Lubrication Performance of Sunflower Oil Reinforced with Halloysite Clay Nanotubes (HNT) as Lubricant Additives

This study evaluates the tribological performance of nanolubricants of a vegetable oil (sunflower oil) reinforced with different concentrations of environmentally-friendly nanoparticles of halloysite clay nanotubes (HNTs). Tribological characterization was performed under different conditions to determine its effect on the nanolubricants’ performance and optimal HNT concentration. The tribological performances under low and high contact pressures were analyzed with a block-on-ring tribometer following the ASTM G-077-05 standard procedure. The extreme pressure (EP) properties of the nanolubricants were determined with a T-02 four-ball tribotester according to the ITeE-PIB Polish method for testing lubricants under scuffing conditions. In addition, the lubrication performance of the newly-developed vegetable oil-based nanolubricants was evaluated in an industrial-type application through a tapping torque test. The results indicated that at a low contact pressure 1.5 wt.% HNTs/sunflower oil provided the best tribological behavior by decreasing the coefficient of friction (COF) and wear volume loss by 29 and 70%, respectively. For high contact pressures, 0.05 wt.% HNTs lowered COF and wear by 55% and 56%, respectively. The load-carrying capacity increased by 141% with 0.10 wt.% HNTs compared to the sunflower oil. A high tapping torque efficiency was obtained with HNTs that can prolong tool life in the machining process. Therefore, this study suggests that HNTs/sunflower oil could be used as green lubricants for industrial applications

Infección por VIH asociado a linfoma y herpes zóster: Reporte de caso

La infección por VIH se caracteriza por tres fases: aguda, asintomática y avanzada; esta última caracterizada por inmunodeficiencia severa, lo que expone al paciente a contraer infecciones oportunistas o cáncer. Presentamos un paciente varón de 52 años que acude por dolor en la región retromandibular izquierda, con multiples ampollas de color rojizo, aspecto descamativo, a predominio de dermatomas cervicales C4 - C5 y lumbares L1 - L5, se le realiza examen anatomopatológico del ganglio cervical encontrando hallazgos sugestivos de neoplasia linfoide maligna. Los linfomas no Hodgkin (LNH) surgen de los linfocitos B, linfocitos T y linfocitos NK. Estas neoplasias se desarrollan en los ganglios linfáticos, pero puede ocurrir en cualquier tejido. Los LNH afectan frecuentemente la cabeza y el cuello. La inmunosupresión generada por el VIH produce la reactivación del virus de varicela-zóster y es una condición de susceptibilidad para el desarrollo de linfomas.   Palabras clave: VIH (DeCS), Herpes Zóster (DeCS), Linfoma (DeCS)   DOI: http://dx.doi.org/10.17268/rmt.2021.v16i03.1

El efecto de los agroquimicos sobre las abejas meliferas (Apis mellifera) y su relación con el síndrome del colapso de las colonias

The role of bees in agroecosystems is extremely important because they act as natural pollinating agents of both economically important crops and wild plants; which guarantees the production of food and the conservation of biodiversity. In addition, beekeeping represents one of the sectors that obtain the most economic income from the sale and export of honey. However, this sector has multiple problems in its production system, pests, and diseases that have affected them and has caused declines in the number of colonies and a decrease in honey production. Added to this, in the recent years there has been a spontaneous disappearance of bees,without being able to give a convincing explanation; This phenomenon is known as colony collapse disorder or CCD by its acronym in English. One of the factors that affect and cause the collapse of the colonies is the use of agrochemicals, mainly insecticides of the group of neonicotinoids. These insecticides are derivatives of nicotine and when applied to control crop pests also affect the nervous system of bees, causing them to lose their sense of orientation and unable to return to their colony, which causes their death in the field. Hence the recommendation to control and legislate the use of this type of insecticide in Mexico, as has been done in other countries, to protect bees and thereby ensure the production of food for the benefit of humanity.El papel de las abejas en los agroecosistemas es sumamente importante debido a que actúan como agentes polinizadores naturales tanto de los cultivos de importancia económica como de las plantas silvestres; con lo cual se garantiza la producción de alimentos y la conservación de la biodiversidad. Aparte, la apicultura representa uno de los sectores que obtiene más ingresos económicos por concepto de venta y exportación de miel. Sin embargo, este sector tiene múltiples problemas en su sistema de producción, plagas y enfermedades que los han afectado y ha provocado bajas en el número de colonias y una disminución en la producción de miel. Aunado a esto, en los últimos años se ha presentado una desaparición espontanea de las abejas, sin que se le haya podido dar una explicación convincente; a este fenómeno se le conoce como desorden del colapso de las colonias o CCD por sus siglas en ingles. Uno de los factores que afectan y que provocan el colapso de las colonias son el uso de los agroquímicos, principalmente los insecticidas del grupo de los neonicotinoides. Estos insecticidas son derivados de la nicotina y al ser aplicados para controlar las plagas de los cultivos también afectan al sistema nervioso de las abejas, provocando que pierdan el sentido de orientación y que no puedan regresar a su colonia, lo que provoca su muerte en el campo. De aquí la recomendación de controlar y legislar el uso de este tipo de insecticidas en México, como se ha hecho en otros países, para proteger a las abejas y con ello garantizar la producción de alimentos en beneficio de la humanidad

Sex Hormone Receptor Expression in Craniopharyngiomas and Association with Tumor Aggressiveness Characteristics

Craniopharyngiomas (CPs) are rare tumors of the sellar and suprasellar regions of embryonic origin. The primary treatment for CPs is surgery but it is often unsuccessful. Although CPs are considered benign tumors, they display a relatively high recurrence rate that might compromise quality of life. Previous studies have reported that CPs express sex hormone receptors, including estrogen and progesterone receptors. Here, we systematically analyzed estrogen receptor α (ERα) and progesterone receptor (PR) expression by immunohistochemistry in a well-characterized series of patients with CP (n = 41) and analyzed their potential association with tumor aggressiveness features. A substantial proportion of CPs displayed a marked expression of PR. However, most CPs expressed low levels of ERα. No major association between PR and ERα expression and clinical aggressiveness features was observed in CPs. Additionally, in our series, β-catenin accumulation was not related to tumor recurrence. View Full-TextThis work was supported by grants from the ISCIII-Subdirección General de Evaluación y Fomento de la Investigación co-funded with Fondos FEDER (PI16/00175 to A.S-M. and D.A.C.) and the Sistema Andaluz de Salud (A-0006-2017 and A-0055-2018 to A.S-M, RC-0006-2018 to D.A.C.)

Ultrafast measurements of mode-specific deformation potentials of Bi2_2Te3_3 and Bi2_2Se3_3

Quantifying electron-phonon interactions for the surface states of topological materials can provide key insights into surface-state transport, topological superconductivity, and potentially how to manipulate the surface state using a structural degree of freedom. We perform time-resolved x-ray diffraction (XRD) and angle-resolved photoemission (ARPES) measurements on Bi$_2$Te$_3$ and Bi$_2$Se$_3$, following the excitation of coherent A$_{1g}$ optical phonons. We extract and compare the deformation potentials coupling the surface electronic states to local A$_{1g}$-like displacements in these two materials using the experimentally determined atomic displacements from XRD and electron band shifts from ARPES.We find the coupling in Bi$_2$Te$_3$ and Bi$_2$Se$_3$ to be similar and in general in agreement with expectations from density functional theory. We establish a methodology that quantifies the mode-specific electron-phonon coupling experimentally, allowing detailed comparison to theory. Our results shed light on fundamental processes in topological insulators involving electron-phonon coupling

Borrelia burgdorferi infection induces long-term memory-like responses in macrophages with tissue-wide consequences in the heart

Lyme carditis is an extracutaneous manifestation of Lyme disease characterized by episodes of atrioventricular block of varying degrees and additional, less reported cardiomyopathies. The molecular changes associated with the response to Borrelia burgdorferi over the course of infection are poorly understood. Here, we identify broad transcriptomic and proteomic changes in the heart during infection that reveal a profound down-regulation of mitochondrial components. We also describe the long-term functional modulation of macrophages exposed to live bacteria, characterized by an augmented glycolytic output, increased spirochetal binding and internalization, and reduced inflammatory responses. In vitro, glycolysis inhibition reduces the production of tumor necrosis factor (TNF) by memory macrophages, whereas in vivo, it produces the reversion of the memory phenotype, the recovery of tissue mitochondrial components, and decreased inflammation and spirochetal burdens. These results show that B. burgdorferi induces long-term, memory-like responses in macrophages with tissue-wide consequences that are amenable to be manipulated in vivo.Supported by grants from the Spanish Ministry of Science, Innovation and Universities (MCIU) co-financed with FEDER funds (SAF2015-65327-R and RTI2018-096494-B-100 to JA; BFU2016-76872-R to EB, AGL2017-86757-R to LA, SAF2017-87301-R to MLMC, SAF2015-64111-R to AP, SAF2015-73549-JIN to HR), Instituto de Salud Carlos III (PIE13/0004 to AP), the Basque Government Department of Health (2015111117 to LA), the Basque Foundation for Innovation and Health Research (BIOEF), through the EiTB Maratoia grant BIO15/CA/016/BS to MLMC, the regional Government of Andalusia co-funded by CEC and FEDER funds (Proyectos de Excelencia P12-CTS-2232) and Fundación Domingo Martínez (to AP). LA is supported by the Ramon y Cajal program (RYC-2013-13666). DB, MMR and TMM are recipients of MCIU FPI fellowships. ACG and AP are recipients of fellowships form the Basque Government. APC is a recipient of a fellowship from the University of the Basque Country. We thank the MCIU for the Severo Ochoa Excellence accreditation (SEV-2016-0644), the Basque Department of Industry, Tourism and Trade (Etortek and Elkartek programs), the Innovation Technology Department of the Bizkaia Province and the CIBERehd network. DB and JA are supported by a grant from the Jesús de Gangoiti Barrera Foundation

Severe manifestations of SARS-CoV-2 in children and adolescents: from COVID-19 pneumonia to multisystem inflammatory syndrome: a multicentre study in pediatric intensive care units in Spain

Background Multisystem inflammatory syndrome temporally associated with COVID-19 (MIS-C) has been described as a novel and often severe presentation of SARS-CoV-2 infection in children. We aimed to describe the characteristics of children admitted to Pediatric Intensive Care Units (PICUs) presenting with MIS-C in comparison with those admitted with SARS-CoV-2 infection with other features such as COVID-19 pneumonia. Methods A multicentric prospective national registry including 47 PICUs was carried out. Data from children admitted with confirmed SARS-CoV-2 infection or fulfilling MIS-C criteria (with or without SARS-CoV-2 PCR confirmation) were collected. Clinical, laboratory and therapeutic features between MIS-C and non-MIS-C patients were compared. Results Seventy-four children were recruited. Sixty-one percent met MIS-C definition. MIS-C patients were older than non-MIS-C patients (p = 0.002): 9.4 years (IQR 5.5–11.8) vs 3.4 years (IQR 0.4–9.4). A higher proportion of them had no previous medical history of interest (88.2% vs 51.7%, p = 0.005). Non-MIS-C patients presented more frequently with respiratory distress (60.7% vs 13.3%, p < 0.001). MIS-C patients showed higher prevalence of fever (95.6% vs 64.3%, p < 0.001), diarrhea (66.7% vs 11.5%, p < 0.001), vomits (71.1% vs 23.1%, p = 0.001), fatigue (65.9% vs 36%, p = 0.016), shock (84.4% vs 13.8%, p < 0.001) and cardiac dysfunction (53.3% vs 10.3%, p = 0.001). MIS-C group had a lower lymphocyte count (p < 0.001) and LDH (p = 0.001) but higher neutrophil count (p = 0.045), neutrophil/lymphocyte ratio (p < 0.001), C-reactive protein (p < 0.001) and procalcitonin (p < 0.001). Patients in the MIS-C group were less likely to receive invasive ventilation (13.3% vs 41.4%, p = 0.005) but were more often treated with vasoactive drugs (66.7% vs 24.1%, p < 0.001), corticosteroids (80% vs 44.8%, p = 0.003) and immunoglobulins (51.1% vs 6.9%, p < 0.001). Most patients were discharged from PICU by the end of data collection with a median length of stay of 5 days (IQR 2.5–8 days) in the MIS-C group. Three patients died, none of them belonged to the MIS-C group. Conclusions MIS-C seems to be the most frequent presentation among critically ill children with SARS-CoV-2 infection. MIS-C patients are older and usually healthy. They show a higher prevalence of gastrointestinal symptoms and shock and are more likely to receive vasoactive drugs and immunomodulators and less likely to need mechanical ventilation than non-MIS-C patients

Experiencias de vinculación universitaria desde la formación, la intervención social y la investigación (Complexus 10)

La edición revela experiencias universitarias que analizan y proponen soluciones a problemas sociales mediante la acción colectiva. Muestra la fusión de saberes académicos, experiencias de diversos actores y esfuerzos de la sociedad que se entretejen para construir un mundo más justo y más humano.ITESO, A.C

The Expanded mtDNA Phylogeny of the Franco-Cantabrian Region Upholds the Pre-Neolithic Genetic Substrate of Basques

The European genetic landscape has been shaped by several human migrations occurred since Paleolithic times. The accumulation of archaeological records and the concordance of different lines of genetic evidence during the last two decades have triggered an interesting debate concerning the role of ancient settlers from the Franco-Cantabrian region in the postglacial resettlement of Europe. Among the Franco-Cantabrian populations, Basques are regarded as one of the oldest and more intriguing human groups of Europe. Recent data on complete mitochondrial DNA genomes focused on macrohaplogroup R0 revealed that Basques harbor some autochthonous lineages, suggesting a genetic continuity since pre-Neolithic times. However, excluding haplogroup H, the most representative lineage of macrohaplogroup R0, the majority of maternal lineages of this area remains virtually unexplored, so that further refinement of the mtDNA phylogeny based on analyses at the highest level of resolution is crucial for a better understanding of the European prehistory. We thus explored the maternal ancestry of 548 autochthonous individuals from various Franco-Cantabrian populations and sequenced 76 mitogenomes of the most representative lineages. Interestingly, we identified three mtDNA haplogroups, U5b1f, J1c5c1 and V22, that proved to be representative of Franco-Cantabria, notably of the Basque population. The seclusion and diversity of these female genetic lineages support a local origin in the Franco-Cantabrian area during the Mesolithic of southwestern Europe, ∼10,000 years before present (YBP), with signals of expansions at ∼3,500 YBP. These findings provide robust evidence of a partial genetic continuity between contemporary autochthonous populations from the Franco-Cantabrian region, specifically the Basques, and Paleolithic/Mesolithic hunter-gatherer groups. Furthermore, our results raise the current proportion (≈15%) of the Franco-Cantabrian maternal gene pool with a putative pre-Neolithic origin to ≈35%, further supporting the notion of a predominant Paleolithic genetic substrate in extant European populations