Ternary Graphene Oxide and Titania Nanoparticles-Based Nanocomposites for Dye Photocatalytic Degradation: A Review.

Advanced oxidation processes stand as green alternatives for the decontamination of waste waters. Photocatalysis is an advanced oxidation process in which a semiconductor material absorbs photon energy and triggers redox reactions capable of degrading organic pollutants. Titanium dioxide (TiO2, titania) represents one of the most popular choices of photocatalytic materials, however the UV-activation of its anatase phase and its high charge recombination rate decrease its photocatalytic activity and weaken its potential. Graphene oxide is a 2D carbon nanomaterial consisting of exfoliated sheets of hexagonally arranged carbons decorated with oxygen- and hydrogen- functional groups. Composite nanomaterials consisting of titania nanoparticles and graphene oxide have proven to enhance the photocatalytic activity of pure TiO2. In this review, we present a thorough literature review of ternary nanocomposites based on synthesized or commercial titania nanoparticles and GO (or reduced GO) particularly used for the photodegradation of dyes. GO/TiO2 has been enriched primarily with metals, semiconductors and magnetic nanomaterials, proving a superior dye degradation performance and reusability compared to bare TiO2. Ongoing challenges and perspectives are outlined.

Novel dehydroepiandrosterone benzimidazolyl derivatives as 5α-reductase isozymes inhibitors.

5α-R isozymes (types 1 and 2) play an important role in prostate gland development because they are responsible for intraprostatic dihydrotestosterone (DHT) levels when the physiological serum testosterone (T) concentration is low. In this study, we synthesized seven novel dehydroepiandrosterone derivatives with benzimidazol moiety at C-17, and determined their effect on the activity of 5α-reductase types 1 and 2. The derivatives with an aliphatic ester at C-3 of the dehydroepiandrosterone scaffold induced specific inhibition of 5α-R1 activity, whereas those with a cycloaliphatic ester (cyclopropyl, cyclobutyl, or cyclopentyl ring) or an alcohol group at C-3 inhibited the activity of both isozymes. Derivatives with a cyclohexyl or cycloheptyl ester at C-3 showed no inhibitory activity. In pharmacological experiments, derivatives with esters having an alcohol or the aliphatic group or one of the three smaller cycloaliphatic rings at C-3 decreased the diameter of male hamster flank organs, with the cyclobutyl and cyclopentyl esters exhibiting higher effect. With exception of the cyclobutyl and cyclopentyl esters, these compounds reduced the weight of the prostate and seminal vesicles.

Another body project: the thin ideal, motherhood, and body dissatisfaction among Mexican women.

In this article, we examine the bodily experiences of Mexican women, to investigate their acceptance of the thin ideal and resulting body dissatisfaction. We conducted semi-structured individual interviews with 30 adult participants in Mexico City. Interviewees accepted the thin body ideal, but experiencing their bodies as signifiers of motherhood protected them from body dissatisfaction. Instead of a personal body project, they engaged in a project of caring for their children's bodies. We suggest that health campaigns directed to adult women should consider the relational aspects of their lives.

Natural history of Helicobacter pylori infection in Mexican schoolchildren: incidence and spontaneous clearance.

OBJECTIVES: The aim of the present study was to estimate the incidence and spontaneous clearance rate of Helicobacter pylori infection and the effect of some variables on these outcomes in schoolchildren. METHODS: From May 2005 to December 2010, 718 schoolchildren enrolled in 3 public boarding schools in Mexico City participated in the follow-up. At the beginning of the study and every 6 months thereafter, breath samples were taken to detect H pylori infection; blood samples and anthropometric measurements were taken to evaluate nutritional status. Data on sociodemographic characteristics were collected. RESULTS: The prevalence of H pylori infection was 38%. The incidence rate was 6.36%/year. Schoolchildren with anemia or iron deficiency at the beginning of the study (who received iron supplements) showed a higher infection acquisition rate than those with normal iron nutritional status, hazard ratio (HR) 12.52 (95% confidence interval [CI] 4.01%-39.12%), P < 0.001 and HR 2.05 (95% CI 1.09%-3.87%), P = 0.027, respectively. The spontaneous clearance rate of the infection was 4.74%/year. The spontaneous clearance rate was higher in children who had iron deficiency (who received iron supplements), HR 5.02 (95% CI 1.33%-18.99%), P = 0.017, compared with those with normal nutritional iron status. It was lower in schoolchildren with ≥ 2 siblings compared with schoolchildren with 1 or no siblings, HR 0.23 (95% CI 0.08%-0.63%), P = 0.004. CONCLUSIONS: H pylori infection status is dynamic in schoolchildren. Variables related to health status and infection transmission, such as iron status and number of siblings, are important for the incidence and spontaneous clearance of H pylori infection.

Trastornos ansiosos y desórdenes temporomandibulares en funcionarios de un centro de salud familiar en la comuna de Concepción, Chile / Temporomandibular and anxiety disorders in workers of a family health center in the area of Concepción, Chile

Los trastornos temporomandibulares (TTMs) involucran los músculos de la masticación, articulación temporomandibular (ATM) y otras estructuras asociadas a la cavidad oral y representan un conjunto de disfunciones de la articulación, a la cual se le asocia una naturaleza multifactorial, condición que puede llegar a tener de un 50 a 93 por ciento de prevalencia en la población y cuya etiología es asociada a estrés y/o estados psicológicos alterados. Se efectuó un estudio descriptivo observacional de corte transversal con el objetivo de determinar la prevalencia de Trastornos Ansiosos y TTM, en funcionarios del Centro de Salud Familiar (CESFAM) Tucapel, sector Barrio Norte, en la comuna de Concepción. De los 97 funcionarios, 79 aceptaron voluntariamente a participar del estudio y todos trabajan directamente con pacientes en un sector con numerosos problemas socioeconómicos y laborales. Se aplicó una encuesta orientada a la pesquisa tanto de patologías psicológicas, como signos y síntomas de TTM, además de un examen extra e intraoral complementario. En los encuestados se encontró trastornos ansiosos y estados asociados a burnout en un 81 y 27,8 por ciento respectivamente, además había TTM en un 98.7 por ciento de origen multifactorial, pero presente en todos los individuos encuestados y examinados con trastornos ansiosos y estados asociados a burnout.

Temporomandibular disorders (TMDs) involve the muscles of mastication, temporomandibular joint (TMJ) and other structures associated with the oral cavity and represent a multifactorial nature of disorders associated to this joint, condition that is in the range of 50 to 93 percent of prevalence in the population and whose etiology is associated with stress and / or altered psychological states. The present study is a descriptive cross-sectional observational in order to determine the prevalence of anxiety disorders and TMD in workers of the Tucapel Family Health Center (CESFAM), Barrio Norte, in Concepción’s commune. Of the 97 staff, 79 agreed to take part voluntarily of the study, all of these people also work directly with patients at a sector with numerous socioeconomic and employment problems. A survey aimed toward the inquiry of psychological, TMD (signs and symptoms) and extra-intra oral complementary examination, was conducted. Anxiety disorders and burnout associated conditions were found (81 and 27.8 percent respectively), multifactorial TMD was also reported (98.7 percent) but present in all individuals with anxiety disorders and conditions associated to burnout.

Association of Helicobacter pylori infection and height of Mexican children of low socioeconomic level attending boarding schools.

This study evaluated the association between Helicobacter pylori infection and height in a population of schoolchildren of a low socioeconomic level regarding growth-related micronutrient status. It was a cross-sectional study of 685 children 5-13 years of age. Height and weight were recorded, a (13)C urea breath test was performed for detection of H. pylori, and a blood sample was obtained for determination of micronutrient status. Helicobacter pylori infection was found to be associated with the height of children. Children with H. pylori infection are, on average, 1.32 cm lower (95% confidence interval [CI] = -2.22 to -0.42) in height than children without infection. There was an effect modification by age: for every one-year increase in age, height was 0.66 cm less (95% CI = -1.17 to -0.15) in children with H. pylori infection. This finding suggests that H. pylori infection has a negative effect on the growth of children.

Bovine cementum extrac influences murine dental follicle cells in vitro

This study evaluated the attachment, chemo-attractive, proliferative and mineralization inductive potential of a bovine cementum extract (CPE) on newborn murine dental follicle cells (MDFC) in vitro. Cementum extract was partially purified by DEAE-cellulose chromatografy. A band representing and Mr of 55,000 was excised form the fel and the protein (s) were electroeluted. Attachment assays revealed that CPE (1.0 µg/ml) promoted MDFC attachment by 96 percent in comparison with collagen type I (5 µg/ml), and was five-fold greater compared with serum-free media (SFM), (p<0.05). Between 1 and 5 days CPE at 1.0 µg/ml and collagen type I at 5 µg/ml sustained more than 75 percent attachement and spreading of MDFC when compared to SFM (P<0.05). Contrary to other reports, fibronectin (0.5 µg/ml) was more potent than CPE in promoting MDFC chemoattraction (P<0.05). MDFC proliferation was stimulated by CPE (0.125 µg/ml), but this response was elicited only when CPE was used together with 10 percent FBS (37.3 percent) or 0.2 percent FBS (76 percent) (p<0.05). Alkaline phosphatase expression by MDFC was increased by CPE (1.0 µg/ml), in comparison to the control. Calcium deposits were detected by von Kossa staining in 14-day MDFC cultures treated with CPE. Nodule formation and its mineralization in long-term MDFC cultures were induced by CPE (1.0 µg/ml). Molecules(s) contained in CPE appear to regulate various biological activities in MDFC, indicating that CPE could play a key role in selecting progenitor cells required for the process of cementogenesis during development

Recombination of epithelial root sheath and dental papilla cells in vitro

Hertwing's epithelial root sheath (HERS) cells were isolated and recombined with ectomesenchymal cells in vitro utilizing extracellular matrix components as substrate. After 14 days in culture, HERS cells were differnetiated and exhibited a stratified organization. These features resembled those observed in vivo as epithelial rests of Malassez. A mineralization process was also present in HERS cells, in which calcium salts were deposited. This mineralization was correlated with the strong immunoexpression of osteopontin by HERS. The results obtained add support to the possible role of HERS in the secretion of Hypocalcified material on the root during early cementogenesis