Oxidative stress in subjects affected by celiac disease

In order to study the role of oxidative stress in celiac disease, protein carbonyl groups, thiobarbituric acid-reactive substance and pentosidine were evaluated in the plasma of nine patients with asymptomatic celiac disease and in a control group (n = 25). Plasma alpha-tocopherol, retinol and lipids were determined in the same samples. The levels of markers of oxidative stress derived from both protein (carbonyl groups) and lipids (thiobarbituric acid-reactive substances) were significantly higher in celiac disease patients, whereas lipoproteins and alpha-tocopherol were significantly lower. These data indicate that in celiac disease, even when asymptomatic, a redox imbalance persists; this is probably caused by an absorption deficiency, even if slight. Dietary supplementation with antioxidant molecules may offer some benefit and deserves further investigation.     

Bacterial community structure of a lab‐scale anammox membrane bioreactor

Autotrophic nitrogen removal technologies have proliferated through the last decade. Among these, a promising one is the membrane bioreactor (MBR) Anammox, which can achieve very high solids retention time and therefore sets a proper environment for the cultivation of anammox bacteria. In this sense, the MBR Anammox is an efficient technology for the treatment of effluents with low organic carbon and high ammonium concentrations once it has been treated under partial nitrification systems. A lab‐scale MBR Anammox bioreactor has been built at the Technological University of Delft, The Netherlands and has been proven for efficient nitrogen removal and efficient cultivation of anammox bacteria. In this study, next‐generation sequencing techniques have been used for the investigation of the bacterial communities of this MBR Anammox for the first time ever. A strong domination of Candidatus Brocadia bacterium and also the presence of a myriad of other microorganisms that have adapted to this environment were detected, suggesting that the MBR Anammox bioreactor might have a more complex microbial ecosystem that it has been thought. Among these, nitrate‐reducing heterotrophs and primary producers, among others, were identified. Definition of the ecological roles of the OTUs identified through metagenomic analysis was discussed. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 31:186–193, 2015     

Critical temperatures for xylogenesis in conifers of cold climates

Aim To identify temperatures at which cell division and differentiation are active in order to verify the existence of a common critical temperature determining growth in conifers of cold climates. Location Ten European and Canadian sites at different latitudes and altitudes. Methods The periods of cambial activity and cell differentiation were assessed on a weekly time‐scale on histological sections of cambium and wood tissue collected over 2 to 5 years per site from 1998 to 2005 from the stems of seven conifer species. All data were compared with daily air temperatures recorded from weather stations located close to the sites. Logistic regressions were used to calculate the probability of xylogenesis and of cambium being active at a given temperature. Results Xylogenesis lasted from May to October, with a growing period varying from 3 to 5 months depending on location and elevation. Despite the wide geographical range of the monitored sites, temperatures for onset and ending of xylogenesis converged towards narrow ranges with average values around 4–5, 8–9 and 13–14 °C for daily minimum, mean and maximum temperature, respectively. On the contrary, cell division in the cambium stopped in July?August, when temperatures were still high. Main conclusions Wood formation in conifers occurred when specific critical temperatures were reached. Although the timing and duration of xylogenesis varied among species, sites and years, the estimated temperatures were stable for all trees studied. These results provide biologically based evidence that temperature is a critical factor limiting production and differentiation of xylem cells in cold climates. Although daily temperatures below 4?5 °C are still favourable for photosynthesis, thermal conditions below these values could inhibit the allocation of assimilated carbon to structural investment, i.e. xylem growth.     

High Prevalence of Nickel Allergy in an Overweight Female Population: A Pilot Observational Analysis

Context

In our Allergy Unit, we incidentally observed that a low Nickel diet, prescribed for delayed allergy to Nickel sulfate, reduced body mass index (BMI) and waist circumference in overweight patients.

Objectives

This pilot cross-sectional analysis was undertaken to compare the prevalence of Nickel allergy of overweight individuals versus the general population. We also had the chance to report the efficacy of a low Nickel diet on BMI and waist circumference in Nickel-sensitive overweight subjects.

Methods

Eighty-seven overweight subjects, with a BMI >26 Kg/m², were consecutively enrolled in a health prevention program, and screened for the presence of Nickel allergy. The enrolled population was mostly females (72/87) (82.8%). Forty-three overweight women and two men showed a Nickel allergy and started a low Nickel diet. After 6-months of dieting, 24 overweight allergic women could be traced and changes in BMI and waist circumference were calculated.

Main Outcome Measurements

Prevalence of Nickel allergy in overweight.

Results

Prevalence of Nickel allergy in overweight female was 59.7%, compared with a prevalence rate of 12.5% in the general population. A significant reduction in BMI was observed in 24 out of 43 overweight females with Nickel allergy after 24 weeks of a low Nickel diet. Relative to baseline, mean BMI decrease was 4.2±0.5 (P <0.001) and the mean decline in waist circumference was 11.7±0.6 cm (P< 0.001).

Conclusions

This pilot observational analysis showed a substantially higher prevalence of Nickel allergy among overweight females, especially those with metabolic syndrome and fatty liver disease. A normocaloric low Nickel diet was effective in reducing BMI in this population. Further research is strongly needed to confirm these preliminary findings.     

Fine spatial assembly for construction of the phenol-binding pocket to capture bisphenol A in the human nuclear receptor estrogen-related receptor γ

Various lines of evidence have shown that bisphenol A (BPA) acts as an endocrine disruptor that affects various hormones even at merely physiological levels. We demonstrated recently that BPA binds strongly to human nuclear receptor estrogen-related receptor γ (ERRγ), one of 48 nuclear receptors. Based on X-ray crystal analysis of the ERRγ ligand-binding domain (LBD)/BPA complex, we demonstrated that ERRγ receptor residues, Glu275 and Arg316, function as the intrinsic-binding site of the phenol-hydroxyl group of BPA. If these phenol-hydroxyl?Glu275 and Arg316 hydrogen bonds anchor the A-benzene ring of BPA, the benzene-phenyl group of BPA would be in a pocket constructed by specific amino acid side chain structures. In the present study, by evaluating the Ala-replaced mutant receptors, we identified such a ligand-binding pocket. Leu268, Leu271, Leu309 and Tyr326, in addition to the previously reported participants Glu275 and Arg316, were found to make a receptacle pocket for the A-ring, whereas Ile279, Ile310 and Val313 were found to assist or structurally support these residues. The results revealed that each amino acid residue is an essential structural element for the strong binding of BPA to ERRγ.     

Evidence for the presence of photorespiration in desiccation-sensitive leaves of the C4 'resurrection' plant Sporobolus stapfianus during dehydration stress

The possible role of photorespiration as a general stress protectionmechanism, and in C₄ plant metabolism, is controversial. Inparticular, the potential involvement of photorespiration inthe acquisition of desiccation tolerance in ‘resurrection’plants is unknown. An investigation was carried out into whetherphotorespiration is present in leaves of the C₄ resurrectionplant Sporobolus stapfianus Gandoger (Poaceae) and whether itfunctions as a mechanism of stress resistance in the desiccation-tolerantyounger leaves (YL) of this plant. It is shown that the enzymesinvolved in the photorespiratory pathway maintain their activityuntil 88% relative water content (RWC) in both YL and desiccation-sensitiveolder leaves (OL). In subsequent stages of dehydration stress,the enzymatic activity declined similarly in both YL and OL.The content of the phorespiratory metabolite, serine, and ethanolamine,a direct product of serine decarboxylation, is higher in theearly stages of dehydration (88% RWC) in OL, suggesting a transientlyenhanced photorespiratory activity in these leaves. This wasconfirmed by simultaneous gas exchange and fluorescence measurements,showing suppression of the electron transport rate in OL exposedto non-photorespiratory conditions (2% O₂) at 85% RWC. It isconcluded that a higher photorespiratory electron transportoccurs in desiccation-sensitive OL, and it is therefore proposedthat the capacity to scavenge excess electrons through photorespirationdoes not contribute to protect leaves of the desiccation-tolerantYL of S. stapfianus during the stress. Key words: Ethanolamine, glycine, photorespiratory enzymes, photosynthesis, poikilohydric plant, serine Received 5 June 2007; Revised 3 September 2007 Accepted 17 September 2007     

Epidemiological features and resistance pattern in uropathogens isolated from chronic bacterial prostatitis

Chronic bacterial prostatitis (CBP) is, usually, caused by uropathogens, especially gram-negative bacilli, although infection is sometimes due to Gram-positive and atypical microorganisms. A recent increasing in prevalence of Gram-positive strains has been reported. The aim of this study was to explore the epidemiological features and resistance rates in uropathogens isolated from CBP outpatients in last 10 years. All consecutive outpatients with demonstrated CBP attending a single Sexually Transmitted Disease centre from January 1997 and December 2008, were enrolled and underwent microbiological cultures in first void early morning urine, midstream urine, expressed prostatic secretion, and post prostate massage urine. Prevalence of different bacterial strains was stratified in four different periods: 1997–1999, 2000–2002, 2003–2005, 2006–2008. Any changes observed in epidemiological features and resistance rates in uropathogens over the whole study period have been analyzed. The present study has been planned, thus, as in vitro study. From 6,221 patients, 4,601 Gram-positive and 1,620 Gram-negative bacterial strains have been isolated. Enterococcus faecalis and Escherichia coli strains are the first and second frequent pathogens found, respectively. Significant differences between E. faecalis prevalence in the 1997–1999 and 2006–2008 periods were found. E. coli showed a significant difference between prevalence in 1997–1999 and 2006–2008 periods. Gram-positive organisms showed a decreasing of susceptibility to ciprofloxacin as well as Gram-negative strains, while a good susceptibility to the levofloxacin was evidenced. E. faecalis prevalence seemed to be raised in 2006–2008 periods. Moreover, a decreasing of activity of ciprofloxacin and a good activity profile of levofloxacin have been reported.     

Measurement of warfarin in the oral fluid of patients undergoing anticoagulant oral therapy

Background

Patients on warfarin therapy undergo invasive and expensive checks for the coagulability of their blood. No information on coagulation levels is currently available between two controls.

Methodology

A method was developed to determine warfarin in oral fluid by HPLC and fluorimetric detection. The chromatographic separation was performed at room temperature on a C-18 reversed-phase column, 65% PBS and 35% methanol mobile phase, flow rate 0.7 mL/min, injection volume 25 µL, excitation wavelength 310 nm, emission wavelength 400 nm.

Findings

The method was free from interference and matrix effect, linear in the range 0.2–100 ng/mL, with a detection limit of 0.2 ng/mL. Its coefficient of variation was <3% for intra-day measurements and <5% for inter-day measurements. The average concentration of warfarin in the oral fluid of 50 patients was 2.5±1.6 ng/mL (range 0.8–7.6 ng/mL). Dosage was not correlated to INR (r = −0.03, p = 0.85) but positively correlated to warfarin concentration in the oral fluid (r = 0.39, p = 0.006). The correlation between warfarin concentration and pH in the oral fluid (r = 0.37, p = 0.009) confirmed the importance of pH in regulating the drug transfer from blood. A correlation between warfarin concentration in the oral fluid and INR was only found in samples with pH values ≥7.2 (r = 0.84, p = 0.004).

Conclusions

Warfarin diffuses from blood to oral fluid. The method allows to measure its concentration in this matrix and to analyze correlations with INR and other parameters.     

Affinity analysis of differentially expressed genes in hepatocytes expressing HCV core genotype 1b or 3a

Chronic hepatitis C patients display many genotype-specific clinical features of HCV infection. The core proteins encoded by different genotypes dysregulate numerous sets of distinct host genes. In this study we tested the hypothesis that HCV core proteins 1b and 3a would actually act on a limited number of independent cellular players, as well as on several functionally linked gene products. Structural and functional tests identified a core set of host genes dysregulated by HCV core genotypes 1b and 3a. The core proteins of HCV genotypes 1b and 3a target specifically limited sets of functionally related gene products, which may be responsible for the variations in the clinical spectra associated with HCV infection.