The function of SIFamide, PDF, and further neuropeptides in the circadian system of Rhyparobia maderae

Der täglich Wechsel von Hell- und Dunkelphasen führte während der Evolution zur Entwicklung innerer Uhren in nahezu allen Organismen. In der Schabe Rhyparobia maderae lokalisierten Läsions- und Transplantationsexperimente die innere Uhr in der akzessorischen Medulla (AME). Dieses kleine birnenförmige Neuropil am ventromedianen Rand der Medulla ist mit etwa 240 Neuronen assoziiert, die eine hohe Anzahl an zum Teil kolokalisierten Neuropeptiden und Neurotransmittern exprimieren. Diese Signalstoffe scheinen essentiell zu sein für die Synchronisation der inneren Uhr mit der Umwelt, der Kopplung der beiden bilateralen AME, der Aufrechterhaltung des circadianen Rhythmus sowie der zeitlichen Steuerung bestimmter Verhaltensweisen. Während die Funktion einiger dieser neuronalen Botenstoffe bereits gut untersucht ist, fehlt sie für andere. Zudem ist noch ungeklärt, wann einzelne Botenstoffe im circadianen Netzwerk agieren. Im Fokus dieser Studie lag daher die Erforschung der Funktion von SIFamide und Corazonin im circadianen Netzwerk sowie die weitere Untersuchung der Funktionen der Neuropeptide MIP und PDF. Es konnte gezeigt werden, dass SIFamide auch in R. maderae in vier großen neurosekretorischen Zellen in der pars intercerebralis exprimiert wird. Varikosenreiche SIFamide-immureaktive (-ir) Fasern innervieren eine Vielzahl an Neuropilen und finden sich auch in der Hüllregion der AME. Injektionsexperimente resultierten in einer monophasischen Phasen-Antwort-Kurve (PRC) mit einer Verzögerung zur frühen subjektiven Nacht. SIFamide ist also ein Eingangssignal für das circadiane Netzwerk und könnte in der Kontrolle der Schalf/Wach-Homöostase involviert sein. Auch Corazonin fungiert als Eingangssignal. Da die Injektionsexperimente in einer monophasischen PRC mit einem Phasenvorschub zur späten subjektiven Nacht resultierten, ist davon auszugehen, dass die Corazonin-ir AME-Zelle Bestandteil des Morning-Oszillator-Netzwerkes in R. maderae ist. Darüber hinaus zeigten Backfill-Experimente, dass MIP an der Kopplung beider AMAE beteiligt ist. ELISA-Quantifizierungen der PDF-Level im Tagesverlauf ergaben Schwankungen in der Konzentration, die auf eine Ausschüttung des Peptids während des Tages hindeuten – ähnlich wie es in Drosophila melanogaster der Fall ist. Dies spiegelt sich in der vervollständigten bimodalen PDF-PRC wieder. Hier führen Injektionen zu einem Phasenvorschub, bevor maximale Peptidlevel erreicht werden, sowie zu einer Phasenverzögerung, sobald die Peptidlevel wieder zu sinken beginnen. Die PRCs erlauben somit Rückschlüsse auf den Zeitpunkt der maximalen Peptidfreisetzung. PDF-ir Neuriten findet sich zudem in sämtlichen Ganglien des ventralen Strickleiternervensystems, was eine Funktion in der Kontrolle der Prozesse impliziert, die durch die Mustergeneratoren in Thorakal- und Abdominalganglien gesteuert werden.

Proyecto María María

María María es un proyecto que se desarrollara en sector de la Joyería y la Bisutería pero con un fuerte enfoque Cultural y artístico. Nuestro producto es más que un accesorio, por un lado es la belleza y distinción que buscan las mujeres y por otro lado es la experiencia del cliente, quien tendrá la oportunidad de personalizar su accesorio, ser diseñador por un rato y lucir su propia creación. Este accesorio pone en contacto al usuario con el mundo literario; es decir con pequeños universos, lleno de múltiples y diversas ideas. En el Siguiente trabajo se plantea un plan de negocios para el desarrollo de Maria Maria, una empresa de diseño de Joyería que se Inspira en la literatura. El objetivo del trabajo es estudiar la situación del sector joyero en Colombia, su viabilidad y crear estrategias para el éxito del mismo para su desarrollo en Colombia y posible expansión a Perú.

Caracterización de las variantes anatómicas de las venas pulmonares en pacientes candidatos a aislamiento de venas pulmonares en Colombia

Introducción y objetivos: El conocimiento de la anatomía de las venas pulmonares y de la aurícula izquierda es fundamental para la planeación y prevención de posibles complicaciones durante la ablación de las venas pulmonares, procedimiento realizado para el manejo de la fibrilación auricular. Este estudio pretende caracterizar la anatomía (tamaño y forma) de las venas pulmonares y determinar las variantes anatómicas más comunes de las mismas. Métodos: Se analizaron 277 estudios de angioresonancia tridimensional y tomografía computarizada realizados previo al procedimiento de aislamiento de venas pulmonares. Se evaluaron los diámetros de la aurícula izquierda, de los ostia de las venas pulmonares y se determinaron la presencia de venas pulmonares comunes, accesorias y ramificaciones tempranas. Resultados: 75% de nuestros pacientes presentaron la anatomía normal de dos venas pulmonares derechas y dos izquierdas. En un 10,1% de los casos se encontraron venas supernumerarias y en un 11,2% se encontró un tronco común. En un 61% de los pacientes se encontraron ramas ostiales, las cuales en un 39,4% de los casos se presentaron en la vena pulmonar inferior derecha. Conclusiones: La evaluación de la morfología de la aurícula derecha y las venas pulmonares por medio de angioresonancia o tomografía computarizada, es necesaria para la realización de ablación por radiofrecuencia dada la alta frecuencia de variantes anatómicas y presencia de ramas ostiales.

Estudi estructural, ultraestructural i histoquímic de les glàndules sexuals accessòries del mascle reproductor porcí (Sus domesticus)

El present treball analitza al microscopi òptic i al microscopi electrònic de transmissió les glàndules sexuals accessòries de Sus domesticus (raça Landrace - varietat anglesa) a partir de mascles reproductors porcins adults i sans. Un millor coneixement dels patrons estructural i ultraestructural normals de las glàndules sexuals accessòries permetrà diagnosticar amb facilitat quina ha estat l'estructura o la funció glandular afectada en mascles en els que s'observa una disminució de la qualitat del semen. Per altra banda, els estudis anatomopatològics s'han de complementar amb tècniques histoquímiques que generalment permeten confirmar o excloure un diagnòstic histopatològic previ. Les glàndules sexuals accessòries del mascle reproductor porcí estan molt desenvolupades i inclouen les glàndules vesiculars, la pròstata i les glàndules bulbouretrals. L'epiteli secretor de les glàndules vesiculars està format per cèl·lules columnars, cèl·lules basals i mastòcits. Les cèl·lules columnars es caracteritzen per presentar tres morfologies diferents que es consideren diferents estadis d'un mateix tipus cel·lular: les cèl·lules principals, les cèl·lules clares i les cèl·lules denses. Les cèl·lules principals secreten activament glicoproteïnes N- i O- glicosilades amb residus d'α-L-fucosa, α(16)fucosa, α-D-mannosa, α-D-glucosa, α- i -D-N-acetilgalactosamina, -D-galactosa-(13)-D-N-acetilgalactosamina, α-D-galactosa, galactosa-(14)-N-acetilglucosamina, D-N-acetilglucosamina i àcid neuramínic. Aquestes glicoproteïnes afavoreixen les interaccions entre l'espermatozoide i l'occit i regulen la permeabilitat de la membrana espermàtica. La pròstata està formada per dues porcions glandulars, el cos de la pròstata (BP) y la pròstata disseminada (DP), entre las quals s'observen diferencies estructurals, ultraestructurals, histoquímiques i funcionals. En ambdues porcions, l'epiteli secretor està constituït per cèl·lules columnars principals, denses i cèl·lules basals, i també per cèl·lules cúbiques en el BP i per cèl·lules mucoses en la DP. En ambdues porcions glandulars, se sintetitzen i secreten N- i O- glicoproteïnes neutres i àcides. Aquestes glicoproteïnes s'alliberen mitjançant un mecanisme regulat en el BP y mitjançant un mecanisme regulat i un constitutiu en la DP. Les glucoproteïnes luminals del BP contenen residus de fucosa, mannosa, α- i -D-N-acetilgalactosamina, galactosa-(14)-N-acetilglucosamina, D-N-acetilglucosamina i àcid neuramínic. En la DP les glicoproteïnes presenten, a més, -D-galactosa-(13)-D-N-acetilgalactosamina i α-D-galactosa. Les glicoproteïnes secretades en el BP i en la DP per via regulada, participen en el control de l'estabilitat del plasmalemma dels espermatozoides, eviten la resposta immune uterina i l'aglutinació dels espermatozoides i afavoreixen la seva motilitat progressiva. Les glicoproteïnes secretades per via constitutiva en la DP protegeixen i lubrifiquen la uretra pelviana. L'epiteli secretor de les glàndules bulbouretrals està format per cèl·lules piramidals principals i denses. Les cèl·lules principals sintetitzen i secreten principalment O-glicoproteïnes àcides carboxilades i sulfatades amb residus glicosídics d'N-acetilgalactosamina, -D-galactosa-(13)-D-N-acetilgalactosamina, α-D-galactosa, D-N-acetilglucosamina i àcid neuramínic. Aquests residus proporcionen resistència a la proteolisi a les O-glicoproteïnes secretades, les quals participen en la lubrificació y protecció de l'epiteli, i intervenen en el control de la permeabilitat del plasmalemma dels espermatozoides i en el transport d'ions al seu través.

Re-evaluating base-metal artefacts: an inscribed lead strap-end from Crewkerne, Somerset

Strap-ends represent the most common class of dress accessory known from late Anglo-Saxon England. At this period, new materials, notably lead and its alloys, were being deployed in the manufacture of personal possessions and jewellery. This newly found strap-end adds to the growing number of tongue-shaped examples fashioned from lead dating from this period. It is, however, distinctive in being inscribed with a personal name. The present article provides an account of the object and its text, and assesses its general significance in the context of a more nuanced interpretation of the social status of lead artefacts in late Anglo-Saxon England.

Spectroscopic imaging of arteries and atherosclerotic plaques

Fourier transform infrared (FTIR) spectroscopic imaging using a focal plane array detector has been used to study atherosclerotic arteries with a spatial resolution of 3-4 mum, i.e., at a level that is comparable with cellular dimensions. Such high spatial resolution is made possible using a micro-attenuated total reflection (ATR) germanium objective with a high refractive index and therefore high numerical aperture. This micro-ATR approach has enabled small structures within the vessel wall to be imaged for the first time by FTIR. Structures observed include the elastic lamellae of the tunica media and a heterogeneous distribution of small clusters of cholesterol esters within an atherosclerotic lesion, which may correspond to foam cells. A macro-ATR imaging method was also applied, which involves the use of a diamond macro-ATR accessory. This study of atherosclerosis is presented as an illustrative example of the wider potential of these A TR imaging approaches for cardiovascular medicine and biomedical applications. (C) 2004 Wiley Periodicals, Inc.

Metabolism of Rhizobium bacteroids

Nitrogen fixation within legume nodules results from a complex metabolic exchange between bacteria of the family Rhizobiaciae and the plant host. Carbon is supplied to the differentiated bacterial cells, termed bacteroids, in the form of dicarboxylic acids to fuel nitrogen fixation. In exchange, fixed nitrogen is transferred to the plant. Both the bacteroid and the plant-derived peribacteroid membrane tightly regulate the exchange of metabolites. In the bacteroid oxidation of dicarboxylic acids via the TCA cycle occurs in an oxygen-limited environment. This restricts the TCA cycle at key points, such as the 2-oxoglutarate dehydrogenase complex, and requires that inputs of carbon and reductant are balanced with outputs from the TCA cycle. This may be achieved by metabolism through accessory pathways that can remove intermediates, reductant, or ATP from the cycle. These include synthesis of the carbon polymers PHB and glycogen and bypass pathways such as the recently identified 2-oxoglutarate decarboxylase reaction in soybean bacteroids. Recent labeling data have shown that bacteroids synthesize and secrete amino acids, which has led to controversy over the role of amino acids in nodule metabolism. Here we review bacteroid carbon metabolism in detail, evaluate the labeling studies that relate to amino acid metabolism by bacteroids, and place the work in context with the genome sequences of Mesorhizobium loti and Sinorhizobium meliloti. We also consider a wider range of metabolic pathways that are probably of great importance to rhizobia in the rhizosphere, during nodule initiation, infection thread development, and bacteroid development.

Cannabinoids stimulate fibroblastic colony formation by bone marrow cells indirectly via CB2 receptors

Recently, the cannabinoid receptors CB1 and CB2 were shown to modulate bone formation and resorption in vivo, although little is known of the mechanisms underlying this. The effects of cannabinoids on mesenchymal stem cell (MSC) recruitment in whole bone marrow were investigated using either the fibroblastic colony-forming unit (CFU-f) assay or high-density cultures of whole bone marrow. Levels of the CB1 and CB2 receptors were assessed by flow cytometry. Treatment of CFU-f cultures with the endocannabinoid 2-arachidonylglycerol (2-AG) dose-dependently increased fibroblastic and differentiated colony formation along with colony size. The nonspecific agonists CP 55,940 and WIN 55,212 both increased colony numbers, as did the CB2 agonists BML190 and JWH015. The CB1-specific agonist ACEA had no effect, whereas the CB2 antagonist AM630 blocked the effect of the natural cannabinoid tetrahydrocannabivarin, confirming mediation via the CB2 receptor. Treatment of primary bone marrow cultures with 2-AG stimulated proliferation and collagen accumulation, whereas treatment of subcultures of MSC had no effect, suggesting that the target cell is not the MSC but an accessory cell present in bone marrow. Subcultures of MSCs were negative for CB1 and CB2 receptors as shown by flow cytometry, whereas whole bone marrow contained a small population of cells positive for both receptors. These data suggest that cannabinoids may stimulate the recruitment of MSCs from the bone marrow indirectly via an accessory cell and mediated via the CB2 receptor. This recruitment may be one mechanism responsible for the increased bone formation seen after cannabinoid treatment in vivo.

Quantitative analysis of mannitol polymorphs: X-ray powder diffractometry—exploring preferred orientation effects

Mannitol is a polymorphic pharmaceutical excipient, which commonly exists in three forms: alpha, beta and delta. Each polymorph has a needle-like morphology, which can give preferred orientation effects when analysed by X-ray powder diffractometry (XRPD) thus providing difficulties for quantitative XRPD assessments. The occurrence of preferred orientation may be demonstrated by sample rotation and the consequent effects on X-ray data can be minimised by reducing the particle size. Using two particle size ranges (less than 125 and 125–500�microns), binary mixtures of beta and delta mannitol were prepared and the delta component was quantified. Samples were assayed in either a static or rotating sampling accessory. Rotation and reducing the particle size range to less than�125 microns halved the limits of detection and quantitation to 1 and 3.6%, respectively. Numerous potential sources of assay errors were investigated; sample packing and mixing errors contributed the greatest source of variation. However, the rotation of samples for both particle size ranges reduced the majority of assay errors examined. This study shows that coupling sample rotation with a particle size reduction minimises preferred orientation effects on assay accuracy, allowing discrimination of two very similar polymorphs at around the 1% level

Purification of coronavirus virions for Cryo-EM and proteomic analysis

Purification of intact enveloped virus particles can be useful as a first step in understanding the structure and function of both viral and host proteins that are incorporated into the virion. Purified preparations of virions can be used to address these questions using techniques such as mass spectrometry proteomics. Recent studies on the proteome of coronavirus virions have shown that in addition to the structural proteins, accessory and non-structural virus proteins and a wide variety of host cell proteins associate with virus particles. To further study the presence of virion proteins, high quality sample preparation is crucial to ensure reproducible analysis by the wide variety of methods available for proteomic analysis.

An intronic G run within HIV-1 intron 2 is critical for splicing regulation of vif mRNA

Within target T lymphocytes, human immunodeficiency virus type I (HIV-1) encounters the retroviral restriction factor APOBEC3G (apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like 3G; A3G), which is counteracted by the HIV-1 accessory protein Vif. Vif is encoded by intron-containing viral RNAs that are generated by splicing at 3' splice site (3'ss) A1 but lack splicing at 5'ss D2, which results in the retention of a large downstream intron. Hence, the extents of activation of 3'ss A1 and repression of D2, respectively, determine the levels of vif mRNA and thus the ability to evade A3G-mediated antiviral effects. The use of 3'ss A1 can be enhanced or repressed by splicing regulatory elements that control the recognition of downstream 5'ss D2. Here we show that an intronic G run (G(I2)-1) represses the use of a second 5'ss, termed D2b, that is embedded within intron 2 and, as determined by RNA deep-sequencing analysis, is normally inefficiently used. Mutations of G(I2)-1 and activation of D2b led to the generation of transcripts coding for Gp41 and Rev protein isoforms but primarily led to considerable upregulation of vif mRNA expression. We further demonstrate, however, that higher levels of Vif protein are actually detrimental to viral replication in A3G-expressing T cell lines but not in A3G-deficient cells. These observations suggest that an appropriate ratio of Vif-to-A3G protein levels is required for optimal virus replication and that part of Vif level regulation is effected by the novel G run identified here.

Ex Vivo Accuracy of an Apex Locator Using Digital Signal Processing in Primary Teeth

The purpose of this study was to evaluate ex vivo the accuracy an electronic apex locator during root canal length determination in primary molars. Methods: One calibrated examiner determined the root canal length in 15 primary molars (total=34 root canals) with different stages of root resorption. Root canal length was measured both visually, with the placement of a K-file 1 mm short of the apical foramen or the apical resorption bevel, and electronically using an electronic apex locator (Digital Signal Processing). Data were analyzed statistically using the intraclass correlation (ICC) test. Results: Comparing the actual and electronic root canal length measurements in the primary teeth showed a high correlation (ICC=0.95) Conclusions: The Digital Signal Processing apex locator is useful and accurate for apex foramen location during root canal length measurement in primary molars. (Pediatr Dent 200937:320-2) Received April 75, 2008 vertical bar Lost Revision August 21, 2008 vertical bar Revision Accepted August 22, 2008

Ex vivo evaluation of the accuracy of two electronic apex locators during root canal length determination in primary teeth

Aim To evaluate ex vivo the accuracy of two electronic apex locators during root canal length determination in primary incisor and molar teeth with different stages of physiological root resorption. Methodology One calibrated examiner determined the root canal length in 17 primary incisors and 16 primary molars (total of 57 root canals) with different stages of root resorption based on the actual canal length and using two electronic apex locators. Root canal length was measured both visually, with the placement of a K-file 1 mm short of the apical foramen or the apical resorption bevel, and electronically using two electronic apex locators (Root ZX II - J. Morita Corp. and Mini Apex Locator - SybronEndo) according to the manufacturers` instructions. Data were analysed statistically using the intraclass correlation (ICC) test. Results Comparison of the actual root canal length and the electronic root canal length measurements revealed high correlation (ICC = 0.99), regardless of the tooth type (single-rooted and multi-rooted teeth) or the presence/absence of physiological root resorption. Conclusions Root ZX II and Mini Apex Locator proved useful and accurate for apex foramen location during root canal length measurement in primary incisors and molars.

Accuracy of the iPex multi-frequency electronic apex locator in primary molars: an ex vivo study

P>Aim To evaluate ex vivo the accuracy of the iPex multi-frequency electronic apex locator (NSK Ltd, Tokyo, Japan) for working length determination in primary molar teeth. Methodology One calibrated examiner determined the working length in 20 primary molar teeth (total of 33 root canals). Working length was measured both visually, with the placement of a K-file 1 mm short of the apical foramen or the most coronal limit of root resorption, and electronically using the electronic apex locator iPex, according to the manufacturers` instructions. Data were analysed statistically using the intraclass correlation (ICC) test. Results Comparison of the actual and the electronic measurements revealed high correlation (ICC = 0.99) between the methods, regardless of the presence or absence of physiological root resorption. Conclusions In this laboratory study, the iPex accurately identified the apical foramen or the apical opening location for working length measurement in primary molar teeth.

Correlation between citric acid and nitrate metabolisms during CAM cycle in the atmospheric bromeliad Tillandsia pohliana

Crassulacean acid metabolism (CAM) confers crucial adaptations for plants living under frequent environmental stresses. A wide metabolic plasticity can be found among CAM species regarding the type of storage carbohydrate, organic acid accumulated at night and decarboxylating system. Consequently, many aspects of the CAM pathway control are still elusive while the impact of this photosynthetic adaptation on nitrogen metabolism has remained largely unexplored. In this study, we investigated a possible link between the CAM cycle and the nitrogen assimilation in the atmospheric bromeliad Tillandsia pohliana by simultaneously characterizing the diel changes in key enzyme activities and metabolite levels of both organic acid and nitrate metabolisms. The results revealed that T. pohliana performed a typical CAM cycle in which phosphoenolpyruvate carboxylase and phosphoenolpyruvate carboxykinase phosphorylation seemed to play a crucial role to avoid futile cycles of carboxylation and decarboxylation. Unlike all other bromeliads previously investigated, almost equimolar concentrations of malate and citrate were accumulated at night. Moreover, a marked nocturnal depletion in the starch reservoirs and an atypical pattern of nitrate reduction restricted to the nighttime were also observed. Since reduction and assimilation of nitrate requires a massive supply of reducing power and energy and considering that T. pohliana lives overexposed to the sunlight, we hypothesize that citrate decarboxylation might be an accessory mechanism to increase internal CO(2) concentration during the day while its biosynthesis could provide NADH and ATP for nocturnal assimilation of nitrate. Therefore, besides delivering photoprotection during the day, citrate might represent a key component connecting both CAM pathway and nitrogen metabolism in T. pohliana: a scenario that certainly deserves further study not only in this species but also in other CAM plants that nocturnally accumulate citrate. (C) 2010 Elsevier GmbH. All rights reserved.