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Background/Aims Optimal risk stratification based on simplified geriatric assessment to predict treatment-related toxicity and survival needs to be clarified in older patients with diffuse large B-cell lymphoma (DLBCL). Methods This multicenter prospective cohort study enrolled newly diagnosed patients with DLBCL (≥ 65 yr) between September 2015 and April 2018. A simplified geriatric assessment was performed at baseline using Activities of Daily Living (ADL), Instrumental ADL (IADL), and Charlson’s Comorbidity Index (CCI). The primary endpoint was event-free survival (EFS). Results The study included 249 patients, the median age was 74 years (range, 65–88), and 125 (50.2%) were female. In multivariable Cox analysis, ADL, IADL, CCI, and age were independent factors for EFS; an integrated geriatric score was derived and the patients stratified into three geriatric categories: fit (n = 162, 65.1%), intermediate-fit (n = 25, 10.0%), and frail (n = 62, 24.9%). The established geriatric model was significantly associated with EFS (fit vs. intermediate-fit, HR 2.61, p < 0.001; fit vs. frail, HR 4.61, p < 0.001) and outperformed each covariate alone or in combination. In 87 intermediate-fit or frail patients, the relative doxorubicin dose intensity (RDDI) ≥ 62.4% was significantly associated with worse EFS (HR, 2.15, 95% CI 1.30–3.53, p = 0.002). It was related with a higher incidence of grade ≥ 3 symptomatic non-hematologic toxicities (63.2% vs. 27.8%, p < 0.001) and earlier treatment discontinuation (34.5% vs. 8.0%, p < 0.001) in patients with RDDI ≥ 62.4% than in those with RDDI < 62.4%. Conclusions This model integrating simplified geriatric assessment can risk-stratify older patients with DLBCL and identify those who are highly vulnerable to standard dose-intensity chemoimmunotherapy.

Carfilzomib, lenalidomide, and dexamethasone (KRd) combination therapy improves the survival of patients with relapsed and/or refractory multiple myeloma (RRMM). Nonetheless, evidence on the use of KRd in Asian populations remains scarce. Accordingly, this study aimed at investigating this regimen’s efficacy in a large group of patients. This retrospective study included patients with RRMM who were treated with KRd at 21 centers between February 2018 and October 2020. Overall, 364 patients were included (median age: 63 years). The overall response rate was 90% in responseevaluable patients, including 69% who achieved a very good partial response or deeper responses. With a median follow-up duration of 34.8 months, the median progression-free survival (PFS) was 23.4 months and overall survival (OS) was 59.5 months. Among adverse factors affecting PFS, highrisk cytogenetics, extramedullary disease, and doubling of monoclonal protein within 2 to 3 months prior to start of KRd treatment significantly decreased PFS and overall survival (OS) in multivariate analyses. Patients who underwent post-KRd stem cell transplantation (i.e.delayed transplant) showed prolonged PFS and OS. Grade 3 or higher adverse events (AEs) were observed in 56% of the patients, and non-fatal or fatal AE’s that resulted in discontinuation of KRd were reported in 7% and 2% of patients, respectively. Cardiovascular toxicity was comparable to that reported in the ASPIRE study. In summary, KRd was effective in a large real-world cohort of patients with RRMM with long-term follow-up. These findings may further inform treatment choices in the treatment of patients with RRMM.

Abstract This study focused on a novel strategy that combines deep learning and radiomics to predict epidermal growth factor receptor (EGFR) mutations in patients with non-small cell lung cancer (NSCLC) using computed tomography (CT). A total of 1280 patients with NSCLC who underwent contrast-enhanced CT scans and EGFR mutation testing before treatment were selected for the final study. Regions of interest were segmented from the CT images to extract radiomics features and obtain tumor images. These tumor images were input into a convolutional neural network model to extract 512 image features, which were combined with radiographic features and clinical data to predict the EGFR mutation. The generalization performance of the model was evaluated using external institutional data. The internal and external datasets contained 324 and 130 EGFR mutants, respectively. Sex, height, weight, smoking history, and clinical stage were significantly different between the EGFR-mutant patient groups. The EGFR mutations were predicted by combining the radiomics and clinical features, and an external validation dataset yielded an area under the curve (AUC) value of 0.7038. The model utilized 1280 tumor images, radiomics features, and clinical characteristics as input data and exhibited an AUC of approximately 0.81 and 0.78 during the primary cohort and external validation, respectively. These results indicate the feasibility of integrating radiomics analysis with deep learning for predicting EGFR mutations. CT-image-based genetic testing is a simple EGFR mutation prediction method, which can improve the prognosis of NSCLC patients and help establish personalized treatment strategies.

Acute myeloid leukemia (AML) is an aggressive malignancy characterized by rapid growth and uncontrolled proliferation of undifferentiated myeloid cells. Metabolic reprogramming is commonly observed in the bone marrow of AML patients, as leukemia cells require increased ATP supply to support disease progression. In this study, we examined the potential role of mesothelin as a metabolic modulator in myeloid cells in AML. Mesothelin is a well-known marker of solid tumors that promotes cancer cell proliferation and survival. We initially analyzed alterations in mesothelin expression in the myeloblast subpopulations, defined as SSC-Alow/CD45dim, obtained from the bone marrow of AML patients using flow cytometry. Our results showed overexpression of mesothelin in 34.8% of AML patients. Subsequently, metabolic changes in leukemia cells were evaluated by comparing the oxygen consumption rates (OCR) of bone marrow samples derived from adult AML patients. Notably, a higher OCR was observed in the mesothelin-positive compared to the mesothelin-low and non-expressing groups. Treatment with recombinant human mesothelin protein enhanced OCR and increased the mRNA expression of glycolytic enzymes and mitochondrial complex II in KG1α AML cells. Notably, siRNA targeting mesothelin in KG1α cells led to the reduction of glycolysis-related gene expression but had no effect on the mitochondrial complex gene. The collective results demonstrate that mesothelin induces metabolic changes in leukemia cells, facilitating the acquisition of a rapid supply of ATP for proliferation in AML. Therefore, the targeting of mesothelin presents a potentially promising approach to mitigating the progression of AML through the inhibition of glycolysis and mitochondrial respiration in myeloid cells.

Background/Aims Recent changes in the diagnostic criteria for myeloproliferative neoplasms (MPNs) and increasing patient numbers necessitate updating of the data on vascular events in patients with such disorders. Methods In this single-center study, thrombotic and hemorrhagic events were retrospectively analyzed in patients diagnosed with essential thrombocythemia (ET), polycythemia vera (PV) prefibrotic/early primary myelofibrosis (pre-PMF), or PMF, based on the 2016 World Health Organization diagnostic criteria. Results Of a total of 335 consecutive patients (139 ET, 42 pre-PMF, 124 PV, and 30 PMF patients; 192 males and 143 females) of median age 64 years (range, 15 to 91), 112 (33.4%) experienced a total of 126 thrombotic events before diagnosis, at the time of diagnosis, or during follow-up over a median of 4.6 years (range, 0.1 to 26.5). Cerebrovascular thrombosis (18.8%) was the most common initial event, followed by coronary heart disease (10.1%) and splanchnic (1.5%) and peripheral thrombosis (1.5%). Arterial thrombosis was more common than venous thrombosis (31.3% vs. 2.1%, respectively; p = 0.001). Thrombosis was most frequent in PV patients (39.5%), followed by patients with pre-PMF (38.1%), ET (30.9%), and PMF (13.3%). Of the 112 patients who experienced thromboses, 53 (47%) and 39 (33.9%) had thrombotic events before and at the time of MPN diagnosis, respectively. Twenty-seven patients (8.1%) experienced 29 hemorrhagic events, of which gastrointestinal bleeding (n = 20) was the most common. Conclusions Most thrombotic events occurred before or at the time of diagnosis, and the prevalence of arterial thrombosis was markedly higher than that of venous thrombosis in patients with MPN.

Purpose: To evaluate the role of the cardiopulmonary exercise test (CPET) with comorbidity index as a predictor of overall survival (OS) and non-relapse mortality (NRM) in patients with hematological malignancies who undergo allogeneic hematopoietic stem cell transplantation (HSCT). Methods: We retrospectively analyzed consecutive adult patients with hematological malignancies who underwent HLA-matched donor-HSCT at Chungnam National University Hospital (Daejeon, South Korea) between January 2014 and December 2020. Maximal oxygen consumption (VO 2 max) was classified using the recommendations of the Mayo Clinic database. Results: Of 72 patients, 38 (52.8%) had VO 2 max values lower than the 25th percentile (VO 2max ≤ 25 th ) of an age- and sex-matched normal population. Patients with VO 2 max ≤ 25 th had no significant differences both OS and NRM (30 month OS 29.8% vs 41%, P = .328; and 30 month NRM 16% vs 3.3%, P = .222), compared with other patients. VO 2 max ≤ 25 th was assigned a weight of 1 when added to the Hematopoietic Cell Transplantation-specific Comorbidity Index (HCT-CI) to form a composite comorbidity/CPET index (HCT-CI/CPET). Patients with HCT-CI/CPET scores of 0 to 1 demonstrated significantly better OS and NRM than did patients with HCT-CI/CPET scores ≥2 [median OS not reached vs 6 months, P

Autoimmune limbic encephalitis (LE) is a rare, but devastating complication of allogeneic hematopoietic stem cell transplantation (HSCT). There is currently limited evidence describing the risk factors, laboratory features, and underlying mechanisms of this neurologic adverse event. We retrospectively reviewed available clinical, imaging, and laboratory data from adult patients with hematological malignancies who underwent haploidentical HSCT with post-transplant cyclophosphamide (PTCy) at Chungnam National University Hospital from June 2016 to May 2020. Patients who developed LE were compared to those who did not based on clinical assessment, serum inflammatory biomarkers, and reconstitution of various T cell populations. Of 35 patients, 4 developed LE. There were no differences in patient demographics, donor demographics, or treatment conditions between patients that did and did not develop LE. Overall, patients with LE had worse clinical outcomes and overall survival than those without. In addition, they tended to have higher markers of systemic inflammation in the early post-transplant period, including fever, C-reactive protein (CRP), and cytokines. Remarkably, baseline interleukin-6 levels before HSCT were found to be higher in patients who developed LE than those who did not. In addition, analysis of T cell subsets showed impaired expansion of CD25+FOXP3+ regulatory T (Treg) cells in LE compared to non-LE patients despite appropriate reconstitution of the total CD4+ T cell population. Patients that developed LE within the first 30 days of HSCT were likely to have high serum IL-6 among other inflammatory cytokines coupled with suppression of regulatory T cell differentiation. Further work is needed on the mechanisms underlying impaired Treg expansion following HSCT and potential therapies.

Growth differentiation factor 15 (GDF15) has been reported to play an important role in cancer and is secreted and involved in the progression of various cancers, including ovarian cancer, prostate cancer, and thyroid cancer. Nevertheless, the functional mechanism of GDF15 in gastric cancer is still unclear. Immunohistochemical staining was performed to estimate the expression of GDF15 in 178 gastric cancer tissues. The biological role and action mechanism of GDF15 were investigated by examining the effect of GDF15 knockdown in AGS and SNU216 gastric cancer cells. Here, we report that the high expression of GDF15 was associated with invasion depth (p = 0.002), nodal involvement (p = 0.003), stage III/IV (p = 0.01), lymphatic invasion (p = 0.05), and tumor size (p = 0.049), which are related to poor survival in gastric cancer patients. GDF15 knockdown induced G0/G1 cell cycle arrest and remarkably inhibited cell proliferation and reduced cell motility, migration, and invasion compared to the control. GDF15 knockdown inhibited the epithelial–mesenchymal transition by regulating the STAT3 phosphorylation signaling pathways. Taken together, our results indicate that GDF15 expression is associated with aggressive gastric cancer by promoting STAT3 phosphorylation, suggesting that the GDF15-STAT3 signaling axis is a potential therapeutic target against gastric cancer progression.

Inhibitors of sodium-glucose cotransporters type 2 (SGLT2) are proposed as a novel approach for the management of type 2 diabetes mellitus. SGLT2 cotransporters are responsible for reabsorption of 90 % of the glucose filtered by the kidney. The glucuretic effect resulting from SGLT2 inhibition contributes to reduce hyperglycaemia and also assists weight loss and blood pressure reduction. In this study, we presented the case of a 59-year-old male who developed hyperosmolar hyperglycemic state (HHS), possibly caused by a sodium-glucose cotransporter 2 (SGLT2) inhibitor, a novel class of antihyperglycemic agents. This case highlights that HHS can develop in patients with diabetes treated with SGLT2 inhibitors

This paper addresses the performance index (PI) of an incremental granular model (IGM) with information granules of linguistic intervals. For this purpose, IGM is designed by combining a linear regression (LR) and an interval-based granular model (GM). The fundamental scheme of IGM construction comprises two essential phases: (1) development of LR as a basic model and (2) design of a local granular model, which attempts to reduce errors obtained by the LR model. Here, the local interval-based GM is based on an interval-based fuzzy clustering algorithm, which is materialized by information granulations. The PI of IGM is calculated by multiplying the coverage with specificity property, because the output of IGM is not a numerical value but a linguistic interval value. From the concept of coverage and specificity, we can construct information granules; thus, it is justified by the available experimental proof and presented as clearly defined semantics. To validate the PI method, an experiment is conducted on concrete compressive strength for civil engineering applications. The experimental results confirm that the PI of IGM is an effective performance evaluation method.

In this study, we classify four horse gaits (walk, sitting trot, rising trot, canter) of three breeds of horse (Jeju, Warmblood, and Thoroughbred) using a neuro-fuzzy classifier (NFC) of the Takagi-Sugeno-Kang (TSK) type from data information transformed by a wavelet packet (WP). The design of the NFC is accomplished by using a fuzzy c-means (FCM) clustering algorithm that can solve the problem of dimensionality increase due to the flexible scatter partitioning. For this purpose, we use the rider’s hip motion from the sensor information collected by inertial sensors as feature data for the classification of a horse’s gaits. Furthermore, we develop a coaching system under both real horse riding and simulator environments and propose a method for analyzing the rider’s motion. Using the results of the analysis, the rider can be coached in the correct motion corresponding to the classified gait. To construct a motion database, the data collected from 16 inertial sensors attached to a motion capture suit worn by one of the country’s top-level horse riding experts were used. Experiments using the original motion data and the transformed motion data were conducted to evaluate the classification performance using various classifiers. The experimental results revealed that the presented FCM-NFC showed a better accuracy performance (97.5%) than a neural network classifier (NNC), naive Bayesian classifier (NBC), and radial basis function network classifier (RBFNC) for the transformed motion data.

Atomic forces are calculated for first-row monohydrides and carbon monoxide within electronic quantum Monte Carlo (QMC). Accurate and efficient forces are achieved by using an improved method for moving variational parameters in variational QMC. Newton’s method with singular value decomposition (SVD) is combined with steepest-descent (SD) updates along directions rejected by the SVD, after initial SD steps. Dissociation energies in variational and diffusion QMC agree well with the experiment. The atomic forces agree quantitatively with potential-energy surfaces, demonstrating the accuracy of this force procedure. The harmonic vibrational frequencies and anharmonicity constants, derived from the QMC energies and atomic forces, also agree well with the experimental values. [ABSTRACT FROM AUTHOR]

In this study, an intelligent predictor is designed for predicting the direction of dinghy booms and coaching dinghy sailing using the designed predictor with information obtained from multiple sensors attached to the dinghy and the sailor. For this purpose, we designed a Takagi-Sugeno-Kang-based linguistic model with interval prediction based on fuzzy granulation, which can be realized by using a context-based fuzzy c-means clustering. The sensors used in this study are cameras, GPS, and an anemometer. The GPS and cameras were attached to the dinghy, and the anemometer was installed on a separate boat near the dinghy. Features are extracted from obtained data to interpret them discretely without sequential data. The boom direction was predicted by collecting information from the dinghy driven by an expert wearing a marked suit to predict the optimal direction. The constructed database was randomly divided into a training set (60%) and a validation set (40%) for a 10-fold cross-validation. The experimental results revealed that in the prediction of the dinghy boom direction, the proposed predictor showed performance improvements of 25.2% and 17.9% on the training and validation sets, respectively, when compared to the previous predictors. [ABSTRACT FROM AUTHOR]

We describe a case of simultaneous development of two opportunistic diseases presenting as similar-looking mass lesions in the cerebrum. A woman in her late 40s was admitted in May 2022 complaining of a sudden onset of right-side weakness (motor grade IV). Previously, she was diagnosed with myasthenia gravis in February 2021 and underwent a thymectomy (thymoma WHO type B2, lung invasion) in May 2021. She has since been taking azathioprine and prednisolone. The magnetic resonance imaging (MRI) of the brain showed masses on the left thalamus and right occipital lobe. Other masses were observed in the anterior neck and left lower lung field. Mass lesions were removed from the occipital lobe of the brain and anterior neck. They were abscesses and Nocardia Veterana was isolated. She was started on intravenous trimethoprim-sulfamethoxazole and carbapenem based on the result of the antimicrobial susceptibility suggested by the Clinical and Laboratory Standards Institute. After one month of treatment, most lesions of the lung and soft tissue disappeared, and her right-side weakness improved (motor grade near V). However, weakness worsened again after 2.5 months of treatment. On repeated MRI, the existing lesions improved, but new multiple central necrotic lesions with ring enhancement after gadolinium injection were seen. This observation made it unclear whether the antibiotic treatment had failed, or a new disease had developed. Tumor removal was repeated from the frontal lobe of the brain, and Epstein-Barr virus-positive diffuse large B-cell lymphoma was diagnosed. Since then, the patient has been receiving additional chemotherapy against lymphoma along with antibacterial treatment. To the best of our knowledge, this is the first reported case of the co-occurrence of cerebral nocardiosis and lymphoma. In conclusion, brain mass lesions in immunodeficient hosts are a diagnostic challenge and biopsy should be considered in cases of uncertainty. [ABSTRACT FROM AUTHOR]

Purpose There is no regimen that is strongly recommended for more than second-line treatment. We investigated the efficacy and safety of platinum/vinorelbine as more than second-line treatment. Materials and Methods We selected patients with advanced non-small cell lung cancer (NSCLC) who received treatment with platinum/vinorelbine at Chungnam National University Hospital from August 2001 to December 2013. The primary end point was the response rate, and secondary end points were progression-free survival (PFS), overall survival (OS), and toxicity. Results Thirty-five patients were enrolled. Response rate was 22.9% (complete response, 0 patients [0%]; partial response, eight patients [22.9%]; stable disease, 10 patients [28.6%]; progressive disease, 14 patients [40.0%]). A significantly higher response rate was observed for patients who had responded to previous chemotherapy than for those who did not (34.8% [8/23] vs. 0% [0/12], p=0.020). The median PFS was 4 months (range, 1 to 21 months). Patients with adenocarcinoma and non-smokers had a significantly longer PFS than patients with non-adenocarcinoma and smokers (5 months vs. 2 months, p=0.007; 4.5 months vs. 2 months, p=0.046, respectively). The median OS was 10 months (range, 1 to 41 months). Patients with good performance status and non-smokers had a significantly longer OS than patients with poor performance status and smokers (14 months vs. 4 months, p=0.02; 18.5 months vs. 6 months, p=0.049, respectively). The main serious adverse event (grade 3 or 4) was neutropenia (15 events, 13.3%) in a total of 113 cycles. Conclusion Platinum/vinorelbine was effective as more than second-line chemotherapy, and the toxicity was tolerable, in patients with advanced NSCLC. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study is to determine the diagnostic and prognostic role of baseline spinal magnetic resonance imaging (MRI) in patients with multiple myeloma. Materials and Methods: We enrolled patients newly diagnosed with multiple myeloma from 2004-2011 at a single center. Abnormal MRI findings that were not detected in radiographs have been analyzed and categorized as malignant compression fractures or extramedullary plasmacytoma. The bone marrow (BM) infiltration patterns on MRI have been classified into five categories. Results: A total of 113 patients with a median age of 65 years (range, 40 to 89 years) were enrolled in the study. Malignant compression fractures not detected in the bone survey were found in 26 patients (23.0%), including three patients (2.6%) with no related symptoms or signs. Extramedullary plasmacytoma was detected in 22 patients (19.5%), including 15 (13.3%) with epidural extension of the tumor. Of these 22 patients, 11 (50.0%) had no relevant symptoms or signs. The presence of malignant compression fractures did not influence overall survival; whereas non-epidural extramedullary plasmacytoma was associated with poor overall survival in the multivariate analysis (hazard ratio, 3.205; 95% confidence interval [CI], 1.430 to 9.845; p=0.042). During the follow-up for a median of 21 months (range, 1 to 91 months), overall survival with the mixed BM infiltrative pattern (median, 24.0 months; 95% CI, 22.9 to 25.1 months) was shorter than those with other patterns (median 56 months; 95% CI, 48.9 to 63.1 months; p=0.030). Conclusion: These results indicate that spine MRI at the time of diagnosis is useful for detecting skeletal lesions and predicting the prognosis in patients with multiple myeloma. [ABSTRACT FROM AUTHOR]

Background: Patients with subclinical hypothyroidism (SHT) are common in clinical practice. However, the clinical significance of SHT, including prognosis, has not been established. Further clarifying SHT will be critical in devising a management plan and treatment guidelines for SHT patients. Thus, the aim of this study was to investigate the prognostic factors of SHT. Methods: We reviewed the medical records of Korean patients who visited the endocrinology outpatient clinic of Severance Hospital from January 2008 to September 2012. Newly-diagnosed patients with SHT were selected and reviewed retrospectively. We compared two groups: the SHT maintenance group and the spontaneous improvement group. Results: The SHT maintenance group and the spontaneous improvement group had initial thyroid-stimulating hormone (TSH) levels that were significantly different (P=0.035). In subanalysis for subjects with TSH levels between 5 to 10 μIU/mL, the spontaneous improvement group showed significantly lower antithyroid peroxidase antibody (anti-TPO-Ab) titer than the SHT maintenance group (P=0.039). Regarding lipid profiles, only triglyceride level, unlike total cholesterol and low density lipoprotein cholesterol, was related to TSH level, which is correlated with the severity of SHT. Diffuse thyroiditis on ultrasonography only contributed to the severity of SHT, not to the prognosis. High sensitivity C-reactive protein and urine iodine excretion, generally regarded as possible prognostic factors, did not show any significant relation with the prognosis and severity of SHT. Conclusion: Only initial TSH level was a definite prognostic factor of SHT. TPO-Ab titer was also a helpful prognostic factor for SHT in cases with mildly elevated TSH. Other than TSH and TPO-Ab, we were unable to validate biochemical prognostic factors in this retrospective study for Korean SHT patients. [ABSTRACT FROM AUTHOR]

Beyond statin therapy for reducing low density lipoprotein cholesterol (LDL-C), additional therapeutic strategies are required to achieve more optimal reduction in cardiovascular risk among diabetic patients with dyslipidemia. To evaluate the effects and the safety of combined treatment with omega-3 fatty acids and statin in dyslipidemic patients with type 2 diabetes, we conducted a randomized, open-label study in Korea. Patients with persistent hypertriglyceridemia (≥200 mg/dL) while taking statin for at least 6 weeks were eligible. Fifty-one patients were randomized to receive either omega-3 fatty acid 4, 2 g, or no drug for 8 weeks while continuing statin therapy. After 8 weeks of treatment, the mean percentage change of low density lipoprotein (LDL) particle size and triglyceride (TG) level was greater in patients who were prescribed 4 g of omega-3 fatty acid with statin than in patients receiving statin monotherapy (2.8%±3.1% vs. 2.3%±3.6%, P=0.024; -41.0%±24.1% vs. -24.2%±31.9%, P= 0.049). Coadministration of omega-3 fatty acids with statin increased LDL particle size and decreased TG level in dyslipidemic patients with type 2 diabetes. The therapy was well tolerated without significant adverse effects. [ABSTRACT FROM AUTHOR]

Acromegaly is generally caused by a benign growth hormone (GH)-secreting pituitary adenoma. It is characterized by a wide range of complications; cardiovascular, respiratory, bone and joint, and metabolic complications. Among them, impaired glucose tolerance and diabetes mellitus, due to GH-induced insulin resistance, has been reported in approximately 16-46% and 19-56%. They are usually improved following the treatment of acromegaly, surgical or medical therapy. We report a first case of 36-year-old man who was paradoxically diagnosed with GAD antibody positive latent autoimmune diabetes in adults (LADA) after the surgical cure of acromegaly. [ABSTRACT FROM AUTHOR]

This paper presents computational evidence for the occurrence of diradical mechanism of self-initiation in thermal polymerization of methyl methacrylate. Two self-initiation mechanisms of interest were explored with first-principles density functional theory calculations. Singlet and triplet potential energy surfaces were constructed. The formation of two Diels−Alder adducts, cis- and trans-dimethyl 1,2-dimethylcyclobutane-1,2-dicarboxylate and dimethyl 2-methyl-5-methylidene-hexanedioate, on the singlet surface was identified. Transition states were calculated using B3LYP/6-31G* and assessed using MP2/6-31G*. The calculated energy barriers and rate constants with different levels of theory were found to show good agreement to corresponding data obtained from laboratory experiments. The presence of a diradical intermediate on the triplet surface was identified. When MCSCF/6-31G* was used, the spin−orbit coupling constant for the singlet to triplet crossover was calculated to be 2.5 cm−1. The mechanism of monoradical generation via a hydrogen abstraction by both triplet and singlet diradicals from a third monomer was identified to be the most likely mechanism of initiation in spontaneous polymerization of methyl methacrylate. [ABSTRACT FROM AUTHOR]

Mixed ices play a central role in characterizing the origin, evolution, stability and chemistry of planetary ice surfaces. Examples include the polar areas of Mars, the crust of the Jupiter moon Europa, or atmospheres of planets and their satellites, particularly in the outer solar system. Atomistic simulations using accurate representations of the interaction potentials have recently shown to be suitable to quantitatively describe both, the mid- and the far-infrared spectrum of mixed H2O/CO amorphous ices. In this work, molecular dynamics simulations are used to investigate structural and spectroscopic properties of mixed and crystalline ices containing H2O, CO and CO2. Particular findings include: (a) the sensitivity of the water bending mode to the local environment of the water molecules which, together with structural insights from MD simulations, provides a detailed picture for the relationship between spectroscopy and structure; and (b) the sensitivity of the low-frequency spectrum to the structure of the mixed CO2/H2O ice. Specifically, for mixed H2O/CO2ices with low water contents isolated water molecules are found which give rise to a band shifted by only 12 cm−1from the gas-phase value whereas for increasing water concentration (for a 1 : 1 mixture) the band progressively shifts to higher frequency because water clusters can form. More generally it is found that changes in the ice structure due to the presence of CO2are larger compared to changes induced by the presence of CO and that this difference is reflected in the shape of the water bending vibration. Thus, the water bending vibration appears to be a suitable diagnostic for structural and chemical aspects of mixed ices. [ABSTRACT FROM AUTHOR]

In this study, the mechanism of self-initiation in spontaneous thermal polymerization of ethyl and n-butyl acrylate is explored using first-principles calculations. Density functional theory (with B3LYP functional and 6-31G* basis set) was used to study [4 + 2] and [2 + 2] cycloaddition reactions on the singlet and triplet potential energy surfaces. Diels−Alder (DA) dimers of ethyl acrylate [6-ethoxy-2-ethoxycarbonyl-3,4-dihydro-2H-pyran (EDP)] and of n-butyl acrylate [6-butoxy-2-butoxycarbonyl-3,4-dihydro-2H-pyran (BDP)] were found to form on the singlet surface via the concerted pathway proposed by Mayo. The formation of diethyl cyclobutane-1,2-dicarboxylate (DECD) and dibutyl cyclobutane-1,2-dicarboxylate (DBCD) via a nonconcerted pathway was identified on the singlet surface of ethyl and n-butyl acrylate, respectively. The presence of a diradical transition state for the formation of the DECD and DBCD was predicted. Triplet potential energy surfaces for the formation of diradical dimer of ethyl and n-butyl acrylate were computed, and the presence of a triplet diradical intermediate was identified for each of the monomers. A low energy monoradical generation mechanism was identified to be involving hydrogen abstraction by a third acrylate monomer from the triplet diradical species. The molecular structure of the computed monoradical species was found to correlate with chain initiating species of the dominant series of peaks in previously reported electrospray ionization-Fourier transform mass spectra of spontaneously polymerized samples of ethyl and n-butyl acrylate. In view of these observations, it is concluded that this self-initiation mechanism is most likely the initiating mechanism in spontaneous thermal polymerization of alkyl acrylates. [ABSTRACT FROM AUTHOR]

This computational study deals with the mechanism of spontaneous initiation in thermal polymerization of alkyl acrylates (e.g., methyl, ethyl, and n-butyl acrylate). The mechanism is presently still unknown. Density-functional theory (DFT) and Møller−Plesset (MP2) calculations are used to explore the Flory and Mayo mechanisms of self-initiation in methyl acrylate. On the singlet surface, a low-barrier, concerted [4 + 2] Diels−Alder mechanism for the formation of a dihydropyran adduct (DA) and a high-barrier nonconcerted [2 + 2] diradical (•M2s•) mechanism for the formation of dimethyl cyclobutane-1,2-dicarboxylate (DCD) were found using B3LYP/6-31G*. Several levels of theory were used to validate the transition states, and the pathways for the DAand DCDformations on the singlet surface were determined using intrinsic reaction coordinate (IRC) calculations. On the triplet surface, a triplet diradical intermediate (•M2t•) was identified that is structurally similar to •M2s•but lower in energy. The spin−orbit coupling constant for crossover of the diradical from singlet to triplet surface was calculated. Monoradical generation from the two intermediates, DAand •M2t•via hydrogen transfer to or from a third methyl acrylate was studied. It was found that generation of two monoradical species was possible from •M2t•and is proposed as a likely explanation for experimentally observed spontaneous-initiation. [ABSTRACT FROM AUTHOR]

We calculated the variational and diffusion quantum Monte Carlo forces using the Hellmann-Feynman theorem and Pulay's correction for the first-row diatomic and triatomic molecules (CO, NO, CO2 and NO2). It is demonstrated that Pulay's correction is important for accurate calculation of forces on non-hydrogen atoms. [ABSTRACT FROM AUTHOR]

We report on the effects of device processing conditions, and of changing the electrode materials, on the switching and negative differential resistance (NDR) behaviour of metal/organic thin film/metal structures. The organic material was an ambipolar molecule containing both electron transporting (oxadiazole) and hole transporting (carbazole) chemical groups. Switching and NDR effects are observed for device architectures with both electrodes consisting of aluminium; optimized switching behaviour is achieved for structures incorporating gold nanoparticles. If one of the Al electrodes is replaced by a higher work function metal or coated with an electron-blocking layer, switching and NDR are no longer observed. The results are consistent with a model based on the creation and destruction of Al filaments within the thin organic layer. [ABSTRACT FROM AUTHOR]

Background/Aims Daratumumab has shown an encouraging antitumor effect in patients with multiple myeloma (MM), and was known to alter the immune properties by off-targeting immunosuppressive cells. Here, we aimed to evaluate the change in absolute lymphocyte count (ALC) as a surrogate marker for predicting survival outcomes of patients treated with daratumumab. Methods Between 2018 and 2021, the medical records of patients with relapsed/refractory MM (RRMM) treated with daratumumab monotherapy at 10 centers in South Korea were reviewed. We collected the ALC data at pre-infusion (D0), day 2 after the first infusion (D2), and prior to the third cycle of daratumumab therapy (D56). Results Fifty patients who were administered at least two cycles of daratumumab were included. Overall response rate was 54.0% after two cycles of daratumumab treatment. On D2, almost all patients experienced a marked reduction in ALC. However, an increase in ALC on D56 (ALCD56) was observed in patients with non-progressive disease, whereas failure of ALC recovery was noted in those with progressive disease. Patients with ALCD56 > 700/μL (n = 39, 78.0%) had prolonged progression-free survival (PFS) and overall survival (OS) than those with ALCD56 ≤ 700/μL (median PFS: 5.8 months vs. 2.6 months, p = 0.025; median OS: 24.1 months vs. 6.1 months, p = 0.004). In addition, ALCD56 >700/μL was a significant favorable prognostic factor for PFS (hazard ratio [HR], 0.22; p = 0.003) and OS (HR, 0.23; p = 0.012). Conclusions Increase in ALC during daratumumab treatment was significantly associated with prolonged survival outcomes in patients with RRMM. The ALC value can predict clinical outcomes in patients treated with daratumumab.

Purpose To examine the prevalence and risk factors of intraocular pathologies after mature cataract surgery. Methods The medical records of 115 patients (115 eyes) diagnosed with brunescent or white cataracts, who underwent surgery at a single primary center between January 2018 and August 2021 were retrospectively reviewed. Dense cataracts precluded preoperative fundus examination in all eyes; however, patients with fundus examination results within 3 months after cataract surgery were included. Logistic regression analyses were performed to identify factors associated with intraocular pathologies. Results Intraocular pathologies were observed in 37 eyes (32.2%) 11.8 ± 13.9 days postoperatively. The most common abnormalities were drusen (6.1%), myopic degeneration (5.2%) and diabetic retinopathy (4.3%). Intraocular pathology in the fellow eye was associated with posterior segment pathology in mature cataract eyes (odds ratio, 47.72; P < 0.001). Conclusions The prevalence of each intraocular pathology found after mature cataract surgery was unremarkable. This study provides clinically useful evidence for clinicians to explain the risk of posterior segment pathology in patients with mature cataracts.

The ability to detect hypochlorite (HOCl/ClO−) in vivo is of great importance to identify and visualize infection. Here, we report the use of imidazoline-2-thione (R1SR2) probes, which act to both sense ClO− and kill bacteria. The N2C=S moieties can recognize ClO− among various typical reactive oxygen species (ROS) and turn into imidazolium moieties (R1IR2) via desulfurization. This was observed through UV–vis absorption and fluorescence emission spectroscopy, with a high fluorescence emission quantum yield (ՓF = 43–99%) and large Stokes shift (∆v∼115 nm). Furthermore, the DIM probe, which was prepared by treating the DSM probe with ClO−, also displayed antibacterial efficacy toward not only Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) but also methicillin-resistant Staphylococcus aureus (MRSA) and extended-spectrum ß-lactamase–producing Escherichia coli (ESBL-EC), that is, antibiotic-resistant bacteria. These results suggest that the DSM probe has great potential to carry out the dual roles of a fluorogenic probe and killer of bacteria.

In this study, we attempted to synthesize visible light active nano-sized photocatalysts using metal oxides such as zinc oxide, zirconium oxide, tungsten oxide, and strontium titanium oxide with (MoCl5)2 as a dopant by the simple ball-milling method. Fourier-transform infrared spectroscopy data confirmed the presence of M-O-Mo linkage (M = Zn, Zr, W, and SrTi) in all the molybdenum-doped metal oxides (MoMOs), but only MoZnO inhibited the growth of the bloom-forming Microcystis aeruginosa under visible light in a concentration-dependent manner up to 10 mg/L. Further, structural characterization of MoZnO using FESEM and XRD exhibited the formation of typical hexagonal wurtzite nanocrystals of approximately 4 nm. Hydroxyl radical (·OH), reactive oxygen species (ROS), and lipid peroxidation assays revealed ·OH generated by MoZnO under the visible light seemed to cause peroxidation of the lipid membrane of M. aeruginosa, which led to an upsurge of intracellular ROS and consequently introduced the agglomeration of cyanobacteria. These results demonstrated that nano-sized MoZnO photocatalyst can be easily synthesized in a cost-effective ball-mill method and utilized for biological applications such as the reduction of harmful algal blooms. Further, our study implies that a simple ball-milling method can provide an easy, green, and scalable route for the synthesis of visible light active doped metal oxides.

Physico- and bio-chemical processes on the femto- to picosecond time scale are ideally suited to be investigated with all-atom simulations. They include, amongst others, vibrational relaxation, ligand migration in sterically demanding environments (proteins, ices), or vibrational spectra. By comparing with experimental data, the results can be used to obtain an understanding of the mechanisms underlying the observations. Furthermore, most of these processes are sensitive to the intermolecular interactions. Therefore, detailed refinement of such interaction potentials is possible.