Tumor hypoxia represses γδ T cell-mediated antitumor immunity against brain tumors.

The anatomic location and immunologic characteristics of brain tumors result in strong lymphocyte suppression. Consequently, conventional immunotherapies targeting CD8 T cells are ineffective against brain tumors. Tumor cells escape immunosurveillance by various mechanisms and tumor cell metabolism can affect the metabolic states and functions of tumor-infiltrating lymphocytes. Here, we discovered that brain tumor cells had a particularly high demand for oxygen, which affected γδ T cell-mediated antitumor immune responses but not those of conventional T cells. Specifically, tumor hypoxia activated the γδ T cell protein kinase A pathway at a transcriptional level, resulting in repression of the activatory receptor NKG2D. Alleviating tumor hypoxia reinvigorated NKG2D expression and the antitumor function of γδ T cells. These results reveal a hypoxia-mediated mechanism through which brain tumors and γδ T cells interact and emphasize the importance of γδ T cells for antitumor immunity against brain tumors.

Leucine-Rich Repeat Containing 15-Mediated Cell Adhesion Is Essential for Integrin Signaling in TGF-ß1-Induced PDL Fibroblastic Differentiation.

Human periodontal ligament cells (hPDLCs) cultured from periodontal ligament (PDL) tissue contain postnatal stem cells that can be differentiated into PDL fibroblasts. We obtained PDL fibroblasts from hPDLCs by treatment with low concentrations of TGF-ß1. Since the extracellular matrix and cell surface molecules play an important role in differentiation, we had previously developed a series of monoclonal antibodies against PDL fibroblast-specific cell surface molecules. One of these, the anti-PDL51 antibody, recognized a protein that was significantly upregulated in TGF-ß1-induced PDL fibroblasts and highly accumulated in the PDL region of the tooth root. Mass spectrometry revealed that the antigen recognized by the anti-PDL51 antibody was leucine-rich repeat containing 15 (LRRC15), and this antibody specifically recognized the extracellular glycosylated moiety of LRRC15. Experiments presented here show that as fibroblastic differentiation progresses, increased amounts of LRRC15 localized at the cell surface and membrane. Inhibition of LRRC15 by siRNA-mediated depletion and by antibody blocking resulted in downregulation of the representative PDL fibroblastic markers. Moreover, following LRRC15 inhibition, the directed and elongated cell phenotypes disappeared, and the long processes of the end of the cell body were no longer found. Through a specific interaction between integrin ß1 and LRRC15, the focal adhesion kinase signaling pathway was activated in PDL fibroblasts. Furthermore, it was shown that increased LRRC15 was important for the activation of the integrin-mediated cell adhesion signal pathway for regulation of cellular functions, including fibroblastic differentiation, proliferation, and cell migration arising from the expression of PDL-related genes in TGF-ß1-induced PDL fibroblastic differentiation.

The intracellular Ca2+ channel TRPML3 is a PI3P effector that regulates autophagosome biogenesis.

Autophagy is a multiple fusion event, initiating with autophagosome formation and culminating with fusion with endo-lysosomes in a Ca2+-dependent manner. The source of Ca2+ and the molecular mechanism by which Ca2+ is provided for this process are not known. The intracellular Ca2+ permeable channel transient receptor potential mucolipin 3 (TRPML3) localizes in the autophagosome and interacts with the mammalian autophagy-related protein 8 (ATG8) homolog GATE16. Here, we show that lipid-regulated TRPML3 is the Ca2+ release channel in the phagophore that provides the Ca2+ necessary for autophagy progress. We generated a TRPML3-GCaMP6 fusion protein as a targeted reporter of TRPML3 compartment localization and channel function. Notably, TRPML3-GCaMP6 localized in the phagophores, the level of which increased in response to nutrient starvation. Importantly, phosphatidylinositol-3-phosphate (PI3P), an essential lipid for autophagosome formation, is a selective regulator of TRPML3. TRPML3 interacted with PI3P, which is a direct activator of TRPML3 current and Ca2+ release from the phagophore, to promote and increase autophagy. Inhibition of TRPML3 suppressed autophagy even in the presence of excess PI3P, while activation of TRPML3 reversed the autophagy inhibition caused by blocking PI3P. Moreover, disruption of the TRPML3-PI3P interaction abolished both TRPML3 activation by PI3P and the increase in autophagy. Taken together, these results reveal that TRPML3 is a downstream effector of PI3P and a key regulator of autophagy. Activation of TRPML3 by PI3P is the critical step providing Ca2+ from the phagophore for the fusion process, which is essential for autophagosome biogenesis.

Propulsive colonic contractions are mediated by inhibition-driven poststimulus responses that originate in interstitial cells of Cajal.

The peristaltic reflex is a fundamental behavior of the gastrointestinal (GI) tract in which mucosal stimulation activates propulsive contractions. The reflex occurs by stimulation of intrinsic primary afferent neurons with cell bodies in the myenteric plexus and projections to the lamina propria, distribution of information by interneurons, and activation of muscle motor neurons. The current concept is that excitatory cholinergic motor neurons are activated proximal to and inhibitory neurons are activated distal to the stimulus site. We found that atropine reduced, but did not block, colonic migrating motor complexes (CMMCs) in mouse, monkey, and human colons, suggesting a mechanism other than one activated by cholinergic neurons is involved in the generation/propagation of CMMCs. CMMCs were activated after a period of nerve stimulation in colons of each species, suggesting that the propulsive contractions of CMMCs may be due to the poststimulus excitation that follows inhibitory neural responses. Blocking nitrergic neurotransmission inhibited poststimulus excitation in muscle strips and blocked CMMCs in intact colons. Our data demonstrate that poststimulus excitation is due to increased Ca2+ transients in colonic interstitial cells of Cajal (ICC) following cessation of nitrergic, cyclic guanosine monophosphate (cGMP)-dependent inhibitory responses. The increase in Ca2+ transients after nitrergic responses activates a Ca2+-activated Cl− conductance, encoded by Ano1, in ICC. Antagonists of ANO1 channels inhibit poststimulus depolarizations in colonic muscles and CMMCs in intact colons. The poststimulus excitatory responses in ICC are linked to cGMP-inhibited cyclic adenosine monophosphate (cAMP) phosphodiesterase 3a and cAMP-dependent effects. These data suggest alternative mechanisms for generation and propagation of CMMCs in the colon.

Hydrophobicity Tuning of Cationic Polyaspartamide Derivatives for Enhanced Antisense Oligonucleotide Delivery.

Various cationic polymers are used to deliver polyplex-mediated antisense oligonucleotides (ASOs). However, few studies have investigated the structural determinants of polyplex functionalities in polymers. This study focused on the polymer hydrophobicity. A series of amphiphilic polyaspartamide derivatives possessing various hydrophobic (R) moieties together with cationic diethylenetriamine (DET) moieties in the side chain (PAsp(DET/R)s) were synthesized to optimize the R moieties (or hydrophobicity) for locked nucleic acid (LNA) gapmer ASO delivery. The gene knockdown efficiencies of PAsp(DET/R) polyplexes were plotted against a hydrophobicity parameter, logD7.3, of PAsp(DET/R), revealing that the gene knockdown efficiency was substantially improved by PAsp(DET/R) with logD7.3 higher than -2.4. This was explained by the increased polyplex stability and improved cellular uptake of ASO payloads. After intratracheal administration, the polyplex samples with a higher logD7.3 than -2.4 induced a significantly higher gene knockdown in the lung tissue compared with counterparts with lower hydrophobicity and naked ASO. These results demonstrate that the hydrophobicity of PAsp(DET/R) is crucial for efficient ASO delivery in vitro and in vivo.

Ex Vivo Surface Decoration of Phenylboronic Acid onto Natural Killer Cells for Sialic Acid-Mediated Versatile Cancer Cell Targeting.

Phenylboronic acid (PBA) has been highly acknowledged as a significant cancer recognition moiety in sialic acid-overexpressing cancer cells. In this investigation, lipid-mediated biomaterial integrated PBA molecules onto the surface of natural killer (NK) cells to make a receptor-mediated immune cell therapeutic module. Therefore, a 1,2-distearoyl-sn-glycero-3-phosphorylethanolamine (DSPE) lipid-conjugated di-PEG-PBA (DSPEPEG-di(PEG-PBA) biomaterial was synthesized. The DSPEPEG-di(PEG-PBA) biomaterial exhibited a high affinity for sialic acid (SA), confirmed by fluorescence spectroscopy at pH 6.5 and 7.4. DSPEPEG-di(PEG-PBA) was successfully anchored onto NK cell surfaces (PBA-NK), and this biomaterial maintains intrinsic properties such as viability, ligand availability (FasL & TRAIL), and cytokine secretion response to LPS. The anticancer efficacy of PBA-NK cells was evaluated against 2D cancer cells (MDA-MB-231, HepG2, and HCT-116) and 3D tumor spheroids of MDA-MB-231 cells. PBA-NK cells exhibited greatly enhanced anticancer effects against SA-overexpressing cancer cells. Thus, PBA-NK cells represent a new anticancer strategy for cancer immunotherapy.

Self-Assembled Skin-Penetrating Peptides with Controlled Supramolecular Properties for Enhanced Transdermal Delivery.

The use of nanocarriers decorated with penetration-enhancing agents (PEAs) is considered to be a promising approach for efficient transdermal delivery. In this study, we developed short amphiphilic skin-penetrating peptides (17 amino acids) that functioned not only as PEAs but also as building blocks of nanocarriers without the incorporation of additional macromolecules for self-assembly and guest molecule encapsulation. Interestingly, varying only two amino acids in the hydrophobic moiety of the peptides resulted in significantly different self-assembly behavior, thermal stability, protease resistance, and skin-penetration efficiency in a human skin model. The analysis of the peptide secondary structure revealed that such characteristic changes arose due to the sequence variation-mediated conformational change in the hydrophobic block. These findings hold significant promise for the development of simple and effective delivery systems exhibiting controllable supramolecular properties.

Establishment of canine mammary gland tumor cell lines harboring PI3K/Akt activation as a therapeutic target.

Canine mammary gland tumors (MGT) have a poor prognosis in intact female canines, posing a clinical challenge. This study aimed to establish novel canine mammary cancer cell lines from primary tumors and characterize their cellular and molecular features to find potential therapeutic drugs. The MGT cell lines demonstrated rapid cell proliferation and colony formation in an anchorage-independent manner. Vimentin and α-SMA levels were significantly elevated in MGT cell lines compared to normal canine kidney (MDCK) cells, while CDH1 expression was either significantly lower or not detected at all, based on quantitative real-time PCR (qRT-PCR) analysis. Functional annotation and enrichment analysis revealed that epithelial-mesenchymal transition (EMT) phenotypes and tumor-associated pathways, particularly the PI3K/Akt signaling pathway, were upregulated in MGT cells. BYL719 (Alpelisib), a PI3K inhibitor, was also examined for cytotoxicity on the MGT cell lines. The results show that BYL719 can significantly inhibit the proliferation of MGT cell lines in vitro. Overall, our findings suggest that the MGT cell lines may be valuable for future studies on the development, progression, metastasis, and management of tumors.

Pretreatment Interstitial Lung Abnormalities Detected on Abdominal Computed Tomography Scans in Prostate Cancer Patients.

OBJECTIVE: Prostate cancer and interstitial lung abnormality (ILA) share similar risk factor, which is men and older age. The purpose of this study was to investigate the prevalence of pretreatment ILA among prostate cancer patients who underwent abdominal computed tomography (CT) within 1 year at their first visit to the urology department. In addition, we aimed to assess the association between pretreatment ILA and long-term survival in prostate cancer patients. METHODS: This study was conducted in patients who had a first visit for prostate cancer at urology department between 2005 and 2016 and underwent an abdominal CT within 1 year. A thoracic radiologist evaluated the presence of ILA through inspecting the lung base scanned on an abdominal CT. The association between pretreatment ILA and survival was assessed using Kaplan-Meier analysis with log-rank test. Specific survival rates at 12, 36, and 60 months according to the presence of ILA were evaluated using z -test. Cox regression analysis was used to assess the risk factors of mortality. RESULTS: A total of 173 patients were included (mean age, 70.23 ± 7.98 years). Pretreatment ILA was observed in 10.4% of patients. Patients with ILA were more likely to be older and current smokers. Pretreatment ILA was associated with poor survival ( P < 0.001). Age ≥70 years (hazards ratio [HR], 1.98; 95% confidence interval [CI], 1.24-3.16; P = 0.004), metastatic stage (HR, 2.26; 95% CI, 1.36-3.74; P = 0.002), and ILA (HR, 1.96; 95% CI, 1.06-3.60; P = 0.031) were the independent risk factors of mortality. An ILA (HR, 3.94; 95% CI, 1.78-8.72; P = 0.001) was the only independent risk factor of mortality in localized stage prostate cancer patients. CONCLUSIONS: This study provides important insights into the unexplored effect of pretreatment ILA in prostate cancer patients. Pretreatment ILAs were observed considerably in the lung bases scanned on the abdominal CT scans among prostate cancer patients. Furthermore, pretreatment ILAs were the risk factor of mortality. Therefore, lung bases should be routinely inspected in the abdominal CT scans of prostate cancer patients. This result may help clinicians in establishing personalized management strategy of prostate cancer patients.

Respiratory Viruses Co-detection on a Multiplex RT-PCR Panel: a Comparative Clinical Study.

BACKGROUND: The FilmArray Respiratory Panel RP 2.1 plus (FilmArray RP) is a point-of-care syndromic panel for respiratory pathogens. Although highly valuable in the clinical settings, the co-detection of pathogens in FilmArray RP may confound result interpretation. METHODS: Nasopharyngeal swab specimens collected from patients with respiratory symptoms were analyzed by comparing co-detection results from FilmArray RP with those of Allplex Respiratory Panels (Allplex RP: Power-Chek for SARS-CoV-2). RESULTS: Out of 765 FilmArray RP tests, 143 (18.7%) showed co-detections (two: 122 (85.3%), three: 18 (12.6%), four: 2 (1.4%), and five viruses: 1 (0.7%). The most frequent co-detection was human rhinovirus/enterovirus (HRV/HEV) with respiratory syncytial virus (RSV) (22.3%, 32/143). The overall discordance rate between Film-Array RP and other tests was 32.9%. Notably, discordance in detecting adenovirus (AdV) was significant, with cases detected by FilmArray often not appearing in Allplex RP. CONCLUSIONS: Discordances were varied by virus combination. It is advisable to perform additional confirmatory testing based on clinical relevance.

Association of ambient air pollution with hemoglobin levels and anemia in the general population of Korean adults.

BACKGROUND: Emerging evidence has suggested significant associations between ambient air pollution and changes in hemoglobin levels or anemia in specific vulnerable groups, but few studies have assessed this relationship in the general population. This study aimed to evaluate the association between long-term exposure to air pollution and hemoglobin concentrations or anemia in general adults in South Korea. METHODS: A total of 69,830 Korean adults from a large-scale nationwide survey were selected for our final analysis. Air pollutants included particulate matter with an aerodynamic diameter less than or equal to 10 micrometers (PM10), particulate matter with an aerodynamic diameter less than or equal to 2.5 micrometers, nitrogen dioxide, sulfur dioxide (SO2), and carbon monoxide (CO). We measured the serum hemoglobin concentration to assess anemia for each participant. RESULTS: In the fully adjusted model, exposure levels to PM10, SO2, and CO for one and two years were significantly associated with decreased hemoglobin concentrations (all p < 0.05), with effects ranging from 0.15 to 0.62% per increase in interquartile range (IQR) for each air pollutant. We also showed a significant association of annual exposure to PM10 with anemia (p = 0.0426); the odds ratio (OR) [95% confidence interval (CI)] for anemia per each increase in IQR in PM10 was estimated to be 1.039 (1.001-1.079). This association was also found in the 2-year duration of exposure (OR = 1.046; 95% CI = 1.009-1.083; adjusted Model 2). In addition, CO exposure during two years was closely related to anemia (OR = 1.046; 95% CI = 1.004-1.091; adjusted Model 2). CONCLUSIONS: This study provides the first evidence that long-term exposure to air pollution, especially PM10, is significantly associated with reduced hemoglobin levels and anemia in the general adult population.

Endoscopic findings and predictors of gastrointestinal lesions in children with iron deficiency anemia.

Iron deficiency anemia (IDA) can be caused by occult gastrointestinal (GI) blood loss; however, the endoscopic findings in children with anemia are unclear. The study aimed to determine the frequency and factors related to lesions in children with IDA undergoing endoscopy. We retrospectively analyzed the clinical and endoscopic findings of children with a laboratory-based diagnosis of IDA. Of 58 patients, 36 (62.1%) had upper GI tract lesions, with erosive gastritis being the most common lesion. Further, 26 patients underwent concomitant colonoscopy, and 12 (46.2%) had lower GI tract lesions. Overall, 44 (75.9%) patients had lesions in either the upper or lower GI tract. Helicobacter pylori infection was detected in 13 patients (22.4%). Patients with lesions found by endoscopy had significantly lower hemoglobin level (8.9 vs. 10.0 g/dL, p = 0.047) and mean corpuscular volume (75.5 vs. 80.9 fL, p = 0.038). The proportion of patients with previous treatment for IDA was also higher in those with lesions on endoscopy. In multivariate analysis, age of ≥10 years (odds ratio [OR], 6.00; 95% confidence Interval [CI], 0.56-10.75) and positive fecal occult blood test (FOBT) findings (OR, 2.25; 95% CI, 0.14-4.52) were factors related to GI lesions. The presence of GI symptoms was not associated with GI lesions. A high proportion of GI lesions were found by endoscopy in children with IDA in this study. Endoscopy should be considered in children with IDA even without GI symptoms, especially in older children, and those with positive FOBT results.

Facial Trauma Affects the Radiological Diagnosis of Nasal Bone Fractures.

OBJECTIVES: Timely and accurate diagnosis of nasal bone fractures (NBFs) is crucial for preserving the cosmetic and functional aspects of the nose. This study aims to identify factors influencing radiographic and computed tomography (CT) diagnosis of NBF in patients with nasal trauma. METHODS: Two hundred six patients with acute nasal trauma underwent both conventional radiography and facial bone CT. An experienced otorhinolaryngologist independently interpreted images. Results were categorized into "Concordance" or "Discrepancy" groups, with demographic and clinical data compared. RESULTS: The study classified 167 patients into "Concordance" and 39 into "Discrepancy" groups based on radiography and CT interpretations. The "discrepancy group" showed higher rates of previous nasal bone fractures (P=0.044), rhinoplasty history (P=0.044), and concomitant facial bone fractures (P=0.001). Adjusted odds ratios revealed significant associations between discrepancies and a history of nasal bone fracture (OR=5.197, 95% CI 1.165-23.171), rhinoplasty (OR=6.114, 95% CI 1.393-26.847), and concomitant facial bone fractures (OR=3.765, 95% CI 1.663-8.523). CONCLUSION: This study highlights the impact of facial trauma, including rhinoplasty, on the radiological diagnosis of NBF. Consequently, in the presence of signs of concurrent facial trauma, previous nasal trauma, or rhinoplasty history, a prompt CT scan and comprehensive evaluation are recommended for accurate diagnosis and timely treatment, ultimately improving the patient's prognosis.

Potential Predictors of Severe and Recurrent Pancreatitis in Children: A Single-Center Experience.

OBJECTIVES: Severe pancreatitis often requires intensive care; therefore, early detection is important. This study aimed to evaluate the possible predictors of pancreatitis severity in children. Furthermore, we evaluated the prevalence of pancreatitis recurrence and related factors. METHODS: We retrospectively analyzed the medical records of patients aged younger than 18 years who were diagnosed with acute pancreatitis between January 2017 and June 2022. Acute pancreatitis was diagnosed and classified based on the revised Atlanta criteria. RESULTS: A total of 64 patients were enrolled, and severe pancreatitis was observed in 10 (15.6%) patients. Patients with severe pancreatitis were younger and had higher C-reactive protein levels than those with mild pancreatitis. The areas under the receiver operating characteristic curves of C-reactive protein levels at admission and 48 hours after diagnosis were 0.612 (95% confidence interval, 0.379-0.844) and 0.873 (95% confidence interval, 0.537-0.983), respectively. Fourteen patients (21.9%) experienced further episodes of recurrent pancreatitis. Patients with recurrent pancreatitis were older (13.7 vs 11.4 years, P = 0.022) and prominently boys (85.7 vs 52%, P = 0.022) compared with those without recurrence. Obesity was observed in 4 (0.6%) patients, which was confirmed in all recurrence groups and was statistically significant. CONCLUSIONS: This study demonstrated the feasibility of C-reactive protein in the early risk assessment of patients with acute pancreatitis and highlighted the potential risk of recurrence in patients with obesity.

Eucommia ulmoides Leaves Alleviate Cognitive Dysfunction in Dextran Sulfate Sodium (DSS)-Induced Colitis Mice through Regulating JNK/TLR4 Signaling Pathway.

Ulcerative colitis (UC) is one of the inflammatory bowel diseases (IBD) that is characterized by systemic immune system activation. This study was performed to assess the alleviative effect of administering an aqueous extract of Eucommia ulmoides leaves (AEEL) on cognitive dysfunction in mice with dextran sulfate sodium (DSS)-induced colitis. The major bioactive compounds of AEEL were identified as a quinic acid derivative, caffeic acid-O-hexoside, and 3-O-caffeoylquinic acid using UPLC Q-TOF/MSE. AEEL administration alleviated colitis symptoms, which are bodyweight change and colon shortening. Moreover, AEEL administration protected intestinal barrier integrity by increasing the tight junction protein expression levels in colon tissues. Likewise, AEEL improved behavioral dysfunction in the Y-maze, passive avoidance, and Morris water maze tests. Additionally, AEEL improved short-chain fatty acid (SCFA) content in the feces of DSS-induced mice. In addition, AEEL improved damaged cholinergic systems in brain tissue and damaged mitochondrial and antioxidant functions in colon and brain tissues caused by DSS. Also, AEEL protected against DSS-induced cytotoxicity and inflammation in colon and brain tissues by c-Jun N-terminal kinase (JNK) and the toll-like receptor 4 (TLR4) signaling pathway. Therefore, these results suggest that AEEL is a natural material that alleviates DSS-induced cognitive dysfunction with the modulation of gut-brain interaction.

Transcriptional Changes in Radiation-Induced Lung Injury: A Comparative Analysis of Two Radiation Doses for Preclinical Research.

In a recent stereotactic body radiation therapy animal model, radiation pneumonitis and radiation pulmonary fibrosis were observed at around 2 and 6 weeks, respectively. However, the molecular signature of this model remains unclear. This study aimed to examine the molecular characteristics at these two stages using RNA-seq analysis. Transcriptomic profiling revealed distinct transcriptional patterns for each stage. Inflammatory response and immune cell activation were involved in both stages. Cell cycle processes and response to type II interferons were observed during the inflammation stage. Extracellular matrix organization and immunoglobulin production were noted during the fibrosis stage. To investigate the impact of a 10 Gy difference on fibrosis progression, doses of 45, 55, and 65 Gy were tested. A dose of 65 Gy was selected and compared with 75 Gy. The 65 Gy dose induced inflammation and fibrosis as well as the 75 Gy dose, but with reduced lung damage, fewer inflammatory cells, and decreased collagen deposition, particularly during the inflammation stage. Transcriptomic analysis revealed significant overlap, but differences were observed and clarified in Gene Ontology and KEGG pathway analysis, potentially influenced by changes in interferon-gamma-mediated lipid metabolism. This suggests the suitability of 65 Gy for future preclinical basic and pharmaceutical research connected with radiation-induced lung injury.

Effect of Virtual Game-Based Integrated Clinical Practice Simulation Program on Undergraduate Nursing Students' Attitude Toward Learning.

Game-based virtual reality simulation programs can capitalize on the advantages of non-face-to-face education while effectively stimulating the interest of trainees and improving training efficiency. This study aimed to develop a game-based virtual reality simulation program for nervous system assessment and to evaluate the effects of the program on the learning attitudes of nursing students. Using a one-group pretest-posttest design, 41 senior nursing students were enrolled, and their learning attitudes (self-directed learning attitude, academic self-efficacy, flow-learning experience, and learning presence) were evaluated. The effect of the program was statistically significant in self-directed learning attitude ( t = -2.27, P = .027) and learning presence ( t = -3.07, P = .003), but the difference was not statistically significant in academic self-efficacy ( t = -1.97, P = .054) and learning flow ( t = -0.74, P = .459). The virtual gaming simulation program can be used to effectively replace field training in situations wherein field training is limited, such as during the COVID-19 pandemic.

Differences in patient-reported and clinical characteristics by age group in adults with type 2 diabetes.

BACKGROUND: The global burden of type 2 diabetes (T2D) is growing, and the age of onset is widening, resulting in increasing numbers of young adults and elderly patients with T2D. Age-specific diabetes care needs have yet to be fully explored. AIMS: This study examined (1) differences in patient-reported and clinical characteristics by age group and (2) the effect of age on two proxy measures assessing psychological health and self-care adherence after adjusting for potential mediators. METHODS: A cross-sectional, correlational design was used. Adults with type 2 diabetes (T2D) were recruited from a university hospital in Korea between 2019 and 2020. Participants were divided into four groups based on years of age (40s and younger group [n = 27]; 50s group [n = 47]; 60s group [n = 54]; and 70s and older group [n = 48]) to compare patient-reported and clinical characteristics. Chi-square tests, ANOVA, Kruskal-Wallis tests, and logistic regression analysis were performed to assess group differences and effect of age on psychological health and self-care adherence. RESULTS: Of 178 participants, two-thirds were men (n = 114; 64.41%). The mean ages in the 40s and younger, 50s, 60s, and 70s and older groups were 39.4, 54.7, 63.9, and 76.0 years, respectively. There were significant differences in patient-reported and clinical characteristics by age group. The youngest group reported the poorest psychological health and self-care behaviors. Although the oldest group showed the poorest physical functioning, this group also showed the highest self-care adherence and the best psychological health. Regarding clinical characteristics, traditional diabetes-related blood test results showed no significant group differences. LINKING EVIDENCE TO ACTION: Age-specific diabetes care needs were identified in adults with T2D. Interventions to improve psychological health and priming effects of behavioral adherence need to be developed. Furthermore, meticulous investigation to detect potential complications early is essential in adults with T2D.

Somatodendritic organization of pacemaker activity in midbrain dopamine neurons.

The slow and regular pacemaking activity of midbrain dopamine (DA) neurons requires proper spatial organization of the excitable elements between the soma and dendritic compartments, but the somatodendritic organization is not clear. Here, we show that the dynamic interaction between the soma and multiple proximal dendritic compartments (PDCs) generates the slow pacemaking activity in DA neurons. In multipolar DA neurons, spontaneous action potentials (sAPs) consistently originate from the axon-bearing dendrite. However, when the axon initial segment was disabled, sAPs emerge randomly from various primary PDCs, indicating that multiple PDCs drive pacemaking. Ca2+ measurements and local stimulation/perturbation experiments suggest that the soma serves as a stably-oscillating inertial compartment, while multiple PDCs exhibit stochastic fluctuations and high excitability. Despite the stochastic and excitable nature of PDCs, their activities are balanced by the large centrally-connected inertial soma, resulting in the slow synchronized pacemaking rhythm. Furthermore, our electrophysiological experiments indicate that the soma and PDCs, with distinct characteristics, play different roles in glutamate- induced burst-pause firing patterns. Excitable PDCs mediate excitatory burst responses to glutamate, while the large inertial soma determines inhibitory pause responses to glutamate. Therefore, we could conclude that this somatodendritic organization serves as a common foundation for both pacemaker activity and evoked firing patterns in midbrain DA neurons.

Proximal dendritic localization of NALCN channels underlies tonic and burst firing in nigral dopaminergic neurons.

In multipolar nigral dopamine (DA) neurons, the highly excitable proximal dendritic compartments (PDCs) and two Na+ -permeable leak channels, TRPC3 and NALCN, play a key role in pacemaking. However, the causal link between them is unknown. Here we report that the proximal dendritic localization of NALCN underlies pacemaking and burst firing in DA neurons. Our morphological analysis of nigral DA neurons reveals that TRPC3 is ubiquitously expressed in the whole somatodendritic compartment, but NALCN is localized within the PDCs. Blocking either TRPC3 or NALCN channels abolished pacemaking. However, only blocking NALCN, not TRPC3, degraded burst discharges. Furthermore, local glutamate uncaging readily induced burst discharges within the PDCs, compared with other parts of the neuron, and NALCN channel inhibition dissipated burst generation, indicating the importance of NALCN to the high excitability of PDCs. Therefore, we conclude that PDCs serve as a common base for tonic and burst firing in nigral DA neurons. KEY POINTS: Midbrain dopamine (DA) neurons are slow pacemakers that can generate tonic and burst firings, and the highly excitable proximal dendritic compartments (PDCs) and two Na+ -permeable leak channels, TRPC3 and NALCN, play a key role in pacemaking. We find that slow tonic firing depends on the basal activity of both the NALCN and TRPC3 channels, but that burst firing does not require TRPC3 channels but relies only on NALCN channels. We find that TRPC3 is ubiquitously expressed in the entire somatodendritic compartment, but that NALCN exists only within the PDCs in nigral DA neurons. We show that NALCN channel localization confers high excitability on PDCs and is essential for burst generation in nigral DA neurons. These results suggest that PDCs serve as a common base for tonic and burst firing in nigral DA neurons.