Structure, Activation, and Regulation of NOX2: At the Crossroad between the Innate Immunity and Oxidative Stress-Mediated Pathologies.

Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) is a multisubunit enzyme complex that participates in the generation of superoxide or hydrogen peroxide (H2O2) and plays a key role in several biological functions. Among seven known NOX isoforms, NOX2 was the first identified in phagocytes but is also expressed in several other cell types including endothelial cells, platelets, microglia, neurons, and muscle cells. NOX2 has been assigned multiple roles in regulating many aspects of innate and adaptive immunity, and human and mouse models of NOX2 genetic deletion highlighted this key role. On the other side, NOX2 hyperactivation is involved in the pathogenesis of several diseases with different etiologies but all are characterized by an increase in oxidative stress and inflammatory process. From this point of view, the modulation of NOX2 represents an important therapeutic strategy aimed at reducing the damage associated with its hyperactivation. Although pharmacological strategies to selectively modulate NOX2 are implemented thanks to new biotechnologies, this field of research remains to be explored. Therefore, in this review, we analyzed the role of NOX2 at the crossroads between immunity and pathologies mediated by its hyperactivation. We described (1) the mechanisms of activation and regulation, (2) human, mouse, and cellular models studied to understand the role of NOX2 as an enzyme of innate immunity, (3) some of the pathologies associated with its hyperactivation, and (4) the inhibitory strategies, with reference to the most recent discoveries.

Toxicity assessment of nano-TiO2 in Apis mellifera L., 1758: histological and immunohistochemical assays.

The aim of this study was to evaluate the toxicity of titanium dioxide nanoparticles (TiO2 NPs) by short-term toxicity tests in Apis mellifera, considered an excellent bioindicator organism mainly due to its sensitivity. Bees have been exposed to several concentrations of TiO2 NPs (1 × 10-3 , 1 × 10-4 , 1 × 10-5 , 1 × 10-6 mg/10 ml) for 10 days. Morphostructural and histological assays were done on gut and honey sac. The research of exposure biomarkers like metallothioneins 1 (MT1) and Heat Shock Protein 70 (HSP70) was performed to verify if a detoxification mechanism has been activated in the exposed animals. No histological alteration on the epithelium of the gut and honey sac were observed in exposed samples. A significant positivity for anti-MT1 antibody was observed only in the honey sac cells. A weak positivity for HSP70 was observed in both structures analyzed. In several studies have shown the non-toxicity of TiO2 NPs on other model organisms, in our study, titanium dioxide nanoparticles was proven to be highly toxic at the highest concentration tested (100% of lethality to 1 × 10-3 mg/10 ml) and moderately toxic at lower concentrations. Honey bees proved to be excellent models for study of NPs toxicity and for monitoring environment.

Comparative evaluation of the shaping ability of two different nickel-titanium rotary files in curved root canals of extracted human molar teeth.

AIM: The aim of the present study was to compare the shaping ability of two different nickel-titanium rotary files in the curved root canals of extracted human molar teeth. METHODS: Thirty root canals of 17 extracted human molars teeth were randomly assigned to two experimental groups (n = 15): ProTaper Next and ProTaper Universal (PTU), on the basis of the rotary files system used. The final size of all apical foramina was 0.25 mm in diameter. Standardized digital radiographs were taken before and after instrumentation in both clinical and proximal views, with a size 10 K-file inserted into the canal for the determination of the angle of curvature and apical transportation. Preparation time and fractured or deformed instruments were also recorded. The unpaired Student's t-test was used to compare results. RESULTS: There was no significant difference between the two instruments with respect to canal straightening and apical transportation before and after instrumentation (P > 0.05). The use of both instruments resulted in a significant reduction in the angle of curvature after instrumentation (P < 0.05). Instrumentation time was significantly greater for PTU (P < 0.05). CONCLUSIONS: The ProTaper Universal and ProTaper Next systems performed similarly with regard to the straightening of curved root canals and apical transportation. ProTaper Next was significantly faster than ProTaper Universal.

Scale for the measurement of attitudes towards alcohol.

AIMS: The aim was to analyse the characteristics of, and validate, a new instrument in Italian, 'Scale for the measurement of attitudes towards alcohol'. The instrument is a means for assessing young people's risk profile regarding the use of alcohol and identifying the factors that contribute to determining this attitude. METHODS: The test was initially composed of 60 items divided into three domains and administered to a sample of 41 subjects. The results revealed the necessity of adapting the test's conceptual structure: consequently, the items were reduced to 35, divided into five domains. This second version was administered to a sample of 467 students attending upper secondary schools and vocational training schools in the municipality of Siena. Following this second experiment, a third version was realized, which comprised 25 items divided into the same five domains; it was administered to 100 subjects, with an equal number of males and females and an age range of 14-30 years. Analysis of the data obtained resulted in a final structure formed of 15 items in three domains. RESULTS: The final structure of the test has good psychometric properties in terms of both reliability and validity. CONCLUSIONS: The 'Scale for the measurement of attitudes towards alcohol' can be seen as an instrument for evaluating the factors capable of conditioning the behaviour of people between 18 and 26 years of age towards alcoholic substances.