Results of a repeat television-advertised mass screening program for colorectal cancer using fecal occult blood tests.

The results of a 1987 television-advertised colorectal screening program using fecal occult blood tests (FOBT) are compared with the initial 1986 program (results in parentheses). In the 1987 program, 73,508 fecal occult blood test (FOBT) kits were distributed free of charge, of which 63% were returned for analysis (57,000, 53%). Twenty-five percent of persons from the initial screening participated again in the 1987 program: 1,303 or 2.8% of persons had a positive screen (1,165, 3.9%). The predictive value of a positive screen was 23% for an adenomatous polyp and 8% for colorectal cancer (22%, 8%). Seventy-nine percent of the cancers detected were Dukes A or B or carcinoma in situ (78%). In order to promote a more thorough diagnostic work-up in positive screenes, a suggested diagnostic algorithm for the work-up of a positive FOBT was sent to participating physicians. Despite this, 35% of positive screenees had a diagnostic work-up limited to a repeat FOBT, and/or sigmoidoscopy only (32%). In conclusion, television-advertised mass screening programs consistently enroll large numbers of participants. The rate of compliance (percent of kits returned) and the limited diagnostic evaluation of persons with a positive screen appear to be the major factors limiting the success of our screening program.

Results of a television-advertised public screening program for colorectal cancer.

We report the results of a free, television-advertised mass screening program for colorectal cancer using stool guaiac kits. A total of 57,000 test kits were picked up and 29,619 (53%) were returned; 3.9% (1165) of the tests were positive. Ninety-three percent of persons with a positive screen sought medical evaluation after screening. Detailed follow-up was available on 744 persons. Fifty-eight persons had large-bowel carcinomas diagnosed, 80% of which were localized. One hundred sixty persons had adenomatous polyps removed. Forty percent of cancers and 58% of polyps were detected in persons with only one or two positive test slides out of a total of six. In 33% of persons with a positive screen, the diagnostic workup consisted of a repeated stool guaiac test and/or sigmoidoscopy only. A major drawback to improving the results of mass screening programs for colorectal cancer is the limited gastrointestinal workup conducted by physicians in many persons with a positive fecal occult blood test.

Preeclampsia in twin pregnancy--severity and pathogenesis.

The incidence of preeclampsia in a consecutive series of 642 twin pregnancies was 25.9% compared with 9.7% in singleton pregnancies (p less than 0.001); in primiparas it was 35.2% and in multiparas 20.4% (p less than 0.001). Preeclampsia in twin pregnancies was more commonly of early onset (p less than 0.001) and the maternal disease more severe as assessed by the incidences of severe hypertension (p less than 0.001), proteinuria (p less than 0.004), and eclampsia (p less than 0.01). There were 1 maternal and 12 perinatal deaths. Oestriol excretion before the emergence of preeclampsia was lower in patients with severe compared with milder preeclampsia (p less than 0.05) as was plasma glucose concentration (p less than 0.05). Mean birth and placental weights according to gestation, tended to be lower in the severe group compared with uncomplicated cases and those with milder preeclampsia, as were also the placental-fetal weight ratios. The similarity of results with those already reported for singleton pregnancy suggested a similar pathogenesis for preeclampsia in twin and singleton pregnancies.

A novel technique for efficient multiple sample dialysis.

Conventional methods for dialyzing numerous samples are either expensive or tedious and inefficient. These disadvantages were overcome through the construction and use of a Plexiglas dialysis sample holder (DSH). Large numbers of dialysis samples having 0.5 to 2.0-ml volumes may be attached to numbered positions on the DSH. Sample identification is greatly simplified and considerable savings in time and material are achieved. Furthermore, the risk of sample spill or mixing during filling or emptying of dialysis sacks, and the risk of leaks in dialysis tubing, are minimized.

Whole blood viscosity in preeclampsia.

Whole blood viscosity was measured in 41 patients with preeclampsia and in 51 normotensive control subjects. The mean viscosity in the preeclamptic group had a highly significant elevation (t = 9.752, p less than 0.001, at a shear rate of 0.1 sec-1 and t = 4.223, p less than 0.001, at a shear rate of 100 sec-1). The slower shear rate gave the better discrimination between the two groups as only four patients with preeclampsia had a value within 1 SD of the mean of the control group. It is suggested that the measurement of whole blood viscosity may be clinically useful in the management of patients with preeclampsia.

Labour-onset pre-eclampsia.

In a consecutive series of 1,201 singleton pregnancies with pre-eclampsia, the onset occurred during labour in 290 (24.1%). There was no difference between the primiparous and parous patient in this respect (25.9% v 20.7%; P less than 0.10). The tendency for pre-eclampsia to develop during labour increased with advancing maturity of the pregnancy and seldom occurred before 38 weeks of gestation; this was again equally true of the primiparous and parous patient, as was the incidence of severe hypertension (diastolic pressure greater than 110mm Hg) (36.1% v 34.1%). The high incidences of severe hypertension (35.5%), proteinuria (41.7%), and eclampsia (2.1%), and the 1 maternal death testified to the severity of the disease process and the need for aggressive management. After delivery, the clinical signs tended to subside rapidly, but the early third stage of labour was a time of maternal risk, irrespective of whether ergometrine or Syntocinon was the oxytocic agent administered. Analysis of perinatal results showed that the risk to the fetus was minimal.

Fetal growth retardation and pre-eclampsia.

In a series of 2434 patients with pre-eclampsia, the prevalence of fetal growth retardation was 8.7 per cent compared with 8.6 per cent in the total hospital population. The prevalence was increased in early-onset pre-eclampsia (18.2 per cent) (P less than 0.001) and reduced in late-onset pre-eclampsia (5.6 per cent) (P less than 0.001). In patients who later developed early-onset pre-eclampsia with fetal growth retardation, the prevalence of subnormal oestriol excretion was significantly increased (79.5 per cent) (P less than 0.001) as was the prevalence of hypoglycaemia (33.3 per cent) (P less than 0.001) suggesting that fetal growth retardation in these pregnancies preceded the clinical signs of pre-eclampsia. The prevalence of placental abruption (8.3 per cent) and the prevalence of perinatal deaths (28.7 per cent) were both significantly higher in pregnancies with early-onset pre-eclampsia and fetal growth retardation (P less than 0.001).

Parity and pre-eclampsia.

In a series of 26,209 patiens, the incidence of pre-eclampsia was 9.3%, being significantly higher in primiparae (14.1%) than multiparae (5.7%) (P less than 0.001). In patients with early-onset pre-eclampsia there were highly significant (P less than 0.001) increases in the incidences of proteinuria, severe hypertension, placental abruption, fetal growth retardation, neonatal asphyxia and perinatal mortality. There were no significant differences between the incidences of these complications in primiparae and multiparae. The incidence of subnormal oestriol excretion was increased before the emergence of early-onset pre-eclampsia with equal to significance (P less than 0.001) in primiparae and multiparae. Eclampsia was more common in patients with late-onset pre-eclampsia, but not significantly so.

Fetal growth and placental function assessed by urinary estriol excretion before the onset of pre-eclampsia.

In a series of 1,316 patients with pre-eclampsia 744 had urinary estriol excretion measured before and 366 after the onset of clinical signs of the disease. Low estriol excretion had a highly significant association with fetal growth retardation and perinatal death both before and after the onset of clinical signs (p less than 0.001). As assessed by the incidences of low estriol excretion, fetal growth retardation, and perinatal wastage, pre-eclampsia of early onset (before 37 weeks) was a malignant disease in comparison with pre-eclampsia of late onset (after 37 weeks). Patients destined to develop early-onset pre-eclampsia had a high incidence of subnormal estriol excretion (25.4%; p less than 0.001). Although further deterioration of placental function occurred after the onset of clinical signs (41.3%; p less than 0.01), fetal growth and prognosis were already determined.

Importance of abnormal glucose tolerance (hypoglycaemia and hyperglycaemia) in the aetiology of pre-eclampsia.

In a series of 794 patients who had glucose tolerance tests done before the onset of pre-eclampsia, both hypoglycaemia (less than 5th percentile) and hyperglycaemia (P less than 95th percentile) had a significant association with early-onset severe pre-eclampsia ( less than 0.05). In the total series of 794 patients, hypoglycaemia had a significant association with low oestriol excretion (p less than 0.01), fetal growth retardation (p less than 0-05), low Apgar score (p less than 0.05), and perinatal mortality (p less than 0.05). These data indicate that, in patients with pre-eclampsia, hypoglycaemia is directly related to the cause of perinatal death.

Marek's Disease Herpesviruses I. Production and Preliminary Characterization of Marek's Disease Herpesvirus A Antigen.

A method was developed for the large-scale production of Marek's disease herpesvirus A antigen in duck embryo fibroblast roller bottle cultures in quantities sufficient to permit its purification and characterization. Maximum yield was obtained in serum-free culture medium harvested daily. The Marek's disease herpesvirus A antigen was stable at pH 2.0 and was a glycoprotein based on its sensitivity to trypsin, specific immune co-precipitation of radioactive amino acids and glucosamine, and detection of radioactive glucosamine by immunodiffusion and autoradiography. The antigen aggregated and lost titer upon storage but dissociated readily and regained titer in 1 or 2 M urea and 0.05% Brij 35. Fresh unaggregated antigen or antigen dissociated with urea and Brij 35 sedimented at 3.7S on sucrose gradients. The apparent molecular weight of the glycoprotein antigen was estimated to be 44,800 by gel filtration on Sephadex G-200 in the presence of 2 M urea and 0.05% Brij 35.

Marek's Disease Herpesviruses II. Purification and Further Characterization of Marek's Disease Herpesvirus A Antigen.

Marek's disease herpesvirus A antigen was purified greater than 200-fold with a 24% recovery by ion exchange column chromatography, isoelectric focusing, and preparative polyacrylamide gel electrophoresis. The antigen had an isoelectric point of 6.68 +/- 0.03 in the presence of 1 M urea and 0.05% Brij 35, a nonionic detergent, and approximately 6.5 in the absence of dissociating agents. When analyzed by electrophoresis on analytical polyacrylamide gels, the purified antigen migrated as a single broad band which stained for both protein and carbohydrate, suggesting that it was a highly purified heterogeneous glycoprotein. However, the antigen was not purified to homogeneity as determined by electrophoresis on polyacrylamide gels in the presence of sodium dodecyl sulfate and by immunodiffusion analysis. Antibody to Marek's disease herpesvirus A antigen was prepared in a rabbit, and antibody to two contaminating antigens was removed by adsorption to yield monospecific antisera.

Delayed hypersensitivity and leucocyte migration inhibition in chickens with BCG or Marek's disease infection.

Production of Migration Inhibition Factor in vitro by lymphocytes from chickens with delayed hypersensitivity was examined. Chickens were sensitized with Bacille Calmette-Guerin (BCG) and others with Marek's Disease (MD) virus. Peripheral blood was used as a source of cells for in vitro radial migration inhibition. Using purified Band 24 antigen from Mycobacterium bovis and >>A<< antigen from MD virus, migration inhibition was demonstrated in BCG and MD sensitized chickens respectively, and not in controls. Results correlated well with intra-dermal skin reactions. Old Tuberculin and crude MD antigens inhibited radial migration of leucocytes from control chickens. The use of peripheral blood as a source of lymphocytes facilitates repeated sampling, both prior to and following sensitization. As a result, the role of the bursa and thymus in the induction and maintenance of delayed hypersensitivity can be studied in vitro. Furthermore, the role of cellular immunity and humoral antibodies as contributors to oncogenicity and/or protection in MD can be examined.