Thermal stress responses in Antarctic yeast, Glaciozyma antarctica PI12, characterized by real-time quantitative PCR

Living organisms have some common and unique strategies to response to thermal stress. However, the amount of data on thermal stress response of certain organism is still lacking, especially psychrophilic yeast from the extreme habitat. Therefore, it is not known whether psychrophilic yeast shares the common responses of other organisms when exposed to thermal stresses. In this work, the cold shock and heat shock responses in Antarctic psychrophilic yeast Glaciozyma antarctica PI12 which had an optimal growth temperature of 12 °C were determined. The expression levels of 14 thermal stress-related genes were measured using real-time quantitative PCR (qPCR) when the yeast cells were exposed to cold shock (0 °C), mild cold shock (5 °C), and heat shock (22 °C) conditions. The expression profiles of the 14 genes at these three temperatures varied indicating that these genes had their specific roles to ensure the survival of the yeast. Under cold shock condition, the afp4 and fad genes were over-expressed possibly as a way for the G. antarctica PI12 to avoid ice crystallization in the cell and to maintain the membrane fluidity. Under the heat shock condition, hsp70 was significantly up-regulated possibly to ensure the proteins fold properly. Among the six oxidative stress-related genes, MnSOD and prx were up-regulated under cold shock and heat shock, respectively, possibly to reduce the negative effects caused by oxidative stress. Interestingly, it was found that the trehalase gene, nth1 that plays a role in degrading excess trehalose, was down-regulated under the heat shock condition possibly as an alternative way to accumulate trehalose in the cells to protecting them from being damaged.     

A high-oleic-acid and low-palmitic-acid soybean: agronomic performance and evaluation as a feedstock for biodiesel

Phenotypic characterization of soybean event 335-13, which possesses oil with an increased oleic acid content (> 85%) and reduced palmitic acid content (< 5%), was conducted across multiple environments during 2004 and 2005. Under these conditions, the stability of the novel fatty acid profile of the oil was not influenced by environment. Importantly, the novel soybean event 335-13 was not compromised in yield in both irrigated and non-irrigated production schemes. Moreover, seed characteristics, including total oil and protein, as well as amino acid profile, were not altered as a result of the large shift in the fatty acid profile. The novel oil trait was inherited in a simple Mendelian fashion. The event 335-13 was also evaluated as a feedstock for biodiesel. Extruded oil from event 335-13 produced a biodiesel with improved cold flow and enhanced oxidative stability, two critical fuel parameters that can limit the utility of this renewable transportation fuel.     

Is carbonic anhydrase inhibition useful as a complementary therapy of Covid-19 infection?

The ongoing Covid-19 is a contagious disease, and it is characterised by different symptoms such as fever, cough, and shortness of breath. Rising concerns about Covid-19 have severely affected the healthcare system in all countries as the Covid-19 outbreak has developed at a rapid rate all around the globe. Intriguing, a clinically used drug, acetazolamide (a specific inhibitor of carbonic anhydrase, CA, EC 4.2.1.1), is used to treat high-altitude pulmonary oedema (HAPE), showing a high degree of clinical similarities with the pulmonary disease caused by Covid-19. In this context, this preliminary study aims to provide insights into some factors affecting the Covid-19 patients, such as hypoxaemia, hypoxia as well as the blood CA activity. We hypothesise that patients with Covid-19 problems could show a dysregulated acid–base status influenced by CA activity. These preliminary results suggest that the use of CA inhibitors as a pharmacological treatment for Covid-19 may be beneficial.     

Secondary succession impairment in restored mangroves

In this work it was hypothesized that secondary succession on sites that have been managed by single planting of mangrove species is compromised by residual stressors, which could reduce the ecosystem??s structural development and lower its functions. Forest structure and environmental characteristics of three planted mangrove stands are compared with reference sites. Structural attributes showed significant differences in the comparison of planted and reference stands. Avicennia schaueriana was the dominant species within both natural regeneration and old-growth stands in terms of basal area (99.2 and 99.4?%, 69.6 and 84.5?%, and 59.0 and 87.1?% for Itacorubi, Saco Grande, and Ratones, respectively). Restoration stands were dominated by Laguncularia racemosa (80.6 and 94.2?% for Saco Grande and Ratones, respectively), except at one site (Itacorubi), where A. schaueriana prevailed (99.7?%). Even though restoration and regeneration stands at Itacorubi showed similar species composition and dominance, cohort sorting revealed an inferior regeneration potential in the restoration stand. Multiple correlation analysis indicated that variables related to elevation disruptions (p _w ?=?0.521) were the environmental drivers responsible for the differences observed in forest structure. At restoration sites an impaired pattern of secondary succession was observed, indicating that single species plantings may be ineffective if characteristics of the site, as well as of the area surrounding it, are not considered. The inadequate management of restoration sites can therefore have implications for both immediate and long-term large-scale ecosystem services.     

Putaminoxin, a phytotoxic nonenolide from Phoma putaminum

Phoma putaminum, the causal agent of leaf necrosis of Erigeron annuus, a common weed of field and pasture, produced toxic metabolites when grown in liquid culture. The main phytotoxin, named putaminoxin, was isolated and characterized using spectroscopic and chemical methods as (5S)5-hydroxy-9-propyl-6-nonen-9-olide, a new 10-macrolide. When assayed on leaves of host and non-host plants, putaminoxin showed a wide range of toxicity, with leaves of E. annuus being most sensitive.     

The scaling of ground reaction forces and duty factor in monitor lizards: implications for locomotion in sprawling tetrapods

Geometric scaling predicts a major challenge for legged, terrestrial locomotion. Locomotor support requirements scale identically with body mass (α M¹), while force-generation capacity should scale α M^2/3 as it depends on muscle cross-sectional area. Mammals compensate with more upright limb postures at larger sizes, but it remains unknown how sprawling tetrapods deal with this challenge. Varanid lizards are an ideal group to address this question because they cover an enormous body size range while maintaining a similar bent-limb posture and body proportions. This study reports the scaling of ground reaction forces and duty factor for varanid lizards ranging from 7 g to 37 kg. Impulses (force×time) (α M^0.99−1.34) and peak forces (α M^0.73−1.00) scaled higher than expected. Duty factor scaled α M^0.04 and was higher for the hindlimb than the forelimb. The proportion of vertical impulse to total impulse increased with body size, and impulses decreased while peak forces increased with speed.     

Impairment of Myocyte Contractility Following Coronary Artery Narrowing Is Associated with Activation of the Myocyte IGF1 Autocrine System, Enhanced Expression of Late Growth Related Genes, DNA Synthesis, and Myocyte Nuclear Mitotic Division in Rats

To determine whether the alterations in ventricular loading and myocyte cellular contractile performance produced by short-term coronary artery constriction were associated with the activation of genes implicated in myocyte DNA synthesis including changes in the expression of insulin-like growth factor-1 (IGF₁) and insulin-like growth factor-1 receptors (IGF₁-R), nonocclusive coronary artery narrowing (CAN) was induced in rats. Animals were examined 2 and 7 days after coronary constriction. Following the in vivo documentation of severe impairment of ventricular performance, estimations of single-cell mechanics in vitro showed that peak shortening was decreased in left and right myocytes of coronary stenosed rats. Moreover, time to peak shortening was prolonged whereas velocity of shortening was decreased. These defects in myocyte contractility were accompanied by increases in cell length and width, indicative of myocyte enlargement biventricularly. In addition, CAN led to an enhanced expression of proliferating cell nuclear antigen (PCNA) and histone-H₃ genes in myocytes at 2 and 7 days after surgery. PCNA protein was also detected in these stressed cells. These molecular responses were associated with increases in mRNA for IGF₁ and IGF₁-R in combination with enhanced DNA synthesis and appearance of myocyte nuclear mitotic division. In conclusion, cardiac myocytes may respond to the elevation in wall and myocyte stress by activating an IGF₁-IGF₁-R autocrine system which may modulate the induction of late growth related genes which are essential for DNA replication and myocyte cellular hyperplasia.     

Ceruloplasmin serum level in post-menopausal women treated with oral estrogens administered at different times.

The liver is an estrogen-responsive organ and the administration of estrogens in humans increases the hepatic synthesis of many proteins. The existence of a circadian rhythm of estrogen receptors in the liver has been proved by different authors. We studied the presence of a different responsiveness of the human liver to the estrogens in two groups of post-menopausal women by evaluating the changes in ceruloplasmin serum level. Conjugated equine estrogens were administered at different times (A: 8 a.m. and B: 8 p.m.). The replacement therapy increased ceruloplasmin serum levels both in group A and B, but the increase was higher in group B than in group A. These data reflect indirectly the presence of a circadian rhythm of hepatic responsiveness to the estrogens.     

From Innovation to Diversification: A Simple Competitive Model

Few attempts have been proposed in order to describe the statistical features and historical evolution of the export bipartite matrix countries/products. An important standpoint is the introduction of a products network, namely a hierarchical forest of products that models the formation and the evolution of commodities. In the present article, we propose a simple dynamical model where countries compete with each other to acquire the ability to produce and export new products. Countries will have two possibilities to expand their export: innovating, i.e. introducing new goods, namely new nodes in the product networks, or copying the productive process of others, i.e. occupying a node already present in the same network. In this way, the topology of the products network and the country-product matrix evolve simultaneously, driven by the countries push toward innovation.     

Estimation of the deamidation rate of asparagine side chains.

Statistical analysis of data from the literature concerning the deamidation reaction of asparagine side-chains in short peptides reveals that the logarithm of rate constants can be solved into a constant plus contributions from the residues closest to asparagine. A table of amino acid contributions has been derived, from which deamidation rate constants can be estimated with good approximation. Assuming the contribution of glycine to be zero, the mean of the absolute values of the contributions for the residues following asparagine is approximately seven times that for the preceding residues. In both positions residues with no bulk side chains or with functional side groups contribute markedly to the increase in the rate constant.