An in vitro study on the maturation of conventional glass ionomer cements and their interface to dentin

The objective of the study was to investigate the influence of long-term storage (up to 1 year) and coating on the variation of micro-mechanical properties of four conventional restorative glass ionomer cements (GICs) within 3.5 mm deep class I cavities. Four commercially available GICs (Riva Self Cure (SDI), ChemFil Rock (Dentsply), Fuji IX Fast and Fuji IX GP Extra/Equia (GC)) were applied to 100 teeth. In each tooth, two similar 3.5 mm deep class I cavities were prepared and filled with the GICs, with and without resin coating. The samples were stored in artificial saliva at 37 °C for 1 week, 1 month, 3 months, 6 months and 1 year. The variation in mechanical properties (indentation modulus (E) and Vickers hardness (HV)) were determined in 100 μm steps starting from the filling surface, through the intermediate layer in between dentine and GIC, and ending 100 μm in dentin. HV and E were strongly influenced by the material (P < 0.05, partial eta-squared η_P² = 0.31 and 0.23) but less by aging duration (P < 0.05, η_P² = 0.02 and 0.12) and resin coating (P < 0.05, η_P² = 0.02 and 0.03). The depth of measurement (0–2 mm) has no influence on HV (P = 0.789). HV shows a gentle increase over the 1 year storage period (P = 0.002). A ～300 μm GIC zone at the areas close to dentin with weaker properties as those measured in dentin or GIC was identified in all fillings, irrespective of the presence of coating, and at all storage periods. The thickness of this zone is more strongly influenced by storage (P < 0.05, η_P² = 0.081) than by material type (P < 0.05, η_P² = 0.056), while coating showed no influence (P = 0.869). Filler morphology and dimension were similar to upper parts of the GIC filling; however, the amount of low cations was higher. We concluded that the development of an intermediate layer in between dentine and GIC with lower mechanical properties might be responsible for the bond quality of GIC to dentine. Moreover, class I GIC restorations are unlikely to feature constant mechanical properties throughout the cavity, regardless of conditions such as aging and coating.     

Functional communication and executive function in aphasia

The purpose of this exploratory study was to investigate the relationship between functional communication and executive function ability in aphasia. Twenty‐five participants with aphasia underwent examination with an extensive test battery including measures of functional communication, executive function ability, and language impairment. Compared to published norms, most participants did not perform within normal limits on the executive function tests. As expected, the correlation between severity of language impairment and functional communication ratings exceeded that among the executive functioning and functional communication measures. Eight of ten correlation coefficients for the relationship between executive functioning and functional communication reached statistical significance suggesting a clear relationship between scores on the executive functioning measures and functional communication ability. Based on these results, it appears that decreased executive functioning ability may coincide with decreased functional communication ability in persons with aphasia.     

Why are infants held on the left? A test of the attention hypothesis with a doll,a book,and a bag

Most adults, especially women, hold infants and objects representing infants, such as dolls, preferentially on the left side. The attention hypothesis credits the effect to left-directed attention for perception of emotionally salient targets, faces being prime examples. Support comes from studies showing stronger left visual hemispace (LVH) biases in left-holders than right-holders on the Chimeric Faces Test (CFT), but control tests with non-social/emotional objects are needed. We therefore observed young women holding a doll, a book, and a bag, and compared their scores with their performance on the CFT. We also assessed their handedness to check on its possible role. Overall, only the doll elicited a significant side bias, with 57% of all holds on the left, 2% in the middle, and 41% on the right. On the CFT, only left-holders had an LVH bias, whereas right-holders had no bias in either direction. Only the doll-hold scores were consistently related to CFT scores, and for none of the objects was handedness related to side-of-hold.     

Mothers’ and fathers’ lateral biases for holding their newborn infants: A study of images from the World Wide Web

Photographic and direct-observation studies show that most adults hold infants on the left side. This basic directional effect is well established, but other details are still uncorroborated, uncertain, or inconsistent across studies. These include the overall strength of the bias, the role of the sex, parental status, and experience of the holder, and the sex and age of the infant. Given their importance for understanding the bias, we sought further information from a large sample of photographs of mothers and fathers, some of them first-time parents, others not, holding their infants in the first minutes, hours, or days after birth. The results confirmed the basic directional effect and provided information on the other variables. They also raise questions for further research, especially as it pertains to the use of photographs vs direct observation.     

Vitamin D binding protein and vitamin D in human allergen‐induced endobronchial inflammation

Allergic asthma is a chronic disease of the airways associated with airway hyperresponsiveness, a variable degree of airflow obstruction, airway remodelling and a characteristic airway inflammation. Factors of the vitamin D axis, which include vitamin D metabolites and vitamin D binding protein (VDBP), have been linked to asthma, but only few data exist about their regulation in the lung during acute allergen‐induced airway inflammation. Therefore, we analysed the regulation of factors of the vitamin D axis during the early‐ and late‐phase reaction of allergic asthma. Fifteen patients with mild allergic asthma underwent segmental allergen challenge. VDBP was analysed in bronchoalveolar lavage fluid (BALF) and serum using the enzyme‐linked immunosorbent assay (ELISA) technique. 25‐hydroxyvitamin D₃ [25(OH)D₃] and 1,25‐dihydroxyvitamin D₃ [1,25(OH)₂D₃] were analysed by a commercial laboratory using the liquid chromatography–mass spectrometry (LC/MS) technique. VDBP (median 2·3, range 0·2–7·1 μg/ml), 25(OH)D₃ (median 0·060, range < 0·002–3·210 ng/ml) and 1,25(OH)₂D₃ (median < 0·1, range < 0·1–2·8 pg/ml) were significantly elevated in BALF 24 h but not 10 min after allergen challenge. After correction for plasma leakage using the plasma marker protein albumin, VDBP and 25(OH)D₃ were still increased significantly while 1,25(OH)₂D₃ was not. VDBP and 25(OH)D₃ were correlated with each other and with the inflammatory response 24 h after allergen challenge. Serum concentrations of all three factors were not influenced by allergen challenge. In conclusion, we report a significant increase in VDBP and 25(OH)D₃ in human BALF 24 h after allergen challenge, suggesting a role for these factors in the asthmatic late‐phase reaction.     

Pharmacological rescue of Ras signaling,GluA1-dependent synaptic plasticity,and learning deficits in a fragile X model

Fragile X syndrome, caused by the loss of Fmr1 gene function, is the most common form of inherited mental retardation, with no effective treatment. Using a tractable animal model, we investigated mechanisms of action of a few FDA-approved psychoactive drugs that modestly benefit the cognitive performance in fragile X patients. Here we report that compounds activating serotonin (5HT) subtype 2B receptors (5HT_2B-Rs) or dopamine (DA) subtype 1-like receptors (D₁-Rs) and/or those inhibiting 5HT_2A-Rs or D₂-Rs moderately enhance Ras–PI3K/PKB signaling input, GluA1-dependent synaptic plasticity, and learning in Fmr1 knockout mice. Unexpectedly, combinations of these 5HT and DA compounds at low doses synergistically stimulate Ras–PI3K/PKB signal transduction and GluA1-dependent synaptic plasticity and remarkably restore normal learning in Fmr1 knockout mice without causing anxiety-related side effects. These findings suggest that properly dosed and combined FDA-approved psychoactive drugs may effectively treat the cognitive impairment associated with fragile X syndrome.