Why valve opening pressure plays a relatively minor role in the postural ICP response to ventricular shunts in normal pressure hydrocephalus: modeling and implications.

OBJECTIVES: In normal pressure hydrocephalus, there is no clear evidence that the opening pressure of differential pressure valves influences outcome. In this study, the objective was to determine whether the relationship between valve opening pressure and post-operative postural ICP changes was predictable. METHODS: Eight adult-onset hydrocephalus patients were evaluated using an intraparenchymal ICP microsensor. Postural ICP measurements were obtained before and after placement of a ventricular shunt (VP or VA) with a Codman Hakim programmable valve. RESULTS: Valve opening pressure had a poor correlation with ICP at any head-of-bed elevation across subjects (best r = 0.25). The degree of negative ICP encountered for any given patient did not appear to be determined by the valve pressure, and varied significantly between patients at the same valve pressure. Each individual's ICP correlated well to opening pressure (r > 0.76), but the response is more sigmoidal than linear, and the opening pressure at which ICP changed most was markedly different between patients. CONCLUSIONS: The hydrodynamic pressures generated by shunts with different pressure valves are unpredictable. Our data supports the use of programmable valves in patients with adult onset hydrocephalus and suggests that ICP be measured post-operatively to achieve an optimal clinical outcome.

Virulence factors of Escherichia coli isolated from female reproductive tract infections and neonatal sepsis.

OBJECTIVE: The presence of enterobacteria such as Escherichia coli in the vagina of normal women is not synonymous with infection. However, vaginal E. coli may also cause symptomatic infections. We examined bacterial virulence properties that may promote symptomatic female reproductive tract infections (RTI) and neonatal sepsis. METHODS: E. coli isolated as the causative agent from cases of vaginitis (n = 50), tubo-ovarian abscess (n = 45) and neonatal sepsis (n = 45) was examined for selected phenotypic and genetic virulence properties. Results were compared with the frequency of the same properties among fecal E. coli not associated with disease. RESULTS: A significantly greater proportion of infection E. coli exhibited D-mannose resistant hemagglutination compared with fecal E. coli (p < 0.01). This adherence phenotype was associated with the presence of P fimbriae (pap) genes which were also significantly more prevalent among isolates from all three infection sites (p < 0.01). The majority of pap+ isolates contained the papG3 allele (Class II) regardless of infection type. Increased frequency of Type IC genes among vaginitis and abscess isolates was also noted. No significant differences in frequency of other bacterial adherence genes, fim, sfa, uca (gaf or dra were observed. E. coli associated with vaginitis was significantly more likely to be hemolytic (Hly+) than were fecal isolates (p < 0.05). The Hly+ phenotype was also more prevalent among tubo-ovarian abscess and neonatal sepsis isolates (p < 0.08). CONCLUSIONS: E. coli isolated from female RTI and neonatal sepses possess unique properties that may enhance their virulence. These properties are similar to those associated with other E. coli extra-intestinal infections, indicating that strategies such as vaccination or bacterial interference that may be developed against urinary tract infections (UTI) and other E. coli extra-intestinal infections may also prevent selected female RTI.

Production of IL-5 and granulocyte-macrophage colony-stimulating factor by naive human mast cells activated by high-affinity IgE receptor ligation.

BACKGROUND: The late-phase allergic reaction is an eosinophilic inflammatory response that begins several hours after allergen exposure, may persist for 24 hours, and is an important pathogenic mechanism in allergic disease. OBJECTIVE: Cultured naive human mast cells were used to investigate whether mast cells are a direct source of the eosinophil-promoting cytokines IL-5, IL-3, and granulocyte-macrophage colony-stimulating factor (GM-CSF). METHODS: Naive human mast cells were derived from bone marrow mononuclear cells cultured in the presence of stem-cell factor. Cytokine message and protein production in response to high-affinity IgE receptor ligation of cultured mast cells were measured by semiquantitative polymerase chain reaction and ELISA, respectively. RESULTS: IL-5, IL-3, and GM-CSF messenger RNA increased within 2 hours of mast cell activation, with IL-5 and GM-CSF message remaining elevated for 24 hours, whereas IL-3 mRNA rapidly declined. IL-5 and GM-CSF protein were measurable 4 to 6 hours after stimulation and peaked by 24 and 12 hours, respectively. IL-3 protein was not detectable. CONCLUSION: These findings demonstrate that naive mast cells do not constitutively produce IL-5 or GM-CSF protein but are a major source of these eosinophilotropic cytokines on high-affinity IgE receptor ligation.

Molecular cloning of Proteus mirabilis uroepithelial cell adherence (uca) genes.

Proteus mirabilis bacteria are a common cause of hospital-acquired urinary tract infection. In a previous study, we described a P. mirabilis fimbrial protein, UCA, that adhered to human uroepithelial cells. Genes sufficient for expression of UCA adherence were cloned into Escherichia coli K-12. E. coli bacteria that contained the uca recombinant plasmid adhered to human uroepithelial cells. In addition, the ucaA gene encoding the structural component of UCA pili was subcloned, and its DNA sequence was determined. Amino acid sequence homology (30 to 50%) was found between mature UcaA protein and pilins from pathogenic bacteria representing several genera, including E. coli F17, G, and type 1C pilins, Haemophilus M43 pilin, and a Bordetella pilin.

Men's self-reports of unwanted sexual activity.

We investigated men's experience with unwanted sexual activity-including unwanted kissing, petting, or intercourse-engaged in because of physical or psychological pressure or from societal expectations about male sexuality. We developed a questionnaire asking if respondents had ever engaged in unwanted sexual activity for any of 51 reasons. This questionnaire was administered to 507 men and 486 women. More women (97.5%) than men (93.5%) had experienced unwanted sexual activity; more men (62.7%) than women (46.3%) had experienced unwanted intercourse. Using factor analysis, we grouped the 51 questionnaire items into 13 general reasons; we then compared percentages of men and women who had engaged in unwanted sexual activity for these 13 reasons. There were seven sex differences in reasons for unwanted sexual activity: Five were more frequent for women than men; two reasons were more frequent for men than women-peer pressure and desire for popularity. There were eight sex differences in reasons for unwanted intercourse; more men than women had engaged in unwanted intercourse for all eight. The double standard for male and female sexuality and implications for therapy are discussed.

Nickel dermatitis: the reaction to oral nickel challenge.

Pompholyx in nickel-sensitive subjects can be induced by orally-administered nickel, but only by a high dose. Ingestion of 5.6 mg nickel consistently worsened the pompholyx, often with a mild toxic erythema or patch test site flare, but lower doses of nickel failed to excite reactions more frequently than did a placebo, in a double-blind study. The metabolism of nickel is complex and there was considerable variation between three normal individuals in their absorption and excretion of an orally-administered nickel load. Patients may show similar variability which could be of importance clinically, although in only one of five subjects with acute eczema was the serum nickel raised, and then only marginally. The exact role of dietary nickel in perpetuating the hand dermatitis of sensitive subjects remains unclear.

Conditioned autonomic responses as bidirectional indicators of racial attitude.

Present physiological techniques of attitude measurement tap attitude intensity but not attitude direction. An alternative physiological technique, based upon the phenomenon of semantic generalization of conditioned autonomic responses, was tested to determine whether it would provide a bidirectional indicator of attitude. Subjects with favorable or unfavorable self-reported attitudes toward blacks were conditioned to statements having no racial content which they had previously evaluated as "bad." Subsequently, they were presented with statements with racial content; the latter were sentences which would be differentially evaluated as "good" or "bad" by persons with dissimilar racial attitudes. It was hypothesized that racial attitude would predict conditioned autonomic responses elicited by the generalization statements. It was found that groups differing in racial attitude could be distinguished on the basis of their conditioned responses to the race-related generalization statements. Unresolved problems of interpretation are discussed.