A comparison study of human papillomavirus prevalence by the polymerase chain reaction in low risk women and in a gynaecology referral group at elevated risk for cervical cancer.

The reported prevalence of human papillomavirus (HPV) type 16 in the genital tracts of women with various gynaecological conditions is highly variable. In particular, some results with the polymerase chain reaction (PCR) technique have suggested that HPV-16 is a ubiquitous or very common virus. We undertook this study to help clarify the current confusion. PCR with HPV consensus L1 primers and specific E6 primers was used to study 89 women attending two gynaecology referral clinics, as well as 99 women attending a health maintenance organization (HMO) clinic; 70 of these latter women had no current or prior history of genital HPV disease. HPV-16 was detected in less than 5% of cytologically normal women from either group and in 17% (6/36) and 31% (9/29) of women with cervical intraepithelial neoplasia (CIN) from the referral clinic and the HMO, respectively. The other high-risk or intermediate-risk HPVs (types 18, 31, 33 or 35) were less prevalent than HPV 16 in all groups of women. A majority of the HPV types detected by the L1 primers in normal women were uncharacterized HPVs. Overall these uncharacterized HPVs were detected in 37% (46/123) of the normal women and in 48% (31/65) of the women with CIN. Using the most sensitive PCR product detection method employed in the study, HPV DNA was detected in 36% (4/11) of swab specimens obtained from the external abdomen.     

Pitfalls in counselling: the craniosynostoses.

We describe three families to highlight the variability of expression and penetrance that can occur in the craniosynostoses. In two of the families, gene carriers were only identified in retrospect by looking at photographs of other family members. In the third family, identical twins were initially thought to be discordant for sagittal craniosynostosis until early skull x rays were examined and both were found to be affected. The dilemmas faced when counselling these families are discussed.     

Reasons students give for limiting drinking: a factor analysis with implications for research and practice

Dimensions of cognitions associated with self-regulation of alcohol consumption were studied using a 22-item Reasons for Limiting Drinking (RLD) scale in a student survey of nine universities. Data on 2,482 drinkers were factor analyzed using several methods in split halves and the total sample. Four interpretable factors accounting for 39% of the common variance were consistently found. Based on core content, these subjective motivational factors were labeled self-control, upbringing, self-reform and performance. Reliability analysis was used to construct subscales to assess these factors. Subscales had adequate internal reliability (alphas = .66-.73) for brief research scales. Relationships between the RLD subscales and between these subscales and selected demographic, alcohol-consumption and problem indicators are summarized. Based on these results and an application in a prevention experiment with heavily drinking students, the niche for such "reasons" measures in participant screening and program evaluation is discussed.     

Pulmonary toxicity of trichloroethylene: induction of changes in surfactant phospholipids and phospholipase A2 activity in the mouse lung

Trichloroethylene (TCE) is a common organic solvent in use as a dry cleaning agent as well as an inhalant anesthetic. Nevertheless the effects of this material on the pulmonary surfactant which prevents alveolar collapse at maximal expiration is not known. Therefore, we have examined the effect of TCE on the intra- and extracellular surfactant pools and the activity of phospholipase A2, an enzyme which controls the remodeling of phosphatidylcholine to dipalmitoylphosphatidylcholine, the primary constituent of the pulmonary surfactant. Male CD-1 mice were treated ip with 2500 or 3000 mg/kg TCE. Twenty-four hours later mice were anesthetized and the lungs lavaged. Mice were then killed, the lungs perfused and excised, and subcellular fractions including lamellar bodies prepared. Some lungs were prepared for ultrastructural examination. Phospholipase A2 was assayed in all subcellular fractions. Phospholipid was assayed in the lavage (extracellular surfactant) and the lamellar bodies (intracellular surfactant). TCE (2500 mg/kg) caused selective exfoliation of Clara cells. However, only the dose of 3000 mg/kg TCE produced a significant decrease in the intracellular surfactant phospholipid. Minimal changes occurred in the phospholipid profiles. Phospholipase A2 specific activity was significantly decreased at both dosages within the lung microsomal fraction. In addition after treatment with 3000 mg/kg TCE the enzyme activity in the lamellar body fraction was significantly increased. These data suggest that inhalation of TCE may damage the enzymes which are responsible for synthesizing the pulmonary surfactant resulting in lower amounts of surfactant being stored and available for secretion into the alveolus.     

Stimulation of β-adrenoceptors inhibits store-operated channel currents via a cAMP-dependent protein kinase mechanism in rabbit portal vein myocytes

Previously we have described the properties of store-operated channel currents (SOCs) in freshly dispersed rabbit portal vein smooth muscle cells. In addition to Ca²⁺ store depletion these SOCs could also be activated by α-adrenoceptor stimulation and diacylglycerol (DAG) via a protein kinase C (PKC)-dependent mechanism. In the present study we have investigated the effect of β-adrenoceptor stimulation on SOCs in rabbit portal vein myocytes. With whole-cell recording the selective β-adrenoceptor agonist isoprenaline reduced the current evoked by cyclopiazonic acid (CPA, sarcoplasmic/endoplasmic reticulum ATPase inhibitor) by over 85%. With cell-attached patch recording, bath application of isoprenaline produced a pronounced inhibition of SOC activity evoked by either CPA or the acetoxymethyl ester form of BAPTA (BAPTA-AM). SOC activity evoked by CPA, the DAG analogue, 1-oleoyl-acetyl- sn -glycerol (OAG) or the phorbol ester, phorbol-12,13-dibutyrate (PDBu) was also markedly inhibited by the adenylate cyclase activator, forskolin, and the cell-permeable non-hydrolysable analogue of cyclic adenosine monophosphate (cAMP), 8-Br-cAMP. With inside-out patches, bath application of PDBu evoked channel currents with similar properties to SOCs which were inhibited by over 90% by a catalytic subunit of protein kinase A (PKA) and by 8-Br-cAMP. Moreover bath application of PKA inhibitors, H-89, KT5720 and an inhibitory peptide to quiescent cell-attached or inside-out patches, activated channel currents with similar properties to SOCs. These data suggest that in rabbit portal vein myocytes, stimulation of β-adrenoceptors inhibits SOC activity via a cAMP-dependent protein kinase signal transduction cascade. In addition it is concluded that constitutive PKA activity has a profound inhibitory effect on SOC activity in this vascular preparation.     

The effects of indoramin on histamine and antigen-induced changes in respiration in guinea-pigs

Indoramin, a drug which blocks alpha-adrenergie, histamine and serotonin receptors, was tested as a protective agent during challenge with bronchoconstrictor agents in guinea-pigs. In conscious guinea-pigs, the time of onset of respiratory distress during continuous administration of aerosolized solutions of histamine, serotonin or ovalbumin (with animals pre-sensitized to this antigen) was measured using a force-displacement transducer applied to the animal's back. This time interval for each guinea-pig was compared with and without indoramin pre-treatment. Indoramin was administered by intraperitoneal injection or by aerosol treatment. In anaesthetized animals under artificial respiration, respiratory distress was induced by intravenous injection of histamine and measured by the Konzett-Rössler technique. Indoramin treatment significantly protected guinea-pigs in both types of experiment from the effects of each challenging agent.     

Use of bacteriophage Ba1 to identify properties associated with Bordetella avium virulence

Bordetella avium causes bordetellosis, an upper respiratory disease of birds. Commercially raised turkeys are particularly susceptible. We report here on the use of a recently described B. avium bacteriophage, Ba1, as a tool for investigating the effects of lysogeny and phage resistance on virulence. We found that lysogeny had no effect on any of the in vivo or in vitro measurements of virulence we employed. However, two-thirds (six of nine) spontaneous phage-resistant mutants of our virulent laboratory strain, 197N, were attenuated. Phage resistance was associated, in all cases, with an inability of the mutants to bind phage. Further tests of the mutants revealed that all had increased sensitivities to surfactants, and increased amounts of incomplete (O-antigen-deficient) lipopolysaccharide (LPS) compared to 197N. Hot phenol-water-extracted 197N LPS inactivated phage in a specific and dose-dependent manner. Acid hydrolysis and removal of lipid A had little effect upon the ability of isolated LPS to inactivate Ba1, suggesting that the core region and possibly the O antigen were required for phage binding. All of the mutants, with one exception, were significantly more sensitive to naive turkey serum and, without exception, significantly less able to bind to tracheal rings in vitro than 197N. Interestingly, the three phage-resistant mutants that remained virulent appeared to be O antigen deficient and were among the mutants that were the most serum sensitive and least able to bind turkey tracheal rings in vitro. This observation allowed us to conclude that even severe defects in tracheal ring binding and serum resistance manifested in vitro were not necessarily indicative of attenuation and that complete LPS may not be required for virulence.     

Identification of mutations in TCOF1: use of molecular analysis in the pre- and postnatal diagnosis of Treacher Collins syndrome

Treacher Collins syndrome (TCS) is an autosomal dominant disorder of facial development, which results from mutations in TCOF1. TCS comprises conductive hearing loss, hypoplasia of the mandible and maxilla, downward sloping palpebral fissures and cleft palate. Although, there is usually a reasonable degree of bilateral symmetry, a high degree of both inter- and intrafamilial variability is characteristic of TCS. The wide variation in the clinical presentation of different patients, together with the fact that more than 60% of cases arise de novo, can complicate the diagnosis of mild cases and genetic counselling. In the current study, we describe how molecular techniques have been used to facilitate pre- and postnatal disease diagnoses in 13 TCS families.