Generation of Concentration Gradients by a Outer-Circumference-Driven On-Chip Mixer

The concentration control of reagents is an important factor in microfluidic devices for cell cultivation and chemical mixing, but it is difficult to realize owing to the characteristics of microfluidic devices. We developed a microfluidic device that can generate concentration gradients among multiple main chambers. Multiple main chambers are connected in parallel to the body channel via the neck channel. The main chamber is subjected to a volume change through a driving chamber that surrounds the main chamber, and agitation is performed on the basis of the inequality of flow caused by expansion or contraction. The neck channel is connected tangentially to the main chamber. When the main chamber expands or contracts, the flow in the main chamber is unequal, and a net vortex is generated. The liquid moving back and forth in the neck channel gradually absorbs the liquid in the body channel into the main chamber. As the concentration in the main chamber changes depending on the pressure applied to the driving chamber, we generated a concentration gradient by arranging chambers along the pressure gradient. This allowed for us to create an environment with different concentrations on a single microchip, which is expected to improve observation efficiency and save space.

Age Estimation using Aorta Image Analysis in the Thai Population

The current technology used in imaging has an increasing role in medical education. The concept of using an image analysis programme to help in estimating the age of the aorta, the largest artery, can be clearly seen to be of use, especially in establishing age changes for the identification of individuals. The purposes of the study were to investigate gross morphology, morphometric parameters, and the correlation between parameters with age of the aorta in human cadavers by using an image analysis programme. A total of 244 specimens were dissected from 4 locations of 61 human aortas from donour and autopsy cadavers with an age range of 20 to 90 years. The morphometric parameters included outer circumference, inner circumference, aortic diameter, and average thickness of all locations of the aorta. These were defined and measured by using the image analysis programme. The results of this study showed that the outer circumference (r=0.808-0.739), inner circumference (r=0.763-0.682), vertical diameter of the aorta (r=0.628-0.524) and horizontal diameter of the aorta (r=0.808-0.396) showed a significant correlation with age in all areas of the aorta. In the ascending aorta, the correlation between the outer circumference, horizontal diameter and age were higher than other variables and areas. The age equation established pertinent to the outer circumference (OC) in the ascending aorta was age = -61.648+ (1.141(OC)) with a standard error of ± 12.45 years. The age prediction equation for the horizontal diameter (HD) in the ascending aorta was age = -35.799+ (4.134(HD)) and a standard error of ± 12.43 years. In conclusion, knowledge of the structural changes associated with age can be used for age estimation in forensic anthropology.

Maternal high-fat diet promotes the expansion of abdominal aortic aneurysm in adult offspring by enhancing osteoclast-like macrophage differentiation through down-regulation of IRF8 expression

Background and objective Maternal high-fat diet (HFD) has been shown to modulate vascular function and remodeling in adult offspring. Here, we investigated the impact of maternal HFD on abdominal aortic aneurysm (AAA) formation. Methods and results Eight-week-old female wild-type mice (C57BL/6) were fed a HFD or normal diet (ND) one week prior to mating, and the diet was continued throughout gestation and lactation. In eight-week-old male offspring, AAA was induced with the application of 0.5 M calcium chloride (CaCl2) on the infrarenal aorta. Offspring of HFD-fed dams (O-HFD) showed a significant increase in maximum outer diameter of AAA at 1, 4 and 8 weeks after surgery compared with offspring of ND-fed dams (O-ND). The lengths of outer circumference assessed by histological analysis were increased in O-HFD (p<0.05). Likewise, female O-HFD showed a greater length of outer circumference than female O-ND (p<0.05). While the number of F4/80-positive cells at 1 wk after surgery was comparable in the O-HFD and O-ND, the percentage of MMP-9/F4/80 double-positive cells was significantly increased in O-HFD. Consistently, fluorescent image of abdominal aorta taken by IVIS at 1 wk after surgery revealed a 2-fold increase in MMP activity. Intriguingly, F4/80-positive cells in O-HFD showed a 2.5-fold increase in co-staining with tartrate-resistant acid phosphate (TRAP), typical marker of osteoclast-like macrophages which abundantly secrete proteases than classically activated macrophages, while the percentage of TNF-α/F4/80 double-positive cells was comparable in the two groups. Pharmacological inhibition of osteoclastogenesis by zoledronic acid (ZA) (100μg/kg) completely abolished the exaggerated AAA development in O-HFD to an extent similar to that in O-ND, while AAA development in O-ND mice did not change after ZA treatment. Furthermore, in vitro TNF-α-induced osteoclast differentiation of bone marrow-derived macrophages (BMDMs) showed a significantly higher number of TRAP-positive cells in O-HFD, accompanied by a significant increase in osteoclast-related genes expression. Western blotting analysis revealed that the expression of NFATc1, master regulator of osteoclastogenesis, was significantly higher in O-HFD than that in O-ND, and immunofluorescent imaging showed that nuclear translocation of NFATc1 upon TNF-α stimulation was significantly enhanced in O-HFD. We further examined the expression of IFN regulatory factor 8 (IRF8) which suppresses osteoclastogenesis by inhibiting the function and expression of NFATc1. IRF8 mRNA and nuclear protein expression levels were significantly lower in O-HFD than those in O-ND. Conclusion Our findings demonstrate that maternal HFD accelerates CaCl2-induced AAA expansion, accompanied by the exaggerated accumulation of osteoclast-like macrophages and augmented activity of MMPs. Inhibition of macrophages skewing toward osteoclast-like cells could be a potential therapeutic target for preventing AAA development. Funding Acknowledgement Type of funding source: None

DETERMINATION OF THE WORKING AREA OF THE EDGE SIEVE OF GRAIN CRUSHER WITH INCREASED SEPARATING SURFACE

Hammer crushers are widely used for the destruction of grain in feed preparation. When they work in the grinding chamber, as a result of the rotor’s rotation, air flows arise that involve particles of crushed material and whole grains in motion, thereby creating an air-productive layer. These air flows are influenced by the shape and geometrical parameters of the blades, their location, rotor diameter and speed, and the parameters of the separating surface. Under the conditions of Knyagininskiy University, a hammer crusher with an enlarged separating surface was developed, the working chamber of which was formed by two end and one peripheral sieves. Angle hammers, straight hammers, or a combination of straight hammers and corner blades placed between them were installed on the rotor as working units. The study was carried out to study the effect of the type of working units and the area of overlapping of the edge sieve on the direction of air flows in the grinding chamber and to determine the working area of the edge sieve. Angle hammers are characterized by the movement of air flows in the axial direction and their following distribution: suction into the grinding chamber in the central part of the end sieve and ejection along the outer circumference of the sieve. Based on this, the entire area of the end sieve can be divided into three parts: the suction zone, the ejection zone and the transition zone. An increase in the length of the angular blades leads to an increase in the working area of the end screens, therefore, the use of combined working units is rational. Installation of working units in the form of straight hammers is impractical, since the working area of the end screens is minimal. It is also irrational to use working units in the form of angle hammers, since they are characterized by the maximum area of the retraction zone and a small working area of the end sieves

P732Maternal high-fat diet promotes the expansion of abdominal aortic aneurysm in adult offspring by enhancing osteoclast-like macrophage differentiation

Background and objective Maternal high-fat diet (HFD) has been shown to modulate vascular function and remodeling in adult offspring. Here, we investigated the impact of maternal HFD on abdominal aortic aneurysm (AAA) formation. Methods and results Eight-week-old female wild-type mice (C57BL/6) were fed a HFD or normal diet (ND) one week prior to mating and received during pregnancy and lactation. In eight-week-old offspring of both genders, AAA was induced with the application of 0.5M calcium chloride (CaCl2) on the infrarenal aorta. Male offspring of HFD-fed dams (O-HFD) showed a significant increase in maximum outer diameter of AAA at 1, 4 and 8 weeks after surgery compared with offspring of ND-fed dams (O-ND) (P<0.05). The lengths of outer circumference assessed by histological analysis were increased in O-HFD (P<0.05). Likewise, female O-HFD showed a greater length of outer circumference than female O-ND (P<0.05). While the number of F4/80-positive cells at 1 wk after surgery was comparable between the male O-HFD and O-ND, the percentage of MMP-9/F4/80 double-positive cells was significantly increased in male O-HFD. Consistently, fluorescent image of abdominal aorta taken by IVIS at 1 wk after surgery revealed a 2-fold increase in MMP activity (P<0.01). Intriguingly, F4/80-positive cells in male O-HFD showed a 2.5-fold increase in co-staining with tartrate-resistant acid phosphate (TRAP), typical marker of osteoclast-like macrophages which abundantly secrete proteases than classically activated macrophages (M1), while the percentage of TNF-α/F4/80 double-positive cells was comparable between the 2 groups. Pharmacological inhibition of osteoclastogenesis by zoledronic acid (ZA) (100μg/kg) completely abolished the exaggerated AAA development in male O-HFD to a similar extent of that in male O-ND, while AAA development in male O-ND mice did not change even after ZA treatment. Furthermore, in vitro TNF-α-induced osteoclast differentiation of bone marrow-derived macrophages (BMDMs) showed a significantly higher number of TRAP-positive cells, accompanied by increased calcitonin receptor mRNA expression. Western blotting analysis showed that protein expression level of NFATc1, master regulator of osteoclastogenesis, was significantly higher in BMDM of O-HFD than O-ND. Conclusion Our findings demonstrate that maternal HFD accelerates CaCl2-induced AAA expansion, accompanied by the exaggerated accumulation of osteoclast-like macrophages and augmented activity of MMPs. Inhibition of macrophages skewing toward osteoclast-like cells could be a potential therapeutic target for preventing AAA development.

Variable Inertia Damper Using a Flywheel Filled by MR Fluid

To get a variable inertia effect for vibration reduction, a semiactive damper using a flywheel filled by MR fluid was developed. The damper comprises a ball screw mechanism and the flywheel, which is able to change a moment of inertia. MR fluid is filled into the flywheel. Particles are clustered at outer circumference edge inside the wheel when the magnetic field is applied to the wheel edge, so the moment of inertia on the flywheel can be changed artificially. The prototype device was manufactured, and the dynamic performance was investigated. Finally the changeable inertia effect was confirmed experimentally.

Abdominal Obesity Index as an Alternative Central Obesity Measurement During a Physical Examination

Background: Although BMI (body mass index) has been widely used to determine whether an individual is underweight, normal weight, overweight, or obese, its clinical usefulness for obesity study has been called into question because it does not specifically describe body fat content and distribution and has limited relevance to central obesity, which is most relevant to health risks. Although imaging techniques are used to determine central obesity, they are expensive and are thus not used in a routine physical examination of patients in medical offices. Objective: Developing an easy-to-use ABOI (Abdominal Obesity index) to measure central obesity during a physical examination. Methods: ABOI is an index utilized to assess central obesity of patients. To determine ABOI, two measurements are taken from the torso; the outer circumference of the thoracic segment, C1, at the xiphoid process and the outer circumference of the abdominal segment, C2, at the point of largest girth. The volume of the abdominal segment is divided by the volume of the thoracic segment to derive ABOI (V2/V1 = [C2]2/[C1]2). Thus, ABOI is the square of the ratio of the circumference of the abdominal segment to the circumference of the thoracic segment of the torso. Moreover, the ABOI does not concern total body weight, body height, or body shape (e.g. “apple-shaped” or “pear-shaped” body types). Instead, ABOI specifically highlights central obesity. We randomly recruited 282 subjects, ages 20-90 years, at a community health service center in Beijing, China, and determined their ABOI and BMI values. Results: The mean (standard deviation) BMI for the female and male subjects is, respectively, 24.24 kg/m2 (3.35) and 24.86 kg/m2 (3.25). For ABOI, mean (standard deviation) is 1.17 (0.16) and 1.01 (0.13) for females and males, respectively. There is no strict relationship between ABOI and BMI in the context of obesity as defined by high BMI values, and ABOI appears to be a more specific measure of central obesity than BMI. Conclusion: ABOI is a useful and distinct independent measurement of central obesity, and ABOI (possibly in combination with the waist-to-height ratio) appears to be a more specific way to assess central obesity during a physical examination.