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The dual stable isotope method with a timed 24-h urine collection is the gold standard approach to measure fractional calcium absorption. However, the need to collect urine for 24 h makes this technique time-consuming and laborious. Our study sought to determine whether a dual isotope method using a single serum sample obtained 4 h after administration of the initial isotope provides a useful approach to measure fractional calcium absorption. Following a metabolic diet with a fixed calcium intake of 30 mmol/day for 10 days, nineteen healthy subjects age 54-74 were given a test meal with an oral isotope ((44)Ca) followed 2 h later by an intravenous isotope ((42)Ca). Once the oral isotope was administered, urine was collected for 24 h, and a serum sample was obtained after 4 h. The ratio of the oral to intravenous isotopes was measured in the urine and serum by mass spectroscopy. Fractional calcium absorption was 16.2 ± 7.7% by the 4-h single serum method versus 18.5 ± 7.5% by the 24-h urine method. There was a small mean difference between the urine and serum methods of 2.33% with a confidence interval -3.97 to 8.60%. The two methods showed a strong linear association (r = 0.912, p<0.001). Use of dual stable isotopes with a 4-h single serum method gives fractional calcium absorption values that are 12.5% lower than with the 24-h urine method; however, it rank orders subjects accurately thus making it a useful alternative method in clinical research applications.

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UNLABELLED: In 17 adults on a fixed metabolic diet, an 11-day course of cinacalcet increased serum gastrin and basal gastric acid output, but not maximal gastric acid output, compared with a placebo. These findings indicate that the calcium sensor receptor plays a role in the regulation of gastric acid. INTRODUCTION: Gastric acid secretion is a complex process regulated by neuronal and hormonal pathways. Ex vivo studies in human gastric tissues indicate that the calcium sensing receptor (CaR), expressed on the surface of G and parietal cells, may be involved in this regulation. We sought to determine whether cinacalcet, a CaR allosteric agonist, increases serum gastrin and gastric acid secretion. METHODS: Seventeen healthy adults with normal gastric acid output were placed on an 18-day metabolic diet. On day 8 (baseline), participants were given cinacalcet (15 then 30 mg/day) or placebo for 11 days. Changes in gastric acid output, serum gastrin, and other measures were compared in the two groups. RESULTS: Changes in serum gastrin and basal acid output (adjusted for baseline body weight) were significantly more positive in the cinacalcet group compared with placebo (P = 0.004 and P = 0.039 respectively). Change in maximal acid output was similar in the two groups (P = 0.995). As expected, cinacalcet produced significant decreases in serum PTH (P < 0.001) and ionized calcium levels (P = 0.032), and increases in serum phosphorus levels (P = 0.001) and urinary calcium (P = 0.023). CONCLUSIONS: This study provides in vivo evidence that activation of the CaR increases serum gastrin levels and basal gastric acid secretion in healthy adults.

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UNLABELLED: In 30 adults, increasing intake of aromatic amino acids increased calcium excretion and serum IGF-1, but not indices of bone turnover, when compared with similar increases in intake of branched-chain amino acids. The mechanisms involved are not certain but these findings suggest a role for the calcium sensor receptor. INTRODUCTION: In contrast to branched-chain amino acids (BCAAs), aromatic amino acids (AAAs) bind to the calcium sensing receptor (CaR) and thus have an increased potential to affect calcium homeostasis. In this study we compare the effects of increased intake of AAAs versus BCAAs on calcium excretion, serum IGF-1, markers of bone turnover, and 4-hr calcium excretion after an oral calcium load. METHODS: After two weeks on low-protein metabolic diets, 30 healthy subjects were randomized to a fivefold increase in intake of AAAs or BCAAs for two weeks. Changes in calcium excretion and other measures were compared in the two groups. RESULTS: With the increase in amino acid intake, 24-hr calcium excretion (P = 0.027), IGF-1 (P = 0.022), and 4-hr calcium excretion after an oral load (P = 0.023) increased significantly in the AAA relative to the BCAA group. Group changes in turnover markers did not differ significantly. CONCLUSION: In comparison with BCAAs, AAAs promoted calcium excretion. The calciuria does not appear to result from increases in bone resorption and may occur by increasing calcium absorption. The AAAs also increased circulating levels of IGF-1. Collectively these findings raise the possibility that AAAs may selectively influence calcium homeostasis through their interactions with the CaR.

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In 1995 all surgical departments in Denmark were asked to reply to a questionnaire about their use of postoperative thromboprophylaxis. Response rate was 95%. Ninety-two percent of the departments performing major surgery routinely used prophylaxis, in 84% of these according to prior written instructions, but still only 36% use prophylaxis in emergency surgery. The indications and methods used are in accordance with recommendations in the literature. The use of aspirin as prophylaxis against venous thromboembolism should be avoided, and the use of prophylaxis in emergency surgery should be improved. The most commonly used method was low molecular weight heparin (82%) often in combination with graduated elastic stockings. There is no longer any doubt about the need for prophylaxis. The tasks of the future are to identify the risk groups and establish the duration of prophylaxis.

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UNLABELLED: In order to investigate the educational value of trainee surgeons' work, all work done by trainees at a Department of Surgery was recorded in a prospective and consecutive way for four weeks. It was recorded as fixed categories divided into intervals of 15 minutes. The work could be classified in three dimensions: Character, educational value and geography. The youngest trainees performed routine work without educational value. They had some practical jobs which could be done by other personnel. The work did not fulfil the educational claims for a trainee surgeon in phase I. The second group of trainees performed much routine work without educational value. They had no practical jobs that could have been performed by non-doctors. They had some work with educational value but not enough to fulfil the goals of a trainee surgeon in phase II. CONCLUSION: Doctors' clinical education could be improved by giving them work with educational value and supervision. Supervision should be performed by specialists who should also contribute to the routine work without educational value.

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On the basis of recent findings that adult black women had similar calcium absorption but higher levels of 1,25-dihydroxyvitamin D [1,25-(OH)2D] than white women, we hypothesized that blacks have a gut resistance to the action of calcitriol. To test this, we studied 11 black [age, 32.4 +/- 5.7 (+/- SD) yr] and 12 white women (28.4 +/- 5.5 yr). The women were maintained on a constant 500-mg calcium diet for 4 weeks, and each received calcitriol (0.25 microgram) four times daily for the last 2 weeks. After 2 and 4 weeks, each subject had measurements of fractional 45Ca absorption index and blood and urine tests. At 2 weeks, the black women had similar calcium absorption indexes [18.7 +/- 1.9% (+/- SEM)/L vs. 20.0 +/- 1.8%/L; age adjusted], borderline higher 1,25-(OH)2D levels [95.7 +/- 6.4 (+/- SEM) vs. 78.2 +/- 6.2 pmol/L; P = 0.071; age adjusted], higher serum PTH levels, and lower urinary calcium excretion. Calcitriol therapy induced similar increments in plasma 1,25-(OH)2D levels in the two groups, but a smaller increment in calcium absorption in the black women (18.4 +/- 8.6% vs. 44.6 +/- 7.8%; P = 0.043; means adjusted for age and initial absorption index). These findings support the hypothesis that, compared with whites, healthy premenopausal black women have gut resistance to the action of calcitriol.

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The Massachusetts Dietetic Association implemented a statewide retrospective quality assurance audit to determine the effectiveness and cost of medical nutrition therapy in patients with hypercholesterolemia (> 5.20 mmol/L). Hypercholesterolemia is a major risk factor for coronary artery disease (CAD). Data were collected at 23 sites from 285 outpatients seen by a registered dietitian for a minimum of two visits. Patients taking lipid-lowering medications were excluded. Of the 285 patients, 108 (38%) were men and 177 (62%) were women. The mean age was 51.4 years (range = 22 to 79 years). Results showed that the mean reduction in serum cholesterol level was 8.6%, which translates to a decrease of approximately 17.2% in risk of CAD. Forty-five percent of the total population showed an 11% or greater reduction in serum cholesterol levels. Reduction in serum cholesterol levels correlated with increased time spent with a dietitian (r = .188, P < .001). The mean cost for nutrition intervention with a dietitian was $163 (a mean of four visits). In contrast, the estimated annual cost of treatment for patients with hypercholesterolemia using drug therapy is $1,450. A 1993 report calculated the annual cost of treating heart disease in the United States to be $80 billion. Medical nutrition therapy should be considered the initial, effective, and low-cost approach in the management of patients with mild to moderate hypercholesterolemia.

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Sixty-one surgical departments in Denmark were asked how they used the three possible diagnoses: carcinoma in situ vesicae urinariae (D09.0), neoplasma benignum vesicae urinariae (D30.3) and neoplasma malignum vesicae urinariae (C67.9) for bladder tumours with specific reference to different stages and grades of the tumour. The answers from 59 departments demonstrated great variation in the classification of the same bladder tumour. This variation results in a registration of data which is not valid for a statistical outcome of the real incidence of benign and malignant bladder tumours in Denmark. A consensus from the Danish Bladder Cancer Committee, which will be published in 1996, concerning the criteria for the use of the different diagnoses for bladder tumours, should however in the future make it possible for all departments to make a uniform classification.

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OBJECTIVE: To summarize and evaluate the progress in the current practices of thromboprophylaxis (TP) in Danish surgical departments. DESIGN: Summary of three questionnaire surveys in 1981, 1985 and 1990. SUBJECTS/SETTING: Hospital departments performing general, orthopaedic or gynaecological surgery in Denmark. MAIN OUTCOME MEASURES: Development or routine employment of TP, standard instructions for TP, indications and methods for TP. RESULTS: Replies were obtained from 85%-92%. During the period the overall use TP increased from 89% of the departments in 1981 to 93% in 1985 to 96% in 1990 (p = 0.03). The use of TP according to standard instructions increased from 50% over 54% to 68% (p = 0.001). Heparin is the drug of choice in 95% and graded compression stockings in 70% of the departments. Only 36% of the departments routinely use TP in emergency surgery. CONCLUSIONS: The development in attitudes towards TP in Denmark complies with the scientific evolution. Methods and indications correspond with the recommendation of the literature and international consensus conferences. However, the low rate of TP in emergency surgery is unsatisfactory, and the use of acetylsalicylic acid as postoperative venous thromboprophylaxis should stop. The authors emphasize the introduction of firm standard instruction for TP in all surgical department. A continuous evaluation of the use of TP in Danish surgical department by means of quality assurance studies is recommended.

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Perineal hernia after abdominoperineal extirpation of the rectum is a rare condition. The most common symptom is perinea/discomfort and bulging. This condition most often develops within a year after extirpation of the rectum. In order to prevent perineal hernia great effort should be taken when closing the peritoneum and the muscular layer towards the pelvic cave. Several repair operations have been proposed in the literature. The authors recommend a transabdominal approach, possibly with interposition of a synthetic mesh. If the perineal skin is damaged, a combined approach with both transabdominal and perineal access should be used.

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Black-white differences in calcium metabolism are sought because they may reveal why blacks have higher bone mass than whites. Comparative studies of calcium absorption in blacks and whites are not available. In this study, we compare fractional calcium retention, an index of calcium absorption, and calcium regulating hormone levels in black and white women on a high-calcium diet and after adaptation to a low-calcium diet. A total of 30 healthy women (15 black and 15 white) had measurements of fractional 47Ca retention and calcium regulating hormone levels after 8 weeks on a 2000 mg calcium diet and, subsequently, after 1, 2, 4, and 8 weeks on a 300 mg calcium diet. By 2 weeks after the diet change, fractional 47Ca retention, parathyroid hormone (PTH), and 1,25-dihydroxyvitamin D [1,25-(OH)2D] had reached a plateau at higher levels, urine calcium at a low level, and serum calcium at the same level (repeated-measures ANOVA). Fractional 47Ca retention, serum calcium, and PTH were similar on both diets in blacks and whites. Blacks had higher levels of 1,25-(OH)2D on both diets (e.g., 125.1 +/- 53.5 SD versus 73.4 +/- 19.0 pmol/liter, P = 0.003 on low-calcium diet) and a greater increase in 1,25-(OH)2D after the diet change (33.9 +/- 30.1 SD versus 11.8 +/- 17.9 pmol/liter, P = 0.021). Serum phosphorus was lower in blacks throughout. For hormone levels and fractional calcium retention to stabilize after a diet change, 2 weeks was needed.(ABSTRACT TRUNCATED AT 250 WORDS)

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In a questionnaire survey among surgical hospital departments in Denmark (1990), we assessed the attitudes and practices of use of postoperative thrombosis prophylaxis (TP). Replies were obtained from 92% of departments. Otological and odontological departments seldom used TP. Among departments performing major surgery a total of 88% used TP routinely (general surgery: 91%, orthopedic surgery: 94%, gynecology: 84%). 68% of these departments used TP according to written instructions. Indications for TP, and methods used, are in accordance with the literature, except for the use of TP in emergency surgery (routine in 36% of departments only), or for the continued use of aspirin for TP in 13% of departments.

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UNLABELLED: Pneumoperitoneum results from a perforation of the gastrointestinal tract in the majority of instances and the necessity for surgery is involved. In some cases with monosymptomatic pneumoperitoneum, surgery is unnecessary. A case of a man aged 64 with great amount of free intraperitoneal air is presented. The patient was clinically unaffected and had neither fever nor signs of peritoneal affection. The intraperitoneal air decreased slowly and disappeared after about 60 days. A self-sealing perforation of a duodenal ulcer was the cause of pneumoperitoneum. The most common causes of non-surgical pneumoperitoneum (PP) are discussed. IN CONCLUSION: Monosymptomatic PP is not an indication for emergency surgery. If the patient has no signs of peritoneal reactions conservative treatment can be considered.

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Previous studies using spectrophotometric methods for vitamin A analysis concluded that fasting prior to blood collection is not necessary for determining vitamin A status of children or young adult subjects. We measured the effect of mixed vitamin A and carotenoid containing meals with less than 3, 50, and 100% of the recommended dietary allowance (RDA) for vitamin A on serum concentrations of retinyl esters, retinol, and carotenoids in elderly and young adults after an overnight fast. Retinyl ester concentrations rose significantly in both age groups with a numerically higher rise over baseline in the elderly subjects: 6.0 +/- 0.9 micrograms/dl for elderly (p less than 0.001), 5.0 +/- 0.5 micrograms/dl for young (p less than 0.001) at 50% RDA; 9.0 +/- 1.3 micrograms/dl for elderly (p less than 0.001) and 6.8 +/- 1.6 micrograms/dl for young (p less than 0.05) at 100% RDA. We conclude that in both young and elderly adults, but especially in the elderly, fasting conditions are necessary for the accurate assessment of vitamin A status if spectrophotometric methods are used for measuring vitamin A.

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Although fractional calcium absorption is known to vary inversely with calcium intake, the extent and timing of individual hormonal and calcium absorption responses to altered calcium intake have not been defined. We measured fractional whole body retention of orally ingested 47Ca, an index of calcium absorption, in nine normal women after they had eaten a 2000-mg calcium diet for 8 weeks and a 300-mg calcium diet for 1, 2, 4, and 8 weeks. After the diet change, serum intact PTH (32.2% increase; P = 0.005), serum 1,25-dihydroxyvitamin D [1,25-(OH)2D; 43.8% increase; P = 0.003], and fractional whole body calcium retention (42.8% increase; P = 0.004) increased within 1 week. Although the PTH and calcium retention responses remained fairly constant throughout the low calcium intake period, serum 1,25-(OH)2D concentrations declined toward baseline after week 1. Thus, the late increase in calcium retention may have resulted from calcium absorption that was independent of 1,25-(OH)2D stimulation.

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Digital vasospastic phenomena have been reported to result from use of nonselective and cardioselective beta-adrenoreceptor-blocking drugs. The effects of 80 mg/day propranolol and 100 mg/day metoprolol on finger hemodynamics and clinical responses were compared with those of placebo in 16 patients with Raynaud's phenomenon. A double-blind, 2 week crossover study design was used with a 2 week washout placebo period between drugs. Total fingertip blood flow (FBF) as determined by venous occlusion plethysmography, fingertip capillary flow (FCF) as determined by radioisotope disappearance rate, and finger systolic blood pressure (FSP) were measured in a 28.3 degrees and a 20 degrees C room at the end of each period. Subjects kept diaries to record vasospastic attacks. There were no significant changes in FBF, FCF, or FSP in the warm or cool environment during drug treatment as compared with during the placebo period. A decrease in pulse rate occurred with both drugs and there was a decrease in blood pressure with metoprolol. There were no significant changes in the number of vasospastic attacks or in the patients' overall evaluation of their conditions while they were receiving the drugs. It is concluded that the presence of Raynaud's phenomenon is not a contraindication to the use of beta-adrenoreceptor-blocking drugs in the normotensive population.

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To determine whether thromboxane A2 may be of pathogenetic importance in Raynaud's phenomenon, finger hemodynamic and clinical responses to dazoxiben, a thromboxane synthetase inhibitor, were studied in 25 subjects. Thirteen subjects had idiopathic Raynaud's disease and 12 subjects had secondary Raynaud's disease. A double-blind, 2-week crossover study design was used. Dazoxiben dose was 100 mg four times a day. Total fingertip blood flow (FBF) by venous occlusion plethysmography, fingertip capillary flow (FCF) by radioisotope disappearance rate, and finger systolic blood pressure (FSP) were measured in a 28.3 degree and a 20 degree room at the end of each period. Subjects kept diaries of vasospastic attacks. For the 25 subjects and the two subgroups, dazoxiben did not improve total FBF, FCF, or FSP. Subjects with idiopathic Raynaud's disease had a small decrease in the number of vasospastic attacks and an increase in percentage of attack-free days on dazoxiben, but in an overall evaluation by the subjects in both subgroups, dazoxiben did not improve symptoms. It is concluded that thromboxane is not of pathogenetic importance in Raynaud's phenomenon and that thromboxane synthesis inhibition is not of therapeutic benefit.

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The effect of nifedipine on fingertip hemodynamics was studied in 10 patients with Raynaud's phenomenon. Fingertip blood flow (FBF) was determined in a 20 degrees C environment by venous occlusion air plethysmography and fingertip vascular resistance (FVR) was calculated from the mean blood pressure and the FBF. Nifedipine, administered as a 10 mg sublingual dose, increased FBF in 8 of the 10 patients. FVR for the 10 patients decreased 40% from 40.7 +/- 10.8 to 24.2 +/- 6.1 U (p less than 0.05). Seven of the 10 patients were followed in a crossover placebo-controlled clinical trial. The frequency and severity of Raynaud's phenomenon was less in all seven patients when taking nifedipine as compared to placebo. Nifedipine-induced fingertip vasodilation may contribute to clinical improvement in some patients with Raynaud's phenomenon.

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