Polyarteritis in a beagle

A 13-month-old Beagle became anorectic and had fever, stiff gait, and tenderness in the inguinal region. Clinical signs of disease were associated with neutrophilia and a decrease in the albumin-to-globulin ratio. The dog became clinically normal for 5 days after 3 days of treatment with penicillin G and dihydrostreptomycin. Clinical signs of disease recurred, and the dog was euthanatized after failing to respond to administration of a trimethoprim-sulfamethoxazole combination for 9 days. Disseminated arteritis was seen in the testes, epididymides, mesentery, coronary arteries, aorta, and thyroid gland. Lesions were seen in large and medium-sized arteries and varied from acute necrotizing arteries to a chronic lesion with organization and recanalization of thrombi. The clinical signs of disease resembled those of Beagle pain syndrome, described in laboratory Beagles.     

Breast cancer prevention by green tea catechins and black tea theaflavins in the C3(1) SV40 T,t antigen transgenic mouse model is accompanied by increased apoptosis and a decrease in oxidative DNA adducts

Tea consumption is associated with a reduced risk of mammary cancer as reflected by epidemiological studies and experiments in carcinogen-induced rodent models of mammary carcinogenesis. We tested the hypothesis that green tea catechins (GTC) or theaflavins from black tea (BTT) interfere with mammary carcinogenesis in C3(1) SV40 T,t antigen transgenic multiple mammary adenocarcinoma (TAg) mice and that GTC/BTT affect tumor survival or oxidation status. TAg mice received GTC/BTT (0.05%) in drinking water for their lifetime. As compared to control mice, they survived longer and had smaller tumors. On microscopic inspection, the size of the largest tumor per mouse was decreased by 40-42% (p<0.01). GTC (0.01%) and BTT (0.05%) increased levels of cleaved caspase 3 in tumor tissue by 67 and 38%, respectively (p<0.05), intimating increased apoptosis. Tumor levels of the malondialdehyde-DNA adduct M1dG in mice receiving GTC or BTT (0.05%) were reduced by 78 (p<0.001) or 63% (p<0.05), respectively, as compared to controls. The results render the exploration of the breast cancer chemopreventive properties of tea preparations in humans worthwhile.     

Identifying vibrations that destabilize crystals and characterize the glassy state

High-resolution inelastic neutron scattering was used to identify major sources of low-frequency vibrations in zeolite crystals. Dispersed and nondispersed modes were found, both of which are prominent in the early stages of compressive amorphization but decline dramatically in strength once a glass of conventional density is created. By identifying the dispersed modes with the characteristic vibrations of the various secondary building units of zeolitic structures, the Boson peak, a characteristic of the glassy state, can be attributed to vibrations within connected rings of many different sizes. The nondispersed phonon features in zeolites, retained in the amorphized glass, were also replicated in silica. These modes are librational in origin and are responsible for destabilizing the microporous crystalline structure, for converting the resulting glass from a low- to a high-density phase, and for the associated changes in network topology that affect the Boson peak.     

Initiating and cancer-propagating cells in TEL-AML1-associated childhood leukemia

Understanding cancer pathogenesis requires knowledge of not only the specific contributory genetic mutations but also the cellular framework in which they arise and function. Here we explore the clonal evolution of a form of childhood precursor-B cell acute lymphoblastic leukemia that is characterized by a chromosomal translocation generating a TEL-AML1 fusion gene. We identify a cell compartment in leukemic children that can propagate leukemia when transplanted in mice. By studying a monochorionic twin pair, one preleukemic and one with frank leukemia, we establish the lineal relationship between these "cancer-propagating" cells and the preleukemic cell in which the TEL-AML1 fusion first arises or has functional impact. Analysis of TEL-AML1-transduced cord blood cells suggests that TEL-AML1 functions as a first-hit mutation by endowing this preleukemic cell with altered self-renewal and survival properties.     

Book reviews

Rodents in Agriculture: A Review of Findings in Bangladesh. By H. Posamentier: Sonderpublikation der GTZ No. 176, 1989, 107 pp. ISBN 3–88085–306–1. Price DM 22.00 (approx. £7.50 or US$13.00).

Motivating Farmers for Action: how strategic multimedia campaigns can help; results and experiences of the Bangladesh rat control campaign. By R. Adhikarya and H. Posamentier. Eshborn: Deutsche Gesellschaft fur Technische Zusammenarbeit (GTZ), 1987, pp. 209. ISBN 3–88085–289–8.     

Patterns of longitudinal within-tree variation in pulpwood and solidwood traits differ among Eucalyptus globulus genotypes

Wood discs were sampled from 6 heights up the stem of 248 trees representing 10 subraces and 116 families grown in an E. globulus base-population progeny trial. The lower stem had the least favourable wood properties for kraft pulpwood and most solidwood applications: bark was thickest, basic density was lowest and kino, decay and shrinkage traits were greatest at or below 12% of tree height. Significant genetic differences at the subrace level were revealed in diameter, bark thickness, basic density, decay and gross shrinkage and at the family within subrace level in diameter, basic density and decay. However, subrace-by-height-category interactions in bark thickness, basic density, decay and gross shrinkage indicated that differences among subraces were dependent on height in these traits. Examination of longitudinal trends revealed some evidence that the zone of thick basal bark extended further up the stem in thicker-barked subraces and that the Southern Tasmania subrace might be less effective than other subraces in restricting the longitudinal spread of decay after infection.     

Sunglint patterns: unusual dark patches

Anomalous dark areas in sunglint patterns are occasionally seen in photographs taken by the Applications Technology Sattellte. These dark areas appear to be caused by relatively calm surface conditions against a background of higher sea states. Evidence of cold water temperatures suggest the presence of upwelling. These sightings may thus be of importance to the fishing industry.     

Micromorphology of the bacterial attack of wood

Summary This paper describes fully the various patterns of bacterial attack to be observed in wood. It is based on many observations made with bacterially infected wood, both in pure laboratory cultures and in naturally attacked wood from diverse environments. Patterns of attack are described for tracheids, fibres, vessles and rays and three types of pit border decay are figured, together with attack of the pit margo and torus. A brief section also deals with the macroscopic appearances of wood subject to bacterial attack.

---

Zusammenfassung Auf Grund zahlreicher Versuche und Beobachtungen werden die verschiedenen Formen bakteriellen Befalles von Holz, sowohl bei inokulierten Laborkulturen als auch bei natürlich infizierten Hölzern von verschiedenen Waldstandorten, eingehend beschrieben.Im einzelnen umfassen die geschilderten Befallsformen diejenigen, von denen Tracheiden, Fasern, Gefäße und markstrahlen betroffen werden; außerdem werden drei Typen von Tüpfelwulstfäule, sowie je ein Fall von Bakterienbefall eines Tüpfelhofes und einer Tüpfelschließhaut dargestellt.Dem makroskopischen Aussehen bakterienbefallener Hölzer wird ein kurzer Abschnitt gewidmet.