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Mini-implant supported canine retraction with micro-osteoperforation: A split-mouth randomized clinical trial
Get PDFObjectives: To investigate, using a split-mouth randomized clinical design, the effect of micro-osteoperforation (MOP) on mini-implant supported canine retraction using fixed appliances. Materials and Methods: Thirty subjects (seven males and 23 females) with a mean age of 22.2 (3.72) years were randomized into three canine retraction groups: Group 1 (MOP 4-weekly maxilla/ 8-weekly mandible; n = 10); Group 2 (MOP 8-weekly maxilla/12-weekly mandible; n = 10) and Group 3 (MOP 12-weekly maxilla/4-weekly mandible; n = 10) measured at 4-week intervals over 16 weeks. Subjects also completed pain (5-point Likert scale) and pain impact (Visual Analogue Scale) questionnaires. The primary outcome was the amount of canine retraction over 16 weeks at MOP (experimental) and non-MOP (control) sites. Results: Mean overall canine retraction was 4.16 (1.62) mm with MOP and 3.06 (1.64) mm without. After adjusting for differences between jaws, all MOP groups exhibited significantly higher canine distalization than the control group: 0.89 mm more (95% confidence interval [CI] = 0.19 to 1.59 mm; P =.01) in the MOP-4 group, 1.08 mm more (95% CI = 0.49 to 1.68 mm; P =.001) in the MOP-8 group and 1.33 mm more (95% CI = 0.55 to 2.10 mm; P =.002) in the MOP-12 group. All subjects reported pain associated with MOP with 60% classifying it as moderate and 15% severe. The main impact of this reported pain was related to chewing and speech. Conclusions: MOP can increase overall mini-implant supported canine retraction over a 16-week period of observation but this difference is unlikely to be clinically significant. © 2019 by The EH Angle Education and Research Foundation, Inc
An in vitro Three-Dimensional Co-Culture System for Ameloblastoma Modelling (Sistem Ko-Kultur Tiga Dimensi secara in vitro untuk Pemodelan Ameloblastoma)
Get PDFAmeloblastoma, the most clinically significant odontogenic epithelial tumor, is a locally-invasive and destructive lesion in the jawbones. However, the nature of this infiltrativeness and destructive behavior remains ill-understood. To address this, we established an in vitro three-dimensional (3D) co-culture system to simulate an amelobastoma disease model aimed at investigating the interactions between tumor cells and osteoblasts. Osteoblastic cell lines (KUSA/A1 and mc3T3-E1) and one stromal cell line (ST2) were separately co-seeded with ameloblastoma-derived cell line (AM-1) in a collagen scaffold (representing the extracellular bone matrix) and incubated with mineralization medium. Inununohistochemistry, double immunofluorescence and mineralization assay were performed. Only Am-1/KUsA-A1 co-culture showed a significant increase in Am-1 cell count, suggesting that heterotypic cell-cell interaction promotes tumoral cell growth, while formation of visible Am-1 epithelial nest-like structures resembling ameloblastoma cells in their native state, suggest morphodffferentiation. A RANK-high, RANKL-low and osteoprotegerin-low immunoprofile in co-culture AM-1 cells implies deregulated osteoclastogenesis. Mineralization assays showed diminished calcification in Am-1/KUSA-A1 co-culture extracellular matrix suggesting an altered local bone metabolism. In contrast, KUSA/A1 monocultures showed abundant extracellular matrix calcification. Taken together, these results suggest that a 3D co-culture system as an amelobastoma disease model provides insights that bidirectional ameloblastoma-osteoblastic interactions might play a role in modulating tumor growth and osteoclastogenesis
Comprehensive functional profiling of long non-coding RNAs through a novel pan-cancer integration approach and modular analysis of their protein-coding gene association networks
Get PDFBackground: Long non-coding RNAs (lncRNAs) are emerging as crucial regulators of cellular processes in diseases such as cancer, although the functions of most remain poorly understood. To address this, here we apply a novel strategy to integrate gene expression profiles across 32 cancer types, and cluster human lncRNAs based on their pan-cancer protein-coding gene associations. By doing so, we derive 16 lncRNA modules whose unique properties allow simultaneous inference of function, disease specificity and regulation for over 800 lncRNAs. Results: Remarkably, modules could be grouped into just four functional themes: transcription regulation, immunological, extracellular, and neurological, with module generation frequently driven by lncRNA tissue specificity. Notably, three modules associated with the extracellular matrix represented potential networks of lncRNAs regulating key events in tumour progression. These included a tumour-specific signature of 33 lncRNAs that may play a role in inducing epithelial-mesenchymal transition through modulation of TGFβ signalling, and two stromal-specific modules comprising 26 lncRNAs linked to a tumour suppressive microenvironment and 12 lncRNAs related to cancer-associated fibroblasts. One member of the 12-lncRNA signature was experimentally supported by siRNA knockdown, which resulted in attenuated differentiation of quiescent fibroblasts to a cancer-associated phenotype. Conclusions: Overall, the study provides a unique pan-cancer perspective on the lncRNA functional landscape, acting as a global source of novel hypotheses on lncRNA contribution to tumour progression. © 2019 The Author(s)
A New Small Satellite Sunspot Triggering Recurrent Standard and Blowout Coronal Jets
No full textIn this paper, we report a detailed analysis of recurrent jets originated from a location with emerging, canceling, and converging negative magnetic field at the east edge of NOAA active region AR11166 from 2011 March 9 to 10. The event presented several interesting features. First, a satellite sunspot appeared and collided with a pre-existing opposite polarity magnetic field and caused a recurrent solar jet event. Second, the evolution of the jets showed blowout-like nature and standard characteristics. Third, the satellite sunspot exhibited a motion toward the southeast of AR11166 and merged with the emerging flux near the opposite polarity sunspot penumbra, which afterward, due to flux convergence and cancellation episodes, caused recurrent jets. Fourth, three of the blowout jets associated with coronal mass ejections (CMEs), were observed from the field of view of the Solar Terrestrial Relations Observatory. Fifth, almost all the blowout jet eruptions were accompanied with flares or with more intense brightening in the jet base region, while almost standard jets did not manifest such obvious features during eruptions. The most important feature, the blowout jets, were inclined to faster and larger scales than the standard jets. The standard jets instead were inclined to be relatively longer-lasting. The obvious shearing and twisting motions of the magnetic field may be interpreted as due to the shearing and twisting motions for a blowout jet eruption. The statistical results show that ∼30% of the blowout jets directly developed into CMEs. This suggests that the blowout jets and CMEs should have a close relationship. © 2019. The American Astronomical Society. All rights reserved
Soret and Dufour effects on doubly diffusive convection of nanofluid over a wedge in the presence of thermal radiation and suction
No full textThis paper investigates the effects of thermal radiation, Dufour, and Soret effects on doubly diffusive convective heat transfer of nanoliquid over a wedge in the presence of wall suction. The governing equations are transformed to nonlinear ordinary differential equations using similarity transformation. The resulting system is solved numerically by the fourth-order Runge-Kutta-Gill method with a shooting technique and a Newton-Raphson method. The solutions are expressed in terms of velocity, temperature, solutal concentration, and volume fraction profiles. The effects of pertinent parameters involved in the problem such as wedge angle, thermal radiation, Brownian motion, thermophoresis, Soret number, and Dufour number on the skin friction coefficient, local Nusselt number, and local Sherwood number are discussed in detail. © 2019 Sharif University of Technology. All rights reserved
Awareness of lifestyle-related cancer risk factors and health promoting behaviours among nurses in Malaysia
No full textAims and objectives: To assess the awareness of lifestyle-related cancer risk factors and health-promoting behaviors among nurses in Malaysia.
Background: The essence of nursing is caring. Nurses are known for taking care of others at the cost of their own health. Lack of self-care among nurses can lead to compassion fatigue, errors on the job, personal health problems and general disdain for life. The nurses' self-care starts with the awareness of modifiable health risk factors and their behaviors in promoting health.
Design: A descriptive cross-sectional design.
Methods: A total of 357 participants completed the questionnaire in a tertiary referral hospital. The awareness of cancer risk factors was measured based on twenty-nine established lifestyle factors. The health-promoting behaviors were evaluated by the Health-Promoting Lifestyle Profile II.
Results: Almost half of the participants are overweight and obese. Awareness among the six clearly established lifestyle-related cancer risk factors showed alcohol gamering the highest number of participants, followed by cured meats, overweight, high red meat diets, low vegetables, and fruit diets, and insufficient physical activity. 37.7% and 47.4% of the participants reported low and moderate levels of health-promoting behavior respectively. The highest mean score reported in the spiritual growth subscale and the lowest in the physical activity subscale.
Conclusion: Lifestyle-related cancer risk factors such as overweight, high red meat diets, low vegetables/fruit diets, and insufficient physical activity were not prioritized by the nurses. Although almost half of the nurses reported moderate levels of health-promoting behavior, it is worth noting that the nurses reported of the physical activity subscale to be the least.
Relevance to clinical practice: The findings have provided a useful insight into the current health behaviors of nurses and may serve well as an important indicator as to where education and supportive services should target their focus
Reactive oxygen species scavenging enzyme activities in berangan banana plant infected by Fusarium oxysporum f. sp. cubense
No full textFusarium oxysporum f. sp. cubense (FOC), a hemibiotrophic soil-borne pathogen is responsible for the most dreadful disease for banana plants worldwide. It is crucial to study the defense mechanism of banana plants against this disease in order to facilitate studies on future solutions. Increasing levels of reactive oxygen species (ROS) such as superoxide anions (O·2), hydrogen peroxide (H2O2), hydroxyl radicals (•OH) were among the earliest responses observed in banana plants following invasion by the offending pathogen and play an essential role in plant defense system. In order to have a more complete view of the berangan banana plant enzymatic antioxidant system, superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), peroxidase (POD), ascorbate peroxidase (APX), and glutathione reductase (GR) were analyzed in different parts of the plants: Roots, pseudostems and leaves. We observed a biphasic change in the ROS level and enzymatic activities in the infected plants. The ROS increased throughout the infection period while enzyme activities increased at the early stages of infection then decreased at later stages. The decline in the enzyme activities and the continuous increment in ROS at the later stages allow FOC to grow, thus increasing infection and eventually leading to necrosis. This suggests that these enzymes play an important role in berangan plant defense against FOC infection. © 2019, Chiang Mai University. All right reserved
How important is aerial leaf litter for insectivorous birds foraging in a Malaysian tropical forest?
No full textAerial leaf litter is a vital resource for insectivorous birds in tropical forests, particularly those that rely on dietary litter-dependent arthropods. The present study quantified and determined aerial-leaf litter selection patterns of specialist and regular dead-leaf users. In total, 486 observation sessions were conducted in a lowland tropical forest from February 2014 to September 2015. At least two ‘specialist’ species (over 75% of the observations) and seven ‘regular users’ species (25–74% of the observations) were found foraging for arthropods among aerial curled dead leaves within the aboveground vertical vegetation layers. These species belonged to four genera of the family Timaliidae and Pellorneidae: Cyanoderma, Stachyris, Pellorneum, and Malacopteron. The chestnut-winged babbler (Cyanoderma erythropterum) and the black-throated babbler (Stachyris nigricollis) were two species that heavily exploited the aerial leaf litter, accounting for 89% and 76% of the observations, respectively. The present study indicates that aerial leaf litter could serve as a vital foraging resource for most gleaning forest babblers in Malaysian rainforests. Moreover, niche separation among these dead-leaf foragers occurred due to their differing vertical strata preferences. The variations in body and bill sizes among the studied species suggest that they consume various arthropod sizes and taxonomic groups. A morphological analysis identified Hymenoptera, Coleoptera, and Arachnida as the dominant litter-dependent arthropods, and a molecular analysis revealed the presence of additional insect groups in the aerial leaf litter (e.g. Diptera and Lepidoptera). This study highlights the importance of maintaining undergrowth vegetation that can intercept aerial leaf litter to provide important foraging opportunities for forest bird species. © 201
Resistance element welding of magnesium alloy and austenitic stainless steel in three-sheet configurations
No full textThe Mg alloy and two austenitic stainless steel sheets were joined together by a metallurgical bond across the rivet and two austenitic stainless steel sheets. More heat was generated at the austenitic stainless/austenitic stainless interface than at the rivet/ austenitic stainless steel interface, leading to larger nugget size at the austenitic stainless steel /austenitic stainless steel interface at all welding currents. Thus, the nugget size at the austenitic stainless steel /austenitic stainless steel interface mainly influenced the transition from interfacial to pullout failure modes. The fusion zone microstructure consisted of ferrite and austenite. The microstructure in the edges of the nugget (both in the rivet and ASS) consisted of fine columnar dendritic grains. Owing to variation of temperature gradient and solidification growth rate, the grains morphology changed from columnar dendritic to equiaxed dendritic in the nugget center. The fine grains resulted in high fusion zone hardness. Digital image correlation analysis revealed that the joints could experience joining zone rotation/out-of-plane displacement during lap-shear tests, which reduced the magnitude of strain sustained by the joints in the loading direction. The joint configuration that did not undergo joining zone rotation and failed via pullout failure in the austenitic stainless steel sheet exhibited superior lap-shear performance. © 201