Nitroxides are stable radicals consisting of a nitroxyl group, >N-O•, which carries an unpaired electron. This group is responsible for the paramagnetic and antioxidant properties of these compounds. A recent study evaluated the effects of pyrrolidine and pyrroline derivatives of nitroxides on the antioxidant system of human red blood cells (RBCs). It showed that nitroxides caused an increase in the activity of superoxide dismutase (SOD) and the level of methemoglobin (MetHb) in cells (in pyrroline derivatives) but had no effect on the activity of catalase and lactate dehydrogenase. Nitroxides also reduced the concentration of ascorbic acid (AA) in cells but did not cause any oxidation of proteins or lipids. Interestingly, nitroxides initiated an increase in thiols in the plasma membranes and hemolysate. However, the study also revealed that nitroxides may have pro-oxidant properties. The drop in the AA concentration and the increase in the MetHb level and in SOD activity may indicate the pro-oxidant properties of nitroxides in red blood cells.

UNASSIGNED: To explore the predictive factors and predictive model construction for the progression of prostate cancer bone metastasis to castration resistance.
UNASSIGNED: Clinical data of 286 patients diagnosed with prostate cancer with bone metastasis, initially treated with endocrine therapy, and progressing to metastatic castration resistant prostate cancer (mCRPC) were collected. By comparing the differences in various factors between different groups with fast and slow occurrence of castration-resistant prostate cancer (CRPC). Kaplan-Meier survival analysis and COX multivariate risk proportional regression model were used to compare the differences in the time to progression to CRPC in different groups. The COX multivariate risk proportional regression model was used to evaluate the impact of candidate factors on the time to progression to CRPC and establish a predictive model. The accuracy of the model was then tested using receiver operating characteristic (ROC) curves and decision curve analysis (DCA).
UNASSIGNED: The median time for 286 mCRPC patients to progress to CRPC was 17 (9.5-28.0) months. Multivariate analysis showed that the lowest value of PSA (PSA nadir), the time when PSA dropped to its lowest value (timePSA), and the number of BM, and LDH were independent risk factors for rapid progression to CRPC. Based on the four independent risk factors mentioned above, a prediction model was established, with the optimal prediction model being a random forest with area under curve (AUC) of 0.946[95% CI: 0.901-0.991] and 0.927[95% CI: 0.864-0.990] in the training and validation cohort, respectively.
UNASSIGNED: After endocrine therapy, the PSA nadir, timePSA, the number of BM, and LDH are the main risk factors for rapid progression to mCRPC in patients with prostate cancer bone metastases. Establishing a CRPC prediction model is helpful for early clinical intervention decision-making.

2-Hydroxyglutarate (2HG) is an oncometabolite that can contribute to tumor progression. Two enantiomer forms, L-2HG and D-2HG, arise from independent pathways starting from the precursor α-ketoglutarate (αKG). L-2HG production occurs through the promiscuous activities of malate dehydrogenase (MDH) and lactate dehydrogenase (LDH) under acidic and/or hypoxic conditions. D-2HG frequently accumulates by gain-of-function mutations in the genes encoding two isoforms of isocitrate dehydrogenase (IDH1 and IDH2). Cognate metabolite repair enzymes, L- and D-2-hydroxyglutarate dehydrogenases, oxidize the enantiomers and cause abnormally high 2HG accumulation and disease when mutated. Elevated levels of either oncometabolite affect redox homeostasis, metabolism, and immune system functioning. Moreover, the oncometabolites inhibit several α-ketoglutarate-dependent dioxygenases resulting in epigenetic changes such as DNA and histone hypermethylation as well as deficiencies in DNA repair. L-2HG, and D-2HG in some cases, inhibit degradation of hypoxia-inducible factor (HIF1α), a transcription factor that alters gene expression to adapt to hypoxic conditions, favoring tumorigenesis. Patients with the rare disease 2-hydroxyglutaric aciduria (2HGA) have exceedingly high levels of 2HG, which is neurotoxic, causing developmental delays and brain abnormalities. D-2HG also has specific effects on collagen production and NADPH pools. Recently, D-2HG has been targeted in new chemotherapies aimed at disrupting the gain-of-function IDH1 and IDH2 mutants, resulting in successful clinical trials for several cancers.

Herein we report the assessment of the effects of shockwave (SW) impacts on adult rat hippocampal progenitor cell (AHPC) neurospheres (NSs), which are used as in vitro brain models, for enhancing our understanding of the mechanisms of traumatic brain injury (TBI). The assessment has been achieved by using culture dishes and a new microchip. The microchip allows the chemicals released from the brain models cultured inside the cell culture chamber under SW impacts to diffuse to the nanosensors in adjacent sensor chambers through built-in diffusion barriers, which are used to prevent the cells from entering the sensor chambers, thereby mitigating the biofouling issues of the sensor surface. Experiments showed the negative impact of the SW on the viability, proliferation, and differentiation of the cells within the NSs. A qPCR gene expression analysis was performed and appeared to confirm some of the immunocytochemistry (ICC) results. Finally, we demonstrated that the microchip can be used to monitor lactate dehydrogenase (LDH) released from the AHPC-NSs subjected to SW impacts. As expected, LDH levels changed when AHPC-NSs were injured by SW impacts, verifying this chip can be used for assessing the degrees of injuries to AHPC-NSs by monitoring LDH levels. Taken together, these results suggest the feasibility of using the chip to better understand the interactions between SW impacts and in vitro brain models, paving the way for potentially establishing in vitro TBI models on a chip.

BACKGROUND: There is no evidence to determine the association between the lactate dehydrogenase to albumin ratio (LAR) and the development of sepsis-associated acute kidney injury (SAKI). We aimed to investigate the predictive impact of LAR for SAKI in patients with sepsis.
METHODS: A total of 4,087 patients with sepsis from the Medical Information Mart for Intensive Care IV (MIMIC IV) database were included. Logistic regression analysis was used to identify the association between LAR and the risk of developing SAKI, and the relationship was visualized using restricted cubic spline (RCS). The clinical predictive value of LAR was evaluated by ROC curve analysis. Subgroup analysis was used to search for interactive factors.
RESULTS: The LAR level was markedly increased in the SAKI group (p < 0.001). There was a positive linear association between LAR and the risk of developing SAKI (p for nonlinearity = 0.867). Logistic regression analysis showed an independent predictive value of LAR for developing SAKI. The LAR had moderate clinical value, with an AUC of 0.644. Chronic kidney disease (CKD) was identified as an independent interactive factor. The predictive value of LAR for the development of SAKI disappeared in those with a history of CKD but remained in those without CKD.
CONCLUSIONS: Elevated LAR 12 h before and after the diagnosis of sepsis is an independent risk factor for the development of SAKI in patients with sepsis. Chronic comorbidities, especially the history of CKD, should be taken into account when using LAR to predict the development of AKI in patients with sepsis.

OBJECTIVE: This investigation explores the clinical significance of integrating serum lactate dehydrogenase (LDH) with a multivariate model for assessing the short-term prognosis of primary nasopharyngeal carcinoma (NPC). Epstein-Barr virus (EBV) quantification is a crucial prognostic indicator in NPC cases, but not all patients with NPC test positive for EBV. Furthermore, widespread adoption of EBV-DNA quantification remains challenging due to its high cost. Consequently, it is imperative to incorporate additional convenient and cost-effective prognostic markers to comprehensively evaluate patient outcomes.
METHODS: This retrospective analysis included 203 newly diagnosed NPC cases treated at the Affiliated Qingyuan Hospital of Guangzhou Medical University between January 2018 and March 2022. The dataset included personal information and clinical data, and the treatment protocols followed the CSCO guidelines. Efficacy assessments were based on the RECIST 1.1 criteria and were conducted after induction chemotherapy and one week and three months after radiotherapy.
RESULTS: A noteworthy correlation emerged between baseline serum LDH levels and treatment efficacy at one week after radiotherapy (P = 0.03) and at three months after radiotherapy (P < 0.01). Additionally, a prognostic model that incorporates age (P = 0.010), LDH (P < 0.001), C-reactive protein (P = 0.010), and alkaline phosphatase (P = 0.005) demonstrated robust predictive accuracy and clinical applicability.
CONCLUSIONS: This investigation substantiates the significant correlation between baseline serum LDH levels and NPC outcomes. Furthermore, we introduce a refined prognostic model that holds promise for informing personalized treatment strategies, thereby contributing to the advancement of the diagnosis of NPC.

Plasmodium knowlesi is the only Plasmodium that causes zoonotic disease among the Plasmodium that cause infection in humans. It is fatal due to its short asexual growth cycle within 24 h. Lactate dehydrogenase (LDH), an enzyme that catalyzes the final step of glycolysis, is a biomarker for diagnosing infection by Plasmodium spp. parasite. Therefore, this study aimed to efficiently produce the soluble form of P. knowlesi LDH (PkLDH) using a bacterial expression system for studying malaria caused by P. knowlesi. Recombinant pET-21a(+)-PkLDH plasmid was constructed by inserting the PkLDH gene into a pET-21a(+) expression vector. Subsequently, the recombinant plasmid was inserted into the protein-expressing Escherichia coli Rosetta(DE3) strain, and the optimal conditions for overexpression of the PkLDH protein were established using this strain. We obtained a yield of 52.0 mg/L PkLDH from the Rosetta(DE3) strain and confirmed an activity of 483.9 U/mg through experiments. This methodology for high-efficiency PkLDH production can be utilized for the development of diagnostic methods and drug candidates for distinguishing malaria caused by P. knowlesi.

A 3-year-old male neutered domestic shorthair cat presented with lethargy, hyporexia, and pyrexia of unknown origin. Biochemical analysis using a Beckman Coulter AU480 demonstrated marked increases in creatine kinase and aspartate aminotransferase, indicative of severe muscle injury, with concurrent presumptive myoglobinuria on urinalysis. A marked, non-physiologic increase in measured bicarbonate and resultant negative anion gap was documented; however, calculated bicarbonate obtained via a point-of-care blood gas analyzer was within normal limits. Laboratory error due to interference by lactate dehydrogenase was suspected and supported by the results of subsequent biochemical testing. Artifactual increases in bicarbonate have been documented in cases of rhabdomyolysis in horses, cows, and a bird. However, to the best of the authors\' knowledge, this is the first report to demonstrate this spurious change in a cat.

Herein, we investigated the anti-amoebic activity of phosphonium-chloride-based deep eutectic solvents against pathogenic Acanthamoeba castellanii of the T4 genotype. Deep eutectic solvents are ionic fluids composed of two or three substances, capable of self-association to form a eutectic mixture with a melting point lower than each substance. In this study, three distinct hydrophobic deep eutectic solvents were formulated, employing trihexyltetradecylphosphonium chloride as the hydrogen bond acceptor and aspirin, dodecanoic acid, and 4-tert-butylbenzoic acid as the hydrogen bond donors. Subsequently, all three deep eutectic solvents, denoted as DES1, DES2, DES3 formulations, underwent investigations comprising amoebicidal, adhesion, excystation, cytotoxicity, and cytopathogenicity assays. The findings revealed that DES2 was the most potent anti-amoebic agent, with a 94% elimination rate against the amoebae within 24 h at 30 °C. Adhesion assays revealed that deep eutectic solvents hindered amoebae adhesion to human brain endothelial cells, with DES2 exhibiting 88% reduction of adhesion. Notably, DES3 exhibited remarkable anti-excystation properties, preventing 94% of cysts from reverting to trophozoites. In cytopathogenicity experiments, deep eutectic solvent formulations and dodecanoic acid alone reduced amoebae-induced human brain endothelial cell death, with DES2 showing the highest effects. Lactate dehydrogenase assays revealed the minimal cytotoxicity of the tested deep eutectic solvents, with the exception of trihexyltetradecylphosphonium chloride, which exhibited 35% endothelial cell damage. These findings underscore the potential of specific deep eutectic solvents in combating pathogenic Acanthamoeba, presenting promising avenues for further research and development against free-living amoebae.

BACKGROUND: We aimed to observe the dynamic changes in glucose metabolic reprogramming-related parameters and their ability to predict neurological prognosis and all-cause mortality in cardiac arrest patients after the restoration of spontaneous circulation (ROSC).
METHODS: Adult cardiac arrest patients after ROSC who were admitted to the emergency or cardiac intensive care unit of the First Affiliated Hospital of Dalian Medical University from August 1, 2017, to May 30, 2021, were enrolled. According to 28-day survival, the patients were divided into a non-survival group (n=82) and a survival group (n=38). Healthy adult volunteers (n=40) of similar ages and sexes were selected as controls. The serum levels of glucose metabolic reprogramming-related parameters (lactate dehydrogenase [LDH], lactate and pyruvate), neuron-specific enolase (NSE) and interleukin 6 (IL-6) were measured on days 1, 3, and 7 after ROSC. The Acute Physiology and Chronic Health Evaluation II (APACHE II) score and Sequential Organ Failure Assessment (SOFA) score were calculated. The Cerebral Performance Category (CPC) score was recorded on day 28 after ROSC.
RESULTS: Following ROSC, the serum LDH (607.0 U/L vs. 286.5 U/L), lactate (5.0 mmol/L vs. 2.0 mmol/L), pyruvate (178.0 μmol/L vs. 70.9 μmol/L), and lactate/pyruvate ratio (34.1 vs. 22.1) significantly increased and were higher in the non-survivors than in the survivors on admission (all P<0.05). Moreover, the serum LDH, pyruvate, IL-6, APACHE II score, and SOFA score on days 1, 3 and 7 after ROSC were significantly associated with 28-day poor neurological prognosis and 28-day all-cause mortality (all P<0.05). The serum LDH concentration on day 1 after ROSC had an area under the receiver operating characteristic curve (AUC) of 0.904 [95% confidence interval [95% CI]: 0.851-0.957]) with 96.8% specificity for predicting 28-day neurological prognosis and an AUC of 0.950 (95% CI: 0.911-0.989) with 94.7% specificity for predicting 28-day all-cause mortality, which was the highest among the glucose metabolic reprogramming-related parameters tested.
CONCLUSIONS: Serum parameters related to glucose metabolic reprogramming were significantly increased after ROSC. Increased serum LDH and pyruvate levels, and lactate/pyruvate ratio may be associated with 28-day poor neurological prognosis and all-cause mortality after ROSC, and the predictive efficacy of LDH during the first week was superior to others.