Differential Rotation and Dynamics of the Solar Interior

Splitting of the sun's global oscillation frequencies by large-scale flows can be used to investigate how rotation varies with radius and latitude within the solar interior. The nearly uninterrupted observations by the Global Oscillation Network Group (GONG) yield oscillation power spectra with high duty cycles and high signal-to-noise ratios. Frequency splittings derived from GONG observations confirm that the variation of rotation rate with latitude seen at the surface carries through much of the convection zone, at the base of which is an adjustment layer leading to latitudinally independent rotation at greater depths. A distinctive shear layer just below the surface is discernible at low to mid-latitudes.     

Wounds of the pastern and foot region managed with phalangeal casts: 50 cases in 49 horses (1995–2006)

Objective   Describe the use of a phalangeal cast as treatment for wounds in the pastern and foot region of horses. Secondly, to evaluate the healing and soundness of horses treated with phalangeal casts.
Design   Retrospective study of 49 horses.
Procedures   Medical records of 49 horses that were treated with a phalangeal cast for 50 cases of wounds in the pastern and foot region at equine referral hospitals from 1995 to 2006 were reviewed and follow-up information was obtained.
Results   Treatment consisted of wound debridement, lavage, wound closure (28 wounds), cast application and antibiotics (84%). At follow-up, the majority of horses were sound (42 of 47 wounds, 89.4%), three horses were still lame and one horse was euthanased because of persistent lameness. Three horses were lost to follow-up. There was no statistical difference between the outcomes of horses treated acutely (<24 h) or after a 24-h delay. Similarly, the involvement of synovial structures in the wound did not significantly influence outcome.
Conclusions   In this study, wounds involving the pastern and foot that were treated with a phalangeal cast carried a good prognosis for soundness (89.4%) and cosmetic healing (89.5%). The phalangeal casts were well-tolerated and effective.     

Measurement of caprine plasma beta-mannosidase with a p-nitrophenyl substrate

Experimental conditions for measuring caprine plasma beta-D-mannosidase activity are described with p-nitrophenyl-beta-D-mannopyranoside as a substrate. The plasma enzyme was stable for 3 months at -20 C or 1 week at 4 C. The optimal pH for activity was 5.0 in citrate-phosphate or acetate buffer. Enzyme activity was linear with time up to 24 hours at 37 C, but incubation of plasma at 56 C for 5 minutes resulted in loss of all activity. The apparent Michaelis-Menten constant (Km) for the plasma enzyme was 10.0 mM. Plasma beta-mannosidase from clinically normal and beta-mannosidosis carrier goats did not differ with respect to pH optimum, heat stability, or Km. The coefficient of variation for the assay, determined by assaying a plasma pool over a 3-month period, was 10.7% (mean: 115 nmole of p-nitrophenol formed/hour/ml of plasma). The assay described can be used to evaluate plasma beta-mannosidase measurements as a test for detecting carriers of caprine beta-mannosidosis, a newly described lysosomal storage disease.     

Caprine alpha- and beta-mannosidase activities: effects of age, sex, and reproductive status and potential use in heterozygote detection of beta-mannosidosis

Effects of age, sex, and reproductive status on caprine plasma alpha- and beta-mannosidase activities were studied. The potential use of these plasma assays was evaluated for heterozygote detection of caprine beta-mannosidosis in populations of control goats and a breeding herd composed of known and putative heterozygotes for beta-mannosidosis. In the control population, the mean plasma alpha- and beta-mannosidase activities decreased in both sexes with maturity. Male goats generally had higher plasma mannosidase activity than did females, and plasma beta-mannosidase activity was affected by the reproductive status of the goats examined. Although putative carriers in the beta-mannosidosis breeding herd could not be differentiated from age- and sex-matched controls, known carriers had plasma beta-mannosidase values intermediate between those of control and affected goats. The lack of any correlation between alpha- and beta-mannosidase activities excluded alpha-mannosidase as a reference enzyme for carrier detection, but there are still differences between known carriers and the control population with respect to the alpha- and beta-mannosidase ratio.     

Clearance of para-aminohippuric acid in wethers consuming locoweed

AIM: To validate the use of para-aminohippuric acid (PAH) as a marker for measuring blood flow in wethers consuming a mixed diet of locoweed and blue grama hay.

METHODS: Fourteen sheep, stratified by bodyweight (BW), were assigned to one of three treatments: 0.8 mg swainsonine (SW)/kg BW (HI), 0.2 mg SW/kg BW (LO), and no SW (Control). Sheep were fed various ratios of locoweed and blue grama hay to deliver SW treatments, for 28 days prior to infusion of PAH. Concentrations of SW and activities of alkaline phosphatase (Alk-P) and aspartate aminotransferase (AST) in serum were measured to confirm exposure to SW and subclinical intoxication. A single 20-ml injection of 5% PAH was delivered into the jugular vein after subclinical intoxication had been achieved. Blood samples were collected and serum analysed for PAH immediately prior to injection, then every 5 min from 5–30 min, and every 10 min from 30–60 min, following injection of PAH.

RESULTS: Effective delivery of SW was evident from the greater concentrations of SW measured in the serum of HI compared with LO animals (p<0.05). No significant differences were detected in the rate of elimination (range 0.097–0.108 L/min), elimination half-life (range 6.62–7.24 min), apparent volume of distribution for the central compartment (range 7.14–9.72 L), and clearance (range 0.73–0.92 L/min) of PAH, between treatments.

CONCLUSIONS: Subclinical intoxication with SW did not affect the pharmacokinetics of PAH. Thus, use of downstream dilution of PAH is a valid method to determine the rate of blood flow in nutrient flux experiments that involve consumption of locoweed.     

Sequential bacteriological observations in relation to cell-mediated and humoral antibody responses of cattle infected with Mycobacterium paratuberculosis and maintained on normal or high iron intake

Twenty calves were orally infected with Mycobacterium paratuberculosis before weaning. Ten of these plus 4 non-infected controls were maintained on elevated dietary iron intake from 6 to 33 months of age. During this time, in which the majority of animals were bred, the influence of increased dietary iron upon tests of cellular and humoral immune responsiveness to antigens of the organism were monitored. Results were examined in relation to the organism's capacity to multiply and infect up to 7 portions of the intestinal tract. No significant differences were detected in the degree of intestinal disease or pattern of faecal excretion of M. paratuberculosis in iron supplemented and non-supplemented cattle. Cutaneous delayed-type hypersensitivity (DTH) to johnin PPD developed at 1 month and in-vitro lymphocyte and immunostimulatory activity (LS) to this antigen at 2 months after infection. LS indices were significantly reduced in magnitude in iron-supplemented cattle (p less than 0.01). Most ELISA antibody responses were positive 10 to 17 months after infection and preceded the fewer number of CF responses by several months. Neither of the antibody tests was affected by elevated iron intake. Generally, complete or partial resistance to paratuberculosis was associated with sustained positive monthly LS tests (index greater than or equal to 2.0), whereas antibody levels tended to be sustained only in the more severely affected cattle. Although neither test system was affected by pregnancy the ELISA failed to detect a significant proportion of cattle chronically shedding M. paratuberculosis in faeces.