36 research outputs found
Quality Measurement of Two Phase Flow with Plug Flow
In order to control refrigeration cycles employing an injection system properly, it is important to detect quality of gas–liquid two-phase refrigerant in a two-phase region of the cycle. Although there are some techniques such as using a capacitance sensor or a X-ray beam scanning to measure a cross-sectional void fraction of the gas-liquid two-phase flow in a pipe, the measurement of the quality or flow rate of each phase is quite difficult since the liquid phase and gas phase of two-phase flow flowing in a pipe have different velocities in most cases. Meanwhile, the flow through a narrow tube becomes plug flow and the velocities of gas plug and liquid plug are almost the same. Therefore, the void fraction or quality of two-phase flow with plug flow in the narrow tube can be measured by detecting each plug length. Authors have examined the quality measurement of two-phase flow in the refrigeration cycle based on the plug flow characteristics. In previous studies, it was confirmed that the quality can be measured with an accuracy of about ±10% when the flow regime is plug flow in the narrow tube. However, the quality range where the flow regime becomes the plug flow is limited to the quality less than 0.1. In this study, multiple narrow tubes are installed with a gas bypass line to extend the quality range to be measured. Consequently, the measurable range of quality up to 0.8 was achieved with an accuracy of ±10%
Cholecystomucoclasis: Revaluation of safety and validity in aged populations
Background: We evaluated the safety and validity of cholecystomucoclasis (CM) and compared its intraoperative characteristics with those of standard cholecystectomy (SC).Methods: We enrolled 174 patients who underwent cholecystectomy and retrospectively evaluated the outcomes of patients in the SC and CM groups.Results: Significant differences in age (71.1 vs. 61.9 years), American Society of Anesthesiologists physical status (ASA-PS), and serum C-reactive protein levels (CRP) (18.1 vs. 4.7 mg/dL) were observed between the CM and SC groups. Conversely, no significant differences were observed in the operation time (129 vs. 108 min), amount of blood loss (147 vs. 80 mL), intraoperative complications (0% vs. 5.7%), or duration of hospital stay (13.2 vs. 8.9 days) between the 2 groups. A high conversion rate (35.3%), postoperative complications (33%), and frequent drain insertions (94%) were observed in the CM group.Conclusions: CM is a safe and valid surgical procedure and surgeons should not hesitate to transition to CM for patients who are of advanced age, in poor general condition (high ASA classification), or have high levels of serum CRP. © 2012 Tsukada et al.; licensee BioMed Central Ltd
Expression of human thromboxane synthase using a baculovirus system
AbstractHuman thromboxane (TX) synthase (EC 5.3.99.5) was produced by the baculovirus expression system using cDNA encoding human TX synthase [(1991) Biochem. Biophys. Res. Commun. 78, 1479-1484]. A recombinant baculovirus TXS7 was expressed in Spodoptera frugiperda Sf9 insect cells. The expressed protein was recognized by monoclonal antibody, Kon 7 raised against human TX synthase [(1990) Blood 76, 80-85]. The recombinant TX synthase catalyzed the conversion of prostaglandin (PG) H2 to TXA2 and 12-hydroxy-heptadecatrienoic acid (HHT). Both conversions of PGH2 to TXA2 and HHT by the expressed TX synthase were completely inhibited by a specific TX synthase inhibitor, OKY-046 (5 μM)
Expression of human thromboxane synthase using a baculovirus system
AbstractHuman thromboxane (TX) synthase (EC 5.3.99.5) was produced by the baculovirus expression system using cDNA encoding human TX synthase [(1991) Biochem. Biophys. Res. Commun. 78, 1479-1484]. A recombinant baculovirus TXS7 was expressed in Spodoptera frugiperda Sf9 insect cells. The expressed protein was recognized by monoclonal antibody, Kon 7 raised against human TX synthase [(1990) Blood 76, 80-85]. The recombinant TX synthase catalyzed the conversion of prostaglandin (PG) H2 to TXA2 and 12-hydroxy-heptadecatrienoic acid (HHT). Both conversions of PGH2 to TXA2 and HHT by the expressed TX synthase were completely inhibited by a specific TX synthase inhibitor, OKY-046 (5 μM)
Estrogenic Activities of Fatty Acids and a Sterol Isolated from Royal Jelly
We have previously reported that royal jelly (RJ) from honeybees (Apis mellifera) has weak estrogenic activity mediated by interaction with estrogen receptors that leads to changes in gene expression and cell proliferation. In this study, we isolated four compounds from RJ that exhibit estrogenic activity as evaluated by a ligand-binding assay for the estrogen receptor (ER) β. These compounds were identified as 10-hydroxy-trans-2-decenoic acid, 10-hydroxydecanoic acid, trans-2-decenoic acid and 24-methylenecholesterol. All these compounds inhibited binding of 17β-estradiol to ERβ, although more weakly than diethylstilbestrol or phytoestrogens. However, these compounds had little or no effect on the binding of 17β-estradiol to ERα. Expression assays suggested that these compounds activated ER, as evidenced by enhanced transcription of a reporter gene containing an estrogen-responsive element. Treatment of MCF-7 cells with these compounds enhanced their proliferation, but concomitant treatment with tamoxifen blocked this effect. Exposure of immature rats to these compounds by subcutaneous injection induced mild hypertrophy of the luminal epithelium of the uterus, but was not associated with an increase in uterine weight. These findings provide evidence that these compounds contribute to the estrogenic effect of RJ