A zinc transporter gene required for development of the nervous system.

The essentiality of zinc for normal brain development is well established. It has been suggested that primary and secondary zinc deficiencies can contribute to the occurrence of numerous human birth defects, including many involving the central nervous system. In a recent study, we searched for zinc transporter genes that were critical for neurodevelopment. We confirmed that ZIP12 is a zinc transporter encoded by the gene slc39a12 that is highly expressed in the central nervous systems of human, mouse, and frog (Xenopus tropicalis).Using loss-of-function methods, we determined that ZIP12 is required for neuronal differentiation and neurite outgrowth and necessary for neurulation and embryonic viability. These results highlight an essential need for zinc regulation during embryogenesis and nervous system development. We suggest that slc39a12 is a candidate gene for inherited neurodevelopmental defects in humans

Mineralogy of Tongue of the ocean sediments

The carbonate mineralogy of 25 short cores from the Tongue of the Ocean has been determined. Evidence presented in this paper indicates that carbonate mineralogy may reflect Pleistocene sea-level changes due to an increased contribution of low magnesium calcite from the subaerially exposed Bahama Banks when sea levels were low. It is suggested that this relationship of mineralogy to sea level may find wide application in the study of carbonate sedimentation in intermediate-depth water, proximal to carbonate banks

Elastin metabolism and chemistry: potential roles in lung development and structure.

Elastic fibers are important for elasticity and extensibility of lung tissue. In the developing lung, elastic fibers appear in greatest numbers during the process or period of alveolarization . A variety of mesenchymal cells in lung appear responsible for elastin synthesis. Elastin is a novel protein both from the standpoint of its processing into elastic fibers and chemical properties. For example, elastin undergoes posttranslational modification before its assembly into fibers. These steps include limited proteolysis, hydroxylation of prolyl residues and the oxidative deamination of lysyl residues prior to their incorporation into the crosslinks that covalently bond together polypeptide chains of elastin. The crosslinking amino acids include lysinonorleucine , merodesmosine and desmosine isomers. A key enzyme that controls this process is lysyl oxidase. Lysyl oxidase is a copper metalloprotein whose activity is responsive to and modulated by environmental insults, nutrition deficiencies and the administration of various pharmacological agents. Regarding chemical properties, elastin is one of the most apolar proteins secreted by mammalian cells. Moreover, elastin is one of the most long-lived proteins secreted into the extracellular matrix. In relationship to its processing into elastic fibers and chemical properties, details related to major aspects of elastin metabolism as well as speculation on its potential as a factor in lung development and disease are discussed

In-flight calibration of STEREO-B/WAVES antenna system

The STEREO/WAVES (SWAVES) experiment on board the two STEREO spacecraft (Solar Terrestrial Relations Observatory) launched on 25 October 2006 is dedicated to the measurement of the radio spectrum at frequencies between a few kilohertz and 16 MHz. The SWAVES antenna system consists of 6 m long orthogonal monopoles designed to measure the electric component of the radio waves. With this configuration direction finding of radio sources and polarimetry (analysis of the polarization state) of incident radio waves is possible. For the evaluation of the SWAVES data the receiving properties of the antennas, distorted by the radiation coupling with the spacecraft body and other onboard devices, have to be known accurately. In the present context, these properties are described by the antenna effective length vectors. We present the results of an in-flight calibration of the SWAVES antennas using the observations of the nonthermal terrestrial auroral kilometric radiation (AKR) during STEREO roll maneuvers in an early stage of the mission. A least squares method combined with a genetic algorithm was applied to find the effective length vectors of the STEREO Behind (STEREO-B)/WAVES antennas in a quasi-static frequency range ($L_{antenna} \ll \lambda_{wave}$) which fit best to the model and observed AKR intensity profiles. The obtained results confirm the former SWAVES antenna analysis by rheometry and numerical simulations. A final set of antenna parameters is recommended as a basis for evaluations of the SWAVES data

Targeted Derepression of the Human Immunodeficiency Virus Type 1 Long Terminal Repeat by Pyrrole-Imidazole Polyamides

The host factor LSF represses the human immunodeficiency virus type 1 long terminal repeat (LTR) by mediating recruitment of histone deacetylase. We show that pyrrole-imidazole polyamides targeted to the LTR can specifically block LSF binding both in vitro and within cells via direct access to chromatin, resulting in increased LTR expression

The Effect of the GATT on U.S. Peanut Markets

The Uruguay Round of the General Agreement on Tariffs and Trade (hereafter, the GATT), which is to be signed by more than 10 nations on December 15, 1993, represents the culmination of seven years of negotiations on reforms of international trade. Assuming that the U.S. Congress will ratify the agreement, most, if not all, agricultural commodities produced in the United States will be affected in some way. The purpose of the present paper is to examine the likely effects of the GATT on U.S. peanut markets. Although the market value of U.S. peanut production is small compared to many other U.S. agricultural commodities, the impacts of the GATT on peanut markets are of considerable interest for at least two reasons

Perioperatives Management und Immunsuppression bei xenogener orthotoper Herztransplantation im Schwein - Primaten - Modell

Herztransplantationen stellen die Therapie der Wahl bei irreversiblen, terminalen Herzerkrankungen dar. Im Moment kommen bei dieser Indikationsstellung in erster Linie Transplantate von hirntoten Spendern, d.h. allogene Transplantate, zur Anwendung. Bei entsprechender Compliance erreichen die Patienten postoperativ eine erhebliche körperliche Belastbarkeit und Lebensqualität. Die Fragestellung der Untersuchungen am Institut für Chirurgische Forschung war, ob nach Immunadsorption bei Xenotransplantation von Herzen transgener Schweine, die human decay accelerating factor (hDAF) exprimieren, ein besseres Langzeitüberleben von Pavianen zu beobachten ist als in entsprechenden Vergleichsgruppen

Sequence specific fluorescence detection of double strand DNA

Methods for the fluorescent detection of specific sequences of double strand DNA in homogeneous solution may be useful in the field of human genetics. A series of hairpin polyamides with tetramethyl rhodamine (TMR) attached to an internal pyrrole ring were synthesized, and the fluorescence properties of the polyamide-fluorophore conjugates in the presence and absence of duplex DNA were examined. We observe weak TMR fluorescence in the absence of DNA. Addition of ≥ 1:1 match DNA affords a significant fluorescence increase over equimolar mismatch DNA for each polyamide-TMR conjugate. Polyamide-fluorophore conjugates offer a new class of sensors for the detection of specific DNA sequences without the need for denaturation. The polyamide-dye fluorescence-based method can be used to screen in parallel the interactions between aromatic ring pairs and the minor groove of DNA even when the binding site contains a non-Watson-Crick DNA base pair. A ranking of the specificity of three polyamide ring pairs-Py/Py, Im/Py, and Im/Im-was established for all 16 possible base pairs of A, T, G, and C in the minor groove. We find that Im/Im is an energetically favorable ring pair for minor groove recognition of the T·G base pair