The Canadian influenza decision, 1976

This paper explains the Canadian decision process following the isolation and identification of A/New Jersey/8/76 at Fort Dix, New Jersey in February 1976. The cause for concern was the emergence of a swine-like strain related to that which caused the 1918-19 pandemic, together with proved man-to-man transmission. This concern was reinforced since all new influenza A strains known to have infected the number of persons involved at Fort Dix have become strains of epidemic importance. The Fort Dix outbreak gave sufficient warning to allow implementation of a national vaccination program, to prevent and protect against influenza. In the past such an opportunity had not occurred, and vaccine use had, at best, constituted an intervention in the course of an outbreak. The National Advisory Committee on Immunizing Agents had all available information when it reached its decision to recommend vaccination with bivalent (A/Victoria and A/New Jersey) or with monovalent (A/New Jersey) vaccine for selective, high-risk groups. This was an independent, scientifically based decision.     

Pigmented lesions in newborn infants

1058 newborn infants were examined. Forty-one (3-9%) had clinically discernible pigmented lesions compatible with melanocytic naevi. Biopsy was performed on thirty-four of the forty-one and of these; eleven, representing 1-01% of the infants, proved to be melanocytic naevi. No giant (garment) naevi were seen in this series. Two of the eleven naevi pathologically examined showed histological changes similar to those that have been reported in some giant naevi, but the remaining nine were not only different from criteria usually assigned to giant naevi, but they also differed from the usual adult naevi, in that most were predominantly junctional. None of the melanocytic naevi in this series showed any suggestion of malignant change. In newborn infants it is often impossible clinically to distinguish naevi from other types of pigmented lesions, as only eleven out of the thirty-four pigmented lesions were melanocytic naevi. Seven of the eleven melanocytic naevi were under 1-5 cm in diameter. No pigmented lesions were found on the palms, soles or genitalia.     

Operative correction of pectus excavatum: an evolving perspective

Volatile free fatty acids (VFA) in blood increased approximately twofold in dogs subjected to total hepatectomy. The average total plasma VFA preoperatively was 1,585 mug percent and shortly before death, postoperatively, was 2,798 mug percent. The corresponding red cell concentrations were essentially the same. Acetic acid was 81 percent of the total VFA, propionic acid 7 percent, isobutyric acid 4 percent, butyric acid one percent, and isovaleric acid 5 percent. There was little or no isovalerate in red cells. The increments in the individual fatty acids after hepatectomy were highly variable, but the average increase with time was almost linear. The increase in VFA probably reflects an increased utilization of the branched-chain aminoacids by extrahepatic tissues.     

Relationship of senescence of corn (Zea mays L.) stalk pith, cob parenchyma and first developed leaf tissues to RNA content and synthesis

In stalk parenchyma tissue of WF9 X 38-11 single corn (Zea mays L.), there was a per cell increase in RNA synthesis and a slight increase in total RNA as cells became older. In cob parenchyma tissue of WF9 X 38-11 single cross corn, both total RNA content and RNA synthesis per cell decreased with the age of cells. In first developed leaf tissue of FR43 X FR14A single cross corn, RNA synthesis increased steadily but only slightly over its life span. The pattern of RNA synthesis and destruction in senescing leaf tissue of seedlings and two sources of parenchyma tissue of maturing plants appeared to differ.     

Purification and characterization of two forms of urokinase

Affinity chromatography on agmatine-Sepharose was used for the separation of two active forms of urokinase (EC 3.4.99.26) from partially purified human urinary urokinase. The approximate molecular weight of the heavier form was 47 000 and of the lighter 33 400. Both forms were homogeneous by sodium dodecyl sulfate gel electrophoresis and by 3H-labeled diisopropylphosphorofluoridate and 14C-labeled p-nitrophenyl-p'-guanidinobenzoate incorporation studies. The 33 400 mol. wt. form had a single chain, and the 47 000 mol. wt. form had two chains (33 100 and 18 600 mol. wt.) linked by disulfide bonds. The specific activity of the heavier form was 104 000 CTA units/mg protein, compared with 226 000 units/mg for the lighter form but the activities per mmol of active site (molar activities) of the two forms were almost identical (9.6-10(9) and 10.2-10(9) CTA units/mmol). Isoelectric focusing on gels showed that the 47 000 material contained one major subform with a pI of 8.60 and a minor subform with a pI of 8.90, while the 33 400 material had three major subforms with pI values of 8.35, 8.60 and 8.70, respectively, and a minor subform with a pI of 8.05. 3H-labeled diisopropylphosphorofluoridate incorporation studies revealed an active-site serine residue in the heavy chain.     

Incidence, technique of isolation, and treatment of group B streptococci in obstetric patients

A prospective study was performed to determine the incidence of group B streptococci cultured from the cervix in a series of obstetric clinic patients at St. Margaret's Hospital. Cultures were taken during each trimester and planted to both a blood agar plate and a selective broth medium. Of a total of 812 cultures, 18 were positive, an over-all incidence of 2.2 per cent. During the first, second, and third trimesters, 2.2 per cent, 2.5 per cent, and 1.9 per cent of cultures were positive, respectively. Women with positive cultures were treated with a 10 day course of oral penicillin or a suitable alternative; four of 16 had persistent positive cultures at the end of the first treatment period, three of these four responded to a second course of antibiotics, and the remaining patient responded after a third treatment course. The total number of positive cultures by selective broth was 24, compared to nine in blood agar, indicating a 2.7-fold increase in pickup by the selective broth.     

Interaction between radiation and drug damage in mammalian cells. II. The effect of actinomycin-D on the repair of the sublethal radiation damage in plateau phase cells

The effect of actinomycin-D (AMD) on radiation damage repair was studied in plateau phase V79 Chinese hamster cells. Sublethal radiation damage repair, as demonstrated by survival fluctuations following two x-ray exposures separted by time, was observed in our plateau phase cells. Plateau phase cells exposed to 0.01-0.04 mug/ml AMD (a nontoxic regimen to 8 hours) between x-ray exposures were less able to repair sublethal damage. If plateau phase cells were plated at low dilutions into fresh medium (conditions for resuming exponential growth) immediately after the first x-ray dose, and exposed to 0.01--0.04 mug/ml AMD until the second dose, inhibition of sublethal damage repair and additional cell killing were observed particularly at 0.04 mug/ml AMD. It is suggested that radiation-drug damage interactions should be studied in plateau phase cells and in cells resuming exponential growth after plateau phase (possibly analogous to "recruitment"), as well as in exponential phase cultures.     

Specific cytotoxicity in vitro of lymphocytes sensitized in culture against tumor cells

The production of tumor-specific cell-mediated cytotoxicity following in vitro sensitization of C57BL spleen cells against a syngeneic 3LL Lewis lung carcinoma was studied. Lymphocytes were sensitized on monolayers of the tumor cells for 4-5 days. The cytotoxicity was assayed by measuring the reduction in 3H-leucine and 3H-thymidine incorporation by target cells after interaction with the sensitized lymphocytes. Spleen lymphocytes sensitized on monolayers of 3LL tumor cells caused a high extent of lysis; such cells tested on C57BL or C3H fibroblast targets evoked only a low level of cytotoxicity. C57BL spleen cells sensitized on C57BL fibroblasts caused a low level of cytotoxicity when tested on a 3LL target. Thus cytotoxicity appeared to be tumor specific. The reduced incorporation into protein and DNA of target tumor cells caused by the sensitized lymphocytes was a measure of cell injury, which was more sensitive than direct cell count or uptake of 51CR. Lymphocytes from syngeneic tumor-bearing mice, tested 13-25 days after tumor inoculation, did not manifest in vitro cytotoxicity. On the contrary, such lymphocytes sometimes appeared to have a promoting effect on the tumor cells.     

Bird breeder's hypersensitivity pneumonitis: progress studies of lung function after cessation of exposure to the provoking antigen

Lung function and immunologic studies have been performed in 9 patients with bird breeder's hypersensitivity pneumonitis at the time of diagnosis and at intervals from 8 to 30 months after they ceased exposure to the provoking antigen. All 9 patients had evidence of small airway obstruction at the time of diagnosis. Complete recovery of lung function occurred in 4 patients. The other 5 all had evidence of interstitial damage; 3 of them had progressive increase in the degree of airway obstruction, and one had progressive loss of elastic recoil. The patients were nonsmokers, and these progressive changes could not be explained by occult exposure to antigen because the tests of immunologic sensitivity to relevant avian antigens became negative. Neither the nature or degree of lung function abnormality nor the form of clinical presentation was related to the development of residual damage. The period of exposure to antigen after symptoms developed and the age of the patient appeared to be the most important factors determining recovery of lung function.     

Healing of deep venous thrombosis: venographic findings in a randomized study comparing streptokinase and heparin

Sequential ascending venographic studies were used to assess the healing of deep venous thrombosis in 50 patients randomly assigned to streptokinase or heparin therapy. Various degrees of thrombolysis and/or recanalization were demonstrated by venograms performed on the fourth and tenth days of treatment. Late follow-up studies (mean, 7 months after treatment) showed three basic patterns of resolution: (1) return to normal, (2) complete recanalization, and (3) incomplete recanalization and/or collateralization. Loss of valves or their function was associated with recanalization. The character, speed, and outcome of healing reflected the nature and extent of thrombosis, prior thrombotic disease in the extremity, and the type and timing of treatment. Streptokinase was highly effective and preferable to heparin in patients with deep vein thrombosis when therapy was begun within 4 days of onset of symptoms. In later stages of acute or recurrent deep vein thrombosis, the effectiveness of both drugs was significantly reduced.