Mouse TIGIT inhibits NK‐cell cytotoxicity upon interaction with PVR

The activity of natural killer (NK) cells is controlled by a balance of signals derived from inhibitory and activating receptors. TIGIT is a novel inhibitory receptor, recently shown in humans to interact with two ligands: PVR and Nectin2 and to inhibit human NK‐cell cytotoxicity. Whether mouse TIGIT (mTIGIT) inhibits mouse NK‐cell cytotoxicity is unknown. Here we show that mTIGIT is expressed by mouse NK cells and interacts with mouse PVR. Using mouse and human Ig fusion proteins we show that while the human TIGIT (hTIGIT) cross‐reacts with mouse PVR (mPVR), the binding of mTIGIT is restricted to mPVR. We further demonstrate using surface plasmon resonance (SPR) and staining with Ig fusion proteins that mTIGIT binds to mPVR with higher affinity than the co‐stimulatory PVR‐binding receptor mouse DNAM1 (mDNAM1). Functionally, we show that triggering of mTIGIT leads to the inhibition of NK‐cell cytotoxicity, that IFN‐γ secretion is enhanced when mTIGIT is blocked and that the TIGIT‐mediated inhibition is dominant over the signals delivered by the PVR‐binding co‐stimulatory receptors. Additionally, we identify the inhibitory motif responsible for mTIGIT inhibition. In conclusion, we show that TIGIT is a powerful inhibitory receptor for mouse NK cells.     

Psychopathy-associated personality traits influence crime-scene behavior in male homicide offenders

Abstract

Purpose: We investigated whether psychopathy-associated personality traits and behavioral styles affect the manner in which homicides are committed or the motives underlying them.

Materials and methods: Using three nationwide registries and an in-house homicide database based on court verdicts, we identified all cases of homicide in Sweden during the years 2007, 2008 and 2009. In 72 male offenders who had undergone assessment using the Psychopathy Checklist – Revised (PCL-R), the manner of homicide was categorized as instrumental or expressive, and the motive as belonging to one of five categories: (1) intimate-partner or family-related homicide; (2) homicide occurring during altercations, (3) robberies or burglaries, or (4) criminal conflicts; or (5) sexual homicide.

Results and conclusions: Offenders who had committed homicide in an instrumental manner or with a sexual motive had higher scores on PCL-R factor 1 than offenders displaying an expressive manner or other motives, suggesting that partially adaptive personality traits influence the crime-scene behavior of the former type of offenders more than maladaptive behavioral styles.     

Parental Education Level Is Associated With Clustering of Metabolic Risk Factors in Adolescents Independently of Cardiorespiratory Fitness,Adherence to the Mediterranean Diet,or Pubertal Stage

Few studies have reported associations between clustering metabolic risk factors and socioeconomic status (SES) in youth. This study aimed to analyze the association between clustering metabolic risk factors and SES in adolescents. It was hypothesized that SES is inversely related to clustering metabolic risk factors. This 2009 cross-sectional school-based study investigated 517 Portuguese adolescents ages 15–18 years. The study considered the age- and sex-adjusted z-scores for the ratio of total cholesterol/high-density lipoprotein, homeostasis model, triglycerides, and systolic blood pressure, and a metabolic risk score was constructed by summing all the z-scores (≥1 standard deviation was considered high risk). Cardiorespiratory fitness was estimated by the 20 m shuttle-run test and dietary intake by a food frequency questionnaire. The best of parental education was used as a proxy measure of SES. The results showed that adolescents with low SES were more likely to have a high metabolic risk score (odds ratio [OR], 1.96; p < 0.020) regardless of cardiorespiratory fitness, adherence to the Mediterranean diet, or pubertal stage. In conclusion, a lower SES was associated with increased risk for a high metabolic risk score among Azorean adolescents after adjustment for pubertal stage, adherence to the Mediterranean diet, and cardiorespiratory fitness. Future health-promotion strategies among Azorean adolescents should consider the impact of SES on their health.     

The influence of different radiopacifying agents on the radiopacity,compressive strength,setting time,and porosity of Portland cement

Objectives

The aims of this study were to evaluate the radiopacity, compressive strength, setting time, and porosity of white Portland cement (PC) with the addition of bismuth oxide (Bi₂O₃), zirconium dioxide (ZrO₂), and ytterbium trifluoride (YbF₃) after immersion at 37 °C for 7 days in distilled water or phosphate buffer saline.

Materials and methods

Specimens measuring 8 mm in diameter and 1 mm in thickness were fabricated from PC with the addition of 10, 20, and 30 wt% Bi₂O_3, ZrO₂ or YbF₃. ProRoot MTA (Dentsply, Tulsa, OK, USA) and pure PC were used as controls. For radiopacity assessments, specimens were radiographed alongside a tooth slices and an aluminum stepwedge on Extraspeed occlusal dental films (Insight Kodak, Rochester, New York). Mean optical density of each specimen was calculated and used to express radiopacity of the material as an equivalent thickness of aluminum. Compressive strength was measured by using 4-mm diameter and 6-mm high specimens and Universal testing machine. High-pressure mercury intrusion porosimeter (Carlo Erba Porosimeter 2000) was employed to measure the porosity of the specimens. The setting time was measured by using a needle of 100 g in weight. The morphology of specimens was evaluated using a scanning electron microscope (TESCAN Mira3 XMU, USA Inc.). Data were analyzed by one-way ANOVA and post hoc Tukey test (P?<?0.05).

Results

The PC with the addition of at least 10 wt% Bi₂O₃ and 20 wt% ZrO₂ or YbF₃ demonstrated greater radiopacity value than the recommended 3 mmAl cut-off. ZrO₂ and YbF₃ increased the compressive strength of PC, but it was not statistically significant (P?>?0.05), while Bi₂O₃ decreased it (P?<?0.05). All radiopacifiers significantly increased the porosity of the experimental cements (P?<?0.05). Bi₂O₃ extended the setting time of PC (P?<?0.05), whilst ZrO₂ and YbF₃ did not significantly affect it (P?>?0.05).

Conclusions

ZrO₂ and YbF₃ may be used as a suitable alternative to replace Bi₂O₃ in MTA without influencing its physical properties.