[Phenotypic and genetic analysis of a Chinese pedigree affected with Hereditary antithrombin deficiency due to a novel variant of SERPINC1 gene].

OBJECTIVE: To analyze the clinical phenotype and genetic characteristics of a Chinese pedigree affected with Hereditary antithrombin deficiency. METHODS: A pedigree diagnosed at the the Second Affiliated Hospital of Wenzhou Medical University, Yuying Children's Hospital in June, 2020 was selected as the study subject. Plasma prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), and thrombin time (TT) of the probands and their pedigree members were determined using a STA-R automatic coagulation analyzer. Antithrombin activity (AT: A) and antithrombin antigen (AT: Ag) in plasma were determined with chromogenic substrate and immunonephelometry assays. All exons and flanking sequences of the anticoagulant protein gene SERPINC1 were amplified by PCR and subjected to Sanger sequencing. Candidate variants were verified with bioinformatic tools (PolyPhen-2, SIFT, Mutation Taster and PYMOL) to explore their effect on the function and structural conformation of the protein. RESULTS: The probands (II-2, II-10), their brother (II-5) and sons (III-1, III-8) had shown normal PT, APTT, FIB, and TT, but significantly decreased AT: A and AT: Ag, with their levels being 34%, 57%, 56%, 48%, 53% and 13.51 mg/dL, 13.44 mg/dL, 18.39 mg/dL, 17.36 mg/dL, 17.71 mg/dL, respectively. The remaining pedigree members had normal values. Sanger sequencing revealed that the probands and all affected pedigree members had harbored a heterozygous c.851T>C (p.Met284Thr) missense variant in exon 5 of the SERPINC1 gene. Bioinformatic analysis and simulation suggested that the variant has resulted in alteration of hydrogen bonds at the c.851 position, which may affect the structure of the protein. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was classified as pathogenic (PS1+PM1+PM5+PP1+PP4). CONCLUSION: The probands and other affected members were all diagnosed with type I hereditary AT deficiency, for which the c.851T>C (p.Met284Thr) variant of the SERPINC1 gene may be accountable.

Phenotypic and genetic analyses of four cases of coagulation factor XII deficiency.

OBJECTIVES: To identify the clinical phenotypic and molecular pathogeneses of four cases of coagulation factor XII deficiency and to deepen the cognition of this disease. METHODS: Coagulation tests were performed through one stage of coagulation on a STAGO coagulation analyser. Coagulation factor XII antigen was detected using enzyme-linked immunosorbent assay. The species conservatism and structural change of mutant proteins were analysed using MegAlign and PYMOL. Meanwhile, missense variants and a novel splice site variant were identified using PolyPhen2 and NetGene2. RESULTS: The four cases had an observably prolonged activated partial thromboplastin time but without obvious bleeding tendency. Their coagulation factor XII activity (FⅫ:C) and antigen (FXII:Ag) were greatly reduced. Six mutations were detected: NM_000505.4:c.398-1G>A, NP_000496.2:p.(Pro182Leu), NP_000496.2:p.(Ser479Ter), NP_000496.2:p.(Cys559Arg), NC_000005.10:g.7217_7221delinsGTCTA and NM_000505.4:c.1681-1G>A. The first five are newly discovered mutations. The two missense mutation sites were highly conservative, and their protein secondary structure changes may occur not only on the mutation sites but also on other domains. In silico analysis revealed that NP_000496.2:p.(Pro182Leu) may be BENIGN, NP_000496.2:p.(Cys559Arg) may be damaging, and that NM_000505.4:c.398-1G>A and NM_000505.4:c.1681-1G>A are crucial for splicing. CONCLUSION: We found six types of mutations, of which five were novel. The two missense mutation sites might be closely related to the function of coagulation factor XII. The mutations were the primary culprits of factor XII deficiency.

Economical and easily detectable markers of digestive tumors: platelet parameters.

Aim: This study aimed to evaluate the clinical values of platelet parameters in patients with digestive tumors. Patients & methods: A total of 974 people were classified into three groups: malignant group, patients with digestive malignant tumors; benign group, patients with benign tumors; and normal group: healthy individuals. Results: Compared with the benign and normal groups, the malignant group showed significantly increased platelet count (PLT) and plateletcrit (PCT) and significantly reduced mean platelet volume (MPV) and platelet-large cell rate (P-LCR, p < 0.001). Elevated PLT and PCT and reduced MPV and P-LCR indicated poor overall survival in patients with digestive tumors. Conclusion: PLT, PCT, MPV and P-LCR were proven to be predictive biomarkers for patients with digestive malignant tumors. Elevated PLT and PCT or decreased MPV and P-LCR indicated poor overall survival.

Predictive and prognostic values of preoperative platelet parameters in patients with gynecological tumors.

BACKGROUND: Platelets play a role in tumor cell growth, metastasis, and angiogenesis, and the present study aimed to evaluate diagnostic and prognostic values of platelet parameters in patients with gynecological tumors. METHODS: A total of 1062 women were included. Differences of platelet parameters (platelet count [PLT], plateletcrit [PCT], mean platelet volume [MPV], platelet-large cell rate [P-LCR], and platelet distribution width [PDW]) between different categories were analyzed by nonparametric test. The optimal cutoff value was calculated with receiver operating characteristic analysis. Overall survivals were analyzed with Kaplan-Meier method and log-rank tests for univariate analysis. RESULTS: Platelet count and PCT were significantly increased, and MPV and P-LCR were significantly reduced in malign and benign gynecological tumor groups compared with the controls (P < .001); PDW had no significant differences. There were no significant differences in PLT, PCT, MPV, P-LCR, and PDW between different tumor locations and pathologic types. The optimal cutoff values of PLT, PCT, MPV and P-LCR were 274, 0.26, 10.08, and 24.8 (AUC: 0.661, 0.643, 0.593, 0.562), and PCT had preferable sensibility and specificity (50.84% and 70.42%) in predicting the presence of gynecological tumors. According to survival analysis, increased PLT (≥274 × 109 /L) and PCT (≥0.26), and induced MPV (<10.08 fL) and P-LCR (<24.8%) were associated with shorter overall survival. CONCLUSIONS: Platelet count, PCT, MPV, and P-LCR can be used as preferable auxiliary parameters for predicting the presence of gynecological tumors. Increased PLT and PCT, or decreased MPV and P-LCR indicated a heavier tumor burden and shorter overall survival.

[Analysis of a pedigree affected with congenital dysfibrinogenemia due to a novel Gly31Glu mutation of FGA gene].

OBJECTIVE: To analyze the phenotype and genotype of a pedigree affected with congenital dysfibrinogenemia. METHODS: Liver and kidney functions of the proband and her relatives were determined. Coagulation tests including prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time(TT), fibrin(ogen) degradation products (FDPs), D-dimer(D-D) and the calibration experiment of protamine sulfate of against plasma TT were detected in the proband and her predigree members. The activity and antigen of fibrinogen (Fg) in plasma were measured by Clauss method and immunonephelometry method, respectively. All of the exons and exons-intron boundaries of the three fibrinogen genes (FGA, FGB and FGG) were subjected to PCR amplification and Sanger sequencing. Potential influence of the suspected mutations were analyzed with bioinformatics software including PolyPhen-2, SIFT and Mutation Taster. RESULTS: The proband had normal PT, APTT, FDPs, D-D and prolonged TT (31.8 s). The activity of fibrinogen (Fg) in plasma was significantly decreased but the antigen was normal. Genetic analysis revealed a heterozygous c.92G>A (p.Gly31Glu) mutation in exon 2 of the FGA gene. Family studies revealed that the mother carried the same mutation. Bioinformatic analysis suggested that the mutation may affect the function of Fg Protein. CONCLUSION: The dysfibrinogenemia was probably caused by the novel Gly31Glu mutation of the FGA gene.

Antithrombotic Effect of shRNA Target F12 Mediated by Adeno-Associated Virus.

Coagulation factor XII (FXII) plays a crucial role in thrombosis. Moreover, deficiencies in FXII are not associated with excessive bleeding, and its depletion exhibits satisfactory protective effect on thrombus formation. Several strategies targeting FXII have been applied to inhibit thrombosis formation. In this study, C57BL/6 mice were injected with adeno-associated virus (AAV) to identify the role of short hairpin RNA (shRNA) in thrombosis. Differences in liver FXII, coagulation function, and thrombus formation were detected. The potential side effects of FXII were then evaluated through analysis of tail bleeding, biochemical indices, and pathological sections. Results showed that shRNAs, especially shRNA2, carried by AAV, effectively reduced the expression of FXII. Furthermore, only shRNA2 demonstrated an anti-thrombosis effect on multiple models without hemorrhage and side effects. Hence the novel approach of AAV-based shRNA is specific and safe for inhibiting FXII and thrombosis.