123 research outputs found
Cattle Mammary Bioreactor Generated by a Novel Procedure of Transgenic Cloning for Large-Scale Production of Functional Human Lactoferrin
Large-scale production of biopharmaceuticals by current bioreactor techniques is limited by low transgenic efficiency and low expression of foreign proteins. In general, a bacterial artificial chromosome (BAC) harboring most regulatory elements is capable of overcoming the limitations, but transferring BAC into donor cells is difficult. We describe here the use of cattle mammary bioreactor to produce functional recombinant human lactoferrin (rhLF) by a novel procedure of transgenic cloning, which employs microinjection to generate transgenic somatic cells as donor cells. Bovine fibroblast cells were co-microinjected for the first time with a 150-kb BAC carrying the human lactoferrin gene and a marker gene. The resulting transfection efficiency of up to 15.79×10−2 percent was notably higher than that of electroporation and lipofection. Following somatic cell nuclear transfer, we obtained two transgenic cows that secreted rhLF at high levels, 2.5 g/l and 3.4 g/l, respectively. The rhLF had a similar pattern of glycosylation and proteolytic susceptibility as the natural human counterpart. Biochemical analysis revealed that the iron-binding and releasing properties of rhLF were identical to that of native hLF. Importantly, an antibacterial experiment further demonstrated that rhLF was functional. Our results indicate that co-microinjection with a BAC and a marker gene into donor cells for somatic cell cloning indeed improves transgenic efficiency. Moreover, the cattle mammary bioreactors generated with this novel procedure produce functional rhLF on an industrial scale
Examining the effects of social media in co-located classrooms: A case study based on SpeakUp
The broad availability of mobile computing devices has prompted the apparition of social media applications that support teaching and learning. However, so far, there is conflicting evidence as to whether the benefits such applications provide in terms of engagement and interaction, outweigh their potential cost as a source of distraction. To help in clarifying these issues, the present paper presents a case study on the impact of using SpeakUp (an app aimed at promoting student participation through anonymous chatrooms) in an authentic face-to-face learning scenario. Concretely, we focus on the connection between SpeakUp and the student engagement, distraction, social interaction, and the influence of the teachers' style. Our findings highlight that SpeakUp favored students' engagement and social interaction, but they also point towards its limitations in keeping students communicating about content relevant to the course
Structure of photosynthetic LH1-RC supercomplex at 1.9 Å resolution
Light-harvesting complex 1 (LH1) and the reaction centre (RC) form a membrane-protein supercomplex that performs the primary reactions of photosynthesis in purple photosynthetic bacteria. The structure of the LH1-RC complex can provide information on the arrangement of protein subunits and cofactors; however, so far it has been resolved only at a relatively low resolution. Here we report the crystal structure of the calcium-ion-bound LH1-RC supercomplex of Thermochromatium tepidum at a resolution of 1.9 Å. This atomic-resolution structure revealed several new features about the organization of protein subunits and cofactors. We describe the loop regions of RC in their intact states, the interaction of these loop regions with the LH1 subunits, the exchange route for the bound quinone QB with free quinone molecules, the transport of free quinones between the inside and outside of the LH1 ring structure, and the detailed calcium-ion-binding environment. This structure provides a solid basis for the detailed examination of the light reactions that occur during bacterial photosynthesis
Sensitivity of the T2K accelerator-based neutrino experiment with an Extended run to POT
18 pages, 4 figures18 pages, 4 figures18 pages, 4 figures18 pages, 4 figures18 pages, 4 figuresRecent measurements at the T2K experiment indicate that CP violation in neutrino mixing may be observed in the future by long-baseline neutrino oscillation experiments. We explore the physics program of an extension to the currently approved T2K running of protons-on-target to protons-on-target,aiming at initial observation of CP violation with 3 or higher significance for the case of maximum CP violation. With accelerator and beam line upgrades, as well as analysis improvements, this program would occur before the next generation of long-baseline neutrino oscillation experiments that are expected to start operation in 2026.We acknowledge the support of MEXT, Japan; NSERC (Grant No. SAPPJ-2014-00031), NRC and CFI, Canada; CEA and CNRS/IN2P3, France; DFG, Germany; INFN, Italy; National Science Centre (NCN), Poland; RSF, RFBR and MES, Russia; MINECO and ERDF funds, Spain; SNSF and SERI, Switzerland; STFC, UK; and DOE, USA. We also thank CERN for the UA1/NOMAD magnet, DESY for the HERA-B magnet mover system, NII for SINET4, the WestGrid and SciNet consortia in Compute Canada, and GridPP in the United Kingdom. In addition, participation of individual researchers and institutions has been further supported by funds from ERC (FP7), H2020 Grant No. RISE-GA644294-JENNIFER, EU; JSPS, Japan; Royal Society, UK; and the DOE Early Career program, USA. CNRS/IN2P3: Centre National de la Recherche ScientifiqueInstitut National de Physique Nucleaire et de Physique des Particules RSF: Russian Science Foundation MES: Ministry of Education and Science, Russia ERDF: European Regional Development Fund SNSF: Swiss National Science Foundation SER (should be SERI): State Secretariat for Education, Research and Innovatio
Proposal for an Extended Run of T2K to POT
68 pages, 31 figures68 pages, 31 figures68 pages, 31 figuresRecent measurements by the T2K neutrino oscillation experiment indicate that CP violation in neutrino mixing may be observed in the future by long-baseline neutrino oscillation experiments. We propose an extension to the currently approved T2K running from 7.8\times 10^{21}~\mbox{POT} to 20\times 10^{21}~\mbox{POT}, aiming at initial observation of CP violation with 3 or higher significance for the case of maximum CP violation. The program also contains a measurement of mixing parameters, and , with a precision of 1.7 or better and 1%, respectively. With accelerator and beamline upgrades, as well as analysis improvements, this program would occur before the next generation of long-baseline neutrino oscillation experiments that are expected to start operation in 2026
Clinical Use and Therapeutic Potential of IVIG/SCIG, Plasma-Derived IgA or IgM, and Other Alternative Immunoglobulin Preparations
Intravenous and subcutaneous immunoglobulin preparations, consisting of IgG class antibodies, are increasingly used to treat a broad range of pathological conditions, including humoral immune deficiencies, as well as acute and chronic inflammatory or autoimmune disorders. A plethora of Fab- or Fc-mediated immune regulatory mechanisms has been described that might act separately or in concert, depending on pathogenesis or stage of clinical condition. Attempts have been undertaken to improve the efficacy of polyclonal IgG preparations, including the identification of relevant subfractions, mild chemical modification of molecules, or modification of carbohydrate side chains. Furthermore, plasma-derived IgA or IgM preparations may exhibit characteristics that might be exploited therapeutically. The need for improved treatment strategies without increase in plasma demand is a goal and might be achieved by more optimal use of plasma-derived proteins, including the IgA and the IgM fractions. This article provides an overview on the current knowledge and future strategies to improve the efficacy of regular IgG preparations and discusses the potential of human plasma-derived IgA, IgM, and preparations composed of mixtures of IgG, IgA, and IgM
Measurement of the single pi(0) production rate in neutral current neutrino interactions on water
The single π0 production rate in neutral current neutrino interactions on water in a neutrino beam with a peak neutrino energy of 0.6 GeV has been measured using the PØD, one of the subdetectors of the T2K near detector. The production rate was measured for data taking periods when the PØD contained water (2.64×10(20) protons-on-target) and also periods without water (3.49×10(20) protons-on-target). A measurement of the neutral current single π0 production rate on water is made using appropriate subtraction of the production rate with water in from the rate with water out of the target region. The subtraction analysis yields 106 ± 41 ± 69 signal events where the uncertainties are statistical (stat.) and systematic (sys.) respectively. This is consistent with the prediction of 157 events from the nominal simulation. The measured to expected ratio is 0.68 ± 0.26 (stat) ± 0.44 (sys) ± 0.12 (flux). The nominal simulation uses a flux integrated cross section of 7.63×10(−39)cm(2) per nucleon with an average neutrino interaction energy of 1.3 GeV
First Measurement of the Muon Neutrino Charged Current Single Pion Production Cross Section on Water with the T2K Near Detector
The T2K off-axis near detector, ND280, is used to make the first differential cross section measurements of muon neutrino charged current single positive pion production on a water target at energies GeV. The differential measurements are presented as a function of muon and pion kinematics, in the restricted phase-space defined by MeV/c, MeV/c, and . The total flux integrated charged current single positive pion production cross section on water in the restricted phase-space is measured to be . The total cross section is consistent with the NEUT prediction () and 2 lower than the GENIE prediction (). The differential cross sections are in good agreement with the NEUT generator. The GENIE simulation reproduces well the shapes of the distributions, but over-estimates the overall cross section normalization
Characterization of nuclear effects in muon-neutrino scattering on hydrocarbon with a measurement of final-state kinematics and correlations in charged-current pionless interactions at T2K
This paper reports measurements of final-state proton multiplicity, muon and proton kinematics, and
their correlations in charged-current pionless neutrino interactions, measured by the T2K ND280 near
detector in its plastic scintillator (C8H8) target. The data were taken between years 2010 and 2013,
corresponding to approximately 6 × 1020 protons on target. Thanks to their exploration of the proton
kinematics and of imbalances between the proton and muon kinematics, the results offer a novel probe of
the nuclear-medium effects most pertinent to the (sub-)GeV neutrino-nucleus interactions that are used in
accelerator-based long-baseline neutrino oscillation measurements. These results are compared to many
neutrino-nucleus interaction models which all fail to describe at least part of the observed phase space.
In case of events without a proton above a detection threshold in the final state, a fully consistent
implementation of the local Fermi gas model with multinucleon interactions gives the best description of
the data. In the case of at least one proton in the final state, the spectral function model agrees well with the
data, most notably when measuring the kinematic imbalance between the muon and the proton in the plane
transverse to the incoming neutrino. Within the models considered, only the existence of multinucleon
interactions are able to describe the extracted cross section within regions of high transverse kinematic
imbalance. The effect of final-state interactions is also discussed
- …