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Fertilization is a fundamental process of development, and the blocking mechanisms act at the zona pellucida (ZP) and plasma membrane of the egg to prevent any additional sperm from binding, permeating and fusing after fertilization. In clinical practice, some couples undergoing recurrent IVF failures that mature oocytes had abnormal fertilization for unknown reason. Ovastacin encoded by ASTL cleave the ZP protein ZP2 and play a key role in preventing polyspermy. Here, we identified bi-allelic variants in ASTL that are mainly characterized by fertilization problems in humans. All four independent affected individuals had bi-allelic frameshift variants or predicted damaging missense variants, which follow a Mendelian recessive inheritance pattern. The frameshift variants significantly decreased the quantity of ASTL protein in vitro. And all missense variants affected the enzymatic activity that cleaves ZP2 in mouse egg in vitro. Three knock-in female mice (corresponding to three missense variants in patients) all show subfertility due to low embryo developmental potential. This work presents strong evidence that pathogenic variants in ASTL cause female infertility and provides a new genetic marker for the diagnosis of fertilization problems.
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Infertilidade Feminina , Sêmen , Humanos , Masculino , Feminino , Camundongos , Animais , Glicoproteínas da Zona Pelúcida/genética , Glicoproteínas da Zona Pelúcida/metabolismo , Sêmen/metabolismo , Oócitos/metabolismo , Infertilidade Feminina/genética , Fertilização/genética , Metaloproteases/genéticaRESUMO
Chronic graft-versus-host disease (cGVHD) involves multiple organs, but little is known about bone marrow (BM) alterations caused by cGVHD. In mice and humans, we found that cGVHD is associated with BM fibrosis resulting in T cell infiltration, IgG deposition, and hematopoietic dysfunction. Macrophages and Nestin+ mesenchymal stromal cells (MSCs) participated in the process of BM fibrosis during BM cGVHD development. BM macrophage numbers were significantly increased in mice and humans with BM fibrosis associated with cGVHD. Amplified macrophages produced TGF-ß1, which recruited Nestin+ MSCs forming clusters, and Nestin+ MSCs later differentiated into fibroblasts, a process mediated by increased TGF-ß/Smad signaling. TLR4/MyD88-mediated activation of endoplasmic reticulum (ER) stress in macrophages is associated with fibrosis by increasing Nestin+ MSC migration and differentiation into fibroblasts. Depletion of macrophages by clodronate-containing liposomes and inhibition of ER stress by 4-phenylbutyric acid reversed BM fibrosis by inhibiting fibroblast differentiation. These studies provide insights into the pathogenesis of BM fibrosis during cGVHD development.
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Síndrome de Bronquiolite Obliterante , Células-Tronco Mesenquimais , Humanos , Animais , Camundongos , Medula Óssea , Nestina , MacrófagosRESUMO
BACKGROUND: Taxol, derived from Taxus trees, is a valuable natural resource for the development of anticancer drugs. Endophytic fungi from Taxus trees are a promising alternative source of Taxol. However, the impact of plant-endophytic microbial interaction on the host's Taxol biosynthesis is largely unknown. RESULTS: In the current study, the diversity of endophytic fungi in three different Taxus species was analyzed using Internal Transcribed Spacer sequencing. A total of 271 Operational Taxonomic Units (OTUs) were identified, grouping into 2 phyla, 8 classes, 16 orders, 19 families, and 19 genera. Alpha and beta diversity analysis indicated significant differences in endophytic fungal communities among the various Taxus trees. At the genus level, Alternaria and Davidiella were predominantly found in T. mairei and T. media, respectively. By utilizing a previously published dataset, a Pearson correlation analysis was conducted to predict the taxol biosynthesis-related fungal genera. Following screening, two isolates of Alternaria (L7 and M14) were obtained. Effect of inoculation with Alternaria isolates on the gene expression and metabolite accumulation of T. mairei was determined by transcriptomic and untargeted metabolomic studies. The co-inoculation assay suggests that the two Alternaria isolates may have a negative regulatory effect on taxol biosynthesis by influencing hormone signaling pathways. CONCLUSION: Our findings will serve as a foundation for advancing the production and utilization of Taxus and will also aid in screening endophytic fungi related to taxol production.
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Alternaria , Endófitos , Paclitaxel , Taxus , Taxus/microbiologia , Paclitaxel/biossíntese , Endófitos/genética , Endófitos/metabolismo , Endófitos/isolamento & purificação , Endófitos/classificação , Alternaria/genética , Alternaria/metabolismo , Alternaria/classificação , Alternaria/isolamento & purificação , Filogenia , Fungos/genética , Fungos/metabolismo , Fungos/classificação , Fungos/isolamento & purificação , DNA Fúngico/genética , DNA Espaçador Ribossômico/genéticaRESUMO
We propose and experimentally demonstrate a dual-wavelength distributed feedback (DFB) laser array utilizing a four-phase-shifted sampled Bragg grating. By using this grating, the coupling coefficient is enhanced by approximately 2.83 times compared to conventional sampled Bragg gratings. The devices exhibit a stable dual-mode lasing achieved by introducing further π-phase shifts at 1/3 and 2/3 positions along the cavity. These devices require only one stage of lithography to define both the ridge waveguide and the gratings, mitigating issues related to misalignment between them. A dual-wavelength laser array has been fabricated with frequency spacings of 320â GHz, 500â GHz, 640â GHz, 800â GHz, and 1â THz. When integrated with semiconductor optical amplifiers, the output power of the device can reach 23.6â mW. Furthermore, the dual-wavelength lasing is maintained across a wide range of injection currents, with a power difference of <3â dB between the two primary modes. A terahertz (THz) signal has been generated through photomixing in a photoconductive antenna, with the measured power reaching 12.8â µW.
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Direct photoreduction of FeIII is a widely recognized route for accelerating FeIII/FeII cycle in photo-Fenton chemistry. However, most of the wavelengths covering the full spectral range are insufficient to supply enough photon energy for the direct reduction process. Herein, the hitherto neglected mechanism of FeIII reduction that the FeIII indirect reduction pathway initiated by light energy-dependent reactivity variation and reactive excited state (ES) was explored. Evolution of excited-state FeIII species (*FeIII) resulting from metal-centered charge excitation (MCCE) of FeIII is experimentally verified using pulsed laser femtosecond transient absorption spectroscopy with UV-vis detection and theoretically verified by quantum chemical calculation. Intense photoinduced intravalence charge transition was observed at λ = 380 and 466 nm, revealing quartet 4MCCE and doublet 2MCCE and their exponential processes. Light energy-dependent variation of *FeIII reactivity was kinetically certified by fitting the apparent rate constant of the radical-chain sequence of photo-Fenton reactions. Covalency is found to compensate for the intravalence charge separation following photoexcitation of the metal center in the MCCE state of Fenton photosensitizer. The *FeIII is established as a model, demonstrating the intravalence hole delocalization in the ES can be leveraged for photo-Fenton reaction or other photocatalytic schemes based on electron transfer chemistry.
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Ferro , Ferro/química , Oxirredução , Peróxido de Hidrogênio/química , CinéticaRESUMO
2-ethylhexyl diphenyl phosphate (EHDPHP) is a widely used organophosphorus flame retardant and plasticizer, which is commonly found in the environment. EHDPHP not only potentially harms the environment but also causes different degrees of damage to the organism. In this study, the duodenum of chicks was selected as the potential toxic target organ to explore the mechanism of duodenal injury induced by EHDPHP exposure. Ninety one-day-old healthy male chicks were selected and randomly divided into C1(control group), C2(solvent control group), L(800â¯mg/kg), M(1600â¯mg/kg), H(3200â¯mg/kg) according to different doses of EHDPHP after one week of environmental adaptation. The chicks were given continuous gavage for 14 d, 28 d, and 42 d. It was found that constant exposure to EHDPHP caused an increase in duodenal MDA content, a decrease in P-gp, SOD, GSH-Px activities, and a decrease in duodenal mucosal immune factor (sIgA, GSH-Px). The expression of sIgM and mucosal link proteins (CLDN, OCLN, ZO-1, JAM) decreased, and the expression of the inflammatory protein (NF-κB, COX2) in duodenal tissues was up-regulated. The results showed that continuous exposure to EHDPHP could cause duodenal oxidative stress, inflammation, and mucosal barrier damage in chicks, which provided a basis for studying the mechanism of toxic damage caused by EHDPHP in poultry.
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Galinhas , Duodeno , Retardadores de Chama , Estresse Oxidativo , Animais , Estresse Oxidativo/efeitos dos fármacos , Duodeno/efeitos dos fármacos , Duodeno/patologia , Duodeno/metabolismo , Masculino , Retardadores de Chama/toxicidade , Inflamação/induzido quimicamente , Inflamação/patologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Mucosa Intestinal/metabolismo , Compostos Organofosforados/toxicidade , Organofosfatos/toxicidadeRESUMO
Many gastrointestinal simulation methods have been used to predict bioavailability, but the suitability of different methods for the same metal(loid)s varies widely, which inevitably affects the accuracy of human health risk assessment. Arsenic is a common and important contaminant in many contaminated land situations. It can be readily absorbed and has teratogenic and mutagenic toxicity. Therefore, in this study, four the most commonly used in vitro simulation methods (the Physiologically Based Extraction Test (PBET), In Vitro Gastrointestinal Method (IVG), Soluble Bioavailability Research Consortium (SBRC), the Unified BARGE Method (UBM)) were tested against an in vivo animal live model, to evaluate their effectiveness for the prediction of soil As bioavailability in 10 industrially contaminated soils. The soil As relative bioavailability (RBA) varied between 15% and 68% in the different soils. As bioaccessibility differed between the 4 gastro-intestinal simulation methods. Gastric phase of UBM (UBMG) predicted As relative bioavailability the best of the 4 assays (R2 = 0.81). This study provides theoretical and technical support to refine human health risk assessment of As in soils from urban industrial legacy contaminated sites.
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Arsênio , Poluentes do Solo , Animais , Humanos , Arsênio/análise , Solo , Disponibilidade Biológica , Poluentes do Solo/análise , Poluição AmbientalRESUMO
OBJECTIVE: This study aimed to assess the clinical efficacy of acupuncture combined with modified Blood and Vessel Expelling Blood Stasis Tang in the treatment of poststroke patients experiencing facial paralysis and insomnia. METHODS: A total of 120 patients with poststroke facial paralysis and insomnia were selected from the Department of Acupuncture and Moxibustion at the First Affiliated Hospital of Tianjin University of Traditional Chinese Medicine between January 2021 and January 2023. They were randomly assigned to either a control group or a study group, with 60 patients in each group. The control group received conventional treatment, while the study group received acupuncture combined with modified Blood and Vessel Expelling Blood Stasis Tang. The neurological function, facial paralysis, and sleep quality of the patients in both groups were compared. RESULTS: The study group exhibited a significantly higher total effective rate compared with the control group (86.67% versus 66.67%). After treatment, both groups showed a significant reduction in National Institutes of Health Stroke Scale scores, with the study group demonstrating significantly lower scores than the control group. The Functional Disability Index scores for somatic functioning and social life functioning significantly improved in both groups after treatment, with the study group achieving significantly lower scores compared with the control group. The Sleep-Related Symptom Scale and Pittsburgh Sleep Quality Index scores significantly decreased in both groups after treatment, with the study group achieving significantly lower scores than the control group. CONCLUSIONS: Acupuncture combined with modified Blood and Vessel Expelling Blood Stasis Tang effectively promotes recovery of neurological function and significantly improves facial paralysis and insomnia in patients with poststroke facial paralysis and insomnia. However, further research is warranted to validate these findings.
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BACKGROUND: Global food loss and waste have raised environmental concerns regarding the generation of greenhouse gases (e.g., carbon dioxide and methane gas), which directly contribute to climate change. To address these concerns, the present research aims to upcycle food waste into an alternative culture medium for the cultivation of microalgae. Various parameters including pretreatment of food waste (i.e., autoclave and non-autoclave), concentration of food waste culture medium (i.e., 10%, 30%, 50%, 70%, 90% and 100%), harvesting efficiency and biochemical compounds of Chlorella sp. microalgae were carried out. RESULTS: Based on the preliminary findings, the highest biomass concentration obtained from 10% food waste culture medium in the autoclave for Chlorella sp., including strains FSP-E, ESP-31 and CY-1, were 2.869 ± 0.022, 2.385 ± 0.018 and 0.985 ± 0.0026 g L-1, respectively. Since Chlorella vulgaris FSP-E exhibited the highest biomass concentration, this microalgal strain was selected to examine the subsequent parameters. Cultivation of C. vulgaris FSP-E in 100FW achieves a biomass concentration of 4.465 ± 0.008 g L-1 with biochemical compounds of 6.94 ± 1.396, 248.24 ± 0.976 and 406.23 ± 0.593 mg g-1 for lipids, carbohydrates and proteins, respectively. CONCLUSION: This study shows that using food waste as an alternative culture medium for C. vulgaris FSP-E can achieve substantial biomass productivity and biochemical content. This research work would contribute to the concept of net zero emission and transitioning toward a circular bioeconomy by upcycling food waste as an alternative culture medium for the cultivation of microalgae. © 2024 Society of Chemical Industry.
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We simulate and demonstrate experimentally an inner-wall grating double slot micro ring resonator (IG-DSMRR) with a center slot ring radius of only 6.72 µm based on the silicon-on-insulator platform. This novel photonic-integrated sensor for optical label-free biochemical analysis boosts the measured refractive index (RI) sensitivity in glucose solutions to 563 nm/RIU with the limit of detection value being 3.7 × 10-6 RIU (refractive index units). The concentration sensitivity for sodium chloride solutions can reach 981 pm/%, with a minimum concentration detection limit of 0.02%. Using the combination of DSMRR and IG, the detection range is enlarged significantly to 72.62 nm, three times the free spectral range of conventional slot micro ring resonators. The measured Q-factor is 1.6 × 104, and the straight strip and double slot waveguide transmission losses are 0.9 dB/cm and 20.2 dB/cm, respectively. This IG-DSMRR combines the advantages of a micro ring resonator, slot waveguide, and angular grating and is highly desirable for biochemical sensing in liquids and gases offering an ultra-high sensitivity and ultra-large measurement range. This is the first report of a fabricated and measured double-slot micro ring resonator with an inner sidewall grating structure.
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Integrated microring resonator structures based on silicon-on-insulator (SOI) platforms are promising candidates for high-performance on-chip sensing. In this work, a novel sidewall grating slot microring resonator (SG-SMRR) with a compact size (5 µm center radius) based on the SOI platform is proposed and demonstrated experimentally. The experiment results show that the refractive index (RI) sensitivity and the limit of detection value are 620â nm/RIU and 1.4 × 10-4â RIU, respectively. The concentration sensitivity and minimum concentration detection limit are 1120â pm/% and 0.05%, respectively. Moreover, the sidewall grating structure makes this sensor free of free spectral range (FSR) limitation. The detection range is significantly enlarged to 84.5â nm in lab measurement, four times that of the FSR of conventional SMRRs. The measured Q-factor is 3.1 × 103, and the straight slot waveguide transmission loss is 24.2â dB/cm under sensing conditions. These results combined with the small form factor associated with a silicon photonics sensor open up applications where high sensitivity and large measurement range are essential.
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Polarization-sensitive photodetectors in the ultraviolet (UV) region have been favored for their great meaning in the field of military and civilian. UV photodetectors based on GaN have aroused much attention due to high photocurrent and high sensitivity. However, the dependence on external power sources and the limited sensitivity to polarized UV light significantly impede the practical application of these photodetectors in UV-polarized photodetection. Herein, a polarization-sensitive UV photodetector based on ReSe2/GaN mixed-dimensional van der Waals (vdWs) heterojunction is proposed. Owing to the high-quality junction and type-II band alignment, the responsivity and specific detectivity reach values of 870â mA/W and 6.8 × 1011 Jones, under 325â nm illumination, respectively. Furthermore, thanks to the strong in-plane anisotropy of ReSe2, the device is highly sensitive to polarized UV light with a photocurrent anisotropic ratio up to 6.67. The findings are expected to bring new opportunities for the development of highly sensitive, high-speed and energy-efficient polarization-sensitive photodetectors.
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Acute graft-versus-host disease (aGVHD) remains a major limitation of allogeneic hematopoietic stem cell transplantation; not all patients respond to standard glucocorticoids treatment. This study retrospectively evaluated the effects of ruxolitinib compared with basiliximab for steroid-refractory aGVHD (SR-aGVHD). One hundred and twenty-nine patients were enrolled, 81 in ruxolitinib and 48 in basiliximab group. The overall response (OR) at day 28 was higher in ruxolitinib group (72.8% vs. 54.2%, P = 0.031), as with complete response (CR) (58.0% vs. 35.4%, P = 0.013). Ruxolitinib led to significantly lower 1-year cumulative incidence of chronic GVHD (cGVHD) (29.6% vs. 43.8%, P = 0.021). Besides, ruxolitinib showed higher 1-year overall survival (OS) and 1-year cumulative incidence of failure-free survival (FFS) (OS: 72.8% vs. 50.0%, P = 0.008; FFS: 58.9% vs. 39.6%, P = 0.014). The 1-year cumulative incidence of non-relapse mortality (NRM) was lower in ruxolitinib group (16.1% vs. 37.5%, P = 0.005), and the 1-year relapse was not different. The 1-year cumulative incidence of cytomegalovirus (CMV) viremia, CMV-associated diseases and Epstein-Barr virus (EBV)-associated diseases was similar between the two groups, but EBV viremia was significantly lower in ruxolitinib group (6.2% vs. 29.2%, P < 0.001). Subgroup analyses revealed that OR and survival were similar in ruxolitinib 5 mg twice daily (bid) and 10 mg bid groups. However, ruxolitinib 10 mg bid treatment markedly reduced 1-year cumulative incidence of cGVHD compared with 5 mg bid (21.1% vs. 50.0%, P = 0.016). Our study demonstrated that ruxolitinib was superior to basiliximab in SR-aGVHD treatment and cGVHD prophylaxis, therefore should be recommended.
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Síndrome de Bronquiolite Obliterante , Infecções por Citomegalovirus , Infecções por Vírus Epstein-Barr , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Humanos , Basiliximab/uso terapêutico , Estudos Retrospectivos , Viremia , Herpesvirus Humano 4 , Esteroides/uso terapêutico , Nitrilas/uso terapêutico , Doença Enxerto-Hospedeiro/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença AgudaRESUMO
Attaching polymers, especially polyethylene glycol (PEG), to protein drugs has emerged as a successful strategy to prolong circulation time in the bloodstream. The hypothesis is that the flexible chain wobbles on the protein's surface, thus resisting potential nonspecific adsorption. Such a theoretical framework may be challenged when a helical polyglutamate is used to conjugate with target proteins. In this study, we investigated the structure-activity relationships of polyglutamate-interferon conjugates P(EG3Glu)-IFN using molecular simulations. Our results show that the local crowding effect induced by oligoethylene glycols (i.e., EG3) is the primary driving force for helix formation in P(EG3Glu), and its helicity can be effectively increased by reducing the free volume of the two termini. Furthermore, it was found that the steric hindrance induced by IFN is not conductive to the helicity of P(EG3Glu) but contributes to its dominant orientation relative to interferon. The orientation of IFN relative to the helical P(EG3Glu) can help to protect the protein drug from neutralizing antibodies while maintaining its bioactivity. These findings suggest that the helical structure and its orientation are critical factors to consider when updating the theoretical framework for protein-polymer conjugates.
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Interferons , Ácido Poliglutâmico , Interferons/química , Polietilenoglicóis/química , Polímeros/química , ProteínasRESUMO
Effective amelioration of ischemia/reperfusion (I/R)-induced intestinal injury and revealing its mechanisms remain the challenges in both preclinic and clinic. Potential mechanisms of naringin in ameliorating I/R-induced intestinal injury remain unknown. Based on pre-experiments, I/R-injured rat intestine in vivo and hypoxia-reoxygenation (H/R)-injured IEC-6 cells in vitro were used to verify that naringin-alleviated I/R-induced intestinal injury was mediated via deactivating cGAS-STING signaling pathway. Naringin improved intestinal damage using hematoxylin and eosin staining and decreased alanine aminotransferase and aspartate aminotransferase contents in plasma. Naringin decreased inflammation characterized by reducing IL-6, IL-1ß, TNF-α, and IFN-ß contents in both plasma and IEC-6 cells. Naringin mitigated oxidative stress via recovering superoxide dismutase, glutathione, and malondialdehyde levels in the I/R-injured intestine. Naringin reduced the expression of apoptotic proteins, including Bax, caspase-3, and Bcl-2, and reduced terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling-positive cells both in vivo and in vitro, and decreased Hoechst 33342 signals in vitro. cGAS, STING, p-TBK1, p-IRF3, and NF-κB expressions were up-regulated both in vivo and in vitro respectively and the up-regulated indexes were reversed by naringin. Transfection of cGAS-siRNA and cGAS-cDNA significantly down-regulated and up-regulated cGAS-STING signaling-related protein expressions, respectively, and partially weakened naringin-induced amelioration on these indexes, suggesting that deactivation of cGAS-STING signaling is the crucial target for naringin-induced amelioration on I/R-injured intestine.
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Intestinos , Traumatismo por Reperfusão , Ratos , Animais , Transdução de Sinais , Inflamação/tratamento farmacológico , Nucleotidiltransferases/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , ApoptoseRESUMO
At present, the explosive growth of software code volume and quantity makes the code review process very labor-intensive and time-consuming. An automated code review model can assist in improving the efficiency of the process. Tufano et al., designed two automated tasks to help improve the efficiency of code review based on the deep learning approach, from two different perspectives, namely, the developer submitting the code and the code reviewer. However, they only used code sequence information and did not explore the logical structure information with a richer meaning of the code. To improve the learning of code structure information, a program dependency graph serialization algorithm PDG2Seq algorithm is proposed, which converts the program dependency graph into a unique graph code sequence in a lossless manner, while retaining the program structure information and semantic information. We then designed an automated code review model based on the pre-trained model CodeBERT architecture, which strengthens the learning of code information by fusing program structure information and code sequence information, and then fine-tuned the model according to the code review activity scene to complete the automatic modification of the code. To verify the efficiency of the algorithm, the two tasks in the experiment were compared with the best Algorithm 1-encoder/2-encoder. The experimental results show that the model we proposed has a significant improvement under the BLEU, Lewinshtein distance and ROUGE-L metrics.
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Bacillus cereus (B. cereus) is a common foodborne pathogen causing food poisoning incidents. This study aimed to evaluate the antibacterial activity and underlying mechanism of rhamnolipids (RLs) against B. cereus. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of RLs for B. cereus were determined to be 16.0 mg/L and 32.0 mg/L, respectively. Scanning electron microscopy and fluorescence microscope images, as well as data of membrane potential, relative electric conductivity, and leakage of intracellular components revealed that RLs disrupted the integrity of the cell membrane. Furthermore, the reactive oxygen species content, catalase (CAT) and superoxide dismutase (SOD) activity indicated that RLs activated the oxidative stress response of B. cereus in response to RLs. Fresh wet noodles (FWN) were used as a food model, and RLs showed a significant killing effect on B. cereus with a sustained inhibitory effect at the concentrations ranging from 128.0 to 1024.0 mg/kg. Additionally, RLs promoted the conversion of free water to bound water in FWN, which improved the storage of FWN and made the taste more resilient and chewy. These results suggest that RLs could be a potential alternative to antimicrobial agents and preservatives for applications in food processing.
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Anti-Infecciosos , Bacillus cereus , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Água/farmacologiaRESUMO
A novel gas-pressurized (GP) torrefaction method at 250 °C has recently been developed that realizes the deep decomposition of cellulose in lignocellulosic solid wastes (LSW) to as high as 90% through deoxygenation and aromatization reactions. However, the deoxygenation and aromatization mechanisms are currently unclear. In this work, these mechanisms were studied through a developed molecular structure calculation method and the GP torrefaction of pure cellulose. The results demonstrate that GP torrefaction at 250 °C causes 47 wt.% of mass loss and 72 wt.% of O removal for cellulose, while traditional torrefaction at atmospheric pressure has almost no impact on cellulose decomposition. The GP-torrefied cellulose is determined to be composed of an aromatic furans nucleus with branch aliphatic C through conventional characterization. A molecular structure calculation method and its principles were developed for further investigation of molecular-level mechanisms. It was found 2-ring furans aromatic compound intermediate is formed by intra- and inter-molecular dehydroxylation reactions of amorphous cellulose, and the removal of O-containing function groups is mainly through the production of H2O. The three-ring furans aromatic compound intermediate and GP-torrefied cellulose are further formed through the polymerization reaction, which enhances the removal of ketones and aldehydes function groups in intermediate torrefied cellulose and form gaseous CO and O-containing organic molecules. A deoxygenation and aromatization mechanism model was developed based on the above investigation. This work provides theoretical guidance for the optimization of the gas-pressurized torrefaction method and a study method for the determination of molecular-level structure and the mechanism investigation of the thermal conversion processes of LSW.
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Risk assessment has been recognized as an important tool for evaluating heavy metal pollution and providing risk-based information for decision makers. In order to accurately assess the risk of heavy metals in contaminated soil to human health, it is necessary to conduct bioavailability studies on heavy metals in soil. Bioavailability of heavy metals in soils and the implications for risk assessment and land management/remediation has evolved over the decades and now has considerable practical and economic implications internationally. This article aims to explore its evolution by undertaking a bibliometric analysis of the research fields which have addressed heavy metal bioavailability in soils, with a focus on the risk assessment of contaminated land and human exposure to soil-borne metals. Bibliometric analysis techniques are applied to monitor and assess the changing research literature on the bioavailability of heavy metals in contaminated soils. Over 5000 articles were found for the period 1979-2020. The purpose was not to perform an exhaustive literature review, but to draw out trends and patterns in the literature, and to make observations on past and current priorities. Key words were extracted from the analysis and the roles of different countries in driving the research literature identified. Three phases in literature/subject development were identified. Between 1979 and 2000 (initial phase, 213 articles), studies used extraction procedures and solubility studies to investigate the roles of soil properties on metal form/speciation and focused on bioavailability to (crop) plants in agricultural soils. Between 2001 and 2010 (slow development phase, 1105 articles), attention switched to metals introduced in soil amendments and wastes, metal impacts on soil microbial processes, and incorporating bioavailability in risk assessment. More rigorous techniques were being used, such as the diffusive gradients in thin films technique, to better understand kinetic and metal speciation in soils and the quantitative relationship to bioavailability. By 2011-2020 (rapid development phase, 3137 articles), research was being conducted in many countries (site specific, often industrially contaminated and urban sites), with a focus shift to health risk assessment, remediation, and bioavailability to various ecological receptors (e.g., humans and animals), with the development of many methods of bioavailability (e.g., simulated gastrointestinal tract enzymolysis methods). Some priorities for research on soil heavy metal bioavailability are identified.
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Metais Pesados , Poluentes do Solo , Humanos , Disponibilidade Biológica , Poluentes do Solo/análise , Metais Pesados/análise , Medição de Risco , SoloRESUMO
Objective: To investigate the effect of sleep deprivation on the metabolism of the hippocampal region in mice. Methods: The mice were randomly assigned to three groups, a control group, a 24-h sleep deprivation (SD) group, and a 48-h SD group. Each group had 10 mice. The sleep deprivation model was induced by the modified multiple platform method. The mice's anxiety-like behaviors were assessed with the open field test (OFT) and their depression-like behaviors were assessed with the sucrose preference test (SPT), the forced swimming test (FST), and tail suspension test (TST). High performance liquid chromatography (HPLC) was performed to determine the levels of 6 monoamine neurotransmitters, including 5-hydroxytryptamine (5-HT), norepinephrine (NE), dopamine (DA), gamma-aminobutyric acid (GABA), 5-dihydroxyphenylacetic acid (5-DOPAC), and homovanillic acid (HVA), and 4 amino acids, including glutamic acid (Glu), aspartic acid (Asp), serine (Ser), and taurine (Tau), in the hippocampal region. Immunofluorescence staining was performed to examine the expression of glial cells in the hippocampal region of the mice. The main indicators measured were the levels of monoamine neurotransmitters and amino acids. Results: According to the results of the behavioral analysis, in comparison with the findings for the control group, the 24-h SD mice exhibited increased consumption of sucrose in SFT, significantly decreased total immobility time in FST and TST, and increased total distance covered in OFT, while the 48-h SD mice showed decreased consumption of sucrose in SFT, prolonged total immobility time in FST and TST, and decreased total distance covered in OFT. The results of the HPLC analysis of the monoamine neurotransmitter showed that 24-h SD mice had in their hippocampal region increased levels of DA (P<0.001) and NE (P<0.01) and decreased levels of GABA (P<0.05) in comparison with those of the control mice, while their 5-HT, 5-DOPAC, and HVA levels were not significantly different from those of the control mice. In comparison with those of the control mice, the 48-h SD mice had, in their hippocampal region, decreased levels of 5-HT and NE (all P<0.05), decreased DA (P<0.01), and increased level of GABA (P<0.01), while the levels of 5-DOPAC and HAV were not significantly different. The 48-h SD group showed a significant decrease in the levels of Tau and Glu in comparison with those of the 24-h SD group (all P<0.05). According to the results of immunofluorescence assay, there was no significant difference between the control group and the 24-h SD group in the cell count of glial fibrillary acidic protein (GFAP)-positive cells, while a decline in GFAP-positive cells in comparison with that of the control group was observed in the 48-h SD group. Conclusion: SD of 24 hours may induce anxiety-like behavioral changes in mice by activating their hippocampal glial cells, upregulating the levels of 5-HT, DA, and NE, and increasing the levels of Glu and Tau in the hippocampal region. SD of 48 hours may induce depression-like behavioral changes in mice by inhibiting the activation of glial cells in the hippocampal region and regulating in the opposite direction the levels of the above-mentioned monoamine neurotransmitters and amino acids in the hippocampal region.