Search

Nitrogen-fixing rhizobial bacteria and leguminous plants have evolved complex signal exchange mechanisms that allow a specific bacterial species to induce its host plant to form invasion structures through which the bacteria can enter the plant root. Once the bacteria have been endocytosed within a host-membrane-bound compartment by root cells, the bacteria differentiate into a new form that can convert atmospheric nitrogen into ammonia. Bacterial differentiation and nitrogen fixation are dependent on the microaerobic environment and other support factors provided by the plant. In return, the plant receives nitrogen from the bacteria, which allows it to grow in the absence of an external nitrogen source. Here, we review recent discoveries about the mutual recognition process that allows the model rhizobial symbiont Sinorhizobium meliloti to invade and differentiate inside its host plant alfalfa (Medicago sativa) and the model host plant barrel medic (Medicago truncatula). [ABSTRACT FROM AUTHOR]

Chagas disease resulting from Trypanosoma cruzi infection leads to a silent, long-lasting chronic neglected tropical disease affecting the poorest and underserved populations around the world. Antiparasitic treatment with benznidazole does not prevent disease progression or death in patients with established cardiac disease. Our consortium is developing a therapeutic vaccine based on the T. cruzi flagellar—derived antigen Tc24-C4 formulated with a Toll-like receptor 4 agonist adjuvant, to complement existing chemotherapy and improve treatment efficacy. Here we demonstrate that therapeutic treatment of acutely infected mice with a reduced dose of benznidazole concurrently with vaccine treatment – also known as "vaccine-linked chemotherapy"—induced a TH17 like immune response, with significantly increased production of antigen specific IL-17A, IL-23 and IL-22, and CD8 + T lymphocytes, as well as significantly increased T. cruzi specific IFNγ-producing CD4 + T lymphocytes. Significantly reduced cardiac inflammation, fibrosis, and parasite burdens and improved survival were achieved by vaccine-linked chemotherapy and individual treatments. Importantly, low dose treatments were comparably efficacious to high dose treatments, demonstrating potential dose sparing effects. We conclude that through induction of TH17 immune responses vaccine-linked chemotherapeutic strategies could bridge the tolerability and efficacy gaps of current drug treatment in Chagasic patients. [ABSTRACT FROM AUTHOR]

Background: Accumulating evidence indicates that Latino children and adolescents are at risk for higher anxiety relative to youth of other ethnicities. However, to date, very little research has been conducted to examine culture specific mechanisms of anxiety in Latino youth.Objective: This study explored whether strict adherence to Latino cultural values emphasizing maintenance of group harmony, familismo and simpatia, in combination with poor awareness and identification of negative emotions predicts increased anxiety among Latino youth.Method: Familismo, simpatia, poor emotion awareness, and anxiety were measured in a mixed clinically anxious (n = 27) and non-clinical (n = 20) sample of 7-13 year-old Latino children. Anxiety was measured through self-report and mother report.Results: Two way interactions between familismo and simpatia, and between poor emotion awareness and simpatia predicted anxiety level. Graphs of the interactions indicated that the combination of high levels of each variable was associated with the highest levels of child-reported anxiety, while high familismo in the context of low simpatia was associated with low anxiety levels per child and parent report. In contrast, low simpatia in the context of poor emotion awareness was associated with low mother-reported child anxiety.Conclusions: Strict adherence to cultural values emphasizing family cohesion and positive interdependent social experiences in combination with poor emotion awareness are linked to anxiety in Latino youth. [ABSTRACT FROM AUTHOR]