Show Advanced Search

REFINE YOUR SEARCH:

Containing Text
- - -
+
Filter by author or institution
GO
Filter by publication date
From:
October, 2006
Until:
Today
Filter by journal section

Filter by science education

 
 
Botulinum Toxins: Toxic proteins produced from the species Clostridium botulinum. The toxins are synthesized as a single peptide chain which is processed into a mature protein consisting of a heavy chain and light chain joined via a disulfide bond. The botulinum toxin light chain is a zinc-dependent protease which is released from the heavy chain upon Endocytosis into Presynaptic nerve endings. Once inside the cell the botulinum toxin light chain cleaves specific Snare proteins which are essential for secretion of Acetylcholine by Synaptic vesicles. This inhibition of acetylcholine release results in muscular Paralysis.

Lysogenic Cycle of Bacteriophages

JoVE 10824

In contrast to the lytic cycle, phages infecting bacteria via the lysogenic cycle do not immediately kill their host cell. Instead, they combine their genome with the host genome, allowing the bacteria to replicate the phage DNA along with the bacterial genome. The incorporated copy of the phage genome is called the prophage. Some prophages can re-activate and enter the lytic cycle. This often occurs in response to a perturbation, such as DNA damage, but can also transpire in the absence of external cues. In some cases, the genes encoded by prophages can alter the phenotype of the infected bacterium, a process known as lysogenic conversion. Some phages encode proteins or toxins called virulence factors that can facilitate bacterial infections. Through lysogenic conversion, normally non-pathogenic bacteria can become highly virulent via infection by a phage carrying virulence factors. For example, such phages are largely responsible for the pathogenicity of the bacterial species that cause botulism (Clostridium botulinum), diphtheria (Corynebacterium diphtheriae), and cholera (Vibrio cholerae). Without lysogenic conversion, these bacteria do not usually cause disease. A particularly well-studied example of lysogenic conversion is that of the Escherichia coli strain O157:H7. Several massive food recalls have stemmed

 Core: Biology

Solutions and Concentrations

JoVE 10078

Source: Laboratory of Dr. Michael Evans — Georgia Institute of Technology


A solution is a homogeneous mixture containing some components in small amounts, called solutes, and one component in a large amount, called the solvent. Solid-liquid solutions contain one or more solid solutes dissolved in a liquid solvent. Solutions are…

 General Chemistry

Isokinetic Robotic Device to Improve Test-Retest and Inter-Rater Reliability for Stretch Reflex Measurements in Stroke Patients with Spasticity

1Department of Medical Assistant Robot, Daegu Research Center, Korea Institute of Machinery & Materials, 2Department of Rehabilitation Medicine, Seoul National University College of Medicine, Seoul National University Bundang Hospital, 3School of Mechanical and Aerospace Engineering, Seoul National University/IAMD

JoVE 59814

 Bioengineering

Surface Electromyographic Biofeedback as a Rehabilitation Tool for Patients with Global Brachial Plexus Injury Receiving Bionic Reconstruction

1Clinical Laboratory for Bionic Extremity Reconstruction, Medical University of Vienna, 2Department of Orthopaedics and Trauma Surgery, Medical University of Vienna, 3Department of Bioengineering, Imperial College London, 4Division of Plastic and Reconstructive Surgery, Department of Surgery, Medical University of Vienna

JoVE 59839

 Neuroscience
123
More Results...