5-Hydroxytryptamine Enhances the Pacemaker Activity of Interstitial Cells of Cajal in Mouse Colon.

We examined the localization of the 5-hydroxytryptamine (5-HT) receptor and its effects on mouse colonic interstitial cells of Cajal (ICCs) using electrophysiological techniques. Treatment with 5-HT increased the pacemaker activity in colonic ICCs with depolarization of membrane potentials in a dose-dependent manner. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channel blockers blocked pacemaker activity and 5-HT-induced effects. Moreover, an adenylate cyclase inhibitor inhibited 5-HT-induced effects, and cell-permeable 8-bromo-cAMP increased the pacemaker activity. Various agonists of the 5-HT receptor subtype were working in colonic ICCs, including the 5-HT4 receptor. In small intestinal ICCs, 5-HT depolarized the membrane potentials transiently. Adenylate cyclase inhibitors or HCN blockers did not show any influence on 5-HT-induced effects. Anoctamin-1 (ANO1) or T-type Ca2+ channel blockers inhibited the pacemaker activity of colonic ICCs and blocked 5-HT-induced effects. A tyrosine protein kinase inhibitor inhibited pacemaker activity in colonic ICCs under controlled conditions but did not show any influence on 5-HT-induced effects. Among mitogen-activated protein kinase (MAPK) inhibitors, a p38 MAPK inhibitor inhibited 5-HT-induced effects on colonic ICCs. Thus, 5-HT's effect on pacemaker activity in small intestinal and colonic ICCs has excitatory but variable patterns. ANO1, T-type Ca2+, and HCN channels are involved in 5-HT-induced effects, and MAPKs are involved in 5-HT effects in colonic ICCs.

Impact of unmet health-related need on suicidal behavior in Korean adults: a retrospective nationwide cohort study.

We aimed to evaluate the association of unmet health-related need with suicidal behaviors among Korean adults. We included 26,219 adults (13,937 men and 17,788 women) aged ≥ 19 years from the Korea National Health and Nutrition Examination Survey (2015-2020). Suicidal behavior included suicidal plan and attempt. We analyzed the odds ratios and 95% confidence intervals of suicidal behaviors according to unmet health-related need via multivariable logistic regression analysis and performed stratified analyses according to sex, age, income, education, and type of insurance. Of the participants, 9.6% had unmet health-related need. Suicidal plans and attempts had 1.3% and 0.5% of the participants, respectively. The prevalence of suicidal plans and attempts was 0.9% and 0.4% among participants without unmet health-related need and 3.1% and 1.0% among those with such need, respectively. The odd ratios of suicidal plans and attempts increased significantly among participants with unmet health-related need compared to those without. In subgroup analysis, most subgroups showed similar results, except for suicidal plan and attempt in the 45-64 age group, high education, and medical care and suicidal attempt in 19-44 age group, low-income, and unmarried. Unmet health-related need was independently associated with suicidal plan and attempt. A policy alternative is needed for these associations.

Parallel accumulation-serial fragmentation method for in-depth proteomic analysis of bronchoalveolar lavage fluid collected from patients with nonsmall cell lung cancer.

PURPOSE: Advances in mass spectrometry-based quantitative proteomic analysis have successfully demonstrated the in-depth detection of protein biomarkers in bronchoalveolar lavage fluid (BALF) from patients with lung cancers. Recently, ion mobility technology was incorporated into the mass spectrometers escalating the sensitivity and throughput. Utilizing these advantages, herein, we employed the parallel accumulation-serial fragmentation (PASEF) implanted in a timsTOF Pro mass spectrometer to examine the alteration of BALF proteomes in patients with nonsmall cell lung cancers (NSCLCs). EXPERIMENTAL DESIGN: BALF proteins were processed from patients with NSCLC and analyzed in a timsTOF Pro mass spectrometer with the PASEF method using a peptide input of 100 ng. Label-free mass spectrometry data were analyzed in the FragPipe platform. RESULTS: We quantitated over 1400 proteins from a single injection of 100 ng of peptides per sample with a median of ∼2000 proteins. We were able to find a few potential biomarker proteins upregulated in NSCLC. CONCLUSIONS AND CLINICAL RELEVANCE: The alterations of the BALF proteome landscape vary among patients with NSCLC as previously observed in patients with small-cell lung cancers. The PASEF method has significantly enhanced the sensitivity and throughput, demonstrating its effectiveness in clinical research and application.

Development and Validation of a Novel Isotope Dilution-Ultraperformance Liquid Chromatography-Tandem Mass Spectrometry Method for Serum C-Peptide.

Background: Mass spectrometry (MS) methods exhibit higher accuracy and comparability in measuring serum C-peptide concentrations than immunoassays. We developed and validated a novel isotope dilution-ultraperformance liquid chromatography-tandem MS (ID-UPLC-MS/MS) assay to measure serum C-peptide concentrations. Methods: Sample pretreatment involved solid-phase extraction, ion-exchange solid-phase extraction, and derivatization with 6-aminoquinolyl-N-hydroxysuccinimidylcarbamate (Cayman Chemical, Ann Arbor, Michigan, USA). We used an ExionLC UPLC system (Sciex, Framingham, MA, USA) and a Sciex Triple Quad 6500+ MS/MS system (Sciex) for electrospray ionization in positive-ion mode with multiple charge states of [M+3H]3+ and multiple reaction monitoring transitions. The total run time was 50 mins, and the flow rate was 0.20 mL/min. We evaluated the precision, trueness, linearity, lower limit of quantitation (LLOQ), carryover, and matrix effects. Method comparison with electrochemiluminescence immunoassay (ECLIA) was performed in 138 clinical specimens. Results: The intra- and inter-run precision coefficients of variation were <5% and the bias values for trueness were <4%, which were all acceptable. The verified linear interval was 0.050-15 ng/mL, and the LLOQ was 0.050 ng/mL. No significant carryover or matrix effects were observed. The correlation between this ID-UPLC-MS/MS method and ECLIA was good (R=0.995, slope=1.564); however, the ECLIA showed a positive bias (51.8%). Conclusions: The developed ID-UPLC-MS/MS assay shows acceptable performance in measuring serum C-peptide concentrations. This will be useful in situations requiring accurate measurement of serum C-peptide in clinical laboratories.

Laboratory Preparation for Digital Medicine in Healthcare 4.0: An Investigation Into the Awareness and Applications of Big Data and Artificial Intelligence.

Background: Healthcare 4.0. refers to the integration of advanced technologies, such as artificial intelligence (AI) and big data analysis, into the healthcare sector. Recognizing the impact of Healthcare 4.0 technologies in laboratory medicine (LM), we seek to assess the overall awareness and implementation of Healthcare 4.0 among members of the Korean Society for Laboratory Medicine (KSLM). Methods: A web-based survey was conducted using an anonymous questionnaire. The survey comprised 36 questions covering demographic information (seven questions), big data (10 questions), and AI (19 questions). Results: In total, 182 (17.9%) of 1,017 KSLM members participated in the survey. Thirty-two percent of respondents considered AI to be the most important technology in LM in the era of Healthcare 4.0, closely followed by 31% who favored big data. Approximately 80% of respondents were familiar with big data but had not conducted research using it, and 71% were willing to participate in future big data research conducted by the KSLM. Respondents viewed AI as the most valuable tool in molecular genetics within various divisions. More than half of the respondents were open to the notion of using AI as assistance rather than a complete replacement for their roles. Conclusions: This survey highlighted KSLM members' awareness of the potential applications and implications of big data and AI. We emphasize the complexity of AI integration in healthcare, citing technical and ethical challenges leading to diverse opinions on its impact on employment and training. This highlights the need for a holistic approach to adopting new technologies.

The Immune Suppressor IGSF1 as a Potential Target for Cancer Immunotherapy.

The development of first-generation immune-checkpoint inhibitors targeting PD-1/PD-L1 and CTLA-4 ushered in a new era in anticancer therapy. Although immune-checkpoint blockade therapies have shown clinical success, a substantial number of patients yet fail to benefit. Many studies are under way to discover next-generation immunotherapeutic targets. Immunoglobulin superfamily member 1 (IGSF1) is a membrane glycoprotein proposed to regulate thyroid function. Despite containing 12 immunoglobin domains, a possible role for IGSF1, in immune response, remains unknown. Here, our studies revealed that IGSF1 is predominantly expressed in tumors but not normal tissues, and increased expression is observed in PD-L1low non-small cell lung cancer (NSCLC) cells as compared with PD-L1high cells. Subsequently, we developed and characterized an IGSF1-specific human monoclonal antibody, WM-A1, that effectively promoted antitumor immunity and overcame the limitations of first-generation immune-checkpoint inhibitors, likely via a distinct mechanism of action. We further demonstrated high WM-A1 efficacy in humanized peripheral blood mononuclear cells (PBMC), and syngeneic mouse models, finding additive efficacy in combination with an anti-PD-1 (a well-characterized checkpoint inhibitor). These findings support IGSF1 as an immune target that might complement existing cancer immunotherapeutics.