Search results for "Replication"
showing 10 items of 489 documents
The nucleosomal repeat length of pea (Pisum sativum) chromatin changes during germination
1985
Pea (Pisum sativum) nuclei have been isolated from ungerminated embryos, developing embryonic axes and seedlings. Morphological and biochemical criteria revealed that preparations were free from contaminants and that nuclei were intact. These circumstances permitted an accurate determination of nucleosomal repeat lengths, the values obtained being 175±4 base pairs for ungerminated embryos, 185±5 base pairs for 62-hours germinated embryonic axes and 185±3 base pairs for 6-day old seedlings. The results seem to indicate that the increase in repeat length is associated with the onset of transcription and/or replication of DNA.
(2'-5')Oligoadenylate and intracellular immunity against retrovirus infection.
1992
1. 1. The double-stranded RNA-dependent 2′,5′-oligoadenylate (2–5A) synthetase/ribonuclease L (RNase L) system plays an essential role in the establishment of the antiviral state of a cell exposed to virus infection. 2. 2. Until recently, the application of 2–5A derivatives to reinforce this system seemed to be limited mainly due to the low specificity of RNase L for viral RNA. 3. 3. Two new strategies have been developed which yield a selective antiviral effect of 2–5As at least against human immunodeficiency virus-1 (HIV-1) infection: (i) an “intracellular immunization” appproach using 2-5A synthetase cDNA linked to HIV trans -acting response element (TAR) and (ii) inhibition of retrovira…
An Agenda for Open Science in Communication
2021
Contains fulltext : 226720.pdf (Publisher’s version ) (Open Access) In the last 10 years, many canonical findings in the social sciences appear unreliable. This so-called "replication crisis" has spurred calls for open science practices, which aim to increase the reproducibility, replicability, and generalizability of findings. Communication research is subject to many of the same challenges that have caused low replicability in other fields. As a result, we propose an agenda for adopting open science practices in Communication, which includes the following seven suggestions: (1) publish materials, data, and code; (2) preregister studies and submit registered reports; (3) conduct replicatio…
Promoting scientific integrity through open science in health psychology: results of the Synergy Expert Meeting of the European health psychology soc…
2021
The current article describes a position statement and recommendations for actions that need to be taken to develop best practices for promoting scientific integrity through open science in health psychology endorsed at a Synergy Expert Group Meeting. Sixteen Synergy Meeting participants specializing in health, social and behavioural psychology convened to discuss priority issues regarding scientific integrity promotion and open science in health psychology. The group developed a set of recommendations for researchers, gatekeepers, and research end-users. The group process followed a nominal group technique and voting system to elicit and decide on the most relevant and topical issues. Seve…
Molecular Characterization of the Leucine Plasmid from Buchnera aphidicola , Primary Endosymbiont of the Aphid Acyrthosiphon pisum
2000
The complete sequence of the leucine plasmid of Buchnera aphidicola from the aphid Acyrthosiphon pisum (pLeu-BAp) is reported. Its gene organization was concordant with those of other leucine plasmids of Buchnera from aphids of the Aphidini and Macrosiphini tribes. Three inverted repeats are present in pLeu-BAp. Two of them are also present in pLeu from the family Aphididae: (i) SIR1, located downstream the leucine operon, resembles a rho-independent terminator of transcription, and (ii) LIR1, located upstream of the leucine operon, is suggested to be involved in transcription termination or messenger stability. The third, located near the putative ATGC repeats involved in the origin of rep…
Amino acids requirements of measles virus in HeLa cells.
1973
A low plating efficiency for measles virus was obtained when arginine, threonine and isoleucine were omitted from Eagle's basal medium and a stimulatory effect on the plaque production was produced by increasing the concentration up to 0.5 mm of arginine and glutamine. However, of all amino acids in Eagle's basal medium, only methionine was found to be essential for the synthesis of infectious progeny virus. Omission of any one of the other amino acids from the culture medium permitted limited virus production, but none whatever could be detected in the absence of mediummethionine. Moreover, when methionine was restored to infected cultures after 24 hours of deprivation, release of virus be…
Parvovirus induced alterations in nuclear architecture and dynamics.
2009
The nucleus of interphase eukaryotic cell is a highly compartmentalized structure containing the three-dimensional network of chromatin and numerous proteinaceous subcompartments. DNA viruses induce profound changes in the intranuclear structures of their host cells. We are applying a combination of confocal imaging including photobleaching microscopy and computational methods to analyze the modifications of nuclear architecture and dynamics in parvovirus infected cells. Upon canine parvovirus infection, expansion of the viral replication compartment is accompanied by chromatin marginalization to the vicinity of the nuclear membrane. Dextran microinjection and fluorescence recovery after ph…
HSV hepatitis in the mouse: A light and electron microscopic study with immunohistology and in situ hybridization
1988
In order to characterize better the morphology and immune response in acute necrotizing HSV infection, murine HSV hepatitis was examined. BALB/c mice were inoculated intraperitoneally with 10(6) plaque-forming units (PFU) of HSV-1 (Lenette) and HSV-2 (D316). In both groups half the animals were pretreated with silica particles to block macrophage function. Up to 6 days after infection four mice from each group were sacrificed at daily intervals and the livers were examined by light and electron microscopy, immunohistology, in situ hybridization, combined immunohistology/in situ hybridization and titration of viral PFU. HSV-2 infected mice developed severe necrotizing hepatitis with persiste…
Role of mitochondria in parvovirus pathology.
2014
Proper functioning of the mitochondria is crucial for the survival of the cell. Viruses are able to interfere with mitochondrial functions as they infect the host cell. Parvoviruses are known to induce apoptosis in infected cells, but the role of the mitochondria in parvovirus induced cytopathy is only partially known. Here we demonstrate with confocal and electron microscopy that canine parvovirus (CPV) associated with the mitochondrial outer membrane from the onset of infection. During viral entry a transient depolarization of the mitochondrial transmembrane potential and increase in ROS level was detected. Subsequently, mitochondrial homeostasis was normalized shortly, as detected by rep…
Inactivation of an Enveloped Virus by Immobilized Antimicrobial Peptides.
2021
Infections caused by viruses are difficult to treat due to their life cycle, which depends on the replication machinery of the respective host cells. Commonly used antiviral strategies are based upon the application of, e.g., entry inhibitors and other compounds that interfere with virus replication. Besides possible side effects, the rapid occurrence of viral resistance poses a great challenge. Antimicrobial peptides (AMPs), as a component of the innate immunity, are able to kill bacteria and fungi and, in addition, may inactivate enveloped viruses. Many AMPs exert their biological function by impairing microbial and viral membranes. As a result, membrane integrity is lost, leading to bact…