Widely dispersed p53 mutation in respiratory epithelium. A novel mechanism for field carcinogenesis

Individuals with one aerodigestive tract malignancy have a high incidence of second primary aerodigestive tumors. The mechanism for this field effect has not been determined. We studied an individual with widespread dysplastic changes in the respiratory epithelium but no overt carcinoma. The entire tracheobronchial tree obtained at autopsy was embedded in paraffin, and bronchial epithelial cells were isolated by microdissection. DNA extracted from the microdissected cells was analyzed for point mutations in the p53 tumor suppressor gene. A single, identical point mutation consisting of a G:C to T:A transversion in codon 245 was identified in bronchial epithelium from 7 of 10 sites in both lungs. Epithelium at sites containing the p53 mutation was morphologically abnormal, exhibiting squamous metaplasia and mild to moderate atypia. No invasive tumor was found in the tracheobronchial tree or any other location. Cells from peripheral blood, kidney, liver, and lymph node exhibited no abnormality in the p53 gene. The widespread presence of a single somatic p53 point mutation in the bronchi of a smoker suggests that a single progenitor bronchial epithelial clone may expand to populate broad areas of the bronchial mucosa-a novel mechanism for field carcinogenesis in the respiratory epithelium that may be of importance in assessing individuals for risk of a second primary tumor as well as in devising effective strategies for chemoprevention of lung cancer.     

Controlled Distribution of Solid Catalysts into Two Immiscible Liquid Phases – Synthesis and Catalytic Applications

Photometathesis of C₃H₆ proceeded on the sprayed MoO₃ catalyst under UV irradiation with wavelength <290 nm. The photoactivity on the spray catalyst was 20-fold higher than that on the commercial MoO₃. The X-ray diffraction (XRD) results showed the anisotropic growth of the crystal in the spray catalyst. The edge-rich structure was formed in the bulk molybdenum oxide by spray reaction technique.     

Effects of altering testosterone in early infancy on social behaviour in captive yearling rhesus monkeys

Thirteen male and twenty female rhesus monkeys (Macaca mulatta), aged 9-12 months, living as members of long term captive social groups, were observed in order to quantify sex differences in a variety of behaviour patterns. Six males had been treated with a GnRH agonist (Meterelin: M) during their first six postnatal months, in order to block the surge of testosterone which occurs at this time. Ten females had been treated with testosterone (T) during their first six months, in order to mimic the postnatal T surge seen in males. The remaining 7 males and 10 females acted as control subjects. Marked sex differences were measured in frequencies of play and socio-sexual behaviour in these juvenile monkeys. However, neither M nor T treatments produced any significant changes in frequencies of these behaviour patterns. Although M-treated males showed a tendency (p < 0.1) to groom others for longer periods than control males, and control females tended to spend more time alone than T-treated females, we were unable to measure any significant (p < 0.05) effects of either M- or T-treatment upon affiliative behaviour in juvenile rhesus monkeys. We conclude, therefore, that the postnatal T surge in male rhesus monkeys does not affect development of sexually dimorphic and associated patterns of behaviour. Presumably, organisational effects of T upon these behaviour patterns must be completed before birth in this species.     

A carcinoembryonic antigen polynucleotide vaccine for human clinical use

Congenital cataract, type Volkmann (McKusick no 115665, gene symbol CCV) is an autosomal dominant eye disease. The disease is characterized by a progressive, central and zonular cataract, with opacities both in the embryonic, fetal and juvenile nucleus and around the anterior and posterior Y-suture. We examined blood samples from 91 members of a Danish pedigree comprising 426 members, by using highly informative short tandem repeat polymorphisms and found the closest linkage of the disease gene (CCV) to a (CA)n dinucleotide repeat polymorphism at locus D1S243 (Zmax = 14.04 at theta M = 0.025 theta F = 0.000), at a penetrance of 0.90. Using two additional chromosome 1 markers, we were able to map the CCV gene in the sequence 1pter-(CCV, D1S243)-D1S468-D1S214. The (enolase 1) gene has been mapped to this area; however, a mutation described in this gene did not give eye disease.     

Overview of the Mars Pathfinder mission and assessment of landing site predictions

Chemical analyses returned by Mars Pathfinder indicate that some rocks may be high in silica, implying differentiated parent materials. Rounded pebbles and cobbles and a possible conglomerate suggest fluvial processes that imply liquid water in equilibrium with the atmosphere and thus a warmer and wetter past. The moment of inertia indicates a central metallic core of 1300 to 2000 kilometers in radius. Composite airborne dust particles appear magnetized by freeze-dried maghemite stain or cement that may have been leached from crustal materials by an active hydrologic cycle. Remote-sensing data at a scale of generally greater than approximately 1 kilometer and an Earth analog correctly predicted a rocky plain safe for landing and roving with a variety of rocks deposited by catastrophic floods that are relatively dust-free.     

Hydrogen-bonded diketopyrrolopyrrole (DPP) pigments as organic semiconductors

Diketopyrrolopyrroles (DPPs) have recently gained attention as building-blocks for organic semiconducting polymers and small molecules, however the semiconducting properties of their hydrogen-bonded (H-bonded) pigment forms have not been explored. Herein we report on the performance of three archetypical H-bonded DPP pigments, which show ambipolar carrier mobilities in the range 0.01–0.06 cm²/V s in organic field-effect transistors. Their semiconducting properties are correlated with crystal structure, where an H-bonded crystal lattice supports close and relatively cofacial π–π stacking. To better understand transport in these systems, density functional theory calculations were carried out, indicating theoretical maximum ambipolar mobility values of ∼0.3 cm²/V s. Based on these experimental and theoretical results, H-bonded DPPs represent a viable alternative to more established DPP-containing polymers and small molecules where H-bonding is blocked by N-alkylation.