Comp Med No. 5 2011 Flashcards
True/False: Lactate dehydrogenase-elevating virus is an enveloped RNA virus belonging to the family Arteriviridae?
True
What is the most common source of LDV infection of mice?
Contaminated transplantable tumors and experimental biological material
What is the classical method of detecting LDV contamination in biological materials?
Measuring serum LDH levels of mice inoculated with test biological materials.
LDV has a tropism for what type of cells?
mouse macrophages that express F4/80 cell surface antigen
True/False: LDV infection of mice results in transient viremia and clearance of the infection.
False: LDV results in lifelong viremia
What are some of the observed immune system effects of LDV infection of mice?
Elevation of plasma IgG, autoantibody production, immune complex formation, enhanced or suppressed tumor development.
What strains of mice, when immunocompromised, are prone to developing poliomyelitis when infected with LDV?
AKR & C58 - strains that are homozygous for the Fv1n allele (also C3H/Fg and PL/J mice)
What components are necessary for the development of LDV-induced poliomyelitis?
1) The presence of multiple proviral copies of the N-tropic endogenous murine leukemia viruses (MuLV) 2) homozygosity of the permissive allele for MuLV replication (Fv1n/n)
What molecules are detected in Northern Blot, Southern Blot, and Western Blot?
Northern = RNA detection Southern = DNA detection Western (& Eastern) = protein detection
N-methyl-N’-nitro-N-nitrosoguanidine (MNNG) in drinking water induces what in rats, hamsters & dogs?
Gastric cancer
Proliferating cell nuclear antigen is known as a marker for what?
Marker of cellular proliferation and serves as a prognostic marker for gastric carcinoma malignancy
MNNG induced gastric carcinoma occurs more frequently in male or female Wistar rats?
Male
With regard to animal models of hemorrhagic shock, what is the difference between fixed-pressure and fixed-volume models?
In fixed-pressure models, hemorrhagic shock is achieved by withdrawing blood until the desired MAP is reached and during the shock period, the blood pressure is held at this value by further blood withdrawal or reinfusion of collected blood or other fluids. In fixed-volume models, a fixed blood volume is removed which is calculated based on the animal body weight.
What factors may affect the accuracy of calculating blood volume based on body weight?
The circulating blood volume of mammals does not strictly correlate with body weight due to individual differences in the relation of blood volume to mass of fat and muscle tissue and does not linearly increase with body weight gain….heavier animals usually have more fat and therefore comparatively less blood.
Which of the following are limitations of current models of osteochondral allograft transplantation: a. Large surface area b. Thick articular cartilage layer c. Cost associated with use of large animal models. d. The use of suture for graft fixation
c. Cost associated with use of large animal models.
T/F: Superficial zone protein (SZP) up-regulation is associated with increased incidence of osteoarthritis.
False: OA is associated with a down regulation of SZP; SZP is also known as lubricin, MSF precursor, proteoglycan 4 (PRG4)