Comparison of the Bacterial Composition and Structure in Symptomatic and Asymptomatic Endodontic Infections Associated with Root-Filled Teeth Using Pyrosequencing

Residual microorganisms and/or re-infections are a major cause for root canal therapy failure. Understanding of the bacterial content could improve treatment protocols. Fifty samples from 25 symptomatic and 25 asymptomatic previously root-filled teeth were collected from Sudanese patients with periradicular lesions. Amplified 16S rRNA gene (V1-V2) variable regions were subjected to pyrosequencing (FLX 454) to determine the bacterial profile. Obtained quality-controlled sequences from forty samples were classified into 741 operational taxonomic units (OTUs) at 3% dissimilarity, 525 at 5% dissimilarity and 297 at 10% dissimilarity, approximately corresponding to species-, genus- and class levels. The most abundant phyla were: Firmicutes (29.9%), Proteobacteria (26.1%), Actinobacteria (22.72%), Bacteroidetes (13.31%) and Fusobacteria (4.55%). Symptomatic patients had more Firmicutes and Fusobacteria than asymptomatic patients, while asymptomatic patients showed more Proteobacteria and Actinobacteria. Interaction of disease status and age was observed by two-way ANOSIM. Canonical correspondence analysis for age, tooth restoration and disease status showed a correlation of disease status with the composition and prevalence of different members of the microbial community. The pyrosequencing analysis revealed a distinctly higher diversity of the microbiota compared to earlier reports. The comparison of symptomatic and asymptomatic patients showed a clear association of the composition of the bacterial community with the presence and absence of symptoms in conjunction with the patients’ age.     

Distribution of HSV-1 IgG antibodies by two methods comparing in Turkish atopic children

Herpes Simplex Virus Type 1 (HSV-1) is a ubiquitous pathogen. Other than known diseases, HSV-1 may have an important role in the pathogenesis of atopy by causing immortality of th2 cells. From June 1st to July 31st 2006, seventy five blood samples were collected from atopic children referred to the allergy clinic of the hospital. The bloods samples were used to detect HSV-1 IgG antibodies by Enzyme-Linked Immunosorbent Assay and Virus Neutralization Test. HSV-1 IgG antibody seroprevalence in atopic children was found high, 62.6% by Enzyme-Linked Immunosorbent Assay and 57.3% by Virus Neutralization Test. Thus Virus Neutralization Test sensitivity was 92.15% and specificity was 100% regarding to the Enzyme-Linked Immunosorbent Assay technic. Although Enzyme-Linked Immunosorbent Assay was more sensitive than Virus Neutralization Test, there was no significant difference between two technics (p > 0.05) in detecting HSV-1 IgG antibodies in serum.     

PAK4, a novel effector for Cdc42Hs, is implicated in the reorganization of the actin cytoskeleton and in the formation of filopodia.

The GTPases Rac and Cdc42Hs control diverse cellular functions. In addition to being mediators of intracellular signaling cascades, they have important roles in cell morphogenesis and mitogenesis. We have identified a novel PAK-related kinase, PAK4, as a new effector molecule for Cdc42Hs. PAK4 interacts only with the activated form of Cdc42Hs through its GTPase-binding domain (GBD). Co-expression of PAK4 and the constitutively active Cdc42HsV12 causes the redistribution of PAK4 to the brefeldin A-sensitive compartment of the Golgi membrane and the subsequent induction of filopodia and actin polymerization. Importantly, the reorganization of the actin cytoskeleton is dependent on PAK4 kinase activity and on its interaction with Cdc42Hs. Thus, unlike other members of the PAK family, PAK4 provides a novel link between Cdc42Hs and the actin cytoskeleton. The cellular locations of PAK4 and Cdc42Hs suggest a role for the Golgi in cell morphogenesis.     

Mechanisms of giemsa banding of chromosomes. I. Giemsa-11 banding with azure and eosin.

Two components of Giemsa are necessary to obtain Giemsa-11 banding. These are an azure (either azure A or B) and eosin Y. The conditions under which azure and eosin interact to differentiate 9qh and other magenta-colored regions involve: (1) the absolute concentrations and ratio of the two dyes; (2) the pH and, to a lesser extent (3) the buffer composition of the staining solution. Differentiation is accompanied by the presence of magenta-colored precipitate, the formation of which is altered by any of the above-mentioned conditions. The absorption spectra of magentacolored and adjacent pale blue regions, measured in situ, show a significant change from those of dye mixtures and dye components in solution. These changes suggest the formation of an azure-eosinate complex. At neutral pH, differentiation of magenta-colored regions is not successful under conditions which denature DNA; e.g. (1) high temperatures; or (2) incubation in formamide. At alkaline pH (11.6), neither moderately high temperature nor fixation of chromosomes with formalin appears to affect Giemsa-11 banding. Thus, differential denaturation of DNA does not appear to play a key role.     

Effects of carbohydrate headgroups on the stability of induced cubic phases in binary mixtures of glycolipids

This paper is part in a series of papers, investigating the influence of carbohydrate headgroups on the mesogenic properties of glycolipids. While previous papers focussed on the synthesis and mesogenic properties of the pure compounds, we will discuss here our results obtained with binary mixtures. Mixtures of compounds, one forming a lamellar phase and the other one a columnar phase in their pure state, displayed always an induced cubic phase. The stability of this induced cubic phase depends significantly on the structure of the carbohydrate headgroup of both components. Thus it was possible to derive structure–property relationships by comparison of the phase diagrams that have been obtained, if the carbohydrate headgroup of one component was changed systematically. We observed an interesting effect of galactose headgroups which might be of great biological importance. Furthermore, the observed kind of kinetic of the S_A→cub transition might also be of great biological relevance.     

Association Studies of Calcium-Sensing Receptor (CaSR) Polymorphisms with Serum Concentrations of Glucose and Phosphate,and Vascular Calcification in Renal Transplant Recipients

Background

Cardiovascular disease is the major cause of death in renal transplant recipients (RTRs) and linked to arterial calcification. The calcium-sensing receptor (CaSR), a G-protein coupled receptor, plays a pivotal role in extracellular calcium homeostasis and is expressed in the intimal and medial layers of the arterial wall. We investigated whether common CASR gene variants are predictors for aortic and coronary artery calcification or influence risk factors such as serum calcium, phosphate and glucose concentrations in RTRs.

Methods

Two hundred and eighty four RTRs were investigated for associations between three CASR promoter region single nucleotide polymorphisms (SNPs) (rs115759455, rs7652589, rs1501899), three non-synonymous CASR coding region SNPs (A986S, R990G, Q1011E), and aortic and coronary artery calcium mass scores, cardiovascular outcomes and calcification risk factors that included serum phosphate, calcium, total cholesterol and glucose concentrations.

Results

Multivariate analysis revealed that RTRs homozygous for the minor allele (SS) of the A986S SNP, when compared to those homozygous for the major allele (AA), had raised serum glucose concentrations (8.7±5.4 vs. 5.7±2.1 mmol/L, P<0.05). In addition, RTRs who were heterozygous (CT) at the rs115759455 SNP, when compared to those homozygous for the major allele (CC), had higher serum phosphate concentrations (1.1±0.3 vs. 1.0±0.2 mmol/L, P<0.05). CASR SNPs were not significant determinants for aortic or coronary artery calcification, and were not associated with cardiovascular outcomes or mortality in this RTR cohort.

Conclusions

Common CASR SNPs may be independent predictors of serum glucose and phosphate concentrations, but are not determinants of vascular calcification or cardiovascular outcomes.