The influence of excessive consumption on residents’ family thriving: the roles of intergenerational poverty transmission and educational cognition

Whether excessive consumption triggers the intergenerational transmission of poverty, as well as the role of residents’ cognition in family thriving, is still unclear in the literature. By adopting the structural equation model and the hierarchical regression method, we empirically tested the impact of excessive consumption and intergenerational transmission of poverty on the family thriving. We found that: first, the stronger the excessive consumption of Chinese residents are, the less helpful for them to achieve family thriving; the stronger the intra- and inter-generational transmission of poverty of Chinese residents are, the less likely for them to achieve family thriving. Second, excessive consumption reduces residents’ demands on family thriving by promoting the degree of intra-generational or inter-generational transmission of poverty. Third, the effect of achieving family thriving by reducing the intra- or inter-intergenerational transmission of poverty is evident in highly education-cognitive people. Our research provides insight into how excessive consumption affects the intergenerational transmission of poverty and the family thriving. It also provides valuable decision support for poverty reduction in public sector

FABP4-mediated lipid droplet formation in Streptococcus uberis-infected macrophages supports host defence

Foamy macrophages containing prominent cytoplasmic lipid droplets (LDs) are found in a variety of infectious diseases. However, their role in Streptococcus uberis-induced mastitis is unknown. Herein, we report that S. uberis infection enhances the fatty acid synthesis pathway in macrophages, resulting in a sharp increase in LD levels, accompanied by a significantly enhanced inflammatory response. This process is mediated by the involvement of fatty acid binding protein 4 (FABP4), a subtype of the fatty acid-binding protein family that plays critical roles in metabolism and inflammation. In addition, FABP4 siRNA inhibitor cell models showed that the deposition of LDs decreased, and the mRNA expression of Tnf, Il1b and Il6 was significantly downregulated after gene silencing. As a result, the bacterial load in macrophages increased. Taken together, these data demonstrate that macrophage LD formation is a host-driven component of the immune response to S. uberis. FABP4 contributes to promoting inflammation via LDs, which should be considered a new target for drug development to treat infections

Taurine reprograms mammary-gland metabolism and alleviates inflammation induced by Streptococcus uberis in mice

Streptococcus uberis (S. uberis) is an important pathogen causing mastitis, which causes continuous inflammation and dysfunction of mammary glands and leads to enormous economic losses. Most research on infection continues to be microbial metabolism-centric, and many overlook the fact that pathogens require energy from host. Mouse is a common animal model for studying bovine mastitis. In this perspective, we uncover metabolic reprogramming during host immune responses is associated with infection-driven inflammation, particularly when caused by intracellular bacteria. Taurine, a metabolic regulator, has been shown to effectively ameliorate metabolic diseases. We evaluated the role of taurine in the metabolic regulation of S. uberis-induced mastitis. Metabolic profiling indicates that S. uberis exposure triggers inflammation and metabolic dysfunction of mammary glands and mammary epithelial cells (the main functional cells in mammary glands). Challenge with S. uberis upregulates glycolysis and oxidative phosphorylation in MECs. Pretreatment with taurine restores metabolic homeostasis, reverses metabolic dysfunction by decrease of lipid, amino acid and especially energy disturbance in the infectious context, and alleviates excessive inflammatory responses. These outcomes depend on taurine-mediated activation of the AMPK–mTOR pathway, which inhibits the over activation of inflammatory responses and alleviates cellular damage. Thus, metabolic homeostasis is essential for reducing inflammation. Metabolic modulation can be used as a prophylactic strategy against mastitis

Allelic Variation Contributes to Bacterial Host Specificity

Understanding the molecular parameters that regulate cross-species transmission and host adaptation of potential pathogens is crucial to control emerging infectious disease. Although microbial pathotype diversity is conventionally associated with gene gain or loss, the role of pathoadaptive nonsynonymous single-nucleotide polymorphisms (nsSNPs) has not been systematically evaluated. Here, our genome-wide analysis of core genes within Salmonella enterica serovar Typhimurium genomes reveals a high degree of allelic variation in surface-exposed molecules, including adhesins that promote host colonization. Subsequent multinomial logistic regression, MultiPhen and Random Forest analyses of known/suspected adhesins from 580 independent Typhimurium isolates identifies distinct host-specific nsSNP signatures. Moreover, population and functional analyses of host-associated nsSNPs for FimH, the type 1 fimbrial adhesin, highlights the role of key allelic residues in host-specific adherence in vitro. Together, our data provide the first concrete evidence that functional differences between allelic variants of bacterial proteins likely contribute to pathoadaption to diverse hosts

Identification of the Genes Involved in Riemerella anatipestifer Biofilm Formation by Random Transposon Mutagenesis

Riemerella anatipestifer causes epizootics of infectious disease in poultry that result in serious economic losses to the duck industry. Our previous studies have shown that some strains of R. anatipestifer can form a biofilm, and this may explain the intriguing persistence of R. anatipestifer on duck farms post infection. In this study we used strain CH3, a strong producer of biofilm, to construct a library of random Tn4351 transposon mutants in order to investigate the genetic basis of biofilm formation by R. anatipestifer on abiotic surfaces. A total of 2,520 mutants were obtained and 39 of them showed a reduction in biofilm formation of 47%–98% using crystal violet staining. Genetic characterization of the mutants led to the identification of 33 genes. Of these, 29 genes are associated with information storage and processing, as well as basic cellular processes and metabolism; the function of the other four genes is currently unknown. In addition, a mutant strain BF19, in which biofilm formation was reduced by 98% following insertion of the Tn4351 transposon at the dihydrodipicolinate synthase (dhdps) gene, was complemented with a shuttle plasmid pCP-dhdps. The complemented mutant strain was restored to give 92.6% of the biofilm formation of the wild-type strain CH3, which indicates that the dhdp gene is associated with biofilm formation. It is inferred that such complementation applies also to other mutant strains. Furthermore, some biological characteristics of biofilm-defective mutants were investigated, indicating that the genes deleted in the mutant strains function in the biofilm formation of R. anatipestifer. Deletion of either gene will stall the biofilm formation at a specific stage thus preventing further biofilm development. In addition, the tested biofilm-defective mutants had different adherence capacity to Vero cells. This study will help us to understand the molecular mechanisms of biofilm development by R. anatipestifer and to study the pathogenesis of R. anatipestifer further

Development of an allele-specific PCR assay for simultaneous sero-typing of avian pathogenic Escherichia coli predominant O1, O2, O18 and O78 strains.

Systemic infections by avian pathogenic Escherichia coli (APEC) are economically devastating to poultry industries worldwide. E. coli strains belonging to serotypes O1, O2, O18 and O78 are preferentially associated with avian colibacillosis. The rfb gene cluster controlling O antigen synthesis is usually various among different E. coli serotypes. In present study, the rfb gene clusters of E. coli serotypes O1, O2, O18 and O78 were characterized and compared. Based on the serotype-specific genes in rfb gene cluster, an allele-specific polymerase chain reaction (PCR) assay was developed. This PCR assay was highly specific and reliable for sero-typing of APEC O1, O2, O18 and O78 strains. The sensitivity of the assay was determined as 10 pg DNA or 10 colony forming units (CFUs) bacteria for serotypes O2 and O18 strains, and 500 pg DNA or 1,000 CFUs bacteria for serotypes O1 and O78 strains. Using this PCR system, APEC isolates and the infected tissue samples were categorized successfully. Furthermore, it was able to differentiate the serotypes for the samples with multi-agglutination in the traditional serum agglutination assay. Therefore, the allele-specific PCR is more simple, rapid and accurate assay for APEC diagnosis, epidemiologic study and vaccine development

Immunolocation and enzyme activity analysis of Cryptosporidium parvum enolase

Abstract Background Enolase is an essential multifunctional glycolytic enzyme that is involved in many biological processes of apicomplexan protozoa, such as adhesion and invasion. However, the characteristics of enolase in Cryptosporidium parvum, including the location on the oocyst and the enzyme activity, remain unclear. Methods The C. parvum enolase gene (cpeno) was amplified by RT-PCR and sequenced. The deduced amino acid sequence was analysed by bioinformatics software. The gene was expressed in Escherichia coli BL21 (DE3) and purified recombinant protein was used for enzyme activity analysis, binding experiments and antibody preparation. The localisation of enolase on oocysts was examined via immunofluorescence techniques. Results A 1,350 bp DNA sequence was amplified from cDNA taken from C. parvum oocysts. The deduced amino acids sequence of C. parvum enolase (CpEno) had 82.1% homology with Cryptosporidium muris enolase, and 54.7–68.0% homology with others selected species. Western blot analysis indicated that recombinant C. parvum enolase (rCpEno) could be recognised by C. parvum-infected cattle sera. Immunolocalization testing showed that CpEno was found to locate mainly on the surface of oocysts. The enzyme activity was 33.5 U/mg, and the Michaelis constant (K m ) was 0.571 mM/l. Kinetic measurements revealed that the most suitable pH value was 7.0–7.5, and there were only minor effects on the activity of rCpEno with a change in the reaction temperature. The enzyme activity decreased when the Ca2+, K+, Mg2+ and Na+ concentrations of the reaction solution increased. The binding assays demonstrated that rCpEno could bind to human plasminogen. Conclusion This study is the first report of immunolocation, binding activity and enzyme characteristics of CpEno. The results of this study suggest that the surface-associated CpEno not only functions as a glycolytic enzyme but may also participate in attachment and invasion process of the parasite

TLR2 Signaling Pathway Combats Streptococcus uberis Infection by Inducing Mitochondrial Reactive Oxygen Species Production

Mastitis caused by Streptococcus uberis (S. uberis) is a common and difficult-to-cure clinical disease in dairy cows. In this study, the role of Toll-like receptors (TLRs) and TLR-mediated signaling pathways in mastitis caused by S. uberis was investigated using mouse models and mammary epithelial cells (MECs). We used S. uberis to infect mammary glands of wild type, TLR2−/− and TLR4−/− mice and quantified the adaptor molecules in TLR signaling pathways, proinflammatory cytokines, tissue damage, and bacterial count. When compared with TLR4 deficiency, TLR2 deficiency induced more severe pathological changes through myeloid differentiation primary response 88 (MyD88)-mediated signaling pathways during S. uberis infection. In MECs, TLR2 detected S. uberis infection and induced mitochondrial reactive oxygen species (mROS) to assist host in controlling the secretion of inflammatory factors and the elimination of intracellular S. uberis. Our results demonstrated that TLR2-mediated mROS has a significant effect on S. uberis-induced host defense responses in mammary glands as well as in MECs

Seroepidemiological study of canine Leishmania infantum and Toxoplasma gondii infections in Shanghai, China, and analysis of risk factors

The aim of this study was to determine the seroprevalence of Leishmania infantum and Toxoplasma gondii among household dogs in Shanghai (the most important industrial and commercial city in China), and to assess the possible risk factors associated with the infection. During 2014–2015, a total of 408 sera were collected from healthy household dogs and tested for L. infantum and T. gondii infection using commercial ELISA kits. The endemic characteristics according to gender, age group and breed were revealed by statistical descriptions and inference. The positive rates of L. infantum[ infection (24/408, 5.9%) were lower than those of T. gondii infection (37/408, 9.1%), and co-infection with both parasites was detected in seven dogs (7/408, 1.7%). Seropositivity for either parasite was more likely associated with age: the seroprevalence of T. gondii infection ranged from 1.3% (dogs≤1 year) – 18.7% (dogs>6 years), whereas that of L. infantum ranged from 1.3% (dogs≤1 year) – 9.9 % (dogs>6 years). Interestingly, the rates of exposure to both L. infantum and T. gondii were higher in males than in females. Relatively higher exposure rates for L. infantum and T. gondii were also observed in crossbred dogs compared with purebred dogs. However, neither gender nor breed is likely a determining factor for infection with these two parasites (P>0.05). Identification of the risk factors that underlie these differences may help in the prevention of L. infantum and T. gondii infection in household dogs. To the best of our knowledge, this is the first report of L. infantum and T. gondii infection in household dogs in Shanghai, which shows that these two important parasites are still prevalent in this region. Therefore, it is necessary to take integrated strategies for prevention and control of infection in animals, which could help to reduce human infection in the region

Development of a novel oil-in-water emulsion and evaluation of its potential adjuvant function in a swine influenza vaccine in mice

Abstract Background Vaccination is the principal strategy for prevention and control of diseases, and adjuvant use is an effective strategy to enhance vaccine efficacy. Traditional mineral oil-based adjuvants have been reported with post-immunization reactions. Developing new adjuvant formulations with improved potency and safety will be of great value. Results In the study reported herein, a novel oil-in-water (O/W) Emulsion Adjuvant containing Squalane (termed EAS) was developed, characterized and investigated for swine influenza virus immunization. The data show that EAS is a homogeneous nanoemulsion with small particle size (~ 105 nm), low viscosity (2.04 ± 0.24 cP at 20 °C), excellent stability (at least 24 months at 4 °C) and low toxicity. EAS-adjuvanted H3N2 swine influenza vaccine was administrated in mice subcutaneously to assess the adjuvant potency of EAS. The results demonstrated that in mice EAS-adjuvanted vaccine induced significantly higher titers of hemagglutination inhibition (HI) and IgG antibodies than water-in-oil (W/O) vaccines or antigen alone, respectively, at day 42 post vaccination (dpv) (P < 0.05). EAS-adjuvanted vaccine elicited significantly stronger IgG1 and IgG2a antibodies and higher concentrations of Th1 (IFN-γ and IL-2) cytokines compared to the W/O vaccine or antigen alone. Mice immunized with EAS-adjuvanted influenza vaccine conferred potent protection after homologous challenge. Conclusion The O/W emulsion EAS developed in the present work induced potent humoral and cellular immune responses against inactivated swine influenza virus, conferred effective protection after homologous virus challenge and showed low toxicity in mice, indicating that EAS is as good as the commercial adjuvant MF59. The superiority of EAS to the conventional W/O formulation in adjuvant activity, safety and stability will make it a potential veterinary adjuvant