Lymphomas associated with a tolerant lymphocytic choriomeningitis virus infection in mice.

On each of 2 occasions when a tolerant lymphocytic choriomeningitis (LCM) virus infection was introduced experimentally by a natural route into breeding stock of the Pirbright P(SD) mouse strain, and a comparison made with genetically identical controls, where was in successive generations an overall 15-fold increase in the incidence of lymphomas. Most of these were recognized clinically after the age of 16 months. The same observation was made in mice of the P(H) strain from which the P(SD) strain had been surgically derived.

Human fibroblast interferon: amino acid analysis and amino terminal amino acid sequence.

The purification of human fibroblast interferon has been simplified to a two-step procedure consisting of affinity chromatography on Blue Sepharose and sodium dodecyl sulfate polyacrlamide gel electrophoresis. A preliminary amino acid composition and the sequence of the 13 amino-terminal residues of homogeneous interferon prepared by this method is reported.

A barrier cabinet for mice based on the Houghton chicken isolator.

Nuclei of a disease-free foundation stock of mice housed in a barrier unit and a barrier cabinet constructed from resin-bonded glass-fibre were compared over a period of 7 years. The cabinet was found to be a satisfactory alternative to a flexible-film isolator and was thought to be preferable. A description is given of the cabinet, the method of sterilization and the breeding schedules for 2 generations adopted to make the maximum use of the 10-month life of the high-efficiency filter employed.

Leukemic infiltration of penis.

Leukemic infiltration of the urinary tract is most common in the kidneys. Other areas are involved much less frequently. We report a case of leukemic infiltration of the penis.

Vascular access for cancer chemotherapy.

Eleven bovine heterografts were utilized in the repetitive administration of chemotherapy in 10 patients with insufficient vascular access. Six grafts remained patent until the time of death and five grafts clotted from 71 to 1110 days postoperatively. Three patients are alive and well.

Fibroblast interferon induces synthesis of four proteins in human fibroblast cells.

Treatment of human diploid fibroblasts with fibroblast interferon for 8 hr inhibited replication of vesicular stomatitis virus. When the total cell protein of cells treated with interferon for 8 hr was compared to the total cell protein of untreated cells by two-dimensional gel electrophoresis, the interferon-treated cells were found to contain four proteins not found in untreated cells. Addition of actinomycin D to the cells concurrently with interferon inhibited the synthesis of the four proteins.

Epidermal tissue as a primary site of replication of lymphocytic choriomeningitis virus in small experimental hosts.

When fresh urine from LCM tolerantly infected mice was applied to small areas of excoriated skin of guinea-pigs undiluted or diluted 10(-1), a high LCM infectivity developed in the local dermal tissue within 3 days and quickly spread to the lymphatic system. The skin at this site of infection became erythematous 10--12 days after infection and a few days later a rash was often seen in the hairless skin around the mammary teats. A viraemia was first detected at about 8 days after infection and persisted for at least 8 days, during which time a high infectivity titre in skin not only at the infection site but also distal to it suggested that there was a generalized active infection of the dermis.

Preparation of 125iodine-labelled human fibroblast interferon.

Human fibroblast interferon has been labelled with 125iodine using the Bolton-Hunter reagent. Purification of the interferon after iodination gave a product which had stable biological activity for 1 month and had a specific radioactivity of 2 to 4 micronCi/microgram.

Effects of salicylamide and protein restriction on the skeletal development of the rat fetus.

Salicylamide has previously been shown to be teratogenic to the rat. Aims of the present study were to examine separate effects and interactions of salicylamide administration and protein restriction on development of the rat fetus. In experiments using Holtzman rats,the percentage of fetal resorptions was significantly increased by drug treatment and by protein restriction.

Effect of salicylamide on the placental transfer and fetal tissue distribution of sodium-35S-sulfate in the rat.

Pregnant rats were used to determine effects of salicylamide on the sequential uptake and loss of radiosulfate by maternal and fetal tissues. Separate and combined effects of salicylamide and protein restrictions on radiosulfate retention by fetal rat tissues were determined. Rats were fed salicylamide-containing or control diets from the 4th or 6th day of gestation.

Considerations in our search for interferons for clinical use.

Interferon has yet to become the drug of choice for any clinical disease entity, but several promising uses are being pursued. Clinical trials are limited probably because interferon is so expensive. Cheaper interferon would probably stimulate more clinical trials.

The use of "fresh" unstented homograft valves for replacement of the aortic valve: analysis of 6 1/2 years experience.

Between August 1969 and January 1976, 561 patients underwent homograft replacement of the aortic valve (AVR). Isolated AVR was performed in 339 patients, ranging in age between 18 months and 74 years. The valves were sterilized in antibiotic solution and preserved at 4 degrees C in tissue culture medium.

Murine lymphocytic choriomeningitis: the history of a natural cross-infection from wild to laboratory mice.

A new locus of wild house mice tolerantly infected with the virus of lymphocytic choriomeningitis (LCM) has been identified in the United Kingdom. Evidence is presented which indicates that these mice were the source of infection in a laboratory mouse breeding colony, the mode of transmission probably being bites on tails and limbs exposed through wire-grid flooring. The results of an experiment which simulated indirect exposure of SPF mice to tolerantly infected wild mice supported earlier observations that without injury to the epidermis the risk of spread of infection from the infective urine, saliva or faeces is low.

Multisurface glass roller bottle for growth of animal cells in culture.

A multisurface glass roller bottle has been constructed for the growth of animal cells in culture. This bottle contains five concentrically placed glass cylinders that provide additional surfaces for the growth of animal cells. The bottle occupies the same space as a standard roller bottle, but it contains nine times the surface area of a standard bottle.

Pharmacological basis for antihypertensive effects of intravenous labetalol.

Labetalol 1-5 mg/kg administered intravenously to normal subjects in the supine position produced an immediate mean fall in systolic (16%) and diastolic (25%) blood pressure with a concomitant increase in heart rate (12%). After graded exercise, intravenous labetalol inhibited increases in heart rate and blood pressure. Isoprenaline log dose response curves of increase in heart rate and reduction in diastolic pressure after intravenous labetalol shifted to the right in a parallel manner compared with pre-labetalol response curves suggestive of competitive antagonism at beta-adrenoceptor sites.

Coronary angiography Review of 1500 consecutive cases.

Fifteen hundred coronary angiograms have been performed by the staff of Harefield Hospital since 1970. Only 2 deaths have occurred in the last 1000 consecutive cases though there were 5 in the first 500 cases. This drop in the mortality is ascribed to careful attention to detail and better training of the operators.