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Molecular characterization of human factor XSan Antonio 总被引:1,自引:0,他引:1
Enzymatic amplification technique was used to isolate all eight exons and sequences around the splice junctions, putative promoter, and polyadenylation sites of human factor X DNA from a patient with factor X deficiency. Two genetic changes in factor X have been observed in this patient. The patient is most likely a compound heterozygote since there is only 14% activity associated with factor X. A point mutation that resulted in the substitution of cysteine (TGC) for arginine (CGC) at amino acid 366 was found in exon VIII of one allele of the factor X gene. This mutation, which occurs in the catalytic domain, can affect the formation of a disulfide bridge and thus could result in a reduction in factor X activity. Sequencing all the regions revealed a second mutation: a deletion of one nucleotide (TCCT to TCT) in exon VII that would cause a frame shift at amino acid 272 followed by termination. We have also shown that the point mutation in exon VIII creates an ApaL1 restriction site and destroys the HinP1 site. Enzymatic DNA amplification followed by restriction digestion provides a quick, reliable, and sensitive method for carrier detection and antenatal diagnosis in affected kindreds. This is the first characterization of factor X deficiency at the molecular level. We propose to name this mutation Factor XSan Antonio. 相似文献
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Activation of the coagulation cascade after infusion of a factor XI concentrate in congenitally deficient patients 总被引:5,自引:1,他引:5
Mannucci PM; Bauer KA; Santagostino E; Faioni E; Barzegar S; Coppola R; Rosenberg RD 《Blood》1994,84(4):1314-1319
Virally inactivated, high-purity factor XI concentrates are available for treatment of patients with factor XI deficiency. However, preliminary experience indicates that some preparations may be thrombogenic. We evaluated whether a highly purified concentrate produced signs of activation of the coagulation cascade in two patients with severe factor XI deficiency infused before and after surgery. Signs of heightened enzymatic activity of the common pathway of coagulation (elevated plasma levels of prothrombin fragment 1 + 2 and fibrinopeptide A) developed in the early post-infusion period, accompanied by more delayed signs of fibrin formation with secondary hyperfibrinolysis (elevated D-dimer and plasmin-antiplasmin complex). These changes occurred in both patients, but were more severe in the older patient with breast cancer when she underwent surgery, being accompanied by fibrinogen and platelet consumption. There were no concomitant signs of heightened activity of the factor VII-tissue factor mechanism on the factor Xase complex (plasma levels of activated factor VII and of factor IX and X activation peptides did not increase). The observed changes in biochemical markers of coagulation activation indicate that concentrate infusions increased thrombin generation and activity and that such changes were magnified by malignancy and surgery. Because some factor XI concentrates may be thrombogenic, they should be used with caution, especially in patients with other risk factors for thrombosis. 相似文献
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Antonella Napolitano Renata Zanin Federica Palma Cecilia Romani Giovanni Grandi Costantino Di Carlo 《The European journal of contraception & reproductive health care》2016,21(2):168-175
Objective The effect on body composition and in particular on fat mass (FM) of 12 months’ use of a desogestrel (DSG)-only contraceptive pill or the levonorgestrel-releasing intrauterine system (LNG-IUS) was evaluated in women in the perimenopause.Methods An observational study comprised 102 perimenopausal women: 42 received a 75 μg DSG pill, 34 received the 52 mg LNG-IUS, and 26 received no treatment. Body composition, body weight and resting metabolic rate (RMR) were evaluated at baseline and again after 12 months.Results FM did not change in the control group (? 0.5 ± 1.6%) but significantly increased in the LNG-IUS group (+ 1.1 ± 2.9%; p = 0.02 vs. controls) and in the DSG group (+ 2.8 ± 3.5%; p = 0.0001 vs. controls; p = 0.02 vs. LNG-IUS). Women treated with DSG or the LNG-IUS showed a non-significant increase in body weight, body mass index and waist circumference. RMR did not significantly vary in the control group (? 3.8 ± 292.9 kJ/ 24 h) and tended to decrease but not significantly in the LNG-IUS (115.5 ± 531.8 kJ/ 24 h) and DSG groups (305.9 ± 556.9 kJ/24 h).Conclusions The results of this preliminary study seem to indicate that in perimenopausal women continuous use of the DSG-only pill and to a lesser extent the LNG-IUS may favour FM accumulation. 相似文献
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目的分析先天性肠闭锁病例的诊断及治疗,以提高治愈率及术后生活质量。方法回顾性分析166例先天性肠闭锁的临床资料。结果治愈142例,治愈率85.5%(142/166),其中包括18例二期手术治愈者;术中10例、术后8例放弃治疗;术后死亡6例。结论早期诊断和选择合理的术式是提高肠闭锁治愈率的关键,基础支持及手术技术改进能促进病情的恢复,改善预后。 相似文献
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Sara Artusi Emanuela Ruggiero Matteo Nadai Beatrice Tosoni Rosalba Perrone Annalisa Ferino Irene Zanin Luigi Xodo Louis Flamand Sara N. Richter 《Viruses》2021,13(2)
The herpes simplex virus 1 (HSV-1) genome is extremely rich in guanine tracts that fold into G-quadruplexes (G4s), nucleic acid secondary structures implicated in key biological functions. Viral G4s were visualized in HSV-1 infected cells, with massive virus cycle-dependent G4-formation peaking during viral DNA replication. Small molecules that specifically interact with G4s have been shown to inhibit HSV-1 DNA replication. We here investigated the antiviral activity of TMPyP4, a porphyrin known to interact with G4s. The analogue TMPyP2, with lower G4 affinity, was used as control. We showed by biophysical analysis that TMPyP4 interacts with HSV-1 G4s, and inhibits polymerase progression in vitro; in infected cells, it displayed good antiviral activity which, however, was independent of inhibition of virus DNA replication or entry. At low TMPyP4 concentration, the virus released by the cells was almost null, while inside the cell virus amounts were at control levels. TEM analysis showed that virus particles were trapped inside cytoplasmatic vesicles, which could not be ascribed to autophagy, as proven by RT-qPCR, western blot, and immunofluorescence analysis. Our data indicate a unique mechanism of action of TMPyP4 against HSV-1, and suggest the unprecedented involvement of currently unknown G4s in viral or antiviral cellular defense pathways. 相似文献
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Debora Bevilaqua-Grossi Marilia Zanin Camila Benedetti Lidiane Florencio Anamaria Oliveira 《Physiotherapy theory and practice》2019,35(2):139-147
Objective: The aim was to assess sensitization using quantitative sensory testing in mechanical and thermal modes in individuals with and without osteoarthritis (OA) of the knee. Pain thresholds were correlated with functionality, symptoms of depression and intensity of pain. Methods: Thirty control volunteers and 30 patients with OA of the knee were assessed. Punctate pain thresholds using Von Frey filaments and thermal pain thresholds using a Thermal Sensory Analyzer were evaluated in the periarticular region of the knee and forearm. Using a digital pressure algometer, pressure pain thresholds were assessed in the periarticular region of the knee and on the root exit zone on the lumbar and sacral spine. Results: Punctate, pressure, and thermal pain thresholds differed significantly between participants with and without OA (p < 0.05). Values in those with OA were consistent with pain sensitization. Pressure pain thresholds also showed moderate and negative correlations with data on functionality, symptoms of depression and intensity of pain (?0.36 < r > ?0.56), contributing up to 30% of their variability. Conclusions: Allodynia and hyperalgesia were demonstrated in the OA group, suggesting central sensitization in patients with mild to moderate severity of joint damage. Correlation between mechanical hypersensitivity and psychosocial factors seems to be small, despite of its significance. 相似文献
40.
Analogues of oxytocin and deaminooxytocin with 4-glutamine replaced by 4-glutamic acid methyl ester readily lose their uterotonic activity when incubated with rat serum, presumably by hydrolysis to the much less active 4-glutamic acid derivatives. On the other hand, inactivation of the deaminooxytocin analogue in the rat uterus, as demonstrated by the 'oil-bath'technique, is only slightly more rapid than that of deaminooxytocin and distinctly slower than that of oxytocin. Its in situ/in vitro ratio of uterotonic activity is less than 0.1 whereas that for deaminooxytocin is about 3 and also the persistence of the uterotonic effect in situ is slightly less than that of deaminooxytocin. The results with these 'rapidly inactivated'analogues can be used as proof of some predictions of the three-compartment model for tissue distribution of neurohypophysial hormones and its influence upon the time course of a biological response published earlier. The potential use of analogues of neurohypophysial hormones as probes for inactivation mechanisms and the results thus far obtained are discussed. 相似文献