Stiffness Measurement System Using Endoscopes with a Visualization Method

A novel stiffness-sensing system was developed that works by attaching the proposed sensing part to endoscopes or cameras. The system provides a method to investigate the stiffness of tissues or objects in deep areas that can only be observed with endoscopes in order to detect abnormalities. The system is an extension of our previous force sensing system that utilized a force visualization mechanism. The force is visualized at the sensing part, and can be measured as visual information via endoscopes or cameras. The sensing part also has a limiting structure used as a threshold for the applied force. By measuring the force at the limitation, the stiffness can be measured. The limitation point is detected by the brightness changes of the captured images. The developed sensing part has the advantages of having no electronic components, being disposable, simple, easy to sterilize, MRI-compatible, and low-cost. Image processing methods for realizing the mechanism are also proposed. The system was experimentally validated. © 2001-2012 IEEE

Visualization Method Based Stiffness Sensing System for Endoscopes

This research developed novel stiffness sensing system attachable to endoscope. The system is an extension of our previous force sensing systems utilizing force visualization mechanism. The sensing part is attached to endoscopes. The force is visualized at the sensing part, and can be measured as visual information via endoscopes. The sensing part also has a structure of limiting the pressing amount. By measuring force at the limitation, the stiffness can be measured. The developed sensing part has the features of no electrical components, disposable, simple, easy sterilization, MRI-compatibility, and low-cost. The validation of the system was experimentally shown. © 2015 IEEE.37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBC 2015; MiCo Center, Milano Congressi CenterMilan; Italy; 25 August 2015 through 29 August 2015; Category numberCFP15EMB-ART; Code 11680

UV-Induced Ubiquitylation of XPC Protein Mediated by UV-DDB-Ubiquitin Ligase Complex

SummaryThe xeroderma pigmentosum group C (XPC) protein complex plays a key role in recognizing DNA damage throughout the genome for mammalian nucleotide excision repair (NER). Ultraviolet light (UV)-damaged DNA binding protein (UV-DDB) is another complex that appears to be involved in the recognition of NER-inducing damage, although the precise role it plays and its relationship to XPC remain to be elucidated. Here we show that XPC undergoes reversible ubiquitylation upon UV irradiation of cells and that this depends on the presence of functional UV-DDB activity. XPC and UV-DDB were demonstrated to interact physically, and both are polyubiquitylated by the recombinant UV-DDB-ubiquitin ligase complex. The polyubiquitylation altered the DNA binding properties of XPC and UV-DDB and appeared to be required for cell-free NER of UV-induced (6-4) photoproducts specifically when UV-DDB was bound to the lesion. Our results strongly suggest that ubiquitylation plays a critical role in the transfer of the UV-induced lesion from UV-DDB to XPC

Silicone retractor with embedded force-sensing function for attachment to surgical suction pipes

A silicone retractor that can be attached to suction pipes was developed in order to enhance the usability [1]. The measurement of the retracting force is desired in order to avoid damage to brain tissue due to an unexpected large force. This paper presents a force-sensing embedded silicone retractor that can be attached to suction pipes. The developed silicone retractor can provide three functions at the same time: suction, retracting, and retracting force measurement. The force-sensing system is based on a visualization mechanism that displays the force as a colored pole motion. The surgeon can then roughly estimate the retracting force. With a fiberscope, the retracting force can be measured with a resolution of 0.05-0.3 N. The retractor is made of silicone and has the advantages of disposability, low cost, and easy sterilization/disinfection. The system was validated through finite element method analysis and experiments. © 2015 IEEE.IEEE/ASME International Conference on Advanced Intelligent Mechatronics, AIM 2015; BEXCOBusan; South Korea; 7 July 2015 through 11 July 2015; Category numberCFP15775-ART; Code 11713

Functional regulation of the DNA damage-recognition factor DDB2 by ubiquitination and interaction with xeroderma pigmentosum group C protein

In mammalian nucleotide excision repair, the DDB1-DDB2 complex recognizes UV-induced DNA photolesions and facilitates recruitment of the XPC complex. Upon binding to damaged DNA, the Cullin 4 ubiquitin ligase associated with DDB1-DDB2 is activated and ubiquitinates DDB2 and XPC. The structurally disordered N-terminal tail of DDB2 contains seven lysines identified as major sites for ubiquitination that target the protein for proteasomal degradation; however, the precise biological functions of these modifications remained unknown. By exogenous expression of mutant DDB2 proteins in normal human fibroblasts, here we show that the N-terminal tail of DDB2 is involved in regulation of cellular responses to UV. By striking contrast with behaviors of exogenous DDB2, the endogenous DDB2 protein was stabilized even after UV irradiation as a function of the XPC expression level. Furthermore, XPC competitively suppressed ubiquitination of DDB2 in vitro, and this effect was significantly promoted by centrin-2, which augments the DNA damage-recognition activity of XPC. Based on these findings, we propose that in cells exposed to UV, DDB2 is protected by XPC from ubiquitination and degradation in a stochastic manner; thus XPC allows DDB2 to initiate multiple rounds of repair events, thereby contributing to the persistence of cellular DNA repair capacit

A Study on the Physical Sensations of Four Kinds of Trial Toothbrushes and Four Different Toothbrushing Methods

Using 65 students of the hygiene school attached to Matsumoto Dental College (35 first-year students, 30 second-year students) as subjects, we performed an investigation into the different physical sensations produced when using 4 trial toothbrushes and 4 different toothbrushing methods. The conclusions are as follows: 1. "Length of brush": There was a tendency to reply that the length of brush seemed slightly shorter when the students brushed with the Roll method, rather than the other three methods. 2. "Stiffness of filaments": There was a tendency to reply that the bristle was much harder when the students brushed with methods from Group B (Methods that primarily use the tip of the bristle) than with methods from Group A (Methods which use the side of the bristle). 3. "Tooth brush wear": A large percentage of students replied that the bristle was more durable when using methods from Group B rather than Group A. 4. "Physical sensation on tooth and gingiva": Brush M and the Open-tufted brush, both classified as "medium" stiffness, were preferred. 5. "Physical sensation of holding the handle": 80-90% of the students, regardless of the toothbrushing method employed, liked the handles of the brushes

Role of Gremlins in the Aortic Arch of Spontaneously Hypertensive and Hyperlipidemic Rats

Atherosclerosis is a lifestyle-related disease that plays a major role in cardiovascular disease. Recently, we found that gene expression of Gremlin 2, an antagonist of bone morphogenetic protein (BMP), was significantly increased in the aorta of spontaneously hypertensive and hyperlipidemic rats (SHHRs) fed a high-fat, 30% sucrose solution diet (HFDS). However, the role of Gremlin 1 (Grem1) and Gremlin 2 (Grem2) in the aortic arch of rats under hypertensive, hyperlipidemic, and hyperglycemic conditions remains unclear. Therefore, in the present study we investigated the molecular role of Gremlins in the aorta of SHHRs. Four-month-old male Sprague-Dawley rats and SHHRs were fed a normal diet or the HFDS ad libitum for 4 months. Then, gene and protein expression was analyzed using quantitative polymerase chain reaction and western blotting, respectively. Grem1 and Grem2 protein expression was increased, whereas phosphorylated Smad1/5 protein expression was low, in the aorta of SHHRs fed the HFDS. In addition, the expression of the downstream gene targets of BMP, namely inhibitor of DNA binding 1 (Id1) and atonal homolog 8 (Atoh8), was decreased in aortas of SHHRs fed the HFDS. Furthermore, mRNA expression of Snail, α-smooth muscle actin (αSMA), and Fibronectin was increased in SHHRs fed the HFDS. These findings suggest that upregulation of Gremlins attenuates the activation of BMP signaling, which contributes to fibrogenesis of the aorta

Vildagliptin Improves Glucose Tolerance and Decreases Plasma Triglycerides in Sprague-Dawley Rats

The number of patients with lifestyle-related diseases, including type 2 diabetes, is increasing. The onset of type 2 diabetes can be prevented by dietary and exercise interventions, as well as drug therapy. Dipeptidyl peptidase-4 inhibitors and glucagon-like peptide-1 receptor agonists have attracted attention recently as treatments for diabetes, and incretin hormones have been reported to have a protective effect on pancreatic β-cells. It is not clear whether vildagliptin (VIL) can prevent the progression of lifestyle-related disease. Thus, in the present study, Sprague-Dawley rats were fed a high-fat diet with sucrose water (HFDS) to determine whether VIL could inhibit deterioration in glucose tolerance and improve other biomarkers of lipid disorder. Four-month-old male Sprague-Dawley rats were divided into three groups (n = 7 in each group); one group was fed a normal diet for 4 months, whereas the remaining two groups were fed the HFDS, with or without VIL for 4 months. When rats were 7 months of age, they were subjected to an intraperitoneal glucose tolerance test (IPGTT); biomarkers of lipid disorder were measured in 8-month-old rats. There was a decrease in the glucose spike in the IPGTT 10min after loading in the HFDS + VIL group and plasma triglyceride (TG) levels were significantly lower in these rats compared with the HFDS group. The decreased TG levels in HFDS + VIL rats were accompanied by decreases in plasma chylomicron levels. These results suggest that VIL can prophylactically inhibit decreases in pancreatic β-cell function in type 2 diabetes and reduce the risk of cardiovascular disease due to high TG levels. Thus, VIL administration may contribute to the prevention of lifestyle-related disease