Advantages of growth and competitive ability of the invasive plant Solanum rostratum over two co-occurring natives and the effects of nitrogen levels and forms.

Introduction: Atmospheric nitrogen (N) deposition has often been considered as a driver of exotic plant invasions. However, most related studies focused on the effects of soil N levels, and few on those of N forms, and few related studies were conducted in the fields. Methods: In this study, we grew Solanum rostratum, a notorious invader in arid/semi-arid and barren habitats, and two coexisting native plants Leymus chinensis and Agropyron cristatum in mono- and mixed cultures in the fields in Baicheng, northeast China, and investigated the effects of N levels and forms on the invasiveness of S. rostratum. Results: Compared with the two native plants, S. rostratum had higher aboveground and total biomass in both mono- and mixed monocultures under all N treatments, and higher competitive ability under almost all N treatments. N addition enhanced the growth and competitive advantage of the invader under most conditions, and facilitated invasion success of S. rostratum. The growth and competitive ability of the invader were higher under low nitrate relative to low ammonium treatment. The advantages of the invader were associated with its higher total leaf area and lower root to shoot ratio compared with the two native plants. The invader also had a higher light-saturated photosynthetic rate than the two native plants in mixed culture (not significant under high nitrate condition), but not in monoculture. Discussion: Our results indicated that N (especially nitrate) deposition may also promote invasion of exotic plants in arid/semi-arid and barren habitats, and the effects of N forms and interspecific competition need to be taken into consideration when studying the effects of N deposition on invasion of exotic plants.

MiR-130/SNAP-25 axis regulate presynaptic alteration in anterior cingulate cortex involved in lead induced attention deficits.

Brain volume decrease in the anterior cingulate cortex (ACC) after lead (Pb) exposure has been linked to persistent impairment of attention behavior. However, the precise structural change and molecular mechanism for the Pb-induced ACC alteration and its contribution to inattention have yet to be fully characterized. The present study determined the role of miRNA regulated synaptic structural and functional impairment in the ACC and its relationship to attention deficit disorder in Pb exposed mice. Results showed that Pb exposure induced presynaptic impairment and structural alterations in the ACC. Furthermore, we screened for critical miRNA targets responsible for the synaptic alteration. We found that miR-130, which regulates presynaptic vesicle releasing protein SNAP-25, was responsible for the presynaptic impairment in the ACC and attention deficits in mice. Blocking miR-130 function reversed the Pb-induced decrease in the expression of its presynaptic target SNAP-25, leading to the redistribution of presynaptic vesicles, as well as improved presynaptic function and attention in Pb exposed mice. We report, for the first time, that miR-130 regulating SNAP-25 mediates Pb-induced presynaptic structural and functional impairment in the ACC along with attention deficit disorder in mice.

Plant invasions facilitated by suppression of root nutrient acquisition rather than by disruption of mycorrhizal association in the native plant.

Invasive species have profound negative impacts on native ranges. Unraveling the mechanisms employed by invasive plant species is crucial to controlling invasions. One important approach that invasive plants use to outcompete native plants is to disrupt mutualistic interactions between native roots and mycorrhizal fungi. However, it remains unclear how differences in the competitive ability of invasive plants affect native plant associations with mycorrhizae. Here, we examined how a native plant, Xanthium strumarium, responds to invasive plants that differed in competitive abilities (i.e., as represented by aboveground plant biomass) by measuring changes in root nitrogen concentration (root nutrient acquisition) and mycorrhizal colonization rate. We found that both root nitrogen concentration and mycorrhizal colonization rate in the native plant were reduced by invasive plants. The change in mycorrhizal colonization rate of the native plant was negatively correlated with both aboveground plant biomass of the invasive plants and the change in aboveground plant biomass of the native plant in monocultures relative to mixed plantings. In contrast, the change in root nitrogen concentration of the native plant was positively correlated with aboveground plant biomass of the invasive plants and the change in aboveground plant biomass of the native plant. When we compared the changes in mycorrhizal colonization rate and root nitrogen concentration in the native plant grown in monocultures with those of native plants grown with invasive plants, we observed a significant tradeoff. Our study shows that invasive plants can suppress native plants by reducing root nutrient acquisition rather than by disrupting symbiotic mycorrhizal associations, a novel finding likely attributable to a low dependence of the native plant on mycorrhizal fungi.

Inherent conflicts between reaction norm slope and plasticity indices when comparing plasticity: a conceptual framework and empirical test.

Phenotypic plasticity index (PI), the slope of reaction norm (K) and relative distances plasticity index (RDPI), the most commonly used estimators, have occasionally been found to generate different plasticity rankings between groups (species, populations, cultivars or genotypes). However, no effort has been made to determine how frequent this incongruence is, and the factors that influence the occurrence of the incongruence. To address these problems, we first proposed a conceptual framework and then tested the framework (its predictions) by reanalyzing 1248 sets of published data. Our framework reveals inherent conflicts between K and PI or RDPI when comparing plasticity between two groups, and the frequency of these conflicts increases with increasing inter-group initial trait difference and/or K values of the groups compared. More importantly, the estimators also affect the magnitude of the inter-group plasticity differences even when they do not change groups' plasticity rankings. The above-mentioned effects of plasticity estimators were confirmed by our empirical test using data from the literature, and the conflicts occur in 203 (16%) of the 1248 comparisons between K and indices, indicating that a considerable proportion of the comparative conclusions on plasticity in literature are estimator-dependent. The frequency of the conflicts is influenced by phylogenetic relatedness of the groups compared, being lower when comparing within relative to between species, but not by specific types of environments, traits and species. Our study indicates that care is needed to select estimator when comparing groups' plasticity, and that the conclusions in relevant literature should be treated with great caution.

Phenotypic plasticity and exotic plant invasions: Effects of soil nutrients, species nutrient requirements, and types of traits.

High-phenotypic plasticity has long been considered as a characteristic promoting exotic plant invasions. However, the results of the studies testing this hypothesis are still inconsistent. Overlooking the effects of species resource requirements and environmental resource availability may be the main reasons for the ambiguous conclusions. Here, we compared phenotypic plasticity between five noxious invasive species with different nutrient requirements (evaluated using the soil nutrient status of their natural distribution ranges) and their phylogenetically related natives under five nutrient levels. We found that species with high-nutrient requirements showed greater plasticity of total biomass than species with low-nutrient requirements, regardless of their status (invasive or native). Invasives with high-nutrient requirements had greater growth plasticity than their related natives, which may contribute to their invasiveness under high-nutrient environments. However, compared with the related natives, a higher growth plasticity may not help exotic species with low-nutrient requirements to invade nutrient-rich habitats, and exotic species with high-nutrient requirements to invade nutrient-limited habitats. In contrast, invasives with low-nutrient requirements exhibited lower growth plasticity than their related natives, contributing to their invasiveness under nutrient-limited habitats. Functional traits showed growth-related plasticity in only 10 cases (3.8%), and there was no functional trait whose plastic response to soil nutrients was beneficial to exotic plant invasions. Our study indicates that low-growth plasticity could also promote exotic plant invasions, high plasticity may not necessarily lead to invasiveness. We must test the adaptive significance of plasticity of functional traits when studying its biological roles.

Riverside underwater noise pollution threaten porpoises and fish along the middle and lower reaches of the Yangtze River, China.

The Yangtze River exhibits a high biodiversity and plays an important role in global biodiversity conservation. As the world's busiest inland river in regard to shipping, little attention has been paid to underwater noise pollution. In 2017, the underwater noise level in 25 riverside locations along the middle and lower reaches of the Yangtze River mainly at night time were investigated by using passive acoustic monitoring method. Approximately 88% and 40% of the sampled sites exhibit noise levels exceeding the underwater acoustic thresholds of causing responsiveness and temporary threshold shift, respectively, in cetacean. Noise pollution may impose a high impact on fish with physostomous swim bladders and Weberian ossicles, such as silver carp, bighead carp, goldfish and common carp, whereas it may affect fish with physoclistous swim bladders and without Weberian ossicles, such as lake sturgeon and paddlefish, to a lesser extent. Noise levels reductions of approximately 10 and 20 dB were observed in the middle and lower reaches, respectively, of the Yangtze River over the 2012 level. The green development mode of the ongoing construction of green shipping in the Yangtze River Economic Belt, including the development of green shipping lanes, ports, ships and transportation organizations, may account for the alleviated underwater noise pollution. Follow-up noise mitigation endeavors, such as the extension of ship speed restrictions and the study and implementation of the optimal navigation speed in ecologically important areas, are required to further reduce the noise level in the Yangtze River to protect local porpoises and fish.

The influence of hypoglycemia on the specific quality of life in type 2 diabetes mellitus: a comparative cross-sectional study of diabetics with and without hypoglycemia in Xi'an, China.

PURPOSE: This study aims to explore the incidence of hypoglycemia in patients with type 2 diabetes mellitus (T2DM) and the influence of hypoglycemia on the specific quality of life in T2DM patients. METHODS: It was a comparative cross-sectional study consisting of 519 T2DM patients in Xi'an, China and patients were investigated by self-reported hypoglycemia and specific quality of life questionnaires from September 2019 to January 2020. Descriptive analysis, t-test, Chi-square test, hierarchical regression analysis and stepwise multiple regression analysis were applied to assess the influence of hypoglycemia on the specific quality of life. RESULTS: The incidence of hypoglycemia in T2DM patients was 32.18%. The mean score of specific quality of life in diabetes without hypoglycemia was 57.33 ± 15.36 and was 61.56 ± 17.50 in those with hypoglycemia, which indicated that hypoglycemia had a serious impact on the quality of life of diabetics (t = - 5.172, p = 0.000). In the Univariate analysis of specific quality of life, age, education background, marital status, living status, duration of diabetes, monthly income per capita were independent and significant factors associated with specific quality of life of two groups of T2DM patients (p < 0.05). In the hierarchical regression analysis, the duration of the diabetes more than 11 years and the frequency of hypoglycemia more than 6 times in half a year entered the equation of specific quality of life of 519 diabetics respectively (p < 0.001). In multiple linear regression analysis, age, marital status and income all entered the regression equation of quality of life of the two groups (p < 0.05). CONCLUSION: Hypoglycemia will have a serious impact on the quality of life of T2DM patients. In order to improve the living quality in diabetics, effective measurements should be taken to strengthen the management of blood glucose and to avoid hypoglycemia.

Effects of the invasive plant Xanthium strumarium on diversity of native plant species: A competitive analysis approach in North and Northeast China.

Xanthium strumarium is native to North America and now has become one of the invasive alien species (IAS) in China. In order to detect the effects of the invader on biodiversity and evaluate its suitable habitats and ecological distribution, we investigated the abundance, relative abundance, diversity indices, and the number of the invasive and native plants in paired invaded and non-invaded quadrats in four locations in North and Northeast China. We also analyzed the effects of monthly mean maximum and minimum temperatures, relative humidity (%), and precipitations (mm). Strong positive significant (P < 0.01) correlation and maximum interspecific competition (41%) were found in Huailai between invaded and non-invaded quadrats. Shannon's Diversity Index showed that non-invaded plots had significantly (P < 0.05) more diversified species than invaded ones. The significant (P < 0.05) Margalef's Richness Index was found in Huailai and Zhangjiakou in non-invaded recorded heterogeneous nature of plant communities. Similarly, significant (P < 0.05) species richness found in Huailai and Zhangjiakou in non-invaded quadrats compared to invaded ones. Maximum evenness of Setaria feberi (0.47, 0.37), Seteria viridis (0.43) found in Fushun and Zhangjiakou recorded more stable in a community compared to other localities. Evenness showed positive relationship of Shannon Entropy within different plant species. The higher dissimilarity in plant communities found in Huailai (87.06%) followed by Yangyuan (44.43%), Zhangjiakou (40.13%) and Fushun (29.02%). The significant (P < 0.01) value of global statistics R (0.943/94.3%) showed high species diversity recorded in Huailai followed by Zhangjiakou recorded by non-metric multidimensional scaling and analysis of similarity between invaded and non-invaded plots. At the end it was concluded that the diversity indices reduced significantly (P < 0.05) in invaded quadrats indicated that native plant species become less diverse due to X. strumarium invasion. The degrees of X. strumarium invasion affected on species richness resulted to reduce diversity indices significantly in invaded quadrats.

MicroRNA-7 targets T-Box 2 to inhibit epithelial-mesenchymal transition and invasiveness in glioblastoma multiforme.

The dysregulation of microRNA expression in cancer has been associated with the epithelial-mesenchymal transition (EMT) that triggers invasive ability and increases therapeutic resistance. Here, we determined the microRNA expression profile of seven tumor tissues from patients with glioblastoma multiforme (GBM) by use of microRNA array analysis. We discovered that microRNA-7 (miR-7) is consistently downregulated in all tumor samples. Using the microRNA.org algorithm, the T-box 2 gene (TBX2) was identified as a candidate gene targeted by miR-7. In contrast to miR-7, TBX2 had an increased expression in GBM tumors and was linked to poor prognosis. We confirmed that TBX2 mRNA and protein production are significantly repressed by overexpressing miR-7 in GBM cells in vitro. The reporter assay showed that miR-7 significantly represses the signal from luciferase with the 3' UTR of TBX2. Furthermore, TBX2 overexpression decreased E-cadherin expression and increased Vimentin expression, causing an increasing number of invaded cells in the invasion assay, as well as pulmonary metastasis in vivo. Our findings demonstrated that overexpression of TBX2 in GBM tumors via the downregulation of miR-7 leads to EMT induction and increased cell invasion.

Lesser leaf herbivore damage and structural defense and greater nutrient concentrations for invasive alien plants: Evidence from 47 pairs of invasive and non-invasive plants.

Empirical evidence of enemy release is still inconsistent for invasive alien plant species, although enemy release is the key assumption for both the enemy release hypothesis (ERH) and the evolution of increased competitive ability hypothesis (EICA). In addition, little effort has been made to test this assumption in terms of defense investment using a multi-species comparative approach. Using a phylogenetically controlled within-study meta-analytical approach, we compared leaf herbivore damage, structural defenses and nutrients between 47 pairs of invasive versus native and/or non-invasive alien plants in China. The invasive relative to the co-occurring native or non-invasive (native and non-invasive alien) plants incurred lesser leaf herbivore damage, had lesser leaf concentrations of cellulose, hemicellulose, lignin and carbon, lesser leaf density and carbon or lignin to nitrogen ratio but greater nutrients, which may facilitate success of the invasive plants. The lesser structural investment did not result in lesser leaf construction costs for the invaders, which may be associated with their greater leaf nitrogen concentration. However, the invasive plants were not significantly different from the non-invasive alien plants in any trait. Our results provide strong evidence for ERH, also are consistent with EICA, and indicate that enemy release may be an important factor in alien plant invasions.

Uterine Microbiota of Dairy Cows With Clinical and Subclinical Endometritis.

The objective of this study was to characterize the uterine microbiota of dairy cows with clinical and subclinical endometritis and to identify the potential bacterial genera as well as their interactions associated with uterine disease. Uterine flush samples (n = 27) were collected from 13 healthy, 5 subclinical endometritic (SE), and 9 clinical endometritic (CE) cows at 30 days postpartum. Microbial DNA from uterine flush samples was subjected to sequencing of the 16S rRNA gene on the Illumina MiSeq platform. The uterine microbiota of healthy, SE, and CE cows had similarly complex microbial diversity, and shared 293 of 445 operational taxonomic units. However, endometritic and healthy cows could be discriminated by the relative abundance of bacterial genera. In CE cows, the uterine microbiota was characterized by increased abundance of Fusobacterium and unique presence of Trueperella and Peptoniphilus. For SE cows, known intrauterine pathogens were almost absent and the uterine microbiota was characterized by enrichment of Lactobacillus and Acinetobacter. Analysis of correlations between bacterial genera showed that the uterine microbiota exhibited two co-occurrence groups (i.e., the Lactococcus and the Fusobacterium COGs), indicating that the synergistic effect by co-occurred bacteria may be an important aspect of pathogenesis. Our findings support that common uterine pathogens are not associated with subclinical endometritis at 30 days postpartum and indicate the need of investigating the role of commensal bacteria such as Lactobacillus, and Acinetobacter in the inflammatory process of uterine endometrium.

Predictors of Response to Autologous Dendritic Cell Therapy in Glioblastoma Multiforme.

Background: Glioblastoma (GBM) is the most common and lethal primary malignant glioma in adults. Dendritic cell (DC) vaccines have demonstrated promising results in GBM clinical trials. However, some patients do not respond well to DC therapy, with survival rates similar to those of conventional therapy. We retrospectively analyzed clinical and laboratory data to evaluate the factors affecting vaccine treatment. Methods: Forty-seven patients with de novo GBM were enrolled at China Medical University Hospital between 2005 and 2010 and divided into two subgroups. One subgroup of 27 patients received postsurgical adjuvant immunotherapy with autologous dendritic cell/tumor antigen vaccine (ADCTA) in conjunction with conventional treatment of concomitant chemoradiotherapy (CCRT) with temozolomide. The other 20 patients received only postsurgical conventional treatment without immunotherapy. Immunohistochemistry for CD45, CD4, CD8, programed death ligand 1 (PD-L1), and programed death 1 (PD-1) was performed on sections of surgical tumor specimens and peripheral blood mononuclear cells (PBMCs). Pearson's correlation, Cox proportional hazard model, and Kaplan-Meier analyses were performed to examine the correlations between the prognostic factors and survival rates. Results: Younger age (<57 years), gross total resection, and CCRT and PD-1+ lymphocyte counts were significant prognostic factors of overall survival (OS) and progression-free survival (PFS) in the ADCTA group. Sex, CD45+ lymphocyte count, CD4+ or CD8+ lymphocyte count, tumor PD-L1 expression, isocitrate dehydrogenase 1 mutation, and O6 methylguanine-DNA methyltransferase promoter methylation status were not significant factors in both groups. In the ADCTA group, patients with tumor-infiltrating lymphocytes (TILs) with a lower PD-1+/CD8+ ratio (≤0.21) had longer OS and PFS (median OS 60.97 months, P < 0.001 and PFS 11.2 months, P < 0.008) compared to those with higher PD-1+/CD8+ ratio (>0.21) (median OS 20.07 months, P < 0.001 and PFS 4.43 months, P < 0.008). Similar results were observed in patients' PBMCs; lymphocyte counts with lower PD-1+/CD8+ ratio (≤0.197) had longer OS and PFS. There was a significant correlation of PD-1+/CD8+ ratio between TILs and PBMCs (Pearson's correlation R2 = 0.6002, P < 0.001). By contrast, CD4-, CD8-, but PD-1+, CD45+ tumor-infiltrating lymphocytes have no impact on OS and PFS (P = 0.073 and P = 0.249, respectively). Conclusion: For patients receiving DC vaccine adjuvant therapy, better outcomes are predicted in patients with younger age, with TILs or PBMCs with lower PD-1+/CD8+ ratio, with gross tumor resection, and receiving CCRT.

Higher photosynthesis, nutrient- and energy-use efficiencies contribute to invasiveness of exotic plants in a nutrient poor habitat in northeast China.

The roles of photosynthesis-related traits in invasiveness of introduced plant species are still not well elucidated, especially in nutrient-poor habitats. In addition, little effort has been made to determine the physiological causes and consequences of the difference in these traits between invasive and native plants. To address these problems, we compared the differences in 16 leaf functional traits related to light-saturated photosynthetic rate (Pmax ) between 22 invasive and native plants in a nutrient-poor habitat in northeast China. The invasive plants had significantly higher Pmax , photosynthetic nitrogen- (PNUE), phosphorus- (PPUE), potassium- (PKUE) and energy-use efficiencies (PEUE) than the co-occurring natives, while leaf nutrient concentrations, construction cost (CC) and specific leaf area were not significantly different between the invasive and native plants. The higher PNUE contributed to higher Pmax for the invasive plants, which in turn contributed to higher PPUE, PKUE and PEUE. CC changed independently with other traits such as Pmax , PNUE, PPUE, PKUE and PEUE, showing two trait dimensions, which may facilitate acclimation to multifarious niche dimensions. Our results indicate that the invasive plants have a superior resource-use strategy, i.e. higher photosynthesis under similar resource investments, contributing to invasion success in the barren habitat.

Lactobacillus rhamnosus GR-1 Ameliorates Escherichia coli-Induced Inflammation and Cell Damage via Attenuation of ASC-Independent NLRP3 Inflammasome Activation.

Escherichia coli is a major environmental pathogen causing bovine mastitis, which leads to mammary tissue damage and cell death. We explored the effects of the probiotic Lactobacillus rhamnosus GR-1 on ameliorating E. coli-induced inflammation and cell damage in primary bovine mammary epithelial cells (BMECs). Increased Toll-like receptor 4 (TLR4), NOD1, and NOD2 mRNA expression was observed following E. coli challenge, but this increase was attenuated by L. rhamnosus GR-1 pretreatment. Immunofluorescence and Western blot analyses revealed that L. rhamnosus GR-1 pretreatment decreased the E. coli-induced increases in the expression of the NOD-like receptor family member pyrin domain-containing protein 3 (NLRP3) and the serine protease caspase 1. However, expression of the adaptor protein apoptosis-associated speck-like protein (ASC, encoded by the Pycard gene) was decreased during E. coli infection, even with L. rhamnosus GR-1 pretreatment. Pretreatment with L. rhamnosus GR-1 counteracted the E. coli-induced increases in interleukin-1ß (IL-1ß), -6, -8, and -18 and tumor necrosis factor alpha mRNA expression but upregulated IL-10 mRNA expression. Our data indicate that L. rhamnosus GR-1 reduces the adhesion of E. coli to BMECs, subsequently ameliorating E. coli-induced disruption of cellular morphology and ultrastructure and limiting detrimental inflammatory responses, partly via promoting TLR2 and NOD1 synergism and attenuating ASC-independent NLRP3 inflammasome activation. Although the residual pathogenic activity of L. rhamnosus, the dosage regimen, and the means of probiotic supplementation in cattle remain undefined, our data enhance our understanding of the mechanism of action of this candidate probiotic, allowing for development of specific probiotic-based therapies and strategies for preventing pathogenic infection of the bovine mammary gland.

Lead Exposure Impairs Hippocampus Related Learning and Memory by Altering Synaptic Plasticity and Morphology During Juvenile Period.

Lead (Pb) is an environmental neurotoxic metal. Pb exposure may cause neurobehavioral changes, such as learning and memory impairment, and adolescence violence among children. Previous animal models have largely focused on the effects of Pb exposure during early development (from gestation to lactation period) on neurobehavior. In this study, we exposed Sprague-Dawley rats during the juvenile stage (from juvenile period to adult period). We investigated the synaptic function and structural changes and the relationship of these changes to neurobehavioral deficits in adult rats. Our results showed that juvenile Pb exposure caused fear-conditioned memory impairment and anxiety-like behavior, but locomotion and pain behavior were indistinguishable from the controls. Electrophysiological studies showed that long-term potentiation induction was affected in Pb-exposed rats, and this was probably due to excitatory synaptic transmission impairment in Pb-exposed rats. We found that NMDA and AMPA receptor-mediated current was inhibited, whereas the GABA synaptic transmission was normal in Pb-exposed rats. NR2A and phosphorylated GluR1 expression decreased. Moreover, morphological studies showed that density of dendritic spines declined by about 20 % in the Pb-treated group. The spine showed an immature form in Pb-exposed rats, as indicated by spine size measurements. However, the length and arborization of dendrites were unchanged. Our results suggested that juvenile Pb exposure in rats is associated with alterations in the glutamate receptor, which caused synaptic functional and morphological changes in hippocampal CA1 pyramidal neurons, thereby leading to behavioral changes.

Genetic characterization of bovine viral diarrhea virus strains in Beijing, China and innate immune responses of peripheral blood mononuclear cells in persistently infected dairy cattle.

To acquire epidemiological data on the bovine viral diarrhea virus (BVDV) and identify cattle persistently infected (PI) with this virus, 4,327 samples from Holstein dairy cows were screened over a four-year period in Beijing, China. Eighteen BVD viruses were isolated, 12 from PI cattle. Based on genetic analysis of their 5'-untranslated region (5'-UTR), the 18 isolates were assigned to subgenotype BVDV-1m, 1a, 1d, 1q, and 1b. To investigate the innate immune responses in the peripheral-blood mononuclear cells of PI cattle, the expression of Toll-like receptors (TLRs), RIG-I-like receptors, interferon-α (IFN-α), IFN-ß, myxovirus (influenza virus) resistance 1 (MX1), and interferon stimulatory gene 15 (ISG15) was assessed by qPCR. When compared with healthy cattle, the expression of TLR-7, IFN-α, and IFN-ß mRNA was downregulated, but the expression of MX1 and ISG-15 mRNA was upregulated in PI cattle. Immunoblotting analysis revealed that the expression of interferon regulatory factor 3 (IRF-3) and IRF-7 was lower in PI cattle than in healthy cattle. Thus, BVDV-1m and 1a are the predominant subgenotypes in the Beijing region, and the strains are highly divergent. Our findings also suggest that the TLR-7/IRF-7 signaling pathway plays a role in evasion of host restriction by BVDV.

Extramedullary hematopoiesis (EMH) in laboratory animals: offering an insight into stem cell research.

Extramedullary hematopoiesis (EMH) is a pathological process secondary to underlying bone marrow (BM) insufficiency in adults. It is characterized by the emergence of multipotent hematopoietic progenitors scattered around the affected tissue, most likely in the spleen, liver, and lymph node, etc. EMH in patients frequently receives less medical attention and is neglected unless a compressive or obstructive hematopoietic mass appears to endanger the patient's life. However, on a biological basis, EMH reflects the alteration of relationships among hematopoietic stem and progenitor cells (HSPCs) and their original and new microenvironments. The ability of hematopoietic stem cells (HSCs) to mobilize from the bone marrow and to accommodate and function in extramedullary tissues is rather complicated and far from our current understanding. Fortunately, many reports from the studies of drugs and genetics using animals have incidentally found EMH to be involved. Thereby, the molecular basis of EMH could further be elucidated from those animals after cross-comparison. A deeper understanding of the extramedullary hematopoietic niche could help expand stem cells in vitro and establish a better treatment in patients for stem cell transplantation.

Correlation between serum IGF-1 and blood lead level in short stature children and adolescent with growth hormone deficiency.

UNLABELLED: This study aimed to investigate correlation between serum insulin-like growth factor-1 (IGF-1) and blood lead level in short stature children with growth hormone deficiency (GHD), and IGF-1 signal molecules were investigated in lead exposed rats. Our findings may provide evidence for clarifying pathogenesis of lead induced short stature in children. METHODS: 880 short stature children were recruited from clinics and divided into GHD group and idiopathic short stature (ISS) group according to the GH peak in growth hormone stimulation test. The height, body weight, serum IGF-1 level and blood lead level were determined. A rat model of lead poisoning was used to establish and western blot assay was employed to detect the phosphorylation of signaling molecules (MAPK and PI3K/Akt) related to IGF-1 signaling pathway. RESULTS: In GHD group, the height, body weight and serum IGF-1 level were significantly lower, but the blood lead level was significantly higher than those in ISS group (P<0.05). Western blot assay confirmed that the protein expression of phosphorylated ERK1/2, JNK, p38, Akt473 and Akt308 increased significantly (P<0.01) in lead exposure rats. CONCLUSION: Our study suggesting that reduction in IGF-1 in children with GHD is associated with blood lead level. Lead exposure may induce expression of phosphorylated MAPK and Akt signaling molecules. The activation of these molecules may influence binding of IGF-1 and tyrosine kinase receptor IGFIR to regulate cell growth via the MAPK and Akt signaling pathways, which then interfere with growth-promoting effect of IGF-1 in short children.

Therapeutic potential of microRNA let-7: tumor suppression or impeding normal stemness.

The first microRNA, let-7, and its family were discovered in Caenorhabditis elegans and are functionally conserved from worms to humans in the regulation of embryonic development and stemness. The let-7 family has been shown to have an essential role in stem cell differentiation and tumor-suppressive activity. Deregulating expression of let-7 is commonly reported in many human cancers. Emerging evidence has accumulated and suggests that reestablishment of let-7 in tumor cells is a valuable therapeutic strategy. However, findings reach beyond tumor therapeutics and may impinge on stemness and differentiation of stem cells. In this review, we discuss the role of let-7 in development and differentiation of normal adult stem/progenitor cells and offer a viewpoint of the association between deregulated let-7 expression and tumorigenesis. The regulation of let-7 expression, cancer-relevant let-7 targets, and the application of let-7 are highlighted.

[Extraction of bridge over water from high-resolution remote sensing images based on spectral characteristics of ground objects].

Bridge over water is a typical man-made target. Using the high-resolution optical remote sensing images, to extract bridge over water appears significant for civilian, military, and commerce. First, in the present paper, according to the spectral characteristics of water in near-infrared spectrum, water information is extracted using the iterative method for the threshold value, to limit the spatial extent of bridge extraction. Second, mathematical morphology is performed on the water information, to connect the separated water bodies due to the presence of bridges on the image. Third, overlay analysis is conducted between the two images before and after mathematical morphology operations, to extract the potential bridge. Finally, based on priori-knowledge of the bridge, the false bridge is removed. In this paper an experimental area is selected to verify the effectiveness and applicability of the method. Experimental results show that the method is effective for bridge extraction over water by using high-resolution remote sensing images based on spectral characteristics of ground objects.