Bilayer membranes formed by phospholipids vary in their membrane states by undergoing phase transitions in response to various external environmental factors. Pressure is one of these important ...environmental factors, but there are very few studies on the effects of pressure on phospholipid bilayer membranes. It is possible to deepen our understanding of the membrane states of phospholipid bilayer membranes by combining information regarding temperature- and/or ligand-responsivity with that regarding pressure-responsivity. In this review, we thermodynamically characterize the bilayer phase transitions of three kinds of saturated glycerophospholipids, each with a different polar head group (phosphatidyl-ethanolamine (PE), -choline (PC) or -glycerol (PG)), and explain their various membrane states depending on temperature and pressure. Both temperature- and pressure-responsivity reveal inherent features of these bilayer membranes: the metastability of the gel phase for PE bilayer membranes, the polymorphism of the gel phases for PC bilayer membranes and morphological changes in bilayer aggregates for PG bilayer membranes.
Commercially available Pt metal catalysts supported on carbon black (Pt/CB) for polymer electrolyte fuel cell (PEFC) cathodes were covered with silica layers to improve their durability under the ...severe cathode operating conditions. The Pt metal particles in the Pt/CB catalyst grew in size during the accelerated durability tests (potential cycling between 0.6 and 1.0 V vs. RHE in an aqueous HClO4 electrolyte). Thus, the Pt/CB catalyst was seriously deactivated for the oxygen reduction reaction over the course of the durability tests. In contrast, the silica layers, which wrapped around the Pt metal particles in the silica-coated Pt/CB catalyst, prevented the migration of the Pt metal particles on the carbon supports and the diffusion of Pt cations out of the silica layers. Thus, the silica-coated Pt/CB catalysts maintained a high activity for the oxygen reduction reaction over the course of the durability tests. In addition, the silica-coated Pt/CB prepared from methyltriethoxysilane showed a higher activity than that prepared from tetraethoxysilane. The porous structures and hydrophobicity of silica prepared from methyltriethoxysilane promoted the diffusion of oxygen and water molecules in the silica layers of the silica-coated Pt catalysts.
•Coverage of Pt/CB cathode catalyst for PEFC with silica improves its durability.•Hydrophobic silica promotes the diffusion of water and oxygen.•Small pores in silica prevents the diffusion of Pt cations out of silica.
To clarify the impact of blood pressure (BP) management ranges on pregnancy outcomes, we conducted a multicenter retrospective analysis of 215 women with singleton pregnancies diagnosed with ...essential hypertension either before or within 14 weeks of gestation. Patients were classified according to systolic BP (sBP; <130, 130-139, 140-159, and ≥160 mmHg) or diastolic BP (dBP; <80, 80-89, 90-109, and ≥110 mmHg) at 8-11, 12-15, and 16-19 weeks of gestation. The risk of early-onset superimposed preeclampsia and small-for-gestational-age neonates was assessed in each BP group. Moreover, a subgroup analysis was performed in 144 eligible patients whose BP was measured at both 12-13 and 14-15 weeks of gestation. At 16-19 weeks of gestation, higher sBP significantly increased the incidence of early-onset superimposed preeclampsia (13.3%, 24.6%, 32.2% and 75.0%, respectively) and small-for-gestational-age neonates (6.0%, 13.1%, 16.9% and 50.0%, respectively). Multivariate logistic regression analyses showed that women with sBP < 130 mmHg at 16-19 weeks of gestation had a significantly lower risk of early-onset superimposed preeclampsia than women with sBP of 140-159 mmHg. Subgroup analyses also showed that even at 14-15 weeks of gestation, sBP < 130 mmHg was associated with a significantly lower risk of early-onset superimposed preeclampsia than an sBP of 140-159 mmHg. In conclusion, sBP < 130 mmHg within 14 weeks of gestation reduced the risk of developing early-onset superimposed preeclampsia in women with chronic hypertension.
Background
Considering advances in current post-recurrence treatment, we examined the prognostic significance of the number of risk factors for loss-of-exercise capacity (LEC) after lung cancer ...surgery, which were identified by our previous prospective observational study.
Methods
Risk factors for LEC were defined as a short baseline 6-min walk distance (<400 m), older age (≥75 years), and low predicted postoperative diffusing capacity for carbon monoxide (<60%). Patients were classified as Risk 0/I/II/III according to the number of risk factors. The survival data were retrospectively analyzed.
Results
Between 2014 and 2017, 564 patients (
n
= 307, 193, 57, 7; Risk 0/I/II/III) who underwent lung cancer surgery were included in the study. The number of risk factors was associated with smoking status, predicted postoperative forced expiratory volume in 1 s, histology, pathological stage, and adjuvant therapy. In a multivariate Cox regression analysis, compared to Risk 0, Risk I/II/III showed significant associations with overall survival (hazard ratios: 1.92, 3.35, 9.21; 95% confidence interval: 1.27–2.92, 2.01–5.58, 3.64–23.35; Risk I/II/III, respectively). In 141 patients with recurrence, molecular targeted therapies (MTTs) or immune checkpoint inhibitors (ICIs) were included in 58%, 47%, 32%, and 0% (Risk 0/I/II/III) during the course of treatment. In patients with MTT/ICI treatment, the estimated 1-year and 3-year post-recurrence survival rates were 88% and 58%, respectively.
Conclusions
Risk classification for LEC was associated with survival after lung cancer surgery, as well as post-recurrence treatment. The concept of physical performance-preserving surgery may contribute to improving the outcomes of current lung cancer treatment.
Background
Psoas muscle mass is a surrogate marker for sarcopenia: a depletion of skeletal muscle mass. This study was conducted to elucidate the prognostic significance of the psoas muscle index ...(PMI: cross-sectional area of the bilateral psoas muscle at the umbilical level on computed tomography/height
2
cm
2
/m
2
) in patients undergoing surgery for lung squamous cell carcinoma (SCC) and lung adenocarcinoma (ADC).
Methods
One hundred and sixty-five patients with SCC and 556 patients with ADC who underwent R0 resection between 2007 and 2014 were reviewed for analysis. In SCC patients, the mean value (standard deviation) of the PMI was 6.15 (1.49) in men and 4.65 (1.36) in women. Among ADC patients, the PMI was 7.12 (1.60) in men and 5.29 (1.22) in women. Clinicopathological characteristics as well as the survival were evaluated.
Results
The PMI was associated with the age, body mass index (BMI), and serum albumin. In the multivariable Cox regression analysis, after adjusting for age, BMI, serum albumin, sex, pathological stage, and diffusing capacity for carbon monoxide, the PMI showed a significant association with the overall survival (OS) and disease-free survival (DFS) in SCC patients (hazard ratios 0.50 and 0.56, 95% confidence intervals 0.39–0.65 and 0.45–0.71, respectively). On the other hand, in ADC patients, the PMI had no impact on the OS or DFS.
Conclusions
The PMI was significantly associated with the survival of lung SCC patients, but not of lung ADC patients, suggesting the presence of a previously unidentified relationship between skeletal muscle and lung SCC progression.
Background
The optimal management of an aberrant artery in pulmonary sequestration (PS) is controversial. Several studies have shown that hybrid surgery with preoperative coil embolization for an ...aberrant artery and surgical resection of the sequestrated lung is effective. However, there are no clear indications for the procedure.
Case presentation
A 68-year-old woman without any complaints was diagnosed with right intralobar PS, which was supplied by an aberrant artery from the thoracic aorta, via computed tomography performed during a medical examination. In addition, lung adenocarcinoma was detected over the border between the right upper and middle lobes. Preoperative coil embolization was performed by an interventional radiologist the day before surgery to decrease the risk of severe intraoperative hemorrhage. On the following day, bi-lobectomy of the right upper and middle lobes for lung adenocarcinoma with systemic lymph node dissection and segmentectomy of the sequestrated lung with thoracotomy was performed. Although no active hemorrhage was observed during surgery, the aberrant artery was challenging to dissect using an energy device due to the presence of an intravascular coil. Eventually, the coil stump was exposed, and it was cut with scissors. The postoperative course was uneventful.
Conclusions
We reported the pitfall of the hybrid surgery for intralobar PS. Preoperative coil embolization can prevent fatal intraoperative hemorrhage. If embolization is performed using a coil for an aberrant artery supplied from the thoracic aorta, where and how to dissect the aberrant artery should be cautiously determined based on preoperative images, with consideration of the presence of an intravascular coil.
Bilayers formed by phospholipids are frequently used as model biological membranes in various life science studies. A characteristic feature of phospholipid bilayers is to undergo a structural change ...called a phase transition in response to environmental changes of their surroundings. In this review, we focus our attention on phase transitions of some major phospholipids contained in biological membranes, phosphatidylcholines (PCs), depending on temperature and pressure. Bilayers of dipalmitoylphosphatidylcholine (DPPC), which is the most representative lipid in model membrane studies, will first be explained. Then, the bilayer phase behavior of various kinds of PCs with different molecular structures is revealed from the temperature-pressure phase diagrams, and the difference in phase stability among these PC bilayers is discussed in connection with the molecular structure of the PC molecules. Furthermore, the solvent effect on the phase behavior is also described briefly.
Abstract
OBJECTIVES
Since survival after postoperative non-small-cell lung cancer (NSCLC) recurrence is extremely poor, the long-term post-recurrence outcomes are not well understood. The purpose of ...this study was to evaluate the long-term post-recurrence outcomes and clarify who are possibly ‘cured’ in recent clinical practice.
METHODS
We reviewed the medical records of 635 patients who developed postoperative recurrence until 2012 after R0 resection for pathological Stage IA–IIIA NSCLC between 1993 and 2006. Factors associated with post-recurrence survival (PRS) and the characteristics of the long-term (≥5 years) survivors were analysed retrospectively.
RESULTS
The 5-year PRS rate of all 635 patients was 13%. Multivariable analysis revealed that female hazard ratio (HR) = 0.78, adenocarcinoma (HR = 0.77), locoregional (only) recurrence (HR = 0.59) and longer recurrence-free survival (HR = 0.99) were favourably associated with PRS. A total of 51 patients achieved 5-year PRS; however, 32 (63%) were cancer-bearing patients in their fifth post-recurrent year who were mainly treated by epidermal growth factor receptor–tyrosine kinase inhibitor (EGFR-TKI). Subsequent PRS curves for cancer-controlled and cancer-bearing groups were different (8-year PRS: 94% vs 31%, P = 0.003). Among 19 cancer-controlled patients in their fifth post-recurrent year, 17 (89%) patients initially received radical local therapy for their recurrence.
CONCLUSIONS
Two-thirds of 5-year survivors after postoperative NSCLC recurrence had a cancer-bearing status and showed deteriorated subsequent survival. Curability of postoperative NSCLC recurrence should be evaluated in terms of the ‘cancer-controlled’ status, and ‘cured’ population is included in the patients who are ‘cancer controlled’ at the fifth post-recurrent year.
Prodan (6-propiponyl-2-(
,
-dimethylamino)naphthalene) is well known as a polarity-sensitive fluorescent probe and has a high capability of detecting structural changes occurring within phospholipid ...bilayer membranes. In this study, we carried out the fluorescence spectroscopic observation of bilayer phase behavior for a series of symmetric saturated diacylphosphatidylcholines (C
PCs) with different acyl-chain length
(
= 12-15 and 19-22) using Prodan as a membrane probe to confirm the availability of Prodan along with the previous results for the C
PC bilayer membranes (
= 16-18). The results were discussed by constructing spectral three-dimensional (3D) imaging plots for visualizing the change in bilayer phase states with temperature or pressure to verify the functionality of this 3D imaging plot. It was found that the Prodan fluorescence technique is applicable to the detection of the changes in the bilayer phase states of all C
PCs with a few exceptions. One of the most crucial exceptions was that Prodan cannot be used for the detection of the bilayer-gel state of the C21PC bilayer membrane. It was also found that it is only to the C
PC bilayer membranes with
= 15-18 that the 3D imaging plot is adequately and accurately applicable as a useful graphical tool for visually detecting the bilayer phase states. This is a disadvantageous feature of this technique brought about by the high sensitivity of Prodan as a membrane probe. Further detailed studies on the molecular behavior of Prodan will enable us to find a more useful way of utilizing this membrane probe.
Purpose To identify the lumbar loading movements necessary in clinical practice. Participants and Methods A questionnaire survey was conducted among physical and occupational therapists in Japan. ...There were no exclusion criteria regarding the number of years of experience, age, or field of employment. The participants were randomly selected and administered the questionnaire. They were asked to list and rank the lumbar loadings they considered necessary. Results A total of 739 respondents participated in the survey. The results of this nationwide survey indicated that the lifting movement of heavy objects in the trunk flexion position was the most common movement (for 354 participants). Conclusion The main loading movements of the lumbar spine were reported to be heavy lifting movements (in the trunk flexion position) and trunk rotation movements. As perspectives, we aim to conduct an analytical study of some of lumbar spine loading movements outlined in this study, using a musculoskeletal simulator and electromyography.
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