Affinity ultrafiltration and UPLC-HR-Orbitrap-MS based screening of thrombin-targeted small molecules with anticoagulation activity from Poecilobdella manillensis.

This study aims to screen potential anticoagulant components from leeches, a representative animal-sourced traditional Chinese medicine using thrombin (THR)-targeted ultrafiltration combined with ultrahigh performance liquid chromatography and high-resolution Orbitrap mass spectrometry (UPLC-HR-Orbitrap-MS). As a result, five small molecules in leech extract were discovered to interact with THR for the first time. Among them, two new compounds were isolated and their structures were identified by IR, HR-MS and NMR data. Furthermore, their THR inhibitory activity was confirmed with IC50 values of 4.74 and 8.31 µM, respectively. In addition, molecular docking analysis showed that the active (catalytic) site of THR might be the possible binding site of the two hits. Finally, reverse screening analysis indicated that LTA4-H, ACE and ALOX5AP were potential anticoagulant targets of the two new compounds. This study will broaden our understanding of the medicinal substance basis in leeches and further contribute to the discovery and development of clinical anticoagulant drugs from leeches.

Neutrophil-lymphocyte ratio as a prognostic factor for minute clear cell renal cell carcinoma diagnosed using multi-slice spiral CT.

ABSTRACT: Minute clear cell renal cell carcinoma (MccRCC) has a diameter of <1.5 cm and can be diagnosed using multi-slice spiral CT (MSCT). Recently, the role of the neutrophil-lymphocyte ratio (NLR) in the development of MccRCC has attracted attention. This study aimed to further explore the relationship between the NLR and MccRCC.This was a prospective study of 100 patients who were diagnosed with MccRCC using MSCT at Urumqi Friendship Hospital, China. The study investigated a series of pretreatment factors, including NLR and patients' general clinical data. Statistical methods employed included Pearson's chi-square test, Spearman-rho correlation test, Cox regression analysis, and receiver operator characteristic curve analysis.Based on Pearson's χ2, Spearman-rho test, and univariate/multivariate Cox regression analysis, the overall survival of patients with MccRCC was shown to be significantly related to NLR (P < .001). NLR (hazard ratio = 50.676, 95%CI, 17.543-146.390, P < .001) is a significant independent risk-factor for MccRCC. A receiver operator characteristic curve was plotted to examine specificity and sensitivity between NLR and MccRCC (area under curve = 0.958, P < .001).The level of the NLR plays a crucial role in the survival of patients with MccRCC, as diagnosed with MSCT. The higher the NLR, the worse the prognosis for patients with MccRCC.

A novel thrombin inhibitory peptide discovered from leech using affinity chromatography combined with ultra-high performance liquid chromatography-high resolution mass spectroscopy.

Thrombin (THR) inhibitors play an important role in the treatment of thrombotic diseases. This study established a THR-based bio-specific extraction coupled with affinity chromatography and ultra-high performance liquid chromatography-high resolution mass spectroscopy (UPLC-HR-MS) analysis method to screen and identify THR ligands in Leech. After evaluating the reliability of the screening method using positive control drug (hirudin), it was successfully used to screen the potential active constituents in leech. And a comprehensive analysis of the peptides in leech elution was performed by UPLC-HR-MS, a total of 34 peptides were identified. At the same time, anti-THR activity was explored and inferred by searching databases and published literature. As a result, six peptides were discovered to be potential active compounds in leech. Further, the six peptides were synthesized and in vitro enzymatic activity assay was performed. Finally, SYELPDGQVITIGNER was screened as an anti-THR peptide with an IC50 value of 255.75 µM and it was discovered for the first time from Whitmania pigra Whitman and Hirudo nipponica Whitman. The molecular docking study showed that THR inhibitory activity of the polypeptide was mainly attributed to the hydrogen bond interactions, van der Waals forces and electrostatic interactions interaction between polypeptide and THR. These results suggest that the polypeptide is a potential natural THR inhibitor that can be used as anticoagulant.