Feline paediatric oncology: retrospective assessment of 233 tumours from cats up to one year (1993 to 2008)

Objectives : To determine which types of tumour occur in cats up to the age of 12 months based on biopsies submitted to Idexx Laboratories, Wetherby, UK. Methods : Retrospective review of histopathological diagnoses of tumours in cats up to the age of 12 months from biopsies received between September 1993 and March 2008. Results : A total of 4196 submissions from cats 12 months old or younger were identified; 233 biopsies (6%) were neoplastic and fulfilled the search criteria. Tumours were categorised as haematopoietic (n=73, 31%), malignant epithelial (n=44; 19%), malignant mesenchymal (n=38; 16%), benign epithelial (n=37; 16%), benign mesenchymal (n=30, 13%) and miscellaneous (n=11; 5%). The most frequent tumours were lymphoma (n=51; 22%), soft-tissue sarcoma (n=34; 15%), mast cell tumour (n=22; 9%) and squamous cell carcinoma (n=16; 7%). The most common tumour site was the skin and soft tissues (41% of tumours). In all, 164 neoplasms (70%) were malignant or had malignant potential. Clinical Significance : These data provide unique epidemiological information on a poorly characterised subgroup of feline cancer patients in the UK.     

Use of Cholesterol‐Loaded Cyclodextrin in Donkey Semen Cryopreservation Improves Sperm Viability but Results in Low Fertility in Mares

The use of cholesterol‐loaded cyclodextrin (CLC) on semen cryopreservation has been related with better sperm viability in several species; however, the effect on fertility is not known in donkey semen. Ejaculates (n = 25) from five donkeys were diluted in S‐MEDIUM with 0, 1, 2 or 3 mg of CLC/120 × 10⁶ spermatozoa. Semen was frozen, and thawed samples were evaluated by computer‐assisted sperm analyser system (CASA), supravital test, hyposmotic swelling test and fluorescent dyes to assess the integrity of sperm membranes. Mares (n = 60) were inseminated with frozen‐thawed semen treated with the doses of 0 or 1 mg CLC. Percentages of sperm with progressive motility and with functional plasma membrane were greater (p < 0.05) in the CLC‐treated groups than in the control. Percentages of intact plasma membrane and intact plasma membrane and acrosome detected by fluorescent dyes were also greater (p < 0.05) in CLC‐treated groups. Although no difference (p > 0.05) in conception rates was detected between groups (control, 3/30, 10%; CLC‐treated, 1/30, 3.3%), fertility was low for artificial insemination programs in mares. Therefore, we firstly demonstrated that frozen semen treated with CLC in S‐MEDIA extender before freezing improves the in vitro sperm viability, but semen treated or not with CLC in S‐MEDIUM extender results in a very low conception rate in mares inseminated with thawed donkey semen.     

Equatorial X-ray Emissions: Implications for Jupiter's High Exospheric Temperatures

Observations with the High Resolution Imager on the Rontgensatellit reveal x-ray emissions from Jupiter's equatorial latitudes. The observed emissions probably result from the precipitation of energetic (>300 kiloelectron volts per atomic mass unit) sulfur and oxygen ions out of Jupiter's inner radiation belt. Model calculations of the energy deposition by such heavy ion precipitation and of the resulting atmospheric heating rates indicate that this energy source can contribute to the high exospheric temperatures(>800 kelvin at 0.01 microbar) measured by the Galileo probe's Atmospheric Structure Instrument. Low-latitude energetic particle precipitation must therefore be considered, in addition to other proposed mechanisms such as gravity waves and soft electron precipitation, as an important source of heat for Jupiter's thermosphere.     

α-甘露聚糖肽对鲫鱼免疫应答强度的影响研究

为研究α-甘露聚糖肽(M annatide)对鲫鱼免疫应答强度的影响,将α-甘露聚糖肽按每天每千克体重1.5 m g的剂量拌饵投喂鲫鱼,分别于7,14,21和28 d时检测各组鲫鱼吞噬细胞的杀菌活性、白细胞的吞噬活性、SOD酶活性和血清凝集抗体效价。结果表明,不同投喂周期均可增强鲫鱼的免疫应答强度;用药饵投喂7 d的试验组,7 d后免疫应答强度很快与对照组趋于一致;21 d和28 d投喂组的免疫应答强度差异不明显,但均显著(P<0.05)高于14 d组。因此,投喂21 d左右即可达到使非特异性免疫功能增强持续30 d以上的效果。     

Risks due to groundwater contamination at a plutonium processing facility

The specter of contaminated groundwater looms over industrialized, suburban, and rural areas. The sources of groundwater contamination are many and the contaminants numerous. Historical waste disposal practices pose the greatest threat to groundwater in the United States. Common solvents such as trichloroethylene, tetrachloroethane, benzene, and carbon tetrachloride have been found in widespread areas. For this study, a risk assessment is performed using a multimedia environmental transport model to estimate public risk from a contaminated groundwater plume. From 1955 to 1973, a crib above the groundwater plume was used for the disposal of plutonium processing waste. The plume contains chemical and radioactive wastes that could pose a health threat to people living in the vicinity of the site. Remedial designs are selected for remediating the different contaminants in the groundwater plume through a multiple phase treatment process. This study evaluates: baseline health risks to the public, health risk reduction to the public as a result of the remedial activities, health risk to the workers directly involved in cleaning up the site, and costs associated with each remedial activity.     

Inter-specific hybrids of Lilium lankongense Franchet produced by embryo-culture

Summary Lilium lankongense crossed with some related species of Lilium produced seeds without endosperm and with very small embryos which would not germinate in soil. Hybrid plants have been obtained from a number of these crosses by culturing excised embryos on sterile nutrient medium. It is suggested that the technique may prove useful in the production of hybrids from other lily species-combinations which are not normally viable.     

Concentration of dietary calcium supplied by calcium carbonate does not affect the apparent total tract digestibility of calcium, but decreases digestibility of phosphorus by growing pigs

A regional experiment was conducted to test the hypothesis that the concentration of dietary Ca does not affect the digestibility of Ca or P in diets fed to growing pigs. Six diets based on corn, potato protein isolate, cornstarch, and soybean oil were formulated. All diets also contained monosodium phosphate, crystalline AA, salt, and a vitamin-micromineral premix. The only difference among the diets was that varying concentrations of calcium carbonate were used to create diets containing 0.33, 0.46, 0.51, 0.67, 0.92, and 1.04% Ca. All diets contained between 0.40 and 0.43% P. Six universities participated in the experiment and each university contributed 2 replicates to the experiment for a total of 12 replicates (initial BW: 23.1 ± 4.4 kg). Pigs were placed in metabolism cages that allowed total, but separate, collection of feces and urine from the pigs. Pigs within each replicate were randomly allotted to the 6 diets and fed experimental diets for 14 d with urine and feces being collected over a 5-d period. Diets, feces, and urine samples were analyzed for Ca and P, and the daily balance, the apparent total tract digestibility (ATTD), and the retention of Ca and P were calculated. Results indicated that intake, fecal excretion, and urinary excretion of Ca increased (linear, P<0.05) as dietary Ca concentration increased. The daily intake of P was not affected by the dietary concentration of Ca, but fecal excretion of P increased (linear, P<0.05) as dietary Ca concentrations increased. In contrast, urinary P output was decreased (linear, P<0.05) as dietary Ca increased. The retention of Ca increased (linear, P<0.05) from 1.73 to 4.60 g/d, whereas the retention of P decreased (linear, P<0.05) from 1.98 to 1.77 g/d as dietary Ca concentrations increased. However, if calculated as a percentage of intake, both Ca and P retention were decreased (linear, P<0.05) as dietary Ca concentration increased (from 55.4 to 46.1% and from 48.4 to 43.5%, respectively). The ATTD of Ca was not affected by the dietary concentration of Ca, but the ATTD of P was decreased (linear, P<0.05) from 56.9 to 46.2% as dietary Ca concentration increased. It is concluded that the dietary concentration of Ca does not affect the ATTD of Ca in calcium carbonate, but increased concentrations of dietary Ca may decrease the ATTD of P in diets based on corn, potato protein isolate, and monosodium phosphate.     

Expression of a cloned rat brain potassium channel in Xenopus oocytes

Potassium channels are ubiquitous membrane proteins with essential roles in nervous tissue, but little is known about the relation between their function and their molecular structure. A complementary DNA library was made from rat hippocampus, and a complementary DNA clone (RBK-1) was isolated. The predicted sequence of the 495-amino acid protein is homologous to potassium channel proteins encoded by the Shaker locus of Drosophila and differs by only three amino acids from the expected product of a mouse clone MBK-1. Messenger RNA transcribed from RBK-1 in vitro directed the expression of potassium channels when it was injected into Xenopus oocytes. The potassium current through the expressed channels resembles both the transient (or A) and the delayed rectifier currents reported in mammalian neurons and is sensitive to both 4-aminopyridine and tetraethylammonium.