Machine-Learning-Driven High-Throughput Screening for High-Energy Density and Stable NASICON Cathodes.

The Na super ionic conductor (NASICON), which has outstanding structural stability and a high operating voltage, is an appealing material for overcoming the limits of low specific energy and larger volume distortion of sodium-ion batteries. In this study, to discover ideal NASICON cathode materials, a screening platform based on density functional theory (DFT) calculations and machine learning (ML) is developed. A training database was generated utilizing the previous 124 545 electrode databases, and a test set of 3126 potential NASICON structures [NaxMyM'1-y(PO4)3] with 27 dopants at the metal site and 6 dopants at the polyanion central site was constructed. The developed ML surrogate model identifies 796 materials that satisfy the following criteria: formation energy of <0.0 eV/atom, energy above hull of ≤0.025 eV/atom, volume change of ≤4%, and theoretical capacity of ≥50 mAh/g. The thermodynamically stable configurations of doped NASICON structures were then selected using machine learning interatomic potential (MLIP), enabling rapid consideration of various dopant site configurations. DFT calculations are followed on 796 screened materials to obtain energy density, average voltage, and volume change. Finally, 50 candidates with an average voltage of ≥3.5 V are identified. The suggested platform accelerates the exploration for optimal NASICON materials by narrowing the focus on materials with desired properties, saving considerable resources.

Changes in food sufficiency among Korean adults in urban and rural areas during the COVID-19 pandemic: an analysis of the 7th and 8th Korea National Health and Nutrition Examination Survey.

Objectives: Understanding changes in food sufficiency within various demographic groups during emergency situations, such as the global coronavirus disease 2019 (COVID-19) pandemic, is crucial in formulating public health policies for future preparedness. This study investigated potential differences between urban and rural residents in food sufficiency trends during the COVID-19 pandemic and examined how these changes varied according to sociodemographic factors. Methods: This cross-sectional study analyzed data from 19,724 adults aged 20 years and older, utilizing information from the 7th-8th Korea National Health and Nutrition Examination Survey (2018-2021). Results: In urban areas, across all subpopulations, food sufficiency improved significantly during the COVID-19 period relative to pre-pandemic levels (p<0.001). However, in rural regions, a significant increase in food sufficiency during the COVID-19 era was observed only among women, with an odds ratio of 1.42 (confidence interval, 1.06 to 1.89). Nevertheless, no significant interaction terms were found between region and various sociodemographic factors regarding changes in food sufficiency during the COVID-19 period. Conclusion: During the COVID-19 pandemic, food sufficiency among urban residents improved compared to the pre-pandemic era, whereas their rural counterparts saw no such improvement. Additionally, no significant interaction was detected between urban versus rural areas and changes in food sufficiency during the COVID-19 period. These findings indicate the need for targeted food policies to prepare for potential future pandemics, particularly in rural areas, where food sufficiency did not improve.

Relationship of computed tomography-based measurements with symptom perception and quality of life in patients with severe asthma.

BACKGROUND: Symptom perception and quality of life (QOL) are important domains for properly managing severe asthma. This study aimed to assess the relationship between airway structural and parenchymal variables measured using chest computed tomography (CT) and subjective symptom perception and QOL in patients with severe asthma enrolled in the Korean Severe Asthma Registry. METHODS: This study used CT-based objective measurements, including airway wall thickness (WT), hydraulic diameter, functional small airway disease (fSAD), and emphysematous lung (Emph), to assess their association with subjective symptom (cough, dyspnea, wheezing, and sputum) perception measured using the visual analog scale, and QOL measured by the Severe Asthma Questionnaire (SAQ). RESULTS: A total of 94 patients with severe asthma were enrolled in this study. The WT and fSAD% were significantly positively associated with cough and dyspnea, respectively. For QOL, WT and Emph% showed significant negative associations with the SAQ. However, there was no significant association between lung function and symptom perception or between lung function and QOL. CONCLUSION: Overall, WT, fSAD%, and Emph% measured using chest CT were associated with subjective symptom perception and QOL in patients with severe asthma. This study provides a basis for clarifying the clinical correlates of imaging-derived metrics and for understanding the mechanisms of respiratory symptom perception.

Repulsive Sema3E-Plexin-D1 signaling coordinates both axonal extension and steering via activating an autoregulatory factor, Mtss1.

Axon guidance molecules are critical for neuronal pathfinding because they regulate directionality and growth pace during nervous system development. However, the molecular mechanisms coordinating proper axonal extension and turning are poorly understood. Here, metastasis suppressor 1 (Mtss1), a membrane protrusion protein, ensured axonal extension while sensitizing axons to the Semaphorin 3E (Sema3E)-Plexin-D1 repulsive cue. Sema3E-Plexin-D1 signaling enhanced Mtss1 expression in projecting striatonigral neurons. Mtss1 localized to the neurite axonal side and regulated neurite outgrowth in cultured neurons. Mtss1 also aided Plexin-D1 trafficking to the growth cone, where it signaled a repulsive cue to Sema3E. Mtss1 ablation reduced neurite extension and growth cone collapse in cultured neurons. Mtss1-knockout mice exhibited fewer striatonigral projections and irregular axonal routes, and these defects were recapitulated in Plxnd1- or Sema3e-knockout mice. These findings demonstrate that repulsive axon guidance activates an exquisite autoregulatory program coordinating both axonal extension and steering during neuronal pathfinding.

Maternal nanoplastic ingestion induces an increase in offspring body weight through altered lipid species and microbiota.

The rapidly increasing prevalence of obesity and overweight, especially in children and adolescents, has become a serious societal issue. Although various genetic and environmental risk factors for pediatric obesity and overweight have been identified, the problem has not been solved. In this study, we examined whether environmental nanoplastic (NP) pollutants can act as environmental obesogens using mouse models exposed to NPs derived from polystyrene and polypropylene, which are abundant in the environment. We found abnormal weight gain in the progeny until 6 weeks of age following the oral administration of NPs to the mother during gestation and lactation. Through a series of experiments involving multi-omic analyses, we have demonstrated that NP-induced weight gain is caused by alterations in the lipid composition (lysophosphatidylcholine/phosphatidylcholine ratio) of maternal breast milk and he gut microbiota distribution of the progeny. These data indicate that environmental NPs can act as obesogens in childhood.

Bionic artificial skin with a fully implantable wireless tactile sensory system for wound healing and restoring skin tactile function.

Tactile function is essential for human life as it enables us to recognize texture and respond to external stimuli, including potential threats with sharp objects that may result in punctures or lacerations. Severe skin damage caused by severe burns, skin cancer, chemical accidents, and industrial accidents damage the structure of the skin tissue as well as the nerve system, resulting in permanent tactile sensory dysfunction, which significantly impacts an individual's daily life. Here, we introduce a fully-implantable wireless powered tactile sensory system embedded artificial skin (WTSA), with stable operation, to restore permanently damaged tactile function and promote wound healing for regenerating severely damaged skin. The fabricated WTSA facilitates (i) replacement of severely damaged tactile sensory with broad biocompatibility, (ii) promoting of skin wound healing and regeneration through collagen and fibrin-based artificial skin (CFAS), and (iii) minimization of foreign body reaction via hydrogel coating on neural interface electrodes. Furthermore, the WTSA shows a stable operation as a sensory system as evidenced by the quantitative analysis of leg movement angle and electromyogram (EMG) signals in response to varying intensities of applied pressures.

Highly Sensitive Real-Time Monitoring of Adenosine Receptor Activities in Nonsmall Cell Lung Cancer Cells Using Carbon Nanotube Field-Effect Transistors.

Adenosine metabolism through adenosine receptors plays a critical role in lung cancer biology. Although recent studies showed the potential of targeting adenosine receptors as drug targets for lung cancer treatment, conventional methods for investigating receptor activities often suffer from various drawbacks, including low sensitivity and slow analysis speed. In this study, adenosine receptor activities in nonsmall cell lung cancer (NSCLC) cells were monitored in real time with high sensitivity through a carbon nanotube field-effect transistor (CNT-FET). In this method, we hybridized a CNT-FET with NSCLC cells expressing A2A and A2B adenosine receptors to construct a hybrid platform. This platform could detect adenosine, an endogenous ligand of adenosine receptors, down to 1 fM in real time and sensitively discriminate adenosine among other nucleosides. Furthermore, we could also utilize the platform to detect adenosine in complicated environments, such as human serum. Notably, our hybrid platform allowed us to monitor pharmacological effects between adenosine and other drugs, including dipyridamole and theophylline, even in human serum samples. These results indicate that the NSCLC cell-hybridized CNT-FET can be a practical tool for biomedical applications, such as the evaluation and screening of drug-candidate substances.

Impaired neuronal activity as a potential factor contributing to the underdeveloped cerebrovasculature in a young Parkinson's disease mouse model.

Misfolding of α-synuclein (α-Syn) in the brain causes cellular dysfunction, leading to cell death in a group of neurons, and consequently causes the progression of Parkinson's disease (PD). Although many studies have demonstrated the pathological connections between vascular dysfunction and neurodegenerative diseases, it remains unclear how neuronal accumulation of α-Syn affects the structural and functional aspects of the cerebrovasculature to accelerate early disease progression. Here, we demonstrated the effect of aberrant α-Syn expression on the brain vasculature using a PD mouse model expressing a familial mutant form of human α-Syn selectively in neuronal cells. We showed that young PD mice have an underdeveloped cerebrovasculature without significant α-Syn accumulation in the vasculature. During the early phase of PD, toxic α-Syn was selectively increased in neuronal cells, while endothelial cell proliferation was decreased in the absence of vascular cell death or neuroinflammation. Instead, we observed altered neuronal activation and minor changes in the activity-dependent gene expression in brain endothelial cells (ECs) in young PD mice. These findings demonstrated that neuronal expression of mutant α-Syn in the early stage of PD induces abnormal neuronal activity and contributes to vascular patterning defects, which could be associated with a reduced angiogenic potential of ECs.

Factors predicting different times for brushing teeth during the day: multilevel analyses.

BACKGROUND: The most effective and simple intervention for preventing oral disease is toothbrushing. However, there is substantial variation in the timing of brushing teeth during the day. We aimed to identify a comprehensive set of predictors of toothbrushing after lunch and after dinner and estimated contextual (i.e., geographic) variation in brushing behavior at different times of the day. METHODS: We constructed a conceptual framework for toothbrushing by reviewing health behavior models. The main data source was the 2017 Community Health Survey. We performed a four-level random intercept logistic regression to predict toothbrushing behavior. (individual, household, Gi/Gun/Gu, and Si/Do). RESULTS: Individuals under 30 years of age had higher likelihood of brushing after lunch, while brushing after dinner was higher among those aged 40-79 years. People engaged in service/sales, agriculture/fishing/labor/mechanics, as well as student/housewife/unemployed were 0.60, 0.41, and 0.49 times less likely to brush their teeth after lunch, respectively, compared to those working in the office, but the gap narrowed to 0.97, 0.96, 0.94 for brushing after dinner. We also found significant area-level variations in the timing of brushing. CONCLUSIONS: Different patterns in association with various factors at individual-, household- and Si/Gun/Gu-levels with toothbrushing after lunch versus toothbrushing after dinner suggests a need for tailored interventions to improve toothbrushing behavior depending on the time of day.

Best-Fit Circle for the Replication of Humeral Head Anatomy in Total Shoulder Arthroplasty.

Background: Anatomic restoration of the humeral head is critical for successful shoulder replacement. Accurate measurements of the humeral head are essential for anatomic substitution. Purpose: To evaluate whether a best-fit circle of the humeral head, as determined from different projections of plain radiographs, can predict the humeral head implant size for either the left or right shoulder. Study Design: Descriptive laboratory study. Methods: Bilateral shoulder radiographs of 200 patients without arthropathy or other abnormal findings of the humeral head were evaluated. The best-fit circle was obtained based on 3 points: the medial and lateral endpoints of the anatomic neck and the lateral cortex below the greater tuberosity. This circle was drawn on 5 different radiographic projections (shoulder anteroposterior [AP], glenoid AP, outlet, axillary, and 30° caudal tilt) of the left and right shoulders of each patient, and the radius of each circle was measured. Agreement in the best-fit circle radius between the left and right shoulders was statistically analyzed using the intraclass correlation coefficient (ICC). There were 2 independent blinded observers who performed each measurement twice to evaluate inter- and intraobserver reliability. Results: Overall agreement in the radius between the right and left shoulders was excellent (all ICCs ≥0.990). The ICCs according to the radiographic view were 0.990 (95% CI, 0.986-0.993) for shoulder AP, 0.992 (95% CI, 0.989-0.995) for glenoid AP, 0.996 (95% CI, 0.994-0.997) for outlet, 0.994 (95% CI, 0.991-0.996) for axillary, and 0.993 (95% CI, 0.990-0.995) for 30° caudal tilt. Interobserver ICCs demonstrated a high level of precision: 0.987 (95% CI, 0.978-0.993) for shoulder AP, 0.986 (95% CI, 0.974-0.992) for glenoid AP, 0.974 (95% CI, 0.954-0.985) for outlet, 0.991 (95% CI, 0.984-0.995) for axillary, and 0.987 (95% CI, 0.977-0.993) for 30° caudal tilt. Intraobserver ICCs demonstrated excellent test-retest reliability: 0.983 (95% CI, 0.970-0.991) for shoulder AP, 0.989 (95% CI, 0.980-0.994) for glenoid AP, 0.987 (95% CI, 0.978-0.993) for outlet, 0.985 (95% CI, 0.973-0.991) for axillary, and 0.970 (95% CI, 0.947-0.983) for 30° caudal tilt. Conclusion: The best-fit circle to calculate the ideal size of a humeral head implant was able to be determined from different projections of plain radiographs. Clinical Relevance: Anatomic restoration of a deformed humeral head can be achieved using the best-fit circle of the contralateral humeral head as obtained from plain radiographs. This method can facilitate preoperative planning and postoperative evaluation in the anatomic restoration of the shoulder to avoid the problems of overstuffing.

Metallosis-Induced Conversion Shoulder Arthroplasty: A Unique Experience and Literature Review.

BACKGROUND: Total shoulder arthroplasty (TSA) can fail for several reasons, such as component loosening, periprosthetic fracture, instability, infection, soft tissue failure, or joint overstuffing. Severe metallosis without loose glenoid components after TSA may result in the need for revision to reverse TSA. CASE PRESENTATION: Four years before the current presentation, an 86-year-old woman suffered from right shoulder pain and swelling. The initial diagnosis was osteoarthritis of the shoulder joint, for which she underwent TSA. Four years later, she complained of shoulder joint pain, swelling, and limited range of motion. On sonography, subscapularis and supraspinatus tendon tears were identified. Plain radiographs and computed tomography (CT) scans showed metallosis around the shoulder joint. Due to the rocking horse mechanism, wear of the upper portion of the glenoid component and bearing caused a foreign-body reaction and severe metallosis around the joint. Due to a massive rotator cuff tear combined with glenoid component wear, the patient eventually underwent reverse TSA (RTSA) and was satisfied with the final results. CONCLUSIONS: Severe metallosis due to glenoid component wear combined with a massive rotator cuff tear in TSA may cause the need for revision to RTSA.

Three-dimensional label-free visualization of the interactions of PM2.5 with macrophages and epithelial cells using optical diffraction tomography.

Particulate matter ≤ 2.5 µm (PM2.5) poses health risks related to various diseases and infections. However, the interactions between PM2.5 and cells such as uptake and cell responses have not been fully investigated despite advances in bioimaging techniques, because the heterogeneous morphology and composition of PM2.5 make it challenging to employ labeling techniques, such as fluorescence. In this work, we visualized the interaction between PM2.5 and cells using optical diffraction tomography (ODT), which provides quantitative phase images by refractive index distribution. Through ODT analysis, the interactions of PM2.5 with macrophages and epithelial cells, such as intracellular dynamics, uptake, and cellular behavior, were successfully visualized without labeling techniques. ODT analysis clearly shows the behavior of phagocytic macrophages and nonphagocytic epithelial cells for PM2.5. Moreover, ODT analysis could quantitatively compare the accumulation of PM2.5 inside the cells. PM2.5 uptake by macrophages increased substantially over time, but uptake by epithelial cells increased only marginally. Our findings indicate that ODT analysis is a promising alternative approach to visually and quantitatively understanding the interaction of PM2.5 with cells. Therefore, we expect ODT analysis to be employed to investigate the interactions of materials and cells that are difficult to label.

Nanoscale mapping of edge-state conductivity and charge-trap activity in topological insulators.

We report the nanoscale mapping of topological edge-state conductivity and the effects of charge-traps on conductivity in a Bi2Se3 multilayer film under ambient conditions. In this strategy, we applied an electric field perpendicular to the surface plane of Bi2Se3via a conducting probe to directly map the charge-trap densities and conductivities with a nanoscale resolution. The results showed that edge regions had one-dimensional characteristics with higher conductivities (two orders) and lower charge-trap densities (four orders) than those of flat surface regions where their conductivities and charge-traps were dominated by bulk effects. Additionally, edges showed an enhanced conductivity with an elevated electric field, possibly due to the creation of new topological states by stronger spin-Hall effects. Importantly, we observed ultra-high photoconductivity predominantly on edge regions compared with that of flat surface regions, which was attributed to the excitation of edge-state carriers by light. Since our method provides an important insight into the charge transport in topological insulators, it could be a significant advancement in the development of error-tolerant topotronic devices.

Combined effects of microplastics and benz[a]anthracene on cardiotoxicity in zebrafish (Danio rerio) larvae: Size matters.

The size of microplastics (MPs) plays an important role in combined toxic effects including synergistic or antagonistic effects. However, the influence of the size of MPs on the combined toxicity of contaminants remains unclear. In this study, we employed a zebrafish model to investigate the effects of MP size on the combined toxicity of benz[a]anthracene (BaA), a representative polyaromatic hydrocarbon, using three different sizes of polystyrene MPs (PSMPs) (0.2, 1.0, and 10 µm). Treatment of all groups did not result in any mortality of the zebrafish larvae. However, small-sized PSMPs (0.2 µm) enhanced the toxic effect of BaA in larvae such as cardiac defect and disruption of vessel formation. Medium-sized PSMPs (1.0 µm) were boundary in terms of the combined toxic effect; however, large-sized PSMPs (10 µm) alleviated the cardiotoxicity of BaA, including cardiac defect, ROS levels, and cell death. The combined effects showed a correlation with the body burden of MPs and BaA in larvae according to particle size (in the order of 0.2 µm > 1.0 µm > 10 µm). The synergistic effects occurred likely because the small PSMPs facilitated the body burden of BaA, induced excessive ROS by Ahr-mediated activity, and caused cell death in the heart, resulting in increased heart defects in the larvae. In contrast, large PSMPs abated the combined toxic effect through decreased body burden, whereas medium PSMPs form a boundary in combined effects. Therefore, the combined toxic effects of MPs are dependent on their size, which plays an important role in the transport and accumulation of environmental pollutants.

Differential particle and ion kinetics of silver nanoparticles in the lungs and biotransformation to insoluble silver sulfide.

The measurement of nanoparticles (NPs) in a biological matrix is essential in various toxicity studies. However, the current knowledge has limitations in differentiating particulate and ionic forms and further identification of their biotransformation. Herein, we evaluate the biotransformation and differential lung clearance kinetics of particulate and ionic forms using PEGylated silver NPs (AgNP-PEGs; 47.51 nm) and PEGylated gold NPs (AuNP-PEGs; 11.76 nm). At 0, 3, and 6 h and 1, 3, 7, and 14 days after a single pharyngeal aspiration in mice at 25 µg/mouse, half of the lung is digested by proteinase K (PK) to separate particulates and ions, and the other half is subjected to the acid digestion method for comparison. The quantitative and qualitative evaluation of lung clearance kinetics suggests that AgNP-PEGs are quickly dissolved and transformed into insoluble silver sulfide (Ag2S), which shows a fast-clearing early phase (0 -6 h; particle T1/2: 4.8 h) and slow-clearing late phase (1 -14 days; particle T1/2: 13.20 days). In contrast, AuNP-PEGs were scarcely cleared or biotransformed in the lungs for 14 days. The lung clearance kinetics of AgNPs and biotransformation shown in this study can be informed by the PK digestion method and cannot be obtained using the acid digestion method.

Antioxidants prevent particulate matter-induced senescence of lung fibroblasts.

Particulate matter (PM) contributes to human diseases, particularly lung disease; however, the molecular mechanism of its action is yet to be determined. Herein, we found that prolonged PM exposure induced the cellular senescence of normal lung fibroblasts via a DNA damage-mediated response. This PM-induced senescence (PM-IS) was only observed in lung fibroblasts but not in A549 lung adenocarcinoma cells. Mechanistic analysis revealed that reactive oxygen species (ROS) activate the DNA damage response signaling axis, increasing p53 phosphorylation, ultimately leading to cellular senescence via an increase in p21 expression without affecting the p16-pRB pathway. A549 cells, instead, were resistant to PM-IS due to the PM-induced ROS production suppression. Water-soluble antioxidants, such as vitamin C and N-Acetyl Cysteine, were found to alleviate PM-IS by suppressing ROS production, implying that antioxidants are a promising therapeutic intervention for PM-mediated lung pathogenesis.

A Simple and Rapid Methicillin-Resistant Staphylococcus aureus (MRSA) Screening Test Using a Mannose-Binding Lectin (MBL)-Conjugated Gold Nanoparticle Probe.

Rapid diagnosis of methicillin-resistant Staphylococcus aureus (MRSA) is essential for guiding clinical treatment and preventing the spread of MRSA infections. Herein, we present a simple and rapid MRSA screening test based on the aggregation effect of mannose-binding lectin (MBL)-conjugated gold nanoparticles (AuNP), called the MRSA probe. Recombinant MBL protein is a member of the lectin family and part of the innate immune system. It can recognize wall teichoic acid (WTA) on the membrane of MRSA more specifically than that of methicillin-sensitive Staphylococcus aureus (MSSA) under optimized salt conditions. Thus, the MRSA probe can selectively bind to MRSA, and the aggregation of the probes on the surface of the target bacteria can be detected and analyzed by the naked eye within 5 min. To demonstrate the suitability of the method for real-world application, we tested 40 clinical S. aureus isolates (including 20 MRSA specimens) and recorded a sensitivity of 100%. In conclusion, the MRSA probe-based screening test with its excellent sensitivity has the potential for successful application in the microbiology laboratory.

Data resource profile: the Korean Community Health Status Indicators (K-CHSI) database.

Korean Community Health Status Indicators (K-CHSI) is a model-based database containing annual data on health outcomes and determinants at the municipal level (si/gun/gu-level regions, including mid-sized cities, counties, and districts). K-CHSI's health outcomes include overall mortality, disease incidence, prevalence rates, and self-reported health. Health determinants were measured in 5 domains: socio-demographic factors, health behaviors, social environment, physical environment, and the healthcare system. The data sources are 71 public databases, including Causes of Death Statistics, Cancer Registration Statistics, Community Health Survey, Population Census, and Census on Establishments and Statistics of Urban Plans. This dataset covers Korea's 17 metropolitan cities and provinces, with data from approximately 250 municipal regions (si/gun/gu). The current version of the database (DB version 1.3) was built using 12 years of data from 2008 to 2019. All data included in K-CHSI may be downloaded via the Korea Community Health Survey site, with no login requirement (https://chs.kdca.go.kr/chs/recsRoom/dataBaseMain.do). K-CHSI covers extensive health outcomes and health determinants at the municipal level over a period of more than 10 years, which enables ecological and time-series analyses of the relationships among various health outcomes and related factors.

Adaptive biosensing platform using immune cell-based nanovesicles for food allergen detection.

Inspired by an adaptive immune system, we have developed a bioelectronic sensing platform which relies on nanovesicles for a signal amplification and can be easily adapted for the detection of new food allergens. In this work, nanovesicles with anti-immunoglobulin E (anti-IgE) antibody receptors were extracted from immune cells and immobilized on a carbon nanotube-based transistor to build a highly sensitive and selective biosensing platform. Our sensor could detect peanut allergen, arachis hypogaea 2 (Ara h 2), down to 0.1 fM and selectively discriminate target allergens in real food samples such as peanut and egg white. As a proof of concept, we demonstrated the detection of different target molecules using the same nanovesicles linked with different antibodies. Our sensor platform was also utilized to quantitatively evaluate the effect of allergy drug such as cromolyn. In this regard, our strategy can be utilized for basic research and versatile applications in food and pharmacological industries.

Low Transcondylar Fractures of the Distal Humerus: A Multicenter Cohort Study.

OBJECTIVES: To determine the demographic characteristics and clinical and radiologic results of low transcondylar fractures and compare them with those of other types of distal humerus fractures using multicenter data and to suggest an optimal method for their treatment. DESIGN: Retrospective cohort study. SETTING: Tertiary-care university hospital. PATIENTS: Between 2009 and 2019, 581 patients who underwent surgery for distal humerus fractures (OTA/AO classification A1 to C3) were enrolled at 7 university-affiliated hospitals. INTERVENTION: Internal fixation of low transcondylar fractures. MAIN OUTCOME MEASURES: Demographic characteristics, including sex, age, mechanism of injury, fixation methods, and complications, were compared between low transcondylar (group A) and other distal humerus (group B) fractures. Clinical outcomes assessed included pain, stability, and range of motion. Radiographs obtained at the latest follow-up were assessed for union, delayed union, nonunion, and implant failure. RESULTS: Mean age was 62.1 ± 19.1 (range, 20-95) years, and it was higher in group A (n = 100) than in group B (n = 376). Patients in group A were predominantly women. Low-energy trauma, such as that from a simple fall, was the most common cause of fracture in group A. Both column fixation, including parallel and orthogonal double plating, was performed more commonly in group A than in group B (87.4% vs. 66.4%, P < 0.001). The nonunion rate was higher in group A, but the difference was not significant. The incidence of ulnar nerve-related symptoms was higher in group A after surgery (6.3% vs. 2.0%, P = 0.003). No significant difference in clinical outcomes was found between the groups. CONCLUSIONS: Low transcondylar fractures occurred more frequently than other distal humerus fractures in older female patients and accounted for 21% of distal humerus fractures. The incidence of ulnar nerve-related symptoms was higher in patients with low transcondylar fractures after surgery. Clinical outcomes were not inferior in patients with low transcondylar fractures. The nonunion rate in patients with low transcondylar fractures treated with double plating was 3.6%. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.