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The development of an efficient screening method for the activity of PET-degrading enzymes represents a significant technological advance in the field of enzyme research, with the potential to facilitate the advancement of enzymes for PET recycling. By examining the stable conditions of PET suspension and enzyme production conditions, we developed a method to quantify PET-degrading enzyme activity in E. coli culture medium using turbidity reduction as an indicator. High PET concentration or ionic strength caused aggregation of PET, and the best condition for activity detection was 0.5 mg mL -1 PET in 50 mM sodium phosphate pH 7.0. Preculture of E. coli increased the purity of enzyme secreted in medium. To evaluate the screening method, 720 colonies of the PET2-7M-H229X-F233X mutant library were analyzed and three candidates of high-activity mutants were obtained. The thermostability of the mutants could also be easily measured by measuring the residual activity after heat treatment. The H229T-F233M mutant showed 3.4 times higher degradation rate against PET film than the template enzyme at the initial time. The molecular dynamics simulation implied that the F233M mutation makes space for making an α helix and that the H229T mutation resolved the steric hindrance with Trp199. These mutations were speculated to change the angle of the Trp199 side chain of PET2 to an angle similar to that of the Trp185 of IsPETase, making it suitable for PET binding to the active center. Screening of activity using PET suspensions is compatible with robotic automation and is expected to be useful for validating computationally predicted mutations., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Background/aim: Recent lung cancer treatments include an immune checkpoint inhibitor (ICI) pembrolizumab, platinum-based agents, plus an additional cytotoxic anticancer agent. Nutritional indices, such as the geriatric nutritional risk index (GNRI) and the prognostic nutritional index (PNI), are known to correlate with the prognosis of cancer chemotherapy. Several previous studies have investigated the relationship between PNI and treatment response in non-small cell lung cancer patients, reporting significantly increased OS and PFS in the high PNI group before treatment. However, the relationship between the three-drug combination and GNRI/PNI is unclear. The current study aimed to investigate the association of nutritional indices with duration of treatment success and occurrence of side effects in triple therapy., Patients and Methods: Seventy-two patients with non-small cell lung cancer, treated with combination of carboplatin, pemetrexed, and pembrolizumab from November 2019 to September 30, 2022, were classified into two groups (High and Low) for GNRI and PNI, and a retrospective study was performed., Results: In terms of time-to-treatment-failure (TTF), univariate and multivariate Cox proportional hazards regression analysis showed the Low-PNI group to have significantly shorter TTF than the High-PNI group (p=0.006); multivariate analysis results also showed PNI as a factor affecting TTF (HR=2.791, 95%CI=1.362-5.721, p=0.005). On the other hand, GNRI was not shown to be a factor affecting TTF., Conclusion: PNI at the start of treatment was an independent prognostic factor affecting treatment success time (TTF) in non-small cell lung cancer patients receiving triple therapy. However, PNI was not shown to be a prognostic predictor of irAE development., (Copyright © 2024, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Background/aim: Osimertinib blood levels and their impact on treatment continuation in patients with EGFR mutation-positive lung cancer is not known. This study investigated the drug blood levels and risk factors affecting treatment continuation., Patients and Methods: Fifty-six patients with recurrent and inoperable epidermal growth factor receptor (EGFR) mutation-positive non-small cell lung cancer who received Osimertinib (80 mg once daily, daily dose) between October 1, 2016, and August 31, 2021, were included. Patients were classified into two groups using a cutoff blood level of 155 ng/ml. The primary endpoint was the relationship between Osimertinib exposure and efficacy, and secondary endpoints were the relationship between Osimertinib exposure and side effects, and the effect of covariates on efficacy and blood levels., Results: The median progression-free survival (PFS) for evaluable patients in the steady-state trough concentration (C min ss ) ≥155 ng/ml and C min ss <155 ng/ml groups was 18.7 months and 31.2 months. Serum albumin (Alb) levels were 3.73±0.40 g/dl and 3.93±0.28 g/dl (p=0.030), respectively, and in multivariate analysis, Alb <3.7 g/dl was associated with a hazard ratio of 5.304 (95%CI=1.431-19.66; p=0.013), indicating that Alb <3.7 g/dl significantly shortened PFS., Conclusion: Free blood concentration of Osimertinib may have been increased by a combination of factors, including decreased hepatic metabolic function and decreased albumin production caused by systemic inflammation in patients with cancer. However, there was no effect of Osimertinib C min ss on PFS., (Copyright © 2023, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

The proband was a male in his seventies who came to our facility because of shortness of breath. He was not anemic but presented dissociation between oxygen saturation (SpO 2 ) and partial pressure of oxygen (PaO 2 ) by blood gas analysis, and also demonstrated hemoglobinopathy after measurement of Hb A 1c using high performance liquid chromatography (HPLC). Twenty-three percent of unknown hemoglobin (Hb) bands were detected. After sequencing the β-globin gene, we noted a missense mutation at codon 74 ( G GC> C GC) (Gly→Arg) of the β-globin chain and he was diagnosed with Hb Aalborg ( HBB : c.223G>C). One of the proband's siblings was diagnosed to have a low SpO 2 level and also diagnosed to carry Hb Aalborg; she was also mildly anemic. This is the first known familial case of Hb Aalborg in Japan. In addition to Hb Aalborg, our case had underlying chronic obstructive pulmonary disease (COPD). Herein we present this case as a rare addition to the hematological literature.

Cytotoxic CD8 + T lymphocytes (CTLs) recognize peptides displayed by HLA class I molecules on cell surfaces, monitoring pathological conditions such as cancer. Difficulty in predicting HLA class I ligands is attributed to the complexity of the Ag processing pathway across the cytosol and the endoplasmic reticulum. By means of HLA ligandome analysis using mass spectrometry, we collected natural HLA class I ligands on a large scale and analyzed the source-protein sequences flanking the ligands. This comprehensive analysis revealed that the frequency of proline at amino acid positions 1-3 upstream of the ligands was selectively decreased. The depleted proline signature was the strongest among all the upstream and downstream profiles. Experiments using live cells demonstrated that the presence of proline at upstream positions 1-3 attenuated CTL responses against a model epitope. Other experiments, in which N-terminal-flanking Ag precursors were confined in the endoplasmic reticulum, demonstrated an inability to remove upstream prolines regardless of their positions, suggesting a need for synergistic action across cellular compartments for making the proline signature. Our results highlight, to our knowledge, a unique role and position of proline for inhibiting downstream epitope presentation, which provides a rule for defining natural peptide-HLA class I repertoire formation and CTL responses., (Copyright © 2019 by The American Association of Immunologists, Inc.)

Angiofibroma of soft tissue (AFST) is an extremely rare soft tissue neoplasm that typically presents as a slow-growing, painless mass in the extremities. The present study reports an unusual case of an intra-articular AFST occurring in the left knee of a 23-year-old female. Physical examination revealed a 3-cm, relatively mobile, elastic-hard, non-tender mass. Magnetic resonance imaging detected an intra-articular soft tissue mass with iso-signal intensity relative to skeletal muscle on T1-weighted sequences and heterogeneous high signal intensity on T2-weighted sequences. Contrast-enhanced fat-suppressed T1-weighted sequences demonstrated strong peripheral enhancement of the mass. An arthroscopic excision of the mass was performed. Histologically, the tumor was composed of spindle- or oval-shaped cells in a fibromyxoid stroma with a prominent vascular pattern. Immunohistochemically, the tumor cells were diffusely positive for vimentin and CD163 and focally positive for CD68, desmin and estrogen receptor. Based on these findings, the tumor was diagnosed as an AFST. The patient had no evidence of local recurrence within 9 months of follow-up. To the best of our knowledge, this is the first case of intra-articular AFST managed successfully with arthroscopic excision.

Mouse PAT1 (putative anion transporter, CEFX, slc26a6), an orthologue of human SLC26A6, was recently identified at the intestinal brush-border membrane and shown to transport organic anions such as formate and oxalate, as well as inorganic ions. In this study, we conducted functional characterization of the uptake of formate by HEK293 cells transfected with PAT1. The uptake of formate by PAT1 was increased in the presence of an outwardly-directed Cl gradient, whereas Na had no effect, and the uptake was independent of pH. The Km of PAT1 for formate was 3.75 mM. Various organic acids exhibited a cis-inhibitory effect on the uptake of formate by PAT1. Furthermore, the uptake was increased by preloading with -lactate, nicotinate, valproate and short-and medium-chain fatty acids, showing a trans-stimulatory effect. Thus, it was suggested that PAT1 transports organic acids as well as inorganic anions, demonstrating that it is involved in the intestinal absorption of anionic organic weak acids in the small intestine.

1. Diflubenzuron and polyoxin D clearly inhibited the incorporation of [3H]-N-acetylglucosamine ([3H]NAGA) into chitin in the isolated integument from newly molted American cockroaches under the experimental condition. 2. Upon homogenization, or tissue slicing, such an inhibitory effect of diflubenzuron on chitin synthesis totally disappeared, while that of polyoxin D did not. 3. Mitochondrial poisons (oligomycin and FCCP), protein phosphorylation modulations (8-Br-cAMP, Na3VO4 and MnCl2), potassium ionophores (valinomycin), and calmodulin inhibitor (trifluoperazine) clearly inhibited [3H]NAGA incorporation. 4. Phospholipase A2 and calcium ion significantly enhanced the [3H]NAGA incorporation.