Effects on dentin nanomechanical properties, cell viability and dentin wettability of a novel plant-derived biomodification monomer.

Objectives: To evaluate the effects of dentin biomodification agents (Proanthocyanidin (PAC), Cardol (CD) and Cardol-methacrylate (CDMA) on dentin hydrophilicity by contact angle measurement, viability of dental pulp stem cells (DPSCs) and nanomechanical properties of the hybrid layer (HL).

Methods: CDMA monomer was synthesized from cardol through methacrylic acid esterification. Human extracted third molars were used for all experiments.

Volumetric polymerization shrinkage and its comparison to internal adaptation in bulk fill and conventional composites: A μCT and OCT in vitro analysis.

Objective: To quantify the volumetric polymerization shrinkage (VPS) of different conventional and bulk fill resin composites, through micro-computed tomography (μCT), and qualitative comparison of gap formation through optical coherence tomography (OCT).

Methods: Box-shaped class I cavities were prepared in 30 third-molars and divided into 5 groups (n=6): G1- Filtek Z100 (Z100); G2- Tetric Evoceram Bulk Fill (TEC); G3- Tetric EvoFlow Bulk fill (TEF); G4- Filtek Bulk fill (FBU); and G5- Filtek Bulk fill Flowable (FBF). All groups were treated with Adper Single Bond Plus adhesive and light cured (Bluephase 20i).

In vivo evaluation of resorbable supercritical CO -treated collagen membranes for class III furcation-guided tissue regeneration.

The study evaluated the effects of a Supercritical CO (scCO ) on a commercially available decellularized/delipidized naturally derived porcine pericardium collagen membrane, Vitala®. The Vitala® and scCO treated experimental membranes were evaluated for guided tissue regeneration (GTR) of periodontal tissue in class III furcation defects utilizing a dog model. Physical material characterization was performed by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC).

Assessment of cuspal deflection and volumetric shrinkage of different bulk fill composites using non-contact phase microscopy and micro-computed tomography.

The understanding of cuspal deflection and volumetric shrinkage of resin composites is necessary to assess and improve the placement techniques of resin-based materials. The aim of this study was to investigate the cuspal deflection and its relationship with volumetric polymerization shrinkage of different bulk-fill resin composites. The investigation was conducted using non-contact phase microscopy and micro-computed tomography.

Micro-computed tomography evaluation of volumetric polymerization shrinkage and degree of conversion of composites cured by various light power outputs.

This study evaluated the influence of different light-curing modes on the volumetric polymerization shrinkage and degree of conversion of a composite resin at different locations using micro-computed tomography and Fourier transform infrared spectroscopy (FTIR). Specimens were divided into 4 groups based on the light-curing mode used (Bluephase 20i): 1 -High (1,200 mW/cm); 2 -Low (650 mW/cm); 3 -Soft-start (650-1,200 mW/cm); and 4 -Turbo (2,000 mW/cm). Degree of conversion was calculated by the measurement of the peak absorbance height of the uncured and cured materials at the specific wavenumbers, and was performed by FTIR 48 h after curing resin samples.

Void and gap evaluation using microcomputed tomography of different fiber post cementation techniques.

Statement Of Problem: Few studies have investigated the voids and gaps produced during the cementation of fiber posts using different techniques.

Purpose: The purpose of this study was to evaluate and quantify void and gap area formations of different fiber post cementation techniques using microcomputed tomography (μCT).

Material And Methods: Standardized endodontically treated acrylic resin roots (N=24) were divided into 4 groups (n=6) according to different fiber posts cemented with the resin cement (FB); fiber posts relined with composite resin followed by cementation (FBR); fiber posts cemented using an ultrasonic device (FBU); and fiber posts relined with composite resin and cemented using an ultrasonic device (FBRU).

Volumetric shrinkage and film thickness of cementation materials for veneers: An in vitro 3D microcomputed tomography analysis.

Statement Of Problem: Few studies have investigated the volumetric polymerization shrinkage and film thickness of the different cementation techniques used to cement veneers.

Purpose: The purpose of this in vitro study was to evaluate the volumetric polymerization shrinkage (VS) and film thickness (FT) of various cementation techniques through 3-dimensional (3D) microcomputed tomography (μCT).

Material And Methods: Forty-eight artificial plastic maxillary central incisors with standard preparations for veneers were provided by a mannequin manufacturer (P-Oclusal) and used as testing models with the manufacturer's plastic veneers.

Effect of karyotype on successful human embryonic stem cell derivation.

The success rate of human embryonic stem cell (hESC) derivation depends on both culture conditions and embryo quality and is routinely determined by morphological criteria. However, high incidence of chromosomal abnormality even in high-grade cleavage embryos from in vitro fertilization (IVF) patients suggests that the morphological grade of supernumerary embryos obtained from IVF clinics may not be a good prediction factor for successful hESC derivation. We show here that from one donor under identical derivation conditions 12 karyotypically abnormal post-bioptic embryos did not yield hESC lines, whereas two out of four normal embryos did.

Derivation of human embryonic stem cell lines from biopsied blastomeres on human feeders with minimal exposure to xenomaterials.

In a continuous effort to improve the generation of therapeutic grade human embryonic stem cell (hESC) lines, we focused on preserving developmental capacity of the embryos, minimizing the exposure to xenomaterials, increasing derivation efficacy, and reducing the complexity of the derivation procedure. In this study, we describe an improved method for efficient derivation of hESC lines from blastomeres of biopsied embryos. Our protocol substituted feeder cells of mouse origin with human foreskin fibroblasts (HFFs), limited serum exposure of cells to formation of the initial outgrowth, and increased derivation efficacy from 12.

Type-specific seroprevalence of herpes simplex virus type 2 and associated risk factors in middle-aged women from 6 countries: the IARC multicentric study.

Goal: To determine type-specific seroprevalence of herpes simplex viruses (HSV-1 and HSV-2) and HSV-2 risk factors.

Study Design: Six-hundred fifty eight middle-aged control women (hospital-based in 4 of 6 countries) from a multicenter cervical cancer case-control study participated from 1985 to 1997. Type-specific serum IgG antibodies against HSV-1 and HSV-2 were detected with Western Blot.

Cytochemical localization of acid phosphatase in Stigeoclonium tenue (Chaetophorales, Chlorophyceae).

Nonspecific acid phosphatases are a group of enzymes whose activity increases the availability of exogenous and endogenous orthophosphate either through extra- or intracellular hydrolysis of phosphate compounds. Our study demonstrates the activity of acid phosphatases in the filamentous freshwater alga Stigeoclonium tenue. These enzymes were detected following a cerium-based method in which cerium was used as an orthophosphate-capture reagent.

[Gastric cancer in Lima].

Gastric cancer continues to be one of the most common malignant neoplasias in the world. Despite the decreasing incidence of this disease in developed countries, Eastern Europe and Latin America show the highest incidences. It accounted for 8.

Serum-free derivation of human embryonic stem cell lines on human placental fibroblast feeders.

Objective: To derive new human embryonic stem cell (hESC) lines on pathogen-free human placental fibroblast feeders under serum-free conditions. Because the embryo develops in close contact with extraembryonic membranes, we hypothesized that placental mesenchyme might replicate the stem cell niche in situ.

Design: We isolated and characterized human placental fibroblast lines from individual donors and tested their ability to support growth of federally registered hESC lines.

Trisomy 21 is associated with variable defects in cytotrophoblast differentiation along the invasive pathway.

Aneuploid cells in the placenta are associated with poor pregnancy outcomes, but the mechanisms are unclear. Here, we examined the cytotrophoblast (CTB) differentiation pathway that leads to uterine invasion in pregnancies complicated by trisomy 21 (T21) as compared with their normal counterparts. Surprisingly, we observed a wide spectrum of T21 effects.

Fine structural study of the red seaweed Gymnogongrus torulosus (Phyllophoraceae, Rhodophyta).

The present study analyzed several characters of the red seaweed Gymnogongrus torulosus, such as cellular structure of the thallus, cuticle, pit plug and cell wall ultrastructure, and morphology of some organelles like plastids, Golgi bodies and mitochondria. Also, anomalous chloroplasts with thylakoid disorganization were found in medullary cells. The significance of this thylakoid disposition is still unclear.

FINE STRUCTURE OF BIFLAGELLATE ZOOSPORES OF ASTEROCOCCUS SUPERBUS (TETRASPORALES, CHLOROPHYCEAE), INCLUDING THE ABSOLUTE CONFIGURATION OF THE FLAGELLAR APPARATUS.

The ultrastructure of zoospores of Asterococcus superbus (Cienk.) Scherffel was studied to provide ultrastructural data relevant to the systematic position of the genus. Our results demonstrated that the motile cells of A.