Field-Isolated Genotypes of Mycobacterium bovis Vary in Virulence and Influence Case Pathology but Do Not Affect Outbreak Size

Strains of many infectious agents differ in fundamental epidemiological parameters including transmissibility, virulence and pathology. We investigated whether genotypes of Mycobacterium bovis (the causative agent of bovine tuberculosis, bTB) differ significantly in transmissibility and virulence, combining data from a nine-year survey of the genetic structure of the M. bovis population in Northern Ireland with detailed records of the cattle population during the same period. We used the size of herd breakdowns as a proxy measure of transmissibility and the proportion of skin test positive animals (reactors) that were visibly lesioned as a measure of virulence. Average breakdown size increased with herd size and varied depending on the manner of detection (routine herd testing or tracing of infectious contacts) but we found no significant variation among M. bovis genotypes in breakdown size once these factors had been accounted for. However breakdowns due to some genotypes had a greater proportion of lesioned reactors than others, indicating that there may be variation in virulence among genotypes. These findings indicate that the current bTB control programme may be detecting infected herds sufficiently quickly so that differences in virulence are not manifested in terms of outbreak sizes. We also investigated whether pathology of infected cattle varied according to M. bovis genotype, analysing the distribution of lesions recorded at post mortem inspection. We concentrated on the proportion of cases lesioned in the lower respiratory tract, which can indicate the relative importance of the respiratory and alimentary routes of infection. The distribution of lesions varied among genotypes and with cattle age and there were also subtle differences among breeds. Age and breed differences may be related to differences in susceptibility and husbandry, but reasons for variation in lesion distribution among genotypes require further investigation. © 2013 Wright et al.

Culture Age, temperature, and pH affect the polyol and trehalose contents of fungal propagules

The growth and conidial physiology of the entomopathogenic fungi Beauveria bassiana, Metarhizium anisopliae, and Paecilomyces farinosus were studied under different conditions. The effects of culture age (up to 120 days), temperature (5 to 35°C), and pH (2.9 to 11.1) were determined. Growth was optimal at pH 5 to 8 for each isolate and between 20 and 35°C, depending on the isolate. The predominant polyol in conidia was mannitol, with up to 39, 134, and 61 mg g of conidia-1 for B. bassiana, M. anisopliae, and P. farinosus, respectively. Conidia of M. anisopliae contained relatively small amounts of lower-molecular-weight polyols and trehalose (less than 25 mg g-1 in total) in all treatments. Conidia of B. bassiana and P. farinosus contained up to 30, 32, and 25 mg of glycerol, erythritol, and trehalose, respectively, g-1, depending on the treatment. Conidia of P. farinosus contained unusually high amounts of glycerol and erythritol at pH 2.9. The apparent effect of pH on gene expression is discussed in relation to the induction of a water stress response. To our knowledge, this is the first report of polyols and trehalose in fungal propagules produced over a range of temperature or pH. Some conditions and harvesting times were associated with an apparent inhibition of synthesis or accumulation of polyols and trehalose. This shows that culture age and environmental conditions affect the physiological quality of inoculum and can thereby determine its potential for biocontrol.

Grazing under experimental hypercapnia and elevated temperature does not affect the radula of a chiton (Mollusca, Polyplacophora, Lepidopleurida)

Chitons (class Polyplacophora) are benthic grazing molluscs with an eight-part aragonitic shell armature. The radula, a serial tooth ribbon that extends internally more than half the length of the body, is mineralised on the active feeding teeth with iron magnetite apparently as an adaptation to constant grazing on rocky substrates. As the anterior feeding teeth are eroded they are shed and replaced with a new row. The efficient mineralisation and function of the radula could hypothetically be affected by changing oceans in two ways: changes in seawater chemistry (pH and pCO(2)) may impact the biomineralisation pathway, potentially leading to a weaker or altered density of the feeding teeth; rising temperatures could increase activity levels in these ectothermic animals, and higher feeding rates could increase wear on the feeding teeth beyond the animals' ability to synthesise, mineralise, and replace radular rows. We therefore examined the effects of pH and temperature on growth and integrity in the radula of the chiton Leptochiton asellus. Our experiment implemented three temperature (similar to 10, 15, 20 degrees C) and two pCO(2) treatments (similar to 400 mu atm, pH 8.0; similar to 2000 mu atm, pH 7.5) for six treatment groups. Animals (n = 50) were acclimated to the treatment conditions for a period of 4 weeks. This is sufficient time for growth of ca. 7-9 new tooth rows or 20% turnover of the mineralised portion. There was no significant difference in the number of new (non-mineralised) teeth or total tooth row count in any treatment. Examination of the radulae via SEM revealed no differences in microwear or breakage on the feeding cusps correlating to treatment groups. The shell valves also showed no signs of dissolution. As a lineage, chitons have survived repeated shifts in Earth's climate through geological time, and at least their radulae may be robust to future perturbations.

Burkholderia cenocepacia Lipopolysaccharide Modification and Flagellin Glycosylation Affect Virulence but Not Innate Immune Recognition in Plants

Burkholderia cenocepacia causes opportunistic infections in plants, insects, animals, and humans, suggesting that “virulence” depends on the host and its innate susceptibility to infection. We hypothesized that modifications in key bacterial molecules recognized by the innate immune system modulate host responses to B. cenocepacia. Indeed, modification of lipo- polysaccharide (LPS) with 4-amino-4-deoxy-L-arabinose and flagellin glycosylation attenuates B. cenocepacia infection in Arabi- dopsis thaliana and Galleria mellonella insect larvae. However, B. cenocepacia LPS and flagellin triggered rapid bursts of nitric oxide and reactive oxygen species in A. thaliana leading to activation of the PR-1 defense gene. These responses were drastically reduced in plants with fls2 (flagellin FLS2 host receptor kinase), Atnoa1 (nitric oxide-associated protein 1), and dnd1-1 (reduced production of nitric oxide) null mutations. Together, our results indicate that LPS modification and flagellin glycosylation do not affect recognition by plant receptors but are required for bacteria to establish overt infection.

How Critical Care Nurses' Role and Education Affect Organ Donation

Organ and tissue dysfunction and failure cause high mortality rates around the world. Tissue and organs transplantation is an established, cost-effective, life-saving treatment for patients with organ failure. However, there is a large gap between the need for and the supply of donor organs. Acute and critical care nurses have a central role in the organ donation process, from identifying and assessing potential donors and supporting their families to involvement in logistics. Nurses with an in-depth knowledge of donation understand its clinical and technical aspects as well as the moral and legal considerations. Nurses have a major role to play in tackling organ and tissue shortages. Such a role cannot be adequately performed if nurses are not fully educated about donation and transplant. Such education could be incorporated into mandatory training and completed by all nurses.

Tyrosine phosphorylation and dephosphorylation in Burkholderia cenocepacia affect biofilm formation, growth under nutritional deprivation, and pathogenicity

Burkholderia cenocepacia, a member of the B. cepacia complex (Bcc), is an opportunistic pathogen causing serious chronic infections in patients with cystic fibrosis. Tyrosine phosphorylation has emerged as an important post-translational modification modulating the physiology and pathogenicity of Bcc bacteria. Here, we investigated the predicted bacterial tyrosine kinases BCAM1331 and BceF, and the low molecular weight protein tyrosine phosphatases BCAM0208, BceD and BCAL2200 of B. cenocepacia K56-2. We show that BCAM1331, BceF, BCAM0208 and BceD contributed to biofilm formation, while BCAL2200 was required for growth in nutrient-limited conditions. Multiple deletions of either tyrosine kinase or low molecular weight protein tyrosine phosphatases genes resulted in attenuation of B. cenocepacia intramacrophage survival and reduced pathogenicity in the Galleria mellonella larvae infection model. Experimental evidence indicates that BCAM1331 displays a reduced
tyrosine autophosphorylation activity compared to BceF. Using the artificial substrate p-nitrophenyl phosphate, the phosphatase activity of the three low molecular weight protein tyrosine phosphatases demonstrated similar kinetic parameters. However, only BCAM0208 and BceD could dephosphorylate BceF. Further, BCAL2200 becomes tyrosine phosphorylated in vivo and catalyzes its auto-dephosphorylation. Together, our data suggest that despite having similar biochemical activities low molecular weight protein tyrosine phosphatases and tyrosine kinases have both overlapping and specific roles in the physiology of B. cenocepacia.

How does globalization affect the tax burden on labour income, capital income and consumption in different welfare regimes? The case of Western and Eastern EU Member States

This article analyzes the effects of globalization on implicit tax rates (ITRs) on labor income, capital income, and consumption in the EU15 and Central and Eastern European New Member States (CEE NMS). We find supportive evidence for an increase in the ITR on labor income in the EU15, but no effect on the ITR on capital income. There is evidence of convergence in terms of the ITR on consumption, as countries with higher than average ITR on consumption respond to globalization by decreasing their tax rates. There are important differences among the welfare regimes within the EU15. Social-democratic countries have decreased the tax burden on capital, but increased that on labor due to globalization. Globalization exerts a pressure to increase taxes on labor income in the conservative and liberal regimes as well. Taxes on consumption decrease in response to globalization in the conservative and social-democratic regimes. In the CEE NMS, there is no effect of globalization on the ITR on labor and capital income, but we find a negative impact on the ITR on consumption in the CEE NMS with higher than average ITR on consumption. (JEL H23, H24, H25, F19, F21)

Do financial distress and liquidity crises affect value and size premiums?

This study investigates the impact of liquidity crises on the relationship between stock (value and size) premiums and default risk in the US market. It first examines whether financial distress can explain value and size premiums, and then, subsequently, aims to determine whether liquidity crises increase the risk of value and size premium investment strategies. The study employs a time-varying approach and a sample of US stock returns for the period between January 1982 and March 2011, a period which includes the current liquidity crisis, so as to examine the relationship between default risk, liquidity crises and value and size premiums. The findings indicate that the default premium has explanatory power for value and size and premiums, which affect firms with different characteristics. We also find that liquidity crises may actually increase the risks related to size and value premium strategies.

Shiva's dance: Crisis, local institutions and private firms

The uneven spatial distribution of start-ups and their respective survival may reflect comparative advantages resulting from the local institutional background. For the first time, we explore this idea using Data Envelopment Analysis (DEA) to assess the relative efficiency of Portuguese municipalities in this specific context. We depart from the related literature where expenditure is perceived as a desirable input by choosing a measure of fiscal responsibility and infrastructural variables in the first stage. Comparing results for 2006 and 2010, we find that mean performance decreased substantially 1) with the effects of the Global Financial Crisis, 2) as municipal population increases and 3) as financial independence decreases. A second stage is then performed employing a double-bootstrap procedure to evaluate how the regional context outside the control of local authorities (e.g. demographic characteristics and political preferences) impacts on efficiency.

Does the existing Corporate Governance structure and strict Legal Framework, affect the strategic decisionmaking of CEOs?

This thesis is a case study on Corporate Governance and Business Ethics, using the Portuguese Corporate Law as a general setting. The thesis was conducted in Portugal with illustrations on past cases under the Business Judgment Rule of the State of Delaware, U.SA along with illustrations on current cases in Portugal under the Portuguese Judicial setting, along with a comparative analysis between both. A debate is being considered among scholars and executives; a debate on best practices within corporate governance and corporate law, associated with recent discoveries of unlawful investments that lead to the bankruptcy of leading institutions and an aggravation of the crisis in Portugal. The study aimed at learning possible reasons and causes for the current situation of the country’s corporations along with attempts to discover the best way to move forward. From the interviews and analysis conducted, this paper concluded that the corporate governance structure and legal frameworks in Portugal were not the sole influencers behind the actions and decisions of Corporate Executives, nor were they the main triggers for the recent corporate mishaps. But it is rather a combination of different factors that played a significant role, such as cultural and ethical aspects, individual personalities, and others all of which created gray areas beyond the legal structure, which in turn accelerated and aggravated the corporate governance crisis in the country.