Time of appearance and histology of tumors induced in the dorsal skin of C3Hf mice by ultraviolet radiation from a mercury arc lamp

The time course of skin tumor induction was determined in hair-clipped inbred agouti C3Hf mice irradiated three times per week with a medium-pressure quartz-mercury lamp; 4 different UV doses were used. Although the ears were also exposed to the radiation, in the 3 groups given the highest doses no ear tumors were observed by the time each animal had developed at least 1 tumor on its back. No tumors were found in the animals receiving the lowest UV dose. In the group receiving the highest dose, males developed tumors earlier than did females; this trend continued in the lower dose groups. Many tumors that developed in the back skin were well-differentiated squamous cell carcinomas. Others were less well-differentiated squamous cell carcinomas. Others were less well defined so that the cell of origin was difficult to determine. In the group receiving the highest UV dose, the squamous cell carcinomas were few, whereas at the lower doses they predominated.     

Pi (antitrypsin) typing methods. A comparison of acid starch-gel electrophoresis and isoelectric focusing

The Pi typing methods acid starch-gel electrophoresis (ASGE) and isoelectric focusing (IEF) have been compared by three reference laboratories: 564 samples of phenotypes Pi M, MS and MZ were tested in each of the three laboratories with a 96% agreement on initial typing. The discrepancies are recorded and reasons for disagreement discussed. IEF is a reliable method for Pi typing and gives results comparable to those obtained by ASGE.     

Note on the movement of insecticide droplets through and out of a crop canopy after emission below canopy level

Coarse aerosol sprays with number median diameters in the range 30–40 μm were emitted at 0.25 m above the ground within the canopy of a cotton crop planted at 0.93 m row separation and standing 1.0 m tall. Movement of spray was monitored by vertical stepped paper tower samplers with narrowest section of width 0.13 cm, giving collection by inertial impaction down to 10 μm in a 1 m/sec wind. Horizontal paper targets were used to sample droplets depositing by sedimentation. Droplet number counts indicated that under conditions of moderate instability and associated convective turbulence, droplets were drawn rapidly out of the crop to a height of 2 m (the upper level sampled). The peak concentration of the spray cloud was centred at a height of between 1.0 and 2.0 m beyond 1.0 m downwind of the emission point in the first test, using droplet spectrum with volume median diameter of 41 μm, and beyond 2.5 m downwind of the emission point in the second test with spectrum of 57 μm volume median diameter. Inertial impaction at the 0.25 and 0.5 m levels was slight, except on the samplers within 0.5 m of the sprayer, and sedimentation was only significant at and below 0.5 m in the first two rows sampled. The moderate wind speed of 2.5 m/sec at canopy level produced marked inertial impaction over the first 4.5 m downwind of the sprayer at the 1.0 m level.     

Mutation in the Arabidopsis PASTICCINO1 gene, which encodes a new FK506-binding protein-like protein, has a dramatic effect on plant development

The pasticcino (pas) mutants of Arabidopsis thaliana are a new class of plant developmental mutants; members of this class show ectopic cell proliferation in cotyledons, extra layers of cells in the hypocotyl, and an abnormal apical meristem. This phenotype is correlated with both cell division and cell elongation defects. There are three complementation groups of pas mutants (pas1, pas2, and pas3, with, respectively 2, 1, and 4 alleles). Here we describe in more detail the pas1-1 allele, which was obtained by insertional mutagenesis. The PAS1 gene has been cloned and characterized; it encodes an immunophilin-like protein similar to the p59 FK506-binding protein (FKBP52). PAS1 is characterized by an FKBP-like domain and three tetratricopeptide repeat units. Although the presence of immunophilins in plants has already been demonstrated, the pas1-1 mutant represents the first inactivation of an FKBP-like gene in plants. PAS1 expression is altered in pas1 mutants and in the pas2 and pas3 mutants. The expression of the PAS1 gene is increased in the presence of cytokinins, a class of phytohormones originally discovered because of their ability to stimulate cell division. These results are of particular relevance as they show for the first time that an FKBP-like protein plays an important role in the control of plant development.     

Results of cemented metal-backed acetabular components: a 10-year-average follow-up study

We have developed a computer program for the rapid assessment of the primary structure differences between a protein of unknown sequence and a homologous known protein. Both proteins are reduced, alkylated, and digested with the same hydrolytic agent. The unfractionated peptide mixtures are submitted to automatic sequence analysis. Based on the knowledge of the reference sequence, the program utilizes the analysis data to identify all the potential peptides present in the two mixtures, determining their primary structure, homology degree, and molecular weight calculated both as integer MH+ and average mass variables. These fingerprints allow the user to easily identify the structural differences between the two proteins and clarify possible doubts by a mass spectrometric analysis of the two mixtures. In order to verify the utility of the program, we provide an application example using the already reported data of two homologous proteins.     

Toxicity of nitro compounds fromLotus pedunculatus to grass grub (Costelytra zealandica) (Coleoptera: Scarabaeidae)

Crude extracts of root of the forage legumesLotus pedunculatus andCoronilla varia (crownvetch) were toxic when administered orally to 3rd instarCostelytra zealandica larvae. A group of 3-nitropropanoyl-d-glucopyranoses was isolated from active fractions of the crude extracts. These toxins, some of which were already known fromC. varia, have not previously been reported fromL. pedunculatus. The compounds were present in root tissue of this species at a concentration of about 1% dry weight. They include the triester karakin and the diesters coronarian and cibarian, all of which were toxic to larvae ofC. zealandica at levels which could account fully for the activity of the crude extracts.     

Esterified estrogens with and without methyltestosterone decrease arterial LDL metabolism in cynomolgus monkeys

OBJECTIVES: To assess retinal complications and to identify risk factors for retinal complications following aqueous shunt procedures. MATERIALS AND METHODS: Records of 38 consecutive aqueous shunt procedures that were performed on 36 patients at the Eye Institute of the Medical College of Wisconsin, Milwaukee, from June 1993 to March 1995 (minimum follow-up, 6 months) were reviewed. The mean +/- SD follow-up was 11.4 +/- 5.2 months (median, 10.5 months). RESULTS: Twelve patients (32%) had the following retinal complications: 4 serous choroidal effusions (10%) that required drainage, 3 suprachoroidal hemorrhages (8%), 2 vitreous hemorrhages (5%), 1 rhegmatogenous retinal detachment (3%), 1 endophthalmitis (3%), and 1 scleral buckling extrusion (3%). Surgical procedures for retinal complications were required in 8 (67%) of these 12 patients. Visual acuity decreased 2 lines or more in 9 (75%) of these 12 patients. The median onset of a postoperative retinal complication was 12.5 days, with 10 patients (83%) experiencing complications within 35 days. Serous choroidal effusions developed in 10 other patients (26%), and these effusions resolved spontaneously. Visual acuity decreased 2 lines or more in 2 (20%) of these additional 10 patients. Patients who experienced serious retinal complications were significantly older, had a higher rate of hypertension, and postoperative ocular hypotony. Serious retinal complications were distributed evenly among patients with Krupin valves with discs and Molteno and Baerveldt devices. Experience with the Ahmed glaucoma valve implant was limited. CONCLUSION: Aqueous shunt procedures may be associated with significant retinal complications and subsequent visual loss.