Biosaline agriculture: an agronomic proposal for onion (Allium cepa L.) production.

NOVELTY STATEMENT: The onion crop with brackish irrigation but accompanied by halophytes is productive, so halophytoremediation is an excellent agronomic proposal for areas where there is poor quality water used for irrigation.

Potential of Bacopa monnieri (L.) Wettst and Sesuvium verrucosum Raf. as an agronomic management alternative to recover the productivity of saline soils.

Water scarcity and increasing salinity are the main limiting environmental factors directly affecting the establishment and development of agroecosystems. The objective of this study was to assess the capacity of the halophytes Bacopa monnieri (L.) Wettst and Sesuvium verrucosum Raf., to improve the chemical properties of a saline soil during a 240-day period in the field so as to subsequently examine their potential to associate with Zea mays in the previously desalinated surface. The treatments proposed were [T1 (reference soil sample), T2 (soil + B. monnieri), T3 (soil + S. verrucosum), and T4 (soil + B. monnieri + S. verrucosum)]. The results showed that the association of the species B monnieri and S. verrucosum has the potential to enhance the chemical characteristics of the severely saline and clayey soil, showing ECe reductions of 11.13-7.97 dS/m and pH of 7.84-7.42, as well as increase in soil porosity from 54.71% to 57.23%. It was also found that the association of these plants have a phytodesalination capacity of 1.21 t Na+ ha-1, this served to prepare the conditions for the growth of the Z. mays and generate yields of 8.5 t ha-1.

The regulatory effect of Tau protein on polymerization of MCF7 microtubules in vitro.

Growing evidence continues to point toward the critical role of beta tubulin isotypes in regulating some intracellular functions. Changes that were observed in the microtubules' intrinsic dynamics, the way they interact with some chemotherapeutic agents, or differences on translocation specifications of some molecular motors along microtubules, were associated to their structural uniqueness in terms of beta tubulin isotype distributions. These findings suggest that the effects of microtubule associated proteins (MAPs) may also vary on structurally different microtubules. Among different microtubule associated proteins, Tau proteins, which are known as neuronal MAPs, bind to beta tubulin, stabilize microtubules, and consequently promote their polymerizations. In this study, in a set of well controlled experiments, the direct effect of Tau proteins on the polymerization of two structurally different microtubules, porcine brain and breast cancer (MCF7), were tested and compared. Remarkably, we found that in contrast with the promoted effect of Tau proteins on brain microtubules' polymerization, MCF7 expressed a demoted polymerization while interacting with Tau proteins. This finding can potentially be a novel insight into the mechanism of drug resistance in some breast cancer cells. It has been reported that microtubules show destabilizing behavior in some MCF7 cells with overexpression of Tau protein when treated with a microtubules' stabilizing agent, Taxol. This behavior has been classified by others as drug resistance, but it may instead be potentially caused by a competition between the destabilizing effect of the Tau protein and the stabilizing effect of the drug on MCF7 microtubules. Also, we quantified the polarization coefficient of MCF7 microtubules in the presence and absence of Tau proteins by the electro-orientation method and compared the values. The two significantly different values obtained can possibly be one factor considered to explain the effect of Tau proteins on the polymerization of MCF7 microtubules.

Electrostatic differences: A possible source for the functional differences between MCF7 and brain microtubules.

Recent studies suggested a link between diversity of beta tubulin isotypes in microtubule structures and the regulatory roles that they play not only on microtubules' intrinsic dynamic, but also on the translocation characteristics of some of the molecular motors along microtubules. Remarkably, unlike porcine brain microtubules, MCF7 microtubules are structured from a different beta tubulin distribution. These types of cancer microtubules show a relatively stable and slow dynamic. In addition, the translocation parameters of some molecular motors are distinctly different along MCF7 as compared to those parameters on brain microtubules. It is known that the diversity of beta tubulin isotypes differ predominantly in the specifications and the electric charge of their carboxy-terminal tails. A key question is to identify whether the negative electrostatic charge of tubulin isotypes and, consequently, microtubules, can potentially be considered as one of the sources of functional differences in MCF7 vs. brain microtubules. We tested this possibility experimentally by monitoring the electro-orientation of these two types of microtubules inside a uniform electric field. Through this evaluation, we quantified and compared the average normalized polarization coefficient of MCF7 vs. Porcine brain microtubules. The higher value obtained for the polarization of MCF7 microtubules, which is associated to the higher negative charge of these types of microtubules, is significant as it can further explain the slow intrinsic dynamic that has been recently reported for single MCF7 microtubules in vitro. Furthermore, it can be potentially considered as a factor that can directly impact the translocation parameters of some molecular motors along MCF7 microtubules, by altering the mutual electrostatic interactions between microtubules and molecular motors.

Malestar e ictericia. Hepatitis tóxica por Copalchi / Illness and jaundice. Copalchi toxic hepatitis

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