Normal human neutrophils are a source of a specific interleukin 1 inhibitor

In the course of our study on neutrophil production of an interleukin 1 (IL-1)-like factor, we found that the addition of polymorphonuclear neutrophils (PMN) to monocytes cultured in the presence of zymosan resulted in decreased IL 1 activity of the resultant supernatant, suggesting that PMN may contain an inhibitor of IL 1. The objective of this investigation was to study this IL 1 inhibitor which normal human PMN contain. The inhibitor is constitutively present in the PMN because 0 hr PMN lysates and unstimulated PMN supernatants also show inhibitory activity. The PMN inhibitor inhibits IL 1 (crude and partially purified) in a dose-response manner and does not affect basal [3H]thymidine incorporation in the presence or absence of PHA-P. The PMN inhibitor does not have any effect on interleukin 2 (IL 2)-induced proliferation of the IL 2-dependent CTLL cells. The inhibitor can be generated in the absence of serum and is not produced as a result of proteolytic activity from PMN enzymes. The inhibitor is heat-labile and is most stable at neutral pH. Gel filtration studies on Sephadex G-200 indicate that the inhibitor is heterogeneous in size. Two inhibitory peaks, at 45,000 to 70,000 m.w. and at greater than 160,000 m.w., were observed. When zymosan-stimulated PMN supernatant was chromatographed, there was separation of inhibitory factor from a 17,000 m.w. proliferating factor. Presence of this PMN inhibitor may be important in negative regulation of IL 1.

In vitro activity of aryl fluoroquinolones, Abbott 56619 and Abbott 56620, compared to ciprofloxacin, norfloxacin and beta-lactams versus multidrug-resistant Enterobacteriaceae and Pseudomonas aeruginosa

The new aryl fluoroquinolones, Abbott 56619 and Abbott 56620, were compared to ciprofloxacin, norfloxacin and newer beta-lactam agents in standardized microtiter testing versus multidrug-resistant gram-negative bacilli. Ciprofloxacin, followed by Abbott 56620, was generally the most active quinolone and imipenem the most active beta-lactam agent.

Isolation of feline rotaviruses and their relationship to human and simian isolates by electropherotype and serotype

Rotaviruses were detected by electron microscopy in the faecal specimens of six clinically well cats and virus was subsequently isolated from four of them. Analysis of the RNA of the isolates showed the existence of three electrophoretic types characteristic of the 'long' RNA electrophoretic pattern exhibited by rotaviruses. All feline isolates were neutralized only by antiserum to SA11 rotavirus, indicating that these isolates were serotype 3 rotaviruses. Antiserum prepared against a feline strain neutralized all the feline isolates as well as SA11 but showed no neutralizing activity against human isolates of serotype 1, 2 or 4.

Class II histocompatibility antigen-mediated immunologic function of normal articular chondrocytes

Using monoclonal antibodies, we examined the display of rabbit Ia by articular chondrocytes. We found that 29 to 46% of chondrocytes displayed Ia antigen compared with 46 to 60% of spleen cells. Ia antigen expression was not likely to be the result of enzyme treatment. To investigate antigen presenting activity of enzyme dissociated normal articular chondrocytes, adult rabbits were immunized in the front foot pads with ovalbumin (OVA) in complete Freund's adjuvant. Four to six weeks later, draining popliteal lymph node cells (LNC) were obtained. Articular chondrocytes were obtained by overnight collagenase, DNase, and hyaluronidase digestion of cartilage from both ends of femurs and proximal end of tibias. Antigen-presenting cells from spleen were used as positive controls. LNC and nylon wool-purified T cells were cultured with OVA pulsed and mitomycin C-treated chondrocytes or spleen cells, and lymphocyte proliferation was measured by 3H-TdR uptake. Both chondrocytes and spleen cells showed antigen presenting activity, and stimulation of lymphocyte proliferation was inhibited by murine monoclonal anti-rabbit Ia antibody (2C4), whereas control plasmacytoma cell supernatants had no effect. When T cells were purified first by Sephadex G-10 and later by nylon wool columns, these cells were dependent on antigen-presenting cells for immunogen (OVA)-induced lymphocyte proliferation. Again, chondrocytes under these strict experimental conditions presented antigen to T cells. Chondrocytes also stimulated autologous and allogeneic normal lymphocytes. Thus, normal chondrocytes have Ia antigens on their surface and can function as antigen-presenting cells. These results are significant for the understanding of local cellular interaction in the pathogenesis of rheumatoid arthritis.

Class II histocompatibility antigen-mediated immunologic function of normal articular chondrocytes

Using monoclonal antibodies, we examined the display of rabbit Ia by articular chondrocytes. We found that 29 to 46% of chondrocytes displayed Ia antigen compared with 46 to 60% of spleen cells. Ia antigen expression was not likely to be the result of enzyme treatment. To investigate antigen presenting activity of enzyme dissociated normal articular chondrocytes, adult rabbits were immunized in the front foot pads with ovalbumin (OVA) in complete Freund's adjuvant. Four to six weeks later, draining popliteal lymph node cells (LNC) were obtained. Articular chondrocytes were obtained by overnight collagenase, DNase, and hyaluronidase digestion of cartilage from both ends of femurs and proximal end of tibias. Antigen-presenting cells from spleen were used as positive controls. LNC and nylon wool-purified T cells were cultured with OVA pulsed and mitomycin C-treated chondrocytes or spleen cells, and lymphocyte proliferation was measured by 3H-TdR uptake. Both chondrocytes and spleen cells showed antigen presenting activity, and stimulation of lymphocyte proliferation was inhibited by murine monoclonal anti-rabbit Ia antibody (2C4), whereas control plasmacytoma cell supernatants had no effect. When T cells were purified first by Sephadex G-10 and later by nylon wool columns, these cells were dependent on antigen-presenting cells for immunogen (OVA)-induced lymphocyte proliferation. Again, chondrocytes under these strict experimental conditions presented antigen to T cells. Chondrocytes also stimulated autologous and allogeneic normal lymphocytes. Thus, normal chondrocytes have Ia antigens on their surface and can function as antigen-presenting cells. These results are significant for the understanding of local cellular interaction in the pathogenesis of rheumatoid arthritis.

Retrograde amnesia effects of intravenous diazepam in endoscopy patients

The presence of a retrograde amnesia, when caused by medications given prior to a medical procedure, can pose the medicolegal question of informed consent. This study investigated the retrograde amnesic effects of intravenous diazepam administered prior to gastrointestinal endoscopy. No significant retrograde amnesia was found in case subjects when compared with controls.

Radioimmunofocus assay for detection and quantitation of human rotavirus

A radioimmunofocus assay suitable for quantitation of cell culture-adapted human rotavirus was developed. The method was reproducible, more sensitive than plaque assay, and useful to detect and quantify strains of rotavirus which do not produce plaques. Preliminary results also suggested that the technique will be a useful means of serotyping cell culture-adapted strains of the virus.

Thymic branchial cysts in the dog and cat

Branchial cysts of the thymus were diagnosed in 15 dogs and 2 cats. The main clinical sign was dyspnea. Pleural effusion varied in degree from minimal to severe. In all animals, an encapsulated mass in the cranial mediastinal region was found to consist of multiple epithelial cysts embedded in a stroma of fibrous connective tissue, adipose tissue, and vessels. Surgical resection of the cysts was performed in 7 dogs; 3 dogs survived and were clinically normal for 18 to 36 months.

Myopathy in the nyala

Between January 1973 and June 1981, a total of 21 nyalas (Tragelaphus angasi) died with clinical and/or pathologic evidence of myopathy. The main clinical signs were stiffness, inability to rise, and failure to suckle in newborn fawns. Death usually occurred without premonitory signs of disease. Gross lesions were characterized by white or pale patches of skeletal or cardiac muscle. Histologically, acute degeneration or necrosis and mineralization were commonly observed in skeletal muscle. Acute necrosis of the myocardium with or without arteriolar fibrinoid necrosis was usually found in juvenile animals. Interstitial fibrosis of the myocardium with arteriosclerosis was commonly observed in adults. The plasma alpha tocopherol values of 3 affected nyalas ranged from 0.03 to 0.08 mg/dl (mean, 0.05 mg/dl). Unaffected nyalas from the same herd had a range of 0.09 to 0.24 mg/dl (mean, 0.13 mg/dl), which is low enough to be considered clinically deficient. The blood selenium values of the affected nyalas and other nyalas from the same herd ranged from 0.30 to 0.33 ppm (mean, 0.32 ppm), and were considered normal.

Excessive moderator bands in the left ventricle of 21 cats

Excessive numbers of moderator bands bridging the left ventricular septum and free wall and entangling papillary muscles were associated with heart failure and death in 21 cats. Clinical findings included dyspnea, anorexia, hypothermia, cardiomegaly, pleural effusion, plumonary edema, heart murmurs, gallop rhythm, electrocardiographic abnormalities (especially conduction disturbances), increased left ventricular end-diastolic pressure, angiocardiographic evidence of left ventricular restriction, and aortic thromboembolism. Pathologic changes included a morphologically distinct network of abnormal numbers of moderator bands in the left ventricle, left ventricular hypertrophy (younger cats--mean age, 4 years) or dilatation (older cats--mean age, 8.7 years), left atrial enlargement and hypertrophy, and pulmonary edema with heart failure cells in the alveoli. Heart weights of affected cats were significantly less than those of cats with congestive, hypertrophic, and restrictive cardiomyopathy (endocardial fibrosis), but were not significantly less than heart weights of clinically normal cats. Pathologic changes were characteristic of the syndrome grossly and histologically, but clinical findings were not clearly definable.

Dietary lipids and serum cholesterol level: change in diet confounds the cross-sectional association

In the Chicago Western Electric Company study, diet was assessed at the initial examination, in 1957-1958, of 1900 middle-aged men and again at their second examination about one year later. At the first examination, lipid composition of the diet, as summarized by a score based on the formula of Keys, Anderson and Grande (Grande, F. Predicting change in serum cholesterol from change in lipid composition of the diet. In: Lauer RM, Shekelle RB, eds. Childhood Prevention of Atherosclerosis and Hypertension. New York: Raven Press, 1980:145-53), was positively associated with level of serum cholesterol. Between the first and second examinations, however, hypercholesterolemic men were more likely than others to have reduced intake of dietary saturated fatty acids and cholesterol. As a result, at the second examination the cross-sectional linear association between the diet score and serum cholesterol concentration was significantly positive for men with initial levels of serum cholesterol less than 250 mg/dl, significantly negative for men with initial levels of 250 mg/dl or higher and not significantly different from zero for all men together. The bias introduced by change in diet among hypercholesterolemic men differs importantly from bias due to unreliability of measurement and to interindividual differences in intrinsic level of serum cholesterol, because it can produce statistically significant but spurious correlations.

Dietary vitamin A and risk of cancer in the Western Electric study

Intake of dietary provitamin A (carotene) was inversely related to the 19-year incidence of lung cancer in a prospective epidemiological study of 1954 middle-aged men. The relative risks of lung cancer in the first (lowest) to fourth quartiles of the distribution of carotene intake were respectively, 7.0, 5.5, 3.0, and 1.0 for all men in the study, and 8.1, 5.6, 3.9, and 1.0 for men who had smoked cigarettes for 30 or more years. Intake of preformed vitamin A (retinol) and intake of other nutrients were not significantly related to the risk of lung cancer. Neither carotene nor retinol intake was significantly related to the risk of other carcinomas grouped together, although for men in whom epidermoid carcinomas of the head and neck subsequently developed, carotene intake tended to be below average. These results support the hypothesis that dietary beta-carotene decreased the risk of lung cancer. However, cigarette smoking also increases the risk of serious diseases other than lung cancer, and there is no evidence that dietary carotenoids affect these other risks in any way.

Urinary calculi associated with portosystemic shunts in six dogs

Portosystemic shunts were diagnosed in 6 dogs with urinary calculi and signs of neurologic disease. Five of the dogs were initially examined because of neurologic signs, and 1 was seen because of urinary tract problems. The composition of the calculi was variable, but in all 13 episodes of calculi formation, the calculi contained an ammonium or uric acid component. One dog is being controlled under medical management; 4 of the dogs died, and 1 was euthanatized. The interpretation of pathogenesis was that decreased delivery of blood to the liver due to shunting or decreased liver function can potentially result in high blood concentrations of ammonia and uric acid, both of which are metabolic end products cleared by the kidneys; thus, the urinary tract would be an excellent environment for the precipitation of their salts.

Diet, serum cholesterol, and death from coronary heart disease. The Western Electric study

Over twenty years ago, we evaluated diet, serum cholesterol, and other variables in 1900 middle-aged men and repeated the evaluation one year later. No therapeutic suggestions were made. Vital status was determined at the 20th anniversary of the initial examination. Scores summarizing each participant's dietary intake of cholesterol, saturated fatty acids, and polyunsaturated fatty acids were calculated according to the formulas of Keys and Hegsted and their co-workers. The two scores were highly correlated, and results were similar for both: there was a positive association between diet score and serum cholesterol concentration at the initial examination, a positive association between change in diet score and change in serum cholesterol concentration from the initial to the second examination, and a positive association prospectively between mean base-line diet score and the 19-year risk of death from coronary heart disease. These associations persisted after adjustment for potentially confounding factors. The results support the conclusion that lipid composition of the diet affects serum cholesterol concentration and risk of coronary death in middle-aged American men.

Canine tuberculosis

In a survey of 15,272 canine necropsies, natural infection with Mycobacterium tuberculosis was found to have been diagnosed in eight dogs (0.05%). Clinical findings were anorexia, loss of body weight, lethargy, vomiting, and leukocytosis; radiography revealed pleural and pericardial effusion, ascites, and hepatomegaly. Granulomatous lesions with acid-fast bacilli were consistently found. Mycobacterium tuberculosis was isolated from lesions in the lungs, liver, or lymph nodes of five dogs. All eight dogs had a history of contact with human patients with tuberculosis.