182 research outputs found

    Virtual Fluidization Labs to Assist Unit Operations Courses

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    As technology advances, educational platforms are changing, evolving towards partially or entirely virtual environments. New emerging virtual tools are used to enhance topics discussed in lecture settings. In chemical engineering education, one of the fundamental courses for undergraduate pathways is the unit operations labs; however, physical lab settings have a few drawbacks. Costs required to store and maintain the equipment in the physical labs can add up, and a limited number of students can access the equipment in labs. Thus, virtual lab platforms are viable and economical options for either an alternative or a lab preparation tool. For this study, a fluidized bed virtual lab was implemented with a cohort of students to study the virtual lab effectiveness. The fluidized bed virtual lab is built on the Ergun equation to assist users to successfully correlate the relationships between specific variables, such as particle diameters, to fluidized bed behavior while comparing to experimental data. From that understanding, the user would be able to utilize the experience from the virtual lab to navigate data collection and analysis when in a physical fluidized bed unit operations lab with more confidence and understanding. Therefore, the fluidized bed virtual lab can be incorporated into a course as an additional educational resource

    Kidins220/ARMS modulates brain morphology and anxiety-like traits in adult mice

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    open11: Kinase D interacting substrate of 220 kDa (Kidins220), also known as ankyrin repeat-rich membrane spanning (ARMS), is a transmembrane scaffold protein that participates in fundamental aspects of neuronal physiology including cell survival, differentiation, and synaptic plasticity. The Kidins220 constitutive knockout line displays developmental defects in the nervous and cardiovascular systems that lead to embryonic lethality, which has so far precluded the study of this protein in the adult. Moreover, Kidins220 mRNA is tightly regulated by alternative splicing, whose impact on nervous system physiology has not yet been addressed in vivo. Here, we have asked to what extent the absence of Kidins220 splicing and the selective knockout of Kidins220 impact on adult brain homeostasis. To answer this question, we used a floxed line that expresses only the full-length, non-spliced Kidins220 mRNA, and a forebrain-specific, CaMKII-Cre driven Kidins220 conditional knockout (cKO) line. Kidins220 cKO brains are characterized by enlarged ventricles in the absence of cell death, and by deficient dendritic arborization in several cortical regions. The deletion of Kidins220 leads to behavioral changes, such as reduced anxiety-like traits linked to alterations in TrkB-BDNF signaling and sex-dependent alterations of hippocampal-dependent spatial memory. Kidins220 floxed mice present similarly enlarged brain ventricles and increased associative memory. Thus, both the absolute levels of Kidins220 expression and its splicing pattern are required for the correct brain development and related expression of behavioral phenotypes. These findings are relevant in light of the increasing evidence linking mutations in the human KIDINS220 gene to the onset of severe neurodevelopmental disorders.openAlmacellas-Barbanoj, Amanda; Albini, Martina; Satapathy, Annyesha; Jaudon, Fanny; Michetti, Caterina; Krawczun-Rygmaczewska, Alicja; Huang, Huiping; Manago, Francesca; Papaleo, Francesco; Benfenati, Fabio; Cesca, FabriziaAlmacellas-Barbanoj, Amanda; Albini, Martina; Satapathy, Annyesha; Jaudon, Fanny; Michetti, Caterina; Krawczun-Rygmaczewska, Alicja; Huang, Huiping; Manago, Francesca; Papaleo, Francesco; Benfenati, Fabio; Cesca, Fabrizi

    The H-NS regulator plays a role in the stress induced by carbapenemase expression in acinetobacter baumannii

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    Disruption of the histone-like nucleoid structuring protein (H-NS) was shown to affect the ability of Gram-negative bacteria to regulate genes associated with virulence, persistence, stress response, quorum sensing, biosynthesis pathways, and cell adhesion. Here, we used the expression of metallo-β-lactamases (MBLs), known to elicit envelope stress by the accumulation of toxic precursors in the periplasm, to interrogate the role of H-NS in Acinetobacter baumannii, together with other stressors. Using a multidrug-resistant A. baumannii strain, we observed that H-NS plays a role in alleviating the stress triggered by MBL toxic precursors and counteracts the effect of DNA-damaging agents, supporting its role in stress response. IMPORTANCE Carbapenem-resistant A. baumannii (CRAB) is recognized as one of the most threatening Gram-negative bacilli. H-NS is known to play a role in controlling the transcription of a variety of different genes, including those associated with the stress response, persistence, and virulence. In the present work, we uncovered a link between the role of H-NS in the A. baumannii stress response and its relationship with the envelope stress response and resistance to DNA-damaging agents. Overall, we posit a new role of H-NS, showing that H-NS serves to endure envelope stress and could also be a mechanism that alleviates the stress induced by MBL expression in A. baumannii. This could be an evolutionary advantage to further resist the action of carbapenems.Fil: Huang, Fanny. California State University. College Of Natural Science And Mathematics; Estados UnidosFil: Fitchett, Noelle. California State University. College Of Natural Science And Mathematics; Estados UnidosFil: Razo Gutierrez, Chelsea. California State University. College Of Natural Science And Mathematics; Estados UnidosFil: Le, Casin. California State University. College Of Natural Science And Mathematics; Estados UnidosFil: Martinez, Jasmine. California State University. College Of Natural Science And Mathematics; Estados UnidosFil: Ra, Grace. California State University. College Of Natural Science And Mathematics; Estados UnidosFil: Lopez, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Gonzalez, Lisandro Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Sieira, Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Vila, Alejandro Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Bonomo, Robert A.. Louis Stokes Cleveland Va Medical Center; Estados Unidos. Case Western Reserve University School of Medicine; Estados UnidosFil: Ramirez, Maria Soledad. California State University. College Of Natural Science And Mathematics; Estados Unido

    Loss-of-function mutations in SIM1 contribute to obesity and Prader-Willi-like features

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    Sim1 haploinsufficiency in mice induces hyperphagic obesity and developmental abnormalities of the brain. In humans, abnormalities in chromosome 6q16, a region that includes SIM1, were reported in obese children with a Prader-Willi–like syndrome; however, SIM1 involvement in obesity has never been conclusively demonstrated. Here, SIM1 was sequenced in 44 children with Prader-Willi–like syndrome features, 198 children with severe early-onset obesity, 568 morbidly obese adults, and 383 controls. We identified 4 rare variants (p.I128T, p.Q152E, p.R581G, and p.T714A) in 4 children with Prader-Willi–like syndrome features (including severe obesity) and 4 other rare variants (p.T46R, p.E62K, p.H323Y, and p.D740H) in 7 morbidly obese adults. By assessing the carriers’ relatives, we found a significant contribution of SIM1 rare variants to intra-family risk for obesity. We then assessed functional effects of the 8 substitutions on SIM1 transcriptional activities in stable cell lines using luciferase gene reporter assays. Three mutations showed strong loss-of-function effects (p.T46R, p.H323Y, and p.T714A) and were associated with high intra-family risk for obesity, while the variants with mild or no effects on SIM1 activity were not associated with obesity within families. Our genetic and functional studies demonstrate a firm link between SIM1 loss of function and severe obesity associated with, or independent of, Prader-Willi–like features.Amélie Bonnefond, Anne Raimondo, Fanny Stutzmann, Maya Ghoussaini, Shwetha Ramachandrappa, David C. Bersten, Emmanuelle Durand, Vincent Vatin, Beverley Balkau, Olivier Lantieri, Violeta Raverdy, François Pattou, Wim Van Hul, Luc Van Gaal, Daniel J. Peet, Jacques Weill, Jennifer L. Miller, Fritz Horber, Anthony P. Goldstone, Daniel J. Driscoll, John B. Bruning, David Meyre, Murray L. Whitelaw and Philippe Frogue

    Functioning of the dimeric GABA(B) receptor extracellular domain revealed by glycan wedge scanning

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    The G-protein-coupled receptor (GPCR) activated by the neurotransmitter GABA is made up of two subunits, GABA(B1) and GABA(B2). GABA(B1) binds agonists, whereas GABA(B2) is required for trafficking GABA(B1) to the cell surface, increasing agonist affinity to GABA(B1), and activating associated G proteins. These subunits each comprise two domains, a Venus flytrap domain (VFT) and a heptahelical transmembrane domain (7TM). How agonist binding to the GABA(B1) VFT leads to GABA(B2) 7TM activation remains unknown. Here, we used a glycan wedge scanning approach to investigate how the GABA(B) VFT dimer controls receptor activity. We first identified the dimerization interface using a bioinformatics approach and then showed that introducing an N-glycan at this interface prevents the association of the two subunits and abolishes all activities of GABA(B2), including agonist activation of the G protein. We also identified a second region in the VFT where insertion of an N-glycan does not prevent dimerization, but blocks agonist activation of the receptor. These data provide new insight into the function of this prototypical GPCR and demonstrate that a change in the dimerization interface is required for receptor activation

    Conditions of malaria transmission in Dakar from 2007 to 2010

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    Background: Previous studies in Dakar have highlighted the spatial and temporal heterogeneity of Anopheles gambiae s.l. biting rates. In order to improve the knowledge of the determinants of malaria transmission in this city, the present study reports the results of an extensive entomological survey that was conducted in 45 areas in Dakar from 2007 to 2010. Methods: Water collections were monitored for the presence of anopheline larvae. Adult mosquitoes were sampled by human landing collection. Plasmodium falciparum circumsporozoite (CSP) protein indexes were measured by ELISA (enzyme-linked immunosorbent assay), and the entomological inoculation rates were calculated. Results: The presence of anopheline larvae were recorded in 1,015 out of 2,683 observations made from 325 water collections. A water pH of equal to or above 8.0, a water temperature that was equal to or above 30 degrees C, the absence of larvivorous fishes, the wet season, the presence of surface vegetation, the persistence of water and location in a slightly urbanised area were significantly associated with the presence of anopheline larvae and/or with a higher density of anopheline larvae. Most of the larval habitats were observed in public areas, i.e., freely accessible. A total of 496,310 adult mosquitoes were caught during 3096 person-nights, and 44967 of these specimens were identified as An. gambiae s.l. The mean An. gambiae s.l. human-biting rate ranged from 0.1 to 248.9 bites per person per night during the rainy season. Anopheles arabiensis (93.14%), Anopheles melas (6.83%) and An. gambiae s.s. M form (0.03%) were the three members of the An. gambiae complex. Fifty-two An. arabiensis and two An. melas specimens were CSP-positive, and the annual CSP index was 0.64% in 2007, 0.09% in 2008-2009 and 0.12% in 2009-2010. In the studied areas, the average EIR ranged from 0 to 17.6 infected bites per person during the entire transmission season. Conclusion: The spatial and temporal heterogeneity of An. gambiae s.l. larval density, adult human-biting rate (HBR) and malaria transmission in Dakar has been confirmed, and the environmental factors associated with this heterogeneity have been identified. These results pave the way for the creation of malaria risk maps and for a focused anti-vectorial control strategy

    Normalisation to Blood Activity Is Required for the Accurate Quantification of Na/I Symporter Ectopic Expression by SPECT/CT in Individual Subjects

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    The utilisation of the Na/I symporter (NIS) and associated radiotracers as a reporter system for imaging gene expression is now reaching the clinical setting in cancer gene therapy applications. However, a formal assessment of the methodology in terms of normalisation of the data still remains to be performed, particularly in the context of the assessment of activities in individual subjects in longitudinal studies. In this context, we administered to mice a recombinant, replication-incompetent adenovirus encoding rat NIS, or a human colorectal carcinoma cell line (HT29) encoding mouse NIS. We used 99mTc pertechnetate as a radiotracer for SPECT/CT imaging to determine the pattern of ectopic NIS expression in longitudinal kinetic studies. Some animals of the cohort were culled and NIS expression was measured by quantitative RT-PCR and immunohistochemistry. The radioactive content of some liver biopsies was also measured ex vivo. Our results show that in longitudinal studies involving datasets taken from individual mice, the presentation of non-normalised data (activity expressed as %ID/g or %ID/cc) leads to ‘noisy’, and sometimes incoherent, results. This variability is due to the fact that the blood pertechnetate concentration can vary up to three-fold from day to day. Normalisation of these data with blood activities corrects for these inconsistencies. We advocate that, blood pertechnetate activity should be determined and used to normalise the activity measured in the organ/region of interest that expresses NIS ectopically. Considering that NIS imaging has already reached the clinical setting in the context of cancer gene therapy, this normalisation may be essential in order to obtain accurate and predictive information in future longitudinal clinical studies in biotherapy

    Bi-allelic ACBD6 variants lead to a neurodevelopmental syndrome with progressive and complex movement disorders

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    The acyl-CoA-binding domain-containing protein 6 (ACBD6) is ubiquitously expressed, plays a role in the acylation of lipids and proteins, and regulates the N-myristoylation of proteins via N-myristoyltransferase enzymes (NMTs). However, its precise function in cells is still unclear, as is the consequence of ACBD6 defects on human pathophysiology. Utilizing exome sequencing and extensive international data sharing efforts, we identified 45 affected individuals from 28 unrelated families (consanguinity 93%) with bi-allelic pathogenic, predominantly loss-of-function (18/20) variants in ACBD6. We generated zebrafish and Xenopus tropicalis acbd6 knockouts by CRISPR/Cas9 and characterized the role of ACBD6 on protein N-myristoylation with YnMyr chemical proteomics in the model organisms and human cells, with the latter also being subjected further to ACBD6 peroxisomal localization studies. The affected individuals (23 males and 22 females), with ages ranging from 1 to 50 years old, typically present with a complex and progressive disease involving moderate-to-severe global developmental delay/intellectual disability (100%) with significant expressive language impairment (98%), movement disorders (97%), facial dysmorphism (95%), and mild cerebellar ataxia (85%) associated with gait impairment (94%), limb spasticity/hypertonia (76%), oculomotor (71%) and behavioural abnormalities (65%), overweight (59%), microcephaly (39%) and epilepsy (33%). The most conspicuous and common movement disorder was dystonia (94%), frequently leading to early-onset progressive postural deformities (97%), limb dystonia (55%), and cervical dystonia (31%). A jerky tremor in the upper limbs (63%), a mild head tremor (59%), parkinsonism/hypokinesia developing with advancing age (32%), and simple motor and vocal tics were among other frequent movement disorders. Midline brain malformations including corpus callosum abnormalities (70%), hypoplasia/agenesis of the anterior commissure (66%), short midbrain and small inferior cerebellar vermis (38% each), as well as hypertrophy of the clava (24%) were common neuroimaging findings. acbd6-deficient zebrafish and Xenopus models effectively recapitulated many clinical phenotypes reported in patients including movement disorders, progressive neuromotor impairment, seizures, microcephaly, craniofacial dysmorphism, and midbrain defects accompanied by developmental delay with increased mortality over time. Unlike ACBD5, ACBD6 did not show a peroxisomal localisation and ACBD6-deficiency was not associated with altered peroxisomal parameters in patient fibroblasts. Significant differences in YnMyr-labelling were observed for 68 co- and 18 post-translationally N-myristoylated proteins in patient-derived fibroblasts. N-Myristoylation was similarly affected in acbd6-deficient zebrafish and Xenopus tropicalis models, including Fus, Marcks, and Chchd-related proteins implicated in neurological diseases. The present study provides evidence that bi-allelic pathogenic variants in ACBD6 lead to a distinct neurodevelopmental syndrome accompanied by complex and progressive cognitive and movement disorders

    Integrated Molecular Characterization of Uterine Carcinosarcoma

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    SummaryWe performed genomic, epigenomic, transcriptomic, and proteomic characterizations of uterine carcinosarcomas (UCSs). Cohort samples had extensive copy-number alterations and highly recurrent somatic mutations. Frequent mutations were found in TP53, PTEN, PIK3CA, PPP2R1A, FBXW7, and KRAS, similar to endometrioid and serous uterine carcinomas. Transcriptome sequencing identified a strong epithelial-to-mesenchymal transition (EMT) gene signature in a subset of cases that was attributable to epigenetic alterations at microRNA promoters. The range of EMT scores in UCS was the largest among all tumor types studied via The Cancer Genome Atlas. UCSs shared proteomic features with gynecologic carcinomas and sarcomas with intermediate EMT features. Multiple somatic mutations and copy-number alterations in genes that are therapeutic targets were identified
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