Nasopharyngeal nephroblastoma in a 3-month-old Boer goat

A 3-mo-old, female Boer goat was presented because of respiratory difficulties. Tachypnea and inspiratory dyspnea were noted during physical examination. Thoracic radiographs were unremarkable; however, upper airway and nasal passage radiographs revealed a soft tissue mass within the nasal passages. The patient underwent cardiorespiratory arrest and did not respond to resuscitation efforts during endoscopy. A large, pedunculated, semi-firm mass originated from the soft palate and obstructed 90% of the nasopharynx on autopsy. Histologically, the mass was composed of primitive cells that multifocally formed tubules and glomeruloid structures intermingled with areas of fusiform and blastemal cells. The neoplastic cells were positive for cytokeratin (tubular and glomeruloid cells), vimentin (fusiform population and blastemal cells), and Wilms tumor 1 protein (glomeruloid structures) on immunohistochemistry, consistent with a triphasic nephroblastoma. To our knowledge, nasopharyngeal nephroblastoma has not been reported previously in any species.     

Heavy metal and sulphur concentrations in Sphagnum magellanicum brid. In the Maritime Provinces,Canada

Water, Air, & Soil Pollution - A regional survey of selected heavy metals and S concentrations in Sphagnum magellanicum Brid. was completed within the Maritime Provinces, Canada. The...     

Methylmercury in runoff from the Svartberget Catchment in northern Sweden during a stormflow episode

The dynamics of MeHg during rain-driven runoff episodes are important in calculating the output of MeHg from forested catchments. These dynamics may also provide insight into the processes controlling MeHg output from soils to surface waters. The concentrations of MeHg, Hg-tot, TOC and associated chemistry were observed during a rain-driven, July runoff episode on two forested tributaries of the Svartberget Catchment, as well as at the outlet of a mire in the headwaters of that catchment. TOC concentrations in runoff increased during the episode. Hg-tot concentrations also tended to increase (from 3 to between 4 and 7 ng L^?1), though the timing of that increase varied. MeHg concentrations, on the other hand, tended to decrease. The decrease was slight in the two forested tributaries (ca. 0.1 ng L^?1), but greater in the mire runoff (from 0.8 to ca 0.3 ng L^?1). These data are set in relation to a hypothesis about the processes which control MeHg output.     

Culture of commercially obtained Lumbricus terrestris L.: Implications for sub-lethal ecotoxicological testing

The use of commercially purchased or field-collected earthworms of unknown age, exposure or pre-treatment in sub-lethal ecotoxicological studies is questionable. In this study, adult (clitellate) Lumbricus terrestris, obtained from 5 commercial suppliers in the UK and also field collected, were kept under controlled environmental conditions (15 °C and 24 h darkness) in a sterilised loam soil and fed horse manure. Survival, biomass and cocoon production was monitored every 4 weeks over 1 y. Marked differences were recorded in survival rates (ranging from 40-100% after 40 weeks) and cocoon production (ranging from 15.1 to 32.2 worm⁻¹ y⁻¹) between treatments. Biomass in all treatments (mean mass 4.32-5.61 g at the outset) increased with time to week 20 (maximum 6.7 g) and then declined steadily (3.23-4.7 g at week 52). This pattern was also observed in cocoon production and was considered to be a function of an initial period of acclimation (0-12 weeks) followed by a period of high production (12-36 weeks) under optimal conditions and then fatigue (36-52 weeks) caused by reproductive exhaustion. Results suggest that earthworm origin may influence the validity and reproducibility of sub-lethal ecotoxicological studies and where applicable laboratory-reared earthworms of known age and history are recommended as test subjects.     

Potential terrain controls on soil color, texture contrast and grain-size deposition for the original catena landscape in Uganda

Inspired by the catena concept, we returned to the landscape of origin for this idea in central Uganda and applied quantitative soil-landscape-modeling techniques to the study of soil formation. In particular, we employed Generalized Least Squares (GLS) regression to identify potential terrain (and other) controls on surface texture with the goal of explaining texture contrast formation for well-drained red soils, and fluvial deposition for yellow-gray lowland soils. Well-drained red soils and poorly drained yellow-gray soils were identified using a high-resolution spectroradiometer and soil redness was highly correlated with a measure of elevation above the valley floor. For the yellow-gray soils, sand content and sand grain size increased with greater slope gradient and in converging areas—evidence supporting fluvial control of surface soil composition. For red soils, texture contrast increased on lower backslopes, decreased over ferricrete-rich parent material, and had no significant association with either infiltration- or runoff-influenced locations. Surprisingly, texture contrast was also reduced or even inverted on fine scale convexities (<18 m in diameter). These findings were consistent with the following theoretical processes: (1) sand deposition on lower-backslopes, increasing texture contrast; (2) ferricrete weathering at the soil surface, reducing texture contrast; and (3) texture contrast inversion through termite turbation. A number of techniques proved useful in this study: (a) the use of GLS regression supported the interpretation of model coefficients in an explicitly spatial context; (b) thin-plate splines provided a flexible means of controlling the spatial scale of terrain index computation; and (c) the development of a new downslope-looking Elevation Above Stream (EASy) terrain index provided a powerful tool for the identification of poorly drained soils—a tool that could have applications in a variety of landscapes and environments. Overall, we found that the catena concept as a soil-terrain-modeling approach worked best on lower, less well-drained, depositional landscape components. For the well-drained portion of this landscape, there was little evidence to suggest that soil formation was controlled by hillslope hydrology as proposed by the catena concept. The catena concept interpreted in a broad sense challenges pedologists to explicitly link soil geographic patterns with specific soil forming processes and environmental controls—an approach that proved valuable in this study.     

Regional-scale drought increases potential soil fertility in semiarid grasslands

Although drying of soil has increased fertility in laboratory-based experiments, a direct link between longer-scale weather conditions associated with drought and soil fertility has not been documented at the field scale. Soil from a semiarid grassland on the Sevilleta National Wildlife Refuge (NWR) that was collected over a 10-year period had the highest levels of potentially mineralizable nitrogen (PMN, a measure of potential soil fertility) during drought periods in 1989 and 1995. Whereas previous soil collections on the Sevilleta NWR were made for different reasons, soils were collected in June 2002 near the peak of a regional-scale drought to test the hypothesis that potential soil fertility increased with drought. Another semiarid grassland site, the Bernalillo Watershed, was sampled to extend the spatial extent of the analysis. The 2002 collections showed soil PMN near the highest at both sites, thereby supporting the hypothesis. Longer-term PMN data at both sites were correlated with the Palmer Drought Index (PDI), a regional-scale index with drier periods given negative values. Over a 13-year period, the Sevilleta soils had higher PMN during periods of drought (r =–0.533, P <0.05). Although not significant, a similar trend was shown over an 8-year record at the Bernalillo Watershed (r =–0.356, not significant). Also, PMN levels measured during a previous 3-year wet-to-drought period at another semiarid grassland site on the Sevilleta NWR were highly significantly correlated with the PDI (r =–0.723, P <0.01). Thus, drought can increase soil fertility, which can alter additional ecosystem processes.     

Triacylglycerol structure and composition of hydrogenated soybean oil margarine and shortening basestocks

The composition and structures of triacylglycerols (TAG) in a commercially prepared hydrogenated soybean oil margarine basestock [iodine value (IV) 65, 39.7% trans fatty acids] were determined by high-performance liquid chromatography (HPLC) in tandem with atmospheric pressure chemical ionization (APCI) mass spectrometry (MS). The basestock was separated by preparative HPLC into four fractions. Fractions 1 and 4, constituting approximately 8% of the total, were shown to consist of LOO, PLO, and LLS and OSS and PSS, respectively (where L = linoleic, O = oleic, S = stearic, and P = palmitic). APCI will not distinguish between O, oleic cis C18:1, and E, elaidic trans C18:1. Thus, O and E may be used interchangeably in discussion of TAG isomer structures. Fraction 2 consisted of OOO and POO. Fraction 3 consisted of OOO, POO, OOS, and POS. About 80% of the total triglycerides consisted of OOO, POO, and OOS. The trans fatty acid content of the fractions was determined, and the results showed that 92% of the total trans content was found in fractions 2 and 3. A shortening basestock (IV 81.7, 31.8% trans fatty acids) was partially characterized.