Lactococcus garvieae in fish: a review

Lactococcus garvieae is the etiological agent of Lactococcosis, an emergent disease which affects many fish species and causes important economic losses both in marine and freshwater aquaculture when water temperature increases over 16 degrees C in summer months. Normally, it causes a hyperacute and haemorrhagic septicemia. This paper presents a state of the art review of fish Lactococcosis including aspects such as pathogen characterization, pathogenesis, epidemiology, diagnosis and control measures of the disease in farmed fish.     

Genotype-by-trait association of sorghum (Sorghum bicolor (L.) Moench) advanced lines grown under arid and semi-arid regions of Zimbabwe

Journal of Crop Science and Biotechnology - Inadequate information is available on trait relations and profiles of sorghum genotypes, yet this information is vital for precise decisions to be...     

Influence of Enchytraeidae (Enchytraeus albidus) and compaction on nutrient mobilization in an urban soil

Soil compaction is an often-recorded characteristic of degraded soils, and—along with soil sealing and contamination—frequently found in urban habitats. Knowledge about the impact of soil degradation on the ecosystem functioning in urban environments is limited, although urbanization is the major ongoing land use change worldwide. Since urban soils are a potential habitat for soil animals, and burrowing soil fauna exerts a profound impact on the structure and functioning of soils, we studied the impact of increased bulk densities on the ability of Enchytraeus albidus (Enchytraeidae: Oligochaeta) to penetrate compacted soils. Moreover, it was our aim to characterize the influence of the worms on the mobilization of nutrients in urban soils. E. albidus was able to enter compacted sandy loamy soil columns with a bulk density of up to approx. 1.4 g cm⁻³, but only up to approx. 1.0 g cm⁻³ in pure sandy soil columns. Soil compaction increased the amounts of water-extractable sodium (7.5%) and magnesium (13.4%) compared to the non-compacted soil. Presence of E. albidus in the non-compacted soil resulted in higher water-extractable concentrations of sodium (17.4%), potassium (16.8%), calcium (11.3%), magnesium (13.2%), dissolved organic carbon (DOC, 14.5%) and nitrate (20.4%) in soil extracts. In the compacted soil, however, the enhanced nutrient availability due to the activity of the enchytraeids was less pronounced than in the non-compacted soil. Although the concentrations of DOC (13.5%), nitrate (15.6%), calcium (5.8%) and magnesium (4.0%) were significantly higher in the presence of E. albidus than in the columns without animals, the performance of the animals was partly impaired. This was most likely due to the higher penetration resistance of the compacted soils. The degree of compaction investigated in this study was relatively low-chosen to allow for the colonization of the soils by E. albidus. We conclude that the observed negative effects of increased bulk densities on the activity of soil enchytraeids can occur in any more frequented city park, thereby decreasing turnover rates and the supply of soil nutrients in urban ecosystems.     

Plasmid DNA immunization with Trypanosoma cruzi genes induces cardiac and clinical protection against Chagas disease in the canine model

The only existing preventive measure against American trypanosomosis, or Chagas disease, is the control of the transmitting insect, which has only been effective in a few South American regions. Currently, there is no vaccine available to prevent this disease. Here, we present the clinical and cardiac levels of protection induced by expression to Trypanosoma cruzi genes encoding the TcSP and TcSSP4 proteins in the canine model. Physical examination, diagnostic chagasic serology, and serial electrocardiograms were performed before and after immunization, as well as after experimental infection. We found that immunization with recombinant plasmids prevented hyperthermia in the acute phase of experimental infection and produced lymphadenomegaly as an immunological response against the parasite and additionally prevented heart rate elevation (tachycardia) in the acute and/or chronic stages of infection. Immunization with T. cruzi genes encoding the TcSP and TcSSP4 antigens diminished the quality and quantity of the electrocardiographic abnormalities, thereby avoiding progression to more severe developments such as right bundle branch block or ventricular premature complexes in a greater number of dogs.     

The antidepressant fluoxetine restores plasticity in the adult visual cortex

We investigated whether fluoxetine, a widely prescribed medication for treatment of depression, restores neuronal plasticity in the adult visual system of the rat. We found that chronic administration of fluoxetine reinstates ocular dominance plasticity in adulthood and promotes the recovery of visual functions in adult amblyopic animals, as tested electrophysiologically and behaviorally. These effects were accompanied by reduced intracortical inhibition and increased expression of brain-derived neurotrophic factor in the visual cortex. Cortical administration of diazepam prevented the effects induced by fluoxetine, indicating that the reduction of intracortical inhibition promotes visual cortical plasticity in the adult. Our results suggest a potential clinical application for fluoxetine in amblyopia as well as new mechanisms for the therapeutic effects of antidepressants and for the pathophysiology of mood disorders.     

Preparation of lignopolyols from wheat straw soda lignin

Wheat straw soda lignin was modified and characterized by several qualitative and quantitative methods such as (31)P NMR spectroscopy to evaluate its potential as a substitute for polyols in view of polyurethane applications. Chemical modification of the lignin was achieved with propylene oxide to form lignopolyol derivatives. This was performed by a two-step reaction of lignin with maleic anhydride followed by propylene oxide and by direct oxyalkylation under acidic and alkaline conditions. The physical and chemical properties of lignopolyols from each method and the subsequent chain-extended hydroxyl groups were evaluated. Direct oxyalkylation of lignin under alkaline conditions was found to be more efficient than acidic conditions and more effective than the two-step process for preparing lignopolyol with higher aliphatic hydroxyl contents.     

A study of the prevalence of methicillin-resistant Staphylococcus aureus in pigs and in personnel involved in the pig industry in Ireland

To evaluate the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in the pig population in Ireland, nasal swabbing was employed in three abattoirs to screen 440 pigs from 41 geographically distributed farms. One hundred individuals involved in the pig industry were also nasally screened. No MRSA isolates were recovered from the pigs and only two of the humans tested were identified as MRSA carriers. Importantly, MRSA was not obtained from pig producers, veterinarians or abattoir employees, but was isolated from individuals working in the wider pig industry. Multi-locus sequence typing revealed that these isolates belonged to sequence types (ST) ST22 and ST1307; the latter is a previously unreported single locus variant of ST5. Five dust samples from each of the three slaughterhouses were culture-negative for MRSA. These results indicate that porcine colonisation by MRSA, and in particular the animal-related strain MRSA-ST398, was not common in Ireland during the period of study.