Antigen-associated immunosuppressant: effect of serum on immune response.

Serum from various animal species, including the test animals themselves, inhibits the antibody response of the rabbit to two bacterial antigens, provided that antigen and immunosuppressant interact prior to injection. The degree of immunosuppression is related to the length of incubation in vitro of antigen and serum. Serum does not hinder or destroy the antigenic determinant. Bacterial antibodies do not account for inhibition of the antibody response. Antigen-associated serum components, as yet unidentified, may affect the early events of the immune response.

Mucopolysaccharide from patients with cystic fibrosis of the pancreas.

Physical and immunologic methods were used to demonstrate the presence of an apparently unique glycoprotein in stool and tissue of patients having cystic fibrosis of the pancreas. The detection of a molecular structure specific for the disease is consistent with the apparent hereditary nature of the affection.

Relationship between the magnitude of bacteremia in children and the clinical disease.

The relationship between the magnitude of bacteremia due to Haemophilus influenzae, Streptococcus pneumoniae, and Neisseria meningitidis and the clinical diagnosis was determined on 79 children who were not receiving prior antibiotic therapy and had fever, either in the presence or absence of focal signs of infection. Bacteremia was quantitated by the recently described Quantitative Direct Plating procedure in which heparinized blood (0.5 ml each) is plated onto blood and chocolate agar plates. Additionally, blood was cultured by means of the radiometric Bactec technique. In the case of H. influenzae and S pneumoniae, 23 (92%) of 25 patients with more than 100 organisms per milliliter of blood had meningitis or epiglottitis in contrast to only four (9.5%) of 42 patients with less than 100 organisms (P less than .001). No significant difference was noted in the magnitude of bacteremia due to N meningitidis among 12 patients with meningitis or other serious infections. The possible predictive value of the quantitation of bacteremia is illustrated by the observation of three children with seemingly mild respiratory infection and counts in excess of 100 organisms per milliliter who, within 20 hours, developed meningitis or epiglottitis. High bacterial counts of H influenzae and S pneumoniae in excess of 100 organisms per milliliter of blood should alert the physician to the existence or possible development of serious disease.

Pasteurella multocida infection of urinary tract in patient with ileal loop.

Pasteurella multocida infection in the ileal loop and in the pelvis of a hydronephrotic kidney of a patient whose other kidney had been removed at age six months was documented by the repeated isolation of this patthogen. Two episodes occurred, the first terminated after a dose of gentamicin and the other without chemotherapy. Since the patient prior to infection was in severe renal failure necessitating hemodialysis, the effect of this infection on renal function could not be ascertained. The probable source was a cat present in the household.

The effects of prolonged retention of diaphragms on colonization by Staphylococcus aureus of the lower genital tract.

To determine whether prolonged retention of diaphragms alters Staphylococcus aureus colonization of the lower genital tract, 183 nonpregnant, asymptomatic women were screened for the presence of this pathogen in the cervix and upper vagina. Nineteen (10.4%) had positive cultures: 5 from the vagina, 8 from the cervix, and 6 from both sites. A second examination with quantitation revealed the presence of S. aureus in 7 of the 19 patients. In five of the six available patients, the number of staphylococci increased significantly after prolonged (24 hour) retention of diaphragms and decreased in one subject only. In two additional patients S. aureus was recovered after, but not before, the use of diaphragms. An increase in the number of other microorganisms also was noted after prolonged retention of diaphragms. In vitro study of the spermicide nonoxynol-9 revealed that it had no inhibitory activity on staphylococci or group B streptococci but was highly effective against Streptococcus pneumoniae.

Reconciling competing motives in self-evaluation: the role of self-control in feedback seeking.

On the basis of the assumption that positive experiences enhance perceived ability to cope with the discomfort associated with negative performance feedback (NF), it was hypothesized that (a) positive experiences increase willingness to accept negative but useful feedback and that (b) individuals seek positive experiences before accepting NF. Experiment 1 found that past success increased Ss' interest in unrelated NF. Experiment 2 found that positive mood increased Ss' interest in NF. Experiment 3 investigated the amount of time Ss spent reading about their past success while waiting for new feedback. When the new feedback was mandatory, the time Ss spent reading about their past success increased with the anticipated negativity of the new feedback. However, when the new feedback was optional, the time Ss spent reading about their past success was an inverted-U function of the anticipated negativity of the new feedback. Results are discussed in terms of self-control processes.

The gradient in mammography screening behavior: a lifestyle marker.

The study reports a gradient in adhering to a recommended health behavior-mammography screening. Data were collected on 951 Israeli women, aged 50-74, who were mailed an invitation to a prescheduled mammography screening appointment and were later phone interviewed about their background, their other health behaviors and their health perceptions related to cancer, mammography and self-rated health. The main finding that emerged was a gradient consisting of three groups defined by their adherence to mammography screening: women who declined the invitation to undergo screening (nonattenders, 32%), women who attended a screening upon encouragement (attenders, 45%) and women who initiated the test on their own (self-screenees, 23%). This gradient was shown to be related to structural/background variables (e.g. SES, age, education, ethnicity), other health behaviors and perceptual variables related to health in general and to cancer. For example, self-screenees were of a higher SES, engaged in more health behaviors and were closer to other women who performed a mammography. An analysis carried out to discern where the difference between the three groups lied showed that it was more apparent between the self-screenees and attenders, and that the attenders and nonattenders were more similar to each other. These findings are discussed in terms of health behavior as a discrete phenomenon vs. reflecting a lifestyle. Suggestions for intervention possibilities are presented in light of the finer ranking proposed above (as opposed to the dichotomy of engaging/not engaging in a health behavior).

The role of coagulase-negative staphylococci in chronic otitis media with effusion.

Twenty-eight middle ear effusions from 27 patients with chronic otitis media with effusion were studied for the presence of bacteria. The most common isolates were coagulase-negative staphylococci. However, biochemical and antibiotic sensitivity patterns demonstrated that these organisms represented a heterogenous group. At least three subtypes of coagulase-negative staphylococci were identified from the middle ear effusions, and in only one instance was the isolate from the ear canal identical with that of the middle ear effusion. The data presented suggest that coagulase-negative staphylococci from the middle ear effusions may not be contaminants; however, it cannot be determined from this study whether these organisms play a role as pathogens or as the result of indolent colonization.

Enteropathogenicity: recent developments.

Recent studies have added important new information to our understanding of the pathogenesis and ethiology of diarrheal disease. Vibrio cholerae produces a heat-labile enterotoxin, affecting cyclic AMP. A very similar heat-labile enterotoxin is produced also by certain strains of Escherichia coli, as well as by Citrobacter, Klebsiella, and Aeromonas. E. coli may also produce a heat-stable enterotoxin, stimulating guanylate cyclase activity. In order to produce the pathologic effects, E. coli first attaches to epithelial cells of the intestinal tract by means of pili or surface antigens. Enterotoxin can be demonstrated by both in vivo and in vitro tests, but none are yet suitable for routine diagnostic laboratories. A third mechanism whereby E. coli causes diarrheal disease consists of enteroinvasiveness. Campylobacter, Yersinia, and Clostridium difficile have been added to the list of enteric pathogens of man.

Production of common antigen by enteric bacteria grown in a synthetic culture medium.

Enterobacteriaceae share a common antigen (CA). The present investigation was carried out to determine whether this antigen is produced by representative strains of Escherichia, Salmonella, and Serratia grown in a completely synthetic medium. For comparative purposes, antigen production by the same strains grown in infusion broth was determined. CA, as assayed by indirect hemagglutination and immunogenicity studies in the rabbit, was produced by the microorganisms cultured in both media. The amount of CA produced by the strains varied according to the size of microbial population and to the length of culture. With the exception of E. coli O14, the strains studied, on day 7, produced 1.4 to 8 times more CA in infusion broth than in the synthetic medium; with E. coli O14, the ratio of CA in the respective media was 96:1. E. coli O14, but not E. coli O111 or S. typhimurium, when grown in the synthetic medium, engendered CA antibodies upon intravenous injection into rabbits. Ethanol extraction of the latter two strains yielded an immunogenic ethanol-soluble antigen preparation. The ethanol-soluble fraction of E. coli O111 also induced a secondary response in animals primed with E. coli O111 or S. typhimurium cultures grown in the synthetic medium. It is concluded that CA produced in a completely synthetic culture medium has the same attributes as CA produced in infusion broth.