Oxidation of Cellular Amino Acid Pools Leads to Cytotoxic Mistranslation of the Genetic Code

Aminoacyl-tRNA synthetases use a variety of mechanisms to ensure fidelity of the genetic code and ultimately select the correct amino acids to be used in protein synthesis. The physiological necessity of these quality control mechanisms in different environments remains unclear, as the cost vs benefit of accurate protein synthesis is difficult to predict. We show that in Escherichia coli, a non-coded amino acid produced through oxidative damage is a significant threat to the accuracy of protein synthesis and must be cleared by phenylalanine-tRNA synthetase in order to prevent cellular toxicity caused by mis-synthesized proteins. These findings demonstrate how stress can lead to the accumulation of non-canonical amino acids that must be excluded from the proteome in order to maintain cellular viability

Non-Invasive Indirect Biochemical Markers for Liver Fibrosis

Liver fibrosis may be due to a variety of chronic liver diseases and may occur as a result of the healing process of liver damage. Although liver biopsy is accepted as the gold standard method in diagnosis and follow-up of patients with fibrosis currently, due to the serious complications like severe pain, internal bleeding, pneumothorax, and rarely death and even fault in the diagnostic accuracy like sampling error, various assessments by different pathologists and even by the same pathologist, interest in alternative methods is increasing day by day. In the light of these improvements, many studies have been performed on indirect non-invasive biochemical markers that can be used instead of liver biopsy, in the last decade. APRI, Forns index, FIB-4, AST-ALT ratio, age-platelet index, hepascore, fibrotest, fibroindex, fibrometer and fibrosis index are the most commonly used ones of these tests. While having some advantages like ease of accessibility, low complication rate, and lower costs, these tests cannot be used as the gold standard method due to the unsatisfactory diagnostic accuracy values. However, these indices have a high diagnostic value especially in the diagnosis and exclusion of significant fibrosis (METAVIR F2-4) and cirrhosis (METAVIR F4). [Archives Medical Review Journal 2014; 23(3.000): 427-442

The relationship between cognitive impairment and fatty acids and carnitine in hemodialysis patients

Background/Aim: The prevalence of cognitive impairment (CI) is high in hemodialysis patients. In this study, the relationship between CI and serum carnitine, plasma omega-3, omega-6 and omega-3/omega-6 fatty acid ratio was evaluated in hemodialysis patients. Materials and methods: Sixty two patients [male: 40 (64.5%), mean age 51 ±13 years] were included in this cross-sectional study. Serum total and free-carnitine levels were determined by ELISA. Plasma omega-3 [eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA)] and omega-6 [arachidonic acid (AA), dihomo gamma linoleic acid (DGLA)] levels were measured using LC-ESI-MS/MS. According to the Montreal Cognitive Assessment (MoCA) scores, ≤24 points were considered as CI. MoCA score ≤24 and >24 were determined as Group 1 and Group 2, respectively. Results: Group 1 had significantly higher AA + DGLA/EPA + DHA ratios and lower free-carnitine, DHA and EPA + DHA levels compared to Group 2 (P = 0.008, P = 0.040, P = 0.032, P = 0.032, respectively). Group 1 had a statistically lower education level (P 24 se determinaron como grupo 1 y grupo 2, respectivamente. Resultados: El grupo 1 tenía proporciones de AA + DGLA/EPA + DHA significativamente más altas y niveles más bajos de carnitina libre, DHA y EPA + DHA en comparación con el grupo 2 (p = 0,008, p = 0,040, p = 0,032 y p = 0,032, respectivamente). El grupo 1 tenía un nivel educativo estadísticamente más bajo (p < 0,05). Se descubrió una correlación negativa entre las puntuaciones de MoCA y las proporciones AA + DGLA/EPA + DHA (rs = −0,284, p = 0,026). Los niveles de carnitina libre se correlacionaron positivamente con los niveles de EPA y EPA + DHA (rs = 0,278, p = 0,030, y rs = 0,271, p = 0,034, respectivamente), y negativamente con las proporciones AA + DGLA/EPA + DHA (rs = −0,414, p = 0,001). En el análisis de regresión logística multivariante las puntuaciones de MoCA se asociaron con las proporciones AA + DGLA/EPA + DHA (p = 0,009) y con el nivel educativo (p < 0,001). Conclusión: Se determinó que una alta relación AA + DGLA/EPA + DHA y un bajo nivel educativo podrían ser factores de riesgo independientes del CI. Se ha demostrado que el nivel de carnitina libre puede tener efectos positivos en las distribuciones plasmáticas de EPA + DHA y AA + DGLA. Los niveles bajos de ácidos grasos omega-3 pueden estar asociados con el CI en pacientes en hemodiálisis, y los niveles bajos de carnitina pueden contribuir parcialmente a este proceso. Además, los programas de educación cognitiva pueden tener un efecto en la prevención del CI en pacientes en hemodiálisis con bajos niveles educativos

Adding stewed apricot juice to senna improves quality of colon cleansing in preparation for colonoscopy

Background: To achieve optimal colonoscopic examination, the bowel must be sufficiently cleansed. However, none of the currently available colonoscopy preparation regimens is safe, efficient, and comfortable. The aim of this study was to determine whether adding stewed apricot juice to senna increased patient comfort and improved bowel cleansing during colonoscopy preparation. Methods: Outpatients of both genders who were over 18 years old and were referred for elective colonoscopy were randomly allocated to drink stewed apricot juice with senna or senna by itself. The quality of the colon cleansing was evaluated using the Ottawa scale. Patient tolerance and adverse events were evaluated through the completion of a questionnaire. Results: The study included a total of 128 patients in the randomization procedure. A significantly greater cleansing effect was observed using stewed apricot juice plus senna in the right and transverse colon (p = 0.038, p = 0.037 respectively). It was also determined that in the stewed apricot juice plus senna group, overall cleansing was superior (p < 0.001), total colonoscopy (17.6 min vs. 22.8 min, p = 0.048) and cecal intubation (7.4 min vs. 11.2 min, p = 0.042) times were shorter, and the colonoscopy procedure was easier (79.4% vs. 49.2%, p < 0.001). No differences were observed between the groups with respect to patient acceptance, compliance, and adverse events. In the stewed apricot juice plus senna group, 91.2% of patients stated their willingness to receive the same regimen in the future compared to 80% of the patients in the senna alone group (p = 0.037). Conclusion: The addition of natural, stewed apricot juice to senna significantly improves cleansing outcomes without additional adverse effects