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• As exhibits dose-dependent effects on P. canaliculata growth, with low levels promoting and high levels inhibiting. • Growth inhibition effects are attributed to cytological alterations in the shell and digestive gland. • Up-regulation of genes related to DNA replication and chitosan biosynthesis explains the growth promotion effects. • CYP450, glutathione, arachidonic acid, and ABC transporters involved in As metabolism and transport. Arsenic (As) pollution poses an important problem, but limited information is available about the physiological effects of As on freshwater invertebrates. Here , we investigated the physiological effects of chronic As exposure on Pomacea canaliculata , a freshwater invertebrate. High level of As (Ⅲ, 5 mg/L) inhibited the growth of P. canaliculata , whereas low level of As (Ⅲ, 2 mg/L) promoted growth. Pathological changes in shell and cellular ultrastructure due to As accumulation likely explain the growth inhibition at high As level. Low level of As simulated the expression of genes related to DNA replication and chitosan biosynthesis, potentially accounting for the growth promotion observed. High level of As enrichment pathways primarily involved cytochrome P450, glutathione, and arachidonic acid-mediated metabolism of xenobiotics. ATP-binding cassette (ABC) transporters, specifically the ABCB and ABCC subfamilies, were involved in As transport. Differential metabolites were mainly associated with the metabolism and biosynthesis of amino acids. These findings elucidate the dose-dependent effects of As stress on P. canaliculata growth, with low levels promoting and high levels inhibiting. Additionally, our findings also provide insights into As metabolism and transport in P. canaliculata. [ABSTRACT FROM AUTHOR]

Provides information on a study that determined the threshold condition for initiating the bulk second-order nonlinearity and near-surface second-order nonlinearity in thermally poled Infrasil fued silica glass. Details on the experiment; Results and discussion; Conclusions.

An experimental analysis of the distribution and thickness of the bulk nonlinearity induced in poled silica is reported. The second-order susceptibility decreases exponentially from the anodic interface. Maker fringe patterns showing a double structure are interpreted in relation to the presence of two nonlinear profiles, one concentrated near the anodic surface and another extending into the bulk of the sample. The Maker fringe theory is properly generalized and a double fitting technique reproducing well the experimental results is used to characterize the induced nonlinearities. The dependence of the second-harmonic signal on the poling temperature is given, which is different from that of sol-gel silica. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

It is found that the second-order nonlinearity induced in lead silica by electron-beam irradiation increases linearly with the lead percentage of the glass and a value of 4 pm/V has been estimated for ZF[sub 7] lead silica. The electrostatic field created under the glass surface increases with the lead percentage, which can be explained by the theory of stopping collisions of fast electrons. The layer depth is found proportional to the inverse square root of the lead percentage. The accumulative effect of electron irradiation for inducing the nonlinearity appears limited by the breakdown threshold in the charged layer. An optimum total electron charge per unit of scanned area of 0.29 C/m[sup 2] has been determined for SF[sub 2] glass. Nonlinearity layer depths of 1.9–4.1 μm have been estimated by chemical etching for different lead silica and electron voltages, and the coefficients of the Bohr–Bethe penetration formula have been determined for SF[sub 2] glass. © 1998 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Neoadjuvant chemoradiotherapy (nCRT) has become the standard treatment for patients with locally advanced rectal cancer (LARC). However, 20–40% of patients with LARC show little to no response to nCRT. Thus, comprehensively understanding the tumor microenvironment (TME), which might influence therapeutic efficacy, and identifying robust predictive biomarkers is urgently needed. Pre-treatment tumor biopsy specimens from patients with LARC were evaluated in detail through digital spatial profiling (DSP), public RNA sequencing datasets, and multiplex immunofluorescence (mIF). DSP analysis revealed distinct characteristics of the tumor stroma compared to the normal stroma and tumor compartments. We identified high levels of human leukocyte antigen-DR/major histocompatibility complex class II (HLA-DR/MHC-II) in the tumor compartment and B cells in the stroma as potential spatial predictors of nCRT efficacy in the Discovery cohort. Public datasets validated their predictive capacity for clinical outcomes. Using mIF in an independent nCRT cohort and/or the total cohort, we validated that a high density of HLA-DR/MHC-II+ cells in the tumor and CD20 + B cells in the stroma was associated with nCRT efficacy (all p ≤ 0.021). Spatial profiling successfully characterized the LARC TME and identified robust biomarkers with the potential to accurately predict nCRT response. These findings have important implications for individualized therapy. [Display omitted] • Utilizing DSP, the TME of LARC is characterized. • HLA-DR/MHC-II upregulation in the tumor compartment is significantly associated with improved response to nCRT in LARC. • A high density of B cells in stromal regions predicts nCRT efficacy, strengthening the relevance of B cells in LARC. • HLA-DR genes and B cells are found to be associated with favorable clinical outcomes in LARC public datasets. [ABSTRACT FROM AUTHOR]

Objective To evaluate the feasibility of the supraorbital keyhole approach for suprasellar or intrasuprasellar Rathke cleft cysts (RCCs) under pure endoscopic visualization. Methods Thirteen surgically treated patients with symptomatic RCCs were analyzed retrospectively. Preoperative manifestations included headache (77%), visual impairment (38%), polyuria (31%), and pituitary dysfunction (15%). The maximal cyst diameter averaged 29.3 mm (23−46 mm). Eight patients (62%) had a purely suprasellar lesion, and 5 (38%) had a sellar lesion with suprasellar extension. All patients underwent surgery via supraorbital keyhole approach under pure endoscopic view. The mean duration of follow-up was 21.4 months (9−45 months). Results The cyst content was removed completely in all cases, and the cyst wall was resected partially without transgressing surrounding structures. Preoperative headaches, visual dysfunction, diabetes insipidus, and hypopituitarism resolved in 80%, 60%, 50%, and 50% of patients, respectively. Postoperative complications included transient polyuria in 2 cases and temporary subcutaneous fluid collection in one. No radiological recurrence was observed during the follow-up. Conclusions The supraorbital approach under pure endoscopic visualization provides a valuable optional minimally invasive access for suprasellar and intrasuprasellar RCCs. This approach combines the advantage of minimal invasiveness and improved visualization while avoiding the risk of cerebrospinal fluid leaks, rhinonasal complications, and gland injury. It is particularly suitable for those cysts with the normal pituitary gland occupying the whole or most part of sellar floor. [ABSTRACT FROM AUTHOR]