Comparison of HPLC methods for determination of anthocyanins and anthocyanidins in bilberry extracts

An HPLC method and an acid hydrolysis HPLC method for the analysis of anthocyanins and anthocyanidins in bilberry extracts have been developed. The HPLC method coupled with a mass detector has identified 11 anthocyanins in bilberry extracts. The method provides anthocyanin profiles that are very useful in verifying the identity of botanical raw materials, monitoring the consistency of the raw material source, and quantitating the total anthocyanins. The acid hydrolysis HPLC method greatly simplifies the anthocyanin profile in bilberry samples and converts anthocyanins to five major anthocyanidin aglycones: delphinidin, cyanidin, petunidin, peonidin, and malvidin. Each of these aglycones can be separated completely and quantitated accurately with external standards. Various extraction and hydrolysis conditions were investigated, and the advantages and disadvantages of the HPLC and acid hydrolysis methods are discussed.     

Chemical analysis of bovine and porcine vitreous humors: correlation of normal values with serum chemical values and changes with time and temperature

Vitreous humors collected from cattle and swine at time of death were compared with serum samples collected before these animals were slaughtered to determine whether vitreous chemical constituents were stable after death occurred. Vitreous humor from 1 eye and serum were obtained from each of 120 cattle and 120 swine at slaughter. The second eye from each animal was enucleated and incubated at 4 C, 20 C, and 37 C for 6, 12, 24, and 48 hours, and then vitreous humor was obtained from the incubated eye. Serum and the fresh and incubated vitreous samples were analyzed for urea nitrogen, creatinine, sodium, potassium, calcium, magnesium, chloride, and phosphorus concentrations. In the incubated vitreous sample, stability varied for urea nitrogen, creatinine, sodium, calcium, magnesium, and chloride concentrations, but the values were generally more stable with samples incubated at lower temperatures and for shorter incubation periods. Potassium and phosphorus concentrations increased with time and temperature of incubation of the samples.     

Canine stress syndrome/malignant hyperthermia susceptibility: calcium-homeostasis defect in muscle and lymphocytes

This study provides the first comprehensive characterisation of the calcium (Ca) homeostasis defects found in muscle and lymphocytes of a malignant hyperthermia (MH)-susceptible dog. Novel findings regarding this dog are reported, compared to controls. First, a canine stress syndrome occurs, analogous to the porcine stress syndrome; susceptibility can be identified by exercise challenge testing. Secondly, caffeine causes Ca release from muscle sarcoplasmic reticulum in a greater amount and at a greater rate. Thirdly, there is a compensatory increase in Ca sequestration by sarcoplasmic reticulum. Fourthly, lymphocytes have lower cytosolic-free Ca and a greater ability to prevent Ca increase. Halothane increases Ca by a greater amount and rate. Fifthly, muscle is more resistant to the contracture-producing effects of caffeine, as occurs in the non-rigid variant of MH susceptibility in man. This resistance, despite increased caffeine-induced release through the Ca channel, may be attributable to increased Ca sequestration by sarcoplasmic reticulum. Finally, erythrocyte osmotic fragility and creatine kinase tests fail to distinguish between the MH-susceptible dog and controls.     

SCINTIGRAPHIC ASSESSMENT OF DISTAL EXTREMITY PERFUSION IN 17 PATIENTS

To assess the role of scintigraphic evaluation of distal limb perfusion, the medical records and scintigraphic perfusion images of 17 animals(8dogs, 2cats, 2calves, 4birds and 1 ferret) with clinical signs of distal limb ischemia were examined retrospectively. Images were obtained at 5 and 10 minutes following injection of ^99m Tc-MDP, or ^99mTc-DTPA. The initial scintigraphic diagnoses of 17 animals included complete ischemia(8/17), partially reduced perfusion(5/17), and normal to increased perfusion(4/17). In 4 of the animals with partially reduced perfusion, follow-up scans indicatd progression to complete ischemia(1/4) or normal to increased perfusion(3/4). Nine of 17 animals had a final scintigraphic diagnosis of complete distal limb ischemia, and these animals were either euthanized(5/9)or had limb amputation(4/9).A final diagnosis of complete ischemia was supported with either repeat scanning(3/10), continued clinical observation(6/10)and /or pathological examination(10/10).Clinical Scintigraphy provided a safe and noninvasive assessment of distal limb perfusison, which corresponded with clinical outcome.     

Finishing lamb performance responses to bovine and porcine somatotropins administered by Alzet pumps.

Daily injection of ovine and bovine somatotropin (oST and bST, respectively) has been shown to improve performance and carcass quality of finishing lambs. To evaluate responses to continuously released bST and porcine ST (pST), which have 99 and 91% sequence homology with oST, respectively, finishing lambs were implanted with 2-wk Alzet pumps containing bST or pST, which was released at rates of 2 or 4 mg/d. Six-week growth rate and feed efficiency responses to bST were greater than those to pST (P less than .05). Overall feed efficiency was improved 15% and growth rate was increased 16% in lambs treated with 4 mg/d of bST compared with control lambs and neither trait was affected in pST-treated lambs. Performance responses were reflected by changes in circulating glucose, blood urea nitrogen, and insulin-like growth factor I (IGF-I) concentrations. Scatchard analysis of sera with relative binding of greater than 30% revealed that average binding capacities and affinities of pST-treated lambs were 7.0 mg/liter and 6.0 x 10(9) liters/mol, respectively, and of bST-treated lambs were .8 mg/liter and 1.3 x 10(9) liters/mol, respectively. In addition, lambs with high-capacity pST antibodies had lower 6-wk IGF-I concentrations than those of controls, suggesting that these antibodies may have been attenuating responsiveness to pST. It is concluded that continuously released bST, but not pST, improves performance of finishing lambs.     

Histologic comparison of canine skin biopsies collected using monopolar electrosurgery, CO2 laser, radiowave radiosurgery, skin biopsy punch, and scalpel

OBJECTIVE: To compare the histologic appearance of canine skin biopsies collected by use of a scalpel, skin biopsy punch, monopolar electrosurgery, CO2 laser, and radio wave radiosurgery in fully rectified wave form (RWRS). STUDY DESIGN: Experimental, randomized design. ANIMALS: Healthy adult grayhounds (n=4). METHODS: Skin biopsies were collected using 5 techniques. Cut margins of biopsy specimens and adjacent peripheral skin were evaluated using light microscopy to compare penetration of the dermis by tissue carbonization (char). RESULTS: No char occurred in skin specimens collected by biopsy punch and scalpel. Char penetration occurred in all specimens collected by electrosurgery, CO2 laser, and RWRS. Mean char penetration in skin biopsies collected by RWRS (0.158 mm) was significantly less than for monopolar electrosurgery (0.223 mm) and CO2 laser (0.215 mm). Mean char penetration in adjacent peripheral skin surrounding biopsies collected by RWRS (0.171 mm) was significantly less than monopolar electrosurgery (0.255 mm) but not less than CO2 laser (0.215 mm, P<.07). CONCLUSIONS: RWRS (blended waves in cut-coagulate mode) caused less lateral thermal damage to canine skin biopsies than monopolar electrosurgery and CO2 laser and less lateral thermal injury to peripheral skin than monopolar electrosurgery. CLINICAL RELEVANCE: Excision of canine skin biopsies with heat-generating devices may not allow reliable histologic interpretation, particularly when assessing margins of small biopsy specimens. RWRS may be less traumatic to canine skin than monopolar electrosurgery and CO2 laser when used to make incisions.