Are isomeric alkenes used in species recognition among neo-tropical stingless bees (Melipona spp)

The majority of our understanding of the role of cuticular hydrocarbons (CHC) in recognition is based largely on temperate ant species and honey bees. The stingless bees remain relatively poorly studied, despite being the largest group of eusocial bees, comprising more than 400 species in some 60 genera. The Meliponini and Apini diverged between 80-130 Myr B.P. so the evolutionary trajectories that shaped the chemical communication systems in ants, honeybees and stingless bees may be very different. Therefore, the main aim of this study was to study if a unique species CHC signal existed in Neotropical stingless bees, as shown for many temperate species, and if so what compounds are involved. This was achieved by collecting CHC data from 24 colonies belonging to six species of Melipona from North-eastern Brazil and comparing this new data with all previously published CHC studies on Melipona. We found that each of the eleven Melipona species studied so far each produced a unique species CHC signal based around their alkene isomer production. A remarkable number of alkene isomers, up to 25 in M. asilvai, indicated the diversification of alkene positional isomers among the stingless bees. The only other group to have really diversified in alkene isomer production are the primitively eusocial Bumblebees (Bombus spp), which are the sister group of the stingless bees. Furthermore, among the eleven Neotropical Melipona species we could detect no effect of the environment on the proportion of alkane production as has been suggested for some other species

The hidden power of glycine: A small amino acid with huge potential for piezoelectric and piezo-triboelectric nanogenerators

Glycine is the smallest nonessential amino acid in humans and animals, a basic building block with a crucial role on several physiological events. Despite its simplicity, glycine presents three polymorphs – α, β, and γ- with distinct functional properties. While α-glycine is widely used in pharmaceuticals, β- and γ-glycine have found a place in energy harvesting due to their non-centrosymmetric structure and therefore notable piezoelectricity. β-glycine polymorph shows remarkable out-of-plane piezoelectricity (d16 = 178 pm.V−1), comparable to traditional piezoceramics like barium titanate or lead zirconate, whereas γ-glycine demonstrates superior in-plane piezoelectricity (d33 = 10.4 pm.V−1) comparable to biological materials (0.1–10 pm.V−1). Advances in polymorph synthesis and stabilization enabled the fabrication of glycine-based piezoelectric (PENGs) and piezo-triboelectric nanogenerators (PTENGs) with favourable features such as enhanced flexibility, integrability, and electromechanical coupling. In this review, we delineate glycine polymorphism, relative stability, and crystallization methods, with a special focus on strategies to stabilize specific polymorphs in view of enhancing its piezoelectric activity. Furthermore, the interaction of glycine with hydrophilic polymers is explored to develop biodegradable nanogenerators. The development of glycine-based PENGs and PTENGs is presented, with detailed examination of the piezoelectric and triboelectric mechanisms illustrating the beneficial effects of incorporating glycine. These approaches bring the performance of organic-based PTENGs closer to ceramic-based nanogenerators. Emergent applications encompassing sensors for physiological processes and electromechanical energy conversion devices such as ultrasound-induced drug delivery and electrotherapy are reviewed along their performance in vitro and in vivo. Finally, we discuss the advantages,limitations, and future progresses forthese devices. Overall, this review provides a comprehensive overview of glycine research, offering a solid foundation to further its utilization in the field of green energy

Transcription of toll-like receptors 2, 3, 4 and 9, FoxP3 and Th17 cytokines in a susceptible experimental model of canine Leishmania infantum infection

Canine leishmaniosis (CanL) due to Leishmania infantum is a chronic zoonotic systemic disease resulting from complex interactions between protozoa and the canine immune system. Toll-like receptors (TLRs) are essential components of the innate immune system and facilitate the early detection of many infections. However, the role of TLRs in CanL remains unknown and information describing TLR transcription during infection is extremely scarce. The aim of this research project was to investigate the impact of L. infantum infection on canine TLR transcription using a susceptible model. The objectives of this study were to evaluate transcription of TLRs 2, 3, 4 and 9 by means of quantitative reverse transcription polymerase chain reaction (qRT-PCR) in skin, spleen, lymph node and liver in the presence or absence of experimental L. infantum infection in Beagle dogs. These findings were compared with clinical and serological data, parasite densities in infected tissues and transcription of IL-17, IL-22 and FoxP3 in different tissues in non-infected dogs (n = 10), and at six months (n = 24) and 15 months (n = 7) post infection. Results revealed significant down regulation of transcription with disease progression in lymph node samples for TLR3, TLR4, TLR9, IL-17, IL-22 and FoxP3. In spleen samples, significant down regulation of transcription was seen in TLR4 and IL-22 when both infected groups were compared with controls. In liver samples, down regulation of transcription was evident with disease progression for IL-22. In the skin, upregulation was seen only for TLR9 and FoxP3 in the early stages of infection. Subtle changes or down regulation in TLR transcription, Th17 cytokines and FoxP3 are indicative of the silent establishment of infection that Leishmania is renowned for. These observations provide new insights about TLR transcription, Th17 cytokines and Foxp3 in the liver, spleen, lymph node and skin in CanL and highlight possible markers of disease susceptibility in this model

Citizen science for observing and understanding the Earth

Citizen Science, or the participation of non-professional scientists in a scientific project, has a long history—in many ways, the modern scientific revolution is thanks to the effort of citizen scientists. Like science itself, citizen science is influenced by technological and societal advances, such as the rapid increase in levels of education during the latter part of the twentieth century, or the very recent growth of the bidirectional social web (Web 2.0), cloud services and smartphones. These transitions have ushered in, over the past decade, a rapid growth in the involvement of many millions of people in data collection and analysis of information as part of scientific projects. This chapter provides an overview of the field of citizen science and its contribution to the observation of the Earth, often not through remote sensing but a much closer relationship with the local environment. The chapter suggests that, together with remote Earth Observations, citizen science can play a critical role in understanding and addressing local and global challenges

Ly6Chi monocyte recruitment is responsible for Th2 associated host-protective macrophage accumulation in liver inflammation due to schistosomiasis

Accumulation of M2 macrophages in the liver, within the context of a strong Th2 response, is a hallmark of infection with the parasitic helminth, Schistosoma mansoni, but the origin of these cells is unclear. To explore this, we examined the relatedness of macrophages to monocytes in this setting. Our data show that both monocyte-derived and resident macrophages are engaged in the response to infection. Infection caused CCR2-dependent increases in numbers of Ly6Chi monocytes in blood and liver and of CX3CR1+ macrophages in diseased liver. Ly6Chi monocytes recovered from liver had the potential to differentiate into macrophages when cultured with M-CSF. Using pulse chase BrdU labeling, we found that most hepatic macrophages in infected mice arose from monocytes. Consistent with this, deletion of monocytes led to the loss of a subpopulation of hepatic CD11chi macrophages that was present in infected but not naïve mice. This was accompanied by a reduction in the size of egg-associated granulomas and significantly exacerbated disease. In addition to the involvement of monocytes and monocyte-derived macrophages in hepatic inflammation due to infection, we observed increased incorporation of BrdU and expression of Ki67 and MHC II in resident macrophages, indicating that these cells are participating in the response. Expression of both M2 and M1 marker genes was increased in liver from infected vs. naive mice. The M2 fingerprint in the liver was not accounted for by a single cell type, but rather reflected expression of M2 genes by various cells including macrophages, neutrophils, eosinophils and monocytes. Our data point to monocyte recruitment as the dominant process for increasing macrophage cell numbers in the liver during schistosomiasis

Regulation of immunity during visceral Leishmania infection

Unicellular eukaryotes of the genus Leishmania are collectively responsible for a heterogeneous group of diseases known as leishmaniasis. The visceral form of leishmaniasis, caused by L. donovani or L. infantum, is a devastating condition, claiming 20,000 to 40,000 lives annually, with particular incidence in some of the poorest regions of the world. Immunity to Leishmania depends on the development of protective type I immune responses capable of activating infected phagocytes to kill intracellular amastigotes. However, despite the induction of protective responses, disease progresses due to a multitude of factors that impede an optimal response. These include the action of suppressive cytokines, exhaustion of specific T cells, loss of lymphoid tissue architecture and a defective humoral response. We will review how these responses are orchestrated during the course of infection, including both early and chronic stages, focusing on the spleen and the liver, which are the main target organs of visceral Leishmania in the host. A comprehensive understanding of the immune events that occur during visceral Leishmania infection is crucial for the implementation of immunotherapeutic approaches that complement the current anti-Leishmania chemotherapy and the development of effective vaccines to prevent disease.The research leading to these results has received funding from the European Community’s Seventh Framework Programme under grant agreement No.602773 (Project KINDRED). VR is supported by a post-doctoral fellowship granted by the KINDReD consortium. RS thanks the Foundation for Science and Technology (FCT) for an Investigator Grant (IF/00021/2014). This work was supported by grants to JE from ANR (LEISH-APO, France), Partenariat Hubert Curien (PHC) (program Volubilis, MA/11/262). JE acknowledges the support of the Canada Research Chair Program