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Numerous reported bioinspired osmotic energy conversion systems employing cation‐/anion‐selective membranes and solutions with different salinity are actually far from the biological counterpart. The iso‐osmotic power generator with the specific ionic permselective channels (e.g. K+ or Na+ channels) which just allow specific ions to get across and iso‐osmotic solutions still remain challenges. Inspired by nature, we report a bioinspired K+‐channel by employing a K+ selective ligand, 1,1,1‐tris{[(2′‐benzylaminoformyl)phenoxy]methyl}ethane (BMP) and graphene oxide membrane. Specifically, the K+ and Na+ selectivity of the prepared system could reach up to ≈17.8, and the molecular dynamics simulation revealed that the excellent permselectivity of K+ mainly stemmed from the formed suitable channel size. Thus, we assembled the K+‐selective iso‐osmotic power generator (KSIPG) with the power density up to ≈15.1 mW/m2 between equal concentration solutions, which is higher than traditional charge‐selective osmotic power generator (CSOPG). The proposed strategy has well shown the realizable approach to construct single‐ion selective channels‐based highly efficient iso‐osmotic energy conversion systems and would surely inspire new applications in other fields, including self‐powered systems and medical materials, etc. [ABSTRACT FROM AUTHOR]

Numerous reported bioinspired osmotic energy conversion systems employing cation‐/anion‐selective membranes and solutions with different salinity are actually far from the biological counterpart. The iso‐osmotic power generator with the specific ionic permselective channels (e.g. K+ or Na+ channels) which just allow specific ions to get across and iso‐osmotic solutions still remain challenges. Inspired by nature, we report a bioinspired K+‐channel by employing a K+ selective ligand, 1,1,1‐tris{[(2′‐benzylaminoformyl)phenoxy]methyl}ethane (BMP) and graphene oxide membrane. Specifically, the K+ and Na+ selectivity of the prepared system could reach up to ≈17.8, and the molecular dynamics simulation revealed that the excellent permselectivity of K+ mainly stemmed from the formed suitable channel size. Thus, we assembled the K+‐selective iso‐osmotic power generator (KSIPG) with the power density up to ≈15.1 mW/m2 between equal concentration solutions, which is higher than traditional charge‐selective osmotic power generator (CSOPG). The proposed strategy has well shown the realizable approach to construct single‐ion selective channels‐based highly efficient iso‐osmotic energy conversion systems and would surely inspire new applications in other fields, including self‐powered systems and medical materials, etc. [ABSTRACT FROM AUTHOR]

A novel enzyme-responsive supramolecular polysaccharide assembly composed of disulfide linked adamantane–naphthalimide fluorescent camptothecin prodrug (AdaCPT) and β-CD modified hyaluronic acid (HACD) was constructed, possessing low cellular cytotoxicity and exhibiting targeted cellular imaging and controlled drug release at specific sites while providing a concurrent means for the real-time tracking of drug delivery. [ABSTRACT FROM AUTHOR]

A pH-responsive and targeted polysaccharide conjugate was fabricated from the boronate linkage of N-(2-aminoethyl)-gluconamide-grafted hyaluronic acid with anticancer drug bortezomib, which could exhibit targeted drug release behaviors at acidic pH and possess lower cytotoxicity and a higher inhibition effect toward cancer cells. [ABSTRACT FROM AUTHOR]

Agrochemicals are widely used in agricultural production, but they may cause agrochemicals residues and environmental pollution. Polysaccharide-based materials have emerged as a promising biopolymer carrier for agrochemicals delivery. Herein, an eco-friendly, photo-responsive supramolecular polysaccharide hybrid hydrogels (HA-AAP-Guano-CD@LP) was constructed from arylazopyrazole-modified hyaluronic acid (HA-AAP), guanidinium functionalized β-cyclodextrin (Guano-CD), and laponite clay (LP) via synergistic host-guest and electrostatic interactions, which could realize the controlled release of plant growth regulators such as naphthalene acetic acid (NAA) and gibberellin (GA) and promote the growth of Chinese cabbage and alfalfa. More interestingly, after releasing the cargo, the hydrogels could be used to capture heavy metal ions via strong complexation between the ions and carboxyl groups. This polysaccharide-based supramolecular hybrid hydrogels may provide a new strategy to realize the precision agriculture by the controlled delivery of plant growth regulators and synergetic adsorption of pollutants. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Es-GC×GC-TOFMS approach to separate chiral volatiles in tea was established. • Volatile enantiomers in Wuyi rock teas from four cultivars were firstly quantitated. • Limits of quantitation of linalool oxides A−B in teas were as low as 0.2 pg/mL. • R -α-Ionone, S -(E)-nerolidol etc. were the potential markers to distinguish cultivar. • 7 Volatile enantiomers were identified as aroma-active compounds in Wuyi rock teas. Chiral volatiles play important roles in the formation of aroma quality of foods. To date, enantiomeric characteristics of chiral volatiles in Wuyi rock tea (WRT) and their aroma contributions are still unclear. In this study, an efficient enantioselective comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (Es-GC × GC-TOFMS) approach to separate and precisely quantitate 24 pairs of chiral volatiles in WRTs was established, and the enantiomeric distribution and aroma contribution of chiral volatiles among WRTs from four representative cultivars were investigated. Enantiomeric ratio (ER) of R -α-ionone (80%) in Dahongpao (DHP), ER of S -α-terpineol (57%) in Jinfo (JF), ERs of R -γ-heptanolactone (69%), S -γ-nonanolactone (55%), (2 R , 5 S)-theaspirane B (91%), concentration of S -(E)-nerolidol (313.37 ng/mL) in Rougui (RG) and concentration of R -α-ionone (33.01 ng/mL) in Shuixian (SX) were unique from other types of WRTs, which were considered as the potential chemical markers to distinguish WRT cultivars. The OAV assessment determined 7 volatile enantiomers as the aroma-active compounds, especially R -α-ionone and R -δ-octanolactone in SX, as well as S -(E)-nerolidol and (1 R , 2 R)-methyl jasmonate in RG contribute much to aroma formation of the corresponding WRTs. The above results provide scientific references for discrimination of tea cultivars and directed improvement of the aroma quality of WRT. [ABSTRACT FROM AUTHOR]

[Display omitted] • The 5 active components in notopterygium and its processed products were determined by MLC for the first time. • The isocratic chromatographic conditions were optimized through Box-Behnken design. • The established MLC method is simple, efficient, and low-cost. This work has developed an isocratic micellar liquid chromatographic method for simultaneous determination of nodakenin, isoimperatorin, psoralen, ferulic acid, and chlorogenic acid in notopterygium and notopterygium processed products for the first time. Analytes were successfully separated within 15 min. The optimized chromatographic conditions were obtained by Box-Behnken design optimization, and the mobile phase consisted of 0.064 M sodium lauryl sulfate aqueous solution and 8.15% n-pentanol with a pH value of 3.04. The analytes were eluted isocratically through a C18 column at a flow rate of 1 mL/min. The linear ranges, limit of detection, limit of quantitation, recovery, intra-day and inter-day precision of the proposed method were validated according to ICH guidelines. The proposed method was successfully applied to the quantitative the 5 active components in notopterygium and its processed products. It is a simple, efficient, and low-cost analytical method that provides an alternative method for the determination of the 5 active ingredients in notopterygium. [ABSTRACT FROM AUTHOR]

A multicomponent supramolecular nanoparticle composed of a polysaccharide–quantum dot conjugate was successfully constructed using a ligand-exchange method, which possessed low cellular cytotoxicity and showed controlled DNA condensation and targeted cellular imaging abilities toward cancer cells. [ABSTRACT FROM AUTHOR]

Background: In-stent restenosis (ISR) remains a common life-threatening complication and some studies have shown that pioglitazone can reduce the incidence of ISR in patients with drug-eluting stents (DES) implantation. We conducted a meta-analysis to assess the effect of pioglitazone in preventing ISR after DES implantation. Methods: Randomized controlled trials (RCTs) investigating the effects of pioglitazone for ISR after DES implantation were identified by systematic searches of multiple online databases and manual searches of related reference lists of identified trials through May 2014. The primary endpoint was the rate of ISR. Secondary endpoints included minimum lumen diameter, percentage stenosis of stented vessels, late loss, in-stent neointimal volume, target vessel revascularization (TVR), target lesion revascularization, myocardial infarction, stent thrombosis and death. Results: Five studies, comprising 255 pioglitazone-treated patients and 245 controls, were identified in the current meta-analysis. Pioglitazone did not significantly reduce the rate of ISR (P = 0.20) with low heterogeneity (I2 = 13.3%, P = 0.32). For the secondary outcomes, pioglitazone did not substantially affect the pooled estimates of these endpoints except late loss (P = 0.01) and TVR (P = 0.04). Conclusions: The limited evidence indicates that pioglitazone does not demonstrate markedly beneficial effect in patients subjected to coronary DES implantation. However, the results should be interpreted with care given the small sample size. Further large-scale RCTs are needed. [ABSTRACT FROM AUTHOR]

Abstract: Temozolomide (TM) has anti-tumor activity in patients with malignant glioma. Implantable poly (d,l-lactide-co-glycolide) (PLGA) microparticles of TM (TM–MS) have been developed, enhancing the cytotoxicity of TM to Glioma C6 cells . Vatalanib, as anti-angiogenic agent, has also shown anti-tumor activity with malignant gliomas . We examined the combined effects of TM–MS and vatalanib in a rat orthotopic glioma model and found TM–MS offered a greater tumor inhibition than TM, and combination treatment with both of them improved the survival time versus single agent therapy. The combination treatment also demonstrated an inhibition to rat glioma tumors, a significant decrease in cell proliferation, an increase in apoptosis, and a lower microvessel density within the glioma tumors. The results suggest that TM–MS can more effectively inhibit tumor than TM, and combination treatment with TM–MS and vatalanib inhibits tumor growth and angiogenesis and may prove to be a promising therapy for malignant gliomas. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, composite fluorocarbon/ZnO films were prepared by R.F. sputtering used polytetrafluoroethylene (PTFE) and Zn target on polyethylene terephthalate (PET) substrate. Argon was used as the working gas and oxygen used as reacting gas. The obtained films were characterized by means of SEM, XPS and UV–visible spectrophotometer. It was found, the surface morphology of composite fluorocarbon/ZnO films vary as the deposited time of ZnO. The growing mode of composite films is the deposition and expansion. The ultraviolet absorbance of composite fluorocarbon/ZnO films is equal to that of fluorocarbon films'' when deposited time of ZnO is within 2 min, while distinctively increases when deposited time of ZnO exceeds 5 min, the absorbance value is larger than the ZnOs''. The composite films exhibit multi-enhanced ultraviolet absorption due to π-conjugated molecular structure, nanoparticle-pore reflection and the absorption effect of nanosized ZnO particles. [Copyright &y& Elsevier]

Summary: Resistance to every family of clinically used antibiotics has emerged, and there is a pressing need to explore unique antibacterial targets. Wall teichoic acids (WTAs) are anionic polymers that coat the cell walls of many Gram-positive bacteria. Because WTAs play an essential role in Staphylococcus aureus colonization and infection, the enzymes involved in WTA biosynthesis are proposed to be targets for antibiotic development. To facilitate the discovery of WTA inhibitors, we have reconstituted the intracellular steps of S. aureus WTA biosynthesis. We show that two intracellular steps in the biosynthetic pathway are different from what was proposed. The work reported here lays the foundation for the discovery and characterization of inhibitors of WTA biosynthetic enzymes to assess their potential for treating bacterial infections. [Copyright &y& Elsevier]

Sawdust, a relatively abundant and inexpensive material is currently being investigated as an adsorbent to remove contaminants from water. Chemical substances including dyes, oil, toxic salts and heavy metals can be removed very effectively with the organic material. This article presents a brief review on the role of sawdust in the removal of contaminants. Studies on the adsorption of various pollutants by different sawdust materials are reviewed and the adsorption mechanism, influencing factors, favorable conditions, etc. discussed in this paper. Some valuable guidelines can be drawn for either scientific research or industrial design. [Copyright &y& Elsevier]

A multiple luminescence colors system was facile constructed based on the supramolecular assembly of anionic β-cyclodextrin, dodecayltrimethylaminium bromide (DTAB), a naphthalimide dye (G 1) and a benzothiadiazole derivative (G 2). Significantly, the fabricated system exhibited highly efficient energy transfer from G 1 to G 2 , accompanying by fluorescence color change from blue to yellow, including white light. Furthermore, the white light emission supramolecular assembly was constructed from anionic cyclodextrin with low degree of substitution and DTAB exhibited reversible temperature responsiveness with fluorescent color changes from white to yellow. Image 1 [ABSTRACT FROM AUTHOR]

Background: Vitamin D deficiency has been shown to be closely associated with peritoneal dialysis (PD)-related peritonitis. The aim of this study is to examine the feasibility of conducting a large, powered randomized controlled trial to determine the effects of vitamin D supplementation on the risk of PD-related peritonitis in patients who have already experienced an episode of peritonitis.Methods: This prospective, open-label randomized controlled pilot trial with blinded end-points aims to determine the feasibility of oral vitamin D supplementation and to explore its effects on the risk of subsequent PD-related peritonitis among PD patients who have recovered from a recent episode of peritonitis. Eligible patients will be randomized 1:1 to either oral vitamin D supplementation (2000 IU per day; intervention group) or no vitamin D supplementation (control group) in addition to usual care according to International Society for Peritoneal Dialysis guidelines. The sample size will be 30 patients for both groups. All participants will be followed for 12 months. The primary outcome is the assessment of feasibility (recruitment success, retention, adherence, safety) and fidelity (change in serum 25-hydroxyvitamin D level during follow-up) for a large, powered randomized controlled trial to determine the effects of vitamin D on the risk of PD-related peritonitis in the future. Secondary outcomes include time to peritonitis occurrence, recovery of peritonitis, peritonitis-related transition to hemodialysis, and peritonitis-related death (defined as death within 30 days of peritonitis onset).Discussion: This is the first randomized controlled trail investigating the effects of vitamin D supplementation on the risk of subsequent PD-related peritonitis among patients on PD. The findings for this pilot study will determine the feasibility of conducting a full-scale randomized controlled trail, which may provide a new strategy for preventing PD-related peritonitis among PD patients.Trial Registration: Clinicaltrails.gov, NCT03264625. Registered on 29 August 2017. [ABSTRACT FROM AUTHOR]

Bacillus subtilis shows high contamination and antibiotic resistance in the food industry due to their biofilm‐forming capacity. This study aimed to search a biopreservative to inhibit the biofilm formation of B. subtilis. The effect of garlic extracts, nisin, ε‐polylysine, and citric acid on bacterial growth, cell surface hydrophobicity, and cell morphology were observed to provide insight into the antibiofilm mechanisms. Results showed that nisin, ε‐polylysine, and citric acid completely inhibited the growth and biofilm formation of B. subtilis at 0.15, 0.09, and 1.5 mg/ml, respectively. Garlic extracts inhibited cell elongation, but cannot completely inhibit the biofilm formation even at 1.8 mg/ml. The antibiofilm activities of four biopreservatives were due to antibacterial activities, reduction in extracellular polymeric substances production, and cell surface hydrophobicity. Among these four biopreservatives, ε‐polylysine, which caused cell to collapse, had the highest antibacterial and antibiofilm activities followed by nisin, citric acid, and garlic extracts. Practical applications: Bacillus subtilis shows high contamination and antibiotic resistance due to their biofilm‐forming capacity. Finding a biopreservative to inhibit the growth and biofilm formation of B. subtilis was important in food industry. This study could pave the way for controlling B. subtilis in planktonic and biofilm states. [ABSTRACT FROM AUTHOR]

PIWI‐interacting RNAs (piRNAs) are highly expressed in various cardiovascular diseases. However, their role in cardiomyocyte death caused by ischemia/reperfusion (I/R) injury, especially necroptosis, remains elusive. In this study, a heart necroptosis‐associated piRNA (HNEAP) is found that regulates cardiomyocyte necroptosis by targeting DNA methyltransferase 1 (DNMT1)‐mediated 5‐methylcytosine (m5C) methylation of the activating transcription factor 7 (Atf7) mRNA transcript. HNEAP expression level is significantly elevated in hypoxia/reoxygenation (H/R)‐exposed cardiomyocytes and I/R‐injured mouse hearts. Loss of HNEAP inhibited cardiomyocyte necroptosis and ameliorated cardiac function in mice. Mechanistically, HNEAP directly interacts with DNMT1 and attenuates m5C methylation of the Atf7 mRNA transcript, which increases Atf7 expression level. ATF7 can further downregulate the transcription of Chmp2a, an inhibitor of necroptosis, resulting in the reduction of Chmp2a level and the progression of cardiomyocyte necroptosis. The findings reveal that piRNA‐mediated m5C methylation is involved in the regulation of cardiomyocyte necroptosis. Thus, the HNEAP‐DNMT1‐ATF7‐CHMP2A axis may be a potential target for attenuating cardiac injury caused by necroptosis in ischemic heart disease. [ABSTRACT FROM AUTHOR]

Interrogation of subcellular biological dynamics occurring in a living cell often requires noninvasive imaging of the fragile cell with high spatiotemporal resolution across all three dimensions. It thereby poses big challenges to modern fluorescence microscopy implementations because the limited photon budget in a live-cell imaging task makes the achievable performance of conventional microscopy approaches compromise between their spatial resolution, volumetric imaging speed, and phototoxicity. Here, we incorporate a two-stage view-channel-depth (VCD) deep-learning reconstruction strategy with a Fourier light-field microscope based on diffractive optical element to realize fast 3D super-resolution reconstructions of intracellular dynamics from single diffraction-limited 2D light-filed measurements. This VCD-enabled Fourier light-filed imaging approach (F-VCD), achieves video-rate (50 volumes per second) 3D imaging of intracellular dynamics at a high spatiotemporal resolution of ~180 nm × 180 nm × 400 nm and strong noise-resistant capability, with which light field images with a signal-to-noise ratio (SNR) down to -1.62 dB could be well reconstructed. With this approach, we successfully demonstrate the 4D imaging of intracellular organelle dynamics, e.g., mitochondria fission and fusion, with ~5000 times of observation. A super-resolution light-field imaging method enables video-rate 3D imaging of intracellular dynamics beyond diffraction limit and with strong noise-resistant capability. [ABSTRACT FROM AUTHOR]

Blood‐based tumor liquid biopsies are promising as an alternative or complement to tissue biopsies due to their noninvasiveness, convenience, and safety, and there is still a great demand for the discovery of new biomarkers for these biopsies. Here, nanoscale distribution patterns of subcellular structures in platelets, as imaged by structured illumination superresolution fluorescence microscopy, as a new type of potential biomarker for tumor liquid biopsies are presented. A standardized protocol for platelet sample preparation and developed an automated high‐throughput image analysis workflow is established. The diagnostic capability based on the statistical analysis of 280 000 superresolution images of individual platelets from a variety of tumor patients, benign mass patients, and healthy volunteers (n = 206) is explored. These results suggest that the nanoscale distribution patterns of α‐granules in platelets have the potential to be biomarkers for several cancers, including glioma and cervical, endometrial, and ovarian cancers, facilitating not only diagnosis but also therapeutic monitoring. This study provides a promising novel type of platelet parameter for tumor liquid biopsies at the subcellular level rather than the existing cellular or molecular level and opens up a new avenue for clinical applications of superresolution imaging techniques. [ABSTRACT FROM AUTHOR]

Background: Emerging research has reported that circular RNAs (circRNAs) play important roles in cardiac cell death after myocardial ischemia and reperfusion (I/R). Ferroptosis, a new form of cell death discovered in recent years, has been proven to participate in the regulation of myocardial I/R. This study used circRNA sequencing to explore the key circRNA in the regulation of cardiac ferroptosis after I/R and study the mechanisms of potential circRNA function. Methods: We performed circRNA sequencing to explore circRNAs differentially expressed after myocardial I/R. We used quantitative polymerase chain reactions to determine the circRNA expression in different tissues and detect the circRNA subcellular localization in the cardiomyocyte. Gain- and loss-of-function experiments were aimed to examine the function of circRNAs in cardiomyocyte ferroptosis and cardiac tissue damage after myocardial I/R. RNA pull-down was applied to explore proteins interacting with circRNA. Results: Here, we identified a ferroptosis-associated circRNA (FEACR) that has an underlying regulatory role in cardiomyocyte ferroptosis. FEACR overexpression suppressed I/R-induced myocardial infarction and ameliorated cardiac function. FEACR inhibition induces ferroptosis in cardiomyocytes and FEACR overexpression inhibits hypoxia and reoxygenation-induced ferroptosis. Mechanistically, FEACR directly bound to nicotinamide phosphoribosyltransferase (NAMPT) and enhanced the protein stability of NAMPT, which increased NAMPT-dependent Sirtuin1 (Sirt1) expression, which promoted the transcriptional activity of forkhead box protein O1 (FOXO1) by reducing FOXO1 acetylation levels. FOXO1 further upregulated the transcription of ferritin heavy chain 1 (Fth1), a ferroptosis suppressor, which resulted in the inhibition of cardiomyocyte ferroptosis. Conclusions: Our finding reveals that the circRNA FEACR-mediated NAMPT-Sirt1-FOXO1-FTH1 signaling axis participates in the regulation of cardiomyocyte ferroptosis and protects the heart function against I/R injury. Thus, FEACR and its downstream factors could be novel targets for alleviating ferroptosis-related myocardial injury in ischemic heart diseases. [ABSTRACT FROM AUTHOR]

Supplemental Digital Content is available in the text. Background: The adult mammalian cardiomyocytes lose their proliferative capacity, which is responsible for cardiac dysfunction and heart failure following injury. The molecular mechanisms underlying the attenuation of adult cardiomyocyte proliferation remain largely unknown. Because long noncoding RNAs (lncRNAs) have a critical role in the development of cardiovascular problems, we investigated whether lncRNAs have any role in the regulation of cardiomyocyte proliferation and cardiac repair. Methods: Using bioinformatics and initial analysis, we identified an lncRNA, named CPR (cardiomyocyte proliferation regulator), that has a potential regulatory role in cardiomyocyte proliferation. For in vivo experiments, we generated CPR knockout and cardiac-specific CPR-overexpressing mice. In isolated cardiomyocytes, we used adenovirus for silencing (CPR–small interfering RNA) or overexpressing CPR. To investigate the mechanisms of CPR function in cardiomyocyte proliferation, we performed various analyses including quantitative reverse transcription–polymerase chain reaction, Western blot, histology, cardiac function (by echocardiography), transcriptome analyses (microarray assay), RNA pull-down assay, and chromatin immunoprecipitation assay. Results: CPR level is comparatively higher in the adult heart than in the fetal stage. The silencing of CPR significantly increased cardiomyocyte proliferation in postnatal and adult hearts. Moreover, CPR deletion restored the heart function after myocardial injury, which was evident from increased cardiomyocyte proliferation, improvement of myocardial function, and reduced scar formation. In contrast, the neonatal cardiomyocyte proliferation and cardiac regeneration were remarkably suppressed in CPR-overexpressing mice or adeno-associated virus serotype 9–CPR—overexpressing heart. These results indicate that CPR acts as a negative regulator of cardiomyocyte proliferation and regeneration. Next, we found that CPR targets minichromosome maintenance 3, an initiator of DNA replication and cell cycle progression, to suppress cardiomyocyte proliferation. CPR silenced minichromosome maintenance 3 expression through directly interacting and recruiting DNMT3A to its promoter cysteine-phosphate-guanine sites, as evident from decreased minichromosome maintenance 3 promoter methylation and increased minichromosome maintenance 3 expression in CPR knocked-down cardiomyocytes and CPR knockout mouse heart. These results were confirmed in CPR-overexpressing cardiomyocytes and CPR-overexpressing mouse heart. Conclusions: Together, our findings identified that CPR is a suppressor of cardiomyocyte proliferation and indicated that lncRNAs take part in the regulation of cardiomyocyte proliferation and cardiac repair. Our study provides an lncRNA-based therapeutic strategy for effective cardiac repair and regeneration. [ABSTRACT FROM AUTHOR]

Golgi-derived PI4P-containing vesicles play important roles in mitochondrial division, which is essential for maintaining cellular homeostasis. However, the mechanism of the PI4P-containing vesicle effect on mitochondrial division is unclear. Here, we found that actin appeared to polymerize at the contact site between PI4P-containing vesicles and mitochondria, causing mitochondrial division. Increasing the content of PI4P derived from the Golgi apparatus increased actin polymerization and reduced the length of the mitochondria, suggesting that actin polymerization through PI4P-containing vesicles is involved in PI4P vesicle-related mitochondrial division. Collectively, our results support a model in which PI4P-containing vesicles derived from the Golgi apparatus cooperate with actin filaments to participate in mitochondrial division by contributing to actin polymerization, which regulates mitochondrial dynamics. This study enriches the understanding of the pathways that regulate mitochondrial division and provides new insight into mitochondrial dynamics. [ABSTRACT FROM AUTHOR]

Purpose To conduct a systematic review and meta-analysis assessing the prevalence of metabolic syndrome (MetS) in patients with systemic lupus erythematosus ( SLE) and the association between SLE and MetS. Method A database search of PubMed, the Cochrane Library, EMBASE, China National Knowledge Infrastructure ( CNKI), Weipu database and Wanfang database updated until March 2017 was conducted. The pooled prevalence, the odds ratio ( OR) and 95% confidence intervals ( CI) were calculated. Publication bias was assessed with Egger's test method. Results In the study of the prevalence of MetS in patients with SLE, 47 studies containing 8367 subjects were included. These studies were published from 2006 to 2016. The pooled prevalence of MetS in patients with SLE was 0.26 (95% CI: 0.23-0.29). In the study of the relationship between SLE and MetS, 24 studies involving 2744 cases and 3028 controls were included. Comparing to control, the SLE patients had high risk of MetS ( OR = 1.88, 95% CI: 1.54-2.30, P = 0.000). Conclusion The systematic review and meta-analysis demonstrated the prevalence of MetS in patients with SLE was 26% and the patients with SLE were more prone to having MetS than the control population. The analysis was a basic summary of all relevant researches and provided valuable evidence for prevention and treatment. [ABSTRACT FROM AUTHOR]

A water-soluble supramolecular polypseudorotaxane was prepared via the host–guest interaction of cucurbit[8]uril and the Ru(bpy)3 complex with bis-naphthalene groups. By employing the intrinsic properties of the Ru(bpy)3 complex, the linear polypseudorotaxane can induce DNA condensation, be used as an inhibitor for DNA cleavage enzymes, and trace the translocation of DNA into 293T cells efficiently. [ABSTRACT FROM AUTHOR]

PIWI‐interacting RNAs (piRNAs) are abundantly expressed in heart. However, their functions and molecular mechanisms during myocardial infarction remain unknown. Here, a heart‐apoptosis‐associated piRNA (HAAPIR), which regulates cardiomyocyte apoptosis by targeting N‐acetyltransferase 10 (NAT10)‐mediated N4‐acetylcytidine (ac4C) acetylation of transcription factor EC (Tfec) mRNA transcript, is identified. HAAPIR deletion attenuates ischemia/reperfusion induced myocardial infarction and ameliorate cardiac function compared to WT mice. Mechanistically, HAAPIR directly interacts with NAT10 and enhances ac4C acetylation of Tfec mRNA transcript, which increases Tfec expression. TFEC can further upregulate the transcription of BCL2‐interacting killer (Bik), a pro‐apoptotic factor, which results in the accumulation of Bik and progression of cardiomyocyte apoptosis. The findings reveal that piRNA‐mediated ac4C acetylation mechanism is involved in the regulation of cardiomyocyte apoptosis. HAAPIR‐NAT10‐TFEC‐BIK signaling axis can be potential target for the reduction of myocardial injury caused by cardiomyocyte apoptosis in ischemia heart diseases. [ABSTRACT FROM AUTHOR]

Objectives: A retrospective cohort study was designed to describe the clinical features and outcomes of pulmonary artery sarcoma (PAS).Methods: Twenty-two (22) consecutive patients diagnosed with PAS by pathological examination were enrolled and followed up until they died or until January 2020. The medical records were retrospectively reviewed to evaluate the clinical characteristics, image findings, and outcomes.Results: 1) Twenty-one (21, 95.5%) patients were firstly misdiagnosed. Dyspnoea was the most common presenting symptom (19 of 22, 86.4%). 2) Filling defects in the right pulmonary artery were seen in 17 patients (77.3%) with computed tomography pulmonary angiography or magnetic resonance pulmonary angiography. Among those patients, 14 underwent positron emission tomography-computed tomography detection and 13 (92.9%) were found to have increased uptake value in the pulmonary artery. 3) The median survival (from diagnosis to death or January 2020) of the total series was 11.6 months (range, 0.7-68.5 months). The estimated cumulative survival rates at 1, 2, and 3 years were 52.6%, 32.8%, and 19.7%, respectively. Patients who received surgery and/or chemo-radiotherapy treatment had a better survival rate compared with patients without treatment (the estimated cumulative survival rates at 1, 2, and 3 years were 60.3%, 39.1%, and 29.3%, respectively, vs 33.3%, 16.6%, and 0, accordingly) and better survival time (median survival 17.02 vs 3.16 months, respectively) (p=0.025).Conclusions: Pulmonary artery sarcoma is easily misdiagnosed, as the symptoms and routine image detection are nonspecific. Positron emission tomography-computed tomography may be helpful in diagnosis. Surgery and/or chemo-radiotherapy offer a chance for better outcomes. [ABSTRACT FROM AUTHOR]

Introduction The relationship between the beneficial effects of pioglitazone in reducing clinical events and plaque inflammatory burden remains unknown. This study aimed to determine whether pioglitazone can reduce the number of plaque thrombosis incidences and whether decreasing plaque inflammation is the mechanism by which pioglitazone reduces plaque thromboses. Methods and Results therosclerotic rabbits were divided into two groups: the atherosclerosis group (n = 13) and pioglitazone group (n = 10). The rabbits underwent pharmacological triggering to induce thrombosis. Serum inflammatory markers, FDG uptake, macrophage, and neovessel staining detected arterial inflammation. PET/ CT scans were performed twice (baseline and posttreatment scans). Plaque area, macrophages, and neovessels were measured and the histologic sections were matched with the PET/ CT scans. Serum MMP-9 and hs CRP were lower in the pioglitazone group compared to the atherosclerosis group. The SUVmean significantly decreased in the pioglitazone group (0.62 ± 0.21 vs. 0.55 ± 0.19, P = 0.008), but increased in the atherosclerosis group (0.61 ± 0.15 vs. 0.91 ± 0.20, P < 0.000). The incidence rate of plaque rupture, plaque area, macrophage density, and neovessel density was significantly lower in rabbits with pioglitazone than without (15% vs. 38%, P < 0.001; 18.00 ± 2.30 vs. 27.00 ± 1.60; P < 0.001; 8.80 ± 3.94 vs. 28.26 ± 2.49; P < 0.001; 16.50 ± 3.09 vs. 29.00 ± 2.11; P < 0.001, respectively). Moreover, plaque area and macrophage density were positively correlated with SUV values. Conclusions Our study suggests that pioglitazone can reduce the number of plaque thrombosis incidences by decreasing plaque inflammation. 18F- FDG- PET/ CT can detect plaque inflammation and assess the effects of antiatherosclerotic drugs. [ABSTRACT FROM AUTHOR]

Background: Various randomized trials have demonstrated that postmastectomy radiotherapy (RT) to the chest wall and comprehensive regional nodal areas improves survival in patients with axillary node-positive breast cancer. Controversy exists as to whether the internal mammary node (IMN) region is an essential component of regional nodal irradiation. Available data on the survival benefit of IMN irradiation (IMNI) are conflicting. The patient populations enrolled in previous studies were heterogeneous and most studies were conducted before modern systemic treatment and three-dimensional (3D) radiotherapy (RT) techniques were introduced. This study aims to assess the efficacy and safety of IMNI in the context of modern systemic treatment and computed tomography (CT)-based RT planning techniques.Methods: POTENTIAL is a prospective, multicenter, open-label, parallel, phase III, randomized controlled trial investigating whether IMNI improves disease-free survival (DFS) in high-risk breast cancer with positive axillary nodes (pN+) after mastectomy. A total of 1800 patients will be randomly assigned in a 1:1 ratio to receive IMNI or not. All patients are required to receive ≥ six cycles of anthracycline and/or taxane-based chemotherapy. Randomization will be stratified by institution, tumor location (medial/central vs. other quadrants), the number of positive axillary nodes (1-3 vs. 4-9 vs. ≥10), and neoadjuvant chemotherapy (yes vs. no). Treatment will be delivered with CT-based 3D RT techniques, including 3D conformal RT, intensity-modulated RT, or volumetric modulated arc therapy. The prescribed dose is 50 Gy in 25 fractions or 43.5 Gy in 15 fractions. Tiered RT quality assurance is required. After RT, patients will be followed up at regular intervals. Oncological and toxilogical outcomes, especially cardiac toxicities, will be assessed.Discussion: This trial design is intended to overcome the limitations of previous prospective studies by recruiting patients with pN+ breast cancer, using DFS as the primary endpoint, and prospectively assessing cardiac toxicities and requiring RT quality assurance. The results of this study will provide high-level evidence for elective IMNI in patients with breast cancer after mastectomy.Trial Registration: ClinicalTrails.gov , NCT04320979 . Registered 25 Match 2020, https://clinicaltrials.gov/ct2/show/NCT04320979. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the dynamic changes in plasma decorin concentration after acute ischemic stroke and to study its relationship with clinical stroke subtypes. We collected three plasma samples from patients with acute ischemic stroke (n = 35) and controls (n = 30): upon admission (1-3 days) between 3 days and 1 week (3-7 days), and between 7 days and 2 weeks (7-14 days). The relationship between Decorin concentration and Trial of ORG10172 in Acute Stroke Treatment (TOAST) subtypes and outcomes were evaluated. The concentration of decorin gradually decreased following the onset of stroke at all different time-points (<3 days, p < 0.05; 3-7 days, p < 0.01; and 7-14 days, p < 0.01) compared to controls. The level of decorin at 7-14 days is significantly lower than that at <3 days ( p < 0.01) in the stroke patients. Decorin levels were lower in the Large-artery atherosclerosis group than the rest of the TOAST subgroups ( p = 0.024). Decorin levels decreased more in the patients with poor outcome (mRS 3-6) than those with favorable outcome (mRS 0-2, p < 0.05) at a time-point of 3-7 days. There is a dynamic reduction in Decorin level the days following ischemic stroke, and the decrement persists at least the first 2 weeks. The dynamic reduction of decorin might indicate that decorin is concomitantly involved in the pathophysiological processes of stroke. Larger studies are needed to confirm whether decorin is a useful marker of stroke and a prognostic indicator of outcome. [ABSTRACT FROM AUTHOR]

Trichlorfon is widely used to control pest insects and various parasitic infestations in agriculture, aquaculture and human medicine. However, the long-term widespread use and overuse of trichlorfon poses risks to public and environmental health. Thus, the aim of this study was to evaluate the interference of trichlorfon on gene transcription patterns in the brain of Rana chensinensis with 4 weeks treatment under control conditions and 0.1 mg/L exposure. In total, 102,013 unigenes were obtained from the brain tissue of R. chensinensis, and 874 differentially expressed genes (DEGs) were identified. Functional annotation indicated that out of 118,643 unigenes, 45,600 (44.7%) were annotated in the Nr, Nt, the Swiss-Prot, KEGG, COG, and GO databases. The differential expression patterns of 4 genes associated with neural activity were selected and validated by quantitative polymerase chain reaction (qPCR). The results revealed that except for the canonical cholinesterase-based mechanism, trichlorfon could act on other receptors and alter certain types of neuronal ion channels as the major target sites. All of these effects ultimately cause disorders of multifunctional pathways and other neurotransmitter pathways in the host. The results further our understanding of the mechanisms underlying nontarget effects of organophosphate insecticides (OPs) through multitargets studies. [ABSTRACT FROM AUTHOR]

Purpose: Although some parameters of positron emission tomography with 18F-fluorodeoxyglucose (18F-FDG) and computed tomography (PET-CT) are somehow helpful in differentiating malignant pleural effusion (MPE) from benign effusions, no individual parameter offers sufficient evidence for its implementation in the clinical practice. The aim of this study was to establish the diagnostic accuracy of a scoring system based on PET-CT (the PET-CT score) in diagnosing MPE. Methods: One prospective derivation cohort of patients with pleural effusions (84 malignant and 115 benign) was used to develop the PET-CT score for the differential diagnosis of malignant pleural effusion. The PET-CT score was then validated in another independent prospective cohort (n = 74). Results: The PET-CT parameters developed for discriminating MPE included unilateral lung nodules and/or masses with increased 18F-FDG uptake (3 points); extrapulmonary malignancies (3 points); pleural thickening with increased 18F-FDG uptake (2 points); multiple nodules or masses (uni- or bilateral lungs) with increased 18F-FDG uptake (1 point); and increased pleural effusion 18F-FDG uptake (1 point). With a cut-off value of 4 points in the derivation cohort, the area under the curve, sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of the PET-CT score to diagnose MPE were 0.949 (95% CI: 0.908–0.975), 83.3% (73.6%–90.6%), 92.2% (85.7%–96.4%), 10.7 (5.6–20.1), and 0.2 (0.1–0.3), respectively. Conclusions: A simple-to-use PET-CT score that uses PET-CT parameters was developed and validated. The PET-CT score can help physicians to differentiate MPE from benign pleural effusions. [ABSTRACT FROM AUTHOR]

Highlights • OP exposure could decline antioxidant enzyme activity in liver of Rana chensinensis. • OP could cause fat accumulation and cytoplasmic vacuolization in hepatic tissue. • OP could destroy rough endoplasmic reticulum and mitochondria of hepatocytes. Abstract This study investigated the effects of low doses of octylphenol (OP) on the oxidative stress and hepatotoxicity in amphibian liver. The frog, Rana chensinensis , were exposed to 10−8, 10−7, 10−6 mol/L OP for 10, 20 and 30 days. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) in liver were reduced at first, then recovered slightly, and the content of malondialdehyde (MDA) and hydrogen peroxide (H 2 O 2) were increased significantly. Histopathology showed that in some liver tissues of OP treated frogs, the hematococoel expansion, the fat accumulation, the cytoplasmic vacuolization and even hepatocyte necrosis were present. Ultrastructure revealed that there were lipid droplet accumulation, mitochondria deformation and nuclear condensation in some hepatocytes. These results confirm that low doses OP exposure can give rise to oxidative stress in the liver of frogs, reduce antioxidant enzymes activities, lead to partial organelles damage in hepatocyte and the fat accumulate in hepatic tissue. [ABSTRACT FROM AUTHOR]

Atomic layer deposition (ALD) is an emerging coating deposition technique filled with potential that is expected to deposit coatings with high laser-induced damage threshold (LIDT). As lasers play an important role in space exploration which are gradually moving to higher orbits and longer lifetimes, a higher demand for space laser coatings has been raising. At the current state of the art, the reliability of ALD-deposited laser coatings for space applications is unclear. This work presents investigations on the stability of three ALD-deposited oxide coatings under space proton and UV radiation at values typical for space environment. Changes in the coatings containing low and high amounts of impurities under space radiation were analyzed through optical parse and composition analysis respectively. Both SiO 2 and Al 2 O 3 coatings with few impurities generated color centers after irradiation, which resulted in increased absorption loss and reduced transmittance and optical band gap, and increased probability of damage under laser irradiation. However, the changes in the ZrO 2 coating were surprising, when the ZrO 2 coating with a large amount of impurities was exposed to radiation, the impurity atoms bound to Zr were displaced first, and the released Zr combined with the oxygen vacancies in the coating, which reduced the number of defects, reduced the absorption loss of the coating, and led to a higher transmittance and an increased optical band-gap. This work provided a novel insight on the impact of the impurities on the stability of the ALD-manufactured oxide coatings against laser-induced damage in effect with space proton and UV radiation. Additionally, we show that high initial LIDT in ALD-prepared oxides may be compromised by the space radiation, while fine tuning of the impurities may result a mitigation approach leading to enhanced laser coatings for space applications. [Display omitted] • The reliability of oxide coatings prepared by ALD under deep space radiation has been investigated systematically. • The damage mechanism of laser coatings under proton and UV radiation was clarified. • The effect of different impurity contents on the damage behavior of the coatings under space radiation was investigated. • This work provides a new approach to the development of space radiation stabilized laser coatings. [ABSTRACT FROM AUTHOR]

Background: The adult mammalian cardiomyocytes lose their proliferative capacity, which is responsible for cardiac dysfunction and heart failure following injury. The molecular mechanisms underlying the attenuation of adult cardiomyocyte proliferation remain largely unknown. Because long noncoding RNAs (lncRNAs) have a critical role in the development of cardiovascular problems, we investigated whether lncRNAs have any role in the regulation of cardiomyocyte proliferation and cardiac repair.Methods: Using bioinformatics and initial analysis, we identified an lncRNA, named CPR (cardiomyocyte proliferation regulator), that has a potential regulatory role in cardiomyocyte proliferation. For in vivo experiments, we generated CPR knockout and cardiac-specific CPR-overexpressing mice. In isolated cardiomyocytes, we used adenovirus for silencing (CPR-small interfering RNA) or overexpressing CPR. To investigate the mechanisms of CPR function in cardiomyocyte proliferation, we performed various analyses including quantitative reverse transcription-polymerase chain reaction, Western blot, histology, cardiac function (by echocardiography), transcriptome analyses (microarray assay), RNA pull-down assay, and chromatin immunoprecipitation assay.Results: CPR level is comparatively higher in the adult heart than in the fetal stage. The silencing of CPR significantly increased cardiomyocyte proliferation in postnatal and adult hearts. Moreover, CPR deletion restored the heart function after myocardial injury, which was evident from increased cardiomyocyte proliferation, improvement of myocardial function, and reduced scar formation. In contrast, the neonatal cardiomyocyte proliferation and cardiac regeneration were remarkably suppressed in CPR-overexpressing mice or adeno-associated virus serotype 9-CPR-overexpressing heart. These results indicate that CPR acts as a negative regulator of cardiomyocyte proliferation and regeneration. Next, we found that CPR targets minichromosome maintenance 3, an initiator of DNA replication and cell cycle progression, to suppress cardiomyocyte proliferation. CPR silenced minichromosome maintenance 3 expression through directly interacting and recruiting DNMT3A to its promoter cysteine-phosphate-guanine sites, as evident from decreased minichromosome maintenance 3 promoter methylation and increased minichromosome maintenance 3 expression in CPR knocked-down cardiomyocytes and CPR knockout mouse heart. These results were confirmed in CPR-overexpressing cardiomyocytes and CPR-overexpressing mouse heart.Conclusions: Together, our findings identified that CPR is a suppressor of cardiomyocyte proliferation and indicated that lncRNAs take part in the regulation of cardiomyocyte proliferation and cardiac repair. Our study provides an lncRNA-based therapeutic strategy for effective cardiac repair and regeneration. [ABSTRACT FROM AUTHOR]

It has been proposed that a decline in sperm quality is associated with exposure to environmental chemicals with estrogenic activity. Seeking possible explanations for this effect, this study investigated the effects of octylphenol (OP) on the synthesis of steroid hormones in amphibian. Rana chensinensis were exposed to 10 −8 , 10 −7 and 10 −6 mol/L OP after 10, 20, 30 and 40 days. The cDNA fragments of StAR (274 bp), CYP17 (303 bp) and CYP19 (322 bp) were cloned. In situ hybridization and immunohistochemistry revealed that positive signals of StAR , CYP17 , CYP19 mRNA and proteins mainly in the Leydig cells of testes. Real-time PCR showed that up-regulation of StAR and CYP19 , and down-regulation of CYP17 after exposure to 10 −8 , 10 −7 and 10 −6 mol/L OP. The results suggest that OP can alter transcriptions of StAR , CYP17 and CYP19 , thus disturb the expressions of StAR, P450c17 and P450arom, thereby adversely affect steroid synthesis. [ABSTRACT FROM AUTHOR]

DNA therapy for cancer requires efficient, selective and safe DNA delivery systems. Compared with other non-viral methods such as lipid or polymer-based DNA delivery vectors, peptide-based DNA delivery systems are biocompatible and biodegradable, which leads to lower immunogenicity and lower toxicity. Moreover, peptide vectors are easier to produce and their compositions easier to control because solid-phase peptide synthesis has been extensively developed. However, peptide-based systems for DNA delivery toward special tumor cells or tissues are still lacking. In this study, we constructed a non-viral 9rR-LTVSPWY peptide-based DNA delivery system and showed that it is able to efficiently and selectively transfect DNA into targeted tumor cells. This work presents a novel strategy for tumor cell-specific DNA delivery and a reference for designing more efficient DNA delivery systems targeted towards various types of cancer. [ABSTRACT FROM AUTHOR]

D-arginine oligomers have been widely used as intracellular delivery vectors both in in vitro and in vivo application. Nevertheless, their internalization pathway is obscure and conflicting results have been obtained concerning their intracellular distribution. In this study, we demonstrate that octa-D-arginine (r8) undergoes diffuse localization throughout the cytoplasm and nucleus even at low concentrations and that r8 (r: D-arginine) enters the cells via direct membrane translocation, unlike R8 (R: L-arginine), of which endocytosis is the major internalization pathway. The observation that R8 and r8 enter the cells through two clearly distinct internalization pathways suggests that the backbone stereochemistry affects the uptake mechanism of oligoarginines. [ABSTRACT FROM AUTHOR]

Abstract: The ability of cell-penetrating peptides (CPPs) to deliver a range of membrane-impermeable molecules into living cells makes them attractive potential vehicles for therapeutics. However, in vivo, the efficiency of CPP delivery to the cytosol remains unsatisfactory owing to endosomal entrapment and/or systemic toxicity, which severely restrict their bioavailability and efficacy in in vivo applications. In this study, we developed a series of novel chimeras consisting of various numbers of d- and l-arginine residues and investigated their cellular uptake behaviors and systemic toxicities. We demonstrated that the intracellular distribution, uptake efficiency, and systemic toxicity of these oligoarginines were all significantly affected by the number of d-arginine residues in the peptide sequence. We also found that a hybrid peptide, (rR)3R2, possessed low systemic toxicity, high uptake efficiency, and, remarkably, achieved efficient cytosolic delivery not only in cultured cells but also in living tissue cells in mice after intravenous injection, implying that this heterogeneous motif might have promising applications in the delivery of cargoes of small sizes directed to cytosolic targets in vivo. Our studies into the uptake mechanism of (rR)3R2 indicate that its cellular uptake was not affected by pharmacological or physical inhibitors of endocytosis but by the elimination of the membrane potential, suggesting that (rR)3R2 does not enter the cells via endocytosis but rather through direct membrane translocation driven by the membrane potential. The results here might provide useful guidelines for the design and application of CPPs in drug delivery. [Copyright &y& Elsevier]

Abstract: The development of non-viral delivery systems that are capable of mediating an efficient, exclusive, and non-invasive transfer of DNA across the blood–brain barrier into the brain is challenging, but essential for the clinical application of gene therapy to brain diseases. Compared with other non-viral DNA carriers (e.g., lipids or polymers), peptide-based DNA delivery systems have many advantages including the ease of synthesis, low immunogenicity, biocompatibility, and biodegradability in vivo. However, all of the existing peptide-based vehicles for DNA delivery lack selectivity toward cells or tissues, which largely limited their applications in vivo. In this study, we demonstrated that an RVG29-9rR peptide-based DNA delivery system was able to transfect Neuro 2a cells in vitro more efficiently and specifically than Lipofectamine LTX & Plus, one of the most efficient commercially available transfection reagents. More significantly, the peptide mediated efficient and brain-targeting reporter gene expression after intravenous injection into mice. Thus, the results herein suggest a new strategy for brain-targeting DNA delivery in vivo. [Copyright &y& Elsevier]

Whilst the installed torpedo anchors in offshore practice are often characterized with off-verticality, the effect of inclination on the anchor pull-out capacity has seemingly received little attention in the research literature. This paper presents a numerical study on the pullout capacities and failure envelopes of inclined embedded torpedo anchors subjected to combined vertical and horizontal loading. Using Coupled Eulerian–Lagrangian finite element method, effects of load inclination, azimuthal angle of pull-out plane and anchor inclination were sequentially evaluated. It was found the most critical pull-out plane is the one that coincides with anchor plane towards the anchor inclination direction. Its corresponding failure envelope, which can be well fitted by a closed form expression, gives the conservative estimation of anchor pull-out capacities. The comprehensive parametric investigation indicated this conservative failure envelope is mainly affected by anchor inclination and soil's strength gradient. A series of tables with fitting constant values appropriate for different strength and inclination conditions were furnished. On these bases, a simple design procedure was developed for estimating the ultimate pull-out capacities of inclined embedded torpedo anchors. The outcomes of this work are likely of help for engineers to factor the anchor inclination into the design practice of torpedo anchors. [ABSTRACT FROM AUTHOR]

Discusses the function of cyclic hexapeptide of a class of unnatural amino acids as a selective receptor for chloride ion. Oligomers of amino acids with significant antimicrobial activities; Preparation of linear hexapeptide of alternating amino acids; Solubility of cyclic hexapeptide in nonpolar organic solvents.