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Biomedical subjects

S K Jensen

Publications and source records attributed to S K Jensen.

At least 19 recordsLinked to original sources

Tocopherols, retinol, beta-carotene and fatty acids in fat globule membrane and fat globule core in cows' milk.

Milk fat globule membranes (MFGM) were isolated from milk from cows injected intraperitoneally with dl-alpha-tocopherol acetate. The fatty acid composition and content, and the contents of tocopherols, retinol and beta-carotene were determined and compared with the composition and content in the original cream sample. Intraperitoneal injection of 10 g dl-alpha-tocopherol acetate elevated the alpha-tocopherol content in the milk fat from 13-30 to 50-70 micrograms alpha-tocopherol/g milk fat 2-3 d after injection. The increase depended on the alpha-tocopherol status of the cow prior to injection. The concentrations of retinol and beta-carotene in the milk fat were unchanged after the alpha-tocopherol injections. MFGM fatty acids made up 18-27 g/kg total fatty acids in the milk fat. However, the proportions of monounsaturated and polyunsaturated fatty acids were higher in MFGM than in total milk fat, while the proportion of saturated fatty acids was lower in MFGM (P < 0.001). Thus, the long-chain polyunsaturated fatty acids in MFGM constituted approximately 40-70 g/kg total milk fat. alpha-Tocopherol was the only fat-soluble vitamin detected in MFGM; gamma-tocopherol, retinol and beta-carotene were detected only in the cream. A significant relationship between alpha-tocopherol contents in cream and MFGM was found: (alpha-tocopherol in MFGM fatty acids) = -1652 x (1/ln(alpha-tocopherol in cream fatty acids)3) + 97 (r = 0.857, P < 0.001) when the contents of alpha-tocopherol were expressed as microgram/g fatty acid. According to this equation the upper limit for incorporation of alpha-tocopherol into MFGM is 97 +/- 5 micrograms/g MFGM fatty acids. Thus, under normal farming conditions the alpha-tocopherol content will be highest in MFGM. However, in cream with an alpha-tocopherol concentration < 15 micrograms/g cream fatty acids the concentration in MFGM will be lower and furthermore will decrease rapidly. The possible importance of this relationship in relation to the oxidation of milk fat is discussed.

Animals

Exocrine pancreatic secretions in growing pigs fed diets containing fish oil, rapeseed oil or coconut oil.

Two experiments were performed to study the effect of feeding diets containing oils with different fatty acid composition on exocrine pancreatic secretions in growing pigs using two different methods to collect pancreatic juice. In the first experiment, three barrows (initial weight 37 kg) were fitted with a pancreatic pouch re-entrant cannula. An isolated pouch was prepared where the pancreatic duct enters the duodenum. In the second experiment, also using three barrows (initial weight 32 kg), a catheter was inserted into the pancreatic duct. Three wheat starch and fish meal-based diets were formulated to contain either 15 g fish oil, rapeseed oil or coconut oil/100 g. In both experiments, the diets were fed according to a 3 times 3 Latin square design. The volume of pancreatic juice secreted, pH and secretion of bicarbonate, protein, amylase, trypsin, lipase and colipase were not significantly affected by the diets in the first experiment. In the second experiment, chymotrypsin secretion was significantly greater in pigs fed the coconut oil diet, and secretion of carboxyl ester hydrolase was significantly higher in pigs fed the fish oil diet. When compared qualitatively, pigs in Experiment 2 secreted more pancreatic juice; the pancreatic juice had a higher pH, and trypsin, carboxyl ester hydrolase and colipase secretions were substantially higher whereas amylase secretion was lower than for pigs in Experiment 1. The fatty acid composition of the different oils had minor effects on exocrine pancreatic secretion in growing pigs. However, there were considerable differences between the two surgical methods used to collect pancreatic juice, and these differences may be explained by physiological changes induced by the two methods.

Amylases

Inclusion of oxidized vegetable oil in broiler diets. Its influence on nutrient balance and on the antioxidative status of broilers.

Over a period of 4 wk, 24 10-d-old broiler hens were fed diets containing 11% vegetable oil (9% rapeseed oil, 2% soybean oil), which was added either fresh (1 meq O2/kg oil) or oxidized (156 meq O2/kg oil). The effects of the dietary treatments on nutrient digestibility were examined in a balance experiment. The antioxidative status of the animals was evaluated using plasma concentrations of thiobarbituric acid-reactive substances (TBARS), erythrocyte hemolysis in vitro, selenium-dependent and selenium-independent activity of glutathione peroxidase in liver cell cytosolic fractions, and concentrations of tocopherols and other fat-soluble compounds with antioxidative properties (lutein, beta-carotene, and retinol) in plasma and various tissues (skeletal muscle, cardiac muscle, liver, and abdominal fat). Compared to the fresh oil, the concentrations of linoleic and linolenic acid were slightly lower in oxidized oil. The concentration of alpha-tocopherol in the diet with fresh oil was an average of 80.8 mg/kg diet, whereas the diet with oxidized oil only provided 44 mg/kg. The dietary selenium content averaged 0.48 mg/kg in both diets. During the experiment, none of the animals showed symptoms of diarrhea or vitamin E deficiency. The intake of oxidized oil caused a growth depression after 2 wk. The retention of fat (P = 0.07), energy (P = 0.09), and alpha-tocopherol (P < 0.01) was lower in the group fed oxidized fat. Furthermore, these animals showed significantly higher plasma concentrations of TBARS (P < 0.01), and lower concentrations of tocopherols, lutein, beta-carotene, and retinol in plasma and tissues.

Adipose Tissue

Supplementation of broiler diets with all-rac-alpha- or a mixture of natural source RRR-alpha-,gamma-,delta-tocopheryl acetate. 1. effect on vitamin E status of broilers in vivo and at slaughter.

A total of 300 female broiler chickens were reared from day-old to 10 d of age on the same starter diet. Then they were divided into five groups, receiving a control diet (Group 1) relatively rich in fat (14.3%) and unsaturated fatty acids (87.6%) and standardized with respect to vitamins and minerals, supplemented with 100 mg (Group 2) and 500 mg (Group 4) of RRR-alpha-,gamma-,delta-tocopheryl acetate/kg feed (40.6% alpha-, 41.1% gamma-, 18.3% delta-) or 100 mg (Group 3) and 500 mg (Group 5) all-rac-alpha-tocopheryl acetate/kg feed until slaughter at 6 wk of age. No differences between the supplemented groups were observed with respect to weight gain, feed consumption, packed cell volume (PCV), plasma enzyme activities of creatine kinase (CK) and glutathione peroxidase (GSH-Px), fatty acid composition, and enzyme activities of citrate synthase (CS), and total lactate dehydrogenase (LDH), and 3-OH-acyl-coenzyme A-dehydrogenase (HAD) of breast (Pectoralis major) and thigh (Gastrocnemius interna) muscle. Increasing levels of alpha-, gamma-, and delta-tocopherol were found in blood plasma with increasing dietary levels of these tocopherols. Only alpha-tocopherol was detectable in skeletal muscle and in higher concentrations in thigh than in breast muscle. Hemolysis in vitro and plasma activity of aspartate aminotransferase (ASAT) were lower (P < .01) in Groups 2 and 4 than in Groups 3 and 5. Interactions were observed between dietary type and concentration of tocopherols for plasma CK, GSH-Px, Na+, and K+. No measurable excretion of ethane and pentane was observed in any of the groups. The findings indicate that the oxidative stress in the live animals was minimal. The mixture of natural source RRR-alpha-,gamma-,delta-tocopherols was as efficient in protecting the live chickens as the all-rac-alpha-tocopheryl acetate, when provided on a weight basis as judged from the chosen in vivo parameters of vitamin E status.

Abattoirs

Retinol determination in milk by HPLC and fluorescence detection.

A simple and rapid method for determination of retinol in whole milk is described. Milk (400 mg) was diluted with a water-methanol-ethanol mixture (55:9:36 by vol.) and saponified with potassium hydroxide in a culture tube. Retinol was extracted into 10 ml heptane-di-isopropyl ether (3:1) of which 100 microliters was injected into the HPLC. Fluorescence detection ensured the specificity and sensitivity. The critical points in the analysis were the extraction of retinol from fatty samples and the instability of retinol towards photo-oxidation and air oxidation in alkaline solvents. There was an average recovery of 98.5 +/- 2.4% and a CV of 3.6%.

Animal Feed

[Stretching in relation to sports and prevention of injuries].

Stretching is a regular item in training programmes and it is employed to increase flexibility, to prevent muscle tenderness, overuse injuries and strains. Stretching is carried out by stretching muscles and connective tissue to the extreme positions of joints. A review of stretching exercises based on the literature is presented in relation to prevention of injuries. The various techniques employed are reviewed.

Athletic Injuries

Symptoms and signs predictive of the voiding pattern after acute urinary retention in men.

Over a 9-month period 228 men were admitted for acute urinary retention to six different casualty wards in the Copenhagen area. The patients were followed in the corresponding urological departments for one year. Twenty-seven variables were registered for each patient. The cumulative rate of recurrent retention was 56% after one week and 68% after one year. Factors predictive of preserved voiding ability were a retained volume less than 500 ml, a known event provocative of acute retention, and a maximum flow rate of more than 5 ml/s after the retention. The maximum flow rate measured within the first week after the retention was reliable within the follow-up period if the voided volume was 150 ml or more. The etiology of the acute retention was infravesical obstruction in 90% of the patients, and 85% required subsequent surgical treatment. Predictive of surgical treatment for infravesical obstruction were recurrent urinary retention within one week, a volume of retention of more than 500 ml, the absence of a provocative situation prior to the retention episode and nocturia twice or more.

Acute Disease

Acute urinary retention in women: a prospective study of 18 consecutive cases.

Over a 9 month period 18 women were admitted for acute urinary retention to six different Copenhagen hospitals, serving a population of approximately 700,000 people. Urodynamically 9 patients had underactive detrusor function, 2 had infravesical obstruction and 3 had both underactive detrusor function and infravesical obstruction. In 4 patients bladder and urethral function were not classified. In 10 patients a provocative event preceded the retention episode. Eleven patients developed recurrent retention within 3 months and 7 patients had persistent severe obstructive voiding problems. Best prognosis was found for patients with correctable infravesical obstruction and for patients with minimal symptoms prior to the retention episode.

Acute Disease

Administration of a retinoid as prophylaxis of recurrent non-invasive bladder tumors.

A controlled study has been conducted to ascertain whether administration for 8 months of a vitamin A-acid analog, Tigason, could prevent recurrences of non-invasive bladder tumors. Eligible were 73 patients, 33 in the Tigason group, and 40 in the placebo group. The results indicate that Tigason, as used in this study, is ineffective as prophylaxis. Side effects to Tigason urged 17 patients to drop out from the study mostly due to symptoms from skin and mucous membranes. The discussion considers different reasons for the lack of effect and concludes that more tolerable vitamin A-acid analogs are needed if further studies of prevention of non-invasive bladder tumors are to be carried out.

Antineoplastic Agents

Fournier's gangrene presenting as gas-forming subcutaneous infection of the scrotum.

Two cases of gas-forming Fournier's gangrene were recently treated in a urology department. The etiology, pathology, bacteriology and treatment of Fournier's gangrene are discussed. An aggressive attitude with respect to both surgery and antibiotic therapy is recommended as possible means of reducing the high mortality associated with the condition.

Anti-Bacterial Agents

Cefotaxime for prevention of infectious complications in bacteriuric men undergoing transurethral prostatic resection. A controlled comparison with methenamine.

Forty-two men with urinary tract infection and benign prostatic hyperplasia were randomized into two groups before transurethral resection. One group (22 patients) received Claforan (cefotaxime) peroperatively and thereafter daily for five days. In the other group (20 patients), Hiprex (methenamine hippurate) was given daily from the day before the operation, for a total of six days. All the bacterial isolates were sensitive to cefotaxime. The efficacy of the medication was clinically and bacteriologically evaluated. Postoperative temperature elevation (greater than 38 degrees C) occurred in one of the 22 patients in the cefotaxime group, and in nine of the 20 in the methenamine hippurate group (p less than 0.05). None of the former group, but two patients in the latter, had septicemia. The difference was not statistically significant. The response to treatment was satisfactory in 13 of the 22 patients in the cefotaxime group, but in only one of the 20 treated with methenamine hippurate (p less than 0.005). Antibiotic treatment is recommended for bacteriuric patients undergoing transurethral prostatic resection.

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