Porphyromonas gingivalis LPS stimulation downregulates DNMT1, DNMT3a, and JMJD3 gene expression levels in human HaCaT keratinocytes

Objective

The role of epigenetic regulation in inflammatory diseases such as periodontitis is poorly known. The aim of this study was to assess whether Porphyromonas gingivalis lipopolysaccharide (LPS) can modulate gene expression levels of the some enzymes that promote epigenetic events in cultures of the human keratinocytes and gingival fibroblasts. In addition, the same enzymes were evaluated in gingival samples from healthy and periodontitis-affected individuals.

Materials and methods

Primary gingival fibroblast and keratinocyte (HaCaT) cultures were treated with medium containing P. gingivalis LPS or P. gingivalis LPS vehicle for 24 h. After this period, cell viability was assessed by MTT test and total RNA extracted to evaluate gene expression levels of the following enzymes by qRT-PCR: DNA methyltransferase 1 (DNMT1), DNA methyltransferase 3a (DNMT3a), histone demethylases Jumonji domain containing 3 (JMJD3) and ubiquitously transcribed tetratricopeptide repeat, X chromosome (UTX). To evaluate gene expression in healthy and periodontitis-affected individuals, total RNA was extracted from biopsies of gingival tissue from healthy and periodontitis sites, and gene expression of DNMT1, DNAMT3a, JMJD3, and UTX was evaluated by qRT-PCR.

Results

No significant differences were found in the gene expression analysis between healthy and periodontitis-affected gingival samples. The results showed that LPS downregulated DNMT1 (p?<?0.05), DNMT3a (p?<?0.05), and JMJD3 (p?<?0.01) gene expression in HaCaT cells, but no modulation was observed in gingival fibroblasts.

Conclusion

P. gingivalis LPS exposure to human HaCaT keratinocytes downregulates gene expression of the enzymes that promote epigenetic events.

Clinical relevance

The advance knowledge about epigenetic modifications caused by periodontopathogens may to possibly led to the development of new periodontal therapies.     

Clinical evaluation of the performance and safety of a new dentine substitute, Biodentine, in the restoration of posterior teeth — a prospective study

Objectives

A multicentric randomized, 3-year prospective study was conducted to determine for how long Biodentine, a new biocompatible dentine substitute, can remain as a posterior restoration.

Materials and methods

First, Biodentine was compared to the composite Z100®, to evaluate whether and for how long it could be used as a posterior restoration according to selected United States Public Health Service (USPHS)’ criteria (mean ± SD). Second, when abrasion occurred, Biodentine was evaluated as a dentine substitute combined with Z100®.

Results

A total of 397 cases were included. This interim analysis was conducted on 212 cases that were seen for the 1-year recall. On the day of restoration placement, both materials obtained good scores for material handling, anatomic form (0.12?±?0.33), marginal adaptation (0.01?±?0.10) and interproximal contact (0.11?±?0.39). During the follow-up, both materials scored well in surface roughness (≤1) without secondary decay and post-operative pain. Biodentine kept acceptable surface properties regarding anatomic form score (≤1), marginal adaptation score (≤2) and interproximal contact score (≤1) for up to 6 months after placement. Resistance to marginal discoloration was superior with Biodentine compared to Z100®. When Biodentine was retained as a dentine substitute after pulp vitality control, it was covered systematically with the composite Z100®. This procedure yielded restorations that were clinically sound and symptom free.

Conclusions

Biodentine is able to restore posterior teeth for up to 6 months. When subsequently covered with Z100®, it is a convenient, efficient and well tolerated dentine substitute.

Clinical relevance

Biodentine as a dentine substitute can be used under a composite for posterior restorations.     

Cellular proliferation markers in peripheral and central fibromas: a comparative study

Objective:

To perform a comparative study of the cellular proliferation in the peripheral and central fibromas.

Material and Methods:

Immunohistochemistry for PCNA and the AgNOR technique were performed in 9 cases of peripheral odontogenic fibroma (POF), in 4 cases of odontogenic fibroma (OdF), in 8 cases of peripheral ossifying fibroma (PEOF) and 7 cases of ossifying fibroma (OsF). The Kruskal-Wallis and Mann-Whitney tests were used for the statistical analyses.

Results:

Mesenchymal component of the central lesions presented a higher mean number of AgNOR per nucleus and PCNA index than did the peripheral lesions (P≤0.05). The mean number of AgNOR per nucleus in the epithelial component proved to be higher in the OdF than in the POF (P≤0.05). The mesenchymal and epithelial components presented similar mean numbers of AgNOR per nucleus and PCNA index in the OdF, as well as a similar mean number of AgNOR per nucleus in the POF.

Conclusions:

The mesenchymal component may well play a role in the differences between the biological behaviour of the central lesions as compared to the peripheral lesions. Moreover, considering that the epithelial and mesenchymal components in odontogenic fibromas presented a similar proliferation index, more research is warranted to understand the true role of the epithelial components, which are believed to be inactive in nature, as well as in the development and biological behaviour of these lesions.     

Gray matter abnormalities in patients with narcissistic personality disorder

Background

Despite the relevance of narcissistic personality disorder (NPD) in clinical settings, there is currently no empirical data available regarding the neurobiological correlates of NPD. In the present study, we performed a voxel-based morphometric analysis to provide initial insight into local abnormalities of gray matter (GM) volume.

Methods

Structural brain images were obtained from patients with NPD (n = 17) and a sample of healthy controls (n = 17) matched regarding age, gender, handedness, and intelligence. Groups were compared with regard to global brain tissue volumes and local abnormalities of GM volume. Regions-of-interest analyses were calculated for the anterior insula.

Results

Relative to the control group, NPD patients had smaller GM volume in the left anterior insula. Independent of group, GM volume in the left anterior insula was positively related to self-reported emotional empathy. Complementary whole-brain analyses yielded smaller GM volume in fronto-paralimbic brain regions comprising the rostral and median cingulate cortex as well as dorsolateral and medial parts of the prefrontal cortex.

Conclusion

Here we provide the first empirical evidence for structural abnormalities in fronto-paralimbic brain regions of patients with NPD. The results are discussed in the context of NPD patients' restricted ability for emotional empathy.     

Hypothermia After CPR Prolongs Conduction Times of Somatosensory Evoked Potentials

Background

To investigate the effect of mild hypothermia on conduction times and amplitudes of median nerve somatosensory evoked potentials (SEP) in patients after cardiopulmonary resuscitation (CPR).

Methods

Patients treated with hypothermia after CPR who underwent SEP recording during hypothermia and after rewarming were selected from a prospectively collected database. Latencies and amplitudes of N9 (peripheral conduction time, PCT), N13, and N20 were measured. The central conduction time (CCT) was defined as peak–peak latency N13–N20. Recordings of 25 patients were assessed by a second observer to determine the intraclass correlation coefficient (ICC).

Results

A total of 115 patients were included. The mean body temperature at SEP during hypothermia was 33.1 °C (SD 0.8) and after rewarming 37.1 °C (SD 0.8). Mean latencies of N9, N13, and N20 and mean CCT were longer during hypothermia. There were no consistent differences in amplitudes. There was an almost perfect ICC for assessment of latencies and amplitudes.

Conclusions

This study showed that PCT and CCT of median nerve SEP were prolonged during treatment with hypothermia after CPR compared with after rewarming. Amplitudes did not differ consistently.     

Determinants of infant formula use and relation with growth in the first 4 months

The wide variety of infant formula available on the market can be confusing for parents and physicians. We aimed to determine associations between predominant type of formula used from birth to 4 months and parental and child characteristics and type of physician consulted, and then to describe relations between type of formula used and growth. Our analyses included 1349 infants from the EDEN mother–child cohort. Infant's feeding mode and type of formula used were assessed at 4 months by maternal self‐report. Infant's weight and height from birth to 4 months, measured in routine follow‐up, were documented by health professionals in the infant's personal health record. Anthropometric z‐scores were calculated by using World Health Organization growth standards. Multinomial logistic regression was used to identify factors associated with the type of formula predominantly used; relations with growth were analysed by linear regressions. Partially hydrolysed formulas were more likely to be used by primiparous women (P < 0.001), those breastfeeding longer (P < 0.001) and for infants with family history of allergies (P = 0.002). Thickened formulas were more often used by mothers returning to employment in the first 4 months (P = 0.05) and breastfeeding shortly (P < 0.001). No significant relation was found between infant's growth and type of formula (P > 0.20). Infants breastfed shorter showed higher weight‐for‐age (P < 0.001) and length‐for‐age (P = 0.001) z‐score changes between birth and 4 months. The use of a specific type of infant formula seems to be mainly related to parental characteristics. Infant's growth in the first 4 months is related to other factors than to the type of formula used.     

Tolerogenic microenvironment in neonatal period induced by maternal immunization with ovalbumin

Maternal immunization with allergens, such as ovalbumin (OVA), can inhibit the development of an allergic response in offspring. The regulatory mechanisms seem to be mediated by maternal antibodies (MatAbs) and factors generated by the maternal–fetal interface. The aim of this study was to verify the pathways of inhibitory Ab transference after maternal immunization with OVA and the effect of the offspring's dendritic cells (DCs) on the generation of regulatory T (Treg) cells. We verified that preconceptional OVA immunization induces high levels of proinflammatory and regulatory cytokines in the amniotic fluid, allowing the transference of high levels of anti-OVA IgG1 Abs to the offspring. Using an adoptive nursing protocol, we verified that maternal immunization leads to MatAb transference by the placental route and by breastfeeding contribute to the inhibition of anaphylactic IgE and IgG1 Ab responses in immunized offspring. We observed that maternal immunization decreased eosinophil numbers in recovered bronchoalveolar lavage fluid and in the lung tissue, whereas with a lack of control of airway responsiveness to methacholine. Maternal immunization induced in young offspring a decreased percentage of CD11c+ DCs expressing MHC class II and CD40 molecules. Moreover, DCs from both groups of offspring when pulsed with OVA, were able to induce Treg cells in vitro. Similarly, OVA immunization at the neonatal stage increased the frequency of Treg cells, regardless of the mother's immunization status. These findings emphasize that maternal immunization leads to a complex interaction of regulatory factors, with MatAbs, DCs and Treg cells affecting the tolerance of offspring during an allergic response.     

Seed oil of Joannesia princeps improves cutaneous wound closure in experimental mice

Joannesia princeps (Cotieira) is a well known medicinal plant in Brazil, however, the therapeutic effects of oil obtained from its seeds have still not been demonstrated. The beneficial effects of J. princeps seed oil on cutaneous wound healing on the back of experimental mice were investigated. An excisional lesion in male Swiss mice (n = 20 per group) was topically treated with mineral oil or J. princeps seed oil once a day beginning on the day of lesion until the third day after wounding. Animals were killed and lesions collected after 14 days. Murine skin fibroblast cultures were treated with J. princeps seed oil and fibroblast activity was evaluated. In the in vivo assay, J. princeps seed oil increased wound contraction and migratory tongue length, but reduced neutrophil and macrophage number when compared with the control group. Blood vessel number, collagen deposition, and VEGF levels were increased in treated lesions when compared with control lesions. However, J. princeps seed oil reduced myofibroblast density and carbonyl protein levels when compared with the control group. In the in vitro assay, treatment with J. princeps seed oil increased fibroblast migration and proliferation, but reduced myofibroblastic differentiation in vitro. In conclusion, J. princeps seed oil accelerates wound closure increasing angiogenesis, keratinocyte migration, and fibroblast activity while reducing inflammatory response and oxidative damage.