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Hydrodynamics played an important role in the design and operation of bioreactors for wastewater treatment. In this work, an up-flow anaerobic hybrid bioreactor built-in with fixed bio-carriers was designed and optimized using computational fluid dynamics (CFD) simulation. The results indicated that the flow regime involving with vortex and dead zone was greatly affected by the positions of water inlet and bio-carrier modules. The ideal hydraulic features were obtained when the water inlet and bio-carrier modules located 9 cm and 60 cm above the bottom of reactor. Using the optimum hybrid system for nitrogen removal from wastewater with low carbon-to-nitrogen ratio (C/N = 3), the denitrification efficiency could reach 80.9 ± 0.4%. Illumina sequencing of 16S rRNA gene amplicons revealed that the microbial community divergence occurred among the biofilm on bio-carrier, the suspended sludge phase and the inoculum. Especially, the relative abundance of denitrifying genera Denitratisoma in the biofilm of bio-carrier reaches 5.73%, 6.2 times higher than that in the suspended sludge, implying the imbedded bio-carrier was conductive to enrich the specific denitrifiers to polish the denitrification performance with low carbon source. This work provided an effective method for the design optimization of bioreactor based on CFD simulation, and developed a hybrid reactor with fixed bio-carrier for nitrogen removal from wastewater with low C/N ratio.
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Esgotos , Águas Residuárias , Desnitrificação , Hidrodinâmica , RNA Ribossômico 16S , Reatores Biológicos , Nitrogênio/análise , Biofilmes , Carbono , Eliminação de Resíduos LíquidosRESUMO
Sea buckthorn (Hippophae rhamnoides L.), which has been categorized as a "medicine food homology" fruit by China's National Health Commission for both nutritional and medicinal purposes, has nearly 200 kinds of nutritive and bioactive compounds such as polyunsaturated fatty acids, carotenoids, sugar alcohols, superoxide dismutase and phytosterols. Significant bioactivity, including cardiovascular improvement, antidiabetic and anti-obesity activity, have highlighted the application of sea buckthorn. This review compiled a database of the phytochemical compounds in sea buckthorn, which contains the contents of 106 nutrients and 74 bioactive compounds. The health benefits of sea buckthorn and its extracts were summarized and the mechanism of anti-oxidation and anti-inflammation were introduced in detail. Seventeen common marketed products of sea buckthorn from 8 countries were collected. A future scope is really needed to explore the mechanism of sea buckthorn bioactive compounds along with the incorporation cost-effective functional food products.
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Hippophae , Fitosteróis , Carotenoides/análise , Frutas/química , Alimento Funcional , Hippophae/química , Fitosteróis/análiseRESUMO
Pyocyanin produced by Pseudomonas aeruginosa is a key virulence factor that often causes heavy damages to airway and lung in patients. Conversion of phenazine-1-carboxylic acid to pyocyanin involves an extrametabolic pathway that contains two enzymes encoded, respectively, by phzM and phzS. In this study, with construction of the rpoS-deficient mutant, we first found that although phenazine production increased, pyocyanin produced in the mutant YTΔrpoS was fourfold much higher than that in the wild-type strain YT. To investigate this issue, we constructed phzM-lacZ fusion on a vector and on the chromosome. By quantifying ß-galactosidase activities, we confirmed that expression of the phzM was up-regulated when the rpoS gene was inactivated. However, no changes occurred in the expression of phzS and phzH when the rpoS was knocked out. Taken together, overproduction of the SAM-dependent methyltransferase (PhzM) might contribute to the increased pyocyanin in the absence of RpoS in P. aeruginosa.
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Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Metiltransferases/biossíntese , Oxigenases de Função Mista/biossíntese , Pseudomonas aeruginosa/metabolismo , Piocianina/biossíntese , Fator sigma/genética , Humanos , Metiltransferases/genética , Oxigenases de Função Mista/genética , Fenazinas/metabolismo , Pseudomonas aeruginosa/genética , Fatores de Virulência/metabolismoRESUMO
Pseudomonas aeruginosa PAO1, a common opportunistic bacterial pathogen, contains two phenazine-biosynthetic operons, phz1 (phzA1 B1 C1 D1 E1 F1 G1 ) and phz2 (phzA2 B2 C2 D2 E2 F2 G2 ). Each of two operons can independently encode a set of enzymes involving in the biosynthesis of phenazine-1-carboxylic acid. As a global transcriptional regulator, RpoS mediates a lot of genes involving secondary metabolites biosynthesis in many bacteria. In an other previous study, it was reported that RpoS deficiency caused overproduction of pyocyanin, a derivative of phenazine-1-carboxylic acid in P. aeruginosa PAO1. But it is not known how RpoS mediates the expression of each of two phz operons and modulates phenazine-1-carboxylic acid biosynthesis in detail. In this study, by deleting the rpoS gene in the mutant PNΔphz1 and the mutant PNΔphz2, we found that the phz1 operon contributes much more to phenazine-1-carboxylic acid biosynthesis than the phz2 operon in the absence of RpoS. With the construction of the translational and transcriptional fusion vectors with the truncated lacZ reporter gene, we demonstrated that RpoS negatively regulates the expression of phz1 and positively controls the expression of phz2, and the regulation of phenazine-1-carboxylic acid biosynthesis mediated by RopS occurs at the posttranscriptional level, not at the transcriptional level. Obviously, two copies of phz operons and their differential expression mediated by RpoS might help P. aeruginosa adapt to its diverse environments and establish infection in its hosts.
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Proteínas de Bactérias/genética , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Fator sigma/genética , Regulação Bacteriana da Expressão Gênica , Óperon/genética , Fenazinas/metabolismo , Deleção de SequênciaRESUMO
Individuals with autistic traits (AT) are widely distributed in the general population. Strengthening understanding of AT can provide a broader perspective for autism research as well as more accurate diagnosis and personalized treatment plans for clinical practice. Previous studies on attention bias among high-AT individuals have yielded inconsistent results, which may relate to different stages of attention. In this study, we selected two groups with high and low level AT from the general population, and then adopted the odd-one-out search task, combined with Event-related potential (ERP) technique, conducted both attention orientation and attention dissociation tasks, to explore attention bias and electroencephalogram (EEG) characteristics towards threatening emotional faces in these groups. The behavioral data showed no accelerated attention orientation to angry faces and neutral faces; however, there was attention dissociation difficulty for angry faces. Compared with low-AT individuals, the EEG results showed that high-AT individuals have acceleration of attention orientation and attention dissociation difficulty for threatening emotional faces. From the perspective of top-down concept-driven processing, these findings suggest that high-AT individuals have attention bias for cognitive processing of threatening stimuli, which is mainly due to acceleration of attention orientation and attention dissociation difficulties for threatening information.
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In the post-epidemic era, the restart of China's inbound tourism is imminent. However, there are gaps in our current understanding of how distance perception dynamically affects inbound tourism in China. In order to understand the past patterns of inbound tourism in China, we mapped the data of 61 countries of origin from 2004 to 2018 into a dynamic expanding gravity model to understand the effects of cultural distance, institutional distance, geographical distance, and economic distance on inbound tourism in China and revealed the dynamic interaction mechanism of non-economic distance perception on inbound tourism in China. Our research results show that cultural distance has a positive impact on China's inbound tourism, while institutional distance has a negative impact. The significant finding is that the dynamic interaction of the above two kinds of perceived distance can still have a positive impact on China's inbound tourism. Its practical significance is that it can counteract the influence of institutional distance by strengthening the cultural distance. Generally speaking, geographical distance and institutional distance restrict China's inbound tourism flow, while cultural distance, economic distance, and interactive perceptual distance promote China's inbound tourism flow.
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Turismo , China , Humanos , Modelos Teóricos , Percepção de Distância , Viagem/economia , GravitaçãoRESUMO
In recent years, the role of naval ship power has become increasingly prominent in regional conflicts and military operations worldwide, and the powerful capabilities demonstrated by naval forces have also been valued by countries around the world. While naval forces are frequently deployed to carry out various tasks, the intensity of equipment wear and tear on ships is also significantly increasing, posing a huge challenge to the maintenance and support capabilities of ship equipment. In the actual process of ship equipment maintenance, a series of risk factors such as cost, schedule, and quality will have a significant impact on the entire ship maintenance project, and even affect the success or failure of the entire project. This article first decomposes the project process of ship maintenance projects, further analyzes the various risk factors of ship maintenance projects based on the project decomposition situation, and then distinguishes the overall project, project process, and project risk factors to establish an intelligent agent group model for simulation analysis. Through the above simulation analysis, we will conduct in-depth research on the specific impact of project risks on ship maintenance projects, and analyze and verify the positive role and practical significance of project risk management in project risk control and project efficiency improvement. In the process of the above research content, methods and measures for risk management of ship maintenance projects are proposed, providing scientific and efficient risk management suggestions for such projects, improving the scientific management efficiency of ship maintenance projects, and contributing to the improvement of the quality and efficiency of project management.
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The emergence of microplastics as contaminants has raised concerns regarding their potential toxicity. Recent studies on microplastic pollution caused by food packaging have drawn attention to its impact on health. However, despite being used extensively in food packaging, there is little knowledge about the toxicity of polyethylene microplastics (PE-MPs). Here, we studied the toxicity of PE-MPs on the model animal honeybees using different particle sizes (1 µm, 10 µm, 100 µm in diameter). Oral exposure to 100-µm PE-MPs resulted in elevated honeybee mortality and increased their susceptibility to pathogens. This is likely due to the mechanical disruption and gut microbial dysbiosis by PE-MPs. Snodgrassella, a core functional gut bacteria, was specifically enriched on the surface of PE-MPs, which perturbs the gut microbial communities in honeybees. Furthermore, the increased mortality in challenge trials with the opportunistic pathogen Hafnia alvei for PE-MPs pre-exposed honeybees revealed a potential health risk. These findings provide fresh insights into evaluating the potential hazards associated with PE-MPs.
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Microbioma Gastrointestinal , Polietileno , Abelhas , Animais , Polietileno/toxicidade , Microplásticos , Plásticos , DisbioseRESUMO
A series of novel 4-(2-fluorophenoxy)quinoline derivatives containing 4-oxo-1,4-dihydrocinnoline-3-carboxamide moiety were designed, synthesized and evaluated for their in vitro biological activities against c-Met kinase and six typical cancer cell lines (A549, H460, HT-29, MKN-45, U87MG and SMMC-7721). All the prepared compounds showed moderate to excellent antiproliferative activity, and the analysis of their structure-activity relationships indicated that 2-chloro or 2-trifluoromethyl substituted phenyl group on the 1-position of cinnoline ring was more favorable for antitumor activity. In this study, a promising compound 33, with a c-Met IC50 value of 0.59 nM, was identified as a multitargeted receptor tyrosine kinase inhibitor.
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Anilidas/síntese química , Antineoplásicos/síntese química , Inibidores de Proteínas Quinases/síntese química , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Quinolinas/síntese química , Anilidas/química , Anilidas/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/química , Quinolinas/química , Quinolinas/farmacologia , Espectrometria de Fluorescência , Relação Estrutura-AtividadeRESUMO
A high intake of sugar-sweetened fruity beverage (FB) is associated with a higher risk of metabolic syndromes, but the health outcome of 100% fruit juice (FJ) intake remains unclear. We aim to reveal health outcomes of diet intervention (FJ or FB) with system profiling via interaction of gut microbiota and metabolomics in a rat (Rattus norvegicus) model. Firstly, the glucose, sucrose, fructose, and bioactive metabolites of FJ and FB were analyzed, and FJ possessed higher sucrose and flavonoids, while FB showed higher glucose and fructose. Secondly, C0 was set as the control group on Day 0, and a 4-week diet invention was performed to control, FJ-intake, and FB-intake groups with normal saline, FJ, and FB, respectively. The results showed that FJ improved alpha diversity and decreased the Firmicutes/Bacteroidota ratio (F/B ratio) of gut microbiota and prevented insulin resistance. However, FB possessed unchanged microbial diversity and enhanced F/B ratio, causing insulin resistance with renal triglyceride accumulation. In summary, FJ, although naturally containing similar amounts of total free sugars as FB, could be a healthier drink choice.
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Acerola powder has been experiencing a surge in demand as a functional food ingredient, particularly due to its usage in vitamin C supplements. However, limited research has been conducted on its other bioactive compounds. In this study, we employed metabolomics and object-oriented data-processing protocols to comprehensively characterize acerola powder. To ensure maximum coverage of metabolomics, we selected a 50% methanol aqueous solution as the extraction solvent and utilized the HSS T3 column for chromatography analysis. Through this approach, we successfully identified a total of 175 compounds in acerola powder, encompassing amino acids and peptides, polyphenols, organic acids, and various other compounds. Additionally, we measured the total phenolic content (TPC) and assessed the antioxidant activity of acerola powder. Furthermore, we analyzed the differential composition of acerola fruit and juice powder, identifying polyphenols and lipids as primary markers in fruit powder, while peptides emerged as key markers in juice powder. Notably, two specific peptides, Thr-Trp and Val-Tyr, were identified as antioxidant peptides. Overall, our study provides novel composition data for acerola powder, shedding light on its potential as a functional food ingredient. These findings contribute to the development and utilization of acerola powder in the formulation of functional food products.
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BACKGROUND AND AIM: Knee osteoarthritis (KOA) is characterized by joint wear and degeneration. Unfortunately, the medical community currently lacks effective treatment options for this disease. Suspension exercise therapy is considered an effective form of non-weight-bearing exercise for treating KOA. However, its mechanism of intervention in KOA is unclear. Therefore, this study aimed to evaluate the protective effects of non-weight-bearing exercise on rats with KOA and attempted to explore the underlying mechanisms. METHODS: In this study, a papain-induced KOA model was constructed, and the pathological changes in cartilage tissue were observed by hematoxylin and eosin (H&E) staining and scored according to the Mankin scoring principle. The serum levels of interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay. Reverse transcription-quantitative polymerase chain reaction and Western blotting were used to detect the expression of mRNA and proteins in the TLR4/MyD88/NF-κB signaling pathway. RESULTS: H&E staining and Mankin score data confirmed that non-weight-bearing exercise significantly improved articular cartilage degradation compared with that in the model group. Further, we observed that non-weight-bearing exercise differentially reduced serum levels of IL-1ß, IL-6, and TNF-α. Mechanistically, non-weight-bearing exercise downregulated gene and protein expression of TLR4, MyD88, and NF-κB in cartilage tissue. CONCLUSION: Non-weight-bearing exercise resulted in the progression of KOA by modulating the TLR4/MyD88/NF-κB signaling pathway and decreasing the levels of the inflammatory cytokines IL-1ß, IL-6, and TNF-α to slow down the degeneration of articular cartilage.
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NF-kappa B , Osteoartrite do Joelho , Condicionamento Físico Animal , Animais , Ratos , Proteínas Adaptadoras de Transdução de Sinal , Interleucina-6 , Fator 88 de Diferenciação Mieloide , Osteoartrite do Joelho/induzido quimicamente , Osteoartrite do Joelho/terapia , Papaína/efeitos adversos , Transdução de Sinais , Receptor 4 Toll-Like , Fator de Necrose Tumoral alfaRESUMO
The 2023 International African Swine Fever Workshop (IASFW) took place in Beijing, China, on 18-20 September 2023. It was jointly organized by the U.S.-China Center for Animal Health (USCCAH) at Kansas State University (KSU) and the Chinese Veterinary Drug Association (CVDA) and sponsored by the United States Department of Agriculture Foreign Agricultural Service (USDA-FAS), Harbin Veterinary Research Institute, and Zoetis Inc. The objective of this workshop was to provide a platform for ASF researchers around the world to unite and share their knowledge and expertise on ASF control and prevention. A total of 24 outstanding ASF research scientists and experts from 10 countries attended this meeting. The workshop included presentations on current ASF research, opportunities for scientific collaboration, and discussions of lessons and experiences learned from China/Asia, Africa, and Europe. This article summarizes the meeting highlights and presents some critical issues that need to be addressed for ASF control and prevention in the future.
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Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Humanos , Febre Suína Africana/prevenção & controle , Febre Suína Africana/epidemiologia , Ásia , China/epidemiologia , África/epidemiologia , Sus scrofa , Surtos de Doenças/veterináriaRESUMO
The NOVA food classification system, divides foods into four categories, namely unprocessed and minimally processed foods, processed culinary ingredients, processed foods, and ultra-processed foods. With the recently increasing pursuit of healthy diets, special attention to minimally processed foods has become crucial. According to NOVA, freshly squeezed, high pressure processing (HPP) and pasteurized orange juice are minimally processed foods. In this study, the differences in the quality and composition of these minimally processed juice are explored, as it was found that their traditional quality characteristics were too weak to illustrate their difference. However, based on untargeted metabolomics, two differential compounds were identified between freshly squeezed and HPP orange juice, in addition to 15 differential compounds between freshly squeezed and pasteurized orange juice. Moreover, all the pasteurized orange juice in this study was deemed to be out of the acceptance area of freshly squeezed and HPP orange juice in a data-driven soft independent modeling of class analogy (dd-SIMCA) model based on volatile overview. The results of this study provide data for clarifying the compositional differences between minimally processed juice for their further subclassification.
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Citrus sinensis , Fast Foods , Manipulação de Alimentos , Sucos de Frutas e Vegetais , MetabolômicaRESUMO
Micro- (MPs) and nano-plastics (NPs) have become emerging pollutants in the environment. Their wide distribution and capacity as a vector of hazardous materials threaten various organisms. Honeybees have been used as bioindicators for pollutants as their gut microbiota offers advantages for addressing how it alters the host health and exploring the processes of environmental pollutants affecting gut community dynamics. In this study, the effects of plastic particles of different sizes on honeybees' health were investigated. Oral exposure to polystyrene (PS) particles with a diameter of 100 nm significantly decreased the whole-body weight and survival rate of honeybees and induced intestinal dysplasia. As the increase of the feeding time from Day 0 to Day 15, the MPs moved to and accumulated in the rectum, where most bee gut symbionts colonized. Scanning electron microscope observation showed that 100-nm PS particles adhered to the germination pore of pollen, while 1- and 10-µm PS particles were attached by gut bacteria. We found that 100-nm PS treatment decreased the relative abundance of Lactobacillus and Bifidobacterium in the guts. Correspondingly, PS treatment stimulated immune inhibitory genes and depressed genes related to detoxification and energy balance. Furthermore, 100-nm PS treated honeybees became more susceptible to the pathogenic Hafnia alvei, leading to a five-times higher mortality rate. These results indicated the adverse impacts of NPs on honeybees, which extends our knowledge regarding the emerging health risks of plastic debris, especially at the nanoscale.
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Poluentes Ambientais , Microbioma Gastrointestinal , Poluentes Químicos da Água , Animais , Abelhas , Sistema Imunitário , PoliestirenosRESUMO
Merchants used frozen chicken to pass it off as chilled chicken, resulting in Economically Motivated Adulteration incidents. Here in this work, firstly, we established OPLS-DA and OPLS-R models based on metabolomics to obtain differential metabolites in chilled and frozen chicken (with different storage times), the PLS-DA model based on above differential compounds could achieve accuracy of 91% (training) and 100% (testing) for the adulteration identification of uncooked chilled and frozen chicken. Secondly, cooking study was carried out to identify the discrepancy of the cooked chilled and frozen chicken. Higher nicotinamide, o-acetyl-l-carnitine, hypoxanthine, and IMP levels indicated better nutrition quality and more desirable flavor in chilled chicken nuggets, while higher bitter and sour peptides in frozen chicken nuggets indicated the loss of freshness.
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Galinhas , Culinária , Animais , Biomarcadores , Culinária/métodos , Congelamento , MetabolômicaRESUMO
The consumption of processed foods has increased compared to that of fresh foods in recent years, especially due to the coronavirus disease 2019 pandemic. Here, we evaluated the health effects of clarified apple juices (CAJs, devoid of pectin and additives) processed to different degrees, including not-from-concentrate (NFC) and from-concentrate (FC) CAJs. A 56-day experiment including a juice-switch after 28 days was designed. An integrated analysis of 16S rRNA sequencing and untargeted metabolomics of cecal content were performed. In addition, differences in the CAJs tested with respect to nutritional indices and composition of small-molecule compounds were analyzed. The NFC CAJ, which showed a higher phenolic content resulting from the lower processing degree, could improve microbiota diversity and influence its structure. It also reduced bile acid and bilirubin contents, as well as inhibited the microbial metabolism of tryptophan in the gut. However, we found that these effects diminished with time by performing experiment extension and undertaking juice-switching. Our study provides evidence regarding the health effects of processed foods that can potentially be applied to public health policy decision making. We believe that NFC juices with a lower processing degree could potentially be healthier than FC juice.
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COVID-19 , Microbioma Gastrointestinal , Malus , Animais , Sucos de Frutas e Vegetais , Malus/química , Metabolômica/métodos , RNA Ribossômico 16S/genética , RatosRESUMO
The aim of this work is to contribute to the assessment of multi-residue analysis of veterinarian and human pharmaceuticals using UHPLC-QTOF in livestock urine and blood (cattle, chicken, sheep and pig). Firstly, an in-house database including compound name, monoisotopic mass, chemical formula, retention time, chemical structure, and three CID MS-MS spectra of the 234 selected drugs were built for qualitative detection. Secondly, the method validation result showed that all the 234 drugs exhibited good linearity with determination coefficients (R2) higher than 0.999. Then, the distribution of the drugs recoveries, intra-day RSD and inter-day RSD results for all seven matrices were tested. Finally, after a carefully cross check, 150 veterinarian and human pharmaceuticals could meet the methodological requirements (recovery, 50-120%; intra-day RSD ≤ 15%, inter-day RSD ≤ 20%) in all seven matrices. Our results suggested that although the main applications of UHPLC-QTOF are directed towards detection and identification of the compounds, this method should be also applied for quantitative purposes.
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Cromatografia Líquida de Alta Pressão/métodos , Drogas Veterinárias , Animais , Bovinos , Galinhas , Modelos Lineares , Gado , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ovinos , Espectrometria de Massas por Ionização por Electrospray , Suínos , Drogas Veterinárias/sangue , Drogas Veterinárias/isolamento & purificação , Drogas Veterinárias/urinaRESUMO
A method for simultaneous determination of multi-class antibiotics and steroid hormone analysis in faeces of livestock and poultry was developed using liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF MS). An in-house database was built for 156 detected drugs using Personal Compound Database Library software (PCDL) including compound name, monoisotopic mass, chemical formula, RT, chemical structure and three CID MS/MS spectra. The linearity result showed that all the drugs exhibited good linearity with determination coefficients (R2) higher than 0.99. The drug recoveries and their RSDs for all three faeces samples (pig, cattle and chicken) were tested and 81, 96 and 92 drugs were chosen for analysis in pig, cattle and chicken faeces, respectively. Further validation showed that 73 veterinary drugs in all three kinds of faeces samples can be quantified in one analytical run. This work shows that qualitative and quantitative analysis using LC-QTOF MS represents a simple, sensitive, low-cost and high-throughput methodology in routine laboratory analyses.
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Antibacterianos/análise , Fezes/química , Hormônios Esteroides Gonadais/análise , Animais , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Aves DomésticasRESUMO
Highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) is characterized by high fever and high mortality in pigs of all ages and has severely affected the pork industry of China in the last decades. This study evaluated the differences in protection conferred by of three MLV PRRS vaccines derived from classical PRRSV (C-PRRSV, VR2332) and HP-PRRSV (TJM-F92 and JXA1-R) against the field challenge of HP-PRRSV TP strain (JXA1-R like). Compared to the experiment pigs in control group which were vaccinated with normal saline, the MLV PRRS vaccinated pigs had milder clinical symptoms, fewer pathological changes in the lung, and higher body weight gain at the end of the study. However, piglets vaccinated with VR2332 had higher body temperature, higher viral loads and lower body weight gain when compared with piglets vaccinated with TJM-F92 or JXA1-R vaccines at the end of the study. The results demonstrated that VR2332 vaccine provided a limited cross-protection against the HP-PRRSV TP strain infection, while in contrast the TJM-F92 and JXA1-R vaccines provided more efficacious protection. The findings of this study could serve as a valuable reference guide for the pig producers and veterinarians when considering the choice of which type of MLV PRRS vaccines to protect their pig herds against field challenge by HP-PRRSV TP strain.