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61.
Melusin,a muscle-specific integrin beta1-interacting protein,is required to prevent cardiac failure in response to chronic pressure overload 总被引:13,自引:0,他引:13
Brancaccio M Fratta L Notte A Hirsch E Poulet R Guazzone S De Acetis M Vecchione C Marino G Altruda F Silengo L Tarone G Lembo G 《Nature medicine》2003,9(1):68-75
Cardiac hypertrophy is an adaptive response to a variety of mechanical and hormonal stimuli, and represents an early event in the clinical course leading to heart failure. By gene inactivation, we demonstrate here a crucial role of melusin, a muscle-specific protein that interacts with the integrin beta1 cytoplasmic domain, in the hypertrophic response to mechanical overload. Melusin-null mice showed normal cardiac structure and function in physiological conditions, but when subjected to pressure overload--a condition that induces a hypertrophic response in wild-type controls--they developed an abnormal cardiac remodeling that evolved into dilated cardiomyopathy and contractile dysfunction. In contrast, the hypertrophic response was identical in wild-type and melusin-null mice after chronic administration of angiotensin II or phenylephrine at doses that do not increase blood pressure--that is, in the absence of cardiac biomechanical stress. Analysis of intracellular signaling events induced by pressure overload indicated that phosphorylation of glycogen synthase kinase-3beta (GSK-3beta) was specifically blunted in melusin-null hearts. Thus, melusin prevents cardiac dilation during chronic pressure overload by specifically sensing mechanical stress. 相似文献
62.
Association of the low-density lipoprotein receptor gene with obesity in Native American populations 总被引:3,自引:0,他引:3
Five low-density lipoprotein receptor gene (LDLR) restriction fragment length polymorphisms (RFLPs: TaqI, intron 4; HincII, exon 12; AvaII, exon 13; MspI and NcoI, exon 18) were investigated in 131 individuals from five Brazilian Indian tribes. All markers were polymorphic in this ethnic group. In the whole sample of Amerindians, 13 (41%) of the 32 expected haplotypes were identified, but only three were shared by all tribes. The Xavante, Suruí, Zoró, and Gavi?o tribes, who had been studied for anthropometry, were grouped according to their genotypes, and the corresponding mean values were examined. Significant associations were observed between HincII *H-, AvaII *A+, MspI *M-, and NcoI *N+ and the body mass index (BMI), triceps and subscapular skinfolds, and the arm fat index (AFI). Haplotypes were derived for these four RFLPs, and (*H-/*A+/*M-/*N+) haplotype carriers were compared with noncarriers of this haplotype with equally significant results for the three parameters (BMI, P=0.021; skinfold thickness, P<0.001; AFI, P=0.005). These results suggest that the LDLR gene has some influence over adipose tissue deposition. 相似文献
63.
Erika Souza Vieira Tâmara Karoline de Oliveira Fontes Matheus Mendonça Pereira Hofsky Vieira Alexandre Daniel Pereira da Silva Cleide Mara Faria Soares Álvaro Silva Lima 《Bioprocess and biosystems engineering》2015,38(4):721-728
A novel strategy for the production of lipase by Bacillus sp. ITP-001 in a stirred tank fermenter using perfluorodecalin (PFD) was studied. Firstly, a response surface methodology 22 with three central points was employed to optimise the effect of agitation speed and aeration rate in lipase production. According to the response from the experimental designs, 300 rpm (revolutions per minute) and 0.5 vvm (air volume/liquid volume per minute) were found to provide the best condition (lipolytic activity: LA = 3,140.76 U mL?1). Then, the influence of PFD concentration on the fermentation process was evaluated. Incorporation of PFD at all concentrations above 1 % had no statistically significant influence on lipase production, that is, the previous optimisation allowed the reduction of the amount of PFD added besides increasing lipase production. Furthermore, PFD could be used in three sequential fermentations without altering the statistical production of lipase, reducing by 67 % the cost of PFD addition. 相似文献
64.
Ivana Cacciatore Mara Di Giulio Erika Fornasari Antonio Di Stefano Laura Serafina Cerasa Lisa Marinelli Hasan Turkez Emanuela Di Campli Soraya Di Bartolomeo Iole Robuffo Luigina Cellini 《PloS one》2015,10(4)
Objective
The increasing prevalence of antibiotic-resistant bacterial infections led to identify alternative strategies for a novel therapeutic approach. In this study, we synthesized ten carvacrol codrugs – obtained linking the carvacrol hydroxyl group to the carboxyl moiety of sulphur-containing amino acids via an ester bond – to develop novel compounds with improved antimicrobial and antibiofilm activities and reduced toxicity respect to carvacrol alone.Method
All carvacrol codrugs were screened against a representative panel of Gram positive (S. aureus and S. epidermidis), Gram negative (E. coli and P. aeruginosa) bacterial strains and C. albicans, using broth microdilution assays.Findings
Results showed that carvacrol codrug 4 possesses the most notable enhancement in the anti-bacterial activity displaying MIC and MBC values equal to 2.5 mg/mL for all bacterial strains, except for P. aeruginosa ATCC 9027 (MIC and MBC values equal to 5 mg/mL and 10 mg/mL, respectively). All carvacrol codrugs 1-10 revealed good antifungal activity against C. albicans ATCC 10231. The cytotoxicity assay showed that the novel carvacrol codrugs did not produce human blood hemolysis at their MIC values except for codrugs 8 and 9. In particular, deepened experiments performed on carvacrol codrug 4 showed an interesting antimicrobial effect on the mature biofilm produced by E. coli ATCC 8739, respect to the carvacrol alone. The antimicrobial effects of carvacrol codrug 4 were also analyzed by TEM evidencing morphological modifications in S. aureus, E. coli, and C. albicans.Conclusion
The current study presents an insight into the use of codrug strategy for developing carvacrol derivatives with antibacterial and antibiofilm potentials, and reduced cytotoxicity. 相似文献65.
Elisa Rossi Daniela Basso Carlo-Federico Zambon Filippo Navaglia Eliana Greco Michela Pelloso Serena Artuso Andrea Padoan Matilde Pescarin Ada Aita Dania Bozzato Stefania Moz Mara Cananzi Graziella Guariso Mario Plebani 《PloS one》2015,10(4)
Background
TNF-α and IFN-γ play a role in the development of mucosal damage in celiac disease (CD). Polymorphisms of TNFA and IFNG genes, as well as of the TNFRSF1A gene, encoding the TNF-α receptor 1, might underlie different inter-individual disease susceptibility over a common HLA risk background. The aims of this study were to ascertain whether five SNPs in the TNFA promoter (-1031T>C,-857C>T,-376G>A,-308G>A,-238G>A), sequence variants of the TNFRSF1A gene and IFNG +874A>T polymorphism are associated with CD in a HLA independent manner.Methods
511 children (244 CD, 267 controls) were genotyped for HLA, TNFA and INFG (Real Time PCR). TNFRSF1A variants were studied (DHPLC and sequence).Results
Only the rare TNFA-1031C (OR=0.65, 95% CI:0.44-0.95), -857T (OR=0.42, 95% CI:0.27-0.65), -376A (OR=2.25, 95% CI:1.12-4.51) and -308A (OR=4.76, 95% CI:3.12-7.26) alleles were significantly associated with CD. One TNFRSF1A variant was identified (c.625+10A>G, rs1800693), but not associated with CD. The CD-correlated TNFA SNPs resulted in six haplotypes. Two haplotypes were control-associated (CCGG and TTGG) and three were CD-associated (CCAG, TCGA and CCGA). The seventeen inferred haplotype combinations were grouped (A to E) based on their frequencies among CD. Binary logistic regression analysis documented a strong association between CD and HLA (OR for intermediate risk haplotypes=178; 95% CI:24-1317; OR for high risk haplotypes=2752; 95% CI:287-26387), but also an HLA-independent correlation between CD and TNFA haplotype combination groups. The CD risk for patients carrying an intermediate risk HLA haplotype could be sub-stratified by TNFA haplotype combinations.Conclusion
TNFA promoter haplotypes associate with CD independently from HLA. We suggest that their evaluation might enhance the accuracy in estimating the CD genetic risk. 相似文献66.
Enhanced extraction of proteins using cholinium‐based ionic liquids as phase‐forming components of aqueous biphasic systems 下载免费PDF全文
Maria V. Quental Magda Caban Matheus M. Pereira Piotr Stepnowski João A. P. Coutinho Mara G. Freire 《Biotechnology journal》2015,10(9):1457-1466
Aqueous biphasic systems (ABS) composed of ionic liquids (ILs) are promising platforms for the extraction and purification of proteins. In this work, a series of alternative and biocompatible ABS composed of cholinium‐based ILs and polypropylene glycol were investigated. The respective ternary phase diagrams, tie‐lines, tie‐line lengths and critical points were determined at 25°C. The extraction performance of these systems for commercial bovine serum albumin (BSA) was then evaluated. The stability of BSA at the IL‐rich phase was ascertained by size exclusion high‐performance liquid chromatography and Fourier transform infrared spectroscopy. Appropriate ILs lead to the complete extraction of BSA for the IL‐rich phase, in a single step, while maintaining the protein's native conformation. Furthermore, to evaluate the performance of these systems when applied to real matrices, the extraction of BSA from bovine serum was additionally carried out, revealing that the complete extraction of BSA was maintained and achieved in a single step. The remarkable extraction efficiencies obtained are far superior to those observed with typical polymer‐based ABS. Therefore, the proposed ABS may be envisaged as a more effective and biocompatible approach for the separation and purification of other value‐added proteins. 相似文献
67.
Recombinase‐mediated cassette exchange (RMCE) for monoclonal antibody expression in the commercially relevant CHOK1SV cell line 下载免费PDF全文
Lin Zhang Mara C. Inniss Shu Han Mark Moffat Heather Jones Baohong Zhang Wendy L. Cox James R. Rance Robert J. Young 《Biotechnology progress》2015,31(6):1645-1656
To meet product quality and cost parameters for therapeutic monoclonal antibody (mAb) production, cell lines are required to have excellent growth, stability, and productivity characteristics. In particular, cell line generation stability is critical to the success of a program, especially where high cell line generation numbers are required for large in‐market supply. However, a typical process for developing such cell lines is laborious, lengthy, and costly. In this study, we applied a FLP/FRT recombinase‐mediated cassette exchange (RMCE) system to build a site‐specific integration (SSI) system for mAb expression in the commercially relevant CHOK1SV cell line. Using a vector with a FRT‐flanked mAb expression cassette, we generated a clonal cell line with good productivity, long‐term production stability, and low mAb gene‐copy number indicating the vector was located in a ‘hot‐spot.’ A SSI host cell line was made by removing the mAb genes from the ‘hot‐spot’ by RMCE, creating a ‘landing pad’ containing two recombination cassettes that allow targeting of one or two copies of recombinant genes. Cell lines made from this host exhibited excellent growth and productivity profiles, and stability for at least 100 generations in the absence of selection agents. Importantly, while clones containing two copies had higher productivity than single copy clones, both were stable over many generations. Taken together, this study suggests the use of FLP‐based RMCE to develop SSI host cells for mAb production in CHOK1SV offers significant savings in both resources and overall cell line development time, leading to a shortened ‘time‐to‐clinic’ for therapeutic mAbs. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1645–1656, 2015 相似文献
68.
Caterina Longo Simonetta Piana Aimilios Lallas Elvira Moscarella Mara Lombardi Margherita Raucci Giovanni Pellacani Giuseppe Argenziano 《PloS one》2015,10(9)
Background
Several studies have demonstrated the benefit of integrating clinical with pathologic information, to obtain a confident diagnosis for melanocytic tumors. However, all those studies were conducted retrospectively and no data are currently available about the role of a clinical-pathologic correlation approach on a daily basis in clinical practice.Aim of the Study
In our study, we evaluated the impact of a routine clinical-pathologic correlation approach for difficult skin tumors seen over 3 years in a tertiary referral center.Results
Interestingly, a re-appraisal was requested for 158 out of 2015 (7.7%) excised lesions because clinical-pathologic correlation was missing. Of note, in 0.6% of them (13 out of 2045) the first histologic diagnosis was revised in the light of clinical information that assisted the Pathologist to re-evaluate the histopathologic findings that might be bland or inconspicuous per se.Conclusion
In conclusion, our study demonstrated that an integrated approach involving clinicians and pathologists allows improving management of selected patients by shifting from a simply disease-focused management (melanoma versus nevus) to a patient-centered approach. 相似文献69.
Diţu LM Mihăescu G Chifiriuc C Bleotu C Morusciag L Niţulescu GM Missir A 《Roumanian archives of microbiology and immunology》2010,69(1):41-47
The qualitative screening of the susceptibility spectra of different microbial strains to the newly synthesized substances complexes was performed by adapted disk diffusion techniques, while the quantitative assay of the minimal inhibitory concentration (M.I.C., microg/cm3) value was based on liquid medium serial microdilutions. The compounds were solubilized in dimethylsulfoxide (DMSO). The in vitro biological screening effects were tested against a microbial inoculum of approximately 1.5 x 10(8) UFC/cm3, corresponding to 0.5 McFarland standard density, obtained from Gram positive (Staphylococcus aureus, Bacillus subtilis), Gram negative bacteria (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa) and fungal strains (Candida albicans). In order to investigate the influence of the subinhibitory concentration of the tested substances on the expression of different virulence features, the strains were incubated overnight in the presence of the newly synthesized thiourea derivatives (vol:vol) and different virulence features were investigated, i.e: adherence capacity to the cellular substrate represented by HeLa cells and to inert substrata quantified by slime test and soluble enzymatic virulence factors (haemolysins and other pore-forming toxins, proteases activity, DN-ase and siderophores production). The cytotoxicity was assessed microscopically, by observing the effect of the tested compounds on the cellular substratum integrity. 相似文献
70.
Luciana Tovo‐Rodrigues Sidia M. Callegari‐Jacques M. Luiza Petzl‐Erler Luiza Tsuneto Francisco M. Salzano Mara H. Hutz 《American journal of physical anthropology》2010,143(3):458-464
The DRD4 variable number of tandem repeats (VNTR) allele distribution of 172 Guarani (Kaiowá and Ñandeva subgroups) and Kaingang Brazilian Amerindians is reported. These results are integrated with those previously obtained for this ethnic group. Allele frequencies for the three populations are within the interval observed for 15 other Native American populations and show intermediate values between those observed in Amazonia and Patagonia. Significant differences in allele distribution between recent past hunter–gatherer and agriculturalist populations are observed, with an increase of the 7R allele among hunter–gatherers (P < 0.001). Analysis of molecular variance (AMOVA) and pairwise FST data suggest three distinct sectors for the genetic landscape of Native South America: Andes, Center/Southeast region, and Amazonia. Common traits among hunter–gatherers such as novelty‐seeking temperament, hyperactivity, and impulsivity could have been important and advantageous in new environments during America's prehistoric colonization. Am J Phys Anthropol, 2010. © 2010 Wiley‐Liss, Inc. 相似文献