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Biomedical subjects

C A Bowles

Publications and source records attributed to C A Bowles.

At least 37 records · Page 2Linked to original sources
PubMed1981

A modification of the canine carotid-jugular shunt.

A shunt modification was used for implantation in the carotid-jugular vessels of the dog. The shunt was made of plastic tubing and was tied to each vessel with three silk ligatures. The tubing was exteriorized and anchored to the skin. The exposed tubing was cut and attached to the input and output lines of a tubing kit for leukapheresis with a continuous flow centrifuge. Surgical implantation of the shunt was accomplished with ease and minimum trauma to the animal. Useful life of the shunt extended over a 3-week period with minimal requirements for anticoagulants.

Animals↗
PubMed1979

Studies of the Pelger-Huët anomaly in foxhounds.

An inbred family of foxhounds with four members expressing the Pelger-Huët (P-H) anomaly is described. The disease-free status of all P-H affected dogs suggests a benign disorder, although review of breeding records indicated a lower percentage of pups weaned (63%) by P-H females compared with the percentage of pups weaned (81%) by outcrossed females throughout the foxhound colony. Light-microscopic examination of blood films from affected dogs revealed 50--67% neutrophils with round, oval, or bean-shaped nuclei and rarely (0.5%) segmented nuclei. Neutrophils examined by electron microscopy showed the nuclei to have a fine nuclear cleft and condensed chromatin and the cytoplasm to have mature heterochromatic granulation. Local P-H neutrophil mobilization through a standard skin abrasion into a chamber containing autologous serum was impaired at all time periods evaluated (1, 4, 8, and 24 hours) compared with the neutrophil mobilization by normal dogs. Antibody response to sheep erythrocyte immunization was also impaired. In vitro reactivity of normal and P-H lymphocytes stimulated by pokeweed mitogen was depressed when lymphocytes were cultured in plasma from a P-H dog but not when cultured in plasma from a normal dog. Vigorous blastogenic responses to phytohemagglutinin by normal and P-H lymphocytes cultured in P-H or normal plasma suggest the presence of a factor(s) in the P-H plasma which interferes with B-lymphocyte reactivity.

Animals↗
PubMed1977

Canine migration inhibitory factor: effect of Corynebacterium parvum administration.

Peripheral blood lymphocytes from dogs sensitized to streptolysin O (SLO) were assayed for migration inhibitory factor (MIF) production by the indirect MIF test, using guinea pig peritoneal exudate cells as the source of macrophages. A specific direct correlation was established between the degree of inhibition of migration and the concentration of SLO-stimulated supernatants from lymphocyte cultures (SLO-S) of untreated normal dogs. Undiluted SLO-S inhibited migration by 66.8%, whereas a dilution of 1:64 elicited a 3% inhibition. In parallel tests, purified protein derivative stimulation of lymphocytes from BCG-vaccinated dogs produced 92.6% inhibition. The effect of Corynebacterium parvum on SLO-specific MIF production was evaluated in three groups of dogs administered a single intramuscular injection of C. parvum at 5 or 50 mg/m(2) or 50 mg/m(2) in suspension with 10 mg of methylprednisolone. Inhibition of migration of macrophages exposed to a 1:4 dilution of SLO-S from dogs inoculated with C. parvum (5 mg/m(2)) was 33% greater (mean inhibition, 75%) than the same SLO-S dilution from uninoculated normal dogs (mean inhibition, 42%) (P < 0.0002). Similarly, lymphocytes from dogs administered 50 mg/m(2) caused an enhancement of migration inhibition, with a mean increase of 26% over controls (P < 0.002), whereas a dose of 50 mg/m(2) with methylprednisolone produced a 16% increase in migration inhibition (P < 0.05). The administration of C. parvum resulted in a three- to fourfold increase in the SLO-S dilution, which would reduce migration by 20% (MIF titer). This increase peaked between days 20 and 30 and lasted over 50 days post-C. parvum inoculation. These findings indicate that C. parvum specifically increases MIF production by canine lymphocytes in a linear correlation with SLO concentration and suggest its use as a stimulant of canine immunity.

Animals↗
PubMed1976

Canine allogeneic bone marrow transplantation. Technique and variables influencing engraftment.

We have studied the toxicity and immune suppression of supralethal total body irradiation (800-2000 rads, 60Co) at three dose intensities (10 rads/min, 49 rads/min, and 100 rads/min). In 79 intensively supported radiation control animals, the LD50(5) (tn 5 days) for these dose intensities is estimated to be 1556, 941, and 921 rads, respectively. A biomodal pattern of early (median 4 days) and late (median 9 days) deaths was observed corresponding to histopathological evidence of the intestinal and hematopoietic radiation syndromes. Random donor bone marrow transplants were performed in 83 animals to test immune suppression afforded by 800 rads and 1000 rads at dose intensities of either 10 rads/min or 49 rads/min. Bone marrow cell dose was varied to analyze its effect on engraftment. A greater degree of immunosuppression with less toxicity was achieved at the lower dose intensity. A minimum dose of 3-5 X 10(8) nucleated allogeneic bone marrow cells/kg (readily obtainable from living donors) resulted in a high percentage of engraftment with lethal graft-versus-host disease following conditioning with 1,000 rads midplane at 10 rads/min, the optimum regimen employed.

Animals↗
PubMed1975

Rosette formation by canine peripheral blood lymphocytes.

The surface membrane characteristics of canine peripheral blood lymphocytes were investigated using erythrocyte (E) and erythrocyte antibody complement (EAC) rosette assays and immunofluorescent staining techniques. Canine thymus-derived lymphocytes formed nonimmune E rosettes with human and guinea pig erythrocytes at approximately the same percentages (mean percentage 36.3 and 32.4, respectively). Rosettes did not form with erythrocytes from seven other animal species. Cell surface immunoglobulins were demonstrable in a small percentage (4%) of the E rosette-forming lymphocyte population. Fragments of human erythrocytes inhibited E rosette formation by intact human red cells, but did not result in a significant decrease in rosette formation by intact guinea pig erythrocytes; likewise, guinea pig fragments had no inhibitory effect on rosette formation by human erythrocytes, demonstrating that separate receptors were required for the two red cell types. EAC rosette formation was not affected by addition of intact or fragmented human and guinea pig erythrocytes. Canine bone marrow-derived lymphocytes were characterized by immunoglobulin on the cell surface and EAC rosette formation. Serial tests of lymphocytes from one dog revealed a wide variation in percentage of cells forming E and EAC rosettes. A close correlation was observed between the immunoglobulin-bearing cells (mean percentage 46.6) and those forming EAC rosettes (mean percentage 49.3).

Animals↗