and increased mean pulmonary arterial pressure (MPAP), pulmonary vascular resistance (PVR) and heart rate. Significant changes were also observed in compliance (−18.4%) and resistance (+33.6%) of the respiratory system. Aminoguanidine did not modify LPS-dependent effects, while, after L -NAME, a significant increase in MPAP, PVR and SVR and a decrease in CO were observed. In conclusion, aminoguanidine does not play a significant cardiocirculatory and pulmonary role in the short-term dysfunction of endotoxic shock, while L -NAME has a detrimental effect on haemodynamics, suggesting a protective role of constitutive NO production at vascular level during the early stages of endotoxaemia.

A surface study of two different monocomponent polyurethane coatings containing perfluoropolyether macromers is presented. Different techniques were used in order to investigate the structural characteristics of the two polymers. In particular, transmission infrared spectroscopy provided information about the chemical groups and linkages present in the polymer network, and attenuated total reflectance spectra showed a higher concentration of urea groups close to the surface. X-ray photoelectron spectroscopy analysis at two different sampling depths showed clear evidence of fluorine enrichment and nitrogen depletion in the first nanometres of material with respect to the bulk composition of the two polymers. Analysis of the outermost layer by time-of-flight secondary ion mass spectrometry confirmed the XPS data with a predominant presence of fluorinated fragments. Contact angles of the two coatings with water and paraffins were measured and the critical surface tension of wetting, γc, was estimated (13–16 mN m−1 at 20 °C) and compared with the known data of other fluoropolymers. Copyright © 2000 John Wiley & Sons, Ltd.

Autoselection systems allow the selection of a genetically engineered population independently of the growth medium composition. The structure of a Saccharomyces cerevisiae population transformed with an autoselection plasmid, in which a carbon-source-dependent modulation of the plasmid copy number occurs, was analysed. By means of flow cytometric procedures we tested the cell viability, dynamics of growth and heterologous protein production at single cell level. Such analyses allow the identification and the tracking of a specific cellular sub-population with a higher plasmid copy number which arises after the carbon source shift. The effects of the cellular plasmid distribution on the dynamics of growth are also discussed

Structural alterations of the myocardium, such as fibrosis and fatty infiltration, were observed in post-mortem examinations in patients with myotonic dystrophy, a familial multisystem neuromuscular disease with frequent cardiac involvement. To identify structural and anatomical abnormalities of the heart, 14 patients, aged 45 +/- 14 years, belonging to seven families, suffering from myotonic dystrophy were studied. Twelve-lead ECG, high resolution signal-averaged ECG, 24 h Holter monitoring, bidimensional echocardiography and cardiac magnetic resonance (MRI) were performed in all patients. Atrioventricular and/or intraventricular conduction disturbances were present in 11 patients; no major arrhythmias were recorded by Holter monitoring. Ventricular late potentials were present in four patients, absent in eight and not assessed in two (due to left bundle branch block). Echocardiogram showed abnormal findings (left ventricular hypertrophy, mitral valve prolapse, wall motion abnormalities) in eight patients. MRI revealed various cardiac alterations in 11 cases, specifically: left ventricular hypertrophy in seven, right ventricular hypertrophy in two, right ventricular enlargement in six, area of fatty infiltration and fibrosis in the right ventricle in six and in both ventricles in three. Although no clear correlations between the extent of fibro-lipomatous infiltrations and severity of cardiac dysfunction were found, fatty infiltrations were always observed in the most severely diseased patients and were frequently associated with the presence of more advanced conduction disturbances.(ABSTRACT TRUNCATED AT 250 WORDS)

In this work, a high molecular weight copolymer of tetrafluoroethylene and perfluoro-4-trifluoromethoxy-1,3-dioxole (HYFLON® AD60) and two perfluoropolyethers (PFPEs) containing ammonium phosphate or triethoxysilane functionalities, FLUOROLINK® F10 and FLUOROLINK® S10 respectively, have been evaluated as protective coatings that can be easily applied on anodized titanium surfaces. Water and n-dodecane contact angle measurements have been recorded by using the sessile drop method for bare and coated surfaces in order to determine the hydrophobic and oleophobic properties of the coatings. The UV-stability of coatings have been studied by Fourier transform infrared spectroscopy (FT-IR) analyses and by observing the variation of water contact angles on coated substrates before and after UV irradiation at regular time intervals. The thickness of the fluorinated films has been measured by ellipsometry and by weight evaluation. Preliminary tests of the adhesion between films and substrate have been conducted.

Functionalization of colloidal particles based on the use of polyelectrolytes and heterocoagulation was combined with electrophoretic deposition (EPD), with the aim of depositing titania-polystyrene (TiO2-PS) composite particles on Ti6A14V substrates. The composite particles were obtained by heterocoagulation of TiO2 nanoparticles on the surface of monosized polystyrene beads of 4.6 mu m in diameter. Two alternative methods were developed for the preparation of the TiO2-PS suspensions in organic fluids for cathodic electrodeposition. The first method was carried out in alkaline aqueous medium with the use of polyelectrolytes and intermediate control measurements of zeta potential, conductivity, and pH; the second one was carried out directly in the organic solvent used for EPD, typically isopropanol. Examples of deposits obtained by EPD in both suspensions and a comparative analysis between the two methods are presented. (c) 2007 Elsevier Inc. All rights reserved.

The behaviour of suspended AI 2 O 3 nanoparticles in a tribocorrosion system was experimentally investigated. The test configuration involved an alumina ball rubbing against a stainless steel plate in a reciprocating motion wear test rig. The contact was immersed in an acetate buffer solution with or without nanoparticles. The stainless steel plate was kept under controlled potential and the anodic current was measured using a three-electrode electrochemical set up. The evolution of friction and wear (vertical contact displacement) during rubbing were continuously measured. The presence A1 2 O 3 nanoparticles lowered significantly the extent of metallic wear and reduced friction. The observed close correlation among the variations of current, friction and vertical displacement indicates that the nanoparticles act as lubricant by forming a third body protecting the metal.

A new stabilizer for fluorinated lubricants, either oils or greases, was developed stemming from the chemistry of perfluoropolyethers. The additive shows good efficiency in improving the stability of perfluoropolyether oils at very high temperatures in presence of metals and under oxidative environments, extending thus the life of the formulated lubricants. Some specific tests were carried out in order to assess performances in applications. Furthermore, as a first approach, grazing infrared reflection-absorption spectroscopy was used as a probe for studying structural and topological issues relative to additive-surface interactions.Copyright © 2005 by ASME

The thermal reactivity of a set of different blocked perfluoropolyether (PFPE) containing polyisocyanates and one monocomponent polyurethane containing a PFPE diol was investigated by Fourier transform infrared (FT-IR) spectroscopy. With the former series of products the deblocking kinetics at 90 degrees C and 120 degrees C were investigated with time-dependent spectral data, showing the highest thermal deblocking activity for 3,5 dimethylpyrazole blocking agent. The crosslinking reaction of the PFPE diol with ketoxime blocked isocyanurate at 150 degrees C was monitored by infrared (IR) spectroscopy and two-dimensional (2D) correlation analysis; the results suggested a prevailing direct condensation mechanism and the formation of urea byproducts in the later stages of reaction. Both synchronous and asynchronous spectra were considered and discussed, pointing out the time relation of the chemical functions during the crosslinking experiment.

This study investigates the microvascular permeability changes in tracheal tissue of rats exposed to hyperbaric oxygen (HBO). Rats, following exposure to HBO or ambient air (control animals) for 1.5, 3 and 6 h, were prepared for recording of nitric oxide exhaled (FENO) in air using a chemiluminescence analyser. The level of FENO was not statistically different in the two groups. Plasma exudation, evaluated by measuring the leakage of Evans blue (EB) dye into the tracheal tissue, was significantly elevated (48, 86 and 105% at 1.5, 3 and 6 h, respectively) in HBO-treated rats. Plasma exudation in the trachea of control rats was significantly increased (42%, P0.05) by NG-nitro-L-arginine methyl ester (L-NAME), whereas it was significantly reduced (31%, P0.05) in rats exposed to HBO for 3 h. N-acetylcysteine (NAC) and flunisolide significantly prevented the increase in plasma leakage in HBO-treated rats. In contrast, indomethacin was devoid of anti-exudative activity in these experiments. Western immunoblot showed a significant increase in the level of inducible nitric oxide synthase (iNOS) protein in the tracheal homogenates of HBO-treated rats, as compared to basal levels. These results indicate that nitric oxide (NO) is involved in the maintenance of microvascular permeability in tracheal tissue of rats. The protective effect observed with the steroid seems to support this hypothesis. Furthermore, the beneficial action of NAC underlines that reactive oxygen species participate in the microvascular permeability changes observed in tracheal tissue of rats exposed to HBO.

Hemolytic Disease of the Newborn (HDN) can be a life threatening condition in Rh D positive babies born from Rh D negative mothers. For several decades, prophylactic treatment with immunoglobulins derived from human blood plasma from immunized donors has been available. Because of concerns for donor safety and limited supply of raw material, alternatives for production of specific immunoglobulins were investigated. Since 1994 ZLB has, in collaboration with a group at the University Hospital in Bern, started to develop recombinant anti-D antibodies. In 1997, a multidisciplinary team with expertise ranging from molecular biology to biochemical engineering for large scale operations was constituted, co-funded by the Swiss National Science Foundation and ZLB, as the industrial partner. The aims of this team are to establish the prophylactic principle and the manufacturing process for anti-D therapy based on recombinant antibody preparations produced from Chinese hamster ovary (CHO) cells.

Rats were exposed to hyperbaric oxygen (HBO = 100% oxygen; 2.5 atmospheres absolute pressure) for 6 h. Isovolumic left heart preparations from these animals were subjected to global low flow-ischemia (perfusion rate from 12 ml/min to 2 ml/min for 40 min) and reperfusion. Hearts from rats not exposed to HBO underwent the same ischemic-reperfusion procedure (controls). As compared to control, HBO treatment caused in ex vivo hearts a significant aggravation of cardiac ischemic picture as indicated by a marked increase in left ventricular end diastolic pressure (LVEDP) and reduced post ischemic left ventricular developed pressure (LVDP). At the end of the ischemic and reperfusion periods LVEDP values were 6.8 (p0.001) and 8 (p0.001) times higher than the corresponding control values. Moreover, LVDP and coronary perfusion pressure (CPP) values were decreased (2.8 times; p0.001) and increased (56%; p0.001), respectively, as compared to control preparations. These events were also associated with a considerable impairment of the cardiac tissue to generate 6-keto-PGF1 alpha. Treatments of rats with different doses of acetylcysteine (N-acetylcysteine, CAS 616-91-1, NAC; 0.25-0.5-1 g/kg p.o.) before HBO displayed a clear-cut and dose-related protective activity in hearts subjected to ischemia-reperfusion. Also the generating capacity of 6-keto-PGF1 alpha from these hearts were restored according to the dose of NAC employed. When aortic rings from rats exposed to HBO were considered, they showed a reduced capacity to release 6-keto-PGF1 alpha and an increased sensitivity to endothelin-1. At the same time, the relaxant activity of acetylcholine in these tissues was almost lost. Again, NAC treatment of the animals before HBO restored in a dose-dependent way the capacity of the aortic rings to generate 6-keto-PGF1 alpha. This event was paralleled by normalized responses of the preparations to endothelin-1 and acetylcholine. Taken together these results clearly indicate that acute HBO treatment of the rats markedly aggravates the ischemic-reperfusion damage in ex vivo hearts. This event is coupled with a compromised integrity of cardiac and extracardiac endothelial cell functions. The protective activity of NAC observed in this study once more emphasises its therapeutic role in increasing antioxidant defence mechanisms.

Chilling injury is commonly observed in many species of tropical and subtropical origin [1, 2]. The critical temperature for chilling injury is usually between 0 and 10°C, but it depends on species, developmental stages, organs and tissues [1, 2]. Damage increases with exposure time, however a feature of this phenomenon is its reversibility following short exposure to low temperature [3].

Myotonic dystrophy (DM) is a well-defined autosomal dominant disorder characterized by myotonia, muscle weakness, cardiac conduction defects, cataracts, and endocrine abnormalities. Recently a newly recognized disorder, similar to but distinct from DM, has been observed with multisystem findings including intermittent myotonia, proximal myopathy, and occasional cardiac conduction disturbances. This disorder has been called proximal myotonic myopathy (PROMM). No history of anticipation is present and there is no linkage to the gene locus for DM or to the loci for the muscle sodium or chloride channels. This report describes a family with a normal size of the CTG trinucleotide repeat expansion of the DM gene in which affected individuals have myotonia (intermittent, exacerbated by cold), bilateral cataracts, mild hypogonadism and mild temporal atrophy. Affected individuals also have proximal muscle weakness, facial involvement, nonspecific abnormalities on muscle biopsy, normal cardiac conduction, and no glucose intolerance. The absence of trinucleotide repeat expansion in the DM gene is consistent with this family being affected by a disorder distinct from DM, possibly a form of PROMM.