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BACKGROUND/OBJECTIVES: As the most frequent functional pancreatic neuroendocrine tumor, insulinomas may cause a plethora of symptoms and severe impairment in the living of patients by endogenous hyperinsulinemia and subsequent hypoglycemia. Surgery has been regarded as the first choice although a high risk of complications. Ethanol ablation is a promising non-surgical option that could achieve tumor shrinking in a short-term period. But the impact of symptom control and the long-term efficacy lack sufficient and good-quality evidence. METHODS: A total number of 14 endoscopic ultrasonography-guided ethanol ablations were performed in 9 patients between September 2016 and September 2018 in Peking Union Medical College Hospital. The data were collected and prospectively analyzed. RESULTS: The follow-up duration ranged from 21 to 1567 days in 9 patients, with a median of 994 days. 4 patients were free from relapse during a median follow-up of 1108 days (range: 994-1567 days). In 5 patients who suffered relapses, the median duration with symptom relief after the first ablation was 128 days (range: 13-393 days). If only repeated ablation was taken into consideration, the median duration with symptom relief was 26 days (range: 1-516 days). No complications happened during the procedures. The severe complication rate after the first ablation was 0.0% (0/9), compared to 7.14% (1/14) if each procedure was counted separately. The only severe complication documented was acute pancreatitis which was completely relieved after symptomatic treatment. CONCLUSIONS: For patients who are not suitable for surgical resections, endoscopic ultrasonography-guided ethanol ablation of insulinomas could be an effective and safe alternative to relieve symptoms of hypoglycemia.
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Hipoglucemia , Insulinoma , Neoplasias Pancreáticas , Pancreatitis , Humanos , Insulinoma/diagnóstico por imagen , Insulinoma/cirugía , Etanol/uso terapéutico , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/cirugía , Neoplasias Pancreáticas/complicaciones , Endosonografía , Enfermedad Aguda , Resultado del Tratamiento , Pancreatitis/complicaciones , Recurrencia Local de Neoplasia , Hipoglucemia/etiologíaRESUMEN
With the increase of global demand for cash crops, a large of cash crop waste was produced and caused severe environmental issues. To produce Agricultural Jiaosu (AJ) using these wastes is a sustainable waste disposal method. However, the fermentation mechanism, metabolites, and microbial characteristics of AJ fermented with different substrates remain unclear. In this study, the effects of different substrates (fruit and vegetable waste and Chinese herbal medicine waste) on the fermentation characteristics of AJ, including metabolites and microbial community properties, were investigated. The results revealed that AJ fermentation was a process of converting organic matter into organic acids and other metabolites, mainly including hydrolysis, acidogenesis, and maturation stages. At the genus level, Lactobacillus, Acetobacter, Hydrogenibacillus, Halomonas, and Prevotella_1 were the dominant bacteria in the fermentation system. The bacterial diversity of composite substrate AJ was higher than that of single substrate AJ. The organic acids and secondary metabolites concentration and the composition of key microorganisms depended on the substrate type. Furthermore, AJ's potential functional genes were mainly concentrated in cofactors and vitamin, carbohydrate, and amino acid metabolism. The findings of this study indicated that AJ is an innovative eco-friendly technology that can convert cash crop wastes into sustainable eco-products, and that its characteristics depend on the substrate type. Therefore, the substrate used to produce AJ should be carefully selected according to the application field.
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Bacterias , Microbiota , Fermentación , Bacterias/genética , Bacterias/metabolismo , Agricultura , VerdurasRESUMEN
BACKGROUND AND AIMS: The differential diagnosis of immunoglobulin G4-related sclerosing cholangitis (IgG4-SC) and cholangiocarcinoma (CC) remains a clinical challenge. Imaging modalities play critical roles in the diagnosis of IgG4-SC. The present study aimed to evaluate the differential diagnosis of IgG4-SC and CC based on images of endoscopic ultrasound (EUS). METHODS: The biliary inflammation scoring (BIS) method for EUS was developed based on the comparison between images of IgG4-SC and that of cholangiocarcinoma (CC) and other acute or chronic cholangitis. In the BIS diagnostic phase, the EUS images from 66 IgG4-SC patients and 44 CC patients were blindly evaluated using the BIS methods. RESULTS: The sensitivity, specificity, and accuracy of the newly established BIS in distinguishing IgG4-SC from CC were 86% [95% confidence interval (CI) 75-93%], 95% (95% CI 83-99%), and 90% (95% CI 83-94%), respectively. CONCLUSION: EUS should be considered to be added to the workup algorithm in patients with suspected IgG4-SC as a useful diagnostic procedure. BIS is a promising diagnostic method to discriminate IgG4-SC during the ongoing endoscopy.
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Neoplasias de los Conductos Biliares , Colangitis Esclerosante , Neoplasias de los Conductos Biliares/diagnóstico por imagen , Conductos Biliares Intrahepáticos , Colangitis Esclerosante/diagnóstico por imagen , Diagnóstico Diferencial , Humanos , Inmunoglobulina G , InflamaciónRESUMEN
OBJECTIVE: To analyze the clinical value of the detection of serum desgamma carboxy prothrombin (DCP), golgi glycoprotein 73 (GP73), heat-shock protein 70 (HSP70) in primary hepatic carcinoma (PHC) diagnosis. METHODS: Enzyme-1inked immunosorbent assay and electrochemiluminescence immunoassay were used to detect the serum DCP, GP73, HSP70 and α-fetoprotein (AFP) levels in 35 PHC patients and 35 healthy controls. RESULTS: AFP, DCP and GP73 levels in PHC patients were 13.780 (1.140-8 487.000)µg/L, 3 213.953 (2.510-53 994.602)pg/ml and 76.838 (24.500-232.875)ng/ml respectively, significantly higher than those in healthy controls (1.240 (0.605-5.310)µg/L, 104.610 (0.000-4 138.770)pg/ml and 30.770 (16.343-87.453)ng/ml, U value were 134.50, 258.00 and 168.00, all P < 0.01); HSP70 could not be detected in any objects. The area under the ROC curve of DCP or GP73 was 0.789, 0.863 respectively. The sensitivity and specificity to PHC diagnosis were 54.3% and 97.1% by DCP (2 939.4 pg/ml as cut-off value), 85.7% and 74.3% by GP73 (41.3 ng/ml as cut-off value), 45.7% and 100% by AFP (20 µg/L as cut-off value). In combined detection the sensitivity, specificity and accuracy were 88.6%, 74.3%, 81.4% by GP73/AFP and 91.4%, 71.4%, 81.4% by GP73/DCP/AFP. CONCLUSION: GP73, DCP are new effective markers in the diagnosis of PHC, and the combined detection of GP73, DCP and AFP can improve the diagnosis value of PHC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Protrombina , Biomarcadores , Proteínas HSP70 de Choque Térmico , Hemostáticos , Humanos , Curva ROC , alfa-FetoproteínasAsunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Antineoplásicos/farmacología , Heces/química , Heces/microbiología , Jirafas/microbiología , Streptomyces/metabolismo , Animales , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Bacillus subtilis/efectos de los fármacos , Candida/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cryptococcus neoformans/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Jirafas/metabolismo , Humanos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacos , Streptomyces/aislamiento & purificaciónRESUMEN
Heat stress is one of the major abiotic stresses affecting the growth, sporulation, colonization and survival of Trichoderma viride. This study aimed to gain a better insight into the underlying mechanism governing the heat stress response of T. viride Tv-1511. We analysed the transcriptomic changes of Tv-1511 under normal and heat stress conditions using RNA sequencing. We observed that Tv-1511 regulates the biosynthesis of secondary metabolites through a complex network of signalling pathways. Additionally, it significantly activates the anti-oxidant defence system, heat shock proteins and stress-response-related transcription factors in response to heat stress. TvHSP70 was identified as a key gene, and transgenic Tv-1511 overexpressing TvHSP70 (TvHSP70-OE) was generated. We conducted an integrated morphological, physiological and molecular analyses of the TvHSP70-OE and wild-type strains. We observed that TvHSP70 over-expression significantly triggered the growth, anti-oxidant capacity, anti-fungal activity and growth-promoting ability of Tv-1511. Regarding anti-oxidant capacity, TvHSP70 primarily up-regulated genes involved in enzymatic and non-enzymatic anti-oxidant systems. In terms of anti-fungal activity, TvHSP70 primarily activated genes involved in the synthesis of enediyne, anti-fungal and aminoglycoside antibiotics. This study provides a comparative analysis of the functional significance and molecular mechanisms of HSP70 in Trichoderma. These findings provide a valuable foundation for further analyses.
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Introduction: Melatonin (N-acetyl-5-methoxytryptamine) is a molecule implicated in multiple biological functions, but exerts contrasting effects on plants owing to concentration differences. Hydroxyindole O-methyltransferase (HIOMT), which catalyzes the last step of melatonin synthesis, plays a crucial role in this context. Methods: Transgenic switchgrass overexpressing oHIOMT with different melatonin levels displayed distinct morphological changes in a concentration-dependent manner. In this study, we divided the transgenic switchgrass into two groups: melatonin-moderate transgenic (MMT) plants and melatonin-rich transgenic (MRT) plants. To determine the concentration-dependent effect of melatonin on switchgrass growth and stress resistance, we conducted comparative morphological, physiological, omics and molecular analyses between MMT, MRT and wild-type (WT) plants. Results: We found that oHIOMT overexpression, with moderate melatonin levels, was crucial in regulating switchgrass growth through changes in cell size rather than cell number. Moderate levels of melatonin were vital in regulating carbon fixation, stomatal development and chlorophyll metabolism. Regarding salt tolerance, melatonin with moderate levels activated numerous defense (e.g. morphological characteristics, anatomical structure, antioxidant enzymatic properties, non-enzymatic capacity and Na+/K+ homeostasis). Additionally, moderate levels of oHIOMT overexpression were sufficient to increase lignin content and alter monolignol compositions with an increase in the S/G lignin ratio. Discussion: Taken together, oHIOMT overexpression in switchgrass with different melatonin levels resulted in morphological, anatomical, physiological and molecular changes in a concentration-dependent manner, which characterized by stimulation at low doses and inhibition at high doses. Our study presents new ideas and clues for further research on the mechanisms of the concentration-dependent effect of melatonin.
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Anaerobic digestion (AD) of nitrogen-rich substrates often suffers from the issue of ammonia inhibition. Although bioaugmentation has been used to assist AD with high ammonia concentration, the combined effect of domesticated syntrophic consortium (MC) together with biochar on ammonia inhibited AD are still unknown. In the present study, MC was adapted and enriched by purposive domestication. As a novel strategy, coconut shell-derived biochar was used as a carrier to aid the MC. The results showed that the digestion system deteriorated completely without the assistance of MC and biochar when the TAN concentration exceeded 8.0 g L-1. The combination of biochar and MC (B-MC treatment) could restore ammonia inhibition in 10 days and achieved a high methane yield of 357.5 mL g-1 volatile solid, which was 7.5 % higher than that of MC treatment. Syntrophomonas, Syntrophobacter, and Methanoculleus in MC played a critical role in reducing propionic acid and butyric acid content and efficiently producing methane. Their abundances increased 12-fold, 10-fold, and 2-fold, respectively. With the assistance of biochar, MC had a better performance in relieving ammonia inhibition. This could be attributed to two aspects. First, biochar encouraged the growth or colonization of key microorganisms such as propionate and butyrate oxidizing bacteria and ammonia-tolerant archaea. Second, biochar induced the growth of conductive microorganisms such as Geobacter. From the perspective of enzyme genes, biochar increased the abundance of related enzyme genes in butyrate and propionate degradation, acetoclastic and hydrogenotrophic pathways. In conclusion, MC combined with biochar is a potential approach to alleviate ammonia nitrogen inhibition.
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Amoníaco , Propionatos , Anaerobiosis , Amoníaco/metabolismo , Cocos , Metano , Reactores Biológicos/microbiología , Ácido Butírico , NitrógenoRESUMEN
Ammonia inhibition is a challenging issue in the anaerobic digestion (AD) of nitrogen-rich substrates and hinders the energy recovery from organic wastes. Bioaugmentation is promising strategy to stabilize AD systems with high ammonia concentration. The composition of microbial consortia often determines their effectiveness in bioaugmentation. Up to now, the effect of various microbial consortia as biological additives on the AD systems is not fully understood. In this study, two microbial consortia (syntrophic microbial consortium, MC, and hydrogenotrophic methanogen consortium, SS) were obtained through two domestication methods, and were applied in a nitrogen-rich AD system. The results showed that the MC and SS treatments could restore AD performance within 21 days and 83 days, respectively. The recovery of digestion performance depended on the methanogenic archaea Methanospirillum, Methanothermobacter, and Methanoculleus in the early and later stages. Analysis of the 13C isotope indicated that both MC and SS enhanced the hydrogenotrophic pathway. The KEGG analysis showed that the MC not only promoted the key enzyme genes in the hydrogenotrophic pathway but also had a positive effect on the related enzyme genes of propionate and butyrate degradation, which was affected by the abundant short-chain fatty acids degrading bacteria, such as Syntrophomonas, Syntrophobacter, and Tissierella in the MC. After recovery of digestion performance, there was no significant difference (p > 0.05) in methane yield between the MS and SS treatments. Therefore, the best intervention period for bioaugmentation is when the digestion performance of the AD system is unstable.
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Euryarchaeota , Consorcios Microbianos , Reactores Biológicos/microbiología , Anaerobiosis , Amoníaco , Metano , Aclimatación , NitrógenoRESUMEN
Indigenous soil microbial biomass (ISMB) plays a key role in maintaining essential functions and biodiversity of soil health. One of the critical unknowns is how the indigenous microorganisms respond to different fertilizers which is directly related to agricultural production. Therefore, we used Mi-Seq sequencing and network analyses to compare the response of ISMB to biogas residue and chemical fertilizers. The results showed that crop production was profoundly influenced by levels of ISMB present and is further dependent on the strategy of fertilizer application. Higher ISMB primarily manifests through retention of richer microbial abundance, a balanced community structure, and tightened co-occurrence within a certain proportion of Nitrospirae, Rhizophlyctidaceae, and Gemmatimonadetes. Compared to chemical fertilizer, biogas residue resulted in higher production with more strongly linked nodes such as Actinobacteria, Chloroflexi and Gemmatimonadetes. Under the same level of ISMB, the microbial diversity was richer and co-occurrence was tighter when biogas residues were applied compared with chemical fertilizer. In addition, the higher level of ISMB with biogas residue applied had a lower abundance of potential fungal pathogens in both bulk and rhizosphere soil compared with chemical fertilizer. This study provides critical data to understand the influence of ISMB and biogas residue on soil ecological system.
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Excessive or insufficient supplementation of trace elements (TEs) limits the progression of anaerobic digestion. The main reason for this is the lack of sufficient understanding of digestion substrate characteristics, which significantly affects the demand for TEs. In this review, the relationship between TEs requirements and substrate characteristics is discussed. We mainly focus on three aspects. 1) The basis for TE optimization and existing problems: The optimization of TEs often based on the total solids (TS) or volatile solids (VS) of substrates, does not fully consider substrate characteristics. 2) TE deficiency mechanisms for different types of substrates: nitrogen-rich, sulfur-rich, TE-poor, and easily hydrolyzed substrates are the four main types of substrates. The mechanisms underlying TEs deficiency in the different substrates are investigated. 3) Regulation of TE bioavailability: characteristics of substrates affect digestion parameters, which disturb the bioavailability TE. Therefore, methods for regulating bioavailability of TEs are discussed.
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Oligoelementos , Oligoelementos/análisis , Residuos Sólidos , Anaerobiosis , Reactores Biológicos , MetanoRESUMEN
The rhizosphere microbiota plays a critical and crucial role in plant health and growth, assisting plants in resisting adverse stresses, including soil salinity. Plastic film mulching is an important method to adjust soil properties and improve crop yield, especially in saline-alkali soil. However, it remains unclear whether and to what extent the association between these improvements and rhizosphere microbiota exists. Here, from a field survey and a greenhouse mesocosm experiment, we found that mulching plastic films on saline-alkali soil can promote the growth of soybeans in the field. Results of the greenhouse experiment showed that soybeans grew better in unsterilized saline-alkali soil than in sterilized saline-alkali soil under plastic film mulching. By detecting the variations in soil properties and analyzing the high-throughput sequencing data, we found that with the effect of film mulching, soil moisture content was effectively maintained, soil salinity was obviously reduced, and rhizosphere bacterial and fungal communities were significantly changed. Ulteriorly, correlation analysis methods were applied. The optimization of soil properties ameliorated the survival conditions of soil microbes and promoted the increase in relative abundance of potential beneficial microorganisms, contributing to the growth of soybeans. Furthermore, the classification of potential key rhizosphere microbial OTUs were identified. In summary, our study suggests the important influence of soil properties as drivers on the alteration of rhizosphere microbial communities and indicates the important role of rhizosphere microbiota in promoting plant performance in saline-alkali soil under plastic film mulching.
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Anaerobic digestion of common rural wastes (human feces (HF), food waste (FW) and lawn grass (LG)) were studied considering the specific methane yield, process parameters and microbial characteristics (mainly microbial community and pathogenic bacteria). The results showed that co-digestion of multiple substrates obtained high digestion performance when the total solid (TS) was 4%. The optimal co-digestion ratio of HF, FW, and LG was 33-56%, 21-38% and 20-40%, respectively. The digestion system containing HF underwent ammonia inhibition, which leads to the succession of the methanogenesis pathway from the acetoclastic pathway to the hydrogenotrophic pathway. Simultaneously, the dominant methanogenic archaea changed from Methanosaeta to Methanobacterium and Methanosarcina. Co-digestion reduced Salmonella's absolute concentration. The recovered energy and nitrogen could meet 52-109 % energy demand of rural community and all nitrogen demand in lawn fertilization, respectively. The main rural organic wastes could be recycled by anaerobic digestion, considering the flexibility of substrate ratio.
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Reactores Biológicos , Eliminación de Residuos , Anaerobiosis , Alimentos , Humanos , Metano , MethanosarcinaRESUMEN
It is currently unclear whether trace elements (TEs) deficiency is due to low bioavailability or low absolute TEs concentrations, especially in high-pH anaerobic digestion (AD) systems. A mixed solution of TEs and EDTA-Na2 were used separately in mono-AD of chicken manure (CM) leachate to investigate this research gap. The results showed relatively low bioavailability of Fe, Mn, and Zn. The bioavailability of all TEs remained stable along with a gradual increase in total ammonia nitrogen concentration. Both TE and EDTA-Na2 supplementation improved the bioavailability of TEs, but TEs supplementation also gave a high proportion of soluble TEs. Adding TEs improved methane production efficiency (+38.3%) and decreased the H2S content. The exchangeable fraction of specific TE (Mo) in H2/CO2 pathway was higher in the TEs treatment. TEs bioavailability and absolute concentrations of available TEs are critical aspects that need to be scrutinized to assess the risk of TEs deficiency.
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Estiércol , Oligoelementos , Anaerobiosis , Animales , Disponibilidad Biológica , Reactores Biológicos , Pollos , MetanoRESUMEN
Root rot caused by the pathogenic fungi of the Fusarium genus poses a great threat to the yield and quality of medicinal plants. The application of Agricultural Jiaosu (AJ), which contains beneficial microbes and metabolites, represents a promising disease control strategy. However, the action-effect of AJ on Fusarium root rot disease remains unclear. In the present study, we evaluated the characteristics and antifungal activity of AJ fermented using waste leaves and stems of medicinal plants, and elucidated the mechanisms of AJ action by quantitative real-time PCR and redundancy analysis. The effects of AJ and antagonistic microbes isolated from it on disease suppression were further validated through a pot experiment. Our results indicate that the AJ was rich in beneficial microorganisms (Bacillus, Pseudomonas, and Lactobacillus), organic acids (acetic, formic, and butyric acids) and volatile organic compounds (alcohols and esters). It could effectively inhibit Fusarium oxysporum and the half-maximal inhibitory concentration (IC50) was 13.64%. The antifungal contribution rate of the microbial components of AJ reached 46.48%. Notably, the redundancy analysis revealed that the Bacillus and Pseudomonas genera occupied the main niche during the whole inhibition process. Moreover, the abundance of the Bacillus, Pseudomonas, and Lactobacillus genera were positively correlated with the pH-value, lactic, formic and butyric acids. The results showed that the combined effects of beneficial microbes and organic acid metabolites increased the efficacy of the AJ antifungal activity. The isolation and identification of AJ's antagonistic microbes detected 47 isolates that exhibited antagonistic activities against F. oxysporum in vitro. In particular, Bacillus subtilis and Bacillus velezensis presented the strongest antifungal activity. In the pot experiment, the application of AJ and these two Bacillus species significantly reduced the disease incidence of Fusarium root rot and promoted the growth of Astragalus. The present study provides a cost-effective method to control of Fusarium root rot disease, and establishes a whole-plant recycling pattern to promote the sustainable development of medicinal plant cultivation.
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Arylalkylamine N-acetyltransferase (AANAT) catalyses the acetylation of serotonin, a rate-limiting process in melatonin biosynthesis. To obtain better insight into the underlying mechanism of AANAT's actions in switchgrass growth, flowering and defence, we performed integrated morphological, physiological and omics analyses between overexpressed oAANAT transgenic lines in wild-type and transgenic control (expressing only the empty vector) plants. We showed that oAANAT played pivotal roles in modulating plant growth through its regulation of cell elongation, and regulating flowering through photoperiod and GA pathways. In relation to photosynthesis, oAANAT promoted photosynthetic efficiency primarily through regulating leaf anatomical structures, stomatal development and chlorophyll metabolism. Moreover, oAANAT overexpression can trigger a number of defence responses or strategies, including antioxidant enzymatic properties, non-enzymatic capacity, significantly activated phenylpropanoid biosynthesis, and adaptive morphological characteristics. This study unveils the possible molecular mechanisms underlying oAANAT dependent melatonin functions in switchgrass, providing an important starting point for further analyses.
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Melatonina , Panicum , N-Acetiltransferasa de Arilalquilamina , Panicum/genética , Hojas de la Planta/genética , Plantas Modificadas GenéticamenteRESUMEN
Anaerobic digestion (AD) is used to treat waste and produce bioenergy. However, toxicants, which originate from the substrate, can inhibit or damage the digestion process. Methanogenic archaea (MA), which are the executor in the methanogenesis stage, are more sensitive than bacteria to these toxicants. This review discusses the effects of substrate-driven toxicants, namely, antibiotics, H2S and sulfate, heavy metals (HMs), long-chain fatty acids (LCFAs), and ammonia nitrogen, on the activity of MAs, methanogenic pathways, and the inter-genus succession of MAs. The adverse effects of these five toxicants on MA include effects on pH, damages to cell membranes, the prevention of protein synthesis, changes in hydrogen partial pressure, a reduction in the bioavailability of trace elements, and hindrance of mass transfer. These effects cause a reduction in MA activity and the succession of MAs and methanogenic pathways, which affect AD performance. Under the stress of these toxicants, succession occurs among HA (hydrogenotrophic methanogen), AA (acetoclastic methanogen), and MM (methylotrophic methanogen), especially HA gradually replaces AA as the dominant MA. Simultaneously, the dominant methanogenic pathway also changes from the aceticlastic pathway to other methanogenic pathways. A comprehensive understanding of the impact of toxicants on MA permits more specific targeting when developing strategies to mitigate or eliminate the effects of these toxicants.
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Archaea , Reactores Biológicos , Amoníaco , Anaerobiosis , Archaea/genética , MetanoRESUMEN
Ammonia inhibition is the most challenging issue in the anaerobic digestion (AD) of nitrogen-rich substrates. Total ammonia nitrogen (TAN) concentration, temperature and pH are the main operational parameters affecting the chemical equilibrium between free ammonium nitrogen (NH3; FAN) and ammonium ions (NH4+). However, it is still unclear how these parameters together affect digestion performance by influencing this equilibrium. To determine the effect and linkages of these parameters, a Box-Behnken design-response surface methodology (RSM), correlation analysis and two kinetic models were carried out. The results revealed that the linear effect of TAN, the interaction effect between TAN and temperature, and temperature and pH were significant, however, the quadratic effect of TAN, temperature and pH were also significant. Furthermore, TAN and temperature were positively correlated with Mmax, k and Rmax. Findings from this study could provide a theoretical basis to develop the way of relieving ammonia inhibition.
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Amoníaco , Estiércol , Amoníaco/análisis , Anaerobiosis , Animales , Reactores Biológicos , Pollos , Concentración de Iones de Hidrógeno , Metano , Nitrógeno , TemperaturaRESUMEN
The carbon/nitrogen ratio (C/N) is a key parameter that affects the performance of anaerobic digestion (AD). Recent AD research has focused on optimizing the C/N of feedstock. The so-called "inhibited steady-state" refers to a special state of ammonia inhibition of AD that often occurs at low-C/N (below 25) when degradable nitrogen-rich substrates, such as livestock manure, are used as feedstock. However, the mechanism behind the "inhibited steady-state" is still unknown. In the current study, co-digestion and recirculation were used to create a C/N gradient in the influent to explore the relationship between substrates, metabolites, and microorganisms in the "inhibited steady-state." Data were collected at the macro, microbial, and genetic levels. Three CSTRs were successfully made run into the "inhibited steady-state" using influent C/Ns of 10-12. Digestion performance levels of R10-R12 were low and stable, transitioning from an aceticlastic methane-producing pathway to a hydrogenotrophic pathway as the C/N gradually decreased. As the abundance of the hydrogenophilic methanogens increased, the abundance of syntrophic acetate-oxidizing bacteria (SAOB) also increased. The succession between populations of Methanosaeta and Methanosarcina may be used as a microbiological indicator of ammonia inhibition. Under high-C/Ns, cooperation among bacteria was high, while under low-C/Ns, competition among bacteria was high. These results clarify the processes underlying the "inhibited steady-state," which is a condition often faced in actual large-scale biogas facilities that use degradable nitrogen-rich substrates. Moreover, practical guidelines for evaluating ammonia inhibition are provided, and strategies to alleviate ammonia suppression are developed.
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Reactores Biológicos , Nitrógeno , Amoníaco , Anaerobiosis , Biocombustibles , Carbono , MetanoRESUMEN
Objectives: The clinical outcome of bullous pemphigoid appears worse in patients with infectious complications, and assessment of the prevalence and risk factors of infectious complications could be necessary to plan preventative strategies and to instruct the treatment plans. We sought to determine the risk factors of infection and compare associated factors in inpatients and outpatients with different system infections. Design: This is a single-centered retrospective study on the medical records of 252 patients from 2010 to 2018 at the dermatology department, Peking Union Medical College. Medical profiles of medical history, diagnosis, infectious complications, and treatment plans were analyzed. The associated factors were compared between the subgroups, including inpatients and outpatients, different body sites of infection. Results: Of the total 252 patients with bullous pemphigoid (BP), 81 patients (81/252, 32.1%) had infectious complications. Forty-eight patients died from pulmonary infections (11/48, 22.9%), cardiovascular diseases (6/48, 12.5%), and other diseases. Infections were most frequently found in skin/mucosa (44/252, 17.5%), respiratory system (32/252, 12.7%), and blood (10/252, 4.0%). On multivariate analysis, risk factors of infections in BP were maximal control dose of corticosteroids (OR 2.539, 95% CI 1.456-4.430, p = 0.001), low serum albumin level (OR 2.557, 95% CI 1.283, 5.092, p = 0.007), hospitalization (OR 4.025, 95% CI 2.289, 7.079, p < 0.001), comorbidities including respiratory disease (OR 4.060, 95% CI, 1.861, 8.858, p < 0.001), eye disease (OR 4.431, 95% CI 1.864, 10.532, p < 0.001), and diabetes (OR 2.667, 95% CI 1.437, 4.949, p = 0.002). The rate of infection was significantly higher in inpatients compared to that in outpatients (54.0 vs. 20.6%, p < 0.001), with diverse risk factors. Mucocutaneous infections were associated with a maximal control dose of corticosteroid and other dermatoses. Respiratory infections were related to respiratory disease and old age, and hematologic infection was associated with low serum hemoglobin levels and mucosal involvement of BP. Both of them were associated with mucosal involvement of BP and high titer anti-BP180 antibody. Conclusions: Infectious complications of bullous pemphigoid are common and are associated with mucosal involvement of BP, more comorbidities, the higher dose of corticosteroids, and the lower level of serum albumin.