Adrenalectomy for the treatment of hypotension in a cat with phaeochromocytoma associated with caudal vena cava syndrome

An 11-year-old spayed female, Persian cat was referred to the Jeonbuk Animal Medical Center for evaluation of a 2-month history of lethargy and anorexia. Physical examination revealed tachycardia and hypotension. Abdominal imaging via sonography and CT identified a right adrenal gland mass causing severe deviation and compression of the caudal vena cava. After stabilising the blood pressure and heart rate through positive inotropes and fluid therapy, right adrenalectomy was performed. Surgery confirmed the adrenal gland mass was severely compressing the caudal vena cava. Histopathological examination revealed that the mass was a pheochromocytoma. After adrenalectomy, blood pressure and heart rate stabilised and remained unaffected 8 months postsurgery. This report describes a rare case of an adrenal pheochromocytoma leading to caudal vena cava compression in a cat presenting with hypotension.

Accuracy of artificial intelligence-assisted growth prediction in skeletal Class I preadolescent patients using serial lateral cephalograms for a 2-year growth interval

OBJECTIVE

To investigate the accuracy of artificial intelligence-assisted growth prediction using a convolutional neural network (CNN) algorithm and longitudinal lateral cephalograms (Lat-cephs).

MATERIALS AND METHODS

A total of 198 Japanese preadolescent children, who had skeletal Class I malocclusion and whose Lat-cephs were available at age 8 years (T0) and 10 years (T1), were allocated into the training, validation, and test phases (n = 161, n = 17, n = 20). Orthodontists and the CNN model identified 28 hard-tissue landmarks (HTL) and 19 soft-tissue landmarks (STL). The mean prediction error values were defined as 'excellent,' 'very good,' 'good,' 'acceptable,' and 'unsatisfactory' (criteria: 0.5 mm, 1.0 mm, 1.5 mm, and 2.0 mm, respectively). The degree of accurate prediction percentage (APP) was defined as 'very high,' 'high,' 'medium,' and 'low' (criteria: 90%, 70%, and 50%, respectively) according to the percentage of subjects that showed the error range within 1.5 mm.

RESULTS

All HTLs showed acceptable-to-excellent mean PE values, while the STLs Pog', Gn', and Me' showed unsatisfactory values, and the rest showed good-to-acceptable values. Regarding the degree of APP, HTLs Ba, ramus posterior, Pm, Pog, B-point, Me, and mandibular first molar root apex exhibited low APPs. The STLs labrale superius, lower embrasure, lower lip, point of lower profile, B', Pog,' Gn' and Me' also exhibited low APPs. The remainder of HTLs and STLs showed medium-to-very high APPs.

CONCLUSION

Despite the possibility of using the CNN model to predict growth, further studies are needed to improve the prediction accuracy in HTLs and STLs of the chin area.

Affinity-Directed Site-Specific Protein Labeling and Its Application to Antibody-Drug Conjugates

Chemically modified proteins have diverse applications; however, conventional chemo-selective methods often yield heterogeneously labeled products. To address this limitation, site-specific protein labeling holds significant potential, driving extensive research in this area. Nevertheless, site-specific modification of native proteins remains challenging owing to the complexity of their functional groups. Therefore, a method for site-selective labeling of intact proteins is aimed to design. In this study, a novel approach to traceless affinity-directed intact protein labeling is established, which leverages small binding proteins and genetic code expansion technology. By applying this method, a site-specific antibody labeling with a drug, which leads to the production of highly effective antibody-drug conjugates specifically targeting breast cancer cell lines is achieved. This approach enables traceless conjugation of intact target proteins, which is a critical advantage in pharmaceutical applications. Furthermore, small helical binding proteins can be easily engineered for various target proteins, thereby expanding their potential applications in diverse fields. This innovative approach represents a significant advancement in site-specific modification of native proteins, including antibodies. It also bears immense potential for facilitating the development of therapeutic agents for various diseases.

Targeted kinase degradation via the KLHDC2 ubiquitin E3 ligase

Chemically induced protein degradation is a powerful strategy for perturbing cellular biochemistry. The predominant mechanism of action for protein degrader drugs involves an induced proximity between the cellular ubiquitin-conjugation machinery and a target. Unlike traditional small molecule enzyme inhibition, targeted protein degradation can clear an undesired protein from cells. We demonstrate here the use of peptide ligands for Kelch-like homology domain-containing protein 2 (KLHDC2), a substrate adapter protein and member of the cullin-2 (CUL2) ubiquitin ligase complex, for targeted protein degradation. Peptide-based bivalent compounds that can induce proximity between KLHDC2 and target proteins cause degradation of the targeted factors. The cellular activity of these compounds depends on KLHDC2 binding. This work demonstrates the utility of KLHDC2 for targeted protein degradation and exemplifies a strategy for the rational design of peptide-based ligands useful for this purpose.

Synthesis and antibacterial activities of baulamycin A inspired derivatives

SbnE is an essential enzyme for staphyloferrin B biosynthesis in Staphylococcus aureus. An earlier study showed that natural product baulamycin A has in vitro inhibitory activity against SbnE and antibacterial potency. A SAR study with analogues of baulamycin A was conducted to identify potent inhibitors of SbnE and/or effective antibiotics against MRSA. The results show that selected analogues, including 11, 18, 21, 24a, 24c, 24m and 24n, exhibit single-digit micromolar inhibitory potencies against SbnE (IC50s = 1.81-8.94 μM) and 11, 24m, 24n possess significant activities against both SbnE (IC50s = 4.12-6.12 μM) and bacteria (MICs = 4-32 μg/mL). Biological investigations revealed that these substances possess potent cell wall disruptive activities and that they inhibit siderophore production in MRSA. Among the selected analogues, 7 has excellent antibiotic activities both gram-positive and -negative bacteria (0.5-4 μg/mL). Moreover, these analogues significantly impede biofilm formation in a concentration-dependent manner. Taken together, the results of the investigation provide valuable insight into the nature of novel baulamycin A analogues that have potential efficacy against MRSA owing to their membrane damaging activity and/or inhibitory efficacy against siderophore production.

Identification of Pyrido[3,4-d]pyrimidine derivatives as RIPK3-Mediated necroptosis inhibitors

Necroptosis executed by RIPK3-mediated phosphorylation of MLKL is a programmed necrotic cell death and implicated with various diseases such as sterile inflammation. We designed and synthesized pyrido[3,4-d]pyrimidine derivatives as novel necroptosis inhibitors capable of suppressing the phosphorylation of MLKL. Our SAR studies reveal that 20 possesses comparable inhibitory activity against RIPK3-mediated pMLKL in HT-29 cells relative to GSK872 (2), a representative selective RIPK3 inhibitor. Based on biochemical kinase assay results, 20 is comparable to GSK872 (2) with regard to activity against RIPK3 and less potent against RIPK1 than GSK872, indicating selectivity of 20 towards RIPK3 over RIPK1 is higher than that of GSK872. In HT-29 cells, 20 inhibits necroptosis via MLKL oligomerization impediment. Moreover, 20 suppresses migration and invasion of AsPC-1 cells by necroptosis induced- CXCL5 secretion downregulation. Significantly, 20 could relieve the TNFα-induced systemic inflammatory response syndrome in vivo. Taken together, this study would provide a useful insight into the design of novel necroptosis inhibitors possessing RIPK3-mediated pMLKL inhibitory activity.

Racial Difference in Outcomes in Breast Cancer Patients with Residual Nodal Disease after Neoadjuvant Chemotherapy

PURPOSE/OBJECTIVE(S)

African Americans (AA) requiring neoadjuvant chemotherapy (NAC) have been associated with worse outcomes. Residual nodal disease (ypN+) after NAC represents a highly unfavorable risk factor. We hypothesized that even within this unfavorable subgroup, that racial differences in outcome would persist.

MATERIALS/METHODS

An IRB-approved retrospective review of breast cancer (BC) patients in a multi-institutional study was performed between 2005-2018 to identify ypN+ patients (excluding metastatic or inflammatory BC). Clinico-pathologic parameters stratified by race were collected and analyzed. For molecular subtype analyses, patients were stratified into triple negative (TN), hormone receptor (HR)+/HER2-, and HR+/HER2+, and HR-/HER2+ subtypes. Overall survival (OS), disease free survival (DFS) and recurrence outcomes were obtained, and univariate and multivariate (MVA) logistic regression models were constructed and analyzed.

RESULTS

Among 404 ypN+ patients, 107 (26%) were AA, and 297 (74%) were non-AA. Median follow-up for the non-AA group was 3.8 years (y) (IQR 2.4-6.3) and 3.5y (IQR 2.0-6.2) for the AA group. Clinical and pathologic patient characteristics (age, molecular subtypes, BRCA status, histology, grade, smoking status, primary surgery type, axillary/reconstruction surgery rates, margin status, stage) were without significant statistical differences between the non-AA and AA group, except the non-AA group had proportionally more cN3 disease (10.5% vs. 5.1%; p = .01). Despite this, AA demonstrated worse OS and DFS outcomes (Table). AA also had significantly worse local (15% vs. 6.7%, p = .02), regional (11.2% vs. 5.1%, p = .05) and distant recurrences (32.7% vs. 22.6%, p = .05) compared to non-AA. On MVA for OS and DFS, HR+ status, clinical stage, and AA race (HR 2.1 (CI 1.3-3.4), p = .004 and HR 1.7 (CI 1.1-2.6), p = .01 respectively) remained significant. Molecular subtype analysis demonstrated that AA with HR+/HER2- but not the TN subtypes demonstrated significantly worse outcomes (Table). Utilization of endocrine therapy was not different between AA and non-AA patients (94% vs. 97%, p = 0.3) to explain this discrepancy. Worse outcomes in HER2 subtype for AA group was suggested but could not be statistically verified due to insufficient sample size. There was no discernible difference in chemotherapy and radiation therapy regimen or compliance between the AA and non-AA groups.

CONCLUSION

AA patients who fail to achieve nodal clearance with NAC had higher local, regional and distant recurrence, and worse survival compared to non-AA, particularly those with non-TN status. These differences could not be readily explained by therapeutic disparity, or compliance. These hypothesis generating findings suggest need to explore biological implications, and alternative therapeutic strategies for this unfavorable subgroup.

Multi-Institutional Phase II Trial Using Dose Escalated Five Fraction Stereotactic Partial Breast Irradiation (S-PBI) with GammaPodTM for Early-Stage Breast Cancer

PURPOSE/OBJECTIVE(S)

We report on our early experience of a multi-institutional phase II study of dose escalated five fraction stereotactic partial breast irradiation (S-PBI) for early-stage breast cancer after partial mastectomy using the GammaPodTM stereotactic radiation system.

MATERIALS/METHODS

Patient eligibility included DCIS or invasive epithelial histologies, AJCC clinical stage 0, I, or II with tumor size < 3 cm, and negative margins. Prior safety of Phase I dose escalation has been reported. Dose was 40 Gy delivered in 5 fractions to the CTV, and minimum dose 30 Gy in 5 fractions to the PTV. CTV margin was 1 cm and PTV margin 3 mm. For PTV cavities larger than 100cc, dose was reduced to 35Gy in 5 fractions to the CTV and 30 Gy in 5 fractions to the PTV. Primary endpoint of the study is to determine the 3-year patient global cosmesis score (4-point scale excellent, good, fair, or poor) and adverse cosmesis using a dose escalated approach with smaller PTV margins than conventional methods. Both patients and physicians completed baseline and subsequent cosmesis outcome questionnaires. Treatment related toxicity was graded using the NCI version 4.0 and RTOG/EORTC late radiation scale.

RESULTS

From 3/2019-10/2021, 74 patients were treated respectively. Of these, 38 were treated to 40Gy and 36 were treated to 35 Gy. Median follow up (f/u) was 24 months (mo), range (r) 3-39mo. Median age was 63 years (r 43-77). Histology included 28 DCIS, and 46 invasive carcinomas. 45/46 invasive tumors were ER+. 60/74 (81%) patients received endocrine therapy, and 7/74 patient received chemotherapy. There were 221 acute grade 1 toxicities, and 28 Grade 2 toxicities. No grade 3 or higher acute toxicities were reported (< 90 days). The most common Grade 2 toxicities were radiation dermatitis (10), breast pain (8), blister (4), skin infection (2), nipple discharge (2), and fatigue (2). In the late period, there were 54 Grade 1 late toxicities, 4 Grade 2 late toxicities, and no Grade 3 or higher late toxicities. Grade 2 toxicities included fibrosis (2), and pain (2). Two patients developed grade 1 asymptomatic nonpalpable fat necrosis both diagnosed at 12 months after radiation treatments. The most common grade 1 late toxicities were breast pain (14), hyperpigmentation (8), fibrosis (10), and fatigue (5). Physicians scored cosmesis excellent or good 70/73 (95.8%), 58/60 (96.7%), 36/36 (100%),17/17(100%) respectively at baseline, 12 months, 24 months, and 36months post SBRT, while patients scored the same periods 62/71 (83.7%), 53/59 (89.8%), 33/36 (91.6%), 17/18 (94.4%). There have been no reports of disease recurrences.

CONCLUSION

Results at 24-month median follow-up, of our dose escalated stereotactic partial breast 5 fraction regimen, has low acute and late toxicity, while maintaining high proportion of excellent/good cosmetic outcomes. Continued analysis of all cohorts is in progress.

CLINICAL TRIALS

gov identifier is NCT03581136.

Assessment of Cardiac Radiation Dose in the Co-60 Prone Based Stereotactic Partial Breast Irradiation (CP-sPBI) Using the Distance from the Heart to the Planning Treatment Volume as a Surrogate Marker

PURPOSE/OBJECTIVE(S)

Irradiation of the breast has shown to provide sharp dose gradients using Co-60 prone based stereotactic partial breast irradiation (CP-sPBI), a contemporary device for stereotactic radiotherapy for breast cancer (BC) for accelerated partial breast irradiation (APBI). In addition, the precise setup of CP-sPBI permits a small planning treatment volume (PTV) margin of 3 mm creating a greater distance from PTV to organs at risk. However, to date the factors that influence dose gradients and subsequent cardiac doses of ionizing radiation using CP-sPBI have not been well-studied. Here we evaluate distance of the heart to the lumpectomy PTV cavity and how this effects cardiac dose.

MATERIALS/METHODS

A retrospective database of 113 consecutive patients treated by CP-sPBI for APBI from March 2019 to February 2023 who were treated with 30 Gy in 5 fractions were queried for analysis. The minimum distance from the heart to the PTV (hP) was measured in either the axial or sagittal view. A group of 28 patient cases were randomly selected to achieve an even distribution of 28 cases with hP < 2.75 cm and hP ≥ 2.75 cm to compare cardiac toxicities based on hP. Descriptive analyses were performed to evaluate various cardiac dosimetric parameters based on laterality of BC and hP, using the student's t test.

RESULTS

The mean (range) hP was 4.58 cm (0.80-12.23) for all cases. The subgroup analyses of 28 patient cases with cardiac parameters showed the heart mean (range) dose of 1.20 Gy (0.01-2.11). The mean and max heart dose to the left-sided BC were similar to those to the right-sided BC (mean dose: 1.20 vs. 1.19 Gy; P = 0.97 and max dose: 10.47 vs. 5.66 Gy; P = 0.06). An inverse correlation between hP and mean heart dose was shown with the correlation coefficient of -0.81. Using a cutoff of 2.75 cm hP, the differences between hP < 2.75 and hP ≥ 2.75 cm for all cardiac dosimetric evaluations were all statistically significant, including mean (1.67 vs. 0.79 Gy; p<0.01) and maximal heart dose (14.48 vs. 4.11 Gy; p<0.01) CONCLUSION: CP-sPBI treatment delivery system was able to achieve acceptable clinically relevant heart dosimetric parameters when delivering 5 fraction APBI with a mean heart dose of 1.20 Gy for all locations of PTV cavity volume in the breast. Due to CP-sPBIs excellent dose fall-off characteristics, APBI using CP-SPBI showed clinically acceptable cardiac dosimetric parameters, particularly for PTVs located > 2.75 cm from the heart.

Risk of Sexual Dysfunction in Men Treated with Pelvic Radiation Therapy for Locally Advanced Rectal Cancer: 20 Years of Experience with 451 Patients

PURPOSE/OBJECTIVE(S)

Radiation therapy (RT) is commonly used in the treatment of locally advanced rectal cancer (LARC), but data on its impact on men's sexual health is limited. Given the rising incidence of rectal cancer in younger men, sexual function is an important quality of life factor. We hypothesized that men with LARC treated with RT would be at increased risk of sexual dysfunction compared to men who did not receive RT.

MATERIALS/METHODS

This is a single institution retrospective analysis of outcomes of men ≤50 years diagnosed with LARC between 1999 and 2019. Primary outcomes of erectile dysfunction (ED), ejaculatory dysfunction (EjD), and testosterone deficiency (TD) were assessed via ICD-9/10 codes, and TD was captured with free testosterone <300 ng/dL. Cumulative incidences were calculated with death as a competing risk and p values were calculated using Gray's test. Subdistribution hazard ratios from competing risk regression models were used.

RESULTS

The combined study sample included 451 men: 347 received RT as part of their multimodality treatment, and 104 did not. Median time to last follow up was 5.6 years (IQR 3.3-8.7). Age at diagnosis, stage, and medical comorbidities for sexual dysfunction were similar between the two groups (p>0.05). Cumulative incidence estimates are shown in Table 1, showing a higher cumulative incidence of ED in the RT group, but no difference in EjD or TD between the 2 groups. On univariable analysis, RT, smoking, dyslipidemia, peripheral artery disease, depression, prostate cancer/hyperplasia, closed or current ileostomy, and undergoing rectal cancer surgery were all independent risk factors for ED (p<0.05). On multivariable analysis, RT maintained statistical significance as an independent risk factor for ED (HR 3.87, 95% CI 1.93-7.75, p<0.001). Within the RT group, IMRT compared to 3D (HR 1.54, 95% CI 1.02-2.32, p = 0.040) and groin RT (HR 2.60, 95% CI 1.21-5.59, p = 0.014) were independent risk factors for ED. Within the RT group, groin RT also approached significance as a risk factor for TD (HR 3.61, 95% CI 0.98-13.3, p = 0.054). No RT dose thresholds to external genitals or penile bulb were identified that increased risks of ED, EjD, or TD.

CONCLUSION

RT for LARC independently increases risk of ED but not EjD or TD. IMRT might increase the risk of ED due to increased scatter dose to the genitals and including the inguinal nodes in the target volumes increases the dose to the genitals/testicles, which could translate into a higher risk for ED and TD. Future research on proton RT and prophylactic sildenafil is needed in men ≤50 to decrease the risk of ED.

Financial Toxicity and Patient Experience Outcomes on a Multi-Institutional Phase I Single Fraction Stereotactic Partial Breast Irradiation Protocol for Early-Stage Breast Cancer

PURPOSE/OBJECTIVE(S)

Given the demonstrated financial toxicity (FT) of radiation treatment on breast cancer patients shown in both conventional and our recent 5 fraction stereotactic APBI (S-PBI) study, we assessed the FT, as well as patient-reported utility, quality-of-life and patient experience measures, on patients treated in our phase I single fraction S-PBI trial.

MATERIALS/METHODS

A phase I single fraction dose escalation trial of S-PBI for early-stage breast cancer was conducted. Women with in-situ or stage I-II (AJCC 6) invasive breast cancer following breast conserving surgery were treated with S-PBI in 1 fraction to a total dose of 22.5, 26.5 or 30 Gy (Clinical trials.gov ID NCT02685332). At one month follow-up, patients were asked to complete our novel "Patient Perspective Cost and Convenience of Care Questionnaire". Patients also completed the EQ-5D-5L, including the visual analogue scale of overall health (VAS), at enrollment, 6, 12-, 24-, 36-, and 48-month follow-up.

RESULTS

Of 29 patients enrolled and treated, questionnaire data was available for all patients. Our trial encompassed a wide range of annual household incomes, education, and employment status. Overall, 44.8% (n = 13/29) of patients reported that radiation treatment presented a financial burden. Interestingly, no demographic information, such as patient race, marital status, education, household income, or employment during treatment predicted perceived FT. Patients reporting FT trended towards younger age (median 64 vs 70.5) and having a cancer related co-pay similar to our 5 fraction S-PBI FT trial; however, due to the small size of this study, this did not reach significance (p = 0.24 and 0.10, respectively). VAS and utility scores were calculated per the EQ-5D-5L and remained unchanged from baseline through 4-year follow-up. Likewise, there was no difference in the utility or VAS between patients who reported FT and those who did not. Interestingly, while patient reported cosmesis was similar for all patients at enrollment, patients who reported FT noted significantly worse cosmesis scores (fair/poor vs good/excellent) at 6 month and 2-year follow-ups (p = 0.01 and 0.04, respectively). Finally, patients were surveyed on treatment related disruption to their daily activities and enjoyment of life. The median values were 0 (scale 0-10, with 0 being no disruption) regardless of perceived FT. Patients were also uniformly satisfied with treatment time with a median score of 10 (scale 0-10, 10 being most satisfied).

CONCLUSION

Here, we show that despite using SPBI in a single fraction, nearly half of the patients treated still reported FT of treatment. Importantly, single fraction S-PBI has no negative impact on patient VAS or utility scores, and all patients were uniformly satisfied with treatment time without significant disruption to their life.

Dosimetric Comparison of Adaptive Radiotherapy Modalities for Stereotactic Partial Breast Irradiation

PURPOSE/OBJECTIVE(S)

An increase in the availability of adaptive radiotherapy (ART) platforms have proven to be effective in the treatment of a variety of sites. In this study, we aim to evaluate the effectiveness of non-adaptive RT and 3 different ART platforms: (1) CBCT-based, (2) CT-based, and (3) MRI-based for stereotactic partial breast irradiation (SPBI).

MATERIALS/METHODS

Data were collected from 32 patients (16 left and 16 right breast) treated at a single institution. 16 patients (8 left and 8 right) treated using the non-ART platform were re-planned onto two different ART platforms, CBCT- and MRI-based. The remaining 16 patients treated using CT-based adaptive platform were not re-planned due to the prone patient treatment position (others systems supine). All cases were planned to 30 Gy in 5 fractions. Plan quality was evaluated based on pre-defined planning goals to the OARS: ipsilateral and contralateral lungs (Dmean, Dmax, V20 Gy, V9 Gy), ipsilateral (V15 Gy, V30 Gy) and contralateral breasts (Dmax), heart (Dmean, Dmax, V3 Gy, V1.5 Gy), skin (Dmax, V36.5 Gy), and rib (Dmax, V30 Gy). Target goals were defined by Dmax, Dmin, gradient index, and paddock conformality index. Re-planned cases were compared within the cohort using a paired t-test and a 2-sided t-test was used comparing to the CT-based platform.

RESULTS

Comparing the left and right breast cohort across all platforms, the CT-based ART system showed a signification dose reduction in Dmean (p<0.001 for all platforms), Dmax (p<0.001 for left breast, p<0.03 for right breast) and V9 Gy (p<0.004 for left breast, p<0.001 for right breast) to the ipsilateral lung, V15 Gy (p<0.004 for left breast cohort) to the ipsilateral breast, and Dmax to the contralateral breast (p<0.001) and ribs (p = 0.01, p<0.001, p = 0.01 for CBCT-ART, MRI-ART, and non-ART for left breast cohort only). On average, the MR-Linac platform showed the least degree of OAR sparing across nearly all dosimetric parameters evaluated when compared to all modalities, especially for contralateral lung Dmean and Dmax (p<0.05 for all dosimetric parameters for all platforms) and contralateral breast Dmax (p<0.003 for all platforms). The CBCT-based platform showed superior dose reduction in contralateral lung mean (p<0.03 for all platforms) and heart Dmean (p = 0.065, p<0.001, p = 0.045 for non-adaptive, MRI-ART, and CT-ART for left breast and p<0.008 for right breast). PTV coverage was comparable across all platforms, averaging at approximately 95%. The CT-based ART platform showed a significantly reduced gradient index relative to the CBCT- and MRI-based platforms (p<0.001).

CONCLUSION

For SPBI treatments, the CT-based ART platforms displayed a higher degree of OAR sparing for many of the dosimetric parameters recorded relative to the other ART and non-ART platforms presented. The MRI-based system typically showed less reduced OAR sparing; however, the advantage of the system is shown if soft tissue contrast is needed. PTV coverage remained comparable across all platforms.

OsCM regulates rice defence system in response to UV light supplemented with drought stress

Studies on plant responses to combined abiotic stresses are very limited, especially in major crop plants. The current study evaluated the response of chorismate mutase overexpressor (OxCM) rice line to combined UV light and drought stress. The experiments were conducted in pots in a growth chamber, and data were assessed for gene expression, antioxidant and hormone regulation, flavonoid accumulation, phenotypic variation, and amino acid accumulation. Wild-type (WT) rice had reduced the growth and vigour, while transgenic rice maintained growth and vigour under combined UV light and drought stress. ROS and lipid peroxidation analysis revealed that chorismate mutase (OsCM) reduced oxidative stress mediated by ROS scavenging and reduced lipid peroxidation. The combined stresses reduced biosynthesis of total flavonoids, kaempferol and quercetin in WT plants, but increased significantly in plants with OxCM. Phytohormone analysis showed that SA was reduced by 50% in WT and 73% in transgenic plants, while ABA was reduced by 22% in WT plants but increased to 129% in transgenic plants. Expression of chorismate mutase regulates phenylalanine biosynthesis, UV light and drought stress-responsive genes, e.g., phenylalanine ammonia lyase (OsPAL), dehydrin (OsDHN), dehydration-responsive element-binding (OsDREB), ras-related protein 7 (OsRab7), ultraviolet-B resistance 8 (OsUVR8), WRKY transcription factor 89 (OsWRKY89) and tryptophan synthase alpha chain (OsTSA). Moreover, OsCM also increases accumulation of free amino acids (aspartic acid, glutamic acid, leucine, tyrosine, phenylalanine and proline) and sodium (Na), potassium (K), and calcium (Ca) ions in response to the combined stresses. Together, these results suggest that chorismate mutase expression induces physiological, biochemical and molecular changes that enhance rice tolerance to combined UV light and drought stresses.

Improved Performance of Organic Thermoelectric Generators Through Interfacial Energetics

The interfacial energetics are known to play a crucial role in organic diodes, transistors, and sensors. Designing the metal-organic interface has been a tool to optimize the performance of organic (opto)electronic devices, but this is not reported for organic thermoelectrics. In this work, it is demonstrated that the electrical power of organic thermoelectric generators (OTEGs) is also strongly dependent on the metal-organic interfacial energetics. Without changing the thermoelectric figure of merit (ZT) of polythiophene-based conducting polymers, the generated power of an OTEG can vary by three orders of magnitude simply by tuning the work function of the metal contact to reach above 1000 µW cm^-2 . The effective Seebeck coefficient (S_eff ) of a metal/polymer/metal single leg OTEG includes an interfacial contribution (V_inter /ΔT) in addition to the intrinsic bulk Seebeck coefficient of the polythiophenes, such that S_eff  = S + V_inter /ΔT varies from 22.7 µV K^-1 [9.4 µV K^-1 ] with Al to 50.5 µV K^-1 [26.3 µV K^-1 ] with Pt for poly(3,4-ethylenedioxythiophene):p-toluenesulfonate [poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate)]. Spectroscopic techniques are used to reveal a redox interfacial reaction affecting locally the doping level of the polymer at the vicinity of the metal-organic interface and conclude that the energetics at the metal-polymer interface provides a new strategy to enhance the performance of OTEGs.

Deep Learning of Time-Signal Intensity Curves from Dynamic Susceptibility Contrast Imaging Enables Tissue Labeling and Prediction of Survival in Glioblastoma

BACKGROUND AND PURPOSE

An autoencoder can learn representative time-signal intensity patterns to provide tissue heterogeneity measures using dynamic susceptibility contrast MR imaging. The aim of this study was to investigate whether such an autoencoder-based pattern analysis could provide interpretable tissue labeling and prognostic value in isocitrate dehydrogenase (IDH) wild-type glioblastoma.

MATERIALS AND METHODS

Preoperative dynamic susceptibility contrast MR images were obtained from 272 patients with IDH wild-type glioblastoma (training and validation, 183 and 89 patients, respectively). The autoencoder was applied to the dynamic susceptibility contrast MR imaging time-signal intensity curves of tumor and peritumoral areas. Representative perfusion patterns were defined by voxelwise K-means clustering using autoencoder latent features. Perfusion patterns were labeled by comparing parameters with anatomic reference tissues for baseline, signal drop, and percentage recovery. In the validation set (n = 89), a survival model was created from representative patterns and clinical predictors using Cox proportional hazard regression analysis, and its performance was calculated using the Harrell C-index.

RESULTS

Eighty-nine patients were enrolled. Five representative perfusion patterns were used to characterize tissues as high angiogenic tumor, low angiogenic/cellular tumor, perinecrotic lesion, infiltrated edema, and vasogenic edema. Of these, the low angiogenic/cellular tumor (hazard ratio, 2.18; P = .047) and infiltrated edema patterns (hazard ratio, 1.88; P = .009) in peritumoral areas showed significant prognostic value. The combined perfusion patterns and clinical predictors (C-index, 0.72) improved prognostication when added to clinical predictors (C-index, 0.55).

CONCLUSIONS

The autoencoder perfusion pattern analysis enabled tissue characterization of peritumoral areas, providing heterogeneity and dynamic information that may provide useful prognostic information in IDH wild-type glioblastoma.

Draft Genome Sequences of 27 Rhizogenic Agrobacterium Biovar 1 Strains, the Causative Agent of Hairy Root Disease

Rhizogenic Agrobacterium biovar 1 strains are important plant pathogens that cause hairy root disease in Cucurbitaceae and Solanaceae crops cultivated under hydroponic conditions. In contrast to tumorigenic agrobacteria, only a few genome sequences of rhizogenic agrobacteria are currently available. Here, we report the draft genome sequences of 27 rhizogenic Agrobacterium strains.

Abstract 4006: TRX-221, a novel 4th-generation EGFR inhibitor for overcoming C797S mutation-mediated acquired resistance in NSCLC

Targeting mutated EGFR is a clinically validated approach for tackling non-small cell lung cancer (NSCLC). Approximately 20% of patients with advanced NSCLC harbor an EGFR mutation. Osimertinib is a 3rd-generation oral EGFR-TKI targeting the EGFR sensitizing mutations Del19 and L858R, as well as an acquired mutation, T790M. Despite osimertinib's efficacy in NSCLC, resistance develops and the mechanisms of resistance to osimertinib are complex. Development of another mutation, C797S is the most common mechanism of acquired resistance following osimertinib treatment. This mutation occurs with about 12% frequency after a 1L therapy of osimertinib, and with approximately 17% frequency after a 2L therapy. Here, we report TRX-221 as a novel 4th-generation EGFR-TKI that can overcome C797S-mediated acquired resistance in NSCLC models in vitro and in vivo. TRX-221 exhibited potent inhibitory activity against multiple EGFR mutant kinases, including Del19/T790M/C797S, L858R/T790M/C797S, Del19/C797S, L858R/C797S, Del19/T790M, L858R/T790M, Del19, and L858R. Likewise, TRX-221 potently inhibited the proliferation of Ba/F3 cells stably overexpressing these eight EGFR mutants. TRX-221 however showed sparing activity against EGFR wild-type kinase and cell lines. TRX-221 also demonstrated marked anti-proliferative activity against osimertinib-resistant patient-derived cancer cell lines (PDCs). With favorable DMPK profiles, once-daily oral dosing of TRX-221 induced strong anti-tumor effects in a dose-dependent manner in a variety of osimertinib-resistant CDX and PDX models. As a reversible, selective, and broad-spectrum 4th-generation EGFR-TKI, TRX-221 is currently undergoing IND-enabling studies and shows strong potential as a therapeutic solution to treat advanced NSCLC patients harboring EGFR mutations.

Citation Format: Sumin Lim, Seulgi Choi, Ju-Kyung Lee, Eunhyun Choi, Sungwon Lee, Kwangwoo Chun, Myoungki Baek, Jiyeon Park, Jihyun Kim, Areum Kang, Younghoon Kim, Namkyoung Kim, Byoungchul Cho, Taebo Sim, Koo Lee. TRX-221, a novel 4th-generation EGFR inhibitor for overcoming C797S mutation-mediated acquired resistance in NSCLC. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4006.

National trends in suicide-related behaviors among youths between 2005-2020, including COVID-19: a Korean representative survey of one million adolescents

OBJECTIVE

It is difficult to conclude that COVID-19 is associated with a decrease in the suicide attempts rate by comparing only a short-term period. Therefore, it is necessary to examine attempted suicide rates through a trend analysis over a longer period. This study aimed to investigate an estimated long-term trend regarding the prevalence of suicide-related behaviors among adolescents in South Korea from 2005 to 2020, including COVID-19.

SUBJECTS AND METHODS

We sourced data from a national representative survey (Korea Youth Risk Behavior Survey) and analyzed one million Korean adolescents aged 13 to 18 years (n=1,057,885) from 2005 to 2020. The 16-year trends regarding the prevalence of sadness or despair and suicidal ideation and attempt and the trend changes before and during COVID-19.

RESULTS

Data of 1,057,885 Korean adolescents was analyzed (weighted mean age, 15.03 years; males, 52.5%; females, 47.5%). Although the 16-year trend in the prevalence of sadness or despair and suicide ideation and attempt consistently decreased (prevalence of sadness or despair between 2005-2008, 38.0% with 95% confidence interval [CI], 37.7 to 38.4 vs. prevalence in 2020, 25.0% [24.5 to 25.6]; suicide ideation between 2005-2008, 21.9% [21.6 to 22.1] vs. prevalence in 2020, 10.7% [10.3 to 11.1]; and suicide attempt between 2005-2008, 5.0% [4.9 to 5.2] vs. prevalence in 2020, 1.9% [1.8 to 2.0]), the downward slope decreased during COVID-19 (βdiff in sadness, 0.215 with 95% CI 0.206 to 0.224; βdiff in suicidal ideation, 0.245 [0.234 to 0.256]; and βdiff in suicide attempt, 0.219 [0.201 to 0.237]) compared with pre-pandemic period.

CONCLUSIONS

This study found that the observed risk of suicide-related behaviors during the pandemic was higher than expected through long-term trend analysis of the prevalence of sadness/despair and suicidal ideation and attempts among South Korean adolescents. We need a profound epidemiologic study of the change in mental health due to the pandemic's impact and the establishment of prevention strategies for suicide ideation and attempt.

Identification of Thiazolo[5,4-b]pyridine Derivatives as c-KIT Inhibitors for Overcoming Imatinib Resistance

c-KIT is a promising therapeutic target against gastrointestinal stromal tumor (GIST). In order to identify novel c-KIT inhibitors capable of overcoming imatinib resistance, we synthesized 31 novel thiazolo[5,4-b]pyridine derivatives and performed SAR studies. We observed that, among these substances, 6r is capable of inhibiting significantly c-KIT and suppressing substantially proliferation of GIST-T1 cancer cells. It is of note that 6r is potent against a c-KIT V560G/D816V double mutant resistant to imatinib. Compared with sunitinib, 6r possesses higher differential cytotoxicity on c-KIT D816V Ba/F3 cells relative to parental Ba/F3 cells. In addition, kinase panel profiling reveals that 6r has reasonable kinase selectivity. It was found that 6r remarkably attenuates proliferation of cancer cells via blockade of c-KIT downstream signaling, and induction of apoptosis and cell cycle arrest. Furthermore, 6r notably suppresses migration and invasion, as well as anchorage-independent growth of GIST-T1 cells. This study provides useful SAR information for the design of novel c-KIT inhibitors overcoming imatinib-resistance.

Longitudinal alterations in gamma-aminobutyric acid (GABAA) receptor availability over ∼ 1 year following traumatic brain injury

Longitudinal alterations of gamma-aminobutyric acid (GABA_A) receptor availability following traumatic brain injury have remained uncharacterized and may reflect changes in neuronal structure and function linked to cognitive recovery. We measured GABA_A receptor availability using the tracer [11C]flumazenil in nine adults with traumatic brain injury (3–6 months after injury, subacute scan) and in 20 non-brain-injured individuals. A subset of subjects with traumatic brain injury (n = 7) were scanned at a second chronic time-point, 7–13 months after their first scan; controls (n = 9) were scanned for a second time, 5–11 months after the first scan. After accounting for atrophy in subjects with traumatic brain injury, we find broad decreases in GABA_A receptor availability predominantly within the frontal lobes, striatum, and posterior-medial thalami; focal reductions were most pronounced in the right insula and anterior cingulate cortex (p < 0.05). Greater relative increase, compared to controls, in global GABA_A receptor availability appeared between subacute and chronic scans. At chronic scan (>1 year post-injury), we find increased pallidal receptor availability compared to controls. Conversely, receptor availability remained depressed across the frontal cortices. Longitudinal improvement in executive attention correlated with increases in receptor availability across bilateral fronto-parietal cortical regions and the anterior-lateral aspects of the thalami. The specific observations of persistent bi-frontal lobe reductions and bilateral pallidal elevation are consistent with the anterior forebrain mesocircuit hypothesis for recovery of consciousness following a wide range of brain injuries; our results provide novel correlative data in support of specific cellular mechanisms underlying persistent cognitive deficits. Collectively, these measurements support the use of [11C]flumazenil to track recovery of large-scale network function following brain injuries and measure response to therapeutics.

Trends in body mass index changes among Korean adolescents between 2005-2020, including the COVID-19 pandemic period: a national representative survey of one million adolescents

OBJECTIVE

The impact of the coronavirus disease 2019 (COVID-19) pandemic on weight gain in children and adolescents remains unknown. We aimed to identify an estimated 15-year trend in mean body mass index (BMI) changes and prevalence of obesity and overweight among Korean adolescents from 2005 to 2020, including the period of the COVID-19 pandemic.

PATIENTS AND METHODS

We analyzed data taken from a nationwide survey (Korea Youth Risk Behavior Survey), between 2005 and 2020. Representative samples of one million Korean adolescents aged 13-18 years (n=1,057,885) were examined. The 15-year trends in mean BMI and proportion of obesity or overweight, and the changes due to the COVID-19 pandemic were analyzed.

RESULTS

The data of 1,057,885 Korean adolescents were analyzed (mean age: 14.98 years; females, 48.4%). The estimated weighted mean BMI was 20.5 kg/m2 [95% confidence interval (CI), 20.4-20.5] from 2005 to 2008 and 21.5 kg/m2 (95% CI, 21.4-21.6) in 2020 (during the COVID-19 pandemic). Although the 15-year trend of mean BMI gradually increased, the change in mean BMI before and during the pandemic significantly lessened (βdiff, -0.027; 95% CI, -0.028 to -0.026). The 15-year (2005-2020) trend changes in the prevalence of obesity and overweight were similar (obesity prevalence from 2005-2008, 3.2%; 95% CI, 3.1-3.3 vs. obesity prevalence in 2020, 8.6%; 95% CI, 8.2-9.0; βdiff, -0.309; 95% CI, -0.330 to -0.288).

CONCLUSIONS

The 15-year trend of overall mean BMI and obesity and overweight prevalence demonstrated a significant increase; however, its slope decreased during the pandemic. These landmark results suggest the need for the development of precise strategies to prevent pediatric obesity and overweight during the COVID-19 pandemic.

Identification of Pyridinyltriazine Derivatives as Potent panFGFR Inhibitors against Gatekeeper Mutants for Overcoming Drug Resistance

Although FGFR inhibitors hold promise in treating various cancers, resistance to the FGFR inhibitors caused by acquired secondary mutations has emerged. To discover novel FGFR inhibitors capable of inhibiting FGFR mutations, including gatekeeper mutations, we designed and synthesized several new pyridinyltriazine derivatives. A structure-activity relationship (SAR) study led to the identification of 17a as a highly potent panFGFR inhibitor against wild-type and mutant FGFRs. Notably, 17a is superior to infigratinib in terms of kinase-inhibitory and cellular activities, especially against V555M-FGFR3. Molecular dynamics simulations provide a clear understanding of why pyridinyltraizine derivative 17a possesses activity against V555M-FGFR3. Moreover, 17a significantly suppresses proliferation of cancer cells harboring FGFR mutations via FGFR signaling blockade, cell cycle arrest, and apoptosis. Furthermore, 17a and 17b exhibited remarkable efficacies in TEL-V555M-FGFR3 Ba/F3 xenograft mouse model and 17a is more efficacious than infigratinib. This study provides new insight into the design of novel FGFR inhibitors that are active against FGFR mutants.

Novel Macrocyclic Peptidomimetics Targeting the Polo-Box Domain of Polo-Like Kinase 1

The polo-box domain (PBD) of Plk1 is a promising target for cancer therapeutics. We designed and synthesized novel phosphorylated macrocyclic peptidomimetics targeting PBD based on acyclic phosphopeptide PMQSpTPL. The inhibitory activities of 16e on Plk1-PBD is >30-fold higher than those of PMQSpTPL. Both 16a and 16e possess excellent selectivity for Plk1-PBD over Plk2/3-PBD. Analysis of the cocrystal structure of Plk1-PBD in complex with 16a reveals that the 3-(trifluoromethyl)benzoyl group in 16a interacts with Arg516 through a π-stacking interaction. This π-stacking interaction, which has not been reported previously, provides insight into the design of novel and potent Plk1-PBD inhibitors. Furthermore, 16h, a PEGlyated macrocyclic phosphopeptide derivative, induces Plk1 delocalization and mitotic failure in HeLa cells. Also, the number of phospho-H3-positive cells in a zebrafish embryo increases in proportion to the amount of 16a. Collectively, the novel macrocyclic peptidomimetics should serve as valuable templates for the design of potent and novel Plk1-PBD inhibitors.

Hypovascular Cellular Tumor in Primary Central Nervous System Lymphoma is Associated with Treatment Resistance: Tumor Habitat Analysis Using Physiologic MRI

BACKGROUND AND PURPOSE

The microenvironment of lymphomas is known to be highly variable and closely associated with treatment resistance and survival. We tried to develop a physiologic MR imaging-based spatial habitat analysis to identify regions associated with treatment resistance to facilitate the prediction of tumor response after initial chemotherapy in patients with primary central nervous system lymphoma.

MATERIALS AND METHODS

Eighty-one patients with pathologically confirmed primary central nervous system lymphoma were enrolled. Pretreatment physiologic MR imaging was performed, and K-means clustering was used to separate voxels into 3 spatial habitats according to ADC and CBV values. Associations of spatial habitats and clinical and conventional imaging predictors with time to progression were analyzed using Cox proportional hazards modeling. The performance of statistically significant predictors for time to progression was assessed using the concordance probability index.

RESULTS

The 3 spatial habitats of hypervascular cellular tumor, hypovascular cellular tumor, and hypovascular hypocellular tumor were identified. A large hypovascular cellular habitat was most significantly associated with short time to progression (hazard ratio, 2.83; P = . 017). The presence of an atypical finding (hazard ratio, 4.41; P = . 016), high performance score (hazard ratio, 5.82; P = . 04), and high serum lactate dehydrogenase level (hazard ratio, 1.01; P = .013) was significantly associated with time to progression. A predictive model constructed using the habitat score and other imaging parameters showed a concordance probability index for prediction of time to progression of 0.70 (95% CI, 0.54-0.87).

CONCLUSIONS

A hypovascular cellular tumor habitat is associated with treatment resistance in primary central nervous system lymphoma, and its assessment may refine prechemotherapy imaging-based response prediction for patients with primary central nervous system lymphoma.

Novel Small Molecules Capable of Blocking mtRAS-Signaling Pathway

RAS mutants are involved in approximately 30% of all human cancers and have been regarded as undruggable targets owing to relatively smooth protein surface and obscure binding pockets. In our previous study, we have demonstrated that GNF-7, a multi-targeted kinase inhibitor, possesses potent anti-proliferative activity against Ba/F3 cells transformed with NRAS-G12D. Based on our further analysis using Ba/F3 cells transformed with mtRAS, we discovered a series of pyrimido[4,5-d]pyrimidin-2-one analogues as mtRAS-signaling pathway blockers. In addition, our efforts expanded the assessment to cancer cells with mtRAS, which revealed that these substances are also capable of strongly suppressing the proliferation of various cancer cells harboring KRAS-G12D (AsPC-1), KRAS-G12V (SW480, DU-145), KRAS-G12C (H358), KRAS-G13D (MDA-MB-231), KRAS-Q61L (HT-29), and NRAS-Q61L (OCI-AML3). We herein report novel and potent mtRAS-signaling pathway blockers, SIJ1795 and SIJ1772, possessing 2 to 10-fold increased anti-proliferative activities compared to those of GNF-7 on cancer cells harboring mtRAS as well as on Ba/F3 cells transformed with mtRAS. Both SIJ1795 and SIJ1772 attenuate phosphorylation of RAS downstream molecules (AKT and MEK) and induce apoptosis and G0/G1 cell cycle arrest on cancer cells with mtRAS. Moreover, both substances substantially suppress the migration, invasion, and colony formation of cancer cells harboring mtRAS. Taken together, this study led us to identification of SIJ1795 and SIJ1772 capable of strongly inhibiting mtRAS-signaling pathway on cancer cells harboring mtRAS.

Carotid Plaque Composition Assessed by CT Predicts Subsequent Cardiovascular Events among Subjects with Carotid Stenosis

BACKGROUND AND PURPOSE

Currently, the characteristics of carotid plaques are considered important factors for identifying subjects at high risk of stroke. This study aimed to test the hypothesis that carotid plaque composition assessed by CTA is associated with an increased risk of future major adverse cardiovascular events among asymptomatic subjects with moderate-to-severe carotid artery stenosis.

MATERIALS AND METHODS

This single-center, retrospective cohort study included 194 carotid plaques from 176 asymptomatic subjects with moderate-to-severe carotid artery stenosis. The association of CTA-determined plaque composition with the risk of subsequent adverse cardiovascular events was analyzed.

RESULTS

During a median follow-up of 41 months, the adverse cardiovascular event incidence among 194 carotid plaques was 19.6%. There were significant differences in plaque Hounsfield units (P < .001) and spotty calcium presence (P < .001) between carotid plaques from subjects with and without subsequent adverse cardiovascular events. Multivariable analysis revealed carotid plaque Hounsfield unit density (P < .001) and spotty calcium (P < .001) as independent predictors of subsequent adverse cardiovascular events. In association with moderate carotid artery stenosis, the plaque Hounsfield unit values were significantly lower among carotid plaques from subjects who experienced subsequent adverse cardiovascular events (P = .002), strokes (P = .01), and cardiovascular deaths (P = .04); the presence of spotty calcium was significantly associated with the occurrence of adverse cardiovascular events (P = .001), acute coronary syndrome (P = .01), and cardiovascular death (P = .04).

CONCLUSIONS

Carotid plaque Hounsfield unit density and spotty calcium were independent predictors of a greater risk of adverse cardiovascular event occurrence.

Anti-Tumor Activity of AZD4547 Against NTRK1 Fusion Positive Cancer Cells Through Inhibition of NTRKs

Inhibitors of tropomyosin-related kinases (TRKs) display remarkable outcomes in the regression of cancers harboring the Neurotrophin Receptors Tyrosine Kinase (NTRK) fusion gene. As a result, TRKs have become attractive targets in anti-cancer drug discovery programs. Here, we demonstrate that AZD4547, a highly potent and selective inhibitor of fibroblast growth factor receptor (FGFR), displays anti-tumor activity against KM12(Luc) harboring the TPM3-NTRK1 fusion gene associated with its direct inhibition of TRKs. The results of profiling, using a 64-member in-house cancer cell panel, show that AZD4547 displays anti-proliferation activity against KM12(Luc) with a GI₅₀ of 100 nM. In vitro biochemical assays reveal that AZD4547 has IC₅₀ values of 18.7, 22.6 and 2.9 nM against TRKA, B and C, respectively. In a cellular context, AZD4547 blocks auto-phosphorylation of TRKs and phosphorylation of its downstream molecules including PLC-gamma and AKT in a dose dependent manner. Also, AZD4547 at 0.1 μM concentration downregulates expression of MAPK target genes (DUSP6, CCND1 and ETV1) as well as the E2F pathway. Furthermore, AZD4547 induces G0/G1 arrest and apoptosis, and suppresses anchorage independent growth of KM12(Luc). Oral administration of 40 mpk AZD4547 dramatically delays tumor growth in a KM12(Luc) implemented xenograft model, without promoting body weight changes. The capability of AZD4547 to inhibit TRKA, TRKB and clinically relevant mutants (TRKA G595R, G667S, G667C and G667A) was also evaluated using Ba/F3 cells harboring the ETV6-NTRKs fusion gene. The combined observations demonstrate the potential application of AZD4547 for treatment of NTRK fusion driven cancers.

A study on accumulator analysis for the valve performance evaluation system of nuclear power plants

To evaluate the valves used in the nuclear power plants are working properly under the required conditions, the performance and capacity test should be performed. In the test system, the accumulator was employed to control the large amount of high pressure and high temperature steam generated in the boiler precisely. In the accumulating process, the steam is often condensed. In order to prevent condensation, it is needed to install heaters and preheat the accumulator. However, if the size of the accumulator becomes large, the installation of the heater may not be easy. Therefore, when the test is conducted, the system was preheated by the latent heat generated from the phase change. Insufficient thermal insulation may cause temperature differences and it can cause mechanical problems in the accumulator structure. If insulation is sufficient, the temperature difference is indicated by the height. As the cooled condensate moves downwards, the condensate is discharged by the drain valve control and the temperature difference of the structure can be disappeared. The results of this paper can be applied to the conceptualization of equipment that uses latent heat and for the design of high-precision steam experimental devices or the design of high-capacity steam utilization systems.

Association of low skeletal muscle mass with the presence of advanced colorectal neoplasm: integrative analysis using three skeletal muscle mass indices

AIM

This study aimed to evaluate an association between colorectal neoplasm (CRN) and skeletal muscle mass using three widely accepted skeletal muscle mass indices (SMIs) in a large population at average risk.

METHOD

We performed a cross-sectional study using a screening colonoscopy database of 33 958 asymptomatic subjects aged 40-75 years. Appendicular skeletal muscle mass (ASM) was measured using a bioelectrical impedance analyser. ASM adjusted for height squared (ASM/ht² ), weight (ASM/wt) and body mass index (ASM/BMI) were used as indices for muscle mass. Logistic regression models were used to evaluate the association between SMIs and CRN.

RESULTS

In a multivariable-adjusted model, the risk of an advanced CRN increased linearly with decreasing quartiles for all three SMIs. The adjusted odds ratios (ORs) for advanced CRN in quartiles 1, 2 and 3 of ASM/wt compared with that in quartile 4 were 1.279, 1.196 and 1.179, respectively (P_trend  = 0.017); for ASM/BMI, ORs were 1.307, 1.144 and 1.091, respectively (P_trend  = 0.002); and for ASM/ht² , ORs were 1.342, 1.169 and 1.062, respectively (P_trend  = 0.002). The risk of distally located advanced CRN was higher in quartile 1 than in quartile 4 for all three SMIs (ASM/wt, OR = 1.356; ASM/BMI, OR = 1.383; ASM/ht² , OR = 1.430).

CONCLUSION

Our study demonstrated that low skeletal muscle mass was consistently associated with the presence of advanced CRN in a population at average risk regardless of the operational definition of the SMI, and it was particularly associated with distal advanced CRN.

Geospatial Distribution and Predictors of Mortality in Hospitalized Patients With COVID-19: A Cohort Study

BACKGROUND

The global coronavirus disease 2019 (COVID-19) pandemic offers the opportunity to assess how hospitals manage the care of hospitalized patients with varying demographics and clinical presentations. The goal of this study was to demonstrate the impact of densely populated residential areas on hospitalization and to identify predictors of length of stay and mortality in hospitalized patients with COVID-19 in one of the hardest hit counties internationally.

METHODS

This was a single-center cohort study of 1325 sequentially hospitalized patients with COVID-19 in New York between March 2, 2020, to May 11, 2020. Geospatial distribution of study patients' residences relative to population density in the region were mapped, and data analysis included hospital length of stay, need and duration of invasive mechanical ventilation (IMV), and mortality. Logistic regression models were constructed to predict discharge dispositions in the remaining active study patients.

RESULTS

The median age of the study cohort (interquartile range [IQR]) was 62 (49-75) years, and more than half were male (57%) with history of hypertension (60%), obesity (41%), and diabetes (42%). Geographic residence of the study patients was disproportionately associated with areas of higher population density (r s = 0.235; P = .004), with noted "hot spots" in the region. Study patients were predominantly hypertensive (MAP > 90 mmHg; 670, 51%) on presentation with lymphopenia (590, 55%), hyponatremia (411, 31%), and kidney dysfunction (estimated glomerular filtration rate < 60 mL/min/1.73 m2; 381, 29%). Of the patients with a disposition (1188/1325), 15% (182/1188) required IMV and 21% (250/1188) developed acute kidney injury. In patients on IMV, the median (IQR) hospital length of stay in survivors (22 [16.5-29.5] days) was significantly longer than that of nonsurvivors (15 [10-23.75] days), but this was not due to prolonged time on the ventilator. The overall mortality in all hospitalized patients was 15%, and in patients receiving IMV it was 48%, which is predicted to minimally rise from 48% to 49% based on logistic regression models constructed to project disposition in the remaining patients on ventilators. Acute kidney injury during hospitalization (odds ratioE, 3.23) was the strongest predictor of mortality in patients requiring IMV.

CONCLUSIONS

This is the first study to collectively utilize the demographics, clinical characteristics, and hospital course of COVID-19 patients to identify predictors of poor outcomes that can be used for resource allocation in future waves of the pandemic.