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An electronic solid with itinerant carriers and localized magnetic moments represents a paradigmatic strongly correlated system. The electrical transport properties associated with the itinerant carriers, as they scatter off these local moments, has been scrutinized across a number of materials. Here we analyze the transport characteristics associated with ultra-clean PdCrO$_2$ -- a quasi two-dimensional material consisting of alternating layers of itinerant Pd-electrons and Mott-insulating CrO$_2$ layers -- which shows a pronounced regime of $T-$linear resistivity over a wide-range of intermediate temperatures. By contrasting these observations to the transport properties in a closely related material PdCoO$_2$, where the CoO$_2$ layers are band-insulators, we can rule out the traditional electron-phonon interactions as being responsible for this interesting regime. We propose a previously ignored electron-magnetoelastic interaction between the Pd-electrons, the Cr local-moments and an out-of-plane phonon as the main scattering mechanism that leads to the significant enhancement of resistivity and a $T-$linear regime in PdCrO$_2$ at temperatures far in excess of the magnetic ordering temperature. We suggest a number of future experiments to confirm this picture in PdCrO$_2$, as well as other layered metallic/Mott-insulating materials., Comment: 7 pages, 3 figures. Supplementary material: 10 pages, 3 figures

1 p., Introduction:Carbon catabolite repression (CCR) is widespread in bacteria and allows a competitive advantage by establishing priorities in carbon utilization. This enables bacteria to optimize their growth rates in natural environments that provide complex mixtures of nutrients. The regulatory systems that trigger CCR work changing the expression patterns of genes involved in the uptake and/or metabolism of less preferred carbon sources. Such carbon sources often include aromatic compounds, which are widely distributed in nature and are major environmental pollutants. Anaerobic biodegradation of aromatics usually involves the well-known benzoyl-CoA central pathway (bzd genes). The beta-Proteobacterium Azoarcus sp. CIB has been used as model system to study the effector-specific regulation of the bzd genes. We expand previous studies towards the characterization of the first multicomponent regulatory system that controls carbon catabolite repression of the bzd genes in bacteria., Objectives:To unravel the role of AccT protein into the multicomponent regulatory system that mediates bzd carbon catabolite repression by some organic acids, e.g., succinate, in Azoarcus sp. CIB., Methods:Gene expression studies were performed by qRT-PCR and β-galactosidase assays of PN::lacZ fusions, in the wild-type CIB strain and in accS, accR and accT null mutants, as well as in recombinant E. coli cells expressing reporter fusions. Biochemical assays were carried out to characterize the AccT protein, including protein-ligand interaction techniques, such us: differential scanning fluorimetry, isothermal titration calorimetry and circular dichroism., Conclusion:The accSRT cluster is likely to encode a new three-component regulatory system that senses and responds to changes in extracellular (e.g., organic acids) and intracellular (e.g., redox state) signals in different β-Proteobacteria., Centro de Investigaciones Biológicas Margarita Salas – CSIC, Madrid, España.Ref. Proyecto: BIO2016- 79736-R

IL-17D is a cytokine that belongs to the IL-17 family and is conserved in vertebrates and invertebrates. In contrast to IL-17A and IL-17F, which are expressed in Th17 cells, IL-17D is expressed broadly in nonimmune cells. IL-17D can promote immune responses to cancer and viruses in part by inducing chemokines and recruiting innate immune cells such as NK cells. Although bacterial infection can induce IL-17D in fish and invertebrates, the role of mammalian IL-17D in antibacterial immunity has not been established. To determine whether IL-17D has a role in mediating host defense against bacterial infections, we studied i.p. infection by group A Streptococcus (GAS) in wild-type (WT) and Il17d -/- mice. Compared with WT animals, mice deficient in IL-17D experienced decreased survival, had greater weight loss, and showed increased bacterial burden in the kidney and peritoneal cavity following GAS challenge. In WT animals, IL-17D transcript was induced by GAS infection and correlated to increased levels of chemokine CCL2 and greater neutrophil recruitment. Of note, GAS-mediated IL-17D induction in nonimmune cells required live bacteria, suggesting that processes beyond recognition of pathogen-associated molecular patterns were required for IL-17D induction. Based on our results, we propose a model in which nonimmune cells can discriminate between nonviable and viable GAS cells, responding only to the latter by inducing IL-17D.

Trichomonas vaginalis is a sexually transmitted, eukaryotic parasite that causes trichomoniasis, the most common nonviral, sexually transmitted disease in the USA and worldwide. Little is known about the molecular mechanisms involved in the host immune response to this widespread parasite. Here we report that T. vaginalis induces NLRP3 inflammasome activation in human macrophages, leading to caspase-1 activation and the processing of pro-IL-1β to the mature and bioactive form of the cytokine. Using inhibitor-based approaches, we show that NLRP3 activation by T. vaginalis involves host cell detection of extracellular ATP via P2X7 receptors and potassium efflux. In addition, our data reveal that T. vaginalis inflammasome activation induces macrophage inflammatory cell death by pyroptosis, known to occur via caspase-1 cleavage of the gasdermin D protein, which assembles to form pores in the host cell membrane. We found that T. vaginalis-induced cytolysis of macrophages is attenuated in gasdermin D knockout cells. Lastly, in a murine challenge model, we detected IL-1β production in vaginal fluids in response to T. vaginalis infection in vivo. Together, our findings mechanistically dissect how T. vaginalis contributes to the production of the proinflammatory IL-1β cytokine and uncover pyroptosis as a mechanism by which the parasite can trigger host macrophage cell death.

La mosca suramericana de la fruta Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) es una plaga cuarentenaria de la feijoa. Frutas infestadas artificialmente se sometieron al tratamiento "t 107-a" (1,1° C durante 15 dias) exigido por USDA- APHIS para su exportacion y se compararon con frutos almacenados a temperatura ambiente. Cada fruto se infesto con cuatro larvas de tercer instar, en dos tratamientos con-50 repeticiones. Se evaluo diariamente la longitud, el volumen corporal, el comportamiento. la mortalidad y cambios de coloraciòn de las larvas, en una muestra de tres frutos, El primer comportamiento observable de las larvas bajo tratamiento cuarentenario fue el intento de abandonar el fruto. No se observo ninguna variaciòn en la longitud o el volumen corporal de las larvas bajo frio. En el control a temperatura ambiente, las larvas aumentaron de volumen hasta la muda a pupa. El tratamiento en frio modifico el desarrollo larval y la muda larva-pupa. El 100% de las larvas murio ocho dias despues de estar sometidas al tratamiento de frio. La mayoria de las larvas murieron en un estado intermedio de la muda y presentaron una coloracion oscura o "muda parcial". Bajo el tratamiento cuarentenario el daño a la pulpa no supero el 24%, mientras en el testigo alcanzo el 74%. Este es el primer tratamiento cuarentenario probado para esta plaga en feijoas en Colombia y mostro control total. El cumplimiento de los requisitos cuarentenarios de USDA-APHIS abren el mercado internacional para exportadores colombianos de feijoa. The South American fruit fly Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) is a quarantine pest of pineapple guava. Artificially infested fruits were subjected to cold treatment "t 107a" (1.1° C for 15 d), required by USDA-APHIS for exportation and were compared to control fruits maintained at room temperature. Four third-instar larvae were infested per individual fruit in two treatments with 50 replicates. Body length, volume, behavior, mortality and color changes of the larvae were recorded daily in a sample of three fruits. The first behavioral change observed in larvae under cold quarantine treatment was an attempt to abandon the fruits. No variation in body length or volume was observed under the cold quarantine treatment. In the untreated control, larvae increased body volume up to the final molt to pupa. The cold quarantine treatment affected larval development and the larva-pupa molt. All larvae died on the eighth day of cold treatment. Most larvae died while molting to pupa and exhibited a dark coloration or "partial molt". Under the cold quarantine treatment, damage to fruits did not exceed 24% where as in the untreated control it reached 74%. This is the first cold quarantine treatment tested for this pest of pineapple guavas in Colombia and it provided total control. Compliance with the quarantine requirements of USDA-APHIS opens the international market for Colombian exporters of pineapple guava.

Objetivo: Descripción de una técnica sencilla de gastrostomía quirúrgica que cumple criterios de cirugía mínimamente invasiva y presentación de los resultados obtenidos con la misma, comparándolos con los de otras gastrostomías quirúrgicas así como con los de técnicas percutáneas. Ámbito: Pacientes procedentes de diversos Servicios del Hospital Universitario Miguel Servet de Zaragoza, en régimen de internamiento o ambulatorio, controlados por la Unidad de Nutrición Hospitalaria y con indicación de gastrostomía de alimentación. Pacientes y métodos: Estudio prospectivo que incluye los quince primeros pacientes en los que de forma sucesiva se ha realizado una técnica de gastrostomía quirúrgica mínimamente invasiva desde 1 de enero de 2001 a 30 de junio de 2002 y en los que no habría sido posible la realización de algún tipo de gastrostomía percutánea por diversas causas. La técnica se realizó en quirófano, bajo anestesia local utilizando una sonda de gastrostomía Flexiflo 20 F y con profilaxis antibiótica (amoxicilina-ácido clavulánico: 2 g i.v. preop.). Los pacientes fueron evaluados a los 10, 30 y 60 días de forma ambulatoria por la Unidad de Nutrición y Cirugía. Resultados: La realización del procedimiento pudo concluirse con éxito en todos los casos. El tiempo medio de duración del procedimiento fue de 45 minutos. En 5 casos el procedimiento se realizó de forma ambulatoria. La funcionalidad del dispositivo fue del 100%, siendo efectiva a partir del 10º día posoperatorio. Morbilidad: 6,6%. Mortalidad a 60 días: 0%. Conclusiones: Se trata de un procedimiento que resulta seguro, sencillo, económico, realizable de forma ambulatoria, y por tanto, cumpliendo criterios de mínima invasión, constituyendo una técnica complementaria o alternativa a las técnicas percutáneas, en casos seleccionados o de imposibilidad, fracaso o contraindicación de las mismas.

Background Treatment with angiotensin-converting-enzyme (ACE) inhibitors reduces the rate of cardiovascular events among patients with left-ventricular dysfunction and those at high risk of such events. We assessed whether the ACE inhibitor perindopril reduced cardiovascular risk in a low-risk population with stable coronary heart disease and no apparent heart failure. Methods We recruited patients from October, 1997, to June, 2000. 13655 patients were registered with previous myocardial infarction (64%), angiographic evidence of coronary artery disease (61%), coronary revascularisation (55%), or a positive stress test only (5%). After a run-in period of 4 weeks, in which all patients received perindopril, 12218 patients were randomly assigned perindopril 8 mg once daily (n=6110), or matching placebo (n=6108). The mean follow-up was 4.2 years, and the primary endpoint was cardiovascular death, myocardial infarction, or cardiac arrest. Analysis was by intention to treat. Findings Mean age of patients was 60 years (SD 9), 85% were male, 92% were taking platelet inhibitors, 62% beta blockers, and 58% lipid-lowering therapy. 603 (10%) placebo and 488 (8%) perindopril patients experienced the primary endpoint, which yields a 20% relative risk reduction (95% CI 9-29, p=0.0003) with perindopril. These benefits were consistent in all predefined subgroups and secondary endpoints. Perindopril was well tolerated. Interpretation Among patients with stable coronary heart disease without apparent heart failure, perindopril can significantly improve outcome. About 50 patients need to be treated for a period of 4 years to prevent one major cardiovascular event. Treatment with perindopril, on top of other preventive medications, should be considered in all patients with coronary heart disease.