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31.
In addition to the established association between high lipoprotein(a) [Lp(a)] concentrations and coronary artery disease, an association between Lp(a) and venous thromboembolism (VTE) has also been described. Lp(a) is controlled by genetic variants in LPA gene, coding for apolipoprotein(a), including the kringle-IV type 2 (KIV-2) size polymorphism. Aim of the study was to investigate the role of LPA gene KIV-2 size polymorphism and single nucleotide polymorphisms (SNPs) (rs1853021, rs1800769, rs3798220, rs10455872) in modulating VTE susceptibility. Five hundred and sixteen patients with VTE without hereditary and acquired thrombophilia and 1117 healthy control subjects, comparable for age and sex, were investigated. LPA KIV-2 polymorphism, rs3798220 and rs10455872 SNPs were genotyped by TaqMan technology. Concerning rs1853021 and rs1800769 SNPs, PCR-RFLP assay was used. LPA KIV-2 repeat number was significantly lower in patients than in controls [median (interquartile range) 11(6–17) vs 15(9–25), p<0.0001]. A significantly higher prevalence of KIV-2 repeat number ≤7 was observed in patients than in controls (33.5% vs 15.5%, p<0.0001). KIV-2 repeat number was independently associated with VTE (p = 4.36 x10-9), as evidenced by the general linear model analysis adjusted for transient risk factors. No significant difference in allele frequency for all SNPs investigated was observed. Haplotype analysis showed that LPA haplotypes rather than individual SNPs influenced disease susceptibility. Receiver operating characteristic curves analysis showed that a combined risk prediction model, including KIV-2 size polymorphism and clinical variables, had a higher performance in identifying subjects at VTE risk than a clinical-only model, also separately in men and women.  相似文献   
32.
The growing commercial interest in multi-strain formulations marketed as probiotics has not been accompanied by an equal increase in the evaluation of quality levels of these biotechnological products. The multi-strain product VSL#3 was used as a model to setup a microbiological characterization that could be extended to other formulations with high complexity. Shotgun metagenomics by deep Illumina sequencing was applied to DNA isolated from the commercial VSL#3 product to confirm strains identity safety and composition. Single-cell analysis was used to evaluate the cell viability, and β-galactosidase and urease activity have been used as marker to monitor the reproducibility of the production process. Similarly, these lots were characterized in detail by a metaproteomics approach for which a robust protein extraction protocol was combined with advanced mass spectrometry. The results identified over 1600 protein groups belonging to all strains present in the VSL#3 formulation. Of interest, only 3.2 % proteins showed significant differences mainly related to small variations in strain abundance. The protocols developed in this study addressed several quality criteria that are relevant for marketed multi-strain products and these represent the first efforts to define the quality of complex probiotic formulations such as VSL#3.  相似文献   
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34.
Coagulation factor XI (FXI) is the zymogen of a serine protease that, when converted to its active form, contributes to blood coagulation through proteolytic activation of factor IX. FXI deficiency is typically an autosomal recessive disorder, characterized by bleeding symptoms mainly associated with injury or surgery. Of the more than 100 FXI gene mutations reported in FXI-deficient patients, most are associated with a proportional decrease in FXI functional and immunologic levels (type I defects), whereas only a few mutations leading to the presence of dysfunctional molecules in plasma have been molecularly analyzed to date (type II deficiencies). We report the functional and molecular characterization of a missense mutation (Val371Ile) identified, in the heterozygous state, in a 25-year-old Italian male with mild FXI deficiency. Laboratory analysis revealed reduced functional FXI levels (34%), but normal antigen levels (102%), distinctive of a type II defect. Given the proximity of Val371 to the FXI activation site, a possible interference with zymogen activation was postulated. Expression experiments of the FXI-Val371Ile recombinant protein, followed by activation assays, showed both a different time course in FXI activation and a slight delay in factor IX activation by thrombin-activated FXI.  相似文献   
35.
The insulin-like growth factor type 1 receptor (IGF-1R) is part of the receptor tyrosine kinase superfamily. The activation of IGF-1R regulates several key signaling pathways responsible for maintaining cellular homeostasis, including survival, growth, and proliferation. In addition to mediating signal transduction at the plasma membrane, in serum-based models, IGF-1R undergoes SUMOylation by SUMO 1 and translocates to the nucleus in response to IGF-1. In corneal epithelial cells grown in serum-free culture, however, IGF-1R has been shown to accumulate in the nucleus independent of IGF-1. In this study, we report that the insulin-like growth factor binding protein-3 (IGFBP-3) mediates nuclear translocation of IGF-1R in response to growth factor withdrawal. This occurs via SUMOylation by SUMO 2/3. Further, IGF-1R and IGFBP-3 undergo reciprocal regulation independent of PI3k/Akt signaling. Thus, under healthy growth conditions, IGFBP-3 functions as a gatekeeper to arrest the cell cycle in G0/G1, but does not alter mitochondrial respiration in cultured cells. When stressed, IGFBP-3 functions as a caretaker to maintain levels of IGF-1R in the nucleus. These results demonstrate mutual regulation between IGF-1R and IGFBP-3 to maintain cell survival under stress. This is the first study to show a direct relationship between IGF-1R and IGFBP-3 in the maintenance of corneal epithelial homeostasis.  相似文献   
36.
BACKGROUND: In mouse models of retinopathy of prematurity (ROP) inhibitors of vascular endothelial growth factor (VEGF) functions administered systemically completely block retinal neovascularization. In contrast, selective ocular VEGF depletion has achieved an approx. 50% inhibition of retinal neovascular growth. It is unclear whether a more complete inhibition of new blood vessel development can be obtained with an anti-VEGF therapy localized to the eye. Therefore, the objective of the present study was to determine the effect of local anti-VEGF therapy in a different animal model which closely mimics human ROP. METHODS: Rats were exposed to alternating cycles of high and low levels of oxygen for 14 days immediately after birth; thereafter, they were intravitreally injected with an adenoviral vector expressing a secreted form of the VEGF receptor flt-1 (Ad.sflt), which acts by sequestering VEGF. Contralateral eyes were injected with the control vector carrying the reporter gene expressing beta-galactosidase (Ad.betaGal). RESULTS: At the peak of retinal neovascular growth, i.e. post-natal day 21 (P21), we observed up to 97.5% decrease in retinal neovascularization in animals injected with Ad.sflt. At the end of observation (P28), no significant difference in retinal vessel number was detected in both oxygen-injured and normoxic Ad.sflt-treated retinas compared with untreated or Ad.betaGal-treated retinas. CONCLUSION: Adenoviral-mediated sflt-1 gene transfer induces a near-complete inhibition of ischemia-induced retinal neovascularization in rats without affecting pre-existing retinal vessels.  相似文献   
37.
The systems that the 3-amino derivative of beta-cyclodextrin (CD3NH2) forms with the proton, the copper(II) ion and each of the enantiomers of certain amino acids (alanine, phenylalanine, tyrosine and tryptophan) were investigated. The enantioselectivity shown by the potentiometric measurements carried out on the phenylalanine ternary systems was exploited in capillary electrophoresis by ligand exchange capillary electrophoresis (LECE) to obtain the separation of phenylalanine racemate. The tyrosine racemate was also separated by LECE. The comparison between thermodynamic and capillary electrophoresis (CE) results is discussed, in order to get a better insight into the separation mechanism.  相似文献   
38.
The aim of this study was to identify a simple, rapid method for sex determination of in vitro produced buffalo embryos, amplifying Y-chromosome-specific repeat sequences by polymerase chain reaction (PCR). Buffalo oocytes collected from slaughtered animals were matured, fertilised and cultured in vitro for 7 days. On day 7 embryos were evaluated and divided in to six groups according to developmental stage (2, 4, 8, 16 cells, morulae and blastocyst). Each embryo was stored singly in phosphate-buffered saline at -20 degrees C until PCR. Two different methods of extraction of DNA were compared: a standard procedure (ST), using a normal extraction by phenol-chloroform, isoamyl alcohol and final precipitation in absolute ethanol and a direct procedure (DT), using a commercial kit (Qiaquik-Qiagen mini blood). A pair of bovine satellite primers and two pairs of different bovine Y-chromosome-specific primers (BRY4.a and BRY.1) were used in the PCR assay on embryos and on whole blood samples collected from male and female adult buffaloes, used as control. The trial was carried out on 359 embryos (193 for ST and 166 for DT). When DNA samples from blood were amplified, the sex determined by PCR always corresponded to the anatomical sex. Embryo sexing was not possible in two embryos in ST and one embryo in DT. Both extraction protocols recovered sufficient quantities of target DNA at all developmental stages, but the time required for the ST (24 h) limits its use in embryo sexing and supports the use of commercial extraction kits (5 h).  相似文献   
39.
Aminoglycoside antibiotics that bind to 16S ribosomal RNA in the aminoacyl-tRNA site (A site) cause misreading of the genetic code and inhibit translocation. Structures of an A site RNA oligonucleotide free in solution and bound to the aminoglycosides paromomycin or gentamicin C1a have been determined by NMR. Recently, the X-ray crystal structure of the entire 30S subunit has been determined, free and bound to paromomycin. Distinct differences were observed in the crystal structure, particularly at A1493. Here, the NMR structure of the oligonucleotide-paromomycin complex was determined with higher precision and is compared with the X-ray crystal structure of the 30S subunit complex. The comparison shows the validity of both structures in identifying critical interactions that affect ribosome function.  相似文献   
40.
The aim in this study was to compare two estrus synchronization protocols in buffaloes. Animals were divided into two groups: Group A (n=111) received 100 microg GnRH on Day 0, 375 microg PGF(2alpha) on Day 7 and 100 microg GnRH on Day 9 (Ovsynch); Group B (n=117) received an intravaginal drug release device (PRID) containing 1.55 g progesterone and a capsule with 10mg estradiol benzoate for 10 days and were treated with a luteolytic dose of PGF(2alpha) and 1000 IU PMSG at the time of PRID withdrawal. Animals were inseminated twice 18 and 42 h after the second injection of GnRH (Group A) and 60 and 84 h after PGF(2alpha) and PMSG injections (Group B). Progesterone (P(4)) concentrations in milk samples collected 12 and 2 days before treatments were used to determine cyclic and non-cyclic buffaloes, and milk P(4) concentrations 10 days after Artificial insemination (AI) were used as an index of a functional corpus luteum. Cows were palpated per rectum at 40 and 90 days after AI to determine pregnancies. All previously non-cyclic animals in Group B had elevated P(4) (>120 pg/ml milk whey) on Day 10 after AI. Accordingly, a greater (P<0.01) relative percentage of animals with elevated P(4) 10 days after AI were observed in Group B (93.2%) than in Group A (81.1%). However, there was no difference in overall pregnancy rates between the two estrus synchronization protocols (Group A, 36.0%; Group B 28.2%). When only animals with elevated P(4) on Day 10 after AI were considered, pregnancy rate was higher (P<0.05) for animals in Group A (44.4%) than Group B (30.3%). The findings indicated that treatment with PRID can induce ovulation in non-cyclic buffalo cows. However, synchronization of estrus with Ovsynch resulted in a higher pregnancy rate compared with synchronization with PRID, particularly in cyclic buffalo.  相似文献   
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