Serum type IV collagen-degrading enzyme in hepatocellular carcinoma with metastasis.

The activity of serum type IV collagen-degrading enzyme was measured in 18 patients with hepatocellular carcinoma (HCC). The enzyme activity was significantly higher, in HCC patients with a tumor thrombus in the portal vein than in healthy controls, liver cirrhosis patients and HCC patients without a tumor thrombus. Moreover, the activity in HCC patients with lung metastasis tended to be higher than that in HCC patients without lung metastasis. The activity of serum type IV collagen-degrading enzyme did not correlate with tumor size, serum alpha-fetoprotein level, or macroscopic classification of tumor growth. These results suggest that the activity of serum type IV collagen-degrading enzyme represents the metastatic potential or the ongoing metastatic activity of HCC. The enzyme is a useful serum marker of metastasis from HCC.</p

Empirical Calculation Method of Bypass Leakage in Scroll Compressors

This study presents an empirical method to calculate the bypass leakage mass flow rate along the tip seal in a scroll compressor. The leakage flows through small axial and radial clearances between the orbiting and fixed scrolls of scroll compressor were previously studied by Ishii et al. In these earlier studies, the pressure decay in the pressurized vessel due to leakage through the axial and radial clearances was measured using a maximum pressure of 3 MPa for CO2 and 0.6 MPa for R22. The Darcy-Weisbach equation for incompressible, viscous fluid flow through the thin rectangular cross-section was applied to calculate the leakage mass flow rate that matched the pressure decay characteristics. The empirical friction factors were determined and plotted on a Moody diagram. As a result, the empirical friction factors for both axial and radial clearance leakage flows have been determined and shown to take on essentially the same value for both CO2 and R22, despite the significantly different working pressures. In contrast, the flow patterns in bypass leakage along the tip seal are so complicated that not even the leakage characteristics are known definitively. No method exists for calculating the bypass leakage mass flow rate. In the present study, a bypass leakage model was constructed, compatible with a production-type scroll compressor with a large cooling capacity. A similar test of the pressure decay in the pressurized vessel due to bypass leakages were conducted with the refrigerant gas R410A. The measured pressure decay characteristics were then simulated by the Darcy-Weisbach equation with the empirical friction factors from our previous study for the leakage flow through the axial clearance. In the present simulations of the measured pressure decay, the complicated flow patterns through bypass clearances were classified into two representative rectangular thin cross-section leakage passes, one with an equivalent width and the other with an equivalent length. Empirical friction factor values for the equivalent pass width and length were determined to match the measured pressure decays. As a result, the calculation of the bypass leakage flow rate along the tip seal in scroll compressors can be accomplished using a simple scheme in terms of the equivalent pass width and equivalent pass length for two representative leakage passes forming a thin rectangular cross-section and applying empirically determined friction factors,

Type IV collagen-degrading enzyme activity in human serum.

Type IV collagen-degrading enzyme activity was detected in human serum. Serum was preincubated with 4-aminophenylmercuric acetate and trypsin to activate the enzyme prior to assay. Type IV collagen, purified from human placentas and radiolabeled with [1-14C] acetic anhydride, was used as the substrate. The enzyme activity was measured at pH 7.5 and inhibited by treatment with ethylenediaminetetraacetic acid or heat. The assay of type IV collagen-degrading enzyme in human serum might be useful for estimating the degradation of type IV collagen.</p

Hydrodynamic-Pressure-Induced Elastic Deformation of Thrust Slide-Bearings in Scroll Compressors and Oil Film Pressure Increase Due to Oil Envelopment

This paper presents the concept of the Elasto-Hydrodynamic Lubrication?EHL?of thrust slide-bearings in scroll compressors, resulting in the superior lubrication characteristics of these bearings. The thrust plate undergoes elastic deformation due to axial loading, resulting in the formation of a uniform fluid wedge between the orbiting and fixed thrust plates. This wedge region has very high induced oil film pressure, which explains the remarkably good lubrication characteristics of the thrust slide-bearing. Furthermore, the high oil film pressure induces further local elastic deformation of the thrust plate, forming an EHL oil pocket with the thrust plate and a further increase in the oil film pressure between the sliding surfaces due to this oil envelopment. The formation of the EHL pocket was confirmed using FEM analysis and lubrication tests on the elastic deformation of the thrust plate. Subsequently, the additional increase in oil film pressure, due to the EHL pocket effect, was examined in computer simulations applying the average Reynolds equation for the boundary of elastic deformation of the thrust plate. In these studies, a 6.7% increase in oil film pressure was ascertained for a small cooling capacity scroll compressor driven at 3600 rpm with 0.1 kW motor. The oil envelopment contributes to the superior lubrication performance of the thrust slide bearings scroll compressors

Optimization of EHL Lubrication Performance in Thrust Slide-Bearings of Scroll Compressors

Previous studies [Refs. 1, 2] revealed the formation of a uniform oil wedge at the periphery of the thrust plate, caused by the elastic deformation of the orbiting thrust plate due to the pressure difference across the orbiting thrust plate, is a significant factor in the high lubrication performance in thrust slide-bearings. In addition to the uniform wedge formation, the high oil film pressure also induces a local elastic deformation of the fixed thrust plate normal to its surface. The normal thrust plate deformation and the oil wedge effectively form an elasto-hydrodynamic-lubrication (EHL) pocket, even more effectively increasing the oil film pressure between the sliding surfaces, due to the envelopment of the oil, as confirmed in our companion paper [3], and an earlier, less-detailed contribution [4]. The present study focuses on aspects of EHL that have both positive and negative effects on the lubrication performance of the thrust slide-bearings in scroll compressors. Theoretical calculations using the average Reynolds equation and Patier-Chen solid contact theory, for the boundary of the local elastic deformation of the thrust slide-bearing, were conducted for a small cooling capacity scroll compressor driven at 3600 rpm with 0.1 kW. An approximate method was developed using characteristic curves to determine the oil film axial force, the average oil film thickness, the frictional force and the frictional coefficient. The calculations considered a variety of pressure differences due to the operation pressure and the thickness of thrust plate. Also cases with a fixed uniform wedge angle at the periphery were calculated. The calculated results suggest a possible maximum reduction in frictional coefficient of about 55% compared to that with a fixed uniform wedge angle. The reduction rate increases with decreasing thrust plate thickness, which, however, restricts the operation pressures to a lower pressure range. Design guidelines for optimizing EHL will be suggested. References: [1] Oku, T., Ishii, N., Anami, K., Knisely, C.W., Sawai, K., Morimoto, T., Hiwata, A. : Theoretical Model of Lubrication Mechanism in the Thrust Slide-Bearing of Scroll Compressors, HVAC&R Research Journal ASHRAE Vol.14, No.2, pp.239-358, 2008-3. [2] Ishii, N., Oku, T., Anami, K., Knisely, C.W., Sawai, K., Morimoto, T., Iida, N. : Experimental Study of the Lubrication Mechanism for Thrust Slide Bearings in Scroll Compressors, HVAC&R Research Journal ASHRAE Vol.14, No.2, 2008-4. [3] Ishii, N., Tsuji, T., Anami, K., Nokiyama, K., Morimoto, T., Sakuda, A., Oku, T., Sawai, K., Knisely, C.W., : “Hydrodynamic-Pressure-Induced Elastic Deformation of Thrust Slide-Bearings in Scroll Compressors and Oil Film Pressure Increase Due to Oil Envelopment,” abstract submitted to 2014 Purdue Herrick Conferences. [4] Ishii, N., Tsuji, T., Oku, T., Anami, K., Knisely, C.W., Nokiyama, K., Morimoto, T., Sakuda, A., Sawai, K. 2012 “Elasto-Hydrodynamic Lubrication Effect in Thrust-Slide Bearings of Scroll Compressors,” 2012 Purdue Conference Paper on (Paper 1438)

Proposal and Evaluation of Toilet Timing Suggestion Methods for the Elderly

Elderly people need to urinate frequently, and when they go on outings they often have a difficult time finding restrooms. Because of this, researching a body water management system is needed. Our proposed system calculates timing trips to the toilet in consideration with both their schedules and the amount of body water needing to be expelled, and recommends using the restroom with sufficient time before needing to urinate. In this paper, we describe the suggested methods of this system and show the experimental results for the toilet timing suggestion methods

Evaluation of chemical-specific IgG antibodies in male workers from a urethane foam factory

Background: Plastic resins are complex chemicals that contain toluene diisocyanate (TDI) and/or trimellitic anhydride (TMA), which cause occupational allergies (OA), including respiratory allergies. Serum IgGs against TDI and TMA have been suggested as potential markers of the exposure status and as exploring cause of OA. Although TDI-specific IgG has been examined for suspected OA, TMA-specific IgG is not commonly evaluated in a urethane foam factory. This study therefore investigated both TDI- and TMA-specific IgGs in suspected OA patients and to evaluate the usefulness of the measurement of multiple chemical-specific IgG measurement for practical monitoring. Methods: Blood samples were collected from two male workers who developed respiratory allergies supposedly caused by occupational exposure to TDI and/or TMA for the presence of TDI- and TMA-specific IgGs. In addition, blood samples from 75 male workers from a urethane foam factory, along with 87 male control subjects, were collected in 2014 and tested for the same IgGs in 2014. The presence and levels of TDI- and TMA-specific serum IgGs were measured using dot blot assays. Results: We found that controls had mean concentrations of TDI- and TMA-specific IgGs of 0.98 and 2.10 μg/mL, respectively. In the two workers with respiratory allergies, the TDI-specific IgG concentrations were 15.6 and 9.51 μg/ mL, and TMA-specific IgG concentrations were 4.56 and 14.4 μg/mL, which are clearly higher than those in controls. Mean concentrations of TDI- and TMA-specific IgGs in the factory workers were 1.89 and 2.41 μg/mL, respectively, and are significantly higher than those of the controls (P < 0.001 and P < 0.026 for TDI- and TMA-specific IgGs, respectively). Conclusion: The workers suspected of OA showed an evidently high level of TDI- and TMA-specific IgG, and these levels in workers at the urethane foam factory were also significantly higher than those in controls. In conclusion, the measurement of TDI- and TMA-specific IgG among workers using plastic resins is helpful to monitor their exposure status.This study was funded by an Industrial Disease Clinical Research Grant (grant number 14040101-02 to M.T.) and the JSPS KAKENHI (grant numbers 22790546 and 25860472 to M.T.)

Surgical treatment for Crohn's disease.

The medical records of 16 consecutive patients with Crohn's disease surgically treated in our department from 1978 to 1993 were retrospectively reviewed. The indication for surgery was obstructive symptoms due to Crohn's strictures that were unresponsive to conservative therapy. The types of operations performed were classified into five categories. Nine patients (56.3%) had small bowel resection only, 4 (25.0%) underwent an ileocolonic resection, 1 (6.3%) had a total colectomy, 1 (6.3%) had Mile's operation and 1 (6.3%) had subtotal gastrectomy with gastrojejunostomy and antral mucosectomy. Of these 16 patients, 13 (81.3%) had resection with a single anastomosis and strictureplasty was concomitantly performed in only 2 cases (12.5%). Crohn's disease recurred in 3 patients (18.8%), 1 of whom required a second operation.</p