157 research outputs found
Reactive oxygen species promote chloroplast dysfunction and salicylic acid accumulation in fumonisin B1-induced cell death
AbstractWe report a novel regulatory mechanism by which reactive oxygen species (ROS) regulate fumonisin B1 (FB1)-induced cell death. We found that FB1 induction of light-dependent ROS production promoted the degradation of GFP-labeled chloroplast proteins and increased phenylalanine ammonia lyase (PAL) activity, PAL1 gene expression and SA content, while pretreatment with ROS manipulators reversed these trends. Moreover, treatment with H2O2 or 3-amino-1,2,4-triazole increased PAL activity, PAL1 gene expression and SA content. PAL inhibitor significantly blocked FB1-induced lesion formation and SA increase. Our results demonstrate that light-dependent ROS accumulation stimulates the degradation of chloroplastic proteins and up-regulates PAL-mediated SA synthesis, thus promoting FB1-induced light-dependent cell death
Vesicular glutamatergic transmission in noise-induced loss and repair of cochlear ribbon synapses
Noise-induced excitotoxicity is thought to depend on glutamate. However, the excitotoxic mechanisms are unknown, and the necessity of glutamate for synapse loss or regeneration is unclear. Despite absence of glutamatergic transmission from cochlear inner hair cells in mice lacking the vesicular glutamate transporter-3
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Environmental Stewardship: How Semiconductor Suppliers Help to Meet Energy-Efficiency Regulations and Voluntary Specifications in China
Recognizing the role that semiconductor suppliers can playin meeting energy-efficiency regulations and voluntary specifications,this paper provides an overview of Chinese policies and implementingbodies; a discussion of current programs, their goals, and effectiveness;and possible steps that can be taken tomeet these energy-efficiencyrequirements while also meeting products' high performance and costgoals
Isolation of Mycobacterium tuberculosis complex (MTBC) from dairy cows in China
Eleven thousand five hundred and eighty non-blood samples from dairy cows were subjected to mycobacterium culture and genotyping. As a result, a total of 142 isolates of Mycobacterium tuberculosis complex (MBTC) were identified. Among them, 65 were Mycobacterium tuberculosis, while 77 Mycobacterium bovis. The genotype of M. tuberculosis strains was mainly Beijing family. In addition, the isolation rates of MTBC were 33.89% for lung lymph nodes, 2.81% for nasal swabs, and 3.95% for pharyngeal swabs from cattle positive to tuberculin skin test, respectively. This evidence implied that M. tuberculosis infection in cattle is a new risk to public health and should be paid more attention.Key words: Mycobacterium tuberculosis complex, cows, tuberculosis, zoonosis
An atypical GdpP enzyme linking cyclic nucleotide metabolism to osmotic tolerance and gene regulation in Mycoplasma bovis
Nucleotide second messengers play an important role in bacterial adaptation to environmental changes. Recent evidence suggests that some of these regulatory molecular pathways were conserved upon the degenerative evolution of the wall-less mycoplasmas. We have recently reported the occurrence of a phosphodiesterase (PDE) in the ruminant pathogen Mycoplasma bovis, which was involved in c-di-AMP metabolism. In the present study, we demonstrate that the genome of this mycoplasma species encodes a PDE of the GdpP family with atypical DHH domains. Characterization of M. bovis GdpP (MbovGdpP) revealed a multifunctional PDE with unusual nanoRNase and single-stranded DNase activities. The alarmone ppGpp was found unable to inhibit c-di-NMP degradation by MbovGdpP but efficiently blocked its nanoRNase activity. Remarkably, MbovGdpP was found critical for the osmotic tolerance of M. bovis under K+ and Na+ conditions. Transcriptomic analyses further revealed the biological importance of MbovGdpP in tRNA biosynthesis, pyruvate metabolism, and several steps in genetic information processing. This study is an important step in understanding the role of PDE and nucleotide second messengers in the biology of a minimal bacterial pathogen
Snoring, Inflammatory Markers, Adipokines and Metabolic Syndrome in Apparently Healthy Chinese
OBJECTIVE: Chronic low-grade inflammation and adipokines dysregulation are linked to mechanisms underscoring the pathogenesis of obesity-related metabolic disorders. Little is known about roles of these cytokines on the association between snoring and metabolic syndrome (MetS). We aimed to investigate whether a cluster of cytokines are related to snoring frequency and its association with MetS in apparently healthy Chinese. METHODS: Current analyses used a population-based sample including 1059 Shanghai residents aged 35-54 years. Self-reported snoring frequency was classified as never, occasionally and regularly. Fasting plasma glucose, lipid profile, insulin, C-reactive protein, interleukin-6, interleukin-18, lipopolysaccharide binding protein, high-molecular-weight adiponectin and leptin were measured. MetS was defined by the updated National Cholesterol Education Program Adult Treatment Panel III criteria for Asian-Americans. RESULTS: Overweight/obese subjects had significantly higher prevalence of regular snorers than their normal-weight counterparts (34.8% vs. 11.5%, P<0.001). Regular snoring was associated with unfavorable profile of inflammatory markers and adipokines. However, those associations were abolished after adjustment for body mass index (BMI) or waist circumference. The MetS risk (multivariate-adjusted odds ratio 5.41, 95% confidence interval 3.72-7.88) was substantially higher in regular snorers compared with non-snorers. Controlling for BMI remarkably attenuated the association (2.03, 1.26-3.26), while adjusting for inflammatory markers and adipokines showed little effects. CONCLUSION: Frequent snoring was associated with an elevated MetS risk independent of lifestyle factors, adiposity, inflammatory markers and adipokines in apparently healthy Chinese. Whether snoring pattern is an economic and no-invasive indicator for screening high-risk persons needs to be addressed prospectively
C500 variants conveying complete mucosal immunity against fatal infections of pigs with Salmonella enterica serovar Choleraesuis C78-1 or F18+ Shiga toxin-producing Escherichia coli
Salmonella enterica serovar Choleraesuis (S. Choleraesuis) C500 strain is a live, attenuated vaccine strain that has been used in China for over 40 years to prevent piglet paratyphoid. However, this vaccine is limited by its toxicity and does not offer protection against diseases caused by F18+ Shiga toxin-producing Escherichia coli (STEC), which accounts for substantial economic losses in the swine industry. We recently generated a less toxic derivative of C500 strain with both asd and crp deletion (S. Choleraesuis C520) and assessed its efficacy in mice. In addition, we demonstrate that C520 is also less toxic in pigs and is effective in protecting pigs against S. Choleraesuis when administered orally. To develop a vaccine with a broader range of protection, we prepared a variant of C520 (S. Choleraesuis C522), which expresses rSF, a fusion protein comprised of the fimbriae adhesin domain FedF and the Shiga toxin-producing IIe B domain antigen. For comparison, we also prepared a control vector strain (S. Choleraesuis C521). After oral vaccination of pigs, these strains contributed to persistent colonization of the intestinal mucosa and lymphoid tissues and elicited both cytokine expression and humoral immune responses. Furthermore, oral immunization with C522 elicited both S. Choleraesuis and rSF-specific immunoglobulin G (IgG) and IgA antibodies in the sera and gut mucosa, respectively. To further evaluate the feasibility and efficacy of these strains as mucosal delivery vectors via oral vaccination, we evaluated their protective efficacy against fatal infection with S. Choleraesuis C78-1, as well as the F18+ Shiga toxin-producing Escherichia coli field strain Ee, which elicits acute edema disease. C521 conferred complete protection against fatal infection with C78-1; and C522 conferred complete protection against fatal infection with both C78-1 and Ee. Our results suggest that C520, C521, and C522 are competent to provide complete mucosal immune protection against fatal infection with S. Choleraesuis in swine and that C522 equally qualifies as an oral vaccine vector for protection against F18+ Shiga toxin-producing Escherichia coli
Nomenclatural and taxonomic notes on Rubus davidianus Kuntze and R. viburnifolius Franch
Critical examinations of specimens, with literature reviews, have shown that Rubus davidianus is conspecific with R. lambertianus. Therefore, we treat R. davidianus as a new synonym within Rubus. We propose a new name, Rubus loirensis Ti R. Huang nom. nov. to replace the later homonym of R. pycnanthus Genev. Additionally, lectotypification of three names, R. davidianus Kuntze, R. malifolius Focke and R. viburnifolius Franch., are designated here after examination of previous works
Comparative Geno-Plasticity Analysis of Mycoplasma bovis HB0801 (Chinese Isolate)
Mycoplasma bovis pneumonia in cattle has been epidemic in China since 2008. To investigate M. bovis pathogenesis, we completed genome sequencing of strain HB0801 isolated from a lesioned bovine lung from Hubei, China. The genomic plasticity was determined by comparing HB0801 with M. bovis strain ATCC® 25523™/PG45 from cow mastitis milk, Chinese strain Hubei-1 from lesioned lung tissue, and 16 other Mycoplasmas species. Compared to PG45, the genome size of HB0801 was reduced by 11.7 kb. Furthermore, a large chromosome inversion (580 kb) was confirmed in all Chinese isolates including HB0801, HB1007, a strain from cow mastitis milk, and Hubei-1. In addition, the variable surface lipoproteins (vsp) gene cluster existed in HB0801, but contained less than half of the genes, and had poor identity to that in PG45, but they had conserved structures. Further inter-strain comparisons revealed other mechanisms of gene acquisition and loss in HB0801 that primarily involved insertion sequence (IS) elements, integrative conjugative element, restriction and modification systems, and some lipoproteins and transmembrane proteins. Subsequently, PG45 and HB0801 virulence in cattle was compared. Results indicated that both strains were pathogenic to cattle. The scores of gross pathological assessment for the control group, and the PG45- and HB0801-infected groups were 3, 13 and 9, respectively. Meanwhile the scores of lung lesion for these three groups were 36, 70, and 69, respectively. In addition, immunohistochemistry detection demonstrated that both strains were similarly distributed in lungs and lymph nodes. Although PG45 showed slightly higher virulence in calves than HB0801, there was no statistical difference between the strains (P>0.05). Compared to Hubei-1, a total of 122 SNP loci were disclosed in HB0801. In conclusion, although genomic plasticity was thought to be an evolutionary advantage, it did not apparently affect virulence of M. bovis strains in cattle
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