Double fluorescent knock-in mice to investigate endogenous mu-delta opioid heteromer subscellular distribution.

The heteromerization of Mu (MOP) and delta (DOP) opioid receptors has been extensively studied in heterologous systems. These studies demonstrated significant functional interaction of MOP and DOP evidenced by new pharmacological properties and intracellular signalling in transfected cells co-expressing the receptors. Due to the lack of appropriate tools for receptor visualization, such as specific antibodies, the pharmacological and functional properties of MOP-DOP heteromers in cells naturally expressing these receptors remains poorly understood. To address endogenous MOP-DOP heteromer trafficking and signalling in vivo and in primary neuronal cultures, we generated a double knock-in mouse line expressing functional fluorescent versions of DOP and MOP receptors. This mouse model has successfully been used to map the neuroanatomic distribution of the receptors and to identify brain regions in which the MOP-DOP heteromers are expressed. Here, we describe a method to quantitatively and automatically analyze changes in the subcellular distribution of MOP-DOP heteromers in primary hippocampal culture from this mouse model. This approach provides a unique tool to address specificities of endogenous MOP-DOP heteromer trafficking

Editorial: Emerging Roles of TRP Channels in Brain Pathology

The mammalian transient receptor potential (TRP) ion channel superfamily comprises six subfamilies, TRPC (canonical), TRPV (vanilloid), TRPM (melastatin), TRPA (ankyrin), TRPP (polycystin), and TRPML (mucolipin) (Ramsey et al., 2006; Venkatachalam and Montell, 2007). TRP channels are tetrameric and each subunit contains intracellular N- and C-termini and six membrane-spanning segments, with the fifth and sixth segments and the re-entrant loop between them forming the ion-conducting pore (Cao, 2020). They function as non-selective cation channels, with prominent Ca2+ permeability for most of them, and are activated by diverse physical, chemical and biological stimuli. Their Ca2+ permeability, poly-modal activation and wide expression place these channels in a vital position mediating Ca2+ signalling in a range of physiological processes. Not surprisingly, accumulating evidence supports an important role for the TRP channels in the pathogenesis of numerous diseases (Nilius et al., 2007). Many TRP channels are expressed in the brain. This Research Topic, including 14 review and original research articles, offers critical and new insights into the role of TRP channels, particularly the Ca2+-permeable ones, in multiple brain pathologies

Evolutionary Analysis of the Bacillus subtilis Genome Reveals New Genes Involved in Sporulation

Bacilli can form dormant, highly resistant, and metabolically inactive spores to cope with extreme environmental challenges. In this study, we examined the evolutionary age of Bacillus subtilis sporulation genes using the approach known as genomic phylostratigraphy. We found that B. subtilis sporulation genes cluster in several groups that emerged at distant evolutionary time-points, suggesting that the sporulation process underwent several stages of expansion. Next, we asked whether such evolutionary stratification of the genome could be used to predict involvement in sporulation of presently uncharacterized genes (y-genes). We individually inactivated a representative sample of uncharacterized genes that arose during the same evolutionary periods as the known sporulation genes and tested the resulting strains for sporulation phenotypes. Sporulation was significantly affected in 16 out of 37 (43%) tested strains. In addition to expanding the knowledge base on B. subtilis sporulation, our findings suggest that evolutionary age could be used to help with genome mining

Comparative genomics study reveals Red Sea Bacillus with characteristics associated with potential microbial cell factories (MCFs)

© 2019, The Author(s). Recent advancements in the use of microbial cells for scalable production of industrial enzymes encourage exploring new environments for efficient microbial cell factories (MCFs). Here, through a comparison study, ten newly sequenced Bacillus species, isolated from the Rabigh Harbor Lagoon on the Red Sea shoreline, were evaluated for their potential use as MCFs. Phylogenetic analysis of 40 representative genomes with phylogenetic relevance, including the ten Red Sea species, showed that the Red Sea species come from several colonization events and are not the result of a single colonization followed by speciation. Moreover, clustering reactions in reconstruct metabolic networks of these Bacillus species revealed that three metabolic clades do not fit the phylogenetic tree, a sign of convergent evolution of the metabolism of these species in response to special environmental adaptation. We further showed Red Sea strains Bacillus paralicheniformis (Bac48) and B. halosaccharovorans (Bac94) had twice as much secreted proteins than the model strain B. subtilis 168. Also, Bac94 was enriched with genes associated with the Tat and Sec protein secretion system and Bac48 has a hybrid PKS/NRPS cluster that is part of a horizontally transferred genomic region. These properties collectively hint towards the potential use of Red Sea Bacillus as efficient protein secreting microbial hosts, and that this characteristic of these strains may be a consequence of the unique ecological features of the isolation environment

INTERET DU DOSAGE DU NT- PROBNP DANS LE DIAGNOSTIC DIFFERENTIEL D’UNE DYSPNEE AIGUE AU SERVICE DES

Objective: the N-terminal fraction of the precursor of the natriuretic peptide of type B (NT-proBNP) is a marker of cardiac failure. In this work we evaluated the performances as regards diagnosis of a dyspnea which this marker can bring to the urgentists of our formation in order to direct in an adequate way the patients dyspneic, towards the various services of the Military hospital of Instruction Mohammed V Rabat. Material and method: our study was carried out among 40 patients dealt with by the team of the service of the urgencies of the Military hospital of Instruction Mohammed V for nontraumatic acute dyspnea accompanied or not by thoracic pain. The Middle Age of the studied population is 54 years with the extreme ones going from 30 to 78 years. The patients were studied on the clinical level by the medical antecedents; risk factors cardiovascular and on the biological level by the ionogramme, the NFS, gases of blood and the proportioning of the NT-proBNP. Results: the patients are classified in three groups: On the one hand according to the rate of NT-proBNP. 27 patients presented values of NT-proBNP > 1200 pg/ml, but it was not retained that 23 patients because the 4 others had been excluded because of the impaired renal function. The clinical and radiological diagnosis was obvious among 17 patients is 74%. Among 6 other patients (26%), the rate of high NT-proBNP justified the orientation of these patients in cardiology for additional investigations. The diagnoses retained by the cardiologists confirmed the cardiac presence of pathology among these patients. As for the patients whose rate of NT-proBNP lies between 250 and 1200 pg/ml (N = 3), their orientation took account of the clinical context. 10 patients presented values of NT-proBNP 1200 pg/ml, mais on n’a retenu que 23 patients car les 4 autres avaient été exclus à cause de l’insuffisance rénale. Le diagnostic clinique et radiologique était évident chez 17 patients soit 74%. Chez les 6 autres patients (26%), le taux de NT-proBNP élevé a justifié l’orientation de ces patients en cardiologie pour des investigations supplémentaires. Les diagnostics retenus par les cardiologues confirmaient la présence de pathologie cardiaque chez ces malades. Quant aux patients dont le taux de NT-proBNP est compris entre 250 et 1200 pg/ml (n = 3), leur orientation a tenu compte du contexte clinique. 10 patients présentaient des valeurs de NT-proBNP < 250 pg/ml. Aucun événement cardiaque n’a été décelé par les examens complémentaires réalisés à posteriori. D’autre part, en fonction des données clinique et paraclinique le médecin urgentiste a orienté 16 patients en pneumologie 19 patients en cardiologie 5 patients en néphrologie et réanimation. Conclusion : le NT-proBNP est d’une fiabilité manifeste par rapport aux données cliniques et paracliniques, permettant non seulement une prise en charge rapide des patients mais aussi d’éviter la prescription de bilans non justifiés  parfois très coûteux et une prolongation de la durée d’hospitalisation du malade

Low Concentrations of Vitamin C Reduce the Synthesis of Extracellular Polymers and Destabilize Bacterial Biofilms

Extracellular polymeric substances (EPS) produced by bacteria form a matrix supporting the complex three-dimensional architecture of biofilms. This EPS matrix is primarily composed of polysaccharides, proteins and extracellular DNA. In addition to supporting the community structure, the EPS matrix protects bacterial biofilms from the environment. Specifically, it shields the bacterial cells inside the biofilm, by preventing antimicrobial agents from getting in contact with them, thereby reducing their killing effect. New strategies for disrupting the formation of the EPS matrix can therefore lead to a more efficient use of existing antimicrobials. Here we examined the mechanism of the known effect of vitamin C (sodium ascorbate) on enhancing the activity of various antibacterial agents. Our quantitative proteomics analysis shows that non-lethal concentrations of vitamin C inhibit bacterial quorum sensing and other regulatory mechanisms underpinning biofilm development. As a result, the EPS biosynthesis in reduced, and especially the polysaccharide component of the matrix is depleted. Once the EPS content is reduced beyond a critical point, bacterial cells get fully exposed to the medium. At this stage, the cells are more susceptible to killing, either by vitamin C-induced oxidative stress as reported here, or by other antimicrobials or treatments

Aspects of astrocyte energy metabolism, amino acid neurotransmitter homoeostasis and metabolic compartmentation

Astrocytes are key players in brain function; they are intimately involved in neuronal signalling processes and their metabolism is tightly coupled to that of neurons. In the present review, we will be concerned with a discussion of aspects of astrocyte metabolism, including energy-generating pathways and amino acid homoeostasis. A discussion of the impact that uptake of neurotransmitter glutamate may have on these pathways is included along with a section on metabolic compartmentation

Glutamine synthetase gene expression during the regeneration of the annelid Enchytraeus japonensis

Enchytraeus japonensis is a highly regenerative oligochaete annelid that can regenerate a complete individual from a small body fragment in 4–5 days. In our previous study, we performed complementary deoxyribonucleic acid subtraction cloning to isolate genes that are upregulated during E. japonensis regeneration and identified glutamine synthetase (gs) as one of the most abundantly expressed genes during this process. In the present study, we show that the full-length sequence of E. japonensis glutamine synthetase (EjGS), which is the first reported annelid glutamine synthetase, is highly similar to other known class II glutamine synthetases. EjGS shows a 61–71% overall amino acid sequence identity with its counterparts in various other animal species, including Drosophila and mouse. We performed detailed expression analysis by in situ hybridization and reveal that strong gs expression occurs in the blastemal regions of regenerating E. japonensis soon after amputation. gs expression was detectable at the cell layer covering the wound and was found to persist in the epidermal cells during the formation and elongation of the blastema. Furthermore, in the elongated blastema, gs expression was detectable also in the presumptive regions of the brain, ventral nerve cord, and stomodeum. In the fully formed intact head, gs expression was also evident in the prostomium, brain, the anterior end of the ventral nerve cord, the epithelium of buccal and pharyngeal cavities, the pharyngeal pad, and in the esophageal appendages. In intact E. japonensis tails, gs expression was found in the growth zone in actively growing worms but not in full-grown individuals. In the nonblastemal regions of regenerating fragments and in intact worms, gs expression was also detected in the nephridia, chloragocytes, gut epithelium, epidermis, spermatids, and oocytes. These results suggest that EjGS may play roles in regeneration, nerve function, cell proliferation, nitrogenous waste excretion, macromolecule synthesis, and gametogenesis

Working with argan cake: a new etiology for hypersensitivity pneumonitis

International audienceAbstractBackgroundArgan is now used worldwide in numerous cosmetic products. Nine workers from a cosmetic factory were examined in our occupational medicine department, following the diagnosis of a case of hypersensitivity pneumonitis (HP) related to handling of argan cakes.MethodsOperators were exposed to three forms of argan (crude granulates, powder or liquid) depending on the step of the process. All workers systematically completed standardized questionnaires on occupational and medical history, followed by medical investigations, comprising, in particular, physical examination and chest X-rays, total IgE and a systematic screening for specific serum antibodies directed against the usual microbial agents of domestic and farmer’s HP and antigens derived from microbiological culture and extracts of various argan products. Subjects with episodes of flu-like syndrome several hours after handling argan cakes, were submitted to a one-hour challenge to argan cakes followed by physical examination, determination of Carbon Monoxide Diffusing Capacity (DLCO) and chest CT-scan on day 2, and, when necessary, bronchoalveolar lavage on day 4.ResultsSix of the nine workers experienced flu-like symptoms within 8 hours after argan handling. After challenge, two subjects presented a significant decrease of DLCO and alveolitis with mild lymphocytosis, and one presented ground glass opacities. These two patients and another patient presented significant arcs to both granulates and non-sterile powder. No reactivity was observed to sterile argan finished product, antigens derived from argan cultures (various species of Bacillus) and Streptomyces marokkonensis (reported in the literature to contaminate argan roots).ConclusionsWe report the first evidence of hypersensitivity pneumonitis related to argan powder in two patients. This implies preventive measures to reduce their exposure and clinical survey to diagnose early symptoms. As exposure routes are different and antibodies were observed against argan powder and not the sterile form, consumers using argan-based cosmetics should not be concerned