Hybrid bioreactor built-in with fixed bio-carriers for denitrification with low C/N ratio: Hydrodynamic optimization and microbial divergence.

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.

Bioactive compounds, health benefits and functional food products of sea buckthorn: a review.

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.

Overexpression of phzM contributes to much more production of pyocyanin converted from phenazine-1-carboxylic acid in the absence of RpoS in Pseudomonas aeruginosa.

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.

phz1 contributes much more to phenazine-1-carboxylic acid biosynthesis than phz2 in Pseudomonas aeruginosa rpoS mutant.

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.

Association of specific gut microbiota with polyethylene microplastics caused gut dysbiosis and increased susceptibility to opportunistic pathogens in honeybees.

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.

A study on the influence of perceived distance on China's inbound Tourism and the interaction of non-economic distance: An analysis of dynamic extended gravity model based on 61 countries' entry data (2004-2018).

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.

Discovery of novel 4-(2-fluorophenoxy)quinoline derivatives bearing 4-oxo-1,4-dihydrocinnoline-3-carboxamide moiety as c-Met kinase inhibitors.

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.

Integration of Untargeted Metabolomics and Object-Oriented Data-Processing Protocols to Characterize Acerola Powder Composition as Functional Food Ingredient.

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.

Non-weight-bearing exercise attenuates papain-induced knee osteoarthritis in rats via the TLR4/MyD88/NF-κB signaling pathway.

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.

Health outcomes of 100% orange juice and orange flavored beverage: A comparative analysis of gut microbiota and metabolomics in rats.

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.

2023 International African Swine Fever Workshop: Critical Issues That Need to Be Addressed for ASF Control.

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.

Comparison of freshly squeezed, Non-thermally and thermally processed orange juice based on traditional quality characters, untargeted metabolomics, and volatile overview.

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.

Nano- and micro-polystyrene plastics disturb gut microbiota and intestinal immune system in honeybee.

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.

Identification of novel biomarkers in chilled and frozen chicken using metabolomics profiling and its application.

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.

Impact of Clarified Apple Juices with Different Processing Methods on Gut Microbiota and Metabolomics of Rats.

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.

Development and validation of a multi-residue analytical method for veterinarian and human pharmaceuticals in livestock urine and blood using UHPLC-QTOF.

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.

Simultaneous determination of multi-class antibiotics and steroid hormones drugs in livestock and poultry faeces using liquid chromatography-quadrupole time-of-flight mass spectrometry.

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.

LasR Might Act as an Intermediate in Overproduction of Phenazines in the Absence of RpoS in Pseudomonas aeruginosa.

As an opportunistic bacterial pathogen, Pseudomonas aeruginosa PAO1 contains two phenazineproducing gene operons, phzA1B1C1D1E1F1G1 (phz1) and phzA2B2C2D2E2F2G2 (phz2), each of which is independently capable of encoding all enzymes for biosynthesizing phenazines, including phenazine-1-carboxylic acid and its derivatives. Other previous study reported that the RpoS-deficient mutant SS24 overproduced pyocyanin, a derivative of phenazine-1- carboxylic acid. However, it is not known how RpoS mediates the expression of two phz operons and regulates pyocyanin biosynthesis in detail. In this study, with deletion of the rpoS gene in the PAΔphz1 mutant and the PAΔphz2 mutant respectively, we demonstrated that RpoS exerted opposite regulatory roles on the expression of the phz1and phz2 operons. We also confirmed that the phz1 operon played a critical role and especially biosynthesized much more phenazines than the phz2 operon when the rpoS gene was knocked out in P. aeruginosa. By constructing the translational reporter fusion vector lasR'-'lacZ and the chromosomal fusion mutant PAΔlasR::lacZ, we verified that RpoS deficiency caused increased expression of lasR, a transcription regulator gene in a first quorum sensing system (las) that activates overexpression of the phz1 operon, suggesting that in the absence of RpoS, LasR might act as an intermediate in overproduction of phenazine biosynthesis mediated by the phz1 operon in P. aeruginosa.

Fast learning of fiber orientation distribution function for MR tractography using convolutional neural network.

PURPOSE: In diffusion-weighted magnetic resonance imaging (DW-MRI), the fiber orientation distribution function (fODF) is of great importance for solving complex fiber configurations to achieve reliable tractography throughout the brain, which ultimately facilitates the understanding of brain connectivity and exploration of neurological dysfunction. Recently, multi-shell multi-tissue constrained spherical deconvolution (MSMT-CSD) method has been explored for reconstructing full fODFs. To achieve a reliable fitting, similar to other model-based approaches, a large number of diffusion measurements is typically required for MSMT-CSD method. The prolonged acquisition is, however, not feasible in practical clinical routine and is prone to motion artifacts. To accelerate the acquisition, we proposed a method to reconstruct the fODF from downsampled diffusion-weighted images (DWIs) by leveraging the strong inference ability of the deep convolutional neural network (CNN). METHODS: The method treats spherical harmonics (SH)-represented DWI signals and fODF coefficients as inputs and outputs, respectively. To compensate for the reduced gradient directions with reduced number of DWIs in acquisition in each voxel, its surrounding voxels are incorporated by the network for exploiting their spatial continuity. The resulting fODF coefficients are fitted with applying the CNN in a multi-target regression model. The network is composed of two convolutional layers and three fully connected layers. To obtain an initial evaluation of the method, we quantitatively measured its performance on a simulated dataset. Then, for in vivo tests, we employed data from 24 subjects from the Human Connectome Project (HCP) as training set and six subjects as test set. The performance of the proposed method was primarily compared to the super-resolved MSMT-CSD with the decreasing number of DWIs. The fODFs reconstructed by MSMT-CSD from all available 288 DWIs were used as training labels and the reference standard. The performance was quantitatively measured by the angular correlation coefficient (ACC) and the mean angular error (MAE). RESULTS: For the simulated dataset, the proposed method exhibited the potential advantage over the model reconstruction. For the in vivo dataset, it achieved superior results over the MSMT-CSD in all the investigated cases, with its advantage more obvious when a limited number of DWIs were used. As the number of DWIs was reduced from 95 to 25, the median ACC ranged from 0.96 to 0.91 for the CNN, but 0.93 to 0.77 for the MSMT-CSD (with perfect score of 1). The angular error in the typical regions of interest (ROIs) was also much lower, especially in multi-fiber regions. The average MAE for the CNN method in regions containing one, two, three fibers was, respectively, 1.09°, 2.75°, and 8.35° smaller than the MSMT-CSD method. The visual inception of the fODF further confirmed this superiority. Moreover, the tractography results validated the effectiveness of the learned fODF, in preserving known major branching fibers with only 25 DWIs. CONCLUSION: Experiments on HCP datasets demonstrated the feasibility of the proposed method in recovering fODFs from up to 11-fold reduced number of DWIs. The proposed method offers a new streamlined reconstruction procedure and exhibits promising potential in acquisition acceleration for the reconstruction of fODFs with good accuracy.

Efficacy evaluation of three modified-live PRRS vaccines against a local strain of highly pathogenic porcine reproductive and respiratory syndrome virus.

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.