Pro Libris: Lubuskie Pismo Literacko-Kulturalne, nr 3 (2009)

134 s. : il.

A proteomic approach to investigating gene cluster expression and secondary metabolite functionality in Aspergillus fumigatus.

A combined proteomics and metabolomics approach was utilised to advance the identification and characterisation of secondary metabolites in Aspergillus fumigatus. Here, implementation of a shotgun proteomic strategy led to the identification of non-redundant mycelial proteins (n = 414) from A. fumigatus including proteins typically under-represented in 2-D proteome maps: proteins with multiple transmembrane regions, hydrophobic proteins and proteins with extremes of molecular mass and pI. Indirect identification of secondary metabolite cluster expression was also achieved, with proteins (n = 18) from LaeA-regulated clusters detected, including GliT encoded within the gliotoxin biosynthetic cluster. Biochemical analysis then revealed that gliotoxin significantly attenuates H2O2-induced oxidative stress in A. fumigatus (p>0.0001), confirming observations from proteomics data. A complementary 2-D/LC-MS/MS approach further elucidated significantly increased abundance (p<0.05) of proliferating cell nuclear antigen (PCNA), NADH-quinone oxidoreductase and the gliotoxin oxidoreductase GliT, along with significantly attenuated abundance (p<0.05) of a heat shock protein, an oxidative stress protein and an autolysis-associated chitinase, when gliotoxin and H2O2 were present, compared to H2O2 alone. Moreover, gliotoxin exposure significantly reduced the abundance of selected proteins (p<0.05) involved in de novo purine biosynthesis. Significantly elevated abundance (p<0.05) of a key enzyme, xanthine-guanine phosphoribosyl transferase Xpt1, utilised in purine salvage, was observed in the presence of H2O2 and gliotoxin. This work provides new insights into the A. fumigatus proteome and experimental strategies, plus mechanistic data pertaining to gliotoxin functionality in the organism

Strains of all-FRP composite bridge measured by the different methods

Konstrukcje mostowe zbudowane z kompozytów FRP charakteryzują się bardzo małym ciężarem zapewniającym łatwy transport i szybki montaż, możliwościami prefabrykacji całych przęseł, bardzo dużą wytrzymałością, doskonałą trwałością, odpowiednią sztywnością i dobrymi parametrami dynamicznymi. W referacie przedstawiono wyniki pomiarów odkształceń belkowego przęsła mostu typu all-composite. Pomiary odkształceń pod obciążeniem statycznym wykonano trzema różnymi metodami: metodą konwencjonalnej tensometrii elektrooporowej oraz za pomocą technologii strunowej i za pomocą rozłożonych czujników światłowodowe DFOS (ang. distributed fibre optic sensors). Przeprowadzone badania wykazały bardzo dużą zgodność odkształceń pomierzonych tymi metodami. Porównanie trzech technologii pomiarowych pozwoliło także na wybór technologii najbardziej odpowiedniej dla mostów kompozytowych.The all-composite bridges in which both the girder and deck slab are fully made of FRP composite, are characterized by: a very low weight, prefabrication even entire spans, very high strength, excellent durability, appropriate stiffness, and proper dynamic behavior of the bridge. The mail results of strain measurement in the all-composite bridge span under static load test have been presented. Three different measurement methods have been applied: vibrating strain gauge, distributed fibre optic sensors (DFOS) and strain gauge transducer. The proof load tests have revealed the good agreement and consistency between these results. The comparison made on the basis of measurements has allowed to choose the most appropriate method to be used in the further monitoring system of the bridge

The effect of tetramethylthiourea on the Zn2+\text{}^{2+} ions electroreduction in the presence of different detergents

The effect of the mixed adsorption layers: tetramethylthiourea and chosen detergent on the Zn$\text{}^{2+}$ ions electroreduction is described. The detergents concentration was 7.5·10$\text{}^{-4}$ M, which was lower of its critical micellation point. Three detergents: cationic, neutral and anionic were chosen for this study. First two detergents inhibited the Zn$\text{}^{2+}$ ions reduction at mercury electrode, the last detergent accelerated this process. Tetramethylthiourea eliminated the inhibiting effect of the detergent and accelerated the studied process stronger than in the detergents absence. Standard rate constants of Zn$\text{}^{2+}$ ions electroreduction were determined by cyclic voltammetry and impedance measurement

Supplementary Material for: CXCL12 in Patients with Chronic Kidney Disease and Healthy Controls: Relationships to Ambulatory 24-Hour Blood Pressure and Echocardiographic Measures

<b><i>Background/Aims:</i></b> Chronic kidney disease is a pro-inflammatory condition where the interplay between different regulatory pathways and immune cells mediates an unfavorable remodeling of the vascular wall and myocardial hypertrophy. These mechanisms include the action of CXCL12. The aim of this study is to evaluate the association between serum CXCL12 with left ventricular hypertrophy (LVH) and blood pressure control in chronic kidney disease (CKD) patients. <b><i>Methods:</i></b> This single-center observational study involved 90 stable CKD stage 1–5 patients (including 33 renal transplant recipients) and 25 healthy age- and sex-matched control subjects. CXCL12 was quantified by ELISA. 24-h ambulatory blood pressure monitoring was performed in 90 patients and 25 healthy controls. Left ventricular mass index (LVMI) was calculated based on the transthoracic echocardiography measurements in 27 patients out of the CKD population and in the whole control group. <b><i>Results:</i></b> CXCL12 correlated significantly with LVMI by multivariate regression analysis (coefficient <i>B</i> = 0.33, <i>p</i> = 0.02) together with age (<i>B</i> = 0.30, <i>p</i> = 0.03) and gender (<i>B</i> = 0.41, <i>p</i> = 0.003). A positive correlation was observed between CXCL12 and average 24-h systolic blood pressure (SBP) (rho = 0.35, <i>p</i> = 0.001), daytime SBP (rho = 0.35, <i>p</i> = 0.001), and nocturnal SBP (rho = 0.30, <i>p</i> = 0.002). Nocturnal hypertension was frequent (46% of CKD patients). <b><i>Conclusions:</i></b> The results of our study point towards a link between CXCL12 and LVH as well as blood pressure control among patients with CKD, supporting the thesis that CXCL12 may be regarded as a new potential uremic toxin