SURGICAL TREATMENT OF DISEASES OF THE PLEURA, MEDIASTINUM AND THORACIC CAGE

The pleura, mediastinum and thoracic cage are rarely the center of attention for disease in the dog and the cat. Most often these structures are viewed as the wrappings for vital structures; their presence appears most often to interfere with visualization and palpation and impede surgical repair.     

Antisense RNA inactivation of myosin heavy chain gene expression in Dictyostelium discoideum

The role of myosin in the contraction of striated muscle cells is well known, but its importance in nonmuscle cells is not yet clear. The function of myosin in Dictyostelium discoideum has been investigated by isolating cells which specifically lack myosin heavy chain (MHC A) protein. Cells were transformed with a vector encoding RNA complementary to mhcA messenger RNA (antisense RNA). Stable transformants have a dramatic reduction in the amount of MHC A protein, grow slowly, and generate giant multinucleated progeny, indicating an impairment in cytokinesis. Surprisingly, the cells adhere to surfaces, extend pseudopods and are capable of ameboid locomotion. The developmental sequence that is initiated by starving cells is severely impaired by the lack of myosin. The cells are unable to form multicellular aggregates normally and do not undergo subsequent morphogenesis. By changing the food source from liquid medium to bacteria, expression of the endogenous mhcA messenger RNA can be increased relative to expression of antisense RNA. When grown in this way, the transformed cells accumulate MHC A protein, remain mononucleate, and proceed through development normally.     

CTLA-4 control over Foxp3+ regulatory T cell function

Naturally occurring Foxp3+CD4+ regulatory T cells (Tregs) are essential for maintaining immunological self-tolerance and immune homeostasis. Here, we show that a specific deficiency of cytotoxic T lymphocyte antigen 4 (CTLA-4) in Tregs results in spontaneous development of systemic lymphoproliferation, fatal T cell-mediated autoimmune disease, and hyperproduction of immunoglobulin E in mice, and it also produces potent tumor immunity. Treg-specific CTLA-4 deficiency impairs in vivo and in vitro suppressive function of Tregs-in particular, Treg-mediated down-regulation of CD80 and CD86 expression on dendritic cells. Thus, natural Tregs may critically require CTLA-4 to suppress immune responses by affecting the potency of antigen-presenting cells to activate other T cells.     

Results of surgical treatment for thoracolumbar disc protrusion

Ninety-nine dogs were treated by hemilaminectomy for thoracolumbar intervertebral disc protrusion. Most animals were 4–7 years old and chondrodystrophoid. The incidence of protrusion was higher at the thoracolumbar junction. Animals with paresis, pain, or pain and paresis had a greater recovery rate than dogs with paralysis. Résumé. La protrusion du disque intervertébral thoracolombaire a été traitée par hémi-laminectomie chez 99 chiens, la plupart âgés de 4 à 7 ans et atteints de chondrodystrophie. Les protrusions étaient plus fréquentes à la jonction thoraco-lombaire. Les animaux qui manifes-taient de la parésie ou de la douleur, ou de la parésie et de la douleur, se rétablissaient plus vite et mieux que les animaux paralysés. Zusammenfassung. Neunundneunzig Hunde wurden mit Hemilaminektomie bei thoraco-lumbaren Zwischenwirbelscheibenvorfall behandelt. Die meisten Tiere waren 4–7 Jahre alt und chondrodystrophoid. Die Häufigkeit von Diskushernien war höher am thoracolumbarem Über-gangsabschnitt. Tiere mit Parese, Schmerzen oder Schmerzen und Parese wurden häufiger wiederhergestellt als Hunde mit Paralyse.