Ultrastructural pathology and interorganelle cross talk in hepatotoxicity.

Mitochondria, endoplasmic reticulum (ER), cytoplasmic lipid droplets (CLD), and Golgi vesicles use cross talk to control hepatocyte metabolism, growth, and stress. Interpretation of ultrastructural change requires knowledge of how cross talk pathways function, how differential activation of hepatocellular signals influences organelle structure, and how organelles position themselves to become central hubs for stress responses. Mitochondria, by coupling energy production to pathways for protection, form critical platforms for innate signaling.

Gliomatosis cerebri in two dogs.

A 3.5 yr old Saint Bernard was evaluated for nonambulatory tetraparesis and cranial nerve dysfunction, and a 7 yr old rottweiler was evaluated for progressive paraparesis. Clinical signs of left-sided vestibular and general proprioceptive ataxia and cranial nerve VII dysfunction in the Saint Bernard suggested a lesion affecting the brain stem.

Absence of Mycobacterium avium subspecies paratuberculosis components from Crohn's disease intestinal biopsy tissues.

Background: Crohn's disease is a chronic human intestinal inflammatory disorder for which an etiologic agent has not been identified. Johne's disease is a similar chronic enteric granulomatous disease of ruminant species and has been used as a model of Crohn's disease. Johne's disease has been proven to be caused by Mycobacterium avium subspecies paratuberculosis (M.

Investigation of antigen-specific T-cell responses and subcutaneous granuloma development during experimental sensitization of calves with Mycobacterium avium subsp paratuberculosis.

Objective: To characterize the early cellular immune response to Mycobacterium avium subsp paratuberculosis (MAP) infection and evaluate the development of granulomatous inflammation at the SC injection site in experimentally inoculated calves.

Animals: Forty-eight 4-week-old calves.

Procedure: Calves received an SC injection of MAP strain 19698 (n = 25), sterile saline (0.

Clinical and pathologic comparison of acute leptospirosis in dogs caused by two strains of Leptospira kirschneri serovar grippotyphosa.

Objective: To develop a method for inducing acute leptospirosis in dogs.

Animals: 31 nine-week-old female Beagles.

Procedure: Beagles were randomly assigned to 2 inoculation groups or a control group.

Cytokine effects on maturation of the phagosomes containing Mycobacteria avium subspecies paratuberculosis in J774 cells.

Mycobacterium avium subspecies paratuberculosis (M. a. ptb) is an intracellular pathogen of macrophages.

Segmented filamentous bacteria interact with intraepithelial mononuclear cells.

Segmented filamentous bacteria (SFB) are found in multiple species and play an important role in the development of mucosal immunity. The mechanism by which the bacteria interact with the immune system has not been well defined. We provide morphologic evidence of direct interaction between SFB and intraepithelial mononuclear cells.