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1.
J Environ Sci (China) ; 146: 3-14, 2024 Dec.
Article de Anglais | MEDLINE | ID: mdl-38969459

RÉSUMÉ

Bacillus velezensis M3-1 strain isolated from the sediment of Myriophyllum aquatium constructed wetlands was found to efficiently convert NO3--N to NO2--N, and the requirements for carbon source addition were not very rigorous. This work demonstrates, for the first time, the feasibility of using the synergy of anammox and Bacillus velezensis M3-1 microorganisms for nitrogen removal. In this study, the possibility of M3-1 that converted NO3--N produced by anammox to NO2--N was verified in an anaerobic reactor. The NO3--N reduction ability of M3-1 and denitrifying bacteria in coupling system was investigated under different C/N conditions, and it was found that M3-1 used carbon sources preferentially over denitrifying bacteria. By adjusting the ratio of NH4+-N to NO2--N, it was found that the NO2--N converted from NO3--N by M3-1 participated in the original anammox.The nitrogen removal efficacy (NRE) of the coupled system was increased by 12.1%, compared to the control group anammox system at C/N = 2:1. Functional gene indicated that it might be a nitrate reducing bacterium.This study shows that the nitrate reduction rate achieved by the Bacillus velezensis M3-1 can be high enough for removing nitrate produced by anammox process, which would enable improve nitrogen removal from wastewater.


Sujet(s)
Ammoniac , Bacillus , Nitrates , Azote , Oxydoréduction , Bacillus/métabolisme , Azote/métabolisme , Nitrates/métabolisme , Ammoniac/métabolisme , Anaérobiose , Élimination des déchets liquides/méthodes , Dénitrification
2.
Sci Rep ; 14(1): 15080, 2024 07 02.
Article de Anglais | MEDLINE | ID: mdl-38956280

RÉSUMÉ

Plyometric training is characterized by high-intensity exercise which is performed in short term efforts divided into sets. The purpose of the present study was twofold: first, to investigate the effects of three distinct plyometric exercise protocols, each with varying work-to-rest ratios, on muscle fatigue and recovery using an incline-plane training machine; and second, to assess the relationship between changes in lower limb muscle strength and power and the biochemical response to the three exercise variants employed. Forty-five adult males were randomly divided into 3 groups (n = 15) performing an exercise of 60 rebounds on an incline-plane training machine. The G0 group performed continuous exercise, while the G45 and G90 groups completed 4 sets of 15 repetitions, each set lasting 45 s with 45 s rest in G45 (work-to-rest ratio of 1:1) and 90 s rest in G90 (1:2 ratio). Changes in muscle torques of knee extensors and flexors, as well as blood lactate (LA) and ammonia levels, were assessed before and every 5 min for 30 min after completing the workout. The results showed significantly higher (p < 0.001) average power across all jumps generated during intermittent compared to continuous exercise. The greatest decrease in knee extensor strength immediately post-exercise was recorded in group G0 and the least in G90. The post-exercise time course of LA changes followed a similar pattern in all groups, while the longer the interval between sets, the faster LA returned to baseline. Intermittent exercise had a more favourable effect on muscle energy metabolism and recovery than continuous exercise, and the work-to-rest ratio of 1:2 in plyometric exercises was sufficient rest time to allow the continuation of exercise in subsequent sets at similar intensity.


Sujet(s)
Fatigue musculaire , Force musculaire , Exercice de pliométrie , Repos , Humains , Mâle , Repos/physiologie , Fatigue musculaire/physiologie , Adulte , Force musculaire/physiologie , Exercice de pliométrie/méthodes , Jeune adulte , Muscles squelettiques/physiologie , Acide lactique/sang , Ammoniac/sang , Exercice physique/physiologie
3.
J Nippon Med Sch ; 91(3): 277-284, 2024.
Article de Anglais | MEDLINE | ID: mdl-38972740

RÉSUMÉ

BACKGROUND: Although occlusion of the right coronary artery (RCA) is common in the remote stages of Kawasaki disease, revascularization of the RCA is challenging in children and is usually managed by observation without intervention. METHODS: Using adenosine-stress 13N-ammonia myocardial perfusion positron emission tomography, we evaluated coronary circulation in 14 patients (12 males) with RCA occlusion to identify ischemia (myocardial flow ratio < 2.0) in the RCA region and examined hemodynamics, cardiac function, and coronary aneurysm diameter. These variables were also compared in patients with/without RCA segmental stenosis (SS). RESULTS: There were five cases of ischemia in the RCA region. RCA myocardial blood flow (MBF) at rest was higher in patients with ischemia than in those without ischemia, but the difference was not significant (1.27 ± 0.21 vs. 0.82 ± 0.16 mL/min/g, p = 0.2053). Nine patients presented with RCA SS, and age at onset of Kawasaki disease tended to be lower in those with SS. The maximum aneurysm diameter of RCA was significantly smaller in patients with SS (10.0 ± 2.8 vs. 14.7 ± 1.6, p = 0.0239). No significant differences in other variables were observed between patients with/without ischemia and SS. CONCLUSIONS: At rest, MBF in the RCA region was relatively well preserved, even in patients with RCA occlusion, and there was no progressive deterioration in cardiac function. Adenosine stress showed microcirculatory disturbances in only half of the patients, indicating that it is reversible in children with Kawasaki disease.


Sujet(s)
Ammoniac , Circulation coronarienne , Maladie de Kawasaki , Imagerie de perfusion myocardique , Radio-isotopes de l'azote , Tomographie par émission de positons , Humains , Maladie de Kawasaki/complications , Maladie de Kawasaki/physiopathologie , Maladie de Kawasaki/imagerie diagnostique , Mâle , Femelle , Ammoniac/sang , Tomographie par émission de positons/méthodes , Enfant , Enfant d'âge préscolaire , Imagerie de perfusion myocardique/méthodes , Occlusion coronarienne/étiologie , Occlusion coronarienne/imagerie diagnostique , Occlusion coronarienne/physiopathologie , Anévrysme coronarien/étiologie , Anévrysme coronarien/imagerie diagnostique , Anévrysme coronarien/physiopathologie , Adolescent , Nourrisson , Hémodynamique
4.
Sci Rep ; 14(1): 14848, 2024 06 27.
Article de Anglais | MEDLINE | ID: mdl-38937539

RÉSUMÉ

This study aimed to assess the safety and efficacy of interventional embolization in cirrhotic patients with refractory hepatic encephalopathy (HE) associated with large spontaneous portosystemic shunts (SPSS). Inverse probability of treatment weighting (IPTW) was employed to minimize potential bias. A total of 123 patients were included in this study (34 in the embolization group and 89 in the control group). In the unadjusted cohort, the embolization group demonstrated significantly better liver function, a larger total area of SPSS, and a higher percentage of patients with serum ammonia levels > 60 µmol/L and the presence of hepatocellular carcinoma (HCC) (all P < 0.05). In the IPTW cohort, baseline characteristics were comparable between the two groups (all P > 0.05). Patients in the embolization group exhibited significantly longer HE-free survival compared to the control group in both the unadjusted and IPTW cohorts (both P < 0.05). Subsequent subgroup analyses indicated that patients with serum ammonia level > 60 µmol/L, hepatopetal flow within the portal trunk, the presence of solitary SPSS, a baseline HE grade of II, and the absence of HCC at baseline showed statistically significant benefit from embolization treatment (all P < 0.05). No early procedural complications were observed in the embolization group. The incidence of long-term postoperative complications was comparable to that in the control group (all P > 0.05). Hence, interventional embolization appears to be a safe and effective treatment modality for cirrhotic patients with refractory HE associated with large SPSS. However, the benefits of embolization were discernible only in a specific subset of patients.


Sujet(s)
Embolisation thérapeutique , Encéphalopathie hépatique , Cirrhose du foie , Humains , Encéphalopathie hépatique/thérapie , Encéphalopathie hépatique/étiologie , Mâle , Femelle , Embolisation thérapeutique/méthodes , Adulte d'âge moyen , Cirrhose du foie/complications , Cirrhose du foie/thérapie , Sujet âgé , Résultat thérapeutique , Tumeurs du foie/thérapie , Tumeurs du foie/complications , Carcinome hépatocellulaire/thérapie , Carcinome hépatocellulaire/complications , Études rétrospectives , Ammoniac/sang
6.
J Zhejiang Univ Sci B ; 25(6): 485-498, 2024 May 15.
Article de Anglais, Chinois | MEDLINE | ID: mdl-38910494

RÉSUMÉ

End-stage liver diseases, such as cirrhosis and liver cancer caused by hepatitis B, are often combined with hepatic encephalopathy (HE); ammonia poisoning is posited as one of its main pathogenesis mechanisms. Ammonia is closely related to autophagy, but the molecular mechanism of ammonia's regulatory effect on autophagy in HE remains unclear. Sialylation is an essential form of glycosylation. In the nervous system, abnormal sialylation affects various physiological processes, such as neural development and synapse formation. ST3 ß|-galactoside α2,|3-sialyltransferase 6 (ST3GAL6) is one of the significant glycosyltransferases responsible for adding α2,3-linked sialic acid to substrates and generating glycan structures. We found that the expression of ST3GAL6 was upregulated in the brains of mice with HE and in astrocytes after ammonia induction, and the expression levels of α2,3-sialylated glycans and autophagy-related proteins microtubule-associated protein light chain 3 (LC3) and Beclin-1 were upregulated in ammonia-induced astrocytes. These findings suggest that ST3GAL6 is related to autophagy in HE. Therefore, we aimed to determine the regulatory relationship between ST3GAL6 and autophagy. We found that silencing ST3GAL6 and blocking or degrading α2,3-sialylated glycans by way of Maackia amurensis lectin-II (MAL-II) and neuraminidase can inhibit autophagy. In addition, silencing the expression of ST3GAL6 can downregulate the expression of heat shock protein ß8 (HSPB8) and Bcl2-associated athanogene 3 (BAG3). Notably, the overexpression of HSPB8 partially restored the reduced autophagy levels caused by silencing ST3GAL6 expression. Our results indicate that ST3GAL6 regulates autophagy through the HSPB8-BAG3 complex.


Sujet(s)
Protéines régulatrices de l'apoptose , Autophagie , Encéphale , Encéphalopathie hépatique , Polyosides , Sialyltransferases , Sialyltransferases/métabolisme , Sialyltransferases/génétique , Animaux , Souris , Polyosides/métabolisme , Encéphalopathie hépatique/métabolisme , Protéines régulatrices de l'apoptose/métabolisme , Encéphale/métabolisme , Protéines adaptatrices de la transduction du signal/métabolisme , Protéines adaptatrices de la transduction du signal/génétique , Ammoniac/métabolisme , Astrocytes/métabolisme , Mâle , , Chaperons moléculaires/métabolisme , Protéines du choc thermique/métabolisme , Humains , Extinction de l'expression des gènes , Protéines associées aux microtubules/métabolisme , Souris de lignée C57BL
7.
Clin Transl Gastroenterol ; 15(6): e1, 2024 Jun 01.
Article de Anglais | MEDLINE | ID: mdl-38916234

RÉSUMÉ

High-protein diet is the cornerstone of supportive care for patients living with hepatic encephalopathy. Although any protein source is better than protein restriction, there is uncertainty regarding the benefits of specific protein types. Using a randomized trial, Badal et al. evaluate the effect on ammonia levels and metabolomics from 3 protein sources in burgers made from beef, vegan products, and vegetarian products. The vegan and vegetarian burgers did not raise ammonia and may result in favorable metabolomic profiles.


Sujet(s)
Ammoniac , Régime végétalien , Régime végétarien , Encéphalopathie hépatique , Humains , Encéphalopathie hépatique/diétothérapie , Encéphalopathie hépatique/étiologie , Régime végétarien/effets indésirables , Régime végétalien/effets indésirables , Ammoniac/métabolisme , Protéines alimentaires/administration et posologie , Essais contrôlés randomisés comme sujet , Encéphale/métabolisme , Régime riche en protéines/effets indésirables , Métabolomique
8.
J Phys Chem B ; 128(24): 5840-5845, 2024 Jun 20.
Article de Anglais | MEDLINE | ID: mdl-38850249

RÉSUMÉ

Particulate MMO (pMMO) catalyzes the oxidation of methane to methanol and also ammonia to hydroxylamine. Experimental characterization of the active site has been very difficult partly because the enzyme is membrane-bound. However, recently, there has been major progress mainly through the use of cryogenic electron microscopy (cryoEM). Electron paramagnetic resonance (EPR) and X-ray spectroscopy have also been employed. Surprisingly, the active site has only one copper. There are two histidine ligands and one asparagine ligand, and the active site is surrounded by phenyl alanines but no charged amino acids in the close surrounding. The present study is the first quantum chemical study using a model of that active site (CuD). Low barrier mechanisms have been found, where an important part is that there are two initial proton-coupled electron transfer steps to a bound O2 ligand before the substrate enters. Surprisingly, this leads to large radical character for the oxygens even though they are protonated. That result is very important for the ability to accept a proton from the substrates. Methods have been used which have been thoroughly tested for redox enzyme mechanisms.


Sujet(s)
Ammoniac , Méthane , Oxydoréduction , Oxygénases , Méthane/composition chimique , Méthane/métabolisme , Oxygénases/métabolisme , Oxygénases/composition chimique , Ammoniac/composition chimique , Ammoniac/métabolisme , Domaine catalytique , Modèles moléculaires , Spectroscopie de résonance de spin électronique
9.
ACS Sens ; 9(6): 3085-3095, 2024 Jun 28.
Article de Anglais | MEDLINE | ID: mdl-38840550

RÉSUMÉ

Wearable gas sensors have drawn great attention for potential applications in health monitoring, minienvironment detection, and advanced soft electronic noses. However, it still remains a great challenge to simultaneously achieve excellent flexibility, high sensitivity, robustness, and gas permeability, because of the inherent limitation of widely used traditional organic flexible substrates. Herein, an electrospinning polyacrylonitrile (PAN) nanofiber network was designed as a flexible substrate, on which an ultraflexible wearable gas sensor was prepared with in situ assembled polyaniline (PANI) and multiwalled carbon nanotubes (MWCNTs) as a sensitive layer. The unique nanofiber network and strong binding force between substrate and sensing materials endow the wearable gas sensor with excellent robustness, flexibility, and gas permeability. The wearable sensor can maintain stable NH3 sensing performance while sustaining extreme bending and stretching (50% of strain). The Young's modulus of wearable PAN/MWCNTs/PANI sensor is as low as 18.9 MPa, which is several orders of magnitude smaller than those of reported flexible sensors. The water vapor transmission rate of the sensor is 0.38 g/(cm2 24 h), which enables the wearing comfort of the sensor. Most importantly, due to the effective exposure of sensing sites as well as the heterostructure effect between MWCNTs and PANI, the sensor shows high sensitivity to NH3 at room temperature, and the theoretical limit of detection is as low as 300 ppb. This work provides a new avenue for the realization of reliable and high-performance wearable gas sensors.


Sujet(s)
Résines acryliques , Ammoniac , Dérivés de l'aniline , Nanofibres , Nanotubes de carbone , Dispositifs électroniques portables , Nanofibres/composition chimique , Nanotubes de carbone/composition chimique , Dérivés de l'aniline/composition chimique , Résines acryliques/composition chimique , Ammoniac/analyse , Humains , Gaz/analyse , Gaz/composition chimique
10.
ACS Sens ; 9(6): 3282-3289, 2024 Jun 28.
Article de Anglais | MEDLINE | ID: mdl-38864828

RÉSUMÉ

A new type of carbonized polymer dot was prepared by the one-step hydrothermal method of triethoxylsilane (TEOS) and citric acid (CA). The sensor made from carbonized polymer dots (CPDs) showed superior gas sensing performance toward ammonia at room temperature. The Si, O-codoped CPDs exhibited superior ammonia sensing performance at room temperature, including a low practical limit of detection (pLOD) of 1 ppm (Ra/Rg: 1.10, 1 ppm), short response/recovery time (30/36 s, 1 ppm), high humidity resistance (less than 5% undulation when changing relative humidity to 80 from 30%), high stability (less than 5% initial response undulation after 120 days), reliable repeatability, and high selectivity against other interferential gases. The gas sensing mechanism was investigated through control experiments and in situ FTIR, indicating that Si, O-codoping essentially improves the electron transfer capability of CPDs and synergistically dominates the superior ammonia sensing properties of the CPDs. This work presents a facile strategy for constructing novel high-performance, single-component carbonized polymer dots for gas sensing.


Sujet(s)
Ammoniac , Polymères , Température , Ammoniac/analyse , Polymères/composition chimique , Carbone/composition chimique , Gaz/analyse , Gaz/composition chimique , Silicium/composition chimique , Limite de détection , Boîtes quantiques/composition chimique , Oxygène/composition chimique
11.
Microbiol Spectr ; 12(7): e0390223, 2024 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-38842310

RÉSUMÉ

Cryptococcus neoformans and Cryptococcus gattii are both known urease producers and have the potential to cause hyperammonemia. We hypothesized that the risk of hyperammonemia is increased by renal failure, burden of cryptococcal infection, and fungal strain characteristics. We performed a retrospective review of plasma ammonia levels in patients with cryptococcal infections. Risk factors for hyperammonemia were statistically compared between patients with and without hyperammonemia (>53 µmol/L). Cryptococcal cells from three patients included in the study were recovered from our biorepository. Strain characteristics including urease activity, ammonia production, growth curves, microscopy, melanin production, and M13 molecular typing were analyzed and compared with a wild-type (WT) C. neoformans strain. We included 29 patients, of whom 37.9% had hyperammonemia, 59% had disseminated cryptococcal infection (DCI), and 41% had isolated central nervous system infection. Thirty-eight percent of patients had renal failure and 28% had liver disease. Renal failure was associated with 4.4 times (95% confidence interval [CI] 1.5, 13.0) higher risk of hyperammonemia. This risk was higher in DCIs (RR 6.2, 95% CI 1.0, 40.2) versus isolated cryptococcal meningitis (RR 2.5, 95% CI, 0.40, 16.0). Liver disease and cryptococcal titers were not associated with hyperammonemia. C. neoformans from one patient with extreme hyperammonemia demonstrated a 4- to 5-fold increase in extracellular urease activity, slow growth, enlarged cell size phenotypes, and diminished virulence factors. Hyperammonemia was strongly associated with renal failure in individuals with DCI, surpassing associations with liver failure or cryptococcal titers. However, profound hyperammonemia in one patient was attributable to high levels of urease secretion unique to that cryptococcal strain. Prospective studies are crucial to exploring the significance of this association.IMPORTANCECryptococcus produces and secretes the urease enzyme to facilitate its colonization of the host. Urease breaks down urea into ammonia, overwhelming the liver's detoxification process and leading to hyperammonemia in some hosts. This underrecognized complication exacerbates organ dysfunction alongside the infection. Our study investigated this intricate relationship, uncovering a strong association between the development of hyperammonemia and renal failure in patients with cryptococcal infections, particularly those with disseminated infections. We also explore mechanisms underlying increased urease activity, specifically in strains associated with extreme hyperammonemia. Our discoveries provide a foundation for advancing research into cryptococcal metabolism and identifying therapeutic targets to enhance patient outcomes.


Sujet(s)
Cryptococcose , Cryptococcus gattii , Cryptococcus neoformans , Hyperammoniémie , Urease , Humains , Cryptococcose/microbiologie , Hyperammoniémie/microbiologie , Hyperammoniémie/étiologie , Femelle , Études rétrospectives , Mâle , Adulte d'âge moyen , Urease/métabolisme , Adulte , Sujet âgé , Ammoniac/métabolisme , Facteurs de risque , Insuffisance rénale/complications , Insuffisance rénale/microbiologie , Sujet âgé de 80 ans ou plus
12.
Environ Sci Pollut Res Int ; 31(29): 41824-41843, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38862798

RÉSUMÉ

Ammonia nitrogen (NH3-N/NH4+-N) serves as a crucial chemical in biochemistry and fertilizer synthesis. However, it is also a toxic compound, posing risks from eutrophication to direct threats to human health. Ammonia nitrogen pollution pervades water sources, presenting a significant challenge. While several water treatment technologies exist, biological treatment, though widely used, has its limitations. Hence, green and efficient photocatalytic technology emerges as a promising solution. However, current monolithic semiconductor photocatalysts prove inadequate in controlling ammonia nitrogen pollution. Therefore, this review focuses on enhancing semiconductor photocatalysts' efficiency through modification, discussing four mechanisms: (1) mono-ionic modification; (2) metallic and non-metallic modification; (3) construct heterojunctions; and (4) enhancement of synergistic effects of multiple technologies. The influencing factors of photocatalytic ammonia nitrogen removal efficiency are also explored. Moreover, the review outlines the limitations of current photocatalytic pollution treatment and discusses future development trends and research challenges. Currently, the main products of ammonia nitrogen removal include NO3-, NO2-, and N2. To mitigate secondary pollution, the green process of converting ammonia nitrogen to N2 using photocatalysis emerges as a fundamental approach for future treatment. Overall, this review aims to deepen understanding of photocatalysis in ammonia nitrogen treatment and guide researchers toward widespread implementation of this endeavor.


Sujet(s)
Ammoniac , Azote , Purification de l'eau , Ammoniac/composition chimique , Catalyse , Purification de l'eau/méthodes , Azote/composition chimique , Polluants chimiques de l'eau/composition chimique
13.
Environ Sci Pollut Res Int ; 31(29): 42342-42356, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38872036

RÉSUMÉ

The Electrolytic Manganese Residue (EMR) is a by-product of the electrolytic manganese metal (EMM) industry, containing high concentrations of potential pollutants such as NH4+-N and soluble Mn2+. These components pose a serious threat to the ecological environment. To explore accurate, efficient, and harmless treatment methods for EMR, this study proposes a low-temperature thermochemical approach. The orthogonal experiment design investigates the effects of reaction temperature, reaction time, quicklime (CaO), sodium carbonate (Na2CO3), sodium phosphate (Na3PO4) (Reviewer #3), and water consumption on manganese solidified and ammonia removal from EMR. The results indicate that optimal conditions are a reaction temperature of 60 ℃ (Reviewer #3) and a reaction time of 10 min. CaO precipitates Mn2+ as manganese hydroxide (Mn(OH)2) (Reviewer #3), achieving effective manganese solidified and ammonia removal. The addition of Na2CO3 causes Mn2+ to form manganesecarbonate (MnCO3) (Reviewer #3)precipitate, while Na3PO4 makes Mn2+ form Manganese phosphate trihydrate (Mn3(PO4)2·3H2O) (Reviewer #3). Increased water consumption enhances the interaction adequacy between ions. Under optimal conditions (CaO 10%, Na2CO3 1%, Na3PO4 0.5%, and 80% water consumption), the removal rate of ammonium ions reaches 98.5%, and the solidification rate of soluble Mn2+ is 99.9%. The order of influence on ammonium ion removal is CaO > water consumption > Na3PO4 > Na2CO3. Therefore, this study provides a new method for low-cost process disposal and efficient harmless treatment of EMR (Reviewer #3).


Sujet(s)
Manganèse , Manganèse/composition chimique , Température , Ammoniac/composition chimique , Électrolyse
14.
Environ Geochem Health ; 46(7): 218, 2024 Jun 07.
Article de Anglais | MEDLINE | ID: mdl-38849659

RÉSUMÉ

Human activity factors have a significant impact on changes in ammonia nitrogen (NH3-N) content in rivers. Existing research mainly focuses on human activity factors as type factors, and lacks research on the key factors affecting river NH3-N among human activity factors. Therefore, this paper aims to study the key factors affecting human activities on NH3-N in the Huaihe River through various statistical analysis methods. The study found that changes in NH3-N content in the Huaihe River are mainly affected by land use patterns in the basin. There are two different ways in which land use affects NH3-N in rivers: direct effects and indirect effects. We also studied the main pathways through which changes in key factors in human activities affect NH3-N in the Huaihe River by constructing a structural equation model. The results showed that crop sowing area and afforestation area have a significant direct effect on NH3-N in the Huaihe River. In addition, crop sowing area and afforestation area can also affect river NH3-N by regulating the amount of nitrogen fertilizer and human excrement. This study is of great significance for understanding how human activities regulate NH3-N content in rivers.


Sujet(s)
Ammoniac , Rivières , Rivières/composition chimique , Chine , Humains , Ammoniac/analyse , Activités humaines , Surveillance de l'environnement , Agriculture , Polluants chimiques de l'eau/analyse , Azote/analyse , Engrais
15.
Sci Rep ; 14(1): 13886, 2024 06 16.
Article de Anglais | MEDLINE | ID: mdl-38880817

RÉSUMÉ

This study aimed to perform the first external validation of the modified Child-Turcotte-Pugh score based on plasma ammonia (aCTP) and compare it with other risk scoring systems to predict survival in patients with cirrhosis after transjugular intrahepatic portosystemic shunt (TIPS) placement. We retrospectively reviewed 473 patients from three cohorts between January 2016 and June 2022 and compared the aCTP score with the Child-Turcotte-Pugh (CTP) score, albumin-bilirubin (ALBI), model for end-stage liver disease (MELD) and sodium MELD (MELD-Na) in predicting transplant-free survival by the concordance index (C-index), area under the receiver operating characteristic curve, calibration plot, and decision curve analysis (DCA) curve. The median follow-up time was 29 months, during which a total of 62 (20.74%) patients died or underwent liver transplantation. The survival curves for the three aCTP grades differed significantly. Patients with aCTP grade C had a shorter expected lifespan than patients with aCTP grades A and B (P < 0.0001). The aCTP score showed the best discriminative performance using the C-index compared with other scores at each time point during follow-up, it also showed better calibration in the calibration plot and the lowest Brier scores, and it also showed a higher net benefit than the other scores in the DCA curve. The aCTP score outperformed the other risk scores in predicting survival after TIPS placement in patients with cirrhosis and may be useful for risk stratification and survival prediction.


Sujet(s)
Ammoniac , Cirrhose du foie , Anastomose portosystémique intrahépatique par voie transjugulaire , Humains , Femelle , Mâle , Cirrhose du foie/mortalité , Cirrhose du foie/chirurgie , Cirrhose du foie/sang , Ammoniac/sang , Adulte d'âge moyen , Études rétrospectives , Sujet âgé , Pronostic , Courbe ROC , Indice de gravité de la maladie , Adulte
16.
Ying Yong Sheng Tai Xue Bao ; 35(5): 1242-1250, 2024 May.
Article de Chinois | MEDLINE | ID: mdl-38886422

RÉSUMÉ

In this study, we used a high-throughput sequencing technology to survey the dry-wet seasonal change characteristics of soil ammonia-oxidizing bacteria (AOB) communities in the three restoration stages [i.e., Mallotus paniculatus community (early stage), Millettia leptobotrya community (middle stage), and Syzygium oblatum community (later stage)] of Xishuangbanna tropical forest ecosystems. We analyzed the effects of soil physicochemical characteristics on AOB community composition and diversity during tropical forest restoration. The results showed that tropical forest restoration significantly affected the relative abundance of dominant AOB phyla and their dry-wet seasonal variation. The maximum relative abundance of Proteobacteria (71.3%) was found in the early recovery stage, while that of Actinobacteria was found in the late recovery stage (1.0%). The abundances of Proteobacteria and Actinobacteria had the maximum ranges of dry-wet seasonal variation in the early and late stages, respectively. The abundance of dominant AOB genera and its dry-wet seasonal variation varied across tropical forest restoration stages. The maximum average relative abundance of Nitrosospira and Nitrosomonas in the late recovery stage was 66.2% and 1.5%, respectively. In contrast, the abundance of Nitrosovibrio reached its maximum (25.6%) in the early recovery stage. The maximum dry-wet seasonal variation in relative abundance of Nitrosospira and Nitrosomonas occurred in the early recovery stage, while that of Nitrosovibrio occurred in the middle recovery stage. The Chao1, Shannon, and Simpson diversity indices of AOB communities increased along the restoration stages, which were significantly higher in the wet season than in the dry season. The results of canonical correspondence analysis showed that soil easily oxidized carbon was the main factor controlling AOB community diversity and Actinobacteria abundance. Soil bulk density and temperature were the main factors affecting Proteobacteria abundance. Soil pH, microbial biomass carbon, water content, ammonium nitrogen, bulk density, and temperature were the main factors controlling the abundances of Nitrosospira, Nitrosomonas, and Nitrosovibrio. Therefore, tropical forest restoration can regulate the change of relative abundance of dominant AOB taxa via mediating the changes of soil temperature, bulk density, and readily oxidized carbon, leading to an increase in soil AOB community diversity.


Sujet(s)
Ammoniac , Bactéries , Forêts , Oxydoréduction , Saisons , Microbiologie du sol , Climat tropical , Ammoniac/métabolisme , Bactéries/classification , Bactéries/métabolisme , Bactéries/isolement et purification , Bactéries/génétique , Bactéries/croissance et développement , Proteobacteria/isolement et purification , Proteobacteria/classification , Proteobacteria/métabolisme , Proteobacteria/génétique , Chine , Conservation des ressources naturelles , Assainissement et restauration de l'environnement/méthodes , Nitrosomonas/métabolisme , Nitrosomonas/classification , Nitrosomonas/croissance et développement , Forêt pluviale
17.
Ying Yong Sheng Tai Xue Bao ; 35(5): 1283-1292, 2024 May.
Article de Chinois | MEDLINE | ID: mdl-38886427

RÉSUMÉ

To investigate the effects of different irrigation and nitrogen application modes on nitrogen gaseous loss in winter wheat farmland, we conducted a field experiment at Changqing Irrigation Experiment Station in Shandong Province, with two irrigation levels (80%-90% θf(I1) and 70%-80% θf(I2)) and three nitrogen application levels (conventional nitrogen application of 240 kg·hm-2(N1), nitrogen reduction of 12.5% (N2), and nitrogen reduction of 25% (N3)). The results showed that ammonia volatilization and nitrous oxide emission rate peak appeared within 2-4 days after fertilization or irrigation. The ammonia volatilization rate during the chasing fertilizer period was significantly higher than that during the basal fertilizer period. Compared with other treatments, the ave-rage ammonia volatilization rate of I2N2 treatment during the chasing fertilizer period was reduced by 10.1%-51.6%, and the average nitrous oxide emission rate over the whole growth period was reduced by 15.4%-52.2%. The ammonia volatilization rate was significantly positively associated with surface soil pH value and ammonium nitrogen content, while the nitrous oxide emission rate was significantly positively associated with nitrate content in topsoil. The accumulation amount of soil ammonia volatilization and nitrous oxide emission ranged from 0.83-1.42 and 0.11-0.33 kg·hm-2, respectively. Moderate reduction of irrigation water and nitrogen input could effectively reduce cumulative amounts of ammonia volatilization and nitrous oxide emission from winter wheat farmland. The cumulative amounts of ammonia volatilization and nitrous oxide emission under I1N3 and I2N2 treatments were signi-ficantly lower than those under other treatments. The highest winter wheat yield (5615.6 kg·hm-2) appeared in I2N2 treatment. The irrigation water utilization efficiency of I2 was significantly higher than that of I1, with the maximum increase rate of 45.2%. Compared with N1 and N3 treatments, the maximum increase rate of nitrogen fertilizer productivity and agricultural utilization efficiency in N2 reached 15.2% and 31.8%, respectively. In conclusion, the treatment with 70%-80% θf irrigation level and 210 kg·hm-2 nitrogen input could effectively improve the utilization efficiency of irrigation water and nitrogen fertilization and reduce gaseous loss from winter wheat farmland.


Sujet(s)
Ammoniac , Engrais , Azote , Protoxyde d'azote , Triticum , Eau , Triticum/croissance et développement , Triticum/métabolisme , Protoxyde d'azote/analyse , Protoxyde d'azote/métabolisme , Azote/analyse , Azote/métabolisme , Ammoniac/analyse , Ammoniac/métabolisme , Chine , Eau/analyse , Eau/métabolisme , Irrigation agricole/méthodes , Saisons , Biomasse , Sol/composition chimique
18.
Sci Rep ; 14(1): 13868, 2024 06 15.
Article de Anglais | MEDLINE | ID: mdl-38879696

RÉSUMÉ

The purpose of this research was to examine the potential effects of bentonite (BN) supplemented diets on growth, feed utilization, blood biochemistry, and histomorphology of Dicentrarchus labrax. Six treatments in triplicate were tested: B0, B0.5, B1.0, B1.5, B3.0, and B4.5, which represented fish groups fed diets supplemented with 0, 0.5, 1, 1.5, 3, and 4.5% BN, respectively. For 84 days, juveniles' seabass (initial weight = 32.73 g) were fed diets containing 46% protein, three times daily at 3% of body weight. With a 5% daily water exchange, underground seawater (32 ppt) was used. Findings revealed significant improvements in water quality (TAN and NH3), growth (FW, WG and SGR) and feed utilization (FCR, PER and PPV) in fish fed BN-supplemented diets, with the best values in favor of the B1.5 group. Additional enhancements in kidney function indicators (urea and uric acid) and liver enzymes were observed in fish of the BN-treated groups along with a decrease in cholesterol level in the B1.5 group. Further improvements in fish innate immunity (hemoglobin, red blood cells, glucose, total protein, globulin, and immunoglobulin IgM), antioxidant activity (total antioxidative capacity and catalase), and decreased cortisol levels in fish of the BN-treated groups. Histological examinations of the anterior and posterior intestines and liver in groups B1.5 and B3 revealed the healthiest organs. This study recommends BN at a concentration of 1.5% as a feed additive in the Dicentrarchus labrax diet.


Sujet(s)
Ammoniac , Aliment pour animaux , Antioxydants , Serran , Bentonite , Compléments alimentaires , Animaux , Serran/immunologie , Serran/croissance et développement , Serran/métabolisme , Antioxydants/métabolisme , Bentonite/pharmacologie , Bentonite/administration et posologie , Ammoniac/métabolisme , Aliment pour animaux/analyse , Régime alimentaire/médecine vétérinaire
19.
Molecules ; 29(11)2024 May 30.
Article de Anglais | MEDLINE | ID: mdl-38893444

RÉSUMÉ

Leach bed reactors (LBRs) are dry anaerobic systems that can handle feedstocks with high solid content, like chicken manure, with minimal water addition. In this study, the chicken manure was mixed with zeolite, a novel addition, and packed in the LBR to improve biogas production. The resulting leachate was then processed in a continuous stirred tank reactor (CSTR), where most of the methane was produced. The supernatant of the CSTR was returned to the LBR. The batch mode operation of the LBR led to a varying methane production rate (MPR) with a peak in the beginning of each batch cycle when the leachate was rich in organic matter. Comparing the MPR in both systems, the peaks in the zeolite system were higher and more acute than in the control system, which was under stress, as indicated by the acetate accumulation at 2328 mg L-1. Moreover, the presence of zeolite in the LBR played a crucial role, increasing the overall methane yield from 0.142 (control experiment) to 0.171 NL CH4 per g of volatile solids of chicken manure entering the system at a solid retention time of 14 d. Zeolite also improved the stability of the system. The ammonia concentration increased gradually due to the little water entering the system and reached 3220 mg L-1 (control system) and 2730 mg L-1 (zeolite system) at the end of the experiment. It seems that zeolite favored the accumulation of the ammonia at a lower rate (14.0 mg L-1 d-1) compared to the control experiment (17.3 mg L-1 d-1). The microbial analysis of the CSTR fed on the leachate from the LBR amended with zeolite showed a higher relative abundance of Methanosaeta (83.6%) compared to the control experiment (69.1%). Both CSTRs established significantly different bacterial profiles from the inoculum after 120 days of operation (p < 0.05). Regarding the archaeal communities, there were no significant statistical differences between the CSTRs and the inoculum (p > 0.05).


Sujet(s)
Dépollution biologique de l'environnement , Poulets , Fumier , Méthane , Zéolites , Zéolites/composition chimique , Animaux , Anaérobiose , Méthane/métabolisme , Méthane/composition chimique , Bioréacteurs , Biocarburants , Ammoniac/composition chimique , Ammoniac/métabolisme
20.
ACS Appl Mater Interfaces ; 16(24): 30648-30657, 2024 Jun 19.
Article de Anglais | MEDLINE | ID: mdl-38843092

RÉSUMÉ

Organic and inorganic hybrid field-effect transistors (FETs), utilizing layered molybdenum diselenide (MoSe2) and an organic semiconductor poly(3-hexylthiophene) (P3HT), are presented for biosensing applications. A new hybrid device structure that combines organic (P3HT) and inorganic (MoSe2) components is showcased for accurate and selective bioanalyte detection in human bodily fluids to overcome 2D-transition metal dichalcogenides (TMDs) nonspecific interactions. This hybrid structure utilizes organic and inorganic semiconductors' high surface-to-volume ratio, carrier transport, and conductivity for biosensing. Ammonia concentrations in saliva and plasma are closely linked to physiological and pathological conditions of the human body. A highly sensitive hybrid FET biosensor detects total ammonia (NH4+ and NH3) from 0.5 µM to 1 mM concentrations, with a detection limit of 0.65 µM in human bodily fluids. The sensor's ammonia specificity in artificial saliva against interfering species is showcased. Furthermore, the fabricated hybrid FET device exhibits a stable and repeatable response to ammonia in both saliva and plasma, achieving a remarkable response level of 2300 at a 1 mM concentration of ammonia, surpassing existing literature by 10-fold. This hybrid FET biosensing platform holds significant promise for developing a precise tool for the real-time monitoring of ammonia concentrations in human biological fluids, offering potential applications in point-of-care diagnostics.


Sujet(s)
Ammoniac , Techniques de biocapteur , Salive , Transistors électroniques , Ammoniac/analyse , Humains , Techniques de biocapteur/instrumentation , Techniques de biocapteur/méthodes , Salive/composition chimique , Salive/métabolisme , Thiophènes/composition chimique , Molybdène/composition chimique , Limite de détection , Semiconducteurs
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