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The Porcine reproductive and respiratory syndrome (PRRS) causes severe financial losses to the global swine industry. Due to continuous virus evolution, the protection against the PRRS provided by current vaccines is limited. In order to find new antiviral strategies, this study investigated the antiviral potential of antimicrobial peptides (AMPs) against PRRSV. Given the diversity of PRRSV strains and the limited effectiveness of existing vaccines in controlling PRRSV, this study evaluated the inhibitory effects of KLAK, Cecropin B, Piscidin1, and Caerin1.1 on 3 strains of PRRSV (lineage 5 classical strain, lineage 8 highly pathogenic strain, and lineage 1 NADC30-like strain). Caerin1.1 exhibited significant dose-dependent antiviral activity, with an effective concentration (EC50) of 7.5⯵M. Caerin1.1 effectively inhibited PRRSV replication when added before or in early infection but showed reduced effectiveness when added in late infection, indicating its potential involvement in targeting early transcription mechanisms of viral RNA polymerase and significantly upregulating cytokine gene expression. In the NADC30 strain-based animal infection model, Caerin1.1 treatment significantly reduced lung viral loads and inflammation in the lungs of PRRSV-infected pigs, with a mortality rate of 0â¯% (0/5) in the treated group compared to 66.67â¯% (4/6) in the untreated group, indicating a reduction in the mortality rate. Additionally, compared with the untreated group, the Caerin1.1-treated group showed significant improvements, such as lighter fever, more daily weight gain, less clinical symptoms, less viral load in blood, and less virus oral shedding (P < 0.05). These findings reveal the potential of antimicrobial peptides as PRRSV therapeutic agents and suggest that Caerin1.1 is a promising candidate for a novel anti-PRRSV drug.
Assuntos
Peptídeos Antimicrobianos , Antivirais , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Carga Viral , Replicação Viral , Animais , Vírus da Síndrome Respiratória e Reprodutiva Suína/efeitos dos fármacos , Suínos , Síndrome Respiratória e Reprodutiva Suína/tratamento farmacológico , Síndrome Respiratória e Reprodutiva Suína/virologia , Antivirais/farmacologia , Replicação Viral/efeitos dos fármacos , Peptídeos Antimicrobianos/farmacologia , Carga Viral/efeitos dos fármacos , Pulmão/virologia , Pulmão/efeitos dos fármacos , Peptídeos Catiônicos Antimicrobianos/farmacologia , Linhagem CelularRESUMO
Group A rotaviruses (RVAs) are major causes of severe gastroenteritis in infants and young animals. To enhance our understanding of the relationship between human and animals RVAs, complete genome data are necessary. We screened 92 intestinal and stool samples from diarrheic piglets by RTâPCR targeting the VP6 gene, revealing a prevalence of 10.9%. RVA was confirmed in two out of 5 calf samples. We successfully isolated two porcine samples using MA104 cell line. The full-length genetic constellation of the two isolates were determined to be G9-P[23]-I5-R1-C1-M1-A8-N1-T7-E1-H1, with close similarity to human Wa-like and porcine strains. Sequence analysis revealed the majority of genes were closely related to porcine and human RVAs. Phylogenetic analysis revealed that these isolates might have their ancestral origin from pigs, although some of their gene segments were related to human strains. This study reveals evidence of reassortment and possible interspecies transmission between pigs and humans in China.
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Genoma Viral , Filogenia , Infecções por Rotavirus , Rotavirus , Doenças dos Suínos , Animais , Rotavirus/genética , Rotavirus/isolamento & purificação , Rotavirus/classificação , Suínos , Infecções por Rotavirus/virologia , Infecções por Rotavirus/veterinária , Infecções por Rotavirus/transmissão , Infecções por Rotavirus/epidemiologia , Humanos , China/epidemiologia , Doenças dos Suínos/virologia , Doenças dos Suínos/transmissão , Doenças dos Suínos/epidemiologia , Bovinos , Fezes/virologia , Sequenciamento Completo do Genoma , Genótipo , Diarreia/virologia , Diarreia/veterinária , Diarreia/epidemiologia , Linhagem Celular , Vírus Reordenados/genética , Vírus Reordenados/isolamento & purificação , Vírus Reordenados/classificaçãoRESUMO
The aim of this study was to investigate if the supplementation of folic acid and taurine can relieve the adverse effects of different levels of heat stress (HS) on growth performance, physiological indices, antioxidative capacity, immunity, rumen fermentation and microbiota. A total of 24 Dorper × Hu crossbred lambs (27.51 ± 0.96 kg) were divided into four groups: control group (C, 25 °C), moderate HS group (MHS, 35 °C), severe HS group (SHS, 40 °C), and the treatment group, under severe HS (RHS, 40 °C, 4 and 40 mg/kg BW/d coated folic acid and taurine, respectively). Results showed that, compared with Group C, HS significantly decreased the ADG of lambs (p < 0.05), and the ADG in the RHS group was markedly higher than in the MHS and SHS group (p < 0.05). HS had significant detrimental effects on physiological indices, antioxidative indices and immune status on the 4th day (p < 0.05). The physiological indices, such as RR and ST, increased significantly (p < 0.05) with the HS level and were significantly decreased in the RHS group, compared to the SHS group (p < 0.05). HS induced the significant increase of MDA, TNF-α, and IL-ß, and the decrease of T-AOC, SOD, GPx, IL-10, IL-13, IgA, IgG, and IgM (p < 0.05). However, there was a significant improvement in these indices after the supplementation of folic acid and taurine under HS. Moreover, there were a significant increase in Quinella and Succinivibrio, and an evident decrease of the genera Rikenellaceae_RC9_gut_group and Asteroleplasma under HS (p < 0.05). The LEfSe analysis showed that the genera Butyrivibrio, Eubacterium_ventriosum_group, and f_Bifidobacteriaceae were enriched in the MHS, SHS and RHS groups, respectively. Correlated analysis indicated that the genus Rikenellaceae_RC9_gut_group was positively associated with MDA, while it was negatively involved in IL-10, IgA, IgM, and SOD (p < 0.05); The genus Anaeroplasma was positively associated with the propionate and valerate, while the genus Succinivibrio was negatively involved in TNF-α (p < 0.05). In conclusion, folic acid and taurine may alleviate the adverse effects of HS on antioxidant capacity, immunomodulation, and rumen fermentation of lambs by inducing changes in the microbiome that improve animal growth performance.
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Recently, the relationship between the goat host and its gastrointestinal microbiome has emerged as a hallmark of host-microbiota symbiosis, which was indispensable for the proper physiological function that convert the plant biomass to livestock products. However, little integrative information about the establishment of gastrointestinal microflora in goats exists. Herein, we characterized the colonizing process of the bacterial community in the digesta and mucosa of the rumen, cecum, and colon of the cashmere goat from birth to adulthood to compare its spatiotemporal difference via 16S rRNA gene sequencing. A total of 1,003 genera belonging to 43 phyla were identified. Principal coordinate analysis unveiled the similarity of microbial community between or within each age group increased and gradually developed toward mature whatever in digesta or mucosa. In the rumen, the composition of the bacterial community in digesta differed significantly from in mucosa across age groups; whereas in the hindgut, there was a high similarity of bacterial composition between the in digesta and mucosa in each age group before weaning, while the bacterial community structure differed markedly between these two types of samples after weaning. Taxonomic analysis indicated that 25 and 21 core genera coexisted in digesta and mucosa of the rumen and hindgut, respectively; but their abundances differed considerably by GIT region and/or age. In digesta, as goats aged, a lower abundance of Bacillus was observed with higher abundances of Prevotella 1 and Rikenellaceae RC9 in the rumen; while in the hindgut, the genera Escherichia-Shigella, Variovorax, and Stenotrophomonas decreased and Ruminococcaceae UCG-005, Ruminococcaceae UCG-010, and Alistipes increased with age increased. In mucosa, the rumen showed microbial dynamics with increases of Butyrivibrio 2 and Prevotellaceae UCG-001 and decreases of unclassified_f_Pasteurellaceae; while the genera Treponema 2 and Ruminococcaceae UCG-010 increased and Escherichia-Shigella decreased in the hindgut as goats aged. These results shed light on the colonization process of microbiota in the rumen and hindgut, which mainly include the initial, transit, and mature phases. Furthermore, there is a significant difference in the microbial composition between in digesta and mucosa, and both these exhibit a considerable spatiotemporal specificity.
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Porcine epidemic diarrhea virus (PEDV) is an enteric coronavirus that causes acute diarrhea, vomiting, dehydration, and a high mortality rate in neonatal piglets. In recent years, PEDV has been associated with co-infections with other swine enteric viruses, including porcine rotavirus (PoRV), resulting in increased mortality among newborn piglets. In this paper, we developed a bivalent vaccine against PEDV and PoRV by constructing a recombinant PEDV encoding PoRV VP7 (rPEDV-PoRV-VP7). The recombinant virus was constructed by replacing the entire open reading frame 3 (ORF3) in the genome of an attenuated PEDV strain YN150 with the PoRV VP7 gene using reverse genetic systems. Similar plaque morphology and replication kinetics were observed in Vero cells with the recombinant PEDV compared to the wild-type PEDV. It is noteworthy that the VP7 protein could be expressed stably in rPEDV-PoRV-VP7-infected cells. To evaluate the immunogenicity and safety of rPEDV-PoRV-VP7, 10-day-old piglets were vaccinated with the recombinant virus. After inoculation, no piglet displayed clinical symptoms such as vomiting, diarrhea, or anorexia. The PoRV VP7- and PEDV spike-specific IgG in serum and IgA in saliva were detected in piglets after rPEDV-PoRV-VP7 vaccination. Moreover, both PoRV and PEDV neutralizing antibodies were produced simultaneously in the inoculated piglets. Collectively, we engineered a recombinant PEDV expressing PoRV VP7 that could be used as an effective bivalent vaccine against PEDV and PoRV.
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Infecções por Coronavirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Animais , Chlorocebus aethiops , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/veterinária , Diarreia/prevenção & controle , Diarreia/veterinária , Vírus da Diarreia Epidêmica Suína/genética , Rotavirus , Suínos , Vacinas Combinadas , Células Vero , VômitoRESUMO
Aiming to determine the geometric and acoustic parameters of inhomogeneous multi-layer coatings, an ultrasonic pressure reflection coefficient amplitude spectrum (URCAS) is derived using a material-oriented regularization scheme, when wave propagates perpendicularly to the coating surface. Based on the derived theoretical URCAS, a new objective function combining least-squares and cross-correlation algorithm is developed to simultaneously identify the thickness, sound velocity, density, attenuation coefficient amplitude, and attenuation coefficient power-law of the multi-layer coating. Genetic algorithm with the constraint of total multi-layer coating thickness being known is presented to optimize the nonlinear objective function for obtaining global optimal solution. Ultrasonic experiments were implemented on a dual-layer coating specimen with coating1/coating2/substrate structure using a flat immersion transducer with a central frequency of 15 MHz. The inversed thicknesses, sound velocities, and densities of the dual-layer coating were in good agreement with those measured through other methods, with less than 8.1% errors. The inversed attenuation coefficients of the coating 1 and coating 2 were α(f) = 1.02e-2 × f1.93 and α(f) = 4.62e-3 × f1.97, respectively. The upper bounds of the relative errors +r of inverted parameters were all less than 0.061. The proposed ultrasonic inversion method could be used to quantitatively characterize the surface integrity of inhomogeneous multi-layer coatings.
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SnS2 with high theoretical capacity has been impeded from practical applications as the anode of lithium-ion (Li-ion) batteries due to its large volume expansion and fast capacity decay. A nanostructure of the SnS2 semifilled carbon nanotube (SnS2@CNT) has been realized by plasma-assisted fabrication of Sn semifilled CNT (Sn@CNT) followed by post-sulfurization. When serving as the anode of a Li-ion battery, SnS2@CNT delivers an initial discharge capacity of 1258 mAh g-1 at 0.3 A g-1. Instead of capacity fading, SnS2@CNT shows inverse capacity growth to 2733 mAh g-1 after 470 cycles. The high-resolution transmission electron microscopy images show that the void in CNTs, after cycling, is fully filled with pulverized SnS2 grains which have a shortened Li-ion diffusion path and enhanced surface area for interfacial redox reactions. In addition, the CNTs, like a pocket, confine the pulverized SnS2, maintain the electric contact and structural integrity, and thus allow the electrodes to work safely under long cyclic loadings and extreme temperature conditions.
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The boundary-value problem for a Dyakonov-Tamm wave guided by a twist defect in a structurally chiral material and propagating along the bisector of the twist defect was formulated. The resulting dispersion equation was numerically solved. Detailed analysis showed that either two or three different Dyakonov-Tamm waves can propagate, depending on the value of the twist angle. These waves have different phase speeds and degrees of localization to the twist-defect interface.
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Series of novel broad excitation band phosphors M2 MgSis O7 : Eu, Dy(M = Ca, Sr) were prepared by a high temperature solid-state reaction method. The crystal structure of compound was characterized. And the effects of part substitution of alkaline-earth on crystal structure, photoluminescence spectra and luminescence properties were also investigated. It is found that the excitation band of silicate luminescent materials extend to visible region and they exhibit yellow, green and blue long after-glow luminescence after excited by ultraviolet or visible light. Ca MgSi O7 : Eu, Dy luminescent materials can be excited effectively under the 450-480 nm range and exhibit a strong emission at 536 nm, nicely combining with blue light emitted by InGaN chips to produce white light. This promises the silicate luminescent materials a potential yellow phosphor for white LED.
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The green up-conversion emissions centered at the wavelengths of about 534nmand 549nm of the Er3+ doped silicate glass were recorded, using a 978 nm semiconductorlaser diode (LD) as an excitation source. The fluorescence intensity ratio (FIR) of the greenup-conversion emissions at about 534nm and 549nm in the Er3+ doped silicate glass wasstudied as a function of temperature over the temperature range of 296K-673K. Themaximum sensitivity and the temperature resolution derived from the FIR of the green up-conversion emissions are approximately 0.0023K-1 and 0.8K, respectively. It isdemonstrated that the prototype optical temperature sensor based on the FIR technique fromthe green up-conversion emissions in the Er3+ doped silicate glass could play a major role intemperature measurement.