Can GM sorghum impact Africa?

It is said that genetic modification (GM) of grain sorghum has the potential to alleviate hunger in Africa. To this end, millions of dollars have been committed to developing GM sorghum. Current developments in the genetic engineering of sorghum are similar to efforts to improve cassava and other traditional African crops, as well as rice in Asia. On closer analysis, GM sorghum is faced with the same limitations as 'Golden Rice' (GM rice) in the context of combating vitamin A deficiency (VAD) efficiently and sustainably. Thus, it is questionable whether the cost of developing GM sorghum can be justified when compared to the cost of investing in sustainable agricultural practice in Africa.     

Protozoan grazing of bacteria in soil—impact and importance

Interactions between bacteria and protozoa in soil were studied over 2-week periods in the field and in a pot experiment. Under natural conditions the total biological activity was temporarily synchronized by a large rainfall, and in the laboratory by the addition of water to dried-out soil, with or without plants. In the field, peaks in numbers and biomass of bacteria appeared after the rain, and a peak of naked amoebae quickly followed. Of the three investigated groups—flagellates, ciliates, and amoebae—only populations of the latter were large enough and fluctuated in a way that indicated a role as bacterial regulators. The bacterial increase was transient, and the amoebae alone were calculated to be able to cause 60% of the bacterial decrease. The same development of bacteria and protozoa was observed in the pot experiment: in the presence of roots, amoebic numbers increased 20 times and became 5 times higher than in the unplanted soil. In the planted pots, the amoebic increase was large enough to cause the whole bacterial decrease observed; but in the unplanted soil, consumption by the amoebae caused only one-third of the bacterial decrease.     

Does corn market uncertainty impact the US ethanol prices?

The growing interest in biofuel as a green energy source has intensified the linkages between corn and ethanol markets, especially in the United States that represents the largest producing and exporting country for ethanol in the world. In this study, we examine the effect of corn market uncertainty on the price changes of US ethanol applying a set of GARCH‐jump models. We find that the US ethanol price changes react positively to the corn market volatility shocks after controlling for the effect of oil price uncertainty. In addition, we document that the impact of corn price volatility on the US ethanol prices appears to be asymmetric. Specifically, only the positive corn market volatility shocks are found to influence the ethanol market returns. Our findings also suggest that time‐varying jumps do exist in the ethanol market.     

Correlative video-light–electron microscopy: development,impact and perspectives

Green fluorescent protein (GFP)-based video microscopy can provide profound insight into biological processes by generating information on the ‘history,’ or dynamics, of the cellular structures involved in such processes in live cells. A crucial limitation of this approach, however, is that many such structures may not be resolved by light microscopy. Like more recent super-resolution techniques, correlative video-light–electron microscopy (CLEM) was developed to overcome this limitation. CLEM integrates GFP-based video microscopy and electron microscopy through a series of ancillary techniques, such as proper fixation, hybrid labeling and retracing, and so provides sufficient resolution as well as, crucially, cellular ‘context’ to the fluorescent dynamic structures of interest. CLEM ‘multiplies’ the power of video microscopy and is having an important impact in several areas cell and developmental biology. Here, we discuss potential, limitations and perspectives of correlative approaches aimed at integrating the unique insight generated by video microscopy with information from other forms of imaging.     

Prognostic impact of Metadherin–SND1 interaction in colon cancer

The interaction between Metadherin (MTDH) and Staphylococcal nuclease homology domain containing 1 (SND1) is involved in tumorigenesis and tumor progression of several human malignancies. However, its roles in colon cancer are still unclear. To investigate the clinical value of MTDH and SND1 expression in colon cancer. Immunohistochemical staining was performed to detect the expression of MTDH and SND1 using human colon cancer and their corresponding non-cancerous colon tissues from 196 patients’ biopsies. Positive expression of MTDH and SND1 were both increased in colon cancer tissues compared to paired non-cancerous colon tissues. There was a positive correlation between MTDH and SND1 expression in colon cancer tissues (r?=?0.86, p?<?0.001). In addition, their positive expression were both significantly associated with nodal status (both p?=?0.02), pathological stage (p?=?0.006 and 0.008, respectively) and differentiation (both p?=?0.03). Moreover, the overall survival in colon cancer patients with positive expression of MTDH and SND1 were significantly shorter than those without their expression (both p?=?0.01). Furthermore, multivariate Cox regression analysis suggested that positive expression of MTDH and SND1 was an independent poor prognostic predictor in colon cancer. Our data suggest that the increased expression of MTDH and/or SND1 is closely related to carcinogenesis, progression, and prognosis of colon cancer. The co-expression of MTDH/SND1 may be a novel distinctive marker to benefit us in prediction of the prognosis in colon cancer.     

Does lemming winter grazing impact vegetation in the Canadian Arctic?

In low-productivity environments such as the tundra, it has been proposed that regular, multi-annual population cycles of lemmings could be driven by winter food depletion in years of peak abundance. If lemming population dynamics is controlled by food resources, we predict that (1) winter grazing should negatively impact the abundance of food plants, (2) this impact should be proportional to lemming density and (3) high lemming winter grazing pressure should result in reduced plant growth during the following summer. We tested these predictions on Bylot Island, Nunavut, Canada, where two species of lemmings are present: the brown (Lemmus trimucronatus) and collared lemming (Dicrostonyx groenlandicus). We installed 16 exclosures in their preferred wintering habitat (snowbeds) and annually sampled plant biomass inside and outside exclosures at snow melt and at peak growth during the summers of 2009–2012, covering a full population cycle. Winter grazing had no impact on total vascular plant or moss biomass at snow melt in all years. Among plant families, only Caryophyllaceae, which was uncommon, showed a decline. In moss taxa, a negative effect was found on Polytrichum in only 1 year out of three. Overall, plant regrowth during the subsequent summer showed annual variation and tended to be reduced in the 2 years of high lemming abundance. However, this could be a consequence of summer grazing. Overall, the impact of lemming winter grazing on plants was weak and short-lived, even in years of high lemming abundance. Therefore, our results are not consistent with the hypothesis that food depletion during winter was the cause of the lemming decline following peak abundance at our study site. Other factors may limit lemming populations and prevent them from reaching densities high enough to exhaust their food resources.     

Is NO the king? Pathophysiological benefit with uncertain clinical impact

NO is the "hero" molecule of the last few decades. It is a ubiquitous and omnipotent radical with both hemodynamic and antiproliferative effects within the cardiovascular system. NO is an important counterregulatory factor for vasoconstrictors and growth promoting substances. Endothelial dysfunction with decreased NO production is related to many cardiovascular disorders, such as coronary artery disease, heart failure and hypertension. Despite the important role of NO within the circulation, there is only limited evidence in the form of large clinical trials that NO delivery can reduce cardiovascular morbidity and mortality. Thus, NO donors are not in the first line therapy in ischemic heart disease, heart failure or arterial hypertension and NO delivery is recommended only in particular clinical situations, when a well established treatment is contraindicated or has an insufficient effect. It is concluded that the insufficient NO production is the principal disorder in endothelial dysfunction, which is related to cardiovascular pathology with deteriorated prognosis, but the impact of therapeutically increased NO bioactivity on the morbidity and mortality is inferior to well established treatment with ACE-inhibitors, AT(1) receptor blockers, beta-blockers, statins and certain antihypertensive drugs. There is little doubt that NO is king in the circulation, but kings seldom decide the battles.     

The impact of type I diabetes on rat liver γ-glutamyltranspeptidase

The impact of type 1 diabetes mellitus on liver -glutamyltranspeptidase, a premalignant marker, was studied. Diabetes was induced in male Sprague Dawley and Fischer 344 rats by administration of Streptozotocin, which produced a stable and moderately severe diabetic state. In liver homogenates, -glutamyltranspeptidase was increased over control levels: 1.2, 8.1 and 13,2 fold in Strague-Dawley rats; 4.8, 58.4 and 84.7 fold in Fischer 344 rats; at 1, 3 and 6 weeks following Streptozotocin treatment. In plasma membranes isolated from the livers of Fischer 344 rats, -glutamyltranspeptidase was increased over control levels: 5.6, 75 and 127 fold at weeks 1, 3 and 6 following Streptozotocin treatment. The relative specific activity of 5-nuleohdase was found to be similar: 9–14, indicating comparable degrees of plasma membrane purity. Plasma glutamate-pyruvate transaminase levels were minimally and similarly affected at all time points indicating lack of association of increasing -glutamyltranspeptidase activity with overt liver damage. Thyroid hormone replacement, with both T₃ (0.6 g/Kg) once a day and T₄ (6.0 g/kg) twice a day for three days elicited a further 30% increment in enzyme activity. Insulin replacement (20–40 units/200 g body weight) twice a day for five days reduced enzyme activity 51% at week 6. This was associated with an increase in -glutamyltranspeptidase in the plasma from 14 fold over control levels in the diabetic state at week 6 to 53 fold ever control levels after insulin replacement at week 6. It is proposed that the diabetes-induced increase in -glutamyltranspeptidase is reduced by an insulin-directed shedding of the enzyme into the plasma.     

Are non-sexual models appropriate for predicting the impact of virus-vectored immunocontraception?

In response to the need to efficiently control mammal pest populations while avoiding unnecessary suffering, applied and theoretical ecologists have recently focused on virus-vectored immunocontraception (VVIC). So far, modellers have only considered a non-sexual approach (models of sexually reproducing populations without explicitly discerning between the sexes), which appears dubious in view of the sex-specificity of VVIC agents. In this paper, we derive and compare predictions of non-sexual and two-sex models of the spread of a VVIC agent in a host population in order to assess the adequacy of non-sexual models in this context. Our results show that predictions of non-sexual and two-sex models generally diverge and that non-sexual models often fail to predict the control impact of VVIC. We thus recommend using two-sex models, especially if the mating system and life history of the target species are known. Our analysis also shows that female-specific viruses generally give better results than male-specific ones, and suggests that virus choice should focus more on its sterilizing power rather than transmission efficiency.     

Brazilian pepper—Its impact on people,animals and the environment

Native to Brazil,Schinus terebinthifolius Raddi, of the family Anacardiaceae, has been commonly cultivated in Florida for over 50 years as a dooryard ornamental. Use of its sprays of showy red fruits for Christmas decoration gave rise to the popular misnomer “Florida holly.” Too late it was found to become a large, spreading tree; aggressive seedlings began springing up near and far. Jungles ofSchinus have crowded out native vegetation over vast areas of Florida and the Bahamas, as in all the islands of Hawaii. When in bloom, the tree is a major source of respiratory difficulty and dermatitis; the fruits, in quantity, intoxicate birds and cause fatal trauma in four-footed animals. The abundant nectar yields a spicy commercial honey and beekeepers are opposed to eradication programs.