Gender difference in cytokine secretion on immune stimulation with LPS and LTA.

Immune defense capacity differs between men and women. Whereas men are more prone to infection and sepsis, women more commonly develop autoimmune diseases. We investigated the difference in cytokine secretion between males and females in response to different immune stimuli. Whole blood from 154 healthy volunteers (age 24 +/- 5.2; 82 females, 72 males) was collected within 2 h on 2 consecutive days. Blood from males produced significantly more tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6, and IL-8 than blood from females in response to a high concentration of either lipopolysaccharide (LPS) or lipoteichoic acid (LTA), whereas IL-10 and interferon-gamma (IFN-gamma) secretion did not differ. Normalization of cytokine measurement to individual monocyte counts cancelled these differences for all parameters except TNF-alpha. Stimulation with a lower concentration of LPS (100 pg/mL) produced even stronger differences in cytokine release, which were not cancelled by normalization to the producing cells. The coefficients of variation (CV) of the LPS-induced and LTA-induced cytokine responses were higher in blood from women than men for all parameters and stimuli measured. Thus, the stronger innate immune response of males in comparison to females appears to stem not only from a difference in monocyte counts but also from the steepness of the response curve.     

Microbiological analyses and inflammatory effects of settled dusts from rice and hay

Fourteen samples of settled dust from two factories processing rice and wheat straw near Shanghai, China, were examined by dilution plating for total bacteria, gram-negative bacteria, thermophilic actinomycetes, and fungi. They were also examined for aflatoxin, endotoxin, and potential to stimulate production of human interleukin 1 beta (IL-1 beta) and to consume complement. The concentrations of total microorganisms were consistently greater than 10(7) CFU/g and ranged from 10(7) to 10(9) CFU/g. In general, the level of microbial contamination was greater in the hay dust samples than in the rice dust samples, with bacteria being the most numerous microorganisms observed followed by molds, thermophilic actinomycetes, and yeasts. The predominant fungi were species of Aspergillus, Cladosporium, Penicillium, Trichosporon, and Cryptococcus. No significant levels of aflatoxin were observed and the isolates of A. flavus examined lack significant aflatoxigenic potential. The levels of microorganisms in these samples, the types of organisms found, and the inflammatory mediators such as endotoxin suggest that workers exposed to these dusts may be at risk for respiratory illness.     

Increasing participation by private physicians in the EPSDT Program in rural North Carolina.

This study evaluated a method to increase physicians' participation in Early and Periodic Screening, Diagnosis and Treatment (EPSDT), a preventive health care program for Medicaid eligible children. Use of EPSDT can improve children's health status and reduce health care costs. Although the potential benefits of EPSDT are clear, the program is underused; low rates of participation by private physicians contribute to underuse. This study targeted a population of 73 primary care physicians in six rural counties in North Carolina where the physician supply, their participation in EPSDT, and use of EPSDT were low. A mailed intervention packet attempted to address barriers to participation perceived by private providers. The packet consisted of a carefully constructed letter, an informative journal article, and an educational pamphlet. Participation in EPSDT screening increased from 15 to 25 private physicians (67 percent), at a cost, on average, of less than $30 per recruited provider. Suggestions are presented for adapting the intervention packet to other settings.     

Risk-Taking among Adolescents Who Say They Can Get a Handgun

In a survey of 5657 community-residing adolescents, those who said they could get a handgun in two days reported similar and those who said they could not get a handgun reported fewer risk behaviors and less violence perpetration and victimization than adolescents who have their own handgun. Adolescents who said they could get a handgun reported more exposure to and experience with firearms than those who said they could not get a handgun. Risk reduction efforts regarding adolescents should be expanded to include adolescents who say they can get a handgun.     

The effects of carbamazepine on stuttering.

No pharmacological treatment protocol has proven generally useful for all patients who stutter. Various medications, behavior therapy, relaxation, suggestion, and social-based therapies have been used. For this drug treatment study, two groups of adult stutterers were followed in an 8-week open label protocol. All subjects had in the past received speech therapy; none had been treated previously with medication for stuttering. The first group (N = 12) received a maximum dose of 800 mg of carbamazepine; the second group (N = 8) received a maximum dose of 400 mg of carbamazepine. Each patient served as his or her own control. A series of systematic speech tests was given weekly to determine the variability of fluency for each subject. A statistically significant change occurred for a number of "expectancy to stutter" characteristics. Subjects felt that they stuttered less often while taking carbamazepine. Subjective effects began before medication and continued after patients discontinued the medication. Struggle characteristics also subjectively decreased. However, no objective improvement was found. No change was found in percentage of words stuttered, reading improvement, or improvement in spontaneous speech rate. Interrater reliability showed a correlation of .996. Three carbamazepine serum level therapeutic windows were inspected with negative results. Interestingly, naive listener ratings did show a statistically significant improvement on carbamazepine versus placebo. Future anecdotal reports of pharmacological improvement of stuttering should be subjected to rigorous objective testing before general acceptance.     

Functional substitution of the TibC protein of enterotoxigenic Escherichia coli strains for the autotransporter adhesin heptosyltransferase of the AIDA system

The plasmid-encoded AIDA (adhesin involved in diffuse adherence) autotransporter protein derived from diffuse-adhering clinical Escherichia coli isolate 2787 and the TibA (enterotoxigenic invasion locus B) protein encoded by the chromosomal tib locus of enterotoxigenic E. coli (ETEC) strain H10407 are posttranslationally modified by carbohydrate substituents. Analysis of the AIDA-I adhesin showed that the modification involved heptose residues. AIDA-I is modified by the heptosyltransferase activity of the product of the aah gene, which is located directly upstream of adhesin-encoding gene aidA. The carbohydrate modification of the TibA adhesin/invasin is mediated by the TibC protein but has not been elucidated. Based on the sequence similarities between TibC and AAH (autotransporter adhesin heptosyltransferase) and between the TibA and the AIDA proteins we hypothesized that the AIDA system and the Tib system encoded by the tib locus are structurally and functionally related. Here we show that (i) TibC proteins derived from different ETEC strains appear to be highly conserved, (ii) recombinant TibC proteins can substitute for the AAH heptosyltransferase in introducing the heptosyl modification to AIDA-I, (iii) this modification is functional in restoring the adhesive function of AIDA-I, (iv) a single amino acid substitution at position 358 completely abolishes this activity, and (v) antibodies directed at the functionally active AIDA-I recognize a protein resembling modified TibA in ETEC strains. In summary, we conclude that, like AAH, TibC represents an example of a novel class of heptosyltransferases specifically transferring heptose residues onto multiple sites of a protein backbone. A potential consensus sequence for the modification site is suggested.     

Molecular analysis of the short arm of chromosome 3 in small-cell and non-small-cell carcinoma of the lung

Previous studies have suggested that the loss of DNA sequences on the short arm of chromosome 3 (3p) is associated with small-cell lung carcinoma. We therefore looked for loss of 3p alleles in tumor tissue from 42 patients with either small-cell or non-small-cell lung carcinoma. All 13 patients with small-cell lung carcinoma who were heterozygous for one or more alleles at 3p in normal tissue had the loss of at least one codominant allele in the tumor tissue. Cell lines of small-cell lung carcinoma from an additional eight patients were homozygous for 3p alleles; this result was significantly different from the predicted frequency of homozygosity. The tumor tissue studied included cell lines of small-cell lung carcinoma obtained from biopsy specimens, an autopsy sample, and an excised lymph node containing tumor cells. Loss of alleles at 3p was observed in tumor samples obtained before and after chemotherapy. Four of 15 evaluable patients with non-small-cell carcinoma of the lung had loss of 3p alleles. We conclude that loss of alleles at 3p is a change found consistently in small-cell lung carcinoma and occasionally in non-small-cell lung carcinoma.     

Attenuated poxvirus expressing three immunodominant CMV antigens as a vaccine strategy for CMV infection.

BACKGROUND: Human cytomegalovirus (CMV) infection is an important risk factor in the post-transplant (Tx) recovery phase for both hematopoietic stem cell Tx (HSCT) and solid organ Tx (SOT) recipients. CMV infection may be prevented or controlled by simultaneously inducing both CMV-specific neutralizing antibody (nAb) and cellular immunity. Soluble (s) UL55 (surface glycoprotein), UL83 (tegument protein) and UL123/e4 (nuclear protein) are immunodominant in eliciting both CMV nAb and cellular immunity. An attenuated poxvirus, modified vaccinia Ankara (MVA) was selected to develop this vaccine strategy in Tx recipients, because of its clinical safety record, large foreign gene capacity, and capability to activate strong humoral and cellular immune responses against recombinant antigens. OBJECTIVES: A subunit vaccine that targets multiple CMV antigens will be used to gain maximal coverage and protective function against CMV infection. rMVA simultaneously expressing sUL55, UL83 and UL123/e4 will be generated, and humoral and cellular immunity it elicits will be characterized, after murine immunization and in vitro to amplify clinical recall responses. STUDY DESIGN: rMVA will be constructed in two steps using UL123/e4-pLW22 followed by sUL55-UL83-pLW51 transfer plasmids. Western blots will be used to characterize expression levels of each antigen. Primary immunity will be evaluated in mouse models, while recall responses to the virally expressed CMV antigens will be assessed in human peripheral blood. RESULTS: We generated CMV-MVA via homologous recombination, and demonstrated high expression levels of sUL55, UL83 and UL123/e4 by Western blot. CMV-MVA immunization potently induced both humoral and cellular immunity to sUL55, UL83 and UL123 after murine immunization, and cellular immunity to UL83 and UL123 by in vitro amplification of T cell recall responses in human PBMC. CONCLUSIONS: rMVA promotes high level expression of three immunodominant CMV antigens, which is reflected in results of immunization studies in which high titers of UL55-specific antibodies and CD4+ T-help are detected, as well as high levels of UL83-specific and moderate levels of UL123-specific CD8+ CTL.     

Morphologic and Functional Characteristics of Long-Term Cultures of Murine Myeloma Cells

Although permeation of capillary endothelia by horseradish peroxidase has been related to the presence of narrow channels between cells, junctions between endothelial cells in the aorta contain extensive regions that are occluded by apposition or fusion of the adjacent plasma membranes. Despite this, intravenously infused horseradish peroxidase rapidly appears within both the endothelial cell junctions and the microvesicles and caveoli. This suggests that the enzyme may arrive in the junctional space by some route other than passage between the endothelial cells. One possibility is vesicular transport from the lumen to the junctional cell surface. Alternatively, the occluded regions may represent only a partial permeability barrier, which either incompletely surrounds each cell in the manner of the maculae occludentes of epithelia, or leaves passages open between some cells while completely closing the perimeter of others. The aortic intima also differs from other vessel linings in having a reticular form of basement membrane. The structural role of this reticulum in supporting the endothelium remains undetermined as does its effect on premeability of the intima.     

Polarized expression of Na+/H+ exchange activity in LLC-PK1/PKE20 cells: II. Hormonal regulation

LLC-PK₁/PKE₂₀ cells (a continuous epithelial cell line) has two different Na/H exchange activities: Na/H-1 located in the basolateral membrane and Na/H-2 located in the apical membrane [Casavola et al. (1989) Biochem Biophys Res Commun 165:833–837; Haggerty et al. (1988) Proc Natl Acad Sci USA 86:6797–6801]. In the present report we have studied hormone regulation of these exchange activities by measuring Na-dependent recovery of pH_i from an acid load (by using microspectrofluorometry and 2,7-bis(carboxyethyl)-5,6-carboxyfluorescein) in response to activation of regulatory cascades by either pharmacological agents or by vasopressin or calcitonin. Agents leading to activation of protein kinase A (cAMP-dependent), such as forskolin (10 M), 8-Br-cAMP (0.25 mM), and isobutylmethylxanthine (0.5 mM), inhibited Na/H-2 and Na/H-1 by an average of 49%. Stimulation of protein kinase C by a phorbol ester (phorbol 12-myristate 13-acetate, TPA, 100 nM) inhibited Na/H-2 (by an average of 48%) and stimulated Na/H-1 (by an average of 38%); these effects of TPA were also observed in the presence of forskolin (100 M). Addition of either vasopressin (2 M) or calcitonin (0.3 M) onto both sides of the monolayer decreased the activity of Na/H-2 by an average of 26.3% and 27.7% respectively, and stimulated the activity of Na/H-1 by an average of 17.4% and 38.7% respectively; exposure of cells to either hormone stimulated production of cAMP and inositol trisphosphate, respectively. Separate hormone additions to either the apical or basolateral cell surface led to effects similar to those produced by simultaneous hormone additions onto both cell surfaces, although the relative response of Na/H exchangers to either agonist is variable. In summary, these results suggest that in LLC-PK ₁/PKE₂₀ cells, vasopressin and calcitonin can act via receptor systems coupled either to adenylate cyclase or to phospholipase C. Activation of these receptor systems can lead to inhibition of Na/H-2 and stimulation of Na/H-1.