Efficacy of Two Caries Detector Dyes in the Diagnosis of Dental Caries

Objective: The aim of the present study was to evaluate the efficacy of two caries detector dyes in the diagnosis of dental caries.Materials and Methods: Twenty extracted human posterior teeth without pulpal exposure were sectioned mesiodistally through the center of the lesions using a water-cooled disk.The tooth halves were randomly divided into two groups and treated with Caries Detector (CD) and Caries Check (CC) detector dyes. Access cavities were prepared followed by caries removal and dye application. All cavities were arbitrarily divided into two right and left sections and excavation of the stained areas was performed on the left parts, while the right sections remained untouched. Bacterial penetration into dentinal tubules was evaluated using Gram-stained decalcified sections under light microscopy. Sensitivity and specificity of both dyes were calculated.Results: The sensitivity of CD and CC were 74% and 71%,respectively. The specificity obtained for both dyes was 100%.Conclusion: Considering the low sensitivity of the dyes evaluated in the present study, it seems that they may not be reliable when used as the sole diagnostic technique for detection of carious lesions in posterior teeth

Escape from Autologous Neutralizing Antibodies in Acute/Early Subtype C HIV-1 Infection Requires Multiple Pathways

One aim for an HIV vaccine is to elicit neutralizing antibodies (Nab) that can limit replication of genetically diverse viruses and prevent establishment of a new infection. Thus, identifying the strengths and weaknesses of Nab during the early stages of natural infection could prove useful in achieving this goal. Here we demonstrate that viral escape readily occurred despite the development of high titer autologous Nab in two subjects with acute/early subtype C infection. To provide a detailed portrayal of the escape pathways, Nab resistant variants identified at multiple time points were used to create a series of envelope (Env) glycoprotein chimeras and mutants within the background of a corresponding newly transmitted Env. In one subject, Nab escape was driven predominantly by changes in the region of gp120 that extends from the beginning of the V3 domain to the end of the V5 domain (V3V5). However, Nab escape pathways in this subject oscillated and at times required cooperation between V1V2 and the gp41 ectodomain. In the second subject, escape was driven by changes in V1V2. This V1V2-dependent escape pathway was retained over time, and its utility was reflected in the virus's ability to escape from two distinct monoclonal antibodies (Mabs) derived from this same patient via introduction of a single potential N-linked glycosylation site in V2. Spatial representation of the sequence changes in gp120 suggested that selective pressure acted upon the same regions of Env in these two subjects, even though the Env domains that drove escape were different. Together the findings argue that a single mutational pathway is not sufficient to confer escape in early subtype C HIV-1 infection, and support a model in which multiple strategies, including potential glycan shifts, direct alteration of an epitope sequence, and cooperative Env domain conformational masking, are used to evade neutralization

Structure Activity Relationship of Dendrimer Microbicides with Dual Action Antiviral Activity

Topical microbicides, used by women to prevent the transmission of HIV and other sexually transmitted infections are urgently required. Dendrimers are highly branched nanoparticles being developed as microbicides. However, the anti-HIV and HSV structure-activity relationship of dendrimers comprising benzyhydryl amide cores and lysine branches, and a comprehensive analysis of their broad-spectrum anti-HIV activity and mechanism of action have not been published.Dendrimers with optimized activity against HIV-1 and HSV-2 were identified with respect to the number of lysine branches (generations) and surface groups. Antiviral activity was determined in cell culture assays. Time-of-addition assays were performed to determine dendrimer mechanism of action. In vivo toxicity and HSV-2 inhibitory activity were evaluated in the mouse HSV-2 susceptibility model. Surface groups imparting the most potent inhibitory activity against HIV-1 and HSV-2 were naphthalene disulfonic acid (DNAA) and 3,5-disulfobenzoic acid exhibiting the greatest anionic charge and hydrophobicity of the seven surface groups tested. Their anti-HIV-1 activity did not appreciably increase beyond a second-generation dendrimer while dendrimers larger than two generations were required for potent anti-HSV-2 activity. Second (SPL7115) and fourth generation (SPL7013) DNAA dendrimers demonstrated broad-spectrum anti-HIV activity. However, SPL7013 was more active against HSV and blocking HIV-1 envelope mediated cell-to-cell fusion. SPL7013 and SPL7115 inhibited viral entry with similar potency against CXCR4-(X4) and CCR5-using (R5) HIV-1 strains. SPL7013 was not toxic and provided at least 12 h protection against HSV-2 in the mouse vagina.Dendrimers can be engineered with optimized potency against HIV and HSV representing a unique platform for the controlled synthesis of chemically defined multivalent agents as viral entry inhibitors. SPL7013 is formulated as VivaGel(R) and is currently in clinical development to provide protection against HIV and HSV. SPL7013 could also be combined with other microbicides

SKELETODENTAL CHANGES DURING THE PUBERTAL GROWTH SPURT IN CLASS II DIV I FEMALES: A LONGITUDINAL STUDY

This study aimed to determine the quantity and character of growth changes in the skeletodental complex of class II div I malocclusion during the pubertal growth spurt in females. Longitudinal hand-wrist radiographs were obtained from each subject and the onset anil end of the pubertal growth spurt was determined. Accordingly two lateral cephaliograms were taken, superimposed and analyzed. This sample consisted of 36 girls (18 class I ami 18 class II div I malocclusions), with no history of orthodontic treatment. Tl"e results indicate that true changes exist during the short period of pubertal growth spurt, which differ in amount ami direction, in various parts of the face am! cranium; also the pubertal growth spurt may have different effects on identical parameters, when compared between class I and class II div I subjects

The Par-3 NTD adopts a PB1-like structure required for Par-3 oligomerization and membrane localization

The evolutionarily conserved Par-3/Par-6/aPKC complex is essential for the establishment and maintenance of polarity of a wide range of cells. Both Par-3 and Par-6 are PDZ domain containing scaffold proteins capable of binding to polarity regulatory proteins. In addition to three PDZ domains, Par-3 also contains a conserved N-terminal oligomerization domain (NTD) that is essential for proper subapical membrane localization and consequently the functions of Par-3. The molecular basis of NTD-mediated Par-3 membrane localization is poorly understood. Here, we describe the structure of a monomeric form of the Par-3 NTD. Unexpectedly, the domain adopts a PB1-like fold with both type-I and type-II structural features. The Par-3 NTD oligomerizes into helical filaments via front-to-back interactions. We further demonstrate that the NTD-mediated membrane localization of Par-3 in MDCK cells is solely attributed to its oligomerization capacity. The data presented in this study suggest that the Par-3 NTD is likely to facilitate the assembly of higher-order Par-3/Par-6/aPKC complex with increased avidities in targeting the complex to the subapical membrane domain and in binding to other polarity-regulating proteins