1-O-Alkylglycerol Ethers from the Marine Sponge Guitarra abbotti and Their Cytotoxic Activity

The cytotoxicity-bioassay-guided fractionation of the ethanol extract from the marine sponge Guitarra abbotti, whose 1-O-alkyl-sn-glycerol ethers (AGEs) have not been investigated so far, led to the isolation of a complex lipid fraction containing, along with previously known compounds, six new lipids of the AGE type. The composition of the AGE fraction as well as the structures of 6 new and 22 previously known compounds were established using ¹H and ¹³C NMR, GC/MS, and chemical conversion methods. The new AGEs were identified as: 1-O-(Z-docos-15-enyl)-sn-glycerol (1), 1-O-(Z-docos-17-enyl)-sn-glycerol (2), 1-O-(Z-tricos-15-enyl)-sn-glycerol (3), 1-O-(Z-tricos-16-enyl)-sn-glycerol (4), 1-O-(Z-tricos-17-enyl)-sn-glycerol (5), and 1-O-(Z-tetracos-15-enyl)-sn-glycerol (6). The isolated AGEs show weak cytotoxic activity in THP-1, HL-60, HeLa, DLD-1, SNU C4, SK-MEL-28, and MDA-MB-231 human cancer cells. A further cytotoxicity analysis in JB6 P⁺ Cl41 cells bearing mutated MAP kinase genes revealed that ERK2 and JNK1 play a cytoprotective role in the cellular response to the AGE-induced cytotoxic effects.     

Virulence factors of avian pathogenic Escherichia coli isolated from broilers from the south of Brazil

Sixty-three Escherichia coli strains isolated from broilers with respiratory problems were examined for virulence factors, hemolysin synthesis ability, motility, hemagglutination capacity, operon pap presence, colicin production, and serum resistance. The capacity to hemagglutinate guinea pig erythrocytes was found in 53 (84.1%) of the samples, but only 30 (47.6%) agglutinated chicken erythrocytes. D-mannose-sensitive hemagglutination against guinea pig erythrocytes was found in 19 (30.2%) samples and against chicken erythrocytes, in 15 (23.8%) samples, whereas the D-mannose-resistant hemagglutination with guinea pig erythrocytes was found in 34 (54%) samples, and 13 of these (20.6%) showed this characteristic against chicken erythrocytes. Operon pap, P fimbria codifier, was detected in 26 samples in a total of 34 D-mannose-resistant samples. Colicin production was observed in 55 (87.3%) of the strains, and 41.8% presented V colicin production. Of the samples analyzed, 56 (88.9%) presented serum resistance, six (9.5%) were intermediate, and only one (1.6%) was sensitive to the action of the complement. The diversity of virulence profiles detected in the samples in this study explains in part the multifactorial characteristics of avian colibacillosis.     

Evidence for genetic diversity of Toxoplasma gondii in selected intermediate hosts in Serbia

To contribute to the insight into the worldwide population structure of Toxoplasma gondii, we genetically characterized a total of eight strains isolated from intermediate hosts including humans, sheep and pigeons in Serbia. Although parasite DNA was detected in 28.2% (60/213) of the human samples from 162 patients serologically suspected of active toxoplasmosis, as well as in 5/7 seropositive pigeons and in 2/12 seropositive sheep examined, multilocus PCR-RFLP genotyping, using SAG1, 5′SAG2, 3′SAG2, GRA6, 5′GRA7 and 3′GRA7 as markers, was successful in only four human isolates (of which one was isolated from both the bronchoalveolar lavage fluid and blood samples of a single patient), one sheep and three pigeons. Of the eight isolates, five were type II (62.5%), one was type III, one was atypical, and one had a type I allele at GRA6 as the single locus genotyped. Although type II, as elsewhere in Europe, predominated, these results may suggest a higher genetic diversity of T. gondii in Serbia, reflecting local environmental contamination and also the geographical position of the country in South-East Europe.     

Factors associated with fusarium crown and root rot of asparagus outbreaks in quebec

ABSTRACT The Fusarium spp. causing Fusarium crown and root rot (FCRR) are ubiquitous and abundant in soils, but in contrast, disease expression is localized and sporadic. Previous studies have related FCRR infection to phenolic acids released by asparagus, to the repression of Mn-reducers in soil, and to various soil physicochemical conditions. Fifty commercial asparagus plantations were surveyed using an exploratory approach in order to pinpoint the ecological conditions associated with FCRR development. Twenty-eight variables were used to describe the soil environments of the asparagus crops as well as the influence of crop management practices used locally. The data set was analyzed both as a whole and parsed by main cultivars (Jersey Giant and Guelph Millenium). Both field conditions and percentage of field area affected by FCRR varied widely between asparagus plantations. Planting depth was positively correlated with percentage of field area affected by FCRR and, hence, deep planting may favor FCRR infection. Plantation age was positively correlated with percentage of field area affected by FCRR, while soil available Mn was inversely correlated. Most importantly, soil Mn availability decreased with increasing plantation age, supporting the hypothesis of an asparagusmediated negative impact on Mn-reducing bacteria and of the involvement of reduced Mn availability in FCRR development. Improving the availability of Mn could provide a solution to the problem of FCRR in asparagus plantations.     

Analysis of genetic diversity among Macrophomina phaseolina (Tassi) Goid. isolates from Euro-Asian countries

Journal of Plant Diseases and Protection - The study assessed the genetic variability among Macrophomina phaseolina (Tassi) Goid. isolates originating from six different countries (Turkey,...     

Zero-inflated models for identifying disease risk factors when case detection is imperfect: Application to highly pathogenic avian influenza H5N1 in Thailand

Logistic regression models integrating disease presence/absence data are widely used to identify risk factors for a given disease. However, when data arise from imperfect surveillance systems, the interpretation of results is confusing since explanatory variables can be related either to the occurrence of the disease or to the efficiency of the surveillance system. As an alternative, we present spatial and non-spatial zero-inflated Poisson (ZIP) regressions for modelling the number of highly pathogenic avian influenza (HPAI) H5N1 outbreaks that were reported at subdistrict level in Thailand during the second epidemic wave (July 3rd 2004 to May 5th 2005). The spatial ZIP model fitted the data more effectively than its non-spatial version. This model clarified the role of the different variables: for example, results suggested that human population density was not associated with the disease occurrence but was rather associated with the number of reported outbreaks given disease occurrence. In addition, these models allowed estimating that 902 (95% CI 881–922) subdistricts suffered at least one HPAI H5N1 outbreak in Thailand although only 779 were reported to veterinary authorities, leading to a general surveillance sensitivity of 86.4% (95% CI 84.5–88.4). Finally, the outputs of the spatial ZIP model revealed the spatial distribution of the probability that a subdistrict could have been a false negative. The methodology presented here can easily be adapted to other animal health contexts.     

The occurrence of reflexes and reactions in cattle following stunning with a captive bolt at the slaughterhouse

The difference in the frequency of the occurrence of reflexes/reactions in 355 cows (average weight 505.5 ± 7.9 kg) and 262 bulls (average weight 735.6 ± 8.4 kg) following stunning with a Matador SS 3,000 B trigger‐activated captive bolt gun (Termet) was determined. The stun shot more than 2 cm from the ideal position was found in 79.6% of animals. Vocalization, corneal reflex, rhythmic breathing, blinking, eyeball rotation and the absence of tongue protrusion occurred more frequently in bulls (p < .05). Spontaneous limb movements and nystagmus occurred more frequently in cows (p < .05). No difference between bulls and cows was determined in the occurrence of a response to painful stimuli or attempts to regain normal posture. No dependency was determined between the frequency of the occurrence of a reflex/reaction and the distance of the stun shot from the ideal point on the skull for any of the monitored signs. This study shows that the occurrence of reflexes/reactions following the stunning of cattle with a captive bolt is not only dependent on the position of the shot if placed within a 9 cm radius from the ideal point on the cattle skull.     

The effects of chronic intermittent noise exposure on broiler chicken performance

Effects of different noise levels (70 or 80 dB) that broilers were exposed to during the entire fattening period and also the effect of the timing of the first exposure to intermittent noise in the course of fattening (day 1 vs. day 7) were monitored. After 7 days of exposure to intermittent noise, experimental chickens already showed a significant decrease in live body weight in comparison with the control group. The difference between the group exposed to intermittent noise at 70 dB and the group exposed to 80 dB levels was not statistically significant, although the mean live body weight of broilers in the latter was lower during the entire fattening period. The chickens exposed to intermittent noise from day 1 of age showed lower mean live weight throughout the fattening period compared to chickens exposed to the same level of intermittent noise only from day 7 of age, although at the end of fattening the difference was statistically significant only in chickens exposed to the higher level of intermittent noise (80 dB).     

Generalized functions of biomass expansion factors for conifers and broadleaved by stand age,growing stock and site index

Parties to the Kyoto Protocol and/or the United Nations Framework Convention on Climate Change (UNFCCC) are required to account for their direct human-induced carbon emissions and removals including those from forestry and other land use related activities. In most European countries, the forestry related greenhouse gas inventories are largely or exclusively based on converting tree volume data from national forest inventories to biomass using biomass conversion and expansion factors (BCEFs). However, country specific data for many species are often lacking, which considerably increases the uncertainties of the greenhouse gas inventories. The focus of this research was to develop, using internationally published datasets that cover a large geographical area, an extended set of generalized curves of such biomass expansion factors for several species or species groups by age, growing stock and site index.