Respiratory syncytial virus infection and virus-induced inflammation are modified by contaminants of indoor air

The airway epithelium is the first cellular component of the lung to be encountered by the particles and pathogens present in inhaled air. In addition to its role as a physical barrier, the immunological activity of the airway epithelium is an essential part of the pulmonary immune system. This means that the symptoms of lung diseases that involve immunological mechanisms are frequently exacerbated by infection of the airway epithelium with respiratory viruses. The virus-induced enhancement of immunological activity in infected epithelial cells is well characterized. However, the effects that contaminants of inhaled air have upon the infectivity and replication of respiratory viruses and the inflammation they cause, are comparatively unknown. In this study, we have shown that pre-exposure of airway epithelial cells to bacterial lipopolysaccharides or a proteolytically active house dust mite allergen, is able to, respectively, inhibit or enhance the level of cellular infection with respiratory syncytial virus and similarly alter virus-induced expression of the inflammatory chemokine interleukin-8. These results suggest that respiratory syncytial virus infection and the inflammation caused by respiratory syncytial virus may be modified by the biologically active contaminants of indoor air.     

Cloning, expression, and mapping of the Staphylococcus aureus alpha-hemolysin determinant in Escherichia coli K-12.

A fragment of Staphylococcus aureus DNA encoding the alpha-hemolysin determinant was cloned from strain Wood 46 by inserting Sau3A-generated genomic DNA fragments between the BamHI sites of the lambda replacement vector L47.1. Phages expressing alpha-hemolysin were detected by overlaying plaques formed from several thousand independent recombinant phage with erythrocytes and looking for zones of hemolysis. One phage expressing alpha-hemolysin was purified and named lambda w alpha 3. This was subsequently shown to contain a 10.2-kilobase pair insert of S. aureus DNA. A 7.6-kilobase pair HindIII fragment encoding the alpha-hemolysin was subcloned from lambda w alpha 3 into the plasmid vector pACYC184 to form the hybrid plasmid pDU1148. Escherichia coli K-12 cells harboring pDU1148 synthesized a low level of alpha-hemolysin which remained associated with the cells and was not secreted into culture supernatants. When the same strain was stabbed onto blood agar plates, no zones of hemolysis were detected after overnight growth at 37 degrees C but hemolysis developed if the plates were left at room temperature for 48 h. By introducing specific deletions or Tn5 insertions into plasmid pDU1148, the alpha-hemolysin gene was mapped to a region within a 3.3-kilobase pair EcoRI-HindIII fragment which was subcloned onto the vector plasmid pBR322. A specific enzyme-linked immunosorbent assay with peroxidase-labeled rabbit anti-alpha-hemolysin antibodies was used to measure the levels of alpha-hemolysin antigen expressed in E. coli K-12 cells harboring pDU1148 or a variety of pDU1148::Tn5 and pDU1148 deletion mutants.     

Norethisterone treatment to control timing of the IVF cycle

The use of norethisterone to control the timing of the precedingmenstrual cycle and in consequence the timing of the in-vitrofertilization (IVF) cycle has been evaluated in a therapeuticIVF programme in which oocyte recovery was limited to 2 dayseach week. A consecutive series of 181 cycles after norethisteroneand 29 untreated controls were compared. Menstruation occurred2– 3 days after norethisterone as planned in 82% of patientsoverall and in 87% of patients whose menstrual cycle lengthvaried by no more than 2 days about the median. Norethisteronetreatment did not significantly affect the outcome of IVF treatmentcompared with the controls in respect to cycles abandoned (12versus 0%, respectively), peak follicular diameter (mean 18.1mm versus 18.3 mm 48 h before laparoscopy), oocyte recoveryrate (4.6 versus 4.5 per patient), oocyte morphology (63% versus52% mature), or fertilization rate (72 versus 65% of matureoocytes). Clinical pregnancies were too few for comparison (rates27 versus 9% per laparoscopy) but the overall rate (23%) indicatedeffectiveness of the methods. Prior norethisterone treatmentappears to be an effective and useful means of controlling thetiming of the oocyte recovery in IVF treatment.     

Assessment of short-term visual memory in child and adolescent psychiatric inpatients

This study provides normative data on 270 child and adolescent psychiatric inpatients using the Bender Recall technique as a measure of short-term visual memory. In addition, the authors present normative data on another immediate recall technique using the Coding section of the WISC-R. These findings are examined in light of age differences and IQ scores. Detailed instructions for administering the Coding Recall technique are presented.     

Comparison of rapid,automated ribotyping and DNA macrorestriction analysis of Burkholderia pseudomallei

An automated ribotyping device (RiboPrinter) was used to determine the ribotypes of a collection of Burkholderia pseudomallei isolates. In a preliminary evaluation with the restriction enzymes BamHI and EcoRI, the protocol with EcoRI was more discriminating. The reproducibilities of the ribotypes obtained with EcoRI (EcoRI ribotypes) were determined by testing three levels of bacterial loads. The performance of the manufacturer's software was assessed by comparing the machine-optimized ribotypes with the type determined from the original gel image analyzed with Bionumerics software. The library of B. pseudomallei EcoRI ribotypes was then compared with the ribotypes obtained by DNA macrorestriction analysis of XbaI digests by pulsed-field gel electrophoresis. The typeability of B. pseudomallei by EcoRI ribotyping was 100%, and the discrimination index was 0.94. The slightly greater discrimination provided by DNA macrorestriction analysis (0.96) was achieved at the expense of a significantly longer processing time of 6 days, although the method was only half the cost of automated ribotyping. Typeability by macrorestriction analysis was lower (97%) unless a thiourea step was added to neutralize the action of Tris-dependent endonucleases. The digital record of B. pseudomallei isolates analyzed thus far provides a useful resource for future epidemiological studies and will help shorten the response time in the event of a further melioidosis outbreak or the deliberate release of B. pseudomallei as a biohazard.     

Virulence of protein A-deficient and alpha-toxin-deficient mutants of Staphylococcus aureus isolated by allele replacement.

The gene coding for protein A (spa) of Staphylococcus aureus 8325-4 has been inactivated by substituting part of the spa coding sequence for a DNA fragment specifying resistance to ethidium bromide. The in vitro-constructed spa::EtBrr substitution mutation was introduced into the S. aureus chromosome by recombinational allele replacement. Southern blot hybridization showed that the in vitro-constructed mutation was present in the chromosomal spa locus. We have previously reported the inactivation of the alpha-toxin gene (hly) by allele replacement with an in vitro-constructed hly::Emr (erythromycin resistance) mutation (M. O'Reilly, J.C.S. de Azavedo, S. Kennedy, and T.J. Foster, Microb. Pathogen. 1:125-138, 1986). A double Spa- Hly- mutant was constructed by transduction. The virulence of Spa- and Hly- mutants was tested by experimental infection of mice. When subcutaneous injections were given, Hly- mutants formed a flat, darkened lesion, whereas Hly+ strains caused a raised, cream lesion. Alpha-toxin was shown to be a major factor in forming subcutaneous lesions and in causing the death of mice injected intraperitoneally. Spa- mutants were slightly less virulent than their Spa+ counterparts, which suggests that protein A is also a virulence factor of S. aureus.     

Genetic studies on murine susceptibility to herpes simplex keratitis

We studied the influence of lgh-linked genes on the development of keratopathy after corneal inoculation with herpes simplex virus (HSV). Using congenic strains of mice, we found that the lgh-1 gene locus, or genes closely linked to it, influence the clinical expression of HSV infection. Mice with the lgh-1e or lgh-1d allotype routinely developed severe keratopathy after HSV corneal inoculation, whereas congenic strains with lgh-1a or lgh-1b allotype were less susceptible. Cell-mediated immune responses to HSV also differed between susceptible and resistant murine strains. We interpret our results to imply a genetic influence on cell-mediated, acquired immune responses to HSV infection.     

Correlates of body image dissatisfaction among overweight women seeking weight loss

Predictors of body image dissatisfaction (BID) among obese people are poorly understood. In 79 obese women seeking weight reduction, associations with BID of self-esteem, youth teasing, adult teasing, and internalization of sociocultural appearance standards (ISAS) were studied. Analyses revealed that only self-esteem, adult teasing, and ISAS predicted BID. Results highlight the importance of adulthood self-esteem and interpersonal-cultural context--rather than childhood experiences--in predicting adulthood BID.