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In orthodontic applications, NiTi wires are under continuous bending stress and exposed to fluctuations in temperature over long durations. The sensitivity of NiTi to temperature can have a considerable influence on its mechanical properties. This study investigated the effects of deflected NiTi wire, presented in stress-induced (detwinned) martensite microstructure, combined with thermal cycle on the microstructure and mechanical properties.We tested four types of as-received orthodontic NiTi: (1) Nitinol Classic (3 M Unitek), (2) Sentalloy (Tomy), (3) 27 °C CuNiTi (Ormco) and (4) 40 °C CuNiTi (Ormco). Each group of specimens was subjected to three different testing conditions: (1) temperature fluctuations (5000 cycles) between 5 and 55 °C, (2) continuous three-point bending force and (3) combination of thermal cycling and bending stress.The specimens that underwent thermocycling as well as loading exhibited a substantial narrowing in stress hysteresis, which may be attributed to crystallinity lower than that of as-received NiTi wires. Reduced crystallinity can manifest in a number of imperfections, such as dislocations and internal stress, as well as a less-organized structure. Micro X-ray diffraction (XRD) analysis revealed the existence of martensite phase in Sentalloy wires subject to thermal and stress conditions. Under loading conditions, stress-induced martensite of NiTi wires exposed to temperature fluctuations of 5-55 °C also induced cyclic changes in bending stress. In a simulated intra-oral environment, the stability of austenite↔martensite transformation decreased.This study determined that bending stress in conjunction with repeated temperature fluctuations can greatly affect the microstructure and mechanical properties of NiTi wires.

Objective Pregnancy and menopause are significant life events associated with major changes in female hormone levels and changes in cardiovascular health. The role of estrogen in influencing cardiovascular risk is an ongoing research topic. Many studies have provided evidence that radial pressure wave characteristics are an important indicator to consistently and independently predict cardiovascular events. The aim of this study was to investigate if radial pressure wave analysis provided statistical insights into the physiological variations due to pregnancy and menopause. Furthermore, the study investigated how these variations could serve as an indicator for cardiovascular risks. As the radial pulse measurement is non-invasive and speedy, it may be helpful in evaluating cardiovascular changes and risk during these transitions. Materials and method A total of 702 randomly selected female subjects (90 pregnant and 97 post-menopausal), aged 20–59, enrolled in the study. The visit measured the subject's hemodynamic parameters including heart rate, systolic blood pressure (SBP), diastolic blood pressure (DBP) and radial pressure waves. SBP and DBP were evaluated by an automatic blood pressure monitor. Radial pressure wave data were continuously recorded for 12-s using a TD01C pulse measuring instrument. Spectrum analysis of the radial pressure wave was performed to evaluate the first five harmonic components (C1–C5). Results A comparison of pregnant women to non-pregnant women showed C3 and C5 were lower. Heart rate C2 and C4 were higher in pregnant women. A comparison of women pre-menopausal and post-menopausal showed no significant difference in SBP or DBP. Menopause significantly changed the C1 and C4 radial pressure wave harmonics. An increase in C1 and a decrease in C4 were observed. Conclusion and discussion This study provided further clinical evidence to support the hemodynamic model that describes the cardiovascular changes and risks related to the harmonic components of the pulse spectrum. Beyond blood pressure, the effects of menopause on the radial pressure wave, especially on hemodynamic index C4, independent of age and BMI, may explain increased post-menopausal cardiovascular risk. This and past studies collectively suggest that radial pressure wave components may be an indicator of a female body's ability to supply oxygen and nutrients. Harmonic analysis of the radial pressure wave may provide additional insights into the underlying mechanism of the cardiovascular changes over the lifespan of a woman.

Radiation-induced skin injury (RSI) is a frequent complication of radiotherapy. Severe cases affect the patient’s disease treatment and quality of life. The main purpose of this study is to examine the causative role of egg-yolk oil (EYO) in delayed radiation-induced skin injury, including impaired wound healing. Using polyvinyl pyrrolidone (PVP)-gelatin-chitosan (PGC) composite film as controlled release of egg-yolk oil (EYO) was studied in rats, which were used as a radiation-induced skin injury model. Different composition ratios were tested for their mechanical properties, moisture content, and degradation characteristics. The results showed that the PGC112 (w/w) substrate, which will hence be referred to as PGC, had the better properties. Further, the PGC was mixed with EYO (0.25% and 0.5%) to prepare the films (PGC/0.25EYO and PGC/0.5EYO, respectively). Furthermore, the mechanical and degradation properties and biocompatibility showed better results with PGC/0.5EYO. In animal studies, rats were irradiated with single-dose electron beams of 40 Gy. The animals were divided into five groups to perform wound treatment with various types of wound dressing for 30 days. Histological examination and CD68 immunochemical staining were then conducted, and observations were made. The results showed that PGC/0.5EYO has a significantly healing effects on radiodermatitis and good re-epithelialization.

Background Women not only have worse diabetes complications, but also have menstrual cycle, pregnancy, and menopause which can make managing diabetes more difficult. The aim of this study was to investigate if radial pressure wave analysis may non-invasively screen for women’s risk of type 2 diabetes. Methods Spectrum analysis of the radial pressure wave was performed to evaluate the first five harmonic components, C1 to C5. The study consisted of a total of 808 non-pregnant female subjects aged 20–95 over the period of 4 years, and 404 of them were diagnosed with Type 2 diabetes as the case group. Result The first five harmonic components are significantly different in a comparison of the case group and the control group. In the logistic regression analysis, T2DM was found to be associated with C1 (OR = 1.055, CI = 1.037–1.074, p < 0.001), C2 (OR = 1.051, CI = 1.019–1.085, p = 0.002), and C3 (OR = 0.972, CI = 0.950–0.994, p = 0.013). In the Receiver Operating Characteristic curve analysis, the Area Under Curve of using C3 only (70%, p Conclusion We thus concluded that pulse spectrum was a non-invasive predictor for women’s risk of T2DM.

Orthognathic surgical planning compromises three clinical needs: occlusal balancing, symmetry, and harmony, which may result in multiple outcomes. Facial symmetry is the ultimate goal for patients and practitioners. Pure virtual planning and mixed reality planning were two innovative technologies in clinical practices compared to conventional model surgery used for decades. We proposed quantitative asymmetry assessment methods in both mandibular contour (in 2D) and a midface and mandible relationship in 3D. A computerized optimal symmetry plane, being the median plane, was applied in both planning methods. In the 3D asymmetry assessment between two planning methods, the deviation angle and deviation distance between midface and mandible were within 2° and 1.5 mm, respectively. There was no significant difference, except the symmetry index of the anterior deviation angle between the virtual and mixed reality planning in the 3D asymmetry assessment. In the mandible contour assessment, there was no significant difference between the virtual and mixed reality planning in asymmetry assessment in the frontal and frontal downward inclined views. Quantitative outcomes in 3D asymmetry indices showed that mixed reality planning was slightly more symmetric than virtual planning, with the opposite in 2D contouring.

This study aimed to investigate the time trend variation in the surgical volume and prognostic outcome of patients with lung cancer after the gradual prolonged implementation of a low-dose computed tomography (LDCT) lung cancer screening program.Using the hospital-based cancer registry data on number of patients with lung cancer and deaths from 2008 to 2017, we conducted a retrospective study using a hospital-based cohort to investigate the relationship between changes in lung cancer surgical volume, the proportion of lung-sparing surgery, and prolonged prognostic outcomes after the gradual implementation of the LDCT lung cancer screening program in recent years.From 2008 to 2017, 3251 patients were diagnosed with lung cancer according to the hospital-based cancer registry. The 5-year mortality rate decreased gradually from 83.54% to 69.44% between 2008 and 2017. The volume of total lung cancer surgical procedures and proportion of lung-sparing surgery performed gradually increased significantly from 2008 to 2017, especially from 2014 to 2017 after implementation of a large volume of LDCT lung cancer screening examinations. In conclusion, our real-world data suggest that there will be an increase in cases of operable early-stage lung cancers, which in turn will increase the surgical volume and proportion of lung-sparing surgery, after the gradual implementation of the LDCT lung cancer screening program in recent years. These findings suggest the importance of a successful national policy regarding LDCT screening programs, regulation of shortage of thoracic surgeons, thoracic radiologist workforce training positions, and education programs.

Considerable attention has been focused on long‐term use of proton pump inhibitor (PPI) medications in relation to increased risk of cancer via stimulation of DNA‐damaged cells. The aim of this study is to examine the dose‐dependent effect of PPI on periampullary cancers in a national population‐based cohort. A nested case–control analysis was constructed based on Taiwan's National Health Insurance Research Database and the Taiwan Cancer Registry between the years 2000 and 2010. Cases involving patients diagnosed with periampullary cancers were selected and controls were matched to cases according to age, sex and observational period. A “PPI user” was defined as any patient receiving more than 28 cumulative defined daily doses as measured by prescription drug claims. Conditional logistic regression analysis was conducted to calculate odds ratios (ORs) and 95% confidence intervals (CIs) according to the level of PPI exposure. A total of 7,681 cases and 76,762 matched controls were included with a mean follow‐up period of 6.6 years (SD: 2.0). The odds of PPI exposure in patients with periampullary cancers were higher than that of control patients with an adjusted OR of 1.35 (95% CIs: 1.16–1.57). Our results also showed that PPI exposure was slightly linked to periampullary cancers in dose‐dependent manner. A similar association was observed in patients who solely took PPI but no eradication therapy for Helicobacter pylori infection. Long‐term PPI use was associated with an increased risk of periampullary cancers in the current population‐based study. Physicians must weigh potential risks of long‐term maintenance against therapeutic benefit., What's new? Proton pump inhibitor (PPI) medications are a common treatment for gastroesophageal reflux disease and peptic ulcer disease. However, some evidence indicates that long‐term use of PPIs might increase cancer risk. This large Taiwanese study found that PPI exposure was indeed slightly linked to an increased risk of periampullary cancers, in a dose‐dependent manner. (This was not seen in patients undergoing H. pylori eradication therapy, however.) These results indicate that physicians must weigh the potential risks of long‐term maintenance use of PPIs against their therapeutic benefit.

Though the compromised blood-brain barrier (BBB) is a pathological hallmark of Japanese encephalitis-associated neurological sequelae, the underlying mechanisms and the specific cell types involved are not understood. BBB characteristics are induced and maintained by cross talk between brain microvascular endothelial cells and neighboring elements of the neurovascular unit. In this study, we show a potential mechanism of disruption of endothelial barrier integrity during the course of Japanese encephalitis virus (JEV) infection through the activation of neighboring pericytes. We found that cultured brain pericytes were susceptible to JEV infection but were without signs of remarkable cytotoxicity. JEV-infected pericytes were found to release biologically active molecules which activated ubiquitin proteasome, degraded zonula occludens-1 (ZO-1), and disrupted endothelial barrier integrity in cultured brain microvascular endothelial cells. Infection of pericytes with JEV was found to elicit elevated production of interleukin-6 (IL-6), which contributed to the aforementioned endothelial changes. We further demonstrated that ubiquitin-protein ligase E3 component n -recognin-1 (Ubr 1) was a key upstream regulator which caused proteasomal degradation of ZO-1 downstream of IL-6 signaling. During JEV central nervous system trafficking, endothelial cells rather than pericytes are directly exposed to cell-free viruses in the peripheral bloodstream. Therefore, the results of this study suggest that subsequent to primary infection of endothelial cells, JEV infection of pericytes might contribute to the initiation and/or augmentation of Japanese encephalitis-associated BBB breakdown in concerted action with other unidentified barrier disrupting factors.

OBJECTIVE: To investigate the effects of bracket bevel design and oral environmental factors (saliva, temperature) on frictional resistance. MATERIALS AND METHODS: Five types of brackets, namely a conventional bracket (Omni-arch), an active self-ligating bracket (Clippy), and three passive self-ligating brackets (Carriere, Damon, and Tenbrook T1) coupled with a 0.014-inch austenitic nickel-titanium archwire were tested. In the experimental model, which used a group of five identical brackets, the center bracket was displaced 3 mm to mimic the binding effects. The friction experiments were performed at three temperatures (20°C, 37°C, 55°C) in a dry or a wet (artificial saliva) state. Finally, the surfaces of the bracket slots were observed using scanning electron microscopy (SEM) before and after the friction tests. RESULTS: The sliding frictional force was significantly influenced by the bracket slot bevel and saliva whether in the active or passive configuration (P < .05). The frictional force significantly increased as the temperature increased in the active configuration (P < .01). Based on the SEM observations, a correlation was found among the level of frictional force, the bevel angle, and the depth of scratches on bracket bevels. CONCLUSION: Frictional force can be reduced by increasing the bevel angle and by lowering the oral temperature, whereas the presence of saliva increases frictional resistance.

This study attempted to accelerate the peripheral nerve regeneration, using the high outflow rate of asymmetric poly(dl-lactic acid-co-glycolic acid) (PLGA) nerve conduits. Asymmetric PLGA nerve conduits of monomer ratio 85/15 were prepared by immersion-precipitation method to serve as possible materials. In this study, mandrels were immersed into a 20% (wt/wt) of PLGA/1,4-dioxane solution and precipitated in a non-solvent bath followed by freeze-drying. Different concentrations of isopropyl alcohol (95%, 40% and 20%) were used as precipitation baths where non-asymmetric (95%) and asymmetric (40% and 20%) conduits could easily form. The asymmetric nerve conduits that consisted of macrovoids on the outer layer, and interconnected micropores in the inner sublayer, possessed characters of larger outflow rate than inflow rate. The asymmetric conduits were implanted to 10mm right sciatic nerve defects in rats. Autografts, silicone and non-asymmetric PLGA conduits were performed as the control and the contrast groups. Implanted graft specimens of all groups were harvested for histological analysis at 4 and 6 weeks following surgery. The asymmetric PLGA conduits maintained a stable supporting structure and inhibited exogenous cells invasion during entire regeneration process. Asymmetric PLGA conduits were found to have statistically greater number of regenerated axons at the midconduit and distal nerve site of implanted grafts, as compared to the silicone and non-asymmetric groups at 4 and 6 weeks. Of interest was that the results of 4 weeks in asymmetric groups were better than the non-asymmetric groups at 6 weeks in number of axons. According to the results of permeability, the asymmetric structure in the conduit wall seemed to enhance the removal of the blockage of the waste drain from the inner inflamed wound in the early stage, which may have improved the efficacy of the peripheral nerve regeneration. The asymmetric structure could be adequately employed in the future as optimal nerve conduits in peripheral nerve regeneration.

Currently, the underlying mechanisms and the specific cell types associated with Japanese encephalitis-associated leukocyte trafficking are not understood. Brain microvascular endothelial cells represent a functional barrier and could play key roles in leukocyte central nervous system trafficking. We found that cultured brain microvascular endothelial cells were susceptible to Japanese encephalitis virus (JEV) infection with limited amplification. This type of JEV infection had negligible effects on cell viability and barrier integrity. Instead, JEV-infected endothelial cells attracted more leukocytes adhesion onto surfaces and the supernatants promoted chemotaxis of leukocytes. Infection with JEV was found to elicit the elevated production of intercellular adhesion molecule-1, cytokine-induced neutrophil chemoattractant-1, and regulated-upon-activation normal T-cell expressed and secreted, contributing to the aforementioned leukocyte adhesion and chemotaxis. We further demonstrated that extracellular signal-regulated kinase was a key upstream regulator which stimulated extensive endothelial gene induction by up-regulating cytosolic phospholipase A₂, NF-κB, and cAMP response element-binding protein via signals involving phosphorylation. These data suggest that JEV infection could activate brain microvascular endothelial cells and modify their characteristics without compromising the barrier integrity, making them favorable for the recruitment and adhesion of circulating leukocytes, thereby together with other unidentified barrier-disrupting mechanisms contributing to Japanese encephalitis and associated neuroinflammation.