Opening and closure forces of sliding mechanisms of different self-ligating brackets

Self-ligating brackets engage the wire by means of a slide mechanism. Forces that have to be applied to open and close the sliding mechanism of brackets are still unknown. OBJECTIVE: The aim of this study was to measure and compare the opening and closure forces of different self-ligating brackets. MATERIAL AND METHODS: Three different stainless steel self-ligating brackets (Carriere LX, Ortho Organizers; F1000, Leone; Damon Q, Ormco) were tested. For each different bracket, 20 maxillary right central incisors and 20 mandibular right central incisors were used. Opening and closure forces were measured using an Instron Universal Testing Machine. Statistical analysis was performed and ANOVA and Tukey tests were carried out. RESULTS: Opening forces were registered between 1.1 N and 5.6 N, whereas closure forces were recorded between 1.57 N and 4.87 N. Significant differences were detected among the different brackets and between the two prescriptions tested. CONCLUSION: The knowledge of different opening and closure forces of self-ligating brackets can help the orthodontist in the clinical management of these devices

Molecular Identification of Atlantic Bluefin Tuna (Thunnus thynnus, Scombridae) Larvae and Development of a DNA Character-Based Identification Key for Mediterranean Scombrids

The Atlantic bluefin tuna, Thunnus thynnus, is a commercially important species that has been severely over-exploited in the recent past. Although the eastern Atlantic and Mediterranean stock is now showing signs of recovery, its current status remains very uncertain and as a consequence their recovery is dependent upon severe management informed by rigorous scientific research. Monitoring of early life history stages can inform decision makers about the health of the species based upon recruitment and survival rates. Misidentification of fish larvae and eggs can lead to inaccurate estimates of stock biomass and productivity which can trigger demands for increased quotas and unsound management conclusions. Herein we used a molecular approach employing mitochondrial and nuclear genes (CO1 and ITS1, respectively) to identify larvae (n = 188) collected from three spawning areas in the Mediterranean Sea by different institutions working with a regional fisheries management organization. Several techniques were used to analyze the genetic sequences (sequence alignments using search algorithms, neighbour joining trees, and a genetic character-based identification key) and an extensive comparison of the results is presented. During this process various inaccuracies in related publications and online databases were uncovered. Our results reveal important differences in the accuracy of the taxonomic identifications carried out by different ichthyoplanktologists following morphology- based methods. While less than half of larvae provided were bluefin tuna, other dominant taxa were bullet tuna (Auxis rochei), albacore (Thunnus alalunga) and little tunny (Euthynnus alletteratus). We advocate an expansion of expertise for a new generation of morphology-based taxonomists, increased dialogue between morphology-based and molecular taxonomists and increased scrutiny of public sequence databases.Versión del editor4,411

Identification of co-expression gene networks, regulatory genes and pathways for obesity based on adipose tissue RNA Sequencing in a porcine model

Background: Obesity is a complex metabolic condition in strong association with various diseases, like type 2 diabetes, resulting in major public health and economic implications. Obesity is the result of environmental and genetic factors and their interactions, including genome-wide genetic interactions. Identification of co-expressed and regulatory genes in RNA extracted from relevant tissues representing lean and obese individuals provides an entry point for the identification of genes and pathways of importance to the development of obesity. The pig, an omnivorous animal, is an excellent model for human obesity, offering the possibility to study in-depth organ-level transcriptomic regulations of obesity, unfeasible in humans. Our aim was to reveal adipose tissue co-expression networks, pathways and transcriptional regulations of obesity using RNA Sequencing based systems biology approaches in a porcine model. Methods: We selected 36 animals for RNA Sequencing from a previously created F2 pig population representing three extreme groups based on their predicted genetic risks for obesity. We applied Weighted Gene Co-expression Network Analysis (WGCNA) to detect clusters of highly co-expressed genes (modules). Additionally, regulator genes were detected using Lemon-Tree algorithms. Results: WGCNA revealed five modules which were strongly correlated with at least one obesity-related phenotype (correlations ranging from -0.54 to 0.72, P <0.001). Functional annotation identified pathways enlightening the association between obesity and other diseases, like osteoporosis (osteoclast differentiation, P = 1.4E(-7)), and immune-related complications (e. g. Natural killer cell mediated cytotoxity, P = 3.8E(-5); B cell receptor signaling pathway, P = 7.2E(-5)). Lemon-Tree identified three potential regulator genes, using confident scores, for the WGCNA module which was associated with osteoclast differentiation: CCR1, MSR1 and SI1 (probability scores respectively 95.30, 62.28, and 34.58). Moreover, detection of differentially connected genes identified various genes previously identified to be associated with obesity in humans and rodents, e.g. CSF1R and MARC2. Conclusions: To our knowledge, this is the first study to apply systems biology approaches using porcine adipose tissue RNA-Sequencing data in a genetically characterized porcine model for obesity. We revealed complex networks, pathways, candidate and regulatory genes related to obesity, confirming the complexity of obesity and its association with immune-related disorders and osteoporosis

Rapid reprogramming of epigenetic and transcriptional profiles in mammalian culture systems

BackgroundThe DNA methylation profile of mammalian cell lines differs from the primary tissue from which they were derived, exhibiting increasing divergence from the in vivo methylation profile with extended time in culture. Few studies have directly examined the initial epigenetic and transcriptional consequences of adaptation of primary mammalian cells to culture, and the potential mechanisms through which this epigenetic dysregulation occurs is unknown.ResultsWe demonstrate that adaptation of mouse embryonic fibroblast, MEFS, to cell culture results in a rapid reprogramming of epigenetic and transcriptional states. We observed global 5-hydroxymethylcytosine (5hmC) erasure within three days of culture initiation. Loss of genic 5hmC was independent of global 5-methylcytosine (5mC) levels and could be partially rescued by addition of Vitamin C. Significantly, 5hmC loss was not linked to concomitant changes in transcription. Discrete promoter-specific gains of 5mC were also observed within seven days of culture initiation. Against this background of global 5hmC loss we identified a handful of developmentally important genes that maintained their 5hmC profile in culture, including the imprinted loci Gnas and H19. Similar outcomes were identified in the adaption of CD4+ T-cells to culture.ConclusionsWe report a dramatic and novel consequence of adaptation of mammalian cells to culture in which global loss of 5hmC occurs; suggesting rapid concomitant loss of methylcytosine dioxygenase activity. The observed epigenetic and transcriptional re-programming occurs much earlier than previously assumed, and has significant implications for the use of cell lines as faithful mimics of in vivo epigenetic and physiological processes.We thank Professors Adrian Bird and Nicholas Hastie for their comments on our manuscript. JT and RO are funded by IMI-MARCAR (under grant agreement number (115001) (MARCAR project)). Work in RM's lab is supported by the MRC, IMI-MARCAR and the BBSRC. This work in RM's lab was also initially funded by the Breakthrough Breast Cancer charity. Work in MB's lab was supported by Linkoping University strategic research funding and the Ake Wibergs fund (3772738). Work in SP's lab is supported by the BBSRC.</p

EFFECTS OF WEIGHT LOSS AND WEIGHT MAINTENANCE ON APOB IN OVERWEIGHT AND OBESE ADULTS

Emily E. Grammer1, Joshua E. McGee2, Taylor T. Brown2, Marie C. Clunan2, Anna C. Huff2, Briceida G. Osborne2, Laura E. Matarese2, Walter J. Pories2, Joseph A. Houmard, FACSM2, Robert A. Carels2, Mark A. Sarzynski, FACSM3, Damon L. Swift1. 1University of Virginia, Charlottesville, VA. 2East Carolina University, Greenville, NC. 3University of South Carolina, Columbia, SC. BACKGROUND: Apolipoprotein B (ApoB) is a predictor of cardiovascular disease and may have higher prognostic value compared to traditional lipid risk factors. There is a lack of data on the effects clinically significant weight loss (CWL) (≥7%) on ApoB and how weight maintenance after weight loss alters ApoB. The purpose of this study was to examine the effect on ApoB concentrations after CWL and exercise level during weight maintenance in overweight and obese adults. METHODS: Thirty overweight and obese adults (age: 45.7 [10.7] yrs; BMI: 34.4 [3.4] kg/m2) underwent a 10-week weight-loss intervention followed by 18 weeks of weight maintenance. During the weight loss phase, participants completed a hypocaloric weight-loss program (OPTIFAST) and supervised aerobic exercise. Exercise began at 300 MET min/week and increased by 50 MET min weekly until 700 MET min/week was reached. Participants that achieved CWL were randomized to weight maintenance (WM-REC; 970 MET min/week) or physical activity (PA-REC; 550 MET min/week) groups. Nuclear magnetic resonance (NMR) of plasma was used to assess blood components at baseline, after weight loss, and at follow-up. RESULTS: During the weight loss phase, participants decreased mass (-8.5 kg, p=0.001) and BMI (-3.1 kg/m2, p=0.001). Participants also reduced ApoB (-11.6 mg/dL, p=0.001), low density lipoprotein (LDL) (-8.0 mg/dL, p=0.013), high density lipoprotein (HDL) (-3.2 mg/dL, p=0.013), and TG (-27.2 mg/dL, p=0.001) after weight loss. During the weight maintenance phase, increased ApoB (20.9 mg/dL, p=0.006) and HDL (11.4 mg/dL, p=0.0.003), while LDL and TG did not change (p\u3e0.05). There were no differences between groups in changes in ApoB (WM-REC: 17.0; PA-REC: 23.8 mg/dL), HDL (WM-REC: 9.0; PA-REC: 13.3 mg/dL), LDL (WM-REC: 11.4; PA-REC: 2.4 mg/dL), and TG (WM-REC: 13.4; PA-REC: 1.0 mg/dL) (all ps \u3e0.05) during weight maintenance. Moreover, ApoB was not correlated with body composition or fitness changes in either phase of the study (p\u3e0.05). CONCLUSIONS: ApoB concentrations decreased following weight loss and exercise in obese adults yet increased during weight maintenance. These results indicate that high levels of aerobic exercise did not prevent regression in ApoB after clinically significant weight loss. Future lifestyle-based interventions should investigate nutritional approaches to maintain improvements in ApoB during weight maintenance

Monitoring Spawning Activity in a Southern California Marine Protected Area Using Molecular Identification of Fish Eggs

In order to protect the diverse ecosystems of coastal California, a series of marine protected areas (MPAs) have been established. The ability of these MPAs to preserve and potentially enhance marine resources can only be assessed if these habitats are monitored through time. This study establishes a baseline for monitoring the spawning activity of fish in the MPAs adjacent to Scripps Institution of Oceanography (La Jolla, CA, USA) by sampling fish eggs from the plankton. Using vertical plankton net tows, 266 collections were made from the Scripps Pier between 23 August 2012 and 28 August 2014; a total of 21,269 eggs were obtained. Eggs were identified using DNA barcoding: the COI or 16S rRNA gene was amplified from individual eggs and sequenced. All eggs that were successfully sequenced could be identified from a database of molecular barcodes of California fish species, resulting in species-level identification of 13,249 eggs. Additionally, a surface transport model of coastal circulation driven by current maps from high frequency radar was used to construct probability maps that estimate spawning locations that gave rise to the collected eggs. These maps indicated that currents usually come from the north but water parcels tend to be retained within the MPA; eggs sampled at the Scripps Pier have a high probability of having been spawned within the MPA. The surface transport model also suggests that although larvae have a high probability of being retained within the MPA, there is also significant spillover into nearby areas outside the MPA. This study provides an important baseline for addressing the extent to which spawning patterns of coastal California species may be affected by future changes in the ocean environment

Serum leptin in disabled and non-disabled children in an Indian slum population.

OBJECTIVE: To assess the concentration of serum leptin in a population of malnourished children and to compare the leptin levels of disabled and non-disabled children in this population. DESIGN: Case-control study. SUBJECTS: Eighty-one children, comprising 41 children with mixed disabilities and 40 non-disabled controls, were selected from 425 children involved in a case-control study assessing the nutritional status of children with disabilities in an Indian slum population. METHODS: Leptin was measured in the serum samples and was compared with anthropometry (weight-for-age Z-scores (WAZ), height-for-age Z-scores (HAZ), weight-for-height Z-scores (WHZ), body mass index (BMI), mid-upper-arm circumference (MUAC), sub-scapular skinfold thickness and triceps skinfold thickness) and serum acute phase proteins. RESULTS: The children were very malnourished with WAZ=-2.07 (s.d. 1.15), HAZ=-2.15 (s.d. 1.85) and WHZ=-1.07 (s.d. 0.83). Leptin was extremely low in both the disabled (1.44 ng/ml; 95% confidence interval, CI, 1.23-1.69) and the non-disabled (1.19 ng/ml; 95% CI 1.04-1.35) children. There were no differences between the disabled and non-disabled groups as a whole but 15 children with neurological disabilities had significantly higher (P<0.05) serum leptin (1.65 ng/ml; 95% CI 1.29-2.06) than the non-disabled children. Girls (1.55 ng/ml; 95% CI 1.29-1.87) had significantly higher concentrations of leptin than boys (1.11 ng/ml; 95% CI 1.02-1.22; P=0.002). Leptin did not correlate with any biochemical or anthropometric measures. CONCLUSIONS: In this population, where malnutrition was common, serum leptin levels were very low and did not correlate with anthropometry. SPONSORSHIP: UK Department for International Development; Virgin Airways through the Great Ormond Street Hospital Trustees