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The effect of molecular structure on the traction properties of polyglycol oils was investigated using a traction tester, and in-situ observation of the oil film was performed with a micro-Fourier transform infrared spectrometer under elastohydrodynamic lubrication conditions. The sample oils used were polypropylene glycol (PPG) diol, PPG triol, PPG dimethyl ether, PPG diester, PPG diamine, PPG triamine, and poly-α-olefin. The traction coefficient and oil film thickness of the sample oils were sensitive to the functional group at the terminal of the molecule. The sample oil containing polar functional group is larger in oil film thickness and traction coefficient than non-polar hydrocarbon oil, poly-α-olefin. These results suggest that the hydrogen bonding of functional groups was strengthened by high pressure in the Hertzian contact region. Moreover, the effect of water in the sample oils on the traction behavior was discussed. Water was dissolved into the sample oils from the atmosphere during the lubrication test, and it is implied that water in PPG diamine affect the traction coefficient.

In situ observation of lubricant films formed with greases was carried out at EHL conditions with a micro-FTIR. Three urea compounds were used as a thickener and 12 mass percent of the thickener was added in PAO, respectively. From the IR spectra, CH and NH stretching vibration peaks were observed from urea greases. The film thickness and the concentration of thickener were estimated from the absorbance of CH and the ratio of absorbance of NH and CH. Two-dimensional distribution of the thickness and the concentration around Hertzian contact was obtained at the resolution of 50 μm. The thickener of urea grease was concentrated on ball and disk surfaces. It was found that the concentrate on thickener at Hertzian contact region was dependent on thickener itself. Time dependence of the thickness and the concentration at Hertzian contact were obtained at the resolution of 45 s under shearing conditions. The film thickness of urea greases at Hertzian contact was greatly decreased by shearing and the film thickness and the concentration were recovered when the condition was changed to rolling. This behavior was supposed with detachment and growth of the adhered film of the thickener. Lubricating characteristics of urea greases were discussed based on the concentration of thickener at Hertzian contact.

Research interests recently increased in studying polymer-type friction modifiers (polymer FM) consisting of a polymer backbone and a functional group because of their good friction reduction capability. However, there is no clear verification of their working mechanisms. Therefore, the polymer FM behavior at the contact region must be understood to provide mechanistic information and design further-improved polymer FMs. For this purpose, in situ observation techniques have been applied to the chemical analysis of the oil film formed from a polymer FM using a micro-Fourier transform infrared spectrometer. The experimental results indicate that the polymer concentrations at the Hertzian contact drastically increased, exceeding the bulk concentration of oil. The following new friction reduction mechanism is proposed based on the clarified polymer FM concentration: the concentrated adsorption layer of the polymer FM prevents direct contact of the surface asperities.

This study investigates the effects of both, molecular structure and surface roughness, on the tribochemical decomposition of synthetic base oils under high-vacuum conditions. Nascent steel surfaces exhibit high activity to catalyze the decomposition of synthetic oil under lubricating conditions. Decomposition was performed on multiply alkylated cyclopentane (MAC) and alkyl diphenyl ether (ADE) at the nascent surface of bearing steel 52100 and was monitored by a ball-on-disk friction tester in a vacuum chamber attached to a quadrupole mass spectrometer. Although MAC decomposed, ADE did not decompose on the flat steel surface. Steel surfaces used within this experiment underwent procedural abrasion, providing the requisite roughness to generate the nascent steel surface for the friction test. Decomposition of ADE and desorption of benzene were observed in the presence of the nascent steel surface under friction. As the surface morphology of the pretreated roughened surfaces changed during friction, the contact pressure and plasticity of the surface decreased. We concluded that the tribochemical decomposition of ADE was accelerated on rough steel surfaces by the generation of a nascent surface at the point of metal-metal contact. From these results, the critical role of a nascent steel surface on the tribochemical decomposition of syntheticoils is discussed.

In situ observation of lubricant films formed with greases was performed with a micro Fourier transform infrared spectrometer (FT-IR) under elastohydrodynamic lubrication (EHL) conditions between a steel ball and a single-crystal silicon disk. Twelve mass percent of lithium stearate or aromatic-type urea compound were added as thickener to polyalphaolefin base oil. Peaks relating to CH, C=O and NH were monitored in the FT-IR analysis. The film thickness and the concentration of thickener were estimated from the absorbance of CH and the ratio of absorbance of C=O and CH. Two-dimensional distribution of the thickness and the concentration around EHL contact was obtained at a resolution of 50 μm. It was found that the concentration of thickener at EHL contact area was dependent on the type of thickener. Although the concentration of Li grease decreased at the EHL contact area, that of urea increased even at low entrainment speed. The thickener of urea grease was concentrated on the ball and the disk surfaces. The film thickness at EHL contact of each grease can be explained by the concentration of thickener at the contact. Lubricating characteristics of urea grease are discussed based on the concentration of thickener at the EHL contact.

The performance of wire drawing is closely dependent on lubrication between die and metal wire. The behavior of lubricants between the die and the wire plays an important role in the lubricating performance for wire drawing. Therefore, the lubricant behavior should be made clearer by a direct observation of the drawing interface in die. The objective of this work is to understand the behavior of lubricants based on the chemical reactions for wire drawing. The drawing properties of these lubricants are discussed on the basis of the generation of metal soap. In situ observation of lubricant film during wire drawing was carried out using a micro-Fourier transform infrared spectroscopy (FTIR). The infrared (IR) spectra of oil film between die and metal wire can be obtained and oil film shape and concentration of additive can be estimated. It was found that oleic acid as an additive reacts with metal wire chemically and metal soap was formed. The concentration of metal soap was distributed to be high at the end of reduction zone under the dynamic conditions.

Abstract Background Tracheobronchial injury in children is rare but can be highly fatal in severe cases. Therefore, prompt diagnosis and treatment are required. The appropriate treatment method depends on the extent and severity of the injury. Case presentation An 8-year-old girl fell from the fifth floor and was transported to a local hospital. She had a tracheobronchial injury, went into cardiopulmonary arrest during transportation to our hospital. She was revived with cardiopulmonary resuscitation, and veno-arterial extracorporeal membrane oxygenation (VA-ECMO) was commenced. Subsequently, we performed tracheobronchial reconstruction by inverted Barclay’s method for tracheobronchial injury. She was switched from VA-ECMO to venovenous (VV)-ECMO 4 days postoperatively, and VV-ECMO was eventually discontinued 27 days after the surgery. The patient was awake and weaned off the ventilator on postoperative day 58. She was discharged 97 days after the surgery. Conclusions Tracheobronchial reconstruction by inverted Barclay’s method is the preferred surgical technique when other reconstruction techniques are expected to cause excessive tension on the anastomosis of the right main bronchus.

Abstract Background The median sternotomy approach in sleeve pneumonectomy enables diseased lung ventilation in selected cases, which may reduce the difficulty in achieving anastomosis under intubation of the left main bronchus. However, with median sternotomy, the ascending aorta requires repeated mobilization to expose the operative field for anastomosis, which can cause an aortogenic embolic stroke. Case presentation A 70-year-old Asian man presenting 6 months after developing hemoptysis was diagnosed with right upper lobe lung cancer (stage T4N0M0), invading the lower trachea and basal bronchus. Preoperative computed tomography revealed ascending aorta calcification. Right sleeve pneumonectomy was performed using median sternotomy with diseased lung ventilation. The ascending aorta was repeatedly mobilized to adequately expose the tracheobronchial bifurcation. Surgery was uneventful, but he did not recover complete consciousness even after termination of anesthesia. Mild paralysis of both upper extremities was observed. Head magnetic resonance imaging on postoperative day 1 revealed multiple small acute infarctions in the brain, possibly caused by mobilization of the aorta. He received anticoagulation therapy and rehabilitation and was discharged on postoperative day 30. Conclusion The median sternotomy approach in sleeve pneumonectomy enables diseased lung ventilation. However, the possibility of aortogenic embolic stroke should be considered when calcification of the ascending aorta is observed on preoperative computed tomography.

Abstract Background Linalool, an acyclic monoterpene alcohol, is extensively used in the flavor and fragrance industries and exists as two enantiomers, (S)- and (R)-linalool, which have different odors and biological properties. Linalool extraction from natural plant tissues suffers from low product yield. Although linalool can also be chemically synthesized, its enantioselective production is difficult. Microbial production of terpenes has recently emerged as a novel, environmental-friendly alternative. Stereoselective production can also be achieved using this approach via enzymatic reactions. We previously succeeded in producing enantiopure (S)-linalool using a metabolically engineered Pantoea ananatis, a member of the Enterobacteriaceae family of bacteria, via the heterologous mevalonate pathway with the highest linalool titer ever reported from engineered microbes. Results Here, we genetically modified a previously developed P. ananatis strain expressing the (S)-linalool synthase (AaLINS) from Actinidia arguta to further improve (S)-linalool production. AaLINS was mostly expressed as an insoluble form in P. ananatis; its soluble expression level was increased by N-terminal fusion of a halophilic β-lactamase from Chromohalobacter sp. 560 with hexahistidine. Furthermore, in combination with elevation of the precursor supply via the mevalonate pathway, the (S)-linalool titer was increased approximately 1.4-fold (4.7 ± 0.3 g/L) in comparison with the original strain (3.4 ± 0.2 g/L) in test-tube cultivation with an aqueous-organic biphasic fermentation system using isopropyl myristate as the organic solvent for in situ extraction of cytotoxic and semi-volatile (S)-linalool. The most productive strain, IP04S/pBLAAaLINS-ispA*, produced 10.9 g/L of (S)-linalool in “dual-phase” fed-batch fermentation, which was divided into a growth-phase and a subsequent production-phase. Thus far, this is the highest reported titer in the production of not only linalool but also all monoterpenes using microbes. Conclusions This study demonstrates the potential of our metabolically engineered P. ananatis strain as a platform for economically feasible (S)-linalool production and provides insights into the stereoselective production of terpenes with high efficiency. This system is an environmentally friendly and economically valuable (S)-linalool production alternative. Mass production of enantiopure (S)-linalool can also lead to accurate assessment of its biological properties by providing an enantiopure substrate for study.

Objective: Precise prediction of postoperative pulmonary function is extremely important for accurately evaluating the risk of perioperative morbidity and mortality after major surgery for lung cancer. This study aimed to compare the accuracy of a single-photon emission computed tomography/computed tomography (SPECT/CT) method that we recently developed for predicting postoperative pulmonary function versus the accuracy of both the conventional simplified calculating (SC) method and the method using planar images of lung perfusion scintigraphy. Methods: The relationship between the postoperative observed % values of the forced expiratory volume in 1 second (FEV1) or diffusing capacity for carbon monoxide (DLCO or DLCO’) and the % predicted postoperative (%ppo) values of FEV1, DLCO, or DLCO’ calculated by the three methods were analyzed in 30 consecutive patients with lung cancer undergoing lobectomy. Results: The relationship between the postoperative observed % values and %ppo values calculated by the three methods exhibited a strong correlation (Pearson r>0.8, two-tailed p

Objective: We compared post-thoracotomy pain syndrome (PTPS) incidence in patients who underwent uniportal or multiportal video-assisted thoracoscopic surgery (VATS). Methods: We included 223 patients who underwent either uniportal or multiportal VATS between January 2017 and October 2018 (pulmonary lobectomies and pulmonary segmentectomies—uniportal: n=19, multiportal: n=133; wedge lung resections—uniportal: n=16, multiportal: n=55). We retrospectively studied incidences of PTPS in all subgroups. Results: Incidences of PTPS were significantly less for uniportal procedures for both the pulmonary lobectomy/segmentectomy group (P=0.024) and the wedge lung resection group (P=0.0315) than for multiportal procedures. Conclusion: Patients who underwent uniportal VATS procedures had lower incidences of PTPS than the multiportal VATS group. The uniportal VATS approach is therefore beneficial for patients.

PURPOSE:We developed an ex vivo lung CT (EVL-CT) technique that allows us to obtain detailed CT images and morphologically assess the retrieved lung from a donor for transplantation. After we recovered the lung graft from a brain-dead donor, we transported it to our hospital and CT images were obtained ex vivo before lung transplant surgery. The objective of this study was to investigate the correlation between the EVL-CT findings and post-transplant outcome in patients who underwent bilateral lung transplantation (BLT) or single lung transplantation (SLT). METHODS:We retrospectively reviewed the records of 70 patients with available EVL-CT data who underwent BLT (34 cases) or SLT (36 cases) in our hospital between October 2007 and September 2017. The recipients were divided into 2 groups (control group, infiltration group) according to the findings of EVL-CT of the lung graft in BLT and SLT, respectively. Recipients in the control group were transplanted lung grafts without any infiltrates (BLT control group, SLT control group). Recipients in the infiltration group received lung grafts with infiltrates (BLT infiltration group, SLT infiltration group). RESULTS:The recipients in the BLT infiltration group showed significantly slower recovery from primary graft dysfunction and a longer mechanical ventilation period and ICU stay period than those in the BLT control group. The mechanical ventilation period was significantly longer in the recipients in the SLT infiltration group than those in the SLT control group. CONCLUSION:EVL-CT may predict the outcome of the early phase after lung transplantation.

Background: There has been little research conducted regarding cognitive treatments for the elderly postsurgical population. Patients aged ≥60 years have an increased risk of postoperative cognitive decline, a condition in which cognitive functions are negatively affected. This cognitive decline can lead to a decline in quality of life. In order to maintain a high quality of life, the elderly postsurgical population may benefit from treatment to maintain and/or improve their cognitive functions. This pilot study investigates the effect of simple calculation and reading aloud (SCRA) cognitive training in elderly Japanese postsurgical patients.Methods: Elderly patients undergoing non-cardiovascular thoracic surgery under general anesthesia were recruited (n = 12). Subjects were randomly divided into two groups—one that receives 12 weeks of SCRA intervention, and a waitlisted control group. Before and after the intervention, we measured cognitive function [Mini-Mental Status Exam-Japanese (MMSE-J), Frontal Assessment Battery (FAB), computerized Cogstate Brief Battery (CBB)] and emotional state [General Health Questionnaire-12 (GHQ-12), Geriatric Depression Scale (GDS), Quality of Life Scale-5 (QOL-5)].Results: Group difference analyses using ANCOVA with permutation test showed that the intervention SCRA group had a significant improvement in FAB motor programming sub-score, GDS, and QOL-5 compared to the control group. Within-group analyses using Wilcoxon signed-rank test to compare baseline and follow-up showed that the SCRA intervention group total FAB scores, FAB motor programming sub-scores, and QOL-5 scores were significantly improved.Discussion: This pilot study showed that there are important implications for the beneficial effects of SCRA intervention on cognitive function and emotional state in the postoperative elderly population; however, further investigations are necessary to reach any conclusions.Trial registration: This study was registered with the University Hospital Medical Information Network (UMIN) Clinical Trial Registry (UMIN000019832).

Background: This pilot study investigated the effects of partial pulmonary lobectomy lung surgery on cognitive functions of elderly Japanese patients. It is recognized that elderly patients undergoing surgery have increased risk of Postoperative Cognitive Decline (POCD), a condition in which learning, memory, and processing speed is greatly reduced after surgery. Since elderly patients are more likely to exhibit symptoms of POCD, the incidence is increasing as the population receiving surgery is aging.Methods: Cognitive function was measured for all subjects (n = 12) before and after surgery using three different cognitive tests: Mini-Mental Status Exam-Japanese (MMSE-J), Frontal Assessment Battery (FAB), and a computerized Cogstate Brief Battery (CBB). Changes in these measures indicate changes in cognitive function. In addition, the 12-item General Health Questionnaire (GHQ-12), the Geriatric Depression Scale (GDS), and the 5-item Quality of Life questionnaire (QOL-5) were administered at each time point to measure mental and emotional state. Changes in outcome measures were analyzed via Wilcoxon signed-rank test. Exploratory correlation analysis was conducted using Spearman’s rho.Results: Data show a decline in detection (DET; p = 0.045) and identification (IDN; p = 0.038). Spearman’s correlation coefficient show a significant correlation between postoperative DET scores and postoperative IDN scores (ρ = 0.78, p = 0.005), a significant correlation between change in IDN and baseline GHQ-12 scores (ρ = -0.595, p = 0.027), and a significant correlation between change in one-back (OBK) scores and duration of anesthesia (ρ = -0.72, p = 0.012).Discussion: This was the first report to examine cognitive decline after major thoracic surgery in Japanese patients. Previous studies have evidenced that POCD is a common phenomenon after surgery, and that age is a major risk factor. The CCB measured significant change in two cognitive domains: attention and psycomotor function. This study clarified that decline in cognition is detectable in certain measures after thoracic surgery in the elderly Japanese patient population. Additionally, longer anesthetic exposure may negatively impact attention and working memory, and preoperative mental wellbeing is a possible predictor of POCD. These preliminary results have important implications and support the need for future studies.

We performed extremely low-energy 16O+ implantation at 10 keV (Rp ∼ 25 nm) followed by annealing aiming at directly synthesizing an ultrathin Si layer separated by a buried SiO2 layer in Si(001) substrates, and then investigated feasible condition of recrystallization and stabilization of the superficial Si and the buried oxide layer by significantly low temperature annealing. The elemental compositions were analyzed by Rutherford backscattering (RBS) and secondary ion mass spectroscopy (SIMS). The crystallinity of the superficial Si layer was quantitatively confirmed by ananlyzing RBS-channeling spectra. Cross-sectional morphologies and atomic configurations were observed by transmission electron microscope (TEM). As a result, we succeeded in directly synthesizing an ultrathin single-crystalline silicon layer with ≤20 nm thick separated by a thin buried stoichiometric SiO2 layer with ≤20 nm thick formed by extremely low-energy 16O+ implantation followed by surprisingly low temperature annealing at 1050∘ C.

Vasohibin-1 (VASH1) is isolated as an endothelial cell (EC)-produced angiogenesis inhibitor. We questioned whether VASH1 plays any role besides angiogenesis inhibition, knocked-down or overexpressed VASH1 in ECs, and examined the changes of EC property. Knock-down of VASH1 induced premature senescence of ECs, and those ECs were easily killed by cellular stresses. In contrast, overexpression of VASH1 made ECs resistant to premature senescence and cell death caused by cellular stresses. The synthesis of VASH1 was regulated by HuR-mediated post-transcriptional regulation. We sought to define the underlying mechanism. VASH1 increased the expression of (superoxide dismutase 2) SOD2, an enzyme known to quench reactive oxygen species (ROS). Simultaneously, VASH1 augmented the synthesis of sirtuin 1 (SIRT1), an anti-aging protein, which improved stress tolerance. Paraquat generates ROS and causes organ damage when administered in vivo. More VASH1 (+/-) mice died due to acute lung injury caused by paraquat. Intratracheal administration of an adenovirus vector encoding human VASH1 augmented SOD2 and SIRT1 expression in the lungs and prevented acute lung injury caused by paraquat. Thus, VASH1 is a critical factor that improves the stress tolerance of ECs via the induction of SOD2 and SIRT1.

The combined pulmonary fibrosis and emphysema (CPFE) was reported first in 1990, but it has been comparatively underestimated until recently. Although the diagnostic findings of both emphysematous and fibrotic regions are detectable by high-resolution computed tomography (HRCT) of the chest, the degree of progressive fibrosis, which increases with emphysematous lesions, is difficult to evaluate. In this study, we hypothesized that the biomarkers for pulmonary fibrosis, surfactant protein D (SP-D), and KL-6 would serve as good indicators of fibrotic lesions in CPFE. We recruited 46 patients who had been diagnosed in our hospital with both emphysema and fibrosis by their CT scan image from April 2003 to March 2008. The correlation among their pulmonary function tests, composite physiologic index (CPI), and the serum levels of SP-D and KL-6 was evaluated. We found a correlation between KL-6 and %VC, %TLC, or CPI and between SP-D and %VC or CPI. Interestingly, the combined product of KL-6 and SP-D (KL-6xSP-D) was found to highly correlate with %VC and %TLC or CPI. These results show that both KL-6 and SP-D, and especially the product of SP-D and KL-6, are good indicators of the presence of fibrotic lesions in the lungs of CPFE patients.