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Rhus chinensis Mill., an economically valuable Anacardiaceae species, is parasitized by the galling aphid Schlechtendalia chinensis, resulting in the formation of the Chinese gallnut (CG). Here, we report a chromosomal-level genome assembly of R. chinensis, with a total size of 389.40 Mb and scaffold N50 of 23.02 Mb. Comparative genomic and transcriptome analysis revealed that the enhanced structure of CG and nutritional metabolism contribute to improving the adaptability of R. chinensis to S. chinensis by supporting CG and galling aphid growth. CG was observed to be abundant in hydrolysable tannins (HT), particularly gallotannin and its isomers. Tandem repeat clusters of dehydroquinate dehydratase/shikimate dehydrogenase (DQD/SDH) and serine carboxypeptidase-like (SCPL) and their homologs involved in HT production were determined as specific to HT-rich species. The functional differentiation of DQD/SDH tandem duplicate genes and the significant contraction in the phenylalanine ammonia-lyase (PAL) gene family contributed to the accumulation of gallic acid and HT while minimizing the production of shikimic acid, flavonoids, and condensed tannins in CG. Furthermore, we identified one UDP glucosyltransferase (UGT84A), three carboxylesterase (CXE), and six SCPL genes from conserved tandem repeat clusters that are involved in gallotannin biosynthesis and hydrolysis in CG. We then constructed a regulatory network of these genes based on co-expression and transcription factor motif analysis. Our findings provide a genomic resource for the exploration of the underlying mechanisms of plant-galling insect interaction and highlight the importance of the functional divergence of tandem duplicate genes in the accumulation of secondary metabolites.
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Genoma de Planta , Taninos Hidrolisáveis , Rhus , Taninos Hidrolisáveis/metabolismo , Animais , Rhus/genética , Genoma de Planta/genética , Afídeos/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Cromossomos de Plantas/genética , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-ParasitaRESUMO
Valorization of microalgae into high-value products and drop-in chemicals can reduce our dependence on non-renewable fossil fuels in an environmentally sustainable way. Among the valuable products, medium-chain carboxylic acids (MCCAs) and alcohols are attractive building blocks as fuel precursors. However, the biosynthetic mechanisms of MCCAs and alcohols in anaerobic microalgae fermentation and the regulating role of pH on the microbial structure and metabolism interaction among different functional groups have never been documented. In this work, we systematically investigated the roles of pH (5, 7, and 10) on the production of MCCAs and alcohols in anaerobic microalgae fermentation. The gene-centric and genome-centric metagenomes were employed to uncover the dynamics and metabolic network of the key players in the microbial communities. The results indicated that the pH significantly changed the product spectrum. The maximum production rate of alcohol was obtained at pH 5, while pH 7 was more beneficial for MCCA production. Metagenomic analysis reveals that this differential performance under different pH is attributed to the transformation of microbial guild and metabolism regulated by pH. The composition of various functional groups for MCCA and alcohol production also varies at different pH levels. Finally, a metabolic network was proposed to reveal the microbial interactions at different pH levels and thus provide insights into bioconversion of microalgae to high-value biofuels.IMPORTANCECarboxylate platforms encompass a biosynthesis process involving a mixed and undefined culture, enabling the conversion of microalgae, rich in carbohydrates and protein, into valuable fuels and mitigating the risks associated with algae blooms. However, there is little known about the effects of pH on the metabolic pathways of chain elongation and alcohol production in anaerobic microalgae fermentation. Moreover, convoluted and interdependent microbial interactions encumber efforts to characterize how organics and electrons flow among microbiome members. In this work, we compared metabolic differences among three different pH levels (5, 7, and 10) in anaerobic microalgae fermentation. In addition, genome-centric metagenomic analysis was conducted to reveal the microbial interaction for medium-chain carboxylic acid and alcohol production.
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Ácidos Carboxílicos , Microalgas , Fermentação , Ácidos Carboxílicos/metabolismo , Microalgas/metabolismo , Anaerobiose , Etanol/metabolismo , Concentração de Íons de HidrogênioRESUMO
Systemic lupus erythematosus (SLE) is an autoimmune disease in which defective T cells, immune complex deposition and other immune system alterations contribute to pathological changes of multiple organ systems. The vitamin D metabolite c is a critical immunomodulator playing pivotal roles in the immune system. Epidemiological evidence indicates that vitamin D deficiency is correlated with the severity of SLE. Our aim is to investigate the effects of 1,25(OH)2D3 (VitD3) on the activation of myeloid dendritic cells (mDCs) by autologous DNA-containing immune complex (DNA-ICs), and the effects of VitD3 on immune system balance during SLE. We purified DNA-ICs from the serum of SLE patients and isolated mDCs from normal subjects. In vitro studies showed that DNA-ICs were internalized and consumed by mDCs. VitD3 blocked the effects of DNA-ICs on RelB, IL-10 and TNF-α in mDCs. Further analysis indicated that DNA-ICs stimulated histone acetylation in the RelB promoter region, which was inhibited by VitD3. Knockdown of the histone deacetylase 3 gene (HDAC3) blocked these VitD3-mediated effects. Co-culture of mDCs and CD4+ T cells showed that VitD3 inhibited multiple processes mediated by DNA-ICs, including proliferation, downregulation of IL-10, TGF-ß and upregulation of TNF-α. Moreover, VitD3 could also reverse the effects of DNA-IC-induced imbalance of CD4+ CD127- Foxp3+ T cells and CD4+ IL17+ T cells. Taken together, our results indicated that autologous DNA-ICs stimulate the activation of mDCs in the pathogenesis of SLE, and VitD3 inhibits this stimulatory effects of DNA-ICs by negative transcriptional regulation of RelB gene and maintaining the Treg/Th17 immune cell balance. These results suggest that vitamin D may have therapeutic value for the treatment of SLE.
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Colecalciferol , Lúpus Eritematoso Sistêmico , Humanos , Colecalciferol/farmacologia , Interleucina-10 , Complexo Antígeno-Anticorpo , Fator de Necrose Tumoral alfa , Inflamação , Vitamina D/farmacologia , Células Dendríticas/metabolismo , DNARESUMO
INTRODUCTION: Atopy is an important and non-negligible clinical phenomenon in chronic spontaneous urticaria (CSU). However, the characteristics and clinical significance of atopy in patients with CSU have not been fully described. This study aimed to analyze the characteristics and clinical significance of atopy in patients with CSU. METHODS: A descriptive cross-sectional design was used. The study enrolled 176 patients with CSU. All enrolled patients underwent total IgE, specific IgE, and autologous serum skin tests (ASSTs). The relationships between atopy, the demographic and clinical data of patients with CSU, and the response to ASST were analyzed in detail; the distribution of allergens in atopic CSU was also analyzed. RESULTS: Atopy was confirmed in 48.9% of patients with CSU. Patients with atopic CSU were more likely than patients with non-atopic CSU to have dermatographism (57.0% vs. 41.1%, p < 0.05), history of urticaria (37.2% and 18.9%, respectively; p < 0.01), angioedema (39.5% and 24.4%, respectively; p < 0.05), and anaphylaxis (7/86 and 1/90, respectively; p < 0.05). Atopy was not associated with ASST response, disease duration, or response to antihistamine treatment in patients with CSU, nor was it associated with the urticaria activity score (UAS7), chronic urticaria quality of life questionnaire (CU-Q2oL), or pruritus visual analog scale (VAS) scores (all p < 0.05). The most common allergen in patients with atopic CSU was dust mites, followed by animal food allergens, tree/grass pollen, and cockroaches. CONCLUSIONS: Although larger prospective studies are needed to confirm these results, our study found atopy occurred in nearly half of patients with CSU, and preliminarily links atopy to CSU, suggesting it as a potential risk factor for angioedema, anaphylaxis, and recurrent urticaria, mirroring allergen patterns in other allergic disease.
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OBJECTIVES: To investigate the evidence of ferroptosis in peripheral blood mononuclear cells (PBMCs) from patients with systemic lupus erythematosus (SLE). METHODS: PBMCs were collected from 30 patients diagnosed as SLE and without any standardised treatment previously and 10 healthy controls. Meanwhile the clinical and laboratory data were collected. The intracellular Fe2+, reactive oxygen species (ROS) and lipid peroxidation (LPO) were detected by fluorescence probe and flow cytometry. The morphology of cells and intracellular organelles were observed by transmission electron microscopy. RT-qPCR and Western blot were applied to compare the expression of GPX4 in PBMCs. RESULTS: The concentration of Fe2+, levels of ROS and LPO in PBMCs from SLE patients were significantly higher than those in healthy controls (p<0.05), and significant differences between the two groups were observed in CD14+ monocytes, CD19+B cells, and CD56+ NK cells respectively. The more prominent differences were observed in SLE patients with renal involvement, liver injury and higher disease activity score. There was no significant difference in GPX4 mRNA expression between SLE patients and healthy controls, however GPX4 protein expression was significantly lower in SLE patients compared to healthy controls, with a negative correlation with the SLE disease activity index. Transmission electron microscopy revealed typical morphological features of ferroptosis such as decreased mitochondrial volume, increased mitochondrial membrane density, and disappearance of mitochondrial cristas. CONCLUSIONS: Ferroptosis occurred more frequently in PBMCs of SLE patients than healthy controls, including CD14+ monocytes, CD19+B cells, CD56+ NK cells, and so on, with negative association with SLE disease activity, which indicated the correlation between ferroptosis with the pathogenesis of SLE.
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Ferroptose , Lúpus Eritematoso Sistêmico , Humanos , Leucócitos Mononucleares/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Lúpus Eritematoso Sistêmico/diagnóstico , Citometria de FluxoRESUMO
Sewage sludge, as a carbon-rich byproduct of wastewater treatment, holds significant untapped potential as a renewable resource. Upcycling this troublesome waste stream represents great promise in addressing global escalating energy demands through its wide practice of biochemical recovery concurrently. Here, we propose a biotechnological concept to gain value-added liquid bioproducts from sewage sludge in a self-sufficient manner by directly transforming sludge into medium-chain fatty acids (MCFAs). Our findings suggest that yeast, a cheap and readily available commercial powder, would involve ethanol-type fermentation in chain elongation to achieve abundant MCFA production from sewage sludge using electron donors (i.e., ethanol) and acceptors (i.e., short-chain fatty acids) produced in situ. The enhanced abundance and transcriptional activity of genes related to key enzymes, such as butyryl-CoA dehydrogenase and alcohol dehydrogenase, affirm the robust capacity for the self-sustained production of MCFAs. This is indicative of an effective metabolic network established between yeast and anaerobic microorganisms within this innovative sludge fermentation framework. Furthermore, life cycle assessment and techno-economic analysis evidence the sustainability and economic competitiveness of this biotechnological strategy. Overall, this work provides insights into sewage sludge upgrading independent of additional carbon input, which can be applied in existing anaerobic sludge fermentation infrastructure as well as to develop new applications in a diverse range of industries.
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Fermentação , Esgotos , Biotecnologia/métodos , Ácidos Graxos/metabolismoRESUMO
The feasibility of a synergistic endogenous partial denitrification-phosphorus removal coupled anammox (SEPD-PR/A) system was investigated in a modified anaerobic baffled reactor (mABR) for synchronous carbon, nitrogen, and phosphorus removal. The mABR comprising four identical compartments (i.e., C1-C4) was inoculated with precultured denitrifying glycogen-accumulating organisms (DGAOs), denitrifying polyphosphate-accumulating organisms, and anammox bacteria. After 136 days of operation, the chemical oxygen demand (COD), total nitrogen, and phosphorus removal efficiencies reached 88.6 ± 1.0, 97.2 ± 1.5, and 89.1 ± 4.2%, respectively. Network-based analysis revealed that the biofilmed community demonstrated stable nutrient removal performance under oligotrophic conditions in C4. The metagenome-assembled genomes (MAGs) such as MAG106, MAG127, MAG52, and MAG37 annotated as denitrifying phosphorus-accumulating organisms (DPAOs) and MAG146 as a DGAO were dominated in C1 and C2 and contributed to 89.2% of COD consumption. MAG54 and MAG16 annotated as Candidatus_Brocadia (total relative abundance of 16.5% in C3 and 4.3% in C4) were responsible for 74.4% of the total nitrogen removal through the anammox-mediated pathway. Functional gene analysis based on metagenomic sequencing confirmed that different compartments of the mABR were capable of performing distinct functions with specific advantageous microbial groups, facilitating targeted nutrient removal. Additionally, under oligotrophic conditions, the activity of the anammox bacteria-related genes of hzs was higher compared to that of hdh. Thus, an innovative method for the treatment of low-strength municipal and nitrate-containing wastewaters without aeration was presented, mediated by an anammox process with less land area and excellent quality effluent.
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Reatores Biológicos , Carbono , Desnitrificação , Nitrogênio , Fósforo , Fósforo/metabolismo , Nitrogênio/metabolismo , Carbono/metabolismo , Bactérias/metabolismoRESUMO
Since the mass production and extensive use of chloroquine (CLQ) would lead to its inevitable discharge, wastewater treatment plants (WWTPs) might play a key role in the management of CLQ. Despite the reported functional versatility of ammonia-oxidizing bacteria (AOB) that mediate the first step for biological nitrogen removal at WWTP (i.e., partial nitrification), their potential capability to degrade CLQ remains to be discovered. Therefore, with the enriched partial nitrification sludge, a series of dedicated batch tests were performed in this study to verify the performance and mechanisms of CLQ biodegradation under the ammonium conditions of mainstream wastewater. The results showed that AOB could degrade CLQ in the presence of ammonium oxidation activity, but the capability was limited by the amount of partial nitrification sludge (â¼1.1 mg/L at a mixed liquor volatile suspended solids concentration of 200 mg/L). CLQ and its biodegradation products were found to have no significant effect on the ammonium oxidation activity of AOB while the latter would promote N2O production through the AOB denitrification pathway, especially at relatively low DO levels (≤0.5 mg-O2/L). This study provided valuable insights into a more comprehensive assessment of the fate of CLQ in the context of wastewater treatment.
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Amônia , Compostos de Amônio , Amônia/metabolismo , Esgotos/microbiologia , Bactérias/metabolismo , Reatores Biológicos/microbiologia , Oxirredução , Óxido Nitroso/análise , Nitrificação , Compostos de Amônio/metabolismoRESUMO
Nucleosome positioning is critical to chromatin accessibility and is associated with gene expression programs in cells1-3. Previous nucleosome mapping methods assemble profiles from cell populations and reveal a cell-averaged pattern: nucleosomes are positioned and form a phased array that surrounds the transcription start sites of active genes3-6 and DNase I hypersensitive sites7. However, even in a homogenous population of cells, cells exhibit heterogeneity in expression in response to active signalling8,9 that may be related to heterogeneity in chromatin accessibility10-12. Here we report a technique, termed single-cell micrococcal nuclease sequencing (scMNase-seq), that can be used to simultaneously measure genome-wide nucleosome positioning and chromatin accessibility in single cells. Application of scMNase-seq to NIH3T3 cells, mouse primary naive CD4 T cells and mouse embryonic stem cells reveals two principles of nucleosome organization: first, nucleosomes in heterochromatin regions, or that surround the transcription start sites of silent genes, show large variation in positioning across different cells but are highly uniformly spaced along the nucleosome array; and second, nucleosomes that surround the transcription start sites of active genes and DNase I hypersensitive sites show little variation in positioning across different cells but are relatively heterogeneously spaced along the nucleosome array. We found a bimodal distribution of nucleosome spacing at DNase I hypersensitive sites, which corresponds to inaccessible and accessible states and is associated with nucleosome variation and variation in accessibility across cells. Nucleosome variation is smaller within single cells than across cells, and smaller within the same cell type than across cell types. A large fraction of naive CD4 T cells and mouse embryonic stem cells shows depleted nucleosome occupancy at the de novo enhancers detected in their respective differentiated lineages, revealing the existence of cells primed for differentiation to specific lineages in undifferentiated cell populations.
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Eucromatina/metabolismo , Inativação Gênica , Heterocromatina/metabolismo , Nuclease do Micrococo/metabolismo , Nucleossomos/genética , Nucleossomos/metabolismo , Análise de Célula Única , Células 3T3 , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Diferenciação Celular/genética , Linhagem da Célula/genética , Células Cultivadas , Desoxirribonuclease I/metabolismo , Elementos Facilitadores Genéticos/genética , Eucromatina/genética , Genoma/genética , Heterocromatina/genética , Masculino , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Especificidade de Órgãos/genética , Sítio de Iniciação de TranscriçãoRESUMO
Change history: In Fig. 1c of this Letter, the two graphs were duplicates. The right panel of Fig. 1c has been corrected online.
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Out of the total cases of cervical cancer, brain metastases (BMs) are relatively rare, with an estimated incidence rate of 0.63% (range: 0.1%-2.2%). Additionally, BMs prognosis remains poor, and the average patient survival time following a BM diagnosis is 3 to 5 months. Few studies have addressed the effect of programmed cell death-1 inhibitors against BMs in cervical cancer, although they are an established option for recurrent/metastatic disease. Hence, we report a case involving a 54-year-old post-surgery patient with cervical cancer with a body mass index of 19.5 kg/m2 and Eastern Collaborative Oncology Group (ECOG) performance status of 3; the disease recurred with BMs 1 year later. Intensity-modulated radiation therapy concurrent with temozolomide and bevacizumab was initiated, following which zimberelimab immunotherapy combined with anlotinib was administered to extend tumor control. The patient had a progression-free survival duration of 10 months, the tumor response was assessed as a partial response based on the evaluation criteria for solid tumors (RECIST1.1), and the ECOG status improved to 1 after therapy. These findings suggest that immunotherapy-based combination therapy following radiotherapy may be a good choice for patients with cervical cancer and BMs.
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Neoplasias Encefálicas , Neoplasias do Colo do Útero , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/tratamento farmacológico , Recidiva Local de Neoplasia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Anticorpos Monoclonais Humanizados/uso terapêuticoRESUMO
Wastes recycling and reutilization technique could simultaneously fulfill waste control and energy recovery sustainably, which has attracted increasing attention. This work proposed a novel waste reuse technology utilizing ceramsite and amended Fe2O3-ceramsite made from waste activated sludge (WAS) as additives to promote the yield of methane from WAS anaerobic digestion (AD). Experimental results demonstrated that compared to the control (85.05 ± 0.2 mL CH4/g-VS), the cumulative methane yield was effectively enhanced by 14% and 40% when ceramsite and Fe2O3-ceramsite were added. Further investigation revealed that ceramsite, especially the Fe2O3-ceramsite, enriched the populations of key anaerobes involved in hydrolysis, acidification, and methanogenesis. Meanwhile, potential syntrophic metabolisms between syntrophic bacteria and methanogens were confirmed in the Fe2O3-ceramsite AD system. Mechanisms studies exhibited that ceramsite and Fe2O3-ceramsite reinforced intermediate processes for methane production. The favorable pore structure, enhanced Fe (III) reduction capacity and conductivity also contributed a lot to the AD process.
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Bactérias Anaeróbias , Misturas Complexas , Esgotos , Anaerobiose , Esgotos/química , Bactérias Anaeróbias/metabolismo , Metano , Reatores Biológicos , Eliminação de Resíduos Líquidos/métodosRESUMO
The practice of aquaculture is associated with the generation of a substantial quantity of effluent. Microalgae must effectively assimilate nitrogen and phosphorus from their surrounding environment for growth. This study modeled the algal biomass film, NO3-N concentration, and pH in the membrane bioreactor using the response surface methodology (RSM) and an artificial neural network (ANN). Furthermore, it was suggested that the optimal condition for each parameter be determined. The results of ANN modeling showed that ANN with a structure of 5-3 and employing the transfer functions tansig-logsig demonstrated the highest level of accuracy. This was evidenced by the obtained values of coefficient (R2) = 0.998, R = 0.999, mean squared error (MAE) = 0.0856, and mean square error (MSE) = 0.143. The ANN model, characterized by a 5-5 structure and employing the tansig-logsig transfer function, demonstrates superior accuracy when predicting the concentration of NO3-N and pH. This is evidenced by the high values of R2 (0.996), R (0.998), MAE (0.00162), and MSE (0.0262). The RSM was afterward employed to maximize the performance of algal film biomass, pH levels, and NO3-N concentrations. The optimal conditions for the algal biomass film were a concentration of 2.884 mg/L and a duration of 6.589 days. Similarly, the most favorable conditions for the NO3-N concentration and pH were 2.984 mg/L and 6.787 days, respectively. Therefore, this research uses non-dominated sorting genetic algorithm II (NSGA II) to find the optimal NO3-N concentration, algal biomass film, and pH for product or process quality. The region has the greatest alkaline pH and lowest NO3-N content.
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Dióxido de Carbono , Redes Neurais de Computação , Biomassa , Reatores Biológicos , Concentração de Íons de HidrogênioRESUMO
Anaerobic digestion (AD) is a promising technique for waste management, which can achieve sludge stabilization and energy recovery. This study successfully prepared Fe3O4@ceramsite from WAS and applied it as an additive in sludge digestion, aiming to improve the conversion of organics to biomethane efficiency. Results showed that after adding the Fe3O4@ceramsite, the methane production was enhanced by 34.7% compared with the control group (88.0 ± 0.1 mL/g VS). Further mechanisms investigation revealed that Fe3O4@ceramsite enhanced digesta stability by strong buffering capacity, improved sludge conductivity, and promoted Fe (III) reduction. Moreover, Fe3O4@ceramsite has a larger surface area and better porous structure, which also facilitated AD performance. Microbial community analysis showed that some functional anaerobes related to AD such as Spirochaeta and Smithella were enriched with Fe3O4@ceramsite treatment. Potential syntrophic metabolisms between syntrophic bacteria (Syntrophomonas, associated with DIET) and methanogens were also detected in the Fe3O4@ceramsite treatment AD system.
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Metano , Esgotos , Anaerobiose , Metano/metabolismo , Compostos Férricos , Eliminação de Resíduos Líquidos/métodosRESUMO
Heterotrophic-sulfur autotrophic denitrification (HAD) has been proposed to be a prospective nitrogen removal process. In this work, the potential of fermentation liquid (FL) from waste-activated sludge (WAS) as the electron donor for denitrification in the HAD system was explored and compared with other conventional carbon sources. Results showed that when FL was used as a carbon source, over 99% of NO3--N was removed and its removal rate exceeded 14.00 mg N/g MLSS/h, which was significantly higher than that of methanol and propionic acid. The produced sulfate was below the limit value and the emission of N2O was low (1.38% of the NO3--N). Microbial community analysis showed that autotrophic denitrifiers were predominated in the HAD system, in which Thiobacillus (16.4%) was the dominant genus. The economic analysis showed the cost of the FL was 0.062 /m3, which was 30% lower than that in the group dosed with methanol. Our results demonstrated the FL was a promising carbon source for the HAD system, which could reduce carbon emission and cost, and offer a creative approach for waste-activated sludge resource reuse.
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Carbono , Desnitrificação , Fermentação , Nitrogênio , Esgotos , Carbono/metabolismo , Nitrogênio/metabolismo , Eliminação de Resíduos Líquidos/métodosRESUMO
Dealing with the current defaults of environmental toxicity, heating, waste management, and economic crises, exploration of novel non-edible, toxic, and waste feedstock for renewable biodiesel synthesis is the need of the hour. The present study is concerned with Buxus papillosa with seeds oil concentration (45% w/w), a promising biodiesel feedstock encountering environmental defaults and waste management; in addition, this research performed simulation based-response surface methodology (RSM) for Buxus papillosa bio-diesel. Synthesis and application of novel Phyto-nanocatalyst bimetallic oxide with Buxus papillosa fruit capsule aqueous extract was advantageous during transesterification. Characterization of sodium/potassium oxide Phyto-nanocatalyst confirmed 23.5 nm nano-size and enhanced catalytic activity. Other characterizing tools are FTIR, DRS, XRD, Zeta potential, SEM, and EDX. Methyl ester formation was authenticated by FTIR, GC-MS, and NMR. A maximum 97% yield was obtained at optimized conditions i.e., methanol ratio to oil (8:1), catalyst amount (0.37 wt%), reaction duration (180 min), and temperature of 80 °C. The reusability of novel sodium/potassium oxide was checked for six reactions. Buxus papillosa fuel properties were within the international restrictions of fuel. The sulphur content of 0.00090% signified the environmental remedial nature of Buxus papillosa methyl esters and it is a highly recommendable species for biodiesel production at large scale due to a t huge number of seeds production and vast distribution.
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Buxus , Gerenciamento de Resíduos , Resíduos Perigosos , Biocombustíveis/análise , Ésteres , Catálise , Sódio , Óleos de PlantasRESUMO
Little is known about the association between coronavirus disease 2019 (COVID-19) and autoimmune diseases, especially in the case of systemic lupus erythematosus (SLE). SLE patients met with many questions during the pandemic in COVID-19, such as how to minimize risk of infection, the complex pathological features and cytokine profiles, diagnosis and treatment, rational choice of drugs and vaccine, good nursing, psychological supervision, and so on. In this study, we review and discuss the multifaceted effects of the COVID-19 pandemic on patients living with SLE using the available literature. Cross-talk in implicated inflammatory pathways/mechanisms exists between SLE and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and SARS-CoV-2 displays similar clinical characteristics and immuno-inflammatory responses to SLE. Current epidemiological data inadequately assess the risk and severity of COVID-19 infection in patients with SLE. More evidence has shown that hydroxychloroquine and chloroquine cannot prevent COVID-19. During the pandemic, patients with SLE had a higher rate of hospitalization. Vaccination helps to reduce the risk of infection. Several therapies for patients with SLE infected with COVID-19 are discussed. The cases in the study can provide meaningful information for clinical diagnosis and management. Our main aim is to help preventing infection and highlight treatment options for patients with SLE infected with COVID-19.
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COVID-19 , Lúpus Eritematoso Sistêmico , Humanos , COVID-19/epidemiologia , COVID-19/complicações , Pandemias/prevenção & controle , SARS-CoV-2 , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Hidroxicloroquina/uso terapêuticoRESUMO
Handedness is an essential attribute of chiral nanocrystals, having a major influence on their properties. During chemical growth, the handedness of nanocrystals is usually tuned by selecting the corresponding enantiomer of chiral molecules involved in asymmetric growth, often known as chiral inducers. We report that, even using the same chiral inducer enantiomer, the handedness of chiral gold nanocrystals can be reversed by using Au nanorod seeds with either single crystalline or pentatwinned structure. This effect holds for chiral growth induced both by amino acids and by chiral micelles. Although it was challenging to discern the morphological handedness for L-cystine-directed particles, even using electron tomography, both cases showed circular dichroism bands of opposite sign, with nearly mirrored chiroptical signatures for chiral micelle-directed growth, along with quasi-helical wrinkles of inverted handedness. These results expand the chiral growth toolbox with an effect that might be exploited to yield a host of interesting morphologies with tunable optical properties.
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The development of efficient photocatalysts for N2 fixation to produce NH3 under ambient conditions remains a great challenge. Since covalent organic frameworks (COFs) possess predesignable chemical structures, good crystallinity, and high porosity, it is highly significant to explore their potential for photocatalytic nitrogen conversion. Herein, we report a series of isostructural porphyrin-based COFs loaded with Au single atoms (COFX-Au, X = 1-5) for photocatalytic N2 fixation. The porphyrin building blocks act as the docking sites to immobilize Au single atoms as well as light-harvesting antennae. The microenvironment of the Au catalytic center is precisely tuned by controlling the functional groups at the proximal and distal positions of porphyrin units. As a result, COF1-Au decorated with strong electron-withdrawing groups exhibits a high activity toward NH3 production with rates of 333.0 ± 22.4 µmol g-1 h-1 and 37.0 ± 2.5 mmol gAu-1 h-1, which are 2.8- and 171-fold higher than that of COF4-Au decorated with electron-donating functional groups and a porphyrin-Au molecular catalyst, respectively. The NH3 production rates could be further increased to 427.9 ± 18.7 µmol g-1 h-1 and 61.1 ± 2.7 mmol gAu-1 h-1 under the catalysis of COF5-Au featuring two different kinds of strong electron-withdrawing groups. The structure-activity relationship analysis reveals that the introduction of electron-withdrawing groups facilitates the separation and transportation of photogenerated electrons within the entire framework. This work manifests that the structures and optoelectronic properties of COF-based photocatalysts can be finely tuned through a rational predesign at the molecular level, thus leading to superior NH3 evolution.
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Biominerals are unique materials found in many living organisms that often display outstanding functionalities attributed to their mesocrystalline structure. Mesocrystals are nanocrystal superstructures with mutual crystallographic alignment of the building units. One could thus imagine these optimized evolutionary systems as archetypes to fabricate advanced materials. The main advantage of such systems relies on their ability to combine the features of the nanocrystals with those of single crystalline microscopic structures, yielding assemblies with directional, enhanced, and potentially emergent properties. Moreover, fueled by the promises of multifunctional materials with unprecedented and tunable properties, the rational design of mesocrystals assembled from two distinct colloidal nanocrystal ensembles has become a recent focus of research. However, the combination of dissimilar nanocrystals into ordered binary superstructures is still a major scientific challenge due to the nature of the coassembly process.We focus this Account on the growth of tridimensional (3D) binary mesocrystals and the understanding of the self-assembly of two colloidal nanocrystal ensembles with the ultimate goal to serve as a basis for more rational mesocrystal syntheses in the future. The formation of mesocrystals demands nanocrystals with defined surface faceting, the primary factor influencing their oriented self-assembly. Notably, such a process cannot be successfully afforded without functionalized nanocrystals with high and, in many cases, tunable colloidal stability. Besides, the nature and solvation degree of the surface ligand shell influences the effective shape of the nanocrystals and the kinetics of self-assembly. If the assembly is triggered by reducing the colloidal stability with nonsolvents, 3D single-component mesocrystals are often grown. Here, the different magnitude of the van der Waals attraction forces between nanocrystals with differing compositions, dimensions, and morphologies generally favors the segregation and growth of single component mesocrystals. This phenomenon was illustrated during the successful preparation of 3D binary mesocrystals composed of iron oxide and platinum nanocubes. Although the building blocks possessed comparable sizes and were stabilized by similar ligands, the amount of the second component could only be arbitrarily tuned up to some extent, even when the assembly conditions were rationally optimized to achieve 3D binary mesocrystals. Only a small amount of it was effectively incorporated into the matrix of the initial mesocrystal. The 3D binary mesocrystal growth process demands a delicate control over the size, shape, and surface chemistry of the nanocrystals, the solvent nature, and the self-assembly process. Hence, the improvement of our ability to control the synthesis of 3D binary mesocrystalline materials is critical to exploit their potential toward technological applications in catalysis, energy storage, or structural materials.