Expression of p53, pRB,and p16 in lung tumours: a validation study on tissue microarrays

Tissue microarrays have been created from 326 lung tumours, including 173 squamous cell carcinomas (SCCs) and 132 adenocarcinomas (ADs). In order to evaluate the usefulness of this microarray series, the expression of p53, p16, and Rb proteins was compared by immunohistochemistry on both the tissue microarrays and the corresponding whole sections for all 326 tumours. The presence of replicate punches improved both the yield and the concordance of data relative to the whole section results, so that the consensus score from the replicates agreed with the whole section result in more than 90% of informative tumours. The large number of tumours in this series also allowed significant differences in protein expression patterns to be detected between SCC and AD, the major subtypes of non-small cell lung carcinoma (NSCLC). SCC had higher levels of p53 staining (67% vs 52% in AD) and substantially increased p16 loss (SCC 75%, AD 53%) combined with greater retention of pRB expression (SCC 86% vs 67% in AD). The strong inverse correlation between p16 and pRB seen in SCC was essentially absent in AD. This study represents the largest single immunohistochemical survey of protein expression for p53, p16, and RB in NSCLCs.     

Physical properties of hydrated tissue determined by surface interferometry of laser-induced thermoelastic deformation

Knee meniscus is a hydrated tissue; it is a fibrocartilage of the knee joint composed primarily of water. We present results of interferometric surface monitoring by which we measure physical properties of human knee meniscal cartilage. The physical response of biological tissue to a short laser pulse is primarily thermomechanical. When the pulse is shorter than characteristic times (thermal diffusion time and acoustic relaxation time) stresses build and propagate as acoustic waves in the tissue. The tissue responds to the laser-induced stress by thermoelastic expansion. Solving the thermoelastic wave equation numerically predicts the correct laser-induced expansion. By comparing theory with experimental data, we can obtain the longitudinal speed of sound, the effective optical penetration depth and the Grüneisen coefficient. This study yields information about the laser tissue interaction and determines properties of the meniscus samples that could be used as diagnostic parameters.     

Hand involvement in Schmid metaphyseal chondrodysplasia

Schmid metaphyseal chondrodysplasia (Schmid MCD, MIM 156500) is caused by mutations in the COL10A1 gene and is clinically characterized by short stature, bowed legs, and a waddling gait. Radiographic findings include anterior cupping, sclerosis and splaying of the ribs, diffuse metaphyseal flaring, and irregularity that is most pronounced at the knees, coxa vara, and femoral bowing. We reviewed the radiographs of Schmid MCD patients at the International Skeletal Dysplasia Registry in Los Angeles for evidence of hand involvement. We found hand involvement in 47% (7/15) of cases included in our analysis. These changes were subtle and consisted of shortening of the tubular bones and metaphyseal cupping of the proximal phalanges and metacarpals. Mild hand involvement is a common feature of Schmid MCD.     

A dinucleotide mutation in the endothelin-B receptor gene is associated with lethal white foal syndrome (LWFS); a horse variant of Hirschsprung disease

Lethal white foal syndrome (LWFS) is a congenital anomaly of horses characterized by a white coat colour and aganglionosis of the bowel, which is similar to Hirschsprung disease (HSCR). We decided to investigate possible mutations of the endothelin-B receptor gene ( EDNRB ) in LWFS as recent studies in mutant rodents and some patients have demonstrated EDNRB defects. First, we identified a full-length cDNA for horse EDNRB . This cDNA fragment contained a 1329 bp open reading frame which encoded 443 amino acid residues. The predicted amino acid sequence was 89, 91 and 85% identical to human, bovine and mouse as well as rat EDNRB respectively, but only 55% identical to the human, bovine and rat endothelin A receptor (EDNRA). Secondly, sequence analysis, together with allele-specific PCR and the amplification- created restriction site (ACRS) technique, revealed a dinucleotide TC-- >AG mutation, which changed isoleucine to lysine in the predicted first transmembrane domain of the EDNRB protein. This was associated with LWFS when homozygous and with the overo phenotype when heterozygous.      

Virulence of Campylobacter jejuni for chicken embryos is associated with decreased bloodstream clearance and resistance to phagocytosis.

The 11-day-old chicken embryo has been shown to be a useful animal model for comparing the virulence of human isolates of Campylobacter jejuni. Virulence in this system is associated with the ability to invade the chorioallantoic membrane and to survive and proliferate in vivo. In this study, the survival and multiplication of C. jejuni in the embryonic host was investigated. It was possible to enhance the virulence of a relatively avirulent C. jejuni strain by passaging it intravenously through the embryos. The resulting isogenic variants demonstrated enhanced abilities to survive in vivo but were still unable to invade when inoculated onto the chorioallantoic membrane. The bloodstream clearance of C. jejuni was studied, and virulent, but not avirulent, strains persisted and multiplied both in the bloodstream and in embryonic liver. Virulent strains also were cleared significantly more slowly from the bloodstream of adult BALB/c mice after intravenous challenge than were avirulent strains. C. jejuni strains which were cleared slowly in vivo were also ingested slowly in vitro by mouse peritoneal macrophages. Clearance studies in mice pretreated with cobra venom factor demonstrated that opsonization by serum complement was not a prerequisite for clearance of campylobacters from the murine bloodstream.     

Detection of Borrelia burgdorferi in human blood and urine using the polymerase chain reaction.

We investigated the use of the polymerase chain reaction (PCR) to detect Borrelia burgdorferi strain B-31 in human blood and urine experimentally inoculated with 5 and 1 borreliae/cm3, respectively, and to biotinylate a DNA probe specific for B. burgdorferi in the dot blot and Southern blot assays. When the blood and urine samples were subjected to PCR, a 370-bp amplified product was consistently visible on agarose gel electrophoresis after 30 and 45 cycles, respectively. The total human genomic DNA extracted from a 1-cm3 sample of inoculated blood was approximately 6.25 micrograms, and the total amount of B. burgdorferi DNA was estimated to be 0.01 pg/6.25 micrograms of the human DNA. For PCR, 2.5 micrograms of human DNA which contained the equivalent of 0.004 pg of borrelia DNA (approximately two borreliae) were used for enzymatic amplification. When 1/20 or 1/10 of the PCR-amplified products were used either for dot blot or Southern blot hybridization, the accessible copies of amplified B. burgdorferi DNA were sufficient for detectable hybridization to occur. PCR amplification of B. burgdorferi DNA in clinical specimens followed by dot blot hybridization may be a valuable adjunct or alternative to current but inadequate laboratory methods for the diagnosis of Lyme disease.     

Detection of parvovirus B19 DNA, antigen, and particles in the human fetus

Human parvovirus B19 commonly infects children, causing erythema infectiosum (fifth disease). However, there is a significant adult population which has not been exposed to the virus and, consequently, does not have protective antibody. Recent reports have associated B19 infection during pregnancy with fetal death, although normal outcome of pregnancy is more common. To characterise further the role of B19 infection in fetal deaths, a series of laboratory investigations has been undertaken on tissues obtained at autopsy. These have demonstrated the presence of virion-sized DNA by Southern blotting, viral antigen by radioimmunoassay, and viral particles by electron microscopy, all from tissues of hydrops fetalis. These data confirm that the human parvovirus B19 can cross the placenta and replicate in fetal tissues.