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Traditionally, fresh S. japonicum flowers (SJF) and S. japonicum flowers buds (SJFB) are dried prior to further processing and use. Here, we investigated the ways in which drying techniques, including sun drying (SD), steam drying (STD), microwave drying (MD), hot air drying (HAD, 40 °C, 60 °C, 80 °C, 100 °C), and freeze drying (FD), alter the flavonoid composition of freshly-harvested SJF and SJFB. The flavonoid content of dried samples was determined by Ultra High Performance Liquid Chromatography-Diode Array Detector (UPLC-DAD). Overall, different drying techniques had significantly different effects on the RU content, ranging from 10.63 % (HAD-80 °C) to 34.13 % (HAD-100 °C) in SJF and from 18.91 % (HAD-100 °C) to 29.16 % (HAD-40 °C) and 30.53 % (SD) in SJFB. To clarify the mechanism by which drying affects the RU content of S. japonicum flowers, we studied the activity of a rutin-hydrolyzing enzyme (RHE) isolated from SJF and SJFB using multiple separation and assay methods. According to the Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) results, the apparent molecular weight of the purified RHE was approximately 38 kDa. According to UPLC-DAD, RHE catalyzes the production of quercetin (QU) from rutin (RU), but not from other flavonoid glycosides. Drying fresh SJF and SJFB at low and high temperatures can inhibit RHE activity and prevent RU hydrolysis. Therefore, subjecting freshly-harvest SJF to HAD-100 °C, and freshly-harvest SJFB to SD or HAD-40 °C, can greatly increase the RU content. In particular, HAD is viable for large-scale application due to its simplicity and industrial feasibility.
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Gallbladder cancer (GBC) is the most common malignant tumor of the biliary system, with poor response to current treatments. Abnormal alternative splicing has been associated with the development of a variety of tumors. Combining the GEO database and GBC mRNA-seq analysis, it is found high expression of the splicing factor polypyrimidine region- binding protein 3 (PTBP3) in GBC. Multi-omics analysis revealed that PTBP3 promoted exon skipping of interleukin-18 (IL-18), resulting in the expression of ΔIL-18, an isoform specifically expressed in tumors. That ΔIL-18 promotes GBC immune escape by down-regulating FBXO38 transcription levels in CD8+T cells to reduce PD-1 ubiquitin-mediated degradation is revealed. Using a HuPBMC mouse model, the role of PTBP3 and ΔIL-18 in promoting GBC growth is confirmed, and showed that an antisense oligonucleotide that blocked ΔIL-18 production displayed anti-tumor activity. Furthermore, that the H3K36me3 promotes exon skipping of IL-18 by recruiting PTBP3 via MRG15 is demonstrated, thereby coupling the processes of IL-18 transcription and alternative splicing. Interestingly, it is also found that the H3K36 methyltransferase SETD2 binds to hnRNPL, thereby interfering with PTBP3 binding to IL-18 pre-mRNA. Overall, this study provides new insights into how aberrant alternative splicing mechanisms affect immune escape, and provides potential new perspectives for improving GBC immunotherapy.
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BACKGROUND: The effect of neoadjuvant chemotherapy (NACT) in gallbladder cancer (GBC) patients remains controversial. The aim of this study was to assess the impact of NACT on overall survival (OS) and cancer specific survival (CSS) in patients with localized or locoregionally advanced GBC, and to explore possible protective predictors for prognosis. METHODS: Data for patients with localized or locoregionally advanced GBC (i.e., categories cTx-cT4, cN0-2, and cM0) from 2004 to 2020 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. Patients in the NACT and non-NACT groups were propensity score matched (PSM) 1:3, and the Kaplan-Meier method and log-rank test were performed to analyze the impact of NACT on OS and CSS. Univariable and multivariable Cox regression models were applied to identify the possible prognostic factors. Subgroup analysis was conducted to identify patients who would benefit from NACT. RESULTS: Of the 2676 cases included, 78 NACT and 234 non-NACT patients remained after PSM. In localized or locoregionally advanced GBC patients, the median OS of the NACT and non-NACT was 31 and 16 months (log-rank P < 0.01), and the median CSS of NACT and non-NACT was 32 and 17 months (log-rank P < 0.01), respectively. Longer median OS (31 vs 17 months, log-rank P < 0.01) and CSS (32 vs 20 months, log-rank P < 0.01) was associated with NACT compared with surgery alone. Multivariable Cox regression analysis showed that NACT, stage, and surgery type were prognostic factors for OS and CSS in GBC patients. Subgroup analysis revealed that the survival hazard ratios (HRs) of NACT vs non-NACT for localized or locoregionally advanced GBC patients were significant in most subgroups. CONCLUSIONS: NACT may provide therapeutic benefits for localized or locoregionally advanced GBC patients, especially for those with advanced stage, node-positive, poorly differentiated or undifferentiated disease. NACT combined with radical surgery was associated with a survival advantage. Therefore, NACT combined with surgery may provide a better treatment option for resectable GBC patients.
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Neoplasias de la Vesícula Biliar , Terapia Neoadyuvante , Puntaje de Propensión , Programa de VERF , Humanos , Neoplasias de la Vesícula Biliar/patología , Neoplasias de la Vesícula Biliar/mortalidad , Neoplasias de la Vesícula Biliar/tratamiento farmacológico , Neoplasias de la Vesícula Biliar/terapia , Femenino , Masculino , Terapia Neoadyuvante/métodos , Terapia Neoadyuvante/estadística & datos numéricos , Persona de Mediana Edad , Pronóstico , Anciano , Quimioterapia Adyuvante/estadística & datos numéricos , Quimioterapia Adyuvante/métodos , Estadificación de Neoplasias , Estimación de Kaplan-MeierRESUMEN
Background: Copper metabolism dysfunction has been found to be associated with the progression of various malignant tumors. The aim of this study is to explore the prognostic value of copper metabolism-related genes (CMRGs) in hepatocellular carcinoma (HCC) and their impact on the immune microenvironment. Methods: We identified differentially expressed CMRGs in cancer and adjacent samples of HCC from The Cancer Genome Atlas (TCGA). Consensus clustering was performed to distinguish subgroups, and TIMER and CIBERSORT were applied to analyze the tumor immune microenvironment (TIME). We used the least absolute shrinkage and selection operator (LASSO) and multivariate Cox regression analysis to establish a prognostic risk model for CMRGs. Gene set enrichment analysis (GSEA) was performed to elucidate potential signaling mechanisms associated with the risk group, as well as to determine and compare the tumor mutation burden (TMB), immune cell infiltration levels, and immune checkpoint of the identified risk groups. Results: Two subgroups with significantly different survival rates were identified, with a better prognosis associated with high immune scores, high abundance of immune-infiltrating cells, and a relatively higher immune status. A prognostic risk model based on five CMRGs was constructed, which showed significant prognostic value. When combined with clinical feature column charts, this model can predict the prognosis of patients with HCC. Functional enrichment analysis showed that the low-risk group was enriched in a large number of metabolic pathways, while the high and low-risk groups exhibited different TMB and differential expression of immune checkpoint genes. The established model was validated in an independent International Cancer Genome Consortium (ICGC) dataset. Conclusions: The results indicate that the expression of CMRGs is associated with the prognosis of HCC and the tumor microenvironment, and can serve as a predictive indicator for evaluating the prognosis of HCC.
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DEC205 (CD205) is one of the major endocytic receptors on dendritic cells and has been widely used as a receptor target in immune therapies. It has been shown that DEC205 can recognize dead cells through keratins in a pH-dependent manner. However, the mechanism underlying the interaction between DEC205 and keratins remains unclear. Here we determine the crystal structures of an N-terminal fragment of human DEC205 (CysRâ¼CTLD3). The structural data show that DEC205 shares similar overall features with the other mannose receptor family members such as the mannose receptor and Endo180, but the individual domains of DEC205 in the crystal structure exhibit distinct structural features that may lead to specific ligand binding properties of the molecule. Among them, CTLD3 of DEC205 adopts a unique fold of CTLD, which may correlate with the binding of keratins. Furthermore, we examine the interaction of DEC205 with keratins by mutagenesis and biochemical assays based on the structural information and identify an XGGGX motif on keratins that can be recognized by DEC205, thereby providing insights into the interaction between DEC205 and keratins. Overall, these findings not only improve the understanding of the diverse ligand specificities of the mannose receptor family members at the molecular level but may also give clues for the interactions of keratins with their binding partners in the corresponding pathways.
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Queratinas , Lectinas Tipo C , Modelos Moleculares , Humanos , Células Dendríticas/metabolismo , Lectinas Tipo C/química , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Ligandos , Receptor de Manosa/química , Mutagénesis , Unión Proteica , Pliegue de Proteína , Estructura Terciaria de Proteína , Dominios y Motivos de Interacción de Proteínas , Cristalografía por Rayos XRESUMEN
BACKGROUND: Helicobacter pylori infections are generally acquired during childhood and affect half of the global population, but its transmission route remains unclear. It is reported that H. pylori can be internalized into Candida, but more evidence is needed for the internalization of H. pylori in human gastrointestinal Candida and vaginal Candida. METHODS: Candida was isolated from vaginal discharge and gastric mucosa biopsies. We PCR-amplified and sequenced H. pylori-specific genes from Candida genomic DNA. Using optical and immunofluorescence microscopy, we identified and observed bacteria-like bodies (BLBs) in Candida isolates and subcultures. Intracellular H. pylori antigen were detected by immunofluorescence using Fluorescein isothiocyanate (FITC)-labeled anti-H. pylori IgG antibodies. Urease activity in H. pylori internalized by Candida was detected by inoculating with urea-based Sabouraud dextrose agar, which changed the agar color from yellow to pink, indicating urease activity. RESULTS: A total of 59 vaginal Candida and two gastric Candida strains were isolated from vaginal discharge and gastric mucosa. Twenty-three isolates were positive for H. pylori 16S rDNA, 12 were positive for cagA and 21 were positive for ureA. The BLBs could be observed in Candida cells, which were positive for H. pylori 16S rDNA, and were viable determined by the LIVE/DEAD BacLight Bacterial Viability kit. Fluorescein isothiocyanate (FITC)-conjugated antibodies could be reacted specifically with H. pylori antigen inside Candida cells by immunofluorescence. Finally, H. pylori-positive Candida remained positive for H. pylori 16S rDNA even after ten subcultures. Urease activity of H. pylori internalized by Candida was positive. CONCLUSION: In the form of BLBs, H. pylori can internalize into gastric Candida and even vaginal Candida, which might have great significance in its transmission and pathogenicity.
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Candidiasis Vulvovaginal , Infecciones por Helicobacter , Helicobacter pylori , Excreción Vaginal , Femenino , Humanos , Ureasa/genética , Infecciones por Helicobacter/microbiología , Fluoresceína-5-Isotiocianato , Agar , Antígenos Bacterianos/genética , Mucosa Gástrica/microbiología , Candida/genética , Biopsia , ADN Ribosómico , Urea , Proteínas Bacterianas/genéticaRESUMEN
Background: ginsenoside Rg5 is a rare ginsenoside with known hypoglycemic effects in diabetic mice. This study aimed to explore the effects of ginsenoside Rg5 on skin wound-healing in the Leprdb/db mutant (db/db) mice (C57BL/KsJ background) model and the underlying mechanisms. Methods: Seven-week-old male C57BL/6J, SLC7A11-knockout (KO), the littermate wild-type (WT), and db/db mice were used for in vivo and ex vivo studies. Results: Ginsenoside Rg5 provided through oral gavage in db/db mice significantly alleviated the abundance of apoptotic cells in the wound areas and facilitated skin wound healing. 50 µM ginsenoside Rg5 treatment nearly doubled the efferocytotic capability of bone marrow-derived dendritic cells (BMDCs) from db/db mice. It also reduced NF-κB p65 and SLC7A11 expression in the wounded areas of db/db mice dose-dependently. Ginsenoside Rg5 physically interacted with SLC7A11 and suppressed the cystine uptake and glutamate secretion of BMDCs from db/db and SLC7A11-WT mice but not in BMDCs from SLC7A11-KO mice. In BMDCs and conventional type 1 dendritic cells (cDC1s), ginsenoside Rg5 reduced their glycose storage and enhanced anaerobic glycolysis. Glycogen phosphorylase inhibitor CP-91149 almost abolished the effect of ginsenoside Rg5 on promoting efferocytosis. Conclusion: ginsenoside Rg5 can suppress the expression of SLC7A11 and inhibit its activity via physical binding. These effects collectively alleviate the negative regulations of SLC7A11 on anaerobic glycolysis, which fuels the efferocytosis of dendritic cells. Therefore, ginsenoside Rg5 has a potential adjuvant therapeutic reagent to support patients with wound-healing problems, such as diabetic foot ulcers.
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BACKGROUND: Three-dimensional visualization preoperative evaluation (3D-VPE) and enhanced recovery after surgery (ERAS) have been suggested to improve outcomes of cancer surgery in patients, yet little is known regarding their clinical benefit in patients with gallbladder cancer (GBC). We hypothesized that the combination of 3D-VPE and ERAS would improve the outcome of patients undergoing surgery for GBC. OBJECTIVE: This study aimed to determine if 3D-VPE and ERAS can improve the outcomes and overall survival in patients with GBC, establishing a novel patient management strategy for GBC. METHODS: A total of 227 patients with GBC were recruited and divided into two groups: those who received traditional treatment between January 2000 and December 2010 (n = 86; the control group) and those who underwent 3D-VPE and ERAS between January 2011 and December 2017 (n = 141). Univariate and multivariate analyses were employed to assess the relationship among disease stages, lymph node invasion, and cell differentiation between the two groups. Cox regression analysis was used to investigate patient survival in these groups. RESULTS: Patients who underwent 3D-VPE and ERAS showed a significantly higher R0 resection rate (67.4% vs. 20.9%, p < 0.001) and dissected lymph node number (26.6 ± 12.6 vs. 16.3 ± 7.6 p < 0.001) compared to the control group. The median survival was 27.4 months, and the 1- and 3-year survival rates were 84.4% and 29.8%, respectively, in patients who received combined management; in the control cohort, the median survival was 12.7 months, and the 1- and 3-year survival rates were 53.5% and 15.1%, respectively. In addition, some postoperative complications and risk factors were diminished relative to the traditionally treated patients. CONCLUSION: The implementation of 3D-VPE and ERAS can significantly improve the prognosis and outcomes of patients with GBC and should be considered for wide use in clinical practice.
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Rad18 interacts with the SMC5/6 localization factor 1 (SLF1) to recruit the SMC5/6 complex to DNA damage sites for repair. The mechanism of the specific Rad18 recognition by SLF1 is unclear. Here, we present the crystal structure of the tandem BRCT repeat (tBRCT) in SLF1 (SLF1tBRCT) bound with the interacting Rad18 peptide. Our structure and biochemical studies demonstrate that SLF1tBRCT interacts with two phosphoserines and adjacent residues in Rad18 for high-affinity and specificity Rad18 recognition. We found that SLF1tBRCT utilizes mechanisms common among tBRCTs as well as unique ones for Rad18 binding, the latter include interactions with an α-helical structure in Rad18 that has not been observed in other tBRCT-bound ligand proteins. Our work provides structural insights into Rad18 targeting by SLF1 and expands the understanding of BRCT-mediated complex assembly.
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Daño del ADN , Ubiquitina-Proteína Ligasas , Unión Proteica , Dominios Proteicos , Péptidos , Reparación del ADNRESUMEN
Tribocorrosion is one of the most common forms of failure of biomedical titanium alloys. As the passive film of titanium alloys is highly dependent on oxygen conditions, the passivation behavior and the microstructure of the passive film of Ti-6Al-4V under tribocorrosion in 1 M HCl with a low dissolved oxygen concentration (DOC) were studied by means of electron probe microanalysis (EPMA), Ar-ion etched X-ray photoelectron spectroscopy (XPS), focused ion beam (FIB) milling and high resolution transmission electron microscopy (HRTEM). The results showed that the protective ability of the regenerated passive film decreased sharply under low DOC. Al and V ions dissolved in excess, and a large number of oxygen atoms entered the matrix, leading to internal oxidation. Structural characterization indicated that Ti atoms occupied more metal lattice points in the regenerated passive film and that the high dislocation density in the deformed layer caused by wear facilitated the diffusion of Al and V. Finally, the first-principles calculation showed that Al had the minimum vacancy formation energy.
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BACKGROUND: Ferroptosis plays an important part in Acute lung injury (ALI) caused by sepsis. The six-transmembrane epithelial antigen of the prostate 1 (STEAP1) has potential effects on iron metabolism and inflammation but reports on its function in ferroptosis and sepsis-caused ALI are lacking. Here we explored the role of STEAP1 in sepsis-caused ALI and the possible mechanisms. METHODS AND RESULTS: Lipopolysaccharide (LPS) was added to human pulmonary microvascular endothelial cells (HPMECs) to form the sepsis-caused ALI model in vitro. The Cecal ligation and puncture (CLP) experiment was performed on C57/B6J mice to form the sepsis-caused ALI model in vivo. The effect of STEAP1 on inflammation was investigated by PCR, ELISA, and Western blot for the inflammatory factors and adhesion molecular. The reactive oxygen species (ROS) levels were detected by immunofluorescence. The effect of STEAP1 on ferroptosis was investigated by detecting malondialdehyde (MDA) levels, glutathione (GSH) levels, Fe2+ levels, cell viability, and mitochondrial morphology. Our findings suggested that STEAP1 expression was increased in the sepsis-induced ALI models. Inhibition of STEAP1 decreased the inflammatory response and ROS production as well as MDA levels but increased the levels of Nrf2 and GSH. Meanwhile, inhibition of STEAP1 improved cell viability and restored mitochondrial morphology. Western Blot results showed that inhibition of STEAP1 could affect the SLC7A11/GPX4 axis. CONCLUSION: Inhibition of STEAP1 may be valuable for pulmonary endothelial protection in lung injury caused by sepsis.
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Lesión Pulmonar Aguda , Ferroptosis , Sepsis , Animales , Humanos , Ratones , Lesión Pulmonar Aguda/metabolismo , Antígenos de Neoplasias , Células Endoteliales/metabolismo , Lipopolisacáridos/farmacología , Oxidorreductasas/metabolismo , Próstata/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Sepsis/complicaciones , Sepsis/metabolismoRESUMEN
Scrap steel is a kind of resource that can be recycled indefinitely. However, the enrichment of arsenic in the recycling process will seriously affect the performance of the product, making the recycling process unsustainable. In this study, the removal of arsenic from molten steel using calcium alloys was investigated experimentally, and the underlying mechanism was explored based on thermodynamic principles. The results show that the addition of calcium alloy is an effective means of reducing the arsenic content in molten steel, with the highest removal percentage of 56.36% observed with calcium aluminum alloy. A thermodynamic analysis revealed that the critical calcium content required for arsenic removal reaction is 0.0037%. Moreover, ultra-low levels of oxygen and sulfur were found to be crucial in achieving a good arsenic removal effect. When the arsenic removal reaction occurs in molten steel, the oxygen and sulfur concentrations in equilibrium with calcium were wO=0.0012% and wS=0.00548%, respectively. After successful arsenic removal, the arsenic removal product of the calcium alloy is Ca3As2, which usually does not appear alone. Instead, it is prone to combining with alumina, calcium oxide, and other inclusions to form composite inclusions, which is beneficial for the floating removal of inclusions and the purification of scrap steel in molten steel.
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Ischemia-reperfusion injury (IRI) is one of the most common complications in liver transplantation. METTL3 regulates inflammation and cellular stress response by modulating RNA m6A modification level. Here, the study aimed to investigate the role and mechanism of METTL3 in IRI after rat orthotopic liver transplantation. The total RNA m6A modification and METTL3 expression level was consistently down-regulated after 6â¯h or 24â¯h reperfusion in OLT, which is negatively associated with the hepatic cell apoptosis. Functionally, METTL3 pretreatment in donor significantly inhibited liver grafts apoptosis, improved liver function and depressed the proinflammatory cytokine/chemokine expression. Mechanistically, METTL3 inhibited apoptosis of grafts via upregulating HO-1. Moreover, m6A dot blot and MeRIP-qPCR assay revealed that METTL3 promoted HO-1 expression in an m6A-dependent manner. In vitro, METTL3 alleviated hepatocytes apoptosis by upregulating HO-1 under hypoxia/reoxygenation condition. Taken together, these findings demonstrate that METTL3 ameliorates rat OLT-stressed IRI by inducing HO-1 in an m6A-dependent manner, highlighting a potential target for IRI in liver transplantation.
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Trasplante de Hígado , Daño por Reperfusión , Ratas , Animales , Trasplante de Hígado/efectos adversos , Hígado/metabolismo , Inflamación/metabolismo , Daño por Reperfusión/genética , Daño por Reperfusión/metabolismo , ARN/metabolismoRESUMEN
The mono-ubiquitination of the histone protein H2B (H2Bub1) is a highly conserved histone post-translational modification that plays critical roles in many fundamental processes. In yeast, this modification is catalyzed by the conserved Bre1-Rad6 complex. Bre1 contains a unique N-terminal Rad6-binding domain (RBD), how it interacts with Rad6 and contributes to the H2Bub1 catalysis is unclear. Here, we present crystal structure of the Bre1 RBD-Rad6 complex and structure-guided functional studies. Our structure provides a detailed picture of the interaction between the dimeric Bre1 RBD and a single Rad6 molecule. We further found that the interaction stimulates Rad6's enzymatic activity by allosterically increasing its active site accessibility and likely contribute to the H2Bub1 catalysis through additional mechanisms. In line with these important functions, we found that the interaction is crucial for multiple H2Bub1-regulated processes. Our study provides molecular insights into the H2Bub1 catalysis.
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Histonas , Proteínas de Saccharomyces cerevisiae , Histonas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Enzimas Ubiquitina-Conjugadoras/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , UbiquitinaciónRESUMEN
Gas emitted from landfills contains a large quantity of volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs), some of which are carcinogenic, teratogenic, and mutagenic, thereby posing a serious threat to the health of landfill workers and nearby residents. However, the global hazards of VOCs and SVOCs in landfill gas to human health remain unclear. To quantify the global risk distributions of these pollutants, we collected the composition and concentration data of VOCs and SVOCs from 72 landfills in 20 countries from the core database of Web of Science and assessed their human health risks as well as analyzed their influencing factors. Organic compounds in landfill gas were found to primarily result from the biodegradation of natural organic waste or the emissions and volatilization of chemical products, with the concentration range of 1 × 10-1-1 × 106 µg/m3. The respiratory system, in particular, lung was the major target organ of VOCs and SVOCs, with additional adverse health impacts ranging from headache and allergies to lung cancer. Aromatic and halogenated compounds were the primary sources of health risk, while ethyl acetate and acetone from the biodegradation of natural organic waste also exceeded the acceptable levels for human health. Overall, VOCs and SVOCs affected residents within 1,000 m of landfills. Air temperature, relative humidity, air pressure, wind direction, and wind speed were the major factors that influenced the health risks of VOCs and SVOCs. Currently, landfill risk assessments of VOCs and SVOCs are primarily based on respiratory inhalation, with health risks due to other exposure routes remaining poorly elucidated. In addition, potential health risks due to the transport and transformation of landfill gas emitted into the atmosphere should be further studied.
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Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Humanos , Compuestos Orgánicos Volátiles/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Medición de Riesgo , Instalaciones de Eliminación de ResiduosRESUMEN
Accurately detecting dynamic changes in bioactive small molecules in real-time is very challenging. In this study, a hemin-based peptide assembly was rationally designed for the colorimetric detection of active small molecules. Hemin-functionalized peptide nanotubes were obtained through the direct incubation of hemin (hemin@PNTs) and peptide nanotubes (PNTs) or were coassembled with the heptapeptide Ac-KLVFFAL-NH2 via electrostatic, π-π stacking, and hydrophobic interactions (hemin-PNTs). This new substance is significant because it exhibits the benefits of both hemin and PNTs as well as some special qualities. First, hemin-PNTs exhibited higher intrinsic peroxidase-like activity, which, in the presence of H2O2, could catalyze the oxidation of the substrate 3,3',5,5'-tetramethylbenzidine (TMB) to yield a typical blue solution after 10 min at 25 â. Second, hemin-PNTs showed significantly higher activity than that of hemin, PNTs alone, or hemin@PNTs. Hemin-PNTs with a 20.0% hemin content may cooperate to improve catalytic activity. The catalytic activity was dependent on the reaction temperature, pH, reaction time, and H2O2 concentration. The nature of the TMB-catalyzed reaction may arise from the production of hydroxyl radicals. Fluorescence analysis was used to demonstrate the catalytic mechanism. According to this investigation, a new highly selective and sensitive colorimetric technique for detecting glutathione (GSH), L-cysteine, and glucose was established. The strategy demonstrated excellent sensitivity for GSH in the range of 1 to 30 µM with a 0.51 µM detection limit. Importantly, this glucose detection technique, which employs glucose oxidase and hemin-PNTs, is simple and inexpensive, with a 0.1 µM to 1.0 mM linear range and a 15.2 µM detection limit. Because of their low cost and high catalytic activity, hemin-PNTs are an excellent choice for biocatalysts in a diverse range of potential applications, including applications in clinical diagnostics, environmental chemistry, and biotechnology.
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Tantalum and its alloys are regarded as equipment construction materials for processing aggressive acidic media due to their excellent properties. In this study, the influence of severe rolling (90%) on the dissolution rate of a cold-rolled Ta-4%W sheet in different directions was investigated during immersion testing and the corresponding mechanism was discussed. The results show that the dissolution rate of the cold-rolled sample is significantly lower than that of the undeformed sample. The corrosion resistance followed the sequence of "initial" < "90%-ND" < "90%-RD" < "90%-TD", while the strength is in positive correlation with the corrosion resistance. Severe rolling promotes grain subdivision accompanied by long geometrically necessary boundaries and short incidental dislocation boundaries on two scales in the cold-rolled sample. The volume elements enclosed by geometrically necessary boundaries form preferential crystallographic orientations. Such preferential crystallographic orientations can greatly weaken the electrochemical process caused by adjacent volume elements, resulting in greatly reduced corrosion rates in the severely deformed sample. The unexpected finding provides a new idea for tailoring the structures of tantalum alloys to improve both their strength and corrosion resistance.
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Various studies have proven that phytosterols and phytostanols (PS) are lipid-lowering agents. These compounds play a role in regulating high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), and triglyceride (TG) metabolism. Although various drugs are available and are currently used to treat dyslipidemia, the management of lipid abnormalities during the postmenopausal period remains a challenge. Thus, scientists are trying to develop new strategies to reduce serum lipids concentrations using natural products. However, the impact of PS administration on serum lipids in postmenopausal women remains unclear. Hence, the purpose of this study was to assess the effect of PS supplementation on the lipid profile in postmenopausal women based on a systematic review of the literature and a meta-analysis of randomized controlled trials. PubMed/Medline, Scopus, Embase, and Web of Science were searched to identify suitable papers published until January 18, 2022. We combined the effect sizes with the DerSimonian and Laird method using a random effects model. PS supplementation resulted in a significant decrease in TC (weighted mean difference [WMD]: -16.73 mg/dl) and LDL-C (WMD: -10.06 mg/dl) levels. No effect of PS supplementation on TG (WMD: -1.14 mg/dl) or HDL-C (WMD: -0.29 mg/dl) concentrations was detected. In the stratified analysis, there was a notable reduction in TC and LDL-C levels when the PS dose was ≥2 g/day (TC: -22.22 mg/dl and LDL-C: -10.14 mg/dl) and when PS were administered to participants with a body mass index ≥25 kg/m2 (TC: -20.22 mg/dl and LDL-C: -14.85 mg/dl). PS administration can decrease TC and LDL-C, particularly if the dose of administration is ≥2 g/day and if the participants are overweight or obese. Further high-quality studies are needed to firmly establish the clinical efficacy of PS usage in postmenopausal females.