116,184 research outputs found

    Application of lactic acid bacteria for the biopreservation of meat products: A systematic review

    Get PDF
    .The increasing concern of consumers about food quality and safety and their rejection of chemical additives has promoted the breakthrough of the biopreservation field and the development of studies on the use of beneficial bacteria and their metabolites as potential natural antimicrobials for shelf life extension and enhanced food safety. Control of foodborne pathogens in meat and meat products represents a serious challenge for the food industry which can be addressed through the intelligent use of bio-compounds or biopreservatives. This article aims to systematically review the available knowledge about biological strategies based on the use of lactic acid bacteria to control the proliferation of undesirable microorganisms in different meat products. The outcome of the literature search evidenced the potential of several strains of lactic acid bacteria and their purified or semi-purified antimicrobial metabolites as biopreservatives in meat products for achieving longer shelf life or inhibiting spoilage and pathogenic bacteria, especially when combined with other technologies to achieve a synergistic effect.S

    Bioinformatic characterization of a triacylglycerol lipase produced by Aspergillus flavus isolated from the decaying seed of Cucumeropsis mannii

    Get PDF
    Lipases are enzymes of industrial importance responsible for the hydrolysis of ester bonds of triglycerides. A lipolytic fungus was isolated and subsequently identified based on the ITS sequence analysis as putative Aspergillus flavus with accession number LC424503. The gene coding for extracellular triacylglycerol lipase was isolated from Aspergillus flavus species, sequenced, and characterised using bioinformatics tools. An open reading frame of 420 amino acid sequence was obtained and designated as Aspergillus flavus lipase (AFL) sequence. Alignment of the amino acid sequence with other lipases revealed the presence GHSLG sequence which is the lipase consensus sequence Gly-X1-Ser-X2-Gly indicating that it a classical lipase. A catalytic active site lid domain composed of TYITDTIIDLS amino acids sequence was also revealed. This lid protects the active site, control the catalytic activity and substrate selectivity in lipases. The 3-Dimensional structural model shared 34.08% sequence identity with a lipase from Yarrowia lipolytica covering 272 amino acid residues of the template model. A search of the lipase engineering database using AFL sequence revealed that it belongs to the class GX-lipase, superfamily abH23 and homologous family abH23.02, molecular weight and isoelectric point values of 46.95鈥塊Da and 5.7, respectively. N-glycosylation sites were predicted at residues 164, 236 and 333, with potentials of 0.7250, 0.7037 and 0.7048, respectively. O-glycosylation sites were predicted at residues 355, 358, 360 and 366. A signal sequence of 37 amino acids was revealed at the N-terminal of the polypeptide. This is a short peptide sequence that marks a protein for transport across the cell membrane and indicates that AFL is an extracellular lipase. The findings on the structural and molecular properties of Aspergillus flavus lipase in this work will be crucial in future studies aiming at engineering the enzyme for biotechnology applications

    Uso de las histonas circulantes y sus modificaciones post-traduccionales como biomarcadores en sepsis y shock s茅ptico

    Get PDF
    La sepsis es una afecci贸n potencialmente mortal causada por una respuesta anormal del hu茅sped a una infecci贸n, produciendo respuestas fisiol贸gicas alteradas que da帽an los propios tejidos del paciente y pueden provocar disfunci贸n org谩nica e incluso la muerte. Asimismo, algunos pacientes s茅pticos progresan a shock s茅ptico, caracterizado por alteraciones circulatorias, celulares y metab贸licas sustanciales que aumentan el riesgo de mortalidad. A pesar de que la sepsis se caracteriza por un mal funcionamiento del sistema inmunol贸gico, lo que a su vez conduce a una respuesta inmune alterada e inmunosupresi贸n, la alta complejidad de la fisiopatolog铆a de la sepsis requiere una mayor investigaci贸n para comprender las respuestas inmunes que ocurren durante la sepsis. Asimismo, las histonas extracelulares circulantes han ganado relevancia como mediadores citot贸xicos en la sepsis, ya que act煤an como patrones moleculares asociados a da帽o, que inducen estr茅s oxidativo y activan el inflamasoma NLRP3. Estos mecanismos median la activaci贸n de la piroptosis, un mecanismo de muerte celular programada que produce inflamaci贸n mediante la expresi贸n de IL-18, IL-1尾 and IL-1伪. Sin embargo, a pesar de la evidencia de activaci贸n del inflamasoma en las c茅lulas inmunes durante la sepsis, se desconoce si las histonas extracelulares son capaces de activar los inflamasomas endoteliales y sus consecuencias. En este trabajo destacamos el papel previamente desconocido de las histonas extracelulares, mediando la activaci贸n del inflamasoma NLRP3 y la piroptosis en las c茅lulas endoteliales, contribuyendo a la disfunci贸n endotelial y la desregulaci贸n de la respuesta inmune mediada por el endotelio. Asimismo, tambi茅n demostramos c贸mo la acetilaci贸n de histonas disminuye la activaci贸n de la piroptosis. Adem谩s, demostramos que la piroptosis se produce en pacientes con shock s茅ptico y los niveles de histonas circulantes se correlacionan con la expresi贸n de citoquinas proinflamatorias y citoquinas piropt贸ticas, la liberaci贸n de factores de adhesi贸n endotelial y la gravedad de la enfermedad. Proponemos la piroptosis mediada por histonas como un nuevo objetivo para desarrollar intervenciones cl铆nicas. De manera similar, hemos analizado las respuestas inmunorelacionadas que ocurren durante las primeras etapas de la sepsis con el objetivo de proporcionar nuevos datos comparando las cantidades de citoquinas, inmunomoduladores y otros mediadores endoteliales en pacientes cr铆ticamente enfermos no s茅pticos, s茅pticos y de shock s茅ptico. Nuestro enfoque ayudar谩 a caracterizar r谩pidamente las respuestas inmunes alteradas en pacientes s茅pticos y de shock s茅ptico ingresados en la Unidad de Cuidados Intensivos. Finalmente analizamos el papel de la metilaci贸n del ADN en el control del sistema inmune s茅ptico. Nuestros resultados demostraron el papel central de la metilaci贸n del ADN modulando la respuesta molecular en los pacientes de shock s茅ptico y contribuyendo a la inmunosupresi贸n, a trav茅s de la alteraci贸n de los patrones de metilaci贸n de los promotores de IL-10 y TREM-2.Sepsis is a life-threatening condition caused by an abnormal host response to an infection that produce altered physiological responses which damages own tissues of the patient and can result in organ dysfunction and in some cases death. Likewise, a subset of septic patients progresses to septic shock, characterized by substantial circulatory, cellular and metabolic abnormalities, which substantially increase the risk of mortality. Sepsis is characterized by a malfunction of the immune system and it can lead to an altered immune response and immunosuppression. Moreover, the high complexity of the pathophysiology of sepsis requires of further investigation to characterize the immune responses in sepsis and septic shock. Likewise, circulating extracellular histones have gained relevance as cytotoxic mediators in sepsis pathophysiology, since they act as damage-associated molecular patterns, which induce oxidative stress and activate NLRP3 inflammasome. Subsequently, inflammasome mediates pyroptosis activation, a programmed cell death mechanism that produces inflammation through the release of IL-18, IL-1尾 and IL-1伪. However, despite inflammasome activation may occur in immune cells during sepsis, it is unknown if this process also takes place in endothelial cells and particularly whether extracellular histones are capable of activating endothelial inflammasomes and their consequences. In this work we highlight a previously unknown role for extracellular histones, that mediates the activation of NLRP3 inflammasome and pyroptosis in endothelial cells by contributing to endothelial dysfunction and the dysregulation of the immune response mediated by endothelium. Likewise, we demonstrated how histone acetylation decreases pyroptosis activation. Furthermore, we show how pyroptosis occurs in septic shock patients and how circulating histone levels correlate with the expression of pro-inflammatory and pyroptotic cytokines, the release of endothelial adhesion factors and septic shock severity. We propose histone-mediated pyroptosis as a new target to develop clinical interventions. Similarly, we have analyzed the immune-related responses occurring during the early stages of sepsis with the aim of providing new data by comparing the amounts of cytokines, immune modulators and other endothelial mediators in critically-ill non-septic patients, septic and septic shock patients. Our approach will help to rapidly characterize the altered immune responses in septic and septic shock patients admitted in the Intensive Care Unit. Finally, we also analyzed the role of DNA methylation in the control of septic immune system. Our results demonstrated the central role of DNA methylation modulating the molecular response in septic shock patients and contributing to immunosuppression, through the alteration of DNA methylation patterns of IL-10 and TREM2 promoters

    Participaci贸n de los astrocitos del complejo basolateral de la am铆gdala en diferentes etapas de la formaci贸n de la memoria de miedo contextual

    Get PDF
    50 h.; figuras; ils.. Contiene Referencia Bibliogr谩fica.El objetivo general de este trabajo consiste en indagar sobre la participaci贸n de los astrocitos del C-BLA en las distintas etapas de formaci贸n de la memoria de miedo contextual. Objetivos espec铆ficos: 1) Evaluar los efectos de la inhibici贸n farmacol贸gica de los astrocitos del C-BLA durante la fase de adquisici贸n (administraci贸n de fluorocitrato antes del condicionamiento). 2) Evaluar los efectos de la inhibici贸n farmacol贸gica de los astrocitos del C-BLA durante la fase de consolidaci贸n (administraci贸n de fluorocitrato luego del condicionamiento). 3) Evaluar los efectos de la inhibici贸n farmacol贸gica de los astrocitos del C-BLA durante la fase de evocaci贸n (administraci贸n de fluorocitrato antes del test de recuerdo). 4) Evaluar los efectos de la inhibici贸n farmacol贸gica de los astrocitos del C-BLA durante la fase de reconsolidaci贸n (administraci贸n de fluorocitrato luego de la evocaci贸n de la memoria) Hip贸tesis: La inhibici贸n farmacol贸gica de astrocitos del C-BLA en alguna/s de las distintas fases de la memoria de miedo induce un d茅ficit mn茅sico, indicando la importancia de los astrocitos del C-BLA en dicho proceso. Se espera que en aquellas fases en las que la participaci贸n de los astrocitos sea cr铆tica, los animales que sean infundidos con el inhibidor astroc铆tico muestren un d茅ficit en la performance cognitiva, operacionalizada como una disminuci贸n en la respuesta de congelamiento frente al est铆mulo incondicionado.Fil: Riva Gargiulo, Melisa. Universidad Nacional de C贸rdoba. Facultad de Ciencias Exactas, F铆sicas y Naturales; Argentina.Fil: Riva Gargiulo, Melisa. Universidad Nacional de C贸rdoba. Facultad de Ciencias Qu铆micas. Departamento de Farmacolog铆a; Argentina.Fil: Riva Gargiulo, Melisa. Consejo Nacional de Investigaciones Cient铆ficas y T茅cnicas. Instituto de Farmacolog铆a Experimental de C贸rdoba; Argentina

    Characterising within-hospital SARS-CoV-2 transmission events using epidemiological and viral genomic data across two pandemic waves

    Get PDF
    Hospital outbreaks of COVID19 result in considerable mortality and disruption to healthcare services and yet little is known about transmission within this setting. We characterise within hospital transmission by combining viral genomic and epidemiological data using Bayesian modelling amongst 2181 patients and healthcare workers from a large UK NHS Trust. Transmission events were compared between Wave 1 (1st March to 25th July 2020) and Wave 2 (30th November 2020 to 24th January 2021). We show that staff-to-staff transmissions reduced from 31.6% to 12.9% of all infections. Patient-to-patient transmissions increased from 27.1% to 52.1%. 40%-50% of hospital-onset patient cases resulted in onward transmission compared to 4% of community-acquired cases. Control measures introduced during the pandemic likely reduced transmissions between healthcare workers but were insufficient to prevent increasing numbers of patient-to-patient transmissions. As hospital-acquired cases drive most onward transmission, earlier identification of nosocomial cases will be required to break hospital transmission chains

    Genome-wide identification of the genetic basis of amyotrophic lateral sclerosis

    Get PDF
    Amyotrophic lateral sclerosis (ALS) is a complex disease that leads to motor neuron death. Despite heritability estimates of 52%, genome-wide association studies (GWASs) have discovered relatively few loci. We developed a machine learning approach called RefMap, which integrates functional genomics with GWAS summary statistics for gene discovery. With transcriptomic and epigenetic profiling of motor neurons derived from induced pluripotent stem cells (iPSCs), RefMap identified 690 ALS-associated genes that represent a 5-fold increase in recovered heritability. Extensive conservation, transcriptome, network, and rare variant analyses demonstrated the functional significance of candidate genes in healthy and diseased motor neurons and brain tissues. Genetic convergence between common and rare variation highlighted KANK1 as a new ALS gene. Reproducing KANK1 patient mutations in human neurons led to neurotoxicity and demonstrated that TDP-43 mislocalization, a hallmark pathology of ALS, is downstream of axonal dysfunction. RefMap can be readily applied to other complex diseases

    Facile cellulase immobilisation on bioinspired silica

    Get PDF
    Cellulases are enzymes with great potential for converting biomass to biofuels for sustainable energy. However, their commercial use is limited by their costs and low reusability. Therefore, the scientific and industrial sectors are focusing on finding better strategies to reuse enzymes and improve their performance. In this work, cellulase from Aspergillus niger was immobilised through in situ entrapment and adsorption on bio-inspired silica (BIS) supports. To the best of our knowledge, this green effect strategy has never been applied for cellulase into BIS. In situ entrapment was performed during support synthesis, applying a one-pot approach at mild conditions (room temperature, pH 7, and water solvent), while adsorption was performed after support formation. The loading efficiency was investigated on different immobilisation systems by Bradford assay and FTIR. Bovine serum albumin (BSA) was chosen as a control to optimize cellulase loading. The residual activity of cellulase was analysed by the dinitro salicylic acid (DNS) method. Activity of 90% was observed for the entrapped enzyme, while activity of ~55% was observed for the adsorbed enzyme. Moreover, the supported enzyme systems were recycled five times to evaluate their reuse potential. The thermal and pH stability tests suggested that both entrapment and adsorption strategies can increase enzyme activity. The results highlight that the entrapment in BIS is a potentially useful strategy to easily immobilise enzymes, while preserving their stability and recycle potential

    Investigating the potential role for RBMY in cancer

    Get PDF
    Introduction: Head and neck squamous cell carcinoma (HNSCC), is a major healthcare concern with a high male prevalence. We hypothesise that the testis specific mRNA splicing regulator, Y-linked RBMY gene, is aberrantly expressed in HNSCC in part promoting HNSCC through ZFY-short splicing. RBMY has been shown to enhance tumour development in male hepatocellular carcinoma (human tissue specimens and transgenic-mouse models) whilst ZFY-short is predicted to have anti-apoptotic properties and the deletion of RBMY locus on Y-chromosome resulted in lowered ZFY-short expression. Thus, we hypothesize that ZFY-short is generated by RBMY and exerts its anti-apoptotic effects to promote male HNSCC. Methods: Due to the coronavirus lockdown, bench work was restricted to 6 months, therefore, I conducted an extended analysis of RBMY expression in human cancer, including a computational analysis of RBMY gene expression with data from the cBioPortal database. In my bench-work, I attempted to establish GFP- RBMY expressing cell lines and conducted fluorescence microscopy, RT- PCR and qPCR to analyse RBMY expression in HNSCC cell lines and its impact on ZFY-short expression. Results: RBMY is expressed in several cancers, with no driver mutations. RBMY has nuclear localisation and is expressed in 93-UV-147T and UM-SCC-104 cell lines (both HPV16-positive HNSCC cell lines), with increased ZFY-short expression observed in UM- SCC-104. Discussion: Despite RBMY having been shown to be an oncogene in male liver cancer, our analysis of cBioPortal data suggests this activity may be restricted to the small minority of tumours of different cancer types that express RBMY. The paralleled expression of RBMY and ZFY-short in our cell lines indicate an association. UMSCC104 cell line originates from a highly an aggressive and recurrent tumour, RBMY is associated with tumour stemness, thus it is possible that via ZFY-short, RBMY could have promoted the aggressive phenotype in this, and in other HNSCCs
    corecore