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Background: Congenital sucrase isomaltase deficiency (CSID), an inherited carbohydrate malabsorption disorder, is difficult to diagnose because of overlapping symptoms with other gastrointestinal (GI) diseases. An at-home study was conducted in CSID and healthy adults to evaluate the diagnostic utility of self-reported GI symptoms following administration of a sucrose challenge. Methods: This study investigated the optimum symptom scoring with a sucrose challenge symptoms test (SCST) for diagnosing CSID in 45 confirmed patients and 118 healthy controls. Subjects self-reported the severity of GI symptoms using a 10-point Likert scale after ingesting 50 grams of sucrose on an empty stomach. The receiver operator characteristics curve (ROC) was used to identify the diagnostic variable with the highest Youden Index, a measure of diagnostic performance. Results: All six symptoms were significantly worse in the CSID group within 2 hours after the sucrose challenge. The diagnostic variable with the highest Youden Index was worsening in global symptoms scores at 1- and 2-hours (11.7 [CSID] vs 3.2 [Controls]; P<0.001.) Optimized by gender, the sensitivity and specificity for this diagnostic variable were 87% and 81%, respectively. Conclusions: The SCST is a simple, non-invasive at-home test that can aid in a CSID diagnosis. [ABSTRACT FROM AUTHOR]

Throughout evolution, arboviruses have developed various strategies to counteract the host's innate immune defenses to maintain persistent transmission. Recent studies have shown that, in addition to bacteria and fungi, the innate Toll-Dorsal immune system also plays an essential role in preventing viral infections in invertebrates. However, whether the classical Toll immune pathway is involved in maintaining the homeostatic process to ensure the persistent and propagative transmission of arboviruses in insect vectors remain unclear. In this study, we revealed that the transcription factor Dorsal is actively involved in the antiviral defense of an insect vector (Laodelphax striatellus) by regulating the target gene, zinc finger protein 708 (LsZN708), which mediates downstream immune-related effectors against infection with the plant virus (Rice stripe virus, RSV). In contrast, an antidefense strategy involving the use of the nonstructural-protein (NS4) to antagonize host antiviral defense through competitive binding to Dorsal from the MSK2 kinase was employed by RSV; this competitive binding inhibited Dorsal phosphorylation and reduced the antiviral response of the host insect. Our study revealed the molecular mechanism through which Toll-Dorsal-ZN708 mediates the maintenance of an arbovirus homeostasis in insect vectors. Specifically, ZN708 is a newly documented zinc finger protein targeted by Dorsal that mediates the downstream antiviral response. This study will contribute to our understanding of the successful transmission and spread of arboviruses in plant or invertebrate hosts. [ABSTRACT FROM AUTHOR]

This study introduces a novel method integrating CO2 flooding with radial borehole fracturing for enhanced oil recovery and CO2 underground storage, a solution to the limited vertical stimulation reservoir volume in horizontal well fracturing. A numerical model is established to investigate the production rate, reservoir pressure field, and CO2 saturation distribution corresponding to changing time of CO2 flooding with radial borehole fracturing. A sensitivity analysis on the influence of CO2 injection location, layer spacing, pressure difference, borehole number, and hydraulic fractures on oil production and CO2 storage is conducted. The CO2 flooding process is divided into four stages. Reductions in layer spacing will significantly improve oil production rate and gas storage capacity. However, serious gas channeling can occur when the spacing is lower than 20 m. Increasing the pressure difference between the producer and injector, the borehole number, the hydraulic fracture height, and the fracture width can also increase the oil production rate and gas storage rate. Sensitivity analysis shows that layer spacing and fracture height greatly influence gas storage and oil production. Research outcomes are expected to provide a theoretical basis for the efficient development of shale oil reservoirs in the vertical direction. [ABSTRACT FROM AUTHOR]

Interferon-gamma (IFN-γ) is a major effector molecule of immunity and a common feature of tumors responding to immunotherapy. Active IFN-γ signaling can directly trigger apoptosis and cell cycle arrest in human cancer cells. However, the mechanisms underlying these actions remain unclear. Here, we report that IFN-γ rapidly increases protein synthesis and causes the unfolded protein response (UPR), as evidenced by the increased expression of glucose-regulated protein 78, activating transcription factor-4, and c/EBP homologous protein (CHOP) in cells treated with IFN-γ. The JAK1/2-STAT1 and AKT-mTOR signaling pathways are required for IFN-γ-induced UPR. Endoplasmic reticulum (ER) stress promotes autophagy and restores homeostasis. Surprisingly, in IFN-γ-treated cells, autophagy was impaired at the step of autophagosome-lysosomal fusion and caused by a significant decline in the expression of lysosomal membrane protein-1 and -2 (LAMP-1/LAMP-2). The ER stress inhibitor 4-PBA restored LAMP expression in IFN-γ-treated cells. IFN-γ stimulation activated the protein kinase-like ER kinase (PERK)-eukaryotic initiation factor 2a subunit (eIF2α) axis and caused a reduction in global protein synthesis. The PERK inhibitor, GSK2606414, partially restored global protein synthesis and LAMP expression in cells treated with IFN-γ. We further investigated the functional consequences of IFN-γ-induced ER stress. We show that inhibition of ER stress significantly prevents IFN-γ-triggered apoptosis. CHOP knockdown abrogated IFN-γ-mediated apoptosis. Inhibition of ER stress also restored cyclin D1 expression in IFN-γ-treated cells. Thus, ER stress and the UPR caused by IFN-γ represent novel mechanisms underlying IFN-γ-mediated anticancer effects. This study expands our understanding of IFN-γ-mediated signaling and its cellular actions in tumor cells. [ABSTRACT FROM AUTHOR]

The surface properties of polymer blends are important for many industrial applications. The physical and chemical properties at the surface of polymer blends can be drastically different from those in the bulk due to the surface segregation of the low surface energy component. X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary mass spectrometry (ToF-SIMS) have been widely used to characterize surface and bulk properties. This review provides a brief introduction to the principles of XPS and ToF-SIMS and their application to the study of the surface physical and chemical properties of polymer blends. [ABSTRACT FROM AUTHOR]

This article reviews the recent applications of time-of-flight secondary ion mass spectrometry in the determination of surface structures of semicrystralline and amorphous polymer films. Examples given include the determination of end-group distributions on semicrystalline polymer surfaces, lamellar orientation on thin-film surfaces, the structures of the folds of lamellae, the morphologies of polymer blends, the relationship between film stability and the concentration of the end groups, and the structures of thin polymer films. [ABSTRACT FROM AUTHOR]

Antibody-dependent cell-mediated cytotoxicity plays an important role in the macrophage-mediated destruction of target cells. While the selectivity is based on antibody specificity, the lytic attack is triggered by Fc receptor-mediated respiratory burst. To mimic IgG opsonization, a chimeric antibody-like molecule, containing human IgG1 Fc, was expressed on the surface of mammalian cells. The transmem-brane domain of the human transferrin receptor was fused in-frame to the N-terminus of the second and third domains of human IgG1 heavy-chain constant region. This fusion molecule was designed to take advantage of the type II membrane anchor property of the transferrin receptor to express the Fc portion of the molecule in a reverse orientation, such that the Fc portion projected away from the cell surface. This is in contrast to the conventional cell surface IgG, which is anchored by a C-terminal type I trans-membrane domain. The cell surface expressed reverse Fc no longer activated complement, but retained Fc receptor-binding capability and activated superoxide production by macrophages. This activity was completely blocked by an Fc&gama;R I-specific monoclonal antibody. [ABSTRACT FROM AUTHOR]

Investigates the chemical composition of new bone formed on the alkali-treated titanum surfaces using Time-of-Flight Secondary Ion Mass Spectometry. Examination of the direct bone apposition on the implant surface; Use of SIMS mapping in bone mineralization; Effect of alkali-treated titanum on bone mineralization.