The work presents monitoring of the corrosion rate for pure magnesium and the binary magnesium alloy Mg72Zn28. Alloying elements with a purity of 99.9% were used. The melting was performed under the ...protection of inert gas - argon in an induction furnace. The liquid alloy was poured into a copper mold. In order to make amorphous ribbons, the obtained samples in the form of rods were re-melted on a melt spinner machine. The next step was to perform corrosion tests in Ringer's solution. Corrosion tests were carried out at a temperature of 37°C and pH 7.2. The purpose of using Ringer's solution was to recreate the conditions for the body fluids of the human body. The use of the following research methods, such as: OCP (open circuit potential), LSV (linear sweep voltammetry) and EIS (electrochemical impedance spectroscopy), was aimed at determining the corrosion resistance of the tested materials. Tests carried out in Ringer's solution showed that pure magnesium has significantly worse corrosion resistance than the binary Mg72Zn28 alloy. The conducted research also confirmed that the cathodic reaction takes place faster on the surface of amorphous ribbons. It was also confirmed that for both crystalline materials there is diffusion of chloride ions through the corrosion product layer. SEM-EDS tests were performed on the surface of an amorphous ribbon of the Mg72Zn28 alloy after corrosion in Ringer's solution.
The aim of this study was to investigate the influence of different process parameters as chemical composition, the pH value and immersion time on the corrosion of the some TiMoNb alloys, using ...different electrochemical techniques such as: cyclic voltammetry, open circuit potential (OCP) measurement, polarization curves and electrochemical impedance spectroscopy (EIS). The alloys were analyzed in the natural pH of the Ringer solution, but also with an acidic modification of the solution (ph = 4) and a basic modification (ph = 8). The more acidic values of pH, the more evident are differences between corrosion behavior of titanium-based alloys depending on their chemical compositions and immersion times.
•TiO2 films deposited onto MgCa4Zn1Gd1 alloy have an anatase structure.•The film applied using magnetron sputtering is electrochemically resistant.•TiO2 deposited by spin coating decreases the ...corrosion rate of Mg-based alloy.
Recently, magnesium and its alloys have been investigated as potential candidates for orthopedic implants, due to their numerous beneficial mechanical properties. Nevertheless, magnesium is characterized by its poor corrosion resistance in chloride-rich environment, present in the human body. Unfortunately, this major disadvantage limits the biomedical applications of magnesium alloys. The corrosion rate of these materials can be decreased with the use of oxide films (e.g. ZnO, TiO2, MgO).
In the article, a comparison was conducted, with regard to the structure and corrosion behavior of TiO2 films, with the thickness of about 300 nm, deposited onto MgCa4Zn1Gd1 alloy by magnetron sputtering and spin coating methods. The structure observations of the oxide films in scanning electron microscopy are also presented. The phase analysis using X-ray diffractometer and structure identification using the Raman spectrometer are also shown. Moreover, the paper also includes a discussion on the topography observations and roughness measurements in atomic force microscopy. The results of the potentiodynamic and immersion tests of corrosion resistance of TiO2 films in Ringer's solution at 310.15 K are also presented.
The analysis of investigation results shows that both of the studied films have an anatase structure. The surface of TiO2 applied using the magnetron sputtering method is characterized by smaller and more uniform grains, compared to the film applied via spin coating. TiO2 applied using the physical vapor deposition method has a slightly higher electrochemical corrosion resistance. The results of immersion tests have shown, that the alloy with TiO2 film deposited by sol-gel is more resistant to corrosion.
Background and aims
Previous studies have suggested that aggressive hydration with lactated ringer solution are one of the protective factors in preventing post endoscopic retrograde ...cholangiopancreatography (post-ERCP). We conducted a systematic review and meta-analysis to examine the efficacy aggressive hydration with lactated Ringer solution in preventing PEP.
Methods
All published and unpublished articles on aggressive hydration with lactated ringer solution in those underwent ERCP procedure for any reasons were screened for eligibility. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. This paper doesn’t need the IRB approval.
Results
Seven RCTs met the inclusion criteria. Meta-analysis indicates that aggressive hydration with lactated Ringer solution were associated with lower PEP rate.odds ratio (OR) 0.29; 95% confidence interval (CI) 0.18–0.48; lower incidence of hyperamylasemia (OR 0.49; 95% CI 0.35, 0.69) and lower risk of pain (OR 0.28; 95% CI 0.10–0.81). The association between aggressive hydration with lactated Ringer solution and incidence of moderate severity PEP were unclear (OR 0.57; 95% CI 0.22, 1.45). Sensitivity analyses also showed that omitting 1 study from analysis of PEP rate could reduce the heterogeneity but did not change the conclusion of this meta-analysis. A cumulating meta-analysis was performed statistically which showed a stable result of overall incidence of PEP.
Conclusions
Aggressive hydration with lactated Ringer solution was a protective factor in reducing the overall incidence of PEP, hyperamylasemia and risk of abdominal pain.
Biomaterials should be thoroughly studied in order to make sure they do not cause any harm to the human body. Considering that biocompatibility is very strict, the material must be non-toxic, and not ...cause any allergies or inflammation in the body. Of the different categories of metallic biomaterials, the cobalt-based alloys are among the preferred options. Applications can be found in orthopedic implants, and both cardiac and dental fields. Co–Cr alloys have been used in dentistry for porcelain-fused-to-metal (PFM) crowns due to their biocompatibility, wear resistance, long service duration, good mechanical properties, and last but not least, superior resistance to corrosion. The present investigation evaluated and compared two Co–Cr based dental alloys, studying their microstructural characterization and corrosion behavior in Ringer solution, using various techniques. Findings in this investigation revealed a high passivation tendency for the two alloys studied, with the formation of mixed protective layers Cr2O3·CoO with high stability on their surfaces, which substantially improves their biocompatibility in Ringer solution. The kinetic parameters of the corrosion process in the experiment indicated a two-time constants process with an anodic control, attributable to the formation of passive films on their surfaces. According to the results obtained in this investigation, the polarization resistance of the two Co–Cr alloys examined in Ringer solution reached the values of biomaterials with a high resistance to corrosion, and the passive films formed on their surface had a more than appropriate resistance to corrosion.
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•The behavior of two Co–Cr dental alloys in Ringer solution was investigated.•Both alloys tend to passivate and this passivation tendency is very high.•The alloys present the formation of a mixed protective layer Cr2O3·CoO.•The high stability of passive film substantially improves their biocompatibility.
Refrigerated preservation is a simple and inexpensive method for the short‐term preservation of fish sperm used in the hatchery. The type of extender is an important factor that determines the nature ...of the preservation conditions because certain extenders are better suited for preserving sperm obtained from specific species. Therefore, this study aims to determine the best type of extender for the refrigerated preservation of sperm obtained from climbing perch (Anabas testudineus). The study was conducted using three replications of five types of extenders, which include Alsever's solution, urea solution, Ringer solution, physiological NaCl and glucose‐base. Subsequently, the sperm was diluted with each extender at a sperm‐extender dilution rate (v/v) of 1:60, stored at 4°C and assayed every 24 h for 6 days to determine the sperm quality. The results showed that the type of extender had a significant effect on the sperm motility, viability and fertilization rates of climbing perch after refrigerated preservation (p < 0.05). Also, the highest values of motility, viability and fertilization rates from the sperm diluted with glucose‐base were 45.83%, 43.83% and 46.28%, respectively, which were significantly different from other treatments. Therefore, the glucose‐base was the best extender for the refrigerated preservation of climbing perch (A. testudineus) sperm in comparison to others extender used.
As shown in studies, aggressive hydration during the perioperative period of endoscopic retrograde cholangiopancreatography (ERCP) effectively prevents post-ERCP pancreatitis (PEP). We conducted a ...systematic review and meta-analysis to evaluate the clinical effectiveness and safety of aggressive hydration with lactated Ringer solution at preventing PEP.
We searched all relevant research from PubMed, the Cochrane Library, Embase, the Web of Science, ClinicalTrial.gov, and Scopus database for randomized controlled trials (RCTs) published before March 2017. Reference lists from reviews or relevant articles were screened for RCTs. The primary outcomes were the incidence of PEP and the incidence of moderate to severe pancreatitis. The secondary outcomes were the incidence of hyperamylasemia and pain and the length of hospital stay. The meta-analysis was conducted using the Cochrane Program Review Manager.
Three RCTs were included in our study. On the basis of the results of the meta-analysis, the aggressive hydration group had a lower incidence of pancreatitis after ERCP odds ratio (OR)=0.29; 95% confidence interval (CI), 0.16-0.53; a lower incidence of moderate to severe PEP (OR=0.16; 95% CI, 0.03-0.96); lower incidence of hyperamylasemia (OR=0.38; 95% CI, 0.25-0.59); lower risk of pain (OR=0.17; 95% CI, 0.08-0.38); and a shorter duration of hospital stay (standardized mean difference=-0.41; 95% CI, -0.69 to -0.14).
Aggressive hydration with lactated Ringer solution can reduce the overall incidence of PEP, moderate to severe pancreatitis and hyperamylasemia, shorten the length of hospitalization and reduce pain.
The paper presents the results of experimental strength tests of specimens made of two commercially available bone cements subjected to compression, that is a typical variant of load of this material ...during use in the human body, after it has been used for implantation of prostheses or supplementation of bone defects. One of the factors analysed in detail was the duration of cement seasoning in Ringer’s solution that simulates the aggressive environment of the human body and material degradation caused by it. The study also focused on the parameters of quantitative deviation from the recommended proportions of liquid (MMA monomer, accelerator and stabiliser) and powder (PMMA prepolymer and initiator) components, i.e., unintentional inaccuracy of component proportioning at the stage of cement mass preparation. Statistical analysis has shown the influence of these factors on the decrease in compressive strength of the cements studied, which may be of significant importance in operational practice.
•Tribocorrosion of titanium alloy in a body fluid was performed.•A pin-on-flat reciprocating sliding tribo-electrochemical setup was built.•Sliding speed plays a major role in metal loss at pure ...mechanical wear.•The wear track in tribocorrosion showed a homogeneous roughness.•Synergistic factor was higher for the highest applied load condition.
The tribocorrosion behavior of a biocompatible ASTM-F67Gr1 titanium alloy was evaluated. An experimental pin-on-flat reciprocating sliding tribo-electrochemical setup was built which allowed the investigation of tribocorrosion phenomena in an electrolyte of a Ringer solution. Tests were performed at anodic and cathodic potential, and at two values of applied load and sliding speed. Potentiodynamic tests indicated a corrosion potential of −0.368±0.082VSCE and a passivation range between 0.344VSCE and 2.932VSCE was observed. After polarization tests, no pits were identified on the titanium alloy. The volume of worn material was higher at an anodic potential than in a cathodic potential, especially for the condition of the highest applied load and speed. Higher metal losses at a cathodic potential (pure mechanical wear) were observed in conditions of the highest speed. The mass loss due to the corrosion was similar for all conditions, and the synergistic factor was the highest for the condition of the highest applied load and sliding speed.
BACKGROUND:Pancreatitis is the most common complication of endoscopic retrograde cholangiopancreatography (ERCP). The results of previous studies evaluating aggressive hydration with lactated Ringer ...solution for reducing the incidence of post-ERCP pancreatitis (PEP) are inconsistent.
AIM:We performed a meta-analysis to determine whether aggressive hydration with lactated Ringer solution reduced PEP.
METHODS:Randomized controlled trials (RCTs) comparing aggressive hydration with standard hydration with the same lactated Ringer solution for prophylaxis of PEP were searched in PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and CINAHL databases. ClinicalTrial.gov and International Standard Randomised Controlled Trial Number registry were also searched for unpublished studies. A meta-analysis was conducted in accordance with the Cochrane Handbook for Systemic Reviews of Intervention.
RESULTS:A total of 7 RCTs with 1047 participants were included into this meta-analysis. Meta-analysis showed that aggressive hydration reduced the incidence of PEP as compared with standard hydration odds ratio (OR), 0.47; 95% confidence interval (CI), 0.30-0.72; P=0.0006. Aggressive hydration also reduced the incidence of post-ERCP hyperamylasemia as compared with standard hydration (OR, 0.38; 95% CI, 0.25-0.59; P<0.00001). No difference of adverse effects was found between aggressive hydration and standard hydration (OR, 0.48; 95% CI, 0.15-1.57; P=0.23). Sensitivity analyses showed that neither alternative effect measures nor statistical models regarding heterogeneity affected the conclusions of this meta-analysis. Sensitivity analyses also showed that omitting 1 study from analysis did not change the conclusion of this meta-analysis.
CONCLUSIONS:On the basis of this meta-analysis of RCTs, aggressive hydration with lactated Ringer solution is an effective and safe therapy for prophylaxis of PEP.
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