Aspartylglycosaminuria in the Finnish population: Identification of two point mutations in the heavy chain of glycoasparaginase

Aspartylglycosaminuria is an inherited lysosomal storage disease caused by deficiency of glycoasparaginase (EC 3.5.1.26) and occurs with higher frequency among Finns than other populations. We have purified human glycoasparaginase and determined about 90% of the amino acid sequence of its light subunit and >70% of that of its heavy subunit by Edman degradation and mass spectrometry. Additional sequence data were obtained from the cloning and subsequent nucleotide analysis of a cDNA corresponding to the normal human glycoasparaginase gene. The enzyme is encoded by a single mRNA as a single polypeptide that is posttranslationally processed to generate the subunits and is glycosylated. After preparing first-strand cDNA from leukocyte and fibroblast total RNA, we used the polymerase chain reaction to amplify the glycoasparaginase cDNA of eight Finnish aspartylglycosaminuria patients. We demonstrate that the Finnish patients' mRNA sequence differed from the normal sequence by two single-base changes six nucleotides apart from one another in the heavy chain of glycoasparaginase. The first change resulted in the replacement of arginine by glutamine (R161Q), whereas the second change resulted in a cysteine to serine substitution (C163S). Both mutations resulted in novel restriction endonuclease sites and were present in all eight Finnish aspartylglycosaminuria patients originating from different pedigrees, but they were absent from Finnish and non-Finnish controls and a non-Finnish case of aspartylglycosaminuria. These results indicate molecular homogeneity in aspartylglycosaminuria alleles in the Finnish population

Equilibrium Initialization and Stability of Three-Dimensional Gas Disks

We present a new systematic way of setting up galactic gas disks based on the assumption of detailed hydrodynamic equilibrium. To do this, we need to specify the density distribution and the velocity field which supports the disk. We first show that the required circular velocity has no dependence on the height above or below the midplane so long as the gas pressure is a function of density only. The assumption of disks being very thin enables us to decouple the vertical structure from the radial direction. Based on that, the equation of hydrostatic equilibrium together with the reduced Poisson equation leads to two sets of second-order non-linear differential equation, which are easily integrated to set-up a stable disk. We call one approach `density method' and the other one `potential method'. Gas disks in detailed balance are especially suitable for investigating the onset of the gravitational instability. We revisit the question of global, axisymmetric instability using fully three-dimensional disk simulations. The impact of disk thickness on the disk instability and the formation of spontaneously induced spirals is studied systematically with or without the presence of the stellar potential. In our models, the numerical results show that the threshold value for disk instability is shifted from unity to 0.69 for self-gravitating thick disks and to 0.75 for combined stellar and gas thick disks. The simulations also show that self-induced spirals occur in the correct regions and with the right numbers as predicted by the analytic theory.Comment: 17 pages, 10 figures, accepted by MNRA

Glycosaparaginase from human leukocytes. Inactivation and covalent modification with diazo-oxonorvaline

The apparent active site of human leukocyte glycoasparaginase (N4-(beta-acetylglucosaminyl)-L-asparaginase EC 3.5.1.26) has been studied by labeling with an asparagine analogue, 5-diazo-4-oxo-L-norvaline. Glycoasparaginase was purified 4,600-fold from human leukocytes with an overall recovery of 12%. The purified enzyme has a Km of 110 microM, a Vmax of 34 mumol x l^-1 x min^-1, and a specific activity of 2.2 units/mg protein with N4-(beta-N-acetylglucosaminyl)-L-asparagine as substrate. The carbohydrate content of the enzyme is 15%, and it exhibits a broad pH maximum between 7 and 9. The 88-kDa native enzyme is composed of 19- kDa light (L) chains and 25-kDa heavy (H) chains and it has a heterotetrameric structure of L2H2-type. The glycoasparaginase activity decreases rapidly and irreversibly in the presence of 5-diazo-4-oxo-L- norvaline. At any one concentration of the compound, the inactivation of the enzyme is pseudo-first-order with time. The inhibitory constant, K1, is 80 microM and the second-order rate constant 1.25 x 10^(3) M^-1 min^-1 at pH 7.5. The enzyme activity is competitively protected against this inactivation by its natural substrate, aspartylglucosamine, indicating that this inhibitor binds to the active site or very close to it. The covalent incorporation of [5-14C]diazo-4-oxo-L-norvaline paralleled the loss of the enzymatic activity and one inhibitor binding site was localized to each L-subunit of the heterotetrameric enzyme. Four peptides with the radioactive label were generated, purified by high performance liquid chromatography, and sequenced by Edman degradation. The sequences were overlapping and all contained the amino-terminal tripeptide of the L-chain. By mass spectrometry, the reacting group of 5-diazo-4-oxo-L-norvaline was characterized as 4-oxo-L- norvaline that was bound through an alpha-ketone ether linkage to the hydroxyl group of the amino-terminal amino acid threonine

The neuroscience of sadness: A multidisciplinary synthesis and collaborative review

Sadness is typically characterized by raised inner eyebrows, lowered corners of the mouth, reduced walking speed, and slumped posture. Ancient subcortical circuitry provides a neuroanatomical foundation, extending from dorsal periaqueductal grey to subgenual anterior cingulate, the latter of which is now a treatment target in disorders of sadness. Electrophysiological studies further emphasize a role for reduced left relative to right frontal asymmetry in sadness, underpinning interest in the transcranial stimulation of left dorsolateral prefrontal cortex as an antidepressant target. Neuroimaging studies – including meta-analyses – indicate that sadness is associated with reduced cortical activation, which may contribute to reduced parasympathetic inhibitory control over medullary cardioacceleratory circuits. Reduced cardiac control may – in part – contribute to epidemiological reports of reduced life expectancy in affective disorders, effects equivalent to heavy smoking. We suggest that the field may be moving toward a theoretical consensus, in which different models relating to basic emotion theory and psychological constructionism may be considered as complementary, working at different levels of the phylogenetic hierarchy.Fil: Arias, Juan A.. Swansea University; Reino Unido. Universidad de Santiago de Compostela; EspañaFil: Williams, Claire. Swansea University; Reino UnidoFil: Raghvani, Rashmi. Swansea University; Reino UnidoFil: Aghajani, Moji. No especifíca;Fil: Baez, Sandra. Universidad de los Andes; ColombiaFil: Belzung, Catherine. Universite de Tours; FranciaFil: Booij, Linda. Concordia University Montreal; CanadáFil: Busatto, Geraldo. Universidade de Sao Paulo; BrasilFil: Chiarella, Julian. Concordia University Montreal; CanadáFil: Fu, Cynthia. University Of East London; Reino UnidoFil: Ibañez, Agustin Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Instituto de Neurología Cognitiva. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt | Fundación Favaloro. Instituto de Neurociencia Cognitiva y Traslacional. Fundación Ineco Rosario Sede del Incyt; Argentina. Universidad Adolfo Ibañez; Chile. Universidad Autónoma del Caribe; ColombiaFil: Liddell, Belinda J.. University of New South Wales; AustraliaFil: Lowe, Leroy. No especifíca;Fil: Penninx, Brenda W.J.H.. No especifíca;Fil: Rosa, Pedro. Universidade de Sao Paulo; BrasilFil: Kemp, Andrew H.. Universidade de Sao Paulo; Brasil. Swansea University; Reino Unid

Atomically Precise Graphene Nanoribbon Transistors with Long-Term Stability and Reliability.

Atomically precise graphene nanoribbons (GNRs) synthesized from the bottom-up exhibit promising electronic properties for high-performance field-effect transistors (FETs). The feasibility of fabricating FETs with GNRs (GNRFETs) has been demonstrated, with ongoing efforts aimed at further improving their performance. However, their long-term stability and reliability remain unexplored, which is as important as their performance for practical applications. In this work, we fabricated short-channel FETs with nine-atom-wide armchair GNRs (9-AGNRFETs). We revealed that the on-state (ION) current performance of the 9-AGNRFETs deteriorates significantly over consecutive full transistor on and off logic cycles, which has neither been demonstrated nor previously considered. To address this issue, we deposited a thin ∼10 nm thick atomic layer deposition (ALD) layer of aluminum oxide (Al2O3) directly on these devices. The integrity, compatibility, electrical performance, stability, and reliability, of the GNRFETs before and/or after Al2O3 deposition were comprehensively studied. The results indicate that the observed decline in electrical device performance is most likely due to the degradation of contact resistance over multiple measurement cycles. We successfully demonstrated that the devices with the Al2O3 layer operate well up to several thousand continuous full cycles without any degradation. Our study offers valuable insights into the stability and reliability of GNR transistors, which could facilitate their large-scale integration into practical applications

Multiple mantle upwellings in the transition zone beneath the northern East-African Rift system from relative P-wave travel-time tomography

Mantle plumes and consequent plate extension have been invoked as the likely cause of East African Rift volcanism. However, the nature of mantle upwelling is debated, with proposed configurations ranging from a single broad plume connected to the large low-shear-velocity province beneath Southern Africa, the so-called African Superplume, to multiple lower-mantle sources along the rift. We present a new P-wave travel-time tomography model below the northern East-African, Red Sea, and Gulf of Aden rifts and surrounding areas. Data are from stations that span an area from Madagascar to Saudi Arabia. The aperture of the integrated data set allows us to image structures of 100 km length-scale down to depths of 700– 800 km beneath the study region. Our images provide evidence of two clusters of low-velocity structures consisting of features with diameter of 100–200 km that extend through the transition zone, the first beneath Afar and a second just west of the Main Ethiopian Rift, a region with off-rift volcanism. Considering seismic sensitivity to temperature, we interpret these features as upwellings with excess temperatures of 100 6 50 K. The scale of the upwellings is smaller than expected for lower mantle plume sources. This, together with the change in pattern of the low-velocity anomalies across the base of the transition zone, suggests that ponding or flow of deep-plume material below the transition zone may be spawning these upper mantle upwellings

An Esrrb and nanog cell fate regulatory module controlled by feed forward loop interactions

Cell fate decisions during development are governed by multi-factorial regulatory mechanisms including chromatin remodeling, DNA methylation, binding of transcription factors to specific loci, RNA transcription and protein synthesis. However, the mechanisms by which such regulatory 'dimensions' coordinate cell fate decisions are currently poorly understood. Here we quantified the multi-dimensional molecular changes that occur in mouse embryonic stem cells (mESCs) upon depletion of Estrogen related receptor beta (Esrrb), a key pluripotency regulator. Comparative analyses of expression changes subsequent to depletion of Esrrb or Nanog, indicated that a system of interlocked feed-forward loops involving both factors, plays a central part in regulating the timing of mESC fate decisions. Taken together, our meta-analyses support a hierarchical model in which pluripotency is maintained by an Oct4-Sox2 regulatory module, while the timing of differentiation is regulated by a Nanog-Esrrb module

Les ateliers du hameau Les Noires Terres à Messein (Meurthe-et-Moselle, Lorraine, France) :

L’occupation altomédiévale (VIe-VIIIe s.) au lieu-dit Les Noires Terres sur la commune de Messein, au sud de Nancy (Meurthe-et-Moselle, France, fouille 2003-2004), associe des unités composées d’un bâtiment d’habitation et de structures de type agricole (greniers, silos, enclos, cabanes excavées…) à des ateliers de production et de travail du fer (préparation du minerai, fabrication du charbon de bois, fourneaux de réduction, forgeage du fer). La présence des déchets relevant d’une chaîne opératoire complète (de la préparation du minerai à l’élaboration de produits finis), documentée par l’étude paléométallurgique, ainsi que le volume de production estimé au vu de leur quantité (plusieurs dizaines de tonnes de fer), suggèrent qu’il s’agit de l’activité principale des occupants et non pas d’une activité d’appoint aux pratiques agricoles. La nature de l’occupation est donc discutée : les vestiges découverts correspondraient aux unités d’habitation d’artisans spécialisés, avec leurs ateliers, comportant l’ensemble des installations et équipements nécessaires à leur subsistance et à leur vie quotidienne. On peut ainsi émettre l’hypothèse qu’il s’agit d’une des formes d’organisation de la production du fer dans le monde franc au cours du premier Moyen Âge, et qu’elle correspond peut-être à ce que nous laissent entrevoir les polyptiques de la période carolingienne.The Altomedieval occupation (6th-8th c.) at Les Noires Terres in Messein, to the south of Nancy (Meurthe-et-Moselle, France, excavation 2003-2004), associates elements composed of a dwelling and agricultural structures (granaries, silos, enclosures, excavated huts, etc.) with iron production and transformation workshops (iron ore preparation, wood charcoal production, reduction furnaces, iron forging). The presence of waste products corresponding to a complete chaîne opératoire (production sequence) (from iron ore preparation to finished products), documented by the paleo-metallurgical study and the production volume estimated from their quantity (several dozen tons of iron), suggest that this was the main activity of the occupants, rather than an activity secondary to agricultural activities. The nature of the occupation is thus discussed : the remains discovered could correspond to the dwellings of the specialized artisans, with their workshops, including all the installations and equipment necessary for their subsistence and daily life. We can thus propose the hypothesis that this was one of the forms of iron production organization employed by the Franks during the Early Middle Ages, and that if might correspond to that which is suggested by the polyptyques of the Carolingian period.Die frühmittelalterliche Besiedlung (6.-8. Jh.) von Les Noires Terres auf dem Gebiet der Gemeinde Messein, südlich von Nancy (Departement Meurthe-et-Moselle, Frankreich, Ausgrabung 2003-2004), besteht aus Siedlungseinheiten, die sich jeweils aus einem Wohnbau mit landwirtschaftlichen Einrichtungen (Speicherbauten, Silos, Einfriedungen, Grubenhäuser…) und Werkstätten für die Eisengewinnung und -verarbeitung (Erzaufbereitung, Holzkohlengewinnung, Rennöfen, Eisenschmieden) zusammensetzen. Die Abfälle, die von einem kompletten, durch die paläometallurgische Studie dokumentierten Verhüttungsprozess (von der Erzaufbereitung bis hin zur Formgebung der Endprodukte) zeugen, sowie das anhand der Abfälle geschätzte Produktionsvolumen (mehrere Dutzend Tonnen Eisen) legen nahe, dass es sich hier um die Hauptbeschäftigung der Bewohner handelte und nicht um eine Nebentätigkeit. Demzufolge steht die Art der Besiedlung zur Diskussion: Die Funde und Befunde würden einer auf die Eisengewinnung und -verarbeitung spezialisierte Handwerkersiedlung entsprechen mit allen für die Arbeit und den Alltag der Bewohner notwendigen Anlagen und Einrichtungen, Wohnhäusern und Werkstätten. So können wir die Hypothese vorlegen, dass es sich um eine der Organisationsformen der frühmittelalterlichen fränkischen Eisenmetallurgie handelt, welche die Urbare der karolingischen Periode erahnen lassen

Inorganic Nitrate Promotes the Browning of White Adipose Tissue Through the Nitrate-Nitrite-Nitric Oxide Pathway

Inorganic nitrate was once considered an oxidation end product of nitric oxide metabolism with little biological activity. However, recent studies have demonstrated that dietary nitrate can modulate mitochondrial function in man and is effective in reversing features of the metabolic syndrome in mice. Using a combined histological, metabolomics, and transcriptional and protein analysis approach, we mechanistically defined that nitrate not only increases the expression of thermogenic genes in brown adipose tissue but also induces the expression of brown adipocyte–specific genes and proteins in white adipose tissue, substantially increasing oxygen consumption and fatty acid β-oxidation in adipocytes. Nitrate induces these phenotypic changes through a mechanism distinct from known physiological small molecule activators of browning, the recently identified nitrate-nitrite-nitric oxide pathway. The nitrate-induced browning effect was enhanced in hypoxia, a serious comorbidity affecting white adipose tissue in obese individuals, and corrected impaired brown adipocyte–specific gene expression in white adipose tissue in a murine model of obesity. Because resulting beige/brite cells exhibit antiobesity and antidiabetic effects, nitrate may be an effective means of inducing the browning response in adipose tissue to treat the metabolic syndrome

Using a case-study approach to improve the Madden-Julian oscillation in the Hadley Centre model

In its default configuration, the Hadley Centre climate model (GA2.0) simulates roughly one-half the observed level of Madden–Julian oscillation activity, with MJO events often lasting fewer than seven days. We use initialised, climate-resolution hindcasts to examine the sensitivity of the GA2.0 MJO to a range of changes in sub-grid parameterisations and model configurations. All 22 changes are tested for two cases during the Years of Tropical Convection. Improved skill comes only from (a) disabling vertical momentum transport by convection and (b) increasing mixing entrainment and detrainment for deep and mid-level convection. These changes are subsequently tested in a further 14 hindcast cases; only (b) consistently improves MJO skill, from 12 to 22 days. In a 20-year integration, (b) produces near-observed levels of MJO activity, but propagation through the Maritime Continent remains weak. With default settings, GA2.0 produces precipitation too readily, even in anomalously dry columns. Implementing (b) decreases the efficiency of convection, permitting instability to build during the suppressed MJO phase and producing a more favourable environment for the active phase. The distribution of daily rain rates is more consistent with satellite data; default entrainment produces 6–12 mm/day too frequently. These results are consistent with recent studies showing that greater sensitivity of convection to moisture improves the representation of the MJO