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Agglomeration, coalescence and flotation of non-metallic inclusions in steel melt are effective for obtaining “clean steel.” In this study, the agglomeration and breakup behaviors of particles with a primary particle size distribution (hereinafter, polydisperse particles) in a liquid under impeller and gas stirring were compared by numerical calculations and model experiments. The particle-size-grouping (PSG) method in the numerical agglomeration model of particles was combined with a breakup term of agglomeration due to bubble bursting at the free surface. Polydisperse and monodisperse polymethylmethacrylate (PMMA) particles were used in the agglomeration experiments. The agglomeration rate of the polydisperse particles under impeller stirring was increased by an increasing energy input rate, whereas the agglomeration rate under gas stirring decreased under this condition due to the larger contribution of the breakup of agglomerated particles during bubble bursting in gas stirring. At the same energy input rate, agglomeration of polydisperse particles was larger under impeller stirring than under gas stirring. The agglomeration rate of polydisperse particles was larger than that of monodisperse particles under both impeller and gas stirring at the same energy input rate. The computational temporal changes in the total number of particles were in good agreement with the experimental results. This means that the difference in the agglomeration behaviors observed in impeller and gas stirring can be explained by the turbulent coagulation and subsequent agglomerated particle breakup in gas stirring. The computational temporal change in the number of each group approximately agreed with the experimental change in both impeller and gas stirring.

Mechanical testing and gait measurement for ankle-foot orthosis (AFO) are crucial for determining the AFO stiffness magnitude in an individual. However, information on the effect of the stiffness magnitude on the muscle force during gait is limited. This study aimed to investigate the relationship between the AFO stiffness and ankle muscle force during gait. The AFO stiffness was mechanically tested using a six-axis robot arm. The stiffness magnitude was adjusted using different spring constants. Five stiffness conditions were set for each plantarflexion resistive (PFR) and dorsiflexion resistive (DFR) function. The effect of the PFR and DFR on the ankle muscle force during gait were determined using musculoskeletal and AFO models. Tibialis anterior (TA) and triceps surae (TS) muscle forces were calculated through gait simulation. The angle-moment relationships display hysteresis loops for each condition. One of the PFR and DFR conditions differed significantly from the others (for all, p < 0.05). In order of lower stiffness, the each PFR contribution ratio to the peak TA muscle force normalized in the no-stiffness condition was 8.4%, 10.8%, 11.3%, 13.5%, and 15.3%; while the each DFR contribution ratio to the peak TS muscle force was 16.2%, 20.9%, 25.3%, 29.8%, and 30.5%, respectively. Through mechanical testing as well as gait simulation, it was demonstrated that the magnitude of the AFO stiffness decreased the required ankle muscle force during gait. This study can contribute to more effective gait rehabilitation using AFO as well as AFO fabrication with customized stiffness for individual gait function.

Recent studies have shown that air pollution is intense and hazardous in Asia compared to other parts of the world due to the late and poor implementation of updated technology in automobiles and industry as well as to the high population density. Respiratory disease, including asthma, is exacerbated by air pollution. However, the effects of PM_(2.5), especially on respiratory allergies in Asian cities, have not yet been examined in detail. In this study, airway epithelial cells were exposed to crude PM_(2.5) particles collected by cyclonic separation from three different Asian cities, namely, Sakai, Bangkok, and Taipei. We compared the cytotoxicity and inflammatory potential of the PM_(2.5) from these cities by measuring IL-6 and IL-8. The samples from Sakai and Bangkok caused cytotoxic effects at a dose of 75 μg mL^(-1) and, moreover, induced the release of IL-6 and IL-8 even at low doses. The release of these two interleukins was highly associated with fluoranthene derivatives, microbial factors (endotoxin and β-glucan), metals (e.g., Ti), and organic (OC2 and OC3) and elemental carbon (EC1) in the PM_(2.5). Thus, these components potentially contribute to cellular damage and a pro-inflammatory response in the airway epithelial cells, and the effect depends on PM_(2.5) sources in the locations.

Measures for protecting against PM2.5 (particulate matter with aerodynamic diameters ≤2.5 µm), which exacerbates respiratory diseases, have not been established. The present study investigated the effects of extracts of curry powder and its components on pro-inflammatory responses, extracellular and intracellular reactive oxygen species (ROS) production, induced by the PM2.5 component, DEP (diesel exhaust particles). Airway epithelial cells were exposed to DEP in the presence of curry powder, or its major and/or anti-inflammatory components, clove and turmeric. Curry powder, clove, and turmeric inhibited DEP-induced IL-6 release and extracellular ROS; in the absence of clove and turmeric, these effects of curry powder were mild but similar. Among the other curry spices, cinnamon decreased IL-6 and extracellular ROS, and coriander decreased IL-6 alone. This is the first report on the protective effects of extracts of curry powder and its components, against PM2.5-induced airway inflammation, which may be partly through inhibition of extracellular ROS.

Ambient particulate matter (PM) epidemiologically exacerbates respiratory and immune health, including allergic rhinitis (AR) and bronchial asthma (BA). Although fine and coarse particles can affect respiratory tract, the differences in their effects on the upper and lower respiratory tract and immune system, their underlying mechanism, and the components responsible for the adverse health effects have not been yet completely elucidated. In this study, ambient fine and coarse particles were collected at three different locations in Japan by cyclone technique. Both particles collected at all locations decreased the viability of nasal epithelial cells and antigen presenting cells (APCs), increased the production of IL-6, IL-8, and IL-1β from bronchial epithelial cells and APCs, and induced expression of dendritic and epithelial cell (DEC) 205 on APCs. Differences in inflammatory responses, but not in cytotoxicity, were shown between both particles, and among three locations. Some components such as Ti, Co, Zn, Pb, As, OC (organic carbon) and EC (elemental carbon) showed significant correlations to inflammatory responses or cytotoxicity. These results suggest that ambient fine and coarse particles differently affect nasal and bronchial epithelial cells and immune response, which may depend on particles size diameter, chemical composition and source related particles types.

Particulate matter with diameters

We investigated the synergic effects of components of particulate matter with aerodynamic diameters ≤2.5 μm (PM2.5) on airway inflammation. Co-exposure to cadmium (Cd) and 9,10-phenanthrenequinone (9,10-PQ) additively/synergistically increased pro-inflammatory responses in airway epithelial cells, whereas co-exposure to Cd and phenanthrene resulted in no acceleration. These results suggest that the combination of metal and a quinone derivative can contribute to the exacerbation of respiratory diseases by PM2.5.

Particulate matter with diameters2.5 μm (i.e., PM

Background and Aim: During catheter exchange for percutaneous endoscopic gastrostomy (PEG), endoscopic or radiological observation is widely used to confirm that the catheter is placed correctly. However, to carry out these procedures in all patients at every catheter exchange costs time and money. It is therefore important to develop a reliable and safe method, which can also be used outside the clinic, to check the exchanged catheter. We examined the usefulness and safety of intragastric observation using a small-diameter rigid telescope, which can be inserted through the catheter lumen of a PEG tube. Methods: Before and after catheter exchange, observation was carried out using the rigid telescope E02700 (external diameter: 2.7 mm; Nisco Co., Tokyo, Japan). After air insufflation by the novel air-supplying adaptor, the rigid telescope was inserted through the button catheter for observation of the fistula and gastric lumen with guidewire introduction. Next, the old gastrostomy catheter was replaced by a new one, using the guidewire technique. Subsequently, the telescope was re-inserted to check the fistula and gastric lumen. Results: With this technique, observation inside the stomach as well as inside the fistula was achieved without any complication during all 80 exchange trials in the 55 patients studied. A homemade adaptor was used effectively to convey air and water into the stomach during the observation. Conclusion: It is suggested that observation inside the stomach using a small-diameter rigid telescope at the time of gastrostomy exchange is useful and safe for checking the location of the newly fixed catheter.

A 68-year-old man with hemophilia A and liver cirrhosis caused by hepatitis C virus was referred to our hospital to receive prophylactic endoscopic treatment for gastroesophageal varices (GOV). He had large, tense, and winding esophageal varices (EV) with cherry red spots extending down to lesser curve, predicting the likelihood of bleeding. Esophageal endoscopic injection sclerotherapy (EIS) was performed with a total 15 mL of 5% ethanolamine oleate with iopamidol (EOI). Radiographic imaging during EIS demonstrated that 5% EOI reached the afferent vein of the varices. He was administered sufficient factor VIII concentrate before and after EIS to prevent massive bleeding from the varices. Seven days after EIS, upper gastrointestinal endoscopy (UGIE) showed that the varices were eradicated almost completely. Eighteen months after EIS, the varices continued to diminish. We report a successful case of safe and effective EIS for GOV in a high-risk cirrhotic patient with hemophilia A.

Mandarins are picked by hand with the use of shears. An average mandarin picker makes at least 20,000 cuts daily. This daily workload on the upper limbs is the cause of occupational cervicobrachial disorders (OCD). In order to improve their working conditions, we devised two types of shears, one with a soft grip wrapped around the handle and another with shock reducing cushions in between the handles. The following two experiments were conducted. First we tested and compared the Borg scale and pinch meter scores of each participant by having them cut sticks as the same radius as those of mandarin stems using both the improved and conventional shears. Next, we placed two pressure sensors on each shear, where the middle finger and thumb contact the handles, to measure and compare the impact pressure within the hand. The results of the first experiment suggested that the improved shears reduces workload to the hand and fingers when comparing results to those of the conventional shears. The second experiment indicates that the shock reducing cushions reduces impact pressure to the hand from the handles when cutting.

Background: Argon plasma coagulation (APC) has been proven to be safe in vitro, and has been widely introduced to therapeutic endoscopy. We evaluated the thermal effects on esophageal or gastric wall in vivo, and its effectiveness as an adjunct to incomplete resection of early esophageal and gastric cancer after endoscopic mucosal resection (EMR). Methods: Thermal injuries were made using endoscopic APC irradiation in porcine esophagus and stomach under various conditions during general anesthesia, and depth of tissue damage was determined histopathologically. Patients with early gastric cancer (n = 24) and early esophageal cancer (n = 5) were treated with additional APC following microscopically incomplete EMR. APC was applied to coagulate the entire edge of EMR-induced ulcer 1 week after resection at power/gas settings of 50 W and 1.5 L/min in the stomach, and 40 W and 1.5 L/min in the esophagus for less than 5 s at each point. Results: Depth of tissue damage was related to pulse duration and power output. At power/gas settings of 60 W and 2.0 L/min, thermal damage extended across the submucosal layer with 5-s pulse duration in the stomach. Thermal damage with 5-s pulse duration at power/gas settings of 40 W and 2.0 L/min extended to the muscularis propria in the esophagus. In the clinical study of additional APC therapy, the recurrence rate was 6.9% (two of 29 cases). Conclusion: To avoid perforation, we recommend an APC power setting of 40–60 W for less than 5 s in the stomach and a lower power setting with shorter duration in the esophagus. APC seems to reduce recurrence of esophageal or gastric cancer after incomplete EMR.

During catheter exchange for percutaneous endoscopic gastrostomy (PEG), endoscopic or radiological observation is widely used to confirm that the catheter is placed correctly. However, to carry out these procedures in all patients at every catheter exchange costs time and money. It is therefore important to develop a reliable and safe method, which can also be used outside the clinic, to check the exchanged catheter. We examined the usefulness and safety of intragastric observation using a small-diameter rigid telescope, which can be inserted through the catheter lumen of a PEG tube.Before and after catheter exchange, observation was carried out using the rigid telescope E02700 (external diameter: 2.7 mm; Nisco Co., Tokyo, Japan). After air insufflation by the novel air-supplying adaptor, the rigid telescope was inserted through the button catheter for observation of the fistula and gastric lumen with guidewire introduction. Next, the old gastrostomy catheter was replaced by a new one, using the guidewire technique. Subsequently, the telescope was re-inserted to check the fistula and gastric lumen.With this technique, observation inside the stomach as well as inside the fistula was achieved without any complication during all 80 exchange trials in the 55 patients studied. A homemade adaptor was used effectively to convey air and water into the stomach during the observation.It is suggested that observation inside the stomach using a small-diameter rigid telescope at the time of gastrostomy exchange is useful and safe for checking the location of the newly fixed catheter.

Background To examine the effects of percutaneous endoscopic gastrostomy (PEG) on quality of life (QOL) in patients with dementia. Methods We retrospectively included 53 Japanese community and tertiary hospitals to investigate the relationship between the newly developed PEG and consecutive dementia patients with swallowing difficulty between Jan 1st 2006 and Dec 31st 2008. We set improvements in 1) the level of independent living, 2) pneumonia, 3) peroral intake as outcome measures of QOL and explored the factors associated with these improvements. Results Till October 31st 2010, 1,353 patients with Alzheimer’s dementia (33.1%), vascular dementia (61.7%), dementia with Lewy body disease (2.0%), Pick disease (0.6%) and others were followed-up for a median of 847 days (mean 805 ± 542 days). A total of 509 deaths were observed (mortality 59%) in full-followed patients. After multivariate adjustments, improvement in the level of independent living was observed in milder dementia, or those who can live independently with someone, compared with advanced dementia, characterized by those who need care by someone: Odds Ratio (OR), 3.90, 95% confidence interval (95%CI), 1.59 - 9.39, P = 0.003. Similarly, improvement of peroral intake was noticed in milder dementia: OR, 2.69, 95%CI, 1.17 - 6.17, P = 0.02. Such significant associations were not observed in improvement of pneumonia. Conclusions These results suggest that improvement of QOL after PEG insertion may be expected more in milder dementia than in advanced dementia.

AIM: To examine the long term survival of geriatric patients treated with percutaneous endoscopic gastrostomy (PEG) in Japan. METHODS: We retrospectively included 46 Japanese community and tertiary hospitals to investigate 931 consecutive geriatric patients (≥ 65 years old) with swallowing difficulty and newly performed PEG between Jan 1st 2005 and Dec 31st 2008. We set death as an outcome and explored the associations among patient’s characteristics at PEG using log-rank tests and Cox proportional hazard models. RESULTS: Nine hundred and thirty one patients were followed up for a median of 468 d. A total of 502 deaths were observed (mortality 53%). However, 99%, 95%, 88%, 75% and 66% of 931 patients survived more than 7, 30, 60 d, a half year and one year, respectively. In addition, 50% and 25% of the patients survived 753 and 1647 d, respectively. Eight deaths were considered as PEG-related, and were associated with lower serum albumin levels (P = 0.002). On the other hand, among 28 surviving patients (6.5%), PEG was removed. In a multivariate hazard model, older age [hazard ratio (HR), 1.02; 95% confidence interval (CI), 1.00-1.03; P = 0.009], higher C-reactive protein (HR, 1.04; 95% CI: 1.01-1.07; P = 0.005), and higher blood urea nitrogen (HR, 1.01; 95% CI: 1.00-1.02; P = 0.003) were significant poor prognostic factors, whereas higher albumin (HR, 0.67; 95% CI: 0.52-0.85; P = 0.001), female gender (HR, 0.60; 95% CI: 0.48-0.75; P < 0.001) and no previous history of ischemic heart disease (HR, 0.69; 95% CI: 0.54-0.88, P = 0.003) were markedly better prognostic factors. CONCLUSION: These results suggest that more than half of geriatric patients with PEG may survive longer than 2 years. The analysis elucidated prognostic factors.

内視鏡的ポリペクトミーを施行した大腸腺腫および早期癌205病変の検討を行った.1)腺腫,早期癌ともに年令では50-60歳台,性比では男性に多かった.2)205病変中腺腫は182病変,早期癌は23病変(m癌14,sm癌9)で早期癌は対象病変の11.2%を占めた.3)腺腫,早期癌ともにS状結腸,直腸,下行結腸の順に多く左側結腸にそれぞれ81.4%,95.7%が存在した.4)早期癌の対象病変に対する局在別比率は直腸の17。6%をはじめとし肛門側ほど高かった.5)腫瘍径別の早期癌比率は4mm以下では0%,5-9mmで3.2%,10-19mmで24.7%,20mm以上で40.0%と腫瘍径増大に伴ない増加した,sm癌は9mm以下では存在しなかった.6)腫瘍径を局在別にみると肛門側に行くに従いわずかに増大していたが,同一径では肛門側ほど癌化率が高い可能性が示唆された.7)形状は腺腫,早期癌ともに有茎,亜有茎,無茎の順に多かったが,早期癌比率は同一径に限ると有茎の方が低かった.

A case of bleeding duodenal varix which was treated successfully with endoscopic injection sclerotherapy (EIS) is reported. The patient developed a hemorrhage from a varix in the descending portion of the duodenum two months after EIS for esophageal varices, and hemostasis was achieved using EIS with an intravericeal injection of 1% polidocanol. The duodenal varix decreased in size after EIS. Two months after EIS, a splenectomy was performed. During a 14-month follow up period after the EIS for the duodenal varix, there was no recurrent bleeding.

We developed a bi-plane TV monitoring system using a TV endoscope (Electronic endoscope manufactured by Toshiba-Machida, Tokyo, Japan) that permits simultaneous display of real-time and prerecorded images. Various findings of the two examinations can be precisely compared using this system, and a detailed evaluation of the progress of peptic ulcers obtained. In addition, the effects of various endoscopic therapies can be accurately evaluated. In endoscopic injection sclerotherapy of esophageal varices, now varices (or recurrent varices) were differentiated. In laser therapy for early gastric cancer, precise delimitation of the lesion for radiation was possible, and the therapeutic effects were more accurately evaluated. These results show the diagnostic as well as therapeutic usefulness of this system. Furthermore, for the examination of the lower digestive tract, X-ray images were incorporated into this system. This is a useful modality for diagnostic and therapeutic procedures in colonic disease.