p53 codon 72 polymorphism is associated with susceptibility to hepatocellular carcinoma in the Turkish population: a case–control study

The tumor suppressor p53 gene plays a crucial role in preventing carcinogenesis through its ability to induce cell cycle arrest and apoptosis following DNA damage and oncogene activation. A guanine (G)/cytosine (C) common single nucleotide polymorphism (SNP) at second position of codon 72 in exon 4 of p53 gene determines a arginine (Arg) to proline (Pro) (Arg72Pro) aminoacidic substitution within the proline-rich domain of p53 protein. Arg72 and Pro72 allele are different from a biochemical and biological point of view and many reports suggest that they can modulate individual cancer susceptibility. To determine the association of the p53 Arg72Pro polymorphism with the risk of hepatocellular carcinoma (HCC) development in a Turkish population, a hospital-based case–control study was designed consisting of 119 subjects with HCC and 119 cancer-free control subjects matched for age, gender, smoking and alcohol status. The genotype frequency of the p53 Arg72Pro polymorphism was determined by using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Our data shows that the Pro/Pro genotype of the p53 Arg72Pro polymorphism is associated with increased risk of HCC development in this Turkish population (OR = 3.20, 95% CI: 1.24–8.22, P = 0.02). Furthermore, according to stratified analysis, a significant association was observed between the homozygote Pro/Pro genotype and HCC risk in the subgroups of male gender (OR = 3.01, 95% CI: 1.14–7.97, P = 0.03) and patients with hepatitis B virus (HBV)-related HCC (OR = 4.04, 95% CI: 1.46–11.15, P = 0.007). Because our results suggest for the first time that the Pro/Pro homozygote of p53 Arg72Pro polymorphism may be a genetic susceptibility factor for HCC (especially in the male gender and HBV-infected patients) in the Turkish population, further independent studies are required to validate our findings in a larger series, as well as in patients of different ethnic origins.     

Beta-lactams resistance and presence of class 1 integron in Pseudomonas spp. isolated from untreated hospital effluents in Brazil

The aim of the present study was to investigate the resistance profile, to detect the presence of beta-lactam resistance genes, phenotypic expression of efflux pump systems and class 1 integrons in Pseudomonas spp. strains obtained from untreated hospital effluents. Effluent samples were collected from four hospitals in Porto Alegre, RS, Brazil. Pseudomonas were isolated on MacConkey agar plates and the identification was confirmed by 16S rRNA PCR and biochemical tests. Susceptibility testing was determined by disk-diffusion method using 11 different beta-lactams and MIC assays were performed on isolates resistant to imipenem and ceftazidime. The beta-lactamase genes bla _IMP, bla _VIM, bla _SPM-1, bla _OXA-23-like, bla _OXA-24-like, bla _OXA-51-like and the intl1 gene from class 1 integron were analysed by PCR. One hundred and twenty-four isolates were recovered and the most common species was Pseudomonas pseudoalcaligenes. The resistance found among the isolates was considered high, 62 (50%) isolates were multiresistant. No isolate carrying the beta-lactamase genes tested was found among the strains. Seven isolates showed reduction of MIC for imipenem and ceftazidime in the presence of cyanide m-chlorophenylhydrazone, indicating the hyper expression of efflux pumps. From the 124 isolates, 52 (41.9%) were identified as carrying the class 1 integron gene, intI1. Untreated hospital effluents could be a source of environmental contamination due to discharge of antimicrobial resistant bacteria which can carry integron class 1 and act as a reservoir of resistance genes and have efflux pump systems.     

Amoebal host range, host-free survival and disinfection susceptibility of environmental Chlamydiae as compared to Chlamydia trachomatis

The term 'Chlamydia-like organisms' encompasses obligate intracellular bacterial species phylogenetically close to Chlamydiaceae. Most are associated with free-living amoebae, and several could be responsible for respiratory tract infections and abortion in human and animals. Despite increasing concern about their pathogenic role, the prevalence, biodiversity and ecology of Chlamydia-related bacteria still remain largely unknown. In this study, six members of the Chlamydiales were tested, including Parachlamydia acanthamoebae (two different strains), Protochlamydia naegleriophila, Waddlia chondrophila, Criblamydia sequanensis and Chlamydia trachomatis as a reference. Intracellular growth was tested in 11 different Acanthamoeba strains, demonstrating significant differences in host susceptibilities to infection depending on strains investigated. Survival of host-free bacteria in suspension or dried onto surfaces was also explored, demonstrating that Chlamydia-like organisms present better survival capacity than C. trachomatis. Longer survival times were observed for bacteria suspended in rich culture medium, with survivors being detected after 10 weeks incubation. We also tested susceptibility of host-free Chlamydia-like organisms to several disinfection treatments. Each chemical biocide tested reduced viability of host-free Chlamydia by more than 4 logs. Conversely, all Chlamydia-like organisms tested resisted exposure at 55 °C for 10 min, while C. trachomatis was completely inactivated.     

Study on the influence of cranberry extract ?uravit S·O·S(?) on the properties of uropathogenic Escherichia coli strains, their ability to form biofilm and its antioxidant properties

Consumption of cranberries is known to exert positive health effects, especially against urinary tract infections. For this reason, presumably, they are widely used in folk medicine. Different aspects of cranberry phenolics activity were studied in individual papers but complex study in this matter is missing. The aim of the present study is to provide complex data concerning various aspects of cranberry extract activity. We studied the effects of subinhibitory concentrations of commercially available extract (?uravit S·O·S(?)) against two Escherichia coli strains isolated from urine of patients with pyelonephritis. Additionally the main extract anthocyanins were characterized. The activity of extract against lipid peroxidation and its radical scavenging ability were also assessed. ?uravit S·O·S(?) decreased the hydrophobicity of one of the studied E. coli strains, reduced swimming motility and adhesion to epithelial cells of both studied strains, it also limited the ability of bacteria to form biofilm. Expression of curli was not affected by cranberry extract, the assessment of P fimbriae expression was not reliable due to extract-induced agglutination of erythrocytes. Cranberry extract caused filamentation in both studied E. coli strains. It also showed pronounced antioxidant and radical scavenging properties. The properties of the studied cranberry extract show that it could be effectively used in prevention and/or elimination of urinary tract infections, specially the recurrent ones.     

Circadian rhythm-dependent alterations of gene expression in Drosophila brain lacking fragile X mental retardation protein

Fragile X syndrome is caused by the loss of the FMR1 gene product, fragile X mental retardation protein (FMRP). The loss of FMRP leads to altered circadian rhythm behaviors in both mouse and Drosophila; however, the molecular mechanism behind this phenomenon remains elusive. Here we performed a series of gene expression analyses, including of both mRNAs and microRNAs (miRNAs), and identified a number of mRNAs and miRNAs (miRNA-1 and miRNA-281) with circadian rhythm-dependent altered expression in dfmr1 mutant flies. Identification of these RNAs lays the foundation for future investigations of the molecular pathway(s) underlying the altered circadian rhythms associated with loss of dFmr1.     

Canine Recombinant Adenovirus Vector Induces an Immunogenicity-Related Gene Expression Profile in Skin-Migrated CD11b+ -Type DCs

Gene expression profiling of the blood cell response induced early after vaccination has previously been demonstrated to predict the immunogenicity of vaccines. In this study, we evaluated whether the analysis of the gene expression profile of skin-migrated dendritic cells (DCs) could be informative for the in vitro prediction of immunogenicity of vaccine, using canine adenovirus serotype 2 (CAV2) as vaccine vector. CAV2 has been shown to induce immunity to transgenes in several species including sheep and is an interesting alternative to human adenovirus-based vectors, based on the safety records of the parental strain in dogs and the lack of pre-existing immunity in non-host species. Skin-migrated DCs were collected from pseudo-afferent lymph in sheep. Both the CD11b⁺ -type and CD103⁺ -type skin-migrated DCs were transduced by CAV2. An analysis of the global gene response to CAV2 in the two skin DC subsets showed that the gene response in CD11b⁺ -type DCs was far higher and broader than in the CD103⁺ -type DCs. A newly released integrative analytic tool from Ingenuity systems revealed that the CAV2-modulated genes in the CD11b⁺ -type DCs clustered in several activated immunogenicity-related functions, such as immune response, immune cell trafficking and inflammation. Thus gene profiling in skin-migrated DC in vitro indicates that the CD11b⁺ DC type is more responsive to CAV2 than the CD103⁺ DC type, and provides valuable information to help in evaluating and possibly improving viral vector vaccine effectiveness.     

Dietary Lysine Imbalance Affects Muscle Proteome in Zebrafish (Danio rerio): A Comparative 2D-DIGE Study

Lysine (Lys) is an indispensable amino acid (AA) and generally the first limiting AA in vegetable protein sources in fish feeds. Inadequate dietary Lys availability may limit protein synthesis, accretion and growth of fish. This experiment aimed to further elucidate the role of Lys imbalance on growth by examining the myotomal muscle proteome of juvenile zebrafish (Danio rerio). Quadruplicate groups of 8 fish were fed either a low-Lys [Lys(-), 1.34?g?kg(-1)], medium/control (Lys, 2.47?g?kg(-1)) or high-Lys [Lys(+), 4.63?g?kg(-1)] diet. Fish growth was monitored from 33 to 49?days post-fertilization (dpf) and trunk myotomal muscle proteome of Lys(-) and Lys(+) treatments were screened by 2D-DIGE and MALDI ToF tandem mass spectrometry. Growth rate was negatively affected by diet Lys(-). Out of 527?±?11 (mean?±?S.E.M.) protein spots detected (～10-150?kDa and 4-7 pI value), 30 were over-expressed and 22 under-expressed in Lys(-) fish (|fold-change| >1.2, p value <0.05). Higher myosin light chains abundance and other myofibrillar proteins in Lys(-) fish pointed to increased sarcomeric degradation, indicating a higher protein turnover for supplying basal energy-saving metabolism rather than growth and muscle protein accretion. The Lys deficiency also possibly induced a higher feeding activity, reflected in the over-expression of beta enolase and mitochondrial ATP synthase. Contrarily, in the faster growing fish [Lys(+)], over-expression of apolipoprotein A-I, F-actin capping protein and Pdlim7 point to increased energy storage as fat and enhanced muscle growth, particularly by mosaic hyperplasia. Thus using an exploratory approach, this study pinpoints interesting candidates for further elucidating the role of dietary Lys on growth of juvenile fish.     

Estimation of 3D shape, internal density and mechanics of proximal femur by combining bone mineral density images with shape and density templates

Measurement of bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA) alone is only a moderate predictor of fracture risk. Finite element analysis (FEA) of bone mechanics, based on DXA images, may improve the prediction of fracture risk. We developed a method to estimate the 3D shape and density distribution of the proximal femur, using a 2D BMD image and a femur shape template. Proximal femurs of eighteen human cadavers were imaged using computed tomography and divided into two sets (N = 9 + 9). The template was created from the samples in first set by using 3D generalized Procrustes analysis and thin-plate splines. Subsequently, the template and 2D BMD image were utilized to estimate the shape and internal density distribution of the femurs in the second set. Finally, FEA was conducted based on the original and the estimated bone models to evaluate the effect of geometrical and density distributional errors on the mechanical strength. The volumetric errors induced by the estimation itself were low (<1.4%). In the estimation of bones in the second set, the mean distance difference between the estimated and the original bone surfaces was 0.80 ± 0.19 mm, suggesting feasible estimation of the femoral shape. The mean absolute error in voxel-by-voxel BMD was 120±8 mg cm?3. In FEA, the stiffness of the proximal femur differed by -7±16% between the original and estimated bones. The present method, in comparison with methods used in previous studies, improved the prediction of the geometry, the BMD distribution and the mechanical characteristics of the proximal femur. Potentially, the proposed method could ultimately improve the determination of bone fracture risk.