Dynamic genomic changes in methotrexate-resistant human cancer cell lines beyond DHFR amplification suggest potential new targets for preventing drug resistance.

BACKGROUND: Although DHFR gene amplification has long been known as a major mechanism for methotrexate (MTX) resistance in cancer, the early changes and detailed development of the resistance are not yet fully understood. METHODS: We performed genomic, transcriptional and proteomic analyses of human colon cancer cells with sequentially increasing levels of MTX-resistance. RESULTS: The genomic amplification evolved in three phases (pre-amplification, homogenously staining region (HSR) and extrachromosomal DNA (ecDNA)). We confirm that genomic amplification and increased expression of DHFR, with formation of HSRs and especially ecDNAs, is the major driver of resistance. However, DHFR did not play a detectable role in the early phase. In the late phase (ecDNA), increase in FAM151B protein level may also have an important role by decreasing sensitivity to MTX. In addition, although MSH3 and ZFYVE16 may be subject to different posttranscriptional regulations and therefore protein expressions are decreased in ecDNA stages compared to HSR stages, they still play important roles in MTX resistance. CONCLUSION: The study provides a detailed evolutionary trajectory of MTX-resistance and identifies new targets, especially ecDNAs, which could help to prevent drug resistance. It also presents a proof-of-principal approach which could be applied to other cancer drug resistance studies.

Exploring hydrological controls on dissolved organic carbon export dynamics in a typical flash flood catchment using a process-based model.

The dynamics of dissolved organic carbon (DOC) export from headwater catchments are of critical importance for the global carbon balance and are driven by complex runoff processes. Most previous studies have used statistical relationships between runoff and DOC concentration to estimate DOC export dynamics. Thus, the coupling mechanisms between runoff generation and DOC export dynamics at the process level were obscured in the fitting parameters and have rarely been addressed. In this study, high-frequency (hourly) discharge and DOC export from a typical flash flood experimental headwater catchment with an area of 1.8 km2 were simulated using a process-based model (INCA-C). The results showed that the INCA-C model successfully captured the hourly dynamics of both discharge and DOC concentrations with a Nash-Sutcliffe efficiency (NSE) of 0.47-0.81 and 0.28-0.70 among moderate events and 0.81-0.85 and 0.19-0.90 among extreme events, respectively. The DOC was exported with distinct concentration dynamics, fluxes, and contributions from the four flow pathways under different storm intensities. At higher intensities, the DOC fluxes were exported by subsurface flows, particularly from shallow organic soil, with greater peaks and shorter time-to-peaks. Exported DOC is primarily sourced from subsurface runoff from the mineral layer (73 %-77 %) during moderate events, whereas it is primarily sourced from subsurface runoff from the organic layer (61 %-79 %) during extreme events. The two contrasting contributions suggest that hydrological pathway controls and DOC dynamic patterns can shift owing to runoff generation influenced by storm intensity. The distinct and variable controls of different flow pathways on DOC export highlight the need to explain the role of hydrology in regulating DOC storm exports through process-based modelling.

Novel insights into the ecDNA formation mechanism involving MSH3 in methotrexate­resistant human colorectal cancer cells.

Extrachromosomal DNAs (ecDNAs), also known as double minutes (DMs), can induce a fast increase in gene copy numbers and promote the development of cancer, including drug resistance. MutS homolog 3 (MSH3), a key protein in mismatch repair, has been indicated to participate in the regulation of DNA double­strand break (DSB) repair, which has been reported to be associated with the formation of ecDNAs. However, it remains unclear whether MSH3 can influence drug resistance via ecDNAs in cancer. In the present study, high MSH3 expression was observed in methotrexate (MTX)­resistant HT29 cells [DM­ and homogeneously staining region (HSR)­containing cells] compared with parental HT29 cells. Additionally, decreased amounts of ecDNAs, HSRs and amplified genes locating on ecDNAs and HSRs were detected following depletion of MSH3 and this could be reversed by overexpressing MSH3 in DM­containing cells. No corresponding changes were found in HSR­containing cells. The present study further verified the involvement of MSH3­regulated DNA DSB repair pathways in the formation of ecDNAs by detecting the expression of core proteins and pathway activity. Furthermore, expulsion of ecDNAs/HSRs was detected and increased frequencies of micronuclei/nuclear buds with dihydrofolate reductase (DHFR) signals were observed in MSH3­depleted DM­containing cells. Finally, changes in MSH3 expression could affect DHFR amplification­derived DHFR expression and cell sensitivity to MTX, suggesting that MSH3 may influence cancer drug resistance by altering the amount of ecDNAs. In conclusion, the present study revealed a novel mechanism involving MSH3 in the regulation of ecDNAs by DSB repair, which will have clinical value in the treatment of ecDNA­based drug resistance in cancer.

Extremely Strong and Tough Biodegradable Poly(urethane) Elastomers with Unprecedented Crack Tolerance via Hierarchical Hydrogen-Bonding Interactions.

The elastomers with the combination of high strength and high toughness have always been intensively pursued due to their diverse applications. Biomedical applications frequently require elastomers with biodegradability and biocompatibility properties. It remains a great challenge to prepare the biodegradable elastomers with extremely robust mechanical properties for in vivo use. In this report, we present a polyurethane elastomer with unprecedented mechanical properties for the in vivo application as hernia patches, which was obtained by the solvent-free reaction of polycaprolactone (PCL) and isophorone diisocyanate (IPDI) with N,N-bis(2-hydroxyethyl)oxamide (BHO) as the chain extender. Abundant and hierarchical hydrogen-bonding interactions inside the elastomers hinder the crystallization of PCL segments and facilitate the formation of uniformly distributed hard phase microdomains, which miraculously realize the extremely high strength and toughness with the fracture strength of 92.2 MPa and true stress of 1.9 GPa, while maintaining the elongation-at-break of ≈1900% and ultrahigh toughness of 480.2 MJ m-3 with the unprecedented fracture energy of 322.2 kJ m-2 . Hernia patches made from the elastomer via 3D printing technology exhibit outstanding mechanical properties, biocompatibility, and biodegradability. The robust and biodegradable elastomers demonstrate considerable potentials for in vivo applications.

An End-to-End Steel Surface Classification Approach Based on EDCGAN and MobileNet V2.

In the production process of steel products, it is very important to find defects, which can not only reduce the failure rate of industrial production but also can reduce economic losses. All deep learning-based methods need many labeled samples for training. However, in the industrial field, there is a lack of sufficient training samples, especially in steel surface defects. It is almost impossible to collect enough samples that can be used for training. To solve this kind of problem, different from traditional data enhancement methods, this paper constructed a data enhancement model dependent on GAN, using our designed EDCGAN to generate abundant samples that can be used for training. Finally, we mixed different proportions of the generated samples with the original samples and tested them through the MobileNet V2 classification model. The test results showed that if we added the samples generated by EDCGAN to the original samples, the classification results would gradually improve. When the ratio reaches 80%, the overall classification result reaches the highest, achieving an accuracy rate of more than 99%. The experimental process proves the effectiveness of this method and can improve the quality of steel processing.

CXCL12/CXCR4 Axis Drives the Chemotaxis and Differentiation of B Cells in Bullous Pemphigoid.

Bullous pemphigoid (BP) is an autoimmune bullous skin disease characterized by autoantibodies against the hemidesmosomal proteins in the skin and mucous membranes. The efficiency of B-cell‒targeting biologics in BP indicates the important role of B cells in its pathogenesis. However, abnormal B-cell migration and differentiation in BP require further elucidation. We showed that the number of antibody-secreting cells increased in the circulation and skin lesions of patients with BP and was correlated with disease severity. Bulk RNA sequencing of the peripheral B cells identified 171 upregulated and 408 downregulated genes in patients with BP compared with those in healthy controls, among which CXCR4 was significantly upregulated. Notably, CXCR4+ B cells were enriched in BP skin lesions and exhibited antibody-secreting cell characteristics. Correspondingly, an elevated level of CXCL12, the CXCR4 ligand, was detected in the blister fluid and serum of patients with BP, mediating the chemotaxis and accumulation of CXCR4+ B cells to BP skin lesions. Moreover, CXCL12 activated the transcription factor c-Myc, thus promoting B-cell differentiation into antibody-secreting cells and facilitating autoantibody production, which was blocked by CXCR4 inhibitor in vitro. Collectively, our study reveals that the CXCL12/CXCR4 axis plays a pathogenic role in modulating B-cell trafficking and differentiation, thus targeting CXCR4 represents a potential strategy for treating BP and other autoimmune diseases.

Impact of Self-Concept, Self-Imagination, and Self-Efficacy on English Language Learning Outcomes Among Blended Learning Students During COVID-19.

The purpose of the present study was to explore the direct influence of self-concept and self-imagination on English language learning outcomes (ELLO). Furthermore, this study examined the mediating role of self-efficacy in the relationship between self-concept, self-imagination, and ELLO. A survey questionnaire of 21 items was used in this study. We distributed the questionnaire through QR code and collected the data from 2,517 participants who enrolled in blended learning courses at the undergraduate level in Chinese universities. The relationship among the variables was measured through SmartPLS-SEM 3.3.3 (partial least squares structural equation modeling). The outcomes of the present study indicated a direct, positive, and significant connection of self-concept, self-imagination, and self-efficacy with ELLO. Looking at indirect influences, self-concept and self-imagination, positive and significant, influence ELLO through self-efficacy. Thus, self-efficacy was indicated to play a mediating role between self-concept, self-imagination and ELLO. We can conclude that self-concept, self-imagination, and self-efficacy are the main predictors of ELLO in blended learning courses during the pandemic. Additionally, self-concept and self-imagination along with the intervening role of self-efficacy, play a more effective role in improving ELLO. Moreover, this study provided some useful, practical implications, and future research directions.

Two-/Three-Dimensional Perovskite Bilayer Thin Films Post-Treated with Solvent Vapor for High-Performance Perovskite Photovoltaics.

Perovskite photovoltaics (PPVs) using three-dimensional (3D) perovskites incorporated with two-dimensional (2D) perovskites have drawn great concentration in both academic and industrial sectors. Here, we report high performance of PPVs based on the 2D/3D perovskite bilayer thin film post-annealed with solvent vapor. The 2D/3D perovskite bilayer thin film post-annealed with solvent vapor possesses enlarged crystal size and crystallinity and blue-shifted photoluminescence compared to a 3D MAPbI3 thin film. Moreover, compared to the PPVs based on a 3D perovskite thin film, enlarged built-in potential, suppressed charge carrier recombination, boosted charge transport, and reduced charge carrier extraction time are observed from the PPVs based on the 2D/3D perovskite bilayer thin film post-annealed with solvent vapor. As a result, perovskite solar cells exhibit a power conversion efficiency of 22.13% and dramatically enhanced stability, and perovskite photodetectors show a photoresponsivity of 1.38 AW-1, detectivity of 6.52 × 1014 cm Hz1/2 W-1, and linear dynamic range of over 167 dB at room temperature. These results demonstrate that we develop a simple method to approach high-performance PPVs by the 2D/3D perovskite bilayer thin film.

A General Crosslinker Strategy to Realize Intrinsic Frozen Resistance of Hydrogels.

Development and understanding of antifreezing materials are fundamentally and practically important for materials design and delivery. However, almost all of antifreezing materials are either organic/icephobic materials containing no water or hydrophilic hydrogels containing antifreezing additives. Here, a general crosslinking strategy to fabricate a family of EGINA-crosslinked double-network hydrogels with intrinsic, built-in antifreezing and mechanical properties, but without any antifreezing additives is proposed and demonstrated. The resultant hydrogels, despite large structural and compositional variations of hydrophilies, electrolytes, zwitterions, and macromolecules of polymer chains, achieved strong antifreezing and mechanical properties in different environments including solution state, gel state, and hydrogel/solid interfaces. Such general antifreezing property of EGINA-crosslinked hydrogels, regardless network compositions, is likely stemmed from their highly hydrophilic and tightly crosslinked DN structures for inducing strong water-network bindings to prevent ice crystal formation from free waters in hydrogel networks. EGINA-crosslinked hydrogels can also serve as a key component to be fabricated into smart windows with high optical transmittance and supercapacitors with excellent electrochemical stability at subzero temperatures. This work provides a simple, blueprint antifreezing design concept and a family of antifreezing hydrogels for the better understanding of the composite-structure-property relationship of antifreezing materials and the fundamentals of confined water in wet soft materials.

Solid-State Double-Network Hydrogel Redox Electrolytes for High-Performance Flexible Supercapacitors.

Flexible supercapacitors have great potential applications in wearable and portable electronics, but their practical applications were limited due to the low energy density and mechanical flexibility of solid-state electrolytes used for the construction of flexible supercapacitors. In this study, we first report the solid-state double-network (DN) hydrogel electrolytes (HEs) incorporated with Na2MoO4 redox additives. It is found that the solid-state DN HEs with Na2MoO4 redox additives exhibit high electrochemical performance, excellent mechanical properties, and fast self-recovery features. We then demonstrate novel symmetric supercapacitors (SSCs) incorporated with the solid-state Na2MoO4 DN HEs and the active carbon cloths as the electrodes. The SSCs exhibit a specific capacitance of 84 mF/cm2 at a current density of 1 mA/cm2 and an energy density of 70 µWh/cm2 at a power density of 3800 µWh/cm2. Moreover, the SSCs retain approximately 80% capacitance retention after 7000 charge/discharge cycles, which indicates that the SSCs possess excellent flexibility and stability. All of these results demonstrate that the SSCs incorporated with the solid-state Na2MoO4 DN HEs as energy-storage devices have great practical applications in wearable and portable electronics.

A novel role of IL-17A in contributing to the impaired suppressive function of Tregs in psoriasis.

BACKGROUND: Regulatory T cells (Tregs) are crucial in maintaining T cell homeostasis and preventing autoimmune responses. Deficiencies in the suppressive function of Tregs contribute to the pathogenesis of various autoimmune diseases, such as psoriasis. However, whether IL-17A upregulation in psoriatic patients contributes to Treg dysfunction is unknown. OBJECTIVE: To explore the effect and underlying mechanism of IL-17A on the suppressive function of Tregs and to evaluate the restoration of the suppressive function of Tregs in psoriasis during anti-IL-17A (secukinumab) treatment. METHODS: In vitro suppression assays were performed with or without the addition of IL-17A to the coculture system. The release of inhibitory cytokines, including IL-10 and TGF-ß, was assessed by qRT-PCR and flow cytometry. RNA-sequencing was conducted to characterize the cellular responses of Tregs. IL-17A signaling activation was analyzed by flow cytometry and immunofluorescence. Blood samples were collected from three psoriasis patients before and after secukinumab treatment. RESULTS: IL-17A blocked the suppressive function of Tregs, possibly by inhibiting the release of TGF-ß and promoting the production of IFN-γ. Moreover, IL-17A activated the NF-κB signaling pathway in Tregs. Inhibition of the NF-κB pathway blocked IL-17A-induced upregulation of IFN-γ without affecting the secretion of TGF-ß by Tregs. Clinical treatment in psoriasis with secukinumab restored the suppressive function and increased production of TGF-ß in Tregs of psoriasis. CONCLUSION: Our study implies a crucial role of IL-17A in mediating the dysfunction of the Treg suppressive function in psoriasis. Secukinumab, which neutralizes IL-17A signaling, restored the suppressive function of Tregs to exert its antipsoriatic effect.

A retrospective study: Clinicopathological and immunohistochemical analysis of 54 cases of tufted angioma.

BACKGROUND: Tufted angioma is a rare benign lesion with vascular proliferation. AIM: To retrospectively analyze the clinicopathological manifestations and immunohistochemical features of tufted angioma. METHODS: Clinical and histopathological features of tufted angioma (n = 54) were evaluated and analyzed retrospectively in the Department of Dermatology, Xijing Hospital from 2003 to 2014. RESULTS: Clinically, tufted angioma usually presented as erythematous plaques and papules on the head and neck (n = 11), trunk (n = 21) and extremities (n = 22), mainly in children (n = 48), without gender difference (24 males and 30 females). A total of 45 cases showed solitary lesions and nine cases showed multiple lesions. Common symptoms included pain (n = 11), tenderness (n = 7), itching (n = 1), hypertrichosis (n = 7), hyperhidrosis (n = 6) and Kasabach-Merritt phenomenon (n = 1). Histopathologically, typical tufted angioma (n = 37) showed proliferation of endothelial cells in a so-called cannonball pattern, while in the early (n = 4) and regressed (n = 13) stages the tufted appearance was not prominent. The proliferated endothelial cells were diffusely positive for CD31 and Wilms tumor 1, focally positive for D2-40 and Prox1, and negative for Glut-1. LIMITATIONS: Our research was confined to patients of Chinese origin and our sample size was limited. CONCLUSIONS: Tufted angioma is a rare vascular neoplasm with diverse clinical manifestations and unique pathological features. It should be recognized as a vascular tumor with lymphatic differentiation. We emphasize the importance of considering tufted angioma in the differential diagnoses of any congenital or acquired vascular tumor.

Hydroa vacciniforme-like lymphoproliferative disorder: Clinicopathologic study of 41 cases.

BACKGROUND: Hydroa vacciniforme-like lymphoproliferative disorder (HVLLPD) is a rare Epstein-Barr virus (EBV)-related disease that is usually found in East Asians and Latin Americans. OBJECTIVE: To report the characteristics of HVLLPD in Chinese patients. METHODS: Retrospective analysis of patients with HVLLPD from a single institute. RESULTS: A total of 41 patients were enrolled. All patients presented with papulovesicular lesions, mainly distributed on sun-exposed areas, with 26 patients showing systemic symptoms. Follow-up data were available for 20 patients, 16 patients were alive, and 4 patients died. Of the 4 deceased patients, 3 had taken a serum EBV DNA test that showed high viral loads. These 3 patients also received chemotherapy. Histopathology was characterized by dense proliferation of lymphocytes in the dermis. Angiotropism or angiodestruction was found in the majority of patients, whereas prominent cellular polymorphism was noticed in only 4 patients. All patients were positive for CD3, TIA1 cytotoxic granule associated RNA binding protein, and EBV-encoded RNA in situ hybridization. LIMITATIONS: This was a retrospective study. CONCLUSIONS: HVLLPD in Chinese patients showed indolent behavior in the majority of cases, which differed from the characteristics of HVLLPD in Latin Americans. Patients with high serum EBV DNA loads had an increased risk of their disease evolving into aggressive disease. Chemotherapy should not be considered as first-line treatment for most Chinese patients.

Removal of Trace Pharmaceuticals from Water using coagulation and powdered activated carbon as pretreatment to ultrafiltration membrane system.

In this study, the efficacy of water treatment technologies: ultra-filtration (UF), powdered activated carbon (PAC), coagulation (COA) and a combination of these technologies (PAC/UF and COA/UF) to remove target pharmaceuticals (Acetaminophen, Bezafibrate, Caffeine, Carbamazepine, Cotinine, Diclofenac, Gemfibrozil, Ibuprofen, Metoprolol, Naproxen, Sulfadimethoxine, Sulfamethazine, Sulfamethoxazole, Sulfathiazole, Triclosan and Trimethoprim) was investigated. Samples of wastewater from municipal WWTPs were analyzed using direct aqueous injection High Performance Liquid Chromatography with Tandem Quadrupole Mass Spectrometric (LC/MS/MS) detection. On concentration basis, results showed an average removal efficiency of 29%, 50%, and 7%, respectively, for the UF, PAC dosage of 50ppm, and COA dosage of 10ppm. When PAC dosage of 100ppm was used as pretreatment to the combined PAC and UF in-line membrane system, a 90.3% removal efficiency was achieved. The removal efficiency of UF in tandem with COA was 33%, an increase of 4% compared with the single UF treatment. The adsorption effect of PAC combined with the physical separation process of UF revealed the best treatment strategy for removing pharmaceutical contaminant from water.