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SIGNIFICANCE: Advances in genetically encoded sensors and two-photon imaging have unlocked functional imaging at the level of single dendritic spines. Synaptic activity can be measured in real time in awake animals. However, tools are needed to facilitate the analysis of the large datasets acquired by the approach. Commonly available software suites for imaging calcium transients in cell bodies are ill-suited for spine imaging as dendritic spines have structural characteristics distinct from those of the cell bodies. We present an automated tuning analysis tool (AUTOTUNE), which provides analysis routines specifically developed for the extraction and analysis of signals from subcellular compartments, including dendritic subregions and spines. AIM: Although the acquisition of in vivo functional synaptic imaging data is increasingly accessible, a hurdle remains in the computation-heavy analyses of the acquired data. The aim of this study is to overcome this barrier by offering a comprehensive software suite with a user-friendly interface for easy access to nonprogrammers. APPROACH: We demonstrate the utility and effectiveness of our software with demo analyses of dendritic imaging data acquired from layer 2/3 pyramidal neurons in mouse V1 in vivo. A user manual and demo datasets are also provided. RESULTS: AUTOTUNE provides a robust workflow for analyzing functional imaging data from neuronal dendrites. Features include source image registration, segmentation of regions-of-interest and detection of structural turnover, fluorescence transient extraction and smoothing, subtraction of signals from putative backpropagating action potentials, and stimulus and behavioral parameter response tuning analyses. CONCLUSIONS: AUTOTUNE is open-source and extendable for diverse functional synaptic imaging experiments. The ease of functional characterization of dendritic spine activity provided by our software can accelerate new functional studies that complement decades of morphological studies of dendrites, and further expand our understanding of neural circuits in health and in disease.

Multiphoton microscopy can resolve fluorescent structures and dynamics deep in scattering tissue and has transformed neural imaging, but applying this technique in vivo can be limited by the mechanical and optical constraints of conventional objectives. Short working distance objectives can collide with compact surgical windows or other instrumentation and preclude imaging. Here we present an ultra-long working distance (20 mm) air objective called the Cousa objective. It is optimized for performance across multiphoton imaging wavelengths, offers a more than 4 mm2 field of view with submicrometer lateral resolution and is compatible with commonly used multiphoton imaging systems. A novel mechanical design, wider than typical microscope objectives, enabled this combination of specifications. We share the full optical prescription, and report performance including in vivo two-photon and three-photon imaging in an array of species and preparations, including nonhuman primates. The Cousa objective can enable a range of experiments in neuroscience and beyond.

The mouse visual cortex contains interconnected higher visual areas, but their functional specializations are unclear. Here, we used a data-driven approach to examine the representations of complex visual stimuli by L2/3 neurons across mouse higher visual areas, measured using large-field-of-view two-photon calcium imaging. Using specialized stimuli, we found higher fidelity representations of texture in area LM, compared to area AL. Complementarily, we found higher fidelity representations of motion in area AL, compared to area LM. We also observed this segregation of information in response to naturalistic videos. Finally, we explored how receptive field models of visual cortical neurons could produce the segregated representations of texture and motion we observed. These selective representations could aid in behaviors such as visually guided navigation.

Imaging the activity of neurons that are widely distributed across brain regions deep in scattering tissue at high speed remains challenging. Here, we introduce an open-source system with Dual Independent Enhanced Scan Engines for Large field-of-view Two-Photon imaging (Diesel2p). Combining optical design, adaptive optics, and temporal multiplexing, the system offers subcellular resolution over a large field-of-view of ~25 mm2, encompassing distances up to 7 mm, with independent scan engines. We demonstrate the flexibility and various use cases of this system for calcium imaging of neurons in the living brain.

BackgroundThe pyrethroid deltamethrin (DM) is broadly used for insect control. Although DM hyperexcites neuronal networks by delaying inactivation of axonal voltage-dependent [Formula: see text] channels, this mechanism is unlikely to mediate neurotoxicity at lower exposure levels during critical perinatal periods in mammals.ObjectivesWe aimed to identify mechanisms by which acute and subchronic DM altered axonal and dendritic growth, patterns of synchronous [Formula: see text] oscillations (SCOs), and electrical spike activity (ESA) functions critical to neuronal network formation.MethodsMeasurements of SCOs using [Formula: see text] imaging, ESA using microelectrode array (MEA) technology, and dendritic complexity using Sholl analysis were performed in primary murine cortical neurons from wild-type (WT) and/or ryanodine receptor 1 ([Formula: see text]) mice between 5 and 14 d in vitro (DIV). [Formula: see text] binding analysis and a single-channel voltage clamp were utilized to measure engagement of RyRs as a direct target of DM.ResultsNeuronal networks responded to DM ([Formula: see text]) as early as 5 DIV, reducing SCO amplitude and depressing ESA and burst frequencies by 60-70%. DM ([Formula: see text]) enhanced axonal growth in a nonmonotonic manner. [Formula: see text] enhanced dendritic complexity. DM stabilized channel open states of RyR1, RyR2, and cortical preparations expressing all three isoforms. DM ([Formula: see text]) altered gating kinetics of RyR1 channels, increasing mean open time, decreasing mean closed time, and thereby enhancing overall open probability. SCO patterns from cortical networks expressing [Formula: see text] were more responsive to DM than WT. [Formula: see text] neurons showed inherently longer axonal lengths than WT neurons and maintained less length-promoting responses to nanomolar DM.ConclusionsOur findings suggested that RyRs were sensitive molecular targets of DM with functional consequences likely relevant for mediating abnormal neuronal network connectivity in vitro. https://doi.org/10.1289/EHP4583.

Mice use vision to navigate and avoid predators in natural environments. However, their visual systems are compact compared to other mammals, and it is unclear how well mice can discriminate ethologically relevant scenes. Here, we examined natural scene discrimination in mice using an automated touch-screen system. We estimated the discrimination difficulty using the computational metric structural similarity (SSIM), and constructed psychometric curves. However, the performance of each mouse was better predicted by the mean performance of other mice than SSIM. This high inter-mouse agreement indicates that mice use common and robust strategies to discriminate natural scenes. We tested several other image metrics to find an alternative to SSIM for predicting discrimination performance. We found that a simple, primary visual cortex (V1)-inspired model predicted mouse performance with fidelity approaching the inter-mouse agreement. The model involved convolving the images with Gabor filters, and its performance varied with the orientation of the Gabor filter. This orientation dependence was driven by the stimuli, rather than an innate biological feature. Together, these results indicate that mice are adept at discriminating natural scenes, and their performance is well predicted by simple models of V1 processing.

Background: Despite advances in treatments for gastric cancer (GC), new targets are needed to enhance treatment, especially when mesenchymal‐epithelial transition (MET) amplification is involved. Therefore, we investigated the genomic features of MET‐amplified GC and efficacy of anti‐MET therapy. Methods: Genomic features were investigated in 2284 patients (cohort 1) and 438 patients in the Cancer Genome Atlas (TCGA cohort). RNA data were obtained from TCGA for expression analysis. Clinical responses of 71 patients (cohort 2) were investigated. Survival rates were compared by Kaplan–Meier and log‐rank tests. Results: In cohort 1, 95 (4.2%) exhibited MET amplifications. In TCGA cohort, 15 (3.4%) exhibited MET amplifications. The five top mutated genes were TP53, CDH1, ARID1A, KMT2D and PIK3CA in cohort 1 and TTN, TP53, MUC16, LRP1B and SYNE1 in TCGA cohort. TP53, PIK3CA, KRAS and GNAS showed significant single nucleotide variants (SNVs) in cohort 1, and TP53 SNVs were significant in TCGA cohort. Fifteen and 18 genes showed significant copy number variations (CNVs) between the MET‐ and non‐MET‐amplified groups in cohort 1 and TCGA cohort, respectively. The PI3K pathway was significantly activated in Chinese patients with MET‐amplified GC (p = 0.002). TP53 expression is negatively associated with MET amplification. Real‐world data obtained with cohort 2 revealed that anti‐MET treatment significantly affected overall survival (OS) (p = 0.002), whereas CNVs did not affect progression‐free or OS even when treatment lines were considered. Conclusions: MET‐amplified GC has a distinctive mutation landscape. Our findings provide valuable information for clinicians who treat patients with MET‐amplified GC. [ABSTRACT FROM AUTHOR]

Background: The clinicopathological features of MET‐amplified gastric cancer (GC) and real‐world data on the efficacy of MET‐targeted therapies remain unknown. Pulmonary lymphangitis carcinomatosis (PLC) is a peculiar manifestation of GC, whose management has not been thoroughly described. Methods: This study analyzed patients diagnosed with MET‐amplified GC or GC with PLC at any time point of the disease course from 2011 to 2021 in two centers. Clinicopathological features and survival outcomes of MET‐amplified GC were analyzed. The clinical and molecular implications of GC with PLC were discussed. Results: Fifty‐eight patients with MET‐amplified GC and 20 patients with GC accompanied by PLC were finally enrolled for analysis (including 13 overlapped patients). GC with PLC was more common in female patients (p = 0.010), diagnosed at a younger age (p = 0.002), presented with a higher baseline ECOG PS (p = 0.016), and was more likely to develop lung metastasis (p < 0.001), and serous effusion (p = 0.026) than GC without PLC. Patients with primary MET‐amplified GC had a worse prognosis than those with secondary MET‐amplified GC (p = 0.005). The application of anti‐MET therapy was associated with numerically prolonged survival, but the association was not statistically significant (p = 0.07). MET amplification was concentrated in patients with PLC, in which anti‐MET therapies elicited a high response rate. Conclusions: MET‐targeted therapies are efficacious in real‐world populations with MET‐amplified GC. Patients with PLC have distinct clinical and molecular features and might benefit from MET‐targeted therapies. [ABSTRACT FROM AUTHOR]

More immune-related adverse events (irAEs) have emerged along with increased immune checkpoint inhibitor (ICI) treatment. ICI-induced myocarditis is a rare type of irAE with early onset, rapid progression, and high mortality. Its specific pathophysiological mechanism is not fully understood. In total, 46 patients with tumors and 16 patients with ICI-induced myocarditis were included. We performed single-cell RNA sequencing on CD3 + T cells, flow cytometry, proteomics, and lipidomics to improve our understanding of the disease. First, we demonstrate the clinical features of patients with PD-1 inhibitor–induced myocarditis. We then identified 18 subsets of T cells using single-cell RNA sequencing and performed comparative analysis and further verification. The composition of T cells in the peripheral blood of patients has changed remarkably. Compared with non-irAE patients, effector T cells were increased in irAE patients, while naive T cells, γδ T cells, and mucosal-associated invariant T cell cluster cells were decreased. Besides, reduced γδ T cells characterized with effector functions, increased natural killer T cells with high levels of FCER1G in patients may suggest an association with disease development. Meanwhile, the peripheral inflammatory response was exacerbated in patients, accompanied by upregulation of exocytosis as well as increased levels of multiple lipids. We provide a comprehensive overview of the composition, gene profiles, and pathway signatures of CD3+ T cells driven by PD-1 inhibitor–induced myocarditis, as well as illustrate clinical features and multi-omic characteristics, providing a unique perspective on disease progression and therapy in clinical practice. We describe the peripheral immune mapping and multi-omics characteristics providing a unique perspective on disease progression and therapy in clinical practice. [ABSTRACT FROM AUTHOR]

Purpose: The prognosis of diffuse‐type gastric cancer (DGC) is poorer than that of intestinal type, but S‐1 is a potential treatment option in DGC. This study explored the maximal tolerated dose (MTD) and the recommended dose for phase II study (RP2D) of nab‐paclitaxel combined with S‐1 (AS regimen) as adjuvant chemotherapy in stage III DGC. Methods: Patients with stage III DGC were recruited into this phase I dose‐escalation study between July 2019 and June 2020 in Zhongshan Hospital. Nab‐paclitaxel and S‐1 (80–120 mg/day, d1‐14, q3w) were administrated for 6 cycles, and then 8 cycles of S‐1 monotherapy were applied. The patients received nab‐paclitaxel at 180, 220, or 260 mg/m2 according to the 3 + 3 design based on dose‐limiting toxicity (DLT). The primary endpoint was RP2D. Secondary endpoints were the 1‐year disease‐free survival (DFS) rate and adverse events (AEs). Results: One case experienced DLT in 180‐mg/m2 dose group, subsequently three additional subjects were enrolled. DLT was not observed in the 220‐ and 260‐mg/m2 dose groups (both n = 3). Therefore, the MTD has not reached, and the RP2D of nab‐paclitaxel would be 260 mg/m2. Five participants showed progressive disease, with three and two participants in the 180‐ and 220‐mg/m2 dose groups, respectively. The 6‐, 12‐, and 18‐month DFS rates were 100%, 63.6%, and 50.9%, respectively. The most frequently observed AEs were neutropenia (83.3%) and leukopenia (66.7%). Conclusion: The RP2D of nab‐paclitaxel as adjuvant chemotherapy in DGC was 260 mg/m2. The AS regimen had a tolerable AE profile in stage III DGC. [ABSTRACT FROM AUTHOR]

Overuse of antibiotics has led to an increased threat of drug-resistant pathogens and sustained chronic infections, suggesting an urgent need for effective strategies against drug-resistant bacterial infections. Herein, we developed au gold nanorods coated with pH-responsive polymers (GNR-DPArPEGMA) for photothermal therapy against multidrug-resistant bacteria. The size and zeta potential of GNR-DPArPEGMA was 78 nm and −37.96 mV, respectively. In subacidic conditions, the nanocomposite surface was positively (14.18 mV) charged, leading to better bacterial adhesion and antibacterial efficiency. The nanocomposites showed augmented in vitro photothermal efficiency up to 70 °C under 808 nm irradiation for 3 min, which further demonstrated an enhanced photothermal bacteria-killing efficiency. The in vivo assays showed that GNR-DPArPEGMA irradiated with near-infrared radiation could treat a drug-resistant Staphylococcus aureus-caused subcutaneous abscess and drug-resistant Pseudomonas aeruginosa-caused pneumonia while reducing the number of bacteria and attenuating inflammation in the infected sites. These results indicate that the nanocomposites could be used as a potential photothermal agent to combat drug-resistant bacterial infections in the future. [ABSTRACT FROM AUTHOR]

Immune checkpoint inhibitors (ICIs) have transformed the treatment in malignancies because of the impact on reactivating the immune cells to kill tumor cells. Because anti-CTLA-4 antibody and anti-PD-1 antibody (or anti-PD-L1 antibody) work in different ways, they have synergistic effects when used in combination in many cancers. However, it has been found that a strong immune response may lead to more serious and multi-system immune-related adverse events (irAE). We describe an advanced esophageal squamous cell carcinoma patient who received nivolumab combined with ipilimumab resulting in hypophysitis and immune-mediated liver injury. He was enrolled into a CheckMate 648 global, multicenter, randomized phase 3 Clinical Trial (CTR20171227) investigating the combined potency of nivolumab and ipilimumab in the treatment of patients with advanced esophageal squamous cell carcinoma and admitted to our center (site 0200). The patient developed hypophysitis and immune-related hepatitis rapidly after ICIs therapy, leading to the interruption of anti-tumor therapy. Then the patient developed Herpes zoster and recurrence of tuberculosis after treatment of irAEs with glucocorticoids. We report this case in the hope that doctors need to have sufficient knowledge and attention to the occurrence of irAE during the anti-immune combination therapy and actively intervene as soon as possible to obtain better anti-tumor effects and less harm to patients. [ABSTRACT FROM AUTHOR]