A Multimodal Meta-Analysis of Structural and Functional Alterations in the Brain of Knee Osteoarthritis Systematic Review.

BACKGROUND: Abnormalities of structural and functional brain regions might influence the persistence of knee pain, the progression, and the response to treatments in knee osteoarthritis (KOA). These complex alterations present a challenge to the understanding of its mechanism. OBJECTIVES: To meta-analyze the concurrence across structural and functional magnetic resonance imaging studies. STUDY DESIGN: Systematic review and meta-analysis. SETTING: This meta-analysis examined all voxel-based morphometric (VBM) and amplitude of low-frequency fluctuation (ALFF) studies involving the whole-brain alterations of KOA. METHODS: VBM and ALFF studies published up to May 7, 2023, were searched in the Web of Science, PubMed, EMBASE, Cochrane Library (CENTRAL), China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database, Chongqing VIP, Wanfang Database. Two independent researchers carried out study screening, quality assessment, clinical data extraction, and neuroimaging data extraction. The whole-brain voxel-based gray matter (GM) and brain activity data of KOA were collected from eligible studies and meta-analyzed using the anisotropic effect size-signed differential mapping (AES-SDM). RESULTS: Fourteen studies were included in this study. In VBM meta-analyses, a total of 481 patients were enrolled in this study (252 KOA and 229 healthy patients). In the ALFF meta-analysis, a total of 518 patients were enrolled in this study (265 KOA and 253 healthy patients). According to the meta-analysis, KOA had increased GM volume in the right inferior frontal gyrus and decreased GM volume in the bilateral superior frontal gyrus, as well as increased brain activity in the left inferior frontal gyrus and inferior temporal gyrus, and decreased brain activity in the left middle occipital gyrus, right supramarginal gyrus, right superior frontal gyrus, and right superior parietal gyrus compared with healthy patients. LIMITATIONS: Most of the ALFF studies included in this meta-analysis were conducted in China. Our findings are exclusively addressed by the VBM and ALFF studies. The meta-regression between the duration of KOA, pain intensity and abnormal gray matter, and functional activity of brain regions in patients with KOA were unable to be analyzed. CONCLUSION: The results of this meta-analysis indicate that patients with KOA present significant abnormalities in GM volume and functional activity. These findings contribute to a better understanding of the structural and functional abnormalities seen in patients with KOA.

Occurrence and prevention of incisional hernia following laparoscopic colorectal surgery.

Among minimally invasive surgical procedures, colorectal surgery is associated with a notably higher incidence of incisional hernia (IH), ranging from 1.7% to 24.3%. This complication poses a significant burden on the healthcare system annually, necessitating urgent attention from surgeons. In a study published in the World Journal of Gastrointestinal Surgery, Fan et al compared the incidence of IH among 1614 patients who underwent laparoscopic colorectal surgery with different extraction site locations and evaluated the risk factors associated with its occurrence. This editorial analyzes the current risk factors for IH after laparoscopic colorectal surgery, emphasizing the impact of obesity, surgical site infection, and the choice of incision location on its development. Furthermore, we summarize the currently available preventive measures for IH. Given the low surgical repair rate and high recurrence rate associated with IH, prevention deserves greater research and attention compared to treatment.

Efficacy of first-line chemotherapy based on primary site of tumor versus etoposide-platinum in advanced gastroenteropancreatic neuroendocrine carcinoma.

Background: Gastroenteropancreatic neuroendocrine carcinomas (GEP-NECs) constitute a rare and aggressive group of malignancies usually with widespread disease. There are limited studies on GEP-NECs, and therefore, we aim to acquire more information on the clinical features, treatment regimens, and prognosis. Methods: Data from advanced GEP-NECs patients who had not previously received systemic treatment for advanced disease at The First Affiliated Hospital of Nanjing Medical University from 2010 to 2022 were retrospectively collected. Relationships between clinical-pathological features, treatment regimens, and prognosis were investigated using Kaplan-Meier curves and cox regression models. Results: A total of fifty-four patients were enrolled in the study. The median age was 65.5 years and 79.6% were male. At diagnosis, 51.9% and 3.7% of patients developed liver and brain metastasis respectively. Sixteen (29.6%) patients received chemotherapy according to primary site of tumor (PST), while thirty-eight (70.4%) were treated with etoposide-platinum (EP) regimen, which based on the first-line treatment of advanced small cell lung cancer (SCLC). No significant differences on progression-free survival (PFS) and response rate were observed between these two groups. Univariate survival analysis showed that liver metastasis, elevated baseline serum carcinoembryonic antigen, elevated baseline serum neuron-specific enolase, elevated baseline serum lactate dehydrogenase, and elevated baseline serum neutrophil-to-lymphocyte ratio (NLR) were associated with shorter PFS. After multivariate analysis, elevated NLR was the only factor that remained significantly associated with shorter PFS (P=0.01). Conclusions: GEP-NECs are aggressive neoplasms, of which elevated NLR is proven to be an independent negative predictor. Treatment regimens based on PST are not inferior to regiments based on SCLC (EP) for GEP-NECs patients. Large-scale, prospective randomized controlled trials are required to establish the standard of care.

TCGA Database-Based Screening of Tumor Microenvironment Immunomodulators Related to Bladder Cancer Prognosis.

OBJECTIVE: Bladder cancer (BC), as the most common malignant tumor of the urinary tract, has a complex biological behavior. Currently, there are still some limitations in the diagnosis and treatment of BC. Despite the great progress made in immunotherapy, there is still a lack of key genes for the diagnosis of BC. Therefore, it is particularly important to explore the differentially expressed genes (DEGs) and their effectiveness on prognosis of BC with different tumor microenvironment scores. METHODS: The gene expression dataset of BC was downloaded from the Cancer Genome Atlas (TCGA) database. The correlation between clinicopathological characteristics of patients and scores of immune and stromal components was analyzed. Patients were divided into high and low score groups according to their tumor microenvironment score (Immune score, Stromal score, ESTIMATE score). DEGs between high and low score groups were identified using R software and then subjected to enrichment analyses to assess their potential biological functions and signaling pathways. The protein-protein interaction (PPI) network was constructed using the STRING database to further identify hub genes. The expression levels of hub genes in BC were verified by TCGA database. Subsequently, the hub genes were evaluated for overall survival (OS), disease-free survival (DFS), progression-free survival (PFS), and disease-specific survival (DSS), and corresponding forest plots were created. RESULTS: A total of 2346 DEGs were obtained, including 1120 up-regulated genes and 1226 down-regulated genes. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses found DEGs were mainly enriched in cell migration and immune-related pathways. Meanwhile, The PPI network finally yielded top 10 hub genes with predictive value, which included actin beta (ACTB), interleukin 6 (IL-6), Jun proto-oncogene (JUN), CD4 molecule (CD4), heat shock protein 90 alpha family class A member 1 (HSP90AA1), protein tyrosine phosphatase receptor type C (PTPRC), tumor protein p53 (TP53), SRC proto-oncogene (SRC), fibronectin 1 (FN1), and tumor necrosis factor (TNF). Among them, CD4, PTPRC, and SRC were potential protective factors for BC. CONCLUSION: The top 10 hub genes (ACTB, IL-6, JUN, CD4, HSP90AA1, PTPRC, TP53, SRC, FN1, TNF) obtained based on tumor microenvironment scores all had potential predictive value. Elevated expression of protective factors (CD4, PTPRC, and SRC) indicates better survival outcome of BC subjects. Further exploration of the molecular developmental mechanisms of these hub genes will help to develop novel personalized therapies and improve BC prognosis.

Mechanical factors influence ß-catenin localization and barrier properties.

Mechanical forces are of major importance in regulating vascular homeostasis by influencing endothelial cell behavior and functions. Adherens junctions are critical sites for mechanotransduction in endothelial cells. ß-catenin, a component of adherens junctions and the canonical Wnt signaling pathway, plays a role in mechanoactivation. Evidence suggests that ß-catenin is involved in flow sensing and responds to tensional forces, impacting junction dynamics. The mechanoregulation of ß-catenin signaling is context-dependent, influenced by the type and duration of mechanical loads. In endothelial cells, ß-catenin's nuclear translocation and signaling are influenced by shear stress and strain, affecting endothelial permeability. The study investigates how shear stress, strain, and surface topography impact adherens junction dynamics, regulate ß-catenin localization, and influence endothelial barrier properties. Insight box Mechanical loads are potent regulators of endothelial functions through not completely elucidated mechanisms. Surface topography, wall shear stress and cyclic wall deformation contribute overlapping mechanical stimuli to which endothelial monolayer respond to adapt and maintain barrier functions. The use of custom developed flow chamber and bioreactor allows quantifying the response of mature human endothelial to well-defined wall shear stress and gradients of strain. Here, the mechanoregulation of ß-catenin by substrate topography, wall shear stress, and cyclic stretch is analyzed and linked to the monolayer control of endothelial permeability.

Recent advances in the synthesis of trifluoromethyl-containing heterocyclic compounds via trifluoromethyl building blocks.

Trifluoromethylated heterocyclic compounds have played an increasingly significant role in pharmaceuticals, agrochemicals, and materials. This is because the introduction of trifluoromethyl could enhance the lipophilicity, metabolic stability, and pharmacokinetic properties of heterocyclic drug molecules. Therefore, the synthesis of trifluoromethylated heterocyclics has become a major subject of research. The construction of trifluoromethylated heterocyclics via the annulation of trifluoromethyl building blocks with suitable partners has been proved to be a powerful strategy. In this review, we systematically summarize and discuss recent advances in the preparation of trifluoromethyl-containing heterocyclics via trifluoromethyl building block strategies over the period from 2019 to the present.

Accelerated phase development in a late-onset adolescent Chediak-Higashi syndrome patient caused by compound novel LYST mutations in the setting of SARS-CoV-2 infection.

Chediak-Higashi syndrome (CHS) is a rare autosomal recessive genetic disorder characterized by severe immunodeficiency, albinism and coagulation deficiency. Mostly diagnosed in early childhood, this devastating condition is associated with lysosomal abnormalities attributed to the absence or impaired function of lysosomal trafficking regulator caused by mutations in the CHS1/LYST gene. In current study, we report a case of late-onset CHS caused by two novel compound heterozygous CHS1/LYST mutations: c.8407C > T, leading to early termination of translation at residue Gln2803 (p. Gln2803Ter), and a small deletion c. 4020_4031del, resulting in an in-frame deletion of three amino acid residues (p. Asp1343_Val1346del). Both variants retain a large part of the CHS/LYST protein, particularly p. Asp1343_Val1346del, which preserves critical functional BEACH and WD40 domains in the C terminal, potentially maintaining residual activity and alleviating patient symptoms. The timeline of SARS-CoV-2 infection and rapid symptom progression suggests that the viral infection may have trigger the accelerated phase development leading to a poor prognosis.

Selective CO2 Photoreduction into CH4 Triggered by the Synergy between Oxygen Vacancy and Ru Substitution under Near-Infrared Light Irradiation.

Near-infrared (NIR) light powdered CO2 photoreduction reaction is generally restricted to the separation efficiency of photogenerated carriers and the supply of active hydrogen (*H). Herein, the study reports a retrofitting hydrogenated MoO3-x (H-MoO3-x) nanosheet photocatalysts with Ru single atom substitution (Ru@H-MoO3-x) fabricated by one-step solvothermal method. Experiments together with theoretical calculations demonstrate that the synergistic effect of Ru substitution and oxygen vacancy can not only inhibit the recombination of photogenerated carriers, but also facilitate the CO2 adsorption/activation as well as the supply of *H. Compared with H-MoO3-x, the Ru@H-MoO3-x exhibit more favorable formation of *CHO in the process of *CO conversion due to the fast *H generation on electron-rich Ru sites and transfer to *CO intermediates, leading to the preferential photoreduction of CO2 to CH4 with high selectivity. The optimized Ru@H-MoO3-x exhibits a superior CO2 photoreduction activity with CH4 evolution rate of 111.6 and 39.0 µmol gcatalyst -1 under full spectrum and NIR light irradiation, respectively, which is 8.8 and 15.0 times much higher than that of H-MoO3-x. This work provides an in-depth understanding at the atomic level on the design of NIR responsive photocatalyst for achieving the goal of carbon neutrality.

Clinical Implications of Acute Stent Mal-Apposition in the Left Main Coronary Artery.

Background: Intravascular ultrasound (IVUS) has been utilized to determine acute stent mal-apposition (ASM) after percutaneous coronary intervention (PCI) in the left main coronary artery (LMCA). However, the clinical consequences of this finding remain uncertain. This research aimed to evaluate the clinical implications of ASM in the LMCA using IVUS. Methods: In this study, 408 patients who underwent successful drug-eluting stent (DES) implantation in the LMCA were evaluated. We analyzed the prevalence and characteristics of ASM and its correlation with clinical outcomes. ASM is characterized by stent struts that are not in immediate proximity to the intimal surface of the vessel wall after initial stent deployment. Results: The observed incidence of LMCA-ASM post-successful PCI was 26.2%, both per patient and per lesion. Lesions with LMCA-ASM had a longer stent diameter, larger stent areas, and larger lumen areas compared to those without LMCA-ASM (4.0 ± 0.5 vs. 3.7 ± 0.4 mm, p < 0.001; 9.8 ± 2.0 vs. 9.0 ± 1.6 mm 2 , p < 0.001; 12.3 ± 1.9 vs. 10.1 ± 2.1 mm 2 , p < 0.001, respectively). The mean external elastic membrane (EEM) area (odds ratio (OR): 1.418 [95% confidence interval (CI): 1.295-1.556]; p < 0.001) emerged as an independent predictor of LMCA-ASM. During the observation period, LMCA-ASM did not display any association with device-oriented clinical endpoints (DoCE), which included cardiac death, target vessel-induced myocardial infarction (MI), stent thrombosis, and target lesion revascularization (TLR). Moreover, the DoCE incidence exhibited no significant disparity between patients with or without ASM (13.1 vs. 6.0%, p = 0.103). Conclusions: While LMCA-ASM was a not uncommon finding post-PCI, it did not correlate with adverse cardiac events in the present study.

Calcified Nodules in Non-Culprit Lesions with Acute Coronary Syndrome Patients.

Background: Calcified nodules (CN) have been linked to unfavorable clinical outcomes. However, there is a lack of systematic studies on non-culprit lesions with CN in patients with acute coronary syndromes (ACS). This study aims to investigate the frequency, distribution, predictors, and outcomes of CN in non-culprit lesions among ACS patients. Methods: We included 376 ACS patients who received successful stent placement in their culprit lesions. Intravascular ultrasound (IVUS) was performed to evaluate non-culprit lesions in left main arteries and all three coronary arteries (CA). CN was defined as accumulations of small nodular calcium deposits exhibiting a convex shape protruding into the lumen. Results: CNs was identified in 16.9% (121 of 712) per artery and 26.9% (101 of 376) per patient. They were predominantly located at the mid portion of the right coronary artery (26.3%) and the bifurcation site (59.9%). Patients with CN were older (63.57 ± 8.43 vs. 57.98 ± 7.15, p < 0.001) and had a higher prevalence of diabetes mellitus (55.4% vs. 42.2%, p = 0.022). However, there were no significant differences in baseline characteristics observed after propensity score matching (PSM). Multivariate analysis revealed that CN were independently associated with major adverse cardiovascular events (MACE) both before and after PSM (hazard ratio (HR): 0.341, 95% confidence interval (95% CI): 0.140-0.829, p = 0.018; HR: 0.275, 95% CI: 0.108-0.703, p = 0.007, respectively). During the observational period of 19.35 ± 10.59 months, the occurrence of MACE was significantly lower in patients with CN before and after PSM (5.9% vs. 16.7%, p = 0.046; 4.0% vs. 18.1%, p = 0.011; respectively). Conclusions: CN in non-culprit lesions with ACS patients was prevalent and caused fewer adverse clinical outcomes.

Volumetric Stent Expansion Index to Assess Tapering Lesions Using Intravascular Ultrasound and Its Clinical Outcomes.

Background: This study aimed to assess the clinical significance of generating a volumetric stent expansion index for tapering lesions through intravascular ultrasound (IVUS). Previous IVUS studies have used minimal stent area (MSA) to predict adverse outcomes. Methods: A total of 251 tapering lesions were treated in this study via IVUS guidance in 232 patients. Eight stent expansion indices were evaluated to determine the association of these indices with device-oriented clinical endpoints (DoCEs) after two-year follow-ups. These were the ILUMIEN III and IV standards, the ULTIMATE (Intravascular Ultrasound Guided Drug Eluting Stents Implantation in "All-Comers" Coronary Lesions) standard, the IVUS-XPL (Impact of Intravascular Ultrasound Guidance on the Outcomes of Xience Prime Stents in Long Lesions) standard, the minimal volumetric expansion index (MVEI) using the Huo-Kassab or linear model, the MSA/vessel area at the MSA cross-section, the traditional stent expansion (MSA/mean proximal and distal reference lumen cross-sectional area), and MSA. Results: The MVEI was the only stent expansion index that correlated significantly with the two-year DoCEs (hazard ratio [HR], 1.91; 95% confidence interval [CI]: 1.16-3.96; p = 0.028). In the ROC analysis, the area under the curve for the MVEI was 0.71 (p = 0.002), with an optimal cut-off value of 62.2 for predicting the DoCEs. Conclusions: This is the first study to use IVUS for tapering lesions and demonstrate that the MVEI is an independent predictor of two-year DoCEs.

Characterization of maltose-binding protein-fused heparinases with enhanced thermostability by application of rigid and flexible linkers.

Heparinases, including heparinases I-III (HepI, HepII, and HepIII, respectively), are important tools for producing low-molecular-weight heparin, an improved anticoagulant. The poor thermostability of heparinases significantly hinders their industrial and laboratory applications. To improve the thermostability of heparinases, we applied a rigid linker (EAAAK)5 (R) and a flexible linker (GGGGS)5 (F) to fuse maltose-binding protein (MBP) and HepI, HepII, and HepIII from Pedobacter heparinus, replacing the original linker from the plasmid pMAL-c2X. Compared with their parental fusion protein, MBP-fused HepIs, HepIIs, and HepIIIs with linkers (EAAAK)5 or (GGGGS)5 all displayed enhanced thermostability (half-lives at 30°C: 242%-464%). MBP-fused HepIs and HepIIs exhibited higher specific activity (127%-324%), whereas MBP-fused HepIIIs displayed activity similar to that of their parental fusion protein. Kinetics analysis revealed that MBP-fused HepIIs showed a significantly decreased affinity toward heparin with increased Km values (397%-480%) after the linker replacement, whereas the substrate affinity did not change significantly for MBP-fused HepIs and HepIIIs. Furthermore, it preliminarily appeared that the depolymerization mechanism of these fusion proteins may not change after linker replacement. These findings suggest the superior enzymatic properties of MBP-fused heparinases with suitable linker designs and their potential for the bioproduction of low-molecular-weight heparin.

Solvent-Controlled Enantiodivergent Construction of P(V)-Stereogenic Molecules via Palladium-Catalyzed Annulation of Prochiral N-Aryl Phosphonamides with Aromatic Iodides.

In this work, we describe an efficient and modular method for enantiodivergent accessing P(V)-stereogenic molecules by utilizing the catalytic atroposelective Catellani-type C-H arylation/desymmetric intramolecular N-arylation cascade reaction. The enantioselectivity of this protocol was proved to be tuned by the polarity of the solvent, thus providing a wide range of both chiral P(V)-stereogenic enantiomers in moderate to good yields with good to excellent enantiomeric excesses. Noteworthy is that the strategy developed herein represents an unprecedented example of solvent-dictated inversion of the enantioselectivity of P(V)-stereogenic compounds.

Rich-club organization of whole-brain spatio-temporal multilayer functional connectivity networks.

Objective: In this work, we propose a novel method for constructing whole-brain spatio-temporal multilayer functional connectivity networks (FCNs) and four innovative rich-club metrics. Methods: Spatio-temporal multilayer FCNs achieve a high-order representation of the spatio-temporal dynamic characteristics of brain networks by combining the sliding time window method with graph theory and hypergraph theory. The four proposed rich-club scales are based on the dynamic changes in rich-club node identity, providing a parameterized description of the topological dynamic characteristics of brain networks from both temporal and spatial perspectives. The proposed method was validated in three independent differential analysis experiments: male-female gender difference analysis, analysis of abnormality in patients with autism spectrum disorders (ASD), and individual difference analysis. Results: The proposed method yielded results consistent with previous relevant studies and revealed some innovative findings. For instance, the dynamic topological characteristics of specific white matter regions effectively reflected individual differences. The increased abnormality in internal functional connectivity within the basal ganglia may be a contributing factor to the occurrence of repetitive or restrictive behaviors in ASD patients. Conclusion: The proposed methodology provides an efficacious approach for constructing whole-brain spatio-temporal multilayer FCNs and conducting analysis of their dynamic topological structures. The dynamic topological characteristics of spatio-temporal multilayer FCNs may offer new insights into physiological variations and pathological abnormalities in neuroscience.

Hybrid 3C-silicon carbide-lithium niobate integrated photonic platform.

In this paper, we demonstrate a novel hybrid 3C-silicon carbide-lithium niobate (3C-SiC-LN) platform for passive and active integrated nanophotonic devices enabled through wafer bonding. These devices are fabricated by etching the SiC layer, with the hybrid optical mode power distributed between SiC and LN layers through a taper design. We present a racetrack resonator-based electro-optic (EO) phase shifter where the resonator is fabricated in SiC while using LN for EO-effect (r33≈ 27 pm/V). The proposed phase shifter demonstrates efficient resonance wavelength tuning with low voltage-length product (Vπ.Lπ ≈ 2.18 V cm) using the EO effect of LN. This hybrid SiC-LN platform would enable high-speed, low-power, and miniaturized photonic devices (e.g., modulators, switches, filters) operable over a broad range of wavelengths (visible to infrared) with applications in both classical and quantum nanophotonics.

ADGRL1 variants: From developmental and epileptic encephalopathy to genetic epilepsy with febrile seizures plus.

AIM: To expand the phenotypic spectrum of ADGRL1 and explore the correlation between epilepsy and the ADGRL1 genotype. METHOD: We performed whole-exome sequencing in a cohort of 115 families (including 195 males and 150 females) with familial febrile seizure or epilepsy with unexplained aetiology. The damaging effects of variants was predicted using protein modelling and multiple in silico tools. All reported patients with ADGRL1 pathogenic variants were analysed. RESULTS: One new ADGRL1 variant (p.Pro753Leu) was identified in one family with genetic epilepsy with febrile seizures. Further analysis of 12 ADGRL1 variants in 16 patients revealed that six patients had epilepsy. Epilepsy types ranged from early-onset epileptic encephalopathy to genetic epilepsy with febrile seizures plus (GEFS+). All four variants associated with epilepsy were located in the non-helix or sheet region of ADGRL1. Three of the four epilepsy-associated variants were missense variants. Thus, all three variants located in the G-protein-coupled receptor autoproteolytic-inducing domain exhibited epilepsy. INTERPRETATION: We found one new missense variant of ADGRL1 in one family with GEFS+. ADGRL1 may be a potential candidate or susceptibility gene for epilepsy. ADGRL1-associated epilepsy ranged from benign GEFS+ to severe epileptic encephalopathy; the genotypes and variant locations may help explain the phenotypic heterogeneity of patients with the ADGRL1 variant.

High-accuracy fiber Bragg grating inclinometer.

Inclination monitoring plays a significant role in research on deformation monitoring of slopes, inclination monitoring of bridges, earthquake monitoring, and other areas of monitoring. Existing electromagnetic signal-based inclinometers face practical issues such as difficulty adapting to harsh environments, poor large-scale networking capabilities, and unstable signal transmission. Hence, what we believe to be a novel inclinometer based on fiber sensing principles is proposed. The sensor employs suspension sensing based on the plumb principle, using bearings to overcome mechanical friction caused by rigid fixation between the mass block and the cantilever, thereby improving sensitivity and accuracy of the sensor. Key structural parameters of the sensor were optimized and simulated, followed by fabrication of the sensor and performance test on an inclination test platform. Experimental results indicate that, within a measurement range of ±9∘, the sensor exhibited a sensitivity of 305.2 pm/°, a resolution of approximately 3.3×10-4 ∘, an accuracy of 2%, a repeatability error of 1.9%, and favorable creep resistance stability for long-term measurement, thus addressing the requirements for slope deformation monitoring.

Heterozygous Prothrombin Mutation-Associated Thrombophilia.

BACKGROUND: Venous thromboembolism (VTE) is predisposed by thrombotic mutations in patients with hereditary thrombophilia. Although prothrombin deficiencies caused by homozygous or compound heterozygous mutations are associated with bleeding diathesis, rare cases have shown a correlation between heterozygous prothrombin mutations and thrombosis. MATERIALS AND METHODS: We surveyed genetic variants involved in thrombosis and hemostasis in 347 patients with unprovoked VTE or having a positive family history of thrombosis. For patients identified with heterozygous prothrombin mutations, we conducted family investigations and performed a thrombin generation test (TGT) to elucidate the thrombotic risk. Novel mutants were expressed and subjected to functional assays to clarify the underlying thrombotic mechanisms. RESULTS: Heterozygous prothrombin mutations were identified in 3.5% of patients (12/347), including three novel mutations Phe382Ser, Phe382Leu, and Asp597Tyr found in one patient each, as well as previously reported Arg541Trp mutation in four patients and Arg596Gln mutation in five patients. A total of 42 mutation carriers were identified within the 12 pedigrees, among whom 64.3% (27/42) had experienced thrombotic events. TGT results demonstrated hypercoagulability for carriers of the five mutations, with Arg596Gln showing the highest thrombin generation potential followed by Arg541Trp. The Phe382-associated mutations severely impaired thrombomodulin-binding ability of thrombin, resulting in obviously reduced protein C (PC) activation. The Asp597Tyr mutation exhibited a mild reduction in both inactivation by antithrombin and PC activation reactions. CONCLUSION: The presence of heterozygous prothrombin mutations represents a potential genetic predisposition for VTE. All thrombosis-associated mutations potentiate coagulation activity by either conferring antithrombin resistance and/or impairing PC pathway activity.

A novel method for high-sensitivity detection of SARS-CoV-2 using dual double-quenched fluorescence probes.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected many people around the world; fast and accurate detection of the virus can help control the spread of the virus. Reverse transcription-polymerase chain reaction (RT-PCR) is the gold standard method for SARS-CoV-2 detection. In this study, we improved the RT-PCR by proposing a novel method using dual double-quenched fluorescence probes. We used the improved probes to detect the plasmid DNA and RNA reference materials of SARS-CoV-2, respectively. The results show that, the background fluorescence intensity reduced by 50%, the fluorescence increment increased to 2.8 folds, and the Ct value significantly reduced by 3 or more, indicating that the detection sensitivity increased at least 8 times. In addition, we demonstrated that the improved probes have well performance in detecting SARS-CoV-2, with the minimum concentration of 6.2 copies/µL. This study will help biological companies develop better products for SARS-CoV-2 and other clinical pathogen infection.