The role of cytokines in a Porphyromonas gingivalis-induced murine abscess model

INTRODUCTION: Porphyromonas gingivalis is an important periodontopathic bacterium that is strongly associated with periodontal disease and is part of human dental plaque. Periodontal disease results from the interaction of the host with bacterial products, and T-cell-derived cytokines remain critical in the immunoregulation of periodontal disease. METHODS: The aim of this study was to examine the role of T helper type 1 [interleukin-12p40 (IL-12p40), interferon-gamma, tumour necrosis factor (TNF)] and type 2 (IL-4, IL-10) cytokines in the immune response to a subcutaneous challenge with P. gingivalis using a well-established murine abscess model, in genetically modified cytokine-specific knockout mice. RESULTS: IL-12p40(-/-) mice exhibited more advanced tissue destruction and a reduced inflammatory cell infiltrate after subcutaneous P. gingivalis challenge. Deficiency of IL-4 or IL-10 did not result in increased susceptibility to P. gingivalis-mediated tissue destruction. Furthermore, TNF deficiency appeared to reduce local tissue destruction. Interestingly, serum-specific antibodies suggested a strong T helper type 2 response. CONCLUSION: The results of our study indicate an important role for IL-12 in a primary P. gingivalis subcutaneous challenge.     

Effect of arylhydroxylamine metabolites of sulfamethoxazole and dapsone on stress signal expression in human keratinocytes

The initiation of an immune response to small molecules is believed to require the release of stress/danger signals that activate resident dendritic cells, presumably secondary to the formation of reactive metabolites. We hypothesized that exposure to arylhydroxylamine metabolites of dapsone and sulfamethoxazole lead to the expression/release of numerous stress signals in the skin. To test this hypothesis, we examined the effect of these metabolites on the expression of selected heat shock proteins, uric acid, cytokines, adhesion molecules, and costimulatory molecules in normal human epidermal keratinocytes (NHEKs). NHEKs showed a time-dependent up-regulation of heat shock protein 70 and translocation of heat shock protein 27 when exposed to the arylhydroxylamine metabolites. In addition, the secretion of several proinflammatory cytokines was increased upon incubation of these cells with metabolite. In contrast, the uric acid concentration was not altered. Moreover, intercellular adhesion molecule-1, CD80, and CD86 expressions did not change when NHEKs were exposed to these reactive metabolites. Our data suggest that NHEKs selectively up-regulate certain danger signals when exposed to arylhydroxylamine metabolites. These signals may subsequently activate dendritic cells and initiate an immune response within skin.     

A Comparison between iPad-Assisted and Teacher-Directed Reading Instruction for Students with Autism Spectrum Disorder (ASD)

We conducted an alternating treatment research design to investigate the effects of a multicomponent reading comprehension intervention on reading comprehension performance and task refusal behavior of three elementary students with autism spectrum disorder (ASD). This study also sought to investigate the effects of utilizing teacher-directed instruction (TDI) in comparison to iPad® -assisted instruction (IAI) as the primary mode of instructional delivery during reading sessions. The multicomponent intervention during the TDI sessions consisted of teaching text preview strategy (i.e., looking at text and picture, making predictions), identifying the main idea of each paragraph using a graphic organizer, and the use of a token economy system. Whereas IAI treatment sessions consisted of the use of an iPad® application that focused on identifying main idea paired with implementing a token economy system for task completion. Three elementary students identified with ASD participated in this study. Results indicate that the multicomponent intervention implemented during both conditions was associated with improved performance on curriculum-based measure (CBM) probes during TDI and IAI treatments, with an indication that the TDI treatment was more effective in increasing accuracy of responding on CBM probes in comparison to the IAI condition. Findings from this study also indicate that both treatment conditions (TDI and IAI) were associated with a reduction of task refusal for the three participants with fewer occurrences of the challenging behavior during IAI in comparison to TDI treatment.     

United Kingdom Survey of Culture-Negative Peritonitis and Dialysate Sampling Practice

Peritonitis is a major cause of technique failure in peritoneal dialysis (PD) and accurate diagnosis ensures successful management and avoids unnecessary antibiotic exposure. United Kingdom (UK) registry data on peritonitis rates are not routinely reported. We conducted an electronic survey amongst senior PD nurses and microbiologists to obtain information about PD effluent sampling and processing practices in the UK. The survey was completed by 53 of 79 centres (67% response rate). The median annual culture-negative rate was 15% (range 5 – 38%). The main findings were wide variation in reported sampling volumes and processing methods that may in part explain the variation in culture-negative rates. Adherence to guidelines might reduce culture-negative rates informed by reporting data into national registries.Peritonitis is a major cause of technique failure in peritoneal dialysis (PD), and accurate diagnosis ensures successful management and avoids unnecessary antibiotic exposure. International guidelines recommend PD centers aim for culture-negative peritonitis rates of < 20% per year and suggest < 10% is achievable in centers of excellence (1). The most accurate and cost-effective way of achieving this is not known, and United Kingdom (UK) registry data on peritonitis rates are not routinely reported. We aimed to obtain information about PD effluent sampling and processing practices in the UK.     

Unexpected Positive Intraoperative Cultures in Aseptic Revision Arthroplasty

Unexpected positive intraoperative cultures (UPIC) in presumed aseptic revision arthroplasty can be difficult to interpret. The purpose of this retrospective study was to compare the incidence of subsequent periprosthetic joint infection (PJI) in patients who received antibiotic therapy according to an institutional protocol with those who did not and whether they meet Musculoskeletal Infection Society (MSIS) criteria for PJI. In patients who were treated with antibiotic according to institutional criteria, the incidence of PJI after revision was higher in those who did not meet MSIS criteria (22%) than in those that met MSIS criteria (14%; P > 0.71). UPIC in aseptic revision arthroplasty are not uncommon. PJI cannot be excluded in patients that do not meet MSIS definition.     

Dietary,Lifestyle and Socio-Economic Correlates of Overweight,Obesity and Central Adiposity in Lebanese Children and Adolescents

The Eastern Mediterranean region is characterized by one of the highest burdens of paediatric obesity worldwide. This study aims at examining dietary, lifestyle, and socio-economic correlates of overweight, obesity, and abdominal adiposity amongst children and adolescents in Lebanon, a country of the Eastern Mediterranean basin. A nationally representative cross-sectional survey was conducted on 6–19-year-old subjects (n = 868). Socio-demographic, lifestyle, dietary, and anthropometric data (weight, height, waist circumference) were collected. Overweight and obesity were defined based on BMI z-scores. Elevated waist circumference (WC) and elevated waist to height ratio (WHtR) were used as indices of abdominal obesity. Of the study sample, 34.8% were overweight, 13.2% were obese, 14.0% had elevated WC, and 21.3% had elevated WHtR. Multivariate logistic regression analyses showed that male gender, maternal employment, residence in the capital Beirut, sedentarity, and higher consumption of fast food and sugar sweetened beverages were associated with increased risk of obesity, overweight, and abdominal adiposity, while regular breakfast consumption, higher intakes of milk/dairies and added fats/oils were amongst the factors associated with decreased risk. The study’s findings call for culture-specific intervention strategies for the promotion of physical activity, healthy lifestyle, and dietary practices amongst Lebanese children and adolescents.     

Two new compounds from the aerial parts of Bergenia himalaica Boriss and their anti-hyperglycemic effect in streptozotocin-nicotinamide induced diabetic rats

Ethnopharmacological relevance

Bergenia himalaica Boriss is mainly distributed in the temperate Himalayas between altitudes of 900 and 3000 m ranging from the southeastern regions in central Asia and northern regions in South Asia. The plant has a long history of its use in traditional medicine for the treatment of various diseases such as diabetes, urinary complaints, kidney stones, hemorrhagic diseases and epilepsy. The aim of this study is to isolate pure compounds from Bergenia himalaica Boriss, elucidate their structures and determine their blood glucose lowering activity to obtain additional scientific evidence for its usage in traditional medicine for the management of diabetes.

Materials and methods

The crude methanolic extract from the aerial parts of Bergenia himalaica Boriss was separated into EtOAc and water sub-extracts and the EtOAc sub-extract was further divided into petroleum ether soluble and insoluble fractions. The pet-ether insoluble fraction was subjected to fractionation through column chromatography followed by prep. TLC. The blood glucose lowering activity of the 2 new compounds was evaluated in streptozotocin–nicotinamide induced diabetic rats. Additionally, glucose-stimulated insulin secretion was measured on isolated mice islets.

Results

Two new compounds bergenicin and bergelin were isolated and their structures determined on the basis of spectral analysis. Significant decrease of blood glucose was observed at 1-h (1.0 mg/kg) and 2-h (0.5 mg/kg), after bergenicin administration to the diabetic rats and at 2-h (1.0 mg/kg) and 3-h (0.5 mg/kg), after bergelin administration. Bergenicin, but not bergelin, enhanced glucose-stimulated insulin secretion in isolated pancreatic islets.

Conclusions

In the present studies two new compounds, bergenicin and bergelin were isolated from Bergenia himalaica Boriss and their structures were elucidated. Both the compounds showed anti-hyperglycemic effects in streptozotocin–nicotinamide induced diabetic rats. Bergenicin showed insulinotropic effect; suggesting that the anti-hyperglycemic effect is mostly due to enhancement of insulin secretion from pancreatic β-cells.     

Tanning and skin cancer

Skin cancer is a large and growing problem in the United States. Sun and other ultraviolet (UV) light exposures play a key role in the development of skin cancer. Pediatricians can play an important role in counseling patients and are in a position to help educate children and their families about skin cancer. The purpose of this review is to familiarize pediatricians with the magnitude of the skin cancer problem and the evidence that ultraviolet light exposure, particularly indoor tanning, contributes to this problem. We reviewed the literature on ultraviolet light and skin cancer (based on a MEDLINE search of articles using the headings "ultraviolet light" and "skin cancer") and found that skin cancer is the most rapidly growing cause of cancer deaths in the United State. There is strong epidemiologic evidence for the relationship between UV exposure and nonmelanoma skin cancer and growing evidence for the relationship between indoor tanning and melanoma. We recommend that pediatricians counsel children and their parents about UV protection. Measures such as use of sunscreen and hats for outdoor play, both at home and in school, should be encouraged.