Antitumor effect of bromo-naphthoquinone associated with tannic acid in triple negative breast cancer cells.

Triple-negative breast cancer (TNBC) is an aggressive type of tumor that tends to recur in women. It is characterized by the absence of hormonal receptors, making it challenging to diagnosis and treatment. In this study, we investigated the anti-tumor effects of a pro-oxidant naphthoquinone derivative called bromo-naphthoquinone (BrNQ) isolated and combined with the antioxidant tannic acid (TA) in order to improve treatment.

Increase of complex I and reduction of complex II mitochondrial activity are possible adaptive effects provoked by fluoride exposure.

Fluoride (F) can induce changes in the expression of several liver proteins, most of them localized in the mitochondria and its effect is dose- and time-dependent. This study analyzed the effect of distinct F concentrations and exposure periods on the mitochondrial activity of complex I-III and II-III in the liver. Thirty-six 21-day-old male Wistar rats were divided into 2 groups (n = 18) according to the duration of the treatment (20 or 60 days).

Proposed mechanism for understanding the dose- and time-dependency of the effects of fluoride in the liver.

Fluoride (F) can induce changes in the expression of several liver proteins. It is suggested that these changes are dose- and time-dependent. The objective of this study was to analyze the effect of different F concentrations and exposure times to this ion on the pattern of protein expression in the liver of rats.

Fluoride affects bone repair differently in mice models with distinct bone densities.

We grouped mice [strains: C57BL/6J (n=32) and C3H/HeJ (n=32)] to address the influence of bone density on fluoride's (F's) biological effects. These animals received low-fluoride food and water containing 0 (control group) or 50ppm of F for up to 28days. The upper left central incisor was extracted, and the left maxilla was collected at 7, 14, 21, and 28days for histological and histomorphometric analysis to estimate bone neoformation.

Fluoride Intensifies Hypercaloric Diet-Induced ER Oxidative Stress and Alters Lipid Metabolism.

Background: Here, we evaluated the relationship of diet and F-induced oxidative stress to lipid metabolism in the liver of rats eating normocaloric or hypercaloric diets for two time periods (20 or 60 days).

Methods: Seventy-two 21-day-old Wistar rats were divided into 2 groups (n = 36) based on the type of diet they were eating; each of these groups was then further divided into another two groups (n = 18) based on the time periods of either 20 or 60 days, for a total of four groups. Each of these was divided into 3 subgroups (n = 6 animals/subgroup), dependent on the dose of F administered in the drinking water (0 mg/L(control), 15 mg/L or 50 mg/L).

Influence of iron on modulation of the antioxidant system in rat brains exposed to lead.

The objective of this study was to evaluate markers of oxidative stress in the brains of rats exposed to lead acetate (Pb(C H O ) ), either associated or not associated with ferrous sulfate (FeSO ). A total of 36 weaning rats (Rattus norvegicus) were divided into 6 groups of six animals and exposed to lead acetate for six weeks. In the control group (control), the animals received deionized water.

Identification of a selective inhibitor of murine intestinal alkaline phosphatase (ML260) by concurrent ultra-high throughput screening against human and mouse isozymes.

Alkaline phosphatase (AP) isozymes are present in a wide range of species from bacteria to man and are capable of dephosphorylation and transphosphorylation of a wide spectrum of substrates in vitro. In humans, four AP isozymes have been identified-one tissue-nonspecific (TNAP) and three tissue-specific-named according to the tissue of their predominant expression: intestinal (IAP), placental (PLAP) and germ cell (GCAP) APs. Modulation of activity of the different AP isozymes may have therapeutic implications in distinct diseases and cellular processes.

Effects of fluoride in bone repair: an evaluation of RANKL, OPG and TRAP expression.

The objective of this study was to evaluate comparatively the effect of fluoride in the expression of the receptor activator of nuclear factor kappa B ligand (RANKL), osteoprotegerin (OPG) and tartrate-resistant acid phosphatase (TRAP) in alveolar bone repair in rats. We used 3 groups of male Wistar rats (n = 5/group), which received drinking water containing different doses of F (NaF): 0, 5 and 50 ppm, for 60 days before the incisors extraction. The upper incisors were extracted and the animals were killed 7, 14, 21 and 30 days after extraction.

[Manipulation of the human genome: ethics and law].

The molecular biology has provided the basic tool for geneticists deepening in the molecular mechanisms that influence different diseases. It should be noted the scientific and moral responsibility of the researchers, because the scientists should imagine the moral consequences of the commercial application of genetic tests, since this fact involves not only the individual and their families, but the entire population. Besides being also necessary to make a reflection on how this information from the human genome will be used, for good or bad.

Recovery of silver residues from dental amalgam.

Unlabelled: Dental amalgam residues are probably the most important chemical residues generated from clinical dental practice because of the presence of heavy metals among its constituents, mainly mercury and silver.

Objective: The purpose of this study was to develop an alternative method for the recovery of silver residues from dental amalgam.

Material And Methods: The residue generated after vacuum distillation of dental amalgam for the separation of mercury was initially diluted with 32.

Effect of calcium pre-rinse and fluoride dentifrice on enamel and on dental plaque formed in situ.

Purpose: The aim of this in situ double-blind randomised crossover study was to investigate the effect of calcium (Ca) pre-rinse on the composition of plaque and on enamel prior to the use of fluoride (F) dentifrice.

Materials And Methods: During four phases (14 days each) of this study, 10 volunteers had agreed to wear dental appliances containing two healthy bovine enamel blocks. A fresh solution containing 20% weight/volume (w/v) sucrose was dripped on the enamel blocks ex vivo for 5 min three times a day.

Optimizing the procedure for mercury recovery from dental amalgam.

Mercury, as any other heavy metal, may cause environmental damages due to its accumulation and biotransformation. Dental offices, whether private or institutional, use dental amalgam as a restorative material on a daily basis. Dental amalgam is composed of mercury (50%), silver (30%) and other metals.

Effect of calcium pre-rinse and fluoride dentifrice on remineralisation of artificially demineralised enamel and on the composition of the dental biofilm formed in situ.

Objective: This in situ blind crossover study investigated the effect of calcium (Ca) rinse prior to the use fluoride (F) dentifrice on remineralisation of artificially demineralised enamel and on the composition of biofilm.

Design: During four phases of 14 days, 10 volunteers wore appliances containing two artificially demineralised bovine enamel blocks. Three times a day, they rinsed with 10 mL of Ca (150 mM) or placebo rinse (1 min).