Elevating sensing capability via dual-atom catalysts boosted luminol cathodic electrochemiluminescence.

BACKGROUND: The advancement of highly sensitive electrochemiluminescence (ECL) biosensors has garnered escalating interest over time. Owing to the distinctive physicochemical attributes, the signal amplification strategy facilitated by functional nanomaterials has achieved notable milestones. Single-atom catalysts (SACs), featuring atomically dispersed metal active sites, have garnered significant attention. SACs offer unprecedented control over active sites and surface structures at the atomic level. However, to fully harness their potential, ongoing efforts focus on strategies to enhance the catalytic performance of SACs, profoundly influencing both the sensitivity and selectivity of SACs-based sensing platforms. RESULTS: In this study, we focused on the synthesis and application of Fe-Co-PNC dual-atom catalysts (DACs) with the incorporation of phosphorus, aiming to enhance catalytic efficiency, particularly in the context of the oxygen reduction reaction (ORR) correlated cathodic luminol ECL. The synergistic effects arising from the combination of Fe and Co in DACs were explored by ECL emission. Comparative studies with Fe-PNC SACs highlighted the superior catalytic performance of Fe-Co-PNC DACs. The ECL sensing platform exhibited excellent sensitivity, which provided a fast detection of Trolox with a wide linear range (0.1 µM-1.0 mM) and a low detection limit (LOD) of 0.03 µM. The platform demonstrated remarkable reproducibility and long-term stability, showcasing its potential for practical biosensing applications. SIGNIFICANCE: This study introduced the novel concept of Fe-Co-PNC DACs. The demonstrated synergistic effects and enhanced catalytic efficiency of DACs offer new avenues for the rational design of advanced catalysts. The successful application in the sensitive detection of Trolox emphasizes their potential significance in biosensing. It not only expands our understanding of SACs but also opens doors for the development of efficient and stable catalysts with broader applications.

Analysis of several loci from genome-wide association studies in Parkinson's disease in mainland China.

Large-scale meta-analyses of genome-wide association studies in Parkinson's disease (PD) have identified a number of susceptibility loci in sporadic PD. Since the characteristics of those loci in a Han Chinese population from mainland China were unknown, we performed a case-control replication study in this population and evaluated several single nucleotide polymorphisms (SNPs) identified in a recent GWAS-meta-analysis. In total, 933 subjects comprised of 460 PD patients and 473 controls were genotyped. We found strong evidence of an association for rs708723 in RAB7L1 in the total sample (genotype p=0.01, allele p=0.01, OR=0.78, 95% CI=0.65-0.94). With rs156429 in GPNMB, there was a significant difference in genotype and allele distribution between male PD patients and the control subgroup (genotype p=0.01, allele p=0.01, OR=0.67, 95% CI=0.49-0.92). However, we did not observe any significant difference in genotype or allele distribution between PD and control for rs34016896 in NMD3 and rs6812193 in STBD1.

Irinotecan-involved regimens for advanced gastric cancer: a pooled-analysis of clinical trials.

AIM: To assess the efficiency and toxicities of irinotecan (CPT-11)-involved regimens in patients with advanced gastric cancer. METHODS: Randomized phases II and III clinical trials on chemotherapy for advanced gastric cancer were searched from MEDLINE, EMbase, Cochrane Controlled Trials Register, and EBSCO. Relevant abstracts were manually searched. A total of 657 patients were analyzed for their overall response rate (ORR), time to treatment failure (TTF), overall survival (OS) rate, and toxicities. Overall survival rate, reported as hazard ratio (HR) with 95% CI, was used as the primary outcome measure. RESULTS: Four randomized controlled trials on chemotherapy for advanced gastric cancer were detected. The CPT-11-containing combination chemotherapy was not significantly advantageous over the non CPT-11-containing combination chemotherapy for OS rate (HR = 1.12, 95% CI: 0.92-1.36, P = 0.266) and ORR [risk ratio (RR) = 1.23, 95% CI: 0.71-2.14, P = 0.458]. However, the CPT-11-containing combination chemotherapy was significantly advantageous over the non CPT-11-containing combination chemotherapy for TTF (HR = 1.35, 95% CI: 1.12-1.64, P = 0.002). Grade 3/4 haematological toxicity (thrombocytopenia: RR = 0.20, 95% CI: 0.09-0.48; P < 0.001) and gastrointestinal toxicity (diarrhea: RR = 4.09, 95% CI: 2.42-6.93, P < 0.001) were lower in patients with advanced gastric cancer after CPT-11-containing combination chemotherapy than after non CPT-11 -containing combination chemotherapy. CONCLUSION: CPT-11-containing combination chemotherapy is advantageous over non CPT-11 -containing combination chemotherapy for TTF with no significant toxicity. CPT-11-containing combination chemotherapy can be used in treatment of advanced gastric cancer.

Effect of inhibiting melatonin biosynthesis on spatial memory retention and tau phosphorylation in rat.

We have found recently that melatonin protects SH-SY5Y neuroblastoma cells from calyculin A-induced neurofilament impairment and neurotoxicity. In the present study, we further investigated the in vivo effect of inhibiting melatonin biosynthesis on spatial memory retention and tau phosphorylation in rats and the potential underlying mechanisms by using haloperidol, a specific inhibitor of 5-hydroxyindole-O-methyltransferase, and a key enzyme in melatonin biosynthesis. We have found that injection of haloperidol into the lateral ventricle and into peritoneal cavity compromises spatial memory retention of rats and induces hyperphosphorylation of microtubule-associated protein tau at tau-1 (Ser199/Ser202) and PHF-1 (Ser396/Ser404) epitopes. At mean time, the activity of protein phosphatase-2A (PP-2A), a deficit phosphatase in the Alzheimer's disease brain and superoxide dismutase decreases with an elevated level of malondialdehyde. Supplementation with melatonin by prior injection for 1 wk and reinforcement during the haloperidol administration significantly improves memory retention deficits, arrests tau hyperphosphorylation and oxidative stress, and restores PP-2A activity. These results strongly support the involvement of decreased melatonin in Alzheimer-like spatial memory impairment and tau hyperphosphorylation, and PP-2A may play a role in mediating aberrant melatonin-induced lesions.

Melatonin attenuates isoproterenol-induced protein kinase A overactivation and tau hyperphosphorylation in rat brain.

Hyperphosphorylation of microtubule-associated protein tau at specific sites is a recognized pathological process in Alzheimer's disease (AD), and protein kinase A (PKA) is a crucial kinase in AD-like tau hyperphosphorylation. In the present study, isoproterenol (ISO) was injected bilaterally into hippocampus of rat brain; ISO is a specific PKA activator and it induces tau hyperphosphorylation. With this system, melatonin (MT) was shown to protect against ISO-induced tau hyperphosphorylation. We found that hippocampal injection of ISO (0.02 microm) induced PKA overactivation and tau hyperphosphorylation at both paired helical filament (PHF)-1 and tau-1 sites. ISO injection also resulted in activation of superoxide dismutase (SOD) and elevation of malondialdehyde (MDA), parameters suggesting elevated oxidative stress. Preinfusion of MT intraperitoneally partially reversed ISO-induced tau hyperphosphorylation at the PHF-1 epitope (1 and 10 mg/kg continuously for 4 wk or 10 mg/kg for 1, 2 or 3 wk) and tau-1 epitope (10 mg/kg for 2 wk). Furthermore, MT (10 mg/kg for 2 wk) obviously antagonized ISO-induced PKA overactivation, as well as enhanced SOD activity and decreased the level of MDA. It is suggested from these data that ISO may induce abnormal hyperphosphorylation of tau through not only the activation of PKA but also because of the fact that it increases oxidative stress; MT may protect against ISO-induced tau hyperphosphorylation through suppression of both PKA overactivation and oxidative stress.