Bacillus thuringiensis C25 which is rich in cell wall degrading enzymes efficiently controls lettuce drop caused by Sclerotinia minor

European Journal of Plant Pathology - Sclerotinia is a phytopathogenic genus of fungi that form sclerotia: black, hard, seed-like functioning bodies. Sclerotinia sclerotiorum and Sclerotinia minor...     

Gene therapy using non-viral peptide vector in a canine systemic lupus erythematosus model

Although viral vectors are commonly used for therapeutic gene delivery, their applications are limited due to their specific cell membrane receptor-mediated infection and host immune response. In the present study, we constructed a non-viral peptide vector and applied it in the treatment of experimentally induced systemic lupus erythematosus-like disease in dogs. For therapeutic gene construction, the extracellular domain of canine CTLA-4, and the CH2-CH3 domains of canine immunoglobulin alpha constant region were inserted between the cytomegalovirus promoter and poly-adenylation sequence of bovine growth hormone. The constructed therapeutic gene was ligated to the non-viral synthetic peptide vector and was applied to systemic lupus erythematosus-like disease induced dogs. After gene therapy, clinical signs of systemic lupus erythematosus were reduced dramatically: the anti-nuclear antibody titers and urine protein/creatinine ratios were recovered to normal values, and the skin regained its normal histological features. The peptide vector did not show either tissue specific tropism or host induced immune response.     

Root storage of nitrogen applied in autumn and its remobilization to new growth in spring of persimmon trees (Diospyros kaki cv. Fuyu)

This study was conducted to understand the effect of N supply in autumn on its uptake and distribution in tree parts and the utilization of reserve N the following year in persimmon trees (Diospyros kaki cv. Fuyu). The treated trees received 22.5-g N each for two successive years as a 3.5% urea solution from September 18 at 5-day intervals. Trees absorbed about 30% on average of the N applied in autumn. Sixty four to 83% of the N absorbed in autumn was in perennial parts, and 65–72% of that was in roots. Total N in perennial parts of the tree fertilized with N increased by over 4.28 g while leaf N changed little during senescence, indicating that the reserve N was constituted mostly by the N absorbed in autumn. Total N in the new growth was about the same as the amount of N declined in spring from perennial parts, indicating that there was little contribution by soil N to sustain new growth. Total dry weights of new growth the following year in a with-N tree were greater by over 34 g than those in a without-N tree.     

In vitro effects of Actinobacillus pleuropneumoniae on inducible nitric oxide synthase and cyclooxygenase-2 in porcine alveolar macrophages

OBJECTIVE: To determine the amount of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) activity in alveolar macrophages in response to Actinobacillus pleuropneumoniae (APP) by determining nitric oxide (NO) and prostaglandin E2 (PGE2) concentrations. SAMPLE POPULATION: Freshly isolated porcine alveolar macrophages. PROCEDURE: Alveolar macrophages were incubated for 48 hours with APP (1 X 10(4) colony-forming units/mL), interleukin-1beta, (IL-1beta; 5 U/mL), tumor necrosis factor-alpha (TNFalpha; 500 U/mL), interferon-gamma (IFN-gamma, 100 U/mL), or lipopolysaccharide (LPS; 10 microg/mL). In a second experiment, alveolar macrophages were incubated with fresh medium (negative control), APP alone, or APP with 1 of the following: IL-1beta, TNF-alpha, or IFN-gamma. In a third experiment, alveolar macrophages were incubated with fresh medium (negative control), LPS (positive control), APP alone, or APP with 1 of the following: an iNOS inhibitor (3.3 microM), a COX-2 inhibitor (10 microM); or both the iNOS and COX-2 inhibitors. Supernatant was obtained at 0, 3, 6, 9, 12, 24, and 48 hours after treatment for determination of NO and PGE2 production. RESULTS: The addition of APP to alveolar macrophages resulted in significant increases in NO and PGE2 production. The addition of APP and IFN-gamma synergistically induced NO production. Inhibition of iNOS and COX-2 decreased NO and PGE2 production, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: In vitro activation of alveolar macrophages by APP results in increased production of NO and PGE2. Nitric oxide and PGE2 production appears to be largely dependent on iNOS and COX-2 activity. Pharmacologic modulation of iNOS and COX-2 activity may represent a therapeutic target for pigs with pleuropneumonia.     

Infection rate of Ehrlichia risticii, the agent of Potomac horse fever, in freshwater stream snails (Juga yrekaensis) from northern California

Juga yrekaensis freshwater snails were tested for trematode stages and for Ehrlichia risticii DNA using a nested PCR assay. Snails were collected monthly from two Potomac horse fever (PHF) endemic locations in northern California (Montague and Weed).The trematode infection rate varied between 40 and 93.3% in large snails (shell size >15mm) and between 0 and 13.3% in small snails (<15mm). The highest trematode infection rate for large and small snails was recorded in September and the lowest infection rate for large snails was recorded in June (Weed) and October (Montague). The E. risticii PCR infection rate among small snails from both sites was similar and varied monthly between 0 and 3.3%. The PCR infection rate for large snails from Weed was high in May (20.0%) and decreased progressively until November (10.0%). The PCR infection rate for large snails from Montague was 5.0% in May, 26.3% in August and 16. 7% in October. PCR-positive snails were always related to the microscopic detection of trematode stages (virgulate cercariae).This study provides evidence that J. yrekaensis are infected with trematode cercariae that harbor E. risticii. The number of snails harboring trematode stages and the number of PCR positive snails varied with the size of the snails, the month of collection, and the geographic origin.     

Investigation of pseudorabies virus latency in nervous tissues of seropositive pigs exposed to field strain

The prevalence and quantity of latent pseudorabies virus (PrV) in nervous tissues of pigs exposed to field strain in Korea was investigated by nested and real-time PCR. Nervous tissues including trigeminal ganglion (TG), olfactory bulb (OB), and brain stem (BS) were collected from 94 seropositive pigs. PrV latent infection in nervous tissues was initially investigated by nested PCR targeting three glycoprotein genes (gB, gE, and gG). Based on the obtained result, latent infection was detected in 95.7% of screened animals. Furthermore, it was revealed that the examined tissues harbored different copy numbers of latent PrV genome ranging from <10(2.0) to 10(7.1) copies per microgram of genomic DNA in real-time PCR analysis. These results show that under normal conditions, levels of latent PrV in the nervous tissues of pigs can vary across a wide range. Therefore, the data presented here provides information regarding control of the endemic state of PrV in Korea.     

The effects of transplacental porcine circovirus type 2 infection on porcine epidemic diarrhoea virus-induced enteritis in preweaning piglets

The effects of transplacental porcine circovirus type 2 (PCV2) infection on porcine epidemic diarrhoea virus (PEDV)-induced enteritis were examined in neonatal piglets. Six pregnant sows were randomly allocated to an infected (n=3) or control group (n=3). Three pregnant sows were inoculated intranasally with 6 mL of tissue culture fluid containing 1.2 x 10(5) tissue culture infective doses 50% (TCID(50))/mL of PCV2 strain SNUVR000470 three weeks before the expected farrowing date. Three control pregnant sows were similarly exposed to uninfected cell culture supernatants. Thirty piglets from PCV2-infected sows were randomly assigned to two groups (A and B) of 15 piglets each. Another 30 piglets from noninfected sows were randomly assigned to two groups (C and D) of 15 piglets each. The piglets in groups A and C were dosed orally at three days of age with 2mL of virus stock (1 x 10(6.5) TCID(50)/mL) of the PEDV strain, SNUVR971496, at the third passage. The mean villous height and crypt depth (VH:CD) ratio in PEDV-infected piglets from PCV2-infected sows (group A) were significantly different from those of the PEDV-infected piglets from PCV2 negative sows (group C) at 36, 48, and 72 h post-inoculation (hpi) (P<0.05). In PEDV-infected piglets from PCV2-infected sows (group A), significantly more PEDV nucleic acid was detected in the jejunal tissues (P<0.05) at 24 hpi than in the same tissues of the PEDV-infected piglets from PCV2 negative sows (group C). Thereafter, at 36, 48, 60, and 70 hpi significantly more PEDV nucleic acid (P<0.05) was detected in the jejunal tissues of the PEDV-infected piglets from PCV2 negative sows (group C) than those of the PEDV-infected piglets from the PCV2-infected sows (group A). It is concluded that the clinical course of PEDV disease was markedly affected by transplacental infection of PCV2.     

Feline adipose tissue-derived mesenchymal stem cells pretreated with IFN-γ enhance immunomodulatory effects through the PGE2 pathway

BackgroundPreconditioning with inflammatory stimuli is used to improve the secretion of anti-inflammatory agents in stem cells from variant species such as mouse, human, and dog. However, there are only few studies on feline stem cells.ObjectivesThis study aimed to evaluate the immune regulatory capacity of feline adipose tissue-derived (fAT) mesenchymal stem cells (MSCs) pretreated with interferon-gamma (IFN-γ).MethodsTo assess the interaction of lymphocytes and macrophages with IFN-γ-pretreated fAT-MSCs, mouse splenocytes and RAW 264.7 cells were cultured with the conditioned media from IFN-γ-pretreated MSCs.ResultsPretreatment with IFN-γ increased the gene expression levels of cyclooxygenase-2, indoleamine 2,3-dioxygenase, hepatocyte growth factor, and transforming growth factor-beta 1 in the MSCs. The conditioned media from IFN-γ-pretreated MSCs increased the expression levels of M2 macrophage markers and regulatory T-cell markers compared to those in the conditioned media from naive MSCs. Further, prostaglandin E₂ (PGE₂) inhibitor NS-398 attenuated the immunoregulatory potential of MSCs, suggesting that the increased PGE₂ levels induced by IFN-γ stimulation is a crucial factor in the immune regulatory capacity of MSCs pretreated with IFN-γ.ConclusionsIFN-γ pretreatment improves the immune regulatory profile of fAT-MSCs mainly via the secretion of PGE₂, which induces macrophage polarization and increases regulatory T-cell numbers.