IFIH1 variants are associated with generalised epilepsy preceded by febrile seizures.

BACKGROUND: IFIH1 variants have been reported to be associated with immune-related disorders with/without seizures. It is unknown whether IFIH1 variants are associated with common epilepsy without acquired causes and the mechanism underlying phenotypic variation remains elusive. METHODS: Trio-based whole-exome sequencing was performed on patients with febrile seizures or epilepsy with antecedent febrile seizures. Previously reported variants were systematically reviewed to investigate genotype-phenotype associations. RESULTS: Two de novo heterozygous and three biallelic missense variants were identified in five patients with generalised epilepsy with antecedent febrile seizures. The variants were predicted to be damaging by in silico tools and were associated with hydrogen bonding changes to neighbouring amino acids or decreased protein stability. Patients exhibited an early onset age and became seizure-free with favourable outcome. Further analysis revealed that de novo missense variants located in the Hel region resulted in seizures with multiple neurological abnormalities, while those in the pincer domain or C-terminal domain led to seizures with normal neurodevelopment, suggesting a sub-molecular effect. Biallelic missense variants, which were inherited from unaffected parents and presented low allele frequencies in general populations, were associated with seizures without neurological abnormalities. Truncation variants were related to refractory epilepsy and severe developmental delay, suggesting a genotype-phenotype correlation. IFIH1 is predominantly expressed in the neonatal stage and decreases dramatically in the adulthood, which is consistent with the early onset age and favourable outcome of the patients. CONCLUSIONS: IFIH1 variants are potentially associated with generalised epilepsy with antecedent febrile seizures. The sub-molecular implication and genotype-phenotype association help explain phenotype variations of IFIH1 variants.

A half sandwich Ru(II)-p-cymene nitrite complex selectively induces cell death in cisplatin-resistant malignant melanoma cells.

The Ru(II)-nitrite complex, Ru4, is explored to release nitric oxide (NO) under acidic conditions and selectively induce a cytotoxic effect towards SK-MEL-28 cisplatin-resistant malignant melanoma cells. These findings suggest that targeting the tumor-associated pHe level could be an effective strategy for the drug function of Ru(II)-nitrite compounds.

Radionuclide therapy of bevacizumab-based PNA-mediated pretargeting.

BACKGROUND: The radionuclide-labeled bevacizumab (BV) is a potential therapeutic approach for vascular endothelial growth factor overexpressed tumors. Because of its large molecular weight, BV is cleared slowly in vivo, which caused damage to healthy tissues and organs. On account of this situation, using the pretargeting strategy with DNA/RNA analogs, such as peptide nucleic acid (PNA), is an effective way of treating solid tumors. METHODS: The BV-PNA conjugate (BV-PNA-1) was injected intravenously as the pretargeted probe, which was specifically accumulated in a solid tumor and gradually metabolically cleared. Then the [177Lu]Lu-labeled complementary PNA strand ([177Lu]Lu-PNA-2) as the second probe was injected, and bound with BV-PNA-1 by the base complementary pairing. In this study, the BV-based PNA-mediated pretargeting strategy was systematically studied, including stability of probes, specific binding ability, biodistribution in animal model, evaluation of single photon emission computed tomography/computed tomography imaging, and therapeutic effect. RESULTS: Compared with group A ([177Lu]Lu-BV), the group B (BV-PNA-1 + [177Lu]Lu-PNA-2) showed lower blood radiotoxicity (22.55 ±1.62 vs. 5.18 ±â€…0.40%, %ID/g, P < 0.05), and similar accumulation of radioactivity in tumor (5.32 ±â€…0.66 vs. 6.68 ± 0.79%, %ID/g, P > 0.05). Correspondingly, there was no significant difference in therapeutic effect between groups A and B. CONCLUSION: The PNA-mediated pretargeting strategy could increase the tumor-to-blood ratio, thereby reducing the damage to normal tissues, while having a similar therapeutic effect to solid tumor. All the experiments in this study showed the potential and effectiveness of pretargeting radioimmunotherapy.

Constructing diagnostic signature of serum microRNAs using machine learning for early pan-cancer detection.

BACKGROUND: Cancer is a major public health concern and the second leading cause of death worldwide. Various studies have reported the use of serum microRNAs (miRNAs) as non-invasive biomarkers for cancer detection. However, large-scale pan-cancer studies based on serum miRNAs have been relatively scarce. METHODS: An optimized machine learning workflow, combining least absolute shrinkage and selection operator (LASSO) analyses, recursive feature elimination (RFE), and fourteen kinds of machine learning algorithms, was use to screen out candidate miRNAs from 2540 serum miRNAs and constructed a potent diagnostic signature (Cancer-related Serum miRNA Signatures) for pan-cancer detection, based on a serum miRNA expression dataset of 38,223 samples. RESULT: Cancer-related Serum miRNA Signatures performed well in pan-cancer detection with an area under curve (AUC) of 0.999, 94.51% sensitivity, and 99.49% specificity in the external validation cohort, and represented an acceptable diagnostic performance for identifying early-stage tumors. Furthermore, the ability of multi-classification of tumors by serum miRNAs in pancreatic, colorectal, and biliary tract cancers was lower than that in other cancers, which showed accuracies of 59%, 58.5%, and 28.9%, respectively, indicating that the difference in serum miRNA expression profiles among a small number of tumor subtypes was not as significant as that between cancer samples and non-cancer controls. CONCLUSION: We have developed a serum miRNA signature using machine learning that may be a cost-effective risk tool for pan-cancer detection. Our findings will benefit not only the predictive diagnosis of cancer but also a preventive and more personalized screening plan.

Hope and its relationship with treatment/ physical related factors in lung cancer patients receiving immunotherapy.

BACKGROUNDPURPOSE: Immunotherapy is a new treatment option for patients with Lung Cancer (LC). However, relatively limited research has explored about patients' perception of hope and its associated factors during the process. This study aimed to examine level of perceived hope and the factors related to hope, with a particular focus on treatment and physically related factors, in LC patients receiving immunotherapy. METHODS: A cross-sectional study was conducted and patients who had already received at least one immunotherapy cycle were recruited from two hospitals in northern Taiwan. The questionnaire included a background information form, the Herth's Hope Index, and the Symptom Severity Scale. Stepwise regression was applied to identify the most robust factors related to level of hope in the participants. RESULTS: A total of 130 patients were recruited. Overall, patients reported moderate to high levels of hope and mild symptoms. Fatigue, weakness, appearance changes, pruritus, and shortness of breath were identified as the most severe symptoms. Further regression analysis showed that patients with poor performance status, less immunotherapy cycles, higher level of fatigue, and more severe pruritus reported to have lower level of hope which explained 47% of the variances. CONCLUSIONS: This study revealed that lung cancer patients undergoing immunotherapy had moderate level of hope. Patients' performance status, selected symptoms and times of receiving immunotherapy were the robust factors related to hope. Systematic assessment of patients' symptoms and the development of appropriate interventions to reduce distress and enhance hope are strongly recommended for both clinical care and research.

Unraveling the association between gut microbiota and chemotherapy efficacy: a two-sample Mendelian randomization study.

Emerging evidence has underscored the complex link between gut microbiota and chemotherapy efficacy; however, establishing causality remains elusive due to confounding factors. This study, leveraging bidirectional two-sample Mendelian randomization (MR) analyses, explores the casual relationship between gut microbiota and chemotherapy efficacy. Utilizing genome-wide association study (GWAS) data from the MiBioGen consortium for gut microbiota and IEU Open GWAS for chemotherapy efficacy, we employed genetic variants as instrumental variables (IVs). The inverse variance weighted (IVW) method, weighted median estimator (WME), and MR-Egger regression method were applied, with sensitivity analyses ensuring robustness. Furthermore, we conducted reverse MR analyses between chemotherapy efficacy and identified significant gut microbial taxa. The results indicated that genus Butyricicoccus (OR = 3.7908, 95% CI: 1.4464-9.9350, P = 0.01), Dorea (OR = 3.3295, 95% CI: 1.2794-8.6643, P = 0.01), Hungatella (OR = 2.6284, 95% CI: 1.0548-6.5498, P = 0.04), and Turicibacter (OR = 2.5694, 95% CI: 1.0392-6.3526, P = 0.04) were positively associated with chemotherapy efficacy using the IVW method. Conversely, family Porphyromonadaceae (OR = 0.2283, 95% CI: 0.0699-0.7461, P = 0.01) and genus Eggerthella (OR = 0.4953, 95% CI: 0.2443-1.0043, P = 0.05) exhibited negative associations. WME demonstrated consistent results with IVW method only for genus Eggerthella (OR = 0.3343, 95% CI: 0.1298-0.8610, P = 0.02). No significant heterogeneity or horizontal pleiotropy was observed. Reverse MR analyses revealed no significant causal effect of chemotherapy on identified gut microbiota. This study sheds light on the intricate relationship between gut microbiota, with a particular emphasis on the genus Eggerthella, and chemotherapy efficacy, offering valuable insights for refining cancer treatment strategies.IMPORTANCEGlobal advancements in cancer treatment, particularly in chemotherapy, have notably decreased mortality rates in recent years. However, the correlation between gut microbiota and chemotherapy efficacy remains elusive. Our study, emphasizing the role of genus Eggerthella, represented a crucial advance in elucidating this intricate interplay. The identified associations offer potential therapeutic targets, contributing to global efforts for enhanced treatment precision and improved patient outcomes. Furthermore, our findings hold promise for personalized therapeutic interventions, shaping improved strategies in the ever-evolving landscape of cancer treatment.

Marine algae-derived characterized bioactive compounds as therapy for cancer: A review on their classification, mechanism of action, and future perspectives.

In 2022, there were around 20 million new cases and over 9.7 million cancer-related deaths worldwide. An increasing number of metabolites with anticancer activity in algae had been isolated and identified, which were promising candidates for cancer therapy. Red algae are well-known for the production of brominated metabolites, including terpenoids and phenols, which have the capacity to induce cell toxicity. Some non-toxic biological macromolecules, including polysaccharides, are distinct secondary metabolites found in many algae, particularly green algae. They possess anticancer activities by inhibiting tumor angiogenesis, stimulating the immune response, and inducing apoptosis. However, the structure-activity relationship between these components and antitumor activity, as well as certain taxa within the algae, remains relatively unstudied. This work is based on the reports published from 2003 to 2024 in PubMed and ISI Web of Science databases. A comprehensive review of the characterized algal anticancer active compounds, together with their structure and mechanism of action was performed. Also, their structure-activity relationship was preliminarily summarized to better assess their potential properties as a natural, safe bioactive product to be used as an alternative for the treatment of cancers, leading to new opportunities for drug discovery.

Spatially Mediated Paper Reactors for On-Site Multicoded Encryption.

This report develops a point-of-use chemical trigger and applies it to a dual-functional chemical encryption chip that enables manual and digital identification with enhanced coding security levels suitable for on-site information verification. The concept relies on conducting continuous chemical synthesis and chromatographic separation of specified compounds on a paper device in a straightforward sketch. In addition to single-step chemical reactions, cascade syntheses and operations involving components of distinct mobilities are also demonstrated. The condensation of dione and hydrazine is first demonstrated on a linear paper reactor, where precursors can mix to react, followed by final product separation under optimized conditions. This linear paper reactor design can also support a multistep cascade Wittig reaction by controlling the relative mobility of reactants, intermediates, and final products. Furthermore, a three-dimensional paper reactor with appropriate mobile phases helps to initiate complex solvent system-driven azide-alkyne cycloaddition. By the use of a three-dimensional device design for spatially limited interdevice reactant transportation, reactants crossing designated boundaries trigger confined chemical reactions at specific positions. Accumulation of repetitive reactions leads to successful product gradient generation and mixing effects, representing a fully controllable intersubstrate chemical operation on the platform. Standing on initiating desired chemical reactions at particular interface regions, integration of appropriate selective reaction area, numerical digits overlay, color diversity, and mobile recognition realizes this dual-functional multicoding encryption process.

Developing an entrustable professional activity for providing health education and consultation in occupational therapy and examining its validity.

BACKGROUND: Entrustable Professional Activities (EPA)-based assessment is easily and intuitively used in evaluating the learning outcomes of competency-based medical education (CBME). This study aimed to develop an EPA for occupational therapy focused on providing health education and consultation (TP-EPA3) and examine its validity. METHODS: Nineteen occupational therapists who had completed online training on the EQual rubric evaluation participated in this study. An expert committee identified six core EPAs for pediatric occupational therapy. TP-EPA3 was developed following the EPA template and refined through consensus meetings. The EQual rubric, a 14-item, five-point criterion-based anchor system, encompassing discrete units of work (DU), entrustable, essential, and important tasks of the profession (EEIT), and curricular role (CR), was used to evaluate the quality of TP-EPA3. Overall scores below 4.07, or scores for DU, EEIT, and CR domains below 4.17. 4.00, and 4.00, respectively, indicate the need for modifications. RESULTS: The TP-EPA3 demonstrated good validity, surpassing the required cut-off score with an average overall EQual score of 4.21 (SD = 0.41). Specific domain scores for DU, EEIT, and CR were 3.90 (SD = 0.69), 4.46 (SD = 0.44), and 4.42 (SD = 0.45), respectively. Subsequent revisions clarified observation contexts, enhancing specificity and focus. Further validation of the revised TP-EPA3 and a thorough examination of its reliability and validity are needed. CONCLUSION: The successful validation of TP-EPA3 suggests its potential as a valid assessment tool in occupational therapy education, offering a structured approach for developing competency in providing health education and consultation. This process model for EPA development and validation can guide occupational therapists in creating tailored EPAs for diverse specialties and settings.

Effects of chain-chain interaction on the configuration of short-chain alkanethiol self-assembled monolayers on a metal surface.

Surface-specific sum frequency generation vibrational spectroscopy is applied to study the molecular configuration of short-chain n-alkanethiol self-assembled monolayers (SAMs with n = 2-6) on the Au surface. For monolayers with n≥ 3, the alkanethiols are upright-oriented, with the CH3 tilt angle varying between ∼33° and ∼46° in clear even-odd dependency. The ethanethiol monolayer (n = 2) is, however, found to exhibit a distinct lying-down configuration with a larger methyl tilt angle (67°-79°) and a smaller CH2 tilt angle (56°-68°). Such a unique configurational transition from n = 2 to n≥ 3 discloses the steric effect owing to chain-chain interaction among neighboring molecules. Through density functional theory calculations, the transition is further confirmed to be energetically favorable for thiols on a defective reconstructed Au(111) surface but not on the pristine one. Our study highlights the roles of the chain-chain interaction and the substrate surface atomic structure when organizing SAMs, offering a strategic pathway for exploiting their applications.

Caveolin-1 differentially regulates the transforming growth factor-ß and epidermal growth factor signaling pathways in MDCK cells.

Caveolin-1 is critical for interacting with the TGF-ß receptor (TGFßR) and EGF receptor (EGFR) signaling, often observed in advanced cancers and tissue fibrosis. However, the mechanism underlying caveolin-1-mediated transactivation of TGFßR and EGFR signaling remains unclear. Therefore, we sought to determine whether caveolin-1 is involved in canonical and non-canonical TGFßR and EGFR signaling transactivation in this study. Methyl-ß-cyclodextrin (MßCD) was used to disrupt the cholesterol-containing membranes domains, and the caveolin-1 scaffolding domain (CSD) peptide was used to mimic the CSD of caveolin-1. Additionally, we transfected the Madin-Darby canine kidney cells with wild-type or phosphorylation-defective caveolin-1. We discovered that tyrosine 14 of caveolin-1 was critical for the negative regulation of TGFßR and EGFR canonical signaling. On the contrary, caveolin-1 inhibited TGF-ß1-induced ERK2 activation independent of tyrosine 14 phosphorylation. Although EGF failed to induce Smad3 phosphorylation in caveolin-1 knockdown cells, it activated Smad3 upon MßCD co-treatment, indicating that caveolin-1 indirectly regulated the non-canonical pathway of EGF. In conclusion, caveolin-1 differentially modulates TGFßR and EGFR signaling. Thus, targeting caveolin-1 is a potential strategy for treating diseases involving TGF-ß1 and EGF signaling.

Heterozygous variants in USP25 cause genetic generalized epilepsy.

USP25 encodes ubiquitin-specific proteases 25, a key member of deubiquitinating enzyme family and is involved in neural fate determination. Although abnormal expression in Down's syndrome was reported previously, the specific role of USP25 in human diseases has not been defined. In this study, we performed trio-based whole exome sequencing in a cohort of 319 cases (families) with generalized epilepsy of unknown etiology. Five heterozygous USP25 variants including two de novo and three co-segregated variants were determined in eight individuals affected by generalized seizures and/or febrile seizures from five unrelated families. The frequency of USP25 variants showed a significantly high aggregation in this cohort compared to the East Asian population and all populations in the gnomAD database. The mean onset ages of febrile and afebrile seizures were 10 months (infancy) and 11.8 years (juvenile), respectively. The patients achieved seizure freedom except one had occasional nocturnal seizures at the last follow-up. Two patients exhibited intellectual disability. Usp25 was ubiquitously expressed in mouse brain with two peaks on embryonic days (E14‒E16) and postnatal day 21, respectively. Similarly, USP25 expressed in fetus/early childhood stage with a second peak at approximately 12‒20 years old in human brain, consistent with the seizure onset age at infancy and juvenile in the patients. To investigate the functional impact of USP25 deficiency in vivo, we established Usp25 knock-out mice, which showed increased seizure susceptibility compared to wild-type mice in pentylenetetrazol-induced seizure test. To explore the impact of USP25 variants, we employed multiple functional detections. In HEK293T cells, the severe phenotype associated variant (p.Gln889Ter) led to a significant reduction of mRNA and protein expressions but formed a stable truncated dimers with increment of deubiquitinating enzyme activities and abnormal cellular aggregations, indicating a gain-of-function effect. The p.Gln889Ter and p.Leu1045del increased neuronal excitability in mice brain, with a higher firing ability in p.Gln889Ter. These functional impairments align with the severity of the observed phenotypes, suggesting a genotype-phenotype correlation. Hence, a moderate association between USP25 and epilepsy was noted, indicating USP25 is potentially a predisposing gene for epilepsy. Our results from Usp25 null mice and the patient-derived variants indicated that USP25 would play epileptogenic role via loss-of-function or gain-of-function effects. The truncated variant p.Gln889Ter would have profoundly different effect on epilepsy. Together, our results underscore the significance of USP25 heterozygous variants in epilepsy, thereby highlighting the critical role of USP25 in the brain.

Impact of glucose-containing fluid on acute pancreatitis outcomes: A multicenter retrospective analysis.

INTRODUCTION: Fluid resuscitation reduces mortality and morbidity in acute pancreatitis (AP); however, whether glucose-containing fluids negatively impact AP remains uncertain. We aimed to examine the association between glucose-containing fluids and AP outcomes. METHODS: This multicenter retrospective cohort study included patients diagnosed with AP between January 2015 and December 2018. Glucose density was defined as total glucose content divided by total fluid volume (g/dl) on day 1, and was considered high if the level exceeded the median. Endpoints were early organ failure (OF), including cardiovascular, renal, or respiratory system failure within 7 days; 30-day OF; ICU admission; and AP-related 90-day mortality. Logistic regression models, restricted cubic spline curves, and Cox proportional hazards models were used for statistical analysis. RESULTS: From the database, 1,146 patients with AP were included. Early OF occurred in 8.8% of patients within 7 days. The high glucose-density group (>5 g/dl) had increased risk of early OF (9.7% vs. 8.2%; adjusted odds ratio [aOR], 1.69; 95% confidence interval [CI], 1.03-2.80; P = 0.039), respiratory failure (8.0% vs. 6.2%; aOR, 1.88; 95% CI, 1.09-3.24; P = 0.024), cardiovascular failure (3.4% vs. 2.4%; aOR, 3.59; 95% CI, 1.28-10.0; P = 0.015), and ICU admission (6.8% vs. 5.8%; aOR, 2.06; 95% CI, 1.08-3.94; P = 0.029), with a dose-response effect observed for cardiovascular failure and ICU admission. A significant increase 30-day OF risk (adjusted hazard ratio [aHR], 1.70; 95% CI, 1.19-2.45) was also noted. CONCLUSION: Excess glucose-containing fluid was associated with increased risks of overall, respiratory, and cardiovascular OF and ICU admission in AP.

Synthesis and Biological Activities of Scleropentaside D.

We report the first total synthesis of scleropentaside D, a unique C-glycosidic ellagitannin, from the ketal derivative of scleropentaside A employing site-selective O4-protection of C-acyl glycoside and copper-catalyzed oxidative coupling reaction of galloyl groups as the key steps. Our study confirms the proposed structure of this natural product, scleropentaside D, and demonstrates its effectiveness as an inhibitor of α-glycosidase.

Diagnosis of neurodegenerative diseases with a refined Lempel-Ziv complexity.

The investigation into the distinctive difference of gait is of significance for the clinical diagnosis of neurodegenerative diseases. However, human gait is affected by many factors like behavior, occupation and so on, and they may confuse the gait differences among Parkinson's disease, amyotrophic lateral sclerosis, and Huntington's disease. For the purpose of examining distinctive gait differences of neurodegenerative diseases, this study extracts various features from both vertical ground reaction force and time intervals. Moreover, refined Lempel-Ziv complexity is proposed considering the detailed distribution of signals based on the median and quartiles. Basic features (mean, coefficient of variance, and the asymmetry index), nonlinear dynamic features (Hurst exponent, correlation dimension, largest Lyapunov exponent), and refined Lempel-Ziv complexity of different neurodegenerative diseases are compared statistically by violin plot and Kruskal-Wallis test to reveal distinction and regularities. The comparative analysis results illustrate the gait differences across these neurodegenerative diseases by basic features and nonlinear dynamic features. Classification results by random forest indicate that the refined Lempel-Ziv complexity can robustly enhance the diagnosis accuracy when combined with basic features.

Morphometric brain organization across the human lifespan reveals increased dispersion linked to cognitive performance.

The human brain is organized as segregation and integration units and follows complex developmental trajectories throughout life. The cortical manifold provides a new means of studying the brain's organization in a multidimensional connectivity gradient space. However, how the brain's morphometric organization changes across the human lifespan remains unclear. Here, leveraging structural magnetic resonance imaging scans from 1,790 healthy individuals aged 8 to 89 years, we investigated age-related global, within- and between-network dispersions to reveal the segregation and integration of brain networks from 3D manifolds based on morphometric similarity network (MSN), combining multiple features conceptualized as a "fingerprint" of an individual's brain. Developmental trajectories of global dispersion unfolded along patterns of molecular brain organization, such as acetylcholine receptor. Communities were increasingly dispersed with age, reflecting more disassortative morphometric similarity profiles within a community. Increasing within-network dispersion of primary motor and association cortices mediated the influence of age on the cognitive flexibility of executive functions. We also found that the secondary sensory cortices were decreasingly dispersed with the rest of the cortices during aging, possibly indicating a shift of secondary sensory cortices across the human lifespan from an extreme to a more central position in 3D manifolds. Together, our results reveal the age-related segregation and integration of MSN from the perspective of a multidimensional gradient space, providing new insights into lifespan changes in multiple morphometric features of the brain, as well as the influence of such changes on cognitive performance.

Modulation of dorsal premotor cortex differentially influences visuomotor adaptation in young and older adults.

The communication between dorsal premotor cortex (PMd) and primary motor cortex (M1) is important for visuomotor adaptation, but it is unclear how this relationship changes with advancing age. The present study recruited 21 young and 23 older participants for two experimental sessions during which intermittent theta burst stimulation (iTBS) or sham was applied over PMd. We assessed the effects of PMd iTBS on M1 excitability using motor evoked potentials (MEP) recorded from right first dorsal interosseous when single-pulse transcranial magnetic stimulation (TMS) was applied with posterior-anterior (PA) or anterior-posterior (AP) currents; and adaptation by quantifying error recorded during a visuomotor adaptation task (VAT). PMd iTBS potentiated PA (P < 0.0001) and AP (P < 0.0001) MEP amplitude in both young and older adults. PMd iTBS increased error in young adults during adaptation (P = 0.026), but had no effect in older adults (P = 0.388). Although PMd iTBS potentiated M1 excitability in both young and older adults, the intervention attenuated visuomotor adaptation specifically in young adults.

Noncanonical mutations in ribosome nascent peptide exit tunnel confer clarithromycin resistance in Mycobacterium abscessus complex.

OBJECTIVES: Mycobacterium abscessus is a non-tuberculous mycobacterial pathogen that causes pulmonary and skin infections globally. Clarithromycin plays a pivotal role in treating M. abscessus infections, with resistance often leading to treatment failure. While canonical mutations in the 23S rRNA residue 2270/2271 are recognized as the primary mechanism for acquired clarithromycin resistance, resistant isolates lacking these mutations have been widely reported. This study aims to identify new mechanisms of clarithromycin resistance in M. abscessus. METHODS: We selected spontaneous resistant mutants derived from two parental strains characterized by erm(41) T28 and C28 sequevars, respectively. Whole-genome sequencing was performed on mutants lacking the 23S rRNA 2270/2271 mutations. Site-directed mutagenesis was used to confirm the resistance phenotypes of newly identified mutations. Bioinformatic analysis of publicly available genomes was conducted to evaluate the presence of these mutations in clinical isolates. The spatial localization of these mutations in the ribosome was analyzed to investigate potential mechanisms of resistance. RESULTS: A total of 135 resistant mutants were selected from the parental strains. Sequencing of the 78 mutants lacking the 23S rRNA 2270/2271 mutations identified mutations within the peptidyl-transferase center and hairpin loops 35, 49, and 74 of the 23S rRNA. These noncanonical mutations were identified in 57 of 1875 genomes of clinical isolates. Thirteen representative mutations were introduced into the bacterial genome, and their contributions to macrolide resistance were confirmed. The newly identified mutations all localized at the entrance of the nascent peptide exit tunnel, potentially contributing to resistance by disrupting the macrolide binding pocket. CONCLUSION: Several noncanonical 23S rRNA mutations conferring clarithromycin resistance were identified. These mutations enhance our understanding of macrolide resistance in M. abscessus and could serve as important markers for diagnosing clarithromycin resistance.

Machine Learning-Enabled Image Classification for Automated Electron Microscopy.

Traditionally, materials discovery has been driven more by evidence and intuition than by systematic design. However, the advent of "big data" and an exponential increase in computational power have reshaped the landscape. Today, we use simulations, artificial intelligence (AI), and machine learning (ML) to predict materials characteristics, which dramatically accelerates the discovery of novel materials. For instance, combinatorial megalibraries, where millions of distinct nanoparticles are created on a single chip, have spurred the need for automated characterization tools. This paper presents an ML model specifically developed to perform real-time binary classification of grayscale high-angle annular dark-field images of nanoparticles sourced from these megalibraries. Given the high costs associated with downstream processing errors, a primary requirement for our model was to minimize false positives while maintaining efficacy on unseen images. We elaborate on the computational challenges and our solutions, including managing memory constraints, optimizing training time, and utilizing Neural Architecture Search tools. The final model outperformed our expectations, achieving over 95% precision and a weighted F-score of more than 90% on our test data set. This paper discusses the development, challenges, and successful outcomes of this significant advancement in the application of AI and ML to materials discovery.