scholarly journals Angicin, a novel bacteriocin of Streptococcus anginosus

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Verena Vogel ◽  
Richard Bauer ◽  
Stefanie Mauerer ◽  
Nicole Schiffelholz ◽  
Christian Haupt ◽  
...  
Keyword(s):  
Defense Mechanism ◽  
Food Preservation ◽  
Target Cells ◽  
Clinical Settings ◽  
Pathogenic Potential ◽  
Streptococcus Anginosus ◽  
Bacteriocin Producer ◽  
Potential Applications ◽  
Interesting Compound ◽  
High Pathogenic

AbstractAs a conserved defense mechanism, many bacteria produce antimicrobial peptides, called bacteriocins, which provide a colonization advantage in a multispecies environment. Here the first bacteriocin of Streptococcus anginosus, designated Angicin, is described. S. anginosus is commonly described as a commensal, however it also possesses a high pathogenic potential. Therefore, understanding factors contributing to its host colonization and persistence are important. A radial diffusion assay was used to identify S. anginosus BSU 1211 as a potent bacteriocin producer. By genetic mutagenesis the background of bacteriocin production and the bacteriocin gene itself were identified. Synthetic Angicin shows high activity against closely related streptococci, listeria and vancomycin resistant enterococci. It has a fast mechanism of action and causes a membrane disruption in target cells. Angicin, present in cell free supernatant, is insensitive to changes in temperature from − 70 to 90 °C and pH values from 2 to 10, suggesting that it represents an interesting compound for potential applications in food preservation or clinical settings.

scholarly journals Angicin, a novel bacteriocin of Streptococcus anginosus

2021 ◽  
Author(s):  
Verena Vogel ◽  
Richard Bauer ◽  
Stefanie Mauerer ◽  
Nicole Schiffelholz ◽  
Christian Haupt ◽  
...  
Keyword(s):  
Defense Mechanism ◽  
Food Preservation ◽  
Target Cells ◽  
Clinical Settings ◽  
Pathogenic Potential ◽  
Streptococcus Anginosus ◽  
Bacteriocin Producer ◽  
Potential Applications ◽  
Interesting Compound ◽  
High Pathogenic

AbstractAs a conserved defense mechanism, many bacteria produce antimicrobial peptides, called bacteriocins, which give a colonization advantage in a multispecies environment. Here the first bacteriocin of Streptococcus anginosus, designated Angicin, is described. S. anginosus is commonly described as a commensal, however it also possesses a high pathogenic potential. Therefore, understanding factors contributing to its host colonization and persistence are important. A radial diffusion assay was used to identify S. anginosus BSU 1211 as a potent bacteriocin producer. By genetic mutagenesis the background of bacteriocin production and the bacteriocin gene itself were identified. Synthetic Angicin shows high activity against closely related streptococci, listeria and vancomycin resistant enterococci. It has a fast mechanism of action and causes a membrane disruption in target cells. Angicin, present in cell free supernatant, is insensitive to changes in temperature from −70 to 90 °C and pH values from 2-10, suggesting that it represents an interesting compound for potential applications in food preservation or clinical settings.

scholarly journals Evidence of Human Parvovirus B19 Infection in the Post-Mortem Brain Tissue of the Elderly

Viruses ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 582 ◽  
Author(s):  
Sandra Skuja ◽  
Anda Vilmane ◽  
Simons Svirskis ◽  
Valerija Groma ◽  
Modra Murovska
Keyword(s):  
White Matter ◽  
Frontal Lobe ◽  
Brain Tissue ◽  
Morphological Changes ◽  
Structural Characteristics ◽  
Parvovirus B19 ◽  
Elderly Subjects ◽  
Target Cells ◽  
Human Parvovirus B19 ◽  
Pathogenic Potential

After primary exposure, the human parvovirus B19 (B19V) genome may remain in the central nervous system (CNS), establishing a lifelong latency. The structural characteristics and functions of the infected cells are essential for the virus to complete its life cycle. Although B19V has been detected in the brain tissue by sequencing PCR products, little is known about its in vivo cell tropism and pathogenic potential in the CNS. To detect B19V and investigate the distribution of its target cells in the CNS, we studied brain autopsies of elderly subjects using molecular virology, and optical and electron microscopy methods. Our study detected B19V in brain tissue samples from both encephalopathy and control groups, suggesting virus persistence within the CNS throughout the host’s lifetime. It appears that within the CNS, the main target of B19V is oligodendrocytes. The greatest number of B19V-positive oligodendrocytes was found in the white matter of the frontal lobe. The number was significantly lower in the gray matter of the frontal lobe (p = 0.008) and the gray and white matter of the temporal lobes (p < 0.0001). The morphological changes observed in the encephalopathy group, propose a possible B19V involvement in the demyelination process.

scholarly journals Plate reader microrheology

2020 ◽  
Author(s):  
Robert F. Hawkins ◽  
Gregg A. Duncan
Keyword(s):  
Particle Tracking ◽  
Fluorescence Polarization ◽  
Rotational Diffusion ◽  
Polymeric Materials ◽  
Soft Materials ◽  
Clinical Samples ◽  
Clinical Settings ◽  
Particle Tracking Microrheology ◽  
Plate Reader ◽  
Potential Applications

AbstractIn this work, we report the development of a simplified microrheological method that can be used to rapidly study soft materials. This approach uses fluorescence polarization and a plate reader format to measure the rotational diffusion of nanoparticles within a sample of interest. We show that this measurement is sensitive to viscosity-dependent changes in polymeric soft materials and is correlated with particle tracking microrheology, a previously validated measure of microrheology. Using these fluorescence polarization-based measurements, we describe formalism that enables reasonable estimation of viscosity in polymeric materials after accounting for length-scale dependent effects of the polymer environment on the nanoparticle rotational diffusion. The use of a plate reader format allows this approach to be higher throughput, less technically challenging, and more widely accessible than standard macro- and microrheological methods, making it available to non-experts. This approach has potential applications in academic and industry settings where conventional rheological equipment may not be available, as well as in clinical settings to rapidly characterize human clinical samples.

scholarly journals CD8+ T Lymphocytes Mediate Borna Disease Virus-Induced Immunopathology Independently of Perforin

2001 ◽  
Vol 75 (21) ◽  
pp. 10460-10466 ◽  
Author(s):  
Jürgen Hausmann ◽  
Karin Schamel ◽  
Peter Staeheli
Keyword(s):  
T Cells ◽  
T Lymphocytes ◽  
Disease Virus ◽  
Target Cells ◽  
Wild Type ◽  
Pathogenic Potential ◽  
Borna Disease Virus ◽  
Viral Spread ◽  
Deficient Mice ◽  
Borna Disease

ABSTRACT Perforin-mediated lysis of target cells is the major antiviral effector mechanism of CD8+ T lymphocytes. We have analyzed the role of perforin in a mouse model for CD8+T-cell-mediated central nervous system (CNS) immunopathology induced by Borna disease virus. When a defective perforin gene was introduced into the genetic background of the Borna disease-susceptible mouse strain MRL, the resulting perforin-deficient mice developed strong neurological disease in response to infection indistinguishable from that of their perforin-expressing littermates. The onset of disease was slightly delayed. Brains of diseased perforin-deficient mice showed similar amounts and a similar distribution of CD8+ T cells as wild-type animals. Perforin deficiency had no impact on the kinetics of viral spread through the CNS. Unlike brain lymphocytes from diseased wild-type mice, lymphocytes from perforin-deficient MRL mice showed no in vitro cytolytic activity towards target cells expressing the nucleoprotein of Borna disease virus. Taken together, these results demonstrate that CD8+ T cells mediate Borna disease independent of perforin. They further suggest that the pathogenic potential of CNS-infiltrating CD8+ T cells does not primarily reside in their lytic activity but rather in other functions.

Molecular Mechanisms of Renal Ischemic Conditioning Strategies

2015 ◽  
Vol 55 (3) ◽  
pp. 151-183 ◽  
Author(s):  
Casper Kierulf-Lassen ◽  
Gertrude J. Nieuwenhuijs-Moeke ◽  
Nicoline V. Krogstrup ◽  
Mihai Oltean ◽  
Bente Jespersen ◽  
...  
Keyword(s):  
Reperfusion Injury ◽  
Molecular Mechanisms ◽  
Defense Mechanism ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Kidney Injury ◽  
Clinical Settings ◽  
Ischemic Conditioning ◽  
Protective Signaling ◽  
Survival Mechanisms

Ischemia-reperfusion injury is the leading cause of acute kidney injury in a variety of clinical settings such as renal transplantation and hypovolemic and/or septic shock. Strategies to reduce ischemia-reperfusion injury are obviously clinically relevant. Ischemic conditioning is an inherent part of the renal defense mechanism against ischemia and can be triggered by short periods of intermittent ischemia and reperfusion. Understanding the signaling transduction pathways of renal ischemic conditioning can promote further clinical translation and pharmacological advancements in this era. This review summarizes research on the molecular mechanisms underlying both local and remote ischemic pre-, per- and postconditioning of the kidney. The different types of conditioning strategies in the kidney recruit similar powerful pro-survival mechanisms. Likewise, renal ischemic conditioning mobilizes many of the same protective signaling pathways as in other organs, but differences are recognized.

scholarly journals Hormographiella aspergillata: an emerging basidiomycete in the clinical setting? A case report and literature review

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Maxime Moniot ◽  
Rose-Anne Lavergne ◽  
Thomas Morel ◽  
Romain Guieze ◽  
Florent Morio ◽  
...  
Keyword(s):  
Antifungal Susceptibility ◽  
Diagnostic Tools ◽  
Clinical Settings ◽  
Invasive Infection ◽  
Pathogenic Potential ◽  
Short Period ◽  
Invasive Infections ◽  
In Vitro Antifungal Susceptibility ◽  
First Time

Abstract Background Filamentous basidiomycetes are mainly considered to be respiratory tract colonizers but the clinical significance of their isolation in a specimen is debatable. Hormographiella aspergillata was first reported as a human pathogen in 1971. We discuss the role of this mold as a pathogen or colonizer and give an update on diagnostic tools and in vitro antifungal susceptibility. Case presentation We identified three cases of H. aspergillata with respiratory symptoms in a short period of time. One invasive infection and two colonizations were diagnosed. Culture supernatants showed that H. aspergillata can produce galactomannan and β-D-glucan but not glucuronoxylomannan. For the first time, isavuconazole susceptibility was determined and high minimum inhibitory concentrations (MICs) were found. Liposomal amphotericin B and voriconazole have the lowest MICs. Conclusion To date, 22 invasive infections involving H. aspergillata have been reported. On isolation of H. aspergillata, its pathogenic potential in clinical settings can be tricky. Molecular identification and antifungal susceptibility testing are essential considering high resistance against several antifungal therapies.

Hyicin 3682, a bioactive peptide produced by Staphylococcus hyicus 3682 with potential applications for food preservation

2011 ◽  
Vol 162 (10) ◽  
pp. 1052-1059 ◽  
Author(s):  
Patrícia Carlin Fagundes ◽  
Hilana Ceotto ◽  
Amina Potter ◽  
Maria Aparecida Vasconcelos de Paiva Brito ◽  
Dag Brede ◽  
...  
Keyword(s):  
Food Preservation ◽  
Bioactive Peptide ◽  
Potential Applications

Nanotechnology for Gene Delivery to the Eye

2009 ◽  
Vol 03 (01) ◽  
pp. 7 ◽  
Author(s):  
Swita R Singh ◽  
Uday B Kompella ◽  
◽  
Keyword(s):  
Gene Delivery ◽  
Enzymatic Degradation ◽  
Viral Vectors ◽  
Viral Vector ◽  
Target Cells ◽  
Loading Capacity ◽  
Adeno Associated Virus ◽  
Complementary Dna ◽  
Privileged Status ◽  
Potential Applications

The relatively immune-privileged status of the eye makes it an interesting target for gene delivery. Gene delivery to the eye using viral vectors via subretinal and intravitreal injections has been extensively investigated. Recently, the safety of recombinant adeno-associated virus vector expressing RPE65 complementary DNA (cDNA) in a limited clinical trial of three patients has also been reported. Nanotechnology-based non-viral vectors offer the advantages of safety and flexibility in terms of loading capacity and delivery system design compared with viral vectors. An ideal non-viral vector should be non-toxic, efficiently taken up into the target cells and conducive to gene expression, and should protect the gene against enzymatic degradation. Multiple kinds of nanotechnology-based non-viral vectors have been investigated for potential applications for gene delivery to the eye, namely nanoplexes, dendrimers, micelles, nanoparticles and liposomes. This article summarises and discusses key advances in the application of nanotechnology for gene delivery to the eye.

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