Development and Application of a Micro-device for Rapid Detection of Ammonia Nitrogen in Environmental Water / 分析化学

The analysis of ammonia nitrogen in real water samples is challenging due to matrix interferences and difficulties for rapid on-site analysis.On the basis of the standard method,i.e.water quality-determination of ammonia nitrogen-salicylic acid spectrophotometry(HJ 536-2009),a simple device for online detecting ammonia nitrogen was developed using a sequential injection analysis(SIA)system in this work.The ammonia nitrogen transformation system,color reaction system,and detection system were built in compatible with the SIA system,respectively.In particular,the detection system was assembled by employing light-emitting diode as the light source,photodiode as the detector,and polyvinylchloride tube as the cuvette,thus significantly reducing the volume,energy consumption and fabricating cost of the detection system.As a result,the accurate analysis of ammonia nitrogen in complex water samples was achieved.A quantitative detection of ammonia nitrogen in water sample was obtained in 12 min,along with linear range extending to 1000 μmol/L,precisions(Relative standard deviation,RSD)of 4.3%(C=10 μmol/L,n=7)and 4.2%(C=500 μmol/L,n=7),and limit of detection(LOD)of 0.65 μmol/L(S/N=3,n=7).The results of interfering experiments showed that the detection of ammonia nitrogen by the developed device was not interfered by the common coexisting ions and components,therefore the environmental water could be directly analyzed,such as reservoir water,domestic sewage,sea water and leachate of waste landfill.The analytical results were consistent with those obtained by the environmental protection standard method(Water quality determination of ammonia nitrogen-salicylic acid spectrophotometry,HJ 536-2009).In addition,the spiking recoveries were in the range of 92.3%-98.1%,further confirming the accuracy and practicality of the developed device.

Relationship between the initial serum ammonia level and prognosis in critically ill patients with non-hepatic disease: a retrospective cohort study based on eICU Collaborative Research Database / 西安交通大学学报(医学版)

【Objective】 To investigate the relationship between the initial serum ammonia level and the risk of ICU and hospital mortalities in critically ill patients without hepatic disease. 【Methods】 A retrospective cohort study was conducted among patients admitted to the eICU Collaborative Research Database (eICU-CRD) for a single admission who had serum ammonia test records within 48 hours of the first ICU admission and had no hepatic disease. The age, sex, ethnicity, Acute Physiologic and Chronic Health Evaluation Ⅳ score (APACHE Ⅳ score), treatment methods, complications, and outcomes were extracted. Univariable and multivariable Logistic regression were used to analyze the relationship between serum ammonia level and the risk of mortality. Interactions were used to analyze whether the relationship between serum ammonia level and the risk of mortality differed in subgroups of APACHE Ⅳ scores, age, sex, and ethnicity; subgroup analyses were made. 【Results】 A total of 1 674 patients were included. The multivariable Logistic regression showed that for every 10 μg/dL increase in ammonia, the risk of ICU death increased by 6.9% (OR=1.069, 95% CI: 1.036-1.104), and the risk of hospital death increased by 4.6% (OR=1.046, 95% CI: 1.017-1.076). The risk of ICU death was 1.7 times greater in patients with initial ammonia level of 49-82 μg/dL than in those with <49 μg/dL (OR=1.700, 95% CI: 1.165-2.482), the risk of ICU death was 2.862 times greater in patients with a level of ≥82 μg/dL compared to those with <49 μg/dL (OR=2.862, 95% CI: 1.792-4.570), and the risk of hospital death was 1.844 times higher in the ≥82 μg/dL group than in the <49 μg/dL group (OR=1.844, 95% CI: 1.213-2.804). There were no significant differences between initial ammonia level and the risk of mortalities in different subgroups of APACHEⅣ scores, age, sex, or ethnicity. 【Conclusion】 In critically ill patients without hepatic disease, elevated initial serum ammonia level after ICU admission is associated with a high risk of ICU and hospital mortality.

Manejo inicial de la hiperamonemia aguda en pediatría / Initial management of acute hyperammonemia in pediatrics

La hiperamonemia constituye una emergencia médica. No existen publicaciones que hagan referencia a la disponibilidad de recursos, insumos y conocimientos necesarios para el manejo inicial de esta por parte del pediatra en nuestro país, pero, según la experiencia de los autores, los recursos necesarios no se encuentran disponibles los 365 días del año en una gran porción de nuestro territorio. Sobre la base de este estado de situación, de una revisión bibliográfica internacional sobre el tema y de la experiencia de los autores, se elaboraron una serie de recomendaciones para el manejo pediátrico inicial de esta emergencia, que tienen como objetivo poder reducir las deficiencias, permitir una sospecha clínica adecuada que lleve a un diagnóstico y tratamiento de emergencia oportunos, con utilización racional de recursos farmacológicos (algunos de ellos de alto costo), para reducir la morbimortalidad que asocia la patología.

Hyperammonemia is a medical emergency. There are no publications regarding the availability of resources, supplies, and knowledge necessary for the initial management of hyperammonemia by pediatricians in Argentina; however, according to the authors' experience, the necessary resources are not available all year round in a large portion of our territory. Based on such state of affairs, an international bibliographic review on this topic and the authors' experience, we developed a series of recommendations for the initial pediatric management of this emergency, with the objective of reducing deficiencies, allowing adequate clinical suspicion leading to a timely diagnosis and emergency management and a rational use of pharmacological resources (some of which are costly) to reduce the morbidity and mortality associated with hyperammonemia.

Breath-by-breath measurement of exhaled ammonia by acetone-modifier positive photoionization ion mobility spectrometry via online dilution and purging sampling / 药物分析学报

Exhaled ammonia(NH3)is an essential noninvasive biomarker for disease diagnosis.In this study,an acetone-modifier positive photoionization ion mobility spectrometry(AM-PIMS)method was developed for accurate qualitative and quantitative analysis of exhaled NH3 with high selectivity and sensitivity.Acetone was introduced into the drift tube along with the drift gas as a modifier,and the characteristic NH3 product ion peak of(C3H6O)4NH4+(K0=1.45 cm2/V·s)was obtained through the ion-molecule reaction with acetone reactant ions(C3H6O)2H+(K0=1.87 cm2/V·s),which significantly increased the peak-to-peak resolution and improved the accuracy of exhaled NH3 qualitative identification.Moreover,the interference of high humidity and the memory effect of NH3 molecules were significantly reduced via online dilution and purging sampling,thus realizing breath-by-breath measurement.As a result,a wide quantitative range of 5.87-140.92 μmol/L with a response time of 40 ms was achieved,and the exhaled NH3 profile could be synchronized with the concentration curve of exhaled CO2.Finally,the analytical capacity of AM-PIMS was demonstrated by measuring the exhaled NH3 of healthy subjects,demon-strating its great potential for clinical disease diagnosis.

Assessment of myocardial viability in ischemic heart disease by integrated PET/MR / 中华核医学与分子影像杂志

Objective:To evaluate the value of integrated PET/MR in assessing myocardial viability in ischemic heart disease.Methods:A total of 39 patients (28 males, 11 females; age (60.1±12.0) years) diagnosed with ischemic heart disease in Xuanwu Hospital, Capital Medical University were retrospectively enrolled from September 2020 to December 2021. All patients underwent cardiac 13N-NH 3·H 2O and 18F-FDG PET/MR examinations. Late gadolinium enhancement (LGE) sequence was included in MRI scan. PET and MRI images were analyzed and myocardial viability of each myocardial segment was evaluated according to the American Heart Association (AHA) 17 segment method. The extent of left ventricular infarcted myocardium was measured based on PET and MRI images. Weighted Kappa test was used to evaluate the agreement of PET and MRI in assessing myocardial viability. The extent of infarcted myocardium measured by PET and MRI was compared by paired- t test, and Pearson correlation analysis was used to assess the correlation between them. Results:There was a moderate agreement between PET and MRI in assessing myocardial viability ( Kappa=0.532, P<0.001), with the agreement rate of 69.83%(463/663). There was no significant difference but strong correlation between the extents of infarcted myocardium measured by PET and MRI ((23.89±14.23)% vs (23.55±11.90)%; t=-0.24, P=0.809; r=0.79, P<0.001). In segments with normal perfusion and metabolism on PET, 22.52% (100/444) showed abnormal enhancement on MRI. On the other hand, 39.89% (73/183) of the segments classified as non-viable on MRI showed normal or viable on PET. Conclusion:Integrated PET/MR is able to take full advantage of the complementary nature of PET and MRI, achieving the comprehensive and accurate evaluation of myocardial viability.

Diagnostic value of a combined serology-based model for minimal hepatic encephalopathy in patients with compensated cirrhosis / 中华检验医学杂志

Objective:To investigate the diagnostic accuracy of serological indicators and evaluate the diagnostic value of a new established combined serological model on identifying the minimal hepatic encephalopathy (MHE) in patients with compensated cirrhosis.Methods:This prospective multicenter study enrolled 263 compensated cirrhotic patients from 23 hospitals in 15 provinces, autonomous regions and municipalities of China between October 2021 and August 2022. Clinical data and laboratory test results were collected, and the model for end-stage liver disease (MELD) score was calculated. Ammonia level was corrected to the upper limit of normal (AMM-ULN) by the baseline blood ammonia measurements/upper limit of the normal reference value. MHE was diagnosed by combined abnormal number connection test-A and abnormal digit symbol test as suggested by Guidelines on the management of hepatic encephalopathy in cirrhosis. The patients were randomly divided (7∶3) into training set ( n=185) and validation set ( n=78) based on caret package of R language. Logistic regression was used to establish a combined model of MHE diagnosis. The diagnostic performance was evaluated by the area under the curve (AUC) of receiver operating characteristic curve, Hosmer-Lemeshow test and calibration curve. The internal verification was carried out by the Bootstrap method ( n=200). AUC comparisons were achieved using the Delong test. Results:In the training set, prevalence of MHE was 37.8% (70/185). There were statistically significant differences in AMM-ULN, albumin, platelet, alkaline phosphatase, international normalized ratio, MELD score and education between non-MHE group and MHE group (all P<0.05). Multivariate Logistic regression analysis showed that AMM-ULN [odds ratio ( OR)=1.78, 95% confidence interval ( CI) 1.05-3.14, P=0.038] and MELD score ( OR=1.11, 95% CI 1.04-1.20, P=0.002) were independent risk factors for MHE, and the AUC for predicting MHE were 0.663, 0.625, respectively. Compared with the use of blood AMM-ULN and MELD score alone, the AUC of the combined model of AMM-ULN, MELD score and education exhibited better predictive performance in determining the presence of MHE was 0.755, the specificity and sensitivity was 85.2% and 55.7%, respectively. Hosmer-Lemeshow test and calibration curve showed that the model had good calibration ( P=0.733). The AUC for internal validation of the combined model for diagnosing MHE was 0.752. In the validation set, the AUC of the combined model for diagnosing MHE was 0.794, and Hosmer-Lemeshow test showed good calibration ( P=0.841). Conclusion:Use of the combined model including AMM-ULN, MELD score and education could improve the predictive efficiency of MHE among patients with compensated cirrhosis.

Gene cloning and enzymatic activity analysis of phenylalanine ammonia-lyase from Sinopodophyllum hexandrum (Royle) Ying / 生物工程学报

Phenylalanine ammonia-lyase (PAL) is the key entry enzyme of plant phenylpropanoid pathway. It plays an important role in the biosynthesis of podophyllotoxin, an anti-tumor lignan that is currently produced from its main natural source Sinopodophyllum hexandrum (Royle) Ying. In this study, we cloned the gene ShPAL encoding phenylalanine ammonia-lyase by RT-PCR from the root of S. hexandrum ecotype inhabited in the Aba' district, Sichuan, based on its public SRA transcriptome data-package. Bioinformatics analyses showed that the ShPAL-encoded protein is composed of 711 amino acids, contains the conserved domains of PAL, and has the signature motif within the active center of aromatic ammonia-lyases. Moreover, ShPAL protein was predicted to have a secondary structure mainly composed of α-helix and random coil, a typical 'seahorse' shape monomer tertiary structure, and a homologous tetramer three-dimensional structure by Swiss-Modelling. The phylogenetic lineage analysis indicated ShPAL was of the highest sequence identity and the shortest evolutionary distance with the PAL of Epimedium sagittatum from the same Berberidaceae family. Subcellular localization experiments showed that ShPAL protein was mainly distributed in the cytoplasm, despite of a minority on the endoplasmic reticulum membrane. Furthermore, ShPAL protein was recombinantly expressed in Escherichia coli and purified by histidine-tag affinity chromatography. Its enzymatic activity was determined up to 20.91 U/mg, with the optimum temperature of 41 ℃ and pH of 9.0. In contrast, the enzyme activity of its F130H mutant decreased by about 23.6%, yet with the same trends of change with temperature and pH, confirming that phenylalanine at this position does affect the substrate specificity of PAL. Both the wild type and the mutant have relatively poor thermostability, but good pH-stability. These results may help to further investigate the regulatory role of PAL in the process of podophyllotoxin biosynthesis and advance the heterologous synthesis of podophyllotoxin to protect the germplasm resource of S. hexandrum. They also demonstrate that ShPAL has a potential application in biochemical industry and biomedicine.

Effect of plasma ammonia on β-amyloid of CSF and cognitive function in mild Alzheimer's disease / 临床神经病学杂志

Objective To investigate effect of plasma ammonia on β-amyloid(Aβ)of CSF and cognitive function in mild Alzheimer's disease(AD).Methods A total of 108 mild AD patients admitted to our hospital and 47 volunteers(HC group)were studied,the cognitive function were measured and plasma ammonia were detected.The mild AD patients were divided into normal ammonia group(ADA-group)and hyperammonemia group(ADA + group)by the plasma ammonia level.The level of Aβ42,Aβ40,total tau and phosphorylated tau protein in CSF of AD patients were detected,and the results were compared.Results Compared with HC group,the MMSE and Montreal Cognitive Assessment(MoCA)in the ADA-group and ADA + group were significantly lower(all P＜0.001).The MoCA of ADA + group was significantly lower than that of ADA-group(P＜0.001).The plasma ammonia of ADA + group were significantly higher than those of ADA-group and HC group(all P＜0.001).The levels of Aβ42 and Aβ40 in ADA + group were significantly lower than those of ADA-group(t =2.29,P =0.024;t =2.72,P =0.008).In ADA + group,the plasma ammonia level was negatively correlated with the MoCA score(r =-0.47,P＜0.001)and level of Aβ42 in CSF(r =-0.63,P＜0.001).The level of Aβ42 played a partial mediating role between the plasma ammonia level and cognitive function,and mediating effect accounted for 45.94%of the total effect.Conclusion The plasma ammonia level is elevated in some AD patients,high plasma ammonia level may reduce the Aβ42 level in CSF,contributes to Aβ42 deposition which forms the amyloid plaques,ultimately aggravates cognitive impairment.

Protective Effect of Xiaochaihutang on Ammonia-Induced Astrocyte Edema in Rats by Inhibition of NF-κB Signaling Pathway / 世界科学技术-中医药现代化

Objective To observe the effect of Xiaochaihutang on ammonia-induced edema of astrocytes in rats and explore the mechanism of Xiaochaihutang in the treatment of cerebral edema based on NF-κB signaling pathway.Methods Astrocytes were isolated from the cerebral cortex of SD rats 1-2 days old.When the cell content was more than 95%,the cells could be subcultured and divided into three groups:Vehicle group(10%blank control group serum,Vehicle),Model group(10%blank control group serum+5 mmol·L-1 ammonium chloride,Model),and Xiaochaihutang group(10%serum+5 mmol·L-1 ammonium chloride,XCHT).The expression of AQP4 was detected by immunofluorescence.The levels of AQP4,GFAP,and TNF-α were detected by RT-PCR and Western blot.NF-κB P65 was measured by Western blot.Results ① Ammonium chloride increased the expression of AQP4 in astrocytes(P<0.01)and decreased the expression of GFAP(P<0.05,P<0.01),however,the expression of AQP4 in astrocytes decreased(P<0.01)while GFAP increased(P<0.05)after the intervention of serum containing Xiaochaihutang.② Compared with the Vehicle group,the expression level of TNF-α and phosphorylation of NF-κB P65 in the Model group was significantly increased(P<0.05),while after Xiaochaihutang serum medicated treatment,TNF-α and phosphorylation of NF-κB P65 content lower(P<0.05).Conclusion Xiaochaihutang can improve the edema of astrocytes induced by ammonia and enhance the activity of astrocytes.Its mechanism may be related to inhibition of NF-κB signaling pathways,and reduce inflammation medium(especially TNF-α)produced and released.

Bladder microenvironment actuated proteomotors with ammonia amplification for enhanced cancer treatment

Enzyme-driven micro/nanomotors consuming in situ chemical fuels have attracted lots of attention for biomedical applications. However, motor systems composed by organism-derived organics that maximize the therapeutic efficacy of enzymatic products remain challenging. Herein, swimming proteomotors based on biocompatible urease and human serum albumin are constructed for enhanced antitumor therapy via active motion and ammonia amplification. By decomposing urea into carbon dioxide and ammonia, the designed proteomotors are endowed with self-propulsive capability, which leads to improved internalization and enhanced penetration in vitro. As a glutamine synthetase inhibitor, the loaded l-methionine sulfoximine further prevents the conversion of toxic ammonia into non-toxic glutamine in both tumor and stromal cells, resulting in local ammonia amplification. After intravesical instillation, the proteomotors achieve longer bladder retention and thus significantly inhibit the growth of orthotopic bladder tumor in vivo without adverse effects. We envision that the as-developed swimming proteomotors with amplification of the product toxicity may be a potential platform for active cancer treatment.

Study on the relationship between local muscle fatigue and related metabolic biomarkers in simulated manual lifting / 中国职业医学

{L-End}Objective To analyze the local muscle response under continuous ergonomic workload by simulating manual lifting, and to screen the sensitive metabolic biomarkers during fatigue process. {L-End}Methods A total of 13 healthy male volunteers were selected as the study subjects using simple random sampling method. Study subjects underwent repetitive simulated manual lifting for four periods (T1 to T4), each lasting 12 minutes. The degree of work-related fatigue in the forearm, upper arm, shoulder, back, and leg muscles, and the whole body was accessed using Borg 6-20 Rating of Perceived Exertion (RPE) Scale. The venous blood samples were collected from elbow between each two periods to detect the levels of eight metabolic biomarkers: ammonia, lactate, creatine kinase, lactate dehydrogenase (LDH), C-terminal telopeptide of type Ⅰ collagen (CTX-Ⅰ), C-terminal telopeptide of type Ⅱ collagen (CTX-Ⅱ), cartilage oligomeric matrix protein (COMP), and calcium ions. {L-End}Results The RPE scores of the study subjects for the muscles of five body parts and the whole body increased with the increasing lifting periods (all P<0.01). Fatigue was observed in all target muscles, with overall body fatigue occurring in the T2 period. The levels of ammonia, lactate, creatine kinase, LDH, COMP, and calcium ions in the serum of study subjects were higher in the T1 to T4 periods than in the T0 period (all P<0.05). The serum CTX-Ⅰ level was higher in the T1 and T3 periods than that in the T0 period (all P<0.05) , and the serum CTX-Ⅱ level was higher in the T1, T2 and T4 periods than that in the T0 period (all P<0.05). The level of these eight serum metabolic biomarkers fluctuated during the T1 to T4 periods. The serum creatine kinase level increased with the period of lifting (all P<0.05). The serum lactate level was higher in the T3 period than those in the T1 and T2 periods (all P<0.05). The serum LDH and calcium ion levels were higher in the T2 to T4 periods than that in the T1 period (all P<0.05). The serum COMP level was higher in the T2 and T3 periods than that in the T1 period (all P<0.05). Except for CTX-Ⅰ, the levels of other seven metabolic markers in serum were higher in individuals after fatigue than before fatigue (all P<0.05). {L-End}Conclusion Serum metabolic biomarkers such as ammonia, lactate, creatine kinase, calcium ions, LDH, CTX-Ⅱ, and COMP exhibit significant changes before and after fatigue. These metabolic biomarkers could be used as sensitive biomarkers for evaluating muscle fatigue during repetitive works.

Characterization of highly active tyrosine ammonia lyase and its application in biosynthesis of p-coumaric acid / 生物工程学报

p-coumaric acid is one of the aromatic compounds that are widely used in food, cosmetics and medicine due to its properties of antibacterium, antioxidation and cardiovascular disease prevention. Tyrosine ammonia-lyase (TAL) catalyzes the deamination of tyrosine to p-coumaric acid. However, the lack of highly active and specific tyrosine ammonia lyase limits cost-effective microbial production of p-coumaric acid. In order to improve biosynthesis efficiency of p-coumaric acid, two tyrosine ammonia-lyases, namely Fc-TAL2 derived from Flavobacterium columnare and Fs-TAL derived from Flavobacterium suncheonense, were selected and characterized. The optimum temperature (55 ℃) and pH (9.5) for Fs-TAL and Fc-TAL2 are the same. Under optimal conditions, the specific enzyme activity of Fs-TAL and Fc-TAL2 were 82.47 U/mg and 13.27 U/mg, respectively. Structural simulation and alignment analysis showed that the orientation of the phenolic hydroxyl group of the conserved Y50 residue on the inner lid loop and its distance to the substrate were the main reasons accounting for the higher activity of Fs-TAL than that of Fc-TAL2. The higher activity and specificity of Fs-TAL were further confirmed via whole-cell catalysis using recombinant Escherichia coli, which could convert 10 g/L tyrosine into 6.2 g/L p-coumaric acid with a yield of 67.9%. This study provides alternative tyrosine ammonia-lyases and may facilitate the microbial production of p-coumaric acid and its derivatives.

Semi-rational design improves the catalytic activity of phenylalanine ammonia lyase from Anabaena variabilis / 药学学报

Phenylalanine ammonia lyase (PAL) can catalyze L-phenylalanine to produce trans-cinnamic acid, which is widely used in the fields of pharmacy, food and agriculture. In particular, phenylalanine ammonia lyase from Anabaena variabilis (AvPAL) is the only protein drug for the treatment of phenylketonuria. However, the poor activity and low stability limit the application in industry of AvPAL. In this study, the key amino acids of substrate-binding cavity in AvPAL were identified by screening the single site saturation mutagenesis library. Subsequently, the impact of replacing M222 with the additional 19 amino acids on activity was also evaluated by site-directed mutagenesis. It was found that the kcat values of mutants M222L and M222V were 90% and 60% higher than that of AvPAL, and the kcat/Km was 1.4 and 1.5 times as that of AvPAL. Molecular docking results revealed that the higher activity of M222L and M222V may be due to the increase of hydrophobicity favorable for the substrate-binding cavity. This study is important for elucidating the structure-function relationship of AvPAL.

Emergency psychological intervention of acute ammonia leakage event / 中华劳动卫生职业病杂志

Objective: To analyze the situation of emergency psychological intervention in an acute ammonia leakage event, and to provide reference for emergency response. Methods: In August 2020, the emergency treatment of 65 patients admitted by Zhangqiu District People's Hospital Affiliated to Jining Medical College of Shandong Province in June 2019 in the ammonia tank car leakage incident was analyzed, the psychological intervention in emergency after the incident was collected, the anxiety and depression were evaluated by symptom checklist 90 (SCL-90) , and targeted psychological intervention was implemented according to the psychological evaluation results, And analyze the intervention efficiency. Results: Among the 65 patients, there were 52 cases of ammonia stimulation reaction, 11 cases of mild poisoning and 2 cases of moderate poisoning. There were 60 cases of chest tightness and dyspnea, 11 cases of bloody sputum, 58 cases of sore throat, 43 cases of hoarseness, 28 cases of photophobia and tears, 13 cases of blurred vision, 18 cases of nausea and vomiting, and 2 cases of dry and wet rales in the lungs. The scores of somatization, depression, anxiety, hostility, phobia, paranoia and negative coping in patients with mild and moderate poisoning were higher than those in patients with stimulus response (P<0.05) . The effective rate of intervention was 98.7%. Conclusion: Emergency psychological evaluation and intervention in mass public health events are helpful to the treatment of patients.

Molecular cloning and characterization of three phenylalanine ammonia-lyase genes from Schisandra chinensis / 中国天然药物

Phenylalanine ammonia-lyase (PAL), which catalyzes the conversion from L-phenylalanine to trans-cinnamic acid, is a well-known key enzyme and a connecting step between primary and secondary metabolisms in the phenylpropanoid biosynthetic pathway of plants and microbes. Schisandra chinensis, a woody vine plant belonging to the family of Magnoliaceae, is a rich source of dibenzocyclooctadiene lignans exhibiting potent activity. However, the functional role of PAL in the biosynthesis of lignan is relatively limited, compared with those in lignin and flavonoids biosynthesis. Therefore, it is essential to clone and characterize the PAL genes from this valuable medicinal plant. In this study, molecular cloning and characterization of three PAL genes (ScPAL1-3) from S. chinensis was carried out. ScPALs were cloned using RACE PCR. The sequence analysis of the three ScPALs was carried out to give basic characteristics followed by docking analysis. In order to determine their catalytic activity, recombinant protein was obtained by heterologous expression in pCold-TF vector in Escherichia coli (BL21-DE3), followed by Ni-affinity purification. The catalytic product of the purified recombinant proteins was verified using RP-HPLC through comparing with standard compounds. The optimal temperature, pH value and effects of different metal ions were determined. Vmax, Kcat and Km values were determined under the optimal conditions. The expression of three ScPALs in different tissues was also determined. Our work provided essential information for the function of ScPALs.

Oral lienal peptides improve ammonia-induced coughing and inflammation in mice / 中国临床药理学与治疗学

To study the effect of oral lienal polypeptide on cough and inflammation in mice, in order to expand the clinical application of immune modulator lienal polypeptide and provide a new strategy for relieving cough and inflammation. METHODS: The cough model of mice was induced by concentrated ammonia. The cough frequency and tolerance latency of mice within 6 minutes were recorded every day. The histopathological changes of spleen and lung were evaluated by HE staining and spleen index. TNF-α, IL-1β and IL-6 levels in spleen and lung of mice was detected by ELISA. RESULTS: Oral administration of spleen polypeptide could prolong the tolerance latency of mice to concentrated ammonia to a certain extent and significantly reduce the cough frequency of mice. HE staining showed that oral spleen polypeptide could significantly reduce the alveolar surface area and improve lung expansion in mice. The results of ELISA showed that oral spleen polypeptide decreased the levels of some proinflammatory factors in spleen and lung. CONCLUSION: Lienal polypeptide can alleviate cough and emphysema like symptoms induced by ammonia, improve immune ability and inflammation in mice.

Ammonia gas for bacterial control in poultry litter

ABSTRACT: The current techniques used in the disinfection of reused poultry litter, such as lime addition, windrowing and plastic cover on the surface, do not guarantee the elimination of pathogenic microorganisms, causing damage to the environment and animal health. Gram negative bacteria, i.e., Salmonella and Escherichia coli, can be transmitted from one batch to another through reused litter, causing health damage to broilers and humans that consume food contaminated by these agents. Our study assessed the effectiveness of the methods plastic cover on the surface (PCS) and plastic cover on the surface with ammonia gas injection (PCSAI) in the control of Gram negative bacteria. The results obtained, both in laboratory conditions (Experiment 1) and in the field (Experiment 2), demonstrate that the method PCSAI with 0.22% ammonia gas had a significant reduction (P 0.05) of Gram negative bacteria in the period of 48 hours This new methodology for disinfecting poultry litter will allow its reuse in a practical and safe way, improving the preservation of the environment, of the health of broilers and consumers of poultry products.

RESUMO: O reaproveitamento de camas aviárias na criação de frangos de corte é uma prática muito utilizada no Brasil. Essa prática reduz custos de produção e contribui na conservação do meio ambiente. As técnicas atuais utilizadas na desinfecção de camas aviárias reaproveitadas, como adição de cal, enleiramento e lona na superfície, não garantem a eliminação de microrganismos patogênicos porque não geram quantidade suficiente de amônia. O gás amônia, em concentrações elevadas, tem efeito biocida. Bactérias Gram negativas, como as Salmonelas e Escherichia coli, podem ser transmitidas de um lote para outro através do reaproveitamento da cama, ocasionando prejuízos para a saúde das aves e dos humanos que consomem alimentos contaminados por estes agentes. Este trabalho avaliou a eficácia do método lona na superfície com injeção de gás amônia no controle de microrganismos Gram negativos. Os resultados obtidos demostraram que esse método controlou os microrganismos Gram negativos num período de 48 horas em camas de frangos de corte reaproveitadas. Assim, essa nova metodologia de desinfecção de camas de aviário permitirá sua reutilização de forma prática e segura, melhorando a saúde das aves e dos consumidores dos produtos avícolas.

Ammonia gas for bacterial control in poultry litter / Gás amônia para controle bacteriano em cama aviária

The current techniques used in the disinfection of reused poultry litter, such as lime addition, windrowing and plastic cover on the surface, do not guarantee the elimination of pathogenic microorganisms, causing damage to the environment and animal health. Gram negative bacteria, i.e., Salmonella and Escherichia coli, can be transmitted from one batch to another through reused litter, causing health damage to broilers and humans that consume food contaminated by these agents. Our study assessed the effectiveness of the methods plastic cover on the surface (PCS) and plastic cover on the surface with ammonia gas injection (PCSAI) in the control of Gram negative bacteria. The results obtained, both in laboratory conditions (Experiment 1) and in the field (Experiment 2), demonstrate that the method PCSAI with 0.22% ammonia gas had a significant reduction (P<0.05) of Gram negative bacteria in the period of 48 hours This new methodology for disinfecting poultry litter will allow its reuse in a practical and safe way, improving the preservation of the environment, of the health of broilers and consumers of poultry products.

O reaproveitamento de camas aviárias na criação de frangos de corte é uma prática muito utilizada no Brasil. Essa prática reduz custos de produção e contribui na conservação do meio ambiente. As técnicas atuais utilizadas na desinfecção de camas aviárias reaproveitadas, como adição de cal, enleiramento e lona na superfície, não garantem a eliminação de microrganismos patogênicos porque não geram quantidade suficiente de amônia. O gás amônia, em concentrações elevadas, tem efeito biocida. Bactérias Gram negativas, como as Salmonelas e Escherichia coli, podem ser transmitidas de um lote para outro através do reaproveitamento da cama, ocasionando prejuízos para a saúde das aves e dos humanos que consomem alimentos contaminados por estes agentes. Este trabalho avaliou a eficácia do método lona na superfície com injeção de gás amônia no controle de microrganismos Gram negativos. Os resultados obtidos demostraram que esse método controlou os microrganismos Gram negativos num período de 48 horas em camas de frangos de corte reaproveitadas. Assim, essa nova metodologia de desinfecção de camas de aviário permitirá sua reutilização de forma prática e segura, melhorando a saúde das aves e dos consumidores dos produtos avícolas.

Hiperamonemia como causa de diálisis no renal / Hyperammonemia as a cause of non-renal dialysis

Resumen La hiperamonemia es una condición frecuente en pacientes cirróticos y en el contexto de una causa no cirrótica se relaciona con aumento en la producción de amonio o alteración en su eliminación. La presentación clínica de esta condición es inespecífica: va desde alteración del comportamiento hasta estado de coma, siendo una de las causas de diálisis no renal por determinados valores o refractariedad a manejo médico. Se presenta el caso de una mujer de 35 años, quien ingresó al servicio de urgencias con alteración del estado de conciencia, niveles de amonio elevados y masa hipervascular en hígado. Los estudios de aminoácidos limitantes del ciclo de la urea y ácido orótico urinario fueron normales y la biopsia de la lesión hepática reportó carcinoma hepático fibrolamelar, al cual se atribuyó la presencia de shunt portosistémico que causaba la hiperamonemia. Se indicó diálisis por persistencia de elevaciones de amonio y poca respuesta al tratamiento médico. Dada la evolución de la paciente, fue necesario reiniciar la terapia reemplazo renal por reaparición de estado encefalopático al suspender la misma. Esta terapia se mantuvo hasta el trasplante hepático que se realizó como tratamiento del carcinoma, con posterior estabilización de niveles de amonio y suspensión de la diálisis.

Abstract Hyperammonemia is a common condition in cirrhotic patients. In the context of a non-cirrhotic cause, this is related to the increase in its production of ammonium or alteration in its elimination. The clinical presentation is nonspecific, from the alteration of the behavior to the coma, being one of the causes of non-renal dialysis due to certain values or refractoriness to medical management. The case of a 35-year-old woman is presented, who is admitted to the emergency department with altered state of consciousness, elevated ammonium levels and hypervascular mass in the liver. Biopsy of the liver lesion reports fibrolamellar liver carcinoma. The presence of a portosystemic shunt that causes hyperammonemia is attributed to this pathology. Dialysis is indicated by persistence of ammonium elevations with little response to medical treatment. In its evolution, it required a restart of renal replacement due to a reappearance of the encephalopathic state when it was suspended. This therapy is maintained until liver transplantation performed as a carcinoma treatment, with subsequent stabilization of ammonium levels and dialysis suspension.

Aerobic stability of tifton 85 silage with and without pre-drying in the sun

The objective of this study was to evaluate pH, ammoniacal nitrogen, and aerobic stability of silage of Tifton 85 grass silage with two dry matter contents at different silos opening times. The experimental design was completely randomized, in a subdivided plots scheme, in which the silages constituted the plots and aerobic exposure times the subplots, with four replications. To verify the aerobic stability of the silages, the temperature and pH were analyzed at seven hours after the silos were opened (1, 24, 48, 72, 96, 120, and 144 hours). The pH reached adequate levels for conservation only after 90 days of fermentation for the silages with and without pre-drying in the sun. Ammoniacal nitrogen remained below the recommended limits in both silages. As for the silage temperature, no loss of aerobic stability was observed. However, the observed pH revealed a break instability after 72 hours when the silos were opened at 28 days, with no changes for the remaining silage periods. It is possible to obtain suitable silages from Tifton 85 with or without pre-warming in the sun, however, a minimum fermentation period of 90 days should be adopted. The studied silages presented high aerobic stability, but when kept silage for only 28 days, they should be consumed by the animals within 48 hours after the supply.