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1.
Chemistry ; 30(38): e202401402, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38719730

ABSTRACT

Amidations employing mixed (carbonic) anhydrides have long been favoured in peptide synthesis because of their cost-effectiveness and less waste generation. Despite their long history, no study has compared the effects of additives on the activation of mixed anhydrides and carbonic anhydrides. In this study, we investigated the amidation of mixed (carbonic) anhydride in the presence of a base and/or Brønsted acids. The use of NMI⋅HCl significantly improved the conversion of the mixed carbonic anhydride, while expediting nucleophilic attacks on the desired carbonyl group. In contrast, in the case of mixed anhydrides, neither the conversion nor the desired nucleophilic attack improved significantly. We developed a C-terminus-free N-methylated peptide synthesis method using mixed carbonic anhydrides in a micro-flow reactor. Fourteen N-alkylated peptides were synthesized in moderate to high yields (55-99 %) without severe racemization (<1 %). Additionally, a significant enhancement in the amidation between mixed carbonic anhydrides and bis-TMS-protected N-methyl amino acids with the inclusion of NMI⋅HCl was observed for the first time. In addition, we observed unexpected C-terminal epimerization of the C-terminus-free N-methyl peptides.


Subject(s)
Anhydrides , Peptides , Peptides/chemistry , Anhydrides/chemistry , Methylation , Acids/chemistry , Alkylation
2.
J Infect Chemother ; 29(4): 422-426, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36682606

ABSTRACT

OBJECTIVES: We investigated the occurrence of non-respiratory bacterial and fungal secondary infections, causative organisms, impact on clinical outcomes, and association between the secondary pathogens and mortality in hospitalized patients with coronavirus disease 2019 (COVID-19). METHODS: This was a retrospective cohort study that included data from inpatients with COVID-19 from multiple centers participating in the Japan COVID-19 Taskforce (April 2020 to May 2021). We obtained demographic, epidemiological, and microbiological data throughout the course of hospitalization and analyzed the cases of COVID-19 complicated by non-respiratory bacterial infections. RESULTS: Of the 1914 patients included, non-respiratory bacterial infections with COVID-19 were diagnosed in 81 patients (4.2%). Of these, 59 (3.1%) were secondary infections. Bacteremia was the most frequent bacterial infection, occurring in 33 cases (55.9%), followed by urinary tract infections in 16 cases (27.1%). Staphylococcus epidermidis was the most common causative organism of bacteremia. Patients with COVID-19 with non-respiratory secondary bacterial infections had significantly higher mortality, and a multivariate logistic regression analysis demonstrated that those with bacteremia (aOdds Ratio = 15.3 [5.97-39.1]) were at higher risk of death. Multivariate logistic regression analysis showed that age, male sex, use of steroids to treat COVID-19, and intensive care unit admission increased the risk for nosocomial bacteremia. CONCLUSIONS: Secondary bacteremia is an important complication that may lead to poor prognosis in cases with COVID-19. An appropriate medical management strategy must be established, especially for patients with concomitant predisposing factors.


Subject(s)
Bacteremia , Bacterial Infections , COVID-19 , Coinfection , Mycoses , Humans , Male , COVID-19/complications , COVID-19/epidemiology , Retrospective Studies , Coinfection/epidemiology , Bacteremia/drug therapy , Bacteremia/epidemiology , Bacteremia/microbiology , Bacterial Infections/microbiology , Mycoses/microbiology , COVID-19 Testing
3.
BMC Pulm Med ; 23(1): 146, 2023 Apr 26.
Article in English | MEDLINE | ID: mdl-37101265

ABSTRACT

BACKGROUND: Although cases of respiratory bacterial infections associated with coronavirus disease 2019 (COVID-19) have often been reported, their impact on the clinical course remains unclear. Herein, we evaluated and analyzed the complication rates of bacterial infections, causative organisms, patient backgrounds, and clinical outcome in Japanese patients with COVID-19. METHODS: We performed a retrospective cohort study that included inpatients with COVID-19 from multiple centers participating in the Japan COVID-19 Taskforce (April 2020 to May 2021) and obtained demographic, epidemiological, and microbiological results and the clinical course and analyzed the cases of COVID-19 complicated by respiratory bacterial infections. RESULTS: Of the 1,863 patients with COVID-19 included in the analysis, 140 (7.5%) had respiratory bacterial infections. Community-acquired co-infection at COVID-19 diagnosis was uncommon (55/1,863, 3.0%) and was mainly caused by Staphylococcus aureus, Klebsiella pneumoniae and Streptococcus pneumoniae. Hospital-acquired bacterial secondary infections, mostly caused by Staphylococcus aureus, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia, were diagnosed in 86 patients (4.6%). Severity-associated comorbidities were frequently observed in hospital-acquired secondary infection cases, including hypertension, diabetes, and chronic kidney disease. The study results suggest that the neutrophil-lymphocyte ratio (> 5.28) may be useful in diagnosing complications of respiratory bacterial infections. COVID-19 patients with community-acquired or hospital-acquired secondary infections had significantly increased mortality. CONCLUSIONS: Respiratory bacterial co-infections and secondary infections are uncommon in patients with COVID-19 but may worsen outcomes. Assessment of bacterial complications is important in hospitalized patients with COVID-19, and the study findings are meaningful for the appropriate use of antimicrobial agents and management strategies.


Subject(s)
Bacterial Infections , COVID-19 , Coinfection , Community-Acquired Infections , Cross Infection , Respiratory Tract Infections , Staphylococcal Infections , Humans , COVID-19/complications , COVID-19/epidemiology , SARS-CoV-2 , Retrospective Studies , Coinfection/epidemiology , COVID-19 Testing , East Asian People , Bacterial Infections/epidemiology , Bacterial Infections/microbiology , Respiratory Tract Infections/epidemiology , Community-Acquired Infections/epidemiology , Disease Progression
4.
Am J Respir Cell Mol Biol ; 67(4): 446-458, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35728045

ABSTRACT

Fibroblasts play a central role in the lung fibrotic process. Our recent study identified a novel subpopulation of lung fibroblasts expressing meflin (mesenchymal stromal cell- and fibroblast-expressing Linx paralogue), antifibrotic properties of which were confirmed by murine lung fibrosis model. Meflin-expressing fibroblasts were resistant to fibrogenesis induced by TGF-ß (transforming growth factor-ß), but its underlying mechanisms remain unknown. In this study, evaluation of a silica-nanoparticle-induced lung fibrosis model confirmed the antifibrotic effect of meflin via the regulation of TGF-ß signaling. We conducted comparative gene expression profiling in lung fibroblasts, which identified growth differentiation factor 10 (Gdf10) encoding bone morphogenic protein 3b (BMP3b) as the most downregulated gene in meflin-deficient cells under the profibrotic condition with TGF-ß. We hypothesized that BMP3b can be an effector molecule playing an antifibrotic role downstream of meflin. As suggested by single-cell transcriptomic data, restricted expressions of Gdf10 (Bmp3b) in stromal cells including fibroblasts were confirmed. We examined possible antifibrotic properties of BMP3b in lung fibroblasts and demonstrated that Bmp3b-null fibroblasts were more susceptible to TGF-ß-induced fibrogenic changes. Furthermore, Bmp3b-null mice exhibited exaggerated lung fibrosis induced by silica-nanoparticles in vivo. We also demonstrated that treatment with recombinant BMP3B was effective against TGF-ß-induced fibrogenesis in fibroblasts, especially in the suppression of excessive extracellular matrix production. These lines of evidence suggested that BMP3b is a novel humoral effector molecule regulated by meflin which exerts antifibrotic properties in lung fibroblasts. Supplementation of BMP3B could be a novel therapeutic strategy for fibrotic lung diseases.


Subject(s)
Growth Differentiation Factor 10 , Pulmonary Fibrosis , Animals , Fibroblasts/metabolism , Growth Differentiation Factor 10/metabolism , Lung/metabolism , Mice , Mice, Knockout , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/drug therapy , Pulmonary Fibrosis/genetics , Silicon Dioxide/pharmacology , Transforming Growth Factor beta/metabolism , Transforming Growth Factors/metabolism , Transforming Growth Factors/pharmacology
5.
Eur Respir J ; 58(6)2021 12.
Article in English | MEDLINE | ID: mdl-34049947

ABSTRACT

The prognosis of elderly individuals with idiopathic pulmonary fibrosis (IPF) remains poor. Fibroblastic foci, in which aggregates of proliferating fibroblasts and myofibroblasts are involved, are the pathological hallmark lesions in IPF to represent focal areas of active fibrogenesis. Fibroblast heterogeneity in fibrotic lesions hampers the discovery of the pathogenesis of pulmonary fibrosis. Therefore, to determine the pathogenesis of IPF, identification of functional fibroblasts is warranted. The aim of this study was to determine the role of fibroblasts positive for meflin, identified as a potential marker for mesenchymal stromal cells, during the development of pulmonary fibrosis.We characterised meflin-positive cells in a single-cell atlas established by single-cell RNA sequencing (scRNA-seq)-based profiling of 243 472 cells from 32 IPF lungs and 29 normal lung samples. We determined the role of fibroblasts positive for meflin using bleomycin (BLM)-induced pulmonary fibrosis.scRNA-seq combined with in situ RNA hybridisation identified proliferating fibroblasts positive for meflin in fibroblastic foci, not dense fibrosis, of fibrotic lungs in IPF patients. A BLM-induced lung fibrosis model for meflin-deficient mice showed that fibroblasts positive for meflin had anti-fibrotic properties to prevent pulmonary fibrosis. Although transforming growth factor-ß-induced fibrogenesis and cell senescence with the senescence-associated secretory phenotype were exacerbated in fibroblasts via the repression or lack of meflin, these were inhibited in meflin-deficient fibroblasts with meflin reconstitution.These findings provide evidence to show the biological importance of meflin expression on fibroblasts and myofibroblasts in the active fibrotic region of pulmonary fibrosis.


Subject(s)
Idiopathic Pulmonary Fibrosis , Senescence-Associated Secretory Phenotype , Aged , Animals , Bleomycin , Fibroblasts/pathology , Fibrosis , Humans , Idiopathic Pulmonary Fibrosis/pathology , Lung/pathology , Mice
6.
Part Fibre Toxicol ; 18(1): 21, 2021 06 17.
Article in English | MEDLINE | ID: mdl-34134732

ABSTRACT

BACKGROUND: As the application of silica nanomaterials continues to expand, increasing chances of its exposure to the human body and potential harm are anticipated. Although the toxicity of silica nanomaterials is assumed to be affected by their physio-chemical properties, including size and surface functionalization, its molecular mechanisms remain unclear. We hypothesized that analysis of intracellular localization of the particles and subsequent intracellular signaling could reveal a novel determinant of inflammatory response against silica particles with different physico-chemical properties. RESULTS: We employed a murine intratracheal instillation model of amorphous silica nanoparticles (NPs) exposure to compare their in vivo toxicities in the respiratory system. Pristine silica-NPs of 50 nm diameters (50 nm-plain) induced airway-centered lung injury with marked neutrophilic infiltration. By contrast, instillation of pristine silica particles of a larger diameter (3 µm; 3 µm-plain) significantly reduced the severity of lung injury and neutrophilic infiltration, possibly through attenuated induction of neutrophil chemotactic chemokines including MIP2. Ex vivo analysis of alveolar macrophages as well as in vitro assessment using RAW264.7 cells revealed a remarkably lower cellular uptake of 3 µm-plain particles compared with 50 nm-plain, which is assumed to be the underlying mechanism of attenuated immune response. The severity of lung injury and neutrophilic infiltration was also significantly reduced after intratracheal instillation of silica NPs with an amine surface modification (50 nm-NH2) when compared with 50 nm-plain. Despite unchanged efficacy in cellular uptake, treatment with 50 nm-NH2 induced a significantly attenuated immune response in RAW264.7 cells. Assessment of intracellular redox signaling revealed increased reactive oxygen species (ROS) in endosomal compartments of RAW264.7 cells treated with 50 nm-plain when compared with vehicle-treated control. In contrast, augmentation of endosomal ROS signals in cells treated with 50 nm-NH2 was significantly lower. Moreover, selective inhibition of NADPH oxidase 2 (NOX2) was sufficient to inhibit endosomal ROS bursts and induction of chemokine expressions in cells treated with silica NPs, suggesting the central role of endosomal ROS generated by NOX2 in the regulation of the inflammatory response in macrophages that endocytosed silica NPs. CONCLUSIONS: Our murine model suggested that the pulmonary toxicity of silica NPs depended on their physico-chemical properties through distinct mechanisms. Cellular uptake of larger particles by macrophages decreased, while surface amine modification modulated endosomal ROS signaling via NOX2, both of which are assumed to be involved in mitigating immune response in macrophages and resulting lung injury.


Subject(s)
Nanoparticles , Particulate Matter/toxicity , Silicon Dioxide , Animals , Lung , Macrophages , Mice , Nanoparticles/toxicity , Particle Size , Rats , Reactive Oxygen Species , Silicon Dioxide/toxicity
7.
Knee Surg Sports Traumatol Arthrosc ; 29(8): 2640-2647, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34085108

ABSTRACT

PURPOSE: Intra-articular pathologies, such as labral and chondral lesions, are common in patients with frozen shoulder. This study evaluated the correlations between the range of motion and labral and chondral lesions in patients with frozen shoulder and investigated their pathophysiologies. METHODS: In total, 125 individuals (53 men and 72 women) who underwent arthroscopic pan-capsular release between 2014 and 2020 were included in the study. The range of motion was measured using scapular fixation and true glenohumeral motion under general anaesthesia. The American Shoulder and Elbow Surgeons Shoulder score and the Shoulder Rating Scale score of the University of California, Los Angeles were used to compare intra-articular pathologies. RESULTS: More than 80% of patients with frozen shoulder had labral pathologies, and nearly half of them had chondral pathologies. Labral lesions extending to the anterior rim of the glenoid had a greater range of motion and the greatest total American Shoulder and Elbow Surgeons Shoulder score. More severe chondral lesions had a lesser range of motion, but presented the greatest function scores and the lowest strength scores according to the Shoulder Rating Scale of the University of California, Los Angeles. The pain scores of the American Shoulder and Elbow Surgeons Shoulder score and the Shoulder Rating Scale of the University of California, Los Angeles were not correlated with the degree of these pathologies. The traction force affected the labrum during true range of motion, and the compression force occurred on the articular cartilage during internal rotation at 90° of forward flexion during diagnostic arthroscopy. CONCLUSION: Labral and chondral lesions are common in patients with frozen shoulder. Adherence to the capsulolabral complex induced a limited range of motion and labral and chondral pathologies. Diagnostic arthroscopy with motion is an important method of reproducing the pathogenesis of intra-articular structures for patients with frozen shoulder. LEVEL OF EVIDENCE: Level III.


Subject(s)
Bursitis , Shoulder Joint , Arthroscopy , Bursitis/surgery , Female , Humans , Joint Capsule/surgery , Male , Range of Motion, Articular , Shoulder Joint/surgery , Treatment Outcome
8.
J Orthop Sci ; 26(4): 595-598, 2021 Jul.
Article in English | MEDLINE | ID: mdl-32830021

ABSTRACT

BACKGROUND: The Shoulder Pain and Disability Index (SPADI) is a simple disease specific questionnaire that is used to evaluate the impact of shoulder disorders. The purpose of this study was to translate the SPADI into Japanese (SPADI-Jp) and evaluate its reliability and validity in Japanese patients with shoulder disorders. METHODS: Cross-cultural adaptation of the SPADI was performed according to international guidelines. A total of 100 patients with shoulder disorders participated in this study. Each participant was asked to finish the SPADI-Jp, Disability of Arm, Shoulder and Hand (DASH), and the Short-Form 36 (SF-36) at the initial visit. Thirty-four patients repeated the SPADI-Jp to assess the test-retest reliability. The test-retest reliability was quantified using the interclass correlation coefficient (ICC), while Cronbach's alpha was calculated to assess the internal consistency. The construct validity was assessed using Spearman's rank correlation coefficients. RESULTS: Internal consistency in the SPADI-Jp was very high (0.969), as measured by the Cronbach's alpha. The ICC of the SPADI-Jp was 0.930. There was a strong, positive correlation between the DASH and the SPADI-Jp (r = 0.837, p < 0.001). The SPADI-Jp was significantly correlated with most of the SF-36 subscales. The correlations of the SPADI-Jp with physical subscales of the SF-36 were stronger than those with the other subscales. CONCLUSIONS: We demonstrated that the SPADI-Jp is a reliable and valid self-assessment tool. Because cross-cultural adaptation, validation, and reliability of the disease-specific questionnaire for shoulder pain and disability have not been evaluated in Japan, the SPADI-Jp can be useful for evaluating such patients in the Japanese population.


Subject(s)
Disability Evaluation , Shoulder Pain , Cross-Sectional Studies , Humans , Japan , Reproducibility of Results , Shoulder Pain/diagnosis , Surveys and Questionnaires
9.
Phys Rev Lett ; 125(16): 165001, 2020 Oct 16.
Article in English | MEDLINE | ID: mdl-33124839

ABSTRACT

The polytropic index of free electrons expanding in a magnetic nozzle of varying strength is experimentally investigated under a nearly zero electric field, allowing all the electrons to escape to the axial boundary and never return to the source. The measurements clearly demonstrate a continuous change in the polytropic index from adiabatic 5/3 for a strong magnetic field to isothermal unity for a weak magnetic field, showing that the polytropic index depends on the magnetic field strength. It is shown that the cross-field diffusion and the resultant plasma loss out of the magnetic nozzle effectively reduce the polytropic index. The azimuthal current induced in the plasma is diamagnetic, does work on the magnetic nozzle, and contributes to the reduction of the electron internal energy during the expansion.

10.
J Shoulder Elbow Surg ; 29(9): 1836-1842, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32414610

ABSTRACT

BACKGROUND: A thickened joint capsule is believed to be one of the most specific manifestations of and the primary restraint against range of motion (ROM) in frozen shoulders. The purpose of this study was to evaluate the relationship among ROMs under general anesthesia before surgery and the effects of each joint capsular release on ROM. METHODS: ROM was measured using a goniometer with scapular fixation. Arthroscopic pan-capsular release was performed with the patient in the beach-chair position in the following order: (1) rotator interval, (2) coracohumeral ligament, (3) superior capsule, (4) middle glenohumeral ligament, (5) anterior inferior glenohumeral ligament, and (6) posterior inferior glenohumeral ligament. ROMs in forward flexion (FF), lateral elevation (LE), external rotation with the arm at the side (ER1), external rotation at 90° of LE (ER2), internal rotation at 90° of LE (IR2), horizontal flexion, external rotation at 90° of FF (ER3), and internal rotation at 90° of FF (IR3) were evaluated before and after each release. RESULTS: A total of 32 consecutive shoulders were included. After each capsular release, the ROM recovered; the final ROM was significantly greater on the affected side than on the unaffected side. Significant correlations were found between FF and LE, FF and ER1, ER1 and ER2, ER1 and ER3, ER2 and ER3, and IR2 and IR3 on both sides, regardless of surgery. CONCLUSION: Each segment of the joint capsule affected ROM in all directions, supporting the need for whole-joint capsular release; ROM was significantly greater on the affected side than on the unaffected side after surgery.


Subject(s)
Bursitis/surgery , Joint Capsule Release , Range of Motion, Articular/physiology , Shoulder Joint/surgery , Arthroscopy , Bursitis/physiopathology , Humans , Ligaments, Articular/physiopathology , Ligaments, Articular/surgery , Prospective Studies , Rotation , Shoulder Joint/physiopathology
11.
J Shoulder Elbow Surg ; 29(9): 1884-1891, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32279986

ABSTRACT

BACKGROUND: The etiology of frozen shoulder (FS) remains uncertain. Advanced glycation end-products (AGEs) cause the cross-linking and stabilization of collagen and are increased in FS. The purpose of this study was to elucidate the pathogenesis of FS by evaluating the receptor of AGE (RAGE)-dependent pathways. METHODS: Tissue samples of the coracohumeral ligament (CHL) and anterior inferior glenohumeral ligament (IGHL) were collected from 33 patients with FS, with severe stiffness, and 25 with rotator cuff tears (RCTs) as controls. Gene expression levels of RAGE, high-mobility group box 1 (HMGB1), Toll-like receptor 2 (TLR2), TLR4, nuclear factor-kappa B (NF-kB), and cytokines were evaluated using a quantitative real-time polymerase chain reaction. The immunoreactivities of carboxymethyllysine (CML), pentosidine, and RAGE were also evaluated. CML and pentosidine were further evaluated using high-performance liquid chromatography. RESULTS: Gene expression levels of RAGE, HMGB1, TLR2, TLR4, and NF-kB were significantly greater in the CHLs and IGHLs from the FS group than in those from the RCT group. Immunoreactivities of RAGE and CML were stronger in the CHLs and IGHLs from the FS group than in those from the RCT group. Pentosidine was weakly immunostained in the CHLs and IGHLs from the FS group. CML using high-performance liquid chromatography was significantly greater in the CHLs and IGHLs from the FS group than in those from the RCT group. CONCLUSIONS: AGEs and HMGB1 might play important roles in the pathogenesis of FS by binding to RAGE and activating NF-kB signaling pathways. Suppression of these pathways could be a treatment option for FS.


Subject(s)
Bursitis/metabolism , Ligaments, Articular/metabolism , NF-kappa B/metabolism , Receptor for Advanced Glycation End Products/metabolism , Adult , Aged , Case-Control Studies , Female , Gene Expression , HMGB1 Protein/genetics , HMGB1 Protein/metabolism , Humans , Immunohistochemistry , Male , Middle Aged , NF-kappa B/genetics , Real-Time Polymerase Chain Reaction , Receptor for Advanced Glycation End Products/genetics , Retrospective Studies , Signal Transduction , Toll-Like Receptor 2/genetics , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/metabolism
12.
J Sport Rehabil ; 30(1): 9-15, 2020 Jan 24.
Article in English | MEDLINE | ID: mdl-31982003

ABSTRACT

CONTEXT: Range of motion (ROM) in the glenohumeral joint decreases with age in healthy subjects; however, the underlying mechanism remains unclear. The process of aging of the joint capsule, including the coracohumeral ligament (CHL), could affect ROM limitation. OBJECTIVE: This study investigated correlations between elasticity of the CHL, evaluated by means of shear-wave elastography, and age, side dominance, and ROM in healthy individuals. DESIGN: Experimental study. SETTING: Laboratory. SUBJECTS: Eighty-four healthy volunteers (39 men and 45 women, mean age: 42.6 y) were included. MAIN OUTCOME MEASURES: Subjects were divided into 3 age groups: younger (20-39 y), middle (40-59 y), and older (≥60 y) age groups. With participants in the supine position, CHL elasticity in both shoulders was evaluated in both neutral and 30° external rotation, with arms at the sides. ROM, including forward flexion, lateral elevation, external rotation, 90° abduction with external rotation, and hand behind the back were measured with participants in the standing position. RESULTS: The CHL elastic modulus was higher in the older group than in the younger group in the neutral (78.4 kPa [SD: 37.1] and 56.6 kPa [SD: 31.7], respectively) and 30° external rotation positions (135.5 kPa [SD: 63.5] and 71.4 kPa [SD: 32.2], respectively). Negative correlations were found between the CHL elastic modulus and ROM in terms of 30° external rotation and both external rotation (R = -.59, P = .02) and 90° abduction with external rotation (R = -.71, P = .003) in the older group, with correlation coefficients increasing with age. CONCLUSIONS: Significant correlations were identified between CHL elasticity and ROM in both external rotation and 90° abduction with external rotation with increasing age. Decreased CHL elasticity was strongly associated with decreased shoulder ROM in middle-aged and older individuals.

13.
J Am Chem Soc ; 141(22): 8675-8679, 2019 06 05.
Article in English | MEDLINE | ID: mdl-31095363

ABSTRACT

Formation of giant cyclic complexes by the assembly of small, flexible units is demonstrated by connecting 14 artificial tripeptides (1) with 14 Ni(II) ions. Although tripeptide 1 is very flexible because of the presence of three CH2 groups in the main chain, it formed a tetradecanuclear cyclic complex ([114Ni14]28+) with a large cavity (diameter: ca. 2 nm). In this structure, three tripeptides are coordinated to each Ni(II) center by three different coordination sites in 1, forming a mesh-like structure. Crystal structure analysis and theoretical calculations indicate that the conformation of 1 was controlled by the formation of metal coordination bonds and intramolecular hydrogen bonds. Because of the structural flexibility, the cyclic framework formed both circular and ellipsoidal structures in the crystalline state, depending on the packing structure. In addition, by the conditions of the assembly process, the size of the cavities could be tuned either with a small decrement (dodecanuclear complex [112Ni12]24+) or a large decrement (octanuclear complexes [(1-3H+)4Ni8]4+), in which "shrunk" cavities with a 10-fold difference in diameter (<0.2 nm) were formed by tuning the tripeptide conformation through additional metal coordination to the tripeptide framework. Dynamic light scattering and mass spectrometry studies indicated that the giant cyclic complexes were also present in the solution state.


Subject(s)
Coordination Complexes/chemistry , Nickel/chemistry , Oligopeptides/chemistry , Hydrogen Bonding , Ligands , Models, Molecular , Molecular Conformation
14.
Cancer Sci ; 110(6): 1959-1973, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31004547

ABSTRACT

Activation of transforming growth factor ß (TGF-ß) combined with persistent hypoxia often affects the tumor microenvironment. Disruption of cadherin/catenin complexes induced by these stimulations yields aberrant extracellular matrix (ECM) production, characteristics of epithelial-mesenchymal transition (EMT). Hypoxia-inducible factors (HIF), the hallmark of the response to hypoxia, play differential roles during development of diseases. Recent studies show that localization of cadherin/catenin complexes at the cell membrane might be tightly regulated by protein phosphatase activity. We aimed to investigate the role of stabilized HIF-1α expression by protein phosphatase activity on dissociation of the E-cadherin/ß-catenin complex and aberrant ECM expression in lung cancer cells under stimulation by TGF-ß. By using lung cancer cells treated with HIF-1α stabilizers or carrying doxycycline-dependent HIF-1α deletion or point mutants, we investigated the role of stabilized HIF-1α expression on TGF-ß-induced EMT in lung cancer cells. Furthermore, the underlying mechanisms were determined by inhibition of protein phosphatase activity. Persistent stimulation by TGF-ß and hypoxia induced EMT phenotypes in H358 cells in which stabilized HIF-1α expression was inhibited. Stabilized HIF-1α protein expression inhibited the TGF-ß-stimulated appearance of EMT phenotypes across cell types and species, independent of de novo vascular endothelial growth factor A (VEGFA) expression. Inhibition of protein phosphatase 2A activity abrogated the HIF-1α-induced repression of the TGF-ß-stimulated appearance of EMT phenotypes. This is the first study to show a direct role of stabilized HIF-1α expression on inhibition of TGF-ß-induced EMT phenotypes in lung cancer cells, in part, through protein phosphatase activity.


Subject(s)
Epithelial-Mesenchymal Transition/drug effects , Extracellular Matrix/drug effects , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Transforming Growth Factor beta1/pharmacology , Animals , Cell Hypoxia , Cell Line , Cell Line, Transformed , Cell Line, Tumor , Epithelial-Mesenchymal Transition/genetics , Extracellular Matrix/genetics , Extracellular Matrix/metabolism , Gene Expression Regulation/drug effects , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Protein Stability , RNA Interference , Rats
15.
Biol Pharm Bull ; 42(6): 1034-1037, 2019.
Article in English | MEDLINE | ID: mdl-31155579

ABSTRACT

Malignant mesothelioma (MM) is an aggressive cancer with poor prognosis. We focused on the anticancer activity of tocotrienol (T3) and have reported that a new redox-inactive T3 derivative (6-O-carboxypropyl-α-tocotrienol; T3E) exerts stronger inhibitory effects on MM cell growth than that of T3 in vitro. Furthermore, we have revealed some mechanisms of T3E that are involved in anti-MM effects. However, the effect of T3E in vivo remains unclear. In this study, we compared the plasma concentrations of T3E to that of T3 using mice to clarify differences in pharmacokinetics. Blood was sequentially collected after oral administration of T3 or T3E, and plasma concentrations were analyzed by HPLC. The area under the plasma T3 and T3E concentration-time curve from 0 to 24 h (AUC0-24 h) of T3E was two times higher than that of T3. In addition, we evaluated the effect of T3E oral administration on tumor growth using a xenograft model of mice that were transplanted with human MM cells (H2052 cell line). Tumor volume was significantly reduced without body weight loss in mice orally administered 150 mg/kg T3E once per 2 d for 10 d, which suggests that T3E has potential anti-MM effects.


Subject(s)
Antineoplastic Agents/therapeutic use , Lung Neoplasms/drug therapy , Mesothelioma/drug therapy , Tocotrienols/therapeutic use , Animals , Antineoplastic Agents/blood , Antineoplastic Agents/pharmacokinetics , Cell Line, Tumor , Humans , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Male , Mesothelioma/metabolism , Mesothelioma/pathology , Mesothelioma, Malignant , Mice, Inbred BALB C , Mice, Inbred ICR , Mice, Nude , Oxidation-Reduction , Tocotrienols/blood , Tocotrienols/pharmacokinetics , Tumor Burden/drug effects
16.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1863(9): 1057-1067, 2018 09.
Article in English | MEDLINE | ID: mdl-29906613

ABSTRACT

Fatty acid-binding proteins (FABPs) are involved in binding and storing hydrophobic ligands such as long-chain fatty acids, as well as transporting them to the appropriate compartments in the cell. Epidermal fatty acid-binding protein (FABP5) is an intracellular lipid-binding protein that is abundantly expressed in adipocytes and macrophages. Previous studies have revealed that the FABP5 expression level is closely related to malignancy in various types of cancer. However, its precise functions in the metabolisms of cancer cells remain unclear. Here, we revealed that FABP5 knockdown significantly induced downregulation of the genes expression, such as hormone-sensitive lipase (HSL), monoacylglycerol lipase (MAGL), elongation of long-chain fatty acid member 6 (Elovl6), and acyl-CoA synthetase long-chain family member 1 (ACSL1), which are involved in altered lipid metabolism, lipolysis, and de novo FA synthesis in highly aggressive prostate and breast cancer cells. Moreover, we demonstrated that FABP5 induced inflammation and cytokine production through the nuclear factor-kappa B signaling pathway activated by reactive oxygen species and protein kinase C in PC-3 and MDA-MB-231 cells. Thus, FABP5 might regulate lipid quality and/or quantity to promote aggressiveness such as cell growth, invasiveness, survival, and inflammation in prostate and breast cancer cells. In the present study, we have revealed for the first time that high expression of FABP5 plays a critical role in alterations of lipid metabolism, leading to cancer development and metastasis in highly aggressive prostate and breast cancer cells.


Subject(s)
Fatty Acid-Binding Proteins/genetics , Fatty Acids/biosynthesis , Gene Expression Regulation, Neoplastic , Mammary Glands, Human/metabolism , NF-kappa B/genetics , Prostate/metabolism , Acetyltransferases/genetics , Acetyltransferases/metabolism , Cell Line, Tumor , Coenzyme A Ligases/genetics , Coenzyme A Ligases/metabolism , Cytokines/genetics , Cytokines/metabolism , Fatty Acid Elongases , Fatty Acid-Binding Proteins/antagonists & inhibitors , Fatty Acid-Binding Proteins/metabolism , Female , Humans , Lipid Droplets/chemistry , Lipid Droplets/metabolism , Lipolysis , Male , Mammary Glands, Human/pathology , Monoacylglycerol Lipases/genetics , Monoacylglycerol Lipases/metabolism , NF-kappa B/metabolism , Prostate/pathology , Protein Kinase C/genetics , Protein Kinase C/metabolism , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Reactive Oxygen Species/metabolism , Signal Transduction , Sterol Esterase/genetics , Sterol Esterase/metabolism
17.
Phys Rev Lett ; 120(4): 045001, 2018 Jan 26.
Article in English | MEDLINE | ID: mdl-29437412

ABSTRACT

A specially constructed experiment shows the near perfect adiabatic expansion of an ideal electron gas resulting in a polytropic index greater than 1.4, approaching the adiabatic value of 5/3, when removing electric fields from the system, while the polytropic index close to unity is observed when the electrons are trapped by the electric fields. The measurements were made on collisionless electrons in an argon plasma expanding in a magnetic nozzle. The collision lengths of all electron collision processes are greater than the scale length of the expansion, meaning the system cannot be in thermodynamic equilibrium, yet thermodynamic concepts can be used, with caution, in explaining the results. In particular, a Lorentz force, created by inhomogeneities in the radial plasma density, does work on the expanding magnetic field, reducing the internal energy of the electron gas that behaves as an adiabatically expanding ideal gas.

18.
BMC Pulm Med ; 18(1): 2, 2018 Jan 05.
Article in English | MEDLINE | ID: mdl-29304775

ABSTRACT

BACKGROUND: There is only limited information on the impact of thin-section computed tomography (TSCT)-determined usual interstitial pneumonia (UIP) pattern in the decision-making for resection in newly diagnosed lung cancer patients. METHODS: In this retrospective analysis, data were reviewed from 499 newly diagnosed lung cancer patients who received bronchoscopy between 2010 and 2014. The clinical impact of TSCT-determined UIP pattern on the decision-making process for resection in this cohort was evaluated. RESULTS: The prevalence rate of TSCT-determined fibrosis was 14.8% (74/499 cases), 86.5% (64/74 cases) of which also had TSCT-determined emphysema. The fibrosis group comprised 40 patients with possible UIP and 34 patients with the UIP pattern. Among surgical candidates, the number of surgeries performed was lower in the fibrosis group (60.8%) than in the normal and emphysema groups (84.7 and 77.3%, respectively). Although the proportion of possible UIP did not differ between surgical candidates and patients with resected lung cancer, the proportion of UIP pattern in patients with resected lung cancer was decreased by 8.5%, compared to the surgical candidates. Although measurement of diffusing capacity of the lung for carbon monoxide (DLCO) was performed in more than 97% of patients with thoracic surgery, only 58% of patients without thoracic surgery had DLCO measurement. Multivariate analysis showed that the finding of UIP pattern independently affects the decision-making process for thoracic surgery. The adjusted odds ratios for the comparison between the patients without fibrosis and the patients with UIP pattern was 0.266 (95% confidence intervals: 0.087-0.812). CONCLUSIONS: The presence of TSCT-determined UIP pattern might independently affect the decision-making process for proposing thoracic surgery with curative intent.


Subject(s)
Clinical Decision-Making , Lung Diseases, Interstitial/diagnostic imaging , Lung Neoplasms/surgery , Pulmonary Fibrosis/diagnostic imaging , Tomography, X-Ray Computed , Adult , Aged , Aged, 80 and over , Carbon Monoxide , Female , Humans , Lung Diseases, Interstitial/complications , Lung Diseases, Interstitial/physiopathology , Lung Neoplasms/complications , Lung Neoplasms/pathology , Male , Middle Aged , Patient Selection , Pulmonary Diffusing Capacity , Pulmonary Emphysema/complications , Pulmonary Emphysema/diagnostic imaging , Pulmonary Emphysema/physiopathology , Pulmonary Fibrosis/complications , Pulmonary Fibrosis/physiopathology , Retrospective Studies , Tomography, X-Ray Computed/methods
19.
Pharmacology ; 102(1-2): 26-36, 2018.
Article in English | MEDLINE | ID: mdl-29763912

ABSTRACT

BACKGROUND: Wnt signaling plays an essential role in tumor cell growth, including the development of malignant mesothelioma (MM). Epigenetic silencing of negative Wnt regulators leading to constitutive Wnt signaling has been observed in various cancers and warrants further attention. We have reported that a succinate ether derivative of α-tocotrienol (T3E) has potent cytotoxic effects in MM cells. Thus, in this study, we investigated whether the anti-MM effect of T3E could be mediated via the epigenetic alteration of the Wnt antagonist gene, Dickkopf-1 (DKK1). METHODS: WST-1 and cell analyzers were employed to analyze the effects of T3E on cell viability and apoptosis of human MM cell lines (H2452, H28). Real-time PCR and Western blot were performed to evaluate the expression at mRNA and protein levels. Methylation status and epigenetic modifications of DKK1's promoter regions after T3E treatment in MM cells were studied using methylation-specific PCR and Chromatin immunoprecipitation. Small interfering RNA-mediated knockdown -(siRNA), and specific inhibitors, were used to validate DKK1 as a target of T3E. RESULTS: T3E markedly impaired MM cell viability, increased the expression of phosphorylated-JNK and DKK1 and suppressed cyclin D, a downstream target gene of Wnt signaling. Knockdown of DKK1 expression by siRNA or a specific JNK inhibitor confirmed the contribution of DKK1 and JNK to T3E-induced cytotoxicity in MM cells. On the other hand, cytoskeleton-associated protein 4 (CKAP4) expression, which promotes cell proliferation as a Wnt-independent DKK1 receptor was inhibited by T3E. Silencing CKAP4 by -siRNA did not appear to directly affect MM cell viability, thereby indicating that expression of both DKK1 and CKAP4 is required. Furthermore, T3E-mediated inhibition of both DNA methyltransferases (DNMT1, 3A, and 3B) and histone deacetylases (HDAC1, 2, 3, and 8) in MM cells leads to increased DKK1 expression, thereby promoting tumor growth inhibition. MM cells treated with Zebularine (a DNMT inhibitor) and sodium butyrate (an HDAC inhibitor) exhibited cytotoxic effects, which may explain the inhibitory action of T3E on MM cells. In addition, an enhanced expression of DKK1 in MM cells following T3E treatment is positively correlated with the methylation status of its promoter; T3E decreased DNA methylation and increased histone acetylation. Moreover, T3E specifically increased histone H3 lysine 4 (H3K4) methylation activity, whereas no effects were observed on histone H3K9 and H3K27. CONCLUSIONS: Targeting the epigenetic induction of DKK1 may lead to effective treatment of MM, and T3E has great potential to induce anti-MM activity.


Subject(s)
Epigenesis, Genetic/drug effects , Gene Expression/drug effects , Intercellular Signaling Peptides and Proteins/biosynthesis , Lung Neoplasms/genetics , Mesothelioma/genetics , Tocotrienols/pharmacology , Apoptosis/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Cyclin D/biosynthesis , DNA (Cytosine-5-)-Methyltransferases/antagonists & inhibitors , DNA Methylation/drug effects , Histone Deacetylase Inhibitors/pharmacology , Humans , JNK Mitogen-Activated Protein Kinases/metabolism , Membrane Proteins/biosynthesis , Mesothelioma, Malignant , RNA, Small Interfering/pharmacology
20.
Tohoku J Exp Med ; 244(1): 15-24, 2018 01.
Article in English | MEDLINE | ID: mdl-29311489

ABSTRACT

Rotator cuff tears (RCTs) are a common shoulder problem in the elderly that can lead to both muscle atrophy and fatty infiltration due to less physical load. Satellite cells, quiescent cells under the basal lamina of skeletal muscle fibers, play a major role in muscle regeneration. However, the myogenic potency of human satellite cells in muscles with fatty infiltration is unclear due to the difficulty in isolating from small samples, and the mechanism of the progression of fatty infiltration has not been elucidated. The purpose of this study was to analyze the population of myogenic and adipogenic cells in disused supraspinatus (SSP) and intact subscapularis (SSC) muscles of the RCTs from the same patients using fluorescence-activated cell sorting. The microstructure of the muscle with fatty infiltration was observed as a whole mount condition under multi-photon microscopy. Myogenic differentiation potential and gene expression were evaluated in satellite cells. The results showed that the SSP muscle with greater fatty infiltration surrounded by collagen fibers compared with the SSC muscle under multi-photon microscopy. A positive correlation was observed between the ratio of muscle volume to fat volume and the ratio of myogenic precursor to adipogenic precursor. Although no difference was observed in the myogenic potential between the two groups in cell culture, satellite cells in the disused SSP muscle showed higher intrinsic myogenic gene expression than those in the intact SSC muscle. Our results indicate that satellite cells from the disused SSP retain sufficient potential of muscle growth despite the fatty infiltration.


Subject(s)
Adipose Tissue/pathology , Muscle Development , Rotator Cuff Injuries/pathology , Rotator Cuff/pathology , Satellite Cells, Skeletal Muscle/pathology , Adipogenesis , Aged , Cell Separation , Female , Flow Cytometry , Gene Expression Profiling , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Muscle Fibers, Skeletal/metabolism , Muscular Atrophy/pathology , Rotator Cuff Injuries/genetics , Satellite Cells, Skeletal Muscle/metabolism
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