A novel "off-on" fluorescent probe for the detection of nickel ions and its clinical application.

Nickel serves as an essential micronutrient for the human body, playing a vital role in various enzymatic processes. However, excessive nickel entering the environment can cause pollution and pose serious risks to animals, plants, and human health. High concentrations of nickel ions in the human body increase the risk of various diseases, highlighting the need for accurate measurement of nickel ions levels. In this study, we designed a sequence-specific cleavage probe for nickel (II) ion called SSC-Ni. Similar to the TaqMan probe, SSC-Ni is an off-on fluorescent probe with an exceptionally low background fluorescence signal. It exhibits high detection specificity, making it highly selective for nickel ions, and the detection limit of the probe towards Ni2+ is as low as 82 nM. The SSC-Ni probe can be utilized for convenient and cost-effective high-throughput quantitative detection of nickel ions in serum. Its user-friendly operation and affordability make it a practical solution. By addressing the lack of simple and effective nickel ion detection methods, this probe has the potential to contribute significantly to environmental monitoring and the protection of human health.

Simultaneous detection of human norovirus GI, GII and SARS-CoV-2 by a quantitative one-step triplex RT-qPCR.

Background: There are many similarities in the clinical manifestations of human norovirus and SARS-CoV-2 infections, and nucleic acid detection is the gold standard for diagnosing both diseases. In order to expedite the identification of norovirus and SARS-CoV-2, a quantitative one-step triplex reverse transcription PCR (RT-qPCR) method was designed in this paper. Methods: A one-step triplex RT-qPCR assay was developed for simultaneous detection and differentiation of human norovirus GI (NoV-GI), GII (NoV-GII) and SARS-CoV-2 from fecal specimens. Results: The triplex RT-qPCR assay had high detection reproducibility (CV < 1%) and sensitivity. The lower limits of detection (LLOD95) of the triplex RT-qPCR assay for each target site were 128.5-172.8 copies/mL, and LLOD95 of the singleplex RT-qPCR assay were 110.3-142.0 copies/mL. Meanwhile, among the detection of clinical oropharyngeal swabs and fecal specimens, the results of the singleplex and triplex RT-qPCR assay showed high agreement. Conclusion: The triplex RT-qPCR assay for simultaneous detection of NoV-GI, NoV-GII and SARS-CoV-2 from fecal specimens has high clinical application value.

The retracted conformation of ubiquitin Ser65 phosphorylation inhibits the formation of K48-linked ubiquitin chains.

PINK1, as the first reported ubiquitin kinase, can phosphorylate ubiquitin (Ub) at Ser65 site, which regulates the structure and function of Ub monomer. However, the levels of PINK1 and phosphorylated Ub (pUb) are very low in normal cells. Here we show that when proteasome activity is inhibited, the levels of soluble PINK1 (sPINK1) and pUb will increase significantly. Further we show that ubiquitin phosphorylation can inhibit the formation of K48-linked ubiquitin chains in vivo and in vitro, and the retracted state of pUb plays a leading role in the inhibition process. Ubiquitination is a necessary process for substrates degradation. Thus, phosphorylation can regulate proteasomal degradation of substrates.

Role of Wnt/ß-catenin pathway agonist SKL2001 in Caerulein-induced acute pancreatitis.

The goal of this study was to clarify the protective role of the Wnt/ß-catenin pathway agonist SKL2001 in a rat model of Caerulein-induced acute pancreatitis. AR42J cells and rats were divided into 4 groups: control, Caerulein, SKL2001 + Caerulein, and SKL2001 + control. Cell apoptosis was examined using flow cytometry. Hematoxylin-eosin staining was performed to observe pathological changes in pancreatic and small intestinal tissues. Inflammatory cytokines were detected by enzyme-linked immunosorbent assay (ELISA), while genes related to the Wnt/ß-catenin pathway were quantified using quantitative real-time PCR. In vitro results showed that Caerulein promoted cell necrosis, inhibited the Wnt/ß-catenin pathway, and increased the level of inflammatory cytokines. However, SKL2001 reduced cell necrosis and inflammatory cytokines and activated the Wnt/ß-catenin pathway. Additionally, in vivo results demonstrated the accumulation of fluid (i.e., edema), hemorrhage, inflammation and necrosis of the pancreatic acini occurred 6 h after the final Caerulein induction, with the damage reaching a maximal level 12 h after the final Caerulein induction; meanwhile, the Wnt/ß-catenin pathway was evidently inhibited with an enhanced level of inflammatory cytokines. The aforementioned damage was further aggravated 12 h later. Nevertheless, the pancreatic and small intestinal tissue damages were alleviated in Caerulein-induced rats treated with SKL2001. In conclusion, activation of the Wnt/ß-catenin pathway could inhibit Caerulein-induced cell apoptosis and inflammatory cytokine release, thus improving pancreatic and intestinal damage in rats with acute pancreatitis.

TNFSF15 is likely a susceptibility gene for systemic lupus erythematosus.

We aim to explore the correlation of TNFSF15 genetic polymorphisms with susceptibility to systemic lupus erythematosus (SLE). This study enrolled SLE patients and healthy individuals to detect three single nucleotide polymorphisms (SNPs) of TNFSF15 (rs3810936, rs6478108 and rs4979462) through using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to analyze the possible association of these three SNPs with the risk of SLE and the mRNA level of TNFSF15 was quantified by real-time PCR. The rs3810936 T allele carrier greatly decreased risk of SLE (OR = 0.620, 95% CI = 0.454-0.849, P = 0.003), while the risk of SLE for rs4979462 T allele carrier was significantly increased (OR = 1.66, 95% CI = 1.243-2.218, P < 0.001). The mRNA level of TNFSF15 was obviously higher in SLE patients, and specifically, the patients who carried the CC genotype of TNFSF15 rs3810936 had a higher TNFSF15 mRNA, but the rs4979462 CC genotype carriers appeared to be associated with the decreased TNFSF15 mRNA (all P < 0.05). Besides, the genotypes of rs3810936 and rs4979462 of TNFSF15 were significantly associated with butterfly rash, arthritis, serositis, renal nephritis, hematological disorder, immunological disorder and positive antinuclear antibody (ANA) of SLE patients (all P < 0.05). CCT and CTT haplotypes were risk factors of SLE, but CCC and TTT were protective factors of SLE (all P < 0.05). Logistic regression analysis showed that rs3810936 and rs4979462 of TNFSF15, histories of chilblain and wet living environment were independently associated with the risk of SLE (all P < 0.05).The current results suggested that TNFSF15 (rs3810936 and rs4979462) SNPs may confer susceptibility to SLE risk, which were significantly associated with the clinical phenotypes of SLE.

Changes of serum osteocalcin, calcium, and potassium in a rat model of type 2 diabetes.

Changes in serum levels of calcium (Ca), phosphorus (P), Ca phosphate, alkaline phosphatase (AKP), and osteocalcin (BGP) were assessed in a model of type 2 diabetes in 8-weeks-old Sprague-Dawley rats. Throughout the study, the animals in Group A consumed high-carbohydrate, high-fat diet and were administered two intraperitoneal injections of streptozocin (STZ) at 4 (25 mg/kg) and 8 (40 mg/kg) weeks after diet initiation. Animals in Group B received similar diet but intraperitoneal injections with citrate buffer. The control group rats (Group C) were fed normal diet and received citrate buffer injections. The Ca levels in Group A were significantly decreased at 12 and 16 weeks, while P levels were significantly lower at 8, 12, and 16 weeks after the first STZ injection (p < 0.05 vs. Groups B and C). The Ca phosphate levels in Group A were significantly lower at 16 weeks (p < 0.05 vs. Groups B and C). There was a discrepancy in kinetics of AKP and BGP levels in Group A, such that the former showed a significant surge at 8 weeks (p < 0.05 vs. Groups B and C) followed by a decline at 16 weeks (p < 0.05 vs. Groups B and C), while the levels of the latter consistently decreased and became significantly decreased at 12 and 16 weeks (p < 0.05 vs. Groups B and C). In conclusion, these findings may lead to better understanding of the pathogenesis of osteoporosis in diabetic rats.