Development and validation of sensitive and rapid immunoassays to detect minute amounts of hazelnut in processed food and working surfaces

Hazelnut (Corylus avellana L.) represents one of the most allergenic nuts and it can be found as a hidden allergen in processed food due to cross contamination. Therefore, sensitive and specific analytical techniques are in high demand to be used in allergen risk management plans at food industry. In this study, sandwich ELISA and Lateral Flow Immunoassay (LFIA) to detect hazelnut have been developed based on the determination of Cor a 9, one of the most abundant and allergenic proteins of hazelnut. Results showed that cross-reactivity was only found with walnut and Pecan nut, which was lower than 0.1%. When analyzing food spiked with a hazelnut extract or blended with hazelnut flour, ELISA and LFIA were able to detect 0.1 ppm and 0.5 ppm of hazelnut protein with a recovery from 82 to 110%. ELISA and LFIA could also detect 0.15 and 0.6 ppm of hazelnut protein in baked cookies incurred with ground hazelnut, respectively. Furthermore, LFIA could detect 1.25 μg of hazelnut protein in working surfaces of stainless steel and melamine. The sandwich ELISA was in-house validated, showing acceptable results of precision. Likewise, ELISA and LFIA showed to be robust tests. The combined use of both assays could improve the allergen risk management plans in food industry to monitor the presence of hazelnut traces in raw ingredients, processed food and working surfaces

Pharmacological targeting of the receptor ALK inhibits tumorigenicity and overcomes chemoresistance in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is an extremely aggressive disease characterized by its metastatic potential and chemoresistance. These traits are partially attributable to the highly tumorigenic pancreatic cancer stem cells (PaCSCs). Interestingly, these cells show unique features in order to sustain their identity and functionality, some of them amenable for therapeutic intervention. Screening of phospho-receptor tyrosine kinases revealed that PaCSCs harbored increased activation of anaplastic lymphoma kinase (ALK). We subsequently demonstrated that oncogenic ALK signaling contributes to tumorigenicity in PDAC patient-derived xenografts (PDXs) by promoting stemness through ligand-dependent activation. Indeed, the ALK ligands midkine (MDK) or pleiotrophin (PTN) increased self-renewal, clonogenicity and CSC frequency in several in vitro local and metastatic PDX models. Conversely, treatment with the clinically-approved ALK inhibitors Crizotinib and Ensartinib decreased PaCSC content and functionality in vitro and in vivo, by inducing cell death. Strikingly, ALK inhibitors sensitized chemoresistant PaCSCs to Gemcitabine, as the most used chemotherapeutic agent for PDAC treatment. Consequently, ALK inhibition delayed tumor relapse after chemotherapy in vivo by effectively decreasing the content of PaCSCs. In summary, our results demonstrate that targeting the MDK/PTN-ALK axis with clinically-approved inhibitors impairs in vivo tumorigenicity and chemoresistance in PDAC suggesting a new treatment approach to improve the long-term survival of PDAC patients

Investigaciones de factores asociados: ¿con cuál “desempeño” hacer las comparaciones?

During 2007, Corpoeducación and Luker, Carvajal, Crown and Genesis foundations have developed the research: “Design, pilotage and adjustment of an instrument of associated factors to the quality of the students educative processes”., A conceptual frame was elaborated for; some indicators were built to designinstruments intended for students, teachers, directors and parents; the instruments were piloted in 42 educational institutions of Barranquilla, Bogota, Buenaventura, Cali and Manizales. The analysis demonstrated that itis not possible to affect the performance of the students considering only one aspect, ignoring the others; also that -based on its own responsibilities- each instance decides according to the particularities of its reality and that the different ways to appreciate the performance are all legitimate.Corpoeducación y las fundaciones Luker, Carvajal, Corona y Génesis desarrollaron durante el 2007 la investigación llamada “Diseño, pilotaje y ajuste de un instrumento de factores asociados a la calidad de los procesos educativos de los estudiantes”. Para ello, se elaboró un referente conceptual; se construyeron indicadores para diseñar instrumentos dirigidos a estudiantes, docentes, rectores y padres de familia; se pilotearon los instrumentos en 42 instituciones educativas de Barranquilla, Bogotá, Buenaventura, Cali y Manizales. El análisis mostró que no es posible incidir en el desempeño de los estudiantes mediante la afectación de un aspecto haciendo caso omiso de los demás; que en función de sus responsabilidades, cada instancia decide frente a las particularidades de su realidad y que las distintas formas de apreciar el desempeño son todas legítimas

Temporal variability in the response to thermal stress in the red gorgonian, P. clavata: Insights form common garden experiments

4th Mediterranean Symposium on the Conservation of Coralligenous & other Calcareous Bio-Concretions, 20-21 September 2022, Genoa, Italy.-- 6 pages, 2 figuresRecurrent mass mortality events (MMEs) linked to marine heatwaves (MHWs) have been observed in the Mediterranean Sea affecting thousands of kilometers of coastline. Coralligenous habitats were among the most impacted during these events. Information on how the exposure to recurrent MHWs is affecting the coralligenous is critical to anticipate the consequences of climate change and implement actions to enhance their resilience. Combining field surveys with experiments in controlled conditions allowed to dilucidate the differential responses to thermal stress among species, populations and individuals and to explore the spatial and taxonomic variability response to thermal stress linked to MHWs. Yet, the temporal variability in the response to thermal stress remains to be characterized. Thus, we aim to fill this gap focusing on the temporal variability in the response to thermal stress of the coralligenous key habitat-forming species Paramuricea clavata (Plexauridae). We replicated thermal stress experiments during 3 consecutive years following a common garden setup (control vs. thermal stress) involving the same individuals from the same three populations. Considering different phenotypic responses including the level of tissue necrosis during the time of the experiment and the survival of the individuals, we found that the average percentage of tissue necrosis per population variated greatly across years while the probability of survival was considerably reduced in 2017. During the experiments, several individuals from the 3 populations systematically showed reduced level of tissue necrosis suggesting resistance to thermal stress. Overall our data will contribute to help better inform further conservation strategies of habitat-forming coral species in the Mediterranean SeaPeer reviewe

Identification and characterization of Cardiac Glycosides as senolytic compounds

Compounds with specific cytotoxic activity in senescent cells, or senolytics, support the causal involvement of senescence in aging and offer therapeutic interventions. Here we report the identification of Cardiac Glycosides (CGs) as a family of compounds with senolytic activity. CGs, by targeting the Na+/K+ATPase pump, cause a disbalanced electrochemical gradient within the cell causing depolarization and acidification. Senescent cells present a slightly depolarized plasma membrane and higher concentrations of H+, making them more susceptible to the action of CGs. These vulnerabilities can be exploited for therapeutic purposes as evidenced by the in vivo eradication of tumors xenografted in mice after treatment with the combination of a senogenic and a senolytic drug. The senolytic effect of CGs is also effective in the elimination of senescence-induced lung fibrosis. This experimental approach allows the identification of compounds with senolytic activity that could potentially be used to develop effective treatments against age-related diseases.We thank Matthias Drosten, Alejo Efeyan and Sean Morrison for plasmids. F.T-M. is a postdoctoral fellow from CONACYT (cvu 268632); P.P. is a predoctoral fellow from Xunta de Galicia; M.C. is a "Miguel Servet II" investigator (CPII16/00015). P.P.-R. receives support from a program by the Deputacion de Coruna (BINV-CS/2019). Work in the laboratory of M.C. is funded by grant RTI2018-095818-B-100 (MCIU/AEI/FEDER, UE). P.J.F.-M. is funded by the IMDEA Food Institute, the Ramon Areces Foundation, (CIVP18A3891), and a Ramon y Cajal Award (MICINN) (RYC-2017-22335). M.P.I. is funded by Talento Modalidad-1 Program Grant, Madrid Regional Government (#2018-T1/BIO-11262). F.P. was funded by a Long Term EMBO Fellowship (ALTF-358-2017) and F.H-G. was funded by the PhD4MD Programme of the IRB, Hospital Clinic and IDIBAPS. Work in the laboratory of M.S. was funded by the IRB and by grants from the Spanish Ministry of Economy co-funded by the European Regional Development Fund (ERDF) (SAF2013-48256-R), the European Research Council (ERC-2014-AdG/669622), and "laCaixa" Foundation.S

Intrinsic Order and Disorder in the Bcl-2 Member Harakiri: Insights into Its Proapoptotic Activity

Harakiri is a BH3-only member of the Bcl-2 family that localizes in membranes and induces cell death by binding to prosurvival Bcl-xL and Bcl-2. The cytosolic domain of Harakiri is largely disorder with residual α-helical conformation according to previous structural studies. As these helical structures could play an important role in Harakiri's function, we have used NMR and circular dichroism to fully characterize them at the residue-atomic level. In addition, we report structural studies on a peptide fragment spanning Harakiri's C-terminal hydrophobic sequence, which potentially operates as a transmembrane domain. We initially checked by enzyme immunoassays and NMR that peptides encompassing different lengths of the cytosolic domain are functional as they bind Bcl-xL and Bcl-2. The structural data in water indicate that the α-helical conformation is restricted to a 25-residue segment comprising the BH3 domain. However, structure calculation was precluded because of insufficient NMR restraints. To bypass this problem we used alcohol-water mixture to increase structure population and confirmed by NMR that the conformation in both milieus is equivalent. The resulting three-dimensional structure closely resembles that of peptides encompassing the BH3 domain of BH3-only members in complex with their prosurvival partners, suggesting that preformed structural elements in the disordered protein are central to binding. In contrast, the transmembrane domain forms in micelles a monomeric α-helix with a population close to 100%. Its three-dimensional structure here reported reveals features that explain its function as membrane anchor. Altogether these results are used to propose a tentative structural model of how Harakiri works

Characterization of a Novel Interaction between Bcl-2 Members Diva and Harakiri

Interactions within proteins of the Bcl-2 family are key in the regulation of apoptosis. The death-inducing members control apoptotic mechanisms partly by antagonizing the prosurvival proteins through heterodimer formation. Structural and biophysical studies on these complexes are providing important clues to understand their function. To help improve our knowledge on protein-protein interactions within the Bcl-2 family we have studied the binding between two of its members: mouse Diva and human Harakiri. Diva has been shown to perform both prosurvival and killing activity. In contrast, Harakiri induces cell death by interacting with antiapoptotic Bcl-2 members. Here we show using ELISA and NMR that Diva and Harakiri can interact in vitro. Combining the NMR data with the previously reported three-dimensional structure of Diva we find that Harakiri binds to a specific region in Diva. This interacting surface is equivalent to the known binding area of prosurvival Bcl-2 members from the reported structures of the complexes, suggesting that Diva could function at the structural level similarly to the antiapoptotic proteins of the Bcl-2 family. We illustrate this result by building a structural model of the heterodimer using molecular docking and the NMR data as restraints. Moreover, combining circular dichroism and NMR we also show that Harakiri is largely unstructured with residual (13%) α-helical conformation. This result agrees with intrinsic disorder previously observed in other Bcl-2 members. In addition, Harakiri constructs of different length were studied to identify the region critical for the interaction. Differential affinity for Diva of these constructs suggests that the amino acid sequence flanking the interacting region could play an important role in binding

Factors controlling plankton community production, export flux, and particulate matter stoichiometry in the coastal upwelling system off Peru

Eastern boundary upwelling systems (EBUS) are among the most productive marine ecosystems on Earth. The production of organic material is fueled by upwelling of nutrient-rich deep waters and high incident light at the sea surface. However, biotic and abiotic factors can modify surface production and related biogeochemical processes. Determining these factors is important because EBUS are considered hotspots of climate change, and reliable predictions of their future functioning requires understanding of the mechanisms driving the biogeochemical cycles therein. In this field experiment, we used in situ mesocosms as tools to improve our mechanistic understanding of processes controlling organic matter cycling in the coastal Peruvian upwelling system. Eight mesocosms, each with a volume of ∼55 m3, were deployed for 50 d ∼6 km off Callao (12∘ S) during austral summer 2017, coinciding with a coastal El Niño phase. After mesocosm deployment, we collected subsurface waters at two different locations in the regional oxygen minimum zone (OMZ) and injected these into four mesocosms (mixing ratio ≈1.5 : 1 mesocosm: OMZ water). The focus of this paper is on temporal developments of organic matter production, export, and stoichiometry in the individual mesocosms. The mesocosm phytoplankton communities were initially dominated by diatoms but shifted towards a pronounced dominance of the mixotrophic dinoflagellate (Akashiwo sanguinea) when inorganic nitrogen was exhausted in surface layers. The community shift coincided with a short-term increase in production during the A. sanguinea bloom, which left a pronounced imprint on organic matter C : N : P stoichiometry. However, C, N, and P export fluxes did not increase because A. sanguinea persisted in the water column and did not sink out during the experiment. Accordingly, export fluxes during the study were decoupled from surface production and sustained by the remaining plankton community. Overall, biogeochemical pools and fluxes were surprisingly constant for most of the experiment. We explain this constancy by light limitation through self-shading by phytoplankton and by inorganic nitrogen limitation which constrained phytoplankton growth. Thus, gain and loss processes remained balanced and there were few opportunities for blooms, which represents an event where the system becomes unbalanced. Overall, our mesocosm study revealed some key links between ecological and biogeochemical processes for one of the most economically important regions in the oceans

Host factor PLAC8 is required for pancreas infection by SARS-CoV-2

Although mounting evidence demonstrated that pancreas is infected by SARS-CoV-2 the severity and pathophysiology of pancreatic COVID-19 disease are still unclear. Here we investigated the consequences of SARS-CoV-2 infection of the pancreas and the role of Placenta-associated protein-8 (PLAC8). Our data showed pancreatic damage in patients who died from COVID-19. Notably, circulating pancreatic enzymes stratified patients according to COVID-19 severity and outcome. PLAC8 expression was associated with SARS-CoV-2 infection in postmortem analysis of COVID-19 patients and functional assays demonstrated the requirement of PLAC8 in SARS-CoV-2 pancreatic infection. Full SARS-CoV-2 infectious virus revealed a requirement of PLAC8 for efficient viral infection of pancreatic cell lines. Finally, we observed colocalization of PLAC8 and SARS-CoV-2 in the pancreas of deceased patients. In conclusion, our data confirm the human pancreas as a SARS-CoV-2 target and demonstrate the requirement of PLAC8 for SARS-CoV-2 pancreatic infection thereby opening new target opportunities for COVID-19-associated pancreatic pathogenesis.N

Cytogenetic analysis of three species of Pseudacteon (Diptera, Phoridae) parasitoids of the fire ants using standard and molecular techniques

Pseudacteon flies, parasitoids of worker ants, are being intensively studied as potentially effective agents in the biological control of the invasive pest fire ant genus Solenopsis (Hymenoptera: Formicidae). This is the first attempt to describe the karyotype of P. curvatus Borgmeier, P. nocens Borgmeier and P. tricuspis Borgmeier. The three species possess 2n = 6; chromosomes I and II were metacentric in the three species, but chromosome pair III was subtelocentric in P. curvatus and P. tricuspis, and telocentric in P. nocens. All three species possess a C positive band in chromosome II, lack C positive heterochromatin on chromosome I, and are mostly differentiated with respect to chromosome III. P. curvatus and P. tricuspis possess a C positive band, but at different locations, whereas this band is absent in P. nocens. Heterochromatic bands are neither AT nor GC rich as revealed by fluorescent banding. In situ hybridization with an 18S rDNA probe revealed a signal on chromosome II in a similar location to the C positive band in the three species. The apparent lack of morphologically distinct sex chromosomes is consistent with proposals of environmental sex determination in the genus. Small differences detected in chromosome length and morphology suggests that chromosomes have been highly conserved during the evolutionary radiation of Pseudacteon. Possible mechanisms of karyotype evolution in the three species are suggested