Characteristics and prognostic analysis of patients with detected KRAS mutations in resected lung adenocarcinomas by peptide nucleic acid-locked nucleic acid polymerase chain reaction (PNA-LNA PCR) clamp method.

Background: Kirsten rat sarcoma virus (KRAS) gene mutations are a type of driver mutation discovered in the 1980s, but for a long time no molecular targeted drugs were available for them. Recently, sotorasib was developed as a molecular targeted drug for KRAS mutations. It is therefore necessary to identify the characteristics of patients with KRAS mutations. Methods: This was the single-institution retrospective study. Surgically resected tumors from lung adenocarcinoma patients were collected at a single institution from June 2016 to September 2019. Peptide nucleic acid-locked nucleic acid polymerase chain reaction (PNA-LNA PCR) clamp analysis of KRAS G12X mutations was compared with analysis by therascreen KRAS RGQ kit. The association between KRAS mutation status and patient characteristics and prognosis was assessed. Results: Among 499 lung adenocarcinomas, KRAS mutations were evaluated in 197 cases, excluding stage IV lung cancer and tumors with epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) mutations. KRAS G12X mutations were detected in 59 cases (29.9%). The highest frequency by gene mutation subtype was G12V in 23 cases (39.0%), followed by G12C in 16 cases (27.1%), G12D in 12 cases (20.3%), G12S in 4 cases (6.8%) and G12A in 2 cases. For the G12C mutation, the PNA-LNA PCR clamp and therascreen methods were consistent, but for the G12D and G12S mutations, the PNA-LNA PCR clamp method showed higher detection rates. In operable tumors, G12C mutations were more frequent in males, smokers, and patients with high expression of programmed death-ligand 1 (PD-L1), and had no correlation with prognosis. Conclusions: By the PNA-LNA PCR clamp method, G12C mutation of surgical specimens was detected successfully. The PNA-LNA PCR clamp method is expected to be applied to the detection of druggable G12C mutations.

A randomized trial to evaluate the preventive effect of lafutidine on chemotherapy-induced peripheral neuropathy in patients treated with carboplatin and paclitaxel for lung cancer.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) has a significant impact on the therapeutic efficacy of chemotherapy and patients' quality of life. The aim of this study was to assess the preventive effect of lafutidine on CIPN. METHODS: Patients were randomly assigned (1:1) to carboplatin and paclitaxel chemotherapy with lafutidine 10 mg twice daily (lafutidine group) or without lafutidine (control group). Peripheral neuropathy in both groups was assessed with the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 and two patient-based questionnaires, the Patient Neurotoxicity Questionnaire (PNQ) and the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity (FACT/GOG-Ntx). The primary outcome was the incidence of grade 2 or higher peripheral neuropathy in CTCAE version 5.0. The target number of cases was set at approximately 40. RESULTS: In total, 18 patients were screened, and 16 patients were assigned to the lafutidine group (n=9) or control group (n=7) between January 2021 and January 2023. Due to poor recruitment, the target number of cases was not reached. Grade 2 or higher neuralgia was 22.2% in the lafutidine group and 14.3% in the control group. Grade 2 or higher peripheral sensory neuropathy was 100% in the lafutidine group and 71.4% in the control group (P=0.175). Grade 3 or higher peripheral neuropathy was not detected in either group. There was no significant difference in PNQ scores between the two groups. Median FACT/GOG-Ntx scores after the fourth cycle tended to be lower in the lafutidine group than in the control group. There was no statistically significant difference in progression free survival (PFS) between the two groups. There were no adverse events due to lafutidine administration. CONCLUSIONS: Although the preventive effect of lafutidine on CIPN could not be demonstrated statistically, lafutidine FACT/GOG-Ntx scores showed a trend toward decreased neurotoxicity as chemotherapy proceeded. More reliable studies using lafutidine on the prevention of CIPN should be conducted. TRIAL REGISTRATION: Japan Registry of Clinical Trials, identifier: jRCTs021200031.

Effect of Hydrogen Bonding on Thermally Activated Delayed Fluorescence Behaviors Based on a Study of Hydrate Crystals.

Reverse intersystem crossing (RISC) in purely organic molecules has become an attractive research topic since the demonstration of high efficiencies in organic light-emitting diodes using thermally activated delayed fluorescence (TADF). Although the intermolecular interactions have a significant impact on the exciton dynamics, it is generally difficult to identify the quantitative relationship associated with a specific factor. In this work, we used a clathrate crystal with TADF and H2O molecules to evaluate the effect of hydrogen bonding while maintaining molecular conformations and other intermolecular interactions. The hydrogen bonding shifted the charge transfer excited states to lower energies, resulting in superior TADF properties. Although the increase in the RISC rate is considered to enhance the stabilities of TADF molecules, photostability analysis revealed nearly the same degradation speed despite the 3 times faster RISC rate.

A Case of Mediastinal Tuberculous Lymphadenitis in a Chronic Dialysis Patient Diagnosed by Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration (EBUS-TBNA).

A 54-year-old woman on dialysis due to chronic renal failure had a fever lasting 2 weeks and was referred to a hospital. Non-enhanced CT and blood tests showed no remarkable findings. She was hospitalized and received an antibacterial drug. Although she was discharged after the fever subsided, she was hospitalized again due to a fever a few days later. A contrast-enhanced CT revealed mediastinal lymphadenopathy, and she was transferred to our hospital for a bronchoscopy. Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration (EBUS-TBNA) for subcarinal lymph nodes was performed in our hospital. The Polymerase Chain Reaction (PCR) test of the obtained specimen was positive for mycobacterium tuberculosis, and histologically, caseous granulomas were found in the specimen. She was diagnosed with mediastinal tuberculous lymphadenitis, and HREZ (isoniazid, rifampicin, ethambutol, and pyrazinamide) treatment was started. The fever subsided immediately, and she was discharged from our hospital 2 weeks after the initiation of treatment. Thereafter, she received treatment as an outpatient. Since the use of a contrast medium was complicated by dialysis, a non-enhanced CT was performed at first, and it was difficult to make a diagnosis from this. We report this as an informative case that could be diagnosed with EBUS-TBNA, which was easily performed on a patient weakened by prolonged fever and dialysis.

A Diversifiable Synthetic Platform for the Discovery of New Carbasugar SGLT2 Inhibitors Using Azide-Alkyne Click Chemistry.

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are clinically available to control blood glucose levels in diabetic patients via an insulin-independent mechanism. It was found that some carbasugar analogs of known SGLT2 inhibitors exert a high inhibiting ability toward SGLT2 and have a prolonged blood glucose lowering effect. In this study, we designed new candidates of carbasugar SGLT2 inhibitor that can be synthesized using copper-catalyzed azide-alkyne cycloaddition (CuAAC) into an aromatic ring, which is a part of the pharmacophore at the final stage in the synthetic protocol for the easier discovery of superior SGLT2 inhibitors. Based on the results of molecular docking studies, some selected compounds have been synthesized. Evaluation of these compounds using a cell-based assay revealed that the majority of these compounds had SGLT2 inhibitory activity in a dose-dependent manner. The SGLT2 inhibitory activity of 7b and 7c was almost equal to that of SGLT2 inhibitors in current use. Furthermore, molecular dynamics simulations also revealed that 7c is a promising novel SGLT2 inhibitor.

Facile separation of cyclic aliphatic and aromatic vapors using crystalline thiacalixarene assemblies with preorganized channels.

Conventional distillation methods cannot separate compounds with similar boiling points, molecular sizes, and volumes, such as cyclohexane and benzene or methylcyclohexane and toluene, effectively. The corresponding cyclic aliphatic and aromatic hydrocarbons cannot be separated effectively using the same type of sorption material. We report that crystalline thiacalixarene assemblies featuring preorganized channel-like adsorption sites are capable of both separations.

Structure-Activity Relationship Study of N-Hydroxyphtalimide Derivatives for the Detection of Amines during Fmoc-Solid-Phase Peptide Synthesis.

Previously, we developed a method for the detection of unprotected amino groups based on their reversible reaction with N-hydroxyphthalimide (NHPI) to form intensely colored products, which can be useful when conducting solid-phase peptide synthesis. Here, we describe a structure-activity relationship study of NHPI derivatives to identify the derivative best suited for this method using a spectrophotometer toward the estimation of chemical yields. We found that the products resulting from the reaction of the derivative with an unprotected amino group were only intensely colored if the structure of the derivative incorporated an NHPI framework. We also prepared five peptides, including those containing N-methyl and D-amino acid, and Pro residues, using our reversible detection method to detect unprotected amino groups. The mechanism of the detection reaction was also studied by the structural analysis of the NHPI (1) and diisopropylamine complex and concluded to entail salt formation between the N-hydroxy group and amine.

A Wnt/ß-catenin signaling inhibitor, IMU1003, suppresses the emergence of osimertinib-resistant colonies from gefitinib-resistant non-small cell lung cancer cells.

Drug resistance has become a challenge in effective longterm molecular targeted therapy. Longterm non-small cell lung cancer (NSCLC) treatments with the first-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) shorten the effective duration of the third-generation EGFR-TKI, osimertinib, via genetic or epigenetic mechanisms in addition to the gatekeeper mutation T790M. This study reproduced this persistence in vitro using gefitinib-resistant NSCLC PC-9 cells (GR cells) and revealed that pharmacological nuclear localization inhibition of ß-catenin suppressed the osimertinib resistance. Osimertinib effectively reduced GR cell survival but left significantly more resistant colonies than parental PC-9 cells. The nuclear fraction of ß-catenin was enriched in GR cells during acquisition of osimertinib resistance. A chemical nuclear localization inhibitor of ß-catenin, IMU1003, dramatically decreased the emergence of osimertinib-resistant colonies. Forced nuclear localization of ß-catenin reduced IMU1003 efficacy. Thus, suppression of the nuclear ß-catenin function may overcome the transgenerational EGFR-TKI-resistance.

Synthesis and Characterization of Cyclotri- and Tetrasiloxanes with Pyrenyl Groups.

Cyclosiloxanes directly bearing polyaromatic groups on silicon atoms have scarcely been reported. Herein, hexa(1-pyrenyl)cyclotrisiloxane (2) and octa(1-pyrenyl)cyclotetrasiloxane (3) were successfully prepared from di(1-pyrenyl)silanediol (1) in the presence of a weak base such as tetraethylammonium acetate and triethylamine in MeCN. The structure of the cyclosiloxanes bearing multiple pyrenyl groups in the solid and solution states was evaluated by NMR, X-ray crystallography, and density functional theory (DFT) calculations. All pyrenyl groups of 2 were oriented outward, and no π-π stacking of adjacent pyrenyl groups was observed. However, all pairs of adjacent pyrenyl groups at 1- and 3-positions in 3 are oriented in the same direction and were π-π stacked with respect to each other. The UV-vis spectra of 2 and 3 in organic solvents showed a slight broadening of the peaks, as observed for typical pyrene derivatives. Interestingly, the fluorescence spectra of 2 showed small monomer and strong excimer emissions; however, those of 3 showed only a strong excimer emission in all solvents. Partially pyrenylated cyclotri- and tetrasiloxanes (compounds 4 and 5) showed solvent-dependent monomer and excimer spectra as observed for di(1-pyrenyl)silane derivatives, implying that the excimer emissions of 2 and 3 arise from mainly geminal and vicinal pyrenyl groups, respectively.

Skeletal Transformation Triggered by C-F Bond Activation after Photochemical Rearrangement of Fluorinated [7]Helicenes.

Tri- and tetra-fluorinated [7]helicenes are photolabile and undergo a double fluorine atom transfer. Herein, we show that the transferred product further undergoes a skeletal transformation on silica gel. The transformation begins with activation of the allylic C-F bond on the silanol surface. Then, the resulting carbocation readily undergoes a regioselective nucleophilic aromatic substitution with water, depending on the position of the fluorine substituents. Hexafluoro-2-propanol also activated the allylic C-F bond and acted as a nucleophile. These findings support the generation of a highly reactive cationic electrophilic intermediate in the successive transformations involving fluorine atoms.

Effect of the conformer distribution on the properties of amorphous organic semiconductor films for organic light-emitting diodes.

With the remarkable improvement in the electrical and optical properties of organic light-emitting diodes (OLEDs) in recent years, the details of the higher-order structure of vacuum-deposited amorphous organic films and its formation mechanism need to be understood. In particular, to clarify the effect of the higher-order structure on the film properties, it is necessary to analyze the molecular aggregation states in the vacuum-deposited amorphous films. Toward their deep understanding, the higher-order structure and film properties have often been discussed with relation to the surface diffusion and structural relaxation of the molecules immediately after deposition on the film surface. However, the effect of the variety of conformers, which is specific to amorphous organic materials, on the thermal and electrical properties of the films has not been deeply discussed. In this study, we focused on three structural isomers of OLED materials and discuss the effect of the conformer distribution on the molecular aggregation states and thermal and electrical properties of the vacuum-deposited films. From their comparison, we found that the properties of the film composed of a relatively small number of stable conformers are superior to those of the other two films composed of relatively large numbers of stable conformers. This superiority originates from formation of aggregates of the same conformer, which become the starting points for crystallization when the film is heated. Our detailed comparison and discussion focusing on the variety of conformers will lead to a deeper understanding of the molecular aggregation states and physical properties of amorphous organic films.

Selective separation of branched alkane vapor by thiacalixarene supramolecular crystals having shape-recognition properties.

Activated crystals of a supramolecular assembly of bromothiacalix[4]arene propyl ether with preorganized channel-like voids can selectively and effectively adsorb isooctane vapor from a vapor mixture of isooctane and n-heptane.

Synthesis of Terminally Fluorinated [7]Helicenes and Their Application to Photochemical Domino Reactions.

The intramolecular Diels-Alder reactions of helicenes deform their π-conjugated screw-shaped skeletons. In particular, terminally tetrafluorinated [7]helicene (F4 -[7]helicene) undergoes a photoinduced Diels-Alder reaction followed by a photoinduced double fluorine atom transfer. Herein, we thoroughly investigated this photochemical domino process by decreasing the level of fluorine substitution. F3 -[7]Helicenes bearing two fluorine atoms at the dienophile terminal underwent photoinduced Diels-Alder reactions, but the whole domino process became slow. F2 -[7]Helicene, which is difluorinated only at the dienophile terminal, was also photolabile. As a result, two fluorine atoms were sufficient for the photochemical domino reaction to occur. X-ray crystallographic analysis revealed that F2 -[7]helicene was less compressed than F4 -[7]helicene, indicating that terminal polyfluorination enhanced the intramolecular arene-fluoroarene stacking interactions and thus promoted the transformations.

Novel Series of Mononuclear Aluminum Complexes for High-Performance Solution-Processed Organic Light-Emitting Devices.

Light metal complexes, such as lithium (Li), sodium (Na), magnesium (Mg), and aluminum (Al) complexes, are attractive candidates for the fabrication of thermally activated delayed fluorescent (TADF) materials. Nevertheless, mononuclear Al complexes with delayed fluorescence have not been developed so far. In this study, we successfully developed a novel series of highly luminescent Al complexes with two phenylacridine-modified asymmetric acetylacetonate-type ligands. These complexes exhibit high photoluminescence quantum yields (PLQYs) of up to 79 % in the solid state with a short delayed fluorescence lifetime of approximately 4 µs. Solution-processed organic light-emitting devices (OLEDs) using these Al complexes exhibit excellent performance with an external quantum efficiency of 17.5 % at 100 cd m-2 . This is the best performance in light metal-based TADF OLEDs reported so far. The results are expected to guide the advancement of the next-generation solid-state lighting technology.

Control of Molecular Orientation in Organic Semiconductors Using Weak Iodine-Iodine Interactions.

Controlling the molecular orientation of materials is a key issue for improving the performance of organic semiconductor devices. Herein, we demonstrate the structure-property relationships of iodinated and noniodinated molecules based on an asymmetric thienoacene framework. The noniodinated molecule formed an antiparallel slip-stack structure with small orbital overlap between molecules. In contrast, the iodinated molecule formed a head-to-head layered-herringbone structure, and as a result, the transfer integrals became larger and the hole mobility increased significantly compared with the noniodinated material. The iodinated molecule was made into a stable and solution-processable p-type organic semiconductor with a mobility of 2.2 cm2 V-1 s-1, which was 2 orders of magnitude higher than that of the noniodinated molecule. This study reveals that controlling molecular orientations using iodine-iodine interactions is a promising strategy for accelerating the development of organic semiconductor materials.

A case of bone marrow involvement in sarcoidosis with crescentic glomerular lesions.

Renal and bone marrow involvements in sarcoidosis are rare. We experienced the case of a 67-year-old man with systemic sarcoidosis, with bone marrow involvement, hepatic involvement and a unique constellation of renal lesion with cellular crescent formation. Immunosuppressive therapy was helpful for maintaining the stability of his pancytopenia, hepatic function and renal function. To the best of our knowledge, the association between sarcoidosis, bone marrow involvement and crescentic glomerulonephritis has been reported in only few cases in literature.

Alkane Shape- and Size-Recognized Selective Vapor Sorption in "Channel-Like" Crystals Based on Thiacalixarene Assemblies.

Invited for the cover of this issue is the group of Manabu Yamada at Akita University and colleagues from Yamagata University and Vellore Institute of Technology. The image depicts two activated "channel-like" crystals, effectively adsorb branched and cyclic alkanes from linear, branched, and cyclic alkane vapors. Read the full text of the article at 10.1002/chem.202000043.

Alkane Shape- and Size-Recognized Selective Vapor Sorption in "Channel-Like" Crystals Based on Thiacalixarene Assemblies.

Alkanes composed of C-C and C-H show a low electric polarization, and therefore, there is only very weak interaction between alkanes and adsorbents. Thus, it is difficult to separate a specific alkane from a mixture of alkanes by adsorption. Here, two activated "channel-like" crystals generated from brominated thiacalix[4]arene propyl ethers, which adopt 1,3-alternate and partial cone conformations, recognize specific alkane vapors depending on alkane-shape and -size, sorting in three-type alkane guests such as linear, branched, and cyclic alkanes. Two activated crystals, which are prepared by removal of solvent upon heating under reduced pressure, incorporate branched and/or cyclic alkane vapors by a unique "gate-opening" mechanism via a crystal transformation in the process. Linear alkane vapors do not trigger gate opening and are not taken up by the activated crystals. The shape and size molecular-recognition properties of the activated crystals promises considerable usefulness for the separation of linear, branched, and cyclic alkanes.

Columnar Stacking of Partially Fluorinated [4]Helicenes: C-H⋠⋠⋠F Interactions Change the Stacking Orientation.

The partial fluorination of polycyclic aromatic hydrocarbons often produces a layered crystal packing, where fluorinated aromatic surfaces are stacked over nonfluorinated aromatic surfaces. Herein, we report the synthesis and crystal packing of partially fluorinated [4]helicenes with steric congestion resulting from H and F atoms in the fjord region. F6 -[4]Helicene forms head-to-tail columnar stacks consisting of an alternate arrangement of perfluorinated and nonfluorinated naphthalene moieties. With decreasing fluorine content, aromatic stacking switched from arene-fluoroarene (ArH -ArF ) hetero-stacking to ArH -ArH /ArF -ArF homo-stacking with the help of intermolecular C-H⋅⋅⋅F contacts in the fjord region. As a result, head-to-head columnar stacks appear. Therefore, the conventional ArH -ArF stacking motif is not always applicable to Fn -[4]helicenes with twisted π-surfaces.

Room-Temperature Phosphorescence from a Series of 3-Pyridylcarbazole Derivatives.

Exploration of pure metal-free organic molecules that exhibit strong room-temperature phosphorescence (RTP) is an emerging research topic. In this regard, unveiling the design principles for an efficient RTP molecule is an essential, but challenging, task. A small molecule is an ideal platform to precisely understand the fundamental role of each functional component because the parent molecule can be easily derivatized. Here, the RTP behaviors of a series of 3-pyridylcarbazole derivatives are presented. Experimental studies in combination with theoretical calculations reveal the crucial role of the n orbital on the central pyridine ring in the dramatic enhancement of the intersystem crossing between the charge-transfer-excited singlet state and the locally excited triplet states. Single-crystal X-ray crystallographic studies apparently indicate that both the pyridine ring and fluorine atom contribute to the enhancement of the RTP because of the restricted motion owing to weak C-H⋅⋅⋅N and H⋅⋅⋅F hydrogen-bonding interactions. The single crystal of the fluorine-substituted derivative shows an ultra-long phosphorescent lifetime (τP ) of 1.1 s and a phosphorescence quantum yield (ΦP ) of 1.2 %, whereas the bromine-substituted derivative exhibits τP of 0.15 s with a ΦP of 7.9 %. We believe that this work provides a fundamental and universal guideline for the generation of pure organic molecules exhibiting strong RTP.