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Salmonella is a rod-shaped, Gram-negative zoonotic pathogen that poses a serious global socioeconomic and public health threat. Rapid and accurate detection of Salmonella spp. is critical for effective control of its infection. In this study, an accurate, sensitive and specific graphene oxide-assisted accelerated strand exchange amplification (GO-ASEA) method for rapid detection of Salmonella spp. was developed and validated. The detection limit of the GO-ASEA method was 8.6 × 10

An accurate, rapid and highly sensitive graphene oxide-based accelerated strand exchange amplification method was developed for quantitative detection of African swine fever virus (ASFV).

The aim of this study was to investigate the effects and potential signaling pathway of selenium-enriched Bacillus subtilis (SEBS) on beta defensin 1 (BD1) expression in chicken intestine. Chinese Huainan Partridge chickens (500 individuals) were randomly allocated into five groups, including control, inorganic Se, B. subtilis, SEBS, and a mixture of Se and B. subtilis (Se-BS). After 56 d of feeding, chicken ileal mucous membranes were harvested to detect differences in expression of BD1. The results indicated that BD1 was produced in intestinal crypt cells and secreted into the lumen through the villi brush border. BD1 was up-regulated in distal ileum segments colonized by SEBS and B. subtilis. Chicken primary intestinal crypt cells were cultured and grouped into control, inorganic Se, B. subtilis, SEBS, and Se-BS treatments to identify the receptor of B. subtilis. Results indicated that B. subtilis and SEBS were recognized by toll-like receptor 2 (TLR2), stimulating the NF-κB1 signaling pathway to increase expression of BD-1, which was further enhanced when combined with Se. Pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 were up-regulated with B. subtilis supplementation, and inhibited under the action of Se. In conclusion, B. subtilis and SEBS were recognized by the TLR2 receptor in the ileal mucous membrane, which activated the TLR2-MyD88-NF-κB1 signaling pathway to upregulate BD1 expression. In addition, Se enhanced recognition of B. subtilis and reduced levels of pro-inflammatory factors caused by estrogenic B. subtilis supplementation.

To investigate the therapeutic effect of adipose-derived stem cells (ADSCs) on chronic kidney disease (CKD) in dogs, blood routine examination, urine protein quantitative test, renal function test, urine sediment staining microscopy and B-ultrasonic test of kidney were used to compare the treatment of chronic kidney disease in dogs treated with three different therapies (NT treatment group: traditional supportive therapy group; MT1 treatment group: ADSCs treatment group; MT2 treatment group: NT mixed MT1 treatment group). Results showed that the numbers of red blood cells (RBC), hemoglobin (HGB) and hematocrit (HCT) in MT1 and MT2 treatment groups were higher than those in the NT group, and the urine protein excretion and the levels of serum urea and creatinine in MT1 and MT2 treatment groups were lower than those in the NT treatment group. Besides, there was no further deterioration of kidney morphology in MT1 and MT2 treatment groups. However, a large number of renal tubular epithelial cells and epithelial casts were observed in NT treatment group, while only a small number of renal tubular epithelial cells were observed in MT1 and MT2 treatment groups, indicating the intravenous injection of ADSCs can significantly improve the physical signs and renal function of dogs with CKD, and combined with the traditional therapy, ADSCs has a good prospect for the treatment of CKD in dogs.

Here, a Selenium-enriched Bacillus subtilis (SEBS) strain was generated and supplemented to broiler chickens’ diet, and the impact in ileum bacterial microbiome, immunity and body weight were assessed. In a nutshell, five hundred 1-old old chicken were randomly divided into five groups: control, inorganic Se, Bacillus subtilis (B. subtilis), SEBS, and antibiotic, and colonization with B. subtilis and SEBS in the gastrointestinal tract (GIT) were measured by fluorescence in situ hybridization (FISH) assay and quantitative real-time polymerase chain reaction (qPCR). In summary, Chicks fed SEBS or B. subtilis had higher body weight than the control chicks or those given inorganic Se. SEBS colonized in distal segments of the ileum improved bacterial diversity, reduced the endogenous pathogen burden and increased the number of Lactobacillus sp. in the ileal mucous membrane. Species of unclassified Lachnospiraceae, uncultured Anaerosporobacter, Peptococcus, Lactobacillus salivarius, and Ruminococcaceae_UCG-014, and unclassified Butyricicoccus in the ileal mucous membrane played a key role in promoting immunity. Inorganic Se supplementation also improved bacterial composition of ileal mucous membranes, but to a less extent. In conclusion, SEBS improved performance and immunity of broiler chickens through colonization and modulation of the ileal mucous membrane microbiome.

The aim of this study was to investigate the effects and potential signaling pathway of selenium-enriched Bacillus subtilis (SEBS) on beta defensin 1 (BD1) expression in chicken intestine. Chinese Huainan Partridge chickens (500 individuals) were randomly allocated into five groups, including control, inorganic Se, B. subtilis, SEBS, and a mixture of Se and B. subtilis (Se-BS). After 56 d of feeding, chicken ileal mucous membranes were harvested to detect differences in expression of BD1. The results indicated that BD1 was produced in intestinal crypt cells and secreted into the lumen through the villi brush border. BD1 was up-regulated in distal ileum segments colonized by SEBS and B. subtilis. Chicken primary intestinal crypt cells were cultured and grouped into control, inorganic Se, B. subtilis, SEBS, and Se-BS treatments to identify the receptor of B. subtilis. Results indicated that B. subtilis and SEBS were recognized by toll-like receptor 2 (TLR2), stimulating the NF-κB1 signaling pathway to increase expression of BD-1, which was further enhanced when combined with Se. Pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 were up-regulated with B. subtilis supplementation, and inhibited under the action of Se. In conclusion, B. subtilis and SEBS were recognized by the TLR2 receptor in the ileal mucous membrane, which activated the TLR2-MyD88-NF-κB1 signaling pathway to upregulate BD1 expression. In addition, Se enhanced recognition of B. subtilis and reduced levels of pro-inflammatory factors caused by estrogenic B. subtilis supplementation.

In decades, Pseudanabaena species have been frequently reported as cyanobacterial bloom components. However, these species are always overlooked because they cannot be observed easily owing to their small sizes. This study aimed to characterize Pseudanabaena species and detect them in field waters by developing an effective DNA marker. A region with approximately 600 bp in the rbcLX sequences was specific to Pseudanabaena species alone compared with other cyanobacterial genera. Therefore, new primers specific for Pseudanabaena were generated. By using this molecular tool, seasonal and spatial dynamics of Pseudanabaena populations of six sites in Lushui Reservoir, China were measured from July 2010 to August 2011. Pseudanabaena species existed in the reservoir throughout the year, and cell abundance ranged between 10(4) and 10(6) equivalent cells/L, with the peak at 8.07 x 10(6) equivalent cells/L The seasonal dynamics pattern of Pseudanabaena was similar to that of Microcystis but showed a slight lag at the transitional points of water temperature in the reservoir. (C) 2015 Elsevier Ltd. All rights reserved.

Lake Erhai is the second largest lake of Southwest China and an important drinking water source. The lake is currently defined as the preliminary stage of eutrophic states, but facing a serious threat with transfer into intensive eutrophication. The present study examined the dynamics of Microcystis blooms and toxic Microcystis in Lake Erhai during 2010, based on quantitative real-time PCR method using 16S rRNA gene specific for Microcystis and microcystin systhesis gene (mcy), and chemical analysis on microcystin (MC) concentrations. Total Microcystis cell abundance at 16 sampling sites were shown as an average of 1.7 × 10(7) cells l(-1) (1.3 × 10(2)-3.8 × 10(9) cells l(-1)). Microcystin LR (MC-LR) and microcystin RR (MC-RR) were the main variants. The strong southwesterly winds, anticlockwise circular flows and geographical characteristics of lake and phytoplankton community succession impacted the distribution patterns of Chl a and MC in the lake. The concentration of Chl a and MC and abundances of total Microsytis and MC-producing Microsystis (MCM) were shown to be positively correlated with pH, DO and TP, negatively correlated with SD, NO₃-N, TN/Chl a and TN/TP, and not correlated with NH₄-N, TN, dissolved total nitrogen (DTN) and water temperatures. When TN/TP decrease, Microcystis tended to dominate and MC concentrations tended to increase, suggesting that the "TN/TP rule" can be partially applied to explain the correlation between the cyanobacterial blooms and nutrients N and P only within a certain nutrient level. It is speculated that N and P nutrients and the associated genes (e.g., mcy) may jointly drive MC concentration and toxigenicity of Microcystis in Lake Erhai.

Six Limnothrix strains, isolated for the first time from a shallow eutrophic lake in central China, were taxonomically and phylogenetically evaluated by investigating their polyphasic characteristics, including morphological features, cellular ultrastructures, and 16S rRNA gene sequences. All the six strains were morphologically similar, and their trichomes were in average 1.7 μm wide and cells 4.0 μm long, and having small gas vesicles within cells, and therefore identified as Limnothrix planctonica (Woloszynska) Meffert. Cellular ultrastructures of them showed that peripheral thylakoids with 3–5 parallel layers were parietally distributed in the cells. The phylogenetic results based on the 16S rRNA gene sequences showed that all the Limnothrix strains, including the six in this study and those from the Genbank, formed two distinct clusters. The similarity in 16S rDNA sequences between these two clusters was lower than 90%, indicating that these Limnothrix strains belong to different genera. This is the first report on the morphology and phylogeny of L. planctonica strains, providing the new information on taxonomy of the genus Limnothrix.

The genus Planktothrix Anagnostidis et Komarek 1988 represents an important, water-bloom forming cyanobacterial group, and in recent years it has been found to occur in dense water blooms around China. In this study, genetic diversity and phylogeny of Planktothrix strains isolated from seventeen Chinese water bodies, based on 16S rRNA, rbcLX and rpoC1 genes, were investigated. These Planktothrix strains, all phycocyanin-containing, were morphologically classified into two groups as Planktothrix agardhii and Planktothrix mougeotii. However, phylogenetic analyses, based on the three gene regions, revealed that Planktothrix strains analyzed in this study were mainly divided into three clades, corresponding to P. agardhii, Planktothrix pseudagardhii, and A mougeotii respectively. The strains in the P. pseudagardhii clade were shown to be more genetically divergent, reflecting possible existence of cryptic species in the genus Planktothrix. (C) 2009 Elsevier B.V. All rights reserved.

Desertifilum, a filamentous cyanobacterial genus, was initially described from biological crusts in Thar crusts in India. In this study, we isolated a novel cyanobacterial strain (CHAB7200) from a alkaline pool in Zhejiang province, China. The strain showed an identical 16S rRNA gene sequence to Desertifilum tharense, but was distinctly different in cellular morphology, ultrastructure and ecology. In addition, the strain exhibited growth ability at different alkalinities during 4.5 ~ 54 g/L, and the optimum growth was shown at 1% salinity, indicating its stronger tolerance to wider range of alkalinities and salinities than D. tharense. Ecological niche is an important criterion used to separate and define cyanobacterial species. In this case, the strain was proposed as a novel cyanobacterial species, Desertifilum salkalinema. sp. nov.

Sequencing the environmental rRNA genes of Microcystis populations, such as by internal transcribed spacer (ITS), has been proven to provide a new insight into the genetic diversity of Microcystis in freshwater. In this study, a 19-month monitoring of Microcystis populations in a hyper-eutrophic pond in Wuhan city, China was conducted through molecular method by sequencing ITS fragments from the environmental DNA library. Three hundred twenty ITS genotypes of Microcystis in this pond were identified from a total of 563 sequences, thus exhibiting high genetic diversity of Microcystis in the pond. Dramatic changes and succession in ITS genotypes were also found during the survey period. Despite the absence of significant dominant ITS genotypes in the pond, several main genotypes were found to have been dominated for a short term. However, Microcystis ITS genotype patterns from 2007 to 2008 presented a complicated situation in this pond. The parsimony network (TCS) analysis showed that two groups were formed based on ITS genotypes.

Current cyanobacterial taxonomic studies are mainly performed through polyphasic characterization at the genus and/or species levels. In this study, eleven Pseudanabaena strains isolated in China were taxonomically and phylogenetically evaluated by investigating several characteristics, including morphological features, cellular ultrastructures, pigment composition, and 16S rRNA gene sequences. The strains were identified as four morphospecies, namely, Pseudanabaena mucicola , P. galeata , P. limnetica , and P. minima . The cellular ultrastructures of these species showed that peripheral thylakoids with 4‒8 parallel layers were parietally distributed. Phylogenetic results based on 16S rRNA gene sequences indicated that most of the Pseudanabaena strains used in this study, including the eleven from China and three Pseudanabaena catenata strains from GenBank, gathered into one large cluster that represents the core of the genus Pseudanabaena. Several Pseudanabaena species/strains that represent different extreme environments were phylogenetically located outside the main stream cluster and should be removed under the genus Pseudanabaena on the basis of the role of the main stream species. Limnothrix strains were divided into two clades, and the taxonomic solution for these clades was discussed. This study is the first to report on the morphology and phylogeny of Pseudanabaena species in China, providing new insights into the taxonomy of the genera Pseudanabaena and Limnothrix .