Q fever in pregnant goats: humoral and cellular immune responses

Q fever is a zoonosis caused by the intracellular bacterium Coxiella burnetii. Both humoral and cellular immunity are important in the host defence against intracellular bacteria. Little is known about the immune response to C. burnetii infections in domestic ruminants even though these species are the major source of Q fever in humans. To investigate the goat’s immune response we inoculated groups of pregnant goats via inhalation with a Dutch outbreak isolate of C. burnetii. All animals were successfully infected. Phase 1 and Phase 2 IgM- and IgG-specific antibodies were measured. Cellular immune responses were investigated by interferon-gamma, enzyme-linked immunosorbent spot test (IFN-γ Elispot), lymphocyte proliferation test (LPT) and systemic cytokines. After two weeks post inoculation (wpi), a strong anti-C. burnetii Phase 2 IgM and IgG antibody response was observed while the increase in IgM anti-Phase 1 antibodies was less pronounced. IgG anti-Phase 1 antibodies started to rise at 6 wpi. Cellular immune responses were observed after parturition. Our results demonstrated humoral and cellular immune responses to C. burnetii infection in pregnant goats. Cell-mediated immune responses did not differ enough to distinguish between Coxiella-infected and non-infected pregnant animals, whereas a strong-phase specific antibody response is detected after 2 wpi. This humoral immune response may be useful in the early detection of C. burnetii-infected pregnant goats.     

Effect of soybean lipoxygenase on volatile generation and inhibition of Aspergillus flavus mycelial growth

Volatiles generated from lipoxygenase (LOX) normal and LOX deficient soybean (Glycine max) varieties with and without added lipase inhibited Aspergillus flavus mycelial growth and aflatoxin production. Soybean volatiles were analyzed using a solid phase microextraction (SPME) method combined with gas chromatography-mass spectrometry (GC-MS). Twenty-one compounds, including 11 aldehydes, three alcohols, four ketones, one furan, one alkane, and one alkene were detected in the LOX normal soybean line. However, only nine volatile compounds were observed in the LOX deficient soybean variety. The antifungal aldehydes hexanal and (E)-2-hexenal were observed in both LOX normal and LOX deficient lines and were detected at significantly higher amounts in soybean homogenate with added lipase. These aldehydes may be formed through alternate pathways, other than the LOX pathway, and may account for the inhibition of A. flavus growth observed. Other volatiles detected, particularly the ketones and alcohols, may contribute to the antifungal activity observed in both LOX normal and LOX deficient soybean lines. These results suggest that other factors, other than LOX activity, may better explain why soybeans are generally not as severely affected by A. flavus and aflatoxin contamination as other oilseed crops.     

Epigenetic tailoring for the production of anti-infective cytosporones from the marine fungus Leucostoma persoonii

Recent genomic studies have demonstrated that fungi can possess gene clusters encoding for the production of previously unobserved secondary metabolites. Activation of these attenuated or silenced genes to obtain either improved titers of known compounds or new ones altogether has been a subject of considerable interest. In our efforts to discover new chemotypes that are effective against infectious diseases, including malaria and methicillin-resistant Staphylococcus aureus (MRSA), we have isolated a strain of marine fungus, Leucostoma persoonii, that produces bioactive cytosporones. Epigenetic modifiers employed to activate secondary metabolite genes resulted in enhanced production of known cytosporones B (1, 360%), C (2, 580%) and E (3, 890%), as well as the production of the previously undescribed cytosporone R (4). Cytosporone E was the most bioactive, displaying an IC(90) of 13 μM toward Plasmodium falciparum, with A549 cytotoxicity IC(90) of 437 μM, representing a 90% inhibition therapeutic index (TI(90) = IC(90) A459/IC(90)P. falciparum) of 33. In addition, cytosporone E was active against MRSA with a minimal inhibitory concentration (MIC) of 72 μM and inhibition of MRSA biofilm at roughly half that value (minimum biofilm eradication counts, MBEC90, was found to be 39 μM).     

Variability of neutrophil and pulmonary alveolar macrophage function in swine

Neutrophils and alveolar macrophages are essential defence mechanisms against bacterial infection of the lung. The purpose of this study was to evaluate the variability of a panel of neutrophil and alveolar macrophage function assays in swine, and to determine if the function of these leukocytes differed at various stages of production. Measured neutrophil functions included chemotaxis, phagocytosis, oxidative burst, and degranulation. Phagocytosis and oxidative burst were measured in alveolar macrophages isolated from bronchoalveolar lavage fluid (BALF). Both neutrophil and alveolar macrophage functions were highly variable from day-to-day and between pigs. Individual pigs did not have consistently high or low neutrophil and macrophage responses over time when compared to their cohorts. Older grower-finisher pigs had significantly greater neutrophil oxidative burst responses than younger suckling and weaner pigs (P < 0.001). Similarly, alveolar macrophages from suckling and early weaner pigs less than 40 days of age had significantly lower oxidative burst responses than those from older pigs (P = 0.02). Age-related variation in phagocytosis, chemotaxis, or granule secretion were not detected. These results establish baseline data for individual and age-related variation in swine leukocyte function, and form a basis for further evaluation of the contribution of non-infectious factors to development of the porcine respiratory disease complex.     

Correlation between cytologic and histopathologic diagnoses of bone lesions in dogs: a study of the diagnostic accuracy of bone cytology

Background: The diagnostic value of cytology compared with histopathology varies by tissue, but there is little information regarding this comparison involving canine bone. Objectives: The objective of this retrospective study was to compare primary pathologic processes for cytology and histopathology of canine bone lesions. We adopted a proposed standardized format for reporting studies of diagnostic accuracy. Methods: A computer search of canine medical records at the University of Minnesota Veterinary Medical Center from September 2002 through October 2006 identified 52 bone cytology samples that had incisional (IncB) and/or excisional (ExcB) biopsy performed. The primary pathologic process was determined by evaluation of original reports. Cytologic vs IncB and cytologic vs ExcB were compared pairwise for agreement. Agreement was compared for neoplastic and non-neoplastic processes using the combined IncB/ExcB data, which included all ExcB (n=21) and IncB when that was the only biopsy available (n=31). Combined data were used to determine the effect of cytology cellularity on the diagnostic correlation. Results: The correlation in primary process between cytology and IncB was 71%, and for ExcB was 71%. For lesions with a cytologic diagnosis of neoplasia compared with the combined IncB/ExcB data set, cytology and histopathology agreed in 92% of cases, which was significantly greater (P<.0001, chi(2)) than the 27% for non-neoplastic processes. Cytology cellularity significantly affected rates of correlation (P=.026), with high, moderate, and poor cellularity samples having concordant primary processes in 88%, 77%, and 47% of cases, respectively. Conclusions: Cytologic diagnosis of neoplasia for samples collected from canine bone correlates better with histopathology than cytologic diagnosis of non-neoplastic proliferative processes or inflammation. Cytologic diagnoses from highly cellular samples are more likely to correlate with histopathology than those from less cellular samples.     

Altered capsaicin levels in domesticated chili pepper varieties affect the interaction between a generalist herbivore and its ectoparasitoid

Journal of Pest Science - Plant domestication has commonly reduced levels of secondary metabolites known to confer resistance against insects. Chili pepper is a special case because the fruits of...     

A comparison of carotenoid content and total antioxidant activity in catsup from several commercial sources in the United States

Samples of catsup from 13 commercial sources, representing at least 10 U.S. manufacturers, were analyzed for carotenoid content, antioxidant activity, and percentage solids. The solids content of these catsup brand samples varied from 26.31 to 38.06% solids. The lycopene content ranged from 59.42 to 183.36 microg, and total carotenoids were as high as 216.6 microg/g fresh weight, respectively. In addition, both hydrophilic and lipophilic antioxidant activities were measured using the Trolox equivalent antioxidant capacity (TEAC) assay. These measurements of samples of the various catsup brands ranged from 176.5 to 356.8 total TEAC units.     

Gender and resource management: Community supported agriculture as caring-practice

Interviews with Community Supported Agriculture (CSA) growers in Iowa, a majority of whom are women, shed light on the relationship between gender and CSA as a system of resource management. Growers, male and female alike, are differentiated by care and caring-practices. Care-practices, historically associated with women, place priority on local context and relationships. The concern of these growers for community, nature, land, water, soil, and other resources is manifest in care-motives and care-practices. Their specific mix of motives differs: providing safe and nutritious food, educating self and others, and building relationships with other growers, shareholder-members, and the land. Care-practices include reducing or eliminating chemical usage, encouraging or accepting beneficial insects and wildlife, building soil, and creating resource management partnerships with shareholder members. CSA, viewed through a lens of care, may offer a means of transcending gender stereotypes. This revised version was published online in June 2006 with corrections to the Cover Date.