Znanstvena istraživanja u 21. stoljeću - etički aspekti uporabe laboratorijskih životinja i alternativni modeli

U toksikološkim istraživanjima uz uporabu klasičnih (in vivo) istraživanja, primjenjuju se alternativni test sustavi. Korištenje laboratorijskih životinja, embrija, humanog i animalnog tkiva, kultura stanica i fetalnog seruma u istraživanjima smatra se etički problematičnim te se ograničava zakonima, pravilnicima i praksom. Razmatranjem načina kojima bi se neetičnost mogla izbjeći, došlo je do razvoja “3R” načela (akronim za tri pristupa koja bi se trebala provoditi pri istraživanjima na laboratorijskim životinjama), a to su: smanjenje/racionalizacija uporabe laboratorijskih životinja (engl. Reduction), načelo njihove zamjene (engl. Replacement) i poboljšanje uvjeta uzgoja, smještaja i skrbi za životinje (engl. Refinement). Većina je alternativnih testova toksičnosti još uvijek u postupku validacije. Pojedini in vitro testovi za istraživanja embriotoksičnosti (etički posebno osjetljivo područje) koja su priznala nadležna regulatorna tijela, su EST (engl. Embryonic Stem cell Test), WEC (engl. Whole- Embryo Culture) i MM (engl. MicroMass) test. Standardizacija protokola i uvođenje novih in vitro modela predstavlja važan segment napretka u toksikološkim istraživanjima. Znanstvena budućnost tu vidi mogućnost razvoja i implementacije načela etičnosti u istraživanja primjenjujući sustave koji će promišljeno i bez korištenja živih organizama dijelom nadomjestiti metode u biomedicini, veterinarskoj medicini, biotehnologiji i užem smislu - toksikologiji i farmakologiji.

The efficiency of chitosan-graphene oxide composite membranes modified with genipin in fuel cell application

The paper reports on the processing of chitosan N-doped reduced graphene oxide (CS/N-rGO) nanocomposite membranes prepared by a facile, dispersion-casting procedure aimed as anion exchange membranes in fuel cells. Genipin (GEN) was used as a crosslinking agent to ameliorate mechanical weakens of nanocomposite membranes, while the N-rGO filler, aside of its role as a mechanical enhancer, is expected to improve the ionic conductivity of membranes. The resulting properties of processed membranes in terms of morphology, tensile strength, elasticity, and ethanol permeability were examined. The relevance of the membranes in terms of efficiency and performance was demonstrated in a single cell test.

Diagnosis of Hypersensitivity Induced by Antituberculosis Drugs

Objective. To explore the clinical value of the specific plasma cell detection and specific T lymphocyte detection test in diagnosing hypersensitivity caused by antituberculosis drugs. Methods. A total of 266 patients with pulmonary tuberculosis who developed hypersensitivity during the treatment of primary pulmonary tuberculosis in our hospital and 266 patients without hypersensitivity during the treatment of pulmonary tuberculosis in our hospital were selected as the control group. The admission time is from January 2013 to June 2020. The specific plasma cell test and specific T lymphocyte test were used as the criteria to determine which drugs induced hypersensitivity, and the diagnostic value of these two methods in the diagnosis of hypersensitivity induced by four first-line antituberculosis drugs (isoniazid (INH), ethambutol (EMB), rifampicin (RFP), and pyrazinamide (PZA)) was analyzed. Results. The sensitivity of the specific plasma cell test in the diagnosis of hypersensitivity induced by INH, EMB, RFP, and PZA was 63.42%, 51.20%, 47.81%, and 56.37%, respectively, and the specificity was 95.33%, 99.87%, 96.52%, and 99.99%, respectively. The sensitivity of the specific T lymphocyte test in the diagnosis of hypersensitivity induced by INH, EMB, RFP, and PZA was 66.47%, 52.88%, 49.91%, and 58.54%, respectively, and the specificity was 97.28%, 99.99%, 98.38%, and 100.00%, respectively. Conclusion. The specific plasma cell test and specific T lymphocyte test have high specificity in the diagnosis of hypersensitivity caused by antituberculosis drugs, and the specific T lymphocyte test is better than the specific plasma cell test. It is of great significance to guide the clinical application of antituberculosis drugs.

Incorporating Kinetic Modeling in the Development Stages of Hard Rock Mine Projects

Weathering cell test, designed specifically to overcome material-limited constraints, yields prompt and efficient experimental assessment during the development stages of mining projects. However, it has barely benefited from geochemical modeling tools despite their ease of use. Accordingly, this paper aims to strengthen the upstream geochemical assessment via parametric analysis that simulates the effect of various mineral assemblages on leachate quality recovered from weathering cells. The main objective is to simulate the pH in presence of silicate neutralizing minerals and Mn release from carbonates based upon minimal characterization data. The public domain code PHREEQC was used for geochemical kinetic modeling of four weathering cells. The kinetic model utilized a water film concept to simulate diffusion of chemical elements from mineral surfaces to the pore water. The obtained results suggest that the presence of the silicate neutralizing minerals slightly affects the Mn release from carbonates. Furthermore, plagioclases could supply a significant neutralization potential when they predominate the mineral assemblage. Finally, coupling weathering cell test and parametric analyses illuminate the pH evolution for various mineral proportion scenarios.

“Structural Audit of an Old Building” (A Case Study)

In India there are infinite old structures that are at the verge of damages. There are many buildings which have reduced their strength due to time passes, due to deterioration of concrete from structural element, due to development of cracks. The structure is a combination of load carrying members, damages in members cause failure of structure and it is harmful for living beings. To prevent old structure from failure the technique is adopted know as Non-Destructive Testing (NDT). With the help of non-destructive testing auditing of an old structure is get easier. NDT examine the total health of an infrastructure in order to check strength and stability of building. NDT is a bunch of various testing consist of Ultrasonic pulse velocity test (UPV), Rebound hammer test (RHT), Half-cell test, etc. Conducting NDT on building and analyzing testing result decide to repair building as per IS code, technique like grouting, Retrofitting, etc. to increase strength and stability of building. In this project structural has to be done on old structure which is situated at Nagpur. Audit done by NDT consist of Ultra-sonic pulse velocity test, Rebound hammer test, Half-cell test. After analyzing all test result including visual inspection it is found that structure need to repair and retrofitted to make it safe and stable for all static loadings. Column jacketing also provide to structure.

Prognostic factors of esophageal perforation and rupture leading to mortality: a retrospective study

Background Esophageal perforation and rupture (EPR) is a serious, potentially life-threatening condition. However, no treatment methods have been established, and data concerning factors affecting mortality are limited. This report presents the prognostic factors of mortality in EPR based on experience in the management of such patients. Methods For this retrospective analysis, 79 patients diagnosed as having EPR between 2006 and 2016 and managed at Gyeongsang National University Hospital were examined. The management method was determined in accordance with the location and size of the EPR, laboratory findings, and radiological findings. Thirty-nine patients were treated with surgery; and 40, with nonsurgical management. Results The most common cause of EPR was foreign body (fish bone or meat bone), followed by vomiting, iatrogenic causes, and trauma. Thirty-nine patients underwent primary repair of EPR, of whom 4 patients died. Forty patients underwent nonsurgical management, of whom 3 patients died. The remaining patients were discharged. Mortality correlated with the size of the EPR (> 25 mm) and the segmented neutrophil count percentage (> 86.5%) in the white blood cell test and differential. Conclusions The mortality risk was increased when the EPR size and the segmented neutrophil count percentage in the white blood cell test and differential was high. Delayed diagnosis, which was considered an important predictive factor in previous investigations, was not statistically significant in this study. Trial registration: Not applicable.

Influence of Wetting Additive Based on C12 - C14 Alkyl Ester Sulphate with Essential Oils on the Quality of Nickel Coating

The influence of wetting additive based on C12 - C14 alkyl ester sulfate with essential oils on the quality of nickel coatings is examined in the paper. The additive was tested at different concentrations added to the base electrolyte, taking the following concentrations: the concentration recommended twice lower (C1); lower recommended concentration (C2); upper recommended concentration (C3); the concentration twice higher compared to the lower recommended (C4) and the concentration twice higher compared to the upper recommended (C5). The value of the surface tension of the solution was determined, and the corrosion resistance in the salt chamber was examined. In addition, what is important in the production itself is the visual appearance of the coating, which was determined using the Hull cell test. The additive has been proven to be effective in reducing the surface solutions, which directly affects the production of nickel coatings of better quality and aesthetic appearance.