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131.
Ivana Sokolovská Claire Albasi Jean-Pierre Riba Vladimír Báleš 《Bioprocess and biosystems engineering》1998,19(3):179-186
In this study we investigated the influences of aeration, substrate type and concentration on extracellular lipase production in a batch fermentor. The use of air enriched with pure oxygen is the most suitable for the lipase production. Additionally, we found that the presence of fats in the culture broth did not affect the value of the volumetric mass transfer coefficient of oxygen in our system. Olive oil or oleic acid was used as carbon sources. In both cases, the maximal specific rate of growth, μmax, was the same but the highest activity was obtained when 10?g/dm3 of olive oil were used as an initial substrate concentration. 相似文献
132.
In our studies to analyze the structure/function relationships among cytoplasmic and organellar seryl-tRNA synthetases (SerRS), we have characterized a Zea mays cDNA (SerZMm) encoding a protein with significant similarity to prokaryotic SerRS enzymes. To demonstrate the functional identity of SerZMm, the gene sequence encoding the putative mature protein was cloned. This construct complemented in vivo a temperature-sensitive Escherichia coli serS mutant strain. The mature SerZMm protein overexpressed in Escherichia coli efficiently aminoacylated bacterial tRNASer in vitro, while yeast tRNA was a poor substrate. These data identify SerZMm as an organellar maize seryl-tRNA synthetase, the first plant organellar SerRS to be cloned. The analysis of its N-terminal targeting signal suggests a mitochondrial function for the SerZMm protein in maize. 相似文献
133.
Ivana Sirangelo Ettore Bismuto Simona Tavassi G. Irace 《European biophysics journal : EBJ》1998,27(1):27-31
The individual tryptophanyl contributions to the near-ultraviolet circular dichroic activity of apomyoglobin in its native
conformation have been resolved by studying recombinant proteins with single tryptophanyl substitutions. Site-directed mutagenesis
of sperm whale apomyoglobin was performed in order to obtain proteins containing only Trp A-5 or Trp A-12. These amino acid
substitutions have very little effect on the overall globin fold as indicated by comparing the spectroscopic properties of
the mutants with those of the wild type protein. The circular dichroism spectra of the two apomyoglobin mutants in the near
ultraviolet were found to be significantly different, both indole residues having significant activity but of opposite sign.
In particular, Trp A-5 shows the presence of a main positive peak centered near 294 – 295 nm with a marked shoulder at 285
nm, ascribed to the 1LBtransition. The spectrum of the mutant protein containing only Trp A-12 shows a large negative contribution with a minimum
near 283 nm and a marked shoulder at 293 nm. The broadness of the negative contribution exhibited by Trp A-12 suggests that
it may originate mainly from the 1LA transition.
Received: 17 February 1997 / Accepted: 14 August 1997 相似文献
134.
Francesco Taus Marilina B. Santucci Emanuela Greco Matteo Morandi Ivana Palucci Sabrina Mariotti Noemi Poerio Roberto Nisini Giovanni Delogu Maurizio Fraziano 《PloS one》2015,10(5)
A safer and more effective anti-Tuberculosis vaccine is still an urgent need. We probed the effects of monosodium urate crystals (MSU) on innate immunity to improve the Bacille Calmette-Guerin (BCG) vaccination. Results showed that in vitro MSU cause an enduring macrophage stimulation of the anti-mycobacterial response, measured as intracellular killing, ROS production and phagolysosome maturation. The contribution of MSU to anti-mycobacterial activity was also shown in vivo. Mice vaccinated in the presence of MSU showed a lower number of BCG in lymph nodes draining the vaccine inoculation site, in comparison to mice vaccinated without MSU. Lastly, we showed that MSU improved the efficacy of BCG vaccination in mice infected with Mycobacterium tuberculosis (MTB), measured in terms of lung and spleen MTB burden. These results demonstrate that the use of MSU as adjuvant may represent a novel strategy to enhance the efficacy of BCG vaccination. 相似文献
135.
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136.
Iva Bozic Danijela Savic Danijela Laketa Ivana Bjelobaba Ivan Milenkovic Sanja Pekovic Nadezda Nedeljkovic Irena Lavrnja 《PloS one》2015,10(2)
Microglial cells are resident immune cells of the central nervous system (CNS), recognized as key elements in the regulation of neural homeostasis and the response to injury and repair. As excessive activation of microglia may lead to neurodegeneration, therapeutic strategies targeting its inhibition were shown to improve treatment of most neurodegenerative diseases. Benfotiamine is a synthetic vitamin B1 (thiamine) derivate exerting potentially anti-inflammatory effects. Despite the encouraging results regarding benfotiamine potential to alleviate diabetic microangiopathy, neuropathy and other oxidative stress-induced pathological conditions, its activities and cellular mechanisms during microglial activation have yet to be elucidated. In the present study, the anti-inflammatory effects of benfotiamine were investigated in lipopolysaccharide (LPS)-stimulated murine BV-2 microglia. We determined that benfotiamine remodels activated microglia to acquire the shape that is characteristic of non-stimulated BV-2 cells. In addition, benfotiamine significantly decreased production of pro-inflammatory mediators such as inducible form of nitric oxide synthase (iNOS) and NO; cyclooxygenase-2 (COX-2), heat-shock protein 70 (Hsp70), tumor necrosis factor alpha α (TNF-α), interleukin-6 (IL-6), whereas it increased anti-inflammatory interleukin-10 (IL-10) production in LPS stimulated BV-2 microglia. Moreover, benfotiamine suppressed the phosphorylation of extracellular signal-regulated kinases 1/2 (ERK1/2), c-Jun N-terminal kinases (JNK) and protein kinase B Akt/PKB. Treatment with specific inhibitors revealed that benfotiamine-mediated suppression of NO production was via JNK1/2 and Akt pathway, while the cytokine suppression includes ERK1/2, JNK1/2 and Akt pathways. Finally, the potentially protective effect is mediated by the suppression of translocation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in the nucleus. Therefore, benfotiamine may have therapeutic potential for neurodegenerative diseases by inhibiting inflammatory mediators and enhancing anti-inflammatory factor production in activated microglia. 相似文献
137.
Katja Petzold Diane Poster Fabienne Krauer Katharina Spanaus Gustav Andreisek Thi Dan Linh Nguyen-Kim Ivana Pavik Thien Anh Ho Andreas L. Serra Laura Rotar 《PloS one》2015,10(4)
Background
Autosomal dominant polycystic kidney disease (ADPKD) is characterized by a decline in renal function at late disease stage when the majority of functional renal parenchyma is replaced by cystic tissue. Thus, kidney function, assessed by estimated glomerular filtration rate (eGFR) does not well represent disease burden in early disease. Here, we investigated various urinary markers for tubular injury and their association with disease burden in ADPKD patients at early disease course.Methods
ADPKD patients between 18 and 40 years with an eGFR greater or equal to 70 ml per min per 1.73m2 were eligible for this cross-sectional study. Urinary Neutrophil Gelatinase-Associated Lipocalin (NGAL), Kidney Injury Molecule-1 (KIM-1), and Uromodulin (UMOD) were investigated by Enzyme-Linked Immunosorbent Assay. Clara Cell Protein 16 (CC16) was investigated by Latex Immuno Assay. Cryoscopy was performed to assess urine osmolality and Urinary Albumin-to-Creatinine Ratio (UACR) was calculated. The association and the predictive properties of the markers on eGFR and height adjusted total kidney volume (htTKV) was evaluated using multiple regression analysis, incorporating different control variables for adjustment. Internal bootstrapping validated the obtained results.Results
In 139 ADPKD patients (age 31 ±7 years, mean eGFR of 93 ± 19 ml per min per 1.73 m2) the total kidney volume was negatively correlated with eGFR and UMOD and positive associated with age, UACR, KIM-1 and urine osmolality after adjustment for possible confounders. Urine osmolality and htTKV were also associated with eGFR, whereas no association of CC16, NGAL and UMOD with eGFR or htTKV was found.Conclusion
UACR and urinary KIM-1 are independently associated with kidney size but not with renal function in our study population. Urine osmolality was associated with eGFR and kidney volume following adjustment for multiple confounders. Despite statistical significance, the clinical value of our results is not yet conceivable. Further studies are needed to evaluate the property of the aforementioned biomarkers to assess disease state at early ADPKD stage. 相似文献138.
Introduction
In adults, microalbuminuria indicates generalized endothelial dysfunction, and is an independent risk factor for cardiovascular and all cause mortality. Slovak adults present one of the highest cardiovascular mortality rates in Europe. Thus Slovak adolescents are on a high-risk to develop cardiovascular afflictions early, and screening for microalbuminuria might be useful in early assessment of their cardiovascular risk. We aimed to study the prevalence of microalbuminuria in Slovak adolescents, and the association of urinary albumin-to-creatinine ratio (ACR) to cardiovascular risk factors.Subjects and methods
Anthropometric data, blood pressure, blood count, glucose homeostasis, lipid profile, renal function, inflammatory status, concentrations of homocysteine and uric acid were determined and associated with ACR in 2 666 adolescents (49.4% boys, 51.6% girls) aged 14-to-20 years. Microalbuminuria was classified as ACR 2.5–25.0 mg/mmol in boys and 3.5–35.0 mg/mmol in girls.Results
Prevalence of microalbuminuria in both genders reached 3.3%, and did not differ significantly between lean and centrally obese subjects. Girls presented higher ACR than boys (normoalbuminuric: 0.6±0.5 mg/mmol vs. 0.5±0.4 mg/mmol, p>0.001; microalbuminuric: 9.3±7.3 mg/mmol vs. 5.0±3.8 mg/mmol; p>0.001). Microalbuminuric adolescents and those presenting normoalbuminuria within the upper ACR quartile were slimmer than their normoalbuminuric counterparts or adolescents with normoalbuminuria within the lower quartile, respectively. No association between microalbuminuria and cardiovascular risk markers was revealed.Conclusion
Results obtained in this study do not support our assumption that ACR associates with cardiometabolic risk factors in apparently healthy adolescents. Follow-up studies until adulthood are needed to estimate the potential cardiometabolic risk of apparently healthy microalbuminuric adolescents. 相似文献139.
140.
Mami Shiwa Masayasu Yoneda Shuhei Nakanishi Kenji Oki Kiminori Yamane Nobuoki Kohno 《PloS one》2015,10(3)