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Objective: Endoscopic submucosal dissection (ESD) in a curative intent for submucosa-invasive early (T1) colorectal cancers (T1-CRCs) often leads to subsequent surgical resection in case of histologic parameters indicating higher risk of nodal involvement. In some cases, however, the expected benefit may be offset by the surgical risks, suggesting a more conservative approach., Design: Retrospective analysis of consecutive patients with T1-CRC who underwent ESD at 13 centres ending inclusion in 2019 (n=3373). Cases with high risk of nodal involvement (non-curative ESD: G3, submucosal invasion>1000 µm, lymphovascular involvement, budding or incomplete resection/R1) were analysed if follow-up data (endoscopy/imaging) were available, regardless of the postendoscopic management (follow-up vs surgery) selected by the multidisciplinary teams in these institutions. Comorbidities were classified according to Charlson Comorbidity Index (CCI). Outcomes were disease recurrence, death and disease-related death rates in the two groups. Rate of residual disease (RD) at both the previous resection site and regional lymph nodes was assessed in the surgical cases as well as from follow-up in the follow-up group., Results: Of 604 patients treated by colorectal ESD for submucosally invasive cancer, 207 non-curative resections (34.3%) were included (138 male; mean age 67.6±10.9 years); in 65.2% of cases, no complete resection was achieved (R1). Of the 207 cases, 60.9% (n=126; median CCI: 3; IQR: 2-4) underwent surgical treatment with RD in 19.8% (25/126), while 39.1% (n=81, median CCI: 5; IQR: 4-6) were followed up by endoscopy in all cases. Patients in the follow-up group had a higher overall mortality (HR=3.95) due to non-CRC causes (n=9, mean survival after ESD 23.7±13.7 months). During this follow-up time, tumour recurrence and disease-specific survival rates were not different between the groups (median follow-up 30 months; range: 6-105)., Conclusion: Following ESD for a lesion at high risk of RD, follow-up only may be a reasonable choice in patients at high risk for surgery. Also, endoscopic resection quality should be improved., Trial Registration Number: NCT03987828., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

The role of transcription factors during astrocyte development and their subsequent effects on neuronal development has been well studied. Less is known about astrocytes contributions towards circuits and behavior in the adult brain. Astrocytes play important roles in synaptic development and modulation, however their contributions towards neuronal sensory function and maintenance of neuronal circuit architecture remain unclear. Here, we show that loss of the transcription factor Sox9 results in both anatomical and functional changes in adult mouse olfactory bulb (OB) astrocytes, affecting sensory processing. Indeed, astrocyte-specific deletion of Sox9 in the OB results in decreased odor detection thresholds and discrimination and it is associated with aberrant neuronal sensory response maps. At functional level, loss of astrocytic Sox9 impairs the electrophysiological properties of mitral and tufted neurons. RNA-sequencing analysis reveals widespread changes in the gene expression profiles of OB astrocytes. In particular, we observe reduced GLT-1 expression and consequential alterations in glutamate transport. Our findings reveal that astrocytes are required for physiological sensory processing and we identify astrocytic Sox9 as an essential transcriptional regulator of mature astrocyte function in the mouse OB., (© 2021. The Author(s).)

Astrocytes are the most abundant glial cell in the central nervous system. They modulate synaptic function through a variety of mechanisms, and yet remain relatively understudied with respect to overall neuronal circuit function. Exploiting the tractability of the mouse olfactory system, we manipulated astrocyte activity and examined how astrocytes modulate olfactory bulb responses. Toward this, we genetically targeted both astrocytes and neurons for in vivo widefield imaging of Ca 2+ responses to odor stimuli. We found that astrocytes exhibited odor response maps that overlap with excitatory neuronal activity. By manipulating Ca 2+ activity in astrocytes using chemical genetics we found that odor-evoked neuronal activity was reciprocally affected, suggesting that astrocyte activation inhibits neuronal odor responses. Subsequently, behavioral experiments revealed that astrocyte manipulations affect both odor detection threshold and discrimination, suggesting that astrocytes play an active role in olfactory sensory processing circuits. Together, these studies show that astrocyte calcium signaling contributes to olfactory behavior through modulation of sensory circuits., (© 2020 Wiley Periodicals, Inc.)

Inhibitory interneurons are integral to sensory processing, yet revealing their cell type-specific roles in sensory circuits remains an ongoing focus. To Investigate the mouse olfactory system, we selectively remove GABAergic transmission from a subset of olfactory bulb interneurons, EPL interneurons (EPL-INs), and assay odor responses from their downstream synaptic partners - tufted cells and mitral cells. Using a combination of in vivo electrophysiological and imaging analyses, we find that inactivating this single node of inhibition leads to differential effects in magnitude, reliability, tuning width, and temporal dynamics between the two principal neurons. Furthermore, tufted and not mitral cell responses to odor mixtures become more linearly predictable without EPL-IN inhibition. Our data suggest that olfactory bulb interneurons, through exerting distinct inhibitory functions onto their different synaptic partners, play a significant role in the processing of odor information.

The mouse olfactory bulb (OB) features continued, activity-dependent integration of adult-born neurons, providing a robust model with which to examine mechanisms of plasticity in the adult brain. We previously reported that local OB interneurons secrete the neuropeptide corticotropin-releasing hormone (CRH) in an activity-dependent manner onto adult-born granule neurons and that local CRH signaling promotes expression of synaptic machinery in the bulb. This effect is mediated via activation of the CRH receptor 1 ( CRHR1 ), which is developmentally regulated during adult-born neuron maturation. CRHR1 is a G S -protein-coupled receptor that activates CREB-dependent transcription in the presence of CRH. Therefore, we hypothesized that locally secreted CRH activates CRHR1 to initiate circuit plasticity programs. To identify such programs, we profiled gene expression changes associated with CRHR1 activity in adult-born neurons of the OB. Here, we show that CRHR1 activity influences expression of the brain-specific Homeobox-containing transcription factor POU Class 6 Homeobox 1 ( POU6f1 ). To elucidate the contributions of POU6f1 toward activity-dependent circuit remodeling, we targeted CRHR1 + neurons in male and female mice for cell-type-specific manipulation of POU6f1 expression. Whereas loss of POU6f1 in CRHR1 + neurons resulted in reduced dendritic complexity and decreased synaptic connectivity, overexpression of POU6f1 in CRHR1 + neurons promoted dendritic outgrowth and branching and influenced synaptic function. Together, these findings suggest that the transcriptional program directed by POU6f1 downstream of local CRH signaling in adult-born neurons influences circuit dynamics in response to activity-dependent peptide signaling in the adult brain. SIGNIFICANCE STATEMENT Elucidating mechanisms of plasticity in the adult brain is helpful for devising strategies to understand and treat neurodegeneration. Circuit plasticity in the adult mouse olfactory bulb is exemplified by both continued cell integration and synaptogenesis. We previously reported that these processes are influenced by local neuropeptide signaling in an activity-dependent manner. Here, we show that local corticotropin-releasing hormone (CRH) signaling induces dynamic gene expression changes in CRH receptor expressing adult-born neurons, including altered expression of the transcription factor POU6f1 We further show that POU6f1 is necessary for proper dendrite specification and patterning, as well as synapse development and function in adult-born neurons. Together, these findings reveal a novel mechanism by which peptide signaling modulates adult brain circuit plasticity., (Copyright © 2018 the authors 0270-6474/18/381444-19$15.00/0.)

Sensory stimulation leads to structural changes within the CNS (Central Nervous System), thus providing the fundamental mechanism for learning and memory. The olfactory circuit offers a unique model for studying experience-dependent plasticity, partly due to a continuous supply of integrating adult born neurons. Our lab has recently implemented an olfactory cued learning paradigm in which specific odor pairs are coupled to either a reward or punishment to study downstream circuit changes. The following protocol outlines the basic set up for our learning paradigm. Here, we describe the equipment setup, programming of software, and method of behavioral training.

Despite the misnomer, Marjolin's ulcers really reflect malignant degeneration arising within a pre-existing cicatrix or scar. In most instances, biopsied lesions demonstrate well-differentiated squamous cell tumors, although other epidermoid lesions are occasionally encountered. The lesions are rare and are most commonly found in the lower extremity, especially the heel and plantar foot. In light of the close association of these lesions with scarred tissues associated with various chronic lower-extremity wounds, those involved in health care delivery to these patients must be aware of Marjolin's ulcer, its manifestations and potential ramifications.

Intra-articular corticosteroid injections are frequently used in the management of both osteoarthritis and rheumatoid arthritis, with most evidence and articles confined to the knee joint. There are few articles that deal with intra-articular corticosteroid injections in the foot and ankle. The aim of this critical literature review is to find the most up-to-date material on intra-articular corticosteroid injections for the foot and ankle. This article will review: effects of corticosteroids; pharmacology of injectable corticosteroids; mechanism of action; indications and contraindications; agents and the dosages; adverse effects; and injection techniques. All Foreign and English language journals were searched. Please refer to Section 2 for search criteria., (Copyright © 2010 Elsevier Ltd. All rights reserved.)