Comparison of Southern transfer hybridization and dot filter hybridization for detection of cervical human papillomavirus infection with types 6, 11, 16, 18, 31, 33, and 35

A commercial dot filter hybridization kit (Virapap Kit) was compared with Southern transfer hybridization for the detection of seven types of human papillomavirus (HPV) in cervical specimens from 450 consecutive females attending a sexually transmitted diseases clinic. In comparison with Southern transfer hybridization, performed with the same probes used in the dot filter kit, the sensitivity, specificity, and positive and negative predictive values of dot filter hybridization were 90%, 94%, 74%, and 98%, respectively. Among patients with cervical cytologic dysplasia, HPV DNA was detected in 44% by dot filter hybridization and in 35% by Southern transfer hybridization. Although 26% of specimens positive by dot filter hybridization were not confirmed by Southern transfer hybridization, cervical dysplasia was detected in 5 (25%) of 20 with HPV DNA detected by dot filter hybridization alone, compared with 25 (8%) of those with no definitive evidence of HPV by either method (P = 0.009) and with 16 (30%) of 53 with HPV DNA detected by both methods (P = 0.7). The kappa statistic for interobserver and intraobserver reproducibility for interpretation of blots was similar for the two methods. The dot filter hybridization method evaluated appears to be a satisfactory alternative to Southern transfer hybridization for detection of HPV DNA.     

Detection and characterisation of human astroviruses in children with acute gastroenteritis in Blantyre,Malawi

In a 2-year hospital-based study of paediatric gastroenteritis in Blantyre, Malawi, astroviruses were detected by enzyme immunoassay in 15 (1.9%) of 786 inpatients and in 9 (2.3%) of 400 outpatients. Greater disease severity was noted in children coinfected with human immunodeficiency virus (HIV). Six human astrovirus (HAstV) genotypes were identified, including HAstV-1 (25%), HAstV-2 (21%), HAstV-3 (25%), HAstV-4 (13%), HAstV-5 (4%), and HAstV-8 (13%). Although astroviruses are not major causes of gastroenteritis among children admitted to hospital in Blantyre, concomitant HIV infection appears to be a risk factor for increased severity of disease.     

A live attenuated turkey rhinotracheitis virus vaccine. 1. Stability of the attenuated strain

Compared with the severe clinical disease caused by two virulent strains of turkey rhinotracheitis virus (TRTV), an attenuated strain has been shown to cause only slight respiratory infection in 7-day-old TRT-free turkey poults, yet still to be capable of stimulating TRT antibodies and of protecting the poults against challenge with virulent TRTV 21 days later. The stability of the attenuation during 12 turkey-turkey passages of the strain has been demonstrated; the poult passaged and prepassaged strains causing only mild respiratory signs even when bacteria, known to be associated with severe outbreaks of TRT in the field, were included in the inoculum.     

Effect of finite phosphor thickness on detective quantum efficiency

In this paper we describe theoretically the relationship between the finite thickness of a phosphor screen and its spatial-frequency-dependent detective quantum efficiency DQE(f-). The finite thickness of the screen causes a variation in both the total number of light quanta emitted from the screen in a burst from a given x-ray interaction and in the spatial distribution of the quanta within the light burst [i.e., shape or point spread function (PSF) of the light burst]. The variation in magnitude of the burst gives rise to a spatial-frequency-independent reduction in DQE, characterized by the scintillation efficiency As. The variation in PSF causes a roll off in DQE with increasing spatial frequency which we have characterized by the function Rc(f). Both As and Rc(f) can be determined from the moments of the distribution of the spatial Fourier spectrum of light bursts emitted from the phosphor and thus they are related: As is a scaling factor for Rc(f). Our theory predicts that it is necessary for all light bursts which appear at the output to have the same magnitude to maximize As and the same shape to maximize Rc(f). These requirements can lead to the result that the fluorescent screen with the highest modulation transfer function will not necessarily have the highest DQE(f) even at high spatial frequencies.     

Cell surface oligosaccharide modulation during differentiation: IV. Normal and transformed cell growth control

In previous studies it was shown that cell surface oligosaccharide affinity class distributions and binding capacities were down-regulated as normal cells approach senescence. Using a sensitive, amplified, lectin/specific-ligand competition analysis three other growth regulation states were compared to that of cellular senescence. Non-senescent and senescent low-density and contact-induced growth inhibition was compared with neoplastic cell growth control. Non-senescent human fetal lung fibroblasts (IMR-90) down-regulated their mannosyl and galactosyl specificities in response to both low-density and contact-induced growth inhibition. Senescent IMR-90 down-regulate their mannosyl residues in response to contact conditions while they up-regulate their galactosyl residues under the same conditions. Growth-transformed transplantable canine glioma cells did not show density-dependent regulation of their cell surface oligosaccharide structures. Modulation of the CG cells with a specific alpha-mannosidase II inhibitor, Ricinus communis a galactosyl specific lectin, and pokeweed mitogen a cellular differentiating agent resulted in an altered growth phenotype and up-regulation of the mannosyl and galactosyl surface oligosaccharides. These data indicate a controller function for the cell surface oligosaccharides and a general influence on growth control.     

Sema7A is a potent monocyte stimulator

Sema7A is a recently described member of the semaphorin family that is associated with the cell surface via a glycophosphatidylinositol linkage. This study examined the mRNA expression and biological properties of this protein. Although the expression of Sema7A was demonstrated in lymphoid and myeloid cells, no stimulation of cytokine production or proliferation was evident in B or T cells. In contrast, Sema7A is an extremely potent monocyte activator, stimulating chemotaxis at 0.1 pm and inflammatory cytokine production (interleukin-1 (IL-1beta), tumour necrosis factor-alpha (TNF-alpha), IL-6 and IL-8) and superoxide release at 1-10 pm. Sema7A is less effective at stimulating neutrophils. Sema7A also significantly increases granulocyte-macrophage colony-stimulating factor (GM-CSF) production from monocytes but has no consistent effect on IL-10, IL-12 or IL-18. Sema7A can also induce monocytes toward a dendritic cell morphology. Sema7A is expressed in monocytes and probably released through proteolysis and acts as a very potent autocrine activator of these cells.     

Magnitude of the inflammatory response to cardiopulmonary bypass and its relation to adverse clinical outcomes

INTRODUCTION: Cardiopulmonary bypass (CPB) induces an inflammatory response believed to contribute to postoperative morbidity. We hypothesized that the magnitude of the inflammatory response following CPB would be associated with adverse clinical outcomes. METHODS: Twenty-nine patients had plasma TNF, IL-6, IL-8, elastase, histamine, complement C5a, and complement C3a measured by ELISA before, during, and after cardiac operations employing CPB. Inflammatory mediator levels were analyzed with respect to outcomes. RESULTS: Mediator levels peaked at 4 h post-CPB and either returned to baseline or substantially decreased by 24 h. Patients with peak mediator levels above the median for the group as a whole were classified as 'hyper-responders'; those with levels below the median were classified as 'normal responders'. While IL-8, C3a, and IL-6 levels were independently associated with adverse outcomes, TNF, histamine, and C5a levels were not. Elastase levels trended towards adverse outcomes. IL-8 'hyper-responders' experienced significantly greater postoperative weight gain and had higher IL-8 levels at 24 h (p<0.05), with trends towards renal impairment and protracted supplemental oxygen requirements. C3a 'hyper-responders' strongly trended towards increased bleeding, delayed extubation, greater postoperative weight gain, and decreased levels of independent functioning at discharge (p < or = 0.10). IL-6 'hyper-responders' experienced significantly more postoperative bleeding, delayed extubation, and higher IL-6 levels at 24 h compared to 'normal responders' (p < 0.05). They strongly trended towards greater postoperative weight gain and decreased levels of independent functioning at discharge (p < or = 0.10). CONCLUSIONS: Patients who have an exaggerated inflammatory response to CPB tend to bleed more, require more respiratory support, demonstrate greater capillary leak via weight gain, and display a decline in independent functioning relative to normal responders. Thus, it appears that the magnitude of the inflammatory response to CPB adversely influences clinical outcomes.     

Characterisation of Haemophilus spp. isolated from infant conjunctivitis

Haemophilus strains isolated from children under the age of 11 months with conjunctivitis were characterised by biotype, sugar fermentation, plasmid pattern and outer-membrane-protein profiles. H. influenzae was the most common species identified and was separated into 14 groups based on sugar fermentation and biotype patterns and into more than 20 groups when plasmid and outer-membrane-protein profiles were included. Small (mol. wt less than 10 X 10(6)) plasmids were identified in 11 of 34 (32%) H. influenzae isolates, 1 of 2 H. haemolyticus and 4 of 6 (67%) H. parainfluenzae isolates. Examination of sugar-fermentation and plasmid patterns increased the ability to distinguish between strains isolated at different times from recurrent disease and may have general applications in the study of Haemophilus strains isolated from a single anatomical site.