Multiple transportable carbohydrates enhance gastric emptying and fluid delivery.

This study compared the effects of ingesting water (WATER), an 8.6% glucose solution (GLU) and an 8.6% glucose+fructose solution (2:1 ratio, GLU+FRU) on gastric emptying (GE), fluid delivery, and markers of hydration status during moderate intensity exercise. Eight male subjects (age=24+/-2 years, weight=74.5+/-1.2 kg, VO2max=62.6+/-2.5 mL/kg/min) performed three 120 min cycling bouts at 61% VO2max. Subjects ingested GLU, GLU+FRU (both delivering 1.5 g/min carbohydrate), or WATER throughout exercise, ingesting 2.1 L. Serial dye dilution measurements of GE were made throughout exercise and subjects ingested 5.00 g of D2O and 150 mg of 13C-acetate at 60 min to obtain measures of fluid uptake and GE, respectively. GLU+FRU resulted in faster rates of deuterium accumulation, an earlier time to peak in the 13C enrichment of expired air and a faster rate of GE compared with GLU. GLU+FRU also attenuated the rise in heart rate that occurred in GLU and WATER and resulted in lower ratings of perceived exertion. There was a greater loss in body weight with GLU corrected for fluid intake. These data suggest that ingestion of a combined GLU+FRU solution increases GE and "fluid delivery" compared with a glucose only solution.

Role of finite populations in determining evolutionary dynamics.

The connection between the finite size of an evolving population and its dynamical behavior is examined through analytical and computational studies of a simple model of evolution. The infinite population limit of the model is shown to be governed by a special case of the quasispecies equations. A flat fitness landscape yields identical results for the dynamics of infinite and finite populations. On the other hand, a monotonically increasing fitness landscape shows "epochs" in the dynamics of finite populations that become more pronounced as the rate of mutation decreases. The details of the dynamics are profoundly different for any two simulation runs in that events arising from the stochastic noise in the pseudorandom number sequence are amplified. As the population size is increased or, equivalently, the mutation rate is increased, these epochs become smaller but do not entirely disappear.

Measurement of exogenous carbohydrate oxidation: a comparison of [U-14C]glucose and [U-13C]glucose tracers.

The purpose of this study was to assess the level of agreement between two techniques commonly used to measure exogenous carbohydrate oxidation (CHO(EXO)). To accomplish this, seven healthy male subjects (24 +/- 3 yr, 74.8 +/- 2.1 kg, V(O2(max)) 62 +/- 4 ml x kg(-1) x min(-1)) exercised at 50% of their peak power for 120 min on two occasions. During these exercise bouts, subjects ingested a solution containing either 144 g glucose (8.7% wt/vol glucose) or water. The glucose solution contained trace amounts of both [U-13C]glucose and [U-14C]glucose to allow CHO(EXO) to be quantified simultaneously. The water trial was used to correct for background 13C enrichment. 13C appearance in the expired air was measured using isotope ratio mass spectrometry, whereas 14C appearance was quantified by trapping expired CO(2) in solution (using hyamine hydroxide) and adding a scintillator before counting radioactivity. CHO(EXO) measured with [13C]glucose ([13C]CHO(EXO)) was significantly greater than CHO(EXO) measured with [14C]glucose ([14C]CHO(EXO)) from 30 to 120 min. There was a 15 +/- 4% difference between [13C]CHO(EXO) and [14C]CHO(EXO) such that the absolute difference increased with the magnitude of CHO(EXO). Further investigations suggest that the difference is not because of losses of CO2 from the trapping solution before counting or an underestimation of the "strength" of the trapping solution. Previous research suggests that the degree of isotopic fractionation is small (S. C. Kalhan, S. M. Savin, and P. A. Adam. J Lab Clin Med89: 285-294, 1977). Therefore, the explanation for the discrepancy in calculated CHO(EXO) remains to be fully understood.

No differences in cycling efficiency between world-class and recreational cyclists.

The aim of this experiment was to compare the efficiency of elite cyclists with that of trained and recreational cyclists. Male subjects (N = 69) performed an incremental exercise test to exhaustion on an electrically braked cycle ergometer. Cadence was maintained between 80 - 90 rpm. Energy expenditure was estimated from measures of oxygen uptake (VO (2)) and carbon dioxide production (VCO(2)) using stoichiometric equations. Subjects (age 26 +/- 7 yr, body mass 74.0 +/- 6.3 kg, Wpeak 359 +/- 40 W and VO(2)peak 62.3 +/- 7.0 mL/kg/min) were divided into 3 groups on the basis of their VO (2)peak (< 60.0 (Low, N = 26), 60 - 70 (Med, N = 27) and > 70 (High, N = 16) mL/kg/min). All data are mean +/- SE. Despite the wide range in aerobic capacities gross efficiency (GE) at 165 W (GE (165)), GE at the same relative intensity (GE (final)), delta efficiency (DE) and economy (EC) were similar between all groups. Mean GE (165) was 18.6 +/- 0.3 %, 18.8 +/- 0.4 % and 17.9 +/- 0.3 % while mean DE was 22.4 +/- 0.4 %, 21.6 +/- 0.4 % and 21.2 +/- 0.5 % (for Low, Medium and High, respectively). There was no correlation between GE (165), GE (final), DE or EC and VO(2)peak. Based on these data, we conclude that there are no differences in efficiency and economy between elite cyclists and recreational level cyclists.

An empirically-derived clinical placement evaluation tool: a 3-country study.

We report the development of a brief and simple-to-complete clinical placement evaluation scale. Unlike many previous attempts to develop such tools, the one reported here gives reliable numerical scores with a firm empirical foundation. The scoring correlates well between three European countries: UK, Finland, and Germany.

Higher dietary carbohydrate content during intensified running training results in better maintenance of performance and mood state.

The aim of this study was to determine whether consumption of a diet containing 8.5 g carbohydrate (CHO) x kg(-1) x day(-1) (high CHO; HCHO) compared with 5.4 g CHO x kg(-1) x day(-1) (control; Con) during a period of intensified training (IT) would result in better maintenance of physical performance and mood state. In a randomized cross-over design, seven trained runners [maximal O(2) uptake (Vo(2 max)) 64.7 +/- 2.6 ml x kg(-1) x min(-1)] performed two 11-day trials consuming either the Con or the HCHO diet. The last week of both trials consisted of IT. Performance was measured with a preloaded 8-km all-out run on the treadmill and 16-km all-out runs outdoors. Substrate utilization was measured using indirect calorimetry and continuous [U-(13)C]glucose infusion during 30 min of running at 58 and 77% Vo(2 max). Time to complete 8 km was negatively affected by the IT: time significantly increased by 61 +/- 23 and 155 +/- 38 s in the HCHO and Con trials, respectively. The 16-km times were significantly increased (by 8.2 +/- 2.1%) during the Con trial only. The Daily Analysis of Life Demands of Athletes questionnaire showed significant deterioration in mood states in both trials, whereas deterioration in global mood scores, as assessed with the Profile of Mood States, was more pronounced in the Con trial. Scores for fatigue were significantly higher in the Con compared with the HCHO trial. CHO oxidation decreased significantly from 1.7 +/- 0.2 to 1.2 +/- 0.2 g/min over the course of the Con trial, which was completely accounted for by a decrease in muscle glycogen oxidation. These findings indicate that an increase in dietary CHO content from 5.4 to 8.5 g CHO x kg(-1)x day(-1) (41 vs. 65% total energy intake, respectively) allowed better maintenance of physical performance and mood state over the course of training, thereby reducing the symptoms of overreaching.

Iron absorption from Spatone (a natural mineral water) for prevention of iron deficiency in pregnancy.

The absorption of iron from Spatone Iron-Plus has been investigated in pregnant women with iron deficiency anaemia. A total of 25 mg Fe was taken and absorption determined from the increase in serum iron concentration during a period of 3 h. Mean absorption was 28%, significantly higher than in nonpregnant, nonanaemic women (14%). These studies demonstrate that Spatone provides an alternative to the standard ferrous sulphate tablet for prevention of iron deficiency in pregnancy. As only lower doses of iron are required, the unpleasant side-effects of iron therapy are largely avoided.

Postoperative wound blistering: is there a link with dressing usage?

Practitioners on an orthopaedic ward used three different types of dressing on two groups of 100 patients who had undergone hip or knee operations, and compared the number of blisters that resulted. They describe their findings.

The reliability of cycling efficiency.

PURPOSE: The aim of this experiment was to establish the reproducibility of gross efficiency (GE), delta efficiency (DE), and economy (EC) during a graded cycle ergometer test in seventeen male subjects. METHODS: All subjects performed three identical exercise tests at a constant pedal cadence of 80 rpm on an electrically braked cycle ergometer. Energy expenditure was estimated from measures of oxygen uptake (VO(2)) and carbon dioxide production (VCO(2)) by using stoichiometric equations. RESULTS: The subjects characteristics were age 24 +/- 6 yr, body mass 74.6 +/- 6.9 kg, body fat 13.9 +/- 2.2%, and VO(2max) 61.9 +/- 2.4 mL x kg(-1) x min(-1) (all means +/- SD). Average GE, DE, and EC for the three tests were 19.8 +/- 0.6%, 25.8 +/- 1.5%, and 5.0 +/- 0.1 kJ x L(-1), respectively. The coefficients of variation (confidence limits) were GE 4.2 (3.2-6.4)%, DE 6.7 (5.0-10.0)%, and EC 3.3 (2.4-4.9)%. GE was significantly lower at 95 W and 130 W when compared with 165 W, 200 W, 235 W, 270 W, and 305 W. GE at 165 W was significantly lower (P < 0.05) that GE at 235 W. A weak correlation (r = 0.491; P < 0.05) was found between peak oxygen uptake (VO(2peak)) and GE, whereas no correlations were found between VO(2max) and DE or EC. CONCLUSION: We conclude that a graded exercise test with 3-min stages and 35-W increments is a method by which reproducible measurements of both GE and EC can be obtained, whereas measurements of DE seemed slightly more variable.

Smoking--do vascular surgeons practise what they preach?

Smoking is a major health problem in Great Britain and cigarette consumption is rising. Although there are studies concerning the smoking habits of hospital physicians, nurses and oral and maxillofacial surgeons, little is known about the smoking habits of vascular surgeons and the advice given by them to their patients. A questionnaire survey was conducted involving 422 members of the Vascular Surgical Society of Great Britain and Ireland. The response rate was 74%. The median age of responders was 51 years (range, 32-69 years) of whom 98% were men. Of responders, 98% routinely advise patients to stop smoking, 10% advise nicotine gum/patch, 39% provide antismoking information sheets, 11% are involved in an antismoking clinic/group and 74% check to see whether patients continue to smoke. The majority of responders would be prepared to offer revascularisation in patients who continue to smoke. Only 8 surgeons (3%) would not advise revascularisation in this group of patients. Only 10% of respondents were current smokers, 37% were ex-smokers and 53% had never smoked. Vascular surgeons, therefore, seem to practise what they preach.

Graphs: looking at relationships.

Research articles often incorporate data in the form of graphs. This article acts as a study guide to enable readers to understand and interpret the data produced in this way.

Developing nursing research in a contract-driven arena: inequities and iniquities.

Despite the need for nursing to become more evidence-based, there are a number of problems regarding developing nursing research.

Mortality from ruptured abdominal aortic aneurysm in Wales.

BACKGROUND: The aim of this study was to identify the incidence of, and mortality in, patients with a ruptured abdominal aortic aneurysm (AAA) reaching hospital alive in Wales. METHODS: Patients who presented with a ruptured AAA between September 1996 and August 1997 were analysed. Data were collected prospectively by an independent body, observing strict confidentiality. RESULTS: Some 233 patients with a confirmed ruptured AAA were identified, giving an incidence of eight per 100 000 total population. Some 133 patients (57 per cent) underwent attempted operative repair; 85 (64 per cent) of these died within 30 days. Of the 233 patients, 92 were admitted under the care of a vascular surgeon and 141 under a non-vascular surgeon. Vascular surgeons operated on 82 patients (89 per cent), of whom 50 (61 per cent) died, whereas non-vascular surgeons operated on 51 patients (36 per cent), of whom 35 (69 per cent) died. DISCUSSION: This study is unique as it is an independent prospective study of mortality in patients with a ruptured AAA who reached hospital alive. Mortality was independent of the operating surgeon, but vascular surgeons turned down significantly fewer patients than non-vascular surgeons (11 versus 64 per cent, P < 0.001).

Vascular surgical society of great britain and ireland: deaths from ruptured abdominal aortic aneurysm in wales

BACKGROUND: The aim was to determine the true incidence and operative mortality rate of patients with ruptured abdominal aortic aneurysm (AAA) who reach hospital alive in Wales. METHODS: Patients presenting with a ruptured AAA between September 1996 and August 1997 were analysed. The data were collected prospectively by an independent body, observing strict confidentiality. RESULTS: Two hundred and thirty-three patients with confirmed ruptured AAA were identified. One hundred and thirty-three patients (57 per cent) underwent attempted operative repair. Eighty-five (64 per cent) died within 30 days. All 100 patients who received no operation died. Of the 233 patients, 92 were admitted under vascular surgeons (VSs) and 141 under non-vascular surgeons (NVSs). VSs operated on 82 patients (89 per cent) of whom 50 (61 per cent) died; NVSs operated on 51 (36 per cent) of whom 35 (69 per cent) died. CONCLUSION: This study is the only independent prospective study of death among patients with ruptured AAA who reached hospital alive. Some 57 per cent of the patients with a ruptured AAA were operated on. The operative mortality rate was 64 per cent and the overall mortality rate was 79 per cent. VSs were significantly more aggressive (89 per cent) in the management of ruptured AAA (i.e. more likely to operate) than NVSs (36 per cent) (P < 0.0001). Despite this, the operative mortality rate for VSs was 61 per cent, whereas for NVSs it was 69 per cent (P = 0.372). The overall mortality rate (including operated and non-operated patients) for NVSs (89 per cent) was significantly higher than that for VSs (65 per cent) (P < 0.0001). In Conclusion:, ruptured AAA is common in Wales and associated with a high mortality rate even when managed by VSs.

Fine tuning the day surgery process.

This review suggests that nurses need to be more knowledgeable when it comes to the assessment of post-operative pain. The authors recommend the employment of a universal pre-operative assessment and discharge protocol, based on the patient's perspective.

Can feedback be individualised, useful, and economical?

An important, but often neglected, part of any research or audit exercise is the reporting back to participants of the results of that exercise. When feedback is made, it is often of a general, aggregated nature. Considerations of cost and psychological factors usually preclude feedback to individuals. As part of a larger study we have developed a prototype mechanism for providing such individual feedback. This was done by writing a computer program which automatically generated the report, using rules on how to interpret different patterns of responses to a questionnaire. Previous qualitative evaluation had shown a positive response from participating nurses. The current small-scale study reports a more formal evaluation. Participants who received reports on the degree to which their ward was practising primary nursing overwhelmingly found the reports readable, informative, encouraging, accurate and useful.

Bacteremia in young urban women admitted with pyelonephritis.

The objective of this study was to determine the rate of bacteremia in young women admitted to the hospital with presumed pyelonephritis and compare it with other published rates. The study design was a retrospective, structured chart review and a review of published reports of bacteremic pyelonephritis. An urban county teaching hospital provided the setting for the study. The patients were nonpregnant women (n = 98) 44 years of age or younger who were without bladder dysfunction and who had not been admitted to an intensive care unit. Further criteria for participation included discharge with the diagnosis of acute pyelonephritis. Blood cultures were ordered for 69 women; the results of 64 were noted in the chart. Twenty-three women (35.9% of those cultured; 23.4% of all patients) were diagnosed with bacteremia. In patients for whom blood culture results were obtained, trends developed between those patients with bacteremia and those with complicated pyelonephritis, defined as a known or newly discovered genitourinary abnormality or a risk factor (P = 0.044), those who were black (P = .044), those with higher pulses on admission (P = .050), those with more white blood cells per high-powered field after urinalysis (P = 0.007), and those whose fever lasted longer (P = 0.033). Blood culture results were positive in two patients whose urine cultures were negative. This comparatively high bacteremia rate supports routine ordering of blood cultures for urban women suspected of having pyelonephritis.

Applying lexical and semantic analysis to the exploration of free-text data.

A substantial study of primary nursing involving the authors ( 1 , 2 ) generated, in addition to the pre-coded data, a large number of free-text responses. We decided to investigate whether these less structured data could help to categorise and understand the leadership styles of ward sisters in the sample.

The incidence of injury in surfboat rowers.

A questionnaire was completed by 202 surfboat rowers. The questionnaire investigated injuries that occurred over the preceding two years. The injuries were classified according to the nature of onset of the injury, the anatomical location of the injury, and the age of the rower. Eighty percent of surfboat rowers reported some type of injury during the two years prior to completing the questionnaire. Eighty one percent of injuries were classified as chronic insidious onset injuries. The mean time lost from employment due to chronic insidious onset injuries was 10.4 days, Low back pain accounted for 60% of all injuries. Sixty percent of the acute injuries were hamstring or calf tears that were incurred during sprint running training. No relationship between age or surfboat rowing experience and incidence of injury was identified. The present study suggests that there is a high incidence of injury in surfboat rowing, and that most injuries are chronic injuries and are of an insidious onset.